From: Markus Metzger <markus.t.metzger@intel.com>
To: jan.kratochvil@redhat.com
Cc: gdb-patches@sourceware.org, Pedro Alves <palves@redhat.com>
Subject: [patch v8 03/24] gdbarch: add instruction predicate methods
Date: Thu, 12 Dec 2013 09:15:00 -0000 [thread overview]
Message-ID: <1386839747-8860-4-git-send-email-markus.t.metzger@intel.com> (raw)
In-Reply-To: <1386839747-8860-1-git-send-email-markus.t.metzger@intel.com>
Add new methods to gdbarch for analyzing the instruction at a given address.
Implement those methods for i386 and amd64 architectures.
This is needed by "record btrace" to detect function calls in the
execution trace.
CC: Pedro Alves <palves@redhat.com>
2013-12-12 Markus Metzger <markus.t.metzger@intel.com>
* amd64-tdep.c (amd64_classify_insn_at, amd64_insn_is_call,
amd64_insn_is_ret, amd64_insn_is_jump, amd64_jmp_p): New.
(amd64_init_abi): Add insn_is_call, insn_is_ret, and insn_is_jump
to gdbarch.
* i386-tdep.c (i386_insn_is_call, i386_insn_is_ret,
i386_insn_is_jump, i386_jmp_p): New.
(i386_gdbarch_init): Add insn_is_call, insn_is_ret, and
insn_is_jump to gdbarch.
* gdbarch.sh (insn_is_call, insn_is_ret, insn_is_jump): New.
* gdbarch.h: Regenerated.
* gdbarch.c: Regenerated.
* arch-utils.h (default_insn_is_call, default_insn_is_ret,
default_insn_is_jump): New.
* arch-utils.c (default_insn_is_call, default_insn_is_ret,
default_insn_is_jump): New.
---
gdb/amd64-tdep.c | 67 ++++++++++++++++++++++++++++++++++++++++++++++++++
gdb/arch-utils.c | 15 ++++++++++++
gdb/arch-utils.h | 4 +++
gdb/gdbarch.c | 75 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
gdb/gdbarch.h | 18 ++++++++++++++
gdb/gdbarch.sh | 9 +++++++
gdb/i386-tdep.c | 59 ++++++++++++++++++++++++++++++++++++++++++++
7 files changed, 247 insertions(+)
diff --git a/gdb/amd64-tdep.c b/gdb/amd64-tdep.c
index 19968fc..c6098fa 100644
--- a/gdb/amd64-tdep.c
+++ b/gdb/amd64-tdep.c
@@ -1345,6 +1345,24 @@ amd64_absolute_jmp_p (const struct amd64_insn *details)
return 0;
}
+/* Return non-zero if the instruction DETAILS is a jump, zero otherwise. */
+
+static int
+amd64_jmp_p (const struct amd64_insn *details)
+{
+ const gdb_byte *insn = &details->raw_insn[details->opcode_offset];
+
+ /* jump short, relative. */
+ if (insn[0] == 0xeb)
+ return 1;
+
+ /* jump near, relative. */
+ if (insn[0] == 0xe9)
+ return 1;
+
+ return amd64_absolute_jmp_p (details);
+}
+
static int
amd64_absolute_call_p (const struct amd64_insn *details)
{
@@ -1416,6 +1434,52 @@ amd64_syscall_p (const struct amd64_insn *details, int *lengthp)
return 0;
}
+/* Classify the instruction at ADDR using PRED.
