Target interface for reverse debugging.
* target.h (enum target_waitkind):
Add new wait event, TARGET_WAITKIND_NO_HISTORY.
(struct target_ops): New method to_can_execute_reverse.
(target_can_execute_reverse): New macro.
* target.c (update_current_target): Inherit to_can_execute_reverse.
Remote interface for reverse debugging.
* remote.c (remote_can_execute_reverse): New target method.
(remote_resume): Check for reverse exec direction, and send
appropriate command to target.
(remote_wait_as): Check target response for NO_HISTORY status.
Also check for empty reply (target doesn't understand "bs" or "bc).
(remote_vcont_resume): Jump out if attempting reverse execution.
Event handling interface for reverse debugging.
* infrun.c (execution_direction): New state variable.
(enum inferior_stop_reason): Add NO_HISTORY reason.
(handle_inferior_event): Handle TARGET_WAITKIND_NO_HISTORY.
Handle stepping over a function call in reverse.
Handle stepping thru a line range in reverse.
Handle setting a step-resume breakpoint in reverse.
Handle stepping into a function in reverse.
Handle stepping between line ranges in reverse.
(print_stop_reason): Print reason for NO_HISTORY.
(step_into_function): Rename to handle_step_into_function.
(handle_step_into_function_backward): New function.
(set_exec_direction_func, show_exec_direction_func): New funcs.
(proceed): No need to singlestep over a breakpoint
when resuming in reverse.
* inferior.h (enum exec_direction_kind): New enum.
(execution_direction): Export new execution state variable.
* breakpoint.c (make_breakpoint_silent): New function.
* breakpoint.h (make_breakpoint_silent): Export.
* infcmd.c (finish_command): Check for reverse exec direction.
(finish_backward): New function, handle finish cmd in reverse.
User interface for reverse execution.
* Makefile.in (reverse.c): New file.
* reverse.c: New file. User interface for reverse execution.
+2008-10-17 Michael Snyder <msnyder@vmware.com>
+ Target interface for reverse debugging.
+ * target.h (enum target_waitkind):
+ Add new wait event, TARGET_WAITKIND_NO_HISTORY.
+ (struct target_ops): New method to_can_execute_reverse.
+ (target_can_execute_reverse): New macro.
+ * target.c (update_current_target): Inherit to_can_execute_reverse.
+
+ Remote interface for reverse debugging.
+ * remote.c (remote_can_execute_reverse): New target method.
+ (remote_resume): Check for reverse exec direction, and send
+ appropriate command to target.
+ (remote_wait_as): Check target response for NO_HISTORY status.
+ Also check for empty reply (target doesn't understand "bs" or "bc).
+ (remote_vcont_resume): Jump out if attempting reverse execution.
+
+ Event handling interface for reverse debugging.
+ * infrun.c (execution_direction): New state variable.
+ (enum inferior_stop_reason): Add NO_HISTORY reason.
+ (handle_inferior_event): Handle TARGET_WAITKIND_NO_HISTORY.
+ Handle stepping over a function call in reverse.
+ Handle stepping thru a line range in reverse.
+ Handle setting a step-resume breakpoint in reverse.
+ Handle stepping into a function in reverse.
+ Handle stepping between line ranges in reverse.
+ (print_stop_reason): Print reason for NO_HISTORY.
+ (step_into_function): Rename to handle_step_into_function.
+ (handle_step_into_function_backward): New function.
+ (set_exec_direction_func, show_exec_direction_func): New funcs.
+ (proceed): No need to singlestep over a breakpoint
+ when resuming in reverse.
+
+ * inferior.h (enum exec_direction_kind): New enum.
+ (execution_direction): Export new execution state variable.
+
+ * breakpoint.c (make_breakpoint_silent): New function.
+ * breakpoint.h (make_breakpoint_silent): Export.
+ * infcmd.c (finish_command): Check for reverse exec direction.
+ (finish_backward): New function, handle finish cmd in reverse.
