#include "target-descriptions.h"
#include "target-dcache.h"
#include "terminal.h"
+#include "solist.h"
/* Prototypes for local functions */
static int currently_stepping (struct thread_info *tp);
-static void xdb_handle_command (char *args, int from_tty);
-
void _initialize_infrun (void);
void nullify_last_target_wait_ptid (void);
static void insert_longjmp_resume_breakpoint (struct gdbarch *, CORE_ADDR);
+static int maybe_software_singlestep (struct gdbarch *gdbarch, CORE_ADDR pc);
+
/* When set, stop the 'step' command if we enter a function which has
no line number information. The normal behavior is that we step
over such function. */
static struct cmd_list_element *stop_command;
-/* Function inferior was in as of last step command. */
-
-static struct symbol *step_start_function;
-
/* Nonzero if we want to give control to the user when we're notified
of shared library events by the dynamic linker. */
int stop_on_solib_events;
int stop_after_trap;
-/* Save register contents here when executing a "finish" command or are
- about to pop a stack dummy frame, if-and-only-if proceed_to_finish is set.
- Thus this contains the return value from the called function (assuming
- values are returned in a register). */
-
-struct regcache *stop_registers;
-
/* Nonzero after stop if current stack frame should be printed. */
static int stop_print_frame;
follow_fork_inferior (int follow_child, int detach_fork)
{
int has_vforked;
- int parent_pid, child_pid;
+ ptid_t parent_ptid, child_ptid;
has_vforked = (inferior_thread ()->pending_follow.kind
== TARGET_WAITKIND_VFORKED);
- parent_pid = ptid_get_lwp (inferior_ptid);
- if (parent_pid == 0)
- parent_pid = ptid_get_pid (inferior_ptid);
- child_pid
- = ptid_get_pid (inferior_thread ()->pending_follow.value.related_pid);
+ parent_ptid = inferior_ptid;
+ child_ptid = inferior_thread ()->pending_follow.value.related_pid;
if (has_vforked
&& !non_stop /* Non-stop always resumes both branches. */
if (info_verbose || debug_infrun)
{
+ /* Ensure that we have a process ptid. */
+ ptid_t process_ptid = pid_to_ptid (ptid_get_pid (child_ptid));
+
target_terminal_ours_for_output ();
fprintf_filtered (gdb_stdlog,
- _("Detaching after %s from "
- "child process %d.\n"),
+ _("Detaching after %s from child %s.\n"),
has_vforked ? "vfork" : "fork",
- child_pid);
+ target_pid_to_str (process_ptid));
}
}
else
struct cleanup *old_chain;
/* Add process to GDB's tables. */
- child_inf = add_inferior (child_pid);
+ child_inf = add_inferior (ptid_get_pid (child_ptid));
parent_inf = current_inferior ();
child_inf->attach_flag = parent_inf->attach_flag;
old_chain = save_inferior_ptid ();
save_current_program_space ();
- inferior_ptid = ptid_build (child_pid, child_pid, 0);
+ inferior_ptid = child_ptid;
add_thread (inferior_ptid);
child_inf->symfile_flags = SYMFILE_NO_READ;
{
target_terminal_ours_for_output ();
fprintf_filtered (gdb_stdlog,
- _("Attaching after process %d "
- "%s to child process %d.\n"),
- parent_pid,
+ _("Attaching after %s %s to child %s.\n"),
+ target_pid_to_str (parent_ptid),
has_vforked ? "vfork" : "fork",
- child_pid);
+ target_pid_to_str (child_ptid));
}
/* Add the new inferior first, so that the target_detach below
doesn't unpush the target. */
- child_inf = add_inferior (child_pid);
+ child_inf = add_inferior (ptid_get_pid (child_ptid));
parent_inf = current_inferior ();
child_inf->attach_flag = parent_inf->attach_flag;
{
if (info_verbose || debug_infrun)
{
+ /* Ensure that we have a process ptid. */
+ ptid_t process_ptid = pid_to_ptid (ptid_get_pid (child_ptid));
+
target_terminal_ours_for_output ();
fprintf_filtered (gdb_stdlog,
_("Detaching after fork from "
- "child process %d.\n"),
- child_pid);
+ "child %s.\n"),
+ target_pid_to_str (process_ptid));
}
target_detach (NULL, 0);
this new thread, before cloning the program space, and
informing the solib layer about this new process. */
- inferior_ptid = ptid_build (child_pid, child_pid, 0);
+ inferior_ptid = child_ptid;
add_thread (inferior_ptid);
/* If this is a vfork child, then the address-space is shared
switch_to_thread (thread->ptid);
clear_proceed_status (0);
- proceed ((CORE_ADDR) -1, GDB_SIGNAL_DEFAULT, 0);
+ proceed ((CORE_ADDR) -1, GDB_SIGNAL_DEFAULT);
}
return 0;
/* EXECD_PATHNAME is assumed to be non-NULL. */
static void
-follow_exec (ptid_t pid, char *execd_pathname)
+follow_exec (ptid_t ptid, char *execd_pathname)
{
- struct thread_info *th = inferior_thread ();
+ struct thread_info *th, *tmp;
struct inferior *inf = current_inferior ();
+ int pid = ptid_get_pid (ptid);
/* This is an exec event that we actually wish to pay attention to.
