* [PATCH v2 0/6] refactor the internals of record-full
@ 2026-04-23 15:25 Guinevere Larsen
2026-04-23 15:25 ` [PATCH v2 1/6] gdb/record: Refactor record history Guinevere Larsen
` (5 more replies)
0 siblings, 6 replies; 19+ messages in thread
From: Guinevere Larsen @ 2026-04-23 15:25 UTC (permalink / raw)
To: gdb-patches; +Cc: Guinevere Larsen
This series introduces a refactor and modernization to the record-full
history, moving it form a manually managed doubly-linked list into an
std::deque, which can make better use of caching and might make
execution faster.
The main driving force behind this change is the plan to implement
support for multithreaded inferiors, since each instruction will need to
know the thread that executed it, and it'll be much easier if there is a
more consistent spot to find all this information.
Guinevere Larsen (6):
gdb/record: Refactor record history
gdb/record: remove record_full_insn_num
gdb/record: c++ify internal structures of record-full.c
gdb/record: make record_full_history more c++-like
gdb/record: extract the PC to record_full_instruction
gdb/record: Define new version of the record-save section
gdb/NEWS | 4 +
gdb/aarch64-tdep.c | 2 -
gdb/amd64-linux-tdep.c | 3 -
gdb/arm-tdep.c | 2 -
gdb/i386-linux-tdep.c | 3 -
gdb/i386-tdep.c | 4 -
gdb/loongarch-tdep.c | 2 -
gdb/moxie-tdep.c | 2 -
gdb/ppc-linux-tdep.c | 3 -
gdb/record-full.c | 1668 +++++++++++++++++++---------------------
gdb/record-full.h | 1 -
gdb/riscv-tdep.c | 3 -
gdb/rs6000-tdep.c | 4 -
gdb/s390-linux-tdep.c | 3 -
gdb/s390-tdep.c | 2 -
15 files changed, 785 insertions(+), 921 deletions(-)
base-commit: 594acddca78d2ce96029c90cd2ef8d52c3ba1002
--
2.53.0
^ permalink raw reply [flat|nested] 19+ messages in thread
* [PATCH v2 1/6] gdb/record: Refactor record history
2026-04-23 15:25 [PATCH v2 0/6] refactor the internals of record-full Guinevere Larsen
@ 2026-04-23 15:25 ` Guinevere Larsen
2026-04-28 3:28 ` Thiago Jung Bauermann
2026-05-06 21:16 ` Schimpe, Christina
2026-04-23 15:26 ` [PATCH v2 2/6] gdb/record: remove record_full_insn_num Guinevere Larsen
` (4 subsequent siblings)
5 siblings, 2 replies; 19+ messages in thread
From: Guinevere Larsen @ 2026-04-23 15:25 UTC (permalink / raw)
To: gdb-patches; +Cc: Guinevere Larsen
This is the first step in a large refactor in how GDB keeps execution
history. Rather than using a linked list where multiple entries can
describe a single instruction, the history will now be stored in an
std::deque, each instruction being one entry in the deque.
The choice was initially to use an std::vector, but it would become
unwieldy because it needs all the memory to be consecutive, which is
hard for 200 thousand entries. Deque was picked because it was a nice
midpoint between vector (maximum cache cohesion) and linked list
(maximum ease of finding space to store more).
Each instruction in memory will be now one record_full_instruction
entry, which for this commit just contains a vector of
record_full_entry for the effects of the instruction, and the data that
was stored in the record_full_end entry (that is, the instruction number
and the signal, if any).
This change introduced a minimal performance improvement (what's
important is that it isn't a degradation) and a reduction in the total
memory footprint of roughly 20% if the entire history is used.
---
gdb/aarch64-tdep.c | 2 -
gdb/amd64-linux-tdep.c | 3 -
gdb/arm-tdep.c | 2 -
gdb/i386-linux-tdep.c | 3 -
gdb/i386-tdep.c | 4 -
gdb/loongarch-tdep.c | 2 -
gdb/moxie-tdep.c | 2 -
gdb/ppc-linux-tdep.c | 3 -
gdb/record-full.c | 1180 ++++++++++++++++------------------------
gdb/record-full.h | 1 -
gdb/riscv-tdep.c | 3 -
gdb/rs6000-tdep.c | 4 -
gdb/s390-linux-tdep.c | 3 -
gdb/s390-tdep.c | 2 -
14 files changed, 476 insertions(+), 738 deletions(-)
diff --git a/gdb/aarch64-tdep.c b/gdb/aarch64-tdep.c
index 4befaa2720d..a532992b1d8 100644
--- a/gdb/aarch64-tdep.c
+++ b/gdb/aarch64-tdep.c
@@ -6210,8 +6210,6 @@ aarch64_process_record (struct gdbarch *gdbarch, struct regcache *regcache,
aarch64_record.aarch64_mems[rec_no].len))
ret = -1;
- if (record_full_arch_list_add_end ())
- ret = -1;
}
deallocate_reg_mem (&aarch64_record);
diff --git a/gdb/amd64-linux-tdep.c b/gdb/amd64-linux-tdep.c
index a5ac26654cf..9b23db72bbe 100644
--- a/gdb/amd64-linux-tdep.c
+++ b/gdb/amd64-linux-tdep.c
@@ -1591,9 +1591,6 @@ amd64_linux_record_signal (struct gdbarch *gdbarch,
+ AMD64_LINUX_frame_size))
return -1;
- if (record_full_arch_list_add_end ())
- return -1;
-
return 0;
}
diff --git a/gdb/arm-tdep.c b/gdb/arm-tdep.c
index 08cce9dbad8..1ce0927f26b 100644
--- a/gdb/arm-tdep.c
+++ b/gdb/arm-tdep.c
@@ -14911,8 +14911,6 @@ arm_process_record (struct gdbarch *gdbarch, struct regcache *regcache,
}
}
- if (record_full_arch_list_add_end ())
- ret = -1;
}
diff --git a/gdb/i386-linux-tdep.c b/gdb/i386-linux-tdep.c
index 23aeccac9fc..4f33766fcdd 100644
--- a/gdb/i386-linux-tdep.c
+++ b/gdb/i386-linux-tdep.c
@@ -949,9 +949,6 @@ i386_linux_record_signal (struct gdbarch *gdbarch,
I386_LINUX_xstate + I386_LINUX_frame_size))
return -1;
- if (record_full_arch_list_add_end ())
- return -1;
-
return 0;
}
\f
diff --git a/gdb/i386-tdep.c b/gdb/i386-tdep.c
index fa935b5fcdb..fee36b46a73 100644
--- a/gdb/i386-tdep.c
+++ b/gdb/i386-tdep.c
@@ -5201,8 +5201,6 @@ i386_record_vex (struct i386_record_s *ir, uint8_t vex_w, uint8_t vex_r,
}
record_full_arch_list_add_reg (ir->regcache, ir->regmap[X86_RECORD_REIP_REGNUM]);
- if (record_full_arch_list_add_end ())
- return -1;
return 0;
}
@@ -8359,8 +8357,6 @@ Do you want to stop the program?"),
/* In the future, maybe still need to deal with need_dasm. */
I386_RECORD_FULL_ARCH_LIST_ADD_REG (X86_RECORD_REIP_REGNUM);
- if (record_full_arch_list_add_end ())
- return -1;
return 0;
diff --git a/gdb/loongarch-tdep.c b/gdb/loongarch-tdep.c
index 225b1abb703..5ec6b2a48d0 100644
--- a/gdb/loongarch-tdep.c
+++ b/gdb/loongarch-tdep.c
@@ -2789,8 +2789,6 @@ loongarch_process_record (struct gdbarch *gdbarch, struct regcache *regcache,
LOONGARCH_PC_REGNUM))
return -1;
- if (record_full_arch_list_add_end ())
- return -1;
}
return ret;
diff --git a/gdb/moxie-tdep.c b/gdb/moxie-tdep.c
index c8a04d21f59..2f8f0186488 100644
--- a/gdb/moxie-tdep.c
+++ b/gdb/moxie-tdep.c
@@ -1040,8 +1040,6 @@ moxie_process_record (struct gdbarch *gdbarch, struct regcache *regcache,
if (record_full_arch_list_add_reg (regcache, MOXIE_PC_REGNUM))
return -1;
- if (record_full_arch_list_add_end ())
- return -1;
return 0;
}
diff --git a/gdb/ppc-linux-tdep.c b/gdb/ppc-linux-tdep.c
index 19698eaacbe..e2f53551709 100644
--- a/gdb/ppc-linux-tdep.c
+++ b/gdb/ppc-linux-tdep.c
@@ -1565,9 +1565,6 @@ ppc_linux_record_signal (struct gdbarch *gdbarch, struct regcache *regcache,
if (record_full_arch_list_add_mem (sp, SIGNAL_FRAMESIZE + sizeof_rt_sigframe))
return -1;
- if (record_full_arch_list_add_end ())
- return -1;
-
return 0;
}
diff --git a/gdb/record-full.c b/gdb/record-full.c
index 69d2c100e57..aac69cee17e 100644
--- a/gdb/record-full.c
+++ b/gdb/record-full.c
@@ -72,20 +72,17 @@
#define DEFAULT_RECORD_FULL_INSN_MAX_NUM 200000
#define RECORD_FULL_IS_REPLAY \
- (record_full_list->next || ::execution_direction == EXEC_REVERSE)
+ ( (record_full_next_insn != record_full_list.size ()) \
+ || ::execution_direction == EXEC_REVERSE)
#define RECORD_FULL_FILE_MAGIC netorder32(0x20091016)
/* These are the core structs of the process record functionality.
A record_full_entry is a record of the value change of a register
- ("record_full_reg") or a part of memory ("record_full_mem"). And each
- instruction must have a struct record_full_entry ("record_full_end")
- that indicates that this is the last struct record_full_entry of this
- instruction.
-
- Each struct record_full_entry is linked to "record_full_list" by "prev"
- and "next" pointers. */
+ ("record_full_reg") or a part of memory ("record_full_mem").
+ These are saved on the record_full_instruction struct, which also
+ contains some extra information, such as delivered signals. */
struct record_full_mem_entry
{
@@ -112,47 +109,14 @@ struct record_full_reg_entry
} u;
};
-struct record_full_end_entry
-{
- enum gdb_signal sigval;
- ULONGEST insn_num;
-};
-
enum record_full_type
{
- record_full_end = 0,
record_full_reg,
record_full_mem
};
-/* This is the data structure that makes up the execution log.
-
- The execution log consists of a single linked list of entries
- of type "struct record_full_entry". It is doubly linked so that it
- can be traversed in either direction.
-
- The start of the list is anchored by a struct called
- "record_full_first". The pointer "record_full_list" either points
- to the last entry that was added to the list (in record mode), or to
- the next entry in the list that will be executed (in replay mode).
-
- Each list element (struct record_full_entry), in addition to next
- and prev pointers, consists of a union of three entry types: mem,
- reg, and end. A field called "type" determines which entry type is
- represented by a given list element.
-
- Each instruction that is added to the execution log is represented
- by a variable number of list elements ('entries'). The instruction
- will have one "reg" entry for each register that is changed by
- executing the instruction (including the PC in every case). It
- will also have one "mem" entry for each memory change. Finally,
- each instruction will have an "end" entry that separates it from
- the changes associated with the next instruction. */
-
struct record_full_entry
{
- struct record_full_entry *prev;
- struct record_full_entry *next;
enum record_full_type type;
union
{
@@ -160,11 +124,31 @@ struct record_full_entry
struct record_full_reg_entry reg;
/* mem */
struct record_full_mem_entry mem;
- /* end */
- struct record_full_end_entry end;
} u;
};
+/* This is the main structure that comprises the execution log.
+ Each instruction is comprised of:
+ * The instruction number: How many instructions were recorded before
+ this one;
+ * sigval: Whether the inferior received a signal while the following
+ instruction was being recorded;
+ * effects: A list of record_full_entry structures, each of which
+ describing one effect that the instruction has on the inferior.
+
+ Note, the signal is stored in the previous instruction for historical
+ reasons. This is how it was first implemented, and no one has gotten
+ around to changing it yet. */
+
+struct record_full_instruction
+{
+ /* This might be different from the index if
+ we had to remove the first few instructions. */
+ uint32_t insn_num;
+ std::optional<gdb_signal> sigval;
+ std::vector<record_full_entry> effects;
+};
+
/* If true, query if PREC cannot record memory
change of next instruction. */
bool record_full_memory_query = false;
@@ -181,27 +165,25 @@ static detached_regcache *record_full_core_regbuf = NULL;
static std::vector<target_section> record_full_core_sections;
static struct record_full_core_buf_entry *record_full_core_buf_list = NULL;
-/* The following variables are used for managing the linked list that
- represents the execution log.
+/* The following variables are used for managing the history of executed
+ instructions from the inferior.
- record_full_first is the anchor that holds down the beginning of
- the list.
+ record_full_list contains all instructions that were fully executed and
+ saved to the log, so that we can replay the execution.
- record_full_list serves two functions:
- 1) In record mode, it anchors the end of the list.
- 2) In replay mode, it traverses the list and points to
- the next instruction that must be emulated.
+ record_full_next_insn always points to the next instruction that would
+ be executed if the inferior executes forward. In the special case when
+ the inferior is not replaying, record_full_next_insn points past the
+ end of the history.
- record_full_arch_list_head and record_full_arch_list_tail are used
- to manage a separate list, which is used to build up the change
- elements of the currently executing instruction during record mode.
- When this instruction has been completely annotated in the "arch
- list", it will be appended to the main execution log. */
+ record_full_incomplete_instruction holds a partial instruction, while
+ the lower target is disassembling the instruction, or as partial xfers are
+ happening. It is manipulated by the "arch list" functions for historical
+ reasons. */
-static struct record_full_entry record_full_first;
-static struct record_full_entry *record_full_list = &record_full_first;
-static struct record_full_entry *record_full_arch_list_head = NULL;
-static struct record_full_entry *record_full_arch_list_tail = NULL;
+static std::deque<record_full_instruction> record_full_list;
+static record_full_instruction record_full_incomplete_instruction;
+int record_full_next_insn;
/* true ask user. false auto delete the last struct record_full_entry. */
static bool record_full_stop_at_limit = true;
@@ -361,6 +343,14 @@ record_full_target::kill ()
record_kill (this);
}
+static void
+record_full_reset_incomplete ()
+{
+ record_full_incomplete_instruction.effects.clear ();
+ record_full_incomplete_instruction.sigval.reset ();
+ record_full_incomplete_instruction.insn_num = 0;
+}
+
/* See record-full.h. */
int
@@ -390,156 +380,120 @@ static struct cmd_list_element *show_record_full_cmdlist;
/* Command list for "record full". */
static struct cmd_list_element *record_full_cmdlist;
-static void record_full_goto_insn (struct record_full_entry *entry,
+static void record_full_goto_insn (size_t target_insn,
enum exec_direction_kind dir);
-/* Alloc and free functions for record_full_reg, record_full_mem, and
- record_full_end entries. */
+/* Initialization and cleanup functions for record_full_reg and
+ record_full_mem entries. */
-/* Alloc a record_full_reg record entry. */
+/* Init a record_full_reg record entry. */
-static inline struct record_full_entry *
-record_full_reg_alloc (struct regcache *regcache, int regnum)
+static inline struct record_full_entry
+record_full_reg_init (struct regcache *regcache, int regnum)
{
- struct record_full_entry *rec;
+ struct record_full_entry rec;
struct gdbarch *gdbarch = regcache->arch ();
- rec = XCNEW (struct record_full_entry);
- rec->type = record_full_reg;
- rec->u.reg.num = regnum;
- rec->u.reg.len = register_size (gdbarch, regnum);
- if (rec->u.reg.len > sizeof (rec->u.reg.u.buf))
- rec->u.reg.u.ptr = (gdb_byte *) xmalloc (rec->u.reg.len);
+ rec.type = record_full_reg;
+ rec.u.reg.num = regnum;
+ rec.u.reg.len = register_size (gdbarch, regnum);
+ if (rec.u.reg.len > sizeof (rec.u.reg.u.buf))
+ rec.u.reg.u.ptr = (gdb_byte *) xmalloc (rec.u.reg.len);
return rec;
}
-/* Free a record_full_reg record entry. */
+/* Cleanup a record_full_reg record entry. */
static inline void
-record_full_reg_release (struct record_full_entry *rec)
+record_full_reg_cleanup (struct record_full_entry rec)
{
- gdb_assert (rec->type == record_full_reg);
- if (rec->u.reg.len > sizeof (rec->u.reg.u.buf))
- xfree (rec->u.reg.u.ptr);
- xfree (rec);
+ gdb_assert (rec.type == record_full_reg);
+ if (rec.u.reg.len > sizeof (rec.u.reg.u.buf))
+ xfree (rec.u.reg.u.ptr);
}
-/* Alloc a record_full_mem record entry. */
+/* Init a record_full_mem record entry. */
-static inline struct record_full_entry *
-record_full_mem_alloc (CORE_ADDR addr, int len)
+static inline struct record_full_entry
+record_full_mem_init (CORE_ADDR addr, int len)
{
- struct record_full_entry *rec;
+ struct record_full_entry rec;
- rec = XCNEW (struct record_full_entry);
- rec->type = record_full_mem;
- rec->u.mem.addr = addr;
- rec->u.mem.len = len;
- if (rec->u.mem.len > sizeof (rec->u.mem.u.buf))
- rec->u.mem.u.ptr = (gdb_byte *) xmalloc (len);
+ rec.type = record_full_mem;
+ rec.u.mem.addr = addr;
+ rec.u.mem.len = len;
+ if (rec.u.mem.len > sizeof (rec.u.mem.u.buf))
+ rec.u.mem.u.ptr = (gdb_byte *) xmalloc (len);
+ rec.u.mem.mem_entry_not_accessible = 0;
return rec;
}
-/* Free a record_full_mem record entry. */
+/* Cleanup a record_full_mem record entry. */
static inline void
-record_full_mem_release (struct record_full_entry *rec)
-{
- gdb_assert (rec->type == record_full_mem);
- if (rec->u.mem.len > sizeof (rec->u.mem.u.buf))
- xfree (rec->u.mem.u.ptr);
- xfree (rec);
-}
-
-/* Alloc a record_full_end record entry. */
-
-static inline struct record_full_entry *
-record_full_end_alloc (void)
+record_full_mem_cleanup (struct record_full_entry rec)
{
- struct record_full_entry *rec;
-
- rec = XCNEW (struct record_full_entry);
- rec->type = record_full_end;
-
- return rec;
+ gdb_assert (rec.type == record_full_mem);
+ if (rec.u.mem.len > sizeof (rec.u.mem.u.buf))
+ xfree (rec.u.mem.u.ptr);
}
-/* Free a record_full_end record entry. */
+/* Free one record entry, any type. */
static inline void
-record_full_end_release (struct record_full_entry *rec)
-{
- xfree (rec);
-}
-
-/* Free one record entry, any type.
- Return entry->type, in case caller wants to know. */
-
-static inline enum record_full_type
-record_full_entry_release (struct record_full_entry *rec)
+record_full_entry_cleanup (struct record_full_entry rec)
{
- enum record_full_type type = rec->type;
- switch (type) {
+ switch (rec.type) {
case record_full_reg:
- record_full_reg_release (rec);
+ record_full_reg_cleanup (rec);
break;
case record_full_mem:
- record_full_mem_release (rec);
- break;
- case record_full_end:
- record_full_end_release (rec);
+ record_full_mem_cleanup (rec);
break;
}
- return type;
}
-/* Free all record entries in list pointed to by REC. */
-
static void
-record_full_list_release (struct record_full_entry *rec)
+record_full_reset_history ()
{
- if (!rec)
- return;
-
- while (rec->next)
- rec = rec->next;
+ record_full_insn_num = 0;
+ record_full_insn_count = 0;
+ record_full_next_insn = 0;
- while (rec->prev)
+ for (auto &insn : record_full_list)
{
- rec = rec->prev;
- record_full_entry_release (rec->next);
+ for (auto &entry : insn.effects)
+ record_full_entry_cleanup (entry);
}
- if (rec == &record_full_first)
- {
- record_full_insn_num = 0;
- record_full_first.next = NULL;
- }
- else
- record_full_entry_release (rec);
+ record_full_list.clear ();
}
-/* Free all record entries forward of the given list position. */
-
static void
-record_full_list_release_following (struct record_full_entry *rec)
+record_full_list_release_following (int index)
{
- struct record_full_entry *tmp = rec->next;
-
- rec->next = NULL;
- while (tmp)
+ for (int i = record_full_list.size () - 1; i > index; i--)
{
- rec = tmp->next;
- if (record_full_entry_release (tmp) == record_full_end)
- {
- record_full_insn_num--;
- record_full_insn_count--;
- }
- tmp = rec;
+ for (auto &entry : record_full_list[i].effects)
+ record_full_entry_cleanup (entry);
+ record_full_list.pop_back ();
}
+ /* Set the next instruction to be past the end of the log so we
+ start recording if the user moves forward again. */
+ record_full_next_insn = index;
+}
+
+static void
+record_full_save_instruction ()
+{
+ ++record_full_insn_count;
+ record_full_incomplete_instruction.insn_num = record_full_insn_count;
+ record_full_incomplete_instruction.effects.shrink_to_fit ();
+ record_full_list.push_back (record_full_incomplete_instruction);
+ record_full_next_insn++;
}
/* Delete the first instruction from the beginning of the log, to make
@@ -550,52 +504,22 @@ record_full_list_release_following (struct record_full_entry *rec)
static void
record_full_list_release_first (void)
{
- struct record_full_entry *tmp;
-
- if (!record_full_first.next)
+ if (record_full_list.empty ())
return;
- /* Loop until a record_full_end. */
- while (1)
- {
- /* Cut record_full_first.next out of the linked list. */
- tmp = record_full_first.next;
- record_full_first.next = tmp->next;
- tmp->next->prev = &record_full_first;
-
- /* tmp is now isolated, and can be deleted. */
- if (record_full_entry_release (tmp) == record_full_end)
- break; /* End loop at first record_full_end. */
+ for (auto &entry : record_full_list[0].effects)
+ record_full_entry_cleanup (entry);
- if (!record_full_first.next)
- {
- gdb_assert (record_full_insn_num == 1);
- break; /* End loop when list is empty. */
- }
- }
+ record_full_list.pop_front ();
+ --record_full_next_insn;
}
/* Add a struct record_full_entry to record_full_arch_list. */
static void
-record_full_arch_list_add (struct record_full_entry *rec)
+record_full_arch_list_add (struct record_full_entry &rec)
{
- if (record_debug > 1)
- gdb_printf (gdb_stdlog,
- "Process record: record_full_arch_list_add %s.\n",
- host_address_to_string (rec));
-
- if (record_full_arch_list_tail)
- {
- record_full_arch_list_tail->next = rec;
- rec->prev = record_full_arch_list_tail;
- record_full_arch_list_tail = rec;
- }
- else
- {
- record_full_arch_list_head = rec;
- record_full_arch_list_tail = rec;
- }
+ record_full_incomplete_instruction.effects.push_back (rec);
}
/* Return the value storage location of a record entry. */
@@ -613,7 +537,6 @@ record_full_get_loc (struct record_full_entry *rec)
return rec->u.reg.u.ptr;
else
return rec->u.reg.u.buf;
- case record_full_end:
default:
gdb_assert_not_reached ("unexpected record_full_entry type");
return NULL;
@@ -625,7 +548,7 @@ record_full_get_loc (struct record_full_entry *rec)
int
record_full_arch_list_add_reg (struct regcache *regcache, int regnum)
{
- struct record_full_entry *rec;
+ struct record_full_entry rec;
if (record_debug > 1)
gdb_printf (gdb_stdlog,
@@ -633,9 +556,9 @@ record_full_arch_list_add_reg (struct regcache *regcache, int regnum)
"record list.\n",
regnum);
- rec = record_full_reg_alloc (regcache, regnum);
+ rec = record_full_reg_init (regcache, regnum);
- regcache->cooked_read (regnum, record_full_get_loc (rec));
+ regcache->cooked_read (regnum, record_full_get_loc (&rec));
record_full_arch_list_add (rec);
@@ -648,7 +571,7 @@ record_full_arch_list_add_reg (struct regcache *regcache, int regnum)
int
record_full_arch_list_add_mem (CORE_ADDR addr, int len)
{
- struct record_full_entry *rec;
+ struct record_full_entry rec;
if (record_debug > 1)
gdb_printf (gdb_stdlog,
@@ -659,12 +582,12 @@ record_full_arch_list_add_mem (CORE_ADDR addr, int len)
if (!addr) /* FIXME: Why? Some arch must permit it... */
return 0;
- rec = record_full_mem_alloc (addr, len);
+ rec = record_full_mem_init (addr, len);
if (record_read_memory (current_inferior ()->arch (), addr,
- record_full_get_loc (rec), len))
+ record_full_get_loc (&rec), len))
{
- record_full_mem_release (rec);
+ record_full_mem_cleanup (rec);
return -1;
}
@@ -673,27 +596,6 @@ record_full_arch_list_add_mem (CORE_ADDR addr, int len)
return 0;
}
-/* Add a record_full_end type struct record_full_entry to
- record_full_arch_list. */
-
-int
-record_full_arch_list_add_end (void)
-{
- struct record_full_entry *rec;
-
- if (record_debug > 1)
- gdb_printf (gdb_stdlog,
- "Process record: add end to arch list.\n");
-
- rec = record_full_end_alloc ();
- rec->u.end.sigval = GDB_SIGNAL_0;
- rec->u.end.insn_num = ++record_full_insn_count;
-
- record_full_arch_list_add (rec);
-
- return 0;
-}
-
static void
record_full_check_insn_num (void)
{
@@ -725,8 +627,7 @@ record_full_message (struct regcache *regcache, enum gdb_signal signal)
try
{
- record_full_arch_list_head = NULL;
- record_full_arch_list_tail = NULL;
+ record_full_reset_incomplete ();
/* Check record_full_insn_num. */
record_full_check_insn_num ();
@@ -746,20 +647,16 @@ record_full_message (struct regcache *regcache, enum gdb_signal signal)
the user says something different, like "deliver this signal"
during the replay mode).
- User should understand that nothing he does during the replay
- mode will change the behavior of the child. If he tries,
+ User should understand that nothing they do during the replay
+ mode will change the behavior of the child. If they try,
then that is a user error.
But we should still deliver the signal to gdb during the replay,
if we delivered it during the recording. Therefore we should
record the signal during record_full_wait, not
record_full_resume. */
- if (record_full_list != &record_full_first) /* FIXME better way
- to check */
- {
- gdb_assert (record_full_list->type == record_full_end);
- record_full_list->u.end.sigval = signal;
- }
+ if (signal != GDB_SIGNAL_0)
+ record_full_list[record_full_next_insn - 1].sigval = signal;
if (signal == GDB_SIGNAL_0
|| !gdbarch_process_record_signal_p (gdbarch))
@@ -778,13 +675,11 @@ record_full_message (struct regcache *regcache, enum gdb_signal signal)
}
catch (const gdb_exception &ex)
{
- record_full_list_release (record_full_arch_list_tail);
+ record_full_reset_incomplete ();
throw;
}
- record_full_list->next = record_full_arch_list_head;
- record_full_arch_list_head->prev = record_full_list;
- record_full_list = record_full_arch_list_tail;
+ record_full_save_instruction ();
if (record_full_insn_num == record_full_insn_max_num)
record_full_list_release_first ();
@@ -829,9 +724,9 @@ static enum target_stop_reason record_full_stop_reason
entries and memory entries, followed by an 'end' entry. */
static inline void
-record_full_exec_insn (struct regcache *regcache,
- struct gdbarch *gdbarch,
- struct record_full_entry *entry)
+record_full_exec_entry (struct regcache *regcache,
+ struct gdbarch *gdbarch,
+ struct record_full_entry *entry)
{
switch (entry->type)
{
@@ -909,6 +804,15 @@ record_full_exec_insn (struct regcache *regcache,
}
}
+static inline void
+record_full_exec_insn (struct regcache *regcache,
+ struct gdbarch *gdbarch,
+ record_full_instruction &insn)
+{
+ for (auto &entry : insn.effects)
+ record_full_exec_entry (regcache, gdbarch, &entry);
+}
+
static void record_full_restore (struct bfd &cbfd);
/* Asynchronous signal handle registered as event loop source for when
@@ -983,10 +887,7 @@ record_full_open (const char *args, int from_tty)
record_preopen ();
/* Reset */
- record_full_insn_num = 0;
- record_full_insn_count = 0;
- record_full_list = &record_full_first;
- record_full_list->next = NULL;
+ record_full_reset_history ();
bfd *cbfd = get_inferior_core_bfd (current_inferior ());
if (cbfd != nullptr)
@@ -1014,7 +915,7 @@ record_full_base_target::close ()
if (record_debug)
gdb_printf (gdb_stdlog, "Process record: record_full_close\n");
- record_full_list_release (record_full_list);
+ record_full_reset_history ();
/* Release record_full_core_regbuf. */
if (record_full_core_regbuf)
@@ -1313,7 +1214,6 @@ record_full_wait_1 (struct target_ops *ops,
struct gdbarch *gdbarch = regcache->arch ();
const address_space *aspace = current_inferior ()->aspace.get ();
int continue_flag = 1;
- int first_record_full_end = 1;
try
{
@@ -1322,7 +1222,6 @@ record_full_wait_1 (struct target_ops *ops,
record_full_stop_reason = TARGET_STOPPED_BY_NO_REASON;
status->set_stopped (GDB_SIGNAL_0);
- /* Check breakpoint when forward execute. */
if (execution_direction == EXEC_FORWARD)
{
tmp_pc = regcache_read_pc (regcache);
@@ -1330,8 +1229,7 @@ record_full_wait_1 (struct target_ops *ops,
&record_full_stop_reason))
{
if (record_debug)
- gdb_printf (gdb_stdlog,
- "Process record: break at %s.\n",
+ gdb_printf (gdb_stdlog, "Process record: break at %s.\n",
paddress (gdbarch, tmp_pc));
goto replay_out;
}
@@ -1344,10 +1242,10 @@ record_full_wait_1 (struct target_ops *ops,
the signal. */
target_terminal::ours ();
- /* In EXEC_FORWARD mode, record_full_list points to the tail of prev
- instruction. */
- if (execution_direction == EXEC_FORWARD && record_full_list->next)
- record_full_list = record_full_list->next;
+ /* In EXEC_FORWARD mode, record_full_next_insn is the next
+ instruction to be executed. */
+ if (execution_direction == EXEC_REVERSE)
+ record_full_next_insn--;
/* Loop over the record_full_list, looking for the next place to
stop. */
@@ -1355,108 +1253,92 @@ record_full_wait_1 (struct target_ops *ops,
{
/* Check for beginning and end of log. */
if (execution_direction == EXEC_REVERSE
- && record_full_list == &record_full_first)
+ && record_full_next_insn < 0)
{
/* Hit beginning of record log in reverse. */
status->set_no_history ();
+ record_full_next_insn = 0;
break;
}
if (execution_direction != EXEC_REVERSE
- && !record_full_list->next)
+ && record_full_next_insn == record_full_list.size ())
{
/* Hit end of record log going forward. */
status->set_no_history ();
break;
}
- record_full_exec_insn (regcache, gdbarch, record_full_list);
+ record_full_exec_insn
+ (regcache, gdbarch,
+ record_full_list[record_full_next_insn]);
- if (record_full_list->type == record_full_end)
+ /* step */
+ if (record_full_resume_step)
{
if (record_debug > 1)
- gdb_printf
- (gdb_stdlog,
- "Process record: record_full_end %s to "
- "inferior.\n",
- host_address_to_string (record_full_list));
-
- if (first_record_full_end
- && execution_direction == EXEC_REVERSE)
- {
- /* When reverse execute, the first
- record_full_end is the part of current
- instruction. */
- first_record_full_end = 0;
- }
- else
- {
- /* In EXEC_REVERSE mode, this is the
- record_full_end of prev instruction. In
- EXEC_FORWARD mode, this is the
- record_full_end of current instruction. */
- /* step */
- if (record_full_resume_step)
- {
- if (record_debug > 1)
- gdb_printf (gdb_stdlog,
- "Process record: step.\n");
- continue_flag = 0;
- }
-
- /* check breakpoint */
- tmp_pc = regcache_read_pc (regcache);
- if (record_check_stopped_by_breakpoint
- (aspace, tmp_pc, &record_full_stop_reason))
- {
- if (record_debug)
- gdb_printf (gdb_stdlog,
- "Process record: break "
- "at %s.\n",
- paddress (gdbarch, tmp_pc));
+ gdb_printf (gdb_stdlog,
+ "Process record: step.\n");
+ continue_flag = 0;
+ }
- continue_flag = 0;
- }
+ /* check breakpoint */
+ tmp_pc = regcache_read_pc (regcache);
+ if (record_check_stopped_by_breakpoint
+ (aspace, tmp_pc, &record_full_stop_reason))
+ {
+ if (record_debug)
+ gdb_printf (gdb_stdlog,
+ "Process record: break "
+ "at %s.\n",
+ paddress (gdbarch, tmp_pc));
- if (record_full_stop_reason
- == TARGET_STOPPED_BY_WATCHPOINT)
- {
- if (record_debug)
- gdb_printf (gdb_stdlog,
- "Process record: hit hw "
- "watchpoint.\n");
- continue_flag = 0;
- }
- /* Check target signal */
- if (record_full_list->u.end.sigval != GDB_SIGNAL_0)
- /* FIXME: better way to check */
- continue_flag = 0;
- }
+ continue_flag = 0;
}
- if (continue_flag)
+ if (record_full_stop_reason
+ == TARGET_STOPPED_BY_WATCHPOINT)
{
- if (execution_direction == EXEC_REVERSE)
- {
- if (record_full_list->prev)
- record_full_list = record_full_list->prev;
- }
- else
- {
- if (record_full_list->next)
- record_full_list = record_full_list->next;
- }
+ if (record_debug)
+ gdb_printf (gdb_stdlog,
+ "Process record: hit hw "
+ "watchpoint.\n");
+ continue_flag = 0;
}
+ if (record_full_list[record_full_next_insn].sigval.has_value ())
+ continue_flag = 0;
+
+ if (execution_direction == EXEC_REVERSE)
+ record_full_next_insn--;
+ else
+ record_full_next_insn++;
}
while (continue_flag);
+ if (record_full_next_insn < 0)
+ {
+ gdb_assert (execution_direction == EXEC_REVERSE);
+ record_full_next_insn = 0;
+ }
+ else if (record_full_next_insn > record_full_list.size ())
+ {
+ gdb_assert (execution_direction == EXEC_FORWARD);
+ record_full_next_insn = record_full_list.size ();
+ }
+ /* Reset the current instruciton to point to the one to be replayed
+ moving forward. */
+ else if (execution_direction == EXEC_REVERSE)
+ record_full_next_insn++;
+
replay_out:
if (status->kind () == TARGET_WAITKIND_STOPPED)
{
+ int insn = (execution_direction == EXEC_FORWARD)
+ ? record_full_next_insn - 1 : record_full_next_insn;
if (record_full_get_sig)
status->set_stopped (GDB_SIGNAL_INT);
- else if (record_full_list->u.end.sigval != GDB_SIGNAL_0)
- /* FIXME: better way to check */
- status->set_stopped (record_full_list->u.end.sigval);
+ else if (record_full_list[insn].sigval.has_value ())
+ status->set_stopped
+ (record_full_list[insn].sigval.value ());
else
status->set_stopped (GDB_SIGNAL_TRAP);
}
@@ -1464,12 +1346,9 @@ record_full_wait_1 (struct target_ops *ops,
catch (const gdb_exception &ex)
{
if (execution_direction == EXEC_REVERSE)
- {
- if (record_full_list->next)
- record_full_list = record_full_list->next;
- }
+ record_full_next_insn++;
else
- record_full_list = record_full_list->prev;
+ record_full_next_insn--;
throw;
}
@@ -1557,8 +1436,7 @@ record_full_registers_change (struct regcache *regcache, int regnum)
/* Check record_full_insn_num. */
record_full_check_insn_num ();
- record_full_arch_list_head = NULL;
- record_full_arch_list_tail = NULL;
+ record_full_reset_incomplete ();
if (regnum < 0)
{
@@ -1568,7 +1446,7 @@ record_full_registers_change (struct regcache *regcache, int regnum)
{
if (record_full_arch_list_add_reg (regcache, i))
{
- record_full_list_release (record_full_arch_list_tail);
+ record_full_reset_incomplete ();
error (_("Process record: failed to record execution log."));
}
}
@@ -1577,18 +1455,11 @@ record_full_registers_change (struct regcache *regcache, int regnum)
{
if (record_full_arch_list_add_reg (regcache, regnum))
{
- record_full_list_release (record_full_arch_list_tail);
+ record_full_reset_incomplete ();
error (_("Process record: failed to record execution log."));
}
}
- if (record_full_arch_list_add_end ())
- {
- record_full_list_release (record_full_arch_list_tail);
- error (_("Process record: failed to record execution log."));
- }
- record_full_list->next = record_full_arch_list_head;
- record_full_arch_list_head->prev = record_full_list;
- record_full_list = record_full_arch_list_tail;
+ record_full_save_instruction ();
if (record_full_insn_num == record_full_insn_max_num)
record_full_list_release_first ();
@@ -1607,7 +1478,7 @@ record_full_target::store_registers (struct regcache *regcache, int regno)
{
int n;
- /* Let user choose if he wants to write register or not. */
+ /* Let user choose if they want to write register or not. */
if (regno < 0)
n =
query (_("Because GDB is in replay mode, changing the "
@@ -1642,7 +1513,7 @@ record_full_target::store_registers (struct regcache *regcache, int regno)
}
/* Destroy the record from here forward. */
- record_full_list_release_following (record_full_list);
+ record_full_list_release_following (record_full_next_insn);
}
record_full_registers_change (regcache, regno);
@@ -1675,36 +1546,24 @@ record_full_target::xfer_partial (enum target_object object,
error (_("Process record canceled the operation."));
/* Destroy the record from here forward. */
- record_full_list_release_following (record_full_list);
+ record_full_list_release_following (record_full_next_insn);
}
/* Check record_full_insn_num */
record_full_check_insn_num ();
/* Record registers change to list as an instruction. */
- record_full_arch_list_head = NULL;
- record_full_arch_list_tail = NULL;
+ record_full_reset_incomplete ();
if (record_full_arch_list_add_mem (offset, len))
{
- record_full_list_release (record_full_arch_list_tail);
+ record_full_reset_incomplete ();
if (record_debug)
gdb_printf (gdb_stdlog,
"Process record: failed to record "
"execution log.");
return TARGET_XFER_E_IO;
}
- if (record_full_arch_list_add_end ())
- {
- record_full_list_release (record_full_arch_list_tail);
- if (record_debug)
- gdb_printf (gdb_stdlog,
- "Process record: failed to record "
- "execution log.");
- return TARGET_XFER_E_IO;
- }
- record_full_list->next = record_full_arch_list_head;
- record_full_arch_list_head->prev = record_full_list;
- record_full_list = record_full_arch_list_tail;
+ record_full_save_instruction ();
if (record_full_insn_num == record_full_insn_max_num)
record_full_list_release_first ();
@@ -1866,8 +1725,7 @@ record_full_base_target::get_bookmark (const char *args, int from_tty)
char *ret = NULL;
/* Return stringified form of instruction count. */
- if (record_full_list && record_full_list->type == record_full_end)
- ret = xstrdup (pulongest (record_full_list->u.end.insn_num));
+ ret = xstrdup (pulongest (record_full_list[record_full_next_insn].insn_num));
if (record_debug)
{
@@ -1923,30 +1781,22 @@ record_full_base_target::record_method (ptid_t ptid)
void
record_full_base_target::info_record ()
{
- struct record_full_entry *p;
-
if (RECORD_FULL_IS_REPLAY)
gdb_printf (_("Replay mode:\n"));
else
gdb_printf (_("Record mode:\n"));
- /* Find entry for first actual instruction in the log. */
- for (p = record_full_first.next;
- p != NULL && p->type != record_full_end;
- p = p->next)
- ;
-
/* Do we have a log at all? */
- if (p != NULL && p->type == record_full_end)
+ if (!record_full_list.empty ())
{
/* Display instruction number for first instruction in the log. */
- gdb_printf (_("Lowest recorded instruction number is %s.\n"),
- pulongest (p->u.end.insn_num));
+ gdb_printf (_("Lowest recorded instruction number is %u.\n"),
+ record_full_list[0].insn_num);
/* If in replay mode, display where we are in the log. */
if (RECORD_FULL_IS_REPLAY)
- gdb_printf (_("Current instruction number is %s.\n"),
- pulongest (record_full_list->u.end.insn_num));
+ gdb_printf (_("Current instruction number is %u.\n"),
+ record_full_list[record_full_next_insn].insn_num);
/* Display instruction number for last instruction in the log. */
gdb_printf (_("Highest recorded instruction number is %s.\n"),
@@ -1975,7 +1825,7 @@ record_full_base_target::supports_delete_record ()
void
record_full_base_target::delete_record ()
{
- record_full_list_release_following (record_full_list);
+ record_full_reset_history ();
}
/* The "record_is_replaying" target method. */
@@ -2001,23 +1851,23 @@ record_full_base_target::record_will_replay (ptid_t ptid, int dir)
/* Go to a specific entry. */
static void
-record_full_goto_entry (struct record_full_entry *p)
+record_full_goto_entry (size_t target_insn)
{
- if (p == NULL)
+ if (target_insn >= record_full_list.size ())
error (_("Target insn not found."));
- else if (p == record_full_list)
+ else if (target_insn == record_full_next_insn)
error (_("Already at target insn."));
- else if (p->u.end.insn_num > record_full_list->u.end.insn_num)
+ else if (target_insn > record_full_next_insn)
{
gdb_printf (_("Go forward to insn number %s\n"),
- pulongest (p->u.end.insn_num));
- record_full_goto_insn (p, EXEC_FORWARD);
+ pulongest (record_full_list[target_insn].insn_num));
+ record_full_goto_insn (target_insn, EXEC_FORWARD);
}
else
{
gdb_printf (_("Go backward to insn number %s\n"),
- pulongest (p->u.end.insn_num));
- record_full_goto_insn (p, EXEC_REVERSE);
+ pulongest (target_insn));
+ record_full_goto_insn (target_insn, EXEC_REVERSE);
}
registers_changed ();
@@ -2033,13 +1883,7 @@ record_full_goto_entry (struct record_full_entry *p)
void
record_full_base_target::goto_record_begin ()
{
- struct record_full_entry *p = NULL;
-
- for (p = &record_full_first; p != NULL; p = p->next)
- if (p->type == record_full_end)
- break;
-
- record_full_goto_entry (p);
+ record_full_goto_entry (0);
}
/* The "goto_record_end" target method. */
@@ -2047,15 +1891,7 @@ record_full_base_target::goto_record_begin ()
void
record_full_base_target::goto_record_end ()
{
- struct record_full_entry *p = NULL;
-
- for (p = record_full_list; p->next != NULL; p = p->next)
- ;
- for (; p!= NULL; p = p->prev)
- if (p->type == record_full_end)
- break;
-
- record_full_goto_entry (p);
+ record_full_goto_entry (record_full_list.size () -1);
}
/* The "goto_record" target method. */
@@ -2063,13 +1899,7 @@ record_full_base_target::goto_record_end ()
void
record_full_base_target::goto_record (ULONGEST target_insn)
{
- struct record_full_entry *p = NULL;
-
- for (p = &record_full_first; p != NULL; p = p->next)
- if (p->type == record_full_end && p->u.end.insn_num == target_insn)
- break;
-
- record_full_goto_entry (p);
+ record_full_goto_entry (target_insn);
}
/* The "record_stop_replaying" target method. */
@@ -2339,19 +2169,96 @@ netorder32 (uint32_t input)
return ret;
}
+static void
+record_full_read_entry_from_bfd (bfd *cbfd, asection *osec, int *bfd_offset)
+{
+ uint8_t rectype;
+ uint32_t regnum, len;
+ uint64_t addr;
+ regcache *cache = get_thread_regcache (inferior_thread ());
+
+ bfdcore_read (cbfd, osec, &rectype, sizeof (rectype), bfd_offset);
+ switch (rectype)
+ {
+ case record_full_reg: /* reg */
+ {
+ /* Get register number to regnum. */
+ bfdcore_read (cbfd, osec, ®num, sizeof (regnum), bfd_offset);
+ regnum = netorder32 (regnum);
+
+ record_full_entry rec;
+
+ rec = record_full_reg_init (cache, regnum);
+
+ /* Get val. */
+ bfdcore_read (cbfd, osec, record_full_get_loc (&rec),
+ rec.u.reg.len, bfd_offset);
+
+ if (record_debug)
+ gdb_printf (gdb_stdlog,
+ " Reading register %d (1 "
+ "plus %lu plus %d bytes)\n",
+ rec.u.reg.num,
+ (unsigned long) sizeof (regnum),
+ rec.u.reg.len);
+
+ record_full_arch_list_add (rec);
+ break;
+ }
+
+ case record_full_mem: /* mem */
+ {
+ /* Get len. */
+ bfdcore_read (cbfd, osec, &len, sizeof (len), bfd_offset);
+ len = netorder32 (len);
+
+ /* Get addr. */
+ bfdcore_read (cbfd, osec, &addr, sizeof (addr),
+ bfd_offset);
+ addr = netorder64 (addr);
+
+ record_full_entry rec;
+ rec = record_full_mem_init (addr, len);
+
+ /* Get val. */
+ bfdcore_read (cbfd, osec, record_full_get_loc (&rec), len,
+ bfd_offset);
+
+ if (record_debug)
+ gdb_printf (gdb_stdlog,
+ " Reading memory %s (1 plus "
+ "%lu plus %lu plus %d bytes)\n",
+ paddress (get_current_arch (),
+ rec.u.mem.addr),
+ (unsigned long) sizeof (addr),
+ (unsigned long) sizeof (len),
+ len);
+
+ record_full_arch_list_add (rec);
+ break;
+ }
+
+ default:
+ error (_("Bad entry type %d, offset %d of %lu in core file %ps."),
+ rectype, *bfd_offset, bfd_section_size (osec),
+ styled_string (file_name_style.style (),
+ bfd_get_filename (cbfd)));
+ break;
+ }
+}
+
/* Restore the execution log from core file CBFD. */
static void
record_full_restore (struct bfd &cbfd)
{
uint32_t magic;
- struct record_full_entry *rec;
asection *osec;
uint32_t osec_size;
int bfd_offset = 0;
/* "record_full_restore" can only be called when record list is empty. */
- gdb_assert (record_full_first.next == NULL);
+ gdb_assert (record_full_list.empty ());
if (record_debug)
gdb_printf (gdb_stdlog, "Restoring recording from core file.\n");
@@ -2379,124 +2286,47 @@ record_full_restore (struct bfd &cbfd)
"RECORD_FULL_FILE_MAGIC (0x%s)\n",
phex_nz (netorder32 (magic), 4));
- /* Restore the entries in recfd into record_full_arch_list_head and
- record_full_arch_list_tail. */
- record_full_arch_list_head = NULL;
- record_full_arch_list_tail = NULL;
record_full_insn_num = 0;
try
{
- regcache *regcache = get_thread_regcache (inferior_thread ());
-
- while (1)
+ while (bfd_offset < osec_size)
{
- uint8_t rectype;
- uint32_t regnum, len, signal, count;
- uint64_t addr;
-
- /* We are finished when offset reaches osec_size. */
- if (bfd_offset >= osec_size)
- break;
- bfdcore_read (&cbfd, osec, &rectype, sizeof (rectype), &bfd_offset);
-
- switch (rectype)
+ record_full_reset_incomplete ();
+ uint32_t eff_count = 0;
+ uint8_t sigval;
+ uint32_t insn_num;
+
+ /* First read the generic information for an instruction. */
+ bfdcore_read (&cbfd, osec, &sigval, sizeof (uint8_t), &bfd_offset);
+ bfdcore_read (&cbfd, osec, &eff_count, sizeof (uint32_t),
+ &bfd_offset);
+ bfdcore_read (&cbfd, osec, &insn_num, sizeof (uint32_t),
+ &bfd_offset);
+
+ record_full_incomplete_instruction.insn_num = netorder32 (insn_num);
+ if (sigval != GDB_SIGNAL_0)
+ record_full_incomplete_instruction.sigval = (gdb_signal) sigval;
+
+ eff_count = netorder32 (eff_count);
+
+ /* This deals with all the side effects. */
+ while (eff_count > 0)
{
- case record_full_reg: /* reg */
- /* Get register number to regnum. */
- bfdcore_read (&cbfd, osec, ®num, sizeof (regnum),
- &bfd_offset);
- regnum = netorder32 (regnum);
-
- rec = record_full_reg_alloc (regcache, regnum);
-
- /* Get val. */
- bfdcore_read (&cbfd, osec, record_full_get_loc (rec),
- rec->u.reg.len, &bfd_offset);
-
- if (record_debug)
- gdb_printf (gdb_stdlog,
- " Reading register %d (1 "
- "plus %lu plus %d bytes)\n",
- rec->u.reg.num,
- (unsigned long) sizeof (regnum),
- rec->u.reg.len);
- break;
+ eff_count--;
- case record_full_mem: /* mem */
- /* Get len. */
- bfdcore_read (&cbfd, osec, &len, sizeof (len), &bfd_offset);
- len = netorder32 (len);
-
- /* Get addr. */
- bfdcore_read (&cbfd, osec, &addr, sizeof (addr), &bfd_offset);
- addr = netorder64 (addr);
-
- rec = record_full_mem_alloc (addr, len);
-
- /* Get val. */
- bfdcore_read (&cbfd, osec, record_full_get_loc (rec),
- rec->u.mem.len, &bfd_offset);
-
- if (record_debug)
- gdb_printf (gdb_stdlog,
- " Reading memory %s (1 plus "
- "%lu plus %lu plus %d bytes)\n",
- paddress (get_current_arch (),
- rec->u.mem.addr),
- (unsigned long) sizeof (addr),
- (unsigned long) sizeof (len),
- rec->u.mem.len);
- break;
-
- case record_full_end: /* end */
- rec = record_full_end_alloc ();
- record_full_insn_num ++;
-
- /* Get signal value. */
- bfdcore_read (&cbfd, osec, &signal, sizeof (signal),
- &bfd_offset);
- signal = netorder32 (signal);
- rec->u.end.sigval = (enum gdb_signal) signal;
-
- /* Get insn count. */
- bfdcore_read (&cbfd, osec, &count, sizeof (count), &bfd_offset);
- count = netorder32 (count);
- rec->u.end.insn_num = count;
- record_full_insn_count = count + 1;
- if (record_debug)
- gdb_printf (gdb_stdlog,
- " Reading record_full_end (1 + "
- "%lu + %lu bytes), offset == %s\n",
- (unsigned long) sizeof (signal),
- (unsigned long) sizeof (count),
- paddress (get_current_arch (),
- bfd_offset));
- break;
-
- default:
- error (_("Bad entry type in core file %ps."),
- styled_string (file_name_style.style (),
- bfd_get_filename (&cbfd)));
- break;
+ record_full_read_entry_from_bfd (&cbfd, osec, &bfd_offset);
}
- /* Add rec to record arch list. */
- record_full_arch_list_add (rec);
+ record_full_save_instruction ();
}
}
catch (const gdb_exception &ex)
{
- record_full_list_release (record_full_arch_list_tail);
+ record_full_reset_incomplete ();
throw;
}
- /* Add record_full_arch_list_head to the end of record list. */
- record_full_first.next = record_full_arch_list_head;
- record_full_arch_list_head->prev = &record_full_first;
- record_full_arch_list_tail->next = NULL;
- record_full_list = &record_full_first;
-
/* Update record_full_insn_max_num. */
if (record_full_insn_num > record_full_insn_max_num)
{
@@ -2505,6 +2335,10 @@ record_full_restore (struct bfd &cbfd)
record_full_insn_max_num);
}
+ /* When loading a recording, we'll always start at the oldest possible
+ instruction, no matter where the original recording was stopped. */
+ record_full_next_insn = 0;
+
/* Succeeded. */
gdb_printf (_("Restored records from core file %s.\n"),
bfd_get_filename (&cbfd));
@@ -2538,13 +2372,73 @@ cmd_record_full_restore (const char *args, int from_tty)
record_full_open (nullptr, from_tty);
}
+static void
+record_full_write_entry_to_bfd (record_full_entry &entry,
+ gdb_bfd_ref_ptr obfd,
+ asection *osec, int *bfd_offset,
+ struct gdbarch *gdbarch)
+{
+ /* Save entry. */
+ uint8_t type;
+ uint32_t regnum, len;
+ uint64_t addr;
+
+ type = entry.type;
+ bfdcore_write (obfd.get (), osec, &type, sizeof (type), bfd_offset);
+
+ switch (entry.type)
+ {
+ case record_full_reg: /* reg */
+ if (record_debug)
+ gdb_printf (gdb_stdlog,
+ " Writing register %d (1 "
+ "plus %lu plus %d bytes)\n",
+ entry.u.reg.num,
+ (unsigned long) sizeof (regnum),
+ entry.u.reg.len);
+
+ /* Write regnum. */
+ regnum = netorder32 (entry.u.reg.num);
+ bfdcore_write (obfd.get (), osec, ®num, sizeof (regnum), bfd_offset);
+
+ /* Write regval. */
+ bfdcore_write (obfd.get (), osec, record_full_get_loc (&entry),
+ entry.u.reg.len, bfd_offset);
+ break;
+
+ case record_full_mem: /* mem */
+ if (record_debug)
+ gdb_printf (gdb_stdlog,
+ " Writing memory %s (1 plus "
+ "%lu plus %lu plus %d bytes)\n",
+ paddress (gdbarch,
+ entry.u.mem.addr),
+ (unsigned long) sizeof (addr),
+ (unsigned long) sizeof (len),
+ entry.u.mem.len);
+
+ /* Write memlen. */
+ len = netorder32 (entry.u.mem.len);
+ bfdcore_write (obfd.get (), osec, &len, sizeof (len), bfd_offset);
+
+ /* Write memaddr. */
+ addr = netorder64 (entry.u.mem.addr);
+ bfdcore_write (obfd.get (), osec, &addr, sizeof (addr), bfd_offset);
+
+ /* Write memval. */
+ bfdcore_write (obfd.get (), osec, record_full_get_loc (&entry),
+ entry.u.mem.len, bfd_offset);
+ break;
+ }
+
+}
+
/* Save the execution log to a file. We use a modified elf corefile
format, with an extra section for our data. */
void
record_full_base_target::save_record (const char *recfilename)
{
- struct record_full_entry *cur_record_full_list;
uint32_t magic;
struct gdbarch *gdbarch;
int save_size = 0;
@@ -2562,9 +2456,6 @@ record_full_base_target::save_record (const char *recfilename)
/* Arrange to remove the output file on failure. */
gdb::unlinker unlink_file (recfilename);
- /* Save the current record entry to "cur_record_full_list". */
- cur_record_full_list = record_full_list;
-
/* Get the values of regcache and gdbarch. */
regcache *regcache = get_thread_regcache (inferior_thread ());
gdbarch = regcache->arch ();
@@ -2574,34 +2465,27 @@ record_full_base_target::save_record (const char *recfilename)
= record_full_gdb_operation_disable_set ();
/* Reverse execute to the begin of record list. */
- while (1)
- {
- /* Check for beginning and end of log. */
- if (record_full_list == &record_full_first)
- break;
-
- record_full_exec_insn (regcache, gdbarch, record_full_list);
-
- if (record_full_list->prev)
- record_full_list = record_full_list->prev;
- }
+ for (int i = record_full_next_insn - 1; i >= 0; i--)
+ record_full_exec_insn (regcache, gdbarch,
+ record_full_list[i]);
/* Compute the size needed for the extra bfd section. */
save_size = 4; /* magic cookie */
- for (record_full_list = record_full_first.next; record_full_list;
- record_full_list = record_full_list->next)
- switch (record_full_list->type)
- {
- case record_full_end:
- save_size += 1 + 4 + 4;
- break;
- case record_full_reg:
- save_size += 1 + 4 + record_full_list->u.reg.len;
- break;
- case record_full_mem:
- save_size += 1 + 4 + 8 + record_full_list->u.mem.len;
- break;
- }
+ for (int i = record_full_list.size () - 1; i >= 0; i--)
+ {
+ /* Number of effects of an instruction. */
+ save_size += sizeof (uint32_t) + sizeof (uint8_t) + sizeof (uint32_t);
+ for (auto &entry : record_full_list[i].effects)
+ switch (entry.type)
+ {
+ case record_full_reg:
+ save_size += 1 + 4 + entry.u.reg.len;
+ break;
+ case record_full_mem:
+ save_size += 1 + 4 + 8 + entry.u.mem.len;
+ break;
+ }
+ }
/* Make the new bfd section. */
osec = bfd_make_section_anyway_with_flags (obfd.get (), "precord",
@@ -2630,108 +2514,32 @@ record_full_base_target::save_record (const char *recfilename)
/* Save the entries to recfd and forward execute to the end of
record list. */
- record_full_list = &record_full_first;
- while (1)
+ for (int i = 0; i < record_full_list.size (); i++)
{
- /* Save entry. */
- if (record_full_list != &record_full_first)
+ uint32_t eff_count = (uint32_t) record_full_list[i].effects.size ();
+ uint32_t insn_num = record_full_list[i].insn_num;
+ uint8_t sigval = (record_full_list[i].sigval.has_value ())
+ ? record_full_list[i].sigval.value ()
+ : GDB_SIGNAL_0;
+
+ /* Signal. */
+ bfdcore_write (obfd.get (), osec, &sigval, sizeof (sigval), &bfd_offset);
+ eff_count = netorder32 (eff_count);
+ /* Number of effects. */
+ bfdcore_write (obfd.get (), osec, &eff_count, sizeof (eff_count),
+ &bfd_offset);
+ /* Instruction number. */
+ bfdcore_write (obfd.get (), osec, &insn_num, sizeof (uint32_t),
+ &bfd_offset);
+
+ for (auto &entry : record_full_list[i].effects)
{
- uint8_t type;
- uint32_t regnum, len, signal, count;
- uint64_t addr;
-
- type = record_full_list->type;
- bfdcore_write (obfd.get (), osec, &type, sizeof (type), &bfd_offset);
-
- switch (record_full_list->type)
- {
- case record_full_reg: /* reg */
- if (record_debug)
- gdb_printf (gdb_stdlog,
- " Writing register %d (1 "
- "plus %lu plus %d bytes)\n",
- record_full_list->u.reg.num,
- (unsigned long) sizeof (regnum),
- record_full_list->u.reg.len);
-
- /* Write regnum. */
- regnum = netorder32 (record_full_list->u.reg.num);
- bfdcore_write (obfd.get (), osec, ®num,
- sizeof (regnum), &bfd_offset);
-
- /* Write regval. */
- bfdcore_write (obfd.get (), osec,
- record_full_get_loc (record_full_list),
- record_full_list->u.reg.len, &bfd_offset);
- break;
-
- case record_full_mem: /* mem */
- if (record_debug)
- gdb_printf (gdb_stdlog,
- " Writing memory %s (1 plus "
- "%lu plus %lu plus %d bytes)\n",
- paddress (gdbarch,
- record_full_list->u.mem.addr),
- (unsigned long) sizeof (addr),
- (unsigned long) sizeof (len),
- record_full_list->u.mem.len);
-
- /* Write memlen. */
- len = netorder32 (record_full_list->u.mem.len);
- bfdcore_write (obfd.get (), osec, &len, sizeof (len),
- &bfd_offset);
-
- /* Write memaddr. */
- addr = netorder64 (record_full_list->u.mem.addr);
- bfdcore_write (obfd.get (), osec, &addr,
- sizeof (addr), &bfd_offset);
-
- /* Write memval. */
- bfdcore_write (obfd.get (), osec,
- record_full_get_loc (record_full_list),
- record_full_list->u.mem.len, &bfd_offset);
- break;
-
- case record_full_end:
- if (record_debug)
- gdb_printf (gdb_stdlog,
- " Writing record_full_end (1 + "
- "%lu + %lu bytes)\n",
- (unsigned long) sizeof (signal),
- (unsigned long) sizeof (count));
- /* Write signal value. */
- signal = netorder32 (record_full_list->u.end.sigval);
- bfdcore_write (obfd.get (), osec, &signal,
- sizeof (signal), &bfd_offset);
-
- /* Write insn count. */
- count = netorder32 (record_full_list->u.end.insn_num);
- bfdcore_write (obfd.get (), osec, &count,
- sizeof (count), &bfd_offset);
- break;
- }
+ record_full_write_entry_to_bfd (entry, obfd, osec, &bfd_offset,
+ gdbarch);
}
-
/* Execute entry. */
- record_full_exec_insn (regcache, gdbarch, record_full_list);
-
- if (record_full_list->next)
- record_full_list = record_full_list->next;
- else
- break;
- }
-
- /* Reverse execute to cur_record_full_list. */
- while (1)
- {
- /* Check for beginning and end of log. */
- if (record_full_list == cur_record_full_list)
- break;
-
- record_full_exec_insn (regcache, gdbarch, record_full_list);
-
- if (record_full_list->prev)
- record_full_list = record_full_list->prev;
+ if (i < record_full_next_insn)
+ record_full_exec_insn (regcache, gdbarch, record_full_list[i]);
}
unlink_file.keep ();
@@ -2746,7 +2554,7 @@ record_full_base_target::save_record (const char *recfilename)
correspondingly. */
static void
-record_full_goto_insn (struct record_full_entry *entry,
+record_full_goto_insn (size_t target_insn,
enum exec_direction_kind dir)
{
scoped_restore restore_operation_disable
@@ -2757,17 +2565,12 @@ record_full_goto_insn (struct record_full_entry *entry,
/* Assume everything is valid: we will hit the entry,
and we will not hit the end of the recording. */
- if (dir == EXEC_FORWARD)
- record_full_list = record_full_list->next;
-
- do
- {
- record_full_exec_insn (regcache, gdbarch, record_full_list);
- if (dir == EXEC_REVERSE)
- record_full_list = record_full_list->prev;
- else
- record_full_list = record_full_list->next;
- } while (record_full_list != entry);
+ if (dir == EXEC_REVERSE)
+ for (int i = record_full_next_insn; i > target_insn; i--)
+ record_full_exec_insn (regcache, gdbarch, record_full_list[i - 1]);
+ else
+ for (int i = record_full_next_insn; i < target_insn; i++)
+ record_full_exec_insn (regcache, gdbarch, record_full_list[i]);
}
/* Alias for "target record-full". */
@@ -2798,61 +2601,36 @@ set_record_full_insn_max_num (const char *args, int from_tty,
static void
maintenance_print_record_instruction (const char *args, int from_tty)
{
- struct record_full_entry *to_print = record_full_list;
+ if (record_full_list.empty ())
+ error (_("Not enough recorded history"));
+ int offset = record_full_next_insn - 1;
+ /* Reduce the offset by 1 if the record_full_next_insn is after the end
+ so that we show the last recorded instruction instead of crashing. */
+ if (offset == record_full_list.size ())
+ offset--;
if (args != nullptr)
{
- int offset = value_as_long (parse_and_eval (args));
- if (offset > 0)
- {
- /* Move forward OFFSET instructions. We know we found the
- end of an instruction when to_print->type is record_full_end. */
- while (to_print->next != nullptr && offset > 0)
- {
- to_print = to_print->next;
- if (to_print->type == record_full_end)
- offset--;
- }
- if (offset != 0)
- error (_("Not enough recorded history"));
- }
- else
- {
- while (to_print->prev != nullptr && offset < 0)
- {
- to_print = to_print->prev;
- if (to_print->type == record_full_end)
- offset++;
- }
- if (offset != 0)
- error (_("Not enough recorded history"));
- }
+ offset += value_as_long (parse_and_eval (args));
+ if (offset >= record_full_list.size () || offset < 0)
+ error (_("Not enough recorded history"));
}
- gdb_assert (to_print != nullptr);
+ auto to_print = record_full_list.begin () + offset;
gdbarch *arch = current_inferior ()->arch ();
- /* Go back to the start of the instruction. */
- while (to_print->prev != nullptr && to_print->prev->type != record_full_end)
- to_print = to_print->prev;
-
- /* if we're in the first record, there are no actual instructions
- recorded. Warn the user and leave. */
- if (to_print == &record_full_first)
- error (_("Not enough recorded history"));
-
- while (to_print->type != record_full_end)
+ for (auto entry : to_print->effects)
{
- switch (to_print->type)
+ switch (entry.type)
{
case record_full_reg:
{
- type *regtype = gdbarch_register_type (arch, to_print->u.reg.num);
+ type *regtype = gdbarch_register_type (arch, entry.u.reg.num);
value *val
= value_from_contents (regtype,
- record_full_get_loc (to_print));
+ record_full_get_loc (&entry));
gdb_printf ("Register %s changed: ",
- gdbarch_register_name (arch, to_print->u.reg.num));
+ gdbarch_register_name (arch, entry.u.reg.num));
struct value_print_options opts;
get_user_print_options (&opts);
opts.raw = true;
@@ -2862,17 +2640,16 @@ maintenance_print_record_instruction (const char *args, int from_tty)
}
case record_full_mem:
{
- gdb_byte *b = record_full_get_loc (to_print);
+ gdb_byte *b = record_full_get_loc (&entry);
gdb_printf ("%d bytes of memory at address %s changed from:",
- to_print->u.mem.len,
- print_core_address (arch, to_print->u.mem.addr));
- for (int i = 0; i < to_print->u.mem.len; i++)
+ entry.u.mem.len,
+ print_core_address (arch, entry.u.mem.addr));
+ for (int i = 0; i < entry.u.mem.len; i++)
gdb_printf (" %02x", b[i]);
gdb_printf ("\n");
break;
}
}
- to_print = to_print->next;
}
}
@@ -2880,11 +2657,6 @@ INIT_GDB_FILE (record_full)
{
struct cmd_list_element *c;
- /* Init record_full_first. */
- record_full_first.prev = NULL;
- record_full_first.next = NULL;
- record_full_first.type = record_full_end;
-
add_target (record_full_target_info, record_full_open);
add_deprecated_target_alias (record_full_target_info, "record");
add_target (record_full_core_target_info, record_full_open);
diff --git a/gdb/record-full.h b/gdb/record-full.h
index 51effe74560..c327d879a8a 100644
--- a/gdb/record-full.h
+++ b/gdb/record-full.h
@@ -41,7 +41,6 @@ enum record_result
extern int record_full_arch_list_add_reg (struct regcache *regcache, int num);
extern int record_full_arch_list_add_mem (CORE_ADDR addr, int len);
-extern int record_full_arch_list_add_end (void);
/* Returns true if the process record target is open. */
extern int record_full_is_used (void);
diff --git a/gdb/riscv-tdep.c b/gdb/riscv-tdep.c
index 6b5c9c02d46..f5b1f66844c 100644
--- a/gdb/riscv-tdep.c
+++ b/gdb/riscv-tdep.c
@@ -5466,8 +5466,5 @@ riscv_process_record (struct gdbarch *gdbarch, struct regcache *regcache,
if (res != RECORD_SUCCESS)
return res;
- if (record_full_arch_list_add_end ())
- return -1;
-
return 0;
}
diff --git a/gdb/rs6000-tdep.c b/gdb/rs6000-tdep.c
index e135df94a40..f964889a49f 100644
--- a/gdb/rs6000-tdep.c
+++ b/gdb/rs6000-tdep.c
@@ -7138,8 +7138,6 @@ ppc_process_prefix_instruction (int insn_prefix, int insn_suffix,
if (record_full_arch_list_add_reg (regcache, PPC_PC_REGNUM))
return -1;
- if (record_full_arch_list_add_end ())
- return -1;
return 0;
}
@@ -7447,8 +7445,6 @@ ppc_process_record (struct gdbarch *gdbarch, struct regcache *regcache,
if (record_full_arch_list_add_reg (regcache, PPC_PC_REGNUM))
return -1;
- if (record_full_arch_list_add_end ())
- return -1;
return 0;
}
diff --git a/gdb/s390-linux-tdep.c b/gdb/s390-linux-tdep.c
index 3cd6b359d13..6bea30f08dc 100644
--- a/gdb/s390-linux-tdep.c
+++ b/gdb/s390-linux-tdep.c
@@ -910,9 +910,6 @@ s390_linux_record_signal (struct gdbarch *gdbarch, struct regcache *regcache,
if (record_full_arch_list_add_mem (sp, sizeof_rt_sigframe))
return -1;
- if (record_full_arch_list_add_end ())
- return -1;
-
return 0;
}
diff --git a/gdb/s390-tdep.c b/gdb/s390-tdep.c
index f9d7bdd04e4..36ce659ea15 100644
--- a/gdb/s390-tdep.c
+++ b/gdb/s390-tdep.c
@@ -7019,8 +7019,6 @@ s390_process_record (struct gdbarch *gdbarch, struct regcache *regcache,
if (record_full_arch_list_add_reg (regcache, S390_PSWA_REGNUM))
return -1;
- if (record_full_arch_list_add_end ())
- return -1;
return 0;
}
--
2.53.0
^ permalink raw reply [flat|nested] 19+ messages in thread
* [PATCH v2 2/6] gdb/record: remove record_full_insn_num
2026-04-23 15:25 [PATCH v2 0/6] refactor the internals of record-full Guinevere Larsen
2026-04-23 15:25 ` [PATCH v2 1/6] gdb/record: Refactor record history Guinevere Larsen
@ 2026-04-23 15:26 ` Guinevere Larsen
2026-04-23 15:26 ` [PATCH v2 3/6] gdb/record: c++ify internal structures of record-full.c Guinevere Larsen
` (3 subsequent siblings)
5 siblings, 0 replies; 19+ messages in thread
From: Guinevere Larsen @ 2026-04-23 15:26 UTC (permalink / raw)
To: gdb-patches; +Cc: Guinevere Larsen, Thiago Jung Bauermann
Now that record_full_list uses a deque, we don't need a variable to
track the amount of items recorded, so it is just dropped.
Reviewed-by: Thiago Jung Bauermann <thiago.bauermann@linaro.org>
---
gdb/record-full.c | 41 ++++++++++++-----------------------------
1 file changed, 12 insertions(+), 29 deletions(-)
diff --git a/gdb/record-full.c b/gdb/record-full.c
index aac69cee17e..613dd166881 100644
--- a/gdb/record-full.c
+++ b/gdb/record-full.c
@@ -190,8 +190,6 @@ static bool record_full_stop_at_limit = true;
/* Maximum allowed number of insns in execution log. */
static unsigned int record_full_insn_max_num
= DEFAULT_RECORD_FULL_INSN_MAX_NUM;
-/* Actual count of insns presently in execution log. */
-static unsigned int record_full_insn_num = 0;
/* Count of insns logged so far (may be larger
than count of insns presently in execution log). */
static ULONGEST record_full_insn_count;
@@ -459,7 +457,6 @@ record_full_entry_cleanup (struct record_full_entry rec)
static void
record_full_reset_history ()
{
- record_full_insn_num = 0;
record_full_insn_count = 0;
record_full_next_insn = 0;
@@ -497,9 +494,7 @@ record_full_save_instruction ()
}
/* Delete the first instruction from the beginning of the log, to make
- room for adding a new instruction at the end of the log.
