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 "gdbsupport/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 "gdbsupport/enum-flags.h"
67 #include "progspace-and-thread.h"
68 #include "gdbsupport/gdb_optional.h"
69 #include "arch-utils.h"
70 #include "gdbsupport/scope-exit.h"
71 #include "gdbsupport/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. Break the bonds. */
919 inferior
*vfork_parent
= inf
->vfork_parent
;
920 inf
->vfork_parent
->vfork_child
= NULL
;
921 inf
->vfork_parent
= NULL
;
923 /* If the user wanted to detach from the parent, now is the
925 if (vfork_parent
->pending_detach
)
927 struct thread_info
*tp
;
928 struct program_space
*pspace
;
929 struct address_space
*aspace
;
931 /* follow-fork child, detach-on-fork on. */
933 vfork_parent
->pending_detach
= 0;
935 gdb::optional
<scoped_restore_exited_inferior
>
936 maybe_restore_inferior
;
937 gdb::optional
<scoped_restore_current_pspace_and_thread
>
938 maybe_restore_thread
;
940 /* If we're handling a child exit, then inferior_ptid points
941 at the inferior's pid, not to a thread. */
943 maybe_restore_inferior
.emplace ();
945 maybe_restore_thread
.emplace ();
947 /* We're letting loose of the parent. */
948 tp
= any_live_thread_of_inferior (vfork_parent
);
949 switch_to_thread (tp
);
951 /* We're about to detach from the parent, which implicitly
952 removes breakpoints from its address space. There's a
953 catch here: we want to reuse the spaces for the child,
954 but, parent/child are still sharing the pspace at this
955 point, although the exec in reality makes the kernel give
956 the child a fresh set of new pages. The problem here is
957 that the breakpoints module being unaware of this, would
958 likely chose the child process to write to the parent
959 address space. Swapping the child temporarily away from
960 the spaces has the desired effect. Yes, this is "sort
963 pspace
= inf
->pspace
;
964 aspace
= inf
->aspace
;
968 if (print_inferior_events
)
971 = target_pid_to_str (ptid_t (vfork_parent
->pid
));
973 target_terminal::ours_for_output ();
977 fprintf_filtered (gdb_stdlog
,
978 _("[Detaching vfork parent %s "
979 "after child exec]\n"), pidstr
.c_str ());
983 fprintf_filtered (gdb_stdlog
,
984 _("[Detaching vfork parent %s "
985 "after child exit]\n"), pidstr
.c_str ());
989 target_detach (vfork_parent
, 0);
992 inf
->pspace
= pspace
;
993 inf
->aspace
= aspace
;
997 /* We're staying attached to the parent, so, really give the
998 child a new address space. */
999 inf
->pspace
= new program_space (maybe_new_address_space ());
1000 inf
->aspace
= inf
->pspace
->aspace
;
1002 set_current_program_space (inf
->pspace
);
1004 resume_parent
= vfork_parent
->pid
;
1008 struct program_space
*pspace
;
1010 /* If this is a vfork child exiting, then the pspace and
1011 aspaces were shared with the parent. Since we're
1012 reporting the process exit, we'll be mourning all that is
1013 found in the address space, and switching to null_ptid,
1014 preparing to start a new inferior. But, since we don't
1015 want to clobber the parent's address/program spaces, we
1016 go ahead and create a new one for this exiting
1019 /* Switch to null_ptid while running clone_program_space, so
1020 that clone_program_space doesn't want to read the
1021 selected frame of a dead process. */
1022 scoped_restore restore_ptid
1023 = make_scoped_restore (&inferior_ptid
, null_ptid
);
1025 /* This inferior is dead, so avoid giving the breakpoints
1026 module the option to write through to it (cloning a
1027 program space resets breakpoints). */
1030 pspace
= new program_space (maybe_new_address_space ());
1031 set_current_program_space (pspace
);
1033 inf
->symfile_flags
= SYMFILE_NO_READ
;
1034 clone_program_space (pspace
, vfork_parent
->pspace
);
1035 inf
->pspace
= pspace
;
1036 inf
->aspace
= pspace
->aspace
;
1038 resume_parent
= vfork_parent
->pid
;
1041 gdb_assert (current_program_space
== inf
->pspace
);
1043 if (non_stop
&& resume_parent
!= -1)
1045 /* If the user wanted the parent to be running, let it go
1047 scoped_restore_current_thread restore_thread
;
1050 fprintf_unfiltered (gdb_stdlog
,
1051 "infrun: resuming vfork parent process %d\n",
1054 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
1059 /* Enum strings for "set|show follow-exec-mode". */
1061 static const char follow_exec_mode_new
[] = "new";
1062 static const char follow_exec_mode_same
[] = "same";
1063 static const char *const follow_exec_mode_names
[] =
1065 follow_exec_mode_new
,
1066 follow_exec_mode_same
,
1070 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1072 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1073 struct cmd_list_element
*c
, const char *value
)
1075 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1078 /* EXEC_FILE_TARGET is assumed to be non-NULL. */
1081 follow_exec (ptid_t ptid
, const char *exec_file_target
)
1083 struct inferior
*inf
= current_inferior ();
1084 int pid
= ptid
.pid ();
1085 ptid_t process_ptid
;
1087 /* Switch terminal for any messages produced e.g. by
1088 breakpoint_re_set. */
1089 target_terminal::ours_for_output ();
1091 /* This is an exec event that we actually wish to pay attention to.
1092 Refresh our symbol table to the newly exec'd program, remove any
1093 momentary bp's, etc.
1095 If there are breakpoints, they aren't really inserted now,
1096 since the exec() transformed our inferior into a fresh set
1099 We want to preserve symbolic breakpoints on the list, since
1100 we have hopes that they can be reset after the new a.out's
1101 symbol table is read.
1103 However, any "raw" breakpoints must be removed from the list
1104 (e.g., the solib bp's), since their address is probably invalid
1107 And, we DON'T want to call delete_breakpoints() here, since
1108 that may write the bp's "shadow contents" (the instruction
1109 value that was overwritten witha TRAP instruction). Since
1110 we now have a new a.out, those shadow contents aren't valid. */
1112 mark_breakpoints_out ();
1114 /* The target reports the exec event to the main thread, even if
1115 some other thread does the exec, and even if the main thread was
1116 stopped or already gone. We may still have non-leader threads of
1117 the process on our list. E.g., on targets that don't have thread
1118 exit events (like remote); or on native Linux in non-stop mode if
1119 there were only two threads in the inferior and the non-leader
1120 one is the one that execs (and nothing forces an update of the
1121 thread list up to here). When debugging remotely, it's best to
1122 avoid extra traffic, when possible, so avoid syncing the thread
1123 list with the target, and instead go ahead and delete all threads
1124 of the process but one that reported the event. Note this must
1125 be done before calling update_breakpoints_after_exec, as
1126 otherwise clearing the threads' resources would reference stale
1127 thread breakpoints -- it may have been one of these threads that
1128 stepped across the exec. We could just clear their stepping
1129 states, but as long as we're iterating, might as well delete
1130 them. Deleting them now rather than at the next user-visible
1131 stop provides a nicer sequence of events for user and MI
1133 for (thread_info
*th
: all_threads_safe ())
1134 if (th
->ptid
.pid () == pid
&& th
->ptid
!= ptid
)
1137 /* We also need to clear any left over stale state for the
1138 leader/event thread. E.g., if there was any step-resume
1139 breakpoint or similar, it's gone now. We cannot truly
1140 step-to-next statement through an exec(). */
1141 thread_info
*th
= inferior_thread ();
1142 th
->control
.step_resume_breakpoint
= NULL
;
1143 th
->control
.exception_resume_breakpoint
= NULL
;
1144 th
->control
.single_step_breakpoints
= NULL
;
1145 th
->control
.step_range_start
= 0;
1146 th
->control
.step_range_end
= 0;
1148 /* The user may have had the main thread held stopped in the
1149 previous image (e.g., schedlock on, or non-stop). Release
1151 th
->stop_requested
= 0;
1153 update_breakpoints_after_exec ();
1155 /* What is this a.out's name? */
1156 process_ptid
= ptid_t (pid
);
1157 printf_unfiltered (_("%s is executing new program: %s\n"),
1158 target_pid_to_str (process_ptid
).c_str (),
1161 /* We've followed the inferior through an exec. Therefore, the
1162 inferior has essentially been killed & reborn. */
1164 breakpoint_init_inferior (inf_execd
);
1166 gdb::unique_xmalloc_ptr
<char> exec_file_host
1167 = exec_file_find (exec_file_target
, NULL
);
1169 /* If we were unable to map the executable target pathname onto a host
1170 pathname, tell the user that. Otherwise GDB's subsequent behavior
1171 is confusing. Maybe it would even be better to stop at this point
1172 so that the user can specify a file manually before continuing. */
1173 if (exec_file_host
== NULL
)
1174 warning (_("Could not load symbols for executable %s.\n"
1175 "Do you need \"set sysroot\"?"),
1178 /* Reset the shared library package. This ensures that we get a
1179 shlib event when the child reaches "_start", at which point the
1180 dld will have had a chance to initialize the child. */
1181 /* Also, loading a symbol file below may trigger symbol lookups, and
1182 we don't want those to be satisfied by the libraries of the
1183 previous incarnation of this process. */
1184 no_shared_libraries (NULL
, 0);
1186 if (follow_exec_mode_string
== follow_exec_mode_new
)
1188 /* The user wants to keep the old inferior and program spaces
1189 around. Create a new fresh one, and switch to it. */
1191 /* Do exit processing for the original inferior before setting the new
1192 inferior's pid. Having two inferiors with the same pid would confuse
1193 find_inferior_p(t)id. Transfer the terminal state and info from the
1194 old to the new inferior. */
1195 inf
= add_inferior_with_spaces ();
1196 swap_terminal_info (inf
, current_inferior ());
1197 exit_inferior_silent (current_inferior ());
1200 target_follow_exec (inf
, exec_file_target
);
1202 set_current_inferior (inf
);
1203 set_current_program_space (inf
->pspace
);
1208 /* The old description may no longer be fit for the new image.
1209 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1210 old description; we'll read a new one below. No need to do
1211 this on "follow-exec-mode new", as the old inferior stays
1212 around (its description is later cleared/refetched on
1214 target_clear_description ();
1217 gdb_assert (current_program_space
== inf
->pspace
);
1219 /* Attempt to open the exec file. SYMFILE_DEFER_BP_RESET is used
1220 because the proper displacement for a PIE (Position Independent
1221 Executable) main symbol file will only be computed by
1222 solib_create_inferior_hook below. breakpoint_re_set would fail
1223 to insert the breakpoints with the zero displacement. */
1224 try_open_exec_file (exec_file_host
.get (), inf
, SYMFILE_DEFER_BP_RESET
);
1226 /* If the target can specify a description, read it. Must do this
1227 after flipping to the new executable (because the target supplied
1228 description must be compatible with the executable's
1229 architecture, and the old executable may e.g., be 32-bit, while
1230 the new one 64-bit), and before anything involving memory or
1232 target_find_description ();
1234 solib_create_inferior_hook (0);
1236 jit_inferior_created_hook ();
1238 breakpoint_re_set ();
1240 /* Reinsert all breakpoints. (Those which were symbolic have
1241 been reset to the proper address in the new a.out, thanks
1242 to symbol_file_command...). */
1243 insert_breakpoints ();
1245 /* The next resume of this inferior should bring it to the shlib
1246 startup breakpoints. (If the user had also set bp's on
1247 "main" from the old (parent) process, then they'll auto-
1248 matically get reset there in the new process.). */
1251 /* The queue of threads that need to do a step-over operation to get
1252 past e.g., a breakpoint. What technique is used to step over the
1253 breakpoint/watchpoint does not matter -- all threads end up in the
1254 same queue, to maintain rough temporal order of execution, in order
1255 to avoid starvation, otherwise, we could e.g., find ourselves
1256 constantly stepping the same couple threads past their breakpoints
1257 over and over, if the single-step finish fast enough. */
1258 struct thread_info
*step_over_queue_head
;
1260 /* Bit flags indicating what the thread needs to step over. */
1262 enum step_over_what_flag
1264 /* Step over a breakpoint. */
1265 STEP_OVER_BREAKPOINT
= 1,
1267 /* Step past a non-continuable watchpoint, in order to let the
1268 instruction execute so we can evaluate the watchpoint
1270 STEP_OVER_WATCHPOINT
= 2
1272 DEF_ENUM_FLAGS_TYPE (enum step_over_what_flag
, step_over_what
);
1274 /* Info about an instruction that is being stepped over. */
1276 struct step_over_info
1278 /* If we're stepping past a breakpoint, this is the address space
1279 and address of the instruction the breakpoint is set at. We'll
1280 skip inserting all breakpoints here. Valid iff ASPACE is
1282 const address_space
*aspace
;
1285 /* The instruction being stepped over triggers a nonsteppable
1286 watchpoint. If true, we'll skip inserting watchpoints. */
1287 int nonsteppable_watchpoint_p
;
1289 /* The thread's global number. */
1293 /* The step-over info of the location that is being stepped over.
1295 Note that with async/breakpoint always-inserted mode, a user might
1296 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1297 being stepped over. As setting a new breakpoint inserts all
1298 breakpoints, we need to make sure the breakpoint being stepped over
1299 isn't inserted then. We do that by only clearing the step-over
1300 info when the step-over is actually finished (or aborted).
1302 Presently GDB can only step over one breakpoint at any given time.
1303 Given threads that can't run code in the same address space as the
1304 breakpoint's can't really miss the breakpoint, GDB could be taught
1305 to step-over at most one breakpoint per address space (so this info
1306 could move to the address space object if/when GDB is extended).
1307 The set of breakpoints being stepped over will normally be much
1308 smaller than the set of all breakpoints, so a flag in the
1309 breakpoint location structure would be wasteful. A separate list
1310 also saves complexity and run-time, as otherwise we'd have to go
1311 through all breakpoint locations clearing their flag whenever we
1312 start a new sequence. Similar considerations weigh against storing
1313 this info in the thread object. Plus, not all step overs actually
1314 have breakpoint locations -- e.g., stepping past a single-step
1315 breakpoint, or stepping to complete a non-continuable
1317 static struct step_over_info step_over_info
;
1319 /* Record the address of the breakpoint/instruction we're currently
1321 N.B. We record the aspace and address now, instead of say just the thread,
1322 because when we need the info later the thread may be running. */
1325 set_step_over_info (const address_space
*aspace
, CORE_ADDR address
,
1326 int nonsteppable_watchpoint_p
,
1329 step_over_info
.aspace
= aspace
;
1330 step_over_info
.address
= address
;
1331 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1332 step_over_info
.thread
= thread
;
1335 /* Called when we're not longer stepping over a breakpoint / an
1336 instruction, so all breakpoints are free to be (re)inserted. */
1339 clear_step_over_info (void)
1342 fprintf_unfiltered (gdb_stdlog
,
1343 "infrun: clear_step_over_info\n");
1344 step_over_info
.aspace
= NULL
;
1345 step_over_info
.address
= 0;
1346 step_over_info
.nonsteppable_watchpoint_p
= 0;
1347 step_over_info
.thread
= -1;
1353 stepping_past_instruction_at (struct address_space
*aspace
,
1356 return (step_over_info
.aspace
!= NULL
1357 && breakpoint_address_match (aspace
, address
,
1358 step_over_info
.aspace
,
1359 step_over_info
.address
));
1365 thread_is_stepping_over_breakpoint (int thread
)
1367 return (step_over_info
.thread
!= -1
1368 && thread
== step_over_info
.thread
);
1374 stepping_past_nonsteppable_watchpoint (void)
1376 return step_over_info
.nonsteppable_watchpoint_p
;
1379 /* Returns true if step-over info is valid. */
1382 step_over_info_valid_p (void)
1384 return (step_over_info
.aspace
!= NULL
1385 || stepping_past_nonsteppable_watchpoint ());
1389 /* Displaced stepping. */
1391 /* In non-stop debugging mode, we must take special care to manage
1392 breakpoints properly; in particular, the traditional strategy for
1393 stepping a thread past a breakpoint it has hit is unsuitable.
1394 'Displaced stepping' is a tactic for stepping one thread past a
1395 breakpoint it has hit while ensuring that other threads running
1396 concurrently will hit the breakpoint as they should.
1398 The traditional way to step a thread T off a breakpoint in a
1399 multi-threaded program in all-stop mode is as follows:
1401 a0) Initially, all threads are stopped, and breakpoints are not
1403 a1) We single-step T, leaving breakpoints uninserted.
1404 a2) We insert breakpoints, and resume all threads.
1406 In non-stop debugging, however, this strategy is unsuitable: we
1407 don't want to have to stop all threads in the system in order to
1408 continue or step T past a breakpoint. Instead, we use displaced
1411 n0) Initially, T is stopped, other threads are running, and
1412 breakpoints are inserted.
1413 n1) We copy the instruction "under" the breakpoint to a separate
1414 location, outside the main code stream, making any adjustments
1415 to the instruction, register, and memory state as directed by
1417 n2) We single-step T over the instruction at its new location.
1418 n3) We adjust the resulting register and memory state as directed
1419 by T's architecture. This includes resetting T's PC to point
1420 back into the main instruction stream.
1423 This approach depends on the following gdbarch methods:
1425 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1426 indicate where to copy the instruction, and how much space must
1427 be reserved there. We use these in step n1.
1429 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1430 address, and makes any necessary adjustments to the instruction,
1431 register contents, and memory. We use this in step n1.
1433 - gdbarch_displaced_step_fixup adjusts registers and memory after
1434 we have successfuly single-stepped the instruction, to yield the
1435 same effect the instruction would have had if we had executed it
1436 at its original address. We use this in step n3.
1438 The gdbarch_displaced_step_copy_insn and
1439 gdbarch_displaced_step_fixup functions must be written so that
1440 copying an instruction with gdbarch_displaced_step_copy_insn,
1441 single-stepping across the copied instruction, and then applying
1442 gdbarch_displaced_insn_fixup should have the same effects on the
1443 thread's memory and registers as stepping the instruction in place
1444 would have. Exactly which responsibilities fall to the copy and
1445 which fall to the fixup is up to the author of those functions.
1447 See the comments in gdbarch.sh for details.
1449 Note that displaced stepping and software single-step cannot
1450 currently be used in combination, although with some care I think
1451 they could be made to. Software single-step works by placing
1452 breakpoints on all possible subsequent instructions; if the
1453 displaced instruction is a PC-relative jump, those breakpoints
1454 could fall in very strange places --- on pages that aren't
1455 executable, or at addresses that are not proper instruction
1456 boundaries. (We do generally let other threads run while we wait
1457 to hit the software single-step breakpoint, and they might
1458 encounter such a corrupted instruction.) One way to work around
1459 this would be to have gdbarch_displaced_step_copy_insn fully
1460 simulate the effect of PC-relative instructions (and return NULL)
1461 on architectures that use software single-stepping.
1463 In non-stop mode, we can have independent and simultaneous step
1464 requests, so more than one thread may need to simultaneously step
1465 over a breakpoint. The current implementation assumes there is
1466 only one scratch space per process. In this case, we have to
1467 serialize access to the scratch space. If thread A wants to step
1468 over a breakpoint, but we are currently waiting for some other
1469 thread to complete a displaced step, we leave thread A stopped and
1470 place it in the displaced_step_request_queue. Whenever a displaced
1471 step finishes, we pick the next thread in the queue and start a new
1472 displaced step operation on it. See displaced_step_prepare and
1473 displaced_step_fixup for details. */
1475 /* Default destructor for displaced_step_closure. */
1477 displaced_step_closure::~displaced_step_closure () = default;
1479 /* Get the displaced stepping state of process PID. */
1481 static displaced_step_inferior_state
*
1482 get_displaced_stepping_state (inferior
*inf
)
1484 return &inf
->displaced_step_state
;
1487 /* Returns true if any inferior has a thread doing a displaced
1491 displaced_step_in_progress_any_inferior ()
1493 for (inferior
*i
: all_inferiors ())
1495 if (i
->displaced_step_state
.step_thread
!= nullptr)
1502 /* Return true if thread represented by PTID is doing a displaced
1506 displaced_step_in_progress_thread (thread_info
*thread
)
1508 gdb_assert (thread
!= NULL
);
1510 return get_displaced_stepping_state (thread
->inf
)->step_thread
== thread
;
1513 /* Return true if process PID has a thread doing a displaced step. */
1516 displaced_step_in_progress (inferior
*inf
)
1518 return get_displaced_stepping_state (inf
)->step_thread
!= nullptr;
1521 /* If inferior is in displaced stepping, and ADDR equals to starting address
1522 of copy area, return corresponding displaced_step_closure. Otherwise,
1525 struct displaced_step_closure
*
1526 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1528 displaced_step_inferior_state
*displaced
1529 = get_displaced_stepping_state (current_inferior ());
1531 /* If checking the mode of displaced instruction in copy area. */
1532 if (displaced
->step_thread
!= nullptr
1533 && displaced
->step_copy
== addr
)
1534 return displaced
->step_closure
;
1540 infrun_inferior_exit (struct inferior
*inf
)
1542 inf
->displaced_step_state
.reset ();
1545 /* If ON, and the architecture supports it, GDB will use displaced
1546 stepping to step over breakpoints. If OFF, or if the architecture
1547 doesn't support it, GDB will instead use the traditional
1548 hold-and-step approach. If AUTO (which is the default), GDB will
1549 decide which technique to use to step over breakpoints depending on
1550 which of all-stop or non-stop mode is active --- displaced stepping
1551 in non-stop mode; hold-and-step in all-stop mode. */
1553 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1556 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1557 struct cmd_list_element
*c
,
1560 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1561 fprintf_filtered (file
,
1562 _("Debugger's willingness to use displaced stepping "
1563 "to step over breakpoints is %s (currently %s).\n"),
1564 value
, target_is_non_stop_p () ? "on" : "off");
1566 fprintf_filtered (file
,
1567 _("Debugger's willingness to use displaced stepping "
1568 "to step over breakpoints is %s.\n"), value
);
1571 /* Return non-zero if displaced stepping can/should be used to step
1572 over breakpoints of thread TP. */
1575 use_displaced_stepping (struct thread_info
*tp
)
1577 struct regcache
*regcache
= get_thread_regcache (tp
);
1578 struct gdbarch
*gdbarch
= regcache
->arch ();
1579 displaced_step_inferior_state
*displaced_state
1580 = get_displaced_stepping_state (tp
->inf
);
1582 return (((can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
1583 && target_is_non_stop_p ())
1584 || can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1585 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1586 && find_record_target () == NULL
1587 && !displaced_state
->failed_before
);
1590 /* Clean out any stray displaced stepping state. */
1592 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1594 /* Indicate that there is no cleanup pending. */
1595 displaced
->step_thread
= nullptr;
1597 delete displaced
->step_closure
;
1598 displaced
->step_closure
= NULL
;
1601 /* A cleanup that wraps displaced_step_clear. */
1602 using displaced_step_clear_cleanup
1603 = FORWARD_SCOPE_EXIT (displaced_step_clear
);
1605 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1607 displaced_step_dump_bytes (struct ui_file
*file
,
1608 const gdb_byte
*buf
,
1613 for (i
= 0; i
< len
; i
++)
1614 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1615 fputs_unfiltered ("\n", file
);
1618 /* Prepare to single-step, using displaced stepping.
1620 Note that we cannot use displaced stepping when we have a signal to
1621 deliver. If we have a signal to deliver and an instruction to step
1622 over, then after the step, there will be no indication from the
1623 target whether the thread entered a signal handler or ignored the
1624 signal and stepped over the instruction successfully --- both cases
1625 result in a simple SIGTRAP. In the first case we mustn't do a
1626 fixup, and in the second case we must --- but we can't tell which.
1627 Comments in the code for 'random signals' in handle_inferior_event
1628 explain how we handle this case instead.
1630 Returns 1 if preparing was successful -- this thread is going to be
1631 stepped now; 0 if displaced stepping this thread got queued; or -1
1632 if this instruction can't be displaced stepped. */
1635 displaced_step_prepare_throw (thread_info
*tp
)
1637 regcache
*regcache
= get_thread_regcache (tp
);
1638 struct gdbarch
*gdbarch
= regcache
->arch ();
1639 const address_space
*aspace
= regcache
->aspace ();
1640 CORE_ADDR original
, copy
;
1642 struct displaced_step_closure
*closure
;
1645 /* We should never reach this function if the architecture does not
1646 support displaced stepping. */
1647 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1649 /* Nor if the thread isn't meant to step over a breakpoint. */
1650 gdb_assert (tp
->control
.trap_expected
);
1652 /* Disable range stepping while executing in the scratch pad. We
1653 want a single-step even if executing the displaced instruction in
1654 the scratch buffer lands within the stepping range (e.g., a
1656 tp
->control
.may_range_step
= 0;
1658 /* We have to displaced step one thread at a time, as we only have
1659 access to a single scratch space per inferior. */
1661 displaced_step_inferior_state
*displaced
1662 = get_displaced_stepping_state (tp
->inf
);
1664 if (displaced
->step_thread
!= nullptr)
1666 /* Already waiting for a displaced step to finish. Defer this
1667 request and place in queue. */
1669 if (debug_displaced
)
1670 fprintf_unfiltered (gdb_stdlog
,
1671 "displaced: deferring step of %s\n",
1672 target_pid_to_str (tp
->ptid
).c_str ());
1674 thread_step_over_chain_enqueue (tp
);
1679 if (debug_displaced
)
1680 fprintf_unfiltered (gdb_stdlog
,
1681 "displaced: stepping %s now\n",
1682 target_pid_to_str (tp
->ptid
).c_str ());
1685 displaced_step_clear (displaced
);
1687 scoped_restore_current_thread restore_thread
;
1689 switch_to_thread (tp
);
1691 original
= regcache_read_pc (regcache
);
1693 copy
= gdbarch_displaced_step_location (gdbarch
);
1694 len
= gdbarch_max_insn_length (gdbarch
);
1696 if (breakpoint_in_range_p (aspace
, copy
, len
))
1698 /* There's a breakpoint set in the scratch pad location range
1699 (which is usually around the entry point). We'd either
1700 install it before resuming, which would overwrite/corrupt the
1701 scratch pad, or if it was already inserted, this displaced
1702 step would overwrite it. The latter is OK in the sense that
1703 we already assume that no thread is going to execute the code
1704 in the scratch pad range (after initial startup) anyway, but
1705 the former is unacceptable. Simply punt and fallback to
1706 stepping over this breakpoint in-line. */
1707 if (debug_displaced
)
1709 fprintf_unfiltered (gdb_stdlog
,
1710 "displaced: breakpoint set in scratch pad. "
1711 "Stepping over breakpoint in-line instead.\n");
1717 /* Save the original contents of the copy area. */
1718 displaced
->step_saved_copy
.resize (len
);
1719 status
= target_read_memory (copy
, displaced
->step_saved_copy
.data (), len
);
1721 throw_error (MEMORY_ERROR
,
1722 _("Error accessing memory address %s (%s) for "
1723 "displaced-stepping scratch space."),
1724 paddress (gdbarch
, copy
), safe_strerror (status
));
1725 if (debug_displaced
)
1727 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1728 paddress (gdbarch
, copy
));
1729 displaced_step_dump_bytes (gdb_stdlog
,
1730 displaced
->step_saved_copy
.data (),
1734 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1735 original
, copy
, regcache
);
1736 if (closure
== NULL
)
1738 /* The architecture doesn't know how or want to displaced step
1739 this instruction or instruction sequence. Fallback to
1740 stepping over the breakpoint in-line. */
1744 /* Save the information we need to fix things up if the step
1746 displaced
->step_thread
= tp
;
1747 displaced
->step_gdbarch
= gdbarch
;
1748 displaced
->step_closure
= closure
;
1749 displaced
->step_original
= original
;
1750 displaced
->step_copy
= copy
;
1753 displaced_step_clear_cleanup
cleanup (displaced
);
1755 /* Resume execution at the copy. */
1756 regcache_write_pc (regcache
, copy
);
1761 if (debug_displaced
)
1762 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1763 paddress (gdbarch
, copy
));
1768 /* Wrapper for displaced_step_prepare_throw that disabled further
1769 attempts at displaced stepping if we get a memory error. */
1772 displaced_step_prepare (thread_info
*thread
)
1778 prepared
= displaced_step_prepare_throw (thread
);
1780 catch (const gdb_exception_error
&ex
)
1782 struct displaced_step_inferior_state
*displaced_state
;
1784 if (ex
.error
!= MEMORY_ERROR
1785 && ex
.error
!= NOT_SUPPORTED_ERROR
)
1790 fprintf_unfiltered (gdb_stdlog
,
1791 "infrun: disabling displaced stepping: %s\n",
1795 /* Be verbose if "set displaced-stepping" is "on", silent if
1797 if (can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1799 warning (_("disabling displaced stepping: %s"),
1803 /* Disable further displaced stepping attempts. */
1805 = get_displaced_stepping_state (thread
->inf
);
1806 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 (const gdb_exception
&ex
)
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 ());
2633 /* Counter that tracks number of user visible stops. This can be used
2634 to tell whether a command has proceeded the inferior past the
2635 current location. This allows e.g., inferior function calls in
2636 breakpoint commands to not interrupt the command list. When the
2637 call finishes successfully, the inferior is standing at the same
2638 breakpoint as if nothing happened (and so we don't call
2640 static ULONGEST current_stop_id
;
2647 return current_stop_id
;
2650 /* Called when we report a user visible stop. */
2658 /* Clear out all variables saying what to do when inferior is continued.
