1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2018 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
27 #include "breakpoint.h"
31 #include "cli/cli-script.h"
33 #include "gdbthread.h"
41 #include "observable.h"
45 #include "dictionary.h"
47 #include "mi/mi-common.h"
48 #include "event-top.h"
50 #include "record-full.h"
51 #include "inline-frame.h"
53 #include "tracepoint.h"
54 #include "continuations.h"
59 #include "completer.h"
60 #include "target-descriptions.h"
61 #include "target-dcache.h"
64 #include "event-loop.h"
65 #include "thread-fsm.h"
66 #include "common/enum-flags.h"
67 #include "progspace-and-thread.h"
68 #include "common/gdb_optional.h"
69 #include "arch-utils.h"
71 /* Prototypes for local functions */
73 static void sig_print_info (enum gdb_signal
);
75 static void sig_print_header (void);
77 static int follow_fork (void);
79 static int follow_fork_inferior (int follow_child
, int detach_fork
);
81 static void follow_inferior_reset_breakpoints (void);
83 static int currently_stepping (struct thread_info
*tp
);
85 void nullify_last_target_wait_ptid (void);
87 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*);
89 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
91 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
93 static int maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
);
95 /* Asynchronous signal handler registered as event loop source for
96 when we have pending events ready to be passed to the core. */
97 static struct async_event_handler
*infrun_async_inferior_event_token
;
99 /* Stores whether infrun_async was previously enabled or disabled.
100 Starts off as -1, indicating "never enabled/disabled". */
101 static int infrun_is_async
= -1;
106 infrun_async (int enable
)
108 if (infrun_is_async
!= enable
)
110 infrun_is_async
= enable
;
113 fprintf_unfiltered (gdb_stdlog
,
114 "infrun: infrun_async(%d)\n",
118 mark_async_event_handler (infrun_async_inferior_event_token
);
120 clear_async_event_handler (infrun_async_inferior_event_token
);
127 mark_infrun_async_event_handler (void)
129 mark_async_event_handler (infrun_async_inferior_event_token
);
132 /* When set, stop the 'step' command if we enter a function which has
133 no line number information. The normal behavior is that we step
134 over such function. */
135 int step_stop_if_no_debug
= 0;
137 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
138 struct cmd_list_element
*c
, const char *value
)
140 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
143 /* proceed and normal_stop use this to notify the user when the
144 inferior stopped in a different thread than it had been running
147 static ptid_t previous_inferior_ptid
;
149 /* If set (default for legacy reasons), when following a fork, GDB
150 will detach from one of the fork branches, child or parent.
151 Exactly which branch is detached depends on 'set follow-fork-mode'
154 static int detach_fork
= 1;
156 int debug_displaced
= 0;
158 show_debug_displaced (struct ui_file
*file
, int from_tty
,
159 struct cmd_list_element
*c
, const char *value
)
161 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
164 unsigned int debug_infrun
= 0;
166 show_debug_infrun (struct ui_file
*file
, int from_tty
,
167 struct cmd_list_element
*c
, const char *value
)
169 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
173 /* Support for disabling address space randomization. */
175 int disable_randomization
= 1;
178 show_disable_randomization (struct ui_file
*file
, int from_tty
,
179 struct cmd_list_element
*c
, const char *value
)
181 if (target_supports_disable_randomization ())
182 fprintf_filtered (file
,
183 _("Disabling randomization of debuggee's "
184 "virtual address space is %s.\n"),
187 fputs_filtered (_("Disabling randomization of debuggee's "
188 "virtual address space is unsupported on\n"
189 "this platform.\n"), file
);
193 set_disable_randomization (const char *args
, int from_tty
,
194 struct cmd_list_element
*c
)
196 if (!target_supports_disable_randomization ())
197 error (_("Disabling randomization of debuggee's "
198 "virtual address space is unsupported on\n"
202 /* User interface for non-stop mode. */
205 static int non_stop_1
= 0;
208 set_non_stop (const char *args
, int from_tty
,
209 struct cmd_list_element
*c
)
211 if (target_has_execution
)
213 non_stop_1
= non_stop
;
214 error (_("Cannot change this setting while the inferior is running."));
217 non_stop
= non_stop_1
;
221 show_non_stop (struct ui_file
*file
, int from_tty
,
222 struct cmd_list_element
*c
, const char *value
)
224 fprintf_filtered (file
,
225 _("Controlling the inferior in non-stop mode is %s.\n"),
229 /* "Observer mode" is somewhat like a more extreme version of
230 non-stop, in which all GDB operations that might affect the
231 target's execution have been disabled. */
233 int observer_mode
= 0;
234 static int observer_mode_1
= 0;
237 set_observer_mode (const char *args
, int from_tty
,
238 struct cmd_list_element
*c
)
240 if (target_has_execution
)
242 observer_mode_1
= observer_mode
;
243 error (_("Cannot change this setting while the inferior is running."));
246 observer_mode
= observer_mode_1
;
248 may_write_registers
= !observer_mode
;
249 may_write_memory
= !observer_mode
;
250 may_insert_breakpoints
= !observer_mode
;
251 may_insert_tracepoints
= !observer_mode
;
252 /* We can insert fast tracepoints in or out of observer mode,
253 but enable them if we're going into this mode. */
255 may_insert_fast_tracepoints
= 1;
256 may_stop
= !observer_mode
;
257 update_target_permissions ();
259 /* Going *into* observer mode we must force non-stop, then
260 going out we leave it that way. */
263 pagination_enabled
= 0;
264 non_stop
= non_stop_1
= 1;
268 printf_filtered (_("Observer mode is now %s.\n"),
269 (observer_mode
? "on" : "off"));
273 show_observer_mode (struct ui_file
*file
, int from_tty
,
274 struct cmd_list_element
*c
, const char *value
)
276 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
279 /* This updates the value of observer mode based on changes in
280 permissions. Note that we are deliberately ignoring the values of
281 may-write-registers and may-write-memory, since the user may have
282 reason to enable these during a session, for instance to turn on a
283 debugging-related global. */
286 update_observer_mode (void)
290 newval
= (!may_insert_breakpoints
291 && !may_insert_tracepoints
292 && may_insert_fast_tracepoints
296 /* Let the user know if things change. */
297 if (newval
!= observer_mode
)
298 printf_filtered (_("Observer mode is now %s.\n"),
299 (newval
? "on" : "off"));
301 observer_mode
= observer_mode_1
= newval
;
304 /* Tables of how to react to signals; the user sets them. */
306 static unsigned char *signal_stop
;
307 static unsigned char *signal_print
;
308 static unsigned char *signal_program
;
310 /* Table of signals that are registered with "catch signal". A
311 non-zero entry indicates that the signal is caught by some "catch
312 signal" command. This has size GDB_SIGNAL_LAST, to accommodate all
314 static unsigned char *signal_catch
;
316 /* Table of signals that the target may silently handle.
317 This is automatically determined from the flags above,
318 and simply cached here. */
319 static unsigned char *signal_pass
;
321 #define SET_SIGS(nsigs,sigs,flags) \
323 int signum = (nsigs); \
324 while (signum-- > 0) \
325 if ((sigs)[signum]) \
326 (flags)[signum] = 1; \
329 #define UNSET_SIGS(nsigs,sigs,flags) \
331 int signum = (nsigs); \
332 while (signum-- > 0) \
333 if ((sigs)[signum]) \
334 (flags)[signum] = 0; \
337 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
338 this function is to avoid exporting `signal_program'. */
341 update_signals_program_target (void)
343 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
346 /* Value to pass to target_resume() to cause all threads to resume. */
348 #define RESUME_ALL minus_one_ptid
350 /* Command list pointer for the "stop" placeholder. */
352 static struct cmd_list_element
*stop_command
;
354 /* Nonzero if we want to give control to the user when we're notified
355 of shared library events by the dynamic linker. */
356 int stop_on_solib_events
;
358 /* Enable or disable optional shared library event breakpoints
359 as appropriate when the above flag is changed. */
362 set_stop_on_solib_events (const char *args
,
363 int from_tty
, struct cmd_list_element
*c
)
365 update_solib_breakpoints ();
369 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
370 struct cmd_list_element
*c
, const char *value
)
372 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
376 /* Nonzero after stop if current stack frame should be printed. */
378 static int stop_print_frame
;
380 /* This is a cached copy of the pid/waitstatus of the last event
381 returned by target_wait()/deprecated_target_wait_hook(). This
382 information is returned by get_last_target_status(). */
383 static ptid_t target_last_wait_ptid
;
384 static struct target_waitstatus target_last_waitstatus
;
386 static void context_switch (ptid_t ptid
);
388 void init_thread_stepping_state (struct thread_info
*tss
);
390 static const char follow_fork_mode_child
[] = "child";
391 static const char follow_fork_mode_parent
[] = "parent";
393 static const char *const follow_fork_mode_kind_names
[] = {
394 follow_fork_mode_child
,
395 follow_fork_mode_parent
,
399 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
401 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
402 struct cmd_list_element
*c
, const char *value
)
404 fprintf_filtered (file
,
405 _("Debugger response to a program "
406 "call of fork or vfork is \"%s\".\n"),
411 /* Handle changes to the inferior list based on the type of fork,
412 which process is being followed, and whether the other process
413 should be detached. On entry inferior_ptid must be the ptid of
414 the fork parent. At return inferior_ptid is the ptid of the
415 followed inferior. */
418 follow_fork_inferior (int follow_child
, int detach_fork
)
421 ptid_t parent_ptid
, child_ptid
;
423 has_vforked
= (inferior_thread ()->pending_follow
.kind
424 == TARGET_WAITKIND_VFORKED
);
425 parent_ptid
= inferior_ptid
;
426 child_ptid
= inferior_thread ()->pending_follow
.value
.related_pid
;
429 && !non_stop
/* Non-stop always resumes both branches. */
430 && current_ui
->prompt_state
== PROMPT_BLOCKED
431 && !(follow_child
|| detach_fork
|| sched_multi
))
433 /* The parent stays blocked inside the vfork syscall until the
434 child execs or exits. If we don't let the child run, then
435 the parent stays blocked. If we're telling the parent to run
436 in the foreground, the user will not be able to ctrl-c to get
437 back the terminal, effectively hanging the debug session. */
438 fprintf_filtered (gdb_stderr
, _("\
439 Can not resume the parent process over vfork in the foreground while\n\
440 holding the child stopped. Try \"set detach-on-fork\" or \
441 \"set schedule-multiple\".\n"));
442 /* FIXME output string > 80 columns. */
448 /* Detach new forked process? */
451 /* Before detaching from the child, remove all breakpoints
452 from it. If we forked, then this has already been taken
453 care of by infrun.c. If we vforked however, any
454 breakpoint inserted in the parent is visible in the
455 child, even those added while stopped in a vfork
456 catchpoint. This will remove the breakpoints from the
457 parent also, but they'll be reinserted below. */
460 /* Keep breakpoints list in sync. */
461 remove_breakpoints_pid (ptid_get_pid (inferior_ptid
));
464 if (info_verbose
|| debug_infrun
)
466 /* Ensure that we have a process ptid. */
467 ptid_t process_ptid
= pid_to_ptid (ptid_get_pid (child_ptid
));
469 target_terminal::ours_for_output ();
470 fprintf_filtered (gdb_stdlog
,
471 _("Detaching after %s from child %s.\n"),
472 has_vforked
? "vfork" : "fork",
473 target_pid_to_str (process_ptid
));
478 struct inferior
*parent_inf
, *child_inf
;
480 /* Add process to GDB's tables. */
481 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
483 parent_inf
= current_inferior ();
484 child_inf
->attach_flag
= parent_inf
->attach_flag
;
485 copy_terminal_info (child_inf
, parent_inf
);
486 child_inf
->gdbarch
= parent_inf
->gdbarch
;
487 copy_inferior_target_desc_info (child_inf
, parent_inf
);
489 scoped_restore_current_pspace_and_thread restore_pspace_thread
;
491 inferior_ptid
= child_ptid
;
492 add_thread (inferior_ptid
);
493 set_current_inferior (child_inf
);
494 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
496 /* If this is a vfork child, then the address-space is
497 shared with the parent. */
500 child_inf
->pspace
= parent_inf
->pspace
;
501 child_inf
->aspace
= parent_inf
->aspace
;
503 /* The parent will be frozen until the child is done
504 with the shared region. Keep track of the
506 child_inf
->vfork_parent
= parent_inf
;
507 child_inf
->pending_detach
= 0;
508 parent_inf
->vfork_child
= child_inf
;
509 parent_inf
->pending_detach
= 0;
513 child_inf
->aspace
= new_address_space ();
514 child_inf
->pspace
= new program_space (child_inf
->aspace
);
515 child_inf
->removable
= 1;
516 set_current_program_space (child_inf
->pspace
);
517 clone_program_space (child_inf
->pspace
, parent_inf
->pspace
);
519 /* Let the shared library layer (e.g., solib-svr4) learn
520 about this new process, relocate the cloned exec, pull
521 in shared libraries, and install the solib event
522 breakpoint. If a "cloned-VM" event was propagated
523 better throughout the core, this wouldn't be
525 solib_create_inferior_hook (0);
531 struct inferior
*parent_inf
;
533 parent_inf
= current_inferior ();
535 /* If we detached from the child, then we have to be careful
536 to not insert breakpoints in the parent until the child
537 is done with the shared memory region. However, if we're
538 staying attached to the child, then we can and should
539 insert breakpoints, so that we can debug it. A
540 subsequent child exec or exit is enough to know when does
541 the child stops using the parent's address space. */
542 parent_inf
->waiting_for_vfork_done
= detach_fork
;
543 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
548 /* Follow the child. */
549 struct inferior
*parent_inf
, *child_inf
;
550 struct program_space
*parent_pspace
;
552 if (info_verbose
|| debug_infrun
)
554 target_terminal::ours_for_output ();
555 fprintf_filtered (gdb_stdlog
,
556 _("Attaching after %s %s to child %s.\n"),
557 target_pid_to_str (parent_ptid
),
558 has_vforked
? "vfork" : "fork",
559 target_pid_to_str (child_ptid
));
562 /* Add the new inferior first, so that the target_detach below
563 doesn't unpush the target. */
565 child_inf
= add_inferior (ptid_get_pid (child_ptid
));
567 parent_inf
= current_inferior ();
568 child_inf
->attach_flag
= parent_inf
->attach_flag
;
569 copy_terminal_info (child_inf
, parent_inf
);
570 child_inf
->gdbarch
= parent_inf
->gdbarch
;
571 copy_inferior_target_desc_info (child_inf
, parent_inf
);
573 parent_pspace
= parent_inf
->pspace
;
575 /* If we're vforking, we want to hold on to the parent until the
576 child exits or execs. At child exec or exit time we can
577 remove the old breakpoints from the parent and detach or
578 resume debugging it. Otherwise, detach the parent now; we'll
579 want to reuse it's program/address spaces, but we can't set
580 them to the child before removing breakpoints from the
581 parent, otherwise, the breakpoints module could decide to
582 remove breakpoints from the wrong process (since they'd be
583 assigned to the same address space). */
587 gdb_assert (child_inf
->vfork_parent
== NULL
);
588 gdb_assert (parent_inf
->vfork_child
== NULL
);
589 child_inf
->vfork_parent
= parent_inf
;
590 child_inf
->pending_detach
= 0;
591 parent_inf
->vfork_child
= child_inf
;
592 parent_inf
->pending_detach
= detach_fork
;
593 parent_inf
->waiting_for_vfork_done
= 0;
595 else if (detach_fork
)
597 if (info_verbose
|| debug_infrun
)
599 /* Ensure that we have a process ptid. */
600 ptid_t process_ptid
= pid_to_ptid (ptid_get_pid (child_ptid
));
602 target_terminal::ours_for_output ();
603 fprintf_filtered (gdb_stdlog
,
604 _("Detaching after fork from "
606 target_pid_to_str (process_ptid
));
609 target_detach (parent_inf
, 0);
612 /* Note that the detach above makes PARENT_INF dangling. */
614 /* Add the child thread to the appropriate lists, and switch to
615 this new thread, before cloning the program space, and
616 informing the solib layer about this new process. */
618 inferior_ptid
= child_ptid
;
619 add_thread (inferior_ptid
);
620 set_current_inferior (child_inf
);
622 /* If this is a vfork child, then the address-space is shared
623 with the parent. If we detached from the parent, then we can
624 reuse the parent's program/address spaces. */
625 if (has_vforked
|| detach_fork
)
627 child_inf
->pspace
= parent_pspace
;
628 child_inf
->aspace
= child_inf
->pspace
->aspace
;
632 child_inf
->aspace
= new_address_space ();
633 child_inf
->pspace
= new program_space (child_inf
->aspace
);
634 child_inf
->removable
= 1;
635 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
636 set_current_program_space (child_inf
->pspace
);
637 clone_program_space (child_inf
->pspace
, parent_pspace
);
639 /* Let the shared library layer (e.g., solib-svr4) learn
640 about this new process, relocate the cloned exec, pull in
641 shared libraries, and install the solib event breakpoint.
642 If a "cloned-VM" event was propagated better throughout
643 the core, this wouldn't be required. */
644 solib_create_inferior_hook (0);
648 return target_follow_fork (follow_child
, detach_fork
);
651 /* Tell the target to follow the fork we're stopped at. Returns true
652 if the inferior should be resumed; false, if the target for some
653 reason decided it's best not to resume. */
658 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
659 int should_resume
= 1;
660 struct thread_info
*tp
;
662 /* Copy user stepping state to the new inferior thread. FIXME: the
663 followed fork child thread should have a copy of most of the
664 parent thread structure's run control related fields, not just these.
665 Initialized to avoid "may be used uninitialized" warnings from gcc. */
666 struct breakpoint
*step_resume_breakpoint
= NULL
;
667 struct breakpoint
*exception_resume_breakpoint
= NULL
;
668 CORE_ADDR step_range_start
= 0;
669 CORE_ADDR step_range_end
= 0;
670 struct frame_id step_frame_id
= { 0 };
671 struct thread_fsm
*thread_fsm
= NULL
;
676 struct target_waitstatus wait_status
;
678 /* Get the last target status returned by target_wait(). */
679 get_last_target_status (&wait_ptid
, &wait_status
);
681 /* If not stopped at a fork event, then there's nothing else to
683 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
684 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
687 /* Check if we switched over from WAIT_PTID, since the event was
689 if (!ptid_equal (wait_ptid
, minus_one_ptid
)
690 && !ptid_equal (inferior_ptid
, wait_ptid
))
692 /* We did. Switch back to WAIT_PTID thread, to tell the
693 target to follow it (in either direction). We'll
694 afterwards refuse to resume, and inform the user what
696 switch_to_thread (wait_ptid
);
701 tp
= inferior_thread ();
703 /* If there were any forks/vforks that were caught and are now to be
704 followed, then do so now. */
705 switch (tp
->pending_follow
.kind
)
707 case TARGET_WAITKIND_FORKED
:
708 case TARGET_WAITKIND_VFORKED
:
710 ptid_t parent
, child
;
712 /* If the user did a next/step, etc, over a fork call,
713 preserve the stepping state in the fork child. */
714 if (follow_child
&& should_resume
)
716 step_resume_breakpoint
= clone_momentary_breakpoint
717 (tp
->control
.step_resume_breakpoint
);
718 step_range_start
= tp
->control
.step_range_start
;
719 step_range_end
= tp
->control
.step_range_end
;
720 step_frame_id
= tp
->control
.step_frame_id
;
721 exception_resume_breakpoint
722 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
723 thread_fsm
= tp
->thread_fsm
;
725 /* For now, delete the parent's sr breakpoint, otherwise,
726 parent/child sr breakpoints are considered duplicates,
727 and the child version will not be installed. Remove
728 this when the breakpoints module becomes aware of
729 inferiors and address spaces. */
730 delete_step_resume_breakpoint (tp
);
731 tp
->control
.step_range_start
= 0;
732 tp
->control
.step_range_end
= 0;
733 tp
->control
.step_frame_id
= null_frame_id
;
734 delete_exception_resume_breakpoint (tp
);
735 tp
->thread_fsm
= NULL
;
738 parent
= inferior_ptid
;
739 child
= tp
->pending_follow
.value
.related_pid
;
741 /* Set up inferior(s) as specified by the caller, and tell the
742 target to do whatever is necessary to follow either parent
744 if (follow_fork_inferior (follow_child
, detach_fork
))
746 /* Target refused to follow, or there's some other reason
747 we shouldn't resume. */
752 /* This pending follow fork event is now handled, one way
753 or another. The previous selected thread may be gone
754 from the lists by now, but if it is still around, need
755 to clear the pending follow request. */
756 tp
= find_thread_ptid (parent
);
758 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
760 /* This makes sure we don't try to apply the "Switched
761 over from WAIT_PID" logic above. */
762 nullify_last_target_wait_ptid ();
764 /* If we followed the child, switch to it... */
767 switch_to_thread (child
);
769 /* ... and preserve the stepping state, in case the
770 user was stepping over the fork call. */
773 tp
= inferior_thread ();
774 tp
->control
.step_resume_breakpoint
775 = step_resume_breakpoint
;
776 tp
->control
.step_range_start
= step_range_start
;
777 tp
->control
.step_range_end
= step_range_end
;
778 tp
->control
.step_frame_id
= step_frame_id
;
779 tp
->control
.exception_resume_breakpoint
780 = exception_resume_breakpoint
;
781 tp
->thread_fsm
= thread_fsm
;
785 /* If we get here, it was because we're trying to
786 resume from a fork catchpoint, but, the user
787 has switched threads away from the thread that
788 forked. In that case, the resume command
789 issued is most likely not applicable to the
790 child, so just warn, and refuse to resume. */
791 warning (_("Not resuming: switched threads "
792 "before following fork child."));
795 /* Reset breakpoints in the child as appropriate. */
796 follow_inferior_reset_breakpoints ();
799 switch_to_thread (parent
);
803 case TARGET_WAITKIND_SPURIOUS
:
804 /* Nothing to follow. */
807 internal_error (__FILE__
, __LINE__
,
808 "Unexpected pending_follow.kind %d\n",
809 tp
->pending_follow
.kind
);
813 return should_resume
;
817 follow_inferior_reset_breakpoints (void)
819 struct thread_info
*tp
= inferior_thread ();
821 /* Was there a step_resume breakpoint? (There was if the user
822 did a "next" at the fork() call.) If so, explicitly reset its
823 thread number. Cloned step_resume breakpoints are disabled on
824 creation, so enable it here now that it is associated with the
827 step_resumes are a form of bp that are made to be per-thread.
828 Since we created the step_resume bp when the parent process
829 was being debugged, and now are switching to the child process,
830 from the breakpoint package's viewpoint, that's a switch of
831 "threads". We must update the bp's notion of which thread
832 it is for, or it'll be ignored when it triggers. */
834 if (tp
->control
.step_resume_breakpoint
)
836 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
837 tp
->control
.step_resume_breakpoint
->loc
->enabled
= 1;
840 /* Treat exception_resume breakpoints like step_resume breakpoints. */
841 if (tp
->control
.exception_resume_breakpoint
)
843 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
844 tp
->control
.exception_resume_breakpoint
->loc
->enabled
= 1;
847 /* Reinsert all breakpoints in the child. The user may have set
848 breakpoints after catching the fork, in which case those
849 were never set in the child, but only in the parent. This makes
850 sure the inserted breakpoints match the breakpoint list. */
852 breakpoint_re_set ();
853 insert_breakpoints ();
856 /* The child has exited or execed: resume threads of the parent the
857 user wanted to be executing. */
860 proceed_after_vfork_done (struct thread_info
*thread
,
863 int pid
= * (int *) arg
;
865 if (ptid_get_pid (thread
->ptid
) == pid
866 && is_running (thread
->ptid
)
867 && !is_executing (thread
->ptid
)
868 && !thread
->stop_requested
869 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
872 fprintf_unfiltered (gdb_stdlog
,
873 "infrun: resuming vfork parent thread %s\n",
874 target_pid_to_str (thread
->ptid
));
876 switch_to_thread (thread
->ptid
);
877 clear_proceed_status (0);
878 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
);
884 /* Save/restore inferior_ptid, current program space and current
885 inferior. Only use this if the current context points at an exited
886 inferior (and therefore there's no current thread to save). */
887 class scoped_restore_exited_inferior
890 scoped_restore_exited_inferior ()
891 : m_saved_ptid (&inferior_ptid
)
895 scoped_restore_tmpl
<ptid_t
> m_saved_ptid
;
896 scoped_restore_current_program_space m_pspace
;
897 scoped_restore_current_inferior m_inferior
;
900 /* Called whenever we notice an exec or exit event, to handle
901 detaching or resuming a vfork parent. */
904 handle_vfork_child_exec_or_exit (int exec
)
906 struct inferior
*inf
= current_inferior ();
908 if (inf
->vfork_parent
)
910 int resume_parent
= -1;
912 /* This exec or exit marks the end of the shared memory region
913 between the parent and the child. If the user wanted to
914 detach from the parent, now is the time. */
916 if (inf
->vfork_parent
->pending_detach
)
918 struct thread_info
*tp
;
919 struct program_space
*pspace
;
920 struct address_space
*aspace
;
922 /* follow-fork child, detach-on-fork on. */
924 inf
->vfork_parent
->pending_detach
= 0;
926 gdb::optional
<scoped_restore_exited_inferior
>
927 maybe_restore_inferior
;
928 gdb::optional
<scoped_restore_current_pspace_and_thread
>
929 maybe_restore_thread
;
931 /* If we're handling a child exit, then inferior_ptid points
932 at the inferior's pid, not to a thread. */
934 maybe_restore_inferior
.emplace ();
936 maybe_restore_thread
.emplace ();
938 /* We're letting loose of the parent. */
939 tp
= any_live_thread_of_process (inf
->vfork_parent
->pid
);
940 switch_to_thread (tp
->ptid
);
942 /* We're about to detach from the parent, which implicitly
943 removes breakpoints from its address space. There's a
944 catch here: we want to reuse the spaces for the child,
945 but, parent/child are still sharing the pspace at this
946 point, although the exec in reality makes the kernel give
947 the child a fresh set of new pages. The problem here is
948 that the breakpoints module being unaware of this, would
949 likely chose the child process to write to the parent
950 address space. Swapping the child temporarily away from
951 the spaces has the desired effect. Yes, this is "sort
954 pspace
= inf
->pspace
;
955 aspace
= inf
->aspace
;
959 if (debug_infrun
|| info_verbose
)
961 target_terminal::ours_for_output ();
965 fprintf_filtered (gdb_stdlog
,
966 _("Detaching vfork parent process "
967 "%d after child exec.\n"),
968 inf
->vfork_parent
->pid
);
972 fprintf_filtered (gdb_stdlog
,
973 _("Detaching vfork parent process "
974 "%d after child exit.\n"),
975 inf
->vfork_parent
->pid
);
979 target_detach (inf
->vfork_parent
, 0);
982 inf
->pspace
= pspace
;
983 inf
->aspace
= aspace
;
987 /* We're staying attached to the parent, so, really give the
988 child a new address space. */
989 inf
->pspace
= new program_space (maybe_new_address_space ());
990 inf
->aspace
= inf
->pspace
->aspace
;
992 set_current_program_space (inf
->pspace
);
994 resume_parent
= inf
->vfork_parent
->pid
;
996 /* Break the bonds. */
997 inf
->vfork_parent
->vfork_child
= NULL
;
1001 struct program_space
*pspace
;
1003 /* If this is a vfork child exiting, then the pspace and
1004 aspaces were shared with the parent. Since we're
1005 reporting the process exit, we'll be mourning all that is
1006 found in the address space, and switching to null_ptid,
1007 preparing to start a new inferior. But, since we don't
1008 want to clobber the parent's address/program spaces, we
1009 go ahead and create a new one for this exiting
1012 /* Switch to null_ptid while running clone_program_space, so
1013 that clone_program_space doesn't want to read the
1014 selected frame of a dead process. */
1015 scoped_restore restore_ptid
1016 = make_scoped_restore (&inferior_ptid
, null_ptid
);
1018 /* This inferior is dead, so avoid giving the breakpoints
1019 module the option to write through to it (cloning a
1020 program space resets breakpoints). */
1023 pspace
= new program_space (maybe_new_address_space ());
1024 set_current_program_space (pspace
);
1026 inf
->symfile_flags
= SYMFILE_NO_READ
;
1027 clone_program_space (pspace
, inf
->vfork_parent
->pspace
);
1028 inf
->pspace
= pspace
;
1029 inf
->aspace
= pspace
->aspace
;
1031 resume_parent
= inf
->vfork_parent
->pid
;
1032 /* Break the bonds. */
1033 inf
->vfork_parent
->vfork_child
= NULL
;
1036 inf
->vfork_parent
= NULL
;
1038 gdb_assert (current_program_space
== inf
->pspace
);
1040 if (non_stop
&& resume_parent
!= -1)
1042 /* If the user wanted the parent to be running, let it go
1044 scoped_restore_current_thread restore_thread
;
1047 fprintf_unfiltered (gdb_stdlog
,
1048 "infrun: resuming vfork parent process %d\n",
1051 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
1056 /* Enum strings for "set|show follow-exec-mode". */
1058 static const char follow_exec_mode_new
[] = "new";
1059 static const char follow_exec_mode_same
[] = "same";
1060 static const char *const follow_exec_mode_names
[] =
1062 follow_exec_mode_new
,
1063 follow_exec_mode_same
,
1067 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1069 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1070 struct cmd_list_element
*c
, const char *value
)
1072 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1075 /* EXEC_FILE_TARGET is assumed to be non-NULL. */
1078 follow_exec (ptid_t ptid
, char *exec_file_target
)
1080 struct thread_info
*th
, *tmp
;
1081 struct inferior
*inf
= current_inferior ();
1082 int pid
= ptid_get_pid (ptid
);
1083 ptid_t process_ptid
;
1085 /* This is an exec event that we actually wish to pay attention to.
1086 Refresh our symbol table to the newly exec'd program, remove any
1087 momentary bp's, etc.
1089 If there are breakpoints, they aren't really inserted now,
1090 since the exec() transformed our inferior into a fresh set
1093 We want to preserve symbolic breakpoints on the list, since
1094 we have hopes that they can be reset after the new a.out's
1095 symbol table is read.
1097 However, any "raw" breakpoints must be removed from the list
1098 (e.g., the solib bp's), since their address is probably invalid
1101 And, we DON'T want to call delete_breakpoints() here, since
1102 that may write the bp's "shadow contents" (the instruction
1103 value that was overwritten witha TRAP instruction). Since
1104 we now have a new a.out, those shadow contents aren't valid. */
1106 mark_breakpoints_out ();
1108 /* The target reports the exec event to the main thread, even if
1109 some other thread does the exec, and even if the main thread was
1110 stopped or already gone. We may still have non-leader threads of
1111 the process on our list. E.g., on targets that don't have thread
1112 exit events (like remote); or on native Linux in non-stop mode if
1113 there were only two threads in the inferior and the non-leader
1114 one is the one that execs (and nothing forces an update of the
1115 thread list up to here). When debugging remotely, it's best to
1116 avoid extra traffic, when possible, so avoid syncing the thread
1117 list with the target, and instead go ahead and delete all threads
1118 of the process but one that reported the event. Note this must
1119 be done before calling update_breakpoints_after_exec, as
1120 otherwise clearing the threads' resources would reference stale
1121 thread breakpoints -- it may have been one of these threads that
1122 stepped across the exec. We could just clear their stepping
1123 states, but as long as we're iterating, might as well delete
1124 them. Deleting them now rather than at the next user-visible
1125 stop provides a nicer sequence of events for user and MI
1127 ALL_THREADS_SAFE (th
, tmp
)
1128 if (ptid_get_pid (th
->ptid
) == pid
&& !ptid_equal (th
->ptid
, ptid
))
1129 delete_thread (th
->ptid
);
1131 /* We also need to clear any left over stale state for the
1132 leader/event thread. E.g., if there was any step-resume
1133 breakpoint or similar, it's gone now. We cannot truly
1134 step-to-next statement through an exec(). */
1135 th
= inferior_thread ();
1136 th
->control
.step_resume_breakpoint
= NULL
;
1137 th
->control
.exception_resume_breakpoint
= NULL
;
1138 th
->control
.single_step_breakpoints
= NULL
;
1139 th
->control
.step_range_start
= 0;
1140 th
->control
.step_range_end
= 0;
1142 /* The user may have had the main thread held stopped in the
1143 previous image (e.g., schedlock on, or non-stop). Release
1145 th
->stop_requested
= 0;
1147 update_breakpoints_after_exec ();
1149 /* What is this a.out's name? */
1150 process_ptid
= pid_to_ptid (pid
);
1151 printf_unfiltered (_("%s is executing new program: %s\n"),
1152 target_pid_to_str (process_ptid
),
1155 /* We've followed the inferior through an exec. Therefore, the
1156 inferior has essentially been killed & reborn. */
1158 gdb_flush (gdb_stdout
);
1160 breakpoint_init_inferior (inf_execd
);
1162 gdb::unique_xmalloc_ptr
<char> exec_file_host
1163 = exec_file_find (exec_file_target
, NULL
);
1165 /* If we were unable to map the executable target pathname onto a host
1166 pathname, tell the user that. Otherwise GDB's subsequent behavior
1167 is confusing. Maybe it would even be better to stop at this point
1168 so that the user can specify a file manually before continuing. */
1169 if (exec_file_host
== NULL
)
1170 warning (_("Could not load symbols for executable %s.\n"
1171 "Do you need \"set sysroot\"?"),
1174 /* Reset the shared library package. This ensures that we get a
1175 shlib event when the child reaches "_start", at which point the
1176 dld will have had a chance to initialize the child. */
1177 /* Also, loading a symbol file below may trigger symbol lookups, and
1178 we don't want those to be satisfied by the libraries of the
1179 previous incarnation of this process. */
1180 no_shared_libraries (NULL
, 0);
1182 if (follow_exec_mode_string
== follow_exec_mode_new
)
1184 /* The user wants to keep the old inferior and program spaces
1185 around. Create a new fresh one, and switch to it. */
1187 /* Do exit processing for the original inferior before adding
1188 the new inferior so we don't have two active inferiors with
1189 the same ptid, which can confuse find_inferior_ptid. */
1190 exit_inferior_num_silent (current_inferior ()->num
);
1192 inf
= add_inferior_with_spaces ();
1194 target_follow_exec (inf
, exec_file_target
);
1196 set_current_inferior (inf
);
1197 set_current_program_space (inf
->pspace
);
1201 /* The old description may no longer be fit for the new image.
