if (debug_infrun)
fprintf_unfiltered (gdb_stdlog,
- "infrun: resume (step=%d, signal=%d), "
+ "infrun: resume (step=%d, signal=%s), "
"trap_expected=%d, current thread [%s] at %s\n",
- step, sig, tp->control.trap_expected,
+ step, gdb_signal_to_symbol_string (sig),
+ tp->control.trap_expected,
target_pid_to_str (inferior_ptid),
paddress (gdbarch, pc));
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog,
- "infrun: proceed (addr=%s, signal=%d, step=%d)\n",
- paddress (gdbarch, addr), siggnal, step);
+ "infrun: proceed (addr=%s, signal=%s, step=%d)\n",
+ paddress (gdbarch, addr),
+ gdb_signal_to_symbol_string (siggnal), step);
if (non_stop)
/* In non-stop, each thread is handled individually. The context
static void stop_stepping (struct execution_control_state *ecs);
static void prepare_to_wait (struct execution_control_state *ecs);
static void keep_going (struct execution_control_state *ecs);
+static void process_event_stop_test (struct execution_control_state *ecs);
+static int switch_back_to_stepped_thread (struct execution_control_state *ecs);
/* Callback for iterate over threads. If the thread is stopped, but
the user/frontend doesn't know about that yet, go through
stop_pc, ecs->ptid, &ecs->ws);
sval = bpstat_explains_signal (ecs->event_thread->control.stop_bpstat,
- GDB_SIGNAL_TRAP);
+ GDB_SIGNAL_0);
ecs->random_signal = sval == BPSTAT_SIGNAL_NO;
if (!ecs->random_signal)
{
/* Catchpoint hit. */
- ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_TRAP;
return 0;
}
}
/* If no catchpoint triggered for this, then keep going. */
- ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
keep_going (ecs);
return 1;
}
-/* Clear the supplied execution_control_state's stop_func_* fields. */
-
-static void
-clear_stop_func (struct execution_control_state *ecs)
-{
- ecs->stop_func_filled_in = 0;
- ecs->stop_func_start = 0;
- ecs->stop_func_end = 0;
- ecs->stop_func_name = NULL;
-}
-
/* Lazily fill in the execution_control_state's stop_func_* fields. */
static void
struct gdbarch *gdbarch;
int stopped_by_watchpoint;
int stepped_after_stopped_by_watchpoint = 0;
- struct symtab_and_line stop_pc_sal;
enum stop_kind stop_soon;
if (ecs->ws.kind == TARGET_WAITKIND_IGNORE)
sval
= bpstat_explains_signal (ecs->event_thread->control.stop_bpstat,
- GDB_SIGNAL_TRAP);
+ GDB_SIGNAL_0);
ecs->random_signal = sval == BPSTAT_SIGNAL_NO;
if (!ecs->random_signal)
{
/* A catchpoint triggered. */
- ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_TRAP;
- goto process_event_stop_test;
+ process_event_stop_test (ecs);
+ return;
}
/* If requested, stop when the dynamic linker notifies
stop_stepping (ecs);
return;
}
- ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_TRAP;
- goto process_event_stop_test;
+ process_event_stop_test (ecs);
+ return;
case TARGET_WAITKIND_VFORK_DONE:
/* Done with the shared memory region. Re-insert breakpoints in
stop_pc, ecs->ptid, &ecs->ws);
ecs->random_signal
= (bpstat_explains_signal (ecs->event_thread->control.stop_bpstat,
- GDB_SIGNAL_TRAP)
+ GDB_SIGNAL_0)
== BPSTAT_SIGNAL_NO);
/* Note that this may be referenced from inside
keep_going (ecs);
return;
}
- ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_TRAP;
- goto process_event_stop_test;
+ process_event_stop_test (ecs);
+ return;
/* Be careful not to try to gather much state about a thread
that's in a syscall. It's frequently a losing proposition. */
fprintf_unfiltered (gdb_stdlog,
"infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
/* Getting the current syscall number. */
- if (handle_syscall_event (ecs) != 0)
- return;
- goto process_event_stop_test;
+ if (handle_syscall_event (ecs) == 0)
+ process_event_stop_test (ecs);
+ return;
/* Before examining the threads further, step this thread to
get it entirely out of the syscall. (We get notice of the
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog,
"infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
- if (handle_syscall_event (ecs) != 0)
- return;
- goto process_event_stop_test;
+ if (handle_syscall_event (ecs) == 0)
+ process_event_stop_test (ecs);
+ return;
case TARGET_WAITKIND_STOPPED:
if (debug_infrun)
remove_single_step_breakpoints ();
singlestep_breakpoints_inserted_p = 0;
- ecs->random_signal = 0;