-
- Note -- this function does not modify record_full_insn_num. */
+ room for adding a new instruction at the end of the log. */
static void
record_full_list_release_first (void)
@@ -599,7 +594,7 @@ record_full_arch_list_add_mem (CORE_ADDR addr, int len)
static void
record_full_check_insn_num (void)
{
- if (record_full_insn_num == record_full_insn_max_num)
+ if (record_full_list.size () == record_full_insn_max_num)
{
/* Ask user what to do. */
if (record_full_stop_at_limit)
@@ -681,10 +676,8 @@ record_full_message (struct regcache *regcache, enum gdb_signal signal)
record_full_save_instruction ();
- if (record_full_insn_num == record_full_insn_max_num)
+ if (record_full_list.size () == record_full_insn_max_num)
record_full_list_release_first ();
- else
- record_full_insn_num++;
}
static bool
@@ -1461,10 +1454,8 @@ record_full_registers_change (struct regcache *regcache, int regnum)
}
record_full_save_instruction ();
- if (record_full_insn_num == record_full_insn_max_num)
+ if (record_full_list.size () == record_full_insn_max_num)
record_full_list_release_first ();
- else
- record_full_insn_num++;
}
/* "store_registers" method for process record target. */
@@ -1565,10 +1556,8 @@ record_full_target::xfer_partial (enum target_object object,
}
record_full_save_instruction ();
- if (record_full_insn_num == record_full_insn_max_num)
+ if (record_full_list.size () == record_full_insn_max_num)
record_full_list_release_first ();
- else
- record_full_insn_num++;
}
return this->beneath ()->xfer_partial (object, annex, readbuf, writebuf,
@@ -1803,8 +1792,8 @@ record_full_base_target::info_record ()
pulongest (record_full_insn_count));
/* Display log count. */
- gdb_printf (_("Log contains %u instructions.\n"),
- record_full_insn_num);
+ gdb_printf (_("Log contains %lu instructions.\n"),
+ (unsigned long int) record_full_list.size ());
}
else
gdb_printf (_("No instructions have been logged.\n"));
@@ -2286,8 +2275,6 @@ record_full_restore (struct bfd &cbfd)
"RECORD_FULL_FILE_MAGIC (0x%s)\n",
phex_nz (netorder32 (magic), 4));
- record_full_insn_num = 0;
-
try
{
while (bfd_offset < osec_size)
@@ -2328,9 +2315,9 @@ record_full_restore (struct bfd &cbfd)
}
/* Update record_full_insn_max_num. */
- if (record_full_insn_num > record_full_insn_max_num)
+ if (record_full_list.size () > record_full_insn_max_num)
{
- record_full_insn_max_num = record_full_insn_num;
+ record_full_insn_max_num = record_full_list.size ();
warning (_("Auto increase record/replay buffer limit to %u."),
record_full_insn_max_num);
}
@@ -2585,14 +2572,10 @@ static void
set_record_full_insn_max_num (const char *args, int from_tty,
struct cmd_list_element *c)
{
- if (record_full_insn_num > record_full_insn_max_num)
+ if (record_full_list.size () > record_full_insn_max_num)
{
- /* Count down record_full_insn_num while releasing records from list. */
- while (record_full_insn_num > record_full_insn_max_num)
- {
- record_full_list_release_first ();
- record_full_insn_num--;
- }
+ while (record_full_list.size () > record_full_insn_max_num)
+ record_full_list_release_first ();
}
}
--
2.53.0
^ permalink raw reply [flat|nested] 19+ messages in thread
* [PATCH v2 3/6] gdb/record: c++ify internal structures of record-full.c
2026-04-23 15:25 [PATCH v2 0/6] refactor the internals of record-full Guinevere Larsen
2026-04-23 15:25 ` [PATCH v2 1/6] gdb/record: Refactor record history Guinevere Larsen
2026-04-23 15:26 ` [PATCH v2 2/6] gdb/record: remove record_full_insn_num Guinevere Larsen
@ 2026-04-23 15:26 ` Guinevere Larsen
2026-04-28 3:29 ` Thiago Jung Bauermann
2026-04-23 15:26 ` [PATCH v2 4/6] gdb/record: make record_full_history more c++-like Guinevere Larsen
` (2 subsequent siblings)
5 siblings, 1 reply; 19+ messages in thread
From: Guinevere Larsen @ 2026-04-23 15:26 UTC (permalink / raw)
To: gdb-patches; +Cc: Guinevere Larsen
This commit adds a constructor, destructor, and some methods to the
structures record_full_entry, record_full_reg_entry and
record_full_mem_entry. This is a move to disentangle the internal
representation of the data and how record-full manipulates it for
replaying.
Along with this change, record_full_entry is changed to use an
std::variant, since it was basically doing that already, but now we have
the stdlibc++ error checking to make sure we're only accessing elements
we're allowed to.
---
gdb/record-full.c | 553 ++++++++++++++++++++++++----------------------
1 file changed, 289 insertions(+), 264 deletions(-)
diff --git a/gdb/record-full.c b/gdb/record-full.c
index 613dd166881..6e3907325cd 100644
--- a/gdb/record-full.c
+++ b/gdb/record-full.c
@@ -48,6 +48,7 @@
#include "cli/cli-style.h"
#include <signal.h>
+#include <variant>
/* This module implements "target record-full", also known as "process
record and replay". This target sits on top of a "normal" target
@@ -90,12 +91,92 @@ struct record_full_mem_entry
int len;
/* Set this flag if target memory for this entry
can no longer be accessed. */
- int mem_entry_not_accessible;
+ bool mem_entry_accessible;
union
{
gdb_byte *ptr;
gdb_byte buf[sizeof (gdb_byte *)];
} u;
+
+ record_full_mem_entry () : addr (0), len (0) { }
+
+ record_full_mem_entry (CORE_ADDR mem_addr, int mem_len)
+ {
+ addr = mem_addr;
+ len = mem_len;
+ if (len > sizeof (u.buf))
+ u.ptr = new gdb_byte[len];
+ mem_entry_accessible = true;
+ }
+
+ gdb_byte *get_loc ()
+ {
+ if (len > sizeof (u.buf))
+ return u.ptr;
+ else
+ return u.buf;
+ }
+
+ bool execute (gdbarch *gdbarch)
+ {
+ /* Nothing to do if the memory is flagged not_accessible. */
+ if (!mem_entry_accessible)
+ return false;
+
+ gdb::byte_vector buf (len);
+
+ if (record_debug > 1)
+ gdb_printf (gdb_stdlog,
+ "Process record: record_full_mem %s to "
+ "inferior addr = %s len = %d.\n",
+ host_address_to_string (this),
+ paddress (gdbarch, addr),
+ len);
+
+ if (record_read_memory (gdbarch, addr, buf.data (), len))
+ mem_entry_accessible = false;
+ else
+ {
+ if (target_write_memory (addr,
+ get_loc (),
+ len))
+ {
+ mem_entry_accessible = false;
+ if (record_debug)
+ warning (_("Process record: error writing memory at "
+ "addr = %s len = %d."),
+ paddress (gdbarch, addr),
+ len);
+ }
+ else
+ {
+ memcpy (get_loc (), buf.data (), len);
+
+ /* We've changed memory --- check if a hardware
+ watchpoint should trap. Note that this
+ presently assumes the target beneath supports
+ continuable watchpoints. On non-continuable
+ watchpoints target, we'll want to check this
+ _before_ actually doing the memory change, and
+ not doing the change at all if the watchpoint
+ traps. */
+ if (hardware_watchpoint_inserted_in_range
+ (current_inferior ()->aspace.get (), addr, len))
+ return true;
+ }
+ }
+ return false;
+ }
+
+ /* Cleanup this entry. This would ideally be a destructor for the class,
+ but I kept running into issues with double free, so this is left as a
+ future improvement. */
+
+ void cleanup ()
+ {
+ if (len > sizeof (u.buf))
+ delete u.ptr;
+ }
};
struct record_full_reg_entry
@@ -107,6 +188,51 @@ struct record_full_reg_entry
gdb_byte *ptr;
gdb_byte buf[2 * sizeof (gdb_byte *)];
} u;
+
+ record_full_reg_entry () : num (0), len (0) { }
+
+ record_full_reg_entry (gdbarch *gdbarch, int regnum)
+ {
+ num = regnum;
+ len = register_size (gdbarch, regnum);
+ if (len > sizeof (u.buf))
+ u.ptr = new gdb_byte[len];
+ }
+
+ gdb_byte *get_loc ()
+ {
+ if (len > sizeof (u.buf))
+ return u.ptr;
+ else
+ return u.buf;
+ }
+
+ bool execute (regcache *regcache)
+ {
+ gdb::byte_vector buf (len);
+
+ if (record_debug > 1)
+ gdb_printf (gdb_stdlog,
+ "Process record: record_full_reg %s to "
+ "inferior num = %d.\n",
+ host_address_to_string (this),
+ num);
+
+ regcache->cooked_read (num, buf);
+ regcache->cooked_write (num, get_loc ());
+ memcpy (get_loc (), buf.data (), len);
+ return false;
+ }
+
+ /* Cleanup this entry. This would ideally be a destructor for the class,
+ but I kept running into issues with double free, so this is left as a
+ future improvement. */
+
+ void cleanup ()
+ {
+ if (len > sizeof (u.buf))
+ delete u.ptr;
+ }
};
enum record_full_type
@@ -115,16 +241,96 @@ enum record_full_type
record_full_mem
};
-struct record_full_entry
+class record_full_entry
{
- enum record_full_type type;
- union
+ std::variant<record_full_reg_entry, record_full_mem_entry> entry;
+
+public:
+ record_full_entry () : entry (record_full_reg_entry ()) {}
+
+ /* Constructor for a register entry. Type is here to make it
+ easier to recognize it in the constructor calls, it isn't
+ actually important. */
+ record_full_entry (record_full_type reg_type, gdbarch *gdbarch,
+ int regnum)
+ : entry(record_full_reg_entry (gdbarch, regnum))
{
- /* reg */
- struct record_full_reg_entry reg;
- /* mem */
- struct record_full_mem_entry mem;
- } u;
+ gdb_assert (reg_type == record_full_reg);
+ }
+
+ record_full_entry (record_full_type mem_type, CORE_ADDR addr, int len)
+ : entry(record_full_mem_entry (addr, len))
+ {
+ gdb_assert (mem_type == record_full_mem);
+ }
+
+ record_full_reg_entry& reg ()
+ {
+ gdb_assert (type () == record_full_reg);
+ return std::get<record_full_reg_entry> (entry);
+ }
+
+ record_full_mem_entry& mem ()
+ {
+ gdb_assert (type () == record_full_mem);
+ return std::get<record_full_mem_entry> (entry);
+ }
+
+ record_full_type type ()
+ {
+ switch (entry.index ())
+ {
+ case 0:
+ return record_full_reg;
+ case 1:
+ return record_full_mem;
+ }
+ gdb_assert_not_reached ("Impossible variant index");
+ }
+
+ /* Get the pointer to the data stored by this entry. */
+ gdb_byte *get_loc ()
+ {
+ switch (type ())
+ {
+ case record_full_reg:
+ return reg ().get_loc ();
+ case record_full_mem:
+ return mem ().get_loc ();
+ }
+ gdb_assert_not_reached ("Impossible entry type");
+ }
+
+ /* Execute this entry, swapping the appropriate values from memory or
+ register and the recorded ones. Returns TRUE if the execution was
+ stopped by a watchpoint. */
+
+ bool execute (regcache *regcache)
+ {
+ switch (type ())
+ {
+ case record_full_reg:
+ return reg ().execute (regcache);
+ case record_full_mem:
+ return mem ().execute (regcache->arch ());
+ }
+ return false;
+ }
+
+ /* Free one record entry, any type. */
+
+ void cleanup ()
+ {
+ switch (type ())
+ {
+ case record_full_reg:
+ reg ().cleanup ();
+ break;
+ case record_full_mem:
+ mem ().cleanup ();
+ break;
+ }
+ }
};
/* This is the main structure that comprises the execution log.
@@ -381,79 +587,6 @@ static struct cmd_list_element *record_full_cmdlist;
static void record_full_goto_insn (size_t target_insn,
enum exec_direction_kind dir);
-/* Initialization and cleanup functions for record_full_reg and
- record_full_mem entries. */
-
-/* Init a record_full_reg record entry. */
-
-static inline struct record_full_entry
-record_full_reg_init (struct regcache *regcache, int regnum)
-{
- struct record_full_entry rec;
- struct gdbarch *gdbarch = regcache->arch ();
-
- rec.type = record_full_reg;
- rec.u.reg.num = regnum;
- rec.u.reg.len = register_size (gdbarch, regnum);
- if (rec.u.reg.len > sizeof (rec.u.reg.u.buf))
- rec.u.reg.u.ptr = (gdb_byte *) xmalloc (rec.u.reg.len);
-
- return rec;
-}
-
-/* Cleanup a record_full_reg record entry. */
-
-static inline void
-record_full_reg_cleanup (struct record_full_entry rec)
-{
- gdb_assert (rec.type == record_full_reg);
- if (rec.u.reg.len > sizeof (rec.u.reg.u.buf))
- xfree (rec.u.reg.u.ptr);
-}
-
-/* Init a record_full_mem record entry. */
-
-static inline struct record_full_entry
-record_full_mem_init (CORE_ADDR addr, int len)
-{
- struct record_full_entry rec;
-
- rec.type = record_full_mem;
- rec.u.mem.addr = addr;
- rec.u.mem.len = len;
- if (rec.u.mem.len > sizeof (rec.u.mem.u.buf))
- rec.u.mem.u.ptr = (gdb_byte *) xmalloc (len);
- rec.u.mem.mem_entry_not_accessible = 0;
-
- return rec;
-}
-
-/* Cleanup a record_full_mem record entry. */
-
-static inline void
-record_full_mem_cleanup (struct record_full_entry rec)
-{
- gdb_assert (rec.type == record_full_mem);
- if (rec.u.mem.len > sizeof (rec.u.mem.u.buf))
- xfree (rec.u.mem.u.ptr);
-}
-
-/* Free one record entry, any type. */
-
-static inline void
-record_full_entry_cleanup (struct record_full_entry rec)
-{
-
- switch (rec.type) {
- case record_full_reg:
- record_full_reg_cleanup (rec);
- break;
- case record_full_mem:
- record_full_mem_cleanup (rec);
- break;
- }
-}
-
static void
record_full_reset_history ()
{
@@ -463,7 +596,7 @@ record_full_reset_history ()
for (auto &insn : record_full_list)
{
for (auto &entry : insn.effects)
- record_full_entry_cleanup (entry);
+ entry.cleanup ();
}
record_full_list.clear ();
@@ -475,7 +608,7 @@ record_full_list_release_following (int index)
for (int i = record_full_list.size () - 1; i > index; i--)
{
for (auto &entry : record_full_list[i].effects)
- record_full_entry_cleanup (entry);
+ entry.cleanup ();
record_full_list.pop_back ();
}
/* Set the next instruction to be past the end of the log so we
@@ -503,7 +636,7 @@ record_full_list_release_first (void)
return;
for (auto &entry : record_full_list[0].effects)
- record_full_entry_cleanup (entry);
+ entry.cleanup ();
record_full_list.pop_front ();
--record_full_next_insn;
@@ -517,33 +650,12 @@ record_full_arch_list_add (struct record_full_entry &rec)
record_full_incomplete_instruction.effects.push_back (rec);
}
-/* Return the value storage location of a record entry. */
-static inline gdb_byte *
-record_full_get_loc (struct record_full_entry *rec)
-{
- switch (rec->type) {
- case record_full_mem:
- if (rec->u.mem.len > sizeof (rec->u.mem.u.buf))
- return rec->u.mem.u.ptr;
- else
- return rec->u.mem.u.buf;
- case record_full_reg:
- if (rec->u.reg.len > sizeof (rec->u.reg.u.buf))
- return rec->u.reg.u.ptr;
- else
- return rec->u.reg.u.buf;
- default:
- gdb_assert_not_reached ("unexpected record_full_entry type");
- return NULL;
- }
-}
-
/* Record the value of a register NUM to record_full_arch_list. */
int
record_full_arch_list_add_reg (struct regcache *regcache, int regnum)
{
- struct record_full_entry rec;
+ struct record_full_entry rec (record_full_reg, regcache->arch (), regnum);
if (record_debug > 1)
gdb_printf (gdb_stdlog,
@@ -551,9 +663,7 @@ record_full_arch_list_add_reg (struct regcache *regcache, int regnum)
"record list.\n",
regnum);
- rec = record_full_reg_init (regcache, regnum);
-
- regcache->cooked_read (regnum, record_full_get_loc (&rec));
+ regcache->cooked_read (regnum, rec.get_loc ());
record_full_arch_list_add (rec);
@@ -566,7 +676,7 @@ record_full_arch_list_add_reg (struct regcache *regcache, int regnum)
int
record_full_arch_list_add_mem (CORE_ADDR addr, int len)
{
- struct record_full_entry rec;
+ struct record_full_entry rec (record_full_mem, addr, len);
if (record_debug > 1)
gdb_printf (gdb_stdlog,
@@ -577,12 +687,10 @@ record_full_arch_list_add_mem (CORE_ADDR addr, int len)
if (!addr) /* FIXME: Why? Some arch must permit it... */
return 0;
- rec = record_full_mem_init (addr, len);
-
if (record_read_memory (current_inferior ()->arch (), addr,
- record_full_get_loc (&rec), len))
+ rec.get_loc (), len))
{
- record_full_mem_cleanup (rec);
+ rec.cleanup ();
return -1;
}
@@ -712,98 +820,14 @@ record_full_gdb_operation_disable_set (void)
static enum target_stop_reason record_full_stop_reason
= TARGET_STOPPED_BY_NO_REASON;
-/* Execute one instruction from the record log. Each instruction in
- the log will be represented by an arbitrary sequence of register
- entries and memory entries, followed by an 'end' entry. */
-
-static inline void
-record_full_exec_entry (struct regcache *regcache,
- struct gdbarch *gdbarch,
- struct record_full_entry *entry)
-{
- switch (entry->type)
- {
- case record_full_reg: /* reg */
- {
- gdb::byte_vector reg (entry->u.reg.len);
-
- if (record_debug > 1)
- gdb_printf (gdb_stdlog,
- "Process record: record_full_reg %s to "
- "inferior num = %d.\n",
- host_address_to_string (entry),
- entry->u.reg.num);
-
- regcache->cooked_read (entry->u.reg.num, reg.data ());
- regcache->cooked_write (entry->u.reg.num, record_full_get_loc (entry));
- memcpy (record_full_get_loc (entry), reg.data (), entry->u.reg.len);
- }
- break;
-
- case record_full_mem: /* mem */
- {
- /* Nothing to do if the entry is flagged not_accessible. */
- if (!entry->u.mem.mem_entry_not_accessible)
- {
- gdb::byte_vector mem (entry->u.mem.len);
-
- if (record_debug > 1)
- gdb_printf (gdb_stdlog,
- "Process record: record_full_mem %s to "
- "inferior addr = %s len = %d.\n",
- host_address_to_string (entry),
- paddress (gdbarch, entry->u.mem.addr),
- entry->u.mem.len);
-
- if (record_read_memory (gdbarch,
- entry->u.mem.addr, mem.data (),
- entry->u.mem.len))
- entry->u.mem.mem_entry_not_accessible = 1;
- else
- {
- if (target_write_memory (entry->u.mem.addr,
- record_full_get_loc (entry),
- entry->u.mem.len))
- {
- entry->u.mem.mem_entry_not_accessible = 1;
- if (record_debug)
- warning (_("Process record: error writing memory at "
- "addr = %s len = %d."),
- paddress (gdbarch, entry->u.mem.addr),
- entry->u.mem.len);
- }
- else
- {
- memcpy (record_full_get_loc (entry), mem.data (),
- entry->u.mem.len);
-
- /* We've changed memory --- check if a hardware
- watchpoint should trap. Note that this
- presently assumes the target beneath supports
- continuable watchpoints. On non-continuable
- watchpoints target, we'll want to check this
- _before_ actually doing the memory change, and
- not doing the change at all if the watchpoint
- traps. */
- if (hardware_watchpoint_inserted_in_range
- (current_inferior ()->aspace.get (),
- entry->u.mem.addr, entry->u.mem.len))
- record_full_stop_reason = TARGET_STOPPED_BY_WATCHPOINT;
- }
- }
- }
- }
- break;
- }
-}
-
static inline void
record_full_exec_insn (struct regcache *regcache,
struct gdbarch *gdbarch,
record_full_instruction &insn)
{
for (auto &entry : insn.effects)
- record_full_exec_entry (regcache, gdbarch, &entry);
+ if (entry.execute (regcache))
+ record_full_stop_reason = TARGET_STOPPED_BY_WATCHPOINT;
}
static void record_full_restore (struct bfd &cbfd);
@@ -2175,21 +2199,19 @@ record_full_read_entry_from_bfd (bfd *cbfd, asection *osec, int *bfd_offset)
bfdcore_read (cbfd, osec, ®num, sizeof (regnum), bfd_offset);
regnum = netorder32 (regnum);
- record_full_entry rec;
-
- rec = record_full_reg_init (cache, regnum);
+ record_full_entry rec (record_full_reg, cache->arch (), regnum);
/* Get val. */
- bfdcore_read (cbfd, osec, record_full_get_loc (&rec),
- rec.u.reg.len, bfd_offset);
+ bfdcore_read (cbfd, osec, rec.get_loc (),
+ rec.reg ().len, bfd_offset);
if (record_debug)
gdb_printf (gdb_stdlog,
" Reading register %d (1 "
"plus %lu plus %d bytes)\n",
- rec.u.reg.num,
+ rec.reg ().num,
(unsigned long) sizeof (regnum),
- rec.u.reg.len);
+ rec.reg ().len);
record_full_arch_list_add (rec);
break;
@@ -2206,19 +2228,17 @@ record_full_read_entry_from_bfd (bfd *cbfd, asection *osec, int *bfd_offset)
bfd_offset);
addr = netorder64 (addr);
- record_full_entry rec;
- rec = record_full_mem_init (addr, len);
+ record_full_entry rec (record_full_mem, addr, len);
/* Get val. */
- bfdcore_read (cbfd, osec, record_full_get_loc (&rec), len,
- bfd_offset);
+ bfdcore_read (cbfd, osec, rec.get_loc (), len, bfd_offset);
if (record_debug)
gdb_printf (gdb_stdlog,
" Reading memory %s (1 plus "
"%lu plus %lu plus %d bytes)\n",
paddress (get_current_arch (),
- rec.u.mem.addr),
+ rec.mem ().addr),
(unsigned long) sizeof (addr),
(unsigned long) sizeof (len),
len);
@@ -2370,52 +2390,56 @@ record_full_write_entry_to_bfd (record_full_entry &entry,
uint32_t regnum, len;
uint64_t addr;
- type = entry.type;
+ type = entry.type ();
bfdcore_write (obfd.get (), osec, &type, sizeof (type), bfd_offset);
- switch (entry.type)
+ switch (type)
{
case record_full_reg: /* reg */
- if (record_debug)
- gdb_printf (gdb_stdlog,
- " Writing register %d (1 "
- "plus %lu plus %d bytes)\n",
- entry.u.reg.num,
- (unsigned long) sizeof (regnum),
- entry.u.reg.len);
-
- /* Write regnum. */
- regnum = netorder32 (entry.u.reg.num);
- bfdcore_write (obfd.get (), osec, ®num, sizeof (regnum), bfd_offset);
-
- /* Write regval. */
- bfdcore_write (obfd.get (), osec, record_full_get_loc (&entry),
- entry.u.reg.len, bfd_offset);
- break;
+ {
+ auto reg = entry.reg ();
+ if (record_debug)
+ gdb_printf (gdb_stdlog,
+ " Writing register %d (1 "
+ "plus %lu plus %d bytes)\n",
+ reg.num,
+ (unsigned long) sizeof (regnum),
+ reg.len);
+
+ /* Write regnum. */
+ regnum = netorder32 (reg.num);
+ bfdcore_write (obfd.get (), osec, ®num, sizeof (regnum), bfd_offset);
+
+ /* Write regval. */
+ bfdcore_write (obfd.get (), osec, entry.get_loc (), reg.len, bfd_offset);
+ break;
+ }
case record_full_mem: /* mem */
- if (record_debug)
- gdb_printf (gdb_stdlog,
- " Writing memory %s (1 plus "
- "%lu plus %lu plus %d bytes)\n",
- paddress (gdbarch,
- entry.u.mem.addr),
- (unsigned long) sizeof (addr),
- (unsigned long) sizeof (len),
- entry.u.mem.len);
-
- /* Write memlen. */
- len = netorder32 (entry.u.mem.len);
- bfdcore_write (obfd.get (), osec, &len, sizeof (len), bfd_offset);
-
- /* Write memaddr. */
- addr = netorder64 (entry.u.mem.addr);
- bfdcore_write (obfd.get (), osec, &addr, sizeof (addr), bfd_offset);
-
- /* Write memval. */
- bfdcore_write (obfd.get (), osec, record_full_get_loc (&entry),
- entry.u.mem.len, bfd_offset);
- break;
+ {
+ auto mem = entry.mem ();
+ if (record_debug)
+ gdb_printf (gdb_stdlog,
+ " Writing memory %s (1 plus "
+ "%lu plus %lu plus %d bytes)\n",
+ paddress (gdbarch, mem.addr),
+ (unsigned long) sizeof (addr),
+ (unsigned long) sizeof (len),
+ mem.len);
+
+ /* Write memlen. */
+ len = netorder32 (mem.len);
+ bfdcore_write (obfd.get (), osec, &len, sizeof (len), bfd_offset);
+
+ /* Write memaddr. */
+ addr = netorder64 (mem.addr);
+ bfdcore_write (obfd.get (), osec, &addr, sizeof (addr), bfd_offset);
+
+ /* Write memval. */
+ bfdcore_write (obfd.get (), osec, entry.get_loc (), mem.len,
+ bfd_offset);
+ break;
+ }
}
}
@@ -2463,13 +2487,13 @@ record_full_base_target::save_record (const char *recfilename)
/* Number of effects of an instruction. */
save_size += sizeof (uint32_t) + sizeof (uint8_t) + sizeof (uint32_t);
for (auto &entry : record_full_list[i].effects)
- switch (entry.type)
+ switch (entry.type ())
{
case record_full_reg:
- save_size += 1 + 4 + entry.u.reg.len;
+ save_size += 1 + 4 + entry.reg ().len;
break;
case record_full_mem:
- save_size += 1 + 4 + 8 + entry.u.mem.len;
+ save_size += 1 + 4 + 8 + entry.mem ().len;
break;
}
}
@@ -2604,16 +2628,16 @@ maintenance_print_record_instruction (const char *args, int from_tty)
for (auto entry : to_print->effects)
{
- switch (entry.type)
+ switch (entry.type ())
{
case record_full_reg:
{
- type *regtype = gdbarch_register_type (arch, entry.u.reg.num);
+ type *regtype = gdbarch_register_type (arch, entry.reg ().num);
value *val
= value_from_contents (regtype,
- record_full_get_loc (&entry));
+ entry.get_loc ());
gdb_printf ("Register %s changed: ",
- gdbarch_register_name (arch, entry.u.reg.num));
+ gdbarch_register_name (arch, entry.reg ().num));
struct value_print_options opts;
get_user_print_options (&opts);
opts.raw = true;
@@ -2623,11 +2647,12 @@ maintenance_print_record_instruction (const char *args, int from_tty)
}
case record_full_mem:
{
- gdb_byte *b = record_full_get_loc (&entry);
+ record_full_mem_entry& mem = entry.mem ();
+ gdb_byte *b = entry.get_loc ();
gdb_printf ("%d bytes of memory at address %s changed from:",
- entry.u.mem.len,
- print_core_address (arch, entry.u.mem.addr));
- for (int i = 0; i < entry.u.mem.len; i++)
+ mem.len,
+ print_core_address (arch, mem.addr));
+ for (int i = 0; i < mem.len; i++)
gdb_printf (" %02x", b[i]);
gdb_printf ("\n");
break;
--
2.53.0
^ permalink raw reply [flat|nested] 19+ messages in thread
* [PATCH v2 4/6] gdb/record: make record_full_history more c++-like
2026-04-23 15:25 [PATCH v2 0/6] refactor the internals of record-full Guinevere Larsen
` (2 preceding siblings ...)
2026-04-23 15:26 ` [PATCH v2 3/6] gdb/record: c++ify internal structures of record-full.c Guinevere Larsen
@ 2026-04-23 15:26 ` Guinevere Larsen
2026-04-28 3:29 ` Thiago Jung Bauermann
2026-04-23 15:26 ` [PATCH v2 5/6] gdb/record: extract the PC to record_full_instruction Guinevere Larsen
2026-04-23 15:26 ` [PATCH v2 6/6] gdb/record: Define new version of the record-save section Guinevere Larsen
5 siblings, 1 reply; 19+ messages in thread
From: Guinevere Larsen @ 2026-04-23 15:26 UTC (permalink / raw)
To: gdb-patches; +Cc: Guinevere Larsen
Move some functions to being a method of record_full_history, instead of
floating functions.
---
gdb/record-full.c | 25 +++++++++++--------------
1 file changed, 11 insertions(+), 14 deletions(-)
diff --git a/gdb/record-full.c b/gdb/record-full.c
index 6e3907325cd..d0cd8b66174 100644
--- a/gdb/record-full.c
+++ b/gdb/record-full.c
@@ -353,6 +353,10 @@ struct record_full_instruction
uint32_t insn_num;
std::optional<gdb_signal> sigval;
std::vector<record_full_entry> effects;
+
+ /* Execute the full instruction. As a side effect, set
+ record_full_stop_reason. */
+ void exec_insn (regcache *regcache);
};
/* If true, query if PREC cannot record memory
@@ -820,12 +824,9 @@ record_full_gdb_operation_disable_set (void)
static enum target_stop_reason record_full_stop_reason
= TARGET_STOPPED_BY_NO_REASON;
-static inline void
-record_full_exec_insn (struct regcache *regcache,
- struct gdbarch *gdbarch,
- record_full_instruction &insn)
+void record_full_instruction::exec_insn (regcache *regcache)
{
- for (auto &entry : insn.effects)
+ for (auto &entry : effects)
if (entry.execute (regcache))
record_full_stop_reason = TARGET_STOPPED_BY_WATCHPOINT;
}
@@ -1285,9 +1286,7 @@ record_full_wait_1 (struct target_ops *ops,
break;
}
- record_full_exec_insn
- (regcache, gdbarch,
- record_full_list[record_full_next_insn]);
+ record_full_list[record_full_next_insn].exec_insn (regcache);
/* step */
if (record_full_resume_step)
@@ -2477,8 +2476,7 @@ record_full_base_target::save_record (const char *recfilename)
/* Reverse execute to the begin of record list. */
for (int i = record_full_next_insn - 1; i >= 0; i--)
- record_full_exec_insn (regcache, gdbarch,
- record_full_list[i]);
+ record_full_list[i].exec_insn (regcache);
/* Compute the size needed for the extra bfd section. */
save_size = 4; /* magic cookie */
@@ -2550,7 +2548,7 @@ record_full_base_target::save_record (const char *recfilename)
}
/* Execute entry. */
if (i < record_full_next_insn)
- record_full_exec_insn (regcache, gdbarch, record_full_list[i]);
+ record_full_list[i].exec_insn (regcache);
}
unlink_file.keep ();
@@ -2571,17 +2569,16 @@ record_full_goto_insn (size_t target_insn,
scoped_restore restore_operation_disable
= record_full_gdb_operation_disable_set ();
regcache *regcache = get_thread_regcache (inferior_thread ());
- struct gdbarch *gdbarch = regcache->arch ();
/* Assume everything is valid: we will hit the entry,
and we will not hit the end of the recording. */
if (dir == EXEC_REVERSE)
for (int i = record_full_next_insn; i > target_insn; i--)
- record_full_exec_insn (regcache, gdbarch, record_full_list[i - 1]);
+ record_full_list[i-1].exec_insn (regcache);
else
for (int i = record_full_next_insn; i < target_insn; i++)
- record_full_exec_insn (regcache, gdbarch, record_full_list[i]);
+ record_full_list[i].exec_insn (regcache);
}
/* Alias for "target record-full". */
--
2.53.0
^ permalink raw reply [flat|nested] 19+ messages in thread
* [PATCH v2 5/6] gdb/record: extract the PC to record_full_instruction
2026-04-23 15:25 [PATCH v2 0/6] refactor the internals of record-full Guinevere Larsen
` (3 preceding siblings ...)
2026-04-23 15:26 ` [PATCH v2 4/6] gdb/record: make record_full_history more c++-like Guinevere Larsen
@ 2026-04-23 15:26 ` Guinevere Larsen
2026-04-28 3:30 ` Thiago Jung Bauermann
2026-04-23 15:26 ` [PATCH v2 6/6] gdb/record: Define new version of the record-save section Guinevere Larsen
5 siblings, 1 reply; 19+ messages in thread
From: Guinevere Larsen @ 2026-04-23 15:26 UTC (permalink / raw)
To: gdb-patches; +Cc: Guinevere Larsen
This commit makes it so the PC is not saved as part of the
record_full_instruction effects, but rather gets a special location.
That is because a couple of commands would really benefit from it being
easy to find the PC (especially ones from record-btrace that's haven't
been implemented to record-full yet, such as the ones in PR
record/18059), while also possibly allowing for one fewer resizing of
the effect vector (and saving an entire byte in the process).
This commit also refactored record_full_read_entry_from_bfd and
record_full_write_entry_to_bfd, to make them methods of
record_full_reg_entry and record_full_mem_entry, and also creates
similar methods for record_full_entry and record_full_instruction.
These could be turned into constructors in a future step of
c++ification, but it felt like too much change for a single commit.
---
gdb/record-full.c | 384 ++++++++++++++++++++++++++++------------------
1 file changed, 237 insertions(+), 147 deletions(-)
diff --git a/gdb/record-full.c b/gdb/record-full.c
index d0cd8b66174..05d515f5295 100644
--- a/gdb/record-full.c
+++ b/gdb/record-full.c
@@ -109,6 +109,14 @@ struct record_full_mem_entry
mem_entry_accessible = true;
}
+ /* Create a mem_entry from a bfd file, when restoring a recording. */
+ static record_full_mem_entry from_bfd (bfd *cbfd, asection* osec,
+ int *bfd_offset);
+
+ /* Save this mem entry to a bfd file. */
+ void to_bfd (gdb_bfd_ref_ptr obfd, asection *osec, int *bfd_offset,
+ gdbarch *gdbarch);
+
gdb_byte *get_loc ()
{
if (len > sizeof (u.buf))
@@ -199,6 +207,14 @@ struct record_full_reg_entry
u.ptr = new gdb_byte[len];
}
+ /* Create a reg_entry from a bfd file, when restoring a recording. */
+ static record_full_reg_entry from_bfd (bfd *cbfd, asection* osec,
+ int *bfd_offset);
+
+ /* Save this reg entry to a bfd file. */
+ void to_bfd (gdb_bfd_ref_ptr obfd, asection *osec, int *bfd_offset,
+ gdbarch *gdbarch);
+
gdb_byte *get_loc ()
{
if (len > sizeof (u.buf))
@@ -264,6 +280,13 @@ class record_full_entry
gdb_assert (mem_type == record_full_mem);
}
+ /* Create a generic entry from a bfd file, when restoring a recording. */
+ static void from_bfd (bfd *cbfd, asection* osec, int *bfd_offset);
+
+ /* Save this entry to a bfd file. */
+ void to_bfd (gdb_bfd_ref_ptr obfd, asection *osec, int *bfd_offset,
+ gdbarch *gdbarch);
+
record_full_reg_entry& reg ()
{
gdb_assert (type () == record_full_reg);
@@ -339,6 +362,7 @@ class record_full_entry
this one;
* sigval: Whether the inferior received a signal while the following
instruction was being recorded;
+ * pc: The Program Counter for where the instruction starts;
* effects: A list of record_full_entry structures, each of which
describing one effect that the instruction has on the inferior.
@@ -353,10 +377,18 @@ struct record_full_instruction
uint32_t insn_num;
std::optional<gdb_signal> sigval;
std::vector<record_full_entry> effects;
+ record_full_reg_entry pc;
/* Execute the full instruction. As a side effect, set
record_full_stop_reason. */
void exec_insn (regcache *regcache);
+
+ /* Create a full recorded instruction from a bfd. */
+ static void from_bfd (bfd *cbfd, asection* osec, int *bfd_offset);
+
+ /* Save this instruction to a bfd file. */
+ void to_bfd (gdb_bfd_ref_ptr obfd, asection *osec, int *bfd_offset,
+ gdbarch *gdbarch);
};
/* If true, query if PREC cannot record memory
@@ -669,7 +701,10 @@ record_full_arch_list_add_reg (struct regcache *regcache, int regnum)
regcache->cooked_read (regnum, rec.get_loc ());
- record_full_arch_list_add (rec);
+ if (regnum == gdbarch_pc_regnum (regcache->arch ()))
+ record_full_incomplete_instruction.pc = rec.reg ();
+ else
+ record_full_arch_list_add (rec);
return 0;
}
@@ -826,6 +861,7 @@ static enum target_stop_reason record_full_stop_reason
void record_full_instruction::exec_insn (regcache *regcache)
{
+ pc.execute (regcache);
for (auto &entry : effects)
if (entry.execute (regcache))
record_full_stop_reason = TARGET_STOPPED_BY_WATCHPOINT;
@@ -2181,68 +2217,86 @@ netorder32 (uint32_t input)
return ret;
}
-static void
-record_full_read_entry_from_bfd (bfd *cbfd, asection *osec, int *bfd_offset)
+record_full_reg_entry
+record_full_reg_entry::from_bfd (bfd *cbfd, asection *osec, int *bfd_offset)
{
- uint8_t rectype;
- uint32_t regnum, len;
- uint64_t addr;
+ uint32_t regnum;
regcache *cache = get_thread_regcache (inferior_thread ());
+ /* Get register number to regnum. */
+ bfdcore_read (cbfd, osec, ®num, sizeof (regnum),
+ bfd_offset);
+ regnum = netorder32 (regnum);
+
+ record_full_reg_entry reg (cache->arch (), regnum);
+
+ /* Get val. */
+ bfdcore_read (cbfd, osec, reg.get_loc (),
+ reg.len, bfd_offset);
+
+ if (record_debug)
+ gdb_printf (gdb_stdlog,
+ " Reading register %d (1 "
+ "plus %lu plus %d bytes)\n",
+ reg.num,
+ (unsigned long) sizeof (regnum),
+ reg.len);
+ return reg;
+
+}
+
+record_full_mem_entry
+record_full_mem_entry::from_bfd (bfd *cbfd, asection *osec, int *bfd_offset)
+{
+ uint32_t len;
+ uint64_t addr;
+
+ /* Get len. */
+ bfdcore_read (cbfd, osec, &len, sizeof (len), bfd_offset);
+ len = netorder32 (len);
+
+ /* Get addr. */
+ bfdcore_read (cbfd, osec, &addr, sizeof (addr),
+ bfd_offset);
+ addr = netorder64 (addr);
+
+ record_full_mem_entry mem (addr, len);
+
+ /* Get val. */
+ bfdcore_read (cbfd, osec, mem.get_loc (),
+ len, bfd_offset);
+
+ if (record_debug)
+ gdb_printf (gdb_stdlog,
+ " Reading memory %s (1 plus "
+ "%lu plus %lu plus %d bytes)\n",
+ paddress (get_current_arch (),
+ mem.addr),
+ (unsigned long) sizeof (addr),
+ (unsigned long) sizeof (len),
+ len);
+
+ return mem;
+}
+
+void
+record_full_entry::from_bfd (bfd *cbfd, asection *osec, int *bfd_offset)
+{
+ uint8_t rectype;
+ record_full_entry rec;
+
bfdcore_read (cbfd, osec, &rectype, sizeof (rectype), bfd_offset);
switch (rectype)
{
case record_full_reg: /* reg */
{
- /* Get register number to regnum. */
- bfdcore_read (cbfd, osec, ®num, sizeof (regnum), bfd_offset);
- regnum = netorder32 (regnum);
-
- record_full_entry rec (record_full_reg, cache->arch (), regnum);
-
- /* Get val. */
- bfdcore_read (cbfd, osec, rec.get_loc (),
- rec.reg ().len, bfd_offset);
-
- if (record_debug)
- gdb_printf (gdb_stdlog,
- " Reading register %d (1 "
- "plus %lu plus %d bytes)\n",
- rec.reg ().num,
- (unsigned long) sizeof (regnum),
- rec.reg ().len);
-
- record_full_arch_list_add (rec);
+ rec.entry = record_full_reg_entry::from_bfd (cbfd, osec, bfd_offset);
break;
}
case record_full_mem: /* mem */
{
- /* Get len. */
- bfdcore_read (cbfd, osec, &len, sizeof (len), bfd_offset);
- len = netorder32 (len);
-
- /* Get addr. */
- bfdcore_read (cbfd, osec, &addr, sizeof (addr),
- bfd_offset);
- addr = netorder64 (addr);
-
- record_full_entry rec (record_full_mem, addr, len);
-
- /* Get val. */
- bfdcore_read (cbfd, osec, rec.get_loc (), len, bfd_offset);
-
- if (record_debug)
- gdb_printf (gdb_stdlog,
- " Reading memory %s (1 plus "
- "%lu plus %lu plus %d bytes)\n",
- paddress (get_current_arch (),
- rec.mem ().addr),
- (unsigned long) sizeof (addr),
- (unsigned long) sizeof (len),
- len);
-
- record_full_arch_list_add (rec);
+ rec.entry = record_full_mem_entry::from_bfd (cbfd, osec, bfd_offset);
break;
}
@@ -2253,6 +2307,39 @@ record_full_read_entry_from_bfd (bfd *cbfd, asection *osec, int *bfd_offset)
bfd_get_filename (cbfd)));
break;
}
+ record_full_arch_list_add (rec);
+}
+
+void
+record_full_instruction::from_bfd (bfd *cbfd, asection *osec, int *bfd_offset)
+{
+ uint32_t eff_count = 0;
+ uint8_t sigval;
+ uint32_t insn_num;
+
+ /* First read the generic information for an instruction. */
+ bfdcore_read (cbfd, osec, &sigval, sizeof (uint8_t), bfd_offset);
+ bfdcore_read (cbfd, osec, &eff_count, sizeof (uint32_t),
+ bfd_offset);
+ bfdcore_read (cbfd, osec, &insn_num, sizeof (uint32_t),
+ bfd_offset);
+
+ record_full_incomplete_instruction.insn_num = netorder32 (insn_num);
+ if (sigval != GDB_SIGNAL_0)
+ record_full_incomplete_instruction.sigval = (gdb_signal) sigval;
+
+ record_full_incomplete_instruction.pc
+ = record_full_reg_entry::from_bfd (cbfd, osec, bfd_offset);
+
+ eff_count = netorder32 (eff_count);
+
+ /* This deals with all the side effects. */
+ while (eff_count > 0)
+ {
+ eff_count--;
+
+ record_full_entry::from_bfd (cbfd, osec, bfd_offset);
+ }
}
/* Restore the execution log from core file CBFD. */
@@ -2299,30 +2386,8 @@ record_full_restore (struct bfd &cbfd)
while (bfd_offset < osec_size)
{
record_full_reset_incomplete ();
- uint32_t eff_count = 0;
- uint8_t sigval;
- uint32_t insn_num;
- /* First read the generic information for an instruction. */
- bfdcore_read (&cbfd, osec, &sigval, sizeof (uint8_t), &bfd_offset);
- bfdcore_read (&cbfd, osec, &eff_count, sizeof (uint32_t),
- &bfd_offset);
- bfdcore_read (&cbfd, osec, &insn_num, sizeof (uint32_t),
- &bfd_offset);
-
- record_full_incomplete_instruction.insn_num = netorder32 (insn_num);
- if (sigval != GDB_SIGNAL_0)
- record_full_incomplete_instruction.sigval = (gdb_signal) sigval;
-
- eff_count = netorder32 (eff_count);
-
- /* This deals with all the side effects. */
- while (eff_count > 0)
- {
- eff_count--;
-
- record_full_read_entry_from_bfd (&cbfd, osec, &bfd_offset);
- }
+ record_full_instruction::from_bfd (&cbfd, osec, &bfd_offset);
record_full_save_instruction ();
}
@@ -2378,71 +2443,109 @@ cmd_record_full_restore (const char *args, int from_tty)
record_full_open (nullptr, from_tty);
}
-static void
-record_full_write_entry_to_bfd (record_full_entry &entry,
- gdb_bfd_ref_ptr obfd,
- asection *osec, int *bfd_offset,
- struct gdbarch *gdbarch)
+void
+record_full_reg_entry::to_bfd (gdb_bfd_ref_ptr obfd,
+ asection *osec, int *bfd_offset,
+ gdbarch *gdbarch)
+{
+ uint32_t regnum;
+
+ if (record_debug)
+ gdb_printf (gdb_stdlog,
+ " Writing register %d (1 "
+ "plus %lu plus %d bytes)\n",
+ this->num,
+ (unsigned long) sizeof (regnum),
+ this->len);
+
+ /* Write regnum. */
+ regnum = netorder32 (this->num);
+ bfdcore_write (obfd.get (), osec, ®num, sizeof (regnum), bfd_offset);
+
+ /* Write regval. */
+ bfdcore_write (obfd.get (), osec, this->get_loc (), this->len, bfd_offset);
+}
+
+void
+record_full_mem_entry::to_bfd (gdb_bfd_ref_ptr obfd,
+ asection *osec, int *bfd_offset,
+ gdbarch *gdbarch)
+{
+ uint32_t len;
+ uint64_t addr;
+
+ if (record_debug)
+ gdb_printf (gdb_stdlog,
+ " Writing memory %s (1 plus "
+ "%lu plus %lu plus %d bytes)\n",
+ paddress (gdbarch, this->addr),
+ (unsigned long) sizeof (addr),
+ (unsigned long) sizeof (len),
+ this->len);
+
+ /* Write memlen. */
+ len = netorder32 (this->len);
+ bfdcore_write (obfd.get (), osec, &len, sizeof (len), bfd_offset);
+
+ /* Write memaddr. */
+ addr = netorder64 (this->addr);
+ bfdcore_write (obfd.get (), osec, &addr, sizeof (addr), bfd_offset);
+
+ /* Write memval. */
+ bfdcore_write (obfd.get (), osec, this->get_loc (), this->len, bfd_offset);
+}
+
+void
+record_full_entry::to_bfd (gdb_bfd_ref_ptr obfd, asection *osec,
+ int *bfd_offset, gdbarch *gdbarch)
{
/* Save entry. */
uint8_t type;
- uint32_t regnum, len;
- uint64_t addr;
- type = entry.type ();
+ type = this->type ();
bfdcore_write (obfd.get (), osec, &type, sizeof (type), bfd_offset);
switch (type)
{
case record_full_reg: /* reg */
- {
- auto reg = entry.reg ();
- if (record_debug)
- gdb_printf (gdb_stdlog,
- " Writing register %d (1 "
- "plus %lu plus %d bytes)\n",
- reg.num,
- (unsigned long) sizeof (regnum),
- reg.len);
-
- /* Write regnum. */
- regnum = netorder32 (reg.num);
- bfdcore_write (obfd.get (), osec, ®num, sizeof (regnum), bfd_offset);
-
- /* Write regval. */
- bfdcore_write (obfd.get (), osec, entry.get_loc (), reg.len, bfd_offset);
- break;
- }
+ reg ().to_bfd (obfd, osec, bfd_offset, gdbarch);
+ break;
case record_full_mem: /* mem */
- {
- auto mem = entry.mem ();
- if (record_debug)
- gdb_printf (gdb_stdlog,
- " Writing memory %s (1 plus "
- "%lu plus %lu plus %d bytes)\n",
- paddress (gdbarch, mem.addr),
- (unsigned long) sizeof (addr),
- (unsigned long) sizeof (len),
- mem.len);
-
- /* Write memlen. */
- len = netorder32 (mem.len);
- bfdcore_write (obfd.get (), osec, &len, sizeof (len), bfd_offset);
-
- /* Write memaddr. */
- addr = netorder64 (mem.addr);
- bfdcore_write (obfd.get (), osec, &addr, sizeof (addr), bfd_offset);
-
- /* Write memval. */
- bfdcore_write (obfd.get (), osec, entry.get_loc (), mem.len,
- bfd_offset);
- break;
- }
+ mem ().to_bfd (obfd, osec, bfd_offset, gdbarch);
+ break;
}
}
+void
+record_full_instruction::to_bfd (gdb_bfd_ref_ptr obfd, asection *osec,
+ int *bfd_offset, gdbarch *gdbarch)
+{
+ uint32_t eff_count = (uint32_t) this->effects.size ();
+ uint32_t insn_num = this->insn_num;
+ uint8_t sigval = (this->sigval.has_value ())
+ ? this->sigval.value ()
+ : GDB_SIGNAL_0;
+
+ /* Signal. */
+ bfdcore_write (obfd.get (), osec, &sigval, sizeof (sigval), bfd_offset);
+ eff_count = netorder32 (eff_count);
+ /* Number of effects. */
+ bfdcore_write (obfd.get (), osec, &eff_count, sizeof (eff_count),
+ bfd_offset);
+ /* Instruction number. */
+ bfdcore_write (obfd.get (), osec, &insn_num, sizeof (uint32_t),
+ bfd_offset);
+
+ this->pc.to_bfd (obfd, osec, bfd_offset, gdbarch);
+
+ for (auto &entry : this->effects)
+ {
+ entry.to_bfd (obfd, osec, bfd_offset, gdbarch);
+ }
+}
+
/* Save the execution log to a file. We use a modified elf corefile
format, with an extra section for our data. */
@@ -2484,6 +2587,7 @@ record_full_base_target::save_record (const char *recfilename)
{
/* Number of effects of an instruction. */
save_size += sizeof (uint32_t) + sizeof (uint8_t) + sizeof (uint32_t);
+ save_size += 4 + record_full_list[i].pc.len;
for (auto &entry : record_full_list[i].effects)
switch (entry.type ())
{
@@ -2525,27 +2629,7 @@ record_full_base_target::save_record (const char *recfilename)
record list. */
for (int i = 0; i < record_full_list.size (); i++)
{
- uint32_t eff_count = (uint32_t) record_full_list[i].effects.size ();
- uint32_t insn_num = record_full_list[i].insn_num;
- uint8_t sigval = (record_full_list[i].sigval.has_value ())
- ? record_full_list[i].sigval.value ()
- : GDB_SIGNAL_0;
-
- /* Signal. */
- bfdcore_write (obfd.get (), osec, &sigval, sizeof (sigval), &bfd_offset);
- eff_count = netorder32 (eff_count);
- /* Number of effects. */
- bfdcore_write (obfd.get (), osec, &eff_count, sizeof (eff_count),
- &bfd_offset);
- /* Instruction number. */
- bfdcore_write (obfd.get (), osec, &insn_num, sizeof (uint32_t),
- &bfd_offset);
-
- for (auto &entry : record_full_list[i].effects)
- {
- record_full_write_entry_to_bfd (entry, obfd, osec, &bfd_offset,
- gdbarch);
- }
+ record_full_list[i].to_bfd (obfd, osec, &bfd_offset, gdbarch);
/* Execute entry. */
if (i < record_full_next_insn)
record_full_list[i].exec_insn (regcache);
@@ -2622,6 +2706,9 @@ maintenance_print_record_instruction (const char *args, int from_tty)
auto to_print = record_full_list.begin () + offset;
gdbarch *arch = current_inferior ()->arch ();
+ struct value_print_options opts;
+ get_user_print_options (&opts);
+ opts.raw = true;
for (auto entry : to_print->effects)
{
@@ -2635,9 +2722,6 @@ maintenance_print_record_instruction (const char *args, int from_tty)
entry.get_loc ());
gdb_printf ("Register %s changed: ",
gdbarch_register_name (arch, entry.reg ().num));
- struct value_print_options opts;
- get_user_print_options (&opts);
- opts.raw = true;
value_print (val, gdb_stdout, &opts);
gdb_printf ("\n");
break;
@@ -2656,6 +2740,12 @@ maintenance_print_record_instruction (const char *args, int from_tty)
}
}
}
+ type *regtype = gdbarch_register_type (arch, to_print->pc.num);
+ value *val = value_from_contents (regtype, to_print->pc.get_loc ());
+ gdb_printf ("Register %s changed: ",
+ gdbarch_register_name (arch, to_print->pc.num));
+ value_print (val, gdb_stdout, &opts);
+ gdb_printf ("\n");
}
INIT_GDB_FILE (record_full)
--
2.53.0
^ permalink raw reply [flat|nested] 19+ messages in thread
* [PATCH v2 6/6] gdb/record: Define new version of the record-save section
2026-04-23 15:25 [PATCH v2 0/6] refactor the internals of record-full Guinevere Larsen
` (4 preceding siblings ...)
2026-04-23 15:26 ` [PATCH v2 5/6] gdb/record: extract the PC to record_full_instruction Guinevere Larsen
@ 2026-04-23 15:26 ` Guinevere Larsen
2026-04-23 15:45 ` Eli Zaretskii
5 siblings, 1 reply; 19+ messages in thread
From: Guinevere Larsen @ 2026-04-23 15:26 UTC (permalink / raw)
To: gdb-patches; +Cc: Guinevere Larsen, Thiago Jung Bauermann
With the changes to the internal representation of the history, we can
no longer support the previous record save format. This commit makes it
official, documenting the new format and changing the magic number.
Reviewed-by: Thiago Jung Bauermann <thiago.bauermann@linaro.org>
---
gdb/NEWS | 4 ++++
gdb/record-full.c | 35 +++++++++++++++++++++++++++++++----
2 files changed, 35 insertions(+), 4 deletions(-)
diff --git a/gdb/NEWS b/gdb/NEWS
index 4cf91053c95..1dfd8c8e6ca 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -42,6 +42,10 @@
* Support for the binary file format dbx has been removed.
+* The format for a saved execution record, created when the command
+ 'record save' is used, has been updated, and previous formats are
+ no longer supported.
+
* When connected to an extended-remote target GDB can now
automatically set the 'remote exec-file' in some cases. GDB will
auto set the remote exec-file only if the remote wasn't started with
diff --git a/gdb/record-full.c b/gdb/record-full.c
index 05d515f5295..8970774a0c5 100644
--- a/gdb/record-full.c
+++ b/gdb/record-full.c
@@ -76,7 +76,8 @@
( (record_full_next_insn != record_full_list.size ()) \
|| ::execution_direction == EXEC_REVERSE)
-#define RECORD_FULL_FILE_MAGIC netorder32(0x20091016)
+#define RECORD_FULL_FILE_MAGIC_OLD netorder32(0x20091016)
+#define RECORD_FULL_FILE_MAGIC netorder32(0x20260415)
/* These are the core structs of the process record functionality.
@@ -2179,6 +2180,27 @@ record_full_core_target::has_execution (inferior *inf)
8 bytes: memory address (network byte order).
n bytes: memory value (n == memory length).
+ Version 3 (all numbers are in network order).
+ 4 bytes: Magic number (0x20260415).
+ NOTE: be sure to change whenever this file format changes!
+
+ Records:
+ record_full_instruction:
+ 1 byte: signal.
+ 4 bytes: number of reg and mem entries for this instruction.
+ 4 bytes: instruction sequence number.
+ 4 bytes: PC register ID.
+ N bytes: PC address of instruction (N == size of PC).
+ Effects:
+ record_full_reg:
+ 1 byte: record_type (record_full_reg, see enum record_full_type).
+ 4 bytes: Register ID.
+ n bytes: register value (n == actual register size).
+ record_full_mem:
+ 1 byte: record_type (record_full_mem, see enum record_full_type).
+ 4 bytes: memory length.
+ 8 bytes: memory address.
+ n bytes: memory value (n = memory length).
*/
/* bfdcore_read -- read bytes from a core file section. */
@@ -2372,9 +2394,14 @@ record_full_restore (struct bfd &cbfd)
/* Check the magic code. */
bfdcore_read (&cbfd, osec, &magic, sizeof (magic), &bfd_offset);
if (magic != RECORD_FULL_FILE_MAGIC)
- error (_("Version mismatch or file format error in core file %ps."),
- styled_string (file_name_style.style (),
- bfd_get_filename (&cbfd)));
+ {
+ if (magic == RECORD_FULL_FILE_MAGIC_OLD)
+ error (_("This old recording format is no longer supported."));
+ else
+ error (_("Version mismatch or file format error in core file %ps."),
+ styled_string (file_name_style.style (),
+ bfd_get_filename (&cbfd)));
+ }
if (record_debug)
gdb_printf (gdb_stdlog,
" Reading 4-byte magic cookie "
--
2.53.0
^ permalink raw reply [flat|nested] 19+ messages in thread
* Re: [PATCH v2 6/6] gdb/record: Define new version of the record-save section
2026-04-23 15:26 ` [PATCH v2 6/6] gdb/record: Define new version of the record-save section Guinevere Larsen
@ 2026-04-23 15:45 ` Eli Zaretskii
0 siblings, 0 replies; 19+ messages in thread
From: Eli Zaretskii @ 2026-04-23 15:45 UTC (permalink / raw)
To: Guinevere Larsen; +Cc: gdb-patches, thiago.bauermann
> From: Guinevere Larsen <guinevere@redhat.com>
> Cc: Guinevere Larsen <guinevere@redhat.com>,
> Thiago Jung Bauermann <thiago.bauermann@linaro.org>
> Date: Thu, 23 Apr 2026 12:26:04 -0300
>
> With the changes to the internal representation of the history, we can
> no longer support the previous record save format. This commit makes it
> official, documenting the new format and changing the magic number.
>
> Reviewed-by: Thiago Jung Bauermann <thiago.bauermann@linaro.org>
> ---
> gdb/NEWS | 4 ++++
> gdb/record-full.c | 35 +++++++++++++++++++++++++++++++----
> 2 files changed, 35 insertions(+), 4 deletions(-)
Thanks, the NEWS part is okay.
Reviewed-By: Eli Zaretskii <eliz@gnu.org>
^ permalink raw reply [flat|nested] 19+ messages in thread
* Re: [PATCH v2 1/6] gdb/record: Refactor record history
2026-04-23 15:25 ` [PATCH v2 1/6] gdb/record: Refactor record history Guinevere Larsen
@ 2026-04-28 3:28 ` Thiago Jung Bauermann
2026-04-28 19:54 ` Guinevere Larsen
2026-05-06 21:16 ` Schimpe, Christina
1 sibling, 1 reply; 19+ messages in thread
From: Thiago Jung Bauermann @ 2026-04-28 3:28 UTC (permalink / raw)
To: Guinevere Larsen; +Cc: gdb-patches
Hello Guinevere,
Thanks! It all looks good to me now.
Guinevere Larsen <guinevere@redhat.com> writes:
> This is the first step in a large refactor in how GDB keeps execution
> history. Rather than using a linked list where multiple entries can
> describe a single instruction, the history will now be stored in an
> std::deque, each instruction being one entry in the deque.
>
> The choice was initially to use an std::vector, but it would become
> unwieldy because it needs all the memory to be consecutive, which is
> hard for 200 thousand entries. Deque was picked because it was a nice
> midpoint between vector (maximum cache cohesion) and linked list
> (maximum ease of finding space to store more).
>
> Each instruction in memory will be now one record_full_instruction
> entry, which for this commit just contains a vector of
> record_full_entry for the effects of the instruction, and the data that
> was stored in the record_full_end entry (that is, the instruction number
> and the signal, if any).
>
> This change introduced a minimal performance improvement (what's
> important is that it isn't a degradation) and a reduction in the total
> memory footprint of roughly 20% if the entire history is used.
> ---
> gdb/aarch64-tdep.c | 2 -
> gdb/amd64-linux-tdep.c | 3 -
> gdb/arm-tdep.c | 2 -
> gdb/i386-linux-tdep.c | 3 -
> gdb/i386-tdep.c | 4 -
> gdb/loongarch-tdep.c | 2 -
> gdb/moxie-tdep.c | 2 -
> gdb/ppc-linux-tdep.c | 3 -
> gdb/record-full.c | 1180 ++++++++++++++++------------------------
> gdb/record-full.h | 1 -
> gdb/riscv-tdep.c | 3 -
> gdb/rs6000-tdep.c | 4 -
> gdb/s390-linux-tdep.c | 3 -
> gdb/s390-tdep.c | 2 -
> 14 files changed, 476 insertions(+), 738 deletions(-)
Reviewed-by: Thiago Jung Bauermann <thiago.bauermann@linaro.org>
--
Thiago
^ permalink raw reply [flat|nested] 19+ messages in thread
* Re: [PATCH v2 3/6] gdb/record: c++ify internal structures of record-full.c
2026-04-23 15:26 ` [PATCH v2 3/6] gdb/record: c++ify internal structures of record-full.c Guinevere Larsen
@ 2026-04-28 3:29 ` Thiago Jung Bauermann
0 siblings, 0 replies; 19+ messages in thread
From: Thiago Jung Bauermann @ 2026-04-28 3:29 UTC (permalink / raw)
To: Guinevere Larsen; +Cc: gdb-patches
Guinevere Larsen <guinevere@redhat.com> writes:
> This commit adds a constructor, destructor, and some methods to the
> structures record_full_entry, record_full_reg_entry and
> record_full_mem_entry. This is a move to disentangle the internal
> representation of the data and how record-full manipulates it for
> replaying.
>
> Along with this change, record_full_entry is changed to use an
> std::variant, since it was basically doing that already, but now we have
> the stdlibc++ error checking to make sure we're only accessing elements
> we're allowed to.
> ---
> gdb/record-full.c | 553 ++++++++++++++++++++++++----------------------
> 1 file changed, 289 insertions(+), 264 deletions(-)
Reviewed-by: Thiago Jung Bauermann <thiago.bauermann@linaro.org>
--
Thiago
^ permalink raw reply [flat|nested] 19+ messages in thread
* Re: [PATCH v2 4/6] gdb/record: make record_full_history more c++-like
2026-04-23 15:26 ` [PATCH v2 4/6] gdb/record: make record_full_history more c++-like Guinevere Larsen
@ 2026-04-28 3:29 ` Thiago Jung Bauermann
0 siblings, 0 replies; 19+ messages in thread
From: Thiago Jung Bauermann @ 2026-04-28 3:29 UTC (permalink / raw)
To: Guinevere Larsen; +Cc: gdb-patches
Guinevere Larsen <guinevere@redhat.com> writes:
> Move some functions to being a method of record_full_history, instead of
> floating functions.
> ---
> gdb/record-full.c | 25 +++++++++++--------------
> 1 file changed, 11 insertions(+), 14 deletions(-)
Reviewed-by: Thiago Jung Bauermann <thiago.bauermann@linaro.org>
--
Thiago
^ permalink raw reply [flat|nested] 19+ messages in thread
* Re: [PATCH v2 5/6] gdb/record: extract the PC to record_full_instruction
2026-04-23 15:26 ` [PATCH v2 5/6] gdb/record: extract the PC to record_full_instruction Guinevere Larsen
@ 2026-04-28 3:30 ` Thiago Jung Bauermann
0 siblings, 0 replies; 19+ messages in thread
From: Thiago Jung Bauermann @ 2026-04-28 3:30 UTC (permalink / raw)
To: Guinevere Larsen; +Cc: gdb-patches
Guinevere Larsen <guinevere@redhat.com> writes:
> This commit makes it so the PC is not saved as part of the
> record_full_instruction effects, but rather gets a special location.
> That is because a couple of commands would really benefit from it being
> easy to find the PC (especially ones from record-btrace that's haven't
> been implemented to record-full yet, such as the ones in PR
> record/18059), while also possibly allowing for one fewer resizing of
> the effect vector (and saving an entire byte in the process).
>
> This commit also refactored record_full_read_entry_from_bfd and
> record_full_write_entry_to_bfd, to make them methods of
> record_full_reg_entry and record_full_mem_entry, and also creates
> similar methods for record_full_entry and record_full_instruction.
> These could be turned into constructors in a future step of
> c++ification, but it felt like too much change for a single commit.
> ---
> gdb/record-full.c | 384 ++++++++++++++++++++++++++++------------------
> 1 file changed, 237 insertions(+), 147 deletions(-)
Reviewed-by: Thiago Jung Bauermann <thiago.bauermann@linaro.org>
--
Thiago
^ permalink raw reply [flat|nested] 19+ messages in thread
* Re: [PATCH v2 1/6] gdb/record: Refactor record history
2026-04-28 3:28 ` Thiago Jung Bauermann
@ 2026-04-28 19:54 ` Guinevere Larsen
0 siblings, 0 replies; 19+ messages in thread
From: Guinevere Larsen @ 2026-04-28 19:54 UTC (permalink / raw)
To: Thiago Jung Bauermann; +Cc: gdb-patches
On 4/28/26 12:28 AM, Thiago Jung Bauermann wrote:
> Hello Guinevere,
>
> Thanks! It all looks good to me now.
>
> Guinevere Larsen <guinevere@redhat.com> writes:
>
>> This is the first step in a large refactor in how GDB keeps execution
>> history. Rather than using a linked list where multiple entries can
>> describe a single instruction, the history will now be stored in an
>> std::deque, each instruction being one entry in the deque.
>>
>> The choice was initially to use an std::vector, but it would become
>> unwieldy because it needs all the memory to be consecutive, which is
>> hard for 200 thousand entries. Deque was picked because it was a nice
>> midpoint between vector (maximum cache cohesion) and linked list
>> (maximum ease of finding space to store more).
>>
>> Each instruction in memory will be now one record_full_instruction
>> entry, which for this commit just contains a vector of
>> record_full_entry for the effects of the instruction, and the data that
>> was stored in the record_full_end entry (that is, the instruction number
>> and the signal, if any).
>>
>> This change introduced a minimal performance improvement (what's
>> important is that it isn't a degradation) and a reduction in the total
>> memory footprint of roughly 20% if the entire history is used.
>> ---
>> gdb/aarch64-tdep.c | 2 -
>> gdb/amd64-linux-tdep.c | 3 -
>> gdb/arm-tdep.c | 2 -
>> gdb/i386-linux-tdep.c | 3 -
>> gdb/i386-tdep.c | 4 -
>> gdb/loongarch-tdep.c | 2 -
>> gdb/moxie-tdep.c | 2 -
>> gdb/ppc-linux-tdep.c | 3 -
>> gdb/record-full.c | 1180 ++++++++++++++++------------------------
>> gdb/record-full.h | 1 -
>> gdb/riscv-tdep.c | 3 -
>> gdb/rs6000-tdep.c | 4 -
>> gdb/s390-linux-tdep.c | 3 -
>> gdb/s390-tdep.c | 2 -
>> 14 files changed, 476 insertions(+), 738 deletions(-)
> Reviewed-by: Thiago Jung Bauermann <thiago.bauermann@linaro.org>
>
Thanks for all the reviews! I applied your review tag to all the
patches, but I will wait until next thursday, so that anyone has time to
give thoughts before I self-approve the patch series.
--
Cheers,
Guinevere Larsen
It/she
^ permalink raw reply [flat|nested] 19+ messages in thread
* RE: [PATCH v2 1/6] gdb/record: Refactor record history
2026-04-23 15:25 ` [PATCH v2 1/6] gdb/record: Refactor record history Guinevere Larsen
2026-04-28 3:28 ` Thiago Jung Bauermann
@ 2026-05-06 21:16 ` Schimpe, Christina
2026-05-07 17:38 ` Guinevere Larsen
1 sibling, 1 reply; 19+ messages in thread
From: Schimpe, Christina @ 2026-05-06 21:16 UTC (permalink / raw)
To: Guinevere Larsen, gdb-patches
Hi Guinevere,
Thank you for working on this.
I found two items that might be worth looking at in more detail, but
apart from that it’s mostly minor nits. Please find my feedback below.
I don’t have much experience with the record feature, so my review is
a bit slow here. To fully understand this patch, I probably need more time,
but I wanted to share the comments I already have. Sorry for chiming in
so late. I’ll try again tomorrow, or by Friday at the latest.
> -----Original Message-----
> From: Guinevere Larsen <guinevere@redhat.com>
> Sent: Donnerstag, 23. April 2026 17:26
> To: gdb-patches@sourceware.org
> Cc: Guinevere Larsen <guinevere@redhat.com>
> Subject: [PATCH v2 1/6] gdb/record: Refactor record history
>
> This is the first step in a large refactor in how GDB keeps execution
> history. Rather than using a linked list where multiple entries can
> describe a single instruction, the history will now be stored in an
> std::deque, each instruction being one entry in the deque.
>
> The choice was initially to use an std::vector, but it would become
> unwieldy because it needs all the memory to be consecutive, which is
> hard for 200 thousand entries. Deque was picked because it was a nice
> midpoint between vector (maximum cache cohesion) and linked list
> (maximum ease of finding space to store more).
>
> Each instruction in memory will be now one record_full_instruction
> entry, which for this commit just contains a vector of
> record_full_entry for the effects of the instruction, and the data that
> was stored in the record_full_end entry (that is, the instruction number
> and the signal, if any).
>
> This change introduced a minimal performance improvement (what's
> important is that it isn't a degradation) and a reduction in the total
> memory footprint of roughly 20% if the entire history is used.
> ---
> gdb/aarch64-tdep.c | 2 -
> gdb/amd64-linux-tdep.c | 3 -
> gdb/arm-tdep.c | 2 -
> gdb/i386-linux-tdep.c | 3 -
> gdb/i386-tdep.c | 4 -
> gdb/loongarch-tdep.c | 2 -
> gdb/moxie-tdep.c | 2 -
> gdb/ppc-linux-tdep.c | 3 -
> gdb/record-full.c | 1180 ++++++++++++++++------------------------
> gdb/record-full.h | 1 -
> gdb/riscv-tdep.c | 3 -
> gdb/rs6000-tdep.c | 4 -
> gdb/s390-linux-tdep.c | 3 -
> gdb/s390-tdep.c | 2 -
> 14 files changed, 476 insertions(+), 738 deletions(-)
>
> diff --git a/gdb/aarch64-tdep.c b/gdb/aarch64-tdep.c
> index 4befaa2720d..a532992b1d8 100644
> --- a/gdb/aarch64-tdep.c
> +++ b/gdb/aarch64-tdep.c
> @@ -6210,8 +6210,6 @@ aarch64_process_record (struct gdbarch *gdbarch,
> struct regcache *regcache,
> aarch64_record.aarch64_mems[rec_no].len))
> ret = -1;
>
> - if (record_full_arch_list_add_end ())
> - ret = -1;
> }
>
> deallocate_reg_mem (&aarch64_record);
> diff --git a/gdb/amd64-linux-tdep.c b/gdb/amd64-linux-tdep.c
> index a5ac26654cf..9b23db72bbe 100644
> --- a/gdb/amd64-linux-tdep.c
> +++ b/gdb/amd64-linux-tdep.c
> @@ -1591,9 +1591,6 @@ amd64_linux_record_signal (struct gdbarch
> *gdbarch,
> + AMD64_LINUX_frame_size))
> return -1;
>
> - if (record_full_arch_list_add_end ())
> - return -1;
> -
> return 0;
> }
>
> diff --git a/gdb/arm-tdep.c b/gdb/arm-tdep.c
> index 08cce9dbad8..1ce0927f26b 100644
> --- a/gdb/arm-tdep.c
> +++ b/gdb/arm-tdep.c
> @@ -14911,8 +14911,6 @@ arm_process_record (struct gdbarch *gdbarch,
> struct regcache *regcache,
> }
> }
>
> - if (record_full_arch_list_add_end ())
> - ret = -1;
> }
>
>
> diff --git a/gdb/i386-linux-tdep.c b/gdb/i386-linux-tdep.c
> index 23aeccac9fc..4f33766fcdd 100644
> --- a/gdb/i386-linux-tdep.c
> +++ b/gdb/i386-linux-tdep.c
> @@ -949,9 +949,6 @@ i386_linux_record_signal (struct gdbarch *gdbarch,
> I386_LINUX_xstate +
> I386_LINUX_frame_size))
> return -1;
>
> - if (record_full_arch_list_add_end ())
> - return -1;
> -
> return 0;
> }
>
>
> diff --git a/gdb/i386-tdep.c b/gdb/i386-tdep.c
> index fa935b5fcdb..fee36b46a73 100644
> --- a/gdb/i386-tdep.c
> +++ b/gdb/i386-tdep.c
> @@ -5201,8 +5201,6 @@ i386_record_vex (struct i386_record_s *ir, uint8_t
> vex_w, uint8_t vex_r,
> }
>
> record_full_arch_list_add_reg (ir->regcache, ir-
> >regmap[X86_RECORD_REIP_REGNUM]);
> - if (record_full_arch_list_add_end ())
> - return -1;
>
> return 0;
> }
> @@ -8359,8 +8357,6 @@ Do you want to stop the program?"),
>
> /* In the future, maybe still need to deal with need_dasm. */
> I386_RECORD_FULL_ARCH_LIST_ADD_REG (X86_RECORD_REIP_REGNUM);
> - if (record_full_arch_list_add_end ())
> - return -1;
>
> return 0;
>
> diff --git a/gdb/loongarch-tdep.c b/gdb/loongarch-tdep.c
> index 225b1abb703..5ec6b2a48d0 100644
> --- a/gdb/loongarch-tdep.c
> +++ b/gdb/loongarch-tdep.c
> @@ -2789,8 +2789,6 @@ loongarch_process_record (struct gdbarch
> *gdbarch, struct regcache *regcache,
> LOONGARCH_PC_REGNUM))
> return -1;
>
> - if (record_full_arch_list_add_end ())
> - return -1;
> }
>
> return ret;
> diff --git a/gdb/moxie-tdep.c b/gdb/moxie-tdep.c
> index c8a04d21f59..2f8f0186488 100644
> --- a/gdb/moxie-tdep.c
> +++ b/gdb/moxie-tdep.c
> @@ -1040,8 +1040,6 @@ moxie_process_record (struct gdbarch *gdbarch,
> struct regcache *regcache,
>
> if (record_full_arch_list_add_reg (regcache, MOXIE_PC_REGNUM))
> return -1;
> - if (record_full_arch_list_add_end ())
> - return -1;
> return 0;
> }
>
> diff --git a/gdb/ppc-linux-tdep.c b/gdb/ppc-linux-tdep.c
> index 19698eaacbe..e2f53551709 100644
> --- a/gdb/ppc-linux-tdep.c
> +++ b/gdb/ppc-linux-tdep.c
> @@ -1565,9 +1565,6 @@ ppc_linux_record_signal (struct gdbarch *gdbarch,
> struct regcache *regcache,
> if (record_full_arch_list_add_mem (sp, SIGNAL_FRAMESIZE +
> sizeof_rt_sigframe))
> return -1;
>
> - if (record_full_arch_list_add_end ())
> - return -1;
> -
> return 0;
> }
>
> diff --git a/gdb/record-full.c b/gdb/record-full.c
> index 69d2c100e57..aac69cee17e 100644
> --- a/gdb/record-full.c
> +++ b/gdb/record-full.c
I think we should include vector, optional and deque directly.