Refresh our symbol table to the newly exec'd program, remove any
mark_breakpoints_out ();
- update_breakpoints_after_exec ();
-
- /* If there was one, it's gone now. We cannot truly step-to-next
- statement through an exec(). */
+ /* The target reports the exec event to the main thread, even if
+ some other thread does the exec, and even if the main thread was
+ stopped or already gone. We may still have non-leader threads of
+ the process on our list. E.g., on targets that don't have thread
+ exit events (like remote); or on native Linux in non-stop mode if
+ there were only two threads in the inferior and the non-leader
+ one is the one that execs (and nothing forces an update of the
+ thread list up to here). When debugging remotely, it's best to
+ avoid extra traffic, when possible, so avoid syncing the thread
+ list with the target, and instead go ahead and delete all threads
+ of the process but one that reported the event. Note this must
+ be done before calling update_breakpoints_after_exec, as
+ otherwise clearing the threads' resources would reference stale
+ thread breakpoints -- it may have been one of these threads that
+ stepped across the exec. We could just clear their stepping
+ states, but as long as we're iterating, might as well delete
+ them. Deleting them now rather than at the next user-visible
+ stop provides a nicer sequence of events for user and MI
+ notifications. */
+ ALL_THREADS_SAFE (th, tmp)
+ if (ptid_get_pid (th->ptid) == pid && !ptid_equal (th->ptid, ptid))
+ delete_thread (th->ptid);
+
+ /* We also need to clear any left over stale state for the
+ leader/event thread. E.g., if there was any step-resume
+ breakpoint or similar, it's gone now. We cannot truly
+ step-to-next statement through an exec(). */
+ th = inferior_thread ();
th->control.step_resume_breakpoint = NULL;
th->control.exception_resume_breakpoint = NULL;
th->control.single_step_breakpoints = NULL;
th->control.step_range_start = 0;
th->control.step_range_end = 0;
- /* The target reports the exec event to the main thread, even if
- some other thread does the exec, and even if the main thread was
- already stopped --- if debugging in non-stop mode, it's possible
- the user had the main thread held stopped in the previous image
- --- release it now. This is the same behavior as step-over-exec
- with scheduler-locking on in all-stop mode. */
+ /* The user may have had the main thread held stopped in the
+ previous image (e.g., schedlock on, or non-stop). Release
+ it now. */
th->stop_requested = 0;
+ update_breakpoints_after_exec ();
+
/* What is this a.out's name? */
printf_unfiltered (_("%s is executing new program: %s\n"),
target_pid_to_str (inferior_ptid),
breakpoint_init_inferior (inf_execd);
- if (gdb_sysroot && *gdb_sysroot)
+ if (gdb_sysroot != NULL && *gdb_sysroot != '\0')
{
- char *name = alloca (strlen (gdb_sysroot)
- + strlen (execd_pathname)
- + 1);
+ char *name = exec_file_find (execd_pathname, NULL);
- strcpy (name, gdb_sysroot);
- strcat (name, execd_pathname);
- execd_pathname = name;
+ execd_pathname = alloca (strlen (name) + 1);
+ strcpy (execd_pathname, name);
+ xfree (name);
}
/* Reset the shared library package. This ensures that we get a
return NULL;
}
+/* Return true if process PID has a thread doing a displaced step. */
+
+static int
+displaced_step_in_progress (int pid)
+{
+ struct displaced_step_inferior_state *displaced;
+
+ displaced = get_displaced_stepping_state (pid);
+ if (displaced != NULL && !ptid_equal (displaced->step_ptid, null_ptid))
+ return 1;
+
+ return 0;
+}
+
/* Add a new displaced stepping state for process PID to the displaced
stepping state list, or return a pointer to an already existing
entry, if it already exists. Never returns NULL. */
displaced_step_restore (displaced, displaced->step_ptid);
+ /* Fixup may need to read memory/registers. Switch to the thread
+ that we're fixing up. Also, target_stopped_by_watchpoint checks
+ the current thread. */
+ switch_to_thread (event_ptid);
+
/* Did the instruction complete successfully? */
- if (signal == GDB_SIGNAL_TRAP)
+ if (signal == GDB_SIGNAL_TRAP
+ && !(target_stopped_by_watchpoint ()
+ && (gdbarch_have_nonsteppable_watchpoint (displaced->step_gdbarch)
+ || target_have_steppable_watchpoint)))
{
- /* Fixup may need to read memory/registers. Switch to the
- thread that we're fixing up. */
- switch_to_thread (event_ptid);
-
/* Fix up the resulting state. */
gdbarch_displaced_step_fixup (displaced->step_gdbarch,
displaced->step_closure,
regcache = get_thread_regcache (ptid);
actual_pc = regcache_read_pc (regcache);
aspace = get_regcache_aspace (regcache);
+ gdbarch = get_regcache_arch (regcache);
if (breakpoint_here_p (aspace, actual_pc))
{
displaced_step_prepare (ptid);
