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
, CORE_ADDR pc
);
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
)
408 ptid_t parent_ptid
, child_ptid
;
410 has_vforked
= (inferior_thread ()->pending_follow
.kind
411 == TARGET_WAITKIND_VFORKED
);
412 parent_ptid
= inferior_ptid
;
413 child_ptid
= inferior_thread ()->pending_follow
.value
.related_pid
;
416 && !non_stop
/* Non-stop always resumes both branches. */
417 && current_ui
->prompt_state
== PROMPT_BLOCKED
418 && !(follow_child
|| detach_fork
|| sched_multi
))
420 /* The parent stays blocked inside the vfork syscall until the
421 child execs or exits. If we don't let the child run, then
422 the parent stays blocked. If we're telling the parent to run
423 in the foreground, the user will not be able to ctrl-c to get
424 back the terminal, effectively hanging the debug session. */
425 fprintf_filtered (gdb_stderr
, _("\
426 Can not resume the parent process over vfork in the foreground while\n\
427 holding the child stopped. Try \"set detach-on-fork\" or \
428 \"set schedule-multiple\".\n"));
434 /* Detach new forked process? */
437 /* Before detaching from the child, remove all breakpoints
438 from it. If we forked, then this has already been taken
439 care of by infrun.c. If we vforked however, any
440 breakpoint inserted in the parent is visible in the
441 child, even those added while stopped in a vfork
442 catchpoint. This will remove the breakpoints from the
443 parent also, but they'll be reinserted below. */
446 /* Keep breakpoints list in sync. */
447 remove_breakpoints_inf (current_inferior ());
450 if (print_inferior_events
)
452 /* Ensure that we have a process ptid. */
453 ptid_t process_ptid
= ptid_t (child_ptid
.pid ());
455 target_terminal::ours_for_output ();
456 fprintf_filtered (gdb_stdlog
,
457 _("[Detaching after %s from child %s]\n"),
458 has_vforked
? "vfork" : "fork",
459 target_pid_to_str (process_ptid
).c_str ());
464 struct inferior
*parent_inf
, *child_inf
;
466 /* Add process to GDB's tables. */
467 child_inf
= add_inferior (child_ptid
.pid ());
469 parent_inf
= current_inferior ();
470 child_inf
->attach_flag
= parent_inf
->attach_flag
;
471 copy_terminal_info (child_inf
, parent_inf
);
472 child_inf
->gdbarch
= parent_inf
->gdbarch
;
473 copy_inferior_target_desc_info (child_inf
, parent_inf
);
475 scoped_restore_current_pspace_and_thread restore_pspace_thread
;
477 set_current_inferior (child_inf
);
478 switch_to_no_thread ();
479 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
480 child_inf
->push_target (parent_inf
->process_target ());
481 thread_info
*child_thr
482 = add_thread_silent (child_inf
->process_target (), child_ptid
);
484 /* If this is a vfork child, then the address-space is
485 shared with the parent. */
488 child_inf
->pspace
= parent_inf
->pspace
;
489 child_inf
->aspace
= parent_inf
->aspace
;
493 /* The parent will be frozen until the child is done
494 with the shared region. Keep track of the
496 child_inf
->vfork_parent
= parent_inf
;
497 child_inf
->pending_detach
= 0;
498 parent_inf
->vfork_child
= child_inf
;
499 parent_inf
->pending_detach
= 0;
501 /* Now that the inferiors and program spaces are all
502 wired up, we can switch to the child thread (which
503 switches inferior and program space too). */
504 switch_to_thread (child_thr
);
508 child_inf
->aspace
= new_address_space ();
509 child_inf
->pspace
= new program_space (child_inf
->aspace
);
510 child_inf
->removable
= 1;
511 set_current_program_space (child_inf
->pspace
);
512 clone_program_space (child_inf
->pspace
, parent_inf
->pspace
);
514 /* solib_create_inferior_hook relies on the current
516 switch_to_thread (child_thr
);
518 /* Let the shared library layer (e.g., solib-svr4) learn
519 about this new process, relocate the cloned exec, pull
520 in shared libraries, and install the solib event
521 breakpoint. If a "cloned-VM" event was propagated
522 better throughout the core, this wouldn't be
524 scoped_restore restore_in_initial_library_scan
525 = make_scoped_restore (&child_inf
->in_initial_library_scan
,
527 solib_create_inferior_hook (0);
533 struct inferior
*parent_inf
;
535 parent_inf
= current_inferior ();
537 /* If we detached from the child, then we have to be careful
538 to not insert breakpoints in the parent until the child
539 is done with the shared memory region. However, if we're
540 staying attached to the child, then we can and should
541 insert breakpoints, so that we can debug it. A
542 subsequent child exec or exit is enough to know when does
543 the child stops using the parent's address space. */
544 parent_inf
->waiting_for_vfork_done
= detach_fork
;
545 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
550 /* Follow the child. */
551 struct inferior
*parent_inf
, *child_inf
;
552 struct program_space
*parent_pspace
;
554 if (print_inferior_events
)
556 std::string parent_pid
= target_pid_to_str (parent_ptid
);
557 std::string child_pid
= target_pid_to_str (child_ptid
);
559 target_terminal::ours_for_output ();
560 fprintf_filtered (gdb_stdlog
,
561 _("[Attaching after %s %s to child %s]\n"),
563 has_vforked
? "vfork" : "fork",
567 /* Add the new inferior first, so that the target_detach below
568 doesn't unpush the target. */
570 child_inf
= add_inferior (child_ptid
.pid ());
572 parent_inf
= current_inferior ();
573 child_inf
->attach_flag
= parent_inf
->attach_flag
;
574 copy_terminal_info (child_inf
, parent_inf
);
575 child_inf
->gdbarch
= parent_inf
->gdbarch
;
576 copy_inferior_target_desc_info (child_inf
, parent_inf
);
578 parent_pspace
= parent_inf
->pspace
;
580 process_stratum_target
*target
= parent_inf
->process_target ();
583 /* Hold a strong reference to the target while (maybe)
584 detaching the parent. Otherwise detaching could close the
586 auto target_ref
= target_ops_ref::new_reference (target
);
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 /* Note that the detach above makes PARENT_INF dangling. */
628 /* Add the child thread to the appropriate lists, and switch
629 to this new thread, before cloning the program space, and
630 informing the solib layer about this new process. */
632 set_current_inferior (child_inf
);
633 child_inf
->push_target (target
);
636 thread_info
*child_thr
= add_thread_silent (target
, child_ptid
);
638 /* If this is a vfork child, then the address-space is shared
639 with the parent. If we detached from the parent, then we can
640 reuse the parent's program/address spaces. */
641 if (has_vforked
|| detach_fork
)
643 child_inf
->pspace
= parent_pspace
;
644 child_inf
->aspace
= child_inf
->pspace
->aspace
;
650 child_inf
->aspace
= new_address_space ();
651 child_inf
->pspace
= new program_space (child_inf
->aspace
);
652 child_inf
->removable
= 1;
653 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
654 set_current_program_space (child_inf
->pspace
);
655 clone_program_space (child_inf
->pspace
, parent_pspace
);
657 /* Let the shared library layer (e.g., solib-svr4) learn
658 about this new process, relocate the cloned exec, pull in
659 shared libraries, and install the solib event breakpoint.
660 If a "cloned-VM" event was propagated better throughout
661 the core, this wouldn't be required. */
662 scoped_restore restore_in_initial_library_scan
663 = make_scoped_restore (&child_inf
->in_initial_library_scan
, true);
664 solib_create_inferior_hook (0);
667 switch_to_thread (child_thr
);
670 target_follow_fork (follow_child
, detach_fork
);
675 /* Tell the target to follow the fork we're stopped at. Returns true
676 if the inferior should be resumed; false, if the target for some
677 reason decided it's best not to resume. */
682 bool follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
683 bool should_resume
= true;
684 struct thread_info
*tp
;
686 /* Copy user stepping state to the new inferior thread. FIXME: the
687 followed fork child thread should have a copy of most of the
688 parent thread structure's run control related fields, not just these.
689 Initialized to avoid "may be used uninitialized" warnings from gcc. */
690 struct breakpoint
*step_resume_breakpoint
= NULL
;
691 struct breakpoint
*exception_resume_breakpoint
= NULL
;
692 CORE_ADDR step_range_start
= 0;
693 CORE_ADDR step_range_end
= 0;
694 int current_line
= 0;
695 symtab
*current_symtab
= NULL
;
696 struct frame_id step_frame_id
= { 0 };
697 struct thread_fsm
*thread_fsm
= NULL
;
701 process_stratum_target
*wait_target
;
703 struct target_waitstatus wait_status
;
705 /* Get the last target status returned by target_wait(). */
706 get_last_target_status (&wait_target
, &wait_ptid
, &wait_status
);
708 /* If not stopped at a fork event, then there's nothing else to
710 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
711 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
714 /* Check if we switched over from WAIT_PTID, since the event was
716 if (wait_ptid
!= minus_one_ptid
717 && (current_inferior ()->process_target () != wait_target
718 || inferior_ptid
!= wait_ptid
))
720 /* We did. Switch back to WAIT_PTID thread, to tell the
721 target to follow it (in either direction). We'll
722 afterwards refuse to resume, and inform the user what
724 thread_info
*wait_thread
= find_thread_ptid (wait_target
, wait_ptid
);
725 switch_to_thread (wait_thread
);
726 should_resume
= false;
730 tp
= inferior_thread ();
732 /* If there were any forks/vforks that were caught and are now to be
733 followed, then do so now. */
734 switch (tp
->pending_follow
.kind
)
736 case TARGET_WAITKIND_FORKED
:
737 case TARGET_WAITKIND_VFORKED
:
739 ptid_t parent
, child
;
741 /* If the user did a next/step, etc, over a fork call,
742 preserve the stepping state in the fork child. */
743 if (follow_child
&& should_resume
)
745 step_resume_breakpoint
= clone_momentary_breakpoint
746 (tp
->control
.step_resume_breakpoint
);
747 step_range_start
= tp
->control
.step_range_start
;
748 step_range_end
= tp
->control
.step_range_end
;
749 current_line
= tp
->current_line
;
750 current_symtab
= tp
->current_symtab
;
751 step_frame_id
= tp
->control
.step_frame_id
;
752 exception_resume_breakpoint
753 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
754 thread_fsm
= tp
->thread_fsm
;
756 /* For now, delete the parent's sr breakpoint, otherwise,
757 parent/child sr breakpoints are considered duplicates,
758 and the child version will not be installed. Remove
759 this when the breakpoints module becomes aware of
760 inferiors and address spaces. */
761 delete_step_resume_breakpoint (tp
);
762 tp
->control
.step_range_start
= 0;
763 tp
->control
.step_range_end
= 0;
764 tp
->control
.step_frame_id
= null_frame_id
;
765 delete_exception_resume_breakpoint (tp
);
766 tp
->thread_fsm
= NULL
;
769 parent
= inferior_ptid
;
770 child
= tp
->pending_follow
.value
.related_pid
;
772 process_stratum_target
*parent_targ
= tp
->inf
->process_target ();
773 /* Set up inferior(s) as specified by the caller, and tell the
774 target to do whatever is necessary to follow either parent
776 if (follow_fork_inferior (follow_child
, detach_fork
))
778 /* Target refused to follow, or there's some other reason
779 we shouldn't resume. */
784 /* This pending follow fork event is now handled, one way
785 or another. The previous selected thread may be gone
786 from the lists by now, but if it is still around, need
787 to clear the pending follow request. */
788 tp
= find_thread_ptid (parent_targ
, parent
);
790 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
792 /* This makes sure we don't try to apply the "Switched
793 over from WAIT_PID" logic above. */
794 nullify_last_target_wait_ptid ();
796 /* If we followed the child, switch to it... */
799 thread_info
*child_thr
= find_thread_ptid (parent_targ
, child
);
800 switch_to_thread (child_thr
);
802 /* ... and preserve the stepping state, in case the
803 user was stepping over the fork call. */
806 tp
= inferior_thread ();
807 tp
->control
.step_resume_breakpoint
808 = step_resume_breakpoint
;
809 tp
->control
.step_range_start
= step_range_start
;
810 tp
->control
.step_range_end
= step_range_end
;
811 tp
->current_line
= current_line
;
812 tp
->current_symtab
= current_symtab
;
813 tp
->control
.step_frame_id
= step_frame_id
;
814 tp
->control
.exception_resume_breakpoint
815 = exception_resume_breakpoint
;
816 tp
->thread_fsm
= thread_fsm
;
820 /* If we get here, it was because we're trying to
821 resume from a fork catchpoint, but, the user
822 has switched threads away from the thread that
823 forked. In that case, the resume command
824 issued is most likely not applicable to the
825 child, so just warn, and refuse to resume. */
826 warning (_("Not resuming: switched threads "
827 "before following fork child."));
830 /* Reset breakpoints in the child as appropriate. */
831 follow_inferior_reset_breakpoints ();
836 case TARGET_WAITKIND_SPURIOUS
:
837 /* Nothing to follow. */
840 internal_error (__FILE__
, __LINE__
,
841 "Unexpected pending_follow.kind %d\n",
842 tp
->pending_follow
.kind
);
846 return should_resume
;
850 follow_inferior_reset_breakpoints (void)
852 struct thread_info
*tp
= inferior_thread ();
854 /* Was there a step_resume breakpoint? (There was if the user
855 did a "next" at the fork() call.) If so, explicitly reset its
856 thread number. Cloned step_resume breakpoints are disabled on
857 creation, so enable it here now that it is associated with the
860 step_resumes are a form of bp that are made to be per-thread.
861 Since we created the step_resume bp when the parent process
862 was being debugged, and now are switching to the child process,
863 from the breakpoint package's viewpoint, that's a switch of
864 "threads". We must update the bp's notion of which thread
865 it is for, or it'll be ignored when it triggers. */
867 if (tp
->control
.step_resume_breakpoint
)
869 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
870 tp
->control
.step_resume_breakpoint
->loc
->enabled
= 1;
873 /* Treat exception_resume breakpoints like step_resume breakpoints. */
874 if (tp
->control
.exception_resume_breakpoint
)
876 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
877 tp
->control
.exception_resume_breakpoint
->loc
->enabled
= 1;
880 /* Reinsert all breakpoints in the child. The user may have set
881 breakpoints after catching the fork, in which case those
882 were never set in the child, but only in the parent. This makes
883 sure the inserted breakpoints match the breakpoint list. */
885 breakpoint_re_set ();
886 insert_breakpoints ();
889 /* The child has exited or execed: resume threads of the parent the
890 user wanted to be executing. */
893 proceed_after_vfork_done (struct thread_info
*thread
,
896 int pid
= * (int *) arg
;
898 if (thread
->ptid
.pid () == pid
899 && thread
->state
== THREAD_RUNNING
900 && !thread
->executing
901 && !thread
->stop_requested
902 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
904 infrun_debug_printf ("resuming vfork parent thread %s",
905 target_pid_to_str (thread
->ptid
).c_str ());
907 switch_to_thread (thread
);
908 clear_proceed_status (0);
909 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
);
915 /* Called whenever we notice an exec or exit event, to handle
916 detaching or resuming a vfork parent. */
919 handle_vfork_child_exec_or_exit (int exec
)
921 struct inferior
*inf
= current_inferior ();
923 if (inf
->vfork_parent
)
925 int resume_parent
= -1;
927 /* This exec or exit marks the end of the shared memory region
928 between the parent and the child. Break the bonds. */
929 inferior
*vfork_parent
= inf
->vfork_parent
;
930 inf
->vfork_parent
->vfork_child
= NULL
;
931 inf
->vfork_parent
= NULL
;
933 /* If the user wanted to detach from the parent, now is the
935 if (vfork_parent
->pending_detach
)
937 struct program_space
*pspace
;
938 struct address_space
*aspace
;
940 /* follow-fork child, detach-on-fork on. */
942 vfork_parent
->pending_detach
= 0;
944 scoped_restore_current_pspace_and_thread restore_thread
;
946 /* We're letting loose of the parent. */
947 thread_info
*tp
= any_live_thread_of_inferior (vfork_parent
);
948 switch_to_thread (tp
);
950 /* We're about to detach from the parent, which implicitly
951 removes breakpoints from its address space. There's a
952 catch here: we want to reuse the spaces for the child,
953 but, parent/child are still sharing the pspace at this
954 point, although the exec in reality makes the kernel give
955 the child a fresh set of new pages. The problem here is
956 that the breakpoints module being unaware of this, would
957 likely chose the child process to write to the parent
958 address space. Swapping the child temporarily away from
959 the spaces has the desired effect. Yes, this is "sort
962 pspace
= inf
->pspace
;
963 aspace
= inf
->aspace
;
967 if (print_inferior_events
)
970 = target_pid_to_str (ptid_t (vfork_parent
->pid
));
972 target_terminal::ours_for_output ();
976 fprintf_filtered (gdb_stdlog
,
977 _("[Detaching vfork parent %s "
978 "after child exec]\n"), pidstr
.c_str ());
982 fprintf_filtered (gdb_stdlog
,
983 _("[Detaching vfork parent %s "
984 "after child exit]\n"), pidstr
.c_str ());
988 target_detach (vfork_parent
, 0);
991 inf
->pspace
= pspace
;
992 inf
->aspace
= aspace
;
996 /* We're staying attached to the parent, so, really give the
997 child a new address space. */
998 inf
->pspace
= new program_space (maybe_new_address_space ());
999 inf
->aspace
= inf
->pspace
->aspace
;
1001 set_current_program_space (inf
->pspace
);
1003 resume_parent
= vfork_parent
->pid
;
1007 /* If this is a vfork child exiting, then the pspace and
1008 aspaces were shared with the parent. Since we're
1009 reporting the process exit, we'll be mourning all that is
1010 found in the address space, and switching to null_ptid,
1011 preparing to start a new inferior. But, since we don't
1012 want to clobber the parent's address/program spaces, we
1013 go ahead and create a new one for this exiting
1016 /* Switch to no-thread while running clone_program_space, so
1017 that clone_program_space doesn't want to read the
1018 selected frame of a dead process. */
1019 scoped_restore_current_thread restore_thread
;
1020 switch_to_no_thread ();
1022 inf
->pspace
= new program_space (maybe_new_address_space ());
1023 inf
->aspace
= inf
->pspace
->aspace
;
1024 set_current_program_space (inf
->pspace
);
1026 inf
->symfile_flags
= SYMFILE_NO_READ
;
1027 clone_program_space (inf
->pspace
, vfork_parent
->pspace
);
1029 resume_parent
= vfork_parent
->pid
;
1032 gdb_assert (current_program_space
== inf
->pspace
);
1034 if (non_stop
&& resume_parent
!= -1)
1036 /* If the user wanted the parent to be running, let it go
1038 scoped_restore_current_thread restore_thread
;
1040 infrun_debug_printf ("resuming vfork parent process %d",
1043 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
1048 /* Enum strings for "set|show follow-exec-mode". */
1050 static const char follow_exec_mode_new
[] = "new";
1051 static const char follow_exec_mode_same
[] = "same";
1052 static const char *const follow_exec_mode_names
[] =
1054 follow_exec_mode_new
,
1055 follow_exec_mode_same
,
1059 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1061 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1062 struct cmd_list_element
*c
, const char *value
)
1064 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1067 /* EXEC_FILE_TARGET is assumed to be non-NULL. */
1070 follow_exec (ptid_t ptid
, const char *exec_file_target
)
1072 int pid
= ptid
.pid ();
1073 ptid_t process_ptid
;
1075 /* Switch terminal for any messages produced e.g. by
1076 breakpoint_re_set. */
1077 target_terminal::ours_for_output ();
1079 /* This is an exec event that we actually wish to pay attention to.
1080 Refresh our symbol table to the newly exec'd program, remove any
1081 momentary bp's, etc.
1083 If there are breakpoints, they aren't really inserted now,
1084 since the exec() transformed our inferior into a fresh set
1087 We want to preserve symbolic breakpoints on the list, since
1088 we have hopes that they can be reset after the new a.out's
1089 symbol table is read.
1091 However, any "raw" breakpoints must be removed from the list
1092 (e.g., the solib bp's), since their address is probably invalid
1095 And, we DON'T want to call delete_breakpoints() here, since
1096 that may write the bp's "shadow contents" (the instruction
1097 value that was overwritten with a TRAP instruction). Since
1098 we now have a new a.out, those shadow contents aren't valid. */
1100 mark_breakpoints_out ();
1102 /* The target reports the exec event to the main thread, even if
1103 some other thread does the exec, and even if the main thread was
1104 stopped or already gone. We may still have non-leader threads of
1105 the process on our list. E.g., on targets that don't have thread
1106 exit events (like remote); or on native Linux in non-stop mode if
1107 there were only two threads in the inferior and the non-leader
1108 one is the one that execs (and nothing forces an update of the
1109 thread list up to here). When debugging remotely, it's best to
1110 avoid extra traffic, when possible, so avoid syncing the thread
1111 list with the target, and instead go ahead and delete all threads
1112 of the process but one that reported the event. Note this must
1113 be done before calling update_breakpoints_after_exec, as
1114 otherwise clearing the threads' resources would reference stale
1115 thread breakpoints -- it may have been one of these threads that
1116 stepped across the exec. We could just clear their stepping
1117 states, but as long as we're iterating, might as well delete
1118 them. Deleting them now rather than at the next user-visible
1119 stop provides a nicer sequence of events for user and MI
1121 for (thread_info
*th
: all_threads_safe ())
1122 if (th
->ptid
.pid () == pid
&& th
->ptid
!= ptid
)
1125 /* We also need to clear any left over stale state for the
1126 leader/event thread. E.g., if there was any step-resume
1127 breakpoint or similar, it's gone now. We cannot truly
1128 step-to-next statement through an exec(). */
1129 thread_info
*th
= inferior_thread ();
1130 th
->control
.step_resume_breakpoint
= NULL
;
1131 th
->control
.exception_resume_breakpoint
= NULL
;
1132 th
->control
.single_step_breakpoints
= NULL
;
1133 th
->control
.step_range_start
= 0;
1134 th
->control
.step_range_end
= 0;
1136 /* The user may have had the main thread held stopped in the
1137 previous image (e.g., schedlock on, or non-stop). Release
1139 th
->stop_requested
= 0;
1141 update_breakpoints_after_exec ();
1143 /* What is this a.out's name? */
1144 process_ptid
= ptid_t (pid
);
1145 printf_unfiltered (_("%s is executing new program: %s\n"),
1146 target_pid_to_str (process_ptid
).c_str (),
1149 /* We've followed the inferior through an exec. Therefore, the
1150 inferior has essentially been killed & reborn. */
1152 breakpoint_init_inferior (inf_execd
);
1154 gdb::unique_xmalloc_ptr
<char> exec_file_host
1155 = exec_file_find (exec_file_target
, NULL
);
1157 /* If we were unable to map the executable target pathname onto a host
1158 pathname, tell the user that. Otherwise GDB's subsequent behavior
1159 is confusing. Maybe it would even be better to stop at this point
1160 so that the user can specify a file manually before continuing. */
1161 if (exec_file_host
== NULL
)
1162 warning (_("Could not load symbols for executable %s.\n"
1163 "Do you need \"set sysroot\"?"),
1166 /* Reset the shared library package. This ensures that we get a
1167 shlib event when the child reaches "_start", at which point the
1168 dld will have had a chance to initialize the child. */
1169 /* Also, loading a symbol file below may trigger symbol lookups, and
1170 we don't want those to be satisfied by the libraries of the
1171 previous incarnation of this process. */
1172 no_shared_libraries (NULL
, 0);
1174 struct inferior
*inf
= current_inferior ();
1176 if (follow_exec_mode_string
== follow_exec_mode_new
)
1178 /* The user wants to keep the old inferior and program spaces
1179 around. Create a new fresh one, and switch to it. */
1181 /* Do exit processing for the original inferior before setting the new
1182 inferior's pid. Having two inferiors with the same pid would confuse
1183 find_inferior_p(t)id. Transfer the terminal state and info from the
1184 old to the new inferior. */
1185 inferior
*new_inferior
= add_inferior_with_spaces ();
1187 swap_terminal_info (new_inferior
, inf
);
1188 exit_inferior_silent (inf
);
1190 new_inferior
->pid
= pid
;
1191 target_follow_exec (new_inferior
, ptid
, exec_file_target
);
1193 /* We continue with the new inferior. */
1198 /* The old description may no longer be fit for the new image.
1199 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1200 old description; we'll read a new one below. No need to do
1201 this on "follow-exec-mode new", as the old inferior stays
1202 around (its description is later cleared/refetched on
1204 target_clear_description ();
1205 target_follow_exec (inf
, ptid
, exec_file_target
);
1208 gdb_assert (current_inferior () == inf
);
1209 gdb_assert (current_program_space
== inf
->pspace
);
1211 /* Attempt to open the exec file. SYMFILE_DEFER_BP_RESET is used
1212 because the proper displacement for a PIE (Position Independent
1213 Executable) main symbol file will only be computed by
1214 solib_create_inferior_hook below. breakpoint_re_set would fail
1215 to insert the breakpoints with the zero displacement. */
1216 try_open_exec_file (exec_file_host
.get (), inf
, SYMFILE_DEFER_BP_RESET
);
1218 /* If the target can specify a description, read it. Must do this
1219 after flipping to the new executable (because the target supplied
1220 description must be compatible with the executable's
1221 architecture, and the old executable may e.g., be 32-bit, while
1222 the new one 64-bit), and before anything involving memory or
1224 target_find_description ();
1226 gdb::observers::inferior_execd
.notify (inf
);
1228 breakpoint_re_set ();
1230 /* Reinsert all breakpoints. (Those which were symbolic have
1231 been reset to the proper address in the new a.out, thanks
1232 to symbol_file_command...). */
1233 insert_breakpoints ();
1235 /* The next resume of this inferior should bring it to the shlib
1236 startup breakpoints. (If the user had also set bp's on
1237 "main" from the old (parent) process, then they'll auto-
1238 matically get reset there in the new process.). */
1241 /* The chain of threads that need to do a step-over operation to get
1242 past e.g., a breakpoint. What technique is used to step over the
1243 breakpoint/watchpoint does not matter -- all threads end up in the
1244 same queue, to maintain rough temporal order of execution, in order
1245 to avoid starvation, otherwise, we could e.g., find ourselves
1246 constantly stepping the same couple threads past their breakpoints
1247 over and over, if the single-step finish fast enough. */
1248 struct thread_info
*global_thread_step_over_chain_head
;
1250 /* Bit flags indicating what the thread needs to step over. */
1252 enum step_over_what_flag
1254 /* Step over a breakpoint. */
1255 STEP_OVER_BREAKPOINT
= 1,
1257 /* Step past a non-continuable watchpoint, in order to let the
1258 instruction execute so we can evaluate the watchpoint
1260 STEP_OVER_WATCHPOINT
= 2
1262 DEF_ENUM_FLAGS_TYPE (enum step_over_what_flag
, step_over_what
);
1264 /* Info about an instruction that is being stepped over. */
1266 struct step_over_info
1268 /* If we're stepping past a breakpoint, this is the address space
1269 and address of the instruction the breakpoint is set at. We'll
1270 skip inserting all breakpoints here. Valid iff ASPACE is
1272 const address_space
*aspace
= nullptr;
1273 CORE_ADDR address
= 0;
1275 /* The instruction being stepped over triggers a nonsteppable
1276 watchpoint. If true, we'll skip inserting watchpoints. */
1277 int nonsteppable_watchpoint_p
= 0;
1279 /* The thread's global number. */
1283 /* The step-over info of the location that is being stepped over.
1285 Note that with async/breakpoint always-inserted mode, a user might
1286 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1287 being stepped over. As setting a new breakpoint inserts all
1288 breakpoints, we need to make sure the breakpoint being stepped over
1289 isn't inserted then. We do that by only clearing the step-over
1290 info when the step-over is actually finished (or aborted).
1292 Presently GDB can only step over one breakpoint at any given time.
1293 Given threads that can't run code in the same address space as the
1294 breakpoint's can't really miss the breakpoint, GDB could be taught
1295 to step-over at most one breakpoint per address space (so this info
1296 could move to the address space object if/when GDB is extended).
1297 The set of breakpoints being stepped over will normally be much
1298 smaller than the set of all breakpoints, so a flag in the
1299 breakpoint location structure would be wasteful. A separate list
1300 also saves complexity and run-time, as otherwise we'd have to go
1301 through all breakpoint locations clearing their flag whenever we
1302 start a new sequence. Similar considerations weigh against storing
1303 this info in the thread object. Plus, not all step overs actually
1304 have breakpoint locations -- e.g., stepping past a single-step
1305 breakpoint, or stepping to complete a non-continuable
1307 static struct step_over_info step_over_info
;
1309 /* Record the address of the breakpoint/instruction we're currently
1311 N.B. We record the aspace and address now, instead of say just the thread,
1312 because when we need the info later the thread may be running. */
1315 set_step_over_info (const address_space
*aspace
, CORE_ADDR address
,
1316 int nonsteppable_watchpoint_p
,
1319 step_over_info
.aspace
= aspace
;
1320 step_over_info
.address
= address
;
1321 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1322 step_over_info
.thread
= thread
;
1325 /* Called when we're not longer stepping over a breakpoint / an
1326 instruction, so all breakpoints are free to be (re)inserted. */
1329 clear_step_over_info (void)
1331 infrun_debug_printf ("clearing step over info");
1332 step_over_info
.aspace
= NULL
;
1333 step_over_info
.address
= 0;
1334 step_over_info
.nonsteppable_watchpoint_p
= 0;
1335 step_over_info
.thread
= -1;
1341 stepping_past_instruction_at (struct address_space
*aspace
,
1344 return (step_over_info
.aspace
!= NULL
1345 && breakpoint_address_match (aspace
, address
,
1346 step_over_info
.aspace
,
1347 step_over_info
.address
));
1353 thread_is_stepping_over_breakpoint (int thread
)
1355 return (step_over_info
.thread
!= -1
1356 && thread
== step_over_info
.thread
);
1362 stepping_past_nonsteppable_watchpoint (void)
1364 return step_over_info
.nonsteppable_watchpoint_p
;
1367 /* Returns true if step-over info is valid. */
1370 step_over_info_valid_p (void)
1372 return (step_over_info
.aspace
!= NULL
1373 || stepping_past_nonsteppable_watchpoint ());
1377 /* Displaced stepping. */
1379 /* In non-stop debugging mode, we must take special care to manage
1380 breakpoints properly; in particular, the traditional strategy for
1381 stepping a thread past a breakpoint it has hit is unsuitable.
1382 'Displaced stepping' is a tactic for stepping one thread past a
1383 breakpoint it has hit while ensuring that other threads running
1384 concurrently will hit the breakpoint as they should.
1386 The traditional way to step a thread T off a breakpoint in a
1387 multi-threaded program in all-stop mode is as follows:
1389 a0) Initially, all threads are stopped, and breakpoints are not
1391 a1) We single-step T, leaving breakpoints uninserted.
1392 a2) We insert breakpoints, and resume all threads.
1394 In non-stop debugging, however, this strategy is unsuitable: we
1395 don't want to have to stop all threads in the system in order to
1396 continue or step T past a breakpoint. Instead, we use displaced
1399 n0) Initially, T is stopped, other threads are running, and
1400 breakpoints are inserted.
1401 n1) We copy the instruction "under" the breakpoint to a separate
1402 location, outside the main code stream, making any adjustments
1403 to the instruction, register, and memory state as directed by
1405 n2) We single-step T over the instruction at its new location.
1406 n3) We adjust the resulting register and memory state as directed
1407 by T's architecture. This includes resetting T's PC to point
1408 back into the main instruction stream.
1411 This approach depends on the following gdbarch methods:
1413 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1414 indicate where to copy the instruction, and how much space must
1415 be reserved there. We use these in step n1.
1417 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1418 address, and makes any necessary adjustments to the instruction,
1419 register contents, and memory. We use this in step n1.
1421 - gdbarch_displaced_step_fixup adjusts registers and memory after
1422 we have successfully single-stepped the instruction, to yield the
1423 same effect the instruction would have had if we had executed it
1424 at its original address. We use this in step n3.
1426 The gdbarch_displaced_step_copy_insn and
1427 gdbarch_displaced_step_fixup functions must be written so that
1428 copying an instruction with gdbarch_displaced_step_copy_insn,
1429 single-stepping across the copied instruction, and then applying
1430 gdbarch_displaced_insn_fixup should have the same effects on the
1431 thread's memory and registers as stepping the instruction in place
1432 would have. Exactly which responsibilities fall to the copy and
1433 which fall to the fixup is up to the author of those functions.
1435 See the comments in gdbarch.sh for details.
1437 Note that displaced stepping and software single-step cannot
1438 currently be used in combination, although with some care I think
1439 they could be made to. Software single-step works by placing
1440 breakpoints on all possible subsequent instructions; if the
1441 displaced instruction is a PC-relative jump, those breakpoints
1442 could fall in very strange places --- on pages that aren't
1443 executable, or at addresses that are not proper instruction
1444 boundaries. (We do generally let other threads run while we wait
1445 to hit the software single-step breakpoint, and they might
1446 encounter such a corrupted instruction.) One way to work around
1447 this would be to have gdbarch_displaced_step_copy_insn fully
1448 simulate the effect of PC-relative instructions (and return NULL)
1449 on architectures that use software single-stepping.