+
+ User interface for reverse execution.
+ * Makefile.in (reverse.c): New file.
+ * reverse.c: New file. User interface for reverse execution.
+
2008-10-17 Pedro Alves <pedro@codesourcery.com>
* remote.c (record_currthread): Add inferior before child threads.
objfiles.c osabi.c observer.c \
p-exp.y p-lang.c p-typeprint.c p-valprint.c parse.c printcmd.c \
prologue-value.c \
- regcache.c reggroups.c remote.c remote-fileio.c \
+ regcache.c reggroups.c remote.c remote-fileio.c reverse.c \
scm-exp.c scm-lang.c scm-valprint.c \
sentinel-frame.c \
serial.c ser-base.c ser-unix.c \
findcmd.o \
std-regs.o \
signals.o \
- exec.o bcache.o objfiles.o observer.o minsyms.o maint.o demangle.o \
+ exec.o reverse.o \
+ bcache.o objfiles.o observer.o minsyms.o maint.o demangle.o \
dbxread.o coffread.o coff-pe-read.o \
dwarf2read.o mipsread.o stabsread.o corefile.o \
dwarf2expr.o dwarf2loc.o dwarf2-frame.o \
error (_("No breakpoint number %d."), bptnum);
}
+void
+make_breakpoint_silent (struct breakpoint *b)
+{
+ /* Silence the breakpoint. */
+ b->silent = 1;
+}
+
/* Command to set ignore-count of breakpoint N to COUNT. */
static void
in our opinion won't ever trigger. */
extern void breakpoint_retire_moribund (void);
+/* Tell a breakpoint to be quiet. */
+extern void make_breakpoint_silent (struct breakpoint *);
+
#endif /* !defined (BREAKPOINT_H) */
xfree (arg);
}
+/* finish_backward -- helper function for finish_command. */
+
+static void
+finish_backward (struct symbol *function)
+{
+ struct symtab_and_line sal;
+ struct thread_info *tp = inferior_thread ();
+ struct breakpoint *breakpoint;
+ struct cleanup *old_chain;
+ CORE_ADDR func_addr;
+ int back_up;
+
+ if (find_pc_partial_function (get_frame_pc (get_current_frame ()),
+ NULL, &func_addr, NULL) == 0)
+ internal_error (__FILE__, __LINE__,
+ _("Finish: couldn't find function."));
+
+ sal = find_pc_line (func_addr, 0);
+
+ /* We don't need a return value. */
+ tp->proceed_to_finish = 0;
+ /* Special case: if we're sitting at the function entry point,
+ then all we need to do is take a reverse singlestep. We
+ don't need to set a breakpoint, and indeed it would do us
+ no good to do so.
+
+ Note that this can only happen at frame #0, since there's
+ no way that a function up the stack can have a return address
+ that's equal to its entry point. */
+
+ if (sal.pc != read_pc ())
+ {
+ /* Set breakpoint and continue. */
+ breakpoint =
+ set_momentary_breakpoint (sal,
+ get_frame_id (get_selected_frame (NULL)),
+ bp_breakpoint);
+ /* Tell the breakpoint to keep quiet. We won't be done
+ until we've done another reverse single-step. */
+ make_breakpoint_silent (breakpoint);
+ old_chain = make_cleanup_delete_breakpoint (breakpoint);
+ proceed ((CORE_ADDR) -1, TARGET_SIGNAL_DEFAULT, 0);
+ /* We will be stopped when proceed returns. */
+ back_up = bpstat_find_breakpoint (tp->stop_bpstat, breakpoint) != NULL;
+ do_cleanups (old_chain);
+ }
+ else
+ back_up = 1;
+ if (back_up)
+ {
+ /* If in fact we hit the step-resume breakpoint (and not
+ some other breakpoint), then we're almost there --
+ we just need to back up by one more single-step. */
+ tp->step_range_start = tp->step_range_end = 1;
+ proceed ((CORE_ADDR) -1, TARGET_SIGNAL_DEFAULT, 1);
+ }
+ return;
+}
+
+/* finish_forward -- helper function for finish_command. */
+
+static void
+finish_forward (struct symbol *function, struct frame_info *frame)
+{
+ struct symtab_and_line sal;
+ struct thread_info *tp = inferior_thread ();
+ struct breakpoint *breakpoint;
+ struct cleanup *old_chain;
+ struct finish_command_continuation_args *cargs;
+