1202 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1203 old description; we'll read a new one below. No need to do
1204 this on "follow-exec-mode new", as the old inferior stays
1205 around (its description is later cleared/refetched on
1207 target_clear_description ();
1210 gdb_assert (current_program_space
== inf
->pspace
);
1212 /* Attempt to open the exec file. SYMFILE_DEFER_BP_RESET is used
1213 because the proper displacement for a PIE (Position Independent
1214 Executable) main symbol file will only be computed by
1215 solib_create_inferior_hook below. breakpoint_re_set would fail
1216 to insert the breakpoints with the zero displacement. */
1217 try_open_exec_file (exec_file_host
.get (), inf
, SYMFILE_DEFER_BP_RESET
);
1219 /* If the target can specify a description, read it. Must do this
1220 after flipping to the new executable (because the target supplied
1221 description must be compatible with the executable's
1222 architecture, and the old executable may e.g., be 32-bit, while
1223 the new one 64-bit), and before anything involving memory or
1225 target_find_description ();
1227 /* The add_thread call ends up reading registers, so do it after updating the
1228 target description. */
1229 if (follow_exec_mode_string
== follow_exec_mode_new
)
1232 solib_create_inferior_hook (0);
1234 jit_inferior_created_hook ();
1236 breakpoint_re_set ();
1238 /* Reinsert all breakpoints. (Those which were symbolic have
1239 been reset to the proper address in the new a.out, thanks
1240 to symbol_file_command...). */
1241 insert_breakpoints ();
1243 /* The next resume of this inferior should bring it to the shlib
1244 startup breakpoints. (If the user had also set bp's on
1245 "main" from the old (parent) process, then they'll auto-
1246 matically get reset there in the new process.). */
1249 /* The queue of threads that need to do a step-over operation to get
1250 past e.g., a breakpoint. What technique is used to step over the
1251 breakpoint/watchpoint does not matter -- all threads end up in the
1252 same queue, to maintain rough temporal order of execution, in order
1253 to avoid starvation, otherwise, we could e.g., find ourselves
1254 constantly stepping the same couple threads past their breakpoints
1255 over and over, if the single-step finish fast enough. */
1256 struct thread_info
*step_over_queue_head
;
1258 /* Bit flags indicating what the thread needs to step over. */
1260 enum step_over_what_flag
1262 /* Step over a breakpoint. */
1263 STEP_OVER_BREAKPOINT
= 1,
1265 /* Step past a non-continuable watchpoint, in order to let the
1266 instruction execute so we can evaluate the watchpoint
1268 STEP_OVER_WATCHPOINT
= 2
1270 DEF_ENUM_FLAGS_TYPE (enum step_over_what_flag
, step_over_what
);
1272 /* Info about an instruction that is being stepped over. */
1274 struct step_over_info
1276 /* If we're stepping past a breakpoint, this is the address space
1277 and address of the instruction the breakpoint is set at. We'll
1278 skip inserting all breakpoints here. Valid iff ASPACE is
1280 const address_space
*aspace
;
1283 /* The instruction being stepped over triggers a nonsteppable
1284 watchpoint. If true, we'll skip inserting watchpoints. */
1285 int nonsteppable_watchpoint_p
;
1287 /* The thread's global number. */
1291 /* The step-over info of the location that is being stepped over.
1293 Note that with async/breakpoint always-inserted mode, a user might
1294 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1295 being stepped over. As setting a new breakpoint inserts all
1296 breakpoints, we need to make sure the breakpoint being stepped over
1297 isn't inserted then. We do that by only clearing the step-over
1298 info when the step-over is actually finished (or aborted).
1300 Presently GDB can only step over one breakpoint at any given time.
1301 Given threads that can't run code in the same address space as the
1302 breakpoint's can't really miss the breakpoint, GDB could be taught
1303 to step-over at most one breakpoint per address space (so this info
1304 could move to the address space object if/when GDB is extended).
1305 The set of breakpoints being stepped over will normally be much
1306 smaller than the set of all breakpoints, so a flag in the
1307 breakpoint location structure would be wasteful. A separate list
1308 also saves complexity and run-time, as otherwise we'd have to go
1309 through all breakpoint locations clearing their flag whenever we
1310 start a new sequence. Similar considerations weigh against storing
1311 this info in the thread object. Plus, not all step overs actually
1312 have breakpoint locations -- e.g., stepping past a single-step
1313 breakpoint, or stepping to complete a non-continuable
1315 static struct step_over_info step_over_info
;
1317 /* Record the address of the breakpoint/instruction we're currently
1319 N.B. We record the aspace and address now, instead of say just the thread,
1320 because when we need the info later the thread may be running. */
1323 set_step_over_info (const address_space
*aspace
, CORE_ADDR address
,
1324 int nonsteppable_watchpoint_p
,
1327 step_over_info
.aspace
= aspace
;
1328 step_over_info
.address
= address
;
1329 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1330 step_over_info
.thread
= thread
;
1333 /* Called when we're not longer stepping over a breakpoint / an
1334 instruction, so all breakpoints are free to be (re)inserted. */
1337 clear_step_over_info (void)
1340 fprintf_unfiltered (gdb_stdlog
,
1341 "infrun: clear_step_over_info\n");
1342 step_over_info
.aspace
= NULL
;
1343 step_over_info
.address
= 0;
1344 step_over_info
.nonsteppable_watchpoint_p
= 0;
1345 step_over_info
.thread
= -1;
1351 stepping_past_instruction_at (struct address_space
*aspace
,
1354 return (step_over_info
.aspace
!= NULL
1355 && breakpoint_address_match (aspace
, address
,
1356 step_over_info
.aspace
,
1357 step_over_info
.address
));
1363 thread_is_stepping_over_breakpoint (int thread
)
1365 return (step_over_info
.thread
!= -1
1366 && thread
== step_over_info
.thread
);
1372 stepping_past_nonsteppable_watchpoint (void)
1374 return step_over_info
.nonsteppable_watchpoint_p
;
1377 /* Returns true if step-over info is valid. */
1380 step_over_info_valid_p (void)
1382 return (step_over_info
.aspace
!= NULL
1383 || stepping_past_nonsteppable_watchpoint ());
1387 /* Displaced stepping. */
1389 /* In non-stop debugging mode, we must take special care to manage
1390 breakpoints properly; in particular, the traditional strategy for
1391 stepping a thread past a breakpoint it has hit is unsuitable.
1392 'Displaced stepping' is a tactic for stepping one thread past a
1393 breakpoint it has hit while ensuring that other threads running
1394 concurrently will hit the breakpoint as they should.
1396 The traditional way to step a thread T off a breakpoint in a
1397 multi-threaded program in all-stop mode is as follows:
1399 a0) Initially, all threads are stopped, and breakpoints are not
1401 a1) We single-step T, leaving breakpoints uninserted.
1402 a2) We insert breakpoints, and resume all threads.
1404 In non-stop debugging, however, this strategy is unsuitable: we
1405 don't want to have to stop all threads in the system in order to
1406 continue or step T past a breakpoint. Instead, we use displaced
1409 n0) Initially, T is stopped, other threads are running, and
1410 breakpoints are inserted.
1411 n1) We copy the instruction "under" the breakpoint to a separate
1412 location, outside the main code stream, making any adjustments
1413 to the instruction, register, and memory state as directed by
1415 n2) We single-step T over the instruction at its new location.
1416 n3) We adjust the resulting register and memory state as directed
1417 by T's architecture. This includes resetting T's PC to point
1418 back into the main instruction stream.
1421 This approach depends on the following gdbarch methods:
1423 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1424 indicate where to copy the instruction, and how much space must
1425 be reserved there. We use these in step n1.
1427 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1428 address, and makes any necessary adjustments to the instruction,
1429 register contents, and memory. We use this in step n1.
1431 - gdbarch_displaced_step_fixup adjusts registers and memory after
1432 we have successfuly single-stepped the instruction, to yield the
1433 same effect the instruction would have had if we had executed it
1434 at its original address. We use this in step n3.
1436 The gdbarch_displaced_step_copy_insn and
1437 gdbarch_displaced_step_fixup functions must be written so that
1438 copying an instruction with gdbarch_displaced_step_copy_insn,
1439 single-stepping across the copied instruction, and then applying
1440 gdbarch_displaced_insn_fixup should have the same effects on the
1441 thread's memory and registers as stepping the instruction in place
1442 would have. Exactly which responsibilities fall to the copy and
1443 which fall to the fixup is up to the author of those functions.
1445 See the comments in gdbarch.sh for details.
1447 Note that displaced stepping and software single-step cannot
1448 currently be used in combination, although with some care I think
1449 they could be made to. Software single-step works by placing
1450 breakpoints on all possible subsequent instructions; if the
1451 displaced instruction is a PC-relative jump, those breakpoints
1452 could fall in very strange places --- on pages that aren't
1453 executable, or at addresses that are not proper instruction
1454 boundaries. (We do generally let other threads run while we wait
1455 to hit the software single-step breakpoint, and they might
1456 encounter such a corrupted instruction.) One way to work around
1457 this would be to have gdbarch_displaced_step_copy_insn fully
1458 simulate the effect of PC-relative instructions (and return NULL)
1459 on architectures that use software single-stepping.
1461 In non-stop mode, we can have independent and simultaneous step
1462 requests, so more than one thread may need to simultaneously step
1463 over a breakpoint. The current implementation assumes there is
1464 only one scratch space per process. In this case, we have to
1465 serialize access to the scratch space. If thread A wants to step
1466 over a breakpoint, but we are currently waiting for some other
1467 thread to complete a displaced step, we leave thread A stopped and
1468 place it in the displaced_step_request_queue. Whenever a displaced
1469 step finishes, we pick the next thread in the queue and start a new
1470 displaced step operation on it. See displaced_step_prepare and
1471 displaced_step_fixup for details. */
1473 /* Default destructor for displaced_step_closure. */
1475 displaced_step_closure::~displaced_step_closure () = default;
1477 /* Per-inferior displaced stepping state. */
1478 struct displaced_step_inferior_state
1480 /* Pointer to next in linked list. */
1481 struct displaced_step_inferior_state
*next
;
1483 /* The process this displaced step state refers to. */
1486 /* True if preparing a displaced step ever failed. If so, we won't
1487 try displaced stepping for this inferior again. */
1490 /* If this is not null_ptid, this is the thread carrying out a
1491 displaced single-step in process PID. This thread's state will
1492 require fixing up once it has completed its step. */
1495 /* The architecture the thread had when we stepped it. */
1496 struct gdbarch
*step_gdbarch
;
1498 /* The closure provided gdbarch_displaced_step_copy_insn, to be used
1499 for post-step cleanup. */
1500 struct displaced_step_closure
*step_closure
;
1502 /* The address of the original instruction, and the copy we
1504 CORE_ADDR step_original
, step_copy
;
1506 /* Saved contents of copy area. */
1507 gdb_byte
*step_saved_copy
;
1510 /* The list of states of processes involved in displaced stepping
1512 static struct displaced_step_inferior_state
*displaced_step_inferior_states
;
1514 /* Get the displaced stepping state of process PID. */
1516 static struct displaced_step_inferior_state
*
1517 get_displaced_stepping_state (int pid
)
1519 struct displaced_step_inferior_state
*state
;
1521 for (state
= displaced_step_inferior_states
;
1523 state
= state
->next
)
1524 if (state
->pid
== pid
)
1530 /* Returns true if any inferior has a thread doing a displaced
1534 displaced_step_in_progress_any_inferior (void)
1536 struct displaced_step_inferior_state
*state
;
1538 for (state
= displaced_step_inferior_states
;
1540 state
= state
->next
)
1541 if (!ptid_equal (state
->step_ptid
, null_ptid
))
1547 /* Return true if thread represented by PTID is doing a displaced
1551 displaced_step_in_progress_thread (ptid_t ptid
)
1553 struct displaced_step_inferior_state
*displaced
;
1555 gdb_assert (!ptid_equal (ptid
, null_ptid
));
1557 displaced
= get_displaced_stepping_state (ptid_get_pid (ptid
));
1559 return (displaced
!= NULL
&& ptid_equal (displaced
->step_ptid
, ptid
));
1562 /* Return true if process PID has a thread doing a displaced step. */
1565 displaced_step_in_progress (int pid
)
1567 struct displaced_step_inferior_state
*displaced
;
1569 displaced
= get_displaced_stepping_state (pid
);
1570 if (displaced
!= NULL
&& !ptid_equal (displaced
->step_ptid
, null_ptid
))
1576 /* Add a new displaced stepping state for process PID to the displaced
1577 stepping state list, or return a pointer to an already existing
1578 entry, if it already exists. Never returns NULL. */
1580 static struct displaced_step_inferior_state
*
1581 add_displaced_stepping_state (int pid
)
1583 struct displaced_step_inferior_state
*state
;
1585 for (state
= displaced_step_inferior_states
;
1587 state
= state
->next
)
1588 if (state
->pid
== pid
)
1591 state
= XCNEW (struct displaced_step_inferior_state
);
1593 state
->next
= displaced_step_inferior_states
;
1594 displaced_step_inferior_states
= state
;
1599 /* If inferior is in displaced stepping, and ADDR equals to starting address
1600 of copy area, return corresponding displaced_step_closure. Otherwise,
1603 struct displaced_step_closure
*
1604 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1606 struct displaced_step_inferior_state
*displaced
1607 = get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
1609 /* If checking the mode of displaced instruction in copy area. */
1610 if (displaced
&& !ptid_equal (displaced
->step_ptid
, null_ptid
)
1611 && (displaced
->step_copy
== addr
))
1612 return displaced
->step_closure
;
1617 /* Remove the displaced stepping state of process PID. */
1620 remove_displaced_stepping_state (int pid
)
1622 struct displaced_step_inferior_state
*it
, **prev_next_p
;
1624 gdb_assert (pid
!= 0);
1626 it
= displaced_step_inferior_states
;
1627 prev_next_p
= &displaced_step_inferior_states
;
1632 *prev_next_p
= it
->next
;
1637 prev_next_p
= &it
->next
;
1643 infrun_inferior_exit (struct inferior
*inf
)
1645 remove_displaced_stepping_state (inf
->pid
);
1648 /* If ON, and the architecture supports it, GDB will use displaced
1649 stepping to step over breakpoints. If OFF, or if the architecture
1650 doesn't support it, GDB will instead use the traditional
1651 hold-and-step approach. If AUTO (which is the default), GDB will
1652 decide which technique to use to step over breakpoints depending on
1653 which of all-stop or non-stop mode is active --- displaced stepping
1654 in non-stop mode; hold-and-step in all-stop mode. */
1656 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1659 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1660 struct cmd_list_element
*c
,
1663 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1664 fprintf_filtered (file
,
1665 _("Debugger's willingness to use displaced stepping "
1666 "to step over breakpoints is %s (currently %s).\n"),
1667 value
, target_is_non_stop_p () ? "on" : "off");
1669 fprintf_filtered (file
,
1670 _("Debugger's willingness to use displaced stepping "
1671 "to step over breakpoints is %s.\n"), value
);
1674 /* Return non-zero if displaced stepping can/should be used to step
1675 over breakpoints of thread TP. */
1678 use_displaced_stepping (struct thread_info
*tp
)
1680 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
1681 struct gdbarch
*gdbarch
= regcache
->arch ();
1682 struct displaced_step_inferior_state
*displaced_state
;
1684 displaced_state
= get_displaced_stepping_state (ptid_get_pid (tp
->ptid
));
1686 return (((can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
1687 && target_is_non_stop_p ())
1688 || can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1689 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1690 && find_record_target () == NULL
1691 && (displaced_state
== NULL
1692 || !displaced_state
->failed_before
));
1695 /* Clean out any stray displaced stepping state. */
1697 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1699 /* Indicate that there is no cleanup pending. */
1700 displaced
->step_ptid
= null_ptid
;
1702 delete displaced
->step_closure
;
1703 displaced
->step_closure
= NULL
;
1707 displaced_step_clear_cleanup (void *arg
)
1709 struct displaced_step_inferior_state
*state
1710 = (struct displaced_step_inferior_state
*) arg
;
1712 displaced_step_clear (state
);
1715 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1717 displaced_step_dump_bytes (struct ui_file
*file
,
1718 const gdb_byte
*buf
,
1723 for (i
= 0; i
< len
; i
++)
1724 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1725 fputs_unfiltered ("\n", file
);
1728 /* Prepare to single-step, using displaced stepping.
1730 Note that we cannot use displaced stepping when we have a signal to
1731 deliver. If we have a signal to deliver and an instruction to step
1732 over, then after the step, there will be no indication from the
1733 target whether the thread entered a signal handler or ignored the
1734 signal and stepped over the instruction successfully --- both cases
1735 result in a simple SIGTRAP. In the first case we mustn't do a
1736 fixup, and in the second case we must --- but we can't tell which.
1737 Comments in the code for 'random signals' in handle_inferior_event
1738 explain how we handle this case instead.
1740 Returns 1 if preparing was successful -- this thread is going to be
1741 stepped now; 0 if displaced stepping this thread got queued; or -1
1742 if this instruction can't be displaced stepped. */
1745 displaced_step_prepare_throw (ptid_t ptid
)
1747 struct cleanup
*ignore_cleanups
;
1748 struct thread_info
*tp
= find_thread_ptid (ptid
);
1749 struct regcache
*regcache
= get_thread_regcache (ptid
);
1750 struct gdbarch
*gdbarch
= regcache
->arch ();
1751 const address_space
*aspace
= regcache
->aspace ();
1752 CORE_ADDR original
, copy
;
1754 struct displaced_step_closure
*closure
;
1755 struct displaced_step_inferior_state
*displaced
;
1758 /* We should never reach this function if the architecture does not
1759 support displaced stepping. */
1760 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1762 /* Nor if the thread isn't meant to step over a breakpoint. */
1763 gdb_assert (tp
->control
.trap_expected
);
1765 /* Disable range stepping while executing in the scratch pad. We
1766 want a single-step even if executing the displaced instruction in
1767 the scratch buffer lands within the stepping range (e.g., a
1769 tp
->control
.may_range_step
= 0;
1771 /* We have to displaced step one thread at a time, as we only have
1772 access to a single scratch space per inferior. */
1774 displaced
= add_displaced_stepping_state (ptid_get_pid (ptid
));
1776 if (!ptid_equal (displaced
->step_ptid
, null_ptid
))
1778 /* Already waiting for a displaced step to finish. Defer this
1779 request and place in queue. */
1781 if (debug_displaced
)
1782 fprintf_unfiltered (gdb_stdlog
,
1783 "displaced: deferring step of %s\n",
1784 target_pid_to_str (ptid
));
1786 thread_step_over_chain_enqueue (tp
);
1791 if (debug_displaced
)
1792 fprintf_unfiltered (gdb_stdlog
,
1793 "displaced: stepping %s now\n",
1794 target_pid_to_str (ptid
));
1797 displaced_step_clear (displaced
);
1799 scoped_restore save_inferior_ptid
= make_scoped_restore (&inferior_ptid
);
1800 inferior_ptid
= ptid
;
1802 original
= regcache_read_pc (regcache
);
1804 copy
= gdbarch_displaced_step_location (gdbarch
);
1805 len
= gdbarch_max_insn_length (gdbarch
);
1807 if (breakpoint_in_range_p (aspace
, copy
, len
))
1809 /* There's a breakpoint set in the scratch pad location range
1810 (which is usually around the entry point). We'd either
1811 install it before resuming, which would overwrite/corrupt the
1812 scratch pad, or if it was already inserted, this displaced
1813 step would overwrite it. The latter is OK in the sense that
1814 we already assume that no thread is going to execute the code
1815 in the scratch pad range (after initial startup) anyway, but
1816 the former is unacceptable. Simply punt and fallback to
1817 stepping over this breakpoint in-line. */
1818 if (debug_displaced
)
1820 fprintf_unfiltered (gdb_stdlog
,
1821 "displaced: breakpoint set in scratch pad. "
1822 "Stepping over breakpoint in-line instead.\n");
1828 /* Save the original contents of the copy area. */
1829 displaced
->step_saved_copy
= (gdb_byte
*) xmalloc (len
);
1830 ignore_cleanups
= make_cleanup (free_current_contents
,
1831 &displaced
->step_saved_copy
);
1832 status
= target_read_memory (copy
, displaced
->step_saved_copy
, len
);
1834 throw_error (MEMORY_ERROR
,
1835 _("Error accessing memory address %s (%s) for "
1836 "displaced-stepping scratch space."),
1837 paddress (gdbarch
, copy
), safe_strerror (status
));
1838 if (debug_displaced
)
1840 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1841 paddress (gdbarch
, copy
));
1842 displaced_step_dump_bytes (gdb_stdlog
,
1843 displaced
->step_saved_copy
,
1847 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1848 original
, copy
, regcache
);
1849 if (closure
== NULL
)
1851 /* The architecture doesn't know how or want to displaced step
1852 this instruction or instruction sequence. Fallback to
1853 stepping over the breakpoint in-line. */
1854 do_cleanups (ignore_cleanups
);
1858 /* Save the information we need to fix things up if the step
1860 displaced
->step_ptid
= ptid
;
1861 displaced
->step_gdbarch
= gdbarch
;
1862 displaced
->step_closure
= closure
;
1863 displaced
->step_original
= original
;
1864 displaced
->step_copy
= copy
;
1866 make_cleanup (displaced_step_clear_cleanup
, displaced
);
1868 /* Resume execution at the copy. */
1869 regcache_write_pc (regcache
, copy
);
1871 discard_cleanups (ignore_cleanups
);
1873 if (debug_displaced
)
1874 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1875 paddress (gdbarch
, copy
));
1880 /* Wrapper for displaced_step_prepare_throw that disabled further
1881 attempts at displaced stepping if we get a memory error. */
1884 displaced_step_prepare (ptid_t ptid
)
1890 prepared
= displaced_step_prepare_throw (ptid
);
1892 CATCH (ex
, RETURN_MASK_ERROR
)
1894 struct displaced_step_inferior_state
*displaced_state
;
1896 if (ex
.error
!= MEMORY_ERROR
1897 && ex
.error
!= NOT_SUPPORTED_ERROR
)
1898 throw_exception (ex
);
1902 fprintf_unfiltered (gdb_stdlog
,
1903 "infrun: disabling displaced stepping: %s\n",
1907 /* Be verbose if "set displaced-stepping" is "on", silent if
1909 if (can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1911 warning (_("disabling displaced stepping: %s"),
1915 /* Disable further displaced stepping attempts. */
1917 = get_displaced_stepping_state (ptid_get_pid (ptid
));
1918 displaced_state
->failed_before
= 1;
1926 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1927 const gdb_byte
*myaddr
, int len
)
1929 scoped_restore save_inferior_ptid
= make_scoped_restore (&inferior_ptid
);
1931 inferior_ptid
= ptid
;
1932 write_memory (memaddr
, myaddr
, len
);
1935 /* Restore the contents of the copy area for thread PTID. */
1938 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1941 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1943 write_memory_ptid (ptid
, displaced
->step_copy
,
1944 displaced
->step_saved_copy
, len
);
1945 if (debug_displaced
)
1946 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1947 target_pid_to_str (ptid
),
1948 paddress (displaced
->step_gdbarch
,
1949 displaced
->step_copy
));
1952 /* If we displaced stepped an instruction successfully, adjust
1953 registers and memory to yield the same effect the instruction would
1954 have had if we had executed it at its original address, and return
1955 1. If the instruction didn't complete, relocate the PC and return
1956 -1. If the thread wasn't displaced stepping, return 0. */
1959 displaced_step_fixup (ptid_t event_ptid
, enum gdb_signal signal
)
1961 struct cleanup
*old_cleanups
;
1962 struct displaced_step_inferior_state
*displaced
1963 = get_displaced_stepping_state (ptid_get_pid (event_ptid
));
1966 /* Was any thread of this process doing a displaced step? */
1967 if (displaced
== NULL
)
1970 /* Was this event for the pid we displaced? */
1971 if (ptid_equal (displaced
->step_ptid
, null_ptid
)
1972 || ! ptid_equal (displaced
->step_ptid
, event_ptid
))
1975 old_cleanups
= make_cleanup (displaced_step_clear_cleanup
, displaced
);
1977 displaced_step_restore (displaced
, displaced
->step_ptid
);
1979 /* Fixup may need to read memory/registers. Switch to the thread
1980 that we're fixing up. Also, target_stopped_by_watchpoint checks
1981 the current thread. */
1982 switch_to_thread (event_ptid
);
1984 /* Did the instruction complete successfully? */
1985 if (signal
== GDB_SIGNAL_TRAP
1986 && !(target_stopped_by_watchpoint ()
1987 && (gdbarch_have_nonsteppable_watchpoint (displaced
->step_gdbarch
)
1988 || target_have_steppable_watchpoint
)))
1990 /* Fix up the resulting state. */
1991 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
1992 displaced
->step_closure
,
1993 displaced
->step_original
,
1994 displaced
->step_copy
,
1995 get_thread_regcache (displaced
->step_ptid
));
2000 /* Since the instruction didn't complete, all we can do is
2002 struct regcache
*regcache
= get_thread_regcache (event_ptid
);
2003 CORE_ADDR pc
= regcache_read_pc (regcache
);
2005 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
2006 regcache_write_pc (regcache
, pc
);
2010 do_cleanups (old_cleanups
);
2012 displaced
->step_ptid
= null_ptid
;
2017 /* Data to be passed around while handling an event. This data is
2018 discarded between events. */
2019 struct execution_control_state
2022 /* The thread that got the event, if this was a thread event; NULL
2024 struct thread_info
*event_thread
;
2026 struct target_waitstatus ws
;
2027 int stop_func_filled_in
;
2028 CORE_ADDR stop_func_start
;
2029 CORE_ADDR stop_func_end
;
2030 const char *stop_func_name
;
2033 /* True if the event thread hit the single-step breakpoint of
2034 another thread. Thus the event doesn't cause a stop, the thread
2035 needs to be single-stepped past the single-step breakpoint before
2036 we can switch back to the original stepping thread. */
2037 int hit_singlestep_breakpoint
;
2040 /* Clear ECS and set it to point at TP. */
2043 reset_ecs (struct execution_control_state
*ecs
, struct thread_info
*tp
)
2045 memset (ecs
, 0, sizeof (*ecs
));
2046 ecs
->event_thread
= tp
;
2047 ecs
->ptid
= tp
->ptid
;
2050 static void keep_going_pass_signal (struct execution_control_state
*ecs
);
2051 static void prepare_to_wait (struct execution_control_state
*ecs
);
2052 static int keep_going_stepped_thread (struct thread_info
*tp
);
2053 static step_over_what
thread_still_needs_step_over (struct thread_info
*tp
);
2055 /* Are there any pending step-over requests? If so, run all we can
2056 now and return true. Otherwise, return false. */
2059 start_step_over (void)
2061 struct thread_info
*tp
, *next
;
2063 /* Don't start a new step-over if we already have an in-line
2064 step-over operation ongoing. */
2065 if (step_over_info_valid_p ())
2068 for (tp
= step_over_queue_head
; tp
!= NULL
; tp
= next
)
2070 struct execution_control_state ecss
;
2071 struct execution_control_state
*ecs
= &ecss
;
2072 step_over_what step_what
;
2073 int must_be_in_line
;
2075 gdb_assert (!tp
->stop_requested
);
2077 next
= thread_step_over_chain_next (tp
);
2079 /* If this inferior already has a displaced step in process,
2080 don't start a new one. */
2081 if (displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2084 step_what
= thread_still_needs_step_over (tp
);
2085 must_be_in_line
= ((step_what
& STEP_OVER_WATCHPOINT
)
2086 || ((step_what
& STEP_OVER_BREAKPOINT
)
2087 && !use_displaced_stepping (tp
)));
2089 /* We currently stop all threads of all processes to step-over
2090 in-line. If we need to start a new in-line step-over, let
2091 any pending displaced steps finish first. */
2092 if (must_be_in_line
&& displaced_step_in_progress_any_inferior ())
2095 thread_step_over_chain_remove (tp
);
2097 if (step_over_queue_head
== NULL
)
2100 fprintf_unfiltered (gdb_stdlog
,
2101 "infrun: step-over queue now empty\n");
2104 if (tp
->control
.trap_expected
2108 internal_error (__FILE__
, __LINE__
,
2109 "[%s] has inconsistent state: "
2110 "trap_expected=%d, resumed=%d, executing=%d\n",
2111 target_pid_to_str (tp
->ptid
),
2112 tp
->control
.trap_expected
,
2118 fprintf_unfiltered (gdb_stdlog
,
2119 "infrun: resuming [%s] for step-over\n",
2120 target_pid_to_str (tp
->ptid
));
2122 /* keep_going_pass_signal skips the step-over if the breakpoint
2123 is no longer inserted. In all-stop, we want to keep looking
2124 for a thread that needs a step-over instead of resuming TP,
2125 because we wouldn't be able to resume anything else until the
2126 target stops again. In non-stop, the resume always resumes
2127 only TP, so it's OK to let the thread resume freely. */
2128 if (!target_is_non_stop_p () && !step_what
)
2131 switch_to_thread (tp
->ptid
);
2132 reset_ecs (ecs
, tp
);
2133 keep_going_pass_signal (ecs
);
2135 if (!ecs
->wait_some_more
)
2136 error (_("Command aborted."));
2138 gdb_assert (tp
->resumed
);
2140 /* If we started a new in-line step-over, we're done. */
2141 if (step_over_info_valid_p ())
2143 gdb_assert (tp
->control
.trap_expected
);
2147 if (!target_is_non_stop_p ())
2149 /* On all-stop, shouldn't have resumed unless we needed a
2151 gdb_assert (tp
->control
.trap_expected
2152 || tp
->step_after_step_resume_breakpoint
);
2154 /* With remote targets (at least), in all-stop, we can't
2155 issue any further remote commands until the program stops
2160 /* Either the thread no longer needed a step-over, or a new
2161 displaced stepping sequence started. Even in the latter
2162 case, continue looking. Maybe we can also start another
2163 displaced step on a thread of other process. */
2169 /* Update global variables holding ptids to hold NEW_PTID if they were
2170 holding OLD_PTID. */
2172 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
2174 struct displaced_step_inferior_state
*displaced
;
2176 if (ptid_equal (inferior_ptid
, old_ptid
))
2177 inferior_ptid
= new_ptid
;
2179 for (displaced
= displaced_step_inferior_states
;
2181 displaced
= displaced
->next
)
2183 if (ptid_equal (displaced
->step_ptid
, old_ptid
))
2184 displaced
->step_ptid
= new_ptid
;
2190 static const char schedlock_off
[] = "off";
2191 static const char schedlock_on
[] = "on";
2192 static const char schedlock_step
[] = "step";
2193 static const char schedlock_replay
[] = "replay";
2194 static const char *const scheduler_enums
[] = {
2201 static const char *scheduler_mode
= schedlock_replay
;
2203 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
2204 struct cmd_list_element
*c
, const char *value
)
2206 fprintf_filtered (file
,
2207 _("Mode for locking scheduler "
2208 "during execution is \"%s\".\n"),
2213 set_schedlock_func (const char *args
, int from_tty
, struct cmd_list_element
*c
)
2215 if (!target_can_lock_scheduler
)
2217 scheduler_mode
= schedlock_off
;
2218 error (_("Target '%s' cannot support this command."), target_shortname
);
2222 /* True if execution commands resume all threads of all processes by
2223 default; otherwise, resume only threads of the current inferior
2225 int sched_multi
= 0;
2227 /* Try to setup for software single stepping over the specified location.
2228 Return 1 if target_resume() should use hardware single step.
2230 GDBARCH the current gdbarch.
2231 PC the location to step over. */
2234 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
2238 if (execution_direction
== EXEC_FORWARD
2239 && gdbarch_software_single_step_p (gdbarch
))
2240 hw_step
= !insert_single_step_breakpoints (gdbarch
);
2248 user_visible_resume_ptid (int step
)
2254 /* With non-stop mode on, threads are always handled
2256 resume_ptid
= inferior_ptid
;
2258 else if ((scheduler_mode
== schedlock_on
)
2259 || (scheduler_mode
== schedlock_step
&& step
))
2261 /* User-settable 'scheduler' mode requires solo thread
2263 resume_ptid
= inferior_ptid
;
2265 else if ((scheduler_mode
== schedlock_replay
)
2266 && target_record_will_replay (minus_one_ptid
, execution_direction
))
2268 /* User-settable 'scheduler' mode requires solo thread resume in replay
2270 resume_ptid
= inferior_ptid
;
2272 else if (!sched_multi
&& target_supports_multi_process ())
2274 /* Resume all threads of the current process (and none of other
2276 resume_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
2280 /* Resume all threads of all processes. */
2281 resume_ptid
= RESUME_ALL
;
2287 /* Return a ptid representing the set of threads that we will resume,
2288 in the perspective of the target, assuming run control handling
2289 does not require leaving some threads stopped (e.g., stepping past
2290 breakpoint). USER_STEP indicates whether we're about to start the
2291 target for a stepping command. */
2294 internal_resume_ptid (int user_step
)
2296 /* In non-stop, we always control threads individually. Note that
2297 the target may always work in non-stop mode even with "set
2298 non-stop off", in which case user_visible_resume_ptid could
2299 return a wildcard ptid. */
2300 if (target_is_non_stop_p ())
2301 return inferior_ptid
;
2303 return user_visible_resume_ptid (user_step
);
2306 /* Wrapper for target_resume, that handles infrun-specific
2310 do_target_resume (ptid_t resume_ptid
, int step
, enum gdb_signal sig
)
2312 struct thread_info
*tp
= inferior_thread ();
2314 gdb_assert (!tp
->stop_requested
);
2316 /* Install inferior's terminal modes. */
2317 target_terminal::inferior ();
2319 /* Avoid confusing the next resume, if the next stop/resume
2320 happens to apply to another thread. */
2321 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2323 /* Advise target which signals may be handled silently.
