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 infrun_debug_printf ("resume_ptid=%s, step=%d, sig=%s",
2187 resume_ptid
.to_string ().c_str (),
2188 step
, gdb_signal_to_symbol_string (sig
));
2190 target_resume (resume_ptid
, step
, sig
);
2192 if (target_can_async_p ())
2196 /* Resume the inferior. SIG is the signal to give the inferior
2197 (GDB_SIGNAL_0 for none). Note: don't call this directly; instead
2198 call 'resume', which handles exceptions. */
2201 resume_1 (enum gdb_signal sig
)
2203 struct regcache
*regcache
= get_current_regcache ();
2204 struct gdbarch
*gdbarch
= regcache
->arch ();
2205 struct thread_info
*tp
= inferior_thread ();
2206 const address_space
*aspace
= regcache
->aspace ();
2208 /* This represents the user's step vs continue request. When
2209 deciding whether "set scheduler-locking step" applies, it's the
2210 user's intention that counts. */
2211 const int user_step
= tp
->control
.stepping_command
;
2212 /* This represents what we'll actually request the target to do.
2213 This can decay from a step to a continue, if e.g., we need to
2214 implement single-stepping with breakpoints (software
2218 gdb_assert (!tp
->stop_requested
);
2219 gdb_assert (!thread_is_in_step_over_chain (tp
));
2221 if (tp
->suspend
.waitstatus_pending_p
)
2224 ("thread %s has pending wait "
2225 "status %s (currently_stepping=%d).",
2226 target_pid_to_str (tp
->ptid
).c_str (),
2227 target_waitstatus_to_string (&tp
->suspend
.waitstatus
).c_str (),
2228 currently_stepping (tp
));
2230 tp
->inf
->process_target ()->threads_executing
= true;
2233 /* FIXME: What should we do if we are supposed to resume this
2234 thread with a signal? Maybe we should maintain a queue of
2235 pending signals to deliver. */
2236 if (sig
!= GDB_SIGNAL_0
)
2238 warning (_("Couldn't deliver signal %s to %s."),
2239 gdb_signal_to_name (sig
),
2240 target_pid_to_str (tp
->ptid
).c_str ());
2243 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2245 if (target_can_async_p ())
2248 /* Tell the event loop we have an event to process. */
2249 mark_async_event_handler (infrun_async_inferior_event_token
);
2254 tp
->stepped_breakpoint
= 0;
2256 /* Depends on stepped_breakpoint. */
2257 step
= currently_stepping (tp
);
2259 if (current_inferior ()->thread_waiting_for_vfork_done
!= nullptr)
2261 /* Don't try to single-step a vfork parent that is waiting for
2262 the child to get out of the shared memory region (by exec'ing
2263 or exiting). This is particularly important on software
2264 single-step archs, as the child process would trip on the
2265 software single step breakpoint inserted for the parent
2266 process. Since the parent will not actually execute any
2267 instruction until the child is out of the shared region (such
2268 are vfork's semantics), it is safe to simply continue it.
2269 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2270 the parent, and tell it to `keep_going', which automatically
2271 re-sets it stepping. */
2272 infrun_debug_printf ("resume : clear step");
2276 CORE_ADDR pc
= regcache_read_pc (regcache
);
2278 infrun_debug_printf ("step=%d, signal=%s, trap_expected=%d, "
2279 "current thread [%s] at %s",
2280 step
, gdb_signal_to_symbol_string (sig
),
2281 tp
->control
.trap_expected
,
2282 target_pid_to_str (inferior_ptid
).c_str (),
2283 paddress (gdbarch
, pc
));
2285 /* Normally, by the time we reach `resume', the breakpoints are either
2286 removed or inserted, as appropriate. The exception is if we're sitting
2287 at a permanent breakpoint; we need to step over it, but permanent
2288 breakpoints can't be removed. So we have to test for it here. */
2289 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2291 if (sig
!= GDB_SIGNAL_0
)
2293 /* We have a signal to pass to the inferior. The resume
2294 may, or may not take us to the signal handler. If this
2295 is a step, we'll need to stop in the signal handler, if
2296 there's one, (if the target supports stepping into
2297 handlers), or in the next mainline instruction, if
2298 there's no handler. If this is a continue, we need to be
2299 sure to run the handler with all breakpoints inserted.
2300 In all cases, set a breakpoint at the current address
2301 (where the handler returns to), and once that breakpoint
2302 is hit, resume skipping the permanent breakpoint. If
2303 that breakpoint isn't hit, then we've stepped into the
2304 signal handler (or hit some other event). We'll delete
2305 the step-resume breakpoint then. */
2307 infrun_debug_printf ("resume: skipping permanent breakpoint, "
2308 "deliver signal first");
2310 clear_step_over_info ();
2311 tp
->control
.trap_expected
= 0;
2313 if (tp
->control
.step_resume_breakpoint
== NULL
)
2315 /* Set a "high-priority" step-resume, as we don't want
2316 user breakpoints at PC to trigger (again) when this
2318 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2319 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2321 tp
->step_after_step_resume_breakpoint
= step
;
2324 insert_breakpoints ();
2328 /* There's no signal to pass, we can go ahead and skip the
2329 permanent breakpoint manually. */
2330 infrun_debug_printf ("skipping permanent breakpoint");
2331 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2332 /* Update pc to reflect the new address from which we will
2333 execute instructions. */
2334 pc
= regcache_read_pc (regcache
);
2338 /* We've already advanced the PC, so the stepping part
2339 is done. Now we need to arrange for a trap to be
2340 reported to handle_inferior_event. Set a breakpoint
2341 at the current PC, and run to it. Don't update
2342 prev_pc, because if we end in
2343 switch_back_to_stepped_thread, we want the "expected
2344 thread advanced also" branch to be taken. IOW, we
2345 don't want this thread to step further from PC
2347 gdb_assert (!step_over_info_valid_p ());
2348 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2349 insert_breakpoints ();
2351 resume_ptid
= internal_resume_ptid (user_step
);
2352 do_target_resume (resume_ptid
, false, GDB_SIGNAL_0
);
2359 /* If we have a breakpoint to step over, make sure to do a single
2360 step only. Same if we have software watchpoints. */
2361 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2362 tp
->control
.may_range_step
= 0;
2364 /* If displaced stepping is enabled, step over breakpoints by executing a
2365 copy of the instruction at a different address.
2367 We can't use displaced stepping when we have a signal to deliver;
2368 the comments for displaced_step_prepare explain why. The
2369 comments in the handle_inferior event for dealing with 'random
2370 signals' explain what we do instead.
2372 We can't use displaced stepping when we are waiting for vfork_done
2373 event, displaced stepping breaks the vfork child similarly as single
2374 step software breakpoint. */
2375 if (tp
->control
.trap_expected
2376 && use_displaced_stepping (tp
)
2377 && !step_over_info_valid_p ()
2378 && sig
== GDB_SIGNAL_0
2379 && current_inferior ()->thread_waiting_for_vfork_done
== nullptr)
2381 displaced_step_prepare_status prepare_status
2382 = displaced_step_prepare (tp
);
2384 if (prepare_status
== DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE
)
2386 infrun_debug_printf ("Got placed in step-over queue");
2388 tp
->control
.trap_expected
= 0;
2391 else if (prepare_status
== DISPLACED_STEP_PREPARE_STATUS_CANT
)
2393 /* Fallback to stepping over the breakpoint in-line. */
2395 if (target_is_non_stop_p ())
2396 stop_all_threads ("displaced stepping falling back on inline stepping");
2398 set_step_over_info (regcache
->aspace (),
2399 regcache_read_pc (regcache
), 0, tp
->global_num
);
2401 step
= maybe_software_singlestep (gdbarch
, pc
);
2403 insert_breakpoints ();
2405 else if (prepare_status
== DISPLACED_STEP_PREPARE_STATUS_OK
)
2407 /* Update pc to reflect the new address from which we will
2408 execute instructions due to displaced stepping. */
2409 pc
= regcache_read_pc (get_thread_regcache (tp
));
2411 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
);
2414 gdb_assert_not_reached (_("Invalid displaced_step_prepare_status "
2418 /* Do we need to do it the hard way, w/temp breakpoints? */
2420 step
= maybe_software_singlestep (gdbarch
, pc
);
2422 /* Currently, our software single-step implementation leads to different
2423 results than hardware single-stepping in one situation: when stepping
2424 into delivering a signal which has an associated signal handler,
2425 hardware single-step will stop at the first instruction of the handler,
2426 while software single-step will simply skip execution of the handler.
2428 For now, this difference in behavior is accepted since there is no
2429 easy way to actually implement single-stepping into a signal handler
2430 without kernel support.
2432 However, there is one scenario where this difference leads to follow-on
2433 problems: if we're stepping off a breakpoint by removing all breakpoints
2434 and then single-stepping. In this case, the software single-step
2435 behavior means that even if there is a *breakpoint* in the signal
2436 handler, GDB still would not stop.
2438 Fortunately, we can at least fix this particular issue. We detect
2439 here the case where we are about to deliver a signal while software
2440 single-stepping with breakpoints removed. In this situation, we
2441 revert the decisions to remove all breakpoints and insert single-
2442 step breakpoints, and instead we install a step-resume breakpoint
2443 at the current address, deliver the signal without stepping, and
2444 once we arrive back at the step-resume breakpoint, actually step
2445 over the breakpoint we originally wanted to step over. */
2446 if (thread_has_single_step_breakpoints_set (tp
)
2447 && sig
!= GDB_SIGNAL_0
2448 && step_over_info_valid_p ())
2450 /* If we have nested signals or a pending signal is delivered
2451 immediately after a handler returns, might already have
2452 a step-resume breakpoint set on the earlier handler. We cannot
2453 set another step-resume breakpoint; just continue on until the
2454 original breakpoint is hit. */
2455 if (tp
->control
.step_resume_breakpoint
== NULL
)
2457 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2458 tp
->step_after_step_resume_breakpoint
= 1;
2461 delete_single_step_breakpoints (tp
);
2463 clear_step_over_info ();
2464 tp
->control
.trap_expected
= 0;
2466 insert_breakpoints ();
2469 /* If STEP is set, it's a request to use hardware stepping
2470 facilities. But in that case, we should never
2471 use singlestep breakpoint. */
2472 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2474 /* Decide the set of threads to ask the target to resume. */
2475 if (tp
->control
.trap_expected
)
2477 /* We're allowing a thread to run past a breakpoint it has
2478 hit, either by single-stepping the thread with the breakpoint
2479 removed, or by displaced stepping, with the breakpoint inserted.
2480 In the former case, we need to single-step only this thread,
2481 and keep others stopped, as they can miss this breakpoint if
2482 allowed to run. That's not really a problem for displaced
2483 stepping, but, we still keep other threads stopped, in case
2484 another thread is also stopped for a breakpoint waiting for
2485 its turn in the displaced stepping queue. */
2486 resume_ptid
= inferior_ptid
;
2489 resume_ptid
= internal_resume_ptid (user_step
);
2491 if (execution_direction
!= EXEC_REVERSE
2492 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2494 /* There are two cases where we currently need to step a
2495 breakpoint instruction when we have a signal to deliver:
2497 - See handle_signal_stop where we handle random signals that
2498 could take out us out of the stepping range. Normally, in
2499 that case we end up continuing (instead of stepping) over the
2500 signal handler with a breakpoint at PC, but there are cases
2501 where we should _always_ single-step, even if we have a
2502 step-resume breakpoint, like when a software watchpoint is
2503 set. Assuming single-stepping and delivering a signal at the
2504 same time would takes us to the signal handler, then we could
2505 have removed the breakpoint at PC to step over it. However,
2506 some hardware step targets (like e.g., Mac OS) can't step
2507 into signal handlers, and for those, we need to leave the
2508 breakpoint at PC inserted, as otherwise if the handler
2509 recurses and executes PC again, it'll miss the breakpoint.
2510 So we leave the breakpoint inserted anyway, but we need to
2511 record that we tried to step a breakpoint instruction, so
2512 that adjust_pc_after_break doesn't end up confused.
2514 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2515 in one thread after another thread that was stepping had been
2516 momentarily paused for a step-over. When we re-resume the
2517 stepping thread, it may be resumed from that address with a
2518 breakpoint that hasn't trapped yet. Seen with
2519 gdb.threads/non-stop-fair-events.exp, on targets that don't
2520 do displaced stepping. */
2522 infrun_debug_printf ("resume: [%s] stepped breakpoint",
2523 target_pid_to_str (tp
->ptid
).c_str ());
2525 tp
->stepped_breakpoint
= 1;
2527 /* Most targets can step a breakpoint instruction, thus
2528 executing it normally. But if this one cannot, just
2529 continue and we will hit it anyway. */
2530 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2535 && tp
->control
.trap_expected
2536 && use_displaced_stepping (tp
)
2537 && !step_over_info_valid_p ())
2539 struct regcache
*resume_regcache
= get_thread_regcache (tp
);
2540 struct gdbarch
*resume_gdbarch
= resume_regcache
->arch ();
2541 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2544 read_memory (actual_pc
, buf
, sizeof (buf
));
2545 displaced_debug_printf ("run %s: %s",
2546 paddress (resume_gdbarch
, actual_pc
),
2547 displaced_step_dump_bytes
2548 (buf
, sizeof (buf
)).c_str ());
2551 if (tp
->control
.may_range_step
)
2553 /* If we're resuming a thread with the PC out of the step
2554 range, then we're doing some nested/finer run control
2555 operation, like stepping the thread out of the dynamic
2556 linker or the displaced stepping scratch pad. We
2557 shouldn't have allowed a range step then. */
2558 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2561 do_target_resume (resume_ptid
, step
, sig
);
2565 /* Resume the inferior. SIG is the signal to give the inferior
2566 (GDB_SIGNAL_0 for none). This is a wrapper around 'resume_1' that
2567 rolls back state on error. */
2570 resume (gdb_signal sig
)
2576 catch (const gdb_exception
&ex
)
2578 /* If resuming is being aborted for any reason, delete any
2579 single-step breakpoint resume_1 may have created, to avoid
2580 confusing the following resumption, and to avoid leaving
2581 single-step breakpoints perturbing other threads, in case
2582 we're running in non-stop mode. */
2583 if (inferior_ptid
!= null_ptid
)
2584 delete_single_step_breakpoints (inferior_thread ());
2594 /* Counter that tracks number of user visible stops. This can be used
2595 to tell whether a command has proceeded the inferior past the
2596 current location. This allows e.g., inferior function calls in
2597 breakpoint commands to not interrupt the command list. When the
2598 call finishes successfully, the inferior is standing at the same
2599 breakpoint as if nothing happened (and so we don't call
2601 static ULONGEST current_stop_id
;
2608 return current_stop_id
;
2611 /* Called when we report a user visible stop. */
2619 /* Clear out all variables saying what to do when inferior is continued.
2620 First do this, then set the ones you want, then call `proceed'. */
2623 clear_proceed_status_thread (struct thread_info
*tp
)
2625 infrun_debug_printf ("%s", target_pid_to_str (tp
->ptid
).c_str ());
2627 /* If we're starting a new sequence, then the previous finished
2628 single-step is no longer relevant. */
2629 if (tp
->suspend
.waitstatus_pending_p
)
2631 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
2633 infrun_debug_printf ("pending event of %s was a finished step. "
2635 target_pid_to_str (tp
->ptid
).c_str ());
2637 tp
->suspend
.waitstatus_pending_p
= 0;
2638 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2643 ("thread %s has pending wait status %s (currently_stepping=%d).",
2644 target_pid_to_str (tp
->ptid
).c_str (),
2645 target_waitstatus_to_string (&tp
->suspend
.waitstatus
).c_str (),
2646 currently_stepping (tp
));
2650 /* If this signal should not be seen by program, give it zero.
2651 Used for debugging signals. */
2652 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2653 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2655 delete tp
->thread_fsm
;
2656 tp
->thread_fsm
= NULL
;
2658 tp
->control
.trap_expected
= 0;
2659 tp
->control
.step_range_start
= 0;
2660 tp
->control
.step_range_end
= 0;
2661 tp
->control
.may_range_step
= 0;
2662 tp
->control
.step_frame_id
= null_frame_id
;
2663 tp
->control
.step_stack_frame_id
= null_frame_id
;
2664 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2665 tp
->control
.step_start_function
= NULL
;
2666 tp
->stop_requested
= 0;
2668 tp
->control
.stop_step
= 0;
2670 tp
->control
.proceed_to_finish
= 0;
2672 tp
->control
.stepping_command
= 0;
2674 /* Discard any remaining commands or status from previous stop. */
2675 bpstat_clear (&tp
->control
.stop_bpstat
);
2679 clear_proceed_status (int step
)
2681 /* With scheduler-locking replay, stop replaying other threads if we're
2682 not replaying the user-visible resume ptid.
2684 This is a convenience feature to not require the user to explicitly
2685 stop replaying the other threads. We're assuming that the user's
2686 intent is to resume tracing the recorded process. */
2687 if (!non_stop
&& scheduler_mode
== schedlock_replay
2688 && target_record_is_replaying (minus_one_ptid
)
2689 && !target_record_will_replay (user_visible_resume_ptid (step
),
2690 execution_direction
))
2691 target_record_stop_replaying ();
2693 if (!non_stop
&& inferior_ptid
!= null_ptid
)
2695 ptid_t resume_ptid
= user_visible_resume_ptid (step
);
2696 process_stratum_target
*resume_target
2697 = user_visible_resume_target (resume_ptid
);
2699 /* In all-stop mode, delete the per-thread status of all threads
2700 we're about to resume, implicitly and explicitly. */
2701 for (thread_info
*tp
: all_non_exited_threads (resume_target
, resume_ptid
))
2702 clear_proceed_status_thread (tp
);
2705 if (inferior_ptid
!= null_ptid
)
2707 struct inferior
*inferior
;
2711 /* If in non-stop mode, only delete the per-thread status of
2712 the current thread. */
2713 clear_proceed_status_thread (inferior_thread ());
2716 inferior
= current_inferior ();
2717 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2720 gdb::observers::about_to_proceed
.notify ();
2723 /* Returns true if TP is still stopped at a breakpoint that needs
2724 stepping-over in order to make progress. If the breakpoint is gone
2725 meanwhile, we can skip the whole step-over dance. */
2728 thread_still_needs_step_over_bp (struct thread_info
*tp
)
2730 if (tp
->stepping_over_breakpoint
)
2732 struct regcache
*regcache
= get_thread_regcache (tp
);
2734 if (breakpoint_here_p (regcache
->aspace (),
2735 regcache_read_pc (regcache
))
2736 == ordinary_breakpoint_here
)
2739 tp
->stepping_over_breakpoint
= 0;
2745 /* Check whether thread TP still needs to start a step-over in order
2746 to make progress when resumed. Returns an bitwise or of enum
2747 step_over_what bits, indicating what needs to be stepped over. */
2749 static step_over_what
2750 thread_still_needs_step_over (struct thread_info
*tp
)
2752 step_over_what what
= 0;
2754 if (thread_still_needs_step_over_bp (tp
))
2755 what
|= STEP_OVER_BREAKPOINT
;
2757 if (tp
->stepping_over_watchpoint
2758 && !target_have_steppable_watchpoint ())
2759 what
|= STEP_OVER_WATCHPOINT
;
2764 /* Returns true if scheduler locking applies. STEP indicates whether
2765 we're about to do a step/next-like command to a thread. */
2768 schedlock_applies (struct thread_info
*tp
)
2770 return (scheduler_mode
== schedlock_on
2771 || (scheduler_mode
== schedlock_step
2772 && tp
->control
.stepping_command
)
2773 || (scheduler_mode
== schedlock_replay
2774 && target_record_will_replay (minus_one_ptid
,
2775 execution_direction
)));
2778 /* Set process_stratum_target::COMMIT_RESUMED_STATE in all target
2779 stacks that have threads executing and don't have threads with
2783 maybe_set_commit_resumed_all_targets ()
2785 scoped_restore_current_thread restore_thread
;
2787 for (inferior
*inf
: all_non_exited_inferiors ())
2789 process_stratum_target
*proc_target
= inf
->process_target ();
2791 if (proc_target
->commit_resumed_state
)
2793 /* We already set this in a previous iteration, via another
2794 inferior sharing the process_stratum target. */
2798 /* If the target has no resumed threads, it would be useless to
2799 ask it to commit the resumed threads. */
2800 if (!proc_target
->threads_executing
)
2802 infrun_debug_printf ("not requesting commit-resumed for target "
2803 "%s, no resumed threads",
2804 proc_target
->shortname ());
2808 /* As an optimization, if a thread from this target has some
2809 status to report, handle it before requiring the target to
2810 commit its resumed threads: handling the status might lead to
2811 resuming more threads. */
2812 bool has_thread_with_pending_status
= false;
2813 for (thread_info
*thread
: all_non_exited_threads (proc_target
))
2814 if (thread
->resumed
&& thread
->suspend
.waitstatus_pending_p
)
2816 has_thread_with_pending_status
= true;
2820 if (has_thread_with_pending_status
)
2822 infrun_debug_printf ("not requesting commit-resumed for target %s, a"
2823 " thread has a pending waitstatus",
2824 proc_target
->shortname ());
2828 switch_to_inferior_no_thread (inf
);
2830 if (target_has_pending_events ())
2832 infrun_debug_printf ("not requesting commit-resumed for target %s, "
2833 "target has pending events",
2834 proc_target
->shortname ());
2838 infrun_debug_printf ("enabling commit-resumed for target %s",
2839 proc_target
->shortname ());
2841 proc_target
->commit_resumed_state
= true;
2848 maybe_call_commit_resumed_all_targets ()
2850 scoped_restore_current_thread restore_thread
;
2852 for (inferior
*inf
: all_non_exited_inferiors ())
2854 process_stratum_target
*proc_target
= inf
->process_target ();
2856 if (!proc_target
->commit_resumed_state
)
2859 switch_to_inferior_no_thread (inf
);
2861 infrun_debug_printf ("calling commit_resumed for target %s",
2862 proc_target
->shortname());
2864 target_commit_resumed ();
2868 /* To track nesting of scoped_disable_commit_resumed objects, ensuring
2869 that only the outermost one attempts to re-enable
2871 static bool enable_commit_resumed
= true;
2875 scoped_disable_commit_resumed::scoped_disable_commit_resumed
2876 (const char *reason
)
2877 : m_reason (reason
),
2878 m_prev_enable_commit_resumed (enable_commit_resumed
)
2880 infrun_debug_printf ("reason=%s", m_reason
);
2882 enable_commit_resumed
= false;
2884 for (inferior
*inf
: all_non_exited_inferiors ())
2886 process_stratum_target
*proc_target
= inf
->process_target ();
2888 if (m_prev_enable_commit_resumed
)
2890 /* This is the outermost instance: force all
2891 COMMIT_RESUMED_STATE to false. */
2892 proc_target
->commit_resumed_state
= false;
2896 /* This is not the outermost instance, we expect
2897 COMMIT_RESUMED_STATE to have been cleared by the
2898 outermost instance. */
2899 gdb_assert (!proc_target
->commit_resumed_state
);
2907 scoped_disable_commit_resumed::reset ()
2913 infrun_debug_printf ("reason=%s", m_reason
);
2915 gdb_assert (!enable_commit_resumed
);
2917 enable_commit_resumed
= m_prev_enable_commit_resumed
;
2919 if (m_prev_enable_commit_resumed
)
2921 /* This is the outermost instance, re-enable
2922 COMMIT_RESUMED_STATE on the targets where it's possible. */
2923 maybe_set_commit_resumed_all_targets ();
2927 /* This is not the outermost instance, we expect
2928 COMMIT_RESUMED_STATE to still be false. */
2929 for (inferior
*inf
: all_non_exited_inferiors ())
2931 process_stratum_target
*proc_target
= inf
->process_target ();
2932 gdb_assert (!proc_target
->commit_resumed_state
);
2939 scoped_disable_commit_resumed::~scoped_disable_commit_resumed ()
2947 scoped_disable_commit_resumed::reset_and_commit ()
2950 maybe_call_commit_resumed_all_targets ();
2955 scoped_enable_commit_resumed::scoped_enable_commit_resumed
2956 (const char *reason
)
2957 : m_reason (reason
),
2958 m_prev_enable_commit_resumed (enable_commit_resumed
)
2960 infrun_debug_printf ("reason=%s", m_reason
);
2962 if (!enable_commit_resumed
)
2964 enable_commit_resumed
= true;
2966 /* Re-enable COMMIT_RESUMED_STATE on the targets where it's
2968 maybe_set_commit_resumed_all_targets ();
2970 maybe_call_commit_resumed_all_targets ();
2976 scoped_enable_commit_resumed::~scoped_enable_commit_resumed ()
2978 infrun_debug_printf ("reason=%s", m_reason
);
2980 gdb_assert (enable_commit_resumed
);
2982 enable_commit_resumed
= m_prev_enable_commit_resumed
;
2984 if (!enable_commit_resumed
)
2986 /* Force all COMMIT_RESUMED_STATE back to false. */
2987 for (inferior
*inf
: all_non_exited_inferiors ())
2989 process_stratum_target
*proc_target
= inf
->process_target ();
2990 proc_target
->commit_resumed_state
= false;
2995 /* Check that all the targets we're about to resume are in non-stop
2996 mode. Ideally, we'd only care whether all targets support
2997 target-async, but we're not there yet. E.g., stop_all_threads
2998 doesn't know how to handle all-stop targets. Also, the remote
2999 protocol in all-stop mode is synchronous, irrespective of
3000 target-async, which means that things like a breakpoint re-set
3001 triggered by one target would try to read memory from all targets
3005 check_multi_target_resumption (process_stratum_target
*resume_target
)
3007 if (!non_stop
&& resume_target
== nullptr)
3009 scoped_restore_current_thread restore_thread
;
3011 /* This is used to track whether we're resuming more than one
3013 process_stratum_target
*first_connection
= nullptr;
3015 /* The first inferior we see with a target that does not work in
3016 always-non-stop mode. */
3017 inferior
*first_not_non_stop
= nullptr;
3019 for (inferior
*inf
: all_non_exited_inferiors ())
3021 switch_to_inferior_no_thread (inf
);
3023 if (!target_has_execution ())
3026 process_stratum_target
*proc_target
3027 = current_inferior ()->process_target();
3029 if (!target_is_non_stop_p ())
3030 first_not_non_stop
= inf
;
3032 if (first_connection
== nullptr)
3033 first_connection
= proc_target
;
3034 else if (first_connection
!= proc_target
3035 && first_not_non_stop
!= nullptr)
3037 switch_to_inferior_no_thread (first_not_non_stop
);
3039 proc_target
= current_inferior ()->process_target();
3041 error (_("Connection %d (%s) does not support "
3042 "multi-target resumption."),
3043 proc_target
->connection_number
,
3044 make_target_connection_string (proc_target
).c_str ());
3050 /* Basic routine for continuing the program in various fashions.
3052 ADDR is the address to resume at, or -1 for resume where stopped.
3053 SIGGNAL is the signal to give it, or GDB_SIGNAL_0 for none,
3054 or GDB_SIGNAL_DEFAULT for act according to how it stopped.
3056 You should call clear_proceed_status before calling proceed. */
3059 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
)
3061 INFRUN_SCOPED_DEBUG_ENTER_EXIT
;
3063 struct regcache
*regcache
;
3064 struct gdbarch
*gdbarch
;
3066 struct execution_control_state ecss
;
3067 struct execution_control_state
*ecs
= &ecss
;
3070 /* If we're stopped at a fork/vfork, follow the branch set by the
3071 "set follow-fork-mode" command; otherwise, we'll just proceed
3072 resuming the current thread. */
3073 if (!follow_fork ())
3075 /* The target for some reason decided not to resume. */
3077 if (target_can_async_p ())
3078 inferior_event_handler (INF_EXEC_COMPLETE
);
3082 /* We'll update this if & when we switch to a new thread. */
3083 previous_inferior_ptid
= inferior_ptid
;
3085 regcache
= get_current_regcache ();
3086 gdbarch
= regcache
->arch ();
3087 const address_space
*aspace
= regcache
->aspace ();
3089 pc
= regcache_read_pc_protected (regcache
);
3091 thread_info
*cur_thr
= inferior_thread ();
3093 /* Fill in with reasonable starting values. */
3094 init_thread_stepping_state (cur_thr
);
3096 gdb_assert (!thread_is_in_step_over_chain (cur_thr
));
3099 = user_visible_resume_ptid (cur_thr
->control
.stepping_command
);
3100 process_stratum_target
*resume_target
3101 = user_visible_resume_target (resume_ptid
);
3103 check_multi_target_resumption (resume_target
);
3105 if (addr
== (CORE_ADDR
) -1)
3107 if (pc
== cur_thr
->suspend
.stop_pc
3108 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
3109 && execution_direction
!= EXEC_REVERSE
)
3110 /* There is a breakpoint at the address we will resume at,
3111 step one instruction before inserting breakpoints so that
3112 we do not stop right away (and report a second hit at this
3115 Note, we don't do this in reverse, because we won't
3116 actually be executing the breakpoint insn anyway.
