1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986-2020 Free Software Foundation, Inc.
5 Copyright (C) 2019-2020 Advanced Micro Devices, Inc. All rights reserved.
7 This file is part of GDB.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>. */
28 #include "breakpoint.h"
32 #include "gdbthread.h"
39 #include "observable.h"
44 #include "mi/mi-common.h"
45 #include "event-top.h"
47 #include "record-full.h"
48 #include "inline-frame.h"
50 #include "tracepoint.h"
54 #include "completer.h"
55 #include "target-descriptions.h"
56 #include "target-dcache.h"
59 #include "event-loop.h"
60 #include "thread-fsm.h"
61 #include "gdbsupport/enum-flags.h"
62 #include "progspace-and-thread.h"
63 #include "gdbsupport/gdb_optional.h"
64 #include "arch-utils.h"
65 #include "gdbsupport/scope-exit.h"
66 #include "gdbsupport/forward-scope-exit.h"
68 /* Prototypes for local functions */
70 static void sig_print_info (enum gdb_signal
);
72 static void sig_print_header (void);
74 static int follow_fork (void);
76 static int follow_fork_inferior (int follow_child
, int detach_fork
);
78 static void follow_inferior_reset_breakpoints (void);
80 static int currently_stepping (struct thread_info
*tp
);
82 void nullify_last_target_wait_ptid (void);
84 static void insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*);
86 static void insert_step_resume_breakpoint_at_caller (struct frame_info
*);
88 static void insert_longjmp_resume_breakpoint (struct gdbarch
*, CORE_ADDR
);
90 static int maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
);
92 static void resume (gdb_signal sig
);
94 /* Asynchronous signal handler registered as event loop source for
95 when we have pending events ready to be passed to the core. */
96 static struct async_event_handler
*infrun_async_inferior_event_token
;
98 /* Stores whether infrun_async was previously enabled or disabled.
99 Starts off as -1, indicating "never enabled/disabled". */
100 static int infrun_is_async
= -1;
105 infrun_async (int enable
)
107 if (infrun_is_async
!= enable
)
109 infrun_is_async
= enable
;
112 fprintf_unfiltered (gdb_stdlog
,
113 "infrun: infrun_async(%d)\n",
117 mark_async_event_handler (infrun_async_inferior_event_token
);
119 clear_async_event_handler (infrun_async_inferior_event_token
);
126 mark_infrun_async_event_handler (void)
128 mark_async_event_handler (infrun_async_inferior_event_token
);
131 /* When set, stop the 'step' command if we enter a function which has
132 no line number information. The normal behavior is that we step
133 over such function. */
134 bool step_stop_if_no_debug
= false;
136 show_step_stop_if_no_debug (struct ui_file
*file
, int from_tty
,
137 struct cmd_list_element
*c
, const char *value
)
139 fprintf_filtered (file
, _("Mode of the step operation is %s.\n"), value
);
142 /* proceed and normal_stop use this to notify the user when the
143 inferior stopped in a different thread than it had been running
146 static ptid_t previous_inferior_ptid
;
148 /* If set (default for legacy reasons), when following a fork, GDB
149 will detach from one of the fork branches, child or parent.
150 Exactly which branch is detached depends on 'set follow-fork-mode'
153 static bool detach_fork
= true;
155 bool debug_displaced
= false;
157 show_debug_displaced (struct ui_file
*file
, int from_tty
,
158 struct cmd_list_element
*c
, const char *value
)
160 fprintf_filtered (file
, _("Displace stepping debugging is %s.\n"), value
);
163 unsigned int debug_infrun
= 0;
165 show_debug_infrun (struct ui_file
*file
, int from_tty
,
166 struct cmd_list_element
*c
, const char *value
)
168 fprintf_filtered (file
, _("Inferior debugging is %s.\n"), value
);
172 /* Support for disabling address space randomization. */
174 bool disable_randomization
= true;
177 show_disable_randomization (struct ui_file
*file
, int from_tty
,
178 struct cmd_list_element
*c
, const char *value
)
180 if (target_supports_disable_randomization ())
181 fprintf_filtered (file
,
182 _("Disabling randomization of debuggee's "
183 "virtual address space is %s.\n"),
186 fputs_filtered (_("Disabling randomization of debuggee's "
187 "virtual address space is unsupported on\n"
188 "this platform.\n"), file
);
192 set_disable_randomization (const char *args
, int from_tty
,
193 struct cmd_list_element
*c
)
195 if (!target_supports_disable_randomization ())
196 error (_("Disabling randomization of debuggee's "
197 "virtual address space is unsupported on\n"
201 /* User interface for non-stop mode. */
203 bool non_stop
= false;
204 static bool non_stop_1
= false;
207 set_non_stop (const char *args
, int from_tty
,
208 struct cmd_list_element
*c
)
210 if (target_has_execution
)
212 non_stop_1
= non_stop
;
213 error (_("Cannot change this setting while the inferior is running."));
216 non_stop
= non_stop_1
;
220 show_non_stop (struct ui_file
*file
, int from_tty
,
221 struct cmd_list_element
*c
, const char *value
)
223 fprintf_filtered (file
,
224 _("Controlling the inferior in non-stop mode is %s.\n"),
228 /* "Observer mode" is somewhat like a more extreme version of
229 non-stop, in which all GDB operations that might affect the
230 target's execution have been disabled. */
232 bool observer_mode
= false;
233 static bool observer_mode_1
= false;
236 set_observer_mode (const char *args
, int from_tty
,
237 struct cmd_list_element
*c
)
239 if (target_has_execution
)
241 observer_mode_1
= observer_mode
;
242 error (_("Cannot change this setting while the inferior is running."));
245 observer_mode
= observer_mode_1
;
247 may_write_registers
= !observer_mode
;
248 may_write_memory
= !observer_mode
;
249 may_insert_breakpoints
= !observer_mode
;
250 may_insert_tracepoints
= !observer_mode
;
251 /* We can insert fast tracepoints in or out of observer mode,
252 but enable them if we're going into this mode. */
254 may_insert_fast_tracepoints
= true;
255 may_stop
= !observer_mode
;
256 update_target_permissions ();
258 /* Going *into* observer mode we must force non-stop, then
259 going out we leave it that way. */
262 pagination_enabled
= 0;
263 non_stop
= non_stop_1
= true;
267 printf_filtered (_("Observer mode is now %s.\n"),
268 (observer_mode
? "on" : "off"));
272 show_observer_mode (struct ui_file
*file
, int from_tty
,
273 struct cmd_list_element
*c
, const char *value
)
275 fprintf_filtered (file
, _("Observer mode is %s.\n"), value
);
278 /* This updates the value of observer mode based on changes in
279 permissions. Note that we are deliberately ignoring the values of
280 may-write-registers and may-write-memory, since the user may have
281 reason to enable these during a session, for instance to turn on a
282 debugging-related global. */
285 update_observer_mode (void)
287 bool newval
= (!may_insert_breakpoints
288 && !may_insert_tracepoints
289 && may_insert_fast_tracepoints
293 /* Let the user know if things change. */
294 if (newval
!= observer_mode
)
295 printf_filtered (_("Observer mode is now %s.\n"),
296 (newval
? "on" : "off"));
298 observer_mode
= observer_mode_1
= newval
;
301 /* Tables of how to react to signals; the user sets them. */
303 static unsigned char signal_stop
[GDB_SIGNAL_LAST
];
304 static unsigned char signal_print
[GDB_SIGNAL_LAST
];
305 static unsigned char signal_program
[GDB_SIGNAL_LAST
];
307 /* Table of signals that are registered with "catch signal". A
308 non-zero entry indicates that the signal is caught by some "catch
310 static unsigned char signal_catch
[GDB_SIGNAL_LAST
];
312 /* Table of signals that the target may silently handle.
313 This is automatically determined from the flags above,
314 and simply cached here. */
315 static unsigned char signal_pass
[GDB_SIGNAL_LAST
];
317 #define SET_SIGS(nsigs,sigs,flags) \
319 int signum = (nsigs); \
320 while (signum-- > 0) \
321 if ((sigs)[signum]) \
322 (flags)[signum] = 1; \
325 #define UNSET_SIGS(nsigs,sigs,flags) \
327 int signum = (nsigs); \
328 while (signum-- > 0) \
329 if ((sigs)[signum]) \
330 (flags)[signum] = 0; \
333 /* Update the target's copy of SIGNAL_PROGRAM. The sole purpose of
334 this function is to avoid exporting `signal_program'. */
337 update_signals_program_target (void)
339 target_program_signals (signal_program
);
342 /* Value to pass to target_resume() to cause all threads to resume. */
344 #define RESUME_ALL minus_one_ptid
346 /* Command list pointer for the "stop" placeholder. */
348 static struct cmd_list_element
*stop_command
;
350 /* Nonzero if we want to give control to the user when we're notified
351 of shared library events by the dynamic linker. */
352 int stop_on_solib_events
;
354 /* Enable or disable optional shared library event breakpoints
355 as appropriate when the above flag is changed. */
358 set_stop_on_solib_events (const char *args
,
359 int from_tty
, struct cmd_list_element
*c
)
361 update_solib_breakpoints ();
365 show_stop_on_solib_events (struct ui_file
*file
, int from_tty
,
366 struct cmd_list_element
*c
, const char *value
)
368 fprintf_filtered (file
, _("Stopping for shared library events is %s.\n"),
372 /* Nonzero after stop if current stack frame should be printed. */
374 static int stop_print_frame
;
376 /* This is a cached copy of the pid/waitstatus of the last event
377 returned by target_wait()/deprecated_target_wait_hook(). This
378 information is returned by get_last_target_status(). */
379 static ptid_t target_last_wait_ptid
;
380 static struct target_waitstatus target_last_waitstatus
;
382 void init_thread_stepping_state (struct thread_info
*tss
);
384 static const char follow_fork_mode_child
[] = "child";
385 static const char follow_fork_mode_parent
[] = "parent";
387 static const char *const follow_fork_mode_kind_names
[] = {
388 follow_fork_mode_child
,
389 follow_fork_mode_parent
,
393 static const char *follow_fork_mode_string
= follow_fork_mode_parent
;
395 show_follow_fork_mode_string (struct ui_file
*file
, int from_tty
,
396 struct cmd_list_element
*c
, const char *value
)
398 fprintf_filtered (file
,
399 _("Debugger response to a program "
400 "call of fork or vfork is \"%s\".\n"),
405 /* Handle changes to the inferior list based on the type of fork,
406 which process is being followed, and whether the other process
407 should be detached. On entry inferior_ptid must be the ptid of
408 the fork parent. At return inferior_ptid is the ptid of the
409 followed inferior. */
412 follow_fork_inferior (int follow_child
, int detach_fork
)
415 ptid_t parent_ptid
, child_ptid
;
417 has_vforked
= (inferior_thread ()->pending_follow
.kind
418 == TARGET_WAITKIND_VFORKED
);
419 parent_ptid
= inferior_ptid
;
420 child_ptid
= inferior_thread ()->pending_follow
.value
.related_pid
;
423 && !non_stop
/* Non-stop always resumes both branches. */
424 && current_ui
->prompt_state
== PROMPT_BLOCKED
425 && !(follow_child
|| detach_fork
|| sched_multi
))
427 /* The parent stays blocked inside the vfork syscall until the
428 child execs or exits. If we don't let the child run, then
429 the parent stays blocked. If we're telling the parent to run
430 in the foreground, the user will not be able to ctrl-c to get
431 back the terminal, effectively hanging the debug session. */
432 fprintf_filtered (gdb_stderr
, _("\
433 Can not resume the parent process over vfork in the foreground while\n\
434 holding the child stopped. Try \"set detach-on-fork\" or \
435 \"set schedule-multiple\".\n"));
441 /* Detach new forked process? */
444 /* Before detaching from the child, remove all breakpoints
445 from it. If we forked, then this has already been taken
446 care of by infrun.c. If we vforked however, any
447 breakpoint inserted in the parent is visible in the
448 child, even those added while stopped in a vfork
449 catchpoint. This will remove the breakpoints from the
