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 threads of the parent the
859 user wanted to be executing. */
862 proceed_after_vfork_done (struct thread_info
*thread
,
865 int pid
= * (int *) arg
;
867 if (thread
->ptid
.pid () == pid
868 && thread
->state
== THREAD_RUNNING
869 && !thread
->executing
870 && !thread
->stop_requested
871 && thread
->stop_signal () == GDB_SIGNAL_0
)
873 infrun_debug_printf ("resuming vfork parent thread %s",
874 target_pid_to_str (thread
->ptid
).c_str ());
876 switch_to_thread (thread
);
877 clear_proceed_status (0);
878 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
);
884 /* Called whenever we notice an exec or exit event, to handle
885 detaching or resuming a vfork parent. */
888 handle_vfork_child_exec_or_exit (int exec
)
890 struct inferior
*inf
= current_inferior ();
892 if (inf
->vfork_parent
)
894 int resume_parent
= -1;
896 /* This exec or exit marks the end of the shared memory region
897 between the parent and the child. Break the bonds. */
898 inferior
*vfork_parent
= inf
->vfork_parent
;
899 inf
->vfork_parent
->vfork_child
= NULL
;
900 inf
->vfork_parent
= NULL
;
902 /* If the user wanted to detach from the parent, now is the
904 if (vfork_parent
->pending_detach
)
906 struct program_space
*pspace
;
907 struct address_space
*aspace
;
909 /* follow-fork child, detach-on-fork on. */
911 vfork_parent
->pending_detach
= 0;
913 scoped_restore_current_pspace_and_thread restore_thread
;
915 /* We're letting loose of the parent. */
916 thread_info
*tp
= any_live_thread_of_inferior (vfork_parent
);
917 switch_to_thread (tp
);
919 /* We're about to detach from the parent, which implicitly
920 removes breakpoints from its address space. There's a
921 catch here: we want to reuse the spaces for the child,
922 but, parent/child are still sharing the pspace at this
923 point, although the exec in reality makes the kernel give
924 the child a fresh set of new pages. The problem here is
925 that the breakpoints module being unaware of this, would
926 likely chose the child process to write to the parent
927 address space. Swapping the child temporarily away from
928 the spaces has the desired effect. Yes, this is "sort
931 pspace
= inf
->pspace
;
932 aspace
= inf
->aspace
;
936 if (print_inferior_events
)
939 = target_pid_to_str (ptid_t (vfork_parent
->pid
));
941 target_terminal::ours_for_output ();
945 fprintf_filtered (gdb_stdlog
,
946 _("[Detaching vfork parent %s "
947 "after child exec]\n"), pidstr
.c_str ());
951 fprintf_filtered (gdb_stdlog
,
952 _("[Detaching vfork parent %s "
953 "after child exit]\n"), pidstr
.c_str ());
957 target_detach (vfork_parent
, 0);
960 inf
->pspace
= pspace
;
961 inf
->aspace
= aspace
;
965 /* We're staying attached to the parent, so, really give the
966 child a new address space. */
967 inf
->pspace
= new program_space (maybe_new_address_space ());
968 inf
->aspace
= inf
->pspace
->aspace
;
970 set_current_program_space (inf
->pspace
);
972 resume_parent
= vfork_parent
->pid
;
976 /* If this is a vfork child exiting, then the pspace and
977 aspaces were shared with the parent. Since we're
978 reporting the process exit, we'll be mourning all that is
979 found in the address space, and switching to null_ptid,
980 preparing to start a new inferior. But, since we don't
981 want to clobber the parent's address/program spaces, we
982 go ahead and create a new one for this exiting
985 /* Switch to no-thread while running clone_program_space, so
986 that clone_program_space doesn't want to read the
987 selected frame of a dead process. */
988 scoped_restore_current_thread restore_thread
;
989 switch_to_no_thread ();
991 inf
->pspace
= new program_space (maybe_new_address_space ());
992 inf
->aspace
= inf
->pspace
->aspace
;
993 set_current_program_space (inf
->pspace
);
995 inf
->symfile_flags
= SYMFILE_NO_READ
;
996 clone_program_space (inf
->pspace
, vfork_parent
->pspace
);
998 resume_parent
= vfork_parent
->pid
;
1001 gdb_assert (current_program_space
== inf
->pspace
);
1003 if (non_stop
&& resume_parent
!= -1)
1005 /* If the user wanted the parent to be running, let it go
1007 scoped_restore_current_thread restore_thread
;
1009 infrun_debug_printf ("resuming vfork parent process %d",
1012 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
1017 /* Enum strings for "set|show follow-exec-mode". */
1019 static const char follow_exec_mode_new
[] = "new";
1020 static const char follow_exec_mode_same
[] = "same";
1021 static const char *const follow_exec_mode_names
[] =
1023 follow_exec_mode_new
,
1024 follow_exec_mode_same
,
1028 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1030 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1031 struct cmd_list_element
*c
, const char *value
)
1033 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1036 /* EXEC_FILE_TARGET is assumed to be non-NULL. */
1039 follow_exec (ptid_t ptid
, const char *exec_file_target
)
1041 int pid
= ptid
.pid ();
1042 ptid_t process_ptid
;
1044 /* Switch terminal for any messages produced e.g. by
1045 breakpoint_re_set. */
1046 target_terminal::ours_for_output ();
1048 /* This is an exec event that we actually wish to pay attention to.
1049 Refresh our symbol table to the newly exec'd program, remove any
1050 momentary bp's, etc.
1052 If there are breakpoints, they aren't really inserted now,
1053 since the exec() transformed our inferior into a fresh set
1056 We want to preserve symbolic breakpoints on the list, since
1057 we have hopes that they can be reset after the new a.out's
1058 symbol table is read.
1060 However, any "raw" breakpoints must be removed from the list
1061 (e.g., the solib bp's), since their address is probably invalid
1064 And, we DON'T want to call delete_breakpoints() here, since
1065 that may write the bp's "shadow contents" (the instruction
1066 value that was overwritten with a TRAP instruction). Since
1067 we now have a new a.out, those shadow contents aren't valid. */
1069 mark_breakpoints_out ();
1071 /* The target reports the exec event to the main thread, even if
1072 some other thread does the exec, and even if the main thread was
1073 stopped or already gone. We may still have non-leader threads of
1074 the process on our list. E.g., on targets that don't have thread
1075 exit events (like remote); or on native Linux in non-stop mode if
1076 there were only two threads in the inferior and the non-leader
1077 one is the one that execs (and nothing forces an update of the
1078 thread list up to here). When debugging remotely, it's best to
1079 avoid extra traffic, when possible, so avoid syncing the thread
1080 list with the target, and instead go ahead and delete all threads
1081 of the process but one that reported the event. Note this must
1082 be done before calling update_breakpoints_after_exec, as
1083 otherwise clearing the threads' resources would reference stale
1084 thread breakpoints -- it may have been one of these threads that
1085 stepped across the exec. We could just clear their stepping
1086 states, but as long as we're iterating, might as well delete
1087 them. Deleting them now rather than at the next user-visible
1088 stop provides a nicer sequence of events for user and MI
1090 for (thread_info
*th
: all_threads_safe ())
1091 if (th
->ptid
.pid () == pid
&& th
->ptid
!= ptid
)
1094 /* We also need to clear any left over stale state for the
1095 leader/event thread. E.g., if there was any step-resume
1096 breakpoint or similar, it's gone now. We cannot truly
1097 step-to-next statement through an exec(). */
1098 thread_info
*th
= inferior_thread ();
1099 th
->control
.step_resume_breakpoint
= NULL
;
1100 th
->control
.exception_resume_breakpoint
= NULL
;
1101 th
->control
.single_step_breakpoints
= NULL
;
1102 th
->control
.step_range_start
= 0;
1103 th
->control
.step_range_end
= 0;
1105 /* The user may have had the main thread held stopped in the
1106 previous image (e.g., schedlock on, or non-stop). Release
1108 th
->stop_requested
= 0;
1110 update_breakpoints_after_exec ();
1112 /* What is this a.out's name? */
1113 process_ptid
= ptid_t (pid
);
1114 printf_unfiltered (_("%s is executing new program: %s\n"),
1115 target_pid_to_str (process_ptid
).c_str (),
1118 /* We've followed the inferior through an exec. Therefore, the
1119 inferior has essentially been killed & reborn. */
1121 breakpoint_init_inferior (inf_execd
);
1123 gdb::unique_xmalloc_ptr
<char> exec_file_host
1124 = exec_file_find (exec_file_target
, NULL
);
1126 /* If we were unable to map the executable target pathname onto a host
1127 pathname, tell the user that. Otherwise GDB's subsequent behavior
1128 is confusing. Maybe it would even be better to stop at this point
1129 so that the user can specify a file manually before continuing. */
1130 if (exec_file_host
== NULL
)
1131 warning (_("Could not load symbols for executable %s.\n"
1132 "Do you need \"set sysroot\"?"),
1135 /* Reset the shared library package. This ensures that we get a
1136 shlib event when the child reaches "_start", at which point the
1137 dld will have had a chance to initialize the child. */
1138 /* Also, loading a symbol file below may trigger symbol lookups, and
1139 we don't want those to be satisfied by the libraries of the
1140 previous incarnation of this process. */
1141 no_shared_libraries (NULL
, 0);
1143 struct inferior
*inf
= current_inferior ();
1145 if (follow_exec_mode_string
== follow_exec_mode_new
)
1147 /* The user wants to keep the old inferior and program spaces
1148 around. Create a new fresh one, and switch to it. */
1150 /* Do exit processing for the original inferior before setting the new
1151 inferior's pid. Having two inferiors with the same pid would confuse
1152 find_inferior_p(t)id. Transfer the terminal state and info from the
1153 old to the new inferior. */
1154 inferior
*new_inferior
= add_inferior_with_spaces ();
1156 swap_terminal_info (new_inferior
, inf
);
1157 exit_inferior_silent (inf
);
1159 new_inferior
->pid
= pid
;
1160 target_follow_exec (new_inferior
, ptid
, exec_file_target
);
1162 /* We continue with the new inferior. */
1167 /* The old description may no longer be fit for the new image.
1168 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1169 old description; we'll read a new one below. No need to do
1170 this on "follow-exec-mode new", as the old inferior stays
1171 around (its description is later cleared/refetched on
1173 target_clear_description ();
1174 target_follow_exec (inf
, ptid
, exec_file_target
);
1177 gdb_assert (current_inferior () == inf
);
1178 gdb_assert (current_program_space
== inf
->pspace
);
1180 /* Attempt to open the exec file. SYMFILE_DEFER_BP_RESET is used
1181 because the proper displacement for a PIE (Position Independent
1182 Executable) main symbol file will only be computed by
1183 solib_create_inferior_hook below. breakpoint_re_set would fail
1184 to insert the breakpoints with the zero displacement. */
1185 try_open_exec_file (exec_file_host
.get (), inf
, SYMFILE_DEFER_BP_RESET
);
1187 /* If the target can specify a description, read it. Must do this
1188 after flipping to the new executable (because the target supplied
1189 description must be compatible with the executable's
1190 architecture, and the old executable may e.g., be 32-bit, while
1191 the new one 64-bit), and before anything involving memory or
1193 target_find_description ();
1195 gdb::observers::inferior_execd
.notify (inf
);
1197 breakpoint_re_set ();
1199 /* Reinsert all breakpoints. (Those which were symbolic have
1200 been reset to the proper address in the new a.out, thanks
1201 to symbol_file_command...). */
1202 insert_breakpoints ();
1204 /* The next resume of this inferior should bring it to the shlib
1205 startup breakpoints. (If the user had also set bp's on
1206 "main" from the old (parent) process, then they'll auto-
1207 matically get reset there in the new process.). */
1210 /* The chain of threads that need to do a step-over operation to get
1211 past e.g., a breakpoint. What technique is used to step over the
1212 breakpoint/watchpoint does not matter -- all threads end up in the
1213 same queue, to maintain rough temporal order of execution, in order
1214 to avoid starvation, otherwise, we could e.g., find ourselves
1215 constantly stepping the same couple threads past their breakpoints
1216 over and over, if the single-step finish fast enough. */
1217 thread_step_over_list global_thread_step_over_list
;
1219 /* Bit flags indicating what the thread needs to step over. */
1221 enum step_over_what_flag
1223 /* Step over a breakpoint. */
1224 STEP_OVER_BREAKPOINT
= 1,
1226 /* Step past a non-continuable watchpoint, in order to let the
1227 instruction execute so we can evaluate the watchpoint
1229 STEP_OVER_WATCHPOINT
= 2
1231 DEF_ENUM_FLAGS_TYPE (enum step_over_what_flag
, step_over_what
);
1233 /* Info about an instruction that is being stepped over. */
1235 struct step_over_info
1237 /* If we're stepping past a breakpoint, this is the address space
1238 and address of the instruction the breakpoint is set at. We'll
1239 skip inserting all breakpoints here. Valid iff ASPACE is
1241 const address_space
*aspace
= nullptr;
1242 CORE_ADDR address
= 0;
1244 /* The instruction being stepped over triggers a nonsteppable
1245 watchpoint. If true, we'll skip inserting watchpoints. */
1246 int nonsteppable_watchpoint_p
= 0;
1248 /* The thread's global number. */
1252 /* The step-over info of the location that is being stepped over.
1254 Note that with async/breakpoint always-inserted mode, a user might
1255 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1256 being stepped over. As setting a new breakpoint inserts all
1257 breakpoints, we need to make sure the breakpoint being stepped over
1258 isn't inserted then. We do that by only clearing the step-over
1259 info when the step-over is actually finished (or aborted).
1261 Presently GDB can only step over one breakpoint at any given time.
1262 Given threads that can't run code in the same address space as the
1263 breakpoint's can't really miss the breakpoint, GDB could be taught
1264 to step-over at most one breakpoint per address space (so this info
1265 could move to the address space object if/when GDB is extended).
1266 The set of breakpoints being stepped over will normally be much
1267 smaller than the set of all breakpoints, so a flag in the
1268 breakpoint location structure would be wasteful. A separate list
1269 also saves complexity and run-time, as otherwise we'd have to go
1270 through all breakpoint locations clearing their flag whenever we
1271 start a new sequence. Similar considerations weigh against storing
1272 this info in the thread object. Plus, not all step overs actually
1273 have breakpoint locations -- e.g., stepping past a single-step
1274 breakpoint, or stepping to complete a non-continuable
1276 static struct step_over_info step_over_info
;
1278 /* Record the address of the breakpoint/instruction we're currently
1280 N.B. We record the aspace and address now, instead of say just the thread,
1281 because when we need the info later the thread may be running. */
1284 set_step_over_info (const address_space
*aspace
, CORE_ADDR address
,
1285 int nonsteppable_watchpoint_p
,
1288 step_over_info
.aspace
= aspace
;
1289 step_over_info
.address
= address
;
1290 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1291 step_over_info
.thread
= thread
;
1294 /* Called when we're not longer stepping over a breakpoint / an
1295 instruction, so all breakpoints are free to be (re)inserted. */
1298 clear_step_over_info (void)
1300 infrun_debug_printf ("clearing step over info");
1301 step_over_info
.aspace
= NULL
;
1302 step_over_info
.address
= 0;
1303 step_over_info
.nonsteppable_watchpoint_p
= 0;
1304 step_over_info
.thread
= -1;
1310 stepping_past_instruction_at (struct address_space
*aspace
,
1313 return (step_over_info
.aspace
!= NULL
1314 && breakpoint_address_match (aspace
, address
,
1315 step_over_info
.aspace
,
1316 step_over_info
.address
));
1322 thread_is_stepping_over_breakpoint (int thread
)
1324 return (step_over_info
.thread
!= -1
1325 && thread
== step_over_info
.thread
);
1331 stepping_past_nonsteppable_watchpoint (void)
1333 return step_over_info
.nonsteppable_watchpoint_p
;
1336 /* Returns true if step-over info is valid. */
1339 step_over_info_valid_p (void)
1341 return (step_over_info
.aspace
!= NULL
1342 || stepping_past_nonsteppable_watchpoint ());
1346 /* Displaced stepping. */
1348 /* In non-stop debugging mode, we must take special care to manage
1349 breakpoints properly; in particular, the traditional strategy for
1350 stepping a thread past a breakpoint it has hit is unsuitable.
1351 'Displaced stepping' is a tactic for stepping one thread past a
1352 breakpoint it has hit while ensuring that other threads running
1353 concurrently will hit the breakpoint as they should.
1355 The traditional way to step a thread T off a breakpoint in a
1356 multi-threaded program in all-stop mode is as follows:
1358 a0) Initially, all threads are stopped, and breakpoints are not
1360 a1) We single-step T, leaving breakpoints uninserted.
1361 a2) We insert breakpoints, and resume all threads.
1363 In non-stop debugging, however, this strategy is unsuitable: we
1364 don't want to have to stop all threads in the system in order to
1365 continue or step T past a breakpoint. Instead, we use displaced
1368 n0) Initially, T is stopped, other threads are running, and
1369 breakpoints are inserted.
1370 n1) We copy the instruction "under" the breakpoint to a separate
1371 location, outside the main code stream, making any adjustments
1372 to the instruction, register, and memory state as directed by
1374 n2) We single-step T over the instruction at its new location.
1375 n3) We adjust the resulting register and memory state as directed
1376 by T's architecture. This includes resetting T's PC to point
1377 back into the main instruction stream.
1380 This approach depends on the following gdbarch methods:
1382 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1383 indicate where to copy the instruction, and how much space must
1384 be reserved there. We use these in step n1.
1386 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1387 address, and makes any necessary adjustments to the instruction,
1388 register contents, and memory. We use this in step n1.
1390 - gdbarch_displaced_step_fixup adjusts registers and memory after
1391 we have successfully single-stepped the instruction, to yield the
1392 same effect the instruction would have had if we had executed it
1393 at its original address. We use this in step n3.
1395 The gdbarch_displaced_step_copy_insn and
1396 gdbarch_displaced_step_fixup functions must be written so that
1397 copying an instruction with gdbarch_displaced_step_copy_insn,
1398 single-stepping across the copied instruction, and then applying
1399 gdbarch_displaced_insn_fixup should have the same effects on the
1400 thread's memory and registers as stepping the instruction in place
1401 would have. Exactly which responsibilities fall to the copy and
1402 which fall to the fixup is up to the author of those functions.
1404 See the comments in gdbarch.sh for details.
1406 Note that displaced stepping and software single-step cannot
1407 currently be used in combination, although with some care I think
1408 they could be made to. Software single-step works by placing
1409 breakpoints on all possible subsequent instructions; if the
1410 displaced instruction is a PC-relative jump, those breakpoints
1411 could fall in very strange places --- on pages that aren't
1412 executable, or at addresses that are not proper instruction
1413 boundaries. (We do generally let other threads run while we wait
1414 to hit the software single-step breakpoint, and they might
1415 encounter such a corrupted instruction.) One way to work around
1416 this would be to have gdbarch_displaced_step_copy_insn fully
1417 simulate the effect of PC-relative instructions (and return NULL)
1418 on architectures that use software single-stepping.
1420 In non-stop mode, we can have independent and simultaneous step
1421 requests, so more than one thread may need to simultaneously step
1422 over a breakpoint. The current implementation assumes there is
1423 only one scratch space per process. In this case, we have to
1424 serialize access to the scratch space. If thread A wants to step
1425 over a breakpoint, but we are currently waiting for some other
1426 thread to complete a displaced step, we leave thread A stopped and
1427 place it in the displaced_step_request_queue. Whenever a displaced
1428 step finishes, we pick the next thread in the queue and start a new
1429 displaced step operation on it. See displaced_step_prepare and
1430 displaced_step_finish for details. */
1432 /* Return true if THREAD is doing a displaced step. */
1435 displaced_step_in_progress_thread (thread_info
*thread
)
1437 gdb_assert (thread
!= NULL
);
1439 return thread
->displaced_step_state
.in_progress ();
1442 /* Return true if INF has a thread doing a displaced step. */
1445 displaced_step_in_progress (inferior
*inf
)
1447 return inf
->displaced_step_state
.in_progress_count
> 0;
1450 /* Return true if any thread is doing a displaced step. */
1453 displaced_step_in_progress_any_thread ()
1455 for (inferior
*inf
: all_non_exited_inferiors ())
1457 if (displaced_step_in_progress (inf
))
1465 infrun_inferior_exit (struct inferior
*inf
)
1467 inf
->displaced_step_state
.reset ();
1471 infrun_inferior_execd (inferior
*inf
)
1473 /* If some threads where was doing a displaced step in this inferior at the
1474 moment of the exec, they no longer exist. Even if the exec'ing thread
1475 doing a displaced step, we don't want to to any fixup nor restore displaced
1476 stepping buffer bytes. */
1477 inf
->displaced_step_state
.reset ();
1479 for (thread_info
*thread
: inf
->threads ())
1480 thread
->displaced_step_state
.reset ();
1482 /* Since an in-line step is done with everything else stopped, if there was
1483 one in progress at the time of the exec, it must have been the exec'ing
1485 clear_step_over_info ();
1488 /* If ON, and the architecture supports it, GDB will use displaced
1489 stepping to step over breakpoints. If OFF, or if the architecture
1490 doesn't support it, GDB will instead use the traditional
1491 hold-and-step approach. If AUTO (which is the default), GDB will
1492 decide which technique to use to step over breakpoints depending on
1493 whether the target works in a non-stop way (see use_displaced_stepping). */
1495 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1498 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1499 struct cmd_list_element
*c
,
1502 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1503 fprintf_filtered (file
,
1504 _("Debugger's willingness to use displaced stepping "
1505 "to step over breakpoints is %s (currently %s).\n"),
1506 value
, target_is_non_stop_p () ? "on" : "off");
1508 fprintf_filtered (file
,
1509 _("Debugger's willingness to use displaced stepping "
1510 "to step over breakpoints is %s.\n"), value
);
1513 /* Return true if the gdbarch implements the required methods to use
1514 displaced stepping. */
1517 gdbarch_supports_displaced_stepping (gdbarch
*arch
)
1519 /* Only check for the presence of `prepare`. The gdbarch verification ensures
1520 that if `prepare` is provided, so is `finish`. */
1521 return gdbarch_displaced_step_prepare_p (arch
);
1524 /* Return non-zero if displaced stepping can/should be used to step
1525 over breakpoints of thread TP. */
1528 use_displaced_stepping (thread_info
*tp
)
1530 /* If the user disabled it explicitly, don't use displaced stepping. */
1531 if (can_use_displaced_stepping
== AUTO_BOOLEAN_FALSE
)
1534 /* If "auto", only use displaced stepping if the target operates in a non-stop
1536 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
1537 && !target_is_non_stop_p ())
1540 gdbarch
*gdbarch
= get_thread_regcache (tp
)->arch ();
1542 /* If the architecture doesn't implement displaced stepping, don't use
1544 if (!gdbarch_supports_displaced_stepping (gdbarch
))
1547 /* If recording, don't use displaced stepping. */
1548 if (find_record_target () != nullptr)
1551 /* If displaced stepping failed before for this inferior, don't bother trying
1553 if (tp
->inf
->displaced_step_state
.failed_before
)
1559 /* Simple function wrapper around displaced_step_thread_state::reset. */
1562 displaced_step_reset (displaced_step_thread_state
*displaced
)
1564 displaced
->reset ();
1567 /* A cleanup that wraps displaced_step_reset. We use this instead of, say,
1568 SCOPE_EXIT, because it needs to be discardable with "cleanup.release ()". */
1570 using displaced_step_reset_cleanup
= FORWARD_SCOPE_EXIT (displaced_step_reset
);
1575 displaced_step_dump_bytes (const gdb_byte
*buf
, size_t len
)
1579 for (size_t i
= 0; i
< len
; i
++)
1582 ret
+= string_printf ("%02x", buf
[i
]);
1584 ret
+= string_printf (" %02x", buf
[i
]);
1590 /* Prepare to single-step, using displaced stepping.
1592 Note that we cannot use displaced stepping when we have a signal to
1593 deliver. If we have a signal to deliver and an instruction to step
1594 over, then after the step, there will be no indication from the
1595 target whether the thread entered a signal handler or ignored the
1596 signal and stepped over the instruction successfully --- both cases
1597 result in a simple SIGTRAP. In the first case we mustn't do a
1598 fixup, and in the second case we must --- but we can't tell which.
1599 Comments in the code for 'random signals' in handle_inferior_event
1600 explain how we handle this case instead.
1602 Returns DISPLACED_STEP_PREPARE_STATUS_OK if preparing was successful -- this
1603 thread is going to be stepped now; DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE
1604 if displaced stepping this thread got queued; or
1605 DISPLACED_STEP_PREPARE_STATUS_CANT if this instruction can't be displaced
1608 static displaced_step_prepare_status
1609 displaced_step_prepare_throw (thread_info
*tp
)
1611 regcache
*regcache
= get_thread_regcache (tp
);
1612 struct gdbarch
*gdbarch
= regcache
->arch ();
1613 displaced_step_thread_state
&disp_step_thread_state
1614 = tp
->displaced_step_state
;
1616 /* We should never reach this function if the architecture does not
1617 support displaced stepping. */
1618 gdb_assert (gdbarch_supports_displaced_stepping (gdbarch
));
1620 /* Nor if the thread isn't meant to step over a breakpoint. */
1621 gdb_assert (tp
->control
.trap_expected
);
1623 /* Disable range stepping while executing in the scratch pad. We
1624 want a single-step even if executing the displaced instruction in
1625 the scratch buffer lands within the stepping range (e.g., a
1627 tp
->control
.may_range_step
= 0;
1629 /* We are about to start a displaced step for this thread. If one is already
1630 in progress, something's wrong. */
1631 gdb_assert (!disp_step_thread_state
.in_progress ());
1633 if (tp
->inf
->displaced_step_state
.unavailable
)
1635 /* The gdbarch tells us it's not worth asking to try a prepare because
1636 it is likely that it will return unavailable, so don't bother asking. */
1638 displaced_debug_printf ("deferring step of %s",
1639 target_pid_to_str (tp
->ptid
).c_str ());
1641 global_thread_step_over_chain_enqueue (tp
);
1642 return DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE
;
1645 displaced_debug_printf ("displaced-stepping %s now",
1646 target_pid_to_str (tp
->ptid
).c_str ());
1648 scoped_restore_current_thread restore_thread
;
1650 switch_to_thread (tp
);
1652 CORE_ADDR original_pc
= regcache_read_pc (regcache
);
1653 CORE_ADDR displaced_pc
;
1655 displaced_step_prepare_status status
1656 = gdbarch_displaced_step_prepare (gdbarch
, tp
, displaced_pc
);
1658 if (status
== DISPLACED_STEP_PREPARE_STATUS_CANT
)
1660 displaced_debug_printf ("failed to prepare (%s)",
1661 target_pid_to_str (tp
->ptid
).c_str ());
1663 return DISPLACED_STEP_PREPARE_STATUS_CANT
;
1665 else if (status
== DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE
)
1667 /* Not enough displaced stepping resources available, defer this
1668 request by placing it the queue. */
1670 displaced_debug_printf ("not enough resources available, "
1671 "deferring step of %s",
1672 target_pid_to_str (tp
->ptid
).c_str ());
1674 global_thread_step_over_chain_enqueue (tp
);
1676 return DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE
;
1679 gdb_assert (status
== DISPLACED_STEP_PREPARE_STATUS_OK
);
1681 /* Save the information we need to fix things up if the step
1683 disp_step_thread_state
.set (gdbarch
);
1685 tp
->inf
->displaced_step_state
.in_progress_count
++;
1687 displaced_debug_printf ("prepared successfully thread=%s, "
1688 "original_pc=%s, displaced_pc=%s",
1689 target_pid_to_str (tp
->ptid
).c_str (),
1690 paddress (gdbarch
, original_pc
),
1691 paddress (gdbarch
, displaced_pc
));
1693 return DISPLACED_STEP_PREPARE_STATUS_OK
;
1696 /* Wrapper for displaced_step_prepare_throw that disabled further
1697 attempts at displaced stepping if we get a memory error. */
1699 static displaced_step_prepare_status
1700 displaced_step_prepare (thread_info
*thread
)
1702 displaced_step_prepare_status status
1703 = DISPLACED_STEP_PREPARE_STATUS_CANT
;
1707 status
= displaced_step_prepare_throw (thread
);
1709 catch (const gdb_exception_error
&ex
)
1711 if (ex
.error
!= MEMORY_ERROR
1712 && ex
.error
!= NOT_SUPPORTED_ERROR
)
1715 infrun_debug_printf ("caught exception, disabling displaced stepping: %s",
1718 /* Be verbose if "set displaced-stepping" is "on", silent if
1720 if (can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1722 warning (_("disabling displaced stepping: %s"),
1726 /* Disable further displaced stepping attempts. */
1727 thread
->inf
->displaced_step_state
.failed_before
= 1;
1733 /* If we displaced stepped an instruction successfully, adjust registers and
1734 memory to yield the same effect the instruction would have had if we had
1735 executed it at its original address, and return
1736 DISPLACED_STEP_FINISH_STATUS_OK. If the instruction didn't complete,
1737 relocate the PC and return DISPLACED_STEP_FINISH_STATUS_NOT_EXECUTED.
1739 If the thread wasn't displaced stepping, return
1740 DISPLACED_STEP_FINISH_STATUS_OK as well. */
1742 static displaced_step_finish_status
1743 displaced_step_finish (thread_info
*event_thread
, enum gdb_signal signal
)
1745 displaced_step_thread_state
*displaced
= &event_thread
->displaced_step_state
;
1747 /* Was this thread performing a displaced step? */
1748 if (!displaced
->in_progress ())
1749 return DISPLACED_STEP_FINISH_STATUS_OK
;
1751 gdb_assert (event_thread
->inf
->displaced_step_state
.in_progress_count
> 0);
1752 event_thread
->inf
->displaced_step_state
.in_progress_count
--;
1754 /* Fixup may need to read memory/registers. Switch to the thread
1755 that we're fixing up. Also, target_stopped_by_watchpoint checks
1756 the current thread, and displaced_step_restore performs ptid-dependent
1757 memory accesses using current_inferior(). */
1758 switch_to_thread (event_thread
);
1760 displaced_step_reset_cleanup
cleanup (displaced
);
1762 /* Do the fixup, and release the resources acquired to do the displaced
1764 return gdbarch_displaced_step_finish (displaced
->get_original_gdbarch (),
1765 event_thread
, signal
);
1768 /* Data to be passed around while handling an event. This data is
1769 discarded between events. */
1770 struct execution_control_state
1772 process_stratum_target
*target
;
1774 /* The thread that got the event, if this was a thread event; NULL
1776 struct thread_info
*event_thread
;
1778 struct target_waitstatus ws
;
1779 int stop_func_filled_in
;
1780 CORE_ADDR stop_func_start
;
1781 CORE_ADDR stop_func_end
;
1782 const char *stop_func_name
;
1785 /* True if the event thread hit the single-step breakpoint of
1786 another thread. Thus the event doesn't cause a stop, the thread
1787 needs to be single-stepped past the single-step breakpoint before
1788 we can switch back to the original stepping thread. */
1789 int hit_singlestep_breakpoint
;
1792 /* Clear ECS and set it to point at TP. */
1795 reset_ecs (struct execution_control_state
*ecs
, struct thread_info
*tp
)
1797 memset (ecs
, 0, sizeof (*ecs
));
1798 ecs
->event_thread
= tp
;
1799 ecs
->ptid
= tp
->ptid
;
1802 static void keep_going_pass_signal (struct execution_control_state
*ecs
);
1803 static void prepare_to_wait (struct execution_control_state
*ecs
);
1804 static bool keep_going_stepped_thread (struct thread_info
*tp
);
1805 static step_over_what
thread_still_needs_step_over (struct thread_info
*tp
);
1807 /* Are there any pending step-over requests? If so, run all we can
1808 now and return true. Otherwise, return false. */
1811 start_step_over (void)
1813 INFRUN_SCOPED_DEBUG_ENTER_EXIT
;
1815 /* Don't start a new step-over if we already have an in-line
1816 step-over operation ongoing. */
1817 if (step_over_info_valid_p ())
1820 /* Steal the global thread step over chain. As we try to initiate displaced
1821 steps, threads will be enqueued in the global chain if no buffers are
1822 available. If we iterated on the global chain directly, we might iterate
1824 thread_step_over_list threads_to_step
1825 = std::move (global_thread_step_over_list
);
1827 infrun_debug_printf ("stealing global queue of threads to step, length = %d",
1828 thread_step_over_chain_length (threads_to_step
));
1830 bool started
= false;
1832 /* On scope exit (whatever the reason, return or exception), if there are
1833 threads left in the THREADS_TO_STEP chain, put back these threads in the
1837 if (threads_to_step
.empty ())
1838 infrun_debug_printf ("step-over queue now empty");
1841 infrun_debug_printf ("putting back %d threads to step in global queue",
1842 thread_step_over_chain_length (threads_to_step
));
1844 global_thread_step_over_chain_enqueue_chain
1845 (std::move (threads_to_step
));
1849 thread_step_over_list_safe_range range
1850 = make_thread_step_over_list_safe_range (threads_to_step
);
1852 for (thread_info
*tp
: range
)
1854 struct execution_control_state ecss
;
1855 struct execution_control_state
*ecs
= &ecss
;
1856 step_over_what step_what
;
1857 int must_be_in_line
;
1859 gdb_assert (!tp
->stop_requested
);
1861 if (tp
->inf
->displaced_step_state
.unavailable
)
1863 /* The arch told us to not even try preparing another displaced step
1864 for this inferior. Just leave the thread in THREADS_TO_STEP, it
1865 will get moved to the global chain on scope exit. */
1869 /* Remove thread from the THREADS_TO_STEP chain. If anything goes wrong
1870 while we try to prepare the displaced step, we don't add it back to
1871 the global step over chain. This is to avoid a thread staying in the
1872 step over chain indefinitely if something goes wrong when resuming it
1873 If the error is intermittent and it still needs a step over, it will
1874 get enqueued again when we try to resume it normally. */
1875 threads_to_step
.erase (threads_to_step
.iterator_to (*tp
));
1877 step_what
= thread_still_needs_step_over (tp
);
1878 must_be_in_line
= ((step_what
& STEP_OVER_WATCHPOINT
)
1879 || ((step_what
& STEP_OVER_BREAKPOINT
)
1880 && !use_displaced_stepping (tp
)));
1882 /* We currently stop all threads of all processes to step-over
1883 in-line. If we need to start a new in-line step-over, let
1884 any pending displaced steps finish first. */
1885 if (must_be_in_line
&& displaced_step_in_progress_any_thread ())
1887 global_thread_step_over_chain_enqueue (tp
);
1891 if (tp
->control
.trap_expected
1895 internal_error (__FILE__
, __LINE__
,
1896 "[%s] has inconsistent state: "
1897 "trap_expected=%d, resumed=%d, executing=%d\n",
1898 target_pid_to_str (tp
->ptid
).c_str (),
1899 tp
->control
.trap_expected
,
1904 infrun_debug_printf ("resuming [%s] for step-over",
1905 target_pid_to_str (tp
->ptid
).c_str ());
1907 /* keep_going_pass_signal skips the step-over if the breakpoint
1908 is no longer inserted. In all-stop, we want to keep looking
1909 for a thread that needs a step-over instead of resuming TP,
1910 because we wouldn't be able to resume anything else until the
1911 target stops again. In non-stop, the resume always resumes
1912 only TP, so it's OK to let the thread resume freely. */
1913 if (!target_is_non_stop_p () && !step_what
)
1916 switch_to_thread (tp
);
1917 reset_ecs (ecs
, tp
);
1918 keep_going_pass_signal (ecs
);
1920 if (!ecs
->wait_some_more
)
1921 error (_("Command aborted."));
1923 /* If the thread's step over could not be initiated because no buffers
1924 were available, it was re-added to the global step over chain. */
1927 infrun_debug_printf ("[%s] was resumed.",
1928 target_pid_to_str (tp
->ptid
).c_str ());
1929 gdb_assert (!thread_is_in_step_over_chain (tp
));
1933 infrun_debug_printf ("[%s] was NOT resumed.",
1934 target_pid_to_str (tp
->ptid
).c_str ());
1935 gdb_assert (thread_is_in_step_over_chain (tp
));
1938 /* If we started a new in-line step-over, we're done. */
1939 if (step_over_info_valid_p ())
1941 gdb_assert (tp
->control
.trap_expected
);
1946 if (!target_is_non_stop_p ())
1948 /* On all-stop, shouldn't have resumed unless we needed a
1950 gdb_assert (tp
->control
.trap_expected
1951 || tp
->step_after_step_resume_breakpoint
);
1953 /* With remote targets (at least), in all-stop, we can't
1954 issue any further remote commands until the program stops
1960 /* Either the thread no longer needed a step-over, or a new
1961 displaced stepping sequence started. Even in the latter
1962 case, continue looking. Maybe we can also start another
1963 displaced step on a thread of other process. */
1969 /* Update global variables holding ptids to hold NEW_PTID if they were
1970 holding OLD_PTID. */
1972 infrun_thread_ptid_changed (process_stratum_target
*target
,
1973 ptid_t old_ptid
, ptid_t new_ptid
)
1975 if (inferior_ptid
== old_ptid
1976 && current_inferior ()->process_target () == target
)
1977 inferior_ptid
= new_ptid
;
1982 static const char schedlock_off
[] = "off";
1983 static const char schedlock_on
[] = "on";
1984 static const char schedlock_step
[] = "step";
1985 static const char schedlock_replay
[] = "replay";
1986 static const char *const scheduler_enums
[] = {
1993 static const char *scheduler_mode
= schedlock_replay
;
1995 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
1996 struct cmd_list_element
*c
, const char *value
)
1998 fprintf_filtered (file
,
1999 _("Mode for locking scheduler "
2000 "during execution is \"%s\".\n"),
2005 set_schedlock_func (const char *args
, int from_tty
, struct cmd_list_element
*c
)
2007 if (!target_can_lock_scheduler ())
2009 scheduler_mode
= schedlock_off
;
2010 error (_("Target '%s' cannot support this command."),
2011 target_shortname ());
2015 /* True if execution commands resume all threads of all processes by
2016 default; otherwise, resume only threads of the current inferior
2018 bool sched_multi
= false;
2020 /* Try to setup for software single stepping. Return true if target_resume()
2021 should use hardware single step.
