1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2021 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
22 #include "displaced-stepping.h"
28 #include "breakpoint.h"
32 #include "target-connection.h"
33 #include "gdbthread.h"
40 #include "observable.h"
45 #include "mi/mi-common.h"
46 #include "event-top.h"
48 #include "record-full.h"
49 #include "inline-frame.h"
51 #include "tracepoint.h"
55 #include "completer.h"
56 #include "target-descriptions.h"
57 #include "target-dcache.h"
60 #include "gdbsupport/event-loop.h"
61 #include "thread-fsm.h"
62 #include "gdbsupport/enum-flags.h"
63 #include "progspace-and-thread.h"
64 #include "gdbsupport/gdb_optional.h"
65 #include "arch-utils.h"
66 #include "gdbsupport/scope-exit.h"
67 #include "gdbsupport/forward-scope-exit.h"
68 #include "gdbsupport/gdb_select.h"
69 #include <unordered_map>
70 #include "async-event.h"
71 #include "gdbsupport/selftest.h"
72 #include "scoped-mock-context.h"
73 #include "test-target.h"
74 #include "gdbsupport/common-debug.h"
76 /* Prototypes for local functions */
78 static void sig_print_info (enum gdb_signal
);
80 static void sig_print_header (void);
82 static void follow_inferior_reset_breakpoints (void);
84 static bool currently_stepping (struct thread_info
*tp
);
86 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*);
88 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
90 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
92 static bool maybe_software_singlestep (struct gdbarch
*gdbarch
);
94 static void resume (gdb_signal sig
);
96 static void wait_for_inferior (inferior
*inf
);
98 /* Asynchronous signal handler registered as event loop source for
99 when we have pending events ready to be passed to the core. */
100 static struct async_event_handler
*infrun_async_inferior_event_token
;
102 /* Stores whether infrun_async was previously enabled or disabled.
103 Starts off as -1, indicating "never enabled/disabled". */
104 static int infrun_is_async
= -1;
109 infrun_async (int enable
)
111 if (infrun_is_async
!= enable
)
113 infrun_is_async
= enable
;
115 infrun_debug_printf ("enable=%d", enable
);
118 mark_async_event_handler (infrun_async_inferior_event_token
);
120 clear_async_event_handler (infrun_async_inferior_event_token
);
127 mark_infrun_async_event_handler (void)
129 mark_async_event_handler (infrun_async_inferior_event_token
);
132 /* When set, stop the 'step' command if we enter a function which has
133 no line number information. The normal behavior is that we step
134 over such function. */
135 bool step_stop_if_no_debug
= false;
137 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
138 struct cmd_list_element
*c
, const char *value
)
140 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
143 /* proceed and normal_stop use this to notify the user when the
144 inferior stopped in a different thread than it had been running
147 static ptid_t previous_inferior_ptid
;
149 /* If set (default for legacy reasons), when following a fork, GDB
150 will detach from one of the fork branches, child or parent.
151 Exactly which branch is detached depends on 'set follow-fork-mode'
154 static bool detach_fork
= true;
156 bool debug_infrun
= false;
158 show_debug_infrun (struct ui_file
*file
, int from_tty
,
159 struct cmd_list_element
*c
, const char *value
)
161 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
164 /* Support for disabling address space randomization. */
166 bool disable_randomization
= true;
169 show_disable_randomization (struct ui_file
*file
, int from_tty
,
170 struct cmd_list_element
*c
, const char *value
)
172 if (target_supports_disable_randomization ())
173 fprintf_filtered (file
,
174 _("Disabling randomization of debuggee's "
175 "virtual address space is %s.\n"),
178 fputs_filtered (_("Disabling randomization of debuggee's "
179 "virtual address space is unsupported on\n"
180 "this platform.\n"), file
);
184 set_disable_randomization (const char *args
, int from_tty
,
185 struct cmd_list_element
*c
)
187 if (!target_supports_disable_randomization ())
188 error (_("Disabling randomization of debuggee's "
189 "virtual address space is unsupported on\n"
193 /* User interface for non-stop mode. */
195 bool non_stop
= false;
196 static bool non_stop_1
= false;
199 set_non_stop (const char *args
, int from_tty
,
200 struct cmd_list_element
*c
)
202 if (target_has_execution ())
204 non_stop_1
= non_stop
;
205 error (_("Cannot change this setting while the inferior is running."));
208 non_stop
= non_stop_1
;
212 show_non_stop (struct ui_file
*file
, int from_tty
,
213 struct cmd_list_element
*c
, const char *value
)
215 fprintf_filtered (file
,
216 _("Controlling the inferior in non-stop mode is %s.\n"),
220 /* "Observer mode" is somewhat like a more extreme version of
221 non-stop, in which all GDB operations that might affect the
222 target's execution have been disabled. */
224 static bool observer_mode
= false;
225 static bool observer_mode_1
= false;
228 set_observer_mode (const char *args
, int from_tty
,
229 struct cmd_list_element
*c
)
231 if (target_has_execution ())
233 observer_mode_1
= observer_mode
;
234 error (_("Cannot change this setting while the inferior is running."));
237 observer_mode
= observer_mode_1
;
239 may_write_registers
= !observer_mode
;
240 may_write_memory
= !observer_mode
;
241 may_insert_breakpoints
= !observer_mode
;
242 may_insert_tracepoints
= !observer_mode
;
243 /* We can insert fast tracepoints in or out of observer mode,
244 but enable them if we're going into this mode. */
246 may_insert_fast_tracepoints
= true;
247 may_stop
= !observer_mode
;
248 update_target_permissions ();
250 /* Going *into* observer mode we must force non-stop, then
251 going out we leave it that way. */
254 pagination_enabled
= 0;
255 non_stop
= non_stop_1
= true;
259 printf_filtered (_("Observer mode is now %s.\n"),
260 (observer_mode
? "on" : "off"));
264 show_observer_mode (struct ui_file
*file
, int from_tty
,
265 struct cmd_list_element
*c
, const char *value
)
267 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
270 /* This updates the value of observer mode based on changes in
271 permissions. Note that we are deliberately ignoring the values of
272 may-write-registers and may-write-memory, since the user may have
273 reason to enable these during a session, for instance to turn on a
274 debugging-related global. */
277 update_observer_mode (void)
279 bool newval
= (!may_insert_breakpoints
280 && !may_insert_tracepoints
281 && may_insert_fast_tracepoints
285 /* Let the user know if things change. */
286 if (newval
!= observer_mode
)
287 printf_filtered (_("Observer mode is now %s.\n"),
288 (newval
? "on" : "off"));
290 observer_mode
= observer_mode_1
= newval
;
293 /* Tables of how to react to signals; the user sets them. */
295 static unsigned char signal_stop
[GDB_SIGNAL_LAST
];
296 static unsigned char signal_print
[GDB_SIGNAL_LAST
];
297 static unsigned char signal_program
[GDB_SIGNAL_LAST
];
299 /* Table of signals that are registered with "catch signal". A
300 non-zero entry indicates that the signal is caught by some "catch
302 static unsigned char signal_catch
[GDB_SIGNAL_LAST
];
304 /* Table of signals that the target may silently handle.
305 This is automatically determined from the flags above,
306 and simply cached here. */
307 static unsigned char signal_pass
[GDB_SIGNAL_LAST
];
309 #define SET_SIGS(nsigs,sigs,flags) \
311 int signum = (nsigs); \
312 while (signum-- > 0) \
313 if ((sigs)[signum]) \
314 (flags)[signum] = 1; \
317 #define UNSET_SIGS(nsigs,sigs,flags) \
319 int signum = (nsigs); \
320 while (signum-- > 0) \
321 if ((sigs)[signum]) \
322 (flags)[signum] = 0; \
325 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
326 this function is to avoid exporting `signal_program'. */
329 update_signals_program_target (void)
331 target_program_signals (signal_program
);
334 /* Value to pass to target_resume() to cause all threads to resume. */
336 #define RESUME_ALL minus_one_ptid
338 /* Command list pointer for the "stop" placeholder. */
340 static struct cmd_list_element
*stop_command
;
342 /* Nonzero if we want to give control to the user when we're notified
343 of shared library events by the dynamic linker. */
344 int stop_on_solib_events
;
346 /* Enable or disable optional shared library event breakpoints
347 as appropriate when the above flag is changed. */
350 set_stop_on_solib_events (const char *args
,
351 int from_tty
, struct cmd_list_element
*c
)
353 update_solib_breakpoints ();
357 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
358 struct cmd_list_element
*c
, const char *value
)
360 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
364 /* True after stop if current stack frame should be printed. */
366 static bool stop_print_frame
;
368 /* This is a cached copy of the target/ptid/waitstatus of the last
369 event returned by target_wait()/deprecated_target_wait_hook().
370 This information is returned by get_last_target_status(). */
371 static process_stratum_target
*target_last_proc_target
;
372 static ptid_t target_last_wait_ptid
;
373 static struct target_waitstatus target_last_waitstatus
;
375 void init_thread_stepping_state (struct thread_info
*tss
);
377 static const char follow_fork_mode_child
[] = "child";
378 static const char follow_fork_mode_parent
[] = "parent";
380 static const char *const follow_fork_mode_kind_names
[] = {
381 follow_fork_mode_child
,
382 follow_fork_mode_parent
,
386 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
388 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
389 struct cmd_list_element
*c
, const char *value
)
391 fprintf_filtered (file
,
392 _("Debugger response to a program "
393 "call of fork or vfork is \"%s\".\n"),
398 /* Handle changes to the inferior list based on the type of fork,
399 which process is being followed, and whether the other process
400 should be detached. On entry inferior_ptid must be the ptid of
401 the fork parent. At return inferior_ptid is the ptid of the
402 followed inferior. */
405 follow_fork_inferior (bool follow_child
, bool detach_fork
)
408 ptid_t parent_ptid
, child_ptid
;
410 has_vforked
= (inferior_thread ()->pending_follow
.kind
411 == TARGET_WAITKIND_VFORKED
);
412 parent_ptid
= inferior_ptid
;
413 child_ptid
= inferior_thread ()->pending_follow
.value
.related_pid
;
416 && !non_stop
/* Non-stop always resumes both branches. */
417 && current_ui
->prompt_state
== PROMPT_BLOCKED
418 && !(follow_child
|| detach_fork
|| sched_multi
))
420 /* The parent stays blocked inside the vfork syscall until the
421 child execs or exits. If we don't let the child run, then
422 the parent stays blocked. If we're telling the parent to run
423 in the foreground, the user will not be able to ctrl-c to get
424 back the terminal, effectively hanging the debug session. */
425 fprintf_filtered (gdb_stderr
, _("\
426 Can not resume the parent process over vfork in the foreground while\n\
427 holding the child stopped. Try \"set detach-on-fork\" or \
428 \"set schedule-multiple\".\n"));
434 /* Detach new forked process? */
437 /* Before detaching from the child, remove all breakpoints
438 from it. If we forked, then this has already been taken
439 care of by infrun.c. If we vforked however, any
440 breakpoint inserted in the parent is visible in the
441 child, even those added while stopped in a vfork
442 catchpoint. This will remove the breakpoints from the
443 parent also, but they'll be reinserted below. */
446 /* Keep breakpoints list in sync. */
447 remove_breakpoints_inf (current_inferior ());
450 if (print_inferior_events
)
452 /* Ensure that we have a process ptid. */
453 ptid_t process_ptid
= ptid_t (child_ptid
.pid ());
455 target_terminal::ours_for_output ();
456 fprintf_filtered (gdb_stdlog
,
457 _("[Detaching after %s from child %s]\n"),
458 has_vforked
? "vfork" : "fork",
459 target_pid_to_str (process_ptid
).c_str ());
464 struct inferior
*parent_inf
, *child_inf
;
466 /* Add process to GDB's tables. */
467 child_inf
= add_inferior (child_ptid
.pid ());
469 parent_inf
= current_inferior ();
470 child_inf
->attach_flag
= parent_inf
->attach_flag
;
471 copy_terminal_info (child_inf
, parent_inf
);
472 child_inf
->gdbarch
= parent_inf
->gdbarch
;
473 copy_inferior_target_desc_info (child_inf
, parent_inf
);
475 scoped_restore_current_pspace_and_thread restore_pspace_thread
;
477 set_current_inferior (child_inf
);
478 switch_to_no_thread ();
479 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
480 child_inf
->push_target (parent_inf
->process_target ());
481 thread_info
*child_thr
482 = add_thread_silent (child_inf
->process_target (), child_ptid
);
484 /* If this is a vfork child, then the address-space is
485 shared with the parent. */
488 child_inf
->pspace
= parent_inf
->pspace
;
489 child_inf
->aspace
= parent_inf
->aspace
;
493 /* The parent will be frozen until the child is done
494 with the shared region. Keep track of the
496 child_inf
->vfork_parent
= parent_inf
;
497 child_inf
->pending_detach
= 0;
498 parent_inf
->vfork_child
= child_inf
;
499 parent_inf
->pending_detach
= 0;
501 /* Now that the inferiors and program spaces are all
502 wired up, we can switch to the child thread (which
503 switches inferior and program space too). */
504 switch_to_thread (child_thr
);
508 child_inf
->aspace
= new_address_space ();
509 child_inf
->pspace
= new program_space (child_inf
->aspace
);
510 child_inf
->removable
= 1;
511 set_current_program_space (child_inf
->pspace
);
512 clone_program_space (child_inf
->pspace
, parent_inf
->pspace
);
514 /* solib_create_inferior_hook relies on the current
516 switch_to_thread (child_thr
);
518 /* Let the shared library layer (e.g., solib-svr4) learn
519 about this new process, relocate the cloned exec, pull
520 in shared libraries, and install the solib event
521 breakpoint. If a "cloned-VM" event was propagated
522 better throughout the core, this wouldn't be
524 scoped_restore restore_in_initial_library_scan
525 = make_scoped_restore (&child_inf
->in_initial_library_scan
,
527 solib_create_inferior_hook (0);
533 struct inferior
*parent_inf
;
535 parent_inf
= current_inferior ();
537 /* If we detached from the child, then we have to be careful
538 to not insert breakpoints in the parent until the child
539 is done with the shared memory region. However, if we're
540 staying attached to the child, then we can and should
541 insert breakpoints, so that we can debug it. A
542 subsequent child exec or exit is enough to know when does
543 the child stops using the parent's address space. */
544 parent_inf
->waiting_for_vfork_done
= detach_fork
;
545 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
550 /* Follow the child. */
551 struct inferior
*parent_inf
, *child_inf
;
552 struct program_space
*parent_pspace
;
554 if (print_inferior_events
)
556 std::string parent_pid
= target_pid_to_str (parent_ptid
);
557 std::string child_pid
= target_pid_to_str (child_ptid
);
559 target_terminal::ours_for_output ();
560 fprintf_filtered (gdb_stdlog
,
561 _("[Attaching after %s %s to child %s]\n"),
563 has_vforked
? "vfork" : "fork",
567 /* Add the new inferior first, so that the target_detach below
568 doesn't unpush the target. */
570 child_inf
= add_inferior (child_ptid
.pid ());
572 parent_inf
= current_inferior ();
573 child_inf
->attach_flag
= parent_inf
->attach_flag
;
574 copy_terminal_info (child_inf
, parent_inf
);
575 child_inf
->gdbarch
= parent_inf
->gdbarch
;
576 copy_inferior_target_desc_info (child_inf
, parent_inf
);
578 parent_pspace
= parent_inf
->pspace
;
580 process_stratum_target
*target
= parent_inf
->process_target ();
583 /* Hold a strong reference to the target while (maybe)
584 detaching the parent. Otherwise detaching could close the
586 auto target_ref
= target_ops_ref::new_reference (target
);
588 /* If we're vforking, we want to hold on to the parent until
589 the child exits or execs. At child exec or exit time we
590 can remove the old breakpoints from the parent and detach
591 or resume debugging it. Otherwise, detach the parent now;
592 we'll want to reuse it's program/address spaces, but we
593 can't set them to the child before removing breakpoints
594 from the parent, otherwise, the breakpoints module could
595 decide to remove breakpoints from the wrong process (since
596 they'd be assigned to the same address space). */
600 gdb_assert (child_inf
->vfork_parent
== NULL
);
601 gdb_assert (parent_inf
->vfork_child
== NULL
);
602 child_inf
->vfork_parent
= parent_inf
;
603 child_inf
->pending_detach
= 0;
604 parent_inf
->vfork_child
= child_inf
;
605 parent_inf
->pending_detach
= detach_fork
;
606 parent_inf
->waiting_for_vfork_done
= 0;
608 else if (detach_fork
)
610 if (print_inferior_events
)
612 /* Ensure that we have a process ptid. */
613 ptid_t process_ptid
= ptid_t (parent_ptid
.pid ());
615 target_terminal::ours_for_output ();
616 fprintf_filtered (gdb_stdlog
,
617 _("[Detaching after fork from "
619 target_pid_to_str (process_ptid
).c_str ());
622 target_detach (parent_inf
, 0);
626 /* Note that the detach above makes PARENT_INF dangling. */
628 /* Add the child thread to the appropriate lists, and switch
629 to this new thread, before cloning the program space, and
630 informing the solib layer about this new process. */
632 set_current_inferior (child_inf
);
633 child_inf
->push_target (target
);
636 thread_info
*child_thr
= add_thread_silent (target
, child_ptid
);
638 /* If this is a vfork child, then the address-space is shared
639 with the parent. If we detached from the parent, then we can
640 reuse the parent's program/address spaces. */
641 if (has_vforked
|| detach_fork
)
643 child_inf
->pspace
= parent_pspace
;
644 child_inf
->aspace
= child_inf
->pspace
->aspace
;
650 child_inf
->aspace
= new_address_space ();
651 child_inf
->pspace
= new program_space (child_inf
->aspace
);
652 child_inf
->removable
= 1;
653 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
654 set_current_program_space (child_inf
->pspace
);
655 clone_program_space (child_inf
->pspace
, parent_pspace
);
657 /* Let the shared library layer (e.g., solib-svr4) learn
658 about this new process, relocate the cloned exec, pull in
659 shared libraries, and install the solib event breakpoint.
660 If a "cloned-VM" event was propagated better throughout
661 the core, this wouldn't be required. */
662 scoped_restore restore_in_initial_library_scan
663 = make_scoped_restore (&child_inf
->in_initial_library_scan
, true);
664 solib_create_inferior_hook (0);
667 switch_to_thread (child_thr
);
670 target_follow_fork (follow_child
, detach_fork
);
675 /* Tell the target to follow the fork we're stopped at. Returns true
676 if the inferior should be resumed; false, if the target for some
677 reason decided it's best not to resume. */
682 bool follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
683 bool should_resume
= true;
684 struct thread_info
*tp
;
686 /* Copy user stepping state to the new inferior thread. FIXME: the
687 followed fork child thread should have a copy of most of the
688 parent thread structure's run control related fields, not just these.
689 Initialized to avoid "may be used uninitialized" warnings from gcc. */
690 struct breakpoint
*step_resume_breakpoint
= NULL
;
691 struct breakpoint
*exception_resume_breakpoint
= NULL
;
692 CORE_ADDR step_range_start
= 0;
693 CORE_ADDR step_range_end
= 0;
694 int current_line
= 0;
695 symtab
*current_symtab
= NULL
;
696 struct frame_id step_frame_id
= { 0 };
697 struct thread_fsm
*thread_fsm
= NULL
;
701 process_stratum_target
*wait_target
;
703 struct target_waitstatus wait_status
;
705 /* Get the last target status returned by target_wait(). */
706 get_last_target_status (&wait_target
, &wait_ptid
, &wait_status
);
708 /* If not stopped at a fork event, then there's nothing else to
710 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
711 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
714 /* Check if we switched over from WAIT_PTID, since the event was
716 if (wait_ptid
!= minus_one_ptid
717 && (current_inferior ()->process_target () != wait_target
718 || inferior_ptid
!= wait_ptid
))
720 /* We did. Switch back to WAIT_PTID thread, to tell the
721 target to follow it (in either direction). We'll
722 afterwards refuse to resume, and inform the user what
724 thread_info
*wait_thread
= find_thread_ptid (wait_target
, wait_ptid
);
725 switch_to_thread (wait_thread
);
726 should_resume
= false;
730 tp
= inferior_thread ();
732 /* If there were any forks/vforks that were caught and are now to be
733 followed, then do so now. */
734 switch (tp
->pending_follow
.kind
)
736 case TARGET_WAITKIND_FORKED
:
737 case TARGET_WAITKIND_VFORKED
:
739 ptid_t parent
, child
;
741 /* If the user did a next/step, etc, over a fork call,
742 preserve the stepping state in the fork child. */
743 if (follow_child
&& should_resume
)
745 step_resume_breakpoint
= clone_momentary_breakpoint
746 (tp
->control
.step_resume_breakpoint
);
747 step_range_start
= tp
->control
.step_range_start
;
748 step_range_end
= tp
->control
.step_range_end
;
749 current_line
= tp
->current_line
;
750 current_symtab
= tp
->current_symtab
;
751 step_frame_id
= tp
->control
.step_frame_id
;
752 exception_resume_breakpoint
753 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
754 thread_fsm
= tp
->thread_fsm
;
756 /* For now, delete the parent's sr breakpoint, otherwise,
757 parent/child sr breakpoints are considered duplicates,
758 and the child version will not be installed. Remove
759 this when the breakpoints module becomes aware of
760 inferiors and address spaces. */
761 delete_step_resume_breakpoint (tp
);
762 tp
->control
.step_range_start
= 0;
763 tp
->control
.step_range_end
= 0;
764 tp
->control
.step_frame_id
= null_frame_id
;
765 delete_exception_resume_breakpoint (tp
);
766 tp
->thread_fsm
= NULL
;
769 parent
= inferior_ptid
;
770 child
= tp
->pending_follow
.value
.related_pid
;
772 process_stratum_target
*parent_targ
= tp
->inf
->process_target ();
773 /* Set up inferior(s) as specified by the caller, and tell the
774 target to do whatever is necessary to follow either parent
776 if (follow_fork_inferior (follow_child
, detach_fork
))
778 /* Target refused to follow, or there's some other reason
779 we shouldn't resume. */
784 /* This pending follow fork event is now handled, one way
785 or another. The previous selected thread may be gone
786 from the lists by now, but if it is still around, need
787 to clear the pending follow request. */
788 tp
= find_thread_ptid (parent_targ
, parent
);
790 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
792 /* This makes sure we don't try to apply the "Switched
793 over from WAIT_PID" logic above. */
794 nullify_last_target_wait_ptid ();
796 /* If we followed the child, switch to it... */
799 thread_info
*child_thr
= find_thread_ptid (parent_targ
, child
);
800 switch_to_thread (child_thr
);
802 /* ... and preserve the stepping state, in case the
803 user was stepping over the fork call. */
806 tp
= inferior_thread ();
807 tp
->control
.step_resume_breakpoint
808 = step_resume_breakpoint
;
809 tp
->control
.step_range_start
= step_range_start
;
810 tp
->control
.step_range_end
= step_range_end
;
811 tp
->current_line
= current_line
;
812 tp
->current_symtab
= current_symtab
;
813 tp
->control
.step_frame_id
= step_frame_id
;
814 tp
->control
.exception_resume_breakpoint
815 = exception_resume_breakpoint
;
816 tp
->thread_fsm
= thread_fsm
;
820 /* If we get here, it was because we're trying to
821 resume from a fork catchpoint, but, the user
822 has switched threads away from the thread that
823 forked. In that case, the resume command
824 issued is most likely not applicable to the
825 child, so just warn, and refuse to resume. */
826 warning (_("Not resuming: switched threads "
827 "before following fork child."));
830 /* Reset breakpoints in the child as appropriate. */
831 follow_inferior_reset_breakpoints ();
836 case TARGET_WAITKIND_SPURIOUS
:
837 /* Nothing to follow. */
840 internal_error (__FILE__
, __LINE__
,
841 "Unexpected pending_follow.kind %d\n",
842 tp
->pending_follow
.kind
);
846 return should_resume
;
850 follow_inferior_reset_breakpoints (void)
852 struct thread_info
*tp
= inferior_thread ();
854 /* Was there a step_resume breakpoint? (There was if the user
855 did a "next" at the fork() call.) If so, explicitly reset its
856 thread number. Cloned step_resume breakpoints are disabled on
857 creation, so enable it here now that it is associated with the
860 step_resumes are a form of bp that are made to be per-thread.
861 Since we created the step_resume bp when the parent process
862 was being debugged, and now are switching to the child process,
863 from the breakpoint package's viewpoint, that's a switch of
864 "threads". We must update the bp's notion of which thread
865 it is for, or it'll be ignored when it triggers. */
867 if (tp
->control
.step_resume_breakpoint
)
869 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
870 tp
->control
.step_resume_breakpoint
->loc
->enabled
= 1;
873 /* Treat exception_resume breakpoints like step_resume breakpoints. */
874 if (tp
->control
.exception_resume_breakpoint
)
876 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
877 tp
->control
.exception_resume_breakpoint
->loc
->enabled
= 1;
880 /* Reinsert all breakpoints in the child. The user may have set
881 breakpoints after catching the fork, in which case those
882 were never set in the child, but only in the parent. This makes
883 sure the inserted breakpoints match the breakpoint list. */
885 breakpoint_re_set ();
886 insert_breakpoints ();
889 /* The child has exited or execed: resume threads of the parent the
890 user wanted to be executing. */
893 proceed_after_vfork_done (struct thread_info
*thread
,
896 int pid
= * (int *) arg
;
898 if (thread
->ptid
.pid () == pid
899 && thread
->state
== THREAD_RUNNING
900 && !thread
->executing
901 && !thread
->stop_requested
902 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
904 infrun_debug_printf ("resuming vfork parent thread %s",
905 target_pid_to_str (thread
->ptid
).c_str ());
907 switch_to_thread (thread
);
908 clear_proceed_status (0);
909 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
);
915 /* Called whenever we notice an exec or exit event, to handle
916 detaching or resuming a vfork parent. */
919 handle_vfork_child_exec_or_exit (int exec
)
921 struct inferior
*inf
= current_inferior ();
923 if (inf
->vfork_parent
)
925 int resume_parent
= -1;
927 /* This exec or exit marks the end of the shared memory region
928 between the parent and the child. Break the bonds. */
929 inferior
*vfork_parent
= inf
->vfork_parent
;
930 inf
->vfork_parent
->vfork_child
= NULL
;
931 inf
->vfork_parent
= NULL
;
933 /* If the user wanted to detach from the parent, now is the
935 if (vfork_parent
->pending_detach
)
937 struct program_space
*pspace
;
938 struct address_space
*aspace
;
940 /* follow-fork child, detach-on-fork on. */
942 vfork_parent
->pending_detach
= 0;
944 scoped_restore_current_pspace_and_thread restore_thread
;
946 /* We're letting loose of the parent. */
947 thread_info
*tp
= any_live_thread_of_inferior (vfork_parent
);
948 switch_to_thread (tp
);
950 /* We're about to detach from the parent, which implicitly
951 removes breakpoints from its address space. There's a
952 catch here: we want to reuse the spaces for the child,
953 but, parent/child are still sharing the pspace at this
954 point, although the exec in reality makes the kernel give
955 the child a fresh set of new pages. The problem here is
956 that the breakpoints module being unaware of this, would
957 likely chose the child process to write to the parent
958 address space. Swapping the child temporarily away from
959 the spaces has the desired effect. Yes, this is "sort
962 pspace
= inf
->pspace
;
963 aspace
= inf
->aspace
;
967 if (print_inferior_events
)
970 = target_pid_to_str (ptid_t (vfork_parent
->pid
));
972 target_terminal::ours_for_output ();
976 fprintf_filtered (gdb_stdlog
,
977 _("[Detaching vfork parent %s "
978 "after child exec]\n"), pidstr
.c_str ());
982 fprintf_filtered (gdb_stdlog
,
983 _("[Detaching vfork parent %s "
984 "after child exit]\n"), pidstr
.c_str ());
988 target_detach (vfork_parent
, 0);
991 inf
->pspace
= pspace
;
992 inf
->aspace
= aspace
;
996 /* We're staying attached to the parent, so, really give the
997 child a new address space. */
998 inf
->pspace
= new program_space (maybe_new_address_space ());
999 inf
->aspace
= inf
->pspace
->aspace
;
1001 set_current_program_space (inf
->pspace
);
1003 resume_parent
= vfork_parent
->pid
;
1007 /* If this is a vfork child exiting, then the pspace and
1008 aspaces were shared with the parent. Since we're
1009 reporting the process exit, we'll be mourning all that is
1010 found in the address space, and switching to null_ptid,
1011 preparing to start a new inferior. But, since we don't
1012 want to clobber the parent's address/program spaces, we
1013 go ahead and create a new one for this exiting
1016 /* Switch to no-thread while running clone_program_space, so
1017 that clone_program_space doesn't want to read the
1018 selected frame of a dead process. */
1019 scoped_restore_current_thread restore_thread
;
1020 switch_to_no_thread ();
1022 inf
->pspace
= new program_space (maybe_new_address_space ());
1023 inf
->aspace
= inf
->pspace
->aspace
;
1024 set_current_program_space (inf
->pspace
);
1026 inf
->symfile_flags
= SYMFILE_NO_READ
;
1027 clone_program_space (inf
->pspace
, vfork_parent
->pspace
);
1029 resume_parent
= vfork_parent
->pid
;
1032 gdb_assert (current_program_space
== inf
->pspace
);
1034 if (non_stop
&& resume_parent
!= -1)
1036 /* If the user wanted the parent to be running, let it go
1038 scoped_restore_current_thread restore_thread
;
1040 infrun_debug_printf ("resuming vfork parent process %d",
1043 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
1048 /* Enum strings for "set|show follow-exec-mode". */
1050 static const char follow_exec_mode_new
[] = "new";
1051 static const char follow_exec_mode_same
[] = "same";
1052 static const char *const follow_exec_mode_names
[] =
1054 follow_exec_mode_new
,
1055 follow_exec_mode_same
,
1059 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1061 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1062 struct cmd_list_element
*c
, const char *value
)
1064 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1067 /* EXEC_FILE_TARGET is assumed to be non-NULL. */
1070 follow_exec (ptid_t ptid
, const char *exec_file_target
)
1072 int pid
= ptid
.pid ();
1073 ptid_t process_ptid
;
1075 /* Switch terminal for any messages produced e.g. by
1076 breakpoint_re_set. */
1077 target_terminal::ours_for_output ();
1079 /* This is an exec event that we actually wish to pay attention to.
1080 Refresh our symbol table to the newly exec'd program, remove any
1081 momentary bp's, etc.
1083 If there are breakpoints, they aren't really inserted now,
1084 since the exec() transformed our inferior into a fresh set
1087 We want to preserve symbolic breakpoints on the list, since
1088 we have hopes that they can be reset after the new a.out's
1089 symbol table is read.
