1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2019 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/>. */
27 #include "breakpoint.h"
28 #include "common/gdb_wait.h"
31 #include "cli/cli-script.h"
33 #include "gdbthread.h"
41 #include "observable.h"
45 #include "dictionary.h"
47 #include "mi/mi-common.h"
48 #include "event-top.h"
50 #include "record-full.h"
51 #include "inline-frame.h"
53 #include "tracepoint.h"
54 #include "continuations.h"
59 #include "completer.h"
60 #include "target-descriptions.h"
61 #include "target-dcache.h"
64 #include "event-loop.h"
65 #include "thread-fsm.h"
66 #include "common/enum-flags.h"
67 #include "progspace-and-thread.h"
68 #include "common/gdb_optional.h"
69 #include "arch-utils.h"
70 #include "common/scope-exit.h"
71 #include "common/forward-scope-exit.h"
73 /* Prototypes for local functions */
75 static void sig_print_info (enum gdb_signal
);
77 static void sig_print_header (void);
79 static int follow_fork (void);
81 static int follow_fork_inferior (int follow_child
, int detach_fork
);
83 static void follow_inferior_reset_breakpoints (void);
85 static int currently_stepping (struct thread_info
*tp
);
87 void nullify_last_target_wait_ptid (void);
89 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*);
91 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
93 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
95 static int maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
);
97 static void resume (gdb_signal sig
);
99 /* Asynchronous signal handler registered as event loop source for
100 when we have pending events ready to be passed to the core. */
101 static struct async_event_handler
*infrun_async_inferior_event_token
;
103 /* Stores whether infrun_async was previously enabled or disabled.
104 Starts off as -1, indicating "never enabled/disabled". */
105 static int infrun_is_async
= -1;
110 infrun_async (int enable
)
112 if (infrun_is_async
!= enable
)
114 infrun_is_async
= enable
;
117 fprintf_unfiltered (gdb_stdlog
,
118 "infrun: infrun_async(%d)\n",
122 mark_async_event_handler (infrun_async_inferior_event_token
);
124 clear_async_event_handler (infrun_async_inferior_event_token
);
131 mark_infrun_async_event_handler (void)
133 mark_async_event_handler (infrun_async_inferior_event_token
);
136 /* When set, stop the 'step' command if we enter a function which has
137 no line number information. The normal behavior is that we step
138 over such function. */
139 int step_stop_if_no_debug
= 0;
141 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
142 struct cmd_list_element
*c
, const char *value
)
144 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
147 /* proceed and normal_stop use this to notify the user when the
148 inferior stopped in a different thread than it had been running
151 static ptid_t previous_inferior_ptid
;
153 /* If set (default for legacy reasons), when following a fork, GDB
154 will detach from one of the fork branches, child or parent.
155 Exactly which branch is detached depends on 'set follow-fork-mode'
158 static int detach_fork
= 1;
160 int debug_displaced
= 0;
162 show_debug_displaced (struct ui_file
*file
, int from_tty
,
163 struct cmd_list_element
*c
, const char *value
)
165 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
168 unsigned int debug_infrun
= 0;
170 show_debug_infrun (struct ui_file
*file
, int from_tty
,
171 struct cmd_list_element
*c
, const char *value
)
173 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
177 /* Support for disabling address space randomization. */
179 int disable_randomization
= 1;
182 show_disable_randomization (struct ui_file
*file
, int from_tty
,
183 struct cmd_list_element
*c
, const char *value
)
185 if (target_supports_disable_randomization ())
186 fprintf_filtered (file
,
187 _("Disabling randomization of debuggee's "
188 "virtual address space is %s.\n"),
191 fputs_filtered (_("Disabling randomization of debuggee's "
192 "virtual address space is unsupported on\n"
193 "this platform.\n"), file
);
197 set_disable_randomization (const char *args
, int from_tty
,
198 struct cmd_list_element
*c
)
200 if (!target_supports_disable_randomization ())
201 error (_("Disabling randomization of debuggee's "
202 "virtual address space is unsupported on\n"
206 /* User interface for non-stop mode. */
209 static int non_stop_1
= 0;
212 set_non_stop (const char *args
, int from_tty
,
213 struct cmd_list_element
*c
)
215 if (target_has_execution
)
217 non_stop_1
= non_stop
;
218 error (_("Cannot change this setting while the inferior is running."));
221 non_stop
= non_stop_1
;
225 show_non_stop (struct ui_file
*file
, int from_tty
,
226 struct cmd_list_element
*c
, const char *value
)
228 fprintf_filtered (file
,
229 _("Controlling the inferior in non-stop mode is %s.\n"),
233 /* "Observer mode" is somewhat like a more extreme version of
234 non-stop, in which all GDB operations that might affect the
235 target's execution have been disabled. */
237 int observer_mode
= 0;
238 static int observer_mode_1
= 0;
241 set_observer_mode (const char *args
, int from_tty
,
242 struct cmd_list_element
*c
)
244 if (target_has_execution
)
246 observer_mode_1
= observer_mode
;
247 error (_("Cannot change this setting while the inferior is running."));
250 observer_mode
= observer_mode_1
;
252 may_write_registers
= !observer_mode
;
253 may_write_memory
= !observer_mode
;
254 may_insert_breakpoints
= !observer_mode
;
255 may_insert_tracepoints
= !observer_mode
;
256 /* We can insert fast tracepoints in or out of observer mode,
257 but enable them if we're going into this mode. */
259 may_insert_fast_tracepoints
= 1;
260 may_stop
= !observer_mode
;
261 update_target_permissions ();
263 /* Going *into* observer mode we must force non-stop, then
264 going out we leave it that way. */
267 pagination_enabled
= 0;
268 non_stop
= non_stop_1
= 1;
272 printf_filtered (_("Observer mode is now %s.\n"),
273 (observer_mode
? "on" : "off"));
277 show_observer_mode (struct ui_file
*file
, int from_tty
,
278 struct cmd_list_element
*c
, const char *value
)
280 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
283 /* This updates the value of observer mode based on changes in
284 permissions. Note that we are deliberately ignoring the values of
285 may-write-registers and may-write-memory, since the user may have
286 reason to enable these during a session, for instance to turn on a
287 debugging-related global. */
290 update_observer_mode (void)
294 newval
= (!may_insert_breakpoints
295 && !may_insert_tracepoints
296 && may_insert_fast_tracepoints
300 /* Let the user know if things change. */
301 if (newval
!= observer_mode
)
302 printf_filtered (_("Observer mode is now %s.\n"),
303 (newval
? "on" : "off"));
305 observer_mode
= observer_mode_1
= newval
;
308 /* Tables of how to react to signals; the user sets them. */
310 static unsigned char signal_stop
[GDB_SIGNAL_LAST
];
311 static unsigned char signal_print
[GDB_SIGNAL_LAST
];
312 static unsigned char signal_program
[GDB_SIGNAL_LAST
];
314 /* Table of signals that are registered with "catch signal". A
315 non-zero entry indicates that the signal is caught by some "catch
317 static unsigned char signal_catch
[GDB_SIGNAL_LAST
];
319 /* Table of signals that the target may silently handle.
320 This is automatically determined from the flags above,
321 and simply cached here. */
322 static unsigned char signal_pass
[GDB_SIGNAL_LAST
];
324 #define SET_SIGS(nsigs,sigs,flags) \
326 int signum = (nsigs); \
327 while (signum-- > 0) \
328 if ((sigs)[signum]) \
329 (flags)[signum] = 1; \
332 #define UNSET_SIGS(nsigs,sigs,flags) \
334 int signum = (nsigs); \
335 while (signum-- > 0) \
336 if ((sigs)[signum]) \
337 (flags)[signum] = 0; \
340 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
341 this function is to avoid exporting `signal_program'. */
344 update_signals_program_target (void)
346 target_program_signals (signal_program
);
349 /* Value to pass to target_resume() to cause all threads to resume. */
351 #define RESUME_ALL minus_one_ptid
353 /* Command list pointer for the "stop" placeholder. */
355 static struct cmd_list_element
*stop_command
;
357 /* Nonzero if we want to give control to the user when we're notified
358 of shared library events by the dynamic linker. */
359 int stop_on_solib_events
;
361 /* Enable or disable optional shared library event breakpoints
362 as appropriate when the above flag is changed. */
365 set_stop_on_solib_events (const char *args
,
366 int from_tty
, struct cmd_list_element
*c
)
368 update_solib_breakpoints ();
372 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
373 struct cmd_list_element
*c
, const char *value
)
375 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
379 /* Nonzero after stop if current stack frame should be printed. */
381 static int stop_print_frame
;
383 /* This is a cached copy of the pid/waitstatus of the last event
384 returned by target_wait()/deprecated_target_wait_hook(). This
385 information is returned by get_last_target_status(). */
386 static ptid_t target_last_wait_ptid
;
387 static struct target_waitstatus target_last_waitstatus
;
389 void init_thread_stepping_state (struct thread_info
*tss
);
391 static const char follow_fork_mode_child
[] = "child";
392 static const char follow_fork_mode_parent
[] = "parent";
394 static const char *const follow_fork_mode_kind_names
[] = {
395 follow_fork_mode_child
,
396 follow_fork_mode_parent
,
400 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
402 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
403 struct cmd_list_element
*c
, const char *value
)
405 fprintf_filtered (file
,
406 _("Debugger response to a program "
407 "call of fork or vfork is \"%s\".\n"),
412 /* Handle changes to the inferior list based on the type of fork,
413 which process is being followed, and whether the other process
414 should be detached. On entry inferior_ptid must be the ptid of
415 the fork parent. At return inferior_ptid is the ptid of the
416 followed inferior. */
419 follow_fork_inferior (int follow_child
, int detach_fork
)
422 ptid_t parent_ptid
, child_ptid
;
424 has_vforked
= (inferior_thread ()->pending_follow
.kind
425 == TARGET_WAITKIND_VFORKED
);
426 parent_ptid
= inferior_ptid
;
427 child_ptid
= inferior_thread ()->pending_follow
.value
.related_pid
;
430 && !non_stop
/* Non-stop always resumes both branches. */
431 && current_ui
->prompt_state
== PROMPT_BLOCKED
432 && !(follow_child
|| detach_fork
|| sched_multi
))
434 /* The parent stays blocked inside the vfork syscall until the
435 child execs or exits. If we don't let the child run, then
436 the parent stays blocked. If we're telling the parent to run
437 in the foreground, the user will not be able to ctrl-c to get
438 back the terminal, effectively hanging the debug session. */
439 fprintf_filtered (gdb_stderr
, _("\
440 Can not resume the parent process over vfork in the foreground while\n\
441 holding the child stopped. Try \"set detach-on-fork\" or \
442 \"set schedule-multiple\".\n"));
443 /* FIXME output string > 80 columns. */
449 /* Detach new forked process? */
452 /* Before detaching from the child, remove all breakpoints
453 from it. If we forked, then this has already been taken
454 care of by infrun.c. If we vforked however, any
455 breakpoint inserted in the parent is visible in the
456 child, even those added while stopped in a vfork
457 catchpoint. This will remove the breakpoints from the
458 parent also, but they'll be reinserted below. */
461 /* Keep breakpoints list in sync. */
462 remove_breakpoints_inf (current_inferior ());
465 if (print_inferior_events
)
467 /* Ensure that we have a process ptid. */
468 ptid_t process_ptid
= ptid_t (child_ptid
.pid ());
470 target_terminal::ours_for_output ();
471 fprintf_filtered (gdb_stdlog
,
472 _("[Detaching after %s from child %s]\n"),
473 has_vforked
? "vfork" : "fork",
474 target_pid_to_str (process_ptid
).c_str ());
479 struct inferior
*parent_inf
, *child_inf
;
481 /* Add process to GDB's tables. */
482 child_inf
= add_inferior (child_ptid
.pid ());
484 parent_inf
= current_inferior ();
485 child_inf
->attach_flag
= parent_inf
->attach_flag
;
486 copy_terminal_info (child_inf
, parent_inf
);
487 child_inf
->gdbarch
= parent_inf
->gdbarch
;
488 copy_inferior_target_desc_info (child_inf
, parent_inf
);
490 scoped_restore_current_pspace_and_thread restore_pspace_thread
;
492 inferior_ptid
= child_ptid
;
493 add_thread_silent (inferior_ptid
);
494 set_current_inferior (child_inf
);
495 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
497 /* If this is a vfork child, then the address-space is
498 shared with the parent. */
501 child_inf
->pspace
= parent_inf
->pspace
;
502 child_inf
->aspace
= parent_inf
->aspace
;
504 /* The parent will be frozen until the child is done
505 with the shared region. Keep track of the
507 child_inf
->vfork_parent
= parent_inf
;
508 child_inf
->pending_detach
= 0;
509 parent_inf
->vfork_child
= child_inf
;
510 parent_inf
->pending_detach
= 0;
514 child_inf
->aspace
= new_address_space ();
515 child_inf
->pspace
= new program_space (child_inf
->aspace
);
516 child_inf
->removable
= 1;
517 set_current_program_space (child_inf
->pspace
);
518 clone_program_space (child_inf
->pspace
, parent_inf
->pspace
);
520 /* Let the shared library layer (e.g., solib-svr4) learn
521 about this new process, relocate the cloned exec, pull
522 in shared libraries, and install the solib event
523 breakpoint. If a "cloned-VM" event was propagated
524 better throughout the core, this wouldn't be
526 solib_create_inferior_hook (0);
532 struct inferior
*parent_inf
;
534 parent_inf
= current_inferior ();
536 /* If we detached from the child, then we have to be careful
537 to not insert breakpoints in the parent until the child
538 is done with the shared memory region. However, if we're
539 staying attached to the child, then we can and should
540 insert breakpoints, so that we can debug it. A
541 subsequent child exec or exit is enough to know when does
542 the child stops using the parent's address space. */
543 parent_inf
->waiting_for_vfork_done
= detach_fork
;
544 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
549 /* Follow the child. */
550 struct inferior
*parent_inf
, *child_inf
;
551 struct program_space
*parent_pspace
;
553 if (print_inferior_events
)
555 std::string parent_pid
= target_pid_to_str (parent_ptid
);
556 std::string child_pid
= target_pid_to_str (child_ptid
);
558 target_terminal::ours_for_output ();
559 fprintf_filtered (gdb_stdlog
,
560 _("[Attaching after %s %s to child %s]\n"),
562 has_vforked
? "vfork" : "fork",
566 /* Add the new inferior first, so that the target_detach below
567 doesn't unpush the target. */
569 child_inf
= add_inferior (child_ptid
.pid ());
571 parent_inf
= current_inferior ();
572 child_inf
->attach_flag
= parent_inf
->attach_flag
;
573 copy_terminal_info (child_inf
, parent_inf
);
574 child_inf
->gdbarch
= parent_inf
->gdbarch
;
575 copy_inferior_target_desc_info (child_inf
, parent_inf
);
577 parent_pspace
= parent_inf
->pspace
;
579 /* If we're vforking, we want to hold on to the parent until the
580 child exits or execs. At child exec or exit time we can
581 remove the old breakpoints from the parent and detach or
582 resume debugging it. Otherwise, detach the parent now; we'll
583 want to reuse it's program/address spaces, but we can't set
584 them to the child before removing breakpoints from the
585 parent, otherwise, the breakpoints module could decide to
586 remove breakpoints from the wrong process (since they'd be
587 assigned to the same address space). */
591 gdb_assert (child_inf
->vfork_parent
== NULL
);
592 gdb_assert (parent_inf
->vfork_child
== NULL
);
593 child_inf
->vfork_parent
= parent_inf
;
594 child_inf
->pending_detach
= 0;
595 parent_inf
->vfork_child
= child_inf
;
596 parent_inf
->pending_detach
= detach_fork
;
597 parent_inf
->waiting_for_vfork_done
= 0;
599 else if (detach_fork
)
601 if (print_inferior_events
)
603 /* Ensure that we have a process ptid. */
604 ptid_t process_ptid
= ptid_t (parent_ptid
.pid ());
606 target_terminal::ours_for_output ();
607 fprintf_filtered (gdb_stdlog
,
608 _("[Detaching after fork from "
610 target_pid_to_str (process_ptid
).c_str ());
613 target_detach (parent_inf
, 0);
616 /* Note that the detach above makes PARENT_INF dangling. */
618 /* Add the child thread to the appropriate lists, and switch to
619 this new thread, before cloning the program space, and
620 informing the solib layer about this new process. */
622 inferior_ptid
= child_ptid
;
623 add_thread_silent (inferior_ptid
);
624 set_current_inferior (child_inf
);
626 /* If this is a vfork child, then the address-space is shared
627 with the parent. If we detached from the parent, then we can
628 reuse the parent's program/address spaces. */
629 if (has_vforked
|| detach_fork
)
631 child_inf
->pspace
= parent_pspace
;
632 child_inf
->aspace
= child_inf
->pspace
->aspace
;
636 child_inf
->aspace
= new_address_space ();
637 child_inf
->pspace
= new program_space (child_inf
->aspace
);
638 child_inf
->removable
= 1;
639 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
640 set_current_program_space (child_inf
->pspace
);
641 clone_program_space (child_inf
->pspace
, parent_pspace
);
643 /* Let the shared library layer (e.g., solib-svr4) learn
644 about this new process, relocate the cloned exec, pull in
645 shared libraries, and install the solib event breakpoint.
646 If a "cloned-VM" event was propagated better throughout
647 the core, this wouldn't be required. */
648 solib_create_inferior_hook (0);
652 return target_follow_fork (follow_child
, detach_fork
);
655 /* Tell the target to follow the fork we're stopped at. Returns true
656 if the inferior should be resumed; false, if the target for some
657 reason decided it's best not to resume. */
662 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
663 int should_resume
= 1;
664 struct thread_info
*tp
;
666 /* Copy user stepping state to the new inferior thread. FIXME: the
667 followed fork child thread should have a copy of most of the
668 parent thread structure's run control related fields, not just these.
669 Initialized to avoid "may be used uninitialized" warnings from gcc. */
670 struct breakpoint
*step_resume_breakpoint
= NULL
;
671 struct breakpoint
*exception_resume_breakpoint
= NULL
;
672 CORE_ADDR step_range_start
= 0;
673 CORE_ADDR step_range_end
= 0;
674 struct frame_id step_frame_id
= { 0 };
675 struct thread_fsm
*thread_fsm
= NULL
;
680 struct target_waitstatus wait_status
;
682 /* Get the last target status returned by target_wait(). */
683 get_last_target_status (&wait_ptid
, &wait_status
);
685 /* If not stopped at a fork event, then there's nothing else to
687 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
688 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
691 /* Check if we switched over from WAIT_PTID, since the event was
693 if (wait_ptid
!= minus_one_ptid
694 && inferior_ptid
!= wait_ptid
)
696 /* We did. Switch back to WAIT_PTID thread, to tell the
697 target to follow it (in either direction). We'll
698 afterwards refuse to resume, and inform the user what
700 thread_info
*wait_thread
701 = find_thread_ptid (wait_ptid
);
702 switch_to_thread (wait_thread
);
707 tp
= inferior_thread ();
709 /* If there were any forks/vforks that were caught and are now to be
710 followed, then do so now. */
711 switch (tp
->pending_follow
.kind
)
713 case TARGET_WAITKIND_FORKED
:
714 case TARGET_WAITKIND_VFORKED
:
716 ptid_t parent
, child
;
718 /* If the user did a next/step, etc, over a fork call,
719 preserve the stepping state in the fork child. */
720 if (follow_child
&& should_resume
)
722 step_resume_breakpoint
= clone_momentary_breakpoint
723 (tp
->control
.step_resume_breakpoint
);
724 step_range_start
= tp
->control
.step_range_start
;
725 step_range_end
= tp
->control
.step_range_end
;
726 step_frame_id
= tp
->control
.step_frame_id
;
727 exception_resume_breakpoint
728 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
729 thread_fsm
= tp
->thread_fsm
;
731 /* For now, delete the parent's sr breakpoint, otherwise,
732 parent/child sr breakpoints are considered duplicates,
733 and the child version will not be installed. Remove
734 this when the breakpoints module becomes aware of
735 inferiors and address spaces. */
736 delete_step_resume_breakpoint (tp
);
737 tp
->control
.step_range_start
= 0;
738 tp
->control
.step_range_end
= 0;
739 tp
->control
.step_frame_id
= null_frame_id
;
740 delete_exception_resume_breakpoint (tp
);
741 tp
->thread_fsm
= NULL
;
744 parent
= inferior_ptid
;
745 child
= tp
->pending_follow
.value
.related_pid
;
747 /* Set up inferior(s) as specified by the caller, and tell the
748 target to do whatever is necessary to follow either parent
750 if (follow_fork_inferior (follow_child
, detach_fork
))
752 /* Target refused to follow, or there's some other reason
753 we shouldn't resume. */
758 /* This pending follow fork event is now handled, one way
759 or another. The previous selected thread may be gone
760 from the lists by now, but if it is still around, need
761 to clear the pending follow request. */
762 tp
= find_thread_ptid (parent
);
764 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
766 /* This makes sure we don't try to apply the "Switched
767 over from WAIT_PID" logic above. */
768 nullify_last_target_wait_ptid ();
770 /* If we followed the child, switch to it... */
773 thread_info
*child_thr
= find_thread_ptid (child
);
774 switch_to_thread (child_thr
);
776 /* ... and preserve the stepping state, in case the
777 user was stepping over the fork call. */
780 tp
= inferior_thread ();
781 tp
->control
.step_resume_breakpoint
782 = step_resume_breakpoint
;
783 tp
->control
.step_range_start
= step_range_start
;
784 tp
->control
.step_range_end
= step_range_end
;
785 tp
->control
.step_frame_id
= step_frame_id
;
786 tp
->control
.exception_resume_breakpoint
787 = exception_resume_breakpoint
;
788 tp
->thread_fsm
= thread_fsm
;
792 /* If we get here, it was because we're trying to
793 resume from a fork catchpoint, but, the user
794 has switched threads away from the thread that
795 forked. In that case, the resume command
796 issued is most likely not applicable to the
797 child, so just warn, and refuse to resume. */
798 warning (_("Not resuming: switched threads "
799 "before following fork child."));
802 /* Reset breakpoints in the child as appropriate. */
803 follow_inferior_reset_breakpoints ();
808 case TARGET_WAITKIND_SPURIOUS
:
809 /* Nothing to follow. */
812 internal_error (__FILE__
, __LINE__
,
813 "Unexpected pending_follow.kind %d\n",
814 tp
->pending_follow
.kind
);
818 return should_resume
;
822 follow_inferior_reset_breakpoints (void)
824 struct thread_info
*tp
= inferior_thread ();
826 /* Was there a step_resume breakpoint? (There was if the user
827 did a "next" at the fork() call.) If so, explicitly reset its
828 thread number. Cloned step_resume breakpoints are disabled on
829 creation, so enable it here now that it is associated with the
832 step_resumes are a form of bp that are made to be per-thread.
833 Since we created the step_resume bp when the parent process
834 was being debugged, and now are switching to the child process,
835 from the breakpoint package's viewpoint, that's a switch of
836 "threads". We must update the bp's notion of which thread
837 it is for, or it'll be ignored when it triggers. */
839 if (tp
->control
.step_resume_breakpoint
)
841 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
842 tp
->control
.step_resume_breakpoint
->loc
->enabled
= 1;
845 /* Treat exception_resume breakpoints like step_resume breakpoints. */
846 if (tp
->control
.exception_resume_breakpoint
)
848 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
849 tp
->control
.exception_resume_breakpoint
->loc
->enabled
= 1;
852 /* Reinsert all breakpoints in the child. The user may have set
853 breakpoints after catching the fork, in which case those
854 were never set in the child, but only in the parent. This makes
855 sure the inserted breakpoints match the breakpoint list. */
857 breakpoint_re_set ();
858 insert_breakpoints ();
861 /* The child has exited or execed: resume threads of the parent the
862 user wanted to be executing. */
865 proceed_after_vfork_done (struct thread_info
*thread
,
868 int pid
= * (int *) arg
;
870 if (thread
->ptid
.pid () == pid
871 && thread
->state
== THREAD_RUNNING
872 && !thread
->executing
873 && !thread
->stop_requested
874 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
877 fprintf_unfiltered (gdb_stdlog
,
878 "infrun: resuming vfork parent thread %s\n",
879 target_pid_to_str (thread
->ptid
).c_str ());
881 switch_to_thread (thread
);
882 clear_proceed_status (0);
883 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
);
889 /* Save/restore inferior_ptid, current program space and current
890 inferior. Only use this if the current context points at an exited
891 inferior (and therefore there's no current thread to save). */
892 class scoped_restore_exited_inferior
895 scoped_restore_exited_inferior ()
896 : m_saved_ptid (&inferior_ptid
)
900 scoped_restore_tmpl
<ptid_t
> m_saved_ptid
;
901 scoped_restore_current_program_space m_pspace
;
902 scoped_restore_current_inferior m_inferior
;
905 /* Called whenever we notice an exec or exit event, to handle
906 detaching or resuming a vfork parent. */
909 handle_vfork_child_exec_or_exit (int exec
)
911 struct inferior
*inf
= current_inferior ();
913 if (inf
->vfork_parent
)
915 int resume_parent
= -1;
917 /* This exec or exit marks the end of the shared memory region
918 between the parent and the child. If the user wanted to
919 detach from the parent, now is the time. */
921 if (inf
->vfork_parent
->pending_detach
)
923 struct thread_info
*tp
;
924 struct program_space
*pspace
;
925 struct address_space
*aspace
;
927 /* follow-fork child, detach-on-fork on. */
929 inf
->vfork_parent
->pending_detach
= 0;
931 gdb::optional
<scoped_restore_exited_inferior
>
932 maybe_restore_inferior
;
933 gdb::optional
<scoped_restore_current_pspace_and_thread
>
934 maybe_restore_thread
;
936 /* If we're handling a child exit, then inferior_ptid points
937 at the inferior's pid, not to a thread. */
939 maybe_restore_inferior
.emplace ();
941 maybe_restore_thread
.emplace ();
943 /* We're letting loose of the parent. */
944 tp
= any_live_thread_of_inferior (inf
->vfork_parent
);
945 switch_to_thread (tp
);
947 /* We're about to detach from the parent, which implicitly
948 removes breakpoints from its address space. There's a
949 catch here: we want to reuse the spaces for the child,
950 but, parent/child are still sharing the pspace at this
951 point, although the exec in reality makes the kernel give
952 the child a fresh set of new pages. The problem here is
953 that the breakpoints module being unaware of this, would
954 likely chose the child process to write to the parent
955 address space. Swapping the child temporarily away from
956 the spaces has the desired effect. Yes, this is "sort
959 pspace
= inf
->pspace
;
960 aspace
= inf
->aspace
;
964 if (print_inferior_events
)
967 = target_pid_to_str (ptid_t (inf
->vfork_parent
->pid
));
969 target_terminal::ours_for_output ();
973 fprintf_filtered (gdb_stdlog
,
974 _("[Detaching vfork parent %s "
975 "after child exec]\n"), pidstr
.c_str ());
979 fprintf_filtered (gdb_stdlog
,
980 _("[Detaching vfork parent %s "
981 "after child exit]\n"), pidstr
.c_str ());
985 target_detach (inf
->vfork_parent
, 0);
988 inf
->pspace
= pspace
;
989 inf
->aspace
= aspace
;
993 /* We're staying attached to the parent, so, really give the
994 child a new address space. */
995 inf
->pspace
= new program_space (maybe_new_address_space ());
996 inf
->aspace
= inf
->pspace
->aspace
;
998 set_current_program_space (inf
->pspace
);
1000 resume_parent
= inf
->vfork_parent
->pid
;
1002 /* Break the bonds. */
1003 inf
->vfork_parent
->vfork_child
= NULL
;
1007 struct program_space
*pspace
;
1009 /* If this is a vfork child exiting, then the pspace and
1010 aspaces were shared with the parent. Since we're
1011 reporting the process exit, we'll be mourning all that is
1012 found in the address space, and switching to null_ptid,
1013 preparing to start a new inferior. But, since we don't
1014 want to clobber the parent's address/program spaces, we
1015 go ahead and create a new one for this exiting
1018 /* Switch to null_ptid while running clone_program_space, so
1019 that clone_program_space doesn't want to read the
1020 selected frame of a dead process. */
1021 scoped_restore restore_ptid
1022 = make_scoped_restore (&inferior_ptid
, null_ptid
);
1024 /* This inferior is dead, so avoid giving the breakpoints
1025 module the option to write through to it (cloning a
1026 program space resets breakpoints). */
1029 pspace
= new program_space (maybe_new_address_space ());
1030 set_current_program_space (pspace
);
1032 inf
->symfile_flags
= SYMFILE_NO_READ
;
1033 clone_program_space (pspace
, inf
->vfork_parent
->pspace
);
1034 inf
->pspace
= pspace
;
1035 inf
->aspace
= pspace
->aspace
;
1037 resume_parent
= inf
->vfork_parent
->pid
;
1038 /* Break the bonds. */
1039 inf
->vfork_parent
->vfork_child
= NULL
;
1042 inf
->vfork_parent
= NULL
;
1044 gdb_assert (current_program_space
== inf
->pspace
);
1046 if (non_stop
&& resume_parent
!= -1)
1048 /* If the user wanted the parent to be running, let it go
1050 scoped_restore_current_thread restore_thread
;
1053 fprintf_unfiltered (gdb_stdlog
,
1054 "infrun: resuming vfork parent process %d\n",
1057 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
1062 /* Enum strings for "set|show follow-exec-mode". */
1064 static const char follow_exec_mode_new
[] = "new";
1065 static const char follow_exec_mode_same
[] = "same";
1066 static const char *const follow_exec_mode_names
[] =
1068 follow_exec_mode_new
,
1069 follow_exec_mode_same
,
1073 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1075 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1076 struct cmd_list_element
*c
, const char *value
)
1078 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1081 /* EXEC_FILE_TARGET is assumed to be non-NULL. */
1084 follow_exec (ptid_t ptid
, char *exec_file_target
)
1086 struct inferior
*inf
= current_inferior ();
1087 int pid
= ptid
.pid ();
1088 ptid_t process_ptid
;
1090 /* This is an exec event that we actually wish to pay attention to.
1091 Refresh our symbol table to the newly exec'd program, remove any
1092 momentary bp's, etc.
1094 If there are breakpoints, they aren't really inserted now,
1095 since the exec() transformed our inferior into a fresh set
1098 We want to preserve symbolic breakpoints on the list, since
1099 we have hopes that they can be reset after the new a.out's
1100 symbol table is read.
1102 However, any "raw" breakpoints must be removed from the list
1103 (e.g., the solib bp's), since their address is probably invalid
1106 And, we DON'T want to call delete_breakpoints() here, since
1107 that may write the bp's "shadow contents" (the instruction
1108 value that was overwritten witha TRAP instruction). Since
1109 we now have a new a.out, those shadow contents aren't valid. */
1111 mark_breakpoints_out ();
1113 /* The target reports the exec event to the main thread, even if
1114 some other thread does the exec, and even if the main thread was
1115 stopped or already gone. We may still have non-leader threads of
1116 the process on our list. E.g., on targets that don't have thread
1117 exit events (like remote); or on native Linux in non-stop mode if
1118 there were only two threads in the inferior and the non-leader
1119 one is the one that execs (and nothing forces an update of the
1120 thread list up to here). When debugging remotely, it's best to
1121 avoid extra traffic, when possible, so avoid syncing the thread
1122 list with the target, and instead go ahead and delete all threads
1123 of the process but one that reported the event. Note this must
1124 be done before calling update_breakpoints_after_exec, as
1125 otherwise clearing the threads' resources would reference stale
1126 thread breakpoints -- it may have been one of these threads that
1127 stepped across the exec. We could just clear their stepping
1128 states, but as long as we're iterating, might as well delete
1129 them. Deleting them now rather than at the next user-visible
1130 stop provides a nicer sequence of events for user and MI
1132 for (thread_info
*th
: all_threads_safe ())
1133 if (th
->ptid
.pid () == pid
&& th
->ptid
!= ptid
)
1136 /* We also need to clear any left over stale state for the
1137 leader/event thread. E.g., if there was any step-resume
1138 breakpoint or similar, it's gone now. We cannot truly
1139 step-to-next statement through an exec(). */
1140 thread_info
*th
= inferior_thread ();
1141 th
->control
.step_resume_breakpoint
= NULL
;
1142 th
->control
.exception_resume_breakpoint
= NULL
;
1143 th
->control
.single_step_breakpoints
= NULL
;
1144 th
->control
.step_range_start
= 0;
1145 th
->control
.step_range_end
= 0;
1147 /* The user may have had the main thread held stopped in the
1148 previous image (e.g., schedlock on, or non-stop). Release
1150 th
->stop_requested
= 0;
1152 update_breakpoints_after_exec ();
1154 /* What is this a.out's name? */
1155 process_ptid
= ptid_t (pid
);
1156 printf_unfiltered (_("%s is executing new program: %s\n"),
1157 target_pid_to_str (process_ptid
).c_str (),
1160 /* We've followed the inferior through an exec. Therefore, the
1161 inferior has essentially been killed & reborn. */
1163 breakpoint_init_inferior (inf_execd
);
1165 gdb::unique_xmalloc_ptr
<char> exec_file_host
1166 = exec_file_find (exec_file_target
, NULL
);
1168 /* If we were unable to map the executable target pathname onto a host
1169 pathname, tell the user that. Otherwise GDB's subsequent behavior
1170 is confusing. Maybe it would even be better to stop at this point
1171 so that the user can specify a file manually before continuing. */
1172 if (exec_file_host
== NULL
)
1173 warning (_("Could not load symbols for executable %s.\n"
1174 "Do you need \"set sysroot\"?"),
1177 /* Reset the shared library package. This ensures that we get a
1178 shlib event when the child reaches "_start", at which point the
1179 dld will have had a chance to initialize the child. */
1180 /* Also, loading a symbol file below may trigger symbol lookups, and
1181 we don't want those to be satisfied by the libraries of the
1182 previous incarnation of this process. */
1183 no_shared_libraries (NULL
, 0);
1185 if (follow_exec_mode_string
== follow_exec_mode_new
)
1187 /* The user wants to keep the old inferior and program spaces
1188 around. Create a new fresh one, and switch to it. */
1190 /* Do exit processing for the original inferior before setting the new
1191 inferior's pid. Having two inferiors with the same pid would confuse
1192 find_inferior_p(t)id. Transfer the terminal state and info from the
1193 old to the new inferior. */
1194 inf
= add_inferior_with_spaces ();
1195 swap_terminal_info (inf
, current_inferior ());
1196 exit_inferior_silent (current_inferior ());
1199 target_follow_exec (inf
, exec_file_target
);
1201 set_current_inferior (inf
);
1202 set_current_program_space (inf
->pspace
);
1207 /* The old description may no longer be fit for the new image.
