1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2019 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"
28 #include "gdbsupport/gdb_wait.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 "gdbsupport/enum-flags.h"
67 #include "progspace-and-thread.h"
68 #include "gdbsupport/gdb_optional.h"
69 #include "arch-utils.h"
70 #include "gdbsupport/scope-exit.h"
71 #include "gdbsupport/forward-scope-exit.h"
73 /* Prototypes for local functions */
75 static void sig_print_info (enum gdb_signal
);
77 static void sig_print_header (void);
79 static int follow_fork (void);
81 static int follow_fork_inferior (int follow_child
, int detach_fork
);
83 static void follow_inferior_reset_breakpoints (void);
85 static int currently_stepping (struct thread_info
*tp
);
87 void nullify_last_target_wait_ptid (void);
89 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*);
91 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
93 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
95 static int maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
);
97 static void resume (gdb_signal sig
);
99 /* Asynchronous signal handler registered as event loop source for
100 when we have pending events ready to be passed to the core. */
101 static struct async_event_handler
*infrun_async_inferior_event_token
;
103 /* Stores whether infrun_async was previously enabled or disabled.
104 Starts off as -1, indicating "never enabled/disabled". */
105 static int infrun_is_async
= -1;
110 infrun_async (int enable
)
112 if (infrun_is_async
!= enable
)
114 infrun_is_async
= enable
;
117 fprintf_unfiltered (gdb_stdlog
,
118 "infrun: infrun_async(%d)\n",
122 mark_async_event_handler (infrun_async_inferior_event_token
);
124 clear_async_event_handler (infrun_async_inferior_event_token
);
131 mark_infrun_async_event_handler (void)
133 mark_async_event_handler (infrun_async_inferior_event_token
);
136 /* When set, stop the 'step' command if we enter a function which has
137 no line number information. The normal behavior is that we step
138 over such function. */
139 bool step_stop_if_no_debug
= false;
141 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
142 struct cmd_list_element
*c
, const char *value
)
144 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
147 /* proceed and normal_stop use this to notify the user when the
148 inferior stopped in a different thread than it had been running
151 static ptid_t previous_inferior_ptid
;
153 /* If set (default for legacy reasons), when following a fork, GDB
154 will detach from one of the fork branches, child or parent.
155 Exactly which branch is detached depends on 'set follow-fork-mode'
158 static bool detach_fork
= true;
160 bool debug_displaced
= false;
162 show_debug_displaced (struct ui_file
*file
, int from_tty
,
163 struct cmd_list_element
*c
, const char *value
)
165 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
168 unsigned int debug_infrun
= 0;
170 show_debug_infrun (struct ui_file
*file
, int from_tty
,
171 struct cmd_list_element
*c
, const char *value
)
173 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
177 /* Support for disabling address space randomization. */
179 bool disable_randomization
= true;
182 show_disable_randomization (struct ui_file
*file
, int from_tty
,
183 struct cmd_list_element
*c
, const char *value
)
185 if (target_supports_disable_randomization ())
186 fprintf_filtered (file
,
187 _("Disabling randomization of debuggee's "
188 "virtual address space is %s.\n"),
191 fputs_filtered (_("Disabling randomization of debuggee's "
192 "virtual address space is unsupported on\n"
193 "this platform.\n"), file
);
197 set_disable_randomization (const char *args
, int from_tty
,
198 struct cmd_list_element
*c
)
200 if (!target_supports_disable_randomization ())
201 error (_("Disabling randomization of debuggee's "
202 "virtual address space is unsupported on\n"
206 /* User interface for non-stop mode. */
208 bool non_stop
= false;
209 static bool non_stop_1
= false;
212 set_non_stop (const char *args
, int from_tty
,
213 struct cmd_list_element
*c
)
215 if (target_has_execution
)
217 non_stop_1
= non_stop
;
218 error (_("Cannot change this setting while the inferior is running."));
221 non_stop
= non_stop_1
;
225 show_non_stop (struct ui_file
*file
, int from_tty
,
226 struct cmd_list_element
*c
, const char *value
)
228 fprintf_filtered (file
,
229 _("Controlling the inferior in non-stop mode is %s.\n"),
233 /* "Observer mode" is somewhat like a more extreme version of
234 non-stop, in which all GDB operations that might affect the
235 target's execution have been disabled. */
237 bool observer_mode
= false;
238 static bool observer_mode_1
= false;
241 set_observer_mode (const char *args
, int from_tty
,
242 struct cmd_list_element
*c
)
244 if (target_has_execution
)
246 observer_mode_1
= observer_mode
;
247 error (_("Cannot change this setting while the inferior is running."));
250 observer_mode
= observer_mode_1
;
252 may_write_registers
= !observer_mode
;
253 may_write_memory
= !observer_mode
;
254 may_insert_breakpoints
= !observer_mode
;
255 may_insert_tracepoints
= !observer_mode
;
256 /* We can insert fast tracepoints in or out of observer mode,
257 but enable them if we're going into this mode. */
259 may_insert_fast_tracepoints
= true;
260 may_stop
= !observer_mode
;
261 update_target_permissions ();
263 /* Going *into* observer mode we must force non-stop, then
264 going out we leave it that way. */
267 pagination_enabled
= 0;
268 non_stop
= non_stop_1
= true;
272 printf_filtered (_("Observer mode is now %s.\n"),
273 (observer_mode
? "on" : "off"));
277 show_observer_mode (struct ui_file
*file
, int from_tty
,
278 struct cmd_list_element
*c
, const char *value
)
280 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
283 /* This updates the value of observer mode based on changes in
284 permissions. Note that we are deliberately ignoring the values of
285 may-write-registers and may-write-memory, since the user may have
286 reason to enable these during a session, for instance to turn on a
287 debugging-related global. */
290 update_observer_mode (void)
292 bool newval
= (!may_insert_breakpoints
293 && !may_insert_tracepoints
294 && may_insert_fast_tracepoints
298 /* Let the user know if things change. */
299 if (newval
!= observer_mode
)
300 printf_filtered (_("Observer mode is now %s.\n"),
301 (newval
? "on" : "off"));
303 observer_mode
= observer_mode_1
= newval
;
306 /* Tables of how to react to signals; the user sets them. */
308 static unsigned char signal_stop
[GDB_SIGNAL_LAST
];
309 static unsigned char signal_print
[GDB_SIGNAL_LAST
];
310 static unsigned char signal_program
[GDB_SIGNAL_LAST
];
312 /* Table of signals that are registered with "catch signal". A
313 non-zero entry indicates that the signal is caught by some "catch
315 static unsigned char signal_catch
[GDB_SIGNAL_LAST
];
317 /* Table of signals that the target may silently handle.
318 This is automatically determined from the flags above,
319 and simply cached here. */
320 static unsigned char signal_pass
[GDB_SIGNAL_LAST
];
322 #define SET_SIGS(nsigs,sigs,flags) \
324 int signum = (nsigs); \
325 while (signum-- > 0) \
326 if ((sigs)[signum]) \
327 (flags)[signum] = 1; \
330 #define UNSET_SIGS(nsigs,sigs,flags) \
332 int signum = (nsigs); \
333 while (signum-- > 0) \
334 if ((sigs)[signum]) \
335 (flags)[signum] = 0; \
338 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
339 this function is to avoid exporting `signal_program'. */
342 update_signals_program_target (void)
344 target_program_signals (signal_program
);
347 /* Value to pass to target_resume() to cause all threads to resume. */
349 #define RESUME_ALL minus_one_ptid
351 /* Command list pointer for the "stop" placeholder. */
353 static struct cmd_list_element
*stop_command
;
355 /* Nonzero if we want to give control to the user when we're notified
356 of shared library events by the dynamic linker. */
357 int stop_on_solib_events
;
359 /* Enable or disable optional shared library event breakpoints
360 as appropriate when the above flag is changed. */
363 set_stop_on_solib_events (const char *args
,
364 int from_tty
, struct cmd_list_element
*c
)
366 update_solib_breakpoints ();
370 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
371 struct cmd_list_element
*c
, const char *value
)
373 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
377 /* Nonzero after stop if current stack frame should be printed. */
379 static int stop_print_frame
;
381 /* This is a cached copy of the pid/waitstatus of the last event
382 returned by target_wait()/deprecated_target_wait_hook(). This
383 information is returned by get_last_target_status(). */
384 static ptid_t target_last_wait_ptid
;
385 static struct target_waitstatus target_last_waitstatus
;
387 void init_thread_stepping_state (struct thread_info
*tss
);
389 static const char follow_fork_mode_child
[] = "child";
390 static const char follow_fork_mode_parent
[] = "parent";
392 static const char *const follow_fork_mode_kind_names
[] = {
393 follow_fork_mode_child
,
394 follow_fork_mode_parent
,
398 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
400 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
401 struct cmd_list_element
*c
, const char *value
)
403 fprintf_filtered (file
,
404 _("Debugger response to a program "
405 "call of fork or vfork is \"%s\".\n"),
410 /* Handle changes to the inferior list based on the type of fork,
411 which process is being followed, and whether the other process
412 should be detached. On entry inferior_ptid must be the ptid of
413 the fork parent. At return inferior_ptid is the ptid of the
414 followed inferior. */
417 follow_fork_inferior (int follow_child
, int detach_fork
)
420 ptid_t parent_ptid
, child_ptid
;
422 has_vforked
= (inferior_thread ()->pending_follow
.kind
423 == TARGET_WAITKIND_VFORKED
);
424 parent_ptid
= inferior_ptid
;
425 child_ptid
= inferior_thread ()->pending_follow
.value
.related_pid
;
428 && !non_stop
/* Non-stop always resumes both branches. */
429 && current_ui
->prompt_state
== PROMPT_BLOCKED
430 && !(follow_child
|| detach_fork
|| sched_multi
))
432 /* The parent stays blocked inside the vfork syscall until the
433 child execs or exits. If we don't let the child run, then
434 the parent stays blocked. If we're telling the parent to run
435 in the foreground, the user will not be able to ctrl-c to get
436 back the terminal, effectively hanging the debug session. */
437 fprintf_filtered (gdb_stderr
, _("\
438 Can not resume the parent process over vfork in the foreground while\n\
439 holding the child stopped. Try \"set detach-on-fork\" or \
440 \"set schedule-multiple\".\n"));
441 /* FIXME output string > 80 columns. */
447 /* Detach new forked process? */
450 /* Before detaching from the child, remove all breakpoints
451 from it. If we forked, then this has already been taken
452 care of by infrun.c. If we vforked however, any
453 breakpoint inserted in the parent is visible in the
454 child, even those added while stopped in a vfork
455 catchpoint. This will remove the breakpoints from the
456 parent also, but they'll be reinserted below. */
459 /* Keep breakpoints list in sync. */
460 remove_breakpoints_inf (current_inferior ());
463 if (print_inferior_events
)
465 /* Ensure that we have a process ptid. */
466 ptid_t process_ptid
= ptid_t (child_ptid
.pid ());
468 target_terminal::ours_for_output ();
469 fprintf_filtered (gdb_stdlog
,
470 _("[Detaching after %s from child %s]\n"),
471 has_vforked
? "vfork" : "fork",
472 target_pid_to_str (process_ptid
).c_str ());
477 struct inferior
*parent_inf
, *child_inf
;
479 /* Add process to GDB's tables. */
480 child_inf
= add_inferior (child_ptid
.pid ());
482 parent_inf
= current_inferior ();
483 child_inf
->attach_flag
= parent_inf
->attach_flag
;
484 copy_terminal_info (child_inf
, parent_inf
);
485 child_inf
->gdbarch
= parent_inf
->gdbarch
;
486 copy_inferior_target_desc_info (child_inf
, parent_inf
);
488 scoped_restore_current_pspace_and_thread restore_pspace_thread
;
490 inferior_ptid
= child_ptid
;
491 add_thread_silent (inferior_ptid
);
492 set_current_inferior (child_inf
);
493 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
495 /* If this is a vfork child, then the address-space is
496 shared with the parent. */
499 child_inf
->pspace
= parent_inf
->pspace
;
500 child_inf
->aspace
= parent_inf
->aspace
;
502 /* The parent will be frozen until the child is done
503 with the shared region. Keep track of the
505 child_inf
->vfork_parent
= parent_inf
;
506 child_inf
->pending_detach
= 0;
507 parent_inf
->vfork_child
= child_inf
;
508 parent_inf
->pending_detach
= 0;
512 child_inf
->aspace
= new_address_space ();
513 child_inf
->pspace
= new program_space (child_inf
->aspace
);
514 child_inf
->removable
= 1;
515 set_current_program_space (child_inf
->pspace
);
516 clone_program_space (child_inf
->pspace
, parent_inf
->pspace
);
518 /* Let the shared library layer (e.g., solib-svr4) learn
519 about this new process, relocate the cloned exec, pull
520 in shared libraries, and install the solib event
521 breakpoint. If a "cloned-VM" event was propagated
522 better throughout the core, this wouldn't be
524 solib_create_inferior_hook (0);
530 struct inferior
*parent_inf
;
532 parent_inf
= current_inferior ();
534 /* If we detached from the child, then we have to be careful
535 to not insert breakpoints in the parent until the child
536 is done with the shared memory region. However, if we're
537 staying attached to the child, then we can and should
538 insert breakpoints, so that we can debug it. A
539 subsequent child exec or exit is enough to know when does
540 the child stops using the parent's address space. */
541 parent_inf
->waiting_for_vfork_done
= detach_fork
;
542 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
547 /* Follow the child. */
548 struct inferior
*parent_inf
, *child_inf
;
549 struct program_space
*parent_pspace
;
551 if (print_inferior_events
)
553 std::string parent_pid
= target_pid_to_str (parent_ptid
);
554 std::string child_pid
= target_pid_to_str (child_ptid
);
556 target_terminal::ours_for_output ();
557 fprintf_filtered (gdb_stdlog
,
558 _("[Attaching after %s %s to child %s]\n"),
560 has_vforked
? "vfork" : "fork",
564 /* Add the new inferior first, so that the target_detach below
565 doesn't unpush the target. */
567 child_inf
= add_inferior (child_ptid
.pid ());
569 parent_inf
= current_inferior ();
570 child_inf
->attach_flag
= parent_inf
->attach_flag
;
571 copy_terminal_info (child_inf
, parent_inf
);
572 child_inf
->gdbarch
= parent_inf
->gdbarch
;
573 copy_inferior_target_desc_info (child_inf
, parent_inf
);
575 parent_pspace
= parent_inf
->pspace
;
577 /* If we're vforking, we want to hold on to the parent until the
578 child exits or execs. At child exec or exit time we can
579 remove the old breakpoints from the parent and detach or
580 resume debugging it. Otherwise, detach the parent now; we'll
581 want to reuse it's program/address spaces, but we can't set
582 them to the child before removing breakpoints from the
583 parent, otherwise, the breakpoints module could decide to
584 remove breakpoints from the wrong process (since they'd be
585 assigned to the same address space). */
589 gdb_assert (child_inf
->vfork_parent
== NULL
);
590 gdb_assert (parent_inf
->vfork_child
== NULL
);
591 child_inf
->vfork_parent
= parent_inf
;
592 child_inf
->pending_detach
= 0;
593 parent_inf
->vfork_child
= child_inf
;
594 parent_inf
->pending_detach
= detach_fork
;
595 parent_inf
->waiting_for_vfork_done
= 0;
597 else if (detach_fork
)
599 if (print_inferior_events
)
601 /* Ensure that we have a process ptid. */
602 ptid_t process_ptid
= ptid_t (parent_ptid
.pid ());
604 target_terminal::ours_for_output ();
605 fprintf_filtered (gdb_stdlog
,
606 _("[Detaching after fork from "
608 target_pid_to_str (process_ptid
).c_str ());
611 target_detach (parent_inf
, 0);
614 /* Note that the detach above makes PARENT_INF dangling. */
616 /* Add the child thread to the appropriate lists, and switch to
617 this new thread, before cloning the program space, and
618 informing the solib layer about this new process. */
620 inferior_ptid
= child_ptid
;
621 add_thread_silent (inferior_ptid
);
622 set_current_inferior (child_inf
);
624 /* If this is a vfork child, then the address-space is shared
625 with the parent. If we detached from the parent, then we can
626 reuse the parent's program/address spaces. */
627 if (has_vforked
|| detach_fork
)
629 child_inf
->pspace
= parent_pspace
;
630 child_inf
->aspace
= child_inf
->pspace
->aspace
;
634 child_inf
->aspace
= new_address_space ();
635 child_inf
->pspace
= new program_space (child_inf
->aspace
);
636 child_inf
->removable
= 1;
637 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
638 set_current_program_space (child_inf
->pspace
);
639 clone_program_space (child_inf
->pspace
, parent_pspace
);
641 /* Let the shared library layer (e.g., solib-svr4) learn
642 about this new process, relocate the cloned exec, pull in
643 shared libraries, and install the solib event breakpoint.
644 If a "cloned-VM" event was propagated better throughout
645 the core, this wouldn't be required. */
646 solib_create_inferior_hook (0);
650 return target_follow_fork (follow_child
, detach_fork
);
653 /* Tell the target to follow the fork we're stopped at. Returns true
654 if the inferior should be resumed; false, if the target for some
655 reason decided it's best not to resume. */
660 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
661 int should_resume
= 1;
662 struct thread_info
*tp
;
664 /* Copy user stepping state to the new inferior thread. FIXME: the
665 followed fork child thread should have a copy of most of the
666 parent thread structure's run control related fields, not just these.
667 Initialized to avoid "may be used uninitialized" warnings from gcc. */
668 struct breakpoint
*step_resume_breakpoint
= NULL
;
669 struct breakpoint
*exception_resume_breakpoint
= NULL
;
670 CORE_ADDR step_range_start
= 0;
671 CORE_ADDR step_range_end
= 0;
672 struct frame_id step_frame_id
= { 0 };
673 struct thread_fsm
*thread_fsm
= NULL
;
678 struct target_waitstatus wait_status
;
680 /* Get the last target status returned by target_wait(). */
681 get_last_target_status (&wait_ptid
, &wait_status
);
683 /* If not stopped at a fork event, then there's nothing else to
685 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
686 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
689 /* Check if we switched over from WAIT_PTID, since the event was
691 if (wait_ptid
!= minus_one_ptid
692 && inferior_ptid
!= wait_ptid
)
694 /* We did. Switch back to WAIT_PTID thread, to tell the
695 target to follow it (in either direction). We'll
696 afterwards refuse to resume, and inform the user what
698 thread_info
*wait_thread
699 = find_thread_ptid (wait_ptid
);
700 switch_to_thread (wait_thread
);
705 tp
= inferior_thread ();
707 /* If there were any forks/vforks that were caught and are now to be
708 followed, then do so now. */
709 switch (tp
->pending_follow
.kind
)
711 case TARGET_WAITKIND_FORKED
:
712 case TARGET_WAITKIND_VFORKED
:
714 ptid_t parent
, child
;
716 /* If the user did a next/step, etc, over a fork call,
717 preserve the stepping state in the fork child. */
718 if (follow_child
&& should_resume
)
720 step_resume_breakpoint
= clone_momentary_breakpoint
721 (tp
->control
.step_resume_breakpoint
);
722 step_range_start
= tp
->control
.step_range_start
;
723 step_range_end
= tp
->control
.step_range_end
;
724 step_frame_id
= tp
->control
.step_frame_id
;
725 exception_resume_breakpoint
726 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
727 thread_fsm
= tp
->thread_fsm
;
729 /* For now, delete the parent's sr breakpoint, otherwise,
730 parent/child sr breakpoints are considered duplicates,
731 and the child version will not be installed. Remove
732 this when the breakpoints module becomes aware of
733 inferiors and address spaces. */
734 delete_step_resume_breakpoint (tp
);
735 tp
->control
.step_range_start
= 0;
736 tp
->control
.step_range_end
= 0;
737 tp
->control
.step_frame_id
= null_frame_id
;
738 delete_exception_resume_breakpoint (tp
);
739 tp
->thread_fsm
= NULL
;
742 parent
= inferior_ptid
;
743 child
= tp
->pending_follow
.value
.related_pid
;
745 /* Set up inferior(s) as specified by the caller, and tell the
746 target to do whatever is necessary to follow either parent
748 if (follow_fork_inferior (follow_child
, detach_fork
))
750 /* Target refused to follow, or there's some other reason
751 we shouldn't resume. */
756 /* This pending follow fork event is now handled, one way
757 or another. The previous selected thread may be gone
758 from the lists by now, but if it is still around, need
759 to clear the pending follow request. */
760 tp
= find_thread_ptid (parent
);
762 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
764 /* This makes sure we don't try to apply the "Switched
765 over from WAIT_PID" logic above. */
766 nullify_last_target_wait_ptid ();
768 /* If we followed the child, switch to it... */
771 thread_info
*child_thr
= find_thread_ptid (child
);
772 switch_to_thread (child_thr
);
774 /* ... and preserve the stepping state, in case the
775 user was stepping over the fork call. */
778 tp
= inferior_thread ();
779 tp
->control
.step_resume_breakpoint
780 = step_resume_breakpoint
;
781 tp
->control
.step_range_start
= step_range_start
;
782 tp
->control
.step_range_end
= step_range_end
;
783 tp
->control
.step_frame_id
= step_frame_id
;
784 tp
->control
.exception_resume_breakpoint
785 = exception_resume_breakpoint
;
786 tp
->thread_fsm
= thread_fsm
;
790 /* If we get here, it was because we're trying to
791 resume from a fork catchpoint, but, the user
792 has switched threads away from the thread that
793 forked. In that case, the resume command
794 issued is most likely not applicable to the
795 child, so just warn, and refuse to resume. */
796 warning (_("Not resuming: switched threads "
797 "before following fork child."));
800 /* Reset breakpoints in the child as appropriate. */
801 follow_inferior_reset_breakpoints ();
806 case TARGET_WAITKIND_SPURIOUS
:
807 /* Nothing to follow. */
810 internal_error (__FILE__
, __LINE__
,
811 "Unexpected pending_follow.kind %d\n",
812 tp
->pending_follow
.kind
);
816 return should_resume
;
820 follow_inferior_reset_breakpoints (void)
822 struct thread_info
*tp
= inferior_thread ();
824 /* Was there a step_resume breakpoint? (There was if the user
825 did a "next" at the fork() call.) If so, explicitly reset its
826 thread number. Cloned step_resume breakpoints are disabled on
827 creation, so enable it here now that it is associated with the
830 step_resumes are a form of bp that are made to be per-thread.
831 Since we created the step_resume bp when the parent process
832 was being debugged, and now are switching to the child process,
833 from the breakpoint package's viewpoint, that's a switch of
834 "threads". We must update the bp's notion of which thread
835 it is for, or it'll be ignored when it triggers. */
837 if (tp
->control
.step_resume_breakpoint
)
839 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
840 tp
->control
.step_resume_breakpoint
->loc
->enabled
= 1;
843 /* Treat exception_resume breakpoints like step_resume breakpoints. */
844 if (tp
->control
.exception_resume_breakpoint
)
846 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
847 tp
->control
.exception_resume_breakpoint
->loc
->enabled
= 1;
850 /* Reinsert all breakpoints in the child. The user may have set
851 breakpoints after catching the fork, in which case those
852 were never set in the child, but only in the parent. This makes
853 sure the inserted breakpoints match the breakpoint list. */
855 breakpoint_re_set ();
856 insert_breakpoints ();
859 /* The child has exited or execed: resume threads of the parent the
860 user wanted to be executing. */
863 proceed_after_vfork_done (struct thread_info
*thread
,
866 int pid
= * (int *) arg
;
868 if (thread
->ptid
.pid () == pid
869 && thread
->state
== THREAD_RUNNING
870 && !thread
->executing
871 && !thread
->stop_requested
872 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
875 fprintf_unfiltered (gdb_stdlog
,
876 "infrun: resuming vfork parent thread %s\n",
877 target_pid_to_str (thread
->ptid
).c_str ());
879 switch_to_thread (thread
);
880 clear_proceed_status (0);
881 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
);
887 /* Save/restore inferior_ptid, current program space and current
888 inferior. Only use this if the current context points at an exited
889 inferior (and therefore there's no current thread to save). */
890 class scoped_restore_exited_inferior
893 scoped_restore_exited_inferior ()
894 : m_saved_ptid (&inferior_ptid
)
898 scoped_restore_tmpl
<ptid_t
> m_saved_ptid
;
899 scoped_restore_current_program_space m_pspace
;
900 scoped_restore_current_inferior m_inferior
;
903 /* Called whenever we notice an exec or exit event, to handle
904 detaching or resuming a vfork parent. */
907 handle_vfork_child_exec_or_exit (int exec
)
909 struct inferior
*inf
= current_inferior ();
911 if (inf
->vfork_parent
)
913 int resume_parent
= -1;
915 /* This exec or exit marks the end of the shared memory region
916 between the parent and the child. Break the bonds. */
917 inferior
*vfork_parent
= inf
->vfork_parent
;
918 inf
->vfork_parent
->vfork_child
= NULL
;
919 inf
->vfork_parent
= NULL
;
921 /* If the user wanted to detach from the parent, now is the
923 if (vfork_parent
->pending_detach
)
925 struct thread_info
*tp
;
926 struct program_space
*pspace
;
927 struct address_space
*aspace
;
929 /* follow-fork child, detach-on-fork on. */
931 vfork_parent
->pending_detach
= 0;
933 gdb::optional
<scoped_restore_exited_inferior
>
934 maybe_restore_inferior
;
935 gdb::optional
<scoped_restore_current_pspace_and_thread
>
936 maybe_restore_thread
;
938 /* If we're handling a child exit, then inferior_ptid points
939 at the inferior's pid, not to a thread. */
941 maybe_restore_inferior
.emplace ();
943 maybe_restore_thread
.emplace ();
945 /* We're letting loose of the parent. */
946 tp
= any_live_thread_of_inferior (vfork_parent
);
947 switch_to_thread (tp
);
949 /* We're about to detach from the parent, which implicitly
950 removes breakpoints from its address space. There's a
951 catch here: we want to reuse the spaces for the child,
952 but, parent/child are still sharing the pspace at this
953 point, although the exec in reality makes the kernel give
954 the child a fresh set of new pages. The problem here is
955 that the breakpoints module being unaware of this, would
956 likely chose the child process to write to the parent
957 address space. Swapping the child temporarily away from
958 the spaces has the desired effect. Yes, this is "sort
961 pspace
= inf
->pspace
;
962 aspace
= inf
->aspace
;
966 if (print_inferior_events
)
969 = target_pid_to_str (ptid_t (vfork_parent
->pid
));
971 target_terminal::ours_for_output ();
975 fprintf_filtered (gdb_stdlog
,
976 _("[Detaching vfork parent %s "
977 "after child exec]\n"), pidstr
.c_str ());
981 fprintf_filtered (gdb_stdlog
,
982 _("[Detaching vfork parent %s "
983 "after child exit]\n"), pidstr
.c_str ());
987 target_detach (vfork_parent
, 0);
990 inf
->pspace
= pspace
;
991 inf
->aspace
= aspace
;
995 /* We're staying attached to the parent, so, really give the
996 child a new address space. */
997 inf
->pspace
= new program_space (maybe_new_address_space ());
998 inf
->aspace
= inf
->pspace
->aspace
;
1000 set_current_program_space (inf
->pspace
);
1002 resume_parent
= vfork_parent
->pid
;
1006 struct program_space
*pspace
;
1008 /* If this is a vfork child exiting, then the pspace and
1009 aspaces were shared with the parent. Since we're
1010 reporting the process exit, we'll be mourning all that is
1011 found in the address space, and switching to null_ptid,
1012 preparing to start a new inferior. But, since we don't
1013 want to clobber the parent's address/program spaces, we
1014 go ahead and create a new one for this exiting
1017 /* Switch to null_ptid while running clone_program_space, so
1018 that clone_program_space doesn't want to read the
1019 selected frame of a dead process. */
1020 scoped_restore restore_ptid
1021 = make_scoped_restore (&inferior_ptid
, null_ptid
);
1023 /* This inferior is dead, so avoid giving the breakpoints
1024 module the option to write through to it (cloning a
1025 program space resets breakpoints). */
1028 pspace
= new program_space (maybe_new_address_space ());
1029 set_current_program_space (pspace
);
1031 inf
->symfile_flags
= SYMFILE_NO_READ
;
1032 clone_program_space (pspace
, vfork_parent
->pspace
);
1033 inf
->pspace
= pspace
;
1034 inf
->aspace
= pspace
->aspace
;
1036 resume_parent
= vfork_parent
->pid
;
1039 gdb_assert (current_program_space
== inf
->pspace
);
1041 if (non_stop
&& resume_parent
!= -1)
1043 /* If the user wanted the parent to be running, let it go
1045 scoped_restore_current_thread restore_thread
;
1048 fprintf_unfiltered (gdb_stdlog
,
1049 "infrun: resuming vfork parent process %d\n",
1052 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
1057 /* Enum strings for "set|show follow-exec-mode". */
1059 static const char follow_exec_mode_new
[] = "new";
1060 static const char follow_exec_mode_same
[] = "same";
1061 static const char *const follow_exec_mode_names
[] =
1063 follow_exec_mode_new
,
1064 follow_exec_mode_same
,
1068 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1070 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1071 struct cmd_list_element
*c
, const char *value
)
1073 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1076 /* EXEC_FILE_TARGET is assumed to be non-NULL. */
1079 follow_exec (ptid_t ptid
, const char *exec_file_target
)
1081 struct inferior
*inf
= current_inferior ();
1082 int pid
= ptid
.pid ();
1083 ptid_t process_ptid
;
1085 /* Switch terminal for any messages produced e.g. by
1086 breakpoint_re_set. */
1087 target_terminal::ours_for_output ();
1089 /* This is an exec event that we actually wish to pay attention to.
1090 Refresh our symbol table to the newly exec'd program, remove any
1091 momentary bp's, etc.
1093 If there are breakpoints, they aren't really inserted now,
1094 since the exec() transformed our inferior into a fresh set
1097 We want to preserve symbolic breakpoints on the list, since
1098 we have hopes that they can be reset after the new a.out's
1099 symbol table is read.
