1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2021 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/>. */
22 #include "displaced-stepping.h"
28 #include "breakpoint.h"
32 #include "target-connection.h"
33 #include "gdbthread.h"
40 #include "observable.h"
45 #include "mi/mi-common.h"
46 #include "event-top.h"
48 #include "record-full.h"
49 #include "inline-frame.h"
51 #include "tracepoint.h"
55 #include "completer.h"
56 #include "target-descriptions.h"
57 #include "target-dcache.h"
60 #include "gdbsupport/event-loop.h"
61 #include "thread-fsm.h"
62 #include "gdbsupport/enum-flags.h"
63 #include "progspace-and-thread.h"
64 #include "gdbsupport/gdb_optional.h"
65 #include "arch-utils.h"
66 #include "gdbsupport/scope-exit.h"
67 #include "gdbsupport/forward-scope-exit.h"
68 #include "gdbsupport/gdb_select.h"
69 #include <unordered_map>
70 #include "async-event.h"
71 #include "gdbsupport/selftest.h"
72 #include "scoped-mock-context.h"
73 #include "test-target.h"
74 #include "gdbsupport/common-debug.h"
76 /* Prototypes for local functions */
78 static void sig_print_info (enum gdb_signal
);
80 static void sig_print_header (void);
82 static void follow_inferior_reset_breakpoints (void);
84 static bool currently_stepping (struct thread_info
*tp
);
86 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*);
88 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
90 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
92 static bool maybe_software_singlestep (struct gdbarch
*gdbarch
);
94 static void resume (gdb_signal sig
);
96 static void wait_for_inferior (inferior
*inf
);
98 /* Asynchronous signal handler registered as event loop source for
99 when we have pending events ready to be passed to the core. */
100 static struct async_event_handler
*infrun_async_inferior_event_token
;
102 /* Stores whether infrun_async was previously enabled or disabled.
103 Starts off as -1, indicating "never enabled/disabled". */
104 static int infrun_is_async
= -1;
109 infrun_async (int enable
)
111 if (infrun_is_async
!= enable
)
113 infrun_is_async
= enable
;
115 infrun_debug_printf ("enable=%d", enable
);
118 mark_async_event_handler (infrun_async_inferior_event_token
);
120 clear_async_event_handler (infrun_async_inferior_event_token
);
127 mark_infrun_async_event_handler (void)
129 mark_async_event_handler (infrun_async_inferior_event_token
);
132 /* When set, stop the 'step' command if we enter a function which has
133 no line number information. The normal behavior is that we step
134 over such function. */
135 bool step_stop_if_no_debug
= false;
137 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
138 struct cmd_list_element
*c
, const char *value
)
140 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
143 /* proceed and normal_stop use this to notify the user when the
144 inferior stopped in a different thread than it had been running
147 static ptid_t previous_inferior_ptid
;
149 /* If set (default for legacy reasons), when following a fork, GDB
150 will detach from one of the fork branches, child or parent.
151 Exactly which branch is detached depends on 'set follow-fork-mode'
154 static bool detach_fork
= true;
156 bool debug_infrun
= false;
158 show_debug_infrun (struct ui_file
*file
, int from_tty
,
159 struct cmd_list_element
*c
, const char *value
)
161 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
164 /* Support for disabling address space randomization. */
166 bool disable_randomization
= true;
169 show_disable_randomization (struct ui_file
*file
, int from_tty
,
170 struct cmd_list_element
*c
, const char *value
)
172 if (target_supports_disable_randomization ())
173 fprintf_filtered (file
,
174 _("Disabling randomization of debuggee's "
175 "virtual address space is %s.\n"),
178 fputs_filtered (_("Disabling randomization of debuggee's "
179 "virtual address space is unsupported on\n"
180 "this platform.\n"), file
);
184 set_disable_randomization (const char *args
, int from_tty
,
185 struct cmd_list_element
*c
)
187 if (!target_supports_disable_randomization ())
188 error (_("Disabling randomization of debuggee's "
189 "virtual address space is unsupported on\n"
193 /* User interface for non-stop mode. */
195 bool non_stop
= false;
196 static bool non_stop_1
= false;
199 set_non_stop (const char *args
, int from_tty
,
200 struct cmd_list_element
*c
)
202 if (target_has_execution ())
204 non_stop_1
= non_stop
;
205 error (_("Cannot change this setting while the inferior is running."));
208 non_stop
= non_stop_1
;
212 show_non_stop (struct ui_file
*file
, int from_tty
,
213 struct cmd_list_element
*c
, const char *value
)
215 fprintf_filtered (file
,
216 _("Controlling the inferior in non-stop mode is %s.\n"),
220 /* "Observer mode" is somewhat like a more extreme version of
221 non-stop, in which all GDB operations that might affect the
222 target's execution have been disabled. */
224 static bool observer_mode
= false;
225 static bool observer_mode_1
= false;
228 set_observer_mode (const char *args
, int from_tty
,
229 struct cmd_list_element
*c
)
231 if (target_has_execution ())
233 observer_mode_1
= observer_mode
;
234 error (_("Cannot change this setting while the inferior is running."));
237 observer_mode
= observer_mode_1
;
239 may_write_registers
= !observer_mode
;
240 may_write_memory
= !observer_mode
;
241 may_insert_breakpoints
= !observer_mode
;
242 may_insert_tracepoints
= !observer_mode
;
243 /* We can insert fast tracepoints in or out of observer mode,
244 but enable them if we're going into this mode. */
246 may_insert_fast_tracepoints
= true;
247 may_stop
= !observer_mode
;
248 update_target_permissions ();
250 /* Going *into* observer mode we must force non-stop, then
251 going out we leave it that way. */
254 pagination_enabled
= 0;
255 non_stop
= non_stop_1
= true;
259 printf_filtered (_("Observer mode is now %s.\n"),
260 (observer_mode
? "on" : "off"));
264 show_observer_mode (struct ui_file
*file
, int from_tty
,
265 struct cmd_list_element
*c
, const char *value
)
267 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
270 /* This updates the value of observer mode based on changes in
271 permissions. Note that we are deliberately ignoring the values of
272 may-write-registers and may-write-memory, since the user may have
273 reason to enable these during a session, for instance to turn on a
274 debugging-related global. */
277 update_observer_mode (void)
279 bool newval
= (!may_insert_breakpoints
280 && !may_insert_tracepoints
281 && may_insert_fast_tracepoints
285 /* Let the user know if things change. */
286 if (newval
!= observer_mode
)
287 printf_filtered (_("Observer mode is now %s.\n"),
288 (newval
? "on" : "off"));
290 observer_mode
= observer_mode_1
= newval
;
293 /* Tables of how to react to signals; the user sets them. */
295 static unsigned char signal_stop
[GDB_SIGNAL_LAST
];
296 static unsigned char signal_print
[GDB_SIGNAL_LAST
];
297 static unsigned char signal_program
[GDB_SIGNAL_LAST
];
299 /* Table of signals that are registered with "catch signal". A
300 non-zero entry indicates that the signal is caught by some "catch
302 static unsigned char signal_catch
[GDB_SIGNAL_LAST
];
304 /* Table of signals that the target may silently handle.
305 This is automatically determined from the flags above,
306 and simply cached here. */
307 static unsigned char signal_pass
[GDB_SIGNAL_LAST
];
309 #define SET_SIGS(nsigs,sigs,flags) \
311 int signum = (nsigs); \
312 while (signum-- > 0) \
313 if ((sigs)[signum]) \
314 (flags)[signum] = 1; \
317 #define UNSET_SIGS(nsigs,sigs,flags) \
319 int signum = (nsigs); \
320 while (signum-- > 0) \
321 if ((sigs)[signum]) \
322 (flags)[signum] = 0; \
325 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
326 this function is to avoid exporting `signal_program'. */
329 update_signals_program_target (void)
331 target_program_signals (signal_program
);
334 /* Value to pass to target_resume() to cause all threads to resume. */
336 #define RESUME_ALL minus_one_ptid
338 /* Command list pointer for the "stop" placeholder. */
340 static struct cmd_list_element
*stop_command
;
342 /* Nonzero if we want to give control to the user when we're notified
343 of shared library events by the dynamic linker. */
344 int stop_on_solib_events
;
346 /* Enable or disable optional shared library event breakpoints
347 as appropriate when the above flag is changed. */
350 set_stop_on_solib_events (const char *args
,
351 int from_tty
, struct cmd_list_element
*c
)
353 update_solib_breakpoints ();
357 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
358 struct cmd_list_element
*c
, const char *value
)
360 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
364 /* True after stop if current stack frame should be printed. */
366 static bool stop_print_frame
;
368 /* This is a cached copy of the target/ptid/waitstatus of the last
369 event returned by target_wait()/deprecated_target_wait_hook().
370 This information is returned by get_last_target_status(). */
371 static process_stratum_target
*target_last_proc_target
;
372 static ptid_t target_last_wait_ptid
;
373 static struct target_waitstatus target_last_waitstatus
;
375 void init_thread_stepping_state (struct thread_info
*tss
);
377 static const char follow_fork_mode_child
[] = "child";
378 static const char follow_fork_mode_parent
[] = "parent";
380 static const char *const follow_fork_mode_kind_names
[] = {
381 follow_fork_mode_child
,
382 follow_fork_mode_parent
,
386 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
388 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
389 struct cmd_list_element
*c
, const char *value
)
391 fprintf_filtered (file
,
392 _("Debugger response to a program "
393 "call of fork or vfork is \"%s\".\n"),
398 /* Handle changes to the inferior list based on the type of fork,
399 which process is being followed, and whether the other process
400 should be detached. On entry inferior_ptid must be the ptid of
401 the fork parent. At return inferior_ptid is the ptid of the
402 followed inferior. */
405 follow_fork_inferior (bool follow_child
, bool detach_fork
)
407 target_waitkind fork_kind
= inferior_thread ()->pending_follow
.kind
;
408 gdb_assert (fork_kind
== TARGET_WAITKIND_FORKED
409 || fork_kind
== TARGET_WAITKIND_VFORKED
);
410 bool has_vforked
= fork_kind
== TARGET_WAITKIND_VFORKED
;
411 ptid_t parent_ptid
= inferior_ptid
;
412 ptid_t child_ptid
= inferior_thread ()->pending_follow
.value
.related_pid
;
415 && !non_stop
/* Non-stop always resumes both branches. */
416 && current_ui
->prompt_state
== PROMPT_BLOCKED
417 && !(follow_child
|| detach_fork
|| sched_multi
))
419 /* The parent stays blocked inside the vfork syscall until the
420 child execs or exits. If we don't let the child run, then
421 the parent stays blocked. If we're telling the parent to run
422 in the foreground, the user will not be able to ctrl-c to get
423 back the terminal, effectively hanging the debug session. */
424 fprintf_filtered (gdb_stderr
, _("\
425 Can not resume the parent process over vfork in the foreground while\n\
426 holding the child stopped. Try \"set detach-on-fork\" or \
427 \"set schedule-multiple\".\n"));
431 inferior
*parent_inf
= current_inferior ();
432 inferior
*child_inf
= nullptr;
436 /* Detach new forked process? */
439 /* Before detaching from the child, remove all breakpoints
440 from it. If we forked, then this has already been taken
441 care of by infrun.c. If we vforked however, any
442 breakpoint inserted in the parent is visible in the
443 child, even those added while stopped in a vfork
444 catchpoint. This will remove the breakpoints from the
445 parent also, but they'll be reinserted below. */
448 /* Keep breakpoints list in sync. */
449 remove_breakpoints_inf (current_inferior ());
452 if (print_inferior_events
)
454 /* Ensure that we have a process ptid. */
455 ptid_t process_ptid
= ptid_t (child_ptid
.pid ());
457 target_terminal::ours_for_output ();
458 fprintf_filtered (gdb_stdlog
,
459 _("[Detaching after %s from child %s]\n"),
460 has_vforked
? "vfork" : "fork",
461 target_pid_to_str (process_ptid
).c_str ());
466 /* Add process to GDB's tables. */
467 child_inf
= add_inferior (child_ptid
.pid ());
469 child_inf
->attach_flag
= parent_inf
->attach_flag
;
470 copy_terminal_info (child_inf
, parent_inf
);
471 child_inf
->gdbarch
= parent_inf
->gdbarch
;
472 copy_inferior_target_desc_info (child_inf
, parent_inf
);
474 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
476 /* If this is a vfork child, then the address-space is
477 shared with the parent. */
480 child_inf
->pspace
= parent_inf
->pspace
;
481 child_inf
->aspace
= parent_inf
->aspace
;
483 exec_on_vfork (child_inf
);
485 /* The parent will be frozen until the child is done
486 with the shared region. Keep track of the
488 child_inf
->vfork_parent
= parent_inf
;
489 child_inf
->pending_detach
= 0;
490 parent_inf
->vfork_child
= child_inf
;
491 parent_inf
->pending_detach
= 0;
495 child_inf
->aspace
= new_address_space ();
496 child_inf
->pspace
= new program_space (child_inf
->aspace
);
497 child_inf
->removable
= 1;
498 clone_program_space (child_inf
->pspace
, parent_inf
->pspace
);
504 /* If we detached from the child, then we have to be careful
505 to not insert breakpoints in the parent until the child
506 is done with the shared memory region. However, if we're
507 staying attached to the child, then we can and should
508 insert breakpoints, so that we can debug it. A
509 subsequent child exec or exit is enough to know when does
510 the child stops using the parent's address space. */
511 parent_inf
->waiting_for_vfork_done
= detach_fork
;
512 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
517 /* Follow the child. */
519 if (print_inferior_events
)
521 std::string parent_pid
= target_pid_to_str (parent_ptid
);
522 std::string child_pid
= target_pid_to_str (child_ptid
);
524 target_terminal::ours_for_output ();
525 fprintf_filtered (gdb_stdlog
,
526 _("[Attaching after %s %s to child %s]\n"),
528 has_vforked
? "vfork" : "fork",
532 /* Add the new inferior first, so that the target_detach below
533 doesn't unpush the target. */
535 child_inf
= add_inferior (child_ptid
.pid ());
537 child_inf
->attach_flag
= parent_inf
->attach_flag
;
538 copy_terminal_info (child_inf
, parent_inf
);
539 child_inf
->gdbarch
= parent_inf
->gdbarch
;
540 copy_inferior_target_desc_info (child_inf
, parent_inf
);
542 program_space
*parent_pspace
= parent_inf
->pspace
;
544 /* If this is a vfork child, then the address-space is shared
545 with the parent. If we detached from the parent, then we can
546 reuse the parent's program/address spaces. */
547 if (has_vforked
|| detach_fork
)
549 child_inf
->pspace
= parent_pspace
;
550 child_inf
->aspace
= child_inf
->pspace
->aspace
;
552 exec_on_vfork (child_inf
);
556 child_inf
->aspace
= new_address_space ();
557 child_inf
->pspace
= new program_space (child_inf
->aspace
);
558 child_inf
->removable
= 1;
559 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
560 clone_program_space (child_inf
->pspace
, parent_pspace
);
564 gdb_assert (current_inferior () == parent_inf
);
566 /* If we are setting up an inferior for the child, target_follow_fork is
567 responsible for pushing the appropriate targets on the new inferior's
568 target stack and adding the initial thread (with ptid CHILD_PTID).
570 If we are not setting up an inferior for the child (because following
571 the parent and detach_fork is true), it is responsible for detaching
573 target_follow_fork (child_inf
, child_ptid
, fork_kind
, follow_child
,
576 /* target_follow_fork must leave the parent as the current inferior. If we
577 want to follow the child, we make it the current one below. */
578 gdb_assert (current_inferior () == parent_inf
);
580 /* If there is a child inferior, target_follow_fork must have created a thread
582 if (child_inf
!= nullptr)
583 gdb_assert (!child_inf
->thread_list
.empty ());
585 /* Detach the parent if needed. */
588 /* If we're vforking, we want to hold on to the parent until
589 the child exits or execs. At child exec or exit time we
590 can remove the old breakpoints from the parent and detach
591 or resume debugging it. Otherwise, detach the parent now;
592 we'll want to reuse it's program/address spaces, but we
593 can't set them to the child before removing breakpoints
594 from the parent, otherwise, the breakpoints module could
595 decide to remove breakpoints from the wrong process (since
596 they'd be assigned to the same address space). */
600 gdb_assert (child_inf
->vfork_parent
== NULL
);
601 gdb_assert (parent_inf
->vfork_child
== NULL
);
602 child_inf
->vfork_parent
= parent_inf
;
603 child_inf
->pending_detach
= 0;
604 parent_inf
->vfork_child
= child_inf
;
605 parent_inf
->pending_detach
= detach_fork
;
606 parent_inf
->waiting_for_vfork_done
= 0;
608 else if (detach_fork
)
610 if (print_inferior_events
)
612 /* Ensure that we have a process ptid. */
613 ptid_t process_ptid
= ptid_t (parent_ptid
.pid ());
615 target_terminal::ours_for_output ();
616 fprintf_filtered (gdb_stdlog
,
617 _("[Detaching after fork from "
619 target_pid_to_str (process_ptid
).c_str ());
622 target_detach (parent_inf
, 0);
626 /* If we ended up creating a new inferior, call post_create_inferior to inform
627 the various subcomponents. */
628 if (child_inf
!= nullptr)
630 /* If FOLLOW_CHILD, we leave CHILD_INF as the current inferior
631 (do not restore the parent as the current inferior). */
632 gdb::optional
<scoped_restore_current_thread
> maybe_restore
;
635 maybe_restore
.emplace ();
637 switch_to_thread (*child_inf
->threads ().begin ());
638 post_create_inferior (0);
644 /* Tell the target to follow the fork we're stopped at. Returns true
645 if the inferior should be resumed; false, if the target for some
646 reason decided it's best not to resume. */
651 bool follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
652 bool should_resume
= true;
653 struct thread_info
*tp
;
655 /* Copy user stepping state to the new inferior thread. FIXME: the
656 followed fork child thread should have a copy of most of the
657 parent thread structure's run control related fields, not just these.
658 Initialized to avoid "may be used uninitialized" warnings from gcc. */
659 struct breakpoint
*step_resume_breakpoint
= NULL
;
660 struct breakpoint
*exception_resume_breakpoint
= NULL
;
661 CORE_ADDR step_range_start
= 0;
662 CORE_ADDR step_range_end
= 0;
663 int current_line
= 0;
664 symtab
*current_symtab
= NULL
;
665 struct frame_id step_frame_id
= { 0 };
666 struct thread_fsm
*thread_fsm
= NULL
;
670 process_stratum_target
*wait_target
;
672 struct target_waitstatus wait_status
;
674 /* Get the last target status returned by target_wait(). */
675 get_last_target_status (&wait_target
, &wait_ptid
, &wait_status
);
677 /* If not stopped at a fork event, then there's nothing else to
679 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
680 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
683 /* Check if we switched over from WAIT_PTID, since the event was
685 if (wait_ptid
!= minus_one_ptid
686 && (current_inferior ()->process_target () != wait_target
687 || inferior_ptid
!= wait_ptid
))
689 /* We did. Switch back to WAIT_PTID thread, to tell the
690 target to follow it (in either direction). We'll
691 afterwards refuse to resume, and inform the user what
693 thread_info
*wait_thread
= find_thread_ptid (wait_target
, wait_ptid
);
694 switch_to_thread (wait_thread
);
695 should_resume
= false;
699 tp
= inferior_thread ();
701 /* If there were any forks/vforks that were caught and are now to be
702 followed, then do so now. */
703 switch (tp
->pending_follow
.kind
)
705 case TARGET_WAITKIND_FORKED
:
706 case TARGET_WAITKIND_VFORKED
:
708 ptid_t parent
, child
;
710 /* If the user did a next/step, etc, over a fork call,
711 preserve the stepping state in the fork child. */
712 if (follow_child
&& should_resume
)
714 step_resume_breakpoint
= clone_momentary_breakpoint
715 (tp
->control
.step_resume_breakpoint
);
716 step_range_start
= tp
->control
.step_range_start
;
717 step_range_end
= tp
->control
.step_range_end
;
718 current_line
= tp
->current_line
;
719 current_symtab
= tp
->current_symtab
;
720 step_frame_id
= tp
->control
.step_frame_id
;
721 exception_resume_breakpoint
722 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
723 thread_fsm
= tp
->thread_fsm
;
725 /* For now, delete the parent's sr breakpoint, otherwise,
726 parent/child sr breakpoints are considered duplicates,
727 and the child version will not be installed. Remove
728 this when the breakpoints module becomes aware of
729 inferiors and address spaces. */
730 delete_step_resume_breakpoint (tp
);
731 tp
->control
.step_range_start
= 0;
732 tp
->control
.step_range_end
= 0;
733 tp
->control
.step_frame_id
= null_frame_id
;
734 delete_exception_resume_breakpoint (tp
);
735 tp
->thread_fsm
= NULL
;
738 parent
= inferior_ptid
;
739 child
= tp
->pending_follow
.value
.related_pid
;
741 process_stratum_target
*parent_targ
= tp
->inf
->process_target ();
742 /* Set up inferior(s) as specified by the caller, and tell the
743 target to do whatever is necessary to follow either parent
745 if (follow_fork_inferior (follow_child
, detach_fork
))
747 /* Target refused to follow, or there's some other reason
748 we shouldn't resume. */
753 /* This pending follow fork event is now handled, one way
754 or another. The previous selected thread may be gone
755 from the lists by now, but if it is still around, need
756 to clear the pending follow request. */
757 tp
= find_thread_ptid (parent_targ
, parent
);
759 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
761 /* This makes sure we don't try to apply the "Switched
762 over from WAIT_PID" logic above. */
763 nullify_last_target_wait_ptid ();
765 /* If we followed the child, switch to it... */
768 thread_info
*child_thr
= find_thread_ptid (parent_targ
, child
);
769 switch_to_thread (child_thr
);
771 /* ... and preserve the stepping state, in case the
772 user was stepping over the fork call. */
775 tp
= inferior_thread ();
776 tp
->control
.step_resume_breakpoint
777 = step_resume_breakpoint
;
778 tp
->control
.step_range_start
= step_range_start
;
779 tp
->control
.step_range_end
= step_range_end
;
780 tp
->current_line
= current_line
;
781 tp
->current_symtab
= current_symtab
;
782 tp
->control
.step_frame_id
= step_frame_id
;
783 tp
->control
.exception_resume_breakpoint
784 = exception_resume_breakpoint
;
785 tp
->thread_fsm
= thread_fsm
;
789 /* If we get here, it was because we're trying to
790 resume from a fork catchpoint, but, the user
791 has switched threads away from the thread that
792 forked. In that case, the resume command
793 issued is most likely not applicable to the
794 child, so just warn, and refuse to resume. */
795 warning (_("Not resuming: switched threads "
796 "before following fork child."));
799 /* Reset breakpoints in the child as appropriate. */
800 follow_inferior_reset_breakpoints ();
805 case TARGET_WAITKIND_SPURIOUS
:
806 /* Nothing to follow. */
809 internal_error (__FILE__
, __LINE__
,
810 "Unexpected pending_follow.kind %d\n",
811 tp
->pending_follow
.kind
);
815 return should_resume
;
819 follow_inferior_reset_breakpoints (void)
821 struct thread_info
*tp
= inferior_thread ();
823 /* Was there a step_resume breakpoint? (There was if the user
824 did a "next" at the fork() call.) If so, explicitly reset its
825 thread number. Cloned step_resume breakpoints are disabled on
826 creation, so enable it here now that it is associated with the
829 step_resumes are a form of bp that are made to be per-thread.
830 Since we created the step_resume bp when the parent process
831 was being debugged, and now are switching to the child process,
832 from the breakpoint package's viewpoint, that's a switch of
833 "threads". We must update the bp's notion of which thread
834 it is for, or it'll be ignored when it triggers. */
836 if (tp
->control
.step_resume_breakpoint
)
838 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
839 tp
->control
.step_resume_breakpoint
->loc
->enabled
= 1;
842 /* Treat exception_resume breakpoints like step_resume breakpoints. */
843 if (tp
->control
.exception_resume_breakpoint
)
845 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
846 tp
->control
.exception_resume_breakpoint
->loc
->enabled
= 1;
849 /* Reinsert all breakpoints in the child. The user may have set
850 breakpoints after catching the fork, in which case those
851 were never set in the child, but only in the parent. This makes
852 sure the inserted breakpoints match the breakpoint list. */
854 breakpoint_re_set ();
855 insert_breakpoints ();
858 /* The child has exited or execed: resume THREAD, a thread of the parent,
859 if it was meant to be executing. */
862 proceed_after_vfork_done (thread_info
*thread
)
864 if (thread
->state
== THREAD_RUNNING
865 && !thread
->executing ()
866 && !thread
->stop_requested
867 && thread
->stop_signal () == GDB_SIGNAL_0
)
869 infrun_debug_printf ("resuming vfork parent thread %s",
870 target_pid_to_str (thread
->ptid
).c_str ());
872 switch_to_thread (thread
);
873 clear_proceed_status (0);
874 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
);
878 /* Called whenever we notice an exec or exit event, to handle
879 detaching or resuming a vfork parent. */
882 handle_vfork_child_exec_or_exit (int exec
)
884 struct inferior
*inf
= current_inferior ();
886 if (inf
->vfork_parent
)
888 inferior
*resume_parent
= nullptr;
890 /* This exec or exit marks the end of the shared memory region
891 between the parent and the child. Break the bonds. */
892 inferior
*vfork_parent
= inf
->vfork_parent
;
893 inf
->vfork_parent
->vfork_child
= NULL
;
894 inf
->vfork_parent
= NULL
;
896 /* If the user wanted to detach from the parent, now is the
898 if (vfork_parent
->pending_detach
)
900 struct program_space
*pspace
;
901 struct address_space
*aspace
;
903 /* follow-fork child, detach-on-fork on. */
905 vfork_parent
->pending_detach
= 0;
907 scoped_restore_current_pspace_and_thread restore_thread
;
909 /* We're letting loose of the parent. */
910 thread_info
*tp
= any_live_thread_of_inferior (vfork_parent
);
911 switch_to_thread (tp
);
913 /* We're about to detach from the parent, which implicitly
914 removes breakpoints from its address space. There's a
915 catch here: we want to reuse the spaces for the child,
916 but, parent/child are still sharing the pspace at this
917 point, although the exec in reality makes the kernel give
918 the child a fresh set of new pages. The problem here is
919 that the breakpoints module being unaware of this, would
920 likely chose the child process to write to the parent
921 address space. Swapping the child temporarily away from
922 the spaces has the desired effect. Yes, this is "sort
925 pspace
= inf
->pspace
;
926 aspace
= inf
->aspace
;
930 if (print_inferior_events
)
933 = target_pid_to_str (ptid_t (vfork_parent
->pid
));
935 target_terminal::ours_for_output ();
939 fprintf_filtered (gdb_stdlog
,
940 _("[Detaching vfork parent %s "
941 "after child exec]\n"), pidstr
.c_str ());
945 fprintf_filtered (gdb_stdlog
,
946 _("[Detaching vfork parent %s "
947 "after child exit]\n"), pidstr
.c_str ());
951 target_detach (vfork_parent
, 0);
954 inf
->pspace
= pspace
;
955 inf
->aspace
= aspace
;
959 /* We're staying attached to the parent, so, really give the
960 child a new address space. */
961 inf
->pspace
= new program_space (maybe_new_address_space ());
962 inf
->aspace
= inf
->pspace
->aspace
;
964 set_current_program_space (inf
->pspace
);
966 resume_parent
= vfork_parent
;
970 /* If this is a vfork child exiting, then the pspace and
971 aspaces were shared with the parent. Since we're
972 reporting the process exit, we'll be mourning all that is
973 found in the address space, and switching to null_ptid,
974 preparing to start a new inferior. But, since we don't
975 want to clobber the parent's address/program spaces, we
976 go ahead and create a new one for this exiting
979 /* Switch to no-thread while running clone_program_space, so
980 that clone_program_space doesn't want to read the
981 selected frame of a dead process. */
982 scoped_restore_current_thread restore_thread
;
983 switch_to_no_thread ();
985 inf
->pspace
= new program_space (maybe_new_address_space ());
986 inf
->aspace
= inf
->pspace
->aspace
;
987 set_current_program_space (inf
->pspace
);
989 inf
->symfile_flags
= SYMFILE_NO_READ
;
990 clone_program_space (inf
->pspace
, vfork_parent
->pspace
);
992 resume_parent
= vfork_parent
;
995 gdb_assert (current_program_space
== inf
->pspace
);
997 if (non_stop
&& resume_parent
!= nullptr)
999 /* If the user wanted the parent to be running, let it go
1001 scoped_restore_current_thread restore_thread
;
1003 infrun_debug_printf ("resuming vfork parent process %d",
1004 resume_parent
->pid
);
1006 for (thread_info
*thread
: resume_parent
->threads ())
1007 proceed_after_vfork_done (thread
);
1012 /* Enum strings for "set|show follow-exec-mode". */
1014 static const char follow_exec_mode_new
[] = "new";
1015 static const char follow_exec_mode_same
[] = "same";
1016 static const char *const follow_exec_mode_names
[] =
1018 follow_exec_mode_new
,
1019 follow_exec_mode_same
,
1023 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1025 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1026 struct cmd_list_element
*c
, const char *value
)
1028 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1031 /* EXEC_FILE_TARGET is assumed to be non-NULL. */
1034 follow_exec (ptid_t ptid
, const char *exec_file_target
)
1036 int pid
= ptid
.pid ();
1037 ptid_t process_ptid
;
1039 /* Switch terminal for any messages produced e.g. by
1040 breakpoint_re_set. */
1041 target_terminal::ours_for_output ();
1043 /* This is an exec event that we actually wish to pay attention to.
1044 Refresh our symbol table to the newly exec'd program, remove any
1045 momentary bp's, etc.
1047 If there are breakpoints, they aren't really inserted now,
1048 since the exec() transformed our inferior into a fresh set
1051 We want to preserve symbolic breakpoints on the list, since
1052 we have hopes that they can be reset after the new a.out's
1053 symbol table is read.
1055 However, any "raw" breakpoints must be removed from the list
1056 (e.g., the solib bp's), since their address is probably invalid
1059 And, we DON'T want to call delete_breakpoints() here, since
1060 that may write the bp's "shadow contents" (the instruction
1061 value that was overwritten with a TRAP instruction). Since
1062 we now have a new a.out, those shadow contents aren't valid. */
1064 mark_breakpoints_out ();
1066 /* The target reports the exec event to the main thread, even if
1067 some other thread does the exec, and even if the main thread was
1068 stopped or already gone. We may still have non-leader threads of
1069 the process on our list. E.g., on targets that don't have thread
1070 exit events (like remote); or on native Linux in non-stop mode if
1071 there were only two threads in the inferior and the non-leader
1072 one is the one that execs (and nothing forces an update of the
1073 thread list up to here). When debugging remotely, it's best to
1074 avoid extra traffic, when possible, so avoid syncing the thread
1075 list with the target, and instead go ahead and delete all threads
1076 of the process but one that reported the event. Note this must
1077 be done before calling update_breakpoints_after_exec, as
1078 otherwise clearing the threads' resources would reference stale
1079 thread breakpoints -- it may have been one of these threads that
1080 stepped across the exec. We could just clear their stepping
1081 states, but as long as we're iterating, might as well delete
1082 them. Deleting them now rather than at the next user-visible
1083 stop provides a nicer sequence of events for user and MI
1085 for (thread_info
*th
: all_threads_safe ())
1086 if (th
->ptid
.pid () == pid
&& th
->ptid
!= ptid
)
1089 /* We also need to clear any left over stale state for the
1090 leader/event thread. E.g., if there was any step-resume
1091 breakpoint or similar, it's gone now. We cannot truly
1092 step-to-next statement through an exec(). */
1093 thread_info
*th
= inferior_thread ();
1094 th
->control
.step_resume_breakpoint
= NULL
;
1095 th
->control
.exception_resume_breakpoint
= NULL
;
1096 th
->control
.single_step_breakpoints
= NULL
;
1097 th
->control
.step_range_start
= 0;
1098 th
->control
.step_range_end
= 0;
1100 /* The user may have had the main thread held stopped in the
1101 previous image (e.g., schedlock on, or non-stop). Release
1103 th
->stop_requested
= 0;
1105 update_breakpoints_after_exec ();
1107 /* What is this a.out's name? */
1108 process_ptid
= ptid_t (pid
);
1109 printf_unfiltered (_("%s is executing new program: %s\n"),
1110 target_pid_to_str (process_ptid
).c_str (),
1113 /* We've followed the inferior through an exec. Therefore, the
1114 inferior has essentially been killed & reborn. */
1116 breakpoint_init_inferior (inf_execd
);
1118 gdb::unique_xmalloc_ptr
<char> exec_file_host
1119 = exec_file_find (exec_file_target
, NULL
);
1121 /* If we were unable to map the executable target pathname onto a host
1122 pathname, tell the user that. Otherwise GDB's subsequent behavior
1123 is confusing. Maybe it would even be better to stop at this point
1124 so that the user can specify a file manually before continuing. */
1125 if (exec_file_host
== NULL
)
1126 warning (_("Could not load symbols for executable %s.\n"
1127 "Do you need \"set sysroot\"?"),
1130 /* Reset the shared library package. This ensures that we get a
1131 shlib event when the child reaches "_start", at which point the
1132 dld will have had a chance to initialize the child. */
1133 /* Also, loading a symbol file below may trigger symbol lookups, and
1134 we don't want those to be satisfied by the libraries of the
1135 previous incarnation of this process. */
1136 no_shared_libraries (NULL
, 0);
1138 struct inferior
*inf
= current_inferior ();
1140 if (follow_exec_mode_string
== follow_exec_mode_new
)
1142 /* The user wants to keep the old inferior and program spaces
1143 around. Create a new fresh one, and switch to it. */
1145 /* Do exit processing for the original inferior before setting the new
1146 inferior's pid. Having two inferiors with the same pid would confuse
1147 find_inferior_p(t)id. Transfer the terminal state and info from the
1148 old to the new inferior. */
1149 inferior
*new_inferior
= add_inferior_with_spaces ();
1151 swap_terminal_info (new_inferior
, inf
);
1152 exit_inferior_silent (inf
);
1154 new_inferior
->pid
= pid
;
1155 target_follow_exec (new_inferior
, ptid
, exec_file_target
);
1157 /* We continue with the new inferior. */
1162 /* The old description may no longer be fit for the new image.
1163 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1164 old description; we'll read a new one below. No need to do
1165 this on "follow-exec-mode new", as the old inferior stays
1166 around (its description is later cleared/refetched on
1168 target_clear_description ();
1169 target_follow_exec (inf
, ptid
, exec_file_target
);
1172 gdb_assert (current_inferior () == inf
);
1173 gdb_assert (current_program_space
== inf
->pspace
);
1175 /* Attempt to open the exec file. SYMFILE_DEFER_BP_RESET is used
1176 because the proper displacement for a PIE (Position Independent
1177 Executable) main symbol file will only be computed by
1178 solib_create_inferior_hook below. breakpoint_re_set would fail
1179 to insert the breakpoints with the zero displacement. */
1180 try_open_exec_file (exec_file_host
.get (), inf
, SYMFILE_DEFER_BP_RESET
);
1182 /* If the target can specify a description, read it. Must do this
1183 after flipping to the new executable (because the target supplied
1184 description must be compatible with the executable's
1185 architecture, and the old executable may e.g., be 32-bit, while
1186 the new one 64-bit), and before anything involving memory or
1188 target_find_description ();
1190 gdb::observers::inferior_execd
.notify (inf
);
1192 breakpoint_re_set ();
1194 /* Reinsert all breakpoints. (Those which were symbolic have
1195 been reset to the proper address in the new a.out, thanks
1196 to symbol_file_command...). */
1197 insert_breakpoints ();
1199 /* The next resume of this inferior should bring it to the shlib
1200 startup breakpoints. (If the user had also set bp's on
1201 "main" from the old (parent) process, then they'll auto-
1202 matically get reset there in the new process.). */
1205 /* The chain of threads that need to do a step-over operation to get
1206 past e.g., a breakpoint. What technique is used to step over the
1207 breakpoint/watchpoint does not matter -- all threads end up in the
1208 same queue, to maintain rough temporal order of execution, in order
1209 to avoid starvation, otherwise, we could e.g., find ourselves
1210 constantly stepping the same couple threads past their breakpoints
1211 over and over, if the single-step finish fast enough. */
1212 thread_step_over_list global_thread_step_over_list
;
1214 /* Bit flags indicating what the thread needs to step over. */
1216 enum step_over_what_flag
1218 /* Step over a breakpoint. */
1219 STEP_OVER_BREAKPOINT
= 1,
1221 /* Step past a non-continuable watchpoint, in order to let the
1222 instruction execute so we can evaluate the watchpoint
1224 STEP_OVER_WATCHPOINT
= 2
1226 DEF_ENUM_FLAGS_TYPE (enum step_over_what_flag
, step_over_what
);
1228 /* Info about an instruction that is being stepped over. */
1230 struct step_over_info
1232 /* If we're stepping past a breakpoint, this is the address space
1233 and address of the instruction the breakpoint is set at. We'll
1234 skip inserting all breakpoints here. Valid iff ASPACE is
1236 const address_space
*aspace
= nullptr;
1237 CORE_ADDR address
= 0;
1239 /* The instruction being stepped over triggers a nonsteppable
1240 watchpoint. If true, we'll skip inserting watchpoints. */
1241 int nonsteppable_watchpoint_p
= 0;
1243 /* The thread's global number. */
1247 /* The step-over info of the location that is being stepped over.