450 parent also, but they'll be reinserted below. */
453 /* Keep breakpoints list in sync. */
454 remove_breakpoints_inf (current_inferior ());
457 if (print_inferior_events
)
459 /* Ensure that we have a process ptid. */
460 ptid_t process_ptid
= ptid_t (child_ptid
.pid ());
462 target_terminal::ours_for_output ();
463 fprintf_filtered (gdb_stdlog
,
464 _("[Detaching after %s from child %s]\n"),
465 has_vforked
? "vfork" : "fork",
466 target_pid_to_str (process_ptid
).c_str ());
471 struct inferior
*parent_inf
, *child_inf
;
473 /* Add process to GDB's tables. */
474 child_inf
= add_inferior (child_ptid
.pid ());
476 parent_inf
= current_inferior ();
477 child_inf
->attach_flag
= parent_inf
->attach_flag
;
478 copy_terminal_info (child_inf
, parent_inf
);
479 child_inf
->gdbarch
= parent_inf
->gdbarch
;
480 copy_inferior_target_desc_info (child_inf
, parent_inf
);
482 scoped_restore_current_pspace_and_thread restore_pspace_thread
;
484 inferior_ptid
= child_ptid
;
485 add_thread_silent (inferior_ptid
);
486 set_current_inferior (child_inf
);
487 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
489 /* If this is a vfork child, then the address-space is
490 shared with the parent. */
493 child_inf
->pspace
= parent_inf
->pspace
;
494 child_inf
->aspace
= parent_inf
->aspace
;
496 /* The parent will be frozen until the child is done
497 with the shared region. Keep track of the
499 child_inf
->vfork_parent
= parent_inf
;
500 child_inf
->pending_detach
= 0;
501 parent_inf
->vfork_child
= child_inf
;
502 parent_inf
->pending_detach
= 0;
506 child_inf
->aspace
= new_address_space ();
507 child_inf
->pspace
= new program_space (child_inf
->aspace
);
508 child_inf
->removable
= 1;
509 set_current_program_space (child_inf
->pspace
);
510 clone_program_space (child_inf
->pspace
, parent_inf
->pspace
);
512 /* Let the shared library layer (e.g., solib-svr4) learn
513 about this new process, relocate the cloned exec, pull
514 in shared libraries, and install the solib event
515 breakpoint. If a "cloned-VM" event was propagated
516 better throughout the core, this wouldn't be
518 solib_create_inferior_hook (0);
524 struct inferior
*parent_inf
;
526 parent_inf
= current_inferior ();
528 /* If we detached from the child, then we have to be careful
529 to not insert breakpoints in the parent until the child
530 is done with the shared memory region. However, if we're
531 staying attached to the child, then we can and should
532 insert breakpoints, so that we can debug it. A
533 subsequent child exec or exit is enough to know when does
534 the child stops using the parent's address space. */
535 parent_inf
->waiting_for_vfork_done
= detach_fork
;
536 parent_inf
->pspace
->breakpoints_not_allowed
= detach_fork
;
541 /* Follow the child. */
542 struct inferior
*parent_inf
, *child_inf
;
543 struct program_space
*parent_pspace
;
545 if (print_inferior_events
)
547 std::string parent_pid
= target_pid_to_str (parent_ptid
);
548 std::string child_pid
= target_pid_to_str (child_ptid
);
550 target_terminal::ours_for_output ();
551 fprintf_filtered (gdb_stdlog
,
552 _("[Attaching after %s %s to child %s]\n"),
554 has_vforked
? "vfork" : "fork",
558 /* Add the new inferior first, so that the target_detach below
559 doesn't unpush the target. */
561 child_inf
= add_inferior (child_ptid
.pid ());
563 parent_inf
= current_inferior ();
564 child_inf
->attach_flag
= parent_inf
->attach_flag
;
565 copy_terminal_info (child_inf
, parent_inf
);
566 child_inf
->gdbarch
= parent_inf
->gdbarch
;
567 copy_inferior_target_desc_info (child_inf
, parent_inf
);
569 parent_pspace
= parent_inf
->pspace
;
571 /* If we're vforking, we want to hold on to the parent until the
572 child exits or execs. At child exec or exit time we can
573 remove the old breakpoints from the parent and detach or
574 resume debugging it. Otherwise, detach the parent now; we'll
575 want to reuse it's program/address spaces, but we can't set
576 them to the child before removing breakpoints from the
577 parent, otherwise, the breakpoints module could decide to
578 remove breakpoints from the wrong process (since they'd be
579 assigned to the same address space). */
583 gdb_assert (child_inf
->vfork_parent
== NULL
);
584 gdb_assert (parent_inf
->vfork_child
== NULL
);
585 child_inf
->vfork_parent
= parent_inf
;
586 child_inf
->pending_detach
= 0;
587 parent_inf
->vfork_child
= child_inf
;
588 parent_inf
->pending_detach
= detach_fork
;
589 parent_inf
->waiting_for_vfork_done
= 0;
591 else if (detach_fork
)
593 if (print_inferior_events
)
595 /* Ensure that we have a process ptid. */
596 ptid_t process_ptid
= ptid_t (parent_ptid
.pid ());
598 target_terminal::ours_for_output ();
599 fprintf_filtered (gdb_stdlog
,
600 _("[Detaching after fork from "
602 target_pid_to_str (process_ptid
).c_str ());
605 target_detach (parent_inf
, 0);
608 /* Note that the detach above makes PARENT_INF dangling. */
610 /* Add the child thread to the appropriate lists, and switch to
611 this new thread, before cloning the program space, and
612 informing the solib layer about this new process. */
614 inferior_ptid
= child_ptid
;
615 add_thread_silent (inferior_ptid
);
616 set_current_inferior (child_inf
);
618 /* If this is a vfork child, then the address-space is shared
619 with the parent. If we detached from the parent, then we can
620 reuse the parent's program/address spaces. */
621 if (has_vforked
|| detach_fork
)
623 child_inf
->pspace
= parent_pspace
;
624 child_inf
->aspace
= child_inf
->pspace
->aspace
;
628 child_inf
->aspace
= new_address_space ();
629 child_inf
->pspace
= new program_space (child_inf
->aspace
);
630 child_inf
->removable
= 1;
631 child_inf
->symfile_flags
= SYMFILE_NO_READ
;
632 set_current_program_space (child_inf
->pspace
);
633 clone_program_space (child_inf
->pspace
, parent_pspace
);
635 /* Let the shared library layer (e.g., solib-svr4) learn
636 about this new process, relocate the cloned exec, pull in
637 shared libraries, and install the solib event breakpoint.
638 If a "cloned-VM" event was propagated better throughout
639 the core, this wouldn't be required. */
640 solib_create_inferior_hook (0);
644 return target_follow_fork (follow_child
, detach_fork
);
647 /* Tell the target to follow the fork we're stopped at. Returns true
648 if the inferior should be resumed; false, if the target for some
649 reason decided it's best not to resume. */
654 int follow_child
= (follow_fork_mode_string
== follow_fork_mode_child
);
655 int should_resume
= 1;
656 struct thread_info
*tp
;
658 /* Copy user stepping state to the new inferior thread. FIXME: the
659 followed fork child thread should have a copy of most of the
660 parent thread structure's run control related fields, not just these.
661 Initialized to avoid "may be used uninitialized" warnings from gcc. */
662 struct breakpoint
*step_resume_breakpoint
= NULL
;
663 struct breakpoint
*exception_resume_breakpoint
= NULL
;
664 CORE_ADDR step_range_start
= 0;
665 CORE_ADDR step_range_end
= 0;
666 struct frame_id step_frame_id
= { 0 };
667 struct thread_fsm
*thread_fsm
= NULL
;
672 struct target_waitstatus wait_status
;
674 /* Get the last target status returned by target_wait(). */
675 get_last_target_status (&wait_ptid
, &wait_status
);
677 /* If not stopped at a fork event, then there's nothing else to
679 if (wait_status
.kind
!= TARGET_WAITKIND_FORKED
680 && wait_status
.kind
!= TARGET_WAITKIND_VFORKED
)
683 /* Check if we switched over from WAIT_PTID, since the event was
685 if (wait_ptid
!= minus_one_ptid
686 && inferior_ptid
!= wait_ptid
)
688 /* We did. Switch back to WAIT_PTID thread, to tell the
689 target to follow it (in either direction). We'll
690 afterwards refuse to resume, and inform the user what
692 thread_info
*wait_thread
693 = find_thread_ptid (wait_ptid
);
694 switch_to_thread (wait_thread
);
699 tp
= inferior_thread ();
701 /* If there were any forks/vforks that were caught and are now to be
702 followed, then do so now. */
703 switch (tp
->pending_follow
.kind
)
705 case TARGET_WAITKIND_FORKED
:
706 case TARGET_WAITKIND_VFORKED
:
708 ptid_t parent
, child
;
710 /* If the user did a next/step, etc, over a fork call,
711 preserve the stepping state in the fork child. */
712 if (follow_child
&& should_resume
)
714 step_resume_breakpoint
= clone_momentary_breakpoint
715 (tp
->control
.step_resume_breakpoint
);
716 step_range_start
= tp
->control
.step_range_start
;
717 step_range_end
= tp
->control
.step_range_end
;
718 step_frame_id
= tp
->control
.step_frame_id
;
719 exception_resume_breakpoint
720 = clone_momentary_breakpoint (tp
->control
.exception_resume_breakpoint
);
721 thread_fsm
= tp
->thread_fsm
;
723 /* For now, delete the parent's sr breakpoint, otherwise,
724 parent/child sr breakpoints are considered duplicates,
725 and the child version will not be installed. Remove
726 this when the breakpoints module becomes aware of
727 inferiors and address spaces. */
728 delete_step_resume_breakpoint (tp
);
729 tp
->control
.step_range_start
= 0;
730 tp
->control
.step_range_end
= 0;
731 tp
->control
.step_frame_id
= null_frame_id
;
732 delete_exception_resume_breakpoint (tp
);
733 tp
->thread_fsm
= NULL
;
736 parent
= inferior_ptid
;
737 child
= tp
->pending_follow
.value
.related_pid
;
739 /* Set up inferior(s) as specified by the caller, and tell the
740 target to do whatever is necessary to follow either parent
742 if (follow_fork_inferior (follow_child
, detach_fork
))
744 /* Target refused to follow, or there's some other reason
745 we shouldn't resume. */
750 /* This pending follow fork event is now handled, one way
751 or another. The previous selected thread may be gone
752 from the lists by now, but if it is still around, need
753 to clear the pending follow request. */
754 tp
= find_thread_ptid (parent
);
756 tp
->pending_follow
.kind
= TARGET_WAITKIND_SPURIOUS
;
758 /* This makes sure we don't try to apply the "Switched
759 over from WAIT_PID" logic above. */
760 nullify_last_target_wait_ptid ();
762 /* If we followed the child, switch to it... */
765 thread_info
*child_thr
= find_thread_ptid (child
);
766 switch_to_thread (child_thr
);
768 /* ... and preserve the stepping state, in case the
769 user was stepping over the fork call. */
772 tp
= inferior_thread ();
773 tp
->control
.step_resume_breakpoint
774 = step_resume_breakpoint
;
775 tp
->control
.step_range_start
= step_range_start
;
776 tp
->control
.step_range_end
= step_range_end
;
777 tp
->control
.step_frame_id
= step_frame_id
;
778 tp
->control
.exception_resume_breakpoint
779 = exception_resume_breakpoint
;
780 tp
->thread_fsm
= thread_fsm
;
784 /* If we get here, it was because we're trying to
785 resume from a fork catchpoint, but, the user
786 has switched threads away from the thread that
787 forked. In that case, the resume command
788 issued is most likely not applicable to the
789 child, so just warn, and refuse to resume. */
790 warning (_("Not resuming: switched threads "
791 "before following fork child."));
794 /* Reset breakpoints in the child as appropriate. */
795 follow_inferior_reset_breakpoints ();
800 case TARGET_WAITKIND_SPURIOUS
:
801 /* Nothing to follow. */
804 internal_error (__FILE__
, __LINE__
,
805 "Unexpected pending_follow.kind %d\n",
806 tp
->pending_follow
.kind
);
810 return should_resume
;
814 follow_inferior_reset_breakpoints (void)
816 struct thread_info
*tp
= inferior_thread ();
818 /* Was there a step_resume breakpoint? (There was if the user
819 did a "next" at the fork() call.) If so, explicitly reset its
820 thread number. Cloned step_resume breakpoints are disabled on
821 creation, so enable it here now that it is associated with the
824 step_resumes are a form of bp that are made to be per-thread.