1451 In non-stop mode, we can have independent and simultaneous step
1452 requests, so more than one thread may need to simultaneously step
1453 over a breakpoint. The current implementation assumes there is
1454 only one scratch space per process. In this case, we have to
1455 serialize access to the scratch space. If thread A wants to step
1456 over a breakpoint, but we are currently waiting for some other
1457 thread to complete a displaced step, we leave thread A stopped and
1458 place it in the displaced_step_request_queue. Whenever a displaced
1459 step finishes, we pick the next thread in the queue and start a new
1460 displaced step operation on it. See displaced_step_prepare and
1461 displaced_step_finish for details. */
1463 /* Return true if THREAD is doing a displaced step. */
1466 displaced_step_in_progress_thread (thread_info
*thread
)
1468 gdb_assert (thread
!= NULL
);
1470 return thread
->displaced_step_state
.in_progress ();
1473 /* Return true if INF has a thread doing a displaced step. */
1476 displaced_step_in_progress (inferior
*inf
)
1478 return inf
->displaced_step_state
.in_progress_count
> 0;
1481 /* Return true if any thread is doing a displaced step. */
1484 displaced_step_in_progress_any_thread ()
1486 for (inferior
*inf
: all_non_exited_inferiors ())
1488 if (displaced_step_in_progress (inf
))
1496 infrun_inferior_exit (struct inferior
*inf
)
1498 inf
->displaced_step_state
.reset ();
1502 infrun_inferior_execd (inferior
*inf
)
1504 /* If some threads where was doing a displaced step in this inferior at the
1505 moment of the exec, they no longer exist. Even if the exec'ing thread
1506 doing a displaced step, we don't want to to any fixup nor restore displaced
1507 stepping buffer bytes. */
1508 inf
->displaced_step_state
.reset ();
1510 for (thread_info
*thread
: inf
->threads ())
1511 thread
->displaced_step_state
.reset ();
1513 /* Since an in-line step is done with everything else stopped, if there was
1514 one in progress at the time of the exec, it must have been the exec'ing
1516 clear_step_over_info ();
1519 /* If ON, and the architecture supports it, GDB will use displaced
1520 stepping to step over breakpoints. If OFF, or if the architecture
1521 doesn't support it, GDB will instead use the traditional
1522 hold-and-step approach. If AUTO (which is the default), GDB will
1523 decide which technique to use to step over breakpoints depending on
1524 whether the target works in a non-stop way (see use_displaced_stepping). */
1526 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1529 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1530 struct cmd_list_element
*c
,
1533 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1534 fprintf_filtered (file
,
1535 _("Debugger's willingness to use displaced stepping "
1536 "to step over breakpoints is %s (currently %s).\n"),
1537 value
, target_is_non_stop_p () ? "on" : "off");
1539 fprintf_filtered (file
,
1540 _("Debugger's willingness to use displaced stepping "
1541 "to step over breakpoints is %s.\n"), value
);
1544 /* Return true if the gdbarch implements the required methods to use
1545 displaced stepping. */
1548 gdbarch_supports_displaced_stepping (gdbarch
*arch
)
1550 /* Only check for the presence of `prepare`. The gdbarch verification ensures
1551 that if `prepare` is provided, so is `finish`. */
1552 return gdbarch_displaced_step_prepare_p (arch
);
1555 /* Return non-zero if displaced stepping can/should be used to step
1556 over breakpoints of thread TP. */
1559 use_displaced_stepping (thread_info
*tp
)
1561 /* If the user disabled it explicitly, don't use displaced stepping. */
1562 if (can_use_displaced_stepping
== AUTO_BOOLEAN_FALSE
)
1565 /* If "auto", only use displaced stepping if the target operates in a non-stop
1567 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
1568 && !target_is_non_stop_p ())
1571 gdbarch
*gdbarch
= get_thread_regcache (tp
)->arch ();
1573 /* If the architecture doesn't implement displaced stepping, don't use
1575 if (!gdbarch_supports_displaced_stepping (gdbarch
))
1578 /* If recording, don't use displaced stepping. */
1579 if (find_record_target () != nullptr)
1582 /* If displaced stepping failed before for this inferior, don't bother trying
1584 if (tp
->inf
->displaced_step_state
.failed_before
)
1590 /* Simple function wrapper around displaced_step_thread_state::reset. */
1593 displaced_step_reset (displaced_step_thread_state
*displaced
)
1595 displaced
->reset ();
1598 /* A cleanup that wraps displaced_step_reset. We use this instead of, say,
1599 SCOPE_EXIT, because it needs to be discardable with "cleanup.release ()". */
1601 using displaced_step_reset_cleanup
= FORWARD_SCOPE_EXIT (displaced_step_reset
);
1606 displaced_step_dump_bytes (const gdb_byte
*buf
, size_t len
)
1610 for (size_t i
= 0; i
< len
; i
++)
1613 ret
+= string_printf ("%02x", buf
[i
]);
1615 ret
+= string_printf (" %02x", buf
[i
]);
1621 /* Prepare to single-step, using displaced stepping.
1623 Note that we cannot use displaced stepping when we have a signal to
1624 deliver. If we have a signal to deliver and an instruction to step
1625 over, then after the step, there will be no indication from the
1626 target whether the thread entered a signal handler or ignored the
1627 signal and stepped over the instruction successfully --- both cases
1628 result in a simple SIGTRAP. In the first case we mustn't do a
1629 fixup, and in the second case we must --- but we can't tell which.
1630 Comments in the code for 'random signals' in handle_inferior_event
1631 explain how we handle this case instead.
1633 Returns DISPLACED_STEP_PREPARE_STATUS_OK if preparing was successful -- this
1634 thread is going to be stepped now; DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE
1635 if displaced stepping this thread got queued; or
1636 DISPLACED_STEP_PREPARE_STATUS_CANT if this instruction can't be displaced
1639 static displaced_step_prepare_status
1640 displaced_step_prepare_throw (thread_info
*tp
)
1642 regcache
*regcache
= get_thread_regcache (tp
);
1643 struct gdbarch
*gdbarch
= regcache
->arch ();
1644 displaced_step_thread_state
&disp_step_thread_state
1645 = tp
->displaced_step_state
;
1647 /* We should never reach this function if the architecture does not
1648 support displaced stepping. */
1649 gdb_assert (gdbarch_supports_displaced_stepping (gdbarch
));
1651 /* Nor if the thread isn't meant to step over a breakpoint. */
1652 gdb_assert (tp
->control
.trap_expected
);
1654 /* Disable range stepping while executing in the scratch pad. We
1655 want a single-step even if executing the displaced instruction in
1656 the scratch buffer lands within the stepping range (e.g., a
1658 tp
->control
.may_range_step
= 0;
1660 /* We are about to start a displaced step for this thread. If one is already
1661 in progress, something's wrong. */
1662 gdb_assert (!disp_step_thread_state
.in_progress ());
1664 if (tp
->inf
->displaced_step_state
.unavailable
)
1666 /* The gdbarch tells us it's not worth asking to try a prepare because
1667 it is likely that it will return unavailable, so don't bother asking. */
1669 displaced_debug_printf ("deferring step of %s",
1670 target_pid_to_str (tp
->ptid
).c_str ());
1672 global_thread_step_over_chain_enqueue (tp
);
1673 return DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE
;
1676 displaced_debug_printf ("displaced-stepping %s now",
1677 target_pid_to_str (tp
->ptid
).c_str ());
1679 scoped_restore_current_thread restore_thread
;
1681 switch_to_thread (tp
);
1683 CORE_ADDR original_pc
= regcache_read_pc (regcache
);
1684 CORE_ADDR displaced_pc
;
1686 displaced_step_prepare_status status
1687 = gdbarch_displaced_step_prepare (gdbarch
, tp
, displaced_pc
);
1689 if (status
== DISPLACED_STEP_PREPARE_STATUS_CANT
)
1691 displaced_debug_printf ("failed to prepare (%s)",
1692 target_pid_to_str (tp
->ptid
).c_str ());
1694 return DISPLACED_STEP_PREPARE_STATUS_CANT
;
1696 else if (status
== DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE
)
1698 /* Not enough displaced stepping resources available, defer this
1699 request by placing it the queue. */
1701 displaced_debug_printf ("not enough resources available, "
1702 "deferring step of %s",
1703 target_pid_to_str (tp
->ptid
).c_str ());
1705 global_thread_step_over_chain_enqueue (tp
);
1707 return DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE
;
1710 gdb_assert (status
== DISPLACED_STEP_PREPARE_STATUS_OK
);
1712 /* Save the information we need to fix things up if the step
1714 disp_step_thread_state
.set (gdbarch
);
1716 tp
->inf
->displaced_step_state
.in_progress_count
++;
1718 displaced_debug_printf ("prepared successfully thread=%s, "
1719 "original_pc=%s, displaced_pc=%s",
1720 target_pid_to_str (tp
->ptid
).c_str (),
1721 paddress (gdbarch
, original_pc
),
1722 paddress (gdbarch
, displaced_pc
));
1724 return DISPLACED_STEP_PREPARE_STATUS_OK
;
1727 /* Wrapper for displaced_step_prepare_throw that disabled further
1728 attempts at displaced stepping if we get a memory error. */
1730 static displaced_step_prepare_status
1731 displaced_step_prepare (thread_info
*thread
)
1733 displaced_step_prepare_status status
1734 = DISPLACED_STEP_PREPARE_STATUS_CANT
;
1738 status
= displaced_step_prepare_throw (thread
);
1740 catch (const gdb_exception_error
&ex
)
1742 if (ex
.error
!= MEMORY_ERROR
1743 && ex
.error
!= NOT_SUPPORTED_ERROR
)
1746 infrun_debug_printf ("caught exception, disabling displaced stepping: %s",
1749 /* Be verbose if "set displaced-stepping" is "on", silent if
1751 if (can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1753 warning (_("disabling displaced stepping: %s"),
1757 /* Disable further displaced stepping attempts. */
1758 thread
->inf
->displaced_step_state
.failed_before
= 1;
1764 /* If we displaced stepped an instruction successfully, adjust registers and
1765 memory to yield the same effect the instruction would have had if we had
1766 executed it at its original address, and return
1767 DISPLACED_STEP_FINISH_STATUS_OK. If the instruction didn't complete,
1768 relocate the PC and return DISPLACED_STEP_FINISH_STATUS_NOT_EXECUTED.
1770 If the thread wasn't displaced stepping, return
1771 DISPLACED_STEP_FINISH_STATUS_OK as well. */
1773 static displaced_step_finish_status
1774 displaced_step_finish (thread_info
*event_thread
, enum gdb_signal signal
)
1776 displaced_step_thread_state
*displaced
= &event_thread
->displaced_step_state
;
1778 /* Was this thread performing a displaced step? */
1779 if (!displaced
->in_progress ())
1780 return DISPLACED_STEP_FINISH_STATUS_OK
;
1782 gdb_assert (event_thread
->inf
->displaced_step_state
.in_progress_count
> 0);
1783 event_thread
->inf
->displaced_step_state
.in_progress_count
--;
1785 /* Fixup may need to read memory/registers. Switch to the thread
1786 that we're fixing up. Also, target_stopped_by_watchpoint checks
1787 the current thread, and displaced_step_restore performs ptid-dependent
1788 memory accesses using current_inferior(). */
1789 switch_to_thread (event_thread
);
1791 displaced_step_reset_cleanup
cleanup (displaced
);
1793 /* Do the fixup, and release the resources acquired to do the displaced
1795 return gdbarch_displaced_step_finish (displaced
->get_original_gdbarch (),
1796 event_thread
, signal
);
1799 /* Data to be passed around while handling an event. This data is
1800 discarded between events. */
1801 struct execution_control_state
1803 process_stratum_target
*target
;
1805 /* The thread that got the event, if this was a thread event; NULL
1807 struct thread_info
*event_thread
;
1809 struct target_waitstatus ws
;
1810 int stop_func_filled_in
;
1811 CORE_ADDR stop_func_start
;
1812 CORE_ADDR stop_func_end
;
1813 const char *stop_func_name
;
1816 /* True if the event thread hit the single-step breakpoint of
1817 another thread. Thus the event doesn't cause a stop, the thread
1818 needs to be single-stepped past the single-step breakpoint before
1819 we can switch back to the original stepping thread. */
1820 int hit_singlestep_breakpoint
;
1823 /* Clear ECS and set it to point at TP. */
1826 reset_ecs (struct execution_control_state
*ecs
, struct thread_info
*tp
)
1828 memset (ecs
, 0, sizeof (*ecs
));
1829 ecs
->event_thread
= tp
;
1830 ecs
->ptid
= tp
->ptid
;
1833 static void keep_going_pass_signal (struct execution_control_state
*ecs
);
1834 static void prepare_to_wait (struct execution_control_state
*ecs
);
1835 static bool keep_going_stepped_thread (struct thread_info
*tp
);
1836 static step_over_what
thread_still_needs_step_over (struct thread_info
*tp
);
1838 /* Are there any pending step-over requests? If so, run all we can
1839 now and return true. Otherwise, return false. */
1842 start_step_over (void)
1844 INFRUN_SCOPED_DEBUG_ENTER_EXIT
;
1848 /* Don't start a new step-over if we already have an in-line
1849 step-over operation ongoing. */
1850 if (step_over_info_valid_p ())
1853 /* Steal the global thread step over chain. As we try to initiate displaced
1854 steps, threads will be enqueued in the global chain if no buffers are
1855 available. If we iterated on the global chain directly, we might iterate
1857 thread_info
*threads_to_step
= global_thread_step_over_chain_head
;
1858 global_thread_step_over_chain_head
= NULL
;
1860 infrun_debug_printf ("stealing global queue of threads to step, length = %d",
1861 thread_step_over_chain_length (threads_to_step
));
1863 bool started
= false;
1865 /* On scope exit (whatever the reason, return or exception), if there are
1866 threads left in the THREADS_TO_STEP chain, put back these threads in the
1870 if (threads_to_step
== nullptr)
1871 infrun_debug_printf ("step-over queue now empty");
1874 infrun_debug_printf ("putting back %d threads to step in global queue",
1875 thread_step_over_chain_length (threads_to_step
));
1877 global_thread_step_over_chain_enqueue_chain (threads_to_step
);
1881 for (thread_info
*tp
= threads_to_step
; tp
!= NULL
; tp
= next
)
1883 struct execution_control_state ecss
;
1884 struct execution_control_state
*ecs
= &ecss
;
1885 step_over_what step_what
;
1886 int must_be_in_line
;
1888 gdb_assert (!tp
->stop_requested
);
1890 next
= thread_step_over_chain_next (threads_to_step
, tp
);
1892 if (tp
->inf
->displaced_step_state
.unavailable
)
1894 /* The arch told us to not even try preparing another displaced step
1895 for this inferior. Just leave the thread in THREADS_TO_STEP, it
1896 will get moved to the global chain on scope exit. */
1900 /* Remove thread from the THREADS_TO_STEP chain. If anything goes wrong
1901 while we try to prepare the displaced step, we don't add it back to
1902 the global step over chain. This is to avoid a thread staying in the
1903 step over chain indefinitely if something goes wrong when resuming it
1904 If the error is intermittent and it still needs a step over, it will
1905 get enqueued again when we try to resume it normally. */
1906 thread_step_over_chain_remove (&threads_to_step
, tp
);
1908 step_what
= thread_still_needs_step_over (tp
);
1909 must_be_in_line
= ((step_what
& STEP_OVER_WATCHPOINT
)
1910 || ((step_what
& STEP_OVER_BREAKPOINT
)
1911 && !use_displaced_stepping (tp
)));
1913 /* We currently stop all threads of all processes to step-over
1914 in-line. If we need to start a new in-line step-over, let
1915 any pending displaced steps finish first. */
1916 if (must_be_in_line
&& displaced_step_in_progress_any_thread ())
1918 global_thread_step_over_chain_enqueue (tp
);
1922 if (tp
->control
.trap_expected
1926 internal_error (__FILE__
, __LINE__
,
1927 "[%s] has inconsistent state: "
1928 "trap_expected=%d, resumed=%d, executing=%d\n",
1929 target_pid_to_str (tp
->ptid
).c_str (),
1930 tp
->control
.trap_expected
,
1935 infrun_debug_printf ("resuming [%s] for step-over",
1936 target_pid_to_str (tp
->ptid
).c_str ());
1938 /* keep_going_pass_signal skips the step-over if the breakpoint
1939 is no longer inserted. In all-stop, we want to keep looking
1940 for a thread that needs a step-over instead of resuming TP,
1941 because we wouldn't be able to resume anything else until the
1942 target stops again. In non-stop, the resume always resumes
1943 only TP, so it's OK to let the thread resume freely. */
1944 if (!target_is_non_stop_p () && !step_what
)
1947 switch_to_thread (tp
);
1948 reset_ecs (ecs
, tp
);
1949 keep_going_pass_signal (ecs
);
1951 if (!ecs
->wait_some_more
)
1952 error (_("Command aborted."));
1954 /* If the thread's step over could not be initiated because no buffers
1955 were available, it was re-added to the global step over chain. */
1958 infrun_debug_printf ("[%s] was resumed.",
1959 target_pid_to_str (tp
->ptid
).c_str ());
1960 gdb_assert (!thread_is_in_step_over_chain (tp
));
1964 infrun_debug_printf ("[%s] was NOT resumed.",
1965 target_pid_to_str (tp
->ptid
).c_str ());
1966 gdb_assert (thread_is_in_step_over_chain (tp
));
1969 /* If we started a new in-line step-over, we're done. */
1970 if (step_over_info_valid_p ())
1972 gdb_assert (tp
->control
.trap_expected
);
1977 if (!target_is_non_stop_p ())
1979 /* On all-stop, shouldn't have resumed unless we needed a
1981 gdb_assert (tp
->control
.trap_expected
1982 || tp
->step_after_step_resume_breakpoint
);
1984 /* With remote targets (at least), in all-stop, we can't
1985 issue any further remote commands until the program stops
1991 /* Either the thread no longer needed a step-over, or a new
1992 displaced stepping sequence started. Even in the latter
1993 case, continue looking. Maybe we can also start another
1994 displaced step on a thread of other process. */
2000 /* Update global variables holding ptids to hold NEW_PTID if they were
2001 holding OLD_PTID. */
2003 infrun_thread_ptid_changed (process_stratum_target
*target
,
2004 ptid_t old_ptid
, ptid_t new_ptid
)
2006 if (inferior_ptid
== old_ptid
2007 && current_inferior ()->process_target () == target
)
2008 inferior_ptid
= new_ptid
;
2013 static const char schedlock_off
[] = "off";
2014 static const char schedlock_on
[] = "on";
2015 static const char schedlock_step
[] = "step";
2016 static const char schedlock_replay
[] = "replay";
2017 static const char *const scheduler_enums
[] = {
2024 static const char *scheduler_mode
= schedlock_replay
;
2026 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
2027 struct cmd_list_element
*c
, const char *value
)
2029 fprintf_filtered (file
,
2030 _("Mode for locking scheduler "
2031 "during execution is \"%s\".\n"),
2036 set_schedlock_func (const char *args
, int from_tty
, struct cmd_list_element
*c
)
2038 if (!target_can_lock_scheduler ())
2040 scheduler_mode
= schedlock_off
;
2041 error (_("Target '%s' cannot support this command."),
2042 target_shortname ());
2046 /* True if execution commands resume all threads of all processes by
2047 default; otherwise, resume only threads of the current inferior
2049 bool sched_multi
= false;
2051 /* Try to setup for software single stepping over the specified location.
2052 Return true if target_resume() should use hardware single step.
2054 GDBARCH the current gdbarch.
2055 PC the location to step over. */
2058 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
2060 bool hw_step
= true;
2062 if (execution_direction
== EXEC_FORWARD
2063 && gdbarch_software_single_step_p (gdbarch
))
2064 hw_step
= !insert_single_step_breakpoints (gdbarch
);
2072 user_visible_resume_ptid (int step
)
2078 /* With non-stop mode on, threads are always handled
2080 resume_ptid
= inferior_ptid
;
2082 else if ((scheduler_mode
== schedlock_on
)
2083 || (scheduler_mode
== schedlock_step
&& step
))
2085 /* User-settable 'scheduler' mode requires solo thread
2087 resume_ptid
= inferior_ptid
;
2089 else if ((scheduler_mode
== schedlock_replay
)
2090 && target_record_will_replay (minus_one_ptid
, execution_direction
))
2092 /* User-settable 'scheduler' mode requires solo thread resume in replay
2094 resume_ptid
= inferior_ptid
;
2096 else if (!sched_multi
&& target_supports_multi_process ())
2098 /* Resume all threads of the current process (and none of other
2100 resume_ptid
= ptid_t (inferior_ptid
.pid ());
2104 /* Resume all threads of all processes. */
2105 resume_ptid
= RESUME_ALL
;
2113 process_stratum_target
*
2114 user_visible_resume_target (ptid_t resume_ptid
)
2116 return (resume_ptid
== minus_one_ptid
&& sched_multi
2118 : current_inferior ()->process_target ());
2121 /* Return a ptid representing the set of threads that we will resume,
2122 in the perspective of the target, assuming run control handling
2123 does not require leaving some threads stopped (e.g., stepping past
2124 breakpoint). USER_STEP indicates whether we're about to start the
2125 target for a stepping command. */
2128 internal_resume_ptid (int user_step
)
2130 /* In non-stop, we always control threads individually. Note that
2131 the target may always work in non-stop mode even with "set
2132 non-stop off", in which case user_visible_resume_ptid could
2133 return a wildcard ptid. */
2134 if (target_is_non_stop_p ())
2135 return inferior_ptid
;
2137 return user_visible_resume_ptid (user_step
);
2140 /* Wrapper for target_resume, that handles infrun-specific
2144 do_target_resume (ptid_t resume_ptid
, bool step
, enum gdb_signal sig
)
2146 struct thread_info
*tp
= inferior_thread ();
2148 gdb_assert (!tp
->stop_requested
);
2150 /* Install inferior's terminal modes. */
2151 target_terminal::inferior ();
2153 /* Avoid confusing the next resume, if the next stop/resume
2154 happens to apply to another thread. */
2155 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2157 /* Advise target which signals may be handled silently.
2159 If we have removed breakpoints because we are stepping over one
2160 in-line (in any thread), we need to receive all signals to avoid
2161 accidentally skipping a breakpoint during execution of a signal
2164 Likewise if we're displaced stepping, otherwise a trap for a
2165 breakpoint in a signal handler might be confused with the
2166 displaced step finishing. We don't make the displaced_step_finish
2167 step distinguish the cases instead, because:
2169 - a backtrace while stopped in the signal handler would show the
2170 scratch pad as frame older than the signal handler, instead of
2171 the real mainline code.
2173 - when the thread is later resumed, the signal handler would
2174 return to the scratch pad area, which would no longer be
2176 if (step_over_info_valid_p ()
2177 || displaced_step_in_progress (tp
->inf
))
2178 target_pass_signals ({});
2180 target_pass_signals (signal_pass
);
2182 target_resume (resume_ptid
, step
, sig
);
2184 if (target_can_async_p ())
2188 /* Resume the inferior. SIG is the signal to give the inferior
2189 (GDB_SIGNAL_0 for none). Note: don't call this directly; instead
2190 call 'resume', which handles exceptions. */
2193 resume_1 (enum gdb_signal sig
)
2195 struct regcache
*regcache
= get_current_regcache ();
2196 struct gdbarch
*gdbarch
= regcache
->arch ();
2197 struct thread_info
*tp
= inferior_thread ();
2198 const address_space
*aspace
= regcache
->aspace ();
2200 /* This represents the user's step vs continue request. When
2201 deciding whether "set scheduler-locking step" applies, it's the
2202 user's intention that counts. */
2203 const int user_step
= tp
->control
.stepping_command
;
2204 /* This represents what we'll actually request the target to do.
2205 This can decay from a step to a continue, if e.g., we need to
2206 implement single-stepping with breakpoints (software
2210 gdb_assert (!tp
->stop_requested
);
2211 gdb_assert (!thread_is_in_step_over_chain (tp
));
2213 if (tp
->suspend
.waitstatus_pending_p
)
2216 ("thread %s has pending wait "
2217 "status %s (currently_stepping=%d).",
2218 target_pid_to_str (tp
->ptid
).c_str (),
2219 target_waitstatus_to_string (&tp
->suspend
.waitstatus
).c_str (),
2220 currently_stepping (tp
));
2222 tp
->inf
->process_target ()->threads_executing
= true;
2225 /* FIXME: What should we do if we are supposed to resume this
2226 thread with a signal? Maybe we should maintain a queue of
2227 pending signals to deliver. */
2228 if (sig
!= GDB_SIGNAL_0
)
2230 warning (_("Couldn't deliver signal %s to %s."),
2231 gdb_signal_to_name (sig
),
2232 target_pid_to_str (tp
->ptid
).c_str ());
2235 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2237 if (target_can_async_p ())
2240 /* Tell the event loop we have an event to process. */
2241 mark_async_event_handler (infrun_async_inferior_event_token
);
2246 tp
->stepped_breakpoint
= 0;
2248 /* Depends on stepped_breakpoint. */
2249 step
= currently_stepping (tp
);
2251 if (current_inferior ()->waiting_for_vfork_done
)
2253 /* Don't try to single-step a vfork parent that is waiting for
2254 the child to get out of the shared memory region (by exec'ing
2255 or exiting). This is particularly important on software
2256 single-step archs, as the child process would trip on the
2257 software single step breakpoint inserted for the parent
2258 process. Since the parent will not actually execute any
2259 instruction until the child is out of the shared region (such
2260 are vfork's semantics), it is safe to simply continue it.
2261 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2262 the parent, and tell it to `keep_going', which automatically
2263 re-sets it stepping. */
2264 infrun_debug_printf ("resume : clear step");
2268 CORE_ADDR pc
= regcache_read_pc (regcache
);
2270 infrun_debug_printf ("step=%d, signal=%s, trap_expected=%d, "
2271 "current thread [%s] at %s",
2272 step
, gdb_signal_to_symbol_string (sig
),
2273 tp
->control
.trap_expected
,
2274 target_pid_to_str (inferior_ptid
).c_str (),
2275 paddress (gdbarch
, pc
));
2277 /* Normally, by the time we reach `resume', the breakpoints are either
2278 removed or inserted, as appropriate. The exception is if we're sitting
2279 at a permanent breakpoint; we need to step over it, but permanent
2280 breakpoints can't be removed. So we have to test for it here. */
2281 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2283 if (sig
!= GDB_SIGNAL_0
)
2285 /* We have a signal to pass to the inferior. The resume
2286 may, or may not take us to the signal handler. If this
2287 is a step, we'll need to stop in the signal handler, if
2288 there's one, (if the target supports stepping into
2289 handlers), or in the next mainline instruction, if
2290 there's no handler. If this is a continue, we need to be
2291 sure to run the handler with all breakpoints inserted.
2292 In all cases, set a breakpoint at the current address
2293 (where the handler returns to), and once that breakpoint
2294 is hit, resume skipping the permanent breakpoint. If
2295 that breakpoint isn't hit, then we've stepped into the
2296 signal handler (or hit some other event). We'll delete
2297 the step-resume breakpoint then. */
2299 infrun_debug_printf ("resume: skipping permanent breakpoint, "
2300 "deliver signal first");
2302 clear_step_over_info ();
2303 tp
->control
.trap_expected
= 0;
2305 if (tp
->control
.step_resume_breakpoint
== NULL
)
2307 /* Set a "high-priority" step-resume, as we don't want
2308 user breakpoints at PC to trigger (again) when this
2310 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2311 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2313 tp
->step_after_step_resume_breakpoint
= step
;
2316 insert_breakpoints ();
2320 /* There's no signal to pass, we can go ahead and skip the
2321 permanent breakpoint manually. */
2322 infrun_debug_printf ("skipping permanent breakpoint");
2323 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2324 /* Update pc to reflect the new address from which we will
2325 execute instructions. */
2326 pc
= regcache_read_pc (regcache
);
2330 /* We've already advanced the PC, so the stepping part
2331 is done. Now we need to arrange for a trap to be
2332 reported to handle_inferior_event. Set a breakpoint
2333 at the current PC, and run to it. Don't update
2334 prev_pc, because if we end in
2335 switch_back_to_stepped_thread, we want the "expected
2336 thread advanced also" branch to be taken. IOW, we
2337 don't want this thread to step further from PC
2339 gdb_assert (!step_over_info_valid_p ());
2340 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2341 insert_breakpoints ();
2343 resume_ptid
= internal_resume_ptid (user_step
);
2344 do_target_resume (resume_ptid
, false, GDB_SIGNAL_0
);
2351 /* If we have a breakpoint to step over, make sure to do a single
2352 step only. Same if we have software watchpoints. */
2353 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2354 tp
->control
.may_range_step
= 0;
2356 /* If displaced stepping is enabled, step over breakpoints by executing a
2357 copy of the instruction at a different address.
2359 We can't use displaced stepping when we have a signal to deliver;
2360 the comments for displaced_step_prepare explain why. The
2361 comments in the handle_inferior event for dealing with 'random
2362 signals' explain what we do instead.
2364 We can't use displaced stepping when we are waiting for vfork_done
2365 event, displaced stepping breaks the vfork child similarly as single
2366 step software breakpoint. */
2367 if (tp
->control
.trap_expected
2368 && use_displaced_stepping (tp
)
2369 && !step_over_info_valid_p ()
2370 && sig
== GDB_SIGNAL_0
2371 && !current_inferior ()->waiting_for_vfork_done
)
2373 displaced_step_prepare_status prepare_status
2374 = displaced_step_prepare (tp
);
2376 if (prepare_status
== DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE
)
2378 infrun_debug_printf ("Got placed in step-over queue");
2380 tp
->control
.trap_expected
= 0;
2383 else if (prepare_status
== DISPLACED_STEP_PREPARE_STATUS_CANT
)
2385 /* Fallback to stepping over the breakpoint in-line. */
2387 if (target_is_non_stop_p ())
2388 stop_all_threads ();
2390 set_step_over_info (regcache
->aspace (),
2391 regcache_read_pc (regcache
), 0, tp
->global_num
);
2393 step
= maybe_software_singlestep (gdbarch
, pc
);
2395 insert_breakpoints ();
2397 else if (prepare_status
== DISPLACED_STEP_PREPARE_STATUS_OK
)
2399 /* Update pc to reflect the new address from which we will
2400 execute instructions due to displaced stepping. */
2401 pc
= regcache_read_pc (get_thread_regcache (tp
));
2403 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
);
2406 gdb_assert_not_reached (_("Invalid displaced_step_prepare_status "
2410 /* Do we need to do it the hard way, w/temp breakpoints? */
2412 step
= maybe_software_singlestep (gdbarch
, pc
);
2414 /* Currently, our software single-step implementation leads to different
2415 results than hardware single-stepping in one situation: when stepping
2416 into delivering a signal which has an associated signal handler,
2417 hardware single-step will stop at the first instruction of the handler,
2418 while software single-step will simply skip execution of the handler.
2420 For now, this difference in behavior is accepted since there is no
2421 easy way to actually implement single-stepping into a signal handler
2422 without kernel support.
2424 However, there is one scenario where this difference leads to follow-on
2425 problems: if we're stepping off a breakpoint by removing all breakpoints
2426 and then single-stepping. In this case, the software single-step
2427 behavior means that even if there is a *breakpoint* in the signal
2428 handler, GDB still would not stop.
2430 Fortunately, we can at least fix this particular issue. We detect
2431 here the case where we are about to deliver a signal while software
2432 single-stepping with breakpoints removed. In this situation, we
2433 revert the decisions to remove all breakpoints and insert single-
2434 step breakpoints, and instead we install a step-resume breakpoint
2435 at the current address, deliver the signal without stepping, and
2436 once we arrive back at the step-resume breakpoint, actually step
2437 over the breakpoint we originally wanted to step over. */
2438 if (thread_has_single_step_breakpoints_set (tp
)
2439 && sig
!= GDB_SIGNAL_0
2440 && step_over_info_valid_p ())
2442 /* If we have nested signals or a pending signal is delivered
2443 immediately after a handler returns, might already have
2444 a step-resume breakpoint set on the earlier handler. We cannot
2445 set another step-resume breakpoint; just continue on until the
2446 original breakpoint is hit. */
2447 if (tp
->control
.step_resume_breakpoint
== NULL
)
2449 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2450 tp
->step_after_step_resume_breakpoint
= 1;
2453 delete_single_step_breakpoints (tp
);
2455 clear_step_over_info ();
2456 tp
->control
.trap_expected
= 0;
2458 insert_breakpoints ();
2461 /* If STEP is set, it's a request to use hardware stepping
2462 facilities. But in that case, we should never
2463 use singlestep breakpoint. */
2464 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2466 /* Decide the set of threads to ask the target to resume. */
2467 if (tp
->control
.trap_expected
)
2469 /* We're allowing a thread to run past a breakpoint it has
2470 hit, either by single-stepping the thread with the breakpoint
2471 removed, or by displaced stepping, with the breakpoint inserted.
2472 In the former case, we need to single-step only this thread,
2473 and keep others stopped, as they can miss this breakpoint if
2474 allowed to run. That's not really a problem for displaced
2475 stepping, but, we still keep other threads stopped, in case
2476 another thread is also stopped for a breakpoint waiting for
2477 its turn in the displaced stepping queue. */
2478 resume_ptid
= inferior_ptid
;
2481 resume_ptid
= internal_resume_ptid (user_step
);
2483 if (execution_direction
!= EXEC_REVERSE
2484 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2486 /* There are two cases where we currently need to step a
2487 breakpoint instruction when we have a signal to deliver:
2489 - See handle_signal_stop where we handle random signals that
2490 could take out us out of the stepping range. Normally, in
2491 that case we end up continuing (instead of stepping) over the
2492 signal handler with a breakpoint at PC, but there are cases
2493 where we should _always_ single-step, even if we have a
2494 step-resume breakpoint, like when a software watchpoint is
2495 set. Assuming single-stepping and delivering a signal at the
2496 same time would takes us to the signal handler, then we could
2497 have removed the breakpoint at PC to step over it. However,
2498 some hardware step targets (like e.g., Mac OS) can't step
2499 into signal handlers, and for those, we need to leave the
2500 breakpoint at PC inserted, as otherwise if the handler
2501 recurses and executes PC again, it'll miss the breakpoint.
2502 So we leave the breakpoint inserted anyway, but we need to
2503 record that we tried to step a breakpoint instruction, so
2504 that adjust_pc_after_break doesn't end up confused.
2506 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2507 in one thread after another thread that was stepping had been
2508 momentarily paused for a step-over. When we re-resume the
2509 stepping thread, it may be resumed from that address with a
2510 breakpoint that hasn't trapped yet. Seen with
2511 gdb.threads/non-stop-fair-events.exp, on targets that don't
2512 do displaced stepping. */
2514 infrun_debug_printf ("resume: [%s] stepped breakpoint",
2515 target_pid_to_str (tp
->ptid
).c_str ());
2517 tp
->stepped_breakpoint
= 1;
2519 /* Most targets can step a breakpoint instruction, thus
2520 executing it normally. But if this one cannot, just
2521 continue and we will hit it anyway. */
2522 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2527 && tp
->control
.trap_expected
2528 && use_displaced_stepping (tp
)
2529 && !step_over_info_valid_p ())
2531 struct regcache
*resume_regcache
= get_thread_regcache (tp
);
2532 struct gdbarch
*resume_gdbarch
= resume_regcache
->arch ();
2533 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2536 read_memory (actual_pc
, buf
, sizeof (buf
));
2537 displaced_debug_printf ("run %s: %s",
2538 paddress (resume_gdbarch
, actual_pc
),
2539 displaced_step_dump_bytes
2540 (buf
, sizeof (buf
)).c_str ());
2543 if (tp
->control
.may_range_step
)
2545 /* If we're resuming a thread with the PC out of the step
2546 range, then we're doing some nested/finer run control
2547 operation, like stepping the thread out of the dynamic
2548 linker or the displaced stepping scratch pad. We
2549 shouldn't have allowed a range step then. */
2550 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2553 do_target_resume (resume_ptid
, step
, sig
);
2557 /* Resume the inferior. SIG is the signal to give the inferior
2558 (GDB_SIGNAL_0 for none). This is a wrapper around 'resume_1' that
2559 rolls back state on error. */
2562 resume (gdb_signal sig
)
2568 catch (const gdb_exception
&ex
)
2570 /* If resuming is being aborted for any reason, delete any
2571 single-step breakpoint resume_1 may have created, to avoid
2572 confusing the following resumption, and to avoid leaving
2573 single-step breakpoints perturbing other threads, in case
2574 we're running in non-stop mode. */
2575 if (inferior_ptid
!= null_ptid
)
2576 delete_single_step_breakpoints (inferior_thread ());
2586 /* Counter that tracks number of user visible stops. This can be used
2587 to tell whether a command has proceeded the inferior past the
2588 current location. This allows e.g., inferior function calls in
2589 breakpoint commands to not interrupt the command list. When the
2590 call finishes successfully, the inferior is standing at the same
2591 breakpoint as if nothing happened (and so we don't call
2593 static ULONGEST current_stop_id
;
2600 return current_stop_id
;
2603 /* Called when we report a user visible stop. */
2611 /* Clear out all variables saying what to do when inferior is continued.