2023 GDBARCH the current gdbarch. */
2026 maybe_software_singlestep (struct gdbarch
*gdbarch
)
2028 bool hw_step
= true;
2030 if (execution_direction
== EXEC_FORWARD
2031 && gdbarch_software_single_step_p (gdbarch
))
2032 hw_step
= !insert_single_step_breakpoints (gdbarch
);
2040 user_visible_resume_ptid (int step
)
2046 /* With non-stop mode on, threads are always handled
2048 resume_ptid
= inferior_ptid
;
2050 else if ((scheduler_mode
== schedlock_on
)
2051 || (scheduler_mode
== schedlock_step
&& step
))
2053 /* User-settable 'scheduler' mode requires solo thread
2055 resume_ptid
= inferior_ptid
;
2057 else if ((scheduler_mode
== schedlock_replay
)
2058 && target_record_will_replay (minus_one_ptid
, execution_direction
))
2060 /* User-settable 'scheduler' mode requires solo thread resume in replay
2062 resume_ptid
= inferior_ptid
;
2064 else if (!sched_multi
&& target_supports_multi_process ())
2066 /* Resume all threads of the current process (and none of other
2068 resume_ptid
= ptid_t (inferior_ptid
.pid ());
2072 /* Resume all threads of all processes. */
2073 resume_ptid
= RESUME_ALL
;
2081 process_stratum_target
*
2082 user_visible_resume_target (ptid_t resume_ptid
)
2084 return (resume_ptid
== minus_one_ptid
&& sched_multi
2086 : current_inferior ()->process_target ());
2089 /* Return a ptid representing the set of threads that we will resume,
2090 in the perspective of the target, assuming run control handling
2091 does not require leaving some threads stopped (e.g., stepping past
2092 breakpoint). USER_STEP indicates whether we're about to start the
2093 target for a stepping command. */
2096 internal_resume_ptid (int user_step
)
2098 /* In non-stop, we always control threads individually. Note that
2099 the target may always work in non-stop mode even with "set
2100 non-stop off", in which case user_visible_resume_ptid could
2101 return a wildcard ptid. */
2102 if (target_is_non_stop_p ())
2103 return inferior_ptid
;
2105 return user_visible_resume_ptid (user_step
);
2108 /* Wrapper for target_resume, that handles infrun-specific
2112 do_target_resume (ptid_t resume_ptid
, bool step
, enum gdb_signal sig
)
2114 struct thread_info
*tp
= inferior_thread ();
2116 gdb_assert (!tp
->stop_requested
);
2118 /* Install inferior's terminal modes. */
2119 target_terminal::inferior ();
2121 /* Avoid confusing the next resume, if the next stop/resume
2122 happens to apply to another thread. */
2123 tp
->set_stop_signal (GDB_SIGNAL_0
);
2125 /* Advise target which signals may be handled silently.
2127 If we have removed breakpoints because we are stepping over one
2128 in-line (in any thread), we need to receive all signals to avoid
2129 accidentally skipping a breakpoint during execution of a signal
2132 Likewise if we're displaced stepping, otherwise a trap for a
2133 breakpoint in a signal handler might be confused with the
2134 displaced step finishing. We don't make the displaced_step_finish
2135 step distinguish the cases instead, because:
2137 - a backtrace while stopped in the signal handler would show the
2138 scratch pad as frame older than the signal handler, instead of
2139 the real mainline code.
2141 - when the thread is later resumed, the signal handler would
2142 return to the scratch pad area, which would no longer be
2144 if (step_over_info_valid_p ()
2145 || displaced_step_in_progress (tp
->inf
))
2146 target_pass_signals ({});
2148 target_pass_signals (signal_pass
);
2150 target_resume (resume_ptid
, step
, sig
);
2152 if (target_can_async_p ())
2156 /* Resume the inferior. SIG is the signal to give the inferior
2157 (GDB_SIGNAL_0 for none). Note: don't call this directly; instead
2158 call 'resume', which handles exceptions. */
2161 resume_1 (enum gdb_signal sig
)
2163 struct regcache
*regcache
= get_current_regcache ();
2164 struct gdbarch
*gdbarch
= regcache
->arch ();
2165 struct thread_info
*tp
= inferior_thread ();
2166 const address_space
*aspace
= regcache
->aspace ();
2168 /* This represents the user's step vs continue request. When
2169 deciding whether "set scheduler-locking step" applies, it's the
2170 user's intention that counts. */
2171 const int user_step
= tp
->control
.stepping_command
;
2172 /* This represents what we'll actually request the target to do.
2173 This can decay from a step to a continue, if e.g., we need to
2174 implement single-stepping with breakpoints (software
2178 gdb_assert (!tp
->stop_requested
);
2179 gdb_assert (!thread_is_in_step_over_chain (tp
));
2181 if (tp
->has_pending_waitstatus ())
2184 ("thread %s has pending wait "
2185 "status %s (currently_stepping=%d).",
2186 target_pid_to_str (tp
->ptid
).c_str (),
2187 target_waitstatus_to_string (&tp
->pending_waitstatus ()).c_str (),
2188 currently_stepping (tp
));
2190 tp
->inf
->process_target ()->threads_executing
= true;
2191 tp
->set_resumed (true);
2193 /* FIXME: What should we do if we are supposed to resume this
2194 thread with a signal? Maybe we should maintain a queue of
2195 pending signals to deliver. */
2196 if (sig
!= GDB_SIGNAL_0
)
2198 warning (_("Couldn't deliver signal %s to %s."),
2199 gdb_signal_to_name (sig
),
2200 target_pid_to_str (tp
->ptid
).c_str ());
2203 tp
->set_stop_signal (GDB_SIGNAL_0
);
2205 if (target_can_async_p ())
2208 /* Tell the event loop we have an event to process. */
2209 mark_async_event_handler (infrun_async_inferior_event_token
);
2214 tp
->stepped_breakpoint
= 0;
2216 /* Depends on stepped_breakpoint. */
2217 step
= currently_stepping (tp
);
2219 if (current_inferior ()->waiting_for_vfork_done
)
2221 /* Don't try to single-step a vfork parent that is waiting for
2222 the child to get out of the shared memory region (by exec'ing
2223 or exiting). This is particularly important on software
2224 single-step archs, as the child process would trip on the
2225 software single step breakpoint inserted for the parent
2226 process. Since the parent will not actually execute any
2227 instruction until the child is out of the shared region (such
2228 are vfork's semantics), it is safe to simply continue it.
2229 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2230 the parent, and tell it to `keep_going', which automatically
2231 re-sets it stepping. */
2232 infrun_debug_printf ("resume : clear step");
2236 CORE_ADDR pc
= regcache_read_pc (regcache
);
2238 infrun_debug_printf ("step=%d, signal=%s, trap_expected=%d, "
2239 "current thread [%s] at %s",
2240 step
, gdb_signal_to_symbol_string (sig
),
2241 tp
->control
.trap_expected
,
2242 target_pid_to_str (inferior_ptid
).c_str (),
2243 paddress (gdbarch
, pc
));
2245 /* Normally, by the time we reach `resume', the breakpoints are either
2246 removed or inserted, as appropriate. The exception is if we're sitting
2247 at a permanent breakpoint; we need to step over it, but permanent
2248 breakpoints can't be removed. So we have to test for it here. */
2249 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2251 if (sig
!= GDB_SIGNAL_0
)
2253 /* We have a signal to pass to the inferior. The resume
2254 may, or may not take us to the signal handler. If this
2255 is a step, we'll need to stop in the signal handler, if
2256 there's one, (if the target supports stepping into
2257 handlers), or in the next mainline instruction, if
2258 there's no handler. If this is a continue, we need to be
2259 sure to run the handler with all breakpoints inserted.
2260 In all cases, set a breakpoint at the current address
2261 (where the handler returns to), and once that breakpoint
2262 is hit, resume skipping the permanent breakpoint. If
2263 that breakpoint isn't hit, then we've stepped into the
2264 signal handler (or hit some other event). We'll delete
2265 the step-resume breakpoint then. */
2267 infrun_debug_printf ("resume: skipping permanent breakpoint, "
2268 "deliver signal first");
2270 clear_step_over_info ();
2271 tp
->control
.trap_expected
= 0;
2273 if (tp
->control
.step_resume_breakpoint
== NULL
)
2275 /* Set a "high-priority" step-resume, as we don't want
2276 user breakpoints at PC to trigger (again) when this
2278 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2279 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2281 tp
->step_after_step_resume_breakpoint
= step
;
2284 insert_breakpoints ();
2288 /* There's no signal to pass, we can go ahead and skip the
2289 permanent breakpoint manually. */
2290 infrun_debug_printf ("skipping permanent breakpoint");
2291 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2292 /* Update pc to reflect the new address from which we will
2293 execute instructions. */
2294 pc
= regcache_read_pc (regcache
);
2298 /* We've already advanced the PC, so the stepping part
2299 is done. Now we need to arrange for a trap to be
2300 reported to handle_inferior_event. Set a breakpoint
2301 at the current PC, and run to it. Don't update
2302 prev_pc, because if we end in
2303 switch_back_to_stepped_thread, we want the "expected
2304 thread advanced also" branch to be taken. IOW, we
2305 don't want this thread to step further from PC
2307 gdb_assert (!step_over_info_valid_p ());
2308 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2309 insert_breakpoints ();
2311 resume_ptid
= internal_resume_ptid (user_step
);
2312 do_target_resume (resume_ptid
, false, GDB_SIGNAL_0
);
2313 tp
->set_resumed (true);
2319 /* If we have a breakpoint to step over, make sure to do a single
2320 step only. Same if we have software watchpoints. */
2321 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2322 tp
->control
.may_range_step
= 0;
2324 /* If displaced stepping is enabled, step over breakpoints by executing a
2325 copy of the instruction at a different address.
2327 We can't use displaced stepping when we have a signal to deliver;
2328 the comments for displaced_step_prepare explain why. The
2329 comments in the handle_inferior event for dealing with 'random
2330 signals' explain what we do instead.
2332 We can't use displaced stepping when we are waiting for vfork_done
2333 event, displaced stepping breaks the vfork child similarly as single
2334 step software breakpoint. */
2335 if (tp
->control
.trap_expected
2336 && use_displaced_stepping (tp
)
2337 && !step_over_info_valid_p ()
2338 && sig
== GDB_SIGNAL_0
2339 && !current_inferior ()->waiting_for_vfork_done
)
2341 displaced_step_prepare_status prepare_status
2342 = displaced_step_prepare (tp
);
2344 if (prepare_status
== DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE
)
2346 infrun_debug_printf ("Got placed in step-over queue");
2348 tp
->control
.trap_expected
= 0;
2351 else if (prepare_status
== DISPLACED_STEP_PREPARE_STATUS_CANT
)
2353 /* Fallback to stepping over the breakpoint in-line. */
2355 if (target_is_non_stop_p ())
2356 stop_all_threads ();
2358 set_step_over_info (regcache
->aspace (),
2359 regcache_read_pc (regcache
), 0, tp
->global_num
);
2361 step
= maybe_software_singlestep (gdbarch
);
2363 insert_breakpoints ();
2365 else if (prepare_status
== DISPLACED_STEP_PREPARE_STATUS_OK
)
2367 /* Update pc to reflect the new address from which we will
2368 execute instructions due to displaced stepping. */
2369 pc
= regcache_read_pc (get_thread_regcache (tp
));
2371 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
);
2374 gdb_assert_not_reached (_("Invalid displaced_step_prepare_status "
2378 /* Do we need to do it the hard way, w/temp breakpoints? */
2380 step
= maybe_software_singlestep (gdbarch
);
2382 /* Currently, our software single-step implementation leads to different
2383 results than hardware single-stepping in one situation: when stepping
2384 into delivering a signal which has an associated signal handler,
2385 hardware single-step will stop at the first instruction of the handler,
2386 while software single-step will simply skip execution of the handler.
2388 For now, this difference in behavior is accepted since there is no
2389 easy way to actually implement single-stepping into a signal handler
2390 without kernel support.
2392 However, there is one scenario where this difference leads to follow-on
2393 problems: if we're stepping off a breakpoint by removing all breakpoints
2394 and then single-stepping. In this case, the software single-step
2395 behavior means that even if there is a *breakpoint* in the signal
2396 handler, GDB still would not stop.
2398 Fortunately, we can at least fix this particular issue. We detect
2399 here the case where we are about to deliver a signal while software
2400 single-stepping with breakpoints removed. In this situation, we
2401 revert the decisions to remove all breakpoints and insert single-
2402 step breakpoints, and instead we install a step-resume breakpoint
2403 at the current address, deliver the signal without stepping, and
2404 once we arrive back at the step-resume breakpoint, actually step
2405 over the breakpoint we originally wanted to step over. */
2406 if (thread_has_single_step_breakpoints_set (tp
)
2407 && sig
!= GDB_SIGNAL_0
2408 && step_over_info_valid_p ())
2410 /* If we have nested signals or a pending signal is delivered
2411 immediately after a handler returns, might already have
2412 a step-resume breakpoint set on the earlier handler. We cannot
2413 set another step-resume breakpoint; just continue on until the
2414 original breakpoint is hit. */
2415 if (tp
->control
.step_resume_breakpoint
== NULL
)
2417 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2418 tp
->step_after_step_resume_breakpoint
= 1;
2421 delete_single_step_breakpoints (tp
);
2423 clear_step_over_info ();
2424 tp
->control
.trap_expected
= 0;
2426 insert_breakpoints ();
2429 /* If STEP is set, it's a request to use hardware stepping
2430 facilities. But in that case, we should never
2431 use singlestep breakpoint. */
2432 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2434 /* Decide the set of threads to ask the target to resume. */
2435 if (tp
->control
.trap_expected
)
2437 /* We're allowing a thread to run past a breakpoint it has
2438 hit, either by single-stepping the thread with the breakpoint
2439 removed, or by displaced stepping, with the breakpoint inserted.
2440 In the former case, we need to single-step only this thread,
2441 and keep others stopped, as they can miss this breakpoint if
2442 allowed to run. That's not really a problem for displaced
2443 stepping, but, we still keep other threads stopped, in case
2444 another thread is also stopped for a breakpoint waiting for
2445 its turn in the displaced stepping queue. */
2446 resume_ptid
= inferior_ptid
;
2449 resume_ptid
= internal_resume_ptid (user_step
);
2451 if (execution_direction
!= EXEC_REVERSE
2452 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2454 /* There are two cases where we currently need to step a
2455 breakpoint instruction when we have a signal to deliver:
2457 - See handle_signal_stop where we handle random signals that
2458 could take out us out of the stepping range. Normally, in
2459 that case we end up continuing (instead of stepping) over the
2460 signal handler with a breakpoint at PC, but there are cases
2461 where we should _always_ single-step, even if we have a
2462 step-resume breakpoint, like when a software watchpoint is
2463 set. Assuming single-stepping and delivering a signal at the
2464 same time would takes us to the signal handler, then we could
2465 have removed the breakpoint at PC to step over it. However,
2466 some hardware step targets (like e.g., Mac OS) can't step
2467 into signal handlers, and for those, we need to leave the
2468 breakpoint at PC inserted, as otherwise if the handler
2469 recurses and executes PC again, it'll miss the breakpoint.
2470 So we leave the breakpoint inserted anyway, but we need to
2471 record that we tried to step a breakpoint instruction, so
2472 that adjust_pc_after_break doesn't end up confused.
2474 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2475 in one thread after another thread that was stepping had been
2476 momentarily paused for a step-over. When we re-resume the
2477 stepping thread, it may be resumed from that address with a
2478 breakpoint that hasn't trapped yet. Seen with
2479 gdb.threads/non-stop-fair-events.exp, on targets that don't
2480 do displaced stepping. */
2482 infrun_debug_printf ("resume: [%s] stepped breakpoint",
2483 target_pid_to_str (tp
->ptid
).c_str ());
2485 tp
->stepped_breakpoint
= 1;
2487 /* Most targets can step a breakpoint instruction, thus
2488 executing it normally. But if this one cannot, just
2489 continue and we will hit it anyway. */
2490 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2495 && tp
->control
.trap_expected
2496 && use_displaced_stepping (tp
)
2497 && !step_over_info_valid_p ())
2499 struct regcache
*resume_regcache
= get_thread_regcache (tp
);
2500 struct gdbarch
*resume_gdbarch
= resume_regcache
->arch ();
2501 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2504 read_memory (actual_pc
, buf
, sizeof (buf
));
2505 displaced_debug_printf ("run %s: %s",
2506 paddress (resume_gdbarch
, actual_pc
),
2507 displaced_step_dump_bytes
2508 (buf
, sizeof (buf
)).c_str ());
2511 if (tp
->control
.may_range_step
)
2513 /* If we're resuming a thread with the PC out of the step
2514 range, then we're doing some nested/finer run control
2515 operation, like stepping the thread out of the dynamic
2516 linker or the displaced stepping scratch pad. We
2517 shouldn't have allowed a range step then. */
2518 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2521 do_target_resume (resume_ptid
, step
, sig
);
2522 tp
->set_resumed (true);
2525 /* Resume the inferior. SIG is the signal to give the inferior
2526 (GDB_SIGNAL_0 for none). This is a wrapper around 'resume_1' that
2527 rolls back state on error. */
2530 resume (gdb_signal sig
)
2536 catch (const gdb_exception
&ex
)
2538 /* If resuming is being aborted for any reason, delete any
2539 single-step breakpoint resume_1 may have created, to avoid
2540 confusing the following resumption, and to avoid leaving
2541 single-step breakpoints perturbing other threads, in case
2542 we're running in non-stop mode. */
2543 if (inferior_ptid
!= null_ptid
)
2544 delete_single_step_breakpoints (inferior_thread ());
2554 /* Counter that tracks number of user visible stops. This can be used
2555 to tell whether a command has proceeded the inferior past the
2556 current location. This allows e.g., inferior function calls in
2557 breakpoint commands to not interrupt the command list. When the
2558 call finishes successfully, the inferior is standing at the same
2559 breakpoint as if nothing happened (and so we don't call
2561 static ULONGEST current_stop_id
;
2568 return current_stop_id
;
2571 /* Called when we report a user visible stop. */
2579 /* Clear out all variables saying what to do when inferior is continued.
2580 First do this, then set the ones you want, then call `proceed'. */
2583 clear_proceed_status_thread (struct thread_info
*tp
)
2585 infrun_debug_printf ("%s", target_pid_to_str (tp
->ptid
).c_str ());
2587 /* If we're starting a new sequence, then the previous finished
2588 single-step is no longer relevant. */
2589 if (tp
->has_pending_waitstatus ())
2591 if (tp
->stop_reason () == TARGET_STOPPED_BY_SINGLE_STEP
)
2593 infrun_debug_printf ("pending event of %s was a finished step. "
2595 target_pid_to_str (tp
->ptid
).c_str ());
2597 tp
->clear_pending_waitstatus ();
2598 tp
->set_stop_reason (TARGET_STOPPED_BY_NO_REASON
);
2603 ("thread %s has pending wait status %s (currently_stepping=%d).",
2604 target_pid_to_str (tp
->ptid
).c_str (),
2605 target_waitstatus_to_string (&tp
->pending_waitstatus ()).c_str (),
2606 currently_stepping (tp
));
2610 /* If this signal should not be seen by program, give it zero.
2611 Used for debugging signals. */
2612 if (!signal_pass_state (tp
->stop_signal ()))
2613 tp
->set_stop_signal (GDB_SIGNAL_0
);
2615 delete tp
->thread_fsm
;
2616 tp
->thread_fsm
= NULL
;
2618 tp
->control
.trap_expected
= 0;
2619 tp
->control
.step_range_start
= 0;
2620 tp
->control
.step_range_end
= 0;
2621 tp
->control
.may_range_step
= 0;
2622 tp
->control
.step_frame_id
= null_frame_id
;
2623 tp
->control
.step_stack_frame_id
= null_frame_id
;
2624 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2625 tp
->control
.step_start_function
= NULL
;
2626 tp
->stop_requested
= 0;
2628 tp
->control
.stop_step
= 0;
2630 tp
->control
.proceed_to_finish
= 0;
2632 tp
->control
.stepping_command
= 0;
2634 /* Discard any remaining commands or status from previous stop. */
2635 bpstat_clear (&tp
->control
.stop_bpstat
);
2639 clear_proceed_status (int step
)
2641 /* With scheduler-locking replay, stop replaying other threads if we're
2642 not replaying the user-visible resume ptid.
2644 This is a convenience feature to not require the user to explicitly
2645 stop replaying the other threads. We're assuming that the user's
2646 intent is to resume tracing the recorded process. */
2647 if (!non_stop
&& scheduler_mode
== schedlock_replay
2648 && target_record_is_replaying (minus_one_ptid
)
2649 && !target_record_will_replay (user_visible_resume_ptid (step
),
2650 execution_direction
))
2651 target_record_stop_replaying ();
2653 if (!non_stop
&& inferior_ptid
!= null_ptid
)
2655 ptid_t resume_ptid
= user_visible_resume_ptid (step
);
2656 process_stratum_target
*resume_target
2657 = user_visible_resume_target (resume_ptid
);
2659 /* In all-stop mode, delete the per-thread status of all threads
2660 we're about to resume, implicitly and explicitly. */
2661 for (thread_info
*tp
: all_non_exited_threads (resume_target
, resume_ptid
))
2662 clear_proceed_status_thread (tp
);
2665 if (inferior_ptid
!= null_ptid
)
2667 struct inferior
*inferior
;
2671 /* If in non-stop mode, only delete the per-thread status of
2672 the current thread. */
2673 clear_proceed_status_thread (inferior_thread ());
2676 inferior
= current_inferior ();
2677 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2680 gdb::observers::about_to_proceed
.notify ();
2683 /* Returns true if TP is still stopped at a breakpoint that needs
2684 stepping-over in order to make progress. If the breakpoint is gone
2685 meanwhile, we can skip the whole step-over dance. */
2688 thread_still_needs_step_over_bp (struct thread_info
*tp
)
2690 if (tp
->stepping_over_breakpoint
)
2692 struct regcache
*regcache
= get_thread_regcache (tp
);
2694 if (breakpoint_here_p (regcache
->aspace (),
2695 regcache_read_pc (regcache
))
2696 == ordinary_breakpoint_here
)
2699 tp
->stepping_over_breakpoint
= 0;
2705 /* Check whether thread TP still needs to start a step-over in order
2706 to make progress when resumed. Returns an bitwise or of enum
2707 step_over_what bits, indicating what needs to be stepped over. */
2709 static step_over_what
2710 thread_still_needs_step_over (struct thread_info
*tp
)
2712 step_over_what what
= 0;
2714 if (thread_still_needs_step_over_bp (tp
))
2715 what
|= STEP_OVER_BREAKPOINT
;
2717 if (tp
->stepping_over_watchpoint
2718 && !target_have_steppable_watchpoint ())
2719 what
|= STEP_OVER_WATCHPOINT
;
2724 /* Returns true if scheduler locking applies. STEP indicates whether
2725 we're about to do a step/next-like command to a thread. */
2728 schedlock_applies (struct thread_info
*tp
)
2730 return (scheduler_mode
== schedlock_on
2731 || (scheduler_mode
== schedlock_step
2732 && tp
->control
.stepping_command
)
2733 || (scheduler_mode
== schedlock_replay
2734 && target_record_will_replay (minus_one_ptid
,
2735 execution_direction
)));
2738 /* Set process_stratum_target::COMMIT_RESUMED_STATE in all target
2739 stacks that have threads executing and don't have threads with
2743 maybe_set_commit_resumed_all_targets ()
2745 scoped_restore_current_thread restore_thread
;
2747 for (inferior
*inf
: all_non_exited_inferiors ())
2749 process_stratum_target
*proc_target
= inf
->process_target ();
2751 if (proc_target
->commit_resumed_state
)
2753 /* We already set this in a previous iteration, via another
2754 inferior sharing the process_stratum target. */
2758 /* If the target has no resumed threads, it would be useless to
2759 ask it to commit the resumed threads. */
2760 if (!proc_target
->threads_executing
)
2762 infrun_debug_printf ("not requesting commit-resumed for target "
2763 "%s, no resumed threads",
2764 proc_target
->shortname ());
2768 /* As an optimization, if a thread from this target has some
2769 status to report, handle it before requiring the target to
2770 commit its resumed threads: handling the status might lead to
2771 resuming more threads. */
2772 if (proc_target
->has_resumed_with_pending_wait_status ())
2774 infrun_debug_printf ("not requesting commit-resumed for target %s, a"
2775 " thread has a pending waitstatus",
2776 proc_target
->shortname ());
2780 switch_to_inferior_no_thread (inf
);
2782 if (target_has_pending_events ())
2784 infrun_debug_printf ("not requesting commit-resumed for target %s, "
2785 "target has pending events",
2786 proc_target
->shortname ());
2790 infrun_debug_printf ("enabling commit-resumed for target %s",
2791 proc_target
->shortname ());
2793 proc_target
->commit_resumed_state
= true;
2800 maybe_call_commit_resumed_all_targets ()
2802 scoped_restore_current_thread restore_thread
;
2804 for (inferior
*inf
: all_non_exited_inferiors ())
2806 process_stratum_target
*proc_target
= inf
->process_target ();
2808 if (!proc_target
->commit_resumed_state
)
2811 switch_to_inferior_no_thread (inf
);
2813 infrun_debug_printf ("calling commit_resumed for target %s",
2814 proc_target
->shortname());
2816 target_commit_resumed ();
2820 /* To track nesting of scoped_disable_commit_resumed objects, ensuring
2821 that only the outermost one attempts to re-enable
2823 static bool enable_commit_resumed
= true;
2827 scoped_disable_commit_resumed::scoped_disable_commit_resumed
2828 (const char *reason
)
2829 : m_reason (reason
),
2830 m_prev_enable_commit_resumed (enable_commit_resumed
)
2832 infrun_debug_printf ("reason=%s", m_reason
);
2834 enable_commit_resumed
= false;
2836 for (inferior
*inf
: all_non_exited_inferiors ())
2838 process_stratum_target
*proc_target
= inf
->process_target ();
2840 if (m_prev_enable_commit_resumed
)
2842 /* This is the outermost instance: force all
2843 COMMIT_RESUMED_STATE to false. */
2844 proc_target
->commit_resumed_state
= false;
2848 /* This is not the outermost instance, we expect
2849 COMMIT_RESUMED_STATE to have been cleared by the
2850 outermost instance. */
2851 gdb_assert (!proc_target
->commit_resumed_state
);
2859 scoped_disable_commit_resumed::reset ()
2865 infrun_debug_printf ("reason=%s", m_reason
);
2867 gdb_assert (!enable_commit_resumed
);
2869 enable_commit_resumed
= m_prev_enable_commit_resumed
;
2871 if (m_prev_enable_commit_resumed
)
2873 /* This is the outermost instance, re-enable
2874 COMMIT_RESUMED_STATE on the targets where it's possible. */
2875 maybe_set_commit_resumed_all_targets ();
2879 /* This is not the outermost instance, we expect
2880 COMMIT_RESUMED_STATE to still be false. */
2881 for (inferior
*inf
: all_non_exited_inferiors ())
2883 process_stratum_target
*proc_target
= inf
->process_target ();
2884 gdb_assert (!proc_target
->commit_resumed_state
);
2891 scoped_disable_commit_resumed::~scoped_disable_commit_resumed ()
2899 scoped_disable_commit_resumed::reset_and_commit ()
2902 maybe_call_commit_resumed_all_targets ();
2907 scoped_enable_commit_resumed::scoped_enable_commit_resumed
2908 (const char *reason
)
2909 : m_reason (reason
),
2910 m_prev_enable_commit_resumed (enable_commit_resumed
)
2912 infrun_debug_printf ("reason=%s", m_reason
);
2914 if (!enable_commit_resumed
)
2916 enable_commit_resumed
= true;
2918 /* Re-enable COMMIT_RESUMED_STATE on the targets where it's
2920 maybe_set_commit_resumed_all_targets ();
2922 maybe_call_commit_resumed_all_targets ();
2928 scoped_enable_commit_resumed::~scoped_enable_commit_resumed ()
2930 infrun_debug_printf ("reason=%s", m_reason
);
2932 gdb_assert (enable_commit_resumed
);
2934 enable_commit_resumed
= m_prev_enable_commit_resumed
;
2936 if (!enable_commit_resumed
)
2938 /* Force all COMMIT_RESUMED_STATE back to false. */
2939 for (inferior
*inf
: all_non_exited_inferiors ())
2941 process_stratum_target
*proc_target
= inf
->process_target ();
2942 proc_target
->commit_resumed_state
= false;
2947 /* Check that all the targets we're about to resume are in non-stop
2948 mode. Ideally, we'd only care whether all targets support
2949 target-async, but we're not there yet. E.g., stop_all_threads
2950 doesn't know how to handle all-stop targets. Also, the remote
2951 protocol in all-stop mode is synchronous, irrespective of
2952 target-async, which means that things like a breakpoint re-set
2953 triggered by one target would try to read memory from all targets
2957 check_multi_target_resumption (process_stratum_target
*resume_target
)
2959 if (!non_stop
&& resume_target
== nullptr)
2961 scoped_restore_current_thread restore_thread
;
2963 /* This is used to track whether we're resuming more than one
2965 process_stratum_target
*first_connection
= nullptr;
2967 /* The first inferior we see with a target that does not work in
2968 always-non-stop mode. */
2969 inferior
*first_not_non_stop
= nullptr;
2971 for (inferior
*inf
: all_non_exited_inferiors ())
2973 switch_to_inferior_no_thread (inf
);
2975 if (!target_has_execution ())
2978 process_stratum_target
*proc_target
2979 = current_inferior ()->process_target();
2981 if (!target_is_non_stop_p ())
2982 first_not_non_stop
= inf
;
2984 if (first_connection
== nullptr)
2985 first_connection
= proc_target
;
2986 else if (first_connection
!= proc_target
2987 && first_not_non_stop
!= nullptr)
2989 switch_to_inferior_no_thread (first_not_non_stop
);
2991 proc_target
= current_inferior ()->process_target();
2993 error (_("Connection %d (%s) does not support "
2994 "multi-target resumption."),
2995 proc_target
->connection_number
,
2996 make_target_connection_string (proc_target
).c_str ());
3002 /* Basic routine for continuing the program in various fashions.