+ sal = find_pc_line (get_frame_pc (frame), 0);
+ sal.pc = get_frame_pc (frame);
+
+ breakpoint = set_momentary_breakpoint (sal, get_frame_id (frame),
+ bp_finish);
+
+ old_chain = make_cleanup_delete_breakpoint (breakpoint);
+
+ tp->proceed_to_finish = 1; /* We want stop_registers, please... */
+ make_cleanup_restore_integer (&suppress_stop_observer);
+ suppress_stop_observer = 1;
+ proceed ((CORE_ADDR) -1, TARGET_SIGNAL_DEFAULT, 0);
+
+ cargs = xmalloc (sizeof (*cargs));
+
+ cargs->breakpoint = breakpoint;
+ cargs->function = function;
+ add_continuation (tp, finish_command_continuation, cargs,
+ finish_command_continuation_free_arg);
+
+ discard_cleanups (old_chain);
+ if (!target_can_async_p ())
+ do_all_continuations ();
+}
+
/* "finish": Set a temporary breakpoint at the place the selected
frame will return to, then continue. */
static void
finish_command (char *arg, int from_tty)
{
- struct symtab_and_line sal;
struct frame_info *frame;
struct symbol *function;
- struct breakpoint *breakpoint;
- struct cleanup *old_chain;
- struct finish_command_continuation_args *cargs;
- struct thread_info *tp;
int async_exec = 0;
if (async_exec && !target_can_async_p ())
error (_("Asynchronous execution not supported on this target."));
+ /* Don't try to async in reverse. */
+ if (async_exec && execution_direction == EXEC_REVERSE)
+ error (_("Asynchronous 'finish' not supported in reverse."));
+
/* If we are not asked to run in the bg, then prepare to run in the
foreground, synchronously. */
if (!async_exec && target_can_async_p ())
if (frame == 0)
error (_("\"finish\" not meaningful in the outermost frame."));
- tp = inferior_thread ();
-
clear_proceed_status ();
- sal = find_pc_line (get_frame_pc (frame), 0);
- sal.pc = get_frame_pc (frame);
-
- breakpoint = set_momentary_breakpoint (sal, get_frame_id (frame), bp_finish);
-
- old_chain = make_cleanup_delete_breakpoint (breakpoint);
-
/* Find the function we will return from. */
function = find_pc_function (get_frame_pc (get_selected_frame (NULL)));
source. */
if (from_tty)
{
- printf_filtered (_("Run till exit from "));
+ if (execution_direction == EXEC_REVERSE)
+ printf_filtered (_("Run back to call of "));
+ else
+ printf_filtered (_("Run till exit from "));
+
print_stack_frame (get_selected_frame (NULL), 1, LOCATION);
}
- tp->proceed_to_finish = 1; /* We want stop_registers, please... */
- make_cleanup_restore_integer (&suppress_stop_observer);
- suppress_stop_observer = 1;
- proceed ((CORE_ADDR) -1, TARGET_SIGNAL_DEFAULT, 0);
-
- cargs = xmalloc (sizeof (*cargs));
-
- cargs->breakpoint = breakpoint;
- cargs->function = function;
- add_continuation (tp, finish_command_continuation, cargs,
- finish_command_continuation_free_arg);
-
- discard_cleanups (old_chain);
- if (!target_can_async_p ())
- do_all_continuations ();
+ if (execution_direction == EXEC_REVERSE)
+ finish_backward (function);
+ else
+ finish_forward (function, frame);
}
\f
STOP_QUIETLY_NO_SIGSTOP
};
+/* Reverse execution. */
+enum exec_direction_kind
+ {
+ EXEC_FORWARD,
+ EXEC_REVERSE,
+ EXEC_ERROR
+ };
+
+extern enum exec_direction_kind execution_direction;
+
/* Nonzero if proceed is being used for a "finish" command or a similar
situation when stop_registers should be saved. */
if (addr == (CORE_ADDR) -1)
{
- if (pc == stop_pc && breakpoint_here_p (pc))
+ if (pc == stop_pc && breakpoint_here_p (pc)
+ && execution_direction != EXEC_REVERSE)
/* There is a breakpoint at the address we will resume at,
step one instruction before inserting breakpoints so that
we do not stop right away (and report a second hit at this
- breakpoint). */
+ breakpoint).