825 Since we created the step_resume bp when the parent process
826 was being debugged, and now are switching to the child process,
827 from the breakpoint package's viewpoint, that's a switch of
828 "threads". We must update the bp's notion of which thread
829 it is for, or it'll be ignored when it triggers. */
831 if (tp
->control
.step_resume_breakpoint
)
833 breakpoint_re_set_thread (tp
->control
.step_resume_breakpoint
);
834 tp
->control
.step_resume_breakpoint
->loc
->enabled
= 1;
837 /* Treat exception_resume breakpoints like step_resume breakpoints. */
838 if (tp
->control
.exception_resume_breakpoint
)
840 breakpoint_re_set_thread (tp
->control
.exception_resume_breakpoint
);
841 tp
->control
.exception_resume_breakpoint
->loc
->enabled
= 1;
844 /* Reinsert all breakpoints in the child. The user may have set
845 breakpoints after catching the fork, in which case those
846 were never set in the child, but only in the parent. This makes
847 sure the inserted breakpoints match the breakpoint list. */
849 breakpoint_re_set ();
850 insert_breakpoints ();
853 /* The child has exited or execed: resume threads of the parent the
854 user wanted to be executing. */
857 proceed_after_vfork_done (struct thread_info
*thread
,
860 int pid
= * (int *) arg
;
862 if (thread
->ptid
.pid () == pid
863 && thread
->state
== THREAD_RUNNING
864 && !thread
->executing
865 && !thread
->stop_requested
866 && thread
->suspend
.stop_signal
== GDB_SIGNAL_0
)
869 fprintf_unfiltered (gdb_stdlog
,
870 "infrun: resuming vfork parent thread %s\n",
871 target_pid_to_str (thread
->ptid
).c_str ());
873 switch_to_thread (thread
);
874 clear_proceed_status (0);
875 proceed ((CORE_ADDR
) -1, GDB_SIGNAL_DEFAULT
);
881 /* Save/restore inferior_ptid, current program space and current
882 inferior. Only use this if the current context points at an exited
883 inferior (and therefore there's no current thread to save). */
884 class scoped_restore_exited_inferior
887 scoped_restore_exited_inferior ()
888 : m_saved_ptid (&inferior_ptid
)
892 scoped_restore_tmpl
<ptid_t
> m_saved_ptid
;
893 scoped_restore_current_program_space m_pspace
;
894 scoped_restore_current_inferior m_inferior
;
897 /* Called whenever we notice an exec or exit event, to handle
898 detaching or resuming a vfork parent. */
901 handle_vfork_child_exec_or_exit (int exec
)
903 struct inferior
*inf
= current_inferior ();
905 if (inf
->vfork_parent
)
907 int resume_parent
= -1;
909 /* This exec or exit marks the end of the shared memory region
910 between the parent and the child. Break the bonds. */
911 inferior
*vfork_parent
= inf
->vfork_parent
;
912 inf
->vfork_parent
->vfork_child
= NULL
;
913 inf
->vfork_parent
= NULL
;
915 /* If the user wanted to detach from the parent, now is the
917 if (vfork_parent
->pending_detach
)
919 struct thread_info
*tp
;
920 struct program_space
*pspace
;
921 struct address_space
*aspace
;
923 /* follow-fork child, detach-on-fork on. */
925 vfork_parent
->pending_detach
= 0;
927 gdb::optional
<scoped_restore_exited_inferior
>
928 maybe_restore_inferior
;
929 gdb::optional
<scoped_restore_current_pspace_and_thread
>
930 maybe_restore_thread
;
932 /* If we're handling a child exit, then inferior_ptid points
933 at the inferior's pid, not to a thread. */
935 maybe_restore_inferior
.emplace ();
937 maybe_restore_thread
.emplace ();
939 /* We're letting loose of the parent. */
940 tp
= any_live_thread_of_inferior (vfork_parent
);
941 switch_to_thread (tp
);
943 /* We're about to detach from the parent, which implicitly
944 removes breakpoints from its address space. There's a
945 catch here: we want to reuse the spaces for the child,
946 but, parent/child are still sharing the pspace at this
947 point, although the exec in reality makes the kernel give
948 the child a fresh set of new pages. The problem here is
949 that the breakpoints module being unaware of this, would
950 likely chose the child process to write to the parent
951 address space. Swapping the child temporarily away from
952 the spaces has the desired effect. Yes, this is "sort
955 pspace
= inf
->pspace
;
956 aspace
= inf
->aspace
;
960 if (print_inferior_events
)
963 = target_pid_to_str (ptid_t (vfork_parent
->pid
));
965 target_terminal::ours_for_output ();
969 fprintf_filtered (gdb_stdlog
,
970 _("[Detaching vfork parent %s "
971 "after child exec]\n"), pidstr
.c_str ());
975 fprintf_filtered (gdb_stdlog
,
976 _("[Detaching vfork parent %s "
977 "after child exit]\n"), pidstr
.c_str ());
981 target_detach (vfork_parent
, 0);
984 inf
->pspace
= pspace
;
985 inf
->aspace
= aspace
;
989 /* We're staying attached to the parent, so, really give the
990 child a new address space. */
991 inf
->pspace
= new program_space (maybe_new_address_space ());
992 inf
->aspace
= inf
->pspace
->aspace
;
994 set_current_program_space (inf
->pspace
);
996 resume_parent
= vfork_parent
->pid
;
1000 struct program_space
*pspace
;
1002 /* If this is a vfork child exiting, then the pspace and
1003 aspaces were shared with the parent. Since we're
1004 reporting the process exit, we'll be mourning all that is
1005 found in the address space, and switching to null_ptid,
1006 preparing to start a new inferior. But, since we don't
1007 want to clobber the parent's address/program spaces, we
1008 go ahead and create a new one for this exiting
1011 /* Switch to null_ptid while running clone_program_space, so
1012 that clone_program_space doesn't want to read the
1013 selected frame of a dead process. */
1014 scoped_restore restore_ptid
1015 = make_scoped_restore (&inferior_ptid
, null_ptid
);
1017 /* This inferior is dead, so avoid giving the breakpoints
1018 module the option to write through to it (cloning a
1019 program space resets breakpoints). */
1022 pspace
= new program_space (maybe_new_address_space ());
1023 set_current_program_space (pspace
);
1025 inf
->symfile_flags
= SYMFILE_NO_READ
;
1026 clone_program_space (pspace
, vfork_parent
->pspace
);
1027 inf
->pspace
= pspace
;
1028 inf
->aspace
= pspace
->aspace
;
1030 resume_parent
= vfork_parent
->pid
;
1033 gdb_assert (current_program_space
== inf
->pspace
);
1035 if (non_stop
&& resume_parent
!= -1)
1037 /* If the user wanted the parent to be running, let it go
1039 scoped_restore_current_thread restore_thread
;
1042 fprintf_unfiltered (gdb_stdlog
,
1043 "infrun: resuming vfork parent process %d\n",
1046 iterate_over_threads (proceed_after_vfork_done
, &resume_parent
);
1051 /* Enum strings for "set|show follow-exec-mode". */
1053 static const char follow_exec_mode_new
[] = "new";
1054 static const char follow_exec_mode_same
[] = "same";
1055 static const char *const follow_exec_mode_names
[] =
1057 follow_exec_mode_new
,
1058 follow_exec_mode_same
,
1062 static const char *follow_exec_mode_string
= follow_exec_mode_same
;
1064 show_follow_exec_mode_string (struct ui_file
*file
, int from_tty
,
1065 struct cmd_list_element
*c
, const char *value
)
1067 fprintf_filtered (file
, _("Follow exec mode is \"%s\".\n"), value
);
1070 /* EXEC_FILE_TARGET is assumed to be non-NULL. */
1073 follow_exec (ptid_t ptid
, const char *exec_file_target
)
1075 struct inferior
*inf
= current_inferior ();
1076 int pid
= ptid
.pid ();
1077 ptid_t process_ptid
;
1079 /* Switch terminal for any messages produced e.g. by
1080 breakpoint_re_set. */
1081 target_terminal::ours_for_output ();
1083 /* This is an exec event that we actually wish to pay attention to.
1084 Refresh our symbol table to the newly exec'd program, remove any
1085 momentary bp's, etc.
1087 If there are breakpoints, they aren't really inserted now,
1088 since the exec() transformed our inferior into a fresh set
1091 We want to preserve symbolic breakpoints on the list, since
1092 we have hopes that they can be reset after the new a.out's
1093 symbol table is read.