1249 Note that with async/breakpoint always-inserted mode, a user might
1250 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1251 being stepped over. As setting a new breakpoint inserts all
1252 breakpoints, we need to make sure the breakpoint being stepped over
1253 isn't inserted then. We do that by only clearing the step-over
1254 info when the step-over is actually finished (or aborted).
1256 Presently GDB can only step over one breakpoint at any given time.
1257 Given threads that can't run code in the same address space as the
1258 breakpoint's can't really miss the breakpoint, GDB could be taught
1259 to step-over at most one breakpoint per address space (so this info
1260 could move to the address space object if/when GDB is extended).
1261 The set of breakpoints being stepped over will normally be much
1262 smaller than the set of all breakpoints, so a flag in the
1263 breakpoint location structure would be wasteful. A separate list
1264 also saves complexity and run-time, as otherwise we'd have to go
1265 through all breakpoint locations clearing their flag whenever we
1266 start a new sequence. Similar considerations weigh against storing
1267 this info in the thread object. Plus, not all step overs actually
1268 have breakpoint locations -- e.g., stepping past a single-step
1269 breakpoint, or stepping to complete a non-continuable
1271 static struct step_over_info step_over_info
;
1273 /* Record the address of the breakpoint/instruction we're currently
1275 N.B. We record the aspace and address now, instead of say just the thread,
1276 because when we need the info later the thread may be running. */
1279 set_step_over_info (const address_space
*aspace
, CORE_ADDR address
,
1280 int nonsteppable_watchpoint_p
,
1283 step_over_info
.aspace
= aspace
;
1284 step_over_info
.address
= address
;
1285 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1286 step_over_info
.thread
= thread
;
1289 /* Called when we're not longer stepping over a breakpoint / an
1290 instruction, so all breakpoints are free to be (re)inserted. */
1293 clear_step_over_info (void)
1295 infrun_debug_printf ("clearing step over info");
1296 step_over_info
.aspace
= NULL
;
1297 step_over_info
.address
= 0;
1298 step_over_info
.nonsteppable_watchpoint_p
= 0;
1299 step_over_info
.thread
= -1;
1305 stepping_past_instruction_at (struct address_space
*aspace
,
1308 return (step_over_info
.aspace
!= NULL
1309 && breakpoint_address_match (aspace
, address
,
1310 step_over_info
.aspace
,
1311 step_over_info
.address
));
1317 thread_is_stepping_over_breakpoint (int thread
)
1319 return (step_over_info
.thread
!= -1
1320 && thread
== step_over_info
.thread
);
1326 stepping_past_nonsteppable_watchpoint (void)
1328 return step_over_info
.nonsteppable_watchpoint_p
;
1331 /* Returns true if step-over info is valid. */
1334 step_over_info_valid_p (void)
1336 return (step_over_info
.aspace
!= NULL
1337 || stepping_past_nonsteppable_watchpoint ());
1341 /* Displaced stepping. */
1343 /* In non-stop debugging mode, we must take special care to manage
1344 breakpoints properly; in particular, the traditional strategy for
1345 stepping a thread past a breakpoint it has hit is unsuitable.
1346 'Displaced stepping' is a tactic for stepping one thread past a
1347 breakpoint it has hit while ensuring that other threads running
1348 concurrently will hit the breakpoint as they should.
1350 The traditional way to step a thread T off a breakpoint in a
1351 multi-threaded program in all-stop mode is as follows:
1353 a0) Initially, all threads are stopped, and breakpoints are not
1355 a1) We single-step T, leaving breakpoints uninserted.
1356 a2) We insert breakpoints, and resume all threads.
1358 In non-stop debugging, however, this strategy is unsuitable: we
1359 don't want to have to stop all threads in the system in order to
1360 continue or step T past a breakpoint. Instead, we use displaced
1363 n0) Initially, T is stopped, other threads are running, and
1364 breakpoints are inserted.
1365 n1) We copy the instruction "under" the breakpoint to a separate
1366 location, outside the main code stream, making any adjustments
1367 to the instruction, register, and memory state as directed by
1369 n2) We single-step T over the instruction at its new location.
1370 n3) We adjust the resulting register and memory state as directed
1371 by T's architecture. This includes resetting T's PC to point
1372 back into the main instruction stream.
1375 This approach depends on the following gdbarch methods:
1377 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1378 indicate where to copy the instruction, and how much space must
1379 be reserved there. We use these in step n1.
1381 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1382 address, and makes any necessary adjustments to the instruction,
1383 register contents, and memory. We use this in step n1.
1385 - gdbarch_displaced_step_fixup adjusts registers and memory after
1386 we have successfully single-stepped the instruction, to yield the
1387 same effect the instruction would have had if we had executed it
1388 at its original address. We use this in step n3.
1390 The gdbarch_displaced_step_copy_insn and
1391 gdbarch_displaced_step_fixup functions must be written so that
1392 copying an instruction with gdbarch_displaced_step_copy_insn,
1393 single-stepping across the copied instruction, and then applying
1394 gdbarch_displaced_insn_fixup should have the same effects on the
1395 thread's memory and registers as stepping the instruction in place
1396 would have. Exactly which responsibilities fall to the copy and
1397 which fall to the fixup is up to the author of those functions.
1399 See the comments in gdbarch.sh for details.
1401 Note that displaced stepping and software single-step cannot
1402 currently be used in combination, although with some care I think
1403 they could be made to. Software single-step works by placing
1404 breakpoints on all possible subsequent instructions; if the
1405 displaced instruction is a PC-relative jump, those breakpoints
1406 could fall in very strange places --- on pages that aren't
1407 executable, or at addresses that are not proper instruction
1408 boundaries. (We do generally let other threads run while we wait
1409 to hit the software single-step breakpoint, and they might
1410 encounter such a corrupted instruction.) One way to work around
1411 this would be to have gdbarch_displaced_step_copy_insn fully
1412 simulate the effect of PC-relative instructions (and return NULL)
1413 on architectures that use software single-stepping.
1415 In non-stop mode, we can have independent and simultaneous step
1416 requests, so more than one thread may need to simultaneously step
1417 over a breakpoint. The current implementation assumes there is
1418 only one scratch space per process. In this case, we have to
1419 serialize access to the scratch space. If thread A wants to step
1420 over a breakpoint, but we are currently waiting for some other
1421 thread to complete a displaced step, we leave thread A stopped and
1422 place it in the displaced_step_request_queue. Whenever a displaced
1423 step finishes, we pick the next thread in the queue and start a new
1424 displaced step operation on it. See displaced_step_prepare and
1425 displaced_step_finish for details. */
1427 /* Return true if THREAD is doing a displaced step. */
1430 displaced_step_in_progress_thread (thread_info
*thread
)
1432 gdb_assert (thread
!= NULL
);
1434 return thread
->displaced_step_state
.in_progress ();
1437 /* Return true if INF has a thread doing a displaced step. */
1440 displaced_step_in_progress (inferior
*inf
)
1442 return inf
->displaced_step_state
.in_progress_count
> 0;
1445 /* Return true if any thread is doing a displaced step. */
1448 displaced_step_in_progress_any_thread ()
1450 for (inferior
*inf
: all_non_exited_inferiors ())
1452 if (displaced_step_in_progress (inf
))
1460 infrun_inferior_exit (struct inferior
*inf
)
1462 inf
->displaced_step_state
.reset ();
1466 infrun_inferior_execd (inferior
*inf
)
1468 /* If some threads where was doing a displaced step in this inferior at the
1469 moment of the exec, they no longer exist. Even if the exec'ing thread
1470 doing a displaced step, we don't want to to any fixup nor restore displaced
1471 stepping buffer bytes. */
1472 inf
->displaced_step_state
.reset ();
1474 for (thread_info
*thread
: inf
->threads ())
1475 thread
->displaced_step_state
.reset ();
1477 /* Since an in-line step is done with everything else stopped, if there was
1478 one in progress at the time of the exec, it must have been the exec'ing
1480 clear_step_over_info ();
1483 /* If ON, and the architecture supports it, GDB will use displaced
1484 stepping to step over breakpoints. If OFF, or if the architecture
1485 doesn't support it, GDB will instead use the traditional
1486 hold-and-step approach. If AUTO (which is the default), GDB will
1487 decide which technique to use to step over breakpoints depending on
1488 whether the target works in a non-stop way (see use_displaced_stepping). */
1490 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1493 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1494 struct cmd_list_element
*c
,
1497 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1498 fprintf_filtered (file
,
1499 _("Debugger's willingness to use displaced stepping "
1500 "to step over breakpoints is %s (currently %s).\n"),
1501 value
, target_is_non_stop_p () ? "on" : "off");
1503 fprintf_filtered (file
,
1504 _("Debugger's willingness to use displaced stepping "
1505 "to step over breakpoints is %s.\n"), value
);
1508 /* Return true if the gdbarch implements the required methods to use
1509 displaced stepping. */
1512 gdbarch_supports_displaced_stepping (gdbarch
*arch
)
1514 /* Only check for the presence of `prepare`. The gdbarch verification ensures
1515 that if `prepare` is provided, so is `finish`. */
1516 return gdbarch_displaced_step_prepare_p (arch
);
1519 /* Return non-zero if displaced stepping can/should be used to step
1520 over breakpoints of thread TP. */
1523 use_displaced_stepping (thread_info
*tp
)
1525 /* If the user disabled it explicitly, don't use displaced stepping. */
1526 if (can_use_displaced_stepping
== AUTO_BOOLEAN_FALSE
)
1529 /* If "auto", only use displaced stepping if the target operates in a non-stop
1531 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
1532 && !target_is_non_stop_p ())
1535 gdbarch
*gdbarch
= get_thread_regcache (tp
)->arch ();
1537 /* If the architecture doesn't implement displaced stepping, don't use
1539 if (!gdbarch_supports_displaced_stepping (gdbarch
))
1542 /* If recording, don't use displaced stepping. */
1543 if (find_record_target () != nullptr)
1546 /* If displaced stepping failed before for this inferior, don't bother trying
1548 if (tp
->inf
->displaced_step_state
.failed_before
)
1554 /* Simple function wrapper around displaced_step_thread_state::reset. */
1557 displaced_step_reset (displaced_step_thread_state
*displaced
)
1559 displaced
->reset ();
1562 /* A cleanup that wraps displaced_step_reset. We use this instead of, say,
1563 SCOPE_EXIT, because it needs to be discardable with "cleanup.release ()". */
1565 using displaced_step_reset_cleanup
= FORWARD_SCOPE_EXIT (displaced_step_reset
);
1570 displaced_step_dump_bytes (const gdb_byte
*buf
, size_t len
)
1574 for (size_t i
= 0; i
< len
; i
++)
1577 ret
+= string_printf ("%02x", buf
[i
]);
1579 ret
+= string_printf (" %02x", buf
[i
]);
1585 /* Prepare to single-step, using displaced stepping.
1587 Note that we cannot use displaced stepping when we have a signal to
1588 deliver. If we have a signal to deliver and an instruction to step
1589 over, then after the step, there will be no indication from the
1590 target whether the thread entered a signal handler or ignored the
1591 signal and stepped over the instruction successfully --- both cases
1592 result in a simple SIGTRAP. In the first case we mustn't do a
1593 fixup, and in the second case we must --- but we can't tell which.
1594 Comments in the code for 'random signals' in handle_inferior_event
1595 explain how we handle this case instead.
1597 Returns DISPLACED_STEP_PREPARE_STATUS_OK if preparing was successful -- this
1598 thread is going to be stepped now; DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE
1599 if displaced stepping this thread got queued; or
1600 DISPLACED_STEP_PREPARE_STATUS_CANT if this instruction can't be displaced
1603 static displaced_step_prepare_status
1604 displaced_step_prepare_throw (thread_info
*tp
)
1606 regcache
*regcache
= get_thread_regcache (tp
);
1607 struct gdbarch
*gdbarch
= regcache
->arch ();
1608 displaced_step_thread_state
&disp_step_thread_state
1609 = tp
->displaced_step_state
;
1611 /* We should never reach this function if the architecture does not
1612 support displaced stepping. */
1613 gdb_assert (gdbarch_supports_displaced_stepping (gdbarch
));
1615 /* Nor if the thread isn't meant to step over a breakpoint. */
1616 gdb_assert (tp
->control
.trap_expected
);
1618 /* Disable range stepping while executing in the scratch pad. We
1619 want a single-step even if executing the displaced instruction in
1620 the scratch buffer lands within the stepping range (e.g., a
1622 tp
->control
.may_range_step
= 0;
1624 /* We are about to start a displaced step for this thread. If one is already
1625 in progress, something's wrong. */
1626 gdb_assert (!disp_step_thread_state
.in_progress ());
1628 if (tp
->inf
->displaced_step_state
.unavailable
)
1630 /* The gdbarch tells us it's not worth asking to try a prepare because
1631 it is likely that it will return unavailable, so don't bother asking. */
1633 displaced_debug_printf ("deferring step of %s",
1634 target_pid_to_str (tp
->ptid
).c_str ());
1636 global_thread_step_over_chain_enqueue (tp
);
1637 return DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE
;
1640 displaced_debug_printf ("displaced-stepping %s now",
1641 target_pid_to_str (tp
->ptid
).c_str ());
1643 scoped_restore_current_thread restore_thread
;
1645 switch_to_thread (tp
);
1647 CORE_ADDR original_pc
= regcache_read_pc (regcache
);
1648 CORE_ADDR displaced_pc
;
1650 displaced_step_prepare_status status
1651 = gdbarch_displaced_step_prepare (gdbarch
, tp
, displaced_pc
);
1653 if (status
== DISPLACED_STEP_PREPARE_STATUS_CANT
)
1655 displaced_debug_printf ("failed to prepare (%s)",
1656 target_pid_to_str (tp
->ptid
).c_str ());
1658 return DISPLACED_STEP_PREPARE_STATUS_CANT
;
1660 else if (status
== DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE
)
1662 /* Not enough displaced stepping resources available, defer this
1663 request by placing it the queue. */
1665 displaced_debug_printf ("not enough resources available, "
1666 "deferring step of %s",
1667 target_pid_to_str (tp
->ptid
).c_str ());
1669 global_thread_step_over_chain_enqueue (tp
);
1671 return DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE
;
1674 gdb_assert (status
== DISPLACED_STEP_PREPARE_STATUS_OK
);
1676 /* Save the information we need to fix things up if the step
1678 disp_step_thread_state
.set (gdbarch
);
1680 tp
->inf
->displaced_step_state
.in_progress_count
++;
1682 displaced_debug_printf ("prepared successfully thread=%s, "
1683 "original_pc=%s, displaced_pc=%s",
1684 target_pid_to_str (tp
->ptid
).c_str (),
1685 paddress (gdbarch
, original_pc
),
1686 paddress (gdbarch
, displaced_pc
));
1688 return DISPLACED_STEP_PREPARE_STATUS_OK
;
1691 /* Wrapper for displaced_step_prepare_throw that disabled further
1692 attempts at displaced stepping if we get a memory error. */
1694 static displaced_step_prepare_status
1695 displaced_step_prepare (thread_info
*thread
)
1697 displaced_step_prepare_status status
1698 = DISPLACED_STEP_PREPARE_STATUS_CANT
;
1702 status
= displaced_step_prepare_throw (thread
);
1704 catch (const gdb_exception_error
&ex
)
1706 if (ex
.error
!= MEMORY_ERROR
1707 && ex
.error
!= NOT_SUPPORTED_ERROR
)
1710 infrun_debug_printf ("caught exception, disabling displaced stepping: %s",
1713 /* Be verbose if "set displaced-stepping" is "on", silent if
1715 if (can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1717 warning (_("disabling displaced stepping: %s"),
1721 /* Disable further displaced stepping attempts. */
1722 thread
->inf
->displaced_step_state
.failed_before
= 1;
1728 /* If we displaced stepped an instruction successfully, adjust registers and
1729 memory to yield the same effect the instruction would have had if we had
1730 executed it at its original address, and return
1731 DISPLACED_STEP_FINISH_STATUS_OK. If the instruction didn't complete,
1732 relocate the PC and return DISPLACED_STEP_FINISH_STATUS_NOT_EXECUTED.
1734 If the thread wasn't displaced stepping, return
1735 DISPLACED_STEP_FINISH_STATUS_OK as well. */
1737 static displaced_step_finish_status
1738 displaced_step_finish (thread_info
*event_thread
, enum gdb_signal signal
)
1740 displaced_step_thread_state
*displaced
= &event_thread
->displaced_step_state
;
1742 /* Was this thread performing a displaced step? */
1743 if (!displaced
->in_progress ())
1744 return DISPLACED_STEP_FINISH_STATUS_OK
;
1746 gdb_assert (event_thread
->inf
->displaced_step_state
.in_progress_count
> 0);
1747 event_thread
->inf
->displaced_step_state
.in_progress_count
--;
1749 /* Fixup may need to read memory/registers. Switch to the thread
1750 that we're fixing up. Also, target_stopped_by_watchpoint checks
1751 the current thread, and displaced_step_restore performs ptid-dependent
1752 memory accesses using current_inferior(). */
1753 switch_to_thread (event_thread
);
1755 displaced_step_reset_cleanup
cleanup (displaced
);
1757 /* Do the fixup, and release the resources acquired to do the displaced
1759 return gdbarch_displaced_step_finish (displaced
->get_original_gdbarch (),
1760 event_thread
, signal
);
1763 /* Data to be passed around while handling an event. This data is
1764 discarded between events. */
1765 struct execution_control_state
1767 process_stratum_target
*target
;
1769 /* The thread that got the event, if this was a thread event; NULL
1771 struct thread_info
*event_thread
;
1773 struct target_waitstatus ws
;
1774 int stop_func_filled_in
;
1775 CORE_ADDR stop_func_start
;
1776 CORE_ADDR stop_func_end
;
1777 const char *stop_func_name
;
1780 /* True if the event thread hit the single-step breakpoint of
1781 another thread. Thus the event doesn't cause a stop, the thread
1782 needs to be single-stepped past the single-step breakpoint before
1783 we can switch back to the original stepping thread. */
1784 int hit_singlestep_breakpoint
;
1787 /* Clear ECS and set it to point at TP. */
1790 reset_ecs (struct execution_control_state
*ecs
, struct thread_info
*tp
)
1792 memset (ecs
, 0, sizeof (*ecs
));
1793 ecs
->event_thread
= tp
;
1794 ecs
->ptid
= tp
->ptid
;
1797 static void keep_going_pass_signal (struct execution_control_state
*ecs
);
1798 static void prepare_to_wait (struct execution_control_state
*ecs
);
1799 static bool keep_going_stepped_thread (struct thread_info
*tp
);
1800 static step_over_what
thread_still_needs_step_over (struct thread_info
*tp
);
1802 /* Are there any pending step-over requests? If so, run all we can
1803 now and return true. Otherwise, return false. */
1806 start_step_over (void)
1808 INFRUN_SCOPED_DEBUG_ENTER_EXIT
;
1810 /* Don't start a new step-over if we already have an in-line
1811 step-over operation ongoing. */
1812 if (step_over_info_valid_p ())
1815 /* Steal the global thread step over chain. As we try to initiate displaced
1816 steps, threads will be enqueued in the global chain if no buffers are
1817 available. If we iterated on the global chain directly, we might iterate
1819 thread_step_over_list threads_to_step
1820 = std::move (global_thread_step_over_list
);
1822 infrun_debug_printf ("stealing global queue of threads to step, length = %d",
1823 thread_step_over_chain_length (threads_to_step
));
1825 bool started
= false;
1827 /* On scope exit (whatever the reason, return or exception), if there are
1828 threads left in the THREADS_TO_STEP chain, put back these threads in the
1832 if (threads_to_step
.empty ())
1833 infrun_debug_printf ("step-over queue now empty");
1836 infrun_debug_printf ("putting back %d threads to step in global queue",
1837 thread_step_over_chain_length (threads_to_step
));
1839 global_thread_step_over_chain_enqueue_chain
1840 (std::move (threads_to_step
));
1844 thread_step_over_list_safe_range range
1845 = make_thread_step_over_list_safe_range (threads_to_step
);
1847 for (thread_info
*tp
: range
)
1849 struct execution_control_state ecss
;
1850 struct execution_control_state
*ecs
= &ecss
;
1851 step_over_what step_what
;
1852 int must_be_in_line
;
1854 gdb_assert (!tp
->stop_requested
);
1856 if (tp
->inf
->displaced_step_state
.unavailable
)
1858 /* The arch told us to not even try preparing another displaced step
1859 for this inferior. Just leave the thread in THREADS_TO_STEP, it
1860 will get moved to the global chain on scope exit. */
1864 /* Remove thread from the THREADS_TO_STEP chain. If anything goes wrong
1865 while we try to prepare the displaced step, we don't add it back to
1866 the global step over chain. This is to avoid a thread staying in the
1867 step over chain indefinitely if something goes wrong when resuming it
1868 If the error is intermittent and it still needs a step over, it will
1869 get enqueued again when we try to resume it normally. */
1870 threads_to_step
.erase (threads_to_step
.iterator_to (*tp
));
1872 step_what
= thread_still_needs_step_over (tp
);
1873 must_be_in_line
= ((step_what
& STEP_OVER_WATCHPOINT
)
1874 || ((step_what
& STEP_OVER_BREAKPOINT
)
1875 && !use_displaced_stepping (tp
)));
1877 /* We currently stop all threads of all processes to step-over
1878 in-line. If we need to start a new in-line step-over, let
1879 any pending displaced steps finish first. */
1880 if (must_be_in_line
&& displaced_step_in_progress_any_thread ())
1882 global_thread_step_over_chain_enqueue (tp
);
1886 if (tp
->control
.trap_expected
1888 || tp
->executing ())
1890 internal_error (__FILE__
, __LINE__
,
1891 "[%s] has inconsistent state: "
1892 "trap_expected=%d, resumed=%d, executing=%d\n",
1893 target_pid_to_str (tp
->ptid
).c_str (),
1894 tp
->control
.trap_expected
,
1899 infrun_debug_printf ("resuming [%s] for step-over",
1900 target_pid_to_str (tp
->ptid
).c_str ());
1902 /* keep_going_pass_signal skips the step-over if the breakpoint
1903 is no longer inserted. In all-stop, we want to keep looking
1904 for a thread that needs a step-over instead of resuming TP,
1905 because we wouldn't be able to resume anything else until the
1906 target stops again. In non-stop, the resume always resumes
1907 only TP, so it's OK to let the thread resume freely. */
1908 if (!target_is_non_stop_p () && !step_what
)
1911 switch_to_thread (tp
);
1912 reset_ecs (ecs
, tp
);
1913 keep_going_pass_signal (ecs
);
1915 if (!ecs
->wait_some_more
)
1916 error (_("Command aborted."));
1918 /* If the thread's step over could not be initiated because no buffers
1919 were available, it was re-added to the global step over chain. */
1922 infrun_debug_printf ("[%s] was resumed.",
1923 target_pid_to_str (tp
->ptid
).c_str ());
1924 gdb_assert (!thread_is_in_step_over_chain (tp
));
1928 infrun_debug_printf ("[%s] was NOT resumed.",
1929 target_pid_to_str (tp
->ptid
).c_str ());
1930 gdb_assert (thread_is_in_step_over_chain (tp
));
1933 /* If we started a new in-line step-over, we're done. */
1934 if (step_over_info_valid_p ())
1936 gdb_assert (tp
->control
.trap_expected
);
1941 if (!target_is_non_stop_p ())
1943 /* On all-stop, shouldn't have resumed unless we needed a
1945 gdb_assert (tp
->control
.trap_expected
1946 || tp
->step_after_step_resume_breakpoint
);
1948 /* With remote targets (at least), in all-stop, we can't
1949 issue any further remote commands until the program stops
1955 /* Either the thread no longer needed a step-over, or a new
1956 displaced stepping sequence started. Even in the latter
1957 case, continue looking. Maybe we can also start another
1958 displaced step on a thread of other process. */
1964 /* Update global variables holding ptids to hold NEW_PTID if they were
1965 holding OLD_PTID. */
1967 infrun_thread_ptid_changed (process_stratum_target
*target
,
1968 ptid_t old_ptid
, ptid_t new_ptid
)
1970 if (inferior_ptid
== old_ptid
1971 && current_inferior ()->process_target () == target
)
1972 inferior_ptid
= new_ptid
;
1977 static const char schedlock_off
[] = "off";
1978 static const char schedlock_on
[] = "on";
1979 static const char schedlock_step
[] = "step";
1980 static const char schedlock_replay
[] = "replay";
1981 static const char *const scheduler_enums
[] = {
1988 static const char *scheduler_mode
= schedlock_replay
;
1990 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
1991 struct cmd_list_element
*c
, const char *value
)
1993 fprintf_filtered (file
,
1994 _("Mode for locking scheduler "
1995 "during execution is \"%s\".\n"),
2000 set_schedlock_func (const char *args
, int from_tty
, struct cmd_list_element
*c
)
2002 if (!target_can_lock_scheduler ())
2004 scheduler_mode
= schedlock_off
;
2005 error (_("Target '%s' cannot support this command."),
2006 target_shortname ());
2010 /* True if execution commands resume all threads of all processes by
2011 default; otherwise, resume only threads of the current inferior
2013 bool sched_multi
= false;
2015 /* Try to setup for software single stepping. Return true if target_resume()
2016 should use hardware single step.
2018 GDBARCH the current gdbarch. */
2021 maybe_software_singlestep (struct gdbarch
*gdbarch
)
2023 bool hw_step
= true;
2025 if (execution_direction
== EXEC_FORWARD
2026 && gdbarch_software_single_step_p (gdbarch
))
2027 hw_step
= !insert_single_step_breakpoints (gdbarch
);
2035 user_visible_resume_ptid (int step
)
2041 /* With non-stop mode on, threads are always handled
2043 resume_ptid
= inferior_ptid
;
2045 else if ((scheduler_mode
== schedlock_on
)
2046 || (scheduler_mode
== schedlock_step
&& step
))
2048 /* User-settable 'scheduler' mode requires solo thread
2050 resume_ptid
= inferior_ptid
;
2052 else if ((scheduler_mode
== schedlock_replay
)
2053 && target_record_will_replay (minus_one_ptid
, execution_direction
))
2055 /* User-settable 'scheduler' mode requires solo thread resume in replay
2057 resume_ptid
= inferior_ptid
;
2059 else if (!sched_multi
&& target_supports_multi_process ())
2061 /* Resume all threads of the current process (and none of other
2063 resume_ptid
= ptid_t (inferior_ptid
.pid ());
2067 /* Resume all threads of all processes. */
2068 resume_ptid
= RESUME_ALL
;
2076 process_stratum_target
*
2077 user_visible_resume_target (ptid_t resume_ptid
)
2079 return (resume_ptid
== minus_one_ptid
&& sched_multi
2081 : current_inferior ()->process_target ());
2084 /* Return a ptid representing the set of threads that we will resume,
2085 in the perspective of the target, assuming run control handling
2086 does not require leaving some threads stopped (e.g., stepping past
2087 breakpoint). USER_STEP indicates whether we're about to start the
2088 target for a stepping command. */
2091 internal_resume_ptid (int user_step
)
2093 /* In non-stop, we always control threads individually. Note that
2094 the target may always work in non-stop mode even with "set
2095 non-stop off", in which case user_visible_resume_ptid could
2096 return a wildcard ptid. */
2097 if (target_is_non_stop_p ())
2098 return inferior_ptid
;
2100 return user_visible_resume_ptid (user_step
);
2103 /* Wrapper for target_resume, that handles infrun-specific
2107 do_target_resume (ptid_t resume_ptid
, bool step
, enum gdb_signal sig
)
2109 struct thread_info
*tp
= inferior_thread ();
2111 gdb_assert (!tp
->stop_requested
);
2113 /* Install inferior's terminal modes. */
2114 target_terminal::inferior ();
2116 /* Avoid confusing the next resume, if the next stop/resume
2117 happens to apply to another thread. */
2118 tp
->set_stop_signal (GDB_SIGNAL_0
);
2120 /* Advise target which signals may be handled silently.
2122 If we have removed breakpoints because we are stepping over one
2123 in-line (in any thread), we need to receive all signals to avoid
2124 accidentally skipping a breakpoint during execution of a signal
2127 Likewise if we're displaced stepping, otherwise a trap for a
2128 breakpoint in a signal handler might be confused with the
2129 displaced step finishing. We don't make the displaced_step_finish
2130 step distinguish the cases instead, because:
2132 - a backtrace while stopped in the signal handler would show the
2133 scratch pad as frame older than the signal handler, instead of
2134 the real mainline code.
2136 - when the thread is later resumed, the signal handler would
2137 return to the scratch pad area, which would no longer be
2139 if (step_over_info_valid_p ()
2140 || displaced_step_in_progress (tp
->inf
))
2141 target_pass_signals ({});
2143 target_pass_signals (signal_pass
);
2145 target_resume (resume_ptid
, step
, sig
);
2147 if (target_can_async_p ())
2151 /* Resume the inferior. SIG is the signal to give the inferior
2152 (GDB_SIGNAL_0 for none). Note: don't call this directly; instead
2153 call 'resume', which handles exceptions. */
2156 resume_1 (enum gdb_signal sig
)
2158 struct regcache
*regcache
= get_current_regcache ();
2159 struct gdbarch
*gdbarch
= regcache
->arch ();
2160 struct thread_info
*tp
= inferior_thread ();
2161 const address_space
*aspace
= regcache
->aspace ();
2163 /* This represents the user's step vs continue request. When
2164 deciding whether "set scheduler-locking step" applies, it's the
2165 user's intention that counts. */
2166 const int user_step
= tp
->control
.stepping_command
;
2167 /* This represents what we'll actually request the target to do.
2168 This can decay from a step to a continue, if e.g., we need to
2169 implement single-stepping with breakpoints (software
2173 gdb_assert (!tp
->stop_requested
);
2174 gdb_assert (!thread_is_in_step_over_chain (tp
));
2176 if (tp
->has_pending_waitstatus ())
2179 ("thread %s has pending wait "
2180 "status %s (currently_stepping=%d).",
2181 target_pid_to_str (tp
->ptid
).c_str (),
2182 target_waitstatus_to_string (&tp
->pending_waitstatus ()).c_str (),
2183 currently_stepping (tp
));
2185 tp
->inf
->process_target ()->threads_executing
= true;
2186 tp
->set_resumed (true);
2188 /* FIXME: What should we do if we are supposed to resume this
2189 thread with a signal? Maybe we should maintain a queue of
2190 pending signals to deliver. */
2191 if (sig
!= GDB_SIGNAL_0
)
2193 warning (_("Couldn't deliver signal %s to %s."),
2194 gdb_signal_to_name (sig
),
2195 target_pid_to_str (tp
->ptid
).c_str ());
2198 tp
->set_stop_signal (GDB_SIGNAL_0
);
2200 if (target_can_async_p ())
2203 /* Tell the event loop we have an event to process. */
2204 mark_async_event_handler (infrun_async_inferior_event_token
);
2209 tp
->stepped_breakpoint
= 0;
2211 /* Depends on stepped_breakpoint. */
2212 step
= currently_stepping (tp
);
2214 if (current_inferior ()->waiting_for_vfork_done
)
2216 /* Don't try to single-step a vfork parent that is waiting for
2217 the child to get out of the shared memory region (by exec'ing
2218 or exiting). This is particularly important on software
2219 single-step archs, as the child process would trip on the
2220 software single step breakpoint inserted for the parent
2221 process. Since the parent will not actually execute any
2222 instruction until the child is out of the shared region (such
2223 are vfork's semantics), it is safe to simply continue it.
2224 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2225 the parent, and tell it to `keep_going', which automatically
2226 re-sets it stepping. */
2227 infrun_debug_printf ("resume : clear step");
2231 CORE_ADDR pc
= regcache_read_pc (regcache
);
2233 infrun_debug_printf ("step=%d, signal=%s, trap_expected=%d, "
2234 "current thread [%s] at %s",
2235 step
, gdb_signal_to_symbol_string (sig
),
2236 tp
->control
.trap_expected
,
2237 target_pid_to_str (inferior_ptid
).c_str (),
2238 paddress (gdbarch
, pc
));
2240 /* Normally, by the time we reach `resume', the breakpoints are either
2241 removed or inserted, as appropriate. The exception is if we're sitting
2242 at a permanent breakpoint; we need to step over it, but permanent
2243 breakpoints can't be removed. So we have to test for it here. */
2244 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2246 if (sig
!= GDB_SIGNAL_0
)
2248 /* We have a signal to pass to the inferior. The resume
2249 may, or may not take us to the signal handler. If this
2250 is a step, we'll need to stop in the signal handler, if
2251 there's one, (if the target supports stepping into
2252 handlers), or in the next mainline instruction, if
2253 there's no handler. If this is a continue, we need to be
2254 sure to run the handler with all breakpoints inserted.
2255 In all cases, set a breakpoint at the current address
2256 (where the handler returns to), and once that breakpoint
2257 is hit, resume skipping the permanent breakpoint. If
2258 that breakpoint isn't hit, then we've stepped into the
2259 signal handler (or hit some other event). We'll delete
2260 the step-resume breakpoint then. */
2262 infrun_debug_printf ("resume: skipping permanent breakpoint, "
2263 "deliver signal first");
2265 clear_step_over_info ();
2266 tp
->control
.trap_expected
= 0;
2268 if (tp
->control
.step_resume_breakpoint
== NULL
)
2270 /* Set a "high-priority" step-resume, as we don't want
2271 user breakpoints at PC to trigger (again) when this
2273 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2274 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2276 tp
->step_after_step_resume_breakpoint
= step
;
2279 insert_breakpoints ();
2283 /* There's no signal to pass, we can go ahead and skip the
2284 permanent breakpoint manually. */
2285 infrun_debug_printf ("skipping permanent breakpoint");
2286 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2287 /* Update pc to reflect the new address from which we will
2288 execute instructions. */
2289 pc
= regcache_read_pc (regcache
);
2293 /* We've already advanced the PC, so the stepping part
2294 is done. Now we need to arrange for a trap to be
2295 reported to handle_inferior_event. Set a breakpoint
2296 at the current PC, and run to it. Don't update
2297 prev_pc, because if we end in
2298 switch_back_to_stepped_thread, we want the "expected
2299 thread advanced also" branch to be taken. IOW, we
2300 don't want this thread to step further from PC
2302 gdb_assert (!step_over_info_valid_p ());
2303 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2304 insert_breakpoints ();
2306 resume_ptid
= internal_resume_ptid (user_step
);
2307 do_target_resume (resume_ptid
, false, GDB_SIGNAL_0
);
2308 tp
->set_resumed (true);
2314 /* If we have a breakpoint to step over, make sure to do a single
2315 step only. Same if we have software watchpoints. */
2316 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2317 tp
->control
.may_range_step
= 0;
2319 /* If displaced stepping is enabled, step over breakpoints by executing a
2320 copy of the instruction at a different address.
2322 We can't use displaced stepping when we have a signal to deliver;
2323 the comments for displaced_step_prepare explain why. The
2324 comments in the handle_inferior event for dealing with 'random
2325 signals' explain what we do instead.
2327 We can't use displaced stepping when we are waiting for vfork_done
2328 event, displaced stepping breaks the vfork child similarly as single
2329 step software breakpoint. */
2330 if (tp
->control
.trap_expected
2331 && use_displaced_stepping (tp
)
2332 && !step_over_info_valid_p ()
2333 && sig
== GDB_SIGNAL_0
2334 && !current_inferior ()->waiting_for_vfork_done
)
2336 displaced_step_prepare_status prepare_status
2337 = displaced_step_prepare (tp
);
2339 if (prepare_status
== DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE
)
2341 infrun_debug_printf ("Got placed in step-over queue");
2343 tp
->control
.trap_expected
= 0;
2346 else if (prepare_status
== DISPLACED_STEP_PREPARE_STATUS_CANT
)
2348 /* Fallback to stepping over the breakpoint in-line. */
2350 if (target_is_non_stop_p ())
2351 stop_all_threads ();
2353 set_step_over_info (regcache
->aspace (),
2354 regcache_read_pc (regcache
), 0, tp
->global_num
);
2356 step
= maybe_software_singlestep (gdbarch
);
2358 insert_breakpoints ();
2360 else if (prepare_status
== DISPLACED_STEP_PREPARE_STATUS_OK
)
2362 /* Update pc to reflect the new address from which we will
2363 execute instructions due to displaced stepping. */
2364 pc
= regcache_read_pc (get_thread_regcache (tp
));
2366 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
);
2369 gdb_assert_not_reached (_("Invalid displaced_step_prepare_status "
2373 /* Do we need to do it the hard way, w/temp breakpoints? */
2375 step
= maybe_software_singlestep (gdbarch
);
2377 /* Currently, our software single-step implementation leads to different
2378 results than hardware single-stepping in one situation: when stepping
2379 into delivering a signal which has an associated signal handler,
2380 hardware single-step will stop at the first instruction of the handler,
2381 while software single-step will simply skip execution of the handler.