3117 We'll be (un-)executing the previous instruction. */
3118 cur_thr
->stepping_over_breakpoint
= 1;
3119 else if (gdbarch_single_step_through_delay_p (gdbarch
)
3120 && gdbarch_single_step_through_delay (gdbarch
,
3121 get_current_frame ()))
3122 /* We stepped onto an instruction that needs to be stepped
3123 again before re-inserting the breakpoint, do so. */
3124 cur_thr
->stepping_over_breakpoint
= 1;
3128 regcache_write_pc (regcache
, addr
);
3131 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
3132 cur_thr
->suspend
.stop_signal
= siggnal
;
3134 /* If an exception is thrown from this point on, make sure to
3135 propagate GDB's knowledge of the executing state to the
3136 frontend/user running state. */
3137 scoped_finish_thread_state
finish_state (resume_target
, resume_ptid
);
3139 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
3140 threads (e.g., we might need to set threads stepping over
3141 breakpoints first), from the user/frontend's point of view, all
3142 threads in RESUME_PTID are now running. Unless we're calling an
3143 inferior function, as in that case we pretend the inferior
3144 doesn't run at all. */
3145 if (!cur_thr
->control
.in_infcall
)
3146 set_running (resume_target
, resume_ptid
, true);
3148 infrun_debug_printf ("addr=%s, signal=%s", paddress (gdbarch
, addr
),
3149 gdb_signal_to_symbol_string (siggnal
));
3151 annotate_starting ();
3153 /* Make sure that output from GDB appears before output from the
3155 gdb_flush (gdb_stdout
);
3157 /* Since we've marked the inferior running, give it the terminal. A
3158 QUIT/Ctrl-C from here on is forwarded to the target (which can
3159 still detect attempts to unblock a stuck connection with repeated
3160 Ctrl-C from within target_pass_ctrlc). */
3161 target_terminal::inferior ();
3163 /* In a multi-threaded task we may select another thread and
3164 then continue or step.
3166 But if a thread that we're resuming had stopped at a breakpoint,
3167 it will immediately cause another breakpoint stop without any
3168 execution (i.e. it will report a breakpoint hit incorrectly). So
3169 we must step over it first.
3171 Look for threads other than the current (TP) that reported a
3172 breakpoint hit and haven't been resumed yet since. */
3174 /* If scheduler locking applies, we can avoid iterating over all
3176 if (!non_stop
&& !schedlock_applies (cur_thr
))
3178 for (thread_info
*tp
: all_non_exited_threads (resume_target
,
3181 switch_to_thread_no_regs (tp
);
3183 /* Ignore the current thread here. It's handled
3188 if (!thread_still_needs_step_over (tp
))
3191 gdb_assert (!thread_is_in_step_over_chain (tp
));
3193 infrun_debug_printf ("need to step-over [%s] first",
3194 target_pid_to_str (tp
->ptid
).c_str ());
3196 global_thread_step_over_chain_enqueue (tp
);
3199 switch_to_thread (cur_thr
);
3202 /* Enqueue the current thread last, so that we move all other
3203 threads over their breakpoints first. */
3204 if (cur_thr
->stepping_over_breakpoint
)
3205 global_thread_step_over_chain_enqueue (cur_thr
);
3207 /* If the thread isn't started, we'll still need to set its prev_pc,
3208 so that switch_back_to_stepped_thread knows the thread hasn't
3209 advanced. Must do this before resuming any thread, as in
3210 all-stop/remote, once we resume we can't send any other packet
3211 until the target stops again. */
3212 cur_thr
->prev_pc
= regcache_read_pc_protected (regcache
);
3215 scoped_disable_commit_resumed
disable_commit_resumed ("proceeding");
3217 started
= start_step_over ();
3219 if (step_over_info_valid_p ())
3221 /* Either this thread started a new in-line step over, or some
3222 other thread was already doing one. In either case, don't
3223 resume anything else until the step-over is finished. */
3225 else if (started
&& !target_is_non_stop_p ())
3227 /* A new displaced stepping sequence was started. In all-stop,
3228 we can't talk to the target anymore until it next stops. */
3230 else if (!non_stop
&& target_is_non_stop_p ())
3232 INFRUN_SCOPED_DEBUG_START_END
3233 ("resuming threads, all-stop-on-top-of-non-stop");
3235 /* In all-stop, but the target is always in non-stop mode.
3236 Start all other threads that are implicitly resumed too. */
3237 for (thread_info
*tp
: all_non_exited_threads (resume_target
,
3240 switch_to_thread_no_regs (tp
);
3242 if (!tp
->inf
->has_execution ())
3244 infrun_debug_printf ("[%s] target has no execution",
3245 target_pid_to_str (tp
->ptid
).c_str ());
3251 infrun_debug_printf ("[%s] resumed",
3252 target_pid_to_str (tp
->ptid
).c_str ());
3253 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
3257 if (thread_is_in_step_over_chain (tp
))
3259 infrun_debug_printf ("[%s] needs step-over",
3260 target_pid_to_str (tp
->ptid
).c_str ());
3264 infrun_debug_printf ("resuming %s",
3265 target_pid_to_str (tp
->ptid
).c_str ());
3267 reset_ecs (ecs
, tp
);
3268 switch_to_thread (tp
);
3269 keep_going_pass_signal (ecs
);
3270 if (!ecs
->wait_some_more
)
3271 error (_("Command aborted."));
3274 else if (!cur_thr
->resumed
&& !thread_is_in_step_over_chain (cur_thr
))
3276 /* The thread wasn't started, and isn't queued, run it now. */
3277 reset_ecs (ecs
, cur_thr
);
3278 switch_to_thread (cur_thr
);
3279 keep_going_pass_signal (ecs
);
3280 if (!ecs
->wait_some_more
)
3281 error (_("Command aborted."));
3284 disable_commit_resumed
.reset_and_commit ();
3287 finish_state
.release ();
3289 /* If we've switched threads above, switch back to the previously
3290 current thread. We don't want the user to see a different
3292 switch_to_thread (cur_thr
);
3294 /* Tell the event loop to wait for it to stop. If the target
3295 supports asynchronous execution, it'll do this from within
3297 if (!target_can_async_p ())
3298 mark_async_event_handler (infrun_async_inferior_event_token
);
3302 /* Start remote-debugging of a machine over a serial link. */
3305 start_remote (int from_tty
)
3307 inferior
*inf
= current_inferior ();
3308 inf
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
3310 /* Always go on waiting for the target, regardless of the mode. */
3311 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3312 indicate to wait_for_inferior that a target should timeout if
3313 nothing is returned (instead of just blocking). Because of this,
3314 targets expecting an immediate response need to, internally, set
3315 things up so that the target_wait() is forced to eventually
3317 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3318 differentiate to its caller what the state of the target is after
3319 the initial open has been performed. Here we're assuming that
3320 the target has stopped. It should be possible to eventually have
3321 target_open() return to the caller an indication that the target
3322 is currently running and GDB state should be set to the same as
3323 for an async run. */
3324 wait_for_inferior (inf
);
3326 /* Now that the inferior has stopped, do any bookkeeping like
3327 loading shared libraries. We want to do this before normal_stop,
3328 so that the displayed frame is up to date. */
3329 post_create_inferior (from_tty
);
3334 /* Initialize static vars when a new inferior begins. */
3337 init_wait_for_inferior (void)
3339 /* These are meaningless until the first time through wait_for_inferior. */
3341 breakpoint_init_inferior (inf_starting
);
3343 clear_proceed_status (0);
3345 nullify_last_target_wait_ptid ();
3347 previous_inferior_ptid
= inferior_ptid
;
3352 static void handle_inferior_event (struct execution_control_state
*ecs
);
3354 static void handle_step_into_function (struct gdbarch
*gdbarch
,
3355 struct execution_control_state
*ecs
);
3356 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
3357 struct execution_control_state
*ecs
);
3358 static void handle_signal_stop (struct execution_control_state
*ecs
);
3359 static void check_exception_resume (struct execution_control_state
*,
3360 struct frame_info
*);
3362 static void end_stepping_range (struct execution_control_state
*ecs
);
3363 static void stop_waiting (struct execution_control_state
*ecs
);
3364 static void keep_going (struct execution_control_state
*ecs
);
3365 static void process_event_stop_test (struct execution_control_state
*ecs
);
3366 static bool switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
3368 /* This function is attached as a "thread_stop_requested" observer.
3369 Cleanup local state that assumed the PTID was to be resumed, and
3370 report the stop to the frontend. */
3373 infrun_thread_stop_requested (ptid_t ptid
)
3375 process_stratum_target
*curr_target
= current_inferior ()->process_target ();
3377 /* PTID was requested to stop. If the thread was already stopped,
3378 but the user/frontend doesn't know about that yet (e.g., the
3379 thread had been temporarily paused for some step-over), set up
3380 for reporting the stop now. */
3381 for (thread_info
*tp
: all_threads (curr_target
, ptid
))
3383 if (tp
->state
!= THREAD_RUNNING
)
3388 /* Remove matching threads from the step-over queue, so
3389 start_step_over doesn't try to resume them
3391 if (thread_is_in_step_over_chain (tp
))
3392 global_thread_step_over_chain_remove (tp
);
3394 /* If the thread is stopped, but the user/frontend doesn't
3395 know about that yet, queue a pending event, as if the
3396 thread had just stopped now. Unless the thread already had
3398 if (!tp
->suspend
.waitstatus_pending_p
)
3400 tp
->suspend
.waitstatus_pending_p
= 1;
3401 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_STOPPED
;
3402 tp
->suspend
.waitstatus
.value
.sig
= GDB_SIGNAL_0
;
3405 /* Clear the inline-frame state, since we're re-processing the
3407 clear_inline_frame_state (tp
);
3409 /* If this thread was paused because some other thread was
3410 doing an inline-step over, let that finish first. Once
3411 that happens, we'll restart all threads and consume pending
3412 stop events then. */
3413 if (step_over_info_valid_p ())
3416 /* Otherwise we can process the (new) pending event now. Set
3417 it so this pending event is considered by
3424 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
3426 if (target_last_proc_target
== tp
->inf
->process_target ()
3427 && target_last_wait_ptid
== tp
->ptid
)
3428 nullify_last_target_wait_ptid ();
3431 /* Delete the step resume, single-step and longjmp/exception resume
3432 breakpoints of TP. */
3435 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
3437 delete_step_resume_breakpoint (tp
);
3438 delete_exception_resume_breakpoint (tp
);
3439 delete_single_step_breakpoints (tp
);
3442 /* If the target still has execution, call FUNC for each thread that
3443 just stopped. In all-stop, that's all the non-exited threads; in
3444 non-stop, that's the current thread, only. */
3446 typedef void (*for_each_just_stopped_thread_callback_func
)
3447 (struct thread_info
*tp
);
3450 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
3452 if (!target_has_execution () || inferior_ptid
== null_ptid
)
3455 if (target_is_non_stop_p ())
3457 /* If in non-stop mode, only the current thread stopped. */
3458 func (inferior_thread ());
3462 /* In all-stop mode, all threads have stopped. */
3463 for (thread_info
*tp
: all_non_exited_threads ())
3468 /* Delete the step resume and longjmp/exception resume breakpoints of
3469 the threads that just stopped. */
3472 delete_just_stopped_threads_infrun_breakpoints (void)
3474 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3477 /* Delete the single-step breakpoints of the threads that just
3481 delete_just_stopped_threads_single_step_breakpoints (void)
3483 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3489 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3490 const struct target_waitstatus
*ws
)
3492 infrun_debug_printf ("target_wait (%d.%ld.%ld [%s], status) =",
3496 target_pid_to_str (waiton_ptid
).c_str ());
3497 infrun_debug_printf (" %d.%ld.%ld [%s],",
3501 target_pid_to_str (result_ptid
).c_str ());
3502 infrun_debug_printf (" %s", target_waitstatus_to_string (ws
).c_str ());
3505 /* Select a thread at random, out of those which are resumed and have
3508 static struct thread_info
*
3509 random_pending_event_thread (inferior
*inf
, ptid_t waiton_ptid
)
3513 auto has_event
= [&] (thread_info
*tp
)
3515 return (tp
->ptid
.matches (waiton_ptid
)
3517 && tp
->suspend
.waitstatus_pending_p
);
3520 /* First see how many events we have. Count only resumed threads
3521 that have an event pending. */
3522 for (thread_info
*tp
: inf
->non_exited_threads ())
3526 if (num_events
== 0)
3529 /* Now randomly pick a thread out of those that have had events. */
3530 int random_selector
= (int) ((num_events
* (double) rand ())
3531 / (RAND_MAX
+ 1.0));
3534 infrun_debug_printf ("Found %d events, selecting #%d",
3535 num_events
, random_selector
);
3537 /* Select the Nth thread that has had an event. */
3538 for (thread_info
*tp
: inf
->non_exited_threads ())
3540 if (random_selector
-- == 0)
3543 gdb_assert_not_reached ("event thread not found");
3546 /* Wrapper for target_wait that first checks whether threads have
3547 pending statuses to report before actually asking the target for
3548 more events. INF is the inferior we're using to call target_wait
3552 do_target_wait_1 (inferior
*inf
, ptid_t ptid
,
3553 target_waitstatus
*status
, target_wait_flags options
)
3556 struct thread_info
*tp
;
3558 /* We know that we are looking for an event in the target of inferior
3559 INF, but we don't know which thread the event might come from. As
3560 such we want to make sure that INFERIOR_PTID is reset so that none of
3561 the wait code relies on it - doing so is always a mistake. */
3562 switch_to_inferior_no_thread (inf
);
3564 /* First check if there is a resumed thread with a wait status
3566 if (ptid
== minus_one_ptid
|| ptid
.is_pid ())
3568 tp
= random_pending_event_thread (inf
, ptid
);
3572 infrun_debug_printf ("Waiting for specific thread %s.",
3573 target_pid_to_str (ptid
).c_str ());
3575 /* We have a specific thread to check. */
3576 tp
= find_thread_ptid (inf
, ptid
);
3577 gdb_assert (tp
!= NULL
);
3578 if (!tp
->suspend
.waitstatus_pending_p
)
3583 && (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3584 || tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
3586 struct regcache
*regcache
= get_thread_regcache (tp
);
3587 struct gdbarch
*gdbarch
= regcache
->arch ();
3591 pc
= regcache_read_pc (regcache
);
3593 if (pc
!= tp
->suspend
.stop_pc
)
3595 infrun_debug_printf ("PC of %s changed. was=%s, now=%s",
3596 target_pid_to_str (tp
->ptid
).c_str (),
3597 paddress (gdbarch
, tp
->suspend
.stop_pc
),
3598 paddress (gdbarch
, pc
));
3601 else if (!breakpoint_inserted_here_p (regcache
->aspace (), pc
))
3603 infrun_debug_printf ("previous breakpoint of %s, at %s gone",
3604 target_pid_to_str (tp
->ptid
).c_str (),
3605 paddress (gdbarch
, pc
));
3612 infrun_debug_printf ("pending event of %s cancelled.",
3613 target_pid_to_str (tp
->ptid
).c_str ());
3615 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_SPURIOUS
;
3616 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3622 infrun_debug_printf ("Using pending wait status %s for %s.",
3623 target_waitstatus_to_string
3624 (&tp
->suspend
.waitstatus
).c_str (),
3625 target_pid_to_str (tp
->ptid
).c_str ());
3627 /* Now that we've selected our final event LWP, un-adjust its PC
3628 if it was a software breakpoint (and the target doesn't
3629 always adjust the PC itself). */
3630 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3631 && !target_supports_stopped_by_sw_breakpoint ())
3633 struct regcache
*regcache
;
3634 struct gdbarch
*gdbarch
;
3637 regcache
= get_thread_regcache (tp
);
3638 gdbarch
= regcache
->arch ();
3640 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3645 pc
= regcache_read_pc (regcache
);
3646 regcache_write_pc (regcache
, pc
+ decr_pc
);
3650 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3651 *status
= tp
->suspend
.waitstatus
;
3652 tp
->suspend
.waitstatus_pending_p
= 0;
3654 /* Wake up the event loop again, until all pending events are
3656 if (target_is_async_p ())
3657 mark_async_event_handler (infrun_async_inferior_event_token
);
3661 /* But if we don't find one, we'll have to wait. */
3663 /* We can't ask a non-async target to do a non-blocking wait, so this will be
3665 if (!target_can_async_p ())
3666 options
&= ~TARGET_WNOHANG
;
3668 if (deprecated_target_wait_hook
)
3669 event_ptid
= deprecated_target_wait_hook (ptid
, status
, options
);
3671 event_ptid
= target_wait (ptid
, status
, options
);
3676 /* Wrapper for target_wait that first checks whether threads have
3677 pending statuses to report before actually asking the target for
3678 more events. Polls for events from all inferiors/targets. */
3681 do_target_wait (execution_control_state
*ecs
, target_wait_flags options
)
3683 int num_inferiors
= 0;
3684 int random_selector
;
3686 /* For fairness, we pick the first inferior/target to poll at random
3687 out of all inferiors that may report events, and then continue
3688 polling the rest of the inferior list starting from that one in a
3689 circular fashion until the whole list is polled once. */
3691 auto inferior_matches
= [] (inferior
*inf
)
3693 return inf
->process_target () != nullptr;
3696 /* First see how many matching inferiors we have. */
3697 for (inferior
*inf
: all_inferiors ())
3698 if (inferior_matches (inf
))
3701 if (num_inferiors
== 0)
3703 ecs
->ws
.kind
= TARGET_WAITKIND_IGNORE
;
3707 /* Now randomly pick an inferior out of those that matched. */
3708 random_selector
= (int)
3709 ((num_inferiors
* (double) rand ()) / (RAND_MAX
+ 1.0));
3711 if (num_inferiors
> 1)
3712 infrun_debug_printf ("Found %d inferiors, starting at #%d",
3713 num_inferiors
, random_selector
);
3715 /* Select the Nth inferior that matched. */
3717 inferior
*selected
= nullptr;
3719 for (inferior
*inf
: all_inferiors ())
3720 if (inferior_matches (inf
))
3721 if (random_selector
-- == 0)
3727 /* Now poll for events out of each of the matching inferior's
3728 targets, starting from the selected one. */
3730 auto do_wait
= [&] (inferior
*inf
)
3732 ecs
->ptid
= do_target_wait_1 (inf
, minus_one_ptid
, &ecs
->ws
, options
);
3733 ecs
->target
= inf
->process_target ();
3734 return (ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
);
3737 /* Needed in 'all-stop + target-non-stop' mode, because we end up
3738 here spuriously after the target is all stopped and we've already
3739 reported the stop to the user, polling for events. */
3740 scoped_restore_current_thread restore_thread
;
3742 int inf_num
= selected
->num
;
3743 for (inferior
*inf
= selected
; inf
!= NULL
; inf
= inf
->next
)
3744 if (inferior_matches (inf
))
3748 for (inferior
*inf
= inferior_list
;
3749 inf
!= NULL
&& inf
->num
< inf_num
;
3751 if (inferior_matches (inf
))
3755 ecs
->ws
.kind
= TARGET_WAITKIND_IGNORE
;
3759 /* An event reported by wait_one. */
3761 struct wait_one_event
3763 /* The target the event came out of. */
3764 process_stratum_target
*target
;
3766 /* The PTID the event was for. */
3769 /* The waitstatus. */
3770 target_waitstatus ws
;
3773 static bool handle_one (const wait_one_event
&event
);
3774 static void restart_threads (struct thread_info
*event_thread
,
3775 inferior
*inf
= nullptr);
3777 /* Prepare and stabilize the inferior for detaching it. E.g.,
3778 detaching while a thread is displaced stepping is a recipe for
3779 crashing it, as nothing would readjust the PC out of the scratch
3783 prepare_for_detach (void)
3785 struct inferior
*inf
= current_inferior ();
3786 ptid_t pid_ptid
= ptid_t (inf
->pid
);
3787 scoped_restore_current_thread restore_thread
;
3789 scoped_restore restore_detaching
= make_scoped_restore (&inf
->detaching
, true);
3791 /* Remove all threads of INF from the global step-over chain. We
3792 want to stop any ongoing step-over, not start any new one. */
3794 for (thread_info
*tp
= global_thread_step_over_chain_head
;
3798 next
= global_thread_step_over_chain_next (tp
);
3800 global_thread_step_over_chain_remove (tp
);
3803 /* If we were already in the middle of an inline step-over, and the
3804 thread stepping belongs to the inferior we're detaching, we need
3805 to restart the threads of other inferiors. */
3806 if (step_over_info
.thread
!= -1)
3808 infrun_debug_printf ("inline step-over in-process while detaching");
3810 thread_info
*thr
= find_thread_global_id (step_over_info
.thread
);
3811 if (thr
->inf
== inf
)
3813 /* Since we removed threads of INF from the step-over chain,
3814 we know this won't start a step-over for INF. */
3815 clear_step_over_info ();
3817 if (target_is_non_stop_p ())
3819 /* Start a new step-over in another thread if there's
3820 one that needs it. */
3823 /* Restart all other threads (except the
3824 previously-stepping thread, since that one is still
3826 if (!step_over_info_valid_p ())
3827 restart_threads (thr
);
3832 if (displaced_step_in_progress (inf
))
3834 infrun_debug_printf ("displaced-stepping in-process while detaching");
3836 /* Stop threads currently displaced stepping, aborting it. */
3838 for (thread_info
*thr
: inf
->non_exited_threads ())
3840 if (thr
->displaced_step_state
.in_progress ())
3844 if (!thr
->stop_requested
)
3846 target_stop (thr
->ptid
);
3847 thr
->stop_requested
= true;
3851 thr
->resumed
= false;
3855 while (displaced_step_in_progress (inf
))
3857 wait_one_event event
;
3859 event
.target
= inf
->process_target ();
3860 event
.ptid
= do_target_wait_1 (inf
, pid_ptid
, &event
.ws
, 0);
3863 print_target_wait_results (pid_ptid
, event
.ptid
, &event
.ws
);
3868 /* It's OK to leave some of the threads of INF stopped, since
3869 they'll be detached shortly. */
3873 /* Wait for control to return from inferior to debugger.
3875 If inferior gets a signal, we may decide to start it up again
3876 instead of returning. That is why there is a loop in this function.
3877 When this function actually returns it means the inferior
3878 should be left stopped and GDB should read more commands. */
3881 wait_for_inferior (inferior
*inf
)
3883 infrun_debug_printf ("wait_for_inferior ()");
3885 SCOPE_EXIT
{ delete_just_stopped_threads_infrun_breakpoints (); };
3887 /* If an error happens while handling the event, propagate GDB's
3888 knowledge of the executing state to the frontend/user running
3890 scoped_finish_thread_state finish_state
3891 (inf
->process_target (), minus_one_ptid
);
3895 struct execution_control_state ecss
;
3896 struct execution_control_state
*ecs
= &ecss
;
3898 memset (ecs
, 0, sizeof (*ecs
));
3900 overlay_cache_invalid
= 1;
3902 /* Flush target cache before starting to handle each event.
3903 Target was running and cache could be stale. This is just a
3904 heuristic. Running threads may modify target memory, but we
3905 don't get any event. */
3906 target_dcache_invalidate ();
3908 ecs
->ptid
= do_target_wait_1 (inf
, minus_one_ptid
, &ecs
->ws
, 0);
3909 ecs
->target
= inf
->process_target ();
3912 print_target_wait_results (minus_one_ptid
, ecs
->ptid
, &ecs
->ws
);
3914 /* Now figure out what to do with the result of the result. */
3915 handle_inferior_event (ecs
);
3917 if (!ecs
->wait_some_more
)
3921 /* No error, don't finish the state yet. */
3922 finish_state
.release ();
3925 /* Cleanup that reinstalls the readline callback handler, if the
3926 target is running in the background. If while handling the target
3927 event something triggered a secondary prompt, like e.g., a
3928 pagination prompt, we'll have removed the callback handler (see
3929 gdb_readline_wrapper_line). Need to do this as we go back to the
3930 event loop, ready to process further input. Note this has no
3931 effect if the handler hasn't actually been removed, because calling
3932 rl_callback_handler_install resets the line buffer, thus losing
3936 reinstall_readline_callback_handler_cleanup ()
3938 struct ui
*ui
= current_ui
;
3942 /* We're not going back to the top level event loop yet. Don't
3943 install the readline callback, as it'd prep the terminal,
3944 readline-style (raw, noecho) (e.g., --batch). We'll install
3945 it the next time the prompt is displayed, when we're ready
3950 if (ui
->command_editing
&& ui
->prompt_state
!= PROMPT_BLOCKED
)
3951 gdb_rl_callback_handler_reinstall ();
3954 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3955 that's just the event thread. In all-stop, that's all threads. */
3958 clean_up_just_stopped_threads_fsms (struct execution_control_state
*ecs
)
3960 if (ecs
->event_thread
!= NULL
3961 && ecs
->event_thread
->thread_fsm
!= NULL
)
3962 ecs
->event_thread
->thread_fsm
->clean_up (ecs
->event_thread
);
3966 for (thread_info
*thr
: all_non_exited_threads ())
3968 if (thr
->thread_fsm
== NULL
)
3970 if (thr
== ecs
->event_thread
)
3973 switch_to_thread (thr
);
3974 thr
->thread_fsm
->clean_up (thr
);
3977 if (ecs
->event_thread
!= NULL
)
3978 switch_to_thread (ecs
->event_thread
);
3982 /* Helper for all_uis_check_sync_execution_done that works on the
3986 check_curr_ui_sync_execution_done (void)
3988 struct ui
*ui
= current_ui
;
3990 if (ui
->prompt_state
== PROMPT_NEEDED
3992 && !gdb_in_secondary_prompt_p (ui
))
3994 target_terminal::ours ();
3995 gdb::observers::sync_execution_done
.notify ();
3996 ui_register_input_event_handler (ui
);
4003 all_uis_check_sync_execution_done (void)
4005 SWITCH_THRU_ALL_UIS ()
4007 check_curr_ui_sync_execution_done ();
4014 all_uis_on_sync_execution_starting (void)
4016 SWITCH_THRU_ALL_UIS ()
4018 if (current_ui
->prompt_state
== PROMPT_NEEDED
)
4019 async_disable_stdin ();
4023 /* Asynchronous version of wait_for_inferior. It is called by the
4024 event loop whenever a change of state is detected on the file
4025 descriptor corresponding to the target. It can be called more than
4026 once to complete a single execution command. In such cases we need
4027 to keep the state in a global variable ECSS. If it is the last time
4028 that this function is called for a single execution command, then
4029 report to the user that the inferior has stopped, and do the
4030 necessary cleanups. */
4033 fetch_inferior_event ()
4035 INFRUN_SCOPED_DEBUG_ENTER_EXIT
;
4037 struct execution_control_state ecss
;
4038 struct execution_control_state
*ecs
= &ecss
;
4041 memset (ecs
, 0, sizeof (*ecs
));
4043 /* Events are always processed with the main UI as current UI. This
4044 way, warnings, debug output, etc. are always consistently sent to
4045 the main console. */
4046 scoped_restore save_ui
= make_scoped_restore (¤t_ui
, main_ui
);
4048 /* Temporarily disable pagination. Otherwise, the user would be
4049 given an option to press 'q' to quit, which would cause an early
4050 exit and could leave GDB in a half-baked state. */
4051 scoped_restore save_pagination
4052 = make_scoped_restore (&pagination_enabled
, false);
4054 /* End up with readline processing input, if necessary. */
4056 SCOPE_EXIT
{ reinstall_readline_callback_handler_cleanup (); };
4058 /* We're handling a live event, so make sure we're doing live
4059 debugging. If we're looking at traceframes while the target is
4060 running, we're going to need to get back to that mode after
4061 handling the event. */
4062 gdb::optional
<scoped_restore_current_traceframe
> maybe_restore_traceframe
;
4065 maybe_restore_traceframe
.emplace ();
4066 set_current_traceframe (-1);
4069 /* The user/frontend should not notice a thread switch due to
4070 internal events. Make sure we revert to the user selected
4071 thread and frame after handling the event and running any
4072 breakpoint commands. */
4073 scoped_restore_current_thread restore_thread
;
4075 overlay_cache_invalid
= 1;
4076 /* Flush target cache before starting to handle each event. Target
4077 was running and cache could be stale. This is just a heuristic.