> @@ -72,20 +72,17 @@
> #define DEFAULT_RECORD_FULL_INSN_MAX_NUM 200000
>
> #define RECORD_FULL_IS_REPLAY \
> - (record_full_list->next || ::execution_direction == EXEC_REVERSE)
> + ( (record_full_next_insn != record_full_list.size ()) \
Nit: No whitespace after the first bracket:
=> ((record_full_next_insn != record_full_list.size ()) \
> + || ::execution_direction == EXEC_REVERSE)
>
> #define RECORD_FULL_FILE_MAGIC netorder32(0x20091016)
>
> /* These are the core structs of the process record functionality.
>
> A record_full_entry is a record of the value change of a register
> - ("record_full_reg") or a part of memory ("record_full_mem"). And each
> - instruction must have a struct record_full_entry ("record_full_end")
> - that indicates that this is the last struct record_full_entry of this
> - instruction.
> -
> - Each struct record_full_entry is linked to "record_full_list" by "prev"
> - and "next" pointers. */
> + ("record_full_reg") or a part of memory ("record_full_mem").
> + These are saved on the record_full_instruction struct, which also
> + contains some extra information, such as delivered signals. */
>
> struct record_full_mem_entry
> {
> @@ -112,47 +109,14 @@ struct record_full_reg_entry
> } u;
> };
>
> -struct record_full_end_entry
> -{
> - enum gdb_signal sigval;
> - ULONGEST insn_num;
> -};
> -
> enum record_full_type
> {
> - record_full_end = 0,
> record_full_reg,
> record_full_mem
> };
>
> -/* This is the data structure that makes up the execution log.
> -
> - The execution log consists of a single linked list of entries
> - of type "struct record_full_entry". It is doubly linked so that it
> - can be traversed in either direction.
> -
> - The start of the list is anchored by a struct called
> - "record_full_first". The pointer "record_full_list" either points
> - to the last entry that was added to the list (in record mode), or to
> - the next entry in the list that will be executed (in replay mode).
> -
> - Each list element (struct record_full_entry), in addition to next
> - and prev pointers, consists of a union of three entry types: mem,
> - reg, and end. A field called "type" determines which entry type is
> - represented by a given list element.
> -
> - Each instruction that is added to the execution log is represented
> - by a variable number of list elements ('entries'). The instruction
> - will have one "reg" entry for each register that is changed by
> - executing the instruction (including the PC in every case). It
> - will also have one "mem" entry for each memory change. Finally,
> - each instruction will have an "end" entry that separates it from
> - the changes associated with the next instruction. */
> -
> struct record_full_entry
> {
> - struct record_full_entry *prev;
> - struct record_full_entry *next;
> enum record_full_type type;
> union
> {
> @@ -160,11 +124,31 @@ struct record_full_entry
> struct record_full_reg_entry reg;
> /* mem */
> struct record_full_mem_entry mem;
> - /* end */
> - struct record_full_end_entry end;
> } u;
> };
>
> +/* This is the main structure that comprises the execution log.
> + Each instruction is comprised of:
> + * The instruction number: How many instructions were recorded before
> + this one;
> + * sigval: Whether the inferior received a signal while the following
> + instruction was being recorded;
> + * effects: A list of record_full_entry structures, each of which
> + describing one effect that the instruction has on the inferior.
> +
> + Note, the signal is stored in the previous instruction for historical
> + reasons. This is how it was first implemented, and no one has gotten
> + around to changing it yet. */
> +
> +struct record_full_instruction
> +{
> + /* This might be different from the index if
> + we had to remove the first few instructions. */
> + uint32_t insn_num;
> + std::optional<gdb_signal> sigval;
> + std::vector<record_full_entry> effects;
> +};
> +
> /* If true, query if PREC cannot record memory
> change of next instruction. */
> bool record_full_memory_query = false;
> @@ -181,27 +165,25 @@ static detached_regcache
> *record_full_core_regbuf = NULL;
> static std::vector<target_section> record_full_core_sections;
> static struct record_full_core_buf_entry *record_full_core_buf_list = NULL;
>
> -/* The following variables are used for managing the linked list that
> - represents the execution log.
> +/* The following variables are used for managing the history of executed
> + instructions from the inferior.
>
> - record_full_first is the anchor that holds down the beginning of
> - the list.
> + record_full_list contains all instructions that were fully executed and
> + saved to the log, so that we can replay the execution.
>
> - record_full_list serves two functions:
> - 1) In record mode, it anchors the end of the list.
> - 2) In replay mode, it traverses the list and points to
> - the next instruction that must be emulated.
> + record_full_next_insn always points to the next instruction that would
> + be executed if the inferior executes forward. In the special case when
> + the inferior is not replaying, record_full_next_insn points past the
> + end of the history.
>
> - record_full_arch_list_head and record_full_arch_list_tail are used
> - to manage a separate list, which is used to build up the change
> - elements of the currently executing instruction during record mode.
> - When this instruction has been completely annotated in the "arch
> - list", it will be appended to the main execution log. */
> + record_full_incomplete_instruction holds a partial instruction, while
> + the lower target is disassembling the instruction, or as partial xfers are
> + happening. It is manipulated by the "arch list" functions for historical
> + reasons. */
>
> -static struct record_full_entry record_full_first;
> -static struct record_full_entry *record_full_list = &record_full_first;
> -static struct record_full_entry *record_full_arch_list_head = NULL;
> -static struct record_full_entry *record_full_arch_list_tail = NULL;
> +static std::deque<record_full_instruction> record_full_list;
Given that this is not a list anymore I wonder if we should better call this sth. like
record_full_history or record_full_log or even simply recorded_instructions?
> +static record_full_instruction record_full_incomplete_instruction;
> +int record_full_next_insn;
>
> /* true ask user. false auto delete the last struct record_full_entry. */
> static bool record_full_stop_at_limit = true;
> @@ -361,6 +343,14 @@ record_full_target::kill ()
> record_kill (this);
> }
>
> +static void
> +record_full_reset_incomplete ()
> +{
> + record_full_incomplete_instruction.effects.clear ();
> + record_full_incomplete_instruction.sigval.reset ();
> + record_full_incomplete_instruction.insn_num = 0;
> +}
> +
> /* See record-full.h. */
>
> int
> @@ -390,156 +380,120 @@ static struct cmd_list_element
> *show_record_full_cmdlist;
> /* Command list for "record full". */
> static struct cmd_list_element *record_full_cmdlist;
>
> -static void record_full_goto_insn (struct record_full_entry *entry,
> +static void record_full_goto_insn (size_t target_insn,
> enum exec_direction_kind dir);
>
> -/* Alloc and free functions for record_full_reg, record_full_mem, and
> - record_full_end entries. */
> +/* Initialization and cleanup functions for record_full_reg and
> + record_full_mem entries. */
>
> -/* Alloc a record_full_reg record entry. */
> +/* Init a record_full_reg record entry. */
>
> -static inline struct record_full_entry *
> -record_full_reg_alloc (struct regcache *regcache, int regnum)
> +static inline struct record_full_entry
> +record_full_reg_init (struct regcache *regcache, int regnum)
> {
> - struct record_full_entry *rec;
> + struct record_full_entry rec;
> struct gdbarch *gdbarch = regcache->arch ();
>
> - rec = XCNEW (struct record_full_entry);
> - rec->type = record_full_reg;
> - rec->u.reg.num = regnum;
> - rec->u.reg.len = register_size (gdbarch, regnum);
> - if (rec->u.reg.len > sizeof (rec->u.reg.u.buf))
> - rec->u.reg.u.ptr = (gdb_byte *) xmalloc (rec->u.reg.len);
> + rec.type = record_full_reg;
> + rec.u.reg.num = regnum;
> + rec.u.reg.len = register_size (gdbarch, regnum);
> + if (rec.u.reg.len > sizeof (rec.u.reg.u.buf))
> + rec.u.reg.u.ptr = (gdb_byte *) xmalloc (rec.u.reg.len);
>
> return rec;
> }
>
> -/* Free a record_full_reg record entry. */
> +/* Cleanup a record_full_reg record entry. */
>
> static inline void
> -record_full_reg_release (struct record_full_entry *rec)
> +record_full_reg_cleanup (struct record_full_entry rec)
> {
> - gdb_assert (rec->type == record_full_reg);
> - if (rec->u.reg.len > sizeof (rec->u.reg.u.buf))
> - xfree (rec->u.reg.u.ptr);
> - xfree (rec);
> + gdb_assert (rec.type == record_full_reg);
> + if (rec.u.reg.len > sizeof (rec.u.reg.u.buf))
> + xfree (rec.u.reg.u.ptr);
> }
>
> -/* Alloc a record_full_mem record entry. */
> +/* Init a record_full_mem record entry. */
>
> -static inline struct record_full_entry *
> -record_full_mem_alloc (CORE_ADDR addr, int len)
> +static inline struct record_full_entry
> +record_full_mem_init (CORE_ADDR addr, int len)
> {
> - struct record_full_entry *rec;
> + struct record_full_entry rec;
>
> - rec = XCNEW (struct record_full_entry);
> - rec->type = record_full_mem;
> - rec->u.mem.addr = addr;
> - rec->u.mem.len = len;
> - if (rec->u.mem.len > sizeof (rec->u.mem.u.buf))
> - rec->u.mem.u.ptr = (gdb_byte *) xmalloc (len);
> + rec.type = record_full_mem;
> + rec.u.mem.addr = addr;
> + rec.u.mem.len = len;
> + if (rec.u.mem.len > sizeof (rec.u.mem.u.buf))
> + rec.u.mem.u.ptr = (gdb_byte *) xmalloc (len);
> + rec.u.mem.mem_entry_not_accessible = 0;
>
> return rec;
> }
>
> -/* Free a record_full_mem record entry. */
> +/* Cleanup a record_full_mem record entry. */
>
> static inline void
> -record_full_mem_release (struct record_full_entry *rec)
> -{
> - gdb_assert (rec->type == record_full_mem);
> - if (rec->u.mem.len > sizeof (rec->u.mem.u.buf))
> - xfree (rec->u.mem.u.ptr);
> - xfree (rec);
> -}
> -
> -/* Alloc a record_full_end record entry. */
> -
> -static inline struct record_full_entry *
> -record_full_end_alloc (void)
> +record_full_mem_cleanup (struct record_full_entry rec)
> {
> - struct record_full_entry *rec;
> -
> - rec = XCNEW (struct record_full_entry);
> - rec->type = record_full_end;
> -
> - return rec;
> + gdb_assert (rec.type == record_full_mem);
> + if (rec.u.mem.len > sizeof (rec.u.mem.u.buf))
> + xfree (rec.u.mem.u.ptr);
> }
>
> -/* Free a record_full_end record entry. */
> +/* Free one record entry, any type. */
>
> static inline void
> -record_full_end_release (struct record_full_entry *rec)
> -{
> - xfree (rec);
> -}
> -
> -/* Free one record entry, any type.
> - Return entry->type, in case caller wants to know. */
> -
> -static inline enum record_full_type
> -record_full_entry_release (struct record_full_entry *rec)
> +record_full_entry_cleanup (struct record_full_entry rec)
> {
> - enum record_full_type type = rec->type;
>
> - switch (type) {
> + switch (rec.type) {
> case record_full_reg:
> - record_full_reg_release (rec);
> + record_full_reg_cleanup (rec);
> break;
> case record_full_mem:
> - record_full_mem_release (rec);
> - break;
> - case record_full_end:
> - record_full_end_release (rec);
> + record_full_mem_cleanup (rec);
> break;
> }
> - return type;
> }
>
> -/* Free all record entries in list pointed to by REC. */
> -
> static void
> -record_full_list_release (struct record_full_entry *rec)
> +record_full_reset_history ()
> {
> - if (!rec)
> - return;
> -
> - while (rec->next)
> - rec = rec->next;
> + record_full_insn_num = 0;
> + record_full_insn_count = 0;
> + record_full_next_insn = 0;
>
> - while (rec->prev)
> + for (auto &insn : record_full_list)
> {
> - rec = rec->prev;
> - record_full_entry_release (rec->next);
> + for (auto &entry : insn.effects)
> + record_full_entry_cleanup (entry);
> }
>
> - if (rec == &record_full_first)
> - {
> - record_full_insn_num = 0;
> - record_full_first.next = NULL;
> - }
> - else
> - record_full_entry_release (rec);
> + record_full_list.clear ();
> }
>
> -/* Free all record entries forward of the given list position. */
> -
> static void
> -record_full_list_release_following (struct record_full_entry *rec)
> +record_full_list_release_following (int index)
> {
> - struct record_full_entry *tmp = rec->next;
> -
> - rec->next = NULL;
> - while (tmp)
> + for (int i = record_full_list.size () - 1; i > index; i--)
> {
> - rec = tmp->next;
> - if (record_full_entry_release (tmp) == record_full_end)
> - {
> - record_full_insn_num--;
> - record_full_insn_count--;
> - }
> - tmp = rec;
> + for (auto &entry : record_full_list[i].effects)
> + record_full_entry_cleanup (entry);
> + record_full_list.pop_back ();
> }
> + /* Set the next instruction to be past the end of the log so we
> + start recording if the user moves forward again. */
> + record_full_next_insn = index;
> +}
> +
> +static void
> +record_full_save_instruction ()
> +{
> + ++record_full_insn_count;
> + record_full_incomplete_instruction.insn_num = record_full_insn_count;
> + record_full_incomplete_instruction.effects.shrink_to_fit ();
> + record_full_list.push_back (record_full_incomplete_instruction);
> + record_full_next_insn++;
> }
>
> /* Delete the first instruction from the beginning of the log, to make
> @@ -550,52 +504,22 @@ record_full_list_release_following (struct
> record_full_entry *rec)
> static void
> record_full_list_release_first (void)
> {
> - struct record_full_entry *tmp;
> -
> - if (!record_full_first.next)
> + if (record_full_list.empty ())
> return;
>
> - /* Loop until a record_full_end. */
> - while (1)
> - {
> - /* Cut record_full_first.next out of the linked list. */
> - tmp = record_full_first.next;
> - record_full_first.next = tmp->next;
> - tmp->next->prev = &record_full_first;
> -
> - /* tmp is now isolated, and can be deleted. */
> - if (record_full_entry_release (tmp) == record_full_end)
> - break; /* End loop at first record_full_end. */
> + for (auto &entry : record_full_list[0].effects)
> + record_full_entry_cleanup (entry);
>
> - if (!record_full_first.next)
> - {
> - gdb_assert (record_full_insn_num == 1);
> - break; /* End loop when list is empty. */
> - }
> - }
> + record_full_list.pop_front ();
> + --record_full_next_insn;
> }
>
> /* Add a struct record_full_entry to record_full_arch_list. */
>
> static void
> -record_full_arch_list_add (struct record_full_entry *rec)
> +record_full_arch_list_add (struct record_full_entry &rec)
> {
> - if (record_debug > 1)
> - gdb_printf (gdb_stdlog,
> - "Process record: record_full_arch_list_add %s.\n",
> - host_address_to_string (rec));
> -
> - if (record_full_arch_list_tail)
> - {
> - record_full_arch_list_tail->next = rec;
> - rec->prev = record_full_arch_list_tail;
> - record_full_arch_list_tail = rec;
> - }
> - else
> - {
> - record_full_arch_list_head = rec;
> - record_full_arch_list_tail = rec;
> - }
> + record_full_incomplete_instruction.effects.push_back (rec);
> }
>
> /* Return the value storage location of a record entry. */
> @@ -613,7 +537,6 @@ record_full_get_loc (struct record_full_entry *rec)
> return rec->u.reg.u.ptr;
> else
> return rec->u.reg.u.buf;
> - case record_full_end:
> default:
> gdb_assert_not_reached ("unexpected record_full_entry type");
> return NULL;
> @@ -625,7 +548,7 @@ record_full_get_loc (struct record_full_entry *rec)
> int
> record_full_arch_list_add_reg (struct regcache *regcache, int regnum)
> {
> - struct record_full_entry *rec;
> + struct record_full_entry rec;
I think we can omit the struct keyword here (there are some more occurrences in this patch).
> if (record_debug > 1)
> gdb_printf (gdb_stdlog,
> @@ -633,9 +556,9 @@ record_full_arch_list_add_reg (struct regcache
> *regcache, int regnum)
> "record list.\n",
> regnum);
>
> - rec = record_full_reg_alloc (regcache, regnum);
> + rec = record_full_reg_init (regcache, regnum);
>
> - regcache->cooked_read (regnum, record_full_get_loc (rec));
> + regcache->cooked_read (regnum, record_full_get_loc (&rec));
>
> record_full_arch_list_add (rec);
>
> @@ -648,7 +571,7 @@ record_full_arch_list_add_reg (struct regcache
> *regcache, int regnum)
> int
> record_full_arch_list_add_mem (CORE_ADDR addr, int len)
> {
> - struct record_full_entry *rec;
> + struct record_full_entry rec;
>
> if (record_debug > 1)
> gdb_printf (gdb_stdlog,
> @@ -659,12 +582,12 @@ record_full_arch_list_add_mem (CORE_ADDR addr,
> int len)
> if (!addr) /* FIXME: Why? Some arch must permit it... */
> return 0;
>
> - rec = record_full_mem_alloc (addr, len);
> + rec = record_full_mem_init (addr, len);
>
> if (record_read_memory (current_inferior ()->arch (), addr,
> - record_full_get_loc (rec), len))
> + record_full_get_loc (&rec), len))
> {
> - record_full_mem_release (rec);
> + record_full_mem_cleanup (rec);
> return -1;
> }
>
> @@ -673,27 +596,6 @@ record_full_arch_list_add_mem (CORE_ADDR addr,
> int len)
> return 0;
> }
>
> -/* Add a record_full_end type struct record_full_entry to
> - record_full_arch_list. */
> -
> -int
> -record_full_arch_list_add_end (void)
> -{
> - struct record_full_entry *rec;
> -
> - if (record_debug > 1)
> - gdb_printf (gdb_stdlog,
> - "Process record: add end to arch list.\n");
> -
> - rec = record_full_end_alloc ();
> - rec->u.end.sigval = GDB_SIGNAL_0;
> - rec->u.end.insn_num = ++record_full_insn_count;
> -
> - record_full_arch_list_add (rec);
> -
> - return 0;
> -}
> -
> static void
> record_full_check_insn_num (void)
> {
> @@ -725,8 +627,7 @@ record_full_message (struct regcache *regcache,
> enum gdb_signal signal)
>
> try
> {
> - record_full_arch_list_head = NULL;
> - record_full_arch_list_tail = NULL;
> + record_full_reset_incomplete ();
>
> /* Check record_full_insn_num. */
> record_full_check_insn_num ();
> @@ -746,20 +647,16 @@ record_full_message (struct regcache *regcache,
> enum gdb_signal signal)
> the user says something different, like "deliver this signal"
> during the replay mode).
>
> - User should understand that nothing he does during the replay
> - mode will change the behavior of the child. If he tries,
> + User should understand that nothing they do during the replay
> + mode will change the behavior of the child. If they try,
> then that is a user error.
>
> But we should still deliver the signal to gdb during the replay,
> if we delivered it during the recording. Therefore we should
> record the signal during record_full_wait, not
> record_full_resume. */
> - if (record_full_list != &record_full_first) /* FIXME better way
> - to check */
> - {
> - gdb_assert (record_full_list->type == record_full_end);
> - record_full_list->u.end.sigval = signal;
> - }
> + if (signal != GDB_SIGNAL_0)
> + record_full_list[record_full_next_insn - 1].sigval = signal;
>
> if (signal == GDB_SIGNAL_0
> || !gdbarch_process_record_signal_p (gdbarch))
> @@ -778,13 +675,11 @@ record_full_message (struct regcache *regcache,
> enum gdb_signal signal)
> }
> catch (const gdb_exception &ex)
> {
> - record_full_list_release (record_full_arch_list_tail);
> + record_full_reset_incomplete ();
> throw;
> }
>
> - record_full_list->next = record_full_arch_list_head;
> - record_full_arch_list_head->prev = record_full_list;
> - record_full_list = record_full_arch_list_tail;
> + record_full_save_instruction ();
>
> if (record_full_insn_num == record_full_insn_max_num)
> record_full_list_release_first ();
> @@ -829,9 +724,9 @@ static enum target_stop_reason
> record_full_stop_reason
> entries and memory entries, followed by an 'end' entry. */
>
> static inline void
> -record_full_exec_insn (struct regcache *regcache,
> - struct gdbarch *gdbarch,
> - struct record_full_entry *entry)
> +record_full_exec_entry (struct regcache *regcache,
> + struct gdbarch *gdbarch,
> + struct record_full_entry *entry)
Nit: omit struct keywords
And there are some more places in this series/patch, but I will stop commenting
now on all of them.
> {
> switch (entry->type)
> {
> @@ -909,6 +804,15 @@ record_full_exec_insn (struct regcache *regcache,
> }
> }
>
> +static inline void
> +record_full_exec_insn (struct regcache *regcache,
> + struct gdbarch *gdbarch,
> + record_full_instruction &insn)
> +{
> + for (auto &entry : insn.effects)
> + record_full_exec_entry (regcache, gdbarch, &entry);
> +}
> +
> static void record_full_restore (struct bfd &cbfd);
>
> /* Asynchronous signal handle registered as event loop source for when
> @@ -983,10 +887,7 @@ record_full_open (const char *args, int from_tty)
> record_preopen ();
>
> /* Reset */
> - record_full_insn_num = 0;
> - record_full_insn_count = 0;
> - record_full_list = &record_full_first;
> - record_full_list->next = NULL;
> + record_full_reset_history ();
>
> bfd *cbfd = get_inferior_core_bfd (current_inferior ());
> if (cbfd != nullptr)
> @@ -1014,7 +915,7 @@ record_full_base_target::close ()
> if (record_debug)
> gdb_printf (gdb_stdlog, "Process record: record_full_close\n");
>
> - record_full_list_release (record_full_list);
> + record_full_reset_history ();
>
> /* Release record_full_core_regbuf. */
> if (record_full_core_regbuf)
> @@ -1313,7 +1214,6 @@ record_full_wait_1 (struct target_ops *ops,
> struct gdbarch *gdbarch = regcache->arch ();
> const address_space *aspace = current_inferior ()->aspace.get ();
> int continue_flag = 1;
> - int first_record_full_end = 1;
>
> try
> {
> @@ -1322,7 +1222,6 @@ record_full_wait_1 (struct target_ops *ops,
> record_full_stop_reason = TARGET_STOPPED_BY_NO_REASON;
> status->set_stopped (GDB_SIGNAL_0);
>
> - /* Check breakpoint when forward execute. */
> if (execution_direction == EXEC_FORWARD)
> {
> tmp_pc = regcache_read_pc (regcache);
> @@ -1330,8 +1229,7 @@ record_full_wait_1 (struct target_ops *ops,
>
> &record_full_stop_reason))
> {
> if (record_debug)
> - gdb_printf (gdb_stdlog,
> - "Process record: break at %s.\n",
> + gdb_printf (gdb_stdlog, "Process record: break at %s.\n",
> paddress (gdbarch, tmp_pc));
> goto replay_out;
> }
> @@ -1344,10 +1242,10 @@ record_full_wait_1 (struct target_ops *ops,
> the signal. */
> target_terminal::ours ();
>
> - /* In EXEC_FORWARD mode, record_full_list points to the tail of prev
> - instruction. */
> - if (execution_direction == EXEC_FORWARD && record_full_list->next)
> - record_full_list = record_full_list->next;
> + /* In EXEC_FORWARD mode, record_full_next_insn is the next
> + instruction to be executed. */
> + if (execution_direction == EXEC_REVERSE)
> + record_full_next_insn--;
>
> /* Loop over the record_full_list, looking for the next place to
> stop. */
> @@ -1355,108 +1253,92 @@ record_full_wait_1 (struct target_ops *ops,
> {
> /* Check for beginning and end of log. */
> if (execution_direction == EXEC_REVERSE
> - && record_full_list == &record_full_first)
> + && record_full_next_insn < 0)
> {
> /* Hit beginning of record log in reverse. */
> status->set_no_history ();
> + record_full_next_insn = 0;
> break;
> }
> if (execution_direction != EXEC_REVERSE
> - && !record_full_list->next)
> + && record_full_next_insn == record_full_list.size ())
> {
> /* Hit end of record log going forward. */
> status->set_no_history ();
> break;
> }
>
> - record_full_exec_insn (regcache, gdbarch, record_full_list);
> + record_full_exec_insn
> + (regcache, gdbarch,
> + record_full_list[record_full_next_insn]);
>
> - if (record_full_list->type == record_full_end)
> + /* step */
> + if (record_full_resume_step)
> {
> if (record_debug > 1)
> - gdb_printf
> - (gdb_stdlog,
> - "Process record: record_full_end %s to "
> - "inferior.\n",
> - host_address_to_string (record_full_list));
> -
> - if (first_record_full_end
> - && execution_direction == EXEC_REVERSE)
> - {
> - /* When reverse execute, the first
> - record_full_end is the part of current
> - instruction. */
> - first_record_full_end = 0;
> - }
> - else
> - {
> - /* In EXEC_REVERSE mode, this is the
> - record_full_end of prev instruction. In
> - EXEC_FORWARD mode, this is the
> - record_full_end of current instruction. */
> - /* step */
> - if (record_full_resume_step)
> - {
> - if (record_debug > 1)
> - gdb_printf (gdb_stdlog,
> - "Process record: step.\n");
> - continue_flag = 0;
> - }
> -
> - /* check breakpoint */
> - tmp_pc = regcache_read_pc (regcache);
> - if (record_check_stopped_by_breakpoint
> - (aspace, tmp_pc, &record_full_stop_reason))
> - {
> - if (record_debug)
> - gdb_printf (gdb_stdlog,
> - "Process record: break "
> - "at %s.\n",
> - paddress (gdbarch, tmp_pc));
> + gdb_printf (gdb_stdlog,
> + "Process record: step.\n");
> + continue_flag = 0;
> + }
>
> - continue_flag = 0;
> - }
> + /* check breakpoint */
> + tmp_pc = regcache_read_pc (regcache);
> + if (record_check_stopped_by_breakpoint
> + (aspace, tmp_pc, &record_full_stop_reason))
> + {
> + if (record_debug)
> + gdb_printf (gdb_stdlog,
> + "Process record: break "
> + "at %s.\n",
> + paddress (gdbarch, tmp_pc));
>
> - if (record_full_stop_reason
> - == TARGET_STOPPED_BY_WATCHPOINT)
> - {
> - if (record_debug)
> - gdb_printf (gdb_stdlog,
> - "Process record: hit hw "
> - "watchpoint.\n");
> - continue_flag = 0;
> - }
> - /* Check target signal */
> - if (record_full_list->u.end.sigval != GDB_SIGNAL_0)
> - /* FIXME: better way to check */
> - continue_flag = 0;
> - }
> + continue_flag = 0;
> }
>
> - if (continue_flag)
> + if (record_full_stop_reason
> + == TARGET_STOPPED_BY_WATCHPOINT)
> {
> - if (execution_direction == EXEC_REVERSE)
> - {
> - if (record_full_list->prev)
> - record_full_list = record_full_list->prev;
> - }
> - else
> - {
> - if (record_full_list->next)
> - record_full_list = record_full_list->next;
> - }
> + if (record_debug)
> + gdb_printf (gdb_stdlog,
> + "Process record: hit hw "
> + "watchpoint.\n");
> + continue_flag = 0;
> }
> + if (record_full_list[record_full_next_insn].sigval.has_value ())
> + continue_flag = 0;
> +
> + if (execution_direction == EXEC_REVERSE)
> + record_full_next_insn--;
> + else
> + record_full_next_insn++;
> }
> while (continue_flag);
>
> + if (record_full_next_insn < 0)
> + {
> + gdb_assert (execution_direction == EXEC_REVERSE);
> + record_full_next_insn = 0;
> + }
> + else if (record_full_next_insn > record_full_list.size ())
> + {
> + gdb_assert (execution_direction == EXEC_FORWARD);
> + record_full_next_insn = record_full_list.size ();
> + }
> + /* Reset the current instruciton to point to the one to be replayed
Nit: instruction
> + moving forward. */
> + else if (execution_direction == EXEC_REVERSE)
> + record_full_next_insn++;
> +
> replay_out:
> if (status->kind () == TARGET_WAITKIND_STOPPED)
> {
> + int insn = (execution_direction == EXEC_FORWARD)
> + ? record_full_next_insn - 1 : record_full_next_insn;
> if (record_full_get_sig)
> status->set_stopped (GDB_SIGNAL_INT);
> - else if (record_full_list->u.end.sigval != GDB_SIGNAL_0)
> - /* FIXME: better way to check */
> - status->set_stopped (record_full_list->u.end.sigval);
> + else if (record_full_list[insn].sigval.has_value ())
> + status->set_stopped
> + (record_full_list[insn].sigval.value ());
> else
> status->set_stopped (GDB_SIGNAL_TRAP);
> }
> @@ -1464,12 +1346,9 @@ record_full_wait_1 (struct target_ops *ops,
> catch (const gdb_exception &ex)
> {
> if (execution_direction == EXEC_REVERSE)
> - {
> - if (record_full_list->next)
> - record_full_list = record_full_list->next;
> - }
> + record_full_next_insn++;
> else
> - record_full_list = record_full_list->prev;
> + record_full_next_insn--;
>
> throw;
> }
> @@ -1557,8 +1436,7 @@ record_full_registers_change (struct regcache
> *regcache, int regnum)
> /* Check record_full_insn_num. */
> record_full_check_insn_num ();
>
> - record_full_arch_list_head = NULL;
> - record_full_arch_list_tail = NULL;
> + record_full_reset_incomplete ();
>
> if (regnum < 0)
> {
> @@ -1568,7 +1446,7 @@ record_full_registers_change (struct regcache
> *regcache, int regnum)
> {
> if (record_full_arch_list_add_reg (regcache, i))
> {
> - record_full_list_release (record_full_arch_list_tail);
> + record_full_reset_incomplete ();
> error (_("Process record: failed to record execution log."));
> }
> }
> @@ -1577,18 +1455,11 @@ record_full_registers_change (struct regcache
> *regcache, int regnum)
> {
> if (record_full_arch_list_add_reg (regcache, regnum))
> {
> - record_full_list_release (record_full_arch_list_tail);
> + record_full_reset_incomplete ();
> error (_("Process record: failed to record execution log."));
> }
> }
> - if (record_full_arch_list_add_end ())
> - {
> - record_full_list_release (record_full_arch_list_tail);
> - error (_("Process record: failed to record execution log."));
> - }
> - record_full_list->next = record_full_arch_list_head;
> - record_full_arch_list_head->prev = record_full_list;
> - record_full_list = record_full_arch_list_tail;
> + record_full_save_instruction ();
>
> if (record_full_insn_num == record_full_insn_max_num)
> record_full_list_release_first ();
> @@ -1607,7 +1478,7 @@ record_full_target::store_registers (struct
> regcache *regcache, int regno)
> {
> int n;
>
> - /* Let user choose if he wants to write register or not. */
> + /* Let user choose if they want to write register or not. */
> if (regno < 0)
> n =
> query (_("Because GDB is in replay mode, changing the "
> @@ -1642,7 +1513,7 @@ record_full_target::store_registers (struct
> regcache *regcache, int regno)
> }
>
> /* Destroy the record from here forward. */
> - record_full_list_release_following (record_full_list);
> + record_full_list_release_following (record_full_next_insn);
> }
>
> record_full_registers_change (regcache, regno);
> @@ -1675,36 +1546,24 @@ record_full_target::xfer_partial (enum
> target_object object,
> error (_("Process record canceled the operation."));
>
> /* Destroy the record from here forward. */
> - record_full_list_release_following (record_full_list);
> + record_full_list_release_following (record_full_next_insn);
> }
>
> /* Check record_full_insn_num */
> record_full_check_insn_num ();
>
> /* Record registers change to list as an instruction. */
> - record_full_arch_list_head = NULL;
> - record_full_arch_list_tail = NULL;
> + record_full_reset_incomplete ();
> if (record_full_arch_list_add_mem (offset, len))
> {
> - record_full_list_release (record_full_arch_list_tail);
> + record_full_reset_incomplete ();
> if (record_debug)
> gdb_printf (gdb_stdlog,
> "Process record: failed to record "
> "execution log.");
> return TARGET_XFER_E_IO;
> }
> - if (record_full_arch_list_add_end ())
> - {
> - record_full_list_release (record_full_arch_list_tail);
> - if (record_debug)
> - gdb_printf (gdb_stdlog,
> - "Process record: failed to record "
> - "execution log.");
> - return TARGET_XFER_E_IO;
> - }
> - record_full_list->next = record_full_arch_list_head;
> - record_full_arch_list_head->prev = record_full_list;
> - record_full_list = record_full_arch_list_tail;
> + record_full_save_instruction ();
>
> if (record_full_insn_num == record_full_insn_max_num)
> record_full_list_release_first ();
> @@ -1866,8 +1725,7 @@ record_full_base_target::get_bookmark (const char
> *args, int from_tty)
> char *ret = NULL;
>
> /* Return stringified form of instruction count. */
> - if (record_full_list && record_full_list->type == record_full_end)
> - ret = xstrdup (pulongest (record_full_list->u.end.insn_num));
> + ret = xstrdup (pulongest (record_full_list[record_full_next_insn].insn_num));
I think we can get here with an empty record_full_list - in case we are in recording mode,
no instructions have been logged and this function is called:
~~~
(gdb) info record
Active record target: record-full
Record mode:
No instructions have been logged.
Max logged instructions is 200000.
(gdb) bookmark
Thread 1 "gdb-up" hit Breakpoint 1, record_full_base_target::get_bookmark (this=0x555558392900 <record_full_ops>, args=0x0, from_tty=1) at /tmp/record-full.c:1774
1774 char *ret = NULL;
(gdb) p record_full_next_insn
$1 = 0
(gdb) p record_full_list.empty ()
$2 = true
~~~
> if (record_debug)
> {
> @@ -1923,30 +1781,22 @@ record_full_base_target::record_method (ptid_t
> ptid)
> void
> record_full_base_target::info_record ()
> {
> - struct record_full_entry *p;
> -
> if (RECORD_FULL_IS_REPLAY)
> gdb_printf (_("Replay mode:\n"));
> else
> gdb_printf (_("Record mode:\n"));
>
> - /* Find entry for first actual instruction in the log. */
> - for (p = record_full_first.next;
> - p != NULL && p->type != record_full_end;
> - p = p->next)
> - ;
> -
> /* Do we have a log at all? */
> - if (p != NULL && p->type == record_full_end)
> + if (!record_full_list.empty ())
> {
> /* Display instruction number for first instruction in the log. */
> - gdb_printf (_("Lowest recorded instruction number is %s.\n"),
> - pulongest (p->u.end.insn_num));
> + gdb_printf (_("Lowest recorded instruction number is %u.\n"),
> + record_full_list[0].insn_num);
>
> /* If in replay mode, display where we are in the log. */
> if (RECORD_FULL_IS_REPLAY)
> - gdb_printf (_("Current instruction number is %s.\n"),
> - pulongest (record_full_list->u.end.insn_num));
> + gdb_printf (_("Current instruction number is %u.\n"),
> + record_full_list[record_full_next_insn].insn_num);
>
> /* Display instruction number for last instruction in the log. */
> gdb_printf (_("Highest recorded instruction number is %s.\n"),
> @@ -1975,7 +1825,7 @@ record_full_base_target::supports_delete_record ()
> void
> record_full_base_target::delete_record ()
> {
> - record_full_list_release_following (record_full_list);
> + record_full_reset_history ();
> }
>
> /* The "record_is_replaying" target method. */
> @@ -2001,23 +1851,23 @@ record_full_base_target::record_will_replay
> (ptid_t ptid, int dir)
> /* Go to a specific entry. */
>
> static void
> -record_full_goto_entry (struct record_full_entry *p)
> +record_full_goto_entry (size_t target_insn)
> {
> - if (p == NULL)
> + if (target_insn >= record_full_list.size ())
> error (_("Target insn not found."));
> - else if (p == record_full_list)
> + else if (target_insn == record_full_next_insn)
> error (_("Already at target insn."));
> - else if (p->u.end.insn_num > record_full_list->u.end.insn_num)
> + else if (target_insn > record_full_next_insn)
> {
> gdb_printf (_("Go forward to insn number %s\n"),
> - pulongest (p->u.end.insn_num));
> - record_full_goto_insn (p, EXEC_FORWARD);
> + pulongest (record_full_list[target_insn].insn_num));
> + record_full_goto_insn (target_insn, EXEC_FORWARD);
> }
> else
> {
> gdb_printf (_("Go backward to insn number %s\n"),
> - pulongest (p->u.end.insn_num));
> - record_full_goto_insn (p, EXEC_REVERSE);
> + pulongest (target_insn));
> + record_full_goto_insn (target_insn, EXEC_REVERSE);
> }
>
> registers_changed ();
> @@ -2033,13 +1883,7 @@ record_full_goto_entry (struct record_full_entry
> *p)
> void
> record_full_base_target::goto_record_begin ()
> {
> - struct record_full_entry *p = NULL;
> -
> - for (p = &record_full_first; p != NULL; p = p->next)
> - if (p->type == record_full_end)
> - break;
> -
> - record_full_goto_entry (p);
> + record_full_goto_entry (0);
> }
>
> /* The "goto_record_end" target method. */
> @@ -2047,15 +1891,7 @@ record_full_base_target::goto_record_begin ()
> void
> record_full_base_target::goto_record_end ()
> {
> - struct record_full_entry *p = NULL;
> -
> - for (p = record_full_list; p->next != NULL; p = p->next)
> - ;
> - for (; p!= NULL; p = p->prev)
> - if (p->type == record_full_end)
> - break;
> -
> - record_full_goto_entry (p);
> + record_full_goto_entry (record_full_list.size () -1);
Nit: whitespace before 1 => "record_full_list.size () - 1"
And in case the record_full_list is empty, won't we call
record_full_goto_entry with an invalid value for target_insn ?
> }
>
> /* The "goto_record" target method. */
> @@ -2063,13 +1899,7 @@ record_full_base_target::goto_record_end ()
> void
> record_full_base_target::goto_record (ULONGEST target_insn)
> {
> - struct record_full_entry *p = NULL;
> -
> - for (p = &record_full_first; p != NULL; p = p->next)
> - if (p->type == record_full_end && p->u.end.insn_num == target_insn)
> - break;
> -
> - record_full_goto_entry (p);
> + record_full_goto_entry (target_insn);
> }
>
> /* The "record_stop_replaying" target method. */
> @@ -2339,19 +2169,96 @@ netorder32 (uint32_t input)
> return ret;
> }
>
> +static void
> +record_full_read_entry_from_bfd (bfd *cbfd, asection *osec, int *bfd_offset)
> +{
> + uint8_t rectype;
> + uint32_t regnum, len;
> + uint64_t addr;
> + regcache *cache = get_thread_regcache (inferior_thread ());
> +
> + bfdcore_read (cbfd, osec, &rectype, sizeof (rectype), bfd_offset);
> + switch (rectype)
> + {
> + case record_full_reg: /* reg */
> + {
> + /* Get register number to regnum. */
> + bfdcore_read (cbfd, osec, ®num, sizeof (regnum), bfd_offset);
> + regnum = netorder32 (regnum);
> +
> + record_full_entry rec;
> +
> + rec = record_full_reg_init (cache, regnum);
> +
> + /* Get val. */
> + bfdcore_read (cbfd, osec, record_full_get_loc (&rec),
> + rec.u.reg.len, bfd_offset);
> +
> + if (record_debug)
> + gdb_printf (gdb_stdlog,
> + " Reading register %d (1 "
> + "plus %lu plus %d bytes)\n",
> + rec.u.reg.num,
> + (unsigned long) sizeof (regnum),
> + rec.u.reg.len);
> +
> + record_full_arch_list_add (rec);
> + break;
> + }
> +
> + case record_full_mem: /* mem */
> + {
> + /* Get len. */
> + bfdcore_read (cbfd, osec, &len, sizeof (len), bfd_offset);
> + len = netorder32 (len);
> +
> + /* Get addr. */
> + bfdcore_read (cbfd, osec, &addr, sizeof (addr),
> + bfd_offset);
> + addr = netorder64 (addr);
> +
> + record_full_entry rec;
> + rec = record_full_mem_init (addr, len);
> +
> + /* Get val. */
> + bfdcore_read (cbfd, osec, record_full_get_loc (&rec), len,
> + bfd_offset);
> +
> + if (record_debug)
> + gdb_printf (gdb_stdlog,
> + " Reading memory %s (1 plus "
> + "%lu plus %lu plus %d bytes)\n",
> + paddress (get_current_arch (),
> + rec.u.mem.addr),
> + (unsigned long) sizeof (addr),
> + (unsigned long) sizeof (len),
> + len);
> +
> + record_full_arch_list_add (rec);
> + break;
> + }
> +
> + default:
> + error (_("Bad entry type %d, offset %d of %lu in core file %ps."),
> + rectype, *bfd_offset, bfd_section_size (osec),
> + styled_string (file_name_style.style (),
> + bfd_get_filename (cbfd)));
> + break;
> + }
> +}
> +
> /* Restore the execution log from core file CBFD. */
>
> static void
> record_full_restore (struct bfd &cbfd)
> {
> uint32_t magic;
> - struct record_full_entry *rec;
> asection *osec;
> uint32_t osec_size;
> int bfd_offset = 0;
>
> /* "record_full_restore" can only be called when record list is empty. */
> - gdb_assert (record_full_first.next == NULL);
> + gdb_assert (record_full_list.empty ());
>
> if (record_debug)
> gdb_printf (gdb_stdlog, "Restoring recording from core file.\n");
> @@ -2379,124 +2286,47 @@ record_full_restore (struct bfd &cbfd)
> "RECORD_FULL_FILE_MAGIC (0x%s)\n",
> phex_nz (netorder32 (magic), 4));
>
> - /* Restore the entries in recfd into record_full_arch_list_head and
> - record_full_arch_list_tail. */
> - record_full_arch_list_head = NULL;
> - record_full_arch_list_tail = NULL;
> record_full_insn_num = 0;
>
> try
> {
> - regcache *regcache = get_thread_regcache (inferior_thread ());
> -
> - while (1)
> + while (bfd_offset < osec_size)
> {
> - uint8_t rectype;
> - uint32_t regnum, len, signal, count;
> - uint64_t addr;
> -
> - /* We are finished when offset reaches osec_size. */
> - if (bfd_offset >= osec_size)
> - break;
> - bfdcore_read (&cbfd, osec, &rectype, sizeof (rectype), &bfd_offset);
> -
> - switch (rectype)
> + record_full_reset_incomplete ();
> + uint32_t eff_count = 0;
> + uint8_t sigval;
> + uint32_t insn_num;
> +
> + /* First read the generic information for an instruction. */
> + bfdcore_read (&cbfd, osec, &sigval, sizeof (uint8_t), &bfd_offset);
> + bfdcore_read (&cbfd, osec, &eff_count, sizeof (uint32_t),
> + &bfd_offset);
> + bfdcore_read (&cbfd, osec, &insn_num, sizeof (uint32_t),
> + &bfd_offset);
> +
> + record_full_incomplete_instruction.insn_num = netorder32
> (insn_num);
> + if (sigval != GDB_SIGNAL_0)
> + record_full_incomplete_instruction.sigval = (gdb_signal) sigval;
> +
> + eff_count = netorder32 (eff_count);
> +
> + /* This deals with all the side effects. */
> + while (eff_count > 0)
> {
There is one space too much indent.
> - case record_full_reg: /* reg */
> - /* Get register number to regnum. */
> - bfdcore_read (&cbfd, osec, ®num, sizeof (regnum),
> - &bfd_offset);
> - regnum = netorder32 (regnum);
> -
> - rec = record_full_reg_alloc (regcache, regnum);
> -
> - /* Get val. */
> - bfdcore_read (&cbfd, osec, record_full_get_loc (rec),
> - rec->u.reg.len, &bfd_offset);
> -
> - if (record_debug)
> - gdb_printf (gdb_stdlog,
> - " Reading register %d (1 "
> - "plus %lu plus %d bytes)\n",
> - rec->u.reg.num,
> - (unsigned long) sizeof (regnum),
> - rec->u.reg.len);
> - break;
> + eff_count--;
>
> - case record_full_mem: /* mem */
> - /* Get len. */
> - bfdcore_read (&cbfd, osec, &len, sizeof (len), &bfd_offset);
> - len = netorder32 (len);
> -
> - /* Get addr. */
> - bfdcore_read (&cbfd, osec, &addr, sizeof (addr), &bfd_offset);
> - addr = netorder64 (addr);
> -
> - rec = record_full_mem_alloc (addr, len);
> -
> - /* Get val. */
> - bfdcore_read (&cbfd, osec, record_full_get_loc (rec),
> - rec->u.mem.len, &bfd_offset);
> -
> - if (record_debug)
> - gdb_printf (gdb_stdlog,
> - " Reading memory %s (1 plus "
> - "%lu plus %lu plus %d bytes)\n",
> - paddress (get_current_arch (),
> - rec->u.mem.addr),
> - (unsigned long) sizeof (addr),
> - (unsigned long) sizeof (len),
> - rec->u.mem.len);
> - break;
> -
> - case record_full_end: /* end */
> - rec = record_full_end_alloc ();
> - record_full_insn_num ++;
> -
> - /* Get signal value. */
> - bfdcore_read (&cbfd, osec, &signal, sizeof (signal),
> - &bfd_offset);
> - signal = netorder32 (signal);
> - rec->u.end.sigval = (enum gdb_signal) signal;
> -
> - /* Get insn count. */
> - bfdcore_read (&cbfd, osec, &count, sizeof (count), &bfd_offset);
> - count = netorder32 (count);
> - rec->u.end.insn_num = count;
> - record_full_insn_count = count + 1;
> - if (record_debug)
> - gdb_printf (gdb_stdlog,
> - " Reading record_full_end (1 + "
> - "%lu + %lu bytes), offset == %s\n",
> - (unsigned long) sizeof (signal),
> - (unsigned long) sizeof (count),
> - paddress (get_current_arch (),
> - bfd_offset));
> - break;
> -
> - default:
> - error (_("Bad entry type in core file %ps."),
> - styled_string (file_name_style.style (),
> - bfd_get_filename (&cbfd)));
> - break;
> + record_full_read_entry_from_bfd (&cbfd, osec, &bfd_offset);
> }
>
> - /* Add rec to record arch list. */
> - record_full_arch_list_add (rec);
> + record_full_save_instruction ();
> }
> }
> catch (const gdb_exception &ex)
> {
> - record_full_list_release (record_full_arch_list_tail);
> + record_full_reset_incomplete ();
> throw;
> }
>
> - /* Add record_full_arch_list_head to the end of record list. */
> - record_full_first.next = record_full_arch_list_head;
> - record_full_arch_list_head->prev = &record_full_first;
> - record_full_arch_list_tail->next = NULL;
> - record_full_list = &record_full_first;
> -
> /* Update record_full_insn_max_num. */
> if (record_full_insn_num > record_full_insn_max_num)
> {
> @@ -2505,6 +2335,10 @@ record_full_restore (struct bfd &cbfd)
> record_full_insn_max_num);
> }
>
> + /* When loading a recording, we'll always start at the oldest possible
> + instruction, no matter where the original recording was stopped. */
> + record_full_next_insn = 0;
> +
> /* Succeeded. */
> gdb_printf (_("Restored records from core file %s.\n"),
> bfd_get_filename (&cbfd));
> @@ -2538,13 +2372,73 @@ cmd_record_full_restore (const char *args, int
> from_tty)
> record_full_open (nullptr, from_tty);
> }
>
> +static void
> +record_full_write_entry_to_bfd (record_full_entry &entry,
> + gdb_bfd_ref_ptr obfd,
> + asection *osec, int *bfd_offset,
> + struct gdbarch *gdbarch)
> +{
> + /* Save entry. */
> + uint8_t type;
> + uint32_t regnum, len;
> + uint64_t addr;
> +
> + type = entry.type;
> + bfdcore_write (obfd.get (), osec, &type, sizeof (type), bfd_offset);
> +
> + switch (entry.type)
> + {
> + case record_full_reg: /* reg */
> + if (record_debug)
> + gdb_printf (gdb_stdlog,
> + " Writing register %d (1 "
> + "plus %lu plus %d bytes)\n",
> + entry.u.reg.num,
> + (unsigned long) sizeof (regnum),
> + entry.u.reg.len);
> +
> + /* Write regnum. */
> + regnum = netorder32 (entry.u.reg.num);
> + bfdcore_write (obfd.get (), osec, ®num, sizeof (regnum), bfd_offset);
> +
> + /* Write regval. */
> + bfdcore_write (obfd.get (), osec, record_full_get_loc (&entry),
> + entry.u.reg.len, bfd_offset);
> + break;
> +
> + case record_full_mem: /* mem */
> + if (record_debug)
> + gdb_printf (gdb_stdlog,
> + " Writing memory %s (1 plus "
> + "%lu plus %lu plus %d bytes)\n",
> + paddress (gdbarch,
> + entry.u.mem.addr),
> + (unsigned long) sizeof (addr),
> + (unsigned long) sizeof (len),
> + entry.u.mem.len);
> +
> + /* Write memlen. */
> + len = netorder32 (entry.u.mem.len);
> + bfdcore_write (obfd.get (), osec, &len, sizeof (len), bfd_offset);
> +
> + /* Write memaddr. */
> + addr = netorder64 (entry.u.mem.addr);
> + bfdcore_write (obfd.get (), osec, &addr, sizeof (addr), bfd_offset);
> +
> + /* Write memval. */
> + bfdcore_write (obfd.get (), osec, record_full_get_loc (&entry),
> + entry.u.mem.len, bfd_offset);
> + break;
> + }
> +
> +}
> +
> /* Save the execution log to a file. We use a modified elf corefile
> format, with an extra section for our data. */
>
> void
> record_full_base_target::save_record (const char *recfilename)
> {
> - struct record_full_entry *cur_record_full_list;
> uint32_t magic;
> struct gdbarch *gdbarch;
> int save_size = 0;
> @@ -2562,9 +2456,6 @@ record_full_base_target::save_record (const char
> *recfilename)
> /* Arrange to remove the output file on failure. */
> gdb::unlinker unlink_file (recfilename);
>
> - /* Save the current record entry to "cur_record_full_list". */
> - cur_record_full_list = record_full_list;
> -
> /* Get the values of regcache and gdbarch. */
> regcache *regcache = get_thread_regcache (inferior_thread ());
> gdbarch = regcache->arch ();
> @@ -2574,34 +2465,27 @@ record_full_base_target::save_record (const
> char *recfilename)
> = record_full_gdb_operation_disable_set ();
>
> /* Reverse execute to the begin of record list. */
> - while (1)
> - {
> - /* Check for beginning and end of log. */
> - if (record_full_list == &record_full_first)
> - break;
> -
> - record_full_exec_insn (regcache, gdbarch, record_full_list);
> -
> - if (record_full_list->prev)
> - record_full_list = record_full_list->prev;
> - }
> + for (int i = record_full_next_insn - 1; i >= 0; i--)
> + record_full_exec_insn (regcache, gdbarch,
> + record_full_list[i]);
>
> /* Compute the size needed for the extra bfd section. */
> save_size = 4; /* magic cookie */
> - for (record_full_list = record_full_first.next; record_full_list;
> - record_full_list = record_full_list->next)
> - switch (record_full_list->type)
> - {
> - case record_full_end:
> - save_size += 1 + 4 + 4;
> - break;
> - case record_full_reg:
> - save_size += 1 + 4 + record_full_list->u.reg.len;
> - break;
> - case record_full_mem:
> - save_size += 1 + 4 + 8 + record_full_list->u.mem.len;
> - break;
> - }
> + for (int i = record_full_list.size () - 1; i >= 0; i--)
> + {
> + /* Number of effects of an instruction. */
> + save_size += sizeof (uint32_t) + sizeof (uint8_t) + sizeof (uint32_t);
> + for (auto &entry : record_full_list[i].effects)
> + switch (entry.type)
> + {
> + case record_full_reg:
> + save_size += 1 + 4 + entry.u.reg.len;
> + break;
> + case record_full_mem:
> + save_size += 1 + 4 + 8 + entry.u.mem.len;
> + break;
> + }
> + }
>
> /* Make the new bfd section. */
> osec = bfd_make_section_anyway_with_flags (obfd.get (), "precord",
> @@ -2630,108 +2514,32 @@ record_full_base_target::save_record (const
> char *recfilename)
>
> /* Save the entries to recfd and forward execute to the end of
> record list. */
> - record_full_list = &record_full_first;
> - while (1)
> + for (int i = 0; i < record_full_list.size (); i++)
> {
> - /* Save entry. */
> - if (record_full_list != &record_full_first)
> + uint32_t eff_count = (uint32_t) record_full_list[i].effects.size ();
> + uint32_t insn_num = record_full_list[i].insn_num;
> + uint8_t sigval = (record_full_list[i].sigval.has_value ())
> + ? record_full_list[i].sigval.value ()
> + : GDB_SIGNAL_0;
> +
> + /* Signal. */
> + bfdcore_write (obfd.get (), osec, &sigval, sizeof (sigval), &bfd_offset);
> + eff_count = netorder32 (eff_count);
> + /* Number of effects. */
> + bfdcore_write (obfd.get (), osec, &eff_count, sizeof (eff_count),
> + &bfd_offset);
> + /* Instruction number. */
> + bfdcore_write (obfd.get (), osec, &insn_num, sizeof (uint32_t),
> + &bfd_offset);
> +
> + for (auto &entry : record_full_list[i].effects)
> {
> - uint8_t type;
> - uint32_t regnum, len, signal, count;
> - uint64_t addr;
> -
> - type = record_full_list->type;
> - bfdcore_write (obfd.get (), osec, &type, sizeof (type), &bfd_offset);
> -
> - switch (record_full_list->type)
> - {
> - case record_full_reg: /* reg */
> - if (record_debug)
> - gdb_printf (gdb_stdlog,
> - " Writing register %d (1 "
> - "plus %lu plus %d bytes)\n",
> - record_full_list->u.reg.num,
> - (unsigned long) sizeof (regnum),
> - record_full_list->u.reg.len);
> -
> - /* Write regnum. */
> - regnum = netorder32 (record_full_list->u.reg.num);
> - bfdcore_write (obfd.get (), osec, ®num,
> - sizeof (regnum), &bfd_offset);
> -
> - /* Write regval. */
> - bfdcore_write (obfd.get (), osec,
> - record_full_get_loc (record_full_list),
> - record_full_list->u.reg.len, &bfd_offset);
> - break;
> -
> - case record_full_mem: /* mem */
> - if (record_debug)
> - gdb_printf (gdb_stdlog,
> - " Writing memory %s (1 plus "
> - "%lu plus %lu plus %d bytes)\n",
> - paddress (gdbarch,
> - record_full_list->u.mem.addr),
> - (unsigned long) sizeof (addr),
> - (unsigned long) sizeof (len),
> - record_full_list->u.mem.len);
> -
> - /* Write memlen. */
> - len = netorder32 (record_full_list->u.mem.len);
> - bfdcore_write (obfd.get (), osec, &len, sizeof (len),
> - &bfd_offset);
> -
> - /* Write memaddr. */
> - addr = netorder64 (record_full_list->u.mem.addr);
> - bfdcore_write (obfd.get (), osec, &addr,
> - sizeof (addr), &bfd_offset);
> -
> - /* Write memval. */
> - bfdcore_write (obfd.get (), osec,
> - record_full_get_loc (record_full_list),
> - record_full_list->u.mem.len, &bfd_offset);
> - break;
> -
> - case record_full_end:
> - if (record_debug)
> - gdb_printf (gdb_stdlog,
> - " Writing record_full_end (1 + "
> - "%lu + %lu bytes)\n",
> - (unsigned long) sizeof (signal),
> - (unsigned long) sizeof (count));
> - /* Write signal value. */
> - signal = netorder32 (record_full_list->u.end.sigval);
> - bfdcore_write (obfd.get (), osec, &signal,
> - sizeof (signal), &bfd_offset);
> -
> - /* Write insn count. */
> - count = netorder32 (record_full_list->u.end.insn_num);
> - bfdcore_write (obfd.get (), osec, &count,
> - sizeof (count), &bfd_offset);
> - break;
> - }
> + record_full_write_entry_to_bfd (entry, obfd, osec, &bfd_offset,
> + gdbarch);
> }
> -
> /* Execute entry. */
> - record_full_exec_insn (regcache, gdbarch, record_full_list);
> -
> - if (record_full_list->next)
> - record_full_list = record_full_list->next;
> - else
> - break;
> - }
> -
> - /* Reverse execute to cur_record_full_list. */
> - while (1)
> - {
> - /* Check for beginning and end of log. */
> - if (record_full_list == cur_record_full_list)
> - break;
> -
> - record_full_exec_insn (regcache, gdbarch, record_full_list);
> -
> - if (record_full_list->prev)
> - record_full_list = record_full_list->prev;
> + if (i < record_full_next_insn)
> + record_full_exec_insn (regcache, gdbarch, record_full_list[i]);
> }
>
> unlink_file.keep ();
> @@ -2746,7 +2554,7 @@ record_full_base_target::save_record (const char
> *recfilename)
> correspondingly. */
>
> static void
> -record_full_goto_insn (struct record_full_entry *entry,
> +record_full_goto_insn (size_t target_insn,
> enum exec_direction_kind dir)
You could explain the new parameter in the function description.
> {
> scoped_restore restore_operation_disable
> @@ -2757,17 +2565,12 @@ record_full_goto_insn (struct record_full_entry
> *entry,
> /* Assume everything is valid: we will hit the entry,
> and we will not hit the end of the recording. */
>
> - if (dir == EXEC_FORWARD)
> - record_full_list = record_full_list->next;
> -
> - do
> - {
> - record_full_exec_insn (regcache, gdbarch, record_full_list);
> - if (dir == EXEC_REVERSE)
> - record_full_list = record_full_list->prev;
> - else
> - record_full_list = record_full_list->next;
> - } while (record_full_list != entry);
> + if (dir == EXEC_REVERSE)
> + for (int i = record_full_next_insn; i > target_insn; i--)
> + record_full_exec_insn (regcache, gdbarch, record_full_list[i - 1]);
> + else
> + for (int i = record_full_next_insn; i < target_insn; i++)
> + record_full_exec_insn (regcache, gdbarch, record_full_list[i]);
> }
>
> /* Alias for "target record-full". */
> @@ -2798,61 +2601,36 @@ set_record_full_insn_max_num (const char
> *args, int from_tty,
> static void
> maintenance_print_record_instruction (const char *args, int from_tty)
> {
> - struct record_full_entry *to_print = record_full_list;
> + if (record_full_list.empty ())
> + error (_("Not enough recorded history"));
>
> + int offset = record_full_next_insn - 1;
> + /* Reduce the offset by 1 if the record_full_next_insn is after the end
> + so that we show the last recorded instruction instead of crashing. */
> + if (offset == record_full_list.size ())
> + offset--;
> if (args != nullptr)
> {
> - int offset = value_as_long (parse_and_eval (args));
> - if (offset > 0)
> - {
> - /* Move forward OFFSET instructions. We know we found the
> - end of an instruction when to_print->type is record_full_end. */
> - while (to_print->next != nullptr && offset > 0)
> - {
> - to_print = to_print->next;
> - if (to_print->type == record_full_end)
> - offset--;
> - }
> - if (offset != 0)
> - error (_("Not enough recorded history"));
> - }
> - else
> - {
> - while (to_print->prev != nullptr && offset < 0)
> - {
> - to_print = to_print->prev;
> - if (to_print->type == record_full_end)
> - offset++;
> - }
> - if (offset != 0)
> - error (_("Not enough recorded history"));
> - }
> + offset += value_as_long (parse_and_eval (args));
> + if (offset >= record_full_list.size () || offset < 0)
> + error (_("Not enough recorded history"));
> }
> - gdb_assert (to_print != nullptr);
> + auto to_print = record_full_list.begin () + offset;
>
> gdbarch *arch = current_inferior ()->arch ();
>
> - /* Go back to the start of the instruction. */
> - while (to_print->prev != nullptr && to_print->prev->type != record_full_end)
> - to_print = to_print->prev;
> -
> - /* if we're in the first record, there are no actual instructions
> - recorded. Warn the user and leave. */
> - if (to_print == &record_full_first)
> - error (_("Not enough recorded history"));
> -
> - while (to_print->type != record_full_end)
> + for (auto entry : to_print->effects)
> {
> - switch (to_print->type)
> + switch (entry.type)
> {
> case record_full_reg:
> {
> - type *regtype = gdbarch_register_type (arch, to_print-
> >u.reg.num);
> + type *regtype = gdbarch_register_type (arch, entry.u.reg.num);
> value *val
> = value_from_contents (regtype,
> - record_full_get_loc (to_print));
> + record_full_get_loc (&entry));
> gdb_printf ("Register %s changed: ",
> - gdbarch_register_name (arch, to_print-
> >u.reg.num));
> + gdbarch_register_name (arch, entry.u.reg.num));
> struct value_print_options opts;
> get_user_print_options (&opts);
> opts.raw = true;
> @@ -2862,17 +2640,16 @@ maintenance_print_record_instruction (const
> char *args, int from_tty)
> }
> case record_full_mem:
> {
> - gdb_byte *b = record_full_get_loc (to_print);
> + gdb_byte *b = record_full_get_loc (&entry);
> gdb_printf ("%d bytes of memory at address %s changed from:",
> - to_print->u.mem.len,
> - print_core_address (arch, to_print->u.mem.addr));
> - for (int i = 0; i < to_print->u.mem.len; i++)
> + entry.u.mem.len,
> + print_core_address (arch, entry.u.mem.addr));
> + for (int i = 0; i < entry.u.mem.len; i++)
> gdb_printf (" %02x", b[i]);
> gdb_printf ("\n");
> break;
> }
> }
> - to_print = to_print->next;
> }
> }
>
> @@ -2880,11 +2657,6 @@ INIT_GDB_FILE (record_full)
> {
> struct cmd_list_element *c;
>
> - /* Init record_full_first. */
> - record_full_first.prev = NULL;
> - record_full_first.next = NULL;
> - record_full_first.type = record_full_end;
> -
> add_target (record_full_target_info, record_full_open);
> add_deprecated_target_alias (record_full_target_info, "record");
> add_target (record_full_core_target_info, record_full_open);
> diff --git a/gdb/record-full.h b/gdb/record-full.h
> index 51effe74560..c327d879a8a 100644
> --- a/gdb/record-full.h
> +++ b/gdb/record-full.h
> @@ -41,7 +41,6 @@ enum record_result
>
> extern int record_full_arch_list_add_reg (struct regcache *regcache, int
> num);
> extern int record_full_arch_list_add_mem (CORE_ADDR addr, int len);
> -extern int record_full_arch_list_add_end (void);
>
> /* Returns true if the process record target is open. */
> extern int record_full_is_used (void);
> diff --git a/gdb/riscv-tdep.c b/gdb/riscv-tdep.c
> index 6b5c9c02d46..f5b1f66844c 100644
> --- a/gdb/riscv-tdep.c
> +++ b/gdb/riscv-tdep.c
> @@ -5466,8 +5466,5 @@ riscv_process_record (struct gdbarch *gdbarch,
> struct regcache *regcache,
> if (res != RECORD_SUCCESS)
> return res;
>
> - if (record_full_arch_list_add_end ())
> - return -1;
> -
> return 0;
> }
> diff --git a/gdb/rs6000-tdep.c b/gdb/rs6000-tdep.c
> index e135df94a40..f964889a49f 100644
> --- a/gdb/rs6000-tdep.c
> +++ b/gdb/rs6000-tdep.c
> @@ -7138,8 +7138,6 @@ ppc_process_prefix_instruction (int insn_prefix, int
> insn_suffix,
> if (record_full_arch_list_add_reg (regcache, PPC_PC_REGNUM))
> return -1;
>
> - if (record_full_arch_list_add_end ())
> - return -1;
> return 0;
> }
>
> @@ -7447,8 +7445,6 @@ ppc_process_record (struct gdbarch *gdbarch,
> struct regcache *regcache,
>
> if (record_full_arch_list_add_reg (regcache, PPC_PC_REGNUM))
> return -1;
> - if (record_full_arch_list_add_end ())
> - return -1;
> return 0;
> }
>
> diff --git a/gdb/s390-linux-tdep.c b/gdb/s390-linux-tdep.c
> index 3cd6b359d13..6bea30f08dc 100644
> --- a/gdb/s390-linux-tdep.c
> +++ b/gdb/s390-linux-tdep.c
> @@ -910,9 +910,6 @@ s390_linux_record_signal (struct gdbarch *gdbarch,
> struct regcache *regcache,
> if (record_full_arch_list_add_mem (sp, sizeof_rt_sigframe))
> return -1;
>
> - if (record_full_arch_list_add_end ())
> - return -1;
> -
> return 0;
> }
>
> diff --git a/gdb/s390-tdep.c b/gdb/s390-tdep.c
> index f9d7bdd04e4..36ce659ea15 100644
> --- a/gdb/s390-tdep.c
> +++ b/gdb/s390-tdep.c
> @@ -7019,8 +7019,6 @@ s390_process_record (struct gdbarch *gdbarch,
> struct regcache *regcache,
>
> if (record_full_arch_list_add_reg (regcache, S390_PSWA_REGNUM))
> return -1;
> - if (record_full_arch_list_add_end ())
> - return -1;
> return 0;
> }
>
> --
> 2.53.0
>
Kind Regards,
Christina
Intel Deutschland GmbH
Registered Address: Dornacher Strasse 1, 85622 Feldkirchen, Germany
Tel: +49 89 991 430, www.intel.de
Managing Directors: Harry Demas, Jeffrey Schneiderman, Yin Chong Sorrell
Chairperson of the Supervisory Board: Nicole Lau
Registered Seat: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928
^ permalink raw reply [flat|nested] 19+ messages in thread
* Re: [PATCH v2 1/6] gdb/record: Refactor record history
2026-05-06 21:16 ` Schimpe, Christina
@ 2026-05-07 17:38 ` Guinevere Larsen
2026-05-11 15:23 ` Schimpe, Christina
0 siblings, 1 reply; 19+ messages in thread
From: Guinevere Larsen @ 2026-05-07 17:38 UTC (permalink / raw)
To: Schimpe, Christina, gdb-patches
On 5/6/26 6:16 PM, Schimpe, Christina wrote:
> Hi Guinevere,
>
> Thank you for working on this.
> I found two items that might be worth looking at in more detail, but
> apart from that it’s mostly minor nits. Please find my feedback below.
>
> I don’t have much experience with the record feature, so my review is
> a bit slow here. To fully understand this patch, I probably need more time,
> but I wanted to share the comments I already have. Sorry for chiming in
> so late. I’ll try again tomorrow, or by Friday at the latest.
Hi! Thank you for noting all the inconsistencies, I'll fix almost all of
them before pushing!
The one thing I don't think it's a good idea is to make the change from
record_full_list -> record_full_log in this commit... mostly because it
will introduce untold amounts of rebase conflicts. I'll introduce a
following commit to this series that will make that renaming, though :)
--
Cheers,
Guinevere Larsen
It/she
>> -----Original Message-----
>> From: Guinevere Larsen <guinevere@redhat.com>
>> Sent: Donnerstag, 23. April 2026 17:26
>> To: gdb-patches@sourceware.org
>> Cc: Guinevere Larsen <guinevere@redhat.com>
>> Subject: [PATCH v2 1/6] gdb/record: Refactor record history
>>
>> This is the first step in a large refactor in how GDB keeps execution
>> history. Rather than using a linked list where multiple entries can
>> describe a single instruction, the history will now be stored in an
>> std::deque, each instruction being one entry in the deque.
>>
>> The choice was initially to use an std::vector, but it would become
>> unwieldy because it needs all the memory to be consecutive, which is
>> hard for 200 thousand entries. Deque was picked because it was a nice
>> midpoint between vector (maximum cache cohesion) and linked list
>> (maximum ease of finding space to store more).
>>
>> Each instruction in memory will be now one record_full_instruction
>> entry, which for this commit just contains a vector of
>> record_full_entry for the effects of the instruction, and the data that
>> was stored in the record_full_end entry (that is, the instruction number
>> and the signal, if any).
>>
>> This change introduced a minimal performance improvement (what's
>> important is that it isn't a degradation) and a reduction in the total
>> memory footprint of roughly 20% if the entire history is used.