2325 If we have removed breakpoints because we are stepping over one
2326 in-line (in any thread), we need to receive all signals to avoid
2327 accidentally skipping a breakpoint during execution of a signal
2330 Likewise if we're displaced stepping, otherwise a trap for a
2331 breakpoint in a signal handler might be confused with the
2332 displaced step finishing. We don't make the displaced_step_fixup
2333 step distinguish the cases instead, because:
2335 - a backtrace while stopped in the signal handler would show the
2336 scratch pad as frame older than the signal handler, instead of
2337 the real mainline code.
2339 - when the thread is later resumed, the signal handler would
2340 return to the scratch pad area, which would no longer be
2342 if (step_over_info_valid_p ()
2343 || displaced_step_in_progress (ptid_get_pid (tp
->ptid
)))
2344 target_pass_signals (0, NULL
);
2346 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
2348 target_resume (resume_ptid
, step
, sig
);
2350 target_commit_resume ();
2353 /* Resume the inferior. SIG is the signal to give the inferior
2354 (GDB_SIGNAL_0 for none). Note: don't call this directly; instead
2355 call 'resume', which handles exceptions. */
2358 resume_1 (enum gdb_signal sig
)
2360 struct regcache
*regcache
= get_current_regcache ();
2361 struct gdbarch
*gdbarch
= regcache
->arch ();
2362 struct thread_info
*tp
= inferior_thread ();
2363 CORE_ADDR pc
= regcache_read_pc (regcache
);
2364 const address_space
*aspace
= regcache
->aspace ();
2366 /* This represents the user's step vs continue request. When
2367 deciding whether "set scheduler-locking step" applies, it's the
2368 user's intention that counts. */
2369 const int user_step
= tp
->control
.stepping_command
;
2370 /* This represents what we'll actually request the target to do.
2371 This can decay from a step to a continue, if e.g., we need to
2372 implement single-stepping with breakpoints (software
2376 gdb_assert (!tp
->stop_requested
);
2377 gdb_assert (!thread_is_in_step_over_chain (tp
));
2379 if (tp
->suspend
.waitstatus_pending_p
)
2384 = target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2386 fprintf_unfiltered (gdb_stdlog
,
2387 "infrun: resume: thread %s has pending wait "
2388 "status %s (currently_stepping=%d).\n",
2389 target_pid_to_str (tp
->ptid
), statstr
.c_str (),
2390 currently_stepping (tp
));
2395 /* FIXME: What should we do if we are supposed to resume this
2396 thread with a signal? Maybe we should maintain a queue of
2397 pending signals to deliver. */
2398 if (sig
!= GDB_SIGNAL_0
)
2400 warning (_("Couldn't deliver signal %s to %s."),
2401 gdb_signal_to_name (sig
), target_pid_to_str (tp
->ptid
));
2404 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2406 if (target_can_async_p ())
2411 tp
->stepped_breakpoint
= 0;
2413 /* Depends on stepped_breakpoint. */
2414 step
= currently_stepping (tp
);
2416 if (current_inferior ()->waiting_for_vfork_done
)
2418 /* Don't try to single-step a vfork parent that is waiting for
2419 the child to get out of the shared memory region (by exec'ing
2420 or exiting). This is particularly important on software
2421 single-step archs, as the child process would trip on the
2422 software single step breakpoint inserted for the parent
2423 process. Since the parent will not actually execute any
2424 instruction until the child is out of the shared region (such
2425 are vfork's semantics), it is safe to simply continue it.
2426 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2427 the parent, and tell it to `keep_going', which automatically
2428 re-sets it stepping. */
2430 fprintf_unfiltered (gdb_stdlog
,
2431 "infrun: resume : clear step\n");
2436 fprintf_unfiltered (gdb_stdlog
,
2437 "infrun: resume (step=%d, signal=%s), "
2438 "trap_expected=%d, current thread [%s] at %s\n",
2439 step
, gdb_signal_to_symbol_string (sig
),
2440 tp
->control
.trap_expected
,
2441 target_pid_to_str (inferior_ptid
),
2442 paddress (gdbarch
, pc
));
2444 /* Normally, by the time we reach `resume', the breakpoints are either
2445 removed or inserted, as appropriate. The exception is if we're sitting
2446 at a permanent breakpoint; we need to step over it, but permanent
2447 breakpoints can't be removed. So we have to test for it here. */
2448 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2450 if (sig
!= GDB_SIGNAL_0
)
2452 /* We have a signal to pass to the inferior. The resume
2453 may, or may not take us to the signal handler. If this
2454 is a step, we'll need to stop in the signal handler, if
2455 there's one, (if the target supports stepping into
2456 handlers), or in the next mainline instruction, if
2457 there's no handler. If this is a continue, we need to be
2458 sure to run the handler with all breakpoints inserted.
2459 In all cases, set a breakpoint at the current address
2460 (where the handler returns to), and once that breakpoint
2461 is hit, resume skipping the permanent breakpoint. If
2462 that breakpoint isn't hit, then we've stepped into the
2463 signal handler (or hit some other event). We'll delete
2464 the step-resume breakpoint then. */
2467 fprintf_unfiltered (gdb_stdlog
,
2468 "infrun: resume: skipping permanent breakpoint, "
2469 "deliver signal first\n");
2471 clear_step_over_info ();
2472 tp
->control
.trap_expected
= 0;
2474 if (tp
->control
.step_resume_breakpoint
== NULL
)
2476 /* Set a "high-priority" step-resume, as we don't want
2477 user breakpoints at PC to trigger (again) when this
2479 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2480 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2482 tp
->step_after_step_resume_breakpoint
= step
;
2485 insert_breakpoints ();
2489 /* There's no signal to pass, we can go ahead and skip the
2490 permanent breakpoint manually. */
2492 fprintf_unfiltered (gdb_stdlog
,
2493 "infrun: resume: skipping permanent breakpoint\n");
2494 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2495 /* Update pc to reflect the new address from which we will
2496 execute instructions. */
2497 pc
= regcache_read_pc (regcache
);
2501 /* We've already advanced the PC, so the stepping part
2502 is done. Now we need to arrange for a trap to be
2503 reported to handle_inferior_event. Set a breakpoint
2504 at the current PC, and run to it. Don't update
2505 prev_pc, because if we end in
2506 switch_back_to_stepped_thread, we want the "expected
2507 thread advanced also" branch to be taken. IOW, we
2508 don't want this thread to step further from PC
2510 gdb_assert (!step_over_info_valid_p ());
2511 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2512 insert_breakpoints ();
2514 resume_ptid
= internal_resume_ptid (user_step
);
2515 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
2522 /* If we have a breakpoint to step over, make sure to do a single
2523 step only. Same if we have software watchpoints. */
2524 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2525 tp
->control
.may_range_step
= 0;
2527 /* If enabled, step over breakpoints by executing a copy of the
2528 instruction at a different address.
2530 We can't use displaced stepping when we have a signal to deliver;
2531 the comments for displaced_step_prepare explain why. The
2532 comments in the handle_inferior event for dealing with 'random
2533 signals' explain what we do instead.
2535 We can't use displaced stepping when we are waiting for vfork_done
2536 event, displaced stepping breaks the vfork child similarly as single
2537 step software breakpoint. */
2538 if (tp
->control
.trap_expected
2539 && use_displaced_stepping (tp
)
2540 && !step_over_info_valid_p ()
2541 && sig
== GDB_SIGNAL_0
2542 && !current_inferior ()->waiting_for_vfork_done
)
2544 int prepared
= displaced_step_prepare (inferior_ptid
);
2549 fprintf_unfiltered (gdb_stdlog
,
2550 "Got placed in step-over queue\n");
2552 tp
->control
.trap_expected
= 0;
2555 else if (prepared
< 0)
2557 /* Fallback to stepping over the breakpoint in-line. */
2559 if (target_is_non_stop_p ())
2560 stop_all_threads ();
2562 set_step_over_info (regcache
->aspace (),
2563 regcache_read_pc (regcache
), 0, tp
->global_num
);
2565 step
= maybe_software_singlestep (gdbarch
, pc
);
2567 insert_breakpoints ();
2569 else if (prepared
> 0)
2571 struct displaced_step_inferior_state
*displaced
;
2573 /* Update pc to reflect the new address from which we will
2574 execute instructions due to displaced stepping. */
2575 pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
2577 displaced
= get_displaced_stepping_state (ptid_get_pid (inferior_ptid
));
2578 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
2579 displaced
->step_closure
);
2583 /* Do we need to do it the hard way, w/temp breakpoints? */
2585 step
= maybe_software_singlestep (gdbarch
, pc
);
2587 /* Currently, our software single-step implementation leads to different
2588 results than hardware single-stepping in one situation: when stepping
2589 into delivering a signal which has an associated signal handler,
2590 hardware single-step will stop at the first instruction of the handler,
2591 while software single-step will simply skip execution of the handler.
2593 For now, this difference in behavior is accepted since there is no
2594 easy way to actually implement single-stepping into a signal handler
2595 without kernel support.
2597 However, there is one scenario where this difference leads to follow-on
2598 problems: if we're stepping off a breakpoint by removing all breakpoints
2599 and then single-stepping. In this case, the software single-step
2600 behavior means that even if there is a *breakpoint* in the signal
2601 handler, GDB still would not stop.
2603 Fortunately, we can at least fix this particular issue. We detect
2604 here the case where we are about to deliver a signal while software
2605 single-stepping with breakpoints removed. In this situation, we
2606 revert the decisions to remove all breakpoints and insert single-
2607 step breakpoints, and instead we install a step-resume breakpoint
2608 at the current address, deliver the signal without stepping, and
2609 once we arrive back at the step-resume breakpoint, actually step
2610 over the breakpoint we originally wanted to step over. */
2611 if (thread_has_single_step_breakpoints_set (tp
)
2612 && sig
!= GDB_SIGNAL_0
2613 && step_over_info_valid_p ())
2615 /* If we have nested signals or a pending signal is delivered
2616 immediately after a handler returns, might might already have
2617 a step-resume breakpoint set on the earlier handler. We cannot
2618 set another step-resume breakpoint; just continue on until the
2619 original breakpoint is hit. */
2620 if (tp
->control
.step_resume_breakpoint
== NULL
)
2622 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2623 tp
->step_after_step_resume_breakpoint
= 1;
2626 delete_single_step_breakpoints (tp
);
2628 clear_step_over_info ();
2629 tp
->control
.trap_expected
= 0;
2631 insert_breakpoints ();
2634 /* If STEP is set, it's a request to use hardware stepping
2635 facilities. But in that case, we should never
2636 use singlestep breakpoint. */
2637 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2639 /* Decide the set of threads to ask the target to resume. */
2640 if (tp
->control
.trap_expected
)
2642 /* We're allowing a thread to run past a breakpoint it has
2643 hit, either by single-stepping the thread with the breakpoint
2644 removed, or by displaced stepping, with the breakpoint inserted.
2645 In the former case, we need to single-step only this thread,
2646 and keep others stopped, as they can miss this breakpoint if
2647 allowed to run. That's not really a problem for displaced
2648 stepping, but, we still keep other threads stopped, in case
2649 another thread is also stopped for a breakpoint waiting for
2650 its turn in the displaced stepping queue. */
2651 resume_ptid
= inferior_ptid
;
2654 resume_ptid
= internal_resume_ptid (user_step
);
2656 if (execution_direction
!= EXEC_REVERSE
2657 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2659 /* There are two cases where we currently need to step a
2660 breakpoint instruction when we have a signal to deliver:
2662 - See handle_signal_stop where we handle random signals that
2663 could take out us out of the stepping range. Normally, in
2664 that case we end up continuing (instead of stepping) over the
2665 signal handler with a breakpoint at PC, but there are cases
2666 where we should _always_ single-step, even if we have a
2667 step-resume breakpoint, like when a software watchpoint is
2668 set. Assuming single-stepping and delivering a signal at the
2669 same time would takes us to the signal handler, then we could
2670 have removed the breakpoint at PC to step over it. However,
2671 some hardware step targets (like e.g., Mac OS) can't step
2672 into signal handlers, and for those, we need to leave the
2673 breakpoint at PC inserted, as otherwise if the handler
2674 recurses and executes PC again, it'll miss the breakpoint.
2675 So we leave the breakpoint inserted anyway, but we need to
2676 record that we tried to step a breakpoint instruction, so
2677 that adjust_pc_after_break doesn't end up confused.
2679 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2680 in one thread after another thread that was stepping had been
2681 momentarily paused for a step-over. When we re-resume the
2682 stepping thread, it may be resumed from that address with a
2683 breakpoint that hasn't trapped yet. Seen with
2684 gdb.threads/non-stop-fair-events.exp, on targets that don't
2685 do displaced stepping. */
2688 fprintf_unfiltered (gdb_stdlog
,
2689 "infrun: resume: [%s] stepped breakpoint\n",
2690 target_pid_to_str (tp
->ptid
));
2692 tp
->stepped_breakpoint
= 1;
2694 /* Most targets can step a breakpoint instruction, thus
2695 executing it normally. But if this one cannot, just
2696 continue and we will hit it anyway. */
2697 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2702 && tp
->control
.trap_expected
2703 && use_displaced_stepping (tp
)
2704 && !step_over_info_valid_p ())
2706 struct regcache
*resume_regcache
= get_thread_regcache (tp
->ptid
);
2707 struct gdbarch
*resume_gdbarch
= resume_regcache
->arch ();
2708 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2711 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
2712 paddress (resume_gdbarch
, actual_pc
));
2713 read_memory (actual_pc
, buf
, sizeof (buf
));
2714 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
2717 if (tp
->control
.may_range_step
)
2719 /* If we're resuming a thread with the PC out of the step
2720 range, then we're doing some nested/finer run control
2721 operation, like stepping the thread out of the dynamic
2722 linker or the displaced stepping scratch pad. We
2723 shouldn't have allowed a range step then. */
2724 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2727 do_target_resume (resume_ptid
, step
, sig
);
2731 /* Resume the inferior. SIG is the signal to give the inferior
2732 (GDB_SIGNAL_0 for none). This is a wrapper around 'resume_1' that
2733 rolls back state on error. */
2736 resume (gdb_signal sig
)
2742 CATCH (ex
, RETURN_MASK_ALL
)
2744 /* If resuming is being aborted for any reason, delete any
2745 single-step breakpoint resume_1 may have created, to avoid
2746 confusing the following resumption, and to avoid leaving
2747 single-step breakpoints perturbing other threads, in case
2748 we're running in non-stop mode. */
2749 if (inferior_ptid
!= null_ptid
)
2750 delete_single_step_breakpoints (inferior_thread ());
2751 throw_exception (ex
);
2761 /* Counter that tracks number of user visible stops. This can be used
2762 to tell whether a command has proceeded the inferior past the
2763 current location. This allows e.g., inferior function calls in
2764 breakpoint commands to not interrupt the command list. When the
2765 call finishes successfully, the inferior is standing at the same
2766 breakpoint as if nothing happened (and so we don't call
2768 static ULONGEST current_stop_id
;
2775 return current_stop_id
;
2778 /* Called when we report a user visible stop. */
2786 /* Clear out all variables saying what to do when inferior is continued.
2787 First do this, then set the ones you want, then call `proceed'. */
2790 clear_proceed_status_thread (struct thread_info
*tp
)
2793 fprintf_unfiltered (gdb_stdlog
,
2794 "infrun: clear_proceed_status_thread (%s)\n",
2795 target_pid_to_str (tp
->ptid
));
2797 /* If we're starting a new sequence, then the previous finished
2798 single-step is no longer relevant. */
2799 if (tp
->suspend
.waitstatus_pending_p
)
2801 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
2804 fprintf_unfiltered (gdb_stdlog
,
2805 "infrun: clear_proceed_status: pending "
2806 "event of %s was a finished step. "
2808 target_pid_to_str (tp
->ptid
));
2810 tp
->suspend
.waitstatus_pending_p
= 0;
2811 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2813 else if (debug_infrun
)
2816 = target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2818 fprintf_unfiltered (gdb_stdlog
,
2819 "infrun: clear_proceed_status_thread: thread %s "
2820 "has pending wait status %s "
2821 "(currently_stepping=%d).\n",
2822 target_pid_to_str (tp
->ptid
), statstr
.c_str (),
2823 currently_stepping (tp
));
2827 /* If this signal should not be seen by program, give it zero.
2828 Used for debugging signals. */
2829 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2830 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2832 thread_fsm_delete (tp
->thread_fsm
);
2833 tp
->thread_fsm
= NULL
;
2835 tp
->control
.trap_expected
= 0;
2836 tp
->control
.step_range_start
= 0;
2837 tp
->control
.step_range_end
= 0;
2838 tp
->control
.may_range_step
= 0;
2839 tp
->control
.step_frame_id
= null_frame_id
;
2840 tp
->control
.step_stack_frame_id
= null_frame_id
;
2841 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2842 tp
->control
.step_start_function
= NULL
;
2843 tp
->stop_requested
= 0;
2845 tp
->control
.stop_step
= 0;
2847 tp
->control
.proceed_to_finish
= 0;
2849 tp
->control
.stepping_command
= 0;
2851 /* Discard any remaining commands or status from previous stop. */
2852 bpstat_clear (&tp
->control
.stop_bpstat
);
2856 clear_proceed_status (int step
)
2858 /* With scheduler-locking replay, stop replaying other threads if we're
2859 not replaying the user-visible resume ptid.
2861 This is a convenience feature to not require the user to explicitly
2862 stop replaying the other threads. We're assuming that the user's
2863 intent is to resume tracing the recorded process. */
2864 if (!non_stop
&& scheduler_mode
== schedlock_replay
2865 && target_record_is_replaying (minus_one_ptid
)
2866 && !target_record_will_replay (user_visible_resume_ptid (step
),
2867 execution_direction
))
2868 target_record_stop_replaying ();
2872 struct thread_info
*tp
;
2875 resume_ptid
= user_visible_resume_ptid (step
);
2877 /* In all-stop mode, delete the per-thread status of all threads
2878 we're about to resume, implicitly and explicitly. */
2879 ALL_NON_EXITED_THREADS (tp
)
2881 if (!ptid_match (tp
->ptid
, resume_ptid
))
2883 clear_proceed_status_thread (tp
);
2887 if (!ptid_equal (inferior_ptid
, null_ptid
))
2889 struct inferior
*inferior
;
2893 /* If in non-stop mode, only delete the per-thread status of
2894 the current thread. */
2895 clear_proceed_status_thread (inferior_thread ());
2898 inferior
= current_inferior ();
2899 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2902 gdb::observers::about_to_proceed
.notify ();
2905 /* Returns true if TP is still stopped at a breakpoint that needs
2906 stepping-over in order to make progress. If the breakpoint is gone
2907 meanwhile, we can skip the whole step-over dance. */
2910 thread_still_needs_step_over_bp (struct thread_info
*tp
)
2912 if (tp
->stepping_over_breakpoint
)
2914 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
2916 if (breakpoint_here_p (regcache
->aspace (),
2917 regcache_read_pc (regcache
))
2918 == ordinary_breakpoint_here
)
2921 tp
->stepping_over_breakpoint
= 0;
2927 /* Check whether thread TP still needs to start a step-over in order
2928 to make progress when resumed. Returns an bitwise or of enum
2929 step_over_what bits, indicating what needs to be stepped over. */
2931 static step_over_what
2932 thread_still_needs_step_over (struct thread_info
*tp
)
2934 step_over_what what
= 0;
2936 if (thread_still_needs_step_over_bp (tp
))
2937 what
|= STEP_OVER_BREAKPOINT
;
2939 if (tp
->stepping_over_watchpoint
2940 && !target_have_steppable_watchpoint
)
2941 what
|= STEP_OVER_WATCHPOINT
;
2946 /* Returns true if scheduler locking applies. STEP indicates whether
2947 we're about to do a step/next-like command to a thread. */
2950 schedlock_applies (struct thread_info
*tp
)
2952 return (scheduler_mode
== schedlock_on
2953 || (scheduler_mode
== schedlock_step
2954 && tp
->control
.stepping_command
)
2955 || (scheduler_mode
== schedlock_replay
2956 && target_record_will_replay (minus_one_ptid
,
2957 execution_direction
)));
2960 /* Basic routine for continuing the program in various fashions.
2962 ADDR is the address to resume at, or -1 for resume where stopped.
2963 SIGGNAL is the signal to give it, or 0 for none,
2964 or -1 for act according to how it stopped.
2965 STEP is nonzero if should trap after one instruction.
2966 -1 means return after that and print nothing.
2967 You should probably set various step_... variables
2968 before calling here, if you are stepping.
2970 You should call clear_proceed_status before calling proceed. */
2973 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
)
2975 struct regcache
*regcache
;
2976 struct gdbarch
*gdbarch
;
2977 struct thread_info
*tp
;
2980 struct execution_control_state ecss
;
2981 struct execution_control_state
*ecs
= &ecss
;
2982 struct cleanup
*old_chain
;
2985 /* If we're stopped at a fork/vfork, follow the branch set by the
2986 "set follow-fork-mode" command; otherwise, we'll just proceed
2987 resuming the current thread. */
2988 if (!follow_fork ())
2990 /* The target for some reason decided not to resume. */
2992 if (target_can_async_p ())
2993 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2997 /* We'll update this if & when we switch to a new thread. */
2998 previous_inferior_ptid
= inferior_ptid
;
3000 regcache
= get_current_regcache ();
3001 gdbarch
= regcache
->arch ();
3002 const address_space
*aspace
= regcache
->aspace ();
3004 pc
= regcache_read_pc (regcache
);
3005 tp
= inferior_thread ();
3007 /* Fill in with reasonable starting values. */
3008 init_thread_stepping_state (tp
);
3010 gdb_assert (!thread_is_in_step_over_chain (tp
));
3012 if (addr
== (CORE_ADDR
) -1)
3015 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
3016 && execution_direction
!= EXEC_REVERSE
)
3017 /* There is a breakpoint at the address we will resume at,
3018 step one instruction before inserting breakpoints so that
3019 we do not stop right away (and report a second hit at this
3022 Note, we don't do this in reverse, because we won't
3023 actually be executing the breakpoint insn anyway.
3024 We'll be (un-)executing the previous instruction. */
3025 tp
->stepping_over_breakpoint
= 1;
3026 else if (gdbarch_single_step_through_delay_p (gdbarch
)
3027 && gdbarch_single_step_through_delay (gdbarch
,
3028 get_current_frame ()))
3029 /* We stepped onto an instruction that needs to be stepped
3030 again before re-inserting the breakpoint, do so. */
3031 tp
->stepping_over_breakpoint
= 1;
3035 regcache_write_pc (regcache
, addr
);
3038 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
3039 tp
->suspend
.stop_signal
= siggnal
;
3041 resume_ptid
= user_visible_resume_ptid (tp
->control
.stepping_command
);
3043 /* If an exception is thrown from this point on, make sure to
3044 propagate GDB's knowledge of the executing state to the
3045 frontend/user running state. */
3046 old_chain
= make_cleanup (finish_thread_state_cleanup
, &resume_ptid
);
3048 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
3049 threads (e.g., we might need to set threads stepping over
3050 breakpoints first), from the user/frontend's point of view, all
3051 threads in RESUME_PTID are now running. Unless we're calling an
3052 inferior function, as in that case we pretend the inferior
3053 doesn't run at all. */
3054 if (!tp
->control
.in_infcall
)
3055 set_running (resume_ptid
, 1);
3058 fprintf_unfiltered (gdb_stdlog
,
3059 "infrun: proceed (addr=%s, signal=%s)\n",
3060 paddress (gdbarch
, addr
),
3061 gdb_signal_to_symbol_string (siggnal
));
3063 annotate_starting ();
3065 /* Make sure that output from GDB appears before output from the
3067 gdb_flush (gdb_stdout
);
3069 /* Since we've marked the inferior running, give it the terminal. A
3070 QUIT/Ctrl-C from here on is forwarded to the target (which can
3071 still detect attempts to unblock a stuck connection with repeated
3072 Ctrl-C from within target_pass_ctrlc). */
3073 target_terminal::inferior ();
3075 /* In a multi-threaded task we may select another thread and
3076 then continue or step.
3078 But if a thread that we're resuming had stopped at a breakpoint,
3079 it will immediately cause another breakpoint stop without any
3080 execution (i.e. it will report a breakpoint hit incorrectly). So
3081 we must step over it first.
3083 Look for threads other than the current (TP) that reported a
3084 breakpoint hit and haven't been resumed yet since. */
3086 /* If scheduler locking applies, we can avoid iterating over all
3088 if (!non_stop
&& !schedlock_applies (tp
))
3090 struct thread_info
*current
= tp
;
3092 ALL_NON_EXITED_THREADS (tp
)
3094 /* Ignore the current thread here. It's handled
3099 /* Ignore threads of processes we're not resuming. */
3100 if (!ptid_match (tp
->ptid
, resume_ptid
))
3103 if (!thread_still_needs_step_over (tp
))
3106 gdb_assert (!thread_is_in_step_over_chain (tp
));
3109 fprintf_unfiltered (gdb_stdlog
,
3110 "infrun: need to step-over [%s] first\n",
3111 target_pid_to_str (tp
->ptid
));
3113 thread_step_over_chain_enqueue (tp
);
3119 /* Enqueue the current thread last, so that we move all other
3120 threads over their breakpoints first. */
3121 if (tp
->stepping_over_breakpoint
)
3122 thread_step_over_chain_enqueue (tp
);
3124 /* If the thread isn't started, we'll still need to set its prev_pc,
3125 so that switch_back_to_stepped_thread knows the thread hasn't
3126 advanced. Must do this before resuming any thread, as in
3127 all-stop/remote, once we resume we can't send any other packet
3128 until the target stops again. */
3129 tp
->prev_pc
= regcache_read_pc (regcache
);
3132 scoped_restore save_defer_tc
= make_scoped_defer_target_commit_resume ();
3134 started
= start_step_over ();
3136 if (step_over_info_valid_p ())
3138 /* Either this thread started a new in-line step over, or some
3139 other thread was already doing one. In either case, don't
3140 resume anything else until the step-over is finished. */
3142 else if (started
&& !target_is_non_stop_p ())
3144 /* A new displaced stepping sequence was started. In all-stop,
3145 we can't talk to the target anymore until it next stops. */
3147 else if (!non_stop
&& target_is_non_stop_p ())
3149 /* In all-stop, but the target is always in non-stop mode.
3150 Start all other threads that are implicitly resumed too. */
3151 ALL_NON_EXITED_THREADS (tp
)
3153 /* Ignore threads of processes we're not resuming. */
3154 if (!ptid_match (tp
->ptid
, resume_ptid
))
3160 fprintf_unfiltered (gdb_stdlog
,
3161 "infrun: proceed: [%s] resumed\n",
3162 target_pid_to_str (tp
->ptid
));
3163 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
3167 if (thread_is_in_step_over_chain (tp
))
3170 fprintf_unfiltered (gdb_stdlog
,
3171 "infrun: proceed: [%s] needs step-over\n",
3172 target_pid_to_str (tp
->ptid
));
3177 fprintf_unfiltered (gdb_stdlog
,
3178 "infrun: proceed: resuming %s\n",
3179 target_pid_to_str (tp
->ptid
));
3181 reset_ecs (ecs
, tp
);
3182 switch_to_thread (tp
->ptid
);
3183 keep_going_pass_signal (ecs
);
3184 if (!ecs
->wait_some_more
)
3185 error (_("Command aborted."));
3188 else if (!tp
->resumed
&& !thread_is_in_step_over_chain (tp
))
3190 /* The thread wasn't started, and isn't queued, run it now. */
3191 reset_ecs (ecs
, tp
);
3192 switch_to_thread (tp
->ptid
);
3193 keep_going_pass_signal (ecs
);
3194 if (!ecs
->wait_some_more
)
3195 error (_("Command aborted."));
3199 target_commit_resume ();
3201 discard_cleanups (old_chain
);
3203 /* Tell the event loop to wait for it to stop. If the target
3204 supports asynchronous execution, it'll do this from within
3206 if (!target_can_async_p ())
3207 mark_async_event_handler (infrun_async_inferior_event_token
);
3211 /* Start remote-debugging of a machine over a serial link. */
3214 start_remote (int from_tty
)
3216 struct inferior
*inferior
;
3218 inferior
= current_inferior ();
3219 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
3221 /* Always go on waiting for the target, regardless of the mode. */
3222 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3223 indicate to wait_for_inferior that a target should timeout if
3224 nothing is returned (instead of just blocking). Because of this,
3225 targets expecting an immediate response need to, internally, set
3226 things up so that the target_wait() is forced to eventually
3228 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3229 differentiate to its caller what the state of the target is after
3230 the initial open has been performed. Here we're assuming that
3231 the target has stopped. It should be possible to eventually have
3232 target_open() return to the caller an indication that the target
3233 is currently running and GDB state should be set to the same as
3234 for an async run. */
3235 wait_for_inferior ();
3237 /* Now that the inferior has stopped, do any bookkeeping like
3238 loading shared libraries. We want to do this before normal_stop,
3239 so that the displayed frame is up to date. */
3240 post_create_inferior (¤t_target
, from_tty
);
3245 /* Initialize static vars when a new inferior begins. */
3248 init_wait_for_inferior (void)
3250 /* These are meaningless until the first time through wait_for_inferior. */
3252 breakpoint_init_inferior (inf_starting
);
3254 clear_proceed_status (0);
3256 target_last_wait_ptid
= minus_one_ptid
;
3258 previous_inferior_ptid
= inferior_ptid
;
3260 /* Discard any skipped inlined frames. */
3261 clear_inline_frame_state (minus_one_ptid
);
3266 static void handle_inferior_event (struct execution_control_state
*ecs
);
3268 static void handle_step_into_function (struct gdbarch
*gdbarch
,
3269 struct execution_control_state
*ecs
);
3270 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
3271 struct execution_control_state
*ecs
);
3272 static void handle_signal_stop (struct execution_control_state
*ecs
);
3273 static void check_exception_resume (struct execution_control_state
*,
3274 struct frame_info
*);
3276 static void end_stepping_range (struct execution_control_state
*ecs
);
3277 static void stop_waiting (struct execution_control_state
*ecs
);
3278 static void keep_going (struct execution_control_state
*ecs
);
3279 static void process_event_stop_test (struct execution_control_state
*ecs
);
3280 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
3282 /* This function is attached as a "thread_stop_requested" observer.
3283 Cleanup local state that assumed the PTID was to be resumed, and
3284 report the stop to the frontend. */
3287 infrun_thread_stop_requested (ptid_t ptid
)
3289 struct thread_info
*tp
;
3291 /* PTID was requested to stop. If the thread was already stopped,
3292 but the user/frontend doesn't know about that yet (e.g., the
3293 thread had been temporarily paused for some step-over), set up
3294 for reporting the stop now. */
3295 ALL_NON_EXITED_THREADS (tp
)
3296 if (ptid_match (tp
->ptid
, ptid
))
3298 if (tp
->state
!= THREAD_RUNNING
)
3303 /* Remove matching threads from the step-over queue, so
3304 start_step_over doesn't try to resume them
3306 if (thread_is_in_step_over_chain (tp
))
3307 thread_step_over_chain_remove (tp
);
3309 /* If the thread is stopped, but the user/frontend doesn't
3310 know about that yet, queue a pending event, as if the
3311 thread had just stopped now. Unless the thread already had
3313 if (!tp
->suspend
.waitstatus_pending_p
)
3315 tp
->suspend
.waitstatus_pending_p
= 1;
3316 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_STOPPED
;
3317 tp
->suspend
.waitstatus
.value
.sig
= GDB_SIGNAL_0
;
3320 /* Clear the inline-frame state, since we're re-processing the
3322 clear_inline_frame_state (tp
->ptid
);
3324 /* If this thread was paused because some other thread was
3325 doing an inline-step over, let that finish first. Once
3326 that happens, we'll restart all threads and consume pending
3327 stop events then. */
3328 if (step_over_info_valid_p ())
3331 /* Otherwise we can process the (new) pending event now. Set
3332 it so this pending event is considered by
3339 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
3341 if (ptid_equal (target_last_wait_ptid
, tp
->ptid
))
3342 nullify_last_target_wait_ptid ();
3345 /* Delete the step resume, single-step and longjmp/exception resume
3346 breakpoints of TP. */
3349 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
3351 delete_step_resume_breakpoint (tp
);
3352 delete_exception_resume_breakpoint (tp
);
3353 delete_single_step_breakpoints (tp
);
3356 /* If the target still has execution, call FUNC for each thread that
3357 just stopped. In all-stop, that's all the non-exited threads; in
3358 non-stop, that's the current thread, only. */
3360 typedef void (*for_each_just_stopped_thread_callback_func
)
3361 (struct thread_info
*tp
);
3364 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
3366 if (!target_has_execution
|| ptid_equal (inferior_ptid
, null_ptid
))
3369 if (target_is_non_stop_p ())
3371 /* If in non-stop mode, only the current thread stopped. */
3372 func (inferior_thread ());
3376 struct thread_info
*tp
;
3378 /* In all-stop mode, all threads have stopped. */
3379 ALL_NON_EXITED_THREADS (tp
)
3386 /* Delete the step resume and longjmp/exception resume breakpoints of
3387 the threads that just stopped. */
3390 delete_just_stopped_threads_infrun_breakpoints (void)
3392 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3395 /* Delete the single-step breakpoints of the threads that just
3399 delete_just_stopped_threads_single_step_breakpoints (void)
3401 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3404 /* A cleanup wrapper. */
3407 delete_just_stopped_threads_infrun_breakpoints_cleanup (void *arg
)
3409 delete_just_stopped_threads_infrun_breakpoints ();
3415 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3416 const struct target_waitstatus
*ws
)
3418 std::string status_string
= target_waitstatus_to_string (ws
);
3421 /* The text is split over several lines because it was getting too long.