1091 However, any "raw" breakpoints must be removed from the list
1092 (e.g., the solib bp's), since their address is probably invalid
1095 And, we DON'T want to call delete_breakpoints() here, since
1096 that may write the bp's "shadow contents" (the instruction
1097 value that was overwritten with a TRAP instruction). Since
1098 we now have a new a.out, those shadow contents aren't valid. */
1100 mark_breakpoints_out ();
1102 /* The target reports the exec event to the main thread, even if
1103 some other thread does the exec, and even if the main thread was
1104 stopped or already gone. We may still have non-leader threads of
1105 the process on our list. E.g., on targets that don't have thread
1106 exit events (like remote); or on native Linux in non-stop mode if
1107 there were only two threads in the inferior and the non-leader
1108 one is the one that execs (and nothing forces an update of the
1109 thread list up to here). When debugging remotely, it's best to
1110 avoid extra traffic, when possible, so avoid syncing the thread
1111 list with the target, and instead go ahead and delete all threads
1112 of the process but one that reported the event. Note this must
1113 be done before calling update_breakpoints_after_exec, as
1114 otherwise clearing the threads' resources would reference stale
1115 thread breakpoints -- it may have been one of these threads that
1116 stepped across the exec. We could just clear their stepping
1117 states, but as long as we're iterating, might as well delete
1118 them. Deleting them now rather than at the next user-visible
1119 stop provides a nicer sequence of events for user and MI
1121 for (thread_info
*th
: all_threads_safe ())
1122 if (th
->ptid
.pid () == pid
&& th
->ptid
!= ptid
)
1125 /* We also need to clear any left over stale state for the
1126 leader/event thread. E.g., if there was any step-resume
1127 breakpoint or similar, it's gone now. We cannot truly
1128 step-to-next statement through an exec(). */
1129 thread_info
*th
= inferior_thread ();
1130 th
->control
.step_resume_breakpoint
= NULL
;
1131 th
->control
.exception_resume_breakpoint
= NULL
;
1132 th
->control
.single_step_breakpoints
= NULL
;
1133 th
->control
.step_range_start
= 0;
1134 th
->control
.step_range_end
= 0;
1136 /* The user may have had the main thread held stopped in the
1137 previous image (e.g., schedlock on, or non-stop). Release
1139 th
->stop_requested
= 0;
1141 update_breakpoints_after_exec ();
1143 /* What is this a.out's name? */
1144 process_ptid
= ptid_t (pid
);
1145 printf_unfiltered (_("%s is executing new program: %s\n"),
1146 target_pid_to_str (process_ptid
).c_str (),
1149 /* We've followed the inferior through an exec. Therefore, the
1150 inferior has essentially been killed & reborn. */
1152 breakpoint_init_inferior (inf_execd
);
1154 gdb::unique_xmalloc_ptr
<char> exec_file_host
1155 = exec_file_find (exec_file_target
, NULL
);
1157 /* If we were unable to map the executable target pathname onto a host
1158 pathname, tell the user that. Otherwise GDB's subsequent behavior
1159 is confusing. Maybe it would even be better to stop at this point
1160 so that the user can specify a file manually before continuing. */
1161 if (exec_file_host
== NULL
)
1162 warning (_("Could not load symbols for executable %s.\n"
1163 "Do you need \"set sysroot\"?"),
1166 /* Reset the shared library package. This ensures that we get a
1167 shlib event when the child reaches "_start", at which point the
1168 dld will have had a chance to initialize the child. */
1169 /* Also, loading a symbol file below may trigger symbol lookups, and
1170 we don't want those to be satisfied by the libraries of the
1171 previous incarnation of this process. */
1172 no_shared_libraries (NULL
, 0);
1174 struct inferior
*inf
= current_inferior ();
1176 if (follow_exec_mode_string
== follow_exec_mode_new
)
1178 /* The user wants to keep the old inferior and program spaces
1179 around. Create a new fresh one, and switch to it. */
1181 /* Do exit processing for the original inferior before setting the new
1182 inferior's pid. Having two inferiors with the same pid would confuse
1183 find_inferior_p(t)id. Transfer the terminal state and info from the
1184 old to the new inferior. */
1185 inferior
*new_inferior
= add_inferior_with_spaces ();
1187 swap_terminal_info (new_inferior
, inf
);
1188 exit_inferior_silent (inf
);
1190 new_inferior
->pid
= pid
;
1191 target_follow_exec (new_inferior
, ptid
, exec_file_target
);
1193 /* We continue with the new inferior. */
1198 /* The old description may no longer be fit for the new image.
1199 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1200 old description; we'll read a new one below. No need to do
1201 this on "follow-exec-mode new", as the old inferior stays
1202 around (its description is later cleared/refetched on
1204 target_clear_description ();
1205 target_follow_exec (inf
, ptid
, exec_file_target
);
1208 gdb_assert (current_inferior () == inf
);
1209 gdb_assert (current_program_space
== inf
->pspace
);
1211 /* Attempt to open the exec file. SYMFILE_DEFER_BP_RESET is used
1212 because the proper displacement for a PIE (Position Independent
1213 Executable) main symbol file will only be computed by
1214 solib_create_inferior_hook below. breakpoint_re_set would fail
1215 to insert the breakpoints with the zero displacement. */
1216 try_open_exec_file (exec_file_host
.get (), inf
, SYMFILE_DEFER_BP_RESET
);
1218 /* If the target can specify a description, read it. Must do this
1219 after flipping to the new executable (because the target supplied
1220 description must be compatible with the executable's
1221 architecture, and the old executable may e.g., be 32-bit, while
1222 the new one 64-bit), and before anything involving memory or
1224 target_find_description ();
1226 gdb::observers::inferior_execd
.notify (inf
);
1228 breakpoint_re_set ();
1230 /* Reinsert all breakpoints. (Those which were symbolic have
1231 been reset to the proper address in the new a.out, thanks
1232 to symbol_file_command...). */
1233 insert_breakpoints ();
1235 /* The next resume of this inferior should bring it to the shlib
1236 startup breakpoints. (If the user had also set bp's on
1237 "main" from the old (parent) process, then they'll auto-
1238 matically get reset there in the new process.). */
1241 /* The chain of threads that need to do a step-over operation to get
1242 past e.g., a breakpoint. What technique is used to step over the
1243 breakpoint/watchpoint does not matter -- all threads end up in the
1244 same queue, to maintain rough temporal order of execution, in order
1245 to avoid starvation, otherwise, we could e.g., find ourselves
1246 constantly stepping the same couple threads past their breakpoints
1247 over and over, if the single-step finish fast enough. */
1248 struct thread_info
*global_thread_step_over_chain_head
;
1250 /* Bit flags indicating what the thread needs to step over. */
1252 enum step_over_what_flag
1254 /* Step over a breakpoint. */
1255 STEP_OVER_BREAKPOINT
= 1,
1257 /* Step past a non-continuable watchpoint, in order to let the
1258 instruction execute so we can evaluate the watchpoint
1260 STEP_OVER_WATCHPOINT
= 2
1262 DEF_ENUM_FLAGS_TYPE (enum step_over_what_flag
, step_over_what
);
1264 /* Info about an instruction that is being stepped over. */
1266 struct step_over_info
1268 /* If we're stepping past a breakpoint, this is the address space
1269 and address of the instruction the breakpoint is set at. We'll
1270 skip inserting all breakpoints here. Valid iff ASPACE is
1272 const address_space
*aspace
= nullptr;
1273 CORE_ADDR address
= 0;
1275 /* The instruction being stepped over triggers a nonsteppable
1276 watchpoint. If true, we'll skip inserting watchpoints. */
1277 int nonsteppable_watchpoint_p
= 0;
1279 /* The thread's global number. */
1283 /* The step-over info of the location that is being stepped over.
1285 Note that with async/breakpoint always-inserted mode, a user might
1286 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1287 being stepped over. As setting a new breakpoint inserts all
1288 breakpoints, we need to make sure the breakpoint being stepped over
1289 isn't inserted then. We do that by only clearing the step-over
1290 info when the step-over is actually finished (or aborted).
1292 Presently GDB can only step over one breakpoint at any given time.
1293 Given threads that can't run code in the same address space as the
1294 breakpoint's can't really miss the breakpoint, GDB could be taught
1295 to step-over at most one breakpoint per address space (so this info
1296 could move to the address space object if/when GDB is extended).
1297 The set of breakpoints being stepped over will normally be much
1298 smaller than the set of all breakpoints, so a flag in the
1299 breakpoint location structure would be wasteful. A separate list
1300 also saves complexity and run-time, as otherwise we'd have to go
1301 through all breakpoint locations clearing their flag whenever we
1302 start a new sequence. Similar considerations weigh against storing
1303 this info in the thread object. Plus, not all step overs actually
1304 have breakpoint locations -- e.g., stepping past a single-step
1305 breakpoint, or stepping to complete a non-continuable
1307 static struct step_over_info step_over_info
;
1309 /* Record the address of the breakpoint/instruction we're currently
1311 N.B. We record the aspace and address now, instead of say just the thread,
1312 because when we need the info later the thread may be running. */
1315 set_step_over_info (const address_space
*aspace
, CORE_ADDR address
,
1316 int nonsteppable_watchpoint_p
,
1319 step_over_info
.aspace
= aspace
;
1320 step_over_info
.address
= address
;
1321 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1322 step_over_info
.thread
= thread
;
1325 /* Called when we're not longer stepping over a breakpoint / an
1326 instruction, so all breakpoints are free to be (re)inserted. */
1329 clear_step_over_info (void)
1331 infrun_debug_printf ("clearing step over info");
1332 step_over_info
.aspace
= NULL
;
1333 step_over_info
.address
= 0;
1334 step_over_info
.nonsteppable_watchpoint_p
= 0;
1335 step_over_info
.thread
= -1;
1341 stepping_past_instruction_at (struct address_space
*aspace
,
1344 return (step_over_info
.aspace
!= NULL
1345 && breakpoint_address_match (aspace
, address
,
1346 step_over_info
.aspace
,
1347 step_over_info
.address
));
1353 thread_is_stepping_over_breakpoint (int thread
)
1355 return (step_over_info
.thread
!= -1
1356 && thread
== step_over_info
.thread
);
1362 stepping_past_nonsteppable_watchpoint (void)
1364 return step_over_info
.nonsteppable_watchpoint_p
;
1367 /* Returns true if step-over info is valid. */
1370 step_over_info_valid_p (void)
1372 return (step_over_info
.aspace
!= NULL
1373 || stepping_past_nonsteppable_watchpoint ());
1377 /* Displaced stepping. */
1379 /* In non-stop debugging mode, we must take special care to manage
1380 breakpoints properly; in particular, the traditional strategy for
1381 stepping a thread past a breakpoint it has hit is unsuitable.
1382 'Displaced stepping' is a tactic for stepping one thread past a
1383 breakpoint it has hit while ensuring that other threads running
1384 concurrently will hit the breakpoint as they should.
1386 The traditional way to step a thread T off a breakpoint in a
1387 multi-threaded program in all-stop mode is as follows:
1389 a0) Initially, all threads are stopped, and breakpoints are not
1391 a1) We single-step T, leaving breakpoints uninserted.
1392 a2) We insert breakpoints, and resume all threads.
1394 In non-stop debugging, however, this strategy is unsuitable: we
1395 don't want to have to stop all threads in the system in order to
1396 continue or step T past a breakpoint. Instead, we use displaced
1399 n0) Initially, T is stopped, other threads are running, and
1400 breakpoints are inserted.
1401 n1) We copy the instruction "under" the breakpoint to a separate
1402 location, outside the main code stream, making any adjustments
1403 to the instruction, register, and memory state as directed by
1405 n2) We single-step T over the instruction at its new location.
1406 n3) We adjust the resulting register and memory state as directed
1407 by T's architecture. This includes resetting T's PC to point
1408 back into the main instruction stream.
1411 This approach depends on the following gdbarch methods:
1413 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1414 indicate where to copy the instruction, and how much space must
1415 be reserved there. We use these in step n1.
1417 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1418 address, and makes any necessary adjustments to the instruction,
1419 register contents, and memory. We use this in step n1.
1421 - gdbarch_displaced_step_fixup adjusts registers and memory after
1422 we have successfully single-stepped the instruction, to yield the
1423 same effect the instruction would have had if we had executed it
1424 at its original address. We use this in step n3.
1426 The gdbarch_displaced_step_copy_insn and
1427 gdbarch_displaced_step_fixup functions must be written so that
1428 copying an instruction with gdbarch_displaced_step_copy_insn,
1429 single-stepping across the copied instruction, and then applying
1430 gdbarch_displaced_insn_fixup should have the same effects on the
1431 thread's memory and registers as stepping the instruction in place
1432 would have. Exactly which responsibilities fall to the copy and
1433 which fall to the fixup is up to the author of those functions.
1435 See the comments in gdbarch.sh for details.
1437 Note that displaced stepping and software single-step cannot
1438 currently be used in combination, although with some care I think
1439 they could be made to. Software single-step works by placing
1440 breakpoints on all possible subsequent instructions; if the
1441 displaced instruction is a PC-relative jump, those breakpoints
1442 could fall in very strange places --- on pages that aren't
1443 executable, or at addresses that are not proper instruction
1444 boundaries. (We do generally let other threads run while we wait
1445 to hit the software single-step breakpoint, and they might
1446 encounter such a corrupted instruction.) One way to work around
1447 this would be to have gdbarch_displaced_step_copy_insn fully
1448 simulate the effect of PC-relative instructions (and return NULL)
1449 on architectures that use software single-stepping.
1451 In non-stop mode, we can have independent and simultaneous step
1452 requests, so more than one thread may need to simultaneously step
1453 over a breakpoint. The current implementation assumes there is
1454 only one scratch space per process. In this case, we have to
1455 serialize access to the scratch space. If thread A wants to step
1456 over a breakpoint, but we are currently waiting for some other
1457 thread to complete a displaced step, we leave thread A stopped and
1458 place it in the displaced_step_request_queue. Whenever a displaced
1459 step finishes, we pick the next thread in the queue and start a new
1460 displaced step operation on it. See displaced_step_prepare and
1461 displaced_step_finish for details. */
1463 /* Return true if THREAD is doing a displaced step. */
1466 displaced_step_in_progress_thread (thread_info
*thread
)
1468 gdb_assert (thread
!= NULL
);
1470 return thread
->displaced_step_state
.in_progress ();
1473 /* Return true if INF has a thread doing a displaced step. */
1476 displaced_step_in_progress (inferior
*inf
)
1478 return inf
->displaced_step_state
.in_progress_count
> 0;
1481 /* Return true if any thread is doing a displaced step. */
1484 displaced_step_in_progress_any_thread ()
1486 for (inferior
*inf
: all_non_exited_inferiors ())
1488 if (displaced_step_in_progress (inf
))
1496 infrun_inferior_exit (struct inferior
*inf
)
1498 inf
->displaced_step_state
.reset ();
1502 infrun_inferior_execd (inferior
*inf
)
1504 /* If some threads where was doing a displaced step in this inferior at the
1505 moment of the exec, they no longer exist. Even if the exec'ing thread
1506 doing a displaced step, we don't want to to any fixup nor restore displaced
1507 stepping buffer bytes. */
1508 inf
->displaced_step_state
.reset ();
1510 for (thread_info
*thread
: inf
->threads ())
1511 thread
->displaced_step_state
.reset ();
1513 /* Since an in-line step is done with everything else stopped, if there was
1514 one in progress at the time of the exec, it must have been the exec'ing
1516 clear_step_over_info ();
1519 /* If ON, and the architecture supports it, GDB will use displaced
1520 stepping to step over breakpoints. If OFF, or if the architecture
1521 doesn't support it, GDB will instead use the traditional
1522 hold-and-step approach. If AUTO (which is the default), GDB will
1523 decide which technique to use to step over breakpoints depending on
1524 whether the target works in a non-stop way (see use_displaced_stepping). */
1526 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1529 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1530 struct cmd_list_element
*c
,
1533 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1534 fprintf_filtered (file
,
1535 _("Debugger's willingness to use displaced stepping "
1536 "to step over breakpoints is %s (currently %s).\n"),
1537 value
, target_is_non_stop_p () ? "on" : "off");
1539 fprintf_filtered (file
,
1540 _("Debugger's willingness to use displaced stepping "
1541 "to step over breakpoints is %s.\n"), value
);
1544 /* Return true if the gdbarch implements the required methods to use
1545 displaced stepping. */
1548 gdbarch_supports_displaced_stepping (gdbarch
*arch
)
1550 /* Only check for the presence of `prepare`. The gdbarch verification ensures
1551 that if `prepare` is provided, so is `finish`. */
1552 return gdbarch_displaced_step_prepare_p (arch
);
1555 /* Return non-zero if displaced stepping can/should be used to step
1556 over breakpoints of thread TP. */
1559 use_displaced_stepping (thread_info
*tp
)
1561 /* If the user disabled it explicitly, don't use displaced stepping. */
1562 if (can_use_displaced_stepping
== AUTO_BOOLEAN_FALSE
)
1565 /* If "auto", only use displaced stepping if the target operates in a non-stop
1567 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
1568 && !target_is_non_stop_p ())
1571 gdbarch
*gdbarch
= get_thread_regcache (tp
)->arch ();
1573 /* If the architecture doesn't implement displaced stepping, don't use
1575 if (!gdbarch_supports_displaced_stepping (gdbarch
))
1578 /* If recording, don't use displaced stepping. */
1579 if (find_record_target () != nullptr)
1582 /* If displaced stepping failed before for this inferior, don't bother trying
1584 if (tp
->inf
->displaced_step_state
.failed_before
)
1590 /* Simple function wrapper around displaced_step_thread_state::reset. */
1593 displaced_step_reset (displaced_step_thread_state
*displaced
)
1595 displaced
->reset ();
1598 /* A cleanup that wraps displaced_step_reset. We use this instead of, say,
1599 SCOPE_EXIT, because it needs to be discardable with "cleanup.release ()". */
1601 using displaced_step_reset_cleanup
= FORWARD_SCOPE_EXIT (displaced_step_reset
);
1606 displaced_step_dump_bytes (const gdb_byte
*buf
, size_t len
)
1610 for (size_t i
= 0; i
< len
; i
++)
1613 ret
+= string_printf ("%02x", buf
[i
]);
1615 ret
+= string_printf (" %02x", buf
[i
]);
1621 /* Prepare to single-step, using displaced stepping.
1623 Note that we cannot use displaced stepping when we have a signal to
1624 deliver. If we have a signal to deliver and an instruction to step
1625 over, then after the step, there will be no indication from the
1626 target whether the thread entered a signal handler or ignored the
1627 signal and stepped over the instruction successfully --- both cases
1628 result in a simple SIGTRAP. In the first case we mustn't do a
1629 fixup, and in the second case we must --- but we can't tell which.
1630 Comments in the code for 'random signals' in handle_inferior_event
1631 explain how we handle this case instead.
1633 Returns DISPLACED_STEP_PREPARE_STATUS_OK if preparing was successful -- this
1634 thread is going to be stepped now; DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE
1635 if displaced stepping this thread got queued; or
1636 DISPLACED_STEP_PREPARE_STATUS_CANT if this instruction can't be displaced
1639 static displaced_step_prepare_status
1640 displaced_step_prepare_throw (thread_info
*tp
)
1642 regcache
*regcache
= get_thread_regcache (tp
);
1643 struct gdbarch
*gdbarch
= regcache
->arch ();
1644 displaced_step_thread_state
&disp_step_thread_state
1645 = tp
->displaced_step_state
;
1647 /* We should never reach this function if the architecture does not
1648 support displaced stepping. */
1649 gdb_assert (gdbarch_supports_displaced_stepping (gdbarch
));
1651 /* Nor if the thread isn't meant to step over a breakpoint. */
1652 gdb_assert (tp
->control
.trap_expected
);
1654 /* Disable range stepping while executing in the scratch pad. We
1655 want a single-step even if executing the displaced instruction in
1656 the scratch buffer lands within the stepping range (e.g., a
1658 tp
->control
.may_range_step
= 0;
1660 /* We are about to start a displaced step for this thread. If one is already
1661 in progress, something's wrong. */
1662 gdb_assert (!disp_step_thread_state
.in_progress ());
1664 if (tp
->inf
->displaced_step_state
.unavailable
)
1666 /* The gdbarch tells us it's not worth asking to try a prepare because
1667 it is likely that it will return unavailable, so don't bother asking. */
1669 displaced_debug_printf ("deferring step of %s",
1670 target_pid_to_str (tp
->ptid
).c_str ());
1672 global_thread_step_over_chain_enqueue (tp
);
1673 return DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE
;
1676 displaced_debug_printf ("displaced-stepping %s now",
1677 target_pid_to_str (tp
->ptid
).c_str ());
1679 scoped_restore_current_thread restore_thread
;
1681 switch_to_thread (tp
);
1683 CORE_ADDR original_pc
= regcache_read_pc (regcache
);
1684 CORE_ADDR displaced_pc
;
1686 displaced_step_prepare_status status
1687 = gdbarch_displaced_step_prepare (gdbarch
, tp
, displaced_pc
);
1689 if (status
== DISPLACED_STEP_PREPARE_STATUS_CANT
)
1691 displaced_debug_printf ("failed to prepare (%s)",
1692 target_pid_to_str (tp
->ptid
).c_str ());
1694 return DISPLACED_STEP_PREPARE_STATUS_CANT
;
1696 else if (status
== DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE
)
1698 /* Not enough displaced stepping resources available, defer this
1699 request by placing it the queue. */
1701 displaced_debug_printf ("not enough resources available, "
1702 "deferring step of %s",
1703 target_pid_to_str (tp
->ptid
).c_str ());
1705 global_thread_step_over_chain_enqueue (tp
);
1707 return DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE
;
1710 gdb_assert (status
== DISPLACED_STEP_PREPARE_STATUS_OK
);
1712 /* Save the information we need to fix things up if the step
1714 disp_step_thread_state
.set (gdbarch
);
1716 tp
->inf
->displaced_step_state
.in_progress_count
++;
1718 displaced_debug_printf ("prepared successfully thread=%s, "
1719 "original_pc=%s, displaced_pc=%s",
1720 target_pid_to_str (tp
->ptid
).c_str (),
1721 paddress (gdbarch
, original_pc
),
1722 paddress (gdbarch
, displaced_pc
));
1724 return DISPLACED_STEP_PREPARE_STATUS_OK
;
1727 /* Wrapper for displaced_step_prepare_throw that disabled further
1728 attempts at displaced stepping if we get a memory error. */
1730 static displaced_step_prepare_status
1731 displaced_step_prepare (thread_info
*thread
)
1733 displaced_step_prepare_status status
1734 = DISPLACED_STEP_PREPARE_STATUS_CANT
;
1738 status
= displaced_step_prepare_throw (thread
);
1740 catch (const gdb_exception_error
&ex
)
1742 if (ex
.error
!= MEMORY_ERROR
1743 && ex
.error
!= NOT_SUPPORTED_ERROR
)
1746 infrun_debug_printf ("caught exception, disabling displaced stepping: %s",
1749 /* Be verbose if "set displaced-stepping" is "on", silent if
1751 if (can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1753 warning (_("disabling displaced stepping: %s"),
1757 /* Disable further displaced stepping attempts. */
1758 thread
->inf
->displaced_step_state
.failed_before
= 1;
1764 /* If we displaced stepped an instruction successfully, adjust registers and
1765 memory to yield the same effect the instruction would have had if we had
1766 executed it at its original address, and return
1767 DISPLACED_STEP_FINISH_STATUS_OK. If the instruction didn't complete,
1768 relocate the PC and return DISPLACED_STEP_FINISH_STATUS_NOT_EXECUTED.
1770 If the thread wasn't displaced stepping, return
1771 DISPLACED_STEP_FINISH_STATUS_OK as well. */
1773 static displaced_step_finish_status
1774 displaced_step_finish (thread_info
*event_thread
, enum gdb_signal signal
)
1776 displaced_step_thread_state
*displaced
= &event_thread
->displaced_step_state
;
1778 /* Was this thread performing a displaced step? */
1779 if (!displaced
->in_progress ())
1780 return DISPLACED_STEP_FINISH_STATUS_OK
;
1782 gdb_assert (event_thread
->inf
->displaced_step_state
.in_progress_count
> 0);
1783 event_thread
->inf
->displaced_step_state
.in_progress_count
--;
1785 /* Fixup may need to read memory/registers. Switch to the thread
1786 that we're fixing up. Also, target_stopped_by_watchpoint checks
1787 the current thread, and displaced_step_restore performs ptid-dependent
1788 memory accesses using current_inferior(). */
1789 switch_to_thread (event_thread
);
1791 displaced_step_reset_cleanup
cleanup (displaced
);
1793 /* Do the fixup, and release the resources acquired to do the displaced
1795 return gdbarch_displaced_step_finish (displaced
->get_original_gdbarch (),
1796 event_thread
, signal
);
1799 /* Data to be passed around while handling an event. This data is
1800 discarded between events. */
1801 struct execution_control_state
1803 process_stratum_target
*target
;
1805 /* The thread that got the event, if this was a thread event; NULL
1807 struct thread_info
*event_thread
;
1809 struct target_waitstatus ws
;
1810 int stop_func_filled_in
;
1811 CORE_ADDR stop_func_start
;
1812 CORE_ADDR stop_func_end
;
1813 const char *stop_func_name
;
1816 /* True if the event thread hit the single-step breakpoint of
1817 another thread. Thus the event doesn't cause a stop, the thread
1818 needs to be single-stepped past the single-step breakpoint before
1819 we can switch back to the original stepping thread. */
1820 int hit_singlestep_breakpoint
;
1823 /* Clear ECS and set it to point at TP. */
1826 reset_ecs (struct execution_control_state
*ecs
, struct thread_info
*tp
)
1828 memset (ecs
, 0, sizeof (*ecs
));
1829 ecs
->event_thread
= tp
;
1830 ecs
->ptid
= tp
->ptid
;
1833 static void keep_going_pass_signal (struct execution_control_state
*ecs
);
1834 static void prepare_to_wait (struct execution_control_state
*ecs
);
1835 static bool keep_going_stepped_thread (struct thread_info
*tp
);
1836 static step_over_what
thread_still_needs_step_over (struct thread_info
*tp
);
1838 /* Are there any pending step-over requests? If so, run all we can
1839 now and return true. Otherwise, return false. */
1842 start_step_over (void)
1844 INFRUN_SCOPED_DEBUG_ENTER_EXIT
;
1848 /* Don't start a new step-over if we already have an in-line
1849 step-over operation ongoing. */
1850 if (step_over_info_valid_p ())
1853 /* Steal the global thread step over chain. As we try to initiate displaced
1854 steps, threads will be enqueued in the global chain if no buffers are
1855 available. If we iterated on the global chain directly, we might iterate
1857 thread_info
*threads_to_step
= global_thread_step_over_chain_head
;
1858 global_thread_step_over_chain_head
= NULL
;
1860 infrun_debug_printf ("stealing global queue of threads to step, length = %d",
1861 thread_step_over_chain_length (threads_to_step
));
1863 bool started
= false;
1865 /* On scope exit (whatever the reason, return or exception), if there are
1866 threads left in the THREADS_TO_STEP chain, put back these threads in the
1870 if (threads_to_step
== nullptr)
1871 infrun_debug_printf ("step-over queue now empty");
1874 infrun_debug_printf ("putting back %d threads to step in global queue",
1875 thread_step_over_chain_length (threads_to_step
));
1877 global_thread_step_over_chain_enqueue_chain (threads_to_step
);
1881 for (thread_info
*tp
= threads_to_step
; tp
!= NULL
; tp
= next
)
1883 struct execution_control_state ecss
;
1884 struct execution_control_state
*ecs
= &ecss
;
1885 step_over_what step_what
;
1886 int must_be_in_line
;
1888 gdb_assert (!tp
->stop_requested
);
1890 next
= thread_step_over_chain_next (threads_to_step
, tp
);
1892 if (tp
->inf
->displaced_step_state
.unavailable
)
1894 /* The arch told us to not even try preparing another displaced step
1895 for this inferior. Just leave the thread in THREADS_TO_STEP, it
1896 will get moved to the global chain on scope exit. */
1900 /* Remove thread from the THREADS_TO_STEP chain. If anything goes wrong
1901 while we try to prepare the displaced step, we don't add it back to
1902 the global step over chain. This is to avoid a thread staying in the
1903 step over chain indefinitely if something goes wrong when resuming it
1904 If the error is intermittent and it still needs a step over, it will
1905 get enqueued again when we try to resume it normally. */
1906 thread_step_over_chain_remove (&threads_to_step
, tp
);
1908 step_what
= thread_still_needs_step_over (tp
);
1909 must_be_in_line
= ((step_what
& STEP_OVER_WATCHPOINT
)
1910 || ((step_what
& STEP_OVER_BREAKPOINT
)
1911 && !use_displaced_stepping (tp
)));
1913 /* We currently stop all threads of all processes to step-over
1914 in-line. If we need to start a new in-line step-over, let
1915 any pending displaced steps finish first. */
1916 if (must_be_in_line
&& displaced_step_in_progress_any_thread ())
1918 global_thread_step_over_chain_enqueue (tp
);
1922 if (tp
->control
.trap_expected
1926 internal_error (__FILE__
, __LINE__
,
1927 "[%s] has inconsistent state: "
1928 "trap_expected=%d, resumed=%d, executing=%d\n",
1929 target_pid_to_str (tp
->ptid
).c_str (),
1930 tp
->control
.trap_expected
,
1935 infrun_debug_printf ("resuming [%s] for step-over",
1936 target_pid_to_str (tp
->ptid
).c_str ());
1938 /* keep_going_pass_signal skips the step-over if the breakpoint
1939 is no longer inserted. In all-stop, we want to keep looking
1940 for a thread that needs a step-over instead of resuming TP,
1941 because we wouldn't be able to resume anything else until the
1942 target stops again. In non-stop, the resume always resumes
1943 only TP, so it's OK to let the thread resume freely. */
1944 if (!target_is_non_stop_p () && !step_what
)
1947 switch_to_thread (tp
);
1948 reset_ecs (ecs
, tp
);
1949 keep_going_pass_signal (ecs
);
1951 if (!ecs
->wait_some_more
)
1952 error (_("Command aborted."));
1954 /* If the thread's step over could not be initiated because no buffers
1955 were available, it was re-added to the global step over chain. */
1958 infrun_debug_printf ("[%s] was resumed.",
1959 target_pid_to_str (tp
->ptid
).c_str ());
1960 gdb_assert (!thread_is_in_step_over_chain (tp
));
1964 infrun_debug_printf ("[%s] was NOT resumed.",
1965 target_pid_to_str (tp
->ptid
).c_str ());
1966 gdb_assert (thread_is_in_step_over_chain (tp
));
1969 /* If we started a new in-line step-over, we're done. */
1970 if (step_over_info_valid_p ())
1972 gdb_assert (tp
->control
.trap_expected
);
1977 if (!target_is_non_stop_p ())
1979 /* On all-stop, shouldn't have resumed unless we needed a
1981 gdb_assert (tp
->control
.trap_expected
1982 || tp
->step_after_step_resume_breakpoint
);
1984 /* With remote targets (at least), in all-stop, we can't
1985 issue any further remote commands until the program stops
1991 /* Either the thread no longer needed a step-over, or a new
1992 displaced stepping sequence started. Even in the latter
1993 case, continue looking. Maybe we can also start another
1994 displaced step on a thread of other process. */
2000 /* Update global variables holding ptids to hold NEW_PTID if they were
2001 holding OLD_PTID. */
2003 infrun_thread_ptid_changed (process_stratum_target
*target
,
2004 ptid_t old_ptid
, ptid_t new_ptid
)
2006 if (inferior_ptid
== old_ptid
2007 && current_inferior ()->process_target () == target
)
2008 inferior_ptid
= new_ptid
;
2013 static const char schedlock_off
[] = "off";
2014 static const char schedlock_on
[] = "on";
2015 static const char schedlock_step
[] = "step";
2016 static const char schedlock_replay
[] = "replay";
2017 static const char *const scheduler_enums
[] = {
2024 static const char *scheduler_mode
= schedlock_replay
;
2026 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
2027 struct cmd_list_element
*c
, const char *value
)
2029 fprintf_filtered (file
,
2030 _("Mode for locking scheduler "
2031 "during execution is \"%s\".\n"),
2036 set_schedlock_func (const char *args
, int from_tty
, struct cmd_list_element
*c
)
2038 if (!target_can_lock_scheduler ())
2040 scheduler_mode
= schedlock_off
;
2041 error (_("Target '%s' cannot support this command."),
2042 target_shortname ());
2046 /* True if execution commands resume all threads of all processes by
2047 default; otherwise, resume only threads of the current inferior
2049 bool sched_multi
= false;
2051 /* Try to setup for software single stepping. Return true if target_resume()
2052 should use hardware single step.
