[PATCH 1/6] gdb/record: Refactor record history

Guinevere Larsen
2026-04-15T19:00:42Z

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 | 1193 ++++++++++++++++------------------------
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, 482 insertions(+), 745 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..c9757464bb9 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 +380,121 @@ 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)
+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);
- xfree (rec);
-}
-
-/* Alloc a record_full_end record entry. */
-
-static inline struct record_full_entry *
-record_full_end_alloc (void)
-{
- struct record_full_entry *rec;
-
- rec = XCNEW (struct record_full_entry);
- rec->type = record_full_end;
-
- return rec;
-}
-
-/* Free a record_full_end record entry. */
-
-static inline void
-record_full_end_release (struct record_full_entry *rec)
-{
- xfree (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.
Return entry->type, in case caller wants to know. */

-static inline enum record_full_type
-record_full_entry_release (struct record_full_entry *rec)
+static inline void
+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 (); 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 +505,22 @@ 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 +538,6 @@ 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 +549,7 @@ 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 +557,9 @@ 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 +572,7 @@ 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 +583,12 @@ 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 +597,6 @@ 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 +628,7 @@ 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 ();
@@ -746,7 +648,7 @@ 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
+ User should understand that nothing they do during the replay
mode will change the behavior of the child. If he tries,
then that is a user error.

@@ -754,12 +656,8 @@ record_full_message (struct regcache *regcache, enum gdb_signal signal)
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 +676,11 @@ 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 +725,9 @@ 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 +805,15 @@ 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 +888,7 @@ 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 +916,7 @@ 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 +1215,6 @@ 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
{
@@ -1322,21 +1223,6 @@ 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);
- 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));
- goto replay_out;
- }
- }
-
/* If GDB is in terminal_inferior mode, it will not get the
signal. And in GDB replay mode, GDB doesn't need to be
in terminal_inferior mode, because inferior will not
@@ -1344,10 +1230,10 @@ 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 +1241,92 @@ 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);

- replay_out:
+ 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 +1334,9 @@ 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 +1424,7 @@ 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 +1434,7 @@ 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 +1443,11 @@ 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 +1466,7 @@ 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 +1501,7 @@ 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 +1534,24 @@ 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 +1713,7 @@ 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 +1769,22 @@ 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 +1813,7 @@ 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 +1839,23 @@ 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 +1871,7 @@ 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 +1879,7 @@ 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 +1887,7 @@ 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 +2157,98 @@ 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, &regnum, 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 +2276,50 @@ 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);
+ record_full_reset_incomplete ();
+ uint32_t eff_count = 0;
+ uint8_t sigval;
+ uint32_t insn_num;

- switch (rectype)
- {
- case record_full_reg: /* reg */
- /* Get register number to regnum. */
- bfdcore_read (&cbfd, osec, &regnum, 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;
+ /* 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);

- 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;
+ record_full_incomplete_instruction.insn_num = netorder32 (insn_num);
+ if (sigval != GDB_SIGNAL_0)
+ record_full_incomplete_instruction.sigval = (gdb_signal) sigval;

- 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;
+ eff_count = netorder32 (eff_count);

- default:
- error (_("Bad entry type in core file %ps."),
- styled_string (file_name_style.style (),
- bfd_get_filename (&cbfd)));
- break;
+ /* This deals with all the side effects. */
+ while (eff_count > 0)
+ {
+ eff_count--;
+
+ 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 +2328,10 @@ 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 +2365,78 @@ 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, &regnum,
+ 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 +2454,6 @@ 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 +2463,27 @@ 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 +2512,33 @@ 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, &regnum,
- 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 +2553,7 @@ 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 +2564,12 @@ 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 +2600,36 @@ 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 +2639,16 @@ 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 +2656,6 @@ 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