1095 However, any "raw" breakpoints must be removed from the list
1096 (e.g., the solib bp's), since their address is probably invalid
1099 And, we DON'T want to call delete_breakpoints() here, since
1100 that may write the bp's "shadow contents" (the instruction
1101 value that was overwritten with a TRAP instruction). Since
1102 we now have a new a.out, those shadow contents aren't valid. */
1104 mark_breakpoints_out ();
1106 /* The target reports the exec event to the main thread, even if
1107 some other thread does the exec, and even if the main thread was
1108 stopped or already gone. We may still have non-leader threads of
1109 the process on our list. E.g., on targets that don't have thread
1110 exit events (like remote); or on native Linux in non-stop mode if
1111 there were only two threads in the inferior and the non-leader
1112 one is the one that execs (and nothing forces an update of the
1113 thread list up to here). When debugging remotely, it's best to
1114 avoid extra traffic, when possible, so avoid syncing the thread
1115 list with the target, and instead go ahead and delete all threads
1116 of the process but one that reported the event. Note this must
1117 be done before calling update_breakpoints_after_exec, as
1118 otherwise clearing the threads' resources would reference stale
1119 thread breakpoints -- it may have been one of these threads that
1120 stepped across the exec. We could just clear their stepping
1121 states, but as long as we're iterating, might as well delete
1122 them. Deleting them now rather than at the next user-visible
1123 stop provides a nicer sequence of events for user and MI
1125 for (thread_info
*th
: all_threads_safe ())
1126 if (th
->ptid
.pid () == pid
&& th
->ptid
!= ptid
)
1129 /* We also need to clear any left over stale state for the
1130 leader/event thread. E.g., if there was any step-resume
1131 breakpoint or similar, it's gone now. We cannot truly
1132 step-to-next statement through an exec(). */
1133 thread_info
*th
= inferior_thread ();
1134 th
->control
.step_resume_breakpoint
= NULL
;
1135 th
->control
.exception_resume_breakpoint
= NULL
;
1136 th
->control
.single_step_breakpoints
= NULL
;
1137 th
->control
.step_range_start
= 0;
1138 th
->control
.step_range_end
= 0;
1140 /* The user may have had the main thread held stopped in the
1141 previous image (e.g., schedlock on, or non-stop). Release
1143 th
->stop_requested
= 0;
1145 update_breakpoints_after_exec ();
1147 /* What is this a.out's name? */
1148 process_ptid
= ptid_t (pid
);
1149 printf_unfiltered (_("%s is executing new program: %s\n"),
1150 target_pid_to_str (process_ptid
).c_str (),
1153 /* We've followed the inferior through an exec. Therefore, the
1154 inferior has essentially been killed & reborn. */
1156 breakpoint_init_inferior (inf_execd
);
1158 gdb::unique_xmalloc_ptr
<char> exec_file_host
1159 = exec_file_find (exec_file_target
, NULL
);
1161 /* If we were unable to map the executable target pathname onto a host
1162 pathname, tell the user that. Otherwise GDB's subsequent behavior
1163 is confusing. Maybe it would even be better to stop at this point
1164 so that the user can specify a file manually before continuing. */
1165 if (exec_file_host
== NULL
)
1166 warning (_("Could not load symbols for executable %s.\n"
1167 "Do you need \"set sysroot\"?"),
1170 /* Reset the shared library package. This ensures that we get a
1171 shlib event when the child reaches "_start", at which point the
1172 dld will have had a chance to initialize the child. */
1173 /* Also, loading a symbol file below may trigger symbol lookups, and
1174 we don't want those to be satisfied by the libraries of the
1175 previous incarnation of this process. */
1176 no_shared_libraries (NULL
, 0);
1178 if (follow_exec_mode_string
== follow_exec_mode_new
)
1180 /* The user wants to keep the old inferior and program spaces
1181 around. Create a new fresh one, and switch to it. */
1183 /* Do exit processing for the original inferior before setting the new
1184 inferior's pid. Having two inferiors with the same pid would confuse
1185 find_inferior_p(t)id. Transfer the terminal state and info from the
1186 old to the new inferior. */
1187 inf
= add_inferior_with_spaces ();
1188 swap_terminal_info (inf
, current_inferior ());
1189 exit_inferior_silent (current_inferior ());
1192 target_follow_exec (inf
, exec_file_target
);
1194 set_current_inferior (inf
);
1195 set_current_program_space (inf
->pspace
);
1200 /* The old description may no longer be fit for the new image.
1201 E.g, a 64-bit process exec'ed a 32-bit process. Clear the
1202 old description; we'll read a new one below. No need to do
1203 this on "follow-exec-mode new", as the old inferior stays
1204 around (its description is later cleared/refetched on
1206 target_clear_description ();
1209 gdb_assert (current_program_space
== inf
->pspace
);
1211 /* Attempt to open the exec file. SYMFILE_DEFER_BP_RESET is used
1212 because the proper displacement for a PIE (Position Independent
1213 Executable) main symbol file will only be computed by
1214 solib_create_inferior_hook below. breakpoint_re_set would fail
1215 to insert the breakpoints with the zero displacement. */
1216 try_open_exec_file (exec_file_host
.get (), inf
, SYMFILE_DEFER_BP_RESET
);
1218 /* If the target can specify a description, read it. Must do this
1219 after flipping to the new executable (because the target supplied
1220 description must be compatible with the executable's
1221 architecture, and the old executable may e.g., be 32-bit, while
1222 the new one 64-bit), and before anything involving memory or
1224 target_find_description ();
1226 solib_create_inferior_hook (0);
1228 jit_inferior_created_hook ();
1230 breakpoint_re_set ();
1232 /* Reinsert all breakpoints. (Those which were symbolic have
1233 been reset to the proper address in the new a.out, thanks
1234 to symbol_file_command...). */
1235 insert_breakpoints ();
1237 /* The next resume of this inferior should bring it to the shlib
1238 startup breakpoints. (If the user had also set bp's on
1239 "main" from the old (parent) process, then they'll auto-
1240 matically get reset there in the new process.). */
1243 /* The queue of threads that need to do a step-over operation to get
1244 past e.g., a breakpoint. What technique is used to step over the
1245 breakpoint/watchpoint does not matter -- all threads end up in the
1246 same queue, to maintain rough temporal order of execution, in order
1247 to avoid starvation, otherwise, we could e.g., find ourselves
1248 constantly stepping the same couple threads past their breakpoints
1249 over and over, if the single-step finish fast enough. */
1250 struct thread_info
*step_over_queue_head
;
1252 /* Bit flags indicating what the thread needs to step over. */
1254 enum step_over_what_flag
1256 /* Step over a breakpoint. */
1257 STEP_OVER_BREAKPOINT
= 1,
1259 /* Step past a non-continuable watchpoint, in order to let the
1260 instruction execute so we can evaluate the watchpoint
1262 STEP_OVER_WATCHPOINT
= 2
1264 DEF_ENUM_FLAGS_TYPE (enum step_over_what_flag
, step_over_what
);
1266 /* Info about an instruction that is being stepped over. */
1268 struct step_over_info
1270 /* If we're stepping past a breakpoint, this is the address space
1271 and address of the instruction the breakpoint is set at. We'll
1272 skip inserting all breakpoints here. Valid iff ASPACE is
1274 const address_space
*aspace
;
1277 /* The instruction being stepped over triggers a nonsteppable
1278 watchpoint. If true, we'll skip inserting watchpoints. */
1279 int nonsteppable_watchpoint_p
;
1281 /* The thread's global number. */
1285 /* The step-over info of the location that is being stepped over.
1287 Note that with async/breakpoint always-inserted mode, a user might
1288 set a new breakpoint/watchpoint/etc. exactly while a breakpoint is
1289 being stepped over. As setting a new breakpoint inserts all
1290 breakpoints, we need to make sure the breakpoint being stepped over
1291 isn't inserted then. We do that by only clearing the step-over
1292 info when the step-over is actually finished (or aborted).
1294 Presently GDB can only step over one breakpoint at any given time.
1295 Given threads that can't run code in the same address space as the
1296 breakpoint's can't really miss the breakpoint, GDB could be taught
1297 to step-over at most one breakpoint per address space (so this info
1298 could move to the address space object if/when GDB is extended).
1299 The set of breakpoints being stepped over will normally be much
1300 smaller than the set of all breakpoints, so a flag in the
1301 breakpoint location structure would be wasteful. A separate list
1302 also saves complexity and run-time, as otherwise we'd have to go
1303 through all breakpoint locations clearing their flag whenever we
1304 start a new sequence. Similar considerations weigh against storing
1305 this info in the thread object. Plus, not all step overs actually
1306 have breakpoint locations -- e.g., stepping past a single-step
1307 breakpoint, or stepping to complete a non-continuable
1309 static struct step_over_info step_over_info
;
1311 /* Record the address of the breakpoint/instruction we're currently
1313 N.B. We record the aspace and address now, instead of say just the thread,
1314 because when we need the info later the thread may be running. */
1317 set_step_over_info (const address_space
*aspace
, CORE_ADDR address
,
1318 int nonsteppable_watchpoint_p
,
1321 step_over_info
.aspace
= aspace
;
1322 step_over_info
.address
= address
;
1323 step_over_info
.nonsteppable_watchpoint_p
= nonsteppable_watchpoint_p
;
1324 step_over_info
.thread
= thread
;
1327 /* Called when we're not longer stepping over a breakpoint / an
1328 instruction, so all breakpoints are free to be (re)inserted. */
1331 clear_step_over_info (void)
1334 fprintf_unfiltered (gdb_stdlog
,
1335 "infrun: clear_step_over_info\n");
1336 step_over_info
.aspace
= NULL
;
1337 step_over_info
.address
= 0;
1338 step_over_info
.nonsteppable_watchpoint_p
= 0;
1339 step_over_info
.thread
= -1;
1345 stepping_past_instruction_at (struct address_space
*aspace
,
1348 return (step_over_info
.aspace
!= NULL
1349 && breakpoint_address_match (aspace
, address
,
1350 step_over_info
.aspace
,
1351 step_over_info
.address
));
1357 thread_is_stepping_over_breakpoint (int thread
)
1359 return (step_over_info
.thread
!= -1
1360 && thread
== step_over_info
.thread
);
1366 stepping_past_nonsteppable_watchpoint (void)
1368 return step_over_info
.nonsteppable_watchpoint_p
;
1371 /* Returns true if step-over info is valid. */
1374 step_over_info_valid_p (void)
1376 return (step_over_info
.aspace
!= NULL
1377 || stepping_past_nonsteppable_watchpoint ());
1381 /* Displaced stepping. */
1383 /* In non-stop debugging mode, we must take special care to manage
1384 breakpoints properly; in particular, the traditional strategy for
1385 stepping a thread past a breakpoint it has hit is unsuitable.
1386 'Displaced stepping' is a tactic for stepping one thread past a
1387 breakpoint it has hit while ensuring that other threads running
1388 concurrently will hit the breakpoint as they should.
1390 The traditional way to step a thread T off a breakpoint in a
1391 multi-threaded program in all-stop mode is as follows:
1393 a0) Initially, all threads are stopped, and breakpoints are not
1395 a1) We single-step T, leaving breakpoints uninserted.
1396 a2) We insert breakpoints, and resume all threads.
1398 In non-stop debugging, however, this strategy is unsuitable: we
1399 don't want to have to stop all threads in the system in order to
1400 continue or step T past a breakpoint. Instead, we use displaced
1403 n0) Initially, T is stopped, other threads are running, and
1404 breakpoints are inserted.
1405 n1) We copy the instruction "under" the breakpoint to a separate
1406 location, outside the main code stream, making any adjustments
1407 to the instruction, register, and memory state as directed by
1409 n2) We single-step T over the instruction at its new location.