2659 First do this, then set the ones you want, then call `proceed'. */
2662 clear_proceed_status_thread (struct thread_info
*tp
)
2665 fprintf_unfiltered (gdb_stdlog
,
2666 "infrun: clear_proceed_status_thread (%s)\n",
2667 target_pid_to_str (tp
->ptid
).c_str ());
2669 /* If we're starting a new sequence, then the previous finished
2670 single-step is no longer relevant. */
2671 if (tp
->suspend
.waitstatus_pending_p
)
2673 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
2676 fprintf_unfiltered (gdb_stdlog
,
2677 "infrun: clear_proceed_status: pending "
2678 "event of %s was a finished step. "
2680 target_pid_to_str (tp
->ptid
).c_str ());
2682 tp
->suspend
.waitstatus_pending_p
= 0;
2683 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2685 else if (debug_infrun
)
2688 = target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2690 fprintf_unfiltered (gdb_stdlog
,
2691 "infrun: clear_proceed_status_thread: thread %s "
2692 "has pending wait status %s "
2693 "(currently_stepping=%d).\n",
2694 target_pid_to_str (tp
->ptid
).c_str (),
2696 currently_stepping (tp
));
2700 /* If this signal should not be seen by program, give it zero.
2701 Used for debugging signals. */
2702 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2703 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2705 delete tp
->thread_fsm
;
2706 tp
->thread_fsm
= NULL
;
2708 tp
->control
.trap_expected
= 0;
2709 tp
->control
.step_range_start
= 0;
2710 tp
->control
.step_range_end
= 0;
2711 tp
->control
.may_range_step
= 0;
2712 tp
->control
.step_frame_id
= null_frame_id
;
2713 tp
->control
.step_stack_frame_id
= null_frame_id
;
2714 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2715 tp
->control
.step_start_function
= NULL
;
2716 tp
->stop_requested
= 0;
2718 tp
->control
.stop_step
= 0;
2720 tp
->control
.proceed_to_finish
= 0;
2722 tp
->control
.stepping_command
= 0;
2724 /* Discard any remaining commands or status from previous stop. */
2725 bpstat_clear (&tp
->control
.stop_bpstat
);
2729 clear_proceed_status (int step
)
2731 /* With scheduler-locking replay, stop replaying other threads if we're
2732 not replaying the user-visible resume ptid.
2734 This is a convenience feature to not require the user to explicitly
2735 stop replaying the other threads. We're assuming that the user's
2736 intent is to resume tracing the recorded process. */
2737 if (!non_stop
&& scheduler_mode
== schedlock_replay
2738 && target_record_is_replaying (minus_one_ptid
)
2739 && !target_record_will_replay (user_visible_resume_ptid (step
),
2740 execution_direction
))
2741 target_record_stop_replaying ();
2743 if (!non_stop
&& inferior_ptid
!= null_ptid
)
2745 ptid_t resume_ptid
= user_visible_resume_ptid (step
);
2747 /* In all-stop mode, delete the per-thread status of all threads
2748 we're about to resume, implicitly and explicitly. */
2749 for (thread_info
*tp
: all_non_exited_threads (resume_ptid
))
2750 clear_proceed_status_thread (tp
);
2753 if (inferior_ptid
!= null_ptid
)
2755 struct inferior
*inferior
;
2759 /* If in non-stop mode, only delete the per-thread status of
2760 the current thread. */
2761 clear_proceed_status_thread (inferior_thread ());
2764 inferior
= current_inferior ();
2765 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2768 gdb::observers::about_to_proceed
.notify ();
2771 /* Returns true if TP is still stopped at a breakpoint that needs
2772 stepping-over in order to make progress. If the breakpoint is gone
2773 meanwhile, we can skip the whole step-over dance. */
2776 thread_still_needs_step_over_bp (struct thread_info
*tp
)
2778 if (tp
->stepping_over_breakpoint
)
2780 struct regcache
*regcache
= get_thread_regcache (tp
);
2782 if (breakpoint_here_p (regcache
->aspace (),
2783 regcache_read_pc (regcache
))
2784 == ordinary_breakpoint_here
)
2787 tp
->stepping_over_breakpoint
= 0;
2793 /* Check whether thread TP still needs to start a step-over in order
2794 to make progress when resumed. Returns an bitwise or of enum
2795 step_over_what bits, indicating what needs to be stepped over. */
2797 static step_over_what
2798 thread_still_needs_step_over (struct thread_info
*tp
)
2800 step_over_what what
= 0;
2802 if (thread_still_needs_step_over_bp (tp
))
2803 what
|= STEP_OVER_BREAKPOINT
;
2805 if (tp
->stepping_over_watchpoint
2806 && !target_have_steppable_watchpoint
)
2807 what
|= STEP_OVER_WATCHPOINT
;
2812 /* Returns true if scheduler locking applies. STEP indicates whether
2813 we're about to do a step/next-like command to a thread. */
2816 schedlock_applies (struct thread_info
*tp
)
2818 return (scheduler_mode
== schedlock_on
2819 || (scheduler_mode
== schedlock_step
2820 && tp
->control
.stepping_command
)
2821 || (scheduler_mode
== schedlock_replay
2822 && target_record_will_replay (minus_one_ptid
,
2823 execution_direction
)));
2826 /* Basic routine for continuing the program in various fashions.
2828 ADDR is the address to resume at, or -1 for resume where stopped.
2829 SIGGNAL is the signal to give it, or GDB_SIGNAL_0 for none,
2830 or GDB_SIGNAL_DEFAULT for act according to how it stopped.
2832 You should call clear_proceed_status before calling proceed. */
2835 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
)
2837 struct regcache
*regcache
;
2838 struct gdbarch
*gdbarch
;
2841 struct execution_control_state ecss
;
2842 struct execution_control_state
*ecs
= &ecss
;
2845 /* If we're stopped at a fork/vfork, follow the branch set by the
2846 "set follow-fork-mode" command; otherwise, we'll just proceed
2847 resuming the current thread. */
2848 if (!follow_fork ())
2850 /* The target for some reason decided not to resume. */
2852 if (target_can_async_p ())
2853 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2857 /* We'll update this if & when we switch to a new thread. */
2858 previous_inferior_ptid
= inferior_ptid
;
2860 regcache
= get_current_regcache ();
2861 gdbarch
= regcache
->arch ();
2862 const address_space
*aspace
= regcache
->aspace ();
2864 pc
= regcache_read_pc (regcache
);
2865 thread_info
*cur_thr
= inferior_thread ();
2867 /* Fill in with reasonable starting values. */
2868 init_thread_stepping_state (cur_thr
);
2870 gdb_assert (!thread_is_in_step_over_chain (cur_thr
));
2872 if (addr
== (CORE_ADDR
) -1)
2874 if (pc
== cur_thr
->suspend
.stop_pc
2875 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
2876 && execution_direction
!= EXEC_REVERSE
)
2877 /* There is a breakpoint at the address we will resume at,
2878 step one instruction before inserting breakpoints so that
2879 we do not stop right away (and report a second hit at this
2882 Note, we don't do this in reverse, because we won't
2883 actually be executing the breakpoint insn anyway.
2884 We'll be (un-)executing the previous instruction. */
2885 cur_thr
->stepping_over_breakpoint
= 1;
2886 else if (gdbarch_single_step_through_delay_p (gdbarch
)
2887 && gdbarch_single_step_through_delay (gdbarch
,
2888 get_current_frame ()))
2889 /* We stepped onto an instruction that needs to be stepped
2890 again before re-inserting the breakpoint, do so. */
2891 cur_thr
->stepping_over_breakpoint
= 1;
2895 regcache_write_pc (regcache
, addr
);
2898 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
2899 cur_thr
->suspend
.stop_signal
= siggnal
;
2901 resume_ptid
= user_visible_resume_ptid (cur_thr
->control
.stepping_command
);
2903 /* If an exception is thrown from this point on, make sure to
2904 propagate GDB's knowledge of the executing state to the
2905 frontend/user running state. */
2906 scoped_finish_thread_state
finish_state (resume_ptid
);
2908 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
2909 threads (e.g., we might need to set threads stepping over
2910 breakpoints first), from the user/frontend's point of view, all
2911 threads in RESUME_PTID are now running. Unless we're calling an
2912 inferior function, as in that case we pretend the inferior
2913 doesn't run at all. */
2914 if (!cur_thr
->control
.in_infcall
)
2915 set_running (resume_ptid
, 1);
2918 fprintf_unfiltered (gdb_stdlog
,
2919 "infrun: proceed (addr=%s, signal=%s)\n",
2920 paddress (gdbarch
, addr
),
2921 gdb_signal_to_symbol_string (siggnal
));
2923 annotate_starting ();
2925 /* Make sure that output from GDB appears before output from the
2927 gdb_flush (gdb_stdout
);
2929 /* Since we've marked the inferior running, give it the terminal. A
2930 QUIT/Ctrl-C from here on is forwarded to the target (which can
2931 still detect attempts to unblock a stuck connection with repeated
2932 Ctrl-C from within target_pass_ctrlc). */
2933 target_terminal::inferior ();
2935 /* In a multi-threaded task we may select another thread and
2936 then continue or step.
2938 But if a thread that we're resuming had stopped at a breakpoint,
2939 it will immediately cause another breakpoint stop without any
2940 execution (i.e. it will report a breakpoint hit incorrectly). So
2941 we must step over it first.
2943 Look for threads other than the current (TP) that reported a
2944 breakpoint hit and haven't been resumed yet since. */
2946 /* If scheduler locking applies, we can avoid iterating over all
2948 if (!non_stop
&& !schedlock_applies (cur_thr
))
2950 for (thread_info
*tp
: all_non_exited_threads (resume_ptid
))
2952 /* Ignore the current thread here. It's handled
2957 if (!thread_still_needs_step_over (tp
))
2960 gdb_assert (!thread_is_in_step_over_chain (tp
));
2963 fprintf_unfiltered (gdb_stdlog
,
2964 "infrun: need to step-over [%s] first\n",
2965 target_pid_to_str (tp
->ptid
).c_str ());
2967 thread_step_over_chain_enqueue (tp
);
2971 /* Enqueue the current thread last, so that we move all other
2972 threads over their breakpoints first. */
2973 if (cur_thr
->stepping_over_breakpoint
)
2974 thread_step_over_chain_enqueue (cur_thr
);
2976 /* If the thread isn't started, we'll still need to set its prev_pc,
2977 so that switch_back_to_stepped_thread knows the thread hasn't
2978 advanced. Must do this before resuming any thread, as in
2979 all-stop/remote, once we resume we can't send any other packet
2980 until the target stops again. */
2981 cur_thr
->prev_pc
= regcache_read_pc (regcache
);
2984 scoped_restore save_defer_tc
= make_scoped_defer_target_commit_resume ();
2986 started
= start_step_over ();
2988 if (step_over_info_valid_p ())
2990 /* Either this thread started a new in-line step over, or some
2991 other thread was already doing one. In either case, don't
2992 resume anything else until the step-over is finished. */
2994 else if (started
&& !target_is_non_stop_p ())
2996 /* A new displaced stepping sequence was started. In all-stop,
2997 we can't talk to the target anymore until it next stops. */
2999 else if (!non_stop
&& target_is_non_stop_p ())
3001 /* In all-stop, but the target is always in non-stop mode.
3002 Start all other threads that are implicitly resumed too. */
3003 for (thread_info
*tp
: all_non_exited_threads (resume_ptid
))
3008 fprintf_unfiltered (gdb_stdlog
,
3009 "infrun: proceed: [%s] resumed\n",
3010 target_pid_to_str (tp
->ptid
).c_str ());
3011 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
3015 if (thread_is_in_step_over_chain (tp
))
3018 fprintf_unfiltered (gdb_stdlog
,
3019 "infrun: proceed: [%s] needs step-over\n",
3020 target_pid_to_str (tp
->ptid
).c_str ());
3025 fprintf_unfiltered (gdb_stdlog
,
3026 "infrun: proceed: resuming %s\n",
3027 target_pid_to_str (tp
->ptid
).c_str ());
3029 reset_ecs (ecs
, tp
);
3030 switch_to_thread (tp
);
3031 keep_going_pass_signal (ecs
);
3032 if (!ecs
->wait_some_more
)
3033 error (_("Command aborted."));
3036 else if (!cur_thr
->resumed
&& !thread_is_in_step_over_chain (cur_thr
))
3038 /* The thread wasn't started, and isn't queued, run it now. */
3039 reset_ecs (ecs
, cur_thr
);
3040 switch_to_thread (cur_thr
);
3041 keep_going_pass_signal (ecs
);
3042 if (!ecs
->wait_some_more
)
3043 error (_("Command aborted."));
3047 target_commit_resume ();
3049 finish_state
.release ();
3051 /* Tell the event loop to wait for it to stop. If the target
3052 supports asynchronous execution, it'll do this from within
3054 if (!target_can_async_p ())
3055 mark_async_event_handler (infrun_async_inferior_event_token
);
3059 /* Start remote-debugging of a machine over a serial link. */
3062 start_remote (int from_tty
)
3064 struct inferior
*inferior
;
3066 inferior
= current_inferior ();
3067 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
3069 /* Always go on waiting for the target, regardless of the mode. */
3070 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3071 indicate to wait_for_inferior that a target should timeout if
3072 nothing is returned (instead of just blocking). Because of this,
3073 targets expecting an immediate response need to, internally, set
3074 things up so that the target_wait() is forced to eventually
3076 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3077 differentiate to its caller what the state of the target is after
3078 the initial open has been performed. Here we're assuming that
3079 the target has stopped. It should be possible to eventually have
3080 target_open() return to the caller an indication that the target
3081 is currently running and GDB state should be set to the same as
3082 for an async run. */
3083 wait_for_inferior ();
3085 /* Now that the inferior has stopped, do any bookkeeping like
3086 loading shared libraries. We want to do this before normal_stop,
3087 so that the displayed frame is up to date. */
3088 post_create_inferior (current_top_target (), from_tty
);
3093 /* Initialize static vars when a new inferior begins. */
3096 init_wait_for_inferior (void)
3098 /* These are meaningless until the first time through wait_for_inferior. */
3100 breakpoint_init_inferior (inf_starting
);
3102 clear_proceed_status (0);
3104 target_last_wait_ptid
= minus_one_ptid
;
3106 previous_inferior_ptid
= inferior_ptid
;
3111 static void handle_inferior_event (struct execution_control_state
*ecs
);
3113 static void handle_step_into_function (struct gdbarch
*gdbarch
,
3114 struct execution_control_state
*ecs
);
3115 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
3116 struct execution_control_state
*ecs
);
3117 static void handle_signal_stop (struct execution_control_state
*ecs
);
3118 static void check_exception_resume (struct execution_control_state
*,
3119 struct frame_info
*);
3121 static void end_stepping_range (struct execution_control_state
*ecs
);
3122 static void stop_waiting (struct execution_control_state
*ecs
);
3123 static void keep_going (struct execution_control_state
*ecs
);
3124 static void process_event_stop_test (struct execution_control_state
*ecs
);
3125 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
3127 /* This function is attached as a "thread_stop_requested" observer.
3128 Cleanup local state that assumed the PTID was to be resumed, and
3129 report the stop to the frontend. */
3132 infrun_thread_stop_requested (ptid_t ptid
)
3134 /* PTID was requested to stop. If the thread was already stopped,
3135 but the user/frontend doesn't know about that yet (e.g., the
3136 thread had been temporarily paused for some step-over), set up
3137 for reporting the stop now. */
3138 for (thread_info
*tp
: all_threads (ptid
))
3140 if (tp
->state
!= THREAD_RUNNING
)
3145 /* Remove matching threads from the step-over queue, so
3146 start_step_over doesn't try to resume them
3148 if (thread_is_in_step_over_chain (tp
))
3149 thread_step_over_chain_remove (tp
);
3151 /* If the thread is stopped, but the user/frontend doesn't
3152 know about that yet, queue a pending event, as if the
3153 thread had just stopped now. Unless the thread already had
3155 if (!tp
->suspend
.waitstatus_pending_p
)
3157 tp
->suspend
.waitstatus_pending_p
= 1;
3158 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_STOPPED
;
3159 tp
->suspend
.waitstatus
.value
.sig
= GDB_SIGNAL_0
;
3162 /* Clear the inline-frame state, since we're re-processing the
3164 clear_inline_frame_state (tp
->ptid
);
3166 /* If this thread was paused because some other thread was
3167 doing an inline-step over, let that finish first. Once
3168 that happens, we'll restart all threads and consume pending
3169 stop events then. */
3170 if (step_over_info_valid_p ())
3173 /* Otherwise we can process the (new) pending event now. Set
3174 it so this pending event is considered by
3181 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
3183 if (target_last_wait_ptid
== tp
->ptid
)
3184 nullify_last_target_wait_ptid ();
3187 /* Delete the step resume, single-step and longjmp/exception resume
3188 breakpoints of TP. */
3191 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
3193 delete_step_resume_breakpoint (tp
);
3194 delete_exception_resume_breakpoint (tp
);
3195 delete_single_step_breakpoints (tp
);
3198 /* If the target still has execution, call FUNC for each thread that
3199 just stopped. In all-stop, that's all the non-exited threads; in
3200 non-stop, that's the current thread, only. */
3202 typedef void (*for_each_just_stopped_thread_callback_func
)
3203 (struct thread_info
*tp
);
3206 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
3208 if (!target_has_execution
|| inferior_ptid
== null_ptid
)
3211 if (target_is_non_stop_p ())
3213 /* If in non-stop mode, only the current thread stopped. */
3214 func (inferior_thread ());
3218 /* In all-stop mode, all threads have stopped. */
3219 for (thread_info
*tp
: all_non_exited_threads ())
3224 /* Delete the step resume and longjmp/exception resume breakpoints of
3225 the threads that just stopped. */
3228 delete_just_stopped_threads_infrun_breakpoints (void)
3230 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3233 /* Delete the single-step breakpoints of the threads that just
3237 delete_just_stopped_threads_single_step_breakpoints (void)
3239 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3245 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3246 const struct target_waitstatus
*ws
)
3248 std::string status_string
= target_waitstatus_to_string (ws
);
3251 /* The text is split over several lines because it was getting too long.
3252 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3253 output as a unit; we want only one timestamp printed if debug_timestamp
3256 stb
.printf ("infrun: target_wait (%d.%ld.%ld",
3259 waiton_ptid
.tid ());
3260 if (waiton_ptid
.pid () != -1)
3261 stb
.printf (" [%s]", target_pid_to_str (waiton_ptid
).c_str ());
3262 stb
.printf (", status) =\n");
3263 stb
.printf ("infrun: %d.%ld.%ld [%s],\n",
3267 target_pid_to_str (result_ptid
).c_str ());
3268 stb
.printf ("infrun: %s\n", status_string
.c_str ());
3270 /* This uses %s in part to handle %'s in the text, but also to avoid
3271 a gcc error: the format attribute requires a string literal. */
3272 fprintf_unfiltered (gdb_stdlog
, "%s", stb
.c_str ());
3275 /* Select a thread at random, out of those which are resumed and have
3278 static struct thread_info
*
3279 random_pending_event_thread (ptid_t waiton_ptid
)
3283 auto has_event
= [] (thread_info
*tp
)
3286 && tp
->suspend
.waitstatus_pending_p
);
3289 /* First see how many events we have. Count only resumed threads
3290 that have an event pending. */
3291 for (thread_info
*tp
: all_non_exited_threads (waiton_ptid
))
3295 if (num_events
== 0)
3298 /* Now randomly pick a thread out of those that have had events. */
3299 int random_selector
= (int) ((num_events
* (double) rand ())
3300 / (RAND_MAX
+ 1.0));
3302 if (debug_infrun
&& num_events
> 1)
3303 fprintf_unfiltered (gdb_stdlog
,
3304 "infrun: Found %d events, selecting #%d\n",
3305 num_events
, random_selector
);
3307 /* Select the Nth thread that has had an event. */
3308 for (thread_info
*tp
: all_non_exited_threads (waiton_ptid
))
3310 if (random_selector
-- == 0)
3313 gdb_assert_not_reached ("event thread not found");
3316 /* Wrapper for target_wait that first checks whether threads have
3317 pending statuses to report before actually asking the target for
3321 do_target_wait (ptid_t ptid
, struct target_waitstatus
*status
, int options
)
3324 struct thread_info
*tp
;
3326 /* First check if there is a resumed thread with a wait status
3328 if (ptid
== minus_one_ptid
|| ptid
.is_pid ())
3330 tp
= random_pending_event_thread (ptid
);
3335 fprintf_unfiltered (gdb_stdlog
,
3336 "infrun: Waiting for specific thread %s.\n",
3337 target_pid_to_str (ptid
).c_str ());
3339 /* We have a specific thread to check. */
3340 tp
= find_thread_ptid (ptid
);
3341 gdb_assert (tp
!= NULL
);
3342 if (!tp
->suspend
.waitstatus_pending_p
)
3347 && (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3348 || tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
3350 struct regcache
*regcache
= get_thread_regcache (tp
);
3351 struct gdbarch
*gdbarch
= regcache
->arch ();
3355 pc
= regcache_read_pc (regcache
);
3357 if (pc
!= tp
->suspend
.stop_pc
)
3360 fprintf_unfiltered (gdb_stdlog
,
3361 "infrun: PC of %s changed. was=%s, now=%s\n",
3362 target_pid_to_str (tp
->ptid
).c_str (),
3363 paddress (gdbarch
, tp
->suspend
.stop_pc
),
3364 paddress (gdbarch
, pc
));
3367 else if (!breakpoint_inserted_here_p (regcache
->aspace (), pc
))
3370 fprintf_unfiltered (gdb_stdlog
,
3371 "infrun: previous breakpoint of %s, at %s gone\n",
3372 target_pid_to_str (tp
->ptid
).c_str (),
3373 paddress (gdbarch
, pc
));
3381 fprintf_unfiltered (gdb_stdlog
,
3382 "infrun: pending event of %s cancelled.\n",
3383 target_pid_to_str (tp
->ptid
).c_str ());
3385 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_SPURIOUS
;
3386 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3395 = target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
3397 fprintf_unfiltered (gdb_stdlog
,
3398 "infrun: Using pending wait status %s for %s.\n",
3400 target_pid_to_str (tp
->ptid
).c_str ());
3403 /* Now that we've selected our final event LWP, un-adjust its PC
3404 if it was a software breakpoint (and the target doesn't
3405 always adjust the PC itself). */
3406 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3407 && !target_supports_stopped_by_sw_breakpoint ())
3409 struct regcache
*regcache
;
3410 struct gdbarch
*gdbarch
;
3413 regcache
= get_thread_regcache (tp
);
3414 gdbarch
= regcache
->arch ();
3416 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3421 pc
= regcache_read_pc (regcache
);
3422 regcache_write_pc (regcache
, pc
+ decr_pc
);
3426 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3427 *status
= tp
->suspend
.waitstatus
;
3428 tp
->suspend
.waitstatus_pending_p
= 0;
3430 /* Wake up the event loop again, until all pending events are
3432 if (target_is_async_p ())
3433 mark_async_event_handler (infrun_async_inferior_event_token
);
3437 /* But if we don't find one, we'll have to wait. */
3439 if (deprecated_target_wait_hook
)
3440 event_ptid
= deprecated_target_wait_hook (ptid
, status
, options
);
3442 event_ptid
= target_wait (ptid
, status
, options
);
3447 /* Prepare and stabilize the inferior for detaching it. E.g.,
3448 detaching while a thread is displaced stepping is a recipe for
3449 crashing it, as nothing would readjust the PC out of the scratch
3453 prepare_for_detach (void)
3455 struct inferior
*inf
= current_inferior ();
3456 ptid_t pid_ptid
= ptid_t (inf
->pid
);
3458 displaced_step_inferior_state
*displaced
= get_displaced_stepping_state (inf
);
3460 /* Is any thread of this process displaced stepping? If not,
3461 there's nothing else to do. */
3462 if (displaced
->step_thread
== nullptr)
3466 fprintf_unfiltered (gdb_stdlog
,
3467 "displaced-stepping in-process while detaching");
3469 scoped_restore restore_detaching
= make_scoped_restore (&inf
->detaching
, true);
3471 while (displaced
->step_thread
!= nullptr)
3473 struct execution_control_state ecss
;
3474 struct execution_control_state
*ecs
;
3477 memset (ecs
, 0, sizeof (*ecs
));
3479 overlay_cache_invalid
= 1;
3480 /* Flush target cache before starting to handle each event.