1101 However, any "raw" breakpoints must be removed from the list
1102 (e.g., the solib bp's), since their address is probably invalid
1105 And, we DON'T want to call delete_breakpoints() here, since
1106 that may write the bp's "shadow contents" (the instruction
1107 value that was overwritten with a TRAP instruction). Since
1108 we now have a new a.out, those shadow contents aren't valid. */
1110 mark_breakpoints_out ();
1112 /* The target reports the exec event to the main thread, even if
1113 some other thread does the exec, and even if the main thread was
1114 stopped or already gone. We may still have non-leader threads of
1115 the process on our list. E.g., on targets that don't have thread
1116 exit events (like remote); or on native Linux in non-stop mode if
1117 there were only two threads in the inferior and the non-leader
1118 one is the one that execs (and nothing forces an update of the
1119 thread list up to here). When debugging remotely, it's best to
1120 avoid extra traffic, when possible, so avoid syncing the thread
1121 list with the target, and instead go ahead and delete all threads
1122 of the process but one that reported the event. Note this must
1123 be done before calling update_breakpoints_after_exec, as
1124 otherwise clearing the threads' resources would reference stale
1125 thread breakpoints -- it may have been one of these threads that
1126 stepped across the exec. We could just clear their stepping
1127 states, but as long as we're iterating, might as well delete
1128 them. Deleting them now rather than at the next user-visible
1129 stop provides a nicer sequence of events for user and MI
1131 for (thread_info
*th
: all_threads_safe ())
1132 if (th
->ptid
.pid () == pid
&& th
->ptid
!= ptid
)
1135 /* We also need to clear any left over stale state for the
1136 leader/event thread. E.g., if there was any step-resume
1137 breakpoint or similar, it's gone now. We cannot truly
1138 step-to-next statement through an exec(). */
1139 thread_info
*th
= inferior_thread ();
1140 th
->control
.step_resume_breakpoint
= NULL
;
1141 th
->control
.exception_resume_breakpoint
= NULL
;
1142 th
->control
.single_step_breakpoints
= NULL
;
1143 th
->control
.step_range_start
= 0;
1144 th
->control
.step_range_end
= 0;
1146 /* The user may have had the main thread held stopped in the
1147 previous image (e.g., schedlock on, or non-stop). Release
1149 th
->stop_requested
= 0;
1151 update_breakpoints_after_exec ();
1153 /* What is this a.out's name? */
1154 process_ptid
= ptid_t (pid
);
1155 printf_unfiltered (_("%s is executing new program: %s\n"),
1156 target_pid_to_str (process_ptid
).c_str (),
1159 /* We've followed the inferior through an exec. Therefore, the
1160 inferior has essentially been killed & reborn. */
1162 breakpoint_init_inferior (inf_execd
);
1164 gdb::unique_xmalloc_ptr
<char> exec_file_host
1165 = exec_file_find (exec_file_target
, NULL
);
1167 /* If we were unable to map the executable target pathname onto a host
1168 pathname, tell the user that. Otherwise GDB's subsequent behavior
1169 is confusing. Maybe it would even be better to stop at this point
1170 so that the user can specify a file manually before continuing. */
1171 if (exec_file_host
== NULL
)
1172 warning (_("Could not load symbols for executable %s.\n"
1173 "Do you need \"set sysroot\"?"),
1176 /* Reset the shared library package. This ensures that we get a
1177 shlib event when the child reaches "_start", at which point the
1178 dld will have had a chance to initialize the child. */
1179 /* Also, loading a symbol file below may trigger symbol lookups, and
1180 we don't want those to be satisfied by the libraries of the
1181 previous incarnation of this process. */
1182 no_shared_libraries (NULL
, 0);
1184 if (follow_exec_mode_string
== follow_exec_mode_new
)
1186 /* The user wants to keep the old inferior and program spaces
1187 around. Create a new fresh one, and switch to it. */
1189 /* Do exit processing for the original inferior before setting the new
1190 inferior's pid. Having two inferiors with the same pid would confuse
1191 find_inferior_p(t)id. Transfer the terminal state and info from the
1192 old to the new inferior. */
1193 inf
= add_inferior_with_spaces ();
1194 swap_terminal_info (inf
, current_inferior ());
1195 exit_inferior_silent (current_inferior ());
1198 target_follow_exec (inf
, exec_file_target
);
1200 set_current_inferior (inf
);
1201 set_current_program_space (inf
->pspace
);
1206 /* The old description may no longer be fit for the new image.
1207 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1208 old description; we'll read a new one below. No need to do
1209 this on "follow-exec-mode new", as the old inferior stays
1210 around (its description is later cleared/refetched on
1212 target_clear_description ();
1215 gdb_assert (current_program_space
== inf
->pspace
);
1217 /* Attempt to open the exec file. SYMFILE_DEFER_BP_RESET is used
1218 because the proper displacement for a PIE (Position Independent
1219 Executable) main symbol file will only be computed by
1220 solib_create_inferior_hook below. breakpoint_re_set would fail
1221 to insert the breakpoints with the zero displacement. */
1222 try_open_exec_file (exec_file_host
.get (), inf
, SYMFILE_DEFER_BP_RESET
);
1224 /* If the target can specify a description, read it. Must do this
1225 after flipping to the new executable (because the target supplied
1226 description must be compatible with the executable's
1227 architecture, and the old executable may e.g., be 32-bit, while
1228 the new one 64-bit), and before anything involving memory or
1230 target_find_description ();
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 successfully 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 /* Get the displaced stepping state of process PID. */
1479 static displaced_step_inferior_state
*
1480 get_displaced_stepping_state (inferior
*inf
)
1482 return &inf
->displaced_step_state
;
1485 /* Returns true if any inferior has a thread doing a displaced
1489 displaced_step_in_progress_any_inferior ()
1491 for (inferior
*i
: all_inferiors ())
1493 if (i
->displaced_step_state
.step_thread
!= nullptr)
1500 /* Return true if thread represented by PTID is doing a displaced
1504 displaced_step_in_progress_thread (thread_info
*thread
)
1506 gdb_assert (thread
!= NULL
);
1508 return get_displaced_stepping_state (thread
->inf
)->step_thread
== thread
;
1511 /* Return true if process PID has a thread doing a displaced step. */
1514 displaced_step_in_progress (inferior
*inf
)
1516 return get_displaced_stepping_state (inf
)->step_thread
!= nullptr;
1519 /* If inferior is in displaced stepping, and ADDR equals to starting address
1520 of copy area, return corresponding displaced_step_closure. Otherwise,
1523 struct displaced_step_closure
*
1524 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1526 displaced_step_inferior_state
*displaced
1527 = get_displaced_stepping_state (current_inferior ());
1529 /* If checking the mode of displaced instruction in copy area. */
1530 if (displaced
->step_thread
!= nullptr
1531 && displaced
->step_copy
== addr
)
1532 return displaced
->step_closure
;
1538 infrun_inferior_exit (struct inferior
*inf
)
1540 inf
->displaced_step_state
.reset ();
1543 /* If ON, and the architecture supports it, GDB will use displaced
1544 stepping to step over breakpoints. If OFF, or if the architecture
1545 doesn't support it, GDB will instead use the traditional
1546 hold-and-step approach. If AUTO (which is the default), GDB will
1547 decide which technique to use to step over breakpoints depending on
1548 which of all-stop or non-stop mode is active --- displaced stepping
1549 in non-stop mode; hold-and-step in all-stop mode. */
1551 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1554 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1555 struct cmd_list_element
*c
,
1558 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1559 fprintf_filtered (file
,
1560 _("Debugger's willingness to use displaced stepping "
1561 "to step over breakpoints is %s (currently %s).\n"),
1562 value
, target_is_non_stop_p () ? "on" : "off");
1564 fprintf_filtered (file
,
1565 _("Debugger's willingness to use displaced stepping "
1566 "to step over breakpoints is %s.\n"), value
);
1569 /* Return non-zero if displaced stepping can/should be used to step
1570 over breakpoints of thread TP. */
1573 use_displaced_stepping (struct thread_info
*tp
)
1575 struct regcache
*regcache
= get_thread_regcache (tp
);
1576 struct gdbarch
*gdbarch
= regcache
->arch ();
1577 displaced_step_inferior_state
*displaced_state
1578 = get_displaced_stepping_state (tp
->inf
);
1580 return (((can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
1581 && target_is_non_stop_p ())
1582 || can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1583 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1584 && find_record_target () == NULL
1585 && !displaced_state
->failed_before
);
1588 /* Clean out any stray displaced stepping state. */
1590 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1592 /* Indicate that there is no cleanup pending. */
1593 displaced
->step_thread
= nullptr;
1595 delete displaced
->step_closure
;
1596 displaced
->step_closure
= NULL
;
1599 /* A cleanup that wraps displaced_step_clear. */
1600 using displaced_step_clear_cleanup
1601 = FORWARD_SCOPE_EXIT (displaced_step_clear
);
1603 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1605 displaced_step_dump_bytes (struct ui_file
*file
,
1606 const gdb_byte
*buf
,
1611 for (i
= 0; i
< len
; i
++)
1612 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1613 fputs_unfiltered ("\n", file
);
1616 /* Prepare to single-step, using displaced stepping.
1618 Note that we cannot use displaced stepping when we have a signal to
1619 deliver. If we have a signal to deliver and an instruction to step
1620 over, then after the step, there will be no indication from the
1621 target whether the thread entered a signal handler or ignored the
1622 signal and stepped over the instruction successfully --- both cases
1623 result in a simple SIGTRAP. In the first case we mustn't do a
1624 fixup, and in the second case we must --- but we can't tell which.
1625 Comments in the code for 'random signals' in handle_inferior_event
1626 explain how we handle this case instead.
1628 Returns 1 if preparing was successful -- this thread is going to be
1629 stepped now; 0 if displaced stepping this thread got queued; or -1
1630 if this instruction can't be displaced stepped. */
1633 displaced_step_prepare_throw (thread_info
*tp
)
1635 regcache
*regcache
= get_thread_regcache (tp
);
1636 struct gdbarch
*gdbarch
= regcache
->arch ();
1637 const address_space
*aspace
= regcache
->aspace ();
1638 CORE_ADDR original
, copy
;
1640 struct displaced_step_closure
*closure
;
1643 /* We should never reach this function if the architecture does not
1644 support displaced stepping. */
1645 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1647 /* Nor if the thread isn't meant to step over a breakpoint. */
1648 gdb_assert (tp
->control
.trap_expected
);
1650 /* Disable range stepping while executing in the scratch pad. We
1651 want a single-step even if executing the displaced instruction in
1652 the scratch buffer lands within the stepping range (e.g., a
1654 tp
->control
.may_range_step
= 0;
1656 /* We have to displaced step one thread at a time, as we only have
1657 access to a single scratch space per inferior. */
1659 displaced_step_inferior_state
*displaced
1660 = get_displaced_stepping_state (tp
->inf
);
1662 if (displaced
->step_thread
!= nullptr)
1664 /* Already waiting for a displaced step to finish. Defer this
1665 request and place in queue. */
1667 if (debug_displaced
)
1668 fprintf_unfiltered (gdb_stdlog
,
1669 "displaced: deferring step of %s\n",
1670 target_pid_to_str (tp
->ptid
).c_str ());
1672 thread_step_over_chain_enqueue (tp
);
1677 if (debug_displaced
)
1678 fprintf_unfiltered (gdb_stdlog
,
1679 "displaced: stepping %s now\n",
1680 target_pid_to_str (tp
->ptid
).c_str ());
1683 displaced_step_clear (displaced
);
1685 scoped_restore_current_thread restore_thread
;
1687 switch_to_thread (tp
);
1689 original
= regcache_read_pc (regcache
);
1691 copy
= gdbarch_displaced_step_location (gdbarch
);
1692 len
= gdbarch_max_insn_length (gdbarch
);
1694 if (breakpoint_in_range_p (aspace
, copy
, len
))
1696 /* There's a breakpoint set in the scratch pad location range
1697 (which is usually around the entry point). We'd either
1698 install it before resuming, which would overwrite/corrupt the
1699 scratch pad, or if it was already inserted, this displaced
1700 step would overwrite it. The latter is OK in the sense that
1701 we already assume that no thread is going to execute the code
1702 in the scratch pad range (after initial startup) anyway, but
1703 the former is unacceptable. Simply punt and fallback to
1704 stepping over this breakpoint in-line. */
1705 if (debug_displaced
)
1707 fprintf_unfiltered (gdb_stdlog
,
1708 "displaced: breakpoint set in scratch pad. "
1709 "Stepping over breakpoint in-line instead.\n");
1715 /* Save the original contents of the copy area. */
1716 displaced
->step_saved_copy
.resize (len
);
1717 status
= target_read_memory (copy
, displaced
->step_saved_copy
.data (), len
);
1719 throw_error (MEMORY_ERROR
,
1720 _("Error accessing memory address %s (%s) for "
1721 "displaced-stepping scratch space."),
1722 paddress (gdbarch
, copy
), safe_strerror (status
));
1723 if (debug_displaced
)
1725 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1726 paddress (gdbarch
, copy
));
1727 displaced_step_dump_bytes (gdb_stdlog
,
1728 displaced
->step_saved_copy
.data (),
1732 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1733 original
, copy
, regcache
);
1734 if (closure
== NULL
)
1736 /* The architecture doesn't know how or want to displaced step
1737 this instruction or instruction sequence. Fallback to
1738 stepping over the breakpoint in-line. */
1742 /* Save the information we need to fix things up if the step
1744 displaced
->step_thread
= tp
;
1745 displaced
->step_gdbarch
= gdbarch
;
1746 displaced
->step_closure
= closure
;
1747 displaced
->step_original
= original
;
1748 displaced
->step_copy
= copy
;
1751 displaced_step_clear_cleanup
cleanup (displaced
);
1753 /* Resume execution at the copy. */
1754 regcache_write_pc (regcache
, copy
);
1759 if (debug_displaced
)
1760 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1761 paddress (gdbarch
, copy
));
1766 /* Wrapper for displaced_step_prepare_throw that disabled further
1767 attempts at displaced stepping if we get a memory error. */
1770 displaced_step_prepare (thread_info
*thread
)
1776 prepared
= displaced_step_prepare_throw (thread
);
1778 catch (const gdb_exception_error
&ex
)
1780 struct displaced_step_inferior_state
*displaced_state
;
1782 if (ex
.error
!= MEMORY_ERROR
1783 && ex
.error
!= NOT_SUPPORTED_ERROR
)
1788 fprintf_unfiltered (gdb_stdlog
,
1789 "infrun: disabling displaced stepping: %s\n",
1793 /* Be verbose if "set displaced-stepping" is "on", silent if
1795 if (can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1797 warning (_("disabling displaced stepping: %s"),
1801 /* Disable further displaced stepping attempts. */
1803 = get_displaced_stepping_state (thread
->inf
);
1804 displaced_state
->failed_before
= 1;
1811 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1812 const gdb_byte
*myaddr
, int len
)
1814 scoped_restore save_inferior_ptid
= make_scoped_restore (&inferior_ptid
);
1816 inferior_ptid
= ptid
;
1817 write_memory (memaddr
, myaddr
, len
);
1820 /* Restore the contents of the copy area for thread PTID. */
1823 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1826 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1828 write_memory_ptid (ptid
, displaced
->step_copy
,
1829 displaced
->step_saved_copy
.data (), len
);
1830 if (debug_displaced
)
1831 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1832 target_pid_to_str (ptid
).c_str (),
1833 paddress (displaced
->step_gdbarch
,
1834 displaced
->step_copy
));
1837 /* If we displaced stepped an instruction successfully, adjust
1838 registers and memory to yield the same effect the instruction would
1839 have had if we had executed it at its original address, and return
1840 1. If the instruction didn't complete, relocate the PC and return
1841 -1. If the thread wasn't displaced stepping, return 0. */
1844 displaced_step_fixup (thread_info
*event_thread
, enum gdb_signal signal
)
1846 struct displaced_step_inferior_state
*displaced
1847 = get_displaced_stepping_state (event_thread
->inf
);
1850 /* Was this event for the thread we displaced? */
1851 if (displaced
->step_thread
!= event_thread
)
1854 displaced_step_clear_cleanup
cleanup (displaced
);
1856 displaced_step_restore (displaced
, displaced
->step_thread
->ptid
);
1858 /* Fixup may need to read memory/registers. Switch to the thread
1859 that we're fixing up. Also, target_stopped_by_watchpoint checks
1860 the current thread. */
1861 switch_to_thread (event_thread
);
1863 /* Did the instruction complete successfully? */
1864 if (signal
== GDB_SIGNAL_TRAP
1865 && !(target_stopped_by_watchpoint ()
1866 && (gdbarch_have_nonsteppable_watchpoint (displaced
->step_gdbarch
)
1867 || target_have_steppable_watchpoint
)))
1869 /* Fix up the resulting state. */
1870 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
1871 displaced
->step_closure
,
1872 displaced
->step_original
,
1873 displaced
->step_copy
,
1874 get_thread_regcache (displaced
->step_thread
));
1879 /* Since the instruction didn't complete, all we can do is
1881 struct regcache
*regcache
= get_thread_regcache (event_thread
);
1882 CORE_ADDR pc
= regcache_read_pc (regcache
);
1884 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
1885 regcache_write_pc (regcache
, pc
);
1892 /* Data to be passed around while handling an event. This data is
1893 discarded between events. */
1894 struct execution_control_state
1897 /* The thread that got the event, if this was a thread event; NULL
1899 struct thread_info
*event_thread
;
1901 struct target_waitstatus ws
;
1902 int stop_func_filled_in
;
1903 CORE_ADDR stop_func_start
;
1904 CORE_ADDR stop_func_end
;
1905 const char *stop_func_name
;
1908 /* True if the event thread hit the single-step breakpoint of
1909 another thread. Thus the event doesn't cause a stop, the thread
1910 needs to be single-stepped past the single-step breakpoint before
1911 we can switch back to the original stepping thread. */
1912 int hit_singlestep_breakpoint
;
1915 /* Clear ECS and set it to point at TP. */
1918 reset_ecs (struct execution_control_state
*ecs
, struct thread_info
*tp
)
1920 memset (ecs
, 0, sizeof (*ecs
));
1921 ecs
->event_thread
= tp
;
1922 ecs
->ptid
= tp
->ptid
;
1925 static void keep_going_pass_signal (struct execution_control_state
*ecs
);
1926 static void prepare_to_wait (struct execution_control_state
*ecs
);
1927 static int keep_going_stepped_thread (struct thread_info
*tp
);
1928 static step_over_what
thread_still_needs_step_over (struct thread_info
*tp
);
1930 /* Are there any pending step-over requests? If so, run all we can
1931 now and return true. Otherwise, return false. */
1934 start_step_over (void)
1936 struct thread_info
*tp
, *next
;
1938 /* Don't start a new step-over if we already have an in-line
1939 step-over operation ongoing. */
1940 if (step_over_info_valid_p ())
1943 for (tp
= step_over_queue_head
; tp
!= NULL
; tp
= next
)
1945 struct execution_control_state ecss
;
1946 struct execution_control_state
*ecs
= &ecss
;
1947 step_over_what step_what
;
1948 int must_be_in_line
;
1950 gdb_assert (!tp
->stop_requested
);
1952 next
= thread_step_over_chain_next (tp
);
1954 /* If this inferior already has a displaced step in process,
1955 don't start a new one. */
1956 if (displaced_step_in_progress (tp
->inf
))
1959 step_what
= thread_still_needs_step_over (tp
);
1960 must_be_in_line
= ((step_what
& STEP_OVER_WATCHPOINT
)
1961 || ((step_what
& STEP_OVER_BREAKPOINT
)
1962 && !use_displaced_stepping (tp
)));
1964 /* We currently stop all threads of all processes to step-over
1965 in-line. If we need to start a new in-line step-over, let
1966 any pending displaced steps finish first. */
1967 if (must_be_in_line
&& displaced_step_in_progress_any_inferior ())
1970 thread_step_over_chain_remove (tp
);
1972 if (step_over_queue_head
== NULL
)
1975 fprintf_unfiltered (gdb_stdlog
,
1976 "infrun: step-over queue now empty\n");
1979 if (tp
->control
.trap_expected
1983 internal_error (__FILE__
, __LINE__
,
1984 "[%s] has inconsistent state: "
1985 "trap_expected=%d, resumed=%d, executing=%d\n",
1986 target_pid_to_str (tp
->ptid
).c_str (),
1987 tp
->control
.trap_expected
,
1993 fprintf_unfiltered (gdb_stdlog
,
1994 "infrun: resuming [%s] for step-over\n",
1995 target_pid_to_str (tp
->ptid
).c_str ());
1997 /* keep_going_pass_signal skips the step-over if the breakpoint
1998 is no longer inserted. In all-stop, we want to keep looking
1999 for a thread that needs a step-over instead of resuming TP,
2000 because we wouldn't be able to resume anything else until the
2001 target stops again. In non-stop, the resume always resumes
2002 only TP, so it's OK to let the thread resume freely. */
2003 if (!target_is_non_stop_p () && !step_what
)
2006 switch_to_thread (tp
);
2007 reset_ecs (ecs
, tp
);
2008 keep_going_pass_signal (ecs
);
2010 if (!ecs
->wait_some_more
)
2011 error (_("Command aborted."));
2013 gdb_assert (tp
->resumed
);
2015 /* If we started a new in-line step-over, we're done. */
2016 if (step_over_info_valid_p ())
2018 gdb_assert (tp
->control
.trap_expected
);
2022 if (!target_is_non_stop_p ())
2024 /* On all-stop, shouldn't have resumed unless we needed a
2026 gdb_assert (tp
->control
.trap_expected
2027 || tp
->step_after_step_resume_breakpoint
);
2029 /* With remote targets (at least), in all-stop, we can't
2030 issue any further remote commands until the program stops
2035 /* Either the thread no longer needed a step-over, or a new
2036 displaced stepping sequence started. Even in the latter
2037 case, continue looking. Maybe we can also start another
2038 displaced step on a thread of other process. */
2044 /* Update global variables holding ptids to hold NEW_PTID if they were
2045 holding OLD_PTID. */
2047 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
2049 if (inferior_ptid
== old_ptid
)
2050 inferior_ptid
= new_ptid
;
2055 static const char schedlock_off
[] = "off";
2056 static const char schedlock_on
[] = "on";
2057 static const char schedlock_step
[] = "step";
2058 static const char schedlock_replay
[] = "replay";
2059 static const char *const scheduler_enums
[] = {
2066 static const char *scheduler_mode
= schedlock_replay
;
2068 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
2069 struct cmd_list_element
*c
, const char *value
)
2071 fprintf_filtered (file
,
2072 _("Mode for locking scheduler "
2073 "during execution is \"%s\".\n"),
2078 set_schedlock_func (const char *args
, int from_tty
, struct cmd_list_element
*c
)
2080 if (!target_can_lock_scheduler
)
2082 scheduler_mode
= schedlock_off
;
2083 error (_("Target '%s' cannot support this command."), target_shortname
);
2087 /* True if execution commands resume all threads of all processes by
2088 default; otherwise, resume only threads of the current inferior
2090 bool sched_multi
= false;
2092 /* Try to setup for software single stepping over the specified location.
2093 Return 1 if target_resume() should use hardware single step.
2095 GDBARCH the current gdbarch.
2096 PC the location to step over. */
2099 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
2103 if (execution_direction
== EXEC_FORWARD
2104 && gdbarch_software_single_step_p (gdbarch
))
2105 hw_step
= !insert_single_step_breakpoints (gdbarch
);
2113 user_visible_resume_ptid (int step
)
2119 /* With non-stop mode on, threads are always handled
2121 resume_ptid
= inferior_ptid
;
2123 else if ((scheduler_mode
== schedlock_on
)
2124 || (scheduler_mode
== schedlock_step
&& step
))
2126 /* User-settable 'scheduler' mode requires solo thread
2128 resume_ptid
= inferior_ptid
;
2130 else if ((scheduler_mode
== schedlock_replay
)
2131 && target_record_will_replay (minus_one_ptid
, execution_direction
))
2133 /* User-settable 'scheduler' mode requires solo thread resume in replay
2135 resume_ptid
= inferior_ptid
;
2137 else if (!sched_multi
&& target_supports_multi_process ())
2139 /* Resume all threads of the current process (and none of other
2141 resume_ptid
= ptid_t (inferior_ptid
.pid ());
2145 /* Resume all threads of all processes. */
2146 resume_ptid
= RESUME_ALL
;
2152 /* Return a ptid representing the set of threads that we will resume,
2153 in the perspective of the target, assuming run control handling
2154 does not require leaving some threads stopped (e.g., stepping past
2155 breakpoint). USER_STEP indicates whether we're about to start the
2156 target for a stepping command. */
2159 internal_resume_ptid (int user_step
)
2161 /* In non-stop, we always control threads individually. Note that
2162 the target may always work in non-stop mode even with "set
2163 non-stop off", in which case user_visible_resume_ptid could
2164 return a wildcard ptid. */
2165 if (target_is_non_stop_p ())
2166 return inferior_ptid
;
2168 return user_visible_resume_ptid (user_step
);
2171 /* Wrapper for target_resume, that handles infrun-specific
2175 do_target_resume (ptid_t resume_ptid
, int step
, enum gdb_signal sig
)
2177 struct thread_info
*tp
= inferior_thread ();
2179 gdb_assert (!tp
->stop_requested
);
2181 /* Install inferior's terminal modes. */
2182 target_terminal::inferior ();
2184 /* Avoid confusing the next resume, if the next stop/resume
2185 happens to apply to another thread. */
2186 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2188 /* Advise target which signals may be handled silently.
2190 If we have removed breakpoints because we are stepping over one
2191 in-line (in any thread), we need to receive all signals to avoid
2192 accidentally skipping a breakpoint during execution of a signal
2195 Likewise if we're displaced stepping, otherwise a trap for a
2196 breakpoint in a signal handler might be confused with the
2197 displaced step finishing. We don't make the displaced_step_fixup
2198 step distinguish the cases instead, because:
2200 - a backtrace while stopped in the signal handler would show the
2201 scratch pad as frame older than the signal handler, instead of
2202 the real mainline code.
2204 - when the thread is later resumed, the signal handler would
2205 return to the scratch pad area, which would no longer be
2207 if (step_over_info_valid_p ()
2208 || displaced_step_in_progress (tp
->inf
))
2209 target_pass_signals ({});
2211 target_pass_signals (signal_pass
);
2213 target_resume (resume_ptid
, step
, sig
);
2215 target_commit_resume ();
2218 /* Resume the inferior. SIG is the signal to give the inferior
2219 (GDB_SIGNAL_0 for none). Note: don't call this directly; instead
2220 call 'resume', which handles exceptions. */
2223 resume_1 (enum gdb_signal sig
)
2225 struct regcache
*regcache
= get_current_regcache ();
2226 struct gdbarch
*gdbarch
= regcache
->arch ();
2227 struct thread_info
*tp
= inferior_thread ();
2228 CORE_ADDR pc
= regcache_read_pc (regcache
);
2229 const address_space
*aspace
= regcache
->aspace ();
2231 /* This represents the user's step vs continue request. When
2232 deciding whether "set scheduler-locking step" applies, it's the
2233 user's intention that counts. */
2234 const int user_step
= tp
->control
.stepping_command
;
2235 /* This represents what we'll actually request the target to do.
2236 This can decay from a step to a continue, if e.g., we need to
2237 implement single-stepping with breakpoints (software
2241 gdb_assert (!tp
->stop_requested
);
2242 gdb_assert (!thread_is_in_step_over_chain (tp
));
2244 if (tp
->suspend
.waitstatus_pending_p
)
2249 = target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2251 fprintf_unfiltered (gdb_stdlog
,
2252 "infrun: resume: thread %s has pending wait "
2253 "status %s (currently_stepping=%d).\n",
2254 target_pid_to_str (tp
->ptid
).c_str (),
2256 currently_stepping (tp
));
2261 /* FIXME: What should we do if we are supposed to resume this
2262 thread with a signal? Maybe we should maintain a queue of
2263 pending signals to deliver. */
2264 if (sig
!= GDB_SIGNAL_0
)
2266 warning (_("Couldn't deliver signal %s to %s."),
2267 gdb_signal_to_name (sig
),
2268 target_pid_to_str (tp
->ptid
).c_str ());
2271 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2273 if (target_can_async_p ())
2276 /* Tell the event loop we have an event to process. */
2277 mark_async_event_handler (infrun_async_inferior_event_token
);
2282 tp
->stepped_breakpoint
= 0;
2284 /* Depends on stepped_breakpoint. */
2285 step
= currently_stepping (tp
);
2287 if (current_inferior ()->waiting_for_vfork_done
)
2289 /* Don't try to single-step a vfork parent that is waiting for
2290 the child to get out of the shared memory region (by exec'ing
2291 or exiting). This is particularly important on software
2292 single-step archs, as the child process would trip on the
2293 software single step breakpoint inserted for the parent
2294 process. Since the parent will not actually execute any
2295 instruction until the child is out of the shared region (such
2296 are vfork's semantics), it is safe to simply continue it.
2297 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2298 the parent, and tell it to `keep_going', which automatically
2299 re-sets it stepping. */
2301 fprintf_unfiltered (gdb_stdlog
,
2302 "infrun: resume : clear step\n");
2307 fprintf_unfiltered (gdb_stdlog
,
2308 "infrun: resume (step=%d, signal=%s), "
2309 "trap_expected=%d, current thread [%s] at %s\n",
2310 step
, gdb_signal_to_symbol_string (sig
),
2311 tp
->control
.trap_expected
,
2312 target_pid_to_str (inferior_ptid
).c_str (),
2313 paddress (gdbarch
, pc
));
2315 /* Normally, by the time we reach `resume', the breakpoints are either
2316 removed or inserted, as appropriate. The exception is if we're sitting
2317 at a permanent breakpoint; we need to step over it, but permanent
2318 breakpoints can't be removed. So we have to test for it here. */
2319 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2321 if (sig
!= GDB_SIGNAL_0
)
2323 /* We have a signal to pass to the inferior. The resume
2324 may, or may not take us to the signal handler. If this
2325 is a step, we'll need to stop in the signal handler, if
2326 there's one, (if the target supports stepping into
2327 handlers), or in the next mainline instruction, if
2328 there's no handler. If this is a continue, we need to be
2329 sure to run the handler with all breakpoints inserted.
2330 In all cases, set a breakpoint at the current address
2331 (where the handler returns to), and once that breakpoint
2332 is hit, resume skipping the permanent breakpoint. If
2333 that breakpoint isn't hit, then we've stepped into the
2334 signal handler (or hit some other event). We'll delete
2335 the step-resume breakpoint then. */
2338 fprintf_unfiltered (gdb_stdlog
,
2339 "infrun: resume: skipping permanent breakpoint, "
2340 "deliver signal first\n");
2342 clear_step_over_info ();
2343 tp
->control
.trap_expected
= 0;
2345 if (tp
->control
.step_resume_breakpoint
== NULL
)
2347 /* Set a "high-priority" step-resume, as we don't want
2348 user breakpoints at PC to trigger (again) when this
2350 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2351 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2353 tp
->step_after_step_resume_breakpoint
= step
;
2356 insert_breakpoints ();
2360 /* There's no signal to pass, we can go ahead and skip the
2361 permanent breakpoint manually. */
2363 fprintf_unfiltered (gdb_stdlog
,
2364 "infrun: resume: skipping permanent breakpoint\n");
2365 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2366 /* Update pc to reflect the new address from which we will
2367 execute instructions. */
2368 pc
= regcache_read_pc (regcache
);
2372 /* We've already advanced the PC, so the stepping part
2373 is done. Now we need to arrange for a trap to be
2374 reported to handle_inferior_event. Set a breakpoint
2375 at the current PC, and run to it. Don't update
2376 prev_pc, because if we end in
2377 switch_back_to_stepped_thread, we want the "expected
2378 thread advanced also" branch to be taken. IOW, we
2379 don't want this thread to step further from PC
2381 gdb_assert (!step_over_info_valid_p ());
2382 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2383 insert_breakpoints ();
2385 resume_ptid
= internal_resume_ptid (user_step
);
2386 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
2393 /* If we have a breakpoint to step over, make sure to do a single
2394 step only. Same if we have software watchpoints. */
2395 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2396 tp
->control
.may_range_step
= 0;
2398 /* If enabled, step over breakpoints by executing a copy of the
2399 instruction at a different address.
2401 We can't use displaced stepping when we have a signal to deliver;
2402 the comments for displaced_step_prepare explain why. The
2403 comments in the handle_inferior event for dealing with 'random
2404 signals' explain what we do instead.
2406 We can't use displaced stepping when we are waiting for vfork_done
2407 event, displaced stepping breaks the vfork child similarly as single
2408 step software breakpoint. */
2409 if (tp
->control
.trap_expected
2410 && use_displaced_stepping (tp
)
2411 && !step_over_info_valid_p ()
2412 && sig
== GDB_SIGNAL_0
2413 && !current_inferior ()->waiting_for_vfork_done
)
2415 int prepared
= displaced_step_prepare (tp
);
2420 fprintf_unfiltered (gdb_stdlog
,
2421 "Got placed in step-over queue\n");
2423 tp
->control
.trap_expected
= 0;
2426 else if (prepared
< 0)
2428 /* Fallback to stepping over the breakpoint in-line. */
2430 if (target_is_non_stop_p ())
2431 stop_all_threads ();
2433 set_step_over_info (regcache
->aspace (),
2434 regcache_read_pc (regcache
), 0, tp
->global_num
);
2436 step
= maybe_software_singlestep (gdbarch
, pc
);
2438 insert_breakpoints ();
2440 else if (prepared
> 0)
2442 struct displaced_step_inferior_state
*displaced
;
2444 /* Update pc to reflect the new address from which we will
2445 execute instructions due to displaced stepping. */
2446 pc
= regcache_read_pc (get_thread_regcache (tp
));
2448 displaced
= get_displaced_stepping_state (tp
->inf
);
2449 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
2450 displaced
->step_closure
);
2454 /* Do we need to do it the hard way, w/temp breakpoints? */
2456 step
= maybe_software_singlestep (gdbarch
, pc
);
2458 /* Currently, our software single-step implementation leads to different
2459 results than hardware single-stepping in one situation: when stepping
2460 into delivering a signal which has an associated signal handler,
2461 hardware single-step will stop at the first instruction of the handler,
2462 while software single-step will simply skip execution of the handler.