3004 ADDR is the address to resume at, or -1 for resume where stopped.
3005 SIGGNAL is the signal to give it, or GDB_SIGNAL_0 for none,
3006 or GDB_SIGNAL_DEFAULT for act according to how it stopped.
3008 You should call clear_proceed_status before calling proceed. */
3011 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
)
3013 INFRUN_SCOPED_DEBUG_ENTER_EXIT
;
3015 struct regcache
*regcache
;
3016 struct gdbarch
*gdbarch
;
3018 struct execution_control_state ecss
;
3019 struct execution_control_state
*ecs
= &ecss
;
3022 /* If we're stopped at a fork/vfork, follow the branch set by the
3023 "set follow-fork-mode" command; otherwise, we'll just proceed
3024 resuming the current thread. */
3025 if (!follow_fork ())
3027 /* The target for some reason decided not to resume. */
3029 if (target_can_async_p ())
3030 inferior_event_handler (INF_EXEC_COMPLETE
);
3034 /* We'll update this if & when we switch to a new thread. */
3035 previous_inferior_ptid
= inferior_ptid
;
3037 regcache
= get_current_regcache ();
3038 gdbarch
= regcache
->arch ();
3039 const address_space
*aspace
= regcache
->aspace ();
3041 pc
= regcache_read_pc_protected (regcache
);
3043 thread_info
*cur_thr
= inferior_thread ();
3045 /* Fill in with reasonable starting values. */
3046 init_thread_stepping_state (cur_thr
);
3048 gdb_assert (!thread_is_in_step_over_chain (cur_thr
));
3051 = user_visible_resume_ptid (cur_thr
->control
.stepping_command
);
3052 process_stratum_target
*resume_target
3053 = user_visible_resume_target (resume_ptid
);
3055 check_multi_target_resumption (resume_target
);
3057 if (addr
== (CORE_ADDR
) -1)
3059 if (pc
== cur_thr
->stop_pc ()
3060 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
3061 && execution_direction
!= EXEC_REVERSE
)
3062 /* There is a breakpoint at the address we will resume at,
3063 step one instruction before inserting breakpoints so that
3064 we do not stop right away (and report a second hit at this
3067 Note, we don't do this in reverse, because we won't
3068 actually be executing the breakpoint insn anyway.
3069 We'll be (un-)executing the previous instruction. */
3070 cur_thr
->stepping_over_breakpoint
= 1;
3071 else if (gdbarch_single_step_through_delay_p (gdbarch
)
3072 && gdbarch_single_step_through_delay (gdbarch
,
3073 get_current_frame ()))
3074 /* We stepped onto an instruction that needs to be stepped
3075 again before re-inserting the breakpoint, do so. */
3076 cur_thr
->stepping_over_breakpoint
= 1;
3080 regcache_write_pc (regcache
, addr
);
3083 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
3084 cur_thr
->set_stop_signal (siggnal
);
3086 /* If an exception is thrown from this point on, make sure to
3087 propagate GDB's knowledge of the executing state to the
3088 frontend/user running state. */
3089 scoped_finish_thread_state
finish_state (resume_target
, resume_ptid
);
3091 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
3092 threads (e.g., we might need to set threads stepping over
3093 breakpoints first), from the user/frontend's point of view, all
3094 threads in RESUME_PTID are now running. Unless we're calling an
3095 inferior function, as in that case we pretend the inferior
3096 doesn't run at all. */
3097 if (!cur_thr
->control
.in_infcall
)
3098 set_running (resume_target
, resume_ptid
, true);
3100 infrun_debug_printf ("addr=%s, signal=%s", paddress (gdbarch
, addr
),
3101 gdb_signal_to_symbol_string (siggnal
));
3103 annotate_starting ();
3105 /* Make sure that output from GDB appears before output from the
3107 gdb_flush (gdb_stdout
);
3109 /* Since we've marked the inferior running, give it the terminal. A
3110 QUIT/Ctrl-C from here on is forwarded to the target (which can
3111 still detect attempts to unblock a stuck connection with repeated
3112 Ctrl-C from within target_pass_ctrlc). */
3113 target_terminal::inferior ();
3115 /* In a multi-threaded task we may select another thread and
3116 then continue or step.
3118 But if a thread that we're resuming had stopped at a breakpoint,
3119 it will immediately cause another breakpoint stop without any
3120 execution (i.e. it will report a breakpoint hit incorrectly). So
3121 we must step over it first.
3123 Look for threads other than the current (TP) that reported a
3124 breakpoint hit and haven't been resumed yet since. */
3126 /* If scheduler locking applies, we can avoid iterating over all
3128 if (!non_stop
&& !schedlock_applies (cur_thr
))
3130 for (thread_info
*tp
: all_non_exited_threads (resume_target
,
3133 switch_to_thread_no_regs (tp
);
3135 /* Ignore the current thread here. It's handled
3140 if (!thread_still_needs_step_over (tp
))
3143 gdb_assert (!thread_is_in_step_over_chain (tp
));
3145 infrun_debug_printf ("need to step-over [%s] first",
3146 target_pid_to_str (tp
->ptid
).c_str ());
3148 global_thread_step_over_chain_enqueue (tp
);
3151 switch_to_thread (cur_thr
);
3154 /* Enqueue the current thread last, so that we move all other
3155 threads over their breakpoints first. */
3156 if (cur_thr
->stepping_over_breakpoint
)
3157 global_thread_step_over_chain_enqueue (cur_thr
);
3159 /* If the thread isn't started, we'll still need to set its prev_pc,
3160 so that switch_back_to_stepped_thread knows the thread hasn't
3161 advanced. Must do this before resuming any thread, as in
3162 all-stop/remote, once we resume we can't send any other packet
3163 until the target stops again. */
3164 cur_thr
->prev_pc
= regcache_read_pc_protected (regcache
);
3167 scoped_disable_commit_resumed
disable_commit_resumed ("proceeding");
3169 started
= start_step_over ();
3171 if (step_over_info_valid_p ())
3173 /* Either this thread started a new in-line step over, or some
3174 other thread was already doing one. In either case, don't
3175 resume anything else until the step-over is finished. */
3177 else if (started
&& !target_is_non_stop_p ())
3179 /* A new displaced stepping sequence was started. In all-stop,
3180 we can't talk to the target anymore until it next stops. */
3182 else if (!non_stop
&& target_is_non_stop_p ())
3184 INFRUN_SCOPED_DEBUG_START_END
3185 ("resuming threads, all-stop-on-top-of-non-stop");
3187 /* In all-stop, but the target is always in non-stop mode.
3188 Start all other threads that are implicitly resumed too. */
3189 for (thread_info
*tp
: all_non_exited_threads (resume_target
,
3192 switch_to_thread_no_regs (tp
);
3194 if (!tp
->inf
->has_execution ())
3196 infrun_debug_printf ("[%s] target has no execution",
3197 target_pid_to_str (tp
->ptid
).c_str ());
3203 infrun_debug_printf ("[%s] resumed",
3204 target_pid_to_str (tp
->ptid
).c_str ());
3205 gdb_assert (tp
->executing
|| tp
->has_pending_waitstatus ());
3209 if (thread_is_in_step_over_chain (tp
))
3211 infrun_debug_printf ("[%s] needs step-over",
3212 target_pid_to_str (tp
->ptid
).c_str ());
3216 infrun_debug_printf ("resuming %s",
3217 target_pid_to_str (tp
->ptid
).c_str ());
3219 reset_ecs (ecs
, tp
);
3220 switch_to_thread (tp
);
3221 keep_going_pass_signal (ecs
);
3222 if (!ecs
->wait_some_more
)
3223 error (_("Command aborted."));
3226 else if (!cur_thr
->resumed () && !thread_is_in_step_over_chain (cur_thr
))
3228 /* The thread wasn't started, and isn't queued, run it now. */
3229 reset_ecs (ecs
, cur_thr
);
3230 switch_to_thread (cur_thr
);
3231 keep_going_pass_signal (ecs
);
3232 if (!ecs
->wait_some_more
)
3233 error (_("Command aborted."));
3236 disable_commit_resumed
.reset_and_commit ();
3239 finish_state
.release ();
3241 /* If we've switched threads above, switch back to the previously
3242 current thread. We don't want the user to see a different
3244 switch_to_thread (cur_thr
);
3246 /* Tell the event loop to wait for it to stop. If the target
3247 supports asynchronous execution, it'll do this from within
3249 if (!target_can_async_p ())
3250 mark_async_event_handler (infrun_async_inferior_event_token
);
3254 /* Start remote-debugging of a machine over a serial link. */
3257 start_remote (int from_tty
)
3259 inferior
*inf
= current_inferior ();
3260 inf
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
3262 /* Always go on waiting for the target, regardless of the mode. */
3263 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3264 indicate to wait_for_inferior that a target should timeout if
3265 nothing is returned (instead of just blocking). Because of this,
3266 targets expecting an immediate response need to, internally, set
3267 things up so that the target_wait() is forced to eventually
3269 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3270 differentiate to its caller what the state of the target is after
3271 the initial open has been performed. Here we're assuming that
3272 the target has stopped. It should be possible to eventually have
3273 target_open() return to the caller an indication that the target
3274 is currently running and GDB state should be set to the same as
3275 for an async run. */
3276 wait_for_inferior (inf
);
3278 /* Now that the inferior has stopped, do any bookkeeping like
3279 loading shared libraries. We want to do this before normal_stop,
3280 so that the displayed frame is up to date. */
3281 post_create_inferior (from_tty
);
3286 /* Initialize static vars when a new inferior begins. */
3289 init_wait_for_inferior (void)
3291 /* These are meaningless until the first time through wait_for_inferior. */
3293 breakpoint_init_inferior (inf_starting
);
3295 clear_proceed_status (0);
3297 nullify_last_target_wait_ptid ();
3299 previous_inferior_ptid
= inferior_ptid
;
3304 static void handle_inferior_event (struct execution_control_state
*ecs
);
3306 static void handle_step_into_function (struct gdbarch
*gdbarch
,
3307 struct execution_control_state
*ecs
);
3308 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
3309 struct execution_control_state
*ecs
);
3310 static void handle_signal_stop (struct execution_control_state
*ecs
);
3311 static void check_exception_resume (struct execution_control_state
*,
3312 struct frame_info
*);
3314 static void end_stepping_range (struct execution_control_state
*ecs
);
3315 static void stop_waiting (struct execution_control_state
*ecs
);
3316 static void keep_going (struct execution_control_state
*ecs
);
3317 static void process_event_stop_test (struct execution_control_state
*ecs
);
3318 static bool switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
3320 /* This function is attached as a "thread_stop_requested" observer.
3321 Cleanup local state that assumed the PTID was to be resumed, and
3322 report the stop to the frontend. */
3325 infrun_thread_stop_requested (ptid_t ptid
)
3327 process_stratum_target
*curr_target
= current_inferior ()->process_target ();
3329 /* PTID was requested to stop. If the thread was already stopped,
3330 but the user/frontend doesn't know about that yet (e.g., the
3331 thread had been temporarily paused for some step-over), set up
3332 for reporting the stop now. */
3333 for (thread_info
*tp
: all_threads (curr_target
, ptid
))
3335 if (tp
->state
!= THREAD_RUNNING
)
3340 /* Remove matching threads from the step-over queue, so
3341 start_step_over doesn't try to resume them
3343 if (thread_is_in_step_over_chain (tp
))
3344 global_thread_step_over_chain_remove (tp
);
3346 /* If the thread is stopped, but the user/frontend doesn't
3347 know about that yet, queue a pending event, as if the
3348 thread had just stopped now. Unless the thread already had
3350 if (!tp
->has_pending_waitstatus ())
3352 target_waitstatus ws
;
3353 ws
.kind
= TARGET_WAITKIND_STOPPED
;
3354 ws
.value
.sig
= GDB_SIGNAL_0
;
3355 tp
->set_pending_waitstatus (ws
);
3358 /* Clear the inline-frame state, since we're re-processing the
3360 clear_inline_frame_state (tp
);
3362 /* If this thread was paused because some other thread was
3363 doing an inline-step over, let that finish first. Once
3364 that happens, we'll restart all threads and consume pending
3365 stop events then. */
3366 if (step_over_info_valid_p ())
3369 /* Otherwise we can process the (new) pending event now. Set
3370 it so this pending event is considered by
3372 tp
->set_resumed (true);
3377 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
3379 if (target_last_proc_target
== tp
->inf
->process_target ()
3380 && target_last_wait_ptid
== tp
->ptid
)
3381 nullify_last_target_wait_ptid ();
3384 /* Delete the step resume, single-step and longjmp/exception resume
3385 breakpoints of TP. */
3388 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
3390 delete_step_resume_breakpoint (tp
);
3391 delete_exception_resume_breakpoint (tp
);
3392 delete_single_step_breakpoints (tp
);
3395 /* If the target still has execution, call FUNC for each thread that
3396 just stopped. In all-stop, that's all the non-exited threads; in
3397 non-stop, that's the current thread, only. */
3399 typedef void (*for_each_just_stopped_thread_callback_func
)
3400 (struct thread_info
*tp
);
3403 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
3405 if (!target_has_execution () || inferior_ptid
== null_ptid
)
3408 if (target_is_non_stop_p ())
3410 /* If in non-stop mode, only the current thread stopped. */
3411 func (inferior_thread ());
3415 /* In all-stop mode, all threads have stopped. */
3416 for (thread_info
*tp
: all_non_exited_threads ())
3421 /* Delete the step resume and longjmp/exception resume breakpoints of
3422 the threads that just stopped. */
3425 delete_just_stopped_threads_infrun_breakpoints (void)
3427 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3430 /* Delete the single-step breakpoints of the threads that just
3434 delete_just_stopped_threads_single_step_breakpoints (void)
3436 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3442 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3443 const struct target_waitstatus
*ws
)
3445 infrun_debug_printf ("target_wait (%s [%s], status) =",
3446 waiton_ptid
.to_string ().c_str (),
3447 target_pid_to_str (waiton_ptid
).c_str ());
3448 infrun_debug_printf (" %s [%s],",
3449 result_ptid
.to_string ().c_str (),
3450 target_pid_to_str (result_ptid
).c_str ());
3451 infrun_debug_printf (" %s", target_waitstatus_to_string (ws
).c_str ());
3454 /* Select a thread at random, out of those which are resumed and have
3457 static struct thread_info
*
3458 random_pending_event_thread (inferior
*inf
, ptid_t waiton_ptid
)
3460 process_stratum_target
*proc_target
= inf
->process_target ();
3462 = proc_target
->random_resumed_with_pending_wait_status (inf
, waiton_ptid
);
3464 if (thread
== nullptr)
3466 infrun_debug_printf ("None found.");
3470 infrun_debug_printf ("Found %s.", target_pid_to_str (thread
->ptid
).c_str ());
3471 gdb_assert (thread
->resumed ());
3472 gdb_assert (thread
->has_pending_waitstatus ());
3477 /* Wrapper for target_wait that first checks whether threads have
3478 pending statuses to report before actually asking the target for
3479 more events. INF is the inferior we're using to call target_wait
3483 do_target_wait_1 (inferior
*inf
, ptid_t ptid
,
3484 target_waitstatus
*status
, target_wait_flags options
)
3487 struct thread_info
*tp
;
3489 /* We know that we are looking for an event in the target of inferior
3490 INF, but we don't know which thread the event might come from. As
3491 such we want to make sure that INFERIOR_PTID is reset so that none of
3492 the wait code relies on it - doing so is always a mistake. */
3493 switch_to_inferior_no_thread (inf
);
3495 /* First check if there is a resumed thread with a wait status
3497 if (ptid
== minus_one_ptid
|| ptid
.is_pid ())
3499 tp
= random_pending_event_thread (inf
, ptid
);
3503 infrun_debug_printf ("Waiting for specific thread %s.",
3504 target_pid_to_str (ptid
).c_str ());
3506 /* We have a specific thread to check. */
3507 tp
= find_thread_ptid (inf
, ptid
);
3508 gdb_assert (tp
!= NULL
);
3509 if (!tp
->has_pending_waitstatus ())
3514 && (tp
->stop_reason () == TARGET_STOPPED_BY_SW_BREAKPOINT
3515 || tp
->stop_reason () == TARGET_STOPPED_BY_HW_BREAKPOINT
))
3517 struct regcache
*regcache
= get_thread_regcache (tp
);
3518 struct gdbarch
*gdbarch
= regcache
->arch ();
3522 pc
= regcache_read_pc (regcache
);
3524 if (pc
!= tp
->stop_pc ())
3526 infrun_debug_printf ("PC of %s changed. was=%s, now=%s",
3527 target_pid_to_str (tp
->ptid
).c_str (),
3528 paddress (gdbarch
, tp
->stop_pc ()),
3529 paddress (gdbarch
, pc
));
3532 else if (!breakpoint_inserted_here_p (regcache
->aspace (), pc
))
3534 infrun_debug_printf ("previous breakpoint of %s, at %s gone",
3535 target_pid_to_str (tp
->ptid
).c_str (),
3536 paddress (gdbarch
, pc
));
3543 infrun_debug_printf ("pending event of %s cancelled.",
3544 target_pid_to_str (tp
->ptid
).c_str ());
3546 tp
->clear_pending_waitstatus ();
3547 target_waitstatus ws
;
3548 ws
.kind
= TARGET_WAITKIND_SPURIOUS
;
3549 tp
->set_pending_waitstatus (ws
);
3550 tp
->set_stop_reason (TARGET_STOPPED_BY_NO_REASON
);
3556 infrun_debug_printf ("Using pending wait status %s for %s.",
3557 target_waitstatus_to_string
3558 (&tp
->pending_waitstatus ()).c_str (),
3559 target_pid_to_str (tp
->ptid
).c_str ());
3561 /* Now that we've selected our final event LWP, un-adjust its PC
3562 if it was a software breakpoint (and the target doesn't
3563 always adjust the PC itself). */
3564 if (tp
->stop_reason () == TARGET_STOPPED_BY_SW_BREAKPOINT
3565 && !target_supports_stopped_by_sw_breakpoint ())
3567 struct regcache
*regcache
;
3568 struct gdbarch
*gdbarch
;
3571 regcache
= get_thread_regcache (tp
);
3572 gdbarch
= regcache
->arch ();
3574 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3579 pc
= regcache_read_pc (regcache
);
3580 regcache_write_pc (regcache
, pc
+ decr_pc
);
3584 tp
->set_stop_reason (TARGET_STOPPED_BY_NO_REASON
);
3585 *status
= tp
->pending_waitstatus ();
3586 tp
->clear_pending_waitstatus ();
3588 /* Wake up the event loop again, until all pending events are
3590 if (target_is_async_p ())
3591 mark_async_event_handler (infrun_async_inferior_event_token
);
3595 /* But if we don't find one, we'll have to wait. */
3597 /* We can't ask a non-async target to do a non-blocking wait, so this will be
3599 if (!target_can_async_p ())
3600 options
&= ~TARGET_WNOHANG
;
3602 if (deprecated_target_wait_hook
)
3603 event_ptid
= deprecated_target_wait_hook (ptid
, status
, options
);
3605 event_ptid
= target_wait (ptid
, status
, options
);
3610 /* Wrapper for target_wait that first checks whether threads have
3611 pending statuses to report before actually asking the target for
3612 more events. Polls for events from all inferiors/targets. */
3615 do_target_wait (execution_control_state
*ecs
, target_wait_flags options
)
3617 int num_inferiors
= 0;
3618 int random_selector
;
3620 /* For fairness, we pick the first inferior/target to poll at random
3621 out of all inferiors that may report events, and then continue
3622 polling the rest of the inferior list starting from that one in a
3623 circular fashion until the whole list is polled once. */
3625 auto inferior_matches
= [] (inferior
*inf
)
3627 return inf
->process_target () != nullptr;
3630 /* First see how many matching inferiors we have. */
3631 for (inferior
*inf
: all_inferiors ())
3632 if (inferior_matches (inf
))
3635 if (num_inferiors
== 0)
3637 ecs
->ws
.kind
= TARGET_WAITKIND_IGNORE
;
3641 /* Now randomly pick an inferior out of those that matched. */
3642 random_selector
= (int)
3643 ((num_inferiors
* (double) rand ()) / (RAND_MAX
+ 1.0));
3645 if (num_inferiors
> 1)
3646 infrun_debug_printf ("Found %d inferiors, starting at #%d",
3647 num_inferiors
, random_selector
);
3649 /* Select the Nth inferior that matched. */
3651 inferior
*selected
= nullptr;
3653 for (inferior
*inf
: all_inferiors ())
3654 if (inferior_matches (inf
))
3655 if (random_selector
-- == 0)
3661 /* Now poll for events out of each of the matching inferior's
3662 targets, starting from the selected one. */
3664 auto do_wait
= [&] (inferior
*inf
)
3666 ecs
->ptid
= do_target_wait_1 (inf
, minus_one_ptid
, &ecs
->ws
, options
);
3667 ecs
->target
= inf
->process_target ();
3668 return (ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
);
3671 /* Needed in 'all-stop + target-non-stop' mode, because we end up
3672 here spuriously after the target is all stopped and we've already
3673 reported the stop to the user, polling for events. */
3674 scoped_restore_current_thread restore_thread
;
3676 intrusive_list_iterator
<inferior
> start
3677 = inferior_list
.iterator_to (*selected
);
3679 for (intrusive_list_iterator
<inferior
> it
= start
;
3680 it
!= inferior_list
.end ();
3683 inferior
*inf
= &*it
;
3685 if (inferior_matches (inf
) && do_wait (inf
))
3689 for (intrusive_list_iterator
<inferior
> it
= inferior_list
.begin ();
3693 inferior
*inf
= &*it
;
3695 if (inferior_matches (inf
) && do_wait (inf
))
3699 ecs
->ws
.kind
= TARGET_WAITKIND_IGNORE
;
3703 /* An event reported by wait_one. */
3705 struct wait_one_event
3707 /* The target the event came out of. */
3708 process_stratum_target
*target
;
3710 /* The PTID the event was for. */
3713 /* The waitstatus. */
3714 target_waitstatus ws
;
3717 static bool handle_one (const wait_one_event
&event
);
3718 static void restart_threads (struct thread_info
*event_thread
);
3720 /* Prepare and stabilize the inferior for detaching it. E.g.,
3721 detaching while a thread is displaced stepping is a recipe for
3722 crashing it, as nothing would readjust the PC out of the scratch
3726 prepare_for_detach (void)
3728 struct inferior
*inf
= current_inferior ();
3729 ptid_t pid_ptid
= ptid_t (inf
->pid
);
3730 scoped_restore_current_thread restore_thread
;
3732 scoped_restore restore_detaching
= make_scoped_restore (&inf
->detaching
, true);
3734 /* Remove all threads of INF from the global step-over chain. We
3735 want to stop any ongoing step-over, not start any new one. */
3736 thread_step_over_list_safe_range range
3737 = make_thread_step_over_list_safe_range (global_thread_step_over_list
);
3739 for (thread_info
*tp
: range
)
3742 infrun_debug_printf ("removing thread %s from global step over chain",
3743 target_pid_to_str (tp
->ptid
).c_str ());
3744 global_thread_step_over_chain_remove (tp
);
3747 /* If we were already in the middle of an inline step-over, and the
3748 thread stepping belongs to the inferior we're detaching, we need
3749 to restart the threads of other inferiors. */
3750 if (step_over_info
.thread
!= -1)
3752 infrun_debug_printf ("inline step-over in-process while detaching");
3754 thread_info
*thr
= find_thread_global_id (step_over_info
.thread
);
3755 if (thr
->inf
== inf
)
3757 /* Since we removed threads of INF from the step-over chain,
3758 we know this won't start a step-over for INF. */
3759 clear_step_over_info ();
3761 if (target_is_non_stop_p ())
3763 /* Start a new step-over in another thread if there's
3764 one that needs it. */
3767 /* Restart all other threads (except the
3768 previously-stepping thread, since that one is still
3770 if (!step_over_info_valid_p ())
3771 restart_threads (thr
);
3776 if (displaced_step_in_progress (inf
))
3778 infrun_debug_printf ("displaced-stepping in-process while detaching");
3780 /* Stop threads currently displaced stepping, aborting it. */
3782 for (thread_info
*thr
: inf
->non_exited_threads ())
3784 if (thr
->displaced_step_state
.in_progress ())
3788 if (!thr
->stop_requested
)
3790 target_stop (thr
->ptid
);
3791 thr
->stop_requested
= true;
3795 thr
->set_resumed (false);
3799 while (displaced_step_in_progress (inf
))
3801 wait_one_event event
;
3803 event
.target
= inf
->process_target ();
3804 event
.ptid
= do_target_wait_1 (inf
, pid_ptid
, &event
.ws
, 0);
3807 print_target_wait_results (pid_ptid
, event
.ptid
, &event
.ws
);
3812 /* It's OK to leave some of the threads of INF stopped, since
3813 they'll be detached shortly. */
3817 /* Wait for control to return from inferior to debugger.
3819 If inferior gets a signal, we may decide to start it up again
3820 instead of returning. That is why there is a loop in this function.
3821 When this function actually returns it means the inferior
3822 should be left stopped and GDB should read more commands. */
3825 wait_for_inferior (inferior
*inf
)
3827 infrun_debug_printf ("wait_for_inferior ()");
3829 SCOPE_EXIT
{ delete_just_stopped_threads_infrun_breakpoints (); };
3831 /* If an error happens while handling the event, propagate GDB's
3832 knowledge of the executing state to the frontend/user running
3834 scoped_finish_thread_state finish_state
3835 (inf
->process_target (), minus_one_ptid
);
3839 struct execution_control_state ecss
;
3840 struct execution_control_state
*ecs
= &ecss
;
3842 memset (ecs
, 0, sizeof (*ecs
));
3844 overlay_cache_invalid
= 1;
3846 /* Flush target cache before starting to handle each event.
3847 Target was running and cache could be stale. This is just a
3848 heuristic. Running threads may modify target memory, but we
3849 don't get any event. */
3850 target_dcache_invalidate ();
3852 ecs
->ptid
= do_target_wait_1 (inf
, minus_one_ptid
, &ecs
->ws
, 0);
3853 ecs
->target
= inf
->process_target ();
3856 print_target_wait_results (minus_one_ptid
, ecs
->ptid
, &ecs
->ws
);
3858 /* Now figure out what to do with the result of the result. */
3859 handle_inferior_event (ecs
);
3861 if (!ecs
->wait_some_more
)
3865 /* No error, don't finish the state yet. */
3866 finish_state
.release ();
3869 /* Cleanup that reinstalls the readline callback handler, if the
3870 target is running in the background. If while handling the target
3871 event something triggered a secondary prompt, like e.g., a
3872 pagination prompt, we'll have removed the callback handler (see
3873 gdb_readline_wrapper_line). Need to do this as we go back to the
3874 event loop, ready to process further input. Note this has no
3875 effect if the handler hasn't actually been removed, because calling
3876 rl_callback_handler_install resets the line buffer, thus losing
3880 reinstall_readline_callback_handler_cleanup ()
3882 struct ui
*ui
= current_ui
;
3886 /* We're not going back to the top level event loop yet. Don't
3887 install the readline callback, as it'd prep the terminal,
3888 readline-style (raw, noecho) (e.g., --batch). We'll install
3889 it the next time the prompt is displayed, when we're ready
3894 if (ui
->command_editing
&& ui
->prompt_state
!= PROMPT_BLOCKED
)
3895 gdb_rl_callback_handler_reinstall ();
3898 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3899 that's just the event thread. In all-stop, that's all threads. */
3902 clean_up_just_stopped_threads_fsms (struct execution_control_state
*ecs
)
3904 if (ecs
->event_thread
!= NULL
3905 && ecs
->event_thread
->thread_fsm
!= NULL
)
3906 ecs
->event_thread
->thread_fsm
->clean_up (ecs
->event_thread
);
3910 for (thread_info
*thr
: all_non_exited_threads ())
3912 if (thr
->thread_fsm
== NULL
)
3914 if (thr
== ecs
->event_thread
)
3917 switch_to_thread (thr
);
3918 thr
->thread_fsm
->clean_up (thr
);
3921 if (ecs
->event_thread
!= NULL
)
3922 switch_to_thread (ecs
->event_thread
);
3926 /* Helper for all_uis_check_sync_execution_done that works on the
3930 check_curr_ui_sync_execution_done (void)
3932 struct ui
*ui
= current_ui
;
3934 if (ui
->prompt_state
== PROMPT_NEEDED
3936 && !gdb_in_secondary_prompt_p (ui
))
3938 target_terminal::ours ();
3939 gdb::observers::sync_execution_done
.notify ();
3940 ui_register_input_event_handler (ui
);
3947 all_uis_check_sync_execution_done (void)
3949 SWITCH_THRU_ALL_UIS ()
3951 check_curr_ui_sync_execution_done ();
3958 all_uis_on_sync_execution_starting (void)
3960 SWITCH_THRU_ALL_UIS ()
3962 if (current_ui
->prompt_state
== PROMPT_NEEDED
)
3963 async_disable_stdin ();
3967 /* Asynchronous version of wait_for_inferior. It is called by the
3968 event loop whenever a change of state is detected on the file
3969 descriptor corresponding to the target. It can be called more than
3970 once to complete a single execution command. In such cases we need
3971 to keep the state in a global variable ECSS. If it is the last time
3972 that this function is called for a single execution command, then
3973 report to the user that the inferior has stopped, and do the
3974 necessary cleanups. */
3977 fetch_inferior_event ()
3979 INFRUN_SCOPED_DEBUG_ENTER_EXIT
;
3981 struct execution_control_state ecss
;
3982 struct execution_control_state
*ecs
= &ecss
;
3985 memset (ecs
, 0, sizeof (*ecs
));
3987 /* Events are always processed with the main UI as current UI. This
3988 way, warnings, debug output, etc. are always consistently sent to
3989 the main console. */
3990 scoped_restore save_ui
= make_scoped_restore (¤t_ui
, main_ui
);
3992 /* Temporarily disable pagination. Otherwise, the user would be
3993 given an option to press 'q' to quit, which would cause an early
3994 exit and could leave GDB in a half-baked state. */
3995 scoped_restore save_pagination
3996 = make_scoped_restore (&pagination_enabled
, false);
3998 /* End up with readline processing input, if necessary. */
4000 SCOPE_EXIT
{ reinstall_readline_callback_handler_cleanup (); };
4002 /* We're handling a live event, so make sure we're doing live
4003 debugging. If we're looking at traceframes while the target is
4004 running, we're going to need to get back to that mode after
4005 handling the event. */
4006 gdb::optional
<scoped_restore_current_traceframe
> maybe_restore_traceframe
;
4009 maybe_restore_traceframe
.emplace ();
4010 set_current_traceframe (-1);
4013 /* The user/frontend should not notice a thread switch due to
4014 internal events. Make sure we revert to the user selected
4015 thread and frame after handling the event and running any
4016 breakpoint commands. */
4017 scoped_restore_current_thread restore_thread
;
4019 overlay_cache_invalid
= 1;
4020 /* Flush target cache before starting to handle each event. Target
4021 was running and cache could be stale. This is just a heuristic.