2054 GDBARCH the current gdbarch. */
2057 maybe_software_singlestep (struct gdbarch
*gdbarch
)
2059 bool hw_step
= true;
2061 if (execution_direction
== EXEC_FORWARD
2062 && gdbarch_software_single_step_p (gdbarch
))
2063 hw_step
= !insert_single_step_breakpoints (gdbarch
);
2071 user_visible_resume_ptid (int step
)
2077 /* With non-stop mode on, threads are always handled
2079 resume_ptid
= inferior_ptid
;
2081 else if ((scheduler_mode
== schedlock_on
)
2082 || (scheduler_mode
== schedlock_step
&& step
))
2084 /* User-settable 'scheduler' mode requires solo thread
2086 resume_ptid
= inferior_ptid
;
2088 else if ((scheduler_mode
== schedlock_replay
)
2089 && target_record_will_replay (minus_one_ptid
, execution_direction
))
2091 /* User-settable 'scheduler' mode requires solo thread resume in replay
2093 resume_ptid
= inferior_ptid
;
2095 else if (!sched_multi
&& target_supports_multi_process ())
2097 /* Resume all threads of the current process (and none of other
2099 resume_ptid
= ptid_t (inferior_ptid
.pid ());
2103 /* Resume all threads of all processes. */
2104 resume_ptid
= RESUME_ALL
;
2112 process_stratum_target
*
2113 user_visible_resume_target (ptid_t resume_ptid
)
2115 return (resume_ptid
== minus_one_ptid
&& sched_multi
2117 : current_inferior ()->process_target ());
2120 /* Return a ptid representing the set of threads that we will resume,
2121 in the perspective of the target, assuming run control handling
2122 does not require leaving some threads stopped (e.g., stepping past
2123 breakpoint). USER_STEP indicates whether we're about to start the
2124 target for a stepping command. */
2127 internal_resume_ptid (int user_step
)
2129 /* In non-stop, we always control threads individually. Note that
2130 the target may always work in non-stop mode even with "set
2131 non-stop off", in which case user_visible_resume_ptid could
2132 return a wildcard ptid. */
2133 if (target_is_non_stop_p ())
2134 return inferior_ptid
;
2136 return user_visible_resume_ptid (user_step
);
2139 /* Wrapper for target_resume, that handles infrun-specific
2143 do_target_resume (ptid_t resume_ptid
, bool step
, enum gdb_signal sig
)
2145 struct thread_info
*tp
= inferior_thread ();
2147 gdb_assert (!tp
->stop_requested
);
2149 /* Install inferior's terminal modes. */
2150 target_terminal::inferior ();
2152 /* Avoid confusing the next resume, if the next stop/resume
2153 happens to apply to another thread. */
2154 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2156 /* Advise target which signals may be handled silently.
2158 If we have removed breakpoints because we are stepping over one
2159 in-line (in any thread), we need to receive all signals to avoid
2160 accidentally skipping a breakpoint during execution of a signal
2163 Likewise if we're displaced stepping, otherwise a trap for a
2164 breakpoint in a signal handler might be confused with the
2165 displaced step finishing. We don't make the displaced_step_finish
2166 step distinguish the cases instead, because:
2168 - a backtrace while stopped in the signal handler would show the
2169 scratch pad as frame older than the signal handler, instead of
2170 the real mainline code.
2172 - when the thread is later resumed, the signal handler would
2173 return to the scratch pad area, which would no longer be
2175 if (step_over_info_valid_p ()
2176 || displaced_step_in_progress (tp
->inf
))
2177 target_pass_signals ({});
2179 target_pass_signals (signal_pass
);
2181 target_resume (resume_ptid
, step
, sig
);
2183 if (target_can_async_p ())
2187 /* Resume the inferior. SIG is the signal to give the inferior
2188 (GDB_SIGNAL_0 for none). Note: don't call this directly; instead
2189 call 'resume', which handles exceptions. */
2192 resume_1 (enum gdb_signal sig
)
2194 struct regcache
*regcache
= get_current_regcache ();
2195 struct gdbarch
*gdbarch
= regcache
->arch ();
2196 struct thread_info
*tp
= inferior_thread ();
2197 const address_space
*aspace
= regcache
->aspace ();
2199 /* This represents the user's step vs continue request. When
2200 deciding whether "set scheduler-locking step" applies, it's the
2201 user's intention that counts. */
2202 const int user_step
= tp
->control
.stepping_command
;
2203 /* This represents what we'll actually request the target to do.
2204 This can decay from a step to a continue, if e.g., we need to
2205 implement single-stepping with breakpoints (software
2209 gdb_assert (!tp
->stop_requested
);
2210 gdb_assert (!thread_is_in_step_over_chain (tp
));
2212 if (tp
->suspend
.waitstatus_pending_p
)
2215 ("thread %s has pending wait "
2216 "status %s (currently_stepping=%d).",
2217 target_pid_to_str (tp
->ptid
).c_str (),
2218 target_waitstatus_to_string (&tp
->suspend
.waitstatus
).c_str (),
2219 currently_stepping (tp
));
2221 tp
->inf
->process_target ()->threads_executing
= true;
2224 /* FIXME: What should we do if we are supposed to resume this
2225 thread with a signal? Maybe we should maintain a queue of
2226 pending signals to deliver. */
2227 if (sig
!= GDB_SIGNAL_0
)
2229 warning (_("Couldn't deliver signal %s to %s."),
2230 gdb_signal_to_name (sig
),
2231 target_pid_to_str (tp
->ptid
).c_str ());
2234 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2236 if (target_can_async_p ())
2239 /* Tell the event loop we have an event to process. */
2240 mark_async_event_handler (infrun_async_inferior_event_token
);
2245 tp
->stepped_breakpoint
= 0;
2247 /* Depends on stepped_breakpoint. */
2248 step
= currently_stepping (tp
);
2250 if (current_inferior ()->waiting_for_vfork_done
)
2252 /* Don't try to single-step a vfork parent that is waiting for
2253 the child to get out of the shared memory region (by exec'ing
2254 or exiting). This is particularly important on software
2255 single-step archs, as the child process would trip on the
2256 software single step breakpoint inserted for the parent
2257 process. Since the parent will not actually execute any
2258 instruction until the child is out of the shared region (such
2259 are vfork's semantics), it is safe to simply continue it.
2260 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2261 the parent, and tell it to `keep_going', which automatically
2262 re-sets it stepping. */
2263 infrun_debug_printf ("resume : clear step");
2267 CORE_ADDR pc
= regcache_read_pc (regcache
);
2269 infrun_debug_printf ("step=%d, signal=%s, trap_expected=%d, "
2270 "current thread [%s] at %s",
2271 step
, gdb_signal_to_symbol_string (sig
),
2272 tp
->control
.trap_expected
,
2273 target_pid_to_str (inferior_ptid
).c_str (),
2274 paddress (gdbarch
, pc
));
2276 /* Normally, by the time we reach `resume', the breakpoints are either
2277 removed or inserted, as appropriate. The exception is if we're sitting
2278 at a permanent breakpoint; we need to step over it, but permanent
2279 breakpoints can't be removed. So we have to test for it here. */
2280 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2282 if (sig
!= GDB_SIGNAL_0
)
2284 /* We have a signal to pass to the inferior. The resume
2285 may, or may not take us to the signal handler. If this
2286 is a step, we'll need to stop in the signal handler, if
2287 there's one, (if the target supports stepping into
2288 handlers), or in the next mainline instruction, if
2289 there's no handler. If this is a continue, we need to be
2290 sure to run the handler with all breakpoints inserted.
2291 In all cases, set a breakpoint at the current address
2292 (where the handler returns to), and once that breakpoint
2293 is hit, resume skipping the permanent breakpoint. If
2294 that breakpoint isn't hit, then we've stepped into the
2295 signal handler (or hit some other event). We'll delete
2296 the step-resume breakpoint then. */
2298 infrun_debug_printf ("resume: skipping permanent breakpoint, "
2299 "deliver signal first");
2301 clear_step_over_info ();
2302 tp
->control
.trap_expected
= 0;
2304 if (tp
->control
.step_resume_breakpoint
== NULL
)
2306 /* Set a "high-priority" step-resume, as we don't want
2307 user breakpoints at PC to trigger (again) when this
2309 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2310 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2312 tp
->step_after_step_resume_breakpoint
= step
;
2315 insert_breakpoints ();
2319 /* There's no signal to pass, we can go ahead and skip the
2320 permanent breakpoint manually. */
2321 infrun_debug_printf ("skipping permanent breakpoint");
2322 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2323 /* Update pc to reflect the new address from which we will
2324 execute instructions. */
2325 pc
= regcache_read_pc (regcache
);
2329 /* We've already advanced the PC, so the stepping part
2330 is done. Now we need to arrange for a trap to be
2331 reported to handle_inferior_event. Set a breakpoint
2332 at the current PC, and run to it. Don't update
2333 prev_pc, because if we end in
2334 switch_back_to_stepped_thread, we want the "expected
2335 thread advanced also" branch to be taken. IOW, we
2336 don't want this thread to step further from PC
2338 gdb_assert (!step_over_info_valid_p ());
2339 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2340 insert_breakpoints ();
2342 resume_ptid
= internal_resume_ptid (user_step
);
2343 do_target_resume (resume_ptid
, false, GDB_SIGNAL_0
);
2350 /* If we have a breakpoint to step over, make sure to do a single
2351 step only. Same if we have software watchpoints. */
2352 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2353 tp
->control
.may_range_step
= 0;
2355 /* If displaced stepping is enabled, step over breakpoints by executing a
2356 copy of the instruction at a different address.
2358 We can't use displaced stepping when we have a signal to deliver;
2359 the comments for displaced_step_prepare explain why. The
2360 comments in the handle_inferior event for dealing with 'random
2361 signals' explain what we do instead.
2363 We can't use displaced stepping when we are waiting for vfork_done
2364 event, displaced stepping breaks the vfork child similarly as single
2365 step software breakpoint. */
2366 if (tp
->control
.trap_expected
2367 && use_displaced_stepping (tp
)
2368 && !step_over_info_valid_p ()
2369 && sig
== GDB_SIGNAL_0
2370 && !current_inferior ()->waiting_for_vfork_done
)
2372 displaced_step_prepare_status prepare_status
2373 = displaced_step_prepare (tp
);
2375 if (prepare_status
== DISPLACED_STEP_PREPARE_STATUS_UNAVAILABLE
)
2377 infrun_debug_printf ("Got placed in step-over queue");
2379 tp
->control
.trap_expected
= 0;
2382 else if (prepare_status
== DISPLACED_STEP_PREPARE_STATUS_CANT
)
2384 /* Fallback to stepping over the breakpoint in-line. */
2386 if (target_is_non_stop_p ())
2387 stop_all_threads ();
2389 set_step_over_info (regcache
->aspace (),
2390 regcache_read_pc (regcache
), 0, tp
->global_num
);
2392 step
= maybe_software_singlestep (gdbarch
);
2394 insert_breakpoints ();
2396 else if (prepare_status
== DISPLACED_STEP_PREPARE_STATUS_OK
)
2398 /* Update pc to reflect the new address from which we will
2399 execute instructions due to displaced stepping. */
2400 pc
= regcache_read_pc (get_thread_regcache (tp
));
2402 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
);
2405 gdb_assert_not_reached (_("Invalid displaced_step_prepare_status "
2409 /* Do we need to do it the hard way, w/temp breakpoints? */
2411 step
= maybe_software_singlestep (gdbarch
);
2413 /* Currently, our software single-step implementation leads to different
2414 results than hardware single-stepping in one situation: when stepping
2415 into delivering a signal which has an associated signal handler,
2416 hardware single-step will stop at the first instruction of the handler,
2417 while software single-step will simply skip execution of the handler.
2419 For now, this difference in behavior is accepted since there is no
2420 easy way to actually implement single-stepping into a signal handler
2421 without kernel support.
2423 However, there is one scenario where this difference leads to follow-on
2424 problems: if we're stepping off a breakpoint by removing all breakpoints
2425 and then single-stepping. In this case, the software single-step
2426 behavior means that even if there is a *breakpoint* in the signal
2427 handler, GDB still would not stop.
2429 Fortunately, we can at least fix this particular issue. We detect
2430 here the case where we are about to deliver a signal while software
2431 single-stepping with breakpoints removed. In this situation, we
2432 revert the decisions to remove all breakpoints and insert single-
2433 step breakpoints, and instead we install a step-resume breakpoint
2434 at the current address, deliver the signal without stepping, and
2435 once we arrive back at the step-resume breakpoint, actually step
2436 over the breakpoint we originally wanted to step over. */
2437 if (thread_has_single_step_breakpoints_set (tp
)
2438 && sig
!= GDB_SIGNAL_0
2439 && step_over_info_valid_p ())
2441 /* If we have nested signals or a pending signal is delivered
2442 immediately after a handler returns, might already have
2443 a step-resume breakpoint set on the earlier handler. We cannot
2444 set another step-resume breakpoint; just continue on until the
2445 original breakpoint is hit. */
2446 if (tp
->control
.step_resume_breakpoint
== NULL
)
2448 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2449 tp
->step_after_step_resume_breakpoint
= 1;
2452 delete_single_step_breakpoints (tp
);
2454 clear_step_over_info ();
2455 tp
->control
.trap_expected
= 0;
2457 insert_breakpoints ();
2460 /* If STEP is set, it's a request to use hardware stepping
2461 facilities. But in that case, we should never
2462 use singlestep breakpoint. */
2463 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2465 /* Decide the set of threads to ask the target to resume. */
2466 if (tp
->control
.trap_expected
)
2468 /* We're allowing a thread to run past a breakpoint it has
2469 hit, either by single-stepping the thread with the breakpoint
2470 removed, or by displaced stepping, with the breakpoint inserted.
2471 In the former case, we need to single-step only this thread,
2472 and keep others stopped, as they can miss this breakpoint if
2473 allowed to run. That's not really a problem for displaced
2474 stepping, but, we still keep other threads stopped, in case
2475 another thread is also stopped for a breakpoint waiting for
2476 its turn in the displaced stepping queue. */
2477 resume_ptid
= inferior_ptid
;
2480 resume_ptid
= internal_resume_ptid (user_step
);
2482 if (execution_direction
!= EXEC_REVERSE
2483 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2485 /* There are two cases where we currently need to step a
2486 breakpoint instruction when we have a signal to deliver:
2488 - See handle_signal_stop where we handle random signals that
2489 could take out us out of the stepping range. Normally, in
2490 that case we end up continuing (instead of stepping) over the
2491 signal handler with a breakpoint at PC, but there are cases
2492 where we should _always_ single-step, even if we have a
2493 step-resume breakpoint, like when a software watchpoint is
2494 set. Assuming single-stepping and delivering a signal at the
2495 same time would takes us to the signal handler, then we could
2496 have removed the breakpoint at PC to step over it. However,
2497 some hardware step targets (like e.g., Mac OS) can't step
2498 into signal handlers, and for those, we need to leave the
2499 breakpoint at PC inserted, as otherwise if the handler
2500 recurses and executes PC again, it'll miss the breakpoint.
2501 So we leave the breakpoint inserted anyway, but we need to
2502 record that we tried to step a breakpoint instruction, so
2503 that adjust_pc_after_break doesn't end up confused.
2505 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2506 in one thread after another thread that was stepping had been
2507 momentarily paused for a step-over. When we re-resume the
2508 stepping thread, it may be resumed from that address with a
2509 breakpoint that hasn't trapped yet. Seen with
2510 gdb.threads/non-stop-fair-events.exp, on targets that don't
2511 do displaced stepping. */
2513 infrun_debug_printf ("resume: [%s] stepped breakpoint",
2514 target_pid_to_str (tp
->ptid
).c_str ());
2516 tp
->stepped_breakpoint
= 1;
2518 /* Most targets can step a breakpoint instruction, thus
2519 executing it normally. But if this one cannot, just
2520 continue and we will hit it anyway. */
2521 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2526 && tp
->control
.trap_expected
2527 && use_displaced_stepping (tp
)
2528 && !step_over_info_valid_p ())
2530 struct regcache
*resume_regcache
= get_thread_regcache (tp
);
2531 struct gdbarch
*resume_gdbarch
= resume_regcache
->arch ();
2532 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2535 read_memory (actual_pc
, buf
, sizeof (buf
));
2536 displaced_debug_printf ("run %s: %s",
2537 paddress (resume_gdbarch
, actual_pc
),
2538 displaced_step_dump_bytes
2539 (buf
, sizeof (buf
)).c_str ());
2542 if (tp
->control
.may_range_step
)
2544 /* If we're resuming a thread with the PC out of the step
2545 range, then we're doing some nested/finer run control
2546 operation, like stepping the thread out of the dynamic
2547 linker or the displaced stepping scratch pad. We
2548 shouldn't have allowed a range step then. */
2549 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2552 do_target_resume (resume_ptid
, step
, sig
);
2556 /* Resume the inferior. SIG is the signal to give the inferior
2557 (GDB_SIGNAL_0 for none). This is a wrapper around 'resume_1' that
2558 rolls back state on error. */
2561 resume (gdb_signal sig
)
2567 catch (const gdb_exception
&ex
)
2569 /* If resuming is being aborted for any reason, delete any
2570 single-step breakpoint resume_1 may have created, to avoid
2571 confusing the following resumption, and to avoid leaving
2572 single-step breakpoints perturbing other threads, in case
2573 we're running in non-stop mode. */
2574 if (inferior_ptid
!= null_ptid
)
2575 delete_single_step_breakpoints (inferior_thread ());
2585 /* Counter that tracks number of user visible stops. This can be used
2586 to tell whether a command has proceeded the inferior past the
2587 current location. This allows e.g., inferior function calls in
2588 breakpoint commands to not interrupt the command list. When the
2589 call finishes successfully, the inferior is standing at the same
2590 breakpoint as if nothing happened (and so we don't call
2592 static ULONGEST current_stop_id
;
2599 return current_stop_id
;
2602 /* Called when we report a user visible stop. */
2610 /* Clear out all variables saying what to do when inferior is continued.
2611 First do this, then set the ones you want, then call `proceed'. */
2614 clear_proceed_status_thread (struct thread_info
*tp
)
2616 infrun_debug_printf ("%s", target_pid_to_str (tp
->ptid
).c_str ());
2618 /* If we're starting a new sequence, then the previous finished
2619 single-step is no longer relevant. */
2620 if (tp
->suspend
.waitstatus_pending_p
)
2622 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
2624 infrun_debug_printf ("pending event of %s was a finished step. "
2626 target_pid_to_str (tp
->ptid
).c_str ());
2628 tp
->suspend
.waitstatus_pending_p
= 0;
2629 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2634 ("thread %s has pending wait status %s (currently_stepping=%d).",
2635 target_pid_to_str (tp
->ptid
).c_str (),
2636 target_waitstatus_to_string (&tp
->suspend
.waitstatus
).c_str (),
2637 currently_stepping (tp
));
2641 /* If this signal should not be seen by program, give it zero.
2642 Used for debugging signals. */
2643 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2644 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2646 delete tp
->thread_fsm
;
2647 tp
->thread_fsm
= NULL
;
2649 tp
->control
.trap_expected
= 0;
2650 tp
->control
.step_range_start
= 0;
2651 tp
->control
.step_range_end
= 0;
2652 tp
->control
.may_range_step
= 0;
2653 tp
->control
.step_frame_id
= null_frame_id
;
2654 tp
->control
.step_stack_frame_id
= null_frame_id
;
2655 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2656 tp
->control
.step_start_function
= NULL
;
2657 tp
->stop_requested
= 0;
2659 tp
->control
.stop_step
= 0;
2661 tp
->control
.proceed_to_finish
= 0;
2663 tp
->control
.stepping_command
= 0;
2665 /* Discard any remaining commands or status from previous stop. */
2666 bpstat_clear (&tp
->control
.stop_bpstat
);
2670 clear_proceed_status (int step
)
2672 /* With scheduler-locking replay, stop replaying other threads if we're
2673 not replaying the user-visible resume ptid.
2675 This is a convenience feature to not require the user to explicitly
2676 stop replaying the other threads. We're assuming that the user's
2677 intent is to resume tracing the recorded process. */
2678 if (!non_stop
&& scheduler_mode
== schedlock_replay
2679 && target_record_is_replaying (minus_one_ptid
)
2680 && !target_record_will_replay (user_visible_resume_ptid (step
),
2681 execution_direction
))
2682 target_record_stop_replaying ();
2684 if (!non_stop
&& inferior_ptid
!= null_ptid
)
2686 ptid_t resume_ptid
= user_visible_resume_ptid (step
);
2687 process_stratum_target
*resume_target
2688 = user_visible_resume_target (resume_ptid
);
2690 /* In all-stop mode, delete the per-thread status of all threads
2691 we're about to resume, implicitly and explicitly. */
2692 for (thread_info
*tp
: all_non_exited_threads (resume_target
, resume_ptid
))
2693 clear_proceed_status_thread (tp
);
2696 if (inferior_ptid
!= null_ptid
)
2698 struct inferior
*inferior
;
2702 /* If in non-stop mode, only delete the per-thread status of
2703 the current thread. */
2704 clear_proceed_status_thread (inferior_thread ());
2707 inferior
= current_inferior ();
2708 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2711 gdb::observers::about_to_proceed
.notify ();
2714 /* Returns true if TP is still stopped at a breakpoint that needs
2715 stepping-over in order to make progress. If the breakpoint is gone
2716 meanwhile, we can skip the whole step-over dance. */
2719 thread_still_needs_step_over_bp (struct thread_info
*tp
)
2721 if (tp
->stepping_over_breakpoint
)
2723 struct regcache
*regcache
= get_thread_regcache (tp
);
2725 if (breakpoint_here_p (regcache
->aspace (),
2726 regcache_read_pc (regcache
))
2727 == ordinary_breakpoint_here
)
2730 tp
->stepping_over_breakpoint
= 0;
2736 /* Check whether thread TP still needs to start a step-over in order
2737 to make progress when resumed. Returns an bitwise or of enum
2738 step_over_what bits, indicating what needs to be stepped over. */
2740 static step_over_what
2741 thread_still_needs_step_over (struct thread_info
*tp
)
2743 step_over_what what
= 0;
2745 if (thread_still_needs_step_over_bp (tp
))
2746 what
|= STEP_OVER_BREAKPOINT
;
2748 if (tp
->stepping_over_watchpoint
2749 && !target_have_steppable_watchpoint ())
2750 what
|= STEP_OVER_WATCHPOINT
;
2755 /* Returns true if scheduler locking applies. STEP indicates whether
2756 we're about to do a step/next-like command to a thread. */
2759 schedlock_applies (struct thread_info
*tp
)
2761 return (scheduler_mode
== schedlock_on
2762 || (scheduler_mode
== schedlock_step
2763 && tp
->control
.stepping_command
)
2764 || (scheduler_mode
== schedlock_replay
2765 && target_record_will_replay (minus_one_ptid
,
2766 execution_direction
)));
2769 /* Set process_stratum_target::COMMIT_RESUMED_STATE in all target
2770 stacks that have threads executing and don't have threads with
2774 maybe_set_commit_resumed_all_targets ()
2776 scoped_restore_current_thread restore_thread
;
2778 for (inferior
*inf
: all_non_exited_inferiors ())
2780 process_stratum_target
*proc_target
= inf
->process_target ();
2782 if (proc_target
->commit_resumed_state
)
2784 /* We already set this in a previous iteration, via another
2785 inferior sharing the process_stratum target. */
2789 /* If the target has no resumed threads, it would be useless to
2790 ask it to commit the resumed threads. */
2791 if (!proc_target
->threads_executing
)
2793 infrun_debug_printf ("not requesting commit-resumed for target "
2794 "%s, no resumed threads",
2795 proc_target
->shortname ());
2799 /* As an optimization, if a thread from this target has some
2800 status to report, handle it before requiring the target to
2801 commit its resumed threads: handling the status might lead to
2802 resuming more threads. */
2803 bool has_thread_with_pending_status
= false;
2804 for (thread_info
*thread
: all_non_exited_threads (proc_target
))
2805 if (thread
->resumed
&& thread
->suspend
.waitstatus_pending_p
)
2807 has_thread_with_pending_status
= true;
2811 if (has_thread_with_pending_status
)
2813 infrun_debug_printf ("not requesting commit-resumed for target %s, a"
2814 " thread has a pending waitstatus",
2815 proc_target
->shortname ());
2819 switch_to_inferior_no_thread (inf
);
2821 if (target_has_pending_events ())
2823 infrun_debug_printf ("not requesting commit-resumed for target %s, "
2824 "target has pending events",
2825 proc_target
->shortname ());
2829 infrun_debug_printf ("enabling commit-resumed for target %s",
2830 proc_target
->shortname ());
2832 proc_target
->commit_resumed_state
= true;
2839 maybe_call_commit_resumed_all_targets ()
2841 scoped_restore_current_thread restore_thread
;
2843 for (inferior
*inf
: all_non_exited_inferiors ())
2845 process_stratum_target
*proc_target
= inf
->process_target ();
2847 if (!proc_target
->commit_resumed_state
)
2850 switch_to_inferior_no_thread (inf
);
2852 infrun_debug_printf ("calling commit_resumed for target %s",
2853 proc_target
->shortname());
2855 target_commit_resumed ();
2859 /* To track nesting of scoped_disable_commit_resumed objects, ensuring
2860 that only the outermost one attempts to re-enable
2862 static bool enable_commit_resumed
= true;
2866 scoped_disable_commit_resumed::scoped_disable_commit_resumed
2867 (const char *reason
)
2868 : m_reason (reason
),
2869 m_prev_enable_commit_resumed (enable_commit_resumed
)
2871 infrun_debug_printf ("reason=%s", m_reason
);
2873 enable_commit_resumed
= false;
2875 for (inferior
*inf
: all_non_exited_inferiors ())
2877 process_stratum_target
*proc_target
= inf
->process_target ();
2879 if (m_prev_enable_commit_resumed
)
2881 /* This is the outermost instance: force all
2882 COMMIT_RESUMED_STATE to false. */
2883 proc_target
->commit_resumed_state
= false;
2887 /* This is not the outermost instance, we expect
2888 COMMIT_RESUMED_STATE to have been cleared by the
2889 outermost instance. */
2890 gdb_assert (!proc_target
->commit_resumed_state
);
2898 scoped_disable_commit_resumed::reset ()
2904 infrun_debug_printf ("reason=%s", m_reason
);
2906 gdb_assert (!enable_commit_resumed
);
2908 enable_commit_resumed
= m_prev_enable_commit_resumed
;
2910 if (m_prev_enable_commit_resumed
)
2912 /* This is the outermost instance, re-enable
2913 COMMIT_RESUMED_STATE on the targets where it's possible. */
2914 maybe_set_commit_resumed_all_targets ();
2918 /* This is not the outermost instance, we expect
2919 COMMIT_RESUMED_STATE to still be false. */
2920 for (inferior
*inf
: all_non_exited_inferiors ())
2922 process_stratum_target
*proc_target
= inf
->process_target ();
2923 gdb_assert (!proc_target
->commit_resumed_state
);
2930 scoped_disable_commit_resumed::~scoped_disable_commit_resumed ()
2938 scoped_disable_commit_resumed::reset_and_commit ()
2941 maybe_call_commit_resumed_all_targets ();
2946 scoped_enable_commit_resumed::scoped_enable_commit_resumed
2947 (const char *reason
)
2948 : m_reason (reason
),
2949 m_prev_enable_commit_resumed (enable_commit_resumed
)
2951 infrun_debug_printf ("reason=%s", m_reason
);
2953 if (!enable_commit_resumed
)
2955 enable_commit_resumed
= true;
2957 /* Re-enable COMMIT_RESUMED_STATE on the targets where it's
2959 maybe_set_commit_resumed_all_targets ();
2961 maybe_call_commit_resumed_all_targets ();
2967 scoped_enable_commit_resumed::~scoped_enable_commit_resumed ()
2969 infrun_debug_printf ("reason=%s", m_reason
);
2971 gdb_assert (enable_commit_resumed
);
2973 enable_commit_resumed
= m_prev_enable_commit_resumed
;
2975 if (!enable_commit_resumed
)
2977 /* Force all COMMIT_RESUMED_STATE back to false. */
2978 for (inferior
*inf
: all_non_exited_inferiors ())
2980 process_stratum_target
*proc_target
= inf
->process_target ();
2981 proc_target
->commit_resumed_state
= false;
2986 /* Check that all the targets we're about to resume are in non-stop
2987 mode. Ideally, we'd only care whether all targets support
2988 target-async, but we're not there yet. E.g., stop_all_threads
2989 doesn't know how to handle all-stop targets. Also, the remote
2990 protocol in all-stop mode is synchronous, irrespective of
2991 target-async, which means that things like a breakpoint re-set
2992 triggered by one target would try to read memory from all targets
2996 check_multi_target_resumption (process_stratum_target
*resume_target
)
2998 if (!non_stop
&& resume_target
== nullptr)
3000 scoped_restore_current_thread restore_thread
;
3002 /* This is used to track whether we're resuming more than one
3004 process_stratum_target
*first_connection
= nullptr;
3006 /* The first inferior we see with a target that does not work in
3007 always-non-stop mode. */
3008 inferior
*first_not_non_stop
= nullptr;
3010 for (inferior
*inf
: all_non_exited_inferiors ())
3012 switch_to_inferior_no_thread (inf
);
3014 if (!target_has_execution ())
3017 process_stratum_target
*proc_target
3018 = current_inferior ()->process_target();
3020 if (!target_is_non_stop_p ())
3021 first_not_non_stop
= inf
;
3023 if (first_connection
== nullptr)
3024 first_connection
= proc_target
;
3025 else if (first_connection
!= proc_target
3026 && first_not_non_stop
!= nullptr)
3028 switch_to_inferior_no_thread (first_not_non_stop
);
3030 proc_target
= current_inferior ()->process_target();
3032 error (_("Connection %d (%s) does not support "
3033 "multi-target resumption."),
3034 proc_target
->connection_number
,
3035 make_target_connection_string (proc_target
).c_str ());
3041 /* Basic routine for continuing the program in various fashions.
3043 ADDR is the address to resume at, or -1 for resume where stopped.
3044 SIGGNAL is the signal to give it, or GDB_SIGNAL_0 for none,
3045 or GDB_SIGNAL_DEFAULT for act according to how it stopped.
3047 You should call clear_proceed_status before calling proceed. */
3050 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
)
3052 INFRUN_SCOPED_DEBUG_ENTER_EXIT
;
3054 struct regcache
*regcache
;
3055 struct gdbarch
*gdbarch
;
3057 struct execution_control_state ecss
;
3058 struct execution_control_state
*ecs
= &ecss
;
3061 /* If we're stopped at a fork/vfork, follow the branch set by the
3062 "set follow-fork-mode" command; otherwise, we'll just proceed
3063 resuming the current thread. */
3064 if (!follow_fork ())
3066 /* The target for some reason decided not to resume. */
3068 if (target_can_async_p ())
3069 inferior_event_handler (INF_EXEC_COMPLETE
);
3073 /* We'll update this if & when we switch to a new thread. */
3074 previous_inferior_ptid
= inferior_ptid
;
3076 regcache
= get_current_regcache ();
3077 gdbarch
= regcache
->arch ();
3078 const address_space
*aspace
= regcache
->aspace ();
3080 pc
= regcache_read_pc_protected (regcache
);
3082 thread_info
*cur_thr
= inferior_thread ();
3084 /* Fill in with reasonable starting values. */
3085 init_thread_stepping_state (cur_thr
);
3087 gdb_assert (!thread_is_in_step_over_chain (cur_thr
));
3090 = user_visible_resume_ptid (cur_thr
->control
.stepping_command
);
3091 process_stratum_target
*resume_target
3092 = user_visible_resume_target (resume_ptid
);
3094 check_multi_target_resumption (resume_target
);
3096 if (addr
== (CORE_ADDR
) -1)
3098 if (pc
== cur_thr
->suspend
.stop_pc
3099 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
3100 && execution_direction
!= EXEC_REVERSE
)
3101 /* There is a breakpoint at the address we will resume at,
3102 step one instruction before inserting breakpoints so that
3103 we do not stop right away (and report a second hit at this
3106 Note, we don't do this in reverse, because we won't
3107 actually be executing the breakpoint insn anyway.