- gdbarch = get_regcache_arch (regcache);
-
if (debug_displaced)
{
CORE_ADDR actual_pc = regcache_read_pc (regcache);
/* Go back to what we were trying to do. */
step = currently_stepping (tp);
+ if (step)
+ step = maybe_software_singlestep (gdbarch, actual_pc);
+
if (debug_displaced)
fprintf_unfiltered (gdb_stdlog,
"displaced: breakpoint is gone: %s, step(%d)\n",
return hw_step;
}
+/* See infrun.h. */
+
ptid_t
user_visible_resume_ptid (int step)
{
- /* By default, resume all threads of all processes. */
- ptid_t resume_ptid = RESUME_ALL;
-
- /* Maybe resume only all threads of the current process. */
- if (!sched_multi && target_supports_multi_process ())
- {
- resume_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
- }
+ ptid_t resume_ptid;
- /* Maybe resume a single thread after all. */
if (non_stop)
{
/* With non-stop mode on, threads are always handled
else if ((scheduler_mode == schedlock_on)
|| (scheduler_mode == schedlock_step && step))
{
- /* User-settable 'scheduler' mode requires solo thread resume. */
+ /* User-settable 'scheduler' mode requires solo thread
+ resume. */
resume_ptid = inferior_ptid;
}
+ else if (!sched_multi && target_supports_multi_process ())
+ {
+ /* Resume all threads of the current process (and none of other
+ processes). */
+ resume_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
+ }
+ else
+ {
+ /* Resume all threads of all processes. */
+ resume_ptid = RESUME_ALL;
+ }
- /* We may actually resume fewer threads at first, e.g., if a thread
- is stopped at a breakpoint that needs stepping-off, but that
- should not be visible to the user/frontend, and neither should
- the frontend/user be allowed to proceed any of the threads that
- happen to be stopped for internal run control handling, if a
- previous command wanted them resumed. */
return resume_ptid;
}
+/* Wrapper for target_resume, that handles infrun-specific
+ bookkeeping. */
+
+static void
+do_target_resume (ptid_t resume_ptid, int step, enum gdb_signal sig)
+{
+ struct thread_info *tp = inferior_thread ();
+
+ /* Install inferior's terminal modes. */
+ target_terminal_inferior ();
+
+ /* Avoid confusing the next resume, if the next stop/resume
+ happens to apply to another thread. */
+ tp->suspend.stop_signal = GDB_SIGNAL_0;
+
+ /* Advise target which signals may be handled silently.
+
+ If we have removed breakpoints because we are stepping over one
+ in-line (in any thread), we need to receive all signals to avoid
+ accidentally skipping a breakpoint during execution of a signal
+ handler.
+
+ Likewise if we're displaced stepping, otherwise a trap for a
+ breakpoint in a signal handler might be confused with the
+ displaced step finishing. We don't make the displaced_step_fixup
+ step distinguish the cases instead, because:
+
+ - a backtrace while stopped in the signal handler would show the
+ scratch pad as frame older than the signal handler, instead of
+ the real mainline code.
+
+ - when the thread is later resumed, the signal handler would
+ return to the scratch pad area, which would no longer be
+ valid. */
+ if (step_over_info_valid_p ()
+ || displaced_step_in_progress (ptid_get_pid (tp->ptid)))
+ target_pass_signals (0, NULL);
+ else
+ target_pass_signals ((int) GDB_SIGNAL_LAST, signal_pass);
+
+ target_resume (resume_ptid, step, sig);
+}
+
/* Resume the inferior, but allow a QUIT. This is useful if the user
wants to interrupt some lengthy single-stepping operation
(for child processes, the SIGINT goes to the inferior, and so
we get a SIGINT random_signal, but for remote debugging and perhaps
other targets, that's not true).
- STEP nonzero if we should step (zero to continue instead).
SIG is the signal to give the inferior (zero for none). */
void
-resume (int step, enum gdb_signal sig)
+resume (enum gdb_signal sig)
{
struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
struct regcache *regcache = get_current_regcache ();
CORE_ADDR pc = regcache_read_pc (regcache);
struct address_space *aspace = get_regcache_aspace (regcache);
ptid_t resume_ptid;
- /* From here on, this represents the caller's step vs continue
- request, while STEP represents what we'll actually request the
- target to do. STEP can decay from a step to a continue, if e.g.,
- we need to implement single-stepping with breakpoints (software
- single-step). When deciding whether "set scheduler-locking step"
- applies, it's the callers intention that counts. */
- const int entry_step = step;
+ /* This represents the user's step vs continue request. When
+ deciding whether "set scheduler-locking step" applies, it's the
+ user's intention that counts. */
+ const int user_step = tp->control.stepping_command;
+ /* This represents what we'll actually request the target to do.