ecs->event_thread->control.trap_expected = 0;
context_switch (saved_singlestep_ptid);
not see this breakpoint hit when stepping onto breakpoints. */
if (regular_breakpoint_inserted_here_p (aspace, stop_pc))
{
- ecs->random_signal = 0;
if (!breakpoint_thread_match (aspace, stop_pc, ecs->ptid))
thread_hop_needed = 1;
}
"trap for %s\n",
target_pid_to_str (ecs->ptid));
- ecs->random_signal = 0;
/* The call to in_thread_list is necessary because PTIDs sometimes
change when we go from single-threaded to multi-threaded. If
the singlestep_ptid is still in the list, assume that it is
return;
}
}
- else if (singlestep_breakpoints_inserted_p)
- {
- ecs->random_signal = 0;
- }
}
- else
- ecs->random_signal = 1;
/* See if something interesting happened to the non-current thread. If
so, then switch to that thread. */
return;
}
- clear_stop_func (ecs);
ecs->event_thread->stepping_over_breakpoint = 0;
bpstat_clear (&ecs->event_thread->control.stop_bpstat);
ecs->event_thread->control.stop_step = 0;
stop_print_frame = 1;
- ecs->random_signal = 0;
stopped_by_random_signal = 0;
/* Hide inlined functions starting here, unless we just performed stepi or
ecs->random_signal = (sval == BPSTAT_SIGNAL_NO);
if (sval == BPSTAT_SIGNAL_HIDE)
- ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_TRAP;
+ ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
}
-process_event_stop_test:
-
- /* Re-fetch current thread's frame in case we did a
- "goto process_event_stop_test" above. */
- frame = get_current_frame ();
- gdbarch = get_frame_arch (frame);
-
/* For the program's own signals, act according to
the signal handling tables. */
/* Signal not for debugging purposes. */
int printed = 0;
struct inferior *inf = find_inferior_pid (ptid_get_pid (ecs->ptid));
+ enum gdb_signal stop_signal = ecs->event_thread->suspend.stop_signal;
if (debug_infrun)
- fprintf_unfiltered (gdb_stdlog, "infrun: random signal %d\n",
- ecs->event_thread->suspend.stop_signal);
+ fprintf_unfiltered (gdb_stdlog, "infrun: random signal (%s)\n",
+ gdb_signal_to_symbol_string (stop_signal));
stopped_by_random_signal = 1;
(leaving the inferior at the step-resume-breakpoint without
actually executing it). Either way continue until the
breakpoint is really hit. */
- }
- else
- {
- /* Handle cases caused by hitting a breakpoint. */
-
- CORE_ADDR jmp_buf_pc;
- struct bpstat_what what;
-
- what = bpstat_what (ecs->event_thread->control.stop_bpstat);
-
- if (what.call_dummy)
- {
- stop_stack_dummy = what.call_dummy;
- }
-
- /* If we hit an internal event that triggers symbol changes, the
- current frame will be invalidated within bpstat_what (e.g.,
- if we hit an internal solib event). Re-fetch it. */
- frame = get_current_frame ();
- gdbarch = get_frame_arch (frame);
- switch (what.main_action)
+ if (!switch_back_to_stepped_thread (ecs))
{
- case BPSTAT_WHAT_SET_LONGJMP_RESUME:
- /* If we hit the breakpoint at longjmp while stepping, we
- install a momentary breakpoint at the target of the
- jmp_buf. */
-
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog,
- "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
-
- ecs->event_thread->stepping_over_breakpoint = 1;
-
- if (what.is_longjmp)
- {
- struct value *arg_value;
-
- /* If we set the longjmp breakpoint via a SystemTap
- probe, then use it to extract the arguments. The
- destination PC is the third argument to the
- probe. */
- arg_value = probe_safe_evaluate_at_pc (frame, 2);
- if (arg_value)
- jmp_buf_pc = value_as_address (arg_value);
- else if (!gdbarch_get_longjmp_target_p (gdbarch)
- || !gdbarch_get_longjmp_target (gdbarch,
- frame, &jmp_buf_pc))
- {
- if (debug_infrun)
- fprintf_unfiltered (gdb_stdlog,
- "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
- "(!gdbarch_get_longjmp_target)\n");
- keep_going (ecs);
- return;
- }
+ "infrun: random signal, keep going\n");
- /* Insert a breakpoint at resume address. */
- insert_longjmp_resume_breakpoint (gdbarch, jmp_buf_pc);
- }
- else
- check_exception_resume (ecs, frame);
keep_going (ecs);
- return;
+ }
+ return;
+ }
- case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
- {
- struct frame_info *init_frame;
+ process_event_stop_test (ecs);
+}
- /* There are several cases to consider.