3108 We'll be (un-)executing the previous instruction. */
3109 cur_thr
->stepping_over_breakpoint
= 1;
3110 else if (gdbarch_single_step_through_delay_p (gdbarch
)
3111 && gdbarch_single_step_through_delay (gdbarch
,
3112 get_current_frame ()))
3113 /* We stepped onto an instruction that needs to be stepped
3114 again before re-inserting the breakpoint, do so. */
3115 cur_thr
->stepping_over_breakpoint
= 1;
3119 regcache_write_pc (regcache
, addr
);
3122 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
3123 cur_thr
->suspend
.stop_signal
= siggnal
;
3125 /* If an exception is thrown from this point on, make sure to
3126 propagate GDB's knowledge of the executing state to the
3127 frontend/user running state. */
3128 scoped_finish_thread_state
finish_state (resume_target
, resume_ptid
);
3130 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
3131 threads (e.g., we might need to set threads stepping over
3132 breakpoints first), from the user/frontend's point of view, all
3133 threads in RESUME_PTID are now running. Unless we're calling an
3134 inferior function, as in that case we pretend the inferior
3135 doesn't run at all. */
3136 if (!cur_thr
->control
.in_infcall
)
3137 set_running (resume_target
, resume_ptid
, true);
3139 infrun_debug_printf ("addr=%s, signal=%s", paddress (gdbarch
, addr
),
3140 gdb_signal_to_symbol_string (siggnal
));
3142 annotate_starting ();
3144 /* Make sure that output from GDB appears before output from the
3146 gdb_flush (gdb_stdout
);
3148 /* Since we've marked the inferior running, give it the terminal. A
3149 QUIT/Ctrl-C from here on is forwarded to the target (which can
3150 still detect attempts to unblock a stuck connection with repeated
3151 Ctrl-C from within target_pass_ctrlc). */
3152 target_terminal::inferior ();
3154 /* In a multi-threaded task we may select another thread and
3155 then continue or step.
3157 But if a thread that we're resuming had stopped at a breakpoint,
3158 it will immediately cause another breakpoint stop without any
3159 execution (i.e. it will report a breakpoint hit incorrectly). So
3160 we must step over it first.
3162 Look for threads other than the current (TP) that reported a
3163 breakpoint hit and haven't been resumed yet since. */
3165 /* If scheduler locking applies, we can avoid iterating over all
3167 if (!non_stop
&& !schedlock_applies (cur_thr
))
3169 for (thread_info
*tp
: all_non_exited_threads (resume_target
,
3172 switch_to_thread_no_regs (tp
);
3174 /* Ignore the current thread here. It's handled
3179 if (!thread_still_needs_step_over (tp
))
3182 gdb_assert (!thread_is_in_step_over_chain (tp
));
3184 infrun_debug_printf ("need to step-over [%s] first",
3185 target_pid_to_str (tp
->ptid
).c_str ());
3187 global_thread_step_over_chain_enqueue (tp
);
3190 switch_to_thread (cur_thr
);
3193 /* Enqueue the current thread last, so that we move all other
3194 threads over their breakpoints first. */
3195 if (cur_thr
->stepping_over_breakpoint
)
3196 global_thread_step_over_chain_enqueue (cur_thr
);
3198 /* If the thread isn't started, we'll still need to set its prev_pc,
3199 so that switch_back_to_stepped_thread knows the thread hasn't
3200 advanced. Must do this before resuming any thread, as in
3201 all-stop/remote, once we resume we can't send any other packet
3202 until the target stops again. */
3203 cur_thr
->prev_pc
= regcache_read_pc_protected (regcache
);
3206 scoped_disable_commit_resumed
disable_commit_resumed ("proceeding");
3208 started
= start_step_over ();
3210 if (step_over_info_valid_p ())
3212 /* Either this thread started a new in-line step over, or some
3213 other thread was already doing one. In either case, don't
3214 resume anything else until the step-over is finished. */
3216 else if (started
&& !target_is_non_stop_p ())
3218 /* A new displaced stepping sequence was started. In all-stop,
3219 we can't talk to the target anymore until it next stops. */
3221 else if (!non_stop
&& target_is_non_stop_p ())
3223 INFRUN_SCOPED_DEBUG_START_END
3224 ("resuming threads, all-stop-on-top-of-non-stop");
3226 /* In all-stop, but the target is always in non-stop mode.
3227 Start all other threads that are implicitly resumed too. */
3228 for (thread_info
*tp
: all_non_exited_threads (resume_target
,
3231 switch_to_thread_no_regs (tp
);
3233 if (!tp
->inf
->has_execution ())
3235 infrun_debug_printf ("[%s] target has no execution",
3236 target_pid_to_str (tp
->ptid
).c_str ());
3242 infrun_debug_printf ("[%s] resumed",
3243 target_pid_to_str (tp
->ptid
).c_str ());
3244 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
3248 if (thread_is_in_step_over_chain (tp
))
3250 infrun_debug_printf ("[%s] needs step-over",
3251 target_pid_to_str (tp
->ptid
).c_str ());
3255 infrun_debug_printf ("resuming %s",
3256 target_pid_to_str (tp
->ptid
).c_str ());
3258 reset_ecs (ecs
, tp
);
3259 switch_to_thread (tp
);
3260 keep_going_pass_signal (ecs
);
3261 if (!ecs
->wait_some_more
)
3262 error (_("Command aborted."));
3265 else if (!cur_thr
->resumed
&& !thread_is_in_step_over_chain (cur_thr
))
3267 /* The thread wasn't started, and isn't queued, run it now. */
3268 reset_ecs (ecs
, cur_thr
);
3269 switch_to_thread (cur_thr
);
3270 keep_going_pass_signal (ecs
);
3271 if (!ecs
->wait_some_more
)
3272 error (_("Command aborted."));
3275 disable_commit_resumed
.reset_and_commit ();
3278 finish_state
.release ();
3280 /* If we've switched threads above, switch back to the previously
3281 current thread. We don't want the user to see a different
3283 switch_to_thread (cur_thr
);
3285 /* Tell the event loop to wait for it to stop. If the target
3286 supports asynchronous execution, it'll do this from within
3288 if (!target_can_async_p ())
3289 mark_async_event_handler (infrun_async_inferior_event_token
);
3293 /* Start remote-debugging of a machine over a serial link. */
3296 start_remote (int from_tty
)
3298 inferior
*inf
= current_inferior ();
3299 inf
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
3301 /* Always go on waiting for the target, regardless of the mode. */
3302 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3303 indicate to wait_for_inferior that a target should timeout if
3304 nothing is returned (instead of just blocking). Because of this,
3305 targets expecting an immediate response need to, internally, set
3306 things up so that the target_wait() is forced to eventually
3308 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3309 differentiate to its caller what the state of the target is after
3310 the initial open has been performed. Here we're assuming that
3311 the target has stopped. It should be possible to eventually have
3312 target_open() return to the caller an indication that the target
3313 is currently running and GDB state should be set to the same as
3314 for an async run. */
3315 wait_for_inferior (inf
);
3317 /* Now that the inferior has stopped, do any bookkeeping like
3318 loading shared libraries. We want to do this before normal_stop,
3319 so that the displayed frame is up to date. */
3320 post_create_inferior (from_tty
);
3325 /* Initialize static vars when a new inferior begins. */
3328 init_wait_for_inferior (void)
3330 /* These are meaningless until the first time through wait_for_inferior. */
3332 breakpoint_init_inferior (inf_starting
);
3334 clear_proceed_status (0);
3336 nullify_last_target_wait_ptid ();
3338 previous_inferior_ptid
= inferior_ptid
;
3343 static void handle_inferior_event (struct execution_control_state
*ecs
);
3345 static void handle_step_into_function (struct gdbarch
*gdbarch
,
3346 struct execution_control_state
*ecs
);
3347 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
3348 struct execution_control_state
*ecs
);
3349 static void handle_signal_stop (struct execution_control_state
*ecs
);
3350 static void check_exception_resume (struct execution_control_state
*,
3351 struct frame_info
*);
3353 static void end_stepping_range (struct execution_control_state
*ecs
);
3354 static void stop_waiting (struct execution_control_state
*ecs
);
3355 static void keep_going (struct execution_control_state
*ecs
);
3356 static void process_event_stop_test (struct execution_control_state
*ecs
);
3357 static bool switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
3359 /* This function is attached as a "thread_stop_requested" observer.
3360 Cleanup local state that assumed the PTID was to be resumed, and
3361 report the stop to the frontend. */
3364 infrun_thread_stop_requested (ptid_t ptid
)
3366 process_stratum_target
*curr_target
= current_inferior ()->process_target ();
3368 /* PTID was requested to stop. If the thread was already stopped,
3369 but the user/frontend doesn't know about that yet (e.g., the
3370 thread had been temporarily paused for some step-over), set up
3371 for reporting the stop now. */
3372 for (thread_info
*tp
: all_threads (curr_target
, ptid
))
3374 if (tp
->state
!= THREAD_RUNNING
)
3379 /* Remove matching threads from the step-over queue, so
3380 start_step_over doesn't try to resume them
3382 if (thread_is_in_step_over_chain (tp
))
3383 global_thread_step_over_chain_remove (tp
);
3385 /* If the thread is stopped, but the user/frontend doesn't
3386 know about that yet, queue a pending event, as if the
3387 thread had just stopped now. Unless the thread already had
3389 if (!tp
->suspend
.waitstatus_pending_p
)
3391 tp
->suspend
.waitstatus_pending_p
= 1;
3392 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_STOPPED
;
3393 tp
->suspend
.waitstatus
.value
.sig
= GDB_SIGNAL_0
;
3396 /* Clear the inline-frame state, since we're re-processing the
3398 clear_inline_frame_state (tp
);
3400 /* If this thread was paused because some other thread was
3401 doing an inline-step over, let that finish first. Once
3402 that happens, we'll restart all threads and consume pending
3403 stop events then. */
3404 if (step_over_info_valid_p ())
3407 /* Otherwise we can process the (new) pending event now. Set
3408 it so this pending event is considered by
3415 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
3417 if (target_last_proc_target
== tp
->inf
->process_target ()
3418 && target_last_wait_ptid
== tp
->ptid
)
3419 nullify_last_target_wait_ptid ();
3422 /* Delete the step resume, single-step and longjmp/exception resume
3423 breakpoints of TP. */
3426 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
3428 delete_step_resume_breakpoint (tp
);
3429 delete_exception_resume_breakpoint (tp
);
3430 delete_single_step_breakpoints (tp
);
3433 /* If the target still has execution, call FUNC for each thread that
3434 just stopped. In all-stop, that's all the non-exited threads; in
3435 non-stop, that's the current thread, only. */
3437 typedef void (*for_each_just_stopped_thread_callback_func
)
3438 (struct thread_info
*tp
);
3441 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
3443 if (!target_has_execution () || inferior_ptid
== null_ptid
)
3446 if (target_is_non_stop_p ())
3448 /* If in non-stop mode, only the current thread stopped. */
3449 func (inferior_thread ());
3453 /* In all-stop mode, all threads have stopped. */
3454 for (thread_info
*tp
: all_non_exited_threads ())
3459 /* Delete the step resume and longjmp/exception resume breakpoints of
3460 the threads that just stopped. */
3463 delete_just_stopped_threads_infrun_breakpoints (void)
3465 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3468 /* Delete the single-step breakpoints of the threads that just
3472 delete_just_stopped_threads_single_step_breakpoints (void)
3474 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3480 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3481 const struct target_waitstatus
*ws
)
3483 infrun_debug_printf ("target_wait (%d.%ld.%ld [%s], status) =",
3487 target_pid_to_str (waiton_ptid
).c_str ());
3488 infrun_debug_printf (" %d.%ld.%ld [%s],",
3492 target_pid_to_str (result_ptid
).c_str ());
3493 infrun_debug_printf (" %s", target_waitstatus_to_string (ws
).c_str ());
3496 /* Select a thread at random, out of those which are resumed and have
3499 static struct thread_info
*
3500 random_pending_event_thread (inferior
*inf
, ptid_t waiton_ptid
)
3504 auto has_event
= [&] (thread_info
*tp
)
3506 return (tp
->ptid
.matches (waiton_ptid
)
3508 && tp
->suspend
.waitstatus_pending_p
);
3511 /* First see how many events we have. Count only resumed threads
3512 that have an event pending. */
3513 for (thread_info
*tp
: inf
->non_exited_threads ())
3517 if (num_events
== 0)
3520 /* Now randomly pick a thread out of those that have had events. */
3521 int random_selector
= (int) ((num_events
* (double) rand ())
3522 / (RAND_MAX
+ 1.0));
3525 infrun_debug_printf ("Found %d events, selecting #%d",
3526 num_events
, random_selector
);
3528 /* Select the Nth thread that has had an event. */
3529 for (thread_info
*tp
: inf
->non_exited_threads ())
3531 if (random_selector
-- == 0)
3534 gdb_assert_not_reached ("event thread not found");
3537 /* Wrapper for target_wait that first checks whether threads have
3538 pending statuses to report before actually asking the target for
3539 more events. INF is the inferior we're using to call target_wait
3543 do_target_wait_1 (inferior
*inf
, ptid_t ptid
,
3544 target_waitstatus
*status
, target_wait_flags options
)
3547 struct thread_info
*tp
;
3549 /* We know that we are looking for an event in the target of inferior
3550 INF, but we don't know which thread the event might come from. As
3551 such we want to make sure that INFERIOR_PTID is reset so that none of
3552 the wait code relies on it - doing so is always a mistake. */
3553 switch_to_inferior_no_thread (inf
);
3555 /* First check if there is a resumed thread with a wait status
3557 if (ptid
== minus_one_ptid
|| ptid
.is_pid ())
3559 tp
= random_pending_event_thread (inf
, ptid
);
3563 infrun_debug_printf ("Waiting for specific thread %s.",
3564 target_pid_to_str (ptid
).c_str ());
3566 /* We have a specific thread to check. */
3567 tp
= find_thread_ptid (inf
, ptid
);
3568 gdb_assert (tp
!= NULL
);
3569 if (!tp
->suspend
.waitstatus_pending_p
)
3574 && (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3575 || tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
3577 struct regcache
*regcache
= get_thread_regcache (tp
);
3578 struct gdbarch
*gdbarch
= regcache
->arch ();
3582 pc
= regcache_read_pc (regcache
);
3584 if (pc
!= tp
->suspend
.stop_pc
)
3586 infrun_debug_printf ("PC of %s changed. was=%s, now=%s",
3587 target_pid_to_str (tp
->ptid
).c_str (),
3588 paddress (gdbarch
, tp
->suspend
.stop_pc
),
3589 paddress (gdbarch
, pc
));
3592 else if (!breakpoint_inserted_here_p (regcache
->aspace (), pc
))
3594 infrun_debug_printf ("previous breakpoint of %s, at %s gone",
3595 target_pid_to_str (tp
->ptid
).c_str (),
3596 paddress (gdbarch
, pc
));
3603 infrun_debug_printf ("pending event of %s cancelled.",
3604 target_pid_to_str (tp
->ptid
).c_str ());
3606 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_SPURIOUS
;
3607 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3613 infrun_debug_printf ("Using pending wait status %s for %s.",
3614 target_waitstatus_to_string
3615 (&tp
->suspend
.waitstatus
).c_str (),
3616 target_pid_to_str (tp
->ptid
).c_str ());
3618 /* Now that we've selected our final event LWP, un-adjust its PC
3619 if it was a software breakpoint (and the target doesn't
3620 always adjust the PC itself). */
3621 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3622 && !target_supports_stopped_by_sw_breakpoint ())
3624 struct regcache
*regcache
;
3625 struct gdbarch
*gdbarch
;
3628 regcache
= get_thread_regcache (tp
);
3629 gdbarch
= regcache
->arch ();
3631 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3636 pc
= regcache_read_pc (regcache
);
3637 regcache_write_pc (regcache
, pc
+ decr_pc
);
3641 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3642 *status
= tp
->suspend
.waitstatus
;
3643 tp
->suspend
.waitstatus_pending_p
= 0;
3645 /* Wake up the event loop again, until all pending events are
3647 if (target_is_async_p ())
3648 mark_async_event_handler (infrun_async_inferior_event_token
);
3652 /* But if we don't find one, we'll have to wait. */
3654 /* We can't ask a non-async target to do a non-blocking wait, so this will be
3656 if (!target_can_async_p ())
3657 options
&= ~TARGET_WNOHANG
;
3659 if (deprecated_target_wait_hook
)
3660 event_ptid
= deprecated_target_wait_hook (ptid
, status
, options
);
3662 event_ptid
= target_wait (ptid
, status
, options
);
3667 /* Wrapper for target_wait that first checks whether threads have
3668 pending statuses to report before actually asking the target for
3669 more events. Polls for events from all inferiors/targets. */
3672 do_target_wait (execution_control_state
*ecs
, target_wait_flags options
)
3674 int num_inferiors
= 0;
3675 int random_selector
;
3677 /* For fairness, we pick the first inferior/target to poll at random
3678 out of all inferiors that may report events, and then continue
3679 polling the rest of the inferior list starting from that one in a
3680 circular fashion until the whole list is polled once. */
3682 auto inferior_matches
= [] (inferior
*inf
)
3684 return inf
->process_target () != nullptr;
3687 /* First see how many matching inferiors we have. */
3688 for (inferior
*inf
: all_inferiors ())
3689 if (inferior_matches (inf
))
3692 if (num_inferiors
== 0)
3694 ecs
->ws
.kind
= TARGET_WAITKIND_IGNORE
;
3698 /* Now randomly pick an inferior out of those that matched. */
3699 random_selector
= (int)
3700 ((num_inferiors
* (double) rand ()) / (RAND_MAX
+ 1.0));
3702 if (num_inferiors
> 1)
3703 infrun_debug_printf ("Found %d inferiors, starting at #%d",
3704 num_inferiors
, random_selector
);
3706 /* Select the Nth inferior that matched. */
3708 inferior
*selected
= nullptr;
3710 for (inferior
*inf
: all_inferiors ())
3711 if (inferior_matches (inf
))
3712 if (random_selector
-- == 0)
3718 /* Now poll for events out of each of the matching inferior's
3719 targets, starting from the selected one. */
3721 auto do_wait
= [&] (inferior
*inf
)
3723 ecs
->ptid
= do_target_wait_1 (inf
, minus_one_ptid
, &ecs
->ws
, options
);
3724 ecs
->target
= inf
->process_target ();
3725 return (ecs
->ws
.kind
!= TARGET_WAITKIND_IGNORE
);
3728 /* Needed in 'all-stop + target-non-stop' mode, because we end up
3729 here spuriously after the target is all stopped and we've already
3730 reported the stop to the user, polling for events. */
3731 scoped_restore_current_thread restore_thread
;
3733 intrusive_list_iterator
<inferior
> start
3734 = inferior_list
.iterator_to (*selected
);
3736 for (intrusive_list_iterator
<inferior
> it
= start
;
3737 it
!= inferior_list
.end ();
3740 inferior
*inf
= &*it
;
3742 if (inferior_matches (inf
) && do_wait (inf
))
3746 for (intrusive_list_iterator
<inferior
> it
= inferior_list
.begin ();
3750 inferior
*inf
= &*it
;
3752 if (inferior_matches (inf
) && do_wait (inf
))
3756 ecs
->ws
.kind
= TARGET_WAITKIND_IGNORE
;
3760 /* An event reported by wait_one. */
3762 struct wait_one_event
3764 /* The target the event came out of. */
3765 process_stratum_target
*target
;
3767 /* The PTID the event was for. */
3770 /* The waitstatus. */
3771 target_waitstatus ws
;
3774 static bool handle_one (const wait_one_event
&event
);
3775 static void restart_threads (struct thread_info
*event_thread
);
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 (void)
4970 /* We may need multiple passes to discover all threads. */
4974 gdb_assert (exists_non_stop_target ());
4976 infrun_debug_printf ("starting");
4978 scoped_restore_current_thread restore_thread
;
4980 /* Enable thread events of all targets. */
4981 for (auto *target
: all_non_exited_process_targets ())
4983 switch_to_target_no_thread (target
);
4984 target_thread_events (true);
4989 /* Disable thread events of all targets. */
4990 for (auto *target
: all_non_exited_process_targets ())
4992 switch_to_target_no_thread (target
);
4993 target_thread_events (false);
4996 /* Use debug_prefixed_printf directly to get a meaningful function
4999 debug_prefixed_printf ("infrun", "stop_all_threads", "done");
5002 /* Request threads to stop, and then wait for the stops. Because
5003 threads we already know about can spawn more threads while we're
5004 trying to stop them, and we only learn about new threads when we
5005 update the thread list, do this in a loop, and keep iterating
5006 until two passes find no threads that need to be stopped. */
5007 for (pass
= 0; pass
< 2; pass
++, iterations
++)
5009 infrun_debug_printf ("pass=%d, iterations=%d", pass
, iterations
);
5012 int waits_needed
= 0;
5014 for (auto *target
: all_non_exited_process_targets ())
5016 switch_to_target_no_thread (target
);
5017 update_thread_list ();
5020 /* Go through all threads looking for threads that we need
5021 to tell the target to stop. */
5022 for (thread_info
*t
: all_non_exited_threads ())
5024 /* For a single-target setting with an all-stop target,
5025 we would not even arrive here. For a multi-target
5026 setting, until GDB is able to handle a mixture of
5027 all-stop and non-stop targets, simply skip all-stop
5028 targets' threads. This should be fine due to the
5029 protection of 'check_multi_target_resumption'. */
5031 switch_to_thread_no_regs (t
);
5032 if (!target_is_non_stop_p ())
5037 /* If already stopping, don't request a stop again.
5038 We just haven't seen the notification yet. */
5039 if (!t
->stop_requested
)
5041 infrun_debug_printf (" %s executing, need stop",
5042 target_pid_to_str (t
->ptid
).c_str ());
5043 target_stop (t
->ptid
);
5044 t
->stop_requested
= 1;
5048 infrun_debug_printf (" %s executing, already stopping",
5049 target_pid_to_str (t
->ptid
).c_str ());
5052 if (t
->stop_requested
)
5057 infrun_debug_printf (" %s not executing",
5058 target_pid_to_str (t
->ptid
).c_str ());
5060 /* The thread may be not executing, but still be
5061 resumed with a pending status to process. */
5066 if (waits_needed
== 0)
5069 /* If we find new threads on the second iteration, restart
5070 over. We want to see two iterations in a row with all
5075 for (int i
= 0; i
< waits_needed
; i
++)
5077 wait_one_event event
= wait_one ();
5078 if (handle_one (event
))
5085 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
5088 handle_no_resumed (struct execution_control_state
*ecs
)
5090 if (target_can_async_p ())
5092 bool any_sync
= false;
5094 for (ui
*ui
: all_uis ())
5096 if (ui
->prompt_state
== PROMPT_BLOCKED
)
5104 /* There were no unwaited-for children left in the target, but,
5105 we're not synchronously waiting for events either. Just
5108 infrun_debug_printf ("TARGET_WAITKIND_NO_RESUMED (ignoring: bg)");
5109 prepare_to_wait (ecs
);
5114 /* Otherwise, if we were running a synchronous execution command, we
5115 may need to cancel it and give the user back the terminal.
5117 In non-stop mode, the target can't tell whether we've already
5118 consumed previous stop events, so it can end up sending us a
5119 no-resumed event like so:
5121 #0 - thread 1 is left stopped
5123 #1 - thread 2 is resumed and hits breakpoint
5124 -> TARGET_WAITKIND_STOPPED
5126 #2 - thread 3 is resumed and exits
5127 this is the last resumed thread, so
5128 -> TARGET_WAITKIND_NO_RESUMED
5130 #3 - gdb processes stop for thread 2 and decides to re-resume
5133 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
5134 thread 2 is now resumed, so the event should be ignored.
5136 IOW, if the stop for thread 2 doesn't end a foreground command,
5137 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
5138 event. But it could be that the event meant that thread 2 itself
5139 (or whatever other thread was the last resumed thread) exited.
5141 To address this we refresh the thread list and check whether we
5142 have resumed threads _now_. In the example above, this removes
5143 thread 3 from the thread list. If thread 2 was re-resumed, we
5144 ignore this event. If we find no thread resumed, then we cancel
5145 the synchronous command and show "no unwaited-for " to the
5148 inferior
*curr_inf
= current_inferior ();
5150 scoped_restore_current_thread restore_thread
;
5152 for (auto *target
: all_non_exited_process_targets ())
5154 switch_to_target_no_thread (target
);
5155 update_thread_list ();
5160 - the current target has no thread executing, and
5161 - the current inferior is native, and
5162 - the current inferior is the one which has the terminal, and
5165 then a Ctrl-C from this point on would remain stuck in the
5166 kernel, until a thread resumes and dequeues it. That would
5167 result in the GDB CLI not reacting to Ctrl-C, not able to
5168 interrupt the program. To address this, if the current inferior
5169 no longer has any thread executing, we give the terminal to some
5170 other inferior that has at least one thread executing. */
5171 bool swap_terminal
= true;
5173 /* Whether to ignore this TARGET_WAITKIND_NO_RESUMED event, or
5174 whether to report it to the user. */
5175 bool ignore_event
= false;
5177 for (thread_info
*thread
: all_non_exited_threads ())
5179 if (swap_terminal
&& thread
->executing
)
5181 if (thread
->inf
!= curr_inf
)
5183 target_terminal::ours ();
5185 switch_to_thread (thread
);
5186 target_terminal::inferior ();
5188 swap_terminal
= false;
5192 && (thread
->executing
5193 || thread
->suspend
.waitstatus_pending_p
))
5195 /* Either there were no unwaited-for children left in the
5196 target at some point, but there are now, or some target
5197 other than the eventing one has unwaited-for children
5198 left. Just ignore. */
5199 infrun_debug_printf ("TARGET_WAITKIND_NO_RESUMED "
5200 "(ignoring: found resumed)");
5202 ignore_event
= true;
5205 if (ignore_event
&& !swap_terminal
)
5211 switch_to_inferior_no_thread (curr_inf
);
5212 prepare_to_wait (ecs
);
5216 /* Go ahead and report the event. */
5220 /* Given an execution control state that has been freshly filled in by
5221 an event from the inferior, figure out what it means and take
5224 The alternatives are:
5226 1) stop_waiting and return; to really stop and return to the
5229 2) keep_going and return; to wait for the next event (set
5230 ecs->event_thread->stepping_over_breakpoint to 1 to single step
5234 handle_inferior_event (struct execution_control_state
*ecs
)
5236 /* Make sure that all temporary struct value objects that were
5237 created during the handling of the event get deleted at the
5239 scoped_value_mark free_values
;
5241 infrun_debug_printf ("%s", target_waitstatus_to_string (&ecs
->ws
).c_str ());
5243 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
5245 /* We had an event in the inferior, but we are not interested in
5246 handling it at this level. The lower layers have already
5247 done what needs to be done, if anything.
5249 One of the possible circumstances for this is when the
5250 inferior produces output for the console. The inferior has
5251 not stopped, and we are ignoring the event. Another possible
5252 circumstance is any event which the lower level knows will be
5253 reported multiple times without an intervening resume. */
5254 prepare_to_wait (ecs
);
5258 if (ecs
->ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
)
5260 prepare_to_wait (ecs
);
5264 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
5265 && handle_no_resumed (ecs
))
5268 /* Cache the last target/ptid/waitstatus. */
5269 set_last_target_status (ecs
->target
, ecs
->ptid
, ecs
->ws
);
5271 /* Always clear state belonging to the previous time we stopped. */
5272 stop_stack_dummy
= STOP_NONE
;
5274 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
5276 /* No unwaited-for children left. IOW, all resumed children
5278 stop_print_frame
= false;
5283 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
5284 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
5286 ecs
->event_thread
= find_thread_ptid (ecs
->target
, ecs
->ptid
);
5287 /* If it's a new thread, add it to the thread database. */
5288 if (ecs
->event_thread
== NULL
)
5289 ecs
->event_thread
= add_thread (ecs
->target
, ecs
->ptid
);
5291 /* Disable range stepping. If the next step request could use a
5292 range, this will be end up re-enabled then. */
5293 ecs
->event_thread
->control
.may_range_step
= 0;
5296 /* Dependent on valid ECS->EVENT_THREAD. */
5297 adjust_pc_after_break (ecs
->event_thread
, &ecs
->ws
);
5299 /* Dependent on the current PC value modified by adjust_pc_after_break. */
5300 reinit_frame_cache ();
5302 breakpoint_retire_moribund ();
5304 /* First, distinguish signals caused by the debugger from signals
5305 that have to do with the program's own actions. Note that
5306 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
5307 on the operating system version. Here we detect when a SIGILL or
5308 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
5309 something similar for SIGSEGV, since a SIGSEGV will be generated
5310 when we're trying to execute a breakpoint instruction on a
5311 non-executable stack. This happens for call dummy breakpoints
5312 for architectures like SPARC that place call dummies on the
5314 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
5315 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
5316 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
5317 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
5319 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
5321 if (breakpoint_inserted_here_p (regcache
->aspace (),
5322 regcache_read_pc (regcache
)))
5324 infrun_debug_printf ("Treating signal as SIGTRAP");
5325 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
5329 mark_non_executing_threads (ecs
->target
, ecs
->ptid
, ecs
->ws
);
5331 switch (ecs
->ws
.kind
)
5333 case TARGET_WAITKIND_LOADED
:
5335 context_switch (ecs
);
5336 /* Ignore gracefully during startup of the inferior, as it might
5337 be the shell which has just loaded some objects, otherwise
5338 add the symbols for the newly loaded objects. Also ignore at
5339 the beginning of an attach or remote session; we will query
5340 the full list of libraries once the connection is
5343 stop_kind stop_soon
= get_inferior_stop_soon (ecs
);
5344 if (stop_soon
== NO_STOP_QUIETLY
)
5346 struct regcache
*regcache
;
5348 regcache
= get_thread_regcache (ecs
->event_thread
);
5350 handle_solib_event ();
5352 ecs
->event_thread
->control
.stop_bpstat
5353 = bpstat_stop_status (regcache
->aspace (),
5354 ecs
->event_thread
->suspend
.stop_pc
,
5355 ecs
->event_thread
, &ecs
->ws
);
5357 if (handle_stop_requested (ecs
))
5360 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5362 /* A catchpoint triggered. */
5363 process_event_stop_test (ecs
);
5367 /* If requested, stop when the dynamic linker notifies
5368 gdb of events. This allows the user to get control
5369 and place breakpoints in initializer routines for
5370 dynamically loaded objects (among other things). */
5371 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5372 if (stop_on_solib_events
)
5374 /* Make sure we print "Stopped due to solib-event" in
5376 stop_print_frame
= true;
5383 /* If we are skipping through a shell, or through shared library
5384 loading that we aren't interested in, resume the program. If
5385 we're running the program normally, also resume. */
5386 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
5388 /* Loading of shared libraries might have changed breakpoint
5389 addresses. Make sure new breakpoints are inserted. */
5390 if (stop_soon
== NO_STOP_QUIETLY
)
5391 insert_breakpoints ();
5392 resume (GDB_SIGNAL_0
);
5393 prepare_to_wait (ecs
);
5397 /* But stop if we're attaching or setting up a remote
5399 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5400 || stop_soon
== STOP_QUIETLY_REMOTE
)
5402 infrun_debug_printf ("quietly stopped");
5407 internal_error (__FILE__
, __LINE__
,
5408 _("unhandled stop_soon: %d"), (int) stop_soon
);
5411 case TARGET_WAITKIND_SPURIOUS
:
5412 if (handle_stop_requested (ecs
))
5414 context_switch (ecs
);
5415 resume (GDB_SIGNAL_0
);
5416 prepare_to_wait (ecs
);
5419 case TARGET_WAITKIND_THREAD_CREATED
:
5420 if (handle_stop_requested (ecs
))
5422 context_switch (ecs
);
5423 if (!switch_back_to_stepped_thread (ecs
))
5427 case TARGET_WAITKIND_EXITED
:
5428 case TARGET_WAITKIND_SIGNALLED
:
5430 /* Depending on the system, ecs->ptid may point to a thread or
5431 to a process. On some targets, target_mourn_inferior may
5432 need to have access to the just-exited thread. That is the
5433 case of GNU/Linux's "checkpoint" support, for example.