4078 Running threads may modify target memory, but we don't get any
4080 target_dcache_invalidate ();
4082 scoped_restore save_exec_dir
4083 = make_scoped_restore (&execution_direction
,
4084 target_execution_direction ());
4086 /* Allow targets to pause their resumed threads while we handle
4088 scoped_disable_commit_resumed
disable_commit_resumed ("handling event");
4090 if (!do_target_wait (ecs
, TARGET_WNOHANG
))
4092 infrun_debug_printf ("do_target_wait returned no event");
4093 disable_commit_resumed
.reset_and_commit ();
4097 gdb_assert (ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
);
4099 /* Switch to the target that generated the event, so we can do
4101 switch_to_target_no_thread (ecs
->target
);
4104 print_target_wait_results (minus_one_ptid
, ecs
->ptid
, &ecs
->ws
);
4106 /* If an error happens while handling the event, propagate GDB's
4107 knowledge of the executing state to the frontend/user running
4109 ptid_t finish_ptid
= !target_is_non_stop_p () ? minus_one_ptid
: ecs
->ptid
;
4110 scoped_finish_thread_state
finish_state (ecs
->target
, finish_ptid
);
4112 /* Get executed before scoped_restore_current_thread above to apply
4113 still for the thread which has thrown the exception. */
4114 auto defer_bpstat_clear
4115 = make_scope_exit (bpstat_clear_actions
);
4116 auto defer_delete_threads
4117 = make_scope_exit (delete_just_stopped_threads_infrun_breakpoints
);
4119 /* Now figure out what to do with the result of the result. */
4120 handle_inferior_event (ecs
);
4122 if (!ecs
->wait_some_more
)
4124 struct inferior
*inf
= find_inferior_ptid (ecs
->target
, ecs
->ptid
);
4125 bool should_stop
= true;
4126 struct thread_info
*thr
= ecs
->event_thread
;
4128 delete_just_stopped_threads_infrun_breakpoints ();
4132 struct thread_fsm
*thread_fsm
= thr
->thread_fsm
;
4134 if (thread_fsm
!= NULL
)
4135 should_stop
= thread_fsm
->should_stop (thr
);
4144 bool should_notify_stop
= true;
4147 clean_up_just_stopped_threads_fsms (ecs
);
4149 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
4150 should_notify_stop
= thr
->thread_fsm
->should_notify_stop ();
4152 if (should_notify_stop
)
4154 /* We may not find an inferior if this was a process exit. */
4155 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
4156 proceeded
= normal_stop ();
4161 inferior_event_handler (INF_EXEC_COMPLETE
);
4165 /* If we got a TARGET_WAITKIND_NO_RESUMED event, then the
4166 previously selected thread is gone. We have two
4167 choices - switch to no thread selected, or restore the
4168 previously selected thread (now exited). We chose the
4169 later, just because that's what GDB used to do. After
4170 this, "info threads" says "The current thread <Thread
4171 ID 2> has terminated." instead of "No thread
4175 && ecs
->ws
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
4176 restore_thread
.dont_restore ();
4180 defer_delete_threads
.release ();
4181 defer_bpstat_clear
.release ();
4183 /* No error, don't finish the thread states yet. */
4184 finish_state
.release ();
4186 disable_commit_resumed
.reset_and_commit ();
4188 /* This scope is used to ensure that readline callbacks are
4189 reinstalled here. */
4192 /* If a UI was in sync execution mode, and now isn't, restore its
4193 prompt (a synchronous execution command has finished, and we're
4194 ready for input). */
4195 all_uis_check_sync_execution_done ();
4198 && exec_done_display_p
4199 && (inferior_ptid
== null_ptid
4200 || inferior_thread ()->state
!= THREAD_RUNNING
))
4201 printf_unfiltered (_("completed.\n"));
4207 set_step_info (thread_info
*tp
, struct frame_info
*frame
,
4208 struct symtab_and_line sal
)
4210 /* This can be removed once this function no longer implicitly relies on the
4211 inferior_ptid value. */
4212 gdb_assert (inferior_ptid
== tp
->ptid
);
4214 tp
->control
.step_frame_id
= get_frame_id (frame
);
4215 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
4217 tp
->current_symtab
= sal
.symtab
;
4218 tp
->current_line
= sal
.line
;
4221 /* Clear context switchable stepping state. */
4224 init_thread_stepping_state (struct thread_info
*tss
)
4226 tss
->stepped_breakpoint
= 0;
4227 tss
->stepping_over_breakpoint
= 0;
4228 tss
->stepping_over_watchpoint
= 0;
4229 tss
->step_after_step_resume_breakpoint
= 0;
4235 set_last_target_status (process_stratum_target
*target
, ptid_t ptid
,
4236 target_waitstatus status
)
4238 target_last_proc_target
= target
;
4239 target_last_wait_ptid
= ptid
;
4240 target_last_waitstatus
= status
;
4246 get_last_target_status (process_stratum_target
**target
, ptid_t
*ptid
,
4247 target_waitstatus
*status
)
4249 if (target
!= nullptr)
4250 *target
= target_last_proc_target
;
4251 if (ptid
!= nullptr)
4252 *ptid
= target_last_wait_ptid
;
4253 if (status
!= nullptr)
4254 *status
= target_last_waitstatus
;
4260 nullify_last_target_wait_ptid (void)
4262 target_last_proc_target
= nullptr;
4263 target_last_wait_ptid
= minus_one_ptid
;
4264 target_last_waitstatus
= {};
4267 /* Switch thread contexts. */
4270 context_switch (execution_control_state
*ecs
)
4272 if (ecs
->ptid
!= inferior_ptid
4273 && (inferior_ptid
== null_ptid
4274 || ecs
->event_thread
!= inferior_thread ()))
4276 infrun_debug_printf ("Switching context from %s to %s",
4277 target_pid_to_str (inferior_ptid
).c_str (),
4278 target_pid_to_str (ecs
->ptid
).c_str ());
4281 switch_to_thread (ecs
->event_thread
);
4284 /* If the target can't tell whether we've hit breakpoints
4285 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
4286 check whether that could have been caused by a breakpoint. If so,
4287 adjust the PC, per gdbarch_decr_pc_after_break. */
4290 adjust_pc_after_break (struct thread_info
*thread
,
4291 struct target_waitstatus
*ws
)
4293 struct regcache
*regcache
;
4294 struct gdbarch
*gdbarch
;
4295 CORE_ADDR breakpoint_pc
, decr_pc
;
4297 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
4298 we aren't, just return.
4300 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
4301 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
4302 implemented by software breakpoints should be handled through the normal
4305 NOTE drow/2004-01-31: On some targets, breakpoints may generate
4306 different signals (SIGILL or SIGEMT for instance), but it is less
4307 clear where the PC is pointing afterwards. It may not match
4308 gdbarch_decr_pc_after_break. I don't know any specific target that
4309 generates these signals at breakpoints (the code has been in GDB since at
4310 least 1992) so I can not guess how to handle them here.
4312 In earlier versions of GDB, a target with
4313 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
4314 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
4315 target with both of these set in GDB history, and it seems unlikely to be
4316 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
4318 if (ws
->kind
!= TARGET_WAITKIND_STOPPED
)
4321 if (ws
->value
.sig
!= GDB_SIGNAL_TRAP
)
4324 /* In reverse execution, when a breakpoint is hit, the instruction
4325 under it has already been de-executed. The reported PC always
4326 points at the breakpoint address, so adjusting it further would
4327 be wrong. E.g., consider this case on a decr_pc_after_break == 1
4330 B1 0x08000000 : INSN1
4331 B2 0x08000001 : INSN2
4333 PC -> 0x08000003 : INSN4
4335 Say you're stopped at 0x08000003 as above. Reverse continuing
4336 from that point should hit B2 as below. Reading the PC when the
4337 SIGTRAP is reported should read 0x08000001 and INSN2 should have
4338 been de-executed already.
4340 B1 0x08000000 : INSN1
4341 B2 PC -> 0x08000001 : INSN2
4345 We can't apply the same logic as for forward execution, because
4346 we would wrongly adjust the PC to 0x08000000, since there's a
4347 breakpoint at PC - 1. We'd then report a hit on B1, although
4348 INSN1 hadn't been de-executed yet. Doing nothing is the correct
4350 if (execution_direction
== EXEC_REVERSE
)
4353 /* If the target can tell whether the thread hit a SW breakpoint,
4354 trust it. Targets that can tell also adjust the PC
4356 if (target_supports_stopped_by_sw_breakpoint ())
4359 /* Note that relying on whether a breakpoint is planted in memory to
4360 determine this can fail. E.g,. the breakpoint could have been
4361 removed since. Or the thread could have been told to step an
4362 instruction the size of a breakpoint instruction, and only
4363 _after_ was a breakpoint inserted at its address. */
4365 /* If this target does not decrement the PC after breakpoints, then
4366 we have nothing to do. */
4367 regcache
= get_thread_regcache (thread
);
4368 gdbarch
= regcache
->arch ();
4370 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
4374 const address_space
*aspace
= regcache
->aspace ();
4376 /* Find the location where (if we've hit a breakpoint) the
4377 breakpoint would be. */
4378 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
4380 /* If the target can't tell whether a software breakpoint triggered,
4381 fallback to figuring it out based on breakpoints we think were
4382 inserted in the target, and on whether the thread was stepped or
4385 /* Check whether there actually is a software breakpoint inserted at
4388 If in non-stop mode, a race condition is possible where we've
4389 removed a breakpoint, but stop events for that breakpoint were
4390 already queued and arrive later. To suppress those spurious
4391 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
4392 and retire them after a number of stop events are reported. Note
4393 this is an heuristic and can thus get confused. The real fix is
4394 to get the "stopped by SW BP and needs adjustment" info out of
4395 the target/kernel (and thus never reach here; see above). */
4396 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
4397 || (target_is_non_stop_p ()
4398 && moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
4400 gdb::optional
<scoped_restore_tmpl
<int>> restore_operation_disable
;
4402 if (record_full_is_used ())
4403 restore_operation_disable
.emplace
4404 (record_full_gdb_operation_disable_set ());
4406 /* When using hardware single-step, a SIGTRAP is reported for both
4407 a completed single-step and a software breakpoint. Need to
4408 differentiate between the two, as the latter needs adjusting
4409 but the former does not.
4411 The SIGTRAP can be due to a completed hardware single-step only if
4412 - we didn't insert software single-step breakpoints
4413 - this thread is currently being stepped
4415 If any of these events did not occur, we must have stopped due
4416 to hitting a software breakpoint, and have to back up to the
4419 As a special case, we could have hardware single-stepped a
4420 software breakpoint. In this case (prev_pc == breakpoint_pc),
4421 we also need to back up to the breakpoint address. */
4423 if (thread_has_single_step_breakpoints_set (thread
)
4424 || !currently_stepping (thread
)
4425 || (thread
->stepped_breakpoint
4426 && thread
->prev_pc
== breakpoint_pc
))
4427 regcache_write_pc (regcache
, breakpoint_pc
);
4432 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
4434 for (frame
= get_prev_frame (frame
);
4436 frame
= get_prev_frame (frame
))
4438 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
4441 if (get_frame_type (frame
) != INLINE_FRAME
)
4448 /* Look for an inline frame that is marked for skip.
4449 If PREV_FRAME is TRUE start at the previous frame,
4450 otherwise start at the current frame. Stop at the
4451 first non-inline frame, or at the frame where the
4455 inline_frame_is_marked_for_skip (bool prev_frame
, struct thread_info
*tp
)
4457 struct frame_info
*frame
= get_current_frame ();
4460 frame
= get_prev_frame (frame
);
4462 for (; frame
!= NULL
; frame
= get_prev_frame (frame
))
4464 const char *fn
= NULL
;
4465 symtab_and_line sal
;
4468 if (frame_id_eq (get_frame_id (frame
), tp
->control
.step_frame_id
))
4470 if (get_frame_type (frame
) != INLINE_FRAME
)
4473 sal
= find_frame_sal (frame
);
4474 sym
= get_frame_function (frame
);
4477 fn
= sym
->print_name ();
4480 && function_name_is_marked_for_skip (fn
, sal
))
4487 /* If the event thread has the stop requested flag set, pretend it
4488 stopped for a GDB_SIGNAL_0 (i.e., as if it stopped due to
4492 handle_stop_requested (struct execution_control_state
*ecs
)
4494 if (ecs
->event_thread
->stop_requested
)
4496 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
4497 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
4498 handle_signal_stop (ecs
);
4504 /* Auxiliary function that handles syscall entry/return events.
4505 It returns true if the inferior should keep going (and GDB
4506 should ignore the event), or false if the event deserves to be
4510 handle_syscall_event (struct execution_control_state
*ecs
)
4512 struct regcache
*regcache
;
4515 context_switch (ecs
);
4517 regcache
= get_thread_regcache (ecs
->event_thread
);
4518 syscall_number
= ecs
->ws
.value
.syscall_number
;
4519 ecs
->event_thread
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4521 if (catch_syscall_enabled () > 0
4522 && catching_syscall_number (syscall_number
) > 0)
4524 infrun_debug_printf ("syscall number=%d", syscall_number
);
4526 ecs
->event_thread
->control
.stop_bpstat
4527 = bpstat_stop_status (regcache
->aspace (),
4528 ecs
->event_thread
->suspend
.stop_pc
,
4529 ecs
->event_thread
, &ecs
->ws
);
4531 if (handle_stop_requested (ecs
))
4534 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4536 /* Catchpoint hit. */
4541 if (handle_stop_requested (ecs
))
4544 /* If no catchpoint triggered for this, then keep going. */
4550 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4553 fill_in_stop_func (struct gdbarch
*gdbarch
,
4554 struct execution_control_state
*ecs
)
4556 if (!ecs
->stop_func_filled_in
)
4559 const general_symbol_info
*gsi
;
4561 /* Don't care about return value; stop_func_start and stop_func_name
4562 will both be 0 if it doesn't work. */
4563 find_pc_partial_function_sym (ecs
->event_thread
->suspend
.stop_pc
,
4565 &ecs
->stop_func_start
,
4566 &ecs
->stop_func_end
,
4568 ecs
->stop_func_name
= gsi
== nullptr ? nullptr : gsi
->print_name ();
4570 /* The call to find_pc_partial_function, above, will set
4571 stop_func_start and stop_func_end to the start and end
4572 of the range containing the stop pc. If this range
4573 contains the entry pc for the block (which is always the
4574 case for contiguous blocks), advance stop_func_start past
4575 the function's start offset and entrypoint. Note that
4576 stop_func_start is NOT advanced when in a range of a
4577 non-contiguous block that does not contain the entry pc. */
4578 if (block
!= nullptr
4579 && ecs
->stop_func_start
<= BLOCK_ENTRY_PC (block
)
4580 && BLOCK_ENTRY_PC (block
) < ecs
->stop_func_end
)
4582 ecs
->stop_func_start
4583 += gdbarch_deprecated_function_start_offset (gdbarch
);
4585 if (gdbarch_skip_entrypoint_p (gdbarch
))
4586 ecs
->stop_func_start
4587 = gdbarch_skip_entrypoint (gdbarch
, ecs
->stop_func_start
);
4590 ecs
->stop_func_filled_in
= 1;
4595 /* Return the STOP_SOON field of the inferior pointed at by ECS. */
4597 static enum stop_kind
4598 get_inferior_stop_soon (execution_control_state
*ecs
)
4600 struct inferior
*inf
= find_inferior_ptid (ecs
->target
, ecs
->ptid
);
4602 gdb_assert (inf
!= NULL
);
4603 return inf
->control
.stop_soon
;
4606 /* Poll for one event out of the current target. Store the resulting
4607 waitstatus in WS, and return the event ptid. Does not block. */
4610 poll_one_curr_target (struct target_waitstatus
*ws
)
4614 overlay_cache_invalid
= 1;
4616 /* Flush target cache before starting to handle each event.
4617 Target was running and cache could be stale. This is just a
4618 heuristic. Running threads may modify target memory, but we
4619 don't get any event. */
4620 target_dcache_invalidate ();
4622 if (deprecated_target_wait_hook
)
4623 event_ptid
= deprecated_target_wait_hook (minus_one_ptid
, ws
, TARGET_WNOHANG
);
4625 event_ptid
= target_wait (minus_one_ptid
, ws
, TARGET_WNOHANG
);
4628 print_target_wait_results (minus_one_ptid
, event_ptid
, ws
);
4633 /* Wait for one event out of any target. */
4635 static wait_one_event
4640 for (inferior
*inf
: all_inferiors ())
4642 process_stratum_target
*target
= inf
->process_target ();
4644 || !target
->is_async_p ()
4645 || !target
->threads_executing
)
4648 switch_to_inferior_no_thread (inf
);
4650 wait_one_event event
;
4651 event
.target
= target
;
4652 event
.ptid
= poll_one_curr_target (&event
.ws
);
4654 if (event
.ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4656 /* If nothing is resumed, remove the target from the
4660 else if (event
.ws
.kind
!= TARGET_WAITKIND_IGNORE
)
4664 /* Block waiting for some event. */
4671 for (inferior
*inf
: all_inferiors ())
4673 process_stratum_target
*target
= inf
->process_target ();
4675 || !target
->is_async_p ()
4676 || !target
->threads_executing
)
4679 int fd
= target
->async_wait_fd ();
4680 FD_SET (fd
, &readfds
);
4687 /* No waitable targets left. All must be stopped. */
4688 return {NULL
, minus_one_ptid
, {TARGET_WAITKIND_NO_RESUMED
}};
4693 int numfds
= interruptible_select (nfds
, &readfds
, 0, NULL
, 0);
4699 perror_with_name ("interruptible_select");
4704 /* Save the thread's event and stop reason to process it later. */
4707 save_waitstatus (struct thread_info
*tp
, const target_waitstatus
*ws
)
4709 infrun_debug_printf ("saving status %s for %d.%ld.%ld",
4710 target_waitstatus_to_string (ws
).c_str (),
4715 /* Record for later. */
4716 tp
->suspend
.waitstatus
= *ws
;
4717 tp
->suspend
.waitstatus_pending_p
= 1;
4719 if (ws
->kind
== TARGET_WAITKIND_STOPPED
4720 && ws
->value
.sig
== GDB_SIGNAL_TRAP
)
4722 struct regcache
*regcache
= get_thread_regcache (tp
);
4723 const address_space
*aspace
= regcache
->aspace ();
4724 CORE_ADDR pc
= regcache_read_pc (regcache
);
4726 adjust_pc_after_break (tp
, &tp
->suspend
.waitstatus
);
4728 scoped_restore_current_thread restore_thread
;
4729 switch_to_thread (tp
);
4731 if (target_stopped_by_watchpoint ())
4733 tp
->suspend
.stop_reason
4734 = TARGET_STOPPED_BY_WATCHPOINT
;
4736 else if (target_supports_stopped_by_sw_breakpoint ()
4737 && target_stopped_by_sw_breakpoint ())
4739 tp
->suspend
.stop_reason
4740 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4742 else if (target_supports_stopped_by_hw_breakpoint ()
4743 && target_stopped_by_hw_breakpoint ())
4745 tp
->suspend
.stop_reason
4746 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4748 else if (!target_supports_stopped_by_hw_breakpoint ()
4749 && hardware_breakpoint_inserted_here_p (aspace
,
4752 tp
->suspend
.stop_reason
4753 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4755 else if (!target_supports_stopped_by_sw_breakpoint ()
4756 && software_breakpoint_inserted_here_p (aspace
,
4759 tp
->suspend
.stop_reason
4760 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4762 else if (!thread_has_single_step_breakpoints_set (tp
)
4763 && currently_stepping (tp
))
4765 tp
->suspend
.stop_reason
4766 = TARGET_STOPPED_BY_SINGLE_STEP
;
4771 /* Mark the non-executing threads accordingly. In all-stop, all
4772 threads of all processes are stopped when we get any event
4773 reported. In non-stop mode, only the event thread stops. */
4776 mark_non_executing_threads (process_stratum_target
*target
,
4778 struct target_waitstatus ws
)
4782 if (!target_is_non_stop_p ())
4783 mark_ptid
= minus_one_ptid
;
4784 else if (ws
.kind
== TARGET_WAITKIND_SIGNALLED
4785 || ws
.kind
== TARGET_WAITKIND_EXITED
)
4787 /* If we're handling a process exit in non-stop mode, even
4788 though threads haven't been deleted yet, one would think
4789 that there is nothing to do, as threads of the dead process
4790 will be soon deleted, and threads of any other process were
4791 left running. However, on some targets, threads survive a
4792 process exit event. E.g., for the "checkpoint" command,
4793 when the current checkpoint/fork exits, linux-fork.c
4794 automatically switches to another fork from within
4795 target_mourn_inferior, by associating the same
4796 inferior/thread to another fork. We haven't mourned yet at
4797 this point, but we must mark any threads left in the
4798 process as not-executing so that finish_thread_state marks
4799 them stopped (in the user's perspective) if/when we present
4800 the stop to the user. */
4801 mark_ptid
= ptid_t (event_ptid
.pid ());
4804 mark_ptid
= event_ptid
;
4806 set_executing (target
, mark_ptid
, false);
4808 /* Likewise the resumed flag. */
4809 set_resumed (target
, mark_ptid
, false);
4812 /* Handle one event after stopping threads. If the eventing thread
4813 reports back any interesting event, we leave it pending. If the
4814 eventing thread was in the middle of a displaced step, we
4815 cancel/finish it, and unless the thread's inferior is being
4816 detached, put the thread back in the step-over chain. Returns true
4817 if there are no resumed threads left in the target (thus there's no
4818 point in waiting further), false otherwise. */
4821 handle_one (const wait_one_event
&event
)
4824 ("%s %s", target_waitstatus_to_string (&event
.ws
).c_str (),
4825 target_pid_to_str (event
.ptid
).c_str ());
4827 if (event
.ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4829 /* All resumed threads exited. */
4832 else if (event
.ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
4833 || event
.ws
.kind
== TARGET_WAITKIND_EXITED
4834 || event
.ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
4836 /* One thread/process exited/signalled. */
4838 thread_info
*t
= nullptr;
4840 /* The target may have reported just a pid. If so, try
4841 the first non-exited thread. */
4842 if (event
.ptid
.is_pid ())
4844 int pid
= event
.ptid
.pid ();
4845 inferior
*inf
= find_inferior_pid (event
.target
, pid
);
4846 for (thread_info
*tp
: inf
->non_exited_threads ())
4852 /* If there is no available thread, the event would
4853 have to be appended to a per-inferior event list,
4854 which does not exist (and if it did, we'd have
4855 to adjust run control command to be able to
4856 resume such an inferior). We assert here instead
4857 of going into an infinite loop. */
4858 gdb_assert (t
!= nullptr);
4861 ("using %s", target_pid_to_str (t
->ptid
).c_str ());
4865 t
= find_thread_ptid (event
.target
, event
.ptid
);
4866 /* Check if this is the first time we see this thread.
4867 Don't bother adding if it individually exited. */
4869 && event
.ws
.kind
!= TARGET_WAITKIND_THREAD_EXITED
)
4870 t
= add_thread (event
.target
, event
.ptid
);
4875 /* Set the threads as non-executing to avoid
4876 another stop attempt on them. */
4877 switch_to_thread_no_regs (t
);
4878 mark_non_executing_threads (event
.target
, event
.ptid
,
4880 save_waitstatus (t
, &event
.ws
);
4881 t
->stop_requested
= false;
4886 thread_info
*t
= find_thread_ptid (event
.target
, event
.ptid
);
4888 t
= add_thread (event
.target
, event
.ptid
);
4890 t
->stop_requested
= 0;
4893 t
->control
.may_range_step
= 0;
4895 /* This may be the first time we see the inferior report
4897 inferior
*inf
= find_inferior_ptid (event
.target
, event
.ptid
);
4898 if (inf
->needs_setup
)
4900 switch_to_thread_no_regs (t
);
4904 if (event
.ws
.kind
== TARGET_WAITKIND_STOPPED
4905 && event
.ws
.value
.sig
== GDB_SIGNAL_0
)
4907 /* We caught the event that we intended to catch, so
4908 there's no event pending. */
4909 t
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
4910 t
->suspend
.waitstatus_pending_p
= 0;
4912 if (displaced_step_finish (t
, GDB_SIGNAL_0
)
4913 == DISPLACED_STEP_FINISH_STATUS_NOT_EXECUTED
)
4915 /* Add it back to the step-over queue. */
4917 ("displaced-step of %s canceled",
4918 target_pid_to_str (t
->ptid
).c_str ());
4920 t
->control
.trap_expected
= 0;
4921 if (!t
->inf
->detaching
)
4922 global_thread_step_over_chain_enqueue (t
);
4927 enum gdb_signal sig
;
4928 struct regcache
*regcache
;
4931 ("target_wait %s, saving status for %d.%ld.%ld",
4932 target_waitstatus_to_string (&event
.ws
).c_str (),
4933 t
->ptid
.pid (), t
->ptid
.lwp (), t
->ptid
.tid ());
4935 /* Record for later. */
4936 save_waitstatus (t
, &event
.ws
);
4938 sig
= (event
.ws
.kind
== TARGET_WAITKIND_STOPPED
4939 ? event
.ws
.value
.sig
: GDB_SIGNAL_0
);
4941 if (displaced_step_finish (t
, sig
)
4942 == DISPLACED_STEP_FINISH_STATUS_NOT_EXECUTED
)
4944 /* Add it back to the step-over queue. */
4945 t
->control
.trap_expected
= 0;
4946 if (!t
->inf
->detaching
)
4947 global_thread_step_over_chain_enqueue (t
);
4950 regcache
= get_thread_regcache (t
);
4951 t
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4953 infrun_debug_printf ("saved stop_pc=%s for %s "
4954 "(currently_stepping=%d)",
4955 paddress (target_gdbarch (),
4956 t
->suspend
.stop_pc
),
4957 target_pid_to_str (t
->ptid
).c_str (),
4958 currently_stepping (t
));
4968 stop_all_threads (const char *reason
, inferior
*inf
)
4970 /* We may need multiple passes to discover all threads. */
4974 gdb_assert (exists_non_stop_target ());
4976 INFRUN_SCOPED_DEBUG_START_END ("reason=%s, inf=%d", reason
,
4977 inf
!= nullptr ? inf
->num
: -1);
4979 scoped_restore_current_thread restore_thread
;
4981 /* Enable thread events on relevant targets. */
4982 for (auto *target
: all_non_exited_process_targets ())
4984 if (inf
!= nullptr && inf
->process_target () != target
)
4987 switch_to_target_no_thread (target
);
4988 target_thread_events (true);
4993 /* Disable thread events on relevant targets. */
4994 for (auto *target
: all_non_exited_process_targets ())
4996 if (inf
!= nullptr && inf
->process_target () != target
)
4999 switch_to_target_no_thread (target
);
5000 target_thread_events (false);
5003 /* Use debug_prefixed_printf directly to get a meaningful function
5006 debug_prefixed_printf ("infrun", "stop_all_threads", "done");
5009 /* Request threads to stop, and then wait for the stops. Because
5010 threads we already know about can spawn more threads while we're
5011 trying to stop them, and we only learn about new threads when we
5012 update the thread list, do this in a loop, and keep iterating
5013 until two passes find no threads that need to be stopped. */
5014 for (pass
= 0; pass
< 2; pass
++, iterations
++)
5016 infrun_debug_printf ("pass=%d, iterations=%d", pass
, iterations
);
5019 int waits_needed
= 0;
5021 for (auto *target
: all_non_exited_process_targets ())
5023 if (inf
!= nullptr && inf
->process_target () != target
)
5026 switch_to_target_no_thread (target
);
5027 update_thread_list ();
5030 /* Go through all threads looking for threads that we need
5031 to tell the target to stop. */
5032 for (thread_info
*t
: all_non_exited_threads ())
5034 if (inf
!= nullptr && t
->inf
!= inf
)
5037 /* For a single-target setting with an all-stop target,
5038 we would not even arrive here. For a multi-target
5039 setting, until GDB is able to handle a mixture of
5040 all-stop and non-stop targets, simply skip all-stop
5041 targets' threads. This should be fine due to the
5042 protection of 'check_multi_target_resumption'. */
5044 switch_to_thread_no_regs (t
);
5045 if (!target_is_non_stop_p ())
5050 /* If already stopping, don't request a stop again.