+ Throw an error if the memory can't be read. */
+
+static int
+amd64_classify_insn_at (struct gdbarch *gdbarch, CORE_ADDR addr,
+ int (*pred) (const struct amd64_insn *))
+{
+ struct amd64_insn details;
+ gdb_byte *buf;
+ int len, classification;
+
+ len = gdbarch_max_insn_length (gdbarch);
+ buf = alloca (len);
+
+ read_code (addr, buf, len);
+ amd64_get_insn_details (buf, &details);
+
+ classification = pred (&details);
+
+ return classification;
+}
+
+/* The gdbarch insn_is_call method. */
+
+static int
+amd64_insn_is_call (struct gdbarch *gdbarch, CORE_ADDR addr)
+{
+ return amd64_classify_insn_at (gdbarch, addr, amd64_call_p);
+}
+
+/* The gdbarch insn_is_ret method. */
+
+static int
+amd64_insn_is_ret (struct gdbarch *gdbarch, CORE_ADDR addr)
+{
+ return amd64_classify_insn_at (gdbarch, addr, amd64_ret_p);
+}
+
+/* The gdbarch insn_is_jump method. */
+
+static int
+amd64_insn_is_jump (struct gdbarch *gdbarch, CORE_ADDR addr)
+{
+ return amd64_classify_insn_at (gdbarch, addr, amd64_jmp_p);
+}
+
/* Fix up the state of registers and memory after having single-stepped
a displaced instruction. */
@@ -2952,6 +3016,9 @@ amd64_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
i386_stap_is_single_operand);
set_gdbarch_stap_parse_special_token (gdbarch,
i386_stap_parse_special_token);
+ set_gdbarch_insn_is_call (gdbarch, amd64_insn_is_call);
+ set_gdbarch_insn_is_ret (gdbarch, amd64_insn_is_ret);
+ set_gdbarch_insn_is_jump (gdbarch, amd64_insn_is_jump);
}
\f
diff --git a/gdb/arch-utils.c b/gdb/arch-utils.c
index cb566ad..8fcfe91 100644
--- a/gdb/arch-utils.c
+++ b/gdb/arch-utils.c
@@ -804,6 +804,21 @@ default_return_in_first_hidden_param_p (struct gdbarch *gdbarch,
return language_pass_by_reference (type);
}
+int default_insn_is_call (struct gdbarch *gdbarch, CORE_ADDR addr)
+{
+ return 0;
+}
+
+int default_insn_is_ret (struct gdbarch *gdbarch, CORE_ADDR addr)
+{
+ return 0;
+}
+
+int default_insn_is_jump (struct gdbarch *gdbarch, CORE_ADDR addr)
+{
+ return 0;
+}
+
/* */
/* -Wmissing-prototypes */
diff --git a/gdb/arch-utils.h b/gdb/arch-utils.h
index 3f0e64f..2cf83d4 100644
--- a/gdb/arch-utils.h
+++ b/gdb/arch-utils.h
@@ -170,4 +170,8 @@ extern const char *default_auto_wide_charset (void);
extern int default_return_in_first_hidden_param_p (struct gdbarch *,
struct type *);
+
+extern int default_insn_is_call (struct gdbarch *, CORE_ADDR);
+extern int default_insn_is_ret (struct gdbarch *, CORE_ADDR);
+extern int default_insn_is_jump (struct gdbarch *, CORE_ADDR);
#endif
diff --git a/gdb/gdbarch.c b/gdb/gdbarch.c
index fb3595f..66a3c39 100644
--- a/gdb/gdbarch.c
+++ b/gdb/gdbarch.c
@@ -288,6 +288,9 @@ struct gdbarch
gdbarch_core_info_proc_ftype *core_info_proc;
gdbarch_iterate_over_objfiles_in_search_order_ftype *iterate_over_objfiles_in_search_order;
struct ravenscar_arch_ops * ravenscar_ops;
+ gdbarch_insn_is_call_ftype *insn_is_call;
+ gdbarch_insn_is_ret_ftype *insn_is_ret;