4022 Running threads may modify target memory, but we don't get any
4024 target_dcache_invalidate ();
4026 scoped_restore save_exec_dir
4027 = make_scoped_restore (&execution_direction
,
4028 target_execution_direction ());
4030 /* Allow targets to pause their resumed threads while we handle
4032 scoped_disable_commit_resumed
disable_commit_resumed ("handling event");
4034 if (!do_target_wait (ecs
, TARGET_WNOHANG
))
4036 infrun_debug_printf ("do_target_wait returned no event");
4037 disable_commit_resumed
.reset_and_commit ();
4041 gdb_assert (ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
);
4043 /* Switch to the target that generated the event, so we can do
4045 switch_to_target_no_thread (ecs
->target
);
4048 print_target_wait_results (minus_one_ptid
, ecs
->ptid
, &ecs
->ws
);
4050 /* If an error happens while handling the event, propagate GDB's
4051 knowledge of the executing state to the frontend/user running
4053 ptid_t finish_ptid
= !target_is_non_stop_p () ? minus_one_ptid
: ecs
->ptid
;
4054 scoped_finish_thread_state
finish_state (ecs
->target
, finish_ptid
);
4056 /* Get executed before scoped_restore_current_thread above to apply
4057 still for the thread which has thrown the exception. */
4058 auto defer_bpstat_clear
4059 = make_scope_exit (bpstat_clear_actions
);
4060 auto defer_delete_threads
4061 = make_scope_exit (delete_just_stopped_threads_infrun_breakpoints
);
4063 /* Now figure out what to do with the result of the result. */
4064 handle_inferior_event (ecs
);
4066 if (!ecs
->wait_some_more
)
4068 struct inferior
*inf
= find_inferior_ptid (ecs
->target
, ecs
->ptid
);
4069 bool should_stop
= true;
4070 struct thread_info
*thr
= ecs
->event_thread
;
4072 delete_just_stopped_threads_infrun_breakpoints ();
4076 struct thread_fsm
*thread_fsm
= thr
->thread_fsm
;
4078 if (thread_fsm
!= NULL
)
4079 should_stop
= thread_fsm
->should_stop (thr
);
4088 bool should_notify_stop
= true;
4091 clean_up_just_stopped_threads_fsms (ecs
);
4093 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
4094 should_notify_stop
= thr
->thread_fsm
->should_notify_stop ();
4096 if (should_notify_stop
)
4098 /* We may not find an inferior if this was a process exit. */
4099 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
4100 proceeded
= normal_stop ();
4105 inferior_event_handler (INF_EXEC_COMPLETE
);
4109 /* If we got a TARGET_WAITKIND_NO_RESUMED event, then the
4110 previously selected thread is gone. We have two
4111 choices - switch to no thread selected, or restore the
4112 previously selected thread (now exited). We chose the
4113 later, just because that's what GDB used to do. After
4114 this, "info threads" says "The current thread <Thread
4115 ID 2> has terminated." instead of "No thread
4119 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
4120 restore_thread
.dont_restore ();
4124 defer_delete_threads
.release ();
4125 defer_bpstat_clear
.release ();
4127 /* No error, don't finish the thread states yet. */
4128 finish_state
.release ();
4130 disable_commit_resumed
.reset_and_commit ();
4132 /* This scope is used to ensure that readline callbacks are
4133 reinstalled here. */
4136 /* If a UI was in sync execution mode, and now isn't, restore its
4137 prompt (a synchronous execution command has finished, and we're
4138 ready for input). */
4139 all_uis_check_sync_execution_done ();
4142 && exec_done_display_p
4143 && (inferior_ptid
== null_ptid
4144 || inferior_thread ()->state
!= THREAD_RUNNING
))
4145 printf_unfiltered (_("completed.\n"));
4151 set_step_info (thread_info
*tp
, struct frame_info
*frame
,
4152 struct symtab_and_line sal
)
4154 /* This can be removed once this function no longer implicitly relies on the
4155 inferior_ptid value. */
4156 gdb_assert (inferior_ptid
== tp
->ptid
);
4158 tp
->control
.step_frame_id
= get_frame_id (frame
);
4159 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
4161 tp
->current_symtab
= sal
.symtab
;
4162 tp
->current_line
= sal
.line
;
4165 /* Clear context switchable stepping state. */
4168 init_thread_stepping_state (struct thread_info
*tss
)
4170 tss
->stepped_breakpoint
= 0;
4171 tss
->stepping_over_breakpoint
= 0;
4172 tss
->stepping_over_watchpoint
= 0;
4173 tss
->step_after_step_resume_breakpoint
= 0;
4179 set_last_target_status (process_stratum_target
*target
, ptid_t ptid
,
4180 target_waitstatus status
)
4182 target_last_proc_target
= target
;
4183 target_last_wait_ptid
= ptid
;
4184 target_last_waitstatus
= status
;
4190 get_last_target_status (process_stratum_target
**target
, ptid_t
*ptid
,
4191 target_waitstatus
*status
)
4193 if (target
!= nullptr)
4194 *target
= target_last_proc_target
;
4195 if (ptid
!= nullptr)
4196 *ptid
= target_last_wait_ptid
;
4197 if (status
!= nullptr)
4198 *status
= target_last_waitstatus
;
4204 nullify_last_target_wait_ptid (void)
4206 target_last_proc_target
= nullptr;
4207 target_last_wait_ptid
= minus_one_ptid
;
4208 target_last_waitstatus
= {};
4211 /* Switch thread contexts. */
4214 context_switch (execution_control_state
*ecs
)
4216 if (ecs
->ptid
!= inferior_ptid
4217 && (inferior_ptid
== null_ptid
4218 || ecs
->event_thread
!= inferior_thread ()))
4220 infrun_debug_printf ("Switching context from %s to %s",
4221 target_pid_to_str (inferior_ptid
).c_str (),
4222 target_pid_to_str (ecs
->ptid
).c_str ());
4225 switch_to_thread (ecs
->event_thread
);
4228 /* If the target can't tell whether we've hit breakpoints
4229 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
4230 check whether that could have been caused by a breakpoint. If so,
4231 adjust the PC, per gdbarch_decr_pc_after_break. */
4234 adjust_pc_after_break (struct thread_info
*thread
,
4235 const target_waitstatus
*ws
)
4237 struct regcache
*regcache
;
4238 struct gdbarch
*gdbarch
;
4239 CORE_ADDR breakpoint_pc
, decr_pc
;
4241 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
4242 we aren't, just return.
4244 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
4245 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
4246 implemented by software breakpoints should be handled through the normal
4249 NOTE drow/2004-01-31: On some targets, breakpoints may generate
4250 different signals (SIGILL or SIGEMT for instance), but it is less
4251 clear where the PC is pointing afterwards. It may not match
4252 gdbarch_decr_pc_after_break. I don't know any specific target that
4253 generates these signals at breakpoints (the code has been in GDB since at
4254 least 1992) so I can not guess how to handle them here.
4256 In earlier versions of GDB, a target with
4257 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
4258 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
4259 target with both of these set in GDB history, and it seems unlikely to be
4260 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
4262 if (ws
->kind
!= TARGET_WAITKIND_STOPPED
)
4265 if (ws
->value
.sig
!= GDB_SIGNAL_TRAP
)
4268 /* In reverse execution, when a breakpoint is hit, the instruction
4269 under it has already been de-executed. The reported PC always
4270 points at the breakpoint address, so adjusting it further would
4271 be wrong. E.g., consider this case on a decr_pc_after_break == 1
4274 B1 0x08000000 : INSN1
4275 B2 0x08000001 : INSN2
4277 PC -> 0x08000003 : INSN4
4279 Say you're stopped at 0x08000003 as above. Reverse continuing
4280 from that point should hit B2 as below. Reading the PC when the
4281 SIGTRAP is reported should read 0x08000001 and INSN2 should have
4282 been de-executed already.
4284 B1 0x08000000 : INSN1
4285 B2 PC -> 0x08000001 : INSN2
4289 We can't apply the same logic as for forward execution, because
4290 we would wrongly adjust the PC to 0x08000000, since there's a
4291 breakpoint at PC - 1. We'd then report a hit on B1, although
4292 INSN1 hadn't been de-executed yet. Doing nothing is the correct
4294 if (execution_direction
== EXEC_REVERSE
)
4297 /* If the target can tell whether the thread hit a SW breakpoint,
4298 trust it. Targets that can tell also adjust the PC
4300 if (target_supports_stopped_by_sw_breakpoint ())
4303 /* Note that relying on whether a breakpoint is planted in memory to
4304 determine this can fail. E.g,. the breakpoint could have been
4305 removed since. Or the thread could have been told to step an
4306 instruction the size of a breakpoint instruction, and only
4307 _after_ was a breakpoint inserted at its address. */
4309 /* If this target does not decrement the PC after breakpoints, then
4310 we have nothing to do. */
4311 regcache
= get_thread_regcache (thread
);
4312 gdbarch
= regcache
->arch ();
4314 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
4318 const address_space
*aspace
= regcache
->aspace ();
4320 /* Find the location where (if we've hit a breakpoint) the
4321 breakpoint would be. */
4322 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
4324 /* If the target can't tell whether a software breakpoint triggered,
4325 fallback to figuring it out based on breakpoints we think were
4326 inserted in the target, and on whether the thread was stepped or
4329 /* Check whether there actually is a software breakpoint inserted at
4332 If in non-stop mode, a race condition is possible where we've
4333 removed a breakpoint, but stop events for that breakpoint were
4334 already queued and arrive later. To suppress those spurious
4335 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
4336 and retire them after a number of stop events are reported. Note
4337 this is an heuristic and can thus get confused. The real fix is
4338 to get the "stopped by SW BP and needs adjustment" info out of
4339 the target/kernel (and thus never reach here; see above). */
4340 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
4341 || (target_is_non_stop_p ()
4342 && moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
4344 gdb::optional
<scoped_restore_tmpl
<int>> restore_operation_disable
;
4346 if (record_full_is_used ())
4347 restore_operation_disable
.emplace
4348 (record_full_gdb_operation_disable_set ());
4350 /* When using hardware single-step, a SIGTRAP is reported for both
4351 a completed single-step and a software breakpoint. Need to
4352 differentiate between the two, as the latter needs adjusting
4353 but the former does not.
4355 The SIGTRAP can be due to a completed hardware single-step only if
4356 - we didn't insert software single-step breakpoints
4357 - this thread is currently being stepped
4359 If any of these events did not occur, we must have stopped due
4360 to hitting a software breakpoint, and have to back up to the
4363 As a special case, we could have hardware single-stepped a
4364 software breakpoint. In this case (prev_pc == breakpoint_pc),
4365 we also need to back up to the breakpoint address. */
4367 if (thread_has_single_step_breakpoints_set (thread
)
4368 || !currently_stepping (thread
)
4369 || (thread
->stepped_breakpoint
4370 && thread
->prev_pc
== breakpoint_pc
))
4371 regcache_write_pc (regcache
, breakpoint_pc
);
4376 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
4378 for (frame
= get_prev_frame (frame
);
4380 frame
= get_prev_frame (frame
))
4382 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
4385 if (get_frame_type (frame
) != INLINE_FRAME
)
4392 /* Look for an inline frame that is marked for skip.
4393 If PREV_FRAME is TRUE start at the previous frame,
4394 otherwise start at the current frame. Stop at the
4395 first non-inline frame, or at the frame where the
4399 inline_frame_is_marked_for_skip (bool prev_frame
, struct thread_info
*tp
)
4401 struct frame_info
*frame
= get_current_frame ();
4404 frame
= get_prev_frame (frame
);
4406 for (; frame
!= NULL
; frame
= get_prev_frame (frame
))
4408 const char *fn
= NULL
;
4409 symtab_and_line sal
;
4412 if (frame_id_eq (get_frame_id (frame
), tp
->control
.step_frame_id
))
4414 if (get_frame_type (frame
) != INLINE_FRAME
)
4417 sal
= find_frame_sal (frame
);
4418 sym
= get_frame_function (frame
);
4421 fn
= sym
->print_name ();
4424 && function_name_is_marked_for_skip (fn
, sal
))
4431 /* If the event thread has the stop requested flag set, pretend it
4432 stopped for a GDB_SIGNAL_0 (i.e., as if it stopped due to
4436 handle_stop_requested (struct execution_control_state
*ecs
)
4438 if (ecs
->event_thread
->stop_requested
)
4440 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
4441 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
4442 handle_signal_stop (ecs
);
4448 /* Auxiliary function that handles syscall entry/return events.
4449 It returns true if the inferior should keep going (and GDB
4450 should ignore the event), or false if the event deserves to be
4454 handle_syscall_event (struct execution_control_state
*ecs
)
4456 struct regcache
*regcache
;
4459 context_switch (ecs
);
4461 regcache
= get_thread_regcache (ecs
->event_thread
);
4462 syscall_number
= ecs
->ws
.value
.syscall_number
;
4463 ecs
->event_thread
->set_stop_pc (regcache_read_pc (regcache
));
4465 if (catch_syscall_enabled () > 0
4466 && catching_syscall_number (syscall_number
) > 0)
4468 infrun_debug_printf ("syscall number=%d", syscall_number
);
4470 ecs
->event_thread
->control
.stop_bpstat
4471 = bpstat_stop_status (regcache
->aspace (),
4472 ecs
->event_thread
->stop_pc (),
4473 ecs
->event_thread
, &ecs
->ws
);
4475 if (handle_stop_requested (ecs
))
4478 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4480 /* Catchpoint hit. */
4485 if (handle_stop_requested (ecs
))
4488 /* If no catchpoint triggered for this, then keep going. */
4494 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4497 fill_in_stop_func (struct gdbarch
*gdbarch
,
4498 struct execution_control_state
*ecs
)
4500 if (!ecs
->stop_func_filled_in
)
4503 const general_symbol_info
*gsi
;
4505 /* Don't care about return value; stop_func_start and stop_func_name
4506 will both be 0 if it doesn't work. */
4507 find_pc_partial_function_sym (ecs
->event_thread
->stop_pc (),
4509 &ecs
->stop_func_start
,
4510 &ecs
->stop_func_end
,
4512 ecs
->stop_func_name
= gsi
== nullptr ? nullptr : gsi
->print_name ();
4514 /* The call to find_pc_partial_function, above, will set
4515 stop_func_start and stop_func_end to the start and end
4516 of the range containing the stop pc. If this range
4517 contains the entry pc for the block (which is always the
4518 case for contiguous blocks), advance stop_func_start past
4519 the function's start offset and entrypoint. Note that
4520 stop_func_start is NOT advanced when in a range of a
4521 non-contiguous block that does not contain the entry pc. */
4522 if (block
!= nullptr
4523 && ecs
->stop_func_start
<= BLOCK_ENTRY_PC (block
)
4524 && BLOCK_ENTRY_PC (block
) < ecs
->stop_func_end
)
4526 ecs
->stop_func_start
4527 += gdbarch_deprecated_function_start_offset (gdbarch
);
4529 if (gdbarch_skip_entrypoint_p (gdbarch
))
4530 ecs
->stop_func_start
4531 = gdbarch_skip_entrypoint (gdbarch
, ecs
->stop_func_start
);
4534 ecs
->stop_func_filled_in
= 1;
4539 /* Return the STOP_SOON field of the inferior pointed at by ECS. */
4541 static enum stop_kind
4542 get_inferior_stop_soon (execution_control_state
*ecs
)
4544 struct inferior
*inf
= find_inferior_ptid (ecs
->target
, ecs
->ptid
);
4546 gdb_assert (inf
!= NULL
);
4547 return inf
->control
.stop_soon
;
4550 /* Poll for one event out of the current target. Store the resulting
4551 waitstatus in WS, and return the event ptid. Does not block. */
4554 poll_one_curr_target (struct target_waitstatus
*ws
)
4558 overlay_cache_invalid
= 1;
4560 /* Flush target cache before starting to handle each event.
4561 Target was running and cache could be stale. This is just a
4562 heuristic. Running threads may modify target memory, but we
4563 don't get any event. */
4564 target_dcache_invalidate ();
4566 if (deprecated_target_wait_hook
)
4567 event_ptid
= deprecated_target_wait_hook (minus_one_ptid
, ws
, TARGET_WNOHANG
);
4569 event_ptid
= target_wait (minus_one_ptid
, ws
, TARGET_WNOHANG
);
4572 print_target_wait_results (minus_one_ptid
, event_ptid
, ws
);
4577 /* Wait for one event out of any target. */
4579 static wait_one_event
4584 for (inferior
*inf
: all_inferiors ())
4586 process_stratum_target
*target
= inf
->process_target ();
4588 || !target
->is_async_p ()
4589 || !target
->threads_executing
)
4592 switch_to_inferior_no_thread (inf
);
4594 wait_one_event event
;
4595 event
.target
= target
;
4596 event
.ptid
= poll_one_curr_target (&event
.ws
);
4598 if (event
.ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4600 /* If nothing is resumed, remove the target from the
4604 else if (event
.ws
.kind
!= TARGET_WAITKIND_IGNORE
)
4608 /* Block waiting for some event. */
4615 for (inferior
*inf
: all_inferiors ())
4617 process_stratum_target
*target
= inf
->process_target ();
4619 || !target
->is_async_p ()
4620 || !target
->threads_executing
)
4623 int fd
= target
->async_wait_fd ();
4624 FD_SET (fd
, &readfds
);
4631 /* No waitable targets left. All must be stopped. */
4632 return {NULL
, minus_one_ptid
, {TARGET_WAITKIND_NO_RESUMED
}};
4637 int numfds
= interruptible_select (nfds
, &readfds
, 0, NULL
, 0);
4643 perror_with_name ("interruptible_select");
4648 /* Save the thread's event and stop reason to process it later. */
4651 save_waitstatus (struct thread_info
*tp
, const target_waitstatus
*ws
)
4653 infrun_debug_printf ("saving status %s for %d.%ld.%ld",
4654 target_waitstatus_to_string (ws
).c_str (),
4659 /* Record for later. */
4660 tp
->set_pending_waitstatus (*ws
);
4662 if (ws
->kind
== TARGET_WAITKIND_STOPPED
4663 && ws
->value
.sig
== GDB_SIGNAL_TRAP
)
4665 struct regcache
*regcache
= get_thread_regcache (tp
);
4666 const address_space
*aspace
= regcache
->aspace ();
4667 CORE_ADDR pc
= regcache_read_pc (regcache
);
4669 adjust_pc_after_break (tp
, &tp
->pending_waitstatus ());
4671 scoped_restore_current_thread restore_thread
;
4672 switch_to_thread (tp
);
4674 if (target_stopped_by_watchpoint ())
4675 tp
->set_stop_reason (TARGET_STOPPED_BY_WATCHPOINT
);
4676 else if (target_supports_stopped_by_sw_breakpoint ()
4677 && target_stopped_by_sw_breakpoint ())
4678 tp
->set_stop_reason (TARGET_STOPPED_BY_SW_BREAKPOINT
);
4679 else if (target_supports_stopped_by_hw_breakpoint ()
4680 && target_stopped_by_hw_breakpoint ())
4681 tp
->set_stop_reason (TARGET_STOPPED_BY_HW_BREAKPOINT
);
4682 else if (!target_supports_stopped_by_hw_breakpoint ()
4683 && hardware_breakpoint_inserted_here_p (aspace
, pc
))
4684 tp
->set_stop_reason (TARGET_STOPPED_BY_HW_BREAKPOINT
);
4685 else if (!target_supports_stopped_by_sw_breakpoint ()
4686 && software_breakpoint_inserted_here_p (aspace
, pc
))
4687 tp
->set_stop_reason (TARGET_STOPPED_BY_SW_BREAKPOINT
);
4688 else if (!thread_has_single_step_breakpoints_set (tp
)
4689 && currently_stepping (tp
))
4690 tp
->set_stop_reason (TARGET_STOPPED_BY_SINGLE_STEP
);
4694 /* Mark the non-executing threads accordingly. In all-stop, all
4695 threads of all processes are stopped when we get any event
4696 reported. In non-stop mode, only the event thread stops. */
4699 mark_non_executing_threads (process_stratum_target
*target
,
4701 struct target_waitstatus ws
)
4705 if (!target_is_non_stop_p ())
4706 mark_ptid
= minus_one_ptid
;
4707 else if (ws
.kind
== TARGET_WAITKIND_SIGNALLED
4708 || ws
.kind
== TARGET_WAITKIND_EXITED
)
4710 /* If we're handling a process exit in non-stop mode, even
4711 though threads haven't been deleted yet, one would think
4712 that there is nothing to do, as threads of the dead process
4713 will be soon deleted, and threads of any other process were
4714 left running. However, on some targets, threads survive a
4715 process exit event. E.g., for the "checkpoint" command,
4716 when the current checkpoint/fork exits, linux-fork.c
4717 automatically switches to another fork from within
4718 target_mourn_inferior, by associating the same
4719 inferior/thread to another fork. We haven't mourned yet at
4720 this point, but we must mark any threads left in the
4721 process as not-executing so that finish_thread_state marks
4722 them stopped (in the user's perspective) if/when we present
4723 the stop to the user. */
4724 mark_ptid
= ptid_t (event_ptid
.pid ());
4727 mark_ptid
= event_ptid
;
4729 set_executing (target
, mark_ptid
, false);
4731 /* Likewise the resumed flag. */
4732 set_resumed (target
, mark_ptid
, false);
4735 /* Handle one event after stopping threads. If the eventing thread
4736 reports back any interesting event, we leave it pending. If the
4737 eventing thread was in the middle of a displaced step, we
4738 cancel/finish it, and unless the thread's inferior is being
4739 detached, put the thread back in the step-over chain. Returns true
4740 if there are no resumed threads left in the target (thus there's no
4741 point in waiting further), false otherwise. */
4744 handle_one (const wait_one_event
&event
)
4747 ("%s %s", target_waitstatus_to_string (&event
.ws
).c_str (),
4748 target_pid_to_str (event
.ptid
).c_str ());
4750 if (event
.ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4752 /* All resumed threads exited. */
4755 else if (event
.ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
4756 || event
.ws
.kind
== TARGET_WAITKIND_EXITED
4757 || event
.ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
4759 /* One thread/process exited/signalled. */
4761 thread_info
*t
= nullptr;
4763 /* The target may have reported just a pid. If so, try
4764 the first non-exited thread. */
4765 if (event
.ptid
.is_pid ())
4767 int pid
= event
.ptid
.pid ();
4768 inferior
*inf
= find_inferior_pid (event
.target
, pid
);
4769 for (thread_info
*tp
: inf
->non_exited_threads ())
4775 /* If there is no available thread, the event would
4776 have to be appended to a per-inferior event list,
4777 which does not exist (and if it did, we'd have
4778 to adjust run control command to be able to
4779 resume such an inferior). We assert here instead
4780 of going into an infinite loop. */
4781 gdb_assert (t
!= nullptr);
4784 ("using %s", target_pid_to_str (t
->ptid
).c_str ());
4788 t
= find_thread_ptid (event
.target
, event
.ptid
);
4789 /* Check if this is the first time we see this thread.
4790 Don't bother adding if it individually exited. */
4792 && event
.ws
.kind
!= TARGET_WAITKIND_THREAD_EXITED
)
4793 t
= add_thread (event
.target
, event
.ptid
);
4798 /* Set the threads as non-executing to avoid
4799 another stop attempt on them. */
4800 switch_to_thread_no_regs (t
);
4801 mark_non_executing_threads (event
.target
, event
.ptid
,
4803 save_waitstatus (t
, &event
.ws
);
4804 t
->stop_requested
= false;
4809 thread_info
*t
= find_thread_ptid (event
.target
, event
.ptid
);
4811 t
= add_thread (event
.target
, event
.ptid
);
4813 t
->stop_requested
= 0;
4815 t
->set_resumed (false);
4816 t
->control
.may_range_step
= 0;
4818 /* This may be the first time we see the inferior report
4820 inferior
*inf
= find_inferior_ptid (event
.target
, event
.ptid
);
4821 if (inf
->needs_setup
)
4823 switch_to_thread_no_regs (t
);
4827 if (event
.ws
.kind
== TARGET_WAITKIND_STOPPED
4828 && event
.ws
.value
.sig
== GDB_SIGNAL_0
)
4830 /* We caught the event that we intended to catch, so
4831 there's no event to save as pending. */
4833 if (displaced_step_finish (t
, GDB_SIGNAL_0
)
4834 == DISPLACED_STEP_FINISH_STATUS_NOT_EXECUTED
)
4836 /* Add it back to the step-over queue. */
4838 ("displaced-step of %s canceled",
4839 target_pid_to_str (t
->ptid
).c_str ());
4841 t
->control
.trap_expected
= 0;
4842 if (!t
->inf
->detaching
)
4843 global_thread_step_over_chain_enqueue (t
);
4848 enum gdb_signal sig
;
4849 struct regcache
*regcache
;
4852 ("target_wait %s, saving status for %d.%ld.%ld",
4853 target_waitstatus_to_string (&event
.ws
).c_str (),
4854 t
->ptid
.pid (), t
->ptid
.lwp (), t
->ptid
.tid ());
4856 /* Record for later. */
4857 save_waitstatus (t
, &event
.ws
);
4859 sig
= (event
.ws
.kind
== TARGET_WAITKIND_STOPPED
4860 ? event
.ws
.value
.sig
: GDB_SIGNAL_0
);
4862 if (displaced_step_finish (t
, sig
)
4863 == DISPLACED_STEP_FINISH_STATUS_NOT_EXECUTED
)
4865 /* Add it back to the step-over queue. */
4866 t
->control
.trap_expected
= 0;
4867 if (!t
->inf
->detaching
)
4868 global_thread_step_over_chain_enqueue (t
);
4871 regcache
= get_thread_regcache (t
);
4872 t
->set_stop_pc (regcache_read_pc (regcache
));
4874 infrun_debug_printf ("saved stop_pc=%s for %s "
4875 "(currently_stepping=%d)",
4876 paddress (target_gdbarch (), t
->stop_pc ()),
4877 target_pid_to_str (t
->ptid
).c_str (),
4878 currently_stepping (t
));
4888 stop_all_threads (void)
4890 /* We may need multiple passes to discover all threads. */
4894 gdb_assert (exists_non_stop_target ());
4896 infrun_debug_printf ("starting");
4898 scoped_restore_current_thread restore_thread
;
4900 /* Enable thread events of all targets. */
4901 for (auto *target
: all_non_exited_process_targets ())
4903 switch_to_target_no_thread (target
);
4904 target_thread_events (true);
4909 /* Disable thread events of all targets. */
4910 for (auto *target
: all_non_exited_process_targets ())
4912 switch_to_target_no_thread (target
);
4913 target_thread_events (false);
4916 /* Use debug_prefixed_printf directly to get a meaningful function
4919 debug_prefixed_printf ("infrun", "stop_all_threads", "done");
4922 /* Request threads to stop, and then wait for the stops. Because
4923 threads we already know about can spawn more threads while we're
4924 trying to stop them, and we only learn about new threads when we
4925 update the thread list, do this in a loop, and keep iterating
4926 until two passes find no threads that need to be stopped. */
4927 for (pass
= 0; pass
< 2; pass
++, iterations
++)
4929 infrun_debug_printf ("pass=%d, iterations=%d", pass
, iterations
);
4932 int waits_needed
= 0;
4934 for (auto *target
: all_non_exited_process_targets ())
4936 switch_to_target_no_thread (target
);
4937 update_thread_list ();
4940 /* Go through all threads looking for threads that we need
4941 to tell the target to stop. */
4942 for (thread_info
*t
: all_non_exited_threads ())
4944 /* For a single-target setting with an all-stop target,
4945 we would not even arrive here. For a multi-target
4946 setting, until GDB is able to handle a mixture of
4947 all-stop and non-stop targets, simply skip all-stop
4948 targets' threads. This should be fine due to the
4949 protection of 'check_multi_target_resumption'. */
4951 switch_to_thread_no_regs (t
);
4952 if (!target_is_non_stop_p ())
4957 /* If already stopping, don't request a stop again.
4958 We just haven't seen the notification yet. */
4959 if (!t
->stop_requested
)
4961 infrun_debug_printf (" %s executing, need stop",
4962 target_pid_to_str (t
->ptid
).c_str ());
4963 target_stop (t
->ptid
);
4964 t
->stop_requested
= 1;
4968 infrun_debug_printf (" %s executing, already stopping",
4969 target_pid_to_str (t
->ptid
).c_str ());
4972 if (t
->stop_requested
)
4977 infrun_debug_printf (" %s not executing",
4978 target_pid_to_str (t
->ptid
).c_str ());
4980 /* The thread may be not executing, but still be
4981 resumed with a pending status to process. */
4982 t
->set_resumed (false);
4986 if (waits_needed
== 0)
4989 /* If we find new threads on the second iteration, restart
4990 over. We want to see two iterations in a row with all
4995 for (int i
= 0; i
< waits_needed
; i
++)
4997 wait_one_event event
= wait_one ();
4998 if (handle_one (event
))
5005 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
5008 handle_no_resumed (struct execution_control_state
*ecs
)
5010 if (target_can_async_p ())
5012 bool any_sync
= false;
5014 for (ui
*ui
: all_uis ())
5016 if (ui
->prompt_state
== PROMPT_BLOCKED
)
5024 /* There were no unwaited-for children left in the target, but,
5025 we're not synchronously waiting for events either. Just
5028 infrun_debug_printf ("TARGET_WAITKIND_NO_RESUMED (ignoring: bg)");
5029 prepare_to_wait (ecs
);
5034 /* Otherwise, if we were running a synchronous execution command, we
5035 may need to cancel it and give the user back the terminal.
5037 In non-stop mode, the target can't tell whether we've already
5038 consumed previous stop events, so it can end up sending us a
5039 no-resumed event like so:
5041 #0 - thread 1 is left stopped
5043 #1 - thread 2 is resumed and hits breakpoint
5044 -> TARGET_WAITKIND_STOPPED
5046 #2 - thread 3 is resumed and exits
5047 this is the last resumed thread, so
5048 -> TARGET_WAITKIND_NO_RESUMED
5050 #3 - gdb processes stop for thread 2 and decides to re-resume
5053 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
5054 thread 2 is now resumed, so the event should be ignored.
5056 IOW, if the stop for thread 2 doesn't end a foreground command,
5057 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
5058 event. But it could be that the event meant that thread 2 itself
5059 (or whatever other thread was the last resumed thread) exited.
5061 To address this we refresh the thread list and check whether we
5062 have resumed threads _now_. In the example above, this removes
5063 thread 3 from the thread list. If thread 2 was re-resumed, we
5064 ignore this event. If we find no thread resumed, then we cancel
5065 the synchronous command and show "no unwaited-for " to the
5068 inferior
*curr_inf
= current_inferior ();
5070 scoped_restore_current_thread restore_thread
;
5072 for (auto *target
: all_non_exited_process_targets ())
5074 switch_to_target_no_thread (target
);
5075 update_thread_list ();
5080 - the current target has no thread executing, and
5081 - the current inferior is native, and
5082 - the current inferior is the one which has the terminal, and
5085 then a Ctrl-C from this point on would remain stuck in the
5086 kernel, until a thread resumes and dequeues it. That would
5087 result in the GDB CLI not reacting to Ctrl-C, not able to
5088 interrupt the program. To address this, if the current inferior
5089 no longer has any thread executing, we give the terminal to some
5090 other inferior that has at least one thread executing. */
5091 bool swap_terminal
= true;
5093 /* Whether to ignore this TARGET_WAITKIND_NO_RESUMED event, or
5094 whether to report it to the user. */
5095 bool ignore_event
= false;
5097 for (thread_info
*thread
: all_non_exited_threads ())
5099 if (swap_terminal
&& thread
->executing
)
5101 if (thread
->inf
!= curr_inf
)
5103 target_terminal::ours ();
5105 switch_to_thread (thread
);
5106 target_terminal::inferior ();
5108 swap_terminal
= false;
5112 && (thread
->executing
|| thread
->has_pending_waitstatus ()))
5114 /* Either there were no unwaited-for children left in the
5115 target at some point, but there are now, or some target
5116 other than the eventing one has unwaited-for children
5117 left. Just ignore. */
5118 infrun_debug_printf ("TARGET_WAITKIND_NO_RESUMED "
5119 "(ignoring: found resumed)");
5121 ignore_event
= true;
5124 if (ignore_event
&& !swap_terminal
)
5130 switch_to_inferior_no_thread (curr_inf
);
5131 prepare_to_wait (ecs
);
5135 /* Go ahead and report the event. */
5139 /* Given an execution control state that has been freshly filled in by
5140 an event from the inferior, figure out what it means and take
5143 The alternatives are:
5145 1) stop_waiting and return; to really stop and return to the
5148 2) keep_going and return; to wait for the next event (set
5149 ecs->event_thread->stepping_over_breakpoint to 1 to single step
5153 handle_inferior_event (struct execution_control_state
*ecs
)
5155 /* Make sure that all temporary struct value objects that were
5156 created during the handling of the event get deleted at the
5158 scoped_value_mark free_values
;
5160 infrun_debug_printf ("%s", target_waitstatus_to_string (&ecs
->ws
).c_str ());
5162 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
5164 /* We had an event in the inferior, but we are not interested in
5165 handling it at this level. The lower layers have already
5166 done what needs to be done, if anything.