5051 We just haven't seen the notification yet. */
5052 if (!t
->stop_requested
)
5054 infrun_debug_printf (" %s executing, need stop",
5055 target_pid_to_str (t
->ptid
).c_str ());
5056 target_stop (t
->ptid
);
5057 t
->stop_requested
= 1;
5061 infrun_debug_printf (" %s executing, already stopping",
5062 target_pid_to_str (t
->ptid
).c_str ());
5065 if (t
->stop_requested
)
5070 infrun_debug_printf (" %s not executing",
5071 target_pid_to_str (t
->ptid
).c_str ());
5073 /* The thread may be not executing, but still be
5074 resumed with a pending status to process. */
5079 if (waits_needed
== 0)
5082 /* If we find new threads on the second iteration, restart
5083 over. We want to see two iterations in a row with all
5088 for (int i
= 0; i
< waits_needed
; i
++)
5090 wait_one_event event
= wait_one ();
5091 if (handle_one (event
))
5098 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
5101 handle_no_resumed (struct execution_control_state
*ecs
)
5103 if (target_can_async_p ())
5105 bool any_sync
= false;
5107 for (ui
*ui
: all_uis ())
5109 if (ui
->prompt_state
== PROMPT_BLOCKED
)
5117 /* There were no unwaited-for children left in the target, but,
5118 we're not synchronously waiting for events either. Just
5121 infrun_debug_printf ("TARGET_WAITKIND_NO_RESUMED (ignoring: bg)");
5122 prepare_to_wait (ecs
);
5127 /* Otherwise, if we were running a synchronous execution command, we
5128 may need to cancel it and give the user back the terminal.
5130 In non-stop mode, the target can't tell whether we've already
5131 consumed previous stop events, so it can end up sending us a
5132 no-resumed event like so:
5134 #0 - thread 1 is left stopped
5136 #1 - thread 2 is resumed and hits breakpoint
5137 -> TARGET_WAITKIND_STOPPED
5139 #2 - thread 3 is resumed and exits
5140 this is the last resumed thread, so
5141 -> TARGET_WAITKIND_NO_RESUMED
5143 #3 - gdb processes stop for thread 2 and decides to re-resume
5146 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
5147 thread 2 is now resumed, so the event should be ignored.
5149 IOW, if the stop for thread 2 doesn't end a foreground command,
5150 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
5151 event. But it could be that the event meant that thread 2 itself
5152 (or whatever other thread was the last resumed thread) exited.
5154 To address this we refresh the thread list and check whether we
5155 have resumed threads _now_. In the example above, this removes
5156 thread 3 from the thread list. If thread 2 was re-resumed, we
5157 ignore this event. If we find no thread resumed, then we cancel
5158 the synchronous command and show "no unwaited-for " to the
5161 inferior
*curr_inf
= current_inferior ();
5163 scoped_restore_current_thread restore_thread
;
5165 for (auto *target
: all_non_exited_process_targets ())
5167 switch_to_target_no_thread (target
);
5168 update_thread_list ();
5173 - the current target has no thread executing, and
5174 - the current inferior is native, and
5175 - the current inferior is the one which has the terminal, and
5178 then a Ctrl-C from this point on would remain stuck in the
5179 kernel, until a thread resumes and dequeues it. That would
5180 result in the GDB CLI not reacting to Ctrl-C, not able to
5181 interrupt the program. To address this, if the current inferior
5182 no longer has any thread executing, we give the terminal to some
5183 other inferior that has at least one thread executing. */
5184 bool swap_terminal
= true;
5186 /* Whether to ignore this TARGET_WAITKIND_NO_RESUMED event, or
5187 whether to report it to the user. */
5188 bool ignore_event
= false;
5190 for (thread_info
*thread
: all_non_exited_threads ())
5192 if (swap_terminal
&& thread
->executing
)
5194 if (thread
->inf
!= curr_inf
)
5196 target_terminal::ours ();
5198 switch_to_thread (thread
);
5199 target_terminal::inferior ();
5201 swap_terminal
= false;
5205 && (thread
->executing
5206 || thread
->suspend
.waitstatus_pending_p
))
5208 /* Either there were no unwaited-for children left in the
5209 target at some point, but there are now, or some target
5210 other than the eventing one has unwaited-for children
5211 left. Just ignore. */
5212 infrun_debug_printf ("TARGET_WAITKIND_NO_RESUMED "
5213 "(ignoring: found resumed)");
5215 ignore_event
= true;
5218 if (ignore_event
&& !swap_terminal
)
5224 switch_to_inferior_no_thread (curr_inf
);
5225 prepare_to_wait (ecs
);
5229 /* Go ahead and report the event. */
5233 /* Given an execution control state that has been freshly filled in by
5234 an event from the inferior, figure out what it means and take
5237 The alternatives are:
5239 1) stop_waiting and return; to really stop and return to the
5242 2) keep_going and return; to wait for the next event (set
5243 ecs->event_thread->stepping_over_breakpoint to 1 to single step
5247 handle_inferior_event (struct execution_control_state
*ecs
)
5249 /* Make sure that all temporary struct value objects that were
5250 created during the handling of the event get deleted at the
5252 scoped_value_mark free_values
;
5254 infrun_debug_printf ("%s", target_waitstatus_to_string (&ecs
->ws
).c_str ());
5256 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
5258 /* We had an event in the inferior, but we are not interested in
5259 handling it at this level. The lower layers have already
5260 done what needs to be done, if anything.
5262 One of the possible circumstances for this is when the
5263 inferior produces output for the console. The inferior has
5264 not stopped, and we are ignoring the event. Another possible
5265 circumstance is any event which the lower level knows will be
5266 reported multiple times without an intervening resume. */
5267 prepare_to_wait (ecs
);
5271 if (ecs
->ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
)
5273 prepare_to_wait (ecs
);
5277 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
5278 && handle_no_resumed (ecs
))
5281 /* Cache the last target/ptid/waitstatus. */
5282 set_last_target_status (ecs
->target
, ecs
->ptid
, ecs
->ws
);
5284 /* Always clear state belonging to the previous time we stopped. */
5285 stop_stack_dummy
= STOP_NONE
;
5287 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
5289 /* No unwaited-for children left. IOW, all resumed children
5291 stop_print_frame
= false;
5296 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
5297 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
5299 ecs
->event_thread
= find_thread_ptid (ecs
->target
, ecs
->ptid
);
5300 /* If it's a new thread, add it to the thread database. */
5301 if (ecs
->event_thread
== NULL
)
5302 ecs
->event_thread
= add_thread (ecs
->target
, ecs
->ptid
);
5304 /* Disable range stepping. If the next step request could use a
5305 range, this will be end up re-enabled then. */
5306 ecs
->event_thread
->control
.may_range_step
= 0;
5309 /* Dependent on valid ECS->EVENT_THREAD. */
5310 adjust_pc_after_break (ecs
->event_thread
, &ecs
->ws
);
5312 /* Dependent on the current PC value modified by adjust_pc_after_break. */
5313 reinit_frame_cache ();
5315 breakpoint_retire_moribund ();
5317 /* First, distinguish signals caused by the debugger from signals
5318 that have to do with the program's own actions. Note that
5319 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
5320 on the operating system version. Here we detect when a SIGILL or
5321 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
5322 something similar for SIGSEGV, since a SIGSEGV will be generated
5323 when we're trying to execute a breakpoint instruction on a
5324 non-executable stack. This happens for call dummy breakpoints
5325 for architectures like SPARC that place call dummies on the
5327 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
5328 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
5329 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
5330 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
5332 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
5334 if (breakpoint_inserted_here_p (regcache
->aspace (),
5335 regcache_read_pc (regcache
)))
5337 infrun_debug_printf ("Treating signal as SIGTRAP");
5338 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
5342 mark_non_executing_threads (ecs
->target
, ecs
->ptid
, ecs
->ws
);
5344 switch (ecs
->ws
.kind
)
5346 case TARGET_WAITKIND_LOADED
:
5348 context_switch (ecs
);
5349 /* Ignore gracefully during startup of the inferior, as it might
5350 be the shell which has just loaded some objects, otherwise
5351 add the symbols for the newly loaded objects. Also ignore at
5352 the beginning of an attach or remote session; we will query
5353 the full list of libraries once the connection is
5356 stop_kind stop_soon
= get_inferior_stop_soon (ecs
);
5357 if (stop_soon
== NO_STOP_QUIETLY
)
5359 struct regcache
*regcache
;
5361 regcache
= get_thread_regcache (ecs
->event_thread
);
5363 handle_solib_event ();
5365 ecs
->event_thread
->control
.stop_bpstat
5366 = bpstat_stop_status (regcache
->aspace (),
5367 ecs
->event_thread
->suspend
.stop_pc
,
5368 ecs
->event_thread
, &ecs
->ws
);
5370 if (handle_stop_requested (ecs
))
5373 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5375 /* A catchpoint triggered. */
5376 process_event_stop_test (ecs
);
5380 /* If requested, stop when the dynamic linker notifies
5381 gdb of events. This allows the user to get control
5382 and place breakpoints in initializer routines for
5383 dynamically loaded objects (among other things). */
5384 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5385 if (stop_on_solib_events
)
5387 /* Make sure we print "Stopped due to solib-event" in
5389 stop_print_frame
= true;
5396 /* If we are skipping through a shell, or through shared library
5397 loading that we aren't interested in, resume the program. If
5398 we're running the program normally, also resume. */
5399 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
5401 /* Loading of shared libraries might have changed breakpoint
5402 addresses. Make sure new breakpoints are inserted. */
5403 if (stop_soon
== NO_STOP_QUIETLY
)
5404 insert_breakpoints ();
5405 resume (GDB_SIGNAL_0
);
5406 prepare_to_wait (ecs
);
5410 /* But stop if we're attaching or setting up a remote
5412 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5413 || stop_soon
== STOP_QUIETLY_REMOTE
)
5415 infrun_debug_printf ("quietly stopped");
5420 internal_error (__FILE__
, __LINE__
,
5421 _("unhandled stop_soon: %d"), (int) stop_soon
);
5424 case TARGET_WAITKIND_SPURIOUS
:
5425 if (handle_stop_requested (ecs
))
5427 context_switch (ecs
);
5428 resume (GDB_SIGNAL_0
);
5429 prepare_to_wait (ecs
);
5432 case TARGET_WAITKIND_THREAD_CREATED
:
5433 if (handle_stop_requested (ecs
))
5435 context_switch (ecs
);
5436 if (!switch_back_to_stepped_thread (ecs
))
5440 case TARGET_WAITKIND_EXITED
:
5441 case TARGET_WAITKIND_SIGNALLED
:
5443 /* Depending on the system, ecs->ptid may point to a thread or
5444 to a process. On some targets, target_mourn_inferior may
5445 need to have access to the just-exited thread. That is the
5446 case of GNU/Linux's "checkpoint" support, for example.
5447 Call the switch_to_xxx routine as appropriate. */
5448 thread_info
*thr
= find_thread_ptid (ecs
->target
, ecs
->ptid
);
5450 switch_to_thread (thr
);
5453 inferior
*inf
= find_inferior_ptid (ecs
->target
, ecs
->ptid
);
5454 switch_to_inferior_no_thread (inf
);
5457 handle_vfork_child_exec_or_exit (0);
5458 target_terminal::ours (); /* Must do this before mourn anyway. */
5460 /* Clearing any previous state of convenience variables. */
5461 clear_exit_convenience_vars ();
5463 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5465 /* Record the exit code in the convenience variable $_exitcode, so
5466 that the user can inspect this again later. */
5467 set_internalvar_integer (lookup_internalvar ("_exitcode"),
5468 (LONGEST
) ecs
->ws
.value
.integer
);
5470 /* Also record this in the inferior itself. */
5471 current_inferior ()->has_exit_code
= 1;
5472 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
5474 /* Support the --return-child-result option. */
5475 return_child_result_value
= ecs
->ws
.value
.integer
;
5477 gdb::observers::exited
.notify (ecs
->ws
.value
.integer
);
5481 struct gdbarch
*gdbarch
= current_inferior ()->gdbarch
;
5483 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
5485 /* Set the value of the internal variable $_exitsignal,
5486 which holds the signal uncaught by the inferior. */
5487 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
5488 gdbarch_gdb_signal_to_target (gdbarch
,
5489 ecs
->ws
.value
.sig
));
5493 /* We don't have access to the target's method used for
5494 converting between signal numbers (GDB's internal
5495 representation <-> target's representation).
5496 Therefore, we cannot do a good job at displaying this
5497 information to the user. It's better to just warn
5498 her about it (if infrun debugging is enabled), and
5500 infrun_debug_printf ("Cannot fill $_exitsignal with the correct "
5504 gdb::observers::signal_exited
.notify (ecs
->ws
.value
.sig
);
5507 gdb_flush (gdb_stdout
);
5508 target_mourn_inferior (inferior_ptid
);
5509 stop_print_frame
= false;
5513 case TARGET_WAITKIND_FORKED
:
5514 case TARGET_WAITKIND_VFORKED
:
5515 /* Check whether the inferior is displaced stepping. */
5517 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
5518 struct gdbarch
*gdbarch
= regcache
->arch ();
5519 inferior
*parent_inf
= find_inferior_ptid (ecs
->target
, ecs
->ptid
);
5521 /* If this is a fork (child gets its own address space copy)
5522 and some displaced step buffers were in use at the time of
5523 the fork, restore the displaced step buffer bytes in the
5526 Architectures which support displaced stepping and fork
5527 events must supply an implementation of
5528 gdbarch_displaced_step_restore_all_in_ptid. This is not
5529 enforced during gdbarch validation to support architectures
5530 which support displaced stepping but not forks. */
5531 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
5532 && gdbarch_supports_displaced_stepping (gdbarch
))
5533 gdbarch_displaced_step_restore_all_in_ptid
5534 (gdbarch
, parent_inf
, ecs
->ws
.value
.related_pid
);
5536 /* If displaced stepping is supported, and thread ecs->ptid is
5537 displaced stepping. */
5538 if (displaced_step_in_progress_thread (ecs
->event_thread
))
5540 struct regcache
*child_regcache
;
5541 CORE_ADDR parent_pc
;
5543 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
5544 indicating that the displaced stepping of syscall instruction
5545 has been done. Perform cleanup for parent process here. Note
5546 that this operation also cleans up the child process for vfork,
5547 because their pages are shared. */
5548 displaced_step_finish (ecs
->event_thread
, GDB_SIGNAL_TRAP
);
5549 /* Start a new step-over in another thread if there's one
5553 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
5554 the child's PC is also within the scratchpad. Set the child's PC
5555 to the parent's PC value, which has already been fixed up.
5556 FIXME: we use the parent's aspace here, although we're touching
5557 the child, because the child hasn't been added to the inferior
5558 list yet at this point. */
5561 = get_thread_arch_aspace_regcache (parent_inf
->process_target (),
5562 ecs
->ws
.value
.related_pid
,
5564 parent_inf
->aspace
);
5565 /* Read PC value of parent process. */
5566 parent_pc
= regcache_read_pc (regcache
);
5568 displaced_debug_printf ("write child pc from %s to %s",
5570 regcache_read_pc (child_regcache
)),
5571 paddress (gdbarch
, parent_pc
));
5573 regcache_write_pc (child_regcache
, parent_pc
);
5577 context_switch (ecs
);
5579 /* Immediately detach breakpoints from the child before there's
5580 any chance of letting the user delete breakpoints from the
5581 breakpoint lists. If we don't do this early, it's easy to
5582 leave left over traps in the child, vis: "break foo; catch
5583 fork; c; <fork>; del; c; <child calls foo>". We only follow
5584 the fork on the last `continue', and by that time the
5585 breakpoint at "foo" is long gone from the breakpoint table.
5586 If we vforked, then we don't need to unpatch here, since both
5587 parent and child are sharing the same memory pages; we'll
5588 need to unpatch at follow/detach time instead to be certain
5589 that new breakpoints added between catchpoint hit time and
5590 vfork follow are detached. */
5591 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
5593 /* This won't actually modify the breakpoint list, but will
5594 physically remove the breakpoints from the child. */
5595 detach_breakpoints (ecs
->ws
.value
.related_pid
);
5598 delete_just_stopped_threads_single_step_breakpoints ();
5600 /* In case the event is caught by a catchpoint, remember that
5601 the event is to be followed at the next resume of the thread,
5602 and not immediately. */
5603 ecs
->event_thread
->pending_follow
= ecs
->ws
;
5605 ecs
->event_thread
->suspend
.stop_pc
5606 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
5608 ecs
->event_thread
->control
.stop_bpstat
5609 = bpstat_stop_status (get_current_regcache ()->aspace (),
5610 ecs
->event_thread
->suspend
.stop_pc
,
5611 ecs
->event_thread
, &ecs
->ws
);
5613 if (handle_stop_requested (ecs
))
5616 /* If no catchpoint triggered for this, then keep going. Note
5617 that we're interested in knowing the bpstat actually causes a
5618 stop, not just if it may explain the signal. Software
5619 watchpoints, for example, always appear in the bpstat. */
5620 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5623 = (follow_fork_mode_string
== follow_fork_mode_child
);
5625 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5627 process_stratum_target
*targ
5628 = ecs
->event_thread
->inf
->process_target ();
5630 bool should_resume
= follow_fork ();
5632 /* Note that one of these may be an invalid pointer,
5633 depending on detach_fork. */
5634 thread_info
*parent
= ecs
->event_thread
;
5636 = find_thread_ptid (targ
, ecs
->ws
.value
.related_pid
);
5638 /* At this point, the parent is marked running, and the
5639 child is marked stopped. */
5641 /* If not resuming the parent, mark it stopped. */
5642 if (follow_child
&& !detach_fork
&& !non_stop
&& !sched_multi
)
5643 parent
->set_running (false);
5645 /* If resuming the child, mark it running. */
5646 if (follow_child
|| (!detach_fork
&& (non_stop
|| sched_multi
)))
5647 child
->set_running (true);
5649 /* In non-stop mode, also resume the other branch. */
5650 if (!detach_fork
&& (non_stop
5651 || (sched_multi
&& target_is_non_stop_p ())))
5654 switch_to_thread (parent
);
5656 switch_to_thread (child
);
5658 ecs
->event_thread
= inferior_thread ();
5659 ecs
->ptid
= inferior_ptid
;
5664 switch_to_thread (child
);
5666 switch_to_thread (parent
);
5668 ecs
->event_thread
= inferior_thread ();
5669 ecs
->ptid
= inferior_ptid
;
5677 process_event_stop_test (ecs
);
5680 case TARGET_WAITKIND_VFORK_DONE
:
5681 /* Done with the shared memory region. Re-insert breakpoints in
5682 the parent, and keep going. */
5684 context_switch (ecs
);
5686 current_inferior ()->thread_waiting_for_vfork_done
= nullptr;
5687 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
5689 if (handle_stop_requested (ecs
))
5692 /* This also takes care of reinserting breakpoints in the
5693 previously locked inferior. */
5697 case TARGET_WAITKIND_EXECD
:
5699 /* Note we can't read registers yet (the stop_pc), because we
5700 don't yet know the inferior's post-exec architecture.
5701 'stop_pc' is explicitly read below instead. */
5702 switch_to_thread_no_regs (ecs
->event_thread
);
5704 /* Do whatever is necessary to the parent branch of the vfork. */
5705 handle_vfork_child_exec_or_exit (1);
5707 /* This causes the eventpoints and symbol table to be reset.
5708 Must do this now, before trying to determine whether to
5710 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
5712 /* In follow_exec we may have deleted the original thread and
5713 created a new one. Make sure that the event thread is the
5714 execd thread for that case (this is a nop otherwise). */
5715 ecs
->event_thread
= inferior_thread ();
5717 ecs
->event_thread
->suspend
.stop_pc
5718 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
5720 ecs
->event_thread
->control
.stop_bpstat
5721 = bpstat_stop_status (get_current_regcache ()->aspace (),
5722 ecs
->event_thread
->suspend
.stop_pc
,
5723 ecs
->event_thread
, &ecs
->ws
);
5725 /* Note that this may be referenced from inside
5726 bpstat_stop_status above, through inferior_has_execd. */
5727 xfree (ecs
->ws
.value
.execd_pathname
);
5728 ecs
->ws
.value
.execd_pathname
= NULL
;
5730 if (handle_stop_requested (ecs
))
5733 /* If no catchpoint triggered for this, then keep going. */
5734 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5736 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5740 process_event_stop_test (ecs
);
5743 /* Be careful not to try to gather much state about a thread
5744 that's in a syscall. It's frequently a losing proposition. */
5745 case TARGET_WAITKIND_SYSCALL_ENTRY
:
5746 /* Getting the current syscall number. */
5747 if (handle_syscall_event (ecs
) == 0)
5748 process_event_stop_test (ecs
);
5751 /* Before examining the threads further, step this thread to
5752 get it entirely out of the syscall. (We get notice of the
5753 event when the thread is just on the verge of exiting a
5754 syscall. Stepping one instruction seems to get it back
5756 case TARGET_WAITKIND_SYSCALL_RETURN
:
5757 if (handle_syscall_event (ecs
) == 0)
5758 process_event_stop_test (ecs
);
5761 case TARGET_WAITKIND_STOPPED
:
5762 handle_signal_stop (ecs
);
5765 case TARGET_WAITKIND_NO_HISTORY
:
5766 /* Reverse execution: target ran out of history info. */
5768 /* Switch to the stopped thread. */
5769 context_switch (ecs
);
5770 infrun_debug_printf ("stopped");
5772 delete_just_stopped_threads_single_step_breakpoints ();
5773 ecs
->event_thread
->suspend
.stop_pc
5774 = regcache_read_pc (get_thread_regcache (inferior_thread ()));
5776 if (handle_stop_requested (ecs
))
5779 gdb::observers::no_history
.notify ();
5785 /* Restart threads back to what they were trying to do back when we
5786 paused them (because of an in-line step-over or vfork, for example).
5787 The EVENT_THREAD thread is ignored (not restarted).
5789 If INF is non-nullptr, only resume threads from INF. */
5792 restart_threads (struct thread_info
*event_thread
, inferior
*inf
)
5794 INFRUN_SCOPED_DEBUG_START_END ("event_thread=%s, inf=%d",
5795 event_thread
->ptid
.to_string ().c_str (),
5796 inf
!= nullptr ? inf
->num
: -1);
5798 /* In case the instruction just stepped spawned a new thread. */
5799 update_thread_list ();
5801 for (thread_info
*tp
: all_non_exited_threads ())
5803 if (inf
!= nullptr && tp
->inf
!= inf
)
5806 if (tp
->inf
->detaching
)
5808 infrun_debug_printf ("restart threads: [%s] inferior detaching",
5809 target_pid_to_str (tp
->ptid
).c_str ());
5813 switch_to_thread_no_regs (tp
);
5815 if (tp
== event_thread
)
5817 infrun_debug_printf ("restart threads: [%s] is event thread",
5818 target_pid_to_str (tp
->ptid
).c_str ());
5822 if (!(tp
->state
== THREAD_RUNNING
|| tp
->control
.in_infcall
))
5824 infrun_debug_printf ("restart threads: [%s] not meant to be running",
5825 target_pid_to_str (tp
->ptid
).c_str ());
5831 infrun_debug_printf ("restart threads: [%s] resumed",
5832 target_pid_to_str (tp
->ptid
).c_str ());
5833 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
5837 if (thread_is_in_step_over_chain (tp
))
5839 infrun_debug_printf ("restart threads: [%s] needs step-over",
5840 target_pid_to_str (tp
->ptid
).c_str ());
5841 gdb_assert (!tp
->resumed
);
5846 if (tp
->suspend
.waitstatus_pending_p
)
5848 infrun_debug_printf ("restart threads: [%s] has pending status",
5849 target_pid_to_str (tp
->ptid
).c_str ());
5854 gdb_assert (!tp
->stop_requested
);
5856 /* If some thread needs to start a step-over at this point, it
5857 should still be in the step-over queue, and thus skipped
5859 if (thread_still_needs_step_over (tp
))
5861 internal_error (__FILE__
, __LINE__
,
5862 "thread [%s] needs a step-over, but not in "
5863 "step-over queue\n",
5864 target_pid_to_str (tp
->ptid
).c_str ());
5867 if (currently_stepping (tp
))
5869 infrun_debug_printf ("restart threads: [%s] was stepping",
5870 target_pid_to_str (tp
->ptid
).c_str ());
5871 keep_going_stepped_thread (tp
);
5875 struct execution_control_state ecss
;
5876 struct execution_control_state
*ecs
= &ecss
;
5878 infrun_debug_printf ("restart threads: [%s] continuing",
5879 target_pid_to_str (tp
->ptid
).c_str ());
5880 reset_ecs (ecs
, tp
);
5881 switch_to_thread (tp
);
5882 keep_going_pass_signal (ecs
);
5887 /* Callback for iterate_over_threads. Find a resumed thread that has
5888 a pending waitstatus. */
5891 resumed_thread_with_pending_status (struct thread_info
*tp
,
5895 && tp
->suspend
.waitstatus_pending_p
);
5898 /* Called when we get an event that may finish an in-line or
5899 out-of-line (displaced stepping) step-over started previously.
5900 Return true if the event is processed and we should go back to the
5901 event loop; false if the caller should continue processing the
5905 finish_step_over (struct execution_control_state
*ecs
)
5907 displaced_step_finish (ecs
->event_thread
,
5908 ecs
->event_thread
->suspend
.stop_signal
);
5910 bool had_step_over_info
= step_over_info_valid_p ();
5912 if (had_step_over_info
)
5914 /* If we're stepping over a breakpoint with all threads locked,
5915 then only the thread that was stepped should be reporting
5917 gdb_assert (ecs
->event_thread
->control
.trap_expected
);
5919 clear_step_over_info ();
5922 if (!target_is_non_stop_p ())
5925 /* Start a new step-over in another thread if there's one that
5929 /* If we were stepping over a breakpoint before, and haven't started
5930 a new in-line step-over sequence, then restart all other threads
5931 (except the event thread). We can't do this in all-stop, as then
5932 e.g., we wouldn't be able to issue any other remote packet until
5933 these other threads stop. */
5934 if (had_step_over_info
&& !step_over_info_valid_p ())
5936 struct thread_info
*pending
;
5938 /* If we only have threads with pending statuses, the restart
5939 below won't restart any thread and so nothing re-inserts the
5940 breakpoint we just stepped over. But we need it inserted
5941 when we later process the pending events, otherwise if
5942 another thread has a pending event for this breakpoint too,
5943 we'd discard its event (because the breakpoint that
5944 originally caused the event was no longer inserted). */
5945 context_switch (ecs
);
5946 insert_breakpoints ();
5948 restart_threads (ecs
->event_thread
);
5950 /* If we have events pending, go through handle_inferior_event
5951 again, picking up a pending event at random. This avoids
5952 thread starvation. */
5954 /* But not if we just stepped over a watchpoint in order to let
5955 the instruction execute so we can evaluate its expression.
5956 The set of watchpoints that triggered is recorded in the
5957 breakpoint objects themselves (see bp->watchpoint_triggered).
