binutils-gdb/gdb/record-btrace.c

697 lines
16 KiB
C

/* Branch trace support for GDB, the GNU debugger.
Copyright (C) 2013 Free Software Foundation, Inc.
Contributed by Intel Corp. <markus.t.metzger@intel.com>
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "record.h"
#include "gdbthread.h"
#include "target.h"
#include "gdbcmd.h"
#include "disasm.h"
#include "observer.h"
#include "exceptions.h"
#include "cli/cli-utils.h"
#include "source.h"
#include "ui-out.h"
#include "symtab.h"
#include "filenames.h"
/* The target_ops of record-btrace. */
static struct target_ops record_btrace_ops;
/* A new thread observer enabling branch tracing for the new thread. */
static struct observer *record_btrace_thread_observer;
/* Print a record-btrace debug message. Use do ... while (0) to avoid
ambiguities when used in if statements. */
#define DEBUG(msg, args...) \
do \
{ \
if (record_debug != 0) \
fprintf_unfiltered (gdb_stdlog, \
"[record-btrace] " msg "\n", ##args); \
} \
while (0)
/* Update the branch trace for the current thread and return a pointer to its
branch trace information struct.
Throws an error if there is no thread or no trace. This function never
returns NULL. */
static struct btrace_thread_info *
require_btrace (void)
{
struct thread_info *tp;
struct btrace_thread_info *btinfo;
DEBUG ("require");
tp = find_thread_ptid (inferior_ptid);
if (tp == NULL)
error (_("No thread."));
btrace_fetch (tp);
btinfo = &tp->btrace;
if (VEC_empty (btrace_inst_s, btinfo->itrace))
error (_("No trace."));
return btinfo;
}
/* Enable branch tracing for one thread. Warn on errors. */
static void
record_btrace_enable_warn (struct thread_info *tp)
{
volatile struct gdb_exception error;
TRY_CATCH (error, RETURN_MASK_ERROR)
btrace_enable (tp);
if (error.message != NULL)
warning ("%s", error.message);
}
/* Callback function to disable branch tracing for one thread. */
static void
record_btrace_disable_callback (void *arg)
{
struct thread_info *tp;
tp = arg;
btrace_disable (tp);
}
/* Enable automatic tracing of new threads. */
static void
record_btrace_auto_enable (void)
{
DEBUG ("attach thread observer");
record_btrace_thread_observer
= observer_attach_new_thread (record_btrace_enable_warn);
}
/* Disable automatic tracing of new threads. */
static void
record_btrace_auto_disable (void)
{
/* The observer may have been detached, already. */
if (record_btrace_thread_observer == NULL)
return;
DEBUG ("detach thread observer");
observer_detach_new_thread (record_btrace_thread_observer);
record_btrace_thread_observer = NULL;
}
/* The to_open method of target record-btrace. */
static void
record_btrace_open (char *args, int from_tty)
{
struct cleanup *disable_chain;
struct thread_info *tp;
DEBUG ("open");
if (RECORD_IS_USED)
error (_("The process is already being recorded."));
if (!target_has_execution)
error (_("The program is not being run."));
if (!target_supports_btrace ())
error (_("Target does not support branch tracing."));
gdb_assert (record_btrace_thread_observer == NULL);
disable_chain = make_cleanup (null_cleanup, NULL);
ALL_THREADS (tp)
if (args == NULL || *args == 0 || number_is_in_list (args, tp->num))
{
btrace_enable (tp);
make_cleanup (record_btrace_disable_callback, tp);
}
record_btrace_auto_enable ();
push_target (&record_btrace_ops);
observer_notify_record_changed (current_inferior (), 1);
discard_cleanups (disable_chain);
}
/* The to_stop_recording method of target record-btrace. */
static void
record_btrace_stop_recording (void)
{
struct thread_info *tp;
DEBUG ("stop recording");
record_btrace_auto_disable ();
ALL_THREADS (tp)
if (tp->btrace.target != NULL)
btrace_disable (tp);
}
/* The to_close method of target record-btrace. */