3422 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3423 output as a unit; we want only one timestamp printed if debug_timestamp
3426 stb
.printf ("infrun: target_wait (%d.%ld.%ld",
3427 ptid_get_pid (waiton_ptid
),
3428 ptid_get_lwp (waiton_ptid
),
3429 ptid_get_tid (waiton_ptid
));
3430 if (ptid_get_pid (waiton_ptid
) != -1)
3431 stb
.printf (" [%s]", target_pid_to_str (waiton_ptid
));
3432 stb
.printf (", status) =\n");
3433 stb
.printf ("infrun: %d.%ld.%ld [%s],\n",
3434 ptid_get_pid (result_ptid
),
3435 ptid_get_lwp (result_ptid
),
3436 ptid_get_tid (result_ptid
),
3437 target_pid_to_str (result_ptid
));
3438 stb
.printf ("infrun: %s\n", status_string
.c_str ());
3440 /* This uses %s in part to handle %'s in the text, but also to avoid
3441 a gcc error: the format attribute requires a string literal. */
3442 fprintf_unfiltered (gdb_stdlog
, "%s", stb
.c_str ());
3445 /* Select a thread at random, out of those which are resumed and have
3448 static struct thread_info
*
3449 random_pending_event_thread (ptid_t waiton_ptid
)
3451 struct thread_info
*event_tp
;
3453 int random_selector
;
3455 /* First see how many events we have. Count only resumed threads
3456 that have an event pending. */
3457 ALL_NON_EXITED_THREADS (event_tp
)
3458 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3459 && event_tp
->resumed
3460 && event_tp
->suspend
.waitstatus_pending_p
)
3463 if (num_events
== 0)
3466 /* Now randomly pick a thread out of those that have had events. */
3467 random_selector
= (int)
3468 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
3470 if (debug_infrun
&& num_events
> 1)
3471 fprintf_unfiltered (gdb_stdlog
,
3472 "infrun: Found %d events, selecting #%d\n",
3473 num_events
, random_selector
);
3475 /* Select the Nth thread that has had an event. */
3476 ALL_NON_EXITED_THREADS (event_tp
)
3477 if (ptid_match (event_tp
->ptid
, waiton_ptid
)
3478 && event_tp
->resumed
3479 && event_tp
->suspend
.waitstatus_pending_p
)
3480 if (random_selector
-- == 0)
3486 /* Wrapper for target_wait that first checks whether threads have
3487 pending statuses to report before actually asking the target for
3491 do_target_wait (ptid_t ptid
, struct target_waitstatus
*status
, int options
)
3494 struct thread_info
*tp
;
3496 /* First check if there is a resumed thread with a wait status
3498 if (ptid_equal (ptid
, minus_one_ptid
) || ptid_is_pid (ptid
))
3500 tp
= random_pending_event_thread (ptid
);
3505 fprintf_unfiltered (gdb_stdlog
,
3506 "infrun: Waiting for specific thread %s.\n",
3507 target_pid_to_str (ptid
));
3509 /* We have a specific thread to check. */
3510 tp
= find_thread_ptid (ptid
);
3511 gdb_assert (tp
!= NULL
);
3512 if (!tp
->suspend
.waitstatus_pending_p
)
3517 && (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3518 || tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
3520 struct regcache
*regcache
= get_thread_regcache (tp
->ptid
);
3521 struct gdbarch
*gdbarch
= regcache
->arch ();
3525 pc
= regcache_read_pc (regcache
);
3527 if (pc
!= tp
->suspend
.stop_pc
)
3530 fprintf_unfiltered (gdb_stdlog
,
3531 "infrun: PC of %s changed. was=%s, now=%s\n",
3532 target_pid_to_str (tp
->ptid
),
3533 paddress (gdbarch
, tp
->prev_pc
),
3534 paddress (gdbarch
, pc
));
3537 else if (!breakpoint_inserted_here_p (regcache
->aspace (), pc
))
3540 fprintf_unfiltered (gdb_stdlog
,
3541 "infrun: previous breakpoint of %s, at %s gone\n",
3542 target_pid_to_str (tp
->ptid
),
3543 paddress (gdbarch
, pc
));
3551 fprintf_unfiltered (gdb_stdlog
,
3552 "infrun: pending event of %s cancelled.\n",
3553 target_pid_to_str (tp
->ptid
));
3555 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_SPURIOUS
;
3556 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3565 = target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
3567 fprintf_unfiltered (gdb_stdlog
,
3568 "infrun: Using pending wait status %s for %s.\n",
3570 target_pid_to_str (tp
->ptid
));
3573 /* Now that we've selected our final event LWP, un-adjust its PC
3574 if it was a software breakpoint (and the target doesn't
3575 always adjust the PC itself). */
3576 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3577 && !target_supports_stopped_by_sw_breakpoint ())
3579 struct regcache
*regcache
;
3580 struct gdbarch
*gdbarch
;
3583 regcache
= get_thread_regcache (tp
->ptid
);
3584 gdbarch
= regcache
->arch ();
3586 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3591 pc
= regcache_read_pc (regcache
);
3592 regcache_write_pc (regcache
, pc
+ decr_pc
);
3596 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3597 *status
= tp
->suspend
.waitstatus
;
3598 tp
->suspend
.waitstatus_pending_p
= 0;
3600 /* Wake up the event loop again, until all pending events are
3602 if (target_is_async_p ())
3603 mark_async_event_handler (infrun_async_inferior_event_token
);
3607 /* But if we don't find one, we'll have to wait. */
3609 if (deprecated_target_wait_hook
)
3610 event_ptid
= deprecated_target_wait_hook (ptid
, status
, options
);
3612 event_ptid
= target_wait (ptid
, status
, options
);
3617 /* Prepare and stabilize the inferior for detaching it. E.g.,
3618 detaching while a thread is displaced stepping is a recipe for
3619 crashing it, as nothing would readjust the PC out of the scratch
3623 prepare_for_detach (void)
3625 struct inferior
*inf
= current_inferior ();
3626 ptid_t pid_ptid
= pid_to_ptid (inf
->pid
);
3627 struct displaced_step_inferior_state
*displaced
;
3629 displaced
= get_displaced_stepping_state (inf
->pid
);
3631 /* Is any thread of this process displaced stepping? If not,
3632 there's nothing else to do. */
3633 if (displaced
== NULL
|| ptid_equal (displaced
->step_ptid
, null_ptid
))
3637 fprintf_unfiltered (gdb_stdlog
,
3638 "displaced-stepping in-process while detaching");
3640 scoped_restore restore_detaching
= make_scoped_restore (&inf
->detaching
, true);
3642 while (!ptid_equal (displaced
->step_ptid
, null_ptid
))
3644 struct cleanup
*old_chain_2
;
3645 struct execution_control_state ecss
;
3646 struct execution_control_state
*ecs
;
3649 memset (ecs
, 0, sizeof (*ecs
));
3651 overlay_cache_invalid
= 1;
3652 /* Flush target cache before starting to handle each event.
3653 Target was running and cache could be stale. This is just a
3654 heuristic. Running threads may modify target memory, but we
3655 don't get any event. */
3656 target_dcache_invalidate ();
3658 ecs
->ptid
= do_target_wait (pid_ptid
, &ecs
->ws
, 0);
3661 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
3663 /* If an error happens while handling the event, propagate GDB's
3664 knowledge of the executing state to the frontend/user running
3666 old_chain_2
= make_cleanup (finish_thread_state_cleanup
,
3669 /* Now figure out what to do with the result of the result. */
3670 handle_inferior_event (ecs
);
3672 /* No error, don't finish the state yet. */
3673 discard_cleanups (old_chain_2
);
3675 /* Breakpoints and watchpoints are not installed on the target
3676 at this point, and signals are passed directly to the
3677 inferior, so this must mean the process is gone. */
3678 if (!ecs
->wait_some_more
)
3680 restore_detaching
.release ();
3681 error (_("Program exited while detaching"));
3685 restore_detaching
.release ();
3688 /* Wait for control to return from inferior to debugger.
3690 If inferior gets a signal, we may decide to start it up again
3691 instead of returning. That is why there is a loop in this function.
3692 When this function actually returns it means the inferior
3693 should be left stopped and GDB should read more commands. */
3696 wait_for_inferior (void)
3698 struct cleanup
*old_cleanups
;
3699 struct cleanup
*thread_state_chain
;
3703 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
3706 = make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
,
3709 /* If an error happens while handling the event, propagate GDB's
3710 knowledge of the executing state to the frontend/user running
3712 thread_state_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3716 struct execution_control_state ecss
;
3717 struct execution_control_state
*ecs
= &ecss
;
3718 ptid_t waiton_ptid
= minus_one_ptid
;
3720 memset (ecs
, 0, sizeof (*ecs
));
3722 overlay_cache_invalid
= 1;
3724 /* Flush target cache before starting to handle each event.
3725 Target was running and cache could be stale. This is just a
3726 heuristic. Running threads may modify target memory, but we
3727 don't get any event. */
3728 target_dcache_invalidate ();
3730 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
, 0);
3733 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3735 /* Now figure out what to do with the result of the result. */
3736 handle_inferior_event (ecs
);
3738 if (!ecs
->wait_some_more
)
3742 /* No error, don't finish the state yet. */
3743 discard_cleanups (thread_state_chain
);
3745 do_cleanups (old_cleanups
);
3748 /* Cleanup that reinstalls the readline callback handler, if the
3749 target is running in the background. If while handling the target
3750 event something triggered a secondary prompt, like e.g., a
3751 pagination prompt, we'll have removed the callback handler (see
3752 gdb_readline_wrapper_line). Need to do this as we go back to the
3753 event loop, ready to process further input. Note this has no
3754 effect if the handler hasn't actually been removed, because calling
3755 rl_callback_handler_install resets the line buffer, thus losing
3759 reinstall_readline_callback_handler_cleanup (void *arg
)
3761 struct ui
*ui
= current_ui
;
3765 /* We're not going back to the top level event loop yet. Don't
3766 install the readline callback, as it'd prep the terminal,
3767 readline-style (raw, noecho) (e.g., --batch). We'll install
3768 it the next time the prompt is displayed, when we're ready
3773 if (ui
->command_editing
&& ui
->prompt_state
!= PROMPT_BLOCKED
)
3774 gdb_rl_callback_handler_reinstall ();
3777 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3778 that's just the event thread. In all-stop, that's all threads. */
3781 clean_up_just_stopped_threads_fsms (struct execution_control_state
*ecs
)
3783 struct thread_info
*thr
= ecs
->event_thread
;
3785 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3786 thread_fsm_clean_up (thr
->thread_fsm
, thr
);
3790 ALL_NON_EXITED_THREADS (thr
)
3792 if (thr
->thread_fsm
== NULL
)
3794 if (thr
== ecs
->event_thread
)
3797 switch_to_thread (thr
->ptid
);
3798 thread_fsm_clean_up (thr
->thread_fsm
, thr
);
3801 if (ecs
->event_thread
!= NULL
)
3802 switch_to_thread (ecs
->event_thread
->ptid
);
3806 /* Helper for all_uis_check_sync_execution_done that works on the
3810 check_curr_ui_sync_execution_done (void)
3812 struct ui
*ui
= current_ui
;
3814 if (ui
->prompt_state
== PROMPT_NEEDED
3816 && !gdb_in_secondary_prompt_p (ui
))
3818 target_terminal::ours ();
3819 gdb::observers::sync_execution_done
.notify ();
3820 ui_register_input_event_handler (ui
);
3827 all_uis_check_sync_execution_done (void)
3829 SWITCH_THRU_ALL_UIS ()
3831 check_curr_ui_sync_execution_done ();
3838 all_uis_on_sync_execution_starting (void)
3840 SWITCH_THRU_ALL_UIS ()
3842 if (current_ui
->prompt_state
== PROMPT_NEEDED
)
3843 async_disable_stdin ();
3847 /* Asynchronous version of wait_for_inferior. It is called by the
3848 event loop whenever a change of state is detected on the file
3849 descriptor corresponding to the target. It can be called more than
3850 once to complete a single execution command. In such cases we need
3851 to keep the state in a global variable ECSS. If it is the last time
3852 that this function is called for a single execution command, then
3853 report to the user that the inferior has stopped, and do the
3854 necessary cleanups. */
3857 fetch_inferior_event (void *client_data
)
3859 struct execution_control_state ecss
;
3860 struct execution_control_state
*ecs
= &ecss
;
3861 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
3862 struct cleanup
*ts_old_chain
;
3864 ptid_t waiton_ptid
= minus_one_ptid
;
3866 memset (ecs
, 0, sizeof (*ecs
));
3868 /* Events are always processed with the main UI as current UI. This
3869 way, warnings, debug output, etc. are always consistently sent to
3870 the main console. */
3871 scoped_restore save_ui
= make_scoped_restore (¤t_ui
, main_ui
);
3873 /* End up with readline processing input, if necessary. */
3874 make_cleanup (reinstall_readline_callback_handler_cleanup
, NULL
);
3876 /* We're handling a live event, so make sure we're doing live
3877 debugging. If we're looking at traceframes while the target is
3878 running, we're going to need to get back to that mode after
3879 handling the event. */
3880 gdb::optional
<scoped_restore_current_traceframe
> maybe_restore_traceframe
;
3883 maybe_restore_traceframe
.emplace ();
3884 set_current_traceframe (-1);
3887 gdb::optional
<scoped_restore_current_thread
> maybe_restore_thread
;
3890 /* In non-stop mode, the user/frontend should not notice a thread
3891 switch due to internal events. Make sure we reverse to the
3892 user selected thread and frame after handling the event and
3893 running any breakpoint commands. */
3894 maybe_restore_thread
.emplace ();
3896 overlay_cache_invalid
= 1;
3897 /* Flush target cache before starting to handle each event. Target
3898 was running and cache could be stale. This is just a heuristic.
3899 Running threads may modify target memory, but we don't get any
3901 target_dcache_invalidate ();
3903 scoped_restore save_exec_dir
3904 = make_scoped_restore (&execution_direction
, target_execution_direction ());
3906 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
,
3907 target_can_async_p () ? TARGET_WNOHANG
: 0);
3910 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3912 /* If an error happens while handling the event, propagate GDB's
3913 knowledge of the executing state to the frontend/user running
3915 if (!target_is_non_stop_p ())
3916 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
3918 ts_old_chain
= make_cleanup (finish_thread_state_cleanup
, &ecs
->ptid
);
3920 /* Get executed before make_cleanup_restore_current_thread above to apply
3921 still for the thread which has thrown the exception. */
3922 make_bpstat_clear_actions_cleanup ();
3924 make_cleanup (delete_just_stopped_threads_infrun_breakpoints_cleanup
, NULL
);
3926 /* Now figure out what to do with the result of the result. */
3927 handle_inferior_event (ecs
);
3929 if (!ecs
->wait_some_more
)
3931 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
3932 int should_stop
= 1;
3933 struct thread_info
*thr
= ecs
->event_thread
;
3934 int should_notify_stop
= 1;
3936 delete_just_stopped_threads_infrun_breakpoints ();
3940 struct thread_fsm
*thread_fsm
= thr
->thread_fsm
;
3942 if (thread_fsm
!= NULL
)
3943 should_stop
= thread_fsm_should_stop (thread_fsm
, thr
);
3952 clean_up_just_stopped_threads_fsms (ecs
);
3954 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3957 = thread_fsm_should_notify_stop (thr
->thread_fsm
);
3960 if (should_notify_stop
)
3964 /* We may not find an inferior if this was a process exit. */
3965 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
3966 proceeded
= normal_stop ();
3970 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3977 /* No error, don't finish the thread states yet. */
3978 discard_cleanups (ts_old_chain
);
3980 /* Revert thread and frame. */
3981 do_cleanups (old_chain
);
3983 /* If a UI was in sync execution mode, and now isn't, restore its
3984 prompt (a synchronous execution command has finished, and we're
3985 ready for input). */
3986 all_uis_check_sync_execution_done ();
3989 && exec_done_display_p
3990 && (ptid_equal (inferior_ptid
, null_ptid
)
3991 || !is_running (inferior_ptid
)))
3992 printf_unfiltered (_("completed.\n"));
3995 /* Record the frame and location we're currently stepping through. */
3997 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
3999 struct thread_info
*tp
= inferior_thread ();
4001 tp
->control
.step_frame_id
= get_frame_id (frame
);
4002 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
4004 tp
->current_symtab
= sal
.symtab
;
4005 tp
->current_line
= sal
.line
;
4008 /* Clear context switchable stepping state. */
4011 init_thread_stepping_state (struct thread_info
*tss
)
4013 tss
->stepped_breakpoint
= 0;
4014 tss
->stepping_over_breakpoint
= 0;
4015 tss
->stepping_over_watchpoint
= 0;
4016 tss
->step_after_step_resume_breakpoint
= 0;
4019 /* Set the cached copy of the last ptid/waitstatus. */
4022 set_last_target_status (ptid_t ptid
, struct target_waitstatus status
)
4024 target_last_wait_ptid
= ptid
;
4025 target_last_waitstatus
= status
;
4028 /* Return the cached copy of the last pid/waitstatus returned by
4029 target_wait()/deprecated_target_wait_hook(). The data is actually
4030 cached by handle_inferior_event(), which gets called immediately
4031 after target_wait()/deprecated_target_wait_hook(). */
4034 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
4036 *ptidp
= target_last_wait_ptid
;
4037 *status
= target_last_waitstatus
;
4041 nullify_last_target_wait_ptid (void)
4043 target_last_wait_ptid
= minus_one_ptid
;
4046 /* Switch thread contexts. */
4049 context_switch (ptid_t ptid
)
4051 if (debug_infrun
&& !ptid_equal (ptid
, inferior_ptid
))
4053 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
4054 target_pid_to_str (inferior_ptid
));
4055 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
4056 target_pid_to_str (ptid
));
4059 switch_to_thread (ptid
);
4062 /* If the target can't tell whether we've hit breakpoints
4063 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
4064 check whether that could have been caused by a breakpoint. If so,
4065 adjust the PC, per gdbarch_decr_pc_after_break. */
4068 adjust_pc_after_break (struct thread_info
*thread
,
4069 struct target_waitstatus
*ws
)
4071 struct regcache
*regcache
;
4072 struct gdbarch
*gdbarch
;
4073 CORE_ADDR breakpoint_pc
, decr_pc
;
4075 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
4076 we aren't, just return.
4078 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
4079 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
4080 implemented by software breakpoints should be handled through the normal
4083 NOTE drow/2004-01-31: On some targets, breakpoints may generate
4084 different signals (SIGILL or SIGEMT for instance), but it is less
4085 clear where the PC is pointing afterwards. It may not match
4086 gdbarch_decr_pc_after_break. I don't know any specific target that
4087 generates these signals at breakpoints (the code has been in GDB since at
4088 least 1992) so I can not guess how to handle them here.
4090 In earlier versions of GDB, a target with
4091 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
4092 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
4093 target with both of these set in GDB history, and it seems unlikely to be
4094 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
4096 if (ws
->kind
!= TARGET_WAITKIND_STOPPED
)
4099 if (ws
->value
.sig
!= GDB_SIGNAL_TRAP
)
4102 /* In reverse execution, when a breakpoint is hit, the instruction
4103 under it has already been de-executed. The reported PC always
4104 points at the breakpoint address, so adjusting it further would
4105 be wrong. E.g., consider this case on a decr_pc_after_break == 1
4108 B1 0x08000000 : INSN1
4109 B2 0x08000001 : INSN2
4111 PC -> 0x08000003 : INSN4
4113 Say you're stopped at 0x08000003 as above. Reverse continuing
4114 from that point should hit B2 as below. Reading the PC when the
4115 SIGTRAP is reported should read 0x08000001 and INSN2 should have
4116 been de-executed already.
4118 B1 0x08000000 : INSN1
4119 B2 PC -> 0x08000001 : INSN2
4123 We can't apply the same logic as for forward execution, because
4124 we would wrongly adjust the PC to 0x08000000, since there's a
4125 breakpoint at PC - 1. We'd then report a hit on B1, although
4126 INSN1 hadn't been de-executed yet. Doing nothing is the correct
4128 if (execution_direction
== EXEC_REVERSE
)
4131 /* If the target can tell whether the thread hit a SW breakpoint,
4132 trust it. Targets that can tell also adjust the PC
4134 if (target_supports_stopped_by_sw_breakpoint ())
4137 /* Note that relying on whether a breakpoint is planted in memory to
4138 determine this can fail. E.g,. the breakpoint could have been
4139 removed since. Or the thread could have been told to step an
4140 instruction the size of a breakpoint instruction, and only
4141 _after_ was a breakpoint inserted at its address. */
4143 /* If this target does not decrement the PC after breakpoints, then
4144 we have nothing to do. */
4145 regcache
= get_thread_regcache (thread
->ptid
);
4146 gdbarch
= regcache
->arch ();
4148 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
4152 const address_space
*aspace
= regcache
->aspace ();
4154 /* Find the location where (if we've hit a breakpoint) the
4155 breakpoint would be. */
4156 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
4158 /* If the target can't tell whether a software breakpoint triggered,
4159 fallback to figuring it out based on breakpoints we think were
4160 inserted in the target, and on whether the thread was stepped or
4163 /* Check whether there actually is a software breakpoint inserted at
4166 If in non-stop mode, a race condition is possible where we've
4167 removed a breakpoint, but stop events for that breakpoint were
4168 already queued and arrive later. To suppress those spurious
4169 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
4170 and retire them after a number of stop events are reported. Note
4171 this is an heuristic and can thus get confused. The real fix is
4172 to get the "stopped by SW BP and needs adjustment" info out of
4173 the target/kernel (and thus never reach here; see above). */
4174 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
4175 || (target_is_non_stop_p ()
4176 && moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
4178 gdb::optional
<scoped_restore_tmpl
<int>> restore_operation_disable
;
4180 if (record_full_is_used ())
4181 restore_operation_disable
.emplace
4182 (record_full_gdb_operation_disable_set ());
4184 /* When using hardware single-step, a SIGTRAP is reported for both
4185 a completed single-step and a software breakpoint. Need to
4186 differentiate between the two, as the latter needs adjusting
4187 but the former does not.
4189 The SIGTRAP can be due to a completed hardware single-step only if
4190 - we didn't insert software single-step breakpoints
4191 - this thread is currently being stepped
4193 If any of these events did not occur, we must have stopped due
4194 to hitting a software breakpoint, and have to back up to the
4197 As a special case, we could have hardware single-stepped a
4198 software breakpoint. In this case (prev_pc == breakpoint_pc),
4199 we also need to back up to the breakpoint address. */
4201 if (thread_has_single_step_breakpoints_set (thread
)
4202 || !currently_stepping (thread
)
4203 || (thread
->stepped_breakpoint
4204 && thread
->prev_pc
== breakpoint_pc
))
4205 regcache_write_pc (regcache
, breakpoint_pc
);
4210 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
4212 for (frame
= get_prev_frame (frame
);
4214 frame
= get_prev_frame (frame
))
4216 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
4218 if (get_frame_type (frame
) != INLINE_FRAME
)
4225 /* If the event thread has the stop requested flag set, pretend it
4226 stopped for a GDB_SIGNAL_0 (i.e., as if it stopped due to
4230 handle_stop_requested (struct execution_control_state
*ecs
)
4232 if (ecs
->event_thread
->stop_requested
)
4234 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
4235 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
4236 handle_signal_stop (ecs
);
4242 /* Auxiliary function that handles syscall entry/return events.
4243 It returns 1 if the inferior should keep going (and GDB
4244 should ignore the event), or 0 if the event deserves to be
4248 handle_syscall_event (struct execution_control_state
*ecs
)
4250 struct regcache
*regcache
;
4253 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4254 context_switch (ecs
->ptid
);
4256 regcache
= get_thread_regcache (ecs
->ptid
);
4257 syscall_number
= ecs
->ws
.value
.syscall_number
;
4258 stop_pc
= regcache_read_pc (regcache
);
4260 if (catch_syscall_enabled () > 0
4261 && catching_syscall_number (syscall_number
) > 0)
4264 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
4267 ecs
->event_thread
->control
.stop_bpstat
4268 = bpstat_stop_status (regcache
->aspace (),
4269 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4271 if (handle_stop_requested (ecs
))
4274 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4276 /* Catchpoint hit. */
4281 if (handle_stop_requested (ecs
))
4284 /* If no catchpoint triggered for this, then keep going. */
4289 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4292 fill_in_stop_func (struct gdbarch
*gdbarch
,
4293 struct execution_control_state
*ecs
)
4295 if (!ecs
->stop_func_filled_in
)
4297 /* Don't care about return value; stop_func_start and stop_func_name
4298 will both be 0 if it doesn't work. */
4299 find_pc_partial_function (stop_pc
, &ecs
->stop_func_name
,
4300 &ecs
->stop_func_start
, &ecs
->stop_func_end
);
4301 ecs
->stop_func_start
4302 += gdbarch_deprecated_function_start_offset (gdbarch
);
4304 if (gdbarch_skip_entrypoint_p (gdbarch
))
4305 ecs
->stop_func_start
= gdbarch_skip_entrypoint (gdbarch
,
4306 ecs
->stop_func_start
);
4308 ecs
->stop_func_filled_in
= 1;
4313 /* Return the STOP_SOON field of the inferior pointed at by PTID. */
4315 static enum stop_kind
4316 get_inferior_stop_soon (ptid_t ptid
)
4318 struct inferior
*inf
= find_inferior_ptid (ptid
);
4320 gdb_assert (inf
!= NULL
);
4321 return inf
->control
.stop_soon
;
4324 /* Wait for one event. Store the resulting waitstatus in WS, and
4325 return the event ptid. */
4328 wait_one (struct target_waitstatus
*ws
)
4331 ptid_t wait_ptid
= minus_one_ptid
;
4333 overlay_cache_invalid
= 1;
4335 /* Flush target cache before starting to handle each event.
4336 Target was running and cache could be stale. This is just a
4337 heuristic. Running threads may modify target memory, but we
4338 don't get any event. */
4339 target_dcache_invalidate ();
4341 if (deprecated_target_wait_hook
)
4342 event_ptid
= deprecated_target_wait_hook (wait_ptid
, ws
, 0);
4344 event_ptid
= target_wait (wait_ptid
, ws
, 0);
4347 print_target_wait_results (wait_ptid
, event_ptid
, ws
);
4352 /* Generate a wrapper for target_stopped_by_REASON that works on PTID
4353 instead of the current thread. */
4354 #define THREAD_STOPPED_BY(REASON) \
4356 thread_stopped_by_ ## REASON (ptid_t ptid) \
4358 scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid); \
4359 inferior_ptid = ptid; \
4361 return target_stopped_by_ ## REASON (); \
4364 /* Generate thread_stopped_by_watchpoint. */
4365 THREAD_STOPPED_BY (watchpoint
)
4366 /* Generate thread_stopped_by_sw_breakpoint. */
4367 THREAD_STOPPED_BY (sw_breakpoint
)
4368 /* Generate thread_stopped_by_hw_breakpoint. */
4369 THREAD_STOPPED_BY (hw_breakpoint
)
4371 /* Cleanups that switches to the PTID pointed at by PTID_P. */
4374 switch_to_thread_cleanup (void *ptid_p
)
4376 ptid_t ptid
= *(ptid_t
*) ptid_p
;
4378 switch_to_thread (ptid
);
4381 /* Save the thread's event and stop reason to process it later. */
4384 save_waitstatus (struct thread_info
*tp
, struct target_waitstatus
*ws
)
4386 struct regcache
*regcache
;
4390 std::string statstr
= target_waitstatus_to_string (ws
);
4392 fprintf_unfiltered (gdb_stdlog
,
4393 "infrun: saving status %s for %d.%ld.%ld\n",
4395 ptid_get_pid (tp
->ptid
),
4396 ptid_get_lwp (tp
->ptid
),
4397 ptid_get_tid (tp
->ptid
));
4400 /* Record for later. */
4401 tp
->suspend
.waitstatus
= *ws
;
4402 tp
->suspend
.waitstatus_pending_p
= 1;
4404 regcache
= get_thread_regcache (tp
->ptid
);
4405 const address_space
*aspace
= regcache
->aspace ();
4407 if (ws
->kind
== TARGET_WAITKIND_STOPPED
4408 && ws
->value
.sig
== GDB_SIGNAL_TRAP
)
4410 CORE_ADDR pc
= regcache_read_pc (regcache
);
4412 adjust_pc_after_break (tp
, &tp
->suspend
.waitstatus
);
4414 if (thread_stopped_by_watchpoint (tp
->ptid
))
4416 tp
->suspend
.stop_reason
4417 = TARGET_STOPPED_BY_WATCHPOINT
;
4419 else if (target_supports_stopped_by_sw_breakpoint ()
4420 && thread_stopped_by_sw_breakpoint (tp
->ptid
))
4422 tp
->suspend
.stop_reason
4423 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4425 else if (target_supports_stopped_by_hw_breakpoint ()
4426 && thread_stopped_by_hw_breakpoint (tp
->ptid
))
4428 tp
->suspend
.stop_reason
4429 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4431 else if (!target_supports_stopped_by_hw_breakpoint ()
4432 && hardware_breakpoint_inserted_here_p (aspace
,
4435 tp
->suspend
.stop_reason
4436 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4438 else if (!target_supports_stopped_by_sw_breakpoint ()
4439 && software_breakpoint_inserted_here_p (aspace
,
4442 tp
->suspend
.stop_reason
4443 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4445 else if (!thread_has_single_step_breakpoints_set (tp
)
4446 && currently_stepping (tp
))
4448 tp
->suspend
.stop_reason
4449 = TARGET_STOPPED_BY_SINGLE_STEP
;
4454 /* A cleanup that disables thread create/exit events. */
4457 disable_thread_events (void *arg
)
4459 target_thread_events (0);
4465 stop_all_threads (void)
4467 /* We may need multiple passes to discover all threads. */
4471 struct cleanup
*old_chain
;
4473 gdb_assert (target_is_non_stop_p ());
4476 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads\n");
4478 entry_ptid
= inferior_ptid
;
4479 old_chain
= make_cleanup (switch_to_thread_cleanup
, &entry_ptid
);
4481 target_thread_events (1);
4482 make_cleanup (disable_thread_events
, NULL
);
4484 /* Request threads to stop, and then wait for the stops. Because
4485 threads we already know about can spawn more threads while we're
4486 trying to stop them, and we only learn about new threads when we
4487 update the thread list, do this in a loop, and keep iterating
4488 until two passes find no threads that need to be stopped. */
4489 for (pass
= 0; pass
< 2; pass
++, iterations
++)
4492 fprintf_unfiltered (gdb_stdlog
,
4493 "infrun: stop_all_threads, pass=%d, "
4494 "iterations=%d\n", pass
, iterations
);
4498 struct target_waitstatus ws
;
4500 struct thread_info
*t
;
4502 update_thread_list ();
4504 /* Go through all threads looking for threads that we need
4505 to tell the target to stop. */
4506 ALL_NON_EXITED_THREADS (t
)
4510 /* If already stopping, don't request a stop again.
4511 We just haven't seen the notification yet. */
4512 if (!t
->stop_requested
)
4515 fprintf_unfiltered (gdb_stdlog
,
4516 "infrun: %s executing, "
4518 target_pid_to_str (t
->ptid
));
4519 target_stop (t
->ptid
);
4520 t
->stop_requested
= 1;
4525 fprintf_unfiltered (gdb_stdlog
,
4526 "infrun: %s executing, "
4527 "already stopping\n",
4528 target_pid_to_str (t
->ptid
));
4531 if (t
->stop_requested
)
4537 fprintf_unfiltered (gdb_stdlog
,
4538 "infrun: %s not executing\n",
4539 target_pid_to_str (t
->ptid
));
4541 /* The thread may be not executing, but still be
4542 resumed with a pending status to process. */
4550 /* If we find new threads on the second iteration, restart
4551 over. We want to see two iterations in a row with all
4556 event_ptid
= wait_one (&ws
);
4557 if (ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4559 /* All resumed threads exited. */
4561 else if (ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
4562 || ws
.kind
== TARGET_WAITKIND_EXITED
4563 || ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
4567 ptid_t ptid
= pid_to_ptid (ws
.value
.integer
);
4569 fprintf_unfiltered (gdb_stdlog
,
4570 "infrun: %s exited while "
4571 "stopping threads\n",
4572 target_pid_to_str (ptid
));
4577 struct inferior
*inf
;
4579 t
= find_thread_ptid (event_ptid
);
4581 t
= add_thread (event_ptid
);
4583 t
->stop_requested
= 0;
4586 t
->control
.may_range_step
= 0;
4588 /* This may be the first time we see the inferior report
4590 inf
= find_inferior_ptid (event_ptid
);
4591 if (inf
->needs_setup
)
4593 switch_to_thread_no_regs (t
);
4597 if (ws
.kind
== TARGET_WAITKIND_STOPPED
4598 && ws
.value
.sig
== GDB_SIGNAL_0
)
4600 /* We caught the event that we intended to catch, so
4601 there's no event pending. */
4602 t
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
4603 t
->suspend
.waitstatus_pending_p
= 0;
4605 if (displaced_step_fixup (t
->ptid
, GDB_SIGNAL_0
) < 0)
4607 /* Add it back to the step-over queue. */
4610 fprintf_unfiltered (gdb_stdlog
,
4611 "infrun: displaced-step of %s "
4612 "canceled: adding back to the "
4613 "step-over queue\n",
4614 target_pid_to_str (t
->ptid
));
4616 t
->control
.trap_expected
= 0;
4617 thread_step_over_chain_enqueue (t
);
4622 enum gdb_signal sig
;
4623 struct regcache
*regcache
;
4627 std::string statstr
= target_waitstatus_to_string (&ws
);
4629 fprintf_unfiltered (gdb_stdlog
,
4630 "infrun: target_wait %s, saving "
4631 "status for %d.%ld.%ld\n",
4633 ptid_get_pid (t
->ptid
),
4634 ptid_get_lwp (t
->ptid
),
4635 ptid_get_tid (t
->ptid
));
4638 /* Record for later. */
4639 save_waitstatus (t
, &ws
);
4641 sig
= (ws
.kind
== TARGET_WAITKIND_STOPPED
4642 ? ws
.value
.sig
: GDB_SIGNAL_0
);
4644 if (displaced_step_fixup (t
->ptid
, sig
) < 0)
4646 /* Add it back to the step-over queue. */
4647 t
->control
.trap_expected
= 0;
4648 thread_step_over_chain_enqueue (t
);
4651 regcache
= get_thread_regcache (t
->ptid
);
4652 t
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4656 fprintf_unfiltered (gdb_stdlog
,
4657 "infrun: saved stop_pc=%s for %s "
4658 "(currently_stepping=%d)\n",
4659 paddress (target_gdbarch (),
4660 t
->suspend
.stop_pc
),
4661 target_pid_to_str (t
->ptid
),
4662 currently_stepping (t
));
4669 do_cleanups (old_chain
);
4672 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads done\n");
4675 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
4678 handle_no_resumed (struct execution_control_state
*ecs
)
4680 struct inferior
*inf
;
4681 struct thread_info
*thread
;
4683 if (target_can_async_p ())
4690 if (ui
->prompt_state
== PROMPT_BLOCKED
)
4698 /* There were no unwaited-for children left in the target, but,
4699 we're not synchronously waiting for events either. Just
4703 fprintf_unfiltered (gdb_stdlog
,
4704 "infrun: TARGET_WAITKIND_NO_RESUMED "
4705 "(ignoring: bg)\n");
4706 prepare_to_wait (ecs
);
4711 /* Otherwise, if we were running a synchronous execution command, we
4712 may need to cancel it and give the user back the terminal.