2612 First do this, then set the ones you want, then call `proceed'. */
2615 clear_proceed_status_thread (struct thread_info
*tp
)
2617 infrun_debug_printf ("%s", target_pid_to_str (tp
->ptid
).c_str ());
2619 /* If we're starting a new sequence, then the previous finished
2620 single-step is no longer relevant. */
2621 if (tp
->suspend
.waitstatus_pending_p
)
2623 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
2625 infrun_debug_printf ("pending event of %s was a finished step. "
2627 target_pid_to_str (tp
->ptid
).c_str ());
2629 tp
->suspend
.waitstatus_pending_p
= 0;
2630 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2635 ("thread %s has pending wait status %s (currently_stepping=%d).",
2636 target_pid_to_str (tp
->ptid
).c_str (),
2637 target_waitstatus_to_string (&tp
->suspend
.waitstatus
).c_str (),
2638 currently_stepping (tp
));
2642 /* If this signal should not be seen by program, give it zero.
2643 Used for debugging signals. */
2644 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2645 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2647 delete tp
->thread_fsm
;
2648 tp
->thread_fsm
= NULL
;
2650 tp
->control
.trap_expected
= 0;
2651 tp
->control
.step_range_start
= 0;
2652 tp
->control
.step_range_end
= 0;
2653 tp
->control
.may_range_step
= 0;
2654 tp
->control
.step_frame_id
= null_frame_id
;
2655 tp
->control
.step_stack_frame_id
= null_frame_id
;
2656 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2657 tp
->control
.step_start_function
= NULL
;
2658 tp
->stop_requested
= 0;
2660 tp
->control
.stop_step
= 0;
2662 tp
->control
.proceed_to_finish
= 0;
2664 tp
->control
.stepping_command
= 0;
2666 /* Discard any remaining commands or status from previous stop. */
2667 bpstat_clear (&tp
->control
.stop_bpstat
);
2671 clear_proceed_status (int step
)
2673 /* With scheduler-locking replay, stop replaying other threads if we're
2674 not replaying the user-visible resume ptid.
2676 This is a convenience feature to not require the user to explicitly
2677 stop replaying the other threads. We're assuming that the user's
2678 intent is to resume tracing the recorded process. */
2679 if (!non_stop
&& scheduler_mode
== schedlock_replay
2680 && target_record_is_replaying (minus_one_ptid
)
2681 && !target_record_will_replay (user_visible_resume_ptid (step
),
2682 execution_direction
))
2683 target_record_stop_replaying ();
2685 if (!non_stop
&& inferior_ptid
!= null_ptid
)
2687 ptid_t resume_ptid
= user_visible_resume_ptid (step
);
2688 process_stratum_target
*resume_target
2689 = user_visible_resume_target (resume_ptid
);
2691 /* In all-stop mode, delete the per-thread status of all threads
2692 we're about to resume, implicitly and explicitly. */
2693 for (thread_info
*tp
: all_non_exited_threads (resume_target
, resume_ptid
))
2694 clear_proceed_status_thread (tp
);
2697 if (inferior_ptid
!= null_ptid
)
2699 struct inferior
*inferior
;
2703 /* If in non-stop mode, only delete the per-thread status of
2704 the current thread. */
2705 clear_proceed_status_thread (inferior_thread ());
2708 inferior
= current_inferior ();
2709 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2712 gdb::observers::about_to_proceed
.notify ();
2715 /* Returns true if TP is still stopped at a breakpoint that needs
2716 stepping-over in order to make progress. If the breakpoint is gone
2717 meanwhile, we can skip the whole step-over dance. */
2720 thread_still_needs_step_over_bp (struct thread_info
*tp
)
2722 if (tp
->stepping_over_breakpoint
)
2724 struct regcache
*regcache
= get_thread_regcache (tp
);
2726 if (breakpoint_here_p (regcache
->aspace (),
2727 regcache_read_pc (regcache
))
2728 == ordinary_breakpoint_here
)
2731 tp
->stepping_over_breakpoint
= 0;
2737 /* Check whether thread TP still needs to start a step-over in order
2738 to make progress when resumed. Returns an bitwise or of enum
2739 step_over_what bits, indicating what needs to be stepped over. */
2741 static step_over_what
2742 thread_still_needs_step_over (struct thread_info
*tp
)
2744 step_over_what what
= 0;
2746 if (thread_still_needs_step_over_bp (tp
))
2747 what
|= STEP_OVER_BREAKPOINT
;
2749 if (tp
->stepping_over_watchpoint
2750 && !target_have_steppable_watchpoint ())
2751 what
|= STEP_OVER_WATCHPOINT
;
2756 /* Returns true if scheduler locking applies. STEP indicates whether
2757 we're about to do a step/next-like command to a thread. */
2760 schedlock_applies (struct thread_info
*tp
)
2762 return (scheduler_mode
== schedlock_on
2763 || (scheduler_mode
== schedlock_step
2764 && tp
->control
.stepping_command
)
2765 || (scheduler_mode
== schedlock_replay
2766 && target_record_will_replay (minus_one_ptid
,
2767 execution_direction
)));
2770 /* Set process_stratum_target::COMMIT_RESUMED_STATE in all target
2771 stacks that have threads executing and don't have threads with
2775 maybe_set_commit_resumed_all_targets ()
2777 scoped_restore_current_thread restore_thread
;
2779 for (inferior
*inf
: all_non_exited_inferiors ())
2781 process_stratum_target
*proc_target
= inf
->process_target ();
2783 if (proc_target
->commit_resumed_state
)
2785 /* We already set this in a previous iteration, via another
2786 inferior sharing the process_stratum target. */
2790 /* If the target has no resumed threads, it would be useless to
2791 ask it to commit the resumed threads. */
2792 if (!proc_target
->threads_executing
)
2794 infrun_debug_printf ("not requesting commit-resumed for target "
2795 "%s, no resumed threads",
2796 proc_target
->shortname ());
2800 /* As an optimization, if a thread from this target has some
2801 status to report, handle it before requiring the target to
2802 commit its resumed threads: handling the status might lead to
2803 resuming more threads. */
2804 bool has_thread_with_pending_status
= false;
2805 for (thread_info
*thread
: all_non_exited_threads (proc_target
))
2806 if (thread
->resumed
&& thread
->suspend
.waitstatus_pending_p
)
2808 has_thread_with_pending_status
= true;
2812 if (has_thread_with_pending_status
)
2814 infrun_debug_printf ("not requesting commit-resumed for target %s, a"
2815 " thread has a pending waitstatus",
2816 proc_target
->shortname ());
2820 switch_to_inferior_no_thread (inf
);
2822 if (target_has_pending_events ())
2824 infrun_debug_printf ("not requesting commit-resumed for target %s, "
2825 "target has pending events",
2826 proc_target
->shortname ());
2830 infrun_debug_printf ("enabling commit-resumed for target %s",
2831 proc_target
->shortname ());
2833 proc_target
->commit_resumed_state
= true;
2840 maybe_call_commit_resumed_all_targets ()
2842 scoped_restore_current_thread restore_thread
;
2844 for (inferior
*inf
: all_non_exited_inferiors ())
2846 process_stratum_target
*proc_target
= inf
->process_target ();
2848 if (!proc_target
->commit_resumed_state
)
2851 switch_to_inferior_no_thread (inf
);
2853 infrun_debug_printf ("calling commit_resumed for target %s",
2854 proc_target
->shortname());
2856 target_commit_resumed ();
2860 /* To track nesting of scoped_disable_commit_resumed objects, ensuring
2861 that only the outermost one attempts to re-enable
2863 static bool enable_commit_resumed
= true;
2867 scoped_disable_commit_resumed::scoped_disable_commit_resumed
2868 (const char *reason
)
2869 : m_reason (reason
),
2870 m_prev_enable_commit_resumed (enable_commit_resumed
)
2872 infrun_debug_printf ("reason=%s", m_reason
);
2874 enable_commit_resumed
= false;
2876 for (inferior
*inf
: all_non_exited_inferiors ())
2878 process_stratum_target
*proc_target
= inf
->process_target ();
2880 if (m_prev_enable_commit_resumed
)
2882 /* This is the outermost instance: force all
2883 COMMIT_RESUMED_STATE to false. */
2884 proc_target
->commit_resumed_state
= false;
2888 /* This is not the outermost instance, we expect
2889 COMMIT_RESUMED_STATE to have been cleared by the
2890 outermost instance. */
2891 gdb_assert (!proc_target
->commit_resumed_state
);
2899 scoped_disable_commit_resumed::reset ()
2905 infrun_debug_printf ("reason=%s", m_reason
);
2907 gdb_assert (!enable_commit_resumed
);
2909 enable_commit_resumed
= m_prev_enable_commit_resumed
;
2911 if (m_prev_enable_commit_resumed
)
2913 /* This is the outermost instance, re-enable
2914 COMMIT_RESUMED_STATE on the targets where it's possible. */
2915 maybe_set_commit_resumed_all_targets ();
2919 /* This is not the outermost instance, we expect
2920 COMMIT_RESUMED_STATE to still be false. */
2921 for (inferior
*inf
: all_non_exited_inferiors ())
2923 process_stratum_target
*proc_target
= inf
->process_target ();
2924 gdb_assert (!proc_target
->commit_resumed_state
);
2931 scoped_disable_commit_resumed::~scoped_disable_commit_resumed ()
2939 scoped_disable_commit_resumed::reset_and_commit ()
2942 maybe_call_commit_resumed_all_targets ();
2947 scoped_enable_commit_resumed::scoped_enable_commit_resumed
2948 (const char *reason
)
2949 : m_reason (reason
),
2950 m_prev_enable_commit_resumed (enable_commit_resumed
)
2952 infrun_debug_printf ("reason=%s", m_reason
);
2954 if (!enable_commit_resumed
)
2956 enable_commit_resumed
= true;
2958 /* Re-enable COMMIT_RESUMED_STATE on the targets where it's
2960 maybe_set_commit_resumed_all_targets ();
2962 maybe_call_commit_resumed_all_targets ();
2968 scoped_enable_commit_resumed::~scoped_enable_commit_resumed ()
2970 infrun_debug_printf ("reason=%s", m_reason
);
2972 gdb_assert (enable_commit_resumed
);
2974 enable_commit_resumed
= m_prev_enable_commit_resumed
;
2976 if (!enable_commit_resumed
)
2978 /* Force all COMMIT_RESUMED_STATE back to false. */
2979 for (inferior
*inf
: all_non_exited_inferiors ())
2981 process_stratum_target
*proc_target
= inf
->process_target ();
2982 proc_target
->commit_resumed_state
= false;
2987 /* Check that all the targets we're about to resume are in non-stop
2988 mode. Ideally, we'd only care whether all targets support
2989 target-async, but we're not there yet. E.g., stop_all_threads
2990 doesn't know how to handle all-stop targets. Also, the remote
2991 protocol in all-stop mode is synchronous, irrespective of
2992 target-async, which means that things like a breakpoint re-set
2993 triggered by one target would try to read memory from all targets
2997 check_multi_target_resumption (process_stratum_target
*resume_target
)
2999 if (!non_stop
&& resume_target
== nullptr)
3001 scoped_restore_current_thread restore_thread
;
3003 /* This is used to track whether we're resuming more than one
3005 process_stratum_target
*first_connection
= nullptr;
3007 /* The first inferior we see with a target that does not work in
3008 always-non-stop mode. */
3009 inferior
*first_not_non_stop
= nullptr;
3011 for (inferior
*inf
: all_non_exited_inferiors ())
3013 switch_to_inferior_no_thread (inf
);
3015 if (!target_has_execution ())
3018 process_stratum_target
*proc_target
3019 = current_inferior ()->process_target();
3021 if (!target_is_non_stop_p ())
3022 first_not_non_stop
= inf
;
3024 if (first_connection
== nullptr)
3025 first_connection
= proc_target
;
3026 else if (first_connection
!= proc_target
3027 && first_not_non_stop
!= nullptr)
3029 switch_to_inferior_no_thread (first_not_non_stop
);
3031 proc_target
= current_inferior ()->process_target();
3033 error (_("Connection %d (%s) does not support "
3034 "multi-target resumption."),
3035 proc_target
->connection_number
,
3036 make_target_connection_string (proc_target
).c_str ());
3042 /* Basic routine for continuing the program in various fashions.
3044 ADDR is the address to resume at, or -1 for resume where stopped.
3045 SIGGNAL is the signal to give it, or GDB_SIGNAL_0 for none,
3046 or GDB_SIGNAL_DEFAULT for act according to how it stopped.
3048 You should call clear_proceed_status before calling proceed. */
3051 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
)
3053 INFRUN_SCOPED_DEBUG_ENTER_EXIT
;
3055 struct regcache
*regcache
;
3056 struct gdbarch
*gdbarch
;
3058 struct execution_control_state ecss
;
3059 struct execution_control_state
*ecs
= &ecss
;
3062 /* If we're stopped at a fork/vfork, follow the branch set by the
3063 "set follow-fork-mode" command; otherwise, we'll just proceed
3064 resuming the current thread. */
3065 if (!follow_fork ())
3067 /* The target for some reason decided not to resume. */
3069 if (target_can_async_p ())
3070 inferior_event_handler (INF_EXEC_COMPLETE
);
3074 /* We'll update this if & when we switch to a new thread. */
3075 previous_inferior_ptid
= inferior_ptid
;
3077 regcache
= get_current_regcache ();
3078 gdbarch
= regcache
->arch ();
3079 const address_space
*aspace
= regcache
->aspace ();
3081 pc
= regcache_read_pc_protected (regcache
);
3083 thread_info
*cur_thr
= inferior_thread ();
3085 /* Fill in with reasonable starting values. */
3086 init_thread_stepping_state (cur_thr
);
3088 gdb_assert (!thread_is_in_step_over_chain (cur_thr
));
3091 = user_visible_resume_ptid (cur_thr
->control
.stepping_command
);
3092 process_stratum_target
*resume_target
3093 = user_visible_resume_target (resume_ptid
);
3095 check_multi_target_resumption (resume_target
);
3097 if (addr
== (CORE_ADDR
) -1)
3099 if (pc
== cur_thr
->suspend
.stop_pc
3100 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
3101 && execution_direction
!= EXEC_REVERSE
)
3102 /* There is a breakpoint at the address we will resume at,
3103 step one instruction before inserting breakpoints so that
3104 we do not stop right away (and report a second hit at this
3107 Note, we don't do this in reverse, because we won't
3108 actually be executing the breakpoint insn anyway.
3109 We'll be (un-)executing the previous instruction. */
3110 cur_thr
->stepping_over_breakpoint
= 1;
3111 else if (gdbarch_single_step_through_delay_p (gdbarch
)
3112 && gdbarch_single_step_through_delay (gdbarch
,
3113 get_current_frame ()))
3114 /* We stepped onto an instruction that needs to be stepped
3115 again before re-inserting the breakpoint, do so. */
3116 cur_thr
->stepping_over_breakpoint
= 1;
3120 regcache_write_pc (regcache
, addr
);
3123 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
3124 cur_thr
->suspend
.stop_signal
= siggnal
;
3126 /* If an exception is thrown from this point on, make sure to
3127 propagate GDB's knowledge of the executing state to the
3128 frontend/user running state. */
3129 scoped_finish_thread_state
finish_state (resume_target
, resume_ptid
);
3131 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
3132 threads (e.g., we might need to set threads stepping over
3133 breakpoints first), from the user/frontend's point of view, all
3134 threads in RESUME_PTID are now running. Unless we're calling an
3135 inferior function, as in that case we pretend the inferior
3136 doesn't run at all. */
3137 if (!cur_thr
->control
.in_infcall
)
3138 set_running (resume_target
, resume_ptid
, true);
3140 infrun_debug_printf ("addr=%s, signal=%s", paddress (gdbarch
, addr
),
3141 gdb_signal_to_symbol_string (siggnal
));
3143 annotate_starting ();
3145 /* Make sure that output from GDB appears before output from the
3147 gdb_flush (gdb_stdout
);
3149 /* Since we've marked the inferior running, give it the terminal. A
3150 QUIT/Ctrl-C from here on is forwarded to the target (which can
3151 still detect attempts to unblock a stuck connection with repeated
3152 Ctrl-C from within target_pass_ctrlc). */
3153 target_terminal::inferior ();
3155 /* In a multi-threaded task we may select another thread and
3156 then continue or step.
3158 But if a thread that we're resuming had stopped at a breakpoint,
3159 it will immediately cause another breakpoint stop without any
3160 execution (i.e. it will report a breakpoint hit incorrectly). So
3161 we must step over it first.
3163 Look for threads other than the current (TP) that reported a
3164 breakpoint hit and haven't been resumed yet since. */
3166 /* If scheduler locking applies, we can avoid iterating over all
3168 if (!non_stop
&& !schedlock_applies (cur_thr
))
3170 for (thread_info
*tp
: all_non_exited_threads (resume_target
,
3173 switch_to_thread_no_regs (tp
);
3175 /* Ignore the current thread here. It's handled
3180 if (!thread_still_needs_step_over (tp
))
3183 gdb_assert (!thread_is_in_step_over_chain (tp
));
3185 infrun_debug_printf ("need to step-over [%s] first",
3186 target_pid_to_str (tp
->ptid
).c_str ());
3188 global_thread_step_over_chain_enqueue (tp
);
3191 switch_to_thread (cur_thr
);
3194 /* Enqueue the current thread last, so that we move all other
3195 threads over their breakpoints first. */
3196 if (cur_thr
->stepping_over_breakpoint
)
3197 global_thread_step_over_chain_enqueue (cur_thr
);
3199 /* If the thread isn't started, we'll still need to set its prev_pc,
3200 so that switch_back_to_stepped_thread knows the thread hasn't
3201 advanced. Must do this before resuming any thread, as in
3202 all-stop/remote, once we resume we can't send any other packet
3203 until the target stops again. */
3204 cur_thr
->prev_pc
= regcache_read_pc_protected (regcache
);
3207 scoped_disable_commit_resumed
disable_commit_resumed ("proceeding");
3209 started
= start_step_over ();
3211 if (step_over_info_valid_p ())
3213 /* Either this thread started a new in-line step over, or some
3214 other thread was already doing one. In either case, don't
3215 resume anything else until the step-over is finished. */
3217 else if (started
&& !target_is_non_stop_p ())
3219 /* A new displaced stepping sequence was started. In all-stop,
3220 we can't talk to the target anymore until it next stops. */
3222 else if (!non_stop
&& target_is_non_stop_p ())
3224 INFRUN_SCOPED_DEBUG_START_END
3225 ("resuming threads, all-stop-on-top-of-non-stop");
3227 /* In all-stop, but the target is always in non-stop mode.
3228 Start all other threads that are implicitly resumed too. */
3229 for (thread_info
*tp
: all_non_exited_threads (resume_target
,
3232 switch_to_thread_no_regs (tp
);
3234 if (!tp
->inf
->has_execution ())
3236 infrun_debug_printf ("[%s] target has no execution",
3237 target_pid_to_str (tp
->ptid
).c_str ());
3243 infrun_debug_printf ("[%s] resumed",
3244 target_pid_to_str (tp
->ptid
).c_str ());
3245 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
3249 if (thread_is_in_step_over_chain (tp
))
3251 infrun_debug_printf ("[%s] needs step-over",
3252 target_pid_to_str (tp
->ptid
).c_str ());
3256 infrun_debug_printf ("resuming %s",
3257 target_pid_to_str (tp
->ptid
).c_str ());
3259 reset_ecs (ecs
, tp
);
3260 switch_to_thread (tp
);
3261 keep_going_pass_signal (ecs
);
3262 if (!ecs
->wait_some_more
)
3263 error (_("Command aborted."));
3266 else if (!cur_thr
->resumed
&& !thread_is_in_step_over_chain (cur_thr
))
3268 /* The thread wasn't started, and isn't queued, run it now. */
3269 reset_ecs (ecs
, cur_thr
);
3270 switch_to_thread (cur_thr
);
3271 keep_going_pass_signal (ecs
);
3272 if (!ecs
->wait_some_more
)
3273 error (_("Command aborted."));
3276 disable_commit_resumed
.reset_and_commit ();
3279 finish_state
.release ();
3281 /* If we've switched threads above, switch back to the previously
3282 current thread. We don't want the user to see a different
3284 switch_to_thread (cur_thr
);
3286 /* Tell the event loop to wait for it to stop. If the target
3287 supports asynchronous execution, it'll do this from within
3289 if (!target_can_async_p ())
3290 mark_async_event_handler (infrun_async_inferior_event_token
);
3294 /* Start remote-debugging of a machine over a serial link. */
3297 start_remote (int from_tty
)
3299 inferior
*inf
= current_inferior ();
3300 inf
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
3302 /* Always go on waiting for the target, regardless of the mode. */
3303 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3304 indicate to wait_for_inferior that a target should timeout if
3305 nothing is returned (instead of just blocking). Because of this,
3306 targets expecting an immediate response need to, internally, set
3307 things up so that the target_wait() is forced to eventually
3309 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3310 differentiate to its caller what the state of the target is after
3311 the initial open has been performed. Here we're assuming that
3312 the target has stopped. It should be possible to eventually have
3313 target_open() return to the caller an indication that the target
3314 is currently running and GDB state should be set to the same as
3315 for an async run. */
3316 wait_for_inferior (inf
);
3318 /* Now that the inferior has stopped, do any bookkeeping like
3319 loading shared libraries. We want to do this before normal_stop,
3320 so that the displayed frame is up to date. */
3321 post_create_inferior (from_tty
);
3326 /* Initialize static vars when a new inferior begins. */
3329 init_wait_for_inferior (void)
3331 /* These are meaningless until the first time through wait_for_inferior. */
3333 breakpoint_init_inferior (inf_starting
);
3335 clear_proceed_status (0);
3337 nullify_last_target_wait_ptid ();
3339 previous_inferior_ptid
= inferior_ptid
;
3344 static void handle_inferior_event (struct execution_control_state
*ecs
);
3346 static void handle_step_into_function (struct gdbarch
*gdbarch
,
3347 struct execution_control_state
*ecs
);
3348 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
3349 struct execution_control_state
*ecs
);
3350 static void handle_signal_stop (struct execution_control_state
*ecs
);
3351 static void check_exception_resume (struct execution_control_state
*,
3352 struct frame_info
*);
3354 static void end_stepping_range (struct execution_control_state
*ecs
);
3355 static void stop_waiting (struct execution_control_state
*ecs
);
3356 static void keep_going (struct execution_control_state
*ecs
);
3357 static void process_event_stop_test (struct execution_control_state
*ecs
);
3358 static bool switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
3360 /* This function is attached as a "thread_stop_requested" observer.
3361 Cleanup local state that assumed the PTID was to be resumed, and
3362 report the stop to the frontend. */
3365 infrun_thread_stop_requested (ptid_t ptid
)
3367 process_stratum_target
*curr_target
= current_inferior ()->process_target ();
3369 /* PTID was requested to stop. If the thread was already stopped,
3370 but the user/frontend doesn't know about that yet (e.g., the
3371 thread had been temporarily paused for some step-over), set up
3372 for reporting the stop now. */
3373 for (thread_info
*tp
: all_threads (curr_target
, ptid
))
3375 if (tp
->state
!= THREAD_RUNNING
)
3380 /* Remove matching threads from the step-over queue, so
3381 start_step_over doesn't try to resume them
3383 if (thread_is_in_step_over_chain (tp
))
3384 global_thread_step_over_chain_remove (tp
);
3386 /* If the thread is stopped, but the user/frontend doesn't
3387 know about that yet, queue a pending event, as if the
3388 thread had just stopped now. Unless the thread already had
3390 if (!tp
->suspend
.waitstatus_pending_p
)
3392 tp
->suspend
.waitstatus_pending_p
= 1;
3393 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_STOPPED
;
3394 tp
->suspend
.waitstatus
.value
.sig
= GDB_SIGNAL_0
;
3397 /* Clear the inline-frame state, since we're re-processing the
3399 clear_inline_frame_state (tp
);
3401 /* If this thread was paused because some other thread was
3402 doing an inline-step over, let that finish first. Once
3403 that happens, we'll restart all threads and consume pending
3404 stop events then. */
3405 if (step_over_info_valid_p ())
3408 /* Otherwise we can process the (new) pending event now. Set
3409 it so this pending event is considered by
3416 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
3418 if (target_last_proc_target
== tp
->inf
->process_target ()
3419 && target_last_wait_ptid
== tp
->ptid
)
3420 nullify_last_target_wait_ptid ();
3423 /* Delete the step resume, single-step and longjmp/exception resume
3424 breakpoints of TP. */
3427 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
3429 delete_step_resume_breakpoint (tp
);
3430 delete_exception_resume_breakpoint (tp
);
3431 delete_single_step_breakpoints (tp
);
3434 /* If the target still has execution, call FUNC for each thread that
3435 just stopped. In all-stop, that's all the non-exited threads; in
3436 non-stop, that's the current thread, only. */
3438 typedef void (*for_each_just_stopped_thread_callback_func
)
3439 (struct thread_info
*tp
);
3442 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
3444 if (!target_has_execution () || inferior_ptid
== null_ptid
)
3447 if (target_is_non_stop_p ())
3449 /* If in non-stop mode, only the current thread stopped. */
3450 func (inferior_thread ());
3454 /* In all-stop mode, all threads have stopped. */
3455 for (thread_info
*tp
: all_non_exited_threads ())
3460 /* Delete the step resume and longjmp/exception resume breakpoints of
3461 the threads that just stopped. */
3464 delete_just_stopped_threads_infrun_breakpoints (void)
3466 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3469 /* Delete the single-step breakpoints of the threads that just
3473 delete_just_stopped_threads_single_step_breakpoints (void)
3475 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3481 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3482 const struct target_waitstatus
*ws
)
3484 infrun_debug_printf ("target_wait (%d.%ld.%ld [%s], status) =",
3488 target_pid_to_str (waiton_ptid
).c_str ());
3489 infrun_debug_printf (" %d.%ld.%ld [%s],",
3493 target_pid_to_str (result_ptid
).c_str ());
3494 infrun_debug_printf (" %s", target_waitstatus_to_string (ws
).c_str ());
3497 /* Select a thread at random, out of those which are resumed and have
3500 static struct thread_info
*
3501 random_pending_event_thread (inferior
*inf
, ptid_t waiton_ptid
)
3505 auto has_event
= [&] (thread_info
*tp
)
3507 return (tp
->ptid
.matches (waiton_ptid
)
3509 && tp
->suspend
.waitstatus_pending_p
);
3512 /* First see how many events we have. Count only resumed threads
3513 that have an event pending. */
3514 for (thread_info
*tp
: inf
->non_exited_threads ())
3518 if (num_events
== 0)
3521 /* Now randomly pick a thread out of those that have had events. */
3522 int random_selector
= (int) ((num_events
* (double) rand ())
3523 / (RAND_MAX
+ 1.0));
3526 infrun_debug_printf ("Found %d events, selecting #%d",
3527 num_events
, random_selector
);
3529 /* Select the Nth thread that has had an event. */
3530 for (thread_info
*tp
: inf
->non_exited_threads ())
3532 if (random_selector
-- == 0)
3535 gdb_assert_not_reached ("event thread not found");
3538 /* Wrapper for target_wait that first checks whether threads have
3539 pending statuses to report before actually asking the target for
3540 more events. INF is the inferior we're using to call target_wait
3544 do_target_wait_1 (inferior
*inf
, ptid_t ptid
,
3545 target_waitstatus
*status
, target_wait_flags options
)
3548 struct thread_info
*tp
;
3550 /* We know that we are looking for an event in the target of inferior
3551 INF, but we don't know which thread the event might come from. As
3552 such we want to make sure that INFERIOR_PTID is reset so that none of
3553 the wait code relies on it - doing so is always a mistake. */
3554 switch_to_inferior_no_thread (inf
);
3556 /* First check if there is a resumed thread with a wait status
3558 if (ptid
== minus_one_ptid
|| ptid
.is_pid ())
3560 tp
= random_pending_event_thread (inf
, ptid
);
3564 infrun_debug_printf ("Waiting for specific thread %s.",
3565 target_pid_to_str (ptid
).c_str ());
3567 /* We have a specific thread to check. */
3568 tp
= find_thread_ptid (inf
, ptid
);
3569 gdb_assert (tp
!= NULL
);
3570 if (!tp
->suspend
.waitstatus_pending_p
)
3575 && (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3576 || tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
3578 struct regcache
*regcache
= get_thread_regcache (tp
);
3579 struct gdbarch
*gdbarch
= regcache
->arch ();
3583 pc
= regcache_read_pc (regcache
);
3585 if (pc
!= tp
->suspend
.stop_pc
)
3587 infrun_debug_printf ("PC of %s changed. was=%s, now=%s",
3588 target_pid_to_str (tp
->ptid
).c_str (),
3589 paddress (gdbarch
, tp
->suspend
.stop_pc
),
3590 paddress (gdbarch
, pc
));
3593 else if (!breakpoint_inserted_here_p (regcache
->aspace (), pc
))
3595 infrun_debug_printf ("previous breakpoint of %s, at %s gone",
3596 target_pid_to_str (tp
->ptid
).c_str (),
3597 paddress (gdbarch
, pc
));
3604 infrun_debug_printf ("pending event of %s cancelled.",
3605 target_pid_to_str (tp
->ptid
).c_str ());
3607 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_SPURIOUS
;
3608 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3614 infrun_debug_printf ("Using pending wait status %s for %s.",
3615 target_waitstatus_to_string
3616 (&tp
->suspend
.waitstatus
).c_str (),
3617 target_pid_to_str (tp
->ptid
).c_str ());
3619 /* Now that we've selected our final event LWP, un-adjust its PC
3620 if it was a software breakpoint (and the target doesn't
3621 always adjust the PC itself). */
3622 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3623 && !target_supports_stopped_by_sw_breakpoint ())
3625 struct regcache
*regcache
;
3626 struct gdbarch
*gdbarch
;
3629 regcache
= get_thread_regcache (tp
);
3630 gdbarch
= regcache
->arch ();
3632 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3637 pc
= regcache_read_pc (regcache
);
3638 regcache_write_pc (regcache
, pc
+ decr_pc
);
3642 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3643 *status
= tp
->suspend
.waitstatus
;
3644 tp
->suspend
.waitstatus_pending_p
= 0;
3646 /* Wake up the event loop again, until all pending events are
3648 if (target_is_async_p ())
3649 mark_async_event_handler (infrun_async_inferior_event_token
);
3653 /* But if we don't find one, we'll have to wait. */
3655 /* We can't ask a non-async target to do a non-blocking wait, so this will be
3657 if (!target_can_async_p ())
3658 options
&= ~TARGET_WNOHANG
;
3660 if (deprecated_target_wait_hook
)
3661 event_ptid
= deprecated_target_wait_hook (ptid
, status
, options
);
3663 event_ptid
= target_wait (ptid
, status
, options
);
3668 /* Wrapper for target_wait that first checks whether threads have
3669 pending statuses to report before actually asking the target for
3670 more events. Polls for events from all inferiors/targets. */
3673 do_target_wait (ptid_t wait_ptid
, execution_control_state
*ecs
,
3674 target_wait_flags options
)
3676 int num_inferiors
= 0;
3677 int random_selector
;
3679 /* For fairness, we pick the first inferior/target to poll at random
3680 out of all inferiors that may report events, and then continue
3681 polling the rest of the inferior list starting from that one in a
3682 circular fashion until the whole list is polled once. */
3684 auto inferior_matches
= [&wait_ptid
] (inferior
*inf
)
3686 return (inf
->process_target () != NULL
3687 && ptid_t (inf
->pid
).matches (wait_ptid
));
3690 /* First see how many matching inferiors we have. */
3691 for (inferior
*inf
: all_inferiors ())
3692 if (inferior_matches (inf
))
3695 if (num_inferiors
== 0)
3697 ecs
->ws
.kind
= TARGET_WAITKIND_IGNORE
;
3701 /* Now randomly pick an inferior out of those that matched. */
3702 random_selector
= (int)
3703 ((num_inferiors
* (double) rand ()) / (RAND_MAX
+ 1.0));
3705 if (num_inferiors
> 1)
3706 infrun_debug_printf ("Found %d inferiors, starting at #%d",
3707 num_inferiors
, random_selector
);
3709 /* Select the Nth inferior that matched. */
3711 inferior
*selected
= nullptr;
3713 for (inferior
*inf
: all_inferiors ())
3714 if (inferior_matches (inf
))
3715 if (random_selector
-- == 0)
3721 /* Now poll for events out of each of the matching inferior's
3722 targets, starting from the selected one. */
3724 auto do_wait
= [&] (inferior
*inf
)
3726 ecs
->ptid
= do_target_wait_1 (inf
, wait_ptid
, &ecs
->ws
, options
);
3727 ecs
->target
= inf
->process_target ();
3728 return (ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
);
3731 /* Needed in 'all-stop + target-non-stop' mode, because we end up
3732 here spuriously after the target is all stopped and we've already
3733 reported the stop to the user, polling for events. */
3734 scoped_restore_current_thread restore_thread
;
3736 int inf_num
= selected
->num
;
3737 for (inferior
*inf
= selected
; inf
!= NULL
; inf
= inf
->next
)
3738 if (inferior_matches (inf
))
3742 for (inferior
*inf
= inferior_list
;
3743 inf
!= NULL
&& inf
->num
< inf_num
;
3745 if (inferior_matches (inf
))
3749 ecs
->ws
.kind
= TARGET_WAITKIND_IGNORE
;
3753 /* An event reported by wait_one. */
3755 struct wait_one_event
3757 /* The target the event came out of. */
3758 process_stratum_target
*target
;
3760 /* The PTID the event was for. */
3763 /* The waitstatus. */
3764 target_waitstatus ws
;
3767 static bool handle_one (const wait_one_event
&event
);
3768 static void restart_threads (struct thread_info
*event_thread
);
3770 /* Prepare and stabilize the inferior for detaching it. E.g.,
3771 detaching while a thread is displaced stepping is a recipe for
3772 crashing it, as nothing would readjust the PC out of the scratch
3776 prepare_for_detach (void)
3778 struct inferior
*inf
= current_inferior ();
3779 ptid_t pid_ptid
= ptid_t (inf
->pid
);
3780 scoped_restore_current_thread restore_thread
;
3782 scoped_restore restore_detaching
= make_scoped_restore (&inf
->detaching
, true);
3784 /* Remove all threads of INF from the global step-over chain. We
3785 want to stop any ongoing step-over, not start any new one. */
3787 for (thread_info
*tp
= global_thread_step_over_chain_head
;
3791 next
= global_thread_step_over_chain_next (tp
);
3793 global_thread_step_over_chain_remove (tp
);
3796 /* If we were already in the middle of an inline step-over, and the
3797 thread stepping belongs to the inferior we're detaching, we need
3798 to restart the threads of other inferiors. */
3799 if (step_over_info
.thread
!= -1)
3801 infrun_debug_printf ("inline step-over in-process while detaching");
3803 thread_info
*thr
= find_thread_global_id (step_over_info
.thread
);
3804 if (thr
->inf
== inf
)
3806 /* Since we removed threads of INF from the step-over chain,
3807 we know this won't start a step-over for INF. */
3808 clear_step_over_info ();
3810 if (target_is_non_stop_p ())
3812 /* Start a new step-over in another thread if there's
3813 one that needs it. */
3816 /* Restart all other threads (except the
3817 previously-stepping thread, since that one is still
3819 if (!step_over_info_valid_p ())
3820 restart_threads (thr
);
3825 if (displaced_step_in_progress (inf
))
3827 infrun_debug_printf ("displaced-stepping in-process while detaching");
3829 /* Stop threads currently displaced stepping, aborting it. */
3831 for (thread_info
*thr
: inf
->non_exited_threads ())
3833 if (thr
->displaced_step_state
.in_progress ())
3837 if (!thr
->stop_requested
)
3839 target_stop (thr
->ptid
);
3840 thr
->stop_requested
= true;
3844 thr
->resumed
= false;
3848 while (displaced_step_in_progress (inf
))
3850 wait_one_event event
;
3852 event
.target
= inf
->process_target ();
3853 event
.ptid
= do_target_wait_1 (inf
, pid_ptid
, &event
.ws
, 0);
3856 print_target_wait_results (pid_ptid
, event
.ptid
, &event
.ws
);
3861 /* It's OK to leave some of the threads of INF stopped, since
3862 they'll be detached shortly. */
3866 /* Wait for control to return from inferior to debugger.