3481 Target was running and cache could be stale. This is just a
3482 heuristic. Running threads may modify target memory, but we
3483 don't get any event. */
3484 target_dcache_invalidate ();
3486 ecs
->ptid
= do_target_wait (pid_ptid
, &ecs
->ws
, 0);
3489 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
3491 /* If an error happens while handling the event, propagate GDB's
3492 knowledge of the executing state to the frontend/user running
3494 scoped_finish_thread_state
finish_state (minus_one_ptid
);
3496 /* Now figure out what to do with the result of the result. */
3497 handle_inferior_event (ecs
);
3499 /* No error, don't finish the state yet. */
3500 finish_state
.release ();
3502 /* Breakpoints and watchpoints are not installed on the target
3503 at this point, and signals are passed directly to the
3504 inferior, so this must mean the process is gone. */
3505 if (!ecs
->wait_some_more
)
3507 restore_detaching
.release ();
3508 error (_("Program exited while detaching"));
3512 restore_detaching
.release ();
3515 /* Wait for control to return from inferior to debugger.
3517 If inferior gets a signal, we may decide to start it up again
3518 instead of returning. That is why there is a loop in this function.
3519 When this function actually returns it means the inferior
3520 should be left stopped and GDB should read more commands. */
3523 wait_for_inferior (void)
3527 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
3529 SCOPE_EXIT
{ delete_just_stopped_threads_infrun_breakpoints (); };
3531 /* If an error happens while handling the event, propagate GDB's
3532 knowledge of the executing state to the frontend/user running
3534 scoped_finish_thread_state
finish_state (minus_one_ptid
);
3538 struct execution_control_state ecss
;
3539 struct execution_control_state
*ecs
= &ecss
;
3540 ptid_t waiton_ptid
= minus_one_ptid
;
3542 memset (ecs
, 0, sizeof (*ecs
));
3544 overlay_cache_invalid
= 1;
3546 /* Flush target cache before starting to handle each event.
3547 Target was running and cache could be stale. This is just a
3548 heuristic. Running threads may modify target memory, but we
3549 don't get any event. */
3550 target_dcache_invalidate ();
3552 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
, 0);
3555 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3557 /* Now figure out what to do with the result of the result. */
3558 handle_inferior_event (ecs
);
3560 if (!ecs
->wait_some_more
)
3564 /* No error, don't finish the state yet. */
3565 finish_state
.release ();
3568 /* Cleanup that reinstalls the readline callback handler, if the
3569 target is running in the background. If while handling the target
3570 event something triggered a secondary prompt, like e.g., a
3571 pagination prompt, we'll have removed the callback handler (see
3572 gdb_readline_wrapper_line). Need to do this as we go back to the
3573 event loop, ready to process further input. Note this has no
3574 effect if the handler hasn't actually been removed, because calling
3575 rl_callback_handler_install resets the line buffer, thus losing
3579 reinstall_readline_callback_handler_cleanup ()
3581 struct ui
*ui
= current_ui
;
3585 /* We're not going back to the top level event loop yet. Don't
3586 install the readline callback, as it'd prep the terminal,
3587 readline-style (raw, noecho) (e.g., --batch). We'll install
3588 it the next time the prompt is displayed, when we're ready
3593 if (ui
->command_editing
&& ui
->prompt_state
!= PROMPT_BLOCKED
)
3594 gdb_rl_callback_handler_reinstall ();
3597 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3598 that's just the event thread. In all-stop, that's all threads. */
3601 clean_up_just_stopped_threads_fsms (struct execution_control_state
*ecs
)
3603 if (ecs
->event_thread
!= NULL
3604 && ecs
->event_thread
->thread_fsm
!= NULL
)
3605 ecs
->event_thread
->thread_fsm
->clean_up (ecs
->event_thread
);
3609 for (thread_info
*thr
: all_non_exited_threads ())
3611 if (thr
->thread_fsm
== NULL
)
3613 if (thr
== ecs
->event_thread
)
3616 switch_to_thread (thr
);
3617 thr
->thread_fsm
->clean_up (thr
);
3620 if (ecs
->event_thread
!= NULL
)
3621 switch_to_thread (ecs
->event_thread
);
3625 /* Helper for all_uis_check_sync_execution_done that works on the
3629 check_curr_ui_sync_execution_done (void)
3631 struct ui
*ui
= current_ui
;
3633 if (ui
->prompt_state
== PROMPT_NEEDED
3635 && !gdb_in_secondary_prompt_p (ui
))
3637 target_terminal::ours ();
3638 gdb::observers::sync_execution_done
.notify ();
3639 ui_register_input_event_handler (ui
);
3646 all_uis_check_sync_execution_done (void)
3648 SWITCH_THRU_ALL_UIS ()
3650 check_curr_ui_sync_execution_done ();
3657 all_uis_on_sync_execution_starting (void)
3659 SWITCH_THRU_ALL_UIS ()
3661 if (current_ui
->prompt_state
== PROMPT_NEEDED
)
3662 async_disable_stdin ();
3666 /* Asynchronous version of wait_for_inferior. It is called by the
3667 event loop whenever a change of state is detected on the file
3668 descriptor corresponding to the target. It can be called more than
3669 once to complete a single execution command. In such cases we need
3670 to keep the state in a global variable ECSS. If it is the last time
3671 that this function is called for a single execution command, then
3672 report to the user that the inferior has stopped, and do the
3673 necessary cleanups. */
3676 fetch_inferior_event (void *client_data
)
3678 struct execution_control_state ecss
;
3679 struct execution_control_state
*ecs
= &ecss
;
3681 ptid_t waiton_ptid
= minus_one_ptid
;
3683 memset (ecs
, 0, sizeof (*ecs
));
3685 /* Events are always processed with the main UI as current UI. This
3686 way, warnings, debug output, etc. are always consistently sent to
3687 the main console. */
3688 scoped_restore save_ui
= make_scoped_restore (¤t_ui
, main_ui
);
3690 /* End up with readline processing input, if necessary. */
3692 SCOPE_EXIT
{ reinstall_readline_callback_handler_cleanup (); };
3694 /* We're handling a live event, so make sure we're doing live
3695 debugging. If we're looking at traceframes while the target is
3696 running, we're going to need to get back to that mode after
3697 handling the event. */
3698 gdb::optional
<scoped_restore_current_traceframe
> maybe_restore_traceframe
;
3701 maybe_restore_traceframe
.emplace ();
3702 set_current_traceframe (-1);
3705 gdb::optional
<scoped_restore_current_thread
> maybe_restore_thread
;
3708 /* In non-stop mode, the user/frontend should not notice a thread
3709 switch due to internal events. Make sure we reverse to the
3710 user selected thread and frame after handling the event and
3711 running any breakpoint commands. */
3712 maybe_restore_thread
.emplace ();
3714 overlay_cache_invalid
= 1;
3715 /* Flush target cache before starting to handle each event. Target
3716 was running and cache could be stale. This is just a heuristic.
3717 Running threads may modify target memory, but we don't get any
3719 target_dcache_invalidate ();
3721 scoped_restore save_exec_dir
3722 = make_scoped_restore (&execution_direction
,
3723 target_execution_direction ());
3725 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
,
3726 target_can_async_p () ? TARGET_WNOHANG
: 0);
3729 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3731 /* If an error happens while handling the event, propagate GDB's
3732 knowledge of the executing state to the frontend/user running
3734 ptid_t finish_ptid
= !target_is_non_stop_p () ? minus_one_ptid
: ecs
->ptid
;
3735 scoped_finish_thread_state
finish_state (finish_ptid
);
3737 /* Get executed before scoped_restore_current_thread above to apply
3738 still for the thread which has thrown the exception. */
3739 auto defer_bpstat_clear
3740 = make_scope_exit (bpstat_clear_actions
);
3741 auto defer_delete_threads
3742 = make_scope_exit (delete_just_stopped_threads_infrun_breakpoints
);
3744 /* Now figure out what to do with the result of the result. */
3745 handle_inferior_event (ecs
);
3747 if (!ecs
->wait_some_more
)
3749 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
3750 int should_stop
= 1;
3751 struct thread_info
*thr
= ecs
->event_thread
;
3753 delete_just_stopped_threads_infrun_breakpoints ();
3757 struct thread_fsm
*thread_fsm
= thr
->thread_fsm
;
3759 if (thread_fsm
!= NULL
)
3760 should_stop
= thread_fsm
->should_stop (thr
);
3769 bool should_notify_stop
= true;
3772 clean_up_just_stopped_threads_fsms (ecs
);
3774 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3775 should_notify_stop
= thr
->thread_fsm
->should_notify_stop ();
3777 if (should_notify_stop
)
3779 /* We may not find an inferior if this was a process exit. */
3780 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
3781 proceeded
= normal_stop ();
3786 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3792 defer_delete_threads
.release ();
3793 defer_bpstat_clear
.release ();
3795 /* No error, don't finish the thread states yet. */
3796 finish_state
.release ();
3798 /* This scope is used to ensure that readline callbacks are
3799 reinstalled here. */
3802 /* If a UI was in sync execution mode, and now isn't, restore its
3803 prompt (a synchronous execution command has finished, and we're
3804 ready for input). */
3805 all_uis_check_sync_execution_done ();
3808 && exec_done_display_p
3809 && (inferior_ptid
== null_ptid
3810 || inferior_thread ()->state
!= THREAD_RUNNING
))
3811 printf_unfiltered (_("completed.\n"));
3814 /* Record the frame and location we're currently stepping through. */
3816 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
3818 struct thread_info
*tp
= inferior_thread ();
3820 tp
->control
.step_frame_id
= get_frame_id (frame
);
3821 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
3823 tp
->current_symtab
= sal
.symtab
;
3824 tp
->current_line
= sal
.line
;
3827 /* Clear context switchable stepping state. */
3830 init_thread_stepping_state (struct thread_info
*tss
)
3832 tss
->stepped_breakpoint
= 0;
3833 tss
->stepping_over_breakpoint
= 0;
3834 tss
->stepping_over_watchpoint
= 0;
3835 tss
->step_after_step_resume_breakpoint
= 0;
3838 /* Set the cached copy of the last ptid/waitstatus. */
3841 set_last_target_status (ptid_t ptid
, struct target_waitstatus status
)
3843 target_last_wait_ptid
= ptid
;
3844 target_last_waitstatus
= status
;
3847 /* Return the cached copy of the last pid/waitstatus returned by
3848 target_wait()/deprecated_target_wait_hook(). The data is actually
3849 cached by handle_inferior_event(), which gets called immediately
3850 after target_wait()/deprecated_target_wait_hook(). */
3853 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
3855 *ptidp
= target_last_wait_ptid
;
3856 *status
= target_last_waitstatus
;
3860 nullify_last_target_wait_ptid (void)
3862 target_last_wait_ptid
= minus_one_ptid
;
3865 /* Switch thread contexts. */
3868 context_switch (execution_control_state
*ecs
)
3871 && ecs
->ptid
!= inferior_ptid
3872 && ecs
->event_thread
!= inferior_thread ())
3874 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
3875 target_pid_to_str (inferior_ptid
).c_str ());
3876 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
3877 target_pid_to_str (ecs
->ptid
).c_str ());
3880 switch_to_thread (ecs
->event_thread
);
3883 /* If the target can't tell whether we've hit breakpoints
3884 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
3885 check whether that could have been caused by a breakpoint. If so,
3886 adjust the PC, per gdbarch_decr_pc_after_break. */
3889 adjust_pc_after_break (struct thread_info
*thread
,
3890 struct target_waitstatus
*ws
)
3892 struct regcache
*regcache
;
3893 struct gdbarch
*gdbarch
;
3894 CORE_ADDR breakpoint_pc
, decr_pc
;
3896 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
3897 we aren't, just return.
3899 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
3900 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
3901 implemented by software breakpoints should be handled through the normal
3904 NOTE drow/2004-01-31: On some targets, breakpoints may generate
3905 different signals (SIGILL or SIGEMT for instance), but it is less
3906 clear where the PC is pointing afterwards. It may not match
3907 gdbarch_decr_pc_after_break. I don't know any specific target that
3908 generates these signals at breakpoints (the code has been in GDB since at
3909 least 1992) so I can not guess how to handle them here.
3911 In earlier versions of GDB, a target with
3912 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
3913 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
3914 target with both of these set in GDB history, and it seems unlikely to be
3915 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
3917 if (ws
->kind
!= TARGET_WAITKIND_STOPPED
)
3920 if (ws
->value
.sig
!= GDB_SIGNAL_TRAP
)
3923 /* In reverse execution, when a breakpoint is hit, the instruction
3924 under it has already been de-executed. The reported PC always
3925 points at the breakpoint address, so adjusting it further would
3926 be wrong. E.g., consider this case on a decr_pc_after_break == 1
3929 B1 0x08000000 : INSN1
3930 B2 0x08000001 : INSN2
3932 PC -> 0x08000003 : INSN4
3934 Say you're stopped at 0x08000003 as above. Reverse continuing
3935 from that point should hit B2 as below. Reading the PC when the
3936 SIGTRAP is reported should read 0x08000001 and INSN2 should have
3937 been de-executed already.
3939 B1 0x08000000 : INSN1
3940 B2 PC -> 0x08000001 : INSN2
3944 We can't apply the same logic as for forward execution, because
3945 we would wrongly adjust the PC to 0x08000000, since there's a
3946 breakpoint at PC - 1. We'd then report a hit on B1, although
3947 INSN1 hadn't been de-executed yet. Doing nothing is the correct
3949 if (execution_direction
== EXEC_REVERSE
)
3952 /* If the target can tell whether the thread hit a SW breakpoint,
3953 trust it. Targets that can tell also adjust the PC
3955 if (target_supports_stopped_by_sw_breakpoint ())
3958 /* Note that relying on whether a breakpoint is planted in memory to
3959 determine this can fail. E.g,. the breakpoint could have been
3960 removed since. Or the thread could have been told to step an
3961 instruction the size of a breakpoint instruction, and only
3962 _after_ was a breakpoint inserted at its address. */
3964 /* If this target does not decrement the PC after breakpoints, then
3965 we have nothing to do. */
3966 regcache
= get_thread_regcache (thread
);
3967 gdbarch
= regcache
->arch ();
3969 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3973 const address_space
*aspace
= regcache
->aspace ();
3975 /* Find the location where (if we've hit a breakpoint) the
3976 breakpoint would be. */
3977 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
3979 /* If the target can't tell whether a software breakpoint triggered,
3980 fallback to figuring it out based on breakpoints we think were
3981 inserted in the target, and on whether the thread was stepped or
3984 /* Check whether there actually is a software breakpoint inserted at
3987 If in non-stop mode, a race condition is possible where we've
3988 removed a breakpoint, but stop events for that breakpoint were
3989 already queued and arrive later. To suppress those spurious
3990 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
3991 and retire them after a number of stop events are reported. Note
3992 this is an heuristic and can thus get confused. The real fix is
3993 to get the "stopped by SW BP and needs adjustment" info out of
3994 the target/kernel (and thus never reach here; see above). */
3995 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
3996 || (target_is_non_stop_p ()
3997 && moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
3999 gdb::optional
<scoped_restore_tmpl
<int>> restore_operation_disable
;
4001 if (record_full_is_used ())
4002 restore_operation_disable
.emplace
4003 (record_full_gdb_operation_disable_set ());
4005 /* When using hardware single-step, a SIGTRAP is reported for both
4006 a completed single-step and a software breakpoint. Need to
4007 differentiate between the two, as the latter needs adjusting
4008 but the former does not.
4010 The SIGTRAP can be due to a completed hardware single-step only if
4011 - we didn't insert software single-step breakpoints
4012 - this thread is currently being stepped
4014 If any of these events did not occur, we must have stopped due
4015 to hitting a software breakpoint, and have to back up to the
4018 As a special case, we could have hardware single-stepped a
4019 software breakpoint. In this case (prev_pc == breakpoint_pc),
4020 we also need to back up to the breakpoint address. */
4022 if (thread_has_single_step_breakpoints_set (thread
)
4023 || !currently_stepping (thread
)
4024 || (thread
->stepped_breakpoint
4025 && thread
->prev_pc
== breakpoint_pc
))
4026 regcache_write_pc (regcache
, breakpoint_pc
);
4031 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
4033 for (frame
= get_prev_frame (frame
);
4035 frame
= get_prev_frame (frame
))
4037 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
4039 if (get_frame_type (frame
) != INLINE_FRAME
)
4046 /* If the event thread has the stop requested flag set, pretend it
4047 stopped for a GDB_SIGNAL_0 (i.e., as if it stopped due to
4051 handle_stop_requested (struct execution_control_state
*ecs
)
4053 if (ecs
->event_thread
->stop_requested
)
4055 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
4056 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
4057 handle_signal_stop (ecs
);
4063 /* Auxiliary function that handles syscall entry/return events.
4064 It returns 1 if the inferior should keep going (and GDB
4065 should ignore the event), or 0 if the event deserves to be
4069 handle_syscall_event (struct execution_control_state
*ecs
)
4071 struct regcache
*regcache
;
4074 context_switch (ecs
);
4076 regcache
= get_thread_regcache (ecs
->event_thread
);
4077 syscall_number
= ecs
->ws
.value
.syscall_number
;
4078 ecs
->event_thread
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4080 if (catch_syscall_enabled () > 0
4081 && catching_syscall_number (syscall_number
) > 0)
4084 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
4087 ecs
->event_thread
->control
.stop_bpstat
4088 = bpstat_stop_status (regcache
->aspace (),
4089 ecs
->event_thread
->suspend
.stop_pc
,
4090 ecs
->event_thread
, &ecs
->ws
);
4092 if (handle_stop_requested (ecs
))
4095 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4097 /* Catchpoint hit. */
4102 if (handle_stop_requested (ecs
))
4105 /* If no catchpoint triggered for this, then keep going. */
4110 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4113 fill_in_stop_func (struct gdbarch
*gdbarch
,
4114 struct execution_control_state
*ecs
)
4116 if (!ecs
->stop_func_filled_in
)
4120 /* Don't care about return value; stop_func_start and stop_func_name
4121 will both be 0 if it doesn't work. */
4122 find_pc_partial_function (ecs
->event_thread
->suspend
.stop_pc
,
4123 &ecs
->stop_func_name
,
4124 &ecs
->stop_func_start
,
4125 &ecs
->stop_func_end
,
4128 /* The call to find_pc_partial_function, above, will set
4129 stop_func_start and stop_func_end to the start and end
4130 of the range containing the stop pc. If this range
4131 contains the entry pc for the block (which is always the
4132 case for contiguous blocks), advance stop_func_start past
4133 the function's start offset and entrypoint. Note that
4134 stop_func_start is NOT advanced when in a range of a
4135 non-contiguous block that does not contain the entry pc. */
4136 if (block
!= nullptr
4137 && ecs
->stop_func_start
<= BLOCK_ENTRY_PC (block
)
4138 && BLOCK_ENTRY_PC (block
) < ecs
->stop_func_end
)
4140 ecs
->stop_func_start
4141 += gdbarch_deprecated_function_start_offset (gdbarch
);
4143 if (gdbarch_skip_entrypoint_p (gdbarch
))
4144 ecs
->stop_func_start
4145 = gdbarch_skip_entrypoint (gdbarch
, ecs
->stop_func_start
);
4148 ecs
->stop_func_filled_in
= 1;
4153 /* Return the STOP_SOON field of the inferior pointed at by ECS. */
4155 static enum stop_kind
4156 get_inferior_stop_soon (execution_control_state
*ecs
)
4158 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
4160 gdb_assert (inf
!= NULL
);
4161 return inf
->control
.stop_soon
;
4164 /* Wait for one event. Store the resulting waitstatus in WS, and
4165 return the event ptid. */
4168 wait_one (struct target_waitstatus
*ws
)
4171 ptid_t wait_ptid
= minus_one_ptid
;
4173 overlay_cache_invalid
= 1;
4175 /* Flush target cache before starting to handle each event.
4176 Target was running and cache could be stale. This is just a
4177 heuristic. Running threads may modify target memory, but we
4178 don't get any event. */
4179 target_dcache_invalidate ();
4181 if (deprecated_target_wait_hook
)
4182 event_ptid
= deprecated_target_wait_hook (wait_ptid
, ws
, 0);
4184 event_ptid
= target_wait (wait_ptid
, ws
, 0);
4187 print_target_wait_results (wait_ptid
, event_ptid
, ws
);
4192 /* Generate a wrapper for target_stopped_by_REASON that works on PTID
4193 instead of the current thread. */
4194 #define THREAD_STOPPED_BY(REASON) \
4196 thread_stopped_by_ ## REASON (ptid_t ptid) \
4198 scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid); \
4199 inferior_ptid = ptid; \
4201 return target_stopped_by_ ## REASON (); \
4204 /* Generate thread_stopped_by_watchpoint. */
4205 THREAD_STOPPED_BY (watchpoint
)
4206 /* Generate thread_stopped_by_sw_breakpoint. */
4207 THREAD_STOPPED_BY (sw_breakpoint
)
4208 /* Generate thread_stopped_by_hw_breakpoint. */
4209 THREAD_STOPPED_BY (hw_breakpoint
)
4211 /* Save the thread's event and stop reason to process it later. */
4214 save_waitstatus (struct thread_info
*tp
, struct target_waitstatus
*ws
)
4218 std::string statstr
= target_waitstatus_to_string (ws
);
4220 fprintf_unfiltered (gdb_stdlog
,
4221 "infrun: saving status %s for %d.%ld.%ld\n",
4228 /* Record for later. */
4229 tp
->suspend
.waitstatus
= *ws
;
4230 tp
->suspend
.waitstatus_pending_p
= 1;
4232 struct regcache
*regcache
= get_thread_regcache (tp
);
4233 const address_space
*aspace
= regcache
->aspace ();
4235 if (ws
->kind
== TARGET_WAITKIND_STOPPED
4236 && ws
->value
.sig
== GDB_SIGNAL_TRAP
)
4238 CORE_ADDR pc
= regcache_read_pc (regcache
);
4240 adjust_pc_after_break (tp
, &tp
->suspend
.waitstatus
);
4242 if (thread_stopped_by_watchpoint (tp
->ptid
))
4244 tp
->suspend
.stop_reason
4245 = TARGET_STOPPED_BY_WATCHPOINT
;
4247 else if (target_supports_stopped_by_sw_breakpoint ()
4248 && thread_stopped_by_sw_breakpoint (tp
->ptid
))
4250 tp
->suspend
.stop_reason
4251 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4253 else if (target_supports_stopped_by_hw_breakpoint ()
4254 && thread_stopped_by_hw_breakpoint (tp
->ptid
))
4256 tp
->suspend
.stop_reason
4257 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4259 else if (!target_supports_stopped_by_hw_breakpoint ()
4260 && hardware_breakpoint_inserted_here_p (aspace
,
4263 tp
->suspend
.stop_reason
4264 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4266 else if (!target_supports_stopped_by_sw_breakpoint ()
4267 && software_breakpoint_inserted_here_p (aspace
,
4270 tp
->suspend
.stop_reason
4271 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4273 else if (!thread_has_single_step_breakpoints_set (tp
)
4274 && currently_stepping (tp
))
4276 tp
->suspend
.stop_reason
4277 = TARGET_STOPPED_BY_SINGLE_STEP
;
4285 stop_all_threads (void)
4287 /* We may need multiple passes to discover all threads. */
4291 gdb_assert (target_is_non_stop_p ());
4294 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads\n");
4296 scoped_restore_current_thread restore_thread
;
4298 target_thread_events (1);
4299 SCOPE_EXIT
{ target_thread_events (0); };
4301 /* Request threads to stop, and then wait for the stops. Because
4302 threads we already know about can spawn more threads while we're
4303 trying to stop them, and we only learn about new threads when we
4304 update the thread list, do this in a loop, and keep iterating
4305 until two passes find no threads that need to be stopped. */
4306 for (pass
= 0; pass
< 2; pass
++, iterations
++)
4309 fprintf_unfiltered (gdb_stdlog
,
4310 "infrun: stop_all_threads, pass=%d, "
4311 "iterations=%d\n", pass
, iterations
);
4315 struct target_waitstatus ws
;
4318 update_thread_list ();
4320 /* Go through all threads looking for threads that we need
4321 to tell the target to stop. */
4322 for (thread_info
*t
: all_non_exited_threads ())
4326 /* If already stopping, don't request a stop again.
4327 We just haven't seen the notification yet. */
4328 if (!t
->stop_requested
)
4331 fprintf_unfiltered (gdb_stdlog
,
4332 "infrun: %s executing, "
4334 target_pid_to_str (t
->ptid
).c_str ());
4335 target_stop (t
->ptid
);
4336 t
->stop_requested
= 1;
4341 fprintf_unfiltered (gdb_stdlog
,
4342 "infrun: %s executing, "
4343 "already stopping\n",
4344 target_pid_to_str (t
->ptid
).c_str ());
4347 if (t
->stop_requested
)
4353 fprintf_unfiltered (gdb_stdlog
,
4354 "infrun: %s not executing\n",
4355 target_pid_to_str (t
->ptid
).c_str ());
4357 /* The thread may be not executing, but still be
4358 resumed with a pending status to process. */
4366 /* If we find new threads on the second iteration, restart
4367 over. We want to see two iterations in a row with all
4372 event_ptid
= wait_one (&ws
);
4375 fprintf_unfiltered (gdb_stdlog
,
4376 "infrun: stop_all_threads %s %s\n",
4377 target_waitstatus_to_string (&ws
).c_str (),
4378 target_pid_to_str (event_ptid
).c_str ());
4381 if (ws
.kind
== TARGET_WAITKIND_NO_RESUMED
4382 || ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
4383 || ws
.kind
== TARGET_WAITKIND_EXITED
4384 || ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
4386 /* All resumed threads exited
4387 or one thread/process exited/signalled. */
4391 thread_info
*t
= find_thread_ptid (event_ptid
);
4393 t
= add_thread (event_ptid
);
4395 t
->stop_requested
= 0;
4398 t
->control
.may_range_step
= 0;
4400 /* This may be the first time we see the inferior report
4402 inferior
*inf
= find_inferior_ptid (event_ptid
);
4403 if (inf
->needs_setup
)
4405 switch_to_thread_no_regs (t
);
4409 if (ws
.kind
== TARGET_WAITKIND_STOPPED
4410 && ws
.value
.sig
== GDB_SIGNAL_0
)
4412 /* We caught the event that we intended to catch, so
4413 there's no event pending. */
4414 t
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
4415 t
->suspend
.waitstatus_pending_p
= 0;
4417 if (displaced_step_fixup (t
, GDB_SIGNAL_0
) < 0)
4419 /* Add it back to the step-over queue. */
4422 fprintf_unfiltered (gdb_stdlog
,
4423 "infrun: displaced-step of %s "
4424 "canceled: adding back to the "
4425 "step-over queue\n",
4426 target_pid_to_str (t
->ptid
).c_str ());
4428 t
->control
.trap_expected
= 0;
4429 thread_step_over_chain_enqueue (t
);
4434 enum gdb_signal sig
;
4435 struct regcache
*regcache
;
4439 std::string statstr
= target_waitstatus_to_string (&ws
);
4441 fprintf_unfiltered (gdb_stdlog
,
4442 "infrun: target_wait %s, saving "
4443 "status for %d.%ld.%ld\n",
4450 /* Record for later. */
4451 save_waitstatus (t
, &ws
);
4453 sig
= (ws
.kind
== TARGET_WAITKIND_STOPPED
4454 ? ws
.value
.sig
: GDB_SIGNAL_0
);
4456 if (displaced_step_fixup (t
, sig
) < 0)
4458 /* Add it back to the step-over queue. */
4459 t
->control
.trap_expected
= 0;
4460 thread_step_over_chain_enqueue (t
);
4463 regcache
= get_thread_regcache (t
);
4464 t
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4468 fprintf_unfiltered (gdb_stdlog
,
4469 "infrun: saved stop_pc=%s for %s "
4470 "(currently_stepping=%d)\n",
4471 paddress (target_gdbarch (),
4472 t
->suspend
.stop_pc
),
4473 target_pid_to_str (t
->ptid
).c_str (),
4474 currently_stepping (t
));
4482 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads done\n");
4485 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
4488 handle_no_resumed (struct execution_control_state
*ecs
)
4490 if (target_can_async_p ())
4497 if (ui
->prompt_state
== PROMPT_BLOCKED
)
4505 /* There were no unwaited-for children left in the target, but,
4506 we're not synchronously waiting for events either. Just
4510 fprintf_unfiltered (gdb_stdlog
,
4511 "infrun: TARGET_WAITKIND_NO_RESUMED "
4512 "(ignoring: bg)\n");
4513 prepare_to_wait (ecs
);
4518 /* Otherwise, if we were running a synchronous execution command, we
4519 may need to cancel it and give the user back the terminal.