5434 Call the switch_to_xxx routine as appropriate. */
5435 thread_info
*thr
= find_thread_ptid (ecs
->target
, ecs
->ptid
);
5437 switch_to_thread (thr
);
5440 inferior
*inf
= find_inferior_ptid (ecs
->target
, ecs
->ptid
);
5441 switch_to_inferior_no_thread (inf
);
5444 handle_vfork_child_exec_or_exit (0);
5445 target_terminal::ours (); /* Must do this before mourn anyway. */
5447 /* Clearing any previous state of convenience variables. */
5448 clear_exit_convenience_vars ();
5450 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
5452 /* Record the exit code in the convenience variable $_exitcode, so
5453 that the user can inspect this again later. */
5454 set_internalvar_integer (lookup_internalvar ("_exitcode"),
5455 (LONGEST
) ecs
->ws
.value
.integer
);
5457 /* Also record this in the inferior itself. */
5458 current_inferior ()->has_exit_code
= 1;
5459 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
5461 /* Support the --return-child-result option. */
5462 return_child_result_value
= ecs
->ws
.value
.integer
;
5464 gdb::observers::exited
.notify (ecs
->ws
.value
.integer
);
5468 struct gdbarch
*gdbarch
= current_inferior ()->gdbarch
;
5470 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
5472 /* Set the value of the internal variable $_exitsignal,
5473 which holds the signal uncaught by the inferior. */
5474 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
5475 gdbarch_gdb_signal_to_target (gdbarch
,
5476 ecs
->ws
.value
.sig
));
5480 /* We don't have access to the target's method used for
5481 converting between signal numbers (GDB's internal
5482 representation <-> target's representation).
5483 Therefore, we cannot do a good job at displaying this
5484 information to the user. It's better to just warn
5485 her about it (if infrun debugging is enabled), and
5487 infrun_debug_printf ("Cannot fill $_exitsignal with the correct "
5491 gdb::observers::signal_exited
.notify (ecs
->ws
.value
.sig
);
5494 gdb_flush (gdb_stdout
);
5495 target_mourn_inferior (inferior_ptid
);
5496 stop_print_frame
= false;
5500 case TARGET_WAITKIND_FORKED
:
5501 case TARGET_WAITKIND_VFORKED
:
5502 /* Check whether the inferior is displaced stepping. */
5504 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
5505 struct gdbarch
*gdbarch
= regcache
->arch ();
5506 inferior
*parent_inf
= find_inferior_ptid (ecs
->target
, ecs
->ptid
);
5508 /* If this is a fork (child gets its own address space copy)
5509 and some displaced step buffers were in use at the time of
5510 the fork, restore the displaced step buffer bytes in the
5513 Architectures which support displaced stepping and fork
5514 events must supply an implementation of
5515 gdbarch_displaced_step_restore_all_in_ptid. This is not
5516 enforced during gdbarch validation to support architectures
5517 which support displaced stepping but not forks. */
5518 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
5519 && gdbarch_supports_displaced_stepping (gdbarch
))
5520 gdbarch_displaced_step_restore_all_in_ptid
5521 (gdbarch
, parent_inf
, ecs
->ws
.value
.related_pid
);
5523 /* If displaced stepping is supported, and thread ecs->ptid is
5524 displaced stepping. */
5525 if (displaced_step_in_progress_thread (ecs
->event_thread
))
5527 struct regcache
*child_regcache
;
5528 CORE_ADDR parent_pc
;
5530 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
5531 indicating that the displaced stepping of syscall instruction
5532 has been done. Perform cleanup for parent process here. Note
5533 that this operation also cleans up the child process for vfork,
5534 because their pages are shared. */
5535 displaced_step_finish (ecs
->event_thread
, GDB_SIGNAL_TRAP
);
5536 /* Start a new step-over in another thread if there's one
5540 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
5541 the child's PC is also within the scratchpad. Set the child's PC
5542 to the parent's PC value, which has already been fixed up.
5543 FIXME: we use the parent's aspace here, although we're touching
5544 the child, because the child hasn't been added to the inferior
5545 list yet at this point. */
5548 = get_thread_arch_aspace_regcache (parent_inf
->process_target (),
5549 ecs
->ws
.value
.related_pid
,
5551 parent_inf
->aspace
);
5552 /* Read PC value of parent process. */
5553 parent_pc
= regcache_read_pc (regcache
);
5555 displaced_debug_printf ("write child pc from %s to %s",
5557 regcache_read_pc (child_regcache
)),
5558 paddress (gdbarch
, parent_pc
));
5560 regcache_write_pc (child_regcache
, parent_pc
);
5564 context_switch (ecs
);
5566 /* Immediately detach breakpoints from the child before there's
5567 any chance of letting the user delete breakpoints from the
5568 breakpoint lists. If we don't do this early, it's easy to
5569 leave left over traps in the child, vis: "break foo; catch
5570 fork; c; <fork>; del; c; <child calls foo>". We only follow
5571 the fork on the last `continue', and by that time the
5572 breakpoint at "foo" is long gone from the breakpoint table.
5573 If we vforked, then we don't need to unpatch here, since both
5574 parent and child are sharing the same memory pages; we'll
5575 need to unpatch at follow/detach time instead to be certain
5576 that new breakpoints added between catchpoint hit time and
5577 vfork follow are detached. */
5578 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
5580 /* This won't actually modify the breakpoint list, but will
5581 physically remove the breakpoints from the child. */
5582 detach_breakpoints (ecs
->ws
.value
.related_pid
);
5585 delete_just_stopped_threads_single_step_breakpoints ();
5587 /* In case the event is caught by a catchpoint, remember that
5588 the event is to be followed at the next resume of the thread,
5589 and not immediately. */
5590 ecs
->event_thread
->pending_follow
= ecs
->ws
;
5592 ecs
->event_thread
->suspend
.stop_pc
5593 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
5595 ecs
->event_thread
->control
.stop_bpstat
5596 = bpstat_stop_status (get_current_regcache ()->aspace (),
5597 ecs
->event_thread
->suspend
.stop_pc
,
5598 ecs
->event_thread
, &ecs
->ws
);
5600 if (handle_stop_requested (ecs
))
5603 /* If no catchpoint triggered for this, then keep going. Note
5604 that we're interested in knowing the bpstat actually causes a
5605 stop, not just if it may explain the signal. Software
5606 watchpoints, for example, always appear in the bpstat. */
5607 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5610 = (follow_fork_mode_string
== follow_fork_mode_child
);
5612 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5614 process_stratum_target
*targ
5615 = ecs
->event_thread
->inf
->process_target ();
5617 bool should_resume
= follow_fork ();
5619 /* Note that one of these may be an invalid pointer,
5620 depending on detach_fork. */
5621 thread_info
*parent
= ecs
->event_thread
;
5623 = find_thread_ptid (targ
, ecs
->ws
.value
.related_pid
);
5625 /* At this point, the parent is marked running, and the
5626 child is marked stopped. */
5628 /* If not resuming the parent, mark it stopped. */
5629 if (follow_child
&& !detach_fork
&& !non_stop
&& !sched_multi
)
5630 parent
->set_running (false);
5632 /* If resuming the child, mark it running. */
5633 if (follow_child
|| (!detach_fork
&& (non_stop
|| sched_multi
)))
5634 child
->set_running (true);
5636 /* In non-stop mode, also resume the other branch. */
5637 if (!detach_fork
&& (non_stop
5638 || (sched_multi
&& target_is_non_stop_p ())))
5641 switch_to_thread (parent
);
5643 switch_to_thread (child
);
5645 ecs
->event_thread
= inferior_thread ();
5646 ecs
->ptid
= inferior_ptid
;
5651 switch_to_thread (child
);
5653 switch_to_thread (parent
);
5655 ecs
->event_thread
= inferior_thread ();
5656 ecs
->ptid
= inferior_ptid
;
5664 process_event_stop_test (ecs
);
5667 case TARGET_WAITKIND_VFORK_DONE
:
5668 /* Done with the shared memory region. Re-insert breakpoints in
5669 the parent, and keep going. */
5671 context_switch (ecs
);
5673 current_inferior ()->waiting_for_vfork_done
= 0;
5674 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
5676 if (handle_stop_requested (ecs
))
5679 /* This also takes care of reinserting breakpoints in the
5680 previously locked inferior. */
5684 case TARGET_WAITKIND_EXECD
:
5686 /* Note we can't read registers yet (the stop_pc), because we
5687 don't yet know the inferior's post-exec architecture.
5688 'stop_pc' is explicitly read below instead. */
5689 switch_to_thread_no_regs (ecs
->event_thread
);
5691 /* Do whatever is necessary to the parent branch of the vfork. */
5692 handle_vfork_child_exec_or_exit (1);
5694 /* This causes the eventpoints and symbol table to be reset.
5695 Must do this now, before trying to determine whether to
5697 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
5699 /* In follow_exec we may have deleted the original thread and
5700 created a new one. Make sure that the event thread is the
5701 execd thread for that case (this is a nop otherwise). */
5702 ecs
->event_thread
= inferior_thread ();
5704 ecs
->event_thread
->suspend
.stop_pc
5705 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
5707 ecs
->event_thread
->control
.stop_bpstat
5708 = bpstat_stop_status (get_current_regcache ()->aspace (),
5709 ecs
->event_thread
->suspend
.stop_pc
,
5710 ecs
->event_thread
, &ecs
->ws
);
5712 /* Note that this may be referenced from inside
5713 bpstat_stop_status above, through inferior_has_execd. */
5714 xfree (ecs
->ws
.value
.execd_pathname
);
5715 ecs
->ws
.value
.execd_pathname
= NULL
;
5717 if (handle_stop_requested (ecs
))
5720 /* If no catchpoint triggered for this, then keep going. */
5721 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5723 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5727 process_event_stop_test (ecs
);
5730 /* Be careful not to try to gather much state about a thread
5731 that's in a syscall. It's frequently a losing proposition. */
5732 case TARGET_WAITKIND_SYSCALL_ENTRY
:
5733 /* Getting the current syscall number. */
5734 if (handle_syscall_event (ecs
) == 0)
5735 process_event_stop_test (ecs
);
5738 /* Before examining the threads further, step this thread to
5739 get it entirely out of the syscall. (We get notice of the
5740 event when the thread is just on the verge of exiting a
5741 syscall. Stepping one instruction seems to get it back
5743 case TARGET_WAITKIND_SYSCALL_RETURN
:
5744 if (handle_syscall_event (ecs
) == 0)
5745 process_event_stop_test (ecs
);
5748 case TARGET_WAITKIND_STOPPED
:
5749 handle_signal_stop (ecs
);
5752 case TARGET_WAITKIND_NO_HISTORY
:
5753 /* Reverse execution: target ran out of history info. */
5755 /* Switch to the stopped thread. */
5756 context_switch (ecs
);
5757 infrun_debug_printf ("stopped");
5759 delete_just_stopped_threads_single_step_breakpoints ();
5760 ecs
->event_thread
->suspend
.stop_pc
5761 = regcache_read_pc (get_thread_regcache (inferior_thread ()));
5763 if (handle_stop_requested (ecs
))
5766 gdb::observers::no_history
.notify ();
5772 /* Restart threads back to what they were trying to do back when we
5773 paused them for an in-line step-over. The EVENT_THREAD thread is
5777 restart_threads (struct thread_info
*event_thread
)
5779 /* In case the instruction just stepped spawned a new thread. */
5780 update_thread_list ();
5782 for (thread_info
*tp
: all_non_exited_threads ())
5784 if (tp
->inf
->detaching
)
5786 infrun_debug_printf ("restart threads: [%s] inferior detaching",
5787 target_pid_to_str (tp
->ptid
).c_str ());
5791 switch_to_thread_no_regs (tp
);
5793 if (tp
== event_thread
)
5795 infrun_debug_printf ("restart threads: [%s] is event thread",
5796 target_pid_to_str (tp
->ptid
).c_str ());
5800 if (!(tp
->state
== THREAD_RUNNING
|| tp
->control
.in_infcall
))
5802 infrun_debug_printf ("restart threads: [%s] not meant to be running",
5803 target_pid_to_str (tp
->ptid
).c_str ());
5809 infrun_debug_printf ("restart threads: [%s] resumed",
5810 target_pid_to_str (tp
->ptid
).c_str ());
5811 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
5815 if (thread_is_in_step_over_chain (tp
))
5817 infrun_debug_printf ("restart threads: [%s] needs step-over",
5818 target_pid_to_str (tp
->ptid
).c_str ());
5819 gdb_assert (!tp
->resumed
);
5824 if (tp
->suspend
.waitstatus_pending_p
)
5826 infrun_debug_printf ("restart threads: [%s] has pending status",
5827 target_pid_to_str (tp
->ptid
).c_str ());
5832 gdb_assert (!tp
->stop_requested
);
5834 /* If some thread needs to start a step-over at this point, it
5835 should still be in the step-over queue, and thus skipped
5837 if (thread_still_needs_step_over (tp
))
5839 internal_error (__FILE__
, __LINE__
,
5840 "thread [%s] needs a step-over, but not in "
5841 "step-over queue\n",
5842 target_pid_to_str (tp
->ptid
).c_str ());
5845 if (currently_stepping (tp
))
5847 infrun_debug_printf ("restart threads: [%s] was stepping",
5848 target_pid_to_str (tp
->ptid
).c_str ());
5849 keep_going_stepped_thread (tp
);
5853 struct execution_control_state ecss
;
5854 struct execution_control_state
*ecs
= &ecss
;
5856 infrun_debug_printf ("restart threads: [%s] continuing",
5857 target_pid_to_str (tp
->ptid
).c_str ());
5858 reset_ecs (ecs
, tp
);
5859 switch_to_thread (tp
);
5860 keep_going_pass_signal (ecs
);
5865 /* Callback for iterate_over_threads. Find a resumed thread that has
5866 a pending waitstatus. */
5869 resumed_thread_with_pending_status (struct thread_info
*tp
,
5873 && tp
->suspend
.waitstatus_pending_p
);
5876 /* Called when we get an event that may finish an in-line or
5877 out-of-line (displaced stepping) step-over started previously.
5878 Return true if the event is processed and we should go back to the
5879 event loop; false if the caller should continue processing the
5883 finish_step_over (struct execution_control_state
*ecs
)
5885 displaced_step_finish (ecs
->event_thread
,
5886 ecs
->event_thread
->suspend
.stop_signal
);
5888 bool had_step_over_info
= step_over_info_valid_p ();
5890 if (had_step_over_info
)
5892 /* If we're stepping over a breakpoint with all threads locked,
5893 then only the thread that was stepped should be reporting
5895 gdb_assert (ecs
->event_thread
->control
.trap_expected
);
5897 clear_step_over_info ();
5900 if (!target_is_non_stop_p ())
5903 /* Start a new step-over in another thread if there's one that
5907 /* If we were stepping over a breakpoint before, and haven't started
5908 a new in-line step-over sequence, then restart all other threads
5909 (except the event thread). We can't do this in all-stop, as then
5910 e.g., we wouldn't be able to issue any other remote packet until
5911 these other threads stop. */
5912 if (had_step_over_info
&& !step_over_info_valid_p ())
5914 struct thread_info
*pending
;
5916 /* If we only have threads with pending statuses, the restart
5917 below won't restart any thread and so nothing re-inserts the
5918 breakpoint we just stepped over. But we need it inserted
5919 when we later process the pending events, otherwise if
5920 another thread has a pending event for this breakpoint too,
5921 we'd discard its event (because the breakpoint that
5922 originally caused the event was no longer inserted). */
5923 context_switch (ecs
);
5924 insert_breakpoints ();
5926 restart_threads (ecs
->event_thread
);
5928 /* If we have events pending, go through handle_inferior_event
5929 again, picking up a pending event at random. This avoids
5930 thread starvation. */
5932 /* But not if we just stepped over a watchpoint in order to let
5933 the instruction execute so we can evaluate its expression.
5934 The set of watchpoints that triggered is recorded in the
5935 breakpoint objects themselves (see bp->watchpoint_triggered).
5936 If we processed another event first, that other event could
5937 clobber this info. */
5938 if (ecs
->event_thread
->stepping_over_watchpoint
)
5941 pending
= iterate_over_threads (resumed_thread_with_pending_status
,
5943 if (pending
!= NULL
)
5945 struct thread_info
*tp
= ecs
->event_thread
;
5946 struct regcache
*regcache
;
5948 infrun_debug_printf ("found resumed threads with "
5949 "pending events, saving status");
5951 gdb_assert (pending
!= tp
);
5953 /* Record the event thread's event for later. */
5954 save_waitstatus (tp
, &ecs
->ws
);
5955 /* This was cleared early, by handle_inferior_event. Set it
5956 so this pending event is considered by
5960 gdb_assert (!tp
->executing
);
5962 regcache
= get_thread_regcache (tp
);
5963 tp
->suspend
.stop_pc
= regcache_read_pc (regcache
);
5965 infrun_debug_printf ("saved stop_pc=%s for %s "
5966 "(currently_stepping=%d)",
5967 paddress (target_gdbarch (),
5968 tp
->suspend
.stop_pc
),
5969 target_pid_to_str (tp
->ptid
).c_str (),
5970 currently_stepping (tp
));
5972 /* This in-line step-over finished; clear this so we won't
5973 start a new one. This is what handle_signal_stop would
5974 do, if we returned false. */
5975 tp
->stepping_over_breakpoint
= 0;
5977 /* Wake up the event loop again. */
5978 mark_async_event_handler (infrun_async_inferior_event_token
);
5980 prepare_to_wait (ecs
);
5988 /* Come here when the program has stopped with a signal. */
5991 handle_signal_stop (struct execution_control_state
*ecs
)
5993 struct frame_info
*frame
;
5994 struct gdbarch
*gdbarch
;
5995 int stopped_by_watchpoint
;
5996 enum stop_kind stop_soon
;
5999 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
6001 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
6003 /* Do we need to clean up the state of a thread that has
6004 completed a displaced single-step? (Doing so usually affects
6005 the PC, so do it here, before we set stop_pc.) */
6006 if (finish_step_over (ecs
))
6009 /* If we either finished a single-step or hit a breakpoint, but
6010 the user wanted this thread to be stopped, pretend we got a
6011 SIG0 (generic unsignaled stop). */
6012 if (ecs
->event_thread
->stop_requested
6013 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
6014 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6016 ecs
->event_thread
->suspend
.stop_pc
6017 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
6019 context_switch (ecs
);
6021 if (deprecated_context_hook
)
6022 deprecated_context_hook (ecs
->event_thread
->global_num
);
6026 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
6027 struct gdbarch
*reg_gdbarch
= regcache
->arch ();
6029 infrun_debug_printf ("stop_pc=%s",
6030 paddress (reg_gdbarch
,
6031 ecs
->event_thread
->suspend
.stop_pc
));
6032 if (target_stopped_by_watchpoint ())
6036 infrun_debug_printf ("stopped by watchpoint");
6038 if (target_stopped_data_address (current_inferior ()->top_target (),
6040 infrun_debug_printf ("stopped data address=%s",
6041 paddress (reg_gdbarch
, addr
));
6043 infrun_debug_printf ("(no data address available)");
6047 /* This is originated from start_remote(), start_inferior() and
6048 shared libraries hook functions. */
6049 stop_soon
= get_inferior_stop_soon (ecs
);
6050 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
6052 infrun_debug_printf ("quietly stopped");
6053 stop_print_frame
= true;
6058 /* This originates from attach_command(). We need to overwrite
6059 the stop_signal here, because some kernels don't ignore a
6060 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
6061 See more comments in inferior.h. On the other hand, if we
6062 get a non-SIGSTOP, report it to the user - assume the backend
6063 will handle the SIGSTOP if it should show up later.
6065 Also consider that the attach is complete when we see a
6066 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
6067 target extended-remote report it instead of a SIGSTOP
6068 (e.g. gdbserver). We already rely on SIGTRAP being our
6069 signal, so this is no exception.
6071 Also consider that the attach is complete when we see a
6072 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
6073 the target to stop all threads of the inferior, in case the
6074 low level attach operation doesn't stop them implicitly. If
6075 they weren't stopped implicitly, then the stub will report a
6076 GDB_SIGNAL_0, meaning: stopped for no particular reason
6077 other than GDB's request. */
6078 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
6079 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
6080 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6081 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
6083 stop_print_frame
= true;
6085 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6089 /* At this point, get hold of the now-current thread's frame. */
6090 frame
= get_current_frame ();
6091 gdbarch
= get_frame_arch (frame
);
6093 /* Pull the single step breakpoints out of the target. */
6094 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
6096 struct regcache
*regcache
;
6099 regcache
= get_thread_regcache (ecs
->event_thread
);
6100 const address_space
*aspace
= regcache
->aspace ();
6102 pc
= regcache_read_pc (regcache
);
6104 /* However, before doing so, if this single-step breakpoint was
6105 actually for another thread, set this thread up for moving
6107 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
6110 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
6112 infrun_debug_printf ("[%s] hit another thread's single-step "
6114 target_pid_to_str (ecs
->ptid
).c_str ());
6115 ecs
->hit_singlestep_breakpoint
= 1;
6120 infrun_debug_printf ("[%s] hit its single-step breakpoint",
6121 target_pid_to_str (ecs
->ptid
).c_str ());
6124 delete_just_stopped_threads_single_step_breakpoints ();
6126 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6127 && ecs
->event_thread
->control
.trap_expected
6128 && ecs
->event_thread
->stepping_over_watchpoint
)
6129 stopped_by_watchpoint
= 0;
6131 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
6133 /* If necessary, step over this watchpoint. We'll be back to display
6135 if (stopped_by_watchpoint
6136 && (target_have_steppable_watchpoint ()
6137 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
6139 /* At this point, we are stopped at an instruction which has
6140 attempted to write to a piece of memory under control of
6141 a watchpoint. The instruction hasn't actually executed
6142 yet. If we were to evaluate the watchpoint expression
6143 now, we would get the old value, and therefore no change
6144 would seem to have occurred.
6146 In order to make watchpoints work `right', we really need
6147 to complete the memory write, and then evaluate the
6148 watchpoint expression. We do this by single-stepping the
6151 It may not be necessary to disable the watchpoint to step over
6152 it. For example, the PA can (with some kernel cooperation)
6153 single step over a watchpoint without disabling the watchpoint.
6155 It is far more common to need to disable a watchpoint to step
6156 the inferior over it. If we have non-steppable watchpoints,
6157 we must disable the current watchpoint; it's simplest to
6158 disable all watchpoints.
6160 Any breakpoint at PC must also be stepped over -- if there's
6161 one, it will have already triggered before the watchpoint
6162 triggered, and we either already reported it to the user, or
6163 it didn't cause a stop and we called keep_going. In either
6164 case, if there was a breakpoint at PC, we must be trying to
6166 ecs
->event_thread
->stepping_over_watchpoint
= 1;
6171 ecs
->event_thread
->stepping_over_breakpoint
= 0;
6172 ecs
->event_thread
->stepping_over_watchpoint
= 0;
6173 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
6174 ecs
->event_thread
->control
.stop_step
= 0;
6175 stop_print_frame
= true;
6176 stopped_by_random_signal
= 0;
6177 bpstat stop_chain
= NULL
;
6179 /* Hide inlined functions starting here, unless we just performed stepi or
6180 nexti. After stepi and nexti, always show the innermost frame (not any
6181 inline function call sites). */
6182 if (ecs
->event_thread
->control
.step_range_end
!= 1)
6184 const address_space
*aspace
6185 = get_thread_regcache (ecs
->event_thread
)->aspace ();
6187 /* skip_inline_frames is expensive, so we avoid it if we can
6188 determine that the address is one where functions cannot have
6189 been inlined. This improves performance with inferiors that
6190 load a lot of shared libraries, because the solib event
6191 breakpoint is defined as the address of a function (i.e. not
6192 inline). Note that we have to check the previous PC as well
6193 as the current one to catch cases when we have just
6194 single-stepped off a breakpoint prior to reinstating it.
6195 Note that we're assuming that the code we single-step to is
6196 not inline, but that's not definitive: there's nothing
6197 preventing the event breakpoint function from containing
6198 inlined code, and the single-step ending up there. If the
6199 user had set a breakpoint on that inlined code, the missing
6200 skip_inline_frames call would break things. Fortunately
6201 that's an extremely unlikely scenario. */
6202 if (!pc_at_non_inline_function (aspace
,
6203 ecs
->event_thread
->suspend
.stop_pc
,
6205 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6206 && ecs
->event_thread
->control
.trap_expected
6207 && pc_at_non_inline_function (aspace
,
6208 ecs
->event_thread
->prev_pc
,
6211 stop_chain
= build_bpstat_chain (aspace
,
6212 ecs
->event_thread
->suspend
.stop_pc
,
6214 skip_inline_frames (ecs
->event_thread
, stop_chain
);
6216 /* Re-fetch current thread's frame in case that invalidated
6218 frame
= get_current_frame ();
6219 gdbarch
= get_frame_arch (frame
);
6223 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6224 && ecs
->event_thread
->control
.trap_expected
6225 && gdbarch_single_step_through_delay_p (gdbarch
)
6226 && currently_stepping (ecs
->event_thread
))
6228 /* We're trying to step off a breakpoint. Turns out that we're
6229 also on an instruction that needs to be stepped multiple
6230 times before it's been fully executing. E.g., architectures
6231 with a delay slot. It needs to be stepped twice, once for
6232 the instruction and once for the delay slot. */
6233 int step_through_delay
6234 = gdbarch_single_step_through_delay (gdbarch
, frame
);
6236 if (step_through_delay
)
6237 infrun_debug_printf ("step through delay");
6239 if (ecs
->event_thread
->control
.step_range_end
== 0
6240 && step_through_delay
)
6242 /* The user issued a continue when stopped at a breakpoint.
6243 Set up for another trap and get out of here. */
6244 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6248 else if (step_through_delay
)
6250 /* The user issued a step when stopped at a breakpoint.
6251 Maybe we should stop, maybe we should not - the delay
6252 slot *might* correspond to a line of source. In any
6253 case, don't decide that here, just set
6254 ecs->stepping_over_breakpoint, making sure we
6255 single-step again before breakpoints are re-inserted. */
6256 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6260 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
6261 handles this event. */
6262 ecs
->event_thread
->control
.stop_bpstat
6263 = bpstat_stop_status (get_current_regcache ()->aspace (),
6264 ecs
->event_thread
->suspend
.stop_pc
,
6265 ecs
->event_thread
, &ecs
->ws
, stop_chain
);
6267 /* Following in case break condition called a
6269 stop_print_frame
= true;
6271 /* This is where we handle "moribund" watchpoints. Unlike
6272 software breakpoints traps, hardware watchpoint traps are
6273 always distinguishable from random traps. If no high-level
6274 watchpoint is associated with the reported stop data address
6275 anymore, then the bpstat does not explain the signal ---
6276 simply make sure to ignore it if `stopped_by_watchpoint' is
6279 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6280 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
6282 && stopped_by_watchpoint
)
6284 infrun_debug_printf ("no user watchpoint explains watchpoint SIGTRAP, "
6288 /* NOTE: cagney/2003-03-29: These checks for a random signal
6289 at one stage in the past included checks for an inferior
6290 function call's call dummy's return breakpoint. The original
6291 comment, that went with the test, read:
6293 ``End of a stack dummy. Some systems (e.g. Sony news) give
6294 another signal besides SIGTRAP, so check here as well as
6297 If someone ever tries to get call dummys on a
6298 non-executable stack to work (where the target would stop
6299 with something like a SIGSEGV), then those tests might need
6300 to be re-instated. Given, however, that the tests were only
6301 enabled when momentary breakpoints were not being used, I
6302 suspect that it won't be the case.
6304 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
6305 be necessary for call dummies on a non-executable stack on
6308 /* See if the breakpoints module can explain the signal. */
6310 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
6311 ecs
->event_thread
->suspend
.stop_signal
);
6313 /* Maybe this was a trap for a software breakpoint that has since
6315 if (random_signal
&& target_stopped_by_sw_breakpoint ())
6317 if (gdbarch_program_breakpoint_here_p (gdbarch
,
6318 ecs
->event_thread
->suspend
.stop_pc
))
6320 struct regcache
*regcache
;
6323 /* Re-adjust PC to what the program would see if GDB was not
6325 regcache
= get_thread_regcache (ecs
->event_thread
);
6326 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
6329 gdb::optional
<scoped_restore_tmpl
<int>>
6330 restore_operation_disable
;
6332 if (record_full_is_used ())
6333 restore_operation_disable
.emplace
6334 (record_full_gdb_operation_disable_set ());
6336 regcache_write_pc (regcache
,
6337 ecs
->event_thread
->suspend
.stop_pc
+ decr_pc
);
6342 /* A delayed software breakpoint event. Ignore the trap. */
6343 infrun_debug_printf ("delayed software breakpoint trap, ignoring");
6348 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
6349 has since been removed. */
6350 if (random_signal
&& target_stopped_by_hw_breakpoint ())
6352 /* A delayed hardware breakpoint event. Ignore the trap. */
6353 infrun_debug_printf ("delayed hardware breakpoint/watchpoint "
6358 /* If not, perhaps stepping/nexting can. */
6360 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
6361 && currently_stepping (ecs
->event_thread
));
6363 /* Perhaps the thread hit a single-step breakpoint of _another_
6364 thread. Single-step breakpoints are transparent to the
6365 breakpoints module. */
6367 random_signal
= !ecs
->hit_singlestep_breakpoint
;
6369 /* No? Perhaps we got a moribund watchpoint. */
6371 random_signal
= !stopped_by_watchpoint
;
6373 /* Always stop if the user explicitly requested this thread to
6375 if (ecs
->event_thread
->stop_requested
)
6378 infrun_debug_printf ("user-requested stop");
6381 /* For the program's own signals, act according to
6382 the signal handling tables. */
6386 /* Signal not for debugging purposes. */
6387 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
6389 infrun_debug_printf ("random signal (%s)",
6390 gdb_signal_to_symbol_string (stop_signal
));
6392 stopped_by_random_signal
= 1;
6394 /* Always stop on signals if we're either just gaining control
6395 of the program, or the user explicitly requested this thread
6396 to remain stopped. */
6397 if (stop_soon
!= NO_STOP_QUIETLY
6398 || ecs
->event_thread
->stop_requested
6399 || signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
))
6405 /* Notify observers the signal has "handle print" set. Note we
6406 returned early above if stopping; normal_stop handles the
6407 printing in that case. */
6408 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
6410 /* The signal table tells us to print about this signal. */
6411 target_terminal::ours_for_output ();
6412 gdb::observers::signal_received
.notify (ecs
->event_thread
->suspend
.stop_signal
);
6413 target_terminal::inferior ();
6416 /* Clear the signal if it should not be passed. */
6417 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
6418 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6420 if (ecs
->event_thread
->prev_pc
== ecs
->event_thread
->suspend
.stop_pc
6421 && ecs
->event_thread
->control
.trap_expected
6422 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6424 /* We were just starting a new sequence, attempting to
6425 single-step off of a breakpoint and expecting a SIGTRAP.
6426 Instead this signal arrives. This signal will take us out
6427 of the stepping range so GDB needs to remember to, when
6428 the signal handler returns, resume stepping off that
6430 /* To simplify things, "continue" is forced to use the same
6431 code paths as single-step - set a breakpoint at the
6432 signal return address and then, once hit, step off that
6434 infrun_debug_printf ("signal arrived while stepping over breakpoint");
6436 insert_hp_step_resume_breakpoint_at_frame (frame
);
6437 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6438 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6439 ecs
->event_thread
->control
.trap_expected
= 0;
6441 /* If we were nexting/stepping some other thread, switch to
6442 it, so that we don't continue it, losing control. */
6443 if (!switch_back_to_stepped_thread (ecs
))
6448 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
6449 && (pc_in_thread_step_range (ecs
->event_thread
->suspend
.stop_pc
,
6451 || ecs
->event_thread
->control
.step_range_end
== 1)
6452 && frame_id_eq (get_stack_frame_id (frame
),
6453 ecs
->event_thread
->control
.step_stack_frame_id
)
6454 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
6456 /* The inferior is about to take a signal that will take it
6457 out of the single step range. Set a breakpoint at the
6458 current PC (which is presumably where the signal handler
6459 will eventually return) and then allow the inferior to
6462 Note that this is only needed for a signal delivered
6463 while in the single-step range. Nested signals aren't a
6464 problem as they eventually all return. */
6465 infrun_debug_printf ("signal may take us out of single-step range");
6467 clear_step_over_info ();
6468 insert_hp_step_resume_breakpoint_at_frame (frame
);
6469 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
6470 /* Reset trap_expected to ensure breakpoints are re-inserted. */
6471 ecs
->event_thread
->control
.trap_expected
= 0;
6476 /* Note: step_resume_breakpoint may be non-NULL. This occurs
6477 when either there's a nested signal, or when there's a
6478 pending signal enabled just as the signal handler returns
6479 (leaving the inferior at the step-resume-breakpoint without
6480 actually executing it). Either way continue until the
6481 breakpoint is really hit. */
6483 if (!switch_back_to_stepped_thread (ecs
))
6485 infrun_debug_printf ("random signal, keep going");
6492 process_event_stop_test (ecs
);
6495 /* Come here when we've got some debug event / signal we can explain
6496 (IOW, not a random signal), and test whether it should cause a
6497 stop, or whether we should resume the inferior (transparently).