+/* Come here when we've got some debug event / signal we can explain
+ (IOW, not a random signal), and test whether it should cause a
+ stop, or whether we should resume the inferior (transparently).
+ E.g., could be a breakpoint whose condition evaluates false; we
+ could be still stepping within the line; etc. */
- 1. The initiating frame no longer exists. In this case
- we must stop, because the exception or longjmp has gone
- too far.
+static void
+process_event_stop_test (struct execution_control_state *ecs)
+{
+ struct symtab_and_line stop_pc_sal;
+ struct frame_info *frame;
+ struct gdbarch *gdbarch;
+ CORE_ADDR jmp_buf_pc;
+ struct bpstat_what what;
- 2. The initiating frame exists, and is the same as the
- current frame. We stop, because the exception or
- longjmp has been caught.
+ /* Handle cases caused by hitting a breakpoint. */
- 3. The initiating frame exists and is different from
- the current frame. This means the exception or longjmp
- has been caught beneath the initiating frame, so keep
- going.
+ frame = get_current_frame ();
+ gdbarch = get_frame_arch (frame);
- 4. longjmp breakpoint has been placed just to protect
- against stale dummy frames and user is not interested
- in stopping around longjmps. */
+ what = bpstat_what (ecs->event_thread->control.stop_bpstat);
- if (debug_infrun)
- fprintf_unfiltered (gdb_stdlog,
- "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
+ if (what.call_dummy)
+ {
+ stop_stack_dummy = what.call_dummy;
+ }
- gdb_assert (ecs->event_thread->control.exception_resume_breakpoint
- != NULL);
- delete_exception_resume_breakpoint (ecs->event_thread);
+ /* If we hit an internal event that triggers symbol changes, the
+ current frame will be invalidated within bpstat_what (e.g., if we
+ hit an internal solib event). Re-fetch it. */
+ frame = get_current_frame ();
+ gdbarch = get_frame_arch (frame);
- if (what.is_longjmp)
- {
- check_longjmp_breakpoint_for_call_dummy (ecs->event_thread->num);
+ switch (what.main_action)
+ {
+ case BPSTAT_WHAT_SET_LONGJMP_RESUME:
+ /* If we hit the breakpoint at longjmp while stepping, we
+ install a momentary breakpoint at the target of the
+ jmp_buf. */
- if (!frame_id_p (ecs->event_thread->initiating_frame))
- {
- /* Case 4. */
- keep_going (ecs);
- return;
- }
- }
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
- init_frame = frame_find_by_id (ecs->event_thread->initiating_frame);
+ ecs->event_thread->stepping_over_breakpoint = 1;
- if (init_frame)
- {
- struct frame_id current_id
- = get_frame_id (get_current_frame ());
- if (frame_id_eq (current_id,
- ecs->event_thread->initiating_frame))
- {
- /* Case 2. Fall through. */
- }
- else
- {
- /* Case 3. */
- keep_going (ecs);
- return;
- }
- }
+ if (what.is_longjmp)
+ {
+ struct value *arg_value;
+
+ /* If we set the longjmp breakpoint via a SystemTap probe,
+ then use it to extract the arguments. The destination PC
+ is the third argument to the probe. */
+ arg_value = probe_safe_evaluate_at_pc (frame, 2);
+ if (arg_value)
+ jmp_buf_pc = value_as_address (arg_value);
+ else if (!gdbarch_get_longjmp_target_p (gdbarch)
+ || !gdbarch_get_longjmp_target (gdbarch,
+ frame, &jmp_buf_pc))
+ {
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
+ "(!gdbarch_get_longjmp_target)\n");
+ keep_going (ecs);
+ return;
+ }
- /* For Cases 1 and 2, remove the step-resume breakpoint,
- if it exists. */
- delete_step_resume_breakpoint (ecs->event_thread);
+ /* Insert a breakpoint at resume address. */
+ insert_longjmp_resume_breakpoint (gdbarch, jmp_buf_pc);
+ }
+ else
+ check_exception_resume (ecs, frame);
+ keep_going (ecs);
+ return;
- ecs->event_thread->control.stop_step = 1;
- print_end_stepping_range_reason ();