3868 If inferior gets a signal, we may decide to start it up again
3869 instead of returning. That is why there is a loop in this function.
3870 When this function actually returns it means the inferior
3871 should be left stopped and GDB should read more commands. */
3874 wait_for_inferior (inferior
*inf
)
3876 infrun_debug_printf ("wait_for_inferior ()");
3878 SCOPE_EXIT
{ delete_just_stopped_threads_infrun_breakpoints (); };
3880 /* If an error happens while handling the event, propagate GDB's
3881 knowledge of the executing state to the frontend/user running
3883 scoped_finish_thread_state finish_state
3884 (inf
->process_target (), minus_one_ptid
);
3888 struct execution_control_state ecss
;
3889 struct execution_control_state
*ecs
= &ecss
;
3891 memset (ecs
, 0, sizeof (*ecs
));
3893 overlay_cache_invalid
= 1;
3895 /* Flush target cache before starting to handle each event.
3896 Target was running and cache could be stale. This is just a
3897 heuristic. Running threads may modify target memory, but we
3898 don't get any event. */
3899 target_dcache_invalidate ();
3901 ecs
->ptid
= do_target_wait_1 (inf
, minus_one_ptid
, &ecs
->ws
, 0);
3902 ecs
->target
= inf
->process_target ();
3905 print_target_wait_results (minus_one_ptid
, ecs
->ptid
, &ecs
->ws
);
3907 /* Now figure out what to do with the result of the result. */
3908 handle_inferior_event (ecs
);
3910 if (!ecs
->wait_some_more
)
3914 /* No error, don't finish the state yet. */
3915 finish_state
.release ();
3918 /* Cleanup that reinstalls the readline callback handler, if the
3919 target is running in the background. If while handling the target
3920 event something triggered a secondary prompt, like e.g., a
3921 pagination prompt, we'll have removed the callback handler (see
3922 gdb_readline_wrapper_line). Need to do this as we go back to the
3923 event loop, ready to process further input. Note this has no
3924 effect if the handler hasn't actually been removed, because calling
3925 rl_callback_handler_install resets the line buffer, thus losing
3929 reinstall_readline_callback_handler_cleanup ()
3931 struct ui
*ui
= current_ui
;
3935 /* We're not going back to the top level event loop yet. Don't
3936 install the readline callback, as it'd prep the terminal,
3937 readline-style (raw, noecho) (e.g., --batch). We'll install
3938 it the next time the prompt is displayed, when we're ready
3943 if (ui
->command_editing
&& ui
->prompt_state
!= PROMPT_BLOCKED
)
3944 gdb_rl_callback_handler_reinstall ();
3947 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3948 that's just the event thread. In all-stop, that's all threads. */
3951 clean_up_just_stopped_threads_fsms (struct execution_control_state
*ecs
)
3953 if (ecs
->event_thread
!= NULL
3954 && ecs
->event_thread
->thread_fsm
!= NULL
)
3955 ecs
->event_thread
->thread_fsm
->clean_up (ecs
->event_thread
);
3959 for (thread_info
*thr
: all_non_exited_threads ())
3961 if (thr
->thread_fsm
== NULL
)
3963 if (thr
== ecs
->event_thread
)
3966 switch_to_thread (thr
);
3967 thr
->thread_fsm
->clean_up (thr
);
3970 if (ecs
->event_thread
!= NULL
)
3971 switch_to_thread (ecs
->event_thread
);
3975 /* Helper for all_uis_check_sync_execution_done that works on the
3979 check_curr_ui_sync_execution_done (void)
3981 struct ui
*ui
= current_ui
;
3983 if (ui
->prompt_state
== PROMPT_NEEDED
3985 && !gdb_in_secondary_prompt_p (ui
))
3987 target_terminal::ours ();
3988 gdb::observers::sync_execution_done
.notify ();
3989 ui_register_input_event_handler (ui
);
3996 all_uis_check_sync_execution_done (void)
3998 SWITCH_THRU_ALL_UIS ()
4000 check_curr_ui_sync_execution_done ();
4007 all_uis_on_sync_execution_starting (void)
4009 SWITCH_THRU_ALL_UIS ()
4011 if (current_ui
->prompt_state
== PROMPT_NEEDED
)
4012 async_disable_stdin ();
4016 /* Asynchronous version of wait_for_inferior. It is called by the
4017 event loop whenever a change of state is detected on the file
4018 descriptor corresponding to the target. It can be called more than
4019 once to complete a single execution command. In such cases we need
4020 to keep the state in a global variable ECSS. If it is the last time
4021 that this function is called for a single execution command, then
4022 report to the user that the inferior has stopped, and do the
4023 necessary cleanups. */
4026 fetch_inferior_event ()
4028 INFRUN_SCOPED_DEBUG_ENTER_EXIT
;
4030 struct execution_control_state ecss
;
4031 struct execution_control_state
*ecs
= &ecss
;
4034 memset (ecs
, 0, sizeof (*ecs
));
4036 /* Events are always processed with the main UI as current UI. This
4037 way, warnings, debug output, etc. are always consistently sent to
4038 the main console. */
4039 scoped_restore save_ui
= make_scoped_restore (¤t_ui
, main_ui
);
4041 /* Temporarily disable pagination. Otherwise, the user would be
4042 given an option to press 'q' to quit, which would cause an early
4043 exit and could leave GDB in a half-baked state. */
4044 scoped_restore save_pagination
4045 = make_scoped_restore (&pagination_enabled
, false);
4047 /* End up with readline processing input, if necessary. */
4049 SCOPE_EXIT
{ reinstall_readline_callback_handler_cleanup (); };
4051 /* We're handling a live event, so make sure we're doing live
4052 debugging. If we're looking at traceframes while the target is
4053 running, we're going to need to get back to that mode after
4054 handling the event. */
4055 gdb::optional
<scoped_restore_current_traceframe
> maybe_restore_traceframe
;
4058 maybe_restore_traceframe
.emplace ();
4059 set_current_traceframe (-1);
4062 /* The user/frontend should not notice a thread switch due to
4063 internal events. Make sure we revert to the user selected
4064 thread and frame after handling the event and running any
4065 breakpoint commands. */
4066 scoped_restore_current_thread restore_thread
;
4068 overlay_cache_invalid
= 1;
4069 /* Flush target cache before starting to handle each event. Target
4070 was running and cache could be stale. This is just a heuristic.
4071 Running threads may modify target memory, but we don't get any
4073 target_dcache_invalidate ();
4075 scoped_restore save_exec_dir
4076 = make_scoped_restore (&execution_direction
,
4077 target_execution_direction ());
4079 /* Allow targets to pause their resumed threads while we handle
4081 scoped_disable_commit_resumed
disable_commit_resumed ("handling event");
4083 if (!do_target_wait (minus_one_ptid
, ecs
, TARGET_WNOHANG
))
4085 infrun_debug_printf ("do_target_wait returned no event");
4086 disable_commit_resumed
.reset_and_commit ();
4090 gdb_assert (ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
);
4092 /* Switch to the target that generated the event, so we can do
4094 switch_to_target_no_thread (ecs
->target
);
4097 print_target_wait_results (minus_one_ptid
, ecs
->ptid
, &ecs
->ws
);
4099 /* If an error happens while handling the event, propagate GDB's
4100 knowledge of the executing state to the frontend/user running
4102 ptid_t finish_ptid
= !target_is_non_stop_p () ? minus_one_ptid
: ecs
->ptid
;
4103 scoped_finish_thread_state
finish_state (ecs
->target
, finish_ptid
);
4105 /* Get executed before scoped_restore_current_thread above to apply
4106 still for the thread which has thrown the exception. */
4107 auto defer_bpstat_clear
4108 = make_scope_exit (bpstat_clear_actions
);
4109 auto defer_delete_threads
4110 = make_scope_exit (delete_just_stopped_threads_infrun_breakpoints
);
4112 /* Now figure out what to do with the result of the result. */
4113 handle_inferior_event (ecs
);
4115 if (!ecs
->wait_some_more
)
4117 struct inferior
*inf
= find_inferior_ptid (ecs
->target
, ecs
->ptid
);
4118 bool should_stop
= true;
4119 struct thread_info
*thr
= ecs
->event_thread
;
4121 delete_just_stopped_threads_infrun_breakpoints ();
4125 struct thread_fsm
*thread_fsm
= thr
->thread_fsm
;
4127 if (thread_fsm
!= NULL
)
4128 should_stop
= thread_fsm
->should_stop (thr
);
4137 bool should_notify_stop
= true;
4140 clean_up_just_stopped_threads_fsms (ecs
);
4142 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
4143 should_notify_stop
= thr
->thread_fsm
->should_notify_stop ();
4145 if (should_notify_stop
)
4147 /* We may not find an inferior if this was a process exit. */
4148 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
4149 proceeded
= normal_stop ();
4154 inferior_event_handler (INF_EXEC_COMPLETE
);
4158 /* If we got a TARGET_WAITKIND_NO_RESUMED event, then the
4159 previously selected thread is gone. We have two
4160 choices - switch to no thread selected, or restore the
4161 previously selected thread (now exited). We chose the
4162 later, just because that's what GDB used to do. After
4163 this, "info threads" says "The current thread <Thread
4164 ID 2> has terminated." instead of "No thread
4168 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
4169 restore_thread
.dont_restore ();
4173 defer_delete_threads
.release ();
4174 defer_bpstat_clear
.release ();
4176 /* No error, don't finish the thread states yet. */
4177 finish_state
.release ();
4179 disable_commit_resumed
.reset_and_commit ();
4181 /* This scope is used to ensure that readline callbacks are
4182 reinstalled here. */
4185 /* If a UI was in sync execution mode, and now isn't, restore its
4186 prompt (a synchronous execution command has finished, and we're
4187 ready for input). */
4188 all_uis_check_sync_execution_done ();
4191 && exec_done_display_p
4192 && (inferior_ptid
== null_ptid
4193 || inferior_thread ()->state
!= THREAD_RUNNING
))
4194 printf_unfiltered (_("completed.\n"));
4200 set_step_info (thread_info
*tp
, struct frame_info
*frame
,
4201 struct symtab_and_line sal
)
4203 /* This can be removed once this function no longer implicitly relies on the
4204 inferior_ptid value. */
4205 gdb_assert (inferior_ptid
== tp
->ptid
);
4207 tp
->control
.step_frame_id
= get_frame_id (frame
);
4208 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
4210 tp
->current_symtab
= sal
.symtab
;
4211 tp
->current_line
= sal
.line
;
4214 /* Clear context switchable stepping state. */
4217 init_thread_stepping_state (struct thread_info
*tss
)
4219 tss
->stepped_breakpoint
= 0;
4220 tss
->stepping_over_breakpoint
= 0;
4221 tss
->stepping_over_watchpoint
= 0;
4222 tss
->step_after_step_resume_breakpoint
= 0;
4228 set_last_target_status (process_stratum_target
*target
, ptid_t ptid
,
4229 target_waitstatus status
)
4231 target_last_proc_target
= target
;
4232 target_last_wait_ptid
= ptid
;
4233 target_last_waitstatus
= status
;
4239 get_last_target_status (process_stratum_target
**target
, ptid_t
*ptid
,
4240 target_waitstatus
*status
)
4242 if (target
!= nullptr)
4243 *target
= target_last_proc_target
;
4244 if (ptid
!= nullptr)
4245 *ptid
= target_last_wait_ptid
;
4246 if (status
!= nullptr)
4247 *status
= target_last_waitstatus
;
4253 nullify_last_target_wait_ptid (void)
4255 target_last_proc_target
= nullptr;
4256 target_last_wait_ptid
= minus_one_ptid
;
4257 target_last_waitstatus
= {};
4260 /* Switch thread contexts. */
4263 context_switch (execution_control_state
*ecs
)
4265 if (ecs
->ptid
!= inferior_ptid
4266 && (inferior_ptid
== null_ptid
4267 || ecs
->event_thread
!= inferior_thread ()))
4269 infrun_debug_printf ("Switching context from %s to %s",
4270 target_pid_to_str (inferior_ptid
).c_str (),
4271 target_pid_to_str (ecs
->ptid
).c_str ());
4274 switch_to_thread (ecs
->event_thread
);
4277 /* If the target can't tell whether we've hit breakpoints
4278 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
4279 check whether that could have been caused by a breakpoint. If so,
4280 adjust the PC, per gdbarch_decr_pc_after_break. */
4283 adjust_pc_after_break (struct thread_info
*thread
,
4284 struct target_waitstatus
*ws
)
4286 struct regcache
*regcache
;
4287 struct gdbarch
*gdbarch
;
4288 CORE_ADDR breakpoint_pc
, decr_pc
;
4290 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
4291 we aren't, just return.
4293 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
4294 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
4295 implemented by software breakpoints should be handled through the normal
4298 NOTE drow/2004-01-31: On some targets, breakpoints may generate
4299 different signals (SIGILL or SIGEMT for instance), but it is less
4300 clear where the PC is pointing afterwards. It may not match
4301 gdbarch_decr_pc_after_break. I don't know any specific target that
4302 generates these signals at breakpoints (the code has been in GDB since at
4303 least 1992) so I can not guess how to handle them here.
4305 In earlier versions of GDB, a target with
4306 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
4307 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
4308 target with both of these set in GDB history, and it seems unlikely to be
4309 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
4311 if (ws
->kind
!= TARGET_WAITKIND_STOPPED
)
4314 if (ws
->value
.sig
!= GDB_SIGNAL_TRAP
)
4317 /* In reverse execution, when a breakpoint is hit, the instruction
4318 under it has already been de-executed. The reported PC always
4319 points at the breakpoint address, so adjusting it further would
4320 be wrong. E.g., consider this case on a decr_pc_after_break == 1
4323 B1 0x08000000 : INSN1
4324 B2 0x08000001 : INSN2
4326 PC -> 0x08000003 : INSN4
4328 Say you're stopped at 0x08000003 as above. Reverse continuing
4329 from that point should hit B2 as below. Reading the PC when the
4330 SIGTRAP is reported should read 0x08000001 and INSN2 should have
4331 been de-executed already.
4333 B1 0x08000000 : INSN1
4334 B2 PC -> 0x08000001 : INSN2
4338 We can't apply the same logic as for forward execution, because
4339 we would wrongly adjust the PC to 0x08000000, since there's a
4340 breakpoint at PC - 1. We'd then report a hit on B1, although
4341 INSN1 hadn't been de-executed yet. Doing nothing is the correct
4343 if (execution_direction
== EXEC_REVERSE
)
4346 /* If the target can tell whether the thread hit a SW breakpoint,
4347 trust it. Targets that can tell also adjust the PC
4349 if (target_supports_stopped_by_sw_breakpoint ())
4352 /* Note that relying on whether a breakpoint is planted in memory to
4353 determine this can fail. E.g,. the breakpoint could have been
4354 removed since. Or the thread could have been told to step an
4355 instruction the size of a breakpoint instruction, and only
4356 _after_ was a breakpoint inserted at its address. */
4358 /* If this target does not decrement the PC after breakpoints, then
4359 we have nothing to do. */
4360 regcache
= get_thread_regcache (thread
);
4361 gdbarch
= regcache
->arch ();
4363 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
4367 const address_space
*aspace
= regcache
->aspace ();
4369 /* Find the location where (if we've hit a breakpoint) the
4370 breakpoint would be. */
4371 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
4373 /* If the target can't tell whether a software breakpoint triggered,
4374 fallback to figuring it out based on breakpoints we think were
4375 inserted in the target, and on whether the thread was stepped or
4378 /* Check whether there actually is a software breakpoint inserted at
4381 If in non-stop mode, a race condition is possible where we've
4382 removed a breakpoint, but stop events for that breakpoint were
4383 already queued and arrive later. To suppress those spurious
4384 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
4385 and retire them after a number of stop events are reported. Note
4386 this is an heuristic and can thus get confused. The real fix is
4387 to get the "stopped by SW BP and needs adjustment" info out of
4388 the target/kernel (and thus never reach here; see above). */
4389 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
4390 || (target_is_non_stop_p ()
4391 && moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
4393 gdb::optional
<scoped_restore_tmpl
<int>> restore_operation_disable
;
4395 if (record_full_is_used ())
4396 restore_operation_disable
.emplace
4397 (record_full_gdb_operation_disable_set ());
4399 /* When using hardware single-step, a SIGTRAP is reported for both
4400 a completed single-step and a software breakpoint. Need to
4401 differentiate between the two, as the latter needs adjusting
4402 but the former does not.
4404 The SIGTRAP can be due to a completed hardware single-step only if
4405 - we didn't insert software single-step breakpoints
4406 - this thread is currently being stepped
4408 If any of these events did not occur, we must have stopped due
4409 to hitting a software breakpoint, and have to back up to the
4412 As a special case, we could have hardware single-stepped a
4413 software breakpoint. In this case (prev_pc == breakpoint_pc),
4414 we also need to back up to the breakpoint address. */
4416 if (thread_has_single_step_breakpoints_set (thread
)
4417 || !currently_stepping (thread
)
4418 || (thread
->stepped_breakpoint
4419 && thread
->prev_pc
== breakpoint_pc
))
4420 regcache_write_pc (regcache
, breakpoint_pc
);
4425 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
4427 for (frame
= get_prev_frame (frame
);
4429 frame
= get_prev_frame (frame
))
4431 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
4434 if (get_frame_type (frame
) != INLINE_FRAME
)
4441 /* Look for an inline frame that is marked for skip.
4442 If PREV_FRAME is TRUE start at the previous frame,
4443 otherwise start at the current frame. Stop at the
4444 first non-inline frame, or at the frame where the
4448 inline_frame_is_marked_for_skip (bool prev_frame
, struct thread_info
*tp
)
4450 struct frame_info
*frame
= get_current_frame ();
4453 frame
= get_prev_frame (frame
);
4455 for (; frame
!= NULL
; frame
= get_prev_frame (frame
))
4457 const char *fn
= NULL
;
4458 symtab_and_line sal
;
4461 if (frame_id_eq (get_frame_id (frame
), tp
->control
.step_frame_id
))
4463 if (get_frame_type (frame
) != INLINE_FRAME
)
4466 sal
= find_frame_sal (frame
);
4467 sym
= get_frame_function (frame
);
4470 fn
= sym
->print_name ();
4473 && function_name_is_marked_for_skip (fn
, sal
))
4480 /* If the event thread has the stop requested flag set, pretend it
4481 stopped for a GDB_SIGNAL_0 (i.e., as if it stopped due to
4485 handle_stop_requested (struct execution_control_state
*ecs
)
4487 if (ecs
->event_thread
->stop_requested
)
4489 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
4490 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
4491 handle_signal_stop (ecs
);
4497 /* Auxiliary function that handles syscall entry/return events.
4498 It returns true if the inferior should keep going (and GDB
4499 should ignore the event), or false if the event deserves to be
4503 handle_syscall_event (struct execution_control_state
*ecs
)
4505 struct regcache
*regcache
;
4508 context_switch (ecs
);
4510 regcache
= get_thread_regcache (ecs
->event_thread
);
4511 syscall_number
= ecs
->ws
.value
.syscall_number
;
4512 ecs
->event_thread
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4514 if (catch_syscall_enabled () > 0
4515 && catching_syscall_number (syscall_number
) > 0)
4517 infrun_debug_printf ("syscall number=%d", syscall_number
);
4519 ecs
->event_thread
->control
.stop_bpstat
4520 = bpstat_stop_status (regcache
->aspace (),
4521 ecs
->event_thread
->suspend
.stop_pc
,
4522 ecs
->event_thread
, &ecs
->ws
);
4524 if (handle_stop_requested (ecs
))
4527 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4529 /* Catchpoint hit. */
4534 if (handle_stop_requested (ecs
))
4537 /* If no catchpoint triggered for this, then keep going. */
4543 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4546 fill_in_stop_func (struct gdbarch
*gdbarch
,
4547 struct execution_control_state
*ecs
)
4549 if (!ecs
->stop_func_filled_in
)
4552 const general_symbol_info
*gsi
;
4554 /* Don't care about return value; stop_func_start and stop_func_name
4555 will both be 0 if it doesn't work. */
4556 find_pc_partial_function_sym (ecs
->event_thread
->suspend
.stop_pc
,
4558 &ecs
->stop_func_start
,
4559 &ecs
->stop_func_end
,
4561 ecs
->stop_func_name
= gsi
== nullptr ? nullptr : gsi
->print_name ();
4563 /* The call to find_pc_partial_function, above, will set
4564 stop_func_start and stop_func_end to the start and end
4565 of the range containing the stop pc. If this range
4566 contains the entry pc for the block (which is always the
4567 case for contiguous blocks), advance stop_func_start past
4568 the function's start offset and entrypoint. Note that
4569 stop_func_start is NOT advanced when in a range of a
4570 non-contiguous block that does not contain the entry pc. */
4571 if (block
!= nullptr
4572 && ecs
->stop_func_start
<= BLOCK_ENTRY_PC (block
)
4573 && BLOCK_ENTRY_PC (block
) < ecs
->stop_func_end
)
4575 ecs
->stop_func_start
4576 += gdbarch_deprecated_function_start_offset (gdbarch
);
4578 if (gdbarch_skip_entrypoint_p (gdbarch
))
4579 ecs
->stop_func_start
4580 = gdbarch_skip_entrypoint (gdbarch
, ecs
->stop_func_start
);
4583 ecs
->stop_func_filled_in
= 1;
4588 /* Return the STOP_SOON field of the inferior pointed at by ECS. */
4590 static enum stop_kind
4591 get_inferior_stop_soon (execution_control_state
*ecs
)
4593 struct inferior
*inf
= find_inferior_ptid (ecs
->target
, ecs
->ptid
);
4595 gdb_assert (inf
!= NULL
);
4596 return inf
->control
.stop_soon
;
4599 /* Poll for one event out of the current target. Store the resulting
4600 waitstatus in WS, and return the event ptid. Does not block. */
4603 poll_one_curr_target (struct target_waitstatus
*ws
)
4607 overlay_cache_invalid
= 1;
4609 /* Flush target cache before starting to handle each event.
4610 Target was running and cache could be stale. This is just a
4611 heuristic. Running threads may modify target memory, but we
4612 don't get any event. */
4613 target_dcache_invalidate ();
4615 if (deprecated_target_wait_hook
)
4616 event_ptid
= deprecated_target_wait_hook (minus_one_ptid
, ws
, TARGET_WNOHANG
);
4618 event_ptid
= target_wait (minus_one_ptid
, ws
, TARGET_WNOHANG
);
4621 print_target_wait_results (minus_one_ptid
, event_ptid
, ws
);
4626 /* Wait for one event out of any target. */
4628 static wait_one_event
4633 for (inferior
*inf
: all_inferiors ())
4635 process_stratum_target
*target
= inf
->process_target ();
4637 || !target
->is_async_p ()
4638 || !target
->threads_executing
)
4641 switch_to_inferior_no_thread (inf
);
4643 wait_one_event event
;
4644 event
.target
= target
;
4645 event
.ptid
= poll_one_curr_target (&event
.ws
);
4647 if (event
.ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4649 /* If nothing is resumed, remove the target from the
4653 else if (event
.ws
.kind
!= TARGET_WAITKIND_IGNORE
)
4657 /* Block waiting for some event. */
4664 for (inferior
*inf
: all_inferiors ())
4666 process_stratum_target
*target
= inf
->process_target ();
4668 || !target
->is_async_p ()
4669 || !target
->threads_executing
)
4672 int fd
= target
->async_wait_fd ();
4673 FD_SET (fd
, &readfds
);
4680 /* No waitable targets left. All must be stopped. */
4681 return {NULL
, minus_one_ptid
, {TARGET_WAITKIND_NO_RESUMED
}};
4686 int numfds
= interruptible_select (nfds
, &readfds
, 0, NULL
, 0);
4692 perror_with_name ("interruptible_select");
4697 /* Save the thread's event and stop reason to process it later. */
4700 save_waitstatus (struct thread_info
*tp
, const target_waitstatus
*ws
)
4702 infrun_debug_printf ("saving status %s for %d.%ld.%ld",
4703 target_waitstatus_to_string (ws
).c_str (),
4708 /* Record for later. */
4709 tp
->suspend
.waitstatus
= *ws
;
4710 tp
->suspend
.waitstatus_pending_p
= 1;
4712 if (ws
->kind
== TARGET_WAITKIND_STOPPED
4713 && ws
->value
.sig
== GDB_SIGNAL_TRAP
)
4715 struct regcache
*regcache
= get_thread_regcache (tp
);
4716 const address_space
*aspace
= regcache
->aspace ();
4717 CORE_ADDR pc
= regcache_read_pc (regcache
);
4719 adjust_pc_after_break (tp
, &tp
->suspend
.waitstatus
);
4721 scoped_restore_current_thread restore_thread
;
4722 switch_to_thread (tp
);
4724 if (target_stopped_by_watchpoint ())
4726 tp
->suspend
.stop_reason
4727 = TARGET_STOPPED_BY_WATCHPOINT
;
4729 else if (target_supports_stopped_by_sw_breakpoint ()
4730 && target_stopped_by_sw_breakpoint ())
4732 tp
->suspend
.stop_reason
4733 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4735 else if (target_supports_stopped_by_hw_breakpoint ()
4736 && target_stopped_by_hw_breakpoint ())
4738 tp
->suspend
.stop_reason
4739 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4741 else if (!target_supports_stopped_by_hw_breakpoint ()
4742 && hardware_breakpoint_inserted_here_p (aspace
,
4745 tp
->suspend
.stop_reason
4746 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4748 else if (!target_supports_stopped_by_sw_breakpoint ()
4749 && software_breakpoint_inserted_here_p (aspace
,
4752 tp
->suspend
.stop_reason
4753 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4755 else if (!thread_has_single_step_breakpoints_set (tp
)
4756 && currently_stepping (tp
))
4758 tp
->suspend
.stop_reason
4759 = TARGET_STOPPED_BY_SINGLE_STEP
;
4764 /* Mark the non-executing threads accordingly. In all-stop, all
4765 threads of all processes are stopped when we get any event
4766 reported. In non-stop mode, only the event thread stops. */
4769 mark_non_executing_threads (process_stratum_target
*target
,
4771 struct target_waitstatus ws
)
4775 if (!target_is_non_stop_p ())
4776 mark_ptid
= minus_one_ptid
;
4777 else if (ws
.kind
== TARGET_WAITKIND_SIGNALLED
4778 || ws
.kind
== TARGET_WAITKIND_EXITED
)
4780 /* If we're handling a process exit in non-stop mode, even
4781 though threads haven't been deleted yet, one would think
4782 that there is nothing to do, as threads of the dead process
4783 will be soon deleted, and threads of any other process were
4784 left running. However, on some targets, threads survive a
4785 process exit event. E.g., for the "checkpoint" command,
4786 when the current checkpoint/fork exits, linux-fork.c
4787 automatically switches to another fork from within
4788 target_mourn_inferior, by associating the same
4789 inferior/thread to another fork. We haven't mourned yet at
4790 this point, but we must mark any threads left in the
4791 process as not-executing so that finish_thread_state marks
4792 them stopped (in the user's perspective) if/when we present
4793 the stop to the user. */
4794 mark_ptid
= ptid_t (event_ptid
.pid ());
4797 mark_ptid
= event_ptid
;
4799 set_executing (target
, mark_ptid
, false);
4801 /* Likewise the resumed flag. */
4802 set_resumed (target
, mark_ptid
, false);
4805 /* Handle one event after stopping threads. If the eventing thread
4806 reports back any interesting event, we leave it pending. If the
4807 eventing thread was in the middle of a displaced step, we
4808 cancel/finish it, and unless the thread's inferior is being
4809 detached, put the thread back in the step-over chain. Returns true
4810 if there are no resumed threads left in the target (thus there's no
4811 point in waiting further), false otherwise. */
4814 handle_one (const wait_one_event
&event
)
4817 ("%s %s", target_waitstatus_to_string (&event
.ws
).c_str (),
4818 target_pid_to_str (event
.ptid
).c_str ());
4820 if (event
.ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4822 /* All resumed threads exited. */
4825 else if (event
.ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
4826 || event
.ws
.kind
== TARGET_WAITKIND_EXITED
4827 || event
.ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
4829 /* One thread/process exited/signalled. */
4831 thread_info
*t
= nullptr;
4833 /* The target may have reported just a pid. If so, try
4834 the first non-exited thread. */
4835 if (event
.ptid
.is_pid ())
4837 int pid
= event
.ptid
.pid ();
4838 inferior
*inf
= find_inferior_pid (event
.target
, pid
);
4839 for (thread_info
*tp
: inf
->non_exited_threads ())
4845 /* If there is no available thread, the event would
4846 have to be appended to a per-inferior event list,
4847 which does not exist (and if it did, we'd have
4848 to adjust run control command to be able to
4849 resume such an inferior). We assert here instead
4850 of going into an infinite loop. */
4851 gdb_assert (t
!= nullptr);
4854 ("using %s", target_pid_to_str (t
->ptid
).c_str ());
4858 t
= find_thread_ptid (event
.target
, event
.ptid
);
4859 /* Check if this is the first time we see this thread.
4860 Don't bother adding if it individually exited. */
4862 && event
.ws
.kind
!= TARGET_WAITKIND_THREAD_EXITED
)
4863 t
= add_thread (event
.target
, event
.ptid
);
4868 /* Set the threads as non-executing to avoid
4869 another stop attempt on them. */
4870 switch_to_thread_no_regs (t
);
4871 mark_non_executing_threads (event
.target
, event
.ptid
,
4873 save_waitstatus (t
, &event
.ws
);
4874 t
->stop_requested
= false;
4879 thread_info
*t
= find_thread_ptid (event
.target
, event
.ptid
);
4881 t
= add_thread (event
.target
, event
.ptid
);
4883 t
->stop_requested
= 0;
4886 t
->control
.may_range_step
= 0;
4888 /* This may be the first time we see the inferior report
4890 inferior
*inf
= find_inferior_ptid (event
.target
, event
.ptid
);
4891 if (inf
->needs_setup
)
4893 switch_to_thread_no_regs (t
);
4897 if (event
.ws
.kind
== TARGET_WAITKIND_STOPPED
4898 && event
.ws
.value
.sig
== GDB_SIGNAL_0
)
4900 /* We caught the event that we intended to catch, so
4901 there's no event pending. */
4902 t
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
4903 t
->suspend
.waitstatus_pending_p
= 0;
4905 if (displaced_step_finish (t
, GDB_SIGNAL_0
)
4906 == DISPLACED_STEP_FINISH_STATUS_NOT_EXECUTED
)
4908 /* Add it back to the step-over queue. */
4910 ("displaced-step of %s canceled",
4911 target_pid_to_str (t
->ptid
).c_str ());
4913 t
->control
.trap_expected
= 0;
4914 if (!t
->inf
->detaching
)
4915 global_thread_step_over_chain_enqueue (t
);
4920 enum gdb_signal sig
;
4921 struct regcache
*regcache
;
4924 ("target_wait %s, saving status for %d.%ld.%ld",
4925 target_waitstatus_to_string (&event
.ws
).c_str (),
4926 t
->ptid
.pid (), t
->ptid
.lwp (), t
->ptid
.tid ());
4928 /* Record for later. */
4929 save_waitstatus (t
, &event
.ws
);
4931 sig
= (event
.ws
.kind
== TARGET_WAITKIND_STOPPED
4932 ? event
.ws
.value
.sig
: GDB_SIGNAL_0
);
4934 if (displaced_step_finish (t
, sig
)
4935 == DISPLACED_STEP_FINISH_STATUS_NOT_EXECUTED
)
4937 /* Add it back to the step-over queue. */
4938 t
->control
.trap_expected
= 0;
4939 if (!t
->inf
->detaching
)
4940 global_thread_step_over_chain_enqueue (t
);
4943 regcache
= get_thread_regcache (t
);
4944 t
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4946 infrun_debug_printf ("saved stop_pc=%s for %s "
4947 "(currently_stepping=%d)",
4948 paddress (target_gdbarch (),
4949 t
->suspend
.stop_pc
),
4950 target_pid_to_str (t
->ptid
).c_str (),
4951 currently_stepping (t
));
4961 stop_all_threads (void)
4963 /* We may need multiple passes to discover all threads. */
4967 gdb_assert (exists_non_stop_target ());
4969 infrun_debug_printf ("starting");
4971 scoped_restore_current_thread restore_thread
;
4973 /* Enable thread events of all targets. */
4974 for (auto *target
: all_non_exited_process_targets ())
4976 switch_to_target_no_thread (target
);
4977 target_thread_events (true);
4982 /* Disable thread events of all targets. */
4983 for (auto *target
: all_non_exited_process_targets ())
4985 switch_to_target_no_thread (target
);
4986 target_thread_events (false);
4989 /* Use debug_prefixed_printf directly to get a meaningful function
4992 debug_prefixed_printf ("infrun", "stop_all_threads", "done");
4995 /* Request threads to stop, and then wait for the stops. Because
4996 threads we already know about can spawn more threads while we're
4997 trying to stop them, and we only learn about new threads when we
4998 update the thread list, do this in a loop, and keep iterating
4999 until two passes find no threads that need to be stopped. */
5000 for (pass
= 0; pass
< 2; pass
++, iterations
++)
5002 infrun_debug_printf ("pass=%d, iterations=%d", pass
, iterations
);
5005 int waits_needed
= 0;
5007 for (auto *target
: all_non_exited_process_targets ())
5009 switch_to_target_no_thread (target
);
5010 update_thread_list ();
5013 /* Go through all threads looking for threads that we need
5014 to tell the target to stop. */
5015 for (thread_info
*t
: all_non_exited_threads ())
5017 /* For a single-target setting with an all-stop target,
5018 we would not even arrive here. For a multi-target
5019 setting, until GDB is able to handle a mixture of
5020 all-stop and non-stop targets, simply skip all-stop
5021 targets' threads. This should be fine due to the
5022 protection of 'check_multi_target_resumption'. */
5024 switch_to_thread_no_regs (t
);
5025 if (!target_is_non_stop_p ())
5030 /* If already stopping, don't request a stop again.