1410 n3) We adjust the resulting register and memory state as directed
1411 by T's architecture. This includes resetting T's PC to point
1412 back into the main instruction stream.
1415 This approach depends on the following gdbarch methods:
1417 - gdbarch_max_insn_length and gdbarch_displaced_step_location
1418 indicate where to copy the instruction, and how much space must
1419 be reserved there. We use these in step n1.
1421 - gdbarch_displaced_step_copy_insn copies a instruction to a new
1422 address, and makes any necessary adjustments to the instruction,
1423 register contents, and memory. We use this in step n1.
1425 - gdbarch_displaced_step_fixup adjusts registers and memory after
1426 we have successfully single-stepped the instruction, to yield the
1427 same effect the instruction would have had if we had executed it
1428 at its original address. We use this in step n3.
1430 The gdbarch_displaced_step_copy_insn and
1431 gdbarch_displaced_step_fixup functions must be written so that
1432 copying an instruction with gdbarch_displaced_step_copy_insn,
1433 single-stepping across the copied instruction, and then applying
1434 gdbarch_displaced_insn_fixup should have the same effects on the
1435 thread's memory and registers as stepping the instruction in place
1436 would have. Exactly which responsibilities fall to the copy and
1437 which fall to the fixup is up to the author of those functions.
1439 See the comments in gdbarch.sh for details.
1441 Note that displaced stepping and software single-step cannot
1442 currently be used in combination, although with some care I think
1443 they could be made to. Software single-step works by placing
1444 breakpoints on all possible subsequent instructions; if the
1445 displaced instruction is a PC-relative jump, those breakpoints
1446 could fall in very strange places --- on pages that aren't
1447 executable, or at addresses that are not proper instruction
1448 boundaries. (We do generally let other threads run while we wait
1449 to hit the software single-step breakpoint, and they might
1450 encounter such a corrupted instruction.) One way to work around
1451 this would be to have gdbarch_displaced_step_copy_insn fully
1452 simulate the effect of PC-relative instructions (and return NULL)
1453 on architectures that use software single-stepping.
1455 In non-stop mode, we can have independent and simultaneous step
1456 requests, so more than one thread may need to simultaneously step
1457 over a breakpoint. The current implementation assumes there is
1458 only one scratch space per process. In this case, we have to
1459 serialize access to the scratch space. If thread A wants to step
1460 over a breakpoint, but we are currently waiting for some other
1461 thread to complete a displaced step, we leave thread A stopped and
1462 place it in the displaced_step_request_queue. Whenever a displaced
1463 step finishes, we pick the next thread in the queue and start a new
1464 displaced step operation on it. See displaced_step_prepare and
1465 displaced_step_fixup for details. */
1467 /* Default destructor for displaced_step_closure. */
1469 displaced_step_closure::~displaced_step_closure () = default;
1471 /* Get the displaced stepping state of process PID. */
1473 static displaced_step_inferior_state
*
1474 get_displaced_stepping_state (inferior
*inf
)
1476 return &inf
->displaced_step_state
;
1479 /* Returns true if any inferior has a thread doing a displaced
1483 displaced_step_in_progress_any_inferior ()
1485 for (inferior
*i
: all_inferiors ())
1487 if (i
->displaced_step_state
.step_thread
!= nullptr)
1494 /* Return true if thread represented by PTID is doing a displaced
1498 displaced_step_in_progress_thread (thread_info
*thread
)
1500 gdb_assert (thread
!= NULL
);
1502 return get_displaced_stepping_state (thread
->inf
)->step_thread
== thread
;
1505 /* Return true if process PID has a thread doing a displaced step. */
1508 displaced_step_in_progress (inferior
*inf
)
1510 return get_displaced_stepping_state (inf
)->step_thread
!= nullptr;
1513 /* If inferior is in displaced stepping, and ADDR equals to starting address
1514 of copy area, return corresponding displaced_step_closure. Otherwise,
1517 struct displaced_step_closure
*
1518 get_displaced_step_closure_by_addr (CORE_ADDR addr
)
1520 displaced_step_inferior_state
*displaced
1521 = get_displaced_stepping_state (current_inferior ());
1523 /* If checking the mode of displaced instruction in copy area. */
1524 if (displaced
->step_thread
!= nullptr
1525 && displaced
->step_copy
== addr
)
1526 return displaced
->step_closure
;
1532 infrun_inferior_exit (struct inferior
*inf
)
1534 inf
->displaced_step_state
.reset ();
1537 /* If ON, and the architecture supports it, GDB will use displaced
1538 stepping to step over breakpoints. If OFF, or if the architecture
1539 doesn't support it, GDB will instead use the traditional
1540 hold-and-step approach. If AUTO (which is the default), GDB will
1541 decide which technique to use to step over breakpoints depending on
1542 which of all-stop or non-stop mode is active --- displaced stepping
1543 in non-stop mode; hold-and-step in all-stop mode. */
1545 static enum auto_boolean can_use_displaced_stepping
= AUTO_BOOLEAN_AUTO
;
1548 show_can_use_displaced_stepping (struct ui_file
*file
, int from_tty
,
1549 struct cmd_list_element
*c
,
1552 if (can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
)
1553 fprintf_filtered (file
,
1554 _("Debugger's willingness to use displaced stepping "
1555 "to step over breakpoints is %s (currently %s).\n"),
1556 value
, target_is_non_stop_p () ? "on" : "off");
1558 fprintf_filtered (file
,
1559 _("Debugger's willingness to use displaced stepping "
1560 "to step over breakpoints is %s.\n"), value
);
1563 /* Return non-zero if displaced stepping can/should be used to step
1564 over breakpoints of thread TP. */
1567 use_displaced_stepping (struct thread_info
*tp
)
1569 struct regcache
*regcache
= get_thread_regcache (tp
);
1570 struct gdbarch
*gdbarch
= regcache
->arch ();
1571 displaced_step_inferior_state
*displaced_state
1572 = get_displaced_stepping_state (tp
->inf
);
1574 return (((can_use_displaced_stepping
== AUTO_BOOLEAN_AUTO
1575 && target_is_non_stop_p ())
1576 || can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1577 && gdbarch_displaced_step_copy_insn_p (gdbarch
)
1578 && find_record_target () == NULL
1579 && !displaced_state
->failed_before
);
1582 /* Clean out any stray displaced stepping state. */
1584 displaced_step_clear (struct displaced_step_inferior_state
*displaced
)
1586 /* Indicate that there is no cleanup pending. */
1587 displaced
->step_thread
= nullptr;
1589 delete displaced
->step_closure
;
1590 displaced
->step_closure
= NULL
;
1593 /* A cleanup that wraps displaced_step_clear. */
1594 using displaced_step_clear_cleanup
1595 = FORWARD_SCOPE_EXIT (displaced_step_clear
);
1597 /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
1599 displaced_step_dump_bytes (struct ui_file
*file
,
1600 const gdb_byte
*buf
,
1605 for (i
= 0; i
< len
; i
++)
1606 fprintf_unfiltered (file
, "%02x ", buf
[i
]);
1607 fputs_unfiltered ("\n", file
);
1610 /* Prepare to single-step, using displaced stepping.
1612 Note that we cannot use displaced stepping when we have a signal to
1613 deliver. If we have a signal to deliver and an instruction to step
1614 over, then after the step, there will be no indication from the
1615 target whether the thread entered a signal handler or ignored the
1616 signal and stepped over the instruction successfully --- both cases
1617 result in a simple SIGTRAP. In the first case we mustn't do a
1618 fixup, and in the second case we must --- but we can't tell which.
1619 Comments in the code for 'random signals' in handle_inferior_event
1620 explain how we handle this case instead.
1622 Returns 1 if preparing was successful -- this thread is going to be
1623 stepped now; 0 if displaced stepping this thread got queued; or -1
1624 if this instruction can't be displaced stepped. */
1627 displaced_step_prepare_throw (thread_info
*tp
)
1629 regcache
*regcache
= get_thread_regcache (tp
);
1630 struct gdbarch
*gdbarch
= regcache
->arch ();
1631 const address_space
*aspace
= regcache
->aspace ();
1632 CORE_ADDR original
, copy
;
1634 struct displaced_step_closure
*closure
;
1637 /* We should never reach this function if the architecture does not
1638 support displaced stepping. */
1639 gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch
));
1641 /* Nor if the thread isn't meant to step over a breakpoint. */
1642 gdb_assert (tp
->control
.trap_expected
);
1644 /* Disable range stepping while executing in the scratch pad. We
1645 want a single-step even if executing the displaced instruction in
1646 the scratch buffer lands within the stepping range (e.g., a
1648 tp
->control
.may_range_step
= 0;
1650 /* We have to displaced step one thread at a time, as we only have
1651 access to a single scratch space per inferior. */
1653 displaced_step_inferior_state
*displaced
1654 = get_displaced_stepping_state (tp
->inf
);
1656 if (displaced
->step_thread
!= nullptr)
1658 /* Already waiting for a displaced step to finish. Defer this
1659 request and place in queue. */
1661 if (debug_displaced
)
1662 fprintf_unfiltered (gdb_stdlog
,
1663 "displaced: deferring step of %s\n",
1664 target_pid_to_str (tp
->ptid
).c_str ());
1666 thread_step_over_chain_enqueue (tp
);
1671 if (debug_displaced
)
1672 fprintf_unfiltered (gdb_stdlog
,
1673 "displaced: stepping %s now\n",
1674 target_pid_to_str (tp
->ptid
).c_str ());
1677 displaced_step_clear (displaced
);
1679 scoped_restore_current_thread restore_thread
;
1681 switch_to_thread (tp
);
1683 original
= regcache_read_pc (regcache
);
1685 copy
= gdbarch_displaced_step_location (gdbarch
);
1686 len
= gdbarch_max_insn_length (gdbarch
);
1688 if (breakpoint_in_range_p (aspace
, copy
, len
))
1690 /* There's a breakpoint set in the scratch pad location range
1691 (which is usually around the entry point). We'd either
1692 install it before resuming, which would overwrite/corrupt the
1693 scratch pad, or if it was already inserted, this displaced
1694 step would overwrite it. The latter is OK in the sense that
1695 we already assume that no thread is going to execute the code
1696 in the scratch pad range (after initial startup) anyway, but
1697 the former is unacceptable. Simply punt and fallback to
1698 stepping over this breakpoint in-line. */
1699 if (debug_displaced
)
1701 fprintf_unfiltered (gdb_stdlog
,