4521 In non-stop mode, the target can't tell whether we've already
4522 consumed previous stop events, so it can end up sending us a
4523 no-resumed event like so:
4525 #0 - thread 1 is left stopped
4527 #1 - thread 2 is resumed and hits breakpoint
4528 -> TARGET_WAITKIND_STOPPED
4530 #2 - thread 3 is resumed and exits
4531 this is the last resumed thread, so
4532 -> TARGET_WAITKIND_NO_RESUMED
4534 #3 - gdb processes stop for thread 2 and decides to re-resume
4537 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
4538 thread 2 is now resumed, so the event should be ignored.
4540 IOW, if the stop for thread 2 doesn't end a foreground command,
4541 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
4542 event. But it could be that the event meant that thread 2 itself
4543 (or whatever other thread was the last resumed thread) exited.
4545 To address this we refresh the thread list and check whether we
4546 have resumed threads _now_. In the example above, this removes
4547 thread 3 from the thread list. If thread 2 was re-resumed, we
4548 ignore this event. If we find no thread resumed, then we cancel
4549 the synchronous command show "no unwaited-for " to the user. */
4550 update_thread_list ();
4552 for (thread_info
*thread
: all_non_exited_threads ())
4554 if (thread
->executing
4555 || thread
->suspend
.waitstatus_pending_p
)
4557 /* There were no unwaited-for children left in the target at
4558 some point, but there are now. Just ignore. */
4560 fprintf_unfiltered (gdb_stdlog
,
4561 "infrun: TARGET_WAITKIND_NO_RESUMED "
4562 "(ignoring: found resumed)\n");
4563 prepare_to_wait (ecs
);
4568 /* Note however that we may find no resumed thread because the whole
4569 process exited meanwhile (thus updating the thread list results
4570 in an empty thread list). In this case we know we'll be getting
4571 a process exit event shortly. */
4572 for (inferior
*inf
: all_inferiors ())
4577 thread_info
*thread
= any_live_thread_of_inferior (inf
);
4581 fprintf_unfiltered (gdb_stdlog
,
4582 "infrun: TARGET_WAITKIND_NO_RESUMED "
4583 "(expect process exit)\n");
4584 prepare_to_wait (ecs
);
4589 /* Go ahead and report the event. */
4593 /* Given an execution control state that has been freshly filled in by
4594 an event from the inferior, figure out what it means and take
4597 The alternatives are:
4599 1) stop_waiting and return; to really stop and return to the
4602 2) keep_going and return; to wait for the next event (set
4603 ecs->event_thread->stepping_over_breakpoint to 1 to single step
4607 handle_inferior_event (struct execution_control_state
*ecs
)
4609 /* Make sure that all temporary struct value objects that were
4610 created during the handling of the event get deleted at the
4612 scoped_value_mark free_values
;
4614 enum stop_kind stop_soon
;
4617 fprintf_unfiltered (gdb_stdlog
, "infrun: handle_inferior_event %s\n",
4618 target_waitstatus_to_string (&ecs
->ws
).c_str ());
4620 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
4622 /* We had an event in the inferior, but we are not interested in
4623 handling it at this level. The lower layers have already
4624 done what needs to be done, if anything.
4626 One of the possible circumstances for this is when the
4627 inferior produces output for the console. The inferior has
4628 not stopped, and we are ignoring the event. Another possible
4629 circumstance is any event which the lower level knows will be
4630 reported multiple times without an intervening resume. */
4631 prepare_to_wait (ecs
);
4635 if (ecs
->ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
)
4637 prepare_to_wait (ecs
);
4641 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
4642 && handle_no_resumed (ecs
))
4645 /* Cache the last pid/waitstatus. */
4646 set_last_target_status (ecs
->ptid
, ecs
->ws
);
4648 /* Always clear state belonging to the previous time we stopped. */
4649 stop_stack_dummy
= STOP_NONE
;
4651 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4653 /* No unwaited-for children left. IOW, all resumed children
4655 stop_print_frame
= 0;
4660 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
4661 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
4663 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
4664 /* If it's a new thread, add it to the thread database. */
4665 if (ecs
->event_thread
== NULL
)
4666 ecs
->event_thread
= add_thread (ecs
->ptid
);
4668 /* Disable range stepping. If the next step request could use a
4669 range, this will be end up re-enabled then. */
4670 ecs
->event_thread
->control
.may_range_step
= 0;
4673 /* Dependent on valid ECS->EVENT_THREAD. */
4674 adjust_pc_after_break (ecs
->event_thread
, &ecs
->ws
);
4676 /* Dependent on the current PC value modified by adjust_pc_after_break. */
4677 reinit_frame_cache ();
4679 breakpoint_retire_moribund ();
4681 /* First, distinguish signals caused by the debugger from signals
4682 that have to do with the program's own actions. Note that
4683 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
4684 on the operating system version. Here we detect when a SIGILL or
4685 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
4686 something similar for SIGSEGV, since a SIGSEGV will be generated
4687 when we're trying to execute a breakpoint instruction on a
4688 non-executable stack. This happens for call dummy breakpoints
4689 for architectures like SPARC that place call dummies on the
4691 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
4692 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
4693 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
4694 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
4696 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
4698 if (breakpoint_inserted_here_p (regcache
->aspace (),
4699 regcache_read_pc (regcache
)))
4702 fprintf_unfiltered (gdb_stdlog
,
4703 "infrun: Treating signal as SIGTRAP\n");
4704 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
4708 /* Mark the non-executing threads accordingly. In all-stop, all
4709 threads of all processes are stopped when we get any event
4710 reported. In non-stop mode, only the event thread stops. */
4714 if (!target_is_non_stop_p ())
4715 mark_ptid
= minus_one_ptid
;
4716 else if (ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
4717 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4719 /* If we're handling a process exit in non-stop mode, even
4720 though threads haven't been deleted yet, one would think
4721 that there is nothing to do, as threads of the dead process
4722 will be soon deleted, and threads of any other process were
4723 left running. However, on some targets, threads survive a
4724 process exit event. E.g., for the "checkpoint" command,
4725 when the current checkpoint/fork exits, linux-fork.c
4726 automatically switches to another fork from within
4727 target_mourn_inferior, by associating the same
4728 inferior/thread to another fork. We haven't mourned yet at
4729 this point, but we must mark any threads left in the
4730 process as not-executing so that finish_thread_state marks
4731 them stopped (in the user's perspective) if/when we present
4732 the stop to the user. */
4733 mark_ptid
= ptid_t (ecs
->ptid
.pid ());
4736 mark_ptid
= ecs
->ptid
;
4738 set_executing (mark_ptid
, 0);
4740 /* Likewise the resumed flag. */
4741 set_resumed (mark_ptid
, 0);
4744 switch (ecs
->ws
.kind
)
4746 case TARGET_WAITKIND_LOADED
:
4747 context_switch (ecs
);
4748 /* Ignore gracefully during startup of the inferior, as it might
4749 be the shell which has just loaded some objects, otherwise
4750 add the symbols for the newly loaded objects. Also ignore at
4751 the beginning of an attach or remote session; we will query
4752 the full list of libraries once the connection is
4755 stop_soon
= get_inferior_stop_soon (ecs
);
4756 if (stop_soon
== NO_STOP_QUIETLY
)
4758 struct regcache
*regcache
;
4760 regcache
= get_thread_regcache (ecs
->event_thread
);
4762 handle_solib_event ();
4764 ecs
->event_thread
->control
.stop_bpstat
4765 = bpstat_stop_status (regcache
->aspace (),
4766 ecs
->event_thread
->suspend
.stop_pc
,
4767 ecs
->event_thread
, &ecs
->ws
);
4769 if (handle_stop_requested (ecs
))
4772 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4774 /* A catchpoint triggered. */
4775 process_event_stop_test (ecs
);
4779 /* If requested, stop when the dynamic linker notifies
4780 gdb of events. This allows the user to get control
4781 and place breakpoints in initializer routines for
4782 dynamically loaded objects (among other things). */
4783 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4784 if (stop_on_solib_events
)
4786 /* Make sure we print "Stopped due to solib-event" in
4788 stop_print_frame
= 1;
4795 /* If we are skipping through a shell, or through shared library
4796 loading that we aren't interested in, resume the program. If
4797 we're running the program normally, also resume. */
4798 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
4800 /* Loading of shared libraries might have changed breakpoint
4801 addresses. Make sure new breakpoints are inserted. */
4802 if (stop_soon
== NO_STOP_QUIETLY
)
4803 insert_breakpoints ();
4804 resume (GDB_SIGNAL_0
);
4805 prepare_to_wait (ecs
);
4809 /* But stop if we're attaching or setting up a remote
4811 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4812 || stop_soon
== STOP_QUIETLY_REMOTE
)
4815 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
4820 internal_error (__FILE__
, __LINE__
,
4821 _("unhandled stop_soon: %d"), (int) stop_soon
);
4823 case TARGET_WAITKIND_SPURIOUS
:
4824 if (handle_stop_requested (ecs
))
4826 context_switch (ecs
);
4827 resume (GDB_SIGNAL_0
);
4828 prepare_to_wait (ecs
);
4831 case TARGET_WAITKIND_THREAD_CREATED
:
4832 if (handle_stop_requested (ecs
))
4834 context_switch (ecs
);
4835 if (!switch_back_to_stepped_thread (ecs
))
4839 case TARGET_WAITKIND_EXITED
:
4840 case TARGET_WAITKIND_SIGNALLED
:
4841 inferior_ptid
= ecs
->ptid
;
4842 set_current_inferior (find_inferior_ptid (ecs
->ptid
));
4843 set_current_program_space (current_inferior ()->pspace
);
4844 handle_vfork_child_exec_or_exit (0);
4845 target_terminal::ours (); /* Must do this before mourn anyway. */
4847 /* Clearing any previous state of convenience variables. */
4848 clear_exit_convenience_vars ();
4850 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4852 /* Record the exit code in the convenience variable $_exitcode, so
4853 that the user can inspect this again later. */
4854 set_internalvar_integer (lookup_internalvar ("_exitcode"),
4855 (LONGEST
) ecs
->ws
.value
.integer
);
4857 /* Also record this in the inferior itself. */
4858 current_inferior ()->has_exit_code
= 1;
4859 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
4861 /* Support the --return-child-result option. */
4862 return_child_result_value
= ecs
->ws
.value
.integer
;
4864 gdb::observers::exited
.notify (ecs
->ws
.value
.integer
);
4868 struct gdbarch
*gdbarch
= current_inferior ()->gdbarch
;
4870 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
4872 /* Set the value of the internal variable $_exitsignal,
4873 which holds the signal uncaught by the inferior. */
4874 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
4875 gdbarch_gdb_signal_to_target (gdbarch
,
4876 ecs
->ws
.value
.sig
));
4880 /* We don't have access to the target's method used for
4881 converting between signal numbers (GDB's internal
4882 representation <-> target's representation).
4883 Therefore, we cannot do a good job at displaying this
4884 information to the user. It's better to just warn
4885 her about it (if infrun debugging is enabled), and
4888 fprintf_filtered (gdb_stdlog
, _("\
4889 Cannot fill $_exitsignal with the correct signal number.\n"));
4892 gdb::observers::signal_exited
.notify (ecs
->ws
.value
.sig
);
4895 gdb_flush (gdb_stdout
);
4896 target_mourn_inferior (inferior_ptid
);
4897 stop_print_frame
= 0;
4901 /* The following are the only cases in which we keep going;
4902 the above cases end in a continue or goto. */
4903 case TARGET_WAITKIND_FORKED
:
4904 case TARGET_WAITKIND_VFORKED
:
4905 /* Check whether the inferior is displaced stepping. */
4907 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
4908 struct gdbarch
*gdbarch
= regcache
->arch ();
4910 /* If checking displaced stepping is supported, and thread
4911 ecs->ptid is displaced stepping. */
4912 if (displaced_step_in_progress_thread (ecs
->event_thread
))
4914 struct inferior
*parent_inf
4915 = find_inferior_ptid (ecs
->ptid
);
4916 struct regcache
*child_regcache
;
4917 CORE_ADDR parent_pc
;
4919 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
4920 indicating that the displaced stepping of syscall instruction
4921 has been done. Perform cleanup for parent process here. Note
4922 that this operation also cleans up the child process for vfork,
4923 because their pages are shared. */
4924 displaced_step_fixup (ecs
->event_thread
, GDB_SIGNAL_TRAP
);
4925 /* Start a new step-over in another thread if there's one
4929 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
4931 struct displaced_step_inferior_state
*displaced
4932 = get_displaced_stepping_state (parent_inf
);
4934 /* Restore scratch pad for child process. */
4935 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
4938 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
4939 the child's PC is also within the scratchpad. Set the child's PC
4940 to the parent's PC value, which has already been fixed up.
4941 FIXME: we use the parent's aspace here, although we're touching
4942 the child, because the child hasn't been added to the inferior
4943 list yet at this point. */
4946 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
4948 parent_inf
->aspace
);
4949 /* Read PC value of parent process. */
4950 parent_pc
= regcache_read_pc (regcache
);
4952 if (debug_displaced
)
4953 fprintf_unfiltered (gdb_stdlog
,
4954 "displaced: write child pc from %s to %s\n",
4956 regcache_read_pc (child_regcache
)),
4957 paddress (gdbarch
, parent_pc
));
4959 regcache_write_pc (child_regcache
, parent_pc
);
4963 context_switch (ecs
);
4965 /* Immediately detach breakpoints from the child before there's
4966 any chance of letting the user delete breakpoints from the
4967 breakpoint lists. If we don't do this early, it's easy to
4968 leave left over traps in the child, vis: "break foo; catch
4969 fork; c; <fork>; del; c; <child calls foo>". We only follow
4970 the fork on the last `continue', and by that time the
4971 breakpoint at "foo" is long gone from the breakpoint table.
4972 If we vforked, then we don't need to unpatch here, since both
4973 parent and child are sharing the same memory pages; we'll
4974 need to unpatch at follow/detach time instead to be certain
4975 that new breakpoints added between catchpoint hit time and
4976 vfork follow are detached. */
4977 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
4979 /* This won't actually modify the breakpoint list, but will
4980 physically remove the breakpoints from the child. */
4981 detach_breakpoints (ecs
->ws
.value
.related_pid
);
4984 delete_just_stopped_threads_single_step_breakpoints ();
4986 /* In case the event is caught by a catchpoint, remember that
4987 the event is to be followed at the next resume of the thread,
4988 and not immediately. */
4989 ecs
->event_thread
->pending_follow
= ecs
->ws
;
4991 ecs
->event_thread
->suspend
.stop_pc
4992 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
4994 ecs
->event_thread
->control
.stop_bpstat
4995 = bpstat_stop_status (get_current_regcache ()->aspace (),
4996 ecs
->event_thread
->suspend
.stop_pc
,
4997 ecs
->event_thread
, &ecs
->ws
);
4999 if (handle_stop_requested (ecs
))
5002 /* If no catchpoint triggered for this, then keep going. Note
5003 that we're interested in knowing the bpstat actually causes a
5004 stop, not just if it may explain the signal. Software
5005 watchpoints, for example, always appear in the bpstat. */
5006 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5010 = (follow_fork_mode_string
== follow_fork_mode_child
);
5012 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5014 should_resume
= follow_fork ();
5016 thread_info
*parent
= ecs
->event_thread
;
5017 thread_info
*child
= find_thread_ptid (ecs
->ws
.value
.related_pid
);
5019 /* At this point, the parent is marked running, and the
5020 child is marked stopped. */
5022 /* If not resuming the parent, mark it stopped. */
5023 if (follow_child
&& !detach_fork
&& !non_stop
&& !sched_multi
)
5024 parent
->set_running (false);
5026 /* If resuming the child, mark it running. */
5027 if (follow_child
|| (!detach_fork
&& (non_stop
|| sched_multi
)))
5028 child
->set_running (true);
5030 /* In non-stop mode, also resume the other branch. */
5031 if (!detach_fork
&& (non_stop
5032 || (sched_multi
&& target_is_non_stop_p ())))
5035 switch_to_thread (parent
);
5037 switch_to_thread (child
);
5039 ecs
->event_thread
= inferior_thread ();
5040 ecs
->ptid
= inferior_ptid
;
5045 switch_to_thread (child
);
5047 switch_to_thread (parent
);
5049 ecs
->event_thread
= inferior_thread ();
5050 ecs
->ptid
= inferior_ptid
;
5058 process_event_stop_test (ecs
);
5061 case TARGET_WAITKIND_VFORK_DONE
:
5062 /* Done with the shared memory region. Re-insert breakpoints in
5063 the parent, and keep going. */
5065 context_switch (ecs
);
5067 current_inferior ()->waiting_for_vfork_done
= 0;
5068 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
5070 if (handle_stop_requested (ecs
))
5073 /* This also takes care of reinserting breakpoints in the
5074 previously locked inferior. */
5078 case TARGET_WAITKIND_EXECD
:
5080 /* Note we can't read registers yet (the stop_pc), because we
5081 don't yet know the inferior's post-exec architecture.
5082 'stop_pc' is explicitly read below instead. */
5083 switch_to_thread_no_regs (ecs
->event_thread
);
5085 /* Do whatever is necessary to the parent branch of the vfork. */
5086 handle_vfork_child_exec_or_exit (1);
5088 /* This causes the eventpoints and symbol table to be reset.
5089 Must do this now, before trying to determine whether to
5091 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
5093 /* In follow_exec we may have deleted the original thread and
5094 created a new one. Make sure that the event thread is the
5095 execd thread for that case (this is a nop otherwise). */
5096 ecs
->event_thread
= inferior_thread ();
5098 ecs
->event_thread
->suspend
.stop_pc
5099 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
5101 ecs
->event_thread
->control
.stop_bpstat
5102 = bpstat_stop_status (get_current_regcache ()->aspace (),
5103 ecs
->event_thread
->suspend
.stop_pc
,
5104 ecs
->event_thread
, &ecs
->ws
);
5106 /* Note that this may be referenced from inside
5107 bpstat_stop_status above, through inferior_has_execd. */
5108 xfree (ecs
->ws
.value
.execd_pathname
);
5109 ecs
->ws
.value
.execd_pathname
= NULL
;
5111 if (handle_stop_requested (ecs
))
5114 /* If no catchpoint triggered for this, then keep going. */
5115 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5117 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5121 process_event_stop_test (ecs
);
5124 /* Be careful not to try to gather much state about a thread
5125 that's in a syscall. It's frequently a losing proposition. */
5126 case TARGET_WAITKIND_SYSCALL_ENTRY
:
5127 /* Getting the current syscall number. */
5128 if (handle_syscall_event (ecs
) == 0)
5129 process_event_stop_test (ecs
);
5132 /* Before examining the threads further, step this thread to
5133 get it entirely out of the syscall. (We get notice of the
5134 event when the thread is just on the verge of exiting a
5135 syscall. Stepping one instruction seems to get it back
5137 case TARGET_WAITKIND_SYSCALL_RETURN
:
5138 if (handle_syscall_event (ecs
) == 0)
5139 process_event_stop_test (ecs
);
5142 case TARGET_WAITKIND_STOPPED
:
5143 handle_signal_stop (ecs
);
5146 case TARGET_WAITKIND_NO_HISTORY
:
5147 /* Reverse execution: target ran out of history info. */
5149 /* Switch to the stopped thread. */
5150 context_switch (ecs
);
5152 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
5154 delete_just_stopped_threads_single_step_breakpoints ();
5155 ecs
->event_thread
->suspend
.stop_pc
5156 = regcache_read_pc (get_thread_regcache (inferior_thread ()));
5158 if (handle_stop_requested (ecs
))
5161 gdb::observers::no_history
.notify ();
5167 /* Restart threads back to what they were trying to do back when we
5168 paused them for an in-line step-over. The EVENT_THREAD thread is
5172 restart_threads (struct thread_info
*event_thread
)
5174 /* In case the instruction just stepped spawned a new thread. */
5175 update_thread_list ();
5177 for (thread_info
*tp
: all_non_exited_threads ())
5179 if (tp
== event_thread
)
5182 fprintf_unfiltered (gdb_stdlog
,
5183 "infrun: restart threads: "
5184 "[%s] is event thread\n",
5185 target_pid_to_str (tp
->ptid
).c_str ());
5189 if (!(tp
->state
== THREAD_RUNNING
|| tp
->control
.in_infcall
))
5192 fprintf_unfiltered (gdb_stdlog
,
5193 "infrun: restart threads: "
5194 "[%s] not meant to be running\n",
5195 target_pid_to_str (tp
->ptid
).c_str ());
5202 fprintf_unfiltered (gdb_stdlog
,
5203 "infrun: restart threads: [%s] resumed\n",
5204 target_pid_to_str (tp
->ptid
).c_str ());
5205 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
5209 if (thread_is_in_step_over_chain (tp
))
5212 fprintf_unfiltered (gdb_stdlog
,
5213 "infrun: restart threads: "
5214 "[%s] needs step-over\n",
5215 target_pid_to_str (tp
->ptid
).c_str ());
5216 gdb_assert (!tp
->resumed
);
5221 if (tp
->suspend
.waitstatus_pending_p
)
5224 fprintf_unfiltered (gdb_stdlog
,
5225 "infrun: restart threads: "
5226 "[%s] has pending status\n",
5227 target_pid_to_str (tp
->ptid
).c_str ());
5232 gdb_assert (!tp
->stop_requested
);
5234 /* If some thread needs to start a step-over at this point, it
5235 should still be in the step-over queue, and thus skipped
5237 if (thread_still_needs_step_over (tp
))
5239 internal_error (__FILE__
, __LINE__
,
5240 "thread [%s] needs a step-over, but not in "
5241 "step-over queue\n",
5242 target_pid_to_str (tp
->ptid
).c_str ());
5245 if (currently_stepping (tp
))
5248 fprintf_unfiltered (gdb_stdlog
,
5249 "infrun: restart threads: [%s] was stepping\n",
5250 target_pid_to_str (tp
->ptid
).c_str ());
5251 keep_going_stepped_thread (tp
);
5255 struct execution_control_state ecss
;
5256 struct execution_control_state
*ecs
= &ecss
;
5259 fprintf_unfiltered (gdb_stdlog
,
5260 "infrun: restart threads: [%s] continuing\n",
5261 target_pid_to_str (tp
->ptid
).c_str ());
5262 reset_ecs (ecs
, tp
);
5263 switch_to_thread (tp
);
5264 keep_going_pass_signal (ecs
);
5269 /* Callback for iterate_over_threads. Find a resumed thread that has
5270 a pending waitstatus. */
5273 resumed_thread_with_pending_status (struct thread_info
*tp
,
5277 && tp
->suspend
.waitstatus_pending_p
);
5280 /* Called when we get an event that may finish an in-line or
5281 out-of-line (displaced stepping) step-over started previously.
5282 Return true if the event is processed and we should go back to the
5283 event loop; false if the caller should continue processing the
5287 finish_step_over (struct execution_control_state
*ecs
)
5289 int had_step_over_info
;
5291 displaced_step_fixup (ecs
->event_thread
,
5292 ecs
->event_thread
->suspend
.stop_signal
);
5294 had_step_over_info
= step_over_info_valid_p ();
5296 if (had_step_over_info
)
5298 /* If we're stepping over a breakpoint with all threads locked,
5299 then only the thread that was stepped should be reporting
5301 gdb_assert (ecs
->event_thread
->control
.trap_expected
);
5303 clear_step_over_info ();
5306 if (!target_is_non_stop_p ())
5309 /* Start a new step-over in another thread if there's one that
5313 /* If we were stepping over a breakpoint before, and haven't started
5314 a new in-line step-over sequence, then restart all other threads
5315 (except the event thread). We can't do this in all-stop, as then
5316 e.g., we wouldn't be able to issue any other remote packet until
5317 these other threads stop. */
5318 if (had_step_over_info
&& !step_over_info_valid_p ())
5320 struct thread_info
*pending
;
5322 /* If we only have threads with pending statuses, the restart
5323 below won't restart any thread and so nothing re-inserts the
5324 breakpoint we just stepped over. But we need it inserted
5325 when we later process the pending events, otherwise if
5326 another thread has a pending event for this breakpoint too,
5327 we'd discard its event (because the breakpoint that
5328 originally caused the event was no longer inserted). */
5329 context_switch (ecs
);
5330 insert_breakpoints ();
5332 restart_threads (ecs
->event_thread
);
5334 /* If we have events pending, go through handle_inferior_event
5335 again, picking up a pending event at random. This avoids
5336 thread starvation. */
5338 /* But not if we just stepped over a watchpoint in order to let
5339 the instruction execute so we can evaluate its expression.
5340 The set of watchpoints that triggered is recorded in the
5341 breakpoint objects themselves (see bp->watchpoint_triggered).
