1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2022 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
->thread_waiting_for_vfork_done
545 = detach_fork
? inferior_thread () : nullptr;
546 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
551 /* Follow the child. */
552 struct inferior
*parent_inf
, *child_inf
;
553 struct program_space
*parent_pspace
;
555 if (print_inferior_events
)
557 std::string parent_pid
= target_pid_to_str (parent_ptid
);
558 std::string child_pid
= target_pid_to_str (child_ptid
);
560 target_terminal::ours_for_output ();
561 fprintf_filtered (gdb_stdlog
,
562 _("[Attaching after %s %s to child %s]\n"),
564 has_vforked
? "vfork" : "fork",
568 /* Add the new inferior first, so that the target_detach below
569 doesn't unpush the target. */
571 child_inf
= add_inferior (child_ptid
.pid ());
573 parent_inf
= current_inferior ();
574 child_inf
->attach_flag
= parent_inf
->attach_flag
;
575 copy_terminal_info (child_inf
, parent_inf
);
576 child_inf
->gdbarch
= parent_inf
->gdbarch
;
577 copy_inferior_target_desc_info (child_inf
, parent_inf
);
579 parent_pspace
= parent_inf
->pspace
;
581 process_stratum_target
*target
= parent_inf
->process_target ();
584 /* Hold a strong reference to the target while (maybe)
585 detaching the parent. Otherwise detaching could close the
587 auto target_ref
= target_ops_ref::new_reference (target
);
589 /* If we're vforking, we want to hold on to the parent until
590 the child exits or execs. At child exec or exit time we
591 can remove the old breakpoints from the parent and detach
592 or resume debugging it. Otherwise, detach the parent now;
593 we'll want to reuse it's program/address spaces, but we
594 can't set them to the child before removing breakpoints
595 from the parent, otherwise, the breakpoints module could
596 decide to remove breakpoints from the wrong process (since
597 they'd be assigned to the same address space). */
601 gdb_assert (child_inf
->vfork_parent
== NULL
);
602 gdb_assert (parent_inf
->vfork_child
== NULL
);
603 child_inf
->vfork_parent
= parent_inf
;
604 child_inf
->pending_detach
= 0;
605 parent_inf
->vfork_child
= child_inf
;
606 parent_inf
->pending_detach
= detach_fork
;
607 parent_inf
->thread_waiting_for_vfork_done
= nullptr;
609 else if (detach_fork
)
611 if (print_inferior_events
)
613 /* Ensure that we have a process ptid. */
614 ptid_t process_ptid
= ptid_t (parent_ptid
.pid ());
616 target_terminal::ours_for_output ();
617 fprintf_filtered (gdb_stdlog
,
618 _("[Detaching after fork from "
620 target_pid_to_str (process_ptid
).c_str ());
623 target_detach (parent_inf
, 0);
627 /* Note that the detach above makes PARENT_INF dangling. */
629 /* Add the child thread to the appropriate lists, and switch
630 to this new thread, before cloning the program space, and
631 informing the solib layer about this new process. */
633 set_current_inferior (child_inf
);
634 child_inf
->push_target (target
);
637 thread_info
*child_thr
= add_thread_silent (target
, child_ptid
);
639 /* If this is a vfork child, then the address-space is shared
640 with the parent. If we detached from the parent, then we can
641 reuse the parent's program/address spaces. */
642 if (has_vforked
|| detach_fork
)
644 child_inf
->pspace
= parent_pspace
;
645 child_inf
->aspace
= child_inf
->pspace
->aspace
;
651 child_inf
->aspace
= new_address_space ();
652 child_inf
->pspace
= new program_space (child_inf
->aspace
);
653 child_inf
->removable
= 1;
654 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
655 set_current_program_space (child_inf
->pspace
);
656 clone_program_space (child_inf
->pspace
, parent_pspace
);
658 /* Let the shared library layer (e.g., solib-svr4) learn
659 about this new process, relocate the cloned exec, pull in
660 shared libraries, and install the solib event breakpoint.
661 If a "cloned-VM" event was propagated better throughout
662 the core, this wouldn't be required. */
663 scoped_restore restore_in_initial_library_scan
664 = make_scoped_restore (&child_inf
->in_initial_library_scan
, true);
665 solib_create_inferior_hook (0);
668 switch_to_thread (child_thr
);
671 target_follow_fork (follow_child
, detach_fork
);
676 /* Tell the target to follow the fork we're stopped at. Returns true
677 if the inferior should be resumed; false, if the target for some
678 reason decided it's best not to resume. */
683 bool follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
684 bool should_resume
= true;
685 struct thread_info
*tp
;
687 /* Copy user stepping state to the new inferior thread. FIXME: the
688 followed fork child thread should have a copy of most of the
689 parent thread structure's run control related fields, not just these.
690 Initialized to avoid "may be used uninitialized" warnings from gcc. */
691 struct breakpoint
*step_resume_breakpoint
= NULL
;
692 struct breakpoint
*exception_resume_breakpoint
= NULL
;
693 CORE_ADDR step_range_start
= 0;
694 CORE_ADDR step_range_end
= 0;
695 int current_line
= 0;
696 symtab
*current_symtab
= NULL
;
697 struct frame_id step_frame_id
= { 0 };
698 struct thread_fsm
*thread_fsm
= NULL
;
702 process_stratum_target
*wait_target
;
704 struct target_waitstatus wait_status
;
706 /* Get the last target status returned by target_wait(). */
707 get_last_target_status (&wait_target
, &wait_ptid
, &wait_status
);
709 /* If not stopped at a fork event, then there's nothing else to
711 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
712 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
715 /* Check if we switched over from WAIT_PTID, since the event was
717 if (wait_ptid
!= minus_one_ptid
718 && (current_inferior ()->process_target () != wait_target
719 || inferior_ptid
!= wait_ptid
))
721 /* We did. Switch back to WAIT_PTID thread, to tell the
722 target to follow it (in either direction). We'll
723 afterwards refuse to resume, and inform the user what
725 thread_info
*wait_thread
= find_thread_ptid (wait_target
, wait_ptid
);
726 switch_to_thread (wait_thread
);
727 should_resume
= false;
731 tp
= inferior_thread ();
733 /* If there were any forks/vforks that were caught and are now to be
734 followed, then do so now. */
735 switch (tp
->pending_follow
.kind
)
737 case TARGET_WAITKIND_FORKED
:
738 case TARGET_WAITKIND_VFORKED
:
740 ptid_t parent
, child
;
742 /* If the user did a next/step, etc, over a fork call,
743 preserve the stepping state in the fork child. */
744 if (follow_child
&& should_resume
)
746 step_resume_breakpoint
= clone_momentary_breakpoint
747 (tp
->control
.step_resume_breakpoint
);
748 step_range_start
= tp
->control
.step_range_start
;
749 step_range_end
= tp
->control
.step_range_end
;
750 current_line
= tp
->current_line
;
751 current_symtab
= tp
->current_symtab
;
752 step_frame_id
= tp
->control
.step_frame_id
;
753 exception_resume_breakpoint
754 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
755 thread_fsm
= tp
->thread_fsm
;
757 /* For now, delete the parent's sr breakpoint, otherwise,
758 parent/child sr breakpoints are considered duplicates,
759 and the child version will not be installed. Remove
760 this when the breakpoints module becomes aware of
761 inferiors and address spaces. */
762 delete_step_resume_breakpoint (tp
);
763 tp
->control
.step_range_start
= 0;
764 tp
->control
.step_range_end
= 0;
765 tp
->control
.step_frame_id
= null_frame_id
;
766 delete_exception_resume_breakpoint (tp
);
767 tp
->thread_fsm
= NULL
;
770 parent
= inferior_ptid
;
771 child
= tp
->pending_follow
.value
.related_pid
;
773 process_stratum_target
*parent_targ
= tp
->inf
->process_target ();
774 /* Set up inferior(s) as specified by the caller, and tell the
775 target to do whatever is necessary to follow either parent
777 if (follow_fork_inferior (follow_child
, detach_fork
))
779 /* Target refused to follow, or there's some other reason
780 we shouldn't resume. */
785 /* This pending follow fork event is now handled, one way
786 or another. The previous selected thread may be gone
787 from the lists by now, but if it is still around, need
788 to clear the pending follow request. */
789 tp
= find_thread_ptid (parent_targ
, parent
);
791 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
793 /* This makes sure we don't try to apply the "Switched
794 over from WAIT_PID" logic above. */
795 nullify_last_target_wait_ptid ();
797 /* If we followed the child, switch to it... */
800 thread_info
*child_thr
= find_thread_ptid (parent_targ
, child
);
801 switch_to_thread (child_thr
);
803 /* ... and preserve the stepping state, in case the
804 user was stepping over the fork call. */
807 tp
= inferior_thread ();
808 tp
->control
.step_resume_breakpoint
809 = step_resume_breakpoint
;
810 tp
->control
.step_range_start
= step_range_start
;
811 tp
->control
.step_range_end
= step_range_end
;
812 tp
->current_line
= current_line
;
813 tp
->current_symtab
= current_symtab
;
814 tp
->control
.step_frame_id
= step_frame_id
;
815 tp
->control
.exception_resume_breakpoint
816 = exception_resume_breakpoint
;
817 tp
->thread_fsm
= thread_fsm
;
821 /* If we get here, it was because we're trying to
822 resume from a fork catchpoint, but, the user
823 has switched threads away from the thread that
824 forked. In that case, the resume command
825 issued is most likely not applicable to the
826 child, so just warn, and refuse to resume. */
827 warning (_("Not resuming: switched threads "
828 "before following fork child."));
831 /* Reset breakpoints in the child as appropriate. */
832 follow_inferior_reset_breakpoints ();
837 case TARGET_WAITKIND_SPURIOUS
:
838 /* Nothing to follow. */
841 internal_error (__FILE__
, __LINE__
,
842 "Unexpected pending_follow.kind %d\n",
843 tp
->pending_follow
.kind
);
847 return should_resume
;
851 follow_inferior_reset_breakpoints (void)
853 struct thread_info
*tp
= inferior_thread ();
855 /* Was there a step_resume breakpoint? (There was if the user
856 did a "next" at the fork() call.) If so, explicitly reset its
857 thread number. Cloned step_resume breakpoints are disabled on
858 creation, so enable it here now that it is associated with the
861 step_resumes are a form of bp that are made to be per-thread.
862 Since we created the step_resume bp when the parent process
863 was being debugged, and now are switching to the child process,
864 from the breakpoint package's viewpoint, that's a switch of
865 "threads". We must update the bp's notion of which thread
866 it is for, or it'll be ignored when it triggers. */
868 if (tp
->control
.step_resume_breakpoint
)
870 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
871 tp
->control
.step_resume_breakpoint
->loc
->enabled
= 1;
874 /* Treat exception_resume breakpoints like step_resume breakpoints. */
875 if (tp
->control
.exception_resume_breakpoint
)
877 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
878 tp
->control
.exception_resume_breakpoint
->loc
->enabled
= 1;
881 /* Reinsert all breakpoints in the child. The user may have set
882 breakpoints after catching the fork, in which case those
883 were never set in the child, but only in the parent. This makes
884 sure the inserted breakpoints match the breakpoint list. */
886 breakpoint_re_set ();
887 insert_breakpoints ();
890 /* The child has exited or execed: resume threads of the parent the
891 user wanted to be executing. */
894 proceed_after_vfork_done (struct thread_info
*thread
,
897 int pid
= * (int *) arg
;
899 if (thread
->ptid
.pid () == pid
900 && thread
->state
== THREAD_RUNNING
901 && !thread
->executing
902 && !thread
->stop_requested
903 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
905 infrun_debug_printf ("resuming vfork parent thread %s",
906 target_pid_to_str (thread
->ptid
).c_str ());
908 switch_to_thread (thread
);
909 clear_proceed_status (0);
910 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
);
916 /* Called whenever we notice an exec or exit event, to handle
917 detaching or resuming a vfork parent. */
920 handle_vfork_child_exec_or_exit (int exec
)
922 struct inferior
*inf
= current_inferior ();
924 if (inf
->vfork_parent
)
926 int resume_parent
= -1;
928 /* This exec or exit marks the end of the shared memory region
929 between the parent and the child. Break the bonds. */
930 inferior
*vfork_parent
= inf
->vfork_parent
;
931 inf
->vfork_parent
->vfork_child
= NULL
;
932 inf
->vfork_parent
= NULL
;
934 /* If the user wanted to detach from the parent, now is the
936 if (vfork_parent
->pending_detach
)
938 struct program_space
*pspace
;
939 struct address_space
*aspace
;
941 /* follow-fork child, detach-on-fork on. */
943 vfork_parent
->pending_detach
= 0;
945 scoped_restore_current_pspace_and_thread restore_thread
;
947 /* We're letting loose of the parent. */
948 thread_info
*tp
= any_live_thread_of_inferior (vfork_parent
);
949 switch_to_thread (tp
);
951 /* We're about to detach from the parent, which implicitly
952 removes breakpoints from its address space. There's a
953 catch here: we want to reuse the spaces for the child,
954 but, parent/child are still sharing the pspace at this
955 point, although the exec in reality makes the kernel give
956 the child a fresh set of new pages. The problem here is
957 that the breakpoints module being unaware of this, would
958 likely chose the child process to write to the parent
959 address space. Swapping the child temporarily away from
960 the spaces has the desired effect. Yes, this is "sort
963 pspace
= inf
->pspace
;
964 aspace
= inf
->aspace
;
968 if (print_inferior_events
)
971 = target_pid_to_str (ptid_t (vfork_parent
->pid
));
973 target_terminal::ours_for_output ();
977 fprintf_filtered (gdb_stdlog
,
978 _("[Detaching vfork parent %s "
979 "after child exec]\n"), pidstr
.c_str ());
983 fprintf_filtered (gdb_stdlog
,
984 _("[Detaching vfork parent %s "
985 "after child exit]\n"), pidstr
.c_str ());
989 target_detach (vfork_parent
, 0);
992 inf
->pspace
= pspace
;
993 inf
->aspace
= aspace
;
997 /* We're staying attached to the parent, so, really give the
998 child a new address space. */
999 inf
->pspace
= new program_space (maybe_new_address_space ());
1000 inf
->aspace
= inf
->pspace
->aspace
;
1002 set_current_program_space (inf
->pspace
);
1004 resume_parent
= vfork_parent
->pid
;
1008 /* If this is a vfork child exiting, then the pspace and
1009 aspaces were shared with the parent. Since we're
1010 reporting the process exit, we'll be mourning all that is
1011 found in the address space, and switching to null_ptid,
1012 preparing to start a new inferior. But, since we don't
1013 want to clobber the parent's address/program spaces, we
1014 go ahead and create a new one for this exiting
1017 /* Switch to no-thread while running clone_program_space, so
1018 that clone_program_space doesn't want to read the
1019 selected frame of a dead process. */
1020 scoped_restore_current_thread restore_thread
;
1021 switch_to_no_thread ();
1023 inf
->pspace
= new program_space (maybe_new_address_space ());
1024 inf
->aspace
= inf
->pspace
->aspace
;
1025 set_current_program_space (inf
->pspace
);
1027 inf
->symfile_flags
= SYMFILE_NO_READ
;
1028 clone_program_space (inf
->pspace
, vfork_parent
->pspace
);
1030 resume_parent
= vfork_parent
->pid
;
1033 gdb_assert (current_program_space
== inf
->pspace
);
1035 if (non_stop
&& resume_parent
!= -1)
1037 /* If the user wanted the parent to be running, let it go
1039 scoped_restore_current_thread restore_thread
;
1041 infrun_debug_printf ("resuming vfork parent process %d",
1044 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
1049 /* Enum strings for "set|show follow-exec-mode". */
1051 static const char follow_exec_mode_new
[] = "new";
1052 static const char follow_exec_mode_same
[] = "same";
1053 static const char *const follow_exec_mode_names
[] =
1055 follow_exec_mode_new
,
1056 follow_exec_mode_same
,
1060 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1062 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1063 struct cmd_list_element
*c
, const char *value
)
1065 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1068 /* EXEC_FILE_TARGET is assumed to be non-NULL. */
1071 follow_exec (ptid_t ptid
, const char *exec_file_target
)
1073 int pid
= ptid
.pid ();
1074 ptid_t process_ptid
;
1076 /* Switch terminal for any messages produced e.g. by
1077 breakpoint_re_set. */
1078 target_terminal::ours_for_output ();
1080 /* This is an exec event that we actually wish to pay attention to.
1081 Refresh our symbol table to the newly exec'd program, remove any
1082 momentary bp's, etc.
1084 If there are breakpoints, they aren't really inserted now,
1085 since the exec() transformed our inferior into a fresh set
1088 We want to preserve symbolic breakpoints on the list, since
1089 we have hopes that they can be reset after the new a.out's
1090 symbol table is read.
1092 However, any "raw" breakpoints must be removed from the list
1093 (e.g., the solib bp's), since their address is probably invalid
1096 And, we DON'T want to call delete_breakpoints() here, since
1097 that may write the bp's "shadow contents" (the instruction
1098 value that was overwritten with a TRAP instruction). Since
1099 we now have a new a.out, those shadow contents aren't valid. */
1101 mark_breakpoints_out ();
1103 /* The target reports the exec event to the main thread, even if
1104 some other thread does the exec, and even if the main thread was
1105 stopped or already gone. We may still have non-leader threads of
1106 the process on our list. E.g., on targets that don't have thread
1107 exit events (like remote); or on native Linux in non-stop mode if
1108 there were only two threads in the inferior and the non-leader
1109 one is the one that execs (and nothing forces an update of the
1110 thread list up to here). When debugging remotely, it's best to
1111 avoid extra traffic, when possible, so avoid syncing the thread
1112 list with the target, and instead go ahead and delete all threads
1113 of the process but one that reported the event. Note this must
1114 be done before calling update_breakpoints_after_exec, as
1115 otherwise clearing the threads' resources would reference stale
1116 thread breakpoints -- it may have been one of these threads that
1117 stepped across the exec. We could just clear their stepping
1118 states, but as long as we're iterating, might as well delete
1119 them. Deleting them now rather than at the next user-visible
1120 stop provides a nicer sequence of events for user and MI
1122 for (thread_info
*th
: all_threads_safe ())
1123 if (th
->ptid
.pid () == pid
&& th
->ptid
!= ptid
)
1126 /* We also need to clear any left over stale state for the
1127 leader/event thread. E.g., if there was any step-resume
1128 breakpoint or similar, it's gone now. We cannot truly
1129 step-to-next statement through an exec(). */
1130 thread_info
*th
= inferior_thread ();
1131 th
->control
.step_resume_breakpoint
= NULL
;
1132 th
->control
.exception_resume_breakpoint
= NULL
;
1133 th
->control
.single_step_breakpoints
= NULL
;
1134 th
->control
.step_range_start
= 0;
1135 th
->control
.step_range_end
= 0;
1137 /* The user may have had the main thread held stopped in the
1138 previous image (e.g., schedlock on, or non-stop). Release
1140 th
->stop_requested
= 0;
1142 update_breakpoints_after_exec ();
1144 /* What is this a.out's name? */
1145 process_ptid
= ptid_t (pid
);
1146 printf_unfiltered (_("%s is executing new program: %s\n"),
1147 target_pid_to_str (process_ptid
).c_str (),
1150 /* We've followed the inferior through an exec. Therefore, the
1151 inferior has essentially been killed & reborn. */
1153 breakpoint_init_inferior (inf_execd
);
1155 gdb::unique_xmalloc_ptr
<char> exec_file_host
1156 = exec_file_find (exec_file_target
, NULL
);
1158 /* If we were unable to map the executable target pathname onto a host
1159 pathname, tell the user that. Otherwise GDB's subsequent behavior
1160 is confusing. Maybe it would even be better to stop at this point
1161 so that the user can specify a file manually before continuing. */
1162 if (exec_file_host
== NULL
)
1163 warning (_("Could not load symbols for executable %s.\n"
1164 "Do you need \"set sysroot\"?"),
1167 /* Reset the shared library package. This ensures that we get a
1168 shlib event when the child reaches "_start", at which point the
1169 dld will have had a chance to initialize the child. */
1170 /* Also, loading a symbol file below may trigger symbol lookups, and
1171 we don't want those to be satisfied by the libraries of the
1172 previous incarnation of this process. */
1173 no_shared_libraries (NULL
, 0);
1175 struct inferior
*inf
= current_inferior ();
1177 if (follow_exec_mode_string
== follow_exec_mode_new
)
1179 /* The user wants to keep the old inferior and program spaces
1180 around. Create a new fresh one, and switch to it. */
1182 /* Do exit processing for the original inferior before setting the new
1183 inferior's pid. Having two inferiors with the same pid would confuse
1184 find_inferior_p(t)id. Transfer the terminal state and info from the
1185 old to the new inferior. */
1186 inferior
*new_inferior
= add_inferior_with_spaces ();
1188 swap_terminal_info (new_inferior
, inf
);
1189 exit_inferior_silent (inf
);
1191 new_inferior
->pid
= pid
;
1192 target_follow_exec (new_inferior
, ptid
, exec_file_target
);
1194 /* We continue with the new inferior. */
1199 /* The old description may no longer be fit for the new image.
1200 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1201 old description; we'll read a new one below. No need to do
1202 this on "follow-exec-mode new", as the old inferior stays
1203 around (its description is later cleared/refetched on
1205 target_clear_description ();
1206 target_follow_exec (inf
, ptid
, exec_file_target
);
1209 gdb_assert (current_inferior () == inf
);
1210 gdb_assert (current_program_space
== inf
->pspace
);
1212 /* Attempt to open the exec file. SYMFILE_DEFER_BP_RESET is used
1213 because the proper displacement for a PIE (Position Independent
1214 Executable) main symbol file will only be computed by
1215 solib_create_inferior_hook below. breakpoint_re_set would fail
1216 to insert the breakpoints with the zero displacement. */
1217 try_open_exec_file (exec_file_host
.get (), inf
, SYMFILE_DEFER_BP_RESET
);
1219 /* If the target can specify a description, read it. Must do this
1220 after flipping to the new executable (because the target supplied
1221 description must be compatible with the executable's
1222 architecture, and the old executable may e.g., be 32-bit, while
1223 the new one 64-bit), and before anything involving memory or
1225 target_find_description ();
1227 gdb::observers::inferior_execd
.notify (inf
);
1229 breakpoint_re_set ();
1231 /* Reinsert all breakpoints. (Those which were symbolic have
1232 been reset to the proper address in the new a.out, thanks
1233 to symbol_file_command...). */
1234 insert_breakpoints ();
1236 /* The next resume of this inferior should bring it to the shlib
1237 startup breakpoints. (If the user had also set bp's on
1238 "main" from the old (parent) process, then they'll auto-
1239 matically get reset there in the new process.). */
1242 /* The chain of threads that need to do a step-over operation to get
1243 past e.g., a breakpoint. What technique is used to step over the
1244 breakpoint/watchpoint does not matter -- all threads end up in the
1245 same queue, to maintain rough temporal order of execution, in order
1246 to avoid starvation, otherwise, we could e.g., find ourselves
1247 constantly stepping the same couple threads past their breakpoints
1248 over and over, if the single-step finish fast enough. */
1249 struct thread_info
*global_thread_step_over_chain_head
;
1251 /* Bit flags indicating what the thread needs to step over. */
1253 enum step_over_what_flag
1255 /* Step over a breakpoint. */
1256 STEP_OVER_BREAKPOINT
= 1,
1258 /* Step past a non-continuable watchpoint, in order to let the
1259 instruction execute so we can evaluate the watchpoint
1261 STEP_OVER_WATCHPOINT
= 2
1263 DEF_ENUM_FLAGS_TYPE (enum step_over_what_flag
, step_over_what
);
1265 /* Info about an instruction that is being stepped over. */
1267 struct step_over_info
1269 /* If we're stepping past a breakpoint, this is the address space
1270 and address of the instruction the breakpoint is set at. We'll
1271 skip inserting all breakpoints here. Valid iff ASPACE is
1273 const address_space
*aspace
= nullptr;
1274 CORE_ADDR address
= 0;
1276 /* The instruction being stepped over triggers a nonsteppable
1277 watchpoint. If true, we'll skip inserting watchpoints. */
1278 int nonsteppable_watchpoint_p
= 0;
1280 /* The thread's global number. */
1284 /* The step-over info of the location that is being stepped over.
1286 Note that with async/breakpoint always-inserted mode, a user might
1287 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1288 being stepped over. As setting a new breakpoint inserts all
1289 breakpoints, we need to make sure the breakpoint being stepped over
1290 isn't inserted then. We do that by only clearing the step-over
1291 info when the step-over is actually finished (or aborted).
1293 Presently GDB can only step over one breakpoint at any given time.
1294 Given threads that can't run code in the same address space as the
1295 breakpoint's can't really miss the breakpoint, GDB could be taught
1296 to step-over at most one breakpoint per address space (so this info
1297 could move to the address space object if/when GDB is extended).
1298 The set of breakpoints being stepped over will normally be much
1299 smaller than the set of all breakpoints, so a flag in the
1300 breakpoint location structure would be wasteful. A separate list
1301 also saves complexity and run-time, as otherwise we'd have to go
1302 through all breakpoint locations clearing their flag whenever we
1303 start a new sequence. Similar considerations weigh against storing
1304 this info in the thread object. Plus, not all step overs actually
1305 have breakpoint locations -- e.g., stepping past a single-step
1306 breakpoint, or stepping to complete a non-continuable
1308 static struct step_over_info step_over_info
;
1310 /* Record the address of the breakpoint/instruction we're currently
1312 N.B. We record the aspace and address now, instead of say just the thread,
1313 because when we need the info later the thread may be running. */
1316 set_step_over_info (const address_space
*aspace
, CORE_ADDR address
,
1317 int nonsteppable_watchpoint_p
,
1320 step_over_info
.aspace
= aspace
;
1321 step_over_info
.address
= address
;
1322 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1323 step_over_info
.thread
= thread
;
1326 /* Called when we're not longer stepping over a breakpoint / an
1327 instruction, so all breakpoints are free to be (re)inserted. */
1330 clear_step_over_info (void)
1332 infrun_debug_printf ("clearing step over info");
1333 step_over_info
.aspace
= NULL
;
1334 step_over_info
.address
= 0;
1335 step_over_info
.nonsteppable_watchpoint_p
= 0;
1336 step_over_info
.thread
= -1;
1342 stepping_past_instruction_at (struct address_space
*aspace
,
1345 return (step_over_info
.aspace
!= NULL
1346 && breakpoint_address_match (aspace
, address
,
1347 step_over_info
.aspace
,
1348 step_over_info
.address
));
1354 thread_is_stepping_over_breakpoint (int thread
)
1356 return (step_over_info
.thread
!= -1
1357 && thread
== step_over_info
.thread
);
1363 stepping_past_nonsteppable_watchpoint (void)
1365 return step_over_info
.nonsteppable_watchpoint_p
;
1368 /* Returns true if step-over info is valid. */
1371 step_over_info_valid_p (void)
1373 return (step_over_info
.aspace
!= NULL
1374 || stepping_past_nonsteppable_watchpoint ());
1378 /* Displaced stepping. */
1380 /* In non-stop debugging mode, we must take special care to manage
1381 breakpoints properly; in particular, the traditional strategy for
1382 stepping a thread past a breakpoint it has hit is unsuitable.
1383 'Displaced stepping' is a tactic for stepping one thread past a
1384 breakpoint it has hit while ensuring that other threads running
1385 concurrently will hit the breakpoint as they should.
1387 The traditional way to step a thread T off a breakpoint in a
1388 multi-threaded program in all-stop mode is as follows:
1390 a0) Initially, all threads are stopped, and breakpoints are not
1392 a1) We single-step T, leaving breakpoints uninserted.
1393 a2) We insert breakpoints, and resume all threads.
1395 In non-stop debugging, however, this strategy is unsuitable: we
1396 don't want to have to stop all threads in the system in order to
1397 continue or step T past a breakpoint. Instead, we use displaced
1400 n0) Initially, T is stopped, other threads are running, and
1401 breakpoints are inserted.
1402 n1) We copy the instruction "under" the breakpoint to a separate
1403 location, outside the main code stream, making any adjustments
1404 to the instruction, register, and memory state as directed by
1406 n2) We single-step T over the instruction at its new location.
1407 n3) We adjust the resulting register and memory state as directed
1408 by T's architecture. This includes resetting T's PC to point
1409 back into the main instruction stream.
1412 This approach depends on the following gdbarch methods:
1414 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1415 indicate where to copy the instruction, and how much space must
1416 be reserved there. We use these in step n1.
1418 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1419 address, and makes any necessary adjustments to the instruction,
1420 register contents, and memory. We use this in step n1.
1422 - gdbarch_displaced_step_fixup adjusts registers and memory after
1423 we have successfully single-stepped the instruction, to yield the
1424 same effect the instruction would have had if we had executed it
1425 at its original address. We use this in step n3.
1427 The gdbarch_displaced_step_copy_insn and
1428 gdbarch_displaced_step_fixup functions must be written so that
1429 copying an instruction with gdbarch_displaced_step_copy_insn,
1430 single-stepping across the copied instruction, and then applying
1431 gdbarch_displaced_insn_fixup should have the same effects on the
1432 thread's memory and registers as stepping the instruction in place
1433 would have. Exactly which responsibilities fall to the copy and
1434 which fall to the fixup is up to the author of those functions.
1436 See the comments in gdbarch.sh for details.
1438 Note that displaced stepping and software single-step cannot
1439 currently be used in combination, although with some care I think
1440 they could be made to. Software single-step works by placing
1441 breakpoints on all possible subsequent instructions; if the
1442 displaced instruction is a PC-relative jump, those breakpoints
1443 could fall in very strange places --- on pages that aren't
1444 executable, or at addresses that are not proper instruction
1445 boundaries. (We do generally let other threads run while we wait
1446 to hit the software single-step breakpoint, and they might
1447 encounter such a corrupted instruction.) One way to work around
1448 this would be to have gdbarch_displaced_step_copy_insn fully
1449 simulate the effect of PC-relative instructions (and return NULL)
1450 on architectures that use software single-stepping.
1452 In non-stop mode, we can have independent and simultaneous step
1453 requests, so more than one thread may need to simultaneously step
1454 over a breakpoint. The current implementation assumes there is
1455 only one scratch space per process. In this case, we have to
1456 serialize access to the scratch space. If thread A wants to step
1457 over a breakpoint, but we are currently waiting for some other
1458 thread to complete a displaced step, we leave thread A stopped and
1459 place it in the displaced_step_request_queue. Whenever a displaced
1460 step finishes, we pick the next thread in the queue and start a new
1461 displaced step operation on it. See displaced_step_prepare and
1462 displaced_step_finish for details. */
1464 /* Return true if THREAD is doing a displaced step. */
1467 displaced_step_in_progress_thread (thread_info
*thread
)
1469 gdb_assert (thread
!= NULL
);
1471 return thread
->displaced_step_state
.in_progress ();
1474 /* Return true if INF has a thread doing a displaced step. */
1477 displaced_step_in_progress (inferior
*inf
)
1479 return inf
->displaced_step_state
.in_progress_count
> 0;
1482 /* Return true if any thread is doing a displaced step. */
1485 displaced_step_in_progress_any_thread ()
1487 for (inferior
*inf
: all_non_exited_inferiors ())
1489 if (displaced_step_in_progress (inf
))
1497 infrun_inferior_exit (struct inferior
*inf
)
1499 inf
->displaced_step_state
.reset ();
1500 inf
->thread_waiting_for_vfork_done
= nullptr;
1504 infrun_inferior_execd (inferior
*inf
)
1506 /* If some threads where was doing a displaced step in this inferior at the
1507 moment of the exec, they no longer exist. Even if the exec'ing thread
1508 doing a displaced step, we don't want to to any fixup nor restore displaced
1509 stepping buffer bytes. */
1510 inf
->displaced_step_state
.reset ();
1512 for (thread_info
*thread
: inf
->threads ())
1513 thread
->displaced_step_state
.reset ();
1515 /* Since an in-line step is done with everything else stopped, if there was
1516 one in progress at the time of the exec, it must have been the exec'ing
1518 clear_step_over_info ();
1520 inf
->thread_waiting_for_vfork_done
= nullptr;
1523 /* If ON, and the architecture supports it, GDB will use displaced
1524 stepping to step over breakpoints. If OFF, or if the architecture
1525 doesn't support it, GDB will instead use the traditional
1526 hold-and-step approach. If AUTO (which is the default), GDB will
1527 decide which technique to use to step over breakpoints depending on
1528 whether the target works in a non-stop way (see use_displaced_stepping). */
1530 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1533 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1534 struct cmd_list_element
*c
,
1537 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1538 fprintf_filtered (file
,
1539 _("Debugger's willingness to use displaced stepping "
1540 "to step over breakpoints is %s (currently %s).\n"),
1541 value
, target_is_non_stop_p () ? "on" : "off");
1543 fprintf_filtered (file
,
1544 _("Debugger's willingness to use displaced stepping "
1545 "to step over breakpoints is %s.\n"), value
);
1548 /* Return true if the gdbarch implements the required methods to use
1549 displaced stepping. */
1552 gdbarch_supports_displaced_stepping (gdbarch
*arch
)
1554 /* Only check for the presence of `prepare`. The gdbarch verification ensures
1555 that if `prepare` is provided, so is `finish`. */
1556 return gdbarch_displaced_step_prepare_p (arch
);
1559 /* Return non-zero if displaced stepping can/should be used to step
1560 over breakpoints of thread TP. */
1563 use_displaced_stepping (thread_info
*tp
)
1565 /* If the user disabled it explicitly, don't use displaced stepping. */
1566 if (can_use_displaced_stepping
== AUTO_BOOLEAN_FALSE
)
1569 /* If "auto", only use displaced stepping if the target operates in a non-stop
1571 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
1572 && !target_is_non_stop_p ())
1575 gdbarch
*gdbarch
= get_thread_regcache (tp
)->arch ();
1577 /* If the architecture doesn't implement displaced stepping, don't use
1579 if (!gdbarch_supports_displaced_stepping (gdbarch
))
1582 /* If recording, don't use displaced stepping. */
1583 if (find_record_target () != nullptr)
1586 /* If displaced stepping failed before for this inferior, don't bother trying
1588 if (tp
->inf
->displaced_step_state
.failed_before
)
1594 /* Simple function wrapper around displaced_step_thread_state::reset. */
1597 displaced_step_reset (displaced_step_thread_state
*displaced
)
1599 displaced
->reset ();
1602 /* A cleanup that wraps displaced_step_reset. We use this instead of, say,
1603 SCOPE_EXIT, because it needs to be discardable with "cleanup.release ()". */
1605 using displaced_step_reset_cleanup
= FORWARD_SCOPE_EXIT (displaced_step_reset
);
1610 displaced_step_dump_bytes (const gdb_byte
*buf
, size_t len
)
1614 for (size_t i
= 0; i
< len
; i
++)
1617 ret
+= string_printf ("%02x", buf
[i
]);
1619 ret
+= string_printf (" %02x", buf
[i
]);
1625 /* Prepare to single-step, using displaced stepping.