2383 For now, this difference in behavior is accepted since there is no
2384 easy way to actually implement single-stepping into a signal handler
2385 without kernel support.
2387 However, there is one scenario where this difference leads to follow-on
2388 problems: if we're stepping off a breakpoint by removing all breakpoints
2389 and then single-stepping. In this case, the software single-step
2390 behavior means that even if there is a *breakpoint* in the signal
2391 handler, GDB still would not stop.
2393 Fortunately, we can at least fix this particular issue. We detect
2394 here the case where we are about to deliver a signal while software
2395 single-stepping with breakpoints removed. In this situation, we
2396 revert the decisions to remove all breakpoints and insert single-
2397 step breakpoints, and instead we install a step-resume breakpoint
2398 at the current address, deliver the signal without stepping, and
2399 once we arrive back at the step-resume breakpoint, actually step
2400 over the breakpoint we originally wanted to step over. */
2401 if (thread_has_single_step_breakpoints_set (tp
)
2402 && sig
!= GDB_SIGNAL_0
2403 && step_over_info_valid_p ())
2405 /* If we have nested signals or a pending signal is delivered
2406 immediately after a handler returns, might already have
2407 a step-resume breakpoint set on the earlier handler. We cannot
2408 set another step-resume breakpoint; just continue on until the
2409 original breakpoint is hit. */
2410 if (tp
->control
.step_resume_breakpoint
== NULL
)
2412 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2413 tp
->step_after_step_resume_breakpoint
= 1;
2416 delete_single_step_breakpoints (tp
);
2418 clear_step_over_info ();
2419 tp
->control
.trap_expected
= 0;
2421 insert_breakpoints ();
2424 /* If STEP is set, it's a request to use hardware stepping
2425 facilities. But in that case, we should never
2426 use singlestep breakpoint. */
2427 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2429 /* Decide the set of threads to ask the target to resume. */
2430 if (tp
->control
.trap_expected
)
2432 /* We're allowing a thread to run past a breakpoint it has
2433 hit, either by single-stepping the thread with the breakpoint
2434 removed, or by displaced stepping, with the breakpoint inserted.
2435 In the former case, we need to single-step only this thread,
2436 and keep others stopped, as they can miss this breakpoint if
2437 allowed to run. That's not really a problem for displaced
2438 stepping, but, we still keep other threads stopped, in case
2439 another thread is also stopped for a breakpoint waiting for
2440 its turn in the displaced stepping queue. */
2441 resume_ptid
= inferior_ptid
;
2444 resume_ptid
= internal_resume_ptid (user_step
);
2446 if (execution_direction
!= EXEC_REVERSE
2447 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2449 /* There are two cases where we currently need to step a
2450 breakpoint instruction when we have a signal to deliver:
2452 - See handle_signal_stop where we handle random signals that
2453 could take out us out of the stepping range. Normally, in
2454 that case we end up continuing (instead of stepping) over the
2455 signal handler with a breakpoint at PC, but there are cases
2456 where we should _always_ single-step, even if we have a
2457 step-resume breakpoint, like when a software watchpoint is
2458 set. Assuming single-stepping and delivering a signal at the
2459 same time would takes us to the signal handler, then we could
2460 have removed the breakpoint at PC to step over it. However,
2461 some hardware step targets (like e.g., Mac OS) can't step
2462 into signal handlers, and for those, we need to leave the
2463 breakpoint at PC inserted, as otherwise if the handler
2464 recurses and executes PC again, it'll miss the breakpoint.
2465 So we leave the breakpoint inserted anyway, but we need to
2466 record that we tried to step a breakpoint instruction, so
2467 that adjust_pc_after_break doesn't end up confused.
2469 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2470 in one thread after another thread that was stepping had been
2471 momentarily paused for a step-over. When we re-resume the
2472 stepping thread, it may be resumed from that address with a
2473 breakpoint that hasn't trapped yet. Seen with
2474 gdb.threads/non-stop-fair-events.exp, on targets that don't
2475 do displaced stepping. */
2477 infrun_debug_printf ("resume: [%s] stepped breakpoint",
2478 target_pid_to_str (tp
->ptid
).c_str ());
2480 tp
->stepped_breakpoint
= 1;
2482 /* Most targets can step a breakpoint instruction, thus
2483 executing it normally. But if this one cannot, just
2484 continue and we will hit it anyway. */
2485 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2490 && tp
->control
.trap_expected
2491 && use_displaced_stepping (tp
)
2492 && !step_over_info_valid_p ())
2494 struct regcache
*resume_regcache
= get_thread_regcache (tp
);
2495 struct gdbarch
*resume_gdbarch
= resume_regcache
->arch ();
2496 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2499 read_memory (actual_pc
, buf
, sizeof (buf
));
2500 displaced_debug_printf ("run %s: %s",
2501 paddress (resume_gdbarch
, actual_pc
),
2502 displaced_step_dump_bytes
2503 (buf
, sizeof (buf
)).c_str ());
2506 if (tp
->control
.may_range_step
)
2508 /* If we're resuming a thread with the PC out of the step
2509 range, then we're doing some nested/finer run control
2510 operation, like stepping the thread out of the dynamic
2511 linker or the displaced stepping scratch pad. We
2512 shouldn't have allowed a range step then. */
2513 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2516 do_target_resume (resume_ptid
, step
, sig
);
2517 tp
->set_resumed (true);
2520 /* Resume the inferior. SIG is the signal to give the inferior
2521 (GDB_SIGNAL_0 for none). This is a wrapper around 'resume_1' that
2522 rolls back state on error. */
2525 resume (gdb_signal sig
)
2531 catch (const gdb_exception
&ex
)
2533 /* If resuming is being aborted for any reason, delete any
2534 single-step breakpoint resume_1 may have created, to avoid
2535 confusing the following resumption, and to avoid leaving
2536 single-step breakpoints perturbing other threads, in case
2537 we're running in non-stop mode. */
2538 if (inferior_ptid
!= null_ptid
)
2539 delete_single_step_breakpoints (inferior_thread ());
2549 /* Counter that tracks number of user visible stops. This can be used
2550 to tell whether a command has proceeded the inferior past the
2551 current location. This allows e.g., inferior function calls in
2552 breakpoint commands to not interrupt the command list. When the
2553 call finishes successfully, the inferior is standing at the same
2554 breakpoint as if nothing happened (and so we don't call
2556 static ULONGEST current_stop_id
;
2563 return current_stop_id
;
2566 /* Called when we report a user visible stop. */
2574 /* Clear out all variables saying what to do when inferior is continued.
2575 First do this, then set the ones you want, then call `proceed'. */
2578 clear_proceed_status_thread (struct thread_info
*tp
)
2580 infrun_debug_printf ("%s", target_pid_to_str (tp
->ptid
).c_str ());
2582 /* If we're starting a new sequence, then the previous finished
2583 single-step is no longer relevant. */
2584 if (tp
->has_pending_waitstatus ())
2586 if (tp
->stop_reason () == TARGET_STOPPED_BY_SINGLE_STEP
)
2588 infrun_debug_printf ("pending event of %s was a finished step. "
2590 target_pid_to_str (tp
->ptid
).c_str ());
2592 tp
->clear_pending_waitstatus ();
2593 tp
->set_stop_reason (TARGET_STOPPED_BY_NO_REASON
);
2598 ("thread %s has pending wait status %s (currently_stepping=%d).",
2599 target_pid_to_str (tp
->ptid
).c_str (),
2600 target_waitstatus_to_string (&tp
->pending_waitstatus ()).c_str (),
2601 currently_stepping (tp
));
2605 /* If this signal should not be seen by program, give it zero.
2606 Used for debugging signals. */
2607 if (!signal_pass_state (tp
->stop_signal ()))
2608 tp
->set_stop_signal (GDB_SIGNAL_0
);
2610 delete tp
->thread_fsm
;
2611 tp
->thread_fsm
= NULL
;
2613 tp
->control
.trap_expected
= 0;
2614 tp
->control
.step_range_start
= 0;
2615 tp
->control
.step_range_end
= 0;
2616 tp
->control
.may_range_step
= 0;
2617 tp
->control
.step_frame_id
= null_frame_id
;
2618 tp
->control
.step_stack_frame_id
= null_frame_id
;
2619 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2620 tp
->control
.step_start_function
= NULL
;
2621 tp
->stop_requested
= 0;
2623 tp
->control
.stop_step
= 0;
2625 tp
->control
.proceed_to_finish
= 0;
2627 tp
->control
.stepping_command
= 0;
2629 /* Discard any remaining commands or status from previous stop. */
2630 bpstat_clear (&tp
->control
.stop_bpstat
);
2634 clear_proceed_status (int step
)
2636 /* With scheduler-locking replay, stop replaying other threads if we're
2637 not replaying the user-visible resume ptid.
2639 This is a convenience feature to not require the user to explicitly
2640 stop replaying the other threads. We're assuming that the user's
2641 intent is to resume tracing the recorded process. */
2642 if (!non_stop
&& scheduler_mode
== schedlock_replay
2643 && target_record_is_replaying (minus_one_ptid
)
2644 && !target_record_will_replay (user_visible_resume_ptid (step
),
2645 execution_direction
))
2646 target_record_stop_replaying ();
2648 if (!non_stop
&& inferior_ptid
!= null_ptid
)
2650 ptid_t resume_ptid
= user_visible_resume_ptid (step
);
2651 process_stratum_target
*resume_target
2652 = user_visible_resume_target (resume_ptid
);
2654 /* In all-stop mode, delete the per-thread status of all threads
2655 we're about to resume, implicitly and explicitly. */
2656 for (thread_info
*tp
: all_non_exited_threads (resume_target
, resume_ptid
))
2657 clear_proceed_status_thread (tp
);
2660 if (inferior_ptid
!= null_ptid
)
2662 struct inferior
*inferior
;
2666 /* If in non-stop mode, only delete the per-thread status of
2667 the current thread. */
2668 clear_proceed_status_thread (inferior_thread ());
2671 inferior
= current_inferior ();
2672 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2675 gdb::observers::about_to_proceed
.notify ();
2678 /* Returns true if TP is still stopped at a breakpoint that needs
2679 stepping-over in order to make progress. If the breakpoint is gone
2680 meanwhile, we can skip the whole step-over dance. */
2683 thread_still_needs_step_over_bp (struct thread_info
*tp
)
2685 if (tp
->stepping_over_breakpoint
)
2687 struct regcache
*regcache
= get_thread_regcache (tp
);
2689 if (breakpoint_here_p (regcache
->aspace (),
2690 regcache_read_pc (regcache
))
2691 == ordinary_breakpoint_here
)
2694 tp
->stepping_over_breakpoint
= 0;
2700 /* Check whether thread TP still needs to start a step-over in order
2701 to make progress when resumed. Returns an bitwise or of enum
2702 step_over_what bits, indicating what needs to be stepped over. */
2704 static step_over_what
2705 thread_still_needs_step_over (struct thread_info
*tp
)
2707 step_over_what what
= 0;
2709 if (thread_still_needs_step_over_bp (tp
))
2710 what
|= STEP_OVER_BREAKPOINT
;
2712 if (tp
->stepping_over_watchpoint
2713 && !target_have_steppable_watchpoint ())
2714 what
|= STEP_OVER_WATCHPOINT
;
2719 /* Returns true if scheduler locking applies. STEP indicates whether
2720 we're about to do a step/next-like command to a thread. */
2723 schedlock_applies (struct thread_info
*tp
)
2725 return (scheduler_mode
== schedlock_on
2726 || (scheduler_mode
== schedlock_step
2727 && tp
->control
.stepping_command
)
2728 || (scheduler_mode
== schedlock_replay
2729 && target_record_will_replay (minus_one_ptid
,
2730 execution_direction
)));
2733 /* Set process_stratum_target::COMMIT_RESUMED_STATE in all target
2734 stacks that have threads executing and don't have threads with
2738 maybe_set_commit_resumed_all_targets ()
2740 scoped_restore_current_thread restore_thread
;
2742 for (inferior
*inf
: all_non_exited_inferiors ())
2744 process_stratum_target
*proc_target
= inf
->process_target ();
2746 if (proc_target
->commit_resumed_state
)
2748 /* We already set this in a previous iteration, via another
2749 inferior sharing the process_stratum target. */
2753 /* If the target has no resumed threads, it would be useless to
2754 ask it to commit the resumed threads. */
2755 if (!proc_target
->threads_executing
)
2757 infrun_debug_printf ("not requesting commit-resumed for target "
2758 "%s, no resumed threads",
2759 proc_target
->shortname ());
2763 /* As an optimization, if a thread from this target has some
2764 status to report, handle it before requiring the target to
2765 commit its resumed threads: handling the status might lead to
2766 resuming more threads. */
2767 if (proc_target
->has_resumed_with_pending_wait_status ())
2769 infrun_debug_printf ("not requesting commit-resumed for target %s, a"
2770 " thread has a pending waitstatus",
2771 proc_target
->shortname ());
2775 switch_to_inferior_no_thread (inf
);
2777 if (target_has_pending_events ())
2779 infrun_debug_printf ("not requesting commit-resumed for target %s, "
2780 "target has pending events",
2781 proc_target
->shortname ());
2785 infrun_debug_printf ("enabling commit-resumed for target %s",
2786 proc_target
->shortname ());
2788 proc_target
->commit_resumed_state
= true;
2795 maybe_call_commit_resumed_all_targets ()
2797 scoped_restore_current_thread restore_thread
;
2799 for (inferior
*inf
: all_non_exited_inferiors ())
2801 process_stratum_target
*proc_target
= inf
->process_target ();
2803 if (!proc_target
->commit_resumed_state
)
2806 switch_to_inferior_no_thread (inf
);
2808 infrun_debug_printf ("calling commit_resumed for target %s",
2809 proc_target
->shortname());
2811 target_commit_resumed ();
2815 /* To track nesting of scoped_disable_commit_resumed objects, ensuring
2816 that only the outermost one attempts to re-enable
2818 static bool enable_commit_resumed
= true;
2822 scoped_disable_commit_resumed::scoped_disable_commit_resumed
2823 (const char *reason
)
2824 : m_reason (reason
),
2825 m_prev_enable_commit_resumed (enable_commit_resumed
)
2827 infrun_debug_printf ("reason=%s", m_reason
);
2829 enable_commit_resumed
= false;
2831 for (inferior
*inf
: all_non_exited_inferiors ())
2833 process_stratum_target
*proc_target
= inf
->process_target ();
2835 if (m_prev_enable_commit_resumed
)
2837 /* This is the outermost instance: force all
2838 COMMIT_RESUMED_STATE to false. */
2839 proc_target
->commit_resumed_state
= false;
2843 /* This is not the outermost instance, we expect
2844 COMMIT_RESUMED_STATE to have been cleared by the
2845 outermost instance. */
2846 gdb_assert (!proc_target
->commit_resumed_state
);
2854 scoped_disable_commit_resumed::reset ()
2860 infrun_debug_printf ("reason=%s", m_reason
);
2862 gdb_assert (!enable_commit_resumed
);
2864 enable_commit_resumed
= m_prev_enable_commit_resumed
;
2866 if (m_prev_enable_commit_resumed
)
2868 /* This is the outermost instance, re-enable
2869 COMMIT_RESUMED_STATE on the targets where it's possible. */
2870 maybe_set_commit_resumed_all_targets ();
2874 /* This is not the outermost instance, we expect
2875 COMMIT_RESUMED_STATE to still be false. */
2876 for (inferior
*inf
: all_non_exited_inferiors ())
2878 process_stratum_target
*proc_target
= inf
->process_target ();
2879 gdb_assert (!proc_target
->commit_resumed_state
);
2886 scoped_disable_commit_resumed::~scoped_disable_commit_resumed ()
2894 scoped_disable_commit_resumed::reset_and_commit ()
2897 maybe_call_commit_resumed_all_targets ();
2902 scoped_enable_commit_resumed::scoped_enable_commit_resumed
2903 (const char *reason
)
2904 : m_reason (reason
),
2905 m_prev_enable_commit_resumed (enable_commit_resumed
)
2907 infrun_debug_printf ("reason=%s", m_reason
);
2909 if (!enable_commit_resumed
)
2911 enable_commit_resumed
= true;
2913 /* Re-enable COMMIT_RESUMED_STATE on the targets where it's
2915 maybe_set_commit_resumed_all_targets ();
2917 maybe_call_commit_resumed_all_targets ();
2923 scoped_enable_commit_resumed::~scoped_enable_commit_resumed ()
2925 infrun_debug_printf ("reason=%s", m_reason
);
2927 gdb_assert (enable_commit_resumed
);
2929 enable_commit_resumed
= m_prev_enable_commit_resumed
;
2931 if (!enable_commit_resumed
)
2933 /* Force all COMMIT_RESUMED_STATE back to false. */
2934 for (inferior
*inf
: all_non_exited_inferiors ())
2936 process_stratum_target
*proc_target
= inf
->process_target ();
2937 proc_target
->commit_resumed_state
= false;
2942 /* Check that all the targets we're about to resume are in non-stop
2943 mode. Ideally, we'd only care whether all targets support
2944 target-async, but we're not there yet. E.g., stop_all_threads
2945 doesn't know how to handle all-stop targets. Also, the remote
2946 protocol in all-stop mode is synchronous, irrespective of
2947 target-async, which means that things like a breakpoint re-set
2948 triggered by one target would try to read memory from all targets
2952 check_multi_target_resumption (process_stratum_target
*resume_target
)
2954 if (!non_stop
&& resume_target
== nullptr)
2956 scoped_restore_current_thread restore_thread
;
2958 /* This is used to track whether we're resuming more than one
2960 process_stratum_target
*first_connection
= nullptr;
2962 /* The first inferior we see with a target that does not work in
2963 always-non-stop mode. */
2964 inferior
*first_not_non_stop
= nullptr;
2966 for (inferior
*inf
: all_non_exited_inferiors ())
2968 switch_to_inferior_no_thread (inf
);
2970 if (!target_has_execution ())
2973 process_stratum_target
*proc_target
2974 = current_inferior ()->process_target();
2976 if (!target_is_non_stop_p ())
2977 first_not_non_stop
= inf
;
2979 if (first_connection
== nullptr)
2980 first_connection
= proc_target
;
2981 else if (first_connection
!= proc_target
2982 && first_not_non_stop
!= nullptr)
2984 switch_to_inferior_no_thread (first_not_non_stop
);
2986 proc_target
= current_inferior ()->process_target();
2988 error (_("Connection %d (%s) does not support "
2989 "multi-target resumption."),
2990 proc_target
->connection_number
,
2991 make_target_connection_string (proc_target
).c_str ());
2997 /* Basic routine for continuing the program in various fashions.
2999 ADDR is the address to resume at, or -1 for resume where stopped.
3000 SIGGNAL is the signal to give it, or GDB_SIGNAL_0 for none,
3001 or GDB_SIGNAL_DEFAULT for act according to how it stopped.
3003 You should call clear_proceed_status before calling proceed. */
3006 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
)
3008 INFRUN_SCOPED_DEBUG_ENTER_EXIT
;
3010 struct regcache
*regcache
;
3011 struct gdbarch
*gdbarch
;
3013 struct execution_control_state ecss
;
3014 struct execution_control_state
*ecs
= &ecss
;
3017 /* If we're stopped at a fork/vfork, follow the branch set by the
3018 "set follow-fork-mode" command; otherwise, we'll just proceed
3019 resuming the current thread. */
3020 if (!follow_fork ())
3022 /* The target for some reason decided not to resume. */
3024 if (target_can_async_p ())
3025 inferior_event_handler (INF_EXEC_COMPLETE
);
3029 /* We'll update this if & when we switch to a new thread. */
3030 previous_inferior_ptid
= inferior_ptid
;
3032 regcache
= get_current_regcache ();
3033 gdbarch
= regcache
->arch ();
3034 const address_space
*aspace
= regcache
->aspace ();
3036 pc
= regcache_read_pc_protected (regcache
);
3038 thread_info
*cur_thr
= inferior_thread ();
3040 /* Fill in with reasonable starting values. */
3041 init_thread_stepping_state (cur_thr
);
3043 gdb_assert (!thread_is_in_step_over_chain (cur_thr
));
3046 = user_visible_resume_ptid (cur_thr
->control
.stepping_command
);
3047 process_stratum_target
*resume_target
3048 = user_visible_resume_target (resume_ptid
);
3050 check_multi_target_resumption (resume_target
);
3052 if (addr
== (CORE_ADDR
) -1)
3054 if (cur_thr
->stop_pc_p ()
3055 && pc
== cur_thr
->stop_pc ()
3056 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
3057 && execution_direction
!= EXEC_REVERSE
)
3058 /* There is a breakpoint at the address we will resume at,
3059 step one instruction before inserting breakpoints so that
3060 we do not stop right away (and report a second hit at this
3063 Note, we don't do this in reverse, because we won't
3064 actually be executing the breakpoint insn anyway.
3065 We'll be (un-)executing the previous instruction. */
3066 cur_thr
->stepping_over_breakpoint
= 1;
3067 else if (gdbarch_single_step_through_delay_p (gdbarch
)
3068 && gdbarch_single_step_through_delay (gdbarch
,
3069 get_current_frame ()))
3070 /* We stepped onto an instruction that needs to be stepped
3071 again before re-inserting the breakpoint, do so. */
3072 cur_thr
->stepping_over_breakpoint
= 1;
3076 regcache_write_pc (regcache
, addr
);
3079 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
3080 cur_thr
->set_stop_signal (siggnal
);
3082 /* If an exception is thrown from this point on, make sure to
3083 propagate GDB's knowledge of the executing state to the
3084 frontend/user running state. */
3085 scoped_finish_thread_state
finish_state (resume_target
, resume_ptid
);
3087 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
3088 threads (e.g., we might need to set threads stepping over
3089 breakpoints first), from the user/frontend's point of view, all
3090 threads in RESUME_PTID are now running. Unless we're calling an
3091 inferior function, as in that case we pretend the inferior
3092 doesn't run at all. */
3093 if (!cur_thr
->control
.in_infcall
)
3094 set_running (resume_target
, resume_ptid
, true);
3096 infrun_debug_printf ("addr=%s, signal=%s", paddress (gdbarch
, addr
),
3097 gdb_signal_to_symbol_string (siggnal
));
3099 annotate_starting ();
3101 /* Make sure that output from GDB appears before output from the
3103 gdb_flush (gdb_stdout
);
3105 /* Since we've marked the inferior running, give it the terminal. A
3106 QUIT/Ctrl-C from here on is forwarded to the target (which can
3107 still detect attempts to unblock a stuck connection with repeated
3108 Ctrl-C from within target_pass_ctrlc). */
3109 target_terminal::inferior ();
3111 /* In a multi-threaded task we may select another thread and
3112 then continue or step.
3114 But if a thread that we're resuming had stopped at a breakpoint,
3115 it will immediately cause another breakpoint stop without any
3116 execution (i.e. it will report a breakpoint hit incorrectly). So
3117 we must step over it first.
3119 Look for threads other than the current (TP) that reported a
3120 breakpoint hit and haven't been resumed yet since. */
3122 /* If scheduler locking applies, we can avoid iterating over all
3124 if (!non_stop
&& !schedlock_applies (cur_thr
))
3126 for (thread_info
*tp
: all_non_exited_threads (resume_target
,
3129 switch_to_thread_no_regs (tp
);
3131 /* Ignore the current thread here. It's handled
3136 if (!thread_still_needs_step_over (tp
))
3139 gdb_assert (!thread_is_in_step_over_chain (tp
));
3141 infrun_debug_printf ("need to step-over [%s] first",
3142 target_pid_to_str (tp
->ptid
).c_str ());
3144 global_thread_step_over_chain_enqueue (tp
);
3147 switch_to_thread (cur_thr
);
3150 /* Enqueue the current thread last, so that we move all other
3151 threads over their breakpoints first. */
3152 if (cur_thr
->stepping_over_breakpoint
)
3153 global_thread_step_over_chain_enqueue (cur_thr
);
3155 /* If the thread isn't started, we'll still need to set its prev_pc,
3156 so that switch_back_to_stepped_thread knows the thread hasn't
3157 advanced. Must do this before resuming any thread, as in
3158 all-stop/remote, once we resume we can't send any other packet
3159 until the target stops again. */
3160 cur_thr
->prev_pc
= regcache_read_pc_protected (regcache
);
3163 scoped_disable_commit_resumed
disable_commit_resumed ("proceeding");
3165 started
= start_step_over ();
3167 if (step_over_info_valid_p ())
3169 /* Either this thread started a new in-line step over, or some
3170 other thread was already doing one. In either case, don't
3171 resume anything else until the step-over is finished. */
3173 else if (started
&& !target_is_non_stop_p ())
3175 /* A new displaced stepping sequence was started. In all-stop,
3176 we can't talk to the target anymore until it next stops. */
3178 else if (!non_stop
&& target_is_non_stop_p ())
3180 INFRUN_SCOPED_DEBUG_START_END
3181 ("resuming threads, all-stop-on-top-of-non-stop");
3183 /* In all-stop, but the target is always in non-stop mode.
3184 Start all other threads that are implicitly resumed too. */
3185 for (thread_info
*tp
: all_non_exited_threads (resume_target
,
3188 switch_to_thread_no_regs (tp
);
3190 if (!tp
->inf
->has_execution ())
3192 infrun_debug_printf ("[%s] target has no execution",
3193 target_pid_to_str (tp
->ptid
).c_str ());
3199 infrun_debug_printf ("[%s] resumed",
3200 target_pid_to_str (tp
->ptid
).c_str ());
3201 gdb_assert (tp
->executing () || tp
->has_pending_waitstatus ());
3205 if (thread_is_in_step_over_chain (tp
))
3207 infrun_debug_printf ("[%s] needs step-over",
3208 target_pid_to_str (tp
->ptid
).c_str ());
3212 infrun_debug_printf ("resuming %s",
3213 target_pid_to_str (tp
->ptid
).c_str ());
3215 reset_ecs (ecs
, tp
);
3216 switch_to_thread (tp
);
3217 keep_going_pass_signal (ecs
);
3218 if (!ecs
->wait_some_more
)
3219 error (_("Command aborted."));
3222 else if (!cur_thr
->resumed () && !thread_is_in_step_over_chain (cur_thr
))
3224 /* The thread wasn't started, and isn't queued, run it now. */
3225 reset_ecs (ecs
, cur_thr
);
3226 switch_to_thread (cur_thr
);
3227 keep_going_pass_signal (ecs
);
3228 if (!ecs
->wait_some_more
)
3229 error (_("Command aborted."));
3232 disable_commit_resumed
.reset_and_commit ();
3235 finish_state
.release ();
3237 /* If we've switched threads above, switch back to the previously
3238 current thread. We don't want the user to see a different
3240 switch_to_thread (cur_thr
);
3242 /* Tell the event loop to wait for it to stop. If the target
3243 supports asynchronous execution, it'll do this from within
3245 if (!target_can_async_p ())
3246 mark_async_event_handler (infrun_async_inferior_event_token
);
3250 /* Start remote-debugging of a machine over a serial link. */
3253 start_remote (int from_tty
)
3255 inferior
*inf
= current_inferior ();
3256 inf
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
3258 /* Always go on waiting for the target, regardless of the mode. */
3259 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3260 indicate to wait_for_inferior that a target should timeout if
3261 nothing is returned (instead of just blocking). Because of this,
3262 targets expecting an immediate response need to, internally, set
3263 things up so that the target_wait() is forced to eventually
3265 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3266 differentiate to its caller what the state of the target is after
3267 the initial open has been performed. Here we're assuming that
3268 the target has stopped. It should be possible to eventually have
3269 target_open() return to the caller an indication that the target
3270 is currently running and GDB state should be set to the same as
3271 for an async run. */
3272 wait_for_inferior (inf
);
3274 /* Now that the inferior has stopped, do any bookkeeping like
3275 loading shared libraries. We want to do this before normal_stop,
3276 so that the displayed frame is up to date. */
3277 post_create_inferior (from_tty
);
3282 /* Initialize static vars when a new inferior begins. */
3285 init_wait_for_inferior (void)
3287 /* These are meaningless until the first time through wait_for_inferior. */
3289 breakpoint_init_inferior (inf_starting
);
3291 clear_proceed_status (0);
3293 nullify_last_target_wait_ptid ();
3295 previous_inferior_ptid
= inferior_ptid
;
3300 static void handle_inferior_event (struct execution_control_state
*ecs
);
3302 static void handle_step_into_function (struct gdbarch
*gdbarch
,
3303 struct execution_control_state
*ecs
);
3304 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
3305 struct execution_control_state
*ecs
);
3306 static void handle_signal_stop (struct execution_control_state
*ecs
);
3307 static void check_exception_resume (struct execution_control_state
*,
3308 struct frame_info
*);
3310 static void end_stepping_range (struct execution_control_state
*ecs
);
3311 static void stop_waiting (struct execution_control_state
*ecs
);
3312 static void keep_going (struct execution_control_state
*ecs
);
3313 static void process_event_stop_test (struct execution_control_state
*ecs
);
3314 static bool switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
3316 /* This function is attached as a "thread_stop_requested" observer.