1208 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1209 old description; we'll read a new one below. No need to do
1210 this on "follow-exec-mode new", as the old inferior stays
1211 around (its description is later cleared/refetched on
1213 target_clear_description ();
1216 gdb_assert (current_program_space
== inf
->pspace
);
1218 /* Attempt to open the exec file. SYMFILE_DEFER_BP_RESET is used
1219 because the proper displacement for a PIE (Position Independent
1220 Executable) main symbol file will only be computed by
1221 solib_create_inferior_hook below. breakpoint_re_set would fail
1222 to insert the breakpoints with the zero displacement. */
1223 try_open_exec_file (exec_file_host
.get (), inf
, SYMFILE_DEFER_BP_RESET
);
1225 /* If the target can specify a description, read it. Must do this
1226 after flipping to the new executable (because the target supplied
1227 description must be compatible with the executable's
1228 architecture, and the old executable may e.g., be 32-bit, while
1229 the new one 64-bit), and before anything involving memory or
1231 target_find_description ();
1233 solib_create_inferior_hook (0);
1235 jit_inferior_created_hook ();
1237 breakpoint_re_set ();
1239 /* Reinsert all breakpoints. (Those which were symbolic have
1240 been reset to the proper address in the new a.out, thanks
1241 to symbol_file_command...). */
1242 insert_breakpoints ();
1244 /* The next resume of this inferior should bring it to the shlib
1245 startup breakpoints. (If the user had also set bp's on
1246 "main" from the old (parent) process, then they'll auto-
1247 matically get reset there in the new process.). */
1250 /* The queue of threads that need to do a step-over operation to get
1251 past e.g., a breakpoint. What technique is used to step over the
1252 breakpoint/watchpoint does not matter -- all threads end up in the
1253 same queue, to maintain rough temporal order of execution, in order
1254 to avoid starvation, otherwise, we could e.g., find ourselves
1255 constantly stepping the same couple threads past their breakpoints
1256 over and over, if the single-step finish fast enough. */
1257 struct thread_info
*step_over_queue_head
;
1259 /* Bit flags indicating what the thread needs to step over. */
1261 enum step_over_what_flag
1263 /* Step over a breakpoint. */
1264 STEP_OVER_BREAKPOINT
= 1,
1266 /* Step past a non-continuable watchpoint, in order to let the
1267 instruction execute so we can evaluate the watchpoint
1269 STEP_OVER_WATCHPOINT
= 2
1271 DEF_ENUM_FLAGS_TYPE (enum step_over_what_flag
, step_over_what
);
1273 /* Info about an instruction that is being stepped over. */
1275 struct step_over_info
1277 /* If we're stepping past a breakpoint, this is the address space
1278 and address of the instruction the breakpoint is set at. We'll
1279 skip inserting all breakpoints here. Valid iff ASPACE is
1281 const address_space
*aspace
;
1284 /* The instruction being stepped over triggers a nonsteppable
1285 watchpoint. If true, we'll skip inserting watchpoints. */
1286 int nonsteppable_watchpoint_p
;
1288 /* The thread's global number. */
1292 /* The step-over info of the location that is being stepped over.
1294 Note that with async/breakpoint always-inserted mode, a user might
1295 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1296 being stepped over. As setting a new breakpoint inserts all
1297 breakpoints, we need to make sure the breakpoint being stepped over
1298 isn't inserted then. We do that by only clearing the step-over
1299 info when the step-over is actually finished (or aborted).
1301 Presently GDB can only step over one breakpoint at any given time.
1302 Given threads that can't run code in the same address space as the
1303 breakpoint's can't really miss the breakpoint, GDB could be taught
1304 to step-over at most one breakpoint per address space (so this info
1305 could move to the address space object if/when GDB is extended).
1306 The set of breakpoints being stepped over will normally be much
1307 smaller than the set of all breakpoints, so a flag in the
1308 breakpoint location structure would be wasteful. A separate list
1309 also saves complexity and run-time, as otherwise we'd have to go
1310 through all breakpoint locations clearing their flag whenever we
1311 start a new sequence. Similar considerations weigh against storing
1312 this info in the thread object. Plus, not all step overs actually
1313 have breakpoint locations -- e.g., stepping past a single-step
1314 breakpoint, or stepping to complete a non-continuable
1316 static struct step_over_info step_over_info
;
1318 /* Record the address of the breakpoint/instruction we're currently
1320 N.B. We record the aspace and address now, instead of say just the thread,
1321 because when we need the info later the thread may be running. */
1324 set_step_over_info (const address_space
*aspace
, CORE_ADDR address
,
1325 int nonsteppable_watchpoint_p
,
1328 step_over_info
.aspace
= aspace
;
1329 step_over_info
.address
= address
;
1330 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1331 step_over_info
.thread
= thread
;
1334 /* Called when we're not longer stepping over a breakpoint / an
1335 instruction, so all breakpoints are free to be (re)inserted. */
1338 clear_step_over_info (void)
1341 fprintf_unfiltered (gdb_stdlog
,
1342 "infrun: clear_step_over_info\n");
1343 step_over_info
.aspace
= NULL
;
1344 step_over_info
.address
= 0;
1345 step_over_info
.nonsteppable_watchpoint_p
= 0;
1346 step_over_info
.thread
= -1;
1352 stepping_past_instruction_at (struct address_space
*aspace
,
1355 return (step_over_info
.aspace
!= NULL
1356 && breakpoint_address_match (aspace
, address
,
1357 step_over_info
.aspace
,
1358 step_over_info
.address
));
1364 thread_is_stepping_over_breakpoint (int thread
)
1366 return (step_over_info
.thread
!= -1
1367 && thread
== step_over_info
.thread
);
1373 stepping_past_nonsteppable_watchpoint (void)
1375 return step_over_info
.nonsteppable_watchpoint_p
;
1378 /* Returns true if step-over info is valid. */
1381 step_over_info_valid_p (void)
1383 return (step_over_info
.aspace
!= NULL
1384 || stepping_past_nonsteppable_watchpoint ());
1388 /* Displaced stepping. */
1390 /* In non-stop debugging mode, we must take special care to manage
1391 breakpoints properly; in particular, the traditional strategy for
1392 stepping a thread past a breakpoint it has hit is unsuitable.
1393 'Displaced stepping' is a tactic for stepping one thread past a
1394 breakpoint it has hit while ensuring that other threads running
1395 concurrently will hit the breakpoint as they should.
1397 The traditional way to step a thread T off a breakpoint in a
1398 multi-threaded program in all-stop mode is as follows:
1400 a0) Initially, all threads are stopped, and breakpoints are not
1402 a1) We single-step T, leaving breakpoints uninserted.
1403 a2) We insert breakpoints, and resume all threads.
1405 In non-stop debugging, however, this strategy is unsuitable: we
1406 don't want to have to stop all threads in the system in order to
1407 continue or step T past a breakpoint. Instead, we use displaced
1410 n0) Initially, T is stopped, other threads are running, and
1411 breakpoints are inserted.
1412 n1) We copy the instruction "under" the breakpoint to a separate
1413 location, outside the main code stream, making any adjustments
1414 to the instruction, register, and memory state as directed by
1416 n2) We single-step T over the instruction at its new location.
1417 n3) We adjust the resulting register and memory state as directed
1418 by T's architecture. This includes resetting T's PC to point
1419 back into the main instruction stream.
1422 This approach depends on the following gdbarch methods:
1424 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1425 indicate where to copy the instruction, and how much space must
1426 be reserved there. We use these in step n1.
1428 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1429 address, and makes any necessary adjustments to the instruction,
1430 register contents, and memory. We use this in step n1.
1432 - gdbarch_displaced_step_fixup adjusts registers and memory after
1433 we have successfuly single-stepped the instruction, to yield the
1434 same effect the instruction would have had if we had executed it
1435 at its original address. We use this in step n3.
1437 The gdbarch_displaced_step_copy_insn and
1438 gdbarch_displaced_step_fixup functions must be written so that
1439 copying an instruction with gdbarch_displaced_step_copy_insn,
1440 single-stepping across the copied instruction, and then applying
1441 gdbarch_displaced_insn_fixup should have the same effects on the
1442 thread's memory and registers as stepping the instruction in place
1443 would have. Exactly which responsibilities fall to the copy and
1444 which fall to the fixup is up to the author of those functions.
1446 See the comments in gdbarch.sh for details.
1448 Note that displaced stepping and software single-step cannot
1449 currently be used in combination, although with some care I think
1450 they could be made to. Software single-step works by placing
1451 breakpoints on all possible subsequent instructions; if the
1452 displaced instruction is a PC-relative jump, those breakpoints
1453 could fall in very strange places --- on pages that aren't
1454 executable, or at addresses that are not proper instruction
1455 boundaries. (We do generally let other threads run while we wait
1456 to hit the software single-step breakpoint, and they might
1457 encounter such a corrupted instruction.) One way to work around
1458 this would be to have gdbarch_displaced_step_copy_insn fully
1459 simulate the effect of PC-relative instructions (and return NULL)
1460 on architectures that use software single-stepping.
1462 In non-stop mode, we can have independent and simultaneous step
1463 requests, so more than one thread may need to simultaneously step
1464 over a breakpoint. The current implementation assumes there is
1465 only one scratch space per process. In this case, we have to
1466 serialize access to the scratch space. If thread A wants to step
1467 over a breakpoint, but we are currently waiting for some other
1468 thread to complete a displaced step, we leave thread A stopped and
1469 place it in the displaced_step_request_queue. Whenever a displaced
1470 step finishes, we pick the next thread in the queue and start a new
1471 displaced step operation on it. See displaced_step_prepare and
1472 displaced_step_fixup for details. */
1474 /* Default destructor for displaced_step_closure. */
1476 displaced_step_closure::~displaced_step_closure () = default;
1478 /* Get the displaced stepping state of process PID. */
1480 static displaced_step_inferior_state
*
1481 get_displaced_stepping_state (inferior
*inf
)
1483 return &inf
->displaced_step_state
;
1486 /* Returns true if any inferior has a thread doing a displaced
1490 displaced_step_in_progress_any_inferior ()
1492 for (inferior
*i
: all_inferiors ())
1494 if (i
->displaced_step_state
.step_thread
!= nullptr)
1501 /* Return true if thread represented by PTID is doing a displaced
1505 displaced_step_in_progress_thread (thread_info
*thread
)
1507 gdb_assert (thread
!= NULL
);
1509 return get_displaced_stepping_state (thread
->inf
)->step_thread
== thread
;
1512 /* Return true if process PID has a thread doing a displaced step. */
1515 displaced_step_in_progress (inferior
*inf
)
1517 return get_displaced_stepping_state (inf
)->step_thread
!= nullptr;
1520 /* If inferior is in displaced stepping, and ADDR equals to starting address
1521 of copy area, return corresponding displaced_step_closure. Otherwise,
1524 struct displaced_step_closure
*
1525 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1527 displaced_step_inferior_state
*displaced
1528 = get_displaced_stepping_state (current_inferior ());
1530 /* If checking the mode of displaced instruction in copy area. */
1531 if (displaced
->step_thread
!= nullptr
1532 && displaced
->step_copy
== addr
)
1533 return displaced
->step_closure
;
1539 infrun_inferior_exit (struct inferior
*inf
)
1541 inf
->displaced_step_state
.reset ();
1544 /* If ON, and the architecture supports it, GDB will use displaced
1545 stepping to step over breakpoints. If OFF, or if the architecture
1546 doesn't support it, GDB will instead use the traditional
1547 hold-and-step approach. If AUTO (which is the default), GDB will
1548 decide which technique to use to step over breakpoints depending on
1549 which of all-stop or non-stop mode is active --- displaced stepping
1550 in non-stop mode; hold-and-step in all-stop mode. */
1552 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1555 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1556 struct cmd_list_element
*c
,
1559 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1560 fprintf_filtered (file
,
1561 _("Debugger's willingness to use displaced stepping "
1562 "to step over breakpoints is %s (currently %s).\n"),
1563 value
, target_is_non_stop_p () ? "on" : "off");
1565 fprintf_filtered (file
,
1566 _("Debugger's willingness to use displaced stepping "
1567 "to step over breakpoints is %s.\n"), value
);
1570 /* Return non-zero if displaced stepping can/should be used to step
1571 over breakpoints of thread TP. */
1574 use_displaced_stepping (struct thread_info
*tp
)
1576 struct regcache
*regcache
= get_thread_regcache (tp
);
1577 struct gdbarch
*gdbarch
= regcache
->arch ();
1578 displaced_step_inferior_state
*displaced_state
1579 = get_displaced_stepping_state (tp
->inf
);
1581 return (((can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
1582 && target_is_non_stop_p ())
1583 || can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1584 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1585 && find_record_target () == NULL
1586 && !displaced_state
->failed_before
);
1589 /* Clean out any stray displaced stepping state. */
1591 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1593 /* Indicate that there is no cleanup pending. */
1594 displaced
->step_thread
= nullptr;
1596 delete displaced
->step_closure
;
1597 displaced
->step_closure
= NULL
;
1600 /* A cleanup that wraps displaced_step_clear. */
1601 using displaced_step_clear_cleanup
1602 = FORWARD_SCOPE_EXIT (displaced_step_clear
);
1604 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1606 displaced_step_dump_bytes (struct ui_file
*file
,
1607 const gdb_byte
*buf
,
1612 for (i
= 0; i
< len
; i
++)
1613 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1614 fputs_unfiltered ("\n", file
);
1617 /* Prepare to single-step, using displaced stepping.
1619 Note that we cannot use displaced stepping when we have a signal to
1620 deliver. If we have a signal to deliver and an instruction to step
1621 over, then after the step, there will be no indication from the
1622 target whether the thread entered a signal handler or ignored the
1623 signal and stepped over the instruction successfully --- both cases
1624 result in a simple SIGTRAP. In the first case we mustn't do a
1625 fixup, and in the second case we must --- but we can't tell which.
1626 Comments in the code for 'random signals' in handle_inferior_event
1627 explain how we handle this case instead.
1629 Returns 1 if preparing was successful -- this thread is going to be
1630 stepped now; 0 if displaced stepping this thread got queued; or -1
1631 if this instruction can't be displaced stepped. */
1634 displaced_step_prepare_throw (thread_info
*tp
)
1636 regcache
*regcache
= get_thread_regcache (tp
);
1637 struct gdbarch
*gdbarch
= regcache
->arch ();
1638 const address_space
*aspace
= regcache
->aspace ();
1639 CORE_ADDR original
, copy
;
1641 struct displaced_step_closure
*closure
;
1644 /* We should never reach this function if the architecture does not
1645 support displaced stepping. */
1646 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1648 /* Nor if the thread isn't meant to step over a breakpoint. */
1649 gdb_assert (tp
->control
.trap_expected
);
1651 /* Disable range stepping while executing in the scratch pad. We
1652 want a single-step even if executing the displaced instruction in
1653 the scratch buffer lands within the stepping range (e.g., a
1655 tp
->control
.may_range_step
= 0;
1657 /* We have to displaced step one thread at a time, as we only have
1658 access to a single scratch space per inferior. */
1660 displaced_step_inferior_state
*displaced
1661 = get_displaced_stepping_state (tp
->inf
);
1663 if (displaced
->step_thread
!= nullptr)
1665 /* Already waiting for a displaced step to finish. Defer this
1666 request and place in queue. */
1668 if (debug_displaced
)
1669 fprintf_unfiltered (gdb_stdlog
,
1670 "displaced: deferring step of %s\n",
1671 target_pid_to_str (tp
->ptid
).c_str ());
1673 thread_step_over_chain_enqueue (tp
);
1678 if (debug_displaced
)
1679 fprintf_unfiltered (gdb_stdlog
,
1680 "displaced: stepping %s now\n",
1681 target_pid_to_str (tp
->ptid
).c_str ());
1684 displaced_step_clear (displaced
);
1686 scoped_restore_current_thread restore_thread
;
1688 switch_to_thread (tp
);
1690 original
= regcache_read_pc (regcache
);
1692 copy
= gdbarch_displaced_step_location (gdbarch
);
1693 len
= gdbarch_max_insn_length (gdbarch
);
1695 if (breakpoint_in_range_p (aspace
, copy
, len
))
1697 /* There's a breakpoint set in the scratch pad location range
1698 (which is usually around the entry point). We'd either
1699 install it before resuming, which would overwrite/corrupt the
1700 scratch pad, or if it was already inserted, this displaced
1701 step would overwrite it. The latter is OK in the sense that
1702 we already assume that no thread is going to execute the code
1703 in the scratch pad range (after initial startup) anyway, but
1704 the former is unacceptable. Simply punt and fallback to
1705 stepping over this breakpoint in-line. */
1706 if (debug_displaced
)
1708 fprintf_unfiltered (gdb_stdlog
,
1709 "displaced: breakpoint set in scratch pad. "
1710 "Stepping over breakpoint in-line instead.\n");
1716 /* Save the original contents of the copy area. */
1717 displaced
->step_saved_copy
.resize (len
);
1718 status
= target_read_memory (copy
, displaced
->step_saved_copy
.data (), len
);
1720 throw_error (MEMORY_ERROR
,
1721 _("Error accessing memory address %s (%s) for "
1722 "displaced-stepping scratch space."),
1723 paddress (gdbarch
, copy
), safe_strerror (status
));
1724 if (debug_displaced
)
1726 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1727 paddress (gdbarch
, copy
));
1728 displaced_step_dump_bytes (gdb_stdlog
,
1729 displaced
->step_saved_copy
.data (),
1733 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1734 original
, copy
, regcache
);
1735 if (closure
== NULL
)
1737 /* The architecture doesn't know how or want to displaced step
1738 this instruction or instruction sequence. Fallback to
1739 stepping over the breakpoint in-line. */
1743 /* Save the information we need to fix things up if the step
1745 displaced
->step_thread
= tp
;
1746 displaced
->step_gdbarch
= gdbarch
;
1747 displaced
->step_closure
= closure
;
1748 displaced
->step_original
= original
;
1749 displaced
->step_copy
= copy
;
1752 displaced_step_clear_cleanup
cleanup (displaced
);
1754 /* Resume execution at the copy. */
1755 regcache_write_pc (regcache
, copy
);
1760 if (debug_displaced
)
1761 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1762 paddress (gdbarch
, copy
));
1767 /* Wrapper for displaced_step_prepare_throw that disabled further
1768 attempts at displaced stepping if we get a memory error. */
1771 displaced_step_prepare (thread_info
*thread
)
1777 prepared
= displaced_step_prepare_throw (thread
);
1779 CATCH (ex
, RETURN_MASK_ERROR
)
1781 struct displaced_step_inferior_state
*displaced_state
;
1783 if (ex
.error
!= MEMORY_ERROR
1784 && ex
.error
!= NOT_SUPPORTED_ERROR
)
1785 throw_exception (ex
);
1789 fprintf_unfiltered (gdb_stdlog
,
1790 "infrun: disabling displaced stepping: %s\n",
1794 /* Be verbose if "set displaced-stepping" is "on", silent if
1796 if (can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1798 warning (_("disabling displaced stepping: %s"),
1802 /* Disable further displaced stepping attempts. */
1804 = get_displaced_stepping_state (thread
->inf
);
1805 displaced_state
->failed_before
= 1;
1813 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1814 const gdb_byte
*myaddr
, int len
)
1816 scoped_restore save_inferior_ptid
= make_scoped_restore (&inferior_ptid
);
1818 inferior_ptid
= ptid
;
1819 write_memory (memaddr
, myaddr
, len
);
1822 /* Restore the contents of the copy area for thread PTID. */
1825 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1828 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1830 write_memory_ptid (ptid
, displaced
->step_copy
,
1831 displaced
->step_saved_copy
.data (), len
);
1832 if (debug_displaced
)
1833 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1834 target_pid_to_str (ptid
).c_str (),
1835 paddress (displaced
->step_gdbarch
,
1836 displaced
->step_copy
));
1839 /* If we displaced stepped an instruction successfully, adjust
1840 registers and memory to yield the same effect the instruction would
1841 have had if we had executed it at its original address, and return
1842 1. If the instruction didn't complete, relocate the PC and return
1843 -1. If the thread wasn't displaced stepping, return 0. */
1846 displaced_step_fixup (thread_info
*event_thread
, enum gdb_signal signal
)
1848 struct displaced_step_inferior_state
*displaced
1849 = get_displaced_stepping_state (event_thread
->inf
);
1852 /* Was this event for the thread we displaced? */
1853 if (displaced
->step_thread
!= event_thread
)
1856 displaced_step_clear_cleanup
cleanup (displaced
);
1858 displaced_step_restore (displaced
, displaced
->step_thread
->ptid
);
1860 /* Fixup may need to read memory/registers. Switch to the thread
1861 that we're fixing up. Also, target_stopped_by_watchpoint checks
1862 the current thread. */
1863 switch_to_thread (event_thread
);
1865 /* Did the instruction complete successfully? */
1866 if (signal
== GDB_SIGNAL_TRAP
1867 && !(target_stopped_by_watchpoint ()
1868 && (gdbarch_have_nonsteppable_watchpoint (displaced
->step_gdbarch
)
1869 || target_have_steppable_watchpoint
)))
1871 /* Fix up the resulting state. */
1872 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
1873 displaced
->step_closure
,
1874 displaced
->step_original
,
1875 displaced
->step_copy
,
1876 get_thread_regcache (displaced
->step_thread
));
1881 /* Since the instruction didn't complete, all we can do is
1883 struct regcache
*regcache
= get_thread_regcache (event_thread
);
1884 CORE_ADDR pc
= regcache_read_pc (regcache
);
1886 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
1887 regcache_write_pc (regcache
, pc
);
1894 /* Data to be passed around while handling an event. This data is
1895 discarded between events. */
1896 struct execution_control_state
1899 /* The thread that got the event, if this was a thread event; NULL
1901 struct thread_info
*event_thread
;
1903 struct target_waitstatus ws
;
1904 int stop_func_filled_in
;
1905 CORE_ADDR stop_func_start
;
1906 CORE_ADDR stop_func_end
;
1907 const char *stop_func_name
;
1910 /* True if the event thread hit the single-step breakpoint of
1911 another thread. Thus the event doesn't cause a stop, the thread
1912 needs to be single-stepped past the single-step breakpoint before
1913 we can switch back to the original stepping thread. */
1914 int hit_singlestep_breakpoint
;
1917 /* Clear ECS and set it to point at TP. */
1920 reset_ecs (struct execution_control_state
*ecs
, struct thread_info
*tp
)
1922 memset (ecs
, 0, sizeof (*ecs
));
1923 ecs
->event_thread
= tp
;
1924 ecs
->ptid
= tp
->ptid
;
1927 static void keep_going_pass_signal (struct execution_control_state
*ecs
);
1928 static void prepare_to_wait (struct execution_control_state
*ecs
);
1929 static int keep_going_stepped_thread (struct thread_info
*tp
);
1930 static step_over_what
thread_still_needs_step_over (struct thread_info
*tp
);
1932 /* Are there any pending step-over requests? If so, run all we can
1933 now and return true. Otherwise, return false. */
1936 start_step_over (void)
1938 struct thread_info
*tp
, *next
;
1940 /* Don't start a new step-over if we already have an in-line
1941 step-over operation ongoing. */
1942 if (step_over_info_valid_p ())
1945 for (tp
= step_over_queue_head
; tp
!= NULL
; tp
= next
)
1947 struct execution_control_state ecss
;
1948 struct execution_control_state
*ecs
= &ecss
;
1949 step_over_what step_what
;
1950 int must_be_in_line
;
1952 gdb_assert (!tp
->stop_requested
);
1954 next
= thread_step_over_chain_next (tp
);
1956 /* If this inferior already has a displaced step in process,
1957 don't start a new one. */
1958 if (displaced_step_in_progress (tp
->inf
))
1961 step_what
= thread_still_needs_step_over (tp
);
1962 must_be_in_line
= ((step_what
& STEP_OVER_WATCHPOINT
)
1963 || ((step_what
& STEP_OVER_BREAKPOINT
)
1964 && !use_displaced_stepping (tp
)));
1966 /* We currently stop all threads of all processes to step-over
1967 in-line. If we need to start a new in-line step-over, let
1968 any pending displaced steps finish first. */
1969 if (must_be_in_line
&& displaced_step_in_progress_any_inferior ())
1972 thread_step_over_chain_remove (tp
);
1974 if (step_over_queue_head
== NULL
)
1977 fprintf_unfiltered (gdb_stdlog
,
1978 "infrun: step-over queue now empty\n");
1981 if (tp
->control
.trap_expected
1985 internal_error (__FILE__
, __LINE__
,
1986 "[%s] has inconsistent state: "
1987 "trap_expected=%d, resumed=%d, executing=%d\n",
1988 target_pid_to_str (tp
->ptid
).c_str (),
1989 tp
->control
.trap_expected
,
1995 fprintf_unfiltered (gdb_stdlog
,
1996 "infrun: resuming [%s] for step-over\n",
1997 target_pid_to_str (tp
->ptid
).c_str ());
1999 /* keep_going_pass_signal skips the step-over if the breakpoint
2000 is no longer inserted. In all-stop, we want to keep looking
2001 for a thread that needs a step-over instead of resuming TP,
2002 because we wouldn't be able to resume anything else until the
2003 target stops again. In non-stop, the resume always resumes
2004 only TP, so it's OK to let the thread resume freely. */
2005 if (!target_is_non_stop_p () && !step_what
)
2008 switch_to_thread (tp
);
2009 reset_ecs (ecs
, tp
);
2010 keep_going_pass_signal (ecs
);
2012 if (!ecs
->wait_some_more
)
2013 error (_("Command aborted."));
2015 gdb_assert (tp
->resumed
);
2017 /* If we started a new in-line step-over, we're done. */
2018 if (step_over_info_valid_p ())
2020 gdb_assert (tp
->control
.trap_expected
);
2024 if (!target_is_non_stop_p ())
2026 /* On all-stop, shouldn't have resumed unless we needed a
2028 gdb_assert (tp
->control
.trap_expected
2029 || tp
->step_after_step_resume_breakpoint
);
2031 /* With remote targets (at least), in all-stop, we can't
2032 issue any further remote commands until the program stops
2037 /* Either the thread no longer needed a step-over, or a new
2038 displaced stepping sequence started. Even in the latter
2039 case, continue looking. Maybe we can also start another
2040 displaced step on a thread of other process. */
2046 /* Update global variables holding ptids to hold NEW_PTID if they were
2047 holding OLD_PTID. */
2049 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
2051 if (inferior_ptid
== old_ptid
)
2052 inferior_ptid
= new_ptid
;
2057 static const char schedlock_off
[] = "off";
2058 static const char schedlock_on
[] = "on";
2059 static const char schedlock_step
[] = "step";
2060 static const char schedlock_replay
[] = "replay";
2061 static const char *const scheduler_enums
[] = {
2068 static const char *scheduler_mode
= schedlock_replay
;
2070 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
2071 struct cmd_list_element
*c
, const char *value
)
2073 fprintf_filtered (file
,
2074 _("Mode for locking scheduler "
2075 "during execution is \"%s\".\n"),
2080 set_schedlock_func (const char *args
, int from_tty
, struct cmd_list_element
*c
)
2082 if (!target_can_lock_scheduler
)
2084 scheduler_mode
= schedlock_off
;
2085 error (_("Target '%s' cannot support this command."), target_shortname
);
2089 /* True if execution commands resume all threads of all processes by
2090 default; otherwise, resume only threads of the current inferior
2092 int sched_multi
= 0;
2094 /* Try to setup for software single stepping over the specified location.
2095 Return 1 if target_resume() should use hardware single step.
2097 GDBARCH the current gdbarch.
2098 PC the location to step over. */
2101 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
2105 if (execution_direction
== EXEC_FORWARD
2106 && gdbarch_software_single_step_p (gdbarch
))
2107 hw_step
= !insert_single_step_breakpoints (gdbarch
);
2115 user_visible_resume_ptid (int step
)
2121 /* With non-stop mode on, threads are always handled
2123 resume_ptid
= inferior_ptid
;
2125 else if ((scheduler_mode
== schedlock_on
)
2126 || (scheduler_mode
== schedlock_step
&& step
))
2128 /* User-settable 'scheduler' mode requires solo thread
2130 resume_ptid
= inferior_ptid
;
2132 else if ((scheduler_mode
== schedlock_replay
)
2133 && target_record_will_replay (minus_one_ptid
, execution_direction
))
2135 /* User-settable 'scheduler' mode requires solo thread resume in replay
2137 resume_ptid
= inferior_ptid
;
2139 else if (!sched_multi
&& target_supports_multi_process ())
2141 /* Resume all threads of the current process (and none of other
2143 resume_ptid
= ptid_t (inferior_ptid
.pid ());
2147 /* Resume all threads of all processes. */
2148 resume_ptid
= RESUME_ALL
;
2154 /* Return a ptid representing the set of threads that we will resume,
2155 in the perspective of the target, assuming run control handling
2156 does not require leaving some threads stopped (e.g., stepping past
2157 breakpoint). USER_STEP indicates whether we're about to start the
2158 target for a stepping command. */
2161 internal_resume_ptid (int user_step
)
2163 /* In non-stop, we always control threads individually. Note that
2164 the target may always work in non-stop mode even with "set
2165 non-stop off", in which case user_visible_resume_ptid could
2166 return a wildcard ptid. */
2167 if (target_is_non_stop_p ())
2168 return inferior_ptid
;
2170 return user_visible_resume_ptid (user_step
);
2173 /* Wrapper for target_resume, that handles infrun-specific
2177 do_target_resume (ptid_t resume_ptid
, int step
, enum gdb_signal sig
)
2179 struct thread_info
*tp
= inferior_thread ();
2181 gdb_assert (!tp
->stop_requested
);
2183 /* Install inferior's terminal modes. */
2184 target_terminal::inferior ();
2186 /* Avoid confusing the next resume, if the next stop/resume
2187 happens to apply to another thread. */
2188 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2190 /* Advise target which signals may be handled silently.
2192 If we have removed breakpoints because we are stepping over one
2193 in-line (in any thread), we need to receive all signals to avoid
2194 accidentally skipping a breakpoint during execution of a signal
2197 Likewise if we're displaced stepping, otherwise a trap for a
2198 breakpoint in a signal handler might be confused with the
2199 displaced step finishing. We don't make the displaced_step_fixup
2200 step distinguish the cases instead, because:
2202 - a backtrace while stopped in the signal handler would show the
2203 scratch pad as frame older than the signal handler, instead of
2204 the real mainline code.
2206 - when the thread is later resumed, the signal handler would
2207 return to the scratch pad area, which would no longer be
2209 if (step_over_info_valid_p ()
2210 || displaced_step_in_progress (tp
->inf
))
2211 target_pass_signals ({});
2213 target_pass_signals (signal_pass
);
2215 target_resume (resume_ptid
, step
, sig
);
2217 target_commit_resume ();
2220 /* Resume the inferior. SIG is the signal to give the inferior
2221 (GDB_SIGNAL_0 for none). Note: don't call this directly; instead
2222 call 'resume', which handles exceptions. */
2225 resume_1 (enum gdb_signal sig
)
2227 struct regcache
*regcache
= get_current_regcache ();
2228 struct gdbarch
*gdbarch
= regcache
->arch ();
2229 struct thread_info
*tp
= inferior_thread ();
2230 CORE_ADDR pc
= regcache_read_pc (regcache
);
2231 const address_space
*aspace
= regcache
->aspace ();
2233 /* This represents the user's step vs continue request. When
2234 deciding whether "set scheduler-locking step" applies, it's the
2235 user's intention that counts. */
2236 const int user_step
= tp
->control
.stepping_command
;
2237 /* This represents what we'll actually request the target to do.