5958 If we processed another event first, that other event could
5959 clobber this info. */
5960 if (ecs
->event_thread
->stepping_over_watchpoint
)
5963 pending
= iterate_over_threads (resumed_thread_with_pending_status
,
5965 if (pending
!= NULL
)
5967 struct thread_info
*tp
= ecs
->event_thread
;
5968 struct regcache
*regcache
;
5970 infrun_debug_printf ("found resumed threads with "
5971 "pending events, saving status");
5973 gdb_assert (pending
!= tp
);
5975 /* Record the event thread's event for later. */
5976 save_waitstatus (tp
, &ecs
->ws
);
5977 /* This was cleared early, by handle_inferior_event. Set it
5978 so this pending event is considered by
5982 gdb_assert (!tp
->executing
);
5984 regcache
= get_thread_regcache (tp
);
5985 tp
->suspend
.stop_pc
= regcache_read_pc (regcache
);
5987 infrun_debug_printf ("saved stop_pc=%s for %s "
5988 "(currently_stepping=%d)",
5989 paddress (target_gdbarch (),
5990 tp
->suspend
.stop_pc
),
5991 target_pid_to_str (tp
->ptid
).c_str (),
5992 currently_stepping (tp
));
5994 /* This in-line step-over finished; clear this so we won't
5995 start a new one. This is what handle_signal_stop would
5996 do, if we returned false. */
5997 tp
->stepping_over_breakpoint
= 0;
5999 /* Wake up the event loop again. */
6000 mark_async_event_handler (infrun_async_inferior_event_token
);
6002 prepare_to_wait (ecs
);
6010 /* Come here when the program has stopped with a signal. */
6013 handle_signal_stop (struct execution_control_state
*ecs
)
6015 struct frame_info
*frame
;
6016 struct gdbarch
*gdbarch
;
6017 int stopped_by_watchpoint
;
6018 enum stop_kind stop_soon
;
6021 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
6023 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
6025 /* Do we need to clean up the state of a thread that has
6026 completed a displaced single-step? (Doing so usually affects
6027 the PC, so do it here, before we set stop_pc.) */
6028 if (finish_step_over (ecs
))
6031 /* If we either finished a single-step or hit a breakpoint, but
6032 the user wanted this thread to be stopped, pretend we got a
6033 SIG0 (generic unsignaled stop). */
6034 if (ecs
->event_thread
->stop_requested
6035 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
6036 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6038 ecs
->event_thread
->suspend
.stop_pc
6039 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
6041 context_switch (ecs
);
6043 if (deprecated_context_hook
)
6044 deprecated_context_hook (ecs
->event_thread
->global_num
);
6048 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
6049 struct gdbarch
*reg_gdbarch
= regcache
->arch ();
6051 infrun_debug_printf ("stop_pc=%s",
6052 paddress (reg_gdbarch
,
6053 ecs
->event_thread
->suspend
.stop_pc
));
6054 if (target_stopped_by_watchpoint ())
6058 infrun_debug_printf ("stopped by watchpoint");
6060 if (target_stopped_data_address (current_inferior ()->top_target (),
6062 infrun_debug_printf ("stopped data address=%s",
6063 paddress (reg_gdbarch
, addr
));
6065 infrun_debug_printf ("(no data address available)");
6069 /* This is originated from start_remote(), start_inferior() and
6070 shared libraries hook functions. */
6071 stop_soon
= get_inferior_stop_soon (ecs
);
6072 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
6074 infrun_debug_printf ("quietly stopped");
6075 stop_print_frame
= true;
6080 /* This originates from attach_command(). We need to overwrite
6081 the stop_signal here, because some kernels don't ignore a
6082 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
6083 See more comments in inferior.h. On the other hand, if we
6084 get a non-SIGSTOP, report it to the user - assume the backend
6085 will handle the SIGSTOP if it should show up later.
6087 Also consider that the attach is complete when we see a
6088 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
6089 target extended-remote report it instead of a SIGSTOP
6090 (e.g. gdbserver). We already rely on SIGTRAP being our
6091 signal, so this is no exception.
6093 Also consider that the attach is complete when we see a
6094 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
6095 the target to stop all threads of the inferior, in case the
6096 low level attach operation doesn't stop them implicitly. If
6097 they weren't stopped implicitly, then the stub will report a
6098 GDB_SIGNAL_0, meaning: stopped for no particular reason
6099 other than GDB's request. */
6100 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
6101 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
6102 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6103 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
6105 stop_print_frame
= true;
6107 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6111 /* At this point, get hold of the now-current thread's frame. */
6112 frame
= get_current_frame ();
6113 gdbarch
= get_frame_arch (frame
);
6115 /* Pull the single step breakpoints out of the target. */
6116 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
6118 struct regcache
*regcache
;
6121 regcache
= get_thread_regcache (ecs
->event_thread
);
6122 const address_space
*aspace
= regcache
->aspace ();
6124 pc
= regcache_read_pc (regcache
);
6126 /* However, before doing so, if this single-step breakpoint was
6127 actually for another thread, set this thread up for moving
6129 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
6132 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
6134 infrun_debug_printf ("[%s] hit another thread's single-step "
6136 target_pid_to_str (ecs
->ptid
).c_str ());
6137 ecs
->hit_singlestep_breakpoint
= 1;
6142 infrun_debug_printf ("[%s] hit its single-step breakpoint",
6143 target_pid_to_str (ecs
->ptid
).c_str ());
6146 delete_just_stopped_threads_single_step_breakpoints ();
6148 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6149 && ecs
->event_thread
->control
.trap_expected
6150 && ecs
->event_thread
->stepping_over_watchpoint
)
6151 stopped_by_watchpoint
= 0;
6153 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
6155 /* If necessary, step over this watchpoint. We'll be back to display
6157 if (stopped_by_watchpoint
6158 && (target_have_steppable_watchpoint ()
6159 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
6161 /* At this point, we are stopped at an instruction which has
6162 attempted to write to a piece of memory under control of
6163 a watchpoint. The instruction hasn't actually executed
6164 yet. If we were to evaluate the watchpoint expression
6165 now, we would get the old value, and therefore no change
6166 would seem to have occurred.
6168 In order to make watchpoints work `right', we really need
6169 to complete the memory write, and then evaluate the
6170 watchpoint expression. We do this by single-stepping the
6173 It may not be necessary to disable the watchpoint to step over
6174 it. For example, the PA can (with some kernel cooperation)
6175 single step over a watchpoint without disabling the watchpoint.
6177 It is far more common to need to disable a watchpoint to step
6178 the inferior over it. If we have non-steppable watchpoints,
6179 we must disable the current watchpoint; it's simplest to
6180 disable all watchpoints.
6182 Any breakpoint at PC must also be stepped over -- if there's
6183 one, it will have already triggered before the watchpoint
6184 triggered, and we either already reported it to the user, or
6185 it didn't cause a stop and we called keep_going. In either
6186 case, if there was a breakpoint at PC, we must be trying to
6188 ecs
->event_thread
->stepping_over_watchpoint
= 1;
6193 ecs
->event_thread
->stepping_over_breakpoint
= 0;
6194 ecs
->event_thread
->stepping_over_watchpoint
= 0;
6195 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
6196 ecs
->event_thread
->control
.stop_step
= 0;
6197 stop_print_frame
= true;
6198 stopped_by_random_signal
= 0;
6199 bpstat stop_chain
= NULL
;
6201 /* Hide inlined functions starting here, unless we just performed stepi or
6202 nexti. After stepi and nexti, always show the innermost frame (not any
6203 inline function call sites). */
6204 if (ecs
->event_thread
->control
.step_range_end
!= 1)
6206 const address_space
*aspace
6207 = get_thread_regcache (ecs
->event_thread
)->aspace ();
6209 /* skip_inline_frames is expensive, so we avoid it if we can
6210 determine that the address is one where functions cannot have
6211 been inlined. This improves performance with inferiors that
6212 load a lot of shared libraries, because the solib event
6213 breakpoint is defined as the address of a function (i.e. not
6214 inline). Note that we have to check the previous PC as well
6215 as the current one to catch cases when we have just
6216 single-stepped off a breakpoint prior to reinstating it.
6217 Note that we're assuming that the code we single-step to is
6218 not inline, but that's not definitive: there's nothing
6219 preventing the event breakpoint function from containing
6220 inlined code, and the single-step ending up there. If the
6221 user had set a breakpoint on that inlined code, the missing
6222 skip_inline_frames call would break things. Fortunately
6223 that's an extremely unlikely scenario. */
6224 if (!pc_at_non_inline_function (aspace
,
6225 ecs
->event_thread
->suspend
.stop_pc
,
6227 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6228 && ecs
->event_thread
->control
.trap_expected
6229 && pc_at_non_inline_function (aspace
,
6230 ecs
->event_thread
->prev_pc
,
6233 stop_chain
= build_bpstat_chain (aspace
,
6234 ecs
->event_thread
->suspend
.stop_pc
,
6236 skip_inline_frames (ecs
->event_thread
, stop_chain
);
6238 /* Re-fetch current thread's frame in case that invalidated
6240 frame
= get_current_frame ();
6241 gdbarch
= get_frame_arch (frame
);
6245 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6246 && ecs
->event_thread
->control
.trap_expected
6247 && gdbarch_single_step_through_delay_p (gdbarch
)
6248 && currently_stepping (ecs
->event_thread
))
6250 /* We're trying to step off a breakpoint. Turns out that we're
6251 also on an instruction that needs to be stepped multiple
6252 times before it's been fully executing. E.g., architectures
6253 with a delay slot. It needs to be stepped twice, once for
6254 the instruction and once for the delay slot. */
6255 int step_through_delay
6256 = gdbarch_single_step_through_delay (gdbarch
, frame
);
6258 if (step_through_delay
)
6259 infrun_debug_printf ("step through delay");
6261 if (ecs
->event_thread
->control
.step_range_end
== 0
6262 && step_through_delay
)
6264 /* The user issued a continue when stopped at a breakpoint.
6265 Set up for another trap and get out of here. */
6266 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6270 else if (step_through_delay
)
6272 /* The user issued a step when stopped at a breakpoint.
6273 Maybe we should stop, maybe we should not - the delay
6274 slot *might* correspond to a line of source. In any
6275 case, don't decide that here, just set
6276 ecs->stepping_over_breakpoint, making sure we
6277 single-step again before breakpoints are re-inserted. */
6278 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6282 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
6283 handles this event. */
6284 ecs
->event_thread
->control
.stop_bpstat
6285 = bpstat_stop_status (get_current_regcache ()->aspace (),
6286 ecs
->event_thread
->suspend
.stop_pc
,
6287 ecs
->event_thread
, &ecs
->ws
, stop_chain
);
6289 /* Following in case break condition called a
6291 stop_print_frame
= true;
6293 /* This is where we handle "moribund" watchpoints. Unlike
6294 software breakpoints traps, hardware watchpoint traps are
6295 always distinguishable from random traps. If no high-level
6296 watchpoint is associated with the reported stop data address
6297 anymore, then the bpstat does not explain the signal ---
6298 simply make sure to ignore it if `stopped_by_watchpoint' is
6301 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6302 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
6304 && stopped_by_watchpoint
)
6306 infrun_debug_printf ("no user watchpoint explains watchpoint SIGTRAP, "
6310 /* NOTE: cagney/2003-03-29: These checks for a random signal
6311 at one stage in the past included checks for an inferior
6312 function call's call dummy's return breakpoint. The original
6313 comment, that went with the test, read:
6315 ``End of a stack dummy. Some systems (e.g. Sony news) give
6316 another signal besides SIGTRAP, so check here as well as
6319 If someone ever tries to get call dummys on a
6320 non-executable stack to work (where the target would stop
6321 with something like a SIGSEGV), then those tests might need
6322 to be re-instated. Given, however, that the tests were only
6323 enabled when momentary breakpoints were not being used, I
6324 suspect that it won't be the case.
6326 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
6327 be necessary for call dummies on a non-executable stack on
6330 /* See if the breakpoints module can explain the signal. */
6332 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
6333 ecs
->event_thread
->suspend
.stop_signal
);
6335 /* Maybe this was a trap for a software breakpoint that has since
6337 if (random_signal
&& target_stopped_by_sw_breakpoint ())
6339 if (gdbarch_program_breakpoint_here_p (gdbarch
,
6340 ecs
->event_thread
->suspend
.stop_pc
))
6342 struct regcache
*regcache
;
6345 /* Re-adjust PC to what the program would see if GDB was not
6347 regcache
= get_thread_regcache (ecs
->event_thread
);
6348 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
6351 gdb::optional
<scoped_restore_tmpl
<int>>
6352 restore_operation_disable
;
6354 if (record_full_is_used ())
6355 restore_operation_disable
.emplace
6356 (record_full_gdb_operation_disable_set ());
6358 regcache_write_pc (regcache
,
6359 ecs
->event_thread
->suspend
.stop_pc
+ decr_pc
);
6364 /* A delayed software breakpoint event. Ignore the trap. */
6365 infrun_debug_printf ("delayed software breakpoint trap, ignoring");
6370 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
6371 has since been removed. */
6372 if (random_signal
&& target_stopped_by_hw_breakpoint ())
6374 /* A delayed hardware breakpoint event. Ignore the trap. */
6375 infrun_debug_printf ("delayed hardware breakpoint/watchpoint "
6380 /* If not, perhaps stepping/nexting can. */
6382 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6383 && currently_stepping (ecs
->event_thread
));
6385 /* Perhaps the thread hit a single-step breakpoint of _another_
6386 thread. Single-step breakpoints are transparent to the
6387 breakpoints module. */
6389 random_signal
= !ecs
->hit_singlestep_breakpoint
;
6391 /* No? Perhaps we got a moribund watchpoint. */
6393 random_signal
= !stopped_by_watchpoint
;
6395 /* Always stop if the user explicitly requested this thread to
6397 if (ecs
->event_thread
->stop_requested
)
6400 infrun_debug_printf ("user-requested stop");
6403 /* For the program's own signals, act according to
6404 the signal handling tables. */
6408 /* Signal not for debugging purposes. */
6409 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
6411 infrun_debug_printf ("random signal (%s)",
6412 gdb_signal_to_symbol_string (stop_signal
));
6414 stopped_by_random_signal
= 1;
6416 /* Always stop on signals if we're either just gaining control
6417 of the program, or the user explicitly requested this thread
6418 to remain stopped. */
6419 if (stop_soon
!= NO_STOP_QUIETLY
6420 || ecs
->event_thread
->stop_requested
6421 || signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
))
6427 /* Notify observers the signal has "handle print" set. Note we
6428 returned early above if stopping; normal_stop handles the
6429 printing in that case. */
6430 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
6432 /* The signal table tells us to print about this signal. */
6433 target_terminal::ours_for_output ();
6434 gdb::observers::signal_received
.notify (ecs
->event_thread
->suspend
.stop_signal
);
6435 target_terminal::inferior ();
6438 /* Clear the signal if it should not be passed. */
6439 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
6440 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6442 if (ecs
->event_thread
->prev_pc
== ecs
->event_thread
->suspend
.stop_pc
6443 && ecs
->event_thread
->control
.trap_expected
6444 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6446 /* We were just starting a new sequence, attempting to
6447 single-step off of a breakpoint and expecting a SIGTRAP.
6448 Instead this signal arrives. This signal will take us out
6449 of the stepping range so GDB needs to remember to, when
6450 the signal handler returns, resume stepping off that
6452 /* To simplify things, "continue" is forced to use the same
6453 code paths as single-step - set a breakpoint at the
6454 signal return address and then, once hit, step off that
6456 infrun_debug_printf ("signal arrived while stepping over breakpoint");
6458 insert_hp_step_resume_breakpoint_at_frame (frame
);
6459 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6460 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6461 ecs
->event_thread
->control
.trap_expected
= 0;
6463 /* If we were nexting/stepping some other thread, switch to
6464 it, so that we don't continue it, losing control. */
6465 if (!switch_back_to_stepped_thread (ecs
))
6470 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
6471 && (pc_in_thread_step_range (ecs
->event_thread
->suspend
.stop_pc
,
6473 || ecs
->event_thread
->control
.step_range_end
== 1)
6474 && frame_id_eq (get_stack_frame_id (frame
),
6475 ecs
->event_thread
->control
.step_stack_frame_id
)
6476 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6478 /* The inferior is about to take a signal that will take it
6479 out of the single step range. Set a breakpoint at the
6480 current PC (which is presumably where the signal handler
6481 will eventually return) and then allow the inferior to
6484 Note that this is only needed for a signal delivered
6485 while in the single-step range. Nested signals aren't a
6486 problem as they eventually all return. */
6487 infrun_debug_printf ("signal may take us out of single-step range");
6489 clear_step_over_info ();
6490 insert_hp_step_resume_breakpoint_at_frame (frame
);
6491 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6492 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6493 ecs
->event_thread
->control
.trap_expected
= 0;
6498 /* Note: step_resume_breakpoint may be non-NULL. This occurs
6499 when either there's a nested signal, or when there's a
6500 pending signal enabled just as the signal handler returns
6501 (leaving the inferior at the step-resume-breakpoint without
6502 actually executing it). Either way continue until the
6503 breakpoint is really hit. */
6505 if (!switch_back_to_stepped_thread (ecs
))
6507 infrun_debug_printf ("random signal, keep going");
6514 process_event_stop_test (ecs
);
6517 /* Come here when we've got some debug event / signal we can explain
6518 (IOW, not a random signal), and test whether it should cause a
6519 stop, or whether we should resume the inferior (transparently).
6520 E.g., could be a breakpoint whose condition evaluates false; we
6521 could be still stepping within the line; etc. */
6524 process_event_stop_test (struct execution_control_state
*ecs
)
6526 struct symtab_and_line stop_pc_sal
;
6527 struct frame_info
*frame
;
6528 struct gdbarch
*gdbarch
;
6529 CORE_ADDR jmp_buf_pc
;
6530 struct bpstat_what what
;
6532 /* Handle cases caused by hitting a breakpoint. */
6534 frame
= get_current_frame ();
6535 gdbarch
= get_frame_arch (frame
);
6537 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
6539 if (what
.call_dummy
)
6541 stop_stack_dummy
= what
.call_dummy
;
6544 /* A few breakpoint types have callbacks associated (e.g.,
6545 bp_jit_event). Run them now. */
6546 bpstat_run_callbacks (ecs
->event_thread
->control
.stop_bpstat
);
6548 /* If we hit an internal event that triggers symbol changes, the
6549 current frame will be invalidated within bpstat_what (e.g., if we
6550 hit an internal solib event). Re-fetch it. */
6551 frame
= get_current_frame ();
6552 gdbarch
= get_frame_arch (frame
);
6554 switch (what
.main_action
)
6556 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
6557 /* If we hit the breakpoint at longjmp while stepping, we
6558 install a momentary breakpoint at the target of the
6561 infrun_debug_printf ("BPSTAT_WHAT_SET_LONGJMP_RESUME");
6563 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6565 if (what
.is_longjmp
)
6567 struct value
*arg_value
;
6569 /* If we set the longjmp breakpoint via a SystemTap probe,
6570 then use it to extract the arguments. The destination PC
6571 is the third argument to the probe. */
6572 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
6575 jmp_buf_pc
= value_as_address (arg_value
);
6576 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
6578 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
6579 || !gdbarch_get_longjmp_target (gdbarch
,
6580 frame
, &jmp_buf_pc
))
6582 infrun_debug_printf ("BPSTAT_WHAT_SET_LONGJMP_RESUME "
6583 "(!gdbarch_get_longjmp_target)");
6588 /* Insert a breakpoint at resume address. */
6589 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
6592 check_exception_resume (ecs
, frame
);
6596 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
6598 struct frame_info
*init_frame
;
6600 /* There are several cases to consider.
6602 1. The initiating frame no longer exists. In this case we
6603 must stop, because the exception or longjmp has gone too
6606 2. The initiating frame exists, and is the same as the
6607 current frame. We stop, because the exception or longjmp
6610 3. The initiating frame exists and is different from the
6611 current frame. This means the exception or longjmp has
6612 been caught beneath the initiating frame, so keep going.
6614 4. longjmp breakpoint has been placed just to protect
6615 against stale dummy frames and user is not interested in
6616 stopping around longjmps. */
6618 infrun_debug_printf ("BPSTAT_WHAT_CLEAR_LONGJMP_RESUME");
6620 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
6622 delete_exception_resume_breakpoint (ecs
->event_thread
);
6624 if (what
.is_longjmp
)
6626 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
6628 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
6636 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
6640 struct frame_id current_id
6641 = get_frame_id (get_current_frame ());
6642 if (frame_id_eq (current_id
,
6643 ecs
->event_thread
->initiating_frame
))
6645 /* Case 2. Fall through. */
6655 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6657 delete_step_resume_breakpoint (ecs
->event_thread
);
6659 end_stepping_range (ecs
);
6663 case BPSTAT_WHAT_SINGLE
:
6664 infrun_debug_printf ("BPSTAT_WHAT_SINGLE");
6665 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6666 /* Still need to check other stuff, at least the case where we
6667 are stepping and step out of the right range. */
6670 case BPSTAT_WHAT_STEP_RESUME
:
6671 infrun_debug_printf ("BPSTAT_WHAT_STEP_RESUME");
6673 delete_step_resume_breakpoint (ecs
->event_thread
);
6674 if (ecs
->event_thread
->control
.proceed_to_finish
6675 && execution_direction
== EXEC_REVERSE
)
6677 struct thread_info
*tp
= ecs
->event_thread
;
6679 /* We are finishing a function in reverse, and just hit the
6680 step-resume breakpoint at the start address of the
6681 function, and we're almost there -- just need to back up
6682 by one more single-step, which should take us back to the
6684 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
6688 fill_in_stop_func (gdbarch
, ecs
);
6689 if (ecs
->event_thread
->suspend
.stop_pc
== ecs
->stop_func_start
6690 && execution_direction
== EXEC_REVERSE
)
6692 /* We are stepping over a function call in reverse, and just
6693 hit the step-resume breakpoint at the start address of
6694 the function. Go back to single-stepping, which should
6695 take us back to the function call. */
6696 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6702 case BPSTAT_WHAT_STOP_NOISY
:
6703 infrun_debug_printf ("BPSTAT_WHAT_STOP_NOISY");
6704 stop_print_frame
= true;
6706 /* Assume the thread stopped for a breakpoint. We'll still check
6707 whether a/the breakpoint is there when the thread is next
6709 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6714 case BPSTAT_WHAT_STOP_SILENT
:
6715 infrun_debug_printf ("BPSTAT_WHAT_STOP_SILENT");
6716 stop_print_frame
= false;
6718 /* Assume the thread stopped for a breakpoint. We'll still check
6719 whether a/the breakpoint is there when the thread is next
6721 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6725 case BPSTAT_WHAT_HP_STEP_RESUME
:
6726 infrun_debug_printf ("BPSTAT_WHAT_HP_STEP_RESUME");
6728 delete_step_resume_breakpoint (ecs
->event_thread
);
6729 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
6731 /* Back when the step-resume breakpoint was inserted, we
6732 were trying to single-step off a breakpoint. Go back to
6734 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6735 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6741 case BPSTAT_WHAT_KEEP_CHECKING
:
6745 /* If we stepped a permanent breakpoint and we had a high priority
6746 step-resume breakpoint for the address we stepped, but we didn't
6747 hit it, then we must have stepped into the signal handler. The
6748 step-resume was only necessary to catch the case of _not_
6749 stepping into the handler, so delete it, and fall through to
6750 checking whether the step finished. */
6751 if (ecs
->event_thread
->stepped_breakpoint
)
6753 struct breakpoint
*sr_bp
6754 = ecs
->event_thread
->control
.step_resume_breakpoint
;
6757 && sr_bp
->loc
->permanent
6758 && sr_bp
->type
== bp_hp_step_resume
6759 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
6761 infrun_debug_printf ("stepped permanent breakpoint, stopped in handler");
6762 delete_step_resume_breakpoint (ecs
->event_thread
);
6763 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6767 /* We come here if we hit a breakpoint but should not stop for it.
6768 Possibly we also were stepping and should stop for that. So fall
6769 through and test for stepping. But, if not stepping, do not
6772 /* In all-stop mode, if we're currently stepping but have stopped in
6773 some other thread, we need to switch back to the stepped thread. */
6774 if (switch_back_to_stepped_thread (ecs
))
6777 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
6779 infrun_debug_printf ("step-resume breakpoint is inserted");
6781 /* Having a step-resume breakpoint overrides anything
6782 else having to do with stepping commands until
6783 that breakpoint is reached. */
6788 if (ecs
->event_thread
->control
.step_range_end
== 0)
6790 infrun_debug_printf ("no stepping, continue");
6791 /* Likewise if we aren't even stepping. */
6796 /* Re-fetch current thread's frame in case the code above caused
6797 the frame cache to be re-initialized, making our FRAME variable
6798 a dangling pointer. */
6799 frame
= get_current_frame ();
6800 gdbarch
= get_frame_arch (frame
);
6801 fill_in_stop_func (gdbarch
, ecs
);
6803 /* If stepping through a line, keep going if still within it.
6805 Note that step_range_end is the address of the first instruction
6806 beyond the step range, and NOT the address of the last instruction
6809 Note also that during reverse execution, we may be stepping
6810 through a function epilogue and therefore must detect when
6811 the current-frame changes in the middle of a line. */
6813 if (pc_in_thread_step_range (ecs
->event_thread
->suspend
.stop_pc
,
6815 && (execution_direction
!= EXEC_REVERSE
6816 || frame_id_eq (get_frame_id (frame
),
6817 ecs
->event_thread
->control
.step_frame_id
)))
6820 ("stepping inside range [%s-%s]",
6821 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
6822 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
6824 /* Tentatively re-enable range stepping; `resume' disables it if
6825 necessary (e.g., if we're stepping over a breakpoint or we
6826 have software watchpoints). */
6827 ecs
->event_thread
->control
.may_range_step
= 1;
6829 /* When stepping backward, stop at beginning of line range
6830 (unless it's the function entry point, in which case
6831 keep going back to the call point). */
6832 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6833 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
6834 && stop_pc
!= ecs
->stop_func_start
6835 && execution_direction
== EXEC_REVERSE
)
6836 end_stepping_range (ecs
);
6843 /* We stepped out of the stepping range. */
6845 /* If we are stepping at the source level and entered the runtime
6846 loader dynamic symbol resolution code...
6848 EXEC_FORWARD: we keep on single stepping until we exit the run
6849 time loader code and reach the callee's address.
6851 EXEC_REVERSE: we've already executed the callee (backward), and
6852 the runtime loader code is handled just like any other
6853 undebuggable function call. Now we need only keep stepping
6854 backward through the trampoline code, and that's handled further
6855 down, so there is nothing for us to do here. */
6857 if (execution_direction
!= EXEC_REVERSE
6858 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6859 && in_solib_dynsym_resolve_code (ecs
->event_thread
->suspend
.stop_pc
))
6861 CORE_ADDR pc_after_resolver
=
6862 gdbarch_skip_solib_resolver (gdbarch
,
6863 ecs
->event_thread
->suspend
.stop_pc
);
6865 infrun_debug_printf ("stepped into dynsym resolve code");
6867 if (pc_after_resolver
)
6869 /* Set up a step-resume breakpoint at the address
6870 indicated by SKIP_SOLIB_RESOLVER. */
6871 symtab_and_line sr_sal
;
6872 sr_sal
.pc
= pc_after_resolver
;
6873 sr_sal
.pspace
= get_frame_program_space (frame
);
6875 insert_step_resume_breakpoint_at_sal (gdbarch
,
6876 sr_sal
, null_frame_id
);
6883 /* Step through an indirect branch thunk. */
6884 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6885 && gdbarch_in_indirect_branch_thunk (gdbarch
,
6886 ecs
->event_thread
->suspend
.stop_pc
))
6888 infrun_debug_printf ("stepped into indirect branch thunk");
6893 if (ecs
->event_thread
->control
.step_range_end
!= 1
6894 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6895 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6896 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
6898 infrun_debug_printf ("stepped into signal trampoline");
6899 /* The inferior, while doing a "step" or "next", has ended up in
6900 a signal trampoline (either by a signal being delivered or by
6901 the signal handler returning). Just single-step until the
6902 inferior leaves the trampoline (either by calling the handler
6908 /* If we're in the return path from a shared library trampoline,
6909 we want to proceed through the trampoline when stepping. */
6910 /* macro/2012-04-25: This needs to come before the subroutine
6911 call check below as on some targets return trampolines look
6912 like subroutine calls (MIPS16 return thunks). */
6913 if (gdbarch_in_solib_return_trampoline (gdbarch
,
6914 ecs
->event_thread
->suspend
.stop_pc
,
6915 ecs
->stop_func_name
)
6916 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6918 /* Determine where this trampoline returns. */
6919 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6920 CORE_ADDR real_stop_pc
6921 = gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6923 infrun_debug_printf ("stepped into solib return tramp");
6925 /* Only proceed through if we know where it's going. */
6928 /* And put the step-breakpoint there and go until there. */
6929 symtab_and_line sr_sal
;
6930 sr_sal
.pc
= real_stop_pc
;
6931 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6932 sr_sal
.pspace
= get_frame_program_space (frame
);
6934 /* Do not specify what the fp should be when we stop since
6935 on some machines the prologue is where the new fp value
6937 insert_step_resume_breakpoint_at_sal (gdbarch
,
6938 sr_sal
, null_frame_id
);
6940 /* Restart without fiddling with the step ranges or
6947 /* Check for subroutine calls. The check for the current frame
6948 equalling the step ID is not necessary - the check of the
6949 previous frame's ID is sufficient - but it is a common case and
6950 cheaper than checking the previous frame's ID.