3317 Cleanup local state that assumed the PTID was to be resumed, and
3318 report the stop to the frontend. */
3321 infrun_thread_stop_requested (ptid_t ptid
)
3323 process_stratum_target
*curr_target
= current_inferior ()->process_target ();
3325 /* PTID was requested to stop. If the thread was already stopped,
3326 but the user/frontend doesn't know about that yet (e.g., the
3327 thread had been temporarily paused for some step-over), set up
3328 for reporting the stop now. */
3329 for (thread_info
*tp
: all_threads (curr_target
, ptid
))
3331 if (tp
->state
!= THREAD_RUNNING
)
3333 if (tp
->executing ())
3336 /* Remove matching threads from the step-over queue, so
3337 start_step_over doesn't try to resume them
3339 if (thread_is_in_step_over_chain (tp
))
3340 global_thread_step_over_chain_remove (tp
);
3342 /* If the thread is stopped, but the user/frontend doesn't
3343 know about that yet, queue a pending event, as if the
3344 thread had just stopped now. Unless the thread already had
3346 if (!tp
->has_pending_waitstatus ())
3348 target_waitstatus ws
;
3349 ws
.kind
= TARGET_WAITKIND_STOPPED
;
3350 ws
.value
.sig
= GDB_SIGNAL_0
;
3351 tp
->set_pending_waitstatus (ws
);
3354 /* Clear the inline-frame state, since we're re-processing the
3356 clear_inline_frame_state (tp
);
3358 /* If this thread was paused because some other thread was
3359 doing an inline-step over, let that finish first. Once
3360 that happens, we'll restart all threads and consume pending
3361 stop events then. */
3362 if (step_over_info_valid_p ())
3365 /* Otherwise we can process the (new) pending event now. Set
3366 it so this pending event is considered by
3368 tp
->set_resumed (true);
3373 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
3375 if (target_last_proc_target
== tp
->inf
->process_target ()
3376 && target_last_wait_ptid
== tp
->ptid
)
3377 nullify_last_target_wait_ptid ();
3380 /* Delete the step resume, single-step and longjmp/exception resume
3381 breakpoints of TP. */
3384 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
3386 delete_step_resume_breakpoint (tp
);
3387 delete_exception_resume_breakpoint (tp
);
3388 delete_single_step_breakpoints (tp
);
3391 /* If the target still has execution, call FUNC for each thread that
3392 just stopped. In all-stop, that's all the non-exited threads; in
3393 non-stop, that's the current thread, only. */
3395 typedef void (*for_each_just_stopped_thread_callback_func
)
3396 (struct thread_info
*tp
);
3399 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
3401 if (!target_has_execution () || inferior_ptid
== null_ptid
)
3404 if (target_is_non_stop_p ())
3406 /* If in non-stop mode, only the current thread stopped. */
3407 func (inferior_thread ());
3411 /* In all-stop mode, all threads have stopped. */
3412 for (thread_info
*tp
: all_non_exited_threads ())
3417 /* Delete the step resume and longjmp/exception resume breakpoints of
3418 the threads that just stopped. */
3421 delete_just_stopped_threads_infrun_breakpoints (void)
3423 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3426 /* Delete the single-step breakpoints of the threads that just
3430 delete_just_stopped_threads_single_step_breakpoints (void)
3432 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3438 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3439 const struct target_waitstatus
*ws
)
3441 infrun_debug_printf ("target_wait (%s [%s], status) =",
3442 waiton_ptid
.to_string ().c_str (),
3443 target_pid_to_str (waiton_ptid
).c_str ());
3444 infrun_debug_printf (" %s [%s],",
3445 result_ptid
.to_string ().c_str (),
3446 target_pid_to_str (result_ptid
).c_str ());
3447 infrun_debug_printf (" %s", target_waitstatus_to_string (ws
).c_str ());
3450 /* Select a thread at random, out of those which are resumed and have
3453 static struct thread_info
*
3454 random_pending_event_thread (inferior
*inf
, ptid_t waiton_ptid
)
3456 process_stratum_target
*proc_target
= inf
->process_target ();
3458 = proc_target
->random_resumed_with_pending_wait_status (inf
, waiton_ptid
);
3460 if (thread
== nullptr)
3462 infrun_debug_printf ("None found.");
3466 infrun_debug_printf ("Found %s.", target_pid_to_str (thread
->ptid
).c_str ());
3467 gdb_assert (thread
->resumed ());
3468 gdb_assert (thread
->has_pending_waitstatus ());
3473 /* Wrapper for target_wait that first checks whether threads have
3474 pending statuses to report before actually asking the target for
3475 more events. INF is the inferior we're using to call target_wait
3479 do_target_wait_1 (inferior
*inf
, ptid_t ptid
,
3480 target_waitstatus
*status
, target_wait_flags options
)
3483 struct thread_info
*tp
;
3485 /* We know that we are looking for an event in the target of inferior
3486 INF, but we don't know which thread the event might come from. As
3487 such we want to make sure that INFERIOR_PTID is reset so that none of
3488 the wait code relies on it - doing so is always a mistake. */
3489 switch_to_inferior_no_thread (inf
);
3491 /* First check if there is a resumed thread with a wait status
3493 if (ptid
== minus_one_ptid
|| ptid
.is_pid ())
3495 tp
= random_pending_event_thread (inf
, ptid
);
3499 infrun_debug_printf ("Waiting for specific thread %s.",
3500 target_pid_to_str (ptid
).c_str ());
3502 /* We have a specific thread to check. */
3503 tp
= find_thread_ptid (inf
, ptid
);
3504 gdb_assert (tp
!= NULL
);
3505 if (!tp
->has_pending_waitstatus ())
3510 && (tp
->stop_reason () == TARGET_STOPPED_BY_SW_BREAKPOINT
3511 || tp
->stop_reason () == TARGET_STOPPED_BY_HW_BREAKPOINT
))
3513 struct regcache
*regcache
= get_thread_regcache (tp
);
3514 struct gdbarch
*gdbarch
= regcache
->arch ();
3518 pc
= regcache_read_pc (regcache
);
3520 if (pc
!= tp
->stop_pc ())
3522 infrun_debug_printf ("PC of %s changed. was=%s, now=%s",
3523 target_pid_to_str (tp
->ptid
).c_str (),
3524 paddress (gdbarch
, tp
->stop_pc ()),
3525 paddress (gdbarch
, pc
));
3528 else if (!breakpoint_inserted_here_p (regcache
->aspace (), pc
))
3530 infrun_debug_printf ("previous breakpoint of %s, at %s gone",
3531 target_pid_to_str (tp
->ptid
).c_str (),
3532 paddress (gdbarch
, pc
));
3539 infrun_debug_printf ("pending event of %s cancelled.",
3540 target_pid_to_str (tp
->ptid
).c_str ());
3542 tp
->clear_pending_waitstatus ();
3543 target_waitstatus ws
;
3544 ws
.kind
= TARGET_WAITKIND_SPURIOUS
;
3545 tp
->set_pending_waitstatus (ws
);
3546 tp
->set_stop_reason (TARGET_STOPPED_BY_NO_REASON
);
3552 infrun_debug_printf ("Using pending wait status %s for %s.",
3553 target_waitstatus_to_string
3554 (&tp
->pending_waitstatus ()).c_str (),
3555 target_pid_to_str (tp
->ptid
).c_str ());
3557 /* Now that we've selected our final event LWP, un-adjust its PC
3558 if it was a software breakpoint (and the target doesn't
3559 always adjust the PC itself). */
3560 if (tp
->stop_reason () == TARGET_STOPPED_BY_SW_BREAKPOINT
3561 && !target_supports_stopped_by_sw_breakpoint ())
3563 struct regcache
*regcache
;
3564 struct gdbarch
*gdbarch
;
3567 regcache
= get_thread_regcache (tp
);
3568 gdbarch
= regcache
->arch ();
3570 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3575 pc
= regcache_read_pc (regcache
);
3576 regcache_write_pc (regcache
, pc
+ decr_pc
);
3580 tp
->set_stop_reason (TARGET_STOPPED_BY_NO_REASON
);
3581 *status
= tp
->pending_waitstatus ();
3582 tp
->clear_pending_waitstatus ();
3584 /* Wake up the event loop again, until all pending events are
3586 if (target_is_async_p ())
3587 mark_async_event_handler (infrun_async_inferior_event_token
);
3591 /* But if we don't find one, we'll have to wait. */
3593 /* We can't ask a non-async target to do a non-blocking wait, so this will be
3595 if (!target_can_async_p ())
3596 options
&= ~TARGET_WNOHANG
;
3598 if (deprecated_target_wait_hook
)
3599 event_ptid
= deprecated_target_wait_hook (ptid
, status
, options
);
3601 event_ptid
= target_wait (ptid
, status
, options
);
3606 /* Wrapper for target_wait that first checks whether threads have
3607 pending statuses to report before actually asking the target for
3608 more events. Polls for events from all inferiors/targets. */
3611 do_target_wait (execution_control_state
*ecs
, target_wait_flags options
)
3613 int num_inferiors
= 0;
3614 int random_selector
;
3616 /* For fairness, we pick the first inferior/target to poll at random
3617 out of all inferiors that may report events, and then continue
3618 polling the rest of the inferior list starting from that one in a
3619 circular fashion until the whole list is polled once. */
3621 auto inferior_matches
= [] (inferior
*inf
)
3623 return inf
->process_target () != nullptr;
3626 /* First see how many matching inferiors we have. */
3627 for (inferior
*inf
: all_inferiors ())
3628 if (inferior_matches (inf
))
3631 if (num_inferiors
== 0)
3633 ecs
->ws
.kind
= TARGET_WAITKIND_IGNORE
;
3637 /* Now randomly pick an inferior out of those that matched. */
3638 random_selector
= (int)
3639 ((num_inferiors
* (double) rand ()) / (RAND_MAX
+ 1.0));
3641 if (num_inferiors
> 1)
3642 infrun_debug_printf ("Found %d inferiors, starting at #%d",
3643 num_inferiors
, random_selector
);
3645 /* Select the Nth inferior that matched. */
3647 inferior
*selected
= nullptr;
3649 for (inferior
*inf
: all_inferiors ())
3650 if (inferior_matches (inf
))
3651 if (random_selector
-- == 0)
3657 /* Now poll for events out of each of the matching inferior's
3658 targets, starting from the selected one. */
3660 auto do_wait
= [&] (inferior
*inf
)
3662 ecs
->ptid
= do_target_wait_1 (inf
, minus_one_ptid
, &ecs
->ws
, options
);
3663 ecs
->target
= inf
->process_target ();
3664 return (ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
);
3667 /* Needed in 'all-stop + target-non-stop' mode, because we end up
3668 here spuriously after the target is all stopped and we've already
3669 reported the stop to the user, polling for events. */
3670 scoped_restore_current_thread restore_thread
;
3672 intrusive_list_iterator
<inferior
> start
3673 = inferior_list
.iterator_to (*selected
);
3675 for (intrusive_list_iterator
<inferior
> it
= start
;
3676 it
!= inferior_list
.end ();
3679 inferior
*inf
= &*it
;
3681 if (inferior_matches (inf
) && do_wait (inf
))
3685 for (intrusive_list_iterator
<inferior
> it
= inferior_list
.begin ();
3689 inferior
*inf
= &*it
;
3691 if (inferior_matches (inf
) && do_wait (inf
))
3695 ecs
->ws
.kind
= TARGET_WAITKIND_IGNORE
;
3699 /* An event reported by wait_one. */
3701 struct wait_one_event
3703 /* The target the event came out of. */
3704 process_stratum_target
*target
;
3706 /* The PTID the event was for. */
3709 /* The waitstatus. */
3710 target_waitstatus ws
;
3713 static bool handle_one (const wait_one_event
&event
);
3714 static void restart_threads (struct thread_info
*event_thread
);
3716 /* Prepare and stabilize the inferior for detaching it. E.g.,
3717 detaching while a thread is displaced stepping is a recipe for
3718 crashing it, as nothing would readjust the PC out of the scratch
3722 prepare_for_detach (void)
3724 struct inferior
*inf
= current_inferior ();
3725 ptid_t pid_ptid
= ptid_t (inf
->pid
);
3726 scoped_restore_current_thread restore_thread
;
3728 scoped_restore restore_detaching
= make_scoped_restore (&inf
->detaching
, true);
3730 /* Remove all threads of INF from the global step-over chain. We
3731 want to stop any ongoing step-over, not start any new one. */
3732 thread_step_over_list_safe_range range
3733 = make_thread_step_over_list_safe_range (global_thread_step_over_list
);
3735 for (thread_info
*tp
: range
)
3738 infrun_debug_printf ("removing thread %s from global step over chain",
3739 target_pid_to_str (tp
->ptid
).c_str ());
3740 global_thread_step_over_chain_remove (tp
);
3743 /* If we were already in the middle of an inline step-over, and the
3744 thread stepping belongs to the inferior we're detaching, we need
3745 to restart the threads of other inferiors. */
3746 if (step_over_info
.thread
!= -1)
3748 infrun_debug_printf ("inline step-over in-process while detaching");
3750 thread_info
*thr
= find_thread_global_id (step_over_info
.thread
);
3751 if (thr
->inf
== inf
)
3753 /* Since we removed threads of INF from the step-over chain,
3754 we know this won't start a step-over for INF. */
3755 clear_step_over_info ();
3757 if (target_is_non_stop_p ())
3759 /* Start a new step-over in another thread if there's
3760 one that needs it. */
3763 /* Restart all other threads (except the
3764 previously-stepping thread, since that one is still
3766 if (!step_over_info_valid_p ())
3767 restart_threads (thr
);
3772 if (displaced_step_in_progress (inf
))
3774 infrun_debug_printf ("displaced-stepping in-process while detaching");
3776 /* Stop threads currently displaced stepping, aborting it. */
3778 for (thread_info
*thr
: inf
->non_exited_threads ())
3780 if (thr
->displaced_step_state
.in_progress ())
3782 if (thr
->executing ())
3784 if (!thr
->stop_requested
)
3786 target_stop (thr
->ptid
);
3787 thr
->stop_requested
= true;
3791 thr
->set_resumed (false);
3795 while (displaced_step_in_progress (inf
))
3797 wait_one_event event
;
3799 event
.target
= inf
->process_target ();
3800 event
.ptid
= do_target_wait_1 (inf
, pid_ptid
, &event
.ws
, 0);
3803 print_target_wait_results (pid_ptid
, event
.ptid
, &event
.ws
);
3808 /* It's OK to leave some of the threads of INF stopped, since
3809 they'll be detached shortly. */
3813 /* Wait for control to return from inferior to debugger.
3815 If inferior gets a signal, we may decide to start it up again
3816 instead of returning. That is why there is a loop in this function.
3817 When this function actually returns it means the inferior
3818 should be left stopped and GDB should read more commands. */
3821 wait_for_inferior (inferior
*inf
)
3823 infrun_debug_printf ("wait_for_inferior ()");
3825 SCOPE_EXIT
{ delete_just_stopped_threads_infrun_breakpoints (); };
3827 /* If an error happens while handling the event, propagate GDB's
3828 knowledge of the executing state to the frontend/user running
3830 scoped_finish_thread_state finish_state
3831 (inf
->process_target (), minus_one_ptid
);
3835 struct execution_control_state ecss
;
3836 struct execution_control_state
*ecs
= &ecss
;
3838 memset (ecs
, 0, sizeof (*ecs
));
3840 overlay_cache_invalid
= 1;
3842 /* Flush target cache before starting to handle each event.
3843 Target was running and cache could be stale. This is just a
3844 heuristic. Running threads may modify target memory, but we
3845 don't get any event. */
3846 target_dcache_invalidate ();
3848 ecs
->ptid
= do_target_wait_1 (inf
, minus_one_ptid
, &ecs
->ws
, 0);
3849 ecs
->target
= inf
->process_target ();
3852 print_target_wait_results (minus_one_ptid
, ecs
->ptid
, &ecs
->ws
);
3854 /* Now figure out what to do with the result of the result. */
3855 handle_inferior_event (ecs
);
3857 if (!ecs
->wait_some_more
)
3861 /* No error, don't finish the state yet. */
3862 finish_state
.release ();
3865 /* Cleanup that reinstalls the readline callback handler, if the
3866 target is running in the background. If while handling the target
3867 event something triggered a secondary prompt, like e.g., a
3868 pagination prompt, we'll have removed the callback handler (see
3869 gdb_readline_wrapper_line). Need to do this as we go back to the
3870 event loop, ready to process further input. Note this has no
3871 effect if the handler hasn't actually been removed, because calling
3872 rl_callback_handler_install resets the line buffer, thus losing
3876 reinstall_readline_callback_handler_cleanup ()
3878 struct ui
*ui
= current_ui
;
3882 /* We're not going back to the top level event loop yet. Don't
3883 install the readline callback, as it'd prep the terminal,
3884 readline-style (raw, noecho) (e.g., --batch). We'll install
3885 it the next time the prompt is displayed, when we're ready
3890 if (ui
->command_editing
&& ui
->prompt_state
!= PROMPT_BLOCKED
)
3891 gdb_rl_callback_handler_reinstall ();
3894 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3895 that's just the event thread. In all-stop, that's all threads. */
3898 clean_up_just_stopped_threads_fsms (struct execution_control_state
*ecs
)
3900 if (ecs
->event_thread
!= NULL
3901 && ecs
->event_thread
->thread_fsm
!= NULL
)
3902 ecs
->event_thread
->thread_fsm
->clean_up (ecs
->event_thread
);
3906 for (thread_info
*thr
: all_non_exited_threads ())
3908 if (thr
->thread_fsm
== NULL
)
3910 if (thr
== ecs
->event_thread
)
3913 switch_to_thread (thr
);
3914 thr
->thread_fsm
->clean_up (thr
);
3917 if (ecs
->event_thread
!= NULL
)
3918 switch_to_thread (ecs
->event_thread
);
3922 /* Helper for all_uis_check_sync_execution_done that works on the
3926 check_curr_ui_sync_execution_done (void)
3928 struct ui
*ui
= current_ui
;
3930 if (ui
->prompt_state
== PROMPT_NEEDED
3932 && !gdb_in_secondary_prompt_p (ui
))
3934 target_terminal::ours ();
3935 gdb::observers::sync_execution_done
.notify ();
3936 ui_register_input_event_handler (ui
);
3943 all_uis_check_sync_execution_done (void)
3945 SWITCH_THRU_ALL_UIS ()
3947 check_curr_ui_sync_execution_done ();
3954 all_uis_on_sync_execution_starting (void)
3956 SWITCH_THRU_ALL_UIS ()
3958 if (current_ui
->prompt_state
== PROMPT_NEEDED
)
3959 async_disable_stdin ();
3963 /* Asynchronous version of wait_for_inferior. It is called by the
3964 event loop whenever a change of state is detected on the file
3965 descriptor corresponding to the target. It can be called more than
3966 once to complete a single execution command. In such cases we need
3967 to keep the state in a global variable ECSS. If it is the last time
3968 that this function is called for a single execution command, then
3969 report to the user that the inferior has stopped, and do the
3970 necessary cleanups. */
3973 fetch_inferior_event ()
3975 INFRUN_SCOPED_DEBUG_ENTER_EXIT
;
3977 struct execution_control_state ecss
;
3978 struct execution_control_state
*ecs
= &ecss
;
3981 memset (ecs
, 0, sizeof (*ecs
));
3983 /* Events are always processed with the main UI as current UI. This
3984 way, warnings, debug output, etc. are always consistently sent to
3985 the main console. */
3986 scoped_restore save_ui
= make_scoped_restore (¤t_ui
, main_ui
);
3988 /* Temporarily disable pagination. Otherwise, the user would be
3989 given an option to press 'q' to quit, which would cause an early
3990 exit and could leave GDB in a half-baked state. */
3991 scoped_restore save_pagination
3992 = make_scoped_restore (&pagination_enabled
, false);
3994 /* End up with readline processing input, if necessary. */
3996 SCOPE_EXIT
{ reinstall_readline_callback_handler_cleanup (); };
3998 /* We're handling a live event, so make sure we're doing live
3999 debugging. If we're looking at traceframes while the target is
4000 running, we're going to need to get back to that mode after
4001 handling the event. */
4002 gdb::optional
<scoped_restore_current_traceframe
> maybe_restore_traceframe
;
4005 maybe_restore_traceframe
.emplace ();
4006 set_current_traceframe (-1);
4009 /* The user/frontend should not notice a thread switch due to
4010 internal events. Make sure we revert to the user selected
4011 thread and frame after handling the event and running any
4012 breakpoint commands. */
4013 scoped_restore_current_thread restore_thread
;
4015 overlay_cache_invalid
= 1;
4016 /* Flush target cache before starting to handle each event. Target
4017 was running and cache could be stale. This is just a heuristic.
4018 Running threads may modify target memory, but we don't get any
4020 target_dcache_invalidate ();
4022 scoped_restore save_exec_dir
4023 = make_scoped_restore (&execution_direction
,
4024 target_execution_direction ());
4026 /* Allow targets to pause their resumed threads while we handle
4028 scoped_disable_commit_resumed
disable_commit_resumed ("handling event");
4030 if (!do_target_wait (ecs
, TARGET_WNOHANG
))
4032 infrun_debug_printf ("do_target_wait returned no event");
4033 disable_commit_resumed
.reset_and_commit ();
4037 gdb_assert (ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
);
4039 /* Switch to the target that generated the event, so we can do
4041 switch_to_target_no_thread (ecs
->target
);
4044 print_target_wait_results (minus_one_ptid
, ecs
->ptid
, &ecs
->ws
);
4046 /* If an error happens while handling the event, propagate GDB's
4047 knowledge of the executing state to the frontend/user running
4049 ptid_t finish_ptid
= !target_is_non_stop_p () ? minus_one_ptid
: ecs
->ptid
;
4050 scoped_finish_thread_state
finish_state (ecs
->target
, finish_ptid
);
4052 /* Get executed before scoped_restore_current_thread above to apply
4053 still for the thread which has thrown the exception. */
4054 auto defer_bpstat_clear
4055 = make_scope_exit (bpstat_clear_actions
);
4056 auto defer_delete_threads
4057 = make_scope_exit (delete_just_stopped_threads_infrun_breakpoints
);
4059 /* Now figure out what to do with the result of the result. */
4060 handle_inferior_event (ecs
);
4062 if (!ecs
->wait_some_more
)
4064 struct inferior
*inf
= find_inferior_ptid (ecs
->target
, ecs
->ptid
);
4065 bool should_stop
= true;
4066 struct thread_info
*thr
= ecs
->event_thread
;
4068 delete_just_stopped_threads_infrun_breakpoints ();
4072 struct thread_fsm
*thread_fsm
= thr
->thread_fsm
;
4074 if (thread_fsm
!= NULL
)
4075 should_stop
= thread_fsm
->should_stop (thr
);
4084 bool should_notify_stop
= true;
4087 clean_up_just_stopped_threads_fsms (ecs
);
4089 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
4090 should_notify_stop
= thr
->thread_fsm
->should_notify_stop ();
4092 if (should_notify_stop
)
4094 /* We may not find an inferior if this was a process exit. */
4095 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
4096 proceeded
= normal_stop ();
4101 inferior_event_handler (INF_EXEC_COMPLETE
);
4105 /* If we got a TARGET_WAITKIND_NO_RESUMED event, then the
4106 previously selected thread is gone. We have two
4107 choices - switch to no thread selected, or restore the
4108 previously selected thread (now exited). We chose the
4109 later, just because that's what GDB used to do. After
4110 this, "info threads" says "The current thread <Thread
4111 ID 2> has terminated." instead of "No thread
4115 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
4116 restore_thread
.dont_restore ();
4120 defer_delete_threads
.release ();
4121 defer_bpstat_clear
.release ();
4123 /* No error, don't finish the thread states yet. */
4124 finish_state
.release ();
4126 disable_commit_resumed
.reset_and_commit ();
4128 /* This scope is used to ensure that readline callbacks are
4129 reinstalled here. */
4132 /* If a UI was in sync execution mode, and now isn't, restore its
4133 prompt (a synchronous execution command has finished, and we're
4134 ready for input). */
4135 all_uis_check_sync_execution_done ();
4138 && exec_done_display_p
4139 && (inferior_ptid
== null_ptid
4140 || inferior_thread ()->state
!= THREAD_RUNNING
))
4141 printf_unfiltered (_("completed.\n"));
4147 set_step_info (thread_info
*tp
, struct frame_info
*frame
,
4148 struct symtab_and_line sal
)
4150 /* This can be removed once this function no longer implicitly relies on the
4151 inferior_ptid value. */
4152 gdb_assert (inferior_ptid
== tp
->ptid
);
4154 tp
->control
.step_frame_id
= get_frame_id (frame
);
4155 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
4157 tp
->current_symtab
= sal
.symtab
;
4158 tp
->current_line
= sal
.line
;
4161 /* Clear context switchable stepping state. */
4164 init_thread_stepping_state (struct thread_info
*tss
)
4166 tss
->stepped_breakpoint
= 0;
4167 tss
->stepping_over_breakpoint
= 0;
4168 tss
->stepping_over_watchpoint
= 0;
4169 tss
->step_after_step_resume_breakpoint
= 0;
4175 set_last_target_status (process_stratum_target
*target
, ptid_t ptid
,
4176 target_waitstatus status
)
4178 target_last_proc_target
= target
;
4179 target_last_wait_ptid
= ptid
;
4180 target_last_waitstatus
= status
;
4186 get_last_target_status (process_stratum_target
**target
, ptid_t
*ptid
,
4187 target_waitstatus
*status
)
4189 if (target
!= nullptr)
4190 *target
= target_last_proc_target
;
4191 if (ptid
!= nullptr)
4192 *ptid
= target_last_wait_ptid
;
4193 if (status
!= nullptr)
4194 *status
= target_last_waitstatus
;
4200 nullify_last_target_wait_ptid (void)
4202 target_last_proc_target
= nullptr;
4203 target_last_wait_ptid
= minus_one_ptid
;
4204 target_last_waitstatus
= {};
4207 /* Switch thread contexts. */
4210 context_switch (execution_control_state
*ecs
)
4212 if (ecs
->ptid
!= inferior_ptid
4213 && (inferior_ptid
== null_ptid
4214 || ecs
->event_thread
!= inferior_thread ()))
4216 infrun_debug_printf ("Switching context from %s to %s",
4217 target_pid_to_str (inferior_ptid
).c_str (),
4218 target_pid_to_str (ecs
->ptid
).c_str ());
4221 switch_to_thread (ecs
->event_thread
);
4224 /* If the target can't tell whether we've hit breakpoints
4225 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
4226 check whether that could have been caused by a breakpoint. If so,
4227 adjust the PC, per gdbarch_decr_pc_after_break. */
4230 adjust_pc_after_break (struct thread_info
*thread
,
4231 const target_waitstatus
*ws
)
4233 struct regcache
*regcache
;
4234 struct gdbarch
*gdbarch
;
4235 CORE_ADDR breakpoint_pc
, decr_pc
;
4237 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
4238 we aren't, just return.
4240 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
4241 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
4242 implemented by software breakpoints should be handled through the normal
4245 NOTE drow/2004-01-31: On some targets, breakpoints may generate
4246 different signals (SIGILL or SIGEMT for instance), but it is less
4247 clear where the PC is pointing afterwards. It may not match
4248 gdbarch_decr_pc_after_break. I don't know any specific target that
4249 generates these signals at breakpoints (the code has been in GDB since at
4250 least 1992) so I can not guess how to handle them here.
4252 In earlier versions of GDB, a target with
4253 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
4254 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
4255 target with both of these set in GDB history, and it seems unlikely to be
4256 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
4258 if (ws
->kind
!= TARGET_WAITKIND_STOPPED
)
4261 if (ws
->value
.sig
!= GDB_SIGNAL_TRAP
)
4264 /* In reverse execution, when a breakpoint is hit, the instruction
4265 under it has already been de-executed. The reported PC always
4266 points at the breakpoint address, so adjusting it further would
4267 be wrong. E.g., consider this case on a decr_pc_after_break == 1
4270 B1 0x08000000 : INSN1
4271 B2 0x08000001 : INSN2
4273 PC -> 0x08000003 : INSN4
4275 Say you're stopped at 0x08000003 as above. Reverse continuing
4276 from that point should hit B2 as below. Reading the PC when the
4277 SIGTRAP is reported should read 0x08000001 and INSN2 should have
4278 been de-executed already.
4280 B1 0x08000000 : INSN1
4281 B2 PC -> 0x08000001 : INSN2
4285 We can't apply the same logic as for forward execution, because
4286 we would wrongly adjust the PC to 0x08000000, since there's a
4287 breakpoint at PC - 1. We'd then report a hit on B1, although
4288 INSN1 hadn't been de-executed yet. Doing nothing is the correct
4290 if (execution_direction
== EXEC_REVERSE
)
4293 /* If the target can tell whether the thread hit a SW breakpoint,
4294 trust it. Targets that can tell also adjust the PC
4296 if (target_supports_stopped_by_sw_breakpoint ())
4299 /* Note that relying on whether a breakpoint is planted in memory to
4300 determine this can fail. E.g,. the breakpoint could have been
4301 removed since. Or the thread could have been told to step an
4302 instruction the size of a breakpoint instruction, and only
4303 _after_ was a breakpoint inserted at its address. */
4305 /* If this target does not decrement the PC after breakpoints, then
4306 we have nothing to do. */
4307 regcache
= get_thread_regcache (thread
);
4308 gdbarch
= regcache
->arch ();
4310 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
4314 const address_space
*aspace
= regcache
->aspace ();
4316 /* Find the location where (if we've hit a breakpoint) the
4317 breakpoint would be. */
4318 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
4320 /* If the target can't tell whether a software breakpoint triggered,
4321 fallback to figuring it out based on breakpoints we think were
4322 inserted in the target, and on whether the thread was stepped or
4325 /* Check whether there actually is a software breakpoint inserted at
4328 If in non-stop mode, a race condition is possible where we've
4329 removed a breakpoint, but stop events for that breakpoint were
4330 already queued and arrive later. To suppress those spurious
4331 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
4332 and retire them after a number of stop events are reported. Note
4333 this is an heuristic and can thus get confused. The real fix is
4334 to get the "stopped by SW BP and needs adjustment" info out of
4335 the target/kernel (and thus never reach here; see above). */
4336 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
4337 || (target_is_non_stop_p ()
4338 && moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
4340 gdb::optional
<scoped_restore_tmpl
<int>> restore_operation_disable
;
4342 if (record_full_is_used ())
4343 restore_operation_disable
.emplace
4344 (record_full_gdb_operation_disable_set ());
4346 /* When using hardware single-step, a SIGTRAP is reported for both
4347 a completed single-step and a software breakpoint. Need to
4348 differentiate between the two, as the latter needs adjusting
4349 but the former does not.
4351 The SIGTRAP can be due to a completed hardware single-step only if
4352 - we didn't insert software single-step breakpoints
4353 - this thread is currently being stepped
4355 If any of these events did not occur, we must have stopped due
4356 to hitting a software breakpoint, and have to back up to the
4359 As a special case, we could have hardware single-stepped a
4360 software breakpoint. In this case (prev_pc == breakpoint_pc),
4361 we also need to back up to the breakpoint address. */
4363 if (thread_has_single_step_breakpoints_set (thread
)
4364 || !currently_stepping (thread
)
4365 || (thread
->stepped_breakpoint
4366 && thread
->prev_pc
== breakpoint_pc
))
4367 regcache_write_pc (regcache
, breakpoint_pc
);
4372 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
4374 for (frame
= get_prev_frame (frame
);
4376 frame
= get_prev_frame (frame
))
4378 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
4381 if (get_frame_type (frame
) != INLINE_FRAME
)
4388 /* Look for an inline frame that is marked for skip.
4389 If PREV_FRAME is TRUE start at the previous frame,
4390 otherwise start at the current frame. Stop at the
4391 first non-inline frame, or at the frame where the
4395 inline_frame_is_marked_for_skip (bool prev_frame
, struct thread_info
*tp
)
4397 struct frame_info
*frame
= get_current_frame ();
4400 frame
= get_prev_frame (frame
);
4402 for (; frame
!= NULL
; frame
= get_prev_frame (frame
))
4404 const char *fn
= NULL
;
4405 symtab_and_line sal
;
4408 if (frame_id_eq (get_frame_id (frame
), tp
->control
.step_frame_id
))
4410 if (get_frame_type (frame
) != INLINE_FRAME
)
4413 sal
= find_frame_sal (frame
);
4414 sym
= get_frame_function (frame
);
4417 fn
= sym
->print_name ();
4420 && function_name_is_marked_for_skip (fn
, sal
))
4427 /* If the event thread has the stop requested flag set, pretend it
4428 stopped for a GDB_SIGNAL_0 (i.e., as if it stopped due to
4432 handle_stop_requested (struct execution_control_state
*ecs
)
4434 if (ecs
->event_thread
->stop_requested
)
4436 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
4437 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
4438 handle_signal_stop (ecs
);
4444 /* Auxiliary function that handles syscall entry/return events.
4445 It returns true if the inferior should keep going (and GDB
4446 should ignore the event), or false if the event deserves to be
4450 handle_syscall_event (struct execution_control_state
*ecs
)
4452 struct regcache
*regcache
;
4455 context_switch (ecs
);
4457 regcache
= get_thread_regcache (ecs
->event_thread
);
4458 syscall_number
= ecs
->ws
.value
.syscall_number
;
4459 ecs
->event_thread
->set_stop_pc (regcache_read_pc (regcache
));
4461 if (catch_syscall_enabled () > 0
4462 && catching_syscall_number (syscall_number
))
4464 infrun_debug_printf ("syscall number=%d", syscall_number
);
4466 ecs
->event_thread
->control
.stop_bpstat
4467 = bpstat_stop_status (regcache
->aspace (),
4468 ecs
->event_thread
->stop_pc (),
4469 ecs
->event_thread
, &ecs
->ws
);
4471 if (handle_stop_requested (ecs
))
4474 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4476 /* Catchpoint hit. */
4481 if (handle_stop_requested (ecs
))
4484 /* If no catchpoint triggered for this, then keep going. */
4490 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4493 fill_in_stop_func (struct gdbarch
*gdbarch
,
4494 struct execution_control_state
*ecs
)
4496 if (!ecs
->stop_func_filled_in
)
4499 const general_symbol_info
*gsi
;
4501 /* Don't care about return value; stop_func_start and stop_func_name
4502 will both be 0 if it doesn't work. */
4503 find_pc_partial_function_sym (ecs
->event_thread
->stop_pc (),
4505 &ecs
->stop_func_start
,
4506 &ecs
->stop_func_end
,
4508 ecs
->stop_func_name
= gsi
== nullptr ? nullptr : gsi
->print_name ();
4510 /* The call to find_pc_partial_function, above, will set
4511 stop_func_start and stop_func_end to the start and end
4512 of the range containing the stop pc. If this range
4513 contains the entry pc for the block (which is always the
4514 case for contiguous blocks), advance stop_func_start past
4515 the function's start offset and entrypoint. Note that
4516 stop_func_start is NOT advanced when in a range of a
4517 non-contiguous block that does not contain the entry pc. */
4518 if (block
!= nullptr
4519 && ecs
->stop_func_start
<= BLOCK_ENTRY_PC (block
)
4520 && BLOCK_ENTRY_PC (block
) < ecs
->stop_func_end
)
4522 ecs
->stop_func_start
4523 += gdbarch_deprecated_function_start_offset (gdbarch
);
4525 if (gdbarch_skip_entrypoint_p (gdbarch
))
4526 ecs
->stop_func_start
4527 = gdbarch_skip_entrypoint (gdbarch
, ecs
->stop_func_start
);
4530 ecs
->stop_func_filled_in
= 1;
4535 /* Return the STOP_SOON field of the inferior pointed at by ECS. */
4537 static enum stop_kind
4538 get_inferior_stop_soon (execution_control_state
*ecs
)
4540 struct inferior
*inf
= find_inferior_ptid (ecs
->target
, ecs
->ptid
);
4542 gdb_assert (inf
!= NULL
);
4543 return inf
->control
.stop_soon
;
4546 /* Poll for one event out of the current target. Store the resulting
4547 waitstatus in WS, and return the event ptid. Does not block. */
4550 poll_one_curr_target (struct target_waitstatus
*ws
)
4554 overlay_cache_invalid
= 1;
4556 /* Flush target cache before starting to handle each event.
4557 Target was running and cache could be stale. This is just a
4558 heuristic. Running threads may modify target memory, but we
4559 don't get any event. */
4560 target_dcache_invalidate ();
4562 if (deprecated_target_wait_hook
)
4563 event_ptid
= deprecated_target_wait_hook (minus_one_ptid
, ws
, TARGET_WNOHANG
);
4565 event_ptid
= target_wait (minus_one_ptid
, ws
, TARGET_WNOHANG
);
4568 print_target_wait_results (minus_one_ptid
, event_ptid
, ws
);
4573 /* Wait for one event out of any target. */
4575 static wait_one_event
4580 for (inferior
*inf
: all_inferiors ())
4582 process_stratum_target
*target
= inf
->process_target ();
4584 || !target
->is_async_p ()
4585 || !target
->threads_executing
)
4588 switch_to_inferior_no_thread (inf
);
4590 wait_one_event event
;
4591 event
.target
= target
;
4592 event
.ptid
= poll_one_curr_target (&event
.ws
);
4594 if (event
.ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4596 /* If nothing is resumed, remove the target from the
4600 else if (event
.ws
.kind
!= TARGET_WAITKIND_IGNORE
)
4604 /* Block waiting for some event. */
4611 for (inferior
*inf
: all_inferiors ())
4613 process_stratum_target
*target
= inf
->process_target ();
4615 || !target
->is_async_p ()
4616 || !target
->threads_executing
)
4619 int fd
= target
->async_wait_fd ();
4620 FD_SET (fd
, &readfds
);
4627 /* No waitable targets left. All must be stopped. */
4628 return {NULL
, minus_one_ptid
, {TARGET_WAITKIND_NO_RESUMED
}};
4633 int numfds
= interruptible_select (nfds
, &readfds
, 0, NULL
, 0);
4639 perror_with_name ("interruptible_select");
4644 /* Save the thread's event and stop reason to process it later. */
4647 save_waitstatus (struct thread_info
*tp
, const target_waitstatus
*ws
)
4649 infrun_debug_printf ("saving status %s for %s",
4650 target_waitstatus_to_string (ws
).c_str (),
4651 tp
->ptid
.to_string ().c_str ());
4653 /* Record for later. */
4654 tp
->set_pending_waitstatus (*ws
);
4656 if (ws
->kind
== TARGET_WAITKIND_STOPPED
4657 && ws
->value
.sig
== GDB_SIGNAL_TRAP
)
4659 struct regcache
*regcache
= get_thread_regcache (tp
);
4660 const address_space
*aspace
= regcache
->aspace ();
4661 CORE_ADDR pc
= regcache_read_pc (regcache
);
4663 adjust_pc_after_break (tp
, &tp
->pending_waitstatus ());
4665 scoped_restore_current_thread restore_thread
;
4666 switch_to_thread (tp
);
4668 if (target_stopped_by_watchpoint ())
4669 tp
->set_stop_reason (TARGET_STOPPED_BY_WATCHPOINT
);
4670 else if (target_supports_stopped_by_sw_breakpoint ()
4671 && target_stopped_by_sw_breakpoint ())
4672 tp
->set_stop_reason (TARGET_STOPPED_BY_SW_BREAKPOINT
);
4673 else if (target_supports_stopped_by_hw_breakpoint ()
4674 && target_stopped_by_hw_breakpoint ())
4675 tp
->set_stop_reason (TARGET_STOPPED_BY_HW_BREAKPOINT
);
4676 else if (!target_supports_stopped_by_hw_breakpoint ()
4677 && hardware_breakpoint_inserted_here_p (aspace
, pc
))
4678 tp
->set_stop_reason (TARGET_STOPPED_BY_HW_BREAKPOINT
);
4679 else if (!target_supports_stopped_by_sw_breakpoint ()
4680 && software_breakpoint_inserted_here_p (aspace
, pc
))
4681 tp
->set_stop_reason (TARGET_STOPPED_BY_SW_BREAKPOINT
);
4682 else if (!thread_has_single_step_breakpoints_set (tp
)
4683 && currently_stepping (tp
))
4684 tp
->set_stop_reason (TARGET_STOPPED_BY_SINGLE_STEP
);
4688 /* Mark the non-executing threads accordingly. In all-stop, all
4689 threads of all processes are stopped when we get any event
4690 reported. In non-stop mode, only the event thread stops. */
4693 mark_non_executing_threads (process_stratum_target
*target
,
4695 struct target_waitstatus ws
)
4699 if (!target_is_non_stop_p ())
4700 mark_ptid
= minus_one_ptid
;
4701 else if (ws
.kind
== TARGET_WAITKIND_SIGNALLED
4702 || ws
.kind
== TARGET_WAITKIND_EXITED
)
4704 /* If we're handling a process exit in non-stop mode, even
4705 though threads haven't been deleted yet, one would think
4706 that there is nothing to do, as threads of the dead process
4707 will be soon deleted, and threads of any other process were
4708 left running. However, on some targets, threads survive a
4709 process exit event. E.g., for the "checkpoint" command,
4710 when the current checkpoint/fork exits, linux-fork.c
4711 automatically switches to another fork from within
4712 target_mourn_inferior, by associating the same
4713 inferior/thread to another fork. We haven't mourned yet at
4714 this point, but we must mark any threads left in the
4715 process as not-executing so that finish_thread_state marks
4716 them stopped (in the user's perspective) if/when we present
4717 the stop to the user. */
4718 mark_ptid
= ptid_t (event_ptid
.pid ());
4721 mark_ptid
= event_ptid
;
4723 set_executing (target
, mark_ptid
, false);
4725 /* Likewise the resumed flag. */
4726 set_resumed (target
, mark_ptid
, false);
4729 /* Handle one event after stopping threads. If the eventing thread
4730 reports back any interesting event, we leave it pending. If the
4731 eventing thread was in the middle of a displaced step, we
4732 cancel/finish it, and unless the thread's inferior is being
4733 detached, put the thread back in the step-over chain. Returns true
4734 if there are no resumed threads left in the target (thus there's no
4735 point in waiting further), false otherwise. */
4738 handle_one (const wait_one_event
&event
)
4741 ("%s %s", target_waitstatus_to_string (&event
.ws
).c_str (),
4742 target_pid_to_str (event
.ptid
).c_str ());
4744 if (event
.ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4746 /* All resumed threads exited. */
4749 else if (event
.ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
4750 || event
.ws
.kind
== TARGET_WAITKIND_EXITED
4751 || event
.ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
4753 /* One thread/process exited/signalled. */
4755 thread_info
*t
= nullptr;
4757 /* The target may have reported just a pid. If so, try
4758 the first non-exited thread. */
4759 if (event
.ptid
.is_pid ())
4761 int pid
= event
.ptid
.pid ();
4762 inferior
*inf
= find_inferior_pid (event
.target
, pid
);
4763 for (thread_info
*tp
: inf
->non_exited_threads ())
4769 /* If there is no available thread, the event would
4770 have to be appended to a per-inferior event list,
4771 which does not exist (and if it did, we'd have
4772 to adjust run control command to be able to
4773 resume such an inferior). We assert here instead
4774 of going into an infinite loop. */
4775 gdb_assert (t
!= nullptr);
4778 ("using %s", target_pid_to_str (t
->ptid
).c_str ());
4782 t
= find_thread_ptid (event
.target
, event
.ptid
);
4783 /* Check if this is the first time we see this thread.