2238 This can decay from a step to a continue, if e.g., we need to
2239 implement single-stepping with breakpoints (software
2243 gdb_assert (!tp
->stop_requested
);
2244 gdb_assert (!thread_is_in_step_over_chain (tp
));
2246 if (tp
->suspend
.waitstatus_pending_p
)
2251 = target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2253 fprintf_unfiltered (gdb_stdlog
,
2254 "infrun: resume: thread %s has pending wait "
2255 "status %s (currently_stepping=%d).\n",
2256 target_pid_to_str (tp
->ptid
).c_str (),
2258 currently_stepping (tp
));
2263 /* FIXME: What should we do if we are supposed to resume this
2264 thread with a signal? Maybe we should maintain a queue of
2265 pending signals to deliver. */
2266 if (sig
!= GDB_SIGNAL_0
)
2268 warning (_("Couldn't deliver signal %s to %s."),
2269 gdb_signal_to_name (sig
),
2270 target_pid_to_str (tp
->ptid
).c_str ());
2273 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2275 if (target_can_async_p ())
2278 /* Tell the event loop we have an event to process. */
2279 mark_async_event_handler (infrun_async_inferior_event_token
);
2284 tp
->stepped_breakpoint
= 0;
2286 /* Depends on stepped_breakpoint. */
2287 step
= currently_stepping (tp
);
2289 if (current_inferior ()->waiting_for_vfork_done
)
2291 /* Don't try to single-step a vfork parent that is waiting for
2292 the child to get out of the shared memory region (by exec'ing
2293 or exiting). This is particularly important on software
2294 single-step archs, as the child process would trip on the
2295 software single step breakpoint inserted for the parent
2296 process. Since the parent will not actually execute any
2297 instruction until the child is out of the shared region (such
2298 are vfork's semantics), it is safe to simply continue it.
2299 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2300 the parent, and tell it to `keep_going', which automatically
2301 re-sets it stepping. */
2303 fprintf_unfiltered (gdb_stdlog
,
2304 "infrun: resume : clear step\n");
2309 fprintf_unfiltered (gdb_stdlog
,
2310 "infrun: resume (step=%d, signal=%s), "
2311 "trap_expected=%d, current thread [%s] at %s\n",
2312 step
, gdb_signal_to_symbol_string (sig
),
2313 tp
->control
.trap_expected
,
2314 target_pid_to_str (inferior_ptid
).c_str (),
2315 paddress (gdbarch
, pc
));
2317 /* Normally, by the time we reach `resume', the breakpoints are either
2318 removed or inserted, as appropriate. The exception is if we're sitting
2319 at a permanent breakpoint; we need to step over it, but permanent
2320 breakpoints can't be removed. So we have to test for it here. */
2321 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2323 if (sig
!= GDB_SIGNAL_0
)
2325 /* We have a signal to pass to the inferior. The resume
2326 may, or may not take us to the signal handler. If this
2327 is a step, we'll need to stop in the signal handler, if
2328 there's one, (if the target supports stepping into
2329 handlers), or in the next mainline instruction, if
2330 there's no handler. If this is a continue, we need to be
2331 sure to run the handler with all breakpoints inserted.
2332 In all cases, set a breakpoint at the current address
2333 (where the handler returns to), and once that breakpoint
2334 is hit, resume skipping the permanent breakpoint. If
2335 that breakpoint isn't hit, then we've stepped into the
2336 signal handler (or hit some other event). We'll delete
2337 the step-resume breakpoint then. */
2340 fprintf_unfiltered (gdb_stdlog
,
2341 "infrun: resume: skipping permanent breakpoint, "
2342 "deliver signal first\n");
2344 clear_step_over_info ();
2345 tp
->control
.trap_expected
= 0;
2347 if (tp
->control
.step_resume_breakpoint
== NULL
)
2349 /* Set a "high-priority" step-resume, as we don't want
2350 user breakpoints at PC to trigger (again) when this
2352 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2353 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2355 tp
->step_after_step_resume_breakpoint
= step
;
2358 insert_breakpoints ();
2362 /* There's no signal to pass, we can go ahead and skip the
2363 permanent breakpoint manually. */
2365 fprintf_unfiltered (gdb_stdlog
,
2366 "infrun: resume: skipping permanent breakpoint\n");
2367 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2368 /* Update pc to reflect the new address from which we will
2369 execute instructions. */
2370 pc
= regcache_read_pc (regcache
);
2374 /* We've already advanced the PC, so the stepping part
2375 is done. Now we need to arrange for a trap to be
2376 reported to handle_inferior_event. Set a breakpoint
2377 at the current PC, and run to it. Don't update
2378 prev_pc, because if we end in
2379 switch_back_to_stepped_thread, we want the "expected
2380 thread advanced also" branch to be taken. IOW, we
2381 don't want this thread to step further from PC
2383 gdb_assert (!step_over_info_valid_p ());
2384 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2385 insert_breakpoints ();
2387 resume_ptid
= internal_resume_ptid (user_step
);
2388 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
2395 /* If we have a breakpoint to step over, make sure to do a single
2396 step only. Same if we have software watchpoints. */
2397 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2398 tp
->control
.may_range_step
= 0;
2400 /* If enabled, step over breakpoints by executing a copy of the
2401 instruction at a different address.
2403 We can't use displaced stepping when we have a signal to deliver;
2404 the comments for displaced_step_prepare explain why. The
2405 comments in the handle_inferior event for dealing with 'random
2406 signals' explain what we do instead.
2408 We can't use displaced stepping when we are waiting for vfork_done
2409 event, displaced stepping breaks the vfork child similarly as single
2410 step software breakpoint. */
2411 if (tp
->control
.trap_expected
2412 && use_displaced_stepping (tp
)
2413 && !step_over_info_valid_p ()
2414 && sig
== GDB_SIGNAL_0
2415 && !current_inferior ()->waiting_for_vfork_done
)
2417 int prepared
= displaced_step_prepare (tp
);
2422 fprintf_unfiltered (gdb_stdlog
,
2423 "Got placed in step-over queue\n");
2425 tp
->control
.trap_expected
= 0;
2428 else if (prepared
< 0)
2430 /* Fallback to stepping over the breakpoint in-line. */
2432 if (target_is_non_stop_p ())
2433 stop_all_threads ();
2435 set_step_over_info (regcache
->aspace (),
2436 regcache_read_pc (regcache
), 0, tp
->global_num
);
2438 step
= maybe_software_singlestep (gdbarch
, pc
);
2440 insert_breakpoints ();
2442 else if (prepared
> 0)
2444 struct displaced_step_inferior_state
*displaced
;
2446 /* Update pc to reflect the new address from which we will
2447 execute instructions due to displaced stepping. */
2448 pc
= regcache_read_pc (get_thread_regcache (tp
));
2450 displaced
= get_displaced_stepping_state (tp
->inf
);
2451 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
2452 displaced
->step_closure
);
2456 /* Do we need to do it the hard way, w/temp breakpoints? */
2458 step
= maybe_software_singlestep (gdbarch
, pc
);
2460 /* Currently, our software single-step implementation leads to different
2461 results than hardware single-stepping in one situation: when stepping
2462 into delivering a signal which has an associated signal handler,
2463 hardware single-step will stop at the first instruction of the handler,
2464 while software single-step will simply skip execution of the handler.
2466 For now, this difference in behavior is accepted since there is no
2467 easy way to actually implement single-stepping into a signal handler
2468 without kernel support.
2470 However, there is one scenario where this difference leads to follow-on
2471 problems: if we're stepping off a breakpoint by removing all breakpoints
2472 and then single-stepping. In this case, the software single-step
2473 behavior means that even if there is a *breakpoint* in the signal
2474 handler, GDB still would not stop.
2476 Fortunately, we can at least fix this particular issue. We detect
2477 here the case where we are about to deliver a signal while software
2478 single-stepping with breakpoints removed. In this situation, we
2479 revert the decisions to remove all breakpoints and insert single-
2480 step breakpoints, and instead we install a step-resume breakpoint
2481 at the current address, deliver the signal without stepping, and
2482 once we arrive back at the step-resume breakpoint, actually step
2483 over the breakpoint we originally wanted to step over. */
2484 if (thread_has_single_step_breakpoints_set (tp
)
2485 && sig
!= GDB_SIGNAL_0
2486 && step_over_info_valid_p ())
2488 /* If we have nested signals or a pending signal is delivered
2489 immediately after a handler returns, might might already have
2490 a step-resume breakpoint set on the earlier handler. We cannot
2491 set another step-resume breakpoint; just continue on until the
2492 original breakpoint is hit. */
2493 if (tp
->control
.step_resume_breakpoint
== NULL
)
2495 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2496 tp
->step_after_step_resume_breakpoint
= 1;
2499 delete_single_step_breakpoints (tp
);
2501 clear_step_over_info ();
2502 tp
->control
.trap_expected
= 0;
2504 insert_breakpoints ();
2507 /* If STEP is set, it's a request to use hardware stepping
2508 facilities. But in that case, we should never
2509 use singlestep breakpoint. */
2510 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2512 /* Decide the set of threads to ask the target to resume. */
2513 if (tp
->control
.trap_expected
)
2515 /* We're allowing a thread to run past a breakpoint it has
2516 hit, either by single-stepping the thread with the breakpoint
2517 removed, or by displaced stepping, with the breakpoint inserted.
2518 In the former case, we need to single-step only this thread,
2519 and keep others stopped, as they can miss this breakpoint if
2520 allowed to run. That's not really a problem for displaced
2521 stepping, but, we still keep other threads stopped, in case
2522 another thread is also stopped for a breakpoint waiting for
2523 its turn in the displaced stepping queue. */
2524 resume_ptid
= inferior_ptid
;
2527 resume_ptid
= internal_resume_ptid (user_step
);
2529 if (execution_direction
!= EXEC_REVERSE
2530 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2532 /* There are two cases where we currently need to step a
2533 breakpoint instruction when we have a signal to deliver:
2535 - See handle_signal_stop where we handle random signals that
2536 could take out us out of the stepping range. Normally, in
2537 that case we end up continuing (instead of stepping) over the
2538 signal handler with a breakpoint at PC, but there are cases
2539 where we should _always_ single-step, even if we have a
2540 step-resume breakpoint, like when a software watchpoint is
2541 set. Assuming single-stepping and delivering a signal at the
2542 same time would takes us to the signal handler, then we could
2543 have removed the breakpoint at PC to step over it. However,
2544 some hardware step targets (like e.g., Mac OS) can't step
2545 into signal handlers, and for those, we need to leave the
2546 breakpoint at PC inserted, as otherwise if the handler
2547 recurses and executes PC again, it'll miss the breakpoint.
2548 So we leave the breakpoint inserted anyway, but we need to
2549 record that we tried to step a breakpoint instruction, so
2550 that adjust_pc_after_break doesn't end up confused.
2552 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2553 in one thread after another thread that was stepping had been
2554 momentarily paused for a step-over. When we re-resume the
2555 stepping thread, it may be resumed from that address with a
2556 breakpoint that hasn't trapped yet. Seen with
2557 gdb.threads/non-stop-fair-events.exp, on targets that don't
2558 do displaced stepping. */
2561 fprintf_unfiltered (gdb_stdlog
,
2562 "infrun: resume: [%s] stepped breakpoint\n",
2563 target_pid_to_str (tp
->ptid
).c_str ());
2565 tp
->stepped_breakpoint
= 1;
2567 /* Most targets can step a breakpoint instruction, thus
2568 executing it normally. But if this one cannot, just
2569 continue and we will hit it anyway. */
2570 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2575 && tp
->control
.trap_expected
2576 && use_displaced_stepping (tp
)
2577 && !step_over_info_valid_p ())
2579 struct regcache
*resume_regcache
= get_thread_regcache (tp
);
2580 struct gdbarch
*resume_gdbarch
= resume_regcache
->arch ();
2581 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2584 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
2585 paddress (resume_gdbarch
, actual_pc
));
2586 read_memory (actual_pc
, buf
, sizeof (buf
));
2587 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
2590 if (tp
->control
.may_range_step
)
2592 /* If we're resuming a thread with the PC out of the step
2593 range, then we're doing some nested/finer run control
2594 operation, like stepping the thread out of the dynamic
2595 linker or the displaced stepping scratch pad. We
2596 shouldn't have allowed a range step then. */
2597 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2600 do_target_resume (resume_ptid
, step
, sig
);
2604 /* Resume the inferior. SIG is the signal to give the inferior
2605 (GDB_SIGNAL_0 for none). This is a wrapper around 'resume_1' that
2606 rolls back state on error. */
2609 resume (gdb_signal sig
)
2615 CATCH (ex
, RETURN_MASK_ALL
)
2617 /* If resuming is being aborted for any reason, delete any
2618 single-step breakpoint resume_1 may have created, to avoid
2619 confusing the following resumption, and to avoid leaving
2620 single-step breakpoints perturbing other threads, in case
2621 we're running in non-stop mode. */
2622 if (inferior_ptid
!= null_ptid
)
2623 delete_single_step_breakpoints (inferior_thread ());
2624 throw_exception (ex
);
2634 /* Counter that tracks number of user visible stops. This can be used
2635 to tell whether a command has proceeded the inferior past the
2636 current location. This allows e.g., inferior function calls in
2637 breakpoint commands to not interrupt the command list. When the
2638 call finishes successfully, the inferior is standing at the same
2639 breakpoint as if nothing happened (and so we don't call
2641 static ULONGEST current_stop_id
;
2648 return current_stop_id
;
2651 /* Called when we report a user visible stop. */
2659 /* Clear out all variables saying what to do when inferior is continued.
2660 First do this, then set the ones you want, then call `proceed'. */
2663 clear_proceed_status_thread (struct thread_info
*tp
)
2666 fprintf_unfiltered (gdb_stdlog
,
2667 "infrun: clear_proceed_status_thread (%s)\n",
2668 target_pid_to_str (tp
->ptid
).c_str ());
2670 /* If we're starting a new sequence, then the previous finished
2671 single-step is no longer relevant. */
2672 if (tp
->suspend
.waitstatus_pending_p
)
2674 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
2677 fprintf_unfiltered (gdb_stdlog
,
2678 "infrun: clear_proceed_status: pending "
2679 "event of %s was a finished step. "
2681 target_pid_to_str (tp
->ptid
).c_str ());
2683 tp
->suspend
.waitstatus_pending_p
= 0;
2684 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2686 else if (debug_infrun
)
2689 = target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2691 fprintf_unfiltered (gdb_stdlog
,
2692 "infrun: clear_proceed_status_thread: thread %s "
2693 "has pending wait status %s "
2694 "(currently_stepping=%d).\n",
2695 target_pid_to_str (tp
->ptid
).c_str (),
2697 currently_stepping (tp
));
2701 /* If this signal should not be seen by program, give it zero.
2702 Used for debugging signals. */
2703 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2704 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2706 delete tp
->thread_fsm
;
2707 tp
->thread_fsm
= NULL
;
2709 tp
->control
.trap_expected
= 0;
2710 tp
->control
.step_range_start
= 0;
2711 tp
->control
.step_range_end
= 0;
2712 tp
->control
.may_range_step
= 0;
2713 tp
->control
.step_frame_id
= null_frame_id
;
2714 tp
->control
.step_stack_frame_id
= null_frame_id
;
2715 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2716 tp
->control
.step_start_function
= NULL
;
2717 tp
->stop_requested
= 0;
2719 tp
->control
.stop_step
= 0;
2721 tp
->control
.proceed_to_finish
= 0;
2723 tp
->control
.stepping_command
= 0;
2725 /* Discard any remaining commands or status from previous stop. */
2726 bpstat_clear (&tp
->control
.stop_bpstat
);
2730 clear_proceed_status (int step
)
2732 /* With scheduler-locking replay, stop replaying other threads if we're
2733 not replaying the user-visible resume ptid.
2735 This is a convenience feature to not require the user to explicitly
2736 stop replaying the other threads. We're assuming that the user's
2737 intent is to resume tracing the recorded process. */
2738 if (!non_stop
&& scheduler_mode
== schedlock_replay
2739 && target_record_is_replaying (minus_one_ptid
)
2740 && !target_record_will_replay (user_visible_resume_ptid (step
),
2741 execution_direction
))
2742 target_record_stop_replaying ();
2744 if (!non_stop
&& inferior_ptid
!= null_ptid
)
2746 ptid_t resume_ptid
= user_visible_resume_ptid (step
);
2748 /* In all-stop mode, delete the per-thread status of all threads
2749 we're about to resume, implicitly and explicitly. */
2750 for (thread_info
*tp
: all_non_exited_threads (resume_ptid
))
2751 clear_proceed_status_thread (tp
);
2754 if (inferior_ptid
!= null_ptid
)
2756 struct inferior
*inferior
;
2760 /* If in non-stop mode, only delete the per-thread status of
2761 the current thread. */
2762 clear_proceed_status_thread (inferior_thread ());
2765 inferior
= current_inferior ();
2766 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2769 gdb::observers::about_to_proceed
.notify ();
2772 /* Returns true if TP is still stopped at a breakpoint that needs
2773 stepping-over in order to make progress. If the breakpoint is gone
2774 meanwhile, we can skip the whole step-over dance. */
2777 thread_still_needs_step_over_bp (struct thread_info
*tp
)
2779 if (tp
->stepping_over_breakpoint
)
2781 struct regcache
*regcache
= get_thread_regcache (tp
);
2783 if (breakpoint_here_p (regcache
->aspace (),
2784 regcache_read_pc (regcache
))
2785 == ordinary_breakpoint_here
)
2788 tp
->stepping_over_breakpoint
= 0;
2794 /* Check whether thread TP still needs to start a step-over in order
2795 to make progress when resumed. Returns an bitwise or of enum
2796 step_over_what bits, indicating what needs to be stepped over. */
2798 static step_over_what
2799 thread_still_needs_step_over (struct thread_info
*tp
)
2801 step_over_what what
= 0;
2803 if (thread_still_needs_step_over_bp (tp
))
2804 what
|= STEP_OVER_BREAKPOINT
;
2806 if (tp
->stepping_over_watchpoint
2807 && !target_have_steppable_watchpoint
)
2808 what
|= STEP_OVER_WATCHPOINT
;
2813 /* Returns true if scheduler locking applies. STEP indicates whether
2814 we're about to do a step/next-like command to a thread. */
2817 schedlock_applies (struct thread_info
*tp
)
2819 return (scheduler_mode
== schedlock_on
2820 || (scheduler_mode
== schedlock_step
2821 && tp
->control
.stepping_command
)
2822 || (scheduler_mode
== schedlock_replay
2823 && target_record_will_replay (minus_one_ptid
,
2824 execution_direction
)));
2827 /* Basic routine for continuing the program in various fashions.
2829 ADDR is the address to resume at, or -1 for resume where stopped.
2830 SIGGNAL is the signal to give it, or GDB_SIGNAL_0 for none,
2831 or GDB_SIGNAL_DEFAULT for act according to how it stopped.
2833 You should call clear_proceed_status before calling proceed. */
2836 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
)
2838 struct regcache
*regcache
;
2839 struct gdbarch
*gdbarch
;
2842 struct execution_control_state ecss
;
2843 struct execution_control_state
*ecs
= &ecss
;
2846 /* If we're stopped at a fork/vfork, follow the branch set by the
2847 "set follow-fork-mode" command; otherwise, we'll just proceed
2848 resuming the current thread. */
2849 if (!follow_fork ())
2851 /* The target for some reason decided not to resume. */
2853 if (target_can_async_p ())
2854 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2858 /* We'll update this if & when we switch to a new thread. */
2859 previous_inferior_ptid
= inferior_ptid
;
2861 regcache
= get_current_regcache ();
2862 gdbarch
= regcache
->arch ();
2863 const address_space
*aspace
= regcache
->aspace ();
2865 pc
= regcache_read_pc (regcache
);
2866 thread_info
*cur_thr
= inferior_thread ();
2868 /* Fill in with reasonable starting values. */
2869 init_thread_stepping_state (cur_thr
);
2871 gdb_assert (!thread_is_in_step_over_chain (cur_thr
));
2873 if (addr
== (CORE_ADDR
) -1)
2875 if (pc
== cur_thr
->suspend
.stop_pc
2876 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
2877 && execution_direction
!= EXEC_REVERSE
)
2878 /* There is a breakpoint at the address we will resume at,
2879 step one instruction before inserting breakpoints so that
2880 we do not stop right away (and report a second hit at this
2883 Note, we don't do this in reverse, because we won't
2884 actually be executing the breakpoint insn anyway.
2885 We'll be (un-)executing the previous instruction. */
2886 cur_thr
->stepping_over_breakpoint
= 1;
2887 else if (gdbarch_single_step_through_delay_p (gdbarch
)
2888 && gdbarch_single_step_through_delay (gdbarch
,
2889 get_current_frame ()))
2890 /* We stepped onto an instruction that needs to be stepped
2891 again before re-inserting the breakpoint, do so. */
2892 cur_thr
->stepping_over_breakpoint
= 1;
2896 regcache_write_pc (regcache
, addr
);
2899 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
2900 cur_thr
->suspend
.stop_signal
= siggnal
;
2902 resume_ptid
= user_visible_resume_ptid (cur_thr
->control
.stepping_command
);
2904 /* If an exception is thrown from this point on, make sure to
2905 propagate GDB's knowledge of the executing state to the
2906 frontend/user running state. */
2907 scoped_finish_thread_state
finish_state (resume_ptid
);
2909 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
2910 threads (e.g., we might need to set threads stepping over
2911 breakpoints first), from the user/frontend's point of view, all
2912 threads in RESUME_PTID are now running. Unless we're calling an
2913 inferior function, as in that case we pretend the inferior
2914 doesn't run at all. */
2915 if (!cur_thr
->control
.in_infcall
)
2916 set_running (resume_ptid
, 1);
2919 fprintf_unfiltered (gdb_stdlog
,
2920 "infrun: proceed (addr=%s, signal=%s)\n",
2921 paddress (gdbarch
, addr
),
2922 gdb_signal_to_symbol_string (siggnal
));
2924 annotate_starting ();
2926 /* Make sure that output from GDB appears before output from the
2928 gdb_flush (gdb_stdout
);
2930 /* Since we've marked the inferior running, give it the terminal. A
2931 QUIT/Ctrl-C from here on is forwarded to the target (which can
2932 still detect attempts to unblock a stuck connection with repeated
2933 Ctrl-C from within target_pass_ctrlc). */
2934 target_terminal::inferior ();
2936 /* In a multi-threaded task we may select another thread and
2937 then continue or step.
2939 But if a thread that we're resuming had stopped at a breakpoint,
2940 it will immediately cause another breakpoint stop without any
2941 execution (i.e. it will report a breakpoint hit incorrectly). So
2942 we must step over it first.
2944 Look for threads other than the current (TP) that reported a
2945 breakpoint hit and haven't been resumed yet since. */
2947 /* If scheduler locking applies, we can avoid iterating over all
2949 if (!non_stop
&& !schedlock_applies (cur_thr
))
2951 for (thread_info
*tp
: all_non_exited_threads (resume_ptid
))
2953 /* Ignore the current thread here. It's handled
2958 if (!thread_still_needs_step_over (tp
))
2961 gdb_assert (!thread_is_in_step_over_chain (tp
));
2964 fprintf_unfiltered (gdb_stdlog
,
2965 "infrun: need to step-over [%s] first\n",
2966 target_pid_to_str (tp
->ptid
).c_str ());
2968 thread_step_over_chain_enqueue (tp
);
2972 /* Enqueue the current thread last, so that we move all other
2973 threads over their breakpoints first. */
2974 if (cur_thr
->stepping_over_breakpoint
)
2975 thread_step_over_chain_enqueue (cur_thr
);
2977 /* If the thread isn't started, we'll still need to set its prev_pc,
2978 so that switch_back_to_stepped_thread knows the thread hasn't
2979 advanced. Must do this before resuming any thread, as in
2980 all-stop/remote, once we resume we can't send any other packet
2981 until the target stops again. */
2982 cur_thr
->prev_pc
= regcache_read_pc (regcache
);
2985 scoped_restore save_defer_tc
= make_scoped_defer_target_commit_resume ();
2987 started
= start_step_over ();
2989 if (step_over_info_valid_p ())
2991 /* Either this thread started a new in-line step over, or some
2992 other thread was already doing one. In either case, don't
2993 resume anything else until the step-over is finished. */
2995 else if (started
&& !target_is_non_stop_p ())
2997 /* A new displaced stepping sequence was started. In all-stop,
2998 we can't talk to the target anymore until it next stops. */
3000 else if (!non_stop
&& target_is_non_stop_p ())
3002 /* In all-stop, but the target is always in non-stop mode.
3003 Start all other threads that are implicitly resumed too. */
3004 for (thread_info
*tp
: all_non_exited_threads (resume_ptid
))
3009 fprintf_unfiltered (gdb_stdlog
,
3010 "infrun: proceed: [%s] resumed\n",
3011 target_pid_to_str (tp
->ptid
).c_str ());
3012 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
3016 if (thread_is_in_step_over_chain (tp
))
3019 fprintf_unfiltered (gdb_stdlog
,
3020 "infrun: proceed: [%s] needs step-over\n",
3021 target_pid_to_str (tp
->ptid
).c_str ());
3026 fprintf_unfiltered (gdb_stdlog
,
3027 "infrun: proceed: resuming %s\n",
3028 target_pid_to_str (tp
->ptid
).c_str ());
3030 reset_ecs (ecs
, tp
);
3031 switch_to_thread (tp
);
3032 keep_going_pass_signal (ecs
);
3033 if (!ecs
->wait_some_more
)
3034 error (_("Command aborted."));
3037 else if (!cur_thr
->resumed
&& !thread_is_in_step_over_chain (cur_thr
))
3039 /* The thread wasn't started, and isn't queued, run it now. */
3040 reset_ecs (ecs
, cur_thr
);
3041 switch_to_thread (cur_thr
);
3042 keep_going_pass_signal (ecs
);
3043 if (!ecs
->wait_some_more
)
3044 error (_("Command aborted."));
3048 target_commit_resume ();
3050 finish_state
.release ();
3052 /* Tell the event loop to wait for it to stop. If the target
3053 supports asynchronous execution, it'll do this from within
3055 if (!target_can_async_p ())
3056 mark_async_event_handler (infrun_async_inferior_event_token
);
3060 /* Start remote-debugging of a machine over a serial link. */
3063 start_remote (int from_tty
)
3065 struct inferior
*inferior
;
3067 inferior
= current_inferior ();
3068 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
3070 /* Always go on waiting for the target, regardless of the mode. */
3071 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3072 indicate to wait_for_inferior that a target should timeout if
3073 nothing is returned (instead of just blocking). Because of this,
3074 targets expecting an immediate response need to, internally, set
3075 things up so that the target_wait() is forced to eventually
3077 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3078 differentiate to its caller what the state of the target is after
3079 the initial open has been performed. Here we're assuming that
3080 the target has stopped. It should be possible to eventually have
3081 target_open() return to the caller an indication that the target
3082 is currently running and GDB state should be set to the same as
3083 for an async run. */
3084 wait_for_inferior ();
3086 /* Now that the inferior has stopped, do any bookkeeping like
3087 loading shared libraries. We want to do this before normal_stop,
3088 so that the displayed frame is up to date. */
3089 post_create_inferior (current_top_target (), from_tty
);
3094 /* Initialize static vars when a new inferior begins. */
3097 init_wait_for_inferior (void)
3099 /* These are meaningless until the first time through wait_for_inferior. */
3101 breakpoint_init_inferior (inf_starting
);
3103 clear_proceed_status (0);
3105 target_last_wait_ptid
= minus_one_ptid
;
3107 previous_inferior_ptid
= inferior_ptid
;
3112 static void handle_inferior_event (struct execution_control_state
*ecs
);
3114 static void handle_step_into_function (struct gdbarch
*gdbarch
,
3115 struct execution_control_state
*ecs
);
3116 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
3117 struct execution_control_state
*ecs
);
3118 static void handle_signal_stop (struct execution_control_state
*ecs
);
3119 static void check_exception_resume (struct execution_control_state
*,
3120 struct frame_info
*);
3122 static void end_stepping_range (struct execution_control_state
*ecs
);
3123 static void stop_waiting (struct execution_control_state
*ecs
);
3124 static void keep_going (struct execution_control_state
*ecs
);
3125 static void process_event_stop_test (struct execution_control_state
*ecs
);
3126 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
3128 /* This function is attached as a "thread_stop_requested" observer.
3129 Cleanup local state that assumed the PTID was to be resumed, and
3130 report the stop to the frontend. */
3133 infrun_thread_stop_requested (ptid_t ptid
)
3135 /* PTID was requested to stop. If the thread was already stopped,
3136 but the user/frontend doesn't know about that yet (e.g., the
3137 thread had been temporarily paused for some step-over), set up
3138 for reporting the stop now. */
3139 for (thread_info
*tp
: all_threads (ptid
))
3141 if (tp
->state
!= THREAD_RUNNING
)
3146 /* Remove matching threads from the step-over queue, so
3147 start_step_over doesn't try to resume them
3149 if (thread_is_in_step_over_chain (tp
))
3150 thread_step_over_chain_remove (tp
);
3152 /* If the thread is stopped, but the user/frontend doesn't
3153 know about that yet, queue a pending event, as if the
3154 thread had just stopped now. Unless the thread already had
3156 if (!tp
->suspend
.waitstatus_pending_p
)
3158 tp
->suspend
.waitstatus_pending_p
= 1;
3159 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_STOPPED
;
3160 tp
->suspend
.waitstatus
.value
.sig
= GDB_SIGNAL_0
;
3163 /* Clear the inline-frame state, since we're re-processing the
3165 clear_inline_frame_state (tp
->ptid
);
3167 /* If this thread was paused because some other thread was
3168 doing an inline-step over, let that finish first. Once
3169 that happens, we'll restart all threads and consume pending
3170 stop events then. */
3171 if (step_over_info_valid_p ())
3174 /* Otherwise we can process the (new) pending event now. Set
3175 it so this pending event is considered by
3182 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
3184 if (target_last_wait_ptid
== tp
->ptid
)
3185 nullify_last_target_wait_ptid ();
3188 /* Delete the step resume, single-step and longjmp/exception resume
3189 breakpoints of TP. */
3192 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
3194 delete_step_resume_breakpoint (tp
);
3195 delete_exception_resume_breakpoint (tp
);
3196 delete_single_step_breakpoints (tp
);
3199 /* If the target still has execution, call FUNC for each thread that
3200 just stopped. In all-stop, that's all the non-exited threads; in
3201 non-stop, that's the current thread, only. */
3203 typedef void (*for_each_just_stopped_thread_callback_func
)
3204 (struct thread_info
*tp
);
3207 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
3209 if (!target_has_execution
|| inferior_ptid
== null_ptid
)
3212 if (target_is_non_stop_p ())
3214 /* If in non-stop mode, only the current thread stopped. */
3215 func (inferior_thread ());
3219 /* In all-stop mode, all threads have stopped. */
3220 for (thread_info
*tp
: all_non_exited_threads ())
3225 /* Delete the step resume and longjmp/exception resume breakpoints of
3226 the threads that just stopped. */
3229 delete_just_stopped_threads_infrun_breakpoints (void)
3231 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3234 /* Delete the single-step breakpoints of the threads that just
3238 delete_just_stopped_threads_single_step_breakpoints (void)
3240 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3246 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3247 const struct target_waitstatus
*ws
)
3249 std::string status_string
= target_waitstatus_to_string (ws
);
3252 /* The text is split over several lines because it was getting too long.