5031 We just haven't seen the notification yet. */
5032 if (!t
->stop_requested
)
5034 infrun_debug_printf (" %s executing, need stop",
5035 target_pid_to_str (t
->ptid
).c_str ());
5036 target_stop (t
->ptid
);
5037 t
->stop_requested
= 1;
5041 infrun_debug_printf (" %s executing, already stopping",
5042 target_pid_to_str (t
->ptid
).c_str ());
5045 if (t
->stop_requested
)
5050 infrun_debug_printf (" %s not executing",
5051 target_pid_to_str (t
->ptid
).c_str ());
5053 /* The thread may be not executing, but still be
5054 resumed with a pending status to process. */
5059 if (waits_needed
== 0)
5062 /* If we find new threads on the second iteration, restart
5063 over. We want to see two iterations in a row with all
5068 for (int i
= 0; i
< waits_needed
; i
++)
5070 wait_one_event event
= wait_one ();
5071 if (handle_one (event
))
5078 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
5081 handle_no_resumed (struct execution_control_state
*ecs
)
5083 if (target_can_async_p ())
5085 bool any_sync
= false;
5087 for (ui
*ui
: all_uis ())
5089 if (ui
->prompt_state
== PROMPT_BLOCKED
)
5097 /* There were no unwaited-for children left in the target, but,
5098 we're not synchronously waiting for events either. Just
5101 infrun_debug_printf ("TARGET_WAITKIND_NO_RESUMED (ignoring: bg)");
5102 prepare_to_wait (ecs
);
5107 /* Otherwise, if we were running a synchronous execution command, we
5108 may need to cancel it and give the user back the terminal.
5110 In non-stop mode, the target can't tell whether we've already
5111 consumed previous stop events, so it can end up sending us a
5112 no-resumed event like so:
5114 #0 - thread 1 is left stopped
5116 #1 - thread 2 is resumed and hits breakpoint
5117 -> TARGET_WAITKIND_STOPPED
5119 #2 - thread 3 is resumed and exits
5120 this is the last resumed thread, so
5121 -> TARGET_WAITKIND_NO_RESUMED
5123 #3 - gdb processes stop for thread 2 and decides to re-resume
5126 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
5127 thread 2 is now resumed, so the event should be ignored.
5129 IOW, if the stop for thread 2 doesn't end a foreground command,
5130 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
5131 event. But it could be that the event meant that thread 2 itself
5132 (or whatever other thread was the last resumed thread) exited.
5134 To address this we refresh the thread list and check whether we
5135 have resumed threads _now_. In the example above, this removes
5136 thread 3 from the thread list. If thread 2 was re-resumed, we
5137 ignore this event. If we find no thread resumed, then we cancel
5138 the synchronous command and show "no unwaited-for " to the
5141 inferior
*curr_inf
= current_inferior ();
5143 scoped_restore_current_thread restore_thread
;
5145 for (auto *target
: all_non_exited_process_targets ())
5147 switch_to_target_no_thread (target
);
5148 update_thread_list ();
5153 - the current target has no thread executing, and
5154 - the current inferior is native, and
5155 - the current inferior is the one which has the terminal, and
5158 then a Ctrl-C from this point on would remain stuck in the
5159 kernel, until a thread resumes and dequeues it. That would
5160 result in the GDB CLI not reacting to Ctrl-C, not able to
5161 interrupt the program. To address this, if the current inferior
5162 no longer has any thread executing, we give the terminal to some
5163 other inferior that has at least one thread executing. */
5164 bool swap_terminal
= true;
5166 /* Whether to ignore this TARGET_WAITKIND_NO_RESUMED event, or
5167 whether to report it to the user. */
5168 bool ignore_event
= false;
5170 for (thread_info
*thread
: all_non_exited_threads ())
5172 if (swap_terminal
&& thread
->executing
)
5174 if (thread
->inf
!= curr_inf
)
5176 target_terminal::ours ();
5178 switch_to_thread (thread
);
5179 target_terminal::inferior ();
5181 swap_terminal
= false;
5185 && (thread
->executing
5186 || thread
->suspend
.waitstatus_pending_p
))
5188 /* Either there were no unwaited-for children left in the
5189 target at some point, but there are now, or some target
5190 other than the eventing one has unwaited-for children
5191 left. Just ignore. */
5192 infrun_debug_printf ("TARGET_WAITKIND_NO_RESUMED "
5193 "(ignoring: found resumed)");
5195 ignore_event
= true;
5198 if (ignore_event
&& !swap_terminal
)
5204 switch_to_inferior_no_thread (curr_inf
);
5205 prepare_to_wait (ecs
);
5209 /* Go ahead and report the event. */
5213 /* Given an execution control state that has been freshly filled in by
5214 an event from the inferior, figure out what it means and take
5217 The alternatives are:
5219 1) stop_waiting and return; to really stop and return to the
5222 2) keep_going and return; to wait for the next event (set
5223 ecs->event_thread->stepping_over_breakpoint to 1 to single step
5227 handle_inferior_event (struct execution_control_state
*ecs
)
5229 /* Make sure that all temporary struct value objects that were
5230 created during the handling of the event get deleted at the
5232 scoped_value_mark free_values
;
5234 infrun_debug_printf ("%s", target_waitstatus_to_string (&ecs
->ws
).c_str ());
5236 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
5238 /* We had an event in the inferior, but we are not interested in
5239 handling it at this level. The lower layers have already
5240 done what needs to be done, if anything.
5242 One of the possible circumstances for this is when the
5243 inferior produces output for the console. The inferior has
5244 not stopped, and we are ignoring the event. Another possible
5245 circumstance is any event which the lower level knows will be
5246 reported multiple times without an intervening resume. */
5247 prepare_to_wait (ecs
);
5251 if (ecs
->ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
)
5253 prepare_to_wait (ecs
);
5257 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
5258 && handle_no_resumed (ecs
))
5261 /* Cache the last target/ptid/waitstatus. */
5262 set_last_target_status (ecs
->target
, ecs
->ptid
, ecs
->ws
);
5264 /* Always clear state belonging to the previous time we stopped. */
5265 stop_stack_dummy
= STOP_NONE
;
5267 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
5269 /* No unwaited-for children left. IOW, all resumed children
5271 stop_print_frame
= false;
5276 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
5277 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
5279 ecs
->event_thread
= find_thread_ptid (ecs
->target
, ecs
->ptid
);
5280 /* If it's a new thread, add it to the thread database. */
5281 if (ecs
->event_thread
== NULL
)
5282 ecs
->event_thread
= add_thread (ecs
->target
, ecs
->ptid
);
5284 /* Disable range stepping. If the next step request could use a
5285 range, this will be end up re-enabled then. */
5286 ecs
->event_thread
->control
.may_range_step
= 0;
5289 /* Dependent on valid ECS->EVENT_THREAD. */
5290 adjust_pc_after_break (ecs
->event_thread
, &ecs
->ws
);
5292 /* Dependent on the current PC value modified by adjust_pc_after_break. */
5293 reinit_frame_cache ();
5295 breakpoint_retire_moribund ();
5297 /* First, distinguish signals caused by the debugger from signals
5298 that have to do with the program's own actions. Note that
5299 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
5300 on the operating system version. Here we detect when a SIGILL or
5301 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
5302 something similar for SIGSEGV, since a SIGSEGV will be generated
5303 when we're trying to execute a breakpoint instruction on a
5304 non-executable stack. This happens for call dummy breakpoints
5305 for architectures like SPARC that place call dummies on the
5307 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
5308 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
5309 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
5310 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
5312 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
5314 if (breakpoint_inserted_here_p (regcache
->aspace (),
5315 regcache_read_pc (regcache
)))
5317 infrun_debug_printf ("Treating signal as SIGTRAP");
5318 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
5322 mark_non_executing_threads (ecs
->target
, ecs
->ptid
, ecs
->ws
);
5324 switch (ecs
->ws
.kind
)
5326 case TARGET_WAITKIND_LOADED
:
5328 context_switch (ecs
);
5329 /* Ignore gracefully during startup of the inferior, as it might
5330 be the shell which has just loaded some objects, otherwise
5331 add the symbols for the newly loaded objects. Also ignore at
5332 the beginning of an attach or remote session; we will query
5333 the full list of libraries once the connection is
5336 stop_kind stop_soon
= get_inferior_stop_soon (ecs
);
5337 if (stop_soon
== NO_STOP_QUIETLY
)
5339 struct regcache
*regcache
;
5341 regcache
= get_thread_regcache (ecs
->event_thread
);
5343 handle_solib_event ();
5345 ecs
->event_thread
->control
.stop_bpstat
5346 = bpstat_stop_status (regcache
->aspace (),
5347 ecs
->event_thread
->suspend
.stop_pc
,
5348 ecs
->event_thread
, &ecs
->ws
);
5350 if (handle_stop_requested (ecs
))
5353 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5355 /* A catchpoint triggered. */
5356 process_event_stop_test (ecs
);
5360 /* If requested, stop when the dynamic linker notifies
5361 gdb of events. This allows the user to get control
5362 and place breakpoints in initializer routines for
5363 dynamically loaded objects (among other things). */
5364 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5365 if (stop_on_solib_events
)
5367 /* Make sure we print "Stopped due to solib-event" in
5369 stop_print_frame
= true;
5376 /* If we are skipping through a shell, or through shared library
5377 loading that we aren't interested in, resume the program. If
5378 we're running the program normally, also resume. */
5379 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
5381 /* Loading of shared libraries might have changed breakpoint
5382 addresses. Make sure new breakpoints are inserted. */
5383 if (stop_soon
== NO_STOP_QUIETLY
)
5384 insert_breakpoints ();
5385 resume (GDB_SIGNAL_0
);
5386 prepare_to_wait (ecs
);
5390 /* But stop if we're attaching or setting up a remote
5392 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5393 || stop_soon
== STOP_QUIETLY_REMOTE
)
5395 infrun_debug_printf ("quietly stopped");
5400 internal_error (__FILE__
, __LINE__
,
5401 _("unhandled stop_soon: %d"), (int) stop_soon
);
5404 case TARGET_WAITKIND_SPURIOUS
:
5405 if (handle_stop_requested (ecs
))
5407 context_switch (ecs
);
5408 resume (GDB_SIGNAL_0
);
5409 prepare_to_wait (ecs
);
5412 case TARGET_WAITKIND_THREAD_CREATED
:
5413 if (handle_stop_requested (ecs
))
5415 context_switch (ecs
);
5416 if (!switch_back_to_stepped_thread (ecs
))
5420 case TARGET_WAITKIND_EXITED
:
5421 case TARGET_WAITKIND_SIGNALLED
:
5423 /* Depending on the system, ecs->ptid may point to a thread or
5424 to a process. On some targets, target_mourn_inferior may
5425 need to have access to the just-exited thread. That is the
5426 case of GNU/Linux's "checkpoint" support, for example.
5427 Call the switch_to_xxx routine as appropriate. */
5428 thread_info
*thr
= find_thread_ptid (ecs
->target
, ecs
->ptid
);
5430 switch_to_thread (thr
);
5433 inferior
*inf
= find_inferior_ptid (ecs
->target
, ecs
->ptid
);
5434 switch_to_inferior_no_thread (inf
);
5437 handle_vfork_child_exec_or_exit (0);
5438 target_terminal::ours (); /* Must do this before mourn anyway. */
5440 /* Clearing any previous state of convenience variables. */
5441 clear_exit_convenience_vars ();
5443 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5445 /* Record the exit code in the convenience variable $_exitcode, so
5446 that the user can inspect this again later. */
5447 set_internalvar_integer (lookup_internalvar ("_exitcode"),
5448 (LONGEST
) ecs
->ws
.value
.integer
);
5450 /* Also record this in the inferior itself. */
5451 current_inferior ()->has_exit_code
= 1;
5452 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
5454 /* Support the --return-child-result option. */
5455 return_child_result_value
= ecs
->ws
.value
.integer
;
5457 gdb::observers::exited
.notify (ecs
->ws
.value
.integer
);
5461 struct gdbarch
*gdbarch
= current_inferior ()->gdbarch
;
5463 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
5465 /* Set the value of the internal variable $_exitsignal,
5466 which holds the signal uncaught by the inferior. */
5467 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
5468 gdbarch_gdb_signal_to_target (gdbarch
,
5469 ecs
->ws
.value
.sig
));
5473 /* We don't have access to the target's method used for
5474 converting between signal numbers (GDB's internal
5475 representation <-> target's representation).
5476 Therefore, we cannot do a good job at displaying this
5477 information to the user. It's better to just warn
5478 her about it (if infrun debugging is enabled), and
5480 infrun_debug_printf ("Cannot fill $_exitsignal with the correct "
5484 gdb::observers::signal_exited
.notify (ecs
->ws
.value
.sig
);
5487 gdb_flush (gdb_stdout
);
5488 target_mourn_inferior (inferior_ptid
);
5489 stop_print_frame
= false;
5493 case TARGET_WAITKIND_FORKED
:
5494 case TARGET_WAITKIND_VFORKED
:
5495 /* Check whether the inferior is displaced stepping. */
5497 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
5498 struct gdbarch
*gdbarch
= regcache
->arch ();
5499 inferior
*parent_inf
= find_inferior_ptid (ecs
->target
, ecs
->ptid
);
5501 /* If this is a fork (child gets its own address space copy)
5502 and some displaced step buffers were in use at the time of
5503 the fork, restore the displaced step buffer bytes in the
5506 Architectures which support displaced stepping and fork
5507 events must supply an implementation of
5508 gdbarch_displaced_step_restore_all_in_ptid. This is not
5509 enforced during gdbarch validation to support architectures
5510 which support displaced stepping but not forks. */
5511 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
5512 && gdbarch_supports_displaced_stepping (gdbarch
))
5513 gdbarch_displaced_step_restore_all_in_ptid
5514 (gdbarch
, parent_inf
, ecs
->ws
.value
.related_pid
);
5516 /* If displaced stepping is supported, and thread ecs->ptid is
5517 displaced stepping. */
5518 if (displaced_step_in_progress_thread (ecs
->event_thread
))
5520 struct regcache
*child_regcache
;
5521 CORE_ADDR parent_pc
;
5523 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
5524 indicating that the displaced stepping of syscall instruction
5525 has been done. Perform cleanup for parent process here. Note
5526 that this operation also cleans up the child process for vfork,
5527 because their pages are shared. */
5528 displaced_step_finish (ecs
->event_thread
, GDB_SIGNAL_TRAP
);
5529 /* Start a new step-over in another thread if there's one
5533 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
5534 the child's PC is also within the scratchpad. Set the child's PC
5535 to the parent's PC value, which has already been fixed up.
5536 FIXME: we use the parent's aspace here, although we're touching
5537 the child, because the child hasn't been added to the inferior
5538 list yet at this point. */
5541 = get_thread_arch_aspace_regcache (parent_inf
->process_target (),
5542 ecs
->ws
.value
.related_pid
,
5544 parent_inf
->aspace
);
5545 /* Read PC value of parent process. */
5546 parent_pc
= regcache_read_pc (regcache
);
5548 displaced_debug_printf ("write child pc from %s to %s",
5550 regcache_read_pc (child_regcache
)),
5551 paddress (gdbarch
, parent_pc
));
5553 regcache_write_pc (child_regcache
, parent_pc
);
5557 context_switch (ecs
);
5559 /* Immediately detach breakpoints from the child before there's
5560 any chance of letting the user delete breakpoints from the
5561 breakpoint lists. If we don't do this early, it's easy to
5562 leave left over traps in the child, vis: "break foo; catch
5563 fork; c; <fork>; del; c; <child calls foo>". We only follow
5564 the fork on the last `continue', and by that time the
5565 breakpoint at "foo" is long gone from the breakpoint table.
5566 If we vforked, then we don't need to unpatch here, since both
5567 parent and child are sharing the same memory pages; we'll
5568 need to unpatch at follow/detach time instead to be certain
5569 that new breakpoints added between catchpoint hit time and
5570 vfork follow are detached. */
5571 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
5573 /* This won't actually modify the breakpoint list, but will
5574 physically remove the breakpoints from the child. */
5575 detach_breakpoints (ecs
->ws
.value
.related_pid
);
5578 delete_just_stopped_threads_single_step_breakpoints ();
5580 /* In case the event is caught by a catchpoint, remember that
5581 the event is to be followed at the next resume of the thread,
5582 and not immediately. */
5583 ecs
->event_thread
->pending_follow
= ecs
->ws
;
5585 ecs
->event_thread
->suspend
.stop_pc
5586 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
5588 ecs
->event_thread
->control
.stop_bpstat
5589 = bpstat_stop_status (get_current_regcache ()->aspace (),
5590 ecs
->event_thread
->suspend
.stop_pc
,
5591 ecs
->event_thread
, &ecs
->ws
);
5593 if (handle_stop_requested (ecs
))
5596 /* If no catchpoint triggered for this, then keep going. Note
5597 that we're interested in knowing the bpstat actually causes a
5598 stop, not just if it may explain the signal. Software
5599 watchpoints, for example, always appear in the bpstat. */
5600 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5603 = (follow_fork_mode_string
== follow_fork_mode_child
);
5605 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5607 process_stratum_target
*targ
5608 = ecs
->event_thread
->inf
->process_target ();
5610 bool should_resume
= follow_fork ();
5612 /* Note that one of these may be an invalid pointer,
5613 depending on detach_fork. */
5614 thread_info
*parent
= ecs
->event_thread
;
5616 = find_thread_ptid (targ
, ecs
->ws
.value
.related_pid
);
5618 /* At this point, the parent is marked running, and the
5619 child is marked stopped. */
5621 /* If not resuming the parent, mark it stopped. */
5622 if (follow_child
&& !detach_fork
&& !non_stop
&& !sched_multi
)
5623 parent
->set_running (false);
5625 /* If resuming the child, mark it running. */
5626 if (follow_child
|| (!detach_fork
&& (non_stop
|| sched_multi
)))
5627 child
->set_running (true);
5629 /* In non-stop mode, also resume the other branch. */
5630 if (!detach_fork
&& (non_stop
5631 || (sched_multi
&& target_is_non_stop_p ())))
5634 switch_to_thread (parent
);
5636 switch_to_thread (child
);
5638 ecs
->event_thread
= inferior_thread ();
5639 ecs
->ptid
= inferior_ptid
;
5644 switch_to_thread (child
);
5646 switch_to_thread (parent
);
5648 ecs
->event_thread
= inferior_thread ();
5649 ecs
->ptid
= inferior_ptid
;
5657 process_event_stop_test (ecs
);
5660 case TARGET_WAITKIND_VFORK_DONE
:
5661 /* Done with the shared memory region. Re-insert breakpoints in
5662 the parent, and keep going. */
5664 context_switch (ecs
);
5666 current_inferior ()->waiting_for_vfork_done
= 0;
5667 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
5669 if (handle_stop_requested (ecs
))
5672 /* This also takes care of reinserting breakpoints in the
5673 previously locked inferior. */
5677 case TARGET_WAITKIND_EXECD
:
5679 /* Note we can't read registers yet (the stop_pc), because we
5680 don't yet know the inferior's post-exec architecture.
5681 'stop_pc' is explicitly read below instead. */
5682 switch_to_thread_no_regs (ecs
->event_thread
);
5684 /* Do whatever is necessary to the parent branch of the vfork. */
5685 handle_vfork_child_exec_or_exit (1);
5687 /* This causes the eventpoints and symbol table to be reset.
5688 Must do this now, before trying to determine whether to
5690 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
5692 /* In follow_exec we may have deleted the original thread and
5693 created a new one. Make sure that the event thread is the
5694 execd thread for that case (this is a nop otherwise). */
5695 ecs
->event_thread
= inferior_thread ();
5697 ecs
->event_thread
->suspend
.stop_pc
5698 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
5700 ecs
->event_thread
->control
.stop_bpstat
5701 = bpstat_stop_status (get_current_regcache ()->aspace (),
5702 ecs
->event_thread
->suspend
.stop_pc
,
5703 ecs
->event_thread
, &ecs
->ws
);
5705 /* Note that this may be referenced from inside
5706 bpstat_stop_status above, through inferior_has_execd. */
5707 xfree (ecs
->ws
.value
.execd_pathname
);
5708 ecs
->ws
.value
.execd_pathname
= NULL
;
5710 if (handle_stop_requested (ecs
))
5713 /* If no catchpoint triggered for this, then keep going. */
5714 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5716 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5720 process_event_stop_test (ecs
);
5723 /* Be careful not to try to gather much state about a thread
5724 that's in a syscall. It's frequently a losing proposition. */
5725 case TARGET_WAITKIND_SYSCALL_ENTRY
:
5726 /* Getting the current syscall number. */
5727 if (handle_syscall_event (ecs
) == 0)
5728 process_event_stop_test (ecs
);
5731 /* Before examining the threads further, step this thread to
5732 get it entirely out of the syscall. (We get notice of the
5733 event when the thread is just on the verge of exiting a
5734 syscall. Stepping one instruction seems to get it back
5736 case TARGET_WAITKIND_SYSCALL_RETURN
:
5737 if (handle_syscall_event (ecs
) == 0)
5738 process_event_stop_test (ecs
);
5741 case TARGET_WAITKIND_STOPPED
:
5742 handle_signal_stop (ecs
);
5745 case TARGET_WAITKIND_NO_HISTORY
:
5746 /* Reverse execution: target ran out of history info. */
5748 /* Switch to the stopped thread. */
5749 context_switch (ecs
);
5750 infrun_debug_printf ("stopped");
5752 delete_just_stopped_threads_single_step_breakpoints ();
5753 ecs
->event_thread
->suspend
.stop_pc
5754 = regcache_read_pc (get_thread_regcache (inferior_thread ()));
5756 if (handle_stop_requested (ecs
))
5759 gdb::observers::no_history
.notify ();
5765 /* Restart threads back to what they were trying to do back when we
5766 paused them for an in-line step-over. The EVENT_THREAD thread is
5770 restart_threads (struct thread_info
*event_thread
)
5772 /* In case the instruction just stepped spawned a new thread. */
5773 update_thread_list ();
5775 for (thread_info
*tp
: all_non_exited_threads ())
5777 if (tp
->inf
->detaching
)
5779 infrun_debug_printf ("restart threads: [%s] inferior detaching",
5780 target_pid_to_str (tp
->ptid
).c_str ());
5784 switch_to_thread_no_regs (tp
);
5786 if (tp
== event_thread
)
5788 infrun_debug_printf ("restart threads: [%s] is event thread",
5789 target_pid_to_str (tp
->ptid
).c_str ());
5793 if (!(tp
->state
== THREAD_RUNNING
|| tp
->control
.in_infcall
))
5795 infrun_debug_printf ("restart threads: [%s] not meant to be running",
5796 target_pid_to_str (tp
->ptid
).c_str ());
5802 infrun_debug_printf ("restart threads: [%s] resumed",
5803 target_pid_to_str (tp
->ptid
).c_str ());
5804 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
5808 if (thread_is_in_step_over_chain (tp
))
5810 infrun_debug_printf ("restart threads: [%s] needs step-over",
5811 target_pid_to_str (tp
->ptid
).c_str ());
5812 gdb_assert (!tp
->resumed
);
5817 if (tp
->suspend
.waitstatus_pending_p
)
5819 infrun_debug_printf ("restart threads: [%s] has pending status",
5820 target_pid_to_str (tp
->ptid
).c_str ());
5825 gdb_assert (!tp
->stop_requested
);
5827 /* If some thread needs to start a step-over at this point, it
5828 should still be in the step-over queue, and thus skipped
5830 if (thread_still_needs_step_over (tp
))
5832 internal_error (__FILE__
, __LINE__
,
5833 "thread [%s] needs a step-over, but not in "
5834 "step-over queue\n",
5835 target_pid_to_str (tp
->ptid
).c_str ());
5838 if (currently_stepping (tp
))
5840 infrun_debug_printf ("restart threads: [%s] was stepping",
5841 target_pid_to_str (tp
->ptid
).c_str ());
5842 keep_going_stepped_thread (tp
);
5846 struct execution_control_state ecss
;
5847 struct execution_control_state
*ecs
= &ecss
;
5849 infrun_debug_printf ("restart threads: [%s] continuing",
5850 target_pid_to_str (tp
->ptid
).c_str ());
5851 reset_ecs (ecs
, tp
);
5852 switch_to_thread (tp
);
5853 keep_going_pass_signal (ecs
);
5858 /* Callback for iterate_over_threads. Find a resumed thread that has
5859 a pending waitstatus. */
5862 resumed_thread_with_pending_status (struct thread_info
*tp
,
5866 && tp
->suspend
.waitstatus_pending_p
);
5869 /* Called when we get an event that may finish an in-line or
5870 out-of-line (displaced stepping) step-over started previously.
5871 Return true if the event is processed and we should go back to the
5872 event loop; false if the caller should continue processing the
5876 finish_step_over (struct execution_control_state
*ecs
)
5878 displaced_step_finish (ecs
->event_thread
,
5879 ecs
->event_thread
->suspend
.stop_signal
);
5881 bool had_step_over_info
= step_over_info_valid_p ();
5883 if (had_step_over_info
)
5885 /* If we're stepping over a breakpoint with all threads locked,
5886 then only the thread that was stepped should be reporting
5888 gdb_assert (ecs
->event_thread
->control
.trap_expected
);
5890 clear_step_over_info ();
5893 if (!target_is_non_stop_p ())
5896 /* Start a new step-over in another thread if there's one that
5900 /* If we were stepping over a breakpoint before, and haven't started
5901 a new in-line step-over sequence, then restart all other threads
5902 (except the event thread). We can't do this in all-stop, as then
5903 e.g., we wouldn't be able to issue any other remote packet until
5904 these other threads stop. */
5905 if (had_step_over_info
&& !step_over_info_valid_p ())
5907 struct thread_info
*pending
;
5909 /* If we only have threads with pending statuses, the restart
5910 below won't restart any thread and so nothing re-inserts the
5911 breakpoint we just stepped over. But we need it inserted
5912 when we later process the pending events, otherwise if
5913 another thread has a pending event for this breakpoint too,
5914 we'd discard its event (because the breakpoint that
5915 originally caused the event was no longer inserted). */
5916 context_switch (ecs
);
5917 insert_breakpoints ();
5919 restart_threads (ecs
->event_thread
);
5921 /* If we have events pending, go through handle_inferior_event
5922 again, picking up a pending event at random. This avoids
5923 thread starvation. */
5925 /* But not if we just stepped over a watchpoint in order to let
5926 the instruction execute so we can evaluate its expression.
5927 The set of watchpoints that triggered is recorded in the
5928 breakpoint objects themselves (see bp->watchpoint_triggered).
5929 If we processed another event first, that other event could
5930 clobber this info. */
5931 if (ecs
->event_thread
->stepping_over_watchpoint
)
5934 pending
= iterate_over_threads (resumed_thread_with_pending_status
,
5936 if (pending
!= NULL
)
5938 struct thread_info
*tp
= ecs
->event_thread
;
5939 struct regcache
*regcache
;
5941 infrun_debug_printf ("found resumed threads with "
5942 "pending events, saving status");
5944 gdb_assert (pending
!= tp
);
5946 /* Record the event thread's event for later. */
5947 save_waitstatus (tp
, &ecs
->ws
);
5948 /* This was cleared early, by handle_inferior_event. Set it
5949 so this pending event is considered by
5953 gdb_assert (!tp
->executing
);
5955 regcache
= get_thread_regcache (tp
);
5956 tp
->suspend
.stop_pc
= regcache_read_pc (regcache
);
5958 infrun_debug_printf ("saved stop_pc=%s for %s "
5959 "(currently_stepping=%d)",
5960 paddress (target_gdbarch (),
5961 tp
->suspend
.stop_pc
),
5962 target_pid_to_str (tp
->ptid
).c_str (),
5963 currently_stepping (tp
));
5965 /* This in-line step-over finished; clear this so we won't
5966 start a new one. This is what handle_signal_stop would
5967 do, if we returned false. */
5968 tp
->stepping_over_breakpoint
= 0;
5970 /* Wake up the event loop again. */
5971 mark_async_event_handler (infrun_async_inferior_event_token
);
5973 prepare_to_wait (ecs
);
5981 /* Come here when the program has stopped with a signal. */
5984 handle_signal_stop (struct execution_control_state
*ecs
)
5986 struct frame_info
*frame
;
5987 struct gdbarch
*gdbarch
;
5988 int stopped_by_watchpoint
;
5989 enum stop_kind stop_soon
;
5992 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
5994 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
5996 /* Do we need to clean up the state of a thread that has
5997 completed a displaced single-step? (Doing so usually affects
5998 the PC, so do it here, before we set stop_pc.) */
5999 if (finish_step_over (ecs
))
6002 /* If we either finished a single-step or hit a breakpoint, but
6003 the user wanted this thread to be stopped, pretend we got a
6004 SIG0 (generic unsignaled stop). */
6005 if (ecs
->event_thread
->stop_requested
6006 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
6007 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6009 ecs
->event_thread
->suspend
.stop_pc
6010 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
6012 context_switch (ecs
);
6014 if (deprecated_context_hook
)
6015 deprecated_context_hook (ecs
->event_thread
->global_num
);
6019 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
6020 struct gdbarch
*reg_gdbarch
= regcache
->arch ();
6022 infrun_debug_printf ("stop_pc=%s",
6023 paddress (reg_gdbarch
,
6024 ecs
->event_thread
->suspend
.stop_pc
));
6025 if (target_stopped_by_watchpoint ())
6029 infrun_debug_printf ("stopped by watchpoint");
6031 if (target_stopped_data_address (current_inferior ()->top_target (),
6033 infrun_debug_printf ("stopped data address=%s",
6034 paddress (reg_gdbarch
, addr
));
6036 infrun_debug_printf ("(no data address available)");
6040 /* This is originated from start_remote(), start_inferior() and
6041 shared libraries hook functions. */
6042 stop_soon
= get_inferior_stop_soon (ecs
);
6043 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
6045 infrun_debug_printf ("quietly stopped");
6046 stop_print_frame
= true;
6051 /* This originates from attach_command(). We need to overwrite
6052 the stop_signal here, because some kernels don't ignore a
6053 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
6054 See more comments in inferior.h. On the other hand, if we
6055 get a non-SIGSTOP, report it to the user - assume the backend
6056 will handle the SIGSTOP if it should show up later.
6058 Also consider that the attach is complete when we see a
6059 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
6060 target extended-remote report it instead of a SIGSTOP
6061 (e.g. gdbserver). We already rely on SIGTRAP being our
6062 signal, so this is no exception.
6064 Also consider that the attach is complete when we see a
6065 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
6066 the target to stop all threads of the inferior, in case the
6067 low level attach operation doesn't stop them implicitly. If
6068 they weren't stopped implicitly, then the stub will report a
6069 GDB_SIGNAL_0, meaning: stopped for no particular reason
6070 other than GDB's request. */
6071 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
6072 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
6073 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6074 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
6076 stop_print_frame
= true;
6078 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6082 /* At this point, get hold of the now-current thread's frame. */
6083 frame
= get_current_frame ();
6084 gdbarch
= get_frame_arch (frame
);
6086 /* Pull the single step breakpoints out of the target. */
6087 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
6089 struct regcache
*regcache
;
6092 regcache
= get_thread_regcache (ecs
->event_thread
);
6093 const address_space
*aspace
= regcache
->aspace ();
6095 pc
= regcache_read_pc (regcache
);
6097 /* However, before doing so, if this single-step breakpoint was
6098 actually for another thread, set this thread up for moving
6100 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
6103 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
6105 infrun_debug_printf ("[%s] hit another thread's single-step "
6107 target_pid_to_str (ecs
->ptid
).c_str ());
6108 ecs
->hit_singlestep_breakpoint
= 1;
6113 infrun_debug_printf ("[%s] hit its single-step breakpoint",
6114 target_pid_to_str (ecs
->ptid
).c_str ());
6117 delete_just_stopped_threads_single_step_breakpoints ();
6119 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6120 && ecs
->event_thread
->control
.trap_expected
6121 && ecs
->event_thread
->stepping_over_watchpoint
)
6122 stopped_by_watchpoint
= 0;
6124 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
6126 /* If necessary, step over this watchpoint. We'll be back to display
6128 if (stopped_by_watchpoint
6129 && (target_have_steppable_watchpoint ()
6130 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
6132 /* At this point, we are stopped at an instruction which has
6133 attempted to write to a piece of memory under control of
6134 a watchpoint. The instruction hasn't actually executed
6135 yet. If we were to evaluate the watchpoint expression
6136 now, we would get the old value, and therefore no change
6137 would seem to have occurred.
6139 In order to make watchpoints work `right', we really need
6140 to complete the memory write, and then evaluate the
6141 watchpoint expression. We do this by single-stepping the
6144 It may not be necessary to disable the watchpoint to step over
6145 it. For example, the PA can (with some kernel cooperation)
6146 single step over a watchpoint without disabling the watchpoint.
6148 It is far more common to need to disable a watchpoint to step
6149 the inferior over it. If we have non-steppable watchpoints,
6150 we must disable the current watchpoint; it's simplest to
6151 disable all watchpoints.
6153 Any breakpoint at PC must also be stepped over -- if there's
6154 one, it will have already triggered before the watchpoint
6155 triggered, and we either already reported it to the user, or
6156 it didn't cause a stop and we called keep_going. In either
6157 case, if there was a breakpoint at PC, we must be trying to
6159 ecs
->event_thread
->stepping_over_watchpoint
= 1;
6164 ecs
->event_thread
->stepping_over_breakpoint
= 0;
6165 ecs
->event_thread
->stepping_over_watchpoint
= 0;
6166 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
6167 ecs
->event_thread
->control
.stop_step
= 0;
6168 stop_print_frame
= true;
6169 stopped_by_random_signal
= 0;
6170 bpstat stop_chain
= NULL
;
6172 /* Hide inlined functions starting here, unless we just performed stepi or
6173 nexti. After stepi and nexti, always show the innermost frame (not any
6174 inline function call sites). */
6175 if (ecs
->event_thread
->control
.step_range_end
!= 1)
6177 const address_space
*aspace
6178 = get_thread_regcache (ecs
->event_thread
)->aspace ();
6180 /* skip_inline_frames is expensive, so we avoid it if we can
6181 determine that the address is one where functions cannot have
6182 been inlined. This improves performance with inferiors that
6183 load a lot of shared libraries, because the solib event
6184 breakpoint is defined as the address of a function (i.e. not
6185 inline). Note that we have to check the previous PC as well
6186 as the current one to catch cases when we have just
6187 single-stepped off a breakpoint prior to reinstating it.