2464 For now, this difference in behavior is accepted since there is no
2465 easy way to actually implement single-stepping into a signal handler
2466 without kernel support.
2468 However, there is one scenario where this difference leads to follow-on
2469 problems: if we're stepping off a breakpoint by removing all breakpoints
2470 and then single-stepping. In this case, the software single-step
2471 behavior means that even if there is a *breakpoint* in the signal
2472 handler, GDB still would not stop.
2474 Fortunately, we can at least fix this particular issue. We detect
2475 here the case where we are about to deliver a signal while software
2476 single-stepping with breakpoints removed. In this situation, we
2477 revert the decisions to remove all breakpoints and insert single-
2478 step breakpoints, and instead we install a step-resume breakpoint
2479 at the current address, deliver the signal without stepping, and
2480 once we arrive back at the step-resume breakpoint, actually step
2481 over the breakpoint we originally wanted to step over. */
2482 if (thread_has_single_step_breakpoints_set (tp
)
2483 && sig
!= GDB_SIGNAL_0
2484 && step_over_info_valid_p ())
2486 /* If we have nested signals or a pending signal is delivered
2487 immediately after a handler returns, might might already have
2488 a step-resume breakpoint set on the earlier handler. We cannot
2489 set another step-resume breakpoint; just continue on until the
2490 original breakpoint is hit. */
2491 if (tp
->control
.step_resume_breakpoint
== NULL
)
2493 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2494 tp
->step_after_step_resume_breakpoint
= 1;
2497 delete_single_step_breakpoints (tp
);
2499 clear_step_over_info ();
2500 tp
->control
.trap_expected
= 0;
2502 insert_breakpoints ();
2505 /* If STEP is set, it's a request to use hardware stepping
2506 facilities. But in that case, we should never
2507 use singlestep breakpoint. */
2508 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2510 /* Decide the set of threads to ask the target to resume. */
2511 if (tp
->control
.trap_expected
)
2513 /* We're allowing a thread to run past a breakpoint it has
2514 hit, either by single-stepping the thread with the breakpoint
2515 removed, or by displaced stepping, with the breakpoint inserted.
2516 In the former case, we need to single-step only this thread,
2517 and keep others stopped, as they can miss this breakpoint if
2518 allowed to run. That's not really a problem for displaced
2519 stepping, but, we still keep other threads stopped, in case
2520 another thread is also stopped for a breakpoint waiting for
2521 its turn in the displaced stepping queue. */
2522 resume_ptid
= inferior_ptid
;
2525 resume_ptid
= internal_resume_ptid (user_step
);
2527 if (execution_direction
!= EXEC_REVERSE
2528 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2530 /* There are two cases where we currently need to step a
2531 breakpoint instruction when we have a signal to deliver:
2533 - See handle_signal_stop where we handle random signals that
2534 could take out us out of the stepping range. Normally, in
2535 that case we end up continuing (instead of stepping) over the
2536 signal handler with a breakpoint at PC, but there are cases
2537 where we should _always_ single-step, even if we have a
2538 step-resume breakpoint, like when a software watchpoint is
2539 set. Assuming single-stepping and delivering a signal at the
2540 same time would takes us to the signal handler, then we could
2541 have removed the breakpoint at PC to step over it. However,
2542 some hardware step targets (like e.g., Mac OS) can't step
2543 into signal handlers, and for those, we need to leave the
2544 breakpoint at PC inserted, as otherwise if the handler
2545 recurses and executes PC again, it'll miss the breakpoint.
2546 So we leave the breakpoint inserted anyway, but we need to
2547 record that we tried to step a breakpoint instruction, so
2548 that adjust_pc_after_break doesn't end up confused.
2550 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2551 in one thread after another thread that was stepping had been
2552 momentarily paused for a step-over. When we re-resume the
2553 stepping thread, it may be resumed from that address with a
2554 breakpoint that hasn't trapped yet. Seen with
2555 gdb.threads/non-stop-fair-events.exp, on targets that don't
2556 do displaced stepping. */
2559 fprintf_unfiltered (gdb_stdlog
,
2560 "infrun: resume: [%s] stepped breakpoint\n",
2561 target_pid_to_str (tp
->ptid
).c_str ());
2563 tp
->stepped_breakpoint
= 1;
2565 /* Most targets can step a breakpoint instruction, thus
2566 executing it normally. But if this one cannot, just
2567 continue and we will hit it anyway. */
2568 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2573 && tp
->control
.trap_expected
2574 && use_displaced_stepping (tp
)
2575 && !step_over_info_valid_p ())
2577 struct regcache
*resume_regcache
= get_thread_regcache (tp
);
2578 struct gdbarch
*resume_gdbarch
= resume_regcache
->arch ();
2579 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2582 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
2583 paddress (resume_gdbarch
, actual_pc
));
2584 read_memory (actual_pc
, buf
, sizeof (buf
));
2585 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
2588 if (tp
->control
.may_range_step
)
2590 /* If we're resuming a thread with the PC out of the step
2591 range, then we're doing some nested/finer run control
2592 operation, like stepping the thread out of the dynamic
2593 linker or the displaced stepping scratch pad. We
2594 shouldn't have allowed a range step then. */
2595 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2598 do_target_resume (resume_ptid
, step
, sig
);
2602 /* Resume the inferior. SIG is the signal to give the inferior
2603 (GDB_SIGNAL_0 for none). This is a wrapper around 'resume_1' that
2604 rolls back state on error. */
2607 resume (gdb_signal sig
)
2613 catch (const gdb_exception
&ex
)
2615 /* If resuming is being aborted for any reason, delete any
2616 single-step breakpoint resume_1 may have created, to avoid
2617 confusing the following resumption, and to avoid leaving
2618 single-step breakpoints perturbing other threads, in case
2619 we're running in non-stop mode. */
2620 if (inferior_ptid
!= null_ptid
)
2621 delete_single_step_breakpoints (inferior_thread ());
2631 /* Counter that tracks number of user visible stops. This can be used
2632 to tell whether a command has proceeded the inferior past the
2633 current location. This allows e.g., inferior function calls in
2634 breakpoint commands to not interrupt the command list. When the
2635 call finishes successfully, the inferior is standing at the same
2636 breakpoint as if nothing happened (and so we don't call
2638 static ULONGEST current_stop_id
;
2645 return current_stop_id
;
2648 /* Called when we report a user visible stop. */
2656 /* Clear out all variables saying what to do when inferior is continued.
2657 First do this, then set the ones you want, then call `proceed'. */
2660 clear_proceed_status_thread (struct thread_info
*tp
)
2663 fprintf_unfiltered (gdb_stdlog
,
2664 "infrun: clear_proceed_status_thread (%s)\n",
2665 target_pid_to_str (tp
->ptid
).c_str ());
2667 /* If we're starting a new sequence, then the previous finished
2668 single-step is no longer relevant. */
2669 if (tp
->suspend
.waitstatus_pending_p
)
2671 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
2674 fprintf_unfiltered (gdb_stdlog
,
2675 "infrun: clear_proceed_status: pending "
2676 "event of %s was a finished step. "
2678 target_pid_to_str (tp
->ptid
).c_str ());
2680 tp
->suspend
.waitstatus_pending_p
= 0;
2681 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2683 else if (debug_infrun
)
2686 = target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2688 fprintf_unfiltered (gdb_stdlog
,
2689 "infrun: clear_proceed_status_thread: thread %s "
2690 "has pending wait status %s "
2691 "(currently_stepping=%d).\n",
2692 target_pid_to_str (tp
->ptid
).c_str (),
2694 currently_stepping (tp
));
2698 /* If this signal should not be seen by program, give it zero.
2699 Used for debugging signals. */
2700 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2701 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2703 delete tp
->thread_fsm
;
2704 tp
->thread_fsm
= NULL
;
2706 tp
->control
.trap_expected
= 0;
2707 tp
->control
.step_range_start
= 0;
2708 tp
->control
.step_range_end
= 0;
2709 tp
->control
.may_range_step
= 0;
2710 tp
->control
.step_frame_id
= null_frame_id
;
2711 tp
->control
.step_stack_frame_id
= null_frame_id
;
2712 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2713 tp
->control
.step_start_function
= NULL
;
2714 tp
->stop_requested
= 0;
2716 tp
->control
.stop_step
= 0;
2718 tp
->control
.proceed_to_finish
= 0;
2720 tp
->control
.stepping_command
= 0;
2722 /* Discard any remaining commands or status from previous stop. */
2723 bpstat_clear (&tp
->control
.stop_bpstat
);
2727 clear_proceed_status (int step
)
2729 /* With scheduler-locking replay, stop replaying other threads if we're
2730 not replaying the user-visible resume ptid.
2732 This is a convenience feature to not require the user to explicitly
2733 stop replaying the other threads. We're assuming that the user's
2734 intent is to resume tracing the recorded process. */
2735 if (!non_stop
&& scheduler_mode
== schedlock_replay
2736 && target_record_is_replaying (minus_one_ptid
)
2737 && !target_record_will_replay (user_visible_resume_ptid (step
),
2738 execution_direction
))
2739 target_record_stop_replaying ();
2741 if (!non_stop
&& inferior_ptid
!= null_ptid
)
2743 ptid_t resume_ptid
= user_visible_resume_ptid (step
);
2745 /* In all-stop mode, delete the per-thread status of all threads
2746 we're about to resume, implicitly and explicitly. */
2747 for (thread_info
*tp
: all_non_exited_threads (resume_ptid
))
2748 clear_proceed_status_thread (tp
);
2751 if (inferior_ptid
!= null_ptid
)
2753 struct inferior
*inferior
;
2757 /* If in non-stop mode, only delete the per-thread status of
2758 the current thread. */
2759 clear_proceed_status_thread (inferior_thread ());
2762 inferior
= current_inferior ();
2763 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2766 gdb::observers::about_to_proceed
.notify ();
2769 /* Returns true if TP is still stopped at a breakpoint that needs
2770 stepping-over in order to make progress. If the breakpoint is gone
2771 meanwhile, we can skip the whole step-over dance. */
2774 thread_still_needs_step_over_bp (struct thread_info
*tp
)
2776 if (tp
->stepping_over_breakpoint
)
2778 struct regcache
*regcache
= get_thread_regcache (tp
);
2780 if (breakpoint_here_p (regcache
->aspace (),
2781 regcache_read_pc (regcache
))
2782 == ordinary_breakpoint_here
)
2785 tp
->stepping_over_breakpoint
= 0;
2791 /* Check whether thread TP still needs to start a step-over in order
2792 to make progress when resumed. Returns an bitwise or of enum
2793 step_over_what bits, indicating what needs to be stepped over. */
2795 static step_over_what
2796 thread_still_needs_step_over (struct thread_info
*tp
)
2798 step_over_what what
= 0;
2800 if (thread_still_needs_step_over_bp (tp
))
2801 what
|= STEP_OVER_BREAKPOINT
;
2803 if (tp
->stepping_over_watchpoint
2804 && !target_have_steppable_watchpoint
)
2805 what
|= STEP_OVER_WATCHPOINT
;
2810 /* Returns true if scheduler locking applies. STEP indicates whether
2811 we're about to do a step/next-like command to a thread. */
2814 schedlock_applies (struct thread_info
*tp
)
2816 return (scheduler_mode
== schedlock_on
2817 || (scheduler_mode
== schedlock_step
2818 && tp
->control
.stepping_command
)
2819 || (scheduler_mode
== schedlock_replay
2820 && target_record_will_replay (minus_one_ptid
,
2821 execution_direction
)));
2824 /* Basic routine for continuing the program in various fashions.
2826 ADDR is the address to resume at, or -1 for resume where stopped.
2827 SIGGNAL is the signal to give it, or GDB_SIGNAL_0 for none,
2828 or GDB_SIGNAL_DEFAULT for act according to how it stopped.
2830 You should call clear_proceed_status before calling proceed. */
2833 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
)
2835 struct regcache
*regcache
;
2836 struct gdbarch
*gdbarch
;
2839 struct execution_control_state ecss
;
2840 struct execution_control_state
*ecs
= &ecss
;
2843 /* If we're stopped at a fork/vfork, follow the branch set by the
2844 "set follow-fork-mode" command; otherwise, we'll just proceed
2845 resuming the current thread. */
2846 if (!follow_fork ())
2848 /* The target for some reason decided not to resume. */
2850 if (target_can_async_p ())
2851 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2855 /* We'll update this if & when we switch to a new thread. */
2856 previous_inferior_ptid
= inferior_ptid
;
2858 regcache
= get_current_regcache ();
2859 gdbarch
= regcache
->arch ();
2860 const address_space
*aspace
= regcache
->aspace ();
2862 pc
= regcache_read_pc (regcache
);
2863 thread_info
*cur_thr
= inferior_thread ();
2865 /* Fill in with reasonable starting values. */
2866 init_thread_stepping_state (cur_thr
);
2868 gdb_assert (!thread_is_in_step_over_chain (cur_thr
));
2870 if (addr
== (CORE_ADDR
) -1)
2872 if (pc
== cur_thr
->suspend
.stop_pc
2873 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
2874 && execution_direction
!= EXEC_REVERSE
)
2875 /* There is a breakpoint at the address we will resume at,
2876 step one instruction before inserting breakpoints so that
2877 we do not stop right away (and report a second hit at this
2880 Note, we don't do this in reverse, because we won't
2881 actually be executing the breakpoint insn anyway.
2882 We'll be (un-)executing the previous instruction. */
2883 cur_thr
->stepping_over_breakpoint
= 1;
2884 else if (gdbarch_single_step_through_delay_p (gdbarch
)
2885 && gdbarch_single_step_through_delay (gdbarch
,
2886 get_current_frame ()))
2887 /* We stepped onto an instruction that needs to be stepped
2888 again before re-inserting the breakpoint, do so. */
2889 cur_thr
->stepping_over_breakpoint
= 1;
2893 regcache_write_pc (regcache
, addr
);
2896 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
2897 cur_thr
->suspend
.stop_signal
= siggnal
;
2899 resume_ptid
= user_visible_resume_ptid (cur_thr
->control
.stepping_command
);
2901 /* If an exception is thrown from this point on, make sure to
2902 propagate GDB's knowledge of the executing state to the
2903 frontend/user running state. */
2904 scoped_finish_thread_state
finish_state (resume_ptid
);
2906 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
2907 threads (e.g., we might need to set threads stepping over
2908 breakpoints first), from the user/frontend's point of view, all
2909 threads in RESUME_PTID are now running. Unless we're calling an
2910 inferior function, as in that case we pretend the inferior
2911 doesn't run at all. */
2912 if (!cur_thr
->control
.in_infcall
)
2913 set_running (resume_ptid
, 1);
2916 fprintf_unfiltered (gdb_stdlog
,
2917 "infrun: proceed (addr=%s, signal=%s)\n",
2918 paddress (gdbarch
, addr
),
2919 gdb_signal_to_symbol_string (siggnal
));
2921 annotate_starting ();
2923 /* Make sure that output from GDB appears before output from the
2925 gdb_flush (gdb_stdout
);
2927 /* Since we've marked the inferior running, give it the terminal. A
2928 QUIT/Ctrl-C from here on is forwarded to the target (which can
2929 still detect attempts to unblock a stuck connection with repeated
2930 Ctrl-C from within target_pass_ctrlc). */
2931 target_terminal::inferior ();
2933 /* In a multi-threaded task we may select another thread and
2934 then continue or step.
2936 But if a thread that we're resuming had stopped at a breakpoint,
2937 it will immediately cause another breakpoint stop without any
2938 execution (i.e. it will report a breakpoint hit incorrectly). So
2939 we must step over it first.
2941 Look for threads other than the current (TP) that reported a
2942 breakpoint hit and haven't been resumed yet since. */
2944 /* If scheduler locking applies, we can avoid iterating over all
2946 if (!non_stop
&& !schedlock_applies (cur_thr
))
2948 for (thread_info
*tp
: all_non_exited_threads (resume_ptid
))
2950 /* Ignore the current thread here. It's handled
2955 if (!thread_still_needs_step_over (tp
))
2958 gdb_assert (!thread_is_in_step_over_chain (tp
));
2961 fprintf_unfiltered (gdb_stdlog
,
2962 "infrun: need to step-over [%s] first\n",
2963 target_pid_to_str (tp
->ptid
).c_str ());
2965 thread_step_over_chain_enqueue (tp
);
2969 /* Enqueue the current thread last, so that we move all other
2970 threads over their breakpoints first. */
2971 if (cur_thr
->stepping_over_breakpoint
)
2972 thread_step_over_chain_enqueue (cur_thr
);
2974 /* If the thread isn't started, we'll still need to set its prev_pc,
2975 so that switch_back_to_stepped_thread knows the thread hasn't
2976 advanced. Must do this before resuming any thread, as in
2977 all-stop/remote, once we resume we can't send any other packet
2978 until the target stops again. */
2979 cur_thr
->prev_pc
= regcache_read_pc (regcache
);
2982 scoped_restore save_defer_tc
= make_scoped_defer_target_commit_resume ();
2984 started
= start_step_over ();
2986 if (step_over_info_valid_p ())
2988 /* Either this thread started a new in-line step over, or some
2989 other thread was already doing one. In either case, don't
2990 resume anything else until the step-over is finished. */
2992 else if (started
&& !target_is_non_stop_p ())
2994 /* A new displaced stepping sequence was started. In all-stop,
2995 we can't talk to the target anymore until it next stops. */
2997 else if (!non_stop
&& target_is_non_stop_p ())
2999 /* In all-stop, but the target is always in non-stop mode.
3000 Start all other threads that are implicitly resumed too. */
3001 for (thread_info
*tp
: all_non_exited_threads (resume_ptid
))
3006 fprintf_unfiltered (gdb_stdlog
,
3007 "infrun: proceed: [%s] resumed\n",
3008 target_pid_to_str (tp
->ptid
).c_str ());
3009 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
3013 if (thread_is_in_step_over_chain (tp
))
3016 fprintf_unfiltered (gdb_stdlog
,
3017 "infrun: proceed: [%s] needs step-over\n",
3018 target_pid_to_str (tp
->ptid
).c_str ());
3023 fprintf_unfiltered (gdb_stdlog
,
3024 "infrun: proceed: resuming %s\n",
3025 target_pid_to_str (tp
->ptid
).c_str ());
3027 reset_ecs (ecs
, tp
);
3028 switch_to_thread (tp
);
3029 keep_going_pass_signal (ecs
);
3030 if (!ecs
->wait_some_more
)
3031 error (_("Command aborted."));
3034 else if (!cur_thr
->resumed
&& !thread_is_in_step_over_chain (cur_thr
))
3036 /* The thread wasn't started, and isn't queued, run it now. */
3037 reset_ecs (ecs
, cur_thr
);
3038 switch_to_thread (cur_thr
);
3039 keep_going_pass_signal (ecs
);
3040 if (!ecs
->wait_some_more
)
3041 error (_("Command aborted."));
3045 target_commit_resume ();
3047 finish_state
.release ();
3049 /* Tell the event loop to wait for it to stop. If the target
3050 supports asynchronous execution, it'll do this from within
3052 if (!target_can_async_p ())
3053 mark_async_event_handler (infrun_async_inferior_event_token
);
3057 /* Start remote-debugging of a machine over a serial link. */
3060 start_remote (int from_tty
)
3062 struct inferior
*inferior
;
3064 inferior
= current_inferior ();
3065 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
3067 /* Always go on waiting for the target, regardless of the mode. */
3068 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3069 indicate to wait_for_inferior that a target should timeout if
3070 nothing is returned (instead of just blocking). Because of this,
3071 targets expecting an immediate response need to, internally, set
3072 things up so that the target_wait() is forced to eventually
3074 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3075 differentiate to its caller what the state of the target is after
3076 the initial open has been performed. Here we're assuming that
3077 the target has stopped. It should be possible to eventually have
3078 target_open() return to the caller an indication that the target
3079 is currently running and GDB state should be set to the same as
3080 for an async run. */
3081 wait_for_inferior ();
3083 /* Now that the inferior has stopped, do any bookkeeping like
3084 loading shared libraries. We want to do this before normal_stop,
3085 so that the displayed frame is up to date. */
3086 post_create_inferior (current_top_target (), from_tty
);
3091 /* Initialize static vars when a new inferior begins. */
3094 init_wait_for_inferior (void)
3096 /* These are meaningless until the first time through wait_for_inferior. */
3098 breakpoint_init_inferior (inf_starting
);
3100 clear_proceed_status (0);
3102 target_last_wait_ptid
= minus_one_ptid
;
3104 previous_inferior_ptid
= inferior_ptid
;
3109 static void handle_inferior_event (struct execution_control_state
*ecs
);
3111 static void handle_step_into_function (struct gdbarch
*gdbarch
,
3112 struct execution_control_state
*ecs
);
3113 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
3114 struct execution_control_state
*ecs
);
3115 static void handle_signal_stop (struct execution_control_state
*ecs
);
3116 static void check_exception_resume (struct execution_control_state
*,
3117 struct frame_info
*);
3119 static void end_stepping_range (struct execution_control_state
*ecs
);
3120 static void stop_waiting (struct execution_control_state
*ecs
);
3121 static void keep_going (struct execution_control_state
*ecs
);
3122 static void process_event_stop_test (struct execution_control_state
*ecs
);
3123 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
3125 /* This function is attached as a "thread_stop_requested" observer.
3126 Cleanup local state that assumed the PTID was to be resumed, and
3127 report the stop to the frontend. */
3130 infrun_thread_stop_requested (ptid_t ptid
)
3132 /* PTID was requested to stop. If the thread was already stopped,
3133 but the user/frontend doesn't know about that yet (e.g., the
3134 thread had been temporarily paused for some step-over), set up
3135 for reporting the stop now. */
3136 for (thread_info
*tp
: all_threads (ptid
))
3138 if (tp
->state
!= THREAD_RUNNING
)
3143 /* Remove matching threads from the step-over queue, so
3144 start_step_over doesn't try to resume them
3146 if (thread_is_in_step_over_chain (tp
))
3147 thread_step_over_chain_remove (tp
);
3149 /* If the thread is stopped, but the user/frontend doesn't
3150 know about that yet, queue a pending event, as if the
3151 thread had just stopped now. Unless the thread already had
3153 if (!tp
->suspend
.waitstatus_pending_p
)
3155 tp
->suspend
.waitstatus_pending_p
= 1;
3156 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_STOPPED
;
3157 tp
->suspend
.waitstatus
.value
.sig
= GDB_SIGNAL_0
;
3160 /* Clear the inline-frame state, since we're re-processing the
3162 clear_inline_frame_state (tp
->ptid
);
3164 /* If this thread was paused because some other thread was
3165 doing an inline-step over, let that finish first. Once
3166 that happens, we'll restart all threads and consume pending
3167 stop events then. */
3168 if (step_over_info_valid_p ())
3171 /* Otherwise we can process the (new) pending event now. Set
3172 it so this pending event is considered by
3179 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
3181 if (target_last_wait_ptid
== tp
->ptid
)
3182 nullify_last_target_wait_ptid ();
3185 /* Delete the step resume, single-step and longjmp/exception resume
3186 breakpoints of TP. */
3189 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
3191 delete_step_resume_breakpoint (tp
);
3192 delete_exception_resume_breakpoint (tp
);
3193 delete_single_step_breakpoints (tp
);
3196 /* If the target still has execution, call FUNC for each thread that
3197 just stopped. In all-stop, that's all the non-exited threads; in
3198 non-stop, that's the current thread, only. */
3200 typedef void (*for_each_just_stopped_thread_callback_func
)
3201 (struct thread_info
*tp
);
3204 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
3206 if (!target_has_execution
|| inferior_ptid
== null_ptid
)
3209 if (target_is_non_stop_p ())
3211 /* If in non-stop mode, only the current thread stopped. */
3212 func (inferior_thread ());
3216 /* In all-stop mode, all threads have stopped. */
3217 for (thread_info
*tp
: all_non_exited_threads ())
3222 /* Delete the step resume and longjmp/exception resume breakpoints of
3223 the threads that just stopped. */
3226 delete_just_stopped_threads_infrun_breakpoints (void)
3228 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3231 /* Delete the single-step breakpoints of the threads that just
3235 delete_just_stopped_threads_single_step_breakpoints (void)
3237 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3243 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3244 const struct target_waitstatus
*ws
)
3246 std::string status_string
= target_waitstatus_to_string (ws
);
3249 /* The text is split over several lines because it was getting too long.
3250 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3251 output as a unit; we want only one timestamp printed if debug_timestamp
3254 stb
.printf ("infrun: target_wait (%d.%ld.%ld",
3257 waiton_ptid
.tid ());
3258 if (waiton_ptid
.pid () != -1)
3259 stb
.printf (" [%s]", target_pid_to_str (waiton_ptid
).c_str ());
3260 stb
.printf (", status) =\n");
3261 stb
.printf ("infrun: %d.%ld.%ld [%s],\n",
3265 target_pid_to_str (result_ptid
).c_str ());
3266 stb
.printf ("infrun: %s\n", status_string
.c_str ());
3268 /* This uses %s in part to handle %'s in the text, but also to avoid
3269 a gcc error: the format attribute requires a string literal. */
3270 fprintf_unfiltered (gdb_stdlog
, "%s", stb
.c_str ());
3273 /* Select a thread at random, out of those which are resumed and have
3276 static struct thread_info
*
3277 random_pending_event_thread (ptid_t waiton_ptid
)
3281 auto has_event
= [] (thread_info
*tp
)
3284 && tp
->suspend
.waitstatus_pending_p
);
3287 /* First see how many events we have. Count only resumed threads
3288 that have an event pending. */
3289 for (thread_info
*tp
: all_non_exited_threads (waiton_ptid
))
3293 if (num_events
== 0)
3296 /* Now randomly pick a thread out of those that have had events. */
3297 int random_selector
= (int) ((num_events
* (double) rand ())
3298 / (RAND_MAX
+ 1.0));
3300 if (debug_infrun
&& num_events
> 1)
3301 fprintf_unfiltered (gdb_stdlog
,
3302 "infrun: Found %d events, selecting #%d\n",
3303 num_events
, random_selector
);
3305 /* Select the Nth thread that has had an event. */
3306 for (thread_info
*tp
: all_non_exited_threads (waiton_ptid
))
3308 if (random_selector
-- == 0)
3311 gdb_assert_not_reached ("event thread not found");
3314 /* Wrapper for target_wait that first checks whether threads have
3315 pending statuses to report before actually asking the target for
3319 do_target_wait (ptid_t ptid
, struct target_waitstatus
*status
, int options
)
3322 struct thread_info
*tp
;
3324 /* First check if there is a resumed thread with a wait status
3326 if (ptid
== minus_one_ptid
|| ptid
.is_pid ())
3328 tp
= random_pending_event_thread (ptid
);
3333 fprintf_unfiltered (gdb_stdlog
,
3334 "infrun: Waiting for specific thread %s.\n",
3335 target_pid_to_str (ptid
).c_str ());
3337 /* We have a specific thread to check. */
3338 tp
= find_thread_ptid (ptid
);
3339 gdb_assert (tp
!= NULL
);
3340 if (!tp
->suspend
.waitstatus_pending_p
)
3345 && (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3346 || tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
3348 struct regcache
*regcache
= get_thread_regcache (tp
);
3349 struct gdbarch
*gdbarch
= regcache
->arch ();
3353 pc
= regcache_read_pc (regcache
);
3355 if (pc
!= tp
->suspend
.stop_pc
)
3358 fprintf_unfiltered (gdb_stdlog
,
3359 "infrun: PC of %s changed. was=%s, now=%s\n",
3360 target_pid_to_str (tp
->ptid
).c_str (),
3361 paddress (gdbarch
, tp
->suspend
.stop_pc
),
3362 paddress (gdbarch
, pc
));
3365 else if (!breakpoint_inserted_here_p (regcache
->aspace (), pc
))
3368 fprintf_unfiltered (gdb_stdlog
,
3369 "infrun: previous breakpoint of %s, at %s gone\n",
3370 target_pid_to_str (tp
->ptid
).c_str (),
3371 paddress (gdbarch
, pc
));
3379 fprintf_unfiltered (gdb_stdlog
,
3380 "infrun: pending event of %s cancelled.\n",
3381 target_pid_to_str (tp
->ptid
).c_str ());
3383 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_SPURIOUS
;
3384 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3393 = target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
3395 fprintf_unfiltered (gdb_stdlog
,
3396 "infrun: Using pending wait status %s for %s.\n",
3398 target_pid_to_str (tp
->ptid
).c_str ());
3401 /* Now that we've selected our final event LWP, un-adjust its PC
3402 if it was a software breakpoint (and the target doesn't
3403 always adjust the PC itself). */
3404 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3405 && !target_supports_stopped_by_sw_breakpoint ())
3407 struct regcache
*regcache
;
3408 struct gdbarch
*gdbarch
;
3411 regcache
= get_thread_regcache (tp
);
3412 gdbarch
= regcache
->arch ();
3414 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3419 pc
= regcache_read_pc (regcache
);
3420 regcache_write_pc (regcache
, pc
+ decr_pc
);
3424 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3425 *status
= tp
->suspend
.waitstatus
;
3426 tp
->suspend
.waitstatus_pending_p
= 0;
3428 /* Wake up the event loop again, until all pending events are
3430 if (target_is_async_p ())
3431 mark_async_event_handler (infrun_async_inferior_event_token
);
3435 /* But if we don't find one, we'll have to wait. */
3437 if (deprecated_target_wait_hook
)
3438 event_ptid
= deprecated_target_wait_hook (ptid
, status
, options
);
3440 event_ptid
= target_wait (ptid
, status
, options
);
3445 /* Prepare and stabilize the inferior for detaching it. E.g.,
3446 detaching while a thread is displaced stepping is a recipe for
3447 crashing it, as nothing would readjust the PC out of the scratch
3451 prepare_for_detach (void)
3453 struct inferior
*inf
= current_inferior ();
3454 ptid_t pid_ptid
= ptid_t (inf
->pid
);
3456 displaced_step_inferior_state
*displaced
= get_displaced_stepping_state (inf
);
3458 /* Is any thread of this process displaced stepping? If not,
3459 there's nothing else to do. */
3460 if (displaced
->step_thread
== nullptr)
3464 fprintf_unfiltered (gdb_stdlog
,
3465 "displaced-stepping in-process while detaching");
3467 scoped_restore restore_detaching
= make_scoped_restore (&inf
->detaching
, true);
3469 while (displaced
->step_thread
!= nullptr)
3471 struct execution_control_state ecss
;
3472 struct execution_control_state
*ecs
;
3475 memset (ecs
, 0, sizeof (*ecs
));
3477 overlay_cache_invalid
= 1;
3478 /* Flush target cache before starting to handle each event.
3479 Target was running and cache could be stale. This is just a
3480 heuristic. Running threads may modify target memory, but we
3481 don't get any event. */
3482 target_dcache_invalidate ();
3484 ecs
->ptid
= do_target_wait (pid_ptid
, &ecs
->ws
, 0);
3487 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
3489 /* If an error happens while handling the event, propagate GDB's
3490 knowledge of the executing state to the frontend/user running
3492 scoped_finish_thread_state
finish_state (minus_one_ptid
);
3494 /* Now figure out what to do with the result of the result. */
3495 handle_inferior_event (ecs
);
3497 /* No error, don't finish the state yet. */
3498 finish_state
.release ();
3500 /* Breakpoints and watchpoints are not installed on the target
3501 at this point, and signals are passed directly to the
3502 inferior, so this must mean the process is gone. */
3503 if (!ecs
->wait_some_more
)
3505 restore_detaching
.release ();
3506 error (_("Program exited while detaching"));
3510 restore_detaching
.release ();
3513 /* Wait for control to return from inferior to debugger.
3515 If inferior gets a signal, we may decide to start it up again
3516 instead of returning. That is why there is a loop in this function.