3253 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3254 output as a unit; we want only one timestamp printed if debug_timestamp
3257 stb
.printf ("infrun: target_wait (%d.%ld.%ld",
3260 waiton_ptid
.tid ());
3261 if (waiton_ptid
.pid () != -1)
3262 stb
.printf (" [%s]", target_pid_to_str (waiton_ptid
).c_str ());
3263 stb
.printf (", status) =\n");
3264 stb
.printf ("infrun: %d.%ld.%ld [%s],\n",
3268 target_pid_to_str (result_ptid
).c_str ());
3269 stb
.printf ("infrun: %s\n", status_string
.c_str ());
3271 /* This uses %s in part to handle %'s in the text, but also to avoid
3272 a gcc error: the format attribute requires a string literal. */
3273 fprintf_unfiltered (gdb_stdlog
, "%s", stb
.c_str ());
3276 /* Select a thread at random, out of those which are resumed and have
3279 static struct thread_info
*
3280 random_pending_event_thread (ptid_t waiton_ptid
)
3284 auto has_event
= [] (thread_info
*tp
)
3287 && tp
->suspend
.waitstatus_pending_p
);
3290 /* First see how many events we have. Count only resumed threads
3291 that have an event pending. */
3292 for (thread_info
*tp
: all_non_exited_threads (waiton_ptid
))
3296 if (num_events
== 0)
3299 /* Now randomly pick a thread out of those that have had events. */
3300 int random_selector
= (int) ((num_events
* (double) rand ())
3301 / (RAND_MAX
+ 1.0));
3303 if (debug_infrun
&& num_events
> 1)
3304 fprintf_unfiltered (gdb_stdlog
,
3305 "infrun: Found %d events, selecting #%d\n",
3306 num_events
, random_selector
);
3308 /* Select the Nth thread that has had an event. */
3309 for (thread_info
*tp
: all_non_exited_threads (waiton_ptid
))
3311 if (random_selector
-- == 0)
3314 gdb_assert_not_reached ("event thread not found");
3317 /* Wrapper for target_wait that first checks whether threads have
3318 pending statuses to report before actually asking the target for
3322 do_target_wait (ptid_t ptid
, struct target_waitstatus
*status
, int options
)
3325 struct thread_info
*tp
;
3327 /* First check if there is a resumed thread with a wait status
3329 if (ptid
== minus_one_ptid
|| ptid
.is_pid ())
3331 tp
= random_pending_event_thread (ptid
);
3336 fprintf_unfiltered (gdb_stdlog
,
3337 "infrun: Waiting for specific thread %s.\n",
3338 target_pid_to_str (ptid
).c_str ());
3340 /* We have a specific thread to check. */
3341 tp
= find_thread_ptid (ptid
);
3342 gdb_assert (tp
!= NULL
);
3343 if (!tp
->suspend
.waitstatus_pending_p
)
3348 && (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3349 || tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
3351 struct regcache
*regcache
= get_thread_regcache (tp
);
3352 struct gdbarch
*gdbarch
= regcache
->arch ();
3356 pc
= regcache_read_pc (regcache
);
3358 if (pc
!= tp
->suspend
.stop_pc
)
3361 fprintf_unfiltered (gdb_stdlog
,
3362 "infrun: PC of %s changed. was=%s, now=%s\n",
3363 target_pid_to_str (tp
->ptid
).c_str (),
3364 paddress (gdbarch
, tp
->suspend
.stop_pc
),
3365 paddress (gdbarch
, pc
));
3368 else if (!breakpoint_inserted_here_p (regcache
->aspace (), pc
))
3371 fprintf_unfiltered (gdb_stdlog
,
3372 "infrun: previous breakpoint of %s, at %s gone\n",
3373 target_pid_to_str (tp
->ptid
).c_str (),
3374 paddress (gdbarch
, pc
));
3382 fprintf_unfiltered (gdb_stdlog
,
3383 "infrun: pending event of %s cancelled.\n",
3384 target_pid_to_str (tp
->ptid
).c_str ());
3386 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_SPURIOUS
;
3387 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3396 = target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
3398 fprintf_unfiltered (gdb_stdlog
,
3399 "infrun: Using pending wait status %s for %s.\n",
3401 target_pid_to_str (tp
->ptid
).c_str ());
3404 /* Now that we've selected our final event LWP, un-adjust its PC
3405 if it was a software breakpoint (and the target doesn't
3406 always adjust the PC itself). */
3407 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3408 && !target_supports_stopped_by_sw_breakpoint ())
3410 struct regcache
*regcache
;
3411 struct gdbarch
*gdbarch
;
3414 regcache
= get_thread_regcache (tp
);
3415 gdbarch
= regcache
->arch ();
3417 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3422 pc
= regcache_read_pc (regcache
);
3423 regcache_write_pc (regcache
, pc
+ decr_pc
);
3427 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3428 *status
= tp
->suspend
.waitstatus
;
3429 tp
->suspend
.waitstatus_pending_p
= 0;
3431 /* Wake up the event loop again, until all pending events are
3433 if (target_is_async_p ())
3434 mark_async_event_handler (infrun_async_inferior_event_token
);
3438 /* But if we don't find one, we'll have to wait. */
3440 if (deprecated_target_wait_hook
)
3441 event_ptid
= deprecated_target_wait_hook (ptid
, status
, options
);
3443 event_ptid
= target_wait (ptid
, status
, options
);
3448 /* Prepare and stabilize the inferior for detaching it. E.g.,
3449 detaching while a thread is displaced stepping is a recipe for
3450 crashing it, as nothing would readjust the PC out of the scratch
3454 prepare_for_detach (void)
3456 struct inferior
*inf
= current_inferior ();
3457 ptid_t pid_ptid
= ptid_t (inf
->pid
);
3459 displaced_step_inferior_state
*displaced
= get_displaced_stepping_state (inf
);
3461 /* Is any thread of this process displaced stepping? If not,
3462 there's nothing else to do. */
3463 if (displaced
->step_thread
== nullptr)
3467 fprintf_unfiltered (gdb_stdlog
,
3468 "displaced-stepping in-process while detaching");
3470 scoped_restore restore_detaching
= make_scoped_restore (&inf
->detaching
, true);
3472 while (displaced
->step_thread
!= nullptr)
3474 struct execution_control_state ecss
;
3475 struct execution_control_state
*ecs
;
3478 memset (ecs
, 0, sizeof (*ecs
));
3480 overlay_cache_invalid
= 1;
3481 /* Flush target cache before starting to handle each event.
3482 Target was running and cache could be stale. This is just a
3483 heuristic. Running threads may modify target memory, but we
3484 don't get any event. */
3485 target_dcache_invalidate ();
3487 ecs
->ptid
= do_target_wait (pid_ptid
, &ecs
->ws
, 0);
3490 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
3492 /* If an error happens while handling the event, propagate GDB's
3493 knowledge of the executing state to the frontend/user running
3495 scoped_finish_thread_state
finish_state (minus_one_ptid
);
3497 /* Now figure out what to do with the result of the result. */
3498 handle_inferior_event (ecs
);
3500 /* No error, don't finish the state yet. */
3501 finish_state
.release ();
3503 /* Breakpoints and watchpoints are not installed on the target
3504 at this point, and signals are passed directly to the
3505 inferior, so this must mean the process is gone. */
3506 if (!ecs
->wait_some_more
)
3508 restore_detaching
.release ();
3509 error (_("Program exited while detaching"));
3513 restore_detaching
.release ();
3516 /* Wait for control to return from inferior to debugger.
3518 If inferior gets a signal, we may decide to start it up again
3519 instead of returning. That is why there is a loop in this function.
3520 When this function actually returns it means the inferior
3521 should be left stopped and GDB should read more commands. */
3524 wait_for_inferior (void)
3528 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
3530 SCOPE_EXIT
{ delete_just_stopped_threads_infrun_breakpoints (); };
3532 /* If an error happens while handling the event, propagate GDB's
3533 knowledge of the executing state to the frontend/user running
3535 scoped_finish_thread_state
finish_state (minus_one_ptid
);
3539 struct execution_control_state ecss
;
3540 struct execution_control_state
*ecs
= &ecss
;
3541 ptid_t waiton_ptid
= minus_one_ptid
;
3543 memset (ecs
, 0, sizeof (*ecs
));
3545 overlay_cache_invalid
= 1;
3547 /* Flush target cache before starting to handle each event.
3548 Target was running and cache could be stale. This is just a
3549 heuristic. Running threads may modify target memory, but we
3550 don't get any event. */
3551 target_dcache_invalidate ();
3553 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
, 0);
3556 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3558 /* Now figure out what to do with the result of the result. */
3559 handle_inferior_event (ecs
);
3561 if (!ecs
->wait_some_more
)
3565 /* No error, don't finish the state yet. */
3566 finish_state
.release ();
3569 /* Cleanup that reinstalls the readline callback handler, if the
3570 target is running in the background. If while handling the target
3571 event something triggered a secondary prompt, like e.g., a
3572 pagination prompt, we'll have removed the callback handler (see
3573 gdb_readline_wrapper_line). Need to do this as we go back to the
3574 event loop, ready to process further input. Note this has no
3575 effect if the handler hasn't actually been removed, because calling
3576 rl_callback_handler_install resets the line buffer, thus losing
3580 reinstall_readline_callback_handler_cleanup ()
3582 struct ui
*ui
= current_ui
;
3586 /* We're not going back to the top level event loop yet. Don't
3587 install the readline callback, as it'd prep the terminal,
3588 readline-style (raw, noecho) (e.g., --batch). We'll install
3589 it the next time the prompt is displayed, when we're ready
3594 if (ui
->command_editing
&& ui
->prompt_state
!= PROMPT_BLOCKED
)
3595 gdb_rl_callback_handler_reinstall ();
3598 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3599 that's just the event thread. In all-stop, that's all threads. */
3602 clean_up_just_stopped_threads_fsms (struct execution_control_state
*ecs
)
3604 if (ecs
->event_thread
!= NULL
3605 && ecs
->event_thread
->thread_fsm
!= NULL
)
3606 ecs
->event_thread
->thread_fsm
->clean_up (ecs
->event_thread
);
3610 for (thread_info
*thr
: all_non_exited_threads ())
3612 if (thr
->thread_fsm
== NULL
)
3614 if (thr
== ecs
->event_thread
)
3617 switch_to_thread (thr
);
3618 thr
->thread_fsm
->clean_up (thr
);
3621 if (ecs
->event_thread
!= NULL
)
3622 switch_to_thread (ecs
->event_thread
);
3626 /* Helper for all_uis_check_sync_execution_done that works on the
3630 check_curr_ui_sync_execution_done (void)
3632 struct ui
*ui
= current_ui
;
3634 if (ui
->prompt_state
== PROMPT_NEEDED
3636 && !gdb_in_secondary_prompt_p (ui
))
3638 target_terminal::ours ();
3639 gdb::observers::sync_execution_done
.notify ();
3640 ui_register_input_event_handler (ui
);
3647 all_uis_check_sync_execution_done (void)
3649 SWITCH_THRU_ALL_UIS ()
3651 check_curr_ui_sync_execution_done ();
3658 all_uis_on_sync_execution_starting (void)
3660 SWITCH_THRU_ALL_UIS ()
3662 if (current_ui
->prompt_state
== PROMPT_NEEDED
)
3663 async_disable_stdin ();
3667 /* Asynchronous version of wait_for_inferior. It is called by the
3668 event loop whenever a change of state is detected on the file
3669 descriptor corresponding to the target. It can be called more than
3670 once to complete a single execution command. In such cases we need
3671 to keep the state in a global variable ECSS. If it is the last time
3672 that this function is called for a single execution command, then
3673 report to the user that the inferior has stopped, and do the
3674 necessary cleanups. */
3677 fetch_inferior_event (void *client_data
)
3679 struct execution_control_state ecss
;
3680 struct execution_control_state
*ecs
= &ecss
;
3682 ptid_t waiton_ptid
= minus_one_ptid
;
3684 memset (ecs
, 0, sizeof (*ecs
));
3686 /* Events are always processed with the main UI as current UI. This
3687 way, warnings, debug output, etc. are always consistently sent to
3688 the main console. */
3689 scoped_restore save_ui
= make_scoped_restore (¤t_ui
, main_ui
);
3691 /* End up with readline processing input, if necessary. */
3693 SCOPE_EXIT
{ reinstall_readline_callback_handler_cleanup (); };
3695 /* We're handling a live event, so make sure we're doing live
3696 debugging. If we're looking at traceframes while the target is
3697 running, we're going to need to get back to that mode after
3698 handling the event. */
3699 gdb::optional
<scoped_restore_current_traceframe
> maybe_restore_traceframe
;
3702 maybe_restore_traceframe
.emplace ();
3703 set_current_traceframe (-1);
3706 gdb::optional
<scoped_restore_current_thread
> maybe_restore_thread
;
3709 /* In non-stop mode, the user/frontend should not notice a thread
3710 switch due to internal events. Make sure we reverse to the
3711 user selected thread and frame after handling the event and
3712 running any breakpoint commands. */
3713 maybe_restore_thread
.emplace ();
3715 overlay_cache_invalid
= 1;
3716 /* Flush target cache before starting to handle each event. Target
3717 was running and cache could be stale. This is just a heuristic.
3718 Running threads may modify target memory, but we don't get any
3720 target_dcache_invalidate ();
3722 scoped_restore save_exec_dir
3723 = make_scoped_restore (&execution_direction
,
3724 target_execution_direction ());
3726 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
,
3727 target_can_async_p () ? TARGET_WNOHANG
: 0);
3730 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3732 /* If an error happens while handling the event, propagate GDB's
3733 knowledge of the executing state to the frontend/user running
3735 ptid_t finish_ptid
= !target_is_non_stop_p () ? minus_one_ptid
: ecs
->ptid
;
3736 scoped_finish_thread_state
finish_state (finish_ptid
);
3738 /* Get executed before scoped_restore_current_thread above to apply
3739 still for the thread which has thrown the exception. */
3740 auto defer_bpstat_clear
3741 = make_scope_exit (bpstat_clear_actions
);
3742 auto defer_delete_threads
3743 = make_scope_exit (delete_just_stopped_threads_infrun_breakpoints
);
3745 /* Now figure out what to do with the result of the result. */
3746 handle_inferior_event (ecs
);
3748 if (!ecs
->wait_some_more
)
3750 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
3751 int should_stop
= 1;
3752 struct thread_info
*thr
= ecs
->event_thread
;
3754 delete_just_stopped_threads_infrun_breakpoints ();
3758 struct thread_fsm
*thread_fsm
= thr
->thread_fsm
;
3760 if (thread_fsm
!= NULL
)
3761 should_stop
= thread_fsm
->should_stop (thr
);
3770 bool should_notify_stop
= true;
3773 clean_up_just_stopped_threads_fsms (ecs
);
3775 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3776 should_notify_stop
= thr
->thread_fsm
->should_notify_stop ();
3778 if (should_notify_stop
)
3780 /* We may not find an inferior if this was a process exit. */
3781 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
3782 proceeded
= normal_stop ();
3787 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3793 defer_delete_threads
.release ();
3794 defer_bpstat_clear
.release ();
3796 /* No error, don't finish the thread states yet. */
3797 finish_state
.release ();
3799 /* This scope is used to ensure that readline callbacks are
3800 reinstalled here. */
3803 /* If a UI was in sync execution mode, and now isn't, restore its
3804 prompt (a synchronous execution command has finished, and we're
3805 ready for input). */
3806 all_uis_check_sync_execution_done ();
3809 && exec_done_display_p
3810 && (inferior_ptid
== null_ptid
3811 || inferior_thread ()->state
!= THREAD_RUNNING
))
3812 printf_unfiltered (_("completed.\n"));
3815 /* Record the frame and location we're currently stepping through. */
3817 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
3819 struct thread_info
*tp
= inferior_thread ();
3821 tp
->control
.step_frame_id
= get_frame_id (frame
);
3822 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
3824 tp
->current_symtab
= sal
.symtab
;
3825 tp
->current_line
= sal
.line
;
3828 /* Clear context switchable stepping state. */
3831 init_thread_stepping_state (struct thread_info
*tss
)
3833 tss
->stepped_breakpoint
= 0;
3834 tss
->stepping_over_breakpoint
= 0;
3835 tss
->stepping_over_watchpoint
= 0;
3836 tss
->step_after_step_resume_breakpoint
= 0;
3839 /* Set the cached copy of the last ptid/waitstatus. */
3842 set_last_target_status (ptid_t ptid
, struct target_waitstatus status
)
3844 target_last_wait_ptid
= ptid
;
3845 target_last_waitstatus
= status
;
3848 /* Return the cached copy of the last pid/waitstatus returned by
3849 target_wait()/deprecated_target_wait_hook(). The data is actually
3850 cached by handle_inferior_event(), which gets called immediately
3851 after target_wait()/deprecated_target_wait_hook(). */
3854 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
3856 *ptidp
= target_last_wait_ptid
;
3857 *status
= target_last_waitstatus
;
3861 nullify_last_target_wait_ptid (void)
3863 target_last_wait_ptid
= minus_one_ptid
;
3866 /* Switch thread contexts. */
3869 context_switch (execution_control_state
*ecs
)
3872 && ecs
->ptid
!= inferior_ptid
3873 && ecs
->event_thread
!= inferior_thread ())
3875 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
3876 target_pid_to_str (inferior_ptid
).c_str ());
3877 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
3878 target_pid_to_str (ecs
->ptid
).c_str ());
3881 switch_to_thread (ecs
->event_thread
);
3884 /* If the target can't tell whether we've hit breakpoints
3885 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
3886 check whether that could have been caused by a breakpoint. If so,
3887 adjust the PC, per gdbarch_decr_pc_after_break. */
3890 adjust_pc_after_break (struct thread_info
*thread
,
3891 struct target_waitstatus
*ws
)
3893 struct regcache
*regcache
;
3894 struct gdbarch
*gdbarch
;
3895 CORE_ADDR breakpoint_pc
, decr_pc
;
3897 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
3898 we aren't, just return.
3900 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
3901 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
3902 implemented by software breakpoints should be handled through the normal
3905 NOTE drow/2004-01-31: On some targets, breakpoints may generate
3906 different signals (SIGILL or SIGEMT for instance), but it is less
3907 clear where the PC is pointing afterwards. It may not match
3908 gdbarch_decr_pc_after_break. I don't know any specific target that
3909 generates these signals at breakpoints (the code has been in GDB since at
3910 least 1992) so I can not guess how to handle them here.
3912 In earlier versions of GDB, a target with
3913 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
3914 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
3915 target with both of these set in GDB history, and it seems unlikely to be
3916 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
3918 if (ws
->kind
!= TARGET_WAITKIND_STOPPED
)
3921 if (ws
->value
.sig
!= GDB_SIGNAL_TRAP
)
3924 /* In reverse execution, when a breakpoint is hit, the instruction
3925 under it has already been de-executed. The reported PC always
3926 points at the breakpoint address, so adjusting it further would
3927 be wrong. E.g., consider this case on a decr_pc_after_break == 1
3930 B1 0x08000000 : INSN1
3931 B2 0x08000001 : INSN2
3933 PC -> 0x08000003 : INSN4
3935 Say you're stopped at 0x08000003 as above. Reverse continuing
3936 from that point should hit B2 as below. Reading the PC when the
3937 SIGTRAP is reported should read 0x08000001 and INSN2 should have
3938 been de-executed already.
3940 B1 0x08000000 : INSN1
3941 B2 PC -> 0x08000001 : INSN2
3945 We can't apply the same logic as for forward execution, because
3946 we would wrongly adjust the PC to 0x08000000, since there's a
3947 breakpoint at PC - 1. We'd then report a hit on B1, although
3948 INSN1 hadn't been de-executed yet. Doing nothing is the correct
3950 if (execution_direction
== EXEC_REVERSE
)
3953 /* If the target can tell whether the thread hit a SW breakpoint,
3954 trust it. Targets that can tell also adjust the PC
3956 if (target_supports_stopped_by_sw_breakpoint ())
3959 /* Note that relying on whether a breakpoint is planted in memory to
3960 determine this can fail. E.g,. the breakpoint could have been
3961 removed since. Or the thread could have been told to step an
3962 instruction the size of a breakpoint instruction, and only
3963 _after_ was a breakpoint inserted at its address. */
3965 /* If this target does not decrement the PC after breakpoints, then
3966 we have nothing to do. */
3967 regcache
= get_thread_regcache (thread
);
3968 gdbarch
= regcache
->arch ();
3970 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3974 const address_space
*aspace
= regcache
->aspace ();
3976 /* Find the location where (if we've hit a breakpoint) the
3977 breakpoint would be. */
3978 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
3980 /* If the target can't tell whether a software breakpoint triggered,
3981 fallback to figuring it out based on breakpoints we think were
3982 inserted in the target, and on whether the thread was stepped or
3985 /* Check whether there actually is a software breakpoint inserted at
3988 If in non-stop mode, a race condition is possible where we've
3989 removed a breakpoint, but stop events for that breakpoint were
3990 already queued and arrive later. To suppress those spurious
3991 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
3992 and retire them after a number of stop events are reported. Note
3993 this is an heuristic and can thus get confused. The real fix is
3994 to get the "stopped by SW BP and needs adjustment" info out of
3995 the target/kernel (and thus never reach here; see above). */
3996 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
3997 || (target_is_non_stop_p ()
3998 && moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
4000 gdb::optional
<scoped_restore_tmpl
<int>> restore_operation_disable
;
4002 if (record_full_is_used ())
4003 restore_operation_disable
.emplace
4004 (record_full_gdb_operation_disable_set ());
4006 /* When using hardware single-step, a SIGTRAP is reported for both
4007 a completed single-step and a software breakpoint. Need to
4008 differentiate between the two, as the latter needs adjusting
4009 but the former does not.
4011 The SIGTRAP can be due to a completed hardware single-step only if
4012 - we didn't insert software single-step breakpoints
4013 - this thread is currently being stepped
4015 If any of these events did not occur, we must have stopped due
4016 to hitting a software breakpoint, and have to back up to the
4019 As a special case, we could have hardware single-stepped a
4020 software breakpoint. In this case (prev_pc == breakpoint_pc),
4021 we also need to back up to the breakpoint address. */
4023 if (thread_has_single_step_breakpoints_set (thread
)
4024 || !currently_stepping (thread
)
4025 || (thread
->stepped_breakpoint
4026 && thread
->prev_pc
== breakpoint_pc
))
4027 regcache_write_pc (regcache
, breakpoint_pc
);
4032 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
4034 for (frame
= get_prev_frame (frame
);
4036 frame
= get_prev_frame (frame
))
4038 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
4040 if (get_frame_type (frame
) != INLINE_FRAME
)
4047 /* If the event thread has the stop requested flag set, pretend it
4048 stopped for a GDB_SIGNAL_0 (i.e., as if it stopped due to
4052 handle_stop_requested (struct execution_control_state
*ecs
)
4054 if (ecs
->event_thread
->stop_requested
)
4056 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
4057 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
4058 handle_signal_stop (ecs
);
4064 /* Auxiliary function that handles syscall entry/return events.
4065 It returns 1 if the inferior should keep going (and GDB
4066 should ignore the event), or 0 if the event deserves to be
4070 handle_syscall_event (struct execution_control_state
*ecs
)
4072 struct regcache
*regcache
;
4075 context_switch (ecs
);
4077 regcache
= get_thread_regcache (ecs
->event_thread
);
4078 syscall_number
= ecs
->ws
.value
.syscall_number
;
4079 ecs
->event_thread
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4081 if (catch_syscall_enabled () > 0
4082 && catching_syscall_number (syscall_number
) > 0)
4085 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
4088 ecs
->event_thread
->control
.stop_bpstat
4089 = bpstat_stop_status (regcache
->aspace (),
4090 ecs
->event_thread
->suspend
.stop_pc
,
4091 ecs
->event_thread
, &ecs
->ws
);
4093 if (handle_stop_requested (ecs
))
4096 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4098 /* Catchpoint hit. */
4103 if (handle_stop_requested (ecs
))
4106 /* If no catchpoint triggered for this, then keep going. */
4111 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4114 fill_in_stop_func (struct gdbarch
*gdbarch
,
4115 struct execution_control_state
*ecs
)
4117 if (!ecs
->stop_func_filled_in
)
4119 /* Don't care about return value; stop_func_start and stop_func_name
4120 will both be 0 if it doesn't work. */
4121 find_function_entry_range_from_pc (ecs
->event_thread
->suspend
.stop_pc
,
4122 &ecs
->stop_func_name
,
4123 &ecs
->stop_func_start
,
4124 &ecs
->stop_func_end
);
4125 ecs
->stop_func_start
4126 += gdbarch_deprecated_function_start_offset (gdbarch
);
4128 if (gdbarch_skip_entrypoint_p (gdbarch
))
4129 ecs
->stop_func_start
= gdbarch_skip_entrypoint (gdbarch
,
4130 ecs
->stop_func_start
);
4132 ecs
->stop_func_filled_in
= 1;
4137 /* Return the STOP_SOON field of the inferior pointed at by ECS. */
4139 static enum stop_kind
4140 get_inferior_stop_soon (execution_control_state
*ecs
)
4142 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
4144 gdb_assert (inf
!= NULL
);
4145 return inf
->control
.stop_soon
;
4148 /* Wait for one event. Store the resulting waitstatus in WS, and
4149 return the event ptid. */
4152 wait_one (struct target_waitstatus
*ws
)
4155 ptid_t wait_ptid
= minus_one_ptid
;
4157 overlay_cache_invalid
= 1;
4159 /* Flush target cache before starting to handle each event.
4160 Target was running and cache could be stale. This is just a
4161 heuristic. Running threads may modify target memory, but we
4162 don't get any event. */
4163 target_dcache_invalidate ();
4165 if (deprecated_target_wait_hook
)
4166 event_ptid
= deprecated_target_wait_hook (wait_ptid
, ws
, 0);
4168 event_ptid
= target_wait (wait_ptid
, ws
, 0);
4171 print_target_wait_results (wait_ptid
, event_ptid
, ws
);
4176 /* Generate a wrapper for target_stopped_by_REASON that works on PTID
4177 instead of the current thread. */
4178 #define THREAD_STOPPED_BY(REASON) \
4180 thread_stopped_by_ ## REASON (ptid_t ptid) \
4182 scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid); \
4183 inferior_ptid = ptid; \
4185 return target_stopped_by_ ## REASON (); \
4188 /* Generate thread_stopped_by_watchpoint. */
4189 THREAD_STOPPED_BY (watchpoint
)
4190 /* Generate thread_stopped_by_sw_breakpoint. */
4191 THREAD_STOPPED_BY (sw_breakpoint
)
4192 /* Generate thread_stopped_by_hw_breakpoint. */
4193 THREAD_STOPPED_BY (hw_breakpoint
)
4195 /* Save the thread's event and stop reason to process it later. */
4198 save_waitstatus (struct thread_info
*tp
, struct target_waitstatus
*ws
)
4202 std::string statstr
= target_waitstatus_to_string (ws
);
4204 fprintf_unfiltered (gdb_stdlog
,
4205 "infrun: saving status %s for %d.%ld.%ld\n",
4212 /* Record for later. */
4213 tp
->suspend
.waitstatus
= *ws
;
4214 tp
->suspend
.waitstatus_pending_p
= 1;
4216 struct regcache
*regcache
= get_thread_regcache (tp
);
4217 const address_space
*aspace
= regcache
->aspace ();
4219 if (ws
->kind
== TARGET_WAITKIND_STOPPED
4220 && ws
->value
.sig
== GDB_SIGNAL_TRAP
)
4222 CORE_ADDR pc
= regcache_read_pc (regcache
);
4224 adjust_pc_after_break (tp
, &tp
->suspend
.waitstatus
);
4226 if (thread_stopped_by_watchpoint (tp
->ptid
))
4228 tp
->suspend
.stop_reason
4229 = TARGET_STOPPED_BY_WATCHPOINT
;
4231 else if (target_supports_stopped_by_sw_breakpoint ()
4232 && thread_stopped_by_sw_breakpoint (tp
->ptid
))
4234 tp
->suspend
.stop_reason
4235 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4237 else if (target_supports_stopped_by_hw_breakpoint ()
4238 && thread_stopped_by_hw_breakpoint (tp
->ptid
))
4240 tp
->suspend
.stop_reason
4241 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4243 else if (!target_supports_stopped_by_hw_breakpoint ()
4244 && hardware_breakpoint_inserted_here_p (aspace
,
4247 tp
->suspend
.stop_reason
4248 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4250 else if (!target_supports_stopped_by_sw_breakpoint ()
4251 && software_breakpoint_inserted_here_p (aspace
,
4254 tp
->suspend
.stop_reason
4255 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4257 else if (!thread_has_single_step_breakpoints_set (tp
)
4258 && currently_stepping (tp
))
4260 tp
->suspend
.stop_reason
4261 = TARGET_STOPPED_BY_SINGLE_STEP
;
4269 stop_all_threads (void)
4271 /* We may need multiple passes to discover all threads. */
4275 gdb_assert (target_is_non_stop_p ());
4278 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads\n");
4280 scoped_restore_current_thread restore_thread
;
4282 target_thread_events (1);
4283 SCOPE_EXIT
{ target_thread_events (0); };
4285 /* Request threads to stop, and then wait for the stops. Because
4286 threads we already know about can spawn more threads while we're
4287 trying to stop them, and we only learn about new threads when we
4288 update the thread list, do this in a loop, and keep iterating
4289 until two passes find no threads that need to be stopped. */
4290 for (pass
= 0; pass
< 2; pass
++, iterations
++)
4293 fprintf_unfiltered (gdb_stdlog
,
4294 "infrun: stop_all_threads, pass=%d, "
4295 "iterations=%d\n", pass
, iterations
);
4299 struct target_waitstatus ws
;
4302 update_thread_list ();
4304 /* Go through all threads looking for threads that we need
4305 to tell the target to stop. */
4306 for (thread_info
*t
: all_non_exited_threads ())
4310 /* If already stopping, don't request a stop again.
4311 We just haven't seen the notification yet. */
4312 if (!t
->stop_requested
)
4315 fprintf_unfiltered (gdb_stdlog
,
4316 "infrun: %s executing, "
4318 target_pid_to_str (t
->ptid
).c_str ());
4319 target_stop (t
->ptid
);
4320 t
->stop_requested
= 1;
4325 fprintf_unfiltered (gdb_stdlog
,
4326 "infrun: %s executing, "
4327 "already stopping\n",
4328 target_pid_to_str (t
->ptid
).c_str ());
4331 if (t
->stop_requested
)
4337 fprintf_unfiltered (gdb_stdlog
,
4338 "infrun: %s not executing\n",
4339 target_pid_to_str (t
->ptid
).c_str ());
4341 /* The thread may be not executing, but still be
4342 resumed with a pending status to process. */
4350 /* If we find new threads on the second iteration, restart
4351 over. We want to see two iterations in a row with all
4356 event_ptid
= wait_one (&ws
);
4358 if (ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4360 /* All resumed threads exited. */
4362 else if (ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
4363 || ws
.kind
== TARGET_WAITKIND_EXITED
4364 || ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
4368 ptid_t ptid
= ptid_t (ws
.value
.integer
);
4370 fprintf_unfiltered (gdb_stdlog
,
4371 "infrun: %s exited while "
4372 "stopping threads\n",
4373 target_pid_to_str (ptid
).c_str ());
4378 thread_info
*t
= find_thread_ptid (event_ptid
);
4380 t
= add_thread (event_ptid
);
4382 t
->stop_requested
= 0;
4385 t
->control
.may_range_step
= 0;
4387 /* This may be the first time we see the inferior report
4389 inferior
*inf
= find_inferior_ptid (event_ptid
);
4390 if (inf
->needs_setup
)
4392 switch_to_thread_no_regs (t
);
4396 if (ws
.kind
== TARGET_WAITKIND_STOPPED
4397 && ws
.value
.sig
== GDB_SIGNAL_0
)
4399 /* We caught the event that we intended to catch, so
4400 there's no event pending. */
4401 t
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
4402 t
->suspend
.waitstatus_pending_p
= 0;
4404 if (displaced_step_fixup (t
, GDB_SIGNAL_0
) < 0)
4406 /* Add it back to the step-over queue. */
4409 fprintf_unfiltered (gdb_stdlog
,
4410 "infrun: displaced-step of %s "
4411 "canceled: adding back to the "
4412 "step-over queue\n",
4413 target_pid_to_str (t
->ptid
).c_str ());
4415 t
->control
.trap_expected
= 0;
4416 thread_step_over_chain_enqueue (t
);
4421 enum gdb_signal sig
;
4422 struct regcache
*regcache
;
4426 std::string statstr
= target_waitstatus_to_string (&ws
);
4428 fprintf_unfiltered (gdb_stdlog
,
4429 "infrun: target_wait %s, saving "
4430 "status for %d.%ld.%ld\n",
4437 /* Record for later. */
4438 save_waitstatus (t
, &ws
);
4440 sig
= (ws
.kind
== TARGET_WAITKIND_STOPPED
4441 ? ws
.value
.sig
: GDB_SIGNAL_0
);
4443 if (displaced_step_fixup (t
, sig
) < 0)
4445 /* Add it back to the step-over queue. */
4446 t
->control
.trap_expected
= 0;
4447 thread_step_over_chain_enqueue (t
);
4450 regcache
= get_thread_regcache (t
);
4451 t
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4455 fprintf_unfiltered (gdb_stdlog
,
4456 "infrun: saved stop_pc=%s for %s "
4457 "(currently_stepping=%d)\n",
4458 paddress (target_gdbarch (),
4459 t
->suspend
.stop_pc
),
4460 target_pid_to_str (t
->ptid
).c_str (),
4461 currently_stepping (t
));
4469 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads done\n");
4472 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
4475 handle_no_resumed (struct execution_control_state
*ecs
)
4477 if (target_can_async_p ())
4484 if (ui
->prompt_state
== PROMPT_BLOCKED
)
4492 /* There were no unwaited-for children left in the target, but,
4493 we're not synchronously waiting for events either. Just
4497 fprintf_unfiltered (gdb_stdlog
,
4498 "infrun: TARGET_WAITKIND_NO_RESUMED "
4499 "(ignoring: bg)\n");
4500 prepare_to_wait (ecs
);
4505 /* Otherwise, if we were running a synchronous execution command, we
4506 may need to cancel it and give the user back the terminal.
4508 In non-stop mode, the target can't tell whether we've already
4509 consumed previous stop events, so it can end up sending us a
4510 no-resumed event like so:
4512 #0 - thread 1 is left stopped
4514 #1 - thread 2 is resumed and hits breakpoint
4515 -> TARGET_WAITKIND_STOPPED
4517 #2 - thread 3 is resumed and exits
4518 this is the last resumed thread, so
4519 -> TARGET_WAITKIND_NO_RESUMED
4521 #3 - gdb processes stop for thread 2 and decides to re-resume
4524 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
4525 thread 2 is now resumed, so the event should be ignored.
4527 IOW, if the stop for thread 2 doesn't end a foreground command,
4528 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
4529 event. But it could be that the event meant that thread 2 itself
4530 (or whatever other thread was the last resumed thread) exited.