>> ---
>> gdb/aarch64-tdep.c | 2 -
>> gdb/amd64-linux-tdep.c | 3 -
>> gdb/arm-tdep.c | 2 -
>> gdb/i386-linux-tdep.c | 3 -
>> gdb/i386-tdep.c | 4 -
>> gdb/loongarch-tdep.c | 2 -
>> gdb/moxie-tdep.c | 2 -
>> gdb/ppc-linux-tdep.c | 3 -
>> gdb/record-full.c | 1180 ++++++++++++++++------------------------
>> gdb/record-full.h | 1 -
>> gdb/riscv-tdep.c | 3 -
>> gdb/rs6000-tdep.c | 4 -
>> gdb/s390-linux-tdep.c | 3 -
>> gdb/s390-tdep.c | 2 -
>> 14 files changed, 476 insertions(+), 738 deletions(-)
>>
>> diff --git a/gdb/aarch64-tdep.c b/gdb/aarch64-tdep.c
>> index 4befaa2720d..a532992b1d8 100644
>> --- a/gdb/aarch64-tdep.c
>> +++ b/gdb/aarch64-tdep.c
>> @@ -6210,8 +6210,6 @@ aarch64_process_record (struct gdbarch *gdbarch,
>> struct regcache *regcache,
>> aarch64_record.aarch64_mems[rec_no].len))
>> ret = -1;
>>
>> - if (record_full_arch_list_add_end ())
>> - ret = -1;
>> }
>>
>> deallocate_reg_mem (&aarch64_record);
>> diff --git a/gdb/amd64-linux-tdep.c b/gdb/amd64-linux-tdep.c
>> index a5ac26654cf..9b23db72bbe 100644
>> --- a/gdb/amd64-linux-tdep.c
>> +++ b/gdb/amd64-linux-tdep.c
>> @@ -1591,9 +1591,6 @@ amd64_linux_record_signal (struct gdbarch
>> *gdbarch,
>> + AMD64_LINUX_frame_size))
>> return -1;
>>
>> - if (record_full_arch_list_add_end ())
>> - return -1;
>> -
>> return 0;
>> }
>>
>> diff --git a/gdb/arm-tdep.c b/gdb/arm-tdep.c
>> index 08cce9dbad8..1ce0927f26b 100644
>> --- a/gdb/arm-tdep.c
>> +++ b/gdb/arm-tdep.c
>> @@ -14911,8 +14911,6 @@ arm_process_record (struct gdbarch *gdbarch,
>> struct regcache *regcache,
>> }
>> }
>>
>> - if (record_full_arch_list_add_end ())
>> - ret = -1;
>> }
>>
>>
>> diff --git a/gdb/i386-linux-tdep.c b/gdb/i386-linux-tdep.c
>> index 23aeccac9fc..4f33766fcdd 100644
>> --- a/gdb/i386-linux-tdep.c
>> +++ b/gdb/i386-linux-tdep.c
>> @@ -949,9 +949,6 @@ i386_linux_record_signal (struct gdbarch *gdbarch,
>> I386_LINUX_xstate +
>> I386_LINUX_frame_size))
>> return -1;
>>
>> - if (record_full_arch_list_add_end ())
>> - return -1;
>> -
>> return 0;
>> }
>>
>>
>> diff --git a/gdb/i386-tdep.c b/gdb/i386-tdep.c
>> index fa935b5fcdb..fee36b46a73 100644
>> --- a/gdb/i386-tdep.c
>> +++ b/gdb/i386-tdep.c
>> @@ -5201,8 +5201,6 @@ i386_record_vex (struct i386_record_s *ir, uint8_t
>> vex_w, uint8_t vex_r,
>> }
>>
>> record_full_arch_list_add_reg (ir->regcache, ir-
>>> regmap[X86_RECORD_REIP_REGNUM]);
>> - if (record_full_arch_list_add_end ())
>> - return -1;
>>
>> return 0;
>> }
>> @@ -8359,8 +8357,6 @@ Do you want to stop the program?"),
>>
>> /* In the future, maybe still need to deal with need_dasm. */
>> I386_RECORD_FULL_ARCH_LIST_ADD_REG (X86_RECORD_REIP_REGNUM);
>> - if (record_full_arch_list_add_end ())
>> - return -1;
>>
>> return 0;
>>
>> diff --git a/gdb/loongarch-tdep.c b/gdb/loongarch-tdep.c
>> index 225b1abb703..5ec6b2a48d0 100644
>> --- a/gdb/loongarch-tdep.c
>> +++ b/gdb/loongarch-tdep.c
>> @@ -2789,8 +2789,6 @@ loongarch_process_record (struct gdbarch
>> *gdbarch, struct regcache *regcache,
>> LOONGARCH_PC_REGNUM))
>> return -1;
>>
>> - if (record_full_arch_list_add_end ())
>> - return -1;
>> }
>>
>> return ret;
>> diff --git a/gdb/moxie-tdep.c b/gdb/moxie-tdep.c
>> index c8a04d21f59..2f8f0186488 100644
>> --- a/gdb/moxie-tdep.c
>> +++ b/gdb/moxie-tdep.c
>> @@ -1040,8 +1040,6 @@ moxie_process_record (struct gdbarch *gdbarch,
>> struct regcache *regcache,
>>
>> if (record_full_arch_list_add_reg (regcache, MOXIE_PC_REGNUM))
>> return -1;
>> - if (record_full_arch_list_add_end ())
>> - return -1;
>> return 0;
>> }
>>
>> diff --git a/gdb/ppc-linux-tdep.c b/gdb/ppc-linux-tdep.c
>> index 19698eaacbe..e2f53551709 100644
>> --- a/gdb/ppc-linux-tdep.c
>> +++ b/gdb/ppc-linux-tdep.c
>> @@ -1565,9 +1565,6 @@ ppc_linux_record_signal (struct gdbarch *gdbarch,
>> struct regcache *regcache,
>> if (record_full_arch_list_add_mem (sp, SIGNAL_FRAMESIZE +
>> sizeof_rt_sigframe))
>> return -1;
>>
>> - if (record_full_arch_list_add_end ())
>> - return -1;
>> -
>> return 0;
>> }
>>
>> diff --git a/gdb/record-full.c b/gdb/record-full.c
>> index 69d2c100e57..aac69cee17e 100644
>> --- a/gdb/record-full.c
>> +++ b/gdb/record-full.c
> I think we should include vector, optional and deque directly.
>
>> @@ -72,20 +72,17 @@
>> #define DEFAULT_RECORD_FULL_INSN_MAX_NUM 200000
>>
>> #define RECORD_FULL_IS_REPLAY \
>> - (record_full_list->next || ::execution_direction == EXEC_REVERSE)
>> + ( (record_full_next_insn != record_full_list.size ()) \
> Nit: No whitespace after the first bracket:
> => ((record_full_next_insn != record_full_list.size ()) \
>
>> + || ::execution_direction == EXEC_REVERSE)
>>
>> #define RECORD_FULL_FILE_MAGIC netorder32(0x20091016)
>>
>> /* These are the core structs of the process record functionality.
>>
>> A record_full_entry is a record of the value change of a register
>> - ("record_full_reg") or a part of memory ("record_full_mem"). And each
>> - instruction must have a struct record_full_entry ("record_full_end")
>> - that indicates that this is the last struct record_full_entry of this
>> - instruction.
>> -
>> - Each struct record_full_entry is linked to "record_full_list" by "prev"
>> - and "next" pointers. */
>> + ("record_full_reg") or a part of memory ("record_full_mem").
>> + These are saved on the record_full_instruction struct, which also
>> + contains some extra information, such as delivered signals. */
>>
>> struct record_full_mem_entry
>> {
>> @@ -112,47 +109,14 @@ struct record_full_reg_entry
>> } u;
>> };
>>
>> -struct record_full_end_entry
>> -{
>> - enum gdb_signal sigval;
>> - ULONGEST insn_num;
>> -};
>> -
>> enum record_full_type
>> {
>> - record_full_end = 0,
>> record_full_reg,
>> record_full_mem
>> };
>>
>> -/* This is the data structure that makes up the execution log.
>> -
>> - The execution log consists of a single linked list of entries
>> - of type "struct record_full_entry". It is doubly linked so that it
>> - can be traversed in either direction.
>> -
>> - The start of the list is anchored by a struct called
>> - "record_full_first". The pointer "record_full_list" either points
>> - to the last entry that was added to the list (in record mode), or to
>> - the next entry in the list that will be executed (in replay mode).
>> -
>> - Each list element (struct record_full_entry), in addition to next
>> - and prev pointers, consists of a union of three entry types: mem,
>> - reg, and end. A field called "type" determines which entry type is
>> - represented by a given list element.
>> -
>> - Each instruction that is added to the execution log is represented
>> - by a variable number of list elements ('entries'). The instruction
>> - will have one "reg" entry for each register that is changed by
>> - executing the instruction (including the PC in every case). It
>> - will also have one "mem" entry for each memory change. Finally,
>> - each instruction will have an "end" entry that separates it from
>> - the changes associated with the next instruction. */
>> -
>> struct record_full_entry
>> {
>> - struct record_full_entry *prev;
>> - struct record_full_entry *next;
>> enum record_full_type type;
>> union
>> {
>> @@ -160,11 +124,31 @@ struct record_full_entry
>> struct record_full_reg_entry reg;
>> /* mem */
>> struct record_full_mem_entry mem;
>> - /* end */
>> - struct record_full_end_entry end;
>> } u;
>> };
>>
>> +/* This is the main structure that comprises the execution log.
>> + Each instruction is comprised of:
>> + * The instruction number: How many instructions were recorded before
>> + this one;
>> + * sigval: Whether the inferior received a signal while the following
>> + instruction was being recorded;
>> + * effects: A list of record_full_entry structures, each of which
>> + describing one effect that the instruction has on the inferior.
>> +
>> + Note, the signal is stored in the previous instruction for historical
>> + reasons. This is how it was first implemented, and no one has gotten
>> + around to changing it yet. */
>> +
>> +struct record_full_instruction
>> +{
>> + /* This might be different from the index if
>> + we had to remove the first few instructions. */
>> + uint32_t insn_num;
>> + std::optional<gdb_signal> sigval;
>> + std::vector<record_full_entry> effects;
>> +};
>> +
>> /* If true, query if PREC cannot record memory
>> change of next instruction. */
>> bool record_full_memory_query = false;
>> @@ -181,27 +165,25 @@ static detached_regcache
>> *record_full_core_regbuf = NULL;
>> static std::vector<target_section> record_full_core_sections;
>> static struct record_full_core_buf_entry *record_full_core_buf_list = NULL;
>>
>> -/* The following variables are used for managing the linked list that
>> - represents the execution log.
>> +/* The following variables are used for managing the history of executed
>> + instructions from the inferior.
>>
>> - record_full_first is the anchor that holds down the beginning of
>> - the list.
>> + record_full_list contains all instructions that were fully executed and
>> + saved to the log, so that we can replay the execution.
>>
>> - record_full_list serves two functions:
>> - 1) In record mode, it anchors the end of the list.
>> - 2) In replay mode, it traverses the list and points to
>> - the next instruction that must be emulated.
>> + record_full_next_insn always points to the next instruction that would
>> + be executed if the inferior executes forward. In the special case when
>> + the inferior is not replaying, record_full_next_insn points past the
>> + end of the history.
>>
>> - record_full_arch_list_head and record_full_arch_list_tail are used
>> - to manage a separate list, which is used to build up the change
>> - elements of the currently executing instruction during record mode.
>> - When this instruction has been completely annotated in the "arch
>> - list", it will be appended to the main execution log. */
>> + record_full_incomplete_instruction holds a partial instruction, while
>> + the lower target is disassembling the instruction, or as partial xfers are
>> + happening. It is manipulated by the "arch list" functions for historical
>> + reasons. */
>>
>> -static struct record_full_entry record_full_first;
>> -static struct record_full_entry *record_full_list = &record_full_first;
>> -static struct record_full_entry *record_full_arch_list_head = NULL;
>> -static struct record_full_entry *record_full_arch_list_tail = NULL;
>> +static std::deque<record_full_instruction> record_full_list;
> Given that this is not a list anymore I wonder if we should better call this sth. like
> record_full_history or record_full_log or even simply recorded_instructions?
>
>> +static record_full_instruction record_full_incomplete_instruction;
>> +int record_full_next_insn;
>>
>> /* true ask user. false auto delete the last struct record_full_entry. */
>> static bool record_full_stop_at_limit = true;
>> @@ -361,6 +343,14 @@ record_full_target::kill ()
>> record_kill (this);
>> }
>>
>> +static void
>> +record_full_reset_incomplete ()
>> +{
>> + record_full_incomplete_instruction.effects.clear ();
>> + record_full_incomplete_instruction.sigval.reset ();
>> + record_full_incomplete_instruction.insn_num = 0;
>> +}
>> +
>> /* See record-full.h. */
>>
>> int
>> @@ -390,156 +380,120 @@ static struct cmd_list_element
>> *show_record_full_cmdlist;
>> /* Command list for "record full". */
>> static struct cmd_list_element *record_full_cmdlist;
>>
>> -static void record_full_goto_insn (struct record_full_entry *entry,
>> +static void record_full_goto_insn (size_t target_insn,
>> enum exec_direction_kind dir);
>>
>> -/* Alloc and free functions for record_full_reg, record_full_mem, and
>> - record_full_end entries. */
>> +/* Initialization and cleanup functions for record_full_reg and
>> + record_full_mem entries. */
>>
>> -/* Alloc a record_full_reg record entry. */
>> +/* Init a record_full_reg record entry. */
>>
>> -static inline struct record_full_entry *
>> -record_full_reg_alloc (struct regcache *regcache, int regnum)
>> +static inline struct record_full_entry
>> +record_full_reg_init (struct regcache *regcache, int regnum)
>> {
>> - struct record_full_entry *rec;
>> + struct record_full_entry rec;
>> struct gdbarch *gdbarch = regcache->arch ();
>>
>> - rec = XCNEW (struct record_full_entry);
>> - rec->type = record_full_reg;
>> - rec->u.reg.num = regnum;
>> - rec->u.reg.len = register_size (gdbarch, regnum);
>> - if (rec->u.reg.len > sizeof (rec->u.reg.u.buf))
>> - rec->u.reg.u.ptr = (gdb_byte *) xmalloc (rec->u.reg.len);
>> + rec.type = record_full_reg;
>> + rec.u.reg.num = regnum;
>> + rec.u.reg.len = register_size (gdbarch, regnum);
>> + if (rec.u.reg.len > sizeof (rec.u.reg.u.buf))
>> + rec.u.reg.u.ptr = (gdb_byte *) xmalloc (rec.u.reg.len);
>>
>> return rec;
>> }
>>
>> -/* Free a record_full_reg record entry. */
>> +/* Cleanup a record_full_reg record entry. */
>>
>> static inline void
>> -record_full_reg_release (struct record_full_entry *rec)
>> +record_full_reg_cleanup (struct record_full_entry rec)
>> {
>> - gdb_assert (rec->type == record_full_reg);
>> - if (rec->u.reg.len > sizeof (rec->u.reg.u.buf))
>> - xfree (rec->u.reg.u.ptr);
>> - xfree (rec);
>> + gdb_assert (rec.type == record_full_reg);
>> + if (rec.u.reg.len > sizeof (rec.u.reg.u.buf))
>> + xfree (rec.u.reg.u.ptr);
>> }
>>
>> -/* Alloc a record_full_mem record entry. */
>> +/* Init a record_full_mem record entry. */
>>
>> -static inline struct record_full_entry *
>> -record_full_mem_alloc (CORE_ADDR addr, int len)
>> +static inline struct record_full_entry
>> +record_full_mem_init (CORE_ADDR addr, int len)
>> {
>> - struct record_full_entry *rec;
>> + struct record_full_entry rec;
>>
>> - rec = XCNEW (struct record_full_entry);
>> - rec->type = record_full_mem;
>> - rec->u.mem.addr = addr;
>> - rec->u.mem.len = len;
>> - if (rec->u.mem.len > sizeof (rec->u.mem.u.buf))
>> - rec->u.mem.u.ptr = (gdb_byte *) xmalloc (len);
>> + rec.type = record_full_mem;
>> + rec.u.mem.addr = addr;
>> + rec.u.mem.len = len;
>> + if (rec.u.mem.len > sizeof (rec.u.mem.u.buf))
>> + rec.u.mem.u.ptr = (gdb_byte *) xmalloc (len);
>> + rec.u.mem.mem_entry_not_accessible = 0;
>>
>> return rec;
>> }
>>
>> -/* Free a record_full_mem record entry. */
>> +/* Cleanup a record_full_mem record entry. */
>>
>> static inline void
>> -record_full_mem_release (struct record_full_entry *rec)
>> -{
>> - gdb_assert (rec->type == record_full_mem);
>> - if (rec->u.mem.len > sizeof (rec->u.mem.u.buf))
>> - xfree (rec->u.mem.u.ptr);
>> - xfree (rec);
>> -}
>> -
>> -/* Alloc a record_full_end record entry. */
>> -
>> -static inline struct record_full_entry *
>> -record_full_end_alloc (void)
>> +record_full_mem_cleanup (struct record_full_entry rec)
>> {
>> - struct record_full_entry *rec;
>> -
>> - rec = XCNEW (struct record_full_entry);
>> - rec->type = record_full_end;
>> -
>> - return rec;
>> + gdb_assert (rec.type == record_full_mem);
>> + if (rec.u.mem.len > sizeof (rec.u.mem.u.buf))
>> + xfree (rec.u.mem.u.ptr);
>> }
>>
>> -/* Free a record_full_end record entry. */
>> +/* Free one record entry, any type. */
>>
>> static inline void
>> -record_full_end_release (struct record_full_entry *rec)
>> -{
>> - xfree (rec);
>> -}
>> -
>> -/* Free one record entry, any type.
>> - Return entry->type, in case caller wants to know. */
>> -
>> -static inline enum record_full_type
>> -record_full_entry_release (struct record_full_entry *rec)
>> +record_full_entry_cleanup (struct record_full_entry rec)
>> {
>> - enum record_full_type type = rec->type;
>>
>> - switch (type) {
>> + switch (rec.type) {
>> case record_full_reg:
>> - record_full_reg_release (rec);
>> + record_full_reg_cleanup (rec);
>> break;
>> case record_full_mem:
>> - record_full_mem_release (rec);
>> - break;
>> - case record_full_end:
>> - record_full_end_release (rec);
>> + record_full_mem_cleanup (rec);
>> break;
>> }
>> - return type;
>> }
>>
>> -/* Free all record entries in list pointed to by REC. */
>> -
>> static void
>> -record_full_list_release (struct record_full_entry *rec)
>> +record_full_reset_history ()
>> {
>> - if (!rec)
>> - return;
>> -
>> - while (rec->next)
>> - rec = rec->next;
>> + record_full_insn_num = 0;
>> + record_full_insn_count = 0;
>> + record_full_next_insn = 0;
>>
>> - while (rec->prev)
>> + for (auto &insn : record_full_list)
>> {
>> - rec = rec->prev;
>> - record_full_entry_release (rec->next);
>> + for (auto &entry : insn.effects)
>> + record_full_entry_cleanup (entry);
>> }
>>
>> - if (rec == &record_full_first)
>> - {
>> - record_full_insn_num = 0;
>> - record_full_first.next = NULL;
>> - }
>> - else
>> - record_full_entry_release (rec);
>> + record_full_list.clear ();
>> }
>>
>> -/* Free all record entries forward of the given list position. */
>> -
>> static void
>> -record_full_list_release_following (struct record_full_entry *rec)
>> +record_full_list_release_following (int index)
>> {
>> - struct record_full_entry *tmp = rec->next;
>> -
>> - rec->next = NULL;
>> - while (tmp)
>> + for (int i = record_full_list.size () - 1; i > index; i--)
>> {
>> - rec = tmp->next;
>> - if (record_full_entry_release (tmp) == record_full_end)
>> - {
>> - record_full_insn_num--;
>> - record_full_insn_count--;
>> - }
>> - tmp = rec;
>> + for (auto &entry : record_full_list[i].effects)
>> + record_full_entry_cleanup (entry);
>> + record_full_list.pop_back ();
>> }
>> + /* Set the next instruction to be past the end of the log so we
>> + start recording if the user moves forward again. */
>> + record_full_next_insn = index;
>> +}
>> +
>> +static void
>> +record_full_save_instruction ()
>> +{
>> + ++record_full_insn_count;
>> + record_full_incomplete_instruction.insn_num = record_full_insn_count;
>> + record_full_incomplete_instruction.effects.shrink_to_fit ();
>> + record_full_list.push_back (record_full_incomplete_instruction);
>> + record_full_next_insn++;
>> }
>>
>> /* Delete the first instruction from the beginning of the log, to make
>> @@ -550,52 +504,22 @@ record_full_list_release_following (struct
>> record_full_entry *rec)
>> static void
>> record_full_list_release_first (void)
>> {
>> - struct record_full_entry *tmp;
>> -
>> - if (!record_full_first.next)
>> + if (record_full_list.empty ())
>> return;
>>
>> - /* Loop until a record_full_end. */
>> - while (1)
>> - {
>> - /* Cut record_full_first.next out of the linked list. */
>> - tmp = record_full_first.next;
>> - record_full_first.next = tmp->next;
>> - tmp->next->prev = &record_full_first;
>> -
>> - /* tmp is now isolated, and can be deleted. */
>> - if (record_full_entry_release (tmp) == record_full_end)
>> - break; /* End loop at first record_full_end. */
>> + for (auto &entry : record_full_list[0].effects)
>> + record_full_entry_cleanup (entry);
>>
>> - if (!record_full_first.next)
>> - {
>> - gdb_assert (record_full_insn_num == 1);
>> - break; /* End loop when list is empty. */
>> - }
>> - }
>> + record_full_list.pop_front ();
>> + --record_full_next_insn;
>> }
>>
>> /* Add a struct record_full_entry to record_full_arch_list. */
>>
>> static void
>> -record_full_arch_list_add (struct record_full_entry *rec)
>> +record_full_arch_list_add (struct record_full_entry &rec)
>> {
>> - if (record_debug > 1)
>> - gdb_printf (gdb_stdlog,
>> - "Process record: record_full_arch_list_add %s.\n",
>> - host_address_to_string (rec));
>> -
>> - if (record_full_arch_list_tail)
>> - {
>> - record_full_arch_list_tail->next = rec;
>> - rec->prev = record_full_arch_list_tail;
>> - record_full_arch_list_tail = rec;
>> - }
>> - else
>> - {
>> - record_full_arch_list_head = rec;
>> - record_full_arch_list_tail = rec;
>> - }
>> + record_full_incomplete_instruction.effects.push_back (rec);
>> }
>>
>> /* Return the value storage location of a record entry. */
>> @@ -613,7 +537,6 @@ record_full_get_loc (struct record_full_entry *rec)
>> return rec->u.reg.u.ptr;
>> else
>> return rec->u.reg.u.buf;
>> - case record_full_end:
>> default:
>> gdb_assert_not_reached ("unexpected record_full_entry type");
>> return NULL;
>> @@ -625,7 +548,7 @@ record_full_get_loc (struct record_full_entry *rec)
>> int
>> record_full_arch_list_add_reg (struct regcache *regcache, int regnum)
>> {
>> - struct record_full_entry *rec;
>> + struct record_full_entry rec;
> I think we can omit the struct keyword here (there are some more occurrences in this patch).
>
>> if (record_debug > 1)
>> gdb_printf (gdb_stdlog,
>> @@ -633,9 +556,9 @@ record_full_arch_list_add_reg (struct regcache
>> *regcache, int regnum)
>> "record list.\n",
>> regnum);
>>
>> - rec = record_full_reg_alloc (regcache, regnum);
>> + rec = record_full_reg_init (regcache, regnum);
>>
>> - regcache->cooked_read (regnum, record_full_get_loc (rec));
>> + regcache->cooked_read (regnum, record_full_get_loc (&rec));
>>
>> record_full_arch_list_add (rec);
>>
>> @@ -648,7 +571,7 @@ record_full_arch_list_add_reg (struct regcache
>> *regcache, int regnum)
>> int
>> record_full_arch_list_add_mem (CORE_ADDR addr, int len)
>> {
>> - struct record_full_entry *rec;
>> + struct record_full_entry rec;
>>
>> if (record_debug > 1)
>> gdb_printf (gdb_stdlog,
>> @@ -659,12 +582,12 @@ record_full_arch_list_add_mem (CORE_ADDR addr,
>> int len)
>> if (!addr) /* FIXME: Why? Some arch must permit it... */
>> return 0;
>>
>> - rec = record_full_mem_alloc (addr, len);
>> + rec = record_full_mem_init (addr, len);
>>
>> if (record_read_memory (current_inferior ()->arch (), addr,
>> - record_full_get_loc (rec), len))
>> + record_full_get_loc (&rec), len))
>> {
>> - record_full_mem_release (rec);
>> + record_full_mem_cleanup (rec);
>> return -1;
>> }
>>
>> @@ -673,27 +596,6 @@ record_full_arch_list_add_mem (CORE_ADDR addr,
>> int len)
>> return 0;
>> }
>>
>> -/* Add a record_full_end type struct record_full_entry to
>> - record_full_arch_list. */
>> -
>> -int
>> -record_full_arch_list_add_end (void)
>> -{
>> - struct record_full_entry *rec;
>> -
>> - if (record_debug > 1)
>> - gdb_printf (gdb_stdlog,
>> - "Process record: add end to arch list.\n");
>> -
>> - rec = record_full_end_alloc ();
>> - rec->u.end.sigval = GDB_SIGNAL_0;
>> - rec->u.end.insn_num = ++record_full_insn_count;
>> -
>> - record_full_arch_list_add (rec);
>> -
>> - return 0;
>> -}
>> -
>> static void
>> record_full_check_insn_num (void)
>> {
>> @@ -725,8 +627,7 @@ record_full_message (struct regcache *regcache,
>> enum gdb_signal signal)
>>
>> try
>> {
>> - record_full_arch_list_head = NULL;
>> - record_full_arch_list_tail = NULL;
>> + record_full_reset_incomplete ();
>>
>> /* Check record_full_insn_num. */
>> record_full_check_insn_num ();
>> @@ -746,20 +647,16 @@ record_full_message (struct regcache *regcache,
>> enum gdb_signal signal)
>> the user says something different, like "deliver this signal"
>> during the replay mode).
>>
>> - User should understand that nothing he does during the replay
>> - mode will change the behavior of the child. If he tries,
>> + User should understand that nothing they do during the replay
>> + mode will change the behavior of the child. If they try,
>> then that is a user error.
>>
>> But we should still deliver the signal to gdb during the replay,
>> if we delivered it during the recording. Therefore we should
>> record the signal during record_full_wait, not
>> record_full_resume. */
>> - if (record_full_list != &record_full_first) /* FIXME better way
>> - to check */
>> - {
>> - gdb_assert (record_full_list->type == record_full_end);
>> - record_full_list->u.end.sigval = signal;
>> - }
>> + if (signal != GDB_SIGNAL_0)
>> + record_full_list[record_full_next_insn - 1].sigval = signal;
>>
>> if (signal == GDB_SIGNAL_0
>> || !gdbarch_process_record_signal_p (gdbarch))
>> @@ -778,13 +675,11 @@ record_full_message (struct regcache *regcache,
>> enum gdb_signal signal)
>> }
>> catch (const gdb_exception &ex)
>> {
>> - record_full_list_release (record_full_arch_list_tail);
>> + record_full_reset_incomplete ();
>> throw;
>> }
>>
>> - record_full_list->next = record_full_arch_list_head;
>> - record_full_arch_list_head->prev = record_full_list;
>> - record_full_list = record_full_arch_list_tail;
>> + record_full_save_instruction ();
>>
>> if (record_full_insn_num == record_full_insn_max_num)
>> record_full_list_release_first ();
>> @@ -829,9 +724,9 @@ static enum target_stop_reason
>> record_full_stop_reason
>> entries and memory entries, followed by an 'end' entry. */
>>
>> static inline void
>> -record_full_exec_insn (struct regcache *regcache,
>> - struct gdbarch *gdbarch,
>> - struct record_full_entry *entry)
>> +record_full_exec_entry (struct regcache *regcache,
>> + struct gdbarch *gdbarch,
>> + struct record_full_entry *entry)
> Nit: omit struct keywords
> And there are some more places in this series/patch, but I will stop commenting
> now on all of them.
>
>> {
>> switch (entry->type)
>> {
>> @@ -909,6 +804,15 @@ record_full_exec_insn (struct regcache *regcache,
>> }
>> }
>>
>> +static inline void
>> +record_full_exec_insn (struct regcache *regcache,
>> + struct gdbarch *gdbarch,
>> + record_full_instruction &insn)
>> +{
>> + for (auto &entry : insn.effects)
>> + record_full_exec_entry (regcache, gdbarch, &entry);
>> +}
>> +
>> static void record_full_restore (struct bfd &cbfd);
>>
>> /* Asynchronous signal handle registered as event loop source for when
>> @@ -983,10 +887,7 @@ record_full_open (const char *args, int from_tty)
>> record_preopen ();
>>
>> /* Reset */
>> - record_full_insn_num = 0;
>> - record_full_insn_count = 0;
>> - record_full_list = &record_full_first;
>> - record_full_list->next = NULL;
>> + record_full_reset_history ();
>>
>> bfd *cbfd = get_inferior_core_bfd (current_inferior ());
>> if (cbfd != nullptr)
>> @@ -1014,7 +915,7 @@ record_full_base_target::close ()
>> if (record_debug)
>> gdb_printf (gdb_stdlog, "Process record: record_full_close\n");
>>
>> - record_full_list_release (record_full_list);
>> + record_full_reset_history ();
>>
>> /* Release record_full_core_regbuf. */
>> if (record_full_core_regbuf)
>> @@ -1313,7 +1214,6 @@ record_full_wait_1 (struct target_ops *ops,
>> struct gdbarch *gdbarch = regcache->arch ();
>> const address_space *aspace = current_inferior ()->aspace.get ();
>> int continue_flag = 1;
>> - int first_record_full_end = 1;
>>
>> try
>> {
>> @@ -1322,7 +1222,6 @@ record_full_wait_1 (struct target_ops *ops,
>> record_full_stop_reason = TARGET_STOPPED_BY_NO_REASON;
>> status->set_stopped (GDB_SIGNAL_0);
>>
>> - /* Check breakpoint when forward execute. */
>> if (execution_direction == EXEC_FORWARD)
>> {
>> tmp_pc = regcache_read_pc (regcache);
>> @@ -1330,8 +1229,7 @@ record_full_wait_1 (struct target_ops *ops,
>>
>> &record_full_stop_reason))
>> {
>> if (record_debug)
>> - gdb_printf (gdb_stdlog,
>> - "Process record: break at %s.\n",
>> + gdb_printf (gdb_stdlog, "Process record: break at %s.\n",
>> paddress (gdbarch, tmp_pc));
>> goto replay_out;
>> }
>> @@ -1344,10 +1242,10 @@ record_full_wait_1 (struct target_ops *ops,
>> the signal. */
>> target_terminal::ours ();
>>
>> - /* In EXEC_FORWARD mode, record_full_list points to the tail of prev
>> - instruction. */
>> - if (execution_direction == EXEC_FORWARD && record_full_list->next)
>> - record_full_list = record_full_list->next;
>> + /* In EXEC_FORWARD mode, record_full_next_insn is the next
>> + instruction to be executed. */
>> + if (execution_direction == EXEC_REVERSE)
>> + record_full_next_insn--;
>>
>> /* Loop over the record_full_list, looking for the next place to
>> stop. */
>> @@ -1355,108 +1253,92 @@ record_full_wait_1 (struct target_ops *ops,
>> {
>> /* Check for beginning and end of log. */
>> if (execution_direction == EXEC_REVERSE
>> - && record_full_list == &record_full_first)
>> + && record_full_next_insn < 0)
>> {
>> /* Hit beginning of record log in reverse. */
>> status->set_no_history ();
>> + record_full_next_insn = 0;
>> break;
>> }
>> if (execution_direction != EXEC_REVERSE
>> - && !record_full_list->next)
>> + && record_full_next_insn == record_full_list.size ())
>> {
>> /* Hit end of record log going forward. */
>> status->set_no_history ();
>> break;
>> }
>>
>> - record_full_exec_insn (regcache, gdbarch, record_full_list);
>> + record_full_exec_insn
>> + (regcache, gdbarch,
>> + record_full_list[record_full_next_insn]);
>>
>> - if (record_full_list->type == record_full_end)
>> + /* step */
>> + if (record_full_resume_step)
>> {
>> if (record_debug > 1)
>> - gdb_printf
>> - (gdb_stdlog,
>> - "Process record: record_full_end %s to "
>> - "inferior.\n",
>> - host_address_to_string (record_full_list));
>> -
>> - if (first_record_full_end
>> - && execution_direction == EXEC_REVERSE)
>> - {
>> - /* When reverse execute, the first
>> - record_full_end is the part of current
>> - instruction. */
>> - first_record_full_end = 0;
>> - }
>> - else
>> - {
>> - /* In EXEC_REVERSE mode, this is the
>> - record_full_end of prev instruction. In
>> - EXEC_FORWARD mode, this is the
>> - record_full_end of current instruction. */
>> - /* step */
>> - if (record_full_resume_step)
>> - {
>> - if (record_debug > 1)
>> - gdb_printf (gdb_stdlog,
>> - "Process record: step.\n");
>> - continue_flag = 0;
>> - }
>> -
>> - /* check breakpoint */
>> - tmp_pc = regcache_read_pc (regcache);
>> - if (record_check_stopped_by_breakpoint
>> - (aspace, tmp_pc, &record_full_stop_reason))
>> - {
>> - if (record_debug)
>> - gdb_printf (gdb_stdlog,
>> - "Process record: break "
>> - "at %s.\n",
>> - paddress (gdbarch, tmp_pc));
>> + gdb_printf (gdb_stdlog,
>> + "Process record: step.\n");
>> + continue_flag = 0;
>> + }
>>
>> - continue_flag = 0;
>> - }
>> + /* check breakpoint */
>> + tmp_pc = regcache_read_pc (regcache);
>> + if (record_check_stopped_by_breakpoint
>> + (aspace, tmp_pc, &record_full_stop_reason))
>> + {
>> + if (record_debug)
>> + gdb_printf (gdb_stdlog,
>> + "Process record: break "
>> + "at %s.\n",
>> + paddress (gdbarch, tmp_pc));
>>
>> - if (record_full_stop_reason
>> - == TARGET_STOPPED_BY_WATCHPOINT)
>> - {
>> - if (record_debug)
>> - gdb_printf (gdb_stdlog,
>> - "Process record: hit hw "
>> - "watchpoint.\n");
>> - continue_flag = 0;
>> - }
>> - /* Check target signal */
>> - if (record_full_list->u.end.sigval != GDB_SIGNAL_0)
>> - /* FIXME: better way to check */
>> - continue_flag = 0;
>> - }
>> + continue_flag = 0;
>> }
>>
>> - if (continue_flag)
>> + if (record_full_stop_reason
>> + == TARGET_STOPPED_BY_WATCHPOINT)
>> {
>> - if (execution_direction == EXEC_REVERSE)
>> - {
>> - if (record_full_list->prev)
>> - record_full_list = record_full_list->prev;
>> - }
>> - else
>> - {
>> - if (record_full_list->next)
>> - record_full_list = record_full_list->next;
>> - }
>> + if (record_debug)
>> + gdb_printf (gdb_stdlog,
>> + "Process record: hit hw "
>> + "watchpoint.\n");
>> + continue_flag = 0;
>> }
>> + if (record_full_list[record_full_next_insn].sigval.has_value ())
>> + continue_flag = 0;
>> +
>> + if (execution_direction == EXEC_REVERSE)
>> + record_full_next_insn--;
>> + else
>> + record_full_next_insn++;
>> }
>> while (continue_flag);
>>
>> + if (record_full_next_insn < 0)
>> + {
>> + gdb_assert (execution_direction == EXEC_REVERSE);
>> + record_full_next_insn = 0;
>> + }
>> + else if (record_full_next_insn > record_full_list.size ())
>> + {
>> + gdb_assert (execution_direction == EXEC_FORWARD);
>> + record_full_next_insn = record_full_list.size ();
>> + }
>> + /* Reset the current instruciton to point to the one to be replayed
> Nit: instruction
>
>> + moving forward. */
>> + else if (execution_direction == EXEC_REVERSE)
>> + record_full_next_insn++;
>> +
>> replay_out:
>> if (status->kind () == TARGET_WAITKIND_STOPPED)
>> {
>> + int insn = (execution_direction == EXEC_FORWARD)
>> + ? record_full_next_insn - 1 : record_full_next_insn;
>> if (record_full_get_sig)
>> status->set_stopped (GDB_SIGNAL_INT);
>> - else if (record_full_list->u.end.sigval != GDB_SIGNAL_0)
>> - /* FIXME: better way to check */
>> - status->set_stopped (record_full_list->u.end.sigval);
>> + else if (record_full_list[insn].sigval.has_value ())
>> + status->set_stopped
>> + (record_full_list[insn].sigval.value ());
>> else
>> status->set_stopped (GDB_SIGNAL_TRAP);
>> }
>> @@ -1464,12 +1346,9 @@ record_full_wait_1 (struct target_ops *ops,
>> catch (const gdb_exception &ex)
>> {
>> if (execution_direction == EXEC_REVERSE)
>> - {
>> - if (record_full_list->next)
>> - record_full_list = record_full_list->next;
>> - }
>> + record_full_next_insn++;
>> else
>> - record_full_list = record_full_list->prev;
>> + record_full_next_insn--;
>>
>> throw;
>> }
>> @@ -1557,8 +1436,7 @@ record_full_registers_change (struct regcache
>> *regcache, int regnum)
>> /* Check record_full_insn_num. */
>> record_full_check_insn_num ();
>>
>> - record_full_arch_list_head = NULL;
>> - record_full_arch_list_tail = NULL;
>> + record_full_reset_incomplete ();
>>
>> if (regnum < 0)
>> {
>> @@ -1568,7 +1446,7 @@ record_full_registers_change (struct regcache
>> *regcache, int regnum)
>> {
>> if (record_full_arch_list_add_reg (regcache, i))
>> {
>> - record_full_list_release (record_full_arch_list_tail);
>> + record_full_reset_incomplete ();
>> error (_("Process record: failed to record execution log."));
>> }
>> }
>> @@ -1577,18 +1455,11 @@ record_full_registers_change (struct regcache
>> *regcache, int regnum)
>> {
>> if (record_full_arch_list_add_reg (regcache, regnum))
>> {
>> - record_full_list_release (record_full_arch_list_tail);
>> + record_full_reset_incomplete ();
>> error (_("Process record: failed to record execution log."));
>> }
>> }
>> - if (record_full_arch_list_add_end ())
>> - {
>> - record_full_list_release (record_full_arch_list_tail);
>> - error (_("Process record: failed to record execution log."));
>> - }
>> - record_full_list->next = record_full_arch_list_head;
>> - record_full_arch_list_head->prev = record_full_list;
>> - record_full_list = record_full_arch_list_tail;
>> + record_full_save_instruction ();
>>
>> if (record_full_insn_num == record_full_insn_max_num)
>> record_full_list_release_first ();
>> @@ -1607,7 +1478,7 @@ record_full_target::store_registers (struct
>> regcache *regcache, int regno)
>> {
>> int n;
>>
>> - /* Let user choose if he wants to write register or not. */
>> + /* Let user choose if they want to write register or not. */
>> if (regno < 0)
>> n =
>> query (_("Because GDB is in replay mode, changing the "
>> @@ -1642,7 +1513,7 @@ record_full_target::store_registers (struct
>> regcache *regcache, int regno)
>> }
>>
>> /* Destroy the record from here forward. */
>> - record_full_list_release_following (record_full_list);
>> + record_full_list_release_following (record_full_next_insn);
>> }
>>
>> record_full_registers_change (regcache, regno);
>> @@ -1675,36 +1546,24 @@ record_full_target::xfer_partial (enum
>> target_object object,
>> error (_("Process record canceled the operation."));
>>
>> /* Destroy the record from here forward. */
>> - record_full_list_release_following (record_full_list);
>> + record_full_list_release_following (record_full_next_insn);
>> }
>>
>> /* Check record_full_insn_num */
>> record_full_check_insn_num ();
>>
>> /* Record registers change to list as an instruction. */
>> - record_full_arch_list_head = NULL;
>> - record_full_arch_list_tail = NULL;
>> + record_full_reset_incomplete ();
>> if (record_full_arch_list_add_mem (offset, len))
>> {
>> - record_full_list_release (record_full_arch_list_tail);
>> + record_full_reset_incomplete ();
>> if (record_debug)
>> gdb_printf (gdb_stdlog,
>> "Process record: failed to record "
>> "execution log.");
>> return TARGET_XFER_E_IO;
>> }
>> - if (record_full_arch_list_add_end ())
>> - {
>> - record_full_list_release (record_full_arch_list_tail);
>> - if (record_debug)
>> - gdb_printf (gdb_stdlog,
>> - "Process record: failed to record "
>> - "execution log.");
>> - return TARGET_XFER_E_IO;
>> - }
>> - record_full_list->next = record_full_arch_list_head;
>> - record_full_arch_list_head->prev = record_full_list;
>> - record_full_list = record_full_arch_list_tail;
>> + record_full_save_instruction ();
>>
>> if (record_full_insn_num == record_full_insn_max_num)
>> record_full_list_release_first ();
>> @@ -1866,8 +1725,7 @@ record_full_base_target::get_bookmark (const char
>> *args, int from_tty)
>> char *ret = NULL;
>>
>> /* Return stringified form of instruction count. */
>> - if (record_full_list && record_full_list->type == record_full_end)
>> - ret = xstrdup (pulongest (record_full_list->u.end.insn_num));
>> + ret = xstrdup (pulongest (record_full_list[record_full_next_insn].insn_num));
> I think we can get here with an empty record_full_list - in case we are in recording mode,
> no instructions have been logged and this function is called:
>
> ~~~
> (gdb) info record
> Active record target: record-full
> Record mode:
> No instructions have been logged.
> Max logged instructions is 200000.
> (gdb) bookmark
>
> Thread 1 "gdb-up" hit Breakpoint 1, record_full_base_target::get_bookmark (this=0x555558392900 <record_full_ops>, args=0x0, from_tty=1) at /tmp/record-full.c:1774
> 1774 char *ret = NULL;
> (gdb) p record_full_next_insn
> $1 = 0
> (gdb) p record_full_list.empty ()
> $2 = true
> ~~~
>
>> if (record_debug)
>> {
>> @@ -1923,30 +1781,22 @@ record_full_base_target::record_method (ptid_t
>> ptid)
>> void
>> record_full_base_target::info_record ()
>> {
>> - struct record_full_entry *p;
>> -
>> if (RECORD_FULL_IS_REPLAY)
>> gdb_printf (_("Replay mode:\n"));
>> else
>> gdb_printf (_("Record mode:\n"));
>>
>> - /* Find entry for first actual instruction in the log. */
>> - for (p = record_full_first.next;
>> - p != NULL && p->type != record_full_end;
>> - p = p->next)
>> - ;
>> -
>> /* Do we have a log at all? */
>> - if (p != NULL && p->type == record_full_end)
>> + if (!record_full_list.empty ())
>> {
>> /* Display instruction number for first instruction in the log. */
>> - gdb_printf (_("Lowest recorded instruction number is %s.\n"),
>> - pulongest (p->u.end.insn_num));
>> + gdb_printf (_("Lowest recorded instruction number is %u.\n"),
>> + record_full_list[0].insn_num);
>>
>> /* If in replay mode, display where we are in the log. */
>> if (RECORD_FULL_IS_REPLAY)
>> - gdb_printf (_("Current instruction number is %s.\n"),
>> - pulongest (record_full_list->u.end.insn_num));
>> + gdb_printf (_("Current instruction number is %u.\n"),
>> + record_full_list[record_full_next_insn].insn_num);
>>
>> /* Display instruction number for last instruction in the log. */
>> gdb_printf (_("Highest recorded instruction number is %s.\n"),
>> @@ -1975,7 +1825,7 @@ record_full_base_target::supports_delete_record ()
>> void
>> record_full_base_target::delete_record ()
>> {
>> - record_full_list_release_following (record_full_list);
>> + record_full_reset_history ();
>> }
>>
>> /* The "record_is_replaying" target method. */
>> @@ -2001,23 +1851,23 @@ record_full_base_target::record_will_replay
>> (ptid_t ptid, int dir)
>> /* Go to a specific entry. */
>>
>> static void
>> -record_full_goto_entry (struct record_full_entry *p)
>> +record_full_goto_entry (size_t target_insn)
>> {
>> - if (p == NULL)
>> + if (target_insn >= record_full_list.size ())
>> error (_("Target insn not found."));
>> - else if (p == record_full_list)
>> + else if (target_insn == record_full_next_insn)
>> error (_("Already at target insn."));
>> - else if (p->u.end.insn_num > record_full_list->u.end.insn_num)
>> + else if (target_insn > record_full_next_insn)
>> {
>> gdb_printf (_("Go forward to insn number %s\n"),
>> - pulongest (p->u.end.insn_num));
>> - record_full_goto_insn (p, EXEC_FORWARD);
>> + pulongest (record_full_list[target_insn].insn_num));
>> + record_full_goto_insn (target_insn, EXEC_FORWARD);
>> }
>> else
>> {
>> gdb_printf (_("Go backward to insn number %s\n"),
>> - pulongest (p->u.end.insn_num));
>> - record_full_goto_insn (p, EXEC_REVERSE);
>> + pulongest (target_insn));
>> + record_full_goto_insn (target_insn, EXEC_REVERSE);
>> }
>>
>> registers_changed ();
>> @@ -2033,13 +1883,7 @@ record_full_goto_entry (struct record_full_entry
>> *p)
>> void
>> record_full_base_target::goto_record_begin ()
>> {
>> - struct record_full_entry *p = NULL;
>> -
>> - for (p = &record_full_first; p != NULL; p = p->next)
>> - if (p->type == record_full_end)
>> - break;
>> -
>> - record_full_goto_entry (p);
>> + record_full_goto_entry (0);
>> }
>>
>> /* The "goto_record_end" target method. */
>> @@ -2047,15 +1891,7 @@ record_full_base_target::goto_record_begin ()
>> void
>> record_full_base_target::goto_record_end ()
>> {
>> - struct record_full_entry *p = NULL;
>> -
>> - for (p = record_full_list; p->next != NULL; p = p->next)
>> - ;
>> - for (; p!= NULL; p = p->prev)
>> - if (p->type == record_full_end)
>> - break;
>> -
>> - record_full_goto_entry (p);
>> + record_full_goto_entry (record_full_list.size () -1);
> Nit: whitespace before 1 => "record_full_list.size () - 1"
>
> And in case the record_full_list is empty, won't we call
> record_full_goto_entry with an invalid value for target_insn ?
>
>> }
>>
>> /* The "goto_record" target method. */
>> @@ -2063,13 +1899,7 @@ record_full_base_target::goto_record_end ()
>> void
>> record_full_base_target::goto_record (ULONGEST target_insn)
>> {
>> - struct record_full_entry *p = NULL;
>> -
>> - for (p = &record_full_first; p != NULL; p = p->next)
>> - if (p->type == record_full_end && p->u.end.insn_num == target_insn)
>> - break;
>> -
>> - record_full_goto_entry (p);
>> + record_full_goto_entry (target_insn);
>> }
>>
>> /* The "record_stop_replaying" target method. */
>> @@ -2339,19 +2169,96 @@ netorder32 (uint32_t input)
>> return ret;
>> }
>>
>> +static void
>> +record_full_read_entry_from_bfd (bfd *cbfd, asection *osec, int *bfd_offset)
>> +{
>> + uint8_t rectype;
>> + uint32_t regnum, len;
>> + uint64_t addr;
>> + regcache *cache = get_thread_regcache (inferior_thread ());
>> +
>> + bfdcore_read (cbfd, osec, &rectype, sizeof (rectype), bfd_offset);
>> + switch (rectype)
>> + {
>> + case record_full_reg: /* reg */
>> + {
>> + /* Get register number to regnum. */
>> + bfdcore_read (cbfd, osec, ®num, sizeof (regnum), bfd_offset);
>> + regnum = netorder32 (regnum);
>> +
>> + record_full_entry rec;
>> +
>> + rec = record_full_reg_init (cache, regnum);
>> +
>> + /* Get val. */
>> + bfdcore_read (cbfd, osec, record_full_get_loc (&rec),
>> + rec.u.reg.len, bfd_offset);
>> +
>> + if (record_debug)
>> + gdb_printf (gdb_stdlog,
>> + " Reading register %d (1 "
>> + "plus %lu plus %d bytes)\n",
>> + rec.u.reg.num,
>> + (unsigned long) sizeof (regnum),
>> + rec.u.reg.len);
>> +
>> + record_full_arch_list_add (rec);
>> + break;
>> + }
>> +
>> + case record_full_mem: /* mem */
>> + {
>> + /* Get len. */
>> + bfdcore_read (cbfd, osec, &len, sizeof (len), bfd_offset);
>> + len = netorder32 (len);
>> +
>> + /* Get addr. */
>> + bfdcore_read (cbfd, osec, &addr, sizeof (addr),
>> + bfd_offset);
>> + addr = netorder64 (addr);
>> +
>> + record_full_entry rec;
>> + rec = record_full_mem_init (addr, len);
>> +
>> + /* Get val. */
>> + bfdcore_read (cbfd, osec, record_full_get_loc (&rec), len,
>> + bfd_offset);
>> +
>> + if (record_debug)
>> + gdb_printf (gdb_stdlog,
>> + " Reading memory %s (1 plus "
>> + "%lu plus %lu plus %d bytes)\n",
>> + paddress (get_current_arch (),
>> + rec.u.mem.addr),
>> + (unsigned long) sizeof (addr),
>> + (unsigned long) sizeof (len),
>> + len);
>> +
>> + record_full_arch_list_add (rec);
>> + break;
>> + }
>> +
>> + default:
>> + error (_("Bad entry type %d, offset %d of %lu in core file %ps."),
>> + rectype, *bfd_offset, bfd_section_size (osec),
>> + styled_string (file_name_style.style (),
>> + bfd_get_filename (cbfd)));
>> + break;
>> + }
>> +}
>> +
>> /* Restore the execution log from core file CBFD. */
>>
>> static void
>> record_full_restore (struct bfd &cbfd)
>> {
>> uint32_t magic;
>> - struct record_full_entry *rec;
>> asection *osec;
>> uint32_t osec_size;
>> int bfd_offset = 0;
>>
>> /* "record_full_restore" can only be called when record list is empty. */
>> - gdb_assert (record_full_first.next == NULL);
>> + gdb_assert (record_full_list.empty ());
>>
>> if (record_debug)
>> gdb_printf (gdb_stdlog, "Restoring recording from core file.\n");
>> @@ -2379,124 +2286,47 @@ record_full_restore (struct bfd &cbfd)
>> "RECORD_FULL_FILE_MAGIC (0x%s)\n",
>> phex_nz (netorder32 (magic), 4));
>>
>> - /* Restore the entries in recfd into record_full_arch_list_head and
>> - record_full_arch_list_tail. */
>> - record_full_arch_list_head = NULL;
>> - record_full_arch_list_tail = NULL;
>> record_full_insn_num = 0;
>>
>> try
>> {
>> - regcache *regcache = get_thread_regcache (inferior_thread ());
>> -
>> - while (1)
>> + while (bfd_offset < osec_size)
>> {
>> - uint8_t rectype;
>> - uint32_t regnum, len, signal, count;
>> - uint64_t addr;
>> -
>> - /* We are finished when offset reaches osec_size. */
>> - if (bfd_offset >= osec_size)
>> - break;
>> - bfdcore_read (&cbfd, osec, &rectype, sizeof (rectype), &bfd_offset);
>> -
>> - switch (rectype)
>> + record_full_reset_incomplete ();
>> + uint32_t eff_count = 0;
>> + uint8_t sigval;
>> + uint32_t insn_num;
>> +
>> + /* First read the generic information for an instruction. */
>> + bfdcore_read (&cbfd, osec, &sigval, sizeof (uint8_t), &bfd_offset);
>> + bfdcore_read (&cbfd, osec, &eff_count, sizeof (uint32_t),
>> + &bfd_offset);
>> + bfdcore_read (&cbfd, osec, &insn_num, sizeof (uint32_t),
>> + &bfd_offset);
>> +
>> + record_full_incomplete_instruction.insn_num = netorder32
>> (insn_num);
>> + if (sigval != GDB_SIGNAL_0)
>> + record_full_incomplete_instruction.sigval = (gdb_signal) sigval;
>> +
>> + eff_count = netorder32 (eff_count);
>> +
>> + /* This deals with all the side effects. */
>> + while (eff_count > 0)
>> {
> There is one space too much indent.
>
>> - case record_full_reg: /* reg */
>> - /* Get register number to regnum. */
>> - bfdcore_read (&cbfd, osec, ®num, sizeof (regnum),
>> - &bfd_offset);
>> - regnum = netorder32 (regnum);
>> -
>> - rec = record_full_reg_alloc (regcache, regnum);
>> -
>> - /* Get val. */
>> - bfdcore_read (&cbfd, osec, record_full_get_loc (rec),
>> - rec->u.reg.len, &bfd_offset);
>> -
>> - if (record_debug)
>> - gdb_printf (gdb_stdlog,
>> - " Reading register %d (1 "
>> - "plus %lu plus %d bytes)\n",
>> - rec->u.reg.num,
>> - (unsigned long) sizeof (regnum),
>> - rec->u.reg.len);
>> - break;
>> + eff_count--;
>>
>> - case record_full_mem: /* mem */
>> - /* Get len. */
>> - bfdcore_read (&cbfd, osec, &len, sizeof (len), &bfd_offset);
>> - len = netorder32 (len);
>> -
>> - /* Get addr. */
>> - bfdcore_read (&cbfd, osec, &addr, sizeof (addr), &bfd_offset);
>> - addr = netorder64 (addr);
>> -
>> - rec = record_full_mem_alloc (addr, len);
>> -
>> - /* Get val. */
>> - bfdcore_read (&cbfd, osec, record_full_get_loc (rec),
>> - rec->u.mem.len, &bfd_offset);
>> -
>> - if (record_debug)
>> - gdb_printf (gdb_stdlog,
>> - " Reading memory %s (1 plus "
>> - "%lu plus %lu plus %d bytes)\n",
>> - paddress (get_current_arch (),
>> - rec->u.mem.addr),
>> - (unsigned long) sizeof (addr),
>> - (unsigned long) sizeof (len),
>> - rec->u.mem.len);
>> - break;
>> -
>> - case record_full_end: /* end */
>> - rec = record_full_end_alloc ();
>> - record_full_insn_num ++;
>> -
>> - /* Get signal value. */
>> - bfdcore_read (&cbfd, osec, &signal, sizeof (signal),
>> - &bfd_offset);
>> - signal = netorder32 (signal);
>> - rec->u.end.sigval = (enum gdb_signal) signal;
>> -
>> - /* Get insn count. */
>> - bfdcore_read (&cbfd, osec, &count, sizeof (count), &bfd_offset);
>> - count = netorder32 (count);
>> - rec->u.end.insn_num = count;
>> - record_full_insn_count = count + 1;
>> - if (record_debug)
>> - gdb_printf (gdb_stdlog,
>> - " Reading record_full_end (1 + "
>> - "%lu + %lu bytes), offset == %s\n",
>> - (unsigned long) sizeof (signal),
>> - (unsigned long) sizeof (count),
>> - paddress (get_current_arch (),
>> - bfd_offset));
>> - break;
>> -
>> - default:
>> - error (_("Bad entry type in core file %ps."),
>> - styled_string (file_name_style.style (),
>> - bfd_get_filename (&cbfd)));
>> - break;
>> + record_full_read_entry_from_bfd (&cbfd, osec, &bfd_offset);
>> }
>>
>> - /* Add rec to record arch list. */
>> - record_full_arch_list_add (rec);
>> + record_full_save_instruction ();
>> }
>> }
>> catch (const gdb_exception &ex)
>> {
>> - record_full_list_release (record_full_arch_list_tail);
>> + record_full_reset_incomplete ();
>> throw;
>> }
>>
>> - /* Add record_full_arch_list_head to the end of record list. */
>> - record_full_first.next = record_full_arch_list_head;
>> - record_full_arch_list_head->prev = &record_full_first;
>> - record_full_arch_list_tail->next = NULL;
>> - record_full_list = &record_full_first;
>> -
>> /* Update record_full_insn_max_num. */
>> if (record_full_insn_num > record_full_insn_max_num)
>> {
>> @@ -2505,6 +2335,10 @@ record_full_restore (struct bfd &cbfd)
>> record_full_insn_max_num);
>> }
>>
>> + /* When loading a recording, we'll always start at the oldest possible
>> + instruction, no matter where the original recording was stopped. */
>> + record_full_next_insn = 0;
>> +
>> /* Succeeded. */
>> gdb_printf (_("Restored records from core file %s.\n"),
>> bfd_get_filename (&cbfd));
>> @@ -2538,13 +2372,73 @@ cmd_record_full_restore (const char *args, int
>> from_tty)
>> record_full_open (nullptr, from_tty);
>> }
>>
>> +static void
>> +record_full_write_entry_to_bfd (record_full_entry &entry,
>> + gdb_bfd_ref_ptr obfd,
>> + asection *osec, int *bfd_offset,
>> + struct gdbarch *gdbarch)
>> +{
>> + /* Save entry. */
>> + uint8_t type;
>> + uint32_t regnum, len;
>> + uint64_t addr;
>> +
>> + type = entry.type;
>> + bfdcore_write (obfd.get (), osec, &type, sizeof (type), bfd_offset);
>> +
>> + switch (entry.type)
>> + {
>> + case record_full_reg: /* reg */
>> + if (record_debug)
>> + gdb_printf (gdb_stdlog,
>> + " Writing register %d (1 "
>> + "plus %lu plus %d bytes)\n",
>> + entry.u.reg.num,
>> + (unsigned long) sizeof (regnum),
>> + entry.u.reg.len);
>> +
>> + /* Write regnum. */
>> + regnum = netorder32 (entry.u.reg.num);
>> + bfdcore_write (obfd.get (), osec, ®num, sizeof (regnum), bfd_offset);
>> +
>> + /* Write regval. */
>> + bfdcore_write (obfd.get (), osec, record_full_get_loc (&entry),
>> + entry.u.reg.len, bfd_offset);
>> + break;
>> +
>> + case record_full_mem: /* mem */
>> + if (record_debug)
>> + gdb_printf (gdb_stdlog,
>> + " Writing memory %s (1 plus "
>> + "%lu plus %lu plus %d bytes)\n",
>> + paddress (gdbarch,
>> + entry.u.mem.addr),
>> + (unsigned long) sizeof (addr),
>> + (unsigned long) sizeof (len),
>> + entry.u.mem.len);
>> +
>> + /* Write memlen. */
>> + len = netorder32 (entry.u.mem.len);
>> + bfdcore_write (obfd.get (), osec, &len, sizeof (len), bfd_offset);
>> +
>> + /* Write memaddr. */
>> + addr = netorder64 (entry.u.mem.addr);
>> + bfdcore_write (obfd.get (), osec, &addr, sizeof (addr), bfd_offset);
>> +
>> + /* Write memval. */
>> + bfdcore_write (obfd.get (), osec, record_full_get_loc (&entry),
>> + entry.u.mem.len, bfd_offset);
>> + break;
>> + }
>> +
>> +}
>> +
>> /* Save the execution log to a file. We use a modified elf corefile
>> format, with an extra section for our data. */
>>
>> void
>> record_full_base_target::save_record (const char *recfilename)
>> {
>> - struct record_full_entry *cur_record_full_list;
>> uint32_t magic;
>> struct gdbarch *gdbarch;
>> int save_size = 0;
>> @@ -2562,9 +2456,6 @@ record_full_base_target::save_record (const char
>> *recfilename)
>> /* Arrange to remove the output file on failure. */
>> gdb::unlinker unlink_file (recfilename);
>>
>> - /* Save the current record entry to "cur_record_full_list". */
>> - cur_record_full_list = record_full_list;
>> -
>> /* Get the values of regcache and gdbarch. */
>> regcache *regcache = get_thread_regcache (inferior_thread ());
>> gdbarch = regcache->arch ();
>> @@ -2574,34 +2465,27 @@ record_full_base_target::save_record (const
>> char *recfilename)
>> = record_full_gdb_operation_disable_set ();
>>
>> /* Reverse execute to the begin of record list. */
>> - while (1)
>> - {
>> - /* Check for beginning and end of log. */
>> - if (record_full_list == &record_full_first)
>> - break;
>> -
>> - record_full_exec_insn (regcache, gdbarch, record_full_list);
>> -
>> - if (record_full_list->prev)
>> - record_full_list = record_full_list->prev;
>> - }
>> + for (int i = record_full_next_insn - 1; i >= 0; i--)
>> + record_full_exec_insn (regcache, gdbarch,
>> + record_full_list[i]);
>>
>> /* Compute the size needed for the extra bfd section. */
>> save_size = 4; /* magic cookie */
>> - for (record_full_list = record_full_first.next; record_full_list;
>> - record_full_list = record_full_list->next)
>> - switch (record_full_list->type)
>> - {
>> - case record_full_end:
>> - save_size += 1 + 4 + 4;
>> - break;
>> - case record_full_reg:
>> - save_size += 1 + 4 + record_full_list->u.reg.len;
>> - break;
>> - case record_full_mem:
>> - save_size += 1 + 4 + 8 + record_full_list->u.mem.len;
>> - break;
>> - }
>> + for (int i = record_full_list.size () - 1; i >= 0; i--)
>> + {
>> + /* Number of effects of an instruction. */
>> + save_size += sizeof (uint32_t) + sizeof (uint8_t) + sizeof (uint32_t);
>> + for (auto &entry : record_full_list[i].effects)
>> + switch (entry.type)
>> + {
>> + case record_full_reg:
>> + save_size += 1 + 4 + entry.u.reg.len;
>> + break;
>> + case record_full_mem:
>> + save_size += 1 + 4 + 8 + entry.u.mem.len;
>> + break;
>> + }
>> + }
>>
>> /* Make the new bfd section. */
>> osec = bfd_make_section_anyway_with_flags (obfd.get (), "precord",
>> @@ -2630,108 +2514,32 @@ record_full_base_target::save_record (const
>> char *recfilename)
>>
>> /* Save the entries to recfd and forward execute to the end of
>> record list. */
>> - record_full_list = &record_full_first;
>> - while (1)
>> + for (int i = 0; i < record_full_list.size (); i++)
>> {
>> - /* Save entry. */
>> - if (record_full_list != &record_full_first)
>> + uint32_t eff_count = (uint32_t) record_full_list[i].effects.size ();
>> + uint32_t insn_num = record_full_list[i].insn_num;
>> + uint8_t sigval = (record_full_list[i].sigval.has_value ())
>> + ? record_full_list[i].sigval.value ()
>> + : GDB_SIGNAL_0;
>> +
>> + /* Signal. */
>> + bfdcore_write (obfd.get (), osec, &sigval, sizeof (sigval), &bfd_offset);
>> + eff_count = netorder32 (eff_count);
>> + /* Number of effects. */
>> + bfdcore_write (obfd.get (), osec, &eff_count, sizeof (eff_count),
>> + &bfd_offset);
>> + /* Instruction number. */
>> + bfdcore_write (obfd.get (), osec, &insn_num, sizeof (uint32_t),
>> + &bfd_offset);
>> +
>> + for (auto &entry : record_full_list[i].effects)
>> {
>> - uint8_t type;
>> - uint32_t regnum, len, signal, count;
>> - uint64_t addr;
>> -
>> - type = record_full_list->type;
>> - bfdcore_write (obfd.get (), osec, &type, sizeof (type), &bfd_offset);
>> -
>> - switch (record_full_list->type)
>> - {
>> - case record_full_reg: /* reg */
>> - if (record_debug)
>> - gdb_printf (gdb_stdlog,
>> - " Writing register %d (1 "
>> - "plus %lu plus %d bytes)\n",
>> - record_full_list->u.reg.num,
>> - (unsigned long) sizeof (regnum),
>> - record_full_list->u.reg.len);
>> -
>> - /* Write regnum. */
>> - regnum = netorder32 (record_full_list->u.reg.num);
>> - bfdcore_write (obfd.get (), osec, ®num,
>> - sizeof (regnum), &bfd_offset);
>> -
>> - /* Write regval. */
>> - bfdcore_write (obfd.get (), osec,
>> - record_full_get_loc (record_full_list),
>> - record_full_list->u.reg.len, &bfd_offset);
>> - break;
>> -
>> - case record_full_mem: /* mem */
>> - if (record_debug)
>> - gdb_printf (gdb_stdlog,
>> - " Writing memory %s (1 plus "
>> - "%lu plus %lu plus %d bytes)\n",
>> - paddress (gdbarch,
>> - record_full_list->u.mem.addr),
>> - (unsigned long) sizeof (addr),
>> - (unsigned long) sizeof (len),
>> - record_full_list->u.mem.len);
>> -
>> - /* Write memlen. */
>> - len = netorder32 (record_full_list->u.mem.len);
>> - bfdcore_write (obfd.get (), osec, &len, sizeof (len),
>> - &bfd_offset);
>> -
>> - /* Write memaddr. */
>> - addr = netorder64 (record_full_list->u.mem.addr);
>> - bfdcore_write (obfd.get (), osec, &addr,
>> - sizeof (addr), &bfd_offset);
>> -
>> - /* Write memval. */
>> - bfdcore_write (obfd.get (), osec,
>> - record_full_get_loc (record_full_list),
>> - record_full_list->u.mem.len, &bfd_offset);
>> - break;
>> -
>> - case record_full_end:
>> - if (record_debug)
>> - gdb_printf (gdb_stdlog,
>> - " Writing record_full_end (1 + "
>> - "%lu + %lu bytes)\n",
>> - (unsigned long) sizeof (signal),
>> - (unsigned long) sizeof (count));
>> - /* Write signal value. */
>> - signal = netorder32 (record_full_list->u.end.sigval);
>> - bfdcore_write (obfd.get (), osec, &signal,
>> - sizeof (signal), &bfd_offset);
>> -
>> - /* Write insn count. */
>> - count = netorder32 (record_full_list->u.end.insn_num);
>> - bfdcore_write (obfd.get (), osec, &count,
>> - sizeof (count), &bfd_offset);
>> - break;
>> - }
>> + record_full_write_entry_to_bfd (entry, obfd, osec, &bfd_offset,
>> + gdbarch);
>> }
>> -
>> /* Execute entry. */
>> - record_full_exec_insn (regcache, gdbarch, record_full_list);
>> -
>> - if (record_full_list->next)
>> - record_full_list = record_full_list->next;
>> - else
>> - break;
>> - }
>> -
>> - /* Reverse execute to cur_record_full_list. */
>> - while (1)
>> - {
>> - /* Check for beginning and end of log. */
>> - if (record_full_list == cur_record_full_list)
>> - break;
>> -
>> - record_full_exec_insn (regcache, gdbarch, record_full_list);
>> -
>> - if (record_full_list->prev)
>> - record_full_list = record_full_list->prev;
>> + if (i < record_full_next_insn)
>> + record_full_exec_insn (regcache, gdbarch, record_full_list[i]);
>> }
>>
>> unlink_file.keep ();
>> @@ -2746,7 +2554,7 @@ record_full_base_target::save_record (const char
>> *recfilename)
>> correspondingly. */
>>
>> static void
>> -record_full_goto_insn (struct record_full_entry *entry,
>> +record_full_goto_insn (size_t target_insn,
>> enum exec_direction_kind dir)
> You could explain the new parameter in the function description.
>
>> {
>> scoped_restore restore_operation_disable
>> @@ -2757,17 +2565,12 @@ record_full_goto_insn (struct record_full_entry
>> *entry,
>> /* Assume everything is valid: we will hit the entry,
>> and we will not hit the end of the recording. */
>>
>> - if (dir == EXEC_FORWARD)
>> - record_full_list = record_full_list->next;
>> -
>> - do
>> - {
>> - record_full_exec_insn (regcache, gdbarch, record_full_list);
>> - if (dir == EXEC_REVERSE)
>> - record_full_list = record_full_list->prev;
>> - else
>> - record_full_list = record_full_list->next;
>> - } while (record_full_list != entry);
>> + if (dir == EXEC_REVERSE)
>> + for (int i = record_full_next_insn; i > target_insn; i--)
>> + record_full_exec_insn (regcache, gdbarch, record_full_list[i - 1]);
>> + else
>> + for (int i = record_full_next_insn; i < target_insn; i++)
>> + record_full_exec_insn (regcache, gdbarch, record_full_list[i]);
>> }
>>
>> /* Alias for "target record-full". */
>> @@ -2798,61 +2601,36 @@ set_record_full_insn_max_num (const char
>> *args, int from_tty,
>> static void
>> maintenance_print_record_instruction (const char *args, int from_tty)
>> {
>> - struct record_full_entry *to_print = record_full_list;
>> + if (record_full_list.empty ())
>> + error (_("Not enough recorded history"));
>>
>> + int offset = record_full_next_insn - 1;
>> + /* Reduce the offset by 1 if the record_full_next_insn is after the end
>> + so that we show the last recorded instruction instead of crashing. */
>> + if (offset == record_full_list.size ())
>> + offset--;
>> if (args != nullptr)
>> {
>> - int offset = value_as_long (parse_and_eval (args));
>> - if (offset > 0)
>> - {
>> - /* Move forward OFFSET instructions. We know we found the
>> - end of an instruction when to_print->type is record_full_end. */
>> - while (to_print->next != nullptr && offset > 0)
>> - {
>> - to_print = to_print->next;
>> - if (to_print->type == record_full_end)
>> - offset--;
>> - }
>> - if (offset != 0)
>> - error (_("Not enough recorded history"));
>> - }
>> - else
>> - {
>> - while (to_print->prev != nullptr && offset < 0)
>> - {
>> - to_print = to_print->prev;
>> - if (to_print->type == record_full_end)
>> - offset++;
>> - }
>> - if (offset != 0)
>> - error (_("Not enough recorded history"));
>> - }
>> + offset += value_as_long (parse_and_eval (args));
>> + if (offset >= record_full_list.size () || offset < 0)
>> + error (_("Not enough recorded history"));
>> }
>> - gdb_assert (to_print != nullptr);
>> + auto to_print = record_full_list.begin () + offset;
>>
>> gdbarch *arch = current_inferior ()->arch ();
>>
>> - /* Go back to the start of the instruction. */
>> - while (to_print->prev != nullptr && to_print->prev->type != record_full_end)
>> - to_print = to_print->prev;
>> -
>> - /* if we're in the first record, there are no actual instructions
>> - recorded. Warn the user and leave. */
>> - if (to_print == &record_full_first)
>> - error (_("Not enough recorded history"));
>> -
>> - while (to_print->type != record_full_end)
>> + for (auto entry : to_print->effects)
>> {
>> - switch (to_print->type)
>> + switch (entry.type)
>> {
>> case record_full_reg:
>> {
>> - type *regtype = gdbarch_register_type (arch, to_print-
>>> u.reg.num);
>> + type *regtype = gdbarch_register_type (arch, entry.u.reg.num);
>> value *val
>> = value_from_contents (regtype,
>> - record_full_get_loc (to_print));
>> + record_full_get_loc (&entry));
>> gdb_printf ("Register %s changed: ",
>> - gdbarch_register_name (arch, to_print-
>>> u.reg.num));
>> + gdbarch_register_name (arch, entry.u.reg.num));
>> struct value_print_options opts;
>> get_user_print_options (&opts);
>> opts.raw = true;
>> @@ -2862,17 +2640,16 @@ maintenance_print_record_instruction (const
>> char *args, int from_tty)
>> }
>> case record_full_mem:
>> {
>> - gdb_byte *b = record_full_get_loc (to_print);
>> + gdb_byte *b = record_full_get_loc (&entry);
>> gdb_printf ("%d bytes of memory at address %s changed from:",
>> - to_print->u.mem.len,
>> - print_core_address (arch, to_print->u.mem.addr));
>> - for (int i = 0; i < to_print->u.mem.len; i++)
>> + entry.u.mem.len,
>> + print_core_address (arch, entry.u.mem.addr));
>> + for (int i = 0; i < entry.u.mem.len; i++)
>> gdb_printf (" %02x", b[i]);
>> gdb_printf ("\n");
>> break;
>> }
>> }
>> - to_print = to_print->next;
>> }
>> }
>>
>> @@ -2880,11 +2657,6 @@ INIT_GDB_FILE (record_full)
>> {
>> struct cmd_list_element *c;
>>
>> - /* Init record_full_first. */
>> - record_full_first.prev = NULL;
>> - record_full_first.next = NULL;
>> - record_full_first.type = record_full_end;
>> -
>> add_target (record_full_target_info, record_full_open);
>> add_deprecated_target_alias (record_full_target_info, "record");
>> add_target (record_full_core_target_info, record_full_open);
>> diff --git a/gdb/record-full.h b/gdb/record-full.h
>> index 51effe74560..c327d879a8a 100644
>> --- a/gdb/record-full.h
>> +++ b/gdb/record-full.h
>> @@ -41,7 +41,6 @@ enum record_result
>>
>> extern int record_full_arch_list_add_reg (struct regcache *regcache, int
>> num);
>> extern int record_full_arch_list_add_mem (CORE_ADDR addr, int len);
>> -extern int record_full_arch_list_add_end (void);
>>
>> /* Returns true if the process record target is open. */
>> extern int record_full_is_used (void);
>> diff --git a/gdb/riscv-tdep.c b/gdb/riscv-tdep.c
>> index 6b5c9c02d46..f5b1f66844c 100644
>> --- a/gdb/riscv-tdep.c
>> +++ b/gdb/riscv-tdep.c
>> @@ -5466,8 +5466,5 @@ riscv_process_record (struct gdbarch *gdbarch,
>> struct regcache *regcache,
>> if (res != RECORD_SUCCESS)
>> return res;
>>
>> - if (record_full_arch_list_add_end ())
>> - return -1;
>> -
>> return 0;
>> }
>> diff --git a/gdb/rs6000-tdep.c b/gdb/rs6000-tdep.c
>> index e135df94a40..f964889a49f 100644
>> --- a/gdb/rs6000-tdep.c
>> +++ b/gdb/rs6000-tdep.c
>> @@ -7138,8 +7138,6 @@ ppc_process_prefix_instruction (int insn_prefix, int
>> insn_suffix,
>> if (record_full_arch_list_add_reg (regcache, PPC_PC_REGNUM))
>> return -1;
>>
>> - if (record_full_arch_list_add_end ())
>> - return -1;
>> return 0;
>> }
>>
>> @@ -7447,8 +7445,6 @@ ppc_process_record (struct gdbarch *gdbarch,
>> struct regcache *regcache,
>>
>> if (record_full_arch_list_add_reg (regcache, PPC_PC_REGNUM))
>> return -1;
>> - if (record_full_arch_list_add_end ())
>> - return -1;
>> return 0;
>> }
>>
>> diff --git a/gdb/s390-linux-tdep.c b/gdb/s390-linux-tdep.c
>> index 3cd6b359d13..6bea30f08dc 100644
>> --- a/gdb/s390-linux-tdep.c
>> +++ b/gdb/s390-linux-tdep.c
>> @@ -910,9 +910,6 @@ s390_linux_record_signal (struct gdbarch *gdbarch,
>> struct regcache *regcache,
>> if (record_full_arch_list_add_mem (sp, sizeof_rt_sigframe))
>> return -1;
>>
>> - if (record_full_arch_list_add_end ())
>> - return -1;
>> -
>> return 0;
>> }
>>
>> diff --git a/gdb/s390-tdep.c b/gdb/s390-tdep.c
>> index f9d7bdd04e4..36ce659ea15 100644
>> --- a/gdb/s390-tdep.c
>> +++ b/gdb/s390-tdep.c
>> @@ -7019,8 +7019,6 @@ s390_process_record (struct gdbarch *gdbarch,
>> struct regcache *regcache,
>>
>> if (record_full_arch_list_add_reg (regcache, S390_PSWA_REGNUM))
>> return -1;
>> - if (record_full_arch_list_add_end ())
>> - return -1;
>> return 0;
>> }
>>
>> --
>> 2.53.0
>>
> Kind Regards,
> Christina
>
> Intel Deutschland GmbH
> Registered Address: Dornacher Strasse 1, 85622 Feldkirchen, Germany
> Tel: +49 89 991 430, www.intel.de
> Managing Directors: Harry Demas, Jeffrey Schneiderman, Yin Chong Sorrell
> Chairperson of the Supervisory Board: Nicole Lau
> Registered Seat: Munich
> Commercial Register: Amtsgericht Muenchen HRB 186928
>
^ permalink raw reply [flat|nested] 19+ messages in thread
* RE: [PATCH v2 1/6] gdb/record: Refactor record history
2026-05-07 17:38 ` Guinevere Larsen
@ 2026-05-11 15:23 ` Schimpe, Christina
2026-05-12 18:50 ` Guinevere Larsen
0 siblings, 1 reply; 19+ messages in thread
From: Schimpe, Christina @ 2026-05-11 15:23 UTC (permalink / raw)
To: Guinevere Larsen, gdb-patches
Hi Guinevere,
Please find some further comments below.