5342 If we processed another event first, that other event could
5343 clobber this info. */
5344 if (ecs
->event_thread
->stepping_over_watchpoint
)
5347 pending
= iterate_over_threads (resumed_thread_with_pending_status
,
5349 if (pending
!= NULL
)
5351 struct thread_info
*tp
= ecs
->event_thread
;
5352 struct regcache
*regcache
;
5356 fprintf_unfiltered (gdb_stdlog
,
5357 "infrun: found resumed threads with "
5358 "pending events, saving status\n");
5361 gdb_assert (pending
!= tp
);
5363 /* Record the event thread's event for later. */
5364 save_waitstatus (tp
, &ecs
->ws
);
5365 /* This was cleared early, by handle_inferior_event. Set it
5366 so this pending event is considered by
5370 gdb_assert (!tp
->executing
);
5372 regcache
= get_thread_regcache (tp
);
5373 tp
->suspend
.stop_pc
= regcache_read_pc (regcache
);
5377 fprintf_unfiltered (gdb_stdlog
,
5378 "infrun: saved stop_pc=%s for %s "
5379 "(currently_stepping=%d)\n",
5380 paddress (target_gdbarch (),
5381 tp
->suspend
.stop_pc
),
5382 target_pid_to_str (tp
->ptid
).c_str (),
5383 currently_stepping (tp
));
5386 /* This in-line step-over finished; clear this so we won't
5387 start a new one. This is what handle_signal_stop would
5388 do, if we returned false. */
5389 tp
->stepping_over_breakpoint
= 0;
5391 /* Wake up the event loop again. */
5392 mark_async_event_handler (infrun_async_inferior_event_token
);
5394 prepare_to_wait (ecs
);
5402 /* Come here when the program has stopped with a signal. */
5405 handle_signal_stop (struct execution_control_state
*ecs
)
5407 struct frame_info
*frame
;
5408 struct gdbarch
*gdbarch
;
5409 int stopped_by_watchpoint
;
5410 enum stop_kind stop_soon
;
5413 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
5415 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
5417 /* Do we need to clean up the state of a thread that has
5418 completed a displaced single-step? (Doing so usually affects
5419 the PC, so do it here, before we set stop_pc.) */
5420 if (finish_step_over (ecs
))
5423 /* If we either finished a single-step or hit a breakpoint, but
5424 the user wanted this thread to be stopped, pretend we got a
5425 SIG0 (generic unsignaled stop). */
5426 if (ecs
->event_thread
->stop_requested
5427 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5428 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5430 ecs
->event_thread
->suspend
.stop_pc
5431 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
5435 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
5436 struct gdbarch
*reg_gdbarch
= regcache
->arch ();
5437 scoped_restore save_inferior_ptid
= make_scoped_restore (&inferior_ptid
);
5439 inferior_ptid
= ecs
->ptid
;
5441 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
5442 paddress (reg_gdbarch
,
5443 ecs
->event_thread
->suspend
.stop_pc
));
5444 if (target_stopped_by_watchpoint ())
5448 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
5450 if (target_stopped_data_address (current_top_target (), &addr
))
5451 fprintf_unfiltered (gdb_stdlog
,
5452 "infrun: stopped data address = %s\n",
5453 paddress (reg_gdbarch
, addr
));
5455 fprintf_unfiltered (gdb_stdlog
,
5456 "infrun: (no data address available)\n");
5460 /* This is originated from start_remote(), start_inferior() and
5461 shared libraries hook functions. */
5462 stop_soon
= get_inferior_stop_soon (ecs
);
5463 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
5465 context_switch (ecs
);
5467 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5468 stop_print_frame
= 1;
5473 /* This originates from attach_command(). We need to overwrite
5474 the stop_signal here, because some kernels don't ignore a
5475 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5476 See more comments in inferior.h. On the other hand, if we
5477 get a non-SIGSTOP, report it to the user - assume the backend
5478 will handle the SIGSTOP if it should show up later.
5480 Also consider that the attach is complete when we see a
5481 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5482 target extended-remote report it instead of a SIGSTOP
5483 (e.g. gdbserver). We already rely on SIGTRAP being our
5484 signal, so this is no exception.
5486 Also consider that the attach is complete when we see a
5487 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5488 the target to stop all threads of the inferior, in case the
5489 low level attach operation doesn't stop them implicitly. If
5490 they weren't stopped implicitly, then the stub will report a
5491 GDB_SIGNAL_0, meaning: stopped for no particular reason
5492 other than GDB's request. */
5493 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5494 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
5495 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5496 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
5498 stop_print_frame
= 1;
5500 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5504 /* See if something interesting happened to the non-current thread. If
5505 so, then switch to that thread. */
5506 if (ecs
->ptid
!= inferior_ptid
)
5509 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
5511 context_switch (ecs
);
5513 if (deprecated_context_hook
)
5514 deprecated_context_hook (ecs
->event_thread
->global_num
);
5517 /* At this point, get hold of the now-current thread's frame. */
5518 frame
= get_current_frame ();
5519 gdbarch
= get_frame_arch (frame
);
5521 /* Pull the single step breakpoints out of the target. */
5522 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5524 struct regcache
*regcache
;
5527 regcache
= get_thread_regcache (ecs
->event_thread
);
5528 const address_space
*aspace
= regcache
->aspace ();
5530 pc
= regcache_read_pc (regcache
);
5532 /* However, before doing so, if this single-step breakpoint was
5533 actually for another thread, set this thread up for moving
5535 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
5538 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
5542 fprintf_unfiltered (gdb_stdlog
,
5543 "infrun: [%s] hit another thread's "
5544 "single-step breakpoint\n",
5545 target_pid_to_str (ecs
->ptid
).c_str ());
5547 ecs
->hit_singlestep_breakpoint
= 1;
5554 fprintf_unfiltered (gdb_stdlog
,
5555 "infrun: [%s] hit its "
5556 "single-step breakpoint\n",
5557 target_pid_to_str (ecs
->ptid
).c_str ());
5561 delete_just_stopped_threads_single_step_breakpoints ();
5563 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5564 && ecs
->event_thread
->control
.trap_expected
5565 && ecs
->event_thread
->stepping_over_watchpoint
)
5566 stopped_by_watchpoint
= 0;
5568 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
5570 /* If necessary, step over this watchpoint. We'll be back to display
5572 if (stopped_by_watchpoint
5573 && (target_have_steppable_watchpoint
5574 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
5576 /* At this point, we are stopped at an instruction which has
5577 attempted to write to a piece of memory under control of
5578 a watchpoint. The instruction hasn't actually executed
5579 yet. If we were to evaluate the watchpoint expression
5580 now, we would get the old value, and therefore no change
5581 would seem to have occurred.
5583 In order to make watchpoints work `right', we really need
5584 to complete the memory write, and then evaluate the
5585 watchpoint expression. We do this by single-stepping the
5588 It may not be necessary to disable the watchpoint to step over
5589 it. For example, the PA can (with some kernel cooperation)
5590 single step over a watchpoint without disabling the watchpoint.
5592 It is far more common to need to disable a watchpoint to step
5593 the inferior over it. If we have non-steppable watchpoints,
5594 we must disable the current watchpoint; it's simplest to
5595 disable all watchpoints.
5597 Any breakpoint at PC must also be stepped over -- if there's
5598 one, it will have already triggered before the watchpoint
5599 triggered, and we either already reported it to the user, or
5600 it didn't cause a stop and we called keep_going. In either
5601 case, if there was a breakpoint at PC, we must be trying to
5603 ecs
->event_thread
->stepping_over_watchpoint
= 1;
5608 ecs
->event_thread
->stepping_over_breakpoint
= 0;
5609 ecs
->event_thread
->stepping_over_watchpoint
= 0;
5610 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
5611 ecs
->event_thread
->control
.stop_step
= 0;
5612 stop_print_frame
= 1;
5613 stopped_by_random_signal
= 0;
5614 bpstat stop_chain
= NULL
;
5616 /* Hide inlined functions starting here, unless we just performed stepi or
5617 nexti. After stepi and nexti, always show the innermost frame (not any
5618 inline function call sites). */
5619 if (ecs
->event_thread
->control
.step_range_end
!= 1)
5621 const address_space
*aspace
5622 = get_thread_regcache (ecs
->event_thread
)->aspace ();
5624 /* skip_inline_frames is expensive, so we avoid it if we can
5625 determine that the address is one where functions cannot have
5626 been inlined. This improves performance with inferiors that
5627 load a lot of shared libraries, because the solib event
5628 breakpoint is defined as the address of a function (i.e. not
5629 inline). Note that we have to check the previous PC as well
5630 as the current one to catch cases when we have just
5631 single-stepped off a breakpoint prior to reinstating it.
5632 Note that we're assuming that the code we single-step to is
5633 not inline, but that's not definitive: there's nothing
5634 preventing the event breakpoint function from containing
5635 inlined code, and the single-step ending up there. If the
5636 user had set a breakpoint on that inlined code, the missing
5637 skip_inline_frames call would break things. Fortunately
5638 that's an extremely unlikely scenario. */
5639 if (!pc_at_non_inline_function (aspace
,
5640 ecs
->event_thread
->suspend
.stop_pc
,
5642 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5643 && ecs
->event_thread
->control
.trap_expected
5644 && pc_at_non_inline_function (aspace
,
5645 ecs
->event_thread
->prev_pc
,
5648 stop_chain
= build_bpstat_chain (aspace
,
5649 ecs
->event_thread
->suspend
.stop_pc
,
5651 skip_inline_frames (ecs
->event_thread
, stop_chain
);
5653 /* Re-fetch current thread's frame in case that invalidated
5655 frame
= get_current_frame ();
5656 gdbarch
= get_frame_arch (frame
);
5660 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5661 && ecs
->event_thread
->control
.trap_expected
5662 && gdbarch_single_step_through_delay_p (gdbarch
)
5663 && currently_stepping (ecs
->event_thread
))
5665 /* We're trying to step off a breakpoint. Turns out that we're
5666 also on an instruction that needs to be stepped multiple
5667 times before it's been fully executing. E.g., architectures
5668 with a delay slot. It needs to be stepped twice, once for
5669 the instruction and once for the delay slot. */
5670 int step_through_delay
5671 = gdbarch_single_step_through_delay (gdbarch
, frame
);
5673 if (debug_infrun
&& step_through_delay
)
5674 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
5675 if (ecs
->event_thread
->control
.step_range_end
== 0
5676 && step_through_delay
)
5678 /* The user issued a continue when stopped at a breakpoint.
5679 Set up for another trap and get out of here. */
5680 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5684 else if (step_through_delay
)
5686 /* The user issued a step when stopped at a breakpoint.
5687 Maybe we should stop, maybe we should not - the delay
5688 slot *might* correspond to a line of source. In any
5689 case, don't decide that here, just set
5690 ecs->stepping_over_breakpoint, making sure we
5691 single-step again before breakpoints are re-inserted. */
5692 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5696 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
5697 handles this event. */
5698 ecs
->event_thread
->control
.stop_bpstat
5699 = bpstat_stop_status (get_current_regcache ()->aspace (),
5700 ecs
->event_thread
->suspend
.stop_pc
,
5701 ecs
->event_thread
, &ecs
->ws
, stop_chain
);
5703 /* Following in case break condition called a
5705 stop_print_frame
= 1;
5707 /* This is where we handle "moribund" watchpoints. Unlike
5708 software breakpoints traps, hardware watchpoint traps are
5709 always distinguishable from random traps. If no high-level
5710 watchpoint is associated with the reported stop data address
5711 anymore, then the bpstat does not explain the signal ---
5712 simply make sure to ignore it if `stopped_by_watchpoint' is
5716 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5717 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5719 && stopped_by_watchpoint
)
5720 fprintf_unfiltered (gdb_stdlog
,
5721 "infrun: no user watchpoint explains "
5722 "watchpoint SIGTRAP, ignoring\n");
5724 /* NOTE: cagney/2003-03-29: These checks for a random signal
5725 at one stage in the past included checks for an inferior
5726 function call's call dummy's return breakpoint. The original
5727 comment, that went with the test, read:
5729 ``End of a stack dummy. Some systems (e.g. Sony news) give
5730 another signal besides SIGTRAP, so check here as well as
5733 If someone ever tries to get call dummys on a
5734 non-executable stack to work (where the target would stop
5735 with something like a SIGSEGV), then those tests might need
5736 to be re-instated. Given, however, that the tests were only
5737 enabled when momentary breakpoints were not being used, I
5738 suspect that it won't be the case.
5740 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
5741 be necessary for call dummies on a non-executable stack on
5744 /* See if the breakpoints module can explain the signal. */
5746 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5747 ecs
->event_thread
->suspend
.stop_signal
);
5749 /* Maybe this was a trap for a software breakpoint that has since
5751 if (random_signal
&& target_stopped_by_sw_breakpoint ())
5753 if (program_breakpoint_here_p (gdbarch
,
5754 ecs
->event_thread
->suspend
.stop_pc
))
5756 struct regcache
*regcache
;
5759 /* Re-adjust PC to what the program would see if GDB was not
5761 regcache
= get_thread_regcache (ecs
->event_thread
);
5762 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
5765 gdb::optional
<scoped_restore_tmpl
<int>>
5766 restore_operation_disable
;
5768 if (record_full_is_used ())
5769 restore_operation_disable
.emplace
5770 (record_full_gdb_operation_disable_set ());
5772 regcache_write_pc (regcache
,
5773 ecs
->event_thread
->suspend
.stop_pc
+ decr_pc
);
5778 /* A delayed software breakpoint event. Ignore the trap. */
5780 fprintf_unfiltered (gdb_stdlog
,
5781 "infrun: delayed software breakpoint "
5782 "trap, ignoring\n");
5787 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
5788 has since been removed. */
5789 if (random_signal
&& target_stopped_by_hw_breakpoint ())
5791 /* A delayed hardware breakpoint event. Ignore the trap. */
5793 fprintf_unfiltered (gdb_stdlog
,
5794 "infrun: delayed hardware breakpoint/watchpoint "
5795 "trap, ignoring\n");
5799 /* If not, perhaps stepping/nexting can. */
5801 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5802 && currently_stepping (ecs
->event_thread
));
5804 /* Perhaps the thread hit a single-step breakpoint of _another_
5805 thread. Single-step breakpoints are transparent to the
5806 breakpoints module. */
5808 random_signal
= !ecs
->hit_singlestep_breakpoint
;
5810 /* No? Perhaps we got a moribund watchpoint. */
5812 random_signal
= !stopped_by_watchpoint
;
5814 /* Always stop if the user explicitly requested this thread to
5816 if (ecs
->event_thread
->stop_requested
)
5820 fprintf_unfiltered (gdb_stdlog
, "infrun: user-requested stop\n");
5823 /* For the program's own signals, act according to
5824 the signal handling tables. */
5828 /* Signal not for debugging purposes. */
5829 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
5830 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
5833 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
5834 gdb_signal_to_symbol_string (stop_signal
));
5836 stopped_by_random_signal
= 1;
5838 /* Always stop on signals if we're either just gaining control
5839 of the program, or the user explicitly requested this thread
5840 to remain stopped. */
5841 if (stop_soon
!= NO_STOP_QUIETLY
5842 || ecs
->event_thread
->stop_requested
5844 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
5850 /* Notify observers the signal has "handle print" set. Note we
5851 returned early above if stopping; normal_stop handles the
5852 printing in that case. */
5853 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
5855 /* The signal table tells us to print about this signal. */
5856 target_terminal::ours_for_output ();
5857 gdb::observers::signal_received
.notify (ecs
->event_thread
->suspend
.stop_signal
);
5858 target_terminal::inferior ();
5861 /* Clear the signal if it should not be passed. */
5862 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
5863 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5865 if (ecs
->event_thread
->prev_pc
== ecs
->event_thread
->suspend
.stop_pc
5866 && ecs
->event_thread
->control
.trap_expected
5867 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
5869 /* We were just starting a new sequence, attempting to
5870 single-step off of a breakpoint and expecting a SIGTRAP.
5871 Instead this signal arrives. This signal will take us out
5872 of the stepping range so GDB needs to remember to, when
5873 the signal handler returns, resume stepping off that
5875 /* To simplify things, "continue" is forced to use the same
5876 code paths as single-step - set a breakpoint at the
5877 signal return address and then, once hit, step off that
5880 fprintf_unfiltered (gdb_stdlog
,
5881 "infrun: signal arrived while stepping over "
5884 insert_hp_step_resume_breakpoint_at_frame (frame
);
5885 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
5886 /* Reset trap_expected to ensure breakpoints are re-inserted. */
5887 ecs
->event_thread
->control
.trap_expected
= 0;
5889 /* If we were nexting/stepping some other thread, switch to
5890 it, so that we don't continue it, losing control. */
5891 if (!switch_back_to_stepped_thread (ecs
))
5896 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
5897 && (pc_in_thread_step_range (ecs
->event_thread
->suspend
.stop_pc
,
5899 || ecs
->event_thread
->control
.step_range_end
== 1)
5900 && frame_id_eq (get_stack_frame_id (frame
),
5901 ecs
->event_thread
->control
.step_stack_frame_id
)
5902 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
5904 /* The inferior is about to take a signal that will take it
5905 out of the single step range. Set a breakpoint at the
5906 current PC (which is presumably where the signal handler
5907 will eventually return) and then allow the inferior to
5910 Note that this is only needed for a signal delivered
5911 while in the single-step range. Nested signals aren't a
5912 problem as they eventually all return. */
5914 fprintf_unfiltered (gdb_stdlog
,
5915 "infrun: signal may take us out of "
5916 "single-step range\n");
5918 clear_step_over_info ();
5919 insert_hp_step_resume_breakpoint_at_frame (frame
);
5920 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
5921 /* Reset trap_expected to ensure breakpoints are re-inserted. */
5922 ecs
->event_thread
->control
.trap_expected
= 0;
5927 /* Note: step_resume_breakpoint may be non-NULL. This occures
5928 when either there's a nested signal, or when there's a
5929 pending signal enabled just as the signal handler returns
5930 (leaving the inferior at the step-resume-breakpoint without
5931 actually executing it). Either way continue until the
5932 breakpoint is really hit. */
5934 if (!switch_back_to_stepped_thread (ecs
))
5937 fprintf_unfiltered (gdb_stdlog
,
5938 "infrun: random signal, keep going\n");
5945 process_event_stop_test (ecs
);
5948 /* Come here when we've got some debug event / signal we can explain
5949 (IOW, not a random signal), and test whether it should cause a
5950 stop, or whether we should resume the inferior (transparently).
5951 E.g., could be a breakpoint whose condition evaluates false; we
5952 could be still stepping within the line; etc. */
5955 process_event_stop_test (struct execution_control_state
*ecs
)
5957 struct symtab_and_line stop_pc_sal
;
5958 struct frame_info
*frame
;
5959 struct gdbarch
*gdbarch
;
5960 CORE_ADDR jmp_buf_pc
;
5961 struct bpstat_what what
;
5963 /* Handle cases caused by hitting a breakpoint. */
5965 frame
= get_current_frame ();
5966 gdbarch
= get_frame_arch (frame
);
5968 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
5970 if (what
.call_dummy
)
5972 stop_stack_dummy
= what
.call_dummy
;
5975 /* A few breakpoint types have callbacks associated (e.g.,
5976 bp_jit_event). Run them now. */
5977 bpstat_run_callbacks (ecs
->event_thread
->control
.stop_bpstat
);
5979 /* If we hit an internal event that triggers symbol changes, the
5980 current frame will be invalidated within bpstat_what (e.g., if we
5981 hit an internal solib event). Re-fetch it. */
5982 frame
= get_current_frame ();
5983 gdbarch
= get_frame_arch (frame
);
5985 switch (what
.main_action
)
5987 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
5988 /* If we hit the breakpoint at longjmp while stepping, we
5989 install a momentary breakpoint at the target of the
5993 fprintf_unfiltered (gdb_stdlog
,
5994 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
5996 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5998 if (what
.is_longjmp
)
6000 struct value
*arg_value
;
6002 /* If we set the longjmp breakpoint via a SystemTap probe,
6003 then use it to extract the arguments. The destination PC
6004 is the third argument to the probe. */
6005 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
6008 jmp_buf_pc
= value_as_address (arg_value
);
6009 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
6011 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
6012 || !gdbarch_get_longjmp_target (gdbarch
,
6013 frame
, &jmp_buf_pc
))
6016 fprintf_unfiltered (gdb_stdlog
,
6017 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
6018 "(!gdbarch_get_longjmp_target)\n");
6023 /* Insert a breakpoint at resume address. */
6024 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
6027 check_exception_resume (ecs
, frame
);
6031 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
6033 struct frame_info
*init_frame
;
6035 /* There are several cases to consider.
6037 1. The initiating frame no longer exists. In this case we
6038 must stop, because the exception or longjmp has gone too
6041 2. The initiating frame exists, and is the same as the
6042 current frame. We stop, because the exception or longjmp
6045 3. The initiating frame exists and is different from the
6046 current frame. This means the exception or longjmp has
6047 been caught beneath the initiating frame, so keep going.
6049 4. longjmp breakpoint has been placed just to protect
6050 against stale dummy frames and user is not interested in
6051 stopping around longjmps. */
6054 fprintf_unfiltered (gdb_stdlog
,
6055 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
6057 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
6059 delete_exception_resume_breakpoint (ecs
->event_thread
);
6061 if (what
.is_longjmp
)
6063 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
6065 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
6073 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
6077 struct frame_id current_id
6078 = get_frame_id (get_current_frame ());
6079 if (frame_id_eq (current_id
,
6080 ecs
->event_thread
->initiating_frame
))
6082 /* Case 2. Fall through. */
6092 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6094 delete_step_resume_breakpoint (ecs
->event_thread
);
6096 end_stepping_range (ecs
);
6100 case BPSTAT_WHAT_SINGLE
:
6102 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
6103 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6104 /* Still need to check other stuff, at least the case where we
6105 are stepping and step out of the right range. */
6108 case BPSTAT_WHAT_STEP_RESUME
:
6110 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
6112 delete_step_resume_breakpoint (ecs
->event_thread
);
6113 if (ecs
->event_thread
->control
.proceed_to_finish
6114 && execution_direction
== EXEC_REVERSE
)
6116 struct thread_info
*tp
= ecs
->event_thread
;
6118 /* We are finishing a function in reverse, and just hit the
6119 step-resume breakpoint at the start address of the
6120 function, and we're almost there -- just need to back up
6121 by one more single-step, which should take us back to the
6123 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
6127 fill_in_stop_func (gdbarch
, ecs
);
6128 if (ecs
->event_thread
->suspend
.stop_pc
== ecs
->stop_func_start
6129 && execution_direction
== EXEC_REVERSE
)
6131 /* We are stepping over a function call in reverse, and just
6132 hit the step-resume breakpoint at the start address of
6133 the function. Go back to single-stepping, which should
6134 take us back to the function call. */
6135 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6141 case BPSTAT_WHAT_STOP_NOISY
:
6143 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
6144 stop_print_frame
= 1;
6146 /* Assume the thread stopped for a breapoint. We'll still check
6147 whether a/the breakpoint is there when the thread is next
6149 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6154 case BPSTAT_WHAT_STOP_SILENT
:
6156 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
6157 stop_print_frame
= 0;
6159 /* Assume the thread stopped for a breapoint. We'll still check
6160 whether a/the breakpoint is there when the thread is next
6162 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6166 case BPSTAT_WHAT_HP_STEP_RESUME
:
6168 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
6170 delete_step_resume_breakpoint (ecs
->event_thread
);
6171 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
6173 /* Back when the step-resume breakpoint was inserted, we
6174 were trying to single-step off a breakpoint. Go back to
6176 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6177 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6183 case BPSTAT_WHAT_KEEP_CHECKING
:
6187 /* If we stepped a permanent breakpoint and we had a high priority
6188 step-resume breakpoint for the address we stepped, but we didn't
6189 hit it, then we must have stepped into the signal handler. The
6190 step-resume was only necessary to catch the case of _not_
6191 stepping into the handler, so delete it, and fall through to
6192 checking whether the step finished. */
6193 if (ecs
->event_thread
->stepped_breakpoint
)
6195 struct breakpoint
*sr_bp
6196 = ecs
->event_thread
->control
.step_resume_breakpoint
;
6199 && sr_bp
->loc
->permanent
6200 && sr_bp
->type
== bp_hp_step_resume
6201 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
6204 fprintf_unfiltered (gdb_stdlog
,
6205 "infrun: stepped permanent breakpoint, stopped in "
6207 delete_step_resume_breakpoint (ecs
->event_thread
);
6208 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6212 /* We come here if we hit a breakpoint but should not stop for it.
6213 Possibly we also were stepping and should stop for that. So fall
6214 through and test for stepping. But, if not stepping, do not
6217 /* In all-stop mode, if we're currently stepping but have stopped in
6218 some other thread, we need to switch back to the stepped thread. */
6219 if (switch_back_to_stepped_thread (ecs
))
6222 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
6225 fprintf_unfiltered (gdb_stdlog
,
6226 "infrun: step-resume breakpoint is inserted\n");
6228 /* Having a step-resume breakpoint overrides anything
6229 else having to do with stepping commands until
6230 that breakpoint is reached. */
6235 if (ecs
->event_thread
->control
.step_range_end
== 0)
6238 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
6239 /* Likewise if we aren't even stepping. */
6244 /* Re-fetch current thread's frame in case the code above caused
6245 the frame cache to be re-initialized, making our FRAME variable
6246 a dangling pointer. */
6247 frame
= get_current_frame ();
6248 gdbarch
= get_frame_arch (frame
);
6249 fill_in_stop_func (gdbarch
, ecs
);
6251 /* If stepping through a line, keep going if still within it.
6253 Note that step_range_end is the address of the first instruction
6254 beyond the step range, and NOT the address of the last instruction
6257 Note also that during reverse execution, we may be stepping
6258 through a function epilogue and therefore must detect when
6259 the current-frame changes in the middle of a line. */
6261 if (pc_in_thread_step_range (ecs
->event_thread
->suspend
.stop_pc
,
6263 && (execution_direction
!= EXEC_REVERSE
6264 || frame_id_eq (get_frame_id (frame
),
6265 ecs
->event_thread
->control
.step_frame_id
)))
6269 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
6270 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
6271 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
6273 /* Tentatively re-enable range stepping; `resume' disables it if
6274 necessary (e.g., if we're stepping over a breakpoint or we
6275 have software watchpoints). */
6276 ecs
->event_thread
->control
.may_range_step
= 1;
6278 /* When stepping backward, stop at beginning of line range
6279 (unless it's the function entry point, in which case
6280 keep going back to the call point). */
6281 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6282 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
6283 && stop_pc
!= ecs
->stop_func_start
6284 && execution_direction
== EXEC_REVERSE
)
6285 end_stepping_range (ecs
);
6292 /* We stepped out of the stepping range. */
6294 /* If we are stepping at the source level and entered the runtime
6295 loader dynamic symbol resolution code...
6297 EXEC_FORWARD: we keep on single stepping until we exit the run
6298 time loader code and reach the callee's address.