4532 To address this we refresh the thread list and check whether we
4533 have resumed threads _now_. In the example above, this removes
4534 thread 3 from the thread list. If thread 2 was re-resumed, we
4535 ignore this event. If we find no thread resumed, then we cancel
4536 the synchronous command show "no unwaited-for " to the user. */
4537 update_thread_list ();
4539 for (thread_info
*thread
: all_non_exited_threads ())
4541 if (thread
->executing
4542 || thread
->suspend
.waitstatus_pending_p
)
4544 /* There were no unwaited-for children left in the target at
4545 some point, but there are now. Just ignore. */
4547 fprintf_unfiltered (gdb_stdlog
,
4548 "infrun: TARGET_WAITKIND_NO_RESUMED "
4549 "(ignoring: found resumed)\n");
4550 prepare_to_wait (ecs
);
4555 /* Note however that we may find no resumed thread because the whole
4556 process exited meanwhile (thus updating the thread list results
4557 in an empty thread list). In this case we know we'll be getting
4558 a process exit event shortly. */
4559 for (inferior
*inf
: all_inferiors ())
4564 thread_info
*thread
= any_live_thread_of_inferior (inf
);
4568 fprintf_unfiltered (gdb_stdlog
,
4569 "infrun: TARGET_WAITKIND_NO_RESUMED "
4570 "(expect process exit)\n");
4571 prepare_to_wait (ecs
);
4576 /* Go ahead and report the event. */
4580 /* Given an execution control state that has been freshly filled in by
4581 an event from the inferior, figure out what it means and take
4584 The alternatives are:
4586 1) stop_waiting and return; to really stop and return to the
4589 2) keep_going and return; to wait for the next event (set
4590 ecs->event_thread->stepping_over_breakpoint to 1 to single step
4594 handle_inferior_event (struct execution_control_state
*ecs
)
4596 /* Make sure that all temporary struct value objects that were
4597 created during the handling of the event get deleted at the
4599 scoped_value_mark free_values
;
4601 enum stop_kind stop_soon
;
4603 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
4605 /* We had an event in the inferior, but we are not interested in
4606 handling it at this level. The lower layers have already
4607 done what needs to be done, if anything.
4609 One of the possible circumstances for this is when the
4610 inferior produces output for the console. The inferior has
4611 not stopped, and we are ignoring the event. Another possible
4612 circumstance is any event which the lower level knows will be
4613 reported multiple times without an intervening resume. */
4615 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_IGNORE\n");
4616 prepare_to_wait (ecs
);
4620 if (ecs
->ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
)
4623 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_THREAD_EXITED\n");
4624 prepare_to_wait (ecs
);
4628 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
4629 && handle_no_resumed (ecs
))
4632 /* Cache the last pid/waitstatus. */
4633 set_last_target_status (ecs
->ptid
, ecs
->ws
);
4635 /* Always clear state belonging to the previous time we stopped. */
4636 stop_stack_dummy
= STOP_NONE
;
4638 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4640 /* No unwaited-for children left. IOW, all resumed children
4643 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_RESUMED\n");
4645 stop_print_frame
= 0;
4650 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
4651 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
4653 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
4654 /* If it's a new thread, add it to the thread database. */
4655 if (ecs
->event_thread
== NULL
)
4656 ecs
->event_thread
= add_thread (ecs
->ptid
);
4658 /* Disable range stepping. If the next step request could use a
4659 range, this will be end up re-enabled then. */
4660 ecs
->event_thread
->control
.may_range_step
= 0;
4663 /* Dependent on valid ECS->EVENT_THREAD. */
4664 adjust_pc_after_break (ecs
->event_thread
, &ecs
->ws
);
4666 /* Dependent on the current PC value modified by adjust_pc_after_break. */
4667 reinit_frame_cache ();
4669 breakpoint_retire_moribund ();
4671 /* First, distinguish signals caused by the debugger from signals
4672 that have to do with the program's own actions. Note that
4673 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
4674 on the operating system version. Here we detect when a SIGILL or
4675 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
4676 something similar for SIGSEGV, since a SIGSEGV will be generated
4677 when we're trying to execute a breakpoint instruction on a
4678 non-executable stack. This happens for call dummy breakpoints
4679 for architectures like SPARC that place call dummies on the
4681 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
4682 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
4683 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
4684 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
4686 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
4688 if (breakpoint_inserted_here_p (regcache
->aspace (),
4689 regcache_read_pc (regcache
)))
4692 fprintf_unfiltered (gdb_stdlog
,
4693 "infrun: Treating signal as SIGTRAP\n");
4694 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
4698 /* Mark the non-executing threads accordingly. In all-stop, all
4699 threads of all processes are stopped when we get any event
4700 reported. In non-stop mode, only the event thread stops. */
4704 if (!target_is_non_stop_p ())
4705 mark_ptid
= minus_one_ptid
;
4706 else if (ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
4707 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4709 /* If we're handling a process exit in non-stop mode, even
4710 though threads haven't been deleted yet, one would think
4711 that there is nothing to do, as threads of the dead process
4712 will be soon deleted, and threads of any other process were
4713 left running. However, on some targets, threads survive a
4714 process exit event. E.g., for the "checkpoint" command,
4715 when the current checkpoint/fork exits, linux-fork.c
4716 automatically switches to another fork from within
4717 target_mourn_inferior, by associating the same
4718 inferior/thread to another fork. We haven't mourned yet at
4719 this point, but we must mark any threads left in the
4720 process as not-executing so that finish_thread_state marks
4721 them stopped (in the user's perspective) if/when we present
4722 the stop to the user. */
4723 mark_ptid
= ptid_t (ecs
->ptid
.pid ());
4726 mark_ptid
= ecs
->ptid
;
4728 set_executing (mark_ptid
, 0);
4730 /* Likewise the resumed flag. */
4731 set_resumed (mark_ptid
, 0);
4734 switch (ecs
->ws
.kind
)
4736 case TARGET_WAITKIND_LOADED
:
4738 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_LOADED\n");
4739 context_switch (ecs
);
4740 /* Ignore gracefully during startup of the inferior, as it might
4741 be the shell which has just loaded some objects, otherwise
4742 add the symbols for the newly loaded objects. Also ignore at
4743 the beginning of an attach or remote session; we will query
4744 the full list of libraries once the connection is
4747 stop_soon
= get_inferior_stop_soon (ecs
);
4748 if (stop_soon
== NO_STOP_QUIETLY
)
4750 struct regcache
*regcache
;
4752 regcache
= get_thread_regcache (ecs
->event_thread
);
4754 handle_solib_event ();
4756 ecs
->event_thread
->control
.stop_bpstat
4757 = bpstat_stop_status (regcache
->aspace (),
4758 ecs
->event_thread
->suspend
.stop_pc
,
4759 ecs
->event_thread
, &ecs
->ws
);
4761 if (handle_stop_requested (ecs
))
4764 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4766 /* A catchpoint triggered. */
4767 process_event_stop_test (ecs
);
4771 /* If requested, stop when the dynamic linker notifies
4772 gdb of events. This allows the user to get control
4773 and place breakpoints in initializer routines for
4774 dynamically loaded objects (among other things). */
4775 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4776 if (stop_on_solib_events
)
4778 /* Make sure we print "Stopped due to solib-event" in
4780 stop_print_frame
= 1;
4787 /* If we are skipping through a shell, or through shared library
4788 loading that we aren't interested in, resume the program. If
4789 we're running the program normally, also resume. */
4790 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
4792 /* Loading of shared libraries might have changed breakpoint
4793 addresses. Make sure new breakpoints are inserted. */
4794 if (stop_soon
== NO_STOP_QUIETLY
)
4795 insert_breakpoints ();
4796 resume (GDB_SIGNAL_0
);
4797 prepare_to_wait (ecs
);
4801 /* But stop if we're attaching or setting up a remote
4803 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4804 || stop_soon
== STOP_QUIETLY_REMOTE
)
4807 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
4812 internal_error (__FILE__
, __LINE__
,
4813 _("unhandled stop_soon: %d"), (int) stop_soon
);
4815 case TARGET_WAITKIND_SPURIOUS
:
4817 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_SPURIOUS\n");
4818 if (handle_stop_requested (ecs
))
4820 context_switch (ecs
);
4821 resume (GDB_SIGNAL_0
);
4822 prepare_to_wait (ecs
);
4825 case TARGET_WAITKIND_THREAD_CREATED
:
4827 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_THREAD_CREATED\n");
4828 if (handle_stop_requested (ecs
))
4830 context_switch (ecs
);
4831 if (!switch_back_to_stepped_thread (ecs
))
4835 case TARGET_WAITKIND_EXITED
:
4836 case TARGET_WAITKIND_SIGNALLED
:
4839 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4840 fprintf_unfiltered (gdb_stdlog
,
4841 "infrun: TARGET_WAITKIND_EXITED\n");
4843 fprintf_unfiltered (gdb_stdlog
,
4844 "infrun: TARGET_WAITKIND_SIGNALLED\n");
4847 inferior_ptid
= ecs
->ptid
;
4848 set_current_inferior (find_inferior_ptid (ecs
->ptid
));
4849 set_current_program_space (current_inferior ()->pspace
);
4850 handle_vfork_child_exec_or_exit (0);
4851 target_terminal::ours (); /* Must do this before mourn anyway. */
4853 /* Clearing any previous state of convenience variables. */
4854 clear_exit_convenience_vars ();
4856 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4858 /* Record the exit code in the convenience variable $_exitcode, so
4859 that the user can inspect this again later. */
4860 set_internalvar_integer (lookup_internalvar ("_exitcode"),
4861 (LONGEST
) ecs
->ws
.value
.integer
);
4863 /* Also record this in the inferior itself. */
4864 current_inferior ()->has_exit_code
= 1;
4865 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
4867 /* Support the --return-child-result option. */
4868 return_child_result_value
= ecs
->ws
.value
.integer
;
4870 gdb::observers::exited
.notify (ecs
->ws
.value
.integer
);
4874 struct gdbarch
*gdbarch
= current_inferior ()->gdbarch
;
4876 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
4878 /* Set the value of the internal variable $_exitsignal,
4879 which holds the signal uncaught by the inferior. */
4880 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
4881 gdbarch_gdb_signal_to_target (gdbarch
,
4882 ecs
->ws
.value
.sig
));
4886 /* We don't have access to the target's method used for
4887 converting between signal numbers (GDB's internal
4888 representation <-> target's representation).
4889 Therefore, we cannot do a good job at displaying this
4890 information to the user. It's better to just warn
4891 her about it (if infrun debugging is enabled), and
4894 fprintf_filtered (gdb_stdlog
, _("\
4895 Cannot fill $_exitsignal with the correct signal number.\n"));
4898 gdb::observers::signal_exited
.notify (ecs
->ws
.value
.sig
);
4901 gdb_flush (gdb_stdout
);
4902 target_mourn_inferior (inferior_ptid
);
4903 stop_print_frame
= 0;
4907 /* The following are the only cases in which we keep going;
4908 the above cases end in a continue or goto. */
4909 case TARGET_WAITKIND_FORKED
:
4910 case TARGET_WAITKIND_VFORKED
:
4913 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
4914 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_FORKED\n");
4916 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_VFORKED\n");
4919 /* Check whether the inferior is displaced stepping. */
4921 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
4922 struct gdbarch
*gdbarch
= regcache
->arch ();
4924 /* If checking displaced stepping is supported, and thread
4925 ecs->ptid is displaced stepping. */
4926 if (displaced_step_in_progress_thread (ecs
->event_thread
))
4928 struct inferior
*parent_inf
4929 = find_inferior_ptid (ecs
->ptid
);
4930 struct regcache
*child_regcache
;
4931 CORE_ADDR parent_pc
;
4933 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
4934 indicating that the displaced stepping of syscall instruction
4935 has been done. Perform cleanup for parent process here. Note
4936 that this operation also cleans up the child process for vfork,
4937 because their pages are shared. */
4938 displaced_step_fixup (ecs
->event_thread
, GDB_SIGNAL_TRAP
);
4939 /* Start a new step-over in another thread if there's one
4943 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
4945 struct displaced_step_inferior_state
*displaced
4946 = get_displaced_stepping_state (parent_inf
);
4948 /* Restore scratch pad for child process. */
4949 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
4952 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
4953 the child's PC is also within the scratchpad. Set the child's PC
4954 to the parent's PC value, which has already been fixed up.
4955 FIXME: we use the parent's aspace here, although we're touching
4956 the child, because the child hasn't been added to the inferior
4957 list yet at this point. */
4960 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
4962 parent_inf
->aspace
);
4963 /* Read PC value of parent process. */
4964 parent_pc
= regcache_read_pc (regcache
);
4966 if (debug_displaced
)
4967 fprintf_unfiltered (gdb_stdlog
,
4968 "displaced: write child pc from %s to %s\n",
4970 regcache_read_pc (child_regcache
)),
4971 paddress (gdbarch
, parent_pc
));
4973 regcache_write_pc (child_regcache
, parent_pc
);
4977 context_switch (ecs
);
4979 /* Immediately detach breakpoints from the child before there's
4980 any chance of letting the user delete breakpoints from the
4981 breakpoint lists. If we don't do this early, it's easy to
4982 leave left over traps in the child, vis: "break foo; catch
4983 fork; c; <fork>; del; c; <child calls foo>". We only follow
4984 the fork on the last `continue', and by that time the
4985 breakpoint at "foo" is long gone from the breakpoint table.
4986 If we vforked, then we don't need to unpatch here, since both
4987 parent and child are sharing the same memory pages; we'll
4988 need to unpatch at follow/detach time instead to be certain
4989 that new breakpoints added between catchpoint hit time and
4990 vfork follow are detached. */
4991 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
4993 /* This won't actually modify the breakpoint list, but will
4994 physically remove the breakpoints from the child. */
4995 detach_breakpoints (ecs
->ws
.value
.related_pid
);
4998 delete_just_stopped_threads_single_step_breakpoints ();
5000 /* In case the event is caught by a catchpoint, remember that
5001 the event is to be followed at the next resume of the thread,
5002 and not immediately. */
5003 ecs
->event_thread
->pending_follow
= ecs
->ws
;
5005 ecs
->event_thread
->suspend
.stop_pc
5006 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
5008 ecs
->event_thread
->control
.stop_bpstat
5009 = bpstat_stop_status (get_current_regcache ()->aspace (),
5010 ecs
->event_thread
->suspend
.stop_pc
,
5011 ecs
->event_thread
, &ecs
->ws
);
5013 if (handle_stop_requested (ecs
))
5016 /* If no catchpoint triggered for this, then keep going. Note
5017 that we're interested in knowing the bpstat actually causes a
5018 stop, not just if it may explain the signal. Software
5019 watchpoints, for example, always appear in the bpstat. */
5020 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5024 = (follow_fork_mode_string
== follow_fork_mode_child
);
5026 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5028 should_resume
= follow_fork ();
5030 thread_info
*parent
= ecs
->event_thread
;
5031 thread_info
*child
= find_thread_ptid (ecs
->ws
.value
.related_pid
);
5033 /* At this point, the parent is marked running, and the
5034 child is marked stopped. */
5036 /* If not resuming the parent, mark it stopped. */
5037 if (follow_child
&& !detach_fork
&& !non_stop
&& !sched_multi
)
5038 parent
->set_running (false);
5040 /* If resuming the child, mark it running. */
5041 if (follow_child
|| (!detach_fork
&& (non_stop
|| sched_multi
)))
5042 child
->set_running (true);
5044 /* In non-stop mode, also resume the other branch. */
5045 if (!detach_fork
&& (non_stop
5046 || (sched_multi
&& target_is_non_stop_p ())))
5049 switch_to_thread (parent
);
5051 switch_to_thread (child
);
5053 ecs
->event_thread
= inferior_thread ();
5054 ecs
->ptid
= inferior_ptid
;
5059 switch_to_thread (child
);
5061 switch_to_thread (parent
);
5063 ecs
->event_thread
= inferior_thread ();
5064 ecs
->ptid
= inferior_ptid
;
5072 process_event_stop_test (ecs
);
5075 case TARGET_WAITKIND_VFORK_DONE
:
5076 /* Done with the shared memory region. Re-insert breakpoints in
5077 the parent, and keep going. */
5080 fprintf_unfiltered (gdb_stdlog
,
5081 "infrun: TARGET_WAITKIND_VFORK_DONE\n");
5083 context_switch (ecs
);
5085 current_inferior ()->waiting_for_vfork_done
= 0;
5086 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
5088 if (handle_stop_requested (ecs
))
5091 /* This also takes care of reinserting breakpoints in the
5092 previously locked inferior. */
5096 case TARGET_WAITKIND_EXECD
:
5098 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_EXECD\n");
5100 /* Note we can't read registers yet (the stop_pc), because we
5101 don't yet know the inferior's post-exec architecture.
5102 'stop_pc' is explicitly read below instead. */
5103 switch_to_thread_no_regs (ecs
->event_thread
);
5105 /* Do whatever is necessary to the parent branch of the vfork. */
5106 handle_vfork_child_exec_or_exit (1);
5108 /* This causes the eventpoints and symbol table to be reset.
5109 Must do this now, before trying to determine whether to
5111 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
5113 /* In follow_exec we may have deleted the original thread and
5114 created a new one. Make sure that the event thread is the
5115 execd thread for that case (this is a nop otherwise). */
5116 ecs
->event_thread
= inferior_thread ();
5118 ecs
->event_thread
->suspend
.stop_pc
5119 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
5121 ecs
->event_thread
->control
.stop_bpstat
5122 = bpstat_stop_status (get_current_regcache ()->aspace (),
5123 ecs
->event_thread
->suspend
.stop_pc
,
5124 ecs
->event_thread
, &ecs
->ws
);
5126 /* Note that this may be referenced from inside
5127 bpstat_stop_status above, through inferior_has_execd. */
5128 xfree (ecs
->ws
.value
.execd_pathname
);
5129 ecs
->ws
.value
.execd_pathname
= NULL
;
5131 if (handle_stop_requested (ecs
))
5134 /* If no catchpoint triggered for this, then keep going. */
5135 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5137 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5141 process_event_stop_test (ecs
);
5144 /* Be careful not to try to gather much state about a thread
5145 that's in a syscall. It's frequently a losing proposition. */
5146 case TARGET_WAITKIND_SYSCALL_ENTRY
:
5148 fprintf_unfiltered (gdb_stdlog
,
5149 "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
5150 /* Getting the current syscall number. */
5151 if (handle_syscall_event (ecs
) == 0)
5152 process_event_stop_test (ecs
);
5155 /* Before examining the threads further, step this thread to
5156 get it entirely out of the syscall. (We get notice of the
5157 event when the thread is just on the verge of exiting a
5158 syscall. Stepping one instruction seems to get it back
5160 case TARGET_WAITKIND_SYSCALL_RETURN
:
5162 fprintf_unfiltered (gdb_stdlog
,
5163 "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
5164 if (handle_syscall_event (ecs
) == 0)
5165 process_event_stop_test (ecs
);
5168 case TARGET_WAITKIND_STOPPED
:
5170 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_STOPPED\n");
5171 handle_signal_stop (ecs
);
5174 case TARGET_WAITKIND_NO_HISTORY
:
5176 fprintf_unfiltered (gdb_stdlog
, "infrun: TARGET_WAITKIND_NO_HISTORY\n");
5177 /* Reverse execution: target ran out of history info. */
5179 /* Switch to the stopped thread. */
5180 context_switch (ecs
);
5182 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
5184 delete_just_stopped_threads_single_step_breakpoints ();
5185 ecs
->event_thread
->suspend
.stop_pc
5186 = regcache_read_pc (get_thread_regcache (inferior_thread ()));
5188 if (handle_stop_requested (ecs
))
5191 gdb::observers::no_history
.notify ();
5197 /* Restart threads back to what they were trying to do back when we
5198 paused them for an in-line step-over. The EVENT_THREAD thread is
5202 restart_threads (struct thread_info
*event_thread
)
5204 /* In case the instruction just stepped spawned a new thread. */
5205 update_thread_list ();
5207 for (thread_info
*tp
: all_non_exited_threads ())
5209 if (tp
== event_thread
)
5212 fprintf_unfiltered (gdb_stdlog
,
5213 "infrun: restart threads: "
5214 "[%s] is event thread\n",
5215 target_pid_to_str (tp
->ptid
).c_str ());
5219 if (!(tp
->state
== THREAD_RUNNING
|| tp
->control
.in_infcall
))
5222 fprintf_unfiltered (gdb_stdlog
,
5223 "infrun: restart threads: "
5224 "[%s] not meant to be running\n",
5225 target_pid_to_str (tp
->ptid
).c_str ());
5232 fprintf_unfiltered (gdb_stdlog
,
5233 "infrun: restart threads: [%s] resumed\n",
5234 target_pid_to_str (tp
->ptid
).c_str ());
5235 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
5239 if (thread_is_in_step_over_chain (tp
))
5242 fprintf_unfiltered (gdb_stdlog
,
5243 "infrun: restart threads: "
5244 "[%s] needs step-over\n",
5245 target_pid_to_str (tp
->ptid
).c_str ());
5246 gdb_assert (!tp
->resumed
);
5251 if (tp
->suspend
.waitstatus_pending_p
)
5254 fprintf_unfiltered (gdb_stdlog
,
5255 "infrun: restart threads: "
5256 "[%s] has pending status\n",
5257 target_pid_to_str (tp
->ptid
).c_str ());
5262 gdb_assert (!tp
->stop_requested
);
5264 /* If some thread needs to start a step-over at this point, it
5265 should still be in the step-over queue, and thus skipped
5267 if (thread_still_needs_step_over (tp
))
5269 internal_error (__FILE__
, __LINE__
,
5270 "thread [%s] needs a step-over, but not in "
5271 "step-over queue\n",
5272 target_pid_to_str (tp
->ptid
).c_str ());
5275 if (currently_stepping (tp
))
5278 fprintf_unfiltered (gdb_stdlog
,
5279 "infrun: restart threads: [%s] was stepping\n",
5280 target_pid_to_str (tp
->ptid
).c_str ());
5281 keep_going_stepped_thread (tp
);
5285 struct execution_control_state ecss
;
5286 struct execution_control_state
*ecs
= &ecss
;
5289 fprintf_unfiltered (gdb_stdlog
,
5290 "infrun: restart threads: [%s] continuing\n",
5291 target_pid_to_str (tp
->ptid
).c_str ());
5292 reset_ecs (ecs
, tp
);
5293 switch_to_thread (tp
);
5294 keep_going_pass_signal (ecs
);
5299 /* Callback for iterate_over_threads. Find a resumed thread that has
5300 a pending waitstatus. */
5303 resumed_thread_with_pending_status (struct thread_info
*tp
,
5307 && tp
->suspend
.waitstatus_pending_p
);
5310 /* Called when we get an event that may finish an in-line or
5311 out-of-line (displaced stepping) step-over started previously.
5312 Return true if the event is processed and we should go back to the
5313 event loop; false if the caller should continue processing the
5317 finish_step_over (struct execution_control_state
*ecs
)
5319 int had_step_over_info
;
5321 displaced_step_fixup (ecs
->event_thread
,
5322 ecs
->event_thread
->suspend
.stop_signal
);
5324 had_step_over_info
= step_over_info_valid_p ();
5326 if (had_step_over_info
)
5328 /* If we're stepping over a breakpoint with all threads locked,
5329 then only the thread that was stepped should be reporting
5331 gdb_assert (ecs
->event_thread
->control
.trap_expected
);
5333 clear_step_over_info ();
5336 if (!target_is_non_stop_p ())
5339 /* Start a new step-over in another thread if there's one that
5343 /* If we were stepping over a breakpoint before, and haven't started
5344 a new in-line step-over sequence, then restart all other threads
5345 (except the event thread). We can't do this in all-stop, as then
5346 e.g., we wouldn't be able to issue any other remote packet until
5347 these other threads stop. */
5348 if (had_step_over_info
&& !step_over_info_valid_p ())
5350 struct thread_info
*pending
;
5352 /* If we only have threads with pending statuses, the restart
5353 below won't restart any thread and so nothing re-inserts the
5354 breakpoint we just stepped over. But we need it inserted
5355 when we later process the pending events, otherwise if
5356 another thread has a pending event for this breakpoint too,
5357 we'd discard its event (because the breakpoint that
5358 originally caused the event was no longer inserted). */
5359 context_switch (ecs
);
5360 insert_breakpoints ();
5362 restart_threads (ecs
->event_thread
);
5364 /* If we have events pending, go through handle_inferior_event
5365 again, picking up a pending event at random. This avoids
5366 thread starvation. */
5368 /* But not if we just stepped over a watchpoint in order to let
5369 the instruction execute so we can evaluate its expression.
5370 The set of watchpoints that triggered is recorded in the
5371 breakpoint objects themselves (see bp->watchpoint_triggered).
5372 If we processed another event first, that other event could
5373 clobber this info. */
5374 if (ecs
->event_thread
->stepping_over_watchpoint
)
5377 pending
= iterate_over_threads (resumed_thread_with_pending_status
,
5379 if (pending
!= NULL
)
5381 struct thread_info
*tp
= ecs
->event_thread
;
5382 struct regcache
*regcache
;
5386 fprintf_unfiltered (gdb_stdlog
,
5387 "infrun: found resumed threads with "
5388 "pending events, saving status\n");
5391 gdb_assert (pending
!= tp
);
5393 /* Record the event thread's event for later. */
5394 save_waitstatus (tp
, &ecs
->ws
);
5395 /* This was cleared early, by handle_inferior_event. Set it
5396 so this pending event is considered by
5400 gdb_assert (!tp
->executing
);
5402 regcache
= get_thread_regcache (tp
);
5403 tp
->suspend
.stop_pc
= regcache_read_pc (regcache
);
5407 fprintf_unfiltered (gdb_stdlog
,
5408 "infrun: saved stop_pc=%s for %s "
5409 "(currently_stepping=%d)\n",
5410 paddress (target_gdbarch (),
5411 tp
->suspend
.stop_pc
),
5412 target_pid_to_str (tp
->ptid
).c_str (),
5413 currently_stepping (tp
));
5416 /* This in-line step-over finished; clear this so we won't
5417 start a new one. This is what handle_signal_stop would
5418 do, if we returned false. */
5419 tp
->stepping_over_breakpoint
= 0;
5421 /* Wake up the event loop again. */
5422 mark_async_event_handler (infrun_async_inferior_event_token
);
5424 prepare_to_wait (ecs
);
5432 /* Come here when the program has stopped with a signal. */
5435 handle_signal_stop (struct execution_control_state
*ecs
)
5437 struct frame_info
*frame
;
5438 struct gdbarch
*gdbarch
;
5439 int stopped_by_watchpoint
;
5440 enum stop_kind stop_soon
;
5443 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
5445 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
5447 /* Do we need to clean up the state of a thread that has
5448 completed a displaced single-step? (Doing so usually affects
5449 the PC, so do it here, before we set stop_pc.) */
5450 if (finish_step_over (ecs
))
5453 /* If we either finished a single-step or hit a breakpoint, but
5454 the user wanted this thread to be stopped, pretend we got a
5455 SIG0 (generic unsignaled stop). */
5456 if (ecs
->event_thread
->stop_requested
5457 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5458 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5460 ecs
->event_thread
->suspend
.stop_pc
5461 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
5465 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
5466 struct gdbarch
*reg_gdbarch
= regcache
->arch ();
5467 scoped_restore save_inferior_ptid
= make_scoped_restore (&inferior_ptid
);
5469 inferior_ptid
= ecs
->ptid
;
5471 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
5472 paddress (reg_gdbarch
,
5473 ecs
->event_thread
->suspend
.stop_pc
));
5474 if (target_stopped_by_watchpoint ())
5478 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
5480 if (target_stopped_data_address (current_top_target (), &addr
))
5481 fprintf_unfiltered (gdb_stdlog
,
5482 "infrun: stopped data address = %s\n",
5483 paddress (reg_gdbarch
, addr
));
5485 fprintf_unfiltered (gdb_stdlog
,
5486 "infrun: (no data address available)\n");
5490 /* This is originated from start_remote(), start_inferior() and
5491 shared libraries hook functions. */
5492 stop_soon
= get_inferior_stop_soon (ecs
);
5493 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
5495 context_switch (ecs
);
5497 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5498 stop_print_frame
= 1;
5503 /* This originates from attach_command(). We need to overwrite
5504 the stop_signal here, because some kernels don't ignore a
5505 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5506 See more comments in inferior.h. On the other hand, if we
5507 get a non-SIGSTOP, report it to the user - assume the backend
5508 will handle the SIGSTOP if it should show up later.
5510 Also consider that the attach is complete when we see a
5511 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5512 target extended-remote report it instead of a SIGSTOP
5513 (e.g. gdbserver). We already rely on SIGTRAP being our
5514 signal, so this is no exception.
5516 Also consider that the attach is complete when we see a
5517 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5518 the target to stop all threads of the inferior, in case the
5519 low level attach operation doesn't stop them implicitly. If
5520 they weren't stopped implicitly, then the stub will report a
5521 GDB_SIGNAL_0, meaning: stopped for no particular reason
5522 other than GDB's request. */
5523 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5524 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
5525 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5526 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
5528 stop_print_frame
= 1;
5530 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5534 /* See if something interesting happened to the non-current thread. If
5535 so, then switch to that thread. */
5536 if (ecs
->ptid
!= inferior_ptid
)
5539 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
5541 context_switch (ecs
);
5543 if (deprecated_context_hook
)
5544 deprecated_context_hook (ecs
->event_thread
->global_num
);
5547 /* At this point, get hold of the now-current thread's frame. */
5548 frame
= get_current_frame ();
5549 gdbarch
= get_frame_arch (frame
);
5551 /* Pull the single step breakpoints out of the target. */
5552 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5554 struct regcache
*regcache
;
5557 regcache
= get_thread_regcache (ecs
->event_thread
);
5558 const address_space
*aspace
= regcache
->aspace ();
5560 pc
= regcache_read_pc (regcache
);
5562 /* However, before doing so, if this single-step breakpoint was
5563 actually for another thread, set this thread up for moving
5565 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
5568 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
5572 fprintf_unfiltered (gdb_stdlog
,
5573 "infrun: [%s] hit another thread's "
5574 "single-step breakpoint\n",
5575 target_pid_to_str (ecs
->ptid
).c_str ());
5577 ecs
->hit_singlestep_breakpoint
= 1;
5584 fprintf_unfiltered (gdb_stdlog
,
5585 "infrun: [%s] hit its "
5586 "single-step breakpoint\n",
5587 target_pid_to_str (ecs
->ptid
).c_str ());
5591 delete_just_stopped_threads_single_step_breakpoints ();
5593 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5594 && ecs
->event_thread
->control
.trap_expected
5595 && ecs
->event_thread
->stepping_over_watchpoint
)
5596 stopped_by_watchpoint
= 0;
5598 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
5600 /* If necessary, step over this watchpoint. We'll be back to display
5602 if (stopped_by_watchpoint
5603 && (target_have_steppable_watchpoint
5604 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
5606 /* At this point, we are stopped at an instruction which has
5607 attempted to write to a piece of memory under control of
5608 a watchpoint. The instruction hasn't actually executed
5609 yet. If we were to evaluate the watchpoint expression
5610 now, we would get the old value, and therefore no change
5611 would seem to have occurred.
5613 In order to make watchpoints work `right', we really need
5614 to complete the memory write, and then evaluate the
5615 watchpoint expression. We do this by single-stepping the
5618 It may not be necessary to disable the watchpoint to step over
5619 it. For example, the PA can (with some kernel cooperation)
5620 single step over a watchpoint without disabling the watchpoint.
5622 It is far more common to need to disable a watchpoint to step
5623 the inferior over it. If we have non-steppable watchpoints,
5624 we must disable the current watchpoint; it's simplest to
5625 disable all watchpoints.
5627 Any breakpoint at PC must also be stepped over -- if there's
5628 one, it will have already triggered before the watchpoint
5629 triggered, and we either already reported it to the user, or
5630 it didn't cause a stop and we called keep_going. In either
5631 case, if there was a breakpoint at PC, we must be trying to
5633 ecs
->event_thread
->stepping_over_watchpoint
= 1;
5638 ecs
->event_thread
->stepping_over_breakpoint
= 0;
5639 ecs
->event_thread
->stepping_over_watchpoint
= 0;
5640 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
5641 ecs
->event_thread
->control
.stop_step
= 0;
5642 stop_print_frame
= 1;
5643 stopped_by_random_signal
= 0;
5644 bpstat stop_chain
= NULL
;
5646 /* Hide inlined functions starting here, unless we just performed stepi or
5647 nexti. After stepi and nexti, always show the innermost frame (not any
5648 inline function call sites). */
5649 if (ecs
->event_thread
->control
.step_range_end
!= 1)
5651 const address_space
*aspace
5652 = get_thread_regcache (ecs
->event_thread
)->aspace ();
5654 /* skip_inline_frames is expensive, so we avoid it if we can
5655 determine that the address is one where functions cannot have
5656 been inlined. This improves performance with inferiors that
5657 load a lot of shared libraries, because the solib event
5658 breakpoint is defined as the address of a function (i.e. not
5659 inline). Note that we have to check the previous PC as well
5660 as the current one to catch cases when we have just
5661 single-stepped off a breakpoint prior to reinstating it.