+ gdbarch_insn_is_jump_ftype *insn_is_jump;
};
@@ -461,6 +464,9 @@ struct gdbarch startup_gdbarch =
0, /* core_info_proc */
default_iterate_over_objfiles_in_search_order, /* iterate_over_objfiles_in_search_order */
NULL, /* ravenscar_ops */
+ default_insn_is_call, /* insn_is_call */
+ default_insn_is_ret, /* insn_is_ret */
+ default_insn_is_jump, /* insn_is_jump */
/* startup_gdbarch() */
};
@@ -552,6 +558,9 @@ gdbarch_alloc (const struct gdbarch_info *info,
gdbarch->gen_return_address = default_gen_return_address;
gdbarch->iterate_over_objfiles_in_search_order = default_iterate_over_objfiles_in_search_order;
gdbarch->ravenscar_ops = NULL;
+ gdbarch->insn_is_call = default_insn_is_call;
+ gdbarch->insn_is_ret = default_insn_is_ret;
+ gdbarch->insn_is_jump = default_insn_is_jump;
/* gdbarch_alloc() */
return gdbarch;
@@ -766,6 +775,12 @@ verify_gdbarch (struct gdbarch *gdbarch)
/* Skip verify of core_info_proc, has predicate. */
/* Skip verify of iterate_over_objfiles_in_search_order, invalid_p == 0 */
/* Skip verify of ravenscar_ops, invalid_p == 0 */
+ if (gdbarch->insn_is_call == default_insn_is_call)
+ fprintf_unfiltered (log, "\n\tinsn_is_call");
+ if (gdbarch->insn_is_ret == default_insn_is_ret)
+ fprintf_unfiltered (log, "\n\tinsn_is_ret");
+ if (gdbarch->insn_is_jump == default_insn_is_jump)
+ fprintf_unfiltered (log, "\n\tinsn_is_jump");
buf = ui_file_xstrdup (log, &length);
make_cleanup (xfree, buf);
if (length > 0)
@@ -1099,6 +1114,15 @@ gdbarch_dump (struct gdbarch *gdbarch, struct ui_file *file)
"gdbarch_dump: inner_than = <%s>\n",
host_address_to_string (gdbarch->inner_than));
fprintf_unfiltered (file,
+ "gdbarch_dump: insn_is_call = <%s>\n",
+ host_address_to_string (gdbarch->insn_is_call));
+ fprintf_unfiltered (file,
+ "gdbarch_dump: insn_is_jump = <%s>\n",
+ host_address_to_string (gdbarch->insn_is_jump));
+ fprintf_unfiltered (file,
+ "gdbarch_dump: insn_is_ret = <%s>\n",
+ host_address_to_string (gdbarch->insn_is_ret));
+ fprintf_unfiltered (file,
"gdbarch_dump: int_bit = %s\n",
plongest (gdbarch->int_bit));
fprintf_unfiltered (file,
@@ -4422,6 +4446,57 @@ set_gdbarch_ravenscar_ops (struct gdbarch *gdbarch,
gdbarch->ravenscar_ops = ravenscar_ops;
}
+int
+gdbarch_insn_is_call (struct gdbarch *gdbarch, CORE_ADDR addr)
+{
+ gdb_assert (gdbarch != NULL);
+ gdb_assert (gdbarch->insn_is_call != NULL);
+ if (gdbarch_debug >= 2)
+ fprintf_unfiltered (gdb_stdlog, "gdbarch_insn_is_call called\n");
+ return gdbarch->insn_is_call (gdbarch, addr);
+}
+
+void
+set_gdbarch_insn_is_call (struct gdbarch *gdbarch,
+ gdbarch_insn_is_call_ftype insn_is_call)
+{
+ gdbarch->insn_is_call = insn_is_call;
+}
+
+int
+gdbarch_insn_is_ret (struct gdbarch *gdbarch, CORE_ADDR addr)
+{
+ gdb_assert (gdbarch != NULL);
+ gdb_assert (gdbarch->insn_is_ret != NULL);
+ if (gdbarch_debug >= 2)
+ fprintf_unfiltered (gdb_stdlog, "gdbarch_insn_is_ret called\n");
+ return gdbarch->insn_is_ret (gdbarch, addr);