> -----Original Message-----
> From: Guinevere Larsen <guinevere@redhat.com>
> Sent: Donnerstag, 7. Mai 2026 19:38
> To: Schimpe, Christina <christina.schimpe@intel.com>; gdb-
> patches@sourceware.org
> Subject: Re: [PATCH v2 1/6] gdb/record: Refactor record history
>
> On 5/6/26 6:16 PM, Schimpe, Christina wrote:
> > Hi Guinevere,
> >
> > Thank you for working on this.
> > I found two items that might be worth looking at in more detail, but
> > apart from that it’s mostly minor nits. Please find my feedback below.
> >
> > I don’t have much experience with the record feature, so my review is
> > a bit slow here. To fully understand this patch, I probably need more time,
> > but I wanted to share the comments I already have. Sorry for chiming in
> > so late. I’ll try again tomorrow, or by Friday at the latest.
>
> Hi! Thank you for noting all the inconsistencies, I'll fix almost all of
> them before pushing!
>
> The one thing I don't think it's a good idea is to make the change from
> record_full_list -> record_full_log in this commit... mostly because it
> will introduce untold amounts of rebase conflicts. I'll introduce a
> following commit to this series that will make that renaming, though :)
> --
> Cheers,
> Guinevere Larsen
> It/she
>
> >> -----Original Message-----
> >> From: Guinevere Larsen <guinevere@redhat.com>
> >> Sent: Donnerstag, 23. April 2026 17:26
> >> To: gdb-patches@sourceware.org
> >> Cc: Guinevere Larsen <guinevere@redhat.com>
> >> Subject: [PATCH v2 1/6] gdb/record: Refactor record history
> >>
> >> This is the first step in a large refactor in how GDB keeps execution
> >> history. Rather than using a linked list where multiple entries can
> >> describe a single instruction, the history will now be stored in an
> >> std::deque, each instruction being one entry in the deque.
> >>
> >> The choice was initially to use an std::vector, but it would become
> >> unwieldy because it needs all the memory to be consecutive, which is
> >> hard for 200 thousand entries. Deque was picked because it was a nice
> >> midpoint between vector (maximum cache cohesion) and linked list
> >> (maximum ease of finding space to store more).
> >>
> >> Each instruction in memory will be now one record_full_instruction
> >> entry, which for this commit just contains a vector of
> >> record_full_entry for the effects of the instruction, and the data that
> >> was stored in the record_full_end entry (that is, the instruction number
> >> and the signal, if any).
> >>
> >> This change introduced a minimal performance improvement (what's
> >> important is that it isn't a degradation) and a reduction in the total
> >> memory footprint of roughly 20% if the entire history is used.
> >> ---
> >> gdb/aarch64-tdep.c | 2 -
> >> gdb/amd64-linux-tdep.c | 3 -
> >> gdb/arm-tdep.c | 2 -
> >> gdb/i386-linux-tdep.c | 3 -
> >> gdb/i386-tdep.c | 4 -
> >> gdb/loongarch-tdep.c | 2 -
> >> gdb/moxie-tdep.c | 2 -
> >> gdb/ppc-linux-tdep.c | 3 -
> >> gdb/record-full.c | 1180 ++++++++++++++++------------------------
> >> gdb/record-full.h | 1 -
> >> gdb/riscv-tdep.c | 3 -
> >> gdb/rs6000-tdep.c | 4 -
> >> gdb/s390-linux-tdep.c | 3 -
> >> gdb/s390-tdep.c | 2 -
> >> 14 files changed, 476 insertions(+), 738 deletions(-)
> >>
> >> diff --git a/gdb/aarch64-tdep.c b/gdb/aarch64-tdep.c
> >> index 4befaa2720d..a532992b1d8 100644
> >> --- a/gdb/aarch64-tdep.c
> >> +++ b/gdb/aarch64-tdep.c
> >> @@ -6210,8 +6210,6 @@ aarch64_process_record (struct gdbarch
> *gdbarch,
> >> struct regcache *regcache,
> >> aarch64_record.aarch64_mems[rec_no].len))
> >> ret = -1;
> >>
> >> - if (record_full_arch_list_add_end ())
> >> - ret = -1;
> >> }
> >>
> >> deallocate_reg_mem (&aarch64_record);
> >> diff --git a/gdb/amd64-linux-tdep.c b/gdb/amd64-linux-tdep.c
> >> index a5ac26654cf..9b23db72bbe 100644
> >> --- a/gdb/amd64-linux-tdep.c
> >> +++ b/gdb/amd64-linux-tdep.c
> >> @@ -1591,9 +1591,6 @@ amd64_linux_record_signal (struct gdbarch
> >> *gdbarch,
> >> + AMD64_LINUX_frame_size))
> >> return -1;
> >>
> >> - if (record_full_arch_list_add_end ())
> >> - return -1;
> >> -
> >> return 0;
> >> }
> >>
> >> diff --git a/gdb/arm-tdep.c b/gdb/arm-tdep.c
> >> index 08cce9dbad8..1ce0927f26b 100644
> >> --- a/gdb/arm-tdep.c
> >> +++ b/gdb/arm-tdep.c
> >> @@ -14911,8 +14911,6 @@ arm_process_record (struct gdbarch
> *gdbarch,
> >> struct regcache *regcache,
> >> }
> >> }
> >>
> >> - if (record_full_arch_list_add_end ())
> >> - ret = -1;
> >> }
> >>
> >>
> >> diff --git a/gdb/i386-linux-tdep.c b/gdb/i386-linux-tdep.c
> >> index 23aeccac9fc..4f33766fcdd 100644
> >> --- a/gdb/i386-linux-tdep.c
> >> +++ b/gdb/i386-linux-tdep.c
> >> @@ -949,9 +949,6 @@ i386_linux_record_signal (struct gdbarch
> *gdbarch,
> >> I386_LINUX_xstate +
> >> I386_LINUX_frame_size))
> >> return -1;
> >>
> >> - if (record_full_arch_list_add_end ())
> >> - return -1;
> >> -
> >> return 0;
> >> }
> >>
> >>
> >> diff --git a/gdb/i386-tdep.c b/gdb/i386-tdep.c
> >> index fa935b5fcdb..fee36b46a73 100644
> >> --- a/gdb/i386-tdep.c
> >> +++ b/gdb/i386-tdep.c
> >> @@ -5201,8 +5201,6 @@ i386_record_vex (struct i386_record_s *ir,
> uint8_t
> >> vex_w, uint8_t vex_r,
> >> }
> >>
> >> record_full_arch_list_add_reg (ir->regcache, ir-
> >>> regmap[X86_RECORD_REIP_REGNUM]);
> >> - if (record_full_arch_list_add_end ())
> >> - return -1;
> >>
> >> return 0;
> >> }
> >> @@ -8359,8 +8357,6 @@ Do you want to stop the program?"),
> >>
> >> /* In the future, maybe still need to deal with need_dasm. */
> >> I386_RECORD_FULL_ARCH_LIST_ADD_REG
> (X86_RECORD_REIP_REGNUM);
> >> - if (record_full_arch_list_add_end ())
> >> - return -1;
> >>
> >> return 0;
> >>
> >> diff --git a/gdb/loongarch-tdep.c b/gdb/loongarch-tdep.c
> >> index 225b1abb703..5ec6b2a48d0 100644
> >> --- a/gdb/loongarch-tdep.c
> >> +++ b/gdb/loongarch-tdep.c
> >> @@ -2789,8 +2789,6 @@ loongarch_process_record (struct gdbarch
> >> *gdbarch, struct regcache *regcache,
> >> LOONGARCH_PC_REGNUM))
> >> return -1;
> >>
> >> - if (record_full_arch_list_add_end ())
> >> - return -1;
> >> }
> >>
> >> return ret;
> >> diff --git a/gdb/moxie-tdep.c b/gdb/moxie-tdep.c
> >> index c8a04d21f59..2f8f0186488 100644
> >> --- a/gdb/moxie-tdep.c
> >> +++ b/gdb/moxie-tdep.c
> >> @@ -1040,8 +1040,6 @@ moxie_process_record (struct gdbarch
> *gdbarch,
> >> struct regcache *regcache,
> >>
> >> if (record_full_arch_list_add_reg (regcache, MOXIE_PC_REGNUM))
> >> return -1;
> >> - if (record_full_arch_list_add_end ())
> >> - return -1;
> >> return 0;
> >> }
> >>
> >> diff --git a/gdb/ppc-linux-tdep.c b/gdb/ppc-linux-tdep.c
> >> index 19698eaacbe..e2f53551709 100644
> >> --- a/gdb/ppc-linux-tdep.c
> >> +++ b/gdb/ppc-linux-tdep.c
> >> @@ -1565,9 +1565,6 @@ ppc_linux_record_signal (struct gdbarch
> *gdbarch,
> >> struct regcache *regcache,
> >> if (record_full_arch_list_add_mem (sp, SIGNAL_FRAMESIZE +
> >> sizeof_rt_sigframe))
> >> return -1;
> >>
> >> - if (record_full_arch_list_add_end ())
> >> - return -1;
> >> -
> >> return 0;
> >> }
> >>
> >> diff --git a/gdb/record-full.c b/gdb/record-full.c
> >> index 69d2c100e57..aac69cee17e 100644
> >> --- a/gdb/record-full.c
> >> +++ b/gdb/record-full.c
> > I think we should include vector, optional and deque directly.
> >
> >> @@ -72,20 +72,17 @@
> >> #define DEFAULT_RECORD_FULL_INSN_MAX_NUM 200000
> >>
> >> #define RECORD_FULL_IS_REPLAY \
> >> - (record_full_list->next || ::execution_direction == EXEC_REVERSE)
> >> + ( (record_full_next_insn != record_full_list.size ()) \
> > Nit: No whitespace after the first bracket:
> > => ((record_full_next_insn != record_full_list.size ()) \
> >
> >> + || ::execution_direction == EXEC_REVERSE)
> >>
> >> #define RECORD_FULL_FILE_MAGIC netorder32(0x20091016)
> >>
> >> /* These are the core structs of the process record functionality.
> >>
> >> A record_full_entry is a record of the value change of a register
> >> - ("record_full_reg") or a part of memory ("record_full_mem"). And each
> >> - instruction must have a struct record_full_entry ("record_full_end")
> >> - that indicates that this is the last struct record_full_entry of this
> >> - instruction.
> >> -
> >> - Each struct record_full_entry is linked to "record_full_list" by "prev"
> >> - and "next" pointers. */
> >> + ("record_full_reg") or a part of memory ("record_full_mem").
> >> + These are saved on the record_full_instruction struct, which also
> >> + contains some extra information, such as delivered signals. */
> >>
> >> struct record_full_mem_entry
> >> {
> >> @@ -112,47 +109,14 @@ struct record_full_reg_entry
> >> } u;
> >> };
> >>
> >> -struct record_full_end_entry
> >> -{
> >> - enum gdb_signal sigval;
> >> - ULONGEST insn_num;
> >> -};
> >> -
> >> enum record_full_type
> >> {
> >> - record_full_end = 0,
> >> record_full_reg,
> >> record_full_mem
> >> };
> >>
> >> -/* This is the data structure that makes up the execution log.
> >> -
> >> - The execution log consists of a single linked list of entries
> >> - of type "struct record_full_entry". It is doubly linked so that it
> >> - can be traversed in either direction.
> >> -
> >> - The start of the list is anchored by a struct called
> >> - "record_full_first". The pointer "record_full_list" either points
> >> - to the last entry that was added to the list (in record mode), or to
> >> - the next entry in the list that will be executed (in replay mode).
> >> -
> >> - Each list element (struct record_full_entry), in addition to next
> >> - and prev pointers, consists of a union of three entry types: mem,
> >> - reg, and end. A field called "type" determines which entry type is
> >> - represented by a given list element.
> >> -
> >> - Each instruction that is added to the execution log is represented
> >> - by a variable number of list elements ('entries'). The instruction
> >> - will have one "reg" entry for each register that is changed by
> >> - executing the instruction (including the PC in every case). It
> >> - will also have one "mem" entry for each memory change. Finally,
> >> - each instruction will have an "end" entry that separates it from
> >> - the changes associated with the next instruction. */
> >> -
> >> struct record_full_entry
> >> {
> >> - struct record_full_entry *prev;
> >> - struct record_full_entry *next;
> >> enum record_full_type type;
> >> union
> >> {
> >> @@ -160,11 +124,31 @@ struct record_full_entry
> >> struct record_full_reg_entry reg;
> >> /* mem */
> >> struct record_full_mem_entry mem;
> >> - /* end */
> >> - struct record_full_end_entry end;
> >> } u;
> >> };
> >>
> >> +/* This is the main structure that comprises the execution log.
> >> + Each instruction is comprised of:
> >> + * The instruction number: How many instructions were recorded before
> >> + this one;
> >> + * sigval: Whether the inferior received a signal while the following
> >> + instruction was being recorded;
It might be worth describing in the comment in which cases this does not
have a value, to point out the reason why this is now optional.
As I understand it before this patch we used GDB_SIGNAL_0 for this case, is that right?
> >> + * effects: A list of record_full_entry structures, each of which
> >> + describing one effect that the instruction has on the inferior.
> >> +
> >> + Note, the signal is stored in the previous instruction for historical
> >> + reasons. This is how it was first implemented, and no one has gotten
> >> + around to changing it yet. */
> >> +
> >> +struct record_full_instruction
> >> +{
> >> + /* This might be different from the index if
> >> + we had to remove the first few instructions. */
> >> + uint32_t insn_num;
> >> + std::optional<gdb_signal> sigval;
> >> + std::vector<record_full_entry> effects;
> >> +};
> >> +
> >> /* If true, query if PREC cannot record memory
> >> change of next instruction. */
> >> bool record_full_memory_query = false;
> >> @@ -181,27 +165,25 @@ static detached_regcache
> >> *record_full_core_regbuf = NULL;
> >> static std::vector<target_section> record_full_core_sections;
> >> static struct record_full_core_buf_entry *record_full_core_buf_list =
> NULL;
> >>
> >> -/* The following variables are used for managing the linked list that
> >> - represents the execution log.
> >> +/* The following variables are used for managing the history of executed
> >> + instructions from the inferior.
> >>
> >> - record_full_first is the anchor that holds down the beginning of
> >> - the list.
> >> + record_full_list contains all instructions that were fully executed and
> >> + saved to the log, so that we can replay the execution.
> >>
> >> - record_full_list serves two functions:
> >> - 1) In record mode, it anchors the end of the list.
> >> - 2) In replay mode, it traverses the list and points to
> >> - the next instruction that must be emulated.
> >> + record_full_next_insn always points to the next instruction that would
> >> + be executed if the inferior executes forward. In the special case when
> >> + the inferior is not replaying, record_full_next_insn points past the
> >> + end of the history.
> >>
> >> - record_full_arch_list_head and record_full_arch_list_tail are used
> >> - to manage a separate list, which is used to build up the change
> >> - elements of the currently executing instruction during record mode.
> >> - When this instruction has been completely annotated in the "arch
> >> - list", it will be appended to the main execution log. */
> >> + record_full_incomplete_instruction holds a partial instruction, while
> >> + the lower target is disassembling the instruction, or as partial xfers are
> >> + happening. It is manipulated by the "arch list" functions for historical
> >> + reasons. */
> >>
> >> -static struct record_full_entry record_full_first;
> >> -static struct record_full_entry *record_full_list = &record_full_first;
> >> -static struct record_full_entry *record_full_arch_list_head = NULL;
> >> -static struct record_full_entry *record_full_arch_list_tail = NULL;
> >> +static std::deque<record_full_instruction> record_full_list;
> > Given that this is not a list anymore I wonder if we should better call this
> sth. like
> > record_full_history or record_full_log or even simply
> recorded_instructions?
> >
> >> +static record_full_instruction record_full_incomplete_instruction;
> >> +int record_full_next_insn;
Any particular reason why this is not static?
> >>
> >> /* true ask user. false auto delete the last struct record_full_entry. */
> >> static bool record_full_stop_at_limit = true;
> >> @@ -361,6 +343,14 @@ record_full_target::kill ()
> >> record_kill (this);
> >> }
> >>
> >> +static void
> >> +record_full_reset_incomplete ()
> >> +{
> >> + record_full_incomplete_instruction.effects.clear ();
> >> + record_full_incomplete_instruction.sigval.reset ();
> >> + record_full_incomplete_instruction.insn_num = 0;
> >> +}
> >> +
> >> /* See record-full.h. */
> >>
> >> int
> >> @@ -390,156 +380,120 @@ static struct cmd_list_element
> >> *show_record_full_cmdlist;
> >> /* Command list for "record full". */
> >> static struct cmd_list_element *record_full_cmdlist;
> >>
> >> -static void record_full_goto_insn (struct record_full_entry *entry,
> >> +static void record_full_goto_insn (size_t target_insn,
> >> enum exec_direction_kind dir);
> >>
> >> -/* Alloc and free functions for record_full_reg, record_full_mem, and
> >> - record_full_end entries. */
> >> +/* Initialization and cleanup functions for record_full_reg and
> >> + record_full_mem entries. */
> >>
> >> -/* Alloc a record_full_reg record entry. */
> >> +/* Init a record_full_reg record entry. */
> >>
> >> -static inline struct record_full_entry *
> >> -record_full_reg_alloc (struct regcache *regcache, int regnum)
> >> +static inline struct record_full_entry
> >> +record_full_reg_init (struct regcache *regcache, int regnum)
> >> {
> >> - struct record_full_entry *rec;
> >> + struct record_full_entry rec;
> >> struct gdbarch *gdbarch = regcache->arch ();
> >>
> >> - rec = XCNEW (struct record_full_entry);
> >> - rec->type = record_full_reg;
> >> - rec->u.reg.num = regnum;
> >> - rec->u.reg.len = register_size (gdbarch, regnum);
> >> - if (rec->u.reg.len > sizeof (rec->u.reg.u.buf))
> >> - rec->u.reg.u.ptr = (gdb_byte *) xmalloc (rec->u.reg.len);
> >> + rec.type = record_full_reg;
> >> + rec.u.reg.num = regnum;
> >> + rec.u.reg.len = register_size (gdbarch, regnum);
> >> + if (rec.u.reg.len > sizeof (rec.u.reg.u.buf))
> >> + rec.u.reg.u.ptr = (gdb_byte *) xmalloc (rec.u.reg.len);
> >>
> >> return rec;
> >> }
> >>
> >> -/* Free a record_full_reg record entry. */
> >> +/* Cleanup a record_full_reg record entry. */
> >>
> >> static inline void
> >> -record_full_reg_release (struct record_full_entry *rec)
> >> +record_full_reg_cleanup (struct record_full_entry rec)
> >> {
> >> - gdb_assert (rec->type == record_full_reg);
> >> - if (rec->u.reg.len > sizeof (rec->u.reg.u.buf))
> >> - xfree (rec->u.reg.u.ptr);
> >> - xfree (rec);
> >> + gdb_assert (rec.type == record_full_reg);
> >> + if (rec.u.reg.len > sizeof (rec.u.reg.u.buf))
> >> + xfree (rec.u.reg.u.ptr);
> >> }
> >>
> >> -/* Alloc a record_full_mem record entry. */
> >> +/* Init a record_full_mem record entry. */
> >>
> >> -static inline struct record_full_entry *
> >> -record_full_mem_alloc (CORE_ADDR addr, int len)
> >> +static inline struct record_full_entry
> >> +record_full_mem_init (CORE_ADDR addr, int len)
> >> {
> >> - struct record_full_entry *rec;
> >> + struct record_full_entry rec;
> >>
> >> - rec = XCNEW (struct record_full_entry);
> >> - rec->type = record_full_mem;
> >> - rec->u.mem.addr = addr;
> >> - rec->u.mem.len = len;
> >> - if (rec->u.mem.len > sizeof (rec->u.mem.u.buf))
> >> - rec->u.mem.u.ptr = (gdb_byte *) xmalloc (len);
> >> + rec.type = record_full_mem;
> >> + rec.u.mem.addr = addr;
> >> + rec.u.mem.len = len;
> >> + if (rec.u.mem.len > sizeof (rec.u.mem.u.buf))
> >> + rec.u.mem.u.ptr = (gdb_byte *) xmalloc (len);
> >> + rec.u.mem.mem_entry_not_accessible = 0;
> >>
> >> return rec;
> >> }
> >>
> >> -/* Free a record_full_mem record entry. */
> >> +/* Cleanup a record_full_mem record entry. */
> >>
> >> static inline void
> >> -record_full_mem_release (struct record_full_entry *rec)
> >> -{
> >> - gdb_assert (rec->type == record_full_mem);
> >> - if (rec->u.mem.len > sizeof (rec->u.mem.u.buf))
> >> - xfree (rec->u.mem.u.ptr);
> >> - xfree (rec);
> >> -}
> >> -
> >> -/* Alloc a record_full_end record entry. */
> >> -
> >> -static inline struct record_full_entry *
> >> -record_full_end_alloc (void)
> >> +record_full_mem_cleanup (struct record_full_entry rec)
> >> {
> >> - struct record_full_entry *rec;
> >> -
> >> - rec = XCNEW (struct record_full_entry);
> >> - rec->type = record_full_end;
> >> -
> >> - return rec;
> >> + gdb_assert (rec.type == record_full_mem);
> >> + if (rec.u.mem.len > sizeof (rec.u.mem.u.buf))
> >> + xfree (rec.u.mem.u.ptr);
> >> }
> >>
> >> -/* Free a record_full_end record entry. */
> >> +/* Free one record entry, any type. */
> >>
> >> static inline void
> >> -record_full_end_release (struct record_full_entry *rec)
> >> -{
> >> - xfree (rec);
> >> -}
> >> -
> >> -/* Free one record entry, any type.
> >> - Return entry->type, in case caller wants to know. */
> >> -
> >> -static inline enum record_full_type
> >> -record_full_entry_release (struct record_full_entry *rec)
> >> +record_full_entry_cleanup (struct record_full_entry rec)
> >> {
> >> - enum record_full_type type = rec->type;
> >>
> >> - switch (type) {
> >> + switch (rec.type) {
> >> case record_full_reg:
> >> - record_full_reg_release (rec);
> >> + record_full_reg_cleanup (rec);
> >> break;
> >> case record_full_mem:
> >> - record_full_mem_release (rec);
> >> - break;
> >> - case record_full_end:
> >> - record_full_end_release (rec);
> >> + record_full_mem_cleanup (rec);
> >> break;
> >> }
> >> - return type;
> >> }
> >>
> >> -/* Free all record entries in list pointed to by REC. */
> >> -
> >> static void
> >> -record_full_list_release (struct record_full_entry *rec)
> >> +record_full_reset_history ()
> >> {
> >> - if (!rec)
> >> - return;
> >> -
> >> - while (rec->next)
> >> - rec = rec->next;
> >> + record_full_insn_num = 0;
> >> + record_full_insn_count = 0;
> >> + record_full_next_insn = 0;
> >>
> >> - while (rec->prev)
> >> + for (auto &insn : record_full_list)
> >> {
> >> - rec = rec->prev;
> >> - record_full_entry_release (rec->next);
> >> + for (auto &entry : insn.effects)
> >> + record_full_entry_cleanup (entry);
> >> }
> >>
> >> - if (rec == &record_full_first)
> >> - {
> >> - record_full_insn_num = 0;
> >> - record_full_first.next = NULL;
> >> - }
> >> - else
> >> - record_full_entry_release (rec);
> >> + record_full_list.clear ();
> >> }
> >>
> >> -/* Free all record entries forward of the given list position. */
> >> -
> >> static void
> >> -record_full_list_release_following (struct record_full_entry *rec)
> >> +record_full_list_release_following (int index)
> >> {
> >> - struct record_full_entry *tmp = rec->next;
> >> -
> >> - rec->next = NULL;
> >> - while (tmp)
> >> + for (int i = record_full_list.size () - 1; i > index; i--)
> >> {
> >> - rec = tmp->next;
> >> - if (record_full_entry_release (tmp) == record_full_end)
> >> - {
> >> - record_full_insn_num--;
> >> - record_full_insn_count--;
> >> - }
> >> - tmp = rec;
> >> + for (auto &entry : record_full_list[i].effects)
> >> + record_full_entry_cleanup (entry);
> >> + record_full_list.pop_back ();
> >> }
> >> + /* Set the next instruction to be past the end of the log so we
> >> + start recording if the user moves forward again. */
> >> + record_full_next_insn = index;
> >> +}
>
> >> +static void
> >> +record_full_save_instruction ()
A function comment would be nice.
> >> +{
> >> + ++record_full_insn_count;
> >> + record_full_incomplete_instruction.insn_num = record_full_insn_count;
> >> + record_full_incomplete_instruction.effects.shrink_to_fit ();
> >> + record_full_list.push_back (record_full_incomplete_instruction);
I think this line will at some point call the default copy constructor of record_full_mem_entry
and record_full_reg_entry, which have those buffers:
gdb_byte buf[sizeof (gdb_byte *)];
IIUC you'll only have a shallow copy. Should we use a std::move instead here?
I further wonder if this problem might be related to the double free issues you
describe in patch #3. Would you mind checking?
And if you add the destructor, I think it would make sense to add a copy constructor etc., too:
https://en.cppreference.com/cpp/language/rule_of_three
> >> + record_full_next_insn++;
> >> }
> >>
> >> /* Delete the first instruction from the beginning of the log, to make
> >> @@ -550,52 +504,22 @@ record_full_list_release_following (struct
> >> record_full_entry *rec)
> >> static void
> >> record_full_list_release_first (void)
> >> {
> >> - struct record_full_entry *tmp;
> >> -
> >> - if (!record_full_first.next)
> >> + if (record_full_list.empty ())
> >> return;
> >>
> >> - /* Loop until a record_full_end. */
> >> - while (1)
> >> - {
> >> - /* Cut record_full_first.next out of the linked list. */
> >> - tmp = record_full_first.next;
> >> - record_full_first.next = tmp->next;
> >> - tmp->next->prev = &record_full_first;
> >> -
> >> - /* tmp is now isolated, and can be deleted. */
> >> - if (record_full_entry_release (tmp) == record_full_end)
> >> - break; /* End loop at first record_full_end. */
> >> + for (auto &entry : record_full_list[0].effects)
> >> + record_full_entry_cleanup (entry);
> >>
> >> - if (!record_full_first.next)
> >> - {
> >> - gdb_assert (record_full_insn_num == 1);
> >> - break; /* End loop when list is empty. */
> >> - }
> >> - }
> >> + record_full_list.pop_front ();
> >> + --record_full_next_insn;
> >> }
> >>
> >> /* Add a struct record_full_entry to record_full_arch_list. */
> >>
> >> static void
> >> -record_full_arch_list_add (struct record_full_entry *rec)
> >> +record_full_arch_list_add (struct record_full_entry &rec)
> >> {
> >> - if (record_debug > 1)
> >> - gdb_printf (gdb_stdlog,
> >> - "Process record: record_full_arch_list_add %s.\n",
> >> - host_address_to_string (rec));
> >> -
> >> - if (record_full_arch_list_tail)
> >> - {
> >> - record_full_arch_list_tail->next = rec;
> >> - rec->prev = record_full_arch_list_tail;
> >> - record_full_arch_list_tail = rec;
> >> - }
> >> - else
> >> - {
> >> - record_full_arch_list_head = rec;
> >> - record_full_arch_list_tail = rec;
> >> - }
> >> + record_full_incomplete_instruction.effects.push_back (rec);
> >> }
> >>
> >> /* Return the value storage location of a record entry. */
> >> @@ -613,7 +537,6 @@ record_full_get_loc (struct record_full_entry *rec)
> >> return rec->u.reg.u.ptr;
> >> else
> >> return rec->u.reg.u.buf;
> >> - case record_full_end:
> >> default:
> >> gdb_assert_not_reached ("unexpected record_full_entry type");
> >> return NULL;
> >> @@ -625,7 +548,7 @@ record_full_get_loc (struct record_full_entry *rec)
> >> int
> >> record_full_arch_list_add_reg (struct regcache *regcache, int regnum)
> >> {
> >> - struct record_full_entry *rec;
> >> + struct record_full_entry rec;
> > I think we can omit the struct keyword here (there are some more
> occurrences in this patch).
> >
> >> if (record_debug > 1)
> >> gdb_printf (gdb_stdlog,
> >> @@ -633,9 +556,9 @@ record_full_arch_list_add_reg (struct regcache
> >> *regcache, int regnum)
> >> "record list.\n",
> >> regnum);
> >>
> >> - rec = record_full_reg_alloc (regcache, regnum);
> >> + rec = record_full_reg_init (regcache, regnum);
> >>
> >> - regcache->cooked_read (regnum, record_full_get_loc (rec));
> >> + regcache->cooked_read (regnum, record_full_get_loc (&rec));
> >>
> >> record_full_arch_list_add (rec);
> >>
> >> @@ -648,7 +571,7 @@ record_full_arch_list_add_reg (struct regcache
> >> *regcache, int regnum)
> >> int
> >> record_full_arch_list_add_mem (CORE_ADDR addr, int len)
> >> {
> >> - struct record_full_entry *rec;
> >> + struct record_full_entry rec;
> >>
> >> if (record_debug > 1)
> >> gdb_printf (gdb_stdlog,
> >> @@ -659,12 +582,12 @@ record_full_arch_list_add_mem (CORE_ADDR
> addr,
> >> int len)
> >> if (!addr) /* FIXME: Why? Some arch must permit it... */
> >> return 0;
> >>
> >> - rec = record_full_mem_alloc (addr, len);
> >> + rec = record_full_mem_init (addr, len);
> >>
> >> if (record_read_memory (current_inferior ()->arch (), addr,
> >> - record_full_get_loc (rec), len))
> >> + record_full_get_loc (&rec), len))
> >> {
> >> - record_full_mem_release (rec);
> >> + record_full_mem_cleanup (rec);
> >> return -1;
> >> }
> >>
> >> @@ -673,27 +596,6 @@ record_full_arch_list_add_mem (CORE_ADDR
> addr,
> >> int len)
> >> return 0;
> >> }
> >>
> >> -/* Add a record_full_end type struct record_full_entry to
> >> - record_full_arch_list. */
> >> -
> >> -int
> >> -record_full_arch_list_add_end (void)
> >> -{
> >> - struct record_full_entry *rec;
> >> -
> >> - if (record_debug > 1)
> >> - gdb_printf (gdb_stdlog,
> >> - "Process record: add end to arch list.\n");
> >> -
> >> - rec = record_full_end_alloc ();
> >> - rec->u.end.sigval = GDB_SIGNAL_0;
> >> - rec->u.end.insn_num = ++record_full_insn_count;
> >> -
> >> - record_full_arch_list_add (rec);
> >> -
> >> - return 0;
> >> -}
> >> -
> >> static void
> >> record_full_check_insn_num (void)
> >> {
> >> @@ -725,8 +627,7 @@ record_full_message (struct regcache *regcache,
> >> enum gdb_signal signal)
> >>
> >> try
> >> {
> >> - record_full_arch_list_head = NULL;
> >> - record_full_arch_list_tail = NULL;
> >> + record_full_reset_incomplete ();
> >>
> >> /* Check record_full_insn_num. */
> >> record_full_check_insn_num ();
> >> @@ -746,20 +647,16 @@ record_full_message (struct regcache
> *regcache,
> >> enum gdb_signal signal)
> >> the user says something different, like "deliver this signal"
> >> during the replay mode).
> >>
> >> - User should understand that nothing he does during the replay
> >> - mode will change the behavior of the child. If he tries,
> >> + User should understand that nothing they do during the replay
> >> + mode will change the behavior of the child. If they try,
> >> then that is a user error.
> >>
> >> But we should still deliver the signal to gdb during the replay,
> >> if we delivered it during the recording. Therefore we should
> >> record the signal during record_full_wait, not
> >> record_full_resume. */
> >> - if (record_full_list != &record_full_first) /* FIXME better way
> >> - to check */
> >> - {
> >> - gdb_assert (record_full_list->type == record_full_end);
> >> - record_full_list->u.end.sigval = signal;
> >> - }
> >> + if (signal != GDB_SIGNAL_0)
> >> + record_full_list[record_full_next_insn - 1].sigval = signal;
Similar comment as already in my earlier review:
Can record_full_next_insn be == 0 here or may record_full_list be empty ?
I think it might be worth checking the patch if there are more similar issues.
The old patch had more guards to check this.
And I noticed in some other locations you cast it:
if (sigval != GDB_SIGNAL_0)
record_full_incomplete_instruction.sigval = (gdb_signal) sigval;
Not sure if this is necessary or not, but it might be for checking and making it consistent?
And is it intended that now we don't clear sigval anymore?
Shouldn't we set it to std::nullopt in case signal == GDB_SIGNAL_0, to match the original
behaviour?
> >> if (signal == GDB_SIGNAL_0
> >> || !gdbarch_process_record_signal_p (gdbarch))
> >> @@ -778,13 +675,11 @@ record_full_message (struct regcache
> *regcache,
> >> enum gdb_signal signal)
> >> }
> >> catch (const gdb_exception &ex)
> >> {
> >> - record_full_list_release (record_full_arch_list_tail);
> >> + record_full_reset_incomplete ();
> >> throw;
> >> }
> >>
> >> - record_full_list->next = record_full_arch_list_head;
> >> - record_full_arch_list_head->prev = record_full_list;
> >> - record_full_list = record_full_arch_list_tail;
> >> + record_full_save_instruction ();
> >>
> >> if (record_full_insn_num == record_full_insn_max_num)
> >> record_full_list_release_first ();
> >> @@ -829,9 +724,9 @@ static enum target_stop_reason
> >> record_full_stop_reason
> >> entries and memory entries, followed by an 'end' entry. */
> >>
> >> static inline void
> >> -record_full_exec_insn (struct regcache *regcache,
> >> - struct gdbarch *gdbarch,
> >> - struct record_full_entry *entry)
> >> +record_full_exec_entry (struct regcache *regcache,
> >> + struct gdbarch *gdbarch,
> >> + struct record_full_entry *entry)
> > Nit: omit struct keywords
> > And there are some more places in this series/patch, but I will stop
> commenting
> > now on all of them.
> >
> >> {
> >> switch (entry->type)
> >> {
> >> @@ -909,6 +804,15 @@ record_full_exec_insn (struct regcache
> *regcache,
> >> }
> >> }
> >>
> >> +static inline void
> >> +record_full_exec_insn (struct regcache *regcache,
> >> + struct gdbarch *gdbarch,
> >> + record_full_instruction &insn)
> >> +{
> >> + for (auto &entry : insn.effects)
> >> + record_full_exec_entry (regcache, gdbarch, &entry);
> >> +}
> >> +
> >> static void record_full_restore (struct bfd &cbfd);
> >>
> >> /* Asynchronous signal handle registered as event loop source for when
> >> @@ -983,10 +887,7 @@ record_full_open (const char *args, int from_tty)
> >> record_preopen ();
> >>
> >> /* Reset */
> >> - record_full_insn_num = 0;
> >> - record_full_insn_count = 0;
> >> - record_full_list = &record_full_first;
> >> - record_full_list->next = NULL;
> >> + record_full_reset_history ();
> >>
> >> bfd *cbfd = get_inferior_core_bfd (current_inferior ());
> >> if (cbfd != nullptr)
> >> @@ -1014,7 +915,7 @@ record_full_base_target::close ()
> >> if (record_debug)
> >> gdb_printf (gdb_stdlog, "Process record: record_full_close\n");
> >>
> >> - record_full_list_release (record_full_list);
> >> + record_full_reset_history ();
> >>
> >> /* Release record_full_core_regbuf. */
> >> if (record_full_core_regbuf)
> >> @@ -1313,7 +1214,6 @@ record_full_wait_1 (struct target_ops *ops,
> >> struct gdbarch *gdbarch = regcache->arch ();
> >> const address_space *aspace = current_inferior ()->aspace.get ();
> >> int continue_flag = 1;
> >> - int first_record_full_end = 1;
> >>
> >> try
> >> {
> >> @@ -1322,7 +1222,6 @@ record_full_wait_1 (struct target_ops *ops,
> >> record_full_stop_reason = TARGET_STOPPED_BY_NO_REASON;
> >> status->set_stopped (GDB_SIGNAL_0);
> >>
> >> - /* Check breakpoint when forward execute. */
> >> if (execution_direction == EXEC_FORWARD)
> >> {
> >> tmp_pc = regcache_read_pc (regcache);
> >> @@ -1330,8 +1229,7 @@ record_full_wait_1 (struct target_ops *ops,
> >>
> >> &record_full_stop_reason))
> >> {
> >> if (record_debug)
> >> - gdb_printf (gdb_stdlog,
> >> - "Process record: break at %s.\n",
> >> + gdb_printf (gdb_stdlog, "Process record: break at %s.\n",
> >> paddress (gdbarch, tmp_pc));
> >> goto replay_out;
> >> }
> >> @@ -1344,10 +1242,10 @@ record_full_wait_1 (struct target_ops *ops,
> >> the signal. */
> >> target_terminal::ours ();
> >>
> >> - /* In EXEC_FORWARD mode, record_full_list points to the tail of
> prev
> >> - instruction. */
> >> - if (execution_direction == EXEC_FORWARD && record_full_list-
> >next)
> >> - record_full_list = record_full_list->next;
> >> + /* In EXEC_FORWARD mode, record_full_next_insn is the next
> >> + instruction to be executed. */
> >> + if (execution_direction == EXEC_REVERSE)
> >> + record_full_next_insn--;
> >>
> >> /* Loop over the record_full_list, looking for the next place to
> >> stop. */
> >> @@ -1355,108 +1253,92 @@ record_full_wait_1 (struct target_ops *ops,
> >> {
> >> /* Check for beginning and end of log. */
> >> if (execution_direction == EXEC_REVERSE
> >> - && record_full_list == &record_full_first)
> >> + && record_full_next_insn < 0)
> >> {
> >> /* Hit beginning of record log in reverse. */
> >> status->set_no_history ();
> >> + record_full_next_insn = 0;
> >> break;
> >> }
> >> if (execution_direction != EXEC_REVERSE
> >> - && !record_full_list->next)
> >> + && record_full_next_insn == record_full_list.size ())
> >> {
> >> /* Hit end of record log going forward. */
> >> status->set_no_history ();
> >> break;
> >> }
> >>
> >> - record_full_exec_insn (regcache, gdbarch, record_full_list);
> >> + record_full_exec_insn
> >> + (regcache, gdbarch,
> >> + record_full_list[record_full_next_insn]);
> >>
> >> - if (record_full_list->type == record_full_end)
> >> + /* step */
> >> + if (record_full_resume_step)
> >> {
> >> if (record_debug > 1)
> >> - gdb_printf
> >> - (gdb_stdlog,
> >> - "Process record: record_full_end %s to "
> >> - "inferior.\n",
> >> - host_address_to_string (record_full_list));
> >> -
> >> - if (first_record_full_end
> >> - && execution_direction == EXEC_REVERSE)
> >> - {
> >> - /* When reverse execute, the first
> >> - record_full_end is the part of current
> >> - instruction. */
> >> - first_record_full_end = 0;
> >> - }
> >> - else
> >> - {
> >> - /* In EXEC_REVERSE mode, this is the
> >> - record_full_end of prev instruction. In
> >> - EXEC_FORWARD mode, this is the
> >> - record_full_end of current instruction. */
> >> - /* step */
> >> - if (record_full_resume_step)
> >> - {
> >> - if (record_debug > 1)
> >> - gdb_printf (gdb_stdlog,
> >> - "Process record: step.\n");
> >> - continue_flag = 0;
> >> - }
> >> -
> >> - /* check breakpoint */
> >> - tmp_pc = regcache_read_pc (regcache);
> >> - if (record_check_stopped_by_breakpoint
> >> - (aspace, tmp_pc, &record_full_stop_reason))
> >> - {
> >> - if (record_debug)
> >> - gdb_printf (gdb_stdlog,
> >> - "Process record: break "
> >> - "at %s.\n",
> >> - paddress (gdbarch, tmp_pc));
> >> + gdb_printf (gdb_stdlog,
> >> + "Process record: step.\n");
> >> + continue_flag = 0;
> >> + }
> >>
> >> - continue_flag = 0;
> >> - }
> >> + /* check breakpoint */
> >> + tmp_pc = regcache_read_pc (regcache);
> >> + if (record_check_stopped_by_breakpoint
> >> + (aspace, tmp_pc, &record_full_stop_reason))
> >> + {
> >> + if (record_debug)
> >> + gdb_printf (gdb_stdlog,
> >> + "Process record: break "
> >> + "at %s.\n",
> >> + paddress (gdbarch, tmp_pc));
> >>
> >> - if (record_full_stop_reason
> >> - == TARGET_STOPPED_BY_WATCHPOINT)
> >> - {
> >> - if (record_debug)
> >> - gdb_printf (gdb_stdlog,
> >> - "Process record: hit hw "
> >> - "watchpoint.\n");
> >> - continue_flag = 0;
> >> - }
> >> - /* Check target signal */
> >> - if (record_full_list->u.end.sigval != GDB_SIGNAL_0)
> >> - /* FIXME: better way to check */
> >> - continue_flag = 0;
> >> - }
> >> + continue_flag = 0;
> >> }
> >>
> >> - if (continue_flag)
> >> + if (record_full_stop_reason
> >> + == TARGET_STOPPED_BY_WATCHPOINT)
> >> {
> >> - if (execution_direction == EXEC_REVERSE)
> >> - {
> >> - if (record_full_list->prev)
> >> - record_full_list = record_full_list->prev;
> >> - }
> >> - else
> >> - {
> >> - if (record_full_list->next)
> >> - record_full_list = record_full_list->next;
> >> - }
> >> + if (record_debug)
> >> + gdb_printf (gdb_stdlog,
> >> + "Process record: hit hw "
> >> + "watchpoint.\n");
> >> + continue_flag = 0;
> >> }
> >> + if (record_full_list[record_full_next_insn].sigval.has_value ())
> >> + continue_flag = 0;
> >> +
> >> + if (execution_direction == EXEC_REVERSE)
> >> + record_full_next_insn--;
> >> + else
> >> + record_full_next_insn++;
> >> }
> >> while (continue_flag);
> >>
> >> + if (record_full_next_insn < 0)
> >> + {
> >> + gdb_assert (execution_direction == EXEC_REVERSE);
> >> + record_full_next_insn = 0;
> >> + }
> >> + else if (record_full_next_insn > record_full_list.size ())
> >> + {
> >> + gdb_assert (execution_direction == EXEC_FORWARD);
> >> + record_full_next_insn = record_full_list.size ();
> >> + }
> >> + /* Reset the current instruciton to point to the one to be replayed
> > Nit: instruction
> >
> >> + moving forward. */
> >> + else if (execution_direction == EXEC_REVERSE)
> >> + record_full_next_insn++;
> >> +
> >> replay_out:
> >> if (status->kind () == TARGET_WAITKIND_STOPPED)
> >> {
> >> + int insn = (execution_direction == EXEC_FORWARD)
> >> + ? record_full_next_insn - 1 : record_full_next_insn;
> >> if (record_full_get_sig)
> >> status->set_stopped (GDB_SIGNAL_INT);
> >> - else if (record_full_list->u.end.sigval != GDB_SIGNAL_0)
> >> - /* FIXME: better way to check */
> >> - status->set_stopped (record_full_list->u.end.sigval);
> >> + else if (record_full_list[insn].sigval.has_value ())
> >> + status->set_stopped
> >> + (record_full_list[insn].sigval.value ());
> >> else
> >> status->set_stopped (GDB_SIGNAL_TRAP);
> >> }
> >> @@ -1464,12 +1346,9 @@ record_full_wait_1 (struct target_ops *ops,
> >> catch (const gdb_exception &ex)
> >> {
> >> if (execution_direction == EXEC_REVERSE)
> >> - {
> >> - if (record_full_list->next)
> >> - record_full_list = record_full_list->next;
> >> - }
> >> + record_full_next_insn++;
> >> else
> >> - record_full_list = record_full_list->prev;
> >> + record_full_next_insn--;
> >>
> >> throw;
> >> }
> >> @@ -1557,8 +1436,7 @@ record_full_registers_change (struct regcache
> >> *regcache, int regnum)
> >> /* Check record_full_insn_num. */
> >> record_full_check_insn_num ();
> >>
> >> - record_full_arch_list_head = NULL;
> >> - record_full_arch_list_tail = NULL;
> >> + record_full_reset_incomplete ();
> >>
> >> if (regnum < 0)
> >> {
> >> @@ -1568,7 +1446,7 @@ record_full_registers_change (struct regcache
> >> *regcache, int regnum)
> >> {
> >> if (record_full_arch_list_add_reg (regcache, i))
> >> {
> >> - record_full_list_release (record_full_arch_list_tail);
> >> + record_full_reset_incomplete ();
> >> error (_("Process record: failed to record execution log."));
> >> }
> >> }
> >> @@ -1577,18 +1455,11 @@ record_full_registers_change (struct
> regcache
> >> *regcache, int regnum)
> >> {
> >> if (record_full_arch_list_add_reg (regcache, regnum))
> >> {
> >> - record_full_list_release (record_full_arch_list_tail);
> >> + record_full_reset_incomplete ();
> >> error (_("Process record: failed to record execution log."));
> >> }
> >> }
> >> - if (record_full_arch_list_add_end ())
> >> - {
> >> - record_full_list_release (record_full_arch_list_tail);
> >> - error (_("Process record: failed to record execution log."));
> >> - }
> >> - record_full_list->next = record_full_arch_list_head;
> >> - record_full_arch_list_head->prev = record_full_list;
> >> - record_full_list = record_full_arch_list_tail;
> >> + record_full_save_instruction ();
> >>
> >> if (record_full_insn_num == record_full_insn_max_num)
> >> record_full_list_release_first ();
> >> @@ -1607,7 +1478,7 @@ record_full_target::store_registers (struct
> >> regcache *regcache, int regno)
> >> {
> >> int n;
> >>
> >> - /* Let user choose if he wants to write register or not. */
> >> + /* Let user choose if they want to write register or not. */
> >> if (regno < 0)
> >> n =
> >> query (_("Because GDB is in replay mode, changing the "
> >> @@ -1642,7 +1513,7 @@ record_full_target::store_registers (struct
> >> regcache *regcache, int regno)
> >> }
> >>
> >> /* Destroy the record from here forward. */
> >> - record_full_list_release_following (record_full_list);
> >> + record_full_list_release_following (record_full_next_insn);
> >> }
> >>
> >> record_full_registers_change (regcache, regno);
> >> @@ -1675,36 +1546,24 @@ record_full_target::xfer_partial (enum
> >> target_object object,
> >> error (_("Process record canceled the operation."));
> >>
> >> /* Destroy the record from here forward. */
> >> - record_full_list_release_following (record_full_list);
> >> + record_full_list_release_following (record_full_next_insn);
> >> }
> >>
> >> /* Check record_full_insn_num */
> >> record_full_check_insn_num ();
> >>
> >> /* Record registers change to list as an instruction. */
> >> - record_full_arch_list_head = NULL;
> >> - record_full_arch_list_tail = NULL;
> >> + record_full_reset_incomplete ();
> >> if (record_full_arch_list_add_mem (offset, len))
> >> {
> >> - record_full_list_release (record_full_arch_list_tail);
> >> + record_full_reset_incomplete ();
> >> if (record_debug)
> >> gdb_printf (gdb_stdlog,
> >> "Process record: failed to record "
> >> "execution log.");
> >> return TARGET_XFER_E_IO;
> >> }
> >> - if (record_full_arch_list_add_end ())
> >> - {
> >> - record_full_list_release (record_full_arch_list_tail);
> >> - if (record_debug)
> >> - gdb_printf (gdb_stdlog,
> >> - "Process record: failed to record "
> >> - "execution log.");
> >> - return TARGET_XFER_E_IO;
> >> - }
> >> - record_full_list->next = record_full_arch_list_head;
> >> - record_full_arch_list_head->prev = record_full_list;
> >> - record_full_list = record_full_arch_list_tail;
> >> + record_full_save_instruction ();
> >>
> >> if (record_full_insn_num == record_full_insn_max_num)
> >> record_full_list_release_first ();
> >> @@ -1866,8 +1725,7 @@ record_full_base_target::get_bookmark (const
> char
> >> *args, int from_tty)
> >> char *ret = NULL;
> >>
> >> /* Return stringified form of instruction count. */
> >> - if (record_full_list && record_full_list->type == record_full_end)
> >> - ret = xstrdup (pulongest (record_full_list->u.end.insn_num));
> >> + ret = xstrdup (pulongest
> (record_full_list[record_full_next_insn].insn_num));
> > I think we can get here with an empty record_full_list - in case we are in
> recording mode,
> > no instructions have been logged and this function is called:
> >
> > ~~~
> > (gdb) info record
> > Active record target: record-full
> > Record mode:
> > No instructions have been logged.
> > Max logged instructions is 200000.
> > (gdb) bookmark
> >
> > Thread 1 "gdb-up" hit Breakpoint 1, record_full_base_target::get_bookmark
> (this=0x555558392900 <record_full_ops>, args=0x0, from_tty=1) at
> /tmp/record-full.c:1774
> > 1774 char *ret = NULL;
> > (gdb) p record_full_next_insn
> > $1 = 0
> > (gdb) p record_full_list.empty ()
> > $2 = true
> > ~~~
I wonder, do we somewhere have a test for bookmarks?
I also find a specific description for this in the manual... what's the difference to checkpoints?
I am a bit confused about the bookmark feature (of course, this is nothing to fix for this series...).
> >> if (record_debug)
> >> {
> >> @@ -1923,30 +1781,22 @@ record_full_base_target::record_method
> (ptid_t
> >> ptid)
> >> void
> >> record_full_base_target::info_record ()
> >> {
> >> - struct record_full_entry *p;
> >> -
> >> if (RECORD_FULL_IS_REPLAY)
> >> gdb_printf (_("Replay mode:\n"));
> >> else
> >> gdb_printf (_("Record mode:\n"));
> >>
> >> - /* Find entry for first actual instruction in the log. */
> >> - for (p = record_full_first.next;
> >> - p != NULL && p->type != record_full_end;
> >> - p = p->next)
> >> - ;
> >> -
> >> /* Do we have a log at all? */
> >> - if (p != NULL && p->type == record_full_end)
> >> + if (!record_full_list.empty ())
> >> {
> >> /* Display instruction number for first instruction in the log. */
> >> - gdb_printf (_("Lowest recorded instruction number is %s.\n"),
> >> - pulongest (p->u.end.insn_num));
> >> + gdb_printf (_("Lowest recorded instruction number is %u.\n"),
> >> + record_full_list[0].insn_num);
> >>
> >> /* If in replay mode, display where we are in the log. */
> >> if (RECORD_FULL_IS_REPLAY)
> >> - gdb_printf (_("Current instruction number is %s.\n"),
> >> - pulongest (record_full_list->u.end.insn_num));
> >> + gdb_printf (_("Current instruction number is %u.\n"),
> >> + record_full_list[record_full_next_insn].insn_num);
> >>
> >> /* Display instruction number for last instruction in the log. */
> >> gdb_printf (_("Highest recorded instruction number is %s.\n"),
> >> @@ -1975,7 +1825,7 @@
> record_full_base_target::supports_delete_record ()
> >> void
> >> record_full_base_target::delete_record ()
> >> {
> >> - record_full_list_release_following (record_full_list);
> >> + record_full_reset_history ();
> >> }
> >>
> >> /* The "record_is_replaying" target method. */
> >> @@ -2001,23 +1851,23 @@ record_full_base_target::record_will_replay
> >> (ptid_t ptid, int dir)
> >> /* Go to a specific entry. */
> >>
> >> static void
> >> -record_full_goto_entry (struct record_full_entry *p)
> >> +record_full_goto_entry (size_t target_insn)
> >> {
> >> - if (p == NULL)
> >> + if (target_insn >= record_full_list.size ())
> >> error (_("Target insn not found."));
> >> - else if (p == record_full_list)
> >> + else if (target_insn == record_full_next_insn)
> >> error (_("Already at target insn."));
> >> - else if (p->u.end.insn_num > record_full_list->u.end.insn_num)
> >> + else if (target_insn > record_full_next_insn)
> >> {
> >> gdb_printf (_("Go forward to insn number %s\n"),
> >> - pulongest (p->u.end.insn_num));
> >> - record_full_goto_insn (p, EXEC_FORWARD);
> >> + pulongest (record_full_list[target_insn].insn_num));
> >> + record_full_goto_insn (target_insn, EXEC_FORWARD);
> >> }
> >> else
> >> {
> >> gdb_printf (_("Go backward to insn number %s\n"),
> >> - pulongest (p->u.end.insn_num));
> >> - record_full_goto_insn (p, EXEC_REVERSE);
> >> + pulongest (target_insn));
> >> + record_full_goto_insn (target_insn, EXEC_REVERSE);
> >> }
> >>
> >> registers_changed ();
> >> @@ -2033,13 +1883,7 @@ record_full_goto_entry (struct
> record_full_entry
> >> *p)
> >> void
> >> record_full_base_target::goto_record_begin ()
> >> {
> >> - struct record_full_entry *p = NULL;
> >> -
> >> - for (p = &record_full_first; p != NULL; p = p->next)
> >> - if (p->type == record_full_end)
> >> - break;
> >> -
> >> - record_full_goto_entry (p);
> >> + record_full_goto_entry (0);
> >> }
> >>
> >> /* The "goto_record_end" target method. */
> >> @@ -2047,15 +1891,7 @@ record_full_base_target::goto_record_begin ()
> >> void
> >> record_full_base_target::goto_record_end ()
> >> {
> >> - struct record_full_entry *p = NULL;
> >> -
> >> - for (p = record_full_list; p->next != NULL; p = p->next)
> >> - ;
> >> - for (; p!= NULL; p = p->prev)
> >> - if (p->type == record_full_end)
> >> - break;
> >> -
> >> - record_full_goto_entry (p);
> >> + record_full_goto_entry (record_full_list.size () -1);
> > Nit: whitespace before 1 => "record_full_list.size () - 1"
> >
> > And in case the record_full_list is empty, won't we call
> > record_full_goto_entry with an invalid value for target_insn ?
> >
> >> }
> >>
> >> /* The "goto_record" target method. */
> >> @@ -2063,13 +1899,7 @@ record_full_base_target::goto_record_end ()
> >> void
> >> record_full_base_target::goto_record (ULONGEST target_insn)
> >> {
> >> - struct record_full_entry *p = NULL;
> >> -
> >> - for (p = &record_full_first; p != NULL; p = p->next)
> >> - if (p->type == record_full_end && p->u.end.insn_num == target_insn)
> >> - break;
> >> -
> >> - record_full_goto_entry (p);
> >> + record_full_goto_entry (target_insn);
> >> }
> >>
> >> /* The "record_stop_replaying" target method. */
> >> @@ -2339,19 +2169,96 @@ netorder32 (uint32_t input)
> >> return ret;
> >> }
> >>
> >> +static void
> >> +record_full_read_entry_from_bfd (bfd *cbfd, asection *osec, int
> *bfd_offset)
> >> +{
> >> + uint8_t rectype;
> >> + uint32_t regnum, len;
> >> + uint64_t addr;
> >> + regcache *cache = get_thread_regcache (inferior_thread ());
> >> +
> >> + bfdcore_read (cbfd, osec, &rectype, sizeof (rectype), bfd_offset);
> >> + switch (rectype)
> >> + {
> >> + case record_full_reg: /* reg */
> >> + {
> >> + /* Get register number to regnum. */
> >> + bfdcore_read (cbfd, osec, ®num, sizeof (regnum), bfd_offset);
> >> + regnum = netorder32 (regnum);
> >> +
> >> + record_full_entry rec;
> >> +
> >> + rec = record_full_reg_init (cache, regnum);
> >> +
> >> + /* Get val. */
> >> + bfdcore_read (cbfd, osec, record_full_get_loc (&rec),
> >> + rec.u.reg.len, bfd_offset);
> >> +
> >> + if (record_debug)
> >> + gdb_printf (gdb_stdlog,
> >> + " Reading register %d (1 "
> >> + "plus %lu plus %d bytes)\n",
> >> + rec.u.reg.num,
> >> + (unsigned long) sizeof (regnum),
> >> + rec.u.reg.len);
> >> +
> >> + record_full_arch_list_add (rec);
> >> + break;
> >> + }
> >> +
> >> + case record_full_mem: /* mem */
> >> + {
> >> + /* Get len. */
> >> + bfdcore_read (cbfd, osec, &len, sizeof (len), bfd_offset);
> >> + len = netorder32 (len);
> >> +
> >> + /* Get addr. */
> >> + bfdcore_read (cbfd, osec, &addr, sizeof (addr),
> >> + bfd_offset);
> >> + addr = netorder64 (addr);
> >> +
> >> + record_full_entry rec;
> >> + rec = record_full_mem_init (addr, len);
> >> +
> >> + /* Get val. */
> >> + bfdcore_read (cbfd, osec, record_full_get_loc (&rec), len,
> >> + bfd_offset);
> >> +
> >> + if (record_debug)
> >> + gdb_printf (gdb_stdlog,
> >> + " Reading memory %s (1 plus "
> >> + "%lu plus %lu plus %d bytes)\n",
> >> + paddress (get_current_arch (),
> >> + rec.u.mem.addr),
> >> + (unsigned long) sizeof (addr),
> >> + (unsigned long) sizeof (len),
> >> + len);
> >> +
> >> + record_full_arch_list_add (rec);
> >> + break;
> >> + }
> >> +
> >> + default:
> >> + error (_("Bad entry type %d, offset %d of %lu in core file %ps."),
> >> + rectype, *bfd_offset, bfd_section_size (osec),
> >> + styled_string (file_name_style.style (),
> >> + bfd_get_filename (cbfd)));
> >> + break;
> >> + }
> >> +}
> >> +
> >> /* Restore the execution log from core file CBFD. */
> >>
> >> static void
> >> record_full_restore (struct bfd &cbfd)
> >> {
> >> uint32_t magic;
> >> - struct record_full_entry *rec;
> >> asection *osec;
> >> uint32_t osec_size;
> >> int bfd_offset = 0;
> >>
> >> /* "record_full_restore" can only be called when record list is empty. */
> >> - gdb_assert (record_full_first.next == NULL);
> >> + gdb_assert (record_full_list.empty ());
> >>
> >> if (record_debug)
> >> gdb_printf (gdb_stdlog, "Restoring recording from core file.\n");
> >> @@ -2379,124 +2286,47 @@ record_full_restore (struct bfd &cbfd)
> >> "RECORD_FULL_FILE_MAGIC (0x%s)\n",
> >> phex_nz (netorder32 (magic), 4));
> >>
> >> - /* Restore the entries in recfd into record_full_arch_list_head and
> >> - record_full_arch_list_tail. */
> >> - record_full_arch_list_head = NULL;
> >> - record_full_arch_list_tail = NULL;
> >> record_full_insn_num = 0;
> >>
> >> try
> >> {
> >> - regcache *regcache = get_thread_regcache (inferior_thread ());
> >> -
> >> - while (1)
> >> + while (bfd_offset < osec_size)
> >> {
> >> - uint8_t rectype;
> >> - uint32_t regnum, len, signal, count;
> >> - uint64_t addr;
> >> -
> >> - /* We are finished when offset reaches osec_size. */
> >> - if (bfd_offset >= osec_size)
> >> - break;
> >> - bfdcore_read (&cbfd, osec, &rectype, sizeof (rectype), &bfd_offset);
> >> -
> >> - switch (rectype)
> >> + record_full_reset_incomplete ();
> >> + uint32_t eff_count = 0;
> >> + uint8_t sigval;
> >> + uint32_t insn_num;
> >> +
> >> + /* First read the generic information for an instruction. */
> >> + bfdcore_read (&cbfd, osec, &sigval, sizeof (uint8_t), &bfd_offset);
> >> + bfdcore_read (&cbfd, osec, &eff_count, sizeof (uint32_t),
> >> + &bfd_offset);
> >> + bfdcore_read (&cbfd, osec, &insn_num, sizeof (uint32_t),
> >> + &bfd_offset);
> >> +
> >> + record_full_incomplete_instruction.insn_num = netorder32
> >> (insn_num);
> >> + if (sigval != GDB_SIGNAL_0)
> >> + record_full_incomplete_instruction.sigval = (gdb_signal) sigval;
> >> +
> >> + eff_count = netorder32 (eff_count);
> >> +
> >> + /* This deals with all the side effects. */
> >> + while (eff_count > 0)
> >> {
> > There is one space too much indent.
> >
> >> - case record_full_reg: /* reg */
> >> - /* Get register number to regnum. */
> >> - bfdcore_read (&cbfd, osec, ®num, sizeof (regnum),
> >> - &bfd_offset);
> >> - regnum = netorder32 (regnum);
> >> -
> >> - rec = record_full_reg_alloc (regcache, regnum);
> >> -
> >> - /* Get val. */
> >> - bfdcore_read (&cbfd, osec, record_full_get_loc (rec),
> >> - rec->u.reg.len, &bfd_offset);
> >> -
> >> - if (record_debug)
> >> - gdb_printf (gdb_stdlog,
> >> - " Reading register %d (1 "
> >> - "plus %lu plus %d bytes)\n",
> >> - rec->u.reg.num,
> >> - (unsigned long) sizeof (regnum),
> >> - rec->u.reg.len);
> >> - break;
> >> + eff_count--;
> >>
> >> - case record_full_mem: /* mem */
> >> - /* Get len. */
> >> - bfdcore_read (&cbfd, osec, &len, sizeof (len), &bfd_offset);
> >> - len = netorder32 (len);
> >> -
> >> - /* Get addr. */
> >> - bfdcore_read (&cbfd, osec, &addr, sizeof (addr), &bfd_offset);
> >> - addr = netorder64 (addr);
> >> -
> >> - rec = record_full_mem_alloc (addr, len);
> >> -
> >> - /* Get val. */
> >> - bfdcore_read (&cbfd, osec, record_full_get_loc (rec),
> >> - rec->u.mem.len, &bfd_offset);
> >> -
> >> - if (record_debug)
> >> - gdb_printf (gdb_stdlog,
> >> - " Reading memory %s (1 plus "
> >> - "%lu plus %lu plus %d bytes)\n",
> >> - paddress (get_current_arch (),
> >> - rec->u.mem.addr),
> >> - (unsigned long) sizeof (addr),
> >> - (unsigned long) sizeof (len),
> >> - rec->u.mem.len);
> >> - break;
> >> -
> >> - case record_full_end: /* end */
> >> - rec = record_full_end_alloc ();
> >> - record_full_insn_num ++;
> >> -
> >> - /* Get signal value. */
> >> - bfdcore_read (&cbfd, osec, &signal, sizeof (signal),
> >> - &bfd_offset);
> >> - signal = netorder32 (signal);
> >> - rec->u.end.sigval = (enum gdb_signal) signal;
> >> -
> >> - /* Get insn count. */
> >> - bfdcore_read (&cbfd, osec, &count, sizeof (count), &bfd_offset);
> >> - count = netorder32 (count);
> >> - rec->u.end.insn_num = count;
> >> - record_full_insn_count = count + 1;
> >> - if (record_debug)
> >> - gdb_printf (gdb_stdlog,
> >> - " Reading record_full_end (1 + "
> >> - "%lu + %lu bytes), offset == %s\n",
> >> - (unsigned long) sizeof (signal),
> >> - (unsigned long) sizeof (count),
> >> - paddress (get_current_arch (),
> >> - bfd_offset));
> >> - break;
> >> -
> >> - default:
> >> - error (_("Bad entry type in core file %ps."),
> >> - styled_string (file_name_style.style (),
> >> - bfd_get_filename (&cbfd)));
> >> - break;
> >> + record_full_read_entry_from_bfd (&cbfd, osec, &bfd_offset);
> >> }
> >>
> >> - /* Add rec to record arch list. */
> >> - record_full_arch_list_add (rec);
> >> + record_full_save_instruction ();
> >> }
> >> }
> >> catch (const gdb_exception &ex)
> >> {
> >> - record_full_list_release (record_full_arch_list_tail);
> >> + record_full_reset_incomplete ();
> >> throw;
> >> }
> >>
> >> - /* Add record_full_arch_list_head to the end of record list. */
> >> - record_full_first.next = record_full_arch_list_head;
> >> - record_full_arch_list_head->prev = &record_full_first;
> >> - record_full_arch_list_tail->next = NULL;
> >> - record_full_list = &record_full_first;
> >> -
> >> /* Update record_full_insn_max_num. */
> >> if (record_full_insn_num > record_full_insn_max_num)
> >> {
> >> @@ -2505,6 +2335,10 @@ record_full_restore (struct bfd &cbfd)
> >> record_full_insn_max_num);
> >> }
> >>
> >> + /* When loading a recording, we'll always start at the oldest possible
> >> + instruction, no matter where the original recording was stopped. */
> >> + record_full_next_insn = 0;
> >> +
> >> /* Succeeded. */
> >> gdb_printf (_("Restored records from core file %s.\n"),
> >> bfd_get_filename (&cbfd));
> >> @@ -2538,13 +2372,73 @@ cmd_record_full_restore (const char *args,
> int
> >> from_tty)
> >> record_full_open (nullptr, from_tty);
> >> }
> >>
> >> +static void
> >> +record_full_write_entry_to_bfd (record_full_entry &entry,
> >> + gdb_bfd_ref_ptr obfd,
> >> + asection *osec, int *bfd_offset,
> >> + struct gdbarch *gdbarch)
> >> +{
> >> + /* Save entry. */
> >> + uint8_t type;
> >> + uint32_t regnum, len;
> >> + uint64_t addr;
> >> +
> >> + type = entry.type;
> >> + bfdcore_write (obfd.get (), osec, &type, sizeof (type), bfd_offset);
> >> +
> >> + switch (entry.type)
> >> + {
> >> + case record_full_reg: /* reg */
> >> + if (record_debug)
> >> + gdb_printf (gdb_stdlog,
> >> + " Writing register %d (1 "
> >> + "plus %lu plus %d bytes)\n",
> >> + entry.u.reg.num,
> >> + (unsigned long) sizeof (regnum),
> >> + entry.u.reg.len);
> >> +
> >> + /* Write regnum. */
> >> + regnum = netorder32 (entry.u.reg.num);
> >> + bfdcore_write (obfd.get (), osec, ®num, sizeof (regnum),
> bfd_offset);
> >> +
> >> + /* Write regval. */
> >> + bfdcore_write (obfd.get (), osec, record_full_get_loc (&entry),
> >> + entry.u.reg.len, bfd_offset);
> >> + break;
> >> +
> >> + case record_full_mem: /* mem */
> >> + if (record_debug)
> >> + gdb_printf (gdb_stdlog,
> >> + " Writing memory %s (1 plus "
> >> + "%lu plus %lu plus %d bytes)\n",
> >> + paddress (gdbarch,
> >> + entry.u.mem.addr),
> >> + (unsigned long) sizeof (addr),
> >> + (unsigned long) sizeof (len),
> >> + entry.u.mem.len);
> >> +
> >> + /* Write memlen. */
> >> + len = netorder32 (entry.u.mem.len);
> >> + bfdcore_write (obfd.get (), osec, &len, sizeof (len), bfd_offset);
> >> +
> >> + /* Write memaddr. */
> >> + addr = netorder64 (entry.u.mem.addr);
> >> + bfdcore_write (obfd.get (), osec, &addr, sizeof (addr), bfd_offset);
> >> +
> >> + /* Write memval. */
> >> + bfdcore_write (obfd.get (), osec, record_full_get_loc (&entry),
> >> + entry.u.mem.len, bfd_offset);
> >> + break;
> >> + }
> >> +
> >> +}
> >> +
> >> /* Save the execution log to a file. We use a modified elf corefile
> >> format, with an extra section for our data. */
> >>
> >> void
> >> record_full_base_target::save_record (const char *recfilename)
> >> {
> >> - struct record_full_entry *cur_record_full_list;
> >> uint32_t magic;
> >> struct gdbarch *gdbarch;
> >> int save_size = 0;
> >> @@ -2562,9 +2456,6 @@ record_full_base_target::save_record (const
> char
> >> *recfilename)
> >> /* Arrange to remove the output file on failure. */
> >> gdb::unlinker unlink_file (recfilename);
> >>
> >> - /* Save the current record entry to "cur_record_full_list". */
> >> - cur_record_full_list = record_full_list;
> >> -
> >> /* Get the values of regcache and gdbarch. */
> >> regcache *regcache = get_thread_regcache (inferior_thread ());
> >> gdbarch = regcache->arch ();
> >> @@ -2574,34 +2465,27 @@ record_full_base_target::save_record (const
> >> char *recfilename)
> >> = record_full_gdb_operation_disable_set ();
> >>
> >> /* Reverse execute to the begin of record list. */
> >> - while (1)
> >> - {
> >> - /* Check for beginning and end of log. */
> >> - if (record_full_list == &record_full_first)
> >> - break;
> >> -
> >> - record_full_exec_insn (regcache, gdbarch, record_full_list);
> >> -
> >> - if (record_full_list->prev)
> >> - record_full_list = record_full_list->prev;
> >> - }
> >> + for (int i = record_full_next_insn - 1; i >= 0; i--)
> >> + record_full_exec_insn (regcache, gdbarch,
> >> + record_full_list[i]);
> >>
> >> /* Compute the size needed for the extra bfd section. */
> >> save_size = 4; /* magic cookie */
> >> - for (record_full_list = record_full_first.next; record_full_list;
> >> - record_full_list = record_full_list->next)
> >> - switch (record_full_list->type)
> >> - {
> >> - case record_full_end:
> >> - save_size += 1 + 4 + 4;
> >> - break;
> >> - case record_full_reg:
> >> - save_size += 1 + 4 + record_full_list->u.reg.len;
> >> - break;
> >> - case record_full_mem:
> >> - save_size += 1 + 4 + 8 + record_full_list->u.mem.len;
> >> - break;
> >> - }
> >> + for (int i = record_full_list.size () - 1; i >= 0; i--)
> >> + {
> >> + /* Number of effects of an instruction. */
> >> + save_size += sizeof (uint32_t) + sizeof (uint8_t) + sizeof (uint32_t);
> >> + for (auto &entry : record_full_list[i].effects)
> >> + switch (entry.type)
> >> + {
> >> + case record_full_reg:
> >> + save_size += 1 + 4 + entry.u.reg.len;
> >> + break;
> >> + case record_full_mem:
> >> + save_size += 1 + 4 + 8 + entry.u.mem.len;
> >> + break;
> >> + }
> >> + }
> >>
> >> /* Make the new bfd section. */
> >> osec = bfd_make_section_anyway_with_flags (obfd.get (), "precord",
> >> @@ -2630,108 +2514,32 @@ record_full_base_target::save_record
> (const
> >> char *recfilename)
> >>
> >> /* Save the entries to recfd and forward execute to the end of
> >> record list. */
> >> - record_full_list = &record_full_first;
> >> - while (1)
> >> + for (int i = 0; i < record_full_list.size (); i++)
> >> {
> >> - /* Save entry. */
> >> - if (record_full_list != &record_full_first)
> >> + uint32_t eff_count = (uint32_t) record_full_list[i].effects.size ();
> >> + uint32_t insn_num = record_full_list[i].insn_num;
> >> + uint8_t sigval = (record_full_list[i].sigval.has_value ())
> >> + ? record_full_list[i].sigval.value ()
> >> + : GDB_SIGNAL_0;
> >> +
> >> + /* Signal. */
> >> + bfdcore_write (obfd.get (), osec, &sigval, sizeof (sigval), &bfd_offset);
> >> + eff_count = netorder32 (eff_count);
> >> + /* Number of effects. */
> >> + bfdcore_write (obfd.get (), osec, &eff_count, sizeof (eff_count),
> >> + &bfd_offset);
> >> + /* Instruction number. */
> >> + bfdcore_write (obfd.get (), osec, &insn_num, sizeof (uint32_t),
> >> + &bfd_offset);
> >> +
> >> + for (auto &entry : record_full_list[i].effects)
> >> {
> >> - uint8_t type;
> >> - uint32_t regnum, len, signal, count;
> >> - uint64_t addr;
> >> -
> >> - type = record_full_list->type;
> >> - bfdcore_write (obfd.get (), osec, &type, sizeof (type), &bfd_offset);
> >> -
> >> - switch (record_full_list->type)
> >> - {
> >> - case record_full_reg: /* reg */
> >> - if (record_debug)
> >> - gdb_printf (gdb_stdlog,
> >> - " Writing register %d (1 "
> >> - "plus %lu plus %d bytes)\n",
> >> - record_full_list->u.reg.num,
> >> - (unsigned long) sizeof (regnum),
> >> - record_full_list->u.reg.len);
> >> -
> >> - /* Write regnum. */
> >> - regnum = netorder32 (record_full_list->u.reg.num);
> >> - bfdcore_write (obfd.get (), osec, ®num,
> >> - sizeof (regnum), &bfd_offset);
> >> -
> >> - /* Write regval. */
> >> - bfdcore_write (obfd.get (), osec,
> >> - record_full_get_loc (record_full_list),
> >> - record_full_list->u.reg.len, &bfd_offset);
> >> - break;
> >> -
> >> - case record_full_mem: /* mem */
> >> - if (record_debug)
> >> - gdb_printf (gdb_stdlog,
> >> - " Writing memory %s (1 plus "
> >> - "%lu plus %lu plus %d bytes)\n",
> >> - paddress (gdbarch,
> >> - record_full_list->u.mem.addr),
> >> - (unsigned long) sizeof (addr),
> >> - (unsigned long) sizeof (len),
> >> - record_full_list->u.mem.len);
> >> -
> >> - /* Write memlen. */
> >> - len = netorder32 (record_full_list->u.mem.len);
> >> - bfdcore_write (obfd.get (), osec, &len, sizeof (len),
> >> - &bfd_offset);
> >> -
> >> - /* Write memaddr. */
> >> - addr = netorder64 (record_full_list->u.mem.addr);
> >> - bfdcore_write (obfd.get (), osec, &addr,
> >> - sizeof (addr), &bfd_offset);
> >> -
> >> - /* Write memval. */
> >> - bfdcore_write (obfd.get (), osec,
> >> - record_full_get_loc (record_full_list),
> >> - record_full_list->u.mem.len, &bfd_offset);
> >> - break;
> >> -
> >> - case record_full_end:
> >> - if (record_debug)
> >> - gdb_printf (gdb_stdlog,
> >> - " Writing record_full_end (1 + "
> >> - "%lu + %lu bytes)\n",
> >> - (unsigned long) sizeof (signal),
> >> - (unsigned long) sizeof (count));
> >> - /* Write signal value. */
> >> - signal = netorder32 (record_full_list->u.end.sigval);
> >> - bfdcore_write (obfd.get (), osec, &signal,
> >> - sizeof (signal), &bfd_offset);
> >> -
> >> - /* Write insn count. */
> >> - count = netorder32 (record_full_list->u.end.insn_num);
> >> - bfdcore_write (obfd.get (), osec, &count,
> >> - sizeof (count), &bfd_offset);
> >> - break;
> >> - }
> >> + record_full_write_entry_to_bfd (entry, obfd, osec, &bfd_offset,
> >> + gdbarch);
> >> }
> >> -
> >> /* Execute entry. */
> >> - record_full_exec_insn (regcache, gdbarch, record_full_list);
> >> -
> >> - if (record_full_list->next)
> >> - record_full_list = record_full_list->next;
> >> - else
> >> - break;
> >> - }
> >> -
> >> - /* Reverse execute to cur_record_full_list. */
> >> - while (1)
> >> - {
> >> - /* Check for beginning and end of log. */
> >> - if (record_full_list == cur_record_full_list)
> >> - break;
> >> -
> >> - record_full_exec_insn (regcache, gdbarch, record_full_list);
> >> -
> >> - if (record_full_list->prev)
> >> - record_full_list = record_full_list->prev;
> >> + if (i < record_full_next_insn)
> >> + record_full_exec_insn (regcache, gdbarch, record_full_list[i]);
> >> }
> >>
> >> unlink_file.keep ();
> >> @@ -2746,7 +2554,7 @@ record_full_base_target::save_record (const
> char
> >> *recfilename)
> >> correspondingly. */
> >>
> >> static void
> >> -record_full_goto_insn (struct record_full_entry *entry,
> >> +record_full_goto_insn (size_t target_insn,
> >> enum exec_direction_kind dir)
> > You could explain the new parameter in the function description.