5168 One of the possible circumstances for this is when the
5169 inferior produces output for the console. The inferior has
5170 not stopped, and we are ignoring the event. Another possible
5171 circumstance is any event which the lower level knows will be
5172 reported multiple times without an intervening resume. */
5173 prepare_to_wait (ecs
);
5177 if (ecs
->ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
)
5179 prepare_to_wait (ecs
);
5183 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
5184 && handle_no_resumed (ecs
))
5187 /* Cache the last target/ptid/waitstatus. */
5188 set_last_target_status (ecs
->target
, ecs
->ptid
, ecs
->ws
);
5190 /* Always clear state belonging to the previous time we stopped. */
5191 stop_stack_dummy
= STOP_NONE
;
5193 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
5195 /* No unwaited-for children left. IOW, all resumed children
5197 stop_print_frame
= false;
5202 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
5203 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
5205 ecs
->event_thread
= find_thread_ptid (ecs
->target
, ecs
->ptid
);
5206 /* If it's a new thread, add it to the thread database. */
5207 if (ecs
->event_thread
== NULL
)
5208 ecs
->event_thread
= add_thread (ecs
->target
, ecs
->ptid
);
5210 /* Disable range stepping. If the next step request could use a
5211 range, this will be end up re-enabled then. */
5212 ecs
->event_thread
->control
.may_range_step
= 0;
5215 /* Dependent on valid ECS->EVENT_THREAD. */
5216 adjust_pc_after_break (ecs
->event_thread
, &ecs
->ws
);
5218 /* Dependent on the current PC value modified by adjust_pc_after_break. */
5219 reinit_frame_cache ();
5221 breakpoint_retire_moribund ();
5223 /* First, distinguish signals caused by the debugger from signals
5224 that have to do with the program's own actions. Note that
5225 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
5226 on the operating system version. Here we detect when a SIGILL or
5227 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
5228 something similar for SIGSEGV, since a SIGSEGV will be generated
5229 when we're trying to execute a breakpoint instruction on a
5230 non-executable stack. This happens for call dummy breakpoints
5231 for architectures like SPARC that place call dummies on the
5233 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
5234 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
5235 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
5236 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
5238 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
5240 if (breakpoint_inserted_here_p (regcache
->aspace (),
5241 regcache_read_pc (regcache
)))
5243 infrun_debug_printf ("Treating signal as SIGTRAP");
5244 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
5248 mark_non_executing_threads (ecs
->target
, ecs
->ptid
, ecs
->ws
);
5250 switch (ecs
->ws
.kind
)
5252 case TARGET_WAITKIND_LOADED
:
5254 context_switch (ecs
);
5255 /* Ignore gracefully during startup of the inferior, as it might
5256 be the shell which has just loaded some objects, otherwise
5257 add the symbols for the newly loaded objects. Also ignore at
5258 the beginning of an attach or remote session; we will query
5259 the full list of libraries once the connection is
5262 stop_kind stop_soon
= get_inferior_stop_soon (ecs
);
5263 if (stop_soon
== NO_STOP_QUIETLY
)
5265 struct regcache
*regcache
;
5267 regcache
= get_thread_regcache (ecs
->event_thread
);
5269 handle_solib_event ();
5271 ecs
->event_thread
->control
.stop_bpstat
5272 = bpstat_stop_status (regcache
->aspace (),
5273 ecs
->event_thread
->stop_pc (),
5274 ecs
->event_thread
, &ecs
->ws
);
5276 if (handle_stop_requested (ecs
))
5279 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5281 /* A catchpoint triggered. */
5282 process_event_stop_test (ecs
);
5286 /* If requested, stop when the dynamic linker notifies
5287 gdb of events. This allows the user to get control
5288 and place breakpoints in initializer routines for
5289 dynamically loaded objects (among other things). */
5290 ecs
->event_thread
->set_stop_signal (GDB_SIGNAL_0
);
5291 if (stop_on_solib_events
)
5293 /* Make sure we print "Stopped due to solib-event" in
5295 stop_print_frame
= true;
5302 /* If we are skipping through a shell, or through shared library
5303 loading that we aren't interested in, resume the program. If
5304 we're running the program normally, also resume. */
5305 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
5307 /* Loading of shared libraries might have changed breakpoint
5308 addresses. Make sure new breakpoints are inserted. */
5309 if (stop_soon
== NO_STOP_QUIETLY
)
5310 insert_breakpoints ();
5311 resume (GDB_SIGNAL_0
);
5312 prepare_to_wait (ecs
);
5316 /* But stop if we're attaching or setting up a remote
5318 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5319 || stop_soon
== STOP_QUIETLY_REMOTE
)
5321 infrun_debug_printf ("quietly stopped");
5326 internal_error (__FILE__
, __LINE__
,
5327 _("unhandled stop_soon: %d"), (int) stop_soon
);
5330 case TARGET_WAITKIND_SPURIOUS
:
5331 if (handle_stop_requested (ecs
))
5333 context_switch (ecs
);
5334 resume (GDB_SIGNAL_0
);
5335 prepare_to_wait (ecs
);
5338 case TARGET_WAITKIND_THREAD_CREATED
:
5339 if (handle_stop_requested (ecs
))
5341 context_switch (ecs
);
5342 if (!switch_back_to_stepped_thread (ecs
))
5346 case TARGET_WAITKIND_EXITED
:
5347 case TARGET_WAITKIND_SIGNALLED
:
5349 /* Depending on the system, ecs->ptid may point to a thread or
5350 to a process. On some targets, target_mourn_inferior may
5351 need to have access to the just-exited thread. That is the
5352 case of GNU/Linux's "checkpoint" support, for example.
5353 Call the switch_to_xxx routine as appropriate. */
5354 thread_info
*thr
= find_thread_ptid (ecs
->target
, ecs
->ptid
);
5356 switch_to_thread (thr
);
5359 inferior
*inf
= find_inferior_ptid (ecs
->target
, ecs
->ptid
);
5360 switch_to_inferior_no_thread (inf
);
5363 handle_vfork_child_exec_or_exit (0);
5364 target_terminal::ours (); /* Must do this before mourn anyway. */
5366 /* Clearing any previous state of convenience variables. */
5367 clear_exit_convenience_vars ();
5369 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5371 /* Record the exit code in the convenience variable $_exitcode, so
5372 that the user can inspect this again later. */
5373 set_internalvar_integer (lookup_internalvar ("_exitcode"),
5374 (LONGEST
) ecs
->ws
.value
.integer
);
5376 /* Also record this in the inferior itself. */
5377 current_inferior ()->has_exit_code
= 1;
5378 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
5380 /* Support the --return-child-result option. */
5381 return_child_result_value
= ecs
->ws
.value
.integer
;
5383 gdb::observers::exited
.notify (ecs
->ws
.value
.integer
);
5387 struct gdbarch
*gdbarch
= current_inferior ()->gdbarch
;
5389 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
5391 /* Set the value of the internal variable $_exitsignal,
5392 which holds the signal uncaught by the inferior. */
5393 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
5394 gdbarch_gdb_signal_to_target (gdbarch
,
5395 ecs
->ws
.value
.sig
));
5399 /* We don't have access to the target's method used for
5400 converting between signal numbers (GDB's internal
5401 representation <-> target's representation).
5402 Therefore, we cannot do a good job at displaying this
5403 information to the user. It's better to just warn
5404 her about it (if infrun debugging is enabled), and
5406 infrun_debug_printf ("Cannot fill $_exitsignal with the correct "
5410 gdb::observers::signal_exited
.notify (ecs
->ws
.value
.sig
);
5413 gdb_flush (gdb_stdout
);
5414 target_mourn_inferior (inferior_ptid
);
5415 stop_print_frame
= false;
5419 case TARGET_WAITKIND_FORKED
:
5420 case TARGET_WAITKIND_VFORKED
:
5421 /* Check whether the inferior is displaced stepping. */
5423 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
5424 struct gdbarch
*gdbarch
= regcache
->arch ();
5425 inferior
*parent_inf
= find_inferior_ptid (ecs
->target
, ecs
->ptid
);
5427 /* If this is a fork (child gets its own address space copy)
5428 and some displaced step buffers were in use at the time of
5429 the fork, restore the displaced step buffer bytes in the
5432 Architectures which support displaced stepping and fork
5433 events must supply an implementation of
5434 gdbarch_displaced_step_restore_all_in_ptid. This is not
5435 enforced during gdbarch validation to support architectures
5436 which support displaced stepping but not forks. */
5437 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
5438 && gdbarch_supports_displaced_stepping (gdbarch
))
5439 gdbarch_displaced_step_restore_all_in_ptid
5440 (gdbarch
, parent_inf
, ecs
->ws
.value
.related_pid
);
5442 /* If displaced stepping is supported, and thread ecs->ptid is
5443 displaced stepping. */
5444 if (displaced_step_in_progress_thread (ecs
->event_thread
))
5446 struct regcache
*child_regcache
;
5447 CORE_ADDR parent_pc
;
5449 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
5450 indicating that the displaced stepping of syscall instruction
5451 has been done. Perform cleanup for parent process here. Note
5452 that this operation also cleans up the child process for vfork,
5453 because their pages are shared. */
5454 displaced_step_finish (ecs
->event_thread
, GDB_SIGNAL_TRAP
);
5455 /* Start a new step-over in another thread if there's one
5459 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
5460 the child's PC is also within the scratchpad. Set the child's PC
5461 to the parent's PC value, which has already been fixed up.
5462 FIXME: we use the parent's aspace here, although we're touching
5463 the child, because the child hasn't been added to the inferior
5464 list yet at this point. */
5467 = get_thread_arch_aspace_regcache (parent_inf
->process_target (),
5468 ecs
->ws
.value
.related_pid
,
5470 parent_inf
->aspace
);
5471 /* Read PC value of parent process. */
5472 parent_pc
= regcache_read_pc (regcache
);
5474 displaced_debug_printf ("write child pc from %s to %s",
5476 regcache_read_pc (child_regcache
)),
5477 paddress (gdbarch
, parent_pc
));
5479 regcache_write_pc (child_regcache
, parent_pc
);
5483 context_switch (ecs
);
5485 /* Immediately detach breakpoints from the child before there's
5486 any chance of letting the user delete breakpoints from the
5487 breakpoint lists. If we don't do this early, it's easy to
5488 leave left over traps in the child, vis: "break foo; catch
5489 fork; c; <fork>; del; c; <child calls foo>". We only follow
5490 the fork on the last `continue', and by that time the
5491 breakpoint at "foo" is long gone from the breakpoint table.
5492 If we vforked, then we don't need to unpatch here, since both
5493 parent and child are sharing the same memory pages; we'll
5494 need to unpatch at follow/detach time instead to be certain
5495 that new breakpoints added between catchpoint hit time and
5496 vfork follow are detached. */
5497 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
5499 /* This won't actually modify the breakpoint list, but will
5500 physically remove the breakpoints from the child. */
5501 detach_breakpoints (ecs
->ws
.value
.related_pid
);
5504 delete_just_stopped_threads_single_step_breakpoints ();
5506 /* In case the event is caught by a catchpoint, remember that
5507 the event is to be followed at the next resume of the thread,
5508 and not immediately. */
5509 ecs
->event_thread
->pending_follow
= ecs
->ws
;
5511 ecs
->event_thread
->set_stop_pc
5512 (regcache_read_pc (get_thread_regcache (ecs
->event_thread
)));
5514 ecs
->event_thread
->control
.stop_bpstat
5515 = bpstat_stop_status (get_current_regcache ()->aspace (),
5516 ecs
->event_thread
->stop_pc (),
5517 ecs
->event_thread
, &ecs
->ws
);
5519 if (handle_stop_requested (ecs
))
5522 /* If no catchpoint triggered for this, then keep going. Note
5523 that we're interested in knowing the bpstat actually causes a
5524 stop, not just if it may explain the signal. Software
5525 watchpoints, for example, always appear in the bpstat. */
5526 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5529 = (follow_fork_mode_string
== follow_fork_mode_child
);
5531 ecs
->event_thread
->set_stop_signal (GDB_SIGNAL_0
);
5533 process_stratum_target
*targ
5534 = ecs
->event_thread
->inf
->process_target ();
5536 bool should_resume
= follow_fork ();
5538 /* Note that one of these may be an invalid pointer,
5539 depending on detach_fork. */
5540 thread_info
*parent
= ecs
->event_thread
;
5542 = find_thread_ptid (targ
, ecs
->ws
.value
.related_pid
);
5544 /* At this point, the parent is marked running, and the
5545 child is marked stopped. */
5547 /* If not resuming the parent, mark it stopped. */
5548 if (follow_child
&& !detach_fork
&& !non_stop
&& !sched_multi
)
5549 parent
->set_running (false);
5551 /* If resuming the child, mark it running. */
5552 if (follow_child
|| (!detach_fork
&& (non_stop
|| sched_multi
)))
5553 child
->set_running (true);
5555 /* In non-stop mode, also resume the other branch. */
5556 if (!detach_fork
&& (non_stop
5557 || (sched_multi
&& target_is_non_stop_p ())))
5560 switch_to_thread (parent
);
5562 switch_to_thread (child
);
5564 ecs
->event_thread
= inferior_thread ();
5565 ecs
->ptid
= inferior_ptid
;
5570 switch_to_thread (child
);
5572 switch_to_thread (parent
);
5574 ecs
->event_thread
= inferior_thread ();
5575 ecs
->ptid
= inferior_ptid
;
5583 process_event_stop_test (ecs
);
5586 case TARGET_WAITKIND_VFORK_DONE
:
5587 /* Done with the shared memory region. Re-insert breakpoints in
5588 the parent, and keep going. */
5590 context_switch (ecs
);
5592 current_inferior ()->waiting_for_vfork_done
= 0;
5593 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
5595 if (handle_stop_requested (ecs
))
5598 /* This also takes care of reinserting breakpoints in the
5599 previously locked inferior. */
5603 case TARGET_WAITKIND_EXECD
:
5605 /* Note we can't read registers yet (the stop_pc), because we
5606 don't yet know the inferior's post-exec architecture.
5607 'stop_pc' is explicitly read below instead. */
5608 switch_to_thread_no_regs (ecs
->event_thread
);
5610 /* Do whatever is necessary to the parent branch of the vfork. */
5611 handle_vfork_child_exec_or_exit (1);
5613 /* This causes the eventpoints and symbol table to be reset.
5614 Must do this now, before trying to determine whether to
5616 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
5618 /* In follow_exec we may have deleted the original thread and
5619 created a new one. Make sure that the event thread is the
5620 execd thread for that case (this is a nop otherwise). */
5621 ecs
->event_thread
= inferior_thread ();
5623 ecs
->event_thread
->set_stop_pc
5624 (regcache_read_pc (get_thread_regcache (ecs
->event_thread
)));
5626 ecs
->event_thread
->control
.stop_bpstat
5627 = bpstat_stop_status (get_current_regcache ()->aspace (),
5628 ecs
->event_thread
->stop_pc (),
5629 ecs
->event_thread
, &ecs
->ws
);
5631 /* Note that this may be referenced from inside
5632 bpstat_stop_status above, through inferior_has_execd. */
5633 xfree (ecs
->ws
.value
.execd_pathname
);
5634 ecs
->ws
.value
.execd_pathname
= NULL
;
5636 if (handle_stop_requested (ecs
))
5639 /* If no catchpoint triggered for this, then keep going. */
5640 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5642 ecs
->event_thread
->set_stop_signal (GDB_SIGNAL_0
);
5646 process_event_stop_test (ecs
);
5649 /* Be careful not to try to gather much state about a thread
5650 that's in a syscall. It's frequently a losing proposition. */
5651 case TARGET_WAITKIND_SYSCALL_ENTRY
:
5652 /* Getting the current syscall number. */
5653 if (handle_syscall_event (ecs
) == 0)
5654 process_event_stop_test (ecs
);
5657 /* Before examining the threads further, step this thread to
5658 get it entirely out of the syscall. (We get notice of the
5659 event when the thread is just on the verge of exiting a
5660 syscall. Stepping one instruction seems to get it back
5662 case TARGET_WAITKIND_SYSCALL_RETURN
:
5663 if (handle_syscall_event (ecs
) == 0)
5664 process_event_stop_test (ecs
);
5667 case TARGET_WAITKIND_STOPPED
:
5668 handle_signal_stop (ecs
);
5671 case TARGET_WAITKIND_NO_HISTORY
:
5672 /* Reverse execution: target ran out of history info. */
5674 /* Switch to the stopped thread. */
5675 context_switch (ecs
);
5676 infrun_debug_printf ("stopped");
5678 delete_just_stopped_threads_single_step_breakpoints ();
5679 ecs
->event_thread
->set_stop_pc
5680 (regcache_read_pc (get_thread_regcache (inferior_thread ())));
5682 if (handle_stop_requested (ecs
))
5685 gdb::observers::no_history
.notify ();
5691 /* Restart threads back to what they were trying to do back when we
5692 paused them for an in-line step-over. The EVENT_THREAD thread is
5696 restart_threads (struct thread_info
*event_thread
)
5698 /* In case the instruction just stepped spawned a new thread. */
5699 update_thread_list ();
5701 for (thread_info
*tp
: all_non_exited_threads ())
5703 if (tp
->inf
->detaching
)
5705 infrun_debug_printf ("restart threads: [%s] inferior detaching",
5706 target_pid_to_str (tp
->ptid
).c_str ());
5710 switch_to_thread_no_regs (tp
);
5712 if (tp
== event_thread
)
5714 infrun_debug_printf ("restart threads: [%s] is event thread",
5715 target_pid_to_str (tp
->ptid
).c_str ());
5719 if (!(tp
->state
== THREAD_RUNNING
|| tp
->control
.in_infcall
))
5721 infrun_debug_printf ("restart threads: [%s] not meant to be running",
5722 target_pid_to_str (tp
->ptid
).c_str ());
5728 infrun_debug_printf ("restart threads: [%s] resumed",
5729 target_pid_to_str (tp
->ptid
).c_str ());
5730 gdb_assert (tp
->executing
|| tp
->has_pending_waitstatus ());
5734 if (thread_is_in_step_over_chain (tp
))
5736 infrun_debug_printf ("restart threads: [%s] needs step-over",
5737 target_pid_to_str (tp
->ptid
).c_str ());
5738 gdb_assert (!tp
->resumed ());
5743 if (tp
->has_pending_waitstatus ())
5745 infrun_debug_printf ("restart threads: [%s] has pending status",
5746 target_pid_to_str (tp
->ptid
).c_str ());
5747 tp
->set_resumed (true);
5751 gdb_assert (!tp
->stop_requested
);
5753 /* If some thread needs to start a step-over at this point, it
5754 should still be in the step-over queue, and thus skipped
5756 if (thread_still_needs_step_over (tp
))
5758 internal_error (__FILE__
, __LINE__
,
5759 "thread [%s] needs a step-over, but not in "
5760 "step-over queue\n",
5761 target_pid_to_str (tp
->ptid
).c_str ());
5764 if (currently_stepping (tp
))
5766 infrun_debug_printf ("restart threads: [%s] was stepping",
5767 target_pid_to_str (tp
->ptid
).c_str ());
5768 keep_going_stepped_thread (tp
);
5772 struct execution_control_state ecss
;
5773 struct execution_control_state
*ecs
= &ecss
;
5775 infrun_debug_printf ("restart threads: [%s] continuing",
5776 target_pid_to_str (tp
->ptid
).c_str ());
5777 reset_ecs (ecs
, tp
);
5778 switch_to_thread (tp
);
5779 keep_going_pass_signal (ecs
);
5784 /* Callback for iterate_over_threads. Find a resumed thread that has
5785 a pending waitstatus. */
5788 resumed_thread_with_pending_status (struct thread_info
*tp
,
5791 return tp
->resumed () && tp
->has_pending_waitstatus ();
5794 /* Called when we get an event that may finish an in-line or
5795 out-of-line (displaced stepping) step-over started previously.
5796 Return true if the event is processed and we should go back to the
5797 event loop; false if the caller should continue processing the
5801 finish_step_over (struct execution_control_state
*ecs
)
5803 displaced_step_finish (ecs
->event_thread
, ecs
->event_thread
->stop_signal ());
5805 bool had_step_over_info
= step_over_info_valid_p ();
5807 if (had_step_over_info
)
5809 /* If we're stepping over a breakpoint with all threads locked,
5810 then only the thread that was stepped should be reporting
5812 gdb_assert (ecs
->event_thread
->control
.trap_expected
);
5814 clear_step_over_info ();
5817 if (!target_is_non_stop_p ())
5820 /* Start a new step-over in another thread if there's one that
5824 /* If we were stepping over a breakpoint before, and haven't started
5825 a new in-line step-over sequence, then restart all other threads
5826 (except the event thread). We can't do this in all-stop, as then
5827 e.g., we wouldn't be able to issue any other remote packet until
5828 these other threads stop. */
5829 if (had_step_over_info
&& !step_over_info_valid_p ())
5831 struct thread_info
*pending
;
5833 /* If we only have threads with pending statuses, the restart
5834 below won't restart any thread and so nothing re-inserts the
5835 breakpoint we just stepped over. But we need it inserted
5836 when we later process the pending events, otherwise if
5837 another thread has a pending event for this breakpoint too,
5838 we'd discard its event (because the breakpoint that
5839 originally caused the event was no longer inserted). */
5840 context_switch (ecs
);
5841 insert_breakpoints ();
5843 restart_threads (ecs
->event_thread
);
5845 /* If we have events pending, go through handle_inferior_event
5846 again, picking up a pending event at random. This avoids
5847 thread starvation. */
5849 /* But not if we just stepped over a watchpoint in order to let
5850 the instruction execute so we can evaluate its expression.
5851 The set of watchpoints that triggered is recorded in the
5852 breakpoint objects themselves (see bp->watchpoint_triggered).
5853 If we processed another event first, that other event could
5854 clobber this info. */
5855 if (ecs
->event_thread
->stepping_over_watchpoint
)
5858 pending
= iterate_over_threads (resumed_thread_with_pending_status
,
5860 if (pending
!= NULL
)
5862 struct thread_info
*tp
= ecs
->event_thread
;
5863 struct regcache
*regcache
;
5865 infrun_debug_printf ("found resumed threads with "
5866 "pending events, saving status");
5868 gdb_assert (pending
!= tp
);
5870 /* Record the event thread's event for later. */
5871 save_waitstatus (tp
, &ecs
->ws
);
5872 /* This was cleared early, by handle_inferior_event. Set it
5873 so this pending event is considered by
5875 tp
->set_resumed (true);
5877 gdb_assert (!tp
->executing
);
5879 regcache
= get_thread_regcache (tp
);
5880 tp
->set_stop_pc (regcache_read_pc (regcache
));
5882 infrun_debug_printf ("saved stop_pc=%s for %s "
5883 "(currently_stepping=%d)",
5884 paddress (target_gdbarch (), tp
->stop_pc ()),
5885 target_pid_to_str (tp
->ptid
).c_str (),
5886 currently_stepping (tp
));
5888 /* This in-line step-over finished; clear this so we won't
5889 start a new one. This is what handle_signal_stop would
5890 do, if we returned false. */
5891 tp
->stepping_over_breakpoint
= 0;
5893 /* Wake up the event loop again. */
5894 mark_async_event_handler (infrun_async_inferior_event_token
);
5896 prepare_to_wait (ecs
);
5904 /* Come here when the program has stopped with a signal. */
5907 handle_signal_stop (struct execution_control_state
*ecs
)
5909 struct frame_info
*frame
;
5910 struct gdbarch
*gdbarch
;
5911 int stopped_by_watchpoint
;
5912 enum stop_kind stop_soon
;
5915 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
5917 ecs
->event_thread
->set_stop_signal (ecs
->ws
.value
.sig
);
5919 /* Do we need to clean up the state of a thread that has
5920 completed a displaced single-step? (Doing so usually affects
5921 the PC, so do it here, before we set stop_pc.) */
5922 if (finish_step_over (ecs
))
5925 /* If we either finished a single-step or hit a breakpoint, but
5926 the user wanted this thread to be stopped, pretend we got a
5927 SIG0 (generic unsignaled stop). */
5928 if (ecs
->event_thread
->stop_requested
5929 && ecs
->event_thread
->stop_signal () == GDB_SIGNAL_TRAP
)
5930 ecs
->event_thread
->set_stop_signal (GDB_SIGNAL_0
);
5932 ecs
->event_thread
->set_stop_pc
5933 (regcache_read_pc (get_thread_regcache (ecs
->event_thread
)));
5935 context_switch (ecs
);
5937 if (deprecated_context_hook
)
5938 deprecated_context_hook (ecs
->event_thread
->global_num
);
5942 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
5943 struct gdbarch
*reg_gdbarch
= regcache
->arch ();
5946 ("stop_pc=%s", paddress (reg_gdbarch
, ecs
->event_thread
->stop_pc ()));
5947 if (target_stopped_by_watchpoint ())
5951 infrun_debug_printf ("stopped by watchpoint");
5953 if (target_stopped_data_address (current_inferior ()->top_target (),
5955 infrun_debug_printf ("stopped data address=%s",
5956 paddress (reg_gdbarch
, addr
));
5958 infrun_debug_printf ("(no data address available)");
5962 /* This is originated from start_remote(), start_inferior() and
5963 shared libraries hook functions. */
5964 stop_soon
= get_inferior_stop_soon (ecs
);
5965 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
5967 infrun_debug_printf ("quietly stopped");
5968 stop_print_frame
= true;
5973 /* This originates from attach_command(). We need to overwrite
5974 the stop_signal here, because some kernels don't ignore a
5975 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5976 See more comments in inferior.h. On the other hand, if we
5977 get a non-SIGSTOP, report it to the user - assume the backend
5978 will handle the SIGSTOP if it should show up later.
5980 Also consider that the attach is complete when we see a
5981 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5982 target extended-remote report it instead of a SIGSTOP
5983 (e.g. gdbserver). We already rely on SIGTRAP being our
5984 signal, so this is no exception.
5986 Also consider that the attach is complete when we see a
5987 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5988 the target to stop all threads of the inferior, in case the
5989 low level attach operation doesn't stop them implicitly. If
5990 they weren't stopped implicitly, then the stub will report a
5991 GDB_SIGNAL_0, meaning: stopped for no particular reason
5992 other than GDB's request. */
5993 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5994 && (ecs
->event_thread
->stop_signal () == GDB_SIGNAL_STOP
5995 || ecs
->event_thread
->stop_signal () == GDB_SIGNAL_TRAP
5996 || ecs
->event_thread
->stop_signal () == GDB_SIGNAL_0
))
5998 stop_print_frame
= true;
6000 ecs
->event_thread
->set_stop_signal (GDB_SIGNAL_0
);
6004 /* At this point, get hold of the now-current thread's frame. */
6005 frame
= get_current_frame ();
6006 gdbarch
= get_frame_arch (frame
);
6008 /* Pull the single step breakpoints out of the target. */
6009 if (ecs
->event_thread
->stop_signal () == GDB_SIGNAL_TRAP
)
6011 struct regcache
*regcache
;
6014 regcache
= get_thread_regcache (ecs
->event_thread
);
6015 const address_space
*aspace
= regcache
->aspace ();
6017 pc
= regcache_read_pc (regcache
);
6019 /* However, before doing so, if this single-step breakpoint was
6020 actually for another thread, set this thread up for moving
6022 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
6025 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
6027 infrun_debug_printf ("[%s] hit another thread's single-step "
6029 target_pid_to_str (ecs
->ptid
).c_str ());
6030 ecs
->hit_singlestep_breakpoint
= 1;
6035 infrun_debug_printf ("[%s] hit its single-step breakpoint",
6036 target_pid_to_str (ecs
->ptid
).c_str ());
6039 delete_just_stopped_threads_single_step_breakpoints ();
6041 if (ecs
->event_thread
->stop_signal () == GDB_SIGNAL_TRAP
6042 && ecs
->event_thread
->control
.trap_expected
6043 && ecs
->event_thread
->stepping_over_watchpoint
)
6044 stopped_by_watchpoint
= 0;
6046 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
6048 /* If necessary, step over this watchpoint. We'll be back to display
6050 if (stopped_by_watchpoint
6051 && (target_have_steppable_watchpoint ()
6052 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
6054 /* At this point, we are stopped at an instruction which has
6055 attempted to write to a piece of memory under control of
6056 a watchpoint. The instruction hasn't actually executed
6057 yet. If we were to evaluate the watchpoint expression
6058 now, we would get the old value, and therefore no change
6059 would seem to have occurred.
6061 In order to make watchpoints work `right', we really need
6062 to complete the memory write, and then evaluate the
6063 watchpoint expression. We do this by single-stepping the
6066 It may not be necessary to disable the watchpoint to step over
6067 it. For example, the PA can (with some kernel cooperation)
6068 single step over a watchpoint without disabling the watchpoint.
6070 It is far more common to need to disable a watchpoint to step
6071 the inferior over it. If we have non-steppable watchpoints,
6072 we must disable the current watchpoint; it's simplest to
6073 disable all watchpoints.
6075 Any breakpoint at PC must also be stepped over -- if there's
6076 one, it will have already triggered before the watchpoint
6077 triggered, and we either already reported it to the user, or
6078 it didn't cause a stop and we called keep_going. In either
6079 case, if there was a breakpoint at PC, we must be trying to
6081 ecs
->event_thread
->stepping_over_watchpoint
= 1;
6086 ecs
->event_thread
->stepping_over_breakpoint
= 0;
6087 ecs
->event_thread
->stepping_over_watchpoint
= 0;
6088 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
6089 ecs
->event_thread
->control
.stop_step
= 0;
6090 stop_print_frame
= true;
6091 stopped_by_random_signal
= 0;
6092 bpstat stop_chain
= NULL
;
6094 /* Hide inlined functions starting here, unless we just performed stepi or
6095 nexti. After stepi and nexti, always show the innermost frame (not any
6096 inline function call sites). */
6097 if (ecs
->event_thread
->control
.step_range_end
!= 1)
6099 const address_space
*aspace
6100 = get_thread_regcache (ecs
->event_thread
)->aspace ();
6102 /* skip_inline_frames is expensive, so we avoid it if we can
6103 determine that the address is one where functions cannot have
6104 been inlined. This improves performance with inferiors that
6105 load a lot of shared libraries, because the solib event
6106 breakpoint is defined as the address of a function (i.e. not
6107 inline). Note that we have to check the previous PC as well
6108 as the current one to catch cases when we have just
6109 single-stepped off a breakpoint prior to reinstating it.
6110 Note that we're assuming that the code we single-step to is
6111 not inline, but that's not definitive: there's nothing
6112 preventing the event breakpoint function from containing
6113 inlined code, and the single-step ending up there. If the
6114 user had set a breakpoint on that inlined code, the missing
6115 skip_inline_frames call would break things. Fortunately
6116 that's an extremely unlikely scenario. */
6117 if (!pc_at_non_inline_function (aspace
,
6118 ecs
->event_thread
->stop_pc (),
6120 && !(ecs
->event_thread
->stop_signal () == GDB_SIGNAL_TRAP
6121 && ecs
->event_thread
->control
.trap_expected
6122 && pc_at_non_inline_function (aspace
,
6123 ecs
->event_thread
->prev_pc
,
6126 stop_chain
= build_bpstat_chain (aspace
,
6127 ecs
->event_thread
->stop_pc (),
6129 skip_inline_frames (ecs
->event_thread
, stop_chain
);
6131 /* Re-fetch current thread's frame in case that invalidated
6133 frame
= get_current_frame ();
6134 gdbarch
= get_frame_arch (frame
);
6138 if (ecs
->event_thread
->stop_signal () == GDB_SIGNAL_TRAP
6139 && ecs
->event_thread
->control
.trap_expected
6140 && gdbarch_single_step_through_delay_p (gdbarch
)
6141 && currently_stepping (ecs
->event_thread
))
6143 /* We're trying to step off a breakpoint. Turns out that we're
6144 also on an instruction that needs to be stepped multiple
6145 times before it's been fully executing. E.g., architectures
6146 with a delay slot. It needs to be stepped twice, once for
6147 the instruction and once for the delay slot. */
6148 int step_through_delay
6149 = gdbarch_single_step_through_delay (gdbarch
, frame
);
6151 if (step_through_delay
)
6152 infrun_debug_printf ("step through delay");
6154 if (ecs
->event_thread
->control
.step_range_end
== 0
6155 && step_through_delay
)
6157 /* The user issued a continue when stopped at a breakpoint.
6158 Set up for another trap and get out of here. */
6159 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6163 else if (step_through_delay
)
6165 /* The user issued a step when stopped at a breakpoint.
6166 Maybe we should stop, maybe we should not - the delay
6167 slot *might* correspond to a line of source. In any
6168 case, don't decide that here, just set
6169 ecs->stepping_over_breakpoint, making sure we
6170 single-step again before breakpoints are re-inserted. */
6171 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6175 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
6176 handles this event. */
6177 ecs
->event_thread
->control
.stop_bpstat
6178 = bpstat_stop_status (get_current_regcache ()->aspace (),
6179 ecs
->event_thread
->stop_pc (),
6180 ecs
->event_thread
, &ecs
->ws
, stop_chain
);
6182 /* Following in case break condition called a
6184 stop_print_frame
= true;
6186 /* This is where we handle "moribund" watchpoints. Unlike
6187 software breakpoints traps, hardware watchpoint traps are
6188 always distinguishable from random traps. If no high-level
6189 watchpoint is associated with the reported stop data address
6190 anymore, then the bpstat does not explain the signal ---
6191 simply make sure to ignore it if `stopped_by_watchpoint' is
6194 if (ecs
->event_thread
->stop_signal () == GDB_SIGNAL_TRAP
6195 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
6197 && stopped_by_watchpoint
)
6199 infrun_debug_printf ("no user watchpoint explains watchpoint SIGTRAP, "
6203 /* NOTE: cagney/2003-03-29: These checks for a random signal
6204 at one stage in the past included checks for an inferior
6205 function call's call dummy's return breakpoint. The original
6206 comment, that went with the test, read:
6208 ``End of a stack dummy. Some systems (e.g. Sony news) give
6209 another signal besides SIGTRAP, so check here as well as
6212 If someone ever tries to get call dummys on a
6213 non-executable stack to work (where the target would stop
6214 with something like a SIGSEGV), then those tests might need
6215 to be re-instated. Given, however, that the tests were only
6216 enabled when momentary breakpoints were not being used, I
6217 suspect that it won't be the case.