static void
record_btrace_close (void)
{
/* Make sure automatic recording gets disabled even if we did not stop
recording before closing the record-btrace target. */
record_btrace_auto_disable ();
/* We already stopped recording. */
}
/* The to_info_record method of target record-btrace. */
static void
record_btrace_info (void)
{
struct btrace_thread_info *btinfo;
struct thread_info *tp;
unsigned int insts, funcs;
DEBUG ("info");
tp = find_thread_ptid (inferior_ptid);
if (tp == NULL)
error (_("No thread."));
btrace_fetch (tp);
btinfo = &tp->btrace;
insts = VEC_length (btrace_inst_s, btinfo->itrace);
funcs = VEC_length (btrace_func_s, btinfo->ftrace);
printf_unfiltered (_("Recorded %u instructions in %u functions for thread "
"%d (%s).\n"), insts, funcs, tp->num,
target_pid_to_str (tp->ptid));
}
/* Print an unsigned int. */
static void
ui_out_field_uint (struct ui_out *uiout, const char *fld, unsigned int val)
{
ui_out_field_fmt (uiout, fld, "%u", val);
}
/* Disassemble a section of the recorded instruction trace. */
static void
btrace_insn_history (struct btrace_thread_info *btinfo, struct ui_out *uiout,
unsigned int begin, unsigned int end, int flags)
{
struct gdbarch *gdbarch;
struct btrace_inst *inst;
unsigned int idx;
DEBUG ("itrace (0x%x): [%u; %u[", flags, begin, end);
gdbarch = target_gdbarch ();
for (idx = begin; VEC_iterate (btrace_inst_s, btinfo->itrace, idx, inst)
&& idx < end; ++idx)
{
/* Print the instruction index. */
ui_out_field_uint (uiout, "index", idx);
ui_out_text (uiout, "\t");
/* Disassembly with '/m' flag may not produce the expected result.
See PR gdb/11833. */
gdb_disassembly (gdbarch, uiout, NULL, flags, 1, inst->pc, inst->pc + 1);
}
}
/* The to_insn_history method of target record-btrace. */
static void
record_btrace_insn_history (int size, int flags)
{
struct btrace_thread_info *btinfo;
struct cleanup *uiout_cleanup;
struct ui_out *uiout;
unsigned int context, last, begin, end;
uiout = current_uiout;
uiout_cleanup = make_cleanup_ui_out_tuple_begin_end (uiout,
"insn history");
btinfo = require_btrace ();
last = VEC_length (btrace_inst_s, btinfo->itrace);
context = abs (size);
begin = btinfo->insn_iterator.begin;
end = btinfo->insn_iterator.end;
DEBUG ("insn-history (0x%x): %d, prev: [%u; %u[", flags, size, begin, end);
if (context == 0)
error (_("Bad record instruction-history-size."));
/* We start at the end. */
if (end < begin)
{
/* Truncate the context, if necessary. */
context = min (context, last);
end = last;
begin = end - context;
}
else if (size < 0)
{
if (begin == 0)
{
printf_unfiltered (_("At the start of the branch trace record.\n"));
btinfo->insn_iterator.end = 0;
return;
}
/* Truncate the context, if necessary. */
context = min (context, begin);
end = begin;
begin -= context;
}
else
{
if (end == last)
{
printf_unfiltered (_("At the end of the branch trace record.\n"));
btinfo->insn_iterator.begin = last;
return;
}
/* Truncate the context, if necessary. */
context = min (context, last - end);
begin = end;
end += context;
}
btrace_insn_history (btinfo, uiout, begin, end, flags);
btinfo->insn_iterator.begin = begin;
btinfo->insn_iterator.end = end;
do_cleanups (uiout_cleanup);
}
/* The to_insn_history_range method of target record-btrace. */
static void
record_btrace_insn_history_range (ULONGEST from, ULONGEST to, int flags)
{
struct btrace_thread_info *btinfo;
struct cleanup *uiout_cleanup;
struct ui_out *uiout;
unsigned int last, begin, end;
uiout = current_uiout;
uiout_cleanup = make_cleanup_ui_out_tuple_begin_end (uiout,
"insn history");
btinfo = require_btrace ();
last = VEC_length (btrace_inst_s, btinfo->itrace);
begin = (unsigned int) from;
end = (unsigned int) to;