+
+ Note, we don't do this in reverse, because we won't
+ actually be executing the breakpoint insn anyway.
+ We'll be (un-)executing the previous instruction. */
+
oneproc = 1;
else if (gdbarch_single_step_through_delay_p (gdbarch)
&& gdbarch_single_step_through_delay (gdbarch,
/* Inferior exited. */
EXITED,
/* Inferior received signal, and user asked to be notified. */
- SIGNAL_RECEIVED
+ SIGNAL_RECEIVED,
+ /* Reverse execution -- target ran out of history info. */
+ NO_HISTORY
};
/* The PTID we'll do a target_wait on.*/
void handle_inferior_event (struct execution_control_state *ecs);
-static void step_into_function (struct execution_control_state *ecs);
+static void handle_step_into_function (struct execution_control_state *ecs);
+static void handle_step_into_function_backward (struct execution_control_state *ecs);
static void insert_step_resume_breakpoint_at_frame (struct frame_info *step_frame);
static void insert_step_resume_breakpoint_at_caller (struct frame_info *);
static void insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal,
ecs->event_thread->stop_signal = ecs->ws.value.sig;
break;
+ case TARGET_WAITKIND_NO_HISTORY:
+ /* Reverse execution: target ran out of history info. */
+ print_stop_reason (NO_HISTORY, 0);
+ stop_stepping (ecs);
+ return;
+
/* We had an event in the inferior, but we are not interested
in handling it at this level. The lower layers have already
done what needs to be done, if anything.
keep_going (ecs);
return;
}
+ if (stop_pc == ecs->stop_func_start
+ && execution_direction == EXEC_REVERSE)
+ {
+ /* We are stepping over a function call in reverse, and
+ just hit the step-resume breakpoint at the start
+ address of the function. Go back to single-stepping,
+ which should take us back to the function call. */
+ ecs->event_thread->stepping_over_breakpoint = 1;
+ keep_going (ecs);
+ return;
+ }
break;
case BPSTAT_WHAT_CHECK_SHLIBS:
&& stop_pc < ecs->event_thread->step_range_end)
{
if (debug_infrun)
- fprintf_unfiltered (gdb_stdlog, "infrun: stepping inside range [0x%s-0x%s]\n",
+ fprintf_unfiltered (gdb_stdlog, "infrun: stepping inside range [0x%s-0x%s]\n",
paddr_nz (ecs->event_thread->step_range_start),
paddr_nz (ecs->event_thread->step_range_end));
- keep_going (ecs);
+
+ /* When stepping backward, stop at beginning of line range
+ (unless it's the function entry point, in which case
+ keep going back to the call point). */
+ if (stop_pc == ecs->event_thread->step_range_start
+ && stop_pc != ecs->stop_func_start
+ && execution_direction == EXEC_REVERSE)
+ {
+ ecs->event_thread->stop_step = 1;
+ print_stop_reason (END_STEPPING_RANGE, 0);
+ stop_stepping (ecs);
+ }
+ else
+ keep_going (ecs);
+
return;
}
previous frame must have valid frame IDs. */
if (!frame_id_eq (get_frame_id (get_current_frame ()),
ecs->event_thread->step_frame_id)
- && frame_id_eq (frame_unwind_id (get_current_frame ()),
- ecs->event_thread->step_frame_id))
+ && (frame_id_eq (frame_unwind_id (get_current_frame ()),
+ ecs->event_thread->step_frame_id)
+ || execution_direction == EXEC_REVERSE))
{
CORE_ADDR real_stop_pc;
if (ecs->event_thread->step_over_calls == STEP_OVER_ALL)
{
- /* We're doing a "next", set a breakpoint at callee's return
- address (the address at which the caller will
- resume). */
- insert_step_resume_breakpoint_at_caller (get_current_frame ());
+ /* We're doing a "next".