4714 In non-stop mode, the target can't tell whether we've already
4715 consumed previous stop events, so it can end up sending us a
4716 no-resumed event like so:
4718 #0 - thread 1 is left stopped
4720 #1 - thread 2 is resumed and hits breakpoint
4721 -> TARGET_WAITKIND_STOPPED
4723 #2 - thread 3 is resumed and exits
4724 this is the last resumed thread, so
4725 -> TARGET_WAITKIND_NO_RESUMED
4727 #3 - gdb processes stop for thread 2 and decides to re-resume
4730 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
4731 thread 2 is now resumed, so the event should be ignored.
4733 IOW, if the stop for thread 2 doesn't end a foreground command,
4734 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
4735 event. But it could be that the event meant that thread 2 itself
4736 (or whatever other thread was the last resumed thread) exited.
4738 To address this we refresh the thread list and check whether we
4739 have resumed threads _now_. In the example above, this removes
4740 thread 3 from the thread list. If thread 2 was re-resumed, we
4741 ignore this event. If we find no thread resumed, then we cancel
4742 the synchronous command show "no unwaited-for " to the user. */
4743 update_thread_list ();
4745 ALL_NON_EXITED_THREADS (thread
)
4747 if (thread
->executing
4748 || thread
->suspend
.waitstatus_pending_p
)
4750 /* There were no unwaited-for children left in the target at
4751 some point, but there are now. Just ignore. */
4753 fprintf_unfiltered (gdb_stdlog
,
4754 "infrun: TARGET_WAITKIND_NO_RESUMED "
4755 "(ignoring: found resumed)\n");
4756 prepare_to_wait (ecs
);
4761 /* Note however that we may find no resumed thread because the whole
4762 process exited meanwhile (thus updating the thread list results
4763 in an empty thread list). In this case we know we'll be getting
4764 a process exit event shortly. */
4770 thread
= any_live_thread_of_process (inf
->pid
);
4774 fprintf_unfiltered (gdb_stdlog
,
4775 "infrun: TARGET_WAITKIND_NO_RESUMED "
4776 "(expect process exit)\n");
4777 prepare_to_wait (ecs
);
4782 /* Go ahead and report the event. */
4786 /* Given an execution control state that has been freshly filled in by
4787 an event from the inferior, figure out what it means and take
4790 The alternatives are:
4792 1) stop_waiting and return; to really stop and return to the
4795 2) keep_going and return; to wait for the next event (set
4796 ecs->event_thread->stepping_over_breakpoint to 1 to single step
4800 handle_inferior_event_1 (struct execution_control_state
*ecs
)
4802 enum stop_kind stop_soon
;
4804 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
4806 /* We had an event in the inferior, but we are not interested in
4807 handling it at this level. The lower layers have already
4808 done what needs to be done, if anything.
4810 One of the possible circumstances for this is when the
4811 inferior produces output for the console. The inferior has
4812 not stopped, and we are ignoring the event. Another possible
4813 circumstance is any event which the lower level knows will be
4814 reported multiple times without an intervening resume. */
4816 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
4817 prepare_to_wait (ecs
);
4821 if (ecs
->ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
)
4824 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_THREAD_EXITED\n");
4825 prepare_to_wait (ecs
);
4829 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
4830 && handle_no_resumed (ecs
))
4833 /* Cache the last pid/waitstatus. */
4834 set_last_target_status (ecs
->ptid
, ecs
->ws
);
4836 /* Always clear state belonging to the previous time we stopped. */
4837 stop_stack_dummy
= STOP_NONE
;
4839 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4841 /* No unwaited-for children left. IOW, all resumed children
4844 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
4846 stop_print_frame
= 0;
4851 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
4852 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
4854 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
4855 /* If it's a new thread, add it to the thread database. */
4856 if (ecs
->event_thread
== NULL
)
4857 ecs
->event_thread
= add_thread (ecs
->ptid
);
4859 /* Disable range stepping. If the next step request could use a
4860 range, this will be end up re-enabled then. */
4861 ecs
->event_thread
->control
.may_range_step
= 0;
4864 /* Dependent on valid ECS->EVENT_THREAD. */
4865 adjust_pc_after_break (ecs
->event_thread
, &ecs
->ws
);
4867 /* Dependent on the current PC value modified by adjust_pc_after_break. */
4868 reinit_frame_cache ();
4870 breakpoint_retire_moribund ();
4872 /* First, distinguish signals caused by the debugger from signals
4873 that have to do with the program's own actions. Note that
4874 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
4875 on the operating system version. Here we detect when a SIGILL or
4876 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
4877 something similar for SIGSEGV, since a SIGSEGV will be generated
4878 when we're trying to execute a breakpoint instruction on a
4879 non-executable stack. This happens for call dummy breakpoints
4880 for architectures like SPARC that place call dummies on the
4882 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
4883 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
4884 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
4885 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
4887 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
4889 if (breakpoint_inserted_here_p (regcache
->aspace (),
4890 regcache_read_pc (regcache
)))
4893 fprintf_unfiltered (gdb_stdlog
,
4894 "infrun: Treating signal as SIGTRAP\n");
4895 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
4899 /* Mark the non-executing threads accordingly. In all-stop, all
4900 threads of all processes are stopped when we get any event
4901 reported. In non-stop mode, only the event thread stops. */
4905 if (!target_is_non_stop_p ())
4906 mark_ptid
= minus_one_ptid
;
4907 else if (ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
4908 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4910 /* If we're handling a process exit in non-stop mode, even
4911 though threads haven't been deleted yet, one would think
4912 that there is nothing to do, as threads of the dead process
4913 will be soon deleted, and threads of any other process were
4914 left running. However, on some targets, threads survive a
4915 process exit event. E.g., for the "checkpoint" command,
4916 when the current checkpoint/fork exits, linux-fork.c
4917 automatically switches to another fork from within
4918 target_mourn_inferior, by associating the same
4919 inferior/thread to another fork. We haven't mourned yet at
4920 this point, but we must mark any threads left in the
4921 process as not-executing so that finish_thread_state marks
4922 them stopped (in the user's perspective) if/when we present
4923 the stop to the user. */
4924 mark_ptid
= pid_to_ptid (ptid_get_pid (ecs
->ptid
));
4927 mark_ptid
= ecs
->ptid
;
4929 set_executing (mark_ptid
, 0);
4931 /* Likewise the resumed flag. */
4932 set_resumed (mark_ptid
, 0);
4935 switch (ecs
->ws
.kind
)
4937 case TARGET_WAITKIND_LOADED
:
4939 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
4940 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
4941 context_switch (ecs
->ptid
);
4942 /* Ignore gracefully during startup of the inferior, as it might
4943 be the shell which has just loaded some objects, otherwise
4944 add the symbols for the newly loaded objects. Also ignore at
4945 the beginning of an attach or remote session; we will query
4946 the full list of libraries once the connection is
4949 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
4950 if (stop_soon
== NO_STOP_QUIETLY
)
4952 struct regcache
*regcache
;
4954 regcache
= get_thread_regcache (ecs
->ptid
);
4956 handle_solib_event ();
4958 ecs
->event_thread
->control
.stop_bpstat
4959 = bpstat_stop_status (regcache
->aspace (),
4960 stop_pc
, ecs
->ptid
, &ecs
->ws
);
4962 if (handle_stop_requested (ecs
))
4965 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4967 /* A catchpoint triggered. */
4968 process_event_stop_test (ecs
);
4972 /* If requested, stop when the dynamic linker notifies
4973 gdb of events. This allows the user to get control
4974 and place breakpoints in initializer routines for
4975 dynamically loaded objects (among other things). */
4976 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4977 if (stop_on_solib_events
)
4979 /* Make sure we print "Stopped due to solib-event" in
4981 stop_print_frame
= 1;
4988 /* If we are skipping through a shell, or through shared library
4989 loading that we aren't interested in, resume the program. If
4990 we're running the program normally, also resume. */
4991 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
4993 /* Loading of shared libraries might have changed breakpoint
4994 addresses. Make sure new breakpoints are inserted. */
4995 if (stop_soon
== NO_STOP_QUIETLY
)
4996 insert_breakpoints ();
4997 resume (GDB_SIGNAL_0
);
4998 prepare_to_wait (ecs
);
5002 /* But stop if we're attaching or setting up a remote
5004 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5005 || stop_soon
== STOP_QUIETLY_REMOTE
)
5008 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5013 internal_error (__FILE__
, __LINE__
,
5014 _("unhandled stop_soon: %d"), (int) stop_soon
);
5016 case TARGET_WAITKIND_SPURIOUS
:
5018 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
5019 if (handle_stop_requested (ecs
))
5021 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5022 context_switch (ecs
->ptid
);
5023 resume (GDB_SIGNAL_0
);
5024 prepare_to_wait (ecs
);
5027 case TARGET_WAITKIND_THREAD_CREATED
:
5029 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_THREAD_CREATED\n");
5030 if (handle_stop_requested (ecs
))
5032 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5033 context_switch (ecs
->ptid
);
5034 if (!switch_back_to_stepped_thread (ecs
))
5038 case TARGET_WAITKIND_EXITED
:
5039 case TARGET_WAITKIND_SIGNALLED
:
5042 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5043 fprintf_unfiltered (gdb_stdlog
,
5044 "infrun: TARGET_WAITKIND_EXITED\n");
5046 fprintf_unfiltered (gdb_stdlog
,
5047 "infrun: TARGET_WAITKIND_SIGNALLED\n");
5050 inferior_ptid
= ecs
->ptid
;
5051 set_current_inferior (find_inferior_ptid (ecs
->ptid
));
5052 set_current_program_space (current_inferior ()->pspace
);
5053 handle_vfork_child_exec_or_exit (0);
5054 target_terminal::ours (); /* Must do this before mourn anyway. */
5056 /* Clearing any previous state of convenience variables. */
5057 clear_exit_convenience_vars ();
5059 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5061 /* Record the exit code in the convenience variable $_exitcode, so
5062 that the user can inspect this again later. */
5063 set_internalvar_integer (lookup_internalvar ("_exitcode"),
5064 (LONGEST
) ecs
->ws
.value
.integer
);
5066 /* Also record this in the inferior itself. */
5067 current_inferior ()->has_exit_code
= 1;
5068 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
5070 /* Support the --return-child-result option. */
5071 return_child_result_value
= ecs
->ws
.value
.integer
;
5073 gdb::observers::exited
.notify (ecs
->ws
.value
.integer
);
5077 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5078 struct gdbarch
*gdbarch
= regcache
->arch ();
5080 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
5082 /* Set the value of the internal variable $_exitsignal,
5083 which holds the signal uncaught by the inferior. */
5084 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
5085 gdbarch_gdb_signal_to_target (gdbarch
,
5086 ecs
->ws
.value
.sig
));
5090 /* We don't have access to the target's method used for
5091 converting between signal numbers (GDB's internal
5092 representation <-> target's representation).
5093 Therefore, we cannot do a good job at displaying this
5094 information to the user. It's better to just warn
5095 her about it (if infrun debugging is enabled), and
5098 fprintf_filtered (gdb_stdlog
, _("\
5099 Cannot fill $_exitsignal with the correct signal number.\n"));
5102 gdb::observers::signal_exited
.notify (ecs
->ws
.value
.sig
);
5105 gdb_flush (gdb_stdout
);
5106 target_mourn_inferior (inferior_ptid
);
5107 stop_print_frame
= 0;
5111 /* The following are the only cases in which we keep going;
5112 the above cases end in a continue or goto. */
5113 case TARGET_WAITKIND_FORKED
:
5114 case TARGET_WAITKIND_VFORKED
:
5117 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
5118 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
5120 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
5123 /* Check whether the inferior is displaced stepping. */
5125 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5126 struct gdbarch
*gdbarch
= regcache
->arch ();
5128 /* If checking displaced stepping is supported, and thread
5129 ecs->ptid is displaced stepping. */
5130 if (displaced_step_in_progress_thread (ecs
->ptid
))
5132 struct inferior
*parent_inf
5133 = find_inferior_ptid (ecs
->ptid
);
5134 struct regcache
*child_regcache
;
5135 CORE_ADDR parent_pc
;
5137 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
5138 indicating that the displaced stepping of syscall instruction
5139 has been done. Perform cleanup for parent process here. Note
5140 that this operation also cleans up the child process for vfork,
5141 because their pages are shared. */
5142 displaced_step_fixup (ecs
->ptid
, GDB_SIGNAL_TRAP
);
5143 /* Start a new step-over in another thread if there's one
5147 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
5149 struct displaced_step_inferior_state
*displaced
5150 = get_displaced_stepping_state (ptid_get_pid (ecs
->ptid
));
5152 /* Restore scratch pad for child process. */
5153 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
5156 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
5157 the child's PC is also within the scratchpad. Set the child's PC
5158 to the parent's PC value, which has already been fixed up.
5159 FIXME: we use the parent's aspace here, although we're touching
5160 the child, because the child hasn't been added to the inferior
5161 list yet at this point. */
5164 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
5166 parent_inf
->aspace
);
5167 /* Read PC value of parent process. */
5168 parent_pc
= regcache_read_pc (regcache
);
5170 if (debug_displaced
)
5171 fprintf_unfiltered (gdb_stdlog
,
5172 "displaced: write child pc from %s to %s\n",
5174 regcache_read_pc (child_regcache
)),
5175 paddress (gdbarch
, parent_pc
));
5177 regcache_write_pc (child_regcache
, parent_pc
);
5181 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5182 context_switch (ecs
->ptid
);
5184 /* Immediately detach breakpoints from the child before there's
5185 any chance of letting the user delete breakpoints from the
5186 breakpoint lists. If we don't do this early, it's easy to
5187 leave left over traps in the child, vis: "break foo; catch
5188 fork; c; <fork>; del; c; <child calls foo>". We only follow
5189 the fork on the last `continue', and by that time the
5190 breakpoint at "foo" is long gone from the breakpoint table.
5191 If we vforked, then we don't need to unpatch here, since both
5192 parent and child are sharing the same memory pages; we'll
5193 need to unpatch at follow/detach time instead to be certain
5194 that new breakpoints added between catchpoint hit time and
5195 vfork follow are detached. */
5196 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
5198 /* This won't actually modify the breakpoint list, but will
5199 physically remove the breakpoints from the child. */
5200 detach_breakpoints (ecs
->ws
.value
.related_pid
);
5203 delete_just_stopped_threads_single_step_breakpoints ();
5205 /* In case the event is caught by a catchpoint, remember that
5206 the event is to be followed at the next resume of the thread,
5207 and not immediately. */
5208 ecs
->event_thread
->pending_follow
= ecs
->ws
;
5210 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5212 ecs
->event_thread
->control
.stop_bpstat
5213 = bpstat_stop_status (get_current_regcache ()->aspace (),
5214 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5216 if (handle_stop_requested (ecs
))
5219 /* If no catchpoint triggered for this, then keep going. Note
5220 that we're interested in knowing the bpstat actually causes a
5221 stop, not just if it may explain the signal. Software
5222 watchpoints, for example, always appear in the bpstat. */
5223 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5229 = (follow_fork_mode_string
== follow_fork_mode_child
);
5231 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5233 should_resume
= follow_fork ();
5236 child
= ecs
->ws
.value
.related_pid
;
5238 /* At this point, the parent is marked running, and the
5239 child is marked stopped. */
5241 /* If not resuming the parent, mark it stopped. */
5242 if (follow_child
&& !detach_fork
&& !non_stop
&& !sched_multi
)
5243 set_running (parent
, 0);
5245 /* If resuming the child, mark it running. */
5246 if (follow_child
|| (!detach_fork
&& (non_stop
|| sched_multi
)))
5247 set_running (child
, 1);
5249 /* In non-stop mode, also resume the other branch. */
5250 if (!detach_fork
&& (non_stop
5251 || (sched_multi
&& target_is_non_stop_p ())))
5254 switch_to_thread (parent
);
5256 switch_to_thread (child
);
5258 ecs
->event_thread
= inferior_thread ();
5259 ecs
->ptid
= inferior_ptid
;
5264 switch_to_thread (child
);
5266 switch_to_thread (parent
);
5268 ecs
->event_thread
= inferior_thread ();
5269 ecs
->ptid
= inferior_ptid
;
5277 process_event_stop_test (ecs
);
5280 case TARGET_WAITKIND_VFORK_DONE
:
5281 /* Done with the shared memory region. Re-insert breakpoints in
5282 the parent, and keep going. */
5285 fprintf_unfiltered (gdb_stdlog
,
5286 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
5288 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5289 context_switch (ecs
->ptid
);
5291 current_inferior ()->waiting_for_vfork_done
= 0;
5292 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
5294 if (handle_stop_requested (ecs
))
5297 /* This also takes care of reinserting breakpoints in the
5298 previously locked inferior. */
5302 case TARGET_WAITKIND_EXECD
:
5304 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
5306 /* Note we can't read registers yet (the stop_pc), because we
5307 don't yet know the inferior's post-exec architecture.
5308 'stop_pc' is explicitly read below instead. */
5309 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5310 switch_to_thread_no_regs (ecs
->event_thread
);
5312 /* Do whatever is necessary to the parent branch of the vfork. */
5313 handle_vfork_child_exec_or_exit (1);
5315 /* This causes the eventpoints and symbol table to be reset.
5316 Must do this now, before trying to determine whether to
5318 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
5320 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5322 /* In follow_exec we may have deleted the original thread and
5323 created a new one. Make sure that the event thread is the
5324 execd thread for that case (this is a nop otherwise). */
5325 ecs
->event_thread
= inferior_thread ();
5327 ecs
->event_thread
->control
.stop_bpstat
5328 = bpstat_stop_status (get_current_regcache ()->aspace (),
5329 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5331 /* Note that this may be referenced from inside
5332 bpstat_stop_status above, through inferior_has_execd. */
5333 xfree (ecs
->ws
.value
.execd_pathname
);
5334 ecs
->ws
.value
.execd_pathname
= NULL
;
5336 if (handle_stop_requested (ecs
))
5339 /* If no catchpoint triggered for this, then keep going. */
5340 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5342 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5346 process_event_stop_test (ecs
);
5349 /* Be careful not to try to gather much state about a thread
5350 that's in a syscall. It's frequently a losing proposition. */
5351 case TARGET_WAITKIND_SYSCALL_ENTRY
:
5353 fprintf_unfiltered (gdb_stdlog
,
5354 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
5355 /* Getting the current syscall number. */
5356 if (handle_syscall_event (ecs
) == 0)
5357 process_event_stop_test (ecs
);
5360 /* Before examining the threads further, step this thread to
5361 get it entirely out of the syscall. (We get notice of the
5362 event when the thread is just on the verge of exiting a
5363 syscall. Stepping one instruction seems to get it back
5365 case TARGET_WAITKIND_SYSCALL_RETURN
:
5367 fprintf_unfiltered (gdb_stdlog
,
5368 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
5369 if (handle_syscall_event (ecs
) == 0)
5370 process_event_stop_test (ecs
);
5373 case TARGET_WAITKIND_STOPPED
:
5375 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
5376 handle_signal_stop (ecs
);
5379 case TARGET_WAITKIND_NO_HISTORY
:
5381 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
5382 /* Reverse execution: target ran out of history info. */
5384 /* Switch to the stopped thread. */
5385 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5386 context_switch (ecs
->ptid
);
5388 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
5390 delete_just_stopped_threads_single_step_breakpoints ();
5391 stop_pc
= regcache_read_pc (get_thread_regcache (inferior_ptid
));
5393 if (handle_stop_requested (ecs
))
5396 gdb::observers::no_history
.notify ();
5402 /* A wrapper around handle_inferior_event_1, which also makes sure
5403 that all temporary struct value objects that were created during
5404 the handling of the event get deleted at the end. */
5407 handle_inferior_event (struct execution_control_state
*ecs
)
5409 struct value
*mark
= value_mark ();
5411 handle_inferior_event_1 (ecs
);
5412 /* Purge all temporary values created during the event handling,
5413 as it could be a long time before we return to the command level
5414 where such values would otherwise be purged. */
5415 value_free_to_mark (mark
);
5418 /* Restart threads back to what they were trying to do back when we
5419 paused them for an in-line step-over. The EVENT_THREAD thread is
5423 restart_threads (struct thread_info
*event_thread
)
5425 struct thread_info
*tp
;
5427 /* In case the instruction just stepped spawned a new thread. */
5428 update_thread_list ();
5430 ALL_NON_EXITED_THREADS (tp
)
5432 if (tp
== event_thread
)
5435 fprintf_unfiltered (gdb_stdlog
,
5436 "infrun: restart threads: "
5437 "[%s] is event thread\n",
5438 target_pid_to_str (tp
->ptid
));
5442 if (!(tp
->state
== THREAD_RUNNING
|| tp
->control
.in_infcall
))
5445 fprintf_unfiltered (gdb_stdlog
,
5446 "infrun: restart threads: "
5447 "[%s] not meant to be running\n",
5448 target_pid_to_str (tp
->ptid
));
5455 fprintf_unfiltered (gdb_stdlog
,
5456 "infrun: restart threads: [%s] resumed\n",
5457 target_pid_to_str (tp
->ptid
));
5458 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
5462 if (thread_is_in_step_over_chain (tp
))
5465 fprintf_unfiltered (gdb_stdlog
,
5466 "infrun: restart threads: "
5467 "[%s] needs step-over\n",
5468 target_pid_to_str (tp
->ptid
));
5469 gdb_assert (!tp
->resumed
);
5474 if (tp
->suspend
.waitstatus_pending_p
)
5477 fprintf_unfiltered (gdb_stdlog
,
5478 "infrun: restart threads: "
5479 "[%s] has pending status\n",
5480 target_pid_to_str (tp
->ptid
));
5485 gdb_assert (!tp
->stop_requested
);
5487 /* If some thread needs to start a step-over at this point, it
5488 should still be in the step-over queue, and thus skipped
5490 if (thread_still_needs_step_over (tp
))
5492 internal_error (__FILE__
, __LINE__
,
5493 "thread [%s] needs a step-over, but not in "
5494 "step-over queue\n",
5495 target_pid_to_str (tp
->ptid
));
5498 if (currently_stepping (tp
))
5501 fprintf_unfiltered (gdb_stdlog
,
5502 "infrun: restart threads: [%s] was stepping\n",
5503 target_pid_to_str (tp
->ptid
));
5504 keep_going_stepped_thread (tp
);
5508 struct execution_control_state ecss
;
5509 struct execution_control_state
*ecs
= &ecss
;
5512 fprintf_unfiltered (gdb_stdlog
,
5513 "infrun: restart threads: [%s] continuing\n",
5514 target_pid_to_str (tp
->ptid
));
5515 reset_ecs (ecs
, tp
);
5516 switch_to_thread (tp
->ptid
);
5517 keep_going_pass_signal (ecs
);
5522 /* Callback for iterate_over_threads. Find a resumed thread that has
5523 a pending waitstatus. */
5526 resumed_thread_with_pending_status (struct thread_info
*tp
,
5530 && tp
->suspend
.waitstatus_pending_p
);
5533 /* Called when we get an event that may finish an in-line or
5534 out-of-line (displaced stepping) step-over started previously.
5535 Return true if the event is processed and we should go back to the
5536 event loop; false if the caller should continue processing the
5540 finish_step_over (struct execution_control_state
*ecs
)
5542 int had_step_over_info
;
5544 displaced_step_fixup (ecs
->ptid
,
5545 ecs
->event_thread
->suspend
.stop_signal
);
5547 had_step_over_info
= step_over_info_valid_p ();
5549 if (had_step_over_info
)
5551 /* If we're stepping over a breakpoint with all threads locked,
5552 then only the thread that was stepped should be reporting
5554 gdb_assert (ecs
->event_thread
->control
.trap_expected
);
5556 clear_step_over_info ();
5559 if (!target_is_non_stop_p ())
5562 /* Start a new step-over in another thread if there's one that
5566 /* If we were stepping over a breakpoint before, and haven't started
5567 a new in-line step-over sequence, then restart all other threads
5568 (except the event thread). We can't do this in all-stop, as then
5569 e.g., we wouldn't be able to issue any other remote packet until
5570 these other threads stop. */
5571 if (had_step_over_info
&& !step_over_info_valid_p ())
5573 struct thread_info
*pending
;
5575 /* If we only have threads with pending statuses, the restart
5576 below won't restart any thread and so nothing re-inserts the
5577 breakpoint we just stepped over. But we need it inserted
5578 when we later process the pending events, otherwise if
5579 another thread has a pending event for this breakpoint too,
5580 we'd discard its event (because the breakpoint that
5581 originally caused the event was no longer inserted). */
5582 context_switch (ecs
->ptid
);
5583 insert_breakpoints ();
5585 restart_threads (ecs
->event_thread
);
5587 /* If we have events pending, go through handle_inferior_event
5588 again, picking up a pending event at random. This avoids
5589 thread starvation. */
5591 /* But not if we just stepped over a watchpoint in order to let
5592 the instruction execute so we can evaluate its expression.
5593 The set of watchpoints that triggered is recorded in the
5594 breakpoint objects themselves (see bp->watchpoint_triggered).
5595 If we processed another event first, that other event could
5596 clobber this info. */
5597 if (ecs
->event_thread
->stepping_over_watchpoint
)
5600 pending
= iterate_over_threads (resumed_thread_with_pending_status
,
5602 if (pending
!= NULL
)
5604 struct thread_info
*tp
= ecs
->event_thread
;
5605 struct regcache
*regcache
;
5609 fprintf_unfiltered (gdb_stdlog
,
5610 "infrun: found resumed threads with "
5611 "pending events, saving status\n");
5614 gdb_assert (pending
!= tp
);
5616 /* Record the event thread's event for later. */
5617 save_waitstatus (tp
, &ecs
->ws
);
5618 /* This was cleared early, by handle_inferior_event. Set it
5619 so this pending event is considered by
5623 gdb_assert (!tp
->executing
);
5625 regcache
= get_thread_regcache (tp
->ptid
);
5626 tp
->suspend
.stop_pc
= regcache_read_pc (regcache
);
5630 fprintf_unfiltered (gdb_stdlog
,
5631 "infrun: saved stop_pc=%s for %s "
5632 "(currently_stepping=%d)\n",
5633 paddress (target_gdbarch (),
5634 tp
->suspend
.stop_pc
),
5635 target_pid_to_str (tp
->ptid
),
5636 currently_stepping (tp
));
5639 /* This in-line step-over finished; clear this so we won't
5640 start a new one. This is what handle_signal_stop would
5641 do, if we returned false. */
5642 tp
->stepping_over_breakpoint
= 0;
5644 /* Wake up the event loop again. */
5645 mark_async_event_handler (infrun_async_inferior_event_token
);
5647 prepare_to_wait (ecs
);
5655 /* Come here when the program has stopped with a signal. */
5658 handle_signal_stop (struct execution_control_state
*ecs
)
5660 struct frame_info
*frame
;
5661 struct gdbarch
*gdbarch
;
5662 int stopped_by_watchpoint
;
5663 enum stop_kind stop_soon
;
5666 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
5668 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
5670 /* Do we need to clean up the state of a thread that has
5671 completed a displaced single-step? (Doing so usually affects
5672 the PC, so do it here, before we set stop_pc.) */
5673 if (finish_step_over (ecs
))
5676 /* If we either finished a single-step or hit a breakpoint, but
5677 the user wanted this thread to be stopped, pretend we got a
5678 SIG0 (generic unsignaled stop). */
5679 if (ecs
->event_thread
->stop_requested
5680 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5681 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5683 stop_pc
= regcache_read_pc (get_thread_regcache (ecs
->ptid
));
5687 struct regcache
*regcache
= get_thread_regcache (ecs
->ptid
);
5688 struct gdbarch
*gdbarch
= regcache
->arch ();
5689 scoped_restore save_inferior_ptid
= make_scoped_restore (&inferior_ptid
);
5691 inferior_ptid
= ecs
->ptid
;
5693 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
5694 paddress (gdbarch
, stop_pc
));
5695 if (target_stopped_by_watchpoint ())
5699 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
5701 if (target_stopped_data_address (¤t_target
, &addr
))
5702 fprintf_unfiltered (gdb_stdlog
,
5703 "infrun: stopped data address = %s\n",
5704 paddress (gdbarch
, addr
));
5706 fprintf_unfiltered (gdb_stdlog
,
5707 "infrun: (no data address available)\n");
5711 /* This is originated from start_remote(), start_inferior() and
5712 shared libraries hook functions. */
5713 stop_soon
= get_inferior_stop_soon (ecs
->ptid
);
5714 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
5716 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5717 context_switch (ecs
->ptid
);
5719 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5720 stop_print_frame
= 1;
5725 /* This originates from attach_command(). We need to overwrite
5726 the stop_signal here, because some kernels don't ignore a
5727 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5728 See more comments in inferior.h. On the other hand, if we
5729 get a non-SIGSTOP, report it to the user - assume the backend
5730 will handle the SIGSTOP if it should show up later.
5732 Also consider that the attach is complete when we see a
5733 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5734 target extended-remote report it instead of a SIGSTOP
5735 (e.g. gdbserver). We already rely on SIGTRAP being our
5736 signal, so this is no exception.
5738 Also consider that the attach is complete when we see a
5739 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5740 the target to stop all threads of the inferior, in case the
5741 low level attach operation doesn't stop them implicitly. If
5742 they weren't stopped implicitly, then the stub will report a
5743 GDB_SIGNAL_0, meaning: stopped for no particular reason
5744 other than GDB's request. */
5745 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5746 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
5747 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5748 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
5750 stop_print_frame
= 1;
5752 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5756 /* See if something interesting happened to the non-current thread. If
5757 so, then switch to that thread. */
5758 if (!ptid_equal (ecs
->ptid
, inferior_ptid
))
5761 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
5763 context_switch (ecs
->ptid
);
5765 if (deprecated_context_hook
)
5766 deprecated_context_hook (ptid_to_global_thread_id (ecs
->ptid
));
5769 /* At this point, get hold of the now-current thread's frame. */
5770 frame
= get_current_frame ();
5771 gdbarch
= get_frame_arch (frame
);
5773 /* Pull the single step breakpoints out of the target. */
5774 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5776 struct regcache
*regcache
;
5779 regcache
= get_thread_regcache (ecs
->ptid
);
5780 const address_space
*aspace
= regcache
->aspace ();
5782 pc
= regcache_read_pc (regcache
);
5784 /* However, before doing so, if this single-step breakpoint was
5785 actually for another thread, set this thread up for moving
5787 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
5790 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
5794 fprintf_unfiltered (gdb_stdlog
,
5795 "infrun: [%s] hit another thread's "
5796 "single-step breakpoint\n",
5797 target_pid_to_str (ecs
->ptid
));
5799 ecs
->hit_singlestep_breakpoint
= 1;
5806 fprintf_unfiltered (gdb_stdlog
,
5807 "infrun: [%s] hit its "
5808 "single-step breakpoint\n",
5809 target_pid_to_str (ecs
->ptid
));
5813 delete_just_stopped_threads_single_step_breakpoints ();
5815 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5816 && ecs
->event_thread
->control
.trap_expected
5817 && ecs
->event_thread
->stepping_over_watchpoint
)
5818 stopped_by_watchpoint
= 0;
5820 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
5822 /* If necessary, step over this watchpoint. We'll be back to display
5824 if (stopped_by_watchpoint
5825 && (target_have_steppable_watchpoint
5826 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
5828 /* At this point, we are stopped at an instruction which has
5829 attempted to write to a piece of memory under control of
5830 a watchpoint. The instruction hasn't actually executed
5831 yet. If we were to evaluate the watchpoint expression
5832 now, we would get the old value, and therefore no change
5833 would seem to have occurred.
5835 In order to make watchpoints work `right', we really need
5836 to complete the memory write, and then evaluate the
5837 watchpoint expression. We do this by single-stepping the
5840 It may not be necessary to disable the watchpoint to step over
5841 it. For example, the PA can (with some kernel cooperation)
5842 single step over a watchpoint without disabling the watchpoint.