+ This can decay from a step to a continue, if e.g., we need to
+ implement single-stepping with breakpoints (software
+ single-step). */
+ int step;
tp->stepped_breakpoint = 0;
QUIT;
+ /* Depends on stepped_breakpoint. */
+ step = currently_stepping (tp);
+
if (current_inferior ()->waiting_for_vfork_done)
{
/* Don't try to single-step a vfork parent that is waiting for
reported to handle_inferior_event. Set a breakpoint
at the current PC, and run to it. Don't update
prev_pc, because if we end in
- switch_back_to_stepping, we want the "expected thread
- advanced also" branch to be taken. IOW, we don't
- want this thread to step further from PC
+ switch_back_to_stepped_thread, we want the "expected
+ thread advanced also" branch to be taken. IOW, we
+ don't want this thread to step further from PC
(overstep). */
+ gdb_assert (!step_over_info_valid_p ());
insert_single_step_breakpoint (gdbarch, aspace, pc);
insert_breakpoints ();
- tp->suspend.stop_signal = GDB_SIGNAL_0;
- /* We're continuing with all breakpoints inserted. It's
- safe to let the target bypass signals. */
- target_pass_signals ((int) GDB_SIGNAL_LAST, signal_pass);
- /* ... and safe to let other threads run, according to
- schedlock. */
- resume_ptid = user_visible_resume_ptid (entry_step);
- target_resume (resume_ptid, 0, GDB_SIGNAL_0);
+ resume_ptid = user_visible_resume_ptid (user_step);
+ do_target_resume (resume_ptid, 0, GDB_SIGNAL_0);
discard_cleanups (old_cleanups);
return;
}
step software breakpoint. */
if (use_displaced_stepping (gdbarch)
&& tp->control.trap_expected
+ && !step_over_info_valid_p ()
&& sig == GDB_SIGNAL_0
&& !current_inferior ()->waiting_for_vfork_done)
{
Unless we're calling an inferior function, as in that
case we pretend the inferior doesn't run at all. */
if (!tp->control.in_infcall)
- set_running (user_visible_resume_ptid (entry_step), 1);
+ set_running (user_visible_resume_ptid (user_step), 1);
discard_cleanups (old_cleanups);
return;
}
/* Decide the set of threads to ask the target to resume. Start
by assuming everything will be resumed, than narrow the set
by applying increasingly restricting conditions. */
- resume_ptid = user_visible_resume_ptid (entry_step);
+ resume_ptid = user_visible_resume_ptid (user_step);
/* Even if RESUME_PTID is a wildcard, and we end up resuming less
(e.g., we might need to step over a breakpoint), from the
if (debug_displaced
&& use_displaced_stepping (gdbarch)
- && tp->control.trap_expected)
+ && tp->control.trap_expected
+ && !step_over_info_valid_p ())
{
- struct regcache *resume_regcache = get_thread_regcache (resume_ptid);
+ struct regcache *resume_regcache = get_thread_regcache (tp->ptid);
struct gdbarch *resume_gdbarch = get_regcache_arch (resume_regcache);
CORE_ADDR actual_pc = regcache_read_pc (resume_regcache);
gdb_byte buf[4];
gdb_assert (pc_in_thread_step_range (pc, tp));
}
- /* Install inferior's terminal modes. */
- target_terminal_inferior ();
-
- /* Avoid confusing the next resume, if the next stop/resume
- happens to apply to another thread. */
- tp->suspend.stop_signal = GDB_SIGNAL_0;
-
- /* Advise target which signals may be handled silently. If we have
- removed breakpoints because we are stepping over one (in any
- thread), we need to receive all signals to avoid accidentally
- skipping a breakpoint during execution of a signal handler. */
- if (step_over_info_valid_p ())
- target_pass_signals (0, NULL);
- else
- target_pass_signals ((int) GDB_SIGNAL_LAST, signal_pass);
-
- target_resume (resume_ptid, step, sig);
-
+ do_target_resume (resume_ptid, step, sig);
discard_cleanups (old_cleanups);
}
\f
tp->control.step_frame_id = null_frame_id;
tp->control.step_stack_frame_id = null_frame_id;
tp->control.step_over_calls = STEP_OVER_UNDEBUGGABLE;
+ tp->control.step_start_function = NULL;
tp->stop_requested = 0;
tp->control.stop_step = 0;
tp->control.proceed_to_finish = 0;
tp->control.command_interp = NULL;
+ tp->control.stepping_command = 0;
/* Discard any remaining commands or status from previous stop. */
bpstat_clear (&tp->control.stop_bpstat);
clear_step_over_info ();
observer_notify_about_to_proceed ();
-
- if (stop_registers)
- {
- regcache_xfree (stop_registers);
- stop_registers = NULL;
- }
}
/* Returns true if TP is still stopped at a breakpoint that needs
we're about to do a step/next-like command to a thread. */
static int
-schedlock_applies (int step)
+schedlock_applies (struct thread_info *tp)
{
return (scheduler_mode == schedlock_on
|| (scheduler_mode == schedlock_step
- && step));
+ && tp->control.stepping_command));
}
/* Look a thread other than EXCEPT that has previously reported a
breakpoint event, and thus needs a step-over in order to make
- progress. Returns NULL is none is found. STEP indicates whether
- we're about to step the current thread, in order to decide whether
- "set scheduler-locking step" applies. */
+ progress. Returns NULL is none is found. */
static struct thread_info *
-find_thread_needs_step_over (int step, struct thread_info *except)
+find_thread_needs_step_over (struct thread_info *except)
{