5662 Note that we're assuming that the code we single-step to is
5663 not inline, but that's not definitive: there's nothing
5664 preventing the event breakpoint function from containing
5665 inlined code, and the single-step ending up there. If the
5666 user had set a breakpoint on that inlined code, the missing
5667 skip_inline_frames call would break things. Fortunately
5668 that's an extremely unlikely scenario. */
5669 if (!pc_at_non_inline_function (aspace
,
5670 ecs
->event_thread
->suspend
.stop_pc
,
5672 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5673 && ecs
->event_thread
->control
.trap_expected
5674 && pc_at_non_inline_function (aspace
,
5675 ecs
->event_thread
->prev_pc
,
5678 stop_chain
= build_bpstat_chain (aspace
,
5679 ecs
->event_thread
->suspend
.stop_pc
,
5681 skip_inline_frames (ecs
->event_thread
, stop_chain
);
5683 /* Re-fetch current thread's frame in case that invalidated
5685 frame
= get_current_frame ();
5686 gdbarch
= get_frame_arch (frame
);
5690 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5691 && ecs
->event_thread
->control
.trap_expected
5692 && gdbarch_single_step_through_delay_p (gdbarch
)
5693 && currently_stepping (ecs
->event_thread
))
5695 /* We're trying to step off a breakpoint. Turns out that we're
5696 also on an instruction that needs to be stepped multiple
5697 times before it's been fully executing. E.g., architectures
5698 with a delay slot. It needs to be stepped twice, once for
5699 the instruction and once for the delay slot. */
5700 int step_through_delay
5701 = gdbarch_single_step_through_delay (gdbarch
, frame
);
5703 if (debug_infrun
&& step_through_delay
)
5704 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
5705 if (ecs
->event_thread
->control
.step_range_end
== 0
5706 && step_through_delay
)
5708 /* The user issued a continue when stopped at a breakpoint.
5709 Set up for another trap and get out of here. */
5710 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5714 else if (step_through_delay
)
5716 /* The user issued a step when stopped at a breakpoint.
5717 Maybe we should stop, maybe we should not - the delay
5718 slot *might* correspond to a line of source. In any
5719 case, don't decide that here, just set
5720 ecs->stepping_over_breakpoint, making sure we
5721 single-step again before breakpoints are re-inserted. */
5722 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5726 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
5727 handles this event. */
5728 ecs
->event_thread
->control
.stop_bpstat
5729 = bpstat_stop_status (get_current_regcache ()->aspace (),
5730 ecs
->event_thread
->suspend
.stop_pc
,
5731 ecs
->event_thread
, &ecs
->ws
, stop_chain
);
5733 /* Following in case break condition called a
5735 stop_print_frame
= 1;
5737 /* This is where we handle "moribund" watchpoints. Unlike
5738 software breakpoints traps, hardware watchpoint traps are
5739 always distinguishable from random traps. If no high-level
5740 watchpoint is associated with the reported stop data address
5741 anymore, then the bpstat does not explain the signal ---
5742 simply make sure to ignore it if `stopped_by_watchpoint' is
5746 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5747 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5749 && stopped_by_watchpoint
)
5750 fprintf_unfiltered (gdb_stdlog
,
5751 "infrun: no user watchpoint explains "
5752 "watchpoint SIGTRAP, ignoring\n");
5754 /* NOTE: cagney/2003-03-29: These checks for a random signal
5755 at one stage in the past included checks for an inferior
5756 function call's call dummy's return breakpoint. The original
5757 comment, that went with the test, read:
5759 ``End of a stack dummy. Some systems (e.g. Sony news) give
5760 another signal besides SIGTRAP, so check here as well as
5763 If someone ever tries to get call dummys on a
5764 non-executable stack to work (where the target would stop
5765 with something like a SIGSEGV), then those tests might need
5766 to be re-instated. Given, however, that the tests were only
5767 enabled when momentary breakpoints were not being used, I
5768 suspect that it won't be the case.
5770 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
5771 be necessary for call dummies on a non-executable stack on
5774 /* See if the breakpoints module can explain the signal. */
5776 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5777 ecs
->event_thread
->suspend
.stop_signal
);
5779 /* Maybe this was a trap for a software breakpoint that has since
5781 if (random_signal
&& target_stopped_by_sw_breakpoint ())
5783 if (program_breakpoint_here_p (gdbarch
,
5784 ecs
->event_thread
->suspend
.stop_pc
))
5786 struct regcache
*regcache
;
5789 /* Re-adjust PC to what the program would see if GDB was not
5791 regcache
= get_thread_regcache (ecs
->event_thread
);
5792 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
5795 gdb::optional
<scoped_restore_tmpl
<int>>
5796 restore_operation_disable
;
5798 if (record_full_is_used ())
5799 restore_operation_disable
.emplace
5800 (record_full_gdb_operation_disable_set ());
5802 regcache_write_pc (regcache
,
5803 ecs
->event_thread
->suspend
.stop_pc
+ decr_pc
);
5808 /* A delayed software breakpoint event. Ignore the trap. */
5810 fprintf_unfiltered (gdb_stdlog
,
5811 "infrun: delayed software breakpoint "
5812 "trap, ignoring\n");
5817 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
5818 has since been removed. */
5819 if (random_signal
&& target_stopped_by_hw_breakpoint ())
5821 /* A delayed hardware breakpoint event. Ignore the trap. */
5823 fprintf_unfiltered (gdb_stdlog
,
5824 "infrun: delayed hardware breakpoint/watchpoint "
5825 "trap, ignoring\n");
5829 /* If not, perhaps stepping/nexting can. */
5831 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5832 && currently_stepping (ecs
->event_thread
));
5834 /* Perhaps the thread hit a single-step breakpoint of _another_
5835 thread. Single-step breakpoints are transparent to the
5836 breakpoints module. */
5838 random_signal
= !ecs
->hit_singlestep_breakpoint
;
5840 /* No? Perhaps we got a moribund watchpoint. */
5842 random_signal
= !stopped_by_watchpoint
;
5844 /* Always stop if the user explicitly requested this thread to
5846 if (ecs
->event_thread
->stop_requested
)
5850 fprintf_unfiltered (gdb_stdlog
, "infrun: user-requested stop\n");
5853 /* For the program's own signals, act according to
5854 the signal handling tables. */
5858 /* Signal not for debugging purposes. */
5859 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
5860 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
5863 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
5864 gdb_signal_to_symbol_string (stop_signal
));
5866 stopped_by_random_signal
= 1;
5868 /* Always stop on signals if we're either just gaining control
5869 of the program, or the user explicitly requested this thread
5870 to remain stopped. */
5871 if (stop_soon
!= NO_STOP_QUIETLY
5872 || ecs
->event_thread
->stop_requested
5874 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
5880 /* Notify observers the signal has "handle print" set. Note we
5881 returned early above if stopping; normal_stop handles the
5882 printing in that case. */
5883 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
5885 /* The signal table tells us to print about this signal. */
5886 target_terminal::ours_for_output ();
5887 gdb::observers::signal_received
.notify (ecs
->event_thread
->suspend
.stop_signal
);
5888 target_terminal::inferior ();
5891 /* Clear the signal if it should not be passed. */
5892 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
5893 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5895 if (ecs
->event_thread
->prev_pc
== ecs
->event_thread
->suspend
.stop_pc
5896 && ecs
->event_thread
->control
.trap_expected
5897 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
5899 /* We were just starting a new sequence, attempting to
5900 single-step off of a breakpoint and expecting a SIGTRAP.
5901 Instead this signal arrives. This signal will take us out
5902 of the stepping range so GDB needs to remember to, when
5903 the signal handler returns, resume stepping off that
5905 /* To simplify things, "continue" is forced to use the same
5906 code paths as single-step - set a breakpoint at the
5907 signal return address and then, once hit, step off that
5910 fprintf_unfiltered (gdb_stdlog
,
5911 "infrun: signal arrived while stepping over "
5914 insert_hp_step_resume_breakpoint_at_frame (frame
);
5915 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
5916 /* Reset trap_expected to ensure breakpoints are re-inserted. */
5917 ecs
->event_thread
->control
.trap_expected
= 0;
5919 /* If we were nexting/stepping some other thread, switch to
5920 it, so that we don't continue it, losing control. */
5921 if (!switch_back_to_stepped_thread (ecs
))
5926 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
5927 && (pc_in_thread_step_range (ecs
->event_thread
->suspend
.stop_pc
,
5929 || ecs
->event_thread
->control
.step_range_end
== 1)
5930 && frame_id_eq (get_stack_frame_id (frame
),
5931 ecs
->event_thread
->control
.step_stack_frame_id
)
5932 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
5934 /* The inferior is about to take a signal that will take it
5935 out of the single step range. Set a breakpoint at the
5936 current PC (which is presumably where the signal handler
5937 will eventually return) and then allow the inferior to
5940 Note that this is only needed for a signal delivered
5941 while in the single-step range. Nested signals aren't a
5942 problem as they eventually all return. */
5944 fprintf_unfiltered (gdb_stdlog
,
5945 "infrun: signal may take us out of "
5946 "single-step range\n");
5948 clear_step_over_info ();
5949 insert_hp_step_resume_breakpoint_at_frame (frame
);
5950 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
5951 /* Reset trap_expected to ensure breakpoints are re-inserted. */
5952 ecs
->event_thread
->control
.trap_expected
= 0;
5957 /* Note: step_resume_breakpoint may be non-NULL. This occures
5958 when either there's a nested signal, or when there's a
5959 pending signal enabled just as the signal handler returns
5960 (leaving the inferior at the step-resume-breakpoint without
5961 actually executing it). Either way continue until the
5962 breakpoint is really hit. */
5964 if (!switch_back_to_stepped_thread (ecs
))
5967 fprintf_unfiltered (gdb_stdlog
,
5968 "infrun: random signal, keep going\n");
5975 process_event_stop_test (ecs
);
5978 /* Come here when we've got some debug event / signal we can explain
5979 (IOW, not a random signal), and test whether it should cause a
5980 stop, or whether we should resume the inferior (transparently).
5981 E.g., could be a breakpoint whose condition evaluates false; we
5982 could be still stepping within the line; etc. */
5985 process_event_stop_test (struct execution_control_state
*ecs
)
5987 struct symtab_and_line stop_pc_sal
;
5988 struct frame_info
*frame
;
5989 struct gdbarch
*gdbarch
;
5990 CORE_ADDR jmp_buf_pc
;
5991 struct bpstat_what what
;
5993 /* Handle cases caused by hitting a breakpoint. */
5995 frame
= get_current_frame ();
5996 gdbarch
= get_frame_arch (frame
);
5998 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
6000 if (what
.call_dummy
)
6002 stop_stack_dummy
= what
.call_dummy
;
6005 /* A few breakpoint types have callbacks associated (e.g.,
6006 bp_jit_event). Run them now. */
6007 bpstat_run_callbacks (ecs
->event_thread
->control
.stop_bpstat
);
6009 /* If we hit an internal event that triggers symbol changes, the
6010 current frame will be invalidated within bpstat_what (e.g., if we
6011 hit an internal solib event). Re-fetch it. */
6012 frame
= get_current_frame ();
6013 gdbarch
= get_frame_arch (frame
);
6015 switch (what
.main_action
)
6017 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
6018 /* If we hit the breakpoint at longjmp while stepping, we
6019 install a momentary breakpoint at the target of the
6023 fprintf_unfiltered (gdb_stdlog
,
6024 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
6026 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6028 if (what
.is_longjmp
)
6030 struct value
*arg_value
;
6032 /* If we set the longjmp breakpoint via a SystemTap probe,
6033 then use it to extract the arguments. The destination PC
6034 is the third argument to the probe. */
6035 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
6038 jmp_buf_pc
= value_as_address (arg_value
);
6039 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
6041 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
6042 || !gdbarch_get_longjmp_target (gdbarch
,
6043 frame
, &jmp_buf_pc
))
6046 fprintf_unfiltered (gdb_stdlog
,
6047 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
6048 "(!gdbarch_get_longjmp_target)\n");
6053 /* Insert a breakpoint at resume address. */
6054 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
6057 check_exception_resume (ecs
, frame
);
6061 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
6063 struct frame_info
*init_frame
;
6065 /* There are several cases to consider.
6067 1. The initiating frame no longer exists. In this case we
6068 must stop, because the exception or longjmp has gone too
6071 2. The initiating frame exists, and is the same as the
6072 current frame. We stop, because the exception or longjmp
6075 3. The initiating frame exists and is different from the
6076 current frame. This means the exception or longjmp has
6077 been caught beneath the initiating frame, so keep going.
6079 4. longjmp breakpoint has been placed just to protect
6080 against stale dummy frames and user is not interested in
6081 stopping around longjmps. */
6084 fprintf_unfiltered (gdb_stdlog
,
6085 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
6087 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
6089 delete_exception_resume_breakpoint (ecs
->event_thread
);
6091 if (what
.is_longjmp
)
6093 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
6095 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
6103 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
6107 struct frame_id current_id
6108 = get_frame_id (get_current_frame ());
6109 if (frame_id_eq (current_id
,
6110 ecs
->event_thread
->initiating_frame
))
6112 /* Case 2. Fall through. */
6122 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6124 delete_step_resume_breakpoint (ecs
->event_thread
);
6126 end_stepping_range (ecs
);
6130 case BPSTAT_WHAT_SINGLE
:
6132 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
6133 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6134 /* Still need to check other stuff, at least the case where we
6135 are stepping and step out of the right range. */
6138 case BPSTAT_WHAT_STEP_RESUME
:
6140 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
6142 delete_step_resume_breakpoint (ecs
->event_thread
);
6143 if (ecs
->event_thread
->control
.proceed_to_finish
6144 && execution_direction
== EXEC_REVERSE
)
6146 struct thread_info
*tp
= ecs
->event_thread
;
6148 /* We are finishing a function in reverse, and just hit the
6149 step-resume breakpoint at the start address of the
6150 function, and we're almost there -- just need to back up
6151 by one more single-step, which should take us back to the
6153 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
6157 fill_in_stop_func (gdbarch
, ecs
);
6158 if (ecs
->event_thread
->suspend
.stop_pc
== ecs
->stop_func_start
6159 && execution_direction
== EXEC_REVERSE
)
6161 /* We are stepping over a function call in reverse, and just
6162 hit the step-resume breakpoint at the start address of
6163 the function. Go back to single-stepping, which should
6164 take us back to the function call. */
6165 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6171 case BPSTAT_WHAT_STOP_NOISY
:
6173 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
6174 stop_print_frame
= 1;
6176 /* Assume the thread stopped for a breapoint. We'll still check
6177 whether a/the breakpoint is there when the thread is next
6179 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6184 case BPSTAT_WHAT_STOP_SILENT
:
6186 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
6187 stop_print_frame
= 0;
6189 /* Assume the thread stopped for a breapoint. We'll still check
6190 whether a/the breakpoint is there when the thread is next
6192 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6196 case BPSTAT_WHAT_HP_STEP_RESUME
:
6198 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
6200 delete_step_resume_breakpoint (ecs
->event_thread
);
6201 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
6203 /* Back when the step-resume breakpoint was inserted, we
6204 were trying to single-step off a breakpoint. Go back to
6206 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6207 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6213 case BPSTAT_WHAT_KEEP_CHECKING
:
6217 /* If we stepped a permanent breakpoint and we had a high priority
6218 step-resume breakpoint for the address we stepped, but we didn't
6219 hit it, then we must have stepped into the signal handler. The
6220 step-resume was only necessary to catch the case of _not_
6221 stepping into the handler, so delete it, and fall through to
6222 checking whether the step finished. */
6223 if (ecs
->event_thread
->stepped_breakpoint
)
6225 struct breakpoint
*sr_bp
6226 = ecs
->event_thread
->control
.step_resume_breakpoint
;
6229 && sr_bp
->loc
->permanent
6230 && sr_bp
->type
== bp_hp_step_resume
6231 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
6234 fprintf_unfiltered (gdb_stdlog
,
6235 "infrun: stepped permanent breakpoint, stopped in "
6237 delete_step_resume_breakpoint (ecs
->event_thread
);
6238 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6242 /* We come here if we hit a breakpoint but should not stop for it.
6243 Possibly we also were stepping and should stop for that. So fall
6244 through and test for stepping. But, if not stepping, do not
6247 /* In all-stop mode, if we're currently stepping but have stopped in
6248 some other thread, we need to switch back to the stepped thread. */
6249 if (switch_back_to_stepped_thread (ecs
))
6252 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
6255 fprintf_unfiltered (gdb_stdlog
,
6256 "infrun: step-resume breakpoint is inserted\n");
6258 /* Having a step-resume breakpoint overrides anything
6259 else having to do with stepping commands until
6260 that breakpoint is reached. */
6265 if (ecs
->event_thread
->control
.step_range_end
== 0)
6268 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
6269 /* Likewise if we aren't even stepping. */
6274 /* Re-fetch current thread's frame in case the code above caused
6275 the frame cache to be re-initialized, making our FRAME variable
6276 a dangling pointer. */
6277 frame
= get_current_frame ();
6278 gdbarch
= get_frame_arch (frame
);
6279 fill_in_stop_func (gdbarch
, ecs
);
6281 /* If stepping through a line, keep going if still within it.
6283 Note that step_range_end is the address of the first instruction
6284 beyond the step range, and NOT the address of the last instruction
6287 Note also that during reverse execution, we may be stepping
6288 through a function epilogue and therefore must detect when
6289 the current-frame changes in the middle of a line. */
6291 if (pc_in_thread_step_range (ecs
->event_thread
->suspend
.stop_pc
,
6293 && (execution_direction
!= EXEC_REVERSE
6294 || frame_id_eq (get_frame_id (frame
),
6295 ecs
->event_thread
->control
.step_frame_id
)))
6299 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
6300 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
6301 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
6303 /* Tentatively re-enable range stepping; `resume' disables it if
6304 necessary (e.g., if we're stepping over a breakpoint or we
6305 have software watchpoints). */
6306 ecs
->event_thread
->control
.may_range_step
= 1;
6308 /* When stepping backward, stop at beginning of line range
6309 (unless it's the function entry point, in which case
6310 keep going back to the call point). */
6311 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6312 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
6313 && stop_pc
!= ecs
->stop_func_start
6314 && execution_direction
== EXEC_REVERSE
)
6315 end_stepping_range (ecs
);
6322 /* We stepped out of the stepping range. */
6324 /* If we are stepping at the source level and entered the runtime
6325 loader dynamic symbol resolution code...
6327 EXEC_FORWARD: we keep on single stepping until we exit the run
6328 time loader code and reach the callee's address.
6330 EXEC_REVERSE: we've already executed the callee (backward), and
6331 the runtime loader code is handled just like any other
6332 undebuggable function call. Now we need only keep stepping
6333 backward through the trampoline code, and that's handled further
6334 down, so there is nothing for us to do here. */
6336 if (execution_direction
!= EXEC_REVERSE
6337 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6338 && in_solib_dynsym_resolve_code (ecs
->event_thread
->suspend
.stop_pc
))
6340 CORE_ADDR pc_after_resolver
=
6341 gdbarch_skip_solib_resolver (gdbarch
,
6342 ecs
->event_thread
->suspend
.stop_pc
);
6345 fprintf_unfiltered (gdb_stdlog
,
6346 "infrun: stepped into dynsym resolve code\n");
6348 if (pc_after_resolver
)
6350 /* Set up a step-resume breakpoint at the address
6351 indicated by SKIP_SOLIB_RESOLVER. */
6352 symtab_and_line sr_sal
;
6353 sr_sal
.pc
= pc_after_resolver
;
6354 sr_sal
.pspace
= get_frame_program_space (frame
);
6356 insert_step_resume_breakpoint_at_sal (gdbarch
,
6357 sr_sal
, null_frame_id
);
6364 /* Step through an indirect branch thunk. */
6365 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6366 && gdbarch_in_indirect_branch_thunk (gdbarch
,
6367 ecs
->event_thread
->suspend
.stop_pc
))
6370 fprintf_unfiltered (gdb_stdlog
,
6371 "infrun: stepped into indirect branch thunk\n");
6376 if (ecs
->event_thread
->control
.step_range_end
!= 1
6377 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6378 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6379 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
6382 fprintf_unfiltered (gdb_stdlog
,
6383 "infrun: stepped into signal trampoline\n");
6384 /* The inferior, while doing a "step" or "next", has ended up in
6385 a signal trampoline (either by a signal being delivered or by
6386 the signal handler returning). Just single-step until the
6387 inferior leaves the trampoline (either by calling the handler
6393 /* If we're in the return path from a shared library trampoline,
6394 we want to proceed through the trampoline when stepping. */
6395 /* macro/2012-04-25: This needs to come before the subroutine
6396 call check below as on some targets return trampolines look
6397 like subroutine calls (MIPS16 return thunks). */
6398 if (gdbarch_in_solib_return_trampoline (gdbarch
,
6399 ecs
->event_thread
->suspend
.stop_pc
,
6400 ecs
->stop_func_name
)
6401 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6403 /* Determine where this trampoline returns. */
6404 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6405 CORE_ADDR real_stop_pc
6406 = gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6409 fprintf_unfiltered (gdb_stdlog
,
6410 "infrun: stepped into solib return tramp\n");
6412 /* Only proceed through if we know where it's going. */
6415 /* And put the step-breakpoint there and go until there. */
6416 symtab_and_line sr_sal
;
6417 sr_sal
.pc
= real_stop_pc
;
6418 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6419 sr_sal
.pspace
= get_frame_program_space (frame
);
6421 /* Do not specify what the fp should be when we stop since
6422 on some machines the prologue is where the new fp value
6424 insert_step_resume_breakpoint_at_sal (gdbarch
,
6425 sr_sal
, null_frame_id
);
6427 /* Restart without fiddling with the step ranges or
6434 /* Check for subroutine calls. The check for the current frame
6435 equalling the step ID is not necessary - the check of the
6436 previous frame's ID is sufficient - but it is a common case and
6437 cheaper than checking the previous frame's ID.
6439 NOTE: frame_id_eq will never report two invalid frame IDs as
6440 being equal, so to get into this block, both the current and
6441 previous frame must have valid frame IDs. */
6442 /* The outer_frame_id check is a heuristic to detect stepping
6443 through startup code. If we step over an instruction which
6444 sets the stack pointer from an invalid value to a valid value,
6445 we may detect that as a subroutine call from the mythical
6446 "outermost" function. This could be fixed by marking
6447 outermost frames as !stack_p,code_p,special_p. Then the
6448 initial outermost frame, before sp was valid, would
6449 have code_addr == &_start. See the comment in frame_id_eq
6451 if (!frame_id_eq (get_stack_frame_id (frame
),
6452 ecs
->event_thread
->control
.step_stack_frame_id
)
6453 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6454 ecs
->event_thread
->control
.step_stack_frame_id
)
6455 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
6457 || (ecs
->event_thread
->control
.step_start_function
6458 != find_pc_function (ecs
->event_thread
->suspend
.stop_pc
)))))
6460 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6461 CORE_ADDR real_stop_pc
;
6464 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
6466 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
6468 /* I presume that step_over_calls is only 0 when we're
6469 supposed to be stepping at the assembly language level
6470 ("stepi"). Just stop. */
6471 /* And this works the same backward as frontward. MVS */
6472 end_stepping_range (ecs
);
6476 /* Reverse stepping through solib trampolines. */
6478 if (execution_direction
== EXEC_REVERSE
6479 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6480 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6481 || (ecs
->stop_func_start
== 0
6482 && in_solib_dynsym_resolve_code (stop_pc
))))
6484 /* Any solib trampoline code can be handled in reverse
6485 by simply continuing to single-step. We have already
6486 executed the solib function (backwards), and a few
6487 steps will take us back through the trampoline to the
6493 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6495 /* We're doing a "next".
6497 Normal (forward) execution: set a breakpoint at the
6498 callee's return address (the address at which the caller
6501 Reverse (backward) execution. set the step-resume
6502 breakpoint at the start of the function that we just
6503 stepped into (backwards), and continue to there. When we
6504 get there, we'll need to single-step back to the caller. */
6506 if (execution_direction
== EXEC_REVERSE
)
6508 /* If we're already at the start of the function, we've either
6509 just stepped backward into a single instruction function,
6510 or stepped back out of a signal handler to the first instruction
6511 of the function. Just keep going, which will single-step back
6513 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
6515 /* Normal function call return (static or dynamic). */
6516 symtab_and_line sr_sal
;
6517 sr_sal
.pc
= ecs
->stop_func_start
;
6518 sr_sal
.pspace
= get_frame_program_space (frame
);
6519 insert_step_resume_breakpoint_at_sal (gdbarch
,
6520 sr_sal
, null_frame_id
);
6524 insert_step_resume_breakpoint_at_caller (frame
);
6530 /* If we are in a function call trampoline (a stub between the
6531 calling routine and the real function), locate the real
6532 function. That's what tells us (a) whether we want to step
6533 into it at all, and (b) what prologue we want to run to the
6534 end of, if we do step into it. */
6535 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
6536 if (real_stop_pc
== 0)
6537 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6538 if (real_stop_pc
!= 0)
6539 ecs
->stop_func_start
= real_stop_pc
;
6541 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
6543 symtab_and_line sr_sal
;
6544 sr_sal
.pc
= ecs
->stop_func_start
;
6545 sr_sal
.pspace
= get_frame_program_space (frame
);
6547 insert_step_resume_breakpoint_at_sal (gdbarch
,
6548 sr_sal
, null_frame_id
);
6553 /* If we have line number information for the function we are
6554 thinking of stepping into and the function isn't on the skip
6557 If there are several symtabs at that PC (e.g. with include
6558 files), just want to know whether *any* of them have line
6559 numbers. find_pc_line handles this. */
6561 struct symtab_and_line tmp_sal
;
6563 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
6564 if (tmp_sal
.line
!= 0
6565 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
6568 if (execution_direction
== EXEC_REVERSE
)
6569 handle_step_into_function_backward (gdbarch
, ecs
);
6571 handle_step_into_function (gdbarch
, ecs
);
6576 /* If we have no line number and the step-stop-if-no-debug is
6577 set, we stop the step so that the user has a chance to switch
6578 in assembly mode. */
6579 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6580 && step_stop_if_no_debug
)
6582 end_stepping_range (ecs
);
6586 if (execution_direction
== EXEC_REVERSE
)
6588 /* If we're already at the start of the function, we've either just
6589 stepped backward into a single instruction function without line
6590 number info, or stepped back out of a signal handler to the first
6591 instruction of the function without line number info. Just keep
6592 going, which will single-step back to the caller. */
6593 if (ecs
->stop_func_start
!= stop_pc
)
6595 /* Set a breakpoint at callee's start address.
6596 From there we can step once and be back in the caller. */
6597 symtab_and_line sr_sal
;
6598 sr_sal
.pc
= ecs
->stop_func_start
;
6599 sr_sal
.pspace
= get_frame_program_space (frame
);
6600 insert_step_resume_breakpoint_at_sal (gdbarch
,
6601 sr_sal
, null_frame_id
);
6605 /* Set a breakpoint at callee's return address (the address
6606 at which the caller will resume). */
6607 insert_step_resume_breakpoint_at_caller (frame
);
6613 /* Reverse stepping through solib trampolines. */
6615 if (execution_direction
== EXEC_REVERSE
6616 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6618 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6620 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6621 || (ecs
->stop_func_start
== 0
6622 && in_solib_dynsym_resolve_code (stop_pc
)))
6624 /* Any solib trampoline code can be handled in reverse
6625 by simply continuing to single-step. We have already
6626 executed the solib function (backwards), and a few
6627 steps will take us back through the trampoline to the
6632 else if (in_solib_dynsym_resolve_code (stop_pc
))
6634 /* Stepped backward into the solib dynsym resolver.
6635 Set a breakpoint at its start and continue, then
6636 one more step will take us out. */
6637 symtab_and_line sr_sal
;
6638 sr_sal
.pc
= ecs
->stop_func_start
;
6639 sr_sal
.pspace
= get_frame_program_space (frame
);
6640 insert_step_resume_breakpoint_at_sal (gdbarch
,
6641 sr_sal
, null_frame_id
);
6647 stop_pc_sal
= find_pc_line (ecs
->event_thread
->suspend
.stop_pc
, 0);
6649 /* NOTE: tausq/2004-05-24: This if block used to be done before all
6650 the trampoline processing logic, however, there are some trampolines
6651 that have no names, so we should do trampoline handling first. */
6652 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6653 && ecs
->stop_func_name
== NULL
6654 && stop_pc_sal
.line
== 0)
6657 fprintf_unfiltered (gdb_stdlog
,
6658 "infrun: stepped into undebuggable function\n");
6660 /* The inferior just stepped into, or returned to, an
6661 undebuggable function (where there is no debugging information
6662 and no line number corresponding to the address where the
6663 inferior stopped). Since we want to skip this kind of code,
6664 we keep going until the inferior returns from this
6665 function - unless the user has asked us not to (via
6666 set step-mode) or we no longer know how to get back
6667 to the call site. */
6668 if (step_stop_if_no_debug
6669 || !frame_id_p (frame_unwind_caller_id (frame
)))
6671 /* If we have no line number and the step-stop-if-no-debug
6672 is set, we stop the step so that the user has a chance to
6673 switch in assembly mode. */
6674 end_stepping_range (ecs
);
6679 /* Set a breakpoint at callee's return address (the address
6680 at which the caller will resume). */
6681 insert_step_resume_breakpoint_at_caller (frame
);
6687 if (ecs
->event_thread
->control
.step_range_end
== 1)
6689 /* It is stepi or nexti. We always want to stop stepping after
6692 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
6693 end_stepping_range (ecs
);
6697 if (stop_pc_sal
.line
== 0)
6699 /* We have no line number information. That means to stop
6700 stepping (does this always happen right after one instruction,
6701 when we do "s" in a function with no line numbers,
6702 or can this happen as a result of a return or longjmp?). */
6704 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
6705 end_stepping_range (ecs
);
6709 /* Look for "calls" to inlined functions, part one. If the inline
6710 frame machinery detected some skipped call sites, we have entered
6711 a new inline function. */
6713 if (frame_id_eq (get_frame_id (get_current_frame ()),
6714 ecs
->event_thread
->control
.step_frame_id
)
6715 && inline_skipped_frames (ecs
->event_thread
))
6718 fprintf_unfiltered (gdb_stdlog
,
6719 "infrun: stepped into inlined function\n");
6721 symtab_and_line call_sal
= find_frame_sal (get_current_frame ());
6723 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
6725 /* For "step", we're going to stop. But if the call site
6726 for this inlined function is on the same source line as
6727 we were previously stepping, go down into the function
6728 first. Otherwise stop at the call site. */
6730 if (call_sal
.line
== ecs
->event_thread
->current_line
6731 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6732 step_into_inline_frame (ecs
->event_thread
);
6734 end_stepping_range (ecs
);
6739 /* For "next", we should stop at the call site if it is on a
6740 different source line. Otherwise continue through the
6741 inlined function. */
6742 if (call_sal
.line
== ecs
->event_thread
->current_line
6743 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6746 end_stepping_range (ecs
);
6751 /* Look for "calls" to inlined functions, part two. If we are still
6752 in the same real function we were stepping through, but we have
6753 to go further up to find the exact frame ID, we are stepping
6754 through a more inlined call beyond its call site. */
6756 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
6757 && !frame_id_eq (get_frame_id (get_current_frame ()),
6758 ecs
->event_thread
->control
.step_frame_id
)
6759 && stepped_in_from (get_current_frame (),
6760 ecs
->event_thread
->control
.step_frame_id
))
6763 fprintf_unfiltered (gdb_stdlog
,
6764 "infrun: stepping through inlined function\n");
6766 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6769 end_stepping_range (ecs
);
6773 if ((ecs
->event_thread
->suspend
.stop_pc
== stop_pc_sal
.pc
)
6774 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
6775 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
6777 /* We are at the start of a different line. So stop. Note that
6778 we don't stop if we step into the middle of a different line.
6779 That is said to make things like for (;;) statements work
6782 fprintf_unfiltered (gdb_stdlog
,
6783 "infrun: stepped to a different line\n");
6784 end_stepping_range (ecs
);
6788 /* We aren't done stepping.
6790 Optimize by setting the stepping range to the line.
6791 (We might not be in the original line, but if we entered a
6792 new line in mid-statement, we continue stepping. This makes
6793 things like for(;;) statements work better.) */
6795 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
6796 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
6797 ecs
->event_thread
->control
.may_range_step
= 1;
6798 set_step_info (frame
, stop_pc_sal
);
6801 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
6805 /* In all-stop mode, if we're currently stepping but have stopped in
6806 some other thread, we may need to switch back to the stepped
6807 thread. Returns true we set the inferior running, false if we left
6808 it stopped (and the event needs further processing). */
6811 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
6813 if (!target_is_non_stop_p ())
6815 struct thread_info
*stepping_thread
;
6817 /* If any thread is blocked on some internal breakpoint, and we
6818 simply need to step over that breakpoint to get it going
6819 again, do that first. */
6821 /* However, if we see an event for the stepping thread, then we
6822 know all other threads have been moved past their breakpoints
6823 already. Let the caller check whether the step is finished,
6824 etc., before deciding to move it past a breakpoint. */
6825 if (ecs
->event_thread
->control
.step_range_end
!= 0)
6828 /* Check if the current thread is blocked on an incomplete
6829 step-over, interrupted by a random signal. */
6830 if (ecs
->event_thread
->control
.trap_expected
6831 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
6835 fprintf_unfiltered (gdb_stdlog
,
6836 "infrun: need to finish step-over of [%s]\n",
6837 target_pid_to_str (ecs
->event_thread
->ptid
).c_str ());
6843 /* Check if the current thread is blocked by a single-step
6844 breakpoint of another thread. */
6845 if (ecs
->hit_singlestep_breakpoint
)
6849 fprintf_unfiltered (gdb_stdlog
,
6850 "infrun: need to step [%s] over single-step "
6852 target_pid_to_str (ecs
->ptid
).c_str ());
6858 /* If this thread needs yet another step-over (e.g., stepping
6859 through a delay slot), do it first before moving on to
6861 if (thread_still_needs_step_over (ecs
->event_thread
))
6865 fprintf_unfiltered (gdb_stdlog
,
6866 "infrun: thread [%s] still needs step-over\n",
6867 target_pid_to_str (ecs
->event_thread
->ptid
).c_str ());
6873 /* If scheduler locking applies even if not stepping, there's no
6874 need to walk over threads. Above we've checked whether the
6875 current thread is stepping. If some other thread not the
6876 event thread is stepping, then it must be that scheduler
6877 locking is not in effect. */
6878 if (schedlock_applies (ecs
->event_thread
))
6881 /* Otherwise, we no longer expect a trap in the current thread.