DEBUG ("insn-history (0x%x): [%u; %u[", flags, begin, end);
/* Check for wrap-arounds. */
if (begin != from || end != to)
error (_("Bad range."));
if (end <= begin)
error (_("Bad range."));
if (last <= begin)
error (_("Range out of bounds."));
/* Truncate the range, if necessary. */
if (last < end)
end = last;
btrace_insn_history (btinfo, uiout, begin, end, flags);
btinfo->insn_iterator.begin = begin;
btinfo->insn_iterator.end = end;
do_cleanups (uiout_cleanup);
}
/* The to_insn_history_from method of target record-btrace. */
static void
record_btrace_insn_history_from (ULONGEST from, int size, int flags)
{
ULONGEST begin, end, context;
context = abs (size);
if (size < 0)
{
end = from;
if (from < context)
begin = 0;
else
begin = from - context;
}
else
{
begin = from;
end = from + context;
/* Check for wrap-around. */
if (end < begin)
end = ULONGEST_MAX;
}
record_btrace_insn_history_range (begin, end, flags);
}
/* Print the instruction number range for a function call history line. */
static void
btrace_func_history_insn_range (struct ui_out *uiout, struct btrace_func *bfun)
{
ui_out_field_uint (uiout, "insn begin", bfun->ibegin);
if (bfun->ibegin == bfun->iend)
return;
ui_out_text (uiout, "-");
ui_out_field_uint (uiout, "insn end", bfun->iend);
}
/* Print the source line information for a function call history line. */
static void
btrace_func_history_src_line (struct ui_out *uiout, struct btrace_func *bfun)
{
struct symbol *sym;
sym = bfun->sym;
if (sym == NULL)
return;
ui_out_field_string (uiout, "file",
symtab_to_filename_for_display (sym->symtab));
if (bfun->lend == 0)
return;
ui_out_text (uiout, ":");
ui_out_field_int (uiout, "min line", bfun->lbegin);
if (bfun->lend == bfun->lbegin)
return;
ui_out_text (uiout, "-");
ui_out_field_int (uiout, "max line", bfun->lend);
}
/* Disassemble a section of the recorded function trace. */
static void
btrace_func_history (struct btrace_thread_info *btinfo, struct ui_out *uiout,
unsigned int begin, unsigned int end,
enum record_print_flag flags)
{
struct btrace_func *bfun;
unsigned int idx;
DEBUG ("ftrace (0x%x): [%u; %u[", flags, begin, end);
for (idx = begin; VEC_iterate (btrace_func_s, btinfo->ftrace, idx, bfun)
&& idx < end; ++idx)
{
/* Print the function index. */
ui_out_field_uint (uiout, "index", idx);
ui_out_text (uiout, "\t");
if ((flags & record_print_insn_range) != 0)
{
btrace_func_history_insn_range (uiout, bfun);
ui_out_text (uiout, "\t");
}
if ((flags & record_print_src_line) != 0)
{
btrace_func_history_src_line (uiout, bfun);
ui_out_text (uiout, "\t");
}
if (bfun->sym != NULL)
ui_out_field_string (uiout, "function", SYMBOL_PRINT_NAME (bfun->sym));
else if (bfun->msym != NULL)
ui_out_field_string (uiout, "function", SYMBOL_PRINT_NAME (bfun->msym));
ui_out_text (uiout, "\n");
}
}
/* The to_call_history method of target record-btrace. */
static void
record_btrace_call_history (int size, int flags)
{
struct btrace_thread_info *btinfo;
struct cleanup *uiout_cleanup;
struct ui_out *uiout;
unsigned int context, last, begin, end;
uiout = current_uiout;
uiout_cleanup = make_cleanup_ui_out_tuple_begin_end (uiout,
"insn history");
btinfo = require_btrace ();
last = VEC_length (btrace_func_s, btinfo->ftrace);
context = abs (size);
begin = btinfo->func_iterator.begin;
end = btinfo->func_iterator.end;
DEBUG ("func-history (0x%x): %d, prev: [%u; %u[", flags, size, begin, end);
if (context == 0)
error (_("Bad record function-call-history-size."));
/* We start at the end. */
if (end < begin)
{
/* Truncate the context, if necessary. */
context = min (context, last);
end = last;
begin = end - context;
}
else if (size < 0)
{
if (begin == 0)
{