6300 EXEC_REVERSE: we've already executed the callee (backward), and
6301 the runtime loader code is handled just like any other
6302 undebuggable function call. Now we need only keep stepping
6303 backward through the trampoline code, and that's handled further
6304 down, so there is nothing for us to do here. */
6306 if (execution_direction
!= EXEC_REVERSE
6307 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6308 && in_solib_dynsym_resolve_code (ecs
->event_thread
->suspend
.stop_pc
))
6310 CORE_ADDR pc_after_resolver
=
6311 gdbarch_skip_solib_resolver (gdbarch
,
6312 ecs
->event_thread
->suspend
.stop_pc
);
6315 fprintf_unfiltered (gdb_stdlog
,
6316 "infrun: stepped into dynsym resolve code\n");
6318 if (pc_after_resolver
)
6320 /* Set up a step-resume breakpoint at the address
6321 indicated by SKIP_SOLIB_RESOLVER. */
6322 symtab_and_line sr_sal
;
6323 sr_sal
.pc
= pc_after_resolver
;
6324 sr_sal
.pspace
= get_frame_program_space (frame
);
6326 insert_step_resume_breakpoint_at_sal (gdbarch
,
6327 sr_sal
, null_frame_id
);
6334 /* Step through an indirect branch thunk. */
6335 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6336 && gdbarch_in_indirect_branch_thunk (gdbarch
,
6337 ecs
->event_thread
->suspend
.stop_pc
))
6340 fprintf_unfiltered (gdb_stdlog
,
6341 "infrun: stepped into indirect branch thunk\n");
6346 if (ecs
->event_thread
->control
.step_range_end
!= 1
6347 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6348 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6349 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
6352 fprintf_unfiltered (gdb_stdlog
,
6353 "infrun: stepped into signal trampoline\n");
6354 /* The inferior, while doing a "step" or "next", has ended up in
6355 a signal trampoline (either by a signal being delivered or by
6356 the signal handler returning). Just single-step until the
6357 inferior leaves the trampoline (either by calling the handler
6363 /* If we're in the return path from a shared library trampoline,
6364 we want to proceed through the trampoline when stepping. */
6365 /* macro/2012-04-25: This needs to come before the subroutine
6366 call check below as on some targets return trampolines look
6367 like subroutine calls (MIPS16 return thunks). */
6368 if (gdbarch_in_solib_return_trampoline (gdbarch
,
6369 ecs
->event_thread
->suspend
.stop_pc
,
6370 ecs
->stop_func_name
)
6371 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6373 /* Determine where this trampoline returns. */
6374 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6375 CORE_ADDR real_stop_pc
6376 = gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6379 fprintf_unfiltered (gdb_stdlog
,
6380 "infrun: stepped into solib return tramp\n");
6382 /* Only proceed through if we know where it's going. */
6385 /* And put the step-breakpoint there and go until there. */
6386 symtab_and_line sr_sal
;
6387 sr_sal
.pc
= real_stop_pc
;
6388 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6389 sr_sal
.pspace
= get_frame_program_space (frame
);
6391 /* Do not specify what the fp should be when we stop since
6392 on some machines the prologue is where the new fp value
6394 insert_step_resume_breakpoint_at_sal (gdbarch
,
6395 sr_sal
, null_frame_id
);
6397 /* Restart without fiddling with the step ranges or
6404 /* Check for subroutine calls. The check for the current frame
6405 equalling the step ID is not necessary - the check of the
6406 previous frame's ID is sufficient - but it is a common case and
6407 cheaper than checking the previous frame's ID.
6409 NOTE: frame_id_eq will never report two invalid frame IDs as
6410 being equal, so to get into this block, both the current and
6411 previous frame must have valid frame IDs. */
6412 /* The outer_frame_id check is a heuristic to detect stepping
6413 through startup code. If we step over an instruction which
6414 sets the stack pointer from an invalid value to a valid value,
6415 we may detect that as a subroutine call from the mythical
6416 "outermost" function. This could be fixed by marking
6417 outermost frames as !stack_p,code_p,special_p. Then the
6418 initial outermost frame, before sp was valid, would
6419 have code_addr == &_start. See the comment in frame_id_eq
6421 if (!frame_id_eq (get_stack_frame_id (frame
),
6422 ecs
->event_thread
->control
.step_stack_frame_id
)
6423 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6424 ecs
->event_thread
->control
.step_stack_frame_id
)
6425 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
6427 || (ecs
->event_thread
->control
.step_start_function
6428 != find_pc_function (ecs
->event_thread
->suspend
.stop_pc
)))))
6430 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6431 CORE_ADDR real_stop_pc
;
6434 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
6436 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
6438 /* I presume that step_over_calls is only 0 when we're
6439 supposed to be stepping at the assembly language level
6440 ("stepi"). Just stop. */
6441 /* And this works the same backward as frontward. MVS */
6442 end_stepping_range (ecs
);
6446 /* Reverse stepping through solib trampolines. */
6448 if (execution_direction
== EXEC_REVERSE
6449 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6450 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6451 || (ecs
->stop_func_start
== 0
6452 && in_solib_dynsym_resolve_code (stop_pc
))))
6454 /* Any solib trampoline code can be handled in reverse
6455 by simply continuing to single-step. We have already
6456 executed the solib function (backwards), and a few
6457 steps will take us back through the trampoline to the
6463 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6465 /* We're doing a "next".
6467 Normal (forward) execution: set a breakpoint at the
6468 callee's return address (the address at which the caller
6471 Reverse (backward) execution. set the step-resume
6472 breakpoint at the start of the function that we just
6473 stepped into (backwards), and continue to there. When we
6474 get there, we'll need to single-step back to the caller. */
6476 if (execution_direction
== EXEC_REVERSE
)
6478 /* If we're already at the start of the function, we've either
6479 just stepped backward into a single instruction function,
6480 or stepped back out of a signal handler to the first instruction
6481 of the function. Just keep going, which will single-step back
6483 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
6485 /* Normal function call return (static or dynamic). */
6486 symtab_and_line sr_sal
;
6487 sr_sal
.pc
= ecs
->stop_func_start
;
6488 sr_sal
.pspace
= get_frame_program_space (frame
);
6489 insert_step_resume_breakpoint_at_sal (gdbarch
,
6490 sr_sal
, null_frame_id
);
6494 insert_step_resume_breakpoint_at_caller (frame
);
6500 /* If we are in a function call trampoline (a stub between the
6501 calling routine and the real function), locate the real
6502 function. That's what tells us (a) whether we want to step
6503 into it at all, and (b) what prologue we want to run to the
6504 end of, if we do step into it. */
6505 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
6506 if (real_stop_pc
== 0)
6507 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6508 if (real_stop_pc
!= 0)
6509 ecs
->stop_func_start
= real_stop_pc
;
6511 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
6513 symtab_and_line sr_sal
;
6514 sr_sal
.pc
= ecs
->stop_func_start
;
6515 sr_sal
.pspace
= get_frame_program_space (frame
);
6517 insert_step_resume_breakpoint_at_sal (gdbarch
,
6518 sr_sal
, null_frame_id
);
6523 /* If we have line number information for the function we are
6524 thinking of stepping into and the function isn't on the skip
6527 If there are several symtabs at that PC (e.g. with include
6528 files), just want to know whether *any* of them have line
6529 numbers. find_pc_line handles this. */
6531 struct symtab_and_line tmp_sal
;
6533 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
6534 if (tmp_sal
.line
!= 0
6535 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
6538 if (execution_direction
== EXEC_REVERSE
)
6539 handle_step_into_function_backward (gdbarch
, ecs
);
6541 handle_step_into_function (gdbarch
, ecs
);
6546 /* If we have no line number and the step-stop-if-no-debug is
6547 set, we stop the step so that the user has a chance to switch
6548 in assembly mode. */
6549 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6550 && step_stop_if_no_debug
)
6552 end_stepping_range (ecs
);
6556 if (execution_direction
== EXEC_REVERSE
)
6558 /* If we're already at the start of the function, we've either just
6559 stepped backward into a single instruction function without line
6560 number info, or stepped back out of a signal handler to the first
6561 instruction of the function without line number info. Just keep
6562 going, which will single-step back to the caller. */
6563 if (ecs
->stop_func_start
!= stop_pc
)
6565 /* Set a breakpoint at callee's start address.
6566 From there we can step once and be back in the caller. */
6567 symtab_and_line sr_sal
;
6568 sr_sal
.pc
= ecs
->stop_func_start
;
6569 sr_sal
.pspace
= get_frame_program_space (frame
);
6570 insert_step_resume_breakpoint_at_sal (gdbarch
,
6571 sr_sal
, null_frame_id
);
6575 /* Set a breakpoint at callee's return address (the address
6576 at which the caller will resume). */
6577 insert_step_resume_breakpoint_at_caller (frame
);
6583 /* Reverse stepping through solib trampolines. */
6585 if (execution_direction
== EXEC_REVERSE
6586 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6588 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6590 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6591 || (ecs
->stop_func_start
== 0
6592 && in_solib_dynsym_resolve_code (stop_pc
)))
6594 /* Any solib trampoline code can be handled in reverse
6595 by simply continuing to single-step. We have already
6596 executed the solib function (backwards), and a few
6597 steps will take us back through the trampoline to the
6602 else if (in_solib_dynsym_resolve_code (stop_pc
))
6604 /* Stepped backward into the solib dynsym resolver.
6605 Set a breakpoint at its start and continue, then
6606 one more step will take us out. */
6607 symtab_and_line sr_sal
;
6608 sr_sal
.pc
= ecs
->stop_func_start
;
6609 sr_sal
.pspace
= get_frame_program_space (frame
);
6610 insert_step_resume_breakpoint_at_sal (gdbarch
,
6611 sr_sal
, null_frame_id
);
6617 stop_pc_sal
= find_pc_line (ecs
->event_thread
->suspend
.stop_pc
, 0);
6619 /* NOTE: tausq/2004-05-24: This if block used to be done before all
6620 the trampoline processing logic, however, there are some trampolines
6621 that have no names, so we should do trampoline handling first. */
6622 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6623 && ecs
->stop_func_name
== NULL
6624 && stop_pc_sal
.line
== 0)
6627 fprintf_unfiltered (gdb_stdlog
,
6628 "infrun: stepped into undebuggable function\n");
6630 /* The inferior just stepped into, or returned to, an
6631 undebuggable function (where there is no debugging information
6632 and no line number corresponding to the address where the
6633 inferior stopped). Since we want to skip this kind of code,
6634 we keep going until the inferior returns from this
6635 function - unless the user has asked us not to (via
6636 set step-mode) or we no longer know how to get back
6637 to the call site. */
6638 if (step_stop_if_no_debug
6639 || !frame_id_p (frame_unwind_caller_id (frame
)))
6641 /* If we have no line number and the step-stop-if-no-debug
6642 is set, we stop the step so that the user has a chance to
6643 switch in assembly mode. */
6644 end_stepping_range (ecs
);
6649 /* Set a breakpoint at callee's return address (the address
6650 at which the caller will resume). */
6651 insert_step_resume_breakpoint_at_caller (frame
);
6657 if (ecs
->event_thread
->control
.step_range_end
== 1)
6659 /* It is stepi or nexti. We always want to stop stepping after
6662 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
6663 end_stepping_range (ecs
);
6667 if (stop_pc_sal
.line
== 0)
6669 /* We have no line number information. That means to stop
6670 stepping (does this always happen right after one instruction,
6671 when we do "s" in a function with no line numbers,
6672 or can this happen as a result of a return or longjmp?). */
6674 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
6675 end_stepping_range (ecs
);
6679 /* Look for "calls" to inlined functions, part one. If the inline
6680 frame machinery detected some skipped call sites, we have entered
6681 a new inline function. */
6683 if (frame_id_eq (get_frame_id (get_current_frame ()),
6684 ecs
->event_thread
->control
.step_frame_id
)
6685 && inline_skipped_frames (ecs
->event_thread
))
6688 fprintf_unfiltered (gdb_stdlog
,
6689 "infrun: stepped into inlined function\n");
6691 symtab_and_line call_sal
= find_frame_sal (get_current_frame ());
6693 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
6695 /* For "step", we're going to stop. But if the call site
6696 for this inlined function is on the same source line as
6697 we were previously stepping, go down into the function
6698 first. Otherwise stop at the call site. */
6700 if (call_sal
.line
== ecs
->event_thread
->current_line
6701 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6702 step_into_inline_frame (ecs
->event_thread
);
6704 end_stepping_range (ecs
);
6709 /* For "next", we should stop at the call site if it is on a
6710 different source line. Otherwise continue through the
6711 inlined function. */
6712 if (call_sal
.line
== ecs
->event_thread
->current_line
6713 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6716 end_stepping_range (ecs
);
6721 /* Look for "calls" to inlined functions, part two. If we are still
6722 in the same real function we were stepping through, but we have
6723 to go further up to find the exact frame ID, we are stepping
6724 through a more inlined call beyond its call site. */
6726 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
6727 && !frame_id_eq (get_frame_id (get_current_frame ()),
6728 ecs
->event_thread
->control
.step_frame_id
)
6729 && stepped_in_from (get_current_frame (),
6730 ecs
->event_thread
->control
.step_frame_id
))
6733 fprintf_unfiltered (gdb_stdlog
,
6734 "infrun: stepping through inlined function\n");
6736 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6739 end_stepping_range (ecs
);
6743 if ((ecs
->event_thread
->suspend
.stop_pc
== stop_pc_sal
.pc
)
6744 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
6745 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
6747 /* We are at the start of a different line. So stop. Note that
6748 we don't stop if we step into the middle of a different line.
6749 That is said to make things like for (;;) statements work
6752 fprintf_unfiltered (gdb_stdlog
,
6753 "infrun: stepped to a different line\n");
6754 end_stepping_range (ecs
);
6758 /* We aren't done stepping.
6760 Optimize by setting the stepping range to the line.
6761 (We might not be in the original line, but if we entered a
6762 new line in mid-statement, we continue stepping. This makes
6763 things like for(;;) statements work better.) */
6765 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
6766 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
6767 ecs
->event_thread
->control
.may_range_step
= 1;
6768 set_step_info (frame
, stop_pc_sal
);
6771 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
6775 /* In all-stop mode, if we're currently stepping but have stopped in
6776 some other thread, we may need to switch back to the stepped
6777 thread. Returns true we set the inferior running, false if we left
6778 it stopped (and the event needs further processing). */
6781 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
6783 if (!target_is_non_stop_p ())
6785 struct thread_info
*stepping_thread
;
6787 /* If any thread is blocked on some internal breakpoint, and we
6788 simply need to step over that breakpoint to get it going
6789 again, do that first. */
6791 /* However, if we see an event for the stepping thread, then we
6792 know all other threads have been moved past their breakpoints
6793 already. Let the caller check whether the step is finished,
6794 etc., before deciding to move it past a breakpoint. */
6795 if (ecs
->event_thread
->control
.step_range_end
!= 0)
6798 /* Check if the current thread is blocked on an incomplete
6799 step-over, interrupted by a random signal. */
6800 if (ecs
->event_thread
->control
.trap_expected
6801 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
6805 fprintf_unfiltered (gdb_stdlog
,
6806 "infrun: need to finish step-over of [%s]\n",
6807 target_pid_to_str (ecs
->event_thread
->ptid
).c_str ());
6813 /* Check if the current thread is blocked by a single-step
6814 breakpoint of another thread. */
6815 if (ecs
->hit_singlestep_breakpoint
)
6819 fprintf_unfiltered (gdb_stdlog
,
6820 "infrun: need to step [%s] over single-step "
6822 target_pid_to_str (ecs
->ptid
).c_str ());
6828 /* If this thread needs yet another step-over (e.g., stepping
6829 through a delay slot), do it first before moving on to
6831 if (thread_still_needs_step_over (ecs
->event_thread
))
6835 fprintf_unfiltered (gdb_stdlog
,
6836 "infrun: thread [%s] still needs step-over\n",
6837 target_pid_to_str (ecs
->event_thread
->ptid
).c_str ());
6843 /* If scheduler locking applies even if not stepping, there's no
6844 need to walk over threads. Above we've checked whether the
6845 current thread is stepping. If some other thread not the
6846 event thread is stepping, then it must be that scheduler
6847 locking is not in effect. */
6848 if (schedlock_applies (ecs
->event_thread
))
6851 /* Otherwise, we no longer expect a trap in the current thread.
6852 Clear the trap_expected flag before switching back -- this is
6853 what keep_going does as well, if we call it. */
6854 ecs
->event_thread
->control
.trap_expected
= 0;
6856 /* Likewise, clear the signal if it should not be passed. */
6857 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
6858 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6860 /* Do all pending step-overs before actually proceeding with
6862 if (start_step_over ())
6864 prepare_to_wait (ecs
);
6868 /* Look for the stepping/nexting thread. */
6869 stepping_thread
= NULL
;
6871 for (thread_info
*tp
: all_non_exited_threads ())
6873 /* Ignore threads of processes the caller is not
6876 && tp
->ptid
.pid () != ecs
->ptid
.pid ())
6879 /* When stepping over a breakpoint, we lock all threads
6880 except the one that needs to move past the breakpoint.
6881 If a non-event thread has this set, the "incomplete
6882 step-over" check above should have caught it earlier. */
6883 if (tp
->control
.trap_expected
)
6885 internal_error (__FILE__
, __LINE__
,
6886 "[%s] has inconsistent state: "
6887 "trap_expected=%d\n",
6888 target_pid_to_str (tp
->ptid
).c_str (),
6889 tp
->control
.trap_expected
);
6892 /* Did we find the stepping thread? */
6893 if (tp
->control
.step_range_end
)
6895 /* Yep. There should only one though. */
6896 gdb_assert (stepping_thread
== NULL
);
6898 /* The event thread is handled at the top, before we
6900 gdb_assert (tp
!= ecs
->event_thread
);
6902 /* If some thread other than the event thread is
6903 stepping, then scheduler locking can't be in effect,
6904 otherwise we wouldn't have resumed the current event
6905 thread in the first place. */
6906 gdb_assert (!schedlock_applies (tp
));
6908 stepping_thread
= tp
;
6912 if (stepping_thread
!= NULL
)
6915 fprintf_unfiltered (gdb_stdlog
,
6916 "infrun: switching back to stepped thread\n");
6918 if (keep_going_stepped_thread (stepping_thread
))
6920 prepare_to_wait (ecs
);
6929 /* Set a previously stepped thread back to stepping. Returns true on
6930 success, false if the resume is not possible (e.g., the thread
6934 keep_going_stepped_thread (struct thread_info
*tp
)
6936 struct frame_info
*frame
;
6937 struct execution_control_state ecss
;
6938 struct execution_control_state
*ecs
= &ecss
;
6940 /* If the stepping thread exited, then don't try to switch back and
6941 resume it, which could fail in several different ways depending
6942 on the target. Instead, just keep going.
6944 We can find a stepping dead thread in the thread list in two
6947 - The target supports thread exit events, and when the target
6948 tries to delete the thread from the thread list, inferior_ptid
6949 pointed at the exiting thread. In such case, calling
6950 delete_thread does not really remove the thread from the list;
6951 instead, the thread is left listed, with 'exited' state.
6953 - The target's debug interface does not support thread exit
6954 events, and so we have no idea whatsoever if the previously
6955 stepping thread is still alive. For that reason, we need to
6956 synchronously query the target now. */
6958 if (tp
->state
== THREAD_EXITED
|| !target_thread_alive (tp
->ptid
))
6961 fprintf_unfiltered (gdb_stdlog
,
6962 "infrun: not resuming previously "
6963 "stepped thread, it has vanished\n");
6970 fprintf_unfiltered (gdb_stdlog
,
6971 "infrun: resuming previously stepped thread\n");
6973 reset_ecs (ecs
, tp
);
6974 switch_to_thread (tp
);
6976 tp
->suspend
.stop_pc
= regcache_read_pc (get_thread_regcache (tp
));
6977 frame
= get_current_frame ();
6979 /* If the PC of the thread we were trying to single-step has
6980 changed, then that thread has trapped or been signaled, but the
6981 event has not been reported to GDB yet. Re-poll the target
6982 looking for this particular thread's event (i.e. temporarily
6983 enable schedlock) by:
6985 - setting a break at the current PC
6986 - resuming that particular thread, only (by setting trap
6989 This prevents us continuously moving the single-step breakpoint
6990 forward, one instruction at a time, overstepping. */
6992 if (tp
->suspend
.stop_pc
!= tp
->prev_pc
)
6997 fprintf_unfiltered (gdb_stdlog
,
6998 "infrun: expected thread advanced also (%s -> %s)\n",
6999 paddress (target_gdbarch (), tp
->prev_pc
),
7000 paddress (target_gdbarch (), tp
->suspend
.stop_pc
));
7002 /* Clear the info of the previous step-over, as it's no longer
7003 valid (if the thread was trying to step over a breakpoint, it
7004 has already succeeded). It's what keep_going would do too,
7005 if we called it. Do this before trying to insert the sss
7006 breakpoint, otherwise if we were previously trying to step
7007 over this exact address in another thread, the breakpoint is
7009 clear_step_over_info ();
7010 tp
->control
.trap_expected
= 0;
7012 insert_single_step_breakpoint (get_frame_arch (frame
),
7013 get_frame_address_space (frame
),
7014 tp
->suspend
.stop_pc
);
7017 resume_ptid
= internal_resume_ptid (tp
->control
.stepping_command
);
7018 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
7023 fprintf_unfiltered (gdb_stdlog
,
7024 "infrun: expected thread still hasn't advanced\n");
7026 keep_going_pass_signal (ecs
);
7031 /* Is thread TP in the middle of (software or hardware)
7032 single-stepping? (Note the result of this function must never be
7033 passed directly as target_resume's STEP parameter.) */
7036 currently_stepping (struct thread_info
*tp
)
7038 return ((tp
->control
.step_range_end
7039 && tp
->control
.step_resume_breakpoint
== NULL
)
7040 || tp
->control
.trap_expected
7041 || tp
->stepped_breakpoint
7042 || bpstat_should_step ());
7045 /* Inferior has stepped into a subroutine call with source code that
7046 we should not step over. Do step to the first line of code in
7050 handle_step_into_function (struct gdbarch
*gdbarch
,
7051 struct execution_control_state
*ecs
)
7053 fill_in_stop_func (gdbarch
, ecs
);
7055 compunit_symtab
*cust
7056 = find_pc_compunit_symtab (ecs
->event_thread
->suspend
.stop_pc
);
7057 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7058 ecs
->stop_func_start
7059 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7061 symtab_and_line stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7062 /* Use the step_resume_break to step until the end of the prologue,
7063 even if that involves jumps (as it seems to on the vax under
7065 /* If the prologue ends in the middle of a source line, continue to
7066 the end of that source line (if it is still within the function).
7067 Otherwise, just go to end of prologue. */
7068 if (stop_func_sal
.end
7069 && stop_func_sal
.pc
!= ecs
->stop_func_start
7070 && stop_func_sal
.end
< ecs
->stop_func_end
)
7071 ecs
->stop_func_start
= stop_func_sal
.end
;
7073 /* Architectures which require breakpoint adjustment might not be able
7074 to place a breakpoint at the computed address. If so, the test
7075 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7076 ecs->stop_func_start to an address at which a breakpoint may be
7077 legitimately placed.
7079 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7080 made, GDB will enter an infinite loop when stepping through
7081 optimized code consisting of VLIW instructions which contain
7082 subinstructions corresponding to different source lines. On
7083 FR-V, it's not permitted to place a breakpoint on any but the
7084 first subinstruction of a VLIW instruction. When a breakpoint is
7085 set, GDB will adjust the breakpoint address to the beginning of
7086 the VLIW instruction. Thus, we need to make the corresponding
7087 adjustment here when computing the stop address. */
7089 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
7091 ecs
->stop_func_start
7092 = gdbarch_adjust_breakpoint_address (gdbarch
,
7093 ecs
->stop_func_start
);
7096 if (ecs
->stop_func_start
== ecs
->event_thread
->suspend
.stop_pc
)
7098 /* We are already there: stop now. */
7099 end_stepping_range (ecs
);
7104 /* Put the step-breakpoint there and go until there. */
7105 symtab_and_line sr_sal
;
7106 sr_sal
.pc
= ecs
->stop_func_start
;
7107 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
7108 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
7110 /* Do not specify what the fp should be when we stop since on
7111 some machines the prologue is where the new fp value is
7113 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
7115 /* And make sure stepping stops right away then. */
7116 ecs
->event_thread
->control
.step_range_end
7117 = ecs
->event_thread
->control
.step_range_start
;
7122 /* Inferior has stepped backward into a subroutine call with source
7123 code that we should not step over. Do step to the beginning of the
7124 last line of code in it. */
7127 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
7128 struct execution_control_state
*ecs
)
7130 struct compunit_symtab
*cust
;
7131 struct symtab_and_line stop_func_sal
;
7133 fill_in_stop_func (gdbarch
, ecs
);
7135 cust
= find_pc_compunit_symtab (ecs
->event_thread
->suspend
.stop_pc
);
7136 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7137 ecs
->stop_func_start
7138 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7140 stop_func_sal
= find_pc_line (ecs
->event_thread
->suspend
.stop_pc
, 0);
7142 /* OK, we're just going to keep stepping here. */
7143 if (stop_func_sal
.pc
== ecs
->event_thread
->suspend
.stop_pc
)
7145 /* We're there already. Just stop stepping now. */
7146 end_stepping_range (ecs
);
7150 /* Else just reset the step range and keep going.
7151 No step-resume breakpoint, they don't work for
7152 epilogues, which can have multiple entry paths. */
7153 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
7154 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
7160 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7161 This is used to both functions and to skip over code. */
7164 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
7165 struct symtab_and_line sr_sal
,
7166 struct frame_id sr_id
,
7167 enum bptype sr_type
)
7169 /* There should never be more than one step-resume or longjmp-resume
7170 breakpoint per thread, so we should never be setting a new
7171 step_resume_breakpoint when one is already active. */
7172 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
7173 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
7176 fprintf_unfiltered (gdb_stdlog
,
7177 "infrun: inserting step-resume breakpoint at %s\n",
7178 paddress (gdbarch
, sr_sal
.pc
));
7180 inferior_thread ()->control
.step_resume_breakpoint
7181 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
).release ();
7185 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
7186 struct symtab_and_line sr_sal
,
7187 struct frame_id sr_id
)
7189 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
7194 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7195 This is used to skip a potential signal handler.
7197 This is called with the interrupted function's frame. The signal
7198 handler, when it returns, will resume the interrupted function at
7202 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
7204 gdb_assert (return_frame
!= NULL
);
7206 struct gdbarch
*gdbarch
= get_frame_arch (return_frame
);
7208 symtab_and_line sr_sal
;
7209 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
7210 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7211 sr_sal
.pspace
= get_frame_program_space (return_frame
);
7213 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
7214 get_stack_frame_id (return_frame
),
7218 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7219 is used to skip a function after stepping into it (for "next" or if
7220 the called function has no debugging information).