> >
> >> {
> >> scoped_restore restore_operation_disable
> >> @@ -2757,17 +2565,12 @@ record_full_goto_insn (struct
> record_full_entry
> >> *entry,
> >> /* Assume everything is valid: we will hit the entry,
> >> and we will not hit the end of the recording. */
> >>
> >> - if (dir == EXEC_FORWARD)
> >> - record_full_list = record_full_list->next;
> >> -
> >> - do
> >> - {
> >> - record_full_exec_insn (regcache, gdbarch, record_full_list);
> >> - if (dir == EXEC_REVERSE)
> >> - record_full_list = record_full_list->prev;
> >> - else
> >> - record_full_list = record_full_list->next;
> >> - } while (record_full_list != entry);
> >> + if (dir == EXEC_REVERSE)
> >> + for (int i = record_full_next_insn; i > target_insn; i--)
> >> + record_full_exec_insn (regcache, gdbarch, record_full_list[i - 1]);
> >> + else
> >> + for (int i = record_full_next_insn; i < target_insn; i++)
> >> + record_full_exec_insn (regcache, gdbarch, record_full_list[i]);
> >> }
> >>
> >> /* Alias for "target record-full". */
> >> @@ -2798,61 +2601,36 @@ set_record_full_insn_max_num (const char
> >> *args, int from_tty,
> >> static void
> >> maintenance_print_record_instruction (const char *args, int from_tty)
> >> {
> >> - struct record_full_entry *to_print = record_full_list;
> >> + if (record_full_list.empty ())
> >> + error (_("Not enough recorded history"));
> >>
> >> + int offset = record_full_next_insn - 1;
> >> + /* Reduce the offset by 1 if the record_full_next_insn is after the end
> >> + so that we show the last recorded instruction instead of crashing. */
> >> + if (offset == record_full_list.size ())
> >> + offset--;
> >> if (args != nullptr)
> >> {
> >> - int offset = value_as_long (parse_and_eval (args));
> >> - if (offset > 0)
> >> - {
> >> - /* Move forward OFFSET instructions. We know we found the
> >> - end of an instruction when to_print->type is record_full_end. */
> >> - while (to_print->next != nullptr && offset > 0)
> >> - {
> >> - to_print = to_print->next;
> >> - if (to_print->type == record_full_end)
> >> - offset--;
> >> - }
> >> - if (offset != 0)
> >> - error (_("Not enough recorded history"));
> >> - }
> >> - else
> >> - {
> >> - while (to_print->prev != nullptr && offset < 0)
> >> - {
> >> - to_print = to_print->prev;
> >> - if (to_print->type == record_full_end)
> >> - offset++;
> >> - }
> >> - if (offset != 0)
> >> - error (_("Not enough recorded history"));
> >> - }
> >> + offset += value_as_long (parse_and_eval (args));
> >> + if (offset >= record_full_list.size () || offset < 0)
> >> + error (_("Not enough recorded history"));
> >> }
> >> - gdb_assert (to_print != nullptr);
> >> + auto to_print = record_full_list.begin () + offset;
> >>
> >> gdbarch *arch = current_inferior ()->arch ();
> >>
> >> - /* Go back to the start of the instruction. */
> >> - while (to_print->prev != nullptr && to_print->prev->type !=
> record_full_end)
> >> - to_print = to_print->prev;
> >> -
> >> - /* if we're in the first record, there are no actual instructions
> >> - recorded. Warn the user and leave. */
> >> - if (to_print == &record_full_first)
> >> - error (_("Not enough recorded history"));
> >> -
> >> - while (to_print->type != record_full_end)
> >> + for (auto entry : to_print->effects)
> >> {
> >> - switch (to_print->type)
> >> + switch (entry.type)
> >> {
> >> case record_full_reg:
> >> {
> >> - type *regtype = gdbarch_register_type (arch, to_print-
> >>> u.reg.num);
> >> + type *regtype = gdbarch_register_type (arch, entry.u.reg.num);
> >> value *val
> >> = value_from_contents (regtype,
> >> - record_full_get_loc (to_print));
> >> + record_full_get_loc (&entry));
> >> gdb_printf ("Register %s changed: ",
> >> - gdbarch_register_name (arch, to_print-
> >>> u.reg.num));
> >> + gdbarch_register_name (arch, entry.u.reg.num));
> >> struct value_print_options opts;
> >> get_user_print_options (&opts);
> >> opts.raw = true;
> >> @@ -2862,17 +2640,16 @@ maintenance_print_record_instruction
> (const
> >> char *args, int from_tty)
> >> }
> >> case record_full_mem:
> >> {
> >> - gdb_byte *b = record_full_get_loc (to_print);
> >> + gdb_byte *b = record_full_get_loc (&entry);
> >> gdb_printf ("%d bytes of memory at address %s changed from:",
> >> - to_print->u.mem.len,
> >> - print_core_address (arch, to_print->u.mem.addr));
> >> - for (int i = 0; i < to_print->u.mem.len; i++)
> >> + entry.u.mem.len,
> >> + print_core_address (arch, entry.u.mem.addr));
> >> + for (int i = 0; i < entry.u.mem.len; i++)
> >> gdb_printf (" %02x", b[i]);
> >> gdb_printf ("\n");
> >> break;
> >> }
> >> }
> >> - to_print = to_print->next;
> >> }
> >> }
> >>
> >> @@ -2880,11 +2657,6 @@ INIT_GDB_FILE (record_full)
> >> {
> >> struct cmd_list_element *c;
> >>
> >> - /* Init record_full_first. */
> >> - record_full_first.prev = NULL;
> >> - record_full_first.next = NULL;
> >> - record_full_first.type = record_full_end;
> >> -
> >> add_target (record_full_target_info, record_full_open);
> >> add_deprecated_target_alias (record_full_target_info, "record");
> >> add_target (record_full_core_target_info, record_full_open);
> >> diff --git a/gdb/record-full.h b/gdb/record-full.h
> >> index 51effe74560..c327d879a8a 100644
> >> --- a/gdb/record-full.h
> >> +++ b/gdb/record-full.h
> >> @@ -41,7 +41,6 @@ enum record_result
> >>
> >> extern int record_full_arch_list_add_reg (struct regcache *regcache, int
> >> num);
> >> extern int record_full_arch_list_add_mem (CORE_ADDR addr, int len);
> >> -extern int record_full_arch_list_add_end (void);
> >>
> >> /* Returns true if the process record target is open. */
> >> extern int record_full_is_used (void);
> >> diff --git a/gdb/riscv-tdep.c b/gdb/riscv-tdep.c
> >> index 6b5c9c02d46..f5b1f66844c 100644
> >> --- a/gdb/riscv-tdep.c
> >> +++ b/gdb/riscv-tdep.c
> >> @@ -5466,8 +5466,5 @@ riscv_process_record (struct gdbarch *gdbarch,
> >> struct regcache *regcache,
> >> if (res != RECORD_SUCCESS)
> >> return res;
> >>
> >> - if (record_full_arch_list_add_end ())
> >> - return -1;
> >> -
> >> return 0;
> >> }
> >> diff --git a/gdb/rs6000-tdep.c b/gdb/rs6000-tdep.c
> >> index e135df94a40..f964889a49f 100644
> >> --- a/gdb/rs6000-tdep.c
> >> +++ b/gdb/rs6000-tdep.c
> >> @@ -7138,8 +7138,6 @@ ppc_process_prefix_instruction (int insn_prefix,
> int
> >> insn_suffix,
> >> if (record_full_arch_list_add_reg (regcache, PPC_PC_REGNUM))
> >> return -1;
> >>
> >> - if (record_full_arch_list_add_end ())
> >> - return -1;
> >> return 0;
> >> }
> >>
> >> @@ -7447,8 +7445,6 @@ ppc_process_record (struct gdbarch *gdbarch,
> >> struct regcache *regcache,
> >>
> >> if (record_full_arch_list_add_reg (regcache, PPC_PC_REGNUM))
> >> return -1;
> >> - if (record_full_arch_list_add_end ())
> >> - return -1;
> >> return 0;
> >> }
> >>
> >> diff --git a/gdb/s390-linux-tdep.c b/gdb/s390-linux-tdep.c
> >> index 3cd6b359d13..6bea30f08dc 100644
> >> --- a/gdb/s390-linux-tdep.c
> >> +++ b/gdb/s390-linux-tdep.c
> >> @@ -910,9 +910,6 @@ s390_linux_record_signal (struct gdbarch
> *gdbarch,
> >> struct regcache *regcache,
> >> if (record_full_arch_list_add_mem (sp, sizeof_rt_sigframe))
> >> return -1;
> >>
> >> - if (record_full_arch_list_add_end ())
> >> - return -1;
> >> -
> >> return 0;
> >> }
> >>
> >> diff --git a/gdb/s390-tdep.c b/gdb/s390-tdep.c
> >> index f9d7bdd04e4..36ce659ea15 100644
> >> --- a/gdb/s390-tdep.c
> >> +++ b/gdb/s390-tdep.c
> >> @@ -7019,8 +7019,6 @@ s390_process_record (struct gdbarch *gdbarch,
> >> struct regcache *regcache,
> >>
> >> if (record_full_arch_list_add_reg (regcache, S390_PSWA_REGNUM))
> >> return -1;
> >> - if (record_full_arch_list_add_end ())
> >> - return -1;
> >> return 0;
> >> }
> >>
> >> --
> >> 2.53.0
> >>
> > Kind Regards,
> > Christina
> >
> > Intel Deutschland GmbH
> > Registered Address: Dornacher Strasse 1, 85622 Feldkirchen, Germany
> > Tel: +49 89 991 430, www.intel.de
> > Managing Directors: Harry Demas, Jeffrey Schneiderman, Yin Chong Sorrell
> > Chairperson of the Supervisory Board: Nicole Lau
> > Registered Seat: Munich
> > Commercial Register: Amtsgericht Muenchen HRB 186928
> >
Christina
Intel Deutschland GmbH
Registered Address: Dornacher Strasse 1, 85622 Feldkirchen, Germany
Tel: +49 89 991 430, www.intel.de
Managing Directors: Harry Demas, Jeffrey Schneiderman, Yin Chong Sorrell
Chairperson of the Supervisory Board: Nicole Lau
Registered Seat: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928
^ permalink raw reply [flat|nested] 19+ messages in thread
* Re: [PATCH v2 1/6] gdb/record: Refactor record history
2026-05-11 15:23 ` Schimpe, Christina
@ 2026-05-12 18:50 ` Guinevere Larsen
2026-05-13 7:54 ` Schimpe, Christina
0 siblings, 1 reply; 19+ messages in thread
From: Guinevere Larsen @ 2026-05-12 18:50 UTC (permalink / raw)
To: Schimpe, Christina, gdb-patches
On 5/11/26 12:23 PM, Schimpe, Christina wrote:
> Hi Guinevere,
>
> Please find some further comments below.
Hi Christina!
Thanks again for taking such a detailed look at this patch! I have some
inlined comments, thanks for finding these issues!
>> -----Original Message-----
>> From: Guinevere Larsen <guinevere@redhat.com>
>> Sent: Donnerstag, 7. Mai 2026 19:38
>> To: Schimpe, Christina <christina.schimpe@intel.com>; gdb-
>> patches@sourceware.org
>> Subject: Re: [PATCH v2 1/6] gdb/record: Refactor record history
>>
>> On 5/6/26 6:16 PM, Schimpe, Christina wrote:
>>> Hi Guinevere,
>>>
>>> Thank you for working on this.
>>> I found two items that might be worth looking at in more detail, but
>>> apart from that it’s mostly minor nits. Please find my feedback below.
>>>
>>> I don’t have much experience with the record feature, so my review is
>>> a bit slow here. To fully understand this patch, I probably need more time,
>>> but I wanted to share the comments I already have. Sorry for chiming in
>>> so late. I’ll try again tomorrow, or by Friday at the latest.
>> Hi! Thank you for noting all the inconsistencies, I'll fix almost all of
>> them before pushing!
>>
>> The one thing I don't think it's a good idea is to make the change from
>> record_full_list -> record_full_log in this commit... mostly because it
>> will introduce untold amounts of rebase conflicts. I'll introduce a
>> following commit to this series that will make that renaming, though :)
>> --
>> Cheers,
>> Guinevere Larsen
>> It/she
>>
>>>> -----Original Message-----
>>>> From: Guinevere Larsen <guinevere@redhat.com>
>>>> Sent: Donnerstag, 23. April 2026 17:26
>>>> To: gdb-patches@sourceware.org
>>>> Cc: Guinevere Larsen <guinevere@redhat.com>
>>>> Subject: [PATCH v2 1/6] gdb/record: Refactor record history
>>>>
>>>> This is the first step in a large refactor in how GDB keeps execution
>>>> history. Rather than using a linked list where multiple entries can
>>>> describe a single instruction, the history will now be stored in an
>>>> std::deque, each instruction being one entry in the deque.
>>>>
>>>> The choice was initially to use an std::vector, but it would become
>>>> unwieldy because it needs all the memory to be consecutive, which is
>>>> hard for 200 thousand entries. Deque was picked because it was a nice
>>>> midpoint between vector (maximum cache cohesion) and linked list
>>>> (maximum ease of finding space to store more).
>>>>
>>>> Each instruction in memory will be now one record_full_instruction
>>>> entry, which for this commit just contains a vector of
>>>> record_full_entry for the effects of the instruction, and the data that
>>>> was stored in the record_full_end entry (that is, the instruction number
>>>> and the signal, if any).
>>>>
>>>> This change introduced a minimal performance improvement (what's
>>>> important is that it isn't a degradation) and a reduction in the total
>>>> memory footprint of roughly 20% if the entire history is used.
>>>> ---
>>>> gdb/aarch64-tdep.c | 2 -
>>>> gdb/amd64-linux-tdep.c | 3 -
>>>> gdb/arm-tdep.c | 2 -
>>>> gdb/i386-linux-tdep.c | 3 -
>>>> gdb/i386-tdep.c | 4 -
>>>> gdb/loongarch-tdep.c | 2 -
>>>> gdb/moxie-tdep.c | 2 -
>>>> gdb/ppc-linux-tdep.c | 3 -
>>>> gdb/record-full.c | 1180 ++++++++++++++++------------------------
>>>> gdb/record-full.h | 1 -
>>>> gdb/riscv-tdep.c | 3 -
>>>> gdb/rs6000-tdep.c | 4 -
>>>> gdb/s390-linux-tdep.c | 3 -
>>>> gdb/s390-tdep.c | 2 -
>>>> 14 files changed, 476 insertions(+), 738 deletions(-)
>>>>
>>>> diff --git a/gdb/aarch64-tdep.c b/gdb/aarch64-tdep.c
>>>> index 4befaa2720d..a532992b1d8 100644
>>>> --- a/gdb/aarch64-tdep.c
>>>> +++ b/gdb/aarch64-tdep.c
>>>> @@ -6210,8 +6210,6 @@ aarch64_process_record (struct gdbarch
>> *gdbarch,
>>>> struct regcache *regcache,
>>>> aarch64_record.aarch64_mems[rec_no].len))
>>>> ret = -1;
>>>>
>>>> - if (record_full_arch_list_add_end ())
>>>> - ret = -1;
>>>> }
>>>>
>>>> deallocate_reg_mem (&aarch64_record);
>>>> diff --git a/gdb/amd64-linux-tdep.c b/gdb/amd64-linux-tdep.c
>>>> index a5ac26654cf..9b23db72bbe 100644
>>>> --- a/gdb/amd64-linux-tdep.c
>>>> +++ b/gdb/amd64-linux-tdep.c
>>>> @@ -1591,9 +1591,6 @@ amd64_linux_record_signal (struct gdbarch
>>>> *gdbarch,
>>>> + AMD64_LINUX_frame_size))
>>>> return -1;
>>>>
>>>> - if (record_full_arch_list_add_end ())
>>>> - return -1;
>>>> -
>>>> return 0;
>>>> }
>>>>
>>>> diff --git a/gdb/arm-tdep.c b/gdb/arm-tdep.c
>>>> index 08cce9dbad8..1ce0927f26b 100644
>>>> --- a/gdb/arm-tdep.c
>>>> +++ b/gdb/arm-tdep.c
>>>> @@ -14911,8 +14911,6 @@ arm_process_record (struct gdbarch
>> *gdbarch,
>>>> struct regcache *regcache,
>>>> }
>>>> }
>>>>
>>>> - if (record_full_arch_list_add_end ())
>>>> - ret = -1;
>>>> }
>>>>
>>>>
>>>> diff --git a/gdb/i386-linux-tdep.c b/gdb/i386-linux-tdep.c
>>>> index 23aeccac9fc..4f33766fcdd 100644
>>>> --- a/gdb/i386-linux-tdep.c
>>>> +++ b/gdb/i386-linux-tdep.c
>>>> @@ -949,9 +949,6 @@ i386_linux_record_signal (struct gdbarch
>> *gdbarch,
>>>> I386_LINUX_xstate +
>>>> I386_LINUX_frame_size))
>>>> return -1;
>>>>
>>>> - if (record_full_arch_list_add_end ())
>>>> - return -1;
>>>> -
>>>> return 0;
>>>> }
>>>>
>>>>
>>>> diff --git a/gdb/i386-tdep.c b/gdb/i386-tdep.c
>>>> index fa935b5fcdb..fee36b46a73 100644
>>>> --- a/gdb/i386-tdep.c
>>>> +++ b/gdb/i386-tdep.c
>>>> @@ -5201,8 +5201,6 @@ i386_record_vex (struct i386_record_s *ir,
>> uint8_t
>>>> vex_w, uint8_t vex_r,
>>>> }
>>>>
>>>> record_full_arch_list_add_reg (ir->regcache, ir-
>>>>> regmap[X86_RECORD_REIP_REGNUM]);
>>>> - if (record_full_arch_list_add_end ())
>>>> - return -1;
>>>>
>>>> return 0;
>>>> }
>>>> @@ -8359,8 +8357,6 @@ Do you want to stop the program?"),
>>>>
>>>> /* In the future, maybe still need to deal with need_dasm. */
>>>> I386_RECORD_FULL_ARCH_LIST_ADD_REG
>> (X86_RECORD_REIP_REGNUM);
>>>> - if (record_full_arch_list_add_end ())
>>>> - return -1;
>>>>
>>>> return 0;
>>>>
>>>> diff --git a/gdb/loongarch-tdep.c b/gdb/loongarch-tdep.c
>>>> index 225b1abb703..5ec6b2a48d0 100644
>>>> --- a/gdb/loongarch-tdep.c
>>>> +++ b/gdb/loongarch-tdep.c
>>>> @@ -2789,8 +2789,6 @@ loongarch_process_record (struct gdbarch
>>>> *gdbarch, struct regcache *regcache,
>>>> LOONGARCH_PC_REGNUM))
>>>> return -1;
>>>>
>>>> - if (record_full_arch_list_add_end ())
>>>> - return -1;
>>>> }
>>>>
>>>> return ret;
>>>> diff --git a/gdb/moxie-tdep.c b/gdb/moxie-tdep.c
>>>> index c8a04d21f59..2f8f0186488 100644
>>>> --- a/gdb/moxie-tdep.c
>>>> +++ b/gdb/moxie-tdep.c
>>>> @@ -1040,8 +1040,6 @@ moxie_process_record (struct gdbarch
>> *gdbarch,
>>>> struct regcache *regcache,
>>>>
>>>> if (record_full_arch_list_add_reg (regcache, MOXIE_PC_REGNUM))
>>>> return -1;
>>>> - if (record_full_arch_list_add_end ())
>>>> - return -1;
>>>> return 0;
>>>> }
>>>>
>>>> diff --git a/gdb/ppc-linux-tdep.c b/gdb/ppc-linux-tdep.c
>>>> index 19698eaacbe..e2f53551709 100644
>>>> --- a/gdb/ppc-linux-tdep.c
>>>> +++ b/gdb/ppc-linux-tdep.c
>>>> @@ -1565,9 +1565,6 @@ ppc_linux_record_signal (struct gdbarch
>> *gdbarch,
>>>> struct regcache *regcache,
>>>> if (record_full_arch_list_add_mem (sp, SIGNAL_FRAMESIZE +
>>>> sizeof_rt_sigframe))
>>>> return -1;
>>>>
>>>> - if (record_full_arch_list_add_end ())
>>>> - return -1;
>>>> -
>>>> return 0;
>>>> }
>>>>
>>>> diff --git a/gdb/record-full.c b/gdb/record-full.c
>>>> index 69d2c100e57..aac69cee17e 100644
>>>> --- a/gdb/record-full.c
>>>> +++ b/gdb/record-full.c
>>> I think we should include vector, optional and deque directly.
>>>
>>>> @@ -72,20 +72,17 @@
>>>> #define DEFAULT_RECORD_FULL_INSN_MAX_NUM 200000
>>>>
>>>> #define RECORD_FULL_IS_REPLAY \
>>>> - (record_full_list->next || ::execution_direction == EXEC_REVERSE)
>>>> + ( (record_full_next_insn != record_full_list.size ()) \
>>> Nit: No whitespace after the first bracket:
>>> => ((record_full_next_insn != record_full_list.size ()) \
>>>
>>>> + || ::execution_direction == EXEC_REVERSE)
>>>>
>>>> #define RECORD_FULL_FILE_MAGIC netorder32(0x20091016)
>>>>
>>>> /* These are the core structs of the process record functionality.
>>>>
>>>> A record_full_entry is a record of the value change of a register
>>>> - ("record_full_reg") or a part of memory ("record_full_mem"). And each
>>>> - instruction must have a struct record_full_entry ("record_full_end")
>>>> - that indicates that this is the last struct record_full_entry of this
>>>> - instruction.
>>>> -
>>>> - Each struct record_full_entry is linked to "record_full_list" by "prev"
>>>> - and "next" pointers. */
>>>> + ("record_full_reg") or a part of memory ("record_full_mem").
>>>> + These are saved on the record_full_instruction struct, which also
>>>> + contains some extra information, such as delivered signals. */
>>>>
>>>> struct record_full_mem_entry
>>>> {
>>>> @@ -112,47 +109,14 @@ struct record_full_reg_entry
>>>> } u;
>>>> };
>>>>
>>>> -struct record_full_end_entry
>>>> -{
>>>> - enum gdb_signal sigval;
>>>> - ULONGEST insn_num;
>>>> -};
>>>> -
>>>> enum record_full_type
>>>> {
>>>> - record_full_end = 0,
>>>> record_full_reg,
>>>> record_full_mem
>>>> };
>>>>
>>>> -/* This is the data structure that makes up the execution log.
>>>> -
>>>> - The execution log consists of a single linked list of entries
>>>> - of type "struct record_full_entry". It is doubly linked so that it
>>>> - can be traversed in either direction.
>>>> -
>>>> - The start of the list is anchored by a struct called
>>>> - "record_full_first". The pointer "record_full_list" either points
>>>> - to the last entry that was added to the list (in record mode), or to
>>>> - the next entry in the list that will be executed (in replay mode).
>>>> -
>>>> - Each list element (struct record_full_entry), in addition to next
>>>> - and prev pointers, consists of a union of three entry types: mem,
>>>> - reg, and end. A field called "type" determines which entry type is
>>>> - represented by a given list element.
>>>> -
>>>> - Each instruction that is added to the execution log is represented
>>>> - by a variable number of list elements ('entries'). The instruction
>>>> - will have one "reg" entry for each register that is changed by
>>>> - executing the instruction (including the PC in every case). It
>>>> - will also have one "mem" entry for each memory change. Finally,
>>>> - each instruction will have an "end" entry that separates it from
>>>> - the changes associated with the next instruction. */
>>>> -
>>>> struct record_full_entry
>>>> {
>>>> - struct record_full_entry *prev;
>>>> - struct record_full_entry *next;
>>>> enum record_full_type type;
>>>> union
>>>> {
>>>> @@ -160,11 +124,31 @@ struct record_full_entry
>>>> struct record_full_reg_entry reg;
>>>> /* mem */
>>>> struct record_full_mem_entry mem;
>>>> - /* end */
>>>> - struct record_full_end_entry end;
>>>> } u;
>>>> };
>>>>
>>>> +/* This is the main structure that comprises the execution log.
>>>> + Each instruction is comprised of:
>>>> + * The instruction number: How many instructions were recorded before
>>>> + this one;
>>>> + * sigval: Whether the inferior received a signal while the following
>>>> + instruction was being recorded;
> It might be worth describing in the comment in which cases this does not
> have a value, to point out the reason why this is now optional.
> As I understand it before this patch we used GDB_SIGNAL_0 for this case, is that right?
well, yeah, we used to use GDB_SIGNAL_0, but I think it is better to
explicitly say "there was no signal" other than say "the signal was 0"
which is treated as a nothing. It's the problem with NULL/nullptr,
versus languages where nullptrs aren't allowed and instead accessing an
unset pointer is just disallowed. I just want to add more mindful usage
of it to make code safer.
So I don't think it makes sense to add in a comment why it changed, when
we instead needed a comment earlier about how to deal with "no signal
was delivered"
>
>>>> + * effects: A list of record_full_entry structures, each of which
>>>> + describing one effect that the instruction has on the inferior.
>>>> +
>>>> + Note, the signal is stored in the previous instruction for historical
>>>> + reasons. This is how it was first implemented, and no one has gotten
>>>> + around to changing it yet. */
>>>> +
>>>> +struct record_full_instruction
>>>> +{
>>>> + /* This might be different from the index if
>>>> + we had to remove the first few instructions. */
>>>> + uint32_t insn_num;
>>>> + std::optional<gdb_signal> sigval;
>>>> + std::vector<record_full_entry> effects;
>>>> +};
>>>> +
>>>> /* If true, query if PREC cannot record memory
>>>> change of next instruction. */
>>>> bool record_full_memory_query = false;
>>>> @@ -181,27 +165,25 @@ static detached_regcache
>>>> *record_full_core_regbuf = NULL;
>>>> static std::vector<target_section> record_full_core_sections;
>>>> static struct record_full_core_buf_entry *record_full_core_buf_list =
>> NULL;
>>>> -/* The following variables are used for managing the linked list that
>>>> - represents the execution log.
>>>> +/* The following variables are used for managing the history of executed
>>>> + instructions from the inferior.
>>>>
>>>> - record_full_first is the anchor that holds down the beginning of
>>>> - the list.
>>>> + record_full_list contains all instructions that were fully executed and
>>>> + saved to the log, so that we can replay the execution.
>>>>
>>>> - record_full_list serves two functions:
>>>> - 1) In record mode, it anchors the end of the list.
>>>> - 2) In replay mode, it traverses the list and points to
>>>> - the next instruction that must be emulated.
>>>> + record_full_next_insn always points to the next instruction that would
>>>> + be executed if the inferior executes forward. In the special case when
>>>> + the inferior is not replaying, record_full_next_insn points past the
>>>> + end of the history.
>>>>
>>>> - record_full_arch_list_head and record_full_arch_list_tail are used
>>>> - to manage a separate list, which is used to build up the change
>>>> - elements of the currently executing instruction during record mode.
>>>> - When this instruction has been completely annotated in the "arch
>>>> - list", it will be appended to the main execution log. */
>>>> + record_full_incomplete_instruction holds a partial instruction, while
>>>> + the lower target is disassembling the instruction, or as partial xfers are
>>>> + happening. It is manipulated by the "arch list" functions for historical
>>>> + reasons. */
>>>>
>>>> -static struct record_full_entry record_full_first;
>>>> -static struct record_full_entry *record_full_list = &record_full_first;
>>>> -static struct record_full_entry *record_full_arch_list_head = NULL;
>>>> -static struct record_full_entry *record_full_arch_list_tail = NULL;
>>>> +static std::deque<record_full_instruction> record_full_list;
>>> Given that this is not a list anymore I wonder if we should better call this
>> sth. like
>>> record_full_history or record_full_log or even simply
>> recorded_instructions?
>>>> +static record_full_instruction record_full_incomplete_instruction;
>>>> +int record_full_next_insn;
> Any particular reason why this is not static?
no, I'll make that change.
>
>>>> /* true ask user. false auto delete the last struct record_full_entry. */
>>>> static bool record_full_stop_at_limit = true;
>>>> @@ -361,6 +343,14 @@ record_full_target::kill ()
>>>> record_kill (this);
>>>> }
>>>>
>>>> +static void
>>>> +record_full_reset_incomplete ()
>>>> +{
>>>> + record_full_incomplete_instruction.effects.clear ();
>>>> + record_full_incomplete_instruction.sigval.reset ();
>>>> + record_full_incomplete_instruction.insn_num = 0;
>>>> +}
>>>> +
>>>> /* See record-full.h. */
>>>>
>>>> int
>>>> @@ -390,156 +380,120 @@ static struct cmd_list_element
>>>> *show_record_full_cmdlist;
>>>> /* Command list for "record full". */
>>>> static struct cmd_list_element *record_full_cmdlist;
>>>>
>>>> -static void record_full_goto_insn (struct record_full_entry *entry,
>>>> +static void record_full_goto_insn (size_t target_insn,
>>>> enum exec_direction_kind dir);
>>>>
>>>> -/* Alloc and free functions for record_full_reg, record_full_mem, and
>>>> - record_full_end entries. */
>>>> +/* Initialization and cleanup functions for record_full_reg and
>>>> + record_full_mem entries. */
>>>>
>>>> -/* Alloc a record_full_reg record entry. */
>>>> +/* Init a record_full_reg record entry. */
>>>>
>>>> -static inline struct record_full_entry *
>>>> -record_full_reg_alloc (struct regcache *regcache, int regnum)
>>>> +static inline struct record_full_entry
>>>> +record_full_reg_init (struct regcache *regcache, int regnum)
>>>> {
>>>> - struct record_full_entry *rec;
>>>> + struct record_full_entry rec;
>>>> struct gdbarch *gdbarch = regcache->arch ();
>>>>
>>>> - rec = XCNEW (struct record_full_entry);
>>>> - rec->type = record_full_reg;
>>>> - rec->u.reg.num = regnum;
>>>> - rec->u.reg.len = register_size (gdbarch, regnum);
>>>> - if (rec->u.reg.len > sizeof (rec->u.reg.u.buf))
>>>> - rec->u.reg.u.ptr = (gdb_byte *) xmalloc (rec->u.reg.len);
>>>> + rec.type = record_full_reg;
>>>> + rec.u.reg.num = regnum;
>>>> + rec.u.reg.len = register_size (gdbarch, regnum);
>>>> + if (rec.u.reg.len > sizeof (rec.u.reg.u.buf))
>>>> + rec.u.reg.u.ptr = (gdb_byte *) xmalloc (rec.u.reg.len);
>>>>
>>>> return rec;
>>>> }
>>>>
>>>> -/* Free a record_full_reg record entry. */
>>>> +/* Cleanup a record_full_reg record entry. */
>>>>
>>>> static inline void
>>>> -record_full_reg_release (struct record_full_entry *rec)
>>>> +record_full_reg_cleanup (struct record_full_entry rec)
>>>> {
>>>> - gdb_assert (rec->type == record_full_reg);
>>>> - if (rec->u.reg.len > sizeof (rec->u.reg.u.buf))
>>>> - xfree (rec->u.reg.u.ptr);
>>>> - xfree (rec);
>>>> + gdb_assert (rec.type == record_full_reg);
>>>> + if (rec.u.reg.len > sizeof (rec.u.reg.u.buf))
>>>> + xfree (rec.u.reg.u.ptr);
>>>> }
>>>>
>>>> -/* Alloc a record_full_mem record entry. */
>>>> +/* Init a record_full_mem record entry. */
>>>>
>>>> -static inline struct record_full_entry *
>>>> -record_full_mem_alloc (CORE_ADDR addr, int len)
>>>> +static inline struct record_full_entry
>>>> +record_full_mem_init (CORE_ADDR addr, int len)
>>>> {
>>>> - struct record_full_entry *rec;
>>>> + struct record_full_entry rec;
>>>>
>>>> - rec = XCNEW (struct record_full_entry);
>>>> - rec->type = record_full_mem;
>>>> - rec->u.mem.addr = addr;
>>>> - rec->u.mem.len = len;
>>>> - if (rec->u.mem.len > sizeof (rec->u.mem.u.buf))
>>>> - rec->u.mem.u.ptr = (gdb_byte *) xmalloc (len);
>>>> + rec.type = record_full_mem;
>>>> + rec.u.mem.addr = addr;
>>>> + rec.u.mem.len = len;
>>>> + if (rec.u.mem.len > sizeof (rec.u.mem.u.buf))
>>>> + rec.u.mem.u.ptr = (gdb_byte *) xmalloc (len);
>>>> + rec.u.mem.mem_entry_not_accessible = 0;
>>>>
>>>> return rec;
>>>> }
>>>>
>>>> -/* Free a record_full_mem record entry. */
>>>> +/* Cleanup a record_full_mem record entry. */
>>>>
>>>> static inline void
>>>> -record_full_mem_release (struct record_full_entry *rec)
>>>> -{
>>>> - gdb_assert (rec->type == record_full_mem);
>>>> - if (rec->u.mem.len > sizeof (rec->u.mem.u.buf))
>>>> - xfree (rec->u.mem.u.ptr);
>>>> - xfree (rec);
>>>> -}
>>>> -
>>>> -/* Alloc a record_full_end record entry. */
>>>> -
>>>> -static inline struct record_full_entry *
>>>> -record_full_end_alloc (void)
>>>> +record_full_mem_cleanup (struct record_full_entry rec)
>>>> {
>>>> - struct record_full_entry *rec;
>>>> -
>>>> - rec = XCNEW (struct record_full_entry);
>>>> - rec->type = record_full_end;
>>>> -
>>>> - return rec;
>>>> + gdb_assert (rec.type == record_full_mem);
>>>> + if (rec.u.mem.len > sizeof (rec.u.mem.u.buf))
>>>> + xfree (rec.u.mem.u.ptr);
>>>> }
>>>>
>>>> -/* Free a record_full_end record entry. */
>>>> +/* Free one record entry, any type. */
>>>>
>>>> static inline void
>>>> -record_full_end_release (struct record_full_entry *rec)
>>>> -{
>>>> - xfree (rec);
>>>> -}
>>>> -
>>>> -/* Free one record entry, any type.
>>>> - Return entry->type, in case caller wants to know. */
>>>> -
>>>> -static inline enum record_full_type
>>>> -record_full_entry_release (struct record_full_entry *rec)
>>>> +record_full_entry_cleanup (struct record_full_entry rec)
>>>> {
>>>> - enum record_full_type type = rec->type;
>>>>
>>>> - switch (type) {
>>>> + switch (rec.type) {
>>>> case record_full_reg:
>>>> - record_full_reg_release (rec);
>>>> + record_full_reg_cleanup (rec);
>>>> break;
>>>> case record_full_mem:
>>>> - record_full_mem_release (rec);
>>>> - break;
>>>> - case record_full_end:
>>>> - record_full_end_release (rec);
>>>> + record_full_mem_cleanup (rec);
>>>> break;
>>>> }
>>>> - return type;
>>>> }
>>>>
>>>> -/* Free all record entries in list pointed to by REC. */
>>>> -
>>>> static void
>>>> -record_full_list_release (struct record_full_entry *rec)
>>>> +record_full_reset_history ()
>>>> {
>>>> - if (!rec)
>>>> - return;
>>>> -
>>>> - while (rec->next)
>>>> - rec = rec->next;
>>>> + record_full_insn_num = 0;
>>>> + record_full_insn_count = 0;
>>>> + record_full_next_insn = 0;
>>>>
>>>> - while (rec->prev)
>>>> + for (auto &insn : record_full_list)
>>>> {
>>>> - rec = rec->prev;
>>>> - record_full_entry_release (rec->next);
>>>> + for (auto &entry : insn.effects)
>>>> + record_full_entry_cleanup (entry);
>>>> }
>>>>
>>>> - if (rec == &record_full_first)
>>>> - {
>>>> - record_full_insn_num = 0;
>>>> - record_full_first.next = NULL;
>>>> - }
>>>> - else
>>>> - record_full_entry_release (rec);
>>>> + record_full_list.clear ();
>>>> }
>>>>
>>>> -/* Free all record entries forward of the given list position. */
>>>> -
>>>> static void
>>>> -record_full_list_release_following (struct record_full_entry *rec)
>>>> +record_full_list_release_following (int index)
>>>> {
>>>> - struct record_full_entry *tmp = rec->next;
>>>> -
>>>> - rec->next = NULL;
>>>> - while (tmp)
>>>> + for (int i = record_full_list.size () - 1; i > index; i--)
>>>> {
>>>> - rec = tmp->next;
>>>> - if (record_full_entry_release (tmp) == record_full_end)
>>>> - {
>>>> - record_full_insn_num--;
>>>> - record_full_insn_count--;
>>>> - }
>>>> - tmp = rec;
>>>> + for (auto &entry : record_full_list[i].effects)
>>>> + record_full_entry_cleanup (entry);
>>>> + record_full_list.pop_back ();
>>>> }
>>>> + /* Set the next instruction to be past the end of the log so we
>>>> + start recording if the user moves forward again. */
>>>> + record_full_next_insn = index;
>>>> +}
>>>> +static void
>>>> +record_full_save_instruction ()
> A function comment would be nice.
>
>>>> +{
>>>> + ++record_full_insn_count;
>>>> + record_full_incomplete_instruction.insn_num = record_full_insn_count;
>>>> + record_full_incomplete_instruction.effects.shrink_to_fit ();
>>>> + record_full_list.push_back (record_full_incomplete_instruction);
> I think this line will at some point call the default copy constructor of record_full_mem_entry
> and record_full_reg_entry, which have those buffers:
>
> gdb_byte buf[sizeof (gdb_byte *)];
>
> IIUC you'll only have a shallow copy. Should we use a std::move instead here?
Might be worth, yeah...
>
> I further wonder if this problem might be related to the double free issues you
> describe in patch #3. Would you mind checking?
I did check it! When I was working on patch #3, I disabled copy
construction, only allowed move constructor/assignment because I
specifically thought that the vector push_back was the reason for the
double frees, but it still happened.
> And if you add the destructor, I think it would make sense to add a copy constructor etc., too:
> https://en.cppreference.com/cpp/language/rule_of_three
>
>>>> + record_full_next_insn++;
>>>> }
>>>>
>>>> /* Delete the first instruction from the beginning of the log, to make
>>>> @@ -550,52 +504,22 @@ record_full_list_release_following (struct
>>>> record_full_entry *rec)
>>>> static void
>>>> record_full_list_release_first (void)
>>>> {
>>>> - struct record_full_entry *tmp;
>>>> -
>>>> - if (!record_full_first.next)
>>>> + if (record_full_list.empty ())
>>>> return;
>>>>
>>>> - /* Loop until a record_full_end. */
>>>> - while (1)
>>>> - {
>>>> - /* Cut record_full_first.next out of the linked list. */
>>>> - tmp = record_full_first.next;
>>>> - record_full_first.next = tmp->next;
>>>> - tmp->next->prev = &record_full_first;
>>>> -
>>>> - /* tmp is now isolated, and can be deleted. */
>>>> - if (record_full_entry_release (tmp) == record_full_end)
>>>> - break; /* End loop at first record_full_end. */
>>>> + for (auto &entry : record_full_list[0].effects)
>>>> + record_full_entry_cleanup (entry);
>>>>
>>>> - if (!record_full_first.next)
>>>> - {
>>>> - gdb_assert (record_full_insn_num == 1);
>>>> - break; /* End loop when list is empty. */
>>>> - }
>>>> - }
>>>> + record_full_list.pop_front ();
>>>> + --record_full_next_insn;
>>>> }
>>>>
>>>> /* Add a struct record_full_entry to record_full_arch_list. */
>>>>
>>>> static void
>>>> -record_full_arch_list_add (struct record_full_entry *rec)
>>>> +record_full_arch_list_add (struct record_full_entry &rec)
>>>> {
>>>> - if (record_debug > 1)
>>>> - gdb_printf (gdb_stdlog,
>>>> - "Process record: record_full_arch_list_add %s.\n",
>>>> - host_address_to_string (rec));
>>>> -
>>>> - if (record_full_arch_list_tail)
>>>> - {
>>>> - record_full_arch_list_tail->next = rec;
>>>> - rec->prev = record_full_arch_list_tail;
>>>> - record_full_arch_list_tail = rec;
>>>> - }
>>>> - else
>>>> - {
>>>> - record_full_arch_list_head = rec;
>>>> - record_full_arch_list_tail = rec;
>>>> - }
>>>> + record_full_incomplete_instruction.effects.push_back (rec);
>>>> }
>>>>
>>>> /* Return the value storage location of a record entry. */
>>>> @@ -613,7 +537,6 @@ record_full_get_loc (struct record_full_entry *rec)
>>>> return rec->u.reg.u.ptr;
>>>> else
>>>> return rec->u.reg.u.buf;
>>>> - case record_full_end:
>>>> default:
>>>> gdb_assert_not_reached ("unexpected record_full_entry type");
>>>> return NULL;
>>>> @@ -625,7 +548,7 @@ record_full_get_loc (struct record_full_entry *rec)
>>>> int
>>>> record_full_arch_list_add_reg (struct regcache *regcache, int regnum)
>>>> {
>>>> - struct record_full_entry *rec;
>>>> + struct record_full_entry rec;
>>> I think we can omit the struct keyword here (there are some more
>> occurrences in this patch).
>>>> if (record_debug > 1)
>>>> gdb_printf (gdb_stdlog,
>>>> @@ -633,9 +556,9 @@ record_full_arch_list_add_reg (struct regcache
>>>> *regcache, int regnum)
>>>> "record list.\n",
>>>> regnum);
>>>>
>>>> - rec = record_full_reg_alloc (regcache, regnum);
>>>> + rec = record_full_reg_init (regcache, regnum);
>>>>
>>>> - regcache->cooked_read (regnum, record_full_get_loc (rec));
>>>> + regcache->cooked_read (regnum, record_full_get_loc (&rec));
>>>>
>>>> record_full_arch_list_add (rec);
>>>>
>>>> @@ -648,7 +571,7 @@ record_full_arch_list_add_reg (struct regcache
>>>> *regcache, int regnum)
>>>> int
>>>> record_full_arch_list_add_mem (CORE_ADDR addr, int len)
>>>> {
>>>> - struct record_full_entry *rec;
>>>> + struct record_full_entry rec;
>>>>
>>>> if (record_debug > 1)
>>>> gdb_printf (gdb_stdlog,
>>>> @@ -659,12 +582,12 @@ record_full_arch_list_add_mem (CORE_ADDR
>> addr,
>>>> int len)
>>>> if (!addr) /* FIXME: Why? Some arch must permit it... */
>>>> return 0;
>>>>
>>>> - rec = record_full_mem_alloc (addr, len);
>>>> + rec = record_full_mem_init (addr, len);
>>>>
>>>> if (record_read_memory (current_inferior ()->arch (), addr,
>>>> - record_full_get_loc (rec), len))
>>>> + record_full_get_loc (&rec), len))
>>>> {
>>>> - record_full_mem_release (rec);
>>>> + record_full_mem_cleanup (rec);
>>>> return -1;
>>>> }
>>>>
>>>> @@ -673,27 +596,6 @@ record_full_arch_list_add_mem (CORE_ADDR
>> addr,
>>>> int len)
>>>> return 0;
>>>> }
>>>>
>>>> -/* Add a record_full_end type struct record_full_entry to
>>>> - record_full_arch_list. */
>>>> -
>>>> -int
>>>> -record_full_arch_list_add_end (void)
>>>> -{
>>>> - struct record_full_entry *rec;
>>>> -
>>>> - if (record_debug > 1)
>>>> - gdb_printf (gdb_stdlog,
>>>> - "Process record: add end to arch list.\n");
>>>> -
>>>> - rec = record_full_end_alloc ();
>>>> - rec->u.end.sigval = GDB_SIGNAL_0;
>>>> - rec->u.end.insn_num = ++record_full_insn_count;
>>>> -
>>>> - record_full_arch_list_add (rec);
>>>> -
>>>> - return 0;
>>>> -}
>>>> -
>>>> static void
>>>> record_full_check_insn_num (void)
>>>> {
>>>> @@ -725,8 +627,7 @@ record_full_message (struct regcache *regcache,
>>>> enum gdb_signal signal)
>>>>
>>>> try
>>>> {
>>>> - record_full_arch_list_head = NULL;
>>>> - record_full_arch_list_tail = NULL;
>>>> + record_full_reset_incomplete ();
>>>>
>>>> /* Check record_full_insn_num. */
>>>> record_full_check_insn_num ();
>>>> @@ -746,20 +647,16 @@ record_full_message (struct regcache
>> *regcache,
>>>> enum gdb_signal signal)
>>>> the user says something different, like "deliver this signal"
>>>> during the replay mode).
>>>>
>>>> - User should understand that nothing he does during the replay
>>>> - mode will change the behavior of the child. If he tries,
>>>> + User should understand that nothing they do during the replay
>>>> + mode will change the behavior of the child. If they try,
>>>> then that is a user error.
>>>>
>>>> But we should still deliver the signal to gdb during the replay,
>>>> if we delivered it during the recording. Therefore we should
>>>> record the signal during record_full_wait, not
>>>> record_full_resume. */
>>>> - if (record_full_list != &record_full_first) /* FIXME better way
>>>> - to check */
>>>> - {
>>>> - gdb_assert (record_full_list->type == record_full_end);
>>>> - record_full_list->u.end.sigval = signal;
>>>> - }
>>>> + if (signal != GDB_SIGNAL_0)
>>>> + record_full_list[record_full_next_insn - 1].sigval = signal;
> Similar comment as already in my earlier review:
> Can record_full_next_insn be == 0 here or may record_full_list be empty ?
Oh you're right. This is probably because I misunderstood the order of
operations and was saving it to the current one, not the previous one,
and when I fixed that I forgot to check the original
>
> I think it might be worth checking the patch if there are more similar issues.
> The old patch had more guards to check this.
yeah good point, I'll look through the changes and see if I notice it
anywhere else.
>
> And I noticed in some other locations you cast it:
>
> if (sigval != GDB_SIGNAL_0)
> record_full_incomplete_instruction.sigval = (gdb_signal) sigval;
>
> Not sure if this is necessary or not, but it might be for checking and making it consistent?
I cast it in the other location because it is reading from the BFD and
so sigval is declared as uint8_t, not as gdb_signal.
> And is it intended that now we don't clear sigval anymore?
>
> Shouldn't we set it to std::nullopt in case signal == GDB_SIGNAL_0, to match the original
> behaviour?
yeah this is a mistake. The plan was that record_full_save_instruction
clears the incomplete instruction, but I apparently forgot that.
With that, it should always be clear so we won't need to explicitly set
it to nullopt.
I'll update the correct function.
>
>>>> if (signal == GDB_SIGNAL_0
>>>> || !gdbarch_process_record_signal_p (gdbarch))
>>>> @@ -778,13 +675,11 @@ record_full_message (struct regcache
>> *regcache,
>>>> enum gdb_signal signal)
>>>> }
>>>> catch (const gdb_exception &ex)
>>>> {
>>>> - record_full_list_release (record_full_arch_list_tail);
>>>> + record_full_reset_incomplete ();
>>>> throw;
>>>> }
>>>>
>>>> - record_full_list->next = record_full_arch_list_head;
>>>> - record_full_arch_list_head->prev = record_full_list;
>>>> - record_full_list = record_full_arch_list_tail;
>>>> + record_full_save_instruction ();
>>>>
>>>> if (record_full_insn_num == record_full_insn_max_num)
>>>> record_full_list_release_first ();
>>>> @@ -829,9 +724,9 @@ static enum target_stop_reason
>>>> record_full_stop_reason
>>>> entries and memory entries, followed by an 'end' entry. */
>>>>
>>>> static inline void
>>>> -record_full_exec_insn (struct regcache *regcache,
>>>> - struct gdbarch *gdbarch,
>>>> - struct record_full_entry *entry)
>>>> +record_full_exec_entry (struct regcache *regcache,
>>>> + struct gdbarch *gdbarch,
>>>> + struct record_full_entry *entry)
>>> Nit: omit struct keywords
>>> And there are some more places in this series/patch, but I will stop
>> commenting
>>> now on all of them.
>>>
>>>> {
>>>> switch (entry->type)
>>>> {
>>>> @@ -909,6 +804,15 @@ record_full_exec_insn (struct regcache
>> *regcache,
>>>> }
>>>> }
>>>>
>>>> +static inline void
>>>> +record_full_exec_insn (struct regcache *regcache,
>>>> + struct gdbarch *gdbarch,
>>>> + record_full_instruction &insn)
>>>> +{
>>>> + for (auto &entry : insn.effects)
>>>> + record_full_exec_entry (regcache, gdbarch, &entry);
>>>> +}
>>>> +
>>>> static void record_full_restore (struct bfd &cbfd);
>>>>
>>>> /* Asynchronous signal handle registered as event loop source for when
>>>> @@ -983,10 +887,7 @@ record_full_open (const char *args, int from_tty)
>>>> record_preopen ();
>>>>
>>>> /* Reset */
>>>> - record_full_insn_num = 0;
>>>> - record_full_insn_count = 0;
>>>> - record_full_list = &record_full_first;
>>>> - record_full_list->next = NULL;
>>>> + record_full_reset_history ();
>>>>
>>>> bfd *cbfd = get_inferior_core_bfd (current_inferior ());
>>>> if (cbfd != nullptr)
>>>> @@ -1014,7 +915,7 @@ record_full_base_target::close ()
>>>> if (record_debug)
>>>> gdb_printf (gdb_stdlog, "Process record: record_full_close\n");
>>>>
>>>> - record_full_list_release (record_full_list);
>>>> + record_full_reset_history ();
>>>>
>>>> /* Release record_full_core_regbuf. */
>>>> if (record_full_core_regbuf)
>>>> @@ -1313,7 +1214,6 @@ record_full_wait_1 (struct target_ops *ops,
>>>> struct gdbarch *gdbarch = regcache->arch ();
>>>> const address_space *aspace = current_inferior ()->aspace.get ();
>>>> int continue_flag = 1;
>>>> - int first_record_full_end = 1;
>>>>
>>>> try
>>>> {
>>>> @@ -1322,7 +1222,6 @@ record_full_wait_1 (struct target_ops *ops,
>>>> record_full_stop_reason = TARGET_STOPPED_BY_NO_REASON;
>>>> status->set_stopped (GDB_SIGNAL_0);
>>>>
>>>> - /* Check breakpoint when forward execute. */
>>>> if (execution_direction == EXEC_FORWARD)
>>>> {
>>>> tmp_pc = regcache_read_pc (regcache);
>>>> @@ -1330,8 +1229,7 @@ record_full_wait_1 (struct target_ops *ops,
>>>>
>>>> &record_full_stop_reason))
>>>> {
>>>> if (record_debug)
>>>> - gdb_printf (gdb_stdlog,
>>>> - "Process record: break at %s.\n",
>>>> + gdb_printf (gdb_stdlog, "Process record: break at %s.\n",
>>>> paddress (gdbarch, tmp_pc));
>>>> goto replay_out;
>>>> }
>>>> @@ -1344,10 +1242,10 @@ record_full_wait_1 (struct target_ops *ops,
>>>> the signal. */
>>>> target_terminal::ours ();
>>>>
>>>> - /* In EXEC_FORWARD mode, record_full_list points to the tail of
>> prev
>>>> - instruction. */
>>>> - if (execution_direction == EXEC_FORWARD && record_full_list-
>>> next)
>>>> - record_full_list = record_full_list->next;
>>>> + /* In EXEC_FORWARD mode, record_full_next_insn is the next
>>>> + instruction to be executed. */
>>>> + if (execution_direction == EXEC_REVERSE)
>>>> + record_full_next_insn--;
>>>>
>>>> /* Loop over the record_full_list, looking for the next place to
>>>> stop. */
>>>> @@ -1355,108 +1253,92 @@ record_full_wait_1 (struct target_ops *ops,
>>>> {
>>>> /* Check for beginning and end of log. */
>>>> if (execution_direction == EXEC_REVERSE
>>>> - && record_full_list == &record_full_first)
>>>> + && record_full_next_insn < 0)
>>>> {
>>>> /* Hit beginning of record log in reverse. */
>>>> status->set_no_history ();
>>>> + record_full_next_insn = 0;
>>>> break;
>>>> }
>>>> if (execution_direction != EXEC_REVERSE
>>>> - && !record_full_list->next)
>>>> + && record_full_next_insn == record_full_list.size ())
>>>> {
>>>> /* Hit end of record log going forward. */
>>>> status->set_no_history ();
>>>> break;
>>>> }
>>>>
>>>> - record_full_exec_insn (regcache, gdbarch, record_full_list);
>>>> + record_full_exec_insn
>>>> + (regcache, gdbarch,
>>>> + record_full_list[record_full_next_insn]);
>>>>
>>>> - if (record_full_list->type == record_full_end)
>>>> + /* step */
>>>> + if (record_full_resume_step)
>>>> {
>>>> if (record_debug > 1)
>>>> - gdb_printf
>>>> - (gdb_stdlog,
>>>> - "Process record: record_full_end %s to "
>>>> - "inferior.\n",
>>>> - host_address_to_string (record_full_list));
>>>> -
>>>> - if (first_record_full_end
>>>> - && execution_direction == EXEC_REVERSE)
>>>> - {
>>>> - /* When reverse execute, the first
>>>> - record_full_end is the part of current
>>>> - instruction. */
>>>> - first_record_full_end = 0;
>>>> - }
>>>> - else
>>>> - {
>>>> - /* In EXEC_REVERSE mode, this is the
>>>> - record_full_end of prev instruction. In
>>>> - EXEC_FORWARD mode, this is the
>>>> - record_full_end of current instruction. */
>>>> - /* step */
>>>> - if (record_full_resume_step)
>>>> - {
>>>> - if (record_debug > 1)
>>>> - gdb_printf (gdb_stdlog,
>>>> - "Process record: step.\n");
>>>> - continue_flag = 0;
>>>> - }
>>>> -
>>>> - /* check breakpoint */
>>>> - tmp_pc = regcache_read_pc (regcache);
>>>> - if (record_check_stopped_by_breakpoint
>>>> - (aspace, tmp_pc, &record_full_stop_reason))
>>>> - {
>>>> - if (record_debug)
>>>> - gdb_printf (gdb_stdlog,
>>>> - "Process record: break "
>>>> - "at %s.\n",
>>>> - paddress (gdbarch, tmp_pc));
>>>> + gdb_printf (gdb_stdlog,
>>>> + "Process record: step.\n");
>>>> + continue_flag = 0;
>>>> + }
>>>>
>>>> - continue_flag = 0;
>>>> - }
>>>> + /* check breakpoint */
>>>> + tmp_pc = regcache_read_pc (regcache);
>>>> + if (record_check_stopped_by_breakpoint
>>>> + (aspace, tmp_pc, &record_full_stop_reason))
>>>> + {
>>>> + if (record_debug)
>>>> + gdb_printf (gdb_stdlog,
>>>> + "Process record: break "
>>>> + "at %s.\n",
>>>> + paddress (gdbarch, tmp_pc));
>>>>
>>>> - if (record_full_stop_reason
>>>> - == TARGET_STOPPED_BY_WATCHPOINT)
>>>> - {
>>>> - if (record_debug)
>>>> - gdb_printf (gdb_stdlog,
>>>> - "Process record: hit hw "
>>>> - "watchpoint.\n");
>>>> - continue_flag = 0;
>>>> - }
>>>> - /* Check target signal */
>>>> - if (record_full_list->u.end.sigval != GDB_SIGNAL_0)
>>>> - /* FIXME: better way to check */
>>>> - continue_flag = 0;
>>>> - }
>>>> + continue_flag = 0;
>>>> }
>>>>
>>>> - if (continue_flag)
>>>> + if (record_full_stop_reason
>>>> + == TARGET_STOPPED_BY_WATCHPOINT)
>>>> {
>>>> - if (execution_direction == EXEC_REVERSE)
>>>> - {
>>>> - if (record_full_list->prev)
>>>> - record_full_list = record_full_list->prev;
>>>> - }
>>>> - else
>>>> - {
>>>> - if (record_full_list->next)
>>>> - record_full_list = record_full_list->next;
>>>> - }
>>>> + if (record_debug)
>>>> + gdb_printf (gdb_stdlog,
>>>> + "Process record: hit hw "
>>>> + "watchpoint.\n");
>>>> + continue_flag = 0;
>>>> }
>>>> + if (record_full_list[record_full_next_insn].sigval.has_value ())
>>>> + continue_flag = 0;
>>>> +
>>>> + if (execution_direction == EXEC_REVERSE)
>>>> + record_full_next_insn--;
>>>> + else
>>>> + record_full_next_insn++;
>>>> }
>>>> while (continue_flag);
>>>>
>>>> + if (record_full_next_insn < 0)
>>>> + {
>>>> + gdb_assert (execution_direction == EXEC_REVERSE);
>>>> + record_full_next_insn = 0;
>>>> + }
>>>> + else if (record_full_next_insn > record_full_list.size ())
>>>> + {
>>>> + gdb_assert (execution_direction == EXEC_FORWARD);
>>>> + record_full_next_insn = record_full_list.size ();
>>>> + }
>>>> + /* Reset the current instruciton to point to the one to be replayed
>>> Nit: instruction
>>>
>>>> + moving forward. */
>>>> + else if (execution_direction == EXEC_REVERSE)
>>>> + record_full_next_insn++;
>>>> +
>>>> replay_out:
>>>> if (status->kind () == TARGET_WAITKIND_STOPPED)
>>>> {
>>>> + int insn = (execution_direction == EXEC_FORWARD)
>>>> + ? record_full_next_insn - 1 : record_full_next_insn;
>>>> if (record_full_get_sig)
>>>> status->set_stopped (GDB_SIGNAL_INT);
>>>> - else if (record_full_list->u.end.sigval != GDB_SIGNAL_0)
>>>> - /* FIXME: better way to check */
>>>> - status->set_stopped (record_full_list->u.end.sigval);
>>>> + else if (record_full_list[insn].sigval.has_value ())
>>>> + status->set_stopped
>>>> + (record_full_list[insn].sigval.value ());
>>>> else
>>>> status->set_stopped (GDB_SIGNAL_TRAP);
>>>> }
>>>> @@ -1464,12 +1346,9 @@ record_full_wait_1 (struct target_ops *ops,
>>>> catch (const gdb_exception &ex)
>>>> {
>>>> if (execution_direction == EXEC_REVERSE)
>>>> - {
>>>> - if (record_full_list->next)
>>>> - record_full_list = record_full_list->next;
>>>> - }
>>>> + record_full_next_insn++;
>>>> else
>>>> - record_full_list = record_full_list->prev;
>>>> + record_full_next_insn--;
>>>>
>>>> throw;
>>>> }
>>>> @@ -1557,8 +1436,7 @@ record_full_registers_change (struct regcache
>>>> *regcache, int regnum)
>>>> /* Check record_full_insn_num. */
>>>> record_full_check_insn_num ();
>>>>
>>>> - record_full_arch_list_head = NULL;
>>>> - record_full_arch_list_tail = NULL;
>>>> + record_full_reset_incomplete ();
>>>>
>>>> if (regnum < 0)
>>>> {
>>>> @@ -1568,7 +1446,7 @@ record_full_registers_change (struct regcache
>>>> *regcache, int regnum)
>>>> {
>>>> if (record_full_arch_list_add_reg (regcache, i))
>>>> {
>>>> - record_full_list_release (record_full_arch_list_tail);
>>>> + record_full_reset_incomplete ();
>>>> error (_("Process record: failed to record execution log."));
>>>> }
>>>> }
>>>> @@ -1577,18 +1455,11 @@ record_full_registers_change (struct
>> regcache
>>>> *regcache, int regnum)
>>>> {
>>>> if (record_full_arch_list_add_reg (regcache, regnum))
>>>> {
>>>> - record_full_list_release (record_full_arch_list_tail);
>>>> + record_full_reset_incomplete ();
>>>> error (_("Process record: failed to record execution log."));
>>>> }
>>>> }
>>>> - if (record_full_arch_list_add_end ())
>>>> - {
>>>> - record_full_list_release (record_full_arch_list_tail);
>>>> - error (_("Process record: failed to record execution log."));
>>>> - }
>>>> - record_full_list->next = record_full_arch_list_head;
>>>> - record_full_arch_list_head->prev = record_full_list;
>>>> - record_full_list = record_full_arch_list_tail;
>>>> + record_full_save_instruction ();
>>>>
>>>> if (record_full_insn_num == record_full_insn_max_num)
>>>> record_full_list_release_first ();
>>>> @@ -1607,7 +1478,7 @@ record_full_target::store_registers (struct
>>>> regcache *regcache, int regno)
>>>> {
>>>> int n;
>>>>
>>>> - /* Let user choose if he wants to write register or not. */
>>>> + /* Let user choose if they want to write register or not. */
>>>> if (regno < 0)
>>>> n =
>>>> query (_("Because GDB is in replay mode, changing the "
>>>> @@ -1642,7 +1513,7 @@ record_full_target::store_registers (struct
>>>> regcache *regcache, int regno)
>>>> }
>>>>
>>>> /* Destroy the record from here forward. */
>>>> - record_full_list_release_following (record_full_list);
>>>> + record_full_list_release_following (record_full_next_insn);
>>>> }
>>>>
>>>> record_full_registers_change (regcache, regno);
>>>> @@ -1675,36 +1546,24 @@ record_full_target::xfer_partial (enum
>>>> target_object object,
>>>> error (_("Process record canceled the operation."));
>>>>
>>>> /* Destroy the record from here forward. */
>>>> - record_full_list_release_following (record_full_list);
>>>> + record_full_list_release_following (record_full_next_insn);
>>>> }
>>>>
>>>> /* Check record_full_insn_num */
>>>> record_full_check_insn_num ();
>>>>
>>>> /* Record registers change to list as an instruction. */
>>>> - record_full_arch_list_head = NULL;
>>>> - record_full_arch_list_tail = NULL;
>>>> + record_full_reset_incomplete ();
>>>> if (record_full_arch_list_add_mem (offset, len))
>>>> {
>>>> - record_full_list_release (record_full_arch_list_tail);
>>>> + record_full_reset_incomplete ();
>>>> if (record_debug)
>>>> gdb_printf (gdb_stdlog,
>>>> "Process record: failed to record "
>>>> "execution log.");
>>>> return TARGET_XFER_E_IO;
>>>> }
>>>> - if (record_full_arch_list_add_end ())
>>>> - {
>>>> - record_full_list_release (record_full_arch_list_tail);
>>>> - if (record_debug)
>>>> - gdb_printf (gdb_stdlog,
>>>> - "Process record: failed to record "
>>>> - "execution log.");
>>>> - return TARGET_XFER_E_IO;
>>>> - }
>>>> - record_full_list->next = record_full_arch_list_head;
>>>> - record_full_arch_list_head->prev = record_full_list;
>>>> - record_full_list = record_full_arch_list_tail;
>>>> + record_full_save_instruction ();
>>>>
>>>> if (record_full_insn_num == record_full_insn_max_num)
>>>> record_full_list_release_first ();
>>>> @@ -1866,8 +1725,7 @@ record_full_base_target::get_bookmark (const
>> char
>>>> *args, int from_tty)
>>>> char *ret = NULL;
>>>>
>>>> /* Return stringified form of instruction count. */
>>>> - if (record_full_list && record_full_list->type == record_full_end)
>>>> - ret = xstrdup (pulongest (record_full_list->u.end.insn_num));
>>>> + ret = xstrdup (pulongest
>> (record_full_list[record_full_next_insn].insn_num));
>>> I think we can get here with an empty record_full_list - in case we are in
>> recording mode,
>>> no instructions have been logged and this function is called:
>>>
>>> ~~~
>>> (gdb) info record
>>> Active record target: record-full
>>> Record mode:
>>> No instructions have been logged.
>>> Max logged instructions is 200000.
>>> (gdb) bookmark
>>>
>>> Thread 1 "gdb-up" hit Breakpoint 1, record_full_base_target::get_bookmark
>> (this=0x555558392900 <record_full_ops>, args=0x0, from_tty=1) at
>> /tmp/record-full.c:1774
>>> 1774 char *ret = NULL;
>>> (gdb) p record_full_next_insn
>>> $1 = 0
>>> (gdb) p record_full_list.empty ()
>>> $2 = true
>>> ~~~
> I wonder, do we somewhere have a test for bookmarks?
> I also find a specific description for this in the manual... what's the difference to checkpoints?
Checkpoints fork the inferior and stop the fork immediately, allowing
you to go back to that one point in time, but not executing backwards or
anything, just changing forks and letting you see what things were like
back then (that's why they won't work with multi-threaded programs).
entirely unrelated to reverse debugging
Bookmarks let you mark one instruction in the history and easily go back
to it using the reverse mechanism... at least that's what I've been able
to get from the code, this predates me and I have no idea how it is
actually used....