6498 E.g., could be a breakpoint whose condition evaluates false; we
6499 could be still stepping within the line; etc. */
6502 process_event_stop_test (struct execution_control_state
*ecs
)
6504 struct symtab_and_line stop_pc_sal
;
6505 struct frame_info
*frame
;
6506 struct gdbarch
*gdbarch
;
6507 CORE_ADDR jmp_buf_pc
;
6508 struct bpstat_what what
;
6510 /* Handle cases caused by hitting a breakpoint. */
6512 frame
= get_current_frame ();
6513 gdbarch
= get_frame_arch (frame
);
6515 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
6517 if (what
.call_dummy
)
6519 stop_stack_dummy
= what
.call_dummy
;
6522 /* A few breakpoint types have callbacks associated (e.g.,
6523 bp_jit_event). Run them now. */
6524 bpstat_run_callbacks (ecs
->event_thread
->control
.stop_bpstat
);
6526 /* If we hit an internal event that triggers symbol changes, the
6527 current frame will be invalidated within bpstat_what (e.g., if we
6528 hit an internal solib event). Re-fetch it. */
6529 frame
= get_current_frame ();
6530 gdbarch
= get_frame_arch (frame
);
6532 switch (what
.main_action
)
6534 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
6535 /* If we hit the breakpoint at longjmp while stepping, we
6536 install a momentary breakpoint at the target of the
6539 infrun_debug_printf ("BPSTAT_WHAT_SET_LONGJMP_RESUME");
6541 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6543 if (what
.is_longjmp
)
6545 struct value
*arg_value
;
6547 /* If we set the longjmp breakpoint via a SystemTap probe,
6548 then use it to extract the arguments. The destination PC
6549 is the third argument to the probe. */
6550 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
6553 jmp_buf_pc
= value_as_address (arg_value
);
6554 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
6556 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
6557 || !gdbarch_get_longjmp_target (gdbarch
,
6558 frame
, &jmp_buf_pc
))
6560 infrun_debug_printf ("BPSTAT_WHAT_SET_LONGJMP_RESUME "
6561 "(!gdbarch_get_longjmp_target)");
6566 /* Insert a breakpoint at resume address. */
6567 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
6570 check_exception_resume (ecs
, frame
);
6574 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
6576 struct frame_info
*init_frame
;
6578 /* There are several cases to consider.
6580 1. The initiating frame no longer exists. In this case we
6581 must stop, because the exception or longjmp has gone too
6584 2. The initiating frame exists, and is the same as the
6585 current frame. We stop, because the exception or longjmp
6588 3. The initiating frame exists and is different from the
6589 current frame. This means the exception or longjmp has
6590 been caught beneath the initiating frame, so keep going.
6592 4. longjmp breakpoint has been placed just to protect
6593 against stale dummy frames and user is not interested in
6594 stopping around longjmps. */
6596 infrun_debug_printf ("BPSTAT_WHAT_CLEAR_LONGJMP_RESUME");
6598 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
6600 delete_exception_resume_breakpoint (ecs
->event_thread
);
6602 if (what
.is_longjmp
)
6604 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
6606 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
6614 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
6618 struct frame_id current_id
6619 = get_frame_id (get_current_frame ());
6620 if (frame_id_eq (current_id
,
6621 ecs
->event_thread
->initiating_frame
))
6623 /* Case 2. Fall through. */
6633 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6635 delete_step_resume_breakpoint (ecs
->event_thread
);
6637 end_stepping_range (ecs
);
6641 case BPSTAT_WHAT_SINGLE
:
6642 infrun_debug_printf ("BPSTAT_WHAT_SINGLE");
6643 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6644 /* Still need to check other stuff, at least the case where we
6645 are stepping and step out of the right range. */
6648 case BPSTAT_WHAT_STEP_RESUME
:
6649 infrun_debug_printf ("BPSTAT_WHAT_STEP_RESUME");
6651 delete_step_resume_breakpoint (ecs
->event_thread
);
6652 if (ecs
->event_thread
->control
.proceed_to_finish
6653 && execution_direction
== EXEC_REVERSE
)
6655 struct thread_info
*tp
= ecs
->event_thread
;
6657 /* We are finishing a function in reverse, and just hit the
6658 step-resume breakpoint at the start address of the
6659 function, and we're almost there -- just need to back up
6660 by one more single-step, which should take us back to the
6662 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
6666 fill_in_stop_func (gdbarch
, ecs
);
6667 if (ecs
->event_thread
->suspend
.stop_pc
== ecs
->stop_func_start
6668 && execution_direction
== EXEC_REVERSE
)
6670 /* We are stepping over a function call in reverse, and just
6671 hit the step-resume breakpoint at the start address of
6672 the function. Go back to single-stepping, which should
6673 take us back to the function call. */
6674 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6680 case BPSTAT_WHAT_STOP_NOISY
:
6681 infrun_debug_printf ("BPSTAT_WHAT_STOP_NOISY");
6682 stop_print_frame
= true;
6684 /* Assume the thread stopped for a breakpoint. We'll still check
6685 whether a/the breakpoint is there when the thread is next
6687 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6692 case BPSTAT_WHAT_STOP_SILENT
:
6693 infrun_debug_printf ("BPSTAT_WHAT_STOP_SILENT");
6694 stop_print_frame
= false;
6696 /* Assume the thread stopped for a breakpoint. We'll still check
6697 whether a/the breakpoint is there when the thread is next
6699 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6703 case BPSTAT_WHAT_HP_STEP_RESUME
:
6704 infrun_debug_printf ("BPSTAT_WHAT_HP_STEP_RESUME");
6706 delete_step_resume_breakpoint (ecs
->event_thread
);
6707 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
6709 /* Back when the step-resume breakpoint was inserted, we
6710 were trying to single-step off a breakpoint. Go back to
6712 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6713 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6719 case BPSTAT_WHAT_KEEP_CHECKING
:
6723 /* If we stepped a permanent breakpoint and we had a high priority
6724 step-resume breakpoint for the address we stepped, but we didn't
6725 hit it, then we must have stepped into the signal handler. The
6726 step-resume was only necessary to catch the case of _not_
6727 stepping into the handler, so delete it, and fall through to
6728 checking whether the step finished. */
6729 if (ecs
->event_thread
->stepped_breakpoint
)
6731 struct breakpoint
*sr_bp
6732 = ecs
->event_thread
->control
.step_resume_breakpoint
;
6735 && sr_bp
->loc
->permanent
6736 && sr_bp
->type
== bp_hp_step_resume
6737 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
6739 infrun_debug_printf ("stepped permanent breakpoint, stopped in handler");
6740 delete_step_resume_breakpoint (ecs
->event_thread
);
6741 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6745 /* We come here if we hit a breakpoint but should not stop for it.
6746 Possibly we also were stepping and should stop for that. So fall
6747 through and test for stepping. But, if not stepping, do not
6750 /* In all-stop mode, if we're currently stepping but have stopped in
6751 some other thread, we need to switch back to the stepped thread. */
6752 if (switch_back_to_stepped_thread (ecs
))
6755 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
6757 infrun_debug_printf ("step-resume breakpoint is inserted");
6759 /* Having a step-resume breakpoint overrides anything
6760 else having to do with stepping commands until
6761 that breakpoint is reached. */
6766 if (ecs
->event_thread
->control
.step_range_end
== 0)
6768 infrun_debug_printf ("no stepping, continue");
6769 /* Likewise if we aren't even stepping. */
6774 /* Re-fetch current thread's frame in case the code above caused
6775 the frame cache to be re-initialized, making our FRAME variable
6776 a dangling pointer. */
6777 frame
= get_current_frame ();
6778 gdbarch
= get_frame_arch (frame
);
6779 fill_in_stop_func (gdbarch
, ecs
);
6781 /* If stepping through a line, keep going if still within it.
6783 Note that step_range_end is the address of the first instruction
6784 beyond the step range, and NOT the address of the last instruction
6787 Note also that during reverse execution, we may be stepping
6788 through a function epilogue and therefore must detect when
6789 the current-frame changes in the middle of a line. */
6791 if (pc_in_thread_step_range (ecs
->event_thread
->suspend
.stop_pc
,
6793 && (execution_direction
!= EXEC_REVERSE
6794 || frame_id_eq (get_frame_id (frame
),
6795 ecs
->event_thread
->control
.step_frame_id
)))
6798 ("stepping inside range [%s-%s]",
6799 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
6800 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
6802 /* Tentatively re-enable range stepping; `resume' disables it if
6803 necessary (e.g., if we're stepping over a breakpoint or we
6804 have software watchpoints). */
6805 ecs
->event_thread
->control
.may_range_step
= 1;
6807 /* When stepping backward, stop at beginning of line range
6808 (unless it's the function entry point, in which case
6809 keep going back to the call point). */
6810 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6811 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
6812 && stop_pc
!= ecs
->stop_func_start
6813 && execution_direction
== EXEC_REVERSE
)
6814 end_stepping_range (ecs
);
6821 /* We stepped out of the stepping range. */
6823 /* If we are stepping at the source level and entered the runtime
6824 loader dynamic symbol resolution code...
6826 EXEC_FORWARD: we keep on single stepping until we exit the run
6827 time loader code and reach the callee's address.
6829 EXEC_REVERSE: we've already executed the callee (backward), and
6830 the runtime loader code is handled just like any other
6831 undebuggable function call. Now we need only keep stepping
6832 backward through the trampoline code, and that's handled further
6833 down, so there is nothing for us to do here. */
6835 if (execution_direction
!= EXEC_REVERSE
6836 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6837 && in_solib_dynsym_resolve_code (ecs
->event_thread
->suspend
.stop_pc
))
6839 CORE_ADDR pc_after_resolver
=
6840 gdbarch_skip_solib_resolver (gdbarch
,
6841 ecs
->event_thread
->suspend
.stop_pc
);
6843 infrun_debug_printf ("stepped into dynsym resolve code");
6845 if (pc_after_resolver
)
6847 /* Set up a step-resume breakpoint at the address
6848 indicated by SKIP_SOLIB_RESOLVER. */
6849 symtab_and_line sr_sal
;
6850 sr_sal
.pc
= pc_after_resolver
;
6851 sr_sal
.pspace
= get_frame_program_space (frame
);
6853 insert_step_resume_breakpoint_at_sal (gdbarch
,
6854 sr_sal
, null_frame_id
);
6861 /* Step through an indirect branch thunk. */
6862 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6863 && gdbarch_in_indirect_branch_thunk (gdbarch
,
6864 ecs
->event_thread
->suspend
.stop_pc
))
6866 infrun_debug_printf ("stepped into indirect branch thunk");
6871 if (ecs
->event_thread
->control
.step_range_end
!= 1
6872 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6873 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6874 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
6876 infrun_debug_printf ("stepped into signal trampoline");
6877 /* The inferior, while doing a "step" or "next", has ended up in
6878 a signal trampoline (either by a signal being delivered or by
6879 the signal handler returning). Just single-step until the
6880 inferior leaves the trampoline (either by calling the handler
6886 /* If we're in the return path from a shared library trampoline,
6887 we want to proceed through the trampoline when stepping. */
6888 /* macro/2012-04-25: This needs to come before the subroutine
6889 call check below as on some targets return trampolines look
6890 like subroutine calls (MIPS16 return thunks). */
6891 if (gdbarch_in_solib_return_trampoline (gdbarch
,
6892 ecs
->event_thread
->suspend
.stop_pc
,
6893 ecs
->stop_func_name
)
6894 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6896 /* Determine where this trampoline returns. */
6897 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6898 CORE_ADDR real_stop_pc
6899 = gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6901 infrun_debug_printf ("stepped into solib return tramp");
6903 /* Only proceed through if we know where it's going. */
6906 /* And put the step-breakpoint there and go until there. */
6907 symtab_and_line sr_sal
;
6908 sr_sal
.pc
= real_stop_pc
;
6909 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6910 sr_sal
.pspace
= get_frame_program_space (frame
);
6912 /* Do not specify what the fp should be when we stop since
6913 on some machines the prologue is where the new fp value
6915 insert_step_resume_breakpoint_at_sal (gdbarch
,
6916 sr_sal
, null_frame_id
);
6918 /* Restart without fiddling with the step ranges or
6925 /* Check for subroutine calls. The check for the current frame
6926 equalling the step ID is not necessary - the check of the
6927 previous frame's ID is sufficient - but it is a common case and
6928 cheaper than checking the previous frame's ID.
6930 NOTE: frame_id_eq will never report two invalid frame IDs as
6931 being equal, so to get into this block, both the current and
6932 previous frame must have valid frame IDs. */
6933 /* The outer_frame_id check is a heuristic to detect stepping
6934 through startup code. If we step over an instruction which
6935 sets the stack pointer from an invalid value to a valid value,
6936 we may detect that as a subroutine call from the mythical
6937 "outermost" function. This could be fixed by marking
6938 outermost frames as !stack_p,code_p,special_p. Then the
6939 initial outermost frame, before sp was valid, would
6940 have code_addr == &_start. See the comment in frame_id_eq
6942 if (!frame_id_eq (get_stack_frame_id (frame
),
6943 ecs
->event_thread
->control
.step_stack_frame_id
)
6944 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6945 ecs
->event_thread
->control
.step_stack_frame_id
)
6946 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
6948 || (ecs
->event_thread
->control
.step_start_function
6949 != find_pc_function (ecs
->event_thread
->suspend
.stop_pc
)))))
6951 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6952 CORE_ADDR real_stop_pc
;
6954 infrun_debug_printf ("stepped into subroutine");
6956 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
6958 /* I presume that step_over_calls is only 0 when we're
6959 supposed to be stepping at the assembly language level
6960 ("stepi"). Just stop. */
6961 /* And this works the same backward as frontward. MVS */
6962 end_stepping_range (ecs
);
6966 /* Reverse stepping through solib trampolines. */
6968 if (execution_direction
== EXEC_REVERSE
6969 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6970 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6971 || (ecs
->stop_func_start
== 0
6972 && in_solib_dynsym_resolve_code (stop_pc
))))
6974 /* Any solib trampoline code can be handled in reverse
6975 by simply continuing to single-step. We have already
6976 executed the solib function (backwards), and a few
6977 steps will take us back through the trampoline to the
6983 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6985 /* We're doing a "next".
6987 Normal (forward) execution: set a breakpoint at the
6988 callee's return address (the address at which the caller
6991 Reverse (backward) execution. set the step-resume
6992 breakpoint at the start of the function that we just
6993 stepped into (backwards), and continue to there. When we
6994 get there, we'll need to single-step back to the caller. */
6996 if (execution_direction
== EXEC_REVERSE
)
6998 /* If we're already at the start of the function, we've either
6999 just stepped backward into a single instruction function,
7000 or stepped back out of a signal handler to the first instruction
7001 of the function. Just keep going, which will single-step back
7003 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
7005 /* Normal function call return (static or dynamic). */
7006 symtab_and_line sr_sal
;
7007 sr_sal
.pc
= ecs
->stop_func_start
;
7008 sr_sal
.pspace
= get_frame_program_space (frame
);
7009 insert_step_resume_breakpoint_at_sal (gdbarch
,
7010 sr_sal
, null_frame_id
);
7014 insert_step_resume_breakpoint_at_caller (frame
);
7020 /* If we are in a function call trampoline (a stub between the
7021 calling routine and the real function), locate the real
7022 function. That's what tells us (a) whether we want to step
7023 into it at all, and (b) what prologue we want to run to the
7024 end of, if we do step into it. */
7025 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
7026 if (real_stop_pc
== 0)
7027 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
7028 if (real_stop_pc
!= 0)
7029 ecs
->stop_func_start
= real_stop_pc
;
7031 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
7033 symtab_and_line sr_sal
;
7034 sr_sal
.pc
= ecs
->stop_func_start
;
7035 sr_sal
.pspace
= get_frame_program_space (frame
);
7037 insert_step_resume_breakpoint_at_sal (gdbarch
,
7038 sr_sal
, null_frame_id
);
7043 /* If we have line number information for the function we are
7044 thinking of stepping into and the function isn't on the skip
7047 If there are several symtabs at that PC (e.g. with include
7048 files), just want to know whether *any* of them have line
7049 numbers. find_pc_line handles this. */
7051 struct symtab_and_line tmp_sal
;
7053 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7054 if (tmp_sal
.line
!= 0
7055 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
7057 && !inline_frame_is_marked_for_skip (true, ecs
->event_thread
))
7059 if (execution_direction
== EXEC_REVERSE
)
7060 handle_step_into_function_backward (gdbarch
, ecs
);
7062 handle_step_into_function (gdbarch
, ecs
);
7067 /* If we have no line number and the step-stop-if-no-debug is
7068 set, we stop the step so that the user has a chance to switch
7069 in assembly mode. */
7070 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
7071 && step_stop_if_no_debug
)
7073 end_stepping_range (ecs
);
7077 if (execution_direction
== EXEC_REVERSE
)
7079 /* If we're already at the start of the function, we've either just
7080 stepped backward into a single instruction function without line
7081 number info, or stepped back out of a signal handler to the first
7082 instruction of the function without line number info. Just keep
7083 going, which will single-step back to the caller. */
7084 if (ecs
->stop_func_start
!= stop_pc
)
7086 /* Set a breakpoint at callee's start address.
7087 From there we can step once and be back in the caller. */
7088 symtab_and_line sr_sal
;
7089 sr_sal
.pc
= ecs
->stop_func_start
;
7090 sr_sal
.pspace
= get_frame_program_space (frame
);
7091 insert_step_resume_breakpoint_at_sal (gdbarch
,
7092 sr_sal
, null_frame_id
);
7096 /* Set a breakpoint at callee's return address (the address
7097 at which the caller will resume). */
7098 insert_step_resume_breakpoint_at_caller (frame
);
7104 /* Reverse stepping through solib trampolines. */
7106 if (execution_direction
== EXEC_REVERSE
7107 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
7109 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
7111 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
7112 || (ecs
->stop_func_start
== 0
7113 && in_solib_dynsym_resolve_code (stop_pc
)))
7115 /* Any solib trampoline code can be handled in reverse
7116 by simply continuing to single-step. We have already
7117 executed the solib function (backwards), and a few
7118 steps will take us back through the trampoline to the
7123 else if (in_solib_dynsym_resolve_code (stop_pc
))
7125 /* Stepped backward into the solib dynsym resolver.
7126 Set a breakpoint at its start and continue, then
7127 one more step will take us out. */
7128 symtab_and_line sr_sal
;
7129 sr_sal
.pc
= ecs
->stop_func_start
;
7130 sr_sal
.pspace
= get_frame_program_space (frame
);
7131 insert_step_resume_breakpoint_at_sal (gdbarch
,
7132 sr_sal
, null_frame_id
);
7138 /* This always returns the sal for the inner-most frame when we are in a
7139 stack of inlined frames, even if GDB actually believes that it is in a
7140 more outer frame. This is checked for below by calls to
7141 inline_skipped_frames. */
7142 stop_pc_sal
= find_pc_line (ecs
->event_thread
->suspend
.stop_pc
, 0);
7144 /* NOTE: tausq/2004-05-24: This if block used to be done before all
7145 the trampoline processing logic, however, there are some trampolines
7146 that have no names, so we should do trampoline handling first. */
7147 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
7148 && ecs
->stop_func_name
== NULL
7149 && stop_pc_sal
.line
== 0)
7151 infrun_debug_printf ("stepped into undebuggable function");
7153 /* The inferior just stepped into, or returned to, an
7154 undebuggable function (where there is no debugging information
7155 and no line number corresponding to the address where the
7156 inferior stopped). Since we want to skip this kind of code,
7157 we keep going until the inferior returns from this
7158 function - unless the user has asked us not to (via
7159 set step-mode) or we no longer know how to get back
7160 to the call site. */
7161 if (step_stop_if_no_debug
7162 || !frame_id_p (frame_unwind_caller_id (frame
)))
7164 /* If we have no line number and the step-stop-if-no-debug
7165 is set, we stop the step so that the user has a chance to
7166 switch in assembly mode. */
7167 end_stepping_range (ecs
);
7172 /* Set a breakpoint at callee's return address (the address
7173 at which the caller will resume). */
7174 insert_step_resume_breakpoint_at_caller (frame
);
7180 if (ecs
->event_thread
->control
.step_range_end
== 1)
7182 /* It is stepi or nexti. We always want to stop stepping after
7184 infrun_debug_printf ("stepi/nexti");
7185 end_stepping_range (ecs
);
7189 if (stop_pc_sal
.line
== 0)
7191 /* We have no line number information. That means to stop
7192 stepping (does this always happen right after one instruction,
7193 when we do "s" in a function with no line numbers,
7194 or can this happen as a result of a return or longjmp?). */
7195 infrun_debug_printf ("line number info");
7196 end_stepping_range (ecs
);
7200 /* Look for "calls" to inlined functions, part one. If the inline
7201 frame machinery detected some skipped call sites, we have entered
7202 a new inline function. */
7204 if (frame_id_eq (get_frame_id (get_current_frame ()),
7205 ecs
->event_thread
->control
.step_frame_id
)
7206 && inline_skipped_frames (ecs
->event_thread
))
7208 infrun_debug_printf ("stepped into inlined function");
7210 symtab_and_line call_sal
= find_frame_sal (get_current_frame ());
7212 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
7214 /* For "step", we're going to stop. But if the call site
7215 for this inlined function is on the same source line as
7216 we were previously stepping, go down into the function
7217 first. Otherwise stop at the call site. */
7219 if (call_sal
.line
== ecs
->event_thread
->current_line
7220 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
7222 step_into_inline_frame (ecs
->event_thread
);
7223 if (inline_frame_is_marked_for_skip (false, ecs
->event_thread
))
7230 end_stepping_range (ecs
);
7235 /* For "next", we should stop at the call site if it is on a
7236 different source line. Otherwise continue through the
7237 inlined function. */
7238 if (call_sal
.line
== ecs
->event_thread
->current_line
7239 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
7242 end_stepping_range (ecs
);
7247 /* Look for "calls" to inlined functions, part two. If we are still
7248 in the same real function we were stepping through, but we have
7249 to go further up to find the exact frame ID, we are stepping
7250 through a more inlined call beyond its call site. */
7252 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
7253 && !frame_id_eq (get_frame_id (get_current_frame ()),
7254 ecs
->event_thread
->control
.step_frame_id
)
7255 && stepped_in_from (get_current_frame (),
7256 ecs
->event_thread
->control
.step_frame_id
))
7258 infrun_debug_printf ("stepping through inlined function");
7260 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
7261 || inline_frame_is_marked_for_skip (false, ecs
->event_thread
))
7264 end_stepping_range (ecs
);
7268 bool refresh_step_info
= true;
7269 if ((ecs
->event_thread
->suspend
.stop_pc
== stop_pc_sal
.pc
)
7270 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
7271 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
7273 /* We are at a different line. */
7275 if (stop_pc_sal
.is_stmt
)
7277 /* We are at the start of a statement.
7279 So stop. Note that we don't stop if we step into the middle of a
7280 statement. That is said to make things like for (;;) statements
7282 infrun_debug_printf ("stepped to a different line");
7283 end_stepping_range (ecs
);
7286 else if (frame_id_eq (get_frame_id (get_current_frame ()),
7287 ecs
->event_thread
->control
.step_frame_id
))
7289 /* We are not at the start of a statement, and we have not changed
7292 We ignore this line table entry, and continue stepping forward,
7293 looking for a better place to stop. */
7294 refresh_step_info
= false;
7295 infrun_debug_printf ("stepped to a different line, but "
7296 "it's not the start of a statement");
7300 /* We are not the start of a statement, and we have changed frame.
7302 We ignore this line table entry, and continue stepping forward,
7303 looking for a better place to stop. Keep refresh_step_info at
7304 true to note that the frame has changed, but ignore the line
7305 number to make sure we don't ignore a subsequent entry with the
7306 same line number. */
7307 stop_pc_sal
.line
= 0;
7308 infrun_debug_printf ("stepped to a different frame, but "
7309 "it's not the start of a statement");
7313 /* We aren't done stepping.
7315 Optimize by setting the stepping range to the line.
7316 (We might not be in the original line, but if we entered a
7317 new line in mid-statement, we continue stepping. This makes
7318 things like for(;;) statements work better.)
7320 If we entered a SAL that indicates a non-statement line table entry,
7321 then we update the stepping range, but we don't update the step info,
7322 which includes things like the line number we are stepping away from.
7323 This means we will stop when we find a line table entry that is marked
7324 as is-statement, even if it matches the non-statement one we just
7327 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
7328 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
7329 ecs
->event_thread
->control
.may_range_step
= 1;
7330 if (refresh_step_info
)
7331 set_step_info (ecs
->event_thread
, frame
, stop_pc_sal
);
7333 infrun_debug_printf ("keep going");
7337 static bool restart_stepped_thread (process_stratum_target
*resume_target
,
7338 ptid_t resume_ptid
);
7340 /* In all-stop mode, if we're currently stepping but have stopped in
7341 some other thread, we may need to switch back to the stepped
7342 thread. Returns true we set the inferior running, false if we left
7343 it stopped (and the event needs further processing). */
7346 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
7348 if (!target_is_non_stop_p ())
7350 /* If any thread is blocked on some internal breakpoint, and we
7351 simply need to step over that breakpoint to get it going
7352 again, do that first. */
7354 /* However, if we see an event for the stepping thread, then we
7355 know all other threads have been moved past their breakpoints
7356 already. Let the caller check whether the step is finished,
7357 etc., before deciding to move it past a breakpoint. */
7358 if (ecs
->event_thread
->control
.step_range_end
!= 0)
7361 /* Check if the current thread is blocked on an incomplete
7362 step-over, interrupted by a random signal. */
7363 if (ecs
->event_thread
->control
.trap_expected
7364 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
7367 ("need to finish step-over of [%s]",
7368 target_pid_to_str (ecs
->event_thread
->ptid
).c_str ());
7373 /* Check if the current thread is blocked by a single-step
7374 breakpoint of another thread. */
7375 if (ecs
->hit_singlestep_breakpoint
)
7377 infrun_debug_printf ("need to step [%s] over single-step breakpoint",
7378 target_pid_to_str (ecs
->ptid
).c_str ());
7383 /* If this thread needs yet another step-over (e.g., stepping
7384 through a delay slot), do it first before moving on to
7386 if (thread_still_needs_step_over (ecs
->event_thread
))
7389 ("thread [%s] still needs step-over",
7390 target_pid_to_str (ecs
->event_thread
->ptid
).c_str ());
7395 /* If scheduler locking applies even if not stepping, there's no
7396 need to walk over threads. Above we've checked whether the
7397 current thread is stepping. If some other thread not the
7398 event thread is stepping, then it must be that scheduler
7399 locking is not in effect. */
7400 if (schedlock_applies (ecs
->event_thread
))
7403 /* Otherwise, we no longer expect a trap in the current thread.
7404 Clear the trap_expected flag before switching back -- this is
7405 what keep_going does as well, if we call it. */
7406 ecs
->event_thread
->control
.trap_expected
= 0;
7408 /* Likewise, clear the signal if it should not be passed. */
7409 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7410 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7412 if (restart_stepped_thread (ecs
->target
, ecs
->ptid
))
7414 prepare_to_wait (ecs
);
7418 switch_to_thread (ecs
->event_thread
);
7424 /* Look for the thread that was stepping, and resume it.
7425 RESUME_TARGET / RESUME_PTID indicate the set of threads the caller
7426 is resuming. Return true if a thread was started, false
7430 restart_stepped_thread (process_stratum_target
*resume_target
,
7433 /* Do all pending step-overs before actually proceeding with
7435 if (start_step_over ())
7438 for (thread_info
*tp
: all_threads_safe ())
7440 if (tp
->state
== THREAD_EXITED
)
7443 if (tp
->suspend
.waitstatus_pending_p
)
7446 /* Ignore threads of processes the caller is not
7449 && (tp
->inf
->process_target () != resume_target
7450 || tp
->inf
->pid
!= resume_ptid
.pid ()))
7453 if (tp
->control
.trap_expected
)
7455 infrun_debug_printf ("switching back to stepped thread (step-over)");
7457 if (keep_going_stepped_thread (tp
))
7462 for (thread_info
*tp
: all_threads_safe ())
7464 if (tp
->state
== THREAD_EXITED
)
7467 if (tp
->suspend
.waitstatus_pending_p
)
7470 /* Ignore threads of processes the caller is not
7473 && (tp
->inf
->process_target () != resume_target
7474 || tp
->inf
->pid
!= resume_ptid
.pid ()))
7477 /* Did we find the stepping thread? */
7478 if (tp
->control
.step_range_end
)
7480 infrun_debug_printf ("switching back to stepped thread (stepping)");
7482 if (keep_going_stepped_thread (tp
))
7493 restart_after_all_stop_detach (process_stratum_target
*proc_target
)
7495 /* Note we don't check target_is_non_stop_p() here, because the
7496 current inferior may no longer have a process_stratum target
7497 pushed, as we just detached. */
7499 /* See if we have a THREAD_RUNNING thread that need to be
7500 re-resumed. If we have any thread that is already executing,
7501 then we don't need to resume the target -- it is already been
7502 resumed. With the remote target (in all-stop), it's even
7503 impossible to issue another resumption if the target is already
7504 resumed, until the target reports a stop. */
7505 for (thread_info
*thr
: all_threads (proc_target
))
7507 if (thr
->state
!= THREAD_RUNNING
)
7510 /* If we have any thread that is already executing, then we
7511 don't need to resume the target -- it is already been
7516 /* If we have a pending event to process, skip resuming the
7517 target and go straight to processing it. */
7518 if (thr
->resumed
&& thr
->suspend
.waitstatus_pending_p
)
7522 /* Alright, we need to re-resume the target. If a thread was
7523 stepping, we need to restart it stepping. */
7524 if (restart_stepped_thread (proc_target
, minus_one_ptid
))
7527 /* Otherwise, find the first THREAD_RUNNING thread and resume
7529 for (thread_info
*thr
: all_threads (proc_target
))
7531 if (thr
->state
!= THREAD_RUNNING
)
7534 execution_control_state ecs
;
7535 reset_ecs (&ecs
, thr
);
7536 switch_to_thread (thr
);
7542 /* Set a previously stepped thread back to stepping. Returns true on
7543 success, false if the resume is not possible (e.g., the thread
7547 keep_going_stepped_thread (struct thread_info
*tp
)
7549 struct frame_info
*frame
;
7550 struct execution_control_state ecss
;
7551 struct execution_control_state
*ecs
= &ecss
;
7553 /* If the stepping thread exited, then don't try to switch back and
7554 resume it, which could fail in several different ways depending
7555 on the target. Instead, just keep going.
7557 We can find a stepping dead thread in the thread list in two
7560 - The target supports thread exit events, and when the target
7561 tries to delete the thread from the thread list, inferior_ptid
7562 pointed at the exiting thread. In such case, calling
7563 delete_thread does not really remove the thread from the list;
7564 instead, the thread is left listed, with 'exited' state.