4784 Don't bother adding if it individually exited. */
4786 && event
.ws
.kind
!= TARGET_WAITKIND_THREAD_EXITED
)
4787 t
= add_thread (event
.target
, event
.ptid
);
4792 /* Set the threads as non-executing to avoid
4793 another stop attempt on them. */
4794 switch_to_thread_no_regs (t
);
4795 mark_non_executing_threads (event
.target
, event
.ptid
,
4797 save_waitstatus (t
, &event
.ws
);
4798 t
->stop_requested
= false;
4803 thread_info
*t
= find_thread_ptid (event
.target
, event
.ptid
);
4805 t
= add_thread (event
.target
, event
.ptid
);
4807 t
->stop_requested
= 0;
4808 t
->set_executing (false);
4809 t
->set_resumed (false);
4810 t
->control
.may_range_step
= 0;
4812 /* This may be the first time we see the inferior report
4814 inferior
*inf
= find_inferior_ptid (event
.target
, event
.ptid
);
4815 if (inf
->needs_setup
)
4817 switch_to_thread_no_regs (t
);
4821 if (event
.ws
.kind
== TARGET_WAITKIND_STOPPED
4822 && event
.ws
.value
.sig
== GDB_SIGNAL_0
)
4824 /* We caught the event that we intended to catch, so
4825 there's no event to save as pending. */
4827 if (displaced_step_finish (t
, GDB_SIGNAL_0
)
4828 == DISPLACED_STEP_FINISH_STATUS_NOT_EXECUTED
)
4830 /* Add it back to the step-over queue. */
4832 ("displaced-step of %s canceled",
4833 target_pid_to_str (t
->ptid
).c_str ());
4835 t
->control
.trap_expected
= 0;
4836 if (!t
->inf
->detaching
)
4837 global_thread_step_over_chain_enqueue (t
);
4842 enum gdb_signal sig
;
4843 struct regcache
*regcache
;
4846 ("target_wait %s, saving status for %s",
4847 target_waitstatus_to_string (&event
.ws
).c_str (),
4848 t
->ptid
.to_string ().c_str ());
4850 /* Record for later. */
4851 save_waitstatus (t
, &event
.ws
);
4853 sig
= (event
.ws
.kind
== TARGET_WAITKIND_STOPPED
4854 ? event
.ws
.value
.sig
: GDB_SIGNAL_0
);
4856 if (displaced_step_finish (t
, sig
)
4857 == DISPLACED_STEP_FINISH_STATUS_NOT_EXECUTED
)
4859 /* Add it back to the step-over queue. */
4860 t
->control
.trap_expected
= 0;
4861 if (!t
->inf
->detaching
)
4862 global_thread_step_over_chain_enqueue (t
);
4865 regcache
= get_thread_regcache (t
);
4866 t
->set_stop_pc (regcache_read_pc (regcache
));
4868 infrun_debug_printf ("saved stop_pc=%s for %s "
4869 "(currently_stepping=%d)",
4870 paddress (target_gdbarch (), t
->stop_pc ()),
4871 target_pid_to_str (t
->ptid
).c_str (),
4872 currently_stepping (t
));
4882 stop_all_threads (void)
4884 /* We may need multiple passes to discover all threads. */
4888 gdb_assert (exists_non_stop_target ());
4890 infrun_debug_printf ("starting");
4892 scoped_restore_current_thread restore_thread
;
4894 /* Enable thread events of all targets. */
4895 for (auto *target
: all_non_exited_process_targets ())
4897 switch_to_target_no_thread (target
);
4898 target_thread_events (true);
4903 /* Disable thread events of all targets. */
4904 for (auto *target
: all_non_exited_process_targets ())
4906 switch_to_target_no_thread (target
);
4907 target_thread_events (false);
4910 /* Use debug_prefixed_printf directly to get a meaningful function
4913 debug_prefixed_printf ("infrun", "stop_all_threads", "done");
4916 /* Request threads to stop, and then wait for the stops. Because
4917 threads we already know about can spawn more threads while we're
4918 trying to stop them, and we only learn about new threads when we
4919 update the thread list, do this in a loop, and keep iterating
4920 until two passes find no threads that need to be stopped. */
4921 for (pass
= 0; pass
< 2; pass
++, iterations
++)
4923 infrun_debug_printf ("pass=%d, iterations=%d", pass
, iterations
);
4926 int waits_needed
= 0;
4928 for (auto *target
: all_non_exited_process_targets ())
4930 switch_to_target_no_thread (target
);
4931 update_thread_list ();
4934 /* Go through all threads looking for threads that we need
4935 to tell the target to stop. */
4936 for (thread_info
*t
: all_non_exited_threads ())
4938 /* For a single-target setting with an all-stop target,
4939 we would not even arrive here. For a multi-target
4940 setting, until GDB is able to handle a mixture of
4941 all-stop and non-stop targets, simply skip all-stop
4942 targets' threads. This should be fine due to the
4943 protection of 'check_multi_target_resumption'. */
4945 switch_to_thread_no_regs (t
);
4946 if (!target_is_non_stop_p ())
4949 if (t
->executing ())
4951 /* If already stopping, don't request a stop again.
4952 We just haven't seen the notification yet. */
4953 if (!t
->stop_requested
)
4955 infrun_debug_printf (" %s executing, need stop",
4956 target_pid_to_str (t
->ptid
).c_str ());
4957 target_stop (t
->ptid
);
4958 t
->stop_requested
= 1;
4962 infrun_debug_printf (" %s executing, already stopping",
4963 target_pid_to_str (t
->ptid
).c_str ());
4966 if (t
->stop_requested
)
4971 infrun_debug_printf (" %s not executing",
4972 target_pid_to_str (t
->ptid
).c_str ());
4974 /* The thread may be not executing, but still be
4975 resumed with a pending status to process. */
4976 t
->set_resumed (false);
4980 if (waits_needed
== 0)
4983 /* If we find new threads on the second iteration, restart
4984 over. We want to see two iterations in a row with all
4989 for (int i
= 0; i
< waits_needed
; i
++)
4991 wait_one_event event
= wait_one ();
4992 if (handle_one (event
))
4999 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
5002 handle_no_resumed (struct execution_control_state
*ecs
)
5004 if (target_can_async_p ())
5006 bool any_sync
= false;
5008 for (ui
*ui
: all_uis ())
5010 if (ui
->prompt_state
== PROMPT_BLOCKED
)
5018 /* There were no unwaited-for children left in the target, but,
5019 we're not synchronously waiting for events either. Just
5022 infrun_debug_printf ("TARGET_WAITKIND_NO_RESUMED (ignoring: bg)");
5023 prepare_to_wait (ecs
);
5028 /* Otherwise, if we were running a synchronous execution command, we
5029 may need to cancel it and give the user back the terminal.
5031 In non-stop mode, the target can't tell whether we've already
5032 consumed previous stop events, so it can end up sending us a
5033 no-resumed event like so:
5035 #0 - thread 1 is left stopped
5037 #1 - thread 2 is resumed and hits breakpoint
5038 -> TARGET_WAITKIND_STOPPED
5040 #2 - thread 3 is resumed and exits
5041 this is the last resumed thread, so
5042 -> TARGET_WAITKIND_NO_RESUMED
5044 #3 - gdb processes stop for thread 2 and decides to re-resume
5047 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
5048 thread 2 is now resumed, so the event should be ignored.
5050 IOW, if the stop for thread 2 doesn't end a foreground command,
5051 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
5052 event. But it could be that the event meant that thread 2 itself
5053 (or whatever other thread was the last resumed thread) exited.
5055 To address this we refresh the thread list and check whether we
5056 have resumed threads _now_. In the example above, this removes
5057 thread 3 from the thread list. If thread 2 was re-resumed, we
5058 ignore this event. If we find no thread resumed, then we cancel
5059 the synchronous command and show "no unwaited-for " to the
5062 inferior
*curr_inf
= current_inferior ();
5064 scoped_restore_current_thread restore_thread
;
5066 for (auto *target
: all_non_exited_process_targets ())
5068 switch_to_target_no_thread (target
);
5069 update_thread_list ();
5074 - the current target has no thread executing, and
5075 - the current inferior is native, and
5076 - the current inferior is the one which has the terminal, and
5079 then a Ctrl-C from this point on would remain stuck in the
5080 kernel, until a thread resumes and dequeues it. That would
5081 result in the GDB CLI not reacting to Ctrl-C, not able to
5082 interrupt the program. To address this, if the current inferior
5083 no longer has any thread executing, we give the terminal to some
5084 other inferior that has at least one thread executing. */
5085 bool swap_terminal
= true;
5087 /* Whether to ignore this TARGET_WAITKIND_NO_RESUMED event, or
5088 whether to report it to the user. */
5089 bool ignore_event
= false;
5091 for (thread_info
*thread
: all_non_exited_threads ())
5093 if (swap_terminal
&& thread
->executing ())
5095 if (thread
->inf
!= curr_inf
)
5097 target_terminal::ours ();
5099 switch_to_thread (thread
);
5100 target_terminal::inferior ();
5102 swap_terminal
= false;
5106 && (thread
->executing () || thread
->has_pending_waitstatus ()))
5108 /* Either there were no unwaited-for children left in the
5109 target at some point, but there are now, or some target
5110 other than the eventing one has unwaited-for children
5111 left. Just ignore. */
5112 infrun_debug_printf ("TARGET_WAITKIND_NO_RESUMED "
5113 "(ignoring: found resumed)");
5115 ignore_event
= true;
5118 if (ignore_event
&& !swap_terminal
)
5124 switch_to_inferior_no_thread (curr_inf
);
5125 prepare_to_wait (ecs
);
5129 /* Go ahead and report the event. */
5133 /* Given an execution control state that has been freshly filled in by
5134 an event from the inferior, figure out what it means and take
5137 The alternatives are:
5139 1) stop_waiting and return; to really stop and return to the
5142 2) keep_going and return; to wait for the next event (set
5143 ecs->event_thread->stepping_over_breakpoint to 1 to single step
5147 handle_inferior_event (struct execution_control_state
*ecs
)
5149 /* Make sure that all temporary struct value objects that were
5150 created during the handling of the event get deleted at the
5152 scoped_value_mark free_values
;
5154 infrun_debug_printf ("%s", target_waitstatus_to_string (&ecs
->ws
).c_str ());
5156 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
5158 /* We had an event in the inferior, but we are not interested in
5159 handling it at this level. The lower layers have already
5160 done what needs to be done, if anything.
5162 One of the possible circumstances for this is when the
5163 inferior produces output for the console. The inferior has
5164 not stopped, and we are ignoring the event. Another possible
5165 circumstance is any event which the lower level knows will be
5166 reported multiple times without an intervening resume. */
5167 prepare_to_wait (ecs
);
5171 if (ecs
->ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
)
5173 prepare_to_wait (ecs
);
5177 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
5178 && handle_no_resumed (ecs
))
5181 /* Cache the last target/ptid/waitstatus. */
5182 set_last_target_status (ecs
->target
, ecs
->ptid
, ecs
->ws
);
5184 /* Always clear state belonging to the previous time we stopped. */
5185 stop_stack_dummy
= STOP_NONE
;
5187 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
5189 /* No unwaited-for children left. IOW, all resumed children
5191 stop_print_frame
= false;
5196 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
5197 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
5199 ecs
->event_thread
= find_thread_ptid (ecs
->target
, ecs
->ptid
);
5200 /* If it's a new thread, add it to the thread database. */
5201 if (ecs
->event_thread
== NULL
)
5202 ecs
->event_thread
= add_thread (ecs
->target
, ecs
->ptid
);
5204 /* Disable range stepping. If the next step request could use a
5205 range, this will be end up re-enabled then. */
5206 ecs
->event_thread
->control
.may_range_step
= 0;
5209 /* Dependent on valid ECS->EVENT_THREAD. */
5210 adjust_pc_after_break (ecs
->event_thread
, &ecs
->ws
);
5212 /* Dependent on the current PC value modified by adjust_pc_after_break. */
5213 reinit_frame_cache ();
5215 breakpoint_retire_moribund ();
5217 /* First, distinguish signals caused by the debugger from signals
5218 that have to do with the program's own actions. Note that
5219 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
5220 on the operating system version. Here we detect when a SIGILL or
5221 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
5222 something similar for SIGSEGV, since a SIGSEGV will be generated
5223 when we're trying to execute a breakpoint instruction on a
5224 non-executable stack. This happens for call dummy breakpoints
5225 for architectures like SPARC that place call dummies on the
5227 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
5228 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
5229 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
5230 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
5232 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
5234 if (breakpoint_inserted_here_p (regcache
->aspace (),
5235 regcache_read_pc (regcache
)))
5237 infrun_debug_printf ("Treating signal as SIGTRAP");
5238 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
5242 mark_non_executing_threads (ecs
->target
, ecs
->ptid
, ecs
->ws
);
5244 switch (ecs
->ws
.kind
)
5246 case TARGET_WAITKIND_LOADED
:
5248 context_switch (ecs
);
5249 /* Ignore gracefully during startup of the inferior, as it might
5250 be the shell which has just loaded some objects, otherwise
5251 add the symbols for the newly loaded objects. Also ignore at
5252 the beginning of an attach or remote session; we will query
5253 the full list of libraries once the connection is
5256 stop_kind stop_soon
= get_inferior_stop_soon (ecs
);
5257 if (stop_soon
== NO_STOP_QUIETLY
)
5259 struct regcache
*regcache
;
5261 regcache
= get_thread_regcache (ecs
->event_thread
);
5263 handle_solib_event ();
5265 ecs
->event_thread
->control
.stop_bpstat
5266 = bpstat_stop_status (regcache
->aspace (),
5267 ecs
->event_thread
->stop_pc (),
5268 ecs
->event_thread
, &ecs
->ws
);
5270 if (handle_stop_requested (ecs
))
5273 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5275 /* A catchpoint triggered. */
5276 process_event_stop_test (ecs
);
5280 /* If requested, stop when the dynamic linker notifies
5281 gdb of events. This allows the user to get control
5282 and place breakpoints in initializer routines for
5283 dynamically loaded objects (among other things). */
5284 ecs
->event_thread
->set_stop_signal (GDB_SIGNAL_0
);
5285 if (stop_on_solib_events
)
5287 /* Make sure we print "Stopped due to solib-event" in
5289 stop_print_frame
= true;
5296 /* If we are skipping through a shell, or through shared library
5297 loading that we aren't interested in, resume the program. If
5298 we're running the program normally, also resume. */
5299 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
5301 /* Loading of shared libraries might have changed breakpoint
5302 addresses. Make sure new breakpoints are inserted. */
5303 if (stop_soon
== NO_STOP_QUIETLY
)
5304 insert_breakpoints ();
5305 resume (GDB_SIGNAL_0
);
5306 prepare_to_wait (ecs
);
5310 /* But stop if we're attaching or setting up a remote
5312 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5313 || stop_soon
== STOP_QUIETLY_REMOTE
)
5315 infrun_debug_printf ("quietly stopped");
5320 internal_error (__FILE__
, __LINE__
,
5321 _("unhandled stop_soon: %d"), (int) stop_soon
);
5324 case TARGET_WAITKIND_SPURIOUS
:
5325 if (handle_stop_requested (ecs
))
5327 context_switch (ecs
);
5328 resume (GDB_SIGNAL_0
);
5329 prepare_to_wait (ecs
);
5332 case TARGET_WAITKIND_THREAD_CREATED
:
5333 if (handle_stop_requested (ecs
))
5335 context_switch (ecs
);
5336 if (!switch_back_to_stepped_thread (ecs
))
5340 case TARGET_WAITKIND_EXITED
:
5341 case TARGET_WAITKIND_SIGNALLED
:
5343 /* Depending on the system, ecs->ptid may point to a thread or
5344 to a process. On some targets, target_mourn_inferior may
5345 need to have access to the just-exited thread. That is the
5346 case of GNU/Linux's "checkpoint" support, for example.
5347 Call the switch_to_xxx routine as appropriate. */
5348 thread_info
*thr
= find_thread_ptid (ecs
->target
, ecs
->ptid
);
5350 switch_to_thread (thr
);
5353 inferior
*inf
= find_inferior_ptid (ecs
->target
, ecs
->ptid
);
5354 switch_to_inferior_no_thread (inf
);
5357 handle_vfork_child_exec_or_exit (0);
5358 target_terminal::ours (); /* Must do this before mourn anyway. */
5360 /* Clearing any previous state of convenience variables. */
5361 clear_exit_convenience_vars ();
5363 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5365 /* Record the exit code in the convenience variable $_exitcode, so
5366 that the user can inspect this again later. */
5367 set_internalvar_integer (lookup_internalvar ("_exitcode"),
5368 (LONGEST
) ecs
->ws
.value
.integer
);
5370 /* Also record this in the inferior itself. */
5371 current_inferior ()->has_exit_code
= 1;
5372 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
5374 /* Support the --return-child-result option. */
5375 return_child_result_value
= ecs
->ws
.value
.integer
;
5377 gdb::observers::exited
.notify (ecs
->ws
.value
.integer
);
5381 struct gdbarch
*gdbarch
= current_inferior ()->gdbarch
;
5383 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
5385 /* Set the value of the internal variable $_exitsignal,
5386 which holds the signal uncaught by the inferior. */
5387 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
5388 gdbarch_gdb_signal_to_target (gdbarch
,
5389 ecs
->ws
.value
.sig
));
5393 /* We don't have access to the target's method used for
5394 converting between signal numbers (GDB's internal
5395 representation <-> target's representation).
5396 Therefore, we cannot do a good job at displaying this
5397 information to the user. It's better to just warn
5398 her about it (if infrun debugging is enabled), and
5400 infrun_debug_printf ("Cannot fill $_exitsignal with the correct "
5404 gdb::observers::signal_exited
.notify (ecs
->ws
.value
.sig
);
5407 gdb_flush (gdb_stdout
);
5408 target_mourn_inferior (inferior_ptid
);
5409 stop_print_frame
= false;
5413 case TARGET_WAITKIND_FORKED
:
5414 case TARGET_WAITKIND_VFORKED
:
5415 /* Check whether the inferior is displaced stepping. */
5417 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
5418 struct gdbarch
*gdbarch
= regcache
->arch ();
5419 inferior
*parent_inf
= find_inferior_ptid (ecs
->target
, ecs
->ptid
);
5421 /* If this is a fork (child gets its own address space copy)
5422 and some displaced step buffers were in use at the time of
5423 the fork, restore the displaced step buffer bytes in the
5426 Architectures which support displaced stepping and fork
5427 events must supply an implementation of
5428 gdbarch_displaced_step_restore_all_in_ptid. This is not
5429 enforced during gdbarch validation to support architectures
5430 which support displaced stepping but not forks. */
5431 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
5432 && gdbarch_supports_displaced_stepping (gdbarch
))
5433 gdbarch_displaced_step_restore_all_in_ptid
5434 (gdbarch
, parent_inf
, ecs
->ws
.value
.related_pid
);
5436 /* If displaced stepping is supported, and thread ecs->ptid is
5437 displaced stepping. */
5438 if (displaced_step_in_progress_thread (ecs
->event_thread
))
5440 struct regcache
*child_regcache
;
5441 CORE_ADDR parent_pc
;
5443 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
5444 indicating that the displaced stepping of syscall instruction
5445 has been done. Perform cleanup for parent process here. Note
5446 that this operation also cleans up the child process for vfork,
5447 because their pages are shared. */
5448 displaced_step_finish (ecs
->event_thread
, GDB_SIGNAL_TRAP
);
5449 /* Start a new step-over in another thread if there's one
5453 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
5454 the child's PC is also within the scratchpad. Set the child's PC
5455 to the parent's PC value, which has already been fixed up.
5456 FIXME: we use the parent's aspace here, although we're touching
5457 the child, because the child hasn't been added to the inferior
5458 list yet at this point. */
5461 = get_thread_arch_aspace_regcache (parent_inf
->process_target (),
5462 ecs
->ws
.value
.related_pid
,
5464 parent_inf
->aspace
);
5465 /* Read PC value of parent process. */
5466 parent_pc
= regcache_read_pc (regcache
);
5468 displaced_debug_printf ("write child pc from %s to %s",
5470 regcache_read_pc (child_regcache
)),
5471 paddress (gdbarch
, parent_pc
));
5473 regcache_write_pc (child_regcache
, parent_pc
);
5477 context_switch (ecs
);
5479 /* Immediately detach breakpoints from the child before there's
5480 any chance of letting the user delete breakpoints from the
5481 breakpoint lists. If we don't do this early, it's easy to
5482 leave left over traps in the child, vis: "break foo; catch
5483 fork; c; <fork>; del; c; <child calls foo>". We only follow
5484 the fork on the last `continue', and by that time the
5485 breakpoint at "foo" is long gone from the breakpoint table.
5486 If we vforked, then we don't need to unpatch here, since both
5487 parent and child are sharing the same memory pages; we'll
5488 need to unpatch at follow/detach time instead to be certain
5489 that new breakpoints added between catchpoint hit time and
5490 vfork follow are detached. */
5491 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
5493 /* This won't actually modify the breakpoint list, but will
5494 physically remove the breakpoints from the child. */
5495 detach_breakpoints (ecs
->ws
.value
.related_pid
);
5498 delete_just_stopped_threads_single_step_breakpoints ();
5500 /* In case the event is caught by a catchpoint, remember that
5501 the event is to be followed at the next resume of the thread,
5502 and not immediately. */
5503 ecs
->event_thread
->pending_follow
= ecs
->ws
;
5505 ecs
->event_thread
->set_stop_pc
5506 (regcache_read_pc (get_thread_regcache (ecs
->event_thread
)));
5508 ecs
->event_thread
->control
.stop_bpstat
5509 = bpstat_stop_status (get_current_regcache ()->aspace (),
5510 ecs
->event_thread
->stop_pc (),
5511 ecs
->event_thread
, &ecs
->ws
);
5513 if (handle_stop_requested (ecs
))
5516 /* If no catchpoint triggered for this, then keep going. Note
5517 that we're interested in knowing the bpstat actually causes a
5518 stop, not just if it may explain the signal. Software
5519 watchpoints, for example, always appear in the bpstat. */
5520 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5523 = (follow_fork_mode_string
== follow_fork_mode_child
);
5525 ecs
->event_thread
->set_stop_signal (GDB_SIGNAL_0
);
5527 process_stratum_target
*targ
5528 = ecs
->event_thread
->inf
->process_target ();
5530 bool should_resume
= follow_fork ();
5532 /* Note that one of these may be an invalid pointer,
5533 depending on detach_fork. */
5534 thread_info
*parent
= ecs
->event_thread
;
5536 = find_thread_ptid (targ
, ecs
->ws
.value
.related_pid
);
5538 /* At this point, the parent is marked running, and the
5539 child is marked stopped. */
5541 /* If not resuming the parent, mark it stopped. */
5542 if (follow_child
&& !detach_fork
&& !non_stop
&& !sched_multi
)
5543 parent
->set_running (false);
5545 /* If resuming the child, mark it running. */
5546 if (follow_child
|| (!detach_fork
&& (non_stop
|| sched_multi
)))
5547 child
->set_running (true);
5549 /* In non-stop mode, also resume the other branch. */
5550 if (!detach_fork
&& (non_stop
5551 || (sched_multi
&& target_is_non_stop_p ())))
5554 switch_to_thread (parent
);
5556 switch_to_thread (child
);
5558 ecs
->event_thread
= inferior_thread ();
5559 ecs
->ptid
= inferior_ptid
;
5564 switch_to_thread (child
);
5566 switch_to_thread (parent
);
5568 ecs
->event_thread
= inferior_thread ();
5569 ecs
->ptid
= inferior_ptid
;
5577 process_event_stop_test (ecs
);
5580 case TARGET_WAITKIND_VFORK_DONE
:
5581 /* Done with the shared memory region. Re-insert breakpoints in
5582 the parent, and keep going. */
5584 context_switch (ecs
);
5586 current_inferior ()->waiting_for_vfork_done
= 0;
5587 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
5589 if (handle_stop_requested (ecs
))
5592 /* This also takes care of reinserting breakpoints in the
5593 previously locked inferior. */
5597 case TARGET_WAITKIND_EXECD
:
5599 /* Note we can't read registers yet (the stop_pc), because we
5600 don't yet know the inferior's post-exec architecture.
5601 'stop_pc' is explicitly read below instead. */
5602 switch_to_thread_no_regs (ecs
->event_thread
);
5604 /* Do whatever is necessary to the parent branch of the vfork. */
5605 handle_vfork_child_exec_or_exit (1);
5607 /* This causes the eventpoints and symbol table to be reset.
5608 Must do this now, before trying to determine whether to
5610 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
5612 /* In follow_exec we may have deleted the original thread and
5613 created a new one. Make sure that the event thread is the
5614 execd thread for that case (this is a nop otherwise). */
5615 ecs
->event_thread
= inferior_thread ();
5617 ecs
->event_thread
->set_stop_pc
5618 (regcache_read_pc (get_thread_regcache (ecs
->event_thread
)));
5620 ecs
->event_thread
->control
.stop_bpstat
5621 = bpstat_stop_status (get_current_regcache ()->aspace (),
5622 ecs
->event_thread
->stop_pc (),
5623 ecs
->event_thread
, &ecs
->ws
);
5625 /* Note that this may be referenced from inside
5626 bpstat_stop_status above, through inferior_has_execd. */
5627 xfree (ecs
->ws
.value
.execd_pathname
);
5628 ecs
->ws
.value
.execd_pathname
= NULL
;
5630 if (handle_stop_requested (ecs
))
5633 /* If no catchpoint triggered for this, then keep going. */
5634 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5636 ecs
->event_thread
->set_stop_signal (GDB_SIGNAL_0
);
5640 process_event_stop_test (ecs
);
5643 /* Be careful not to try to gather much state about a thread
5644 that's in a syscall. It's frequently a losing proposition. */
5645 case TARGET_WAITKIND_SYSCALL_ENTRY
:
5646 /* Getting the current syscall number. */
5647 if (handle_syscall_event (ecs
) == 0)
5648 process_event_stop_test (ecs
);
5651 /* Before examining the threads further, step this thread to
5652 get it entirely out of the syscall. (We get notice of the
5653 event when the thread is just on the verge of exiting a
5654 syscall. Stepping one instruction seems to get it back
5656 case TARGET_WAITKIND_SYSCALL_RETURN
:
5657 if (handle_syscall_event (ecs
) == 0)
5658 process_event_stop_test (ecs
);
5661 case TARGET_WAITKIND_STOPPED
:
5662 handle_signal_stop (ecs
);
5665 case TARGET_WAITKIND_NO_HISTORY
:
5666 /* Reverse execution: target ran out of history info. */
5668 /* Switch to the stopped thread. */
5669 context_switch (ecs
);
5670 infrun_debug_printf ("stopped");
5672 delete_just_stopped_threads_single_step_breakpoints ();
5673 ecs
->event_thread
->set_stop_pc
5674 (regcache_read_pc (get_thread_regcache (inferior_thread ())));
5676 if (handle_stop_requested (ecs
))
5679 gdb::observers::no_history
.notify ();
5685 /* Restart threads back to what they were trying to do back when we
5686 paused them for an in-line step-over. The EVENT_THREAD thread is
5690 restart_threads (struct thread_info
*event_thread
)
5692 /* In case the instruction just stepped spawned a new thread. */
5693 update_thread_list ();
5695 for (thread_info
*tp
: all_non_exited_threads ())
5697 if (tp
->inf
->detaching
)
5699 infrun_debug_printf ("restart threads: [%s] inferior detaching",
5700 target_pid_to_str (tp
->ptid
).c_str ());
5704 switch_to_thread_no_regs (tp
);
5706 if (tp
== event_thread
)
5708 infrun_debug_printf ("restart threads: [%s] is event thread",
5709 target_pid_to_str (tp
->ptid
).c_str ());
5713 if (!(tp
->state
== THREAD_RUNNING
|| tp
->control
.in_infcall
))
5715 infrun_debug_printf ("restart threads: [%s] not meant to be running",
5716 target_pid_to_str (tp
->ptid
).c_str ());
5722 infrun_debug_printf ("restart threads: [%s] resumed",
5723 target_pid_to_str (tp
->ptid
).c_str ());
5724 gdb_assert (tp
->executing () || tp
->has_pending_waitstatus ());
5728 if (thread_is_in_step_over_chain (tp
))
5730 infrun_debug_printf ("restart threads: [%s] needs step-over",
5731 target_pid_to_str (tp
->ptid
).c_str ());
5732 gdb_assert (!tp
->resumed ());
5737 if (tp
->has_pending_waitstatus ())
5739 infrun_debug_printf ("restart threads: [%s] has pending status",
5740 target_pid_to_str (tp
->ptid
).c_str ());
5741 tp
->set_resumed (true);
5745 gdb_assert (!tp
->stop_requested
);
5747 /* If some thread needs to start a step-over at this point, it
5748 should still be in the step-over queue, and thus skipped
5750 if (thread_still_needs_step_over (tp
))
5752 internal_error (__FILE__
, __LINE__
,
5753 "thread [%s] needs a step-over, but not in "
5754 "step-over queue\n",
5755 target_pid_to_str (tp
->ptid
).c_str ());
5758 if (currently_stepping (tp
))
5760 infrun_debug_printf ("restart threads: [%s] was stepping",
5761 target_pid_to_str (tp
->ptid
).c_str ());
5762 keep_going_stepped_thread (tp
);
5766 struct execution_control_state ecss
;
5767 struct execution_control_state
*ecs
= &ecss
;
5769 infrun_debug_printf ("restart threads: [%s] continuing",
5770 target_pid_to_str (tp
->ptid
).c_str ());
5771 reset_ecs (ecs
, tp
);
5772 switch_to_thread (tp
);
5773 keep_going_pass_signal (ecs
);
5778 /* Callback for iterate_over_threads. Find a resumed thread that has
5779 a pending waitstatus. */
5782 resumed_thread_with_pending_status (struct thread_info
*tp
,
5785 return tp
->resumed () && tp
->has_pending_waitstatus ();
5788 /* Called when we get an event that may finish an in-line or
5789 out-of-line (displaced stepping) step-over started previously.
5790 Return true if the event is processed and we should go back to the
5791 event loop; false if the caller should continue processing the
5795 finish_step_over (struct execution_control_state
*ecs
)
5797 displaced_step_finish (ecs
->event_thread
, ecs
->event_thread
->stop_signal ());
5799 bool had_step_over_info
= step_over_info_valid_p ();
5801 if (had_step_over_info
)
5803 /* If we're stepping over a breakpoint with all threads locked,
5804 then only the thread that was stepped should be reporting
5806 gdb_assert (ecs
->event_thread
->control
.trap_expected
);
5808 clear_step_over_info ();
5811 if (!target_is_non_stop_p ())
5814 /* Start a new step-over in another thread if there's one that
5818 /* If we were stepping over a breakpoint before, and haven't started
5819 a new in-line step-over sequence, then restart all other threads
5820 (except the event thread). We can't do this in all-stop, as then
5821 e.g., we wouldn't be able to issue any other remote packet until
5822 these other threads stop. */
5823 if (had_step_over_info
&& !step_over_info_valid_p ())
5825 struct thread_info
*pending
;
5827 /* If we only have threads with pending statuses, the restart
5828 below won't restart any thread and so nothing re-inserts the
5829 breakpoint we just stepped over. But we need it inserted
5830 when we later process the pending events, otherwise if
5831 another thread has a pending event for this breakpoint too,
5832 we'd discard its event (because the breakpoint that
5833 originally caused the event was no longer inserted). */
5834 context_switch (ecs
);
5835 insert_breakpoints ();
5837 restart_threads (ecs
->event_thread
);
5839 /* If we have events pending, go through handle_inferior_event
5840 again, picking up a pending event at random. This avoids
5841 thread starvation. */
5843 /* But not if we just stepped over a watchpoint in order to let
5844 the instruction execute so we can evaluate its expression.
5845 The set of watchpoints that triggered is recorded in the
5846 breakpoint objects themselves (see bp->watchpoint_triggered).
5847 If we processed another event first, that other event could
5848 clobber this info. */
5849 if (ecs
->event_thread
->stepping_over_watchpoint
)
5852 pending
= iterate_over_threads (resumed_thread_with_pending_status
,
5854 if (pending
!= NULL
)
5856 struct thread_info
*tp
= ecs
->event_thread
;
5857 struct regcache
*regcache
;
5859 infrun_debug_printf ("found resumed threads with "
5860 "pending events, saving status");
5862 gdb_assert (pending
!= tp
);
5864 /* Record the event thread's event for later. */
5865 save_waitstatus (tp
, &ecs
->ws
);
5866 /* This was cleared early, by handle_inferior_event. Set it
5867 so this pending event is considered by
5869 tp
->set_resumed (true);
5871 gdb_assert (!tp
->executing ());
5873 regcache
= get_thread_regcache (tp
);
5874 tp
->set_stop_pc (regcache_read_pc (regcache
));
5876 infrun_debug_printf ("saved stop_pc=%s for %s "
5877 "(currently_stepping=%d)",
5878 paddress (target_gdbarch (), tp
->stop_pc ()),
5879 target_pid_to_str (tp
->ptid
).c_str (),
5880 currently_stepping (tp
));
5882 /* This in-line step-over finished; clear this so we won't
5883 start a new one. This is what handle_signal_stop would
5884 do, if we returned false. */
5885 tp
->stepping_over_breakpoint
= 0;
5887 /* Wake up the event loop again. */
5888 mark_async_event_handler (infrun_async_inferior_event_token
);
5890 prepare_to_wait (ecs
);
5898 /* Come here when the program has stopped with a signal. */
5901 handle_signal_stop (struct execution_control_state
*ecs
)
5903 struct frame_info
*frame
;
5904 struct gdbarch
*gdbarch
;
5905 int stopped_by_watchpoint
;
5906 enum stop_kind stop_soon
;
5909 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
5911 ecs
->event_thread
->set_stop_signal (ecs
->ws
.value
.sig
);
5913 /* Do we need to clean up the state of a thread that has
5914 completed a displaced single-step? (Doing so usually affects
5915 the PC, so do it here, before we set stop_pc.) */
5916 if (finish_step_over (ecs
))
5919 /* If we either finished a single-step or hit a breakpoint, but
5920 the user wanted this thread to be stopped, pretend we got a
5921 SIG0 (generic unsignaled stop). */
5922 if (ecs
->event_thread
->stop_requested
5923 && ecs
->event_thread
->stop_signal () == GDB_SIGNAL_TRAP
)
5924 ecs
->event_thread
->set_stop_signal (GDB_SIGNAL_0
);
5926 ecs
->event_thread
->set_stop_pc
5927 (regcache_read_pc (get_thread_regcache (ecs
->event_thread
)));
5929 context_switch (ecs
);
5931 if (deprecated_context_hook
)
5932 deprecated_context_hook (ecs
->event_thread
->global_num
);
5936 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
5937 struct gdbarch
*reg_gdbarch
= regcache
->arch ();
5940 ("stop_pc=%s", paddress (reg_gdbarch
, ecs
->event_thread
->stop_pc ()));
5941 if (target_stopped_by_watchpoint ())
5945 infrun_debug_printf ("stopped by watchpoint");
5947 if (target_stopped_data_address (current_inferior ()->top_target (),
5949 infrun_debug_printf ("stopped data address=%s",
5950 paddress (reg_gdbarch
, addr
));
5952 infrun_debug_printf ("(no data address available)");
5956 /* This is originated from start_remote(), start_inferior() and
5957 shared libraries hook functions. */
5958 stop_soon
= get_inferior_stop_soon (ecs
);
5959 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
5961 infrun_debug_printf ("quietly stopped");
5962 stop_print_frame
= true;
5967 /* This originates from attach_command(). We need to overwrite
5968 the stop_signal here, because some kernels don't ignore a
5969 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5970 See more comments in inferior.h. On the other hand, if we
5971 get a non-SIGSTOP, report it to the user - assume the backend
5972 will handle the SIGSTOP if it should show up later.
5974 Also consider that the attach is complete when we see a
5975 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5976 target extended-remote report it instead of a SIGSTOP
5977 (e.g. gdbserver). We already rely on SIGTRAP being our
5978 signal, so this is no exception.