- stop_stepping (ecs);
- }
- return;
+ case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
+ {
+ struct frame_info *init_frame;
- case BPSTAT_WHAT_SINGLE:
- if (debug_infrun)
- fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_SINGLE\n");
- ecs->event_thread->stepping_over_breakpoint = 1;
- /* Still need to check other stuff, at least the case where
- we are stepping and step out of the right range. */
- break;
+ /* There are several cases to consider.
- case BPSTAT_WHAT_STEP_RESUME:
- if (debug_infrun)
- fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
+ 1. The initiating frame no longer exists. In this case we
+ must stop, because the exception or longjmp has gone too
+ far.
- delete_step_resume_breakpoint (ecs->event_thread);
- if (ecs->event_thread->control.proceed_to_finish
- && execution_direction == EXEC_REVERSE)
- {
- struct thread_info *tp = ecs->event_thread;
-
- /* We are finishing a function in reverse, and just hit
- the step-resume breakpoint at the start address of
- the function, and we're almost there -- just need to
- back up by one more single-step, which should take us
- back to the function call. */
- tp->control.step_range_start = tp->control.step_range_end = 1;
- keep_going (ecs);
- return;
- }
- fill_in_stop_func (gdbarch, ecs);
- 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;
+ 2. The initiating frame exists, and is the same as the
+ current frame. We stop, because the exception or longjmp
+ has been caught.
- case BPSTAT_WHAT_STOP_NOISY:
- if (debug_infrun)
- fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
- stop_print_frame = 1;
+ 3. The initiating frame exists and is different from the
+ current frame. This means the exception or longjmp has
+ been caught beneath the initiating frame, so keep going.
- /* We are about to nuke the step_resume_breakpointt via the
- cleanup chain, so no need to worry about it here. */
+ 4. longjmp breakpoint has been placed just to protect
+ against stale dummy frames and user is not interested in
+ stopping around longjmps. */
- stop_stepping (ecs);
- return;
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
- case BPSTAT_WHAT_STOP_SILENT:
- if (debug_infrun)
- fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
- stop_print_frame = 0;
+ gdb_assert (ecs->event_thread->control.exception_resume_breakpoint
+ != NULL);
+ delete_exception_resume_breakpoint (ecs->event_thread);
- /* We are about to nuke the step_resume_breakpoin via the
- cleanup chain, so no need to worry about it here. */
+ if (what.is_longjmp)
+ {
+ check_longjmp_breakpoint_for_call_dummy (ecs->event_thread->num);
- stop_stepping (ecs);
- return;
+ if (!frame_id_p (ecs->event_thread->initiating_frame))
+ {
+ /* Case 4. */
+ keep_going (ecs);
+ return;
+ }
+ }
- case BPSTAT_WHAT_HP_STEP_RESUME:
- if (debug_infrun)
- fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
+ init_frame = frame_find_by_id (ecs->event_thread->initiating_frame);
- delete_step_resume_breakpoint (ecs->event_thread);
- if (ecs->event_thread->step_after_step_resume_breakpoint)
- {
- /* Back when the step-resume breakpoint was inserted, we
- were trying to single-step off a breakpoint. Go back
- to doing that. */
- ecs->event_thread->step_after_step_resume_breakpoint = 0;
- ecs->event_thread->stepping_over_breakpoint = 1;
- keep_going (ecs);
- return;
- }
- break;
+ if (init_frame)
+ {
+ struct frame_id current_id
+ = get_frame_id (get_current_frame ());
+ if (frame_id_eq (current_id,
+ ecs->event_thread->initiating_frame))
+ {
+ /* Case 2. Fall through. */
+ }
+ else
+ {
+ /* Case 3. */
+ keep_going (ecs);
+ return;
+ }
+ }
- case BPSTAT_WHAT_KEEP_CHECKING:
- break;
- }
- }