6188 Note that we're assuming that the code we single-step to is
6189 not inline, but that's not definitive: there's nothing
6190 preventing the event breakpoint function from containing
6191 inlined code, and the single-step ending up there. If the
6192 user had set a breakpoint on that inlined code, the missing
6193 skip_inline_frames call would break things. Fortunately
6194 that's an extremely unlikely scenario. */
6195 if (!pc_at_non_inline_function (aspace
,
6196 ecs
->event_thread
->suspend
.stop_pc
,
6198 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6199 && ecs
->event_thread
->control
.trap_expected
6200 && pc_at_non_inline_function (aspace
,
6201 ecs
->event_thread
->prev_pc
,
6204 stop_chain
= build_bpstat_chain (aspace
,
6205 ecs
->event_thread
->suspend
.stop_pc
,
6207 skip_inline_frames (ecs
->event_thread
, stop_chain
);
6209 /* Re-fetch current thread's frame in case that invalidated
6211 frame
= get_current_frame ();
6212 gdbarch
= get_frame_arch (frame
);
6216 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6217 && ecs
->event_thread
->control
.trap_expected
6218 && gdbarch_single_step_through_delay_p (gdbarch
)
6219 && currently_stepping (ecs
->event_thread
))
6221 /* We're trying to step off a breakpoint. Turns out that we're
6222 also on an instruction that needs to be stepped multiple
6223 times before it's been fully executing. E.g., architectures
6224 with a delay slot. It needs to be stepped twice, once for
6225 the instruction and once for the delay slot. */
6226 int step_through_delay
6227 = gdbarch_single_step_through_delay (gdbarch
, frame
);
6229 if (step_through_delay
)
6230 infrun_debug_printf ("step through delay");
6232 if (ecs
->event_thread
->control
.step_range_end
== 0
6233 && step_through_delay
)
6235 /* The user issued a continue when stopped at a breakpoint.
6236 Set up for another trap and get out of here. */
6237 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6241 else if (step_through_delay
)
6243 /* The user issued a step when stopped at a breakpoint.
6244 Maybe we should stop, maybe we should not - the delay
6245 slot *might* correspond to a line of source. In any
6246 case, don't decide that here, just set
6247 ecs->stepping_over_breakpoint, making sure we
6248 single-step again before breakpoints are re-inserted. */
6249 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6253 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
6254 handles this event. */
6255 ecs
->event_thread
->control
.stop_bpstat
6256 = bpstat_stop_status (get_current_regcache ()->aspace (),
6257 ecs
->event_thread
->suspend
.stop_pc
,
6258 ecs
->event_thread
, &ecs
->ws
, stop_chain
);
6260 /* Following in case break condition called a
6262 stop_print_frame
= true;
6264 /* This is where we handle "moribund" watchpoints. Unlike
6265 software breakpoints traps, hardware watchpoint traps are
6266 always distinguishable from random traps. If no high-level
6267 watchpoint is associated with the reported stop data address
6268 anymore, then the bpstat does not explain the signal ---
6269 simply make sure to ignore it if `stopped_by_watchpoint' is
6272 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6273 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
6275 && stopped_by_watchpoint
)
6277 infrun_debug_printf ("no user watchpoint explains watchpoint SIGTRAP, "
6281 /* NOTE: cagney/2003-03-29: These checks for a random signal
6282 at one stage in the past included checks for an inferior
6283 function call's call dummy's return breakpoint. The original
6284 comment, that went with the test, read:
6286 ``End of a stack dummy. Some systems (e.g. Sony news) give
6287 another signal besides SIGTRAP, so check here as well as
6290 If someone ever tries to get call dummys on a
6291 non-executable stack to work (where the target would stop
6292 with something like a SIGSEGV), then those tests might need
6293 to be re-instated. Given, however, that the tests were only
6294 enabled when momentary breakpoints were not being used, I
6295 suspect that it won't be the case.
6297 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
6298 be necessary for call dummies on a non-executable stack on
6301 /* See if the breakpoints module can explain the signal. */
6303 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
6304 ecs
->event_thread
->suspend
.stop_signal
);
6306 /* Maybe this was a trap for a software breakpoint that has since
6308 if (random_signal
&& target_stopped_by_sw_breakpoint ())
6310 if (gdbarch_program_breakpoint_here_p (gdbarch
,
6311 ecs
->event_thread
->suspend
.stop_pc
))
6313 struct regcache
*regcache
;
6316 /* Re-adjust PC to what the program would see if GDB was not
6318 regcache
= get_thread_regcache (ecs
->event_thread
);
6319 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
6322 gdb::optional
<scoped_restore_tmpl
<int>>
6323 restore_operation_disable
;
6325 if (record_full_is_used ())
6326 restore_operation_disable
.emplace
6327 (record_full_gdb_operation_disable_set ());
6329 regcache_write_pc (regcache
,
6330 ecs
->event_thread
->suspend
.stop_pc
+ decr_pc
);
6335 /* A delayed software breakpoint event. Ignore the trap. */
6336 infrun_debug_printf ("delayed software breakpoint trap, ignoring");
6341 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
6342 has since been removed. */
6343 if (random_signal
&& target_stopped_by_hw_breakpoint ())
6345 /* A delayed hardware breakpoint event. Ignore the trap. */
6346 infrun_debug_printf ("delayed hardware breakpoint/watchpoint "
6351 /* If not, perhaps stepping/nexting can. */
6353 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6354 && currently_stepping (ecs
->event_thread
));
6356 /* Perhaps the thread hit a single-step breakpoint of _another_
6357 thread. Single-step breakpoints are transparent to the
6358 breakpoints module. */
6360 random_signal
= !ecs
->hit_singlestep_breakpoint
;
6362 /* No? Perhaps we got a moribund watchpoint. */
6364 random_signal
= !stopped_by_watchpoint
;
6366 /* Always stop if the user explicitly requested this thread to
6368 if (ecs
->event_thread
->stop_requested
)
6371 infrun_debug_printf ("user-requested stop");
6374 /* For the program's own signals, act according to
6375 the signal handling tables. */
6379 /* Signal not for debugging purposes. */
6380 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
6382 infrun_debug_printf ("random signal (%s)",
6383 gdb_signal_to_symbol_string (stop_signal
));
6385 stopped_by_random_signal
= 1;
6387 /* Always stop on signals if we're either just gaining control
6388 of the program, or the user explicitly requested this thread
6389 to remain stopped. */
6390 if (stop_soon
!= NO_STOP_QUIETLY
6391 || ecs
->event_thread
->stop_requested
6392 || signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
))
6398 /* Notify observers the signal has "handle print" set. Note we
6399 returned early above if stopping; normal_stop handles the
6400 printing in that case. */
6401 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
6403 /* The signal table tells us to print about this signal. */
6404 target_terminal::ours_for_output ();
6405 gdb::observers::signal_received
.notify (ecs
->event_thread
->suspend
.stop_signal
);
6406 target_terminal::inferior ();
6409 /* Clear the signal if it should not be passed. */
6410 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
6411 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6413 if (ecs
->event_thread
->prev_pc
== ecs
->event_thread
->suspend
.stop_pc
6414 && ecs
->event_thread
->control
.trap_expected
6415 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6417 /* We were just starting a new sequence, attempting to
6418 single-step off of a breakpoint and expecting a SIGTRAP.
6419 Instead this signal arrives. This signal will take us out
6420 of the stepping range so GDB needs to remember to, when
6421 the signal handler returns, resume stepping off that
6423 /* To simplify things, "continue" is forced to use the same
6424 code paths as single-step - set a breakpoint at the
6425 signal return address and then, once hit, step off that
6427 infrun_debug_printf ("signal arrived while stepping over breakpoint");
6429 insert_hp_step_resume_breakpoint_at_frame (frame
);
6430 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6431 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6432 ecs
->event_thread
->control
.trap_expected
= 0;
6434 /* If we were nexting/stepping some other thread, switch to
6435 it, so that we don't continue it, losing control. */
6436 if (!switch_back_to_stepped_thread (ecs
))
6441 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
6442 && (pc_in_thread_step_range (ecs
->event_thread
->suspend
.stop_pc
,
6444 || ecs
->event_thread
->control
.step_range_end
== 1)
6445 && frame_id_eq (get_stack_frame_id (frame
),
6446 ecs
->event_thread
->control
.step_stack_frame_id
)
6447 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6449 /* The inferior is about to take a signal that will take it
6450 out of the single step range. Set a breakpoint at the
6451 current PC (which is presumably where the signal handler
6452 will eventually return) and then allow the inferior to
6455 Note that this is only needed for a signal delivered
6456 while in the single-step range. Nested signals aren't a
6457 problem as they eventually all return. */
6458 infrun_debug_printf ("signal may take us out of single-step range");
6460 clear_step_over_info ();
6461 insert_hp_step_resume_breakpoint_at_frame (frame
);
6462 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6463 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6464 ecs
->event_thread
->control
.trap_expected
= 0;
6469 /* Note: step_resume_breakpoint may be non-NULL. This occurs
6470 when either there's a nested signal, or when there's a
6471 pending signal enabled just as the signal handler returns
6472 (leaving the inferior at the step-resume-breakpoint without
6473 actually executing it). Either way continue until the
6474 breakpoint is really hit. */
6476 if (!switch_back_to_stepped_thread (ecs
))
6478 infrun_debug_printf ("random signal, keep going");
6485 process_event_stop_test (ecs
);
6488 /* Come here when we've got some debug event / signal we can explain
6489 (IOW, not a random signal), and test whether it should cause a
6490 stop, or whether we should resume the inferior (transparently).
6491 E.g., could be a breakpoint whose condition evaluates false; we
6492 could be still stepping within the line; etc. */
6495 process_event_stop_test (struct execution_control_state
*ecs
)
6497 struct symtab_and_line stop_pc_sal
;
6498 struct frame_info
*frame
;
6499 struct gdbarch
*gdbarch
;
6500 CORE_ADDR jmp_buf_pc
;
6501 struct bpstat_what what
;
6503 /* Handle cases caused by hitting a breakpoint. */
6505 frame
= get_current_frame ();
6506 gdbarch
= get_frame_arch (frame
);
6508 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
6510 if (what
.call_dummy
)
6512 stop_stack_dummy
= what
.call_dummy
;
6515 /* A few breakpoint types have callbacks associated (e.g.,
6516 bp_jit_event). Run them now. */
6517 bpstat_run_callbacks (ecs
->event_thread
->control
.stop_bpstat
);
6519 /* If we hit an internal event that triggers symbol changes, the
6520 current frame will be invalidated within bpstat_what (e.g., if we
6521 hit an internal solib event). Re-fetch it. */
6522 frame
= get_current_frame ();
6523 gdbarch
= get_frame_arch (frame
);
6525 switch (what
.main_action
)
6527 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
6528 /* If we hit the breakpoint at longjmp while stepping, we
6529 install a momentary breakpoint at the target of the
6532 infrun_debug_printf ("BPSTAT_WHAT_SET_LONGJMP_RESUME");
6534 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6536 if (what
.is_longjmp
)
6538 struct value
*arg_value
;
6540 /* If we set the longjmp breakpoint via a SystemTap probe,
6541 then use it to extract the arguments. The destination PC
6542 is the third argument to the probe. */
6543 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
6546 jmp_buf_pc
= value_as_address (arg_value
);
6547 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
6549 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
6550 || !gdbarch_get_longjmp_target (gdbarch
,
6551 frame
, &jmp_buf_pc
))
6553 infrun_debug_printf ("BPSTAT_WHAT_SET_LONGJMP_RESUME "
6554 "(!gdbarch_get_longjmp_target)");
6559 /* Insert a breakpoint at resume address. */
6560 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
6563 check_exception_resume (ecs
, frame
);
6567 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
6569 struct frame_info
*init_frame
;
6571 /* There are several cases to consider.
6573 1. The initiating frame no longer exists. In this case we
6574 must stop, because the exception or longjmp has gone too
6577 2. The initiating frame exists, and is the same as the
6578 current frame. We stop, because the exception or longjmp
6581 3. The initiating frame exists and is different from the
6582 current frame. This means the exception or longjmp has
6583 been caught beneath the initiating frame, so keep going.
6585 4. longjmp breakpoint has been placed just to protect
6586 against stale dummy frames and user is not interested in
6587 stopping around longjmps. */
6589 infrun_debug_printf ("BPSTAT_WHAT_CLEAR_LONGJMP_RESUME");
6591 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
6593 delete_exception_resume_breakpoint (ecs
->event_thread
);
6595 if (what
.is_longjmp
)
6597 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
6599 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
6607 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
6611 struct frame_id current_id
6612 = get_frame_id (get_current_frame ());
6613 if (frame_id_eq (current_id
,
6614 ecs
->event_thread
->initiating_frame
))
6616 /* Case 2. Fall through. */
6626 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6628 delete_step_resume_breakpoint (ecs
->event_thread
);
6630 end_stepping_range (ecs
);
6634 case BPSTAT_WHAT_SINGLE
:
6635 infrun_debug_printf ("BPSTAT_WHAT_SINGLE");
6636 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6637 /* Still need to check other stuff, at least the case where we
6638 are stepping and step out of the right range. */
6641 case BPSTAT_WHAT_STEP_RESUME
:
6642 infrun_debug_printf ("BPSTAT_WHAT_STEP_RESUME");
6644 delete_step_resume_breakpoint (ecs
->event_thread
);
6645 if (ecs
->event_thread
->control
.proceed_to_finish
6646 && execution_direction
== EXEC_REVERSE
)
6648 struct thread_info
*tp
= ecs
->event_thread
;
6650 /* We are finishing a function in reverse, and just hit the
6651 step-resume breakpoint at the start address of the
6652 function, and we're almost there -- just need to back up
6653 by one more single-step, which should take us back to the
6655 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
6659 fill_in_stop_func (gdbarch
, ecs
);
6660 if (ecs
->event_thread
->suspend
.stop_pc
== ecs
->stop_func_start
6661 && execution_direction
== EXEC_REVERSE
)
6663 /* We are stepping over a function call in reverse, and just
6664 hit the step-resume breakpoint at the start address of
6665 the function. Go back to single-stepping, which should
6666 take us back to the function call. */
6667 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6673 case BPSTAT_WHAT_STOP_NOISY
:
6674 infrun_debug_printf ("BPSTAT_WHAT_STOP_NOISY");
6675 stop_print_frame
= true;
6677 /* Assume the thread stopped for a breakpoint. We'll still check
6678 whether a/the breakpoint is there when the thread is next
6680 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6685 case BPSTAT_WHAT_STOP_SILENT
:
6686 infrun_debug_printf ("BPSTAT_WHAT_STOP_SILENT");
6687 stop_print_frame
= false;
6689 /* Assume the thread stopped for a breakpoint. We'll still check
6690 whether a/the breakpoint is there when the thread is next
6692 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6696 case BPSTAT_WHAT_HP_STEP_RESUME
:
6697 infrun_debug_printf ("BPSTAT_WHAT_HP_STEP_RESUME");
6699 delete_step_resume_breakpoint (ecs
->event_thread
);
6700 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
6702 /* Back when the step-resume breakpoint was inserted, we
6703 were trying to single-step off a breakpoint. Go back to
6705 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6706 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6712 case BPSTAT_WHAT_KEEP_CHECKING
:
6716 /* If we stepped a permanent breakpoint and we had a high priority
6717 step-resume breakpoint for the address we stepped, but we didn't
6718 hit it, then we must have stepped into the signal handler. The
6719 step-resume was only necessary to catch the case of _not_
6720 stepping into the handler, so delete it, and fall through to
6721 checking whether the step finished. */
6722 if (ecs
->event_thread
->stepped_breakpoint
)
6724 struct breakpoint
*sr_bp
6725 = ecs
->event_thread
->control
.step_resume_breakpoint
;
6728 && sr_bp
->loc
->permanent
6729 && sr_bp
->type
== bp_hp_step_resume
6730 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
6732 infrun_debug_printf ("stepped permanent breakpoint, stopped in handler");
6733 delete_step_resume_breakpoint (ecs
->event_thread
);
6734 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6738 /* We come here if we hit a breakpoint but should not stop for it.
6739 Possibly we also were stepping and should stop for that. So fall
6740 through and test for stepping. But, if not stepping, do not
6743 /* In all-stop mode, if we're currently stepping but have stopped in
6744 some other thread, we need to switch back to the stepped thread. */
6745 if (switch_back_to_stepped_thread (ecs
))
6748 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
6750 infrun_debug_printf ("step-resume breakpoint is inserted");
6752 /* Having a step-resume breakpoint overrides anything
6753 else having to do with stepping commands until
6754 that breakpoint is reached. */
6759 if (ecs
->event_thread
->control
.step_range_end
== 0)
6761 infrun_debug_printf ("no stepping, continue");
6762 /* Likewise if we aren't even stepping. */
6767 /* Re-fetch current thread's frame in case the code above caused
6768 the frame cache to be re-initialized, making our FRAME variable
6769 a dangling pointer. */
6770 frame
= get_current_frame ();
6771 gdbarch
= get_frame_arch (frame
);
6772 fill_in_stop_func (gdbarch
, ecs
);
6774 /* If stepping through a line, keep going if still within it.
6776 Note that step_range_end is the address of the first instruction
6777 beyond the step range, and NOT the address of the last instruction
6780 Note also that during reverse execution, we may be stepping
6781 through a function epilogue and therefore must detect when
6782 the current-frame changes in the middle of a line. */
6784 if (pc_in_thread_step_range (ecs
->event_thread
->suspend
.stop_pc
,
6786 && (execution_direction
!= EXEC_REVERSE
6787 || frame_id_eq (get_frame_id (frame
),
6788 ecs
->event_thread
->control
.step_frame_id
)))
6791 ("stepping inside range [%s-%s]",
6792 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
6793 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
6795 /* Tentatively re-enable range stepping; `resume' disables it if
6796 necessary (e.g., if we're stepping over a breakpoint or we
6797 have software watchpoints). */
6798 ecs
->event_thread
->control
.may_range_step
= 1;
6800 /* When stepping backward, stop at beginning of line range
6801 (unless it's the function entry point, in which case
6802 keep going back to the call point). */
6803 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6804 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
6805 && stop_pc
!= ecs
->stop_func_start
6806 && execution_direction
== EXEC_REVERSE
)
6807 end_stepping_range (ecs
);
6814 /* We stepped out of the stepping range. */
6816 /* If we are stepping at the source level and entered the runtime
6817 loader dynamic symbol resolution code...
6819 EXEC_FORWARD: we keep on single stepping until we exit the run
6820 time loader code and reach the callee's address.
6822 EXEC_REVERSE: we've already executed the callee (backward), and
6823 the runtime loader code is handled just like any other
6824 undebuggable function call. Now we need only keep stepping
6825 backward through the trampoline code, and that's handled further
6826 down, so there is nothing for us to do here. */
6828 if (execution_direction
!= EXEC_REVERSE
6829 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6830 && in_solib_dynsym_resolve_code (ecs
->event_thread
->suspend
.stop_pc
))
6832 CORE_ADDR pc_after_resolver
=
6833 gdbarch_skip_solib_resolver (gdbarch
,
6834 ecs
->event_thread
->suspend
.stop_pc
);
6836 infrun_debug_printf ("stepped into dynsym resolve code");
6838 if (pc_after_resolver
)
6840 /* Set up a step-resume breakpoint at the address
6841 indicated by SKIP_SOLIB_RESOLVER. */
6842 symtab_and_line sr_sal
;
6843 sr_sal
.pc
= pc_after_resolver
;
6844 sr_sal
.pspace
= get_frame_program_space (frame
);
6846 insert_step_resume_breakpoint_at_sal (gdbarch
,
6847 sr_sal
, null_frame_id
);
6854 /* Step through an indirect branch thunk. */
6855 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6856 && gdbarch_in_indirect_branch_thunk (gdbarch
,
6857 ecs
->event_thread
->suspend
.stop_pc
))
6859 infrun_debug_printf ("stepped into indirect branch thunk");
6864 if (ecs
->event_thread
->control
.step_range_end
!= 1
6865 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6866 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6867 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
6869 infrun_debug_printf ("stepped into signal trampoline");
6870 /* The inferior, while doing a "step" or "next", has ended up in
6871 a signal trampoline (either by a signal being delivered or by
6872 the signal handler returning). Just single-step until the
6873 inferior leaves the trampoline (either by calling the handler
6879 /* If we're in the return path from a shared library trampoline,
6880 we want to proceed through the trampoline when stepping. */
6881 /* macro/2012-04-25: This needs to come before the subroutine
6882 call check below as on some targets return trampolines look
6883 like subroutine calls (MIPS16 return thunks). */
6884 if (gdbarch_in_solib_return_trampoline (gdbarch
,
6885 ecs
->event_thread
->suspend
.stop_pc
,
6886 ecs
->stop_func_name
)
6887 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6889 /* Determine where this trampoline returns. */
6890 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6891 CORE_ADDR real_stop_pc
6892 = gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6894 infrun_debug_printf ("stepped into solib return tramp");
6896 /* Only proceed through if we know where it's going. */
6899 /* And put the step-breakpoint there and go until there. */
6900 symtab_and_line sr_sal
;
6901 sr_sal
.pc
= real_stop_pc
;
6902 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6903 sr_sal
.pspace
= get_frame_program_space (frame
);
6905 /* Do not specify what the fp should be when we stop since
6906 on some machines the prologue is where the new fp value
6908 insert_step_resume_breakpoint_at_sal (gdbarch
,
6909 sr_sal
, null_frame_id
);
6911 /* Restart without fiddling with the step ranges or
6918 /* Check for subroutine calls. The check for the current frame
6919 equalling the step ID is not necessary - the check of the
6920 previous frame's ID is sufficient - but it is a common case and
6921 cheaper than checking the previous frame's ID.
6923 NOTE: frame_id_eq will never report two invalid frame IDs as
6924 being equal, so to get into this block, both the current and
6925 previous frame must have valid frame IDs. */
6926 /* The outer_frame_id check is a heuristic to detect stepping
6927 through startup code. If we step over an instruction which
6928 sets the stack pointer from an invalid value to a valid value,
6929 we may detect that as a subroutine call from the mythical
6930 "outermost" function. This could be fixed by marking
6931 outermost frames as !stack_p,code_p,special_p. Then the
6932 initial outermost frame, before sp was valid, would
6933 have code_addr == &_start. See the comment in frame_id_eq
6935 if (!frame_id_eq (get_stack_frame_id (frame
),
6936 ecs
->event_thread
->control
.step_stack_frame_id
)
6937 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6938 ecs
->event_thread
->control
.step_stack_frame_id
)
6939 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
6941 || (ecs
->event_thread
->control
.step_start_function
6942 != find_pc_function (ecs
->event_thread
->suspend
.stop_pc
)))))
6944 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6945 CORE_ADDR real_stop_pc
;
6947 infrun_debug_printf ("stepped into subroutine");
6949 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
6951 /* I presume that step_over_calls is only 0 when we're
6952 supposed to be stepping at the assembly language level
6953 ("stepi"). Just stop. */
6954 /* And this works the same backward as frontward. MVS */
6955 end_stepping_range (ecs
);
6959 /* Reverse stepping through solib trampolines. */
6961 if (execution_direction
== EXEC_REVERSE
6962 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6963 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6964 || (ecs
->stop_func_start
== 0
6965 && in_solib_dynsym_resolve_code (stop_pc
))))
6967 /* Any solib trampoline code can be handled in reverse
6968 by simply continuing to single-step. We have already
6969 executed the solib function (backwards), and a few
6970 steps will take us back through the trampoline to the
6976 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6978 /* We're doing a "next".
6980 Normal (forward) execution: set a breakpoint at the
6981 callee's return address (the address at which the caller
6984 Reverse (backward) execution. set the step-resume
6985 breakpoint at the start of the function that we just
6986 stepped into (backwards), and continue to there. When we
6987 get there, we'll need to single-step back to the caller. */
6989 if (execution_direction
== EXEC_REVERSE
)
6991 /* If we're already at the start of the function, we've either
6992 just stepped backward into a single instruction function,
6993 or stepped back out of a signal handler to the first instruction
6994 of the function. Just keep going, which will single-step back
6996 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
6998 /* Normal function call return (static or dynamic). */
6999 symtab_and_line sr_sal
;
7000 sr_sal
.pc
= ecs
->stop_func_start
;
7001 sr_sal
.pspace
= get_frame_program_space (frame
);
7002 insert_step_resume_breakpoint_at_sal (gdbarch
,
7003 sr_sal
, null_frame_id
);
7007 insert_step_resume_breakpoint_at_caller (frame
);
7013 /* If we are in a function call trampoline (a stub between the
7014 calling routine and the real function), locate the real
7015 function. That's what tells us (a) whether we want to step
7016 into it at all, and (b) what prologue we want to run to the
7017 end of, if we do step into it. */
7018 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
7019 if (real_stop_pc
== 0)
7020 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
7021 if (real_stop_pc
!= 0)
7022 ecs
->stop_func_start
= real_stop_pc
;
7024 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
7026 symtab_and_line sr_sal
;
7027 sr_sal
.pc
= ecs
->stop_func_start
;
7028 sr_sal
.pspace
= get_frame_program_space (frame
);
7030 insert_step_resume_breakpoint_at_sal (gdbarch
,
7031 sr_sal
, null_frame_id
);
7036 /* If we have line number information for the function we are
7037 thinking of stepping into and the function isn't on the skip
7040 If there are several symtabs at that PC (e.g. with include
7041 files), just want to know whether *any* of them have line
7042 numbers. find_pc_line handles this. */
7044 struct symtab_and_line tmp_sal
;
7046 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7047 if (tmp_sal
.line
!= 0
7048 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
7050 && !inline_frame_is_marked_for_skip (true, ecs
->event_thread
))
7052 if (execution_direction
== EXEC_REVERSE
)
7053 handle_step_into_function_backward (gdbarch
, ecs
);
7055 handle_step_into_function (gdbarch
, ecs
);
7060 /* If we have no line number and the step-stop-if-no-debug is
7061 set, we stop the step so that the user has a chance to switch
7062 in assembly mode. */
7063 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
7064 && step_stop_if_no_debug
)
7066 end_stepping_range (ecs
);
7070 if (execution_direction
== EXEC_REVERSE
)
7072 /* If we're already at the start of the function, we've either just
7073 stepped backward into a single instruction function without line
7074 number info, or stepped back out of a signal handler to the first
7075 instruction of the function without line number info. Just keep
7076 going, which will single-step back to the caller. */
7077 if (ecs
->stop_func_start
!= stop_pc
)
7079 /* Set a breakpoint at callee's start address.
7080 From there we can step once and be back in the caller. */
7081 symtab_and_line sr_sal
;
7082 sr_sal
.pc
= ecs
->stop_func_start
;
7083 sr_sal
.pspace
= get_frame_program_space (frame
);
7084 insert_step_resume_breakpoint_at_sal (gdbarch
,
7085 sr_sal
, null_frame_id
);
7089 /* Set a breakpoint at callee's return address (the address
7090 at which the caller will resume). */
7091 insert_step_resume_breakpoint_at_caller (frame
);
7097 /* Reverse stepping through solib trampolines. */
7099 if (execution_direction
== EXEC_REVERSE
7100 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
7102 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
7104 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
7105 || (ecs
->stop_func_start
== 0
7106 && in_solib_dynsym_resolve_code (stop_pc
)))
7108 /* Any solib trampoline code can be handled in reverse
7109 by simply continuing to single-step. We have already
7110 executed the solib function (backwards), and a few
7111 steps will take us back through the trampoline to the
7116 else if (in_solib_dynsym_resolve_code (stop_pc
))
7118 /* Stepped backward into the solib dynsym resolver.
7119 Set a breakpoint at its start and continue, then
7120 one more step will take us out. */
7121 symtab_and_line sr_sal
;
7122 sr_sal
.pc
= ecs
->stop_func_start
;
7123 sr_sal
.pspace
= get_frame_program_space (frame
);
7124 insert_step_resume_breakpoint_at_sal (gdbarch
,
7125 sr_sal
, null_frame_id
);
7131 /* This always returns the sal for the inner-most frame when we are in a
7132 stack of inlined frames, even if GDB actually believes that it is in a
7133 more outer frame. This is checked for below by calls to
7134 inline_skipped_frames. */
7135 stop_pc_sal
= find_pc_line (ecs
->event_thread
->suspend
.stop_pc
, 0);
7137 /* NOTE: tausq/2004-05-24: This if block used to be done before all
7138 the trampoline processing logic, however, there are some trampolines
7139 that have no names, so we should do trampoline handling first. */
7140 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
7141 && ecs
->stop_func_name
== NULL
7142 && stop_pc_sal
.line
== 0)
7144 infrun_debug_printf ("stepped into undebuggable function");
7146 /* The inferior just stepped into, or returned to, an
7147 undebuggable function (where there is no debugging information
7148 and no line number corresponding to the address where the
7149 inferior stopped). Since we want to skip this kind of code,
7150 we keep going until the inferior returns from this
7151 function - unless the user has asked us not to (via
7152 set step-mode) or we no longer know how to get back
7153 to the call site. */
7154 if (step_stop_if_no_debug
7155 || !frame_id_p (frame_unwind_caller_id (frame
)))
7157 /* If we have no line number and the step-stop-if-no-debug
7158 is set, we stop the step so that the user has a chance to
7159 switch in assembly mode. */
7160 end_stepping_range (ecs
);
7165 /* Set a breakpoint at callee's return address (the address
7166 at which the caller will resume). */
7167 insert_step_resume_breakpoint_at_caller (frame
);
7173 if (ecs
->event_thread
->control
.step_range_end
== 1)
7175 /* It is stepi or nexti. We always want to stop stepping after
7177 infrun_debug_printf ("stepi/nexti");
7178 end_stepping_range (ecs
);
7182 if (stop_pc_sal
.line
== 0)
7184 /* We have no line number information. That means to stop
7185 stepping (does this always happen right after one instruction,
7186 when we do "s" in a function with no line numbers,
7187 or can this happen as a result of a return or longjmp?). */
7188 infrun_debug_printf ("line number info");
7189 end_stepping_range (ecs
);
7193 /* Look for "calls" to inlined functions, part one. If the inline
7194 frame machinery detected some skipped call sites, we have entered
7195 a new inline function. */
7197 if (frame_id_eq (get_frame_id (get_current_frame ()),
7198 ecs
->event_thread
->control
.step_frame_id
)
7199 && inline_skipped_frames (ecs
->event_thread
))
7201 infrun_debug_printf ("stepped into inlined function");
7203 symtab_and_line call_sal
= find_frame_sal (get_current_frame ());
7205 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
7207 /* For "step", we're going to stop. But if the call site
7208 for this inlined function is on the same source line as
7209 we were previously stepping, go down into the function
7210 first. Otherwise stop at the call site. */
7212 if (call_sal
.line
== ecs
->event_thread
->current_line
7213 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
7215 step_into_inline_frame (ecs
->event_thread
);
7216 if (inline_frame_is_marked_for_skip (false, ecs
->event_thread
))
7223 end_stepping_range (ecs
);
7228 /* For "next", we should stop at the call site if it is on a
7229 different source line. Otherwise continue through the
7230 inlined function. */
7231 if (call_sal
.line
== ecs
->event_thread
->current_line
7232 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
7235 end_stepping_range (ecs
);
7240 /* Look for "calls" to inlined functions, part two. If we are still
7241 in the same real function we were stepping through, but we have
7242 to go further up to find the exact frame ID, we are stepping
7243 through a more inlined call beyond its call site. */
7245 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
7246 && !frame_id_eq (get_frame_id (get_current_frame ()),
7247 ecs
->event_thread
->control
.step_frame_id
)
7248 && stepped_in_from (get_current_frame (),
7249 ecs
->event_thread
->control
.step_frame_id
))
7251 infrun_debug_printf ("stepping through inlined function");
7253 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
7254 || inline_frame_is_marked_for_skip (false, ecs
->event_thread
))
7257 end_stepping_range (ecs
);
7261 bool refresh_step_info
= true;
7262 if ((ecs
->event_thread
->suspend
.stop_pc
== stop_pc_sal
.pc
)
7263 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
7264 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
7266 /* We are at a different line. */
7268 if (stop_pc_sal
.is_stmt
)
7270 /* We are at the start of a statement.
7272 So stop. Note that we don't stop if we step into the middle of a
7273 statement. That is said to make things like for (;;) statements
7275 infrun_debug_printf ("stepped to a different line");
7276 end_stepping_range (ecs
);
7279 else if (frame_id_eq (get_frame_id (get_current_frame ()),
7280 ecs
->event_thread
->control
.step_frame_id
))
7282 /* We are not at the start of a statement, and we have not changed
7285 We ignore this line table entry, and continue stepping forward,
7286 looking for a better place to stop. */
7287 refresh_step_info
= false;
7288 infrun_debug_printf ("stepped to a different line, but "
7289 "it's not the start of a statement");
7293 /* We are not the start of a statement, and we have changed frame.
7295 We ignore this line table entry, and continue stepping forward,
7296 looking for a better place to stop. Keep refresh_step_info at
7297 true to note that the frame has changed, but ignore the line
7298 number to make sure we don't ignore a subsequent entry with the
7299 same line number. */
7300 stop_pc_sal
.line
= 0;
7301 infrun_debug_printf ("stepped to a different frame, but "
7302 "it's not the start of a statement");
7306 /* We aren't done stepping.
7308 Optimize by setting the stepping range to the line.
7309 (We might not be in the original line, but if we entered a
7310 new line in mid-statement, we continue stepping. This makes
7311 things like for(;;) statements work better.)
7313 If we entered a SAL that indicates a non-statement line table entry,
7314 then we update the stepping range, but we don't update the step info,
7315 which includes things like the line number we are stepping away from.