6219 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
6220 be necessary for call dummies on a non-executable stack on
6223 /* See if the breakpoints module can explain the signal. */
6225 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
6226 ecs
->event_thread
->stop_signal ());
6228 /* Maybe this was a trap for a software breakpoint that has since
6230 if (random_signal
&& target_stopped_by_sw_breakpoint ())
6232 if (gdbarch_program_breakpoint_here_p (gdbarch
,
6233 ecs
->event_thread
->stop_pc ()))
6235 struct regcache
*regcache
;
6238 /* Re-adjust PC to what the program would see if GDB was not
6240 regcache
= get_thread_regcache (ecs
->event_thread
);
6241 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
6244 gdb::optional
<scoped_restore_tmpl
<int>>
6245 restore_operation_disable
;
6247 if (record_full_is_used ())
6248 restore_operation_disable
.emplace
6249 (record_full_gdb_operation_disable_set ());
6251 regcache_write_pc (regcache
,
6252 ecs
->event_thread
->stop_pc () + decr_pc
);
6257 /* A delayed software breakpoint event. Ignore the trap. */
6258 infrun_debug_printf ("delayed software breakpoint trap, ignoring");
6263 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
6264 has since been removed. */
6265 if (random_signal
&& target_stopped_by_hw_breakpoint ())
6267 /* A delayed hardware breakpoint event. Ignore the trap. */
6268 infrun_debug_printf ("delayed hardware breakpoint/watchpoint "
6273 /* If not, perhaps stepping/nexting can. */
6275 random_signal
= !(ecs
->event_thread
->stop_signal () == GDB_SIGNAL_TRAP
6276 && currently_stepping (ecs
->event_thread
));
6278 /* Perhaps the thread hit a single-step breakpoint of _another_
6279 thread. Single-step breakpoints are transparent to the
6280 breakpoints module. */
6282 random_signal
= !ecs
->hit_singlestep_breakpoint
;
6284 /* No? Perhaps we got a moribund watchpoint. */
6286 random_signal
= !stopped_by_watchpoint
;
6288 /* Always stop if the user explicitly requested this thread to
6290 if (ecs
->event_thread
->stop_requested
)
6293 infrun_debug_printf ("user-requested stop");
6296 /* For the program's own signals, act according to
6297 the signal handling tables. */
6301 /* Signal not for debugging purposes. */
6302 enum gdb_signal stop_signal
= ecs
->event_thread
->stop_signal ();
6304 infrun_debug_printf ("random signal (%s)",
6305 gdb_signal_to_symbol_string (stop_signal
));
6307 stopped_by_random_signal
= 1;
6309 /* Always stop on signals if we're either just gaining control
6310 of the program, or the user explicitly requested this thread
6311 to remain stopped. */
6312 if (stop_soon
!= NO_STOP_QUIETLY
6313 || ecs
->event_thread
->stop_requested
6314 || signal_stop_state (ecs
->event_thread
->stop_signal ()))
6320 /* Notify observers the signal has "handle print" set. Note we
6321 returned early above if stopping; normal_stop handles the
6322 printing in that case. */
6323 if (signal_print
[ecs
->event_thread
->stop_signal ()])
6325 /* The signal table tells us to print about this signal. */
6326 target_terminal::ours_for_output ();
6327 gdb::observers::signal_received
.notify (ecs
->event_thread
->stop_signal ());
6328 target_terminal::inferior ();
6331 /* Clear the signal if it should not be passed. */
6332 if (signal_program
[ecs
->event_thread
->stop_signal ()] == 0)
6333 ecs
->event_thread
->set_stop_signal (GDB_SIGNAL_0
);
6335 if (ecs
->event_thread
->prev_pc
== ecs
->event_thread
->stop_pc ()
6336 && ecs
->event_thread
->control
.trap_expected
6337 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6339 /* We were just starting a new sequence, attempting to
6340 single-step off of a breakpoint and expecting a SIGTRAP.
6341 Instead this signal arrives. This signal will take us out
6342 of the stepping range so GDB needs to remember to, when
6343 the signal handler returns, resume stepping off that
6345 /* To simplify things, "continue" is forced to use the same
6346 code paths as single-step - set a breakpoint at the
6347 signal return address and then, once hit, step off that
6349 infrun_debug_printf ("signal arrived while stepping over breakpoint");
6351 insert_hp_step_resume_breakpoint_at_frame (frame
);
6352 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6353 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6354 ecs
->event_thread
->control
.trap_expected
= 0;
6356 /* If we were nexting/stepping some other thread, switch to
6357 it, so that we don't continue it, losing control. */
6358 if (!switch_back_to_stepped_thread (ecs
))
6363 if (ecs
->event_thread
->stop_signal () != GDB_SIGNAL_0
6364 && (pc_in_thread_step_range (ecs
->event_thread
->stop_pc (),
6366 || ecs
->event_thread
->control
.step_range_end
== 1)
6367 && frame_id_eq (get_stack_frame_id (frame
),
6368 ecs
->event_thread
->control
.step_stack_frame_id
)
6369 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6371 /* The inferior is about to take a signal that will take it
6372 out of the single step range. Set a breakpoint at the
6373 current PC (which is presumably where the signal handler
6374 will eventually return) and then allow the inferior to
6377 Note that this is only needed for a signal delivered
6378 while in the single-step range. Nested signals aren't a
6379 problem as they eventually all return. */
6380 infrun_debug_printf ("signal may take us out of single-step range");
6382 clear_step_over_info ();
6383 insert_hp_step_resume_breakpoint_at_frame (frame
);
6384 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6385 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6386 ecs
->event_thread
->control
.trap_expected
= 0;
6391 /* Note: step_resume_breakpoint may be non-NULL. This occurs
6392 when either there's a nested signal, or when there's a
6393 pending signal enabled just as the signal handler returns
6394 (leaving the inferior at the step-resume-breakpoint without
6395 actually executing it). Either way continue until the
6396 breakpoint is really hit. */
6398 if (!switch_back_to_stepped_thread (ecs
))
6400 infrun_debug_printf ("random signal, keep going");
6407 process_event_stop_test (ecs
);
6410 /* Come here when we've got some debug event / signal we can explain
6411 (IOW, not a random signal), and test whether it should cause a
6412 stop, or whether we should resume the inferior (transparently).
6413 E.g., could be a breakpoint whose condition evaluates false; we
6414 could be still stepping within the line; etc. */
6417 process_event_stop_test (struct execution_control_state
*ecs
)
6419 struct symtab_and_line stop_pc_sal
;
6420 struct frame_info
*frame
;
6421 struct gdbarch
*gdbarch
;
6422 CORE_ADDR jmp_buf_pc
;
6423 struct bpstat_what what
;
6425 /* Handle cases caused by hitting a breakpoint. */
6427 frame
= get_current_frame ();
6428 gdbarch
= get_frame_arch (frame
);
6430 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
6432 if (what
.call_dummy
)
6434 stop_stack_dummy
= what
.call_dummy
;
6437 /* A few breakpoint types have callbacks associated (e.g.,
6438 bp_jit_event). Run them now. */
6439 bpstat_run_callbacks (ecs
->event_thread
->control
.stop_bpstat
);
6441 /* If we hit an internal event that triggers symbol changes, the
6442 current frame will be invalidated within bpstat_what (e.g., if we
6443 hit an internal solib event). Re-fetch it. */
6444 frame
= get_current_frame ();
6445 gdbarch
= get_frame_arch (frame
);
6447 switch (what
.main_action
)
6449 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
6450 /* If we hit the breakpoint at longjmp while stepping, we
6451 install a momentary breakpoint at the target of the
6454 infrun_debug_printf ("BPSTAT_WHAT_SET_LONGJMP_RESUME");
6456 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6458 if (what
.is_longjmp
)
6460 struct value
*arg_value
;
6462 /* If we set the longjmp breakpoint via a SystemTap probe,
6463 then use it to extract the arguments. The destination PC
6464 is the third argument to the probe. */
6465 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
6468 jmp_buf_pc
= value_as_address (arg_value
);
6469 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
6471 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
6472 || !gdbarch_get_longjmp_target (gdbarch
,
6473 frame
, &jmp_buf_pc
))
6475 infrun_debug_printf ("BPSTAT_WHAT_SET_LONGJMP_RESUME "
6476 "(!gdbarch_get_longjmp_target)");
6481 /* Insert a breakpoint at resume address. */
6482 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
6485 check_exception_resume (ecs
, frame
);
6489 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
6491 struct frame_info
*init_frame
;
6493 /* There are several cases to consider.
6495 1. The initiating frame no longer exists. In this case we
6496 must stop, because the exception or longjmp has gone too
6499 2. The initiating frame exists, and is the same as the
6500 current frame. We stop, because the exception or longjmp
6503 3. The initiating frame exists and is different from the
6504 current frame. This means the exception or longjmp has
6505 been caught beneath the initiating frame, so keep going.
6507 4. longjmp breakpoint has been placed just to protect
6508 against stale dummy frames and user is not interested in
6509 stopping around longjmps. */
6511 infrun_debug_printf ("BPSTAT_WHAT_CLEAR_LONGJMP_RESUME");
6513 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
6515 delete_exception_resume_breakpoint (ecs
->event_thread
);
6517 if (what
.is_longjmp
)
6519 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
6521 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
6529 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
6533 struct frame_id current_id
6534 = get_frame_id (get_current_frame ());
6535 if (frame_id_eq (current_id
,
6536 ecs
->event_thread
->initiating_frame
))
6538 /* Case 2. Fall through. */
6548 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6550 delete_step_resume_breakpoint (ecs
->event_thread
);
6552 end_stepping_range (ecs
);
6556 case BPSTAT_WHAT_SINGLE
:
6557 infrun_debug_printf ("BPSTAT_WHAT_SINGLE");
6558 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6559 /* Still need to check other stuff, at least the case where we
6560 are stepping and step out of the right range. */
6563 case BPSTAT_WHAT_STEP_RESUME
:
6564 infrun_debug_printf ("BPSTAT_WHAT_STEP_RESUME");
6566 delete_step_resume_breakpoint (ecs
->event_thread
);
6567 if (ecs
->event_thread
->control
.proceed_to_finish
6568 && execution_direction
== EXEC_REVERSE
)
6570 struct thread_info
*tp
= ecs
->event_thread
;
6572 /* We are finishing a function in reverse, and just hit the
6573 step-resume breakpoint at the start address of the
6574 function, and we're almost there -- just need to back up
6575 by one more single-step, which should take us back to the
6577 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
6581 fill_in_stop_func (gdbarch
, ecs
);
6582 if (ecs
->event_thread
->stop_pc () == ecs
->stop_func_start
6583 && execution_direction
== EXEC_REVERSE
)
6585 /* We are stepping over a function call in reverse, and just
6586 hit the step-resume breakpoint at the start address of
6587 the function. Go back to single-stepping, which should
6588 take us back to the function call. */
6589 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6595 case BPSTAT_WHAT_STOP_NOISY
:
6596 infrun_debug_printf ("BPSTAT_WHAT_STOP_NOISY");
6597 stop_print_frame
= true;
6599 /* Assume the thread stopped for a breakpoint. We'll still check
6600 whether a/the breakpoint is there when the thread is next
6602 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6607 case BPSTAT_WHAT_STOP_SILENT
:
6608 infrun_debug_printf ("BPSTAT_WHAT_STOP_SILENT");
6609 stop_print_frame
= false;
6611 /* Assume the thread stopped for a breakpoint. We'll still check
6612 whether a/the breakpoint is there when the thread is next
6614 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6618 case BPSTAT_WHAT_HP_STEP_RESUME
:
6619 infrun_debug_printf ("BPSTAT_WHAT_HP_STEP_RESUME");
6621 delete_step_resume_breakpoint (ecs
->event_thread
);
6622 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
6624 /* Back when the step-resume breakpoint was inserted, we
6625 were trying to single-step off a breakpoint. Go back to
6627 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6628 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6634 case BPSTAT_WHAT_KEEP_CHECKING
:
6638 /* If we stepped a permanent breakpoint and we had a high priority
6639 step-resume breakpoint for the address we stepped, but we didn't
6640 hit it, then we must have stepped into the signal handler. The
6641 step-resume was only necessary to catch the case of _not_
6642 stepping into the handler, so delete it, and fall through to
6643 checking whether the step finished. */
6644 if (ecs
->event_thread
->stepped_breakpoint
)
6646 struct breakpoint
*sr_bp
6647 = ecs
->event_thread
->control
.step_resume_breakpoint
;
6650 && sr_bp
->loc
->permanent
6651 && sr_bp
->type
== bp_hp_step_resume
6652 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
6654 infrun_debug_printf ("stepped permanent breakpoint, stopped in handler");
6655 delete_step_resume_breakpoint (ecs
->event_thread
);
6656 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6660 /* We come here if we hit a breakpoint but should not stop for it.
6661 Possibly we also were stepping and should stop for that. So fall
6662 through and test for stepping. But, if not stepping, do not
6665 /* In all-stop mode, if we're currently stepping but have stopped in
6666 some other thread, we need to switch back to the stepped thread. */
6667 if (switch_back_to_stepped_thread (ecs
))
6670 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
6672 infrun_debug_printf ("step-resume breakpoint is inserted");
6674 /* Having a step-resume breakpoint overrides anything
6675 else having to do with stepping commands until
6676 that breakpoint is reached. */
6681 if (ecs
->event_thread
->control
.step_range_end
== 0)
6683 infrun_debug_printf ("no stepping, continue");
6684 /* Likewise if we aren't even stepping. */
6689 /* Re-fetch current thread's frame in case the code above caused
6690 the frame cache to be re-initialized, making our FRAME variable
6691 a dangling pointer. */
6692 frame
= get_current_frame ();
6693 gdbarch
= get_frame_arch (frame
);
6694 fill_in_stop_func (gdbarch
, ecs
);
6696 /* If stepping through a line, keep going if still within it.
6698 Note that step_range_end is the address of the first instruction
6699 beyond the step range, and NOT the address of the last instruction
6702 Note also that during reverse execution, we may be stepping
6703 through a function epilogue and therefore must detect when
6704 the current-frame changes in the middle of a line. */
6706 if (pc_in_thread_step_range (ecs
->event_thread
->stop_pc (),
6708 && (execution_direction
!= EXEC_REVERSE
6709 || frame_id_eq (get_frame_id (frame
),
6710 ecs
->event_thread
->control
.step_frame_id
)))
6713 ("stepping inside range [%s-%s]",
6714 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
6715 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
6717 /* Tentatively re-enable range stepping; `resume' disables it if
6718 necessary (e.g., if we're stepping over a breakpoint or we
6719 have software watchpoints). */
6720 ecs
->event_thread
->control
.may_range_step
= 1;
6722 /* When stepping backward, stop at beginning of line range
6723 (unless it's the function entry point, in which case
6724 keep going back to the call point). */
6725 CORE_ADDR stop_pc
= ecs
->event_thread
->stop_pc ();
6726 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
6727 && stop_pc
!= ecs
->stop_func_start
6728 && execution_direction
== EXEC_REVERSE
)
6729 end_stepping_range (ecs
);
6736 /* We stepped out of the stepping range. */
6738 /* If we are stepping at the source level and entered the runtime
6739 loader dynamic symbol resolution code...
6741 EXEC_FORWARD: we keep on single stepping until we exit the run
6742 time loader code and reach the callee's address.
6744 EXEC_REVERSE: we've already executed the callee (backward), and
6745 the runtime loader code is handled just like any other
6746 undebuggable function call. Now we need only keep stepping
6747 backward through the trampoline code, and that's handled further
6748 down, so there is nothing for us to do here. */
6750 if (execution_direction
!= EXEC_REVERSE
6751 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6752 && in_solib_dynsym_resolve_code (ecs
->event_thread
->stop_pc ()))
6754 CORE_ADDR pc_after_resolver
=
6755 gdbarch_skip_solib_resolver (gdbarch
, ecs
->event_thread
->stop_pc ());
6757 infrun_debug_printf ("stepped into dynsym resolve code");
6759 if (pc_after_resolver
)
6761 /* Set up a step-resume breakpoint at the address
6762 indicated by SKIP_SOLIB_RESOLVER. */
6763 symtab_and_line sr_sal
;
6764 sr_sal
.pc
= pc_after_resolver
;
6765 sr_sal
.pspace
= get_frame_program_space (frame
);
6767 insert_step_resume_breakpoint_at_sal (gdbarch
,
6768 sr_sal
, null_frame_id
);
6775 /* Step through an indirect branch thunk. */
6776 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6777 && gdbarch_in_indirect_branch_thunk (gdbarch
,
6778 ecs
->event_thread
->stop_pc ()))
6780 infrun_debug_printf ("stepped into indirect branch thunk");
6785 if (ecs
->event_thread
->control
.step_range_end
!= 1
6786 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6787 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6788 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
6790 infrun_debug_printf ("stepped into signal trampoline");
6791 /* The inferior, while doing a "step" or "next", has ended up in
6792 a signal trampoline (either by a signal being delivered or by
6793 the signal handler returning). Just single-step until the
6794 inferior leaves the trampoline (either by calling the handler
6800 /* If we're in the return path from a shared library trampoline,
6801 we want to proceed through the trampoline when stepping. */
6802 /* macro/2012-04-25: This needs to come before the subroutine
6803 call check below as on some targets return trampolines look
6804 like subroutine calls (MIPS16 return thunks). */
6805 if (gdbarch_in_solib_return_trampoline (gdbarch
,
6806 ecs
->event_thread
->stop_pc (),
6807 ecs
->stop_func_name
)
6808 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6810 /* Determine where this trampoline returns. */
6811 CORE_ADDR stop_pc
= ecs
->event_thread
->stop_pc ();
6812 CORE_ADDR real_stop_pc
6813 = gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6815 infrun_debug_printf ("stepped into solib return tramp");
6817 /* Only proceed through if we know where it's going. */
6820 /* And put the step-breakpoint there and go until there. */
6821 symtab_and_line sr_sal
;
6822 sr_sal
.pc
= real_stop_pc
;
6823 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6824 sr_sal
.pspace
= get_frame_program_space (frame
);
6826 /* Do not specify what the fp should be when we stop since
6827 on some machines the prologue is where the new fp value
6829 insert_step_resume_breakpoint_at_sal (gdbarch
,
6830 sr_sal
, null_frame_id
);
6832 /* Restart without fiddling with the step ranges or
6839 /* Check for subroutine calls. The check for the current frame
6840 equalling the step ID is not necessary - the check of the
6841 previous frame's ID is sufficient - but it is a common case and
6842 cheaper than checking the previous frame's ID.
6844 NOTE: frame_id_eq will never report two invalid frame IDs as
6845 being equal, so to get into this block, both the current and
6846 previous frame must have valid frame IDs. */
6847 /* The outer_frame_id check is a heuristic to detect stepping
6848 through startup code. If we step over an instruction which
6849 sets the stack pointer from an invalid value to a valid value,
6850 we may detect that as a subroutine call from the mythical
6851 "outermost" function. This could be fixed by marking
6852 outermost frames as !stack_p,code_p,special_p. Then the
6853 initial outermost frame, before sp was valid, would
6854 have code_addr == &_start. See the comment in frame_id_eq
6856 if (!frame_id_eq (get_stack_frame_id (frame
),
6857 ecs
->event_thread
->control
.step_stack_frame_id
)
6858 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6859 ecs
->event_thread
->control
.step_stack_frame_id
)
6860 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
6862 || (ecs
->event_thread
->control
.step_start_function
6863 != find_pc_function (ecs
->event_thread
->stop_pc ())))))
6865 CORE_ADDR stop_pc
= ecs
->event_thread
->stop_pc ();
6866 CORE_ADDR real_stop_pc
;
6868 infrun_debug_printf ("stepped into subroutine");
6870 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
6872 /* I presume that step_over_calls is only 0 when we're
6873 supposed to be stepping at the assembly language level
6874 ("stepi"). Just stop. */
6875 /* And this works the same backward as frontward. MVS */
6876 end_stepping_range (ecs
);
6880 /* Reverse stepping through solib trampolines. */
6882 if (execution_direction
== EXEC_REVERSE
6883 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6884 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6885 || (ecs
->stop_func_start
== 0
6886 && in_solib_dynsym_resolve_code (stop_pc
))))
6888 /* Any solib trampoline code can be handled in reverse
6889 by simply continuing to single-step. We have already
6890 executed the solib function (backwards), and a few
6891 steps will take us back through the trampoline to the
6897 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6899 /* We're doing a "next".
6901 Normal (forward) execution: set a breakpoint at the
6902 callee's return address (the address at which the caller
6905 Reverse (backward) execution. set the step-resume
6906 breakpoint at the start of the function that we just
6907 stepped into (backwards), and continue to there. When we
6908 get there, we'll need to single-step back to the caller. */
6910 if (execution_direction
== EXEC_REVERSE
)
6912 /* If we're already at the start of the function, we've either
6913 just stepped backward into a single instruction function,
6914 or stepped back out of a signal handler to the first instruction
6915 of the function. Just keep going, which will single-step back
6917 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
6919 /* Normal function call return (static or dynamic). */
6920 symtab_and_line sr_sal
;
6921 sr_sal
.pc
= ecs
->stop_func_start
;
6922 sr_sal
.pspace
= get_frame_program_space (frame
);
6923 insert_step_resume_breakpoint_at_sal (gdbarch
,
6924 sr_sal
, null_frame_id
);
6928 insert_step_resume_breakpoint_at_caller (frame
);
6934 /* If we are in a function call trampoline (a stub between the
6935 calling routine and the real function), locate the real
6936 function. That's what tells us (a) whether we want to step
6937 into it at all, and (b) what prologue we want to run to the
6938 end of, if we do step into it. */
6939 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
6940 if (real_stop_pc
== 0)
6941 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6942 if (real_stop_pc
!= 0)
6943 ecs
->stop_func_start
= real_stop_pc
;
6945 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
6947 symtab_and_line sr_sal
;
6948 sr_sal
.pc
= ecs
->stop_func_start
;
6949 sr_sal
.pspace
= get_frame_program_space (frame
);
6951 insert_step_resume_breakpoint_at_sal (gdbarch
,
6952 sr_sal
, null_frame_id
);
6957 /* If we have line number information for the function we are
6958 thinking of stepping into and the function isn't on the skip
6961 If there are several symtabs at that PC (e.g. with include
6962 files), just want to know whether *any* of them have line
6963 numbers. find_pc_line handles this. */
6965 struct symtab_and_line tmp_sal
;
6967 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
6968 if (tmp_sal
.line
!= 0
6969 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
6971 && !inline_frame_is_marked_for_skip (true, ecs
->event_thread
))
6973 if (execution_direction
== EXEC_REVERSE
)
6974 handle_step_into_function_backward (gdbarch
, ecs
);
6976 handle_step_into_function (gdbarch
, ecs
);
6981 /* If we have no line number and the step-stop-if-no-debug is
6982 set, we stop the step so that the user has a chance to switch
6983 in assembly mode. */
6984 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6985 && step_stop_if_no_debug
)
6987 end_stepping_range (ecs
);
6991 if (execution_direction
== EXEC_REVERSE
)
6993 /* If we're already at the start of the function, we've either just
6994 stepped backward into a single instruction function without line
6995 number info, or stepped back out of a signal handler to the first
6996 instruction of the function without line number info. Just keep
6997 going, which will single-step back to the caller. */
6998 if (ecs
->stop_func_start
!= stop_pc
)
7000 /* Set a breakpoint at callee's start address.
7001 From there we can step once and be back in the caller. */
7002 symtab_and_line sr_sal
;
7003 sr_sal
.pc
= ecs
->stop_func_start
;
7004 sr_sal
.pspace
= get_frame_program_space (frame
);
7005 insert_step_resume_breakpoint_at_sal (gdbarch
,
7006 sr_sal
, null_frame_id
);
7010 /* Set a breakpoint at callee's return address (the address
7011 at which the caller will resume). */
7012 insert_step_resume_breakpoint_at_caller (frame
);
7018 /* Reverse stepping through solib trampolines. */
7020 if (execution_direction
== EXEC_REVERSE
7021 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
7023 CORE_ADDR stop_pc
= ecs
->event_thread
->stop_pc ();
7025 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
7026 || (ecs
->stop_func_start
== 0
7027 && in_solib_dynsym_resolve_code (stop_pc
)))
7029 /* Any solib trampoline code can be handled in reverse
7030 by simply continuing to single-step. We have already
7031 executed the solib function (backwards), and a few
7032 steps will take us back through the trampoline to the
7037 else if (in_solib_dynsym_resolve_code (stop_pc
))
7039 /* Stepped backward into the solib dynsym resolver.
7040 Set a breakpoint at its start and continue, then
7041 one more step will take us out. */
7042 symtab_and_line sr_sal
;
7043 sr_sal
.pc
= ecs
->stop_func_start
;
7044 sr_sal
.pspace
= get_frame_program_space (frame
);
7045 insert_step_resume_breakpoint_at_sal (gdbarch
,
7046 sr_sal
, null_frame_id
);
7052 /* This always returns the sal for the inner-most frame when we are in a
7053 stack of inlined frames, even if GDB actually believes that it is in a
7054 more outer frame. This is checked for below by calls to
7055 inline_skipped_frames. */
7056 stop_pc_sal
= find_pc_line (ecs
->event_thread
->stop_pc (), 0);
7058 /* NOTE: tausq/2004-05-24: This if block used to be done before all
7059 the trampoline processing logic, however, there are some trampolines
7060 that have no names, so we should do trampoline handling first. */
7061 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
7062 && ecs
->stop_func_name
== NULL
7063 && stop_pc_sal
.line
== 0)
7065 infrun_debug_printf ("stepped into undebuggable function");
7067 /* The inferior just stepped into, or returned to, an
7068 undebuggable function (where there is no debugging information
7069 and no line number corresponding to the address where the
7070 inferior stopped). Since we want to skip this kind of code,
7071 we keep going until the inferior returns from this
7072 function - unless the user has asked us not to (via
7073 set step-mode) or we no longer know how to get back
7074 to the call site. */
7075 if (step_stop_if_no_debug
7076 || !frame_id_p (frame_unwind_caller_id (frame
)))
7078 /* If we have no line number and the step-stop-if-no-debug
7079 is set, we stop the step so that the user has a chance to
7080 switch in assembly mode. */
7081 end_stepping_range (ecs
);
7086 /* Set a breakpoint at callee's return address (the address
7087 at which the caller will resume). */
7088 insert_step_resume_breakpoint_at_caller (frame
);
7094 if (ecs
->event_thread
->control
.step_range_end
== 1)
7096 /* It is stepi or nexti. We always want to stop stepping after
7098 infrun_debug_printf ("stepi/nexti");
7099 end_stepping_range (ecs
);
7103 if (stop_pc_sal
.line
== 0)
7105 /* We have no line number information. That means to stop
7106 stepping (does this always happen right after one instruction,
7107 when we do "s" in a function with no line numbers,
7108 or can this happen as a result of a return or longjmp?). */
7109 infrun_debug_printf ("line number info");
7110 end_stepping_range (ecs
);
7114 /* Look for "calls" to inlined functions, part one. If the inline
7115 frame machinery detected some skipped call sites, we have entered
7116 a new inline function. */
7118 if (frame_id_eq (get_frame_id (get_current_frame ()),
7119 ecs
->event_thread
->control
.step_frame_id
)
7120 && inline_skipped_frames (ecs
->event_thread
))
7122 infrun_debug_printf ("stepped into inlined function");
7124 symtab_and_line call_sal
= find_frame_sal (get_current_frame ());
7126 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
7128 /* For "step", we're going to stop. But if the call site
7129 for this inlined function is on the same source line as
7130 we were previously stepping, go down into the function
7131 first. Otherwise stop at the call site. */
7133 if (call_sal
.line
== ecs
->event_thread
->current_line
7134 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
7136 step_into_inline_frame (ecs
->event_thread
);
7137 if (inline_frame_is_marked_for_skip (false, ecs
->event_thread
))
7144 end_stepping_range (ecs
);
7149 /* For "next", we should stop at the call site if it is on a
7150 different source line. Otherwise continue through the
7151 inlined function. */
7152 if (call_sal
.line
== ecs
->event_thread
->current_line
7153 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
7156 end_stepping_range (ecs
);
7161 /* Look for "calls" to inlined functions, part two. If we are still
7162 in the same real function we were stepping through, but we have
7163 to go further up to find the exact frame ID, we are stepping
7164 through a more inlined call beyond its call site. */
7166 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
7167 && !frame_id_eq (get_frame_id (get_current_frame ()),
7168 ecs
->event_thread
->control
.step_frame_id
)
7169 && stepped_in_from (get_current_frame (),
7170 ecs
->event_thread
->control
.step_frame_id
))
7172 infrun_debug_printf ("stepping through inlined function");
7174 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
7175 || inline_frame_is_marked_for_skip (false, ecs
->event_thread
))
7178 end_stepping_range (ecs
);
7182 bool refresh_step_info
= true;
7183 if ((ecs
->event_thread
->stop_pc () == stop_pc_sal
.pc
)
7184 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
7185 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
7187 /* We are at a different line. */
7189 if (stop_pc_sal
.is_stmt
)
7191 /* We are at the start of a statement.
7193 So stop. Note that we don't stop if we step into the middle of a
7194 statement. That is said to make things like for (;;) statements
7196 infrun_debug_printf ("stepped to a different line");
7197 end_stepping_range (ecs
);
7200 else if (frame_id_eq (get_frame_id (get_current_frame ()),
7201 ecs
->event_thread
->control
.step_frame_id
))
7203 /* We are not at the start of a statement, and we have not changed
7206 We ignore this line table entry, and continue stepping forward,
7207 looking for a better place to stop. */
7208 refresh_step_info
= false;
7209 infrun_debug_printf ("stepped to a different line, but "
7210 "it's not the start of a statement");
7214 /* We are not the start of a statement, and we have changed frame.
7216 We ignore this line table entry, and continue stepping forward,
7217 looking for a better place to stop. Keep refresh_step_info at
7218 true to note that the frame has changed, but ignore the line
7219 number to make sure we don't ignore a subsequent entry with the
7220 same line number. */
7221 stop_pc_sal
.line
= 0;
7222 infrun_debug_printf ("stepped to a different frame, but "
7223 "it's not the start of a statement");
7227 /* We aren't done stepping.
7229 Optimize by setting the stepping range to the line.
7230 (We might not be in the original line, but if we entered a
7231 new line in mid-statement, we continue stepping. This makes
7232 things like for(;;) statements work better.)
7234 If we entered a SAL that indicates a non-statement line table entry,
7235 then we update the stepping range, but we don't update the step info,
7236 which includes things like the line number we are stepping away from.
7237 This means we will stop when we find a line table entry that is marked
7238 as is-statement, even if it matches the non-statement one we just
7241 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
7242 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
7243 ecs
->event_thread
->control
.may_range_step
= 1;
7244 if (refresh_step_info
)
7245 set_step_info (ecs
->event_thread
, frame
, stop_pc_sal
);
7247 infrun_debug_printf ("keep going");
7251 static bool restart_stepped_thread (process_stratum_target
*resume_target
,
7252 ptid_t resume_ptid
);
7254 /* In all-stop mode, if we're currently stepping but have stopped in
7255 some other thread, we may need to switch back to the stepped
7256 thread. Returns true we set the inferior running, false if we left
7257 it stopped (and the event needs further processing). */
7260 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
7262 if (!target_is_non_stop_p ())
7264 /* If any thread is blocked on some internal breakpoint, and we
7265 simply need to step over that breakpoint to get it going
7266 again, do that first. */
7268 /* However, if we see an event for the stepping thread, then we
7269 know all other threads have been moved past their breakpoints
7270 already. Let the caller check whether the step is finished,
7271 etc., before deciding to move it past a breakpoint. */
7272 if (ecs
->event_thread
->control
.step_range_end
!= 0)
7275 /* Check if the current thread is blocked on an incomplete
7276 step-over, interrupted by a random signal. */
7277 if (ecs
->event_thread
->control
.trap_expected
7278 && ecs
->event_thread
->stop_signal () != GDB_SIGNAL_TRAP
)
7281 ("need to finish step-over of [%s]",
7282 target_pid_to_str (ecs
->event_thread
->ptid
).c_str ());
7287 /* Check if the current thread is blocked by a single-step
7288 breakpoint of another thread. */
7289 if (ecs
->hit_singlestep_breakpoint
)
7291 infrun_debug_printf ("need to step [%s] over single-step breakpoint",
7292 target_pid_to_str (ecs
->ptid
).c_str ());
7297 /* If this thread needs yet another step-over (e.g., stepping
7298 through a delay slot), do it first before moving on to
7300 if (thread_still_needs_step_over (ecs
->event_thread
))
7303 ("thread [%s] still needs step-over",
7304 target_pid_to_str (ecs
->event_thread
->ptid
).c_str ());
7309 /* If scheduler locking applies even if not stepping, there's no
7310 need to walk over threads. Above we've checked whether the
7311 current thread is stepping. If some other thread not the
7312 event thread is stepping, then it must be that scheduler
7313 locking is not in effect. */
7314 if (schedlock_applies (ecs
->event_thread
))
7317 /* Otherwise, we no longer expect a trap in the current thread.
7318 Clear the trap_expected flag before switching back -- this is
7319 what keep_going does as well, if we call it. */
7320 ecs
->event_thread
->control
.trap_expected
= 0;
7322 /* Likewise, clear the signal if it should not be passed. */
7323 if (!signal_program
[ecs
->event_thread
->stop_signal ()])
7324 ecs
->event_thread
->set_stop_signal (GDB_SIGNAL_0
);
7326 if (restart_stepped_thread (ecs
->target
, ecs
->ptid
))
7328 prepare_to_wait (ecs
);
7332 switch_to_thread (ecs
->event_thread
);
7338 /* Look for the thread that was stepping, and resume it.