7222 The current function has almost always been reached by single
7223 stepping a call or return instruction. NEXT_FRAME belongs to the
7224 current function, and the breakpoint will be set at the caller's
7227 This is a separate function rather than reusing
7228 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7229 get_prev_frame, which may stop prematurely (see the implementation
7230 of frame_unwind_caller_id for an example). */
7233 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
7235 /* We shouldn't have gotten here if we don't know where the call site
7237 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
7239 struct gdbarch
*gdbarch
= frame_unwind_caller_arch (next_frame
);
7241 symtab_and_line sr_sal
;
7242 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
7243 frame_unwind_caller_pc (next_frame
));
7244 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7245 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
7247 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
7248 frame_unwind_caller_id (next_frame
));
7251 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7252 new breakpoint at the target of a jmp_buf. The handling of
7253 longjmp-resume uses the same mechanisms used for handling
7254 "step-resume" breakpoints. */
7257 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
7259 /* There should never be more than one longjmp-resume breakpoint per
7260 thread, so we should never be setting a new
7261 longjmp_resume_breakpoint when one is already active. */
7262 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
7265 fprintf_unfiltered (gdb_stdlog
,
7266 "infrun: inserting longjmp-resume breakpoint at %s\n",
7267 paddress (gdbarch
, pc
));
7269 inferior_thread ()->control
.exception_resume_breakpoint
=
7270 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
).release ();
7273 /* Insert an exception resume breakpoint. TP is the thread throwing
7274 the exception. The block B is the block of the unwinder debug hook
7275 function. FRAME is the frame corresponding to the call to this
7276 function. SYM is the symbol of the function argument holding the
7277 target PC of the exception. */
7280 insert_exception_resume_breakpoint (struct thread_info
*tp
,
7281 const struct block
*b
,
7282 struct frame_info
*frame
,
7287 struct block_symbol vsym
;
7288 struct value
*value
;
7290 struct breakpoint
*bp
;
7292 vsym
= lookup_symbol_search_name (SYMBOL_SEARCH_NAME (sym
),
7294 value
= read_var_value (vsym
.symbol
, vsym
.block
, frame
);
7295 /* If the value was optimized out, revert to the old behavior. */
7296 if (! value_optimized_out (value
))
7298 handler
= value_as_address (value
);
7301 fprintf_unfiltered (gdb_stdlog
,
7302 "infrun: exception resume at %lx\n",
7303 (unsigned long) handler
);
7305 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7307 bp_exception_resume
).release ();
7309 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7312 bp
->thread
= tp
->global_num
;
7313 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7316 catch (const gdb_exception_error
&e
)
7318 /* We want to ignore errors here. */
7322 /* A helper for check_exception_resume that sets an
7323 exception-breakpoint based on a SystemTap probe. */
7326 insert_exception_resume_from_probe (struct thread_info
*tp
,
7327 const struct bound_probe
*probe
,
7328 struct frame_info
*frame
)
7330 struct value
*arg_value
;
7332 struct breakpoint
*bp
;
7334 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
7338 handler
= value_as_address (arg_value
);
7341 fprintf_unfiltered (gdb_stdlog
,
7342 "infrun: exception resume at %s\n",
7343 paddress (get_objfile_arch (probe
->objfile
),
7346 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7347 handler
, bp_exception_resume
).release ();
7348 bp
->thread
= tp
->global_num
;
7349 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7352 /* This is called when an exception has been intercepted. Check to
7353 see whether the exception's destination is of interest, and if so,
7354 set an exception resume breakpoint there. */
7357 check_exception_resume (struct execution_control_state
*ecs
,
7358 struct frame_info
*frame
)
7360 struct bound_probe probe
;
7361 struct symbol
*func
;
7363 /* First see if this exception unwinding breakpoint was set via a
7364 SystemTap probe point. If so, the probe has two arguments: the
7365 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7366 set a breakpoint there. */
7367 probe
= find_probe_by_pc (get_frame_pc (frame
));
7370 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
7374 func
= get_frame_function (frame
);
7380 const struct block
*b
;
7381 struct block_iterator iter
;
7385 /* The exception breakpoint is a thread-specific breakpoint on
7386 the unwinder's debug hook, declared as:
7388 void _Unwind_DebugHook (void *cfa, void *handler);
7390 The CFA argument indicates the frame to which control is
7391 about to be transferred. HANDLER is the destination PC.
7393 We ignore the CFA and set a temporary breakpoint at HANDLER.
7394 This is not extremely efficient but it avoids issues in gdb
7395 with computing the DWARF CFA, and it also works even in weird
7396 cases such as throwing an exception from inside a signal
7399 b
= SYMBOL_BLOCK_VALUE (func
);
7400 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
7402 if (!SYMBOL_IS_ARGUMENT (sym
))
7409 insert_exception_resume_breakpoint (ecs
->event_thread
,
7415 catch (const gdb_exception_error
&e
)
7421 stop_waiting (struct execution_control_state
*ecs
)
7424 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
7426 /* Let callers know we don't want to wait for the inferior anymore. */
7427 ecs
->wait_some_more
= 0;
7429 /* If all-stop, but the target is always in non-stop mode, stop all
7430 threads now that we're presenting the stop to the user. */
7431 if (!non_stop
&& target_is_non_stop_p ())
7432 stop_all_threads ();
7435 /* Like keep_going, but passes the signal to the inferior, even if the
7436 signal is set to nopass. */
7439 keep_going_pass_signal (struct execution_control_state
*ecs
)
7441 gdb_assert (ecs
->event_thread
->ptid
== inferior_ptid
);
7442 gdb_assert (!ecs
->event_thread
->resumed
);
7444 /* Save the pc before execution, to compare with pc after stop. */
7445 ecs
->event_thread
->prev_pc
7446 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
7448 if (ecs
->event_thread
->control
.trap_expected
)
7450 struct thread_info
*tp
= ecs
->event_thread
;
7453 fprintf_unfiltered (gdb_stdlog
,
7454 "infrun: %s has trap_expected set, "
7455 "resuming to collect trap\n",
7456 target_pid_to_str (tp
->ptid
).c_str ());
7458 /* We haven't yet gotten our trap, and either: intercepted a
7459 non-signal event (e.g., a fork); or took a signal which we
7460 are supposed to pass through to the inferior. Simply
7462 resume (ecs
->event_thread
->suspend
.stop_signal
);
7464 else if (step_over_info_valid_p ())
7466 /* Another thread is stepping over a breakpoint in-line. If
7467 this thread needs a step-over too, queue the request. In
7468 either case, this resume must be deferred for later. */
7469 struct thread_info
*tp
= ecs
->event_thread
;
7471 if (ecs
->hit_singlestep_breakpoint
7472 || thread_still_needs_step_over (tp
))
7475 fprintf_unfiltered (gdb_stdlog
,
7476 "infrun: step-over already in progress: "
7477 "step-over for %s deferred\n",
7478 target_pid_to_str (tp
->ptid
).c_str ());
7479 thread_step_over_chain_enqueue (tp
);
7484 fprintf_unfiltered (gdb_stdlog
,
7485 "infrun: step-over in progress: "
7486 "resume of %s deferred\n",
7487 target_pid_to_str (tp
->ptid
).c_str ());
7492 struct regcache
*regcache
= get_current_regcache ();
7495 step_over_what step_what
;
7497 /* Either the trap was not expected, but we are continuing
7498 anyway (if we got a signal, the user asked it be passed to
7501 We got our expected trap, but decided we should resume from
7504 We're going to run this baby now!
7506 Note that insert_breakpoints won't try to re-insert
7507 already inserted breakpoints. Therefore, we don't
7508 care if breakpoints were already inserted, or not. */
7510 /* If we need to step over a breakpoint, and we're not using
7511 displaced stepping to do so, insert all breakpoints
7512 (watchpoints, etc.) but the one we're stepping over, step one
7513 instruction, and then re-insert the breakpoint when that step
7516 step_what
= thread_still_needs_step_over (ecs
->event_thread
);
7518 remove_bp
= (ecs
->hit_singlestep_breakpoint
7519 || (step_what
& STEP_OVER_BREAKPOINT
));
7520 remove_wps
= (step_what
& STEP_OVER_WATCHPOINT
);
7522 /* We can't use displaced stepping if we need to step past a
7523 watchpoint. The instruction copied to the scratch pad would
7524 still trigger the watchpoint. */
7526 && (remove_wps
|| !use_displaced_stepping (ecs
->event_thread
)))
7528 set_step_over_info (regcache
->aspace (),
7529 regcache_read_pc (regcache
), remove_wps
,
7530 ecs
->event_thread
->global_num
);
7532 else if (remove_wps
)
7533 set_step_over_info (NULL
, 0, remove_wps
, -1);
7535 /* If we now need to do an in-line step-over, we need to stop
7536 all other threads. Note this must be done before
7537 insert_breakpoints below, because that removes the breakpoint
7538 we're about to step over, otherwise other threads could miss
7540 if (step_over_info_valid_p () && target_is_non_stop_p ())
7541 stop_all_threads ();
7543 /* Stop stepping if inserting breakpoints fails. */
7546 insert_breakpoints ();
7548 catch (const gdb_exception_error
&e
)
7550 exception_print (gdb_stderr
, e
);
7552 clear_step_over_info ();
7556 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
7558 resume (ecs
->event_thread
->suspend
.stop_signal
);
7561 prepare_to_wait (ecs
);
7564 /* Called when we should continue running the inferior, because the
7565 current event doesn't cause a user visible stop. This does the
7566 resuming part; waiting for the next event is done elsewhere. */
7569 keep_going (struct execution_control_state
*ecs
)
7571 if (ecs
->event_thread
->control
.trap_expected
7572 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
7573 ecs
->event_thread
->control
.trap_expected
= 0;
7575 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7576 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7577 keep_going_pass_signal (ecs
);
7580 /* This function normally comes after a resume, before
7581 handle_inferior_event exits. It takes care of any last bits of
7582 housekeeping, and sets the all-important wait_some_more flag. */
7585 prepare_to_wait (struct execution_control_state
*ecs
)
7588 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
7590 ecs
->wait_some_more
= 1;
7592 if (!target_is_async_p ())
7593 mark_infrun_async_event_handler ();
7596 /* We are done with the step range of a step/next/si/ni command.
7597 Called once for each n of a "step n" operation. */
7600 end_stepping_range (struct execution_control_state
*ecs
)
7602 ecs
->event_thread
->control
.stop_step
= 1;
7606 /* Several print_*_reason functions to print why the inferior has stopped.
7607 We always print something when the inferior exits, or receives a signal.
7608 The rest of the cases are dealt with later on in normal_stop and
7609 print_it_typical. Ideally there should be a call to one of these
7610 print_*_reason functions functions from handle_inferior_event each time
7611 stop_waiting is called.
7613 Note that we don't call these directly, instead we delegate that to
7614 the interpreters, through observers. Interpreters then call these
7615 with whatever uiout is right. */
7618 print_end_stepping_range_reason (struct ui_out
*uiout
)
7620 /* For CLI-like interpreters, print nothing. */
7622 if (uiout
->is_mi_like_p ())
7624 uiout
->field_string ("reason",
7625 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
7630 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7632 annotate_signalled ();
7633 if (uiout
->is_mi_like_p ())
7635 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
7636 uiout
->text ("\nProgram terminated with signal ");
7637 annotate_signal_name ();
7638 uiout
->field_string ("signal-name",
7639 gdb_signal_to_name (siggnal
));
7640 annotate_signal_name_end ();
7642 annotate_signal_string ();
7643 uiout
->field_string ("signal-meaning",
7644 gdb_signal_to_string (siggnal
));
7645 annotate_signal_string_end ();
7646 uiout
->text (".\n");
7647 uiout
->text ("The program no longer exists.\n");
7651 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
7653 struct inferior
*inf
= current_inferior ();
7654 std::string pidstr
= target_pid_to_str (ptid_t (inf
->pid
));
7656 annotate_exited (exitstatus
);
7659 if (uiout
->is_mi_like_p ())
7660 uiout
->field_string ("reason", async_reason_lookup (EXEC_ASYNC_EXITED
));
7661 uiout
->text ("[Inferior ");
7662 uiout
->text (plongest (inf
->num
));
7664 uiout
->text (pidstr
.c_str ());
7665 uiout
->text (") exited with code ");
7666 uiout
->field_fmt ("exit-code", "0%o", (unsigned int) exitstatus
);
7667 uiout
->text ("]\n");
7671 if (uiout
->is_mi_like_p ())
7673 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
7674 uiout
->text ("[Inferior ");
7675 uiout
->text (plongest (inf
->num
));
7677 uiout
->text (pidstr
.c_str ());
7678 uiout
->text (") exited normally]\n");
7682 /* Some targets/architectures can do extra processing/display of
7683 segmentation faults. E.g., Intel MPX boundary faults.
7684 Call the architecture dependent function to handle the fault. */
7687 handle_segmentation_fault (struct ui_out
*uiout
)
7689 struct regcache
*regcache
= get_current_regcache ();
7690 struct gdbarch
*gdbarch
= regcache
->arch ();
7692 if (gdbarch_handle_segmentation_fault_p (gdbarch
))
7693 gdbarch_handle_segmentation_fault (gdbarch
, uiout
);
7697 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7699 struct thread_info
*thr
= inferior_thread ();
7703 if (uiout
->is_mi_like_p ())
7705 else if (show_thread_that_caused_stop ())
7709 uiout
->text ("\nThread ");
7710 uiout
->field_string ("thread-id", print_thread_id (thr
));
7712 name
= thr
->name
!= NULL
? thr
->name
: target_thread_name (thr
);
7715 uiout
->text (" \"");
7716 uiout
->field_string ("name", name
);
7721 uiout
->text ("\nProgram");
7723 if (siggnal
== GDB_SIGNAL_0
&& !uiout
->is_mi_like_p ())
7724 uiout
->text (" stopped");
7727 uiout
->text (" received signal ");
7728 annotate_signal_name ();
7729 if (uiout
->is_mi_like_p ())
7731 ("reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
7732 uiout
->field_string ("signal-name", gdb_signal_to_name (siggnal
));
7733 annotate_signal_name_end ();
7735 annotate_signal_string ();
7736 uiout
->field_string ("signal-meaning", gdb_signal_to_string (siggnal
));
7738 if (siggnal
== GDB_SIGNAL_SEGV
)
7739 handle_segmentation_fault (uiout
);
7741 annotate_signal_string_end ();
7743 uiout
->text (".\n");
7747 print_no_history_reason (struct ui_out
*uiout
)
7749 uiout
->text ("\nNo more reverse-execution history.\n");
7752 /* Print current location without a level number, if we have changed
7753 functions or hit a breakpoint. Print source line if we have one.
7754 bpstat_print contains the logic deciding in detail what to print,
7755 based on the event(s) that just occurred. */
7758 print_stop_location (struct target_waitstatus
*ws
)
7761 enum print_what source_flag
;
7762 int do_frame_printing
= 1;
7763 struct thread_info
*tp
= inferior_thread ();
7765 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
7769 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
7770 should) carry around the function and does (or should) use
7771 that when doing a frame comparison. */
7772 if (tp
->control
.stop_step
7773 && frame_id_eq (tp
->control
.step_frame_id
,
7774 get_frame_id (get_current_frame ()))
7775 && (tp
->control
.step_start_function
7776 == find_pc_function (tp
->suspend
.stop_pc
)))
7778 /* Finished step, just print source line. */
7779 source_flag
= SRC_LINE
;
7783 /* Print location and source line. */
7784 source_flag
= SRC_AND_LOC
;
7787 case PRINT_SRC_AND_LOC
:
7788 /* Print location and source line. */
7789 source_flag
= SRC_AND_LOC
;
7791 case PRINT_SRC_ONLY
:
7792 source_flag
= SRC_LINE
;
7795 /* Something bogus. */
7796 source_flag
= SRC_LINE
;
7797 do_frame_printing
= 0;
7800 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
7803 /* The behavior of this routine with respect to the source
7805 SRC_LINE: Print only source line
7806 LOCATION: Print only location
7807 SRC_AND_LOC: Print location and source line. */
7808 if (do_frame_printing
)
7809 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
7815 print_stop_event (struct ui_out
*uiout
, bool displays
)
7817 struct target_waitstatus last
;
7819 struct thread_info
*tp
;
7821 get_last_target_status (&last_ptid
, &last
);
7824 scoped_restore save_uiout
= make_scoped_restore (¤t_uiout
, uiout
);
7826 print_stop_location (&last
);
7828 /* Display the auto-display expressions. */
7833 tp
= inferior_thread ();
7834 if (tp
->thread_fsm
!= NULL
7835 && tp
->thread_fsm
->finished_p ())
7837 struct return_value_info
*rv
;
7839 rv
= tp
->thread_fsm
->return_value ();
7841 print_return_value (uiout
, rv
);
7848 maybe_remove_breakpoints (void)
7850 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
7852 if (remove_breakpoints ())
7854 target_terminal::ours_for_output ();
7855 printf_filtered (_("Cannot remove breakpoints because "
7856 "program is no longer writable.\nFurther "
7857 "execution is probably impossible.\n"));
7862 /* The execution context that just caused a normal stop. */
7869 DISABLE_COPY_AND_ASSIGN (stop_context
);
7871 bool changed () const;
7876 /* The event PTID. */
7880 /* If stopp for a thread event, this is the thread that caused the
7882 struct thread_info
*thread
;
7884 /* The inferior that caused the stop. */
7888 /* Initializes a new stop context. If stopped for a thread event, this
7889 takes a strong reference to the thread. */
7891 stop_context::stop_context ()
7893 stop_id
= get_stop_id ();
7894 ptid
= inferior_ptid
;
7895 inf_num
= current_inferior ()->num
;
7897 if (inferior_ptid
!= null_ptid
)
7899 /* Take a strong reference so that the thread can't be deleted
7901 thread
= inferior_thread ();
7908 /* Release a stop context previously created with save_stop_context.
7909 Releases the strong reference to the thread as well. */
7911 stop_context::~stop_context ()
7917 /* Return true if the current context no longer matches the saved stop
7921 stop_context::changed () const
7923 if (ptid
!= inferior_ptid
)
7925 if (inf_num
!= current_inferior ()->num
)
7927 if (thread
!= NULL
&& thread
->state
!= THREAD_STOPPED
)
7929 if (get_stop_id () != stop_id
)
7939 struct target_waitstatus last
;
7942 get_last_target_status (&last_ptid
, &last
);
7946 /* If an exception is thrown from this point on, make sure to
7947 propagate GDB's knowledge of the executing state to the
7948 frontend/user running state. A QUIT is an easy exception to see
7949 here, so do this before any filtered output. */
7951 gdb::optional
<scoped_finish_thread_state
> maybe_finish_thread_state
;
7954 maybe_finish_thread_state
.emplace (minus_one_ptid
);
7955 else if (last
.kind
== TARGET_WAITKIND_SIGNALLED
7956 || last
.kind
== TARGET_WAITKIND_EXITED
)
7958 /* On some targets, we may still have live threads in the
7959 inferior when we get a process exit event. E.g., for
7960 "checkpoint", when the current checkpoint/fork exits,
7961 linux-fork.c automatically switches to another fork from
7962 within target_mourn_inferior. */
7963 if (inferior_ptid
!= null_ptid
)
7964 maybe_finish_thread_state
.emplace (ptid_t (inferior_ptid
.pid ()));
7966 else if (last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
7967 maybe_finish_thread_state
.emplace (inferior_ptid
);
7969 /* As we're presenting a stop, and potentially removing breakpoints,
7970 update the thread list so we can tell whether there are threads
7971 running on the target. With target remote, for example, we can
7972 only learn about new threads when we explicitly update the thread
7973 list. Do this before notifying the interpreters about signal
7974 stops, end of stepping ranges, etc., so that the "new thread"
7975 output is emitted before e.g., "Program received signal FOO",
7976 instead of after. */
7977 update_thread_list ();
7979 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
7980 gdb::observers::signal_received
.notify (inferior_thread ()->suspend
.stop_signal
);
7982 /* As with the notification of thread events, we want to delay
7983 notifying the user that we've switched thread context until
7984 the inferior actually stops.
7986 There's no point in saying anything if the inferior has exited.
7987 Note that SIGNALLED here means "exited with a signal", not
7988 "received a signal".
7990 Also skip saying anything in non-stop mode. In that mode, as we
7991 don't want GDB to switch threads behind the user's back, to avoid
7992 races where the user is typing a command to apply to thread x,
7993 but GDB switches to thread y before the user finishes entering
7994 the command, fetch_inferior_event installs a cleanup to restore
7995 the current thread back to the thread the user had selected right
7996 after this event is handled, so we're not really switching, only
7997 informing of a stop. */
7999 && previous_inferior_ptid
!= inferior_ptid
8000 && target_has_execution
8001 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
8002 && last
.kind
!= TARGET_WAITKIND_EXITED
8003 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8005 SWITCH_THRU_ALL_UIS ()
8007 target_terminal::ours_for_output ();
8008 printf_filtered (_("[Switching to %s]\n"),
8009 target_pid_to_str (inferior_ptid
).c_str ());
8010 annotate_thread_changed ();
8012 previous_inferior_ptid
= inferior_ptid
;
8015 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
8017 SWITCH_THRU_ALL_UIS ()
8018 if (current_ui
->prompt_state
== PROMPT_BLOCKED
)
8020 target_terminal::ours_for_output ();
8021 printf_filtered (_("No unwaited-for children left.\n"));
8025 /* Note: this depends on the update_thread_list call above. */
8026 maybe_remove_breakpoints ();
8028 /* If an auto-display called a function and that got a signal,
8029 delete that auto-display to avoid an infinite recursion. */
8031 if (stopped_by_random_signal
)
8032 disable_current_display ();
8034 SWITCH_THRU_ALL_UIS ()
8036 async_enable_stdin ();
8039 /* Let the user/frontend see the threads as stopped. */
8040 maybe_finish_thread_state
.reset ();
8042 /* Select innermost stack frame - i.e., current frame is frame 0,
8043 and current location is based on that. Handle the case where the
8044 dummy call is returning after being stopped. E.g. the dummy call
8045 previously hit a breakpoint. (If the dummy call returns
8046 normally, we won't reach here.) Do this before the stop hook is
8047 run, so that it doesn't get to see the temporary dummy frame,
8048 which is not where we'll present the stop. */
8049 if (has_stack_frames ())
8051 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
8053 /* Pop the empty frame that contains the stack dummy. This
8054 also restores inferior state prior to the call (struct
8055 infcall_suspend_state). */
8056 struct frame_info
*frame
= get_current_frame ();
8058 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
8060 /* frame_pop calls reinit_frame_cache as the last thing it
8061 does which means there's now no selected frame. */
8064 select_frame (get_current_frame ());
8066 /* Set the current source location. */
8067 set_current_sal_from_frame (get_current_frame ());
8070 /* Look up the hook_stop and run it (CLI internally handles problem
8071 of stop_command's pre-hook not existing). */
8072 if (stop_command
!= NULL
)
8074 stop_context saved_context
;
8078 execute_cmd_pre_hook (stop_command
);
8080 catch (const gdb_exception
&ex
)
8082 exception_fprintf (gdb_stderr
, ex
,
8083 "Error while running hook_stop:\n");
8086 /* If the stop hook resumes the target, then there's no point in
8087 trying to notify about the previous stop; its context is
8088 gone. Likewise if the command switches thread or inferior --
8089 the observers would print a stop for the wrong
8091 if (saved_context
.changed ())
8095 /* Notify observers about the stop. This is where the interpreters
8096 print the stop event. */
8097 if (inferior_ptid
!= null_ptid
)
8098 gdb::observers::normal_stop
.notify (inferior_thread ()->control
.stop_bpstat
,
8101 gdb::observers::normal_stop
.notify (NULL
, stop_print_frame
);
8103 annotate_stopped ();
8105 if (target_has_execution
)
8107 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
8108 && last
.kind
!= TARGET_WAITKIND_EXITED
8109 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8110 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8111 Delete any breakpoint that is to be deleted at the next stop. */
8112 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
8115 /* Try to get rid of automatically added inferiors that are no
8116 longer needed. Keeping those around slows down things linearly.
8117 Note that this never removes the current inferior. */
8124 signal_stop_state (int signo
)
8126 return signal_stop
[signo
];
8130 signal_print_state (int signo
)
8132 return signal_print
[signo
];
8136 signal_pass_state (int signo
)
8138 return signal_program
[signo
];
8142 signal_cache_update (int signo
)
8146 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
8147 signal_cache_update (signo
);
8152 signal_pass
[signo
] = (signal_stop
[signo
] == 0
8153 && signal_print
[signo
] == 0
8154 && signal_program
[signo
] == 1
8155 && signal_catch
[signo
] == 0);
8159 signal_stop_update (int signo
, int state
)
8161 int ret
= signal_stop
[signo
];
8163 signal_stop
[signo
] = state
;
8164 signal_cache_update (signo
);
8169 signal_print_update (int signo
, int state
)
8171 int ret
= signal_print
[signo
];
8173 signal_print
[signo
] = state
;
8174 signal_cache_update (signo
);
8179 signal_pass_update (int signo
, int state
)
8181 int ret
= signal_program
[signo
];
8183 signal_program
[signo
] = state
;
8184 signal_cache_update (signo
);
8188 /* Update the global 'signal_catch' from INFO and notify the
8192 signal_catch_update (const unsigned int *info
)
8196 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
8197 signal_catch
[i
] = info
[i
] > 0;
8198 signal_cache_update (-1);
8199 target_pass_signals (signal_pass
);
8203 sig_print_header (void)
8205 printf_filtered (_("Signal Stop\tPrint\tPass "
8206 "to program\tDescription\n"));
8210 sig_print_info (enum gdb_signal oursig
)
8212 const char *name
= gdb_signal_to_name (oursig
);
8213 int name_padding
= 13 - strlen (name
);
8215 if (name_padding
<= 0)
8218 printf_filtered ("%s", name
);
8219 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
8220 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
8221 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
8222 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
8223 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
8226 /* Specify how various signals in the inferior should be handled. */
8229 handle_command (const char *args
, int from_tty
)
8231 int digits
, wordlen
;
8232 int sigfirst
, siglast
;
8233 enum gdb_signal oursig
;
8238 error_no_arg (_("signal to handle"));
8241 /* Allocate and zero an array of flags for which signals to handle. */
8243 const size_t nsigs
= GDB_SIGNAL_LAST
;
8244 unsigned char sigs
[nsigs
] {};
8246 /* Break the command line up into args. */
8248 gdb_argv
built_argv (args
);
8250 /* Walk through the args, looking for signal oursigs, signal names, and
8251 actions. Signal numbers and signal names may be interspersed with
8252 actions, with the actions being performed for all signals cumulatively
8253 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8255 for (char *arg
: built_argv
)
8257 wordlen
= strlen (arg
);
8258 for (digits
= 0; isdigit (arg
[digits
]); digits
++)
8262 sigfirst
= siglast
= -1;
8264 if (wordlen
>= 1 && !strncmp (arg
, "all", wordlen
))
8266 /* Apply action to all signals except those used by the
8267 debugger. Silently skip those. */
8270 siglast
= nsigs
- 1;
8272 else if (wordlen
>= 1 && !strncmp (arg
, "stop", wordlen
))
8274 SET_SIGS (nsigs
, sigs
, signal_stop
);
8275 SET_SIGS (nsigs
, sigs
, signal_print
);
8277 else if (wordlen
>= 1 && !strncmp (arg
, "ignore", wordlen
))
8279 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8281 else if (wordlen
>= 2 && !strncmp (arg
, "print", wordlen
))
8283 SET_SIGS (nsigs
, sigs
, signal_print
);
8285 else if (wordlen
>= 2 && !strncmp (arg
, "pass", wordlen
))
8287 SET_SIGS (nsigs
, sigs
, signal_program
);
8289 else if (wordlen
>= 3 && !strncmp (arg
, "nostop", wordlen
))
8291 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8293 else if (wordlen
>= 3 && !strncmp (arg
, "noignore", wordlen
))
8295 SET_SIGS (nsigs
, sigs
, signal_program
);
8297 else if (wordlen
>= 4 && !strncmp (arg
, "noprint", wordlen
))
8299 UNSET_SIGS (nsigs
, sigs
, signal_print
);
8300 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8302 else if (wordlen
>= 4 && !strncmp (arg
, "nopass", wordlen
))
8304 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8306 else if (digits
> 0)
8308 /* It is numeric. The numeric signal refers to our own
8309 internal signal numbering from target.h, not to host/target
8310 signal number. This is a feature; users really should be
8311 using symbolic names anyway, and the common ones like
8312 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8314 sigfirst
= siglast
= (int)
8315 gdb_signal_from_command (atoi (arg
));
8316 if (arg
[digits
] == '-')
8319 gdb_signal_from_command (atoi (arg
+ digits
+ 1));
8321 if (sigfirst
> siglast
)
8323 /* Bet he didn't figure we'd think of this case... */
8324 std::swap (sigfirst
, siglast
);
8329 oursig
= gdb_signal_from_name (arg
);
8330 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
8332 sigfirst
= siglast
= (int) oursig
;
8336 /* Not a number and not a recognized flag word => complain. */
8337 error (_("Unrecognized or ambiguous flag word: \"%s\"."), arg
);
8341 /* If any signal numbers or symbol names were found, set flags for
8342 which signals to apply actions to. */
8344 for (int signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
8346 switch ((enum gdb_signal
) signum
)
8348 case GDB_SIGNAL_TRAP
:
8349 case GDB_SIGNAL_INT
:
8350 if (!allsigs
&& !sigs
[signum
])
8352 if (query (_("%s is used by the debugger.\n\
8353 Are you sure you want to change it? "),
8354 gdb_signal_to_name ((enum gdb_signal
) signum
)))
8359 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8363 case GDB_SIGNAL_DEFAULT
:
8364 case GDB_SIGNAL_UNKNOWN
:
8365 /* Make sure that "all" doesn't print these. */
8374 for (int signum
= 0; signum
< nsigs
; signum
++)
8377 signal_cache_update (-1);
8378 target_pass_signals (signal_pass
);
8379 target_program_signals (signal_program
);
8383 /* Show the results. */
8384 sig_print_header ();
8385 for (; signum
< nsigs
; signum
++)
8387 sig_print_info ((enum gdb_signal
) signum
);
8394 /* Complete the "handle" command. */
8397 handle_completer (struct cmd_list_element
*ignore
,
8398 completion_tracker
&tracker
,
8399 const char *text
, const char *word
)
8401 static const char * const keywords
[] =
8415 signal_completer (ignore
, tracker
, text
, word
);
8416 complete_on_enum (tracker
, keywords
, word
, word
);
8420 gdb_signal_from_command (int num
)
8422 if (num
>= 1 && num
<= 15)
8423 return (enum gdb_signal
) num
;
8424 error (_("Only signals 1-15 are valid as numeric signals.\n\
8425 Use \"info signals\" for a list of symbolic signals."));
8428 /* Print current contents of the tables set by the handle command.