5980 Also consider that the attach is complete when we see a
5981 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5982 the target to stop all threads of the inferior, in case the
5983 low level attach operation doesn't stop them implicitly. If
5984 they weren't stopped implicitly, then the stub will report a
5985 GDB_SIGNAL_0, meaning: stopped for no particular reason
5986 other than GDB's request. */
5987 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5988 && (ecs
->event_thread
->stop_signal () == GDB_SIGNAL_STOP
5989 || ecs
->event_thread
->stop_signal () == GDB_SIGNAL_TRAP
5990 || ecs
->event_thread
->stop_signal () == GDB_SIGNAL_0
))
5992 stop_print_frame
= true;
5994 ecs
->event_thread
->set_stop_signal (GDB_SIGNAL_0
);
5998 /* At this point, get hold of the now-current thread's frame. */
5999 frame
= get_current_frame ();
6000 gdbarch
= get_frame_arch (frame
);
6002 /* Pull the single step breakpoints out of the target. */
6003 if (ecs
->event_thread
->stop_signal () == GDB_SIGNAL_TRAP
)
6005 struct regcache
*regcache
;
6008 regcache
= get_thread_regcache (ecs
->event_thread
);
6009 const address_space
*aspace
= regcache
->aspace ();
6011 pc
= regcache_read_pc (regcache
);
6013 /* However, before doing so, if this single-step breakpoint was
6014 actually for another thread, set this thread up for moving
6016 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
6019 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
6021 infrun_debug_printf ("[%s] hit another thread's single-step "
6023 target_pid_to_str (ecs
->ptid
).c_str ());
6024 ecs
->hit_singlestep_breakpoint
= 1;
6029 infrun_debug_printf ("[%s] hit its single-step breakpoint",
6030 target_pid_to_str (ecs
->ptid
).c_str ());
6033 delete_just_stopped_threads_single_step_breakpoints ();
6035 if (ecs
->event_thread
->stop_signal () == GDB_SIGNAL_TRAP
6036 && ecs
->event_thread
->control
.trap_expected
6037 && ecs
->event_thread
->stepping_over_watchpoint
)
6038 stopped_by_watchpoint
= 0;
6040 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
6042 /* If necessary, step over this watchpoint. We'll be back to display
6044 if (stopped_by_watchpoint
6045 && (target_have_steppable_watchpoint ()
6046 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
6048 /* At this point, we are stopped at an instruction which has
6049 attempted to write to a piece of memory under control of
6050 a watchpoint. The instruction hasn't actually executed
6051 yet. If we were to evaluate the watchpoint expression
6052 now, we would get the old value, and therefore no change
6053 would seem to have occurred.
6055 In order to make watchpoints work `right', we really need
6056 to complete the memory write, and then evaluate the
6057 watchpoint expression. We do this by single-stepping the
6060 It may not be necessary to disable the watchpoint to step over
6061 it. For example, the PA can (with some kernel cooperation)
6062 single step over a watchpoint without disabling the watchpoint.
6064 It is far more common to need to disable a watchpoint to step
6065 the inferior over it. If we have non-steppable watchpoints,
6066 we must disable the current watchpoint; it's simplest to
6067 disable all watchpoints.
6069 Any breakpoint at PC must also be stepped over -- if there's
6070 one, it will have already triggered before the watchpoint
6071 triggered, and we either already reported it to the user, or
6072 it didn't cause a stop and we called keep_going. In either
6073 case, if there was a breakpoint at PC, we must be trying to
6075 ecs
->event_thread
->stepping_over_watchpoint
= 1;
6080 ecs
->event_thread
->stepping_over_breakpoint
= 0;
6081 ecs
->event_thread
->stepping_over_watchpoint
= 0;
6082 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
6083 ecs
->event_thread
->control
.stop_step
= 0;
6084 stop_print_frame
= true;
6085 stopped_by_random_signal
= 0;
6086 bpstat stop_chain
= NULL
;
6088 /* Hide inlined functions starting here, unless we just performed stepi or
6089 nexti. After stepi and nexti, always show the innermost frame (not any
6090 inline function call sites). */
6091 if (ecs
->event_thread
->control
.step_range_end
!= 1)
6093 const address_space
*aspace
6094 = get_thread_regcache (ecs
->event_thread
)->aspace ();
6096 /* skip_inline_frames is expensive, so we avoid it if we can
6097 determine that the address is one where functions cannot have
6098 been inlined. This improves performance with inferiors that
6099 load a lot of shared libraries, because the solib event
6100 breakpoint is defined as the address of a function (i.e. not
6101 inline). Note that we have to check the previous PC as well
6102 as the current one to catch cases when we have just
6103 single-stepped off a breakpoint prior to reinstating it.
6104 Note that we're assuming that the code we single-step to is
6105 not inline, but that's not definitive: there's nothing
6106 preventing the event breakpoint function from containing
6107 inlined code, and the single-step ending up there. If the
6108 user had set a breakpoint on that inlined code, the missing
6109 skip_inline_frames call would break things. Fortunately
6110 that's an extremely unlikely scenario. */
6111 if (!pc_at_non_inline_function (aspace
,
6112 ecs
->event_thread
->stop_pc (),
6114 && !(ecs
->event_thread
->stop_signal () == GDB_SIGNAL_TRAP
6115 && ecs
->event_thread
->control
.trap_expected
6116 && pc_at_non_inline_function (aspace
,
6117 ecs
->event_thread
->prev_pc
,
6120 stop_chain
= build_bpstat_chain (aspace
,
6121 ecs
->event_thread
->stop_pc (),
6123 skip_inline_frames (ecs
->event_thread
, stop_chain
);
6125 /* Re-fetch current thread's frame in case that invalidated
6127 frame
= get_current_frame ();
6128 gdbarch
= get_frame_arch (frame
);
6132 if (ecs
->event_thread
->stop_signal () == GDB_SIGNAL_TRAP
6133 && ecs
->event_thread
->control
.trap_expected
6134 && gdbarch_single_step_through_delay_p (gdbarch
)
6135 && currently_stepping (ecs
->event_thread
))
6137 /* We're trying to step off a breakpoint. Turns out that we're
6138 also on an instruction that needs to be stepped multiple
6139 times before it's been fully executing. E.g., architectures
6140 with a delay slot. It needs to be stepped twice, once for
6141 the instruction and once for the delay slot. */
6142 int step_through_delay
6143 = gdbarch_single_step_through_delay (gdbarch
, frame
);
6145 if (step_through_delay
)
6146 infrun_debug_printf ("step through delay");
6148 if (ecs
->event_thread
->control
.step_range_end
== 0
6149 && step_through_delay
)
6151 /* The user issued a continue when stopped at a breakpoint.
6152 Set up for another trap and get out of here. */
6153 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6157 else if (step_through_delay
)
6159 /* The user issued a step when stopped at a breakpoint.
6160 Maybe we should stop, maybe we should not - the delay
6161 slot *might* correspond to a line of source. In any
6162 case, don't decide that here, just set
6163 ecs->stepping_over_breakpoint, making sure we
6164 single-step again before breakpoints are re-inserted. */
6165 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6169 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
6170 handles this event. */
6171 ecs
->event_thread
->control
.stop_bpstat
6172 = bpstat_stop_status (get_current_regcache ()->aspace (),
6173 ecs
->event_thread
->stop_pc (),
6174 ecs
->event_thread
, &ecs
->ws
, stop_chain
);
6176 /* Following in case break condition called a
6178 stop_print_frame
= true;
6180 /* This is where we handle "moribund" watchpoints. Unlike
6181 software breakpoints traps, hardware watchpoint traps are
6182 always distinguishable from random traps. If no high-level
6183 watchpoint is associated with the reported stop data address
6184 anymore, then the bpstat does not explain the signal ---
6185 simply make sure to ignore it if `stopped_by_watchpoint' is
6188 if (ecs
->event_thread
->stop_signal () == GDB_SIGNAL_TRAP
6189 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
6191 && stopped_by_watchpoint
)
6193 infrun_debug_printf ("no user watchpoint explains watchpoint SIGTRAP, "
6197 /* NOTE: cagney/2003-03-29: These checks for a random signal
6198 at one stage in the past included checks for an inferior
6199 function call's call dummy's return breakpoint. The original
6200 comment, that went with the test, read:
6202 ``End of a stack dummy. Some systems (e.g. Sony news) give
6203 another signal besides SIGTRAP, so check here as well as
6206 If someone ever tries to get call dummys on a
6207 non-executable stack to work (where the target would stop
6208 with something like a SIGSEGV), then those tests might need
6209 to be re-instated. Given, however, that the tests were only
6210 enabled when momentary breakpoints were not being used, I
6211 suspect that it won't be the case.
6213 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
6214 be necessary for call dummies on a non-executable stack on
6217 /* See if the breakpoints module can explain the signal. */
6219 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
6220 ecs
->event_thread
->stop_signal ());
6222 /* Maybe this was a trap for a software breakpoint that has since
6224 if (random_signal
&& target_stopped_by_sw_breakpoint ())
6226 if (gdbarch_program_breakpoint_here_p (gdbarch
,
6227 ecs
->event_thread
->stop_pc ()))
6229 struct regcache
*regcache
;
6232 /* Re-adjust PC to what the program would see if GDB was not
6234 regcache
= get_thread_regcache (ecs
->event_thread
);
6235 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
6238 gdb::optional
<scoped_restore_tmpl
<int>>
6239 restore_operation_disable
;
6241 if (record_full_is_used ())
6242 restore_operation_disable
.emplace
6243 (record_full_gdb_operation_disable_set ());
6245 regcache_write_pc (regcache
,
6246 ecs
->event_thread
->stop_pc () + decr_pc
);
6251 /* A delayed software breakpoint event. Ignore the trap. */
6252 infrun_debug_printf ("delayed software breakpoint trap, ignoring");
6257 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
6258 has since been removed. */
6259 if (random_signal
&& target_stopped_by_hw_breakpoint ())
6261 /* A delayed hardware breakpoint event. Ignore the trap. */
6262 infrun_debug_printf ("delayed hardware breakpoint/watchpoint "
6267 /* If not, perhaps stepping/nexting can. */
6269 random_signal
= !(ecs
->event_thread
->stop_signal () == GDB_SIGNAL_TRAP
6270 && currently_stepping (ecs
->event_thread
));
6272 /* Perhaps the thread hit a single-step breakpoint of _another_
6273 thread. Single-step breakpoints are transparent to the
6274 breakpoints module. */
6276 random_signal
= !ecs
->hit_singlestep_breakpoint
;
6278 /* No? Perhaps we got a moribund watchpoint. */
6280 random_signal
= !stopped_by_watchpoint
;
6282 /* Always stop if the user explicitly requested this thread to
6284 if (ecs
->event_thread
->stop_requested
)
6287 infrun_debug_printf ("user-requested stop");
6290 /* For the program's own signals, act according to
6291 the signal handling tables. */
6295 /* Signal not for debugging purposes. */
6296 enum gdb_signal stop_signal
= ecs
->event_thread
->stop_signal ();
6298 infrun_debug_printf ("random signal (%s)",
6299 gdb_signal_to_symbol_string (stop_signal
));
6301 stopped_by_random_signal
= 1;
6303 /* Always stop on signals if we're either just gaining control
6304 of the program, or the user explicitly requested this thread
6305 to remain stopped. */
6306 if (stop_soon
!= NO_STOP_QUIETLY
6307 || ecs
->event_thread
->stop_requested
6308 || signal_stop_state (ecs
->event_thread
->stop_signal ()))
6314 /* Notify observers the signal has "handle print" set. Note we
6315 returned early above if stopping; normal_stop handles the
6316 printing in that case. */
6317 if (signal_print
[ecs
->event_thread
->stop_signal ()])
6319 /* The signal table tells us to print about this signal. */
6320 target_terminal::ours_for_output ();
6321 gdb::observers::signal_received
.notify (ecs
->event_thread
->stop_signal ());
6322 target_terminal::inferior ();
6325 /* Clear the signal if it should not be passed. */
6326 if (signal_program
[ecs
->event_thread
->stop_signal ()] == 0)
6327 ecs
->event_thread
->set_stop_signal (GDB_SIGNAL_0
);
6329 if (ecs
->event_thread
->prev_pc
== ecs
->event_thread
->stop_pc ()
6330 && ecs
->event_thread
->control
.trap_expected
6331 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6333 /* We were just starting a new sequence, attempting to
6334 single-step off of a breakpoint and expecting a SIGTRAP.
6335 Instead this signal arrives. This signal will take us out
6336 of the stepping range so GDB needs to remember to, when
6337 the signal handler returns, resume stepping off that
6339 /* To simplify things, "continue" is forced to use the same
6340 code paths as single-step - set a breakpoint at the
6341 signal return address and then, once hit, step off that
6343 infrun_debug_printf ("signal arrived while stepping over breakpoint");
6345 insert_hp_step_resume_breakpoint_at_frame (frame
);
6346 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6347 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6348 ecs
->event_thread
->control
.trap_expected
= 0;
6350 /* If we were nexting/stepping some other thread, switch to
6351 it, so that we don't continue it, losing control. */
6352 if (!switch_back_to_stepped_thread (ecs
))
6357 if (ecs
->event_thread
->stop_signal () != GDB_SIGNAL_0
6358 && (pc_in_thread_step_range (ecs
->event_thread
->stop_pc (),
6360 || ecs
->event_thread
->control
.step_range_end
== 1)
6361 && frame_id_eq (get_stack_frame_id (frame
),
6362 ecs
->event_thread
->control
.step_stack_frame_id
)
6363 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6365 /* The inferior is about to take a signal that will take it
6366 out of the single step range. Set a breakpoint at the
6367 current PC (which is presumably where the signal handler
6368 will eventually return) and then allow the inferior to
6371 Note that this is only needed for a signal delivered
6372 while in the single-step range. Nested signals aren't a
6373 problem as they eventually all return. */
6374 infrun_debug_printf ("signal may take us out of single-step range");
6376 clear_step_over_info ();
6377 insert_hp_step_resume_breakpoint_at_frame (frame
);
6378 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6379 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6380 ecs
->event_thread
->control
.trap_expected
= 0;
6385 /* Note: step_resume_breakpoint may be non-NULL. This occurs
6386 when either there's a nested signal, or when there's a
6387 pending signal enabled just as the signal handler returns
6388 (leaving the inferior at the step-resume-breakpoint without
6389 actually executing it). Either way continue until the
6390 breakpoint is really hit. */
6392 if (!switch_back_to_stepped_thread (ecs
))
6394 infrun_debug_printf ("random signal, keep going");
6401 process_event_stop_test (ecs
);
6404 /* Come here when we've got some debug event / signal we can explain
6405 (IOW, not a random signal), and test whether it should cause a
6406 stop, or whether we should resume the inferior (transparently).
6407 E.g., could be a breakpoint whose condition evaluates false; we
6408 could be still stepping within the line; etc. */
6411 process_event_stop_test (struct execution_control_state
*ecs
)
6413 struct symtab_and_line stop_pc_sal
;
6414 struct frame_info
*frame
;
6415 struct gdbarch
*gdbarch
;
6416 CORE_ADDR jmp_buf_pc
;
6417 struct bpstat_what what
;
6419 /* Handle cases caused by hitting a breakpoint. */
6421 frame
= get_current_frame ();
6422 gdbarch
= get_frame_arch (frame
);
6424 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
6426 if (what
.call_dummy
)
6428 stop_stack_dummy
= what
.call_dummy
;
6431 /* A few breakpoint types have callbacks associated (e.g.,
6432 bp_jit_event). Run them now. */
6433 bpstat_run_callbacks (ecs
->event_thread
->control
.stop_bpstat
);
6435 /* If we hit an internal event that triggers symbol changes, the
6436 current frame will be invalidated within bpstat_what (e.g., if we
6437 hit an internal solib event). Re-fetch it. */
6438 frame
= get_current_frame ();
6439 gdbarch
= get_frame_arch (frame
);
6441 switch (what
.main_action
)
6443 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
6444 /* If we hit the breakpoint at longjmp while stepping, we
6445 install a momentary breakpoint at the target of the
6448 infrun_debug_printf ("BPSTAT_WHAT_SET_LONGJMP_RESUME");
6450 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6452 if (what
.is_longjmp
)
6454 struct value
*arg_value
;
6456 /* If we set the longjmp breakpoint via a SystemTap probe,
6457 then use it to extract the arguments. The destination PC
6458 is the third argument to the probe. */
6459 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
6462 jmp_buf_pc
= value_as_address (arg_value
);
6463 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
6465 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
6466 || !gdbarch_get_longjmp_target (gdbarch
,
6467 frame
, &jmp_buf_pc
))
6469 infrun_debug_printf ("BPSTAT_WHAT_SET_LONGJMP_RESUME "
6470 "(!gdbarch_get_longjmp_target)");
6475 /* Insert a breakpoint at resume address. */
6476 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
6479 check_exception_resume (ecs
, frame
);
6483 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
6485 struct frame_info
*init_frame
;
6487 /* There are several cases to consider.
6489 1. The initiating frame no longer exists. In this case we
6490 must stop, because the exception or longjmp has gone too
6493 2. The initiating frame exists, and is the same as the
6494 current frame. We stop, because the exception or longjmp
6497 3. The initiating frame exists and is different from the
6498 current frame. This means the exception or longjmp has
6499 been caught beneath the initiating frame, so keep going.
6501 4. longjmp breakpoint has been placed just to protect
6502 against stale dummy frames and user is not interested in
6503 stopping around longjmps. */
6505 infrun_debug_printf ("BPSTAT_WHAT_CLEAR_LONGJMP_RESUME");
6507 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
6509 delete_exception_resume_breakpoint (ecs
->event_thread
);
6511 if (what
.is_longjmp
)
6513 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
6515 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
6523 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
6527 struct frame_id current_id
6528 = get_frame_id (get_current_frame ());
6529 if (frame_id_eq (current_id
,
6530 ecs
->event_thread
->initiating_frame
))
6532 /* Case 2. Fall through. */
6542 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6544 delete_step_resume_breakpoint (ecs
->event_thread
);
6546 end_stepping_range (ecs
);
6550 case BPSTAT_WHAT_SINGLE
:
6551 infrun_debug_printf ("BPSTAT_WHAT_SINGLE");
6552 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6553 /* Still need to check other stuff, at least the case where we
6554 are stepping and step out of the right range. */
6557 case BPSTAT_WHAT_STEP_RESUME
:
6558 infrun_debug_printf ("BPSTAT_WHAT_STEP_RESUME");
6560 delete_step_resume_breakpoint (ecs
->event_thread
);
6561 if (ecs
->event_thread
->control
.proceed_to_finish
6562 && execution_direction
== EXEC_REVERSE
)
6564 struct thread_info
*tp
= ecs
->event_thread
;
6566 /* We are finishing a function in reverse, and just hit the
6567 step-resume breakpoint at the start address of the
6568 function, and we're almost there -- just need to back up
6569 by one more single-step, which should take us back to the
6571 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
6575 fill_in_stop_func (gdbarch
, ecs
);
6576 if (ecs
->event_thread
->stop_pc () == ecs
->stop_func_start
6577 && execution_direction
== EXEC_REVERSE
)
6579 /* We are stepping over a function call in reverse, and just
6580 hit the step-resume breakpoint at the start address of
6581 the function. Go back to single-stepping, which should
6582 take us back to the function call. */
6583 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6589 case BPSTAT_WHAT_STOP_NOISY
:
6590 infrun_debug_printf ("BPSTAT_WHAT_STOP_NOISY");
6591 stop_print_frame
= true;
6593 /* Assume the thread stopped for a breakpoint. We'll still check
6594 whether a/the breakpoint is there when the thread is next
6596 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6601 case BPSTAT_WHAT_STOP_SILENT
:
6602 infrun_debug_printf ("BPSTAT_WHAT_STOP_SILENT");
6603 stop_print_frame
= false;
6605 /* Assume the thread stopped for a breakpoint. We'll still check
6606 whether a/the breakpoint is there when the thread is next
6608 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6612 case BPSTAT_WHAT_HP_STEP_RESUME
:
6613 infrun_debug_printf ("BPSTAT_WHAT_HP_STEP_RESUME");
6615 delete_step_resume_breakpoint (ecs
->event_thread
);
6616 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
6618 /* Back when the step-resume breakpoint was inserted, we
6619 were trying to single-step off a breakpoint. Go back to
6621 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6622 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6628 case BPSTAT_WHAT_KEEP_CHECKING
:
6632 /* If we stepped a permanent breakpoint and we had a high priority
6633 step-resume breakpoint for the address we stepped, but we didn't
6634 hit it, then we must have stepped into the signal handler. The
6635 step-resume was only necessary to catch the case of _not_
6636 stepping into the handler, so delete it, and fall through to
6637 checking whether the step finished. */
6638 if (ecs
->event_thread
->stepped_breakpoint
)
6640 struct breakpoint
*sr_bp
6641 = ecs
->event_thread
->control
.step_resume_breakpoint
;
6644 && sr_bp
->loc
->permanent
6645 && sr_bp
->type
== bp_hp_step_resume
6646 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
6648 infrun_debug_printf ("stepped permanent breakpoint, stopped in handler");
6649 delete_step_resume_breakpoint (ecs
->event_thread
);
6650 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6654 /* We come here if we hit a breakpoint but should not stop for it.
6655 Possibly we also were stepping and should stop for that. So fall
6656 through and test for stepping. But, if not stepping, do not
6659 /* In all-stop mode, if we're currently stepping but have stopped in
6660 some other thread, we need to switch back to the stepped thread. */
6661 if (switch_back_to_stepped_thread (ecs
))
6664 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
6666 infrun_debug_printf ("step-resume breakpoint is inserted");
6668 /* Having a step-resume breakpoint overrides anything
6669 else having to do with stepping commands until
6670 that breakpoint is reached. */
6675 if (ecs
->event_thread
->control
.step_range_end
== 0)
6677 infrun_debug_printf ("no stepping, continue");
6678 /* Likewise if we aren't even stepping. */
6683 /* Re-fetch current thread's frame in case the code above caused
6684 the frame cache to be re-initialized, making our FRAME variable
6685 a dangling pointer. */
6686 frame
= get_current_frame ();
6687 gdbarch
= get_frame_arch (frame
);
6688 fill_in_stop_func (gdbarch
, ecs
);
6690 /* If stepping through a line, keep going if still within it.
6692 Note that step_range_end is the address of the first instruction
6693 beyond the step range, and NOT the address of the last instruction
6696 Note also that during reverse execution, we may be stepping
6697 through a function epilogue and therefore must detect when
6698 the current-frame changes in the middle of a line. */
6700 if (pc_in_thread_step_range (ecs
->event_thread
->stop_pc (),
6702 && (execution_direction
!= EXEC_REVERSE
6703 || frame_id_eq (get_frame_id (frame
),
6704 ecs
->event_thread
->control
.step_frame_id
)))
6707 ("stepping inside range [%s-%s]",
6708 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
6709 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
6711 /* Tentatively re-enable range stepping; `resume' disables it if
6712 necessary (e.g., if we're stepping over a breakpoint or we
6713 have software watchpoints). */
6714 ecs
->event_thread
->control
.may_range_step
= 1;
6716 /* When stepping backward, stop at beginning of line range
6717 (unless it's the function entry point, in which case
6718 keep going back to the call point). */
6719 CORE_ADDR stop_pc
= ecs
->event_thread
->stop_pc ();
6720 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
6721 && stop_pc
!= ecs
->stop_func_start
6722 && execution_direction
== EXEC_REVERSE
)
6723 end_stepping_range (ecs
);
6730 /* We stepped out of the stepping range. */
6732 /* If we are stepping at the source level and entered the runtime
6733 loader dynamic symbol resolution code...
6735 EXEC_FORWARD: we keep on single stepping until we exit the run
6736 time loader code and reach the callee's address.
6738 EXEC_REVERSE: we've already executed the callee (backward), and
6739 the runtime loader code is handled just like any other
6740 undebuggable function call. Now we need only keep stepping
6741 backward through the trampoline code, and that's handled further
6742 down, so there is nothing for us to do here. */
6744 if (execution_direction
!= EXEC_REVERSE
6745 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6746 && in_solib_dynsym_resolve_code (ecs
->event_thread
->stop_pc ()))
6748 CORE_ADDR pc_after_resolver
=
6749 gdbarch_skip_solib_resolver (gdbarch
, ecs
->event_thread
->stop_pc ());
6751 infrun_debug_printf ("stepped into dynsym resolve code");
6753 if (pc_after_resolver
)
6755 /* Set up a step-resume breakpoint at the address
6756 indicated by SKIP_SOLIB_RESOLVER. */
6757 symtab_and_line sr_sal
;
6758 sr_sal
.pc
= pc_after_resolver
;
6759 sr_sal
.pspace
= get_frame_program_space (frame
);
6761 insert_step_resume_breakpoint_at_sal (gdbarch
,
6762 sr_sal
, null_frame_id
);
6769 /* Step through an indirect branch thunk. */
6770 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6771 && gdbarch_in_indirect_branch_thunk (gdbarch
,
6772 ecs
->event_thread
->stop_pc ()))
6774 infrun_debug_printf ("stepped into indirect branch thunk");
6779 if (ecs
->event_thread
->control
.step_range_end
!= 1
6780 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6781 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6782 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
6784 infrun_debug_printf ("stepped into signal trampoline");
6785 /* The inferior, while doing a "step" or "next", has ended up in
6786 a signal trampoline (either by a signal being delivered or by
6787 the signal handler returning). Just single-step until the
6788 inferior leaves the trampoline (either by calling the handler
6794 /* If we're in the return path from a shared library trampoline,
6795 we want to proceed through the trampoline when stepping. */
6796 /* macro/2012-04-25: This needs to come before the subroutine
6797 call check below as on some targets return trampolines look
6798 like subroutine calls (MIPS16 return thunks). */
6799 if (gdbarch_in_solib_return_trampoline (gdbarch
,
6800 ecs
->event_thread
->stop_pc (),
6801 ecs
->stop_func_name
)
6802 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6804 /* Determine where this trampoline returns. */
6805 CORE_ADDR stop_pc
= ecs
->event_thread
->stop_pc ();
6806 CORE_ADDR real_stop_pc
6807 = gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6809 infrun_debug_printf ("stepped into solib return tramp");
6811 /* Only proceed through if we know where it's going. */
6814 /* And put the step-breakpoint there and go until there. */
6815 symtab_and_line sr_sal
;
6816 sr_sal
.pc
= real_stop_pc
;
6817 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6818 sr_sal
.pspace
= get_frame_program_space (frame
);
6820 /* Do not specify what the fp should be when we stop since
6821 on some machines the prologue is where the new fp value
6823 insert_step_resume_breakpoint_at_sal (gdbarch
,
6824 sr_sal
, null_frame_id
);
6826 /* Restart without fiddling with the step ranges or
6833 /* Check for subroutine calls. The check for the current frame
6834 equalling the step ID is not necessary - the check of the
6835 previous frame's ID is sufficient - but it is a common case and
6836 cheaper than checking the previous frame's ID.
6838 NOTE: frame_id_eq will never report two invalid frame IDs as
6839 being equal, so to get into this block, both the current and
6840 previous frame must have valid frame IDs. */
6841 /* The outer_frame_id check is a heuristic to detect stepping
6842 through startup code. If we step over an instruction which
6843 sets the stack pointer from an invalid value to a valid value,
6844 we may detect that as a subroutine call from the mythical
6845 "outermost" function. This could be fixed by marking
6846 outermost frames as !stack_p,code_p,special_p. Then the
6847 initial outermost frame, before sp was valid, would
6848 have code_addr == &_start. See the comment in frame_id_eq
6850 if (!frame_id_eq (get_stack_frame_id (frame
),
6851 ecs
->event_thread
->control
.step_stack_frame_id
)
6852 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6853 ecs
->event_thread
->control
.step_stack_frame_id
)
6854 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
6856 || (ecs
->event_thread
->control
.step_start_function
6857 != find_pc_function (ecs
->event_thread
->stop_pc ())))))
6859 CORE_ADDR stop_pc
= ecs
->event_thread
->stop_pc ();
6860 CORE_ADDR real_stop_pc
;
6862 infrun_debug_printf ("stepped into subroutine");
6864 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
6866 /* I presume that step_over_calls is only 0 when we're
6867 supposed to be stepping at the assembly language level
6868 ("stepi"). Just stop. */
6869 /* And this works the same backward as frontward. MVS */
6870 end_stepping_range (ecs
);
6874 /* Reverse stepping through solib trampolines. */
6876 if (execution_direction
== EXEC_REVERSE
6877 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6878 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6879 || (ecs
->stop_func_start
== 0
6880 && in_solib_dynsym_resolve_code (stop_pc
))))
6882 /* Any solib trampoline code can be handled in reverse
6883 by simply continuing to single-step. We have already
6884 executed the solib function (backwards), and a few
6885 steps will take us back through the trampoline to the
6891 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6893 /* We're doing a "next".
6895 Normal (forward) execution: set a breakpoint at the
6896 callee's return address (the address at which the caller
6899 Reverse (backward) execution. set the step-resume
6900 breakpoint at the start of the function that we just
6901 stepped into (backwards), and continue to there. When we
6902 get there, we'll need to single-step back to the caller. */
6904 if (execution_direction
== EXEC_REVERSE
)
6906 /* If we're already at the start of the function, we've either
6907 just stepped backward into a single instruction function,
6908 or stepped back out of a signal handler to the first instruction
6909 of the function. Just keep going, which will single-step back
6911 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
6913 /* Normal function call return (static or dynamic). */
6914 symtab_and_line sr_sal
;
6915 sr_sal
.pc
= ecs
->stop_func_start
;
6916 sr_sal
.pspace
= get_frame_program_space (frame
);
6917 insert_step_resume_breakpoint_at_sal (gdbarch
,
6918 sr_sal
, null_frame_id
);
6922 insert_step_resume_breakpoint_at_caller (frame
);
6928 /* If we are in a function call trampoline (a stub between the
6929 calling routine and the real function), locate the real
6930 function. That's what tells us (a) whether we want to step
6931 into it at all, and (b) what prologue we want to run to the
6932 end of, if we do step into it. */
6933 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
6934 if (real_stop_pc
== 0)
6935 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6936 if (real_stop_pc
!= 0)
6937 ecs
->stop_func_start
= real_stop_pc
;
6939 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
6941 symtab_and_line sr_sal
;
6942 sr_sal
.pc
= ecs
->stop_func_start
;
6943 sr_sal
.pspace
= get_frame_program_space (frame
);
6945 insert_step_resume_breakpoint_at_sal (gdbarch
,
6946 sr_sal
, null_frame_id
);
6951 /* If we have line number information for the function we are
6952 thinking of stepping into and the function isn't on the skip
6955 If there are several symtabs at that PC (e.g. with include
6956 files), just want to know whether *any* of them have line
6957 numbers. find_pc_line handles this. */
6959 struct symtab_and_line tmp_sal
;
6961 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
6962 if (tmp_sal
.line
!= 0
6963 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
6965 && !inline_frame_is_marked_for_skip (true, ecs
->event_thread
))
6967 if (execution_direction
== EXEC_REVERSE
)
6968 handle_step_into_function_backward (gdbarch
, ecs
);
6970 handle_step_into_function (gdbarch
, ecs
);
6975 /* If we have no line number and the step-stop-if-no-debug is
6976 set, we stop the step so that the user has a chance to switch
6977 in assembly mode. */
6978 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6979 && step_stop_if_no_debug
)
6981 end_stepping_range (ecs
);
6985 if (execution_direction
== EXEC_REVERSE
)
6987 /* If we're already at the start of the function, we've either just
6988 stepped backward into a single instruction function without line
6989 number info, or stepped back out of a signal handler to the first
6990 instruction of the function without line number info. Just keep
6991 going, which will single-step back to the caller. */
6992 if (ecs
->stop_func_start
!= stop_pc
)
6994 /* Set a breakpoint at callee's start address.
6995 From there we can step once and be back in the caller. */
6996 symtab_and_line sr_sal
;
6997 sr_sal
.pc
= ecs
->stop_func_start
;
6998 sr_sal
.pspace
= get_frame_program_space (frame
);
6999 insert_step_resume_breakpoint_at_sal (gdbarch
,
7000 sr_sal
, null_frame_id
);
7004 /* Set a breakpoint at callee's return address (the address
7005 at which the caller will resume). */
7006 insert_step_resume_breakpoint_at_caller (frame
);
7012 /* Reverse stepping through solib trampolines. */
7014 if (execution_direction
== EXEC_REVERSE
7015 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
7017 CORE_ADDR stop_pc
= ecs
->event_thread
->stop_pc ();
7019 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
7020 || (ecs
->stop_func_start
== 0
7021 && in_solib_dynsym_resolve_code (stop_pc
)))
7023 /* Any solib trampoline code can be handled in reverse
7024 by simply continuing to single-step. We have already
7025 executed the solib function (backwards), and a few
7026 steps will take us back through the trampoline to the
7031 else if (in_solib_dynsym_resolve_code (stop_pc
))
7033 /* Stepped backward into the solib dynsym resolver.
7034 Set a breakpoint at its start and continue, then
7035 one more step will take us out. */
7036 symtab_and_line sr_sal
;
7037 sr_sal
.pc
= ecs
->stop_func_start
;
7038 sr_sal
.pspace
= get_frame_program_space (frame
);
7039 insert_step_resume_breakpoint_at_sal (gdbarch
,
7040 sr_sal
, null_frame_id
);
7046 /* This always returns the sal for the inner-most frame when we are in a
7047 stack of inlined frames, even if GDB actually believes that it is in a
7048 more outer frame. This is checked for below by calls to
7049 inline_skipped_frames. */
7050 stop_pc_sal
= find_pc_line (ecs
->event_thread
->stop_pc (), 0);
7052 /* NOTE: tausq/2004-05-24: This if block used to be done before all
7053 the trampoline processing logic, however, there are some trampolines
7054 that have no names, so we should do trampoline handling first. */
7055 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
7056 && ecs
->stop_func_name
== NULL
7057 && stop_pc_sal
.line
== 0)
7059 infrun_debug_printf ("stepped into undebuggable function");
7061 /* The inferior just stepped into, or returned to, an
7062 undebuggable function (where there is no debugging information
7063 and no line number corresponding to the address where the
7064 inferior stopped). Since we want to skip this kind of code,
7065 we keep going until the inferior returns from this
7066 function - unless the user has asked us not to (via
7067 set step-mode) or we no longer know how to get back
7068 to the call site. */
7069 if (step_stop_if_no_debug
7070 || !frame_id_p (frame_unwind_caller_id (frame
)))
7072 /* If we have no line number and the step-stop-if-no-debug
7073 is set, we stop the step so that the user has a chance to
7074 switch in assembly mode. */
7075 end_stepping_range (ecs
);
7080 /* Set a breakpoint at callee's return address (the address
7081 at which the caller will resume). */
7082 insert_step_resume_breakpoint_at_caller (frame
);
7088 if (ecs
->event_thread
->control
.step_range_end
== 1)
7090 /* It is stepi or nexti. We always want to stop stepping after
7092 infrun_debug_printf ("stepi/nexti");
7093 end_stepping_range (ecs
);
7097 if (stop_pc_sal
.line
== 0)
7099 /* We have no line number information. That means to stop
7100 stepping (does this always happen right after one instruction,
7101 when we do "s" in a function with no line numbers,
7102 or can this happen as a result of a return or longjmp?). */
7103 infrun_debug_printf ("line number info");
7104 end_stepping_range (ecs
);
7108 /* Look for "calls" to inlined functions, part one. If the inline
7109 frame machinery detected some skipped call sites, we have entered
7110 a new inline function. */
7112 if (frame_id_eq (get_frame_id (get_current_frame ()),
7113 ecs
->event_thread
->control
.step_frame_id
)
7114 && inline_skipped_frames (ecs
->event_thread
))
7116 infrun_debug_printf ("stepped into inlined function");
7118 symtab_and_line call_sal
= find_frame_sal (get_current_frame ());
7120 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
7122 /* For "step", we're going to stop. But if the call site
7123 for this inlined function is on the same source line as
7124 we were previously stepping, go down into the function
7125 first. Otherwise stop at the call site. */
7127 if (call_sal
.line
== ecs
->event_thread
->current_line
7128 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
7130 step_into_inline_frame (ecs
->event_thread
);
7131 if (inline_frame_is_marked_for_skip (false, ecs
->event_thread
))
7138 end_stepping_range (ecs
);
7143 /* For "next", we should stop at the call site if it is on a
7144 different source line. Otherwise continue through the
7145 inlined function. */
7146 if (call_sal
.line
== ecs
->event_thread
->current_line
7147 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
7150 end_stepping_range (ecs
);
7155 /* Look for "calls" to inlined functions, part two. If we are still
7156 in the same real function we were stepping through, but we have
7157 to go further up to find the exact frame ID, we are stepping
7158 through a more inlined call beyond its call site. */
7160 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
7161 && !frame_id_eq (get_frame_id (get_current_frame ()),
7162 ecs
->event_thread
->control
.step_frame_id
)
7163 && stepped_in_from (get_current_frame (),
7164 ecs
->event_thread
->control
.step_frame_id
))
7166 infrun_debug_printf ("stepping through inlined function");
7168 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
7169 || inline_frame_is_marked_for_skip (false, ecs
->event_thread
))
7172 end_stepping_range (ecs
);
7176 bool refresh_step_info
= true;
7177 if ((ecs
->event_thread
->stop_pc () == stop_pc_sal
.pc
)
7178 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
7179 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
7181 /* We are at a different line. */
7183 if (stop_pc_sal
.is_stmt
)
7185 /* We are at the start of a statement.