+}
+
+void
+set_gdbarch_insn_is_ret (struct gdbarch *gdbarch,
+ gdbarch_insn_is_ret_ftype insn_is_ret)
+{
+ gdbarch->insn_is_ret = insn_is_ret;
+}
+
+int
+gdbarch_insn_is_jump (struct gdbarch *gdbarch, CORE_ADDR addr)
+{
+ gdb_assert (gdbarch != NULL);
+ gdb_assert (gdbarch->insn_is_jump != NULL);
+ if (gdbarch_debug >= 2)
+ fprintf_unfiltered (gdb_stdlog, "gdbarch_insn_is_jump called\n");
+ return gdbarch->insn_is_jump (gdbarch, addr);
+}
+
+void
+set_gdbarch_insn_is_jump (struct gdbarch *gdbarch,
+ gdbarch_insn_is_jump_ftype insn_is_jump)
+{
+ gdbarch->insn_is_jump = insn_is_jump;
+}
+
/* Keep a registry of per-architecture data-pointers required by GDB
modules. */
diff --git a/gdb/gdbarch.h b/gdb/gdbarch.h
index b58efc8..c8a8a12 100644
--- a/gdb/gdbarch.h
+++ b/gdb/gdbarch.h
@@ -1261,6 +1261,24 @@ extern void set_gdbarch_iterate_over_objfiles_in_search_order (struct gdbarch *g
extern struct ravenscar_arch_ops * gdbarch_ravenscar_ops (struct gdbarch *gdbarch);
extern void set_gdbarch_ravenscar_ops (struct gdbarch *gdbarch, struct ravenscar_arch_ops * ravenscar_ops);
+/* Return non-zero if the instruction at ADDR is a call; zero otherwise. */
+
+typedef int (gdbarch_insn_is_call_ftype) (struct gdbarch *gdbarch, CORE_ADDR addr);
+extern int gdbarch_insn_is_call (struct gdbarch *gdbarch, CORE_ADDR addr);
+extern void set_gdbarch_insn_is_call (struct gdbarch *gdbarch, gdbarch_insn_is_call_ftype *insn_is_call);
+
+/* Return non-zero if the instruction at ADDR is a return; zero otherwise. */
+
+typedef int (gdbarch_insn_is_ret_ftype) (struct gdbarch *gdbarch, CORE_ADDR addr);
+extern int gdbarch_insn_is_ret (struct gdbarch *gdbarch, CORE_ADDR addr);
+extern void set_gdbarch_insn_is_ret (struct gdbarch *gdbarch, gdbarch_insn_is_ret_ftype *insn_is_ret);
+
+/* Return non-zero if the instruction at ADDR is a jump; zero otherwise. */
+
+typedef int (gdbarch_insn_is_jump_ftype) (struct gdbarch *gdbarch, CORE_ADDR addr);
+extern int gdbarch_insn_is_jump (struct gdbarch *gdbarch, CORE_ADDR addr);
+extern void set_gdbarch_insn_is_jump (struct gdbarch *gdbarch, gdbarch_insn_is_jump_ftype *insn_is_jump);
+
/* Definition for an unknown syscall, used basically in error-cases. */
#define UNKNOWN_SYSCALL (-1)
diff --git a/gdb/gdbarch.sh b/gdb/gdbarch.sh
index a678a78..a9e08ba 100755
--- a/gdb/gdbarch.sh
+++ b/gdb/gdbarch.sh
@@ -988,6 +988,15 @@ m:void:iterate_over_objfiles_in_search_order:iterate_over_objfiles_in_search_ord
# Ravenscar arch-dependent ops.
v:struct ravenscar_arch_ops *:ravenscar_ops:::NULL:NULL::0:host_address_to_string (gdbarch->ravenscar_ops)
+
+# Return non-zero if the instruction at ADDR is a call; zero otherwise.
+m:int:insn_is_call:CORE_ADDR addr:addr::default_insn_is_call
+
+# Return non-zero if the instruction at ADDR is a return; zero otherwise.
+m:int:insn_is_ret:CORE_ADDR addr:addr::default_insn_is_ret
+
+# Return non-zero if the instruction at ADDR is a jump; zero otherwise.