3517 When this function actually returns it means the inferior
3518 should be left stopped and GDB should read more commands. */
3521 wait_for_inferior (void)
3525 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
3527 SCOPE_EXIT
{ delete_just_stopped_threads_infrun_breakpoints (); };
3529 /* If an error happens while handling the event, propagate GDB's
3530 knowledge of the executing state to the frontend/user running
3532 scoped_finish_thread_state
finish_state (minus_one_ptid
);
3536 struct execution_control_state ecss
;
3537 struct execution_control_state
*ecs
= &ecss
;
3538 ptid_t waiton_ptid
= minus_one_ptid
;
3540 memset (ecs
, 0, sizeof (*ecs
));
3542 overlay_cache_invalid
= 1;
3544 /* Flush target cache before starting to handle each event.
3545 Target was running and cache could be stale. This is just a
3546 heuristic. Running threads may modify target memory, but we
3547 don't get any event. */
3548 target_dcache_invalidate ();
3550 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
, 0);
3553 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3555 /* Now figure out what to do with the result of the result. */
3556 handle_inferior_event (ecs
);
3558 if (!ecs
->wait_some_more
)
3562 /* No error, don't finish the state yet. */
3563 finish_state
.release ();
3566 /* Cleanup that reinstalls the readline callback handler, if the
3567 target is running in the background. If while handling the target
3568 event something triggered a secondary prompt, like e.g., a
3569 pagination prompt, we'll have removed the callback handler (see
3570 gdb_readline_wrapper_line). Need to do this as we go back to the
3571 event loop, ready to process further input. Note this has no
3572 effect if the handler hasn't actually been removed, because calling
3573 rl_callback_handler_install resets the line buffer, thus losing
3577 reinstall_readline_callback_handler_cleanup ()
3579 struct ui
*ui
= current_ui
;
3583 /* We're not going back to the top level event loop yet. Don't
3584 install the readline callback, as it'd prep the terminal,
3585 readline-style (raw, noecho) (e.g., --batch). We'll install
3586 it the next time the prompt is displayed, when we're ready
3591 if (ui
->command_editing
&& ui
->prompt_state
!= PROMPT_BLOCKED
)
3592 gdb_rl_callback_handler_reinstall ();
3595 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3596 that's just the event thread. In all-stop, that's all threads. */
3599 clean_up_just_stopped_threads_fsms (struct execution_control_state
*ecs
)
3601 if (ecs
->event_thread
!= NULL
3602 && ecs
->event_thread
->thread_fsm
!= NULL
)
3603 ecs
->event_thread
->thread_fsm
->clean_up (ecs
->event_thread
);
3607 for (thread_info
*thr
: all_non_exited_threads ())
3609 if (thr
->thread_fsm
== NULL
)
3611 if (thr
== ecs
->event_thread
)
3614 switch_to_thread (thr
);
3615 thr
->thread_fsm
->clean_up (thr
);
3618 if (ecs
->event_thread
!= NULL
)
3619 switch_to_thread (ecs
->event_thread
);
3623 /* Helper for all_uis_check_sync_execution_done that works on the
3627 check_curr_ui_sync_execution_done (void)
3629 struct ui
*ui
= current_ui
;
3631 if (ui
->prompt_state
== PROMPT_NEEDED
3633 && !gdb_in_secondary_prompt_p (ui
))
3635 target_terminal::ours ();
3636 gdb::observers::sync_execution_done
.notify ();
3637 ui_register_input_event_handler (ui
);
3644 all_uis_check_sync_execution_done (void)
3646 SWITCH_THRU_ALL_UIS ()
3648 check_curr_ui_sync_execution_done ();
3655 all_uis_on_sync_execution_starting (void)
3657 SWITCH_THRU_ALL_UIS ()
3659 if (current_ui
->prompt_state
== PROMPT_NEEDED
)
3660 async_disable_stdin ();
3664 /* Asynchronous version of wait_for_inferior. It is called by the
3665 event loop whenever a change of state is detected on the file
3666 descriptor corresponding to the target. It can be called more than
3667 once to complete a single execution command. In such cases we need
3668 to keep the state in a global variable ECSS. If it is the last time
3669 that this function is called for a single execution command, then
3670 report to the user that the inferior has stopped, and do the
3671 necessary cleanups. */
3674 fetch_inferior_event (void *client_data
)
3676 struct execution_control_state ecss
;
3677 struct execution_control_state
*ecs
= &ecss
;
3679 ptid_t waiton_ptid
= minus_one_ptid
;
3681 memset (ecs
, 0, sizeof (*ecs
));
3683 /* Events are always processed with the main UI as current UI. This
3684 way, warnings, debug output, etc. are always consistently sent to
3685 the main console. */
3686 scoped_restore save_ui
= make_scoped_restore (¤t_ui
, main_ui
);
3688 /* End up with readline processing input, if necessary. */
3690 SCOPE_EXIT
{ reinstall_readline_callback_handler_cleanup (); };
3692 /* We're handling a live event, so make sure we're doing live
3693 debugging. If we're looking at traceframes while the target is
3694 running, we're going to need to get back to that mode after
3695 handling the event. */
3696 gdb::optional
<scoped_restore_current_traceframe
> maybe_restore_traceframe
;
3699 maybe_restore_traceframe
.emplace ();
3700 set_current_traceframe (-1);
3703 gdb::optional
<scoped_restore_current_thread
> maybe_restore_thread
;
3706 /* In non-stop mode, the user/frontend should not notice a thread
3707 switch due to internal events. Make sure we reverse to the
3708 user selected thread and frame after handling the event and
3709 running any breakpoint commands. */
3710 maybe_restore_thread
.emplace ();
3712 overlay_cache_invalid
= 1;
3713 /* Flush target cache before starting to handle each event. Target
3714 was running and cache could be stale. This is just a heuristic.
3715 Running threads may modify target memory, but we don't get any
3717 target_dcache_invalidate ();
3719 scoped_restore save_exec_dir
3720 = make_scoped_restore (&execution_direction
,
3721 target_execution_direction ());
3723 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
,
3724 target_can_async_p () ? TARGET_WNOHANG
: 0);
3727 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3729 /* If an error happens while handling the event, propagate GDB's
3730 knowledge of the executing state to the frontend/user running
3732 ptid_t finish_ptid
= !target_is_non_stop_p () ? minus_one_ptid
: ecs
->ptid
;
3733 scoped_finish_thread_state
finish_state (finish_ptid
);
3735 /* Get executed before scoped_restore_current_thread above to apply
3736 still for the thread which has thrown the exception. */
3737 auto defer_bpstat_clear
3738 = make_scope_exit (bpstat_clear_actions
);
3739 auto defer_delete_threads
3740 = make_scope_exit (delete_just_stopped_threads_infrun_breakpoints
);
3742 /* Now figure out what to do with the result of the result. */
3743 handle_inferior_event (ecs
);
3745 if (!ecs
->wait_some_more
)
3747 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
3748 int should_stop
= 1;
3749 struct thread_info
*thr
= ecs
->event_thread
;
3751 delete_just_stopped_threads_infrun_breakpoints ();
3755 struct thread_fsm
*thread_fsm
= thr
->thread_fsm
;
3757 if (thread_fsm
!= NULL
)
3758 should_stop
= thread_fsm
->should_stop (thr
);
3767 bool should_notify_stop
= true;
3770 clean_up_just_stopped_threads_fsms (ecs
);
3772 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3773 should_notify_stop
= thr
->thread_fsm
->should_notify_stop ();
3775 if (should_notify_stop
)
3777 /* We may not find an inferior if this was a process exit. */
3778 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
3779 proceeded
= normal_stop ();
3784 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3790 defer_delete_threads
.release ();
3791 defer_bpstat_clear
.release ();
3793 /* No error, don't finish the thread states yet. */
3794 finish_state
.release ();
3796 /* This scope is used to ensure that readline callbacks are
3797 reinstalled here. */
3800 /* If a UI was in sync execution mode, and now isn't, restore its
3801 prompt (a synchronous execution command has finished, and we're
3802 ready for input). */
3803 all_uis_check_sync_execution_done ();
3806 && exec_done_display_p
3807 && (inferior_ptid
== null_ptid
3808 || inferior_thread ()->state
!= THREAD_RUNNING
))
3809 printf_unfiltered (_("completed.\n"));
3812 /* Record the frame and location we're currently stepping through. */
3814 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
3816 struct thread_info
*tp
= inferior_thread ();
3818 tp
->control
.step_frame_id
= get_frame_id (frame
);
3819 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
3821 tp
->current_symtab
= sal
.symtab
;
3822 tp
->current_line
= sal
.line
;
3825 /* Clear context switchable stepping state. */
3828 init_thread_stepping_state (struct thread_info
*tss
)
3830 tss
->stepped_breakpoint
= 0;
3831 tss
->stepping_over_breakpoint
= 0;
3832 tss
->stepping_over_watchpoint
= 0;
3833 tss
->step_after_step_resume_breakpoint
= 0;
3836 /* Set the cached copy of the last ptid/waitstatus. */
3839 set_last_target_status (ptid_t ptid
, struct target_waitstatus status
)
3841 target_last_wait_ptid
= ptid
;
3842 target_last_waitstatus
= status
;
3845 /* Return the cached copy of the last pid/waitstatus returned by
3846 target_wait()/deprecated_target_wait_hook(). The data is actually
3847 cached by handle_inferior_event(), which gets called immediately
3848 after target_wait()/deprecated_target_wait_hook(). */
3851 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
3853 *ptidp
= target_last_wait_ptid
;
3854 *status
= target_last_waitstatus
;
3858 nullify_last_target_wait_ptid (void)
3860 target_last_wait_ptid
= minus_one_ptid
;
3863 /* Switch thread contexts. */
3866 context_switch (execution_control_state
*ecs
)
3869 && ecs
->ptid
!= inferior_ptid
3870 && ecs
->event_thread
!= inferior_thread ())
3872 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
3873 target_pid_to_str (inferior_ptid
).c_str ());
3874 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
3875 target_pid_to_str (ecs
->ptid
).c_str ());
3878 switch_to_thread (ecs
->event_thread
);
3881 /* If the target can't tell whether we've hit breakpoints
3882 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
3883 check whether that could have been caused by a breakpoint. If so,
3884 adjust the PC, per gdbarch_decr_pc_after_break. */
3887 adjust_pc_after_break (struct thread_info
*thread
,
3888 struct target_waitstatus
*ws
)
3890 struct regcache
*regcache
;
3891 struct gdbarch
*gdbarch
;
3892 CORE_ADDR breakpoint_pc
, decr_pc
;
3894 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
3895 we aren't, just return.
3897 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
3898 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
3899 implemented by software breakpoints should be handled through the normal
3902 NOTE drow/2004-01-31: On some targets, breakpoints may generate
3903 different signals (SIGILL or SIGEMT for instance), but it is less
3904 clear where the PC is pointing afterwards. It may not match
3905 gdbarch_decr_pc_after_break. I don't know any specific target that
3906 generates these signals at breakpoints (the code has been in GDB since at
3907 least 1992) so I can not guess how to handle them here.
3909 In earlier versions of GDB, a target with
3910 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
3911 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
3912 target with both of these set in GDB history, and it seems unlikely to be
3913 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
3915 if (ws
->kind
!= TARGET_WAITKIND_STOPPED
)
3918 if (ws
->value
.sig
!= GDB_SIGNAL_TRAP
)
3921 /* In reverse execution, when a breakpoint is hit, the instruction
3922 under it has already been de-executed. The reported PC always
3923 points at the breakpoint address, so adjusting it further would
3924 be wrong. E.g., consider this case on a decr_pc_after_break == 1
3927 B1 0x08000000 : INSN1
3928 B2 0x08000001 : INSN2
3930 PC -> 0x08000003 : INSN4
3932 Say you're stopped at 0x08000003 as above. Reverse continuing
3933 from that point should hit B2 as below. Reading the PC when the
3934 SIGTRAP is reported should read 0x08000001 and INSN2 should have
3935 been de-executed already.
3937 B1 0x08000000 : INSN1
3938 B2 PC -> 0x08000001 : INSN2
3942 We can't apply the same logic as for forward execution, because
3943 we would wrongly adjust the PC to 0x08000000, since there's a
3944 breakpoint at PC - 1. We'd then report a hit on B1, although
3945 INSN1 hadn't been de-executed yet. Doing nothing is the correct
3947 if (execution_direction
== EXEC_REVERSE
)
3950 /* If the target can tell whether the thread hit a SW breakpoint,
3951 trust it. Targets that can tell also adjust the PC
3953 if (target_supports_stopped_by_sw_breakpoint ())
3956 /* Note that relying on whether a breakpoint is planted in memory to
3957 determine this can fail. E.g,. the breakpoint could have been
3958 removed since. Or the thread could have been told to step an
3959 instruction the size of a breakpoint instruction, and only
3960 _after_ was a breakpoint inserted at its address. */
3962 /* If this target does not decrement the PC after breakpoints, then
3963 we have nothing to do. */
3964 regcache
= get_thread_regcache (thread
);
3965 gdbarch
= regcache
->arch ();
3967 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3971 const address_space
*aspace
= regcache
->aspace ();
3973 /* Find the location where (if we've hit a breakpoint) the
3974 breakpoint would be. */
3975 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
3977 /* If the target can't tell whether a software breakpoint triggered,
3978 fallback to figuring it out based on breakpoints we think were
3979 inserted in the target, and on whether the thread was stepped or
3982 /* Check whether there actually is a software breakpoint inserted at
3985 If in non-stop mode, a race condition is possible where we've
3986 removed a breakpoint, but stop events for that breakpoint were
3987 already queued and arrive later. To suppress those spurious
3988 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
3989 and retire them after a number of stop events are reported. Note
3990 this is an heuristic and can thus get confused. The real fix is
3991 to get the "stopped by SW BP and needs adjustment" info out of
3992 the target/kernel (and thus never reach here; see above). */
3993 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
3994 || (target_is_non_stop_p ()
3995 && moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
3997 gdb::optional
<scoped_restore_tmpl
<int>> restore_operation_disable
;
3999 if (record_full_is_used ())
4000 restore_operation_disable
.emplace
4001 (record_full_gdb_operation_disable_set ());
4003 /* When using hardware single-step, a SIGTRAP is reported for both
4004 a completed single-step and a software breakpoint. Need to
4005 differentiate between the two, as the latter needs adjusting
4006 but the former does not.
4008 The SIGTRAP can be due to a completed hardware single-step only if
4009 - we didn't insert software single-step breakpoints
4010 - this thread is currently being stepped
4012 If any of these events did not occur, we must have stopped due
4013 to hitting a software breakpoint, and have to back up to the
4016 As a special case, we could have hardware single-stepped a
4017 software breakpoint. In this case (prev_pc == breakpoint_pc),
4018 we also need to back up to the breakpoint address. */
4020 if (thread_has_single_step_breakpoints_set (thread
)
4021 || !currently_stepping (thread
)
4022 || (thread
->stepped_breakpoint
4023 && thread
->prev_pc
== breakpoint_pc
))
4024 regcache_write_pc (regcache
, breakpoint_pc
);
4029 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
4031 for (frame
= get_prev_frame (frame
);
4033 frame
= get_prev_frame (frame
))
4035 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
4037 if (get_frame_type (frame
) != INLINE_FRAME
)
4044 /* If the event thread has the stop requested flag set, pretend it
4045 stopped for a GDB_SIGNAL_0 (i.e., as if it stopped due to
4049 handle_stop_requested (struct execution_control_state
*ecs
)
4051 if (ecs
->event_thread
->stop_requested
)
4053 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
4054 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
4055 handle_signal_stop (ecs
);
4061 /* Auxiliary function that handles syscall entry/return events.
4062 It returns 1 if the inferior should keep going (and GDB
4063 should ignore the event), or 0 if the event deserves to be
4067 handle_syscall_event (struct execution_control_state
*ecs
)
4069 struct regcache
*regcache
;
4072 context_switch (ecs
);
4074 regcache
= get_thread_regcache (ecs
->event_thread
);
4075 syscall_number
= ecs
->ws
.value
.syscall_number
;
4076 ecs
->event_thread
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4078 if (catch_syscall_enabled () > 0
4079 && catching_syscall_number (syscall_number
) > 0)
4082 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
4085 ecs
->event_thread
->control
.stop_bpstat
4086 = bpstat_stop_status (regcache
->aspace (),
4087 ecs
->event_thread
->suspend
.stop_pc
,
4088 ecs
->event_thread
, &ecs
->ws
);
4090 if (handle_stop_requested (ecs
))
4093 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4095 /* Catchpoint hit. */
4100 if (handle_stop_requested (ecs
))
4103 /* If no catchpoint triggered for this, then keep going. */
4108 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4111 fill_in_stop_func (struct gdbarch
*gdbarch
,
4112 struct execution_control_state
*ecs
)
4114 if (!ecs
->stop_func_filled_in
)
4118 /* Don't care about return value; stop_func_start and stop_func_name
4119 will both be 0 if it doesn't work. */
4120 find_pc_partial_function (ecs
->event_thread
->suspend
.stop_pc
,
4121 &ecs
->stop_func_name
,
4122 &ecs
->stop_func_start
,
4123 &ecs
->stop_func_end
,
4126 /* The call to find_pc_partial_function, above, will set
4127 stop_func_start and stop_func_end to the start and end
4128 of the range containing the stop pc. If this range
4129 contains the entry pc for the block (which is always the
4130 case for contiguous blocks), advance stop_func_start past
4131 the function's start offset and entrypoint. Note that
4132 stop_func_start is NOT advanced when in a range of a
4133 non-contiguous block that does not contain the entry pc. */
4134 if (block
!= nullptr
4135 && ecs
->stop_func_start
<= BLOCK_ENTRY_PC (block
)
4136 && BLOCK_ENTRY_PC (block
) < ecs
->stop_func_end
)
4138 ecs
->stop_func_start
4139 += gdbarch_deprecated_function_start_offset (gdbarch
);
4141 if (gdbarch_skip_entrypoint_p (gdbarch
))
4142 ecs
->stop_func_start
4143 = gdbarch_skip_entrypoint (gdbarch
, ecs
->stop_func_start
);
4146 ecs
->stop_func_filled_in
= 1;
4151 /* Return the STOP_SOON field of the inferior pointed at by ECS. */
4153 static enum stop_kind
4154 get_inferior_stop_soon (execution_control_state
*ecs
)
4156 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
4158 gdb_assert (inf
!= NULL
);
4159 return inf
->control
.stop_soon
;
4162 /* Wait for one event. Store the resulting waitstatus in WS, and
4163 return the event ptid. */
4166 wait_one (struct target_waitstatus
*ws
)
4169 ptid_t wait_ptid
= minus_one_ptid
;
4171 overlay_cache_invalid
= 1;
4173 /* Flush target cache before starting to handle each event.
4174 Target was running and cache could be stale. This is just a
4175 heuristic. Running threads may modify target memory, but we
4176 don't get any event. */
4177 target_dcache_invalidate ();
4179 if (deprecated_target_wait_hook
)
4180 event_ptid
= deprecated_target_wait_hook (wait_ptid
, ws
, 0);
4182 event_ptid
= target_wait (wait_ptid
, ws
, 0);
4185 print_target_wait_results (wait_ptid
, event_ptid
, ws
);
4190 /* Generate a wrapper for target_stopped_by_REASON that works on PTID
4191 instead of the current thread. */
4192 #define THREAD_STOPPED_BY(REASON) \
4194 thread_stopped_by_ ## REASON (ptid_t ptid) \
4196 scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid); \
4197 inferior_ptid = ptid; \
4199 return target_stopped_by_ ## REASON (); \
4202 /* Generate thread_stopped_by_watchpoint. */
4203 THREAD_STOPPED_BY (watchpoint
)
4204 /* Generate thread_stopped_by_sw_breakpoint. */
4205 THREAD_STOPPED_BY (sw_breakpoint
)
4206 /* Generate thread_stopped_by_hw_breakpoint. */
4207 THREAD_STOPPED_BY (hw_breakpoint
)
4209 /* Save the thread's event and stop reason to process it later. */
4212 save_waitstatus (struct thread_info
*tp
, struct target_waitstatus
*ws
)
4216 std::string statstr
= target_waitstatus_to_string (ws
);
4218 fprintf_unfiltered (gdb_stdlog
,
4219 "infrun: saving status %s for %d.%ld.%ld\n",
4226 /* Record for later. */
4227 tp
->suspend
.waitstatus
= *ws
;
4228 tp
->suspend
.waitstatus_pending_p
= 1;
4230 struct regcache
*regcache
= get_thread_regcache (tp
);
4231 const address_space
*aspace
= regcache
->aspace ();
4233 if (ws
->kind
== TARGET_WAITKIND_STOPPED
4234 && ws
->value
.sig
== GDB_SIGNAL_TRAP
)
4236 CORE_ADDR pc
= regcache_read_pc (regcache
);
4238 adjust_pc_after_break (tp
, &tp
->suspend
.waitstatus
);
4240 if (thread_stopped_by_watchpoint (tp
->ptid
))
4242 tp
->suspend
.stop_reason
4243 = TARGET_STOPPED_BY_WATCHPOINT
;
4245 else if (target_supports_stopped_by_sw_breakpoint ()
4246 && thread_stopped_by_sw_breakpoint (tp
->ptid
))
4248 tp
->suspend
.stop_reason
4249 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4251 else if (target_supports_stopped_by_hw_breakpoint ()
4252 && thread_stopped_by_hw_breakpoint (tp
->ptid
))
4254 tp
->suspend
.stop_reason
4255 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4257 else if (!target_supports_stopped_by_hw_breakpoint ()
4258 && hardware_breakpoint_inserted_here_p (aspace
,
4261 tp
->suspend
.stop_reason
4262 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4264 else if (!target_supports_stopped_by_sw_breakpoint ()
4265 && software_breakpoint_inserted_here_p (aspace
,
4268 tp
->suspend
.stop_reason
4269 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4271 else if (!thread_has_single_step_breakpoints_set (tp
)
4272 && currently_stepping (tp
))
4274 tp
->suspend
.stop_reason
4275 = TARGET_STOPPED_BY_SINGLE_STEP
;
4283 stop_all_threads (void)
4285 /* We may need multiple passes to discover all threads. */
4289 gdb_assert (target_is_non_stop_p ());
4292 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads\n");
4294 scoped_restore_current_thread restore_thread
;
4296 target_thread_events (1);
4297 SCOPE_EXIT
{ target_thread_events (0); };
4299 /* Request threads to stop, and then wait for the stops. Because
4300 threads we already know about can spawn more threads while we're
4301 trying to stop them, and we only learn about new threads when we
4302 update the thread list, do this in a loop, and keep iterating
4303 until two passes find no threads that need to be stopped. */
4304 for (pass
= 0; pass
< 2; pass
++, iterations
++)
4307 fprintf_unfiltered (gdb_stdlog
,
4308 "infrun: stop_all_threads, pass=%d, "
4309 "iterations=%d\n", pass
, iterations
);
4313 struct target_waitstatus ws
;
4316 update_thread_list ();
4318 /* Go through all threads looking for threads that we need
4319 to tell the target to stop. */
4320 for (thread_info
*t
: all_non_exited_threads ())
4324 /* If already stopping, don't request a stop again.
4325 We just haven't seen the notification yet. */
4326 if (!t
->stop_requested
)
4329 fprintf_unfiltered (gdb_stdlog
,
4330 "infrun: %s executing, "
4332 target_pid_to_str (t
->ptid
).c_str ());
4333 target_stop (t
->ptid
);
4334 t
->stop_requested
= 1;
4339 fprintf_unfiltered (gdb_stdlog
,
4340 "infrun: %s executing, "
4341 "already stopping\n",
4342 target_pid_to_str (t
->ptid
).c_str ());
4345 if (t
->stop_requested
)
4351 fprintf_unfiltered (gdb_stdlog
,
4352 "infrun: %s not executing\n",
4353 target_pid_to_str (t
->ptid
).c_str ());
4355 /* The thread may be not executing, but still be
4356 resumed with a pending status to process. */
4364 /* If we find new threads on the second iteration, restart
4365 over. We want to see two iterations in a row with all
4370 event_ptid
= wait_one (&ws
);
4373 fprintf_unfiltered (gdb_stdlog
,
4374 "infrun: stop_all_threads %s %s\n",
4375 target_waitstatus_to_string (&ws
).c_str (),
4376 target_pid_to_str (event_ptid
).c_str ());
4379 if (ws
.kind
== TARGET_WAITKIND_NO_RESUMED
4380 || ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
4381 || ws
.kind
== TARGET_WAITKIND_EXITED
4382 || ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
4384 /* All resumed threads exited
4385 or one thread/process exited/signalled. */
4389 thread_info
*t
= find_thread_ptid (event_ptid
);
4391 t
= add_thread (event_ptid
);
4393 t
->stop_requested
= 0;
4396 t
->control
.may_range_step
= 0;
4398 /* This may be the first time we see the inferior report
4400 inferior
*inf
= find_inferior_ptid (event_ptid
);
4401 if (inf
->needs_setup
)
4403 switch_to_thread_no_regs (t
);
4407 if (ws
.kind
== TARGET_WAITKIND_STOPPED
4408 && ws
.value
.sig
== GDB_SIGNAL_0
)
4410 /* We caught the event that we intended to catch, so
4411 there's no event pending. */
4412 t
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
4413 t
->suspend
.waitstatus_pending_p
= 0;
4415 if (displaced_step_fixup (t
, GDB_SIGNAL_0
) < 0)
4417 /* Add it back to the step-over queue. */
4420 fprintf_unfiltered (gdb_stdlog
,
4421 "infrun: displaced-step of %s "
4422 "canceled: adding back to the "
4423 "step-over queue\n",
4424 target_pid_to_str (t
->ptid
).c_str ());
4426 t
->control
.trap_expected
= 0;
4427 thread_step_over_chain_enqueue (t
);
4432 enum gdb_signal sig
;
4433 struct regcache
*regcache
;
4437 std::string statstr
= target_waitstatus_to_string (&ws
);
4439 fprintf_unfiltered (gdb_stdlog
,
4440 "infrun: target_wait %s, saving "
4441 "status for %d.%ld.%ld\n",
4448 /* Record for later. */
4449 save_waitstatus (t
, &ws
);
4451 sig
= (ws
.kind
== TARGET_WAITKIND_STOPPED
4452 ? ws
.value
.sig
: GDB_SIGNAL_0
);
4454 if (displaced_step_fixup (t
, sig
) < 0)
4456 /* Add it back to the step-over queue. */
4457 t
->control
.trap_expected
= 0;
4458 thread_step_over_chain_enqueue (t
);
4461 regcache
= get_thread_regcache (t
);
4462 t
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4466 fprintf_unfiltered (gdb_stdlog
,
4467 "infrun: saved stop_pc=%s for %s "
4468 "(currently_stepping=%d)\n",
4469 paddress (target_gdbarch (),
4470 t
->suspend
.stop_pc
),
4471 target_pid_to_str (t
->ptid
).c_str (),
4472 currently_stepping (t
));
4480 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads done\n");
4483 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
4486 handle_no_resumed (struct execution_control_state
*ecs
)
4488 if (target_can_async_p ())
4495 if (ui
->prompt_state
== PROMPT_BLOCKED
)
4503 /* There were no unwaited-for children left in the target, but,
4504 we're not synchronously waiting for events either. Just
4508 fprintf_unfiltered (gdb_stdlog
,
4509 "infrun: TARGET_WAITKIND_NO_RESUMED "
4510 "(ignoring: bg)\n");
4511 prepare_to_wait (ecs
);
4516 /* Otherwise, if we were running a synchronous execution command, we
4517 may need to cancel it and give the user back the terminal.
4519 In non-stop mode, the target can't tell whether we've already
4520 consumed previous stop events, so it can end up sending us a
4521 no-resumed event like so:
4523 #0 - thread 1 is left stopped
4525 #1 - thread 2 is resumed and hits breakpoint
4526 -> TARGET_WAITKIND_STOPPED
4528 #2 - thread 3 is resumed and exits
4529 this is the last resumed thread, so
4530 -> TARGET_WAITKIND_NO_RESUMED
4532 #3 - gdb processes stop for thread 2 and decides to re-resume
4535 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
4536 thread 2 is now resumed, so the event should be ignored.
4538 IOW, if the stop for thread 2 doesn't end a foreground command,
4539 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
4540 event. But it could be that the event meant that thread 2 itself
4541 (or whatever other thread was the last resumed thread) exited.
4543 To address this we refresh the thread list and check whether we
4544 have resumed threads _now_. In the example above, this removes
4545 thread 3 from the thread list. If thread 2 was re-resumed, we
4546 ignore this event. If we find no thread resumed, then we cancel
4547 the synchronous command show "no unwaited-for " to the user. */
4548 update_thread_list ();
4550 for (thread_info
*thread
: all_non_exited_threads ())
4552 if (thread
->executing
4553 || thread
->suspend
.waitstatus_pending_p
)
4555 /* There were no unwaited-for children left in the target at
4556 some point, but there are now. Just ignore. */
4558 fprintf_unfiltered (gdb_stdlog
,
4559 "infrun: TARGET_WAITKIND_NO_RESUMED "
4560 "(ignoring: found resumed)\n");
4561 prepare_to_wait (ecs
);
4566 /* Note however that we may find no resumed thread because the whole
4567 process exited meanwhile (thus updating the thread list results
4568 in an empty thread list). In this case we know we'll be getting
4569 a process exit event shortly. */
4570 for (inferior
*inf
: all_inferiors ())
4575 thread_info
*thread
= any_live_thread_of_inferior (inf
);
4579 fprintf_unfiltered (gdb_stdlog
,
4580 "infrun: TARGET_WAITKIND_NO_RESUMED "
4581 "(expect process exit)\n");
4582 prepare_to_wait (ecs
);
4587 /* Go ahead and report the event. */
4591 /* Given an execution control state that has been freshly filled in by
4592 an event from the inferior, figure out what it means and take
4595 The alternatives are:
4597 1) stop_waiting and return; to really stop and return to the
4600 2) keep_going and return; to wait for the next event (set
4601 ecs->event_thread->stepping_over_breakpoint to 1 to single step
4605 handle_inferior_event (struct execution_control_state
*ecs
)
4607 /* Make sure that all temporary struct value objects that were
4608 created during the handling of the event get deleted at the
4610 scoped_value_mark free_values
;
4612 enum stop_kind stop_soon
;
4615 fprintf_unfiltered (gdb_stdlog
, "infrun: handle_inferior_event %s\n",
4616 target_waitstatus_to_string (&ecs
->ws
).c_str ());
4618 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
4620 /* We had an event in the inferior, but we are not interested in
4621 handling it at this level. The lower layers have already
4622 done what needs to be done, if anything.