6882 Clear the trap_expected flag before switching back -- this is
6883 what keep_going does as well, if we call it. */
6884 ecs
->event_thread
->control
.trap_expected
= 0;
6886 /* Likewise, clear the signal if it should not be passed. */
6887 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
6888 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6890 /* Do all pending step-overs before actually proceeding with
6892 if (start_step_over ())
6894 prepare_to_wait (ecs
);
6898 /* Look for the stepping/nexting thread. */
6899 stepping_thread
= NULL
;
6901 for (thread_info
*tp
: all_non_exited_threads ())
6903 /* Ignore threads of processes the caller is not
6906 && tp
->ptid
.pid () != ecs
->ptid
.pid ())
6909 /* When stepping over a breakpoint, we lock all threads
6910 except the one that needs to move past the breakpoint.
6911 If a non-event thread has this set, the "incomplete
6912 step-over" check above should have caught it earlier. */
6913 if (tp
->control
.trap_expected
)
6915 internal_error (__FILE__
, __LINE__
,
6916 "[%s] has inconsistent state: "
6917 "trap_expected=%d\n",
6918 target_pid_to_str (tp
->ptid
).c_str (),
6919 tp
->control
.trap_expected
);
6922 /* Did we find the stepping thread? */
6923 if (tp
->control
.step_range_end
)
6925 /* Yep. There should only one though. */
6926 gdb_assert (stepping_thread
== NULL
);
6928 /* The event thread is handled at the top, before we
6930 gdb_assert (tp
!= ecs
->event_thread
);
6932 /* If some thread other than the event thread is
6933 stepping, then scheduler locking can't be in effect,
6934 otherwise we wouldn't have resumed the current event
6935 thread in the first place. */
6936 gdb_assert (!schedlock_applies (tp
));
6938 stepping_thread
= tp
;
6942 if (stepping_thread
!= NULL
)
6945 fprintf_unfiltered (gdb_stdlog
,
6946 "infrun: switching back to stepped thread\n");
6948 if (keep_going_stepped_thread (stepping_thread
))
6950 prepare_to_wait (ecs
);
6959 /* Set a previously stepped thread back to stepping. Returns true on
6960 success, false if the resume is not possible (e.g., the thread
6964 keep_going_stepped_thread (struct thread_info
*tp
)
6966 struct frame_info
*frame
;
6967 struct execution_control_state ecss
;
6968 struct execution_control_state
*ecs
= &ecss
;
6970 /* If the stepping thread exited, then don't try to switch back and
6971 resume it, which could fail in several different ways depending
6972 on the target. Instead, just keep going.
6974 We can find a stepping dead thread in the thread list in two
6977 - The target supports thread exit events, and when the target
6978 tries to delete the thread from the thread list, inferior_ptid
6979 pointed at the exiting thread. In such case, calling
6980 delete_thread does not really remove the thread from the list;
6981 instead, the thread is left listed, with 'exited' state.
6983 - The target's debug interface does not support thread exit
6984 events, and so we have no idea whatsoever if the previously
6985 stepping thread is still alive. For that reason, we need to
6986 synchronously query the target now. */
6988 if (tp
->state
== THREAD_EXITED
|| !target_thread_alive (tp
->ptid
))
6991 fprintf_unfiltered (gdb_stdlog
,
6992 "infrun: not resuming previously "
6993 "stepped thread, it has vanished\n");
7000 fprintf_unfiltered (gdb_stdlog
,
7001 "infrun: resuming previously stepped thread\n");
7003 reset_ecs (ecs
, tp
);
7004 switch_to_thread (tp
);
7006 tp
->suspend
.stop_pc
= regcache_read_pc (get_thread_regcache (tp
));
7007 frame
= get_current_frame ();
7009 /* If the PC of the thread we were trying to single-step has
7010 changed, then that thread has trapped or been signaled, but the
7011 event has not been reported to GDB yet. Re-poll the target
7012 looking for this particular thread's event (i.e. temporarily
7013 enable schedlock) by:
7015 - setting a break at the current PC
7016 - resuming that particular thread, only (by setting trap
7019 This prevents us continuously moving the single-step breakpoint
7020 forward, one instruction at a time, overstepping. */
7022 if (tp
->suspend
.stop_pc
!= tp
->prev_pc
)
7027 fprintf_unfiltered (gdb_stdlog
,
7028 "infrun: expected thread advanced also (%s -> %s)\n",
7029 paddress (target_gdbarch (), tp
->prev_pc
),
7030 paddress (target_gdbarch (), tp
->suspend
.stop_pc
));
7032 /* Clear the info of the previous step-over, as it's no longer
7033 valid (if the thread was trying to step over a breakpoint, it
7034 has already succeeded). It's what keep_going would do too,
7035 if we called it. Do this before trying to insert the sss
7036 breakpoint, otherwise if we were previously trying to step
7037 over this exact address in another thread, the breakpoint is
7039 clear_step_over_info ();
7040 tp
->control
.trap_expected
= 0;
7042 insert_single_step_breakpoint (get_frame_arch (frame
),
7043 get_frame_address_space (frame
),
7044 tp
->suspend
.stop_pc
);
7047 resume_ptid
= internal_resume_ptid (tp
->control
.stepping_command
);
7048 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
7053 fprintf_unfiltered (gdb_stdlog
,
7054 "infrun: expected thread still hasn't advanced\n");
7056 keep_going_pass_signal (ecs
);
7061 /* Is thread TP in the middle of (software or hardware)
7062 single-stepping? (Note the result of this function must never be
7063 passed directly as target_resume's STEP parameter.) */
7066 currently_stepping (struct thread_info
*tp
)
7068 return ((tp
->control
.step_range_end
7069 && tp
->control
.step_resume_breakpoint
== NULL
)
7070 || tp
->control
.trap_expected
7071 || tp
->stepped_breakpoint
7072 || bpstat_should_step ());
7075 /* Inferior has stepped into a subroutine call with source code that
7076 we should not step over. Do step to the first line of code in
7080 handle_step_into_function (struct gdbarch
*gdbarch
,
7081 struct execution_control_state
*ecs
)
7083 fill_in_stop_func (gdbarch
, ecs
);
7085 compunit_symtab
*cust
7086 = find_pc_compunit_symtab (ecs
->event_thread
->suspend
.stop_pc
);
7087 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7088 ecs
->stop_func_start
7089 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7091 symtab_and_line stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7092 /* Use the step_resume_break to step until the end of the prologue,
7093 even if that involves jumps (as it seems to on the vax under
7095 /* If the prologue ends in the middle of a source line, continue to
7096 the end of that source line (if it is still within the function).
7097 Otherwise, just go to end of prologue. */
7098 if (stop_func_sal
.end
7099 && stop_func_sal
.pc
!= ecs
->stop_func_start
7100 && stop_func_sal
.end
< ecs
->stop_func_end
)
7101 ecs
->stop_func_start
= stop_func_sal
.end
;
7103 /* Architectures which require breakpoint adjustment might not be able
7104 to place a breakpoint at the computed address. If so, the test
7105 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7106 ecs->stop_func_start to an address at which a breakpoint may be
7107 legitimately placed.
7109 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7110 made, GDB will enter an infinite loop when stepping through
7111 optimized code consisting of VLIW instructions which contain
7112 subinstructions corresponding to different source lines. On
7113 FR-V, it's not permitted to place a breakpoint on any but the
7114 first subinstruction of a VLIW instruction. When a breakpoint is
7115 set, GDB will adjust the breakpoint address to the beginning of
7116 the VLIW instruction. Thus, we need to make the corresponding
7117 adjustment here when computing the stop address. */
7119 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
7121 ecs
->stop_func_start
7122 = gdbarch_adjust_breakpoint_address (gdbarch
,
7123 ecs
->stop_func_start
);
7126 if (ecs
->stop_func_start
== ecs
->event_thread
->suspend
.stop_pc
)
7128 /* We are already there: stop now. */
7129 end_stepping_range (ecs
);
7134 /* Put the step-breakpoint there and go until there. */
7135 symtab_and_line sr_sal
;
7136 sr_sal
.pc
= ecs
->stop_func_start
;
7137 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
7138 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
7140 /* Do not specify what the fp should be when we stop since on
7141 some machines the prologue is where the new fp value is
7143 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
7145 /* And make sure stepping stops right away then. */
7146 ecs
->event_thread
->control
.step_range_end
7147 = ecs
->event_thread
->control
.step_range_start
;
7152 /* Inferior has stepped backward into a subroutine call with source
7153 code that we should not step over. Do step to the beginning of the
7154 last line of code in it. */
7157 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
7158 struct execution_control_state
*ecs
)
7160 struct compunit_symtab
*cust
;
7161 struct symtab_and_line stop_func_sal
;
7163 fill_in_stop_func (gdbarch
, ecs
);
7165 cust
= find_pc_compunit_symtab (ecs
->event_thread
->suspend
.stop_pc
);
7166 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7167 ecs
->stop_func_start
7168 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7170 stop_func_sal
= find_pc_line (ecs
->event_thread
->suspend
.stop_pc
, 0);
7172 /* OK, we're just going to keep stepping here. */
7173 if (stop_func_sal
.pc
== ecs
->event_thread
->suspend
.stop_pc
)
7175 /* We're there already. Just stop stepping now. */
7176 end_stepping_range (ecs
);
7180 /* Else just reset the step range and keep going.
7181 No step-resume breakpoint, they don't work for
7182 epilogues, which can have multiple entry paths. */
7183 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
7184 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
7190 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7191 This is used to both functions and to skip over code. */
7194 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
7195 struct symtab_and_line sr_sal
,
7196 struct frame_id sr_id
,
7197 enum bptype sr_type
)
7199 /* There should never be more than one step-resume or longjmp-resume
7200 breakpoint per thread, so we should never be setting a new
7201 step_resume_breakpoint when one is already active. */
7202 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
7203 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
7206 fprintf_unfiltered (gdb_stdlog
,
7207 "infrun: inserting step-resume breakpoint at %s\n",
7208 paddress (gdbarch
, sr_sal
.pc
));
7210 inferior_thread ()->control
.step_resume_breakpoint
7211 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
).release ();
7215 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
7216 struct symtab_and_line sr_sal
,
7217 struct frame_id sr_id
)
7219 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
7224 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7225 This is used to skip a potential signal handler.
7227 This is called with the interrupted function's frame. The signal
7228 handler, when it returns, will resume the interrupted function at
7232 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
7234 gdb_assert (return_frame
!= NULL
);
7236 struct gdbarch
*gdbarch
= get_frame_arch (return_frame
);
7238 symtab_and_line sr_sal
;
7239 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
7240 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7241 sr_sal
.pspace
= get_frame_program_space (return_frame
);
7243 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
7244 get_stack_frame_id (return_frame
),
7248 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7249 is used to skip a function after stepping into it (for "next" or if
7250 the called function has no debugging information).
7252 The current function has almost always been reached by single
7253 stepping a call or return instruction. NEXT_FRAME belongs to the
7254 current function, and the breakpoint will be set at the caller's
7257 This is a separate function rather than reusing
7258 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7259 get_prev_frame, which may stop prematurely (see the implementation
7260 of frame_unwind_caller_id for an example). */
7263 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
7265 /* We shouldn't have gotten here if we don't know where the call site
7267 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
7269 struct gdbarch
*gdbarch
= frame_unwind_caller_arch (next_frame
);
7271 symtab_and_line sr_sal
;
7272 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
7273 frame_unwind_caller_pc (next_frame
));
7274 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7275 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
7277 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
7278 frame_unwind_caller_id (next_frame
));
7281 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7282 new breakpoint at the target of a jmp_buf. The handling of
7283 longjmp-resume uses the same mechanisms used for handling
7284 "step-resume" breakpoints. */
7287 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
7289 /* There should never be more than one longjmp-resume breakpoint per
7290 thread, so we should never be setting a new
7291 longjmp_resume_breakpoint when one is already active. */
7292 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
7295 fprintf_unfiltered (gdb_stdlog
,
7296 "infrun: inserting longjmp-resume breakpoint at %s\n",
7297 paddress (gdbarch
, pc
));
7299 inferior_thread ()->control
.exception_resume_breakpoint
=
7300 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
).release ();
7303 /* Insert an exception resume breakpoint. TP is the thread throwing
7304 the exception. The block B is the block of the unwinder debug hook
7305 function. FRAME is the frame corresponding to the call to this
7306 function. SYM is the symbol of the function argument holding the
7307 target PC of the exception. */
7310 insert_exception_resume_breakpoint (struct thread_info
*tp
,
7311 const struct block
*b
,
7312 struct frame_info
*frame
,
7317 struct block_symbol vsym
;
7318 struct value
*value
;
7320 struct breakpoint
*bp
;
7322 vsym
= lookup_symbol_search_name (SYMBOL_SEARCH_NAME (sym
),
7324 value
= read_var_value (vsym
.symbol
, vsym
.block
, frame
);
7325 /* If the value was optimized out, revert to the old behavior. */
7326 if (! value_optimized_out (value
))
7328 handler
= value_as_address (value
);
7331 fprintf_unfiltered (gdb_stdlog
,
7332 "infrun: exception resume at %lx\n",
7333 (unsigned long) handler
);
7335 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7337 bp_exception_resume
).release ();
7339 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7342 bp
->thread
= tp
->global_num
;
7343 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7346 CATCH (e
, RETURN_MASK_ERROR
)
7348 /* We want to ignore errors here. */
7353 /* A helper for check_exception_resume that sets an
7354 exception-breakpoint based on a SystemTap probe. */
7357 insert_exception_resume_from_probe (struct thread_info
*tp
,
7358 const struct bound_probe
*probe
,
7359 struct frame_info
*frame
)
7361 struct value
*arg_value
;
7363 struct breakpoint
*bp
;
7365 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
7369 handler
= value_as_address (arg_value
);
7372 fprintf_unfiltered (gdb_stdlog
,
7373 "infrun: exception resume at %s\n",
7374 paddress (get_objfile_arch (probe
->objfile
),
7377 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7378 handler
, bp_exception_resume
).release ();
7379 bp
->thread
= tp
->global_num
;
7380 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7383 /* This is called when an exception has been intercepted. Check to
7384 see whether the exception's destination is of interest, and if so,
7385 set an exception resume breakpoint there. */
7388 check_exception_resume (struct execution_control_state
*ecs
,
7389 struct frame_info
*frame
)
7391 struct bound_probe probe
;
7392 struct symbol
*func
;
7394 /* First see if this exception unwinding breakpoint was set via a
7395 SystemTap probe point. If so, the probe has two arguments: the
7396 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7397 set a breakpoint there. */
7398 probe
= find_probe_by_pc (get_frame_pc (frame
));
7401 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
7405 func
= get_frame_function (frame
);
7411 const struct block
*b
;
7412 struct block_iterator iter
;
7416 /* The exception breakpoint is a thread-specific breakpoint on
7417 the unwinder's debug hook, declared as:
7419 void _Unwind_DebugHook (void *cfa, void *handler);
7421 The CFA argument indicates the frame to which control is
7422 about to be transferred. HANDLER is the destination PC.
7424 We ignore the CFA and set a temporary breakpoint at HANDLER.
7425 This is not extremely efficient but it avoids issues in gdb
7426 with computing the DWARF CFA, and it also works even in weird
7427 cases such as throwing an exception from inside a signal
7430 b
= SYMBOL_BLOCK_VALUE (func
);
7431 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
7433 if (!SYMBOL_IS_ARGUMENT (sym
))
7440 insert_exception_resume_breakpoint (ecs
->event_thread
,
7446 CATCH (e
, RETURN_MASK_ERROR
)
7453 stop_waiting (struct execution_control_state
*ecs
)
7456 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
7458 /* Let callers know we don't want to wait for the inferior anymore. */
7459 ecs
->wait_some_more
= 0;
7461 /* If all-stop, but the target is always in non-stop mode, stop all
7462 threads now that we're presenting the stop to the user. */
7463 if (!non_stop
&& target_is_non_stop_p ())
7464 stop_all_threads ();
7467 /* Like keep_going, but passes the signal to the inferior, even if the
7468 signal is set to nopass. */
7471 keep_going_pass_signal (struct execution_control_state
*ecs
)
7473 gdb_assert (ecs
->event_thread
->ptid
== inferior_ptid
);
7474 gdb_assert (!ecs
->event_thread
->resumed
);
7476 /* Save the pc before execution, to compare with pc after stop. */
7477 ecs
->event_thread
->prev_pc
7478 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
7480 if (ecs
->event_thread
->control
.trap_expected
)
7482 struct thread_info
*tp
= ecs
->event_thread
;
7485 fprintf_unfiltered (gdb_stdlog
,
7486 "infrun: %s has trap_expected set, "
7487 "resuming to collect trap\n",
7488 target_pid_to_str (tp
->ptid
).c_str ());
7490 /* We haven't yet gotten our trap, and either: intercepted a
7491 non-signal event (e.g., a fork); or took a signal which we
7492 are supposed to pass through to the inferior. Simply
7494 resume (ecs
->event_thread
->suspend
.stop_signal
);
7496 else if (step_over_info_valid_p ())
7498 /* Another thread is stepping over a breakpoint in-line. If
7499 this thread needs a step-over too, queue the request. In
7500 either case, this resume must be deferred for later. */
7501 struct thread_info
*tp
= ecs
->event_thread
;
7503 if (ecs
->hit_singlestep_breakpoint
7504 || thread_still_needs_step_over (tp
))
7507 fprintf_unfiltered (gdb_stdlog
,
7508 "infrun: step-over already in progress: "
7509 "step-over for %s deferred\n",
7510 target_pid_to_str (tp
->ptid
).c_str ());
7511 thread_step_over_chain_enqueue (tp
);
7516 fprintf_unfiltered (gdb_stdlog
,
7517 "infrun: step-over in progress: "
7518 "resume of %s deferred\n",
7519 target_pid_to_str (tp
->ptid
).c_str ());
7524 struct regcache
*regcache
= get_current_regcache ();
7527 step_over_what step_what
;
7529 /* Either the trap was not expected, but we are continuing
7530 anyway (if we got a signal, the user asked it be passed to
7533 We got our expected trap, but decided we should resume from
7536 We're going to run this baby now!
7538 Note that insert_breakpoints won't try to re-insert
7539 already inserted breakpoints. Therefore, we don't
7540 care if breakpoints were already inserted, or not. */
7542 /* If we need to step over a breakpoint, and we're not using
7543 displaced stepping to do so, insert all breakpoints
7544 (watchpoints, etc.) but the one we're stepping over, step one
7545 instruction, and then re-insert the breakpoint when that step
7548 step_what
= thread_still_needs_step_over (ecs
->event_thread
);
7550 remove_bp
= (ecs
->hit_singlestep_breakpoint
7551 || (step_what
& STEP_OVER_BREAKPOINT
));
7552 remove_wps
= (step_what
& STEP_OVER_WATCHPOINT
);
7554 /* We can't use displaced stepping if we need to step past a
7555 watchpoint. The instruction copied to the scratch pad would
7556 still trigger the watchpoint. */
7558 && (remove_wps
|| !use_displaced_stepping (ecs
->event_thread
)))
7560 set_step_over_info (regcache
->aspace (),
7561 regcache_read_pc (regcache
), remove_wps
,
7562 ecs
->event_thread
->global_num
);
7564 else if (remove_wps
)
7565 set_step_over_info (NULL
, 0, remove_wps
, -1);
7567 /* If we now need to do an in-line step-over, we need to stop
7568 all other threads. Note this must be done before
7569 insert_breakpoints below, because that removes the breakpoint
7570 we're about to step over, otherwise other threads could miss
7572 if (step_over_info_valid_p () && target_is_non_stop_p ())
7573 stop_all_threads ();
7575 /* Stop stepping if inserting breakpoints fails. */
7578 insert_breakpoints ();
7580 CATCH (e
, RETURN_MASK_ERROR
)
7582 exception_print (gdb_stderr
, e
);
7584 clear_step_over_info ();
7589 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
7591 resume (ecs
->event_thread
->suspend
.stop_signal
);
7594 prepare_to_wait (ecs
);
7597 /* Called when we should continue running the inferior, because the
7598 current event doesn't cause a user visible stop. This does the
7599 resuming part; waiting for the next event is done elsewhere. */
7602 keep_going (struct execution_control_state
*ecs
)
7604 if (ecs
->event_thread
->control
.trap_expected
7605 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
7606 ecs
->event_thread
->control
.trap_expected
= 0;
7608 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7609 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7610 keep_going_pass_signal (ecs
);
7613 /* This function normally comes after a resume, before
7614 handle_inferior_event exits. It takes care of any last bits of
7615 housekeeping, and sets the all-important wait_some_more flag. */
7618 prepare_to_wait (struct execution_control_state
*ecs
)
7621 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
7623 ecs
->wait_some_more
= 1;
7625 if (!target_is_async_p ())
7626 mark_infrun_async_event_handler ();
7629 /* We are done with the step range of a step/next/si/ni command.
7630 Called once for each n of a "step n" operation. */
7633 end_stepping_range (struct execution_control_state
*ecs
)
7635 ecs
->event_thread
->control
.stop_step
= 1;
7639 /* Several print_*_reason functions to print why the inferior has stopped.
7640 We always print something when the inferior exits, or receives a signal.
7641 The rest of the cases are dealt with later on in normal_stop and
7642 print_it_typical. Ideally there should be a call to one of these
7643 print_*_reason functions functions from handle_inferior_event each time
7644 stop_waiting is called.
7646 Note that we don't call these directly, instead we delegate that to
7647 the interpreters, through observers. Interpreters then call these
7648 with whatever uiout is right. */
7651 print_end_stepping_range_reason (struct ui_out
*uiout
)
7653 /* For CLI-like interpreters, print nothing. */
7655 if (uiout
->is_mi_like_p ())
7657 uiout
->field_string ("reason",
7658 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
7663 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7665 annotate_signalled ();
7666 if (uiout
->is_mi_like_p ())
7668 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
7669 uiout
->text ("\nProgram terminated with signal ");
7670 annotate_signal_name ();
7671 uiout
->field_string ("signal-name",
7672 gdb_signal_to_name (siggnal
));
7673 annotate_signal_name_end ();
7675 annotate_signal_string ();
7676 uiout
->field_string ("signal-meaning",
7677 gdb_signal_to_string (siggnal
));
7678 annotate_signal_string_end ();
7679 uiout
->text (".\n");
7680 uiout
->text ("The program no longer exists.\n");
7684 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
7686 struct inferior
*inf
= current_inferior ();
7687 std::string pidstr
= target_pid_to_str (ptid_t (inf
->pid
));
7689 annotate_exited (exitstatus
);
7692 if (uiout
->is_mi_like_p ())
7693 uiout
->field_string ("reason", async_reason_lookup (EXEC_ASYNC_EXITED
));
7694 uiout
->text ("[Inferior ");
7695 uiout
->text (plongest (inf
->num
));
7697 uiout
->text (pidstr
.c_str ());
7698 uiout
->text (") exited with code ");
7699 uiout
->field_fmt ("exit-code", "0%o", (unsigned int) exitstatus
);
7700 uiout
->text ("]\n");
7704 if (uiout
->is_mi_like_p ())
7706 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
7707 uiout
->text ("[Inferior ");
7708 uiout
->text (plongest (inf
->num
));
7710 uiout
->text (pidstr
.c_str ());
7711 uiout
->text (") exited normally]\n");
7715 /* Some targets/architectures can do extra processing/display of
7716 segmentation faults. E.g., Intel MPX boundary faults.
7717 Call the architecture dependent function to handle the fault. */
7720 handle_segmentation_fault (struct ui_out
*uiout
)
7722 struct regcache
*regcache
= get_current_regcache ();
7723 struct gdbarch
*gdbarch
= regcache
->arch ();
7725 if (gdbarch_handle_segmentation_fault_p (gdbarch
))
7726 gdbarch_handle_segmentation_fault (gdbarch
, uiout
);
7730 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7732 struct thread_info
*thr
= inferior_thread ();
7736 if (uiout
->is_mi_like_p ())
7738 else if (show_thread_that_caused_stop ())
7742 uiout
->text ("\nThread ");
7743 uiout
->field_fmt ("thread-id", "%s", print_thread_id (thr
));
7745 name
= thr
->name
!= NULL
? thr
->name
: target_thread_name (thr
);
7748 uiout
->text (" \"");
7749 uiout
->field_fmt ("name", "%s", name
);
7754 uiout
->text ("\nProgram");
7756 if (siggnal
== GDB_SIGNAL_0
&& !uiout
->is_mi_like_p ())
7757 uiout
->text (" stopped");
7760 uiout
->text (" received signal ");
7761 annotate_signal_name ();
7762 if (uiout
->is_mi_like_p ())
7764 ("reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
7765 uiout
->field_string ("signal-name", gdb_signal_to_name (siggnal
));
7766 annotate_signal_name_end ();
7768 annotate_signal_string ();
7769 uiout
->field_string ("signal-meaning", gdb_signal_to_string (siggnal
));
7771 if (siggnal
== GDB_SIGNAL_SEGV
)
7772 handle_segmentation_fault (uiout
);
7774 annotate_signal_string_end ();
7776 uiout
->text (".\n");
7780 print_no_history_reason (struct ui_out
*uiout
)
7782 uiout
->text ("\nNo more reverse-execution history.\n");
7785 /* Print current location without a level number, if we have changed
7786 functions or hit a breakpoint. Print source line if we have one.
7787 bpstat_print contains the logic deciding in detail what to print,
7788 based on the event(s) that just occurred. */
7791 print_stop_location (struct target_waitstatus
*ws
)
7794 enum print_what source_flag
;
7795 int do_frame_printing
= 1;
7796 struct thread_info
*tp
= inferior_thread ();
7798 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
7802 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
7803 should) carry around the function and does (or should) use
7804 that when doing a frame comparison. */
7805 if (tp
->control
.stop_step
7806 && frame_id_eq (tp
->control
.step_frame_id
,
7807 get_frame_id (get_current_frame ()))
7808 && (tp
->control
.step_start_function
7809 == find_pc_function (tp
->suspend
.stop_pc
)))
7811 /* Finished step, just print source line. */
7812 source_flag
= SRC_LINE
;
7816 /* Print location and source line. */
7817 source_flag
= SRC_AND_LOC
;
7820 case PRINT_SRC_AND_LOC
:
7821 /* Print location and source line. */
7822 source_flag
= SRC_AND_LOC
;
7824 case PRINT_SRC_ONLY
:
7825 source_flag
= SRC_LINE
;
7828 /* Something bogus. */
7829 source_flag
= SRC_LINE
;
7830 do_frame_printing
= 0;
7833 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
7836 /* The behavior of this routine with respect to the source
7838 SRC_LINE: Print only source line
7839 LOCATION: Print only location
7840 SRC_AND_LOC: Print location and source line. */
7841 if (do_frame_printing
)
7842 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
7848 print_stop_event (struct ui_out
*uiout
, bool displays
)
7850 struct target_waitstatus last
;
7852 struct thread_info
*tp
;
7854 get_last_target_status (&last_ptid
, &last
);
7857 scoped_restore save_uiout
= make_scoped_restore (¤t_uiout
, uiout
);
7859 print_stop_location (&last
);
7861 /* Display the auto-display expressions. */
7866 tp
= inferior_thread ();
7867 if (tp
->thread_fsm
!= NULL
7868 && tp
->thread_fsm
->finished_p ())
7870 struct return_value_info
*rv
;
7872 rv
= tp
->thread_fsm
->return_value ();
7874 print_return_value (uiout
, rv
);
7881 maybe_remove_breakpoints (void)
7883 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
7885 if (remove_breakpoints ())
7887 target_terminal::ours_for_output ();
7888 printf_filtered (_("Cannot remove breakpoints because "
7889 "program is no longer writable.\nFurther "
7890 "execution is probably impossible.\n"));
7895 /* The execution context that just caused a normal stop. */
7902 DISABLE_COPY_AND_ASSIGN (stop_context
);
7904 bool changed () const;
7909 /* The event PTID. */
7913 /* If stopp for a thread event, this is the thread that caused the
7915 struct thread_info
*thread
;
7917 /* The inferior that caused the stop. */
7921 /* Initializes a new stop context. If stopped for a thread event, this
7922 takes a strong reference to the thread. */
7924 stop_context::stop_context ()
7926 stop_id
= get_stop_id ();
7927 ptid
= inferior_ptid
;
7928 inf_num
= current_inferior ()->num
;
7930 if (inferior_ptid
!= null_ptid
)
7932 /* Take a strong reference so that the thread can't be deleted
7934 thread
= inferior_thread ();
7941 /* Release a stop context previously created with save_stop_context.
7942 Releases the strong reference to the thread as well. */
7944 stop_context::~stop_context ()
7950 /* Return true if the current context no longer matches the saved stop
7954 stop_context::changed () const
7956 if (ptid
!= inferior_ptid
)
7958 if (inf_num
!= current_inferior ()->num
)
7960 if (thread
!= NULL
&& thread
->state
!= THREAD_STOPPED
)
7962 if (get_stop_id () != stop_id
)
7972 struct target_waitstatus last
;
7975 get_last_target_status (&last_ptid
, &last
);
7979 /* If an exception is thrown from this point on, make sure to
7980 propagate GDB's knowledge of the executing state to the
7981 frontend/user running state. A QUIT is an easy exception to see
7982 here, so do this before any filtered output. */
7984 gdb::optional
<scoped_finish_thread_state
> maybe_finish_thread_state
;
7987 maybe_finish_thread_state
.emplace (minus_one_ptid
);
7988 else if (last
.kind
== TARGET_WAITKIND_SIGNALLED
7989 || last
.kind
== TARGET_WAITKIND_EXITED
)
7991 /* On some targets, we may still have live threads in the
7992 inferior when we get a process exit event. E.g., for
7993 "checkpoint", when the current checkpoint/fork exits,
7994 linux-fork.c automatically switches to another fork from
7995 within target_mourn_inferior. */
7996 if (inferior_ptid
!= null_ptid
)
7997 maybe_finish_thread_state
.emplace (ptid_t (inferior_ptid
.pid ()));
7999 else if (last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8000 maybe_finish_thread_state
.emplace (inferior_ptid
);
8002 /* As we're presenting a stop, and potentially removing breakpoints,
8003 update the thread list so we can tell whether there are threads
8004 running on the target. With target remote, for example, we can
8005 only learn about new threads when we explicitly update the thread
8006 list. Do this before notifying the interpreters about signal
8007 stops, end of stepping ranges, etc., so that the "new thread"
8008 output is emitted before e.g., "Program received signal FOO",
8009 instead of after. */
8010 update_thread_list ();
8012 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
8013 gdb::observers::signal_received
.notify (inferior_thread ()->suspend
.stop_signal
);
8015 /* As with the notification of thread events, we want to delay
8016 notifying the user that we've switched thread context until
8017 the inferior actually stops.
8019 There's no point in saying anything if the inferior has exited.
8020 Note that SIGNALLED here means "exited with a signal", not
8021 "received a signal".