+
+ Normal (forward) execution: set a breakpoint at the
+ callee's return address (the address at which the caller
+ will resume).
+
+ Reverse (backward) execution. set the step-resume
+ breakpoint at the start of the function that we just
+ stepped into (backwards), and continue to there. When we
+ get there, we'll need to single-step back to the
+ caller. */
+
+ if (execution_direction == EXEC_REVERSE)
+ {
+ struct symtab_and_line sr_sal;
+ init_sal (&sr_sal);
+ sr_sal.pc = ecs->stop_func_start;
+ insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
+ }
+ else
+ insert_step_resume_breakpoint_at_caller (get_current_frame ());
+
keep_going (ecs);
return;
}
tmp_sal = find_pc_line (ecs->stop_func_start, 0);
if (tmp_sal.line != 0)
{
- step_into_function (ecs);
+ if (execution_direction == EXEC_REVERSE)
+ handle_step_into_function_backward (ecs);
+ else
+ handle_step_into_function (ecs);
return;
}
}
return;
}
- /* Set a breakpoint at callee's return address (the address at
- which the caller will resume). */
- insert_step_resume_breakpoint_at_caller (get_current_frame ());
+ if (execution_direction == EXEC_REVERSE)
+ {
+ /* Set a breakpoint at callee's start address.
+ From there we can step once and be back in the caller. */
+ struct symtab_and_line sr_sal;
+ init_sal (&sr_sal);
+ sr_sal.pc = ecs->stop_func_start;
+ insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
+ }
+ else
+ /* Set a breakpoint at callee's return address (the address
+ at which the caller will resume). */
+ insert_step_resume_breakpoint_at_caller (get_current_frame ());
+
keep_going (ecs);
return;
}
|| bpstat_should_step ());
}
-/* Subroutine call with source code we should not step over. Do step
- to the first line of code in it. */
+/* Inferior has stepped into a subroutine call with source code that
+ we should not step over. Do step to the first line of code in
+ it. */
static void
-step_into_function (struct execution_control_state *ecs)
+handle_step_into_function (struct execution_control_state *ecs)
{
struct symtab *s;
struct symtab_and_line stop_func_sal, sr_sal;
s = find_pc_symtab (stop_pc);
if (s && s->language != language_asm)
- ecs->stop_func_start = gdbarch_skip_prologue
- (current_gdbarch, ecs->stop_func_start);
+ ecs->stop_func_start = gdbarch_skip_prologue (current_gdbarch,
+ ecs->stop_func_start);
stop_func_sal = find_pc_line (ecs->stop_func_start, 0);
/* Use the step_resume_break to step until the end of the prologue,
keep_going (ecs);
}
+/* Inferior has stepped backward into a subroutine call with source
+ code that we should not step over. Do step to the beginning of the
+ last line of code in it. */
+
+static void
+handle_step_into_function_backward (struct execution_control_state *ecs)
+{
+ struct symtab *s;
+ struct symtab_and_line stop_func_sal, sr_sal;
+
+ s = find_pc_symtab (stop_pc);
+ if (s && s->language != language_asm)
+ ecs->stop_func_start = gdbarch_skip_prologue (current_gdbarch,
+ ecs->stop_func_start);
+
+ stop_func_sal = find_pc_line (stop_pc, 0);
+
+ /* OK, we're just going to keep stepping here. */
+ if (stop_func_sal.pc == stop_pc)
+ {
+ /* We're there already. Just stop stepping now. */
+ ecs->event_thread->stop_step = 1;
+ print_stop_reason (END_STEPPING_RANGE, 0);
+ stop_stepping (ecs);
+ }
+ else
+ {
+ /* Else just reset the step range and keep going.