4624 One of the possible circumstances for this is when the
4625 inferior produces output for the console. The inferior has
4626 not stopped, and we are ignoring the event. Another possible
4627 circumstance is any event which the lower level knows will be
4628 reported multiple times without an intervening resume. */
4629 prepare_to_wait (ecs
);
4633 if (ecs
->ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
)
4635 prepare_to_wait (ecs
);
4639 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
4640 && handle_no_resumed (ecs
))
4643 /* Cache the last pid/waitstatus. */
4644 set_last_target_status (ecs
->ptid
, ecs
->ws
);
4646 /* Always clear state belonging to the previous time we stopped. */
4647 stop_stack_dummy
= STOP_NONE
;
4649 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4651 /* No unwaited-for children left. IOW, all resumed children
4653 stop_print_frame
= 0;
4658 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
4659 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
4661 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
4662 /* If it's a new thread, add it to the thread database. */
4663 if (ecs
->event_thread
== NULL
)
4664 ecs
->event_thread
= add_thread (ecs
->ptid
);
4666 /* Disable range stepping. If the next step request could use a
4667 range, this will be end up re-enabled then. */
4668 ecs
->event_thread
->control
.may_range_step
= 0;
4671 /* Dependent on valid ECS->EVENT_THREAD. */
4672 adjust_pc_after_break (ecs
->event_thread
, &ecs
->ws
);
4674 /* Dependent on the current PC value modified by adjust_pc_after_break. */
4675 reinit_frame_cache ();
4677 breakpoint_retire_moribund ();
4679 /* First, distinguish signals caused by the debugger from signals
4680 that have to do with the program's own actions. Note that
4681 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
4682 on the operating system version. Here we detect when a SIGILL or
4683 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
4684 something similar for SIGSEGV, since a SIGSEGV will be generated
4685 when we're trying to execute a breakpoint instruction on a
4686 non-executable stack. This happens for call dummy breakpoints
4687 for architectures like SPARC that place call dummies on the
4689 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
4690 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
4691 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
4692 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
4694 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
4696 if (breakpoint_inserted_here_p (regcache
->aspace (),
4697 regcache_read_pc (regcache
)))
4700 fprintf_unfiltered (gdb_stdlog
,
4701 "infrun: Treating signal as SIGTRAP\n");
4702 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
4706 /* Mark the non-executing threads accordingly. In all-stop, all
4707 threads of all processes are stopped when we get any event
4708 reported. In non-stop mode, only the event thread stops. */
4712 if (!target_is_non_stop_p ())
4713 mark_ptid
= minus_one_ptid
;
4714 else if (ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
4715 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4717 /* If we're handling a process exit in non-stop mode, even
4718 though threads haven't been deleted yet, one would think
4719 that there is nothing to do, as threads of the dead process
4720 will be soon deleted, and threads of any other process were
4721 left running. However, on some targets, threads survive a
4722 process exit event. E.g., for the "checkpoint" command,
4723 when the current checkpoint/fork exits, linux-fork.c
4724 automatically switches to another fork from within
4725 target_mourn_inferior, by associating the same
4726 inferior/thread to another fork. We haven't mourned yet at
4727 this point, but we must mark any threads left in the
4728 process as not-executing so that finish_thread_state marks
4729 them stopped (in the user's perspective) if/when we present
4730 the stop to the user. */
4731 mark_ptid
= ptid_t (ecs
->ptid
.pid ());
4734 mark_ptid
= ecs
->ptid
;
4736 set_executing (mark_ptid
, 0);
4738 /* Likewise the resumed flag. */
4739 set_resumed (mark_ptid
, 0);
4742 switch (ecs
->ws
.kind
)
4744 case TARGET_WAITKIND_LOADED
:
4745 context_switch (ecs
);
4746 /* Ignore gracefully during startup of the inferior, as it might
4747 be the shell which has just loaded some objects, otherwise
4748 add the symbols for the newly loaded objects. Also ignore at
4749 the beginning of an attach or remote session; we will query
4750 the full list of libraries once the connection is
4753 stop_soon
= get_inferior_stop_soon (ecs
);
4754 if (stop_soon
== NO_STOP_QUIETLY
)
4756 struct regcache
*regcache
;
4758 regcache
= get_thread_regcache (ecs
->event_thread
);
4760 handle_solib_event ();
4762 ecs
->event_thread
->control
.stop_bpstat
4763 = bpstat_stop_status (regcache
->aspace (),
4764 ecs
->event_thread
->suspend
.stop_pc
,
4765 ecs
->event_thread
, &ecs
->ws
);
4767 if (handle_stop_requested (ecs
))
4770 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4772 /* A catchpoint triggered. */
4773 process_event_stop_test (ecs
);
4777 /* If requested, stop when the dynamic linker notifies
4778 gdb of events. This allows the user to get control
4779 and place breakpoints in initializer routines for
4780 dynamically loaded objects (among other things). */
4781 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4782 if (stop_on_solib_events
)
4784 /* Make sure we print "Stopped due to solib-event" in
4786 stop_print_frame
= 1;
4793 /* If we are skipping through a shell, or through shared library
4794 loading that we aren't interested in, resume the program. If
4795 we're running the program normally, also resume. */
4796 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
4798 /* Loading of shared libraries might have changed breakpoint
4799 addresses. Make sure new breakpoints are inserted. */
4800 if (stop_soon
== NO_STOP_QUIETLY
)
4801 insert_breakpoints ();
4802 resume (GDB_SIGNAL_0
);
4803 prepare_to_wait (ecs
);
4807 /* But stop if we're attaching or setting up a remote
4809 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4810 || stop_soon
== STOP_QUIETLY_REMOTE
)
4813 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
4818 internal_error (__FILE__
, __LINE__
,
4819 _("unhandled stop_soon: %d"), (int) stop_soon
);
4821 case TARGET_WAITKIND_SPURIOUS
:
4822 if (handle_stop_requested (ecs
))
4824 context_switch (ecs
);
4825 resume (GDB_SIGNAL_0
);
4826 prepare_to_wait (ecs
);
4829 case TARGET_WAITKIND_THREAD_CREATED
:
4830 if (handle_stop_requested (ecs
))
4832 context_switch (ecs
);
4833 if (!switch_back_to_stepped_thread (ecs
))
4837 case TARGET_WAITKIND_EXITED
:
4838 case TARGET_WAITKIND_SIGNALLED
:
4839 inferior_ptid
= ecs
->ptid
;
4840 set_current_inferior (find_inferior_ptid (ecs
->ptid
));
4841 set_current_program_space (current_inferior ()->pspace
);
4842 handle_vfork_child_exec_or_exit (0);
4843 target_terminal::ours (); /* Must do this before mourn anyway. */
4845 /* Clearing any previous state of convenience variables. */
4846 clear_exit_convenience_vars ();
4848 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4850 /* Record the exit code in the convenience variable $_exitcode, so
4851 that the user can inspect this again later. */
4852 set_internalvar_integer (lookup_internalvar ("_exitcode"),
4853 (LONGEST
) ecs
->ws
.value
.integer
);
4855 /* Also record this in the inferior itself. */
4856 current_inferior ()->has_exit_code
= 1;
4857 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
4859 /* Support the --return-child-result option. */
4860 return_child_result_value
= ecs
->ws
.value
.integer
;
4862 gdb::observers::exited
.notify (ecs
->ws
.value
.integer
);
4866 struct gdbarch
*gdbarch
= current_inferior ()->gdbarch
;
4868 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
4870 /* Set the value of the internal variable $_exitsignal,
4871 which holds the signal uncaught by the inferior. */
4872 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
4873 gdbarch_gdb_signal_to_target (gdbarch
,
4874 ecs
->ws
.value
.sig
));
4878 /* We don't have access to the target's method used for
4879 converting between signal numbers (GDB's internal
4880 representation <-> target's representation).
4881 Therefore, we cannot do a good job at displaying this
4882 information to the user. It's better to just warn
4883 her about it (if infrun debugging is enabled), and
4886 fprintf_filtered (gdb_stdlog
, _("\
4887 Cannot fill $_exitsignal with the correct signal number.\n"));
4890 gdb::observers::signal_exited
.notify (ecs
->ws
.value
.sig
);
4893 gdb_flush (gdb_stdout
);
4894 target_mourn_inferior (inferior_ptid
);
4895 stop_print_frame
= 0;
4899 /* The following are the only cases in which we keep going;
4900 the above cases end in a continue or goto. */
4901 case TARGET_WAITKIND_FORKED
:
4902 case TARGET_WAITKIND_VFORKED
:
4903 /* Check whether the inferior is displaced stepping. */
4905 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
4906 struct gdbarch
*gdbarch
= regcache
->arch ();
4908 /* If checking displaced stepping is supported, and thread
4909 ecs->ptid is displaced stepping. */
4910 if (displaced_step_in_progress_thread (ecs
->event_thread
))
4912 struct inferior
*parent_inf
4913 = find_inferior_ptid (ecs
->ptid
);
4914 struct regcache
*child_regcache
;
4915 CORE_ADDR parent_pc
;
4917 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
4918 indicating that the displaced stepping of syscall instruction
4919 has been done. Perform cleanup for parent process here. Note
4920 that this operation also cleans up the child process for vfork,
4921 because their pages are shared. */
4922 displaced_step_fixup (ecs
->event_thread
, GDB_SIGNAL_TRAP
);
4923 /* Start a new step-over in another thread if there's one
4927 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
4929 struct displaced_step_inferior_state
*displaced
4930 = get_displaced_stepping_state (parent_inf
);
4932 /* Restore scratch pad for child process. */
4933 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
4936 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
4937 the child's PC is also within the scratchpad. Set the child's PC
4938 to the parent's PC value, which has already been fixed up.
4939 FIXME: we use the parent's aspace here, although we're touching
4940 the child, because the child hasn't been added to the inferior
4941 list yet at this point. */
4944 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
4946 parent_inf
->aspace
);
4947 /* Read PC value of parent process. */
4948 parent_pc
= regcache_read_pc (regcache
);
4950 if (debug_displaced
)
4951 fprintf_unfiltered (gdb_stdlog
,
4952 "displaced: write child pc from %s to %s\n",
4954 regcache_read_pc (child_regcache
)),
4955 paddress (gdbarch
, parent_pc
));
4957 regcache_write_pc (child_regcache
, parent_pc
);
4961 context_switch (ecs
);
4963 /* Immediately detach breakpoints from the child before there's
4964 any chance of letting the user delete breakpoints from the
4965 breakpoint lists. If we don't do this early, it's easy to
4966 leave left over traps in the child, vis: "break foo; catch
4967 fork; c; <fork>; del; c; <child calls foo>". We only follow
4968 the fork on the last `continue', and by that time the
4969 breakpoint at "foo" is long gone from the breakpoint table.
4970 If we vforked, then we don't need to unpatch here, since both
4971 parent and child are sharing the same memory pages; we'll
4972 need to unpatch at follow/detach time instead to be certain
4973 that new breakpoints added between catchpoint hit time and
4974 vfork follow are detached. */
4975 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
4977 /* This won't actually modify the breakpoint list, but will
4978 physically remove the breakpoints from the child. */
4979 detach_breakpoints (ecs
->ws
.value
.related_pid
);
4982 delete_just_stopped_threads_single_step_breakpoints ();
4984 /* In case the event is caught by a catchpoint, remember that
4985 the event is to be followed at the next resume of the thread,
4986 and not immediately. */
4987 ecs
->event_thread
->pending_follow
= ecs
->ws
;
4989 ecs
->event_thread
->suspend
.stop_pc
4990 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
4992 ecs
->event_thread
->control
.stop_bpstat
4993 = bpstat_stop_status (get_current_regcache ()->aspace (),
4994 ecs
->event_thread
->suspend
.stop_pc
,
4995 ecs
->event_thread
, &ecs
->ws
);
4997 if (handle_stop_requested (ecs
))
5000 /* If no catchpoint triggered for this, then keep going. Note
5001 that we're interested in knowing the bpstat actually causes a
5002 stop, not just if it may explain the signal. Software
5003 watchpoints, for example, always appear in the bpstat. */
5004 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5008 = (follow_fork_mode_string
== follow_fork_mode_child
);
5010 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5012 should_resume
= follow_fork ();
5014 thread_info
*parent
= ecs
->event_thread
;
5015 thread_info
*child
= find_thread_ptid (ecs
->ws
.value
.related_pid
);
5017 /* At this point, the parent is marked running, and the
5018 child is marked stopped. */
5020 /* If not resuming the parent, mark it stopped. */
5021 if (follow_child
&& !detach_fork
&& !non_stop
&& !sched_multi
)
5022 parent
->set_running (false);
5024 /* If resuming the child, mark it running. */
5025 if (follow_child
|| (!detach_fork
&& (non_stop
|| sched_multi
)))
5026 child
->set_running (true);
5028 /* In non-stop mode, also resume the other branch. */
5029 if (!detach_fork
&& (non_stop
5030 || (sched_multi
&& target_is_non_stop_p ())))
5033 switch_to_thread (parent
);
5035 switch_to_thread (child
);
5037 ecs
->event_thread
= inferior_thread ();
5038 ecs
->ptid
= inferior_ptid
;
5043 switch_to_thread (child
);
5045 switch_to_thread (parent
);
5047 ecs
->event_thread
= inferior_thread ();
5048 ecs
->ptid
= inferior_ptid
;
5056 process_event_stop_test (ecs
);
5059 case TARGET_WAITKIND_VFORK_DONE
:
5060 /* Done with the shared memory region. Re-insert breakpoints in
5061 the parent, and keep going. */
5063 context_switch (ecs
);
5065 current_inferior ()->waiting_for_vfork_done
= 0;
5066 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
5068 if (handle_stop_requested (ecs
))
5071 /* This also takes care of reinserting breakpoints in the
5072 previously locked inferior. */
5076 case TARGET_WAITKIND_EXECD
:
5078 /* Note we can't read registers yet (the stop_pc), because we
5079 don't yet know the inferior's post-exec architecture.
5080 'stop_pc' is explicitly read below instead. */
5081 switch_to_thread_no_regs (ecs
->event_thread
);
5083 /* Do whatever is necessary to the parent branch of the vfork. */
5084 handle_vfork_child_exec_or_exit (1);
5086 /* This causes the eventpoints and symbol table to be reset.
5087 Must do this now, before trying to determine whether to
5089 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
5091 /* In follow_exec we may have deleted the original thread and
5092 created a new one. Make sure that the event thread is the
5093 execd thread for that case (this is a nop otherwise). */
5094 ecs
->event_thread
= inferior_thread ();
5096 ecs
->event_thread
->suspend
.stop_pc
5097 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
5099 ecs
->event_thread
->control
.stop_bpstat
5100 = bpstat_stop_status (get_current_regcache ()->aspace (),
5101 ecs
->event_thread
->suspend
.stop_pc
,
5102 ecs
->event_thread
, &ecs
->ws
);
5104 /* Note that this may be referenced from inside
5105 bpstat_stop_status above, through inferior_has_execd. */
5106 xfree (ecs
->ws
.value
.execd_pathname
);
5107 ecs
->ws
.value
.execd_pathname
= NULL
;
5109 if (handle_stop_requested (ecs
))
5112 /* If no catchpoint triggered for this, then keep going. */
5113 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5115 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5119 process_event_stop_test (ecs
);
5122 /* Be careful not to try to gather much state about a thread
5123 that's in a syscall. It's frequently a losing proposition. */
5124 case TARGET_WAITKIND_SYSCALL_ENTRY
:
5125 /* Getting the current syscall number. */
5126 if (handle_syscall_event (ecs
) == 0)
5127 process_event_stop_test (ecs
);
5130 /* Before examining the threads further, step this thread to
5131 get it entirely out of the syscall. (We get notice of the
5132 event when the thread is just on the verge of exiting a
5133 syscall. Stepping one instruction seems to get it back
5135 case TARGET_WAITKIND_SYSCALL_RETURN
:
5136 if (handle_syscall_event (ecs
) == 0)
5137 process_event_stop_test (ecs
);
5140 case TARGET_WAITKIND_STOPPED
:
5141 handle_signal_stop (ecs
);
5144 case TARGET_WAITKIND_NO_HISTORY
:
5145 /* Reverse execution: target ran out of history info. */
5147 /* Switch to the stopped thread. */
5148 context_switch (ecs
);
5150 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
5152 delete_just_stopped_threads_single_step_breakpoints ();
5153 ecs
->event_thread
->suspend
.stop_pc
5154 = regcache_read_pc (get_thread_regcache (inferior_thread ()));
5156 if (handle_stop_requested (ecs
))
5159 gdb::observers::no_history
.notify ();
5165 /* Restart threads back to what they were trying to do back when we
5166 paused them for an in-line step-over. The EVENT_THREAD thread is
5170 restart_threads (struct thread_info
*event_thread
)
5172 /* In case the instruction just stepped spawned a new thread. */
5173 update_thread_list ();
5175 for (thread_info
*tp
: all_non_exited_threads ())
5177 if (tp
== event_thread
)
5180 fprintf_unfiltered (gdb_stdlog
,
5181 "infrun: restart threads: "
5182 "[%s] is event thread\n",
5183 target_pid_to_str (tp
->ptid
).c_str ());
5187 if (!(tp
->state
== THREAD_RUNNING
|| tp
->control
.in_infcall
))
5190 fprintf_unfiltered (gdb_stdlog
,
5191 "infrun: restart threads: "
5192 "[%s] not meant to be running\n",
5193 target_pid_to_str (tp
->ptid
).c_str ());
5200 fprintf_unfiltered (gdb_stdlog
,
5201 "infrun: restart threads: [%s] resumed\n",
5202 target_pid_to_str (tp
->ptid
).c_str ());
5203 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
5207 if (thread_is_in_step_over_chain (tp
))
5210 fprintf_unfiltered (gdb_stdlog
,
5211 "infrun: restart threads: "
5212 "[%s] needs step-over\n",
5213 target_pid_to_str (tp
->ptid
).c_str ());
5214 gdb_assert (!tp
->resumed
);
5219 if (tp
->suspend
.waitstatus_pending_p
)
5222 fprintf_unfiltered (gdb_stdlog
,
5223 "infrun: restart threads: "
5224 "[%s] has pending status\n",
5225 target_pid_to_str (tp
->ptid
).c_str ());
5230 gdb_assert (!tp
->stop_requested
);
5232 /* If some thread needs to start a step-over at this point, it
5233 should still be in the step-over queue, and thus skipped
5235 if (thread_still_needs_step_over (tp
))
5237 internal_error (__FILE__
, __LINE__
,
5238 "thread [%s] needs a step-over, but not in "
5239 "step-over queue\n",
5240 target_pid_to_str (tp
->ptid
).c_str ());
5243 if (currently_stepping (tp
))
5246 fprintf_unfiltered (gdb_stdlog
,
5247 "infrun: restart threads: [%s] was stepping\n",
5248 target_pid_to_str (tp
->ptid
).c_str ());
5249 keep_going_stepped_thread (tp
);
5253 struct execution_control_state ecss
;
5254 struct execution_control_state
*ecs
= &ecss
;
5257 fprintf_unfiltered (gdb_stdlog
,
5258 "infrun: restart threads: [%s] continuing\n",
5259 target_pid_to_str (tp
->ptid
).c_str ());
5260 reset_ecs (ecs
, tp
);
5261 switch_to_thread (tp
);
5262 keep_going_pass_signal (ecs
);
5267 /* Callback for iterate_over_threads. Find a resumed thread that has
5268 a pending waitstatus. */
5271 resumed_thread_with_pending_status (struct thread_info
*tp
,
5275 && tp
->suspend
.waitstatus_pending_p
);
5278 /* Called when we get an event that may finish an in-line or
5279 out-of-line (displaced stepping) step-over started previously.
5280 Return true if the event is processed and we should go back to the
5281 event loop; false if the caller should continue processing the
5285 finish_step_over (struct execution_control_state
*ecs
)
5287 int had_step_over_info
;
5289 displaced_step_fixup (ecs
->event_thread
,
5290 ecs
->event_thread
->suspend
.stop_signal
);
5292 had_step_over_info
= step_over_info_valid_p ();
5294 if (had_step_over_info
)
5296 /* If we're stepping over a breakpoint with all threads locked,
5297 then only the thread that was stepped should be reporting
5299 gdb_assert (ecs
->event_thread
->control
.trap_expected
);
5301 clear_step_over_info ();
5304 if (!target_is_non_stop_p ())
5307 /* Start a new step-over in another thread if there's one that
5311 /* If we were stepping over a breakpoint before, and haven't started
5312 a new in-line step-over sequence, then restart all other threads
5313 (except the event thread). We can't do this in all-stop, as then
5314 e.g., we wouldn't be able to issue any other remote packet until
5315 these other threads stop. */
5316 if (had_step_over_info
&& !step_over_info_valid_p ())
5318 struct thread_info
*pending
;
5320 /* If we only have threads with pending statuses, the restart
5321 below won't restart any thread and so nothing re-inserts the
5322 breakpoint we just stepped over. But we need it inserted
5323 when we later process the pending events, otherwise if
5324 another thread has a pending event for this breakpoint too,
5325 we'd discard its event (because the breakpoint that
5326 originally caused the event was no longer inserted). */
5327 context_switch (ecs
);
5328 insert_breakpoints ();
5330 restart_threads (ecs
->event_thread
);
5332 /* If we have events pending, go through handle_inferior_event
5333 again, picking up a pending event at random. This avoids
5334 thread starvation. */
5336 /* But not if we just stepped over a watchpoint in order to let
5337 the instruction execute so we can evaluate its expression.
5338 The set of watchpoints that triggered is recorded in the
5339 breakpoint objects themselves (see bp->watchpoint_triggered).
5340 If we processed another event first, that other event could
5341 clobber this info. */
5342 if (ecs
->event_thread
->stepping_over_watchpoint
)
5345 pending
= iterate_over_threads (resumed_thread_with_pending_status
,
5347 if (pending
!= NULL
)
5349 struct thread_info
*tp
= ecs
->event_thread
;
5350 struct regcache
*regcache
;
5354 fprintf_unfiltered (gdb_stdlog
,
5355 "infrun: found resumed threads with "
5356 "pending events, saving status\n");
5359 gdb_assert (pending
!= tp
);
5361 /* Record the event thread's event for later. */
5362 save_waitstatus (tp
, &ecs
->ws
);
5363 /* This was cleared early, by handle_inferior_event. Set it
5364 so this pending event is considered by
5368 gdb_assert (!tp
->executing
);
5370 regcache
= get_thread_regcache (tp
);
5371 tp
->suspend
.stop_pc
= regcache_read_pc (regcache
);
5375 fprintf_unfiltered (gdb_stdlog
,
5376 "infrun: saved stop_pc=%s for %s "
5377 "(currently_stepping=%d)\n",
5378 paddress (target_gdbarch (),
5379 tp
->suspend
.stop_pc
),
5380 target_pid_to_str (tp
->ptid
).c_str (),
5381 currently_stepping (tp
));
5384 /* This in-line step-over finished; clear this so we won't
5385 start a new one. This is what handle_signal_stop would
5386 do, if we returned false. */
5387 tp
->stepping_over_breakpoint
= 0;
5389 /* Wake up the event loop again. */
5390 mark_async_event_handler (infrun_async_inferior_event_token
);
5392 prepare_to_wait (ecs
);
5400 /* Come here when the program has stopped with a signal. */
5403 handle_signal_stop (struct execution_control_state
*ecs
)
5405 struct frame_info
*frame
;
5406 struct gdbarch
*gdbarch
;
5407 int stopped_by_watchpoint
;
5408 enum stop_kind stop_soon
;
5411 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
5413 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
5415 /* Do we need to clean up the state of a thread that has
5416 completed a displaced single-step? (Doing so usually affects
5417 the PC, so do it here, before we set stop_pc.) */
5418 if (finish_step_over (ecs
))
5421 /* If we either finished a single-step or hit a breakpoint, but
5422 the user wanted this thread to be stopped, pretend we got a
5423 SIG0 (generic unsignaled stop). */
5424 if (ecs
->event_thread
->stop_requested
5425 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5426 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5428 ecs
->event_thread
->suspend
.stop_pc
5429 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
5433 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
5434 struct gdbarch
*reg_gdbarch
= regcache
->arch ();
5435 scoped_restore save_inferior_ptid
= make_scoped_restore (&inferior_ptid
);
5437 inferior_ptid
= ecs
->ptid
;
5439 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
5440 paddress (reg_gdbarch
,
5441 ecs
->event_thread
->suspend
.stop_pc
));
5442 if (target_stopped_by_watchpoint ())
5446 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
5448 if (target_stopped_data_address (current_top_target (), &addr
))
5449 fprintf_unfiltered (gdb_stdlog
,
5450 "infrun: stopped data address = %s\n",
5451 paddress (reg_gdbarch
, addr
));
5453 fprintf_unfiltered (gdb_stdlog
,
5454 "infrun: (no data address available)\n");
5458 /* This is originated from start_remote(), start_inferior() and
5459 shared libraries hook functions. */
5460 stop_soon
= get_inferior_stop_soon (ecs
);
5461 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
5463 context_switch (ecs
);
5465 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5466 stop_print_frame
= 1;
5471 /* This originates from attach_command(). We need to overwrite
5472 the stop_signal here, because some kernels don't ignore a
5473 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5474 See more comments in inferior.h. On the other hand, if we
5475 get a non-SIGSTOP, report it to the user - assume the backend
5476 will handle the SIGSTOP if it should show up later.
5478 Also consider that the attach is complete when we see a
5479 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5480 target extended-remote report it instead of a SIGSTOP
5481 (e.g. gdbserver). We already rely on SIGTRAP being our
5482 signal, so this is no exception.
5484 Also consider that the attach is complete when we see a
5485 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5486 the target to stop all threads of the inferior, in case the
5487 low level attach operation doesn't stop them implicitly. If
5488 they weren't stopped implicitly, then the stub will report a
5489 GDB_SIGNAL_0, meaning: stopped for no particular reason
5490 other than GDB's request. */
5491 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5492 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
5493 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5494 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
5496 stop_print_frame
= 1;
5498 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5502 /* See if something interesting happened to the non-current thread. If
5503 so, then switch to that thread. */
5504 if (ecs
->ptid
!= inferior_ptid
)
5507 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
5509 context_switch (ecs
);
5511 if (deprecated_context_hook
)
5512 deprecated_context_hook (ecs
->event_thread
->global_num
);
5515 /* At this point, get hold of the now-current thread's frame. */
5516 frame
= get_current_frame ();
5517 gdbarch
= get_frame_arch (frame
);
5519 /* Pull the single step breakpoints out of the target. */
5520 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5522 struct regcache
*regcache
;
5525 regcache
= get_thread_regcache (ecs
->event_thread
);
5526 const address_space
*aspace
= regcache
->aspace ();
5528 pc
= regcache_read_pc (regcache
);
5530 /* However, before doing so, if this single-step breakpoint was
5531 actually for another thread, set this thread up for moving
5533 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
5536 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
5540 fprintf_unfiltered (gdb_stdlog
,
5541 "infrun: [%s] hit another thread's "
5542 "single-step breakpoint\n",
5543 target_pid_to_str (ecs
->ptid
).c_str ());
5545 ecs
->hit_singlestep_breakpoint
= 1;
5552 fprintf_unfiltered (gdb_stdlog
,
5553 "infrun: [%s] hit its "
5554 "single-step breakpoint\n",
5555 target_pid_to_str (ecs
->ptid
).c_str ());
5559 delete_just_stopped_threads_single_step_breakpoints ();
5561 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5562 && ecs
->event_thread
->control
.trap_expected
5563 && ecs
->event_thread
->stepping_over_watchpoint
)
5564 stopped_by_watchpoint
= 0;
5566 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
5568 /* If necessary, step over this watchpoint. We'll be back to display
5570 if (stopped_by_watchpoint
5571 && (target_have_steppable_watchpoint
5572 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
5574 /* At this point, we are stopped at an instruction which has
5575 attempted to write to a piece of memory under control of
5576 a watchpoint. The instruction hasn't actually executed
5577 yet. If we were to evaluate the watchpoint expression
5578 now, we would get the old value, and therefore no change
5579 would seem to have occurred.
5581 In order to make watchpoints work `right', we really need
5582 to complete the memory write, and then evaluate the
5583 watchpoint expression. We do this by single-stepping the
5586 It may not be necessary to disable the watchpoint to step over
5587 it. For example, the PA can (with some kernel cooperation)
5588 single step over a watchpoint without disabling the watchpoint.
5590 It is far more common to need to disable a watchpoint to step
5591 the inferior over it. If we have non-steppable watchpoints,
5592 we must disable the current watchpoint; it's simplest to
5593 disable all watchpoints.
5595 Any breakpoint at PC must also be stepped over -- if there's
5596 one, it will have already triggered before the watchpoint
5597 triggered, and we either already reported it to the user, or
5598 it didn't cause a stop and we called keep_going. In either
5599 case, if there was a breakpoint at PC, we must be trying to
5601 ecs
->event_thread
->stepping_over_watchpoint
= 1;
5606 ecs
->event_thread
->stepping_over_breakpoint
= 0;
5607 ecs
->event_thread
->stepping_over_watchpoint
= 0;
5608 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
5609 ecs
->event_thread
->control
.stop_step
= 0;
5610 stop_print_frame
= 1;
5611 stopped_by_random_signal
= 0;
5612 bpstat stop_chain
= NULL
;
5614 /* Hide inlined functions starting here, unless we just performed stepi or
5615 nexti. After stepi and nexti, always show the innermost frame (not any
5616 inline function call sites). */
5617 if (ecs
->event_thread
->control
.step_range_end
!= 1)
5619 const address_space
*aspace
5620 = get_thread_regcache (ecs
->event_thread
)->aspace ();
5622 /* skip_inline_frames is expensive, so we avoid it if we can
5623 determine that the address is one where functions cannot have
5624 been inlined. This improves performance with inferiors that
5625 load a lot of shared libraries, because the solib event
5626 breakpoint is defined as the address of a function (i.e. not
5627 inline). Note that we have to check the previous PC as well
5628 as the current one to catch cases when we have just
5629 single-stepped off a breakpoint prior to reinstating it.
5630 Note that we're assuming that the code we single-step to is
5631 not inline, but that's not definitive: there's nothing
5632 preventing the event breakpoint function from containing
5633 inlined code, and the single-step ending up there. If the
5634 user had set a breakpoint on that inlined code, the missing
5635 skip_inline_frames call would break things. Fortunately
5636 that's an extremely unlikely scenario. */
5637 if (!pc_at_non_inline_function (aspace
,
5638 ecs
->event_thread
->suspend
.stop_pc
,
5640 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5641 && ecs
->event_thread
->control
.trap_expected
5642 && pc_at_non_inline_function (aspace
,
5643 ecs
->event_thread
->prev_pc
,
5646 stop_chain
= build_bpstat_chain (aspace
,
5647 ecs
->event_thread
->suspend
.stop_pc
,
5649 skip_inline_frames (ecs
->event_thread
, stop_chain
);
5651 /* Re-fetch current thread's frame in case that invalidated
5653 frame
= get_current_frame ();
5654 gdbarch
= get_frame_arch (frame
);
5658 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5659 && ecs
->event_thread
->control
.trap_expected
5660 && gdbarch_single_step_through_delay_p (gdbarch
)
5661 && currently_stepping (ecs
->event_thread
))
5663 /* We're trying to step off a breakpoint. Turns out that we're
5664 also on an instruction that needs to be stepped multiple
5665 times before it's been fully executing. E.g., architectures
5666 with a delay slot. It needs to be stepped twice, once for
5667 the instruction and once for the delay slot. */
5668 int step_through_delay
5669 = gdbarch_single_step_through_delay (gdbarch
, frame
);
5671 if (debug_infrun
&& step_through_delay
)
5672 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
5673 if (ecs
->event_thread
->control
.step_range_end
== 0
5674 && step_through_delay
)
5676 /* The user issued a continue when stopped at a breakpoint.
5677 Set up for another trap and get out of here. */
5678 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5682 else if (step_through_delay
)
5684 /* The user issued a step when stopped at a breakpoint.
5685 Maybe we should stop, maybe we should not - the delay
5686 slot *might* correspond to a line of source. In any
5687 case, don't decide that here, just set
5688 ecs->stepping_over_breakpoint, making sure we
5689 single-step again before breakpoints are re-inserted. */
5690 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5694 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
5695 handles this event. */
5696 ecs
->event_thread
->control
.stop_bpstat
5697 = bpstat_stop_status (get_current_regcache ()->aspace (),
5698 ecs
->event_thread
->suspend
.stop_pc
,
5699 ecs
->event_thread
, &ecs
->ws
, stop_chain
);
5701 /* Following in case break condition called a
5703 stop_print_frame
= 1;
5705 /* This is where we handle "moribund" watchpoints. Unlike
5706 software breakpoints traps, hardware watchpoint traps are
5707 always distinguishable from random traps. If no high-level
5708 watchpoint is associated with the reported stop data address
5709 anymore, then the bpstat does not explain the signal ---
5710 simply make sure to ignore it if `stopped_by_watchpoint' is
5714 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5715 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5717 && stopped_by_watchpoint
)
5718 fprintf_unfiltered (gdb_stdlog
,
5719 "infrun: no user watchpoint explains "
5720 "watchpoint SIGTRAP, ignoring\n");
5722 /* NOTE: cagney/2003-03-29: These checks for a random signal
5723 at one stage in the past included checks for an inferior
5724 function call's call dummy's return breakpoint. The original
5725 comment, that went with the test, read:
5727 ``End of a stack dummy. Some systems (e.g. Sony news) give
5728 another signal besides SIGTRAP, so check here as well as
5731 If someone ever tries to get call dummys on a
5732 non-executable stack to work (where the target would stop
5733 with something like a SIGSEGV), then those tests might need
5734 to be re-instated. Given, however, that the tests were only
5735 enabled when momentary breakpoints were not being used, I
5736 suspect that it won't be the case.