struct thread_info *tp, *current;
/* If scheduler locking applies, we can avoid iterating over all
threads. */
- if (schedlock_applies (step))
+ if (schedlock_applies (except))
{
if (except != current
&& thread_still_needs_step_over (current))
You should call clear_proceed_status before calling proceed. */
void
-proceed (CORE_ADDR addr, enum gdb_signal siggnal, int step)
+proceed (CORE_ADDR addr, enum gdb_signal siggnal)
{
struct regcache *regcache;
struct gdbarch *gdbarch;
pc = regcache_read_pc (regcache);
tp = inferior_thread ();
- if (step > 0)
- step_start_function = find_pc_function (pc);
- if (step < 0)
- stop_after_trap = 1;
-
/* Fill in with reasonable starting values. */
init_thread_stepping_state (tp);
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog,
- "infrun: proceed (addr=%s, signal=%s, step=%d)\n",
+ "infrun: proceed (addr=%s, signal=%s)\n",
paddress (gdbarch, addr),
- gdb_signal_to_symbol_string (siggnal), step);
+ gdb_signal_to_symbol_string (siggnal));
if (non_stop)
/* In non-stop, each thread is handled individually. The context
Look for a thread other than the current (TP) that reported a
breakpoint hit and hasn't been resumed yet since. */
- step_over = find_thread_needs_step_over (step, tp);
+ step_over = find_thread_needs_step_over (tp);
if (step_over != NULL)
{
if (debug_infrun)
target_pid_to_str (step_over->ptid));
/* Store the prev_pc for the stepping thread too, needed by
- switch_back_to_stepping thread. */
+ switch_back_to_stepped_thread. */
tp->prev_pc = regcache_read_pc (get_current_regcache ());
switch_to_thread (step_over->ptid);
tp = step_over;
tp->prev_pc = regcache_read_pc (get_current_regcache ());
/* Resume inferior. */
- resume (tp->control.trap_expected || step || bpstat_should_step (),
- tp->suspend.stop_signal);
+ resume (tp->suspend.stop_signal);
/* Wait for it to stop (if not standalone)
and in any case decode why it stopped, and act accordingly. */
is set. */
fprintf_unfiltered (tmp_stream,
- "infrun: target_wait (%d", ptid_get_pid (waiton_ptid));
+ "infrun: target_wait (%d.%ld.%ld",
+ ptid_get_pid (waiton_ptid),
+ ptid_get_lwp (waiton_ptid),
+ ptid_get_tid (waiton_ptid));
if (ptid_get_pid (waiton_ptid) != -1)
fprintf_unfiltered (tmp_stream,
" [%s]", target_pid_to_str (waiton_ptid));
fprintf_unfiltered (tmp_stream, ", status) =\n");
fprintf_unfiltered (tmp_stream,
- "infrun: %d [%s],\n",
+ "infrun: %d.%ld.%ld [%s],\n",
ptid_get_pid (result_ptid),
+ ptid_get_lwp (result_ptid),
+ ptid_get_tid (result_ptid),
target_pid_to_str (result_ptid));
fprintf_unfiltered (tmp_stream,
"infrun: %s\n",
wait_for_inferior (void)
{
struct cleanup *old_cleanups;
+ struct cleanup *thread_state_chain;
if (debug_infrun)
fprintf_unfiltered
= make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup,
NULL);
+ /* If an error happens while handling the event, propagate GDB's
+ knowledge of the executing state to the frontend/user running
+ state. */
+ thread_state_chain = make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
+
while (1)
{
struct execution_control_state ecss;
struct execution_control_state *ecs = &ecss;
- struct cleanup *old_chain;
ptid_t waiton_ptid = minus_one_ptid;
memset (ecs, 0, sizeof (*ecs));
if (debug_infrun)
print_target_wait_results (waiton_ptid, ecs->ptid, &ecs->ws);
- /* If an error happens while handling the event, propagate GDB's
- knowledge of the executing state to the frontend/user running
- state. */
- old_chain = make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
-
/* Now figure out what to do with the result of the result. */
handle_inferior_event (ecs);
- /* No error, don't finish the state yet. */
- discard_cleanups (old_chain);
-
if (!ecs->wait_some_more)
break;
}
+ /* No error, don't finish the state yet. */
+ discard_cleanups (thread_state_chain);
+
do_cleanups (old_cleanups);
}
if (execution_direction == EXEC_REVERSE)
return;
+ /* If the target can tell whether the thread hit a SW breakpoint,
+ trust it. Targets that can tell also adjust the PC
+ themselves. */
+ if (target_supports_stopped_by_sw_breakpoint ())
+ return;
+
+ /* Note that relying on whether a breakpoint is planted in memory to
+ determine this can fail. E.g,. the breakpoint could have been
+ removed since. Or the thread could have been told to step an
+ instruction the size of a breakpoint instruction, and only
+ _after_ was a breakpoint inserted at its address. */
+
/* If this target does not decrement the PC after breakpoints, then
we have nothing to do. */
regcache = get_thread_regcache (ecs->ptid);
gdbarch = get_regcache_arch (regcache);
- decr_pc = target_decr_pc_after_break (gdbarch);
+ decr_pc = gdbarch_decr_pc_after_break (gdbarch);
if (decr_pc == 0)
return;
breakpoint would be. */
breakpoint_pc = regcache_read_pc (regcache) - decr_pc;
+ /* If the target can't tell whether a software breakpoint triggered,
+ fallback to figuring it out based on breakpoints we think were
+ inserted in the target, and on whether the thread was stepped or
+ continued. */
+
/* Check whether there actually is a software breakpoint inserted at
that location.