1702 "displaced: breakpoint set in scratch pad. "
1703 "Stepping over breakpoint in-line instead.\n");
1709 /* Save the original contents of the copy area. */
1710 displaced
->step_saved_copy
.resize (len
);
1711 status
= target_read_memory (copy
, displaced
->step_saved_copy
.data (), len
);
1713 throw_error (MEMORY_ERROR
,
1714 _("Error accessing memory address %s (%s) for "
1715 "displaced-stepping scratch space."),
1716 paddress (gdbarch
, copy
), safe_strerror (status
));
1717 if (debug_displaced
)
1719 fprintf_unfiltered (gdb_stdlog
, "displaced: saved %s: ",
1720 paddress (gdbarch
, copy
));
1721 displaced_step_dump_bytes (gdb_stdlog
,
1722 displaced
->step_saved_copy
.data (),
1726 closure
= gdbarch_displaced_step_copy_insn (gdbarch
,
1727 original
, copy
, regcache
);
1728 if (closure
== NULL
)
1730 /* The architecture doesn't know how or want to displaced step
1731 this instruction or instruction sequence. Fallback to
1732 stepping over the breakpoint in-line. */
1736 /* Save the information we need to fix things up if the step
1738 displaced
->step_thread
= tp
;
1739 displaced
->step_gdbarch
= gdbarch
;
1740 displaced
->step_closure
= closure
;
1741 displaced
->step_original
= original
;
1742 displaced
->step_copy
= copy
;
1745 displaced_step_clear_cleanup
cleanup (displaced
);
1747 /* Resume execution at the copy. */
1748 regcache_write_pc (regcache
, copy
);
1753 if (debug_displaced
)
1754 fprintf_unfiltered (gdb_stdlog
, "displaced: displaced pc to %s\n",
1755 paddress (gdbarch
, copy
));
1760 /* Wrapper for displaced_step_prepare_throw that disabled further
1761 attempts at displaced stepping if we get a memory error. */
1764 displaced_step_prepare (thread_info
*thread
)
1770 prepared
= displaced_step_prepare_throw (thread
);
1772 catch (const gdb_exception_error
&ex
)
1774 struct displaced_step_inferior_state
*displaced_state
;
1776 if (ex
.error
!= MEMORY_ERROR
1777 && ex
.error
!= NOT_SUPPORTED_ERROR
)
1782 fprintf_unfiltered (gdb_stdlog
,
1783 "infrun: disabling displaced stepping: %s\n",
1787 /* Be verbose if "set displaced-stepping" is "on", silent if
1789 if (can_use_displaced_stepping
== AUTO_BOOLEAN_TRUE
)
1791 warning (_("disabling displaced stepping: %s"),
1795 /* Disable further displaced stepping attempts. */
1797 = get_displaced_stepping_state (thread
->inf
);
1798 displaced_state
->failed_before
= 1;
1805 write_memory_ptid (ptid_t ptid
, CORE_ADDR memaddr
,
1806 const gdb_byte
*myaddr
, int len
)
1808 scoped_restore save_inferior_ptid
= make_scoped_restore (&inferior_ptid
);
1810 inferior_ptid
= ptid
;
1811 write_memory (memaddr
, myaddr
, len
);
1814 /* Restore the contents of the copy area for thread PTID. */
1817 displaced_step_restore (struct displaced_step_inferior_state
*displaced
,
1820 ULONGEST len
= gdbarch_max_insn_length (displaced
->step_gdbarch
);
1822 write_memory_ptid (ptid
, displaced
->step_copy
,
1823 displaced
->step_saved_copy
.data (), len
);
1824 if (debug_displaced
)
1825 fprintf_unfiltered (gdb_stdlog
, "displaced: restored %s %s\n",
1826 target_pid_to_str (ptid
).c_str (),
1827 paddress (displaced
->step_gdbarch
,
1828 displaced
->step_copy
));
1831 /* If we displaced stepped an instruction successfully, adjust
1832 registers and memory to yield the same effect the instruction would
1833 have had if we had executed it at its original address, and return
1834 1. If the instruction didn't complete, relocate the PC and return
1835 -1. If the thread wasn't displaced stepping, return 0. */
1838 displaced_step_fixup (thread_info
*event_thread
, enum gdb_signal signal
)
1840 struct displaced_step_inferior_state
*displaced
1841 = get_displaced_stepping_state (event_thread
->inf
);
1844 /* Was this event for the thread we displaced? */
1845 if (displaced
->step_thread
!= event_thread
)
1848 displaced_step_clear_cleanup
cleanup (displaced
);
1850 displaced_step_restore (displaced
, displaced
->step_thread
->ptid
);
1852 /* Fixup may need to read memory/registers. Switch to the thread
1853 that we're fixing up. Also, target_stopped_by_watchpoint checks
1854 the current thread. */
1855 switch_to_thread (event_thread
);
1857 /* Did the instruction complete successfully? */
1858 if (signal
== GDB_SIGNAL_TRAP
1859 && !(target_stopped_by_watchpoint ()
1860 && (gdbarch_have_nonsteppable_watchpoint (displaced
->step_gdbarch
)
1861 || target_have_steppable_watchpoint
)))
1863 /* Fix up the resulting state. */
1864 gdbarch_displaced_step_fixup (displaced
->step_gdbarch
,
1865 displaced
->step_closure
,
1866 displaced
->step_original
,
1867 displaced
->step_copy
,
1868 get_thread_regcache (displaced
->step_thread
));
1873 /* Since the instruction didn't complete, all we can do is
1875 struct regcache
*regcache
= get_thread_regcache (event_thread
);
1876 CORE_ADDR pc
= regcache_read_pc (regcache
);
1878 pc
= displaced
->step_original
+ (pc
- displaced
->step_copy
);
1879 regcache_write_pc (regcache
, pc
);
1886 /* Data to be passed around while handling an event. This data is
1887 discarded between events. */
1888 struct execution_control_state
1891 /* The thread that got the event, if this was a thread event; NULL
1893 struct thread_info
*event_thread
;
1895 struct target_waitstatus ws
;
1896 int stop_func_filled_in
;
1897 CORE_ADDR stop_func_start
;
1898 CORE_ADDR stop_func_end
;
1899 const char *stop_func_name
;
1902 /* True if the event thread hit the single-step breakpoint of
1903 another thread. Thus the event doesn't cause a stop, the thread
1904 needs to be single-stepped past the single-step breakpoint before
1905 we can switch back to the original stepping thread. */
1906 int hit_singlestep_breakpoint
;
1909 /* Clear ECS and set it to point at TP. */
1912 reset_ecs (struct execution_control_state
*ecs
, struct thread_info
*tp
)
1914 memset (ecs
, 0, sizeof (*ecs
));
1915 ecs
->event_thread
= tp
;
1916 ecs
->ptid
= tp
->ptid
;
1919 static void keep_going_pass_signal (struct execution_control_state
*ecs
);
1920 static void prepare_to_wait (struct execution_control_state
*ecs
);
1921 static int keep_going_stepped_thread (struct thread_info
*tp
);
1922 static step_over_what
thread_still_needs_step_over (struct thread_info
*tp
);
1924 /* Are there any pending step-over requests? If so, run all we can
1925 now and return true. Otherwise, return false. */
1928 start_step_over (void)
1930 struct thread_info
*tp
, *next
;
1932 /* Don't start a new step-over if we already have an in-line
1933 step-over operation ongoing. */
1934 if (step_over_info_valid_p ())
1937 for (tp
= step_over_queue_head
; tp
!= NULL
; tp
= next
)
1939 struct execution_control_state ecss
;
1940 struct execution_control_state
*ecs
= &ecss
;
1941 step_over_what step_what
;
1942 int must_be_in_line
;
1944 gdb_assert (!tp
->stop_requested
);
1946 next
= thread_step_over_chain_next (tp
);
1948 /* If this inferior already has a displaced step in process,
1949 don't start a new one. */
1950 if (displaced_step_in_progress (tp
->inf
))
1953 step_what
= thread_still_needs_step_over (tp
);
1954 must_be_in_line
= ((step_what
& STEP_OVER_WATCHPOINT
)
1955 || ((step_what
& STEP_OVER_BREAKPOINT
)
1956 && !use_displaced_stepping (tp
)));
1958 /* We currently stop all threads of all processes to step-over
1959 in-line. If we need to start a new in-line step-over, let
1960 any pending displaced steps finish first. */
1961 if (must_be_in_line
&& displaced_step_in_progress_any_inferior ())
1964 thread_step_over_chain_remove (tp
);
1966 if (step_over_queue_head
== NULL
)
1969 fprintf_unfiltered (gdb_stdlog
,
1970 "infrun: step-over queue now empty\n");
1973 if (tp
->control
.trap_expected
1977 internal_error (__FILE__
, __LINE__
,
1978 "[%s] has inconsistent state: "
1979 "trap_expected=%d, resumed=%d, executing=%d\n",
1980 target_pid_to_str (tp
->ptid
).c_str (),
1981 tp
->control
.trap_expected
,
1987 fprintf_unfiltered (gdb_stdlog
,
1988 "infrun: resuming [%s] for step-over\n",
1989 target_pid_to_str (tp
->ptid
).c_str ());
1991 /* keep_going_pass_signal skips the step-over if the breakpoint
1992 is no longer inserted. In all-stop, we want to keep looking
1993 for a thread that needs a step-over instead of resuming TP,
1994 because we wouldn't be able to resume anything else until the
1995 target stops again. In non-stop, the resume always resumes
1996 only TP, so it's OK to let the thread resume freely. */
1997 if (!target_is_non_stop_p () && !step_what
)
2000 switch_to_thread (tp
);
2001 reset_ecs (ecs
, tp
);
2002 keep_going_pass_signal (ecs
);
2004 if (!ecs
->wait_some_more
)
2005 error (_("Command aborted."));
2007 gdb_assert (tp
->resumed
);
2009 /* If we started a new in-line step-over, we're done. */
2010 if (step_over_info_valid_p ())
2012 gdb_assert (tp
->control
.trap_expected
);
2016 if (!target_is_non_stop_p ())
2018 /* On all-stop, shouldn't have resumed unless we needed a
2020 gdb_assert (tp
->control
.trap_expected
2021 || tp
->step_after_step_resume_breakpoint
);
2023 /* With remote targets (at least), in all-stop, we can't
2024 issue any further remote commands until the program stops
2029 /* Either the thread no longer needed a step-over, or a new
2030 displaced stepping sequence started. Even in the latter
2031 case, continue looking. Maybe we can also start another
2032 displaced step on a thread of other process. */
2038 /* Update global variables holding ptids to hold NEW_PTID if they were
2039 holding OLD_PTID. */
2041 infrun_thread_ptid_changed (ptid_t old_ptid
, ptid_t new_ptid
)
2043 if (inferior_ptid
== old_ptid
)
2044 inferior_ptid
= new_ptid
;
2049 static const char schedlock_off
[] = "off";
2050 static const char schedlock_on
[] = "on";
2051 static const char schedlock_step
[] = "step";
2052 static const char schedlock_replay
[] = "replay";
2053 static const char *const scheduler_enums
[] = {
2060 static const char *scheduler_mode
= schedlock_replay
;
2062 show_scheduler_mode (struct ui_file
*file
, int from_tty
,
2063 struct cmd_list_element
*c
, const char *value
)
2065 fprintf_filtered (file
,
2066 _("Mode for locking scheduler "
2067 "during execution is \"%s\".\n"),
2072 set_schedlock_func (const char *args
, int from_tty
, struct cmd_list_element
*c
)
2074 if (!target_can_lock_scheduler
)
2076 scheduler_mode
= schedlock_off
;
2077 error (_("Target '%s' cannot support this command."), target_shortname
);
2081 /* True if execution commands resume all threads of all processes by
2082 default; otherwise, resume only threads of the current inferior
2084 bool sched_multi
= false;
2086 /* Try to setup for software single stepping over the specified location.