5738 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
5739 be necessary for call dummies on a non-executable stack on
5742 /* See if the breakpoints module can explain the signal. */
5744 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5745 ecs
->event_thread
->suspend
.stop_signal
);
5747 /* Maybe this was a trap for a software breakpoint that has since
5749 if (random_signal
&& target_stopped_by_sw_breakpoint ())
5751 if (program_breakpoint_here_p (gdbarch
,
5752 ecs
->event_thread
->suspend
.stop_pc
))
5754 struct regcache
*regcache
;
5757 /* Re-adjust PC to what the program would see if GDB was not
5759 regcache
= get_thread_regcache (ecs
->event_thread
);
5760 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
5763 gdb::optional
<scoped_restore_tmpl
<int>>
5764 restore_operation_disable
;
5766 if (record_full_is_used ())
5767 restore_operation_disable
.emplace
5768 (record_full_gdb_operation_disable_set ());
5770 regcache_write_pc (regcache
,
5771 ecs
->event_thread
->suspend
.stop_pc
+ decr_pc
);
5776 /* A delayed software breakpoint event. Ignore the trap. */
5778 fprintf_unfiltered (gdb_stdlog
,
5779 "infrun: delayed software breakpoint "
5780 "trap, ignoring\n");
5785 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
5786 has since been removed. */
5787 if (random_signal
&& target_stopped_by_hw_breakpoint ())
5789 /* A delayed hardware breakpoint event. Ignore the trap. */
5791 fprintf_unfiltered (gdb_stdlog
,
5792 "infrun: delayed hardware breakpoint/watchpoint "
5793 "trap, ignoring\n");
5797 /* If not, perhaps stepping/nexting can. */
5799 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5800 && currently_stepping (ecs
->event_thread
));
5802 /* Perhaps the thread hit a single-step breakpoint of _another_
5803 thread. Single-step breakpoints are transparent to the
5804 breakpoints module. */
5806 random_signal
= !ecs
->hit_singlestep_breakpoint
;
5808 /* No? Perhaps we got a moribund watchpoint. */
5810 random_signal
= !stopped_by_watchpoint
;
5812 /* Always stop if the user explicitly requested this thread to
5814 if (ecs
->event_thread
->stop_requested
)
5818 fprintf_unfiltered (gdb_stdlog
, "infrun: user-requested stop\n");
5821 /* For the program's own signals, act according to
5822 the signal handling tables. */
5826 /* Signal not for debugging purposes. */
5827 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
5828 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
5831 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
5832 gdb_signal_to_symbol_string (stop_signal
));
5834 stopped_by_random_signal
= 1;
5836 /* Always stop on signals if we're either just gaining control
5837 of the program, or the user explicitly requested this thread
5838 to remain stopped. */
5839 if (stop_soon
!= NO_STOP_QUIETLY
5840 || ecs
->event_thread
->stop_requested
5842 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
5848 /* Notify observers the signal has "handle print" set. Note we
5849 returned early above if stopping; normal_stop handles the
5850 printing in that case. */
5851 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
5853 /* The signal table tells us to print about this signal. */
5854 target_terminal::ours_for_output ();
5855 gdb::observers::signal_received
.notify (ecs
->event_thread
->suspend
.stop_signal
);
5856 target_terminal::inferior ();
5859 /* Clear the signal if it should not be passed. */
5860 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
5861 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5863 if (ecs
->event_thread
->prev_pc
== ecs
->event_thread
->suspend
.stop_pc
5864 && ecs
->event_thread
->control
.trap_expected
5865 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
5867 /* We were just starting a new sequence, attempting to
5868 single-step off of a breakpoint and expecting a SIGTRAP.
5869 Instead this signal arrives. This signal will take us out
5870 of the stepping range so GDB needs to remember to, when
5871 the signal handler returns, resume stepping off that
5873 /* To simplify things, "continue" is forced to use the same
5874 code paths as single-step - set a breakpoint at the
5875 signal return address and then, once hit, step off that
5878 fprintf_unfiltered (gdb_stdlog
,
5879 "infrun: signal arrived while stepping over "
5882 insert_hp_step_resume_breakpoint_at_frame (frame
);
5883 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
5884 /* Reset trap_expected to ensure breakpoints are re-inserted. */
5885 ecs
->event_thread
->control
.trap_expected
= 0;
5887 /* If we were nexting/stepping some other thread, switch to
5888 it, so that we don't continue it, losing control. */
5889 if (!switch_back_to_stepped_thread (ecs
))
5894 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
5895 && (pc_in_thread_step_range (ecs
->event_thread
->suspend
.stop_pc
,
5897 || ecs
->event_thread
->control
.step_range_end
== 1)
5898 && frame_id_eq (get_stack_frame_id (frame
),
5899 ecs
->event_thread
->control
.step_stack_frame_id
)
5900 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
5902 /* The inferior is about to take a signal that will take it
5903 out of the single step range. Set a breakpoint at the
5904 current PC (which is presumably where the signal handler
5905 will eventually return) and then allow the inferior to
5908 Note that this is only needed for a signal delivered
5909 while in the single-step range. Nested signals aren't a
5910 problem as they eventually all return. */
5912 fprintf_unfiltered (gdb_stdlog
,
5913 "infrun: signal may take us out of "
5914 "single-step range\n");
5916 clear_step_over_info ();
5917 insert_hp_step_resume_breakpoint_at_frame (frame
);
5918 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
5919 /* Reset trap_expected to ensure breakpoints are re-inserted. */
5920 ecs
->event_thread
->control
.trap_expected
= 0;
5925 /* Note: step_resume_breakpoint may be non-NULL. This occurs
5926 when either there's a nested signal, or when there's a
5927 pending signal enabled just as the signal handler returns
5928 (leaving the inferior at the step-resume-breakpoint without
5929 actually executing it). Either way continue until the
5930 breakpoint is really hit. */
5932 if (!switch_back_to_stepped_thread (ecs
))
5935 fprintf_unfiltered (gdb_stdlog
,
5936 "infrun: random signal, keep going\n");
5943 process_event_stop_test (ecs
);
5946 /* Come here when we've got some debug event / signal we can explain
5947 (IOW, not a random signal), and test whether it should cause a
5948 stop, or whether we should resume the inferior (transparently).
5949 E.g., could be a breakpoint whose condition evaluates false; we
5950 could be still stepping within the line; etc. */
5953 process_event_stop_test (struct execution_control_state
*ecs
)
5955 struct symtab_and_line stop_pc_sal
;
5956 struct frame_info
*frame
;
5957 struct gdbarch
*gdbarch
;
5958 CORE_ADDR jmp_buf_pc
;
5959 struct bpstat_what what
;
5961 /* Handle cases caused by hitting a breakpoint. */
5963 frame
= get_current_frame ();
5964 gdbarch
= get_frame_arch (frame
);
5966 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
5968 if (what
.call_dummy
)
5970 stop_stack_dummy
= what
.call_dummy
;
5973 /* A few breakpoint types have callbacks associated (e.g.,
5974 bp_jit_event). Run them now. */
5975 bpstat_run_callbacks (ecs
->event_thread
->control
.stop_bpstat
);
5977 /* If we hit an internal event that triggers symbol changes, the
5978 current frame will be invalidated within bpstat_what (e.g., if we
5979 hit an internal solib event). Re-fetch it. */
5980 frame
= get_current_frame ();
5981 gdbarch
= get_frame_arch (frame
);
5983 switch (what
.main_action
)
5985 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
5986 /* If we hit the breakpoint at longjmp while stepping, we
5987 install a momentary breakpoint at the target of the
5991 fprintf_unfiltered (gdb_stdlog
,
5992 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
5994 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5996 if (what
.is_longjmp
)
5998 struct value
*arg_value
;
6000 /* If we set the longjmp breakpoint via a SystemTap probe,
6001 then use it to extract the arguments. The destination PC
6002 is the third argument to the probe. */
6003 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
6006 jmp_buf_pc
= value_as_address (arg_value
);
6007 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
6009 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
6010 || !gdbarch_get_longjmp_target (gdbarch
,
6011 frame
, &jmp_buf_pc
))
6014 fprintf_unfiltered (gdb_stdlog
,
6015 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
6016 "(!gdbarch_get_longjmp_target)\n");
6021 /* Insert a breakpoint at resume address. */
6022 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
6025 check_exception_resume (ecs
, frame
);
6029 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
6031 struct frame_info
*init_frame
;
6033 /* There are several cases to consider.
6035 1. The initiating frame no longer exists. In this case we
6036 must stop, because the exception or longjmp has gone too
6039 2. The initiating frame exists, and is the same as the
6040 current frame. We stop, because the exception or longjmp
6043 3. The initiating frame exists and is different from the
6044 current frame. This means the exception or longjmp has
6045 been caught beneath the initiating frame, so keep going.
6047 4. longjmp breakpoint has been placed just to protect
6048 against stale dummy frames and user is not interested in
6049 stopping around longjmps. */
6052 fprintf_unfiltered (gdb_stdlog
,
6053 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
6055 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
6057 delete_exception_resume_breakpoint (ecs
->event_thread
);
6059 if (what
.is_longjmp
)
6061 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
6063 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
6071 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
6075 struct frame_id current_id
6076 = get_frame_id (get_current_frame ());
6077 if (frame_id_eq (current_id
,
6078 ecs
->event_thread
->initiating_frame
))
6080 /* Case 2. Fall through. */
6090 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6092 delete_step_resume_breakpoint (ecs
->event_thread
);
6094 end_stepping_range (ecs
);
6098 case BPSTAT_WHAT_SINGLE
:
6100 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
6101 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6102 /* Still need to check other stuff, at least the case where we
6103 are stepping and step out of the right range. */
6106 case BPSTAT_WHAT_STEP_RESUME
:
6108 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
6110 delete_step_resume_breakpoint (ecs
->event_thread
);
6111 if (ecs
->event_thread
->control
.proceed_to_finish
6112 && execution_direction
== EXEC_REVERSE
)
6114 struct thread_info
*tp
= ecs
->event_thread
;
6116 /* We are finishing a function in reverse, and just hit the
6117 step-resume breakpoint at the start address of the
6118 function, and we're almost there -- just need to back up
6119 by one more single-step, which should take us back to the
6121 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
6125 fill_in_stop_func (gdbarch
, ecs
);
6126 if (ecs
->event_thread
->suspend
.stop_pc
== ecs
->stop_func_start
6127 && execution_direction
== EXEC_REVERSE
)
6129 /* We are stepping over a function call in reverse, and just
6130 hit the step-resume breakpoint at the start address of
6131 the function. Go back to single-stepping, which should
6132 take us back to the function call. */
6133 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6139 case BPSTAT_WHAT_STOP_NOISY
:
6141 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
6142 stop_print_frame
= 1;
6144 /* Assume the thread stopped for a breapoint. We'll still check
6145 whether a/the breakpoint is there when the thread is next
6147 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6152 case BPSTAT_WHAT_STOP_SILENT
:
6154 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
6155 stop_print_frame
= 0;
6157 /* Assume the thread stopped for a breapoint. We'll still check
6158 whether a/the breakpoint is there when the thread is next
6160 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6164 case BPSTAT_WHAT_HP_STEP_RESUME
:
6166 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
6168 delete_step_resume_breakpoint (ecs
->event_thread
);
6169 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
6171 /* Back when the step-resume breakpoint was inserted, we
6172 were trying to single-step off a breakpoint. Go back to
6174 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6175 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6181 case BPSTAT_WHAT_KEEP_CHECKING
:
6185 /* If we stepped a permanent breakpoint and we had a high priority
6186 step-resume breakpoint for the address we stepped, but we didn't
6187 hit it, then we must have stepped into the signal handler. The
6188 step-resume was only necessary to catch the case of _not_
6189 stepping into the handler, so delete it, and fall through to
6190 checking whether the step finished. */
6191 if (ecs
->event_thread
->stepped_breakpoint
)
6193 struct breakpoint
*sr_bp
6194 = ecs
->event_thread
->control
.step_resume_breakpoint
;
6197 && sr_bp
->loc
->permanent
6198 && sr_bp
->type
== bp_hp_step_resume
6199 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
6202 fprintf_unfiltered (gdb_stdlog
,
6203 "infrun: stepped permanent breakpoint, stopped in "
6205 delete_step_resume_breakpoint (ecs
->event_thread
);
6206 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6210 /* We come here if we hit a breakpoint but should not stop for it.
6211 Possibly we also were stepping and should stop for that. So fall
6212 through and test for stepping. But, if not stepping, do not
6215 /* In all-stop mode, if we're currently stepping but have stopped in
6216 some other thread, we need to switch back to the stepped thread. */
6217 if (switch_back_to_stepped_thread (ecs
))
6220 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
6223 fprintf_unfiltered (gdb_stdlog
,
6224 "infrun: step-resume breakpoint is inserted\n");
6226 /* Having a step-resume breakpoint overrides anything
6227 else having to do with stepping commands until
6228 that breakpoint is reached. */
6233 if (ecs
->event_thread
->control
.step_range_end
== 0)
6236 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
6237 /* Likewise if we aren't even stepping. */
6242 /* Re-fetch current thread's frame in case the code above caused
6243 the frame cache to be re-initialized, making our FRAME variable
6244 a dangling pointer. */
6245 frame
= get_current_frame ();
6246 gdbarch
= get_frame_arch (frame
);
6247 fill_in_stop_func (gdbarch
, ecs
);
6249 /* If stepping through a line, keep going if still within it.
6251 Note that step_range_end is the address of the first instruction
6252 beyond the step range, and NOT the address of the last instruction
6255 Note also that during reverse execution, we may be stepping
6256 through a function epilogue and therefore must detect when
6257 the current-frame changes in the middle of a line. */
6259 if (pc_in_thread_step_range (ecs
->event_thread
->suspend
.stop_pc
,
6261 && (execution_direction
!= EXEC_REVERSE
6262 || frame_id_eq (get_frame_id (frame
),
6263 ecs
->event_thread
->control
.step_frame_id
)))
6267 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
6268 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
6269 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
6271 /* Tentatively re-enable range stepping; `resume' disables it if
6272 necessary (e.g., if we're stepping over a breakpoint or we
6273 have software watchpoints). */
6274 ecs
->event_thread
->control
.may_range_step
= 1;
6276 /* When stepping backward, stop at beginning of line range
6277 (unless it's the function entry point, in which case
6278 keep going back to the call point). */
6279 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6280 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
6281 && stop_pc
!= ecs
->stop_func_start
6282 && execution_direction
== EXEC_REVERSE
)
6283 end_stepping_range (ecs
);
6290 /* We stepped out of the stepping range. */
6292 /* If we are stepping at the source level and entered the runtime
6293 loader dynamic symbol resolution code...
6295 EXEC_FORWARD: we keep on single stepping until we exit the run
6296 time loader code and reach the callee's address.
6298 EXEC_REVERSE: we've already executed the callee (backward), and
6299 the runtime loader code is handled just like any other
6300 undebuggable function call. Now we need only keep stepping
6301 backward through the trampoline code, and that's handled further
6302 down, so there is nothing for us to do here. */
6304 if (execution_direction
!= EXEC_REVERSE
6305 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6306 && in_solib_dynsym_resolve_code (ecs
->event_thread
->suspend
.stop_pc
))
6308 CORE_ADDR pc_after_resolver
=
6309 gdbarch_skip_solib_resolver (gdbarch
,
6310 ecs
->event_thread
->suspend
.stop_pc
);
6313 fprintf_unfiltered (gdb_stdlog
,
6314 "infrun: stepped into dynsym resolve code\n");
6316 if (pc_after_resolver
)
6318 /* Set up a step-resume breakpoint at the address
6319 indicated by SKIP_SOLIB_RESOLVER. */
6320 symtab_and_line sr_sal
;
6321 sr_sal
.pc
= pc_after_resolver
;
6322 sr_sal
.pspace
= get_frame_program_space (frame
);
6324 insert_step_resume_breakpoint_at_sal (gdbarch
,
6325 sr_sal
, null_frame_id
);
6332 /* Step through an indirect branch thunk. */
6333 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6334 && gdbarch_in_indirect_branch_thunk (gdbarch
,
6335 ecs
->event_thread
->suspend
.stop_pc
))
6338 fprintf_unfiltered (gdb_stdlog
,
6339 "infrun: stepped into indirect branch thunk\n");
6344 if (ecs
->event_thread
->control
.step_range_end
!= 1
6345 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6346 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6347 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
6350 fprintf_unfiltered (gdb_stdlog
,
6351 "infrun: stepped into signal trampoline\n");
6352 /* The inferior, while doing a "step" or "next", has ended up in
6353 a signal trampoline (either by a signal being delivered or by
6354 the signal handler returning). Just single-step until the
6355 inferior leaves the trampoline (either by calling the handler
6361 /* If we're in the return path from a shared library trampoline,
6362 we want to proceed through the trampoline when stepping. */
6363 /* macro/2012-04-25: This needs to come before the subroutine
6364 call check below as on some targets return trampolines look
6365 like subroutine calls (MIPS16 return thunks). */
6366 if (gdbarch_in_solib_return_trampoline (gdbarch
,
6367 ecs
->event_thread
->suspend
.stop_pc
,
6368 ecs
->stop_func_name
)
6369 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6371 /* Determine where this trampoline returns. */
6372 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6373 CORE_ADDR real_stop_pc
6374 = gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6377 fprintf_unfiltered (gdb_stdlog
,
6378 "infrun: stepped into solib return tramp\n");
6380 /* Only proceed through if we know where it's going. */
6383 /* And put the step-breakpoint there and go until there. */
6384 symtab_and_line sr_sal
;
6385 sr_sal
.pc
= real_stop_pc
;
6386 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6387 sr_sal
.pspace
= get_frame_program_space (frame
);
6389 /* Do not specify what the fp should be when we stop since
6390 on some machines the prologue is where the new fp value
6392 insert_step_resume_breakpoint_at_sal (gdbarch
,
6393 sr_sal
, null_frame_id
);
6395 /* Restart without fiddling with the step ranges or
6402 /* Check for subroutine calls. The check for the current frame
6403 equalling the step ID is not necessary - the check of the
6404 previous frame's ID is sufficient - but it is a common case and
6405 cheaper than checking the previous frame's ID.
6407 NOTE: frame_id_eq will never report two invalid frame IDs as
6408 being equal, so to get into this block, both the current and
6409 previous frame must have valid frame IDs. */
6410 /* The outer_frame_id check is a heuristic to detect stepping
6411 through startup code. If we step over an instruction which
6412 sets the stack pointer from an invalid value to a valid value,
6413 we may detect that as a subroutine call from the mythical
6414 "outermost" function. This could be fixed by marking
6415 outermost frames as !stack_p,code_p,special_p. Then the
6416 initial outermost frame, before sp was valid, would
6417 have code_addr == &_start. See the comment in frame_id_eq
6419 if (!frame_id_eq (get_stack_frame_id (frame
),
6420 ecs
->event_thread
->control
.step_stack_frame_id
)
6421 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6422 ecs
->event_thread
->control
.step_stack_frame_id
)
6423 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
6425 || (ecs
->event_thread
->control
.step_start_function
6426 != find_pc_function (ecs
->event_thread
->suspend
.stop_pc
)))))
6428 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6429 CORE_ADDR real_stop_pc
;
6432 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
6434 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
6436 /* I presume that step_over_calls is only 0 when we're
6437 supposed to be stepping at the assembly language level
6438 ("stepi"). Just stop. */
6439 /* And this works the same backward as frontward. MVS */
6440 end_stepping_range (ecs
);
6444 /* Reverse stepping through solib trampolines. */
6446 if (execution_direction
== EXEC_REVERSE
6447 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6448 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6449 || (ecs
->stop_func_start
== 0
6450 && in_solib_dynsym_resolve_code (stop_pc
))))
6452 /* Any solib trampoline code can be handled in reverse
6453 by simply continuing to single-step. We have already
6454 executed the solib function (backwards), and a few
6455 steps will take us back through the trampoline to the
6461 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6463 /* We're doing a "next".
6465 Normal (forward) execution: set a breakpoint at the
6466 callee's return address (the address at which the caller
6469 Reverse (backward) execution. set the step-resume
6470 breakpoint at the start of the function that we just
6471 stepped into (backwards), and continue to there. When we
6472 get there, we'll need to single-step back to the caller. */
6474 if (execution_direction
== EXEC_REVERSE
)
6476 /* If we're already at the start of the function, we've either
6477 just stepped backward into a single instruction function,
6478 or stepped back out of a signal handler to the first instruction
6479 of the function. Just keep going, which will single-step back
6481 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
6483 /* Normal function call return (static or dynamic). */
6484 symtab_and_line sr_sal
;
6485 sr_sal
.pc
= ecs
->stop_func_start
;
6486 sr_sal
.pspace
= get_frame_program_space (frame
);
6487 insert_step_resume_breakpoint_at_sal (gdbarch
,
6488 sr_sal
, null_frame_id
);
6492 insert_step_resume_breakpoint_at_caller (frame
);
6498 /* If we are in a function call trampoline (a stub between the
6499 calling routine and the real function), locate the real
6500 function. That's what tells us (a) whether we want to step
6501 into it at all, and (b) what prologue we want to run to the
6502 end of, if we do step into it. */
6503 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
6504 if (real_stop_pc
== 0)
6505 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6506 if (real_stop_pc
!= 0)
6507 ecs
->stop_func_start
= real_stop_pc
;
6509 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
6511 symtab_and_line sr_sal
;
6512 sr_sal
.pc
= ecs
->stop_func_start
;
6513 sr_sal
.pspace
= get_frame_program_space (frame
);
6515 insert_step_resume_breakpoint_at_sal (gdbarch
,
6516 sr_sal
, null_frame_id
);
6521 /* If we have line number information for the function we are
6522 thinking of stepping into and the function isn't on the skip
6525 If there are several symtabs at that PC (e.g. with include
6526 files), just want to know whether *any* of them have line
6527 numbers. find_pc_line handles this. */
6529 struct symtab_and_line tmp_sal
;
6531 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
6532 if (tmp_sal
.line
!= 0
6533 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
6536 if (execution_direction
== EXEC_REVERSE
)
6537 handle_step_into_function_backward (gdbarch
, ecs
);
6539 handle_step_into_function (gdbarch
, ecs
);
6544 /* If we have no line number and the step-stop-if-no-debug is
6545 set, we stop the step so that the user has a chance to switch
6546 in assembly mode. */
6547 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6548 && step_stop_if_no_debug
)
6550 end_stepping_range (ecs
);
6554 if (execution_direction
== EXEC_REVERSE
)
6556 /* If we're already at the start of the function, we've either just
6557 stepped backward into a single instruction function without line
6558 number info, or stepped back out of a signal handler to the first
6559 instruction of the function without line number info. Just keep
6560 going, which will single-step back to the caller. */
6561 if (ecs
->stop_func_start
!= stop_pc
)
6563 /* Set a breakpoint at callee's start address.
6564 From there we can step once and be back in the caller. */
6565 symtab_and_line sr_sal
;
6566 sr_sal
.pc
= ecs
->stop_func_start
;
6567 sr_sal
.pspace
= get_frame_program_space (frame
);
6568 insert_step_resume_breakpoint_at_sal (gdbarch
,
6569 sr_sal
, null_frame_id
);
6573 /* Set a breakpoint at callee's return address (the address
6574 at which the caller will resume). */
6575 insert_step_resume_breakpoint_at_caller (frame
);
6581 /* Reverse stepping through solib trampolines. */
6583 if (execution_direction
== EXEC_REVERSE
6584 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6586 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6588 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6589 || (ecs
->stop_func_start
== 0
6590 && in_solib_dynsym_resolve_code (stop_pc
)))
6592 /* Any solib trampoline code can be handled in reverse
6593 by simply continuing to single-step. We have already
6594 executed the solib function (backwards), and a few
6595 steps will take us back through the trampoline to the
6600 else if (in_solib_dynsym_resolve_code (stop_pc
))
6602 /* Stepped backward into the solib dynsym resolver.
6603 Set a breakpoint at its start and continue, then
6604 one more step will take us out. */
6605 symtab_and_line sr_sal
;
6606 sr_sal
.pc
= ecs
->stop_func_start
;
6607 sr_sal
.pspace
= get_frame_program_space (frame
);
6608 insert_step_resume_breakpoint_at_sal (gdbarch
,
6609 sr_sal
, null_frame_id
);
6615 stop_pc_sal
= find_pc_line (ecs
->event_thread
->suspend
.stop_pc
, 0);
6617 /* NOTE: tausq/2004-05-24: This if block used to be done before all
6618 the trampoline processing logic, however, there are some trampolines
6619 that have no names, so we should do trampoline handling first. */
6620 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6621 && ecs
->stop_func_name
== NULL
6622 && stop_pc_sal
.line
== 0)
6625 fprintf_unfiltered (gdb_stdlog
,
6626 "infrun: stepped into undebuggable function\n");
6628 /* The inferior just stepped into, or returned to, an
6629 undebuggable function (where there is no debugging information
6630 and no line number corresponding to the address where the
6631 inferior stopped). Since we want to skip this kind of code,
6632 we keep going until the inferior returns from this
6633 function - unless the user has asked us not to (via
6634 set step-mode) or we no longer know how to get back
6635 to the call site. */
6636 if (step_stop_if_no_debug
6637 || !frame_id_p (frame_unwind_caller_id (frame
)))
6639 /* If we have no line number and the step-stop-if-no-debug
6640 is set, we stop the step so that the user has a chance to
6641 switch in assembly mode. */
6642 end_stepping_range (ecs
);
6647 /* Set a breakpoint at callee's return address (the address
6648 at which the caller will resume). */
6649 insert_step_resume_breakpoint_at_caller (frame
);
6655 if (ecs
->event_thread
->control
.step_range_end
== 1)
6657 /* It is stepi or nexti. We always want to stop stepping after
6660 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
6661 end_stepping_range (ecs
);
6665 if (stop_pc_sal
.line
== 0)
6667 /* We have no line number information. That means to stop
6668 stepping (does this always happen right after one instruction,
6669 when we do "s" in a function with no line numbers,
6670 or can this happen as a result of a return or longjmp?). */
6672 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
6673 end_stepping_range (ecs
);
6677 /* Look for "calls" to inlined functions, part one. If the inline
6678 frame machinery detected some skipped call sites, we have entered
6679 a new inline function. */
6681 if (frame_id_eq (get_frame_id (get_current_frame ()),
6682 ecs
->event_thread
->control
.step_frame_id
)
6683 && inline_skipped_frames (ecs
->event_thread
))
6686 fprintf_unfiltered (gdb_stdlog
,
6687 "infrun: stepped into inlined function\n");
6689 symtab_and_line call_sal
= find_frame_sal (get_current_frame ());
6691 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
6693 /* For "step", we're going to stop. But if the call site
6694 for this inlined function is on the same source line as
6695 we were previously stepping, go down into the function
6696 first. Otherwise stop at the call site. */
6698 if (call_sal
.line
== ecs
->event_thread
->current_line
6699 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6700 step_into_inline_frame (ecs
->event_thread
);
6702 end_stepping_range (ecs
);
6707 /* For "next", we should stop at the call site if it is on a
6708 different source line. Otherwise continue through the
6709 inlined function. */
6710 if (call_sal
.line
== ecs
->event_thread
->current_line
6711 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6714 end_stepping_range (ecs
);
6719 /* Look for "calls" to inlined functions, part two. If we are still
6720 in the same real function we were stepping through, but we have
6721 to go further up to find the exact frame ID, we are stepping
6722 through a more inlined call beyond its call site. */
6724 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
6725 && !frame_id_eq (get_frame_id (get_current_frame ()),
6726 ecs
->event_thread
->control
.step_frame_id
)
6727 && stepped_in_from (get_current_frame (),
6728 ecs
->event_thread
->control
.step_frame_id
))
6731 fprintf_unfiltered (gdb_stdlog
,
6732 "infrun: stepping through inlined function\n");
6734 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6737 end_stepping_range (ecs
);
6741 if ((ecs
->event_thread
->suspend
.stop_pc
== stop_pc_sal
.pc
)
6742 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
6743 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
6745 /* We are at the start of a different line. So stop. Note that
6746 we don't stop if we step into the middle of a different line.
6747 That is said to make things like for (;;) statements work
6750 fprintf_unfiltered (gdb_stdlog
,
6751 "infrun: stepped to a different line\n");
6752 end_stepping_range (ecs
);
6756 /* We aren't done stepping.
6758 Optimize by setting the stepping range to the line.
6759 (We might not be in the original line, but if we entered a
6760 new line in mid-statement, we continue stepping. This makes
6761 things like for(;;) statements work better.) */
6763 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
6764 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
6765 ecs
->event_thread
->control
.may_range_step
= 1;
6766 set_step_info (frame
, stop_pc_sal
);
6769 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
6773 /* In all-stop mode, if we're currently stepping but have stopped in
6774 some other thread, we may need to switch back to the stepped
6775 thread. Returns true we set the inferior running, false if we left
6776 it stopped (and the event needs further processing). */
6779 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
6781 if (!target_is_non_stop_p ())
6783 struct thread_info
*stepping_thread
;
6785 /* If any thread is blocked on some internal breakpoint, and we
6786 simply need to step over that breakpoint to get it going
6787 again, do that first. */
6789 /* However, if we see an event for the stepping thread, then we
6790 know all other threads have been moved past their breakpoints
6791 already. Let the caller check whether the step is finished,
6792 etc., before deciding to move it past a breakpoint. */
6793 if (ecs
->event_thread
->control
.step_range_end
!= 0)
6796 /* Check if the current thread is blocked on an incomplete
6797 step-over, interrupted by a random signal. */
6798 if (ecs
->event_thread
->control
.trap_expected
6799 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
6803 fprintf_unfiltered (gdb_stdlog
,
6804 "infrun: need to finish step-over of [%s]\n",
6805 target_pid_to_str (ecs
->event_thread
->ptid
).c_str ());
6811 /* Check if the current thread is blocked by a single-step
6812 breakpoint of another thread. */
6813 if (ecs
->hit_singlestep_breakpoint
)
6817 fprintf_unfiltered (gdb_stdlog
,
6818 "infrun: need to step [%s] over single-step "
6820 target_pid_to_str (ecs
->ptid
).c_str ());
6826 /* If this thread needs yet another step-over (e.g., stepping
6827 through a delay slot), do it first before moving on to
6829 if (thread_still_needs_step_over (ecs
->event_thread
))
6833 fprintf_unfiltered (gdb_stdlog
,
6834 "infrun: thread [%s] still needs step-over\n",
6835 target_pid_to_str (ecs
->event_thread
->ptid
).c_str ());
6841 /* If scheduler locking applies even if not stepping, there's no
6842 need to walk over threads. Above we've checked whether the
6843 current thread is stepping. If some other thread not the
6844 event thread is stepping, then it must be that scheduler
6845 locking is not in effect. */
6846 if (schedlock_applies (ecs
->event_thread
))
6849 /* Otherwise, we no longer expect a trap in the current thread.
6850 Clear the trap_expected flag before switching back -- this is
6851 what keep_going does as well, if we call it. */
6852 ecs
->event_thread
->control
.trap_expected
= 0;
6854 /* Likewise, clear the signal if it should not be passed. */
6855 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
6856 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6858 /* Do all pending step-overs before actually proceeding with
6860 if (start_step_over ())
6862 prepare_to_wait (ecs
);
6866 /* Look for the stepping/nexting thread. */
6867 stepping_thread
= NULL
;
6869 for (thread_info
*tp
: all_non_exited_threads ())
6871 /* Ignore threads of processes the caller is not
6874 && tp
->ptid
.pid () != ecs
->ptid
.pid ())
6877 /* When stepping over a breakpoint, we lock all threads
6878 except the one that needs to move past the breakpoint.