+ /* For Cases 1 and 2, remove the step-resume breakpoint, if it
+ exists. */
+ delete_step_resume_breakpoint (ecs->event_thread);
- /* We come here if we hit a breakpoint but should not
- stop for it. Possibly we also were stepping
- and should stop for that. So fall through and
- test for stepping. But, if not stepping,
- do not stop. */
+ ecs->event_thread->control.stop_step = 1;
+ print_end_stepping_range_reason ();
+ stop_stepping (ecs);
+ }
+ return;
- /* In all-stop mode, if we're currently stepping but have stopped in
- some other thread, we need to switch back to the stepped thread. */
- if (!non_stop)
- {
- struct thread_info *tp;
+ case BPSTAT_WHAT_SINGLE:
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_SINGLE\n");
+ ecs->event_thread->stepping_over_breakpoint = 1;
+ /* Still need to check other stuff, at least the case where we
+ are stepping and step out of the right range. */
+ break;
- tp = iterate_over_threads (currently_stepping_or_nexting_callback,
- ecs->event_thread);
- if (tp)
+ case BPSTAT_WHAT_STEP_RESUME:
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
+
+ delete_step_resume_breakpoint (ecs->event_thread);
+ if (ecs->event_thread->control.proceed_to_finish
+ && execution_direction == EXEC_REVERSE)
{
- /* However, if the current thread is blocked on some internal
- breakpoint, and we simply need to step over that breakpoint
- to get it going again, do that first. */
- if ((ecs->event_thread->control.trap_expected
- && ecs->event_thread->suspend.stop_signal != GDB_SIGNAL_TRAP)
- || ecs->event_thread->stepping_over_breakpoint)
- {
- keep_going (ecs);
- return;
- }
+ struct thread_info *tp = ecs->event_thread;
+
+ /* We are finishing a function in reverse, and just hit the
+ step-resume breakpoint at the start address of the
+ function, and we're almost there -- just need to back up
+ by one more single-step, which should take us back to the
+ function call. */
+ tp->control.step_range_start = tp->control.step_range_end = 1;
+ keep_going (ecs);
+ return;
+ }
+ fill_in_stop_func (gdbarch, ecs);
+ 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;
- /* If the stepping thread exited, then don't try to switch
- back and resume it, which could fail in several different
- ways depending on the target. Instead, just keep going.
+ case BPSTAT_WHAT_STOP_NOISY:
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
+ stop_print_frame = 1;
- We can find a stepping dead thread in the thread list in
- two cases:
+ /* We are about to nuke the step_resume_breakpointt via the
+ cleanup chain, so no need to worry about it here. */
- - The target supports thread exit events, and when the
- target tries to delete the thread from the thread list,
- inferior_ptid pointed at the exiting thread. In such
- case, calling delete_thread does not really remove the
- thread from the list; instead, the thread is left listed,
- with 'exited' state.
+ stop_stepping (ecs);
+ return;
- - The target's debug interface does not support thread
- exit events, and so we have no idea whatsoever if the
- previously stepping thread is still alive. For that
- reason, we need to synchronously query the target
- now. */
- if (is_exited (tp->ptid)
- || !target_thread_alive (tp->ptid))
- {
- if (debug_infrun)
- fprintf_unfiltered (gdb_stdlog,
- "infrun: not switching back to "
- "stepped thread, it has vanished\n");
+ case BPSTAT_WHAT_STOP_SILENT:
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
+ stop_print_frame = 0;
- delete_thread (tp->ptid);
- keep_going (ecs);
- return;
- }
+ /* We are about to nuke the step_resume_breakpoin via the
+ cleanup chain, so no need to worry about it here. */
- /* Otherwise, we no longer expect a trap in the current thread.