+ No step-resume breakpoint, they don't work for
+ epilogues, which can have multiple entry paths. */
+ ecs->event_thread->step_range_start = stop_func_sal.pc;
+ ecs->event_thread->step_range_end = stop_func_sal.end;
+ keep_going (ecs);
+ }
+ return;
+}
+
/* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
This is used to both functions and to skip over code. */
annotate_signal_string_end ();
ui_out_text (uiout, ".\n");
break;
+ case NO_HISTORY:
+ /* Reverse execution: target ran out of history info. */
+ ui_out_text (uiout, "\nNo more reverse-execution history.\n");
+ break;
default:
internal_error (__FILE__, __LINE__,
_("print_stop_reason: unrecognized enum value"));
}
\f
+/* User interface for reverse debugging:
+ Set exec-direction / show exec-direction commands
+ (returns error unless target implements to_set_exec_direction method). */
+
+enum exec_direction_kind execution_direction = EXEC_FORWARD;
+static const char exec_forward[] = "forward";
+static const char exec_reverse[] = "reverse";
+static const char *exec_direction = exec_forward;
+static const char *exec_direction_names[] = {
+ exec_forward,
+ exec_reverse,
+ NULL
+};
+
+static void
+set_exec_direction_func (char *args, int from_tty,
+ struct cmd_list_element *cmd)
+{
+ if (target_can_execute_reverse)
+ {
+ if (!strcmp (exec_direction, exec_forward))
+ execution_direction = EXEC_FORWARD;
+ else if (!strcmp (exec_direction, exec_reverse))
+ execution_direction = EXEC_REVERSE;
+ }
+}
+
+static void
+show_exec_direction_func (struct ui_file *out, int from_tty,
+ struct cmd_list_element *cmd, const char *value)
+{
+ switch (execution_direction) {
+ case EXEC_FORWARD:
+ fprintf_filtered (out, _("Forward.\n"));
+ break;
+ case EXEC_REVERSE:
+ fprintf_filtered (out, _("Reverse.\n"));
+ break;
+ case EXEC_ERROR:
+ default:
+ fprintf_filtered (out,
+ _("Forward (target `%s' does not support exec-direction).\n"),
+ target_shortname);
+ break;
+ }
+}
+
+/* User interface for non-stop mode. */
+
int non_stop = 0;
static int non_stop_1 = 0;
&maintenance_set_cmdlist,
&maintenance_show_cmdlist);
+ add_setshow_enum_cmd ("exec-direction", class_run, exec_direction_names,
+ &exec_direction, _("Set direction of execution.\n\
+Options are 'forward' or 'reverse'."),
+ _("Show direction of execution (forward/reverse)."),
+ _("Tells gdb whether to execute forward or backward."),
+ set_exec_direction_func, show_exec_direction_func,
+ &setlist, &showlist);
+
/* ptid initializations */
null_ptid = ptid_build (0, 0, 0);
minus_one_ptid = ptid_build (-1, 0, 0);
set_continue_thread (ptid);
buf = rs->buf;
- if (siggnal != TARGET_SIGNAL_0)
+ if (execution_direction == EXEC_REVERSE)
+ {
+ /* We don't pass signals to the target in reverse exec mode. */
+ if (info_verbose && siggnal != TARGET_SIGNAL_0)
+ warning (" - Can't pass signal %d to target in reverse: ignored.\n",
+ siggnal);
+ strcpy (buf, step ? "bs" : "bc");
+ }
+ else if (siggnal != TARGET_SIGNAL_0)
{
buf[0] = step ? 'S' : 'C';
buf[1] = tohex (((int) siggnal >> 4) & 0xf);
ptid_t event_ptid = null_ptid;
ULONGEST addr;
int solibs_changed = 0;
+ int replay_event = 0;
char *buf, *p;
status->kind = TARGET_WAITKIND_IGNORE;
solibs_changed = 1;
p = p_temp;
}
+ else if (strncmp (p, "replaylog", p1 - p) == 0)
+ {
+ /* NO_HISTORY event.