7316 This means we will stop when we find a line table entry that is marked
7317 as is-statement, even if it matches the non-statement one we just
7320 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
7321 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
7322 ecs
->event_thread
->control
.may_range_step
= 1;
7323 if (refresh_step_info
)
7324 set_step_info (ecs
->event_thread
, frame
, stop_pc_sal
);
7326 infrun_debug_printf ("keep going");
7330 static bool restart_stepped_thread (process_stratum_target
*resume_target
,
7331 ptid_t resume_ptid
);
7333 /* In all-stop mode, if we're currently stepping but have stopped in
7334 some other thread, we may need to switch back to the stepped
7335 thread. Returns true we set the inferior running, false if we left
7336 it stopped (and the event needs further processing). */
7339 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
7341 if (!target_is_non_stop_p ())
7343 /* If any thread is blocked on some internal breakpoint, and we
7344 simply need to step over that breakpoint to get it going
7345 again, do that first. */
7347 /* However, if we see an event for the stepping thread, then we
7348 know all other threads have been moved past their breakpoints
7349 already. Let the caller check whether the step is finished,
7350 etc., before deciding to move it past a breakpoint. */
7351 if (ecs
->event_thread
->control
.step_range_end
!= 0)
7354 /* Check if the current thread is blocked on an incomplete
7355 step-over, interrupted by a random signal. */
7356 if (ecs
->event_thread
->control
.trap_expected
7357 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
7360 ("need to finish step-over of [%s]",
7361 target_pid_to_str (ecs
->event_thread
->ptid
).c_str ());
7366 /* Check if the current thread is blocked by a single-step
7367 breakpoint of another thread. */
7368 if (ecs
->hit_singlestep_breakpoint
)
7370 infrun_debug_printf ("need to step [%s] over single-step breakpoint",
7371 target_pid_to_str (ecs
->ptid
).c_str ());
7376 /* If this thread needs yet another step-over (e.g., stepping
7377 through a delay slot), do it first before moving on to
7379 if (thread_still_needs_step_over (ecs
->event_thread
))
7382 ("thread [%s] still needs step-over",
7383 target_pid_to_str (ecs
->event_thread
->ptid
).c_str ());
7388 /* If scheduler locking applies even if not stepping, there's no
7389 need to walk over threads. Above we've checked whether the
7390 current thread is stepping. If some other thread not the
7391 event thread is stepping, then it must be that scheduler
7392 locking is not in effect. */
7393 if (schedlock_applies (ecs
->event_thread
))
7396 /* Otherwise, we no longer expect a trap in the current thread.
7397 Clear the trap_expected flag before switching back -- this is
7398 what keep_going does as well, if we call it. */
7399 ecs
->event_thread
->control
.trap_expected
= 0;
7401 /* Likewise, clear the signal if it should not be passed. */
7402 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7403 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7405 if (restart_stepped_thread (ecs
->target
, ecs
->ptid
))
7407 prepare_to_wait (ecs
);
7411 switch_to_thread (ecs
->event_thread
);
7417 /* Look for the thread that was stepping, and resume it.
7418 RESUME_TARGET / RESUME_PTID indicate the set of threads the caller
7419 is resuming. Return true if a thread was started, false
7423 restart_stepped_thread (process_stratum_target
*resume_target
,
7426 /* Do all pending step-overs before actually proceeding with
7428 if (start_step_over ())
7431 for (thread_info
*tp
: all_threads_safe ())
7433 if (tp
->state
== THREAD_EXITED
)
7436 if (tp
->suspend
.waitstatus_pending_p
)
7439 /* Ignore threads of processes the caller is not
7442 && (tp
->inf
->process_target () != resume_target
7443 || tp
->inf
->pid
!= resume_ptid
.pid ()))
7446 if (tp
->control
.trap_expected
)
7448 infrun_debug_printf ("switching back to stepped thread (step-over)");
7450 if (keep_going_stepped_thread (tp
))
7455 for (thread_info
*tp
: all_threads_safe ())
7457 if (tp
->state
== THREAD_EXITED
)
7460 if (tp
->suspend
.waitstatus_pending_p
)
7463 /* Ignore threads of processes the caller is not
7466 && (tp
->inf
->process_target () != resume_target
7467 || tp
->inf
->pid
!= resume_ptid
.pid ()))
7470 /* Did we find the stepping thread? */
7471 if (tp
->control
.step_range_end
)
7473 infrun_debug_printf ("switching back to stepped thread (stepping)");
7475 if (keep_going_stepped_thread (tp
))
7486 restart_after_all_stop_detach (process_stratum_target
*proc_target
)
7488 /* Note we don't check target_is_non_stop_p() here, because the
7489 current inferior may no longer have a process_stratum target
7490 pushed, as we just detached. */
7492 /* See if we have a THREAD_RUNNING thread that need to be
7493 re-resumed. If we have any thread that is already executing,
7494 then we don't need to resume the target -- it is already been
7495 resumed. With the remote target (in all-stop), it's even
7496 impossible to issue another resumption if the target is already
7497 resumed, until the target reports a stop. */
7498 for (thread_info
*thr
: all_threads (proc_target
))
7500 if (thr
->state
!= THREAD_RUNNING
)
7503 /* If we have any thread that is already executing, then we
7504 don't need to resume the target -- it is already been
7509 /* If we have a pending event to process, skip resuming the
7510 target and go straight to processing it. */
7511 if (thr
->resumed
&& thr
->suspend
.waitstatus_pending_p
)
7515 /* Alright, we need to re-resume the target. If a thread was
7516 stepping, we need to restart it stepping. */
7517 if (restart_stepped_thread (proc_target
, minus_one_ptid
))
7520 /* Otherwise, find the first THREAD_RUNNING thread and resume
7522 for (thread_info
*thr
: all_threads (proc_target
))
7524 if (thr
->state
!= THREAD_RUNNING
)
7527 execution_control_state ecs
;
7528 reset_ecs (&ecs
, thr
);
7529 switch_to_thread (thr
);
7535 /* Set a previously stepped thread back to stepping. Returns true on
7536 success, false if the resume is not possible (e.g., the thread
7540 keep_going_stepped_thread (struct thread_info
*tp
)
7542 struct frame_info
*frame
;
7543 struct execution_control_state ecss
;
7544 struct execution_control_state
*ecs
= &ecss
;
7546 /* If the stepping thread exited, then don't try to switch back and
7547 resume it, which could fail in several different ways depending
7548 on the target. Instead, just keep going.
7550 We can find a stepping dead thread in the thread list in two
7553 - The target supports thread exit events, and when the target
7554 tries to delete the thread from the thread list, inferior_ptid
7555 pointed at the exiting thread. In such case, calling
7556 delete_thread does not really remove the thread from the list;
7557 instead, the thread is left listed, with 'exited' state.
7559 - The target's debug interface does not support thread exit
7560 events, and so we have no idea whatsoever if the previously
7561 stepping thread is still alive. For that reason, we need to
7562 synchronously query the target now. */
7564 if (tp
->state
== THREAD_EXITED
|| !target_thread_alive (tp
->ptid
))
7566 infrun_debug_printf ("not resuming previously stepped thread, it has "
7573 infrun_debug_printf ("resuming previously stepped thread");
7575 reset_ecs (ecs
, tp
);
7576 switch_to_thread (tp
);
7578 tp
->suspend
.stop_pc
= regcache_read_pc (get_thread_regcache (tp
));
7579 frame
= get_current_frame ();
7581 /* If the PC of the thread we were trying to single-step has
7582 changed, then that thread has trapped or been signaled, but the
7583 event has not been reported to GDB yet. Re-poll the target
7584 looking for this particular thread's event (i.e. temporarily
7585 enable schedlock) by:
7587 - setting a break at the current PC
7588 - resuming that particular thread, only (by setting trap
7591 This prevents us continuously moving the single-step breakpoint
7592 forward, one instruction at a time, overstepping. */
7594 if (tp
->suspend
.stop_pc
!= tp
->prev_pc
)
7598 infrun_debug_printf ("expected thread advanced also (%s -> %s)",
7599 paddress (target_gdbarch (), tp
->prev_pc
),
7600 paddress (target_gdbarch (), tp
->suspend
.stop_pc
));
7602 /* Clear the info of the previous step-over, as it's no longer
7603 valid (if the thread was trying to step over a breakpoint, it
7604 has already succeeded). It's what keep_going would do too,
7605 if we called it. Do this before trying to insert the sss
7606 breakpoint, otherwise if we were previously trying to step
7607 over this exact address in another thread, the breakpoint is
7609 clear_step_over_info ();
7610 tp
->control
.trap_expected
= 0;
7612 insert_single_step_breakpoint (get_frame_arch (frame
),
7613 get_frame_address_space (frame
),
7614 tp
->suspend
.stop_pc
);
7617 resume_ptid
= internal_resume_ptid (tp
->control
.stepping_command
);
7618 do_target_resume (resume_ptid
, false, GDB_SIGNAL_0
);
7622 infrun_debug_printf ("expected thread still hasn't advanced");
7624 keep_going_pass_signal (ecs
);
7630 /* Is thread TP in the middle of (software or hardware)
7631 single-stepping? (Note the result of this function must never be
7632 passed directly as target_resume's STEP parameter.) */
7635 currently_stepping (struct thread_info
*tp
)
7637 return ((tp
->control
.step_range_end
7638 && tp
->control
.step_resume_breakpoint
== NULL
)
7639 || tp
->control
.trap_expected
7640 || tp
->stepped_breakpoint
7641 || bpstat_should_step ());
7644 /* Inferior has stepped into a subroutine call with source code that
7645 we should not step over. Do step to the first line of code in
7649 handle_step_into_function (struct gdbarch
*gdbarch
,
7650 struct execution_control_state
*ecs
)
7652 fill_in_stop_func (gdbarch
, ecs
);
7654 compunit_symtab
*cust
7655 = find_pc_compunit_symtab (ecs
->event_thread
->suspend
.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 symtab_and_line stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7661 /* Use the step_resume_break to step until the end of the prologue,
7662 even if that involves jumps (as it seems to on the vax under
7664 /* If the prologue ends in the middle of a source line, continue to
7665 the end of that source line (if it is still within the function).
7666 Otherwise, just go to end of prologue. */
7667 if (stop_func_sal
.end
7668 && stop_func_sal
.pc
!= ecs
->stop_func_start
7669 && stop_func_sal
.end
< ecs
->stop_func_end
)
7670 ecs
->stop_func_start
= stop_func_sal
.end
;
7672 /* Architectures which require breakpoint adjustment might not be able
7673 to place a breakpoint at the computed address. If so, the test
7674 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7675 ecs->stop_func_start to an address at which a breakpoint may be
7676 legitimately placed.
7678 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7679 made, GDB will enter an infinite loop when stepping through
7680 optimized code consisting of VLIW instructions which contain
7681 subinstructions corresponding to different source lines. On
7682 FR-V, it's not permitted to place a breakpoint on any but the
7683 first subinstruction of a VLIW instruction. When a breakpoint is
7684 set, GDB will adjust the breakpoint address to the beginning of
7685 the VLIW instruction. Thus, we need to make the corresponding
7686 adjustment here when computing the stop address. */
7688 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
7690 ecs
->stop_func_start
7691 = gdbarch_adjust_breakpoint_address (gdbarch
,
7692 ecs
->stop_func_start
);
7695 if (ecs
->stop_func_start
== ecs
->event_thread
->suspend
.stop_pc
)
7697 /* We are already there: stop now. */
7698 end_stepping_range (ecs
);
7703 /* Put the step-breakpoint there and go until there. */
7704 symtab_and_line sr_sal
;
7705 sr_sal
.pc
= ecs
->stop_func_start
;
7706 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
7707 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
7709 /* Do not specify what the fp should be when we stop since on
7710 some machines the prologue is where the new fp value is
7712 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
7714 /* And make sure stepping stops right away then. */
7715 ecs
->event_thread
->control
.step_range_end
7716 = ecs
->event_thread
->control
.step_range_start
;
7721 /* Inferior has stepped backward into a subroutine call with source
7722 code that we should not step over. Do step to the beginning of the
7723 last line of code in it. */
7726 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
7727 struct execution_control_state
*ecs
)
7729 struct compunit_symtab
*cust
;
7730 struct symtab_and_line stop_func_sal
;
7732 fill_in_stop_func (gdbarch
, ecs
);
7734 cust
= find_pc_compunit_symtab (ecs
->event_thread
->suspend
.stop_pc
);
7735 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7736 ecs
->stop_func_start
7737 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7739 stop_func_sal
= find_pc_line (ecs
->event_thread
->suspend
.stop_pc
, 0);
7741 /* OK, we're just going to keep stepping here. */
7742 if (stop_func_sal
.pc
== ecs
->event_thread
->suspend
.stop_pc
)
7744 /* We're there already. Just stop stepping now. */
7745 end_stepping_range (ecs
);
7749 /* Else just reset the step range and keep going.
7750 No step-resume breakpoint, they don't work for
7751 epilogues, which can have multiple entry paths. */
7752 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
7753 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
7759 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7760 This is used to both functions and to skip over code. */
7763 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
7764 struct symtab_and_line sr_sal
,
7765 struct frame_id sr_id
,
7766 enum bptype sr_type
)
7768 /* There should never be more than one step-resume or longjmp-resume
7769 breakpoint per thread, so we should never be setting a new
7770 step_resume_breakpoint when one is already active. */
7771 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
7772 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
7774 infrun_debug_printf ("inserting step-resume breakpoint at %s",
7775 paddress (gdbarch
, sr_sal
.pc
));
7777 inferior_thread ()->control
.step_resume_breakpoint
7778 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
).release ();
7782 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
7783 struct symtab_and_line sr_sal
,
7784 struct frame_id sr_id
)
7786 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
7791 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7792 This is used to skip a potential signal handler.
7794 This is called with the interrupted function's frame. The signal
7795 handler, when it returns, will resume the interrupted function at
7799 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
7801 gdb_assert (return_frame
!= NULL
);
7803 struct gdbarch
*gdbarch
= get_frame_arch (return_frame
);
7805 symtab_and_line sr_sal
;
7806 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
7807 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7808 sr_sal
.pspace
= get_frame_program_space (return_frame
);
7810 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
7811 get_stack_frame_id (return_frame
),
7815 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7816 is used to skip a function after stepping into it (for "next" or if
7817 the called function has no debugging information).
7819 The current function has almost always been reached by single
7820 stepping a call or return instruction. NEXT_FRAME belongs to the
7821 current function, and the breakpoint will be set at the caller's
7824 This is a separate function rather than reusing
7825 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7826 get_prev_frame, which may stop prematurely (see the implementation
7827 of frame_unwind_caller_id for an example). */
7830 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
7832 /* We shouldn't have gotten here if we don't know where the call site
7834 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
7836 struct gdbarch
*gdbarch
= frame_unwind_caller_arch (next_frame
);
7838 symtab_and_line sr_sal
;
7839 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
7840 frame_unwind_caller_pc (next_frame
));
7841 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7842 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
7844 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
7845 frame_unwind_caller_id (next_frame
));
7848 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7849 new breakpoint at the target of a jmp_buf. The handling of
7850 longjmp-resume uses the same mechanisms used for handling
7851 "step-resume" breakpoints. */
7854 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
7856 /* There should never be more than one longjmp-resume breakpoint per
7857 thread, so we should never be setting a new
7858 longjmp_resume_breakpoint when one is already active. */
7859 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
7861 infrun_debug_printf ("inserting longjmp-resume breakpoint at %s",
7862 paddress (gdbarch
, pc
));
7864 inferior_thread ()->control
.exception_resume_breakpoint
=
7865 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
).release ();
7868 /* Insert an exception resume breakpoint. TP is the thread throwing
7869 the exception. The block B is the block of the unwinder debug hook
7870 function. FRAME is the frame corresponding to the call to this
7871 function. SYM is the symbol of the function argument holding the
7872 target PC of the exception. */
7875 insert_exception_resume_breakpoint (struct thread_info
*tp
,
7876 const struct block
*b
,
7877 struct frame_info
*frame
,
7882 struct block_symbol vsym
;
7883 struct value
*value
;
7885 struct breakpoint
*bp
;
7887 vsym
= lookup_symbol_search_name (sym
->search_name (),
7889 value
= read_var_value (vsym
.symbol
, vsym
.block
, frame
);
7890 /* If the value was optimized out, revert to the old behavior. */
7891 if (! value_optimized_out (value
))
7893 handler
= value_as_address (value
);
7895 infrun_debug_printf ("exception resume at %lx",
7896 (unsigned long) handler
);
7898 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7900 bp_exception_resume
).release ();
7902 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7905 bp
->thread
= tp
->global_num
;
7906 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7909 catch (const gdb_exception_error
&e
)
7911 /* We want to ignore errors here. */
7915 /* A helper for check_exception_resume that sets an
7916 exception-breakpoint based on a SystemTap probe. */
7919 insert_exception_resume_from_probe (struct thread_info
*tp
,
7920 const struct bound_probe
*probe
,
7921 struct frame_info
*frame
)
7923 struct value
*arg_value
;
7925 struct breakpoint
*bp
;
7927 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
7931 handler
= value_as_address (arg_value
);
7933 infrun_debug_printf ("exception resume at %s",
7934 paddress (probe
->objfile
->arch (), handler
));
7936 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7937 handler
, bp_exception_resume
).release ();
7938 bp
->thread
= tp
->global_num
;
7939 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7942 /* This is called when an exception has been intercepted. Check to
7943 see whether the exception's destination is of interest, and if so,
7944 set an exception resume breakpoint there. */
7947 check_exception_resume (struct execution_control_state
*ecs
,
7948 struct frame_info
*frame
)
7950 struct bound_probe probe
;
7951 struct symbol
*func
;
7953 /* First see if this exception unwinding breakpoint was set via a
7954 SystemTap probe point. If so, the probe has two arguments: the
7955 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7956 set a breakpoint there. */
7957 probe
= find_probe_by_pc (get_frame_pc (frame
));
7960 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
7964 func
= get_frame_function (frame
);
7970 const struct block
*b
;
7971 struct block_iterator iter
;
7975 /* The exception breakpoint is a thread-specific breakpoint on
7976 the unwinder's debug hook, declared as:
7978 void _Unwind_DebugHook (void *cfa, void *handler);
7980 The CFA argument indicates the frame to which control is
7981 about to be transferred. HANDLER is the destination PC.
7983 We ignore the CFA and set a temporary breakpoint at HANDLER.
7984 This is not extremely efficient but it avoids issues in gdb
7985 with computing the DWARF CFA, and it also works even in weird
7986 cases such as throwing an exception from inside a signal
7989 b
= SYMBOL_BLOCK_VALUE (func
);
7990 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
7992 if (!SYMBOL_IS_ARGUMENT (sym
))
7999 insert_exception_resume_breakpoint (ecs
->event_thread
,
8005 catch (const gdb_exception_error
&e
)
8011 stop_waiting (struct execution_control_state
*ecs
)
8013 infrun_debug_printf ("stop_waiting");
8015 /* Let callers know we don't want to wait for the inferior anymore. */
8016 ecs
->wait_some_more
= 0;
8018 /* If all-stop, but there exists a non-stop target, stop all
8019 threads now that we're presenting the stop to the user. */
8020 if (!non_stop
&& exists_non_stop_target ())
8021 stop_all_threads ();
8024 /* Like keep_going, but passes the signal to the inferior, even if the
8025 signal is set to nopass. */
8028 keep_going_pass_signal (struct execution_control_state
*ecs
)
8030 gdb_assert (ecs
->event_thread
->ptid
== inferior_ptid
);
8031 gdb_assert (!ecs
->event_thread
->resumed
);
8033 /* Save the pc before execution, to compare with pc after stop. */
8034 ecs
->event_thread
->prev_pc
8035 = regcache_read_pc_protected (get_thread_regcache (ecs
->event_thread
));
8037 if (ecs
->event_thread
->control
.trap_expected
)
8039 struct thread_info
*tp
= ecs
->event_thread
;
8041 infrun_debug_printf ("%s has trap_expected set, "
8042 "resuming to collect trap",
8043 target_pid_to_str (tp
->ptid
).c_str ());
8045 /* We haven't yet gotten our trap, and either: intercepted a
8046 non-signal event (e.g., a fork); or took a signal which we
8047 are supposed to pass through to the inferior. Simply
8049 resume (ecs
->event_thread
->suspend
.stop_signal
);
8051 else if (step_over_info_valid_p ())
8053 /* Another thread is stepping over a breakpoint in-line. If
8054 this thread needs a step-over too, queue the request. In
8055 either case, this resume must be deferred for later. */
8056 struct thread_info
*tp
= ecs
->event_thread
;
8058 if (ecs
->hit_singlestep_breakpoint
8059 || thread_still_needs_step_over (tp
))
8061 infrun_debug_printf ("step-over already in progress: "
8062 "step-over for %s deferred",
8063 target_pid_to_str (tp
->ptid
).c_str ());
8064 global_thread_step_over_chain_enqueue (tp
);
8068 infrun_debug_printf ("step-over in progress: resume of %s deferred",
8069 target_pid_to_str (tp
->ptid
).c_str ());
8074 struct regcache
*regcache
= get_current_regcache ();
8077 step_over_what step_what
;
8079 /* Either the trap was not expected, but we are continuing
8080 anyway (if we got a signal, the user asked it be passed to
8083 We got our expected trap, but decided we should resume from
8086 We're going to run this baby now!
8088 Note that insert_breakpoints won't try to re-insert
8089 already inserted breakpoints. Therefore, we don't
8090 care if breakpoints were already inserted, or not. */
8092 /* If we need to step over a breakpoint, and we're not using
8093 displaced stepping to do so, insert all breakpoints
8094 (watchpoints, etc.) but the one we're stepping over, step one
8095 instruction, and then re-insert the breakpoint when that step
8098 step_what
= thread_still_needs_step_over (ecs
->event_thread
);
8100 remove_bp
= (ecs
->hit_singlestep_breakpoint
8101 || (step_what
& STEP_OVER_BREAKPOINT
));
8102 remove_wps
= (step_what
& STEP_OVER_WATCHPOINT
);
8104 /* We can't use displaced stepping if we need to step past a
8105 watchpoint. The instruction copied to the scratch pad would
8106 still trigger the watchpoint. */
8108 && (remove_wps
|| !use_displaced_stepping (ecs
->event_thread
)))
8110 set_step_over_info (regcache
->aspace (),
8111 regcache_read_pc (regcache
), remove_wps
,
8112 ecs
->event_thread
->global_num
);
8114 else if (remove_wps
)
8115 set_step_over_info (NULL
, 0, remove_wps
, -1);
8117 /* If we now need to do an in-line step-over, we need to stop
8118 all other threads. Note this must be done before
8119 insert_breakpoints below, because that removes the breakpoint
8120 we're about to step over, otherwise other threads could miss
8122 if (step_over_info_valid_p () && target_is_non_stop_p ())
8123 stop_all_threads ();
8125 /* Stop stepping if inserting breakpoints fails. */
8128 insert_breakpoints ();
8130 catch (const gdb_exception_error
&e
)
8132 exception_print (gdb_stderr
, e
);
8134 clear_step_over_info ();
8138 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
8140 resume (ecs
->event_thread
->suspend
.stop_signal
);
8143 prepare_to_wait (ecs
);
8146 /* Called when we should continue running the inferior, because the
8147 current event doesn't cause a user visible stop. This does the
8148 resuming part; waiting for the next event is done elsewhere. */
8151 keep_going (struct execution_control_state
*ecs
)
8153 if (ecs
->event_thread
->control
.trap_expected
8154 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
8155 ecs
->event_thread
->control
.trap_expected
= 0;
8157 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
8158 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
8159 keep_going_pass_signal (ecs
);
8162 /* This function normally comes after a resume, before
8163 handle_inferior_event exits. It takes care of any last bits of
8164 housekeeping, and sets the all-important wait_some_more flag. */
8167 prepare_to_wait (struct execution_control_state
*ecs
)
8169 infrun_debug_printf ("prepare_to_wait");
8171 ecs
->wait_some_more
= 1;
8173 /* If the target can't async, emulate it by marking the infrun event
8174 handler such that as soon as we get back to the event-loop, we
8175 immediately end up in fetch_inferior_event again calling
8177 if (!target_can_async_p ())
8178 mark_infrun_async_event_handler ();
8181 /* We are done with the step range of a step/next/si/ni command.
8182 Called once for each n of a "step n" operation. */
8185 end_stepping_range (struct execution_control_state
*ecs
)
8187 ecs
->event_thread
->control
.stop_step
= 1;
8191 /* Several print_*_reason functions to print why the inferior has stopped.
8192 We always print something when the inferior exits, or receives a signal.
8193 The rest of the cases are dealt with later on in normal_stop and
8194 print_it_typical. Ideally there should be a call to one of these
8195 print_*_reason functions functions from handle_inferior_event each time
8196 stop_waiting is called.
8198 Note that we don't call these directly, instead we delegate that to
8199 the interpreters, through observers. Interpreters then call these
8200 with whatever uiout is right. */
8203 print_end_stepping_range_reason (struct ui_out
*uiout
)
8205 /* For CLI-like interpreters, print nothing. */
8207 if (uiout
->is_mi_like_p ())
8209 uiout
->field_string ("reason",
8210 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
8215 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
8217 annotate_signalled ();
8218 if (uiout
->is_mi_like_p ())
8220 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
8221 uiout
->text ("\nProgram terminated with signal ");
8222 annotate_signal_name ();
8223 uiout
->field_string ("signal-name",
8224 gdb_signal_to_name (siggnal
));
8225 annotate_signal_name_end ();
8227 annotate_signal_string ();
8228 uiout
->field_string ("signal-meaning",
8229 gdb_signal_to_string (siggnal
));
8230 annotate_signal_string_end ();
8231 uiout
->text (".\n");
8232 uiout
->text ("The program no longer exists.\n");
8236 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
8238 struct inferior
*inf
= current_inferior ();
8239 std::string pidstr
= target_pid_to_str (ptid_t (inf
->pid
));
8241 annotate_exited (exitstatus
);
8244 if (uiout
->is_mi_like_p ())
8245 uiout
->field_string ("reason", async_reason_lookup (EXEC_ASYNC_EXITED
));
8246 std::string exit_code_str
8247 = string_printf ("0%o", (unsigned int) exitstatus
);
8248 uiout
->message ("[Inferior %s (%s) exited with code %pF]\n",
8249 plongest (inf
->num
), pidstr
.c_str (),
8250 string_field ("exit-code", exit_code_str
.c_str ()));
8254 if (uiout
->is_mi_like_p ())
8256 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
8257 uiout
->message ("[Inferior %s (%s) exited normally]\n",
8258 plongest (inf
->num
), pidstr
.c_str ());
8263 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
8265 struct thread_info
*thr
= inferior_thread ();
8269 if (uiout
->is_mi_like_p ())
8271 else if (show_thread_that_caused_stop ())
8275 uiout
->text ("\nThread ");
8276 uiout
->field_string ("thread-id", print_thread_id (thr
));
8278 name
= thr
->name
!= NULL
? thr
->name
: target_thread_name (thr
);
8281 uiout
->text (" \"");
8282 uiout
->field_string ("name", name
);
8287 uiout
->text ("\nProgram");
8289 if (siggnal
== GDB_SIGNAL_0
&& !uiout
->is_mi_like_p ())
8290 uiout
->text (" stopped");
8293 uiout
->text (" received signal ");
8294 annotate_signal_name ();
8295 if (uiout
->is_mi_like_p ())
8297 ("reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
8298 uiout
->field_string ("signal-name", gdb_signal_to_name (siggnal
));
8299 annotate_signal_name_end ();
8301 annotate_signal_string ();
8302 uiout
->field_string ("signal-meaning", gdb_signal_to_string (siggnal
));
8304 struct regcache
*regcache
= get_current_regcache ();
8305 struct gdbarch
*gdbarch
= regcache
->arch ();
8306 if (gdbarch_report_signal_info_p (gdbarch
))
8307 gdbarch_report_signal_info (gdbarch
, uiout
, siggnal
);
8309 annotate_signal_string_end ();
8311 uiout
->text (".\n");
8315 print_no_history_reason (struct ui_out
*uiout
)
8317 uiout
->text ("\nNo more reverse-execution history.\n");
8320 /* Print current location without a level number, if we have changed
8321 functions or hit a breakpoint. Print source line if we have one.
8322 bpstat_print contains the logic deciding in detail what to print,
8323 based on the event(s) that just occurred. */
8326 print_stop_location (struct target_waitstatus
*ws
)
8329 enum print_what source_flag
;
8330 int do_frame_printing
= 1;
8331 struct thread_info
*tp
= inferior_thread ();
8333 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
8337 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
8338 should) carry around the function and does (or should) use
8339 that when doing a frame comparison. */
8340 if (tp
->control
.stop_step
8341 && frame_id_eq (tp
->control
.step_frame_id
,
8342 get_frame_id (get_current_frame ()))
8343 && (tp
->control
.step_start_function
8344 == find_pc_function (tp
->suspend
.stop_pc
)))
8346 /* Finished step, just print source line. */
8347 source_flag
= SRC_LINE
;
8351 /* Print location and source line. */
8352 source_flag
= SRC_AND_LOC
;
8355 case PRINT_SRC_AND_LOC
:
8356 /* Print location and source line. */
8357 source_flag
= SRC_AND_LOC
;
8359 case PRINT_SRC_ONLY
:
8360 source_flag
= SRC_LINE
;
8363 /* Something bogus. */
8364 source_flag
= SRC_LINE
;
8365 do_frame_printing
= 0;
8368 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
8371 /* The behavior of this routine with respect to the source
8373 SRC_LINE: Print only source line
8374 LOCATION: Print only location
8375 SRC_AND_LOC: Print location and source line. */
8376 if (do_frame_printing
)
8377 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
8383 print_stop_event (struct ui_out
*uiout
, bool displays
)
8385 struct target_waitstatus last
;
8386 struct thread_info
*tp
;
8388 get_last_target_status (nullptr, nullptr, &last
);
8391 scoped_restore save_uiout
= make_scoped_restore (¤t_uiout
, uiout
);
8393 print_stop_location (&last
);
8395 /* Display the auto-display expressions. */
8400 tp
= inferior_thread ();
8401 if (tp
->thread_fsm
!= NULL
8402 && tp
->thread_fsm
->finished_p ())
8404 struct return_value_info
*rv
;
8406 rv
= tp
->thread_fsm
->return_value ();
8408 print_return_value (uiout
, rv
);
8415 maybe_remove_breakpoints (void)
8417 if (!breakpoints_should_be_inserted_now () && target_has_execution ())
8419 if (remove_breakpoints ())
8421 target_terminal::ours_for_output ();
8422 printf_filtered (_("Cannot remove breakpoints because "
8423 "program is no longer writable.\nFurther "
8424 "execution is probably impossible.\n"));
8429 /* The execution context that just caused a normal stop. */
8435 DISABLE_COPY_AND_ASSIGN (stop_context
);
8437 bool changed () const;
8442 /* The event PTID. */
8446 /* If stopp for a thread event, this is the thread that caused the
8448 thread_info_ref thread
;
8450 /* The inferior that caused the stop. */
8454 /* Initializes a new stop context. If stopped for a thread event, this
8455 takes a strong reference to the thread. */
8457 stop_context::stop_context ()
8459 stop_id
= get_stop_id ();
8460 ptid
= inferior_ptid
;
8461 inf_num
= current_inferior ()->num
;
8463 if (inferior_ptid
!= null_ptid
)
8465 /* Take a strong reference so that the thread can't be deleted
8467 thread
= thread_info_ref::new_reference (inferior_thread ());
8471 /* Return true if the current context no longer matches the saved stop
8475 stop_context::changed () const
8477 if (ptid
!= inferior_ptid
)
8479 if (inf_num
!= current_inferior ()->num
)
8481 if (thread
!= NULL
&& thread
->state
!= THREAD_STOPPED
)
8483 if (get_stop_id () != stop_id
)
8493 struct target_waitstatus last
;
8495 get_last_target_status (nullptr, nullptr, &last
);
8499 /* If an exception is thrown from this point on, make sure to
8500 propagate GDB's knowledge of the executing state to the
8501 frontend/user running state. A QUIT is an easy exception to see
8502 here, so do this before any filtered output. */
8504 ptid_t finish_ptid
= null_ptid
;
8507 finish_ptid
= minus_one_ptid
;
8508 else if (last
.kind
== TARGET_WAITKIND_SIGNALLED
8509 || last
.kind
== TARGET_WAITKIND_EXITED
)
8511 /* On some targets, we may still have live threads in the
8512 inferior when we get a process exit event. E.g., for
8513 "checkpoint", when the current checkpoint/fork exits,
8514 linux-fork.c automatically switches to another fork from
8515 within target_mourn_inferior. */
8516 if (inferior_ptid
!= null_ptid
)
8517 finish_ptid
= ptid_t (inferior_ptid
.pid ());
8519 else if (last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8520 finish_ptid
= inferior_ptid
;
8522 gdb::optional
<scoped_finish_thread_state
> maybe_finish_thread_state
;
8523 if (finish_ptid
!= null_ptid
)
8525 maybe_finish_thread_state
.emplace
8526 (user_visible_resume_target (finish_ptid
), finish_ptid
);
8529 /* As we're presenting a stop, and potentially removing breakpoints,
8530 update the thread list so we can tell whether there are threads
8531 running on the target. With target remote, for example, we can
8532 only learn about new threads when we explicitly update the thread
8533 list. Do this before notifying the interpreters about signal
8534 stops, end of stepping ranges, etc., so that the "new thread"
8535 output is emitted before e.g., "Program received signal FOO",
8536 instead of after. */
8537 update_thread_list ();
8539 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
8540 gdb::observers::signal_received
.notify (inferior_thread ()->suspend
.stop_signal
);
8542 /* As with the notification of thread events, we want to delay
8543 notifying the user that we've switched thread context until
8544 the inferior actually stops.
8546 There's no point in saying anything if the inferior has exited.
8547 Note that SIGNALLED here means "exited with a signal", not
8548 "received a signal".
8550 Also skip saying anything in non-stop mode. In that mode, as we
8551 don't want GDB to switch threads behind the user's back, to avoid
8552 races where the user is typing a command to apply to thread x,
8553 but GDB switches to thread y before the user finishes entering
8554 the command, fetch_inferior_event installs a cleanup to restore
8555 the current thread back to the thread the user had selected right
8556 after this event is handled, so we're not really switching, only
8557 informing of a stop. */
8559 && previous_inferior_ptid
!= inferior_ptid
8560 && target_has_execution ()
8561 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
8562 && last
.kind
!= TARGET_WAITKIND_EXITED
8563 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8565 SWITCH_THRU_ALL_UIS ()
8567 target_terminal::ours_for_output ();
8568 printf_filtered (_("[Switching to %s]\n"),
8569 target_pid_to_str (inferior_ptid
).c_str ());
8570 annotate_thread_changed ();
8572 previous_inferior_ptid
= inferior_ptid
;
8575 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
8577 SWITCH_THRU_ALL_UIS ()
8578 if (current_ui
->prompt_state
== PROMPT_BLOCKED
)
8580 target_terminal::ours_for_output ();
8581 printf_filtered (_("No unwaited-for children left.\n"));
8585 /* Note: this depends on the update_thread_list call above. */
8586 maybe_remove_breakpoints ();
8588 /* If an auto-display called a function and that got a signal,
8589 delete that auto-display to avoid an infinite recursion. */
8591 if (stopped_by_random_signal
)
8592 disable_current_display ();
8594 SWITCH_THRU_ALL_UIS ()
8596 async_enable_stdin ();
8599 /* Let the user/frontend see the threads as stopped. */
8600 maybe_finish_thread_state
.reset ();
8602 /* Select innermost stack frame - i.e., current frame is frame 0,
8603 and current location is based on that. Handle the case where the
8604 dummy call is returning after being stopped. E.g. the dummy call
8605 previously hit a breakpoint. (If the dummy call returns
8606 normally, we won't reach here.) Do this before the stop hook is
8607 run, so that it doesn't get to see the temporary dummy frame,
8608 which is not where we'll present the stop. */
8609 if (has_stack_frames ())
8611 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
8613 /* Pop the empty frame that contains the stack dummy. This
8614 also restores inferior state prior to the call (struct
8615 infcall_suspend_state). */
8616 struct frame_info
*frame
= get_current_frame ();
8618 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
8620 /* frame_pop calls reinit_frame_cache as the last thing it
8621 does which means there's now no selected frame. */
8624 select_frame (get_current_frame ());
8626 /* Set the current source location. */
8627 set_current_sal_from_frame (get_current_frame ());
8630 /* Look up the hook_stop and run it (CLI internally handles problem
8631 of stop_command's pre-hook not existing). */
8632 if (stop_command
!= NULL
)
8634 stop_context saved_context
;
8638 execute_cmd_pre_hook (stop_command
);
8640 catch (const gdb_exception
&ex
)
8642 exception_fprintf (gdb_stderr
, ex
,
8643 "Error while running hook_stop:\n");
8646 /* If the stop hook resumes the target, then there's no point in
8647 trying to notify about the previous stop; its context is
8648 gone. Likewise if the command switches thread or inferior --
8649 the observers would print a stop for the wrong
8651 if (saved_context
.changed ())
8655 /* Notify observers about the stop. This is where the interpreters
8656 print the stop event. */
8657 if (inferior_ptid
!= null_ptid
)
8658 gdb::observers::normal_stop
.notify (inferior_thread ()->control
.stop_bpstat
,
8661 gdb::observers::normal_stop
.notify (NULL
, stop_print_frame
);
8663 annotate_stopped ();
8665 if (target_has_execution ())
8667 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
8668 && last
.kind
!= TARGET_WAITKIND_EXITED
8669 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8670 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8671 Delete any breakpoint that is to be deleted at the next stop. */
8672 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
8675 /* Try to get rid of automatically added inferiors that are no
8676 longer needed. Keeping those around slows down things linearly.