+m:int:insn_is_jump:CORE_ADDR addr:addr::default_insn_is_jump
EOF
}
diff --git a/gdb/i386-tdep.c b/gdb/i386-tdep.c
index a1a4453..326e4c3 100644
--- a/gdb/i386-tdep.c
+++ b/gdb/i386-tdep.c
@@ -530,6 +530,22 @@ i386_absolute_jmp_p (const gdb_byte *insn)
return 0;
}
+/* Return non-zero if INSN is a jump, zero otherwise. */
+
+static int
+i386_jmp_p (const gdb_byte *insn)
+{
+ /* jump short, relative. */
+ if (insn[0] == 0xeb)
+ return 1;
+
+ /* jump near, relative. */
+ if (insn[0] == 0xe9)
+ return 1;
+
+ return i386_absolute_jmp_p (insn);
+}
+
static int
i386_absolute_call_p (const gdb_byte *insn)
{
@@ -601,6 +617,45 @@ i386_syscall_p (const gdb_byte *insn, int *lengthp)
return 0;
}
+/* The gdbarch insn_is_call method. */
+
+static int
+i386_insn_is_call (struct gdbarch *gdbarch, CORE_ADDR addr)
+{
+ gdb_byte buf[I386_MAX_INSN_LEN], *insn;
+
+ read_code (addr, buf, I386_MAX_INSN_LEN);
+ insn = i386_skip_prefixes (buf, I386_MAX_INSN_LEN);
+
+ return i386_call_p (insn);
+}
+
+/* The gdbarch insn_is_ret method. */
+
+static int
+i386_insn_is_ret (struct gdbarch *gdbarch, CORE_ADDR addr)
+{
+ gdb_byte buf[I386_MAX_INSN_LEN], *insn;
+
+ read_code (addr, buf, I386_MAX_INSN_LEN);
+ insn = i386_skip_prefixes (buf, I386_MAX_INSN_LEN);
+
+ return i386_ret_p (insn);
+}
+
+/* The gdbarch insn_is_jump method. */
+
+static int
+i386_insn_is_jump (struct gdbarch *gdbarch, CORE_ADDR addr)
+{
+ gdb_byte buf[I386_MAX_INSN_LEN], *insn;
+
+ read_code (addr, buf, I386_MAX_INSN_LEN);
+ insn = i386_skip_prefixes (buf, I386_MAX_INSN_LEN);
+
+ return i386_jmp_p (insn);
+}
+
/* Some kernels may run one past a syscall insn, so we have to cope.
Otherwise this is just simple_displaced_step_copy_insn. */
@@ -7966,6 +8021,10 @@ i386_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
set_gdbarch_gen_return_address (gdbarch, i386_gen_return_address);
+ set_gdbarch_insn_is_call (gdbarch, i386_insn_is_call);
+ set_gdbarch_insn_is_ret (gdbarch, i386_insn_is_ret);
+ set_gdbarch_insn_is_jump (gdbarch, i386_insn_is_jump);
+
/* Hook in ABI-specific overrides, if they have been registered. */
info.tdep_info = (void *) tdesc_data;
gdbarch_init_osabi (info, gdbarch);
--
1.8.3.1
next prev parent reply other threads:[~2013-12-12 9:15 UTC|newest]
Thread overview: 73+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-12-12 9:15 [patch v8 00/24] record-btrace: reverse Markus Metzger
2013-12-12 9:15 ` [patch v8 16/24] record-btrace, frame: supply target-specific unwinder Markus Metzger
2013-12-12 9:15 ` [patch v8 01/24] btrace, linux: fix memory leak when reading branch trace Markus Metzger
2013-12-12 9:15 ` [patch v8 14/24] record-btrace: supply register target methods Markus Metzger
2013-12-12 9:15 ` Markus Metzger [this message]
2013-12-12 9:16 ` [patch v8 18/24] record-btrace: add to_wait and to_resume " Markus Metzger
2013-12-12 9:16 ` [patch v8 08/24] record-btrace: start counting at one Markus Metzger
2013-12-12 9:16 ` [patch v8 07/24] record-btrace: fix insn range in function call history Markus Metzger
2013-12-12 9:16 ` [patch v8 11/24] record-btrace: make ranges include begin and end Markus Metzger
2013-12-13 17:56 ` Pedro Alves