1627 Note that we cannot use displaced stepping when we have a signal to
1628 deliver. If we have a signal to deliver and an instruction to step
1629 over, then after the step, there will be no indication from the
1630 target whether the thread entered a signal handler or ignored the
1631 signal and stepped over the instruction successfully --- both cases
1632 result in a simple SIGTRAP. In the first case we mustn't do a
1633 fixup, and in the second case we must --- but we can't tell which.
1634 Comments in the code for 'random signals' in handle_inferior_event
1635 explain how we handle this case instead.
1637 Returns DISPLACED_STEP_PREPARE_STATUS_OK if preparing was successful -- this
1638 thread is going to be stepped now; DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE
1639 if displaced stepping this thread got queued; or
1640 DISPLACED_STEP_PREPARE_STATUS_CANT if this instruction can't be displaced
1643 static displaced_step_prepare_status
1644 displaced_step_prepare_throw (thread_info
*tp
)
1646 regcache
*regcache
= get_thread_regcache (tp
);
1647 struct gdbarch
*gdbarch
= regcache
->arch ();
1648 displaced_step_thread_state
&disp_step_thread_state
1649 = tp
->displaced_step_state
;
1651 /* We should never reach this function if the architecture does not
1652 support displaced stepping. */
1653 gdb_assert (gdbarch_supports_displaced_stepping (gdbarch
));
1655 /* Nor if the thread isn't meant to step over a breakpoint. */
1656 gdb_assert (tp
->control
.trap_expected
);
1658 /* Disable range stepping while executing in the scratch pad. We
1659 want a single-step even if executing the displaced instruction in
1660 the scratch buffer lands within the stepping range (e.g., a
1662 tp
->control
.may_range_step
= 0;
1664 /* We are about to start a displaced step for this thread. If one is already
1665 in progress, something's wrong. */
1666 gdb_assert (!disp_step_thread_state
.in_progress ());
1668 if (tp
->inf
->displaced_step_state
.unavailable
)
1670 /* The gdbarch tells us it's not worth asking to try a prepare because
1671 it is likely that it will return unavailable, so don't bother asking. */
1673 displaced_debug_printf ("deferring step of %s",
1674 target_pid_to_str (tp
->ptid
).c_str ());
1676 global_thread_step_over_chain_enqueue (tp
);
1677 return DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE
;
1680 displaced_debug_printf ("displaced-stepping %s now",
1681 target_pid_to_str (tp
->ptid
).c_str ());
1683 scoped_restore_current_thread restore_thread
;
1685 switch_to_thread (tp
);
1687 CORE_ADDR original_pc
= regcache_read_pc (regcache
);
1688 CORE_ADDR displaced_pc
;
1690 displaced_step_prepare_status status
1691 = gdbarch_displaced_step_prepare (gdbarch
, tp
, displaced_pc
);
1693 if (status
== DISPLACED_STEP_PREPARE_STATUS_CANT
)
1695 displaced_debug_printf ("failed to prepare (%s)",
1696 target_pid_to_str (tp
->ptid
).c_str ());
1698 return DISPLACED_STEP_PREPARE_STATUS_CANT
;
1700 else if (status
== DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE
)
1702 /* Not enough displaced stepping resources available, defer this
1703 request by placing it the queue. */
1705 displaced_debug_printf ("not enough resources available, "
1706 "deferring step of %s",
1707 target_pid_to_str (tp
->ptid
).c_str ());
1709 global_thread_step_over_chain_enqueue (tp
);
1711 return DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE
;
1714 gdb_assert (status
== DISPLACED_STEP_PREPARE_STATUS_OK
);
1716 /* Save the information we need to fix things up if the step
1718 disp_step_thread_state
.set (gdbarch
);
1720 tp
->inf
->displaced_step_state
.in_progress_count
++;
1722 displaced_debug_printf ("prepared successfully thread=%s, "
1723 "original_pc=%s, displaced_pc=%s",
1724 target_pid_to_str (tp
->ptid
).c_str (),
1725 paddress (gdbarch
, original_pc
),
1726 paddress (gdbarch
, displaced_pc
));
1728 return DISPLACED_STEP_PREPARE_STATUS_OK
;
1731 /* Wrapper for displaced_step_prepare_throw that disabled further
1732 attempts at displaced stepping if we get a memory error. */
1734 static displaced_step_prepare_status
1735 displaced_step_prepare (thread_info
*thread
)
1737 displaced_step_prepare_status status
1738 = DISPLACED_STEP_PREPARE_STATUS_CANT
;
1742 status
= displaced_step_prepare_throw (thread
);
1744 catch (const gdb_exception_error
&ex
)
1746 if (ex
.error
!= MEMORY_ERROR
1747 && ex
.error
!= NOT_SUPPORTED_ERROR
)
1750 infrun_debug_printf ("caught exception, disabling displaced stepping: %s",
1753 /* Be verbose if "set displaced-stepping" is "on", silent if
1755 if (can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1757 warning (_("disabling displaced stepping: %s"),
1761 /* Disable further displaced stepping attempts. */
1762 thread
->inf
->displaced_step_state
.failed_before
= 1;
1768 /* If we displaced stepped an instruction successfully, adjust registers and
1769 memory to yield the same effect the instruction would have had if we had
1770 executed it at its original address, and return
1771 DISPLACED_STEP_FINISH_STATUS_OK. If the instruction didn't complete,
1772 relocate the PC and return DISPLACED_STEP_FINISH_STATUS_NOT_EXECUTED.
1774 If the thread wasn't displaced stepping, return
1775 DISPLACED_STEP_FINISH_STATUS_OK as well. */
1777 static displaced_step_finish_status
1778 displaced_step_finish (thread_info
*event_thread
, enum gdb_signal signal
)
1780 displaced_step_thread_state
*displaced
= &event_thread
->displaced_step_state
;
1782 /* Was this thread performing a displaced step? */
1783 if (!displaced
->in_progress ())
1784 return DISPLACED_STEP_FINISH_STATUS_OK
;
1786 gdb_assert (event_thread
->inf
->displaced_step_state
.in_progress_count
> 0);
1787 event_thread
->inf
->displaced_step_state
.in_progress_count
--;
1789 /* Fixup may need to read memory/registers. Switch to the thread
1790 that we're fixing up. Also, target_stopped_by_watchpoint checks
1791 the current thread, and displaced_step_restore performs ptid-dependent
1792 memory accesses using current_inferior(). */
1793 switch_to_thread (event_thread
);
1795 displaced_step_reset_cleanup
cleanup (displaced
);
1797 /* Do the fixup, and release the resources acquired to do the displaced
1799 return gdbarch_displaced_step_finish (displaced
->get_original_gdbarch (),
1800 event_thread
, signal
);
1803 /* Data to be passed around while handling an event. This data is
1804 discarded between events. */
1805 struct execution_control_state
1807 process_stratum_target
*target
;
1809 /* The thread that got the event, if this was a thread event; NULL
1811 struct thread_info
*event_thread
;
1813 struct target_waitstatus ws
;
1814 int stop_func_filled_in
;
1815 CORE_ADDR stop_func_start
;
1816 CORE_ADDR stop_func_end
;
1817 const char *stop_func_name
;
1820 /* True if the event thread hit the single-step breakpoint of
1821 another thread. Thus the event doesn't cause a stop, the thread
1822 needs to be single-stepped past the single-step breakpoint before
1823 we can switch back to the original stepping thread. */
1824 int hit_singlestep_breakpoint
;
1827 /* Clear ECS and set it to point at TP. */
1830 reset_ecs (struct execution_control_state
*ecs
, struct thread_info
*tp
)
1832 memset (ecs
, 0, sizeof (*ecs
));
1833 ecs
->event_thread
= tp
;
1834 ecs
->ptid
= tp
->ptid
;
1837 static void keep_going_pass_signal (struct execution_control_state
*ecs
);
1838 static void prepare_to_wait (struct execution_control_state
*ecs
);
1839 static bool keep_going_stepped_thread (struct thread_info
*tp
);
1840 static step_over_what
thread_still_needs_step_over (struct thread_info
*tp
);
1842 /* Are there any pending step-over requests? If so, run all we can
1843 now and return true. Otherwise, return false. */
1846 start_step_over (void)
1848 INFRUN_SCOPED_DEBUG_ENTER_EXIT
;
1852 /* Don't start a new step-over if we already have an in-line
1853 step-over operation ongoing. */
1854 if (step_over_info_valid_p ())
1857 /* Steal the global thread step over chain. As we try to initiate displaced
1858 steps, threads will be enqueued in the global chain if no buffers are
1859 available. If we iterated on the global chain directly, we might iterate
1861 thread_info
*threads_to_step
= global_thread_step_over_chain_head
;
1862 global_thread_step_over_chain_head
= NULL
;
1864 infrun_debug_printf ("stealing global queue of threads to step, length = %d",
1865 thread_step_over_chain_length (threads_to_step
));
1867 bool started
= false;
1869 /* On scope exit (whatever the reason, return or exception), if there are
1870 threads left in the THREADS_TO_STEP chain, put back these threads in the
1874 if (threads_to_step
== nullptr)
1875 infrun_debug_printf ("step-over queue now empty");
1878 infrun_debug_printf ("putting back %d threads to step in global queue",
1879 thread_step_over_chain_length (threads_to_step
));
1881 global_thread_step_over_chain_enqueue_chain (threads_to_step
);
1885 for (thread_info
*tp
= threads_to_step
; tp
!= NULL
; tp
= next
)
1887 struct execution_control_state ecss
;
1888 struct execution_control_state
*ecs
= &ecss
;
1889 step_over_what step_what
;
1890 int must_be_in_line
;
1892 gdb_assert (!tp
->stop_requested
);
1894 next
= thread_step_over_chain_next (threads_to_step
, tp
);
1896 if (tp
->inf
->displaced_step_state
.unavailable
)
1898 /* The arch told us to not even try preparing another displaced step
1899 for this inferior. Just leave the thread in THREADS_TO_STEP, it
1900 will get moved to the global chain on scope exit. */
1904 /* Remove thread from the THREADS_TO_STEP chain. If anything goes wrong
1905 while we try to prepare the displaced step, we don't add it back to
1906 the global step over chain. This is to avoid a thread staying in the
1907 step over chain indefinitely if something goes wrong when resuming it
1908 If the error is intermittent and it still needs a step over, it will
1909 get enqueued again when we try to resume it normally. */
1910 thread_step_over_chain_remove (&threads_to_step
, tp
);
1912 step_what
= thread_still_needs_step_over (tp
);
1913 must_be_in_line
= ((step_what
& STEP_OVER_WATCHPOINT
)
1914 || ((step_what
& STEP_OVER_BREAKPOINT
)
1915 && !use_displaced_stepping (tp
)));
1917 /* We currently stop all threads of all processes to step-over
1918 in-line. If we need to start a new in-line step-over, let
1919 any pending displaced steps finish first. */
1920 if (must_be_in_line
&& displaced_step_in_progress_any_thread ())
1922 global_thread_step_over_chain_enqueue (tp
);
1926 if (tp
->control
.trap_expected
1930 internal_error (__FILE__
, __LINE__
,
1931 "[%s] has inconsistent state: "
1932 "trap_expected=%d, resumed=%d, executing=%d\n",
1933 target_pid_to_str (tp
->ptid
).c_str (),
1934 tp
->control
.trap_expected
,
1939 infrun_debug_printf ("resuming [%s] for step-over",
1940 target_pid_to_str (tp
->ptid
).c_str ());
1942 /* keep_going_pass_signal skips the step-over if the breakpoint
1943 is no longer inserted. In all-stop, we want to keep looking
1944 for a thread that needs a step-over instead of resuming TP,
1945 because we wouldn't be able to resume anything else until the
1946 target stops again. In non-stop, the resume always resumes
1947 only TP, so it's OK to let the thread resume freely. */
1948 if (!target_is_non_stop_p () && !step_what
)
1951 switch_to_thread (tp
);
1952 reset_ecs (ecs
, tp
);
1953 keep_going_pass_signal (ecs
);
1955 if (!ecs
->wait_some_more
)
1956 error (_("Command aborted."));
1958 /* If the thread's step over could not be initiated because no buffers
1959 were available, it was re-added to the global step over chain. */
1962 infrun_debug_printf ("[%s] was resumed.",
1963 target_pid_to_str (tp
->ptid
).c_str ());
1964 gdb_assert (!thread_is_in_step_over_chain (tp
));
1968 infrun_debug_printf ("[%s] was NOT resumed.",
1969 target_pid_to_str (tp
->ptid
).c_str ());
1970 gdb_assert (thread_is_in_step_over_chain (tp
));
1973 /* If we started a new in-line step-over, we're done. */
1974 if (step_over_info_valid_p ())
1976 gdb_assert (tp
->control
.trap_expected
);
1981 if (!target_is_non_stop_p ())
1983 /* On all-stop, shouldn't have resumed unless we needed a
1985 gdb_assert (tp
->control
.trap_expected
1986 || tp
->step_after_step_resume_breakpoint
);
1988 /* With remote targets (at least), in all-stop, we can't
1989 issue any further remote commands until the program stops
1995 /* Either the thread no longer needed a step-over, or a new
1996 displaced stepping sequence started. Even in the latter
1997 case, continue looking. Maybe we can also start another
1998 displaced step on a thread of other process. */
2004 /* Update global variables holding ptids to hold NEW_PTID if they were
2005 holding OLD_PTID. */
2007 infrun_thread_ptid_changed (process_stratum_target
*target
,
2008 ptid_t old_ptid
, ptid_t new_ptid
)
2010 if (inferior_ptid
== old_ptid
2011 && current_inferior ()->process_target () == target
)
2012 inferior_ptid
= new_ptid
;
2017 static const char schedlock_off
[] = "off";
2018 static const char schedlock_on
[] = "on";
2019 static const char schedlock_step
[] = "step";
2020 static const char schedlock_replay
[] = "replay";
2021 static const char *const scheduler_enums
[] = {
2028 static const char *scheduler_mode
= schedlock_replay
;
2030 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
2031 struct cmd_list_element
*c
, const char *value
)
2033 fprintf_filtered (file
,
2034 _("Mode for locking scheduler "
2035 "during execution is \"%s\".\n"),
2040 set_schedlock_func (const char *args
, int from_tty
, struct cmd_list_element
*c
)
2042 if (!target_can_lock_scheduler ())
2044 scheduler_mode
= schedlock_off
;
2045 error (_("Target '%s' cannot support this command."),
2046 target_shortname ());
2050 /* True if execution commands resume all threads of all processes by
2051 default; otherwise, resume only threads of the current inferior
2053 bool sched_multi
= false;
2055 /* Try to setup for software single stepping over the specified location.
2056 Return true if target_resume() should use hardware single step.
2058 GDBARCH the current gdbarch.
2059 PC the location to step over. */
2062 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
2064 bool hw_step
= true;
2066 if (execution_direction
== EXEC_FORWARD
2067 && gdbarch_software_single_step_p (gdbarch
))
2068 hw_step
= !insert_single_step_breakpoints (gdbarch
);
2076 user_visible_resume_ptid (int step
)
2082 /* With non-stop mode on, threads are always handled
2084 resume_ptid
= inferior_ptid
;
2086 else if ((scheduler_mode
== schedlock_on
)
2087 || (scheduler_mode
== schedlock_step
&& step
))
2089 /* User-settable 'scheduler' mode requires solo thread
2091 resume_ptid
= inferior_ptid
;
2093 else if ((scheduler_mode
== schedlock_replay
)
2094 && target_record_will_replay (minus_one_ptid
, execution_direction
))
2096 /* User-settable 'scheduler' mode requires solo thread resume in replay
2098 resume_ptid
= inferior_ptid
;
2100 else if (!sched_multi
&& target_supports_multi_process ())
2102 /* Resume all threads of the current process (and none of other
2104 resume_ptid
= ptid_t (inferior_ptid
.pid ());
2108 /* Resume all threads of all processes. */
2109 resume_ptid
= RESUME_ALL
;
2117 process_stratum_target
*
2118 user_visible_resume_target (ptid_t resume_ptid
)
2120 return (resume_ptid
== minus_one_ptid
&& sched_multi
2122 : current_inferior ()->process_target ());
2125 /* Return a ptid representing the set of threads that we will resume,
2126 in the perspective of the target, assuming run control handling
2127 does not require leaving some threads stopped (e.g., stepping past
2128 breakpoint). USER_STEP indicates whether we're about to start the
2129 target for a stepping command. */
2132 internal_resume_ptid (int user_step
)
2134 /* In non-stop, we always control threads individually. Note that
2135 the target may always work in non-stop mode even with "set
2136 non-stop off", in which case user_visible_resume_ptid could
2137 return a wildcard ptid. */
2138 if (target_is_non_stop_p ())
2139 return inferior_ptid
;
2141 return user_visible_resume_ptid (user_step
);
2144 /* Wrapper for target_resume, that handles infrun-specific
2148 do_target_resume (ptid_t resume_ptid
, bool step
, enum gdb_signal sig
)
2150 struct thread_info
*tp
= inferior_thread ();
2152 gdb_assert (!tp
->stop_requested
);
2154 /* Install inferior's terminal modes. */
2155 target_terminal::inferior ();
2157 /* Avoid confusing the next resume, if the next stop/resume
2158 happens to apply to another thread. */
2159 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2161 /* Advise target which signals may be handled silently.
2163 If we have removed breakpoints because we are stepping over one
2164 in-line (in any thread), we need to receive all signals to avoid
2165 accidentally skipping a breakpoint during execution of a signal
2168 Likewise if we're displaced stepping, otherwise a trap for a
2169 breakpoint in a signal handler might be confused with the
2170 displaced step finishing. We don't make the displaced_step_finish
2171 step distinguish the cases instead, because:
2173 - a backtrace while stopped in the signal handler would show the
2174 scratch pad as frame older than the signal handler, instead of
2175 the real mainline code.
2177 - when the thread is later resumed, the signal handler would
2178 return to the scratch pad area, which would no longer be
2180 if (step_over_info_valid_p ()
2181 || displaced_step_in_progress (tp
->inf
))
2182 target_pass_signals ({});
2184 target_pass_signals (signal_pass
);
2186 target_resume (resume_ptid
, step
, sig
);
2188 if (target_can_async_p ())
2192 /* Resume the inferior. SIG is the signal to give the inferior
2193 (GDB_SIGNAL_0 for none). Note: don't call this directly; instead
2194 call 'resume', which handles exceptions. */
2197 resume_1 (enum gdb_signal sig
)
2199 struct regcache
*regcache
= get_current_regcache ();
2200 struct gdbarch
*gdbarch
= regcache
->arch ();
2201 struct thread_info
*tp
= inferior_thread ();
2202 const address_space
*aspace
= regcache
->aspace ();
2204 /* This represents the user's step vs continue request. When
2205 deciding whether "set scheduler-locking step" applies, it's the
2206 user's intention that counts. */
2207 const int user_step
= tp
->control
.stepping_command
;
2208 /* This represents what we'll actually request the target to do.
2209 This can decay from a step to a continue, if e.g., we need to
2210 implement single-stepping with breakpoints (software
2214 gdb_assert (!tp
->stop_requested
);
2215 gdb_assert (!thread_is_in_step_over_chain (tp
));
2217 if (tp
->suspend
.waitstatus_pending_p
)
2220 ("thread %s has pending wait "
2221 "status %s (currently_stepping=%d).",
2222 target_pid_to_str (tp
->ptid
).c_str (),
2223 target_waitstatus_to_string (&tp
->suspend
.waitstatus
).c_str (),
2224 currently_stepping (tp
));
2226 tp
->inf
->process_target ()->threads_executing
= true;
2229 /* FIXME: What should we do if we are supposed to resume this
2230 thread with a signal? Maybe we should maintain a queue of
2231 pending signals to deliver. */
2232 if (sig
!= GDB_SIGNAL_0
)
2234 warning (_("Couldn't deliver signal %s to %s."),
2235 gdb_signal_to_name (sig
),
2236 target_pid_to_str (tp
->ptid
).c_str ());
2239 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2241 if (target_can_async_p ())
2244 /* Tell the event loop we have an event to process. */
2245 mark_async_event_handler (infrun_async_inferior_event_token
);
2250 tp
->stepped_breakpoint
= 0;
2252 /* Depends on stepped_breakpoint. */
2253 step
= currently_stepping (tp
);
2255 if (current_inferior ()->thread_waiting_for_vfork_done
!= nullptr)
2257 /* Don't try to single-step a vfork parent that is waiting for
2258 the child to get out of the shared memory region (by exec'ing
2259 or exiting). This is particularly important on software
2260 single-step archs, as the child process would trip on the
2261 software single step breakpoint inserted for the parent
2262 process. Since the parent will not actually execute any
2263 instruction until the child is out of the shared region (such
2264 are vfork's semantics), it is safe to simply continue it.
2265 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2266 the parent, and tell it to `keep_going', which automatically
2267 re-sets it stepping. */
2268 infrun_debug_printf ("resume : clear step");
2272 CORE_ADDR pc
= regcache_read_pc (regcache
);
2274 infrun_debug_printf ("step=%d, signal=%s, trap_expected=%d, "
2275 "current thread [%s] at %s",
2276 step
, gdb_signal_to_symbol_string (sig
),
2277 tp
->control
.trap_expected
,
2278 target_pid_to_str (inferior_ptid
).c_str (),
2279 paddress (gdbarch
, pc
));
2281 /* Normally, by the time we reach `resume', the breakpoints are either
2282 removed or inserted, as appropriate. The exception is if we're sitting
2283 at a permanent breakpoint; we need to step over it, but permanent
2284 breakpoints can't be removed. So we have to test for it here. */
2285 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2287 if (sig
!= GDB_SIGNAL_0
)
2289 /* We have a signal to pass to the inferior. The resume
2290 may, or may not take us to the signal handler. If this
2291 is a step, we'll need to stop in the signal handler, if
2292 there's one, (if the target supports stepping into
2293 handlers), or in the next mainline instruction, if
2294 there's no handler. If this is a continue, we need to be
2295 sure to run the handler with all breakpoints inserted.
2296 In all cases, set a breakpoint at the current address
2297 (where the handler returns to), and once that breakpoint
2298 is hit, resume skipping the permanent breakpoint. If
2299 that breakpoint isn't hit, then we've stepped into the
2300 signal handler (or hit some other event). We'll delete
2301 the step-resume breakpoint then. */
2303 infrun_debug_printf ("resume: skipping permanent breakpoint, "
2304 "deliver signal first");
2306 clear_step_over_info ();
2307 tp
->control
.trap_expected
= 0;
2309 if (tp
->control
.step_resume_breakpoint
== NULL
)
2311 /* Set a "high-priority" step-resume, as we don't want
2312 user breakpoints at PC to trigger (again) when this
2314 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2315 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2317 tp
->step_after_step_resume_breakpoint
= step
;
2320 insert_breakpoints ();
2324 /* There's no signal to pass, we can go ahead and skip the
2325 permanent breakpoint manually. */
2326 infrun_debug_printf ("skipping permanent breakpoint");
2327 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2328 /* Update pc to reflect the new address from which we will
2329 execute instructions. */
2330 pc
= regcache_read_pc (regcache
);
2334 /* We've already advanced the PC, so the stepping part
2335 is done. Now we need to arrange for a trap to be
2336 reported to handle_inferior_event. Set a breakpoint
2337 at the current PC, and run to it. Don't update
2338 prev_pc, because if we end in
2339 switch_back_to_stepped_thread, we want the "expected
2340 thread advanced also" branch to be taken. IOW, we
2341 don't want this thread to step further from PC
2343 gdb_assert (!step_over_info_valid_p ());
2344 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2345 insert_breakpoints ();
2347 resume_ptid
= internal_resume_ptid (user_step
);
2348 do_target_resume (resume_ptid
, false, GDB_SIGNAL_0
);
2355 /* If we have a breakpoint to step over, make sure to do a single
2356 step only. Same if we have software watchpoints. */
2357 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2358 tp
->control
.may_range_step
= 0;
2360 /* If displaced stepping is enabled, step over breakpoints by executing a
2361 copy of the instruction at a different address.
2363 We can't use displaced stepping when we have a signal to deliver;
2364 the comments for displaced_step_prepare explain why. The
2365 comments in the handle_inferior event for dealing with 'random
2366 signals' explain what we do instead.
2368 We can't use displaced stepping when we are waiting for vfork_done
2369 event, displaced stepping breaks the vfork child similarly as single
2370 step software breakpoint. */
2371 if (tp
->control
.trap_expected
2372 && use_displaced_stepping (tp
)
2373 && !step_over_info_valid_p ()
2374 && sig
== GDB_SIGNAL_0
2375 && current_inferior ()->thread_waiting_for_vfork_done
== nullptr)
2377 displaced_step_prepare_status prepare_status
2378 = displaced_step_prepare (tp
);
2380 if (prepare_status
== DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE
)
2382 infrun_debug_printf ("Got placed in step-over queue");
2384 tp
->control
.trap_expected
= 0;
2387 else if (prepare_status
== DISPLACED_STEP_PREPARE_STATUS_CANT
)
2389 /* Fallback to stepping over the breakpoint in-line. */
2391 if (target_is_non_stop_p ())
2392 stop_all_threads ("displaced stepping falling back on inline stepping");
2394 set_step_over_info (regcache
->aspace (),
2395 regcache_read_pc (regcache
), 0, tp
->global_num
);
2397 step
= maybe_software_singlestep (gdbarch
, pc
);
2399 insert_breakpoints ();
2401 else if (prepare_status
== DISPLACED_STEP_PREPARE_STATUS_OK
)
2403 /* Update pc to reflect the new address from which we will
2404 execute instructions due to displaced stepping. */
2405 pc
= regcache_read_pc (get_thread_regcache (tp
));
2407 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
);
2410 gdb_assert_not_reached (_("Invalid displaced_step_prepare_status "
2414 /* Do we need to do it the hard way, w/temp breakpoints? */
2416 step
= maybe_software_singlestep (gdbarch
, pc
);
2418 /* Currently, our software single-step implementation leads to different
2419 results than hardware single-stepping in one situation: when stepping
2420 into delivering a signal which has an associated signal handler,
2421 hardware single-step will stop at the first instruction of the handler,
2422 while software single-step will simply skip execution of the handler.
2424 For now, this difference in behavior is accepted since there is no
2425 easy way to actually implement single-stepping into a signal handler
2426 without kernel support.
2428 However, there is one scenario where this difference leads to follow-on
2429 problems: if we're stepping off a breakpoint by removing all breakpoints
2430 and then single-stepping. In this case, the software single-step
2431 behavior means that even if there is a *breakpoint* in the signal
2432 handler, GDB still would not stop.
2434 Fortunately, we can at least fix this particular issue. We detect
2435 here the case where we are about to deliver a signal while software
2436 single-stepping with breakpoints removed. In this situation, we
2437 revert the decisions to remove all breakpoints and insert single-
2438 step breakpoints, and instead we install a step-resume breakpoint
2439 at the current address, deliver the signal without stepping, and
2440 once we arrive back at the step-resume breakpoint, actually step
2441 over the breakpoint we originally wanted to step over. */
2442 if (thread_has_single_step_breakpoints_set (tp
)
2443 && sig
!= GDB_SIGNAL_0
2444 && step_over_info_valid_p ())
2446 /* If we have nested signals or a pending signal is delivered
2447 immediately after a handler returns, might already have
2448 a step-resume breakpoint set on the earlier handler. We cannot
2449 set another step-resume breakpoint; just continue on until the
2450 original breakpoint is hit. */
2451 if (tp
->control
.step_resume_breakpoint
== NULL
)
2453 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2454 tp
->step_after_step_resume_breakpoint
= 1;
2457 delete_single_step_breakpoints (tp
);
2459 clear_step_over_info ();
2460 tp
->control
.trap_expected
= 0;
2462 insert_breakpoints ();
2465 /* If STEP is set, it's a request to use hardware stepping
2466 facilities. But in that case, we should never
2467 use singlestep breakpoint. */
2468 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2470 /* Decide the set of threads to ask the target to resume. */
2471 if (tp
->control
.trap_expected
)
2473 /* We're allowing a thread to run past a breakpoint it has
2474 hit, either by single-stepping the thread with the breakpoint
2475 removed, or by displaced stepping, with the breakpoint inserted.
2476 In the former case, we need to single-step only this thread,
2477 and keep others stopped, as they can miss this breakpoint if
2478 allowed to run. That's not really a problem for displaced
2479 stepping, but, we still keep other threads stopped, in case
2480 another thread is also stopped for a breakpoint waiting for
2481 its turn in the displaced stepping queue. */
2482 resume_ptid
= inferior_ptid
;
2485 resume_ptid
= internal_resume_ptid (user_step
);
2487 if (execution_direction
!= EXEC_REVERSE
2488 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2490 /* There are two cases where we currently need to step a
2491 breakpoint instruction when we have a signal to deliver:
2493 - See handle_signal_stop where we handle random signals that
2494 could take out us out of the stepping range. Normally, in
2495 that case we end up continuing (instead of stepping) over the
2496 signal handler with a breakpoint at PC, but there are cases
2497 where we should _always_ single-step, even if we have a
2498 step-resume breakpoint, like when a software watchpoint is
2499 set. Assuming single-stepping and delivering a signal at the
2500 same time would takes us to the signal handler, then we could
2501 have removed the breakpoint at PC to step over it. However,
2502 some hardware step targets (like e.g., Mac OS) can't step
2503 into signal handlers, and for those, we need to leave the
2504 breakpoint at PC inserted, as otherwise if the handler
2505 recurses and executes PC again, it'll miss the breakpoint.
2506 So we leave the breakpoint inserted anyway, but we need to
2507 record that we tried to step a breakpoint instruction, so
2508 that adjust_pc_after_break doesn't end up confused.
2510 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2511 in one thread after another thread that was stepping had been
2512 momentarily paused for a step-over. When we re-resume the
2513 stepping thread, it may be resumed from that address with a
2514 breakpoint that hasn't trapped yet. Seen with
2515 gdb.threads/non-stop-fair-events.exp, on targets that don't
2516 do displaced stepping. */
2518 infrun_debug_printf ("resume: [%s] stepped breakpoint",
2519 target_pid_to_str (tp
->ptid
).c_str ());
2521 tp
->stepped_breakpoint
= 1;
2523 /* Most targets can step a breakpoint instruction, thus
2524 executing it normally. But if this one cannot, just
2525 continue and we will hit it anyway. */
2526 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2531 && tp
->control
.trap_expected
2532 && use_displaced_stepping (tp
)
2533 && !step_over_info_valid_p ())
2535 struct regcache
*resume_regcache
= get_thread_regcache (tp
);
2536 struct gdbarch
*resume_gdbarch
= resume_regcache
->arch ();
2537 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2540 read_memory (actual_pc
, buf
, sizeof (buf
));
2541 displaced_debug_printf ("run %s: %s",
2542 paddress (resume_gdbarch
, actual_pc
),
2543 displaced_step_dump_bytes
2544 (buf
, sizeof (buf
)).c_str ());
2547 if (tp
->control
.may_range_step
)
2549 /* If we're resuming a thread with the PC out of the step
2550 range, then we're doing some nested/finer run control
2551 operation, like stepping the thread out of the dynamic
2552 linker or the displaced stepping scratch pad. We
2553 shouldn't have allowed a range step then. */
2554 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2557 do_target_resume (resume_ptid
, step
, sig
);
2561 /* Resume the inferior. SIG is the signal to give the inferior
2562 (GDB_SIGNAL_0 for none). This is a wrapper around 'resume_1' that
2563 rolls back state on error. */
2566 resume (gdb_signal sig
)
2572 catch (const gdb_exception
&ex
)
2574 /* If resuming is being aborted for any reason, delete any
2575 single-step breakpoint resume_1 may have created, to avoid
2576 confusing the following resumption, and to avoid leaving
2577 single-step breakpoints perturbing other threads, in case
2578 we're running in non-stop mode. */
2579 if (inferior_ptid
!= null_ptid
)
2580 delete_single_step_breakpoints (inferior_thread ());
2590 /* Counter that tracks number of user visible stops. This can be used
2591 to tell whether a command has proceeded the inferior past the
2592 current location. This allows e.g., inferior function calls in
2593 breakpoint commands to not interrupt the command list. When the
2594 call finishes successfully, the inferior is standing at the same
2595 breakpoint as if nothing happened (and so we don't call
2597 static ULONGEST current_stop_id
;
2604 return current_stop_id
;
2607 /* Called when we report a user visible stop. */
2615 /* Clear out all variables saying what to do when inferior is continued.
2616 First do this, then set the ones you want, then call `proceed'. */
2619 clear_proceed_status_thread (struct thread_info
*tp
)
2621 infrun_debug_printf ("%s", target_pid_to_str (tp
->ptid
).c_str ());
2623 /* If we're starting a new sequence, then the previous finished
2624 single-step is no longer relevant. */
2625 if (tp
->suspend
.waitstatus_pending_p
)
2627 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
2629 infrun_debug_printf ("pending event of %s was a finished step. "
2631 target_pid_to_str (tp
->ptid
).c_str ());
2633 tp
->suspend
.waitstatus_pending_p
= 0;
2634 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2639 ("thread %s has pending wait status %s (currently_stepping=%d).",
2640 target_pid_to_str (tp
->ptid
).c_str (),
2641 target_waitstatus_to_string (&tp
->suspend
.waitstatus
).c_str (),
2642 currently_stepping (tp
));
2646 /* If this signal should not be seen by program, give it zero.
2647 Used for debugging signals. */
2648 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2649 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2651 delete tp
->thread_fsm
;
2652 tp
->thread_fsm
= NULL
;
2654 tp
->control
.trap_expected
= 0;
2655 tp
->control
.step_range_start
= 0;
2656 tp
->control
.step_range_end
= 0;
2657 tp
->control
.may_range_step
= 0;
2658 tp
->control
.step_frame_id
= null_frame_id
;
2659 tp
->control
.step_stack_frame_id
= null_frame_id
;
2660 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2661 tp
->control
.step_start_function
= NULL
;
2662 tp
->stop_requested
= 0;
2664 tp
->control
.stop_step
= 0;
2666 tp
->control
.proceed_to_finish
= 0;
2668 tp
->control
.stepping_command
= 0;
2670 /* Discard any remaining commands or status from previous stop. */
2671 bpstat_clear (&tp
->control
.stop_bpstat
);
2675 clear_proceed_status (int step
)
2677 /* With scheduler-locking replay, stop replaying other threads if we're
2678 not replaying the user-visible resume ptid.