- Clear the trap_expected flag before switching back -- this is
- what keep_going would do as well, if we called it. */
- ecs->event_thread->control.trap_expected = 0;
+ stop_stepping (ecs);
+ return;
- if (debug_infrun)
- fprintf_unfiltered (gdb_stdlog,
- "infrun: switching back to stepped thread\n");
+ case BPSTAT_WHAT_HP_STEP_RESUME:
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
- ecs->event_thread = tp;
- ecs->ptid = tp->ptid;
- context_switch (ecs->ptid);
+ delete_step_resume_breakpoint (ecs->event_thread);
+ if (ecs->event_thread->step_after_step_resume_breakpoint)
+ {
+ /* Back when the step-resume breakpoint was inserted, we
+ were trying to single-step off a breakpoint. Go back to
+ doing that. */
+ ecs->event_thread->step_after_step_resume_breakpoint = 0;
+ ecs->event_thread->stepping_over_breakpoint = 1;
keep_going (ecs);
return;
}
+ break;
+
+ case BPSTAT_WHAT_KEEP_CHECKING:
+ break;
}
+ /* We come here if we hit a breakpoint but should not stop for it.
+ Possibly we also were stepping and should stop for that. So fall
+ through and test for stepping. But, if not stepping, do not
+ stop. */
+
+ /* In all-stop mode, if we're currently stepping but have stopped in
+ some other thread, we need to switch back to the stepped thread. */
+ if (switch_back_to_stepped_thread (ecs))
+ return;
+
if (ecs->event_thread->control.step_resume_breakpoint)
{
if (debug_infrun)
keep_going (ecs);
}
+/* In all-stop mode, if we're currently stepping but have stopped in
+ some other thread, we may need to switch back to the stepped
+ thread. Returns true we set the inferior running, false if we left
+ it stopped (and the event needs further processing). */
+
+static int
+switch_back_to_stepped_thread (struct execution_control_state *ecs)
+{
+ if (!non_stop)
+ {
+ struct thread_info *tp;
+
+ tp = iterate_over_threads (currently_stepping_or_nexting_callback,
+ ecs->event_thread);
+ if (tp)
+ {
+ /* However, if the current thread is blocked on some internal
+ breakpoint, and we simply need to step over that breakpoint
+ to get it going again, do that first. */
+ if ((ecs->event_thread->control.trap_expected
+ && ecs->event_thread->suspend.stop_signal != GDB_SIGNAL_TRAP)
+ || ecs->event_thread->stepping_over_breakpoint)
+ {
+ keep_going (ecs);
+ return 1;
+ }
+
+ /* If the stepping thread exited, then don't try to switch
+ back and resume it, which could fail in several different
+ ways depending on the target. Instead, just keep going.
+
+ We can find a stepping dead thread in the thread list in
+ two cases:
+
+ - The target supports thread exit events, and when the
+ target tries to delete the thread from the thread list,
+ inferior_ptid pointed at the exiting thread. In such
+ case, calling delete_thread does not really remove the
+ thread from the list; instead, the thread is left listed,
+ with 'exited' state.
+
+ - The target's debug interface does not support thread
+ exit events, and so we have no idea whatsoever if the
+ previously stepping thread is still alive. For that
+ reason, we need to synchronously query the target
+ now. */
+ if (is_exited (tp->ptid)
+ || !target_thread_alive (tp->ptid))
+ {
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: not switching back to "
+ "stepped thread, it has vanished\n");
+
+ delete_thread (tp->ptid);
+ keep_going (ecs);
+ return 1;
+ }
+
+ /* Otherwise, we no longer expect a trap in the current thread.