6952 NOTE: frame_id_eq will never report two invalid frame IDs as
6953 being equal, so to get into this block, both the current and
6954 previous frame must have valid frame IDs. */
6955 /* The outer_frame_id check is a heuristic to detect stepping
6956 through startup code. If we step over an instruction which
6957 sets the stack pointer from an invalid value to a valid value,
6958 we may detect that as a subroutine call from the mythical
6959 "outermost" function. This could be fixed by marking
6960 outermost frames as !stack_p,code_p,special_p. Then the
6961 initial outermost frame, before sp was valid, would
6962 have code_addr == &_start. See the comment in frame_id_eq
6964 if (!frame_id_eq (get_stack_frame_id (frame
),
6965 ecs
->event_thread
->control
.step_stack_frame_id
)
6966 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6967 ecs
->event_thread
->control
.step_stack_frame_id
)
6968 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
6970 || (ecs
->event_thread
->control
.step_start_function
6971 != find_pc_function (ecs
->event_thread
->suspend
.stop_pc
)))))
6973 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6974 CORE_ADDR real_stop_pc
;
6976 infrun_debug_printf ("stepped into subroutine");
6978 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
6980 /* I presume that step_over_calls is only 0 when we're
6981 supposed to be stepping at the assembly language level
6982 ("stepi"). Just stop. */
6983 /* And this works the same backward as frontward. MVS */
6984 end_stepping_range (ecs
);
6988 /* Reverse stepping through solib trampolines. */
6990 if (execution_direction
== EXEC_REVERSE
6991 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6992 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6993 || (ecs
->stop_func_start
== 0
6994 && in_solib_dynsym_resolve_code (stop_pc
))))
6996 /* Any solib trampoline code can be handled in reverse
6997 by simply continuing to single-step. We have already
6998 executed the solib function (backwards), and a few
6999 steps will take us back through the trampoline to the
7005 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
7007 /* We're doing a "next".
7009 Normal (forward) execution: set a breakpoint at the
7010 callee's return address (the address at which the caller
7013 Reverse (backward) execution. set the step-resume
7014 breakpoint at the start of the function that we just
7015 stepped into (backwards), and continue to there. When we
7016 get there, we'll need to single-step back to the caller. */
7018 if (execution_direction
== EXEC_REVERSE
)
7020 /* If we're already at the start of the function, we've either
7021 just stepped backward into a single instruction function,
7022 or stepped back out of a signal handler to the first instruction
7023 of the function. Just keep going, which will single-step back
7025 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
7027 /* Normal function call return (static or dynamic). */
7028 symtab_and_line sr_sal
;
7029 sr_sal
.pc
= ecs
->stop_func_start
;
7030 sr_sal
.pspace
= get_frame_program_space (frame
);
7031 insert_step_resume_breakpoint_at_sal (gdbarch
,
7032 sr_sal
, null_frame_id
);
7036 insert_step_resume_breakpoint_at_caller (frame
);
7042 /* If we are in a function call trampoline (a stub between the
7043 calling routine and the real function), locate the real
7044 function. That's what tells us (a) whether we want to step
7045 into it at all, and (b) what prologue we want to run to the
7046 end of, if we do step into it. */
7047 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
7048 if (real_stop_pc
== 0)
7049 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
7050 if (real_stop_pc
!= 0)
7051 ecs
->stop_func_start
= real_stop_pc
;
7053 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
7055 symtab_and_line sr_sal
;
7056 sr_sal
.pc
= ecs
->stop_func_start
;
7057 sr_sal
.pspace
= get_frame_program_space (frame
);
7059 insert_step_resume_breakpoint_at_sal (gdbarch
,
7060 sr_sal
, null_frame_id
);
7065 /* If we have line number information for the function we are
7066 thinking of stepping into and the function isn't on the skip
7069 If there are several symtabs at that PC (e.g. with include
7070 files), just want to know whether *any* of them have line
7071 numbers. find_pc_line handles this. */
7073 struct symtab_and_line tmp_sal
;
7075 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7076 if (tmp_sal
.line
!= 0
7077 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
7079 && !inline_frame_is_marked_for_skip (true, ecs
->event_thread
))
7081 if (execution_direction
== EXEC_REVERSE
)
7082 handle_step_into_function_backward (gdbarch
, ecs
);
7084 handle_step_into_function (gdbarch
, ecs
);
7089 /* If we have no line number and the step-stop-if-no-debug is
7090 set, we stop the step so that the user has a chance to switch
7091 in assembly mode. */
7092 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
7093 && step_stop_if_no_debug
)
7095 end_stepping_range (ecs
);
7099 if (execution_direction
== EXEC_REVERSE
)
7101 /* If we're already at the start of the function, we've either just
7102 stepped backward into a single instruction function without line
7103 number info, or stepped back out of a signal handler to the first
7104 instruction of the function without line number info. Just keep
7105 going, which will single-step back to the caller. */
7106 if (ecs
->stop_func_start
!= stop_pc
)
7108 /* Set a breakpoint at callee's start address.
7109 From there we can step once and be back in the caller. */
7110 symtab_and_line sr_sal
;
7111 sr_sal
.pc
= ecs
->stop_func_start
;
7112 sr_sal
.pspace
= get_frame_program_space (frame
);
7113 insert_step_resume_breakpoint_at_sal (gdbarch
,
7114 sr_sal
, null_frame_id
);
7118 /* Set a breakpoint at callee's return address (the address
7119 at which the caller will resume). */
7120 insert_step_resume_breakpoint_at_caller (frame
);
7126 /* Reverse stepping through solib trampolines. */
7128 if (execution_direction
== EXEC_REVERSE
7129 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
7131 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
7133 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
7134 || (ecs
->stop_func_start
== 0
7135 && in_solib_dynsym_resolve_code (stop_pc
)))
7137 /* Any solib trampoline code can be handled in reverse
7138 by simply continuing to single-step. We have already
7139 executed the solib function (backwards), and a few
7140 steps will take us back through the trampoline to the
7145 else if (in_solib_dynsym_resolve_code (stop_pc
))
7147 /* Stepped backward into the solib dynsym resolver.
7148 Set a breakpoint at its start and continue, then
7149 one more step will take us out. */
7150 symtab_and_line sr_sal
;
7151 sr_sal
.pc
= ecs
->stop_func_start
;
7152 sr_sal
.pspace
= get_frame_program_space (frame
);
7153 insert_step_resume_breakpoint_at_sal (gdbarch
,
7154 sr_sal
, null_frame_id
);
7160 /* This always returns the sal for the inner-most frame when we are in a
7161 stack of inlined frames, even if GDB actually believes that it is in a
7162 more outer frame. This is checked for below by calls to
7163 inline_skipped_frames. */
7164 stop_pc_sal
= find_pc_line (ecs
->event_thread
->suspend
.stop_pc
, 0);
7166 /* NOTE: tausq/2004-05-24: This if block used to be done before all
7167 the trampoline processing logic, however, there are some trampolines
7168 that have no names, so we should do trampoline handling first. */
7169 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
7170 && ecs
->stop_func_name
== NULL
7171 && stop_pc_sal
.line
== 0)
7173 infrun_debug_printf ("stepped into undebuggable function");
7175 /* The inferior just stepped into, or returned to, an
7176 undebuggable function (where there is no debugging information
7177 and no line number corresponding to the address where the
7178 inferior stopped). Since we want to skip this kind of code,
7179 we keep going until the inferior returns from this
7180 function - unless the user has asked us not to (via
7181 set step-mode) or we no longer know how to get back
7182 to the call site. */
7183 if (step_stop_if_no_debug
7184 || !frame_id_p (frame_unwind_caller_id (frame
)))
7186 /* If we have no line number and the step-stop-if-no-debug
7187 is set, we stop the step so that the user has a chance to
7188 switch in assembly mode. */
7189 end_stepping_range (ecs
);
7194 /* Set a breakpoint at callee's return address (the address
7195 at which the caller will resume). */
7196 insert_step_resume_breakpoint_at_caller (frame
);
7202 if (ecs
->event_thread
->control
.step_range_end
== 1)
7204 /* It is stepi or nexti. We always want to stop stepping after
7206 infrun_debug_printf ("stepi/nexti");
7207 end_stepping_range (ecs
);
7211 if (stop_pc_sal
.line
== 0)
7213 /* We have no line number information. That means to stop
7214 stepping (does this always happen right after one instruction,
7215 when we do "s" in a function with no line numbers,
7216 or can this happen as a result of a return or longjmp?). */
7217 infrun_debug_printf ("line number info");
7218 end_stepping_range (ecs
);
7222 /* Look for "calls" to inlined functions, part one. If the inline
7223 frame machinery detected some skipped call sites, we have entered
7224 a new inline function. */
7226 if (frame_id_eq (get_frame_id (get_current_frame ()),
7227 ecs
->event_thread
->control
.step_frame_id
)
7228 && inline_skipped_frames (ecs
->event_thread
))
7230 infrun_debug_printf ("stepped into inlined function");
7232 symtab_and_line call_sal
= find_frame_sal (get_current_frame ());
7234 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
7236 /* For "step", we're going to stop. But if the call site
7237 for this inlined function is on the same source line as
7238 we were previously stepping, go down into the function
7239 first. Otherwise stop at the call site. */
7241 if (call_sal
.line
== ecs
->event_thread
->current_line
7242 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
7244 step_into_inline_frame (ecs
->event_thread
);
7245 if (inline_frame_is_marked_for_skip (false, ecs
->event_thread
))
7252 end_stepping_range (ecs
);
7257 /* For "next", we should stop at the call site if it is on a
7258 different source line. Otherwise continue through the
7259 inlined function. */
7260 if (call_sal
.line
== ecs
->event_thread
->current_line
7261 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
7264 end_stepping_range (ecs
);
7269 /* Look for "calls" to inlined functions, part two. If we are still
7270 in the same real function we were stepping through, but we have
7271 to go further up to find the exact frame ID, we are stepping
7272 through a more inlined call beyond its call site. */
7274 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
7275 && !frame_id_eq (get_frame_id (get_current_frame ()),
7276 ecs
->event_thread
->control
.step_frame_id
)
7277 && stepped_in_from (get_current_frame (),
7278 ecs
->event_thread
->control
.step_frame_id
))
7280 infrun_debug_printf ("stepping through inlined function");
7282 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
7283 || inline_frame_is_marked_for_skip (false, ecs
->event_thread
))
7286 end_stepping_range (ecs
);
7290 bool refresh_step_info
= true;
7291 if ((ecs
->event_thread
->suspend
.stop_pc
== stop_pc_sal
.pc
)
7292 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
7293 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
7295 /* We are at a different line. */
7297 if (stop_pc_sal
.is_stmt
)
7299 /* We are at the start of a statement.
7301 So stop. Note that we don't stop if we step into the middle of a
7302 statement. That is said to make things like for (;;) statements
7304 infrun_debug_printf ("stepped to a different line");
7305 end_stepping_range (ecs
);
7308 else if (frame_id_eq (get_frame_id (get_current_frame ()),
7309 ecs
->event_thread
->control
.step_frame_id
))
7311 /* We are not at the start of a statement, and we have not changed
7314 We ignore this line table entry, and continue stepping forward,
7315 looking for a better place to stop. */
7316 refresh_step_info
= false;
7317 infrun_debug_printf ("stepped to a different line, but "
7318 "it's not the start of a statement");
7322 /* We are not the start of a statement, and we have changed frame.
7324 We ignore this line table entry, and continue stepping forward,
7325 looking for a better place to stop. Keep refresh_step_info at
7326 true to note that the frame has changed, but ignore the line
7327 number to make sure we don't ignore a subsequent entry with the
7328 same line number. */
7329 stop_pc_sal
.line
= 0;
7330 infrun_debug_printf ("stepped to a different frame, but "
7331 "it's not the start of a statement");
7335 /* We aren't done stepping.
7337 Optimize by setting the stepping range to the line.
7338 (We might not be in the original line, but if we entered a
7339 new line in mid-statement, we continue stepping. This makes
7340 things like for(;;) statements work better.)
7342 If we entered a SAL that indicates a non-statement line table entry,
7343 then we update the stepping range, but we don't update the step info,
7344 which includes things like the line number we are stepping away from.
7345 This means we will stop when we find a line table entry that is marked
7346 as is-statement, even if it matches the non-statement one we just
7349 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
7350 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
7351 ecs
->event_thread
->control
.may_range_step
= 1;
7352 if (refresh_step_info
)
7353 set_step_info (ecs
->event_thread
, frame
, stop_pc_sal
);
7355 infrun_debug_printf ("keep going");
7359 static bool restart_stepped_thread (process_stratum_target
*resume_target
,
7360 ptid_t resume_ptid
);
7362 /* In all-stop mode, if we're currently stepping but have stopped in
7363 some other thread, we may need to switch back to the stepped
7364 thread. Returns true we set the inferior running, false if we left
7365 it stopped (and the event needs further processing). */
7368 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
7370 if (!target_is_non_stop_p ())
7372 /* If any thread is blocked on some internal breakpoint, and we
7373 simply need to step over that breakpoint to get it going
7374 again, do that first. */
7376 /* However, if we see an event for the stepping thread, then we
7377 know all other threads have been moved past their breakpoints
7378 already. Let the caller check whether the step is finished,
7379 etc., before deciding to move it past a breakpoint. */
7380 if (ecs
->event_thread
->control
.step_range_end
!= 0)
7383 /* Check if the current thread is blocked on an incomplete
7384 step-over, interrupted by a random signal. */
7385 if (ecs
->event_thread
->control
.trap_expected
7386 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
7389 ("need to finish step-over of [%s]",
7390 target_pid_to_str (ecs
->event_thread
->ptid
).c_str ());
7395 /* Check if the current thread is blocked by a single-step
7396 breakpoint of another thread. */
7397 if (ecs
->hit_singlestep_breakpoint
)
7399 infrun_debug_printf ("need to step [%s] over single-step breakpoint",
7400 target_pid_to_str (ecs
->ptid
).c_str ());
7405 /* If this thread needs yet another step-over (e.g., stepping
7406 through a delay slot), do it first before moving on to
7408 if (thread_still_needs_step_over (ecs
->event_thread
))
7411 ("thread [%s] still needs step-over",
7412 target_pid_to_str (ecs
->event_thread
->ptid
).c_str ());
7417 /* If scheduler locking applies even if not stepping, there's no
7418 need to walk over threads. Above we've checked whether the
7419 current thread is stepping. If some other thread not the
7420 event thread is stepping, then it must be that scheduler
7421 locking is not in effect. */
7422 if (schedlock_applies (ecs
->event_thread
))
7425 /* Otherwise, we no longer expect a trap in the current thread.
7426 Clear the trap_expected flag before switching back -- this is
7427 what keep_going does as well, if we call it. */
7428 ecs
->event_thread
->control
.trap_expected
= 0;
7430 /* Likewise, clear the signal if it should not be passed. */
7431 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7432 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7434 if (restart_stepped_thread (ecs
->target
, ecs
->ptid
))
7436 prepare_to_wait (ecs
);
7440 switch_to_thread (ecs
->event_thread
);
7446 /* Look for the thread that was stepping, and resume it.
7447 RESUME_TARGET / RESUME_PTID indicate the set of threads the caller
7448 is resuming. Return true if a thread was started, false
7452 restart_stepped_thread (process_stratum_target
*resume_target
,
7455 /* Do all pending step-overs before actually proceeding with
7457 if (start_step_over ())
7460 for (thread_info
*tp
: all_threads_safe ())
7462 if (tp
->state
== THREAD_EXITED
)
7465 if (tp
->suspend
.waitstatus_pending_p
)
7468 /* Ignore threads of processes the caller is not
7471 && (tp
->inf
->process_target () != resume_target
7472 || tp
->inf
->pid
!= resume_ptid
.pid ()))
7475 if (tp
->control
.trap_expected
)
7477 infrun_debug_printf ("switching back to stepped thread (step-over)");
7479 if (keep_going_stepped_thread (tp
))
7484 for (thread_info
*tp
: all_threads_safe ())
7486 if (tp
->state
== THREAD_EXITED
)
7489 if (tp
->suspend
.waitstatus_pending_p
)
7492 /* Ignore threads of processes the caller is not
7495 && (tp
->inf
->process_target () != resume_target
7496 || tp
->inf
->pid
!= resume_ptid
.pid ()))
7499 /* Did we find the stepping thread? */
7500 if (tp
->control
.step_range_end
)
7502 infrun_debug_printf ("switching back to stepped thread (stepping)");
7504 if (keep_going_stepped_thread (tp
))
7515 restart_after_all_stop_detach (process_stratum_target
*proc_target
)
7517 /* Note we don't check target_is_non_stop_p() here, because the
7518 current inferior may no longer have a process_stratum target
7519 pushed, as we just detached. */
7521 /* See if we have a THREAD_RUNNING thread that need to be
7522 re-resumed. If we have any thread that is already executing,
7523 then we don't need to resume the target -- it is already been
7524 resumed. With the remote target (in all-stop), it's even
7525 impossible to issue another resumption if the target is already
7526 resumed, until the target reports a stop. */
7527 for (thread_info
*thr
: all_threads (proc_target
))
7529 if (thr
->state
!= THREAD_RUNNING
)
7532 /* If we have any thread that is already executing, then we
7533 don't need to resume the target -- it is already been
7538 /* If we have a pending event to process, skip resuming the
7539 target and go straight to processing it. */
7540 if (thr
->resumed
&& thr
->suspend
.waitstatus_pending_p
)
7544 /* Alright, we need to re-resume the target. If a thread was
7545 stepping, we need to restart it stepping. */
7546 if (restart_stepped_thread (proc_target
, minus_one_ptid
))
7549 /* Otherwise, find the first THREAD_RUNNING thread and resume
7551 for (thread_info
*thr
: all_threads (proc_target
))
7553 if (thr
->state
!= THREAD_RUNNING
)
7556 execution_control_state ecs
;
7557 reset_ecs (&ecs
, thr
);
7558 switch_to_thread (thr
);
7564 /* Set a previously stepped thread back to stepping. Returns true on
7565 success, false if the resume is not possible (e.g., the thread
7569 keep_going_stepped_thread (struct thread_info
*tp
)
7571 struct frame_info
*frame
;
7572 struct execution_control_state ecss
;
7573 struct execution_control_state
*ecs
= &ecss
;
7575 /* If the stepping thread exited, then don't try to switch back and
7576 resume it, which could fail in several different ways depending
7577 on the target. Instead, just keep going.
7579 We can find a stepping dead thread in the thread list in two
7582 - The target supports thread exit events, and when the target
7583 tries to delete the thread from the thread list, inferior_ptid
7584 pointed at the exiting thread. In such case, calling
7585 delete_thread does not really remove the thread from the list;
7586 instead, the thread is left listed, with 'exited' state.
7588 - The target's debug interface does not support thread exit
7589 events, and so we have no idea whatsoever if the previously
7590 stepping thread is still alive. For that reason, we need to
7591 synchronously query the target now. */
7593 if (tp
->state
== THREAD_EXITED
|| !target_thread_alive (tp
->ptid
))
7595 infrun_debug_printf ("not resuming previously stepped thread, it has "
7602 infrun_debug_printf ("resuming previously stepped thread");
7604 reset_ecs (ecs
, tp
);
7605 switch_to_thread (tp
);
7607 tp
->suspend
.stop_pc
= regcache_read_pc (get_thread_regcache (tp
));
7608 frame
= get_current_frame ();
7610 /* If the PC of the thread we were trying to single-step has
7611 changed, then that thread has trapped or been signaled, but the
7612 event has not been reported to GDB yet. Re-poll the target
7613 looking for this particular thread's event (i.e. temporarily
7614 enable schedlock) by:
7616 - setting a break at the current PC
7617 - resuming that particular thread, only (by setting trap
7620 This prevents us continuously moving the single-step breakpoint
7621 forward, one instruction at a time, overstepping. */
7623 if (tp
->suspend
.stop_pc
!= tp
->prev_pc
)
7627 infrun_debug_printf ("expected thread advanced also (%s -> %s)",
7628 paddress (target_gdbarch (), tp
->prev_pc
),
7629 paddress (target_gdbarch (), tp
->suspend
.stop_pc
));
7631 /* Clear the info of the previous step-over, as it's no longer
7632 valid (if the thread was trying to step over a breakpoint, it
7633 has already succeeded). It's what keep_going would do too,
7634 if we called it. Do this before trying to insert the sss
7635 breakpoint, otherwise if we were previously trying to step
7636 over this exact address in another thread, the breakpoint is
7638 clear_step_over_info ();
7639 tp
->control
.trap_expected
= 0;
7641 insert_single_step_breakpoint (get_frame_arch (frame
),
7642 get_frame_address_space (frame
),
7643 tp
->suspend
.stop_pc
);
7646 resume_ptid
= internal_resume_ptid (tp
->control
.stepping_command
);
7647 do_target_resume (resume_ptid
, false, GDB_SIGNAL_0
);
7651 infrun_debug_printf ("expected thread still hasn't advanced");
7653 keep_going_pass_signal (ecs
);
7659 /* Is thread TP in the middle of (software or hardware)
7660 single-stepping? (Note the result of this function must never be
7661 passed directly as target_resume's STEP parameter.) */
7664 currently_stepping (struct thread_info
*tp
)
7666 return ((tp
->control
.step_range_end
7667 && tp
->control
.step_resume_breakpoint
== NULL
)
7668 || tp
->control
.trap_expected
7669 || tp
->stepped_breakpoint
7670 || bpstat_should_step ());
7673 /* Inferior has stepped into a subroutine call with source code that
7674 we should not step over. Do step to the first line of code in
7678 handle_step_into_function (struct gdbarch
*gdbarch
,
7679 struct execution_control_state
*ecs
)
7681 fill_in_stop_func (gdbarch
, ecs
);
7683 compunit_symtab
*cust
7684 = find_pc_compunit_symtab (ecs
->event_thread
->suspend
.stop_pc
);
7685 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7686 ecs
->stop_func_start
7687 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7689 symtab_and_line stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7690 /* Use the step_resume_break to step until the end of the prologue,
7691 even if that involves jumps (as it seems to on the vax under
7693 /* If the prologue ends in the middle of a source line, continue to
7694 the end of that source line (if it is still within the function).
7695 Otherwise, just go to end of prologue. */
7696 if (stop_func_sal
.end
7697 && stop_func_sal
.pc
!= ecs
->stop_func_start
7698 && stop_func_sal
.end
< ecs
->stop_func_end
)
7699 ecs
->stop_func_start
= stop_func_sal
.end
;
7701 /* Architectures which require breakpoint adjustment might not be able
7702 to place a breakpoint at the computed address. If so, the test
7703 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7704 ecs->stop_func_start to an address at which a breakpoint may be
7705 legitimately placed.
7707 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7708 made, GDB will enter an infinite loop when stepping through
7709 optimized code consisting of VLIW instructions which contain
7710 subinstructions corresponding to different source lines. On
7711 FR-V, it's not permitted to place a breakpoint on any but the
7712 first subinstruction of a VLIW instruction. When a breakpoint is
7713 set, GDB will adjust the breakpoint address to the beginning of
7714 the VLIW instruction. Thus, we need to make the corresponding
7715 adjustment here when computing the stop address. */
7717 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
7719 ecs
->stop_func_start
7720 = gdbarch_adjust_breakpoint_address (gdbarch
,
7721 ecs
->stop_func_start
);
7724 if (ecs
->stop_func_start
== ecs
->event_thread
->suspend
.stop_pc
)
7726 /* We are already there: stop now. */
7727 end_stepping_range (ecs
);
7732 /* Put the step-breakpoint there and go until there. */
7733 symtab_and_line sr_sal
;
7734 sr_sal
.pc
= ecs
->stop_func_start
;
7735 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
7736 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
7738 /* Do not specify what the fp should be when we stop since on
7739 some machines the prologue is where the new fp value is
7741 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
7743 /* And make sure stepping stops right away then. */
7744 ecs
->event_thread
->control
.step_range_end
7745 = ecs
->event_thread
->control
.step_range_start
;
7750 /* Inferior has stepped backward into a subroutine call with source
7751 code that we should not step over. Do step to the beginning of the
7752 last line of code in it. */
7755 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
7756 struct execution_control_state
*ecs
)
7758 struct compunit_symtab
*cust
;
7759 struct symtab_and_line stop_func_sal
;
7761 fill_in_stop_func (gdbarch
, ecs
);
7763 cust
= find_pc_compunit_symtab (ecs
->event_thread
->suspend
.stop_pc
);
7764 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7765 ecs
->stop_func_start
7766 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7768 stop_func_sal
= find_pc_line (ecs
->event_thread
->suspend
.stop_pc
, 0);
7770 /* OK, we're just going to keep stepping here. */
7771 if (stop_func_sal
.pc
== ecs
->event_thread
->suspend
.stop_pc
)
7773 /* We're there already. Just stop stepping now. */
7774 end_stepping_range (ecs
);
7778 /* Else just reset the step range and keep going.
7779 No step-resume breakpoint, they don't work for
7780 epilogues, which can have multiple entry paths. */
7781 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
7782 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
7788 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7789 This is used to both functions and to skip over code. */
7792 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
7793 struct symtab_and_line sr_sal
,
7794 struct frame_id sr_id
,
7795 enum bptype sr_type
)
7797 /* There should never be more than one step-resume or longjmp-resume
7798 breakpoint per thread, so we should never be setting a new
7799 step_resume_breakpoint when one is already active. */
7800 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
7801 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
7803 infrun_debug_printf ("inserting step-resume breakpoint at %s",
7804 paddress (gdbarch
, sr_sal
.pc
));
7806 inferior_thread ()->control
.step_resume_breakpoint
7807 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
).release ();
7811 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
7812 struct symtab_and_line sr_sal
,
7813 struct frame_id sr_id
)
7815 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
7820 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7821 This is used to skip a potential signal handler.
7823 This is called with the interrupted function's frame. The signal
7824 handler, when it returns, will resume the interrupted function at
7828 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
7830 gdb_assert (return_frame
!= NULL
);
7832 struct gdbarch
*gdbarch
= get_frame_arch (return_frame
);
7834 symtab_and_line sr_sal
;
7835 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
7836 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7837 sr_sal
.pspace
= get_frame_program_space (return_frame
);
7839 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
7840 get_stack_frame_id (return_frame
),
7844 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7845 is used to skip a function after stepping into it (for "next" or if
7846 the called function has no debugging information).