2680 This is a convenience feature to not require the user to explicitly
2681 stop replaying the other threads. We're assuming that the user's
2682 intent is to resume tracing the recorded process. */
2683 if (!non_stop
&& scheduler_mode
== schedlock_replay
2684 && target_record_is_replaying (minus_one_ptid
)
2685 && !target_record_will_replay (user_visible_resume_ptid (step
),
2686 execution_direction
))
2687 target_record_stop_replaying ();
2689 if (!non_stop
&& inferior_ptid
!= null_ptid
)
2691 ptid_t resume_ptid
= user_visible_resume_ptid (step
);
2692 process_stratum_target
*resume_target
2693 = user_visible_resume_target (resume_ptid
);
2695 /* In all-stop mode, delete the per-thread status of all threads
2696 we're about to resume, implicitly and explicitly. */
2697 for (thread_info
*tp
: all_non_exited_threads (resume_target
, resume_ptid
))
2698 clear_proceed_status_thread (tp
);
2701 if (inferior_ptid
!= null_ptid
)
2703 struct inferior
*inferior
;
2707 /* If in non-stop mode, only delete the per-thread status of
2708 the current thread. */
2709 clear_proceed_status_thread (inferior_thread ());
2712 inferior
= current_inferior ();
2713 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2716 gdb::observers::about_to_proceed
.notify ();
2719 /* Returns true if TP is still stopped at a breakpoint that needs
2720 stepping-over in order to make progress. If the breakpoint is gone
2721 meanwhile, we can skip the whole step-over dance. */
2724 thread_still_needs_step_over_bp (struct thread_info
*tp
)
2726 if (tp
->stepping_over_breakpoint
)
2728 struct regcache
*regcache
= get_thread_regcache (tp
);
2730 if (breakpoint_here_p (regcache
->aspace (),
2731 regcache_read_pc (regcache
))
2732 == ordinary_breakpoint_here
)
2735 tp
->stepping_over_breakpoint
= 0;
2741 /* Check whether thread TP still needs to start a step-over in order
2742 to make progress when resumed. Returns an bitwise or of enum
2743 step_over_what bits, indicating what needs to be stepped over. */
2745 static step_over_what
2746 thread_still_needs_step_over (struct thread_info
*tp
)
2748 step_over_what what
= 0;
2750 if (thread_still_needs_step_over_bp (tp
))
2751 what
|= STEP_OVER_BREAKPOINT
;
2753 if (tp
->stepping_over_watchpoint
2754 && !target_have_steppable_watchpoint ())
2755 what
|= STEP_OVER_WATCHPOINT
;
2760 /* Returns true if scheduler locking applies. STEP indicates whether
2761 we're about to do a step/next-like command to a thread. */
2764 schedlock_applies (struct thread_info
*tp
)
2766 return (scheduler_mode
== schedlock_on
2767 || (scheduler_mode
== schedlock_step
2768 && tp
->control
.stepping_command
)
2769 || (scheduler_mode
== schedlock_replay
2770 && target_record_will_replay (minus_one_ptid
,
2771 execution_direction
)));
2774 /* Set process_stratum_target::COMMIT_RESUMED_STATE in all target
2775 stacks that have threads executing and don't have threads with
2779 maybe_set_commit_resumed_all_targets ()
2781 scoped_restore_current_thread restore_thread
;
2783 for (inferior
*inf
: all_non_exited_inferiors ())
2785 process_stratum_target
*proc_target
= inf
->process_target ();
2787 if (proc_target
->commit_resumed_state
)
2789 /* We already set this in a previous iteration, via another
2790 inferior sharing the process_stratum target. */
2794 /* If the target has no resumed threads, it would be useless to
2795 ask it to commit the resumed threads. */
2796 if (!proc_target
->threads_executing
)
2798 infrun_debug_printf ("not requesting commit-resumed for target "
2799 "%s, no resumed threads",
2800 proc_target
->shortname ());
2804 /* As an optimization, if a thread from this target has some
2805 status to report, handle it before requiring the target to
2806 commit its resumed threads: handling the status might lead to
2807 resuming more threads. */
2808 bool has_thread_with_pending_status
= false;
2809 for (thread_info
*thread
: all_non_exited_threads (proc_target
))
2810 if (thread
->resumed
&& thread
->suspend
.waitstatus_pending_p
)
2812 has_thread_with_pending_status
= true;
2816 if (has_thread_with_pending_status
)
2818 infrun_debug_printf ("not requesting commit-resumed for target %s, a"
2819 " thread has a pending waitstatus",
2820 proc_target
->shortname ());
2824 switch_to_inferior_no_thread (inf
);
2826 if (target_has_pending_events ())
2828 infrun_debug_printf ("not requesting commit-resumed for target %s, "
2829 "target has pending events",
2830 proc_target
->shortname ());
2834 infrun_debug_printf ("enabling commit-resumed for target %s",
2835 proc_target
->shortname ());
2837 proc_target
->commit_resumed_state
= true;
2844 maybe_call_commit_resumed_all_targets ()
2846 scoped_restore_current_thread restore_thread
;
2848 for (inferior
*inf
: all_non_exited_inferiors ())
2850 process_stratum_target
*proc_target
= inf
->process_target ();
2852 if (!proc_target
->commit_resumed_state
)
2855 switch_to_inferior_no_thread (inf
);
2857 infrun_debug_printf ("calling commit_resumed for target %s",
2858 proc_target
->shortname());
2860 target_commit_resumed ();
2864 /* To track nesting of scoped_disable_commit_resumed objects, ensuring
2865 that only the outermost one attempts to re-enable
2867 static bool enable_commit_resumed
= true;
2871 scoped_disable_commit_resumed::scoped_disable_commit_resumed
2872 (const char *reason
)
2873 : m_reason (reason
),
2874 m_prev_enable_commit_resumed (enable_commit_resumed
)
2876 infrun_debug_printf ("reason=%s", m_reason
);
2878 enable_commit_resumed
= false;
2880 for (inferior
*inf
: all_non_exited_inferiors ())
2882 process_stratum_target
*proc_target
= inf
->process_target ();
2884 if (m_prev_enable_commit_resumed
)
2886 /* This is the outermost instance: force all
2887 COMMIT_RESUMED_STATE to false. */
2888 proc_target
->commit_resumed_state
= false;
2892 /* This is not the outermost instance, we expect
2893 COMMIT_RESUMED_STATE to have been cleared by the
2894 outermost instance. */
2895 gdb_assert (!proc_target
->commit_resumed_state
);
2903 scoped_disable_commit_resumed::reset ()
2909 infrun_debug_printf ("reason=%s", m_reason
);
2911 gdb_assert (!enable_commit_resumed
);
2913 enable_commit_resumed
= m_prev_enable_commit_resumed
;
2915 if (m_prev_enable_commit_resumed
)
2917 /* This is the outermost instance, re-enable
2918 COMMIT_RESUMED_STATE on the targets where it's possible. */
2919 maybe_set_commit_resumed_all_targets ();
2923 /* This is not the outermost instance, we expect
2924 COMMIT_RESUMED_STATE to still be false. */
2925 for (inferior
*inf
: all_non_exited_inferiors ())
2927 process_stratum_target
*proc_target
= inf
->process_target ();
2928 gdb_assert (!proc_target
->commit_resumed_state
);
2935 scoped_disable_commit_resumed::~scoped_disable_commit_resumed ()
2943 scoped_disable_commit_resumed::reset_and_commit ()
2946 maybe_call_commit_resumed_all_targets ();
2951 scoped_enable_commit_resumed::scoped_enable_commit_resumed
2952 (const char *reason
)
2953 : m_reason (reason
),
2954 m_prev_enable_commit_resumed (enable_commit_resumed
)
2956 infrun_debug_printf ("reason=%s", m_reason
);
2958 if (!enable_commit_resumed
)
2960 enable_commit_resumed
= true;
2962 /* Re-enable COMMIT_RESUMED_STATE on the targets where it's
2964 maybe_set_commit_resumed_all_targets ();
2966 maybe_call_commit_resumed_all_targets ();
2972 scoped_enable_commit_resumed::~scoped_enable_commit_resumed ()
2974 infrun_debug_printf ("reason=%s", m_reason
);
2976 gdb_assert (enable_commit_resumed
);
2978 enable_commit_resumed
= m_prev_enable_commit_resumed
;
2980 if (!enable_commit_resumed
)
2982 /* Force all COMMIT_RESUMED_STATE back to false. */
2983 for (inferior
*inf
: all_non_exited_inferiors ())
2985 process_stratum_target
*proc_target
= inf
->process_target ();
2986 proc_target
->commit_resumed_state
= false;
2991 /* Check that all the targets we're about to resume are in non-stop
2992 mode. Ideally, we'd only care whether all targets support
2993 target-async, but we're not there yet. E.g., stop_all_threads
2994 doesn't know how to handle all-stop targets. Also, the remote
2995 protocol in all-stop mode is synchronous, irrespective of
2996 target-async, which means that things like a breakpoint re-set
2997 triggered by one target would try to read memory from all targets
3001 check_multi_target_resumption (process_stratum_target
*resume_target
)
3003 if (!non_stop
&& resume_target
== nullptr)
3005 scoped_restore_current_thread restore_thread
;
3007 /* This is used to track whether we're resuming more than one
3009 process_stratum_target
*first_connection
= nullptr;
3011 /* The first inferior we see with a target that does not work in
3012 always-non-stop mode. */
3013 inferior
*first_not_non_stop
= nullptr;
3015 for (inferior
*inf
: all_non_exited_inferiors ())
3017 switch_to_inferior_no_thread (inf
);
3019 if (!target_has_execution ())
3022 process_stratum_target
*proc_target
3023 = current_inferior ()->process_target();
3025 if (!target_is_non_stop_p ())
3026 first_not_non_stop
= inf
;
3028 if (first_connection
== nullptr)
3029 first_connection
= proc_target
;
3030 else if (first_connection
!= proc_target
3031 && first_not_non_stop
!= nullptr)
3033 switch_to_inferior_no_thread (first_not_non_stop
);
3035 proc_target
= current_inferior ()->process_target();
3037 error (_("Connection %d (%s) does not support "
3038 "multi-target resumption."),
3039 proc_target
->connection_number
,
3040 make_target_connection_string (proc_target
).c_str ());
3046 /* Basic routine for continuing the program in various fashions.
3048 ADDR is the address to resume at, or -1 for resume where stopped.
3049 SIGGNAL is the signal to give it, or GDB_SIGNAL_0 for none,
3050 or GDB_SIGNAL_DEFAULT for act according to how it stopped.
3052 You should call clear_proceed_status before calling proceed. */
3055 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
)
3057 INFRUN_SCOPED_DEBUG_ENTER_EXIT
;
3059 struct regcache
*regcache
;
3060 struct gdbarch
*gdbarch
;
3062 struct execution_control_state ecss
;
3063 struct execution_control_state
*ecs
= &ecss
;
3066 /* If we're stopped at a fork/vfork, follow the branch set by the
3067 "set follow-fork-mode" command; otherwise, we'll just proceed
3068 resuming the current thread. */
3069 if (!follow_fork ())
3071 /* The target for some reason decided not to resume. */
3073 if (target_can_async_p ())
3074 inferior_event_handler (INF_EXEC_COMPLETE
);
3078 /* We'll update this if & when we switch to a new thread. */
3079 previous_inferior_ptid
= inferior_ptid
;
3081 regcache
= get_current_regcache ();
3082 gdbarch
= regcache
->arch ();
3083 const address_space
*aspace
= regcache
->aspace ();
3085 pc
= regcache_read_pc_protected (regcache
);
3087 thread_info
*cur_thr
= inferior_thread ();
3089 /* Fill in with reasonable starting values. */
3090 init_thread_stepping_state (cur_thr
);
3092 gdb_assert (!thread_is_in_step_over_chain (cur_thr
));
3095 = user_visible_resume_ptid (cur_thr
->control
.stepping_command
);
3096 process_stratum_target
*resume_target
3097 = user_visible_resume_target (resume_ptid
);
3099 check_multi_target_resumption (resume_target
);
3101 if (addr
== (CORE_ADDR
) -1)
3103 if (pc
== cur_thr
->suspend
.stop_pc
3104 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
3105 && execution_direction
!= EXEC_REVERSE
)
3106 /* There is a breakpoint at the address we will resume at,
3107 step one instruction before inserting breakpoints so that
3108 we do not stop right away (and report a second hit at this
3111 Note, we don't do this in reverse, because we won't
3112 actually be executing the breakpoint insn anyway.
3113 We'll be (un-)executing the previous instruction. */
3114 cur_thr
->stepping_over_breakpoint
= 1;
3115 else if (gdbarch_single_step_through_delay_p (gdbarch
)
3116 && gdbarch_single_step_through_delay (gdbarch
,
3117 get_current_frame ()))
3118 /* We stepped onto an instruction that needs to be stepped
3119 again before re-inserting the breakpoint, do so. */
3120 cur_thr
->stepping_over_breakpoint
= 1;
3124 regcache_write_pc (regcache
, addr
);
3127 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
3128 cur_thr
->suspend
.stop_signal
= siggnal
;
3130 /* If an exception is thrown from this point on, make sure to
3131 propagate GDB's knowledge of the executing state to the
3132 frontend/user running state. */
3133 scoped_finish_thread_state
finish_state (resume_target
, resume_ptid
);
3135 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
3136 threads (e.g., we might need to set threads stepping over
3137 breakpoints first), from the user/frontend's point of view, all
3138 threads in RESUME_PTID are now running. Unless we're calling an
3139 inferior function, as in that case we pretend the inferior
3140 doesn't run at all. */
3141 if (!cur_thr
->control
.in_infcall
)
3142 set_running (resume_target
, resume_ptid
, true);
3144 infrun_debug_printf ("addr=%s, signal=%s", paddress (gdbarch
, addr
),
3145 gdb_signal_to_symbol_string (siggnal
));
3147 annotate_starting ();
3149 /* Make sure that output from GDB appears before output from the
3151 gdb_flush (gdb_stdout
);
3153 /* Since we've marked the inferior running, give it the terminal. A
3154 QUIT/Ctrl-C from here on is forwarded to the target (which can
3155 still detect attempts to unblock a stuck connection with repeated
3156 Ctrl-C from within target_pass_ctrlc). */
3157 target_terminal::inferior ();
3159 /* In a multi-threaded task we may select another thread and
3160 then continue or step.
3162 But if a thread that we're resuming had stopped at a breakpoint,
3163 it will immediately cause another breakpoint stop without any
3164 execution (i.e. it will report a breakpoint hit incorrectly). So
3165 we must step over it first.
3167 Look for threads other than the current (TP) that reported a
3168 breakpoint hit and haven't been resumed yet since. */
3170 /* If scheduler locking applies, we can avoid iterating over all
3172 if (!non_stop
&& !schedlock_applies (cur_thr
))
3174 for (thread_info
*tp
: all_non_exited_threads (resume_target
,
3177 switch_to_thread_no_regs (tp
);
3179 /* Ignore the current thread here. It's handled
3184 if (!thread_still_needs_step_over (tp
))
3187 gdb_assert (!thread_is_in_step_over_chain (tp
));
3189 infrun_debug_printf ("need to step-over [%s] first",
3190 target_pid_to_str (tp
->ptid
).c_str ());
3192 global_thread_step_over_chain_enqueue (tp
);
3195 switch_to_thread (cur_thr
);
3198 /* Enqueue the current thread last, so that we move all other
3199 threads over their breakpoints first. */
3200 if (cur_thr
->stepping_over_breakpoint
)
3201 global_thread_step_over_chain_enqueue (cur_thr
);
3203 /* If the thread isn't started, we'll still need to set its prev_pc,
3204 so that switch_back_to_stepped_thread knows the thread hasn't
3205 advanced. Must do this before resuming any thread, as in
3206 all-stop/remote, once we resume we can't send any other packet
3207 until the target stops again. */
3208 cur_thr
->prev_pc
= regcache_read_pc_protected (regcache
);
3211 scoped_disable_commit_resumed
disable_commit_resumed ("proceeding");
3213 started
= start_step_over ();
3215 if (step_over_info_valid_p ())
3217 /* Either this thread started a new in-line step over, or some
3218 other thread was already doing one. In either case, don't
3219 resume anything else until the step-over is finished. */
3221 else if (started
&& !target_is_non_stop_p ())
3223 /* A new displaced stepping sequence was started. In all-stop,
3224 we can't talk to the target anymore until it next stops. */
3226 else if (!non_stop
&& target_is_non_stop_p ())
3228 INFRUN_SCOPED_DEBUG_START_END
3229 ("resuming threads, all-stop-on-top-of-non-stop");
3231 /* In all-stop, but the target is always in non-stop mode.
3232 Start all other threads that are implicitly resumed too. */
3233 for (thread_info
*tp
: all_non_exited_threads (resume_target
,
3236 switch_to_thread_no_regs (tp
);
3238 if (!tp
->inf
->has_execution ())
3240 infrun_debug_printf ("[%s] target has no execution",
3241 target_pid_to_str (tp
->ptid
).c_str ());
3247 infrun_debug_printf ("[%s] resumed",
3248 target_pid_to_str (tp
->ptid
).c_str ());
3249 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
3253 if (thread_is_in_step_over_chain (tp
))
3255 infrun_debug_printf ("[%s] needs step-over",
3256 target_pid_to_str (tp
->ptid
).c_str ());
3260 infrun_debug_printf ("resuming %s",
3261 target_pid_to_str (tp
->ptid
).c_str ());
3263 reset_ecs (ecs
, tp
);
3264 switch_to_thread (tp
);
3265 keep_going_pass_signal (ecs
);
3266 if (!ecs
->wait_some_more
)
3267 error (_("Command aborted."));
3270 else if (!cur_thr
->resumed
&& !thread_is_in_step_over_chain (cur_thr
))
3272 /* The thread wasn't started, and isn't queued, run it now. */
3273 reset_ecs (ecs
, cur_thr
);
3274 switch_to_thread (cur_thr
);
3275 keep_going_pass_signal (ecs
);
3276 if (!ecs
->wait_some_more
)
3277 error (_("Command aborted."));
3280 disable_commit_resumed
.reset_and_commit ();
3283 finish_state
.release ();
3285 /* If we've switched threads above, switch back to the previously
3286 current thread. We don't want the user to see a different
3288 switch_to_thread (cur_thr
);
3290 /* Tell the event loop to wait for it to stop. If the target
3291 supports asynchronous execution, it'll do this from within
3293 if (!target_can_async_p ())
3294 mark_async_event_handler (infrun_async_inferior_event_token
);
3298 /* Start remote-debugging of a machine over a serial link. */
3301 start_remote (int from_tty
)
3303 inferior
*inf
= current_inferior ();
3304 inf
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
3306 /* Always go on waiting for the target, regardless of the mode. */
3307 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3308 indicate to wait_for_inferior that a target should timeout if
3309 nothing is returned (instead of just blocking). Because of this,
3310 targets expecting an immediate response need to, internally, set
3311 things up so that the target_wait() is forced to eventually
3313 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3314 differentiate to its caller what the state of the target is after
3315 the initial open has been performed. Here we're assuming that
3316 the target has stopped. It should be possible to eventually have
3317 target_open() return to the caller an indication that the target
3318 is currently running and GDB state should be set to the same as
3319 for an async run. */
3320 wait_for_inferior (inf
);
3322 /* Now that the inferior has stopped, do any bookkeeping like
3323 loading shared libraries. We want to do this before normal_stop,
3324 so that the displayed frame is up to date. */
3325 post_create_inferior (from_tty
);
3330 /* Initialize static vars when a new inferior begins. */
3333 init_wait_for_inferior (void)
3335 /* These are meaningless until the first time through wait_for_inferior. */
3337 breakpoint_init_inferior (inf_starting
);
3339 clear_proceed_status (0);
3341 nullify_last_target_wait_ptid ();
3343 previous_inferior_ptid
= inferior_ptid
;
3348 static void handle_inferior_event (struct execution_control_state
*ecs
);
3350 static void handle_step_into_function (struct gdbarch
*gdbarch
,
3351 struct execution_control_state
*ecs
);
3352 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
3353 struct execution_control_state
*ecs
);
3354 static void handle_signal_stop (struct execution_control_state
*ecs
);
3355 static void check_exception_resume (struct execution_control_state
*,
3356 struct frame_info
*);
3358 static void end_stepping_range (struct execution_control_state
*ecs
);
3359 static void stop_waiting (struct execution_control_state
*ecs
);
3360 static void keep_going (struct execution_control_state
*ecs
);
3361 static void process_event_stop_test (struct execution_control_state
*ecs
);
3362 static bool switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
3364 /* This function is attached as a "thread_stop_requested" observer.
3365 Cleanup local state that assumed the PTID was to be resumed, and
3366 report the stop to the frontend. */
3369 infrun_thread_stop_requested (ptid_t ptid
)
3371 process_stratum_target
*curr_target
= current_inferior ()->process_target ();
3373 /* PTID was requested to stop. If the thread was already stopped,
3374 but the user/frontend doesn't know about that yet (e.g., the
3375 thread had been temporarily paused for some step-over), set up
3376 for reporting the stop now. */
3377 for (thread_info
*tp
: all_threads (curr_target
, ptid
))
3379 if (tp
->state
!= THREAD_RUNNING
)
3384 /* Remove matching threads from the step-over queue, so
3385 start_step_over doesn't try to resume them
3387 if (thread_is_in_step_over_chain (tp
))
3388 global_thread_step_over_chain_remove (tp
);
3390 /* If the thread is stopped, but the user/frontend doesn't
3391 know about that yet, queue a pending event, as if the
3392 thread had just stopped now. Unless the thread already had
3394 if (!tp
->suspend
.waitstatus_pending_p
)
3396 tp
->suspend
.waitstatus_pending_p
= 1;
3397 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_STOPPED
;
3398 tp
->suspend
.waitstatus
.value
.sig
= GDB_SIGNAL_0
;
3401 /* Clear the inline-frame state, since we're re-processing the
3403 clear_inline_frame_state (tp
);
3405 /* If this thread was paused because some other thread was
3406 doing an inline-step over, let that finish first. Once
3407 that happens, we'll restart all threads and consume pending
3408 stop events then. */
3409 if (step_over_info_valid_p ())
3412 /* Otherwise we can process the (new) pending event now. Set
3413 it so this pending event is considered by
3420 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
3422 if (target_last_proc_target
== tp
->inf
->process_target ()
3423 && target_last_wait_ptid
== tp
->ptid
)
3424 nullify_last_target_wait_ptid ();
3427 /* Delete the step resume, single-step and longjmp/exception resume
3428 breakpoints of TP. */
3431 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
3433 delete_step_resume_breakpoint (tp
);
3434 delete_exception_resume_breakpoint (tp
);
3435 delete_single_step_breakpoints (tp
);
3438 /* If the target still has execution, call FUNC for each thread that
3439 just stopped. In all-stop, that's all the non-exited threads; in
3440 non-stop, that's the current thread, only. */
3442 typedef void (*for_each_just_stopped_thread_callback_func
)
3443 (struct thread_info
*tp
);
3446 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
3448 if (!target_has_execution () || inferior_ptid
== null_ptid
)
3451 if (target_is_non_stop_p ())
3453 /* If in non-stop mode, only the current thread stopped. */
3454 func (inferior_thread ());
3458 /* In all-stop mode, all threads have stopped. */
3459 for (thread_info
*tp
: all_non_exited_threads ())
3464 /* Delete the step resume and longjmp/exception resume breakpoints of
3465 the threads that just stopped. */
3468 delete_just_stopped_threads_infrun_breakpoints (void)
3470 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3473 /* Delete the single-step breakpoints of the threads that just
3477 delete_just_stopped_threads_single_step_breakpoints (void)
3479 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3485 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3486 const struct target_waitstatus
*ws
)
3488 infrun_debug_printf ("target_wait (%d.%ld.%ld [%s], status) =",
3492 target_pid_to_str (waiton_ptid
).c_str ());
3493 infrun_debug_printf (" %d.%ld.%ld [%s],",
3497 target_pid_to_str (result_ptid
).c_str ());
3498 infrun_debug_printf (" %s", target_waitstatus_to_string (ws
).c_str ());
3501 /* Select a thread at random, out of those which are resumed and have
3504 static struct thread_info
*
3505 random_pending_event_thread (inferior
*inf
, ptid_t waiton_ptid
)
3509 auto has_event
= [&] (thread_info
*tp
)
3511 return (tp
->ptid
.matches (waiton_ptid
)
3513 && tp
->suspend
.waitstatus_pending_p
);
3516 /* First see how many events we have. Count only resumed threads
3517 that have an event pending. */
3518 for (thread_info
*tp
: inf
->non_exited_threads ())
3522 if (num_events
== 0)
3525 /* Now randomly pick a thread out of those that have had events. */
3526 int random_selector
= (int) ((num_events
* (double) rand ())
3527 / (RAND_MAX
+ 1.0));
3530 infrun_debug_printf ("Found %d events, selecting #%d",
3531 num_events
, random_selector
);
3533 /* Select the Nth thread that has had an event. */
3534 for (thread_info
*tp
: inf
->non_exited_threads ())
3536 if (random_selector
-- == 0)
3539 gdb_assert_not_reached ("event thread not found");
3542 /* Wrapper for target_wait that first checks whether threads have
3543 pending statuses to report before actually asking the target for
3544 more events. INF is the inferior we're using to call target_wait
3548 do_target_wait_1 (inferior
*inf
, ptid_t ptid
,
3549 target_waitstatus
*status
, target_wait_flags options
)
3552 struct thread_info
*tp
;
3554 /* We know that we are looking for an event in the target of inferior
3555 INF, but we don't know which thread the event might come from. As
3556 such we want to make sure that INFERIOR_PTID is reset so that none of
3557 the wait code relies on it - doing so is always a mistake. */
3558 switch_to_inferior_no_thread (inf
);
3560 /* First check if there is a resumed thread with a wait status
3562 if (ptid
== minus_one_ptid
|| ptid
.is_pid ())
3564 tp
= random_pending_event_thread (inf
, ptid
);
3568 infrun_debug_printf ("Waiting for specific thread %s.",
3569 target_pid_to_str (ptid
).c_str ());
3571 /* We have a specific thread to check. */
3572 tp
= find_thread_ptid (inf
, ptid
);
3573 gdb_assert (tp
!= NULL
);
3574 if (!tp
->suspend
.waitstatus_pending_p
)
3579 && (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3580 || tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
3582 struct regcache
*regcache
= get_thread_regcache (tp
);
3583 struct gdbarch
*gdbarch
= regcache
->arch ();
3587 pc
= regcache_read_pc (regcache
);
3589 if (pc
!= tp
->suspend
.stop_pc
)
3591 infrun_debug_printf ("PC of %s changed. was=%s, now=%s",
3592 target_pid_to_str (tp
->ptid
).c_str (),
3593 paddress (gdbarch
, tp
->suspend
.stop_pc
),
3594 paddress (gdbarch
, pc
));
3597 else if (!breakpoint_inserted_here_p (regcache
->aspace (), pc
))
3599 infrun_debug_printf ("previous breakpoint of %s, at %s gone",
3600 target_pid_to_str (tp
->ptid
).c_str (),
3601 paddress (gdbarch
, pc
));
3608 infrun_debug_printf ("pending event of %s cancelled.",
3609 target_pid_to_str (tp
->ptid
).c_str ());
3611 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_SPURIOUS
;
3612 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3618 infrun_debug_printf ("Using pending wait status %s for %s.",
3619 target_waitstatus_to_string
3620 (&tp
->suspend
.waitstatus
).c_str (),
3621 target_pid_to_str (tp
->ptid
).c_str ());
3623 /* Now that we've selected our final event LWP, un-adjust its PC
3624 if it was a software breakpoint (and the target doesn't
3625 always adjust the PC itself). */
3626 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3627 && !target_supports_stopped_by_sw_breakpoint ())
3629 struct regcache
*regcache
;
3630 struct gdbarch
*gdbarch
;
3633 regcache
= get_thread_regcache (tp
);
3634 gdbarch
= regcache
->arch ();
3636 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3641 pc
= regcache_read_pc (regcache
);
3642 regcache_write_pc (regcache
, pc
+ decr_pc
);
3646 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3647 *status
= tp
->suspend
.waitstatus
;
3648 tp
->suspend
.waitstatus_pending_p
= 0;
3650 /* Wake up the event loop again, until all pending events are
3652 if (target_is_async_p ())
3653 mark_async_event_handler (infrun_async_inferior_event_token
);
3657 /* But if we don't find one, we'll have to wait. */
3659 /* We can't ask a non-async target to do a non-blocking wait, so this will be
3661 if (!target_can_async_p ())
3662 options
&= ~TARGET_WNOHANG
;
3664 if (deprecated_target_wait_hook
)
3665 event_ptid
= deprecated_target_wait_hook (ptid
, status
, options
);
3667 event_ptid
= target_wait (ptid
, status
, options
);
3672 /* Wrapper for target_wait that first checks whether threads have
3673 pending statuses to report before actually asking the target for
3674 more events. Polls for events from all inferiors/targets. */
3677 do_target_wait (execution_control_state
*ecs
, target_wait_flags options
)
3679 int num_inferiors
= 0;
3680 int random_selector
;
3682 /* For fairness, we pick the first inferior/target to poll at random
3683 out of all inferiors that may report events, and then continue
3684 polling the rest of the inferior list starting from that one in a
3685 circular fashion until the whole list is polled once. */
3687 auto inferior_matches
= [] (inferior
*inf
)
3689 return inf
->process_target () != nullptr;
3692 /* First see how many matching inferiors we have. */
3693 for (inferior
*inf
: all_inferiors ())
3694 if (inferior_matches (inf
))
3697 if (num_inferiors
== 0)
3699 ecs
->ws
.kind
= TARGET_WAITKIND_IGNORE
;
3703 /* Now randomly pick an inferior out of those that matched. */
3704 random_selector
= (int)
3705 ((num_inferiors
* (double) rand ()) / (RAND_MAX
+ 1.0));
3707 if (num_inferiors
> 1)
3708 infrun_debug_printf ("Found %d inferiors, starting at #%d",
3709 num_inferiors
, random_selector
);
3711 /* Select the Nth inferior that matched. */
3713 inferior
*selected
= nullptr;
3715 for (inferior
*inf
: all_inferiors ())
3716 if (inferior_matches (inf
))
3717 if (random_selector
-- == 0)
3723 /* Now poll for events out of each of the matching inferior's
3724 targets, starting from the selected one. */
3726 auto do_wait
= [&] (inferior
*inf
)
3728 ecs
->ptid
= do_target_wait_1 (inf
, minus_one_ptid
, &ecs
->ws
, options
);
3729 ecs
->target
= inf
->process_target ();
3730 return (ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
);
3733 /* Needed in 'all-stop + target-non-stop' mode, because we end up
3734 here spuriously after the target is all stopped and we've already
3735 reported the stop to the user, polling for events. */
3736 scoped_restore_current_thread restore_thread
;
3738 int inf_num
= selected
->num
;
3739 for (inferior
*inf
= selected
; inf
!= NULL
; inf
= inf
->next
)
3740 if (inferior_matches (inf
))
3744 for (inferior
*inf
= inferior_list
;
3745 inf
!= NULL
&& inf
->num
< inf_num
;
3747 if (inferior_matches (inf
))
3751 ecs
->ws
.kind
= TARGET_WAITKIND_IGNORE
;
3755 /* An event reported by wait_one. */
3757 struct wait_one_event
3759 /* The target the event came out of. */
3760 process_stratum_target
*target
;
3762 /* The PTID the event was for. */
3765 /* The waitstatus. */
3766 target_waitstatus ws
;
3769 static bool handle_one (const wait_one_event
&event
);
3770 static void restart_threads (struct thread_info
*event_thread
,
3771 inferior
*inf
= nullptr);
3773 /* Prepare and stabilize the inferior for detaching it. E.g.,
3774 detaching while a thread is displaced stepping is a recipe for
3775 crashing it, as nothing would readjust the PC out of the scratch
3779 prepare_for_detach (void)
3781 struct inferior
*inf
= current_inferior ();
3782 ptid_t pid_ptid
= ptid_t (inf
->pid
);
3783 scoped_restore_current_thread restore_thread
;
3785 scoped_restore restore_detaching
= make_scoped_restore (&inf
->detaching
, true);
3787 /* Remove all threads of INF from the global step-over chain. We
3788 want to stop any ongoing step-over, not start any new one. */
3790 for (thread_info
*tp
= global_thread_step_over_chain_head
;
3794 next
= global_thread_step_over_chain_next (tp
);
3796 global_thread_step_over_chain_remove (tp
);
3799 /* If we were already in the middle of an inline step-over, and the
3800 thread stepping belongs to the inferior we're detaching, we need
3801 to restart the threads of other inferiors. */
3802 if (step_over_info
.thread
!= -1)
3804 infrun_debug_printf ("inline step-over in-process while detaching");
3806 thread_info
*thr
= find_thread_global_id (step_over_info
.thread
);
3807 if (thr
->inf
== inf
)
3809 /* Since we removed threads of INF from the step-over chain,
3810 we know this won't start a step-over for INF. */
3811 clear_step_over_info ();
3813 if (target_is_non_stop_p ())
3815 /* Start a new step-over in another thread if there's
3816 one that needs it. */
3819 /* Restart all other threads (except the
3820 previously-stepping thread, since that one is still
3822 if (!step_over_info_valid_p ())
3823 restart_threads (thr
);
3828 if (displaced_step_in_progress (inf
))
3830 infrun_debug_printf ("displaced-stepping in-process while detaching");
3832 /* Stop threads currently displaced stepping, aborting it. */
3834 for (thread_info
*thr
: inf
->non_exited_threads ())
3836 if (thr
->displaced_step_state
.in_progress ())
3840 if (!thr
->stop_requested
)
3842 target_stop (thr
->ptid
);
3843 thr
->stop_requested
= true;
3847 thr
->resumed
= false;
3851 while (displaced_step_in_progress (inf
))
3853 wait_one_event event
;
3855 event
.target
= inf
->process_target ();
3856 event
.ptid
= do_target_wait_1 (inf
, pid_ptid
, &event
.ws
, 0);
3859 print_target_wait_results (pid_ptid
, event
.ptid
, &event
.ws
);
3864 /* It's OK to leave some of the threads of INF stopped, since
3865 they'll be detached shortly. */
3869 /* Wait for control to return from inferior to debugger.
3871 If inferior gets a signal, we may decide to start it up again
3872 instead of returning. That is why there is a loop in this function.