removed a breakpoint, but stop events for that breakpoint were
already queued and arrive later. To suppress those spurious
SIGTRAPs, we keep a list of such breakpoint locations for a bit,
- and retire them after a number of stop events are reported. */
+ and retire them after a number of stop events are reported. Note
+ this is an heuristic and can thus get confused. The real fix is
+ to get the "stopped by SW BP and needs adjustment" info out of
+ the target/kernel (and thus never reach here; see above). */
if (software_breakpoint_inserted_here_p (aspace, breakpoint_pc)
|| (non_stop && moribund_breakpoint_here_p (aspace, breakpoint_pc)))
{
The SIGTRAP can be due to a completed hardware single-step only if
- we didn't insert software single-step breakpoints
- - the thread to be examined is still the current thread
- this thread is currently being stepped
If any of these events did not occur, we must have stopped due
we also need to back up to the breakpoint address. */
if (thread_has_single_step_breakpoints_set (ecs->event_thread)
- || !ptid_equal (ecs->ptid, inferior_ptid)
|| !currently_stepping (ecs->event_thread)
|| (ecs->event_thread->stepped_breakpoint
&& ecs->event_thread->prev_pc == breakpoint_pc))
once). */
static void
-handle_inferior_event (struct execution_control_state *ecs)
+handle_inferior_event_1 (struct execution_control_state *ecs)
{
enum stop_kind stop_soon;
addresses. Make sure new breakpoints are inserted. */
if (stop_soon == NO_STOP_QUIETLY)
insert_breakpoints ();
- resume (0, GDB_SIGNAL_0);
+ resume (GDB_SIGNAL_0);
prepare_to_wait (ecs);
return;
}
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SPURIOUS\n");
if (!ptid_equal (ecs->ptid, inferior_ptid))
context_switch (ecs->ptid);
- resume (0, GDB_SIGNAL_0);
+ resume (GDB_SIGNAL_0);
prepare_to_wait (ecs);
return;
}
}
+/* A wrapper around handle_inferior_event_1, which also makes sure
+ that all temporary struct value objects that were created during
+ the handling of the event get deleted at the end. */
+
+static void
+handle_inferior_event (struct execution_control_state *ecs)
+{
+ struct value *mark = value_mark ();
+
+ handle_inferior_event_1 (ecs);
+ /* Purge all temporary values created during the event handling,
+ as it could be a long time before we return to the command level
+ where such values would otherwise be purged. */
+ value_free_to_mark (mark);
+}
+
/* Come here when the program has stopped with a signal. */
static void
= !bpstat_explains_signal (ecs->event_thread->control.stop_bpstat,
ecs->event_thread->suspend.stop_signal);
+ /* Maybe this was a trap for a software breakpoint that has since
+ been removed. */
+ if (random_signal && target_stopped_by_sw_breakpoint ())
+ {
+ if (program_breakpoint_here_p (gdbarch, stop_pc))
+ {
+ struct regcache *regcache;
+ int decr_pc;
+
+ /* Re-adjust PC to what the program would see if GDB was not
+ debugging it. */
+ regcache = get_thread_regcache (ecs->event_thread->ptid);
+ decr_pc = gdbarch_decr_pc_after_break (gdbarch);
+ if (decr_pc != 0)
+ {
+ struct cleanup *old_cleanups = make_cleanup (null_cleanup, NULL);
+
+ if (record_full_is_used ())
+ record_full_gdb_operation_disable_set ();
+
+ regcache_write_pc (regcache, stop_pc + decr_pc);
+
+ do_cleanups (old_cleanups);
+ }
+ }
+ else
+ {
+ /* A delayed software breakpoint event. Ignore the trap. */
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: delayed software breakpoint "
+ "trap, ignoring\n");
+ random_signal = 0;
+ }
+ }
+
+ /* Maybe this was a trap for a hardware breakpoint/watchpoint that
+ has since been removed. */
+ if (random_signal && target_stopped_by_hw_breakpoint ())
+ {
+ /* A delayed hardware breakpoint event. Ignore the trap. */
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: delayed hardware breakpoint/watchpoint "
+ "trap, ignoring\n");
+ random_signal = 0;
+ }
+
/* If not, perhaps stepping/nexting can. */
if (random_signal)
random_signal = !(ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
struct breakpoint *sr_bp
= ecs->event_thread->control.step_resume_breakpoint;
- if (sr_bp->loc->permanent
+ if (sr_bp != NULL
+ && sr_bp->loc->permanent