2087 Return 1 if target_resume() should use hardware single step.
2089 GDBARCH the current gdbarch.
2090 PC the location to step over. */
2093 maybe_software_singlestep (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
2097 if (execution_direction
== EXEC_FORWARD
2098 && gdbarch_software_single_step_p (gdbarch
))
2099 hw_step
= !insert_single_step_breakpoints (gdbarch
);
2107 user_visible_resume_ptid (int step
)
2113 /* With non-stop mode on, threads are always handled
2115 resume_ptid
= inferior_ptid
;
2117 else if ((scheduler_mode
== schedlock_on
)
2118 || (scheduler_mode
== schedlock_step
&& step
))
2120 /* User-settable 'scheduler' mode requires solo thread
2122 resume_ptid
= inferior_ptid
;
2124 else if ((scheduler_mode
== schedlock_replay
)
2125 && target_record_will_replay (minus_one_ptid
, execution_direction
))
2127 /* User-settable 'scheduler' mode requires solo thread resume in replay
2129 resume_ptid
= inferior_ptid
;
2131 else if (!sched_multi
&& target_supports_multi_process ())
2133 /* Resume all threads of the current process (and none of other
2135 resume_ptid
= ptid_t (inferior_ptid
.pid ());
2139 /* Resume all threads of all processes. */
2140 resume_ptid
= RESUME_ALL
;
2146 /* Return a ptid representing the set of threads that we will resume,
2147 in the perspective of the target, assuming run control handling
2148 does not require leaving some threads stopped (e.g., stepping past
2149 breakpoint). USER_STEP indicates whether we're about to start the
2150 target for a stepping command. */
2153 internal_resume_ptid (int user_step
)
2155 /* In non-stop, we always control threads individually. Note that
2156 the target may always work in non-stop mode even with "set
2157 non-stop off", in which case user_visible_resume_ptid could
2158 return a wildcard ptid. */
2159 if (target_is_non_stop_p ())
2160 return inferior_ptid
;
2162 return user_visible_resume_ptid (user_step
);
2165 /* Wrapper for target_resume, that handles infrun-specific
2169 do_target_resume (ptid_t resume_ptid
, int step
, enum gdb_signal sig
)
2171 struct thread_info
*tp
= inferior_thread ();
2173 gdb_assert (!tp
->stop_requested
);
2175 /* Install inferior's terminal modes. */
2176 target_terminal::inferior ();
2178 /* Avoid confusing the next resume, if the next stop/resume
2179 happens to apply to another thread. */
2180 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2182 /* Advise target which signals may be handled silently.
2184 If we have removed breakpoints because we are stepping over one
2185 in-line (in any thread), we need to receive all signals to avoid
2186 accidentally skipping a breakpoint during execution of a signal
2189 Likewise if we're displaced stepping, otherwise a trap for a
2190 breakpoint in a signal handler might be confused with the
2191 displaced step finishing. We don't make the displaced_step_fixup
2192 step distinguish the cases instead, because:
2194 - a backtrace while stopped in the signal handler would show the
2195 scratch pad as frame older than the signal handler, instead of
2196 the real mainline code.
2198 - when the thread is later resumed, the signal handler would
2199 return to the scratch pad area, which would no longer be
2201 if (step_over_info_valid_p ()
2202 || displaced_step_in_progress (tp
->inf
))
2203 target_pass_signals ({});
2205 target_pass_signals (signal_pass
);
2207 target_resume (resume_ptid
, step
, sig
);
2209 target_commit_resume ();
2212 /* Resume the inferior. SIG is the signal to give the inferior
2213 (GDB_SIGNAL_0 for none). Note: don't call this directly; instead
2214 call 'resume', which handles exceptions. */
2217 resume_1 (enum gdb_signal sig
)
2219 struct regcache
*regcache
= get_current_regcache ();
2220 struct gdbarch
*gdbarch
= regcache
->arch ();
2221 struct thread_info
*tp
= inferior_thread ();
2222 CORE_ADDR pc
= regcache_read_pc (regcache
);
2223 const address_space
*aspace
= regcache
->aspace ();
2225 /* This represents the user's step vs continue request. When
2226 deciding whether "set scheduler-locking step" applies, it's the
2227 user's intention that counts. */
2228 const int user_step
= tp
->control
.stepping_command
;
2229 /* This represents what we'll actually request the target to do.
2230 This can decay from a step to a continue, if e.g., we need to
2231 implement single-stepping with breakpoints (software
2235 gdb_assert (!tp
->stop_requested
);
2236 gdb_assert (!thread_is_in_step_over_chain (tp
));
2238 if (tp
->suspend
.waitstatus_pending_p
)
2243 = target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2245 fprintf_unfiltered (gdb_stdlog
,
2246 "infrun: resume: thread %s has pending wait "
2247 "status %s (currently_stepping=%d).\n",
2248 target_pid_to_str (tp
->ptid
).c_str (),
2250 currently_stepping (tp
));
2255 /* FIXME: What should we do if we are supposed to resume this
2256 thread with a signal? Maybe we should maintain a queue of
2257 pending signals to deliver. */
2258 if (sig
!= GDB_SIGNAL_0
)
2260 warning (_("Couldn't deliver signal %s to %s."),
2261 gdb_signal_to_name (sig
),
2262 target_pid_to_str (tp
->ptid
).c_str ());
2265 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2267 if (target_can_async_p ())
2270 /* Tell the event loop we have an event to process. */
2271 mark_async_event_handler (infrun_async_inferior_event_token
);
2276 tp
->stepped_breakpoint
= 0;
2278 /* Depends on stepped_breakpoint. */
2279 step
= currently_stepping (tp
);
2281 if (current_inferior ()->waiting_for_vfork_done
)
2283 /* Don't try to single-step a vfork parent that is waiting for
2284 the child to get out of the shared memory region (by exec'ing
2285 or exiting). This is particularly important on software
2286 single-step archs, as the child process would trip on the
2287 software single step breakpoint inserted for the parent
2288 process. Since the parent will not actually execute any
2289 instruction until the child is out of the shared region (such
2290 are vfork's semantics), it is safe to simply continue it.
2291 Eventually, we'll see a TARGET_WAITKIND_VFORK_DONE event for
2292 the parent, and tell it to `keep_going', which automatically
2293 re-sets it stepping. */
2295 fprintf_unfiltered (gdb_stdlog
,
2296 "infrun: resume : clear step\n");
2301 fprintf_unfiltered (gdb_stdlog
,
2302 "infrun: resume (step=%d, signal=%s), "
2303 "trap_expected=%d, current thread [%s] at %s\n",
2304 step
, gdb_signal_to_symbol_string (sig
),
2305 tp
->control
.trap_expected
,
2306 target_pid_to_str (inferior_ptid
).c_str (),
2307 paddress (gdbarch
, pc
));
2309 /* Normally, by the time we reach `resume', the breakpoints are either
2310 removed or inserted, as appropriate. The exception is if we're sitting
2311 at a permanent breakpoint; we need to step over it, but permanent
2312 breakpoints can't be removed. So we have to test for it here. */
2313 if (breakpoint_here_p (aspace
, pc
) == permanent_breakpoint_here
)
2315 if (sig
!= GDB_SIGNAL_0
)
2317 /* We have a signal to pass to the inferior. The resume
2318 may, or may not take us to the signal handler. If this
2319 is a step, we'll need to stop in the signal handler, if
2320 there's one, (if the target supports stepping into
2321 handlers), or in the next mainline instruction, if
2322 there's no handler. If this is a continue, we need to be
2323 sure to run the handler with all breakpoints inserted.
2324 In all cases, set a breakpoint at the current address
2325 (where the handler returns to), and once that breakpoint
2326 is hit, resume skipping the permanent breakpoint. If
2327 that breakpoint isn't hit, then we've stepped into the
2328 signal handler (or hit some other event). We'll delete
2329 the step-resume breakpoint then. */
2332 fprintf_unfiltered (gdb_stdlog
,
2333 "infrun: resume: skipping permanent breakpoint, "
2334 "deliver signal first\n");
2336 clear_step_over_info ();
2337 tp
->control
.trap_expected
= 0;
2339 if (tp
->control
.step_resume_breakpoint
== NULL
)
2341 /* Set a "high-priority" step-resume, as we don't want
2342 user breakpoints at PC to trigger (again) when this
2344 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2345 gdb_assert (tp
->control
.step_resume_breakpoint
->loc
->permanent
);
2347 tp
->step_after_step_resume_breakpoint
= step
;
2350 insert_breakpoints ();
2354 /* There's no signal to pass, we can go ahead and skip the
2355 permanent breakpoint manually. */
2357 fprintf_unfiltered (gdb_stdlog
,
2358 "infrun: resume: skipping permanent breakpoint\n");
2359 gdbarch_skip_permanent_breakpoint (gdbarch
, regcache
);
2360 /* Update pc to reflect the new address from which we will
2361 execute instructions. */
2362 pc
= regcache_read_pc (regcache
);
2366 /* We've already advanced the PC, so the stepping part
2367 is done. Now we need to arrange for a trap to be
2368 reported to handle_inferior_event. Set a breakpoint
2369 at the current PC, and run to it. Don't update
2370 prev_pc, because if we end in
2371 switch_back_to_stepped_thread, we want the "expected
2372 thread advanced also" branch to be taken. IOW, we
2373 don't want this thread to step further from PC
2375 gdb_assert (!step_over_info_valid_p ());
2376 insert_single_step_breakpoint (gdbarch
, aspace
, pc
);
2377 insert_breakpoints ();
2379 resume_ptid
= internal_resume_ptid (user_step
);
2380 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
2387 /* If we have a breakpoint to step over, make sure to do a single
2388 step only. Same if we have software watchpoints. */
2389 if (tp
->control
.trap_expected
|| bpstat_should_step ())
2390 tp
->control
.may_range_step
= 0;
2392 /* If enabled, step over breakpoints by executing a copy of the
2393 instruction at a different address.
2395 We can't use displaced stepping when we have a signal to deliver;
2396 the comments for displaced_step_prepare explain why. The
2397 comments in the handle_inferior event for dealing with 'random
2398 signals' explain what we do instead.
2400 We can't use displaced stepping when we are waiting for vfork_done
2401 event, displaced stepping breaks the vfork child similarly as single
2402 step software breakpoint. */
2403 if (tp
->control
.trap_expected
2404 && use_displaced_stepping (tp
)
2405 && !step_over_info_valid_p ()
2406 && sig
== GDB_SIGNAL_0
2407 && !current_inferior ()->waiting_for_vfork_done
)
2409 int prepared
= displaced_step_prepare (tp
);
2414 fprintf_unfiltered (gdb_stdlog
,
2415 "Got placed in step-over queue\n");
2417 tp
->control
.trap_expected
= 0;
2420 else if (prepared
< 0)
2422 /* Fallback to stepping over the breakpoint in-line. */
2424 if (target_is_non_stop_p ())
2425 stop_all_threads ();
2427 set_step_over_info (regcache
->aspace (),
2428 regcache_read_pc (regcache
), 0, tp
->global_num
);
2430 step
= maybe_software_singlestep (gdbarch
, pc
);
2432 insert_breakpoints ();
2434 else if (prepared
> 0)
2436 struct displaced_step_inferior_state
*displaced
;
2438 /* Update pc to reflect the new address from which we will
2439 execute instructions due to displaced stepping. */
2440 pc
= regcache_read_pc (get_thread_regcache (tp
));
2442 displaced
= get_displaced_stepping_state (tp
->inf
);
2443 step
= gdbarch_displaced_step_hw_singlestep (gdbarch
,
2444 displaced
->step_closure
);
2448 /* Do we need to do it the hard way, w/temp breakpoints? */
2450 step
= maybe_software_singlestep (gdbarch
, pc
);
2452 /* Currently, our software single-step implementation leads to different
2453 results than hardware single-stepping in one situation: when stepping
2454 into delivering a signal which has an associated signal handler,
2455 hardware single-step will stop at the first instruction of the handler,
2456 while software single-step will simply skip execution of the handler.