3873 When this function actually returns it means the inferior
3874 should be left stopped and GDB should read more commands. */
3877 wait_for_inferior (inferior
*inf
)
3879 infrun_debug_printf ("wait_for_inferior ()");
3881 SCOPE_EXIT
{ delete_just_stopped_threads_infrun_breakpoints (); };
3883 /* If an error happens while handling the event, propagate GDB's
3884 knowledge of the executing state to the frontend/user running
3886 scoped_finish_thread_state finish_state
3887 (inf
->process_target (), minus_one_ptid
);
3891 struct execution_control_state ecss
;
3892 struct execution_control_state
*ecs
= &ecss
;
3894 memset (ecs
, 0, sizeof (*ecs
));
3896 overlay_cache_invalid
= 1;
3898 /* Flush target cache before starting to handle each event.
3899 Target was running and cache could be stale. This is just a
3900 heuristic. Running threads may modify target memory, but we
3901 don't get any event. */
3902 target_dcache_invalidate ();
3904 ecs
->ptid
= do_target_wait_1 (inf
, minus_one_ptid
, &ecs
->ws
, 0);
3905 ecs
->target
= inf
->process_target ();
3908 print_target_wait_results (minus_one_ptid
, ecs
->ptid
, &ecs
->ws
);
3910 /* Now figure out what to do with the result of the result. */
3911 handle_inferior_event (ecs
);
3913 if (!ecs
->wait_some_more
)
3917 /* No error, don't finish the state yet. */
3918 finish_state
.release ();
3921 /* Cleanup that reinstalls the readline callback handler, if the
3922 target is running in the background. If while handling the target
3923 event something triggered a secondary prompt, like e.g., a
3924 pagination prompt, we'll have removed the callback handler (see
3925 gdb_readline_wrapper_line). Need to do this as we go back to the
3926 event loop, ready to process further input. Note this has no
3927 effect if the handler hasn't actually been removed, because calling
3928 rl_callback_handler_install resets the line buffer, thus losing
3932 reinstall_readline_callback_handler_cleanup ()
3934 struct ui
*ui
= current_ui
;
3938 /* We're not going back to the top level event loop yet. Don't
3939 install the readline callback, as it'd prep the terminal,
3940 readline-style (raw, noecho) (e.g., --batch). We'll install
3941 it the next time the prompt is displayed, when we're ready
3946 if (ui
->command_editing
&& ui
->prompt_state
!= PROMPT_BLOCKED
)
3947 gdb_rl_callback_handler_reinstall ();
3950 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3951 that's just the event thread. In all-stop, that's all threads. */
3954 clean_up_just_stopped_threads_fsms (struct execution_control_state
*ecs
)
3956 if (ecs
->event_thread
!= NULL
3957 && ecs
->event_thread
->thread_fsm
!= NULL
)
3958 ecs
->event_thread
->thread_fsm
->clean_up (ecs
->event_thread
);
3962 for (thread_info
*thr
: all_non_exited_threads ())
3964 if (thr
->thread_fsm
== NULL
)
3966 if (thr
== ecs
->event_thread
)
3969 switch_to_thread (thr
);
3970 thr
->thread_fsm
->clean_up (thr
);
3973 if (ecs
->event_thread
!= NULL
)
3974 switch_to_thread (ecs
->event_thread
);
3978 /* Helper for all_uis_check_sync_execution_done that works on the
3982 check_curr_ui_sync_execution_done (void)
3984 struct ui
*ui
= current_ui
;
3986 if (ui
->prompt_state
== PROMPT_NEEDED
3988 && !gdb_in_secondary_prompt_p (ui
))
3990 target_terminal::ours ();
3991 gdb::observers::sync_execution_done
.notify ();
3992 ui_register_input_event_handler (ui
);
3999 all_uis_check_sync_execution_done (void)
4001 SWITCH_THRU_ALL_UIS ()
4003 check_curr_ui_sync_execution_done ();
4010 all_uis_on_sync_execution_starting (void)
4012 SWITCH_THRU_ALL_UIS ()
4014 if (current_ui
->prompt_state
== PROMPT_NEEDED
)
4015 async_disable_stdin ();
4019 /* Asynchronous version of wait_for_inferior. It is called by the
4020 event loop whenever a change of state is detected on the file
4021 descriptor corresponding to the target. It can be called more than
4022 once to complete a single execution command. In such cases we need
4023 to keep the state in a global variable ECSS. If it is the last time
4024 that this function is called for a single execution command, then
4025 report to the user that the inferior has stopped, and do the
4026 necessary cleanups. */
4029 fetch_inferior_event ()
4031 INFRUN_SCOPED_DEBUG_ENTER_EXIT
;
4033 struct execution_control_state ecss
;
4034 struct execution_control_state
*ecs
= &ecss
;
4037 memset (ecs
, 0, sizeof (*ecs
));
4039 /* Events are always processed with the main UI as current UI. This
4040 way, warnings, debug output, etc. are always consistently sent to
4041 the main console. */
4042 scoped_restore save_ui
= make_scoped_restore (¤t_ui
, main_ui
);
4044 /* Temporarily disable pagination. Otherwise, the user would be
4045 given an option to press 'q' to quit, which would cause an early
4046 exit and could leave GDB in a half-baked state. */
4047 scoped_restore save_pagination
4048 = make_scoped_restore (&pagination_enabled
, false);
4050 /* End up with readline processing input, if necessary. */
4052 SCOPE_EXIT
{ reinstall_readline_callback_handler_cleanup (); };
4054 /* We're handling a live event, so make sure we're doing live
4055 debugging. If we're looking at traceframes while the target is
4056 running, we're going to need to get back to that mode after
4057 handling the event. */
4058 gdb::optional
<scoped_restore_current_traceframe
> maybe_restore_traceframe
;
4061 maybe_restore_traceframe
.emplace ();
4062 set_current_traceframe (-1);
4065 /* The user/frontend should not notice a thread switch due to
4066 internal events. Make sure we revert to the user selected
4067 thread and frame after handling the event and running any
4068 breakpoint commands. */
4069 scoped_restore_current_thread restore_thread
;
4071 overlay_cache_invalid
= 1;
4072 /* Flush target cache before starting to handle each event. Target
4073 was running and cache could be stale. This is just a heuristic.
4074 Running threads may modify target memory, but we don't get any
4076 target_dcache_invalidate ();
4078 scoped_restore save_exec_dir
4079 = make_scoped_restore (&execution_direction
,
4080 target_execution_direction ());
4082 /* Allow targets to pause their resumed threads while we handle
4084 scoped_disable_commit_resumed
disable_commit_resumed ("handling event");
4086 if (!do_target_wait (ecs
, TARGET_WNOHANG
))
4088 infrun_debug_printf ("do_target_wait returned no event");
4089 disable_commit_resumed
.reset_and_commit ();
4093 gdb_assert (ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
);
4095 /* Switch to the target that generated the event, so we can do
4097 switch_to_target_no_thread (ecs
->target
);
4100 print_target_wait_results (minus_one_ptid
, ecs
->ptid
, &ecs
->ws
);
4102 /* If an error happens while handling the event, propagate GDB's
4103 knowledge of the executing state to the frontend/user running
4105 ptid_t finish_ptid
= !target_is_non_stop_p () ? minus_one_ptid
: ecs
->ptid
;
4106 scoped_finish_thread_state
finish_state (ecs
->target
, finish_ptid
);
4108 /* Get executed before scoped_restore_current_thread above to apply
4109 still for the thread which has thrown the exception. */
4110 auto defer_bpstat_clear
4111 = make_scope_exit (bpstat_clear_actions
);
4112 auto defer_delete_threads
4113 = make_scope_exit (delete_just_stopped_threads_infrun_breakpoints
);
4115 /* Now figure out what to do with the result of the result. */
4116 handle_inferior_event (ecs
);
4118 if (!ecs
->wait_some_more
)
4120 struct inferior
*inf
= find_inferior_ptid (ecs
->target
, ecs
->ptid
);
4121 bool should_stop
= true;
4122 struct thread_info
*thr
= ecs
->event_thread
;
4124 delete_just_stopped_threads_infrun_breakpoints ();
4128 struct thread_fsm
*thread_fsm
= thr
->thread_fsm
;
4130 if (thread_fsm
!= NULL
)
4131 should_stop
= thread_fsm
->should_stop (thr
);
4140 bool should_notify_stop
= true;
4143 clean_up_just_stopped_threads_fsms (ecs
);
4145 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
4146 should_notify_stop
= thr
->thread_fsm
->should_notify_stop ();
4148 if (should_notify_stop
)
4150 /* We may not find an inferior if this was a process exit. */
4151 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
4152 proceeded
= normal_stop ();
4157 inferior_event_handler (INF_EXEC_COMPLETE
);
4161 /* If we got a TARGET_WAITKIND_NO_RESUMED event, then the
4162 previously selected thread is gone. We have two
4163 choices - switch to no thread selected, or restore the
4164 previously selected thread (now exited). We chose the
4165 later, just because that's what GDB used to do. After
4166 this, "info threads" says "The current thread <Thread
4167 ID 2> has terminated." instead of "No thread
4171 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
4172 restore_thread
.dont_restore ();
4176 defer_delete_threads
.release ();
4177 defer_bpstat_clear
.release ();
4179 /* No error, don't finish the thread states yet. */
4180 finish_state
.release ();
4182 disable_commit_resumed
.reset_and_commit ();
4184 /* This scope is used to ensure that readline callbacks are
4185 reinstalled here. */
4188 /* If a UI was in sync execution mode, and now isn't, restore its
4189 prompt (a synchronous execution command has finished, and we're
4190 ready for input). */
4191 all_uis_check_sync_execution_done ();
4194 && exec_done_display_p
4195 && (inferior_ptid
== null_ptid
4196 || inferior_thread ()->state
!= THREAD_RUNNING
))
4197 printf_unfiltered (_("completed.\n"));
4203 set_step_info (thread_info
*tp
, struct frame_info
*frame
,
4204 struct symtab_and_line sal
)
4206 /* This can be removed once this function no longer implicitly relies on the
4207 inferior_ptid value. */
4208 gdb_assert (inferior_ptid
== tp
->ptid
);
4210 tp
->control
.step_frame_id
= get_frame_id (frame
);
4211 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
4213 tp
->current_symtab
= sal
.symtab
;
4214 tp
->current_line
= sal
.line
;
4217 /* Clear context switchable stepping state. */
4220 init_thread_stepping_state (struct thread_info
*tss
)
4222 tss
->stepped_breakpoint
= 0;
4223 tss
->stepping_over_breakpoint
= 0;
4224 tss
->stepping_over_watchpoint
= 0;
4225 tss
->step_after_step_resume_breakpoint
= 0;
4231 set_last_target_status (process_stratum_target
*target
, ptid_t ptid
,
4232 target_waitstatus status
)
4234 target_last_proc_target
= target
;
4235 target_last_wait_ptid
= ptid
;
4236 target_last_waitstatus
= status
;
4242 get_last_target_status (process_stratum_target
**target
, ptid_t
*ptid
,
4243 target_waitstatus
*status
)
4245 if (target
!= nullptr)
4246 *target
= target_last_proc_target
;
4247 if (ptid
!= nullptr)
4248 *ptid
= target_last_wait_ptid
;
4249 if (status
!= nullptr)
4250 *status
= target_last_waitstatus
;
4256 nullify_last_target_wait_ptid (void)
4258 target_last_proc_target
= nullptr;
4259 target_last_wait_ptid
= minus_one_ptid
;
4260 target_last_waitstatus
= {};
4263 /* Switch thread contexts. */
4266 context_switch (execution_control_state
*ecs
)
4268 if (ecs
->ptid
!= inferior_ptid
4269 && (inferior_ptid
== null_ptid
4270 || ecs
->event_thread
!= inferior_thread ()))
4272 infrun_debug_printf ("Switching context from %s to %s",
4273 target_pid_to_str (inferior_ptid
).c_str (),
4274 target_pid_to_str (ecs
->ptid
).c_str ());
4277 switch_to_thread (ecs
->event_thread
);
4280 /* If the target can't tell whether we've hit breakpoints
4281 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
4282 check whether that could have been caused by a breakpoint. If so,
4283 adjust the PC, per gdbarch_decr_pc_after_break. */
4286 adjust_pc_after_break (struct thread_info
*thread
,
4287 struct target_waitstatus
*ws
)
4289 struct regcache
*regcache
;
4290 struct gdbarch
*gdbarch
;
4291 CORE_ADDR breakpoint_pc
, decr_pc
;
4293 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
4294 we aren't, just return.
4296 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
4297 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
4298 implemented by software breakpoints should be handled through the normal
4301 NOTE drow/2004-01-31: On some targets, breakpoints may generate
4302 different signals (SIGILL or SIGEMT for instance), but it is less
4303 clear where the PC is pointing afterwards. It may not match
4304 gdbarch_decr_pc_after_break. I don't know any specific target that
4305 generates these signals at breakpoints (the code has been in GDB since at
4306 least 1992) so I can not guess how to handle them here.
4308 In earlier versions of GDB, a target with
4309 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
4310 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
4311 target with both of these set in GDB history, and it seems unlikely to be
4312 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
4314 if (ws
->kind
!= TARGET_WAITKIND_STOPPED
)
4317 if (ws
->value
.sig
!= GDB_SIGNAL_TRAP
)
4320 /* In reverse execution, when a breakpoint is hit, the instruction
4321 under it has already been de-executed. The reported PC always
4322 points at the breakpoint address, so adjusting it further would
4323 be wrong. E.g., consider this case on a decr_pc_after_break == 1
4326 B1 0x08000000 : INSN1
4327 B2 0x08000001 : INSN2
4329 PC -> 0x08000003 : INSN4
4331 Say you're stopped at 0x08000003 as above. Reverse continuing
4332 from that point should hit B2 as below. Reading the PC when the
4333 SIGTRAP is reported should read 0x08000001 and INSN2 should have
4334 been de-executed already.
4336 B1 0x08000000 : INSN1
4337 B2 PC -> 0x08000001 : INSN2
4341 We can't apply the same logic as for forward execution, because
4342 we would wrongly adjust the PC to 0x08000000, since there's a
4343 breakpoint at PC - 1. We'd then report a hit on B1, although
4344 INSN1 hadn't been de-executed yet. Doing nothing is the correct
4346 if (execution_direction
== EXEC_REVERSE
)
4349 /* If the target can tell whether the thread hit a SW breakpoint,
4350 trust it. Targets that can tell also adjust the PC
4352 if (target_supports_stopped_by_sw_breakpoint ())
4355 /* Note that relying on whether a breakpoint is planted in memory to
4356 determine this can fail. E.g,. the breakpoint could have been
4357 removed since. Or the thread could have been told to step an
4358 instruction the size of a breakpoint instruction, and only
4359 _after_ was a breakpoint inserted at its address. */
4361 /* If this target does not decrement the PC after breakpoints, then
4362 we have nothing to do. */
4363 regcache
= get_thread_regcache (thread
);
4364 gdbarch
= regcache
->arch ();
4366 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
4370 const address_space
*aspace
= regcache
->aspace ();
4372 /* Find the location where (if we've hit a breakpoint) the
4373 breakpoint would be. */
4374 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
4376 /* If the target can't tell whether a software breakpoint triggered,
4377 fallback to figuring it out based on breakpoints we think were
4378 inserted in the target, and on whether the thread was stepped or
4381 /* Check whether there actually is a software breakpoint inserted at
4384 If in non-stop mode, a race condition is possible where we've
4385 removed a breakpoint, but stop events for that breakpoint were
4386 already queued and arrive later. To suppress those spurious
4387 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
4388 and retire them after a number of stop events are reported. Note
4389 this is an heuristic and can thus get confused. The real fix is
4390 to get the "stopped by SW BP and needs adjustment" info out of
4391 the target/kernel (and thus never reach here; see above). */
4392 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
4393 || (target_is_non_stop_p ()
4394 && moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
4396 gdb::optional
<scoped_restore_tmpl
<int>> restore_operation_disable
;
4398 if (record_full_is_used ())
4399 restore_operation_disable
.emplace
4400 (record_full_gdb_operation_disable_set ());
4402 /* When using hardware single-step, a SIGTRAP is reported for both
4403 a completed single-step and a software breakpoint. Need to
4404 differentiate between the two, as the latter needs adjusting
4405 but the former does not.
4407 The SIGTRAP can be due to a completed hardware single-step only if
4408 - we didn't insert software single-step breakpoints
4409 - this thread is currently being stepped
4411 If any of these events did not occur, we must have stopped due
4412 to hitting a software breakpoint, and have to back up to the
4415 As a special case, we could have hardware single-stepped a
4416 software breakpoint. In this case (prev_pc == breakpoint_pc),
4417 we also need to back up to the breakpoint address. */
4419 if (thread_has_single_step_breakpoints_set (thread
)
4420 || !currently_stepping (thread
)
4421 || (thread
->stepped_breakpoint
4422 && thread
->prev_pc
== breakpoint_pc
))
4423 regcache_write_pc (regcache
, breakpoint_pc
);
4428 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
4430 for (frame
= get_prev_frame (frame
);
4432 frame
= get_prev_frame (frame
))
4434 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
4437 if (get_frame_type (frame
) != INLINE_FRAME
)
4444 /* Look for an inline frame that is marked for skip.
4445 If PREV_FRAME is TRUE start at the previous frame,
4446 otherwise start at the current frame. Stop at the
4447 first non-inline frame, or at the frame where the
4451 inline_frame_is_marked_for_skip (bool prev_frame
, struct thread_info
*tp
)
4453 struct frame_info
*frame
= get_current_frame ();
4456 frame
= get_prev_frame (frame
);
4458 for (; frame
!= NULL
; frame
= get_prev_frame (frame
))
4460 const char *fn
= NULL
;
4461 symtab_and_line sal
;
4464 if (frame_id_eq (get_frame_id (frame
), tp
->control
.step_frame_id
))
4466 if (get_frame_type (frame
) != INLINE_FRAME
)
4469 sal
= find_frame_sal (frame
);
4470 sym
= get_frame_function (frame
);
4473 fn
= sym
->print_name ();
4476 && function_name_is_marked_for_skip (fn
, sal
))
4483 /* If the event thread has the stop requested flag set, pretend it
4484 stopped for a GDB_SIGNAL_0 (i.e., as if it stopped due to
4488 handle_stop_requested (struct execution_control_state
*ecs
)
4490 if (ecs
->event_thread
->stop_requested
)
4492 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
4493 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
4494 handle_signal_stop (ecs
);
4500 /* Auxiliary function that handles syscall entry/return events.
4501 It returns true if the inferior should keep going (and GDB
4502 should ignore the event), or false if the event deserves to be
4506 handle_syscall_event (struct execution_control_state
*ecs
)
4508 struct regcache
*regcache
;
4511 context_switch (ecs
);
4513 regcache
= get_thread_regcache (ecs
->event_thread
);
4514 syscall_number
= ecs
->ws
.value
.syscall_number
;
4515 ecs
->event_thread
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4517 if (catch_syscall_enabled () > 0
4518 && catching_syscall_number (syscall_number
) > 0)
4520 infrun_debug_printf ("syscall number=%d", syscall_number
);
4522 ecs
->event_thread
->control
.stop_bpstat
4523 = bpstat_stop_status (regcache
->aspace (),
4524 ecs
->event_thread
->suspend
.stop_pc
,
4525 ecs
->event_thread
, &ecs
->ws
);
4527 if (handle_stop_requested (ecs
))
4530 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4532 /* Catchpoint hit. */
4537 if (handle_stop_requested (ecs
))
4540 /* If no catchpoint triggered for this, then keep going. */
4546 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4549 fill_in_stop_func (struct gdbarch
*gdbarch
,
4550 struct execution_control_state
*ecs
)
4552 if (!ecs
->stop_func_filled_in
)
4555 const general_symbol_info
*gsi
;
4557 /* Don't care about return value; stop_func_start and stop_func_name
4558 will both be 0 if it doesn't work. */
4559 find_pc_partial_function_sym (ecs
->event_thread
->suspend
.stop_pc
,
4561 &ecs
->stop_func_start
,
4562 &ecs
->stop_func_end
,
4564 ecs
->stop_func_name
= gsi
== nullptr ? nullptr : gsi
->print_name ();
4566 /* The call to find_pc_partial_function, above, will set
4567 stop_func_start and stop_func_end to the start and end
4568 of the range containing the stop pc. If this range
4569 contains the entry pc for the block (which is always the
4570 case for contiguous blocks), advance stop_func_start past
4571 the function's start offset and entrypoint. Note that
4572 stop_func_start is NOT advanced when in a range of a
4573 non-contiguous block that does not contain the entry pc. */
4574 if (block
!= nullptr
4575 && ecs
->stop_func_start
<= BLOCK_ENTRY_PC (block
)
4576 && BLOCK_ENTRY_PC (block
) < ecs
->stop_func_end
)
4578 ecs
->stop_func_start
4579 += gdbarch_deprecated_function_start_offset (gdbarch
);
4581 if (gdbarch_skip_entrypoint_p (gdbarch
))
4582 ecs
->stop_func_start
4583 = gdbarch_skip_entrypoint (gdbarch
, ecs
->stop_func_start
);
4586 ecs
->stop_func_filled_in
= 1;
4591 /* Return the STOP_SOON field of the inferior pointed at by ECS. */
4593 static enum stop_kind
4594 get_inferior_stop_soon (execution_control_state
*ecs
)
4596 struct inferior
*inf
= find_inferior_ptid (ecs
->target
, ecs
->ptid
);
4598 gdb_assert (inf
!= NULL
);
4599 return inf
->control
.stop_soon
;
4602 /* Poll for one event out of the current target. Store the resulting
4603 waitstatus in WS, and return the event ptid. Does not block. */
4606 poll_one_curr_target (struct target_waitstatus
*ws
)
4610 overlay_cache_invalid
= 1;
4612 /* Flush target cache before starting to handle each event.
4613 Target was running and cache could be stale. This is just a
4614 heuristic. Running threads may modify target memory, but we
4615 don't get any event. */
4616 target_dcache_invalidate ();
4618 if (deprecated_target_wait_hook
)
4619 event_ptid
= deprecated_target_wait_hook (minus_one_ptid
, ws
, TARGET_WNOHANG
);
4621 event_ptid
= target_wait (minus_one_ptid
, ws
, TARGET_WNOHANG
);
4624 print_target_wait_results (minus_one_ptid
, event_ptid
, ws
);
4629 /* Wait for one event out of any target. */
4631 static wait_one_event
4636 for (inferior
*inf
: all_inferiors ())
4638 process_stratum_target
*target
= inf
->process_target ();
4640 || !target
->is_async_p ()
4641 || !target
->threads_executing
)
4644 switch_to_inferior_no_thread (inf
);
4646 wait_one_event event
;
4647 event
.target
= target
;
4648 event
.ptid
= poll_one_curr_target (&event
.ws
);
4650 if (event
.ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4652 /* If nothing is resumed, remove the target from the
4656 else if (event
.ws
.kind
!= TARGET_WAITKIND_IGNORE
)
4660 /* Block waiting for some event. */
4667 for (inferior
*inf
: all_inferiors ())
4669 process_stratum_target
*target
= inf
->process_target ();
4671 || !target
->is_async_p ()
4672 || !target
->threads_executing
)
4675 int fd
= target
->async_wait_fd ();
4676 FD_SET (fd
, &readfds
);
4683 /* No waitable targets left. All must be stopped. */
4684 return {NULL
, minus_one_ptid
, {TARGET_WAITKIND_NO_RESUMED
}};
4689 int numfds
= interruptible_select (nfds
, &readfds
, 0, NULL
, 0);
4695 perror_with_name ("interruptible_select");
4700 /* Save the thread's event and stop reason to process it later. */
4703 save_waitstatus (struct thread_info
*tp
, const target_waitstatus
*ws
)
4705 infrun_debug_printf ("saving status %s for %d.%ld.%ld",
4706 target_waitstatus_to_string (ws
).c_str (),
4711 /* Record for later. */
4712 tp
->suspend
.waitstatus
= *ws
;
4713 tp
->suspend
.waitstatus_pending_p
= 1;
4715 if (ws
->kind
== TARGET_WAITKIND_STOPPED
4716 && ws
->value
.sig
== GDB_SIGNAL_TRAP
)
4718 struct regcache
*regcache
= get_thread_regcache (tp
);
4719 const address_space
*aspace
= regcache
->aspace ();
4720 CORE_ADDR pc
= regcache_read_pc (regcache
);
4722 adjust_pc_after_break (tp
, &tp
->suspend
.waitstatus
);
4724 scoped_restore_current_thread restore_thread
;
4725 switch_to_thread (tp
);
4727 if (target_stopped_by_watchpoint ())
4729 tp
->suspend
.stop_reason
4730 = TARGET_STOPPED_BY_WATCHPOINT
;
4732 else if (target_supports_stopped_by_sw_breakpoint ()
4733 && target_stopped_by_sw_breakpoint ())
4735 tp
->suspend
.stop_reason
4736 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4738 else if (target_supports_stopped_by_hw_breakpoint ()
4739 && target_stopped_by_hw_breakpoint ())
4741 tp
->suspend
.stop_reason
4742 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4744 else if (!target_supports_stopped_by_hw_breakpoint ()
4745 && hardware_breakpoint_inserted_here_p (aspace
,
4748 tp
->suspend
.stop_reason
4749 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4751 else if (!target_supports_stopped_by_sw_breakpoint ()
4752 && software_breakpoint_inserted_here_p (aspace
,
4755 tp
->suspend
.stop_reason
4756 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4758 else if (!thread_has_single_step_breakpoints_set (tp
)
4759 && currently_stepping (tp
))
4761 tp
->suspend
.stop_reason
4762 = TARGET_STOPPED_BY_SINGLE_STEP
;
4767 /* Mark the non-executing threads accordingly. In all-stop, all
4768 threads of all processes are stopped when we get any event
4769 reported. In non-stop mode, only the event thread stops. */
4772 mark_non_executing_threads (process_stratum_target
*target
,
4774 struct target_waitstatus ws
)
4778 if (!target_is_non_stop_p ())
4779 mark_ptid
= minus_one_ptid
;
4780 else if (ws
.kind
== TARGET_WAITKIND_SIGNALLED
4781 || ws
.kind
== TARGET_WAITKIND_EXITED
)
4783 /* If we're handling a process exit in non-stop mode, even
4784 though threads haven't been deleted yet, one would think
4785 that there is nothing to do, as threads of the dead process
4786 will be soon deleted, and threads of any other process were
4787 left running. However, on some targets, threads survive a
4788 process exit event. E.g., for the "checkpoint" command,
4789 when the current checkpoint/fork exits, linux-fork.c
4790 automatically switches to another fork from within
4791 target_mourn_inferior, by associating the same
4792 inferior/thread to another fork. We haven't mourned yet at
4793 this point, but we must mark any threads left in the
4794 process as not-executing so that finish_thread_state marks
4795 them stopped (in the user's perspective) if/when we present
4796 the stop to the user. */
4797 mark_ptid
= ptid_t (event_ptid
.pid ());
4800 mark_ptid
= event_ptid
;
4802 set_executing (target
, mark_ptid
, false);
4804 /* Likewise the resumed flag. */
4805 set_resumed (target
, mark_ptid
, false);
4808 /* Handle one event after stopping threads. If the eventing thread
4809 reports back any interesting event, we leave it pending. If the
4810 eventing thread was in the middle of a displaced step, we
4811 cancel/finish it, and unless the thread's inferior is being
4812 detached, put the thread back in the step-over chain. Returns true
4813 if there are no resumed threads left in the target (thus there's no
4814 point in waiting further), false otherwise. */
4817 handle_one (const wait_one_event
&event
)
4820 ("%s %s", target_waitstatus_to_string (&event
.ws
).c_str (),
4821 target_pid_to_str (event
.ptid
).c_str ());
4823 if (event
.ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4825 /* All resumed threads exited. */
4828 else if (event
.ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
4829 || event
.ws
.kind
== TARGET_WAITKIND_EXITED
4830 || event
.ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
4832 /* One thread/process exited/signalled. */
4834 thread_info
*t
= nullptr;
4836 /* The target may have reported just a pid. If so, try
4837 the first non-exited thread. */
4838 if (event
.ptid
.is_pid ())
4840 int pid
= event
.ptid
.pid ();
4841 inferior
*inf
= find_inferior_pid (event
.target
, pid
);
4842 for (thread_info
*tp
: inf
->non_exited_threads ())
4848 /* If there is no available thread, the event would
4849 have to be appended to a per-inferior event list,
4850 which does not exist (and if it did, we'd have
4851 to adjust run control command to be able to
4852 resume such an inferior). We assert here instead
4853 of going into an infinite loop. */
4854 gdb_assert (t
!= nullptr);
4857 ("using %s", target_pid_to_str (t
->ptid
).c_str ());
4861 t
= find_thread_ptid (event
.target
, event
.ptid
);
4862 /* Check if this is the first time we see this thread.
4863 Don't bother adding if it individually exited. */
4865 && event
.ws
.kind
!= TARGET_WAITKIND_THREAD_EXITED
)
4866 t
= add_thread (event
.target
, event
.ptid
);
4871 /* Set the threads as non-executing to avoid
4872 another stop attempt on them. */
4873 switch_to_thread_no_regs (t
);
4874 mark_non_executing_threads (event
.target
, event
.ptid
,
4876 save_waitstatus (t
, &event
.ws
);
4877 t
->stop_requested
= false;
4882 thread_info
*t
= find_thread_ptid (event
.target
, event
.ptid
);
4884 t
= add_thread (event
.target
, event
.ptid
);
4886 t
->stop_requested
= 0;
4889 t
->control
.may_range_step
= 0;
4891 /* This may be the first time we see the inferior report
4893 inferior
*inf
= find_inferior_ptid (event
.target
, event
.ptid
);
4894 if (inf
->needs_setup
)
4896 switch_to_thread_no_regs (t
);
4900 if (event
.ws
.kind
== TARGET_WAITKIND_STOPPED
4901 && event
.ws
.value
.sig
== GDB_SIGNAL_0
)
4903 /* We caught the event that we intended to catch, so
4904 there's no event pending. */
4905 t
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
4906 t
->suspend
.waitstatus_pending_p
= 0;
4908 if (displaced_step_finish (t
, GDB_SIGNAL_0
)
4909 == DISPLACED_STEP_FINISH_STATUS_NOT_EXECUTED
)
4911 /* Add it back to the step-over queue. */
4913 ("displaced-step of %s canceled",
4914 target_pid_to_str (t
->ptid
).c_str ());
4916 t
->control
.trap_expected
= 0;
4917 if (!t
->inf
->detaching
)
4918 global_thread_step_over_chain_enqueue (t
);
4923 enum gdb_signal sig
;
4924 struct regcache
*regcache
;
4927 ("target_wait %s, saving status for %d.%ld.%ld",
4928 target_waitstatus_to_string (&event
.ws
).c_str (),
4929 t
->ptid
.pid (), t
->ptid
.lwp (), t
->ptid
.tid ());
4931 /* Record for later. */
4932 save_waitstatus (t
, &event
.ws
);
4934 sig
= (event
.ws
.kind
== TARGET_WAITKIND_STOPPED
4935 ? event
.ws
.value
.sig
: GDB_SIGNAL_0
);
4937 if (displaced_step_finish (t
, sig
)
4938 == DISPLACED_STEP_FINISH_STATUS_NOT_EXECUTED
)
4940 /* Add it back to the step-over queue. */
4941 t
->control
.trap_expected
= 0;
4942 if (!t
->inf
->detaching
)
4943 global_thread_step_over_chain_enqueue (t
);
4946 regcache
= get_thread_regcache (t
);
4947 t
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4949 infrun_debug_printf ("saved stop_pc=%s for %s "
4950 "(currently_stepping=%d)",
4951 paddress (target_gdbarch (),
4952 t
->suspend
.stop_pc
),
4953 target_pid_to_str (t
->ptid
).c_str (),
4954 currently_stepping (t
));
4964 stop_all_threads (const char *reason
, inferior
*inf
)
4966 /* We may need multiple passes to discover all threads. */
4970 gdb_assert (exists_non_stop_target ());
4972 INFRUN_SCOPED_DEBUG_START_END ("reason=%s, inf=%d", reason
,
4973 inf
!= nullptr ? inf
->num
: -1);
4975 scoped_restore_current_thread restore_thread
;
4977 /* Enable thread events on relevant targets. */
4978 for (auto *target
: all_non_exited_process_targets ())
4980 if (inf
!= nullptr && inf
->process_target () != target
)
4983 switch_to_target_no_thread (target
);
4984 target_thread_events (true);
4989 /* Disable thread events on relevant targets. */
4990 for (auto *target
: all_non_exited_process_targets ())
4992 if (inf
!= nullptr && inf
->process_target () != target
)
4995 switch_to_target_no_thread (target
);
4996 target_thread_events (false);
4999 /* Use debug_prefixed_printf directly to get a meaningful function
5002 debug_prefixed_printf ("infrun", "stop_all_threads", "done");
5005 /* Request threads to stop, and then wait for the stops. Because
5006 threads we already know about can spawn more threads while we're
5007 trying to stop them, and we only learn about new threads when we
5008 update the thread list, do this in a loop, and keep iterating
5009 until two passes find no threads that need to be stopped. */
5010 for (pass
= 0; pass
< 2; pass
++, iterations
++)
5012 infrun_debug_printf ("pass=%d, iterations=%d", pass
, iterations
);
5015 int waits_needed
= 0;
5017 for (auto *target
: all_non_exited_process_targets ())
5019 if (inf
!= nullptr && inf
->process_target () != target
)
5022 switch_to_target_no_thread (target
);
5023 update_thread_list ();
5026 /* Go through all threads looking for threads that we need
5027 to tell the target to stop. */
5028 for (thread_info
*t
: all_non_exited_threads ())
5030 if (inf
!= nullptr && t
->inf
!= inf
)
5033 /* For a single-target setting with an all-stop target,
5034 we would not even arrive here. For a multi-target
5035 setting, until GDB is able to handle a mixture of
5036 all-stop and non-stop targets, simply skip all-stop
5037 targets' threads. This should be fine due to the
5038 protection of 'check_multi_target_resumption'. */
5040 switch_to_thread_no_regs (t
);
5041 if (!target_is_non_stop_p ())
5046 /* If already stopping, don't request a stop again.