8429 It is possible we should just be printing signals actually used
8430 by the current target (but for things to work right when switching
8431 targets, all signals should be in the signal tables). */
8434 info_signals_command (const char *signum_exp
, int from_tty
)
8436 enum gdb_signal oursig
;
8438 sig_print_header ();
8442 /* First see if this is a symbol name. */
8443 oursig
= gdb_signal_from_name (signum_exp
);
8444 if (oursig
== GDB_SIGNAL_UNKNOWN
)
8446 /* No, try numeric. */
8448 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
8450 sig_print_info (oursig
);
8454 printf_filtered ("\n");
8455 /* These ugly casts brought to you by the native VAX compiler. */
8456 for (oursig
= GDB_SIGNAL_FIRST
;
8457 (int) oursig
< (int) GDB_SIGNAL_LAST
;
8458 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
8462 if (oursig
!= GDB_SIGNAL_UNKNOWN
8463 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
8464 sig_print_info (oursig
);
8467 printf_filtered (_("\nUse the \"handle\" command "
8468 "to change these tables.\n"));
8471 /* The $_siginfo convenience variable is a bit special. We don't know
8472 for sure the type of the value until we actually have a chance to
8473 fetch the data. The type can change depending on gdbarch, so it is
8474 also dependent on which thread you have selected.
8476 1. making $_siginfo be an internalvar that creates a new value on
8479 2. making the value of $_siginfo be an lval_computed value. */
8481 /* This function implements the lval_computed support for reading a
8485 siginfo_value_read (struct value
*v
)
8487 LONGEST transferred
;
8489 /* If we can access registers, so can we access $_siginfo. Likewise
8491 validate_registers_access ();
8494 target_read (current_top_target (), TARGET_OBJECT_SIGNAL_INFO
,
8496 value_contents_all_raw (v
),
8498 TYPE_LENGTH (value_type (v
)));
8500 if (transferred
!= TYPE_LENGTH (value_type (v
)))
8501 error (_("Unable to read siginfo"));
8504 /* This function implements the lval_computed support for writing a
8508 siginfo_value_write (struct value
*v
, struct value
*fromval
)
8510 LONGEST transferred
;
8512 /* If we can access registers, so can we access $_siginfo. Likewise
8514 validate_registers_access ();
8516 transferred
= target_write (current_top_target (),
8517 TARGET_OBJECT_SIGNAL_INFO
,
8519 value_contents_all_raw (fromval
),
8521 TYPE_LENGTH (value_type (fromval
)));
8523 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
8524 error (_("Unable to write siginfo"));
8527 static const struct lval_funcs siginfo_value_funcs
=
8533 /* Return a new value with the correct type for the siginfo object of
8534 the current thread using architecture GDBARCH. Return a void value
8535 if there's no object available. */
8537 static struct value
*
8538 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
8541 if (target_has_stack
8542 && inferior_ptid
!= null_ptid
8543 && gdbarch_get_siginfo_type_p (gdbarch
))
8545 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8547 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
8550 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
8554 /* infcall_suspend_state contains state about the program itself like its
8555 registers and any signal it received when it last stopped.
8556 This state must be restored regardless of how the inferior function call
8557 ends (either successfully, or after it hits a breakpoint or signal)
8558 if the program is to properly continue where it left off. */
8560 class infcall_suspend_state
8563 /* Capture state from GDBARCH, TP, and REGCACHE that must be restored
8564 once the inferior function call has finished. */
8565 infcall_suspend_state (struct gdbarch
*gdbarch
,
8566 const struct thread_info
*tp
,
8567 struct regcache
*regcache
)
8568 : m_thread_suspend (tp
->suspend
),
8569 m_registers (new readonly_detached_regcache (*regcache
))
8571 gdb::unique_xmalloc_ptr
<gdb_byte
> siginfo_data
;
8573 if (gdbarch_get_siginfo_type_p (gdbarch
))
8575 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8576 size_t len
= TYPE_LENGTH (type
);
8578 siginfo_data
.reset ((gdb_byte
*) xmalloc (len
));
8580 if (target_read (current_top_target (), TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8581 siginfo_data
.get (), 0, len
) != len
)
8583 /* Errors ignored. */
8584 siginfo_data
.reset (nullptr);
8590 m_siginfo_gdbarch
= gdbarch
;
8591 m_siginfo_data
= std::move (siginfo_data
);
8595 /* Return a pointer to the stored register state. */
8597 readonly_detached_regcache
*registers () const
8599 return m_registers
.get ();
8602 /* Restores the stored state into GDBARCH, TP, and REGCACHE. */
8604 void restore (struct gdbarch
*gdbarch
,
8605 struct thread_info
*tp
,
8606 struct regcache
*regcache
) const
8608 tp
->suspend
= m_thread_suspend
;
8610 if (m_siginfo_gdbarch
== gdbarch
)
8612 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8614 /* Errors ignored. */
8615 target_write (current_top_target (), TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8616 m_siginfo_data
.get (), 0, TYPE_LENGTH (type
));
8619 /* The inferior can be gone if the user types "print exit(0)"
8620 (and perhaps other times). */
8621 if (target_has_execution
)
8622 /* NB: The register write goes through to the target. */
8623 regcache
->restore (registers ());
8627 /* How the current thread stopped before the inferior function call was
8629 struct thread_suspend_state m_thread_suspend
;
8631 /* The registers before the inferior function call was executed. */
8632 std::unique_ptr
<readonly_detached_regcache
> m_registers
;
8634 /* Format of SIGINFO_DATA or NULL if it is not present. */
8635 struct gdbarch
*m_siginfo_gdbarch
= nullptr;
8637 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
8638 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
8639 content would be invalid. */
8640 gdb::unique_xmalloc_ptr
<gdb_byte
> m_siginfo_data
;
8643 infcall_suspend_state_up
8644 save_infcall_suspend_state ()
8646 struct thread_info
*tp
= inferior_thread ();
8647 struct regcache
*regcache
= get_current_regcache ();
8648 struct gdbarch
*gdbarch
= regcache
->arch ();
8650 infcall_suspend_state_up inf_state
8651 (new struct infcall_suspend_state (gdbarch
, tp
, regcache
));
8653 /* Having saved the current state, adjust the thread state, discarding
8654 any stop signal information. The stop signal is not useful when
8655 starting an inferior function call, and run_inferior_call will not use
8656 the signal due to its `proceed' call with GDB_SIGNAL_0. */
8657 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
8662 /* Restore inferior session state to INF_STATE. */
8665 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8667 struct thread_info
*tp
= inferior_thread ();
8668 struct regcache
*regcache
= get_current_regcache ();
8669 struct gdbarch
*gdbarch
= regcache
->arch ();
8671 inf_state
->restore (gdbarch
, tp
, regcache
);
8672 discard_infcall_suspend_state (inf_state
);
8676 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8681 readonly_detached_regcache
*
8682 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
8684 return inf_state
->registers ();
8687 /* infcall_control_state contains state regarding gdb's control of the
8688 inferior itself like stepping control. It also contains session state like
8689 the user's currently selected frame. */
8691 struct infcall_control_state
8693 struct thread_control_state thread_control
;
8694 struct inferior_control_state inferior_control
;
8697 enum stop_stack_kind stop_stack_dummy
= STOP_NONE
;
8698 int stopped_by_random_signal
= 0;
8700 /* ID if the selected frame when the inferior function call was made. */
8701 struct frame_id selected_frame_id
{};
8704 /* Save all of the information associated with the inferior<==>gdb
8707 infcall_control_state_up
8708 save_infcall_control_state ()
8710 infcall_control_state_up
inf_status (new struct infcall_control_state
);
8711 struct thread_info
*tp
= inferior_thread ();
8712 struct inferior
*inf
= current_inferior ();
8714 inf_status
->thread_control
= tp
->control
;
8715 inf_status
->inferior_control
= inf
->control
;
8717 tp
->control
.step_resume_breakpoint
= NULL
;
8718 tp
->control
.exception_resume_breakpoint
= NULL
;
8720 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
8721 chain. If caller's caller is walking the chain, they'll be happier if we
8722 hand them back the original chain when restore_infcall_control_state is
8724 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
8727 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
8728 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
8730 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
8736 restore_selected_frame (const frame_id
&fid
)
8738 frame_info
*frame
= frame_find_by_id (fid
);
8740 /* If inf_status->selected_frame_id is NULL, there was no previously
8744 warning (_("Unable to restore previously selected frame."));
8748 select_frame (frame
);
8751 /* Restore inferior session state to INF_STATUS. */
8754 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
8756 struct thread_info
*tp
= inferior_thread ();
8757 struct inferior
*inf
= current_inferior ();
8759 if (tp
->control
.step_resume_breakpoint
)
8760 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
8762 if (tp
->control
.exception_resume_breakpoint
)
8763 tp
->control
.exception_resume_breakpoint
->disposition
8764 = disp_del_at_next_stop
;
8766 /* Handle the bpstat_copy of the chain. */
8767 bpstat_clear (&tp
->control
.stop_bpstat
);
8769 tp
->control
= inf_status
->thread_control
;
8770 inf
->control
= inf_status
->inferior_control
;
8773 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
8774 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
8776 if (target_has_stack
)
8778 /* The point of the try/catch is that if the stack is clobbered,
8779 walking the stack might encounter a garbage pointer and
8780 error() trying to dereference it. */
8783 restore_selected_frame (inf_status
->selected_frame_id
);
8785 catch (const gdb_exception_error
&ex
)
8787 exception_fprintf (gdb_stderr
, ex
,
8788 "Unable to restore previously selected frame:\n");
8789 /* Error in restoring the selected frame. Select the
8791 select_frame (get_current_frame ());
8799 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
8801 if (inf_status
->thread_control
.step_resume_breakpoint
)
8802 inf_status
->thread_control
.step_resume_breakpoint
->disposition
8803 = disp_del_at_next_stop
;
8805 if (inf_status
->thread_control
.exception_resume_breakpoint
)
8806 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
8807 = disp_del_at_next_stop
;
8809 /* See save_infcall_control_state for info on stop_bpstat. */
8810 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
8818 clear_exit_convenience_vars (void)
8820 clear_internalvar (lookup_internalvar ("_exitsignal"));
8821 clear_internalvar (lookup_internalvar ("_exitcode"));
8825 /* User interface for reverse debugging:
8826 Set exec-direction / show exec-direction commands
8827 (returns error unless target implements to_set_exec_direction method). */
8829 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
8830 static const char exec_forward
[] = "forward";
8831 static const char exec_reverse
[] = "reverse";
8832 static const char *exec_direction
= exec_forward
;
8833 static const char *const exec_direction_names
[] = {
8840 set_exec_direction_func (const char *args
, int from_tty
,
8841 struct cmd_list_element
*cmd
)
8843 if (target_can_execute_reverse
)
8845 if (!strcmp (exec_direction
, exec_forward
))
8846 execution_direction
= EXEC_FORWARD
;
8847 else if (!strcmp (exec_direction
, exec_reverse
))
8848 execution_direction
= EXEC_REVERSE
;
8852 exec_direction
= exec_forward
;
8853 error (_("Target does not support this operation."));
8858 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
8859 struct cmd_list_element
*cmd
, const char *value
)
8861 switch (execution_direction
) {
8863 fprintf_filtered (out
, _("Forward.\n"));
8866 fprintf_filtered (out
, _("Reverse.\n"));
8869 internal_error (__FILE__
, __LINE__
,
8870 _("bogus execution_direction value: %d"),
8871 (int) execution_direction
);
8876 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
8877 struct cmd_list_element
*c
, const char *value
)
8879 fprintf_filtered (file
, _("Resuming the execution of threads "
8880 "of all processes is %s.\n"), value
);
8883 /* Implementation of `siginfo' variable. */
8885 static const struct internalvar_funcs siginfo_funcs
=
8892 /* Callback for infrun's target events source. This is marked when a
8893 thread has a pending status to process. */
8896 infrun_async_inferior_event_handler (gdb_client_data data
)
8898 inferior_event_handler (INF_REG_EVENT
, NULL
);
8902 _initialize_infrun (void)
8904 struct cmd_list_element
*c
;
8906 /* Register extra event sources in the event loop. */
8907 infrun_async_inferior_event_token
8908 = create_async_event_handler (infrun_async_inferior_event_handler
, NULL
);
8910 add_info ("signals", info_signals_command
, _("\
8911 What debugger does when program gets various signals.\n\
8912 Specify a signal as argument to print info on that signal only."));
8913 add_info_alias ("handle", "signals", 0);
8915 c
= add_com ("handle", class_run
, handle_command
, _("\
8916 Specify how to handle signals.\n\
8917 Usage: handle SIGNAL [ACTIONS]\n\
8918 Args are signals and actions to apply to those signals.\n\
8919 If no actions are specified, the current settings for the specified signals\n\
8920 will be displayed instead.\n\
8922 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
8923 from 1-15 are allowed for compatibility with old versions of GDB.\n\
8924 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
8925 The special arg \"all\" is recognized to mean all signals except those\n\
8926 used by the debugger, typically SIGTRAP and SIGINT.\n\
8928 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
8929 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
8930 Stop means reenter debugger if this signal happens (implies print).\n\
8931 Print means print a message if this signal happens.\n\
8932 Pass means let program see this signal; otherwise program doesn't know.\n\
8933 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
8934 Pass and Stop may be combined.\n\
8936 Multiple signals may be specified. Signal numbers and signal names\n\
8937 may be interspersed with actions, with the actions being performed for\n\
8938 all signals cumulatively specified."));
8939 set_cmd_completer (c
, handle_completer
);
8942 stop_command
= add_cmd ("stop", class_obscure
,
8943 not_just_help_class_command
, _("\
8944 There is no `stop' command, but you can set a hook on `stop'.\n\
8945 This allows you to set a list of commands to be run each time execution\n\
8946 of the program stops."), &cmdlist
);
8948 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
8949 Set inferior debugging."), _("\
8950 Show inferior debugging."), _("\
8951 When non-zero, inferior specific debugging is enabled."),
8954 &setdebuglist
, &showdebuglist
);
8956 add_setshow_boolean_cmd ("displaced", class_maintenance
,
8957 &debug_displaced
, _("\
8958 Set displaced stepping debugging."), _("\
8959 Show displaced stepping debugging."), _("\
8960 When non-zero, displaced stepping specific debugging is enabled."),
8962 show_debug_displaced
,
8963 &setdebuglist
, &showdebuglist
);
8965 add_setshow_boolean_cmd ("non-stop", no_class
,
8967 Set whether gdb controls the inferior in non-stop mode."), _("\
8968 Show whether gdb controls the inferior in non-stop mode."), _("\
8969 When debugging a multi-threaded program and this setting is\n\
8970 off (the default, also called all-stop mode), when one thread stops\n\
8971 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
8972 all other threads in the program while you interact with the thread of\n\
8973 interest. When you continue or step a thread, you can allow the other\n\
8974 threads to run, or have them remain stopped, but while you inspect any\n\
8975 thread's state, all threads stop.\n\
8977 In non-stop mode, when one thread stops, other threads can continue\n\
8978 to run freely. You'll be able to step each thread independently,\n\
8979 leave it stopped or free to run as needed."),
8985 for (size_t i
= 0; i
< GDB_SIGNAL_LAST
; i
++)
8988 signal_print
[i
] = 1;
8989 signal_program
[i
] = 1;
8990 signal_catch
[i
] = 0;
8993 /* Signals caused by debugger's own actions should not be given to
8994 the program afterwards.
8996 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
8997 explicitly specifies that it should be delivered to the target
8998 program. Typically, that would occur when a user is debugging a
8999 target monitor on a simulator: the target monitor sets a
9000 breakpoint; the simulator encounters this breakpoint and halts
9001 the simulation handing control to GDB; GDB, noting that the stop
9002 address doesn't map to any known breakpoint, returns control back
9003 to the simulator; the simulator then delivers the hardware
9004 equivalent of a GDB_SIGNAL_TRAP to the program being
9006 signal_program
[GDB_SIGNAL_TRAP
] = 0;
9007 signal_program
[GDB_SIGNAL_INT
] = 0;
9009 /* Signals that are not errors should not normally enter the debugger. */
9010 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
9011 signal_print
[GDB_SIGNAL_ALRM
] = 0;
9012 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
9013 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
9014 signal_stop
[GDB_SIGNAL_PROF
] = 0;
9015 signal_print
[GDB_SIGNAL_PROF
] = 0;
9016 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
9017 signal_print
[GDB_SIGNAL_CHLD
] = 0;
9018 signal_stop
[GDB_SIGNAL_IO
] = 0;
9019 signal_print
[GDB_SIGNAL_IO
] = 0;
9020 signal_stop
[GDB_SIGNAL_POLL
] = 0;
9021 signal_print
[GDB_SIGNAL_POLL
] = 0;
9022 signal_stop
[GDB_SIGNAL_URG
] = 0;
9023 signal_print
[GDB_SIGNAL_URG
] = 0;
9024 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
9025 signal_print
[GDB_SIGNAL_WINCH
] = 0;
9026 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
9027 signal_print
[GDB_SIGNAL_PRIO
] = 0;
9029 /* These signals are used internally by user-level thread
9030 implementations. (See signal(5) on Solaris.) Like the above
9031 signals, a healthy program receives and handles them as part of
9032 its normal operation. */
9033 signal_stop
[GDB_SIGNAL_LWP
] = 0;
9034 signal_print
[GDB_SIGNAL_LWP
] = 0;
9035 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
9036 signal_print
[GDB_SIGNAL_WAITING
] = 0;
9037 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
9038 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
9039 signal_stop
[GDB_SIGNAL_LIBRT
] = 0;
9040 signal_print
[GDB_SIGNAL_LIBRT
] = 0;
9042 /* Update cached state. */
9043 signal_cache_update (-1);
9045 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
9046 &stop_on_solib_events
, _("\
9047 Set stopping for shared library events."), _("\
9048 Show stopping for shared library events."), _("\
9049 If nonzero, gdb will give control to the user when the dynamic linker\n\
9050 notifies gdb of shared library events. The most common event of interest\n\
9051 to the user would be loading/unloading of a new library."),
9052 set_stop_on_solib_events
,
9053 show_stop_on_solib_events
,
9054 &setlist
, &showlist
);
9056 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
9057 follow_fork_mode_kind_names
,
9058 &follow_fork_mode_string
, _("\
9059 Set debugger response to a program call of fork or vfork."), _("\
9060 Show debugger response to a program call of fork or vfork."), _("\
9061 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9062 parent - the original process is debugged after a fork\n\
9063 child - the new process is debugged after a fork\n\
9064 The unfollowed process will continue to run.\n\
9065 By default, the debugger will follow the parent process."),
9067 show_follow_fork_mode_string
,
9068 &setlist
, &showlist
);
9070 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
9071 follow_exec_mode_names
,
9072 &follow_exec_mode_string
, _("\
9073 Set debugger response to a program call of exec."), _("\
9074 Show debugger response to a program call of exec."), _("\
9075 An exec call replaces the program image of a process.\n\
9077 follow-exec-mode can be:\n\
9079 new - the debugger creates a new inferior and rebinds the process\n\
9080 to this new inferior. The program the process was running before\n\
9081 the exec call can be restarted afterwards by restarting the original\n\
9084 same - the debugger keeps the process bound to the same inferior.\n\
9085 The new executable image replaces the previous executable loaded in\n\
9086 the inferior. Restarting the inferior after the exec call restarts\n\
9087 the executable the process was running after the exec call.\n\
9089 By default, the debugger will use the same inferior."),
9091 show_follow_exec_mode_string
,
9092 &setlist
, &showlist
);
9094 add_setshow_enum_cmd ("scheduler-locking", class_run
,
9095 scheduler_enums
, &scheduler_mode
, _("\
9096 Set mode for locking scheduler during execution."), _("\
9097 Show mode for locking scheduler during execution."), _("\
9098 off == no locking (threads may preempt at any time)\n\
9099 on == full locking (no thread except the current thread may run)\n\
9100 This applies to both normal execution and replay mode.\n\
9101 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9102 In this mode, other threads may run during other commands.\n\
9103 This applies to both normal execution and replay mode.\n\
9104 replay == scheduler locked in replay mode and unlocked during normal execution."),
9105 set_schedlock_func
, /* traps on target vector */
9106 show_scheduler_mode
,
9107 &setlist
, &showlist
);
9109 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
9110 Set mode for resuming threads of all processes."), _("\
9111 Show mode for resuming threads of all processes."), _("\
9112 When on, execution commands (such as 'continue' or 'next') resume all\n\
9113 threads of all processes. When off (which is the default), execution\n\
9114 commands only resume the threads of the current process. The set of\n\
9115 threads that are resumed is further refined by the scheduler-locking\n\
9116 mode (see help set scheduler-locking)."),
9118 show_schedule_multiple
,
9119 &setlist
, &showlist
);
9121 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
9122 Set mode of the step operation."), _("\
9123 Show mode of the step operation."), _("\
9124 When set, doing a step over a function without debug line information\n\
9125 will stop at the first instruction of that function. Otherwise, the\n\
9126 function is skipped and the step command stops at a different source line."),
9128 show_step_stop_if_no_debug
,
9129 &setlist
, &showlist
);
9131 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
9132 &can_use_displaced_stepping
, _("\
9133 Set debugger's willingness to use displaced stepping."), _("\
9134 Show debugger's willingness to use displaced stepping."), _("\
9135 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9136 supported by the target architecture. If off, gdb will not use displaced\n\
9137 stepping to step over breakpoints, even if such is supported by the target\n\
9138 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9139 if the target architecture supports it and non-stop mode is active, but will not\n\
9140 use it in all-stop mode (see help set non-stop)."),
9142 show_can_use_displaced_stepping
,
9143 &setlist
, &showlist
);
9145 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
9146 &exec_direction
, _("Set direction of execution.\n\
9147 Options are 'forward' or 'reverse'."),
9148 _("Show direction of execution (forward/reverse)."),
9149 _("Tells gdb whether to execute forward or backward."),
9150 set_exec_direction_func
, show_exec_direction_func
,
9151 &setlist
, &showlist
);
9153 /* Set/show detach-on-fork: user-settable mode. */
9155 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
9156 Set whether gdb will detach the child of a fork."), _("\
9157 Show whether gdb will detach the child of a fork."), _("\
9158 Tells gdb whether to detach the child of a fork."),
9159 NULL
, NULL
, &setlist
, &showlist
);
9161 /* Set/show disable address space randomization mode. */
9163 add_setshow_boolean_cmd ("disable-randomization", class_support
,
9164 &disable_randomization
, _("\
9165 Set disabling of debuggee's virtual address space randomization."), _("\
9166 Show disabling of debuggee's virtual address space randomization."), _("\
9167 When this mode is on (which is the default), randomization of the virtual\n\
9168 address space is disabled. Standalone programs run with the randomization\n\
9169 enabled by default on some platforms."),
9170 &set_disable_randomization
,
9171 &show_disable_randomization
,
9172 &setlist
, &showlist
);
9174 /* ptid initializations */
9175 inferior_ptid
= null_ptid
;
9176 target_last_wait_ptid
= minus_one_ptid
;
9178 gdb::observers::thread_ptid_changed
.attach (infrun_thread_ptid_changed
);
9179 gdb::observers::thread_stop_requested
.attach (infrun_thread_stop_requested
);
9180 gdb::observers::thread_exit
.attach (infrun_thread_thread_exit
);
9181 gdb::observers::inferior_exit
.attach (infrun_inferior_exit
);
9183 /* Explicitly create without lookup, since that tries to create a
9184 value with a void typed value, and when we get here, gdbarch
9185 isn't initialized yet. At this point, we're quite sure there
9186 isn't another convenience variable of the same name. */
9187 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
9189 add_setshow_boolean_cmd ("observer", no_class
,
9190 &observer_mode_1
, _("\
9191 Set whether gdb controls the inferior in observer mode."), _("\
9192 Show whether gdb controls the inferior in observer mode."), _("\
9193 In observer mode, GDB can get data from the inferior, but not\n\
9194 affect its execution. Registers and memory may not be changed,\n\
9195 breakpoints may not be set, and the program cannot be interrupted\n\