5844 It is far more common to need to disable a watchpoint to step
5845 the inferior over it. If we have non-steppable watchpoints,
5846 we must disable the current watchpoint; it's simplest to
5847 disable all watchpoints.
5849 Any breakpoint at PC must also be stepped over -- if there's
5850 one, it will have already triggered before the watchpoint
5851 triggered, and we either already reported it to the user, or
5852 it didn't cause a stop and we called keep_going. In either
5853 case, if there was a breakpoint at PC, we must be trying to
5855 ecs
->event_thread
->stepping_over_watchpoint
= 1;
5860 ecs
->event_thread
->stepping_over_breakpoint
= 0;
5861 ecs
->event_thread
->stepping_over_watchpoint
= 0;
5862 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
5863 ecs
->event_thread
->control
.stop_step
= 0;
5864 stop_print_frame
= 1;
5865 stopped_by_random_signal
= 0;
5867 /* Hide inlined functions starting here, unless we just performed stepi or
5868 nexti. After stepi and nexti, always show the innermost frame (not any
5869 inline function call sites). */
5870 if (ecs
->event_thread
->control
.step_range_end
!= 1)
5872 const address_space
*aspace
=
5873 get_thread_regcache (ecs
->ptid
)->aspace ();
5875 /* skip_inline_frames is expensive, so we avoid it if we can
5876 determine that the address is one where functions cannot have
5877 been inlined. This improves performance with inferiors that
5878 load a lot of shared libraries, because the solib event
5879 breakpoint is defined as the address of a function (i.e. not
5880 inline). Note that we have to check the previous PC as well
5881 as the current one to catch cases when we have just
5882 single-stepped off a breakpoint prior to reinstating it.
5883 Note that we're assuming that the code we single-step to is
5884 not inline, but that's not definitive: there's nothing
5885 preventing the event breakpoint function from containing
5886 inlined code, and the single-step ending up there. If the
5887 user had set a breakpoint on that inlined code, the missing
5888 skip_inline_frames call would break things. Fortunately
5889 that's an extremely unlikely scenario. */
5890 if (!pc_at_non_inline_function (aspace
, stop_pc
, &ecs
->ws
)
5891 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5892 && ecs
->event_thread
->control
.trap_expected
5893 && pc_at_non_inline_function (aspace
,
5894 ecs
->event_thread
->prev_pc
,
5897 skip_inline_frames (ecs
->ptid
);
5899 /* Re-fetch current thread's frame in case that invalidated
5901 frame
= get_current_frame ();
5902 gdbarch
= get_frame_arch (frame
);
5906 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5907 && ecs
->event_thread
->control
.trap_expected
5908 && gdbarch_single_step_through_delay_p (gdbarch
)
5909 && currently_stepping (ecs
->event_thread
))
5911 /* We're trying to step off a breakpoint. Turns out that we're
5912 also on an instruction that needs to be stepped multiple
5913 times before it's been fully executing. E.g., architectures
5914 with a delay slot. It needs to be stepped twice, once for
5915 the instruction and once for the delay slot. */
5916 int step_through_delay
5917 = gdbarch_single_step_through_delay (gdbarch
, frame
);
5919 if (debug_infrun
&& step_through_delay
)
5920 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
5921 if (ecs
->event_thread
->control
.step_range_end
== 0
5922 && step_through_delay
)
5924 /* The user issued a continue when stopped at a breakpoint.
5925 Set up for another trap and get out of here. */
5926 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5930 else if (step_through_delay
)
5932 /* The user issued a step when stopped at a breakpoint.
5933 Maybe we should stop, maybe we should not - the delay
5934 slot *might* correspond to a line of source. In any
5935 case, don't decide that here, just set
5936 ecs->stepping_over_breakpoint, making sure we
5937 single-step again before breakpoints are re-inserted. */
5938 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5942 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
5943 handles this event. */
5944 ecs
->event_thread
->control
.stop_bpstat
5945 = bpstat_stop_status (get_current_regcache ()->aspace (),
5946 stop_pc
, ecs
->ptid
, &ecs
->ws
);
5948 /* Following in case break condition called a
5950 stop_print_frame
= 1;
5952 /* This is where we handle "moribund" watchpoints. Unlike
5953 software breakpoints traps, hardware watchpoint traps are
5954 always distinguishable from random traps. If no high-level
5955 watchpoint is associated with the reported stop data address
5956 anymore, then the bpstat does not explain the signal ---
5957 simply make sure to ignore it if `stopped_by_watchpoint' is
5961 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5962 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5964 && stopped_by_watchpoint
)
5965 fprintf_unfiltered (gdb_stdlog
,
5966 "infrun: no user watchpoint explains "
5967 "watchpoint SIGTRAP, ignoring\n");
5969 /* NOTE: cagney/2003-03-29: These checks for a random signal
5970 at one stage in the past included checks for an inferior
5971 function call's call dummy's return breakpoint. The original
5972 comment, that went with the test, read:
5974 ``End of a stack dummy. Some systems (e.g. Sony news) give
5975 another signal besides SIGTRAP, so check here as well as
5978 If someone ever tries to get call dummys on a
5979 non-executable stack to work (where the target would stop
5980 with something like a SIGSEGV), then those tests might need
5981 to be re-instated. Given, however, that the tests were only
5982 enabled when momentary breakpoints were not being used, I
5983 suspect that it won't be the case.
5985 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
5986 be necessary for call dummies on a non-executable stack on
5989 /* See if the breakpoints module can explain the signal. */
5991 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5992 ecs
->event_thread
->suspend
.stop_signal
);
5994 /* Maybe this was a trap for a software breakpoint that has since
5996 if (random_signal
&& target_stopped_by_sw_breakpoint ())
5998 if (program_breakpoint_here_p (gdbarch
, stop_pc
))
6000 struct regcache
*regcache
;
6003 /* Re-adjust PC to what the program would see if GDB was not
6005 regcache
= get_thread_regcache (ecs
->event_thread
->ptid
);
6006 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
6009 gdb::optional
<scoped_restore_tmpl
<int>>
6010 restore_operation_disable
;
6012 if (record_full_is_used ())
6013 restore_operation_disable
.emplace
6014 (record_full_gdb_operation_disable_set ());
6016 regcache_write_pc (regcache
, stop_pc
+ decr_pc
);
6021 /* A delayed software breakpoint event. Ignore the trap. */
6023 fprintf_unfiltered (gdb_stdlog
,
6024 "infrun: delayed software breakpoint "
6025 "trap, ignoring\n");
6030 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
6031 has since been removed. */
6032 if (random_signal
&& target_stopped_by_hw_breakpoint ())
6034 /* A delayed hardware breakpoint event. Ignore the trap. */
6036 fprintf_unfiltered (gdb_stdlog
,
6037 "infrun: delayed hardware breakpoint/watchpoint "
6038 "trap, ignoring\n");
6042 /* If not, perhaps stepping/nexting can. */
6044 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6045 && currently_stepping (ecs
->event_thread
));
6047 /* Perhaps the thread hit a single-step breakpoint of _another_
6048 thread. Single-step breakpoints are transparent to the
6049 breakpoints module. */
6051 random_signal
= !ecs
->hit_singlestep_breakpoint
;
6053 /* No? Perhaps we got a moribund watchpoint. */
6055 random_signal
= !stopped_by_watchpoint
;
6057 /* Always stop if the user explicitly requested this thread to
6059 if (ecs
->event_thread
->stop_requested
)
6063 fprintf_unfiltered (gdb_stdlog
, "infrun: user-requested stop\n");
6066 /* For the program's own signals, act according to
6067 the signal handling tables. */
6071 /* Signal not for debugging purposes. */
6072 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
6073 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
6076 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
6077 gdb_signal_to_symbol_string (stop_signal
));
6079 stopped_by_random_signal
= 1;
6081 /* Always stop on signals if we're either just gaining control
6082 of the program, or the user explicitly requested this thread
6083 to remain stopped. */
6084 if (stop_soon
!= NO_STOP_QUIETLY
6085 || ecs
->event_thread
->stop_requested
6087 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
6093 /* Notify observers the signal has "handle print" set. Note we
6094 returned early above if stopping; normal_stop handles the
6095 printing in that case. */
6096 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
6098 /* The signal table tells us to print about this signal. */
6099 target_terminal::ours_for_output ();
6100 gdb::observers::signal_received
.notify (ecs
->event_thread
->suspend
.stop_signal
);
6101 target_terminal::inferior ();
6104 /* Clear the signal if it should not be passed. */
6105 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
6106 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6108 if (ecs
->event_thread
->prev_pc
== stop_pc
6109 && ecs
->event_thread
->control
.trap_expected
6110 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6112 /* We were just starting a new sequence, attempting to
6113 single-step off of a breakpoint and expecting a SIGTRAP.
6114 Instead this signal arrives. This signal will take us out
6115 of the stepping range so GDB needs to remember to, when
6116 the signal handler returns, resume stepping off that
6118 /* To simplify things, "continue" is forced to use the same
6119 code paths as single-step - set a breakpoint at the
6120 signal return address and then, once hit, step off that
6123 fprintf_unfiltered (gdb_stdlog
,
6124 "infrun: signal arrived while stepping over "
6127 insert_hp_step_resume_breakpoint_at_frame (frame
);
6128 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6129 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6130 ecs
->event_thread
->control
.trap_expected
= 0;
6132 /* If we were nexting/stepping some other thread, switch to
6133 it, so that we don't continue it, losing control. */
6134 if (!switch_back_to_stepped_thread (ecs
))
6139 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
6140 && (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
6141 || ecs
->event_thread
->control
.step_range_end
== 1)
6142 && frame_id_eq (get_stack_frame_id (frame
),
6143 ecs
->event_thread
->control
.step_stack_frame_id
)
6144 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6146 /* The inferior is about to take a signal that will take it
6147 out of the single step range. Set a breakpoint at the
6148 current PC (which is presumably where the signal handler
6149 will eventually return) and then allow the inferior to
6152 Note that this is only needed for a signal delivered
6153 while in the single-step range. Nested signals aren't a
6154 problem as they eventually all return. */
6156 fprintf_unfiltered (gdb_stdlog
,
6157 "infrun: signal may take us out of "
6158 "single-step range\n");
6160 clear_step_over_info ();
6161 insert_hp_step_resume_breakpoint_at_frame (frame
);
6162 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6163 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6164 ecs
->event_thread
->control
.trap_expected
= 0;
6169 /* Note: step_resume_breakpoint may be non-NULL. This occures
6170 when either there's a nested signal, or when there's a
6171 pending signal enabled just as the signal handler returns
6172 (leaving the inferior at the step-resume-breakpoint without
6173 actually executing it). Either way continue until the
6174 breakpoint is really hit. */
6176 if (!switch_back_to_stepped_thread (ecs
))
6179 fprintf_unfiltered (gdb_stdlog
,
6180 "infrun: random signal, keep going\n");
6187 process_event_stop_test (ecs
);
6190 /* Come here when we've got some debug event / signal we can explain
6191 (IOW, not a random signal), and test whether it should cause a
6192 stop, or whether we should resume the inferior (transparently).
6193 E.g., could be a breakpoint whose condition evaluates false; we
6194 could be still stepping within the line; etc. */
6197 process_event_stop_test (struct execution_control_state
*ecs
)
6199 struct symtab_and_line stop_pc_sal
;
6200 struct frame_info
*frame
;
6201 struct gdbarch
*gdbarch
;
6202 CORE_ADDR jmp_buf_pc
;
6203 struct bpstat_what what
;
6205 /* Handle cases caused by hitting a breakpoint. */
6207 frame
= get_current_frame ();
6208 gdbarch
= get_frame_arch (frame
);
6210 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
6212 if (what
.call_dummy
)
6214 stop_stack_dummy
= what
.call_dummy
;
6217 /* A few breakpoint types have callbacks associated (e.g.,
6218 bp_jit_event). Run them now. */
6219 bpstat_run_callbacks (ecs
->event_thread
->control
.stop_bpstat
);
6221 /* If we hit an internal event that triggers symbol changes, the
6222 current frame will be invalidated within bpstat_what (e.g., if we
6223 hit an internal solib event). Re-fetch it. */
6224 frame
= get_current_frame ();
6225 gdbarch
= get_frame_arch (frame
);
6227 switch (what
.main_action
)
6229 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
6230 /* If we hit the breakpoint at longjmp while stepping, we
6231 install a momentary breakpoint at the target of the
6235 fprintf_unfiltered (gdb_stdlog
,
6236 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
6238 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6240 if (what
.is_longjmp
)
6242 struct value
*arg_value
;
6244 /* If we set the longjmp breakpoint via a SystemTap probe,
6245 then use it to extract the arguments. The destination PC
6246 is the third argument to the probe. */
6247 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
6250 jmp_buf_pc
= value_as_address (arg_value
);
6251 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
6253 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
6254 || !gdbarch_get_longjmp_target (gdbarch
,
6255 frame
, &jmp_buf_pc
))
6258 fprintf_unfiltered (gdb_stdlog
,
6259 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
6260 "(!gdbarch_get_longjmp_target)\n");
6265 /* Insert a breakpoint at resume address. */
6266 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
6269 check_exception_resume (ecs
, frame
);
6273 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
6275 struct frame_info
*init_frame
;
6277 /* There are several cases to consider.
6279 1. The initiating frame no longer exists. In this case we
6280 must stop, because the exception or longjmp has gone too
6283 2. The initiating frame exists, and is the same as the
6284 current frame. We stop, because the exception or longjmp
6287 3. The initiating frame exists and is different from the
6288 current frame. This means the exception or longjmp has
6289 been caught beneath the initiating frame, so keep going.
6291 4. longjmp breakpoint has been placed just to protect
6292 against stale dummy frames and user is not interested in
6293 stopping around longjmps. */
6296 fprintf_unfiltered (gdb_stdlog
,
6297 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
6299 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
6301 delete_exception_resume_breakpoint (ecs
->event_thread
);
6303 if (what
.is_longjmp
)
6305 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
6307 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
6315 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
6319 struct frame_id current_id
6320 = get_frame_id (get_current_frame ());
6321 if (frame_id_eq (current_id
,
6322 ecs
->event_thread
->initiating_frame
))
6324 /* Case 2. Fall through. */
6334 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6336 delete_step_resume_breakpoint (ecs
->event_thread
);
6338 end_stepping_range (ecs
);
6342 case BPSTAT_WHAT_SINGLE
:
6344 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
6345 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6346 /* Still need to check other stuff, at least the case where we
6347 are stepping and step out of the right range. */
6350 case BPSTAT_WHAT_STEP_RESUME
:
6352 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
6354 delete_step_resume_breakpoint (ecs
->event_thread
);
6355 if (ecs
->event_thread
->control
.proceed_to_finish
6356 && execution_direction
== EXEC_REVERSE
)
6358 struct thread_info
*tp
= ecs
->event_thread
;
6360 /* We are finishing a function in reverse, and just hit the
6361 step-resume breakpoint at the start address of the
6362 function, and we're almost there -- just need to back up
6363 by one more single-step, which should take us back to the
6365 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
6369 fill_in_stop_func (gdbarch
, ecs
);
6370 if (stop_pc
== ecs
->stop_func_start
6371 && execution_direction
== EXEC_REVERSE
)
6373 /* We are stepping over a function call in reverse, and just
6374 hit the step-resume breakpoint at the start address of
6375 the function. Go back to single-stepping, which should
6376 take us back to the function call. */
6377 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6383 case BPSTAT_WHAT_STOP_NOISY
:
6385 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
6386 stop_print_frame
= 1;
6388 /* Assume the thread stopped for a breapoint. We'll still check
6389 whether a/the breakpoint is there when the thread is next
6391 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6396 case BPSTAT_WHAT_STOP_SILENT
:
6398 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
6399 stop_print_frame
= 0;
6401 /* Assume the thread stopped for a breapoint. We'll still check
6402 whether a/the breakpoint is there when the thread is next
6404 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6408 case BPSTAT_WHAT_HP_STEP_RESUME
:
6410 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
6412 delete_step_resume_breakpoint (ecs
->event_thread
);
6413 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
6415 /* Back when the step-resume breakpoint was inserted, we
6416 were trying to single-step off a breakpoint. Go back to
6418 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6419 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6425 case BPSTAT_WHAT_KEEP_CHECKING
:
6429 /* If we stepped a permanent breakpoint and we had a high priority
6430 step-resume breakpoint for the address we stepped, but we didn't
6431 hit it, then we must have stepped into the signal handler. The
6432 step-resume was only necessary to catch the case of _not_
6433 stepping into the handler, so delete it, and fall through to
6434 checking whether the step finished. */
6435 if (ecs
->event_thread
->stepped_breakpoint
)
6437 struct breakpoint
*sr_bp
6438 = ecs
->event_thread
->control
.step_resume_breakpoint
;
6441 && sr_bp
->loc
->permanent
6442 && sr_bp
->type
== bp_hp_step_resume
6443 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
6446 fprintf_unfiltered (gdb_stdlog
,
6447 "infrun: stepped permanent breakpoint, stopped in "
6449 delete_step_resume_breakpoint (ecs
->event_thread
);
6450 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6454 /* We come here if we hit a breakpoint but should not stop for it.
6455 Possibly we also were stepping and should stop for that. So fall
6456 through and test for stepping. But, if not stepping, do not
6459 /* In all-stop mode, if we're currently stepping but have stopped in
6460 some other thread, we need to switch back to the stepped thread. */
6461 if (switch_back_to_stepped_thread (ecs
))
6464 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
6467 fprintf_unfiltered (gdb_stdlog
,
6468 "infrun: step-resume breakpoint is inserted\n");
6470 /* Having a step-resume breakpoint overrides anything
6471 else having to do with stepping commands until
6472 that breakpoint is reached. */
6477 if (ecs
->event_thread
->control
.step_range_end
== 0)
6480 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
6481 /* Likewise if we aren't even stepping. */
6486 /* Re-fetch current thread's frame in case the code above caused
6487 the frame cache to be re-initialized, making our FRAME variable
6488 a dangling pointer. */
6489 frame
= get_current_frame ();
6490 gdbarch
= get_frame_arch (frame
);
6491 fill_in_stop_func (gdbarch
, ecs
);
6493 /* If stepping through a line, keep going if still within it.
6495 Note that step_range_end is the address of the first instruction
6496 beyond the step range, and NOT the address of the last instruction
6499 Note also that during reverse execution, we may be stepping
6500 through a function epilogue and therefore must detect when
6501 the current-frame changes in the middle of a line. */
6503 if (pc_in_thread_step_range (stop_pc
, ecs
->event_thread
)
6504 && (execution_direction
!= EXEC_REVERSE
6505 || frame_id_eq (get_frame_id (frame
),
6506 ecs
->event_thread
->control
.step_frame_id
)))
6510 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
6511 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
6512 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
6514 /* Tentatively re-enable range stepping; `resume' disables it if
6515 necessary (e.g., if we're stepping over a breakpoint or we
6516 have software watchpoints). */
6517 ecs
->event_thread
->control
.may_range_step
= 1;
6519 /* When stepping backward, stop at beginning of line range
6520 (unless it's the function entry point, in which case
6521 keep going back to the call point). */
6522 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
6523 && stop_pc
!= ecs
->stop_func_start
6524 && execution_direction
== EXEC_REVERSE
)
6525 end_stepping_range (ecs
);
6532 /* We stepped out of the stepping range. */
6534 /* If we are stepping at the source level and entered the runtime
6535 loader dynamic symbol resolution code...
6537 EXEC_FORWARD: we keep on single stepping until we exit the run
6538 time loader code and reach the callee's address.
6540 EXEC_REVERSE: we've already executed the callee (backward), and
6541 the runtime loader code is handled just like any other
6542 undebuggable function call. Now we need only keep stepping
6543 backward through the trampoline code, and that's handled further
6544 down, so there is nothing for us to do here. */
6546 if (execution_direction
!= EXEC_REVERSE
6547 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6548 && in_solib_dynsym_resolve_code (stop_pc
))
6550 CORE_ADDR pc_after_resolver
=
6551 gdbarch_skip_solib_resolver (gdbarch
, stop_pc
);
6554 fprintf_unfiltered (gdb_stdlog
,
6555 "infrun: stepped into dynsym resolve code\n");
6557 if (pc_after_resolver
)
6559 /* Set up a step-resume breakpoint at the address
6560 indicated by SKIP_SOLIB_RESOLVER. */
6561 symtab_and_line sr_sal
;
6562 sr_sal
.pc
= pc_after_resolver
;
6563 sr_sal
.pspace
= get_frame_program_space (frame
);
6565 insert_step_resume_breakpoint_at_sal (gdbarch
,
6566 sr_sal
, null_frame_id
);
6573 if (ecs
->event_thread
->control
.step_range_end
!= 1
6574 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6575 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6576 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
6579 fprintf_unfiltered (gdb_stdlog
,
6580 "infrun: stepped into signal trampoline\n");
6581 /* The inferior, while doing a "step" or "next", has ended up in
6582 a signal trampoline (either by a signal being delivered or by
6583 the signal handler returning). Just single-step until the
6584 inferior leaves the trampoline (either by calling the handler
6590 /* If we're in the return path from a shared library trampoline,
6591 we want to proceed through the trampoline when stepping. */
6592 /* macro/2012-04-25: This needs to come before the subroutine
6593 call check below as on some targets return trampolines look
6594 like subroutine calls (MIPS16 return thunks). */
6595 if (gdbarch_in_solib_return_trampoline (gdbarch
,
6596 stop_pc
, ecs
->stop_func_name
)
6597 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6599 /* Determine where this trampoline returns. */
6600 CORE_ADDR real_stop_pc
;
6602 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6605 fprintf_unfiltered (gdb_stdlog
,
6606 "infrun: stepped into solib return tramp\n");
6608 /* Only proceed through if we know where it's going. */
6611 /* And put the step-breakpoint there and go until there. */
6612 symtab_and_line sr_sal
;
6613 sr_sal
.pc
= real_stop_pc
;
6614 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6615 sr_sal
.pspace
= get_frame_program_space (frame
);
6617 /* Do not specify what the fp should be when we stop since
6618 on some machines the prologue is where the new fp value
6620 insert_step_resume_breakpoint_at_sal (gdbarch
,
6621 sr_sal
, null_frame_id
);
6623 /* Restart without fiddling with the step ranges or
6630 /* Check for subroutine calls. The check for the current frame
6631 equalling the step ID is not necessary - the check of the
6632 previous frame's ID is sufficient - but it is a common case and
6633 cheaper than checking the previous frame's ID.
6635 NOTE: frame_id_eq will never report two invalid frame IDs as
6636 being equal, so to get into this block, both the current and
6637 previous frame must have valid frame IDs. */
6638 /* The outer_frame_id check is a heuristic to detect stepping
6639 through startup code. If we step over an instruction which
6640 sets the stack pointer from an invalid value to a valid value,
6641 we may detect that as a subroutine call from the mythical
6642 "outermost" function. This could be fixed by marking
6643 outermost frames as !stack_p,code_p,special_p. Then the
6644 initial outermost frame, before sp was valid, would
6645 have code_addr == &_start. See the comment in frame_id_eq
6647 if (!frame_id_eq (get_stack_frame_id (frame
),
6648 ecs
->event_thread
->control
.step_stack_frame_id
)
6649 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6650 ecs
->event_thread
->control
.step_stack_frame_id
)
6651 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
6653 || (ecs
->event_thread
->control
.step_start_function
6654 != find_pc_function (stop_pc
)))))
6656 CORE_ADDR real_stop_pc
;
6659 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
6661 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
6663 /* I presume that step_over_calls is only 0 when we're
6664 supposed to be stepping at the assembly language level
6665 ("stepi"). Just stop. */
6666 /* And this works the same backward as frontward. MVS */
6667 end_stepping_range (ecs
);
6671 /* Reverse stepping through solib trampolines. */
6673 if (execution_direction
== EXEC_REVERSE
6674 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6675 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6676 || (ecs
->stop_func_start
== 0
6677 && in_solib_dynsym_resolve_code (stop_pc
))))
6679 /* Any solib trampoline code can be handled in reverse
6680 by simply continuing to single-step. We have already
6681 executed the solib function (backwards), and a few
6682 steps will take us back through the trampoline to the
6688 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6690 /* We're doing a "next".
6692 Normal (forward) execution: set a breakpoint at the
6693 callee's return address (the address at which the caller
6696 Reverse (backward) execution. set the step-resume
6697 breakpoint at the start of the function that we just
6698 stepped into (backwards), and continue to there. When we
6699 get there, we'll need to single-step back to the caller. */
6701 if (execution_direction
== EXEC_REVERSE
)
6703 /* If we're already at the start of the function, we've either
6704 just stepped backward into a single instruction function,
6705 or stepped back out of a signal handler to the first instruction
6706 of the function. Just keep going, which will single-step back
6708 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
6710 /* Normal function call return (static or dynamic). */
6711 symtab_and_line sr_sal
;
6712 sr_sal
.pc
= ecs
->stop_func_start
;
6713 sr_sal
.pspace
= get_frame_program_space (frame
);
6714 insert_step_resume_breakpoint_at_sal (gdbarch
,
6715 sr_sal
, null_frame_id
);
6719 insert_step_resume_breakpoint_at_caller (frame
);
6725 /* If we are in a function call trampoline (a stub between the
6726 calling routine and the real function), locate the real
6727 function. That's what tells us (a) whether we want to step
6728 into it at all, and (b) what prologue we want to run to the
6729 end of, if we do step into it. */
6730 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
6731 if (real_stop_pc
== 0)
6732 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6733 if (real_stop_pc
!= 0)
6734 ecs
->stop_func_start
= real_stop_pc
;
6736 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
6738 symtab_and_line sr_sal
;
6739 sr_sal
.pc
= ecs
->stop_func_start
;
6740 sr_sal
.pspace
= get_frame_program_space (frame
);
6742 insert_step_resume_breakpoint_at_sal (gdbarch
,
6743 sr_sal
, null_frame_id
);
6748 /* If we have line number information for the function we are
6749 thinking of stepping into and the function isn't on the skip
6752 If there are several symtabs at that PC (e.g. with include
6753 files), just want to know whether *any* of them have line
6754 numbers. find_pc_line handles this. */
6756 struct symtab_and_line tmp_sal
;
6758 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
6759 if (tmp_sal
.line
!= 0
6760 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
6763 if (execution_direction
== EXEC_REVERSE
)
6764 handle_step_into_function_backward (gdbarch
, ecs
);
6766 handle_step_into_function (gdbarch
, ecs
);
6771 /* If we have no line number and the step-stop-if-no-debug is
6772 set, we stop the step so that the user has a chance to switch
6773 in assembly mode. */
6774 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6775 && step_stop_if_no_debug
)
6777 end_stepping_range (ecs
);
6781 if (execution_direction
== EXEC_REVERSE
)
6783 /* If we're already at the start of the function, we've either just
6784 stepped backward into a single instruction function without line
6785 number info, or stepped back out of a signal handler to the first
6786 instruction of the function without line number info. Just keep
6787 going, which will single-step back to the caller. */
6788 if (ecs
->stop_func_start
!= stop_pc
)
6790 /* Set a breakpoint at callee's start address.
6791 From there we can step once and be back in the caller. */
6792 symtab_and_line sr_sal
;
6793 sr_sal
.pc
= ecs
->stop_func_start
;
6794 sr_sal
.pspace
= get_frame_program_space (frame
);
6795 insert_step_resume_breakpoint_at_sal (gdbarch
,
6796 sr_sal
, null_frame_id
);
6800 /* Set a breakpoint at callee's return address (the address
6801 at which the caller will resume). */
6802 insert_step_resume_breakpoint_at_caller (frame
);
6808 /* Reverse stepping through solib trampolines. */
6810 if (execution_direction
== EXEC_REVERSE
6811 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6813 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6814 || (ecs
->stop_func_start
== 0
6815 && in_solib_dynsym_resolve_code (stop_pc
)))
6817 /* Any solib trampoline code can be handled in reverse
6818 by simply continuing to single-step. We have already
6819 executed the solib function (backwards), and a few
6820 steps will take us back through the trampoline to the
6825 else if (in_solib_dynsym_resolve_code (stop_pc
))
6827 /* Stepped backward into the solib dynsym resolver.
6828 Set a breakpoint at its start and continue, then
6829 one more step will take us out. */
6830 symtab_and_line sr_sal
;
6831 sr_sal
.pc
= ecs
->stop_func_start
;
6832 sr_sal
.pspace
= get_frame_program_space (frame
);
6833 insert_step_resume_breakpoint_at_sal (gdbarch
,
6834 sr_sal
, null_frame_id
);
6840 stop_pc_sal
= find_pc_line (stop_pc
, 0);
6842 /* NOTE: tausq/2004-05-24: This if block used to be done before all
6843 the trampoline processing logic, however, there are some trampolines
6844 that have no names, so we should do trampoline handling first. */
6845 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6846 && ecs
->stop_func_name
== NULL
6847 && stop_pc_sal
.line
== 0)
6850 fprintf_unfiltered (gdb_stdlog
,
6851 "infrun: stepped into undebuggable function\n");
6853 /* The inferior just stepped into, or returned to, an
6854 undebuggable function (where there is no debugging information
6855 and no line number corresponding to the address where the
6856 inferior stopped). Since we want to skip this kind of code,
6857 we keep going until the inferior returns from this
6858 function - unless the user has asked us not to (via
6859 set step-mode) or we no longer know how to get back
6860 to the call site. */
6861 if (step_stop_if_no_debug
6862 || !frame_id_p (frame_unwind_caller_id (frame
)))
6864 /* If we have no line number and the step-stop-if-no-debug
6865 is set, we stop the step so that the user has a chance to
6866 switch in assembly mode. */
6867 end_stepping_range (ecs
);
6872 /* Set a breakpoint at callee's return address (the address
6873 at which the caller will resume). */
6874 insert_step_resume_breakpoint_at_caller (frame
);
6880 if (ecs
->event_thread
->control
.step_range_end
== 1)
6882 /* It is stepi or nexti. We always want to stop stepping after
6885 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
6886 end_stepping_range (ecs
);
6890 if (stop_pc_sal
.line
== 0)
6892 /* We have no line number information. That means to stop
6893 stepping (does this always happen right after one instruction,
6894 when we do "s" in a function with no line numbers,
6895 or can this happen as a result of a return or longjmp?). */
6897 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
6898 end_stepping_range (ecs
);
6902 /* Look for "calls" to inlined functions, part one. If the inline
6903 frame machinery detected some skipped call sites, we have entered
6904 a new inline function. */
6906 if (frame_id_eq (get_frame_id (get_current_frame ()),
6907 ecs
->event_thread
->control
.step_frame_id
)
6908 && inline_skipped_frames (ecs
->ptid
))
6911 fprintf_unfiltered (gdb_stdlog
,
6912 "infrun: stepped into inlined function\n");
6914 symtab_and_line call_sal
= find_frame_sal (get_current_frame ());
6916 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
6918 /* For "step", we're going to stop. But if the call site
6919 for this inlined function is on the same source line as
6920 we were previously stepping, go down into the function
6921 first. Otherwise stop at the call site. */
6923 if (call_sal
.line
== ecs
->event_thread
->current_line
6924 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6925 step_into_inline_frame (ecs
->ptid
);
6927 end_stepping_range (ecs
);
6932 /* For "next", we should stop at the call site if it is on a
6933 different source line. Otherwise continue through the
6934 inlined function. */
6935 if (call_sal
.line
== ecs
->event_thread
->current_line
6936 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6939 end_stepping_range (ecs
);
6944 /* Look for "calls" to inlined functions, part two. If we are still
6945 in the same real function we were stepping through, but we have
6946 to go further up to find the exact frame ID, we are stepping
6947 through a more inlined call beyond its call site. */
6949 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
6950 && !frame_id_eq (get_frame_id (get_current_frame ()),
6951 ecs
->event_thread
->control
.step_frame_id
)
6952 && stepped_in_from (get_current_frame (),
6953 ecs
->event_thread
->control
.step_frame_id
))
6956 fprintf_unfiltered (gdb_stdlog
,
6957 "infrun: stepping through inlined function\n");
6959 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6962 end_stepping_range (ecs
);
6966 if ((stop_pc
== stop_pc_sal
.pc
)
6967 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
6968 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
6970 /* We are at the start of a different line. So stop. Note that
6971 we don't stop if we step into the middle of a different line.
6972 That is said to make things like for (;;) statements work
6975 fprintf_unfiltered (gdb_stdlog
,
6976 "infrun: stepped to a different line\n");
6977 end_stepping_range (ecs
);
6981 /* We aren't done stepping.
6983 Optimize by setting the stepping range to the line.
6984 (We might not be in the original line, but if we entered a
6985 new line in mid-statement, we continue stepping. This makes
6986 things like for(;;) statements work better.) */
6988 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
6989 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
6990 ecs
->event_thread
->control
.may_range_step
= 1;
6991 set_step_info (frame
, stop_pc_sal
);
6994 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
6998 /* In all-stop mode, if we're currently stepping but have stopped in
6999 some other thread, we may need to switch back to the stepped
7000 thread. Returns true we set the inferior running, false if we left
7001 it stopped (and the event needs further processing). */
7004 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
7006 if (!target_is_non_stop_p ())
7008 struct thread_info
*tp
;
7009 struct thread_info
*stepping_thread
;
7011 /* If any thread is blocked on some internal breakpoint, and we
7012 simply need to step over that breakpoint to get it going
7013 again, do that first. */
7015 /* However, if we see an event for the stepping thread, then we
7016 know all other threads have been moved past their breakpoints
7017 already. Let the caller check whether the step is finished,
7018 etc., before deciding to move it past a breakpoint. */
7019 if (ecs
->event_thread
->control
.step_range_end
!= 0)
7022 /* Check if the current thread is blocked on an incomplete
7023 step-over, interrupted by a random signal. */
7024 if (ecs
->event_thread
->control
.trap_expected
7025 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
7029 fprintf_unfiltered (gdb_stdlog
,
7030 "infrun: need to finish step-over of [%s]\n",
7031 target_pid_to_str (ecs
->event_thread
->ptid
));
7037 /* Check if the current thread is blocked by a single-step
7038 breakpoint of another thread. */
7039 if (ecs
->hit_singlestep_breakpoint
)
7043 fprintf_unfiltered (gdb_stdlog
,
7044 "infrun: need to step [%s] over single-step "
7046 target_pid_to_str (ecs
->ptid
));
7052 /* If this thread needs yet another step-over (e.g., stepping
7053 through a delay slot), do it first before moving on to
7055 if (thread_still_needs_step_over (ecs
->event_thread
))
7059 fprintf_unfiltered (gdb_stdlog
,
7060 "infrun: thread [%s] still needs step-over\n",
7061 target_pid_to_str (ecs
->event_thread
->ptid
));
7067 /* If scheduler locking applies even if not stepping, there's no
7068 need to walk over threads. Above we've checked whether the
7069 current thread is stepping. If some other thread not the
7070 event thread is stepping, then it must be that scheduler
7071 locking is not in effect. */
7072 if (schedlock_applies (ecs
->event_thread
))
7075 /* Otherwise, we no longer expect a trap in the current thread.