5047 We just haven't seen the notification yet. */
5048 if (!t
->stop_requested
)
5050 infrun_debug_printf (" %s executing, need stop",
5051 target_pid_to_str (t
->ptid
).c_str ());
5052 target_stop (t
->ptid
);
5053 t
->stop_requested
= 1;
5057 infrun_debug_printf (" %s executing, already stopping",
5058 target_pid_to_str (t
->ptid
).c_str ());
5061 if (t
->stop_requested
)
5066 infrun_debug_printf (" %s not executing",
5067 target_pid_to_str (t
->ptid
).c_str ());
5069 /* The thread may be not executing, but still be
5070 resumed with a pending status to process. */
5075 if (waits_needed
== 0)
5078 /* If we find new threads on the second iteration, restart
5079 over. We want to see two iterations in a row with all
5084 for (int i
= 0; i
< waits_needed
; i
++)
5086 wait_one_event event
= wait_one ();
5087 if (handle_one (event
))
5094 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
5097 handle_no_resumed (struct execution_control_state
*ecs
)
5099 if (target_can_async_p ())
5101 bool any_sync
= false;
5103 for (ui
*ui
: all_uis ())
5105 if (ui
->prompt_state
== PROMPT_BLOCKED
)
5113 /* There were no unwaited-for children left in the target, but,
5114 we're not synchronously waiting for events either. Just
5117 infrun_debug_printf ("TARGET_WAITKIND_NO_RESUMED (ignoring: bg)");
5118 prepare_to_wait (ecs
);
5123 /* Otherwise, if we were running a synchronous execution command, we
5124 may need to cancel it and give the user back the terminal.
5126 In non-stop mode, the target can't tell whether we've already
5127 consumed previous stop events, so it can end up sending us a
5128 no-resumed event like so:
5130 #0 - thread 1 is left stopped
5132 #1 - thread 2 is resumed and hits breakpoint
5133 -> TARGET_WAITKIND_STOPPED
5135 #2 - thread 3 is resumed and exits
5136 this is the last resumed thread, so
5137 -> TARGET_WAITKIND_NO_RESUMED
5139 #3 - gdb processes stop for thread 2 and decides to re-resume
5142 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
5143 thread 2 is now resumed, so the event should be ignored.
5145 IOW, if the stop for thread 2 doesn't end a foreground command,
5146 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
5147 event. But it could be that the event meant that thread 2 itself
5148 (or whatever other thread was the last resumed thread) exited.
5150 To address this we refresh the thread list and check whether we
5151 have resumed threads _now_. In the example above, this removes
5152 thread 3 from the thread list. If thread 2 was re-resumed, we
5153 ignore this event. If we find no thread resumed, then we cancel
5154 the synchronous command and show "no unwaited-for " to the
5157 inferior
*curr_inf
= current_inferior ();
5159 scoped_restore_current_thread restore_thread
;
5161 for (auto *target
: all_non_exited_process_targets ())
5163 switch_to_target_no_thread (target
);
5164 update_thread_list ();
5169 - the current target has no thread executing, and
5170 - the current inferior is native, and
5171 - the current inferior is the one which has the terminal, and
5174 then a Ctrl-C from this point on would remain stuck in the
5175 kernel, until a thread resumes and dequeues it. That would
5176 result in the GDB CLI not reacting to Ctrl-C, not able to
5177 interrupt the program. To address this, if the current inferior
5178 no longer has any thread executing, we give the terminal to some
5179 other inferior that has at least one thread executing. */
5180 bool swap_terminal
= true;
5182 /* Whether to ignore this TARGET_WAITKIND_NO_RESUMED event, or
5183 whether to report it to the user. */
5184 bool ignore_event
= false;
5186 for (thread_info
*thread
: all_non_exited_threads ())
5188 if (swap_terminal
&& thread
->executing
)
5190 if (thread
->inf
!= curr_inf
)
5192 target_terminal::ours ();
5194 switch_to_thread (thread
);
5195 target_terminal::inferior ();
5197 swap_terminal
= false;
5201 && (thread
->executing
5202 || thread
->suspend
.waitstatus_pending_p
))
5204 /* Either there were no unwaited-for children left in the
5205 target at some point, but there are now, or some target
5206 other than the eventing one has unwaited-for children
5207 left. Just ignore. */
5208 infrun_debug_printf ("TARGET_WAITKIND_NO_RESUMED "
5209 "(ignoring: found resumed)");
5211 ignore_event
= true;
5214 if (ignore_event
&& !swap_terminal
)
5220 switch_to_inferior_no_thread (curr_inf
);
5221 prepare_to_wait (ecs
);
5225 /* Go ahead and report the event. */
5229 /* Given an execution control state that has been freshly filled in by
5230 an event from the inferior, figure out what it means and take
5233 The alternatives are:
5235 1) stop_waiting and return; to really stop and return to the
5238 2) keep_going and return; to wait for the next event (set
5239 ecs->event_thread->stepping_over_breakpoint to 1 to single step
5243 handle_inferior_event (struct execution_control_state
*ecs
)
5245 /* Make sure that all temporary struct value objects that were
5246 created during the handling of the event get deleted at the
5248 scoped_value_mark free_values
;
5250 infrun_debug_printf ("%s", target_waitstatus_to_string (&ecs
->ws
).c_str ());
5252 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
5254 /* We had an event in the inferior, but we are not interested in
5255 handling it at this level. The lower layers have already
5256 done what needs to be done, if anything.
5258 One of the possible circumstances for this is when the
5259 inferior produces output for the console. The inferior has
5260 not stopped, and we are ignoring the event. Another possible
5261 circumstance is any event which the lower level knows will be
5262 reported multiple times without an intervening resume. */
5263 prepare_to_wait (ecs
);
5267 if (ecs
->ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
)
5269 prepare_to_wait (ecs
);
5273 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
5274 && handle_no_resumed (ecs
))
5277 /* Cache the last target/ptid/waitstatus. */
5278 set_last_target_status (ecs
->target
, ecs
->ptid
, ecs
->ws
);
5280 /* Always clear state belonging to the previous time we stopped. */
5281 stop_stack_dummy
= STOP_NONE
;
5283 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
5285 /* No unwaited-for children left. IOW, all resumed children
5287 stop_print_frame
= false;
5292 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
5293 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
5295 ecs
->event_thread
= find_thread_ptid (ecs
->target
, ecs
->ptid
);
5296 /* If it's a new thread, add it to the thread database. */
5297 if (ecs
->event_thread
== NULL
)
5298 ecs
->event_thread
= add_thread (ecs
->target
, ecs
->ptid
);
5300 /* Disable range stepping. If the next step request could use a
5301 range, this will be end up re-enabled then. */
5302 ecs
->event_thread
->control
.may_range_step
= 0;
5305 /* Dependent on valid ECS->EVENT_THREAD. */
5306 adjust_pc_after_break (ecs
->event_thread
, &ecs
->ws
);
5308 /* Dependent on the current PC value modified by adjust_pc_after_break. */
5309 reinit_frame_cache ();
5311 breakpoint_retire_moribund ();
5313 /* First, distinguish signals caused by the debugger from signals
5314 that have to do with the program's own actions. Note that
5315 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
5316 on the operating system version. Here we detect when a SIGILL or
5317 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
5318 something similar for SIGSEGV, since a SIGSEGV will be generated
5319 when we're trying to execute a breakpoint instruction on a
5320 non-executable stack. This happens for call dummy breakpoints
5321 for architectures like SPARC that place call dummies on the
5323 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
5324 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
5325 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
5326 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
5328 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
5330 if (breakpoint_inserted_here_p (regcache
->aspace (),
5331 regcache_read_pc (regcache
)))
5333 infrun_debug_printf ("Treating signal as SIGTRAP");
5334 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
5338 mark_non_executing_threads (ecs
->target
, ecs
->ptid
, ecs
->ws
);
5340 switch (ecs
->ws
.kind
)
5342 case TARGET_WAITKIND_LOADED
:
5344 context_switch (ecs
);
5345 /* Ignore gracefully during startup of the inferior, as it might
5346 be the shell which has just loaded some objects, otherwise
5347 add the symbols for the newly loaded objects. Also ignore at
5348 the beginning of an attach or remote session; we will query
5349 the full list of libraries once the connection is
5352 stop_kind stop_soon
= get_inferior_stop_soon (ecs
);
5353 if (stop_soon
== NO_STOP_QUIETLY
)
5355 struct regcache
*regcache
;
5357 regcache
= get_thread_regcache (ecs
->event_thread
);
5359 handle_solib_event ();
5361 ecs
->event_thread
->control
.stop_bpstat
5362 = bpstat_stop_status (regcache
->aspace (),
5363 ecs
->event_thread
->suspend
.stop_pc
,
5364 ecs
->event_thread
, &ecs
->ws
);
5366 if (handle_stop_requested (ecs
))
5369 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5371 /* A catchpoint triggered. */
5372 process_event_stop_test (ecs
);
5376 /* If requested, stop when the dynamic linker notifies
5377 gdb of events. This allows the user to get control
5378 and place breakpoints in initializer routines for
5379 dynamically loaded objects (among other things). */
5380 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5381 if (stop_on_solib_events
)
5383 /* Make sure we print "Stopped due to solib-event" in
5385 stop_print_frame
= true;
5392 /* If we are skipping through a shell, or through shared library
5393 loading that we aren't interested in, resume the program. If
5394 we're running the program normally, also resume. */
5395 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
5397 /* Loading of shared libraries might have changed breakpoint
5398 addresses. Make sure new breakpoints are inserted. */
5399 if (stop_soon
== NO_STOP_QUIETLY
)
5400 insert_breakpoints ();
5401 resume (GDB_SIGNAL_0
);
5402 prepare_to_wait (ecs
);
5406 /* But stop if we're attaching or setting up a remote
5408 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5409 || stop_soon
== STOP_QUIETLY_REMOTE
)
5411 infrun_debug_printf ("quietly stopped");
5416 internal_error (__FILE__
, __LINE__
,
5417 _("unhandled stop_soon: %d"), (int) stop_soon
);
5420 case TARGET_WAITKIND_SPURIOUS
:
5421 if (handle_stop_requested (ecs
))
5423 context_switch (ecs
);
5424 resume (GDB_SIGNAL_0
);
5425 prepare_to_wait (ecs
);
5428 case TARGET_WAITKIND_THREAD_CREATED
:
5429 if (handle_stop_requested (ecs
))
5431 context_switch (ecs
);
5432 if (!switch_back_to_stepped_thread (ecs
))
5436 case TARGET_WAITKIND_EXITED
:
5437 case TARGET_WAITKIND_SIGNALLED
:
5439 /* Depending on the system, ecs->ptid may point to a thread or
5440 to a process. On some targets, target_mourn_inferior may
5441 need to have access to the just-exited thread. That is the
5442 case of GNU/Linux's "checkpoint" support, for example.
5443 Call the switch_to_xxx routine as appropriate. */
5444 thread_info
*thr
= find_thread_ptid (ecs
->target
, ecs
->ptid
);
5446 switch_to_thread (thr
);
5449 inferior
*inf
= find_inferior_ptid (ecs
->target
, ecs
->ptid
);
5450 switch_to_inferior_no_thread (inf
);
5453 handle_vfork_child_exec_or_exit (0);
5454 target_terminal::ours (); /* Must do this before mourn anyway. */
5456 /* Clearing any previous state of convenience variables. */
5457 clear_exit_convenience_vars ();
5459 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5461 /* Record the exit code in the convenience variable $_exitcode, so
5462 that the user can inspect this again later. */
5463 set_internalvar_integer (lookup_internalvar ("_exitcode"),
5464 (LONGEST
) ecs
->ws
.value
.integer
);
5466 /* Also record this in the inferior itself. */
5467 current_inferior ()->has_exit_code
= 1;
5468 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
5470 /* Support the --return-child-result option. */
5471 return_child_result_value
= ecs
->ws
.value
.integer
;
5473 gdb::observers::exited
.notify (ecs
->ws
.value
.integer
);
5477 struct gdbarch
*gdbarch
= current_inferior ()->gdbarch
;
5479 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
5481 /* Set the value of the internal variable $_exitsignal,
5482 which holds the signal uncaught by the inferior. */
5483 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
5484 gdbarch_gdb_signal_to_target (gdbarch
,
5485 ecs
->ws
.value
.sig
));
5489 /* We don't have access to the target's method used for
5490 converting between signal numbers (GDB's internal
5491 representation <-> target's representation).
5492 Therefore, we cannot do a good job at displaying this
5493 information to the user. It's better to just warn
5494 her about it (if infrun debugging is enabled), and
5496 infrun_debug_printf ("Cannot fill $_exitsignal with the correct "
5500 gdb::observers::signal_exited
.notify (ecs
->ws
.value
.sig
);
5503 gdb_flush (gdb_stdout
);
5504 target_mourn_inferior (inferior_ptid
);
5505 stop_print_frame
= false;
5509 case TARGET_WAITKIND_FORKED
:
5510 case TARGET_WAITKIND_VFORKED
:
5511 /* Check whether the inferior is displaced stepping. */
5513 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
5514 struct gdbarch
*gdbarch
= regcache
->arch ();
5515 inferior
*parent_inf
= find_inferior_ptid (ecs
->target
, ecs
->ptid
);
5517 /* If this is a fork (child gets its own address space copy)
5518 and some displaced step buffers were in use at the time of
5519 the fork, restore the displaced step buffer bytes in the
5522 Architectures which support displaced stepping and fork
5523 events must supply an implementation of
5524 gdbarch_displaced_step_restore_all_in_ptid. This is not
5525 enforced during gdbarch validation to support architectures
5526 which support displaced stepping but not forks. */
5527 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
5528 && gdbarch_supports_displaced_stepping (gdbarch
))
5529 gdbarch_displaced_step_restore_all_in_ptid
5530 (gdbarch
, parent_inf
, ecs
->ws
.value
.related_pid
);
5532 /* If displaced stepping is supported, and thread ecs->ptid is
5533 displaced stepping. */
5534 if (displaced_step_in_progress_thread (ecs
->event_thread
))
5536 struct regcache
*child_regcache
;
5537 CORE_ADDR parent_pc
;
5539 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
5540 indicating that the displaced stepping of syscall instruction
5541 has been done. Perform cleanup for parent process here. Note
5542 that this operation also cleans up the child process for vfork,
5543 because their pages are shared. */
5544 displaced_step_finish (ecs
->event_thread
, GDB_SIGNAL_TRAP
);
5545 /* Start a new step-over in another thread if there's one
5549 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
5550 the child's PC is also within the scratchpad. Set the child's PC
5551 to the parent's PC value, which has already been fixed up.
5552 FIXME: we use the parent's aspace here, although we're touching
5553 the child, because the child hasn't been added to the inferior
5554 list yet at this point. */
5557 = get_thread_arch_aspace_regcache (parent_inf
->process_target (),
5558 ecs
->ws
.value
.related_pid
,
5560 parent_inf
->aspace
);
5561 /* Read PC value of parent process. */
5562 parent_pc
= regcache_read_pc (regcache
);
5564 displaced_debug_printf ("write child pc from %s to %s",
5566 regcache_read_pc (child_regcache
)),
5567 paddress (gdbarch
, parent_pc
));
5569 regcache_write_pc (child_regcache
, parent_pc
);
5573 context_switch (ecs
);
5575 /* Immediately detach breakpoints from the child before there's
5576 any chance of letting the user delete breakpoints from the
5577 breakpoint lists. If we don't do this early, it's easy to
5578 leave left over traps in the child, vis: "break foo; catch
5579 fork; c; <fork>; del; c; <child calls foo>". We only follow
5580 the fork on the last `continue', and by that time the
5581 breakpoint at "foo" is long gone from the breakpoint table.
5582 If we vforked, then we don't need to unpatch here, since both
5583 parent and child are sharing the same memory pages; we'll
5584 need to unpatch at follow/detach time instead to be certain
5585 that new breakpoints added between catchpoint hit time and
5586 vfork follow are detached. */
5587 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
5589 /* This won't actually modify the breakpoint list, but will
5590 physically remove the breakpoints from the child. */
5591 detach_breakpoints (ecs
->ws
.value
.related_pid
);
5594 delete_just_stopped_threads_single_step_breakpoints ();
5596 /* In case the event is caught by a catchpoint, remember that
5597 the event is to be followed at the next resume of the thread,
5598 and not immediately. */
5599 ecs
->event_thread
->pending_follow
= ecs
->ws
;
5601 ecs
->event_thread
->suspend
.stop_pc
5602 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
5604 ecs
->event_thread
->control
.stop_bpstat
5605 = bpstat_stop_status (get_current_regcache ()->aspace (),
5606 ecs
->event_thread
->suspend
.stop_pc
,
5607 ecs
->event_thread
, &ecs
->ws
);
5609 if (handle_stop_requested (ecs
))
5612 /* If no catchpoint triggered for this, then keep going. Note
5613 that we're interested in knowing the bpstat actually causes a
5614 stop, not just if it may explain the signal. Software
5615 watchpoints, for example, always appear in the bpstat. */
5616 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5619 = (follow_fork_mode_string
== follow_fork_mode_child
);
5621 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5623 process_stratum_target
*targ
5624 = ecs
->event_thread
->inf
->process_target ();
5626 bool should_resume
= follow_fork ();
5628 /* Note that one of these may be an invalid pointer,
5629 depending on detach_fork. */
5630 thread_info
*parent
= ecs
->event_thread
;
5632 = find_thread_ptid (targ
, ecs
->ws
.value
.related_pid
);
5634 /* At this point, the parent is marked running, and the
5635 child is marked stopped. */
5637 /* If not resuming the parent, mark it stopped. */
5638 if (follow_child
&& !detach_fork
&& !non_stop
&& !sched_multi
)
5639 parent
->set_running (false);
5641 /* If resuming the child, mark it running. */
5642 if (follow_child
|| (!detach_fork
&& (non_stop
|| sched_multi
)))
5643 child
->set_running (true);
5645 /* In non-stop mode, also resume the other branch. */
5646 if (!detach_fork
&& (non_stop
5647 || (sched_multi
&& target_is_non_stop_p ())))
5650 switch_to_thread (parent
);
5652 switch_to_thread (child
);
5654 ecs
->event_thread
= inferior_thread ();
5655 ecs
->ptid
= inferior_ptid
;
5660 switch_to_thread (child
);
5662 switch_to_thread (parent
);
5664 ecs
->event_thread
= inferior_thread ();
5665 ecs
->ptid
= inferior_ptid
;
5673 process_event_stop_test (ecs
);
5676 case TARGET_WAITKIND_VFORK_DONE
:
5677 /* Done with the shared memory region. Re-insert breakpoints in
5678 the parent, and keep going. */
5680 context_switch (ecs
);
5682 current_inferior ()->thread_waiting_for_vfork_done
= nullptr;
5683 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
5685 if (handle_stop_requested (ecs
))
5688 /* This also takes care of reinserting breakpoints in the
5689 previously locked inferior. */
5693 case TARGET_WAITKIND_EXECD
:
5695 /* Note we can't read registers yet (the stop_pc), because we
5696 don't yet know the inferior's post-exec architecture.
5697 'stop_pc' is explicitly read below instead. */
5698 switch_to_thread_no_regs (ecs
->event_thread
);
5700 /* Do whatever is necessary to the parent branch of the vfork. */
5701 handle_vfork_child_exec_or_exit (1);
5703 /* This causes the eventpoints and symbol table to be reset.
5704 Must do this now, before trying to determine whether to
5706 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
5708 /* In follow_exec we may have deleted the original thread and
5709 created a new one. Make sure that the event thread is the
5710 execd thread for that case (this is a nop otherwise). */
5711 ecs
->event_thread
= inferior_thread ();
5713 ecs
->event_thread
->suspend
.stop_pc
5714 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
5716 ecs
->event_thread
->control
.stop_bpstat
5717 = bpstat_stop_status (get_current_regcache ()->aspace (),
5718 ecs
->event_thread
->suspend
.stop_pc
,
5719 ecs
->event_thread
, &ecs
->ws
);
5721 /* Note that this may be referenced from inside
5722 bpstat_stop_status above, through inferior_has_execd. */
5723 xfree (ecs
->ws
.value
.execd_pathname
);
5724 ecs
->ws
.value
.execd_pathname
= NULL
;
5726 if (handle_stop_requested (ecs
))
5729 /* If no catchpoint triggered for this, then keep going. */
5730 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5732 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5736 process_event_stop_test (ecs
);
5739 /* Be careful not to try to gather much state about a thread
5740 that's in a syscall. It's frequently a losing proposition. */
5741 case TARGET_WAITKIND_SYSCALL_ENTRY
:
5742 /* Getting the current syscall number. */
5743 if (handle_syscall_event (ecs
) == 0)
5744 process_event_stop_test (ecs
);
5747 /* Before examining the threads further, step this thread to
5748 get it entirely out of the syscall. (We get notice of the
5749 event when the thread is just on the verge of exiting a
5750 syscall. Stepping one instruction seems to get it back
5752 case TARGET_WAITKIND_SYSCALL_RETURN
:
5753 if (handle_syscall_event (ecs
) == 0)
5754 process_event_stop_test (ecs
);
5757 case TARGET_WAITKIND_STOPPED
:
5758 handle_signal_stop (ecs
);
5761 case TARGET_WAITKIND_NO_HISTORY
:
5762 /* Reverse execution: target ran out of history info. */
5764 /* Switch to the stopped thread. */
5765 context_switch (ecs
);
5766 infrun_debug_printf ("stopped");
5768 delete_just_stopped_threads_single_step_breakpoints ();
5769 ecs
->event_thread
->suspend
.stop_pc
5770 = regcache_read_pc (get_thread_regcache (inferior_thread ()));
5772 if (handle_stop_requested (ecs
))
5775 gdb::observers::no_history
.notify ();
5781 /* Restart threads back to what they were trying to do back when we
5782 paused them (because of an in-line step-over or vfork, for example).
5783 The EVENT_THREAD thread is ignored (not restarted).
5785 If INF is non-nullptr, only resume threads from INF. */
5788 restart_threads (struct thread_info
*event_thread
, inferior
*inf
)
5790 INFRUN_SCOPED_DEBUG_START_END ("event_thread=%s, inf=%d",
5791 event_thread
->ptid
.to_string ().c_str (),
5792 inf
!= nullptr ? inf
->num
: -1);
5794 /* In case the instruction just stepped spawned a new thread. */
5795 update_thread_list ();
5797 for (thread_info
*tp
: all_non_exited_threads ())
5799 if (inf
!= nullptr && tp
->inf
!= inf
)
5802 if (tp
->inf
->detaching
)
5804 infrun_debug_printf ("restart threads: [%s] inferior detaching",
5805 target_pid_to_str (tp
->ptid
).c_str ());
5809 switch_to_thread_no_regs (tp
);
5811 if (tp
== event_thread
)
5813 infrun_debug_printf ("restart threads: [%s] is event thread",
5814 target_pid_to_str (tp
->ptid
).c_str ());
5818 if (!(tp
->state
== THREAD_RUNNING
|| tp
->control
.in_infcall
))
5820 infrun_debug_printf ("restart threads: [%s] not meant to be running",
5821 target_pid_to_str (tp
->ptid
).c_str ());
5827 infrun_debug_printf ("restart threads: [%s] resumed",
5828 target_pid_to_str (tp
->ptid
).c_str ());
5829 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
5833 if (thread_is_in_step_over_chain (tp
))
5835 infrun_debug_printf ("restart threads: [%s] needs step-over",
5836 target_pid_to_str (tp
->ptid
).c_str ());
5837 gdb_assert (!tp
->resumed
);
5842 if (tp
->suspend
.waitstatus_pending_p
)
5844 infrun_debug_printf ("restart threads: [%s] has pending status",
5845 target_pid_to_str (tp
->ptid
).c_str ());
5850 gdb_assert (!tp
->stop_requested
);
5852 /* If some thread needs to start a step-over at this point, it
5853 should still be in the step-over queue, and thus skipped
5855 if (thread_still_needs_step_over (tp
))
5857 internal_error (__FILE__
, __LINE__
,
5858 "thread [%s] needs a step-over, but not in "
5859 "step-over queue\n",
5860 target_pid_to_str (tp
->ptid
).c_str ());
5863 if (currently_stepping (tp
))
5865 infrun_debug_printf ("restart threads: [%s] was stepping",
5866 target_pid_to_str (tp
->ptid
).c_str ());
5867 keep_going_stepped_thread (tp
);
5871 struct execution_control_state ecss
;
5872 struct execution_control_state
*ecs
= &ecss
;
5874 infrun_debug_printf ("restart threads: [%s] continuing",
5875 target_pid_to_str (tp
->ptid
).c_str ());
5876 reset_ecs (ecs
, tp
);
5877 switch_to_thread (tp
);
5878 keep_going_pass_signal (ecs
);
5883 /* Callback for iterate_over_threads. Find a resumed thread that has
5884 a pending waitstatus. */
5887 resumed_thread_with_pending_status (struct thread_info
*tp
,
5891 && tp
->suspend
.waitstatus_pending_p
);
5894 /* Called when we get an event that may finish an in-line or
5895 out-of-line (displaced stepping) step-over started previously.
5896 Return true if the event is processed and we should go back to the
5897 event loop; false if the caller should continue processing the
5901 finish_step_over (struct execution_control_state
*ecs
)
5903 displaced_step_finish (ecs
->event_thread
,
5904 ecs
->event_thread
->suspend
.stop_signal
);
5906 bool had_step_over_info
= step_over_info_valid_p ();
5908 if (had_step_over_info
)
5910 /* If we're stepping over a breakpoint with all threads locked,
5911 then only the thread that was stepped should be reporting
5913 gdb_assert (ecs
->event_thread
->control
.trap_expected
);
5915 clear_step_over_info ();
5918 if (!target_is_non_stop_p ())
5921 /* Start a new step-over in another thread if there's one that
5925 /* If we were stepping over a breakpoint before, and haven't started
5926 a new in-line step-over sequence, then restart all other threads
5927 (except the event thread). We can't do this in all-stop, as then
5928 e.g., we wouldn't be able to issue any other remote packet until
5929 these other threads stop. */
5930 if (had_step_over_info
&& !step_over_info_valid_p ())
5932 struct thread_info
*pending
;
5934 /* If we only have threads with pending statuses, the restart
5935 below won't restart any thread and so nothing re-inserts the
5936 breakpoint we just stepped over. But we need it inserted
5937 when we later process the pending events, otherwise if
5938 another thread has a pending event for this breakpoint too,
5939 we'd discard its event (because the breakpoint that
5940 originally caused the event was no longer inserted). */
5941 context_switch (ecs
);
5942 insert_breakpoints ();
5944 restart_threads (ecs
->event_thread
);
5946 /* If we have events pending, go through handle_inferior_event
5947 again, picking up a pending event at random. This avoids
5948 thread starvation. */
5950 /* But not if we just stepped over a watchpoint in order to let
5951 the instruction execute so we can evaluate its expression.
5952 The set of watchpoints that triggered is recorded in the
5953 breakpoint objects themselves (see bp->watchpoint_triggered).
5954 If we processed another event first, that other event could
5955 clobber this info. */
5956 if (ecs
->event_thread
->stepping_over_watchpoint
)
5959 pending
= iterate_over_threads (resumed_thread_with_pending_status
,
5961 if (pending
!= NULL
)
5963 struct thread_info
*tp
= ecs
->event_thread
;
5964 struct regcache
*regcache
;
5966 infrun_debug_printf ("found resumed threads with "
5967 "pending events, saving status");
5969 gdb_assert (pending
!= tp
);
5971 /* Record the event thread's event for later. */
5972 save_waitstatus (tp
, &ecs
->ws
);
5973 /* This was cleared early, by handle_inferior_event. Set it
5974 so this pending event is considered by
5978 gdb_assert (!tp
->executing
);
5980 regcache
= get_thread_regcache (tp
);
5981 tp
->suspend
.stop_pc
= regcache_read_pc (regcache
);
5983 infrun_debug_printf ("saved stop_pc=%s for %s "
5984 "(currently_stepping=%d)",
5985 paddress (target_gdbarch (),
5986 tp
->suspend
.stop_pc
),
5987 target_pid_to_str (tp
->ptid
).c_str (),
5988 currently_stepping (tp
));
5990 /* This in-line step-over finished; clear this so we won't
5991 start a new one. This is what handle_signal_stop would
5992 do, if we returned false. */
5993 tp
->stepping_over_breakpoint
= 0;
5995 /* Wake up the event loop again. */
5996 mark_async_event_handler (infrun_async_inferior_event_token
);
5998 prepare_to_wait (ecs
);
6006 /* Come here when the program has stopped with a signal. */
6009 handle_signal_stop (struct execution_control_state
*ecs
)
6011 struct frame_info
*frame
;
6012 struct gdbarch
*gdbarch
;
6013 int stopped_by_watchpoint
;
6014 enum stop_kind stop_soon
;
6017 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
6019 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
6021 /* Do we need to clean up the state of a thread that has
6022 completed a displaced single-step? (Doing so usually affects
6023 the PC, so do it here, before we set stop_pc.) */
6024 if (finish_step_over (ecs
))
6027 /* If we either finished a single-step or hit a breakpoint, but
6028 the user wanted this thread to be stopped, pretend we got a
6029 SIG0 (generic unsignaled stop). */
6030 if (ecs
->event_thread
->stop_requested
6031 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
6032 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6034 ecs
->event_thread
->suspend
.stop_pc
6035 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
6037 context_switch (ecs
);
6039 if (deprecated_context_hook
)
6040 deprecated_context_hook (ecs
->event_thread
->global_num
);
6044 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
6045 struct gdbarch
*reg_gdbarch
= regcache
->arch ();
6047 infrun_debug_printf ("stop_pc=%s",
6048 paddress (reg_gdbarch
,
6049 ecs
->event_thread
->suspend
.stop_pc
));
6050 if (target_stopped_by_watchpoint ())
6054 infrun_debug_printf ("stopped by watchpoint");
6056 if (target_stopped_data_address (current_inferior ()->top_target (),
6058 infrun_debug_printf ("stopped data address=%s",
6059 paddress (reg_gdbarch
, addr
));
6061 infrun_debug_printf ("(no data address available)");
6065 /* This is originated from start_remote(), start_inferior() and
6066 shared libraries hook functions. */
6067 stop_soon
= get_inferior_stop_soon (ecs
);
6068 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
6070 infrun_debug_printf ("quietly stopped");
6071 stop_print_frame
= true;
6076 /* This originates from attach_command(). We need to overwrite
6077 the stop_signal here, because some kernels don't ignore a
6078 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
6079 See more comments in inferior.h. On the other hand, if we
6080 get a non-SIGSTOP, report it to the user - assume the backend
6081 will handle the SIGSTOP if it should show up later.
6083 Also consider that the attach is complete when we see a
6084 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
6085 target extended-remote report it instead of a SIGSTOP
6086 (e.g. gdbserver). We already rely on SIGTRAP being our
6087 signal, so this is no exception.
6089 Also consider that the attach is complete when we see a
6090 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
6091 the target to stop all threads of the inferior, in case the
6092 low level attach operation doesn't stop them implicitly. If
6093 they weren't stopped implicitly, then the stub will report a
6094 GDB_SIGNAL_0, meaning: stopped for no particular reason
6095 other than GDB's request. */
6096 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
6097 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
6098 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6099 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
6101 stop_print_frame
= true;
6103 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6107 /* At this point, get hold of the now-current thread's frame. */
6108 frame
= get_current_frame ();
6109 gdbarch
= get_frame_arch (frame
);
6111 /* Pull the single step breakpoints out of the target. */
6112 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
6114 struct regcache
*regcache
;
6117 regcache
= get_thread_regcache (ecs
->event_thread
);
6118 const address_space
*aspace
= regcache
->aspace ();
6120 pc
= regcache_read_pc (regcache
);
6122 /* However, before doing so, if this single-step breakpoint was
6123 actually for another thread, set this thread up for moving
6125 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
6128 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
6130 infrun_debug_printf ("[%s] hit another thread's single-step "
6132 target_pid_to_str (ecs
->ptid
).c_str ());
6133 ecs
->hit_singlestep_breakpoint
= 1;
6138 infrun_debug_printf ("[%s] hit its single-step breakpoint",
6139 target_pid_to_str (ecs
->ptid
).c_str ());
6142 delete_just_stopped_threads_single_step_breakpoints ();
6144 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6145 && ecs
->event_thread
->control
.trap_expected
6146 && ecs
->event_thread
->stepping_over_watchpoint
)
6147 stopped_by_watchpoint
= 0;
6149 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
6151 /* If necessary, step over this watchpoint. We'll be back to display
6153 if (stopped_by_watchpoint
6154 && (target_have_steppable_watchpoint ()
6155 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
6157 /* At this point, we are stopped at an instruction which has
6158 attempted to write to a piece of memory under control of
6159 a watchpoint. The instruction hasn't actually executed
6160 yet. If we were to evaluate the watchpoint expression
6161 now, we would get the old value, and therefore no change
6162 would seem to have occurred.
6164 In order to make watchpoints work `right', we really need
6165 to complete the memory write, and then evaluate the
6166 watchpoint expression. We do this by single-stepping the
6169 It may not be necessary to disable the watchpoint to step over
6170 it. For example, the PA can (with some kernel cooperation)
6171 single step over a watchpoint without disabling the watchpoint.
6173 It is far more common to need to disable a watchpoint to step
6174 the inferior over it. If we have non-steppable watchpoints,
6175 we must disable the current watchpoint; it's simplest to
6176 disable all watchpoints.
6178 Any breakpoint at PC must also be stepped over -- if there's
6179 one, it will have already triggered before the watchpoint
6180 triggered, and we either already reported it to the user, or
6181 it didn't cause a stop and we called keep_going. In either
6182 case, if there was a breakpoint at PC, we must be trying to
6184 ecs
->event_thread
->stepping_over_watchpoint
= 1;
6189 ecs
->event_thread
->stepping_over_breakpoint
= 0;
6190 ecs
->event_thread
->stepping_over_watchpoint
= 0;
6191 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
6192 ecs
->event_thread
->control
.stop_step
= 0;
6193 stop_print_frame
= true;
6194 stopped_by_random_signal
= 0;
6195 bpstat stop_chain
= NULL
;
6197 /* Hide inlined functions starting here, unless we just performed stepi or
6198 nexti. After stepi and nexti, always show the innermost frame (not any
6199 inline function call sites). */
6200 if (ecs
->event_thread
->control
.step_range_end
!= 1)
6202 const address_space
*aspace
6203 = get_thread_regcache (ecs
->event_thread
)->aspace ();
6205 /* skip_inline_frames is expensive, so we avoid it if we can
6206 determine that the address is one where functions cannot have
6207 been inlined. This improves performance with inferiors that
6208 load a lot of shared libraries, because the solib event
6209 breakpoint is defined as the address of a function (i.e. not
6210 inline). Note that we have to check the previous PC as well
6211 as the current one to catch cases when we have just
6212 single-stepped off a breakpoint prior to reinstating it.