6879 If a non-event thread has this set, the "incomplete
6880 step-over" check above should have caught it earlier. */
6881 if (tp
->control
.trap_expected
)
6883 internal_error (__FILE__
, __LINE__
,
6884 "[%s] has inconsistent state: "
6885 "trap_expected=%d\n",
6886 target_pid_to_str (tp
->ptid
).c_str (),
6887 tp
->control
.trap_expected
);
6890 /* Did we find the stepping thread? */
6891 if (tp
->control
.step_range_end
)
6893 /* Yep. There should only one though. */
6894 gdb_assert (stepping_thread
== NULL
);
6896 /* The event thread is handled at the top, before we
6898 gdb_assert (tp
!= ecs
->event_thread
);
6900 /* If some thread other than the event thread is
6901 stepping, then scheduler locking can't be in effect,
6902 otherwise we wouldn't have resumed the current event
6903 thread in the first place. */
6904 gdb_assert (!schedlock_applies (tp
));
6906 stepping_thread
= tp
;
6910 if (stepping_thread
!= NULL
)
6913 fprintf_unfiltered (gdb_stdlog
,
6914 "infrun: switching back to stepped thread\n");
6916 if (keep_going_stepped_thread (stepping_thread
))
6918 prepare_to_wait (ecs
);
6927 /* Set a previously stepped thread back to stepping. Returns true on
6928 success, false if the resume is not possible (e.g., the thread
6932 keep_going_stepped_thread (struct thread_info
*tp
)
6934 struct frame_info
*frame
;
6935 struct execution_control_state ecss
;
6936 struct execution_control_state
*ecs
= &ecss
;
6938 /* If the stepping thread exited, then don't try to switch back and
6939 resume it, which could fail in several different ways depending
6940 on the target. Instead, just keep going.
6942 We can find a stepping dead thread in the thread list in two
6945 - The target supports thread exit events, and when the target
6946 tries to delete the thread from the thread list, inferior_ptid
6947 pointed at the exiting thread. In such case, calling
6948 delete_thread does not really remove the thread from the list;
6949 instead, the thread is left listed, with 'exited' state.
6951 - The target's debug interface does not support thread exit
6952 events, and so we have no idea whatsoever if the previously
6953 stepping thread is still alive. For that reason, we need to
6954 synchronously query the target now. */
6956 if (tp
->state
== THREAD_EXITED
|| !target_thread_alive (tp
->ptid
))
6959 fprintf_unfiltered (gdb_stdlog
,
6960 "infrun: not resuming previously "
6961 "stepped thread, it has vanished\n");
6968 fprintf_unfiltered (gdb_stdlog
,
6969 "infrun: resuming previously stepped thread\n");
6971 reset_ecs (ecs
, tp
);
6972 switch_to_thread (tp
);
6974 tp
->suspend
.stop_pc
= regcache_read_pc (get_thread_regcache (tp
));
6975 frame
= get_current_frame ();
6977 /* If the PC of the thread we were trying to single-step has
6978 changed, then that thread has trapped or been signaled, but the
6979 event has not been reported to GDB yet. Re-poll the target
6980 looking for this particular thread's event (i.e. temporarily
6981 enable schedlock) by:
6983 - setting a break at the current PC
6984 - resuming that particular thread, only (by setting trap
6987 This prevents us continuously moving the single-step breakpoint
6988 forward, one instruction at a time, overstepping. */
6990 if (tp
->suspend
.stop_pc
!= tp
->prev_pc
)
6995 fprintf_unfiltered (gdb_stdlog
,
6996 "infrun: expected thread advanced also (%s -> %s)\n",
6997 paddress (target_gdbarch (), tp
->prev_pc
),
6998 paddress (target_gdbarch (), tp
->suspend
.stop_pc
));
7000 /* Clear the info of the previous step-over, as it's no longer
7001 valid (if the thread was trying to step over a breakpoint, it
7002 has already succeeded). It's what keep_going would do too,
7003 if we called it. Do this before trying to insert the sss
7004 breakpoint, otherwise if we were previously trying to step
7005 over this exact address in another thread, the breakpoint is
7007 clear_step_over_info ();
7008 tp
->control
.trap_expected
= 0;
7010 insert_single_step_breakpoint (get_frame_arch (frame
),
7011 get_frame_address_space (frame
),
7012 tp
->suspend
.stop_pc
);
7015 resume_ptid
= internal_resume_ptid (tp
->control
.stepping_command
);
7016 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
7021 fprintf_unfiltered (gdb_stdlog
,
7022 "infrun: expected thread still hasn't advanced\n");
7024 keep_going_pass_signal (ecs
);
7029 /* Is thread TP in the middle of (software or hardware)
7030 single-stepping? (Note the result of this function must never be
7031 passed directly as target_resume's STEP parameter.) */
7034 currently_stepping (struct thread_info
*tp
)
7036 return ((tp
->control
.step_range_end
7037 && tp
->control
.step_resume_breakpoint
== NULL
)
7038 || tp
->control
.trap_expected
7039 || tp
->stepped_breakpoint
7040 || bpstat_should_step ());
7043 /* Inferior has stepped into a subroutine call with source code that
7044 we should not step over. Do step to the first line of code in
7048 handle_step_into_function (struct gdbarch
*gdbarch
,
7049 struct execution_control_state
*ecs
)
7051 fill_in_stop_func (gdbarch
, ecs
);
7053 compunit_symtab
*cust
7054 = find_pc_compunit_symtab (ecs
->event_thread
->suspend
.stop_pc
);
7055 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7056 ecs
->stop_func_start
7057 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7059 symtab_and_line stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7060 /* Use the step_resume_break to step until the end of the prologue,
7061 even if that involves jumps (as it seems to on the vax under
7063 /* If the prologue ends in the middle of a source line, continue to
7064 the end of that source line (if it is still within the function).
7065 Otherwise, just go to end of prologue. */
7066 if (stop_func_sal
.end
7067 && stop_func_sal
.pc
!= ecs
->stop_func_start
7068 && stop_func_sal
.end
< ecs
->stop_func_end
)
7069 ecs
->stop_func_start
= stop_func_sal
.end
;
7071 /* Architectures which require breakpoint adjustment might not be able
7072 to place a breakpoint at the computed address. If so, the test
7073 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7074 ecs->stop_func_start to an address at which a breakpoint may be
7075 legitimately placed.
7077 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7078 made, GDB will enter an infinite loop when stepping through
7079 optimized code consisting of VLIW instructions which contain
7080 subinstructions corresponding to different source lines. On
7081 FR-V, it's not permitted to place a breakpoint on any but the
7082 first subinstruction of a VLIW instruction. When a breakpoint is
7083 set, GDB will adjust the breakpoint address to the beginning of
7084 the VLIW instruction. Thus, we need to make the corresponding
7085 adjustment here when computing the stop address. */
7087 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
7089 ecs
->stop_func_start
7090 = gdbarch_adjust_breakpoint_address (gdbarch
,
7091 ecs
->stop_func_start
);
7094 if (ecs
->stop_func_start
== ecs
->event_thread
->suspend
.stop_pc
)
7096 /* We are already there: stop now. */
7097 end_stepping_range (ecs
);
7102 /* Put the step-breakpoint there and go until there. */
7103 symtab_and_line sr_sal
;
7104 sr_sal
.pc
= ecs
->stop_func_start
;
7105 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
7106 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
7108 /* Do not specify what the fp should be when we stop since on
7109 some machines the prologue is where the new fp value is
7111 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
7113 /* And make sure stepping stops right away then. */
7114 ecs
->event_thread
->control
.step_range_end
7115 = ecs
->event_thread
->control
.step_range_start
;
7120 /* Inferior has stepped backward into a subroutine call with source
7121 code that we should not step over. Do step to the beginning of the
7122 last line of code in it. */
7125 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
7126 struct execution_control_state
*ecs
)
7128 struct compunit_symtab
*cust
;
7129 struct symtab_and_line stop_func_sal
;
7131 fill_in_stop_func (gdbarch
, ecs
);
7133 cust
= find_pc_compunit_symtab (ecs
->event_thread
->suspend
.stop_pc
);
7134 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7135 ecs
->stop_func_start
7136 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7138 stop_func_sal
= find_pc_line (ecs
->event_thread
->suspend
.stop_pc
, 0);
7140 /* OK, we're just going to keep stepping here. */
7141 if (stop_func_sal
.pc
== ecs
->event_thread
->suspend
.stop_pc
)
7143 /* We're there already. Just stop stepping now. */
7144 end_stepping_range (ecs
);
7148 /* Else just reset the step range and keep going.
7149 No step-resume breakpoint, they don't work for
7150 epilogues, which can have multiple entry paths. */
7151 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
7152 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
7158 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7159 This is used to both functions and to skip over code. */
7162 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
7163 struct symtab_and_line sr_sal
,
7164 struct frame_id sr_id
,
7165 enum bptype sr_type
)
7167 /* There should never be more than one step-resume or longjmp-resume
7168 breakpoint per thread, so we should never be setting a new
7169 step_resume_breakpoint when one is already active. */
7170 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
7171 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
7174 fprintf_unfiltered (gdb_stdlog
,
7175 "infrun: inserting step-resume breakpoint at %s\n",
7176 paddress (gdbarch
, sr_sal
.pc
));
7178 inferior_thread ()->control
.step_resume_breakpoint
7179 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
).release ();
7183 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
7184 struct symtab_and_line sr_sal
,
7185 struct frame_id sr_id
)
7187 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
7192 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7193 This is used to skip a potential signal handler.
7195 This is called with the interrupted function's frame. The signal
7196 handler, when it returns, will resume the interrupted function at
7200 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
7202 gdb_assert (return_frame
!= NULL
);
7204 struct gdbarch
*gdbarch
= get_frame_arch (return_frame
);
7206 symtab_and_line sr_sal
;
7207 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
7208 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7209 sr_sal
.pspace
= get_frame_program_space (return_frame
);
7211 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
7212 get_stack_frame_id (return_frame
),
7216 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7217 is used to skip a function after stepping into it (for "next" or if
7218 the called function has no debugging information).
7220 The current function has almost always been reached by single
7221 stepping a call or return instruction. NEXT_FRAME belongs to the
7222 current function, and the breakpoint will be set at the caller's
7225 This is a separate function rather than reusing
7226 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7227 get_prev_frame, which may stop prematurely (see the implementation
7228 of frame_unwind_caller_id for an example). */
7231 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
7233 /* We shouldn't have gotten here if we don't know where the call site
7235 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
7237 struct gdbarch
*gdbarch
= frame_unwind_caller_arch (next_frame
);
7239 symtab_and_line sr_sal
;
7240 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
7241 frame_unwind_caller_pc (next_frame
));
7242 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7243 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
7245 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
7246 frame_unwind_caller_id (next_frame
));
7249 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7250 new breakpoint at the target of a jmp_buf. The handling of
7251 longjmp-resume uses the same mechanisms used for handling
7252 "step-resume" breakpoints. */
7255 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
7257 /* There should never be more than one longjmp-resume breakpoint per
7258 thread, so we should never be setting a new
7259 longjmp_resume_breakpoint when one is already active. */
7260 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
7263 fprintf_unfiltered (gdb_stdlog
,
7264 "infrun: inserting longjmp-resume breakpoint at %s\n",
7265 paddress (gdbarch
, pc
));
7267 inferior_thread ()->control
.exception_resume_breakpoint
=
7268 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
).release ();
7271 /* Insert an exception resume breakpoint. TP is the thread throwing
7272 the exception. The block B is the block of the unwinder debug hook
7273 function. FRAME is the frame corresponding to the call to this
7274 function. SYM is the symbol of the function argument holding the
7275 target PC of the exception. */
7278 insert_exception_resume_breakpoint (struct thread_info
*tp
,
7279 const struct block
*b
,
7280 struct frame_info
*frame
,
7285 struct block_symbol vsym
;
7286 struct value
*value
;
7288 struct breakpoint
*bp
;
7290 vsym
= lookup_symbol_search_name (SYMBOL_SEARCH_NAME (sym
),
7292 value
= read_var_value (vsym
.symbol
, vsym
.block
, frame
);
7293 /* If the value was optimized out, revert to the old behavior. */
7294 if (! value_optimized_out (value
))
7296 handler
= value_as_address (value
);
7299 fprintf_unfiltered (gdb_stdlog
,
7300 "infrun: exception resume at %lx\n",
7301 (unsigned long) handler
);
7303 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7305 bp_exception_resume
).release ();
7307 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7310 bp
->thread
= tp
->global_num
;
7311 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7314 catch (const gdb_exception_error
&e
)
7316 /* We want to ignore errors here. */
7320 /* A helper for check_exception_resume that sets an
7321 exception-breakpoint based on a SystemTap probe. */
7324 insert_exception_resume_from_probe (struct thread_info
*tp
,
7325 const struct bound_probe
*probe
,
7326 struct frame_info
*frame
)
7328 struct value
*arg_value
;
7330 struct breakpoint
*bp
;
7332 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
7336 handler
= value_as_address (arg_value
);
7339 fprintf_unfiltered (gdb_stdlog
,
7340 "infrun: exception resume at %s\n",
7341 paddress (get_objfile_arch (probe
->objfile
),
7344 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7345 handler
, bp_exception_resume
).release ();
7346 bp
->thread
= tp
->global_num
;
7347 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7350 /* This is called when an exception has been intercepted. Check to
7351 see whether the exception's destination is of interest, and if so,
7352 set an exception resume breakpoint there. */
7355 check_exception_resume (struct execution_control_state
*ecs
,
7356 struct frame_info
*frame
)
7358 struct bound_probe probe
;
7359 struct symbol
*func
;
7361 /* First see if this exception unwinding breakpoint was set via a
7362 SystemTap probe point. If so, the probe has two arguments: the
7363 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7364 set a breakpoint there. */
7365 probe
= find_probe_by_pc (get_frame_pc (frame
));
7368 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
7372 func
= get_frame_function (frame
);
7378 const struct block
*b
;
7379 struct block_iterator iter
;
7383 /* The exception breakpoint is a thread-specific breakpoint on
7384 the unwinder's debug hook, declared as:
7386 void _Unwind_DebugHook (void *cfa, void *handler);
7388 The CFA argument indicates the frame to which control is
7389 about to be transferred. HANDLER is the destination PC.
7391 We ignore the CFA and set a temporary breakpoint at HANDLER.
7392 This is not extremely efficient but it avoids issues in gdb
7393 with computing the DWARF CFA, and it also works even in weird
7394 cases such as throwing an exception from inside a signal
7397 b
= SYMBOL_BLOCK_VALUE (func
);
7398 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
7400 if (!SYMBOL_IS_ARGUMENT (sym
))
7407 insert_exception_resume_breakpoint (ecs
->event_thread
,
7413 catch (const gdb_exception_error
&e
)
7419 stop_waiting (struct execution_control_state
*ecs
)
7422 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
7424 /* Let callers know we don't want to wait for the inferior anymore. */
7425 ecs
->wait_some_more
= 0;
7427 /* If all-stop, but the target is always in non-stop mode, stop all
7428 threads now that we're presenting the stop to the user. */
7429 if (!non_stop
&& target_is_non_stop_p ())
7430 stop_all_threads ();
7433 /* Like keep_going, but passes the signal to the inferior, even if the
7434 signal is set to nopass. */
7437 keep_going_pass_signal (struct execution_control_state
*ecs
)
7439 gdb_assert (ecs
->event_thread
->ptid
== inferior_ptid
);
7440 gdb_assert (!ecs
->event_thread
->resumed
);
7442 /* Save the pc before execution, to compare with pc after stop. */
7443 ecs
->event_thread
->prev_pc
7444 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
7446 if (ecs
->event_thread
->control
.trap_expected
)
7448 struct thread_info
*tp
= ecs
->event_thread
;
7451 fprintf_unfiltered (gdb_stdlog
,
7452 "infrun: %s has trap_expected set, "
7453 "resuming to collect trap\n",
7454 target_pid_to_str (tp
->ptid
).c_str ());
7456 /* We haven't yet gotten our trap, and either: intercepted a
7457 non-signal event (e.g., a fork); or took a signal which we
7458 are supposed to pass through to the inferior. Simply
7460 resume (ecs
->event_thread
->suspend
.stop_signal
);
7462 else if (step_over_info_valid_p ())
7464 /* Another thread is stepping over a breakpoint in-line. If
7465 this thread needs a step-over too, queue the request. In
7466 either case, this resume must be deferred for later. */
7467 struct thread_info
*tp
= ecs
->event_thread
;
7469 if (ecs
->hit_singlestep_breakpoint
7470 || thread_still_needs_step_over (tp
))
7473 fprintf_unfiltered (gdb_stdlog
,
7474 "infrun: step-over already in progress: "
7475 "step-over for %s deferred\n",
7476 target_pid_to_str (tp
->ptid
).c_str ());
7477 thread_step_over_chain_enqueue (tp
);
7482 fprintf_unfiltered (gdb_stdlog
,
7483 "infrun: step-over in progress: "
7484 "resume of %s deferred\n",
7485 target_pid_to_str (tp
->ptid
).c_str ());
7490 struct regcache
*regcache
= get_current_regcache ();
7493 step_over_what step_what
;
7495 /* Either the trap was not expected, but we are continuing
7496 anyway (if we got a signal, the user asked it be passed to
7499 We got our expected trap, but decided we should resume from
7502 We're going to run this baby now!
7504 Note that insert_breakpoints won't try to re-insert
7505 already inserted breakpoints. Therefore, we don't
7506 care if breakpoints were already inserted, or not. */
7508 /* If we need to step over a breakpoint, and we're not using
7509 displaced stepping to do so, insert all breakpoints
7510 (watchpoints, etc.) but the one we're stepping over, step one
7511 instruction, and then re-insert the breakpoint when that step
7514 step_what
= thread_still_needs_step_over (ecs
->event_thread
);
7516 remove_bp
= (ecs
->hit_singlestep_breakpoint
7517 || (step_what
& STEP_OVER_BREAKPOINT
));
7518 remove_wps
= (step_what
& STEP_OVER_WATCHPOINT
);
7520 /* We can't use displaced stepping if we need to step past a
7521 watchpoint. The instruction copied to the scratch pad would
7522 still trigger the watchpoint. */
7524 && (remove_wps
|| !use_displaced_stepping (ecs
->event_thread
)))
7526 set_step_over_info (regcache
->aspace (),
7527 regcache_read_pc (regcache
), remove_wps
,
7528 ecs
->event_thread
->global_num
);
7530 else if (remove_wps
)
7531 set_step_over_info (NULL
, 0, remove_wps
, -1);
7533 /* If we now need to do an in-line step-over, we need to stop
7534 all other threads. Note this must be done before
7535 insert_breakpoints below, because that removes the breakpoint
7536 we're about to step over, otherwise other threads could miss
7538 if (step_over_info_valid_p () && target_is_non_stop_p ())
7539 stop_all_threads ();
7541 /* Stop stepping if inserting breakpoints fails. */
7544 insert_breakpoints ();
7546 catch (const gdb_exception_error
&e
)
7548 exception_print (gdb_stderr
, e
);
7550 clear_step_over_info ();
7554 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
7556 resume (ecs
->event_thread
->suspend
.stop_signal
);
7559 prepare_to_wait (ecs
);
7562 /* Called when we should continue running the inferior, because the
7563 current event doesn't cause a user visible stop. This does the
7564 resuming part; waiting for the next event is done elsewhere. */
7567 keep_going (struct execution_control_state
*ecs
)
7569 if (ecs
->event_thread
->control
.trap_expected
7570 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
7571 ecs
->event_thread
->control
.trap_expected
= 0;
7573 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7574 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7575 keep_going_pass_signal (ecs
);
7578 /* This function normally comes after a resume, before
7579 handle_inferior_event exits. It takes care of any last bits of
7580 housekeeping, and sets the all-important wait_some_more flag. */
7583 prepare_to_wait (struct execution_control_state
*ecs
)
7586 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
7588 ecs
->wait_some_more
= 1;
7590 if (!target_is_async_p ())
7591 mark_infrun_async_event_handler ();
7594 /* We are done with the step range of a step/next/si/ni command.
7595 Called once for each n of a "step n" operation. */
7598 end_stepping_range (struct execution_control_state
*ecs
)
7600 ecs
->event_thread
->control
.stop_step
= 1;
7604 /* Several print_*_reason functions to print why the inferior has stopped.
7605 We always print something when the inferior exits, or receives a signal.
7606 The rest of the cases are dealt with later on in normal_stop and
7607 print_it_typical. Ideally there should be a call to one of these
7608 print_*_reason functions functions from handle_inferior_event each time
7609 stop_waiting is called.
7611 Note that we don't call these directly, instead we delegate that to
7612 the interpreters, through observers. Interpreters then call these
7613 with whatever uiout is right. */
7616 print_end_stepping_range_reason (struct ui_out
*uiout
)
7618 /* For CLI-like interpreters, print nothing. */
7620 if (uiout
->is_mi_like_p ())
7622 uiout
->field_string ("reason",
7623 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
7628 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7630 annotate_signalled ();
7631 if (uiout
->is_mi_like_p ())
7633 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
7634 uiout
->text ("\nProgram terminated with signal ");
7635 annotate_signal_name ();
7636 uiout
->field_string ("signal-name",
7637 gdb_signal_to_name (siggnal
));
7638 annotate_signal_name_end ();
7640 annotate_signal_string ();
7641 uiout
->field_string ("signal-meaning",
7642 gdb_signal_to_string (siggnal
));
7643 annotate_signal_string_end ();
7644 uiout
->text (".\n");
7645 uiout
->text ("The program no longer exists.\n");
7649 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
7651 struct inferior
*inf
= current_inferior ();
7652 std::string pidstr
= target_pid_to_str (ptid_t (inf
->pid
));
7654 annotate_exited (exitstatus
);
7657 if (uiout
->is_mi_like_p ())
7658 uiout
->field_string ("reason", async_reason_lookup (EXEC_ASYNC_EXITED
));
7659 std::string exit_code_str
7660 = string_printf ("0%o", (unsigned int) exitstatus
);
7661 uiout
->message ("[Inferior %s (%s) exited with code %pF]\n",
7662 plongest (inf
->num
), pidstr
.c_str (),
7663 string_field ("exit-code", exit_code_str
.c_str ()));
7667 if (uiout
->is_mi_like_p ())
7669 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
7670 uiout
->message ("[Inferior %s (%s) exited normally]\n",
7671 plongest (inf
->num
), pidstr
.c_str ());
7675 /* Some targets/architectures can do extra processing/display of
7676 segmentation faults. E.g., Intel MPX boundary faults.
7677 Call the architecture dependent function to handle the fault. */
7680 handle_segmentation_fault (struct ui_out
*uiout
)
7682 struct regcache
*regcache
= get_current_regcache ();
7683 struct gdbarch
*gdbarch
= regcache
->arch ();
7685 if (gdbarch_handle_segmentation_fault_p (gdbarch
))
7686 gdbarch_handle_segmentation_fault (gdbarch
, uiout
);
7690 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7692 struct thread_info
*thr
= inferior_thread ();
7696 if (uiout
->is_mi_like_p ())
7698 else if (show_thread_that_caused_stop ())
7702 uiout
->text ("\nThread ");
7703 uiout
->field_string ("thread-id", print_thread_id (thr
));
7705 name
= thr
->name
!= NULL
? thr
->name
: target_thread_name (thr
);
7708 uiout
->text (" \"");
7709 uiout
->field_string ("name", name
);
7714 uiout
->text ("\nProgram");
7716 if (siggnal
== GDB_SIGNAL_0
&& !uiout
->is_mi_like_p ())
7717 uiout
->text (" stopped");
7720 uiout
->text (" received signal ");
7721 annotate_signal_name ();
7722 if (uiout
->is_mi_like_p ())
7724 ("reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
7725 uiout
->field_string ("signal-name", gdb_signal_to_name (siggnal
));
7726 annotate_signal_name_end ();
7728 annotate_signal_string ();
7729 uiout
->field_string ("signal-meaning", gdb_signal_to_string (siggnal
));
7731 if (siggnal
== GDB_SIGNAL_SEGV
)
7732 handle_segmentation_fault (uiout
);
7734 annotate_signal_string_end ();
7736 uiout
->text (".\n");
7740 print_no_history_reason (struct ui_out
*uiout
)
7742 uiout
->text ("\nNo more reverse-execution history.\n");
7745 /* Print current location without a level number, if we have changed
7746 functions or hit a breakpoint. Print source line if we have one.
7747 bpstat_print contains the logic deciding in detail what to print,
7748 based on the event(s) that just occurred. */
7751 print_stop_location (struct target_waitstatus
*ws
)
7754 enum print_what source_flag
;
7755 int do_frame_printing
= 1;
7756 struct thread_info
*tp
= inferior_thread ();
7758 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
7762 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
7763 should) carry around the function and does (or should) use
7764 that when doing a frame comparison. */
7765 if (tp
->control
.stop_step
7766 && frame_id_eq (tp
->control
.step_frame_id
,
7767 get_frame_id (get_current_frame ()))
7768 && (tp
->control
.step_start_function
7769 == find_pc_function (tp
->suspend
.stop_pc
)))
7771 /* Finished step, just print source line. */
7772 source_flag
= SRC_LINE
;
7776 /* Print location and source line. */
7777 source_flag
= SRC_AND_LOC
;
7780 case PRINT_SRC_AND_LOC
:
7781 /* Print location and source line. */
7782 source_flag
= SRC_AND_LOC
;
7784 case PRINT_SRC_ONLY
:
7785 source_flag
= SRC_LINE
;
7788 /* Something bogus. */
7789 source_flag
= SRC_LINE
;
7790 do_frame_printing
= 0;
7793 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
7796 /* The behavior of this routine with respect to the source
7798 SRC_LINE: Print only source line
7799 LOCATION: Print only location
7800 SRC_AND_LOC: Print location and source line. */
7801 if (do_frame_printing
)
7802 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
7808 print_stop_event (struct ui_out
*uiout
, bool displays
)
7810 struct target_waitstatus last
;
7812 struct thread_info
*tp
;
7814 get_last_target_status (&last_ptid
, &last
);
7817 scoped_restore save_uiout
= make_scoped_restore (¤t_uiout
, uiout
);
7819 print_stop_location (&last
);
7821 /* Display the auto-display expressions. */
7826 tp
= inferior_thread ();
7827 if (tp
->thread_fsm
!= NULL
7828 && tp
->thread_fsm
->finished_p ())
7830 struct return_value_info
*rv
;
7832 rv
= tp
->thread_fsm
->return_value ();
7834 print_return_value (uiout
, rv
);
7841 maybe_remove_breakpoints (void)
7843 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
7845 if (remove_breakpoints ())
7847 target_terminal::ours_for_output ();
7848 printf_filtered (_("Cannot remove breakpoints because "
7849 "program is no longer writable.\nFurther "
7850 "execution is probably impossible.\n"));
7855 /* The execution context that just caused a normal stop. */
7862 DISABLE_COPY_AND_ASSIGN (stop_context
);
7864 bool changed () const;
7869 /* The event PTID. */
7873 /* If stopp for a thread event, this is the thread that caused the
7875 struct thread_info
*thread
;
7877 /* The inferior that caused the stop. */
7881 /* Initializes a new stop context. If stopped for a thread event, this
7882 takes a strong reference to the thread. */
7884 stop_context::stop_context ()
7886 stop_id
= get_stop_id ();
7887 ptid
= inferior_ptid
;
7888 inf_num
= current_inferior ()->num
;
7890 if (inferior_ptid
!= null_ptid
)
7892 /* Take a strong reference so that the thread can't be deleted
7894 thread
= inferior_thread ();
7901 /* Release a stop context previously created with save_stop_context.
7902 Releases the strong reference to the thread as well. */
7904 stop_context::~stop_context ()
7910 /* Return true if the current context no longer matches the saved stop
7914 stop_context::changed () const
7916 if (ptid
!= inferior_ptid
)
7918 if (inf_num
!= current_inferior ()->num
)
7920 if (thread
!= NULL
&& thread
->state
!= THREAD_STOPPED
)
7922 if (get_stop_id () != stop_id
)
7932 struct target_waitstatus last
;
7935 get_last_target_status (&last_ptid
, &last
);
7939 /* If an exception is thrown from this point on, make sure to
7940 propagate GDB's knowledge of the executing state to the
7941 frontend/user running state. A QUIT is an easy exception to see
7942 here, so do this before any filtered output. */
7944 gdb::optional
<scoped_finish_thread_state
> maybe_finish_thread_state
;
7947 maybe_finish_thread_state
.emplace (minus_one_ptid
);
7948 else if (last
.kind
== TARGET_WAITKIND_SIGNALLED
7949 || last
.kind
== TARGET_WAITKIND_EXITED
)
7951 /* On some targets, we may still have live threads in the
7952 inferior when we get a process exit event. E.g., for
7953 "checkpoint", when the current checkpoint/fork exits,
7954 linux-fork.c automatically switches to another fork from
7955 within target_mourn_inferior. */
7956 if (inferior_ptid
!= null_ptid
)
7957 maybe_finish_thread_state
.emplace (ptid_t (inferior_ptid
.pid ()));
7959 else if (last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
7960 maybe_finish_thread_state
.emplace (inferior_ptid
);
7962 /* As we're presenting a stop, and potentially removing breakpoints,
7963 update the thread list so we can tell whether there are threads
7964 running on the target. With target remote, for example, we can
7965 only learn about new threads when we explicitly update the thread
7966 list. Do this before notifying the interpreters about signal
7967 stops, end of stepping ranges, etc., so that the "new thread"
7968 output is emitted before e.g., "Program received signal FOO",
7969 instead of after. */
7970 update_thread_list ();
7972 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
7973 gdb::observers::signal_received
.notify (inferior_thread ()->suspend
.stop_signal
);
7975 /* As with the notification of thread events, we want to delay
7976 notifying the user that we've switched thread context until
7977 the inferior actually stops.
7979 There's no point in saying anything if the inferior has exited.
7980 Note that SIGNALLED here means "exited with a signal", not
7981 "received a signal".
7983 Also skip saying anything in non-stop mode. In that mode, as we
7984 don't want GDB to switch threads behind the user's back, to avoid
7985 races where the user is typing a command to apply to thread x,
7986 but GDB switches to thread y before the user finishes entering
7987 the command, fetch_inferior_event installs a cleanup to restore
7988 the current thread back to the thread the user had selected right
7989 after this event is handled, so we're not really switching, only
7990 informing of a stop. */
7992 && previous_inferior_ptid
!= inferior_ptid
7993 && target_has_execution
7994 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
7995 && last
.kind
!= TARGET_WAITKIND_EXITED
7996 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
7998 SWITCH_THRU_ALL_UIS ()
8000 target_terminal::ours_for_output ();
8001 printf_filtered (_("[Switching to %s]\n"),
8002 target_pid_to_str (inferior_ptid
).c_str ());
8003 annotate_thread_changed ();
8005 previous_inferior_ptid
= inferior_ptid
;
8008 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
8010 SWITCH_THRU_ALL_UIS ()
8011 if (current_ui
->prompt_state
== PROMPT_BLOCKED
)
8013 target_terminal::ours_for_output ();
8014 printf_filtered (_("No unwaited-for children left.\n"));
8018 /* Note: this depends on the update_thread_list call above. */
8019 maybe_remove_breakpoints ();
8021 /* If an auto-display called a function and that got a signal,
8022 delete that auto-display to avoid an infinite recursion. */
8024 if (stopped_by_random_signal
)
8025 disable_current_display ();
8027 SWITCH_THRU_ALL_UIS ()
8029 async_enable_stdin ();
8032 /* Let the user/frontend see the threads as stopped. */
8033 maybe_finish_thread_state
.reset ();
8035 /* Select innermost stack frame - i.e., current frame is frame 0,
8036 and current location is based on that. Handle the case where the
8037 dummy call is returning after being stopped. E.g. the dummy call
8038 previously hit a breakpoint. (If the dummy call returns
8039 normally, we won't reach here.) Do this before the stop hook is
8040 run, so that it doesn't get to see the temporary dummy frame,
8041 which is not where we'll present the stop. */
8042 if (has_stack_frames ())
8044 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
8046 /* Pop the empty frame that contains the stack dummy. This
8047 also restores inferior state prior to the call (struct
8048 infcall_suspend_state). */
8049 struct frame_info
*frame
= get_current_frame ();
8051 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
8053 /* frame_pop calls reinit_frame_cache as the last thing it
8054 does which means there's now no selected frame. */
8057 select_frame (get_current_frame ());
8059 /* Set the current source location. */
8060 set_current_sal_from_frame (get_current_frame ());
8063 /* Look up the hook_stop and run it (CLI internally handles problem
8064 of stop_command's pre-hook not existing). */
8065 if (stop_command
!= NULL
)
8067 stop_context saved_context
;
8071 execute_cmd_pre_hook (stop_command
);
8073 catch (const gdb_exception
&ex
)
8075 exception_fprintf (gdb_stderr
, ex
,
8076 "Error while running hook_stop:\n");
8079 /* If the stop hook resumes the target, then there's no point in
8080 trying to notify about the previous stop; its context is
8081 gone. Likewise if the command switches thread or inferior --
8082 the observers would print a stop for the wrong
8084 if (saved_context
.changed ())
8088 /* Notify observers about the stop. This is where the interpreters
8089 print the stop event. */
8090 if (inferior_ptid
!= null_ptid
)
8091 gdb::observers::normal_stop
.notify (inferior_thread ()->control
.stop_bpstat
,
8094 gdb::observers::normal_stop
.notify (NULL
, stop_print_frame
);
8096 annotate_stopped ();
8098 if (target_has_execution
)
8100 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
8101 && last
.kind
!= TARGET_WAITKIND_EXITED
8102 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8103 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8104 Delete any breakpoint that is to be deleted at the next stop. */
8105 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
8108 /* Try to get rid of automatically added inferiors that are no
8109 longer needed. Keeping those around slows down things linearly.