7076 Clear the trap_expected flag before switching back -- this is
7077 what keep_going does as well, if we call it. */
7078 ecs
->event_thread
->control
.trap_expected
= 0;
7080 /* Likewise, clear the signal if it should not be passed. */
7081 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7082 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7084 /* Do all pending step-overs before actually proceeding with
7086 if (start_step_over ())
7088 prepare_to_wait (ecs
);
7092 /* Look for the stepping/nexting thread. */
7093 stepping_thread
= NULL
;
7095 ALL_NON_EXITED_THREADS (tp
)
7097 /* Ignore threads of processes the caller is not
7100 && ptid_get_pid (tp
->ptid
) != ptid_get_pid (ecs
->ptid
))
7103 /* When stepping over a breakpoint, we lock all threads
7104 except the one that needs to move past the breakpoint.
7105 If a non-event thread has this set, the "incomplete
7106 step-over" check above should have caught it earlier. */
7107 if (tp
->control
.trap_expected
)
7109 internal_error (__FILE__
, __LINE__
,
7110 "[%s] has inconsistent state: "
7111 "trap_expected=%d\n",
7112 target_pid_to_str (tp
->ptid
),
7113 tp
->control
.trap_expected
);
7116 /* Did we find the stepping thread? */
7117 if (tp
->control
.step_range_end
)
7119 /* Yep. There should only one though. */
7120 gdb_assert (stepping_thread
== NULL
);
7122 /* The event thread is handled at the top, before we
7124 gdb_assert (tp
!= ecs
->event_thread
);
7126 /* If some thread other than the event thread is
7127 stepping, then scheduler locking can't be in effect,
7128 otherwise we wouldn't have resumed the current event
7129 thread in the first place. */
7130 gdb_assert (!schedlock_applies (tp
));
7132 stepping_thread
= tp
;
7136 if (stepping_thread
!= NULL
)
7139 fprintf_unfiltered (gdb_stdlog
,
7140 "infrun: switching back to stepped thread\n");
7142 if (keep_going_stepped_thread (stepping_thread
))
7144 prepare_to_wait (ecs
);
7153 /* Set a previously stepped thread back to stepping. Returns true on
7154 success, false if the resume is not possible (e.g., the thread
7158 keep_going_stepped_thread (struct thread_info
*tp
)
7160 struct frame_info
*frame
;
7161 struct execution_control_state ecss
;
7162 struct execution_control_state
*ecs
= &ecss
;
7164 /* If the stepping thread exited, then don't try to switch back and
7165 resume it, which could fail in several different ways depending
7166 on the target. Instead, just keep going.
7168 We can find a stepping dead thread in the thread list in two
7171 - The target supports thread exit events, and when the target
7172 tries to delete the thread from the thread list, inferior_ptid
7173 pointed at the exiting thread. In such case, calling
7174 delete_thread does not really remove the thread from the list;
7175 instead, the thread is left listed, with 'exited' state.
7177 - The target's debug interface does not support thread exit
7178 events, and so we have no idea whatsoever if the previously
7179 stepping thread is still alive. For that reason, we need to
7180 synchronously query the target now. */
7182 if (is_exited (tp
->ptid
)
7183 || !target_thread_alive (tp
->ptid
))
7186 fprintf_unfiltered (gdb_stdlog
,
7187 "infrun: not resuming previously "
7188 "stepped thread, it has vanished\n");
7190 delete_thread (tp
->ptid
);
7195 fprintf_unfiltered (gdb_stdlog
,
7196 "infrun: resuming previously stepped thread\n");
7198 reset_ecs (ecs
, tp
);
7199 switch_to_thread (tp
->ptid
);
7201 stop_pc
= regcache_read_pc (get_thread_regcache (tp
->ptid
));
7202 frame
= get_current_frame ();
7204 /* If the PC of the thread we were trying to single-step has
7205 changed, then that thread has trapped or been signaled, but the
7206 event has not been reported to GDB yet. Re-poll the target
7207 looking for this particular thread's event (i.e. temporarily
7208 enable schedlock) by:
7210 - setting a break at the current PC
7211 - resuming that particular thread, only (by setting trap
7214 This prevents us continuously moving the single-step breakpoint
7215 forward, one instruction at a time, overstepping. */
7217 if (stop_pc
!= tp
->prev_pc
)
7222 fprintf_unfiltered (gdb_stdlog
,
7223 "infrun: expected thread advanced also (%s -> %s)\n",
7224 paddress (target_gdbarch (), tp
->prev_pc
),
7225 paddress (target_gdbarch (), stop_pc
));
7227 /* Clear the info of the previous step-over, as it's no longer
7228 valid (if the thread was trying to step over a breakpoint, it
7229 has already succeeded). It's what keep_going would do too,
7230 if we called it. Do this before trying to insert the sss
7231 breakpoint, otherwise if we were previously trying to step
7232 over this exact address in another thread, the breakpoint is
7234 clear_step_over_info ();
7235 tp
->control
.trap_expected
= 0;
7237 insert_single_step_breakpoint (get_frame_arch (frame
),
7238 get_frame_address_space (frame
),
7242 resume_ptid
= internal_resume_ptid (tp
->control
.stepping_command
);
7243 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
7248 fprintf_unfiltered (gdb_stdlog
,
7249 "infrun: expected thread still hasn't advanced\n");
7251 keep_going_pass_signal (ecs
);
7256 /* Is thread TP in the middle of (software or hardware)
7257 single-stepping? (Note the result of this function must never be
7258 passed directly as target_resume's STEP parameter.) */
7261 currently_stepping (struct thread_info
*tp
)
7263 return ((tp
->control
.step_range_end
7264 && tp
->control
.step_resume_breakpoint
== NULL
)
7265 || tp
->control
.trap_expected
7266 || tp
->stepped_breakpoint
7267 || bpstat_should_step ());
7270 /* Inferior has stepped into a subroutine call with source code that
7271 we should not step over. Do step to the first line of code in
7275 handle_step_into_function (struct gdbarch
*gdbarch
,
7276 struct execution_control_state
*ecs
)
7278 fill_in_stop_func (gdbarch
, ecs
);
7280 compunit_symtab
*cust
= find_pc_compunit_symtab (stop_pc
);
7281 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7282 ecs
->stop_func_start
7283 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7285 symtab_and_line stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7286 /* Use the step_resume_break to step until the end of the prologue,
7287 even if that involves jumps (as it seems to on the vax under
7289 /* If the prologue ends in the middle of a source line, continue to
7290 the end of that source line (if it is still within the function).
7291 Otherwise, just go to end of prologue. */
7292 if (stop_func_sal
.end
7293 && stop_func_sal
.pc
!= ecs
->stop_func_start
7294 && stop_func_sal
.end
< ecs
->stop_func_end
)
7295 ecs
->stop_func_start
= stop_func_sal
.end
;
7297 /* Architectures which require breakpoint adjustment might not be able
7298 to place a breakpoint at the computed address. If so, the test
7299 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7300 ecs->stop_func_start to an address at which a breakpoint may be
7301 legitimately placed.
7303 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7304 made, GDB will enter an infinite loop when stepping through
7305 optimized code consisting of VLIW instructions which contain
7306 subinstructions corresponding to different source lines. On
7307 FR-V, it's not permitted to place a breakpoint on any but the
7308 first subinstruction of a VLIW instruction. When a breakpoint is
7309 set, GDB will adjust the breakpoint address to the beginning of
7310 the VLIW instruction. Thus, we need to make the corresponding
7311 adjustment here when computing the stop address. */
7313 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
7315 ecs
->stop_func_start
7316 = gdbarch_adjust_breakpoint_address (gdbarch
,
7317 ecs
->stop_func_start
);
7320 if (ecs
->stop_func_start
== stop_pc
)
7322 /* We are already there: stop now. */
7323 end_stepping_range (ecs
);
7328 /* Put the step-breakpoint there and go until there. */
7329 symtab_and_line sr_sal
;
7330 sr_sal
.pc
= ecs
->stop_func_start
;
7331 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
7332 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
7334 /* Do not specify what the fp should be when we stop since on
7335 some machines the prologue is where the new fp value is
7337 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
7339 /* And make sure stepping stops right away then. */
7340 ecs
->event_thread
->control
.step_range_end
7341 = ecs
->event_thread
->control
.step_range_start
;
7346 /* Inferior has stepped backward into a subroutine call with source
7347 code that we should not step over. Do step to the beginning of the
7348 last line of code in it. */
7351 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
7352 struct execution_control_state
*ecs
)
7354 struct compunit_symtab
*cust
;
7355 struct symtab_and_line stop_func_sal
;
7357 fill_in_stop_func (gdbarch
, ecs
);
7359 cust
= find_pc_compunit_symtab (stop_pc
);
7360 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7361 ecs
->stop_func_start
7362 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7364 stop_func_sal
= find_pc_line (stop_pc
, 0);
7366 /* OK, we're just going to keep stepping here. */
7367 if (stop_func_sal
.pc
== stop_pc
)
7369 /* We're there already. Just stop stepping now. */
7370 end_stepping_range (ecs
);
7374 /* Else just reset the step range and keep going.
7375 No step-resume breakpoint, they don't work for
7376 epilogues, which can have multiple entry paths. */
7377 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
7378 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
7384 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7385 This is used to both functions and to skip over code. */
7388 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
7389 struct symtab_and_line sr_sal
,
7390 struct frame_id sr_id
,
7391 enum bptype sr_type
)
7393 /* There should never be more than one step-resume or longjmp-resume
7394 breakpoint per thread, so we should never be setting a new
7395 step_resume_breakpoint when one is already active. */
7396 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
7397 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
7400 fprintf_unfiltered (gdb_stdlog
,
7401 "infrun: inserting step-resume breakpoint at %s\n",
7402 paddress (gdbarch
, sr_sal
.pc
));
7404 inferior_thread ()->control
.step_resume_breakpoint
7405 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
).release ();
7409 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
7410 struct symtab_and_line sr_sal
,
7411 struct frame_id sr_id
)
7413 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
7418 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7419 This is used to skip a potential signal handler.
7421 This is called with the interrupted function's frame. The signal
7422 handler, when it returns, will resume the interrupted function at
7426 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
7428 gdb_assert (return_frame
!= NULL
);
7430 struct gdbarch
*gdbarch
= get_frame_arch (return_frame
);
7432 symtab_and_line sr_sal
;
7433 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
7434 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7435 sr_sal
.pspace
= get_frame_program_space (return_frame
);
7437 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
7438 get_stack_frame_id (return_frame
),
7442 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7443 is used to skip a function after stepping into it (for "next" or if
7444 the called function has no debugging information).
7446 The current function has almost always been reached by single
7447 stepping a call or return instruction. NEXT_FRAME belongs to the
7448 current function, and the breakpoint will be set at the caller's
7451 This is a separate function rather than reusing
7452 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7453 get_prev_frame, which may stop prematurely (see the implementation
7454 of frame_unwind_caller_id for an example). */
7457 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
7459 /* We shouldn't have gotten here if we don't know where the call site
7461 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
7463 struct gdbarch
*gdbarch
= frame_unwind_caller_arch (next_frame
);
7465 symtab_and_line sr_sal
;
7466 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
7467 frame_unwind_caller_pc (next_frame
));
7468 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7469 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
7471 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
7472 frame_unwind_caller_id (next_frame
));
7475 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7476 new breakpoint at the target of a jmp_buf. The handling of
7477 longjmp-resume uses the same mechanisms used for handling
7478 "step-resume" breakpoints. */
7481 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
7483 /* There should never be more than one longjmp-resume breakpoint per
7484 thread, so we should never be setting a new
7485 longjmp_resume_breakpoint when one is already active. */
7486 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
7489 fprintf_unfiltered (gdb_stdlog
,
7490 "infrun: inserting longjmp-resume breakpoint at %s\n",
7491 paddress (gdbarch
, pc
));
7493 inferior_thread ()->control
.exception_resume_breakpoint
=
7494 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
).release ();
7497 /* Insert an exception resume breakpoint. TP is the thread throwing
7498 the exception. The block B is the block of the unwinder debug hook
7499 function. FRAME is the frame corresponding to the call to this
7500 function. SYM is the symbol of the function argument holding the
7501 target PC of the exception. */
7504 insert_exception_resume_breakpoint (struct thread_info
*tp
,
7505 const struct block
*b
,
7506 struct frame_info
*frame
,
7511 struct block_symbol vsym
;
7512 struct value
*value
;
7514 struct breakpoint
*bp
;
7516 vsym
= lookup_symbol_search_name (SYMBOL_SEARCH_NAME (sym
),
7518 value
= read_var_value (vsym
.symbol
, vsym
.block
, frame
);
7519 /* If the value was optimized out, revert to the old behavior. */
7520 if (! value_optimized_out (value
))
7522 handler
= value_as_address (value
);
7525 fprintf_unfiltered (gdb_stdlog
,
7526 "infrun: exception resume at %lx\n",
7527 (unsigned long) handler
);
7529 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7531 bp_exception_resume
).release ();
7533 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7536 bp
->thread
= tp
->global_num
;
7537 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7540 CATCH (e
, RETURN_MASK_ERROR
)
7542 /* We want to ignore errors here. */
7547 /* A helper for check_exception_resume that sets an
7548 exception-breakpoint based on a SystemTap probe. */
7551 insert_exception_resume_from_probe (struct thread_info
*tp
,
7552 const struct bound_probe
*probe
,
7553 struct frame_info
*frame
)
7555 struct value
*arg_value
;
7557 struct breakpoint
*bp
;
7559 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
7563 handler
= value_as_address (arg_value
);
7566 fprintf_unfiltered (gdb_stdlog
,
7567 "infrun: exception resume at %s\n",
7568 paddress (get_objfile_arch (probe
->objfile
),
7571 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7572 handler
, bp_exception_resume
).release ();
7573 bp
->thread
= tp
->global_num
;
7574 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7577 /* This is called when an exception has been intercepted. Check to
7578 see whether the exception's destination is of interest, and if so,
7579 set an exception resume breakpoint there. */
7582 check_exception_resume (struct execution_control_state
*ecs
,
7583 struct frame_info
*frame
)
7585 struct bound_probe probe
;
7586 struct symbol
*func
;
7588 /* First see if this exception unwinding breakpoint was set via a
7589 SystemTap probe point. If so, the probe has two arguments: the
7590 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7591 set a breakpoint there. */
7592 probe
= find_probe_by_pc (get_frame_pc (frame
));
7595 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
7599 func
= get_frame_function (frame
);
7605 const struct block
*b
;
7606 struct block_iterator iter
;
7610 /* The exception breakpoint is a thread-specific breakpoint on
7611 the unwinder's debug hook, declared as:
7613 void _Unwind_DebugHook (void *cfa, void *handler);
7615 The CFA argument indicates the frame to which control is
7616 about to be transferred. HANDLER is the destination PC.
7618 We ignore the CFA and set a temporary breakpoint at HANDLER.
7619 This is not extremely efficient but it avoids issues in gdb
7620 with computing the DWARF CFA, and it also works even in weird
7621 cases such as throwing an exception from inside a signal
7624 b
= SYMBOL_BLOCK_VALUE (func
);
7625 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
7627 if (!SYMBOL_IS_ARGUMENT (sym
))
7634 insert_exception_resume_breakpoint (ecs
->event_thread
,
7640 CATCH (e
, RETURN_MASK_ERROR
)
7647 stop_waiting (struct execution_control_state
*ecs
)
7650 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
7652 /* Let callers know we don't want to wait for the inferior anymore. */
7653 ecs
->wait_some_more
= 0;
7655 /* If all-stop, but the target is always in non-stop mode, stop all
7656 threads now that we're presenting the stop to the user. */
7657 if (!non_stop
&& target_is_non_stop_p ())
7658 stop_all_threads ();
7661 /* Like keep_going, but passes the signal to the inferior, even if the
7662 signal is set to nopass. */
7665 keep_going_pass_signal (struct execution_control_state
*ecs
)
7667 gdb_assert (ptid_equal (ecs
->event_thread
->ptid
, inferior_ptid
));
7668 gdb_assert (!ecs
->event_thread
->resumed
);
7670 /* Save the pc before execution, to compare with pc after stop. */
7671 ecs
->event_thread
->prev_pc
7672 = regcache_read_pc (get_thread_regcache (ecs
->ptid
));
7674 if (ecs
->event_thread
->control
.trap_expected
)
7676 struct thread_info
*tp
= ecs
->event_thread
;
7679 fprintf_unfiltered (gdb_stdlog
,
7680 "infrun: %s has trap_expected set, "
7681 "resuming to collect trap\n",
7682 target_pid_to_str (tp
->ptid
));
7684 /* We haven't yet gotten our trap, and either: intercepted a
7685 non-signal event (e.g., a fork); or took a signal which we
7686 are supposed to pass through to the inferior. Simply
7688 resume (ecs
->event_thread
->suspend
.stop_signal
);
7690 else if (step_over_info_valid_p ())
7692 /* Another thread is stepping over a breakpoint in-line. If
7693 this thread needs a step-over too, queue the request. In
7694 either case, this resume must be deferred for later. */
7695 struct thread_info
*tp
= ecs
->event_thread
;
7697 if (ecs
->hit_singlestep_breakpoint
7698 || thread_still_needs_step_over (tp
))
7701 fprintf_unfiltered (gdb_stdlog
,
7702 "infrun: step-over already in progress: "
7703 "step-over for %s deferred\n",
7704 target_pid_to_str (tp
->ptid
));
7705 thread_step_over_chain_enqueue (tp
);
7710 fprintf_unfiltered (gdb_stdlog
,
7711 "infrun: step-over in progress: "
7712 "resume of %s deferred\n",
7713 target_pid_to_str (tp
->ptid
));
7718 struct regcache
*regcache
= get_current_regcache ();
7721 step_over_what step_what
;
7723 /* Either the trap was not expected, but we are continuing
7724 anyway (if we got a signal, the user asked it be passed to
7727 We got our expected trap, but decided we should resume from
7730 We're going to run this baby now!
7732 Note that insert_breakpoints won't try to re-insert
7733 already inserted breakpoints. Therefore, we don't
7734 care if breakpoints were already inserted, or not. */
7736 /* If we need to step over a breakpoint, and we're not using
7737 displaced stepping to do so, insert all breakpoints
7738 (watchpoints, etc.) but the one we're stepping over, step one
7739 instruction, and then re-insert the breakpoint when that step
7742 step_what
= thread_still_needs_step_over (ecs
->event_thread
);
7744 remove_bp
= (ecs
->hit_singlestep_breakpoint
7745 || (step_what
& STEP_OVER_BREAKPOINT
));
7746 remove_wps
= (step_what
& STEP_OVER_WATCHPOINT
);
7748 /* We can't use displaced stepping if we need to step past a
7749 watchpoint. The instruction copied to the scratch pad would
7750 still trigger the watchpoint. */
7752 && (remove_wps
|| !use_displaced_stepping (ecs
->event_thread
)))
7754 set_step_over_info (regcache
->aspace (),
7755 regcache_read_pc (regcache
), remove_wps
,
7756 ecs
->event_thread
->global_num
);
7758 else if (remove_wps
)
7759 set_step_over_info (NULL
, 0, remove_wps
, -1);
7761 /* If we now need to do an in-line step-over, we need to stop
7762 all other threads. Note this must be done before
7763 insert_breakpoints below, because that removes the breakpoint
7764 we're about to step over, otherwise other threads could miss
7766 if (step_over_info_valid_p () && target_is_non_stop_p ())
7767 stop_all_threads ();
7769 /* Stop stepping if inserting breakpoints fails. */
7772 insert_breakpoints ();
7774 CATCH (e
, RETURN_MASK_ERROR
)
7776 exception_print (gdb_stderr
, e
);
7778 clear_step_over_info ();
7783 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
7785 resume (ecs
->event_thread
->suspend
.stop_signal
);
7788 prepare_to_wait (ecs
);
7791 /* Called when we should continue running the inferior, because the
7792 current event doesn't cause a user visible stop. This does the
7793 resuming part; waiting for the next event is done elsewhere. */
7796 keep_going (struct execution_control_state
*ecs
)
7798 if (ecs
->event_thread
->control
.trap_expected
7799 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
7800 ecs
->event_thread
->control
.trap_expected
= 0;
7802 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7803 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7804 keep_going_pass_signal (ecs
);
7807 /* This function normally comes after a resume, before
7808 handle_inferior_event exits. It takes care of any last bits of
7809 housekeeping, and sets the all-important wait_some_more flag. */
7812 prepare_to_wait (struct execution_control_state
*ecs
)
7815 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
7817 ecs
->wait_some_more
= 1;
7819 if (!target_is_async_p ())
7820 mark_infrun_async_event_handler ();
7823 /* We are done with the step range of a step/next/si/ni command.
7824 Called once for each n of a "step n" operation. */
7827 end_stepping_range (struct execution_control_state
*ecs
)
7829 ecs
->event_thread
->control
.stop_step
= 1;
7833 /* Several print_*_reason functions to print why the inferior has stopped.
7834 We always print something when the inferior exits, or receives a signal.
7835 The rest of the cases are dealt with later on in normal_stop and
7836 print_it_typical. Ideally there should be a call to one of these
7837 print_*_reason functions functions from handle_inferior_event each time
7838 stop_waiting is called.
7840 Note that we don't call these directly, instead we delegate that to
7841 the interpreters, through observers. Interpreters then call these
7842 with whatever uiout is right. */
7845 print_end_stepping_range_reason (struct ui_out
*uiout
)
7847 /* For CLI-like interpreters, print nothing. */
7849 if (uiout
->is_mi_like_p ())
7851 uiout
->field_string ("reason",
7852 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
7857 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7859 annotate_signalled ();
7860 if (uiout
->is_mi_like_p ())
7862 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
7863 uiout
->text ("\nProgram terminated with signal ");
7864 annotate_signal_name ();
7865 uiout
->field_string ("signal-name",
7866 gdb_signal_to_name (siggnal
));
7867 annotate_signal_name_end ();
7869 annotate_signal_string ();
7870 uiout
->field_string ("signal-meaning",
7871 gdb_signal_to_string (siggnal
));
7872 annotate_signal_string_end ();
7873 uiout
->text (".\n");
7874 uiout
->text ("The program no longer exists.\n");
7878 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
7880 struct inferior
*inf
= current_inferior ();
7881 const char *pidstr
= target_pid_to_str (pid_to_ptid (inf
->pid
));
7883 annotate_exited (exitstatus
);
7886 if (uiout
->is_mi_like_p ())
7887 uiout
->field_string ("reason", async_reason_lookup (EXEC_ASYNC_EXITED
));
7888 uiout
->text ("[Inferior ");
7889 uiout
->text (plongest (inf
->num
));
7891 uiout
->text (pidstr
);
7892 uiout
->text (") exited with code ");
7893 uiout
->field_fmt ("exit-code", "0%o", (unsigned int) exitstatus
);
7894 uiout
->text ("]\n");
7898 if (uiout
->is_mi_like_p ())
7900 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
7901 uiout
->text ("[Inferior ");
7902 uiout
->text (plongest (inf
->num
));
7904 uiout
->text (pidstr
);
7905 uiout
->text (") exited normally]\n");
7909 /* Some targets/architectures can do extra processing/display of
7910 segmentation faults. E.g., Intel MPX boundary faults.
7911 Call the architecture dependent function to handle the fault. */
7914 handle_segmentation_fault (struct ui_out
*uiout
)
7916 struct regcache
*regcache
= get_current_regcache ();
7917 struct gdbarch
*gdbarch
= regcache
->arch ();
7919 if (gdbarch_handle_segmentation_fault_p (gdbarch
))
7920 gdbarch_handle_segmentation_fault (gdbarch
, uiout
);
7924 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7926 struct thread_info
*thr
= inferior_thread ();
7930 if (uiout
->is_mi_like_p ())
7932 else if (show_thread_that_caused_stop ())
7936 uiout
->text ("\nThread ");
7937 uiout
->field_fmt ("thread-id", "%s", print_thread_id (thr
));
7939 name
= thr
->name
!= NULL
? thr
->name
: target_thread_name (thr
);
7942 uiout
->text (" \"");
7943 uiout
->field_fmt ("name", "%s", name
);
7948 uiout
->text ("\nProgram");
7950 if (siggnal
== GDB_SIGNAL_0
&& !uiout
->is_mi_like_p ())
7951 uiout
->text (" stopped");
7954 uiout
->text (" received signal ");
7955 annotate_signal_name ();
7956 if (uiout
->is_mi_like_p ())
7958 ("reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
7959 uiout
->field_string ("signal-name", gdb_signal_to_name (siggnal
));
7960 annotate_signal_name_end ();
7962 annotate_signal_string ();
7963 uiout
->field_string ("signal-meaning", gdb_signal_to_string (siggnal
));
7965 if (siggnal
== GDB_SIGNAL_SEGV
)
7966 handle_segmentation_fault (uiout
);
7968 annotate_signal_string_end ();
7970 uiout
->text (".\n");
7974 print_no_history_reason (struct ui_out
*uiout
)
7976 uiout
->text ("\nNo more reverse-execution history.\n");
7979 /* Print current location without a level number, if we have changed
7980 functions or hit a breakpoint. Print source line if we have one.
7981 bpstat_print contains the logic deciding in detail what to print,
7982 based on the event(s) that just occurred. */
7985 print_stop_location (struct target_waitstatus
*ws
)
7988 enum print_what source_flag
;
7989 int do_frame_printing
= 1;
7990 struct thread_info
*tp
= inferior_thread ();
7992 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
7996 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
7997 should) carry around the function and does (or should) use
7998 that when doing a frame comparison. */
7999 if (tp
->control
.stop_step
8000 && frame_id_eq (tp
->control
.step_frame_id
,
8001 get_frame_id (get_current_frame ()))
8002 && tp
->control
.step_start_function
== find_pc_function (stop_pc
))
8004 /* Finished step, just print source line. */
8005 source_flag
= SRC_LINE
;
8009 /* Print location and source line. */
8010 source_flag
= SRC_AND_LOC
;
8013 case PRINT_SRC_AND_LOC
:
8014 /* Print location and source line. */
8015 source_flag
= SRC_AND_LOC
;
8017 case PRINT_SRC_ONLY
:
8018 source_flag
= SRC_LINE
;
8021 /* Something bogus. */
8022 source_flag
= SRC_LINE
;
8023 do_frame_printing
= 0;
8026 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
8029 /* The behavior of this routine with respect to the source
8031 SRC_LINE: Print only source line
8032 LOCATION: Print only location
8033 SRC_AND_LOC: Print location and source line. */
8034 if (do_frame_printing
)
8035 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
8041 print_stop_event (struct ui_out
*uiout
)
8043 struct target_waitstatus last
;
8045 struct thread_info
*tp
;
8047 get_last_target_status (&last_ptid
, &last
);
8050 scoped_restore save_uiout
= make_scoped_restore (¤t_uiout
, uiout
);
8052 print_stop_location (&last
);
8054 /* Display the auto-display expressions. */
8058 tp
= inferior_thread ();
8059 if (tp
->thread_fsm
!= NULL
8060 && thread_fsm_finished_p (tp
->thread_fsm
))
8062 struct return_value_info
*rv
;
8064 rv
= thread_fsm_return_value (tp
->thread_fsm
);
8066 print_return_value (uiout
, rv
);
8073 maybe_remove_breakpoints (void)
8075 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
8077 if (remove_breakpoints ())
8079 target_terminal::ours_for_output ();
8080 printf_filtered (_("Cannot remove breakpoints because "
8081 "program is no longer writable.\nFurther "
8082 "execution is probably impossible.\n"));
8087 /* The execution context that just caused a normal stop. */
8094 /* The event PTID. */
8098 /* If stopp for a thread event, this is the thread that caused the
8100 struct thread_info
*thread
;
8102 /* The inferior that caused the stop. */
8106 /* Returns a new stop context. If stopped for a thread event, this
8107 takes a strong reference to the thread. */
8109 static struct stop_context
*
8110 save_stop_context (void)
8112 struct stop_context
*sc
= XNEW (struct stop_context
);
8114 sc
->stop_id
= get_stop_id ();
8115 sc
->ptid
= inferior_ptid
;
8116 sc
->inf_num
= current_inferior ()->num
;
8118 if (!ptid_equal (inferior_ptid
, null_ptid
))
8120 /* Take a strong reference so that the thread can't be deleted
8122 sc
->thread
= inferior_thread ();
8123 sc
->thread
->incref ();
8131 /* Release a stop context previously created with save_stop_context.
8132 Releases the strong reference to the thread as well. */
8135 release_stop_context_cleanup (void *arg
)
8137 struct stop_context
*sc
= (struct stop_context
*) arg
;
8139 if (sc
->thread
!= NULL
)
8140 sc
->thread
->decref ();
8144 /* Return true if the current context no longer matches the saved stop
8148 stop_context_changed (struct stop_context
*prev
)
8150 if (!ptid_equal (prev
->ptid
, inferior_ptid
))
8152 if (prev
->inf_num
!= current_inferior ()->num
)
8154 if (prev
->thread
!= NULL
&& prev
->thread
->state
!= THREAD_STOPPED
)
8156 if (get_stop_id () != prev
->stop_id
)
8166 struct target_waitstatus last
;
8168 struct cleanup
*old_chain
= make_cleanup (null_cleanup
, NULL
);
8171 get_last_target_status (&last_ptid
, &last
);
8175 /* If an exception is thrown from this point on, make sure to
8176 propagate GDB's knowledge of the executing state to the
8177 frontend/user running state. A QUIT is an easy exception to see
8178 here, so do this before any filtered output. */
8180 make_cleanup (finish_thread_state_cleanup
, &minus_one_ptid
);
8181 else if (last
.kind
== TARGET_WAITKIND_SIGNALLED
8182 || last
.kind
== TARGET_WAITKIND_EXITED
)
8184 /* On some targets, we may still have live threads in the
8185 inferior when we get a process exit event. E.g., for
8186 "checkpoint", when the current checkpoint/fork exits,
8187 linux-fork.c automatically switches to another fork from
8188 within target_mourn_inferior. */
8189 if (!ptid_equal (inferior_ptid
, null_ptid
))
8191 pid_ptid
= pid_to_ptid (ptid_get_pid (inferior_ptid
));
8192 make_cleanup (finish_thread_state_cleanup
, &pid_ptid
);
8195 else if (last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8196 make_cleanup (finish_thread_state_cleanup
, &inferior_ptid
);
8198 /* As we're presenting a stop, and potentially removing breakpoints,
8199 update the thread list so we can tell whether there are threads
8200 running on the target. With target remote, for example, we can
8201 only learn about new threads when we explicitly update the thread
8202 list. Do this before notifying the interpreters about signal
8203 stops, end of stepping ranges, etc., so that the "new thread"
8204 output is emitted before e.g., "Program received signal FOO",
8205 instead of after. */
8206 update_thread_list ();
8208 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
8209 gdb::observers::signal_received
.notify (inferior_thread ()->suspend
.stop_signal
);
8211 /* As with the notification of thread events, we want to delay
8212 notifying the user that we've switched thread context until
8213 the inferior actually stops.
8215 There's no point in saying anything if the inferior has exited.
8216 Note that SIGNALLED here means "exited with a signal", not
8217 "received a signal".