6213 Note that we're assuming that the code we single-step to is
6214 not inline, but that's not definitive: there's nothing
6215 preventing the event breakpoint function from containing
6216 inlined code, and the single-step ending up there. If the
6217 user had set a breakpoint on that inlined code, the missing
6218 skip_inline_frames call would break things. Fortunately
6219 that's an extremely unlikely scenario. */
6220 if (!pc_at_non_inline_function (aspace
,
6221 ecs
->event_thread
->suspend
.stop_pc
,
6223 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6224 && ecs
->event_thread
->control
.trap_expected
6225 && pc_at_non_inline_function (aspace
,
6226 ecs
->event_thread
->prev_pc
,
6229 stop_chain
= build_bpstat_chain (aspace
,
6230 ecs
->event_thread
->suspend
.stop_pc
,
6232 skip_inline_frames (ecs
->event_thread
, stop_chain
);
6234 /* Re-fetch current thread's frame in case that invalidated
6236 frame
= get_current_frame ();
6237 gdbarch
= get_frame_arch (frame
);
6241 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6242 && ecs
->event_thread
->control
.trap_expected
6243 && gdbarch_single_step_through_delay_p (gdbarch
)
6244 && currently_stepping (ecs
->event_thread
))
6246 /* We're trying to step off a breakpoint. Turns out that we're
6247 also on an instruction that needs to be stepped multiple
6248 times before it's been fully executing. E.g., architectures
6249 with a delay slot. It needs to be stepped twice, once for
6250 the instruction and once for the delay slot. */
6251 int step_through_delay
6252 = gdbarch_single_step_through_delay (gdbarch
, frame
);
6254 if (step_through_delay
)
6255 infrun_debug_printf ("step through delay");
6257 if (ecs
->event_thread
->control
.step_range_end
== 0
6258 && step_through_delay
)
6260 /* The user issued a continue when stopped at a breakpoint.
6261 Set up for another trap and get out of here. */
6262 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6266 else if (step_through_delay
)
6268 /* The user issued a step when stopped at a breakpoint.
6269 Maybe we should stop, maybe we should not - the delay
6270 slot *might* correspond to a line of source. In any
6271 case, don't decide that here, just set
6272 ecs->stepping_over_breakpoint, making sure we
6273 single-step again before breakpoints are re-inserted. */
6274 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6278 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
6279 handles this event. */
6280 ecs
->event_thread
->control
.stop_bpstat
6281 = bpstat_stop_status (get_current_regcache ()->aspace (),
6282 ecs
->event_thread
->suspend
.stop_pc
,
6283 ecs
->event_thread
, &ecs
->ws
, stop_chain
);
6285 /* Following in case break condition called a
6287 stop_print_frame
= true;
6289 /* This is where we handle "moribund" watchpoints. Unlike
6290 software breakpoints traps, hardware watchpoint traps are
6291 always distinguishable from random traps. If no high-level
6292 watchpoint is associated with the reported stop data address
6293 anymore, then the bpstat does not explain the signal ---
6294 simply make sure to ignore it if `stopped_by_watchpoint' is
6297 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6298 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
6300 && stopped_by_watchpoint
)
6302 infrun_debug_printf ("no user watchpoint explains watchpoint SIGTRAP, "
6306 /* NOTE: cagney/2003-03-29: These checks for a random signal
6307 at one stage in the past included checks for an inferior
6308 function call's call dummy's return breakpoint. The original
6309 comment, that went with the test, read:
6311 ``End of a stack dummy. Some systems (e.g. Sony news) give
6312 another signal besides SIGTRAP, so check here as well as
6315 If someone ever tries to get call dummys on a
6316 non-executable stack to work (where the target would stop
6317 with something like a SIGSEGV), then those tests might need
6318 to be re-instated. Given, however, that the tests were only
6319 enabled when momentary breakpoints were not being used, I
6320 suspect that it won't be the case.
6322 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
6323 be necessary for call dummies on a non-executable stack on
6326 /* See if the breakpoints module can explain the signal. */
6328 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
6329 ecs
->event_thread
->suspend
.stop_signal
);
6331 /* Maybe this was a trap for a software breakpoint that has since
6333 if (random_signal
&& target_stopped_by_sw_breakpoint ())
6335 if (gdbarch_program_breakpoint_here_p (gdbarch
,
6336 ecs
->event_thread
->suspend
.stop_pc
))
6338 struct regcache
*regcache
;
6341 /* Re-adjust PC to what the program would see if GDB was not
6343 regcache
= get_thread_regcache (ecs
->event_thread
);
6344 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
6347 gdb::optional
<scoped_restore_tmpl
<int>>
6348 restore_operation_disable
;
6350 if (record_full_is_used ())
6351 restore_operation_disable
.emplace
6352 (record_full_gdb_operation_disable_set ());
6354 regcache_write_pc (regcache
,
6355 ecs
->event_thread
->suspend
.stop_pc
+ decr_pc
);
6360 /* A delayed software breakpoint event. Ignore the trap. */
6361 infrun_debug_printf ("delayed software breakpoint trap, ignoring");
6366 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
6367 has since been removed. */
6368 if (random_signal
&& target_stopped_by_hw_breakpoint ())
6370 /* A delayed hardware breakpoint event. Ignore the trap. */
6371 infrun_debug_printf ("delayed hardware breakpoint/watchpoint "
6376 /* If not, perhaps stepping/nexting can. */
6378 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6379 && currently_stepping (ecs
->event_thread
));
6381 /* Perhaps the thread hit a single-step breakpoint of _another_
6382 thread. Single-step breakpoints are transparent to the
6383 breakpoints module. */
6385 random_signal
= !ecs
->hit_singlestep_breakpoint
;
6387 /* No? Perhaps we got a moribund watchpoint. */
6389 random_signal
= !stopped_by_watchpoint
;
6391 /* Always stop if the user explicitly requested this thread to
6393 if (ecs
->event_thread
->stop_requested
)
6396 infrun_debug_printf ("user-requested stop");
6399 /* For the program's own signals, act according to
6400 the signal handling tables. */
6404 /* Signal not for debugging purposes. */
6405 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
6407 infrun_debug_printf ("random signal (%s)",
6408 gdb_signal_to_symbol_string (stop_signal
));
6410 stopped_by_random_signal
= 1;
6412 /* Always stop on signals if we're either just gaining control
6413 of the program, or the user explicitly requested this thread
6414 to remain stopped. */
6415 if (stop_soon
!= NO_STOP_QUIETLY
6416 || ecs
->event_thread
->stop_requested
6417 || signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
))
6423 /* Notify observers the signal has "handle print" set. Note we
6424 returned early above if stopping; normal_stop handles the
6425 printing in that case. */
6426 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
6428 /* The signal table tells us to print about this signal. */
6429 target_terminal::ours_for_output ();
6430 gdb::observers::signal_received
.notify (ecs
->event_thread
->suspend
.stop_signal
);
6431 target_terminal::inferior ();
6434 /* Clear the signal if it should not be passed. */
6435 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
6436 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6438 if (ecs
->event_thread
->prev_pc
== ecs
->event_thread
->suspend
.stop_pc
6439 && ecs
->event_thread
->control
.trap_expected
6440 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6442 /* We were just starting a new sequence, attempting to
6443 single-step off of a breakpoint and expecting a SIGTRAP.
6444 Instead this signal arrives. This signal will take us out
6445 of the stepping range so GDB needs to remember to, when
6446 the signal handler returns, resume stepping off that
6448 /* To simplify things, "continue" is forced to use the same
6449 code paths as single-step - set a breakpoint at the
6450 signal return address and then, once hit, step off that
6452 infrun_debug_printf ("signal arrived while stepping over breakpoint");
6454 insert_hp_step_resume_breakpoint_at_frame (frame
);
6455 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6456 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6457 ecs
->event_thread
->control
.trap_expected
= 0;
6459 /* If we were nexting/stepping some other thread, switch to
6460 it, so that we don't continue it, losing control. */
6461 if (!switch_back_to_stepped_thread (ecs
))
6466 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
6467 && (pc_in_thread_step_range (ecs
->event_thread
->suspend
.stop_pc
,
6469 || ecs
->event_thread
->control
.step_range_end
== 1)
6470 && frame_id_eq (get_stack_frame_id (frame
),
6471 ecs
->event_thread
->control
.step_stack_frame_id
)
6472 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6474 /* The inferior is about to take a signal that will take it
6475 out of the single step range. Set a breakpoint at the
6476 current PC (which is presumably where the signal handler
6477 will eventually return) and then allow the inferior to
6480 Note that this is only needed for a signal delivered
6481 while in the single-step range. Nested signals aren't a
6482 problem as they eventually all return. */
6483 infrun_debug_printf ("signal may take us out of single-step range");
6485 clear_step_over_info ();
6486 insert_hp_step_resume_breakpoint_at_frame (frame
);
6487 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6488 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6489 ecs
->event_thread
->control
.trap_expected
= 0;
6494 /* Note: step_resume_breakpoint may be non-NULL. This occurs
6495 when either there's a nested signal, or when there's a
6496 pending signal enabled just as the signal handler returns
6497 (leaving the inferior at the step-resume-breakpoint without
6498 actually executing it). Either way continue until the
6499 breakpoint is really hit. */
6501 if (!switch_back_to_stepped_thread (ecs
))
6503 infrun_debug_printf ("random signal, keep going");
6510 process_event_stop_test (ecs
);
6513 /* Come here when we've got some debug event / signal we can explain
6514 (IOW, not a random signal), and test whether it should cause a
6515 stop, or whether we should resume the inferior (transparently).
6516 E.g., could be a breakpoint whose condition evaluates false; we
6517 could be still stepping within the line; etc. */
6520 process_event_stop_test (struct execution_control_state
*ecs
)
6522 struct symtab_and_line stop_pc_sal
;
6523 struct frame_info
*frame
;
6524 struct gdbarch
*gdbarch
;
6525 CORE_ADDR jmp_buf_pc
;
6526 struct bpstat_what what
;
6528 /* Handle cases caused by hitting a breakpoint. */
6530 frame
= get_current_frame ();
6531 gdbarch
= get_frame_arch (frame
);
6533 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
6535 if (what
.call_dummy
)
6537 stop_stack_dummy
= what
.call_dummy
;
6540 /* A few breakpoint types have callbacks associated (e.g.,
6541 bp_jit_event). Run them now. */
6542 bpstat_run_callbacks (ecs
->event_thread
->control
.stop_bpstat
);
6544 /* If we hit an internal event that triggers symbol changes, the
6545 current frame will be invalidated within bpstat_what (e.g., if we
6546 hit an internal solib event). Re-fetch it. */
6547 frame
= get_current_frame ();
6548 gdbarch
= get_frame_arch (frame
);
6550 switch (what
.main_action
)
6552 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
6553 /* If we hit the breakpoint at longjmp while stepping, we
6554 install a momentary breakpoint at the target of the
6557 infrun_debug_printf ("BPSTAT_WHAT_SET_LONGJMP_RESUME");
6559 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6561 if (what
.is_longjmp
)
6563 struct value
*arg_value
;
6565 /* If we set the longjmp breakpoint via a SystemTap probe,
6566 then use it to extract the arguments. The destination PC
6567 is the third argument to the probe. */
6568 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
6571 jmp_buf_pc
= value_as_address (arg_value
);
6572 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
6574 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
6575 || !gdbarch_get_longjmp_target (gdbarch
,
6576 frame
, &jmp_buf_pc
))
6578 infrun_debug_printf ("BPSTAT_WHAT_SET_LONGJMP_RESUME "
6579 "(!gdbarch_get_longjmp_target)");
6584 /* Insert a breakpoint at resume address. */
6585 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
6588 check_exception_resume (ecs
, frame
);
6592 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
6594 struct frame_info
*init_frame
;
6596 /* There are several cases to consider.
6598 1. The initiating frame no longer exists. In this case we
6599 must stop, because the exception or longjmp has gone too
6602 2. The initiating frame exists, and is the same as the
6603 current frame. We stop, because the exception or longjmp
6606 3. The initiating frame exists and is different from the
6607 current frame. This means the exception or longjmp has
6608 been caught beneath the initiating frame, so keep going.
6610 4. longjmp breakpoint has been placed just to protect
6611 against stale dummy frames and user is not interested in
6612 stopping around longjmps. */
6614 infrun_debug_printf ("BPSTAT_WHAT_CLEAR_LONGJMP_RESUME");
6616 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
6618 delete_exception_resume_breakpoint (ecs
->event_thread
);
6620 if (what
.is_longjmp
)
6622 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
6624 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
6632 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
6636 struct frame_id current_id
6637 = get_frame_id (get_current_frame ());
6638 if (frame_id_eq (current_id
,
6639 ecs
->event_thread
->initiating_frame
))
6641 /* Case 2. Fall through. */
6651 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6653 delete_step_resume_breakpoint (ecs
->event_thread
);
6655 end_stepping_range (ecs
);
6659 case BPSTAT_WHAT_SINGLE
:
6660 infrun_debug_printf ("BPSTAT_WHAT_SINGLE");
6661 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6662 /* Still need to check other stuff, at least the case where we
6663 are stepping and step out of the right range. */
6666 case BPSTAT_WHAT_STEP_RESUME
:
6667 infrun_debug_printf ("BPSTAT_WHAT_STEP_RESUME");
6669 delete_step_resume_breakpoint (ecs
->event_thread
);
6670 if (ecs
->event_thread
->control
.proceed_to_finish
6671 && execution_direction
== EXEC_REVERSE
)
6673 struct thread_info
*tp
= ecs
->event_thread
;
6675 /* We are finishing a function in reverse, and just hit the
6676 step-resume breakpoint at the start address of the
6677 function, and we're almost there -- just need to back up
6678 by one more single-step, which should take us back to the
6680 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
6684 fill_in_stop_func (gdbarch
, ecs
);
6685 if (ecs
->event_thread
->suspend
.stop_pc
== ecs
->stop_func_start
6686 && execution_direction
== EXEC_REVERSE
)
6688 /* We are stepping over a function call in reverse, and just
6689 hit the step-resume breakpoint at the start address of
6690 the function. Go back to single-stepping, which should
6691 take us back to the function call. */
6692 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6698 case BPSTAT_WHAT_STOP_NOISY
:
6699 infrun_debug_printf ("BPSTAT_WHAT_STOP_NOISY");
6700 stop_print_frame
= true;
6702 /* Assume the thread stopped for a breakpoint. We'll still check
6703 whether a/the breakpoint is there when the thread is next
6705 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6710 case BPSTAT_WHAT_STOP_SILENT
:
6711 infrun_debug_printf ("BPSTAT_WHAT_STOP_SILENT");
6712 stop_print_frame
= false;
6714 /* Assume the thread stopped for a breakpoint. We'll still check
6715 whether a/the breakpoint is there when the thread is next
6717 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6721 case BPSTAT_WHAT_HP_STEP_RESUME
:
6722 infrun_debug_printf ("BPSTAT_WHAT_HP_STEP_RESUME");
6724 delete_step_resume_breakpoint (ecs
->event_thread
);
6725 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
6727 /* Back when the step-resume breakpoint was inserted, we
6728 were trying to single-step off a breakpoint. Go back to
6730 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6731 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6737 case BPSTAT_WHAT_KEEP_CHECKING
:
6741 /* If we stepped a permanent breakpoint and we had a high priority
6742 step-resume breakpoint for the address we stepped, but we didn't
6743 hit it, then we must have stepped into the signal handler. The
6744 step-resume was only necessary to catch the case of _not_
6745 stepping into the handler, so delete it, and fall through to
6746 checking whether the step finished. */
6747 if (ecs
->event_thread
->stepped_breakpoint
)
6749 struct breakpoint
*sr_bp
6750 = ecs
->event_thread
->control
.step_resume_breakpoint
;
6753 && sr_bp
->loc
->permanent
6754 && sr_bp
->type
== bp_hp_step_resume
6755 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
6757 infrun_debug_printf ("stepped permanent breakpoint, stopped in handler");
6758 delete_step_resume_breakpoint (ecs
->event_thread
);
6759 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6763 /* We come here if we hit a breakpoint but should not stop for it.
6764 Possibly we also were stepping and should stop for that. So fall
6765 through and test for stepping. But, if not stepping, do not
6768 /* In all-stop mode, if we're currently stepping but have stopped in
6769 some other thread, we need to switch back to the stepped thread. */
6770 if (switch_back_to_stepped_thread (ecs
))
6773 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
6775 infrun_debug_printf ("step-resume breakpoint is inserted");
6777 /* Having a step-resume breakpoint overrides anything
6778 else having to do with stepping commands until
6779 that breakpoint is reached. */
6784 if (ecs
->event_thread
->control
.step_range_end
== 0)
6786 infrun_debug_printf ("no stepping, continue");
6787 /* Likewise if we aren't even stepping. */
6792 /* Re-fetch current thread's frame in case the code above caused
6793 the frame cache to be re-initialized, making our FRAME variable
6794 a dangling pointer. */
6795 frame
= get_current_frame ();
6796 gdbarch
= get_frame_arch (frame
);
6797 fill_in_stop_func (gdbarch
, ecs
);
6799 /* If stepping through a line, keep going if still within it.
6801 Note that step_range_end is the address of the first instruction
6802 beyond the step range, and NOT the address of the last instruction
6805 Note also that during reverse execution, we may be stepping
6806 through a function epilogue and therefore must detect when
6807 the current-frame changes in the middle of a line. */
6809 if (pc_in_thread_step_range (ecs
->event_thread
->suspend
.stop_pc
,
6811 && (execution_direction
!= EXEC_REVERSE
6812 || frame_id_eq (get_frame_id (frame
),
6813 ecs
->event_thread
->control
.step_frame_id
)))
6816 ("stepping inside range [%s-%s]",
6817 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
6818 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
6820 /* Tentatively re-enable range stepping; `resume' disables it if
6821 necessary (e.g., if we're stepping over a breakpoint or we
6822 have software watchpoints). */
6823 ecs
->event_thread
->control
.may_range_step
= 1;
6825 /* When stepping backward, stop at beginning of line range
6826 (unless it's the function entry point, in which case
6827 keep going back to the call point). */
6828 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6829 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
6830 && stop_pc
!= ecs
->stop_func_start
6831 && execution_direction
== EXEC_REVERSE
)
6832 end_stepping_range (ecs
);
6839 /* We stepped out of the stepping range. */
6841 /* If we are stepping at the source level and entered the runtime
6842 loader dynamic symbol resolution code...
6844 EXEC_FORWARD: we keep on single stepping until we exit the run
6845 time loader code and reach the callee's address.
6847 EXEC_REVERSE: we've already executed the callee (backward), and
6848 the runtime loader code is handled just like any other
6849 undebuggable function call. Now we need only keep stepping
6850 backward through the trampoline code, and that's handled further
6851 down, so there is nothing for us to do here. */
6853 if (execution_direction
!= EXEC_REVERSE
6854 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6855 && in_solib_dynsym_resolve_code (ecs
->event_thread
->suspend
.stop_pc
))
6857 CORE_ADDR pc_after_resolver
=
6858 gdbarch_skip_solib_resolver (gdbarch
,
6859 ecs
->event_thread
->suspend
.stop_pc
);
6861 infrun_debug_printf ("stepped into dynsym resolve code");
6863 if (pc_after_resolver
)
6865 /* Set up a step-resume breakpoint at the address
6866 indicated by SKIP_SOLIB_RESOLVER. */
6867 symtab_and_line sr_sal
;
6868 sr_sal
.pc
= pc_after_resolver
;
6869 sr_sal
.pspace
= get_frame_program_space (frame
);
6871 insert_step_resume_breakpoint_at_sal (gdbarch
,
6872 sr_sal
, null_frame_id
);
6879 /* Step through an indirect branch thunk. */
6880 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6881 && gdbarch_in_indirect_branch_thunk (gdbarch
,
6882 ecs
->event_thread
->suspend
.stop_pc
))
6884 infrun_debug_printf ("stepped into indirect branch thunk");
6889 if (ecs
->event_thread
->control
.step_range_end
!= 1
6890 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6891 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6892 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
6894 infrun_debug_printf ("stepped into signal trampoline");
6895 /* The inferior, while doing a "step" or "next", has ended up in
6896 a signal trampoline (either by a signal being delivered or by
6897 the signal handler returning). Just single-step until the
6898 inferior leaves the trampoline (either by calling the handler
6904 /* If we're in the return path from a shared library trampoline,
6905 we want to proceed through the trampoline when stepping. */
6906 /* macro/2012-04-25: This needs to come before the subroutine
6907 call check below as on some targets return trampolines look
6908 like subroutine calls (MIPS16 return thunks). */
6909 if (gdbarch_in_solib_return_trampoline (gdbarch
,
6910 ecs
->event_thread
->suspend
.stop_pc
,
6911 ecs
->stop_func_name
)
6912 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6914 /* Determine where this trampoline returns. */
6915 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6916 CORE_ADDR real_stop_pc
6917 = gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6919 infrun_debug_printf ("stepped into solib return tramp");
6921 /* Only proceed through if we know where it's going. */
6924 /* And put the step-breakpoint there and go until there. */
6925 symtab_and_line sr_sal
;
6926 sr_sal
.pc
= real_stop_pc
;
6927 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6928 sr_sal
.pspace
= get_frame_program_space (frame
);
6930 /* Do not specify what the fp should be when we stop since
6931 on some machines the prologue is where the new fp value
6933 insert_step_resume_breakpoint_at_sal (gdbarch
,
6934 sr_sal
, null_frame_id
);
6936 /* Restart without fiddling with the step ranges or
6943 /* Check for subroutine calls. The check for the current frame
6944 equalling the step ID is not necessary - the check of the
6945 previous frame's ID is sufficient - but it is a common case and
6946 cheaper than checking the previous frame's ID.
6948 NOTE: frame_id_eq will never report two invalid frame IDs as
6949 being equal, so to get into this block, both the current and
6950 previous frame must have valid frame IDs. */
6951 /* The outer_frame_id check is a heuristic to detect stepping
6952 through startup code. If we step over an instruction which
6953 sets the stack pointer from an invalid value to a valid value,
6954 we may detect that as a subroutine call from the mythical
6955 "outermost" function. This could be fixed by marking
6956 outermost frames as !stack_p,code_p,special_p. Then the
6957 initial outermost frame, before sp was valid, would
6958 have code_addr == &_start. See the comment in frame_id_eq
6960 if (!frame_id_eq (get_stack_frame_id (frame
),
6961 ecs
->event_thread
->control
.step_stack_frame_id
)
6962 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6963 ecs
->event_thread
->control
.step_stack_frame_id
)
6964 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
6966 || (ecs
->event_thread
->control
.step_start_function
6967 != find_pc_function (ecs
->event_thread
->suspend
.stop_pc
)))))
6969 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6970 CORE_ADDR real_stop_pc
;
6972 infrun_debug_printf ("stepped into subroutine");
6974 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
6976 /* I presume that step_over_calls is only 0 when we're
6977 supposed to be stepping at the assembly language level
6978 ("stepi"). Just stop. */
6979 /* And this works the same backward as frontward. MVS */
6980 end_stepping_range (ecs
);
6984 /* Reverse stepping through solib trampolines. */
6986 if (execution_direction
== EXEC_REVERSE
6987 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6988 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6989 || (ecs
->stop_func_start
== 0
6990 && in_solib_dynsym_resolve_code (stop_pc
))))
6992 /* Any solib trampoline code can be handled in reverse
6993 by simply continuing to single-step. We have already
6994 executed the solib function (backwards), and a few
6995 steps will take us back through the trampoline to the
7001 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
7003 /* We're doing a "next".
7005 Normal (forward) execution: set a breakpoint at the
7006 callee's return address (the address at which the caller
7009 Reverse (backward) execution. set the step-resume
7010 breakpoint at the start of the function that we just
7011 stepped into (backwards), and continue to there. When we
7012 get there, we'll need to single-step back to the caller. */
7014 if (execution_direction
== EXEC_REVERSE
)
7016 /* If we're already at the start of the function, we've either
7017 just stepped backward into a single instruction function,
7018 or stepped back out of a signal handler to the first instruction
7019 of the function. Just keep going, which will single-step back
7021 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
7023 /* Normal function call return (static or dynamic). */
7024 symtab_and_line sr_sal
;
7025 sr_sal
.pc
= ecs
->stop_func_start
;
7026 sr_sal
.pspace
= get_frame_program_space (frame
);
7027 insert_step_resume_breakpoint_at_sal (gdbarch
,
7028 sr_sal
, null_frame_id
);
7032 insert_step_resume_breakpoint_at_caller (frame
);
7038 /* If we are in a function call trampoline (a stub between the
7039 calling routine and the real function), locate the real
7040 function. That's what tells us (a) whether we want to step
7041 into it at all, and (b) what prologue we want to run to the
7042 end of, if we do step into it. */
7043 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
7044 if (real_stop_pc
== 0)
7045 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
7046 if (real_stop_pc
!= 0)
7047 ecs
->stop_func_start
= real_stop_pc
;
7049 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
7051 symtab_and_line sr_sal
;
7052 sr_sal
.pc
= ecs
->stop_func_start
;
7053 sr_sal
.pspace
= get_frame_program_space (frame
);
7055 insert_step_resume_breakpoint_at_sal (gdbarch
,
7056 sr_sal
, null_frame_id
);
7061 /* If we have line number information for the function we are
7062 thinking of stepping into and the function isn't on the skip
7065 If there are several symtabs at that PC (e.g. with include
7066 files), just want to know whether *any* of them have line
7067 numbers. find_pc_line handles this. */
7069 struct symtab_and_line tmp_sal
;
7071 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7072 if (tmp_sal
.line
!= 0
7073 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
7075 && !inline_frame_is_marked_for_skip (true, ecs
->event_thread
))
7077 if (execution_direction
== EXEC_REVERSE
)
7078 handle_step_into_function_backward (gdbarch
, ecs
);
7080 handle_step_into_function (gdbarch
, ecs
);
7085 /* If we have no line number and the step-stop-if-no-debug is
7086 set, we stop the step so that the user has a chance to switch
7087 in assembly mode. */
7088 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
7089 && step_stop_if_no_debug
)
7091 end_stepping_range (ecs
);
7095 if (execution_direction
== EXEC_REVERSE
)
7097 /* If we're already at the start of the function, we've either just
7098 stepped backward into a single instruction function without line
7099 number info, or stepped back out of a signal handler to the first
7100 instruction of the function without line number info. Just keep
7101 going, which will single-step back to the caller. */
7102 if (ecs
->stop_func_start
!= stop_pc
)
7104 /* Set a breakpoint at callee's start address.
7105 From there we can step once and be back in the caller. */
7106 symtab_and_line sr_sal
;
7107 sr_sal
.pc
= ecs
->stop_func_start
;
7108 sr_sal
.pspace
= get_frame_program_space (frame
);
7109 insert_step_resume_breakpoint_at_sal (gdbarch
,
7110 sr_sal
, null_frame_id
);
7114 /* Set a breakpoint at callee's return address (the address
7115 at which the caller will resume). */
7116 insert_step_resume_breakpoint_at_caller (frame
);
7122 /* Reverse stepping through solib trampolines. */
7124 if (execution_direction
== EXEC_REVERSE
7125 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
7127 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
7129 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
7130 || (ecs
->stop_func_start
== 0
7131 && in_solib_dynsym_resolve_code (stop_pc
)))
7133 /* Any solib trampoline code can be handled in reverse
7134 by simply continuing to single-step. We have already
7135 executed the solib function (backwards), and a few
7136 steps will take us back through the trampoline to the
7141 else if (in_solib_dynsym_resolve_code (stop_pc
))
7143 /* Stepped backward into the solib dynsym resolver.
7144 Set a breakpoint at its start and continue, then
7145 one more step will take us out. */
7146 symtab_and_line sr_sal
;
7147 sr_sal
.pc
= ecs
->stop_func_start
;
7148 sr_sal
.pspace
= get_frame_program_space (frame
);
7149 insert_step_resume_breakpoint_at_sal (gdbarch
,
7150 sr_sal
, null_frame_id
);
7156 /* This always returns the sal for the inner-most frame when we are in a
7157 stack of inlined frames, even if GDB actually believes that it is in a
7158 more outer frame. This is checked for below by calls to
7159 inline_skipped_frames. */
7160 stop_pc_sal
= find_pc_line (ecs
->event_thread
->suspend
.stop_pc
, 0);
7162 /* NOTE: tausq/2004-05-24: This if block used to be done before all
7163 the trampoline processing logic, however, there are some trampolines
7164 that have no names, so we should do trampoline handling first. */
7165 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
7166 && ecs
->stop_func_name
== NULL
7167 && stop_pc_sal
.line
== 0)
7169 infrun_debug_printf ("stepped into undebuggable function");
7171 /* The inferior just stepped into, or returned to, an
7172 undebuggable function (where there is no debugging information
7173 and no line number corresponding to the address where the
7174 inferior stopped). Since we want to skip this kind of code,
7175 we keep going until the inferior returns from this
7176 function - unless the user has asked us not to (via
7177 set step-mode) or we no longer know how to get back
7178 to the call site. */
7179 if (step_stop_if_no_debug
7180 || !frame_id_p (frame_unwind_caller_id (frame
)))
7182 /* If we have no line number and the step-stop-if-no-debug
7183 is set, we stop the step so that the user has a chance to
7184 switch in assembly mode. */
7185 end_stepping_range (ecs
);
7190 /* Set a breakpoint at callee's return address (the address
7191 at which the caller will resume). */
7192 insert_step_resume_breakpoint_at_caller (frame
);
7198 if (ecs
->event_thread
->control
.step_range_end
== 1)
7200 /* It is stepi or nexti. We always want to stop stepping after
7202 infrun_debug_printf ("stepi/nexti");
7203 end_stepping_range (ecs
);
7207 if (stop_pc_sal
.line
== 0)
7209 /* We have no line number information. That means to stop
7210 stepping (does this always happen right after one instruction,
7211 when we do "s" in a function with no line numbers,
7212 or can this happen as a result of a return or longjmp?). */
7213 infrun_debug_printf ("line number info");
7214 end_stepping_range (ecs
);
7218 /* Look for "calls" to inlined functions, part one. If the inline
7219 frame machinery detected some skipped call sites, we have entered
7220 a new inline function. */
7222 if (frame_id_eq (get_frame_id (get_current_frame ()),
7223 ecs
->event_thread
->control
.step_frame_id
)
7224 && inline_skipped_frames (ecs
->event_thread
))
7226 infrun_debug_printf ("stepped into inlined function");
7228 symtab_and_line call_sal
= find_frame_sal (get_current_frame ());
7230 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
7232 /* For "step", we're going to stop. But if the call site
7233 for this inlined function is on the same source line as
7234 we were previously stepping, go down into the function
7235 first. Otherwise stop at the call site. */
7237 if (call_sal
.line
== ecs
->event_thread
->current_line
7238 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
7240 step_into_inline_frame (ecs
->event_thread
);
7241 if (inline_frame_is_marked_for_skip (false, ecs
->event_thread
))
7248 end_stepping_range (ecs
);
7253 /* For "next", we should stop at the call site if it is on a
7254 different source line. Otherwise continue through the
7255 inlined function. */
7256 if (call_sal
.line
== ecs
->event_thread
->current_line
7257 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
7260 end_stepping_range (ecs
);
7265 /* Look for "calls" to inlined functions, part two. If we are still
7266 in the same real function we were stepping through, but we have
7267 to go further up to find the exact frame ID, we are stepping
7268 through a more inlined call beyond its call site. */
7270 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
7271 && !frame_id_eq (get_frame_id (get_current_frame ()),
7272 ecs
->event_thread
->control
.step_frame_id
)
7273 && stepped_in_from (get_current_frame (),
7274 ecs
->event_thread
->control
.step_frame_id
))
7276 infrun_debug_printf ("stepping through inlined function");
7278 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
7279 || inline_frame_is_marked_for_skip (false, ecs
->event_thread
))
7282 end_stepping_range (ecs
);
7286 bool refresh_step_info
= true;
7287 if ((ecs
->event_thread
->suspend
.stop_pc
== stop_pc_sal
.pc
)
7288 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
7289 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
7291 /* We are at a different line. */
7293 if (stop_pc_sal
.is_stmt
)
7295 /* We are at the start of a statement.
7297 So stop. Note that we don't stop if we step into the middle of a
7298 statement. That is said to make things like for (;;) statements
7300 infrun_debug_printf ("stepped to a different line");
7301 end_stepping_range (ecs
);
7304 else if (frame_id_eq (get_frame_id (get_current_frame ()),
7305 ecs
->event_thread
->control
.step_frame_id
))
7307 /* We are not at the start of a statement, and we have not changed
7310 We ignore this line table entry, and continue stepping forward,
7311 looking for a better place to stop. */
7312 refresh_step_info
= false;
7313 infrun_debug_printf ("stepped to a different line, but "
7314 "it's not the start of a statement");
7318 /* We are not the start of a statement, and we have changed frame.
7320 We ignore this line table entry, and continue stepping forward,
7321 looking for a better place to stop. Keep refresh_step_info at
7322 true to note that the frame has changed, but ignore the line
7323 number to make sure we don't ignore a subsequent entry with the
7324 same line number. */
7325 stop_pc_sal
.line
= 0;
7326 infrun_debug_printf ("stepped to a different frame, but "
7327 "it's not the start of a statement");
7331 /* We aren't done stepping.
7333 Optimize by setting the stepping range to the line.
7334 (We might not be in the original line, but if we entered a
7335 new line in mid-statement, we continue stepping. This makes
7336 things like for(;;) statements work better.)
7338 If we entered a SAL that indicates a non-statement line table entry,
7339 then we update the stepping range, but we don't update the step info,
7340 which includes things like the line number we are stepping away from.