+ p1 will indicate "begin" or "end", but
+ it makes no difference for now, so ignore it. */
+ replay_event = 1;
+ p_temp = strchr (p1 + 1, ';');
+ if (p_temp)
+ p = p_temp;
+ }
else
{
/* Silently skip unknown optional info. */
case 'S': /* Old style status, just signal only. */
if (solibs_changed)
status->kind = TARGET_WAITKIND_LOADED;
+ else if (replay_event)
+ status->kind = TARGET_WAITKIND_NO_HISTORY;
else
{
status->kind = TARGET_WAITKIND_STOPPED;
help_list (remote_cmdlist, "remote ", -1, gdb_stdout);
}
+static int remote_target_can_reverse = 1;
+
+static int
+remote_can_execute_reverse (void)
+{
+ return remote_target_can_reverse;
+}
+
static void
init_remote_ops (void)
{
remote_ops.to_has_registers = 1;
remote_ops.to_has_execution = 1;
remote_ops.to_has_thread_control = tc_schedlock; /* can lock scheduler */
+ remote_ops.to_can_execute_reverse = remote_can_execute_reverse;
remote_ops.to_magic = OPS_MAGIC;
remote_ops.to_memory_map = remote_memory_map;
remote_ops.to_flash_erase = remote_flash_erase;
--- /dev/null
+/* Reverse execution and reverse debugging.
+
+ Copyright (C) 2006, 2007, 2008 Free Software Foundation, Inc.
+
+ 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 2 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, write to the Free Software
+ Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ Boston, MA 02110-1301, USA. */
+
+#include "defs.h"
+#include "gdb_string.h"
+#include "target.h"
+#include "top.h"
+#include "cli/cli-cmds.h"
+#include "cli/cli-decode.h"
+#include "inferior.h"
+
+/* User interface:
+ reverse-step, reverse-next etc. */
+
+static void exec_direction_default (void *notused)
+{
+ /* Return execution direction to default state. */
+ execution_direction = EXEC_FORWARD;
+}
+
+/* exec_reverse_once -- accepts an arbitrary gdb command (string),
+ and executes it with exec-direction set to 'reverse'.
+
+ Used to implement reverse-next etc. commands. */
+
+static void
+exec_reverse_once (char *cmd, char *args, int from_tty)
+{
+ char *reverse_command;
+ enum exec_direction_kind dir = execution_direction;
+ struct cleanup *old_chain;
+
+ if (dir == EXEC_ERROR)
+ error (_("Target %s does not support this command."), target_shortname);
+
+ if (dir == EXEC_REVERSE)
+ error (_("Already in reverse mode. Use '%s' or 'set exec-dir forward'."),
+ cmd);
+
+ if (!target_can_execute_reverse)
+ error (_("Target %s does not support this command."), target_shortname);
+
+ reverse_command = xstrprintf ("%s %s", cmd, args ? args : "");
+ old_chain = make_cleanup (exec_direction_default, NULL);
+ make_cleanup (xfree, reverse_command);
+ execution_direction = EXEC_REVERSE;
+ execute_command (reverse_command, from_tty);
+ do_cleanups (old_chain);
+}
+
+static void
+reverse_step (char *args, int from_tty)
+{
+ exec_reverse_once ("step", args, from_tty);
+}
+
+static void
+reverse_stepi (char *args, int from_tty)
+{
+ exec_reverse_once ("stepi", args, from_tty);
+}
+
+static void
+reverse_next (char *args, int from_tty)
+{
+ exec_reverse_once ("next", args, from_tty);
+}
+
+static void
+reverse_nexti (char *args, int from_tty)
+{
+ exec_reverse_once ("nexti", args, from_tty);
+}
+
+static void
+reverse_continue (char *args, int from_tty)
+{
+ exec_reverse_once ("continue", args, from_tty);
+}
+
+static void
+reverse_finish (char *args, int from_tty)
+{
+ exec_reverse_once ("finish", args, from_tty);
+}
+
+void
+_initialize_reverse (void)
+{
+ add_com ("reverse-step", class_run, reverse_step, _("\
+Step program backward until it reaches the beginning of another source line.\n\
+Argument N means do this N times (or till program stops for another reason).")