I quickly grep'd for bookmark tests and couldn't find any. We should
probably add them at some point, if anyone even uses that feature......
>
> I am a bit confused about the bookmark feature (of course, this is nothing to fix for this series...).
>
>>>> if (record_debug)
>>>> {
>>>> @@ -1923,30 +1781,22 @@ record_full_base_target::record_method
>> (ptid_t
>>>> ptid)
>>>> void
>>>> record_full_base_target::info_record ()
>>>> {
>>>> - struct record_full_entry *p;
>>>> -
>>>> if (RECORD_FULL_IS_REPLAY)
>>>> gdb_printf (_("Replay mode:\n"));
>>>> else
>>>> gdb_printf (_("Record mode:\n"));
>>>>
>>>> - /* Find entry for first actual instruction in the log. */
>>>> - for (p = record_full_first.next;
>>>> - p != NULL && p->type != record_full_end;
>>>> - p = p->next)
>>>> - ;
>>>> -
>>>> /* Do we have a log at all? */
>>>> - if (p != NULL && p->type == record_full_end)
>>>> + if (!record_full_list.empty ())
>>>> {
>>>> /* Display instruction number for first instruction in the log. */
>>>> - gdb_printf (_("Lowest recorded instruction number is %s.\n"),
>>>> - pulongest (p->u.end.insn_num));
>>>> + gdb_printf (_("Lowest recorded instruction number is %u.\n"),
>>>> + record_full_list[0].insn_num);
>>>>
>>>> /* If in replay mode, display where we are in the log. */
>>>> if (RECORD_FULL_IS_REPLAY)
>>>> - gdb_printf (_("Current instruction number is %s.\n"),
>>>> - pulongest (record_full_list->u.end.insn_num));
>>>> + gdb_printf (_("Current instruction number is %u.\n"),
>>>> + record_full_list[record_full_next_insn].insn_num);
>>>>
>>>> /* Display instruction number for last instruction in the log. */
>>>> gdb_printf (_("Highest recorded instruction number is %s.\n"),
>>>> @@ -1975,7 +1825,7 @@
>> record_full_base_target::supports_delete_record ()
>>>> void
>>>> record_full_base_target::delete_record ()
>>>> {
>>>> - record_full_list_release_following (record_full_list);
>>>> + record_full_reset_history ();
>>>> }
>>>>
>>>> /* The "record_is_replaying" target method. */
>>>> @@ -2001,23 +1851,23 @@ record_full_base_target::record_will_replay
>>>> (ptid_t ptid, int dir)
>>>> /* Go to a specific entry. */
>>>>
>>>> static void
>>>> -record_full_goto_entry (struct record_full_entry *p)
>>>> +record_full_goto_entry (size_t target_insn)
>>>> {
>>>> - if (p == NULL)
>>>> + if (target_insn >= record_full_list.size ())
>>>> error (_("Target insn not found."));
>>>> - else if (p == record_full_list)
>>>> + else if (target_insn == record_full_next_insn)
>>>> error (_("Already at target insn."));
>>>> - else if (p->u.end.insn_num > record_full_list->u.end.insn_num)
>>>> + else if (target_insn > record_full_next_insn)
>>>> {
>>>> gdb_printf (_("Go forward to insn number %s\n"),
>>>> - pulongest (p->u.end.insn_num));
>>>> - record_full_goto_insn (p, EXEC_FORWARD);
>>>> + pulongest (record_full_list[target_insn].insn_num));
>>>> + record_full_goto_insn (target_insn, EXEC_FORWARD);
>>>> }
>>>> else
>>>> {
>>>> gdb_printf (_("Go backward to insn number %s\n"),
>>>> - pulongest (p->u.end.insn_num));
>>>> - record_full_goto_insn (p, EXEC_REVERSE);
>>>> + pulongest (target_insn));
>>>> + record_full_goto_insn (target_insn, EXEC_REVERSE);
>>>> }
>>>>
>>>> registers_changed ();
>>>> @@ -2033,13 +1883,7 @@ record_full_goto_entry (struct
>> record_full_entry
>>>> *p)
>>>> void
>>>> record_full_base_target::goto_record_begin ()
>>>> {
>>>> - struct record_full_entry *p = NULL;
>>>> -
>>>> - for (p = &record_full_first; p != NULL; p = p->next)
>>>> - if (p->type == record_full_end)
>>>> - break;
>>>> -
>>>> - record_full_goto_entry (p);
>>>> + record_full_goto_entry (0);
>>>> }
>>>>
>>>> /* The "goto_record_end" target method. */
>>>> @@ -2047,15 +1891,7 @@ record_full_base_target::goto_record_begin ()
>>>> void
>>>> record_full_base_target::goto_record_end ()
>>>> {
>>>> - struct record_full_entry *p = NULL;
>>>> -
>>>> - for (p = record_full_list; p->next != NULL; p = p->next)
>>>> - ;
>>>> - for (; p!= NULL; p = p->prev)
>>>> - if (p->type == record_full_end)
>>>> - break;
>>>> -
>>>> - record_full_goto_entry (p);
>>>> + record_full_goto_entry (record_full_list.size () -1);
>>> Nit: whitespace before 1 => "record_full_list.size () - 1"
>>>
>>> And in case the record_full_list is empty, won't we call
>>> record_full_goto_entry with an invalid value for target_insn ?
>>>
>>>> }
>>>>
>>>> /* The "goto_record" target method. */
>>>> @@ -2063,13 +1899,7 @@ record_full_base_target::goto_record_end ()
>>>> void
>>>> record_full_base_target::goto_record (ULONGEST target_insn)
>>>> {
>>>> - struct record_full_entry *p = NULL;
>>>> -
>>>> - for (p = &record_full_first; p != NULL; p = p->next)
>>>> - if (p->type == record_full_end && p->u.end.insn_num == target_insn)
>>>> - break;
>>>> -
>>>> - record_full_goto_entry (p);
>>>> + record_full_goto_entry (target_insn);
>>>> }
>>>>
>>>> /* The "record_stop_replaying" target method. */
>>>> @@ -2339,19 +2169,96 @@ netorder32 (uint32_t input)
>>>> return ret;
>>>> }
>>>>
>>>> +static void
>>>> +record_full_read_entry_from_bfd (bfd *cbfd, asection *osec, int
>> *bfd_offset)
>>>> +{
>>>> + uint8_t rectype;
>>>> + uint32_t regnum, len;
>>>> + uint64_t addr;
>>>> + regcache *cache = get_thread_regcache (inferior_thread ());
>>>> +
>>>> + bfdcore_read (cbfd, osec, &rectype, sizeof (rectype), bfd_offset);
>>>> + switch (rectype)
>>>> + {
>>>> + case record_full_reg: /* reg */
>>>> + {
>>>> + /* Get register number to regnum. */
>>>> + bfdcore_read (cbfd, osec, ®num, sizeof (regnum), bfd_offset);
>>>> + regnum = netorder32 (regnum);
>>>> +
>>>> + record_full_entry rec;
>>>> +
>>>> + rec = record_full_reg_init (cache, regnum);
>>>> +
>>>> + /* Get val. */
>>>> + bfdcore_read (cbfd, osec, record_full_get_loc (&rec),
>>>> + rec.u.reg.len, bfd_offset);
>>>> +
>>>> + if (record_debug)
>>>> + gdb_printf (gdb_stdlog,
>>>> + " Reading register %d (1 "
>>>> + "plus %lu plus %d bytes)\n",
>>>> + rec.u.reg.num,
>>>> + (unsigned long) sizeof (regnum),
>>>> + rec.u.reg.len);
>>>> +
>>>> + record_full_arch_list_add (rec);
>>>> + break;
>>>> + }
>>>> +
>>>> + case record_full_mem: /* mem */
>>>> + {
>>>> + /* Get len. */
>>>> + bfdcore_read (cbfd, osec, &len, sizeof (len), bfd_offset);
>>>> + len = netorder32 (len);
>>>> +
>>>> + /* Get addr. */
>>>> + bfdcore_read (cbfd, osec, &addr, sizeof (addr),
>>>> + bfd_offset);
>>>> + addr = netorder64 (addr);
>>>> +
>>>> + record_full_entry rec;
>>>> + rec = record_full_mem_init (addr, len);
>>>> +
>>>> + /* Get val. */
>>>> + bfdcore_read (cbfd, osec, record_full_get_loc (&rec), len,
>>>> + bfd_offset);
>>>> +
>>>> + if (record_debug)
>>>> + gdb_printf (gdb_stdlog,
>>>> + " Reading memory %s (1 plus "
>>>> + "%lu plus %lu plus %d bytes)\n",
>>>> + paddress (get_current_arch (),
>>>> + rec.u.mem.addr),
>>>> + (unsigned long) sizeof (addr),
>>>> + (unsigned long) sizeof (len),
>>>> + len);
>>>> +
>>>> + record_full_arch_list_add (rec);
>>>> + break;
>>>> + }
>>>> +
>>>> + default:
>>>> + error (_("Bad entry type %d, offset %d of %lu in core file %ps."),
>>>> + rectype, *bfd_offset, bfd_section_size (osec),
>>>> + styled_string (file_name_style.style (),
>>>> + bfd_get_filename (cbfd)));
>>>> + break;
>>>> + }
>>>> +}
>>>> +
>>>> /* Restore the execution log from core file CBFD. */
>>>>
>>>> static void
>>>> record_full_restore (struct bfd &cbfd)
>>>> {
>>>> uint32_t magic;
>>>> - struct record_full_entry *rec;
>>>> asection *osec;
>>>> uint32_t osec_size;
>>>> int bfd_offset = 0;
>>>>
>>>> /* "record_full_restore" can only be called when record list is empty. */
>>>> - gdb_assert (record_full_first.next == NULL);
>>>> + gdb_assert (record_full_list.empty ());
>>>>
>>>> if (record_debug)
>>>> gdb_printf (gdb_stdlog, "Restoring recording from core file.\n");
>>>> @@ -2379,124 +2286,47 @@ record_full_restore (struct bfd &cbfd)
>>>> "RECORD_FULL_FILE_MAGIC (0x%s)\n",
>>>> phex_nz (netorder32 (magic), 4));
>>>>
>>>> - /* Restore the entries in recfd into record_full_arch_list_head and
>>>> - record_full_arch_list_tail. */
>>>> - record_full_arch_list_head = NULL;
>>>> - record_full_arch_list_tail = NULL;
>>>> record_full_insn_num = 0;
>>>>
>>>> try
>>>> {
>>>> - regcache *regcache = get_thread_regcache (inferior_thread ());
>>>> -
>>>> - while (1)
>>>> + while (bfd_offset < osec_size)
>>>> {
>>>> - uint8_t rectype;
>>>> - uint32_t regnum, len, signal, count;
>>>> - uint64_t addr;
>>>> -
>>>> - /* We are finished when offset reaches osec_size. */
>>>> - if (bfd_offset >= osec_size)
>>>> - break;
>>>> - bfdcore_read (&cbfd, osec, &rectype, sizeof (rectype), &bfd_offset);
>>>> -
>>>> - switch (rectype)
>>>> + record_full_reset_incomplete ();
>>>> + uint32_t eff_count = 0;
>>>> + uint8_t sigval;
>>>> + uint32_t insn_num;
>>>> +
>>>> + /* First read the generic information for an instruction. */
>>>> + bfdcore_read (&cbfd, osec, &sigval, sizeof (uint8_t), &bfd_offset);
>>>> + bfdcore_read (&cbfd, osec, &eff_count, sizeof (uint32_t),
>>>> + &bfd_offset);
>>>> + bfdcore_read (&cbfd, osec, &insn_num, sizeof (uint32_t),
>>>> + &bfd_offset);
>>>> +
>>>> + record_full_incomplete_instruction.insn_num = netorder32
>>>> (insn_num);
>>>> + if (sigval != GDB_SIGNAL_0)
>>>> + record_full_incomplete_instruction.sigval = (gdb_signal) sigval;
>>>> +
>>>> + eff_count = netorder32 (eff_count);
>>>> +
>>>> + /* This deals with all the side effects. */
>>>> + while (eff_count > 0)
>>>> {
>>> There is one space too much indent.
>>>
>>>> - case record_full_reg: /* reg */
>>>> - /* Get register number to regnum. */
>>>> - bfdcore_read (&cbfd, osec, ®num, sizeof (regnum),
>>>> - &bfd_offset);
>>>> - regnum = netorder32 (regnum);
>>>> -
>>>> - rec = record_full_reg_alloc (regcache, regnum);
>>>> -
>>>> - /* Get val. */
>>>> - bfdcore_read (&cbfd, osec, record_full_get_loc (rec),
>>>> - rec->u.reg.len, &bfd_offset);
>>>> -
>>>> - if (record_debug)
>>>> - gdb_printf (gdb_stdlog,
>>>> - " Reading register %d (1 "
>>>> - "plus %lu plus %d bytes)\n",
>>>> - rec->u.reg.num,
>>>> - (unsigned long) sizeof (regnum),
>>>> - rec->u.reg.len);
>>>> - break;
>>>> + eff_count--;
>>>>
>>>> - case record_full_mem: /* mem */
>>>> - /* Get len. */
>>>> - bfdcore_read (&cbfd, osec, &len, sizeof (len), &bfd_offset);
>>>> - len = netorder32 (len);
>>>> -
>>>> - /* Get addr. */
>>>> - bfdcore_read (&cbfd, osec, &addr, sizeof (addr), &bfd_offset);
>>>> - addr = netorder64 (addr);
>>>> -
>>>> - rec = record_full_mem_alloc (addr, len);
>>>> -
>>>> - /* Get val. */
>>>> - bfdcore_read (&cbfd, osec, record_full_get_loc (rec),
>>>> - rec->u.mem.len, &bfd_offset);
>>>> -
>>>> - if (record_debug)
>>>> - gdb_printf (gdb_stdlog,
>>>> - " Reading memory %s (1 plus "
>>>> - "%lu plus %lu plus %d bytes)\n",
>>>> - paddress (get_current_arch (),
>>>> - rec->u.mem.addr),
>>>> - (unsigned long) sizeof (addr),
>>>> - (unsigned long) sizeof (len),
>>>> - rec->u.mem.len);
>>>> - break;
>>>> -
>>>> - case record_full_end: /* end */
>>>> - rec = record_full_end_alloc ();
>>>> - record_full_insn_num ++;
>>>> -
>>>> - /* Get signal value. */
>>>> - bfdcore_read (&cbfd, osec, &signal, sizeof (signal),
>>>> - &bfd_offset);
>>>> - signal = netorder32 (signal);
>>>> - rec->u.end.sigval = (enum gdb_signal) signal;
>>>> -
>>>> - /* Get insn count. */
>>>> - bfdcore_read (&cbfd, osec, &count, sizeof (count), &bfd_offset);
>>>> - count = netorder32 (count);
>>>> - rec->u.end.insn_num = count;
>>>> - record_full_insn_count = count + 1;
>>>> - if (record_debug)
>>>> - gdb_printf (gdb_stdlog,
>>>> - " Reading record_full_end (1 + "
>>>> - "%lu + %lu bytes), offset == %s\n",
>>>> - (unsigned long) sizeof (signal),
>>>> - (unsigned long) sizeof (count),
>>>> - paddress (get_current_arch (),
>>>> - bfd_offset));
>>>> - break;
>>>> -
>>>> - default:
>>>> - error (_("Bad entry type in core file %ps."),
>>>> - styled_string (file_name_style.style (),
>>>> - bfd_get_filename (&cbfd)));
>>>> - break;
>>>> + record_full_read_entry_from_bfd (&cbfd, osec, &bfd_offset);
>>>> }
>>>>
>>>> - /* Add rec to record arch list. */
>>>> - record_full_arch_list_add (rec);
>>>> + record_full_save_instruction ();
>>>> }
>>>> }
>>>> catch (const gdb_exception &ex)
>>>> {
>>>> - record_full_list_release (record_full_arch_list_tail);
>>>> + record_full_reset_incomplete ();
>>>> throw;
>>>> }
>>>>
>>>> - /* Add record_full_arch_list_head to the end of record list. */
>>>> - record_full_first.next = record_full_arch_list_head;
>>>> - record_full_arch_list_head->prev = &record_full_first;
>>>> - record_full_arch_list_tail->next = NULL;
>>>> - record_full_list = &record_full_first;
>>>> -
>>>> /* Update record_full_insn_max_num. */
>>>> if (record_full_insn_num > record_full_insn_max_num)
>>>> {
>>>> @@ -2505,6 +2335,10 @@ record_full_restore (struct bfd &cbfd)
>>>> record_full_insn_max_num);
>>>> }
>>>>
>>>> + /* When loading a recording, we'll always start at the oldest possible
>>>> + instruction, no matter where the original recording was stopped. */
>>>> + record_full_next_insn = 0;
>>>> +
>>>> /* Succeeded. */
>>>> gdb_printf (_("Restored records from core file %s.\n"),
>>>> bfd_get_filename (&cbfd));
>>>> @@ -2538,13 +2372,73 @@ cmd_record_full_restore (const char *args,
>> int
>>>> from_tty)
>>>> record_full_open (nullptr, from_tty);
>>>> }
>>>>
>>>> +static void
>>>> +record_full_write_entry_to_bfd (record_full_entry &entry,
>>>> + gdb_bfd_ref_ptr obfd,
>>>> + asection *osec, int *bfd_offset,
>>>> + struct gdbarch *gdbarch)
>>>> +{
>>>> + /* Save entry. */
>>>> + uint8_t type;
>>>> + uint32_t regnum, len;
>>>> + uint64_t addr;
>>>> +
>>>> + type = entry.type;
>>>> + bfdcore_write (obfd.get (), osec, &type, sizeof (type), bfd_offset);
>>>> +
>>>> + switch (entry.type)
>>>> + {
>>>> + case record_full_reg: /* reg */
>>>> + if (record_debug)
>>>> + gdb_printf (gdb_stdlog,
>>>> + " Writing register %d (1 "
>>>> + "plus %lu plus %d bytes)\n",
>>>> + entry.u.reg.num,
>>>> + (unsigned long) sizeof (regnum),
>>>> + entry.u.reg.len);
>>>> +
>>>> + /* Write regnum. */
>>>> + regnum = netorder32 (entry.u.reg.num);
>>>> + bfdcore_write (obfd.get (), osec, ®num, sizeof (regnum),
>> bfd_offset);
>>>> +
>>>> + /* Write regval. */
>>>> + bfdcore_write (obfd.get (), osec, record_full_get_loc (&entry),
>>>> + entry.u.reg.len, bfd_offset);
>>>> + break;
>>>> +
>>>> + case record_full_mem: /* mem */
>>>> + if (record_debug)
>>>> + gdb_printf (gdb_stdlog,
>>>> + " Writing memory %s (1 plus "
>>>> + "%lu plus %lu plus %d bytes)\n",
>>>> + paddress (gdbarch,
>>>> + entry.u.mem.addr),
>>>> + (unsigned long) sizeof (addr),
>>>> + (unsigned long) sizeof (len),
>>>> + entry.u.mem.len);
>>>> +
>>>> + /* Write memlen. */
>>>> + len = netorder32 (entry.u.mem.len);
>>>> + bfdcore_write (obfd.get (), osec, &len, sizeof (len), bfd_offset);
>>>> +
>>>> + /* Write memaddr. */
>>>> + addr = netorder64 (entry.u.mem.addr);
>>>> + bfdcore_write (obfd.get (), osec, &addr, sizeof (addr), bfd_offset);
>>>> +
>>>> + /* Write memval. */
>>>> + bfdcore_write (obfd.get (), osec, record_full_get_loc (&entry),
>>>> + entry.u.mem.len, bfd_offset);
>>>> + break;
>>>> + }
>>>> +
>>>> +}
>>>> +
>>>> /* Save the execution log to a file. We use a modified elf corefile
>>>> format, with an extra section for our data. */
>>>>
>>>> void
>>>> record_full_base_target::save_record (const char *recfilename)
>>>> {
>>>> - struct record_full_entry *cur_record_full_list;
>>>> uint32_t magic;
>>>> struct gdbarch *gdbarch;
>>>> int save_size = 0;
>>>> @@ -2562,9 +2456,6 @@ record_full_base_target::save_record (const
>> char
>>>> *recfilename)
>>>> /* Arrange to remove the output file on failure. */
>>>> gdb::unlinker unlink_file (recfilename);
>>>>
>>>> - /* Save the current record entry to "cur_record_full_list". */
>>>> - cur_record_full_list = record_full_list;
>>>> -
>>>> /* Get the values of regcache and gdbarch. */
>>>> regcache *regcache = get_thread_regcache (inferior_thread ());
>>>> gdbarch = regcache->arch ();
>>>> @@ -2574,34 +2465,27 @@ record_full_base_target::save_record (const
>>>> char *recfilename)
>>>> = record_full_gdb_operation_disable_set ();
>>>>
>>>> /* Reverse execute to the begin of record list. */
>>>> - while (1)
>>>> - {
>>>> - /* Check for beginning and end of log. */
>>>> - if (record_full_list == &record_full_first)
>>>> - break;
>>>> -
>>>> - record_full_exec_insn (regcache, gdbarch, record_full_list);
>>>> -
>>>> - if (record_full_list->prev)
>>>> - record_full_list = record_full_list->prev;
>>>> - }
>>>> + for (int i = record_full_next_insn - 1; i >= 0; i--)
>>>> + record_full_exec_insn (regcache, gdbarch,
>>>> + record_full_list[i]);
>>>>
>>>> /* Compute the size needed for the extra bfd section. */
>>>> save_size = 4; /* magic cookie */
>>>> - for (record_full_list = record_full_first.next; record_full_list;
>>>> - record_full_list = record_full_list->next)
>>>> - switch (record_full_list->type)
>>>> - {
>>>> - case record_full_end:
>>>> - save_size += 1 + 4 + 4;
>>>> - break;
>>>> - case record_full_reg:
>>>> - save_size += 1 + 4 + record_full_list->u.reg.len;
>>>> - break;
>>>> - case record_full_mem:
>>>> - save_size += 1 + 4 + 8 + record_full_list->u.mem.len;
>>>> - break;
>>>> - }
>>>> + for (int i = record_full_list.size () - 1; i >= 0; i--)
>>>> + {
>>>> + /* Number of effects of an instruction. */
>>>> + save_size += sizeof (uint32_t) + sizeof (uint8_t) + sizeof (uint32_t);
>>>> + for (auto &entry : record_full_list[i].effects)
>>>> + switch (entry.type)
>>>> + {
>>>> + case record_full_reg:
>>>> + save_size += 1 + 4 + entry.u.reg.len;
>>>> + break;
>>>> + case record_full_mem:
>>>> + save_size += 1 + 4 + 8 + entry.u.mem.len;
>>>> + break;
>>>> + }
>>>> + }
>>>>
>>>> /* Make the new bfd section. */
>>>> osec = bfd_make_section_anyway_with_flags (obfd.get (), "precord",
>>>> @@ -2630,108 +2514,32 @@ record_full_base_target::save_record
>> (const
>>>> char *recfilename)
>>>>
>>>> /* Save the entries to recfd and forward execute to the end of
>>>> record list. */
>>>> - record_full_list = &record_full_first;
>>>> - while (1)
>>>> + for (int i = 0; i < record_full_list.size (); i++)
>>>> {
>>>> - /* Save entry. */
>>>> - if (record_full_list != &record_full_first)
>>>> + uint32_t eff_count = (uint32_t) record_full_list[i].effects.size ();
>>>> + uint32_t insn_num = record_full_list[i].insn_num;
>>>> + uint8_t sigval = (record_full_list[i].sigval.has_value ())
>>>> + ? record_full_list[i].sigval.value ()
>>>> + : GDB_SIGNAL_0;
>>>> +
>>>> + /* Signal. */
>>>> + bfdcore_write (obfd.get (), osec, &sigval, sizeof (sigval), &bfd_offset);
>>>> + eff_count = netorder32 (eff_count);
>>>> + /* Number of effects. */
>>>> + bfdcore_write (obfd.get (), osec, &eff_count, sizeof (eff_count),
>>>> + &bfd_offset);
>>>> + /* Instruction number. */
>>>> + bfdcore_write (obfd.get (), osec, &insn_num, sizeof (uint32_t),
>>>> + &bfd_offset);
>>>> +
>>>> + for (auto &entry : record_full_list[i].effects)
>>>> {
>>>> - uint8_t type;
>>>> - uint32_t regnum, len, signal, count;
>>>> - uint64_t addr;
>>>> -
>>>> - type = record_full_list->type;
>>>> - bfdcore_write (obfd.get (), osec, &type, sizeof (type), &bfd_offset);
>>>> -
>>>> - switch (record_full_list->type)
>>>> - {
>>>> - case record_full_reg: /* reg */
>>>> - if (record_debug)
>>>> - gdb_printf (gdb_stdlog,
>>>> - " Writing register %d (1 "
>>>> - "plus %lu plus %d bytes)\n",
>>>> - record_full_list->u.reg.num,
>>>> - (unsigned long) sizeof (regnum),
>>>> - record_full_list->u.reg.len);
>>>> -
>>>> - /* Write regnum. */
>>>> - regnum = netorder32 (record_full_list->u.reg.num);
>>>> - bfdcore_write (obfd.get (), osec, ®num,
>>>> - sizeof (regnum), &bfd_offset);
>>>> -
>>>> - /* Write regval. */
>>>> - bfdcore_write (obfd.get (), osec,
>>>> - record_full_get_loc (record_full_list),
>>>> - record_full_list->u.reg.len, &bfd_offset);
>>>> - break;
>>>> -
>>>> - case record_full_mem: /* mem */
>>>> - if (record_debug)
>>>> - gdb_printf (gdb_stdlog,
>>>> - " Writing memory %s (1 plus "
>>>> - "%lu plus %lu plus %d bytes)\n",
>>>> - paddress (gdbarch,
>>>> - record_full_list->u.mem.addr),
>>>> - (unsigned long) sizeof (addr),
>>>> - (unsigned long) sizeof (len),
>>>> - record_full_list->u.mem.len);
>>>> -
>>>> - /* Write memlen. */
>>>> - len = netorder32 (record_full_list->u.mem.len);
>>>> - bfdcore_write (obfd.get (), osec, &len, sizeof (len),
>>>> - &bfd_offset);
>>>> -
>>>> - /* Write memaddr. */
>>>> - addr = netorder64 (record_full_list->u.mem.addr);
>>>> - bfdcore_write (obfd.get (), osec, &addr,
>>>> - sizeof (addr), &bfd_offset);
>>>> -
>>>> - /* Write memval. */
>>>> - bfdcore_write (obfd.get (), osec,
>>>> - record_full_get_loc (record_full_list),
>>>> - record_full_list->u.mem.len, &bfd_offset);
>>>> - break;
>>>> -
>>>> - case record_full_end:
>>>> - if (record_debug)
>>>> - gdb_printf (gdb_stdlog,
>>>> - " Writing record_full_end (1 + "
>>>> - "%lu + %lu bytes)\n",
>>>> - (unsigned long) sizeof (signal),
>>>> - (unsigned long) sizeof (count));
>>>> - /* Write signal value. */
>>>> - signal = netorder32 (record_full_list->u.end.sigval);
>>>> - bfdcore_write (obfd.get (), osec, &signal,
>>>> - sizeof (signal), &bfd_offset);
>>>> -
>>>> - /* Write insn count. */
>>>> - count = netorder32 (record_full_list->u.end.insn_num);
>>>> - bfdcore_write (obfd.get (), osec, &count,
>>>> - sizeof (count), &bfd_offset);
>>>> - break;
>>>> - }
>>>> + record_full_write_entry_to_bfd (entry, obfd, osec, &bfd_offset,
>>>> + gdbarch);
>>>> }
>>>> -
>>>> /* Execute entry. */
>>>> - record_full_exec_insn (regcache, gdbarch, record_full_list);
>>>> -
>>>> - if (record_full_list->next)
>>>> - record_full_list = record_full_list->next;
>>>> - else
>>>> - break;
>>>> - }
>>>> -
>>>> - /* Reverse execute to cur_record_full_list. */
>>>> - while (1)
>>>> - {
>>>> - /* Check for beginning and end of log. */
>>>> - if (record_full_list == cur_record_full_list)
>>>> - break;
>>>> -
>>>> - record_full_exec_insn (regcache, gdbarch, record_full_list);
>>>> -
>>>> - if (record_full_list->prev)
>>>> - record_full_list = record_full_list->prev;
>>>> + if (i < record_full_next_insn)
>>>> + record_full_exec_insn (regcache, gdbarch, record_full_list[i]);
>>>> }
>>>>
>>>> unlink_file.keep ();
>>>> @@ -2746,7 +2554,7 @@ record_full_base_target::save_record (const
>> char
>>>> *recfilename)
>>>> correspondingly. */
>>>>
>>>> static void
>>>> -record_full_goto_insn (struct record_full_entry *entry,
>>>> +record_full_goto_insn (size_t target_insn,
>>>> enum exec_direction_kind dir)
>>> You could explain the new parameter in the function description.
>>>
>>>> {
>>>> scoped_restore restore_operation_disable
>>>> @@ -2757,17 +2565,12 @@ record_full_goto_insn (struct
>> record_full_entry
>>>> *entry,
>>>> /* Assume everything is valid: we will hit the entry,
>>>> and we will not hit the end of the recording. */
>>>>
>>>> - if (dir == EXEC_FORWARD)
>>>> - record_full_list = record_full_list->next;
>>>> -
>>>> - do
>>>> - {
>>>> - record_full_exec_insn (regcache, gdbarch, record_full_list);
>>>> - if (dir == EXEC_REVERSE)
>>>> - record_full_list = record_full_list->prev;
>>>> - else
>>>> - record_full_list = record_full_list->next;
>>>> - } while (record_full_list != entry);
>>>> + if (dir == EXEC_REVERSE)
>>>> + for (int i = record_full_next_insn; i > target_insn; i--)
>>>> + record_full_exec_insn (regcache, gdbarch, record_full_list[i - 1]);
>>>> + else
>>>> + for (int i = record_full_next_insn; i < target_insn; i++)
>>>> + record_full_exec_insn (regcache, gdbarch, record_full_list[i]);
>>>> }
>>>>
>>>> /* Alias for "target record-full". */
>>>> @@ -2798,61 +2601,36 @@ set_record_full_insn_max_num (const char
>>>> *args, int from_tty,
>>>> static void
>>>> maintenance_print_record_instruction (const char *args, int from_tty)
>>>> {
>>>> - struct record_full_entry *to_print = record_full_list;
>>>> + if (record_full_list.empty ())
>>>> + error (_("Not enough recorded history"));
>>>>
>>>> + int offset = record_full_next_insn - 1;
>>>> + /* Reduce the offset by 1 if the record_full_next_insn is after the end
>>>> + so that we show the last recorded instruction instead of crashing. */
>>>> + if (offset == record_full_list.size ())
>>>> + offset--;
>>>> if (args != nullptr)
>>>> {
>>>> - int offset = value_as_long (parse_and_eval (args));
>>>> - if (offset > 0)
>>>> - {
>>>> - /* Move forward OFFSET instructions. We know we found the
>>>> - end of an instruction when to_print->type is record_full_end. */
>>>> - while (to_print->next != nullptr && offset > 0)
>>>> - {
>>>> - to_print = to_print->next;
>>>> - if (to_print->type == record_full_end)
>>>> - offset--;
>>>> - }
>>>> - if (offset != 0)
>>>> - error (_("Not enough recorded history"));
>>>> - }
>>>> - else
>>>> - {
>>>> - while (to_print->prev != nullptr && offset < 0)
>>>> - {
>>>> - to_print = to_print->prev;
>>>> - if (to_print->type == record_full_end)
>>>> - offset++;
>>>> - }
>>>> - if (offset != 0)
>>>> - error (_("Not enough recorded history"));
>>>> - }
>>>> + offset += value_as_long (parse_and_eval (args));
>>>> + if (offset >= record_full_list.size () || offset < 0)
>>>> + error (_("Not enough recorded history"));
>>>> }
>>>> - gdb_assert (to_print != nullptr);
>>>> + auto to_print = record_full_list.begin () + offset;
>>>>
>>>> gdbarch *arch = current_inferior ()->arch ();
>>>>
>>>> - /* Go back to the start of the instruction. */
>>>> - while (to_print->prev != nullptr && to_print->prev->type !=
>> record_full_end)
>>>> - to_print = to_print->prev;
>>>> -
>>>> - /* if we're in the first record, there are no actual instructions
>>>> - recorded. Warn the user and leave. */
>>>> - if (to_print == &record_full_first)
>>>> - error (_("Not enough recorded history"));
>>>> -
>>>> - while (to_print->type != record_full_end)
>>>> + for (auto entry : to_print->effects)
>>>> {
>>>> - switch (to_print->type)
>>>> + switch (entry.type)
>>>> {
>>>> case record_full_reg:
>>>> {
>>>> - type *regtype = gdbarch_register_type (arch, to_print-
>>>>> u.reg.num);
>>>> + type *regtype = gdbarch_register_type (arch, entry.u.reg.num);
>>>> value *val
>>>> = value_from_contents (regtype,
>>>> - record_full_get_loc (to_print));
>>>> + record_full_get_loc (&entry));
>>>> gdb_printf ("Register %s changed: ",
>>>> - gdbarch_register_name (arch, to_print-
>>>>> u.reg.num));
>>>> + gdbarch_register_name (arch, entry.u.reg.num));
>>>> struct value_print_options opts;
>>>> get_user_print_options (&opts);
>>>> opts.raw = true;
>>>> @@ -2862,17 +2640,16 @@ maintenance_print_record_instruction
>> (const
>>>> char *args, int from_tty)
>>>> }
>>>> case record_full_mem:
>>>> {
>>>> - gdb_byte *b = record_full_get_loc (to_print);
>>>> + gdb_byte *b = record_full_get_loc (&entry);
>>>> gdb_printf ("%d bytes of memory at address %s changed from:",
>>>> - to_print->u.mem.len,
>>>> - print_core_address (arch, to_print->u.mem.addr));
>>>> - for (int i = 0; i < to_print->u.mem.len; i++)
>>>> + entry.u.mem.len,
>>>> + print_core_address (arch, entry.u.mem.addr));
>>>> + for (int i = 0; i < entry.u.mem.len; i++)
>>>> gdb_printf (" %02x", b[i]);
>>>> gdb_printf ("\n");
>>>> break;
>>>> }
>>>> }
>>>> - to_print = to_print->next;
>>>> }
>>>> }
>>>>
>>>> @@ -2880,11 +2657,6 @@ INIT_GDB_FILE (record_full)
>>>> {
>>>> struct cmd_list_element *c;
>>>>
>>>> - /* Init record_full_first. */
>>>> - record_full_first.prev = NULL;
>>>> - record_full_first.next = NULL;
>>>> - record_full_first.type = record_full_end;
>>>> -
>>>> add_target (record_full_target_info, record_full_open);
>>>> add_deprecated_target_alias (record_full_target_info, "record");
>>>> add_target (record_full_core_target_info, record_full_open);
>>>> diff --git a/gdb/record-full.h b/gdb/record-full.h
>>>> index 51effe74560..c327d879a8a 100644
>>>> --- a/gdb/record-full.h
>>>> +++ b/gdb/record-full.h
>>>> @@ -41,7 +41,6 @@ enum record_result
>>>>
>>>> extern int record_full_arch_list_add_reg (struct regcache *regcache, int
>>>> num);
>>>> extern int record_full_arch_list_add_mem (CORE_ADDR addr, int len);
>>>> -extern int record_full_arch_list_add_end (void);
>>>>
>>>> /* Returns true if the process record target is open. */
>>>> extern int record_full_is_used (void);
>>>> diff --git a/gdb/riscv-tdep.c b/gdb/riscv-tdep.c
>>>> index 6b5c9c02d46..f5b1f66844c 100644
>>>> --- a/gdb/riscv-tdep.c
>>>> +++ b/gdb/riscv-tdep.c
>>>> @@ -5466,8 +5466,5 @@ riscv_process_record (struct gdbarch *gdbarch,
>>>> struct regcache *regcache,
>>>> if (res != RECORD_SUCCESS)
>>>> return res;
>>>>
>>>> - if (record_full_arch_list_add_end ())
>>>> - return -1;
>>>> -
>>>> return 0;
>>>> }
>>>> diff --git a/gdb/rs6000-tdep.c b/gdb/rs6000-tdep.c
>>>> index e135df94a40..f964889a49f 100644
>>>> --- a/gdb/rs6000-tdep.c
>>>> +++ b/gdb/rs6000-tdep.c
>>>> @@ -7138,8 +7138,6 @@ ppc_process_prefix_instruction (int insn_prefix,
>> int
>>>> insn_suffix,
>>>> if (record_full_arch_list_add_reg (regcache, PPC_PC_REGNUM))
>>>> return -1;
>>>>
>>>> - if (record_full_arch_list_add_end ())
>>>> - return -1;
>>>> return 0;
>>>> }
>>>>
>>>> @@ -7447,8 +7445,6 @@ ppc_process_record (struct gdbarch *gdbarch,
>>>> struct regcache *regcache,
>>>>
>>>> if (record_full_arch_list_add_reg (regcache, PPC_PC_REGNUM))
>>>> return -1;
>>>> - if (record_full_arch_list_add_end ())
>>>> - return -1;
>>>> return 0;
>>>> }
>>>>
>>>> diff --git a/gdb/s390-linux-tdep.c b/gdb/s390-linux-tdep.c
>>>> index 3cd6b359d13..6bea30f08dc 100644
>>>> --- a/gdb/s390-linux-tdep.c
>>>> +++ b/gdb/s390-linux-tdep.c
>>>> @@ -910,9 +910,6 @@ s390_linux_record_signal (struct gdbarch
>> *gdbarch,
>>>> struct regcache *regcache,
>>>> if (record_full_arch_list_add_mem (sp, sizeof_rt_sigframe))
>>>> return -1;
>>>>
>>>> - if (record_full_arch_list_add_end ())
>>>> - return -1;
>>>> -
>>>> return 0;
>>>> }
>>>>
>>>> diff --git a/gdb/s390-tdep.c b/gdb/s390-tdep.c
>>>> index f9d7bdd04e4..36ce659ea15 100644
>>>> --- a/gdb/s390-tdep.c
>>>> +++ b/gdb/s390-tdep.c
>>>> @@ -7019,8 +7019,6 @@ s390_process_record (struct gdbarch *gdbarch,
>>>> struct regcache *regcache,
>>>>
>>>> if (record_full_arch_list_add_reg (regcache, S390_PSWA_REGNUM))
>>>> return -1;
>>>> - if (record_full_arch_list_add_end ())
>>>> - return -1;
>>>> return 0;
>>>> }
>>>>
>>>> --
>>>> 2.53.0
>>>>
>>> Kind Regards,
>>> Christina
>>>
>>> Intel Deutschland GmbH
>>> Registered Address: Dornacher Strasse 1, 85622 Feldkirchen, Germany
>>> Tel: +49 89 991 430, www.intel.de
>>> Managing Directors: Harry Demas, Jeffrey Schneiderman, Yin Chong Sorrell
>>> Chairperson of the Supervisory Board: Nicole Lau
>>> Registered Seat: Munich
>>> Commercial Register: Amtsgericht Muenchen HRB 186928
>>>
> Christina
> Intel Deutschland GmbH
> Registered Address: Dornacher Strasse 1, 85622 Feldkirchen, Germany
> Tel: +49 89 991 430, www.intel.de
> Managing Directors: Harry Demas, Jeffrey Schneiderman, Yin Chong Sorrell
> Chairperson of the Supervisory Board: Nicole Lau
> Registered Seat: Munich
> Commercial Register: Amtsgericht Muenchen HRB 186928
>
--
Cheers,
Guinevere Larsen
It/she
^ permalink raw reply [flat|nested] 19+ messages in thread
* RE: [PATCH v2 1/6] gdb/record: Refactor record history
2026-05-12 18:50 ` Guinevere Larsen
@ 2026-05-13 7:54 ` Schimpe, Christina
2026-05-14 15:20 ` Guinevere Larsen
0 siblings, 1 reply; 19+ messages in thread
From: Schimpe, Christina @ 2026-05-13 7:54 UTC (permalink / raw)
To: Guinevere Larsen, gdb-patches
Hi Guinevere,
> -----Original Message-----
> From: Guinevere Larsen <guinevere@redhat.com>
> Sent: Dienstag, 12. Mai 2026 20:51
> To: Schimpe, Christina <christina.schimpe@intel.com>; gdb-
> patches@sourceware.org
> Subject: Re: [PATCH v2 1/6] gdb/record: Refactor record history
>
> On 5/11/26 12:23 PM, Schimpe, Christina wrote:
> > Hi Guinevere,
> >
> > Please find some further comments below.
>
> Hi Christina!
>
> Thanks again for taking such a detailed look at this patch! I have some
> inlined comments, thanks for finding these issues!
No problem, it's always good to see new places in GDB. 😊
I still did not fully get the recording infrastructure TBH, but I am getting closer...
> >> -----Original Message-----
> >> From: Guinevere Larsen <guinevere@redhat.com>
> >> Sent: Donnerstag, 7. Mai 2026 19:38
> >> To: Schimpe, Christina <christina.schimpe@intel.com>; gdb-
> >> patches@sourceware.org
> >> Subject: Re: [PATCH v2 1/6] gdb/record: Refactor record history
> >>
> >> On 5/6/26 6:16 PM, Schimpe, Christina wrote:
> >>> Hi Guinevere,
> >>>
> >>> Thank you for working on this.
> >>> I found two items that might be worth looking at in more detail, but
> >>> apart from that it’s mostly minor nits. Please find my feedback below.
> >>>
> >>> I don’t have much experience with the record feature, so my review is
> >>> a bit slow here. To fully understand this patch, I probably need more
> time,
> >>> but I wanted to share the comments I already have. Sorry for chiming in
> >>> so late. I’ll try again tomorrow, or by Friday at the latest.
> >> Hi! Thank you for noting all the inconsistencies, I'll fix almost all of
> >> them before pushing!
> >>
> >> The one thing I don't think it's a good idea is to make the change from
> >> record_full_list -> record_full_log in this commit... mostly because it
> >> will introduce untold amounts of rebase conflicts. I'll introduce a
> >> following commit to this series that will make that renaming, though :)
> >> --
> >> Cheers,
> >> Guinevere Larsen
> >> It/she
> >>
> >>>> -----Original Message-----
> >>>> From: Guinevere Larsen <guinevere@redhat.com>
> >>>> Sent: Donnerstag, 23. April 2026 17:26
> >>>> To: gdb-patches@sourceware.org
> >>>> Cc: Guinevere Larsen <guinevere@redhat.com>
> >>>> Subject: [PATCH v2 1/6] gdb/record: Refactor record history
> >>>>
> >>>> This is the first step in a large refactor in how GDB keeps execution
> >>>> history. Rather than using a linked list where multiple entries can
> >>>> describe a single instruction, the history will now be stored in an
> >>>> std::deque, each instruction being one entry in the deque.
> >>>>
> >>>> The choice was initially to use an std::vector, but it would become
> >>>> unwieldy because it needs all the memory to be consecutive, which is
> >>>> hard for 200 thousand entries. Deque was picked because it was a nice
> >>>> midpoint between vector (maximum cache cohesion) and linked list
> >>>> (maximum ease of finding space to store more).
> >>>>
> >>>> Each instruction in memory will be now one record_full_instruction
> >>>> entry, which for this commit just contains a vector of
> >>>> record_full_entry for the effects of the instruction, and the data that
> >>>> was stored in the record_full_end entry (that is, the instruction number
> >>>> and the signal, if any).
> >>>>
> >>>> This change introduced a minimal performance improvement (what's
> >>>> important is that it isn't a degradation) and a reduction in the total
> >>>> memory footprint of roughly 20% if the entire history is used.
> >>>> ---
> >>>> gdb/aarch64-tdep.c | 2 -
> >>>> gdb/amd64-linux-tdep.c | 3 -
> >>>> gdb/arm-tdep.c | 2 -
> >>>> gdb/i386-linux-tdep.c | 3 -
> >>>> gdb/i386-tdep.c | 4 -
> >>>> gdb/loongarch-tdep.c | 2 -
> >>>> gdb/moxie-tdep.c | 2 -
> >>>> gdb/ppc-linux-tdep.c | 3 -
> >>>> gdb/record-full.c | 1180 ++++++++++++++++------------------------
> >>>> gdb/record-full.h | 1 -
> >>>> gdb/riscv-tdep.c | 3 -
> >>>> gdb/rs6000-tdep.c | 4 -
> >>>> gdb/s390-linux-tdep.c | 3 -
> >>>> gdb/s390-tdep.c | 2 -
> >>>> 14 files changed, 476 insertions(+), 738 deletions(-)
> >>>>
> >>>> diff --git a/gdb/aarch64-tdep.c b/gdb/aarch64-tdep.c
> >>>> index 4befaa2720d..a532992b1d8 100644
> >>>> --- a/gdb/aarch64-tdep.c
> >>>> +++ b/gdb/aarch64-tdep.c
> >>>> @@ -6210,8 +6210,6 @@ aarch64_process_record (struct gdbarch
> >> *gdbarch,
> >>>> struct regcache *regcache,
> >>>> aarch64_record.aarch64_mems[rec_no].len))
> >>>> ret = -1;
> >>>>
> >>>> - if (record_full_arch_list_add_end ())
> >>>> - ret = -1;
> >>>> }
> >>>>
> >>>> deallocate_reg_mem (&aarch64_record);
> >>>> diff --git a/gdb/amd64-linux-tdep.c b/gdb/amd64-linux-tdep.c
> >>>> index a5ac26654cf..9b23db72bbe 100644
> >>>> --- a/gdb/amd64-linux-tdep.c
> >>>> +++ b/gdb/amd64-linux-tdep.c
> >>>> @@ -1591,9 +1591,6 @@ amd64_linux_record_signal (struct gdbarch
> >>>> *gdbarch,
> >>>> + AMD64_LINUX_frame_size))
> >>>> return -1;
> >>>>
> >>>> - if (record_full_arch_list_add_end ())
> >>>> - return -1;
> >>>> -
> >>>> return 0;
> >>>> }
> >>>>
> >>>> diff --git a/gdb/arm-tdep.c b/gdb/arm-tdep.c
> >>>> index 08cce9dbad8..1ce0927f26b 100644
> >>>> --- a/gdb/arm-tdep.c
> >>>> +++ b/gdb/arm-tdep.c
> >>>> @@ -14911,8 +14911,6 @@ arm_process_record (struct gdbarch
> >> *gdbarch,
> >>>> struct regcache *regcache,
> >>>> }
> >>>> }
> >>>>
> >>>> - if (record_full_arch_list_add_end ())
> >>>> - ret = -1;
> >>>> }
> >>>>
> >>>>
> >>>> diff --git a/gdb/i386-linux-tdep.c b/gdb/i386-linux-tdep.c
> >>>> index 23aeccac9fc..4f33766fcdd 100644
> >>>> --- a/gdb/i386-linux-tdep.c
> >>>> +++ b/gdb/i386-linux-tdep.c
> >>>> @@ -949,9 +949,6 @@ i386_linux_record_signal (struct gdbarch
> >> *gdbarch,
> >>>> I386_LINUX_xstate +
> >>>> I386_LINUX_frame_size))
> >>>> return -1;
> >>>>
> >>>> - if (record_full_arch_list_add_end ())
> >>>> - return -1;
> >>>> -
> >>>> return 0;
> >>>> }
> >>>>
> >>>>
> >>>> diff --git a/gdb/i386-tdep.c b/gdb/i386-tdep.c
> >>>> index fa935b5fcdb..fee36b46a73 100644
> >>>> --- a/gdb/i386-tdep.c
> >>>> +++ b/gdb/i386-tdep.c
> >>>> @@ -5201,8 +5201,6 @@ i386_record_vex (struct i386_record_s *ir,
> >> uint8_t
> >>>> vex_w, uint8_t vex_r,
> >>>> }
> >>>>
> >>>> record_full_arch_list_add_reg (ir->regcache, ir-
> >>>>> regmap[X86_RECORD_REIP_REGNUM]);
> >>>> - if (record_full_arch_list_add_end ())
> >>>> - return -1;
> >>>>
> >>>> return 0;
> >>>> }
> >>>> @@ -8359,8 +8357,6 @@ Do you want to stop the program?"),
> >>>>
> >>>> /* In the future, maybe still need to deal with need_dasm. */
> >>>> I386_RECORD_FULL_ARCH_LIST_ADD_REG
> >> (X86_RECORD_REIP_REGNUM);
> >>>> - if (record_full_arch_list_add_end ())
> >>>> - return -1;
> >>>>
> >>>> return 0;
> >>>>
> >>>> diff --git a/gdb/loongarch-tdep.c b/gdb/loongarch-tdep.c
> >>>> index 225b1abb703..5ec6b2a48d0 100644
> >>>> --- a/gdb/loongarch-tdep.c
> >>>> +++ b/gdb/loongarch-tdep.c
> >>>> @@ -2789,8 +2789,6 @@ loongarch_process_record (struct gdbarch
> >>>> *gdbarch, struct regcache *regcache,
> >>>> LOONGARCH_PC_REGNUM))
> >>>> return -1;
> >>>>
> >>>> - if (record_full_arch_list_add_end ())
> >>>> - return -1;
> >>>> }
> >>>>
> >>>> return ret;
> >>>> diff --git a/gdb/moxie-tdep.c b/gdb/moxie-tdep.c
> >>>> index c8a04d21f59..2f8f0186488 100644
> >>>> --- a/gdb/moxie-tdep.c
> >>>> +++ b/gdb/moxie-tdep.c
> >>>> @@ -1040,8 +1040,6 @@ moxie_process_record (struct gdbarch
> >> *gdbarch,
> >>>> struct regcache *regcache,
> >>>>
> >>>> if (record_full_arch_list_add_reg (regcache, MOXIE_PC_REGNUM))
> >>>> return -1;
> >>>> - if (record_full_arch_list_add_end ())
> >>>> - return -1;
> >>>> return 0;
> >>>> }
> >>>>
> >>>> diff --git a/gdb/ppc-linux-tdep.c b/gdb/ppc-linux-tdep.c
> >>>> index 19698eaacbe..e2f53551709 100644
> >>>> --- a/gdb/ppc-linux-tdep.c
> >>>> +++ b/gdb/ppc-linux-tdep.c
> >>>> @@ -1565,9 +1565,6 @@ ppc_linux_record_signal (struct gdbarch
> >> *gdbarch,
> >>>> struct regcache *regcache,
> >>>> if (record_full_arch_list_add_mem (sp, SIGNAL_FRAMESIZE +
> >>>> sizeof_rt_sigframe))
> >>>> return -1;
> >>>>
> >>>> - if (record_full_arch_list_add_end ())
> >>>> - return -1;
> >>>> -
> >>>> return 0;
> >>>> }
> >>>>
> >>>> diff --git a/gdb/record-full.c b/gdb/record-full.c
> >>>> index 69d2c100e57..aac69cee17e 100644
> >>>> --- a/gdb/record-full.c
> >>>> +++ b/gdb/record-full.c
> >>> I think we should include vector, optional and deque directly.
> >>>
> >>>> @@ -72,20 +72,17 @@
> >>>> #define DEFAULT_RECORD_FULL_INSN_MAX_NUM 200000
> >>>>
> >>>> #define RECORD_FULL_IS_REPLAY \
> >>>> - (record_full_list->next || ::execution_direction == EXEC_REVERSE)
> >>>> + ( (record_full_next_insn != record_full_list.size ()) \
> >>> Nit: No whitespace after the first bracket:
> >>> => ((record_full_next_insn != record_full_list.size ()) \
> >>>
> >>>> + || ::execution_direction == EXEC_REVERSE)
> >>>>
> >>>> #define RECORD_FULL_FILE_MAGIC netorder32(0x20091016)
> >>>>
> >>>> /* These are the core structs of the process record functionality.
> >>>>
> >>>> A record_full_entry is a record of the value change of a register
> >>>> - ("record_full_reg") or a part of memory ("record_full_mem"). And
> each
> >>>> - instruction must have a struct record_full_entry ("record_full_end")
> >>>> - that indicates that this is the last struct record_full_entry of this
> >>>> - instruction.
> >>>> -
> >>>> - Each struct record_full_entry is linked to "record_full_list" by "prev"
> >>>> - and "next" pointers. */
> >>>> + ("record_full_reg") or a part of memory ("record_full_mem").
> >>>> + These are saved on the record_full_instruction struct, which also
> >>>> + contains some extra information, such as delivered signals. */
> >>>>
> >>>> struct record_full_mem_entry
> >>>> {
> >>>> @@ -112,47 +109,14 @@ struct record_full_reg_entry
> >>>> } u;
> >>>> };
> >>>>
> >>>> -struct record_full_end_entry
> >>>> -{
> >>>> - enum gdb_signal sigval;
> >>>> - ULONGEST insn_num;
> >>>> -};
> >>>> -
> >>>> enum record_full_type
> >>>> {
> >>>> - record_full_end = 0,
> >>>> record_full_reg,
> >>>> record_full_mem
> >>>> };
> >>>>
> >>>> -/* This is the data structure that makes up the execution log.
> >>>> -
> >>>> - The execution log consists of a single linked list of entries
> >>>> - of type "struct record_full_entry". It is doubly linked so that it
> >>>> - can be traversed in either direction.
> >>>> -
> >>>> - The start of the list is anchored by a struct called
> >>>> - "record_full_first". The pointer "record_full_list" either points
> >>>> - to the last entry that was added to the list (in record mode), or to
> >>>> - the next entry in the list that will be executed (in replay mode).
> >>>> -
> >>>> - Each list element (struct record_full_entry), in addition to next
> >>>> - and prev pointers, consists of a union of three entry types: mem,
> >>>> - reg, and end. A field called "type" determines which entry type is
> >>>> - represented by a given list element.
> >>>> -
> >>>> - Each instruction that is added to the execution log is represented
> >>>> - by a variable number of list elements ('entries'). The instruction
> >>>> - will have one "reg" entry for each register that is changed by
> >>>> - executing the instruction (including the PC in every case). It
> >>>> - will also have one "mem" entry for each memory change. Finally,
> >>>> - each instruction will have an "end" entry that separates it from
> >>>> - the changes associated with the next instruction. */
> >>>> -
> >>>> struct record_full_entry
> >>>> {
> >>>> - struct record_full_entry *prev;
> >>>> - struct record_full_entry *next;
> >>>> enum record_full_type type;
> >>>> union
> >>>> {
> >>>> @@ -160,11 +124,31 @@ struct record_full_entry
> >>>> struct record_full_reg_entry reg;
> >>>> /* mem */
> >>>> struct record_full_mem_entry mem;
> >>>> - /* end */
> >>>> - struct record_full_end_entry end;
> >>>> } u;
> >>>> };
> >>>>
> >>>> +/* This is the main structure that comprises the execution log.
> >>>> + Each instruction is comprised of:
> >>>> + * The instruction number: How many instructions were recorded
> before
> >>>> + this one;
> >>>> + * sigval: Whether the inferior received a signal while the following
> >>>> + instruction was being recorded;
> > It might be worth describing in the comment in which cases this does not
> > have a value, to point out the reason why this is now optional.
> > As I understand it before this patch we used GDB_SIGNAL_0 for this case, is
> that right?
>
> well, yeah, we used to use GDB_SIGNAL_0, but I think it is better to
> explicitly say "there was no signal" other than say "the signal was 0"
> which is treated as a nothing. It's the problem with NULL/nullptr,
> versus languages where nullptrs aren't allowed and instead accessing an
> unset pointer is just disallowed. I just want to add more mindful usage
> of it to make code safer.
>
> So I don't think it makes sense to add in a comment why it changed, when
> we instead needed a comment earlier about how to deal with "no signal
> was delivered"
Yes, fine with me.
> >>>> + * effects: A list of record_full_entry structures, each of which
> >>>> + describing one effect that the instruction has on the inferior.
> >>>> +
> >>>> + Note, the signal is stored in the previous instruction for historical
> >>>> + reasons. This is how it was first implemented, and no one has gotten
> >>>> + around to changing it yet. */
> >>>> +
> >>>> +struct record_full_instruction
> >>>> +{
> >>>> + /* This might be different from the index if
> >>>> + we had to remove the first few instructions. */
> >>>> + uint32_t insn_num;
> >>>> + std::optional<gdb_signal> sigval;
> >>>> + std::vector<record_full_entry> effects;
> >>>> +};
> >>>> +
> >>>> /* If true, query if PREC cannot record memory
> >>>> change of next instruction. */
> >>>> bool record_full_memory_query = false;
> >>>> @@ -181,27 +165,25 @@ static detached_regcache
> >>>> *record_full_core_regbuf = NULL;
> >>>> static std::vector<target_section> record_full_core_sections;
> >>>> static struct record_full_core_buf_entry *record_full_core_buf_list =
> >> NULL;
> >>>> -/* The following variables are used for managing the linked list that
> >>>> - represents the execution log.
> >>>> +/* The following variables are used for managing the history of
> executed
> >>>> + instructions from the inferior.
> >>>>
> >>>> - record_full_first is the anchor that holds down the beginning of
> >>>> - the list.
> >>>> + record_full_list contains all instructions that were fully executed and
> >>>> + saved to the log, so that we can replay the execution.
> >>>>
> >>>> - record_full_list serves two functions:
> >>>> - 1) In record mode, it anchors the end of the list.
> >>>> - 2) In replay mode, it traverses the list and points to
> >>>> - the next instruction that must be emulated.
> >>>> + record_full_next_insn always points to the next instruction that
> would
> >>>> + be executed if the inferior executes forward. In the special case when
> >>>> + the inferior is not replaying, record_full_next_insn points past the
> >>>> + end of the history.
> >>>>
> >>>> - record_full_arch_list_head and record_full_arch_list_tail are used
> >>>> - to manage a separate list, which is used to build up the change
> >>>> - elements of the currently executing instruction during record mode.
> >>>> - When this instruction has been completely annotated in the "arch
> >>>> - list", it will be appended to the main execution log. */
> >>>> + record_full_incomplete_instruction holds a partial instruction, while
> >>>> + the lower target is disassembling the instruction, or as partial xfers
> are
> >>>> + happening. It is manipulated by the "arch list" functions for historical
> >>>> + reasons. */
> >>>>
> >>>> -static struct record_full_entry record_full_first;
> >>>> -static struct record_full_entry *record_full_list = &record_full_first;
> >>>> -static struct record_full_entry *record_full_arch_list_head = NULL;
> >>>> -static struct record_full_entry *record_full_arch_list_tail = NULL;
> >>>> +static std::deque<record_full_instruction> record_full_list;
> >>> Given that this is not a list anymore I wonder if we should better call this
> >> sth. like
> >>> record_full_history or record_full_log or even simply
> >> recorded_instructions?
> >>>> +static record_full_instruction record_full_incomplete_instruction;
> >>>> +int record_full_next_insn;
> > Any particular reason why this is not static?
> no, I'll make that change.
> >
> >>>> /* true ask user. false auto delete the last struct record_full_entry. */
> >>>> static bool record_full_stop_at_limit = true;
> >>>> @@ -361,6 +343,14 @@ record_full_target::kill ()
> >>>> record_kill (this);
> >>>> }
> >>>>
> >>>> +static void
> >>>> +record_full_reset_incomplete ()
> >>>> +{
> >>>> + record_full_incomplete_instruction.effects.clear ();
> >>>> + record_full_incomplete_instruction.sigval.reset ();
> >>>> + record_full_incomplete_instruction.insn_num = 0;
> >>>> +}
> >>>> +
> >>>> /* See record-full.h. */
> >>>>
> >>>> int
> >>>> @@ -390,156 +380,120 @@ static struct cmd_list_element
> >>>> *show_record_full_cmdlist;
> >>>> /* Command list for "record full". */
> >>>> static struct cmd_list_element *record_full_cmdlist;
> >>>>
> >>>> -static void record_full_goto_insn (struct record_full_entry *entry,
> >>>> +static void record_full_goto_insn (size_t target_insn,
> >>>> enum exec_direction_kind dir);
> >>>>
> >>>> -/* Alloc and free functions for record_full_reg, record_full_mem, and
> >>>> - record_full_end entries. */
> >>>> +/* Initialization and cleanup functions for record_full_reg and
> >>>> + record_full_mem entries. */
> >>>>
> >>>> -/* Alloc a record_full_reg record entry. */
> >>>> +/* Init a record_full_reg record entry. */
> >>>>
> >>>> -static inline struct record_full_entry *
> >>>> -record_full_reg_alloc (struct regcache *regcache, int regnum)
> >>>> +static inline struct record_full_entry
> >>>> +record_full_reg_init (struct regcache *regcache, int regnum)
> >>>> {
> >>>> - struct record_full_entry *rec;
> >>>> + struct record_full_entry rec;
> >>>> struct gdbarch *gdbarch = regcache->arch ();
> >>>>
> >>>> - rec = XCNEW (struct record_full_entry);
> >>>> - rec->type = record_full_reg;
> >>>> - rec->u.reg.num = regnum;
> >>>> - rec->u.reg.len = register_size (gdbarch, regnum);
> >>>> - if (rec->u.reg.len > sizeof (rec->u.reg.u.buf))
> >>>> - rec->u.reg.u.ptr = (gdb_byte *) xmalloc (rec->u.reg.len);
> >>>> + rec.type = record_full_reg;
> >>>> + rec.u.reg.num = regnum;
> >>>> + rec.u.reg.len = register_size (gdbarch, regnum);
> >>>> + if (rec.u.reg.len > sizeof (rec.u.reg.u.buf))
> >>>> + rec.u.reg.u.ptr = (gdb_byte *) xmalloc (rec.u.reg.len);
> >>>>
> >>>> return rec;
> >>>> }
> >>>>
> >>>> -/* Free a record_full_reg record entry. */
> >>>> +/* Cleanup a record_full_reg record entry. */
> >>>>
> >>>> static inline void
> >>>> -record_full_reg_release (struct record_full_entry *rec)
> >>>> +record_full_reg_cleanup (struct record_full_entry rec)
> >>>> {
> >>>> - gdb_assert (rec->type == record_full_reg);
> >>>> - if (rec->u.reg.len > sizeof (rec->u.reg.u.buf))
> >>>> - xfree (rec->u.reg.u.ptr);
> >>>> - xfree (rec);
> >>>> + gdb_assert (rec.type == record_full_reg);
> >>>> + if (rec.u.reg.len > sizeof (rec.u.reg.u.buf))
> >>>> + xfree (rec.u.reg.u.ptr);
> >>>> }
> >>>>
> >>>> -/* Alloc a record_full_mem record entry. */
> >>>> +/* Init a record_full_mem record entry. */
> >>>>
> >>>> -static inline struct record_full_entry *
> >>>> -record_full_mem_alloc (CORE_ADDR addr, int len)
> >>>> +static inline struct record_full_entry
> >>>> +record_full_mem_init (CORE_ADDR addr, int len)
> >>>> {
> >>>> - struct record_full_entry *rec;
> >>>> + struct record_full_entry rec;
> >>>>
> >>>> - rec = XCNEW (struct record_full_entry);
> >>>> - rec->type = record_full_mem;
> >>>> - rec->u.mem.addr = addr;
> >>>> - rec->u.mem.len = len;
> >>>> - if (rec->u.mem.len > sizeof (rec->u.mem.u.buf))
> >>>> - rec->u.mem.u.ptr = (gdb_byte *) xmalloc (len);
> >>>> + rec.type = record_full_mem;
> >>>> + rec.u.mem.addr = addr;
> >>>> + rec.u.mem.len = len;
> >>>> + if (rec.u.mem.len > sizeof (rec.u.mem.u.buf))
> >>>> + rec.u.mem.u.ptr = (gdb_byte *) xmalloc (len);
> >>>> + rec.u.mem.mem_entry_not_accessible = 0;
> >>>>
> >>>> return rec;
> >>>> }
> >>>>
> >>>> -/* Free a record_full_mem record entry. */
> >>>> +/* Cleanup a record_full_mem record entry. */
> >>>>
> >>>> static inline void
> >>>> -record_full_mem_release (struct record_full_entry *rec)
> >>>> -{
> >>>> - gdb_assert (rec->type == record_full_mem);
> >>>> - if (rec->u.mem.len > sizeof (rec->u.mem.u.buf))
> >>>> - xfree (rec->u.mem.u.ptr);
> >>>> - xfree (rec);
> >>>> -}
> >>>> -
> >>>> -/* Alloc a record_full_end record entry. */
> >>>> -
> >>>> -static inline struct record_full_entry *
> >>>> -record_full_end_alloc (void)
> >>>> +record_full_mem_cleanup (struct record_full_entry rec)
> >>>> {
> >>>> - struct record_full_entry *rec;
> >>>> -
> >>>> - rec = XCNEW (struct record_full_entry);
> >>>> - rec->type = record_full_end;
> >>>> -
> >>>> - return rec;
> >>>> + gdb_assert (rec.type == record_full_mem);
> >>>> + if (rec.u.mem.len > sizeof (rec.u.mem.u.buf))
> >>>> + xfree (rec.u.mem.u.ptr);
> >>>> }
> >>>>
> >>>> -/* Free a record_full_end record entry. */
> >>>> +/* Free one record entry, any type. */
> >>>>
> >>>> static inline void
> >>>> -record_full_end_release (struct record_full_entry *rec)
> >>>> -{
> >>>> - xfree (rec);
> >>>> -}
> >>>> -
> >>>> -/* Free one record entry, any type.
> >>>> - Return entry->type, in case caller wants to know. */
> >>>> -
> >>>> -static inline enum record_full_type
> >>>> -record_full_entry_release (struct record_full_entry *rec)
> >>>> +record_full_entry_cleanup (struct record_full_entry rec)
> >>>> {
> >>>> - enum record_full_type type = rec->type;
> >>>>
> >>>> - switch (type) {
> >>>> + switch (rec.type) {
> >>>> case record_full_reg:
> >>>> - record_full_reg_release (rec);
> >>>> + record_full_reg_cleanup (rec);
> >>>> break;
> >>>> case record_full_mem:
> >>>> - record_full_mem_release (rec);
> >>>> - break;
> >>>> - case record_full_end:
> >>>> - record_full_end_release (rec);
> >>>> + record_full_mem_cleanup (rec);
> >>>> break;
> >>>> }
> >>>> - return type;
> >>>> }
> >>>>
> >>>> -/* Free all record entries in list pointed to by REC. */
> >>>> -
> >>>> static void
> >>>> -record_full_list_release (struct record_full_entry *rec)
> >>>> +record_full_reset_history ()
> >>>> {
> >>>> - if (!rec)
> >>>> - return;
> >>>> -
> >>>> - while (rec->next)
> >>>> - rec = rec->next;
> >>>> + record_full_insn_num = 0;
> >>>> + record_full_insn_count = 0;
> >>>> + record_full_next_insn = 0;
> >>>>
> >>>> - while (rec->prev)
> >>>> + for (auto &insn : record_full_list)
> >>>> {
> >>>> - rec = rec->prev;
> >>>> - record_full_entry_release (rec->next);
> >>>> + for (auto &entry : insn.effects)
> >>>> + record_full_entry_cleanup (entry);
> >>>> }
> >>>>
> >>>> - if (rec == &record_full_first)
> >>>> - {
> >>>> - record_full_insn_num = 0;
> >>>> - record_full_first.next = NULL;
> >>>> - }
> >>>> - else
> >>>> - record_full_entry_release (rec);
> >>>> + record_full_list.clear ();
> >>>> }
> >>>>
> >>>> -/* Free all record entries forward of the given list position. */
> >>>> -
> >>>> static void
> >>>> -record_full_list_release_following (struct record_full_entry *rec)
> >>>> +record_full_list_release_following (int index)
> >>>> {
> >>>> - struct record_full_entry *tmp = rec->next;
> >>>> -
> >>>> - rec->next = NULL;
> >>>> - while (tmp)
> >>>> + for (int i = record_full_list.size () - 1; i > index; i--)
> >>>> {
> >>>> - rec = tmp->next;
> >>>> - if (record_full_entry_release (tmp) == record_full_end)
> >>>> - {
> >>>> - record_full_insn_num--;
> >>>> - record_full_insn_count--;
> >>>> - }
> >>>> - tmp = rec;
> >>>> + for (auto &entry : record_full_list[i].effects)
> >>>> + record_full_entry_cleanup (entry);
> >>>> + record_full_list.pop_back ();
> >>>> }
> >>>> + /* Set the next instruction to be past the end of the log so we
> >>>> + start recording if the user moves forward again. */
> >>>> + record_full_next_insn = index;
> >>>> +}
> >>>> +static void
> >>>> +record_full_save_instruction ()
> > A function comment would be nice.
> >
> >>>> +{
> >>>> + ++record_full_insn_count;
> >>>> + record_full_incomplete_instruction.insn_num =
> record_full_insn_count;
> >>>> + record_full_incomplete_instruction.effects.shrink_to_fit ();
> >>>> + record_full_list.push_back (record_full_incomplete_instruction);
> > I think this line will at some point call the default copy constructor of
> record_full_mem_entry
> > and record_full_reg_entry, which have those buffers:
> >
> > gdb_byte buf[sizeof (gdb_byte *)];
> >
> > IIUC you'll only have a shallow copy. Should we use a std::move instead
> here?
> Might be worth, yeah...
> >
> > I further wonder if this problem might be related to the double free issues
> you
> > describe in patch #3. Would you mind checking?
> I did check it! When I was working on patch #3, I disabled copy
> construction, only allowed move constructor/assignment because I
> specifically thought that the vector push_back was the reason for the
> double frees, but it still happened.
That's weird, it would have perfectly explained it.
So with std::move we still have this problem?
Would you mind sharing some backtrace of this double free error ?
> > And if you add the destructor, I think it would make sense to add a copy
> constructor etc., too:
> > https://en.cppreference.com/cpp/language/rule_of_three
> >
> >>>> + record_full_next_insn++;
> >>>> }
> >>>>
> >>>> /* Delete the first instruction from the beginning of the log, to make
> >>>> @@ -550,52 +504,22 @@ record_full_list_release_following (struct
> >>>> record_full_entry *rec)
> >>>> static void
> >>>> record_full_list_release_first (void)
> >>>> {
> >>>> - struct record_full_entry *tmp;
> >>>> -
> >>>> - if (!record_full_first.next)
> >>>> + if (record_full_list.empty ())
> >>>> return;
> >>>>
> >>>> - /* Loop until a record_full_end. */
> >>>> - while (1)
> >>>> - {
> >>>> - /* Cut record_full_first.next out of the linked list. */
> >>>> - tmp = record_full_first.next;
> >>>> - record_full_first.next = tmp->next;
> >>>> - tmp->next->prev = &record_full_first;
> >>>> -
> >>>> - /* tmp is now isolated, and can be deleted. */
> >>>> - if (record_full_entry_release (tmp) == record_full_end)
> >>>> - break; /* End loop at first record_full_end. */
> >>>> + for (auto &entry : record_full_list[0].effects)
> >>>> + record_full_entry_cleanup (entry);
> >>>>
> >>>> - if (!record_full_first.next)
> >>>> - {
> >>>> - gdb_assert (record_full_insn_num == 1);
> >>>> - break; /* End loop when list is empty. */
> >>>> - }
> >>>> - }
> >>>> + record_full_list.pop_front ();
> >>>> + --record_full_next_insn;
> >>>> }
> >>>>
> >>>> /* Add a struct record_full_entry to record_full_arch_list. */
> >>>>
> >>>> static void
> >>>> -record_full_arch_list_add (struct record_full_entry *rec)
> >>>> +record_full_arch_list_add (struct record_full_entry &rec)
> >>>> {
> >>>> - if (record_debug > 1)
> >>>> - gdb_printf (gdb_stdlog,
> >>>> - "Process record: record_full_arch_list_add %s.\n",
> >>>> - host_address_to_string (rec));
> >>>> -
> >>>> - if (record_full_arch_list_tail)
> >>>> - {
> >>>> - record_full_arch_list_tail->next = rec;
> >>>> - rec->prev = record_full_arch_list_tail;
> >>>> - record_full_arch_list_tail = rec;
> >>>> - }
> >>>> - else
> >>>> - {
> >>>> - record_full_arch_list_head = rec;
> >>>> - record_full_arch_list_tail = rec;
> >>>> - }
> >>>> + record_full_incomplete_instruction.effects.push_back (rec);
> >>>> }
> >>>>
> >>>> /* Return the value storage location of a record entry. */
> >>>> @@ -613,7 +537,6 @@ record_full_get_loc (struct record_full_entry
> *rec)
> >>>> return rec->u.reg.u.ptr;
> >>>> else
> >>>> return rec->u.reg.u.buf;
> >>>> - case record_full_end:
> >>>> default:
> >>>> gdb_assert_not_reached ("unexpected record_full_entry type");
> >>>> return NULL;
> >>>> @@ -625,7 +548,7 @@ record_full_get_loc (struct record_full_entry
> *rec)
> >>>> int
> >>>> record_full_arch_list_add_reg (struct regcache *regcache, int regnum)
> >>>> {
> >>>> - struct record_full_entry *rec;
> >>>> + struct record_full_entry rec;
> >>> I think we can omit the struct keyword here (there are some more
> >> occurrences in this patch).