7341 This means we will stop when we find a line table entry that is marked
7342 as is-statement, even if it matches the non-statement one we just
7345 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
7346 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
7347 ecs
->event_thread
->control
.may_range_step
= 1;
7348 if (refresh_step_info
)
7349 set_step_info (ecs
->event_thread
, frame
, stop_pc_sal
);
7351 infrun_debug_printf ("keep going");
7355 static bool restart_stepped_thread (process_stratum_target
*resume_target
,
7356 ptid_t resume_ptid
);
7358 /* In all-stop mode, if we're currently stepping but have stopped in
7359 some other thread, we may need to switch back to the stepped
7360 thread. Returns true we set the inferior running, false if we left
7361 it stopped (and the event needs further processing). */
7364 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
7366 if (!target_is_non_stop_p ())
7368 /* If any thread is blocked on some internal breakpoint, and we
7369 simply need to step over that breakpoint to get it going
7370 again, do that first. */
7372 /* However, if we see an event for the stepping thread, then we
7373 know all other threads have been moved past their breakpoints
7374 already. Let the caller check whether the step is finished,
7375 etc., before deciding to move it past a breakpoint. */
7376 if (ecs
->event_thread
->control
.step_range_end
!= 0)
7379 /* Check if the current thread is blocked on an incomplete
7380 step-over, interrupted by a random signal. */
7381 if (ecs
->event_thread
->control
.trap_expected
7382 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
7385 ("need to finish step-over of [%s]",
7386 target_pid_to_str (ecs
->event_thread
->ptid
).c_str ());
7391 /* Check if the current thread is blocked by a single-step
7392 breakpoint of another thread. */
7393 if (ecs
->hit_singlestep_breakpoint
)
7395 infrun_debug_printf ("need to step [%s] over single-step breakpoint",
7396 target_pid_to_str (ecs
->ptid
).c_str ());
7401 /* If this thread needs yet another step-over (e.g., stepping
7402 through a delay slot), do it first before moving on to
7404 if (thread_still_needs_step_over (ecs
->event_thread
))
7407 ("thread [%s] still needs step-over",
7408 target_pid_to_str (ecs
->event_thread
->ptid
).c_str ());
7413 /* If scheduler locking applies even if not stepping, there's no
7414 need to walk over threads. Above we've checked whether the
7415 current thread is stepping. If some other thread not the
7416 event thread is stepping, then it must be that scheduler
7417 locking is not in effect. */
7418 if (schedlock_applies (ecs
->event_thread
))
7421 /* Otherwise, we no longer expect a trap in the current thread.
7422 Clear the trap_expected flag before switching back -- this is
7423 what keep_going does as well, if we call it. */
7424 ecs
->event_thread
->control
.trap_expected
= 0;
7426 /* Likewise, clear the signal if it should not be passed. */
7427 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7428 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7430 if (restart_stepped_thread (ecs
->target
, ecs
->ptid
))
7432 prepare_to_wait (ecs
);
7436 switch_to_thread (ecs
->event_thread
);
7442 /* Look for the thread that was stepping, and resume it.
7443 RESUME_TARGET / RESUME_PTID indicate the set of threads the caller
7444 is resuming. Return true if a thread was started, false
7448 restart_stepped_thread (process_stratum_target
*resume_target
,
7451 /* Do all pending step-overs before actually proceeding with
7453 if (start_step_over ())
7456 for (thread_info
*tp
: all_threads_safe ())
7458 if (tp
->state
== THREAD_EXITED
)
7461 if (tp
->suspend
.waitstatus_pending_p
)
7464 /* Ignore threads of processes the caller is not
7467 && (tp
->inf
->process_target () != resume_target
7468 || tp
->inf
->pid
!= resume_ptid
.pid ()))
7471 if (tp
->control
.trap_expected
)
7473 infrun_debug_printf ("switching back to stepped thread (step-over)");
7475 if (keep_going_stepped_thread (tp
))
7480 for (thread_info
*tp
: all_threads_safe ())
7482 if (tp
->state
== THREAD_EXITED
)
7485 if (tp
->suspend
.waitstatus_pending_p
)
7488 /* Ignore threads of processes the caller is not
7491 && (tp
->inf
->process_target () != resume_target
7492 || tp
->inf
->pid
!= resume_ptid
.pid ()))
7495 /* Did we find the stepping thread? */
7496 if (tp
->control
.step_range_end
)
7498 infrun_debug_printf ("switching back to stepped thread (stepping)");
7500 if (keep_going_stepped_thread (tp
))
7511 restart_after_all_stop_detach (process_stratum_target
*proc_target
)
7513 /* Note we don't check target_is_non_stop_p() here, because the
7514 current inferior may no longer have a process_stratum target
7515 pushed, as we just detached. */
7517 /* See if we have a THREAD_RUNNING thread that need to be
7518 re-resumed. If we have any thread that is already executing,
7519 then we don't need to resume the target -- it is already been
7520 resumed. With the remote target (in all-stop), it's even
7521 impossible to issue another resumption if the target is already
7522 resumed, until the target reports a stop. */
7523 for (thread_info
*thr
: all_threads (proc_target
))
7525 if (thr
->state
!= THREAD_RUNNING
)
7528 /* If we have any thread that is already executing, then we
7529 don't need to resume the target -- it is already been
7534 /* If we have a pending event to process, skip resuming the
7535 target and go straight to processing it. */
7536 if (thr
->resumed
&& thr
->suspend
.waitstatus_pending_p
)
7540 /* Alright, we need to re-resume the target. If a thread was
7541 stepping, we need to restart it stepping. */
7542 if (restart_stepped_thread (proc_target
, minus_one_ptid
))
7545 /* Otherwise, find the first THREAD_RUNNING thread and resume
7547 for (thread_info
*thr
: all_threads (proc_target
))
7549 if (thr
->state
!= THREAD_RUNNING
)
7552 execution_control_state ecs
;
7553 reset_ecs (&ecs
, thr
);
7554 switch_to_thread (thr
);
7560 /* Set a previously stepped thread back to stepping. Returns true on
7561 success, false if the resume is not possible (e.g., the thread
7565 keep_going_stepped_thread (struct thread_info
*tp
)
7567 struct frame_info
*frame
;
7568 struct execution_control_state ecss
;
7569 struct execution_control_state
*ecs
= &ecss
;
7571 /* If the stepping thread exited, then don't try to switch back and
7572 resume it, which could fail in several different ways depending
7573 on the target. Instead, just keep going.
7575 We can find a stepping dead thread in the thread list in two
7578 - The target supports thread exit events, and when the target
7579 tries to delete the thread from the thread list, inferior_ptid
7580 pointed at the exiting thread. In such case, calling
7581 delete_thread does not really remove the thread from the list;
7582 instead, the thread is left listed, with 'exited' state.
7584 - The target's debug interface does not support thread exit
7585 events, and so we have no idea whatsoever if the previously
7586 stepping thread is still alive. For that reason, we need to
7587 synchronously query the target now. */
7589 if (tp
->state
== THREAD_EXITED
|| !target_thread_alive (tp
->ptid
))
7591 infrun_debug_printf ("not resuming previously stepped thread, it has "
7598 infrun_debug_printf ("resuming previously stepped thread");
7600 reset_ecs (ecs
, tp
);
7601 switch_to_thread (tp
);
7603 tp
->suspend
.stop_pc
= regcache_read_pc (get_thread_regcache (tp
));
7604 frame
= get_current_frame ();
7606 /* If the PC of the thread we were trying to single-step has
7607 changed, then that thread has trapped or been signaled, but the
7608 event has not been reported to GDB yet. Re-poll the target
7609 looking for this particular thread's event (i.e. temporarily
7610 enable schedlock) by:
7612 - setting a break at the current PC
7613 - resuming that particular thread, only (by setting trap
7616 This prevents us continuously moving the single-step breakpoint
7617 forward, one instruction at a time, overstepping. */
7619 if (tp
->suspend
.stop_pc
!= tp
->prev_pc
)
7623 infrun_debug_printf ("expected thread advanced also (%s -> %s)",
7624 paddress (target_gdbarch (), tp
->prev_pc
),
7625 paddress (target_gdbarch (), tp
->suspend
.stop_pc
));
7627 /* Clear the info of the previous step-over, as it's no longer
7628 valid (if the thread was trying to step over a breakpoint, it
7629 has already succeeded). It's what keep_going would do too,
7630 if we called it. Do this before trying to insert the sss
7631 breakpoint, otherwise if we were previously trying to step
7632 over this exact address in another thread, the breakpoint is
7634 clear_step_over_info ();
7635 tp
->control
.trap_expected
= 0;
7637 insert_single_step_breakpoint (get_frame_arch (frame
),
7638 get_frame_address_space (frame
),
7639 tp
->suspend
.stop_pc
);
7642 resume_ptid
= internal_resume_ptid (tp
->control
.stepping_command
);
7643 do_target_resume (resume_ptid
, false, GDB_SIGNAL_0
);
7647 infrun_debug_printf ("expected thread still hasn't advanced");
7649 keep_going_pass_signal (ecs
);
7655 /* Is thread TP in the middle of (software or hardware)
7656 single-stepping? (Note the result of this function must never be
7657 passed directly as target_resume's STEP parameter.) */
7660 currently_stepping (struct thread_info
*tp
)
7662 return ((tp
->control
.step_range_end
7663 && tp
->control
.step_resume_breakpoint
== NULL
)
7664 || tp
->control
.trap_expected
7665 || tp
->stepped_breakpoint
7666 || bpstat_should_step ());
7669 /* Inferior has stepped into a subroutine call with source code that
7670 we should not step over. Do step to the first line of code in
7674 handle_step_into_function (struct gdbarch
*gdbarch
,
7675 struct execution_control_state
*ecs
)
7677 fill_in_stop_func (gdbarch
, ecs
);
7679 compunit_symtab
*cust
7680 = find_pc_compunit_symtab (ecs
->event_thread
->suspend
.stop_pc
);
7681 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7682 ecs
->stop_func_start
7683 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7685 symtab_and_line stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7686 /* Use the step_resume_break to step until the end of the prologue,
7687 even if that involves jumps (as it seems to on the vax under
7689 /* If the prologue ends in the middle of a source line, continue to
7690 the end of that source line (if it is still within the function).
7691 Otherwise, just go to end of prologue. */
7692 if (stop_func_sal
.end
7693 && stop_func_sal
.pc
!= ecs
->stop_func_start
7694 && stop_func_sal
.end
< ecs
->stop_func_end
)
7695 ecs
->stop_func_start
= stop_func_sal
.end
;
7697 /* Architectures which require breakpoint adjustment might not be able
7698 to place a breakpoint at the computed address. If so, the test
7699 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7700 ecs->stop_func_start to an address at which a breakpoint may be
7701 legitimately placed.
7703 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7704 made, GDB will enter an infinite loop when stepping through
7705 optimized code consisting of VLIW instructions which contain
7706 subinstructions corresponding to different source lines. On
7707 FR-V, it's not permitted to place a breakpoint on any but the
7708 first subinstruction of a VLIW instruction. When a breakpoint is
7709 set, GDB will adjust the breakpoint address to the beginning of
7710 the VLIW instruction. Thus, we need to make the corresponding
7711 adjustment here when computing the stop address. */
7713 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
7715 ecs
->stop_func_start
7716 = gdbarch_adjust_breakpoint_address (gdbarch
,
7717 ecs
->stop_func_start
);
7720 if (ecs
->stop_func_start
== ecs
->event_thread
->suspend
.stop_pc
)
7722 /* We are already there: stop now. */
7723 end_stepping_range (ecs
);
7728 /* Put the step-breakpoint there and go until there. */
7729 symtab_and_line sr_sal
;
7730 sr_sal
.pc
= ecs
->stop_func_start
;
7731 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
7732 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
7734 /* Do not specify what the fp should be when we stop since on
7735 some machines the prologue is where the new fp value is
7737 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
7739 /* And make sure stepping stops right away then. */
7740 ecs
->event_thread
->control
.step_range_end
7741 = ecs
->event_thread
->control
.step_range_start
;
7746 /* Inferior has stepped backward into a subroutine call with source
7747 code that we should not step over. Do step to the beginning of the
7748 last line of code in it. */
7751 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
7752 struct execution_control_state
*ecs
)
7754 struct compunit_symtab
*cust
;
7755 struct symtab_and_line stop_func_sal
;
7757 fill_in_stop_func (gdbarch
, ecs
);
7759 cust
= find_pc_compunit_symtab (ecs
->event_thread
->suspend
.stop_pc
);
7760 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7761 ecs
->stop_func_start
7762 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7764 stop_func_sal
= find_pc_line (ecs
->event_thread
->suspend
.stop_pc
, 0);
7766 /* OK, we're just going to keep stepping here. */
7767 if (stop_func_sal
.pc
== ecs
->event_thread
->suspend
.stop_pc
)
7769 /* We're there already. Just stop stepping now. */
7770 end_stepping_range (ecs
);
7774 /* Else just reset the step range and keep going.
7775 No step-resume breakpoint, they don't work for
7776 epilogues, which can have multiple entry paths. */
7777 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
7778 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
7784 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7785 This is used to both functions and to skip over code. */
7788 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
7789 struct symtab_and_line sr_sal
,
7790 struct frame_id sr_id
,
7791 enum bptype sr_type
)
7793 /* There should never be more than one step-resume or longjmp-resume
7794 breakpoint per thread, so we should never be setting a new
7795 step_resume_breakpoint when one is already active. */
7796 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
7797 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
7799 infrun_debug_printf ("inserting step-resume breakpoint at %s",
7800 paddress (gdbarch
, sr_sal
.pc
));
7802 inferior_thread ()->control
.step_resume_breakpoint
7803 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
).release ();
7807 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
7808 struct symtab_and_line sr_sal
,
7809 struct frame_id sr_id
)
7811 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
7816 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7817 This is used to skip a potential signal handler.
7819 This is called with the interrupted function's frame. The signal
7820 handler, when it returns, will resume the interrupted function at
7824 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
7826 gdb_assert (return_frame
!= NULL
);
7828 struct gdbarch
*gdbarch
= get_frame_arch (return_frame
);
7830 symtab_and_line sr_sal
;
7831 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
7832 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7833 sr_sal
.pspace
= get_frame_program_space (return_frame
);
7835 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
7836 get_stack_frame_id (return_frame
),
7840 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7841 is used to skip a function after stepping into it (for "next" or if
7842 the called function has no debugging information).
7844 The current function has almost always been reached by single
7845 stepping a call or return instruction. NEXT_FRAME belongs to the
7846 current function, and the breakpoint will be set at the caller's
7849 This is a separate function rather than reusing
7850 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7851 get_prev_frame, which may stop prematurely (see the implementation
7852 of frame_unwind_caller_id for an example). */
7855 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
7857 /* We shouldn't have gotten here if we don't know where the call site
7859 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
7861 struct gdbarch
*gdbarch
= frame_unwind_caller_arch (next_frame
);
7863 symtab_and_line sr_sal
;
7864 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
7865 frame_unwind_caller_pc (next_frame
));
7866 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7867 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
7869 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
7870 frame_unwind_caller_id (next_frame
));
7873 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7874 new breakpoint at the target of a jmp_buf. The handling of
7875 longjmp-resume uses the same mechanisms used for handling
7876 "step-resume" breakpoints. */
7879 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
7881 /* There should never be more than one longjmp-resume breakpoint per
7882 thread, so we should never be setting a new
7883 longjmp_resume_breakpoint when one is already active. */
7884 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
7886 infrun_debug_printf ("inserting longjmp-resume breakpoint at %s",
7887 paddress (gdbarch
, pc
));
7889 inferior_thread ()->control
.exception_resume_breakpoint
=
7890 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
).release ();
7893 /* Insert an exception resume breakpoint. TP is the thread throwing
7894 the exception. The block B is the block of the unwinder debug hook
7895 function. FRAME is the frame corresponding to the call to this
7896 function. SYM is the symbol of the function argument holding the
7897 target PC of the exception. */
7900 insert_exception_resume_breakpoint (struct thread_info
*tp
,
7901 const struct block
*b
,
7902 struct frame_info
*frame
,
7907 struct block_symbol vsym
;
7908 struct value
*value
;
7910 struct breakpoint
*bp
;
7912 vsym
= lookup_symbol_search_name (sym
->search_name (),
7914 value
= read_var_value (vsym
.symbol
, vsym
.block
, frame
);
7915 /* If the value was optimized out, revert to the old behavior. */
7916 if (! value_optimized_out (value
))
7918 handler
= value_as_address (value
);
7920 infrun_debug_printf ("exception resume at %lx",
7921 (unsigned long) handler
);
7923 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7925 bp_exception_resume
).release ();
7927 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7930 bp
->thread
= tp
->global_num
;
7931 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7934 catch (const gdb_exception_error
&e
)
7936 /* We want to ignore errors here. */
7940 /* A helper for check_exception_resume that sets an
7941 exception-breakpoint based on a SystemTap probe. */
7944 insert_exception_resume_from_probe (struct thread_info
*tp
,
7945 const struct bound_probe
*probe
,
7946 struct frame_info
*frame
)
7948 struct value
*arg_value
;
7950 struct breakpoint
*bp
;
7952 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
7956 handler
= value_as_address (arg_value
);
7958 infrun_debug_printf ("exception resume at %s",
7959 paddress (probe
->objfile
->arch (), handler
));
7961 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7962 handler
, bp_exception_resume
).release ();
7963 bp
->thread
= tp
->global_num
;
7964 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7967 /* This is called when an exception has been intercepted. Check to
7968 see whether the exception's destination is of interest, and if so,
7969 set an exception resume breakpoint there. */
7972 check_exception_resume (struct execution_control_state
*ecs
,
7973 struct frame_info
*frame
)
7975 struct bound_probe probe
;
7976 struct symbol
*func
;
7978 /* First see if this exception unwinding breakpoint was set via a
7979 SystemTap probe point. If so, the probe has two arguments: the
7980 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7981 set a breakpoint there. */
7982 probe
= find_probe_by_pc (get_frame_pc (frame
));
7985 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
7989 func
= get_frame_function (frame
);
7995 const struct block
*b
;
7996 struct block_iterator iter
;
8000 /* The exception breakpoint is a thread-specific breakpoint on
8001 the unwinder's debug hook, declared as:
8003 void _Unwind_DebugHook (void *cfa, void *handler);
8005 The CFA argument indicates the frame to which control is
8006 about to be transferred. HANDLER is the destination PC.
8008 We ignore the CFA and set a temporary breakpoint at HANDLER.
8009 This is not extremely efficient but it avoids issues in gdb
8010 with computing the DWARF CFA, and it also works even in weird
8011 cases such as throwing an exception from inside a signal
8014 b
= SYMBOL_BLOCK_VALUE (func
);
8015 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
8017 if (!SYMBOL_IS_ARGUMENT (sym
))
8024 insert_exception_resume_breakpoint (ecs
->event_thread
,
8030 catch (const gdb_exception_error
&e
)
8036 stop_waiting (struct execution_control_state
*ecs
)
8038 infrun_debug_printf ("stop_waiting");
8040 /* Let callers know we don't want to wait for the inferior anymore. */
8041 ecs
->wait_some_more
= 0;
8043 /* If all-stop, but there exists a non-stop target, stop all
8044 threads now that we're presenting the stop to the user. */
8045 if (!non_stop
&& exists_non_stop_target ())
8046 stop_all_threads ("presenting stop to user in all-stop");
8049 /* Like keep_going, but passes the signal to the inferior, even if the
8050 signal is set to nopass. */
8053 keep_going_pass_signal (struct execution_control_state
*ecs
)
8055 gdb_assert (ecs
->event_thread
->ptid
== inferior_ptid
);
8056 gdb_assert (!ecs
->event_thread
->resumed
);
8058 /* Save the pc before execution, to compare with pc after stop. */
8059 ecs
->event_thread
->prev_pc
8060 = regcache_read_pc_protected (get_thread_regcache (ecs
->event_thread
));
8062 if (ecs
->event_thread
->control
.trap_expected
)
8064 struct thread_info
*tp
= ecs
->event_thread
;
8066 infrun_debug_printf ("%s has trap_expected set, "
8067 "resuming to collect trap",
8068 target_pid_to_str (tp
->ptid
).c_str ());
8070 /* We haven't yet gotten our trap, and either: intercepted a
8071 non-signal event (e.g., a fork); or took a signal which we
8072 are supposed to pass through to the inferior. Simply
8074 resume (ecs
->event_thread
->suspend
.stop_signal
);
8076 else if (step_over_info_valid_p ())
8078 /* Another thread is stepping over a breakpoint in-line. If
8079 this thread needs a step-over too, queue the request. In
8080 either case, this resume must be deferred for later. */
8081 struct thread_info
*tp
= ecs
->event_thread
;
8083 if (ecs
->hit_singlestep_breakpoint
8084 || thread_still_needs_step_over (tp
))
8086 infrun_debug_printf ("step-over already in progress: "
8087 "step-over for %s deferred",
8088 target_pid_to_str (tp
->ptid
).c_str ());
8089 global_thread_step_over_chain_enqueue (tp
);
8093 infrun_debug_printf ("step-over in progress: resume of %s deferred",
8094 target_pid_to_str (tp
->ptid
).c_str ());
8099 struct regcache
*regcache
= get_current_regcache ();
8102 step_over_what step_what
;
8104 /* Either the trap was not expected, but we are continuing
8105 anyway (if we got a signal, the user asked it be passed to
8108 We got our expected trap, but decided we should resume from
8111 We're going to run this baby now!
8113 Note that insert_breakpoints won't try to re-insert
8114 already inserted breakpoints. Therefore, we don't
8115 care if breakpoints were already inserted, or not. */
8117 /* If we need to step over a breakpoint, and we're not using
8118 displaced stepping to do so, insert all breakpoints
8119 (watchpoints, etc.) but the one we're stepping over, step one
8120 instruction, and then re-insert the breakpoint when that step
8123 step_what
= thread_still_needs_step_over (ecs
->event_thread
);
8125 remove_bp
= (ecs
->hit_singlestep_breakpoint
8126 || (step_what
& STEP_OVER_BREAKPOINT
));
8127 remove_wps
= (step_what
& STEP_OVER_WATCHPOINT
);
8129 /* We can't use displaced stepping if we need to step past a
8130 watchpoint. The instruction copied to the scratch pad would
8131 still trigger the watchpoint. */
8133 && (remove_wps
|| !use_displaced_stepping (ecs
->event_thread
)))
8135 set_step_over_info (regcache
->aspace (),
8136 regcache_read_pc (regcache
), remove_wps
,
8137 ecs
->event_thread
->global_num
);
8139 else if (remove_wps
)
8140 set_step_over_info (NULL
, 0, remove_wps
, -1);
8142 /* If we now need to do an in-line step-over, we need to stop
8143 all other threads. Note this must be done before
8144 insert_breakpoints below, because that removes the breakpoint
8145 we're about to step over, otherwise other threads could miss
8147 if (step_over_info_valid_p () && target_is_non_stop_p ())
8148 stop_all_threads ("starting in-line step-over");
8150 /* Stop stepping if inserting breakpoints fails. */
8153 insert_breakpoints ();
8155 catch (const gdb_exception_error
&e
)
8157 exception_print (gdb_stderr
, e
);
8159 clear_step_over_info ();
8163 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
8165 resume (ecs
->event_thread
->suspend
.stop_signal
);
8168 prepare_to_wait (ecs
);
8171 /* Called when we should continue running the inferior, because the
8172 current event doesn't cause a user visible stop. This does the
8173 resuming part; waiting for the next event is done elsewhere. */
8176 keep_going (struct execution_control_state
*ecs
)
8178 if (ecs
->event_thread
->control
.trap_expected
8179 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
8180 ecs
->event_thread
->control
.trap_expected
= 0;
8182 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
8183 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
8184 keep_going_pass_signal (ecs
);
8187 /* This function normally comes after a resume, before
8188 handle_inferior_event exits. It takes care of any last bits of
8189 housekeeping, and sets the all-important wait_some_more flag. */
8192 prepare_to_wait (struct execution_control_state
*ecs
)
8194 infrun_debug_printf ("prepare_to_wait");
8196 ecs
->wait_some_more
= 1;
8198 /* If the target can't async, emulate it by marking the infrun event
8199 handler such that as soon as we get back to the event-loop, we
8200 immediately end up in fetch_inferior_event again calling
8202 if (!target_can_async_p ())
8203 mark_infrun_async_event_handler ();
8206 /* We are done with the step range of a step/next/si/ni command.
8207 Called once for each n of a "step n" operation. */
8210 end_stepping_range (struct execution_control_state
*ecs
)
8212 ecs
->event_thread
->control
.stop_step
= 1;
8216 /* Several print_*_reason functions to print why the inferior has stopped.
8217 We always print something when the inferior exits, or receives a signal.
8218 The rest of the cases are dealt with later on in normal_stop and
8219 print_it_typical. Ideally there should be a call to one of these
8220 print_*_reason functions functions from handle_inferior_event each time
8221 stop_waiting is called.
8223 Note that we don't call these directly, instead we delegate that to
8224 the interpreters, through observers. Interpreters then call these
8225 with whatever uiout is right. */
8228 print_end_stepping_range_reason (struct ui_out
*uiout
)
8230 /* For CLI-like interpreters, print nothing. */
8232 if (uiout
->is_mi_like_p ())
8234 uiout
->field_string ("reason",
8235 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
8240 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
8242 annotate_signalled ();
8243 if (uiout
->is_mi_like_p ())
8245 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
8246 uiout
->text ("\nProgram terminated with signal ");
8247 annotate_signal_name ();
8248 uiout
->field_string ("signal-name",
8249 gdb_signal_to_name (siggnal
));
8250 annotate_signal_name_end ();
8252 annotate_signal_string ();
8253 uiout
->field_string ("signal-meaning",
8254 gdb_signal_to_string (siggnal
));
8255 annotate_signal_string_end ();
8256 uiout
->text (".\n");
8257 uiout
->text ("The program no longer exists.\n");
8261 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
8263 struct inferior
*inf
= current_inferior ();
8264 std::string pidstr
= target_pid_to_str (ptid_t (inf
->pid
));
8266 annotate_exited (exitstatus
);
8269 if (uiout
->is_mi_like_p ())
8270 uiout
->field_string ("reason", async_reason_lookup (EXEC_ASYNC_EXITED
));
8271 std::string exit_code_str
8272 = string_printf ("0%o", (unsigned int) exitstatus
);
8273 uiout
->message ("[Inferior %s (%s) exited with code %pF]\n",
8274 plongest (inf
->num
), pidstr
.c_str (),
8275 string_field ("exit-code", exit_code_str
.c_str ()));
8279 if (uiout
->is_mi_like_p ())
8281 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
8282 uiout
->message ("[Inferior %s (%s) exited normally]\n",
8283 plongest (inf
->num
), pidstr
.c_str ());
8288 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
8290 struct thread_info
*thr
= inferior_thread ();
8294 if (uiout
->is_mi_like_p ())
8296 else if (show_thread_that_caused_stop ())
8300 uiout
->text ("\nThread ");
8301 uiout
->field_string ("thread-id", print_thread_id (thr
));
8303 name
= thr
->name
!= NULL
? thr
->name
: target_thread_name (thr
);
8306 uiout
->text (" \"");
8307 uiout
->field_string ("name", name
);
8312 uiout
->text ("\nProgram");
8314 if (siggnal
== GDB_SIGNAL_0
&& !uiout
->is_mi_like_p ())
8315 uiout
->text (" stopped");
8318 uiout
->text (" received signal ");
8319 annotate_signal_name ();
8320 if (uiout
->is_mi_like_p ())
8322 ("reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
8323 uiout
->field_string ("signal-name", gdb_signal_to_name (siggnal
));
8324 annotate_signal_name_end ();
8326 annotate_signal_string ();
8327 uiout
->field_string ("signal-meaning", gdb_signal_to_string (siggnal
));
8329 struct regcache
*regcache
= get_current_regcache ();
8330 struct gdbarch
*gdbarch
= regcache
->arch ();
8331 if (gdbarch_report_signal_info_p (gdbarch
))
8332 gdbarch_report_signal_info (gdbarch
, uiout
, siggnal
);
8334 annotate_signal_string_end ();
8336 uiout
->text (".\n");
8340 print_no_history_reason (struct ui_out
*uiout
)
8342 uiout
->text ("\nNo more reverse-execution history.\n");
8345 /* Print current location without a level number, if we have changed
8346 functions or hit a breakpoint. Print source line if we have one.
8347 bpstat_print contains the logic deciding in detail what to print,
8348 based on the event(s) that just occurred. */
8351 print_stop_location (struct target_waitstatus
*ws
)
8354 enum print_what source_flag
;
8355 int do_frame_printing
= 1;
8356 struct thread_info
*tp
= inferior_thread ();
8358 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
8362 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
8363 should) carry around the function and does (or should) use
8364 that when doing a frame comparison. */
8365 if (tp
->control
.stop_step
8366 && frame_id_eq (tp
->control
.step_frame_id
,
8367 get_frame_id (get_current_frame ()))
8368 && (tp
->control
.step_start_function
8369 == find_pc_function (tp
->suspend
.stop_pc
)))
8371 /* Finished step, just print source line. */
8372 source_flag
= SRC_LINE
;
8376 /* Print location and source line. */
8377 source_flag
= SRC_AND_LOC
;
8380 case PRINT_SRC_AND_LOC
:
8381 /* Print location and source line. */
8382 source_flag
= SRC_AND_LOC
;
8384 case PRINT_SRC_ONLY
:
8385 source_flag
= SRC_LINE
;
8388 /* Something bogus. */
8389 source_flag
= SRC_LINE
;
8390 do_frame_printing
= 0;
8393 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
8396 /* The behavior of this routine with respect to the source
8398 SRC_LINE: Print only source line
8399 LOCATION: Print only location
8400 SRC_AND_LOC: Print location and source line. */
8401 if (do_frame_printing
)
8402 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
8408 print_stop_event (struct ui_out
*uiout
, bool displays
)
8410 struct target_waitstatus last
;
8411 struct thread_info
*tp
;
8413 get_last_target_status (nullptr, nullptr, &last
);
8416 scoped_restore save_uiout
= make_scoped_restore (¤t_uiout
, uiout
);
8418 print_stop_location (&last
);
8420 /* Display the auto-display expressions. */
8425 tp
= inferior_thread ();
8426 if (tp
->thread_fsm
!= NULL
8427 && tp
->thread_fsm
->finished_p ())
8429 struct return_value_info
*rv
;
8431 rv
= tp
->thread_fsm
->return_value ();
8433 print_return_value (uiout
, rv
);
8440 maybe_remove_breakpoints (void)
8442 if (!breakpoints_should_be_inserted_now () && target_has_execution ())
8444 if (remove_breakpoints ())
8446 target_terminal::ours_for_output ();
8447 printf_filtered (_("Cannot remove breakpoints because "
8448 "program is no longer writable.\nFurther "
8449 "execution is probably impossible.\n"));
8454 /* The execution context that just caused a normal stop. */
8460 DISABLE_COPY_AND_ASSIGN (stop_context
);
8462 bool changed () const;
8467 /* The event PTID. */
8471 /* If stopp for a thread event, this is the thread that caused the
8473 thread_info_ref thread
;
8475 /* The inferior that caused the stop. */
8479 /* Initializes a new stop context. If stopped for a thread event, this
8480 takes a strong reference to the thread. */
8482 stop_context::stop_context ()
8484 stop_id
= get_stop_id ();
8485 ptid
= inferior_ptid
;
8486 inf_num
= current_inferior ()->num
;
8488 if (inferior_ptid
!= null_ptid
)
8490 /* Take a strong reference so that the thread can't be deleted
8492 thread
= thread_info_ref::new_reference (inferior_thread ());
8496 /* Return true if the current context no longer matches the saved stop
8500 stop_context::changed () const
8502 if (ptid
!= inferior_ptid
)
8504 if (inf_num
!= current_inferior ()->num
)
8506 if (thread
!= NULL
&& thread
->state
!= THREAD_STOPPED
)
8508 if (get_stop_id () != stop_id
)
8518 struct target_waitstatus last
;
8520 get_last_target_status (nullptr, nullptr, &last
);
8524 /* If an exception is thrown from this point on, make sure to
8525 propagate GDB's knowledge of the executing state to the
8526 frontend/user running state. A QUIT is an easy exception to see
8527 here, so do this before any filtered output. */
8529 ptid_t finish_ptid
= null_ptid
;
8532 finish_ptid
= minus_one_ptid
;
8533 else if (last
.kind
== TARGET_WAITKIND_SIGNALLED
8534 || last
.kind
== TARGET_WAITKIND_EXITED
)
8536 /* On some targets, we may still have live threads in the
8537 inferior when we get a process exit event. E.g., for
8538 "checkpoint", when the current checkpoint/fork exits,
8539 linux-fork.c automatically switches to another fork from
8540 within target_mourn_inferior. */
8541 if (inferior_ptid
!= null_ptid
)
8542 finish_ptid
= ptid_t (inferior_ptid
.pid ());
8544 else if (last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8545 finish_ptid
= inferior_ptid
;
8547 gdb::optional
<scoped_finish_thread_state
> maybe_finish_thread_state
;
8548 if (finish_ptid
!= null_ptid
)
8550 maybe_finish_thread_state
.emplace
8551 (user_visible_resume_target (finish_ptid
), finish_ptid
);
8554 /* As we're presenting a stop, and potentially removing breakpoints,
8555 update the thread list so we can tell whether there are threads
8556 running on the target. With target remote, for example, we can
8557 only learn about new threads when we explicitly update the thread
8558 list. Do this before notifying the interpreters about signal
8559 stops, end of stepping ranges, etc., so that the "new thread"
8560 output is emitted before e.g., "Program received signal FOO",
8561 instead of after. */
8562 update_thread_list ();
8564 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
8565 gdb::observers::signal_received
.notify (inferior_thread ()->suspend
.stop_signal
);
8567 /* As with the notification of thread events, we want to delay
8568 notifying the user that we've switched thread context until
8569 the inferior actually stops.
8571 There's no point in saying anything if the inferior has exited.
8572 Note that SIGNALLED here means "exited with a signal", not
8573 "received a signal".