7848 The current function has almost always been reached by single
7849 stepping a call or return instruction. NEXT_FRAME belongs to the
7850 current function, and the breakpoint will be set at the caller's
7853 This is a separate function rather than reusing
7854 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7855 get_prev_frame, which may stop prematurely (see the implementation
7856 of frame_unwind_caller_id for an example). */
7859 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
7861 /* We shouldn't have gotten here if we don't know where the call site
7863 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
7865 struct gdbarch
*gdbarch
= frame_unwind_caller_arch (next_frame
);
7867 symtab_and_line sr_sal
;
7868 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
7869 frame_unwind_caller_pc (next_frame
));
7870 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7871 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
7873 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
7874 frame_unwind_caller_id (next_frame
));
7877 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7878 new breakpoint at the target of a jmp_buf. The handling of
7879 longjmp-resume uses the same mechanisms used for handling
7880 "step-resume" breakpoints. */
7883 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
7885 /* There should never be more than one longjmp-resume breakpoint per
7886 thread, so we should never be setting a new
7887 longjmp_resume_breakpoint when one is already active. */
7888 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
7890 infrun_debug_printf ("inserting longjmp-resume breakpoint at %s",
7891 paddress (gdbarch
, pc
));
7893 inferior_thread ()->control
.exception_resume_breakpoint
=
7894 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
).release ();
7897 /* Insert an exception resume breakpoint. TP is the thread throwing
7898 the exception. The block B is the block of the unwinder debug hook
7899 function. FRAME is the frame corresponding to the call to this
7900 function. SYM is the symbol of the function argument holding the
7901 target PC of the exception. */
7904 insert_exception_resume_breakpoint (struct thread_info
*tp
,
7905 const struct block
*b
,
7906 struct frame_info
*frame
,
7911 struct block_symbol vsym
;
7912 struct value
*value
;
7914 struct breakpoint
*bp
;
7916 vsym
= lookup_symbol_search_name (sym
->search_name (),
7918 value
= read_var_value (vsym
.symbol
, vsym
.block
, frame
);
7919 /* If the value was optimized out, revert to the old behavior. */
7920 if (! value_optimized_out (value
))
7922 handler
= value_as_address (value
);
7924 infrun_debug_printf ("exception resume at %lx",
7925 (unsigned long) handler
);
7927 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7929 bp_exception_resume
).release ();
7931 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7934 bp
->thread
= tp
->global_num
;
7935 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7938 catch (const gdb_exception_error
&e
)
7940 /* We want to ignore errors here. */
7944 /* A helper for check_exception_resume that sets an
7945 exception-breakpoint based on a SystemTap probe. */
7948 insert_exception_resume_from_probe (struct thread_info
*tp
,
7949 const struct bound_probe
*probe
,
7950 struct frame_info
*frame
)
7952 struct value
*arg_value
;
7954 struct breakpoint
*bp
;
7956 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
7960 handler
= value_as_address (arg_value
);
7962 infrun_debug_printf ("exception resume at %s",
7963 paddress (probe
->objfile
->arch (), handler
));
7965 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7966 handler
, bp_exception_resume
).release ();
7967 bp
->thread
= tp
->global_num
;
7968 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7971 /* This is called when an exception has been intercepted. Check to
7972 see whether the exception's destination is of interest, and if so,
7973 set an exception resume breakpoint there. */
7976 check_exception_resume (struct execution_control_state
*ecs
,
7977 struct frame_info
*frame
)
7979 struct bound_probe probe
;
7980 struct symbol
*func
;
7982 /* First see if this exception unwinding breakpoint was set via a
7983 SystemTap probe point. If so, the probe has two arguments: the
7984 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7985 set a breakpoint there. */
7986 probe
= find_probe_by_pc (get_frame_pc (frame
));
7989 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
7993 func
= get_frame_function (frame
);
7999 const struct block
*b
;
8000 struct block_iterator iter
;
8004 /* The exception breakpoint is a thread-specific breakpoint on
8005 the unwinder's debug hook, declared as:
8007 void _Unwind_DebugHook (void *cfa, void *handler);
8009 The CFA argument indicates the frame to which control is
8010 about to be transferred. HANDLER is the destination PC.
8012 We ignore the CFA and set a temporary breakpoint at HANDLER.
8013 This is not extremely efficient but it avoids issues in gdb
8014 with computing the DWARF CFA, and it also works even in weird
8015 cases such as throwing an exception from inside a signal
8018 b
= SYMBOL_BLOCK_VALUE (func
);
8019 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
8021 if (!SYMBOL_IS_ARGUMENT (sym
))
8028 insert_exception_resume_breakpoint (ecs
->event_thread
,
8034 catch (const gdb_exception_error
&e
)
8040 stop_waiting (struct execution_control_state
*ecs
)
8042 infrun_debug_printf ("stop_waiting");
8044 /* Let callers know we don't want to wait for the inferior anymore. */
8045 ecs
->wait_some_more
= 0;
8047 /* If all-stop, but there exists a non-stop target, stop all
8048 threads now that we're presenting the stop to the user. */
8049 if (!non_stop
&& exists_non_stop_target ())
8050 stop_all_threads ("presenting stop to user in all-stop");
8053 /* Like keep_going, but passes the signal to the inferior, even if the
8054 signal is set to nopass. */
8057 keep_going_pass_signal (struct execution_control_state
*ecs
)
8059 gdb_assert (ecs
->event_thread
->ptid
== inferior_ptid
);
8060 gdb_assert (!ecs
->event_thread
->resumed
);
8062 /* Save the pc before execution, to compare with pc after stop. */
8063 ecs
->event_thread
->prev_pc
8064 = regcache_read_pc_protected (get_thread_regcache (ecs
->event_thread
));
8066 if (ecs
->event_thread
->control
.trap_expected
)
8068 struct thread_info
*tp
= ecs
->event_thread
;
8070 infrun_debug_printf ("%s has trap_expected set, "
8071 "resuming to collect trap",
8072 target_pid_to_str (tp
->ptid
).c_str ());
8074 /* We haven't yet gotten our trap, and either: intercepted a
8075 non-signal event (e.g., a fork); or took a signal which we
8076 are supposed to pass through to the inferior. Simply
8078 resume (ecs
->event_thread
->suspend
.stop_signal
);
8080 else if (step_over_info_valid_p ())
8082 /* Another thread is stepping over a breakpoint in-line. If
8083 this thread needs a step-over too, queue the request. In
8084 either case, this resume must be deferred for later. */
8085 struct thread_info
*tp
= ecs
->event_thread
;
8087 if (ecs
->hit_singlestep_breakpoint
8088 || thread_still_needs_step_over (tp
))
8090 infrun_debug_printf ("step-over already in progress: "
8091 "step-over for %s deferred",
8092 target_pid_to_str (tp
->ptid
).c_str ());
8093 global_thread_step_over_chain_enqueue (tp
);
8097 infrun_debug_printf ("step-over in progress: resume of %s deferred",
8098 target_pid_to_str (tp
->ptid
).c_str ());
8103 struct regcache
*regcache
= get_current_regcache ();
8106 step_over_what step_what
;
8108 /* Either the trap was not expected, but we are continuing
8109 anyway (if we got a signal, the user asked it be passed to
8112 We got our expected trap, but decided we should resume from
8115 We're going to run this baby now!
8117 Note that insert_breakpoints won't try to re-insert
8118 already inserted breakpoints. Therefore, we don't
8119 care if breakpoints were already inserted, or not. */
8121 /* If we need to step over a breakpoint, and we're not using
8122 displaced stepping to do so, insert all breakpoints
8123 (watchpoints, etc.) but the one we're stepping over, step one
8124 instruction, and then re-insert the breakpoint when that step
8127 step_what
= thread_still_needs_step_over (ecs
->event_thread
);
8129 remove_bp
= (ecs
->hit_singlestep_breakpoint
8130 || (step_what
& STEP_OVER_BREAKPOINT
));
8131 remove_wps
= (step_what
& STEP_OVER_WATCHPOINT
);
8133 /* We can't use displaced stepping if we need to step past a
8134 watchpoint. The instruction copied to the scratch pad would
8135 still trigger the watchpoint. */
8137 && (remove_wps
|| !use_displaced_stepping (ecs
->event_thread
)))
8139 set_step_over_info (regcache
->aspace (),
8140 regcache_read_pc (regcache
), remove_wps
,
8141 ecs
->event_thread
->global_num
);
8143 else if (remove_wps
)
8144 set_step_over_info (NULL
, 0, remove_wps
, -1);
8146 /* If we now need to do an in-line step-over, we need to stop
8147 all other threads. Note this must be done before
8148 insert_breakpoints below, because that removes the breakpoint
8149 we're about to step over, otherwise other threads could miss
8151 if (step_over_info_valid_p () && target_is_non_stop_p ())
8152 stop_all_threads ("starting in-line step-over");
8154 /* Stop stepping if inserting breakpoints fails. */
8157 insert_breakpoints ();
8159 catch (const gdb_exception_error
&e
)
8161 exception_print (gdb_stderr
, e
);
8163 clear_step_over_info ();
8167 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
8169 resume (ecs
->event_thread
->suspend
.stop_signal
);
8172 prepare_to_wait (ecs
);
8175 /* Called when we should continue running the inferior, because the
8176 current event doesn't cause a user visible stop. This does the
8177 resuming part; waiting for the next event is done elsewhere. */
8180 keep_going (struct execution_control_state
*ecs
)
8182 if (ecs
->event_thread
->control
.trap_expected
8183 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
8184 ecs
->event_thread
->control
.trap_expected
= 0;
8186 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
8187 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
8188 keep_going_pass_signal (ecs
);
8191 /* This function normally comes after a resume, before
8192 handle_inferior_event exits. It takes care of any last bits of
8193 housekeeping, and sets the all-important wait_some_more flag. */
8196 prepare_to_wait (struct execution_control_state
*ecs
)
8198 infrun_debug_printf ("prepare_to_wait");
8200 ecs
->wait_some_more
= 1;
8202 /* If the target can't async, emulate it by marking the infrun event
8203 handler such that as soon as we get back to the event-loop, we
8204 immediately end up in fetch_inferior_event again calling
8206 if (!target_can_async_p ())
8207 mark_infrun_async_event_handler ();
8210 /* We are done with the step range of a step/next/si/ni command.
8211 Called once for each n of a "step n" operation. */
8214 end_stepping_range (struct execution_control_state
*ecs
)
8216 ecs
->event_thread
->control
.stop_step
= 1;
8220 /* Several print_*_reason functions to print why the inferior has stopped.
8221 We always print something when the inferior exits, or receives a signal.
8222 The rest of the cases are dealt with later on in normal_stop and
8223 print_it_typical. Ideally there should be a call to one of these
8224 print_*_reason functions functions from handle_inferior_event each time
8225 stop_waiting is called.
8227 Note that we don't call these directly, instead we delegate that to
8228 the interpreters, through observers. Interpreters then call these
8229 with whatever uiout is right. */
8232 print_end_stepping_range_reason (struct ui_out
*uiout
)
8234 /* For CLI-like interpreters, print nothing. */
8236 if (uiout
->is_mi_like_p ())
8238 uiout
->field_string ("reason",
8239 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
8244 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
8246 annotate_signalled ();
8247 if (uiout
->is_mi_like_p ())
8249 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
8250 uiout
->text ("\nProgram terminated with signal ");
8251 annotate_signal_name ();
8252 uiout
->field_string ("signal-name",
8253 gdb_signal_to_name (siggnal
));
8254 annotate_signal_name_end ();
8256 annotate_signal_string ();
8257 uiout
->field_string ("signal-meaning",
8258 gdb_signal_to_string (siggnal
));
8259 annotate_signal_string_end ();
8260 uiout
->text (".\n");
8261 uiout
->text ("The program no longer exists.\n");
8265 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
8267 struct inferior
*inf
= current_inferior ();
8268 std::string pidstr
= target_pid_to_str (ptid_t (inf
->pid
));
8270 annotate_exited (exitstatus
);
8273 if (uiout
->is_mi_like_p ())
8274 uiout
->field_string ("reason", async_reason_lookup (EXEC_ASYNC_EXITED
));
8275 std::string exit_code_str
8276 = string_printf ("0%o", (unsigned int) exitstatus
);
8277 uiout
->message ("[Inferior %s (%s) exited with code %pF]\n",
8278 plongest (inf
->num
), pidstr
.c_str (),
8279 string_field ("exit-code", exit_code_str
.c_str ()));
8283 if (uiout
->is_mi_like_p ())
8285 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
8286 uiout
->message ("[Inferior %s (%s) exited normally]\n",
8287 plongest (inf
->num
), pidstr
.c_str ());
8292 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
8294 struct thread_info
*thr
= inferior_thread ();
8298 if (uiout
->is_mi_like_p ())
8300 else if (show_thread_that_caused_stop ())
8304 uiout
->text ("\nThread ");
8305 uiout
->field_string ("thread-id", print_thread_id (thr
));
8307 name
= thr
->name
!= NULL
? thr
->name
: target_thread_name (thr
);
8310 uiout
->text (" \"");
8311 uiout
->field_string ("name", name
);
8316 uiout
->text ("\nProgram");
8318 if (siggnal
== GDB_SIGNAL_0
&& !uiout
->is_mi_like_p ())
8319 uiout
->text (" stopped");
8322 uiout
->text (" received signal ");
8323 annotate_signal_name ();
8324 if (uiout
->is_mi_like_p ())
8326 ("reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
8327 uiout
->field_string ("signal-name", gdb_signal_to_name (siggnal
));
8328 annotate_signal_name_end ();
8330 annotate_signal_string ();
8331 uiout
->field_string ("signal-meaning", gdb_signal_to_string (siggnal
));
8333 struct regcache
*regcache
= get_current_regcache ();
8334 struct gdbarch
*gdbarch
= regcache
->arch ();
8335 if (gdbarch_report_signal_info_p (gdbarch
))
8336 gdbarch_report_signal_info (gdbarch
, uiout
, siggnal
);
8338 annotate_signal_string_end ();
8340 uiout
->text (".\n");
8344 print_no_history_reason (struct ui_out
*uiout
)
8346 uiout
->text ("\nNo more reverse-execution history.\n");
8349 /* Print current location without a level number, if we have changed
8350 functions or hit a breakpoint. Print source line if we have one.
8351 bpstat_print contains the logic deciding in detail what to print,
8352 based on the event(s) that just occurred. */
8355 print_stop_location (struct target_waitstatus
*ws
)
8358 enum print_what source_flag
;
8359 int do_frame_printing
= 1;
8360 struct thread_info
*tp
= inferior_thread ();
8362 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
8366 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
8367 should) carry around the function and does (or should) use
8368 that when doing a frame comparison. */
8369 if (tp
->control
.stop_step
8370 && frame_id_eq (tp
->control
.step_frame_id
,
8371 get_frame_id (get_current_frame ()))
8372 && (tp
->control
.step_start_function
8373 == find_pc_function (tp
->suspend
.stop_pc
)))
8375 /* Finished step, just print source line. */
8376 source_flag
= SRC_LINE
;
8380 /* Print location and source line. */
8381 source_flag
= SRC_AND_LOC
;
8384 case PRINT_SRC_AND_LOC
:
8385 /* Print location and source line. */
8386 source_flag
= SRC_AND_LOC
;
8388 case PRINT_SRC_ONLY
:
8389 source_flag
= SRC_LINE
;
8392 /* Something bogus. */
8393 source_flag
= SRC_LINE
;
8394 do_frame_printing
= 0;
8397 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
8400 /* The behavior of this routine with respect to the source
8402 SRC_LINE: Print only source line
8403 LOCATION: Print only location
8404 SRC_AND_LOC: Print location and source line. */
8405 if (do_frame_printing
)
8406 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
8412 print_stop_event (struct ui_out
*uiout
, bool displays
)
8414 struct target_waitstatus last
;
8415 struct thread_info
*tp
;
8417 get_last_target_status (nullptr, nullptr, &last
);
8420 scoped_restore save_uiout
= make_scoped_restore (¤t_uiout
, uiout
);
8422 print_stop_location (&last
);
8424 /* Display the auto-display expressions. */
8429 tp
= inferior_thread ();
8430 if (tp
->thread_fsm
!= NULL
8431 && tp
->thread_fsm
->finished_p ())
8433 struct return_value_info
*rv
;
8435 rv
= tp
->thread_fsm
->return_value ();
8437 print_return_value (uiout
, rv
);
8444 maybe_remove_breakpoints (void)
8446 if (!breakpoints_should_be_inserted_now () && target_has_execution ())
8448 if (remove_breakpoints ())
8450 target_terminal::ours_for_output ();
8451 printf_filtered (_("Cannot remove breakpoints because "
8452 "program is no longer writable.\nFurther "
8453 "execution is probably impossible.\n"));
8458 /* The execution context that just caused a normal stop. */
8464 DISABLE_COPY_AND_ASSIGN (stop_context
);
8466 bool changed () const;
8471 /* The event PTID. */
8475 /* If stopp for a thread event, this is the thread that caused the
8477 thread_info_ref thread
;
8479 /* The inferior that caused the stop. */
8483 /* Initializes a new stop context. If stopped for a thread event, this
8484 takes a strong reference to the thread. */
8486 stop_context::stop_context ()
8488 stop_id
= get_stop_id ();
8489 ptid
= inferior_ptid
;
8490 inf_num
= current_inferior ()->num
;
8492 if (inferior_ptid
!= null_ptid
)
8494 /* Take a strong reference so that the thread can't be deleted
8496 thread
= thread_info_ref::new_reference (inferior_thread ());
8500 /* Return true if the current context no longer matches the saved stop
8504 stop_context::changed () const
8506 if (ptid
!= inferior_ptid
)
8508 if (inf_num
!= current_inferior ()->num
)
8510 if (thread
!= NULL
&& thread
->state
!= THREAD_STOPPED
)
8512 if (get_stop_id () != stop_id
)
8522 struct target_waitstatus last
;
8524 get_last_target_status (nullptr, nullptr, &last
);
8528 /* If an exception is thrown from this point on, make sure to
8529 propagate GDB's knowledge of the executing state to the
8530 frontend/user running state. A QUIT is an easy exception to see
8531 here, so do this before any filtered output. */
8533 ptid_t finish_ptid
= null_ptid
;
8536 finish_ptid
= minus_one_ptid
;
8537 else if (last
.kind
== TARGET_WAITKIND_SIGNALLED
8538 || last
.kind
== TARGET_WAITKIND_EXITED
)
8540 /* On some targets, we may still have live threads in the
8541 inferior when we get a process exit event. E.g., for
8542 "checkpoint", when the current checkpoint/fork exits,
8543 linux-fork.c automatically switches to another fork from
8544 within target_mourn_inferior. */
8545 if (inferior_ptid
!= null_ptid
)
8546 finish_ptid
= ptid_t (inferior_ptid
.pid ());
8548 else if (last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8549 finish_ptid
= inferior_ptid
;
8551 gdb::optional
<scoped_finish_thread_state
> maybe_finish_thread_state
;
8552 if (finish_ptid
!= null_ptid
)
8554 maybe_finish_thread_state
.emplace
8555 (user_visible_resume_target (finish_ptid
), finish_ptid
);
8558 /* As we're presenting a stop, and potentially removing breakpoints,
8559 update the thread list so we can tell whether there are threads
8560 running on the target. With target remote, for example, we can
8561 only learn about new threads when we explicitly update the thread
8562 list. Do this before notifying the interpreters about signal
8563 stops, end of stepping ranges, etc., so that the "new thread"
8564 output is emitted before e.g., "Program received signal FOO",
8565 instead of after. */
8566 update_thread_list ();
8568 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
8569 gdb::observers::signal_received
.notify (inferior_thread ()->suspend
.stop_signal
);
8571 /* As with the notification of thread events, we want to delay
8572 notifying the user that we've switched thread context until
8573 the inferior actually stops.
8575 There's no point in saying anything if the inferior has exited.
8576 Note that SIGNALLED here means "exited with a signal", not
8577 "received a signal".
8579 Also skip saying anything in non-stop mode. In that mode, as we
8580 don't want GDB to switch threads behind the user's back, to avoid
8581 races where the user is typing a command to apply to thread x,
8582 but GDB switches to thread y before the user finishes entering
8583 the command, fetch_inferior_event installs a cleanup to restore
8584 the current thread back to the thread the user had selected right
8585 after this event is handled, so we're not really switching, only
8586 informing of a stop. */
8588 && previous_inferior_ptid
!= inferior_ptid
8589 && target_has_execution ()
8590 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
8591 && last
.kind
!= TARGET_WAITKIND_EXITED
8592 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8594 SWITCH_THRU_ALL_UIS ()
8596 target_terminal::ours_for_output ();
8597 printf_filtered (_("[Switching to %s]\n"),
8598 target_pid_to_str (inferior_ptid
).c_str ());
8599 annotate_thread_changed ();
8601 previous_inferior_ptid
= inferior_ptid
;
8604 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
8606 SWITCH_THRU_ALL_UIS ()
8607 if (current_ui
->prompt_state
== PROMPT_BLOCKED
)
8609 target_terminal::ours_for_output ();
8610 printf_filtered (_("No unwaited-for children left.\n"));
8614 /* Note: this depends on the update_thread_list call above. */
8615 maybe_remove_breakpoints ();
8617 /* If an auto-display called a function and that got a signal,
8618 delete that auto-display to avoid an infinite recursion. */
8620 if (stopped_by_random_signal
)
8621 disable_current_display ();
8623 SWITCH_THRU_ALL_UIS ()
8625 async_enable_stdin ();
8628 /* Let the user/frontend see the threads as stopped. */
8629 maybe_finish_thread_state
.reset ();
8631 /* Select innermost stack frame - i.e., current frame is frame 0,
8632 and current location is based on that. Handle the case where the
8633 dummy call is returning after being stopped. E.g. the dummy call
8634 previously hit a breakpoint. (If the dummy call returns
8635 normally, we won't reach here.) Do this before the stop hook is
8636 run, so that it doesn't get to see the temporary dummy frame,
8637 which is not where we'll present the stop. */
8638 if (has_stack_frames ())
8640 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
8642 /* Pop the empty frame that contains the stack dummy. This
8643 also restores inferior state prior to the call (struct
8644 infcall_suspend_state). */
8645 struct frame_info
*frame
= get_current_frame ();
8647 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
8649 /* frame_pop calls reinit_frame_cache as the last thing it
8650 does which means there's now no selected frame. */
8653 select_frame (get_current_frame ());
8655 /* Set the current source location. */
8656 set_current_sal_from_frame (get_current_frame ());
8659 /* Look up the hook_stop and run it (CLI internally handles problem
8660 of stop_command's pre-hook not existing). */
8661 if (stop_command
!= NULL
)
8663 stop_context saved_context
;
8667 execute_cmd_pre_hook (stop_command
);
8669 catch (const gdb_exception
&ex
)
8671 exception_fprintf (gdb_stderr
, ex
,
8672 "Error while running hook_stop:\n");
8675 /* If the stop hook resumes the target, then there's no point in
8676 trying to notify about the previous stop; its context is
8677 gone. Likewise if the command switches thread or inferior --
8678 the observers would print a stop for the wrong
8680 if (saved_context
.changed ())
8684 /* Notify observers about the stop. This is where the interpreters
8685 print the stop event. */
8686 if (inferior_ptid
!= null_ptid
)
8687 gdb::observers::normal_stop
.notify (inferior_thread ()->control
.stop_bpstat
,
8690 gdb::observers::normal_stop
.notify (NULL
, stop_print_frame
);
8692 annotate_stopped ();
8694 if (target_has_execution ())
8696 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
8697 && last
.kind
!= TARGET_WAITKIND_EXITED
8698 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8699 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8700 Delete any breakpoint that is to be deleted at the next stop. */
8701 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
8704 /* Try to get rid of automatically added inferiors that are no
8705 longer needed. Keeping those around slows down things linearly.
8706 Note that this never removes the current inferior. */
8713 signal_stop_state (int signo
)
8715 return signal_stop
[signo
];
8719 signal_print_state (int signo
)
8721 return signal_print
[signo
];
8725 signal_pass_state (int signo
)
8727 return signal_program
[signo
];
8731 signal_cache_update (int signo
)
8735 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
8736 signal_cache_update (signo
);
8741 signal_pass
[signo
] = (signal_stop
[signo
] == 0
8742 && signal_print
[signo
] == 0
8743 && signal_program
[signo
] == 1
8744 && signal_catch
[signo
] == 0);
8748 signal_stop_update (int signo
, int state
)
8750 int ret
= signal_stop
[signo
];
8752 signal_stop
[signo
] = state
;
8753 signal_cache_update (signo
);
8758 signal_print_update (int signo
, int state
)
8760 int ret
= signal_print
[signo
];
8762 signal_print
[signo
] = state
;
8763 signal_cache_update (signo
);
8768 signal_pass_update (int signo
, int state
)
8770 int ret
= signal_program
[signo
];
8772 signal_program
[signo
] = state
;
8773 signal_cache_update (signo
);
8777 /* Update the global 'signal_catch' from INFO and notify the
8781 signal_catch_update (const unsigned int *info
)
8785 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
8786 signal_catch
[i
] = info
[i
] > 0;
8787 signal_cache_update (-1);
8788 target_pass_signals (signal_pass
);
8792 sig_print_header (void)
8794 printf_filtered (_("Signal Stop\tPrint\tPass "
8795 "to program\tDescription\n"));
8799 sig_print_info (enum gdb_signal oursig
)
8801 const char *name
= gdb_signal_to_name (oursig
);
8802 int name_padding
= 13 - strlen (name
);
8804 if (name_padding
<= 0)
8807 printf_filtered ("%s", name
);
8808 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
8809 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
8810 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
8811 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
8812 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
8815 /* Specify how various signals in the inferior should be handled. */
8818 handle_command (const char *args
, int from_tty
)
8820 int digits
, wordlen
;
8821 int sigfirst
, siglast
;
8822 enum gdb_signal oursig
;
8827 error_no_arg (_("signal to handle"));
8830 /* Allocate and zero an array of flags for which signals to handle. */
8832 const size_t nsigs
= GDB_SIGNAL_LAST
;
8833 unsigned char sigs
[nsigs
] {};
8835 /* Break the command line up into args. */
8837 gdb_argv
built_argv (args
);
8839 /* Walk through the args, looking for signal oursigs, signal names, and
8840 actions. Signal numbers and signal names may be interspersed with
8841 actions, with the actions being performed for all signals cumulatively
8842 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8844 for (char *arg
: built_argv
)
8846 wordlen
= strlen (arg
);
8847 for (digits
= 0; isdigit (arg
[digits
]); digits
++)
8851 sigfirst
= siglast
= -1;
8853 if (wordlen
>= 1 && !strncmp (arg
, "all", wordlen
))
8855 /* Apply action to all signals except those used by the
8856 debugger. Silently skip those. */
8859 siglast
= nsigs
- 1;
8861 else if (wordlen
>= 1 && !strncmp (arg
, "stop", wordlen
))
8863 SET_SIGS (nsigs
, sigs
, signal_stop
);
8864 SET_SIGS (nsigs
, sigs
, signal_print
);
8866 else if (wordlen
>= 1 && !strncmp (arg
, "ignore", wordlen
))
8868 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8870 else if (wordlen
>= 2 && !strncmp (arg
, "print", wordlen
))
8872 SET_SIGS (nsigs
, sigs
, signal_print
);
8874 else if (wordlen
>= 2 && !strncmp (arg
, "pass", wordlen
))
8876 SET_SIGS (nsigs
, sigs
, signal_program
);
8878 else if (wordlen
>= 3 && !strncmp (arg
, "nostop", wordlen
))
8880 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8882 else if (wordlen
>= 3 && !strncmp (arg
, "noignore", wordlen
))
8884 SET_SIGS (nsigs
, sigs
, signal_program
);
8886 else if (wordlen
>= 4 && !strncmp (arg
, "noprint", wordlen
))
8888 UNSET_SIGS (nsigs
, sigs
, signal_print
);
8889 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8891 else if (wordlen
>= 4 && !strncmp (arg
, "nopass", wordlen
))
8893 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8895 else if (digits
> 0)
8897 /* It is numeric. The numeric signal refers to our own
8898 internal signal numbering from target.h, not to host/target
8899 signal number. This is a feature; users really should be
8900 using symbolic names anyway, and the common ones like
8901 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8903 sigfirst
= siglast
= (int)
8904 gdb_signal_from_command (atoi (arg
));
8905 if (arg
[digits
] == '-')
8908 gdb_signal_from_command (atoi (arg
+ digits
+ 1));
8910 if (sigfirst
> siglast
)
8912 /* Bet he didn't figure we'd think of this case... */
8913 std::swap (sigfirst
, siglast
);
8918 oursig
= gdb_signal_from_name (arg
);
8919 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
8921 sigfirst
= siglast
= (int) oursig
;
8925 /* Not a number and not a recognized flag word => complain. */
8926 error (_("Unrecognized or ambiguous flag word: \"%s\"."), arg
);
8930 /* If any signal numbers or symbol names were found, set flags for
8931 which signals to apply actions to. */
8933 for (int signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
8935 switch ((enum gdb_signal
) signum
)
8937 case GDB_SIGNAL_TRAP
:
8938 case GDB_SIGNAL_INT
:
8939 if (!allsigs
&& !sigs
[signum
])
8941 if (query (_("%s is used by the debugger.\n\
8942 Are you sure you want to change it? "),
8943 gdb_signal_to_name ((enum gdb_signal
) signum
)))
8948 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8952 case GDB_SIGNAL_DEFAULT
:
8953 case GDB_SIGNAL_UNKNOWN
:
8954 /* Make sure that "all" doesn't print these. */
8963 for (int signum
= 0; signum
< nsigs
; signum
++)
8966 signal_cache_update (-1);
8967 target_pass_signals (signal_pass
);
8968 target_program_signals (signal_program
);
8972 /* Show the results. */
8973 sig_print_header ();
8974 for (; signum
< nsigs
; signum
++)
8976 sig_print_info ((enum gdb_signal
) signum
);
8983 /* Complete the "handle" command. */
8986 handle_completer (struct cmd_list_element
*ignore
,
8987 completion_tracker
&tracker
,
8988 const char *text
, const char *word
)
8990 static const char * const keywords
[] =
9004 signal_completer (ignore
, tracker
, text
, word
);
9005 complete_on_enum (tracker
, keywords
, word
, word
);
9009 gdb_signal_from_command (int num
)
9011 if (num
>= 1 && num
<= 15)
9012 return (enum gdb_signal
) num
;
9013 error (_("Only signals 1-15 are valid as numeric signals.\n\
9014 Use \"info signals\" for a list of symbolic signals."));
9017 /* Print current contents of the tables set by the handle command.