printf_unfiltered (_("At the start of the branch trace record.\n"));
btinfo->func_iterator.end = 0;
return;
}
/* Truncate the context, if necessary. */
context = min (context, begin);
end = begin;
begin -= context;
}
else
{
if (end == last)
{
printf_unfiltered (_("At the end of the branch trace record.\n"));
btinfo->func_iterator.begin = last;
return;
}
/* Truncate the context, if necessary. */
context = min (context, last - end);
begin = end;
end += context;
}
btrace_func_history (btinfo, uiout, begin, end, flags);
btinfo->func_iterator.begin = begin;
btinfo->func_iterator.end = end;
do_cleanups (uiout_cleanup);
}
/* The to_call_history_range method of target record-btrace. */
static void
record_btrace_call_history_range (ULONGEST from, ULONGEST to, int flags)
{
struct btrace_thread_info *btinfo;
struct cleanup *uiout_cleanup;
struct ui_out *uiout;
unsigned int last, begin, end;
uiout = current_uiout;
uiout_cleanup = make_cleanup_ui_out_tuple_begin_end (uiout,
"func history");
btinfo = require_btrace ();
last = VEC_length (btrace_func_s, btinfo->ftrace);
begin = (unsigned int) from;
end = (unsigned int) to;
DEBUG ("func-history (0x%x): [%u; %u[", flags, begin, end);
/* Check for wrap-arounds. */
if (begin != from || end != to)
error (_("Bad range."));
if (end <= begin)
error (_("Bad range."));
if (last <= begin)
error (_("Range out of bounds."));
/* Truncate the range, if necessary. */
if (last < end)
end = last;
btrace_func_history (btinfo, uiout, begin, end, flags);
btinfo->func_iterator.begin = begin;
btinfo->func_iterator.end = end;
do_cleanups (uiout_cleanup);
}
/* The to_call_history_from method of target record-btrace. */
static void
record_btrace_call_history_from (ULONGEST from, int size, int flags)
{
ULONGEST begin, end, context;
context = abs (size);
if (size < 0)
{
end = from;
if (from < context)
begin = 0;
else
begin = from - context;
}
else
{
begin = from;
end = from + context;
/* Check for wrap-around. */
if (end < begin)
end = ULONGEST_MAX;
}
record_btrace_call_history_range (begin, end, flags);
}
/* Initialize the record-btrace target ops. */
static void
init_record_btrace_ops (void)
{
struct target_ops *ops;
ops = &record_btrace_ops;
ops->to_shortname = "record-btrace";
ops->to_longname = "Branch tracing target";
ops->to_doc = "Collect control-flow trace and provide the execution history.";
ops->to_open = record_btrace_open;
ops->to_close = record_btrace_close;
ops->to_detach = record_detach;
ops->to_disconnect = record_disconnect;
ops->to_mourn_inferior = record_mourn_inferior;
ops->to_kill = record_kill;
ops->to_create_inferior = find_default_create_inferior;
ops->to_stop_recording = record_btrace_stop_recording;
ops->to_info_record = record_btrace_info;
ops->to_insn_history = record_btrace_insn_history;
ops->to_insn_history_from = record_btrace_insn_history_from;
ops->to_insn_history_range = record_btrace_insn_history_range;
ops->to_call_history = record_btrace_call_history;
ops->to_call_history_from = record_btrace_call_history_from;
ops->to_call_history_range = record_btrace_call_history_range;
ops->to_stratum = record_stratum;
ops->to_magic = OPS_MAGIC;
}
/* Alias for "target record". */
static void
cmd_record_btrace_start (char *args, int from_tty)
{
if (args != NULL && *args != 0)
error (_("Invalid argument."));
execute_command ("target record-btrace", from_tty);
}
void _initialize_record_btrace (void);
/* Initialize btrace commands. */
void
_initialize_record_btrace (void)
{
add_cmd ("btrace", class_obscure, cmd_record_btrace_start,
_("Start branch trace recording."),
&record_cmdlist);
add_alias_cmd ("b", "btrace", class_obscure, 1, &record_cmdlist);
init_record_btrace_ops ();
add_target (&record_btrace_ops);
}