7339 RESUME_TARGET / RESUME_PTID indicate the set of threads the caller
7340 is resuming. Return true if a thread was started, false
7344 restart_stepped_thread (process_stratum_target
*resume_target
,
7347 /* Do all pending step-overs before actually proceeding with
7349 if (start_step_over ())
7352 for (thread_info
*tp
: all_threads_safe ())
7354 if (tp
->state
== THREAD_EXITED
)
7357 if (tp
->has_pending_waitstatus ())
7360 /* Ignore threads of processes the caller is not
7363 && (tp
->inf
->process_target () != resume_target
7364 || tp
->inf
->pid
!= resume_ptid
.pid ()))
7367 if (tp
->control
.trap_expected
)
7369 infrun_debug_printf ("switching back to stepped thread (step-over)");
7371 if (keep_going_stepped_thread (tp
))
7376 for (thread_info
*tp
: all_threads_safe ())
7378 if (tp
->state
== THREAD_EXITED
)
7381 if (tp
->has_pending_waitstatus ())
7384 /* Ignore threads of processes the caller is not
7387 && (tp
->inf
->process_target () != resume_target
7388 || tp
->inf
->pid
!= resume_ptid
.pid ()))
7391 /* Did we find the stepping thread? */
7392 if (tp
->control
.step_range_end
)
7394 infrun_debug_printf ("switching back to stepped thread (stepping)");
7396 if (keep_going_stepped_thread (tp
))
7407 restart_after_all_stop_detach (process_stratum_target
*proc_target
)
7409 /* Note we don't check target_is_non_stop_p() here, because the
7410 current inferior may no longer have a process_stratum target
7411 pushed, as we just detached. */
7413 /* See if we have a THREAD_RUNNING thread that need to be
7414 re-resumed. If we have any thread that is already executing,
7415 then we don't need to resume the target -- it is already been
7416 resumed. With the remote target (in all-stop), it's even
7417 impossible to issue another resumption if the target is already
7418 resumed, until the target reports a stop. */
7419 for (thread_info
*thr
: all_threads (proc_target
))
7421 if (thr
->state
!= THREAD_RUNNING
)
7424 /* If we have any thread that is already executing, then we
7425 don't need to resume the target -- it is already been
7430 /* If we have a pending event to process, skip resuming the
7431 target and go straight to processing it. */
7432 if (thr
->resumed () && thr
->has_pending_waitstatus ())
7436 /* Alright, we need to re-resume the target. If a thread was
7437 stepping, we need to restart it stepping. */
7438 if (restart_stepped_thread (proc_target
, minus_one_ptid
))
7441 /* Otherwise, find the first THREAD_RUNNING thread and resume
7443 for (thread_info
*thr
: all_threads (proc_target
))
7445 if (thr
->state
!= THREAD_RUNNING
)
7448 execution_control_state ecs
;
7449 reset_ecs (&ecs
, thr
);
7450 switch_to_thread (thr
);
7456 /* Set a previously stepped thread back to stepping. Returns true on
7457 success, false if the resume is not possible (e.g., the thread
7461 keep_going_stepped_thread (struct thread_info
*tp
)
7463 struct frame_info
*frame
;
7464 struct execution_control_state ecss
;
7465 struct execution_control_state
*ecs
= &ecss
;
7467 /* If the stepping thread exited, then don't try to switch back and
7468 resume it, which could fail in several different ways depending
7469 on the target. Instead, just keep going.
7471 We can find a stepping dead thread in the thread list in two
7474 - The target supports thread exit events, and when the target
7475 tries to delete the thread from the thread list, inferior_ptid
7476 pointed at the exiting thread. In such case, calling
7477 delete_thread does not really remove the thread from the list;
7478 instead, the thread is left listed, with 'exited' state.
7480 - The target's debug interface does not support thread exit
7481 events, and so we have no idea whatsoever if the previously
7482 stepping thread is still alive. For that reason, we need to
7483 synchronously query the target now. */
7485 if (tp
->state
== THREAD_EXITED
|| !target_thread_alive (tp
->ptid
))
7487 infrun_debug_printf ("not resuming previously stepped thread, it has "
7494 infrun_debug_printf ("resuming previously stepped thread");
7496 reset_ecs (ecs
, tp
);
7497 switch_to_thread (tp
);
7499 tp
->set_stop_pc (regcache_read_pc (get_thread_regcache (tp
)));
7500 frame
= get_current_frame ();
7502 /* If the PC of the thread we were trying to single-step has
7503 changed, then that thread has trapped or been signaled, but the
7504 event has not been reported to GDB yet. Re-poll the target
7505 looking for this particular thread's event (i.e. temporarily
7506 enable schedlock) by:
7508 - setting a break at the current PC
7509 - resuming that particular thread, only (by setting trap
7512 This prevents us continuously moving the single-step breakpoint
7513 forward, one instruction at a time, overstepping. */
7515 if (tp
->stop_pc () != tp
->prev_pc
)
7519 infrun_debug_printf ("expected thread advanced also (%s -> %s)",
7520 paddress (target_gdbarch (), tp
->prev_pc
),
7521 paddress (target_gdbarch (), tp
->stop_pc ()));
7523 /* Clear the info of the previous step-over, as it's no longer
7524 valid (if the thread was trying to step over a breakpoint, it
7525 has already succeeded). It's what keep_going would do too,
7526 if we called it. Do this before trying to insert the sss
7527 breakpoint, otherwise if we were previously trying to step
7528 over this exact address in another thread, the breakpoint is
7530 clear_step_over_info ();
7531 tp
->control
.trap_expected
= 0;
7533 insert_single_step_breakpoint (get_frame_arch (frame
),
7534 get_frame_address_space (frame
),
7537 tp
->set_resumed (true);
7538 resume_ptid
= internal_resume_ptid (tp
->control
.stepping_command
);
7539 do_target_resume (resume_ptid
, false, GDB_SIGNAL_0
);
7543 infrun_debug_printf ("expected thread still hasn't advanced");
7545 keep_going_pass_signal (ecs
);
7551 /* Is thread TP in the middle of (software or hardware)
7552 single-stepping? (Note the result of this function must never be
7553 passed directly as target_resume's STEP parameter.) */
7556 currently_stepping (struct thread_info
*tp
)
7558 return ((tp
->control
.step_range_end
7559 && tp
->control
.step_resume_breakpoint
== NULL
)
7560 || tp
->control
.trap_expected
7561 || tp
->stepped_breakpoint
7562 || bpstat_should_step ());
7565 /* Inferior has stepped into a subroutine call with source code that
7566 we should not step over. Do step to the first line of code in
7570 handle_step_into_function (struct gdbarch
*gdbarch
,
7571 struct execution_control_state
*ecs
)
7573 fill_in_stop_func (gdbarch
, ecs
);
7575 compunit_symtab
*cust
7576 = find_pc_compunit_symtab (ecs
->event_thread
->stop_pc ());
7577 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7578 ecs
->stop_func_start
7579 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7581 symtab_and_line stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7582 /* Use the step_resume_break to step until the end of the prologue,
7583 even if that involves jumps (as it seems to on the vax under
7585 /* If the prologue ends in the middle of a source line, continue to
7586 the end of that source line (if it is still within the function).
7587 Otherwise, just go to end of prologue. */
7588 if (stop_func_sal
.end
7589 && stop_func_sal
.pc
!= ecs
->stop_func_start
7590 && stop_func_sal
.end
< ecs
->stop_func_end
)
7591 ecs
->stop_func_start
= stop_func_sal
.end
;
7593 /* Architectures which require breakpoint adjustment might not be able
7594 to place a breakpoint at the computed address. If so, the test
7595 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7596 ecs->stop_func_start to an address at which a breakpoint may be
7597 legitimately placed.
7599 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7600 made, GDB will enter an infinite loop when stepping through
7601 optimized code consisting of VLIW instructions which contain
7602 subinstructions corresponding to different source lines. On
7603 FR-V, it's not permitted to place a breakpoint on any but the
7604 first subinstruction of a VLIW instruction. When a breakpoint is
7605 set, GDB will adjust the breakpoint address to the beginning of
7606 the VLIW instruction. Thus, we need to make the corresponding
7607 adjustment here when computing the stop address. */
7609 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
7611 ecs
->stop_func_start
7612 = gdbarch_adjust_breakpoint_address (gdbarch
,
7613 ecs
->stop_func_start
);
7616 if (ecs
->stop_func_start
== ecs
->event_thread
->stop_pc ())
7618 /* We are already there: stop now. */
7619 end_stepping_range (ecs
);
7624 /* Put the step-breakpoint there and go until there. */
7625 symtab_and_line sr_sal
;
7626 sr_sal
.pc
= ecs
->stop_func_start
;
7627 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
7628 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
7630 /* Do not specify what the fp should be when we stop since on
7631 some machines the prologue is where the new fp value is
7633 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
7635 /* And make sure stepping stops right away then. */
7636 ecs
->event_thread
->control
.step_range_end
7637 = ecs
->event_thread
->control
.step_range_start
;
7642 /* Inferior has stepped backward into a subroutine call with source
7643 code that we should not step over. Do step to the beginning of the
7644 last line of code in it. */
7647 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
7648 struct execution_control_state
*ecs
)
7650 struct compunit_symtab
*cust
;
7651 struct symtab_and_line stop_func_sal
;
7653 fill_in_stop_func (gdbarch
, ecs
);
7655 cust
= find_pc_compunit_symtab (ecs
->event_thread
->stop_pc ());
7656 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7657 ecs
->stop_func_start
7658 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7660 stop_func_sal
= find_pc_line (ecs
->event_thread
->stop_pc (), 0);
7662 /* OK, we're just going to keep stepping here. */
7663 if (stop_func_sal
.pc
== ecs
->event_thread
->stop_pc ())
7665 /* We're there already. Just stop stepping now. */
7666 end_stepping_range (ecs
);
7670 /* Else just reset the step range and keep going.
7671 No step-resume breakpoint, they don't work for
7672 epilogues, which can have multiple entry paths. */
7673 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
7674 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
7680 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7681 This is used to both functions and to skip over code. */
7684 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
7685 struct symtab_and_line sr_sal
,
7686 struct frame_id sr_id
,
7687 enum bptype sr_type
)
7689 /* There should never be more than one step-resume or longjmp-resume
7690 breakpoint per thread, so we should never be setting a new
7691 step_resume_breakpoint when one is already active. */
7692 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
7693 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
7695 infrun_debug_printf ("inserting step-resume breakpoint at %s",
7696 paddress (gdbarch
, sr_sal
.pc
));
7698 inferior_thread ()->control
.step_resume_breakpoint
7699 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
).release ();
7703 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
7704 struct symtab_and_line sr_sal
,
7705 struct frame_id sr_id
)
7707 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
7712 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7713 This is used to skip a potential signal handler.
7715 This is called with the interrupted function's frame. The signal
7716 handler, when it returns, will resume the interrupted function at
7720 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
7722 gdb_assert (return_frame
!= NULL
);
7724 struct gdbarch
*gdbarch
= get_frame_arch (return_frame
);
7726 symtab_and_line sr_sal
;
7727 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
7728 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7729 sr_sal
.pspace
= get_frame_program_space (return_frame
);
7731 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
7732 get_stack_frame_id (return_frame
),
7736 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7737 is used to skip a function after stepping into it (for "next" or if
7738 the called function has no debugging information).
7740 The current function has almost always been reached by single
7741 stepping a call or return instruction. NEXT_FRAME belongs to the
7742 current function, and the breakpoint will be set at the caller's
7745 This is a separate function rather than reusing
7746 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7747 get_prev_frame, which may stop prematurely (see the implementation
7748 of frame_unwind_caller_id for an example). */
7751 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
7753 /* We shouldn't have gotten here if we don't know where the call site
7755 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
7757 struct gdbarch
*gdbarch
= frame_unwind_caller_arch (next_frame
);
7759 symtab_and_line sr_sal
;
7760 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
7761 frame_unwind_caller_pc (next_frame
));
7762 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7763 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
7765 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
7766 frame_unwind_caller_id (next_frame
));
7769 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7770 new breakpoint at the target of a jmp_buf. The handling of
7771 longjmp-resume uses the same mechanisms used for handling
7772 "step-resume" breakpoints. */
7775 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
7777 /* There should never be more than one longjmp-resume breakpoint per
7778 thread, so we should never be setting a new
7779 longjmp_resume_breakpoint when one is already active. */
7780 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
7782 infrun_debug_printf ("inserting longjmp-resume breakpoint at %s",
7783 paddress (gdbarch
, pc
));
7785 inferior_thread ()->control
.exception_resume_breakpoint
=
7786 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
).release ();
7789 /* Insert an exception resume breakpoint. TP is the thread throwing
7790 the exception. The block B is the block of the unwinder debug hook
7791 function. FRAME is the frame corresponding to the call to this
7792 function. SYM is the symbol of the function argument holding the
7793 target PC of the exception. */
7796 insert_exception_resume_breakpoint (struct thread_info
*tp
,
7797 const struct block
*b
,
7798 struct frame_info
*frame
,
7803 struct block_symbol vsym
;
7804 struct value
*value
;
7806 struct breakpoint
*bp
;
7808 vsym
= lookup_symbol_search_name (sym
->search_name (),
7810 value
= read_var_value (vsym
.symbol
, vsym
.block
, frame
);
7811 /* If the value was optimized out, revert to the old behavior. */
7812 if (! value_optimized_out (value
))
7814 handler
= value_as_address (value
);
7816 infrun_debug_printf ("exception resume at %lx",
7817 (unsigned long) handler
);
7819 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7821 bp_exception_resume
).release ();
7823 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7826 bp
->thread
= tp
->global_num
;
7827 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7830 catch (const gdb_exception_error
&e
)
7832 /* We want to ignore errors here. */
7836 /* A helper for check_exception_resume that sets an
7837 exception-breakpoint based on a SystemTap probe. */
7840 insert_exception_resume_from_probe (struct thread_info
*tp
,
7841 const struct bound_probe
*probe
,
7842 struct frame_info
*frame
)
7844 struct value
*arg_value
;
7846 struct breakpoint
*bp
;
7848 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
7852 handler
= value_as_address (arg_value
);
7854 infrun_debug_printf ("exception resume at %s",
7855 paddress (probe
->objfile
->arch (), handler
));
7857 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7858 handler
, bp_exception_resume
).release ();
7859 bp
->thread
= tp
->global_num
;
7860 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7863 /* This is called when an exception has been intercepted. Check to
7864 see whether the exception's destination is of interest, and if so,
7865 set an exception resume breakpoint there. */
7868 check_exception_resume (struct execution_control_state
*ecs
,
7869 struct frame_info
*frame
)
7871 struct bound_probe probe
;
7872 struct symbol
*func
;
7874 /* First see if this exception unwinding breakpoint was set via a
7875 SystemTap probe point. If so, the probe has two arguments: the
7876 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7877 set a breakpoint there. */
7878 probe
= find_probe_by_pc (get_frame_pc (frame
));
7881 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
7885 func
= get_frame_function (frame
);
7891 const struct block
*b
;
7892 struct block_iterator iter
;
7896 /* The exception breakpoint is a thread-specific breakpoint on
7897 the unwinder's debug hook, declared as:
7899 void _Unwind_DebugHook (void *cfa, void *handler);
7901 The CFA argument indicates the frame to which control is
7902 about to be transferred. HANDLER is the destination PC.
7904 We ignore the CFA and set a temporary breakpoint at HANDLER.
7905 This is not extremely efficient but it avoids issues in gdb
7906 with computing the DWARF CFA, and it also works even in weird
7907 cases such as throwing an exception from inside a signal
7910 b
= SYMBOL_BLOCK_VALUE (func
);
7911 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
7913 if (!SYMBOL_IS_ARGUMENT (sym
))
7920 insert_exception_resume_breakpoint (ecs
->event_thread
,
7926 catch (const gdb_exception_error
&e
)
7932 stop_waiting (struct execution_control_state
*ecs
)
7934 infrun_debug_printf ("stop_waiting");
7936 /* Let callers know we don't want to wait for the inferior anymore. */
7937 ecs
->wait_some_more
= 0;
7939 /* If all-stop, but there exists a non-stop target, stop all
7940 threads now that we're presenting the stop to the user. */
7941 if (!non_stop
&& exists_non_stop_target ())
7942 stop_all_threads ();
7945 /* Like keep_going, but passes the signal to the inferior, even if the
7946 signal is set to nopass. */
7949 keep_going_pass_signal (struct execution_control_state
*ecs
)
7951 gdb_assert (ecs
->event_thread
->ptid
== inferior_ptid
);
7952 gdb_assert (!ecs
->event_thread
->resumed ());
7954 /* Save the pc before execution, to compare with pc after stop. */
7955 ecs
->event_thread
->prev_pc
7956 = regcache_read_pc_protected (get_thread_regcache (ecs
->event_thread
));
7958 if (ecs
->event_thread
->control
.trap_expected
)
7960 struct thread_info
*tp
= ecs
->event_thread
;
7962 infrun_debug_printf ("%s has trap_expected set, "
7963 "resuming to collect trap",
7964 target_pid_to_str (tp
->ptid
).c_str ());
7966 /* We haven't yet gotten our trap, and either: intercepted a
7967 non-signal event (e.g., a fork); or took a signal which we
7968 are supposed to pass through to the inferior. Simply
7970 resume (ecs
->event_thread
->stop_signal ());
7972 else if (step_over_info_valid_p ())
7974 /* Another thread is stepping over a breakpoint in-line. If
7975 this thread needs a step-over too, queue the request. In
7976 either case, this resume must be deferred for later. */
7977 struct thread_info
*tp
= ecs
->event_thread
;
7979 if (ecs
->hit_singlestep_breakpoint
7980 || thread_still_needs_step_over (tp
))
7982 infrun_debug_printf ("step-over already in progress: "
7983 "step-over for %s deferred",
7984 target_pid_to_str (tp
->ptid
).c_str ());
7985 global_thread_step_over_chain_enqueue (tp
);
7989 infrun_debug_printf ("step-over in progress: resume of %s deferred",
7990 target_pid_to_str (tp
->ptid
).c_str ());
7995 struct regcache
*regcache
= get_current_regcache ();
7998 step_over_what step_what
;
8000 /* Either the trap was not expected, but we are continuing
8001 anyway (if we got a signal, the user asked it be passed to
8004 We got our expected trap, but decided we should resume from
8007 We're going to run this baby now!
8009 Note that insert_breakpoints won't try to re-insert
8010 already inserted breakpoints. Therefore, we don't
8011 care if breakpoints were already inserted, or not. */
8013 /* If we need to step over a breakpoint, and we're not using
8014 displaced stepping to do so, insert all breakpoints
8015 (watchpoints, etc.) but the one we're stepping over, step one
8016 instruction, and then re-insert the breakpoint when that step
8019 step_what
= thread_still_needs_step_over (ecs
->event_thread
);
8021 remove_bp
= (ecs
->hit_singlestep_breakpoint
8022 || (step_what
& STEP_OVER_BREAKPOINT
));
8023 remove_wps
= (step_what
& STEP_OVER_WATCHPOINT
);
8025 /* We can't use displaced stepping if we need to step past a
8026 watchpoint. The instruction copied to the scratch pad would
8027 still trigger the watchpoint. */
8029 && (remove_wps
|| !use_displaced_stepping (ecs
->event_thread
)))
8031 set_step_over_info (regcache
->aspace (),
8032 regcache_read_pc (regcache
), remove_wps
,
8033 ecs
->event_thread
->global_num
);
8035 else if (remove_wps
)
8036 set_step_over_info (NULL
, 0, remove_wps
, -1);
8038 /* If we now need to do an in-line step-over, we need to stop
8039 all other threads. Note this must be done before
8040 insert_breakpoints below, because that removes the breakpoint
8041 we're about to step over, otherwise other threads could miss
8043 if (step_over_info_valid_p () && target_is_non_stop_p ())
8044 stop_all_threads ();
8046 /* Stop stepping if inserting breakpoints fails. */
8049 insert_breakpoints ();
8051 catch (const gdb_exception_error
&e
)
8053 exception_print (gdb_stderr
, e
);
8055 clear_step_over_info ();
8059 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
8061 resume (ecs
->event_thread
->stop_signal ());
8064 prepare_to_wait (ecs
);
8067 /* Called when we should continue running the inferior, because the
8068 current event doesn't cause a user visible stop. This does the
8069 resuming part; waiting for the next event is done elsewhere. */
8072 keep_going (struct execution_control_state
*ecs
)
8074 if (ecs
->event_thread
->control
.trap_expected
8075 && ecs
->event_thread
->stop_signal () == GDB_SIGNAL_TRAP
)
8076 ecs
->event_thread
->control
.trap_expected
= 0;
8078 if (!signal_program
[ecs
->event_thread
->stop_signal ()])
8079 ecs
->event_thread
->set_stop_signal (GDB_SIGNAL_0
);
8080 keep_going_pass_signal (ecs
);
8083 /* This function normally comes after a resume, before
8084 handle_inferior_event exits. It takes care of any last bits of
8085 housekeeping, and sets the all-important wait_some_more flag. */
8088 prepare_to_wait (struct execution_control_state
*ecs
)
8090 infrun_debug_printf ("prepare_to_wait");
8092 ecs
->wait_some_more
= 1;
8094 /* If the target can't async, emulate it by marking the infrun event
8095 handler such that as soon as we get back to the event-loop, we
8096 immediately end up in fetch_inferior_event again calling
8098 if (!target_can_async_p ())
8099 mark_infrun_async_event_handler ();
8102 /* We are done with the step range of a step/next/si/ni command.
8103 Called once for each n of a "step n" operation. */
8106 end_stepping_range (struct execution_control_state
*ecs
)
8108 ecs
->event_thread
->control
.stop_step
= 1;
8112 /* Several print_*_reason functions to print why the inferior has stopped.
8113 We always print something when the inferior exits, or receives a signal.
8114 The rest of the cases are dealt with later on in normal_stop and
8115 print_it_typical. Ideally there should be a call to one of these
8116 print_*_reason functions functions from handle_inferior_event each time
8117 stop_waiting is called.
8119 Note that we don't call these directly, instead we delegate that to
8120 the interpreters, through observers. Interpreters then call these
8121 with whatever uiout is right. */
8124 print_end_stepping_range_reason (struct ui_out
*uiout
)
8126 /* For CLI-like interpreters, print nothing. */
8128 if (uiout
->is_mi_like_p ())
8130 uiout
->field_string ("reason",
8131 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
8136 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
8138 annotate_signalled ();
8139 if (uiout
->is_mi_like_p ())
8141 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
8142 uiout
->text ("\nProgram terminated with signal ");
8143 annotate_signal_name ();
8144 uiout
->field_string ("signal-name",
8145 gdb_signal_to_name (siggnal
));
8146 annotate_signal_name_end ();
8148 annotate_signal_string ();
8149 uiout
->field_string ("signal-meaning",
8150 gdb_signal_to_string (siggnal
));
8151 annotate_signal_string_end ();
8152 uiout
->text (".\n");
8153 uiout
->text ("The program no longer exists.\n");
8157 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
8159 struct inferior
*inf
= current_inferior ();
8160 std::string pidstr
= target_pid_to_str (ptid_t (inf
->pid
));
8162 annotate_exited (exitstatus
);
8165 if (uiout
->is_mi_like_p ())
8166 uiout
->field_string ("reason", async_reason_lookup (EXEC_ASYNC_EXITED
));
8167 std::string exit_code_str
8168 = string_printf ("0%o", (unsigned int) exitstatus
);
8169 uiout
->message ("[Inferior %s (%s) exited with code %pF]\n",
8170 plongest (inf
->num
), pidstr
.c_str (),
8171 string_field ("exit-code", exit_code_str
.c_str ()));
8175 if (uiout
->is_mi_like_p ())
8177 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
8178 uiout
->message ("[Inferior %s (%s) exited normally]\n",
8179 plongest (inf
->num
), pidstr
.c_str ());
8184 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
8186 struct thread_info
*thr
= inferior_thread ();
8190 if (uiout
->is_mi_like_p ())
8192 else if (show_thread_that_caused_stop ())
8196 uiout
->text ("\nThread ");
8197 uiout
->field_string ("thread-id", print_thread_id (thr
));
8199 name
= thr
->name
!= NULL
? thr
->name
: target_thread_name (thr
);
8202 uiout
->text (" \"");
8203 uiout
->field_string ("name", name
);
8208 uiout
->text ("\nProgram");
8210 if (siggnal
== GDB_SIGNAL_0
&& !uiout
->is_mi_like_p ())
8211 uiout
->text (" stopped");
8214 uiout
->text (" received signal ");
8215 annotate_signal_name ();
8216 if (uiout
->is_mi_like_p ())
8218 ("reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
8219 uiout
->field_string ("signal-name", gdb_signal_to_name (siggnal
));
8220 annotate_signal_name_end ();
8222 annotate_signal_string ();
8223 uiout
->field_string ("signal-meaning", gdb_signal_to_string (siggnal
));
8225 struct regcache
*regcache
= get_current_regcache ();
8226 struct gdbarch
*gdbarch
= regcache
->arch ();
8227 if (gdbarch_report_signal_info_p (gdbarch
))
8228 gdbarch_report_signal_info (gdbarch
, uiout
, siggnal
);
8230 annotate_signal_string_end ();
8232 uiout
->text (".\n");
8236 print_no_history_reason (struct ui_out
*uiout
)
8238 uiout
->text ("\nNo more reverse-execution history.\n");
8241 /* Print current location without a level number, if we have changed
8242 functions or hit a breakpoint. Print source line if we have one.
8243 bpstat_print contains the logic deciding in detail what to print,
8244 based on the event(s) that just occurred. */
8247 print_stop_location (struct target_waitstatus
*ws
)
8250 enum print_what source_flag
;
8251 int do_frame_printing
= 1;
8252 struct thread_info
*tp
= inferior_thread ();
8254 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
8258 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
8259 should) carry around the function and does (or should) use
8260 that when doing a frame comparison. */
8261 if (tp
->control
.stop_step
8262 && frame_id_eq (tp
->control
.step_frame_id
,
8263 get_frame_id (get_current_frame ()))
8264 && (tp
->control
.step_start_function
8265 == find_pc_function (tp
->stop_pc ())))
8267 /* Finished step, just print source line. */
8268 source_flag
= SRC_LINE
;
8272 /* Print location and source line. */
8273 source_flag
= SRC_AND_LOC
;
8276 case PRINT_SRC_AND_LOC
:
8277 /* Print location and source line. */
8278 source_flag
= SRC_AND_LOC
;
8280 case PRINT_SRC_ONLY
:
8281 source_flag
= SRC_LINE
;
8284 /* Something bogus. */
8285 source_flag
= SRC_LINE
;
8286 do_frame_printing
= 0;
8289 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
8292 /* The behavior of this routine with respect to the source
8294 SRC_LINE: Print only source line
8295 LOCATION: Print only location
8296 SRC_AND_LOC: Print location and source line. */
8297 if (do_frame_printing
)
8298 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
8304 print_stop_event (struct ui_out
*uiout
, bool displays
)
8306 struct target_waitstatus last
;
8307 struct thread_info
*tp
;
8309 get_last_target_status (nullptr, nullptr, &last
);
8312 scoped_restore save_uiout
= make_scoped_restore (¤t_uiout
, uiout
);
8314 print_stop_location (&last
);
8316 /* Display the auto-display expressions. */
8321 tp
= inferior_thread ();
8322 if (tp
->thread_fsm
!= NULL
8323 && tp
->thread_fsm
->finished_p ())
8325 struct return_value_info
*rv
;
8327 rv
= tp
->thread_fsm
->return_value ();
8329 print_return_value (uiout
, rv
);
8336 maybe_remove_breakpoints (void)
8338 if (!breakpoints_should_be_inserted_now () && target_has_execution ())
8340 if (remove_breakpoints ())
8342 target_terminal::ours_for_output ();
8343 printf_filtered (_("Cannot remove breakpoints because "
8344 "program is no longer writable.\nFurther "
8345 "execution is probably impossible.\n"));
8350 /* The execution context that just caused a normal stop. */
8356 DISABLE_COPY_AND_ASSIGN (stop_context
);
8358 bool changed () const;
8363 /* The event PTID. */
8367 /* If stopp for a thread event, this is the thread that caused the
8369 thread_info_ref thread
;
8371 /* The inferior that caused the stop. */
8375 /* Initializes a new stop context. If stopped for a thread event, this
8376 takes a strong reference to the thread. */
8378 stop_context::stop_context ()
8380 stop_id
= get_stop_id ();
8381 ptid
= inferior_ptid
;
8382 inf_num
= current_inferior ()->num
;
8384 if (inferior_ptid
!= null_ptid
)
8386 /* Take a strong reference so that the thread can't be deleted
8388 thread
= thread_info_ref::new_reference (inferior_thread ());
8392 /* Return true if the current context no longer matches the saved stop
8396 stop_context::changed () const
8398 if (ptid
!= inferior_ptid
)
8400 if (inf_num
!= current_inferior ()->num
)
8402 if (thread
!= NULL
&& thread
->state
!= THREAD_STOPPED
)
8404 if (get_stop_id () != stop_id
)
8414 struct target_waitstatus last
;
8416 get_last_target_status (nullptr, nullptr, &last
);
8420 /* If an exception is thrown from this point on, make sure to
8421 propagate GDB's knowledge of the executing state to the
8422 frontend/user running state. A QUIT is an easy exception to see
8423 here, so do this before any filtered output. */
8425 ptid_t finish_ptid
= null_ptid
;
8428 finish_ptid
= minus_one_ptid
;
8429 else if (last
.kind
== TARGET_WAITKIND_SIGNALLED
8430 || last
.kind
== TARGET_WAITKIND_EXITED
)
8432 /* On some targets, we may still have live threads in the
8433 inferior when we get a process exit event. E.g., for
8434 "checkpoint", when the current checkpoint/fork exits,
8435 linux-fork.c automatically switches to another fork from
8436 within target_mourn_inferior. */
8437 if (inferior_ptid
!= null_ptid
)
8438 finish_ptid
= ptid_t (inferior_ptid
.pid ());
8440 else if (last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8441 finish_ptid
= inferior_ptid
;
8443 gdb::optional
<scoped_finish_thread_state
> maybe_finish_thread_state
;
8444 if (finish_ptid
!= null_ptid
)
8446 maybe_finish_thread_state
.emplace
8447 (user_visible_resume_target (finish_ptid
), finish_ptid
);
8450 /* As we're presenting a stop, and potentially removing breakpoints,
8451 update the thread list so we can tell whether there are threads
8452 running on the target. With target remote, for example, we can
8453 only learn about new threads when we explicitly update the thread
8454 list. Do this before notifying the interpreters about signal
8455 stops, end of stepping ranges, etc., so that the "new thread"
8456 output is emitted before e.g., "Program received signal FOO",
8457 instead of after. */
8458 update_thread_list ();
8460 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
8461 gdb::observers::signal_received
.notify (inferior_thread ()->stop_signal ());
8463 /* As with the notification of thread events, we want to delay
8464 notifying the user that we've switched thread context until
8465 the inferior actually stops.
8467 There's no point in saying anything if the inferior has exited.
8468 Note that SIGNALLED here means "exited with a signal", not
8469 "received a signal".
8471 Also skip saying anything in non-stop mode. In that mode, as we
8472 don't want GDB to switch threads behind the user's back, to avoid
8473 races where the user is typing a command to apply to thread x,
8474 but GDB switches to thread y before the user finishes entering
8475 the command, fetch_inferior_event installs a cleanup to restore
8476 the current thread back to the thread the user had selected right
8477 after this event is handled, so we're not really switching, only
8478 informing of a stop. */
8480 && previous_inferior_ptid
!= inferior_ptid
8481 && target_has_execution ()
8482 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
8483 && last
.kind
!= TARGET_WAITKIND_EXITED
8484 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8486 SWITCH_THRU_ALL_UIS ()
8488 target_terminal::ours_for_output ();
8489 printf_filtered (_("[Switching to %s]\n"),
8490 target_pid_to_str (inferior_ptid
).c_str ());
8491 annotate_thread_changed ();
8493 previous_inferior_ptid
= inferior_ptid
;
8496 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
8498 SWITCH_THRU_ALL_UIS ()
8499 if (current_ui
->prompt_state
== PROMPT_BLOCKED
)
8501 target_terminal::ours_for_output ();
8502 printf_filtered (_("No unwaited-for children left.\n"));
8506 /* Note: this depends on the update_thread_list call above. */
8507 maybe_remove_breakpoints ();
8509 /* If an auto-display called a function and that got a signal,
8510 delete that auto-display to avoid an infinite recursion. */
8512 if (stopped_by_random_signal
)
8513 disable_current_display ();
8515 SWITCH_THRU_ALL_UIS ()
8517 async_enable_stdin ();
8520 /* Let the user/frontend see the threads as stopped. */
8521 maybe_finish_thread_state
.reset ();
8523 /* Select innermost stack frame - i.e., current frame is frame 0,
8524 and current location is based on that. Handle the case where the
8525 dummy call is returning after being stopped. E.g. the dummy call
8526 previously hit a breakpoint. (If the dummy call returns
8527 normally, we won't reach here.) Do this before the stop hook is
8528 run, so that it doesn't get to see the temporary dummy frame,
8529 which is not where we'll present the stop. */
8530 if (has_stack_frames ())
8532 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
8534 /* Pop the empty frame that contains the stack dummy. This
8535 also restores inferior state prior to the call (struct
8536 infcall_suspend_state). */
8537 struct frame_info
*frame
= get_current_frame ();
8539 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
8541 /* frame_pop calls reinit_frame_cache as the last thing it
8542 does which means there's now no selected frame. */
8545 select_frame (get_current_frame ());
8547 /* Set the current source location. */
8548 set_current_sal_from_frame (get_current_frame ());
8551 /* Look up the hook_stop and run it (CLI internally handles problem
8552 of stop_command's pre-hook not existing). */
8553 if (stop_command
!= NULL
)
8555 stop_context saved_context
;
8559 execute_cmd_pre_hook (stop_command
);
8561 catch (const gdb_exception
&ex
)
8563 exception_fprintf (gdb_stderr
, ex
,
8564 "Error while running hook_stop:\n");
8567 /* If the stop hook resumes the target, then there's no point in
8568 trying to notify about the previous stop; its context is
8569 gone. Likewise if the command switches thread or inferior --
8570 the observers would print a stop for the wrong
8572 if (saved_context
.changed ())
8576 /* Notify observers about the stop. This is where the interpreters
8577 print the stop event. */
8578 if (inferior_ptid
!= null_ptid
)
8579 gdb::observers::normal_stop
.notify (inferior_thread ()->control
.stop_bpstat
,
8582 gdb::observers::normal_stop
.notify (NULL
, stop_print_frame
);
8584 annotate_stopped ();
8586 if (target_has_execution ())
8588 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
8589 && last
.kind
!= TARGET_WAITKIND_EXITED
8590 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8591 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8592 Delete any breakpoint that is to be deleted at the next stop. */
8593 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
8596 /* Try to get rid of automatically added inferiors that are no
8597 longer needed. Keeping those around slows down things linearly.