7187 So stop. Note that we don't stop if we step into the middle of a
7188 statement. That is said to make things like for (;;) statements
7190 infrun_debug_printf ("stepped to a different line");
7191 end_stepping_range (ecs
);
7194 else if (frame_id_eq (get_frame_id (get_current_frame ()),
7195 ecs
->event_thread
->control
.step_frame_id
))
7197 /* We are not at the start of a statement, and we have not changed
7200 We ignore this line table entry, and continue stepping forward,
7201 looking for a better place to stop. */
7202 refresh_step_info
= false;
7203 infrun_debug_printf ("stepped to a different line, but "
7204 "it's not the start of a statement");
7208 /* We are not the start of a statement, and we have changed frame.
7210 We ignore this line table entry, and continue stepping forward,
7211 looking for a better place to stop. Keep refresh_step_info at
7212 true to note that the frame has changed, but ignore the line
7213 number to make sure we don't ignore a subsequent entry with the
7214 same line number. */
7215 stop_pc_sal
.line
= 0;
7216 infrun_debug_printf ("stepped to a different frame, but "
7217 "it's not the start of a statement");
7221 /* We aren't done stepping.
7223 Optimize by setting the stepping range to the line.
7224 (We might not be in the original line, but if we entered a
7225 new line in mid-statement, we continue stepping. This makes
7226 things like for(;;) statements work better.)
7228 If we entered a SAL that indicates a non-statement line table entry,
7229 then we update the stepping range, but we don't update the step info,
7230 which includes things like the line number we are stepping away from.
7231 This means we will stop when we find a line table entry that is marked
7232 as is-statement, even if it matches the non-statement one we just
7235 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
7236 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
7237 ecs
->event_thread
->control
.may_range_step
= 1;
7238 if (refresh_step_info
)
7239 set_step_info (ecs
->event_thread
, frame
, stop_pc_sal
);
7241 infrun_debug_printf ("keep going");
7245 static bool restart_stepped_thread (process_stratum_target
*resume_target
,
7246 ptid_t resume_ptid
);
7248 /* In all-stop mode, if we're currently stepping but have stopped in
7249 some other thread, we may need to switch back to the stepped
7250 thread. Returns true we set the inferior running, false if we left
7251 it stopped (and the event needs further processing). */
7254 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
7256 if (!target_is_non_stop_p ())
7258 /* If any thread is blocked on some internal breakpoint, and we
7259 simply need to step over that breakpoint to get it going
7260 again, do that first. */
7262 /* However, if we see an event for the stepping thread, then we
7263 know all other threads have been moved past their breakpoints
7264 already. Let the caller check whether the step is finished,
7265 etc., before deciding to move it past a breakpoint. */
7266 if (ecs
->event_thread
->control
.step_range_end
!= 0)
7269 /* Check if the current thread is blocked on an incomplete
7270 step-over, interrupted by a random signal. */
7271 if (ecs
->event_thread
->control
.trap_expected
7272 && ecs
->event_thread
->stop_signal () != GDB_SIGNAL_TRAP
)
7275 ("need to finish step-over of [%s]",
7276 target_pid_to_str (ecs
->event_thread
->ptid
).c_str ());
7281 /* Check if the current thread is blocked by a single-step
7282 breakpoint of another thread. */
7283 if (ecs
->hit_singlestep_breakpoint
)
7285 infrun_debug_printf ("need to step [%s] over single-step breakpoint",
7286 target_pid_to_str (ecs
->ptid
).c_str ());
7291 /* If this thread needs yet another step-over (e.g., stepping
7292 through a delay slot), do it first before moving on to
7294 if (thread_still_needs_step_over (ecs
->event_thread
))
7297 ("thread [%s] still needs step-over",
7298 target_pid_to_str (ecs
->event_thread
->ptid
).c_str ());
7303 /* If scheduler locking applies even if not stepping, there's no
7304 need to walk over threads. Above we've checked whether the
7305 current thread is stepping. If some other thread not the
7306 event thread is stepping, then it must be that scheduler
7307 locking is not in effect. */
7308 if (schedlock_applies (ecs
->event_thread
))
7311 /* Otherwise, we no longer expect a trap in the current thread.
7312 Clear the trap_expected flag before switching back -- this is
7313 what keep_going does as well, if we call it. */
7314 ecs
->event_thread
->control
.trap_expected
= 0;
7316 /* Likewise, clear the signal if it should not be passed. */
7317 if (!signal_program
[ecs
->event_thread
->stop_signal ()])
7318 ecs
->event_thread
->set_stop_signal (GDB_SIGNAL_0
);
7320 if (restart_stepped_thread (ecs
->target
, ecs
->ptid
))
7322 prepare_to_wait (ecs
);
7326 switch_to_thread (ecs
->event_thread
);
7332 /* Look for the thread that was stepping, and resume it.
7333 RESUME_TARGET / RESUME_PTID indicate the set of threads the caller
7334 is resuming. Return true if a thread was started, false
7338 restart_stepped_thread (process_stratum_target
*resume_target
,
7341 /* Do all pending step-overs before actually proceeding with
7343 if (start_step_over ())
7346 for (thread_info
*tp
: all_threads_safe ())
7348 if (tp
->state
== THREAD_EXITED
)
7351 if (tp
->has_pending_waitstatus ())
7354 /* Ignore threads of processes the caller is not
7357 && (tp
->inf
->process_target () != resume_target
7358 || tp
->inf
->pid
!= resume_ptid
.pid ()))
7361 if (tp
->control
.trap_expected
)
7363 infrun_debug_printf ("switching back to stepped thread (step-over)");
7365 if (keep_going_stepped_thread (tp
))
7370 for (thread_info
*tp
: all_threads_safe ())
7372 if (tp
->state
== THREAD_EXITED
)
7375 if (tp
->has_pending_waitstatus ())
7378 /* Ignore threads of processes the caller is not
7381 && (tp
->inf
->process_target () != resume_target
7382 || tp
->inf
->pid
!= resume_ptid
.pid ()))
7385 /* Did we find the stepping thread? */
7386 if (tp
->control
.step_range_end
)
7388 infrun_debug_printf ("switching back to stepped thread (stepping)");
7390 if (keep_going_stepped_thread (tp
))
7401 restart_after_all_stop_detach (process_stratum_target
*proc_target
)
7403 /* Note we don't check target_is_non_stop_p() here, because the
7404 current inferior may no longer have a process_stratum target
7405 pushed, as we just detached. */
7407 /* See if we have a THREAD_RUNNING thread that need to be
7408 re-resumed. If we have any thread that is already executing,
7409 then we don't need to resume the target -- it is already been
7410 resumed. With the remote target (in all-stop), it's even
7411 impossible to issue another resumption if the target is already
7412 resumed, until the target reports a stop. */
7413 for (thread_info
*thr
: all_threads (proc_target
))
7415 if (thr
->state
!= THREAD_RUNNING
)
7418 /* If we have any thread that is already executing, then we
7419 don't need to resume the target -- it is already been
7421 if (thr
->executing ())
7424 /* If we have a pending event to process, skip resuming the
7425 target and go straight to processing it. */
7426 if (thr
->resumed () && thr
->has_pending_waitstatus ())
7430 /* Alright, we need to re-resume the target. If a thread was
7431 stepping, we need to restart it stepping. */
7432 if (restart_stepped_thread (proc_target
, minus_one_ptid
))
7435 /* Otherwise, find the first THREAD_RUNNING thread and resume
7437 for (thread_info
*thr
: all_threads (proc_target
))
7439 if (thr
->state
!= THREAD_RUNNING
)
7442 execution_control_state ecs
;
7443 reset_ecs (&ecs
, thr
);
7444 switch_to_thread (thr
);
7450 /* Set a previously stepped thread back to stepping. Returns true on
7451 success, false if the resume is not possible (e.g., the thread
7455 keep_going_stepped_thread (struct thread_info
*tp
)
7457 struct frame_info
*frame
;
7458 struct execution_control_state ecss
;
7459 struct execution_control_state
*ecs
= &ecss
;
7461 /* If the stepping thread exited, then don't try to switch back and
7462 resume it, which could fail in several different ways depending
7463 on the target. Instead, just keep going.
7465 We can find a stepping dead thread in the thread list in two
7468 - The target supports thread exit events, and when the target
7469 tries to delete the thread from the thread list, inferior_ptid
7470 pointed at the exiting thread. In such case, calling
7471 delete_thread does not really remove the thread from the list;
7472 instead, the thread is left listed, with 'exited' state.
7474 - The target's debug interface does not support thread exit
7475 events, and so we have no idea whatsoever if the previously
7476 stepping thread is still alive. For that reason, we need to
7477 synchronously query the target now. */
7479 if (tp
->state
== THREAD_EXITED
|| !target_thread_alive (tp
->ptid
))
7481 infrun_debug_printf ("not resuming previously stepped thread, it has "
7488 infrun_debug_printf ("resuming previously stepped thread");
7490 reset_ecs (ecs
, tp
);
7491 switch_to_thread (tp
);
7493 tp
->set_stop_pc (regcache_read_pc (get_thread_regcache (tp
)));
7494 frame
= get_current_frame ();
7496 /* If the PC of the thread we were trying to single-step has
7497 changed, then that thread has trapped or been signaled, but the
7498 event has not been reported to GDB yet. Re-poll the target
7499 looking for this particular thread's event (i.e. temporarily
7500 enable schedlock) by:
7502 - setting a break at the current PC
7503 - resuming that particular thread, only (by setting trap
7506 This prevents us continuously moving the single-step breakpoint
7507 forward, one instruction at a time, overstepping. */
7509 if (tp
->stop_pc () != tp
->prev_pc
)
7513 infrun_debug_printf ("expected thread advanced also (%s -> %s)",
7514 paddress (target_gdbarch (), tp
->prev_pc
),
7515 paddress (target_gdbarch (), tp
->stop_pc ()));
7517 /* Clear the info of the previous step-over, as it's no longer
7518 valid (if the thread was trying to step over a breakpoint, it
7519 has already succeeded). It's what keep_going would do too,
7520 if we called it. Do this before trying to insert the sss
7521 breakpoint, otherwise if we were previously trying to step
7522 over this exact address in another thread, the breakpoint is
7524 clear_step_over_info ();
7525 tp
->control
.trap_expected
= 0;
7527 insert_single_step_breakpoint (get_frame_arch (frame
),
7528 get_frame_address_space (frame
),
7531 tp
->set_resumed (true);
7532 resume_ptid
= internal_resume_ptid (tp
->control
.stepping_command
);
7533 do_target_resume (resume_ptid
, false, GDB_SIGNAL_0
);
7537 infrun_debug_printf ("expected thread still hasn't advanced");
7539 keep_going_pass_signal (ecs
);
7545 /* Is thread TP in the middle of (software or hardware)
7546 single-stepping? (Note the result of this function must never be
7547 passed directly as target_resume's STEP parameter.) */
7550 currently_stepping (struct thread_info
*tp
)
7552 return ((tp
->control
.step_range_end
7553 && tp
->control
.step_resume_breakpoint
== NULL
)
7554 || tp
->control
.trap_expected
7555 || tp
->stepped_breakpoint
7556 || bpstat_should_step ());
7559 /* Inferior has stepped into a subroutine call with source code that
7560 we should not step over. Do step to the first line of code in
7564 handle_step_into_function (struct gdbarch
*gdbarch
,
7565 struct execution_control_state
*ecs
)
7567 fill_in_stop_func (gdbarch
, ecs
);
7569 compunit_symtab
*cust
7570 = find_pc_compunit_symtab (ecs
->event_thread
->stop_pc ());
7571 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7572 ecs
->stop_func_start
7573 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7575 symtab_and_line stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7576 /* Use the step_resume_break to step until the end of the prologue,
7577 even if that involves jumps (as it seems to on the vax under
7579 /* If the prologue ends in the middle of a source line, continue to
7580 the end of that source line (if it is still within the function).
7581 Otherwise, just go to end of prologue. */
7582 if (stop_func_sal
.end
7583 && stop_func_sal
.pc
!= ecs
->stop_func_start
7584 && stop_func_sal
.end
< ecs
->stop_func_end
)
7585 ecs
->stop_func_start
= stop_func_sal
.end
;
7587 /* Architectures which require breakpoint adjustment might not be able
7588 to place a breakpoint at the computed address. If so, the test
7589 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7590 ecs->stop_func_start to an address at which a breakpoint may be
7591 legitimately placed.
7593 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7594 made, GDB will enter an infinite loop when stepping through
7595 optimized code consisting of VLIW instructions which contain
7596 subinstructions corresponding to different source lines. On
7597 FR-V, it's not permitted to place a breakpoint on any but the
7598 first subinstruction of a VLIW instruction. When a breakpoint is
7599 set, GDB will adjust the breakpoint address to the beginning of
7600 the VLIW instruction. Thus, we need to make the corresponding
7601 adjustment here when computing the stop address. */
7603 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
7605 ecs
->stop_func_start
7606 = gdbarch_adjust_breakpoint_address (gdbarch
,
7607 ecs
->stop_func_start
);
7610 if (ecs
->stop_func_start
== ecs
->event_thread
->stop_pc ())
7612 /* We are already there: stop now. */
7613 end_stepping_range (ecs
);
7618 /* Put the step-breakpoint there and go until there. */
7619 symtab_and_line sr_sal
;
7620 sr_sal
.pc
= ecs
->stop_func_start
;
7621 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
7622 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
7624 /* Do not specify what the fp should be when we stop since on
7625 some machines the prologue is where the new fp value is
7627 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
7629 /* And make sure stepping stops right away then. */
7630 ecs
->event_thread
->control
.step_range_end
7631 = ecs
->event_thread
->control
.step_range_start
;
7636 /* Inferior has stepped backward into a subroutine call with source
7637 code that we should not step over. Do step to the beginning of the
7638 last line of code in it. */
7641 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
7642 struct execution_control_state
*ecs
)
7644 struct compunit_symtab
*cust
;
7645 struct symtab_and_line stop_func_sal
;
7647 fill_in_stop_func (gdbarch
, ecs
);
7649 cust
= find_pc_compunit_symtab (ecs
->event_thread
->stop_pc ());
7650 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7651 ecs
->stop_func_start
7652 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7654 stop_func_sal
= find_pc_line (ecs
->event_thread
->stop_pc (), 0);
7656 /* OK, we're just going to keep stepping here. */
7657 if (stop_func_sal
.pc
== ecs
->event_thread
->stop_pc ())
7659 /* We're there already. Just stop stepping now. */
7660 end_stepping_range (ecs
);
7664 /* Else just reset the step range and keep going.
7665 No step-resume breakpoint, they don't work for
7666 epilogues, which can have multiple entry paths. */
7667 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
7668 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
7674 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7675 This is used to both functions and to skip over code. */
7678 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
7679 struct symtab_and_line sr_sal
,
7680 struct frame_id sr_id
,
7681 enum bptype sr_type
)
7683 /* There should never be more than one step-resume or longjmp-resume
7684 breakpoint per thread, so we should never be setting a new
7685 step_resume_breakpoint when one is already active. */
7686 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
7687 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
7689 infrun_debug_printf ("inserting step-resume breakpoint at %s",
7690 paddress (gdbarch
, sr_sal
.pc
));
7692 inferior_thread ()->control
.step_resume_breakpoint
7693 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
).release ();
7697 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
7698 struct symtab_and_line sr_sal
,
7699 struct frame_id sr_id
)
7701 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
7706 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7707 This is used to skip a potential signal handler.
7709 This is called with the interrupted function's frame. The signal
7710 handler, when it returns, will resume the interrupted function at
7714 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
7716 gdb_assert (return_frame
!= NULL
);
7718 struct gdbarch
*gdbarch
= get_frame_arch (return_frame
);
7720 symtab_and_line sr_sal
;
7721 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
7722 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7723 sr_sal
.pspace
= get_frame_program_space (return_frame
);
7725 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
7726 get_stack_frame_id (return_frame
),
7730 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7731 is used to skip a function after stepping into it (for "next" or if
7732 the called function has no debugging information).
7734 The current function has almost always been reached by single
7735 stepping a call or return instruction. NEXT_FRAME belongs to the
7736 current function, and the breakpoint will be set at the caller's
7739 This is a separate function rather than reusing
7740 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7741 get_prev_frame, which may stop prematurely (see the implementation
7742 of frame_unwind_caller_id for an example). */
7745 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
7747 /* We shouldn't have gotten here if we don't know where the call site
7749 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
7751 struct gdbarch
*gdbarch
= frame_unwind_caller_arch (next_frame
);
7753 symtab_and_line sr_sal
;
7754 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
7755 frame_unwind_caller_pc (next_frame
));
7756 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7757 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
7759 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
7760 frame_unwind_caller_id (next_frame
));
7763 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7764 new breakpoint at the target of a jmp_buf. The handling of
7765 longjmp-resume uses the same mechanisms used for handling
7766 "step-resume" breakpoints. */
7769 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
7771 /* There should never be more than one longjmp-resume breakpoint per
7772 thread, so we should never be setting a new
7773 longjmp_resume_breakpoint when one is already active. */
7774 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
7776 infrun_debug_printf ("inserting longjmp-resume breakpoint at %s",
7777 paddress (gdbarch
, pc
));
7779 inferior_thread ()->control
.exception_resume_breakpoint
=
7780 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
).release ();
7783 /* Insert an exception resume breakpoint. TP is the thread throwing
7784 the exception. The block B is the block of the unwinder debug hook
7785 function. FRAME is the frame corresponding to the call to this
7786 function. SYM is the symbol of the function argument holding the
7787 target PC of the exception. */
7790 insert_exception_resume_breakpoint (struct thread_info
*tp
,
7791 const struct block
*b
,
7792 struct frame_info
*frame
,
7797 struct block_symbol vsym
;
7798 struct value
*value
;
7800 struct breakpoint
*bp
;
7802 vsym
= lookup_symbol_search_name (sym
->search_name (),
7804 value
= read_var_value (vsym
.symbol
, vsym
.block
, frame
);
7805 /* If the value was optimized out, revert to the old behavior. */
7806 if (! value_optimized_out (value
))
7808 handler
= value_as_address (value
);
7810 infrun_debug_printf ("exception resume at %lx",
7811 (unsigned long) handler
);
7813 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7815 bp_exception_resume
).release ();
7817 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7820 bp
->thread
= tp
->global_num
;
7821 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7824 catch (const gdb_exception_error
&e
)
7826 /* We want to ignore errors here. */
7830 /* A helper for check_exception_resume that sets an
7831 exception-breakpoint based on a SystemTap probe. */
7834 insert_exception_resume_from_probe (struct thread_info
*tp
,
7835 const struct bound_probe
*probe
,
7836 struct frame_info
*frame
)
7838 struct value
*arg_value
;
7840 struct breakpoint
*bp
;
7842 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
7846 handler
= value_as_address (arg_value
);
7848 infrun_debug_printf ("exception resume at %s",
7849 paddress (probe
->objfile
->arch (), handler
));
7851 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7852 handler
, bp_exception_resume
).release ();
7853 bp
->thread
= tp
->global_num
;
7854 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7857 /* This is called when an exception has been intercepted. Check to
7858 see whether the exception's destination is of interest, and if so,
7859 set an exception resume breakpoint there. */
7862 check_exception_resume (struct execution_control_state
*ecs
,
7863 struct frame_info
*frame
)
7865 struct bound_probe probe
;
7866 struct symbol
*func
;
7868 /* First see if this exception unwinding breakpoint was set via a
7869 SystemTap probe point. If so, the probe has two arguments: the
7870 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7871 set a breakpoint there. */
7872 probe
= find_probe_by_pc (get_frame_pc (frame
));
7875 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
7879 func
= get_frame_function (frame
);
7885 const struct block
*b
;
7886 struct block_iterator iter
;
7890 /* The exception breakpoint is a thread-specific breakpoint on
7891 the unwinder's debug hook, declared as:
7893 void _Unwind_DebugHook (void *cfa, void *handler);
7895 The CFA argument indicates the frame to which control is
7896 about to be transferred. HANDLER is the destination PC.
7898 We ignore the CFA and set a temporary breakpoint at HANDLER.
7899 This is not extremely efficient but it avoids issues in gdb
7900 with computing the DWARF CFA, and it also works even in weird
7901 cases such as throwing an exception from inside a signal
7904 b
= SYMBOL_BLOCK_VALUE (func
);
7905 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
7907 if (!SYMBOL_IS_ARGUMENT (sym
))
7914 insert_exception_resume_breakpoint (ecs
->event_thread
,
7920 catch (const gdb_exception_error
&e
)
7926 stop_waiting (struct execution_control_state
*ecs
)
7928 infrun_debug_printf ("stop_waiting");
7930 /* Let callers know we don't want to wait for the inferior anymore. */
7931 ecs
->wait_some_more
= 0;
7933 /* If all-stop, but there exists a non-stop target, stop all
7934 threads now that we're presenting the stop to the user. */
7935 if (!non_stop
&& exists_non_stop_target ())
7936 stop_all_threads ();
7939 /* Like keep_going, but passes the signal to the inferior, even if the
7940 signal is set to nopass. */
7943 keep_going_pass_signal (struct execution_control_state
*ecs
)
7945 gdb_assert (ecs
->event_thread
->ptid
== inferior_ptid
);
7946 gdb_assert (!ecs
->event_thread
->resumed ());
7948 /* Save the pc before execution, to compare with pc after stop. */
7949 ecs
->event_thread
->prev_pc
7950 = regcache_read_pc_protected (get_thread_regcache (ecs
->event_thread
));
7952 if (ecs
->event_thread
->control
.trap_expected
)
7954 struct thread_info
*tp
= ecs
->event_thread
;
7956 infrun_debug_printf ("%s has trap_expected set, "
7957 "resuming to collect trap",
7958 target_pid_to_str (tp
->ptid
).c_str ());
7960 /* We haven't yet gotten our trap, and either: intercepted a
7961 non-signal event (e.g., a fork); or took a signal which we
7962 are supposed to pass through to the inferior. Simply
7964 resume (ecs
->event_thread
->stop_signal ());
7966 else if (step_over_info_valid_p ())
7968 /* Another thread is stepping over a breakpoint in-line. If
7969 this thread needs a step-over too, queue the request. In
7970 either case, this resume must be deferred for later. */
7971 struct thread_info
*tp
= ecs
->event_thread
;
7973 if (ecs
->hit_singlestep_breakpoint
7974 || thread_still_needs_step_over (tp
))
7976 infrun_debug_printf ("step-over already in progress: "
7977 "step-over for %s deferred",
7978 target_pid_to_str (tp
->ptid
).c_str ());
7979 global_thread_step_over_chain_enqueue (tp
);
7983 infrun_debug_printf ("step-over in progress: resume of %s deferred",
7984 target_pid_to_str (tp
->ptid
).c_str ());
7989 struct regcache
*regcache
= get_current_regcache ();
7992 step_over_what step_what
;
7994 /* Either the trap was not expected, but we are continuing
7995 anyway (if we got a signal, the user asked it be passed to
7998 We got our expected trap, but decided we should resume from
8001 We're going to run this baby now!
8003 Note that insert_breakpoints won't try to re-insert
8004 already inserted breakpoints. Therefore, we don't
8005 care if breakpoints were already inserted, or not. */
8007 /* If we need to step over a breakpoint, and we're not using
8008 displaced stepping to do so, insert all breakpoints
8009 (watchpoints, etc.) but the one we're stepping over, step one
8010 instruction, and then re-insert the breakpoint when that step
8013 step_what
= thread_still_needs_step_over (ecs
->event_thread
);
8015 remove_bp
= (ecs
->hit_singlestep_breakpoint
8016 || (step_what
& STEP_OVER_BREAKPOINT
));
8017 remove_wps
= (step_what
& STEP_OVER_WATCHPOINT
);
8019 /* We can't use displaced stepping if we need to step past a
8020 watchpoint. The instruction copied to the scratch pad would
8021 still trigger the watchpoint. */
8023 && (remove_wps
|| !use_displaced_stepping (ecs
->event_thread
)))
8025 set_step_over_info (regcache
->aspace (),
8026 regcache_read_pc (regcache
), remove_wps
,
8027 ecs
->event_thread
->global_num
);
8029 else if (remove_wps
)
8030 set_step_over_info (NULL
, 0, remove_wps
, -1);
8032 /* If we now need to do an in-line step-over, we need to stop
8033 all other threads. Note this must be done before
8034 insert_breakpoints below, because that removes the breakpoint
8035 we're about to step over, otherwise other threads could miss
8037 if (step_over_info_valid_p () && target_is_non_stop_p ())
8038 stop_all_threads ();
8040 /* Stop stepping if inserting breakpoints fails. */
8043 insert_breakpoints ();
8045 catch (const gdb_exception_error
&e
)
8047 exception_print (gdb_stderr
, e
);
8049 clear_step_over_info ();
8053 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
8055 resume (ecs
->event_thread
->stop_signal ());
8058 prepare_to_wait (ecs
);
8061 /* Called when we should continue running the inferior, because the
8062 current event doesn't cause a user visible stop. This does the
8063 resuming part; waiting for the next event is done elsewhere. */
8066 keep_going (struct execution_control_state
*ecs
)
8068 if (ecs
->event_thread
->control
.trap_expected
8069 && ecs
->event_thread
->stop_signal () == GDB_SIGNAL_TRAP
)
8070 ecs
->event_thread
->control
.trap_expected
= 0;
8072 if (!signal_program
[ecs
->event_thread
->stop_signal ()])
8073 ecs
->event_thread
->set_stop_signal (GDB_SIGNAL_0
);
8074 keep_going_pass_signal (ecs
);
8077 /* This function normally comes after a resume, before
8078 handle_inferior_event exits. It takes care of any last bits of
8079 housekeeping, and sets the all-important wait_some_more flag. */
8082 prepare_to_wait (struct execution_control_state
*ecs
)
8084 infrun_debug_printf ("prepare_to_wait");
8086 ecs
->wait_some_more
= 1;
8088 /* If the target can't async, emulate it by marking the infrun event
8089 handler such that as soon as we get back to the event-loop, we
8090 immediately end up in fetch_inferior_event again calling
8092 if (!target_can_async_p ())
8093 mark_infrun_async_event_handler ();
8096 /* We are done with the step range of a step/next/si/ni command.
8097 Called once for each n of a "step n" operation. */
8100 end_stepping_range (struct execution_control_state
*ecs
)
8102 ecs
->event_thread
->control
.stop_step
= 1;
8106 /* Several print_*_reason functions to print why the inferior has stopped.
8107 We always print something when the inferior exits, or receives a signal.
8108 The rest of the cases are dealt with later on in normal_stop and
8109 print_it_typical. Ideally there should be a call to one of these
8110 print_*_reason functions functions from handle_inferior_event each time
8111 stop_waiting is called.
8113 Note that we don't call these directly, instead we delegate that to
8114 the interpreters, through observers. Interpreters then call these
8115 with whatever uiout is right. */
8118 print_end_stepping_range_reason (struct ui_out
*uiout
)
8120 /* For CLI-like interpreters, print nothing. */
8122 if (uiout
->is_mi_like_p ())
8124 uiout
->field_string ("reason",
8125 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
8130 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
8132 annotate_signalled ();
8133 if (uiout
->is_mi_like_p ())
8135 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
8136 uiout
->text ("\nProgram terminated with signal ");
8137 annotate_signal_name ();
8138 uiout
->field_string ("signal-name",
8139 gdb_signal_to_name (siggnal
));
8140 annotate_signal_name_end ();
8142 annotate_signal_string ();
8143 uiout
->field_string ("signal-meaning",
8144 gdb_signal_to_string (siggnal
));
8145 annotate_signal_string_end ();
8146 uiout
->text (".\n");
8147 uiout
->text ("The program no longer exists.\n");
8151 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
8153 struct inferior
*inf
= current_inferior ();
8154 std::string pidstr
= target_pid_to_str (ptid_t (inf
->pid
));
8156 annotate_exited (exitstatus
);
8159 if (uiout
->is_mi_like_p ())
8160 uiout
->field_string ("reason", async_reason_lookup (EXEC_ASYNC_EXITED
));
8161 std::string exit_code_str
8162 = string_printf ("0%o", (unsigned int) exitstatus
);
8163 uiout
->message ("[Inferior %s (%s) exited with code %pF]\n",
8164 plongest (inf
->num
), pidstr
.c_str (),
8165 string_field ("exit-code", exit_code_str
.c_str ()));
8169 if (uiout
->is_mi_like_p ())
8171 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
8172 uiout
->message ("[Inferior %s (%s) exited normally]\n",
8173 plongest (inf
->num
), pidstr
.c_str ());
8178 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
8180 struct thread_info
*thr
= inferior_thread ();
8184 if (uiout
->is_mi_like_p ())
8186 else if (show_thread_that_caused_stop ())
8190 uiout
->text ("\nThread ");
8191 uiout
->field_string ("thread-id", print_thread_id (thr
));
8193 name
= thr
->name
!= NULL
? thr
->name
: target_thread_name (thr
);
8196 uiout
->text (" \"");
8197 uiout
->field_string ("name", name
);
8202 uiout
->text ("\nProgram");
8204 if (siggnal
== GDB_SIGNAL_0
&& !uiout
->is_mi_like_p ())
8205 uiout
->text (" stopped");
8208 uiout
->text (" received signal ");
8209 annotate_signal_name ();
8210 if (uiout
->is_mi_like_p ())
8212 ("reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
8213 uiout
->field_string ("signal-name", gdb_signal_to_name (siggnal
));
8214 annotate_signal_name_end ();
8216 annotate_signal_string ();
8217 uiout
->field_string ("signal-meaning", gdb_signal_to_string (siggnal
));
8219 struct regcache
*regcache
= get_current_regcache ();
8220 struct gdbarch
*gdbarch
= regcache
->arch ();
8221 if (gdbarch_report_signal_info_p (gdbarch
))
8222 gdbarch_report_signal_info (gdbarch
, uiout
, siggnal
);
8224 annotate_signal_string_end ();
8226 uiout
->text (".\n");
8230 print_no_history_reason (struct ui_out
*uiout
)
8232 uiout
->text ("\nNo more reverse-execution history.\n");
8235 /* Print current location without a level number, if we have changed
8236 functions or hit a breakpoint. Print source line if we have one.
8237 bpstat_print contains the logic deciding in detail what to print,
8238 based on the event(s) that just occurred. */
8241 print_stop_location (struct target_waitstatus
*ws
)
8244 enum print_what source_flag
;
8245 int do_frame_printing
= 1;
8246 struct thread_info
*tp
= inferior_thread ();
8248 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
8252 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
8253 should) carry around the function and does (or should) use
8254 that when doing a frame comparison. */
8255 if (tp
->control
.stop_step
8256 && frame_id_eq (tp
->control
.step_frame_id
,
8257 get_frame_id (get_current_frame ()))
8258 && (tp
->control
.step_start_function
8259 == find_pc_function (tp
->stop_pc ())))
8261 /* Finished step, just print source line. */
8262 source_flag
= SRC_LINE
;
8266 /* Print location and source line. */
8267 source_flag
= SRC_AND_LOC
;
8270 case PRINT_SRC_AND_LOC
:
8271 /* Print location and source line. */
8272 source_flag
= SRC_AND_LOC
;
8274 case PRINT_SRC_ONLY
:
8275 source_flag
= SRC_LINE
;
8278 /* Something bogus. */
8279 source_flag
= SRC_LINE
;
8280 do_frame_printing
= 0;
8283 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
8286 /* The behavior of this routine with respect to the source
8288 SRC_LINE: Print only source line
8289 LOCATION: Print only location
8290 SRC_AND_LOC: Print location and source line. */
8291 if (do_frame_printing
)
8292 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
8298 print_stop_event (struct ui_out
*uiout
, bool displays
)
8300 struct target_waitstatus last
;
8301 struct thread_info
*tp
;
8303 get_last_target_status (nullptr, nullptr, &last
);
8306 scoped_restore save_uiout
= make_scoped_restore (¤t_uiout
, uiout
);
8308 print_stop_location (&last
);
8310 /* Display the auto-display expressions. */
8315 tp
= inferior_thread ();
8316 if (tp
->thread_fsm
!= NULL
8317 && tp
->thread_fsm
->finished_p ())
8319 struct return_value_info
*rv
;
8321 rv
= tp
->thread_fsm
->return_value ();
8323 print_return_value (uiout
, rv
);
8330 maybe_remove_breakpoints (void)
8332 if (!breakpoints_should_be_inserted_now () && target_has_execution ())
8334 if (remove_breakpoints ())
8336 target_terminal::ours_for_output ();
8337 printf_filtered (_("Cannot remove breakpoints because "
8338 "program is no longer writable.\nFurther "
8339 "execution is probably impossible.\n"));
8344 /* The execution context that just caused a normal stop. */
8350 DISABLE_COPY_AND_ASSIGN (stop_context
);
8352 bool changed () const;
8357 /* The event PTID. */
8361 /* If stopp for a thread event, this is the thread that caused the
8363 thread_info_ref thread
;
8365 /* The inferior that caused the stop. */
8369 /* Initializes a new stop context. If stopped for a thread event, this
8370 takes a strong reference to the thread. */
8372 stop_context::stop_context ()
8374 stop_id
= get_stop_id ();
8375 ptid
= inferior_ptid
;
8376 inf_num
= current_inferior ()->num
;
8378 if (inferior_ptid
!= null_ptid
)
8380 /* Take a strong reference so that the thread can't be deleted
8382 thread
= thread_info_ref::new_reference (inferior_thread ());
8386 /* Return true if the current context no longer matches the saved stop
8390 stop_context::changed () const
8392 if (ptid
!= inferior_ptid
)
8394 if (inf_num
!= current_inferior ()->num
)
8396 if (thread
!= NULL
&& thread
->state
!= THREAD_STOPPED
)
8398 if (get_stop_id () != stop_id
)
8408 struct target_waitstatus last
;
8410 get_last_target_status (nullptr, nullptr, &last
);
8414 /* If an exception is thrown from this point on, make sure to
8415 propagate GDB's knowledge of the executing state to the
8416 frontend/user running state. A QUIT is an easy exception to see
8417 here, so do this before any filtered output. */
8419 ptid_t finish_ptid
= null_ptid
;
8422 finish_ptid
= minus_one_ptid
;
8423 else if (last
.kind
== TARGET_WAITKIND_SIGNALLED
8424 || last
.kind
== TARGET_WAITKIND_EXITED
)
8426 /* On some targets, we may still have live threads in the
8427 inferior when we get a process exit event. E.g., for
8428 "checkpoint", when the current checkpoint/fork exits,
8429 linux-fork.c automatically switches to another fork from
8430 within target_mourn_inferior. */
8431 if (inferior_ptid
!= null_ptid
)
8432 finish_ptid
= ptid_t (inferior_ptid
.pid ());
8434 else if (last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8435 finish_ptid
= inferior_ptid
;
8437 gdb::optional
<scoped_finish_thread_state
> maybe_finish_thread_state
;
8438 if (finish_ptid
!= null_ptid
)
8440 maybe_finish_thread_state
.emplace
8441 (user_visible_resume_target (finish_ptid
), finish_ptid
);
8444 /* As we're presenting a stop, and potentially removing breakpoints,
8445 update the thread list so we can tell whether there are threads
8446 running on the target. With target remote, for example, we can
8447 only learn about new threads when we explicitly update the thread
8448 list. Do this before notifying the interpreters about signal
8449 stops, end of stepping ranges, etc., so that the "new thread"
8450 output is emitted before e.g., "Program received signal FOO",
8451 instead of after. */
8452 update_thread_list ();
8454 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
8455 gdb::observers::signal_received
.notify (inferior_thread ()->stop_signal ());
8457 /* As with the notification of thread events, we want to delay
8458 notifying the user that we've switched thread context until
8459 the inferior actually stops.
8461 There's no point in saying anything if the inferior has exited.
8462 Note that SIGNALLED here means "exited with a signal", not
8463 "received a signal".