&& sr_bp->type == bp_hp_step_resume
&& sr_bp->loc->address == ecs->event_thread->prev_pc)
{
ecs->event_thread->control.step_stack_frame_id)
&& (!frame_id_eq (ecs->event_thread->control.step_stack_frame_id,
outer_frame_id)
- || step_start_function != find_pc_function (stop_pc))))
+ || (ecs->event_thread->control.step_start_function
+ != find_pc_function (stop_pc)))))
{
CORE_ADDR real_stop_pc;
current thread is stepping. If some other thread not the
event thread is stepping, then it must be that scheduler
locking is not in effect. */
- if (schedlock_applies (0))
+ if (schedlock_applies (ecs->event_thread))
return 0;
/* Look for the stepping/nexting thread, and check if any other
stepping, then scheduler locking can't be in effect,
otherwise we wouldn't have resumed the current event
thread in the first place. */
- gdb_assert (!schedlock_applies (currently_stepping (tp)));
+ gdb_assert (!schedlock_applies (tp));
stepping_thread = tp;
}
if (stop_pc != tp->prev_pc)
{
+ ptid_t resume_ptid;
+
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog,
"infrun: expected thread advanced also\n");
insert_single_step_breakpoint (get_frame_arch (frame),
get_frame_address_space (frame),
stop_pc);
- ecs->event_thread->control.trap_expected = 1;
- resume (0, GDB_SIGNAL_0);
+ resume_ptid = user_visible_resume_ptid (tp->control.stepping_command);
+ do_target_resume (resume_ptid,
+ currently_stepping (tp), GDB_SIGNAL_0);
prepare_to_wait (ecs);
}
else
struct frame_info *frame,
struct symbol *sym)
{
- volatile struct gdb_exception e;
-
- /* We want to ignore errors here. */
- TRY_CATCH (e, RETURN_MASK_ERROR)
+ TRY
{
struct symbol *vsym;
struct value *value;
inferior_thread ()->control.exception_resume_breakpoint = bp;
}
}
+ CATCH (e, RETURN_MASK_ERROR)
+ {
+ /* We want to ignore errors here. */
+ }
+ END_CATCH
}
/* A helper for check_exception_resume that sets an
check_exception_resume (struct execution_control_state *ecs,
struct frame_info *frame)
{
- volatile struct gdb_exception e;
struct bound_probe probe;
struct symbol *func;
if (!func)
return;
- TRY_CATCH (e, RETURN_MASK_ERROR)
+ TRY
{
const struct block *b;
struct block_iterator iter;
}
}
}
+ CATCH (e, RETURN_MASK_ERROR)
+ {
+ }
+ END_CATCH
}
static void
are supposed to pass through to the inferior. Simply
continue. */
discard_cleanups (old_cleanups);
- resume (currently_stepping (ecs->event_thread),
- ecs->event_thread->suspend.stop_signal);
+ resume (ecs->event_thread->suspend.stop_signal);
}
else
{
- volatile struct gdb_exception e;
struct regcache *regcache = get_current_regcache ();
int remove_bp;
int remove_wps;
remove_wps = (ecs->event_thread->stepping_over_watchpoint
&& !target_have_steppable_watchpoint);
- if (remove_bp && !use_displaced_stepping (get_regcache_arch (regcache)))
+ /* We can't use displaced stepping if we need to step past a
+ watchpoint. The instruction copied to the scratch pad would
+ still trigger the watchpoint. */
+ if (remove_bp
+ && (remove_wps
+ || !use_displaced_stepping (get_regcache_arch (regcache))))
{
set_step_over_info (get_regcache_aspace (regcache),
regcache_read_pc (regcache), remove_wps);
clear_step_over_info ();
/* Stop stepping if inserting breakpoints fails. */
- TRY_CATCH (e, RETURN_MASK_ERROR)
+ TRY
{
insert_breakpoints ();
}
- if (e.reason < 0)
+ CATCH (e, RETURN_MASK_ERROR)
{
exception_print (gdb_stderr, e);
stop_waiting (ecs);
+ discard_cleanups (old_cleanups);
return;
}
+ END_CATCH
ecs->event_thread->control.trap_expected = (remove_bp || remove_wps);
ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
discard_cleanups (old_cleanups);
- resume (currently_stepping (ecs->event_thread),
- ecs->event_thread->suspend.stop_signal);
+ resume (ecs->event_thread->suspend.stop_signal);
}
prepare_to_wait (ecs);
if (tp->control.stop_step
&& frame_id_eq (tp->control.step_frame_id,
get_frame_id (get_current_frame ()))
- && step_start_function == find_pc_function (stop_pc))
+ && tp->control.step_start_function == find_pc_function (stop_pc))
{
/* Finished step, just print source line. */
source_flag = SRC_LINE;
print_stop_event (&last);
}
- /* Save the function value return registers, if we care.