8110 Note that this never removes the current inferior. */
8117 signal_stop_state (int signo
)
8119 return signal_stop
[signo
];
8123 signal_print_state (int signo
)
8125 return signal_print
[signo
];
8129 signal_pass_state (int signo
)
8131 return signal_program
[signo
];
8135 signal_cache_update (int signo
)
8139 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
8140 signal_cache_update (signo
);
8145 signal_pass
[signo
] = (signal_stop
[signo
] == 0
8146 && signal_print
[signo
] == 0
8147 && signal_program
[signo
] == 1
8148 && signal_catch
[signo
] == 0);
8152 signal_stop_update (int signo
, int state
)
8154 int ret
= signal_stop
[signo
];
8156 signal_stop
[signo
] = state
;
8157 signal_cache_update (signo
);
8162 signal_print_update (int signo
, int state
)
8164 int ret
= signal_print
[signo
];
8166 signal_print
[signo
] = state
;
8167 signal_cache_update (signo
);
8172 signal_pass_update (int signo
, int state
)
8174 int ret
= signal_program
[signo
];
8176 signal_program
[signo
] = state
;
8177 signal_cache_update (signo
);
8181 /* Update the global 'signal_catch' from INFO and notify the
8185 signal_catch_update (const unsigned int *info
)
8189 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
8190 signal_catch
[i
] = info
[i
] > 0;
8191 signal_cache_update (-1);
8192 target_pass_signals (signal_pass
);
8196 sig_print_header (void)
8198 printf_filtered (_("Signal Stop\tPrint\tPass "
8199 "to program\tDescription\n"));
8203 sig_print_info (enum gdb_signal oursig
)
8205 const char *name
= gdb_signal_to_name (oursig
);
8206 int name_padding
= 13 - strlen (name
);
8208 if (name_padding
<= 0)
8211 printf_filtered ("%s", name
);
8212 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
8213 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
8214 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
8215 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
8216 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
8219 /* Specify how various signals in the inferior should be handled. */
8222 handle_command (const char *args
, int from_tty
)
8224 int digits
, wordlen
;
8225 int sigfirst
, siglast
;
8226 enum gdb_signal oursig
;
8231 error_no_arg (_("signal to handle"));
8234 /* Allocate and zero an array of flags for which signals to handle. */
8236 const size_t nsigs
= GDB_SIGNAL_LAST
;
8237 unsigned char sigs
[nsigs
] {};
8239 /* Break the command line up into args. */
8241 gdb_argv
built_argv (args
);
8243 /* Walk through the args, looking for signal oursigs, signal names, and
8244 actions. Signal numbers and signal names may be interspersed with
8245 actions, with the actions being performed for all signals cumulatively
8246 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8248 for (char *arg
: built_argv
)
8250 wordlen
= strlen (arg
);
8251 for (digits
= 0; isdigit (arg
[digits
]); digits
++)
8255 sigfirst
= siglast
= -1;
8257 if (wordlen
>= 1 && !strncmp (arg
, "all", wordlen
))
8259 /* Apply action to all signals except those used by the
8260 debugger. Silently skip those. */
8263 siglast
= nsigs
- 1;
8265 else if (wordlen
>= 1 && !strncmp (arg
, "stop", wordlen
))
8267 SET_SIGS (nsigs
, sigs
, signal_stop
);
8268 SET_SIGS (nsigs
, sigs
, signal_print
);
8270 else if (wordlen
>= 1 && !strncmp (arg
, "ignore", wordlen
))
8272 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8274 else if (wordlen
>= 2 && !strncmp (arg
, "print", wordlen
))
8276 SET_SIGS (nsigs
, sigs
, signal_print
);
8278 else if (wordlen
>= 2 && !strncmp (arg
, "pass", wordlen
))
8280 SET_SIGS (nsigs
, sigs
, signal_program
);
8282 else if (wordlen
>= 3 && !strncmp (arg
, "nostop", wordlen
))
8284 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8286 else if (wordlen
>= 3 && !strncmp (arg
, "noignore", wordlen
))
8288 SET_SIGS (nsigs
, sigs
, signal_program
);
8290 else if (wordlen
>= 4 && !strncmp (arg
, "noprint", wordlen
))
8292 UNSET_SIGS (nsigs
, sigs
, signal_print
);
8293 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8295 else if (wordlen
>= 4 && !strncmp (arg
, "nopass", wordlen
))
8297 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8299 else if (digits
> 0)
8301 /* It is numeric. The numeric signal refers to our own
8302 internal signal numbering from target.h, not to host/target
8303 signal number. This is a feature; users really should be
8304 using symbolic names anyway, and the common ones like
8305 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8307 sigfirst
= siglast
= (int)
8308 gdb_signal_from_command (atoi (arg
));
8309 if (arg
[digits
] == '-')
8312 gdb_signal_from_command (atoi (arg
+ digits
+ 1));
8314 if (sigfirst
> siglast
)
8316 /* Bet he didn't figure we'd think of this case... */
8317 std::swap (sigfirst
, siglast
);
8322 oursig
= gdb_signal_from_name (arg
);
8323 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
8325 sigfirst
= siglast
= (int) oursig
;
8329 /* Not a number and not a recognized flag word => complain. */
8330 error (_("Unrecognized or ambiguous flag word: \"%s\"."), arg
);
8334 /* If any signal numbers or symbol names were found, set flags for
8335 which signals to apply actions to. */
8337 for (int signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
8339 switch ((enum gdb_signal
) signum
)
8341 case GDB_SIGNAL_TRAP
:
8342 case GDB_SIGNAL_INT
:
8343 if (!allsigs
&& !sigs
[signum
])
8345 if (query (_("%s is used by the debugger.\n\
8346 Are you sure you want to change it? "),
8347 gdb_signal_to_name ((enum gdb_signal
) signum
)))
8352 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8356 case GDB_SIGNAL_DEFAULT
:
8357 case GDB_SIGNAL_UNKNOWN
:
8358 /* Make sure that "all" doesn't print these. */
8367 for (int signum
= 0; signum
< nsigs
; signum
++)
8370 signal_cache_update (-1);
8371 target_pass_signals (signal_pass
);
8372 target_program_signals (signal_program
);
8376 /* Show the results. */
8377 sig_print_header ();
8378 for (; signum
< nsigs
; signum
++)
8380 sig_print_info ((enum gdb_signal
) signum
);
8387 /* Complete the "handle" command. */
8390 handle_completer (struct cmd_list_element
*ignore
,
8391 completion_tracker
&tracker
,
8392 const char *text
, const char *word
)
8394 static const char * const keywords
[] =
8408 signal_completer (ignore
, tracker
, text
, word
);
8409 complete_on_enum (tracker
, keywords
, word
, word
);
8413 gdb_signal_from_command (int num
)
8415 if (num
>= 1 && num
<= 15)
8416 return (enum gdb_signal
) num
;
8417 error (_("Only signals 1-15 are valid as numeric signals.\n\
8418 Use \"info signals\" for a list of symbolic signals."));
8421 /* Print current contents of the tables set by the handle command.
8422 It is possible we should just be printing signals actually used
8423 by the current target (but for things to work right when switching
8424 targets, all signals should be in the signal tables). */
8427 info_signals_command (const char *signum_exp
, int from_tty
)
8429 enum gdb_signal oursig
;
8431 sig_print_header ();
8435 /* First see if this is a symbol name. */
8436 oursig
= gdb_signal_from_name (signum_exp
);
8437 if (oursig
== GDB_SIGNAL_UNKNOWN
)
8439 /* No, try numeric. */
8441 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
8443 sig_print_info (oursig
);
8447 printf_filtered ("\n");
8448 /* These ugly casts brought to you by the native VAX compiler. */
8449 for (oursig
= GDB_SIGNAL_FIRST
;
8450 (int) oursig
< (int) GDB_SIGNAL_LAST
;
8451 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
8455 if (oursig
!= GDB_SIGNAL_UNKNOWN
8456 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
8457 sig_print_info (oursig
);
8460 printf_filtered (_("\nUse the \"handle\" command "
8461 "to change these tables.\n"));
8464 /* The $_siginfo convenience variable is a bit special. We don't know
8465 for sure the type of the value until we actually have a chance to
8466 fetch the data. The type can change depending on gdbarch, so it is
8467 also dependent on which thread you have selected.
8469 1. making $_siginfo be an internalvar that creates a new value on
8472 2. making the value of $_siginfo be an lval_computed value. */
8474 /* This function implements the lval_computed support for reading a
8478 siginfo_value_read (struct value
*v
)
8480 LONGEST transferred
;
8482 /* If we can access registers, so can we access $_siginfo. Likewise
8484 validate_registers_access ();
8487 target_read (current_top_target (), TARGET_OBJECT_SIGNAL_INFO
,
8489 value_contents_all_raw (v
),
8491 TYPE_LENGTH (value_type (v
)));
8493 if (transferred
!= TYPE_LENGTH (value_type (v
)))
8494 error (_("Unable to read siginfo"));
8497 /* This function implements the lval_computed support for writing a
8501 siginfo_value_write (struct value
*v
, struct value
*fromval
)
8503 LONGEST transferred
;
8505 /* If we can access registers, so can we access $_siginfo. Likewise
8507 validate_registers_access ();
8509 transferred
= target_write (current_top_target (),
8510 TARGET_OBJECT_SIGNAL_INFO
,
8512 value_contents_all_raw (fromval
),
8514 TYPE_LENGTH (value_type (fromval
)));
8516 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
8517 error (_("Unable to write siginfo"));
8520 static const struct lval_funcs siginfo_value_funcs
=
8526 /* Return a new value with the correct type for the siginfo object of
8527 the current thread using architecture GDBARCH. Return a void value
8528 if there's no object available. */
8530 static struct value
*
8531 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
8534 if (target_has_stack
8535 && inferior_ptid
!= null_ptid
8536 && gdbarch_get_siginfo_type_p (gdbarch
))
8538 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8540 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
8543 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
8547 /* infcall_suspend_state contains state about the program itself like its
8548 registers and any signal it received when it last stopped.
8549 This state must be restored regardless of how the inferior function call
8550 ends (either successfully, or after it hits a breakpoint or signal)
8551 if the program is to properly continue where it left off. */
8553 class infcall_suspend_state
8556 /* Capture state from GDBARCH, TP, and REGCACHE that must be restored
8557 once the inferior function call has finished. */
8558 infcall_suspend_state (struct gdbarch
*gdbarch
,
8559 const struct thread_info
*tp
,
8560 struct regcache
*regcache
)
8561 : m_thread_suspend (tp
->suspend
),
8562 m_registers (new readonly_detached_regcache (*regcache
))
8564 gdb::unique_xmalloc_ptr
<gdb_byte
> siginfo_data
;
8566 if (gdbarch_get_siginfo_type_p (gdbarch
))
8568 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8569 size_t len
= TYPE_LENGTH (type
);
8571 siginfo_data
.reset ((gdb_byte
*) xmalloc (len
));
8573 if (target_read (current_top_target (), TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8574 siginfo_data
.get (), 0, len
) != len
)
8576 /* Errors ignored. */
8577 siginfo_data
.reset (nullptr);
8583 m_siginfo_gdbarch
= gdbarch
;
8584 m_siginfo_data
= std::move (siginfo_data
);
8588 /* Return a pointer to the stored register state. */
8590 readonly_detached_regcache
*registers () const
8592 return m_registers
.get ();
8595 /* Restores the stored state into GDBARCH, TP, and REGCACHE. */
8597 void restore (struct gdbarch
*gdbarch
,
8598 struct thread_info
*tp
,
8599 struct regcache
*regcache
) const
8601 tp
->suspend
= m_thread_suspend
;
8603 if (m_siginfo_gdbarch
== gdbarch
)
8605 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8607 /* Errors ignored. */
8608 target_write (current_top_target (), TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8609 m_siginfo_data
.get (), 0, TYPE_LENGTH (type
));
8612 /* The inferior can be gone if the user types "print exit(0)"
8613 (and perhaps other times). */
8614 if (target_has_execution
)
8615 /* NB: The register write goes through to the target. */
8616 regcache
->restore (registers ());
8620 /* How the current thread stopped before the inferior function call was
8622 struct thread_suspend_state m_thread_suspend
;
8624 /* The registers before the inferior function call was executed. */
8625 std::unique_ptr
<readonly_detached_regcache
> m_registers
;
8627 /* Format of SIGINFO_DATA or NULL if it is not present. */
8628 struct gdbarch
*m_siginfo_gdbarch
= nullptr;
8630 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
8631 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
8632 content would be invalid. */
8633 gdb::unique_xmalloc_ptr
<gdb_byte
> m_siginfo_data
;
8636 infcall_suspend_state_up
8637 save_infcall_suspend_state ()
8639 struct thread_info
*tp
= inferior_thread ();
8640 struct regcache
*regcache
= get_current_regcache ();
8641 struct gdbarch
*gdbarch
= regcache
->arch ();
8643 infcall_suspend_state_up inf_state
8644 (new struct infcall_suspend_state (gdbarch
, tp
, regcache
));
8646 /* Having saved the current state, adjust the thread state, discarding
8647 any stop signal information. The stop signal is not useful when
8648 starting an inferior function call, and run_inferior_call will not use
8649 the signal due to its `proceed' call with GDB_SIGNAL_0. */
8650 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
8655 /* Restore inferior session state to INF_STATE. */
8658 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8660 struct thread_info
*tp
= inferior_thread ();
8661 struct regcache
*regcache
= get_current_regcache ();
8662 struct gdbarch
*gdbarch
= regcache
->arch ();
8664 inf_state
->restore (gdbarch
, tp
, regcache
);
8665 discard_infcall_suspend_state (inf_state
);
8669 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8674 readonly_detached_regcache
*
8675 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
8677 return inf_state
->registers ();
8680 /* infcall_control_state contains state regarding gdb's control of the
8681 inferior itself like stepping control. It also contains session state like
8682 the user's currently selected frame. */
8684 struct infcall_control_state
8686 struct thread_control_state thread_control
;
8687 struct inferior_control_state inferior_control
;
8690 enum stop_stack_kind stop_stack_dummy
= STOP_NONE
;
8691 int stopped_by_random_signal
= 0;
8693 /* ID if the selected frame when the inferior function call was made. */
8694 struct frame_id selected_frame_id
{};
8697 /* Save all of the information associated with the inferior<==>gdb
8700 infcall_control_state_up
8701 save_infcall_control_state ()
8703 infcall_control_state_up
inf_status (new struct infcall_control_state
);
8704 struct thread_info
*tp
= inferior_thread ();
8705 struct inferior
*inf
= current_inferior ();
8707 inf_status
->thread_control
= tp
->control
;
8708 inf_status
->inferior_control
= inf
->control
;
8710 tp
->control
.step_resume_breakpoint
= NULL
;
8711 tp
->control
.exception_resume_breakpoint
= NULL
;
8713 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
8714 chain. If caller's caller is walking the chain, they'll be happier if we
8715 hand them back the original chain when restore_infcall_control_state is
8717 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
8720 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
8721 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
8723 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
8729 restore_selected_frame (const frame_id
&fid
)
8731 frame_info
*frame
= frame_find_by_id (fid
);
8733 /* If inf_status->selected_frame_id is NULL, there was no previously
8737 warning (_("Unable to restore previously selected frame."));
8741 select_frame (frame
);
8744 /* Restore inferior session state to INF_STATUS. */
8747 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
8749 struct thread_info
*tp
= inferior_thread ();
8750 struct inferior
*inf
= current_inferior ();
8752 if (tp
->control
.step_resume_breakpoint
)
8753 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
8755 if (tp
->control
.exception_resume_breakpoint
)
8756 tp
->control
.exception_resume_breakpoint
->disposition
8757 = disp_del_at_next_stop
;
8759 /* Handle the bpstat_copy of the chain. */
8760 bpstat_clear (&tp
->control
.stop_bpstat
);
8762 tp
->control
= inf_status
->thread_control
;
8763 inf
->control
= inf_status
->inferior_control
;
8766 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
8767 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
8769 if (target_has_stack
)
8771 /* The point of the try/catch is that if the stack is clobbered,
8772 walking the stack might encounter a garbage pointer and
8773 error() trying to dereference it. */
8776 restore_selected_frame (inf_status
->selected_frame_id
);
8778 catch (const gdb_exception_error
&ex
)
8780 exception_fprintf (gdb_stderr
, ex
,
8781 "Unable to restore previously selected frame:\n");
8782 /* Error in restoring the selected frame. Select the
8784 select_frame (get_current_frame ());
8792 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
8794 if (inf_status
->thread_control
.step_resume_breakpoint
)
8795 inf_status
->thread_control
.step_resume_breakpoint
->disposition
8796 = disp_del_at_next_stop
;
8798 if (inf_status
->thread_control
.exception_resume_breakpoint
)
8799 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
8800 = disp_del_at_next_stop
;
8802 /* See save_infcall_control_state for info on stop_bpstat. */
8803 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
8811 clear_exit_convenience_vars (void)
8813 clear_internalvar (lookup_internalvar ("_exitsignal"));
8814 clear_internalvar (lookup_internalvar ("_exitcode"));
8818 /* User interface for reverse debugging:
8819 Set exec-direction / show exec-direction commands
8820 (returns error unless target implements to_set_exec_direction method). */
8822 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
8823 static const char exec_forward
[] = "forward";
8824 static const char exec_reverse
[] = "reverse";
8825 static const char *exec_direction
= exec_forward
;
8826 static const char *const exec_direction_names
[] = {
8833 set_exec_direction_func (const char *args
, int from_tty
,
8834 struct cmd_list_element
*cmd
)
8836 if (target_can_execute_reverse
)
8838 if (!strcmp (exec_direction
, exec_forward
))
8839 execution_direction
= EXEC_FORWARD
;
8840 else if (!strcmp (exec_direction
, exec_reverse
))
8841 execution_direction
= EXEC_REVERSE
;
8845 exec_direction
= exec_forward
;
8846 error (_("Target does not support this operation."));
8851 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
8852 struct cmd_list_element
*cmd
, const char *value
)
8854 switch (execution_direction
) {
8856 fprintf_filtered (out
, _("Forward.\n"));
8859 fprintf_filtered (out
, _("Reverse.\n"));
8862 internal_error (__FILE__
, __LINE__
,
8863 _("bogus execution_direction value: %d"),
8864 (int) execution_direction
);
8869 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
8870 struct cmd_list_element
*c
, const char *value
)
8872 fprintf_filtered (file
, _("Resuming the execution of threads "
8873 "of all processes is %s.\n"), value
);
8876 /* Implementation of `siginfo' variable. */
8878 static const struct internalvar_funcs siginfo_funcs
=
8885 /* Callback for infrun's target events source. This is marked when a
8886 thread has a pending status to process. */
8889 infrun_async_inferior_event_handler (gdb_client_data data
)
8891 inferior_event_handler (INF_REG_EVENT
, NULL
);
8895 _initialize_infrun (void)
8897 struct cmd_list_element
*c
;
8899 /* Register extra event sources in the event loop. */
8900 infrun_async_inferior_event_token
8901 = create_async_event_handler (infrun_async_inferior_event_handler
, NULL
);
8903 add_info ("signals", info_signals_command
, _("\
8904 What debugger does when program gets various signals.\n\
8905 Specify a signal as argument to print info on that signal only."));
8906 add_info_alias ("handle", "signals", 0);
8908 c
= add_com ("handle", class_run
, handle_command
, _("\
8909 Specify how to handle signals.\n\
8910 Usage: handle SIGNAL [ACTIONS]\n\
8911 Args are signals and actions to apply to those signals.\n\
8912 If no actions are specified, the current settings for the specified signals\n\
8913 will be displayed instead.\n\
8915 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
8916 from 1-15 are allowed for compatibility with old versions of GDB.\n\
8917 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
8918 The special arg \"all\" is recognized to mean all signals except those\n\
8919 used by the debugger, typically SIGTRAP and SIGINT.\n\
8921 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
8922 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
8923 Stop means reenter debugger if this signal happens (implies print).\n\
8924 Print means print a message if this signal happens.\n\
8925 Pass means let program see this signal; otherwise program doesn't know.\n\
8926 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
8927 Pass and Stop may be combined.\n\
8929 Multiple signals may be specified. Signal numbers and signal names\n\
8930 may be interspersed with actions, with the actions being performed for\n\
8931 all signals cumulatively specified."));
8932 set_cmd_completer (c
, handle_completer
);
8935 stop_command
= add_cmd ("stop", class_obscure
,
8936 not_just_help_class_command
, _("\
8937 There is no `stop' command, but you can set a hook on `stop'.\n\
8938 This allows you to set a list of commands to be run each time execution\n\
8939 of the program stops."), &cmdlist
);
8941 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
8942 Set inferior debugging."), _("\
8943 Show inferior debugging."), _("\
8944 When non-zero, inferior specific debugging is enabled."),
8947 &setdebuglist
, &showdebuglist
);
8949 add_setshow_boolean_cmd ("displaced", class_maintenance
,
8950 &debug_displaced
, _("\
8951 Set displaced stepping debugging."), _("\
8952 Show displaced stepping debugging."), _("\
8953 When non-zero, displaced stepping specific debugging is enabled."),
8955 show_debug_displaced
,
8956 &setdebuglist
, &showdebuglist
);
8958 add_setshow_boolean_cmd ("non-stop", no_class
,
8960 Set whether gdb controls the inferior in non-stop mode."), _("\
8961 Show whether gdb controls the inferior in non-stop mode."), _("\
8962 When debugging a multi-threaded program and this setting is\n\
8963 off (the default, also called all-stop mode), when one thread stops\n\
8964 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
8965 all other threads in the program while you interact with the thread of\n\
8966 interest. When you continue or step a thread, you can allow the other\n\
8967 threads to run, or have them remain stopped, but while you inspect any\n\
8968 thread's state, all threads stop.\n\
8970 In non-stop mode, when one thread stops, other threads can continue\n\
8971 to run freely. You'll be able to step each thread independently,\n\
8972 leave it stopped or free to run as needed."),
8978 for (size_t i
= 0; i
< GDB_SIGNAL_LAST
; i
++)
8981 signal_print
[i
] = 1;
8982 signal_program
[i
] = 1;
8983 signal_catch
[i
] = 0;
8986 /* Signals caused by debugger's own actions should not be given to
8987 the program afterwards.
8989 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
8990 explicitly specifies that it should be delivered to the target
8991 program. Typically, that would occur when a user is debugging a
8992 target monitor on a simulator: the target monitor sets a
8993 breakpoint; the simulator encounters this breakpoint and halts
8994 the simulation handing control to GDB; GDB, noting that the stop
8995 address doesn't map to any known breakpoint, returns control back
8996 to the simulator; the simulator then delivers the hardware
8997 equivalent of a GDB_SIGNAL_TRAP to the program being
8999 signal_program
[GDB_SIGNAL_TRAP
] = 0;
9000 signal_program
[GDB_SIGNAL_INT
] = 0;
9002 /* Signals that are not errors should not normally enter the debugger. */
9003 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
9004 signal_print
[GDB_SIGNAL_ALRM
] = 0;
9005 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
9006 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
9007 signal_stop
[GDB_SIGNAL_PROF
] = 0;
9008 signal_print
[GDB_SIGNAL_PROF
] = 0;
9009 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
9010 signal_print
[GDB_SIGNAL_CHLD
] = 0;
9011 signal_stop
[GDB_SIGNAL_IO
] = 0;
9012 signal_print
[GDB_SIGNAL_IO
] = 0;
9013 signal_stop
[GDB_SIGNAL_POLL
] = 0;
9014 signal_print
[GDB_SIGNAL_POLL
] = 0;
9015 signal_stop
[GDB_SIGNAL_URG
] = 0;
9016 signal_print
[GDB_SIGNAL_URG
] = 0;
9017 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
9018 signal_print
[GDB_SIGNAL_WINCH
] = 0;
9019 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
9020 signal_print
[GDB_SIGNAL_PRIO
] = 0;
9022 /* These signals are used internally by user-level thread
9023 implementations. (See signal(5) on Solaris.) Like the above
9024 signals, a healthy program receives and handles them as part of
9025 its normal operation. */
9026 signal_stop
[GDB_SIGNAL_LWP
] = 0;
9027 signal_print
[GDB_SIGNAL_LWP
] = 0;
9028 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
9029 signal_print
[GDB_SIGNAL_WAITING
] = 0;
9030 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
9031 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
9032 signal_stop
[GDB_SIGNAL_LIBRT
] = 0;
9033 signal_print
[GDB_SIGNAL_LIBRT
] = 0;
9035 /* Update cached state. */
9036 signal_cache_update (-1);
9038 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
9039 &stop_on_solib_events
, _("\
9040 Set stopping for shared library events."), _("\
9041 Show stopping for shared library events."), _("\
9042 If nonzero, gdb will give control to the user when the dynamic linker\n\
9043 notifies gdb of shared library events. The most common event of interest\n\
9044 to the user would be loading/unloading of a new library."),
9045 set_stop_on_solib_events
,
9046 show_stop_on_solib_events
,
9047 &setlist
, &showlist
);
9049 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
9050 follow_fork_mode_kind_names
,
9051 &follow_fork_mode_string
, _("\
9052 Set debugger response to a program call of fork or vfork."), _("\
9053 Show debugger response to a program call of fork or vfork."), _("\
9054 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9055 parent - the original process is debugged after a fork\n\
9056 child - the new process is debugged after a fork\n\
9057 The unfollowed process will continue to run.\n\
9058 By default, the debugger will follow the parent process."),
9060 show_follow_fork_mode_string
,
9061 &setlist
, &showlist
);
9063 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
9064 follow_exec_mode_names
,
9065 &follow_exec_mode_string
, _("\
9066 Set debugger response to a program call of exec."), _("\
9067 Show debugger response to a program call of exec."), _("\
9068 An exec call replaces the program image of a process.\n\
9070 follow-exec-mode can be:\n\
9072 new - the debugger creates a new inferior and rebinds the process\n\
9073 to this new inferior. The program the process was running before\n\
9074 the exec call can be restarted afterwards by restarting the original\n\
9077 same - the debugger keeps the process bound to the same inferior.\n\
9078 The new executable image replaces the previous executable loaded in\n\
9079 the inferior. Restarting the inferior after the exec call restarts\n\
9080 the executable the process was running after the exec call.\n\
9082 By default, the debugger will use the same inferior."),
9084 show_follow_exec_mode_string
,
9085 &setlist
, &showlist
);
9087 add_setshow_enum_cmd ("scheduler-locking", class_run
,
9088 scheduler_enums
, &scheduler_mode
, _("\
9089 Set mode for locking scheduler during execution."), _("\
9090 Show mode for locking scheduler during execution."), _("\
9091 off == no locking (threads may preempt at any time)\n\
9092 on == full locking (no thread except the current thread may run)\n\
9093 This applies to both normal execution and replay mode.\n\
9094 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9095 In this mode, other threads may run during other commands.\n\
9096 This applies to both normal execution and replay mode.\n\
9097 replay == scheduler locked in replay mode and unlocked during normal execution."),
9098 set_schedlock_func
, /* traps on target vector */
9099 show_scheduler_mode
,
9100 &setlist
, &showlist
);
9102 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
9103 Set mode for resuming threads of all processes."), _("\
9104 Show mode for resuming threads of all processes."), _("\
9105 When on, execution commands (such as 'continue' or 'next') resume all\n\
9106 threads of all processes. When off (which is the default), execution\n\
9107 commands only resume the threads of the current process. The set of\n\
9108 threads that are resumed is further refined by the scheduler-locking\n\
9109 mode (see help set scheduler-locking)."),
9111 show_schedule_multiple
,
9112 &setlist
, &showlist
);
9114 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
9115 Set mode of the step operation."), _("\
9116 Show mode of the step operation."), _("\
9117 When set, doing a step over a function without debug line information\n\
9118 will stop at the first instruction of that function. Otherwise, the\n\
9119 function is skipped and the step command stops at a different source line."),
9121 show_step_stop_if_no_debug
,
9122 &setlist
, &showlist
);
9124 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
9125 &can_use_displaced_stepping
, _("\
9126 Set debugger's willingness to use displaced stepping."), _("\
9127 Show debugger's willingness to use displaced stepping."), _("\
9128 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9129 supported by the target architecture. If off, gdb will not use displaced\n\
9130 stepping to step over breakpoints, even if such is supported by the target\n\
9131 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9132 if the target architecture supports it and non-stop mode is active, but will not\n\
9133 use it in all-stop mode (see help set non-stop)."),
9135 show_can_use_displaced_stepping
,
9136 &setlist
, &showlist
);
9138 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
9139 &exec_direction
, _("Set direction of execution.\n\
9140 Options are 'forward' or 'reverse'."),
9141 _("Show direction of execution (forward/reverse)."),
9142 _("Tells gdb whether to execute forward or backward."),
9143 set_exec_direction_func
, show_exec_direction_func
,
9144 &setlist
, &showlist
);
9146 /* Set/show detach-on-fork: user-settable mode. */
9148 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
9149 Set whether gdb will detach the child of a fork."), _("\
9150 Show whether gdb will detach the child of a fork."), _("\
9151 Tells gdb whether to detach the child of a fork."),
9152 NULL
, NULL
, &setlist
, &showlist
);
9154 /* Set/show disable address space randomization mode. */
9156 add_setshow_boolean_cmd ("disable-randomization", class_support
,
9157 &disable_randomization
, _("\
9158 Set disabling of debuggee's virtual address space randomization."), _("\
9159 Show disabling of debuggee's virtual address space randomization."), _("\
9160 When this mode is on (which is the default), randomization of the virtual\n\
9161 address space is disabled. Standalone programs run with the randomization\n\
9162 enabled by default on some platforms."),
9163 &set_disable_randomization
,
9164 &show_disable_randomization
,
9165 &setlist
, &showlist
);
9167 /* ptid initializations */
9168 inferior_ptid
= null_ptid
;
9169 target_last_wait_ptid
= minus_one_ptid
;
9171 gdb::observers::thread_ptid_changed
.attach (infrun_thread_ptid_changed
);
9172 gdb::observers::thread_stop_requested
.attach (infrun_thread_stop_requested
);
9173 gdb::observers::thread_exit
.attach (infrun_thread_thread_exit
);
9174 gdb::observers::inferior_exit
.attach (infrun_inferior_exit
);
9176 /* Explicitly create without lookup, since that tries to create a
9177 value with a void typed value, and when we get here, gdbarch
9178 isn't initialized yet. At this point, we're quite sure there
9179 isn't another convenience variable of the same name. */
9180 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
9182 add_setshow_boolean_cmd ("observer", no_class
,
9183 &observer_mode_1
, _("\
9184 Set whether gdb controls the inferior in observer mode."), _("\
9185 Show whether gdb controls the inferior in observer mode."), _("\
9186 In observer mode, GDB can get data from the inferior, but not\n\
9187 affect its execution. Registers and memory may not be changed,\n\
9188 breakpoints may not be set, and the program cannot be interrupted\n\