7566 - The target's debug interface does not support thread exit
7567 events, and so we have no idea whatsoever if the previously
7568 stepping thread is still alive. For that reason, we need to
7569 synchronously query the target now. */
7571 if (tp
->state
== THREAD_EXITED
|| !target_thread_alive (tp
->ptid
))
7573 infrun_debug_printf ("not resuming previously stepped thread, it has "
7580 infrun_debug_printf ("resuming previously stepped thread");
7582 reset_ecs (ecs
, tp
);
7583 switch_to_thread (tp
);
7585 tp
->suspend
.stop_pc
= regcache_read_pc (get_thread_regcache (tp
));
7586 frame
= get_current_frame ();
7588 /* If the PC of the thread we were trying to single-step has
7589 changed, then that thread has trapped or been signaled, but the
7590 event has not been reported to GDB yet. Re-poll the target
7591 looking for this particular thread's event (i.e. temporarily
7592 enable schedlock) by:
7594 - setting a break at the current PC
7595 - resuming that particular thread, only (by setting trap
7598 This prevents us continuously moving the single-step breakpoint
7599 forward, one instruction at a time, overstepping. */
7601 if (tp
->suspend
.stop_pc
!= tp
->prev_pc
)
7605 infrun_debug_printf ("expected thread advanced also (%s -> %s)",
7606 paddress (target_gdbarch (), tp
->prev_pc
),
7607 paddress (target_gdbarch (), tp
->suspend
.stop_pc
));
7609 /* Clear the info of the previous step-over, as it's no longer
7610 valid (if the thread was trying to step over a breakpoint, it
7611 has already succeeded). It's what keep_going would do too,
7612 if we called it. Do this before trying to insert the sss
7613 breakpoint, otherwise if we were previously trying to step
7614 over this exact address in another thread, the breakpoint is
7616 clear_step_over_info ();
7617 tp
->control
.trap_expected
= 0;
7619 insert_single_step_breakpoint (get_frame_arch (frame
),
7620 get_frame_address_space (frame
),
7621 tp
->suspend
.stop_pc
);
7624 resume_ptid
= internal_resume_ptid (tp
->control
.stepping_command
);
7625 do_target_resume (resume_ptid
, false, GDB_SIGNAL_0
);
7629 infrun_debug_printf ("expected thread still hasn't advanced");
7631 keep_going_pass_signal (ecs
);
7637 /* Is thread TP in the middle of (software or hardware)
7638 single-stepping? (Note the result of this function must never be
7639 passed directly as target_resume's STEP parameter.) */
7642 currently_stepping (struct thread_info
*tp
)
7644 return ((tp
->control
.step_range_end
7645 && tp
->control
.step_resume_breakpoint
== NULL
)
7646 || tp
->control
.trap_expected
7647 || tp
->stepped_breakpoint
7648 || bpstat_should_step ());
7651 /* Inferior has stepped into a subroutine call with source code that
7652 we should not step over. Do step to the first line of code in
7656 handle_step_into_function (struct gdbarch
*gdbarch
,
7657 struct execution_control_state
*ecs
)
7659 fill_in_stop_func (gdbarch
, ecs
);
7661 compunit_symtab
*cust
7662 = find_pc_compunit_symtab (ecs
->event_thread
->suspend
.stop_pc
);
7663 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7664 ecs
->stop_func_start
7665 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7667 symtab_and_line stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7668 /* Use the step_resume_break to step until the end of the prologue,
7669 even if that involves jumps (as it seems to on the vax under
7671 /* If the prologue ends in the middle of a source line, continue to
7672 the end of that source line (if it is still within the function).
7673 Otherwise, just go to end of prologue. */
7674 if (stop_func_sal
.end
7675 && stop_func_sal
.pc
!= ecs
->stop_func_start
7676 && stop_func_sal
.end
< ecs
->stop_func_end
)
7677 ecs
->stop_func_start
= stop_func_sal
.end
;
7679 /* Architectures which require breakpoint adjustment might not be able
7680 to place a breakpoint at the computed address. If so, the test
7681 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7682 ecs->stop_func_start to an address at which a breakpoint may be
7683 legitimately placed.
7685 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7686 made, GDB will enter an infinite loop when stepping through
7687 optimized code consisting of VLIW instructions which contain
7688 subinstructions corresponding to different source lines. On
7689 FR-V, it's not permitted to place a breakpoint on any but the
7690 first subinstruction of a VLIW instruction. When a breakpoint is
7691 set, GDB will adjust the breakpoint address to the beginning of
7692 the VLIW instruction. Thus, we need to make the corresponding
7693 adjustment here when computing the stop address. */
7695 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
7697 ecs
->stop_func_start
7698 = gdbarch_adjust_breakpoint_address (gdbarch
,
7699 ecs
->stop_func_start
);
7702 if (ecs
->stop_func_start
== ecs
->event_thread
->suspend
.stop_pc
)
7704 /* We are already there: stop now. */
7705 end_stepping_range (ecs
);
7710 /* Put the step-breakpoint there and go until there. */
7711 symtab_and_line sr_sal
;
7712 sr_sal
.pc
= ecs
->stop_func_start
;
7713 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
7714 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
7716 /* Do not specify what the fp should be when we stop since on
7717 some machines the prologue is where the new fp value is
7719 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
7721 /* And make sure stepping stops right away then. */
7722 ecs
->event_thread
->control
.step_range_end
7723 = ecs
->event_thread
->control
.step_range_start
;
7728 /* Inferior has stepped backward into a subroutine call with source
7729 code that we should not step over. Do step to the beginning of the
7730 last line of code in it. */
7733 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
7734 struct execution_control_state
*ecs
)
7736 struct compunit_symtab
*cust
;
7737 struct symtab_and_line stop_func_sal
;
7739 fill_in_stop_func (gdbarch
, ecs
);
7741 cust
= find_pc_compunit_symtab (ecs
->event_thread
->suspend
.stop_pc
);
7742 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7743 ecs
->stop_func_start
7744 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7746 stop_func_sal
= find_pc_line (ecs
->event_thread
->suspend
.stop_pc
, 0);
7748 /* OK, we're just going to keep stepping here. */
7749 if (stop_func_sal
.pc
== ecs
->event_thread
->suspend
.stop_pc
)
7751 /* We're there already. Just stop stepping now. */
7752 end_stepping_range (ecs
);
7756 /* Else just reset the step range and keep going.
7757 No step-resume breakpoint, they don't work for
7758 epilogues, which can have multiple entry paths. */
7759 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
7760 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
7766 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7767 This is used to both functions and to skip over code. */
7770 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
7771 struct symtab_and_line sr_sal
,
7772 struct frame_id sr_id
,
7773 enum bptype sr_type
)
7775 /* There should never be more than one step-resume or longjmp-resume
7776 breakpoint per thread, so we should never be setting a new
7777 step_resume_breakpoint when one is already active. */
7778 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
7779 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
7781 infrun_debug_printf ("inserting step-resume breakpoint at %s",
7782 paddress (gdbarch
, sr_sal
.pc
));
7784 inferior_thread ()->control
.step_resume_breakpoint
7785 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
).release ();
7789 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
7790 struct symtab_and_line sr_sal
,
7791 struct frame_id sr_id
)
7793 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
7798 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7799 This is used to skip a potential signal handler.
7801 This is called with the interrupted function's frame. The signal
7802 handler, when it returns, will resume the interrupted function at
7806 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
7808 gdb_assert (return_frame
!= NULL
);
7810 struct gdbarch
*gdbarch
= get_frame_arch (return_frame
);
7812 symtab_and_line sr_sal
;
7813 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
7814 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7815 sr_sal
.pspace
= get_frame_program_space (return_frame
);
7817 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
7818 get_stack_frame_id (return_frame
),
7822 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7823 is used to skip a function after stepping into it (for "next" or if
7824 the called function has no debugging information).
7826 The current function has almost always been reached by single
7827 stepping a call or return instruction. NEXT_FRAME belongs to the
7828 current function, and the breakpoint will be set at the caller's
7831 This is a separate function rather than reusing
7832 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7833 get_prev_frame, which may stop prematurely (see the implementation
7834 of frame_unwind_caller_id for an example). */
7837 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
7839 /* We shouldn't have gotten here if we don't know where the call site
7841 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
7843 struct gdbarch
*gdbarch
= frame_unwind_caller_arch (next_frame
);
7845 symtab_and_line sr_sal
;
7846 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
7847 frame_unwind_caller_pc (next_frame
));
7848 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7849 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
7851 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
7852 frame_unwind_caller_id (next_frame
));
7855 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7856 new breakpoint at the target of a jmp_buf. The handling of
7857 longjmp-resume uses the same mechanisms used for handling
7858 "step-resume" breakpoints. */
7861 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
7863 /* There should never be more than one longjmp-resume breakpoint per
7864 thread, so we should never be setting a new
7865 longjmp_resume_breakpoint when one is already active. */
7866 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
7868 infrun_debug_printf ("inserting longjmp-resume breakpoint at %s",
7869 paddress (gdbarch
, pc
));
7871 inferior_thread ()->control
.exception_resume_breakpoint
=
7872 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
).release ();
7875 /* Insert an exception resume breakpoint. TP is the thread throwing
7876 the exception. The block B is the block of the unwinder debug hook
7877 function. FRAME is the frame corresponding to the call to this
7878 function. SYM is the symbol of the function argument holding the
7879 target PC of the exception. */
7882 insert_exception_resume_breakpoint (struct thread_info
*tp
,
7883 const struct block
*b
,
7884 struct frame_info
*frame
,
7889 struct block_symbol vsym
;
7890 struct value
*value
;
7892 struct breakpoint
*bp
;
7894 vsym
= lookup_symbol_search_name (sym
->search_name (),
7896 value
= read_var_value (vsym
.symbol
, vsym
.block
, frame
);
7897 /* If the value was optimized out, revert to the old behavior. */
7898 if (! value_optimized_out (value
))
7900 handler
= value_as_address (value
);
7902 infrun_debug_printf ("exception resume at %lx",
7903 (unsigned long) handler
);
7905 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7907 bp_exception_resume
).release ();
7909 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7912 bp
->thread
= tp
->global_num
;
7913 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7916 catch (const gdb_exception_error
&e
)
7918 /* We want to ignore errors here. */
7922 /* A helper for check_exception_resume that sets an
7923 exception-breakpoint based on a SystemTap probe. */
7926 insert_exception_resume_from_probe (struct thread_info
*tp
,
7927 const struct bound_probe
*probe
,
7928 struct frame_info
*frame
)
7930 struct value
*arg_value
;
7932 struct breakpoint
*bp
;
7934 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
7938 handler
= value_as_address (arg_value
);
7940 infrun_debug_printf ("exception resume at %s",
7941 paddress (probe
->objfile
->arch (), handler
));
7943 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7944 handler
, bp_exception_resume
).release ();
7945 bp
->thread
= tp
->global_num
;
7946 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7949 /* This is called when an exception has been intercepted. Check to
7950 see whether the exception's destination is of interest, and if so,
7951 set an exception resume breakpoint there. */
7954 check_exception_resume (struct execution_control_state
*ecs
,
7955 struct frame_info
*frame
)
7957 struct bound_probe probe
;
7958 struct symbol
*func
;
7960 /* First see if this exception unwinding breakpoint was set via a
7961 SystemTap probe point. If so, the probe has two arguments: the
7962 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7963 set a breakpoint there. */
7964 probe
= find_probe_by_pc (get_frame_pc (frame
));
7967 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
7971 func
= get_frame_function (frame
);
7977 const struct block
*b
;
7978 struct block_iterator iter
;
7982 /* The exception breakpoint is a thread-specific breakpoint on
7983 the unwinder's debug hook, declared as:
7985 void _Unwind_DebugHook (void *cfa, void *handler);
7987 The CFA argument indicates the frame to which control is
7988 about to be transferred. HANDLER is the destination PC.
7990 We ignore the CFA and set a temporary breakpoint at HANDLER.
7991 This is not extremely efficient but it avoids issues in gdb
7992 with computing the DWARF CFA, and it also works even in weird
7993 cases such as throwing an exception from inside a signal
7996 b
= SYMBOL_BLOCK_VALUE (func
);
7997 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
7999 if (!SYMBOL_IS_ARGUMENT (sym
))
8006 insert_exception_resume_breakpoint (ecs
->event_thread
,
8012 catch (const gdb_exception_error
&e
)
8018 stop_waiting (struct execution_control_state
*ecs
)
8020 infrun_debug_printf ("stop_waiting");
8022 /* Let callers know we don't want to wait for the inferior anymore. */
8023 ecs
->wait_some_more
= 0;
8025 /* If all-stop, but there exists a non-stop target, stop all
8026 threads now that we're presenting the stop to the user. */
8027 if (!non_stop
&& exists_non_stop_target ())
8028 stop_all_threads ();
8031 /* Like keep_going, but passes the signal to the inferior, even if the
8032 signal is set to nopass. */
8035 keep_going_pass_signal (struct execution_control_state
*ecs
)
8037 gdb_assert (ecs
->event_thread
->ptid
== inferior_ptid
);
8038 gdb_assert (!ecs
->event_thread
->resumed
);
8040 /* Save the pc before execution, to compare with pc after stop. */
8041 ecs
->event_thread
->prev_pc
8042 = regcache_read_pc_protected (get_thread_regcache (ecs
->event_thread
));
8044 if (ecs
->event_thread
->control
.trap_expected
)
8046 struct thread_info
*tp
= ecs
->event_thread
;
8048 infrun_debug_printf ("%s has trap_expected set, "
8049 "resuming to collect trap",
8050 target_pid_to_str (tp
->ptid
).c_str ());
8052 /* We haven't yet gotten our trap, and either: intercepted a
8053 non-signal event (e.g., a fork); or took a signal which we
8054 are supposed to pass through to the inferior. Simply
8056 resume (ecs
->event_thread
->suspend
.stop_signal
);
8058 else if (step_over_info_valid_p ())
8060 /* Another thread is stepping over a breakpoint in-line. If
8061 this thread needs a step-over too, queue the request. In
8062 either case, this resume must be deferred for later. */
8063 struct thread_info
*tp
= ecs
->event_thread
;
8065 if (ecs
->hit_singlestep_breakpoint
8066 || thread_still_needs_step_over (tp
))
8068 infrun_debug_printf ("step-over already in progress: "
8069 "step-over for %s deferred",
8070 target_pid_to_str (tp
->ptid
).c_str ());
8071 global_thread_step_over_chain_enqueue (tp
);
8075 infrun_debug_printf ("step-over in progress: resume of %s deferred",
8076 target_pid_to_str (tp
->ptid
).c_str ());
8081 struct regcache
*regcache
= get_current_regcache ();
8084 step_over_what step_what
;
8086 /* Either the trap was not expected, but we are continuing
8087 anyway (if we got a signal, the user asked it be passed to
8090 We got our expected trap, but decided we should resume from
8093 We're going to run this baby now!
8095 Note that insert_breakpoints won't try to re-insert
8096 already inserted breakpoints. Therefore, we don't
8097 care if breakpoints were already inserted, or not. */
8099 /* If we need to step over a breakpoint, and we're not using
8100 displaced stepping to do so, insert all breakpoints
8101 (watchpoints, etc.) but the one we're stepping over, step one
8102 instruction, and then re-insert the breakpoint when that step
8105 step_what
= thread_still_needs_step_over (ecs
->event_thread
);
8107 remove_bp
= (ecs
->hit_singlestep_breakpoint
8108 || (step_what
& STEP_OVER_BREAKPOINT
));
8109 remove_wps
= (step_what
& STEP_OVER_WATCHPOINT
);
8111 /* We can't use displaced stepping if we need to step past a
8112 watchpoint. The instruction copied to the scratch pad would
8113 still trigger the watchpoint. */
8115 && (remove_wps
|| !use_displaced_stepping (ecs
->event_thread
)))
8117 set_step_over_info (regcache
->aspace (),
8118 regcache_read_pc (regcache
), remove_wps
,
8119 ecs
->event_thread
->global_num
);
8121 else if (remove_wps
)
8122 set_step_over_info (NULL
, 0, remove_wps
, -1);
8124 /* If we now need to do an in-line step-over, we need to stop
8125 all other threads. Note this must be done before
8126 insert_breakpoints below, because that removes the breakpoint
8127 we're about to step over, otherwise other threads could miss
8129 if (step_over_info_valid_p () && target_is_non_stop_p ())
8130 stop_all_threads ();
8132 /* Stop stepping if inserting breakpoints fails. */
8135 insert_breakpoints ();
8137 catch (const gdb_exception_error
&e
)
8139 exception_print (gdb_stderr
, e
);
8141 clear_step_over_info ();
8145 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
8147 resume (ecs
->event_thread
->suspend
.stop_signal
);
8150 prepare_to_wait (ecs
);
8153 /* Called when we should continue running the inferior, because the
8154 current event doesn't cause a user visible stop. This does the
8155 resuming part; waiting for the next event is done elsewhere. */
8158 keep_going (struct execution_control_state
*ecs
)
8160 if (ecs
->event_thread
->control
.trap_expected
8161 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
8162 ecs
->event_thread
->control
.trap_expected
= 0;
8164 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
8165 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
8166 keep_going_pass_signal (ecs
);
8169 /* This function normally comes after a resume, before
8170 handle_inferior_event exits. It takes care of any last bits of
8171 housekeeping, and sets the all-important wait_some_more flag. */
8174 prepare_to_wait (struct execution_control_state
*ecs
)
8176 infrun_debug_printf ("prepare_to_wait");
8178 ecs
->wait_some_more
= 1;
8180 /* If the target can't async, emulate it by marking the infrun event
8181 handler such that as soon as we get back to the event-loop, we
8182 immediately end up in fetch_inferior_event again calling
8184 if (!target_can_async_p ())
8185 mark_infrun_async_event_handler ();
8188 /* We are done with the step range of a step/next/si/ni command.
8189 Called once for each n of a "step n" operation. */
8192 end_stepping_range (struct execution_control_state
*ecs
)
8194 ecs
->event_thread
->control
.stop_step
= 1;
8198 /* Several print_*_reason functions to print why the inferior has stopped.
8199 We always print something when the inferior exits, or receives a signal.
8200 The rest of the cases are dealt with later on in normal_stop and
8201 print_it_typical. Ideally there should be a call to one of these
8202 print_*_reason functions functions from handle_inferior_event each time
8203 stop_waiting is called.
8205 Note that we don't call these directly, instead we delegate that to
8206 the interpreters, through observers. Interpreters then call these
8207 with whatever uiout is right. */
8210 print_end_stepping_range_reason (struct ui_out
*uiout
)
8212 /* For CLI-like interpreters, print nothing. */
8214 if (uiout
->is_mi_like_p ())
8216 uiout
->field_string ("reason",
8217 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
8222 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
8224 annotate_signalled ();
8225 if (uiout
->is_mi_like_p ())
8227 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
8228 uiout
->text ("\nProgram terminated with signal ");
8229 annotate_signal_name ();
8230 uiout
->field_string ("signal-name",
8231 gdb_signal_to_name (siggnal
));
8232 annotate_signal_name_end ();
8234 annotate_signal_string ();
8235 uiout
->field_string ("signal-meaning",
8236 gdb_signal_to_string (siggnal
));
8237 annotate_signal_string_end ();
8238 uiout
->text (".\n");
8239 uiout
->text ("The program no longer exists.\n");
8243 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
8245 struct inferior
*inf
= current_inferior ();
8246 std::string pidstr
= target_pid_to_str (ptid_t (inf
->pid
));
8248 annotate_exited (exitstatus
);
8251 if (uiout
->is_mi_like_p ())
8252 uiout
->field_string ("reason", async_reason_lookup (EXEC_ASYNC_EXITED
));
8253 std::string exit_code_str
8254 = string_printf ("0%o", (unsigned int) exitstatus
);
8255 uiout
->message ("[Inferior %s (%s) exited with code %pF]\n",
8256 plongest (inf
->num
), pidstr
.c_str (),
8257 string_field ("exit-code", exit_code_str
.c_str ()));
8261 if (uiout
->is_mi_like_p ())
8263 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
8264 uiout
->message ("[Inferior %s (%s) exited normally]\n",
8265 plongest (inf
->num
), pidstr
.c_str ());
8270 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
8272 struct thread_info
*thr
= inferior_thread ();
8276 if (uiout
->is_mi_like_p ())
8278 else if (show_thread_that_caused_stop ())
8282 uiout
->text ("\nThread ");
8283 uiout
->field_string ("thread-id", print_thread_id (thr
));
8285 name
= thr
->name
!= NULL
? thr
->name
: target_thread_name (thr
);
8288 uiout
->text (" \"");
8289 uiout
->field_string ("name", name
);
8294 uiout
->text ("\nProgram");
8296 if (siggnal
== GDB_SIGNAL_0
&& !uiout
->is_mi_like_p ())
8297 uiout
->text (" stopped");
8300 uiout
->text (" received signal ");
8301 annotate_signal_name ();
8302 if (uiout
->is_mi_like_p ())
8304 ("reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
8305 uiout
->field_string ("signal-name", gdb_signal_to_name (siggnal
));
8306 annotate_signal_name_end ();
8308 annotate_signal_string ();
8309 uiout
->field_string ("signal-meaning", gdb_signal_to_string (siggnal
));
8311 struct regcache
*regcache
= get_current_regcache ();
8312 struct gdbarch
*gdbarch
= regcache
->arch ();
8313 if (gdbarch_report_signal_info_p (gdbarch
))
8314 gdbarch_report_signal_info (gdbarch
, uiout
, siggnal
);
8316 annotate_signal_string_end ();
8318 uiout
->text (".\n");
8322 print_no_history_reason (struct ui_out
*uiout
)
8324 uiout
->text ("\nNo more reverse-execution history.\n");
8327 /* Print current location without a level number, if we have changed
8328 functions or hit a breakpoint. Print source line if we have one.
8329 bpstat_print contains the logic deciding in detail what to print,
8330 based on the event(s) that just occurred. */
8333 print_stop_location (struct target_waitstatus
*ws
)
8336 enum print_what source_flag
;
8337 int do_frame_printing
= 1;
8338 struct thread_info
*tp
= inferior_thread ();
8340 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
8344 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
8345 should) carry around the function and does (or should) use
8346 that when doing a frame comparison. */
8347 if (tp
->control
.stop_step
8348 && frame_id_eq (tp
->control
.step_frame_id
,
8349 get_frame_id (get_current_frame ()))
8350 && (tp
->control
.step_start_function
8351 == find_pc_function (tp
->suspend
.stop_pc
)))
8353 /* Finished step, just print source line. */
8354 source_flag
= SRC_LINE
;
8358 /* Print location and source line. */
8359 source_flag
= SRC_AND_LOC
;
8362 case PRINT_SRC_AND_LOC
:
8363 /* Print location and source line. */
8364 source_flag
= SRC_AND_LOC
;
8366 case PRINT_SRC_ONLY
:
8367 source_flag
= SRC_LINE
;
8370 /* Something bogus. */
8371 source_flag
= SRC_LINE
;
8372 do_frame_printing
= 0;
8375 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
8378 /* The behavior of this routine with respect to the source
8380 SRC_LINE: Print only source line
8381 LOCATION: Print only location
8382 SRC_AND_LOC: Print location and source line. */
8383 if (do_frame_printing
)
8384 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
8390 print_stop_event (struct ui_out
*uiout
, bool displays
)
8392 struct target_waitstatus last
;
8393 struct thread_info
*tp
;
8395 get_last_target_status (nullptr, nullptr, &last
);
8398 scoped_restore save_uiout
= make_scoped_restore (¤t_uiout
, uiout
);
8400 print_stop_location (&last
);
8402 /* Display the auto-display expressions. */
8407 tp
= inferior_thread ();
8408 if (tp
->thread_fsm
!= NULL
8409 && tp
->thread_fsm
->finished_p ())
8411 struct return_value_info
*rv
;
8413 rv
= tp
->thread_fsm
->return_value ();
8415 print_return_value (uiout
, rv
);
8422 maybe_remove_breakpoints (void)
8424 if (!breakpoints_should_be_inserted_now () && target_has_execution ())
8426 if (remove_breakpoints ())
8428 target_terminal::ours_for_output ();
8429 printf_filtered (_("Cannot remove breakpoints because "
8430 "program is no longer writable.\nFurther "
8431 "execution is probably impossible.\n"));
8436 /* The execution context that just caused a normal stop. */
8442 DISABLE_COPY_AND_ASSIGN (stop_context
);
8444 bool changed () const;
8449 /* The event PTID. */
8453 /* If stopp for a thread event, this is the thread that caused the
8455 thread_info_ref thread
;
8457 /* The inferior that caused the stop. */
8461 /* Initializes a new stop context. If stopped for a thread event, this
8462 takes a strong reference to the thread. */
8464 stop_context::stop_context ()
8466 stop_id
= get_stop_id ();
8467 ptid
= inferior_ptid
;
8468 inf_num
= current_inferior ()->num
;
8470 if (inferior_ptid
!= null_ptid
)
8472 /* Take a strong reference so that the thread can't be deleted
8474 thread
= thread_info_ref::new_reference (inferior_thread ());
8478 /* Return true if the current context no longer matches the saved stop
8482 stop_context::changed () const
8484 if (ptid
!= inferior_ptid
)
8486 if (inf_num
!= current_inferior ()->num
)
8488 if (thread
!= NULL
&& thread
->state
!= THREAD_STOPPED
)
8490 if (get_stop_id () != stop_id
)
8500 struct target_waitstatus last
;
8502 get_last_target_status (nullptr, nullptr, &last
);
8506 /* If an exception is thrown from this point on, make sure to
8507 propagate GDB's knowledge of the executing state to the
8508 frontend/user running state. A QUIT is an easy exception to see
8509 here, so do this before any filtered output. */
8511 ptid_t finish_ptid
= null_ptid
;
8514 finish_ptid
= minus_one_ptid
;
8515 else if (last
.kind
== TARGET_WAITKIND_SIGNALLED
8516 || last
.kind
== TARGET_WAITKIND_EXITED
)
8518 /* On some targets, we may still have live threads in the
8519 inferior when we get a process exit event. E.g., for
8520 "checkpoint", when the current checkpoint/fork exits,
8521 linux-fork.c automatically switches to another fork from
8522 within target_mourn_inferior. */
8523 if (inferior_ptid
!= null_ptid
)
8524 finish_ptid
= ptid_t (inferior_ptid
.pid ());
8526 else if (last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8527 finish_ptid
= inferior_ptid
;
8529 gdb::optional
<scoped_finish_thread_state
> maybe_finish_thread_state
;
8530 if (finish_ptid
!= null_ptid
)
8532 maybe_finish_thread_state
.emplace
8533 (user_visible_resume_target (finish_ptid
), finish_ptid
);
8536 /* As we're presenting a stop, and potentially removing breakpoints,
8537 update the thread list so we can tell whether there are threads
8538 running on the target. With target remote, for example, we can
8539 only learn about new threads when we explicitly update the thread
8540 list. Do this before notifying the interpreters about signal
8541 stops, end of stepping ranges, etc., so that the "new thread"
8542 output is emitted before e.g., "Program received signal FOO",
8543 instead of after. */
8544 update_thread_list ();
8546 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
8547 gdb::observers::signal_received
.notify (inferior_thread ()->suspend
.stop_signal
);
8549 /* As with the notification of thread events, we want to delay
8550 notifying the user that we've switched thread context until
8551 the inferior actually stops.
8553 There's no point in saying anything if the inferior has exited.
8554 Note that SIGNALLED here means "exited with a signal", not
8555 "received a signal".
8557 Also skip saying anything in non-stop mode. In that mode, as we
8558 don't want GDB to switch threads behind the user's back, to avoid
8559 races where the user is typing a command to apply to thread x,
8560 but GDB switches to thread y before the user finishes entering
8561 the command, fetch_inferior_event installs a cleanup to restore
8562 the current thread back to the thread the user had selected right
8563 after this event is handled, so we're not really switching, only
8564 informing of a stop. */
8566 && previous_inferior_ptid
!= inferior_ptid
8567 && target_has_execution ()
8568 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
8569 && last
.kind
!= TARGET_WAITKIND_EXITED
8570 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8572 SWITCH_THRU_ALL_UIS ()
8574 target_terminal::ours_for_output ();
8575 printf_filtered (_("[Switching to %s]\n"),
8576 target_pid_to_str (inferior_ptid
).c_str ());
8577 annotate_thread_changed ();
8579 previous_inferior_ptid
= inferior_ptid
;
8582 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
8584 SWITCH_THRU_ALL_UIS ()
8585 if (current_ui
->prompt_state
== PROMPT_BLOCKED
)
8587 target_terminal::ours_for_output ();
8588 printf_filtered (_("No unwaited-for children left.\n"));
8592 /* Note: this depends on the update_thread_list call above. */
8593 maybe_remove_breakpoints ();
8595 /* If an auto-display called a function and that got a signal,
8596 delete that auto-display to avoid an infinite recursion. */
8598 if (stopped_by_random_signal
)
8599 disable_current_display ();
8601 SWITCH_THRU_ALL_UIS ()
8603 async_enable_stdin ();
8606 /* Let the user/frontend see the threads as stopped. */
8607 maybe_finish_thread_state
.reset ();
8609 /* Select innermost stack frame - i.e., current frame is frame 0,
8610 and current location is based on that. Handle the case where the
8611 dummy call is returning after being stopped. E.g. the dummy call
8612 previously hit a breakpoint. (If the dummy call returns
8613 normally, we won't reach here.) Do this before the stop hook is
8614 run, so that it doesn't get to see the temporary dummy frame,
8615 which is not where we'll present the stop. */
8616 if (has_stack_frames ())
8618 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
8620 /* Pop the empty frame that contains the stack dummy. This
8621 also restores inferior state prior to the call (struct
8622 infcall_suspend_state). */
8623 struct frame_info
*frame
= get_current_frame ();
8625 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
8627 /* frame_pop calls reinit_frame_cache as the last thing it
8628 does which means there's now no selected frame. */
8631 select_frame (get_current_frame ());
8633 /* Set the current source location. */
8634 set_current_sal_from_frame (get_current_frame ());
8637 /* Look up the hook_stop and run it (CLI internally handles problem
8638 of stop_command's pre-hook not existing). */
8639 if (stop_command
!= NULL
)
8641 stop_context saved_context
;
8645 execute_cmd_pre_hook (stop_command
);
8647 catch (const gdb_exception
&ex
)
8649 exception_fprintf (gdb_stderr
, ex
,
8650 "Error while running hook_stop:\n");
8653 /* If the stop hook resumes the target, then there's no point in
8654 trying to notify about the previous stop; its context is
8655 gone. Likewise if the command switches thread or inferior --
8656 the observers would print a stop for the wrong
8658 if (saved_context
.changed ())
8662 /* Notify observers about the stop. This is where the interpreters
8663 print the stop event. */
8664 if (inferior_ptid
!= null_ptid
)
8665 gdb::observers::normal_stop
.notify (inferior_thread ()->control
.stop_bpstat
,
8668 gdb::observers::normal_stop
.notify (NULL
, stop_print_frame
);
8670 annotate_stopped ();
8672 if (target_has_execution ())
8674 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
8675 && last
.kind
!= TARGET_WAITKIND_EXITED
8676 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8677 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8678 Delete any breakpoint that is to be deleted at the next stop. */
8679 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
8682 /* Try to get rid of automatically added inferiors that are no
8683 longer needed. Keeping those around slows down things linearly.