- We might be about to restore their previous contents. */
- if (inferior_thread ()->control.proceed_to_finish
- && execution_direction != EXEC_REVERSE)
- {
- /* This should not be necessary. */
- if (stop_registers)
- regcache_xfree (stop_registers);
-
- /* NB: The copy goes through to the target picking up the value of
- all the registers. */
- stop_registers = regcache_dup (get_current_regcache ());
- }
-
if (stop_stack_dummy == STOP_STACK_DUMMY)
{
/* Pop the empty frame that contains the stack dummy.
return return_val;
}
-static void
-xdb_handle_command (char *args, int from_tty)
-{
- char **argv;
- struct cleanup *old_chain;
-
- if (args == NULL)
- error_no_arg (_("xdb command"));
-
- /* Break the command line up into args. */
-
- argv = gdb_buildargv (args);
- old_chain = make_cleanup_freeargv (argv);
- if (argv[1] != (char *) NULL)
- {
- char *argBuf;
- int bufLen;
-
- bufLen = strlen (argv[0]) + 20;
- argBuf = (char *) xmalloc (bufLen);
- if (argBuf)
- {
- int validFlag = 1;
- enum gdb_signal oursig;
-
- oursig = gdb_signal_from_name (argv[0]);
- memset (argBuf, 0, bufLen);
- if (strcmp (argv[1], "Q") == 0)
- sprintf (argBuf, "%s %s", argv[0], "noprint");
- else
- {
- if (strcmp (argv[1], "s") == 0)
- {
- if (!signal_stop[oursig])
- sprintf (argBuf, "%s %s", argv[0], "stop");
- else
- sprintf (argBuf, "%s %s", argv[0], "nostop");
- }
- else if (strcmp (argv[1], "i") == 0)
- {
- if (!signal_program[oursig])
- sprintf (argBuf, "%s %s", argv[0], "pass");
- else
- sprintf (argBuf, "%s %s", argv[0], "nopass");
- }
- else if (strcmp (argv[1], "r") == 0)
- {
- if (!signal_print[oursig])
- sprintf (argBuf, "%s %s", argv[0], "print");
- else
- sprintf (argBuf, "%s %s", argv[0], "noprint");
- }
- else
- validFlag = 0;
- }
- if (validFlag)
- handle_command (argBuf, from_tty);
- else
- printf_filtered (_("Invalid signal handling flag.\n"));
- if (argBuf)
- xfree (argBuf);
- }
- }
- do_cleanups (old_chain);
-}
-
enum gdb_signal
gdb_signal_from_command (int num)
{
all signals cumulatively specified."));
set_cmd_completer (c, handle_completer);
- if (xdb_commands)
- {
- add_com ("lz", class_info, signals_info, _("\
-What debugger does when program gets various signals.\n\
-Specify a signal as argument to print info on that signal only."));
- add_com ("z", class_run, xdb_handle_command, _("\
-Specify how to handle a signal.\n\
-Args are signals and actions to apply to those signals.\n\
-Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
-from 1-15 are allowed for compatibility with old versions of GDB.\n\
-Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
-The special arg \"all\" is recognized to mean all signals except those\n\
-used by the debugger, typically SIGTRAP and SIGINT.\n\
-Recognized actions include \"s\" (toggles between stop and nostop),\n\
-\"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
-nopass), \"Q\" (noprint)\n\
-Stop means reenter debugger if this signal happens (implies print).\n\
-Print means print a message if this signal happens.\n\
-Pass means let program see this signal; otherwise program doesn't know.\n\
-Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
-Pass and Stop may be combined."));
- }
-
if (!dbx_commands)
stop_command = add_cmd ("stop", class_obscure,
not_just_help_class_command, _("\
Show mode for locking scheduler during execution."), _("\
off == no locking (threads may preempt at any time)\n\
on == full locking (no thread except the current thread may run)\n\
-step == scheduler locked during every single-step operation.\n\
- In this mode, no other thread may run during a step command.\n\
- Other threads may run while stepping over a function call ('next')."),
+step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
+ In this mode, other threads may run during other commands."),
set_schedlock_func, /* traps on target vector */
show_scheduler_mode,
&setlist, &showlist);