8575 Also skip saying anything in non-stop mode. In that mode, as we
8576 don't want GDB to switch threads behind the user's back, to avoid
8577 races where the user is typing a command to apply to thread x,
8578 but GDB switches to thread y before the user finishes entering
8579 the command, fetch_inferior_event installs a cleanup to restore
8580 the current thread back to the thread the user had selected right
8581 after this event is handled, so we're not really switching, only
8582 informing of a stop. */
8584 && previous_inferior_ptid
!= inferior_ptid
8585 && target_has_execution ()
8586 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
8587 && last
.kind
!= TARGET_WAITKIND_EXITED
8588 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8590 SWITCH_THRU_ALL_UIS ()
8592 target_terminal::ours_for_output ();
8593 printf_filtered (_("[Switching to %s]\n"),
8594 target_pid_to_str (inferior_ptid
).c_str ());
8595 annotate_thread_changed ();
8597 previous_inferior_ptid
= inferior_ptid
;
8600 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
8602 SWITCH_THRU_ALL_UIS ()
8603 if (current_ui
->prompt_state
== PROMPT_BLOCKED
)
8605 target_terminal::ours_for_output ();
8606 printf_filtered (_("No unwaited-for children left.\n"));
8610 /* Note: this depends on the update_thread_list call above. */
8611 maybe_remove_breakpoints ();
8613 /* If an auto-display called a function and that got a signal,
8614 delete that auto-display to avoid an infinite recursion. */
8616 if (stopped_by_random_signal
)
8617 disable_current_display ();
8619 SWITCH_THRU_ALL_UIS ()
8621 async_enable_stdin ();
8624 /* Let the user/frontend see the threads as stopped. */
8625 maybe_finish_thread_state
.reset ();
8627 /* Select innermost stack frame - i.e., current frame is frame 0,
8628 and current location is based on that. Handle the case where the
8629 dummy call is returning after being stopped. E.g. the dummy call
8630 previously hit a breakpoint. (If the dummy call returns
8631 normally, we won't reach here.) Do this before the stop hook is
8632 run, so that it doesn't get to see the temporary dummy frame,
8633 which is not where we'll present the stop. */
8634 if (has_stack_frames ())
8636 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
8638 /* Pop the empty frame that contains the stack dummy. This
8639 also restores inferior state prior to the call (struct
8640 infcall_suspend_state). */
8641 struct frame_info
*frame
= get_current_frame ();
8643 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
8645 /* frame_pop calls reinit_frame_cache as the last thing it
8646 does which means there's now no selected frame. */
8649 select_frame (get_current_frame ());
8651 /* Set the current source location. */
8652 set_current_sal_from_frame (get_current_frame ());
8655 /* Look up the hook_stop and run it (CLI internally handles problem
8656 of stop_command's pre-hook not existing). */
8657 if (stop_command
!= NULL
)
8659 stop_context saved_context
;
8663 execute_cmd_pre_hook (stop_command
);
8665 catch (const gdb_exception
&ex
)
8667 exception_fprintf (gdb_stderr
, ex
,
8668 "Error while running hook_stop:\n");
8671 /* If the stop hook resumes the target, then there's no point in
8672 trying to notify about the previous stop; its context is
8673 gone. Likewise if the command switches thread or inferior --
8674 the observers would print a stop for the wrong
8676 if (saved_context
.changed ())
8680 /* Notify observers about the stop. This is where the interpreters
8681 print the stop event. */
8682 if (inferior_ptid
!= null_ptid
)
8683 gdb::observers::normal_stop
.notify (inferior_thread ()->control
.stop_bpstat
,
8686 gdb::observers::normal_stop
.notify (NULL
, stop_print_frame
);
8688 annotate_stopped ();
8690 if (target_has_execution ())
8692 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
8693 && last
.kind
!= TARGET_WAITKIND_EXITED
8694 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8695 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8696 Delete any breakpoint that is to be deleted at the next stop. */
8697 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
8700 /* Try to get rid of automatically added inferiors that are no
8701 longer needed. Keeping those around slows down things linearly.
8702 Note that this never removes the current inferior. */
8709 signal_stop_state (int signo
)
8711 return signal_stop
[signo
];
8715 signal_print_state (int signo
)
8717 return signal_print
[signo
];
8721 signal_pass_state (int signo
)
8723 return signal_program
[signo
];
8727 signal_cache_update (int signo
)
8731 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
8732 signal_cache_update (signo
);
8737 signal_pass
[signo
] = (signal_stop
[signo
] == 0
8738 && signal_print
[signo
] == 0
8739 && signal_program
[signo
] == 1
8740 && signal_catch
[signo
] == 0);
8744 signal_stop_update (int signo
, int state
)
8746 int ret
= signal_stop
[signo
];
8748 signal_stop
[signo
] = state
;
8749 signal_cache_update (signo
);
8754 signal_print_update (int signo
, int state
)
8756 int ret
= signal_print
[signo
];
8758 signal_print
[signo
] = state
;
8759 signal_cache_update (signo
);
8764 signal_pass_update (int signo
, int state
)
8766 int ret
= signal_program
[signo
];
8768 signal_program
[signo
] = state
;
8769 signal_cache_update (signo
);
8773 /* Update the global 'signal_catch' from INFO and notify the
8777 signal_catch_update (const unsigned int *info
)
8781 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
8782 signal_catch
[i
] = info
[i
] > 0;
8783 signal_cache_update (-1);
8784 target_pass_signals (signal_pass
);
8788 sig_print_header (void)
8790 printf_filtered (_("Signal Stop\tPrint\tPass "
8791 "to program\tDescription\n"));
8795 sig_print_info (enum gdb_signal oursig
)
8797 const char *name
= gdb_signal_to_name (oursig
);
8798 int name_padding
= 13 - strlen (name
);
8800 if (name_padding
<= 0)
8803 printf_filtered ("%s", name
);
8804 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
8805 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
8806 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
8807 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
8808 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
8811 /* Specify how various signals in the inferior should be handled. */
8814 handle_command (const char *args
, int from_tty
)
8816 int digits
, wordlen
;
8817 int sigfirst
, siglast
;
8818 enum gdb_signal oursig
;
8823 error_no_arg (_("signal to handle"));
8826 /* Allocate and zero an array of flags for which signals to handle. */
8828 const size_t nsigs
= GDB_SIGNAL_LAST
;
8829 unsigned char sigs
[nsigs
] {};
8831 /* Break the command line up into args. */
8833 gdb_argv
built_argv (args
);
8835 /* Walk through the args, looking for signal oursigs, signal names, and
8836 actions. Signal numbers and signal names may be interspersed with
8837 actions, with the actions being performed for all signals cumulatively
8838 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8840 for (char *arg
: built_argv
)
8842 wordlen
= strlen (arg
);
8843 for (digits
= 0; isdigit (arg
[digits
]); digits
++)
8847 sigfirst
= siglast
= -1;
8849 if (wordlen
>= 1 && !strncmp (arg
, "all", wordlen
))
8851 /* Apply action to all signals except those used by the
8852 debugger. Silently skip those. */
8855 siglast
= nsigs
- 1;
8857 else if (wordlen
>= 1 && !strncmp (arg
, "stop", wordlen
))
8859 SET_SIGS (nsigs
, sigs
, signal_stop
);
8860 SET_SIGS (nsigs
, sigs
, signal_print
);
8862 else if (wordlen
>= 1 && !strncmp (arg
, "ignore", wordlen
))
8864 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8866 else if (wordlen
>= 2 && !strncmp (arg
, "print", wordlen
))
8868 SET_SIGS (nsigs
, sigs
, signal_print
);
8870 else if (wordlen
>= 2 && !strncmp (arg
, "pass", wordlen
))
8872 SET_SIGS (nsigs
, sigs
, signal_program
);
8874 else if (wordlen
>= 3 && !strncmp (arg
, "nostop", wordlen
))
8876 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8878 else if (wordlen
>= 3 && !strncmp (arg
, "noignore", wordlen
))
8880 SET_SIGS (nsigs
, sigs
, signal_program
);
8882 else if (wordlen
>= 4 && !strncmp (arg
, "noprint", wordlen
))
8884 UNSET_SIGS (nsigs
, sigs
, signal_print
);
8885 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8887 else if (wordlen
>= 4 && !strncmp (arg
, "nopass", wordlen
))
8889 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8891 else if (digits
> 0)
8893 /* It is numeric. The numeric signal refers to our own
8894 internal signal numbering from target.h, not to host/target
8895 signal number. This is a feature; users really should be
8896 using symbolic names anyway, and the common ones like
8897 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8899 sigfirst
= siglast
= (int)
8900 gdb_signal_from_command (atoi (arg
));
8901 if (arg
[digits
] == '-')
8904 gdb_signal_from_command (atoi (arg
+ digits
+ 1));
8906 if (sigfirst
> siglast
)
8908 /* Bet he didn't figure we'd think of this case... */
8909 std::swap (sigfirst
, siglast
);
8914 oursig
= gdb_signal_from_name (arg
);
8915 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
8917 sigfirst
= siglast
= (int) oursig
;
8921 /* Not a number and not a recognized flag word => complain. */
8922 error (_("Unrecognized or ambiguous flag word: \"%s\"."), arg
);
8926 /* If any signal numbers or symbol names were found, set flags for
8927 which signals to apply actions to. */
8929 for (int signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
8931 switch ((enum gdb_signal
) signum
)
8933 case GDB_SIGNAL_TRAP
:
8934 case GDB_SIGNAL_INT
:
8935 if (!allsigs
&& !sigs
[signum
])
8937 if (query (_("%s is used by the debugger.\n\
8938 Are you sure you want to change it? "),
8939 gdb_signal_to_name ((enum gdb_signal
) signum
)))
8944 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8948 case GDB_SIGNAL_DEFAULT
:
8949 case GDB_SIGNAL_UNKNOWN
:
8950 /* Make sure that "all" doesn't print these. */
8959 for (int signum
= 0; signum
< nsigs
; signum
++)
8962 signal_cache_update (-1);
8963 target_pass_signals (signal_pass
);
8964 target_program_signals (signal_program
);
8968 /* Show the results. */
8969 sig_print_header ();
8970 for (; signum
< nsigs
; signum
++)
8972 sig_print_info ((enum gdb_signal
) signum
);
8979 /* Complete the "handle" command. */
8982 handle_completer (struct cmd_list_element
*ignore
,
8983 completion_tracker
&tracker
,
8984 const char *text
, const char *word
)
8986 static const char * const keywords
[] =
9000 signal_completer (ignore
, tracker
, text
, word
);
9001 complete_on_enum (tracker
, keywords
, word
, word
);
9005 gdb_signal_from_command (int num
)
9007 if (num
>= 1 && num
<= 15)
9008 return (enum gdb_signal
) num
;
9009 error (_("Only signals 1-15 are valid as numeric signals.\n\
9010 Use \"info signals\" for a list of symbolic signals."));
9013 /* Print current contents of the tables set by the handle command.
9014 It is possible we should just be printing signals actually used
9015 by the current target (but for things to work right when switching
9016 targets, all signals should be in the signal tables). */
9019 info_signals_command (const char *signum_exp
, int from_tty
)
9021 enum gdb_signal oursig
;
9023 sig_print_header ();
9027 /* First see if this is a symbol name. */
9028 oursig
= gdb_signal_from_name (signum_exp
);
9029 if (oursig
== GDB_SIGNAL_UNKNOWN
)
9031 /* No, try numeric. */
9033 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
9035 sig_print_info (oursig
);
9039 printf_filtered ("\n");
9040 /* These ugly casts brought to you by the native VAX compiler. */
9041 for (oursig
= GDB_SIGNAL_FIRST
;
9042 (int) oursig
< (int) GDB_SIGNAL_LAST
;
9043 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
9047 if (oursig
!= GDB_SIGNAL_UNKNOWN
9048 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
9049 sig_print_info (oursig
);
9052 printf_filtered (_("\nUse the \"handle\" command "
9053 "to change these tables.\n"));
9056 /* The $_siginfo convenience variable is a bit special. We don't know
9057 for sure the type of the value until we actually have a chance to
9058 fetch the data. The type can change depending on gdbarch, so it is
9059 also dependent on which thread you have selected.
9061 1. making $_siginfo be an internalvar that creates a new value on
9064 2. making the value of $_siginfo be an lval_computed value. */
9066 /* This function implements the lval_computed support for reading a
9070 siginfo_value_read (struct value
*v
)
9072 LONGEST transferred
;
9074 /* If we can access registers, so can we access $_siginfo. Likewise
9076 validate_registers_access ();
9079 target_read (current_inferior ()->top_target (),
9080 TARGET_OBJECT_SIGNAL_INFO
,
9082 value_contents_all_raw (v
),
9084 TYPE_LENGTH (value_type (v
)));
9086 if (transferred
!= TYPE_LENGTH (value_type (v
)))
9087 error (_("Unable to read siginfo"));
9090 /* This function implements the lval_computed support for writing a
9094 siginfo_value_write (struct value
*v
, struct value
*fromval
)
9096 LONGEST transferred
;
9098 /* If we can access registers, so can we access $_siginfo. Likewise
9100 validate_registers_access ();
9102 transferred
= target_write (current_inferior ()->top_target (),
9103 TARGET_OBJECT_SIGNAL_INFO
,
9105 value_contents_all_raw (fromval
),
9107 TYPE_LENGTH (value_type (fromval
)));
9109 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
9110 error (_("Unable to write siginfo"));
9113 static const struct lval_funcs siginfo_value_funcs
=
9119 /* Return a new value with the correct type for the siginfo object of
9120 the current thread using architecture GDBARCH. Return a void value
9121 if there's no object available. */
9123 static struct value
*
9124 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
9127 if (target_has_stack ()
9128 && inferior_ptid
!= null_ptid
9129 && gdbarch_get_siginfo_type_p (gdbarch
))
9131 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
9133 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
9136 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
9140 /* infcall_suspend_state contains state about the program itself like its
9141 registers and any signal it received when it last stopped.
9142 This state must be restored regardless of how the inferior function call
9143 ends (either successfully, or after it hits a breakpoint or signal)
9144 if the program is to properly continue where it left off. */
9146 class infcall_suspend_state
9149 /* Capture state from GDBARCH, TP, and REGCACHE that must be restored
9150 once the inferior function call has finished. */
9151 infcall_suspend_state (struct gdbarch
*gdbarch
,
9152 const struct thread_info
*tp
,
9153 struct regcache
*regcache
)
9154 : m_thread_suspend (tp
->suspend
),
9155 m_registers (new readonly_detached_regcache (*regcache
))
9157 gdb::unique_xmalloc_ptr
<gdb_byte
> siginfo_data
;
9159 if (gdbarch_get_siginfo_type_p (gdbarch
))
9161 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
9162 size_t len
= TYPE_LENGTH (type
);
9164 siginfo_data
.reset ((gdb_byte
*) xmalloc (len
));
9166 if (target_read (current_inferior ()->top_target (),
9167 TARGET_OBJECT_SIGNAL_INFO
, NULL
,
9168 siginfo_data
.get (), 0, len
) != len
)
9170 /* Errors ignored. */
9171 siginfo_data
.reset (nullptr);
9177 m_siginfo_gdbarch
= gdbarch
;
9178 m_siginfo_data
= std::move (siginfo_data
);
9182 /* Return a pointer to the stored register state. */
9184 readonly_detached_regcache
*registers () const
9186 return m_registers
.get ();
9189 /* Restores the stored state into GDBARCH, TP, and REGCACHE. */
9191 void restore (struct gdbarch
*gdbarch
,
9192 struct thread_info
*tp
,
9193 struct regcache
*regcache
) const
9195 tp
->suspend
= m_thread_suspend
;
9197 if (m_siginfo_gdbarch
== gdbarch
)
9199 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
9201 /* Errors ignored. */
9202 target_write (current_inferior ()->top_target (),
9203 TARGET_OBJECT_SIGNAL_INFO
, NULL
,
9204 m_siginfo_data
.get (), 0, TYPE_LENGTH (type
));
9207 /* The inferior can be gone if the user types "print exit(0)"
9208 (and perhaps other times). */
9209 if (target_has_execution ())
9210 /* NB: The register write goes through to the target. */
9211 regcache
->restore (registers ());
9215 /* How the current thread stopped before the inferior function call was
9217 struct thread_suspend_state m_thread_suspend
;
9219 /* The registers before the inferior function call was executed. */
9220 std::unique_ptr
<readonly_detached_regcache
> m_registers
;
9222 /* Format of SIGINFO_DATA or NULL if it is not present. */
9223 struct gdbarch
*m_siginfo_gdbarch
= nullptr;
9225 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
9226 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
9227 content would be invalid. */
9228 gdb::unique_xmalloc_ptr
<gdb_byte
> m_siginfo_data
;
9231 infcall_suspend_state_up
9232 save_infcall_suspend_state ()
9234 struct thread_info
*tp
= inferior_thread ();
9235 struct regcache
*regcache
= get_current_regcache ();
9236 struct gdbarch
*gdbarch
= regcache
->arch ();
9238 infcall_suspend_state_up inf_state
9239 (new struct infcall_suspend_state (gdbarch
, tp
, regcache
));
9241 /* Having saved the current state, adjust the thread state, discarding
9242 any stop signal information. The stop signal is not useful when
9243 starting an inferior function call, and run_inferior_call will not use
9244 the signal due to its `proceed' call with GDB_SIGNAL_0. */
9245 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
9250 /* Restore inferior session state to INF_STATE. */
9253 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
9255 struct thread_info
*tp
= inferior_thread ();
9256 struct regcache
*regcache
= get_current_regcache ();
9257 struct gdbarch
*gdbarch
= regcache
->arch ();
9259 inf_state
->restore (gdbarch
, tp
, regcache
);
9260 discard_infcall_suspend_state (inf_state
);
9264 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
9269 readonly_detached_regcache
*
9270 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
9272 return inf_state
->registers ();
9275 /* infcall_control_state contains state regarding gdb's control of the
9276 inferior itself like stepping control. It also contains session state like
9277 the user's currently selected frame. */
9279 struct infcall_control_state
9281 struct thread_control_state thread_control
;
9282 struct inferior_control_state inferior_control
;
9285 enum stop_stack_kind stop_stack_dummy
= STOP_NONE
;
9286 int stopped_by_random_signal
= 0;
9288 /* ID and level of the selected frame when the inferior function
9290 struct frame_id selected_frame_id
{};
9291 int selected_frame_level
= -1;
9294 /* Save all of the information associated with the inferior<==>gdb
9297 infcall_control_state_up
9298 save_infcall_control_state ()
9300 infcall_control_state_up
inf_status (new struct infcall_control_state
);
9301 struct thread_info
*tp
= inferior_thread ();
9302 struct inferior
*inf
= current_inferior ();
9304 inf_status
->thread_control
= tp
->control
;
9305 inf_status
->inferior_control
= inf
->control
;
9307 tp
->control
.step_resume_breakpoint
= NULL
;
9308 tp
->control
.exception_resume_breakpoint
= NULL
;
9310 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
9311 chain. If caller's caller is walking the chain, they'll be happier if we
9312 hand them back the original chain when restore_infcall_control_state is
9314 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
9317 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
9318 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
9320 save_selected_frame (&inf_status
->selected_frame_id
,
9321 &inf_status
->selected_frame_level
);
9326 /* Restore inferior session state to INF_STATUS. */
9329 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
9331 struct thread_info
*tp
= inferior_thread ();
9332 struct inferior
*inf
= current_inferior ();
9334 if (tp
->control
.step_resume_breakpoint
)
9335 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
9337 if (tp
->control
.exception_resume_breakpoint
)
9338 tp
->control
.exception_resume_breakpoint
->disposition
9339 = disp_del_at_next_stop
;
9341 /* Handle the bpstat_copy of the chain. */
9342 bpstat_clear (&tp
->control
.stop_bpstat
);
9344 tp
->control
= inf_status
->thread_control
;
9345 inf
->control
= inf_status
->inferior_control
;
9348 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
9349 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
9351 if (target_has_stack ())
9353 restore_selected_frame (inf_status
->selected_frame_id
,
9354 inf_status
->selected_frame_level
);
9361 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
9363 if (inf_status
->thread_control
.step_resume_breakpoint
)
9364 inf_status
->thread_control
.step_resume_breakpoint
->disposition
9365 = disp_del_at_next_stop
;
9367 if (inf_status
->thread_control
.exception_resume_breakpoint
)
9368 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
9369 = disp_del_at_next_stop
;
9371 /* See save_infcall_control_state for info on stop_bpstat. */
9372 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
9380 clear_exit_convenience_vars (void)
9382 clear_internalvar (lookup_internalvar ("_exitsignal"));
9383 clear_internalvar (lookup_internalvar ("_exitcode"));
9387 /* User interface for reverse debugging:
9388 Set exec-direction / show exec-direction commands
9389 (returns error unless target implements to_set_exec_direction method). */
9391 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
9392 static const char exec_forward
[] = "forward";
9393 static const char exec_reverse
[] = "reverse";
9394 static const char *exec_direction
= exec_forward
;
9395 static const char *const exec_direction_names
[] = {
9402 set_exec_direction_func (const char *args
, int from_tty
,
9403 struct cmd_list_element
*cmd
)
9405 if (target_can_execute_reverse ())
9407 if (!strcmp (exec_direction
, exec_forward
))
9408 execution_direction
= EXEC_FORWARD
;
9409 else if (!strcmp (exec_direction
, exec_reverse
))
9410 execution_direction
= EXEC_REVERSE
;
9414 exec_direction
= exec_forward
;
9415 error (_("Target does not support this operation."));
9420 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
9421 struct cmd_list_element
*cmd
, const char *value
)
9423 switch (execution_direction
) {
9425 fprintf_filtered (out
, _("Forward.\n"));
9428 fprintf_filtered (out
, _("Reverse.\n"));
9431 internal_error (__FILE__
, __LINE__
,
9432 _("bogus execution_direction value: %d"),
9433 (int) execution_direction
);
9438 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
9439 struct cmd_list_element
*c
, const char *value
)
9441 fprintf_filtered (file
, _("Resuming the execution of threads "
9442 "of all processes is %s.\n"), value
);
9445 /* Implementation of `siginfo' variable. */
9447 static const struct internalvar_funcs siginfo_funcs
=
9454 /* Callback for infrun's target events source. This is marked when a
9455 thread has a pending status to process. */
9458 infrun_async_inferior_event_handler (gdb_client_data data
)
9460 clear_async_event_handler (infrun_async_inferior_event_token
);
9461 inferior_event_handler (INF_REG_EVENT
);
9468 /* Verify that when two threads with the same ptid exist (from two different
9469 targets) and one of them changes ptid, we only update inferior_ptid if
9470 it is appropriate. */
9473 infrun_thread_ptid_changed ()
9475 gdbarch
*arch
= current_inferior ()->gdbarch
;
9477 /* The thread which inferior_ptid represents changes ptid. */
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 (&target1
.mock_inferior
);
9496 thread_change_ptid (&target1
.mock_target
, old_ptid
, new_ptid
);
9498 gdb_assert (inferior_ptid
== new_ptid
);
9501 /* A thread with the same ptid as inferior_ptid, but from another target,
9504 scoped_restore_current_pspace_and_thread restore
;
9506 scoped_mock_context
<test_target_ops
> target1 (arch
);
9507 scoped_mock_context
<test_target_ops
> target2 (arch
);
9508 target2
.mock_inferior
.next
= &target1
.mock_inferior
;
9510 ptid_t
old_ptid (111, 222);
9511 ptid_t
new_ptid (111, 333);
9513 target1
.mock_inferior
.pid
= old_ptid
.pid ();
9514 target1
.mock_thread
.ptid
= old_ptid
;
9515 target2
.mock_inferior
.pid
= old_ptid
.pid ();
9516 target2
.mock_thread
.ptid
= old_ptid
;
9518 auto restore_inferior_ptid
= make_scoped_restore (&inferior_ptid
, old_ptid
);
9519 set_current_inferior (&target2
.mock_inferior
);
9521 thread_change_ptid (&target1
.mock_target
, old_ptid
, new_ptid
);
9523 gdb_assert (inferior_ptid
== old_ptid
);
9527 } /* namespace selftests */
9529 #endif /* GDB_SELF_TEST */
9531 void _initialize_infrun ();
9533 _initialize_infrun ()
9535 struct cmd_list_element
*c
;
9537 /* Register extra event sources in the event loop. */
9538 infrun_async_inferior_event_token
9539 = create_async_event_handler (infrun_async_inferior_event_handler
, NULL
,
9542 cmd_list_element
*info_signals_cmd
9543 = add_info ("signals", info_signals_command
, _("\
9544 What debugger does when program gets various signals.\n\
9545 Specify a signal as argument to print info on that signal only."));
9546 add_info_alias ("handle", info_signals_cmd
, 0);
9548 c
= add_com ("handle", class_run
, handle_command
, _("\
9549 Specify how to handle signals.\n\
9550 Usage: handle SIGNAL [ACTIONS]\n\
9551 Args are signals and actions to apply to those signals.\n\
9552 If no actions are specified, the current settings for the specified signals\n\
9553 will be displayed instead.\n\
9555 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
9556 from 1-15 are allowed for compatibility with old versions of GDB.\n\
9557 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
9558 The special arg \"all\" is recognized to mean all signals except those\n\
9559 used by the debugger, typically SIGTRAP and SIGINT.\n\
9561 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
9562 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
9563 Stop means reenter debugger if this signal happens (implies print).\n\
9564 Print means print a message if this signal happens.\n\
9565 Pass means let program see this signal; otherwise program doesn't know.\n\
9566 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
9567 Pass and Stop may be combined.\n\
9569 Multiple signals may be specified. Signal numbers and signal names\n\
9570 may be interspersed with actions, with the actions being performed for\n\
9571 all signals cumulatively specified."));
9572 set_cmd_completer (c
, handle_completer
);
9575 stop_command
= add_cmd ("stop", class_obscure
,
9576 not_just_help_class_command
, _("\
9577 There is no `stop' command, but you can set a hook on `stop'.\n\
9578 This allows you to set a list of commands to be run each time execution\n\
9579 of the program stops."), &cmdlist
);
9581 add_setshow_boolean_cmd
9582 ("infrun", class_maintenance
, &debug_infrun
,
9583 _("Set inferior debugging."),
9584 _("Show inferior debugging."),
9585 _("When non-zero, inferior specific debugging is enabled."),
9586 NULL
, show_debug_infrun
, &setdebuglist
, &showdebuglist
);
9588 add_setshow_boolean_cmd ("non-stop", no_class
,
9590 Set whether gdb controls the inferior in non-stop mode."), _("\
9591 Show whether gdb controls the inferior in non-stop mode."), _("\
9592 When debugging a multi-threaded program and this setting is\n\
9593 off (the default, also called all-stop mode), when one thread stops\n\
9594 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9595 all other threads in the program while you interact with the thread of\n\
9596 interest. When you continue or step a thread, you can allow the other\n\
9597 threads to run, or have them remain stopped, but while you inspect any\n\
9598 thread's state, all threads stop.\n\
9600 In non-stop mode, when one thread stops, other threads can continue\n\
9601 to run freely. You'll be able to step each thread independently,\n\
9602 leave it stopped or free to run as needed."),
9608 for (size_t i
= 0; i
< GDB_SIGNAL_LAST
; i
++)
9611 signal_print
[i
] = 1;
9612 signal_program
[i
] = 1;
9613 signal_catch
[i
] = 0;
9616 /* Signals caused by debugger's own actions should not be given to
9617 the program afterwards.
9619 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9620 explicitly specifies that it should be delivered to the target
9621 program. Typically, that would occur when a user is debugging a
9622 target monitor on a simulator: the target monitor sets a
9623 breakpoint; the simulator encounters this breakpoint and halts
9624 the simulation handing control to GDB; GDB, noting that the stop
9625 address doesn't map to any known breakpoint, returns control back
9626 to the simulator; the simulator then delivers the hardware
9627 equivalent of a GDB_SIGNAL_TRAP to the program being
9629 signal_program
[GDB_SIGNAL_TRAP
] = 0;
9630 signal_program
[GDB_SIGNAL_INT
] = 0;
9632 /* Signals that are not errors should not normally enter the debugger. */
9633 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
9634 signal_print
[GDB_SIGNAL_ALRM
] = 0;
9635 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
9636 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
9637 signal_stop
[GDB_SIGNAL_PROF
] = 0;
9638 signal_print
[GDB_SIGNAL_PROF
] = 0;
9639 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
9640 signal_print
[GDB_SIGNAL_CHLD
] = 0;
9641 signal_stop
[GDB_SIGNAL_IO
] = 0;
9642 signal_print
[GDB_SIGNAL_IO
] = 0;
9643 signal_stop
[GDB_SIGNAL_POLL
] = 0;
9644 signal_print
[GDB_SIGNAL_POLL
] = 0;
9645 signal_stop
[GDB_SIGNAL_URG
] = 0;
9646 signal_print
[GDB_SIGNAL_URG
] = 0;
9647 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
9648 signal_print
[GDB_SIGNAL_WINCH
] = 0;
9649 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
9650 signal_print
[GDB_SIGNAL_PRIO
] = 0;
9652 /* These signals are used internally by user-level thread
9653 implementations. (See signal(5) on Solaris.) Like the above
9654 signals, a healthy program receives and handles them as part of
9655 its normal operation. */
9656 signal_stop
[GDB_SIGNAL_LWP
] = 0;
9657 signal_print
[GDB_SIGNAL_LWP
] = 0;
9658 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
9659 signal_print
[GDB_SIGNAL_WAITING
] = 0;
9660 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
9661 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
9662 signal_stop
[GDB_SIGNAL_LIBRT
] = 0;
9663 signal_print
[GDB_SIGNAL_LIBRT
] = 0;
9665 /* Update cached state. */
9666 signal_cache_update (-1);
9668 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
9669 &stop_on_solib_events
, _("\
9670 Set stopping for shared library events."), _("\
9671 Show stopping for shared library events."), _("\
9672 If nonzero, gdb will give control to the user when the dynamic linker\n\
9673 notifies gdb of shared library events. The most common event of interest\n\
9674 to the user would be loading/unloading of a new library."),
9675 set_stop_on_solib_events
,
9676 show_stop_on_solib_events
,
9677 &setlist
, &showlist
);
9679 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
9680 follow_fork_mode_kind_names
,
9681 &follow_fork_mode_string
, _("\
9682 Set debugger response to a program call of fork or vfork."), _("\
9683 Show debugger response to a program call of fork or vfork."), _("\
9684 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9685 parent - the original process is debugged after a fork\n\
9686 child - the new process is debugged after a fork\n\
9687 The unfollowed process will continue to run.\n\
9688 By default, the debugger will follow the parent process."),
9690 show_follow_fork_mode_string
,
9691 &setlist
, &showlist
);
9693 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
9694 follow_exec_mode_names
,
9695 &follow_exec_mode_string
, _("\
9696 Set debugger response to a program call of exec."), _("\
9697 Show debugger response to a program call of exec."), _("\
9698 An exec call replaces the program image of a process.\n\
9700 follow-exec-mode can be:\n\
9702 new - the debugger creates a new inferior and rebinds the process\n\
9703 to this new inferior. The program the process was running before\n\
9704 the exec call can be restarted afterwards by restarting the original\n\
9707 same - the debugger keeps the process bound to the same inferior.\n\
9708 The new executable image replaces the previous executable loaded in\n\
9709 the inferior. Restarting the inferior after the exec call restarts\n\
9710 the executable the process was running after the exec call.\n\
9712 By default, the debugger will use the same inferior."),
9714 show_follow_exec_mode_string
,
9715 &setlist
, &showlist
);
9717 add_setshow_enum_cmd ("scheduler-locking", class_run
,
9718 scheduler_enums
, &scheduler_mode
, _("\
9719 Set mode for locking scheduler during execution."), _("\
9720 Show mode for locking scheduler during execution."), _("\
9721 off == no locking (threads may preempt at any time)\n\
9722 on == full locking (no thread except the current thread may run)\n\
9723 This applies to both normal execution and replay mode.\n\
9724 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9725 In this mode, other threads may run during other commands.\n\
9726 This applies to both normal execution and replay mode.\n\
9727 replay == scheduler locked in replay mode and unlocked during normal execution."),
9728 set_schedlock_func
, /* traps on target vector */
9729 show_scheduler_mode
,
9730 &setlist
, &showlist
);
9732 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
9733 Set mode for resuming threads of all processes."), _("\
9734 Show mode for resuming threads of all processes."), _("\
9735 When on, execution commands (such as 'continue' or 'next') resume all\n\
9736 threads of all processes. When off (which is the default), execution\n\
9737 commands only resume the threads of the current process. The set of\n\
9738 threads that are resumed is further refined by the scheduler-locking\n\
9739 mode (see help set scheduler-locking)."),
9741 show_schedule_multiple
,
9742 &setlist
, &showlist
);
9744 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
9745 Set mode of the step operation."), _("\
9746 Show mode of the step operation."), _("\
9747 When set, doing a step over a function without debug line information\n\
9748 will stop at the first instruction of that function. Otherwise, the\n\
9749 function is skipped and the step command stops at a different source line."),
9751 show_step_stop_if_no_debug
,
9752 &setlist
, &showlist
);
9754 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
9755 &can_use_displaced_stepping
, _("\
9756 Set debugger's willingness to use displaced stepping."), _("\
9757 Show debugger's willingness to use displaced stepping."), _("\
9758 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9759 supported by the target architecture. If off, gdb will not use displaced\n\
9760 stepping to step over breakpoints, even if such is supported by the target\n\
9761 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9762 if the target architecture supports it and non-stop mode is active, but will not\n\
9763 use it in all-stop mode (see help set non-stop)."),
9765 show_can_use_displaced_stepping
,
9766 &setlist
, &showlist
);
9768 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
9769 &exec_direction
, _("Set direction of execution.\n\
9770 Options are 'forward' or 'reverse'."),
9771 _("Show direction of execution (forward/reverse)."),
9772 _("Tells gdb whether to execute forward or backward."),
9773 set_exec_direction_func
, show_exec_direction_func
,
9774 &setlist
, &showlist
);
9776 /* Set/show detach-on-fork: user-settable mode. */
9778 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
9779 Set whether gdb will detach the child of a fork."), _("\
9780 Show whether gdb will detach the child of a fork."), _("\
9781 Tells gdb whether to detach the child of a fork."),
9782 NULL
, NULL
, &setlist
, &showlist
);
9784 /* Set/show disable address space randomization mode. */
9786 add_setshow_boolean_cmd ("disable-randomization", class_support
,
9787 &disable_randomization
, _("\
9788 Set disabling of debuggee's virtual address space randomization."), _("\
9789 Show disabling of debuggee's virtual address space randomization."), _("\
9790 When this mode is on (which is the default), randomization of the virtual\n\
9791 address space is disabled. Standalone programs run with the randomization\n\
9792 enabled by default on some platforms."),
9793 &set_disable_randomization
,
9794 &show_disable_randomization
,
9795 &setlist
, &showlist
);
9797 /* ptid initializations */
9798 inferior_ptid
= null_ptid
;
9799 target_last_wait_ptid
= minus_one_ptid
;
9801 gdb::observers::thread_ptid_changed
.attach (infrun_thread_ptid_changed
,
9803 gdb::observers::thread_stop_requested
.attach (infrun_thread_stop_requested
,
9805 gdb::observers::thread_exit
.attach (infrun_thread_thread_exit
, "infrun");
9806 gdb::observers::inferior_exit
.attach (infrun_inferior_exit
, "infrun");
9807 gdb::observers::inferior_execd
.attach (infrun_inferior_execd
, "infrun");
9809 /* Explicitly create without lookup, since that tries to create a
9810 value with a void typed value, and when we get here, gdbarch
9811 isn't initialized yet. At this point, we're quite sure there
9812 isn't another convenience variable of the same name. */
9813 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
9815 add_setshow_boolean_cmd ("observer", no_class
,
9816 &observer_mode_1
, _("\
9817 Set whether gdb controls the inferior in observer mode."), _("\
9818 Show whether gdb controls the inferior in observer mode."), _("\
9819 In observer mode, GDB can get data from the inferior, but not\n\
9820 affect its execution. Registers and memory may not be changed,\n\
9821 breakpoints may not be set, and the program cannot be interrupted\n\
9829 selftests::register_test ("infrun_thread_ptid_changed",
9830 selftests::infrun_thread_ptid_changed
);