9018 It is possible we should just be printing signals actually used
9019 by the current target (but for things to work right when switching
9020 targets, all signals should be in the signal tables). */
9023 info_signals_command (const char *signum_exp
, int from_tty
)
9025 enum gdb_signal oursig
;
9027 sig_print_header ();
9031 /* First see if this is a symbol name. */
9032 oursig
= gdb_signal_from_name (signum_exp
);
9033 if (oursig
== GDB_SIGNAL_UNKNOWN
)
9035 /* No, try numeric. */
9037 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
9039 sig_print_info (oursig
);
9043 printf_filtered ("\n");
9044 /* These ugly casts brought to you by the native VAX compiler. */
9045 for (oursig
= GDB_SIGNAL_FIRST
;
9046 (int) oursig
< (int) GDB_SIGNAL_LAST
;
9047 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
9051 if (oursig
!= GDB_SIGNAL_UNKNOWN
9052 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
9053 sig_print_info (oursig
);
9056 printf_filtered (_("\nUse the \"handle\" command "
9057 "to change these tables.\n"));
9060 /* The $_siginfo convenience variable is a bit special. We don't know
9061 for sure the type of the value until we actually have a chance to
9062 fetch the data. The type can change depending on gdbarch, so it is
9063 also dependent on which thread you have selected.
9065 1. making $_siginfo be an internalvar that creates a new value on
9068 2. making the value of $_siginfo be an lval_computed value. */
9070 /* This function implements the lval_computed support for reading a
9074 siginfo_value_read (struct value
*v
)
9076 LONGEST transferred
;
9078 /* If we can access registers, so can we access $_siginfo. Likewise
9080 validate_registers_access ();
9083 target_read (current_inferior ()->top_target (),
9084 TARGET_OBJECT_SIGNAL_INFO
,
9086 value_contents_all_raw (v
),
9088 TYPE_LENGTH (value_type (v
)));
9090 if (transferred
!= TYPE_LENGTH (value_type (v
)))
9091 error (_("Unable to read siginfo"));
9094 /* This function implements the lval_computed support for writing a
9098 siginfo_value_write (struct value
*v
, struct value
*fromval
)
9100 LONGEST transferred
;
9102 /* If we can access registers, so can we access $_siginfo. Likewise
9104 validate_registers_access ();
9106 transferred
= target_write (current_inferior ()->top_target (),
9107 TARGET_OBJECT_SIGNAL_INFO
,
9109 value_contents_all_raw (fromval
),
9111 TYPE_LENGTH (value_type (fromval
)));
9113 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
9114 error (_("Unable to write siginfo"));
9117 static const struct lval_funcs siginfo_value_funcs
=
9123 /* Return a new value with the correct type for the siginfo object of
9124 the current thread using architecture GDBARCH. Return a void value
9125 if there's no object available. */
9127 static struct value
*
9128 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
9131 if (target_has_stack ()
9132 && inferior_ptid
!= null_ptid
9133 && gdbarch_get_siginfo_type_p (gdbarch
))
9135 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
9137 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
9140 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
9144 /* infcall_suspend_state contains state about the program itself like its
9145 registers and any signal it received when it last stopped.
9146 This state must be restored regardless of how the inferior function call
9147 ends (either successfully, or after it hits a breakpoint or signal)
9148 if the program is to properly continue where it left off. */
9150 class infcall_suspend_state
9153 /* Capture state from GDBARCH, TP, and REGCACHE that must be restored
9154 once the inferior function call has finished. */
9155 infcall_suspend_state (struct gdbarch
*gdbarch
,
9156 const struct thread_info
*tp
,
9157 struct regcache
*regcache
)
9158 : m_thread_suspend (tp
->suspend
),
9159 m_registers (new readonly_detached_regcache (*regcache
))
9161 gdb::unique_xmalloc_ptr
<gdb_byte
> siginfo_data
;
9163 if (gdbarch_get_siginfo_type_p (gdbarch
))
9165 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
9166 size_t len
= TYPE_LENGTH (type
);
9168 siginfo_data
.reset ((gdb_byte
*) xmalloc (len
));
9170 if (target_read (current_inferior ()->top_target (),
9171 TARGET_OBJECT_SIGNAL_INFO
, NULL
,
9172 siginfo_data
.get (), 0, len
) != len
)
9174 /* Errors ignored. */
9175 siginfo_data
.reset (nullptr);
9181 m_siginfo_gdbarch
= gdbarch
;
9182 m_siginfo_data
= std::move (siginfo_data
);
9186 /* Return a pointer to the stored register state. */
9188 readonly_detached_regcache
*registers () const
9190 return m_registers
.get ();
9193 /* Restores the stored state into GDBARCH, TP, and REGCACHE. */
9195 void restore (struct gdbarch
*gdbarch
,
9196 struct thread_info
*tp
,
9197 struct regcache
*regcache
) const
9199 tp
->suspend
= m_thread_suspend
;
9201 if (m_siginfo_gdbarch
== gdbarch
)
9203 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
9205 /* Errors ignored. */
9206 target_write (current_inferior ()->top_target (),
9207 TARGET_OBJECT_SIGNAL_INFO
, NULL
,
9208 m_siginfo_data
.get (), 0, TYPE_LENGTH (type
));
9211 /* The inferior can be gone if the user types "print exit(0)"
9212 (and perhaps other times). */
9213 if (target_has_execution ())
9214 /* NB: The register write goes through to the target. */
9215 regcache
->restore (registers ());
9219 /* How the current thread stopped before the inferior function call was
9221 struct thread_suspend_state m_thread_suspend
;
9223 /* The registers before the inferior function call was executed. */
9224 std::unique_ptr
<readonly_detached_regcache
> m_registers
;
9226 /* Format of SIGINFO_DATA or NULL if it is not present. */
9227 struct gdbarch
*m_siginfo_gdbarch
= nullptr;
9229 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
9230 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
9231 content would be invalid. */
9232 gdb::unique_xmalloc_ptr
<gdb_byte
> m_siginfo_data
;
9235 infcall_suspend_state_up
9236 save_infcall_suspend_state ()
9238 struct thread_info
*tp
= inferior_thread ();
9239 struct regcache
*regcache
= get_current_regcache ();
9240 struct gdbarch
*gdbarch
= regcache
->arch ();
9242 infcall_suspend_state_up inf_state
9243 (new struct infcall_suspend_state (gdbarch
, tp
, regcache
));
9245 /* Having saved the current state, adjust the thread state, discarding
9246 any stop signal information. The stop signal is not useful when
9247 starting an inferior function call, and run_inferior_call will not use
9248 the signal due to its `proceed' call with GDB_SIGNAL_0. */
9249 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
9254 /* Restore inferior session state to INF_STATE. */
9257 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
9259 struct thread_info
*tp
= inferior_thread ();
9260 struct regcache
*regcache
= get_current_regcache ();
9261 struct gdbarch
*gdbarch
= regcache
->arch ();
9263 inf_state
->restore (gdbarch
, tp
, regcache
);
9264 discard_infcall_suspend_state (inf_state
);
9268 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
9273 readonly_detached_regcache
*
9274 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
9276 return inf_state
->registers ();
9279 /* infcall_control_state contains state regarding gdb's control of the
9280 inferior itself like stepping control. It also contains session state like
9281 the user's currently selected frame. */
9283 struct infcall_control_state
9285 struct thread_control_state thread_control
;
9286 struct inferior_control_state inferior_control
;
9289 enum stop_stack_kind stop_stack_dummy
= STOP_NONE
;
9290 int stopped_by_random_signal
= 0;
9292 /* ID and level of the selected frame when the inferior function
9294 struct frame_id selected_frame_id
{};
9295 int selected_frame_level
= -1;
9298 /* Save all of the information associated with the inferior<==>gdb
9301 infcall_control_state_up
9302 save_infcall_control_state ()
9304 infcall_control_state_up
inf_status (new struct infcall_control_state
);
9305 struct thread_info
*tp
= inferior_thread ();
9306 struct inferior
*inf
= current_inferior ();
9308 inf_status
->thread_control
= tp
->control
;
9309 inf_status
->inferior_control
= inf
->control
;
9311 tp
->control
.step_resume_breakpoint
= NULL
;
9312 tp
->control
.exception_resume_breakpoint
= NULL
;
9314 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
9315 chain. If caller's caller is walking the chain, they'll be happier if we
9316 hand them back the original chain when restore_infcall_control_state is
9318 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
9321 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
9322 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
9324 save_selected_frame (&inf_status
->selected_frame_id
,
9325 &inf_status
->selected_frame_level
);
9330 /* Restore inferior session state to INF_STATUS. */
9333 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
9335 struct thread_info
*tp
= inferior_thread ();
9336 struct inferior
*inf
= current_inferior ();
9338 if (tp
->control
.step_resume_breakpoint
)
9339 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
9341 if (tp
->control
.exception_resume_breakpoint
)
9342 tp
->control
.exception_resume_breakpoint
->disposition
9343 = disp_del_at_next_stop
;
9345 /* Handle the bpstat_copy of the chain. */
9346 bpstat_clear (&tp
->control
.stop_bpstat
);
9348 tp
->control
= inf_status
->thread_control
;
9349 inf
->control
= inf_status
->inferior_control
;
9352 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
9353 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
9355 if (target_has_stack ())
9357 restore_selected_frame (inf_status
->selected_frame_id
,
9358 inf_status
->selected_frame_level
);
9365 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
9367 if (inf_status
->thread_control
.step_resume_breakpoint
)
9368 inf_status
->thread_control
.step_resume_breakpoint
->disposition
9369 = disp_del_at_next_stop
;
9371 if (inf_status
->thread_control
.exception_resume_breakpoint
)
9372 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
9373 = disp_del_at_next_stop
;
9375 /* See save_infcall_control_state for info on stop_bpstat. */
9376 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
9384 clear_exit_convenience_vars (void)
9386 clear_internalvar (lookup_internalvar ("_exitsignal"));
9387 clear_internalvar (lookup_internalvar ("_exitcode"));
9391 /* User interface for reverse debugging:
9392 Set exec-direction / show exec-direction commands
9393 (returns error unless target implements to_set_exec_direction method). */
9395 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
9396 static const char exec_forward
[] = "forward";
9397 static const char exec_reverse
[] = "reverse";
9398 static const char *exec_direction
= exec_forward
;
9399 static const char *const exec_direction_names
[] = {
9406 set_exec_direction_func (const char *args
, int from_tty
,
9407 struct cmd_list_element
*cmd
)
9409 if (target_can_execute_reverse ())
9411 if (!strcmp (exec_direction
, exec_forward
))
9412 execution_direction
= EXEC_FORWARD
;
9413 else if (!strcmp (exec_direction
, exec_reverse
))
9414 execution_direction
= EXEC_REVERSE
;
9418 exec_direction
= exec_forward
;
9419 error (_("Target does not support this operation."));
9424 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
9425 struct cmd_list_element
*cmd
, const char *value
)
9427 switch (execution_direction
) {
9429 fprintf_filtered (out
, _("Forward.\n"));
9432 fprintf_filtered (out
, _("Reverse.\n"));
9435 internal_error (__FILE__
, __LINE__
,
9436 _("bogus execution_direction value: %d"),
9437 (int) execution_direction
);
9442 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
9443 struct cmd_list_element
*c
, const char *value
)
9445 fprintf_filtered (file
, _("Resuming the execution of threads "
9446 "of all processes is %s.\n"), value
);
9449 /* Implementation of `siginfo' variable. */
9451 static const struct internalvar_funcs siginfo_funcs
=
9458 /* Callback for infrun's target events source. This is marked when a
9459 thread has a pending status to process. */
9462 infrun_async_inferior_event_handler (gdb_client_data data
)
9464 clear_async_event_handler (infrun_async_inferior_event_token
);
9465 inferior_event_handler (INF_REG_EVENT
);
9472 /* Verify that when two threads with the same ptid exist (from two different
9473 targets) and one of them changes ptid, we only update inferior_ptid if
9474 it is appropriate. */
9477 infrun_thread_ptid_changed ()
9479 gdbarch
*arch
= current_inferior ()->gdbarch
;
9481 /* The thread which inferior_ptid represents changes ptid. */
9483 scoped_restore_current_pspace_and_thread restore
;
9485 scoped_mock_context
<test_target_ops
> target1 (arch
);
9486 scoped_mock_context
<test_target_ops
> target2 (arch
);
9487 target2
.mock_inferior
.next
= &target1
.mock_inferior
;
9489 ptid_t
old_ptid (111, 222);
9490 ptid_t
new_ptid (111, 333);
9492 target1
.mock_inferior
.pid
= old_ptid
.pid ();
9493 target1
.mock_thread
.ptid
= old_ptid
;
9494 target2
.mock_inferior
.pid
= old_ptid
.pid ();
9495 target2
.mock_thread
.ptid
= old_ptid
;
9497 auto restore_inferior_ptid
= make_scoped_restore (&inferior_ptid
, old_ptid
);
9498 set_current_inferior (&target1
.mock_inferior
);
9500 thread_change_ptid (&target1
.mock_target
, old_ptid
, new_ptid
);
9502 gdb_assert (inferior_ptid
== new_ptid
);
9505 /* A thread with the same ptid as inferior_ptid, but from another target,
9508 scoped_restore_current_pspace_and_thread restore
;
9510 scoped_mock_context
<test_target_ops
> target1 (arch
);
9511 scoped_mock_context
<test_target_ops
> target2 (arch
);
9512 target2
.mock_inferior
.next
= &target1
.mock_inferior
;
9514 ptid_t
old_ptid (111, 222);
9515 ptid_t
new_ptid (111, 333);
9517 target1
.mock_inferior
.pid
= old_ptid
.pid ();
9518 target1
.mock_thread
.ptid
= old_ptid
;
9519 target2
.mock_inferior
.pid
= old_ptid
.pid ();
9520 target2
.mock_thread
.ptid
= old_ptid
;
9522 auto restore_inferior_ptid
= make_scoped_restore (&inferior_ptid
, old_ptid
);
9523 set_current_inferior (&target2
.mock_inferior
);
9525 thread_change_ptid (&target1
.mock_target
, old_ptid
, new_ptid
);
9527 gdb_assert (inferior_ptid
== old_ptid
);
9531 } /* namespace selftests */
9533 #endif /* GDB_SELF_TEST */
9535 void _initialize_infrun ();
9537 _initialize_infrun ()
9539 struct cmd_list_element
*c
;
9541 /* Register extra event sources in the event loop. */
9542 infrun_async_inferior_event_token
9543 = create_async_event_handler (infrun_async_inferior_event_handler
, NULL
,
9546 cmd_list_element
*info_signals_cmd
9547 = add_info ("signals", info_signals_command
, _("\
9548 What debugger does when program gets various signals.\n\
9549 Specify a signal as argument to print info on that signal only."));
9550 add_info_alias ("handle", info_signals_cmd
, 0);
9552 c
= add_com ("handle", class_run
, handle_command
, _("\
9553 Specify how to handle signals.\n\
9554 Usage: handle SIGNAL [ACTIONS]\n\
9555 Args are signals and actions to apply to those signals.\n\
9556 If no actions are specified, the current settings for the specified signals\n\
9557 will be displayed instead.\n\
9559 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
9560 from 1-15 are allowed for compatibility with old versions of GDB.\n\
9561 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
9562 The special arg \"all\" is recognized to mean all signals except those\n\
9563 used by the debugger, typically SIGTRAP and SIGINT.\n\
9565 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
9566 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
9567 Stop means reenter debugger if this signal happens (implies print).\n\
9568 Print means print a message if this signal happens.\n\
9569 Pass means let program see this signal; otherwise program doesn't know.\n\
9570 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
9571 Pass and Stop may be combined.\n\
9573 Multiple signals may be specified. Signal numbers and signal names\n\
9574 may be interspersed with actions, with the actions being performed for\n\
9575 all signals cumulatively specified."));
9576 set_cmd_completer (c
, handle_completer
);
9579 stop_command
= add_cmd ("stop", class_obscure
,
9580 not_just_help_class_command
, _("\
9581 There is no `stop' command, but you can set a hook on `stop'.\n\
9582 This allows you to set a list of commands to be run each time execution\n\
9583 of the program stops."), &cmdlist
);
9585 add_setshow_boolean_cmd
9586 ("infrun", class_maintenance
, &debug_infrun
,
9587 _("Set inferior debugging."),
9588 _("Show inferior debugging."),
9589 _("When non-zero, inferior specific debugging is enabled."),
9590 NULL
, show_debug_infrun
, &setdebuglist
, &showdebuglist
);
9592 add_setshow_boolean_cmd ("non-stop", no_class
,
9594 Set whether gdb controls the inferior in non-stop mode."), _("\
9595 Show whether gdb controls the inferior in non-stop mode."), _("\
9596 When debugging a multi-threaded program and this setting is\n\
9597 off (the default, also called all-stop mode), when one thread stops\n\
9598 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9599 all other threads in the program while you interact with the thread of\n\
9600 interest. When you continue or step a thread, you can allow the other\n\
9601 threads to run, or have them remain stopped, but while you inspect any\n\
9602 thread's state, all threads stop.\n\
9604 In non-stop mode, when one thread stops, other threads can continue\n\
9605 to run freely. You'll be able to step each thread independently,\n\
9606 leave it stopped or free to run as needed."),
9612 for (size_t i
= 0; i
< GDB_SIGNAL_LAST
; i
++)
9615 signal_print
[i
] = 1;
9616 signal_program
[i
] = 1;
9617 signal_catch
[i
] = 0;
9620 /* Signals caused by debugger's own actions should not be given to
9621 the program afterwards.
9623 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9624 explicitly specifies that it should be delivered to the target
9625 program. Typically, that would occur when a user is debugging a
9626 target monitor on a simulator: the target monitor sets a
9627 breakpoint; the simulator encounters this breakpoint and halts
9628 the simulation handing control to GDB; GDB, noting that the stop
9629 address doesn't map to any known breakpoint, returns control back
9630 to the simulator; the simulator then delivers the hardware
9631 equivalent of a GDB_SIGNAL_TRAP to the program being
9633 signal_program
[GDB_SIGNAL_TRAP
] = 0;
9634 signal_program
[GDB_SIGNAL_INT
] = 0;
9636 /* Signals that are not errors should not normally enter the debugger. */
9637 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
9638 signal_print
[GDB_SIGNAL_ALRM
] = 0;
9639 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
9640 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
9641 signal_stop
[GDB_SIGNAL_PROF
] = 0;
9642 signal_print
[GDB_SIGNAL_PROF
] = 0;
9643 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
9644 signal_print
[GDB_SIGNAL_CHLD
] = 0;
9645 signal_stop
[GDB_SIGNAL_IO
] = 0;
9646 signal_print
[GDB_SIGNAL_IO
] = 0;
9647 signal_stop
[GDB_SIGNAL_POLL
] = 0;
9648 signal_print
[GDB_SIGNAL_POLL
] = 0;
9649 signal_stop
[GDB_SIGNAL_URG
] = 0;
9650 signal_print
[GDB_SIGNAL_URG
] = 0;
9651 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
9652 signal_print
[GDB_SIGNAL_WINCH
] = 0;
9653 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
9654 signal_print
[GDB_SIGNAL_PRIO
] = 0;
9656 /* These signals are used internally by user-level thread
9657 implementations. (See signal(5) on Solaris.) Like the above
9658 signals, a healthy program receives and handles them as part of
9659 its normal operation. */
9660 signal_stop
[GDB_SIGNAL_LWP
] = 0;
9661 signal_print
[GDB_SIGNAL_LWP
] = 0;
9662 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
9663 signal_print
[GDB_SIGNAL_WAITING
] = 0;
9664 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
9665 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
9666 signal_stop
[GDB_SIGNAL_LIBRT
] = 0;
9667 signal_print
[GDB_SIGNAL_LIBRT
] = 0;
9669 /* Update cached state. */
9670 signal_cache_update (-1);
9672 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
9673 &stop_on_solib_events
, _("\
9674 Set stopping for shared library events."), _("\
9675 Show stopping for shared library events."), _("\
9676 If nonzero, gdb will give control to the user when the dynamic linker\n\
9677 notifies gdb of shared library events. The most common event of interest\n\
9678 to the user would be loading/unloading of a new library."),
9679 set_stop_on_solib_events
,
9680 show_stop_on_solib_events
,
9681 &setlist
, &showlist
);
9683 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
9684 follow_fork_mode_kind_names
,
9685 &follow_fork_mode_string
, _("\
9686 Set debugger response to a program call of fork or vfork."), _("\
9687 Show debugger response to a program call of fork or vfork."), _("\
9688 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9689 parent - the original process is debugged after a fork\n\
9690 child - the new process is debugged after a fork\n\
9691 The unfollowed process will continue to run.\n\
9692 By default, the debugger will follow the parent process."),
9694 show_follow_fork_mode_string
,
9695 &setlist
, &showlist
);
9697 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
9698 follow_exec_mode_names
,
9699 &follow_exec_mode_string
, _("\
9700 Set debugger response to a program call of exec."), _("\
9701 Show debugger response to a program call of exec."), _("\
9702 An exec call replaces the program image of a process.\n\
9704 follow-exec-mode can be:\n\
9706 new - the debugger creates a new inferior and rebinds the process\n\
9707 to this new inferior. The program the process was running before\n\
9708 the exec call can be restarted afterwards by restarting the original\n\
9711 same - the debugger keeps the process bound to the same inferior.\n\
9712 The new executable image replaces the previous executable loaded in\n\
9713 the inferior. Restarting the inferior after the exec call restarts\n\
9714 the executable the process was running after the exec call.\n\
9716 By default, the debugger will use the same inferior."),
9718 show_follow_exec_mode_string
,
9719 &setlist
, &showlist
);
9721 add_setshow_enum_cmd ("scheduler-locking", class_run
,
9722 scheduler_enums
, &scheduler_mode
, _("\
9723 Set mode for locking scheduler during execution."), _("\
9724 Show mode for locking scheduler during execution."), _("\
9725 off == no locking (threads may preempt at any time)\n\
9726 on == full locking (no thread except the current thread may run)\n\
9727 This applies to both normal execution and replay mode.\n\
9728 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9729 In this mode, other threads may run during other commands.\n\
9730 This applies to both normal execution and replay mode.\n\
9731 replay == scheduler locked in replay mode and unlocked during normal execution."),
9732 set_schedlock_func
, /* traps on target vector */
9733 show_scheduler_mode
,
9734 &setlist
, &showlist
);
9736 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
9737 Set mode for resuming threads of all processes."), _("\
9738 Show mode for resuming threads of all processes."), _("\
9739 When on, execution commands (such as 'continue' or 'next') resume all\n\
9740 threads of all processes. When off (which is the default), execution\n\
9741 commands only resume the threads of the current process. The set of\n\
9742 threads that are resumed is further refined by the scheduler-locking\n\
9743 mode (see help set scheduler-locking)."),
9745 show_schedule_multiple
,
9746 &setlist
, &showlist
);
9748 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
9749 Set mode of the step operation."), _("\
9750 Show mode of the step operation."), _("\
9751 When set, doing a step over a function without debug line information\n\
9752 will stop at the first instruction of that function. Otherwise, the\n\
9753 function is skipped and the step command stops at a different source line."),
9755 show_step_stop_if_no_debug
,
9756 &setlist
, &showlist
);
9758 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
9759 &can_use_displaced_stepping
, _("\
9760 Set debugger's willingness to use displaced stepping."), _("\
9761 Show debugger's willingness to use displaced stepping."), _("\
9762 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9763 supported by the target architecture. If off, gdb will not use displaced\n\
9764 stepping to step over breakpoints, even if such is supported by the target\n\
9765 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9766 if the target architecture supports it and non-stop mode is active, but will not\n\
9767 use it in all-stop mode (see help set non-stop)."),
9769 show_can_use_displaced_stepping
,
9770 &setlist
, &showlist
);
9772 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
9773 &exec_direction
, _("Set direction of execution.\n\
9774 Options are 'forward' or 'reverse'."),
9775 _("Show direction of execution (forward/reverse)."),
9776 _("Tells gdb whether to execute forward or backward."),
9777 set_exec_direction_func
, show_exec_direction_func
,
9778 &setlist
, &showlist
);
9780 /* Set/show detach-on-fork: user-settable mode. */
9782 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
9783 Set whether gdb will detach the child of a fork."), _("\
9784 Show whether gdb will detach the child of a fork."), _("\
9785 Tells gdb whether to detach the child of a fork."),
9786 NULL
, NULL
, &setlist
, &showlist
);
9788 /* Set/show disable address space randomization mode. */
9790 add_setshow_boolean_cmd ("disable-randomization", class_support
,
9791 &disable_randomization
, _("\
9792 Set disabling of debuggee's virtual address space randomization."), _("\
9793 Show disabling of debuggee's virtual address space randomization."), _("\
9794 When this mode is on (which is the default), randomization of the virtual\n\
9795 address space is disabled. Standalone programs run with the randomization\n\
9796 enabled by default on some platforms."),
9797 &set_disable_randomization
,
9798 &show_disable_randomization
,
9799 &setlist
, &showlist
);
9801 /* ptid initializations */
9802 inferior_ptid
= null_ptid
;
9803 target_last_wait_ptid
= minus_one_ptid
;
9805 gdb::observers::thread_ptid_changed
.attach (infrun_thread_ptid_changed
,
9807 gdb::observers::thread_stop_requested
.attach (infrun_thread_stop_requested
,
9809 gdb::observers::thread_exit
.attach (infrun_thread_thread_exit
, "infrun");
9810 gdb::observers::inferior_exit
.attach (infrun_inferior_exit
, "infrun");
9811 gdb::observers::inferior_execd
.attach (infrun_inferior_execd
, "infrun");
9813 /* Explicitly create without lookup, since that tries to create a
9814 value with a void typed value, and when we get here, gdbarch
9815 isn't initialized yet. At this point, we're quite sure there
9816 isn't another convenience variable of the same name. */
9817 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
9819 add_setshow_boolean_cmd ("observer", no_class
,
9820 &observer_mode_1
, _("\
9821 Set whether gdb controls the inferior in observer mode."), _("\
9822 Show whether gdb controls the inferior in observer mode."), _("\
9823 In observer mode, GDB can get data from the inferior, but not\n\
9824 affect its execution. Registers and memory may not be changed,\n\
9825 breakpoints may not be set, and the program cannot be interrupted\n\
9833 selftests::register_test ("infrun_thread_ptid_changed",
9834 selftests::infrun_thread_ptid_changed
);