+ );
+ add_com_alias ("rs", "reverse-step", class_alias, 1);
+
+ add_com ("reverse-next", class_run, reverse_next, _("\
+Step program backward, proceeding through subroutine calls.\n\
+Like the \"reverse-step\" command as long as subroutine calls do not happen;\n\
+when they do, the call is treated as one instruction.\n\
+Argument N means do this N times (or till program stops for another reason).")
+ );
+ add_com_alias ("rn", "reverse-next", class_alias, 1);
+
+ add_com ("reverse-stepi", class_run, reverse_stepi, _("\
+Step backward exactly one instruction.\n\
+Argument N means do this N times (or till program stops for another reason).")
+ );
+ add_com_alias ("rsi", "reverse-stepi", class_alias, 0);
+
+ add_com ("reverse-nexti", class_run, reverse_nexti, _("\
+Step backward one instruction, but proceed through called subroutines.\n\
+Argument N means do this N times (or till program stops for another reason).")
+ );
+ add_com_alias ("rni", "reverse-nexti", class_alias, 0);
+
+ add_com ("reverse-continue", class_run, reverse_continue, _("\
+Continue program being debugged but run it in reverse.\n\
+If proceeding from breakpoint, a number N may be used as an argument,\n\
+which means to set the ignore count of that breakpoint to N - 1 (so that\n\
+the breakpoint won't break until the Nth time it is reached)."));
+ add_com_alias ("rc", "reverse-continue", class_alias, 0);
+
+ add_com ("reverse-finish", class_run, reverse_finish, _("\
+Execute backward until just before selected stack frame is called."));
+}
INHERIT (to_find_memory_regions, t);
INHERIT (to_make_corefile_notes, t);
INHERIT (to_get_thread_local_address, t);
+ INHERIT (to_can_execute_reverse, t);
/* Do not inherit to_read_description. */
/* Do not inherit to_search_memory. */
INHERIT (to_magic, t);
inferior, rather than being stuck in the remote_async_wait()
function. This way the event loop is responsive to other events,
like for instance the user typing. */
- TARGET_WAITKIND_IGNORE
+ TARGET_WAITKIND_IGNORE,
+
+ /* The target has run out of history information,
+ and cannot run backward any further. */
+ TARGET_WAITKIND_NO_HISTORY
};
struct target_waitstatus
const gdb_byte *pattern, ULONGEST pattern_len,
CORE_ADDR *found_addrp);
+ /* Can target execute in reverse? */
+ int (*to_can_execute_reverse) ();
+
int to_magic;
/* Need sub-structure for target machine related rather than comm related?
*/
#define target_watchpoint_addr_within_range(target, addr, start, length) \
(*target.to_watchpoint_addr_within_range) (target, addr, start, length)
+/* Target can execute in reverse? */
+#define target_can_execute_reverse \
+ (current_target.to_can_execute_reverse ? \
+ current_target.to_can_execute_reverse () : 0)
+
extern const struct target_desc *target_read_description (struct target_ops *);
/* Utility implementation of searching memory. */
projects / external / binutils.git / commitdiff