8465 Also skip saying anything in non-stop mode. In that mode, as we
8466 don't want GDB to switch threads behind the user's back, to avoid
8467 races where the user is typing a command to apply to thread x,
8468 but GDB switches to thread y before the user finishes entering
8469 the command, fetch_inferior_event installs a cleanup to restore
8470 the current thread back to the thread the user had selected right
8471 after this event is handled, so we're not really switching, only
8472 informing of a stop. */
8474 && previous_inferior_ptid
!= inferior_ptid
8475 && target_has_execution ()
8476 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
8477 && last
.kind
!= TARGET_WAITKIND_EXITED
8478 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8480 SWITCH_THRU_ALL_UIS ()
8482 target_terminal::ours_for_output ();
8483 printf_filtered (_("[Switching to %s]\n"),
8484 target_pid_to_str (inferior_ptid
).c_str ());
8485 annotate_thread_changed ();
8487 previous_inferior_ptid
= inferior_ptid
;
8490 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
8492 SWITCH_THRU_ALL_UIS ()
8493 if (current_ui
->prompt_state
== PROMPT_BLOCKED
)
8495 target_terminal::ours_for_output ();
8496 printf_filtered (_("No unwaited-for children left.\n"));
8500 /* Note: this depends on the update_thread_list call above. */
8501 maybe_remove_breakpoints ();
8503 /* If an auto-display called a function and that got a signal,
8504 delete that auto-display to avoid an infinite recursion. */
8506 if (stopped_by_random_signal
)
8507 disable_current_display ();
8509 SWITCH_THRU_ALL_UIS ()
8511 async_enable_stdin ();
8514 /* Let the user/frontend see the threads as stopped. */
8515 maybe_finish_thread_state
.reset ();
8517 /* Select innermost stack frame - i.e., current frame is frame 0,
8518 and current location is based on that. Handle the case where the
8519 dummy call is returning after being stopped. E.g. the dummy call
8520 previously hit a breakpoint. (If the dummy call returns
8521 normally, we won't reach here.) Do this before the stop hook is
8522 run, so that it doesn't get to see the temporary dummy frame,
8523 which is not where we'll present the stop. */
8524 if (has_stack_frames ())
8526 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
8528 /* Pop the empty frame that contains the stack dummy. This
8529 also restores inferior state prior to the call (struct
8530 infcall_suspend_state). */
8531 struct frame_info
*frame
= get_current_frame ();
8533 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
8535 /* frame_pop calls reinit_frame_cache as the last thing it
8536 does which means there's now no selected frame. */
8539 select_frame (get_current_frame ());
8541 /* Set the current source location. */
8542 set_current_sal_from_frame (get_current_frame ());
8545 /* Look up the hook_stop and run it (CLI internally handles problem
8546 of stop_command's pre-hook not existing). */
8547 if (stop_command
!= NULL
)
8549 stop_context saved_context
;
8553 execute_cmd_pre_hook (stop_command
);
8555 catch (const gdb_exception
&ex
)
8557 exception_fprintf (gdb_stderr
, ex
,
8558 "Error while running hook_stop:\n");
8561 /* If the stop hook resumes the target, then there's no point in
8562 trying to notify about the previous stop; its context is
8563 gone. Likewise if the command switches thread or inferior --
8564 the observers would print a stop for the wrong
8566 if (saved_context
.changed ())
8570 /* Notify observers about the stop. This is where the interpreters
8571 print the stop event. */
8572 if (inferior_ptid
!= null_ptid
)
8573 gdb::observers::normal_stop
.notify (inferior_thread ()->control
.stop_bpstat
,
8576 gdb::observers::normal_stop
.notify (NULL
, stop_print_frame
);
8578 annotate_stopped ();
8580 if (target_has_execution ())
8582 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
8583 && last
.kind
!= TARGET_WAITKIND_EXITED
8584 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8585 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8586 Delete any breakpoint that is to be deleted at the next stop. */
8587 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
8590 /* Try to get rid of automatically added inferiors that are no
8591 longer needed. Keeping those around slows down things linearly.
8592 Note that this never removes the current inferior. */
8599 signal_stop_state (int signo
)
8601 return signal_stop
[signo
];
8605 signal_print_state (int signo
)
8607 return signal_print
[signo
];
8611 signal_pass_state (int signo
)
8613 return signal_program
[signo
];
8617 signal_cache_update (int signo
)
8621 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
8622 signal_cache_update (signo
);
8627 signal_pass
[signo
] = (signal_stop
[signo
] == 0
8628 && signal_print
[signo
] == 0
8629 && signal_program
[signo
] == 1
8630 && signal_catch
[signo
] == 0);
8634 signal_stop_update (int signo
, int state
)
8636 int ret
= signal_stop
[signo
];
8638 signal_stop
[signo
] = state
;
8639 signal_cache_update (signo
);
8644 signal_print_update (int signo
, int state
)
8646 int ret
= signal_print
[signo
];
8648 signal_print
[signo
] = state
;
8649 signal_cache_update (signo
);
8654 signal_pass_update (int signo
, int state
)
8656 int ret
= signal_program
[signo
];
8658 signal_program
[signo
] = state
;
8659 signal_cache_update (signo
);
8663 /* Update the global 'signal_catch' from INFO and notify the
8667 signal_catch_update (const unsigned int *info
)
8671 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
8672 signal_catch
[i
] = info
[i
] > 0;
8673 signal_cache_update (-1);
8674 target_pass_signals (signal_pass
);
8678 sig_print_header (void)
8680 printf_filtered (_("Signal Stop\tPrint\tPass "
8681 "to program\tDescription\n"));
8685 sig_print_info (enum gdb_signal oursig
)
8687 const char *name
= gdb_signal_to_name (oursig
);
8688 int name_padding
= 13 - strlen (name
);
8690 if (name_padding
<= 0)
8693 printf_filtered ("%s", name
);
8694 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
8695 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
8696 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
8697 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
8698 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
8701 /* Specify how various signals in the inferior should be handled. */
8704 handle_command (const char *args
, int from_tty
)
8706 int digits
, wordlen
;
8707 int sigfirst
, siglast
;
8708 enum gdb_signal oursig
;
8713 error_no_arg (_("signal to handle"));
8716 /* Allocate and zero an array of flags for which signals to handle. */
8718 const size_t nsigs
= GDB_SIGNAL_LAST
;
8719 unsigned char sigs
[nsigs
] {};
8721 /* Break the command line up into args. */
8723 gdb_argv
built_argv (args
);
8725 /* Walk through the args, looking for signal oursigs, signal names, and
8726 actions. Signal numbers and signal names may be interspersed with
8727 actions, with the actions being performed for all signals cumulatively
8728 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8730 for (char *arg
: built_argv
)
8732 wordlen
= strlen (arg
);
8733 for (digits
= 0; isdigit (arg
[digits
]); digits
++)
8737 sigfirst
= siglast
= -1;
8739 if (wordlen
>= 1 && !strncmp (arg
, "all", wordlen
))
8741 /* Apply action to all signals except those used by the
8742 debugger. Silently skip those. */
8745 siglast
= nsigs
- 1;
8747 else if (wordlen
>= 1 && !strncmp (arg
, "stop", wordlen
))
8749 SET_SIGS (nsigs
, sigs
, signal_stop
);
8750 SET_SIGS (nsigs
, sigs
, signal_print
);
8752 else if (wordlen
>= 1 && !strncmp (arg
, "ignore", wordlen
))
8754 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8756 else if (wordlen
>= 2 && !strncmp (arg
, "print", wordlen
))
8758 SET_SIGS (nsigs
, sigs
, signal_print
);
8760 else if (wordlen
>= 2 && !strncmp (arg
, "pass", wordlen
))
8762 SET_SIGS (nsigs
, sigs
, signal_program
);
8764 else if (wordlen
>= 3 && !strncmp (arg
, "nostop", wordlen
))
8766 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8768 else if (wordlen
>= 3 && !strncmp (arg
, "noignore", wordlen
))
8770 SET_SIGS (nsigs
, sigs
, signal_program
);
8772 else if (wordlen
>= 4 && !strncmp (arg
, "noprint", wordlen
))
8774 UNSET_SIGS (nsigs
, sigs
, signal_print
);
8775 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8777 else if (wordlen
>= 4 && !strncmp (arg
, "nopass", wordlen
))
8779 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8781 else if (digits
> 0)
8783 /* It is numeric. The numeric signal refers to our own
8784 internal signal numbering from target.h, not to host/target
8785 signal number. This is a feature; users really should be
8786 using symbolic names anyway, and the common ones like
8787 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8789 sigfirst
= siglast
= (int)
8790 gdb_signal_from_command (atoi (arg
));
8791 if (arg
[digits
] == '-')
8794 gdb_signal_from_command (atoi (arg
+ digits
+ 1));
8796 if (sigfirst
> siglast
)
8798 /* Bet he didn't figure we'd think of this case... */
8799 std::swap (sigfirst
, siglast
);
8804 oursig
= gdb_signal_from_name (arg
);
8805 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
8807 sigfirst
= siglast
= (int) oursig
;
8811 /* Not a number and not a recognized flag word => complain. */
8812 error (_("Unrecognized or ambiguous flag word: \"%s\"."), arg
);
8816 /* If any signal numbers or symbol names were found, set flags for
8817 which signals to apply actions to. */
8819 for (int signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
8821 switch ((enum gdb_signal
) signum
)
8823 case GDB_SIGNAL_TRAP
:
8824 case GDB_SIGNAL_INT
:
8825 if (!allsigs
&& !sigs
[signum
])
8827 if (query (_("%s is used by the debugger.\n\
8828 Are you sure you want to change it? "),
8829 gdb_signal_to_name ((enum gdb_signal
) signum
)))
8834 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8838 case GDB_SIGNAL_DEFAULT
:
8839 case GDB_SIGNAL_UNKNOWN
:
8840 /* Make sure that "all" doesn't print these. */
8849 for (int signum
= 0; signum
< nsigs
; signum
++)
8852 signal_cache_update (-1);
8853 target_pass_signals (signal_pass
);
8854 target_program_signals (signal_program
);
8858 /* Show the results. */
8859 sig_print_header ();
8860 for (; signum
< nsigs
; signum
++)
8862 sig_print_info ((enum gdb_signal
) signum
);
8869 /* Complete the "handle" command. */
8872 handle_completer (struct cmd_list_element
*ignore
,
8873 completion_tracker
&tracker
,
8874 const char *text
, const char *word
)
8876 static const char * const keywords
[] =
8890 signal_completer (ignore
, tracker
, text
, word
);
8891 complete_on_enum (tracker
, keywords
, word
, word
);
8895 gdb_signal_from_command (int num
)
8897 if (num
>= 1 && num
<= 15)
8898 return (enum gdb_signal
) num
;
8899 error (_("Only signals 1-15 are valid as numeric signals.\n\
8900 Use \"info signals\" for a list of symbolic signals."));
8903 /* Print current contents of the tables set by the handle command.
8904 It is possible we should just be printing signals actually used
8905 by the current target (but for things to work right when switching
8906 targets, all signals should be in the signal tables). */
8909 info_signals_command (const char *signum_exp
, int from_tty
)
8911 enum gdb_signal oursig
;
8913 sig_print_header ();
8917 /* First see if this is a symbol name. */
8918 oursig
= gdb_signal_from_name (signum_exp
);
8919 if (oursig
== GDB_SIGNAL_UNKNOWN
)
8921 /* No, try numeric. */
8923 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
8925 sig_print_info (oursig
);
8929 printf_filtered ("\n");
8930 /* These ugly casts brought to you by the native VAX compiler. */
8931 for (oursig
= GDB_SIGNAL_FIRST
;
8932 (int) oursig
< (int) GDB_SIGNAL_LAST
;
8933 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
8937 if (oursig
!= GDB_SIGNAL_UNKNOWN
8938 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
8939 sig_print_info (oursig
);
8942 printf_filtered (_("\nUse the \"handle\" command "
8943 "to change these tables.\n"));
8946 /* The $_siginfo convenience variable is a bit special. We don't know
8947 for sure the type of the value until we actually have a chance to
8948 fetch the data. The type can change depending on gdbarch, so it is
8949 also dependent on which thread you have selected.
8951 1. making $_siginfo be an internalvar that creates a new value on
8954 2. making the value of $_siginfo be an lval_computed value. */
8956 /* This function implements the lval_computed support for reading a
8960 siginfo_value_read (struct value
*v
)
8962 LONGEST transferred
;
8964 /* If we can access registers, so can we access $_siginfo. Likewise
8966 validate_registers_access ();
8969 target_read (current_inferior ()->top_target (),
8970 TARGET_OBJECT_SIGNAL_INFO
,
8972 value_contents_all_raw (v
),
8974 TYPE_LENGTH (value_type (v
)));
8976 if (transferred
!= TYPE_LENGTH (value_type (v
)))
8977 error (_("Unable to read siginfo"));
8980 /* This function implements the lval_computed support for writing a
8984 siginfo_value_write (struct value
*v
, struct value
*fromval
)
8986 LONGEST transferred
;
8988 /* If we can access registers, so can we access $_siginfo. Likewise
8990 validate_registers_access ();
8992 transferred
= target_write (current_inferior ()->top_target (),
8993 TARGET_OBJECT_SIGNAL_INFO
,
8995 value_contents_all_raw (fromval
),
8997 TYPE_LENGTH (value_type (fromval
)));
8999 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
9000 error (_("Unable to write siginfo"));
9003 static const struct lval_funcs siginfo_value_funcs
=
9009 /* Return a new value with the correct type for the siginfo object of
9010 the current thread using architecture GDBARCH. Return a void value
9011 if there's no object available. */
9013 static struct value
*
9014 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
9017 if (target_has_stack ()
9018 && inferior_ptid
!= null_ptid
9019 && gdbarch_get_siginfo_type_p (gdbarch
))
9021 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
9023 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
9026 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
9030 /* infcall_suspend_state contains state about the program itself like its
9031 registers and any signal it received when it last stopped.
9032 This state must be restored regardless of how the inferior function call
9033 ends (either successfully, or after it hits a breakpoint or signal)
9034 if the program is to properly continue where it left off. */
9036 class infcall_suspend_state
9039 /* Capture state from GDBARCH, TP, and REGCACHE that must be restored
9040 once the inferior function call has finished. */
9041 infcall_suspend_state (struct gdbarch
*gdbarch
,
9042 const struct thread_info
*tp
,
9043 struct regcache
*regcache
)
9044 : m_registers (new readonly_detached_regcache (*regcache
))
9046 tp
->save_suspend_to (m_thread_suspend
);
9048 gdb::unique_xmalloc_ptr
<gdb_byte
> siginfo_data
;
9050 if (gdbarch_get_siginfo_type_p (gdbarch
))
9052 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
9053 size_t len
= TYPE_LENGTH (type
);
9055 siginfo_data
.reset ((gdb_byte
*) xmalloc (len
));
9057 if (target_read (current_inferior ()->top_target (),
9058 TARGET_OBJECT_SIGNAL_INFO
, NULL
,
9059 siginfo_data
.get (), 0, len
) != len
)
9061 /* Errors ignored. */
9062 siginfo_data
.reset (nullptr);
9068 m_siginfo_gdbarch
= gdbarch
;
9069 m_siginfo_data
= std::move (siginfo_data
);
9073 /* Return a pointer to the stored register state. */
9075 readonly_detached_regcache
*registers () const
9077 return m_registers
.get ();
9080 /* Restores the stored state into GDBARCH, TP, and REGCACHE. */
9082 void restore (struct gdbarch
*gdbarch
,
9083 struct thread_info
*tp
,
9084 struct regcache
*regcache
) const
9086 tp
->restore_suspend_from (m_thread_suspend
);
9088 if (m_siginfo_gdbarch
== gdbarch
)
9090 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
9092 /* Errors ignored. */
9093 target_write (current_inferior ()->top_target (),
9094 TARGET_OBJECT_SIGNAL_INFO
, NULL
,
9095 m_siginfo_data
.get (), 0, TYPE_LENGTH (type
));
9098 /* The inferior can be gone if the user types "print exit(0)"
9099 (and perhaps other times). */
9100 if (target_has_execution ())
9101 /* NB: The register write goes through to the target. */
9102 regcache
->restore (registers ());
9106 /* How the current thread stopped before the inferior function call was
9108 struct thread_suspend_state m_thread_suspend
;
9110 /* The registers before the inferior function call was executed. */
9111 std::unique_ptr
<readonly_detached_regcache
> m_registers
;
9113 /* Format of SIGINFO_DATA or NULL if it is not present. */
9114 struct gdbarch
*m_siginfo_gdbarch
= nullptr;
9116 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
9117 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
9118 content would be invalid. */
9119 gdb::unique_xmalloc_ptr
<gdb_byte
> m_siginfo_data
;
9122 infcall_suspend_state_up
9123 save_infcall_suspend_state ()
9125 struct thread_info
*tp
= inferior_thread ();
9126 struct regcache
*regcache
= get_current_regcache ();
9127 struct gdbarch
*gdbarch
= regcache
->arch ();
9129 infcall_suspend_state_up inf_state
9130 (new struct infcall_suspend_state (gdbarch
, tp
, regcache
));
9132 /* Having saved the current state, adjust the thread state, discarding
9133 any stop signal information. The stop signal is not useful when
9134 starting an inferior function call, and run_inferior_call will not use
9135 the signal due to its `proceed' call with GDB_SIGNAL_0. */
9136 tp
->set_stop_signal (GDB_SIGNAL_0
);
9141 /* Restore inferior session state to INF_STATE. */
9144 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
9146 struct thread_info
*tp
= inferior_thread ();
9147 struct regcache
*regcache
= get_current_regcache ();
9148 struct gdbarch
*gdbarch
= regcache
->arch ();
9150 inf_state
->restore (gdbarch
, tp
, regcache
);
9151 discard_infcall_suspend_state (inf_state
);
9155 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
9160 readonly_detached_regcache
*
9161 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
9163 return inf_state
->registers ();
9166 /* infcall_control_state contains state regarding gdb's control of the
9167 inferior itself like stepping control. It also contains session state like
9168 the user's currently selected frame. */
9170 struct infcall_control_state
9172 struct thread_control_state thread_control
;
9173 struct inferior_control_state inferior_control
;
9176 enum stop_stack_kind stop_stack_dummy
= STOP_NONE
;
9177 int stopped_by_random_signal
= 0;
9179 /* ID and level of the selected frame when the inferior function
9181 struct frame_id selected_frame_id
{};
9182 int selected_frame_level
= -1;
9185 /* Save all of the information associated with the inferior<==>gdb
9188 infcall_control_state_up
9189 save_infcall_control_state ()
9191 infcall_control_state_up
inf_status (new struct infcall_control_state
);
9192 struct thread_info
*tp
= inferior_thread ();
9193 struct inferior
*inf
= current_inferior ();
9195 inf_status
->thread_control
= tp
->control
;
9196 inf_status
->inferior_control
= inf
->control
;
9198 tp
->control
.step_resume_breakpoint
= NULL
;
9199 tp
->control
.exception_resume_breakpoint
= NULL
;
9201 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
9202 chain. If caller's caller is walking the chain, they'll be happier if we
9203 hand them back the original chain when restore_infcall_control_state is
9205 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
9208 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
9209 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
9211 save_selected_frame (&inf_status
->selected_frame_id
,
9212 &inf_status
->selected_frame_level
);
9217 /* Restore inferior session state to INF_STATUS. */
9220 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
9222 struct thread_info
*tp
= inferior_thread ();
9223 struct inferior
*inf
= current_inferior ();
9225 if (tp
->control
.step_resume_breakpoint
)
9226 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
9228 if (tp
->control
.exception_resume_breakpoint
)
9229 tp
->control
.exception_resume_breakpoint
->disposition
9230 = disp_del_at_next_stop
;
9232 /* Handle the bpstat_copy of the chain. */
9233 bpstat_clear (&tp
->control
.stop_bpstat
);
9235 tp
->control
= inf_status
->thread_control
;
9236 inf
->control
= inf_status
->inferior_control
;
9239 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
9240 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
9242 if (target_has_stack ())
9244 restore_selected_frame (inf_status
->selected_frame_id
,
9245 inf_status
->selected_frame_level
);
9252 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
9254 if (inf_status
->thread_control
.step_resume_breakpoint
)
9255 inf_status
->thread_control
.step_resume_breakpoint
->disposition
9256 = disp_del_at_next_stop
;
9258 if (inf_status
->thread_control
.exception_resume_breakpoint
)
9259 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
9260 = disp_del_at_next_stop
;
9262 /* See save_infcall_control_state for info on stop_bpstat. */
9263 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
9271 clear_exit_convenience_vars (void)
9273 clear_internalvar (lookup_internalvar ("_exitsignal"));
9274 clear_internalvar (lookup_internalvar ("_exitcode"));
9278 /* User interface for reverse debugging:
9279 Set exec-direction / show exec-direction commands
9280 (returns error unless target implements to_set_exec_direction method). */
9282 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
9283 static const char exec_forward
[] = "forward";
9284 static const char exec_reverse
[] = "reverse";
9285 static const char *exec_direction
= exec_forward
;
9286 static const char *const exec_direction_names
[] = {
9293 set_exec_direction_func (const char *args
, int from_tty
,
9294 struct cmd_list_element
*cmd
)
9296 if (target_can_execute_reverse ())
9298 if (!strcmp (exec_direction
, exec_forward
))
9299 execution_direction
= EXEC_FORWARD
;
9300 else if (!strcmp (exec_direction
, exec_reverse
))
9301 execution_direction
= EXEC_REVERSE
;
9305 exec_direction
= exec_forward
;
9306 error (_("Target does not support this operation."));
9311 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
9312 struct cmd_list_element
*cmd
, const char *value
)
9314 switch (execution_direction
) {
9316 fprintf_filtered (out
, _("Forward.\n"));
9319 fprintf_filtered (out
, _("Reverse.\n"));
9322 internal_error (__FILE__
, __LINE__
,
9323 _("bogus execution_direction value: %d"),
9324 (int) execution_direction
);
9329 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
9330 struct cmd_list_element
*c
, const char *value
)
9332 fprintf_filtered (file
, _("Resuming the execution of threads "
9333 "of all processes is %s.\n"), value
);
9336 /* Implementation of `siginfo' variable. */
9338 static const struct internalvar_funcs siginfo_funcs
=
9345 /* Callback for infrun's target events source. This is marked when a
9346 thread has a pending status to process. */
9349 infrun_async_inferior_event_handler (gdb_client_data data
)
9351 clear_async_event_handler (infrun_async_inferior_event_token
);
9352 inferior_event_handler (INF_REG_EVENT
);
9359 /* Verify that when two threads with the same ptid exist (from two different
9360 targets) and one of them changes ptid, we only update inferior_ptid if
9361 it is appropriate. */
9364 infrun_thread_ptid_changed ()
9366 gdbarch
*arch
= current_inferior ()->gdbarch
;
9368 /* The thread which inferior_ptid represents changes ptid. */
9370 scoped_restore_current_pspace_and_thread restore
;
9372 scoped_mock_context
<test_target_ops
> target1 (arch
);
9373 scoped_mock_context
<test_target_ops
> target2 (arch
);
9375 ptid_t
old_ptid (111, 222);
9376 ptid_t
new_ptid (111, 333);
9378 target1
.mock_inferior
.pid
= old_ptid
.pid ();
9379 target1
.mock_thread
.ptid
= old_ptid
;
9380 target1
.mock_inferior
.ptid_thread_map
.clear ();
9381 target1
.mock_inferior
.ptid_thread_map
[old_ptid
] = &target1
.mock_thread
;
9383 target2
.mock_inferior
.pid
= old_ptid
.pid ();
9384 target2
.mock_thread
.ptid
= old_ptid
;
9385 target2
.mock_inferior
.ptid_thread_map
.clear ();
9386 target2
.mock_inferior
.ptid_thread_map
[old_ptid
] = &target2
.mock_thread
;
9388 auto restore_inferior_ptid
= make_scoped_restore (&inferior_ptid
, old_ptid
);
9389 set_current_inferior (&target1
.mock_inferior
);
9391 thread_change_ptid (&target1
.mock_target
, old_ptid
, new_ptid
);
9393 gdb_assert (inferior_ptid
== new_ptid
);
9396 /* A thread with the same ptid as inferior_ptid, but from another target,
9399 scoped_restore_current_pspace_and_thread restore
;
9401 scoped_mock_context
<test_target_ops
> target1 (arch
);
9402 scoped_mock_context
<test_target_ops
> target2 (arch
);
9404 ptid_t
old_ptid (111, 222);
9405 ptid_t
new_ptid (111, 333);
9407 target1
.mock_inferior
.pid
= old_ptid
.pid ();
9408 target1
.mock_thread
.ptid
= old_ptid
;
9409 target1
.mock_inferior
.ptid_thread_map
.clear ();
9410 target1
.mock_inferior
.ptid_thread_map
[old_ptid
] = &target1
.mock_thread
;
9412 target2
.mock_inferior
.pid
= old_ptid
.pid ();
9413 target2
.mock_thread
.ptid
= old_ptid
;
9414 target2
.mock_inferior
.ptid_thread_map
.clear ();
9415 target2
.mock_inferior
.ptid_thread_map
[old_ptid
] = &target2
.mock_thread
;
9417 auto restore_inferior_ptid
= make_scoped_restore (&inferior_ptid
, old_ptid
);
9418 set_current_inferior (&target2
.mock_inferior
);
9420 thread_change_ptid (&target1
.mock_target
, old_ptid
, new_ptid
);
9422 gdb_assert (inferior_ptid
== old_ptid
);
9426 } /* namespace selftests */
9428 #endif /* GDB_SELF_TEST */
9430 void _initialize_infrun ();
9432 _initialize_infrun ()
9434 struct cmd_list_element
*c
;
9436 /* Register extra event sources in the event loop. */
9437 infrun_async_inferior_event_token
9438 = create_async_event_handler (infrun_async_inferior_event_handler
, NULL
,
9441 cmd_list_element
*info_signals_cmd
9442 = add_info ("signals", info_signals_command
, _("\
9443 What debugger does when program gets various signals.\n\
9444 Specify a signal as argument to print info on that signal only."));
9445 add_info_alias ("handle", info_signals_cmd
, 0);
9447 c
= add_com ("handle", class_run
, handle_command
, _("\
9448 Specify how to handle signals.\n\
9449 Usage: handle SIGNAL [ACTIONS]\n\
9450 Args are signals and actions to apply to those signals.\n\
9451 If no actions are specified, the current settings for the specified signals\n\
9452 will be displayed instead.\n\
9454 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
9455 from 1-15 are allowed for compatibility with old versions of GDB.\n\
9456 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
9457 The special arg \"all\" is recognized to mean all signals except those\n\
9458 used by the debugger, typically SIGTRAP and SIGINT.\n\
9460 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
9461 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
9462 Stop means reenter debugger if this signal happens (implies print).\n\
9463 Print means print a message if this signal happens.\n\
9464 Pass means let program see this signal; otherwise program doesn't know.\n\
9465 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
9466 Pass and Stop may be combined.\n\
9468 Multiple signals may be specified. Signal numbers and signal names\n\
9469 may be interspersed with actions, with the actions being performed for\n\
9470 all signals cumulatively specified."));
9471 set_cmd_completer (c
, handle_completer
);
9474 stop_command
= add_cmd ("stop", class_obscure
,
9475 not_just_help_class_command
, _("\
9476 There is no `stop' command, but you can set a hook on `stop'.\n\
9477 This allows you to set a list of commands to be run each time execution\n\
9478 of the program stops."), &cmdlist
);
9480 add_setshow_boolean_cmd
9481 ("infrun", class_maintenance
, &debug_infrun
,
9482 _("Set inferior debugging."),
9483 _("Show inferior debugging."),
9484 _("When non-zero, inferior specific debugging is enabled."),
9485 NULL
, show_debug_infrun
, &setdebuglist
, &showdebuglist
);
9487 add_setshow_boolean_cmd ("non-stop", no_class
,
9489 Set whether gdb controls the inferior in non-stop mode."), _("\
9490 Show whether gdb controls the inferior in non-stop mode."), _("\
9491 When debugging a multi-threaded program and this setting is\n\
9492 off (the default, also called all-stop mode), when one thread stops\n\
9493 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9494 all other threads in the program while you interact with the thread of\n\
9495 interest. When you continue or step a thread, you can allow the other\n\
9496 threads to run, or have them remain stopped, but while you inspect any\n\
9497 thread's state, all threads stop.\n\
9499 In non-stop mode, when one thread stops, other threads can continue\n\
9500 to run freely. You'll be able to step each thread independently,\n\
9501 leave it stopped or free to run as needed."),
9507 for (size_t i
= 0; i
< GDB_SIGNAL_LAST
; i
++)
9510 signal_print
[i
] = 1;
9511 signal_program
[i
] = 1;
9512 signal_catch
[i
] = 0;
9515 /* Signals caused by debugger's own actions should not be given to
9516 the program afterwards.
9518 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9519 explicitly specifies that it should be delivered to the target
9520 program. Typically, that would occur when a user is debugging a
9521 target monitor on a simulator: the target monitor sets a
9522 breakpoint; the simulator encounters this breakpoint and halts
9523 the simulation handing control to GDB; GDB, noting that the stop
9524 address doesn't map to any known breakpoint, returns control back
9525 to the simulator; the simulator then delivers the hardware
9526 equivalent of a GDB_SIGNAL_TRAP to the program being
9528 signal_program
[GDB_SIGNAL_TRAP
] = 0;
9529 signal_program
[GDB_SIGNAL_INT
] = 0;
9531 /* Signals that are not errors should not normally enter the debugger. */
9532 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
9533 signal_print
[GDB_SIGNAL_ALRM
] = 0;
9534 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
9535 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
9536 signal_stop
[GDB_SIGNAL_PROF
] = 0;
9537 signal_print
[GDB_SIGNAL_PROF
] = 0;
9538 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
9539 signal_print
[GDB_SIGNAL_CHLD
] = 0;
9540 signal_stop
[GDB_SIGNAL_IO
] = 0;
9541 signal_print
[GDB_SIGNAL_IO
] = 0;
9542 signal_stop
[GDB_SIGNAL_POLL
] = 0;
9543 signal_print
[GDB_SIGNAL_POLL
] = 0;
9544 signal_stop
[GDB_SIGNAL_URG
] = 0;
9545 signal_print
[GDB_SIGNAL_URG
] = 0;
9546 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
9547 signal_print
[GDB_SIGNAL_WINCH
] = 0;
9548 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
9549 signal_print
[GDB_SIGNAL_PRIO
] = 0;
9551 /* These signals are used internally by user-level thread
9552 implementations. (See signal(5) on Solaris.) Like the above
9553 signals, a healthy program receives and handles them as part of
9554 its normal operation. */
9555 signal_stop
[GDB_SIGNAL_LWP
] = 0;
9556 signal_print
[GDB_SIGNAL_LWP
] = 0;
9557 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
9558 signal_print
[GDB_SIGNAL_WAITING
] = 0;
9559 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
9560 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
9561 signal_stop
[GDB_SIGNAL_LIBRT
] = 0;
9562 signal_print
[GDB_SIGNAL_LIBRT
] = 0;
9564 /* Update cached state. */
9565 signal_cache_update (-1);
9567 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
9568 &stop_on_solib_events
, _("\
9569 Set stopping for shared library events."), _("\
9570 Show stopping for shared library events."), _("\
9571 If nonzero, gdb will give control to the user when the dynamic linker\n\
9572 notifies gdb of shared library events. The most common event of interest\n\
9573 to the user would be loading/unloading of a new library."),
9574 set_stop_on_solib_events
,
9575 show_stop_on_solib_events
,
9576 &setlist
, &showlist
);
9578 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
9579 follow_fork_mode_kind_names
,
9580 &follow_fork_mode_string
, _("\
9581 Set debugger response to a program call of fork or vfork."), _("\
9582 Show debugger response to a program call of fork or vfork."), _("\
9583 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9584 parent - the original process is debugged after a fork\n\
9585 child - the new process is debugged after a fork\n\
9586 The unfollowed process will continue to run.\n\
9587 By default, the debugger will follow the parent process."),
9589 show_follow_fork_mode_string
,
9590 &setlist
, &showlist
);
9592 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
9593 follow_exec_mode_names
,
9594 &follow_exec_mode_string
, _("\
9595 Set debugger response to a program call of exec."), _("\
9596 Show debugger response to a program call of exec."), _("\
9597 An exec call replaces the program image of a process.\n\
9599 follow-exec-mode can be:\n\
9601 new - the debugger creates a new inferior and rebinds the process\n\
9602 to this new inferior. The program the process was running before\n\
9603 the exec call can be restarted afterwards by restarting the original\n\
9606 same - the debugger keeps the process bound to the same inferior.\n\
9607 The new executable image replaces the previous executable loaded in\n\
9608 the inferior. Restarting the inferior after the exec call restarts\n\
9609 the executable the process was running after the exec call.\n\
9611 By default, the debugger will use the same inferior."),
9613 show_follow_exec_mode_string
,
9614 &setlist
, &showlist
);
9616 add_setshow_enum_cmd ("scheduler-locking", class_run
,
9617 scheduler_enums
, &scheduler_mode
, _("\
9618 Set mode for locking scheduler during execution."), _("\
9619 Show mode for locking scheduler during execution."), _("\
9620 off == no locking (threads may preempt at any time)\n\
9621 on == full locking (no thread except the current thread may run)\n\
9622 This applies to both normal execution and replay mode.\n\
9623 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9624 In this mode, other threads may run during other commands.\n\
9625 This applies to both normal execution and replay mode.\n\
9626 replay == scheduler locked in replay mode and unlocked during normal execution."),
9627 set_schedlock_func
, /* traps on target vector */
9628 show_scheduler_mode
,
9629 &setlist
, &showlist
);
9631 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
9632 Set mode for resuming threads of all processes."), _("\
9633 Show mode for resuming threads of all processes."), _("\
9634 When on, execution commands (such as 'continue' or 'next') resume all\n\
9635 threads of all processes. When off (which is the default), execution\n\
9636 commands only resume the threads of the current process. The set of\n\
9637 threads that are resumed is further refined by the scheduler-locking\n\
9638 mode (see help set scheduler-locking)."),
9640 show_schedule_multiple
,
9641 &setlist
, &showlist
);
9643 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
9644 Set mode of the step operation."), _("\
9645 Show mode of the step operation."), _("\
9646 When set, doing a step over a function without debug line information\n\
9647 will stop at the first instruction of that function. Otherwise, the\n\
9648 function is skipped and the step command stops at a different source line."),
9650 show_step_stop_if_no_debug
,
9651 &setlist
, &showlist
);
9653 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
9654 &can_use_displaced_stepping
, _("\
9655 Set debugger's willingness to use displaced stepping."), _("\
9656 Show debugger's willingness to use displaced stepping."), _("\
9657 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9658 supported by the target architecture. If off, gdb will not use displaced\n\
9659 stepping to step over breakpoints, even if such is supported by the target\n\
9660 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9661 if the target architecture supports it and non-stop mode is active, but will not\n\
9662 use it in all-stop mode (see help set non-stop)."),
9664 show_can_use_displaced_stepping
,
9665 &setlist
, &showlist
);
9667 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
9668 &exec_direction
, _("Set direction of execution.\n\
9669 Options are 'forward' or 'reverse'."),
9670 _("Show direction of execution (forward/reverse)."),
9671 _("Tells gdb whether to execute forward or backward."),
9672 set_exec_direction_func
, show_exec_direction_func
,
9673 &setlist
, &showlist
);
9675 /* Set/show detach-on-fork: user-settable mode. */
9677 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
9678 Set whether gdb will detach the child of a fork."), _("\
9679 Show whether gdb will detach the child of a fork."), _("\
9680 Tells gdb whether to detach the child of a fork."),
9681 NULL
, NULL
, &setlist
, &showlist
);
9683 /* Set/show disable address space randomization mode. */
9685 add_setshow_boolean_cmd ("disable-randomization", class_support
,
9686 &disable_randomization
, _("\
9687 Set disabling of debuggee's virtual address space randomization."), _("\
9688 Show disabling of debuggee's virtual address space randomization."), _("\
9689 When this mode is on (which is the default), randomization of the virtual\n\
9690 address space is disabled. Standalone programs run with the randomization\n\
9691 enabled by default on some platforms."),
9692 &set_disable_randomization
,
9693 &show_disable_randomization
,
9694 &setlist
, &showlist
);
9696 /* ptid initializations */
9697 inferior_ptid
= null_ptid
;
9698 target_last_wait_ptid
= minus_one_ptid
;
9700 gdb::observers::thread_ptid_changed
.attach (infrun_thread_ptid_changed
,
9702 gdb::observers::thread_stop_requested
.attach (infrun_thread_stop_requested
,
9704 gdb::observers::thread_exit
.attach (infrun_thread_thread_exit
, "infrun");
9705 gdb::observers::inferior_exit
.attach (infrun_inferior_exit
, "infrun");
9706 gdb::observers::inferior_execd
.attach (infrun_inferior_execd
, "infrun");
9708 /* Explicitly create without lookup, since that tries to create a
9709 value with a void typed value, and when we get here, gdbarch
9710 isn't initialized yet. At this point, we're quite sure there
9711 isn't another convenience variable of the same name. */
9712 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
9714 add_setshow_boolean_cmd ("observer", no_class
,
9715 &observer_mode_1
, _("\
9716 Set whether gdb controls the inferior in observer mode."), _("\
9717 Show whether gdb controls the inferior in observer mode."), _("\
9718 In observer mode, GDB can get data from the inferior, but not\n\
9719 affect its execution. Registers and memory may not be changed,\n\
9720 breakpoints may not be set, and the program cannot be interrupted\n\
9728 selftests::register_test ("infrun_thread_ptid_changed",
9729 selftests::infrun_thread_ptid_changed
);