8684 Note that this never removes the current inferior. */
8691 signal_stop_state (int signo
)
8693 return signal_stop
[signo
];
8697 signal_print_state (int signo
)
8699 return signal_print
[signo
];
8703 signal_pass_state (int signo
)
8705 return signal_program
[signo
];
8709 signal_cache_update (int signo
)
8713 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
8714 signal_cache_update (signo
);
8719 signal_pass
[signo
] = (signal_stop
[signo
] == 0
8720 && signal_print
[signo
] == 0
8721 && signal_program
[signo
] == 1
8722 && signal_catch
[signo
] == 0);
8726 signal_stop_update (int signo
, int state
)
8728 int ret
= signal_stop
[signo
];
8730 signal_stop
[signo
] = state
;
8731 signal_cache_update (signo
);
8736 signal_print_update (int signo
, int state
)
8738 int ret
= signal_print
[signo
];
8740 signal_print
[signo
] = state
;
8741 signal_cache_update (signo
);
8746 signal_pass_update (int signo
, int state
)
8748 int ret
= signal_program
[signo
];
8750 signal_program
[signo
] = state
;
8751 signal_cache_update (signo
);
8755 /* Update the global 'signal_catch' from INFO and notify the
8759 signal_catch_update (const unsigned int *info
)
8763 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
8764 signal_catch
[i
] = info
[i
] > 0;
8765 signal_cache_update (-1);
8766 target_pass_signals (signal_pass
);
8770 sig_print_header (void)
8772 printf_filtered (_("Signal Stop\tPrint\tPass "
8773 "to program\tDescription\n"));
8777 sig_print_info (enum gdb_signal oursig
)
8779 const char *name
= gdb_signal_to_name (oursig
);
8780 int name_padding
= 13 - strlen (name
);
8782 if (name_padding
<= 0)
8785 printf_filtered ("%s", name
);
8786 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
8787 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
8788 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
8789 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
8790 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
8793 /* Specify how various signals in the inferior should be handled. */
8796 handle_command (const char *args
, int from_tty
)
8798 int digits
, wordlen
;
8799 int sigfirst
, siglast
;
8800 enum gdb_signal oursig
;
8805 error_no_arg (_("signal to handle"));
8808 /* Allocate and zero an array of flags for which signals to handle. */
8810 const size_t nsigs
= GDB_SIGNAL_LAST
;
8811 unsigned char sigs
[nsigs
] {};
8813 /* Break the command line up into args. */
8815 gdb_argv
built_argv (args
);
8817 /* Walk through the args, looking for signal oursigs, signal names, and
8818 actions. Signal numbers and signal names may be interspersed with
8819 actions, with the actions being performed for all signals cumulatively
8820 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8822 for (char *arg
: built_argv
)
8824 wordlen
= strlen (arg
);
8825 for (digits
= 0; isdigit (arg
[digits
]); digits
++)
8829 sigfirst
= siglast
= -1;
8831 if (wordlen
>= 1 && !strncmp (arg
, "all", wordlen
))
8833 /* Apply action to all signals except those used by the
8834 debugger. Silently skip those. */
8837 siglast
= nsigs
- 1;
8839 else if (wordlen
>= 1 && !strncmp (arg
, "stop", wordlen
))
8841 SET_SIGS (nsigs
, sigs
, signal_stop
);
8842 SET_SIGS (nsigs
, sigs
, signal_print
);
8844 else if (wordlen
>= 1 && !strncmp (arg
, "ignore", wordlen
))
8846 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8848 else if (wordlen
>= 2 && !strncmp (arg
, "print", wordlen
))
8850 SET_SIGS (nsigs
, sigs
, signal_print
);
8852 else if (wordlen
>= 2 && !strncmp (arg
, "pass", wordlen
))
8854 SET_SIGS (nsigs
, sigs
, signal_program
);
8856 else if (wordlen
>= 3 && !strncmp (arg
, "nostop", wordlen
))
8858 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8860 else if (wordlen
>= 3 && !strncmp (arg
, "noignore", wordlen
))
8862 SET_SIGS (nsigs
, sigs
, signal_program
);
8864 else if (wordlen
>= 4 && !strncmp (arg
, "noprint", wordlen
))
8866 UNSET_SIGS (nsigs
, sigs
, signal_print
);
8867 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8869 else if (wordlen
>= 4 && !strncmp (arg
, "nopass", wordlen
))
8871 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8873 else if (digits
> 0)
8875 /* It is numeric. The numeric signal refers to our own
8876 internal signal numbering from target.h, not to host/target
8877 signal number. This is a feature; users really should be
8878 using symbolic names anyway, and the common ones like
8879 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8881 sigfirst
= siglast
= (int)
8882 gdb_signal_from_command (atoi (arg
));
8883 if (arg
[digits
] == '-')
8886 gdb_signal_from_command (atoi (arg
+ digits
+ 1));
8888 if (sigfirst
> siglast
)
8890 /* Bet he didn't figure we'd think of this case... */
8891 std::swap (sigfirst
, siglast
);
8896 oursig
= gdb_signal_from_name (arg
);
8897 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
8899 sigfirst
= siglast
= (int) oursig
;
8903 /* Not a number and not a recognized flag word => complain. */
8904 error (_("Unrecognized or ambiguous flag word: \"%s\"."), arg
);
8908 /* If any signal numbers or symbol names were found, set flags for
8909 which signals to apply actions to. */
8911 for (int signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
8913 switch ((enum gdb_signal
) signum
)
8915 case GDB_SIGNAL_TRAP
:
8916 case GDB_SIGNAL_INT
:
8917 if (!allsigs
&& !sigs
[signum
])
8919 if (query (_("%s is used by the debugger.\n\
8920 Are you sure you want to change it? "),
8921 gdb_signal_to_name ((enum gdb_signal
) signum
)))
8926 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8930 case GDB_SIGNAL_DEFAULT
:
8931 case GDB_SIGNAL_UNKNOWN
:
8932 /* Make sure that "all" doesn't print these. */
8941 for (int signum
= 0; signum
< nsigs
; signum
++)
8944 signal_cache_update (-1);
8945 target_pass_signals (signal_pass
);
8946 target_program_signals (signal_program
);
8950 /* Show the results. */
8951 sig_print_header ();
8952 for (; signum
< nsigs
; signum
++)
8954 sig_print_info ((enum gdb_signal
) signum
);
8961 /* Complete the "handle" command. */
8964 handle_completer (struct cmd_list_element
*ignore
,
8965 completion_tracker
&tracker
,
8966 const char *text
, const char *word
)
8968 static const char * const keywords
[] =
8982 signal_completer (ignore
, tracker
, text
, word
);
8983 complete_on_enum (tracker
, keywords
, word
, word
);
8987 gdb_signal_from_command (int num
)
8989 if (num
>= 1 && num
<= 15)
8990 return (enum gdb_signal
) num
;
8991 error (_("Only signals 1-15 are valid as numeric signals.\n\
8992 Use \"info signals\" for a list of symbolic signals."));
8995 /* Print current contents of the tables set by the handle command.
8996 It is possible we should just be printing signals actually used
8997 by the current target (but for things to work right when switching
8998 targets, all signals should be in the signal tables). */
9001 info_signals_command (const char *signum_exp
, int from_tty
)
9003 enum gdb_signal oursig
;
9005 sig_print_header ();
9009 /* First see if this is a symbol name. */
9010 oursig
= gdb_signal_from_name (signum_exp
);
9011 if (oursig
== GDB_SIGNAL_UNKNOWN
)
9013 /* No, try numeric. */
9015 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
9017 sig_print_info (oursig
);
9021 printf_filtered ("\n");
9022 /* These ugly casts brought to you by the native VAX compiler. */
9023 for (oursig
= GDB_SIGNAL_FIRST
;
9024 (int) oursig
< (int) GDB_SIGNAL_LAST
;
9025 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
9029 if (oursig
!= GDB_SIGNAL_UNKNOWN
9030 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
9031 sig_print_info (oursig
);
9034 printf_filtered (_("\nUse the \"handle\" command "
9035 "to change these tables.\n"));
9038 /* The $_siginfo convenience variable is a bit special. We don't know
9039 for sure the type of the value until we actually have a chance to
9040 fetch the data. The type can change depending on gdbarch, so it is
9041 also dependent on which thread you have selected.
9043 1. making $_siginfo be an internalvar that creates a new value on
9046 2. making the value of $_siginfo be an lval_computed value. */
9048 /* This function implements the lval_computed support for reading a
9052 siginfo_value_read (struct value
*v
)
9054 LONGEST transferred
;
9056 /* If we can access registers, so can we access $_siginfo. Likewise
9058 validate_registers_access ();
9061 target_read (current_inferior ()->top_target (),
9062 TARGET_OBJECT_SIGNAL_INFO
,
9064 value_contents_all_raw (v
),
9066 TYPE_LENGTH (value_type (v
)));
9068 if (transferred
!= TYPE_LENGTH (value_type (v
)))
9069 error (_("Unable to read siginfo"));
9072 /* This function implements the lval_computed support for writing a
9076 siginfo_value_write (struct value
*v
, struct value
*fromval
)
9078 LONGEST transferred
;
9080 /* If we can access registers, so can we access $_siginfo. Likewise
9082 validate_registers_access ();
9084 transferred
= target_write (current_inferior ()->top_target (),
9085 TARGET_OBJECT_SIGNAL_INFO
,
9087 value_contents_all_raw (fromval
),
9089 TYPE_LENGTH (value_type (fromval
)));
9091 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
9092 error (_("Unable to write siginfo"));
9095 static const struct lval_funcs siginfo_value_funcs
=
9101 /* Return a new value with the correct type for the siginfo object of
9102 the current thread using architecture GDBARCH. Return a void value
9103 if there's no object available. */
9105 static struct value
*
9106 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
9109 if (target_has_stack ()
9110 && inferior_ptid
!= null_ptid
9111 && gdbarch_get_siginfo_type_p (gdbarch
))
9113 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
9115 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
9118 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
9122 /* infcall_suspend_state contains state about the program itself like its
9123 registers and any signal it received when it last stopped.
9124 This state must be restored regardless of how the inferior function call
9125 ends (either successfully, or after it hits a breakpoint or signal)
9126 if the program is to properly continue where it left off. */
9128 class infcall_suspend_state
9131 /* Capture state from GDBARCH, TP, and REGCACHE that must be restored
9132 once the inferior function call has finished. */
9133 infcall_suspend_state (struct gdbarch
*gdbarch
,
9134 const struct thread_info
*tp
,
9135 struct regcache
*regcache
)
9136 : m_thread_suspend (tp
->suspend
),
9137 m_registers (new readonly_detached_regcache (*regcache
))
9139 gdb::unique_xmalloc_ptr
<gdb_byte
> siginfo_data
;
9141 if (gdbarch_get_siginfo_type_p (gdbarch
))
9143 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
9144 size_t len
= TYPE_LENGTH (type
);
9146 siginfo_data
.reset ((gdb_byte
*) xmalloc (len
));
9148 if (target_read (current_inferior ()->top_target (),
9149 TARGET_OBJECT_SIGNAL_INFO
, NULL
,
9150 siginfo_data
.get (), 0, len
) != len
)
9152 /* Errors ignored. */
9153 siginfo_data
.reset (nullptr);
9159 m_siginfo_gdbarch
= gdbarch
;
9160 m_siginfo_data
= std::move (siginfo_data
);
9164 /* Return a pointer to the stored register state. */
9166 readonly_detached_regcache
*registers () const
9168 return m_registers
.get ();
9171 /* Restores the stored state into GDBARCH, TP, and REGCACHE. */
9173 void restore (struct gdbarch
*gdbarch
,
9174 struct thread_info
*tp
,
9175 struct regcache
*regcache
) const
9177 tp
->suspend
= m_thread_suspend
;
9179 if (m_siginfo_gdbarch
== gdbarch
)
9181 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
9183 /* Errors ignored. */
9184 target_write (current_inferior ()->top_target (),
9185 TARGET_OBJECT_SIGNAL_INFO
, NULL
,
9186 m_siginfo_data
.get (), 0, TYPE_LENGTH (type
));
9189 /* The inferior can be gone if the user types "print exit(0)"
9190 (and perhaps other times). */
9191 if (target_has_execution ())
9192 /* NB: The register write goes through to the target. */
9193 regcache
->restore (registers ());
9197 /* How the current thread stopped before the inferior function call was
9199 struct thread_suspend_state m_thread_suspend
;
9201 /* The registers before the inferior function call was executed. */
9202 std::unique_ptr
<readonly_detached_regcache
> m_registers
;
9204 /* Format of SIGINFO_DATA or NULL if it is not present. */
9205 struct gdbarch
*m_siginfo_gdbarch
= nullptr;
9207 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
9208 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
9209 content would be invalid. */
9210 gdb::unique_xmalloc_ptr
<gdb_byte
> m_siginfo_data
;
9213 infcall_suspend_state_up
9214 save_infcall_suspend_state ()
9216 struct thread_info
*tp
= inferior_thread ();
9217 struct regcache
*regcache
= get_current_regcache ();
9218 struct gdbarch
*gdbarch
= regcache
->arch ();
9220 infcall_suspend_state_up inf_state
9221 (new struct infcall_suspend_state (gdbarch
, tp
, regcache
));
9223 /* Having saved the current state, adjust the thread state, discarding
9224 any stop signal information. The stop signal is not useful when
9225 starting an inferior function call, and run_inferior_call will not use
9226 the signal due to its `proceed' call with GDB_SIGNAL_0. */
9227 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
9232 /* Restore inferior session state to INF_STATE. */
9235 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
9237 struct thread_info
*tp
= inferior_thread ();
9238 struct regcache
*regcache
= get_current_regcache ();
9239 struct gdbarch
*gdbarch
= regcache
->arch ();
9241 inf_state
->restore (gdbarch
, tp
, regcache
);
9242 discard_infcall_suspend_state (inf_state
);
9246 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
9251 readonly_detached_regcache
*
9252 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
9254 return inf_state
->registers ();
9257 /* infcall_control_state contains state regarding gdb's control of the
9258 inferior itself like stepping control. It also contains session state like
9259 the user's currently selected frame. */
9261 struct infcall_control_state
9263 struct thread_control_state thread_control
;
9264 struct inferior_control_state inferior_control
;
9267 enum stop_stack_kind stop_stack_dummy
= STOP_NONE
;
9268 int stopped_by_random_signal
= 0;
9270 /* ID and level of the selected frame when the inferior function
9272 struct frame_id selected_frame_id
{};
9273 int selected_frame_level
= -1;
9276 /* Save all of the information associated with the inferior<==>gdb
9279 infcall_control_state_up
9280 save_infcall_control_state ()
9282 infcall_control_state_up
inf_status (new struct infcall_control_state
);
9283 struct thread_info
*tp
= inferior_thread ();
9284 struct inferior
*inf
= current_inferior ();
9286 inf_status
->thread_control
= tp
->control
;
9287 inf_status
->inferior_control
= inf
->control
;
9289 tp
->control
.step_resume_breakpoint
= NULL
;
9290 tp
->control
.exception_resume_breakpoint
= NULL
;
9292 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
9293 chain. If caller's caller is walking the chain, they'll be happier if we
9294 hand them back the original chain when restore_infcall_control_state is
9296 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
9299 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
9300 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
9302 save_selected_frame (&inf_status
->selected_frame_id
,
9303 &inf_status
->selected_frame_level
);
9308 /* Restore inferior session state to INF_STATUS. */
9311 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
9313 struct thread_info
*tp
= inferior_thread ();
9314 struct inferior
*inf
= current_inferior ();
9316 if (tp
->control
.step_resume_breakpoint
)
9317 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
9319 if (tp
->control
.exception_resume_breakpoint
)
9320 tp
->control
.exception_resume_breakpoint
->disposition
9321 = disp_del_at_next_stop
;
9323 /* Handle the bpstat_copy of the chain. */
9324 bpstat_clear (&tp
->control
.stop_bpstat
);
9326 tp
->control
= inf_status
->thread_control
;
9327 inf
->control
= inf_status
->inferior_control
;
9330 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
9331 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
9333 if (target_has_stack ())
9335 restore_selected_frame (inf_status
->selected_frame_id
,
9336 inf_status
->selected_frame_level
);
9343 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
9345 if (inf_status
->thread_control
.step_resume_breakpoint
)
9346 inf_status
->thread_control
.step_resume_breakpoint
->disposition
9347 = disp_del_at_next_stop
;
9349 if (inf_status
->thread_control
.exception_resume_breakpoint
)
9350 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
9351 = disp_del_at_next_stop
;
9353 /* See save_infcall_control_state for info on stop_bpstat. */
9354 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
9362 clear_exit_convenience_vars (void)
9364 clear_internalvar (lookup_internalvar ("_exitsignal"));
9365 clear_internalvar (lookup_internalvar ("_exitcode"));
9369 /* User interface for reverse debugging:
9370 Set exec-direction / show exec-direction commands
9371 (returns error unless target implements to_set_exec_direction method). */
9373 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
9374 static const char exec_forward
[] = "forward";
9375 static const char exec_reverse
[] = "reverse";
9376 static const char *exec_direction
= exec_forward
;
9377 static const char *const exec_direction_names
[] = {
9384 set_exec_direction_func (const char *args
, int from_tty
,
9385 struct cmd_list_element
*cmd
)
9387 if (target_can_execute_reverse ())
9389 if (!strcmp (exec_direction
, exec_forward
))
9390 execution_direction
= EXEC_FORWARD
;
9391 else if (!strcmp (exec_direction
, exec_reverse
))
9392 execution_direction
= EXEC_REVERSE
;
9396 exec_direction
= exec_forward
;
9397 error (_("Target does not support this operation."));
9402 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
9403 struct cmd_list_element
*cmd
, const char *value
)
9405 switch (execution_direction
) {
9407 fprintf_filtered (out
, _("Forward.\n"));
9410 fprintf_filtered (out
, _("Reverse.\n"));
9413 internal_error (__FILE__
, __LINE__
,
9414 _("bogus execution_direction value: %d"),
9415 (int) execution_direction
);
9420 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
9421 struct cmd_list_element
*c
, const char *value
)
9423 fprintf_filtered (file
, _("Resuming the execution of threads "
9424 "of all processes is %s.\n"), value
);
9427 /* Implementation of `siginfo' variable. */
9429 static const struct internalvar_funcs siginfo_funcs
=
9436 /* Callback for infrun's target events source. This is marked when a
9437 thread has a pending status to process. */
9440 infrun_async_inferior_event_handler (gdb_client_data data
)
9442 clear_async_event_handler (infrun_async_inferior_event_token
);
9443 inferior_event_handler (INF_REG_EVENT
);
9450 /* Verify that when two threads with the same ptid exist (from two different
9451 targets) and one of them changes ptid, we only update inferior_ptid if
9452 it is appropriate. */
9455 infrun_thread_ptid_changed ()
9457 gdbarch
*arch
= current_inferior ()->gdbarch
;
9459 /* The thread which inferior_ptid represents changes ptid. */
9461 scoped_restore_current_pspace_and_thread restore
;
9463 scoped_mock_context
<test_target_ops
> target1 (arch
);
9464 scoped_mock_context
<test_target_ops
> target2 (arch
);
9466 ptid_t
old_ptid (111, 222);
9467 ptid_t
new_ptid (111, 333);
9469 target1
.mock_inferior
.pid
= old_ptid
.pid ();
9470 target1
.mock_thread
.ptid
= old_ptid
;
9471 target2
.mock_inferior
.pid
= old_ptid
.pid ();
9472 target2
.mock_thread
.ptid
= old_ptid
;
9474 auto restore_inferior_ptid
= make_scoped_restore (&inferior_ptid
, old_ptid
);
9475 set_current_inferior (&target1
.mock_inferior
);
9477 thread_change_ptid (&target1
.mock_target
, old_ptid
, new_ptid
);
9479 gdb_assert (inferior_ptid
== new_ptid
);
9482 /* A thread with the same ptid as inferior_ptid, but from another target,
9485 scoped_restore_current_pspace_and_thread restore
;
9487 scoped_mock_context
<test_target_ops
> target1 (arch
);
9488 scoped_mock_context
<test_target_ops
> target2 (arch
);
9490 ptid_t
old_ptid (111, 222);
9491 ptid_t
new_ptid (111, 333);
9493 target1
.mock_inferior
.pid
= old_ptid
.pid ();
9494 target1
.mock_thread
.ptid
= old_ptid
;
9495 target2
.mock_inferior
.pid
= old_ptid
.pid ();
9496 target2
.mock_thread
.ptid
= old_ptid
;
9498 auto restore_inferior_ptid
= make_scoped_restore (&inferior_ptid
, old_ptid
);
9499 set_current_inferior (&target2
.mock_inferior
);
9501 thread_change_ptid (&target1
.mock_target
, old_ptid
, new_ptid
);
9503 gdb_assert (inferior_ptid
== old_ptid
);
9507 } /* namespace selftests */
9509 #endif /* GDB_SELF_TEST */
9511 void _initialize_infrun ();
9513 _initialize_infrun ()
9515 struct cmd_list_element
*c
;
9517 /* Register extra event sources in the event loop. */
9518 infrun_async_inferior_event_token
9519 = create_async_event_handler (infrun_async_inferior_event_handler
, NULL
,
9522 cmd_list_element
*info_signals_cmd
9523 = add_info ("signals", info_signals_command
, _("\
9524 What debugger does when program gets various signals.\n\
9525 Specify a signal as argument to print info on that signal only."));
9526 add_info_alias ("handle", info_signals_cmd
, 0);
9528 c
= add_com ("handle", class_run
, handle_command
, _("\
9529 Specify how to handle signals.\n\
9530 Usage: handle SIGNAL [ACTIONS]\n\
9531 Args are signals and actions to apply to those signals.\n\
9532 If no actions are specified, the current settings for the specified signals\n\
9533 will be displayed instead.\n\
9535 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
9536 from 1-15 are allowed for compatibility with old versions of GDB.\n\
9537 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
9538 The special arg \"all\" is recognized to mean all signals except those\n\
9539 used by the debugger, typically SIGTRAP and SIGINT.\n\
9541 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
9542 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
9543 Stop means reenter debugger if this signal happens (implies print).\n\
9544 Print means print a message if this signal happens.\n\
9545 Pass means let program see this signal; otherwise program doesn't know.\n\
9546 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
9547 Pass and Stop may be combined.\n\
9549 Multiple signals may be specified. Signal numbers and signal names\n\
9550 may be interspersed with actions, with the actions being performed for\n\
9551 all signals cumulatively specified."));
9552 set_cmd_completer (c
, handle_completer
);
9555 stop_command
= add_cmd ("stop", class_obscure
,
9556 not_just_help_class_command
, _("\
9557 There is no `stop' command, but you can set a hook on `stop'.\n\
9558 This allows you to set a list of commands to be run each time execution\n\
9559 of the program stops."), &cmdlist
);
9561 add_setshow_boolean_cmd
9562 ("infrun", class_maintenance
, &debug_infrun
,
9563 _("Set inferior debugging."),
9564 _("Show inferior debugging."),
9565 _("When non-zero, inferior specific debugging is enabled."),
9566 NULL
, show_debug_infrun
, &setdebuglist
, &showdebuglist
);
9568 add_setshow_boolean_cmd ("non-stop", no_class
,
9570 Set whether gdb controls the inferior in non-stop mode."), _("\
9571 Show whether gdb controls the inferior in non-stop mode."), _("\
9572 When debugging a multi-threaded program and this setting is\n\
9573 off (the default, also called all-stop mode), when one thread stops\n\
9574 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9575 all other threads in the program while you interact with the thread of\n\
9576 interest. When you continue or step a thread, you can allow the other\n\
9577 threads to run, or have them remain stopped, but while you inspect any\n\
9578 thread's state, all threads stop.\n\
9580 In non-stop mode, when one thread stops, other threads can continue\n\
9581 to run freely. You'll be able to step each thread independently,\n\
9582 leave it stopped or free to run as needed."),
9588 for (size_t i
= 0; i
< GDB_SIGNAL_LAST
; i
++)
9591 signal_print
[i
] = 1;
9592 signal_program
[i
] = 1;
9593 signal_catch
[i
] = 0;
9596 /* Signals caused by debugger's own actions should not be given to
9597 the program afterwards.
9599 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9600 explicitly specifies that it should be delivered to the target
9601 program. Typically, that would occur when a user is debugging a
9602 target monitor on a simulator: the target monitor sets a
9603 breakpoint; the simulator encounters this breakpoint and halts
9604 the simulation handing control to GDB; GDB, noting that the stop
9605 address doesn't map to any known breakpoint, returns control back
9606 to the simulator; the simulator then delivers the hardware
9607 equivalent of a GDB_SIGNAL_TRAP to the program being
9609 signal_program
[GDB_SIGNAL_TRAP
] = 0;
9610 signal_program
[GDB_SIGNAL_INT
] = 0;
9612 /* Signals that are not errors should not normally enter the debugger. */
9613 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
9614 signal_print
[GDB_SIGNAL_ALRM
] = 0;
9615 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
9616 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
9617 signal_stop
[GDB_SIGNAL_PROF
] = 0;
9618 signal_print
[GDB_SIGNAL_PROF
] = 0;
9619 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
9620 signal_print
[GDB_SIGNAL_CHLD
] = 0;
9621 signal_stop
[GDB_SIGNAL_IO
] = 0;
9622 signal_print
[GDB_SIGNAL_IO
] = 0;
9623 signal_stop
[GDB_SIGNAL_POLL
] = 0;
9624 signal_print
[GDB_SIGNAL_POLL
] = 0;
9625 signal_stop
[GDB_SIGNAL_URG
] = 0;
9626 signal_print
[GDB_SIGNAL_URG
] = 0;
9627 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
9628 signal_print
[GDB_SIGNAL_WINCH
] = 0;
9629 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
9630 signal_print
[GDB_SIGNAL_PRIO
] = 0;
9632 /* These signals are used internally by user-level thread
9633 implementations. (See signal(5) on Solaris.) Like the above
9634 signals, a healthy program receives and handles them as part of
9635 its normal operation. */
9636 signal_stop
[GDB_SIGNAL_LWP
] = 0;
9637 signal_print
[GDB_SIGNAL_LWP
] = 0;
9638 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
9639 signal_print
[GDB_SIGNAL_WAITING
] = 0;
9640 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
9641 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
9642 signal_stop
[GDB_SIGNAL_LIBRT
] = 0;
9643 signal_print
[GDB_SIGNAL_LIBRT
] = 0;
9645 /* Update cached state. */
9646 signal_cache_update (-1);
9648 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
9649 &stop_on_solib_events
, _("\
9650 Set stopping for shared library events."), _("\
9651 Show stopping for shared library events."), _("\
9652 If nonzero, gdb will give control to the user when the dynamic linker\n\
9653 notifies gdb of shared library events. The most common event of interest\n\
9654 to the user would be loading/unloading of a new library."),
9655 set_stop_on_solib_events
,
9656 show_stop_on_solib_events
,
9657 &setlist
, &showlist
);
9659 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
9660 follow_fork_mode_kind_names
,
9661 &follow_fork_mode_string
, _("\
9662 Set debugger response to a program call of fork or vfork."), _("\
9663 Show debugger response to a program call of fork or vfork."), _("\
9664 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9665 parent - the original process is debugged after a fork\n\
9666 child - the new process is debugged after a fork\n\
9667 The unfollowed process will continue to run.\n\
9668 By default, the debugger will follow the parent process."),
9670 show_follow_fork_mode_string
,
9671 &setlist
, &showlist
);
9673 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
9674 follow_exec_mode_names
,
9675 &follow_exec_mode_string
, _("\
9676 Set debugger response to a program call of exec."), _("\
9677 Show debugger response to a program call of exec."), _("\
9678 An exec call replaces the program image of a process.\n\
9680 follow-exec-mode can be:\n\
9682 new - the debugger creates a new inferior and rebinds the process\n\
9683 to this new inferior. The program the process was running before\n\
9684 the exec call can be restarted afterwards by restarting the original\n\
9687 same - the debugger keeps the process bound to the same inferior.\n\
9688 The new executable image replaces the previous executable loaded in\n\
9689 the inferior. Restarting the inferior after the exec call restarts\n\
9690 the executable the process was running after the exec call.\n\
9692 By default, the debugger will use the same inferior."),
9694 show_follow_exec_mode_string
,
9695 &setlist
, &showlist
);
9697 add_setshow_enum_cmd ("scheduler-locking", class_run
,
9698 scheduler_enums
, &scheduler_mode
, _("\
9699 Set mode for locking scheduler during execution."), _("\
9700 Show mode for locking scheduler during execution."), _("\
9701 off == no locking (threads may preempt at any time)\n\
9702 on == full locking (no thread except the current thread may run)\n\
9703 This applies to both normal execution and replay mode.\n\
9704 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9705 In this mode, other threads may run during other commands.\n\
9706 This applies to both normal execution and replay mode.\n\
9707 replay == scheduler locked in replay mode and unlocked during normal execution."),
9708 set_schedlock_func
, /* traps on target vector */
9709 show_scheduler_mode
,
9710 &setlist
, &showlist
);
9712 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
9713 Set mode for resuming threads of all processes."), _("\
9714 Show mode for resuming threads of all processes."), _("\
9715 When on, execution commands (such as 'continue' or 'next') resume all\n\
9716 threads of all processes. When off (which is the default), execution\n\
9717 commands only resume the threads of the current process. The set of\n\
9718 threads that are resumed is further refined by the scheduler-locking\n\
9719 mode (see help set scheduler-locking)."),
9721 show_schedule_multiple
,
9722 &setlist
, &showlist
);
9724 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
9725 Set mode of the step operation."), _("\
9726 Show mode of the step operation."), _("\
9727 When set, doing a step over a function without debug line information\n\
9728 will stop at the first instruction of that function. Otherwise, the\n\
9729 function is skipped and the step command stops at a different source line."),
9731 show_step_stop_if_no_debug
,
9732 &setlist
, &showlist
);
9734 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
9735 &can_use_displaced_stepping
, _("\
9736 Set debugger's willingness to use displaced stepping."), _("\
9737 Show debugger's willingness to use displaced stepping."), _("\
9738 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9739 supported by the target architecture. If off, gdb will not use displaced\n\
9740 stepping to step over breakpoints, even if such is supported by the target\n\
9741 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9742 if the target architecture supports it and non-stop mode is active, but will not\n\
9743 use it in all-stop mode (see help set non-stop)."),
9745 show_can_use_displaced_stepping
,
9746 &setlist
, &showlist
);
9748 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
9749 &exec_direction
, _("Set direction of execution.\n\
9750 Options are 'forward' or 'reverse'."),
9751 _("Show direction of execution (forward/reverse)."),
9752 _("Tells gdb whether to execute forward or backward."),
9753 set_exec_direction_func
, show_exec_direction_func
,
9754 &setlist
, &showlist
);
9756 /* Set/show detach-on-fork: user-settable mode. */
9758 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
9759 Set whether gdb will detach the child of a fork."), _("\
9760 Show whether gdb will detach the child of a fork."), _("\
9761 Tells gdb whether to detach the child of a fork."),
9762 NULL
, NULL
, &setlist
, &showlist
);
9764 /* Set/show disable address space randomization mode. */
9766 add_setshow_boolean_cmd ("disable-randomization", class_support
,
9767 &disable_randomization
, _("\
9768 Set disabling of debuggee's virtual address space randomization."), _("\
9769 Show disabling of debuggee's virtual address space randomization."), _("\
9770 When this mode is on (which is the default), randomization of the virtual\n\
9771 address space is disabled. Standalone programs run with the randomization\n\
9772 enabled by default on some platforms."),
9773 &set_disable_randomization
,
9774 &show_disable_randomization
,
9775 &setlist
, &showlist
);
9777 /* ptid initializations */
9778 inferior_ptid
= null_ptid
;
9779 target_last_wait_ptid
= minus_one_ptid
;
9781 gdb::observers::thread_ptid_changed
.attach (infrun_thread_ptid_changed
,
9783 gdb::observers::thread_stop_requested
.attach (infrun_thread_stop_requested
,
9785 gdb::observers::thread_exit
.attach (infrun_thread_thread_exit
, "infrun");
9786 gdb::observers::inferior_exit
.attach (infrun_inferior_exit
, "infrun");
9787 gdb::observers::inferior_execd
.attach (infrun_inferior_execd
, "infrun");
9789 /* Explicitly create without lookup, since that tries to create a
9790 value with a void typed value, and when we get here, gdbarch
9791 isn't initialized yet. At this point, we're quite sure there
9792 isn't another convenience variable of the same name. */
9793 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
9795 add_setshow_boolean_cmd ("observer", no_class
,
9796 &observer_mode_1
, _("\
9797 Set whether gdb controls the inferior in observer mode."), _("\
9798 Show whether gdb controls the inferior in observer mode."), _("\
9799 In observer mode, GDB can get data from the inferior, but not\n\
9800 affect its execution. Registers and memory may not be changed,\n\
9801 breakpoints may not be set, and the program cannot be interrupted\n\
9809 selftests::register_test ("infrun_thread_ptid_changed",
9810 selftests::infrun_thread_ptid_changed
);