2013-12-12 9:16 ` [patch v8 15/24] frame, backtrace: allow targets to supply a frame unwinder Markus Metzger
2013-12-13 18:27 ` Pedro Alves
2013-12-16 9:18 ` Metzger, Markus T
2013-12-16 19:02 ` Pedro Alves
2013-12-17 8:26 ` Metzger, Markus T
2013-12-17 9:48 ` Pedro Alves
2013-12-12 9:16 ` [patch v8 17/24] record-btrace: provide xfer_partial target method Markus Metzger
2013-12-13 18:43 ` Pedro Alves
2013-12-16 10:53 ` Metzger, Markus T
2013-12-16 19:16 ` Pedro Alves
2013-12-17 11:58 ` Metzger, Markus T
2013-12-17 16:56 ` Pedro Alves
2013-12-18 9:26 ` Metzger, Markus T
2013-12-18 10:39 ` Pedro Alves
2013-12-12 9:16 ` [patch v8 13/24] target: add ops parameter to to_prepare_to_store method Markus Metzger
2013-12-12 9:16 ` [patch v8 10/24] record-btrace: optionally indent function call history Markus Metzger
2013-12-12 9:16 ` [patch v8 22/24] btrace, gdbserver: read branch trace incrementally Markus Metzger
2013-12-13 19:46 ` Pedro Alves
2013-12-16 12:47 ` Metzger, Markus T
2013-12-16 19:23 ` Pedro Alves
2013-12-12 9:16 ` [patch v8 04/24] frame: add frame_is_tailcall function Markus Metzger
2013-12-12 9:16 ` [patch v8 21/24] record-btrace: extend unwinder Markus Metzger
2013-12-13 19:45 ` Pedro Alves
2013-12-16 12:42 ` Metzger, Markus T
2013-12-16 19:22 ` Pedro Alves
2013-12-17 12:56 ` Metzger, Markus T
2013-12-12 9:16 ` [patch v8 20/24] record-btrace: add record goto target methods Markus Metzger
2013-12-12 9:16 ` [patch v8 23/24] record-btrace: show trace from enable location Markus Metzger
2013-12-13 19:50 ` Pedro Alves
2013-12-16 12:57 ` Metzger, Markus T
2013-12-16 19:41 ` Pedro Alves
2013-12-17 13:20 ` Metzger, Markus T
2013-12-17 16:59 ` Pedro Alves
2013-12-12 9:16 ` [patch v8 05/24] frame: artificial frame id's Markus Metzger
2013-12-12 19:39 ` Pedro Alves
2013-12-12 19:55 ` Jan Kratochvil
2013-12-13 8:04 ` Metzger, Markus T
2013-12-13 11:27 ` Jan Kratochvil
2013-12-13 11:42 ` Metzger, Markus T
2013-12-13 12:09 ` Pedro Alves
2013-12-13 13:01 ` Metzger, Markus T
2013-12-13 15:44 ` Pedro Alves
2013-12-13 17:51 ` Pedro Alves
2013-12-18 13:30 ` Metzger, Markus T
2013-12-12 9:16 ` [patch v8 19/24] record-btrace: provide target_find_new_threads method Markus Metzger
2013-12-12 9:16 ` [patch v8 12/24] btrace: add replay position to btrace thread info Markus Metzger
2013-12-12 9:16 ` [patch v8 09/24] btrace: increase buffer size Markus Metzger
2013-12-12 9:16 ` [patch v8 06/24] btrace: change branch trace data structure Markus Metzger
2013-12-12 9:16 ` [patch v8 24/24] record-btrace: add (reverse-)stepping support Markus Metzger
2013-12-12 16:36 ` Eli Zaretskii
2013-12-13 19:22 ` Pedro Alves
2013-12-16 15:56 ` Metzger, Markus T
2013-12-16 20:30 ` Pedro Alves
2013-12-17 14:14 ` Metzger, Markus T
2013-12-17 15:07 ` Metzger, Markus T
2013-12-17 15:48 ` Metzger, Markus T
2013-12-17 20:41 ` Pedro Alves
2013-12-17 20:34 ` Pedro Alves
2013-12-17 20:07 ` Pedro Alves
2013-12-18 9:44 ` Metzger, Markus T
2013-12-12 9:16 ` [patch v8 02/24] btrace: uppercase btrace_read_type Markus Metzger
2013-12-12 14:07 ` [patch v8 00/24] record-btrace: reverse Jan Kratochvil
2013-12-12 14:19 ` Metzger, Markus T
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