8677 Note that this never removes the current inferior. */
8684 signal_stop_state (int signo
)
8686 return signal_stop
[signo
];
8690 signal_print_state (int signo
)
8692 return signal_print
[signo
];
8696 signal_pass_state (int signo
)
8698 return signal_program
[signo
];
8702 signal_cache_update (int signo
)
8706 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
8707 signal_cache_update (signo
);
8712 signal_pass
[signo
] = (signal_stop
[signo
] == 0
8713 && signal_print
[signo
] == 0
8714 && signal_program
[signo
] == 1
8715 && signal_catch
[signo
] == 0);
8719 signal_stop_update (int signo
, int state
)
8721 int ret
= signal_stop
[signo
];
8723 signal_stop
[signo
] = state
;
8724 signal_cache_update (signo
);
8729 signal_print_update (int signo
, int state
)
8731 int ret
= signal_print
[signo
];
8733 signal_print
[signo
] = state
;
8734 signal_cache_update (signo
);
8739 signal_pass_update (int signo
, int state
)
8741 int ret
= signal_program
[signo
];
8743 signal_program
[signo
] = state
;
8744 signal_cache_update (signo
);
8748 /* Update the global 'signal_catch' from INFO and notify the
8752 signal_catch_update (const unsigned int *info
)
8756 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
8757 signal_catch
[i
] = info
[i
] > 0;
8758 signal_cache_update (-1);
8759 target_pass_signals (signal_pass
);
8763 sig_print_header (void)
8765 printf_filtered (_("Signal Stop\tPrint\tPass "
8766 "to program\tDescription\n"));
8770 sig_print_info (enum gdb_signal oursig
)
8772 const char *name
= gdb_signal_to_name (oursig
);
8773 int name_padding
= 13 - strlen (name
);
8775 if (name_padding
<= 0)
8778 printf_filtered ("%s", name
);
8779 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
8780 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
8781 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
8782 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
8783 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
8786 /* Specify how various signals in the inferior should be handled. */
8789 handle_command (const char *args
, int from_tty
)
8791 int digits
, wordlen
;
8792 int sigfirst
, siglast
;
8793 enum gdb_signal oursig
;
8798 error_no_arg (_("signal to handle"));
8801 /* Allocate and zero an array of flags for which signals to handle. */
8803 const size_t nsigs
= GDB_SIGNAL_LAST
;
8804 unsigned char sigs
[nsigs
] {};
8806 /* Break the command line up into args. */
8808 gdb_argv
built_argv (args
);
8810 /* Walk through the args, looking for signal oursigs, signal names, and
8811 actions. Signal numbers and signal names may be interspersed with
8812 actions, with the actions being performed for all signals cumulatively
8813 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8815 for (char *arg
: built_argv
)
8817 wordlen
= strlen (arg
);
8818 for (digits
= 0; isdigit (arg
[digits
]); digits
++)
8822 sigfirst
= siglast
= -1;
8824 if (wordlen
>= 1 && !strncmp (arg
, "all", wordlen
))
8826 /* Apply action to all signals except those used by the
8827 debugger. Silently skip those. */
8830 siglast
= nsigs
- 1;
8832 else if (wordlen
>= 1 && !strncmp (arg
, "stop", wordlen
))
8834 SET_SIGS (nsigs
, sigs
, signal_stop
);
8835 SET_SIGS (nsigs
, sigs
, signal_print
);
8837 else if (wordlen
>= 1 && !strncmp (arg
, "ignore", wordlen
))
8839 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8841 else if (wordlen
>= 2 && !strncmp (arg
, "print", wordlen
))
8843 SET_SIGS (nsigs
, sigs
, signal_print
);
8845 else if (wordlen
>= 2 && !strncmp (arg
, "pass", wordlen
))
8847 SET_SIGS (nsigs
, sigs
, signal_program
);
8849 else if (wordlen
>= 3 && !strncmp (arg
, "nostop", wordlen
))
8851 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8853 else if (wordlen
>= 3 && !strncmp (arg
, "noignore", wordlen
))
8855 SET_SIGS (nsigs
, sigs
, signal_program
);
8857 else if (wordlen
>= 4 && !strncmp (arg
, "noprint", wordlen
))
8859 UNSET_SIGS (nsigs
, sigs
, signal_print
);
8860 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8862 else if (wordlen
>= 4 && !strncmp (arg
, "nopass", wordlen
))
8864 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8866 else if (digits
> 0)
8868 /* It is numeric. The numeric signal refers to our own
8869 internal signal numbering from target.h, not to host/target
8870 signal number. This is a feature; users really should be
8871 using symbolic names anyway, and the common ones like
8872 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8874 sigfirst
= siglast
= (int)
8875 gdb_signal_from_command (atoi (arg
));
8876 if (arg
[digits
] == '-')
8879 gdb_signal_from_command (atoi (arg
+ digits
+ 1));
8881 if (sigfirst
> siglast
)
8883 /* Bet he didn't figure we'd think of this case... */
8884 std::swap (sigfirst
, siglast
);
8889 oursig
= gdb_signal_from_name (arg
);
8890 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
8892 sigfirst
= siglast
= (int) oursig
;
8896 /* Not a number and not a recognized flag word => complain. */
8897 error (_("Unrecognized or ambiguous flag word: \"%s\"."), arg
);
8901 /* If any signal numbers or symbol names were found, set flags for
8902 which signals to apply actions to. */
8904 for (int signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
8906 switch ((enum gdb_signal
) signum
)
8908 case GDB_SIGNAL_TRAP
:
8909 case GDB_SIGNAL_INT
:
8910 if (!allsigs
&& !sigs
[signum
])
8912 if (query (_("%s is used by the debugger.\n\
8913 Are you sure you want to change it? "),
8914 gdb_signal_to_name ((enum gdb_signal
) signum
)))
8919 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8923 case GDB_SIGNAL_DEFAULT
:
8924 case GDB_SIGNAL_UNKNOWN
:
8925 /* Make sure that "all" doesn't print these. */
8934 for (int signum
= 0; signum
< nsigs
; signum
++)
8937 signal_cache_update (-1);
8938 target_pass_signals (signal_pass
);
8939 target_program_signals (signal_program
);
8943 /* Show the results. */
8944 sig_print_header ();
8945 for (; signum
< nsigs
; signum
++)
8947 sig_print_info ((enum gdb_signal
) signum
);
8954 /* Complete the "handle" command. */
8957 handle_completer (struct cmd_list_element
*ignore
,
8958 completion_tracker
&tracker
,
8959 const char *text
, const char *word
)
8961 static const char * const keywords
[] =
8975 signal_completer (ignore
, tracker
, text
, word
);
8976 complete_on_enum (tracker
, keywords
, word
, word
);
8980 gdb_signal_from_command (int num
)
8982 if (num
>= 1 && num
<= 15)
8983 return (enum gdb_signal
) num
;
8984 error (_("Only signals 1-15 are valid as numeric signals.\n\
8985 Use \"info signals\" for a list of symbolic signals."));
8988 /* Print current contents of the tables set by the handle command.
8989 It is possible we should just be printing signals actually used
8990 by the current target (but for things to work right when switching
8991 targets, all signals should be in the signal tables). */
8994 info_signals_command (const char *signum_exp
, int from_tty
)
8996 enum gdb_signal oursig
;
8998 sig_print_header ();
9002 /* First see if this is a symbol name. */
9003 oursig
= gdb_signal_from_name (signum_exp
);
9004 if (oursig
== GDB_SIGNAL_UNKNOWN
)
9006 /* No, try numeric. */
9008 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
9010 sig_print_info (oursig
);
9014 printf_filtered ("\n");
9015 /* These ugly casts brought to you by the native VAX compiler. */
9016 for (oursig
= GDB_SIGNAL_FIRST
;
9017 (int) oursig
< (int) GDB_SIGNAL_LAST
;
9018 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
9022 if (oursig
!= GDB_SIGNAL_UNKNOWN
9023 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
9024 sig_print_info (oursig
);
9027 printf_filtered (_("\nUse the \"handle\" command "
9028 "to change these tables.\n"));
9031 /* The $_siginfo convenience variable is a bit special. We don't know
9032 for sure the type of the value until we actually have a chance to
9033 fetch the data. The type can change depending on gdbarch, so it is
9034 also dependent on which thread you have selected.
9036 1. making $_siginfo be an internalvar that creates a new value on
9039 2. making the value of $_siginfo be an lval_computed value. */
9041 /* This function implements the lval_computed support for reading a
9045 siginfo_value_read (struct value
*v
)
9047 LONGEST transferred
;
9049 /* If we can access registers, so can we access $_siginfo. Likewise
9051 validate_registers_access ();
9054 target_read (current_inferior ()->top_target (),
9055 TARGET_OBJECT_SIGNAL_INFO
,
9057 value_contents_all_raw (v
),
9059 TYPE_LENGTH (value_type (v
)));
9061 if (transferred
!= TYPE_LENGTH (value_type (v
)))
9062 error (_("Unable to read siginfo"));
9065 /* This function implements the lval_computed support for writing a
9069 siginfo_value_write (struct value
*v
, struct value
*fromval
)
9071 LONGEST transferred
;
9073 /* If we can access registers, so can we access $_siginfo. Likewise
9075 validate_registers_access ();
9077 transferred
= target_write (current_inferior ()->top_target (),
9078 TARGET_OBJECT_SIGNAL_INFO
,
9080 value_contents_all_raw (fromval
),
9082 TYPE_LENGTH (value_type (fromval
)));
9084 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
9085 error (_("Unable to write siginfo"));
9088 static const struct lval_funcs siginfo_value_funcs
=
9094 /* Return a new value with the correct type for the siginfo object of
9095 the current thread using architecture GDBARCH. Return a void value
9096 if there's no object available. */
9098 static struct value
*
9099 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
9102 if (target_has_stack ()
9103 && inferior_ptid
!= null_ptid
9104 && gdbarch_get_siginfo_type_p (gdbarch
))
9106 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
9108 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
9111 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
9115 /* infcall_suspend_state contains state about the program itself like its
9116 registers and any signal it received when it last stopped.
9117 This state must be restored regardless of how the inferior function call
9118 ends (either successfully, or after it hits a breakpoint or signal)
9119 if the program is to properly continue where it left off. */
9121 class infcall_suspend_state
9124 /* Capture state from GDBARCH, TP, and REGCACHE that must be restored
9125 once the inferior function call has finished. */
9126 infcall_suspend_state (struct gdbarch
*gdbarch
,
9127 const struct thread_info
*tp
,
9128 struct regcache
*regcache
)
9129 : m_thread_suspend (tp
->suspend
),
9130 m_registers (new readonly_detached_regcache (*regcache
))
9132 gdb::unique_xmalloc_ptr
<gdb_byte
> siginfo_data
;
9134 if (gdbarch_get_siginfo_type_p (gdbarch
))
9136 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
9137 size_t len
= TYPE_LENGTH (type
);
9139 siginfo_data
.reset ((gdb_byte
*) xmalloc (len
));
9141 if (target_read (current_inferior ()->top_target (),
9142 TARGET_OBJECT_SIGNAL_INFO
, NULL
,
9143 siginfo_data
.get (), 0, len
) != len
)
9145 /* Errors ignored. */
9146 siginfo_data
.reset (nullptr);
9152 m_siginfo_gdbarch
= gdbarch
;
9153 m_siginfo_data
= std::move (siginfo_data
);
9157 /* Return a pointer to the stored register state. */
9159 readonly_detached_regcache
*registers () const
9161 return m_registers
.get ();
9164 /* Restores the stored state into GDBARCH, TP, and REGCACHE. */
9166 void restore (struct gdbarch
*gdbarch
,
9167 struct thread_info
*tp
,
9168 struct regcache
*regcache
) const
9170 tp
->suspend
= m_thread_suspend
;
9172 if (m_siginfo_gdbarch
== gdbarch
)
9174 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
9176 /* Errors ignored. */
9177 target_write (current_inferior ()->top_target (),
9178 TARGET_OBJECT_SIGNAL_INFO
, NULL
,
9179 m_siginfo_data
.get (), 0, TYPE_LENGTH (type
));
9182 /* The inferior can be gone if the user types "print exit(0)"
9183 (and perhaps other times). */
9184 if (target_has_execution ())
9185 /* NB: The register write goes through to the target. */
9186 regcache
->restore (registers ());
9190 /* How the current thread stopped before the inferior function call was
9192 struct thread_suspend_state m_thread_suspend
;
9194 /* The registers before the inferior function call was executed. */
9195 std::unique_ptr
<readonly_detached_regcache
> m_registers
;
9197 /* Format of SIGINFO_DATA or NULL if it is not present. */
9198 struct gdbarch
*m_siginfo_gdbarch
= nullptr;
9200 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
9201 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
9202 content would be invalid. */
9203 gdb::unique_xmalloc_ptr
<gdb_byte
> m_siginfo_data
;
9206 infcall_suspend_state_up
9207 save_infcall_suspend_state ()
9209 struct thread_info
*tp
= inferior_thread ();
9210 struct regcache
*regcache
= get_current_regcache ();
9211 struct gdbarch
*gdbarch
= regcache
->arch ();
9213 infcall_suspend_state_up inf_state
9214 (new struct infcall_suspend_state (gdbarch
, tp
, regcache
));
9216 /* Having saved the current state, adjust the thread state, discarding
9217 any stop signal information. The stop signal is not useful when
9218 starting an inferior function call, and run_inferior_call will not use
9219 the signal due to its `proceed' call with GDB_SIGNAL_0. */
9220 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
9225 /* Restore inferior session state to INF_STATE. */
9228 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
9230 struct thread_info
*tp
= inferior_thread ();
9231 struct regcache
*regcache
= get_current_regcache ();
9232 struct gdbarch
*gdbarch
= regcache
->arch ();
9234 inf_state
->restore (gdbarch
, tp
, regcache
);
9235 discard_infcall_suspend_state (inf_state
);
9239 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
9244 readonly_detached_regcache
*
9245 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
9247 return inf_state
->registers ();
9250 /* infcall_control_state contains state regarding gdb's control of the
9251 inferior itself like stepping control. It also contains session state like
9252 the user's currently selected frame. */
9254 struct infcall_control_state
9256 struct thread_control_state thread_control
;
9257 struct inferior_control_state inferior_control
;
9260 enum stop_stack_kind stop_stack_dummy
= STOP_NONE
;
9261 int stopped_by_random_signal
= 0;
9263 /* ID and level of the selected frame when the inferior function
9265 struct frame_id selected_frame_id
{};
9266 int selected_frame_level
= -1;
9269 /* Save all of the information associated with the inferior<==>gdb
9272 infcall_control_state_up
9273 save_infcall_control_state ()
9275 infcall_control_state_up
inf_status (new struct infcall_control_state
);
9276 struct thread_info
*tp
= inferior_thread ();
9277 struct inferior
*inf
= current_inferior ();
9279 inf_status
->thread_control
= tp
->control
;
9280 inf_status
->inferior_control
= inf
->control
;
9282 tp
->control
.step_resume_breakpoint
= NULL
;
9283 tp
->control
.exception_resume_breakpoint
= NULL
;
9285 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
9286 chain. If caller's caller is walking the chain, they'll be happier if we
9287 hand them back the original chain when restore_infcall_control_state is
9289 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
9292 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
9293 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
9295 save_selected_frame (&inf_status
->selected_frame_id
,
9296 &inf_status
->selected_frame_level
);
9301 /* Restore inferior session state to INF_STATUS. */
9304 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
9306 struct thread_info
*tp
= inferior_thread ();
9307 struct inferior
*inf
= current_inferior ();
9309 if (tp
->control
.step_resume_breakpoint
)
9310 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
9312 if (tp
->control
.exception_resume_breakpoint
)
9313 tp
->control
.exception_resume_breakpoint
->disposition
9314 = disp_del_at_next_stop
;
9316 /* Handle the bpstat_copy of the chain. */
9317 bpstat_clear (&tp
->control
.stop_bpstat
);
9319 tp
->control
= inf_status
->thread_control
;
9320 inf
->control
= inf_status
->inferior_control
;
9323 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
9324 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
9326 if (target_has_stack ())
9328 restore_selected_frame (inf_status
->selected_frame_id
,
9329 inf_status
->selected_frame_level
);
9336 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
9338 if (inf_status
->thread_control
.step_resume_breakpoint
)
9339 inf_status
->thread_control
.step_resume_breakpoint
->disposition
9340 = disp_del_at_next_stop
;
9342 if (inf_status
->thread_control
.exception_resume_breakpoint
)
9343 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
9344 = disp_del_at_next_stop
;
9346 /* See save_infcall_control_state for info on stop_bpstat. */
9347 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
9355 clear_exit_convenience_vars (void)
9357 clear_internalvar (lookup_internalvar ("_exitsignal"));
9358 clear_internalvar (lookup_internalvar ("_exitcode"));
9362 /* User interface for reverse debugging:
9363 Set exec-direction / show exec-direction commands
9364 (returns error unless target implements to_set_exec_direction method). */
9366 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
9367 static const char exec_forward
[] = "forward";
9368 static const char exec_reverse
[] = "reverse";
9369 static const char *exec_direction
= exec_forward
;
9370 static const char *const exec_direction_names
[] = {
9377 set_exec_direction_func (const char *args
, int from_tty
,
9378 struct cmd_list_element
*cmd
)
9380 if (target_can_execute_reverse ())
9382 if (!strcmp (exec_direction
, exec_forward
))
9383 execution_direction
= EXEC_FORWARD
;
9384 else if (!strcmp (exec_direction
, exec_reverse
))
9385 execution_direction
= EXEC_REVERSE
;
9389 exec_direction
= exec_forward
;
9390 error (_("Target does not support this operation."));
9395 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
9396 struct cmd_list_element
*cmd
, const char *value
)
9398 switch (execution_direction
) {
9400 fprintf_filtered (out
, _("Forward.\n"));
9403 fprintf_filtered (out
, _("Reverse.\n"));
9406 internal_error (__FILE__
, __LINE__
,
9407 _("bogus execution_direction value: %d"),
9408 (int) execution_direction
);
9413 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
9414 struct cmd_list_element
*c
, const char *value
)
9416 fprintf_filtered (file
, _("Resuming the execution of threads "
9417 "of all processes is %s.\n"), value
);
9420 /* Implementation of `siginfo' variable. */
9422 static const struct internalvar_funcs siginfo_funcs
=
9429 /* Callback for infrun's target events source. This is marked when a
9430 thread has a pending status to process. */
9433 infrun_async_inferior_event_handler (gdb_client_data data
)
9435 clear_async_event_handler (infrun_async_inferior_event_token
);
9436 inferior_event_handler (INF_REG_EVENT
);
9443 /* Verify that when two threads with the same ptid exist (from two different
9444 targets) and one of them changes ptid, we only update inferior_ptid if
9445 it is appropriate. */
9448 infrun_thread_ptid_changed ()
9450 gdbarch
*arch
= current_inferior ()->gdbarch
;
9452 /* The thread which inferior_ptid represents changes ptid. */
9454 scoped_restore_current_pspace_and_thread restore
;
9456 scoped_mock_context
<test_target_ops
> target1 (arch
);
9457 scoped_mock_context
<test_target_ops
> target2 (arch
);
9458 target2
.mock_inferior
.next
= &target1
.mock_inferior
;
9460 ptid_t
old_ptid (111, 222);
9461 ptid_t
new_ptid (111, 333);
9463 target1
.mock_inferior
.pid
= old_ptid
.pid ();
9464 target1
.mock_thread
.ptid
= old_ptid
;
9465 target2
.mock_inferior
.pid
= old_ptid
.pid ();
9466 target2
.mock_thread
.ptid
= old_ptid
;
9468 auto restore_inferior_ptid
= make_scoped_restore (&inferior_ptid
, old_ptid
);
9469 set_current_inferior (&target1
.mock_inferior
);
9471 thread_change_ptid (&target1
.mock_target
, old_ptid
, new_ptid
);
9473 gdb_assert (inferior_ptid
== new_ptid
);
9476 /* A thread with the same ptid as inferior_ptid, but from another target,
9479 scoped_restore_current_pspace_and_thread restore
;
9481 scoped_mock_context
<test_target_ops
> target1 (arch
);
9482 scoped_mock_context
<test_target_ops
> target2 (arch
);
9483 target2
.mock_inferior
.next
= &target1
.mock_inferior
;
9485 ptid_t
old_ptid (111, 222);
9486 ptid_t
new_ptid (111, 333);
9488 target1
.mock_inferior
.pid
= old_ptid
.pid ();
9489 target1
.mock_thread
.ptid
= old_ptid
;
9490 target2
.mock_inferior
.pid
= old_ptid
.pid ();
9491 target2
.mock_thread
.ptid
= old_ptid
;
9493 auto restore_inferior_ptid
= make_scoped_restore (&inferior_ptid
, old_ptid
);
9494 set_current_inferior (&target2
.mock_inferior
);
9496 thread_change_ptid (&target1
.mock_target
, old_ptid
, new_ptid
);
9498 gdb_assert (inferior_ptid
== old_ptid
);
9502 } /* namespace selftests */
9504 #endif /* GDB_SELF_TEST */
9506 void _initialize_infrun ();
9508 _initialize_infrun ()
9510 struct cmd_list_element
*c
;
9512 /* Register extra event sources in the event loop. */
9513 infrun_async_inferior_event_token
9514 = create_async_event_handler (infrun_async_inferior_event_handler
, NULL
,
9517 cmd_list_element
*info_signals_cmd
9518 = add_info ("signals", info_signals_command
, _("\
9519 What debugger does when program gets various signals.\n\
9520 Specify a signal as argument to print info on that signal only."));
9521 add_info_alias ("handle", info_signals_cmd
, 0);
9523 c
= add_com ("handle", class_run
, handle_command
, _("\
9524 Specify how to handle signals.\n\
9525 Usage: handle SIGNAL [ACTIONS]\n\
9526 Args are signals and actions to apply to those signals.\n\
9527 If no actions are specified, the current settings for the specified signals\n\
9528 will be displayed instead.\n\
9530 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
9531 from 1-15 are allowed for compatibility with old versions of GDB.\n\
9532 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
9533 The special arg \"all\" is recognized to mean all signals except those\n\
9534 used by the debugger, typically SIGTRAP and SIGINT.\n\
9536 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
9537 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
9538 Stop means reenter debugger if this signal happens (implies print).\n\
9539 Print means print a message if this signal happens.\n\
9540 Pass means let program see this signal; otherwise program doesn't know.\n\
9541 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
9542 Pass and Stop may be combined.\n\
9544 Multiple signals may be specified. Signal numbers and signal names\n\
9545 may be interspersed with actions, with the actions being performed for\n\
9546 all signals cumulatively specified."));
9547 set_cmd_completer (c
, handle_completer
);
9550 stop_command
= add_cmd ("stop", class_obscure
,
9551 not_just_help_class_command
, _("\
9552 There is no `stop' command, but you can set a hook on `stop'.\n\
9553 This allows you to set a list of commands to be run each time execution\n\
9554 of the program stops."), &cmdlist
);
9556 add_setshow_boolean_cmd
9557 ("infrun", class_maintenance
, &debug_infrun
,
9558 _("Set inferior debugging."),
9559 _("Show inferior debugging."),
9560 _("When non-zero, inferior specific debugging is enabled."),
9561 NULL
, show_debug_infrun
, &setdebuglist
, &showdebuglist
);
9563 add_setshow_boolean_cmd ("non-stop", no_class
,
9565 Set whether gdb controls the inferior in non-stop mode."), _("\
9566 Show whether gdb controls the inferior in non-stop mode."), _("\
9567 When debugging a multi-threaded program and this setting is\n\
9568 off (the default, also called all-stop mode), when one thread stops\n\
9569 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9570 all other threads in the program while you interact with the thread of\n\
9571 interest. When you continue or step a thread, you can allow the other\n\
9572 threads to run, or have them remain stopped, but while you inspect any\n\
9573 thread's state, all threads stop.\n\
9575 In non-stop mode, when one thread stops, other threads can continue\n\
9576 to run freely. You'll be able to step each thread independently,\n\
9577 leave it stopped or free to run as needed."),
9583 for (size_t i
= 0; i
< GDB_SIGNAL_LAST
; i
++)
9586 signal_print
[i
] = 1;
9587 signal_program
[i
] = 1;
9588 signal_catch
[i
] = 0;
9591 /* Signals caused by debugger's own actions should not be given to
9592 the program afterwards.
9594 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9595 explicitly specifies that it should be delivered to the target
9596 program. Typically, that would occur when a user is debugging a
9597 target monitor on a simulator: the target monitor sets a
9598 breakpoint; the simulator encounters this breakpoint and halts
9599 the simulation handing control to GDB; GDB, noting that the stop
9600 address doesn't map to any known breakpoint, returns control back
9601 to the simulator; the simulator then delivers the hardware
9602 equivalent of a GDB_SIGNAL_TRAP to the program being
9604 signal_program
[GDB_SIGNAL_TRAP
] = 0;
9605 signal_program
[GDB_SIGNAL_INT
] = 0;
9607 /* Signals that are not errors should not normally enter the debugger. */
9608 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
9609 signal_print
[GDB_SIGNAL_ALRM
] = 0;
9610 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
9611 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
9612 signal_stop
[GDB_SIGNAL_PROF
] = 0;
9613 signal_print
[GDB_SIGNAL_PROF
] = 0;
9614 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
9615 signal_print
[GDB_SIGNAL_CHLD
] = 0;
9616 signal_stop
[GDB_SIGNAL_IO
] = 0;
9617 signal_print
[GDB_SIGNAL_IO
] = 0;
9618 signal_stop
[GDB_SIGNAL_POLL
] = 0;
9619 signal_print
[GDB_SIGNAL_POLL
] = 0;
9620 signal_stop
[GDB_SIGNAL_URG
] = 0;
9621 signal_print
[GDB_SIGNAL_URG
] = 0;
9622 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
9623 signal_print
[GDB_SIGNAL_WINCH
] = 0;
9624 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
9625 signal_print
[GDB_SIGNAL_PRIO
] = 0;
9627 /* These signals are used internally by user-level thread
9628 implementations. (See signal(5) on Solaris.) Like the above
9629 signals, a healthy program receives and handles them as part of
9630 its normal operation. */
9631 signal_stop
[GDB_SIGNAL_LWP
] = 0;
9632 signal_print
[GDB_SIGNAL_LWP
] = 0;
9633 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
9634 signal_print
[GDB_SIGNAL_WAITING
] = 0;
9635 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
9636 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
9637 signal_stop
[GDB_SIGNAL_LIBRT
] = 0;
9638 signal_print
[GDB_SIGNAL_LIBRT
] = 0;
9640 /* Update cached state. */
9641 signal_cache_update (-1);
9643 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
9644 &stop_on_solib_events
, _("\
9645 Set stopping for shared library events."), _("\
9646 Show stopping for shared library events."), _("\
9647 If nonzero, gdb will give control to the user when the dynamic linker\n\
9648 notifies gdb of shared library events. The most common event of interest\n\
9649 to the user would be loading/unloading of a new library."),
9650 set_stop_on_solib_events
,
9651 show_stop_on_solib_events
,
9652 &setlist
, &showlist
);
9654 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
9655 follow_fork_mode_kind_names
,
9656 &follow_fork_mode_string
, _("\
9657 Set debugger response to a program call of fork or vfork."), _("\
9658 Show debugger response to a program call of fork or vfork."), _("\
9659 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9660 parent - the original process is debugged after a fork\n\
9661 child - the new process is debugged after a fork\n\
9662 The unfollowed process will continue to run.\n\
9663 By default, the debugger will follow the parent process."),
9665 show_follow_fork_mode_string
,
9666 &setlist
, &showlist
);
9668 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
9669 follow_exec_mode_names
,
9670 &follow_exec_mode_string
, _("\
9671 Set debugger response to a program call of exec."), _("\
9672 Show debugger response to a program call of exec."), _("\
9673 An exec call replaces the program image of a process.\n\
9675 follow-exec-mode can be:\n\
9677 new - the debugger creates a new inferior and rebinds the process\n\
9678 to this new inferior. The program the process was running before\n\
9679 the exec call can be restarted afterwards by restarting the original\n\
9682 same - the debugger keeps the process bound to the same inferior.\n\
9683 The new executable image replaces the previous executable loaded in\n\
9684 the inferior. Restarting the inferior after the exec call restarts\n\
9685 the executable the process was running after the exec call.\n\
9687 By default, the debugger will use the same inferior."),
9689 show_follow_exec_mode_string
,
9690 &setlist
, &showlist
);
9692 add_setshow_enum_cmd ("scheduler-locking", class_run
,
9693 scheduler_enums
, &scheduler_mode
, _("\
9694 Set mode for locking scheduler during execution."), _("\
9695 Show mode for locking scheduler during execution."), _("\
9696 off == no locking (threads may preempt at any time)\n\
9697 on == full locking (no thread except the current thread may run)\n\
9698 This applies to both normal execution and replay mode.\n\
9699 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9700 In this mode, other threads may run during other commands.\n\
9701 This applies to both normal execution and replay mode.\n\
9702 replay == scheduler locked in replay mode and unlocked during normal execution."),
9703 set_schedlock_func
, /* traps on target vector */
9704 show_scheduler_mode
,
9705 &setlist
, &showlist
);
9707 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
9708 Set mode for resuming threads of all processes."), _("\
9709 Show mode for resuming threads of all processes."), _("\
9710 When on, execution commands (such as 'continue' or 'next') resume all\n\
9711 threads of all processes. When off (which is the default), execution\n\
9712 commands only resume the threads of the current process. The set of\n\
9713 threads that are resumed is further refined by the scheduler-locking\n\
9714 mode (see help set scheduler-locking)."),
9716 show_schedule_multiple
,
9717 &setlist
, &showlist
);
9719 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
9720 Set mode of the step operation."), _("\
9721 Show mode of the step operation."), _("\
9722 When set, doing a step over a function without debug line information\n\
9723 will stop at the first instruction of that function. Otherwise, the\n\
9724 function is skipped and the step command stops at a different source line."),
9726 show_step_stop_if_no_debug
,
9727 &setlist
, &showlist
);
9729 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
9730 &can_use_displaced_stepping
, _("\
9731 Set debugger's willingness to use displaced stepping."), _("\
9732 Show debugger's willingness to use displaced stepping."), _("\
9733 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9734 supported by the target architecture. If off, gdb will not use displaced\n\
9735 stepping to step over breakpoints, even if such is supported by the target\n\
9736 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9737 if the target architecture supports it and non-stop mode is active, but will not\n\
9738 use it in all-stop mode (see help set non-stop)."),
9740 show_can_use_displaced_stepping
,
9741 &setlist
, &showlist
);
9743 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
9744 &exec_direction
, _("Set direction of execution.\n\
9745 Options are 'forward' or 'reverse'."),
9746 _("Show direction of execution (forward/reverse)."),
9747 _("Tells gdb whether to execute forward or backward."),
9748 set_exec_direction_func
, show_exec_direction_func
,
9749 &setlist
, &showlist
);
9751 /* Set/show detach-on-fork: user-settable mode. */
9753 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
9754 Set whether gdb will detach the child of a fork."), _("\
9755 Show whether gdb will detach the child of a fork."), _("\
9756 Tells gdb whether to detach the child of a fork."),
9757 NULL
, NULL
, &setlist
, &showlist
);
9759 /* Set/show disable address space randomization mode. */
9761 add_setshow_boolean_cmd ("disable-randomization", class_support
,
9762 &disable_randomization
, _("\
9763 Set disabling of debuggee's virtual address space randomization."), _("\
9764 Show disabling of debuggee's virtual address space randomization."), _("\
9765 When this mode is on (which is the default), randomization of the virtual\n\
9766 address space is disabled. Standalone programs run with the randomization\n\
9767 enabled by default on some platforms."),
9768 &set_disable_randomization
,
9769 &show_disable_randomization
,
9770 &setlist
, &showlist
);
9772 /* ptid initializations */
9773 inferior_ptid
= null_ptid
;
9774 target_last_wait_ptid
= minus_one_ptid
;
9776 gdb::observers::thread_ptid_changed
.attach (infrun_thread_ptid_changed
,
9778 gdb::observers::thread_stop_requested
.attach (infrun_thread_stop_requested
,
9780 gdb::observers::thread_exit
.attach (infrun_thread_thread_exit
, "infrun");
9781 gdb::observers::inferior_exit
.attach (infrun_inferior_exit
, "infrun");
9782 gdb::observers::inferior_execd
.attach (infrun_inferior_execd
, "infrun");
9784 /* Explicitly create without lookup, since that tries to create a
9785 value with a void typed value, and when we get here, gdbarch
9786 isn't initialized yet. At this point, we're quite sure there
9787 isn't another convenience variable of the same name. */
9788 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
9790 add_setshow_boolean_cmd ("observer", no_class
,
9791 &observer_mode_1
, _("\
9792 Set whether gdb controls the inferior in observer mode."), _("\
9793 Show whether gdb controls the inferior in observer mode."), _("\
9794 In observer mode, GDB can get data from the inferior, but not\n\
9795 affect its execution. Registers and memory may not be changed,\n\
9796 breakpoints may not be set, and the program cannot be interrupted\n\
9804 selftests::register_test ("infrun_thread_ptid_changed",
9805 selftests::infrun_thread_ptid_changed
);