+ Clear the trap_expected flag before switching back -- this is
+ what keep_going would do as well, if we called it. */
+ ecs->event_thread->control.trap_expected = 0;
+
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: switching back to stepped thread\n");
+
+ ecs->event_thread = tp;
+ ecs->ptid = tp->ptid;
+ context_switch (ecs->ptid);
+ keep_going (ecs);
+ return 1;
+ }
+ }
+ return 0;
+}
+
/* Is thread TP in the middle of single-stepping? */
static int
ecs->wait_some_more = 0;
}
-/* This function handles various cases where we need to continue
- waiting for the inferior. */
-/* (Used to be the keep_going: label in the old wait_for_inferior). */
+/* Called when we should continue running the inferior, because the
+ current event doesn't cause a user visible stop. This does the
+ resuming part; waiting for the next event is done elsewhere. */
static void
keep_going (struct execution_control_state *ecs)
ecs->event_thread->prev_pc
= regcache_read_pc (get_thread_regcache (ecs->ptid));
- /* If we did not do break;, it means we should keep running the
- inferior and not return to debugger. */
-
if (ecs->event_thread->control.trap_expected
&& ecs->event_thread->suspend.stop_signal != GDB_SIGNAL_TRAP)
{
- /* We took a signal (which we are supposed to pass through to
- the inferior, else we'd not get here) and we haven't yet
- gotten our trap. Simply continue. */
-
+ /* We haven't yet gotten our trap, and either: intercepted a
+ non-signal event (e.g., a fork); or took a signal which we
+ 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);
else
{
/* Either the trap was not expected, but we are continuing
- anyway (the user asked that this signal be passed to the
- child)
- -- or --
- The signal was SIGTRAP, e.g. it was our signal, but we
- decided we should resume from it.
+ anyway (if we got a signal, the user asked it be passed to
+ the child)
+ -- or --
+ We got our expected trap, but decided we should resume from
+ it.
- We're going to run this baby now!
+ We're going to run this baby now!
Note that insert_breakpoints won't try to re-insert
already inserted breakpoints. Therefore, we don't
care if breakpoints were already inserted, or not. */
-
+
if (ecs->event_thread->stepping_over_breakpoint)
{
struct regcache *thread_regcache = get_thread_regcache (ecs->ptid);
if (!use_displaced_stepping (get_regcache_arch (thread_regcache)))
- /* Since we can't do a displaced step, we have to remove
- the breakpoint while we step it. To keep things
- simple, we remove them all. */
- remove_breakpoints ();
+ {
+ /* Since we can't do a displaced step, we have to remove
+ the breakpoint while we step it. To keep things
+ simple, we remove them all. */
+ remove_breakpoints ();
+ }
}
else
{
volatile struct gdb_exception e;
- /* Stop stepping when inserting breakpoints
- has failed. */
+ /* Stop stepping if inserting breakpoints fails. */
TRY_CATCH (e, RETURN_MASK_ERROR)
{
insert_breakpoints ();
ecs->event_thread->control.trap_expected
= ecs->event_thread->stepping_over_breakpoint;
- /* Do not deliver SIGNAL_TRAP (except when the user explicitly
- specifies that such a signal should be delivered to the
- target program).
-
- Typically, this would occure when a user is debugging a
- target monitor on a simulator: the target monitor sets a
- breakpoint; the simulator encounters this break-point and
- halts the simulation handing control to GDB; GDB, noteing
- that the break-point isn't valid, returns control back to the
- simulator; the simulator then delivers the hardware
- equivalent of a SIGNAL_TRAP to the program being debugged. */
-
+ /* Do not deliver GDB_SIGNAL_TRAP (except when the user
+ explicitly specifies that such a signal should be delivered
+ to the target program). Typically, that would occur when a
+ user is debugging a target monitor on a simulator: the target
+ monitor sets a breakpoint; the simulator encounters this
+ breakpoint and halts the simulation handing control to GDB;
+ GDB, noting that the stop address doesn't map to any known
+ breakpoint, returns control back to the simulator; the
+ simulator then delivers the hardware equivalent of a
+ GDB_SIGNAL_TRAP to the program being debugged. */
if (ecs->event_thread->suspend.stop_signal == GDB_SIGNAL_TRAP
&& !signal_program[ecs->event_thread->suspend.stop_signal])
ecs->event_thread->suspend.stop_signal = GDB_SIGNAL_0;
projects / deliverable / binutils-gdb.git / blobdiff