> >>>> if (record_debug > 1)
> >>>> gdb_printf (gdb_stdlog,
> >>>> @@ -633,9 +556,9 @@ record_full_arch_list_add_reg (struct regcache
> >>>> *regcache, int regnum)
> >>>> "record list.\n",
> >>>> regnum);
> >>>>
> >>>> - rec = record_full_reg_alloc (regcache, regnum);
> >>>> + rec = record_full_reg_init (regcache, regnum);
> >>>>
> >>>> - regcache->cooked_read (regnum, record_full_get_loc (rec));
> >>>> + regcache->cooked_read (regnum, record_full_get_loc (&rec));
> >>>>
> >>>> record_full_arch_list_add (rec);
> >>>>
> >>>> @@ -648,7 +571,7 @@ record_full_arch_list_add_reg (struct regcache
> >>>> *regcache, int regnum)
> >>>> int
> >>>> record_full_arch_list_add_mem (CORE_ADDR addr, int len)
> >>>> {
> >>>> - struct record_full_entry *rec;
> >>>> + struct record_full_entry rec;
> >>>>
> >>>> if (record_debug > 1)
> >>>> gdb_printf (gdb_stdlog,
> >>>> @@ -659,12 +582,12 @@ record_full_arch_list_add_mem
> (CORE_ADDR
> >> addr,
> >>>> int len)
> >>>> if (!addr) /* FIXME: Why? Some arch must permit it... */
> >>>> return 0;
> >>>>
> >>>> - rec = record_full_mem_alloc (addr, len);
> >>>> + rec = record_full_mem_init (addr, len);
> >>>>
> >>>> if (record_read_memory (current_inferior ()->arch (), addr,
> >>>> - record_full_get_loc (rec), len))
> >>>> + record_full_get_loc (&rec), len))
> >>>> {
> >>>> - record_full_mem_release (rec);
> >>>> + record_full_mem_cleanup (rec);
> >>>> return -1;
> >>>> }
> >>>>
> >>>> @@ -673,27 +596,6 @@ record_full_arch_list_add_mem (CORE_ADDR
> >> addr,
> >>>> int len)
> >>>> return 0;
> >>>> }
> >>>>
> >>>> -/* Add a record_full_end type struct record_full_entry to
> >>>> - record_full_arch_list. */
> >>>> -
> >>>> -int
> >>>> -record_full_arch_list_add_end (void)
> >>>> -{
> >>>> - struct record_full_entry *rec;
> >>>> -
> >>>> - if (record_debug > 1)
> >>>> - gdb_printf (gdb_stdlog,
> >>>> - "Process record: add end to arch list.\n");
> >>>> -
> >>>> - rec = record_full_end_alloc ();
> >>>> - rec->u.end.sigval = GDB_SIGNAL_0;
> >>>> - rec->u.end.insn_num = ++record_full_insn_count;
> >>>> -
> >>>> - record_full_arch_list_add (rec);
> >>>> -
> >>>> - return 0;
> >>>> -}
> >>>> -
> >>>> static void
> >>>> record_full_check_insn_num (void)
> >>>> {
> >>>> @@ -725,8 +627,7 @@ record_full_message (struct regcache
> *regcache,
> >>>> enum gdb_signal signal)
> >>>>
> >>>> try
> >>>> {
> >>>> - record_full_arch_list_head = NULL;
> >>>> - record_full_arch_list_tail = NULL;
> >>>> + record_full_reset_incomplete ();
> >>>>
> >>>> /* Check record_full_insn_num. */
> >>>> record_full_check_insn_num ();
> >>>> @@ -746,20 +647,16 @@ record_full_message (struct regcache
> >> *regcache,
> >>>> enum gdb_signal signal)
> >>>> the user says something different, like "deliver this signal"
> >>>> during the replay mode).
> >>>>
> >>>> - User should understand that nothing he does during the replay
> >>>> - mode will change the behavior of the child. If he tries,
> >>>> + User should understand that nothing they do during the replay
> >>>> + mode will change the behavior of the child. If they try,
> >>>> then that is a user error.
> >>>>
> >>>> But we should still deliver the signal to gdb during the replay,
> >>>> if we delivered it during the recording. Therefore we should
> >>>> record the signal during record_full_wait, not
> >>>> record_full_resume. */
> >>>> - if (record_full_list != &record_full_first) /* FIXME better way
> >>>> - to check */
> >>>> - {
> >>>> - gdb_assert (record_full_list->type == record_full_end);
> >>>> - record_full_list->u.end.sigval = signal;
> >>>> - }
> >>>> + if (signal != GDB_SIGNAL_0)
> >>>> + record_full_list[record_full_next_insn - 1].sigval = signal;
> > Similar comment as already in my earlier review:
> > Can record_full_next_insn be == 0 here or may record_full_list be empty ?
> Oh you're right. This is probably because I misunderstood the order of
> operations and was saving it to the current one, not the previous one,
> and when I fixed that I forgot to check the original
> >
> > I think it might be worth checking the patch if there are more similar issues.
> > The old patch had more guards to check this.
> yeah good point, I'll look through the changes and see if I notice it
> anywhere else.
> >
> > And I noticed in some other locations you cast it:
> >
> > if (sigval != GDB_SIGNAL_0)
> > record_full_incomplete_instruction.sigval = (gdb_signal) sigval;
> >
> > Not sure if this is necessary or not, but it might be for checking and making
> it consistent?
> I cast it in the other location because it is reading from the BFD and
> so sigval is declared as uint8_t, not as gdb_signal.
> > And is it intended that now we don't clear sigval anymore?
> >
> > Shouldn't we set it to std::nullopt in case signal == GDB_SIGNAL_0, to
> match the original
> > behaviour?
>
> yeah this is a mistake. The plan was that record_full_save_instruction
> clears the incomplete instruction, but I apparently forgot that.
>
> With that, it should always be clear so we won't need to explicitly set
> it to nullopt.
>
> I'll update the correct function.
>
> >
> >>>> if (signal == GDB_SIGNAL_0
> >>>> || !gdbarch_process_record_signal_p (gdbarch))
> >>>> @@ -778,13 +675,11 @@ record_full_message (struct regcache
> >> *regcache,
> >>>> enum gdb_signal signal)
> >>>> }
> >>>> catch (const gdb_exception &ex)
> >>>> {
> >>>> - record_full_list_release (record_full_arch_list_tail);
> >>>> + record_full_reset_incomplete ();
> >>>> throw;
> >>>> }
> >>>>
> >>>> - record_full_list->next = record_full_arch_list_head;
> >>>> - record_full_arch_list_head->prev = record_full_list;
> >>>> - record_full_list = record_full_arch_list_tail;
> >>>> + record_full_save_instruction ();
> >>>>
> >>>> if (record_full_insn_num == record_full_insn_max_num)
> >>>> record_full_list_release_first ();
> >>>> @@ -829,9 +724,9 @@ static enum target_stop_reason
> >>>> record_full_stop_reason
> >>>> entries and memory entries, followed by an 'end' entry. */
> >>>>
> >>>> static inline void
> >>>> -record_full_exec_insn (struct regcache *regcache,
> >>>> - struct gdbarch *gdbarch,
> >>>> - struct record_full_entry *entry)
> >>>> +record_full_exec_entry (struct regcache *regcache,
> >>>> + struct gdbarch *gdbarch,
> >>>> + struct record_full_entry *entry)
> >>> Nit: omit struct keywords
> >>> And there are some more places in this series/patch, but I will stop
> >> commenting
> >>> now on all of them.
> >>>
> >>>> {
> >>>> switch (entry->type)
> >>>> {
> >>>> @@ -909,6 +804,15 @@ record_full_exec_insn (struct regcache
> >> *regcache,
> >>>> }
> >>>> }
> >>>>
> >>>> +static inline void
> >>>> +record_full_exec_insn (struct regcache *regcache,
> >>>> + struct gdbarch *gdbarch,
> >>>> + record_full_instruction &insn)
> >>>> +{
> >>>> + for (auto &entry : insn.effects)
> >>>> + record_full_exec_entry (regcache, gdbarch, &entry);
> >>>> +}
> >>>> +
> >>>> static void record_full_restore (struct bfd &cbfd);
> >>>>
> >>>> /* Asynchronous signal handle registered as event loop source for
> when
> >>>> @@ -983,10 +887,7 @@ record_full_open (const char *args, int
> from_tty)
> >>>> record_preopen ();
> >>>>
> >>>> /* Reset */
> >>>> - record_full_insn_num = 0;
> >>>> - record_full_insn_count = 0;
> >>>> - record_full_list = &record_full_first;
> >>>> - record_full_list->next = NULL;
> >>>> + record_full_reset_history ();
> >>>>
> >>>> bfd *cbfd = get_inferior_core_bfd (current_inferior ());
> >>>> if (cbfd != nullptr)
> >>>> @@ -1014,7 +915,7 @@ record_full_base_target::close ()
> >>>> if (record_debug)
> >>>> gdb_printf (gdb_stdlog, "Process record: record_full_close\n");
> >>>>
> >>>> - record_full_list_release (record_full_list);
> >>>> + record_full_reset_history ();
> >>>>
> >>>> /* Release record_full_core_regbuf. */
> >>>> if (record_full_core_regbuf)
> >>>> @@ -1313,7 +1214,6 @@ record_full_wait_1 (struct target_ops *ops,
> >>>> struct gdbarch *gdbarch = regcache->arch ();
> >>>> const address_space *aspace = current_inferior ()->aspace.get ();
> >>>> int continue_flag = 1;
> >>>> - int first_record_full_end = 1;
> >>>>
> >>>> try
> >>>> {
> >>>> @@ -1322,7 +1222,6 @@ record_full_wait_1 (struct target_ops *ops,
> >>>> record_full_stop_reason = TARGET_STOPPED_BY_NO_REASON;
> >>>> status->set_stopped (GDB_SIGNAL_0);
> >>>>
> >>>> - /* Check breakpoint when forward execute. */
> >>>> if (execution_direction == EXEC_FORWARD)
> >>>> {
> >>>> tmp_pc = regcache_read_pc (regcache);
> >>>> @@ -1330,8 +1229,7 @@ record_full_wait_1 (struct target_ops *ops,
> >>>>
> >>>> &record_full_stop_reason))
> >>>> {
> >>>> if (record_debug)
> >>>> - gdb_printf (gdb_stdlog,
> >>>> - "Process record: break at %s.\n",
> >>>> + gdb_printf (gdb_stdlog, "Process record: break at %s.\n",
> >>>> paddress (gdbarch, tmp_pc));
> >>>> goto replay_out;
> >>>> }
> >>>> @@ -1344,10 +1242,10 @@ record_full_wait_1 (struct target_ops
> *ops,
> >>>> the signal. */
> >>>> target_terminal::ours ();
> >>>>
> >>>> - /* In EXEC_FORWARD mode, record_full_list points to the tail of
> >> prev
> >>>> - instruction. */
> >>>> - if (execution_direction == EXEC_FORWARD && record_full_list-
> >>> next)
> >>>> - record_full_list = record_full_list->next;
> >>>> + /* In EXEC_FORWARD mode, record_full_next_insn is the next
> >>>> + instruction to be executed. */
> >>>> + if (execution_direction == EXEC_REVERSE)
> >>>> + record_full_next_insn--;
> >>>>
> >>>> /* Loop over the record_full_list, looking for the next place to
> >>>> stop. */
> >>>> @@ -1355,108 +1253,92 @@ record_full_wait_1 (struct target_ops
> *ops,
> >>>> {
> >>>> /* Check for beginning and end of log. */
> >>>> if (execution_direction == EXEC_REVERSE
> >>>> - && record_full_list == &record_full_first)
> >>>> + && record_full_next_insn < 0)
> >>>> {
> >>>> /* Hit beginning of record log in reverse. */
> >>>> status->set_no_history ();
> >>>> + record_full_next_insn = 0;
> >>>> break;
> >>>> }
> >>>> if (execution_direction != EXEC_REVERSE
> >>>> - && !record_full_list->next)
> >>>> + && record_full_next_insn == record_full_list.size ())
> >>>> {
> >>>> /* Hit end of record log going forward. */
> >>>> status->set_no_history ();
> >>>> break;
> >>>> }
> >>>>
> >>>> - record_full_exec_insn (regcache, gdbarch, record_full_list);
> >>>> + record_full_exec_insn
> >>>> + (regcache, gdbarch,
> >>>> + record_full_list[record_full_next_insn]);
> >>>>
> >>>> - if (record_full_list->type == record_full_end)
> >>>> + /* step */
> >>>> + if (record_full_resume_step)
> >>>> {
> >>>> if (record_debug > 1)
> >>>> - gdb_printf
> >>>> - (gdb_stdlog,
> >>>> - "Process record: record_full_end %s to "
> >>>> - "inferior.\n",
> >>>> - host_address_to_string (record_full_list));
> >>>> -
> >>>> - if (first_record_full_end
> >>>> - && execution_direction == EXEC_REVERSE)
> >>>> - {
> >>>> - /* When reverse execute, the first
> >>>> - record_full_end is the part of current
> >>>> - instruction. */
> >>>> - first_record_full_end = 0;
> >>>> - }
> >>>> - else
> >>>> - {
> >>>> - /* In EXEC_REVERSE mode, this is the
> >>>> - record_full_end of prev instruction. In
> >>>> - EXEC_FORWARD mode, this is the
> >>>> - record_full_end of current instruction. */
> >>>> - /* step */
> >>>> - if (record_full_resume_step)
> >>>> - {
> >>>> - if (record_debug > 1)
> >>>> - gdb_printf (gdb_stdlog,
> >>>> - "Process record: step.\n");
> >>>> - continue_flag = 0;
> >>>> - }
> >>>> -
> >>>> - /* check breakpoint */
> >>>> - tmp_pc = regcache_read_pc (regcache);
> >>>> - if (record_check_stopped_by_breakpoint
> >>>> - (aspace, tmp_pc, &record_full_stop_reason))
> >>>> - {
> >>>> - if (record_debug)
> >>>> - gdb_printf (gdb_stdlog,
> >>>> - "Process record: break "
> >>>> - "at %s.\n",
> >>>> - paddress (gdbarch, tmp_pc));
> >>>> + gdb_printf (gdb_stdlog,
> >>>> + "Process record: step.\n");
> >>>> + continue_flag = 0;
> >>>> + }
> >>>>
> >>>> - continue_flag = 0;
> >>>> - }
> >>>> + /* check breakpoint */
> >>>> + tmp_pc = regcache_read_pc (regcache);
> >>>> + if (record_check_stopped_by_breakpoint
> >>>> + (aspace, tmp_pc, &record_full_stop_reason))
> >>>> + {
> >>>> + if (record_debug)
> >>>> + gdb_printf (gdb_stdlog,
> >>>> + "Process record: break "
> >>>> + "at %s.\n",
> >>>> + paddress (gdbarch, tmp_pc));
> >>>>
> >>>> - if (record_full_stop_reason
> >>>> - == TARGET_STOPPED_BY_WATCHPOINT)
> >>>> - {
> >>>> - if (record_debug)
> >>>> - gdb_printf (gdb_stdlog,
> >>>> - "Process record: hit hw "
> >>>> - "watchpoint.\n");
> >>>> - continue_flag = 0;
> >>>> - }
> >>>> - /* Check target signal */
> >>>> - if (record_full_list->u.end.sigval != GDB_SIGNAL_0)
> >>>> - /* FIXME: better way to check */
> >>>> - continue_flag = 0;
> >>>> - }
> >>>> + continue_flag = 0;
> >>>> }
> >>>>
> >>>> - if (continue_flag)
> >>>> + if (record_full_stop_reason
> >>>> + == TARGET_STOPPED_BY_WATCHPOINT)
> >>>> {
> >>>> - if (execution_direction == EXEC_REVERSE)
> >>>> - {
> >>>> - if (record_full_list->prev)
> >>>> - record_full_list = record_full_list->prev;
> >>>> - }
> >>>> - else
> >>>> - {
> >>>> - if (record_full_list->next)
> >>>> - record_full_list = record_full_list->next;
> >>>> - }
> >>>> + if (record_debug)
> >>>> + gdb_printf (gdb_stdlog,
> >>>> + "Process record: hit hw "
> >>>> + "watchpoint.\n");
> >>>> + continue_flag = 0;
> >>>> }
> >>>> + if (record_full_list[record_full_next_insn].sigval.has_value ())
> >>>> + continue_flag = 0;
> >>>> +
> >>>> + if (execution_direction == EXEC_REVERSE)
> >>>> + record_full_next_insn--;
> >>>> + else
> >>>> + record_full_next_insn++;
> >>>> }
> >>>> while (continue_flag);
> >>>>
> >>>> + if (record_full_next_insn < 0)
> >>>> + {
> >>>> + gdb_assert (execution_direction == EXEC_REVERSE);
> >>>> + record_full_next_insn = 0;
> >>>> + }
> >>>> + else if (record_full_next_insn > record_full_list.size ())
> >>>> + {
> >>>> + gdb_assert (execution_direction == EXEC_FORWARD);
> >>>> + record_full_next_insn = record_full_list.size ();
> >>>> + }
> >>>> + /* Reset the current instruciton to point to the one to be replayed
> >>> Nit: instruction
> >>>
> >>>> + moving forward. */
> >>>> + else if (execution_direction == EXEC_REVERSE)
> >>>> + record_full_next_insn++;
> >>>> +
> >>>> replay_out:
> >>>> if (status->kind () == TARGET_WAITKIND_STOPPED)
> >>>> {
> >>>> + int insn = (execution_direction == EXEC_FORWARD)
> >>>> + ? record_full_next_insn - 1 : record_full_next_insn;
> >>>> if (record_full_get_sig)
> >>>> status->set_stopped (GDB_SIGNAL_INT);
> >>>> - else if (record_full_list->u.end.sigval != GDB_SIGNAL_0)
> >>>> - /* FIXME: better way to check */
> >>>> - status->set_stopped (record_full_list->u.end.sigval);
> >>>> + else if (record_full_list[insn].sigval.has_value ())
> >>>> + status->set_stopped
> >>>> + (record_full_list[insn].sigval.value ());
> >>>> else
> >>>> status->set_stopped (GDB_SIGNAL_TRAP);
> >>>> }
> >>>> @@ -1464,12 +1346,9 @@ record_full_wait_1 (struct target_ops *ops,
> >>>> catch (const gdb_exception &ex)
> >>>> {
> >>>> if (execution_direction == EXEC_REVERSE)
> >>>> - {
> >>>> - if (record_full_list->next)
> >>>> - record_full_list = record_full_list->next;
> >>>> - }
> >>>> + record_full_next_insn++;
> >>>> else
> >>>> - record_full_list = record_full_list->prev;
> >>>> + record_full_next_insn--;
> >>>>
> >>>> throw;
> >>>> }
> >>>> @@ -1557,8 +1436,7 @@ record_full_registers_change (struct
> regcache
> >>>> *regcache, int regnum)
> >>>> /* Check record_full_insn_num. */
> >>>> record_full_check_insn_num ();
> >>>>
> >>>> - record_full_arch_list_head = NULL;
> >>>> - record_full_arch_list_tail = NULL;
> >>>> + record_full_reset_incomplete ();
> >>>>
> >>>> if (regnum < 0)
> >>>> {
> >>>> @@ -1568,7 +1446,7 @@ record_full_registers_change (struct
> regcache
> >>>> *regcache, int regnum)
> >>>> {
> >>>> if (record_full_arch_list_add_reg (regcache, i))
> >>>> {
> >>>> - record_full_list_release (record_full_arch_list_tail);
> >>>> + record_full_reset_incomplete ();
> >>>> error (_("Process record: failed to record execution log."));
> >>>> }
> >>>> }
> >>>> @@ -1577,18 +1455,11 @@ record_full_registers_change (struct
> >> regcache
> >>>> *regcache, int regnum)
> >>>> {
> >>>> if (record_full_arch_list_add_reg (regcache, regnum))
> >>>> {
> >>>> - record_full_list_release (record_full_arch_list_tail);
> >>>> + record_full_reset_incomplete ();
> >>>> error (_("Process record: failed to record execution log."));
> >>>> }
> >>>> }
> >>>> - if (record_full_arch_list_add_end ())
> >>>> - {
> >>>> - record_full_list_release (record_full_arch_list_tail);
> >>>> - error (_("Process record: failed to record execution log."));
> >>>> - }
> >>>> - record_full_list->next = record_full_arch_list_head;
> >>>> - record_full_arch_list_head->prev = record_full_list;
> >>>> - record_full_list = record_full_arch_list_tail;
> >>>> + record_full_save_instruction ();
> >>>>
> >>>> if (record_full_insn_num == record_full_insn_max_num)
> >>>> record_full_list_release_first ();
> >>>> @@ -1607,7 +1478,7 @@ record_full_target::store_registers (struct
> >>>> regcache *regcache, int regno)
> >>>> {
> >>>> int n;
> >>>>
> >>>> - /* Let user choose if he wants to write register or not. */
> >>>> + /* Let user choose if they want to write register or not. */
> >>>> if (regno < 0)
> >>>> n =
> >>>> query (_("Because GDB is in replay mode, changing the "
> >>>> @@ -1642,7 +1513,7 @@ record_full_target::store_registers (struct
> >>>> regcache *regcache, int regno)
> >>>> }
> >>>>
> >>>> /* Destroy the record from here forward. */
> >>>> - record_full_list_release_following (record_full_list);
> >>>> + record_full_list_release_following (record_full_next_insn);
> >>>> }
> >>>>
> >>>> record_full_registers_change (regcache, regno);
> >>>> @@ -1675,36 +1546,24 @@ record_full_target::xfer_partial (enum
> >>>> target_object object,
> >>>> error (_("Process record canceled the operation."));
> >>>>
> >>>> /* Destroy the record from here forward. */
> >>>> - record_full_list_release_following (record_full_list);
> >>>> + record_full_list_release_following (record_full_next_insn);
> >>>> }
> >>>>
> >>>> /* Check record_full_insn_num */
> >>>> record_full_check_insn_num ();
> >>>>
> >>>> /* Record registers change to list as an instruction. */
> >>>> - record_full_arch_list_head = NULL;
> >>>> - record_full_arch_list_tail = NULL;
> >>>> + record_full_reset_incomplete ();
> >>>> if (record_full_arch_list_add_mem (offset, len))
> >>>> {
> >>>> - record_full_list_release (record_full_arch_list_tail);
> >>>> + record_full_reset_incomplete ();
> >>>> if (record_debug)
> >>>> gdb_printf (gdb_stdlog,
> >>>> "Process record: failed to record "
> >>>> "execution log.");
> >>>> return TARGET_XFER_E_IO;
> >>>> }
> >>>> - if (record_full_arch_list_add_end ())
> >>>> - {
> >>>> - record_full_list_release (record_full_arch_list_tail);
> >>>> - if (record_debug)
> >>>> - gdb_printf (gdb_stdlog,
> >>>> - "Process record: failed to record "
> >>>> - "execution log.");
> >>>> - return TARGET_XFER_E_IO;
> >>>> - }
> >>>> - record_full_list->next = record_full_arch_list_head;
> >>>> - record_full_arch_list_head->prev = record_full_list;
> >>>> - record_full_list = record_full_arch_list_tail;
> >>>> + record_full_save_instruction ();
> >>>>
> >>>> if (record_full_insn_num == record_full_insn_max_num)
> >>>> record_full_list_release_first ();
> >>>> @@ -1866,8 +1725,7 @@ record_full_base_target::get_bookmark
> (const
> >> char
> >>>> *args, int from_tty)
> >>>> char *ret = NULL;
> >>>>
> >>>> /* Return stringified form of instruction count. */
> >>>> - if (record_full_list && record_full_list->type == record_full_end)
> >>>> - ret = xstrdup (pulongest (record_full_list->u.end.insn_num));
> >>>> + ret = xstrdup (pulongest
> >> (record_full_list[record_full_next_insn].insn_num));
> >>> I think we can get here with an empty record_full_list - in case we are in
> >> recording mode,
> >>> no instructions have been logged and this function is called:
> >>>
> >>> ~~~
> >>> (gdb) info record
> >>> Active record target: record-full
> >>> Record mode:
> >>> No instructions have been logged.
> >>> Max logged instructions is 200000.
> >>> (gdb) bookmark
> >>>
> >>> Thread 1 "gdb-up" hit Breakpoint 1,
> record_full_base_target::get_bookmark
> >> (this=0x555558392900 <record_full_ops>, args=0x0, from_tty=1) at
> >> /tmp/record-full.c:1774
> >>> 1774 char *ret = NULL;
> >>> (gdb) p record_full_next_insn
> >>> $1 = 0
> >>> (gdb) p record_full_list.empty ()
> >>> $2 = true
> >>> ~~~
> > I wonder, do we somewhere have a test for bookmarks?
> > I also find a specific description for this in the manual... what's the
> difference to checkpoints?
>
> Checkpoints fork the inferior and stop the fork immediately, allowing
> you to go back to that one point in time, but not executing backwards or
> anything, just changing forks and letting you see what things were like
> back then (that's why they won't work with multi-threaded programs).
> entirely unrelated to reverse debugging
>
> Bookmarks let you mark one instruction in the history and easily go back
> to it using the reverse mechanism... at least that's what I've been able
> to get from the code, this predates me and I have no idea how it is
> actually used....
>
> I quickly grep'd for bookmark tests and couldn't find any. We should
> probably add them at some point, if anyone even uses that feature......
Or at least adding some documentation, maybe more people would use it then ... 😉
Otherwise, if nobody uses it, we could deprecate and remove it at some point?
It just adds even more code to maintain...
> >
> > I am a bit confused about the bookmark feature (of course, this is nothing
> to fix for this series...).
> >
> >>>> if (record_debug)
> >>>> {
> >>>> @@ -1923,30 +1781,22 @@ record_full_base_target::record_method
> >> (ptid_t
> >>>> ptid)
> >>>> void
> >>>> record_full_base_target::info_record ()
> >>>> {
> >>>> - struct record_full_entry *p;
> >>>> -
> >>>> if (RECORD_FULL_IS_REPLAY)
> >>>> gdb_printf (_("Replay mode:\n"));
> >>>> else
> >>>> gdb_printf (_("Record mode:\n"));
> >>>>
> >>>> - /* Find entry for first actual instruction in the log. */
> >>>> - for (p = record_full_first.next;
> >>>> - p != NULL && p->type != record_full_end;
> >>>> - p = p->next)
> >>>> - ;
> >>>> -
> >>>> /* Do we have a log at all? */
> >>>> - if (p != NULL && p->type == record_full_end)
> >>>> + if (!record_full_list.empty ())
> >>>> {
> >>>> /* Display instruction number for first instruction in the log. */
> >>>> - gdb_printf (_("Lowest recorded instruction number is %s.\n"),
> >>>> - pulongest (p->u.end.insn_num));
> >>>> + gdb_printf (_("Lowest recorded instruction number is %u.\n"),
> >>>> + record_full_list[0].insn_num);
> >>>>
> >>>> /* If in replay mode, display where we are in the log. */
> >>>> if (RECORD_FULL_IS_REPLAY)
> >>>> - gdb_printf (_("Current instruction number is %s.\n"),
> >>>> - pulongest (record_full_list->u.end.insn_num));
> >>>> + gdb_printf (_("Current instruction number is %u.\n"),
> >>>> + record_full_list[record_full_next_insn].insn_num);
> >>>>
> >>>> /* Display instruction number for last instruction in the log. */
> >>>> gdb_printf (_("Highest recorded instruction number is %s.\n"),
> >>>> @@ -1975,7 +1825,7 @@
> >> record_full_base_target::supports_delete_record ()
> >>>> void
> >>>> record_full_base_target::delete_record ()
> >>>> {
> >>>> - record_full_list_release_following (record_full_list);
> >>>> + record_full_reset_history ();
> >>>> }
> >>>>
> >>>> /* The "record_is_replaying" target method. */
> >>>> @@ -2001,23 +1851,23 @@
> record_full_base_target::record_will_replay
> >>>> (ptid_t ptid, int dir)
> >>>> /* Go to a specific entry. */
> >>>>
> >>>> static void
> >>>> -record_full_goto_entry (struct record_full_entry *p)
> >>>> +record_full_goto_entry (size_t target_insn)
> >>>> {
> >>>> - if (p == NULL)
> >>>> + if (target_insn >= record_full_list.size ())
> >>>> error (_("Target insn not found."));
> >>>> - else if (p == record_full_list)
> >>>> + else if (target_insn == record_full_next_insn)
> >>>> error (_("Already at target insn."));
> >>>> - else if (p->u.end.insn_num > record_full_list->u.end.insn_num)
> >>>> + else if (target_insn > record_full_next_insn)
> >>>> {
> >>>> gdb_printf (_("Go forward to insn number %s\n"),
> >>>> - pulongest (p->u.end.insn_num));
> >>>> - record_full_goto_insn (p, EXEC_FORWARD);
> >>>> + pulongest (record_full_list[target_insn].insn_num));
> >>>> + record_full_goto_insn (target_insn, EXEC_FORWARD);
> >>>> }
> >>>> else
> >>>> {
> >>>> gdb_printf (_("Go backward to insn number %s\n"),
> >>>> - pulongest (p->u.end.insn_num));
> >>>> - record_full_goto_insn (p, EXEC_REVERSE);
> >>>> + pulongest (target_insn));
> >>>> + record_full_goto_insn (target_insn, EXEC_REVERSE);
> >>>> }
> >>>>
> >>>> registers_changed ();
> >>>> @@ -2033,13 +1883,7 @@ record_full_goto_entry (struct
> >> record_full_entry
> >>>> *p)
> >>>> void
> >>>> record_full_base_target::goto_record_begin ()
> >>>> {
> >>>> - struct record_full_entry *p = NULL;
> >>>> -
> >>>> - for (p = &record_full_first; p != NULL; p = p->next)
> >>>> - if (p->type == record_full_end)
> >>>> - break;
> >>>> -
> >>>> - record_full_goto_entry (p);
> >>>> + record_full_goto_entry (0);
> >>>> }
> >>>>
> >>>> /* The "goto_record_end" target method. */
> >>>> @@ -2047,15 +1891,7 @@
> record_full_base_target::goto_record_begin ()
> >>>> void
> >>>> record_full_base_target::goto_record_end ()
> >>>> {
> >>>> - struct record_full_entry *p = NULL;
> >>>> -
> >>>> - for (p = record_full_list; p->next != NULL; p = p->next)
> >>>> - ;
> >>>> - for (; p!= NULL; p = p->prev)
> >>>> - if (p->type == record_full_end)
> >>>> - break;
> >>>> -
> >>>> - record_full_goto_entry (p);
> >>>> + record_full_goto_entry (record_full_list.size () -1);
> >>> Nit: whitespace before 1 => "record_full_list.size () - 1"
> >>>
> >>> And in case the record_full_list is empty, won't we call
> >>> record_full_goto_entry with an invalid value for target_insn ?
> >>>
> >>>> }
> >>>>
> >>>> /* The "goto_record" target method. */
> >>>> @@ -2063,13 +1899,7 @@ record_full_base_target::goto_record_end
> ()
> >>>> void
> >>>> record_full_base_target::goto_record (ULONGEST target_insn)
> >>>> {
> >>>> - struct record_full_entry *p = NULL;
> >>>> -
> >>>> - for (p = &record_full_first; p != NULL; p = p->next)
> >>>> - if (p->type == record_full_end && p->u.end.insn_num == target_insn)
> >>>> - break;
> >>>> -
> >>>> - record_full_goto_entry (p);
> >>>> + record_full_goto_entry (target_insn);
> >>>> }
> >>>>
> >>>> /* The "record_stop_replaying" target method. */
> >>>> @@ -2339,19 +2169,96 @@ netorder32 (uint32_t input)
> >>>> return ret;
> >>>> }
> >>>>
> >>>> +static void
> >>>> +record_full_read_entry_from_bfd (bfd *cbfd, asection *osec, int
> >> *bfd_offset)
> >>>> +{
> >>>> + uint8_t rectype;
> >>>> + uint32_t regnum, len;
> >>>> + uint64_t addr;
> >>>> + regcache *cache = get_thread_regcache (inferior_thread ());
> >>>> +
> >>>> + bfdcore_read (cbfd, osec, &rectype, sizeof (rectype), bfd_offset);
> >>>> + switch (rectype)
> >>>> + {
> >>>> + case record_full_reg: /* reg */
> >>>> + {
> >>>> + /* Get register number to regnum. */
> >>>> + bfdcore_read (cbfd, osec, ®num, sizeof (regnum), bfd_offset);
> >>>> + regnum = netorder32 (regnum);
> >>>> +
> >>>> + record_full_entry rec;
> >>>> +
> >>>> + rec = record_full_reg_init (cache, regnum);
> >>>> +
> >>>> + /* Get val. */
> >>>> + bfdcore_read (cbfd, osec, record_full_get_loc (&rec),
> >>>> + rec.u.reg.len, bfd_offset);
> >>>> +
> >>>> + if (record_debug)
> >>>> + gdb_printf (gdb_stdlog,
> >>>> + " Reading register %d (1 "
> >>>> + "plus %lu plus %d bytes)\n",
> >>>> + rec.u.reg.num,
> >>>> + (unsigned long) sizeof (regnum),
> >>>> + rec.u.reg.len);
> >>>> +
> >>>> + record_full_arch_list_add (rec);
> >>>> + break;
> >>>> + }
> >>>> +
> >>>> + case record_full_mem: /* mem */
> >>>> + {
> >>>> + /* Get len. */
> >>>> + bfdcore_read (cbfd, osec, &len, sizeof (len), bfd_offset);
> >>>> + len = netorder32 (len);
> >>>> +
> >>>> + /* Get addr. */
> >>>> + bfdcore_read (cbfd, osec, &addr, sizeof (addr),
> >>>> + bfd_offset);
> >>>> + addr = netorder64 (addr);
> >>>> +
> >>>> + record_full_entry rec;
> >>>> + rec = record_full_mem_init (addr, len);
> >>>> +
> >>>> + /* Get val. */
> >>>> + bfdcore_read (cbfd, osec, record_full_get_loc (&rec), len,
> >>>> + bfd_offset);
> >>>> +
> >>>> + if (record_debug)
> >>>> + gdb_printf (gdb_stdlog,
> >>>> + " Reading memory %s (1 plus "
> >>>> + "%lu plus %lu plus %d bytes)\n",
> >>>> + paddress (get_current_arch (),
> >>>> + rec.u.mem.addr),
> >>>> + (unsigned long) sizeof (addr),
> >>>> + (unsigned long) sizeof (len),
> >>>> + len);
> >>>> +
> >>>> + record_full_arch_list_add (rec);
> >>>> + break;
> >>>> + }
> >>>> +
> >>>> + default:
> >>>> + error (_("Bad entry type %d, offset %d of %lu in core file %ps."),
> >>>> + rectype, *bfd_offset, bfd_section_size (osec),
> >>>> + styled_string (file_name_style.style (),
> >>>> + bfd_get_filename (cbfd)));
> >>>> + break;
> >>>> + }
> >>>> +}
> >>>> +
> >>>> /* Restore the execution log from core file CBFD. */
> >>>>
> >>>> static void
> >>>> record_full_restore (struct bfd &cbfd)
> >>>> {
> >>>> uint32_t magic;
> >>>> - struct record_full_entry *rec;
> >>>> asection *osec;
> >>>> uint32_t osec_size;
> >>>> int bfd_offset = 0;
> >>>>
> >>>> /* "record_full_restore" can only be called when record list is empty.
> */
> >>>> - gdb_assert (record_full_first.next == NULL);
> >>>> + gdb_assert (record_full_list.empty ());
> >>>>
> >>>> if (record_debug)
> >>>> gdb_printf (gdb_stdlog, "Restoring recording from core file.\n");
> >>>> @@ -2379,124 +2286,47 @@ record_full_restore (struct bfd &cbfd)
> >>>> "RECORD_FULL_FILE_MAGIC (0x%s)\n",
> >>>> phex_nz (netorder32 (magic), 4));
> >>>>
> >>>> - /* Restore the entries in recfd into record_full_arch_list_head and
> >>>> - record_full_arch_list_tail. */
> >>>> - record_full_arch_list_head = NULL;
> >>>> - record_full_arch_list_tail = NULL;
> >>>> record_full_insn_num = 0;
> >>>>
> >>>> try
> >>>> {
> >>>> - regcache *regcache = get_thread_regcache (inferior_thread ());
> >>>> -
> >>>> - while (1)
> >>>> + while (bfd_offset < osec_size)
> >>>> {
> >>>> - uint8_t rectype;
> >>>> - uint32_t regnum, len, signal, count;
> >>>> - uint64_t addr;
> >>>> -
> >>>> - /* We are finished when offset reaches osec_size. */
> >>>> - if (bfd_offset >= osec_size)
> >>>> - break;
> >>>> - bfdcore_read (&cbfd, osec, &rectype, sizeof (rectype), &bfd_offset);
> >>>> -
> >>>> - switch (rectype)
> >>>> + record_full_reset_incomplete ();
> >>>> + uint32_t eff_count = 0;
> >>>> + uint8_t sigval;
> >>>> + uint32_t insn_num;
> >>>> +
> >>>> + /* First read the generic information for an instruction. */
> >>>> + bfdcore_read (&cbfd, osec, &sigval, sizeof (uint8_t), &bfd_offset);
> >>>> + bfdcore_read (&cbfd, osec, &eff_count, sizeof (uint32_t),
> >>>> + &bfd_offset);
> >>>> + bfdcore_read (&cbfd, osec, &insn_num, sizeof (uint32_t),
> >>>> + &bfd_offset);
> >>>> +
> >>>> + record_full_incomplete_instruction.insn_num = netorder32
> >>>> (insn_num);
> >>>> + if (sigval != GDB_SIGNAL_0)
> >>>> + record_full_incomplete_instruction.sigval = (gdb_signal) sigval;
> >>>> +
> >>>> + eff_count = netorder32 (eff_count);
> >>>> +
> >>>> + /* This deals with all the side effects. */
> >>>> + while (eff_count > 0)
> >>>> {
> >>> There is one space too much indent.
> >>>
> >>>> - case record_full_reg: /* reg */
> >>>> - /* Get register number to regnum. */
> >>>> - bfdcore_read (&cbfd, osec, ®num, sizeof (regnum),
> >>>> - &bfd_offset);
> >>>> - regnum = netorder32 (regnum);
> >>>> -
> >>>> - rec = record_full_reg_alloc (regcache, regnum);
> >>>> -
> >>>> - /* Get val. */
> >>>> - bfdcore_read (&cbfd, osec, record_full_get_loc (rec),
> >>>> - rec->u.reg.len, &bfd_offset);
> >>>> -
> >>>> - if (record_debug)
> >>>> - gdb_printf (gdb_stdlog,
> >>>> - " Reading register %d (1 "
> >>>> - "plus %lu plus %d bytes)\n",
> >>>> - rec->u.reg.num,
> >>>> - (unsigned long) sizeof (regnum),
> >>>> - rec->u.reg.len);
> >>>> - break;
> >>>> + eff_count--;
> >>>>
> >>>> - case record_full_mem: /* mem */
> >>>> - /* Get len. */
> >>>> - bfdcore_read (&cbfd, osec, &len, sizeof (len), &bfd_offset);
> >>>> - len = netorder32 (len);
> >>>> -
> >>>> - /* Get addr. */
> >>>> - bfdcore_read (&cbfd, osec, &addr, sizeof (addr), &bfd_offset);
> >>>> - addr = netorder64 (addr);
> >>>> -
> >>>> - rec = record_full_mem_alloc (addr, len);
> >>>> -
> >>>> - /* Get val. */
> >>>> - bfdcore_read (&cbfd, osec, record_full_get_loc (rec),
> >>>> - rec->u.mem.len, &bfd_offset);
> >>>> -
> >>>> - if (record_debug)
> >>>> - gdb_printf (gdb_stdlog,
> >>>> - " Reading memory %s (1 plus "
> >>>> - "%lu plus %lu plus %d bytes)\n",
> >>>> - paddress (get_current_arch (),
> >>>> - rec->u.mem.addr),
> >>>> - (unsigned long) sizeof (addr),
> >>>> - (unsigned long) sizeof (len),
> >>>> - rec->u.mem.len);
> >>>> - break;
> >>>> -
> >>>> - case record_full_end: /* end */
> >>>> - rec = record_full_end_alloc ();
> >>>> - record_full_insn_num ++;
> >>>> -
> >>>> - /* Get signal value. */
> >>>> - bfdcore_read (&cbfd, osec, &signal, sizeof (signal),
> >>>> - &bfd_offset);
> >>>> - signal = netorder32 (signal);
> >>>> - rec->u.end.sigval = (enum gdb_signal) signal;
> >>>> -
> >>>> - /* Get insn count. */
> >>>> - bfdcore_read (&cbfd, osec, &count, sizeof (count), &bfd_offset);
> >>>> - count = netorder32 (count);
> >>>> - rec->u.end.insn_num = count;
> >>>> - record_full_insn_count = count + 1;
> >>>> - if (record_debug)
> >>>> - gdb_printf (gdb_stdlog,
> >>>> - " Reading record_full_end (1 + "
> >>>> - "%lu + %lu bytes), offset == %s\n",
> >>>> - (unsigned long) sizeof (signal),
> >>>> - (unsigned long) sizeof (count),
> >>>> - paddress (get_current_arch (),
> >>>> - bfd_offset));
> >>>> - break;
> >>>> -
> >>>> - default:
> >>>> - error (_("Bad entry type in core file %ps."),
> >>>> - styled_string (file_name_style.style (),
> >>>> - bfd_get_filename (&cbfd)));
> >>>> - break;
> >>>> + record_full_read_entry_from_bfd (&cbfd, osec, &bfd_offset);
> >>>> }
> >>>>
> >>>> - /* Add rec to record arch list. */
> >>>> - record_full_arch_list_add (rec);
> >>>> + record_full_save_instruction ();
> >>>> }
> >>>> }
> >>>> catch (const gdb_exception &ex)
> >>>> {
> >>>> - record_full_list_release (record_full_arch_list_tail);
> >>>> + record_full_reset_incomplete ();
> >>>> throw;
> >>>> }
> >>>>
> >>>> - /* Add record_full_arch_list_head to the end of record list. */
> >>>> - record_full_first.next = record_full_arch_list_head;
> >>>> - record_full_arch_list_head->prev = &record_full_first;
> >>>> - record_full_arch_list_tail->next = NULL;
> >>>> - record_full_list = &record_full_first;
> >>>> -
> >>>> /* Update record_full_insn_max_num. */
> >>>> if (record_full_insn_num > record_full_insn_max_num)
> >>>> {
> >>>> @@ -2505,6 +2335,10 @@ record_full_restore (struct bfd &cbfd)
> >>>> record_full_insn_max_num);
> >>>> }
> >>>>
> >>>> + /* When loading a recording, we'll always start at the oldest possible
> >>>> + instruction, no matter where the original recording was stopped. */
> >>>> + record_full_next_insn = 0;
> >>>> +
> >>>> /* Succeeded. */
> >>>> gdb_printf (_("Restored records from core file %s.\n"),
> >>>> bfd_get_filename (&cbfd));
> >>>> @@ -2538,13 +2372,73 @@ cmd_record_full_restore (const char
> *args,
> >> int
> >>>> from_tty)
> >>>> record_full_open (nullptr, from_tty);
> >>>> }
> >>>>
> >>>> +static void
> >>>> +record_full_write_entry_to_bfd (record_full_entry &entry,
> >>>> + gdb_bfd_ref_ptr obfd,
> >>>> + asection *osec, int *bfd_offset,
> >>>> + struct gdbarch *gdbarch)
> >>>> +{
> >>>> + /* Save entry. */
> >>>> + uint8_t type;
> >>>> + uint32_t regnum, len;
> >>>> + uint64_t addr;
> >>>> +
> >>>> + type = entry.type;
> >>>> + bfdcore_write (obfd.get (), osec, &type, sizeof (type), bfd_offset);
> >>>> +
> >>>> + switch (entry.type)
> >>>> + {
> >>>> + case record_full_reg: /* reg */
> >>>> + if (record_debug)
> >>>> + gdb_printf (gdb_stdlog,
> >>>> + " Writing register %d (1 "
> >>>> + "plus %lu plus %d bytes)\n",
> >>>> + entry.u.reg.num,
> >>>> + (unsigned long) sizeof (regnum),
> >>>> + entry.u.reg.len);
> >>>> +
> >>>> + /* Write regnum. */
> >>>> + regnum = netorder32 (entry.u.reg.num);
> >>>> + bfdcore_write (obfd.get (), osec, ®num, sizeof (regnum),
> >> bfd_offset);
> >>>> +
> >>>> + /* Write regval. */
> >>>> + bfdcore_write (obfd.get (), osec, record_full_get_loc (&entry),
> >>>> + entry.u.reg.len, bfd_offset);
> >>>> + break;
> >>>> +
> >>>> + case record_full_mem: /* mem */
> >>>> + if (record_debug)
> >>>> + gdb_printf (gdb_stdlog,
> >>>> + " Writing memory %s (1 plus "
> >>>> + "%lu plus %lu plus %d bytes)\n",
> >>>> + paddress (gdbarch,
> >>>> + entry.u.mem.addr),
> >>>> + (unsigned long) sizeof (addr),
> >>>> + (unsigned long) sizeof (len),
> >>>> + entry.u.mem.len);
> >>>> +
> >>>> + /* Write memlen. */
> >>>> + len = netorder32 (entry.u.mem.len);
> >>>> + bfdcore_write (obfd.get (), osec, &len, sizeof (len), bfd_offset);
> >>>> +
> >>>> + /* Write memaddr. */
> >>>> + addr = netorder64 (entry.u.mem.addr);
> >>>> + bfdcore_write (obfd.get (), osec, &addr, sizeof (addr), bfd_offset);
> >>>> +
> >>>> + /* Write memval. */
> >>>> + bfdcore_write (obfd.get (), osec, record_full_get_loc (&entry),
> >>>> + entry.u.mem.len, bfd_offset);
> >>>> + break;
> >>>> + }
> >>>> +
> >>>> +}
> >>>> +
> >>>> /* Save the execution log to a file. We use a modified elf corefile
> >>>> format, with an extra section for our data. */
> >>>>
> >>>> void
> >>>> record_full_base_target::save_record (const char *recfilename)
> >>>> {
> >>>> - struct record_full_entry *cur_record_full_list;
> >>>> uint32_t magic;
> >>>> struct gdbarch *gdbarch;
> >>>> int save_size = 0;
> >>>> @@ -2562,9 +2456,6 @@ record_full_base_target::save_record (const
> >> char
> >>>> *recfilename)
> >>>> /* Arrange to remove the output file on failure. */
> >>>> gdb::unlinker unlink_file (recfilename);
> >>>>
> >>>> - /* Save the current record entry to "cur_record_full_list". */
> >>>> - cur_record_full_list = record_full_list;
> >>>> -
> >>>> /* Get the values of regcache and gdbarch. */
> >>>> regcache *regcache = get_thread_regcache (inferior_thread ());
> >>>> gdbarch = regcache->arch ();
> >>>> @@ -2574,34 +2465,27 @@ record_full_base_target::save_record
> (const
> >>>> char *recfilename)
> >>>> = record_full_gdb_operation_disable_set ();
> >>>>
> >>>> /* Reverse execute to the begin of record list. */
> >>>> - while (1)
> >>>> - {
> >>>> - /* Check for beginning and end of log. */
> >>>> - if (record_full_list == &record_full_first)
> >>>> - break;
> >>>> -
> >>>> - record_full_exec_insn (regcache, gdbarch, record_full_list);
> >>>> -
> >>>> - if (record_full_list->prev)
> >>>> - record_full_list = record_full_list->prev;
> >>>> - }
> >>>> + for (int i = record_full_next_insn - 1; i >= 0; i--)
> >>>> + record_full_exec_insn (regcache, gdbarch,
> >>>> + record_full_list[i]);
> >>>>
> >>>> /* Compute the size needed for the extra bfd section. */
> >>>> save_size = 4; /* magic cookie */
> >>>> - for (record_full_list = record_full_first.next; record_full_list;
> >>>> - record_full_list = record_full_list->next)
> >>>> - switch (record_full_list->type)
> >>>> - {
> >>>> - case record_full_end:
> >>>> - save_size += 1 + 4 + 4;
> >>>> - break;
> >>>> - case record_full_reg:
> >>>> - save_size += 1 + 4 + record_full_list->u.reg.len;
> >>>> - break;
> >>>> - case record_full_mem:
> >>>> - save_size += 1 + 4 + 8 + record_full_list->u.mem.len;
> >>>> - break;
> >>>> - }
> >>>> + for (int i = record_full_list.size () - 1; i >= 0; i--)
> >>>> + {
> >>>> + /* Number of effects of an instruction. */
> >>>> + save_size += sizeof (uint32_t) + sizeof (uint8_t) + sizeof (uint32_t);
> >>>> + for (auto &entry : record_full_list[i].effects)
> >>>> + switch (entry.type)
> >>>> + {
> >>>> + case record_full_reg:
> >>>> + save_size += 1 + 4 + entry.u.reg.len;
> >>>> + break;
> >>>> + case record_full_mem:
> >>>> + save_size += 1 + 4 + 8 + entry.u.mem.len;
> >>>> + break;
> >>>> + }
> >>>> + }
> >>>>
> >>>> /* Make the new bfd section. */
> >>>> osec = bfd_make_section_anyway_with_flags (obfd.get (), "precord",
> >>>> @@ -2630,108 +2514,32 @@ record_full_base_target::save_record
> >> (const
> >>>> char *recfilename)
> >>>>
> >>>> /* Save the entries to recfd and forward execute to the end of
> >>>> record list. */
> >>>> - record_full_list = &record_full_first;
> >>>> - while (1)
> >>>> + for (int i = 0; i < record_full_list.size (); i++)
> >>>> {
> >>>> - /* Save entry. */
> >>>> - if (record_full_list != &record_full_first)
> >>>> + uint32_t eff_count = (uint32_t) record_full_list[i].effects.size ();
> >>>> + uint32_t insn_num = record_full_list[i].insn_num;
> >>>> + uint8_t sigval = (record_full_list[i].sigval.has_value ())
> >>>> + ? record_full_list[i].sigval.value ()
> >>>> + : GDB_SIGNAL_0;
> >>>> +
> >>>> + /* Signal. */
> >>>> + bfdcore_write (obfd.get (), osec, &sigval, sizeof (sigval),
> &bfd_offset);
> >>>> + eff_count = netorder32 (eff_count);
> >>>> + /* Number of effects. */
> >>>> + bfdcore_write (obfd.get (), osec, &eff_count, sizeof (eff_count),
> >>>> + &bfd_offset);
> >>>> + /* Instruction number. */
> >>>> + bfdcore_write (obfd.get (), osec, &insn_num, sizeof (uint32_t),
> >>>> + &bfd_offset);
> >>>> +
> >>>> + for (auto &entry : record_full_list[i].effects)
> >>>> {
> >>>> - uint8_t type;
> >>>> - uint32_t regnum, len, signal, count;
> >>>> - uint64_t addr;
> >>>> -
> >>>> - type = record_full_list->type;
> >>>> - bfdcore_write (obfd.get (), osec, &type, sizeof (type), &bfd_offset);
> >>>> -
> >>>> - switch (record_full_list->type)
> >>>> - {
> >>>> - case record_full_reg: /* reg */
> >>>> - if (record_debug)
> >>>> - gdb_printf (gdb_stdlog,
> >>>> - " Writing register %d (1 "
> >>>> - "plus %lu plus %d bytes)\n",
> >>>> - record_full_list->u.reg.num,
> >>>> - (unsigned long) sizeof (regnum),
> >>>> - record_full_list->u.reg.len);
> >>>> -
> >>>> - /* Write regnum. */
> >>>> - regnum = netorder32 (record_full_list->u.reg.num);
> >>>> - bfdcore_write (obfd.get (), osec, ®num,
> >>>> - sizeof (regnum), &bfd_offset);
> >>>> -
> >>>> - /* Write regval. */
> >>>> - bfdcore_write (obfd.get (), osec,
> >>>> - record_full_get_loc (record_full_list),
> >>>> - record_full_list->u.reg.len, &bfd_offset);
> >>>> - break;
> >>>> -
> >>>> - case record_full_mem: /* mem */
> >>>> - if (record_debug)
> >>>> - gdb_printf (gdb_stdlog,
> >>>> - " Writing memory %s (1 plus "
> >>>> - "%lu plus %lu plus %d bytes)\n",
> >>>> - paddress (gdbarch,
> >>>> - record_full_list->u.mem.addr),
> >>>> - (unsigned long) sizeof (addr),
> >>>> - (unsigned long) sizeof (len),
> >>>> - record_full_list->u.mem.len);
> >>>> -
> >>>> - /* Write memlen. */
> >>>> - len = netorder32 (record_full_list->u.mem.len);
> >>>> - bfdcore_write (obfd.get (), osec, &len, sizeof (len),
> >>>> - &bfd_offset);
> >>>> -
> >>>> - /* Write memaddr. */
> >>>> - addr = netorder64 (record_full_list->u.mem.addr);
> >>>> - bfdcore_write (obfd.get (), osec, &addr,
> >>>> - sizeof (addr), &bfd_offset);
> >>>> -
> >>>> - /* Write memval. */
> >>>> - bfdcore_write (obfd.get (), osec,
> >>>> - record_full_get_loc (record_full_list),
> >>>> - record_full_list->u.mem.len, &bfd_offset);
> >>>> - break;
> >>>> -
> >>>> - case record_full_end:
> >>>> - if (record_debug)
> >>>> - gdb_printf (gdb_stdlog,
> >>>> - " Writing record_full_end (1 + "
> >>>> - "%lu + %lu bytes)\n",
> >>>> - (unsigned long) sizeof (signal),
> >>>> - (unsigned long) sizeof (count));
> >>>> - /* Write signal value. */
> >>>> - signal = netorder32 (record_full_list->u.end.sigval);
> >>>> - bfdcore_write (obfd.get (), osec, &signal,
> >>>> - sizeof (signal), &bfd_offset);
> >>>> -
> >>>> - /* Write insn count. */
> >>>> - count = netorder32 (record_full_list->u.end.insn_num);
> >>>> - bfdcore_write (obfd.get (), osec, &count,
> >>>> - sizeof (count), &bfd_offset);
> >>>> - break;
> >>>> - }
> >>>> + record_full_write_entry_to_bfd (entry, obfd, osec, &bfd_offset,
> >>>> + gdbarch);
> >>>> }
> >>>> -
> >>>> /* Execute entry. */
> >>>> - record_full_exec_insn (regcache, gdbarch, record_full_list);
> >>>> -
> >>>> - if (record_full_list->next)
> >>>> - record_full_list = record_full_list->next;
> >>>> - else
> >>>> - break;
> >>>> - }
> >>>> -
> >>>> - /* Reverse execute to cur_record_full_list. */
> >>>> - while (1)
> >>>> - {
> >>>> - /* Check for beginning and end of log. */
> >>>> - if (record_full_list == cur_record_full_list)
> >>>> - break;
> >>>> -
> >>>> - record_full_exec_insn (regcache, gdbarch, record_full_list);
> >>>> -
> >>>> - if (record_full_list->prev)
> >>>> - record_full_list = record_full_list->prev;
> >>>> + if (i < record_full_next_insn)
> >>>> + record_full_exec_insn (regcache, gdbarch, record_full_list[i]);
> >>>> }
> >>>>
> >>>> unlink_file.keep ();
> >>>> @@ -2746,7 +2554,7 @@ record_full_base_target::save_record (const
> >> char
> >>>> *recfilename)
> >>>> correspondingly. */
> >>>>
> >>>> static void
> >>>> -record_full_goto_insn (struct record_full_entry *entry,
> >>>> +record_full_goto_insn (size_t target_insn,
> >>>> enum exec_direction_kind dir)
> >>> You could explain the new parameter in the function description.
> >>>
> >>>> {
> >>>> scoped_restore restore_operation_disable
> >>>> @@ -2757,17 +2565,12 @@ record_full_goto_insn (struct
> >> record_full_entry
> >>>> *entry,
> >>>> /* Assume everything is valid: we will hit the entry,
> >>>> and we will not hit the end of the recording. */
> >>>>
> >>>> - if (dir == EXEC_FORWARD)
> >>>> - record_full_list = record_full_list->next;
> >>>> -
> >>>> - do
> >>>> - {
> >>>> - record_full_exec_insn (regcache, gdbarch, record_full_list);
> >>>> - if (dir == EXEC_REVERSE)
> >>>> - record_full_list = record_full_list->prev;
> >>>> - else
> >>>> - record_full_list = record_full_list->next;
> >>>> - } while (record_full_list != entry);
> >>>> + if (dir == EXEC_REVERSE)
> >>>> + for (int i = record_full_next_insn; i > target_insn; i--)
> >>>> + record_full_exec_insn (regcache, gdbarch, record_full_list[i - 1]);
> >>>> + else
> >>>> + for (int i = record_full_next_insn; i < target_insn; i++)
> >>>> + record_full_exec_insn (regcache, gdbarch, record_full_list[i]);
> >>>> }
> >>>>
> >>>> /* Alias for "target record-full". */
> >>>> @@ -2798,61 +2601,36 @@ set_record_full_insn_max_num (const
> char
> >>>> *args, int from_tty,
> >>>> static void
> >>>> maintenance_print_record_instruction (const char *args, int from_tty)
> >>>> {
> >>>> - struct record_full_entry *to_print = record_full_list;
> >>>> + if (record_full_list.empty ())
> >>>> + error (_("Not enough recorded history"));
> >>>>
> >>>> + int offset = record_full_next_insn - 1;
> >>>> + /* Reduce the offset by 1 if the record_full_next_insn is after the end
> >>>> + so that we show the last recorded instruction instead of crashing.
> */
> >>>> + if (offset == record_full_list.size ())
> >>>> + offset--;
> >>>> if (args != nullptr)
> >>>> {
> >>>> - int offset = value_as_long (parse_and_eval (args));
> >>>> - if (offset > 0)
> >>>> - {
> >>>> - /* Move forward OFFSET instructions. We know we found the
> >>>> - end of an instruction when to_print->type is record_full_end. */
> >>>> - while (to_print->next != nullptr && offset > 0)
> >>>> - {
> >>>> - to_print = to_print->next;
> >>>> - if (to_print->type == record_full_end)
> >>>> - offset--;
> >>>> - }
> >>>> - if (offset != 0)
> >>>> - error (_("Not enough recorded history"));
> >>>> - }
> >>>> - else
> >>>> - {
> >>>> - while (to_print->prev != nullptr && offset < 0)
> >>>> - {
> >>>> - to_print = to_print->prev;
> >>>> - if (to_print->type == record_full_end)
> >>>> - offset++;
> >>>> - }
> >>>> - if (offset != 0)
> >>>> - error (_("Not enough recorded history"));
> >>>> - }
> >>>> + offset += value_as_long (parse_and_eval (args));
> >>>> + if (offset >= record_full_list.size () || offset < 0)
> >>>> + error (_("Not enough recorded history"));
> >>>> }
> >>>> - gdb_assert (to_print != nullptr);
> >>>> + auto to_print = record_full_list.begin () + offset;
> >>>>
> >>>> gdbarch *arch = current_inferior ()->arch ();
> >>>>
> >>>> - /* Go back to the start of the instruction. */
> >>>> - while (to_print->prev != nullptr && to_print->prev->type !=
> >> record_full_end)
> >>>> - to_print = to_print->prev;
> >>>> -
> >>>> - /* if we're in the first record, there are no actual instructions
> >>>> - recorded. Warn the user and leave. */
> >>>> - if (to_print == &record_full_first)
> >>>> - error (_("Not enough recorded history"));
> >>>> -
> >>>> - while (to_print->type != record_full_end)
> >>>> + for (auto entry : to_print->effects)
> >>>> {
> >>>> - switch (to_print->type)
> >>>> + switch (entry.type)
> >>>> {
> >>>> case record_full_reg:
> >>>> {
> >>>> - type *regtype = gdbarch_register_type (arch, to_print-
> >>>>> u.reg.num);
> >>>> + type *regtype = gdbarch_register_type (arch, entry.u.reg.num);
> >>>> value *val
> >>>> = value_from_contents (regtype,
> >>>> - record_full_get_loc (to_print));
> >>>> + record_full_get_loc (&entry));
> >>>> gdb_printf ("Register %s changed: ",
> >>>> - gdbarch_register_name (arch, to_print-
> >>>>> u.reg.num));
> >>>> + gdbarch_register_name (arch, entry.u.reg.num));
> >>>> struct value_print_options opts;
> >>>> get_user_print_options (&opts);
> >>>> opts.raw = true;
> >>>> @@ -2862,17 +2640,16 @@ maintenance_print_record_instruction
> >> (const
> >>>> char *args, int from_tty)
> >>>> }
> >>>> case record_full_mem:
> >>>> {
> >>>> - gdb_byte *b = record_full_get_loc (to_print);
> >>>> + gdb_byte *b = record_full_get_loc (&entry);
> >>>> gdb_printf ("%d bytes of memory at address %s changed from:",
> >>>> - to_print->u.mem.len,
> >>>> - print_core_address (arch, to_print->u.mem.addr));
> >>>> - for (int i = 0; i < to_print->u.mem.len; i++)
> >>>> + entry.u.mem.len,
> >>>> + print_core_address (arch, entry.u.mem.addr));
> >>>> + for (int i = 0; i < entry.u.mem.len; i++)
> >>>> gdb_printf (" %02x", b[i]);
> >>>> gdb_printf ("\n");
> >>>> break;
> >>>> }
> >>>> }
> >>>> - to_print = to_print->next;
> >>>> }
> >>>> }
> >>>>
> >>>> @@ -2880,11 +2657,6 @@ INIT_GDB_FILE (record_full)
> >>>> {
> >>>> struct cmd_list_element *c;
> >>>>
> >>>> - /* Init record_full_first. */
> >>>> - record_full_first.prev = NULL;
> >>>> - record_full_first.next = NULL;
> >>>> - record_full_first.type = record_full_end;
> >>>> -
> >>>> add_target (record_full_target_info, record_full_open);
> >>>> add_deprecated_target_alias (record_full_target_info, "record");
> >>>> add_target (record_full_core_target_info, record_full_open);
> >>>> diff --git a/gdb/record-full.h b/gdb/record-full.h
> >>>> index 51effe74560..c327d879a8a 100644
> >>>> --- a/gdb/record-full.h
> >>>> +++ b/gdb/record-full.h
> >>>> @@ -41,7 +41,6 @@ enum record_result
> >>>>
> >>>> extern int record_full_arch_list_add_reg (struct regcache *regcache,
> int
> >>>> num);
> >>>> extern int record_full_arch_list_add_mem (CORE_ADDR addr, int len);
> >>>> -extern int record_full_arch_list_add_end (void);
> >>>>
> >>>> /* Returns true if the process record target is open. */
> >>>> extern int record_full_is_used (void);
> >>>> diff --git a/gdb/riscv-tdep.c b/gdb/riscv-tdep.c
> >>>> index 6b5c9c02d46..f5b1f66844c 100644
> >>>> --- a/gdb/riscv-tdep.c
> >>>> +++ b/gdb/riscv-tdep.c
> >>>> @@ -5466,8 +5466,5 @@ riscv_process_record (struct gdbarch
> *gdbarch,
> >>>> struct regcache *regcache,
> >>>> if (res != RECORD_SUCCESS)
> >>>> return res;
> >>>>
> >>>> - if (record_full_arch_list_add_end ())
> >>>> - return -1;
> >>>> -
> >>>> return 0;
> >>>> }
> >>>> diff --git a/gdb/rs6000-tdep.c b/gdb/rs6000-tdep.c
> >>>> index e135df94a40..f964889a49f 100644
> >>>> --- a/gdb/rs6000-tdep.c
> >>>> +++ b/gdb/rs6000-tdep.c
> >>>> @@ -7138,8 +7138,6 @@ ppc_process_prefix_instruction (int
> insn_prefix,
> >> int
> >>>> insn_suffix,
> >>>> if (record_full_arch_list_add_reg (regcache, PPC_PC_REGNUM))
> >>>> return -1;
> >>>>
> >>>> - if (record_full_arch_list_add_end ())
> >>>> - return -1;
> >>>> return 0;
> >>>> }
> >>>>
> >>>> @@ -7447,8 +7445,6 @@ ppc_process_record (struct gdbarch
> *gdbarch,
> >>>> struct regcache *regcache,
> >>>>
> >>>> if (record_full_arch_list_add_reg (regcache, PPC_PC_REGNUM))
> >>>> return -1;
> >>>> - if (record_full_arch_list_add_end ())
> >>>> - return -1;
> >>>> return 0;
> >>>> }
> >>>>
> >>>> diff --git a/gdb/s390-linux-tdep.c b/gdb/s390-linux-tdep.c
> >>>> index 3cd6b359d13..6bea30f08dc 100644
> >>>> --- a/gdb/s390-linux-tdep.c
> >>>> +++ b/gdb/s390-linux-tdep.c
> >>>> @@ -910,9 +910,6 @@ s390_linux_record_signal (struct gdbarch
> >> *gdbarch,
> >>>> struct regcache *regcache,
> >>>> if (record_full_arch_list_add_mem (sp, sizeof_rt_sigframe))
> >>>> return -1;
> >>>>
> >>>> - if (record_full_arch_list_add_end ())
> >>>> - return -1;
> >>>> -
> >>>> return 0;
> >>>> }
> >>>>
> >>>> diff --git a/gdb/s390-tdep.c b/gdb/s390-tdep.c
> >>>> index f9d7bdd04e4..36ce659ea15 100644
> >>>> --- a/gdb/s390-tdep.c
> >>>> +++ b/gdb/s390-tdep.c
> >>>> @@ -7019,8 +7019,6 @@ s390_process_record (struct gdbarch
> *gdbarch,
> >>>> struct regcache *regcache,
> >>>>
> >>>> if (record_full_arch_list_add_reg (regcache, S390_PSWA_REGNUM))
> >>>> return -1;
> >>>> - if (record_full_arch_list_add_end ())
> >>>> - return -1;
> >>>> return 0;
> >>>> }
> >>>>
> >>>> --
> >>>> 2.53.0
> >>>>
> >>> Kind Regards,
> >>> Christina
> >>>
> >>> Intel Deutschland GmbH
> >>> Registered Address: Dornacher Strasse 1, 85622 Feldkirchen, Germany
> >>> Tel: +49 89 991 430, www.intel.de
> >>> Managing Directors: Harry Demas, Jeffrey Schneiderman, Yin Chong
> Sorrell
> >>> Chairperson of the Supervisory Board: Nicole Lau
> >>> Registered Seat: Munich
> >>> Commercial Register: Amtsgericht Muenchen HRB 186928
> >>>
> > Christina
> > Intel Deutschland GmbH
> > Registered Address: Dornacher Strasse 1, 85622 Feldkirchen, Germany
> > Tel: +49 89 991 430, www.intel.de
> > Managing Directors: Harry Demas, Jeffrey Schneiderman, Yin Chong Sorrell
> > Chairperson of the Supervisory Board: Nicole Lau
> > Registered Seat: Munich
> > Commercial Register: Amtsgericht Muenchen HRB 186928
> >
>
> --
> Cheers,
> Guinevere Larsen
> It/she
Christina
Intel Deutschland GmbH
Registered Address: Dornacher Strasse 1, 85622 Feldkirchen, Germany
Tel: +49 89 991 430, www.intel.de
Managing Directors: Harry Demas, Jeffrey Schneiderman, Yin Chong Sorrell
Chairperson of the Supervisory Board: Nicole Lau
Registered Seat: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928
^ permalink raw reply [flat|nested] 19+ messages in thread
* Re: [PATCH v2 1/6] gdb/record: Refactor record history
2026-05-13 7:54 ` Schimpe, Christina
@ 2026-05-14 15:20 ` Guinevere Larsen
0 siblings, 0 replies; 19+ messages in thread
From: Guinevere Larsen @ 2026-05-14 15:20 UTC (permalink / raw)
To: Schimpe, Christina, gdb-patches
[-- Attachment #1: Type: text/plain, Size: 1386 bytes --]
On 5/13/26 4:54 AM, Schimpe, Christina wrote:
>>>>>> + record_full_incomplete_instruction.effects.shrink_to_fit ();
>>>>>> + record_full_list.push_back (record_full_incomplete_instruction);
>>> I think this line will at some point call the default copy constructor of
>> record_full_mem_entry
>>> and record_full_reg_entry, which have those buffers:
>>>
>>> gdb_byte buf[sizeof (gdb_byte *)];
>>>
>>> IIUC you'll only have a shallow copy. Should we use a std::move instead
>> here?
>> Might be worth, yeah...
>>> I further wonder if this problem might be related to the double free issues
>> you
>>> describe in patch #3. Would you mind checking?
>> I did check it! When I was working on patch #3, I disabled copy
>> construction, only allowed move constructor/assignment because I
>> specifically thought that the vector push_back was the reason for the
>> double frees, but it still happened.
> That's weird, it would have perfectly explained it.
> So with std::move we still have this problem?
> Would you mind sharing some backtrace of this double free error ?
Huh... I guess I must have done something wrong when I tried this the
last time
I just redid the changes to make the cleanup function into the
destructors and now things just worked. I'll polish it a bit and send a
v3 with that update! Thanks for getting me to try it again :)
--
Cheers,
Guinevere Larsen
It/she
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^ permalink raw reply [flat|nested] 19+ messages in thread
end of thread, other threads:[~2026-05-14 15:20 UTC | newest]
Thread overview: 19+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2026-04-23 15:25 [PATCH v2 0/6] refactor the internals of record-full Guinevere Larsen
2026-04-23 15:25 ` [PATCH v2 1/6] gdb/record: Refactor record history Guinevere Larsen
2026-04-28 3:28 ` Thiago Jung Bauermann
2026-04-28 19:54 ` Guinevere Larsen
2026-05-06 21:16 ` Schimpe, Christina
2026-05-07 17:38 ` Guinevere Larsen
2026-05-11 15:23 ` Schimpe, Christina
2026-05-12 18:50 ` Guinevere Larsen
2026-05-13 7:54 ` Schimpe, Christina
2026-05-14 15:20 ` Guinevere Larsen
2026-04-23 15:26 ` [PATCH v2 2/6] gdb/record: remove record_full_insn_num Guinevere Larsen
2026-04-23 15:26 ` [PATCH v2 3/6] gdb/record: c++ify internal structures of record-full.c Guinevere Larsen
2026-04-28 3:29 ` Thiago Jung Bauermann
2026-04-23 15:26 ` [PATCH v2 4/6] gdb/record: make record_full_history more c++-like Guinevere Larsen
2026-04-28 3:29 ` Thiago Jung Bauermann
2026-04-23 15:26 ` [PATCH v2 5/6] gdb/record: extract the PC to record_full_instruction Guinevere Larsen
2026-04-28 3:30 ` Thiago Jung Bauermann
2026-04-23 15:26 ` [PATCH v2 6/6] gdb/record: Define new version of the record-save section Guinevere Larsen
2026-04-23 15:45 ` Eli Zaretskii
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