8598 Note that this never removes the current inferior. */
8605 signal_stop_state (int signo
)
8607 return signal_stop
[signo
];
8611 signal_print_state (int signo
)
8613 return signal_print
[signo
];
8617 signal_pass_state (int signo
)
8619 return signal_program
[signo
];
8623 signal_cache_update (int signo
)
8627 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
8628 signal_cache_update (signo
);
8633 signal_pass
[signo
] = (signal_stop
[signo
] == 0
8634 && signal_print
[signo
] == 0
8635 && signal_program
[signo
] == 1
8636 && signal_catch
[signo
] == 0);
8640 signal_stop_update (int signo
, int state
)
8642 int ret
= signal_stop
[signo
];
8644 signal_stop
[signo
] = state
;
8645 signal_cache_update (signo
);
8650 signal_print_update (int signo
, int state
)
8652 int ret
= signal_print
[signo
];
8654 signal_print
[signo
] = state
;
8655 signal_cache_update (signo
);
8660 signal_pass_update (int signo
, int state
)
8662 int ret
= signal_program
[signo
];
8664 signal_program
[signo
] = state
;
8665 signal_cache_update (signo
);
8669 /* Update the global 'signal_catch' from INFO and notify the
8673 signal_catch_update (const unsigned int *info
)
8677 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
8678 signal_catch
[i
] = info
[i
] > 0;
8679 signal_cache_update (-1);
8680 target_pass_signals (signal_pass
);
8684 sig_print_header (void)
8686 printf_filtered (_("Signal Stop\tPrint\tPass "
8687 "to program\tDescription\n"));
8691 sig_print_info (enum gdb_signal oursig
)
8693 const char *name
= gdb_signal_to_name (oursig
);
8694 int name_padding
= 13 - strlen (name
);
8696 if (name_padding
<= 0)
8699 printf_filtered ("%s", name
);
8700 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
8701 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
8702 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
8703 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
8704 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
8707 /* Specify how various signals in the inferior should be handled. */
8710 handle_command (const char *args
, int from_tty
)
8712 int digits
, wordlen
;
8713 int sigfirst
, siglast
;
8714 enum gdb_signal oursig
;
8719 error_no_arg (_("signal to handle"));
8722 /* Allocate and zero an array of flags for which signals to handle. */
8724 const size_t nsigs
= GDB_SIGNAL_LAST
;
8725 unsigned char sigs
[nsigs
] {};
8727 /* Break the command line up into args. */
8729 gdb_argv
built_argv (args
);
8731 /* Walk through the args, looking for signal oursigs, signal names, and
8732 actions. Signal numbers and signal names may be interspersed with
8733 actions, with the actions being performed for all signals cumulatively
8734 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8736 for (char *arg
: built_argv
)
8738 wordlen
= strlen (arg
);
8739 for (digits
= 0; isdigit (arg
[digits
]); digits
++)
8743 sigfirst
= siglast
= -1;
8745 if (wordlen
>= 1 && !strncmp (arg
, "all", wordlen
))
8747 /* Apply action to all signals except those used by the
8748 debugger. Silently skip those. */
8751 siglast
= nsigs
- 1;
8753 else if (wordlen
>= 1 && !strncmp (arg
, "stop", wordlen
))
8755 SET_SIGS (nsigs
, sigs
, signal_stop
);
8756 SET_SIGS (nsigs
, sigs
, signal_print
);
8758 else if (wordlen
>= 1 && !strncmp (arg
, "ignore", wordlen
))
8760 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8762 else if (wordlen
>= 2 && !strncmp (arg
, "print", wordlen
))
8764 SET_SIGS (nsigs
, sigs
, signal_print
);
8766 else if (wordlen
>= 2 && !strncmp (arg
, "pass", wordlen
))
8768 SET_SIGS (nsigs
, sigs
, signal_program
);
8770 else if (wordlen
>= 3 && !strncmp (arg
, "nostop", wordlen
))
8772 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8774 else if (wordlen
>= 3 && !strncmp (arg
, "noignore", wordlen
))
8776 SET_SIGS (nsigs
, sigs
, signal_program
);
8778 else if (wordlen
>= 4 && !strncmp (arg
, "noprint", wordlen
))
8780 UNSET_SIGS (nsigs
, sigs
, signal_print
);
8781 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8783 else if (wordlen
>= 4 && !strncmp (arg
, "nopass", wordlen
))
8785 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8787 else if (digits
> 0)
8789 /* It is numeric. The numeric signal refers to our own
8790 internal signal numbering from target.h, not to host/target
8791 signal number. This is a feature; users really should be
8792 using symbolic names anyway, and the common ones like
8793 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8795 sigfirst
= siglast
= (int)
8796 gdb_signal_from_command (atoi (arg
));
8797 if (arg
[digits
] == '-')
8800 gdb_signal_from_command (atoi (arg
+ digits
+ 1));
8802 if (sigfirst
> siglast
)
8804 /* Bet he didn't figure we'd think of this case... */
8805 std::swap (sigfirst
, siglast
);
8810 oursig
= gdb_signal_from_name (arg
);
8811 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
8813 sigfirst
= siglast
= (int) oursig
;
8817 /* Not a number and not a recognized flag word => complain. */
8818 error (_("Unrecognized or ambiguous flag word: \"%s\"."), arg
);
8822 /* If any signal numbers or symbol names were found, set flags for
8823 which signals to apply actions to. */
8825 for (int signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
8827 switch ((enum gdb_signal
) signum
)
8829 case GDB_SIGNAL_TRAP
:
8830 case GDB_SIGNAL_INT
:
8831 if (!allsigs
&& !sigs
[signum
])
8833 if (query (_("%s is used by the debugger.\n\
8834 Are you sure you want to change it? "),
8835 gdb_signal_to_name ((enum gdb_signal
) signum
)))
8840 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8844 case GDB_SIGNAL_DEFAULT
:
8845 case GDB_SIGNAL_UNKNOWN
:
8846 /* Make sure that "all" doesn't print these. */
8855 for (int signum
= 0; signum
< nsigs
; signum
++)
8858 signal_cache_update (-1);
8859 target_pass_signals (signal_pass
);
8860 target_program_signals (signal_program
);
8864 /* Show the results. */
8865 sig_print_header ();
8866 for (; signum
< nsigs
; signum
++)
8868 sig_print_info ((enum gdb_signal
) signum
);
8875 /* Complete the "handle" command. */
8878 handle_completer (struct cmd_list_element
*ignore
,
8879 completion_tracker
&tracker
,
8880 const char *text
, const char *word
)
8882 static const char * const keywords
[] =
8896 signal_completer (ignore
, tracker
, text
, word
);
8897 complete_on_enum (tracker
, keywords
, word
, word
);
8901 gdb_signal_from_command (int num
)
8903 if (num
>= 1 && num
<= 15)
8904 return (enum gdb_signal
) num
;
8905 error (_("Only signals 1-15 are valid as numeric signals.\n\
8906 Use \"info signals\" for a list of symbolic signals."));
8909 /* Print current contents of the tables set by the handle command.
8910 It is possible we should just be printing signals actually used
8911 by the current target (but for things to work right when switching
8912 targets, all signals should be in the signal tables). */
8915 info_signals_command (const char *signum_exp
, int from_tty
)
8917 enum gdb_signal oursig
;
8919 sig_print_header ();
8923 /* First see if this is a symbol name. */
8924 oursig
= gdb_signal_from_name (signum_exp
);
8925 if (oursig
== GDB_SIGNAL_UNKNOWN
)
8927 /* No, try numeric. */
8929 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
8931 sig_print_info (oursig
);
8935 printf_filtered ("\n");
8936 /* These ugly casts brought to you by the native VAX compiler. */
8937 for (oursig
= GDB_SIGNAL_FIRST
;
8938 (int) oursig
< (int) GDB_SIGNAL_LAST
;
8939 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
8943 if (oursig
!= GDB_SIGNAL_UNKNOWN
8944 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
8945 sig_print_info (oursig
);
8948 printf_filtered (_("\nUse the \"handle\" command "
8949 "to change these tables.\n"));
8952 /* The $_siginfo convenience variable is a bit special. We don't know
8953 for sure the type of the value until we actually have a chance to
8954 fetch the data. The type can change depending on gdbarch, so it is
8955 also dependent on which thread you have selected.
8957 1. making $_siginfo be an internalvar that creates a new value on
8960 2. making the value of $_siginfo be an lval_computed value. */
8962 /* This function implements the lval_computed support for reading a
8966 siginfo_value_read (struct value
*v
)
8968 LONGEST transferred
;
8970 /* If we can access registers, so can we access $_siginfo. Likewise
8972 validate_registers_access ();
8975 target_read (current_inferior ()->top_target (),
8976 TARGET_OBJECT_SIGNAL_INFO
,
8978 value_contents_all_raw (v
),
8980 TYPE_LENGTH (value_type (v
)));
8982 if (transferred
!= TYPE_LENGTH (value_type (v
)))
8983 error (_("Unable to read siginfo"));
8986 /* This function implements the lval_computed support for writing a
8990 siginfo_value_write (struct value
*v
, struct value
*fromval
)
8992 LONGEST transferred
;
8994 /* If we can access registers, so can we access $_siginfo. Likewise
8996 validate_registers_access ();
8998 transferred
= target_write (current_inferior ()->top_target (),
8999 TARGET_OBJECT_SIGNAL_INFO
,
9001 value_contents_all_raw (fromval
),
9003 TYPE_LENGTH (value_type (fromval
)));
9005 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
9006 error (_("Unable to write siginfo"));
9009 static const struct lval_funcs siginfo_value_funcs
=
9015 /* Return a new value with the correct type for the siginfo object of
9016 the current thread using architecture GDBARCH. Return a void value
9017 if there's no object available. */
9019 static struct value
*
9020 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
9023 if (target_has_stack ()
9024 && inferior_ptid
!= null_ptid
9025 && gdbarch_get_siginfo_type_p (gdbarch
))
9027 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
9029 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
9032 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
9036 /* infcall_suspend_state contains state about the program itself like its
9037 registers and any signal it received when it last stopped.
9038 This state must be restored regardless of how the inferior function call
9039 ends (either successfully, or after it hits a breakpoint or signal)
9040 if the program is to properly continue where it left off. */
9042 class infcall_suspend_state
9045 /* Capture state from GDBARCH, TP, and REGCACHE that must be restored
9046 once the inferior function call has finished. */
9047 infcall_suspend_state (struct gdbarch
*gdbarch
,
9048 const struct thread_info
*tp
,
9049 struct regcache
*regcache
)
9050 : m_registers (new readonly_detached_regcache (*regcache
))
9052 tp
->save_suspend_to (m_thread_suspend
);
9054 gdb::unique_xmalloc_ptr
<gdb_byte
> siginfo_data
;
9056 if (gdbarch_get_siginfo_type_p (gdbarch
))
9058 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
9059 size_t len
= TYPE_LENGTH (type
);
9061 siginfo_data
.reset ((gdb_byte
*) xmalloc (len
));
9063 if (target_read (current_inferior ()->top_target (),
9064 TARGET_OBJECT_SIGNAL_INFO
, NULL
,
9065 siginfo_data
.get (), 0, len
) != len
)
9067 /* Errors ignored. */
9068 siginfo_data
.reset (nullptr);
9074 m_siginfo_gdbarch
= gdbarch
;
9075 m_siginfo_data
= std::move (siginfo_data
);
9079 /* Return a pointer to the stored register state. */
9081 readonly_detached_regcache
*registers () const
9083 return m_registers
.get ();
9086 /* Restores the stored state into GDBARCH, TP, and REGCACHE. */
9088 void restore (struct gdbarch
*gdbarch
,
9089 struct thread_info
*tp
,
9090 struct regcache
*regcache
) const
9092 tp
->restore_suspend_from (m_thread_suspend
);
9094 if (m_siginfo_gdbarch
== gdbarch
)
9096 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
9098 /* Errors ignored. */
9099 target_write (current_inferior ()->top_target (),
9100 TARGET_OBJECT_SIGNAL_INFO
, NULL
,
9101 m_siginfo_data
.get (), 0, TYPE_LENGTH (type
));
9104 /* The inferior can be gone if the user types "print exit(0)"
9105 (and perhaps other times). */
9106 if (target_has_execution ())
9107 /* NB: The register write goes through to the target. */
9108 regcache
->restore (registers ());
9112 /* How the current thread stopped before the inferior function call was
9114 struct thread_suspend_state m_thread_suspend
;
9116 /* The registers before the inferior function call was executed. */
9117 std::unique_ptr
<readonly_detached_regcache
> m_registers
;
9119 /* Format of SIGINFO_DATA or NULL if it is not present. */
9120 struct gdbarch
*m_siginfo_gdbarch
= nullptr;
9122 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
9123 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
9124 content would be invalid. */
9125 gdb::unique_xmalloc_ptr
<gdb_byte
> m_siginfo_data
;
9128 infcall_suspend_state_up
9129 save_infcall_suspend_state ()
9131 struct thread_info
*tp
= inferior_thread ();
9132 struct regcache
*regcache
= get_current_regcache ();
9133 struct gdbarch
*gdbarch
= regcache
->arch ();
9135 infcall_suspend_state_up inf_state
9136 (new struct infcall_suspend_state (gdbarch
, tp
, regcache
));
9138 /* Having saved the current state, adjust the thread state, discarding
9139 any stop signal information. The stop signal is not useful when
9140 starting an inferior function call, and run_inferior_call will not use
9141 the signal due to its `proceed' call with GDB_SIGNAL_0. */
9142 tp
->set_stop_signal (GDB_SIGNAL_0
);
9147 /* Restore inferior session state to INF_STATE. */
9150 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
9152 struct thread_info
*tp
= inferior_thread ();
9153 struct regcache
*regcache
= get_current_regcache ();
9154 struct gdbarch
*gdbarch
= regcache
->arch ();
9156 inf_state
->restore (gdbarch
, tp
, regcache
);
9157 discard_infcall_suspend_state (inf_state
);
9161 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
9166 readonly_detached_regcache
*
9167 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
9169 return inf_state
->registers ();
9172 /* infcall_control_state contains state regarding gdb's control of the
9173 inferior itself like stepping control. It also contains session state like
9174 the user's currently selected frame. */
9176 struct infcall_control_state
9178 struct thread_control_state thread_control
;
9179 struct inferior_control_state inferior_control
;
9182 enum stop_stack_kind stop_stack_dummy
= STOP_NONE
;
9183 int stopped_by_random_signal
= 0;
9185 /* ID and level of the selected frame when the inferior function
9187 struct frame_id selected_frame_id
{};
9188 int selected_frame_level
= -1;
9191 /* Save all of the information associated with the inferior<==>gdb
9194 infcall_control_state_up
9195 save_infcall_control_state ()
9197 infcall_control_state_up
inf_status (new struct infcall_control_state
);
9198 struct thread_info
*tp
= inferior_thread ();
9199 struct inferior
*inf
= current_inferior ();
9201 inf_status
->thread_control
= tp
->control
;
9202 inf_status
->inferior_control
= inf
->control
;
9204 tp
->control
.step_resume_breakpoint
= NULL
;
9205 tp
->control
.exception_resume_breakpoint
= NULL
;
9207 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
9208 chain. If caller's caller is walking the chain, they'll be happier if we
9209 hand them back the original chain when restore_infcall_control_state is
9211 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
9214 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
9215 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
9217 save_selected_frame (&inf_status
->selected_frame_id
,
9218 &inf_status
->selected_frame_level
);
9223 /* Restore inferior session state to INF_STATUS. */
9226 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
9228 struct thread_info
*tp
= inferior_thread ();
9229 struct inferior
*inf
= current_inferior ();
9231 if (tp
->control
.step_resume_breakpoint
)
9232 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
9234 if (tp
->control
.exception_resume_breakpoint
)
9235 tp
->control
.exception_resume_breakpoint
->disposition
9236 = disp_del_at_next_stop
;
9238 /* Handle the bpstat_copy of the chain. */
9239 bpstat_clear (&tp
->control
.stop_bpstat
);
9241 tp
->control
= inf_status
->thread_control
;
9242 inf
->control
= inf_status
->inferior_control
;
9245 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
9246 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
9248 if (target_has_stack ())
9250 restore_selected_frame (inf_status
->selected_frame_id
,
9251 inf_status
->selected_frame_level
);
9258 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
9260 if (inf_status
->thread_control
.step_resume_breakpoint
)
9261 inf_status
->thread_control
.step_resume_breakpoint
->disposition
9262 = disp_del_at_next_stop
;
9264 if (inf_status
->thread_control
.exception_resume_breakpoint
)
9265 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
9266 = disp_del_at_next_stop
;
9268 /* See save_infcall_control_state for info on stop_bpstat. */
9269 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
9277 clear_exit_convenience_vars (void)
9279 clear_internalvar (lookup_internalvar ("_exitsignal"));
9280 clear_internalvar (lookup_internalvar ("_exitcode"));
9284 /* User interface for reverse debugging:
9285 Set exec-direction / show exec-direction commands
9286 (returns error unless target implements to_set_exec_direction method). */
9288 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
9289 static const char exec_forward
[] = "forward";
9290 static const char exec_reverse
[] = "reverse";
9291 static const char *exec_direction
= exec_forward
;
9292 static const char *const exec_direction_names
[] = {
9299 set_exec_direction_func (const char *args
, int from_tty
,
9300 struct cmd_list_element
*cmd
)
9302 if (target_can_execute_reverse ())
9304 if (!strcmp (exec_direction
, exec_forward
))
9305 execution_direction
= EXEC_FORWARD
;
9306 else if (!strcmp (exec_direction
, exec_reverse
))
9307 execution_direction
= EXEC_REVERSE
;
9311 exec_direction
= exec_forward
;
9312 error (_("Target does not support this operation."));
9317 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
9318 struct cmd_list_element
*cmd
, const char *value
)
9320 switch (execution_direction
) {
9322 fprintf_filtered (out
, _("Forward.\n"));
9325 fprintf_filtered (out
, _("Reverse.\n"));
9328 internal_error (__FILE__
, __LINE__
,
9329 _("bogus execution_direction value: %d"),
9330 (int) execution_direction
);
9335 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
9336 struct cmd_list_element
*c
, const char *value
)
9338 fprintf_filtered (file
, _("Resuming the execution of threads "
9339 "of all processes is %s.\n"), value
);
9342 /* Implementation of `siginfo' variable. */
9344 static const struct internalvar_funcs siginfo_funcs
=
9351 /* Callback for infrun's target events source. This is marked when a
9352 thread has a pending status to process. */
9355 infrun_async_inferior_event_handler (gdb_client_data data
)
9357 clear_async_event_handler (infrun_async_inferior_event_token
);
9358 inferior_event_handler (INF_REG_EVENT
);
9365 /* Verify that when two threads with the same ptid exist (from two different
9366 targets) and one of them changes ptid, we only update inferior_ptid if
9367 it is appropriate. */
9370 infrun_thread_ptid_changed ()
9372 gdbarch
*arch
= current_inferior ()->gdbarch
;
9374 /* The thread which inferior_ptid represents changes ptid. */
9376 scoped_restore_current_pspace_and_thread restore
;
9378 scoped_mock_context
<test_target_ops
> target1 (arch
);
9379 scoped_mock_context
<test_target_ops
> target2 (arch
);
9381 ptid_t
old_ptid (111, 222);
9382 ptid_t
new_ptid (111, 333);
9384 target1
.mock_inferior
.pid
= old_ptid
.pid ();
9385 target1
.mock_thread
.ptid
= old_ptid
;
9386 target1
.mock_inferior
.ptid_thread_map
.clear ();
9387 target1
.mock_inferior
.ptid_thread_map
[old_ptid
] = &target1
.mock_thread
;
9389 target2
.mock_inferior
.pid
= old_ptid
.pid ();
9390 target2
.mock_thread
.ptid
= old_ptid
;
9391 target2
.mock_inferior
.ptid_thread_map
.clear ();
9392 target2
.mock_inferior
.ptid_thread_map
[old_ptid
] = &target2
.mock_thread
;
9394 auto restore_inferior_ptid
= make_scoped_restore (&inferior_ptid
, old_ptid
);
9395 set_current_inferior (&target1
.mock_inferior
);
9397 thread_change_ptid (&target1
.mock_target
, old_ptid
, new_ptid
);
9399 gdb_assert (inferior_ptid
== new_ptid
);
9402 /* A thread with the same ptid as inferior_ptid, but from another target,
9405 scoped_restore_current_pspace_and_thread restore
;
9407 scoped_mock_context
<test_target_ops
> target1 (arch
);
9408 scoped_mock_context
<test_target_ops
> target2 (arch
);
9410 ptid_t
old_ptid (111, 222);
9411 ptid_t
new_ptid (111, 333);
9413 target1
.mock_inferior
.pid
= old_ptid
.pid ();
9414 target1
.mock_thread
.ptid
= old_ptid
;
9415 target1
.mock_inferior
.ptid_thread_map
.clear ();
9416 target1
.mock_inferior
.ptid_thread_map
[old_ptid
] = &target1
.mock_thread
;
9418 target2
.mock_inferior
.pid
= old_ptid
.pid ();
9419 target2
.mock_thread
.ptid
= old_ptid
;
9420 target2
.mock_inferior
.ptid_thread_map
.clear ();
9421 target2
.mock_inferior
.ptid_thread_map
[old_ptid
] = &target2
.mock_thread
;
9423 auto restore_inferior_ptid
= make_scoped_restore (&inferior_ptid
, old_ptid
);
9424 set_current_inferior (&target2
.mock_inferior
);
9426 thread_change_ptid (&target1
.mock_target
, old_ptid
, new_ptid
);
9428 gdb_assert (inferior_ptid
== old_ptid
);
9432 } /* namespace selftests */
9434 #endif /* GDB_SELF_TEST */
9436 void _initialize_infrun ();
9438 _initialize_infrun ()
9440 struct cmd_list_element
*c
;
9442 /* Register extra event sources in the event loop. */
9443 infrun_async_inferior_event_token
9444 = create_async_event_handler (infrun_async_inferior_event_handler
, NULL
,
9447 cmd_list_element
*info_signals_cmd
9448 = add_info ("signals", info_signals_command
, _("\
9449 What debugger does when program gets various signals.\n\
9450 Specify a signal as argument to print info on that signal only."));
9451 add_info_alias ("handle", info_signals_cmd
, 0);
9453 c
= add_com ("handle", class_run
, handle_command
, _("\
9454 Specify how to handle signals.\n\
9455 Usage: handle SIGNAL [ACTIONS]\n\
9456 Args are signals and actions to apply to those signals.\n\
9457 If no actions are specified, the current settings for the specified signals\n\
9458 will be displayed instead.\n\
9460 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
9461 from 1-15 are allowed for compatibility with old versions of GDB.\n\
9462 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
9463 The special arg \"all\" is recognized to mean all signals except those\n\
9464 used by the debugger, typically SIGTRAP and SIGINT.\n\
9466 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
9467 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
9468 Stop means reenter debugger if this signal happens (implies print).\n\
9469 Print means print a message if this signal happens.\n\
9470 Pass means let program see this signal; otherwise program doesn't know.\n\
9471 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
9472 Pass and Stop may be combined.\n\
9474 Multiple signals may be specified. Signal numbers and signal names\n\
9475 may be interspersed with actions, with the actions being performed for\n\
9476 all signals cumulatively specified."));
9477 set_cmd_completer (c
, handle_completer
);
9480 stop_command
= add_cmd ("stop", class_obscure
,
9481 not_just_help_class_command
, _("\
9482 There is no `stop' command, but you can set a hook on `stop'.\n\
9483 This allows you to set a list of commands to be run each time execution\n\
9484 of the program stops."), &cmdlist
);
9486 add_setshow_boolean_cmd
9487 ("infrun", class_maintenance
, &debug_infrun
,
9488 _("Set inferior debugging."),
9489 _("Show inferior debugging."),
9490 _("When non-zero, inferior specific debugging is enabled."),
9491 NULL
, show_debug_infrun
, &setdebuglist
, &showdebuglist
);
9493 add_setshow_boolean_cmd ("non-stop", no_class
,
9495 Set whether gdb controls the inferior in non-stop mode."), _("\
9496 Show whether gdb controls the inferior in non-stop mode."), _("\
9497 When debugging a multi-threaded program and this setting is\n\
9498 off (the default, also called all-stop mode), when one thread stops\n\
9499 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9500 all other threads in the program while you interact with the thread of\n\
9501 interest. When you continue or step a thread, you can allow the other\n\
9502 threads to run, or have them remain stopped, but while you inspect any\n\
9503 thread's state, all threads stop.\n\
9505 In non-stop mode, when one thread stops, other threads can continue\n\
9506 to run freely. You'll be able to step each thread independently,\n\
9507 leave it stopped or free to run as needed."),
9513 for (size_t i
= 0; i
< GDB_SIGNAL_LAST
; i
++)
9516 signal_print
[i
] = 1;
9517 signal_program
[i
] = 1;
9518 signal_catch
[i
] = 0;
9521 /* Signals caused by debugger's own actions should not be given to
9522 the program afterwards.
9524 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9525 explicitly specifies that it should be delivered to the target
9526 program. Typically, that would occur when a user is debugging a
9527 target monitor on a simulator: the target monitor sets a
9528 breakpoint; the simulator encounters this breakpoint and halts
9529 the simulation handing control to GDB; GDB, noting that the stop
9530 address doesn't map to any known breakpoint, returns control back
9531 to the simulator; the simulator then delivers the hardware
9532 equivalent of a GDB_SIGNAL_TRAP to the program being
9534 signal_program
[GDB_SIGNAL_TRAP
] = 0;
9535 signal_program
[GDB_SIGNAL_INT
] = 0;
9537 /* Signals that are not errors should not normally enter the debugger. */
9538 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
9539 signal_print
[GDB_SIGNAL_ALRM
] = 0;
9540 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
9541 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
9542 signal_stop
[GDB_SIGNAL_PROF
] = 0;
9543 signal_print
[GDB_SIGNAL_PROF
] = 0;
9544 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
9545 signal_print
[GDB_SIGNAL_CHLD
] = 0;
9546 signal_stop
[GDB_SIGNAL_IO
] = 0;
9547 signal_print
[GDB_SIGNAL_IO
] = 0;
9548 signal_stop
[GDB_SIGNAL_POLL
] = 0;
9549 signal_print
[GDB_SIGNAL_POLL
] = 0;
9550 signal_stop
[GDB_SIGNAL_URG
] = 0;
9551 signal_print
[GDB_SIGNAL_URG
] = 0;
9552 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
9553 signal_print
[GDB_SIGNAL_WINCH
] = 0;
9554 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
9555 signal_print
[GDB_SIGNAL_PRIO
] = 0;
9557 /* These signals are used internally by user-level thread
9558 implementations. (See signal(5) on Solaris.) Like the above
9559 signals, a healthy program receives and handles them as part of
9560 its normal operation. */
9561 signal_stop
[GDB_SIGNAL_LWP
] = 0;
9562 signal_print
[GDB_SIGNAL_LWP
] = 0;
9563 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
9564 signal_print
[GDB_SIGNAL_WAITING
] = 0;
9565 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
9566 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
9567 signal_stop
[GDB_SIGNAL_LIBRT
] = 0;
9568 signal_print
[GDB_SIGNAL_LIBRT
] = 0;
9570 /* Update cached state. */
9571 signal_cache_update (-1);
9573 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
9574 &stop_on_solib_events
, _("\
9575 Set stopping for shared library events."), _("\
9576 Show stopping for shared library events."), _("\
9577 If nonzero, gdb will give control to the user when the dynamic linker\n\
9578 notifies gdb of shared library events. The most common event of interest\n\
9579 to the user would be loading/unloading of a new library."),
9580 set_stop_on_solib_events
,
9581 show_stop_on_solib_events
,
9582 &setlist
, &showlist
);
9584 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
9585 follow_fork_mode_kind_names
,
9586 &follow_fork_mode_string
, _("\
9587 Set debugger response to a program call of fork or vfork."), _("\
9588 Show debugger response to a program call of fork or vfork."), _("\
9589 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9590 parent - the original process is debugged after a fork\n\
9591 child - the new process is debugged after a fork\n\
9592 The unfollowed process will continue to run.\n\
9593 By default, the debugger will follow the parent process."),
9595 show_follow_fork_mode_string
,
9596 &setlist
, &showlist
);
9598 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
9599 follow_exec_mode_names
,
9600 &follow_exec_mode_string
, _("\
9601 Set debugger response to a program call of exec."), _("\
9602 Show debugger response to a program call of exec."), _("\
9603 An exec call replaces the program image of a process.\n\
9605 follow-exec-mode can be:\n\
9607 new - the debugger creates a new inferior and rebinds the process\n\
9608 to this new inferior. The program the process was running before\n\
9609 the exec call can be restarted afterwards by restarting the original\n\
9612 same - the debugger keeps the process bound to the same inferior.\n\
9613 The new executable image replaces the previous executable loaded in\n\
9614 the inferior. Restarting the inferior after the exec call restarts\n\
9615 the executable the process was running after the exec call.\n\
9617 By default, the debugger will use the same inferior."),
9619 show_follow_exec_mode_string
,
9620 &setlist
, &showlist
);
9622 add_setshow_enum_cmd ("scheduler-locking", class_run
,
9623 scheduler_enums
, &scheduler_mode
, _("\
9624 Set mode for locking scheduler during execution."), _("\
9625 Show mode for locking scheduler during execution."), _("\
9626 off == no locking (threads may preempt at any time)\n\
9627 on == full locking (no thread except the current thread may run)\n\
9628 This applies to both normal execution and replay mode.\n\
9629 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9630 In this mode, other threads may run during other commands.\n\
9631 This applies to both normal execution and replay mode.\n\
9632 replay == scheduler locked in replay mode and unlocked during normal execution."),
9633 set_schedlock_func
, /* traps on target vector */
9634 show_scheduler_mode
,
9635 &setlist
, &showlist
);
9637 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
9638 Set mode for resuming threads of all processes."), _("\
9639 Show mode for resuming threads of all processes."), _("\
9640 When on, execution commands (such as 'continue' or 'next') resume all\n\
9641 threads of all processes. When off (which is the default), execution\n\
9642 commands only resume the threads of the current process. The set of\n\
9643 threads that are resumed is further refined by the scheduler-locking\n\
9644 mode (see help set scheduler-locking)."),
9646 show_schedule_multiple
,
9647 &setlist
, &showlist
);
9649 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
9650 Set mode of the step operation."), _("\
9651 Show mode of the step operation."), _("\
9652 When set, doing a step over a function without debug line information\n\
9653 will stop at the first instruction of that function. Otherwise, the\n\
9654 function is skipped and the step command stops at a different source line."),
9656 show_step_stop_if_no_debug
,
9657 &setlist
, &showlist
);
9659 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
9660 &can_use_displaced_stepping
, _("\
9661 Set debugger's willingness to use displaced stepping."), _("\
9662 Show debugger's willingness to use displaced stepping."), _("\
9663 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9664 supported by the target architecture. If off, gdb will not use displaced\n\
9665 stepping to step over breakpoints, even if such is supported by the target\n\
9666 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9667 if the target architecture supports it and non-stop mode is active, but will not\n\
9668 use it in all-stop mode (see help set non-stop)."),
9670 show_can_use_displaced_stepping
,
9671 &setlist
, &showlist
);
9673 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
9674 &exec_direction
, _("Set direction of execution.\n\
9675 Options are 'forward' or 'reverse'."),
9676 _("Show direction of execution (forward/reverse)."),
9677 _("Tells gdb whether to execute forward or backward."),
9678 set_exec_direction_func
, show_exec_direction_func
,
9679 &setlist
, &showlist
);
9681 /* Set/show detach-on-fork: user-settable mode. */
9683 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
9684 Set whether gdb will detach the child of a fork."), _("\
9685 Show whether gdb will detach the child of a fork."), _("\
9686 Tells gdb whether to detach the child of a fork."),
9687 NULL
, NULL
, &setlist
, &showlist
);
9689 /* Set/show disable address space randomization mode. */
9691 add_setshow_boolean_cmd ("disable-randomization", class_support
,
9692 &disable_randomization
, _("\
9693 Set disabling of debuggee's virtual address space randomization."), _("\
9694 Show disabling of debuggee's virtual address space randomization."), _("\
9695 When this mode is on (which is the default), randomization of the virtual\n\
9696 address space is disabled. Standalone programs run with the randomization\n\
9697 enabled by default on some platforms."),
9698 &set_disable_randomization
,
9699 &show_disable_randomization
,
9700 &setlist
, &showlist
);
9702 /* ptid initializations */
9703 inferior_ptid
= null_ptid
;
9704 target_last_wait_ptid
= minus_one_ptid
;
9706 gdb::observers::thread_ptid_changed
.attach (infrun_thread_ptid_changed
,
9708 gdb::observers::thread_stop_requested
.attach (infrun_thread_stop_requested
,
9710 gdb::observers::thread_exit
.attach (infrun_thread_thread_exit
, "infrun");
9711 gdb::observers::inferior_exit
.attach (infrun_inferior_exit
, "infrun");
9712 gdb::observers::inferior_execd
.attach (infrun_inferior_execd
, "infrun");
9714 /* Explicitly create without lookup, since that tries to create a
9715 value with a void typed value, and when we get here, gdbarch
9716 isn't initialized yet. At this point, we're quite sure there
9717 isn't another convenience variable of the same name. */
9718 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
9720 add_setshow_boolean_cmd ("observer", no_class
,
9721 &observer_mode_1
, _("\
9722 Set whether gdb controls the inferior in observer mode."), _("\
9723 Show whether gdb controls the inferior in observer mode."), _("\
9724 In observer mode, GDB can get data from the inferior, but not\n\
9725 affect its execution. Registers and memory may not be changed,\n\
9726 breakpoints may not be set, and the program cannot be interrupted\n\
9734 selftests::register_test ("infrun_thread_ptid_changed",
9735 selftests::infrun_thread_ptid_changed
);