8023 Also skip saying anything in non-stop mode. In that mode, as we
8024 don't want GDB to switch threads behind the user's back, to avoid
8025 races where the user is typing a command to apply to thread x,
8026 but GDB switches to thread y before the user finishes entering
8027 the command, fetch_inferior_event installs a cleanup to restore
8028 the current thread back to the thread the user had selected right
8029 after this event is handled, so we're not really switching, only
8030 informing of a stop. */
8032 && previous_inferior_ptid
!= inferior_ptid
8033 && target_has_execution
8034 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
8035 && last
.kind
!= TARGET_WAITKIND_EXITED
8036 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8038 SWITCH_THRU_ALL_UIS ()
8040 target_terminal::ours_for_output ();
8041 printf_filtered (_("[Switching to %s]\n"),
8042 target_pid_to_str (inferior_ptid
).c_str ());
8043 annotate_thread_changed ();
8045 previous_inferior_ptid
= inferior_ptid
;
8048 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
8050 SWITCH_THRU_ALL_UIS ()
8051 if (current_ui
->prompt_state
== PROMPT_BLOCKED
)
8053 target_terminal::ours_for_output ();
8054 printf_filtered (_("No unwaited-for children left.\n"));
8058 /* Note: this depends on the update_thread_list call above. */
8059 maybe_remove_breakpoints ();
8061 /* If an auto-display called a function and that got a signal,
8062 delete that auto-display to avoid an infinite recursion. */
8064 if (stopped_by_random_signal
)
8065 disable_current_display ();
8067 SWITCH_THRU_ALL_UIS ()
8069 async_enable_stdin ();
8072 /* Let the user/frontend see the threads as stopped. */
8073 maybe_finish_thread_state
.reset ();
8075 /* Select innermost stack frame - i.e., current frame is frame 0,
8076 and current location is based on that. Handle the case where the
8077 dummy call is returning after being stopped. E.g. the dummy call
8078 previously hit a breakpoint. (If the dummy call returns
8079 normally, we won't reach here.) Do this before the stop hook is
8080 run, so that it doesn't get to see the temporary dummy frame,
8081 which is not where we'll present the stop. */
8082 if (has_stack_frames ())
8084 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
8086 /* Pop the empty frame that contains the stack dummy. This
8087 also restores inferior state prior to the call (struct
8088 infcall_suspend_state). */
8089 struct frame_info
*frame
= get_current_frame ();
8091 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
8093 /* frame_pop calls reinit_frame_cache as the last thing it
8094 does which means there's now no selected frame. */
8097 select_frame (get_current_frame ());
8099 /* Set the current source location. */
8100 set_current_sal_from_frame (get_current_frame ());
8103 /* Look up the hook_stop and run it (CLI internally handles problem
8104 of stop_command's pre-hook not existing). */
8105 if (stop_command
!= NULL
)
8107 stop_context saved_context
;
8111 execute_cmd_pre_hook (stop_command
);
8113 CATCH (ex
, RETURN_MASK_ALL
)
8115 exception_fprintf (gdb_stderr
, ex
,
8116 "Error while running hook_stop:\n");
8120 /* If the stop hook resumes the target, then there's no point in
8121 trying to notify about the previous stop; its context is
8122 gone. Likewise if the command switches thread or inferior --
8123 the observers would print a stop for the wrong
8125 if (saved_context
.changed ())
8129 /* Notify observers about the stop. This is where the interpreters
8130 print the stop event. */
8131 if (inferior_ptid
!= null_ptid
)
8132 gdb::observers::normal_stop
.notify (inferior_thread ()->control
.stop_bpstat
,
8135 gdb::observers::normal_stop
.notify (NULL
, stop_print_frame
);
8137 annotate_stopped ();
8139 if (target_has_execution
)
8141 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
8142 && last
.kind
!= TARGET_WAITKIND_EXITED
8143 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8144 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8145 Delete any breakpoint that is to be deleted at the next stop. */
8146 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
8149 /* Try to get rid of automatically added inferiors that are no
8150 longer needed. Keeping those around slows down things linearly.
8151 Note that this never removes the current inferior. */
8158 signal_stop_state (int signo
)
8160 return signal_stop
[signo
];
8164 signal_print_state (int signo
)
8166 return signal_print
[signo
];
8170 signal_pass_state (int signo
)
8172 return signal_program
[signo
];
8176 signal_cache_update (int signo
)
8180 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
8181 signal_cache_update (signo
);
8186 signal_pass
[signo
] = (signal_stop
[signo
] == 0
8187 && signal_print
[signo
] == 0
8188 && signal_program
[signo
] == 1
8189 && signal_catch
[signo
] == 0);
8193 signal_stop_update (int signo
, int state
)
8195 int ret
= signal_stop
[signo
];
8197 signal_stop
[signo
] = state
;
8198 signal_cache_update (signo
);
8203 signal_print_update (int signo
, int state
)
8205 int ret
= signal_print
[signo
];
8207 signal_print
[signo
] = state
;
8208 signal_cache_update (signo
);
8213 signal_pass_update (int signo
, int state
)
8215 int ret
= signal_program
[signo
];
8217 signal_program
[signo
] = state
;
8218 signal_cache_update (signo
);
8222 /* Update the global 'signal_catch' from INFO and notify the
8226 signal_catch_update (const unsigned int *info
)
8230 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
8231 signal_catch
[i
] = info
[i
] > 0;
8232 signal_cache_update (-1);
8233 target_pass_signals (signal_pass
);
8237 sig_print_header (void)
8239 printf_filtered (_("Signal Stop\tPrint\tPass "
8240 "to program\tDescription\n"));
8244 sig_print_info (enum gdb_signal oursig
)
8246 const char *name
= gdb_signal_to_name (oursig
);
8247 int name_padding
= 13 - strlen (name
);
8249 if (name_padding
<= 0)
8252 printf_filtered ("%s", name
);
8253 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
8254 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
8255 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
8256 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
8257 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
8260 /* Specify how various signals in the inferior should be handled. */
8263 handle_command (const char *args
, int from_tty
)
8265 int digits
, wordlen
;
8266 int sigfirst
, siglast
;
8267 enum gdb_signal oursig
;
8272 error_no_arg (_("signal to handle"));
8275 /* Allocate and zero an array of flags for which signals to handle. */
8277 const size_t nsigs
= GDB_SIGNAL_LAST
;
8278 unsigned char sigs
[nsigs
] {};
8280 /* Break the command line up into args. */
8282 gdb_argv
built_argv (args
);
8284 /* Walk through the args, looking for signal oursigs, signal names, and
8285 actions. Signal numbers and signal names may be interspersed with
8286 actions, with the actions being performed for all signals cumulatively
8287 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8289 for (char *arg
: built_argv
)
8291 wordlen
= strlen (arg
);
8292 for (digits
= 0; isdigit (arg
[digits
]); digits
++)
8296 sigfirst
= siglast
= -1;
8298 if (wordlen
>= 1 && !strncmp (arg
, "all", wordlen
))
8300 /* Apply action to all signals except those used by the
8301 debugger. Silently skip those. */
8304 siglast
= nsigs
- 1;
8306 else if (wordlen
>= 1 && !strncmp (arg
, "stop", wordlen
))
8308 SET_SIGS (nsigs
, sigs
, signal_stop
);
8309 SET_SIGS (nsigs
, sigs
, signal_print
);
8311 else if (wordlen
>= 1 && !strncmp (arg
, "ignore", wordlen
))
8313 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8315 else if (wordlen
>= 2 && !strncmp (arg
, "print", wordlen
))
8317 SET_SIGS (nsigs
, sigs
, signal_print
);
8319 else if (wordlen
>= 2 && !strncmp (arg
, "pass", wordlen
))
8321 SET_SIGS (nsigs
, sigs
, signal_program
);
8323 else if (wordlen
>= 3 && !strncmp (arg
, "nostop", wordlen
))
8325 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8327 else if (wordlen
>= 3 && !strncmp (arg
, "noignore", wordlen
))
8329 SET_SIGS (nsigs
, sigs
, signal_program
);
8331 else if (wordlen
>= 4 && !strncmp (arg
, "noprint", wordlen
))
8333 UNSET_SIGS (nsigs
, sigs
, signal_print
);
8334 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8336 else if (wordlen
>= 4 && !strncmp (arg
, "nopass", wordlen
))
8338 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8340 else if (digits
> 0)
8342 /* It is numeric. The numeric signal refers to our own
8343 internal signal numbering from target.h, not to host/target
8344 signal number. This is a feature; users really should be
8345 using symbolic names anyway, and the common ones like
8346 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8348 sigfirst
= siglast
= (int)
8349 gdb_signal_from_command (atoi (arg
));
8350 if (arg
[digits
] == '-')
8353 gdb_signal_from_command (atoi (arg
+ digits
+ 1));
8355 if (sigfirst
> siglast
)
8357 /* Bet he didn't figure we'd think of this case... */
8358 std::swap (sigfirst
, siglast
);
8363 oursig
= gdb_signal_from_name (arg
);
8364 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
8366 sigfirst
= siglast
= (int) oursig
;
8370 /* Not a number and not a recognized flag word => complain. */
8371 error (_("Unrecognized or ambiguous flag word: \"%s\"."), arg
);
8375 /* If any signal numbers or symbol names were found, set flags for
8376 which signals to apply actions to. */
8378 for (int signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
8380 switch ((enum gdb_signal
) signum
)
8382 case GDB_SIGNAL_TRAP
:
8383 case GDB_SIGNAL_INT
:
8384 if (!allsigs
&& !sigs
[signum
])
8386 if (query (_("%s is used by the debugger.\n\
8387 Are you sure you want to change it? "),
8388 gdb_signal_to_name ((enum gdb_signal
) signum
)))
8393 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8397 case GDB_SIGNAL_DEFAULT
:
8398 case GDB_SIGNAL_UNKNOWN
:
8399 /* Make sure that "all" doesn't print these. */
8408 for (int signum
= 0; signum
< nsigs
; signum
++)
8411 signal_cache_update (-1);
8412 target_pass_signals (signal_pass
);
8413 target_program_signals (signal_program
);
8417 /* Show the results. */
8418 sig_print_header ();
8419 for (; signum
< nsigs
; signum
++)
8421 sig_print_info ((enum gdb_signal
) signum
);
8428 /* Complete the "handle" command. */
8431 handle_completer (struct cmd_list_element
*ignore
,
8432 completion_tracker
&tracker
,
8433 const char *text
, const char *word
)
8435 static const char * const keywords
[] =
8449 signal_completer (ignore
, tracker
, text
, word
);
8450 complete_on_enum (tracker
, keywords
, word
, word
);
8454 gdb_signal_from_command (int num
)
8456 if (num
>= 1 && num
<= 15)
8457 return (enum gdb_signal
) num
;
8458 error (_("Only signals 1-15 are valid as numeric signals.\n\
8459 Use \"info signals\" for a list of symbolic signals."));
8462 /* Print current contents of the tables set by the handle command.
8463 It is possible we should just be printing signals actually used
8464 by the current target (but for things to work right when switching
8465 targets, all signals should be in the signal tables). */
8468 info_signals_command (const char *signum_exp
, int from_tty
)
8470 enum gdb_signal oursig
;
8472 sig_print_header ();
8476 /* First see if this is a symbol name. */
8477 oursig
= gdb_signal_from_name (signum_exp
);
8478 if (oursig
== GDB_SIGNAL_UNKNOWN
)
8480 /* No, try numeric. */
8482 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
8484 sig_print_info (oursig
);
8488 printf_filtered ("\n");
8489 /* These ugly casts brought to you by the native VAX compiler. */
8490 for (oursig
= GDB_SIGNAL_FIRST
;
8491 (int) oursig
< (int) GDB_SIGNAL_LAST
;
8492 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
8496 if (oursig
!= GDB_SIGNAL_UNKNOWN
8497 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
8498 sig_print_info (oursig
);
8501 printf_filtered (_("\nUse the \"handle\" command "
8502 "to change these tables.\n"));
8505 /* The $_siginfo convenience variable is a bit special. We don't know
8506 for sure the type of the value until we actually have a chance to
8507 fetch the data. The type can change depending on gdbarch, so it is
8508 also dependent on which thread you have selected.
8510 1. making $_siginfo be an internalvar that creates a new value on
8513 2. making the value of $_siginfo be an lval_computed value. */
8515 /* This function implements the lval_computed support for reading a
8519 siginfo_value_read (struct value
*v
)
8521 LONGEST transferred
;
8523 /* If we can access registers, so can we access $_siginfo. Likewise
8525 validate_registers_access ();
8528 target_read (current_top_target (), TARGET_OBJECT_SIGNAL_INFO
,
8530 value_contents_all_raw (v
),
8532 TYPE_LENGTH (value_type (v
)));
8534 if (transferred
!= TYPE_LENGTH (value_type (v
)))
8535 error (_("Unable to read siginfo"));
8538 /* This function implements the lval_computed support for writing a
8542 siginfo_value_write (struct value
*v
, struct value
*fromval
)
8544 LONGEST transferred
;
8546 /* If we can access registers, so can we access $_siginfo. Likewise
8548 validate_registers_access ();
8550 transferred
= target_write (current_top_target (),
8551 TARGET_OBJECT_SIGNAL_INFO
,
8553 value_contents_all_raw (fromval
),
8555 TYPE_LENGTH (value_type (fromval
)));
8557 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
8558 error (_("Unable to write siginfo"));
8561 static const struct lval_funcs siginfo_value_funcs
=
8567 /* Return a new value with the correct type for the siginfo object of
8568 the current thread using architecture GDBARCH. Return a void value
8569 if there's no object available. */
8571 static struct value
*
8572 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
8575 if (target_has_stack
8576 && inferior_ptid
!= null_ptid
8577 && gdbarch_get_siginfo_type_p (gdbarch
))
8579 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8581 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
8584 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
8588 /* infcall_suspend_state contains state about the program itself like its
8589 registers and any signal it received when it last stopped.
8590 This state must be restored regardless of how the inferior function call
8591 ends (either successfully, or after it hits a breakpoint or signal)
8592 if the program is to properly continue where it left off. */
8594 class infcall_suspend_state
8597 /* Capture state from GDBARCH, TP, and REGCACHE that must be restored
8598 once the inferior function call has finished. */
8599 infcall_suspend_state (struct gdbarch
*gdbarch
,
8600 const struct thread_info
*tp
,
8601 struct regcache
*regcache
)
8602 : m_thread_suspend (tp
->suspend
),
8603 m_registers (new readonly_detached_regcache (*regcache
))
8605 gdb::unique_xmalloc_ptr
<gdb_byte
> siginfo_data
;
8607 if (gdbarch_get_siginfo_type_p (gdbarch
))
8609 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8610 size_t len
= TYPE_LENGTH (type
);
8612 siginfo_data
.reset ((gdb_byte
*) xmalloc (len
));
8614 if (target_read (current_top_target (), TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8615 siginfo_data
.get (), 0, len
) != len
)
8617 /* Errors ignored. */
8618 siginfo_data
.reset (nullptr);
8624 m_siginfo_gdbarch
= gdbarch
;
8625 m_siginfo_data
= std::move (siginfo_data
);
8629 /* Return a pointer to the stored register state. */
8631 readonly_detached_regcache
*registers () const
8633 return m_registers
.get ();
8636 /* Restores the stored state into GDBARCH, TP, and REGCACHE. */
8638 void restore (struct gdbarch
*gdbarch
,
8639 struct thread_info
*tp
,
8640 struct regcache
*regcache
) const
8642 tp
->suspend
= m_thread_suspend
;
8644 if (m_siginfo_gdbarch
== gdbarch
)
8646 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8648 /* Errors ignored. */
8649 target_write (current_top_target (), TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8650 m_siginfo_data
.get (), 0, TYPE_LENGTH (type
));
8653 /* The inferior can be gone if the user types "print exit(0)"
8654 (and perhaps other times). */
8655 if (target_has_execution
)
8656 /* NB: The register write goes through to the target. */
8657 regcache
->restore (registers ());
8661 /* How the current thread stopped before the inferior function call was
8663 struct thread_suspend_state m_thread_suspend
;
8665 /* The registers before the inferior function call was executed. */
8666 std::unique_ptr
<readonly_detached_regcache
> m_registers
;
8668 /* Format of SIGINFO_DATA or NULL if it is not present. */
8669 struct gdbarch
*m_siginfo_gdbarch
= nullptr;
8671 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
8672 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
8673 content would be invalid. */
8674 gdb::unique_xmalloc_ptr
<gdb_byte
> m_siginfo_data
;
8677 infcall_suspend_state_up
8678 save_infcall_suspend_state ()
8680 struct thread_info
*tp
= inferior_thread ();
8681 struct regcache
*regcache
= get_current_regcache ();
8682 struct gdbarch
*gdbarch
= regcache
->arch ();
8684 infcall_suspend_state_up inf_state
8685 (new struct infcall_suspend_state (gdbarch
, tp
, regcache
));
8687 /* Having saved the current state, adjust the thread state, discarding
8688 any stop signal information. The stop signal is not useful when
8689 starting an inferior function call, and run_inferior_call will not use
8690 the signal due to its `proceed' call with GDB_SIGNAL_0. */
8691 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
8696 /* Restore inferior session state to INF_STATE. */
8699 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8701 struct thread_info
*tp
= inferior_thread ();
8702 struct regcache
*regcache
= get_current_regcache ();
8703 struct gdbarch
*gdbarch
= regcache
->arch ();
8705 inf_state
->restore (gdbarch
, tp
, regcache
);
8706 discard_infcall_suspend_state (inf_state
);
8710 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8715 readonly_detached_regcache
*
8716 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
8718 return inf_state
->registers ();
8721 /* infcall_control_state contains state regarding gdb's control of the
8722 inferior itself like stepping control. It also contains session state like
8723 the user's currently selected frame. */
8725 struct infcall_control_state
8727 struct thread_control_state thread_control
;
8728 struct inferior_control_state inferior_control
;
8731 enum stop_stack_kind stop_stack_dummy
= STOP_NONE
;
8732 int stopped_by_random_signal
= 0;
8734 /* ID if the selected frame when the inferior function call was made. */
8735 struct frame_id selected_frame_id
{};
8738 /* Save all of the information associated with the inferior<==>gdb
8741 infcall_control_state_up
8742 save_infcall_control_state ()
8744 infcall_control_state_up
inf_status (new struct infcall_control_state
);
8745 struct thread_info
*tp
= inferior_thread ();
8746 struct inferior
*inf
= current_inferior ();
8748 inf_status
->thread_control
= tp
->control
;
8749 inf_status
->inferior_control
= inf
->control
;
8751 tp
->control
.step_resume_breakpoint
= NULL
;
8752 tp
->control
.exception_resume_breakpoint
= NULL
;
8754 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
8755 chain. If caller's caller is walking the chain, they'll be happier if we
8756 hand them back the original chain when restore_infcall_control_state is
8758 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
8761 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
8762 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
8764 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
8770 restore_selected_frame (const frame_id
&fid
)
8772 frame_info
*frame
= frame_find_by_id (fid
);
8774 /* If inf_status->selected_frame_id is NULL, there was no previously
8778 warning (_("Unable to restore previously selected frame."));
8782 select_frame (frame
);
8785 /* Restore inferior session state to INF_STATUS. */
8788 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
8790 struct thread_info
*tp
= inferior_thread ();
8791 struct inferior
*inf
= current_inferior ();
8793 if (tp
->control
.step_resume_breakpoint
)
8794 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
8796 if (tp
->control
.exception_resume_breakpoint
)
8797 tp
->control
.exception_resume_breakpoint
->disposition
8798 = disp_del_at_next_stop
;
8800 /* Handle the bpstat_copy of the chain. */
8801 bpstat_clear (&tp
->control
.stop_bpstat
);
8803 tp
->control
= inf_status
->thread_control
;
8804 inf
->control
= inf_status
->inferior_control
;
8807 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
8808 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
8810 if (target_has_stack
)
8812 /* The point of the try/catch is that if the stack is clobbered,
8813 walking the stack might encounter a garbage pointer and
8814 error() trying to dereference it. */
8817 restore_selected_frame (inf_status
->selected_frame_id
);
8819 CATCH (ex
, RETURN_MASK_ERROR
)
8821 exception_fprintf (gdb_stderr
, ex
,
8822 "Unable to restore previously selected frame:\n");
8823 /* Error in restoring the selected frame. Select the
8825 select_frame (get_current_frame ());
8834 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
8836 if (inf_status
->thread_control
.step_resume_breakpoint
)
8837 inf_status
->thread_control
.step_resume_breakpoint
->disposition
8838 = disp_del_at_next_stop
;
8840 if (inf_status
->thread_control
.exception_resume_breakpoint
)
8841 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
8842 = disp_del_at_next_stop
;
8844 /* See save_infcall_control_state for info on stop_bpstat. */
8845 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
8853 clear_exit_convenience_vars (void)
8855 clear_internalvar (lookup_internalvar ("_exitsignal"));
8856 clear_internalvar (lookup_internalvar ("_exitcode"));
8860 /* User interface for reverse debugging:
8861 Set exec-direction / show exec-direction commands
8862 (returns error unless target implements to_set_exec_direction method). */
8864 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
8865 static const char exec_forward
[] = "forward";
8866 static const char exec_reverse
[] = "reverse";
8867 static const char *exec_direction
= exec_forward
;
8868 static const char *const exec_direction_names
[] = {
8875 set_exec_direction_func (const char *args
, int from_tty
,
8876 struct cmd_list_element
*cmd
)
8878 if (target_can_execute_reverse
)
8880 if (!strcmp (exec_direction
, exec_forward
))
8881 execution_direction
= EXEC_FORWARD
;
8882 else if (!strcmp (exec_direction
, exec_reverse
))
8883 execution_direction
= EXEC_REVERSE
;
8887 exec_direction
= exec_forward
;
8888 error (_("Target does not support this operation."));
8893 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
8894 struct cmd_list_element
*cmd
, const char *value
)
8896 switch (execution_direction
) {
8898 fprintf_filtered (out
, _("Forward.\n"));
8901 fprintf_filtered (out
, _("Reverse.\n"));
8904 internal_error (__FILE__
, __LINE__
,
8905 _("bogus execution_direction value: %d"),
8906 (int) execution_direction
);
8911 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
8912 struct cmd_list_element
*c
, const char *value
)
8914 fprintf_filtered (file
, _("Resuming the execution of threads "
8915 "of all processes is %s.\n"), value
);
8918 /* Implementation of `siginfo' variable. */
8920 static const struct internalvar_funcs siginfo_funcs
=
8927 /* Callback for infrun's target events source. This is marked when a
8928 thread has a pending status to process. */
8931 infrun_async_inferior_event_handler (gdb_client_data data
)
8933 inferior_event_handler (INF_REG_EVENT
, NULL
);
8937 _initialize_infrun (void)
8939 struct cmd_list_element
*c
;
8941 /* Register extra event sources in the event loop. */
8942 infrun_async_inferior_event_token
8943 = create_async_event_handler (infrun_async_inferior_event_handler
, NULL
);
8945 add_info ("signals", info_signals_command
, _("\
8946 What debugger does when program gets various signals.\n\
8947 Specify a signal as argument to print info on that signal only."));
8948 add_info_alias ("handle", "signals", 0);
8950 c
= add_com ("handle", class_run
, handle_command
, _("\
8951 Specify how to handle signals.\n\
8952 Usage: handle SIGNAL [ACTIONS]\n\
8953 Args are signals and actions to apply to those signals.\n\
8954 If no actions are specified, the current settings for the specified signals\n\
8955 will be displayed instead.\n\
8957 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
8958 from 1-15 are allowed for compatibility with old versions of GDB.\n\
8959 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
8960 The special arg \"all\" is recognized to mean all signals except those\n\
8961 used by the debugger, typically SIGTRAP and SIGINT.\n\
8963 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
8964 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
8965 Stop means reenter debugger if this signal happens (implies print).\n\
8966 Print means print a message if this signal happens.\n\
8967 Pass means let program see this signal; otherwise program doesn't know.\n\
8968 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
8969 Pass and Stop may be combined.\n\
8971 Multiple signals may be specified. Signal numbers and signal names\n\
8972 may be interspersed with actions, with the actions being performed for\n\
8973 all signals cumulatively specified."));
8974 set_cmd_completer (c
, handle_completer
);
8977 stop_command
= add_cmd ("stop", class_obscure
,
8978 not_just_help_class_command
, _("\
8979 There is no `stop' command, but you can set a hook on `stop'.\n\
8980 This allows you to set a list of commands to be run each time execution\n\
8981 of the program stops."), &cmdlist
);
8983 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
8984 Set inferior debugging."), _("\
8985 Show inferior debugging."), _("\
8986 When non-zero, inferior specific debugging is enabled."),
8989 &setdebuglist
, &showdebuglist
);
8991 add_setshow_boolean_cmd ("displaced", class_maintenance
,
8992 &debug_displaced
, _("\
8993 Set displaced stepping debugging."), _("\
8994 Show displaced stepping debugging."), _("\
8995 When non-zero, displaced stepping specific debugging is enabled."),
8997 show_debug_displaced
,
8998 &setdebuglist
, &showdebuglist
);
9000 add_setshow_boolean_cmd ("non-stop", no_class
,
9002 Set whether gdb controls the inferior in non-stop mode."), _("\
9003 Show whether gdb controls the inferior in non-stop mode."), _("\
9004 When debugging a multi-threaded program and this setting is\n\
9005 off (the default, also called all-stop mode), when one thread stops\n\
9006 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9007 all other threads in the program while you interact with the thread of\n\
9008 interest. When you continue or step a thread, you can allow the other\n\
9009 threads to run, or have them remain stopped, but while you inspect any\n\
9010 thread's state, all threads stop.\n\
9012 In non-stop mode, when one thread stops, other threads can continue\n\
9013 to run freely. You'll be able to step each thread independently,\n\
9014 leave it stopped or free to run as needed."),
9020 for (size_t i
= 0; i
< GDB_SIGNAL_LAST
; i
++)
9023 signal_print
[i
] = 1;
9024 signal_program
[i
] = 1;
9025 signal_catch
[i
] = 0;
9028 /* Signals caused by debugger's own actions should not be given to
9029 the program afterwards.
9031 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9032 explicitly specifies that it should be delivered to the target
9033 program. Typically, that would occur when a user is debugging a
9034 target monitor on a simulator: the target monitor sets a
9035 breakpoint; the simulator encounters this breakpoint and halts
9036 the simulation handing control to GDB; GDB, noting that the stop
9037 address doesn't map to any known breakpoint, returns control back
9038 to the simulator; the simulator then delivers the hardware
9039 equivalent of a GDB_SIGNAL_TRAP to the program being
9041 signal_program
[GDB_SIGNAL_TRAP
] = 0;
9042 signal_program
[GDB_SIGNAL_INT
] = 0;
9044 /* Signals that are not errors should not normally enter the debugger. */
9045 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
9046 signal_print
[GDB_SIGNAL_ALRM
] = 0;
9047 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
9048 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
9049 signal_stop
[GDB_SIGNAL_PROF
] = 0;
9050 signal_print
[GDB_SIGNAL_PROF
] = 0;
9051 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
9052 signal_print
[GDB_SIGNAL_CHLD
] = 0;
9053 signal_stop
[GDB_SIGNAL_IO
] = 0;
9054 signal_print
[GDB_SIGNAL_IO
] = 0;
9055 signal_stop
[GDB_SIGNAL_POLL
] = 0;
9056 signal_print
[GDB_SIGNAL_POLL
] = 0;
9057 signal_stop
[GDB_SIGNAL_URG
] = 0;
9058 signal_print
[GDB_SIGNAL_URG
] = 0;
9059 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
9060 signal_print
[GDB_SIGNAL_WINCH
] = 0;
9061 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
9062 signal_print
[GDB_SIGNAL_PRIO
] = 0;
9064 /* These signals are used internally by user-level thread
9065 implementations. (See signal(5) on Solaris.) Like the above
9066 signals, a healthy program receives and handles them as part of
9067 its normal operation. */
9068 signal_stop
[GDB_SIGNAL_LWP
] = 0;
9069 signal_print
[GDB_SIGNAL_LWP
] = 0;
9070 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
9071 signal_print
[GDB_SIGNAL_WAITING
] = 0;
9072 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
9073 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
9074 signal_stop
[GDB_SIGNAL_LIBRT
] = 0;
9075 signal_print
[GDB_SIGNAL_LIBRT
] = 0;
9077 /* Update cached state. */
9078 signal_cache_update (-1);
9080 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
9081 &stop_on_solib_events
, _("\
9082 Set stopping for shared library events."), _("\
9083 Show stopping for shared library events."), _("\
9084 If nonzero, gdb will give control to the user when the dynamic linker\n\
9085 notifies gdb of shared library events. The most common event of interest\n\
9086 to the user would be loading/unloading of a new library."),
9087 set_stop_on_solib_events
,
9088 show_stop_on_solib_events
,
9089 &setlist
, &showlist
);
9091 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
9092 follow_fork_mode_kind_names
,
9093 &follow_fork_mode_string
, _("\
9094 Set debugger response to a program call of fork or vfork."), _("\
9095 Show debugger response to a program call of fork or vfork."), _("\
9096 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9097 parent - the original process is debugged after a fork\n\
9098 child - the new process is debugged after a fork\n\
9099 The unfollowed process will continue to run.\n\
9100 By default, the debugger will follow the parent process."),
9102 show_follow_fork_mode_string
,
9103 &setlist
, &showlist
);
9105 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
9106 follow_exec_mode_names
,
9107 &follow_exec_mode_string
, _("\
9108 Set debugger response to a program call of exec."), _("\
9109 Show debugger response to a program call of exec."), _("\
9110 An exec call replaces the program image of a process.\n\
9112 follow-exec-mode can be:\n\
9114 new - the debugger creates a new inferior and rebinds the process\n\
9115 to this new inferior. The program the process was running before\n\
9116 the exec call can be restarted afterwards by restarting the original\n\
9119 same - the debugger keeps the process bound to the same inferior.\n\
9120 The new executable image replaces the previous executable loaded in\n\
9121 the inferior. Restarting the inferior after the exec call restarts\n\
9122 the executable the process was running after the exec call.\n\
9124 By default, the debugger will use the same inferior."),
9126 show_follow_exec_mode_string
,
9127 &setlist
, &showlist
);
9129 add_setshow_enum_cmd ("scheduler-locking", class_run
,
9130 scheduler_enums
, &scheduler_mode
, _("\
9131 Set mode for locking scheduler during execution."), _("\
9132 Show mode for locking scheduler during execution."), _("\
9133 off == no locking (threads may preempt at any time)\n\
9134 on == full locking (no thread except the current thread may run)\n\
9135 This applies to both normal execution and replay mode.\n\
9136 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9137 In this mode, other threads may run during other commands.\n\
9138 This applies to both normal execution and replay mode.\n\
9139 replay == scheduler locked in replay mode and unlocked during normal execution."),
9140 set_schedlock_func
, /* traps on target vector */
9141 show_scheduler_mode
,
9142 &setlist
, &showlist
);
9144 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
9145 Set mode for resuming threads of all processes."), _("\
9146 Show mode for resuming threads of all processes."), _("\
9147 When on, execution commands (such as 'continue' or 'next') resume all\n\
9148 threads of all processes. When off (which is the default), execution\n\
9149 commands only resume the threads of the current process. The set of\n\
9150 threads that are resumed is further refined by the scheduler-locking\n\
9151 mode (see help set scheduler-locking)."),
9153 show_schedule_multiple
,
9154 &setlist
, &showlist
);
9156 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
9157 Set mode of the step operation."), _("\
9158 Show mode of the step operation."), _("\
9159 When set, doing a step over a function without debug line information\n\
9160 will stop at the first instruction of that function. Otherwise, the\n\
9161 function is skipped and the step command stops at a different source line."),
9163 show_step_stop_if_no_debug
,
9164 &setlist
, &showlist
);
9166 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
9167 &can_use_displaced_stepping
, _("\
9168 Set debugger's willingness to use displaced stepping."), _("\
9169 Show debugger's willingness to use displaced stepping."), _("\
9170 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9171 supported by the target architecture. If off, gdb will not use displaced\n\
9172 stepping to step over breakpoints, even if such is supported by the target\n\
9173 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9174 if the target architecture supports it and non-stop mode is active, but will not\n\
9175 use it in all-stop mode (see help set non-stop)."),
9177 show_can_use_displaced_stepping
,
9178 &setlist
, &showlist
);
9180 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
9181 &exec_direction
, _("Set direction of execution.\n\
9182 Options are 'forward' or 'reverse'."),
9183 _("Show direction of execution (forward/reverse)."),
9184 _("Tells gdb whether to execute forward or backward."),
9185 set_exec_direction_func
, show_exec_direction_func
,
9186 &setlist
, &showlist
);
9188 /* Set/show detach-on-fork: user-settable mode. */
9190 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
9191 Set whether gdb will detach the child of a fork."), _("\
9192 Show whether gdb will detach the child of a fork."), _("\
9193 Tells gdb whether to detach the child of a fork."),
9194 NULL
, NULL
, &setlist
, &showlist
);
9196 /* Set/show disable address space randomization mode. */
9198 add_setshow_boolean_cmd ("disable-randomization", class_support
,
9199 &disable_randomization
, _("\
9200 Set disabling of debuggee's virtual address space randomization."), _("\
9201 Show disabling of debuggee's virtual address space randomization."), _("\
9202 When this mode is on (which is the default), randomization of the virtual\n\
9203 address space is disabled. Standalone programs run with the randomization\n\
9204 enabled by default on some platforms."),
9205 &set_disable_randomization
,
9206 &show_disable_randomization
,
9207 &setlist
, &showlist
);
9209 /* ptid initializations */
9210 inferior_ptid
= null_ptid
;
9211 target_last_wait_ptid
= minus_one_ptid
;
9213 gdb::observers::thread_ptid_changed
.attach (infrun_thread_ptid_changed
);
9214 gdb::observers::thread_stop_requested
.attach (infrun_thread_stop_requested
);
9215 gdb::observers::thread_exit
.attach (infrun_thread_thread_exit
);
9216 gdb::observers::inferior_exit
.attach (infrun_inferior_exit
);
9218 /* Explicitly create without lookup, since that tries to create a
9219 value with a void typed value, and when we get here, gdbarch
9220 isn't initialized yet. At this point, we're quite sure there
9221 isn't another convenience variable of the same name. */
9222 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
9224 add_setshow_boolean_cmd ("observer", no_class
,
9225 &observer_mode_1
, _("\
9226 Set whether gdb controls the inferior in observer mode."), _("\
9227 Show whether gdb controls the inferior in observer mode."), _("\
9228 In observer mode, GDB can get data from the inferior, but not\n\
9229 affect its execution. Registers and memory may not be changed,\n\
9230 breakpoints may not be set, and the program cannot be interrupted\n\