8219 Also skip saying anything in non-stop mode. In that mode, as we
8220 don't want GDB to switch threads behind the user's back, to avoid
8221 races where the user is typing a command to apply to thread x,
8222 but GDB switches to thread y before the user finishes entering
8223 the command, fetch_inferior_event installs a cleanup to restore
8224 the current thread back to the thread the user had selected right
8225 after this event is handled, so we're not really switching, only
8226 informing of a stop. */
8228 && !ptid_equal (previous_inferior_ptid
, inferior_ptid
)
8229 && target_has_execution
8230 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
8231 && last
.kind
!= TARGET_WAITKIND_EXITED
8232 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8234 SWITCH_THRU_ALL_UIS ()
8236 target_terminal::ours_for_output ();
8237 printf_filtered (_("[Switching to %s]\n"),
8238 target_pid_to_str (inferior_ptid
));
8239 annotate_thread_changed ();
8241 previous_inferior_ptid
= inferior_ptid
;
8244 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
8246 SWITCH_THRU_ALL_UIS ()
8247 if (current_ui
->prompt_state
== PROMPT_BLOCKED
)
8249 target_terminal::ours_for_output ();
8250 printf_filtered (_("No unwaited-for children left.\n"));
8254 /* Note: this depends on the update_thread_list call above. */
8255 maybe_remove_breakpoints ();
8257 /* If an auto-display called a function and that got a signal,
8258 delete that auto-display to avoid an infinite recursion. */
8260 if (stopped_by_random_signal
)
8261 disable_current_display ();
8263 SWITCH_THRU_ALL_UIS ()
8265 async_enable_stdin ();
8268 /* Let the user/frontend see the threads as stopped. */
8269 do_cleanups (old_chain
);
8271 /* Select innermost stack frame - i.e., current frame is frame 0,
8272 and current location is based on that. Handle the case where the
8273 dummy call is returning after being stopped. E.g. the dummy call
8274 previously hit a breakpoint. (If the dummy call returns
8275 normally, we won't reach here.) Do this before the stop hook is
8276 run, so that it doesn't get to see the temporary dummy frame,
8277 which is not where we'll present the stop. */
8278 if (has_stack_frames ())
8280 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
8282 /* Pop the empty frame that contains the stack dummy. This
8283 also restores inferior state prior to the call (struct
8284 infcall_suspend_state). */
8285 struct frame_info
*frame
= get_current_frame ();
8287 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
8289 /* frame_pop calls reinit_frame_cache as the last thing it
8290 does which means there's now no selected frame. */
8293 select_frame (get_current_frame ());
8295 /* Set the current source location. */
8296 set_current_sal_from_frame (get_current_frame ());
8299 /* Look up the hook_stop and run it (CLI internally handles problem
8300 of stop_command's pre-hook not existing). */
8301 if (stop_command
!= NULL
)
8303 struct stop_context
*saved_context
= save_stop_context ();
8304 struct cleanup
*old_chain
8305 = make_cleanup (release_stop_context_cleanup
, saved_context
);
8309 execute_cmd_pre_hook (stop_command
);
8311 CATCH (ex
, RETURN_MASK_ALL
)
8313 exception_fprintf (gdb_stderr
, ex
,
8314 "Error while running hook_stop:\n");
8318 /* If the stop hook resumes the target, then there's no point in
8319 trying to notify about the previous stop; its context is
8320 gone. Likewise if the command switches thread or inferior --
8321 the observers would print a stop for the wrong
8323 if (stop_context_changed (saved_context
))
8325 do_cleanups (old_chain
);
8328 do_cleanups (old_chain
);
8331 /* Notify observers about the stop. This is where the interpreters
8332 print the stop event. */
8333 if (!ptid_equal (inferior_ptid
, null_ptid
))
8334 gdb::observers::normal_stop
.notify (inferior_thread ()->control
.stop_bpstat
,
8337 gdb::observers::normal_stop
.notify (NULL
, stop_print_frame
);
8339 annotate_stopped ();
8341 if (target_has_execution
)
8343 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
8344 && last
.kind
!= TARGET_WAITKIND_EXITED
)
8345 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8346 Delete any breakpoint that is to be deleted at the next stop. */
8347 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
8350 /* Try to get rid of automatically added inferiors that are no
8351 longer needed. Keeping those around slows down things linearly.
8352 Note that this never removes the current inferior. */
8359 signal_stop_state (int signo
)
8361 return signal_stop
[signo
];
8365 signal_print_state (int signo
)
8367 return signal_print
[signo
];
8371 signal_pass_state (int signo
)
8373 return signal_program
[signo
];
8377 signal_cache_update (int signo
)
8381 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
8382 signal_cache_update (signo
);
8387 signal_pass
[signo
] = (signal_stop
[signo
] == 0
8388 && signal_print
[signo
] == 0
8389 && signal_program
[signo
] == 1
8390 && signal_catch
[signo
] == 0);
8394 signal_stop_update (int signo
, int state
)
8396 int ret
= signal_stop
[signo
];
8398 signal_stop
[signo
] = state
;
8399 signal_cache_update (signo
);
8404 signal_print_update (int signo
, int state
)
8406 int ret
= signal_print
[signo
];
8408 signal_print
[signo
] = state
;
8409 signal_cache_update (signo
);
8414 signal_pass_update (int signo
, int state
)
8416 int ret
= signal_program
[signo
];
8418 signal_program
[signo
] = state
;
8419 signal_cache_update (signo
);
8423 /* Update the global 'signal_catch' from INFO and notify the
8427 signal_catch_update (const unsigned int *info
)
8431 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
8432 signal_catch
[i
] = info
[i
] > 0;
8433 signal_cache_update (-1);
8434 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8438 sig_print_header (void)
8440 printf_filtered (_("Signal Stop\tPrint\tPass "
8441 "to program\tDescription\n"));
8445 sig_print_info (enum gdb_signal oursig
)
8447 const char *name
= gdb_signal_to_name (oursig
);
8448 int name_padding
= 13 - strlen (name
);
8450 if (name_padding
<= 0)
8453 printf_filtered ("%s", name
);
8454 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
8455 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
8456 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
8457 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
8458 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
8461 /* Specify how various signals in the inferior should be handled. */
8464 handle_command (const char *args
, int from_tty
)
8466 int digits
, wordlen
;
8467 int sigfirst
, signum
, siglast
;
8468 enum gdb_signal oursig
;
8471 unsigned char *sigs
;
8475 error_no_arg (_("signal to handle"));
8478 /* Allocate and zero an array of flags for which signals to handle. */
8480 nsigs
= (int) GDB_SIGNAL_LAST
;
8481 sigs
= (unsigned char *) alloca (nsigs
);
8482 memset (sigs
, 0, nsigs
);
8484 /* Break the command line up into args. */
8486 gdb_argv
built_argv (args
);
8488 /* Walk through the args, looking for signal oursigs, signal names, and
8489 actions. Signal numbers and signal names may be interspersed with
8490 actions, with the actions being performed for all signals cumulatively
8491 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8493 for (char *arg
: built_argv
)
8495 wordlen
= strlen (arg
);
8496 for (digits
= 0; isdigit (arg
[digits
]); digits
++)
8500 sigfirst
= siglast
= -1;
8502 if (wordlen
>= 1 && !strncmp (arg
, "all", wordlen
))
8504 /* Apply action to all signals except those used by the
8505 debugger. Silently skip those. */
8508 siglast
= nsigs
- 1;
8510 else if (wordlen
>= 1 && !strncmp (arg
, "stop", wordlen
))
8512 SET_SIGS (nsigs
, sigs
, signal_stop
);
8513 SET_SIGS (nsigs
, sigs
, signal_print
);
8515 else if (wordlen
>= 1 && !strncmp (arg
, "ignore", wordlen
))
8517 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8519 else if (wordlen
>= 2 && !strncmp (arg
, "print", wordlen
))
8521 SET_SIGS (nsigs
, sigs
, signal_print
);
8523 else if (wordlen
>= 2 && !strncmp (arg
, "pass", wordlen
))
8525 SET_SIGS (nsigs
, sigs
, signal_program
);
8527 else if (wordlen
>= 3 && !strncmp (arg
, "nostop", wordlen
))
8529 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8531 else if (wordlen
>= 3 && !strncmp (arg
, "noignore", wordlen
))
8533 SET_SIGS (nsigs
, sigs
, signal_program
);
8535 else if (wordlen
>= 4 && !strncmp (arg
, "noprint", wordlen
))
8537 UNSET_SIGS (nsigs
, sigs
, signal_print
);
8538 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8540 else if (wordlen
>= 4 && !strncmp (arg
, "nopass", wordlen
))
8542 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8544 else if (digits
> 0)
8546 /* It is numeric. The numeric signal refers to our own
8547 internal signal numbering from target.h, not to host/target
8548 signal number. This is a feature; users really should be
8549 using symbolic names anyway, and the common ones like
8550 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8552 sigfirst
= siglast
= (int)
8553 gdb_signal_from_command (atoi (arg
));
8554 if (arg
[digits
] == '-')
8557 gdb_signal_from_command (atoi (arg
+ digits
+ 1));
8559 if (sigfirst
> siglast
)
8561 /* Bet he didn't figure we'd think of this case... */
8569 oursig
= gdb_signal_from_name (arg
);
8570 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
8572 sigfirst
= siglast
= (int) oursig
;
8576 /* Not a number and not a recognized flag word => complain. */
8577 error (_("Unrecognized or ambiguous flag word: \"%s\"."), arg
);
8581 /* If any signal numbers or symbol names were found, set flags for
8582 which signals to apply actions to. */
8584 for (signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
8586 switch ((enum gdb_signal
) signum
)
8588 case GDB_SIGNAL_TRAP
:
8589 case GDB_SIGNAL_INT
:
8590 if (!allsigs
&& !sigs
[signum
])
8592 if (query (_("%s is used by the debugger.\n\
8593 Are you sure you want to change it? "),
8594 gdb_signal_to_name ((enum gdb_signal
) signum
)))
8600 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8601 gdb_flush (gdb_stdout
);
8606 case GDB_SIGNAL_DEFAULT
:
8607 case GDB_SIGNAL_UNKNOWN
:
8608 /* Make sure that "all" doesn't print these. */
8617 for (signum
= 0; signum
< nsigs
; signum
++)
8620 signal_cache_update (-1);
8621 target_pass_signals ((int) GDB_SIGNAL_LAST
, signal_pass
);
8622 target_program_signals ((int) GDB_SIGNAL_LAST
, signal_program
);
8626 /* Show the results. */
8627 sig_print_header ();
8628 for (; signum
< nsigs
; signum
++)
8630 sig_print_info ((enum gdb_signal
) signum
);
8637 /* Complete the "handle" command. */
8640 handle_completer (struct cmd_list_element
*ignore
,
8641 completion_tracker
&tracker
,
8642 const char *text
, const char *word
)
8644 static const char * const keywords
[] =
8658 signal_completer (ignore
, tracker
, text
, word
);
8659 complete_on_enum (tracker
, keywords
, word
, word
);
8663 gdb_signal_from_command (int num
)
8665 if (num
>= 1 && num
<= 15)
8666 return (enum gdb_signal
) num
;
8667 error (_("Only signals 1-15 are valid as numeric signals.\n\
8668 Use \"info signals\" for a list of symbolic signals."));
8671 /* Print current contents of the tables set by the handle command.
8672 It is possible we should just be printing signals actually used
8673 by the current target (but for things to work right when switching
8674 targets, all signals should be in the signal tables). */
8677 info_signals_command (const char *signum_exp
, int from_tty
)
8679 enum gdb_signal oursig
;
8681 sig_print_header ();
8685 /* First see if this is a symbol name. */
8686 oursig
= gdb_signal_from_name (signum_exp
);
8687 if (oursig
== GDB_SIGNAL_UNKNOWN
)
8689 /* No, try numeric. */
8691 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
8693 sig_print_info (oursig
);
8697 printf_filtered ("\n");
8698 /* These ugly casts brought to you by the native VAX compiler. */
8699 for (oursig
= GDB_SIGNAL_FIRST
;
8700 (int) oursig
< (int) GDB_SIGNAL_LAST
;
8701 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
8705 if (oursig
!= GDB_SIGNAL_UNKNOWN
8706 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
8707 sig_print_info (oursig
);
8710 printf_filtered (_("\nUse the \"handle\" command "
8711 "to change these tables.\n"));
8714 /* The $_siginfo convenience variable is a bit special. We don't know
8715 for sure the type of the value until we actually have a chance to
8716 fetch the data. The type can change depending on gdbarch, so it is
8717 also dependent on which thread you have selected.
8719 1. making $_siginfo be an internalvar that creates a new value on
8722 2. making the value of $_siginfo be an lval_computed value. */
8724 /* This function implements the lval_computed support for reading a
8728 siginfo_value_read (struct value
*v
)
8730 LONGEST transferred
;
8732 /* If we can access registers, so can we access $_siginfo. Likewise
8734 validate_registers_access ();
8737 target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
,
8739 value_contents_all_raw (v
),
8741 TYPE_LENGTH (value_type (v
)));
8743 if (transferred
!= TYPE_LENGTH (value_type (v
)))
8744 error (_("Unable to read siginfo"));
8747 /* This function implements the lval_computed support for writing a
8751 siginfo_value_write (struct value
*v
, struct value
*fromval
)
8753 LONGEST transferred
;
8755 /* If we can access registers, so can we access $_siginfo. Likewise
8757 validate_registers_access ();
8759 transferred
= target_write (¤t_target
,
8760 TARGET_OBJECT_SIGNAL_INFO
,
8762 value_contents_all_raw (fromval
),
8764 TYPE_LENGTH (value_type (fromval
)));
8766 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
8767 error (_("Unable to write siginfo"));
8770 static const struct lval_funcs siginfo_value_funcs
=
8776 /* Return a new value with the correct type for the siginfo object of
8777 the current thread using architecture GDBARCH. Return a void value
8778 if there's no object available. */
8780 static struct value
*
8781 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
8784 if (target_has_stack
8785 && !ptid_equal (inferior_ptid
, null_ptid
)
8786 && gdbarch_get_siginfo_type_p (gdbarch
))
8788 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8790 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
8793 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
8797 /* infcall_suspend_state contains state about the program itself like its
8798 registers and any signal it received when it last stopped.
8799 This state must be restored regardless of how the inferior function call
8800 ends (either successfully, or after it hits a breakpoint or signal)
8801 if the program is to properly continue where it left off. */
8803 struct infcall_suspend_state
8805 struct thread_suspend_state thread_suspend
;
8809 readonly_detached_regcache
*registers
;
8811 /* Format of SIGINFO_DATA or NULL if it is not present. */
8812 struct gdbarch
*siginfo_gdbarch
;
8814 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
8815 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
8816 content would be invalid. */
8817 gdb_byte
*siginfo_data
;
8820 struct infcall_suspend_state
*
8821 save_infcall_suspend_state (void)
8823 struct infcall_suspend_state
*inf_state
;
8824 struct thread_info
*tp
= inferior_thread ();
8825 struct regcache
*regcache
= get_current_regcache ();
8826 struct gdbarch
*gdbarch
= regcache
->arch ();
8827 gdb_byte
*siginfo_data
= NULL
;
8829 if (gdbarch_get_siginfo_type_p (gdbarch
))
8831 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8832 size_t len
= TYPE_LENGTH (type
);
8833 struct cleanup
*back_to
;
8835 siginfo_data
= (gdb_byte
*) xmalloc (len
);
8836 back_to
= make_cleanup (xfree
, siginfo_data
);
8838 if (target_read (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8839 siginfo_data
, 0, len
) == len
)
8840 discard_cleanups (back_to
);
8843 /* Errors ignored. */
8844 do_cleanups (back_to
);
8845 siginfo_data
= NULL
;
8849 inf_state
= XCNEW (struct infcall_suspend_state
);
8853 inf_state
->siginfo_gdbarch
= gdbarch
;
8854 inf_state
->siginfo_data
= siginfo_data
;
8857 inf_state
->thread_suspend
= tp
->suspend
;
8859 /* run_inferior_call will not use the signal due to its `proceed' call with
8860 GDB_SIGNAL_0 anyway. */
8861 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
8863 inf_state
->stop_pc
= stop_pc
;
8865 inf_state
->registers
= new readonly_detached_regcache (*regcache
);
8870 /* Restore inferior session state to INF_STATE. */
8873 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8875 struct thread_info
*tp
= inferior_thread ();
8876 struct regcache
*regcache
= get_current_regcache ();
8877 struct gdbarch
*gdbarch
= regcache
->arch ();
8879 tp
->suspend
= inf_state
->thread_suspend
;
8881 stop_pc
= inf_state
->stop_pc
;
8883 if (inf_state
->siginfo_gdbarch
== gdbarch
)
8885 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8887 /* Errors ignored. */
8888 target_write (¤t_target
, TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8889 inf_state
->siginfo_data
, 0, TYPE_LENGTH (type
));
8892 /* The inferior can be gone if the user types "print exit(0)"
8893 (and perhaps other times). */
8894 if (target_has_execution
)
8895 /* NB: The register write goes through to the target. */
8896 regcache
->restore (inf_state
->registers
);
8898 discard_infcall_suspend_state (inf_state
);
8902 do_restore_infcall_suspend_state_cleanup (void *state
)
8904 restore_infcall_suspend_state ((struct infcall_suspend_state
*) state
);
8908 make_cleanup_restore_infcall_suspend_state
8909 (struct infcall_suspend_state
*inf_state
)
8911 return make_cleanup (do_restore_infcall_suspend_state_cleanup
, inf_state
);
8915 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8917 delete inf_state
->registers
;
8918 xfree (inf_state
->siginfo_data
);
8922 readonly_detached_regcache
*
8923 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
8925 return inf_state
->registers
;
8928 /* infcall_control_state contains state regarding gdb's control of the
8929 inferior itself like stepping control. It also contains session state like
8930 the user's currently selected frame. */
8932 struct infcall_control_state
8934 struct thread_control_state thread_control
;
8935 struct inferior_control_state inferior_control
;
8938 enum stop_stack_kind stop_stack_dummy
;
8939 int stopped_by_random_signal
;
8941 /* ID if the selected frame when the inferior function call was made. */
8942 struct frame_id selected_frame_id
;
8945 /* Save all of the information associated with the inferior<==>gdb
8948 struct infcall_control_state
*
8949 save_infcall_control_state (void)
8951 struct infcall_control_state
*inf_status
=
8952 XNEW (struct infcall_control_state
);
8953 struct thread_info
*tp
= inferior_thread ();
8954 struct inferior
*inf
= current_inferior ();
8956 inf_status
->thread_control
= tp
->control
;
8957 inf_status
->inferior_control
= inf
->control
;
8959 tp
->control
.step_resume_breakpoint
= NULL
;
8960 tp
->control
.exception_resume_breakpoint
= NULL
;
8962 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
8963 chain. If caller's caller is walking the chain, they'll be happier if we
8964 hand them back the original chain when restore_infcall_control_state is
8966 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
8969 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
8970 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
8972 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
8978 restore_selected_frame (const frame_id
&fid
)
8980 frame_info
*frame
= frame_find_by_id (fid
);
8982 /* If inf_status->selected_frame_id is NULL, there was no previously
8986 warning (_("Unable to restore previously selected frame."));
8990 select_frame (frame
);
8993 /* Restore inferior session state to INF_STATUS. */
8996 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
8998 struct thread_info
*tp
= inferior_thread ();
8999 struct inferior
*inf
= current_inferior ();
9001 if (tp
->control
.step_resume_breakpoint
)
9002 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
9004 if (tp
->control
.exception_resume_breakpoint
)
9005 tp
->control
.exception_resume_breakpoint
->disposition
9006 = disp_del_at_next_stop
;
9008 /* Handle the bpstat_copy of the chain. */
9009 bpstat_clear (&tp
->control
.stop_bpstat
);
9011 tp
->control
= inf_status
->thread_control
;
9012 inf
->control
= inf_status
->inferior_control
;
9015 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
9016 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
9018 if (target_has_stack
)
9020 /* The point of the try/catch is that if the stack is clobbered,
9021 walking the stack might encounter a garbage pointer and
9022 error() trying to dereference it. */
9025 restore_selected_frame (inf_status
->selected_frame_id
);
9027 CATCH (ex
, RETURN_MASK_ERROR
)
9029 exception_fprintf (gdb_stderr
, ex
,
9030 "Unable to restore previously selected frame:\n");
9031 /* Error in restoring the selected frame. Select the
9033 select_frame (get_current_frame ());
9042 do_restore_infcall_control_state_cleanup (void *sts
)
9044 restore_infcall_control_state ((struct infcall_control_state
*) sts
);
9048 make_cleanup_restore_infcall_control_state
9049 (struct infcall_control_state
*inf_status
)
9051 return make_cleanup (do_restore_infcall_control_state_cleanup
, inf_status
);
9055 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
9057 if (inf_status
->thread_control
.step_resume_breakpoint
)
9058 inf_status
->thread_control
.step_resume_breakpoint
->disposition
9059 = disp_del_at_next_stop
;
9061 if (inf_status
->thread_control
.exception_resume_breakpoint
)
9062 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
9063 = disp_del_at_next_stop
;
9065 /* See save_infcall_control_state for info on stop_bpstat. */
9066 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
9074 clear_exit_convenience_vars (void)
9076 clear_internalvar (lookup_internalvar ("_exitsignal"));
9077 clear_internalvar (lookup_internalvar ("_exitcode"));
9081 /* User interface for reverse debugging:
9082 Set exec-direction / show exec-direction commands
9083 (returns error unless target implements to_set_exec_direction method). */
9085 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
9086 static const char exec_forward
[] = "forward";
9087 static const char exec_reverse
[] = "reverse";
9088 static const char *exec_direction
= exec_forward
;
9089 static const char *const exec_direction_names
[] = {
9096 set_exec_direction_func (const char *args
, int from_tty
,
9097 struct cmd_list_element
*cmd
)
9099 if (target_can_execute_reverse
)
9101 if (!strcmp (exec_direction
, exec_forward
))
9102 execution_direction
= EXEC_FORWARD
;
9103 else if (!strcmp (exec_direction
, exec_reverse
))
9104 execution_direction
= EXEC_REVERSE
;
9108 exec_direction
= exec_forward
;
9109 error (_("Target does not support this operation."));
9114 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
9115 struct cmd_list_element
*cmd
, const char *value
)
9117 switch (execution_direction
) {
9119 fprintf_filtered (out
, _("Forward.\n"));
9122 fprintf_filtered (out
, _("Reverse.\n"));
9125 internal_error (__FILE__
, __LINE__
,
9126 _("bogus execution_direction value: %d"),
9127 (int) execution_direction
);
9132 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
9133 struct cmd_list_element
*c
, const char *value
)
9135 fprintf_filtered (file
, _("Resuming the execution of threads "
9136 "of all processes is %s.\n"), value
);
9139 /* Implementation of `siginfo' variable. */
9141 static const struct internalvar_funcs siginfo_funcs
=
9148 /* Callback for infrun's target events source. This is marked when a
9149 thread has a pending status to process. */
9152 infrun_async_inferior_event_handler (gdb_client_data data
)
9154 inferior_event_handler (INF_REG_EVENT
, NULL
);
9158 _initialize_infrun (void)
9162 struct cmd_list_element
*c
;
9164 /* Register extra event sources in the event loop. */
9165 infrun_async_inferior_event_token
9166 = create_async_event_handler (infrun_async_inferior_event_handler
, NULL
);
9168 add_info ("signals", info_signals_command
, _("\
9169 What debugger does when program gets various signals.\n\
9170 Specify a signal as argument to print info on that signal only."));
9171 add_info_alias ("handle", "signals", 0);
9173 c
= add_com ("handle", class_run
, handle_command
, _("\
9174 Specify how to handle signals.\n\
9175 Usage: handle SIGNAL [ACTIONS]\n\
9176 Args are signals and actions to apply to those signals.\n\
9177 If no actions are specified, the current settings for the specified signals\n\
9178 will be displayed instead.\n\
9180 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
9181 from 1-15 are allowed for compatibility with old versions of GDB.\n\
9182 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
9183 The special arg \"all\" is recognized to mean all signals except those\n\
9184 used by the debugger, typically SIGTRAP and SIGINT.\n\
9186 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
9187 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
9188 Stop means reenter debugger if this signal happens (implies print).\n\
9189 Print means print a message if this signal happens.\n\
9190 Pass means let program see this signal; otherwise program doesn't know.\n\
9191 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
9192 Pass and Stop may be combined.\n\
9194 Multiple signals may be specified. Signal numbers and signal names\n\
9195 may be interspersed with actions, with the actions being performed for\n\
9196 all signals cumulatively specified."));
9197 set_cmd_completer (c
, handle_completer
);
9200 stop_command
= add_cmd ("stop", class_obscure
,
9201 not_just_help_class_command
, _("\
9202 There is no `stop' command, but you can set a hook on `stop'.\n\
9203 This allows you to set a list of commands to be run each time execution\n\
9204 of the program stops."), &cmdlist
);
9206 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
9207 Set inferior debugging."), _("\
9208 Show inferior debugging."), _("\
9209 When non-zero, inferior specific debugging is enabled."),
9212 &setdebuglist
, &showdebuglist
);
9214 add_setshow_boolean_cmd ("displaced", class_maintenance
,
9215 &debug_displaced
, _("\
9216 Set displaced stepping debugging."), _("\
9217 Show displaced stepping debugging."), _("\
9218 When non-zero, displaced stepping specific debugging is enabled."),
9220 show_debug_displaced
,
9221 &setdebuglist
, &showdebuglist
);
9223 add_setshow_boolean_cmd ("non-stop", no_class
,
9225 Set whether gdb controls the inferior in non-stop mode."), _("\
9226 Show whether gdb controls the inferior in non-stop mode."), _("\
9227 When debugging a multi-threaded program and this setting is\n\
9228 off (the default, also called all-stop mode), when one thread stops\n\
9229 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9230 all other threads in the program while you interact with the thread of\n\
9231 interest. When you continue or step a thread, you can allow the other\n\
9232 threads to run, or have them remain stopped, but while you inspect any\n\
9233 thread's state, all threads stop.\n\
9235 In non-stop mode, when one thread stops, other threads can continue\n\
9236 to run freely. You'll be able to step each thread independently,\n\
9237 leave it stopped or free to run as needed."),
9243 numsigs
= (int) GDB_SIGNAL_LAST
;
9244 signal_stop
= XNEWVEC (unsigned char, numsigs
);
9245 signal_print
= XNEWVEC (unsigned char, numsigs
);
9246 signal_program
= XNEWVEC (unsigned char, numsigs
);
9247 signal_catch
= XNEWVEC (unsigned char, numsigs
);
9248 signal_pass
= XNEWVEC (unsigned char, numsigs
);
9249 for (i
= 0; i
< numsigs
; i
++)
9252 signal_print
[i
] = 1;
9253 signal_program
[i
] = 1;
9254 signal_catch
[i
] = 0;
9257 /* Signals caused by debugger's own actions should not be given to
9258 the program afterwards.
9260 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9261 explicitly specifies that it should be delivered to the target
9262 program. Typically, that would occur when a user is debugging a
9263 target monitor on a simulator: the target monitor sets a
9264 breakpoint; the simulator encounters this breakpoint and halts
9265 the simulation handing control to GDB; GDB, noting that the stop
9266 address doesn't map to any known breakpoint, returns control back
9267 to the simulator; the simulator then delivers the hardware
9268 equivalent of a GDB_SIGNAL_TRAP to the program being
9270 signal_program
[GDB_SIGNAL_TRAP
] = 0;
9271 signal_program
[GDB_SIGNAL_INT
] = 0;
9273 /* Signals that are not errors should not normally enter the debugger. */
9274 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
9275 signal_print
[GDB_SIGNAL_ALRM
] = 0;
9276 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
9277 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
9278 signal_stop
[GDB_SIGNAL_PROF
] = 0;
9279 signal_print
[GDB_SIGNAL_PROF
] = 0;
9280 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
9281 signal_print
[GDB_SIGNAL_CHLD
] = 0;
9282 signal_stop
[GDB_SIGNAL_IO
] = 0;
9283 signal_print
[GDB_SIGNAL_IO
] = 0;
9284 signal_stop
[GDB_SIGNAL_POLL
] = 0;
9285 signal_print
[GDB_SIGNAL_POLL
] = 0;
9286 signal_stop
[GDB_SIGNAL_URG
] = 0;
9287 signal_print
[GDB_SIGNAL_URG
] = 0;
9288 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
9289 signal_print
[GDB_SIGNAL_WINCH
] = 0;
9290 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
9291 signal_print
[GDB_SIGNAL_PRIO
] = 0;
9293 /* These signals are used internally by user-level thread
9294 implementations. (See signal(5) on Solaris.) Like the above
9295 signals, a healthy program receives and handles them as part of
9296 its normal operation. */
9297 signal_stop
[GDB_SIGNAL_LWP
] = 0;
9298 signal_print
[GDB_SIGNAL_LWP
] = 0;
9299 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
9300 signal_print
[GDB_SIGNAL_WAITING
] = 0;
9301 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
9302 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
9303 signal_stop
[GDB_SIGNAL_LIBRT
] = 0;
9304 signal_print
[GDB_SIGNAL_LIBRT
] = 0;
9306 /* Update cached state. */
9307 signal_cache_update (-1);
9309 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
9310 &stop_on_solib_events
, _("\
9311 Set stopping for shared library events."), _("\
9312 Show stopping for shared library events."), _("\
9313 If nonzero, gdb will give control to the user when the dynamic linker\n\
9314 notifies gdb of shared library events. The most common event of interest\n\
9315 to the user would be loading/unloading of a new library."),
9316 set_stop_on_solib_events
,
9317 show_stop_on_solib_events
,
9318 &setlist
, &showlist
);
9320 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
9321 follow_fork_mode_kind_names
,
9322 &follow_fork_mode_string
, _("\
9323 Set debugger response to a program call of fork or vfork."), _("\
9324 Show debugger response to a program call of fork or vfork."), _("\
9325 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9326 parent - the original process is debugged after a fork\n\
9327 child - the new process is debugged after a fork\n\
9328 The unfollowed process will continue to run.\n\
9329 By default, the debugger will follow the parent process."),
9331 show_follow_fork_mode_string
,
9332 &setlist
, &showlist
);
9334 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
9335 follow_exec_mode_names
,
9336 &follow_exec_mode_string
, _("\
9337 Set debugger response to a program call of exec."), _("\
9338 Show debugger response to a program call of exec."), _("\
9339 An exec call replaces the program image of a process.\n\
9341 follow-exec-mode can be:\n\
9343 new - the debugger creates a new inferior and rebinds the process\n\
9344 to this new inferior. The program the process was running before\n\
9345 the exec call can be restarted afterwards by restarting the original\n\
9348 same - the debugger keeps the process bound to the same inferior.\n\
9349 The new executable image replaces the previous executable loaded in\n\
9350 the inferior. Restarting the inferior after the exec call restarts\n\
9351 the executable the process was running after the exec call.\n\
9353 By default, the debugger will use the same inferior."),
9355 show_follow_exec_mode_string
,
9356 &setlist
, &showlist
);
9358 add_setshow_enum_cmd ("scheduler-locking", class_run
,
9359 scheduler_enums
, &scheduler_mode
, _("\
9360 Set mode for locking scheduler during execution."), _("\
9361 Show mode for locking scheduler during execution."), _("\
9362 off == no locking (threads may preempt at any time)\n\
9363 on == full locking (no thread except the current thread may run)\n\
9364 This applies to both normal execution and replay mode.\n\
9365 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9366 In this mode, other threads may run during other commands.\n\
9367 This applies to both normal execution and replay mode.\n\
9368 replay == scheduler locked in replay mode and unlocked during normal execution."),
9369 set_schedlock_func
, /* traps on target vector */
9370 show_scheduler_mode
,
9371 &setlist
, &showlist
);
9373 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
9374 Set mode for resuming threads of all processes."), _("\
9375 Show mode for resuming threads of all processes."), _("\
9376 When on, execution commands (such as 'continue' or 'next') resume all\n\
9377 threads of all processes. When off (which is the default), execution\n\
9378 commands only resume the threads of the current process. The set of\n\
9379 threads that are resumed is further refined by the scheduler-locking\n\
9380 mode (see help set scheduler-locking)."),
9382 show_schedule_multiple
,
9383 &setlist
, &showlist
);
9385 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
9386 Set mode of the step operation."), _("\
9387 Show mode of the step operation."), _("\
9388 When set, doing a step over a function without debug line information\n\
9389 will stop at the first instruction of that function. Otherwise, the\n\
9390 function is skipped and the step command stops at a different source line."),
9392 show_step_stop_if_no_debug
,
9393 &setlist
, &showlist
);
9395 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
9396 &can_use_displaced_stepping
, _("\
9397 Set debugger's willingness to use displaced stepping."), _("\
9398 Show debugger's willingness to use displaced stepping."), _("\
9399 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9400 supported by the target architecture. If off, gdb will not use displaced\n\
9401 stepping to step over breakpoints, even if such is supported by the target\n\
9402 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9403 if the target architecture supports it and non-stop mode is active, but will not\n\
9404 use it in all-stop mode (see help set non-stop)."),
9406 show_can_use_displaced_stepping
,
9407 &setlist
, &showlist
);
9409 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
9410 &exec_direction
, _("Set direction of execution.\n\
9411 Options are 'forward' or 'reverse'."),
9412 _("Show direction of execution (forward/reverse)."),
9413 _("Tells gdb whether to execute forward or backward."),
9414 set_exec_direction_func
, show_exec_direction_func
,
9415 &setlist
, &showlist
);
9417 /* Set/show detach-on-fork: user-settable mode. */
9419 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
9420 Set whether gdb will detach the child of a fork."), _("\
9421 Show whether gdb will detach the child of a fork."), _("\
9422 Tells gdb whether to detach the child of a fork."),
9423 NULL
, NULL
, &setlist
, &showlist
);
9425 /* Set/show disable address space randomization mode. */
9427 add_setshow_boolean_cmd ("disable-randomization", class_support
,
9428 &disable_randomization
, _("\
9429 Set disabling of debuggee's virtual address space randomization."), _("\
9430 Show disabling of debuggee's virtual address space randomization."), _("\
9431 When this mode is on (which is the default), randomization of the virtual\n\
9432 address space is disabled. Standalone programs run with the randomization\n\
9433 enabled by default on some platforms."),
9434 &set_disable_randomization
,
9435 &show_disable_randomization
,
9436 &setlist
, &showlist
);
9438 /* ptid initializations */
9439 inferior_ptid
= null_ptid
;
9440 target_last_wait_ptid
= minus_one_ptid
;
9442 gdb::observers::thread_ptid_changed
.attach (infrun_thread_ptid_changed
);
9443 gdb::observers::thread_stop_requested
.attach (infrun_thread_stop_requested
);
9444 gdb::observers::thread_exit
.attach (infrun_thread_thread_exit
);
9445 gdb::observers::inferior_exit
.attach (infrun_inferior_exit
);
9447 /* Explicitly create without lookup, since that tries to create a
9448 value with a void typed value, and when we get here, gdbarch
9449 isn't initialized yet. At this point, we're quite sure there
9450 isn't another convenience variable of the same name. */
9451 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
9453 add_setshow_boolean_cmd ("observer", no_class
,
9454 &observer_mode_1
, _("\
9455 Set whether gdb controls the inferior in observer mode."), _("\
9456 Show whether gdb controls the inferior in observer mode."), _("\
9457 In observer mode, GDB can get data from the inferior, but not\n\
9458 affect its execution. Registers and memory may not be changed,\n\
9459 breakpoints may not be set, and the program cannot be interrupted\n\