2458 For now, this difference in behavior is accepted since there is no
2459 easy way to actually implement single-stepping into a signal handler
2460 without kernel support.
2462 However, there is one scenario where this difference leads to follow-on
2463 problems: if we're stepping off a breakpoint by removing all breakpoints
2464 and then single-stepping. In this case, the software single-step
2465 behavior means that even if there is a *breakpoint* in the signal
2466 handler, GDB still would not stop.
2468 Fortunately, we can at least fix this particular issue. We detect
2469 here the case where we are about to deliver a signal while software
2470 single-stepping with breakpoints removed. In this situation, we
2471 revert the decisions to remove all breakpoints and insert single-
2472 step breakpoints, and instead we install a step-resume breakpoint
2473 at the current address, deliver the signal without stepping, and
2474 once we arrive back at the step-resume breakpoint, actually step
2475 over the breakpoint we originally wanted to step over. */
2476 if (thread_has_single_step_breakpoints_set (tp
)
2477 && sig
!= GDB_SIGNAL_0
2478 && step_over_info_valid_p ())
2480 /* If we have nested signals or a pending signal is delivered
2481 immediately after a handler returns, might might already have
2482 a step-resume breakpoint set on the earlier handler. We cannot
2483 set another step-resume breakpoint; just continue on until the
2484 original breakpoint is hit. */
2485 if (tp
->control
.step_resume_breakpoint
== NULL
)
2487 insert_hp_step_resume_breakpoint_at_frame (get_current_frame ());
2488 tp
->step_after_step_resume_breakpoint
= 1;
2491 delete_single_step_breakpoints (tp
);
2493 clear_step_over_info ();
2494 tp
->control
.trap_expected
= 0;
2496 insert_breakpoints ();
2499 /* If STEP is set, it's a request to use hardware stepping
2500 facilities. But in that case, we should never
2501 use singlestep breakpoint. */
2502 gdb_assert (!(thread_has_single_step_breakpoints_set (tp
) && step
));
2504 /* Decide the set of threads to ask the target to resume. */
2505 if (tp
->control
.trap_expected
)
2507 /* We're allowing a thread to run past a breakpoint it has
2508 hit, either by single-stepping the thread with the breakpoint
2509 removed, or by displaced stepping, with the breakpoint inserted.
2510 In the former case, we need to single-step only this thread,
2511 and keep others stopped, as they can miss this breakpoint if
2512 allowed to run. That's not really a problem for displaced
2513 stepping, but, we still keep other threads stopped, in case
2514 another thread is also stopped for a breakpoint waiting for
2515 its turn in the displaced stepping queue. */
2516 resume_ptid
= inferior_ptid
;
2519 resume_ptid
= internal_resume_ptid (user_step
);
2521 if (execution_direction
!= EXEC_REVERSE
2522 && step
&& breakpoint_inserted_here_p (aspace
, pc
))
2524 /* There are two cases where we currently need to step a
2525 breakpoint instruction when we have a signal to deliver:
2527 - See handle_signal_stop where we handle random signals that
2528 could take out us out of the stepping range. Normally, in
2529 that case we end up continuing (instead of stepping) over the
2530 signal handler with a breakpoint at PC, but there are cases
2531 where we should _always_ single-step, even if we have a
2532 step-resume breakpoint, like when a software watchpoint is
2533 set. Assuming single-stepping and delivering a signal at the
2534 same time would takes us to the signal handler, then we could
2535 have removed the breakpoint at PC to step over it. However,
2536 some hardware step targets (like e.g., Mac OS) can't step
2537 into signal handlers, and for those, we need to leave the
2538 breakpoint at PC inserted, as otherwise if the handler
2539 recurses and executes PC again, it'll miss the breakpoint.
2540 So we leave the breakpoint inserted anyway, but we need to
2541 record that we tried to step a breakpoint instruction, so
2542 that adjust_pc_after_break doesn't end up confused.
2544 - In non-stop if we insert a breakpoint (e.g., a step-resume)
2545 in one thread after another thread that was stepping had been
2546 momentarily paused for a step-over. When we re-resume the
2547 stepping thread, it may be resumed from that address with a
2548 breakpoint that hasn't trapped yet. Seen with
2549 gdb.threads/non-stop-fair-events.exp, on targets that don't
2550 do displaced stepping. */
2553 fprintf_unfiltered (gdb_stdlog
,
2554 "infrun: resume: [%s] stepped breakpoint\n",
2555 target_pid_to_str (tp
->ptid
).c_str ());
2557 tp
->stepped_breakpoint
= 1;
2559 /* Most targets can step a breakpoint instruction, thus
2560 executing it normally. But if this one cannot, just
2561 continue and we will hit it anyway. */
2562 if (gdbarch_cannot_step_breakpoint (gdbarch
))
2567 && tp
->control
.trap_expected
2568 && use_displaced_stepping (tp
)
2569 && !step_over_info_valid_p ())
2571 struct regcache
*resume_regcache
= get_thread_regcache (tp
);
2572 struct gdbarch
*resume_gdbarch
= resume_regcache
->arch ();
2573 CORE_ADDR actual_pc
= regcache_read_pc (resume_regcache
);
2576 fprintf_unfiltered (gdb_stdlog
, "displaced: run %s: ",
2577 paddress (resume_gdbarch
, actual_pc
));
2578 read_memory (actual_pc
, buf
, sizeof (buf
));
2579 displaced_step_dump_bytes (gdb_stdlog
, buf
, sizeof (buf
));
2582 if (tp
->control
.may_range_step
)
2584 /* If we're resuming a thread with the PC out of the step
2585 range, then we're doing some nested/finer run control
2586 operation, like stepping the thread out of the dynamic
2587 linker or the displaced stepping scratch pad. We
2588 shouldn't have allowed a range step then. */
2589 gdb_assert (pc_in_thread_step_range (pc
, tp
));
2592 do_target_resume (resume_ptid
, step
, sig
);
2596 /* Resume the inferior. SIG is the signal to give the inferior
2597 (GDB_SIGNAL_0 for none). This is a wrapper around 'resume_1' that
2598 rolls back state on error. */
2601 resume (gdb_signal sig
)
2607 catch (const gdb_exception
&ex
)
2609 /* If resuming is being aborted for any reason, delete any
2610 single-step breakpoint resume_1 may have created, to avoid
2611 confusing the following resumption, and to avoid leaving
2612 single-step breakpoints perturbing other threads, in case
2613 we're running in non-stop mode. */
2614 if (inferior_ptid
!= null_ptid
)
2615 delete_single_step_breakpoints (inferior_thread ());
2625 /* Counter that tracks number of user visible stops. This can be used
2626 to tell whether a command has proceeded the inferior past the
2627 current location. This allows e.g., inferior function calls in
2628 breakpoint commands to not interrupt the command list. When the
2629 call finishes successfully, the inferior is standing at the same
2630 breakpoint as if nothing happened (and so we don't call
2632 static ULONGEST current_stop_id
;
2639 return current_stop_id
;
2642 /* Called when we report a user visible stop. */
2650 /* Clear out all variables saying what to do when inferior is continued.
2651 First do this, then set the ones you want, then call `proceed'. */
2654 clear_proceed_status_thread (struct thread_info
*tp
)
2657 fprintf_unfiltered (gdb_stdlog
,
2658 "infrun: clear_proceed_status_thread (%s)\n",
2659 target_pid_to_str (tp
->ptid
).c_str ());
2661 /* If we're starting a new sequence, then the previous finished
2662 single-step is no longer relevant. */
2663 if (tp
->suspend
.waitstatus_pending_p
)
2665 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
2668 fprintf_unfiltered (gdb_stdlog
,
2669 "infrun: clear_proceed_status: pending "
2670 "event of %s was a finished step. "
2672 target_pid_to_str (tp
->ptid
).c_str ());
2674 tp
->suspend
.waitstatus_pending_p
= 0;
2675 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2677 else if (debug_infrun
)
2680 = target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
2682 fprintf_unfiltered (gdb_stdlog
,
2683 "infrun: clear_proceed_status_thread: thread %s "
2684 "has pending wait status %s "
2685 "(currently_stepping=%d).\n",
2686 target_pid_to_str (tp
->ptid
).c_str (),
2688 currently_stepping (tp
));
2692 /* If this signal should not be seen by program, give it zero.
2693 Used for debugging signals. */
2694 if (!signal_pass_state (tp
->suspend
.stop_signal
))
2695 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
2697 delete tp
->thread_fsm
;
2698 tp
->thread_fsm
= NULL
;
2700 tp
->control
.trap_expected
= 0;
2701 tp
->control
.step_range_start
= 0;
2702 tp
->control
.step_range_end
= 0;
2703 tp
->control
.may_range_step
= 0;
2704 tp
->control
.step_frame_id
= null_frame_id
;
2705 tp
->control
.step_stack_frame_id
= null_frame_id
;
2706 tp
->control
.step_over_calls
= STEP_OVER_UNDEBUGGABLE
;
2707 tp
->control
.step_start_function
= NULL
;
2708 tp
->stop_requested
= 0;
2710 tp
->control
.stop_step
= 0;
2712 tp
->control
.proceed_to_finish
= 0;
2714 tp
->control
.stepping_command
= 0;
2716 /* Discard any remaining commands or status from previous stop. */
2717 bpstat_clear (&tp
->control
.stop_bpstat
);
2721 clear_proceed_status (int step
)
2723 /* With scheduler-locking replay, stop replaying other threads if we're
2724 not replaying the user-visible resume ptid.
2726 This is a convenience feature to not require the user to explicitly
2727 stop replaying the other threads. We're assuming that the user's
2728 intent is to resume tracing the recorded process. */
2729 if (!non_stop
&& scheduler_mode
== schedlock_replay
2730 && target_record_is_replaying (minus_one_ptid
)
2731 && !target_record_will_replay (user_visible_resume_ptid (step
),
2732 execution_direction
))
2733 target_record_stop_replaying ();
2735 if (!non_stop
&& inferior_ptid
!= null_ptid
)
2737 ptid_t resume_ptid
= user_visible_resume_ptid (step
);
2739 /* In all-stop mode, delete the per-thread status of all threads
2740 we're about to resume, implicitly and explicitly. */
2741 for (thread_info
*tp
: all_non_exited_threads (resume_ptid
))
2742 clear_proceed_status_thread (tp
);
2745 if (inferior_ptid
!= null_ptid
)
2747 struct inferior
*inferior
;
2751 /* If in non-stop mode, only delete the per-thread status of
2752 the current thread. */
2753 clear_proceed_status_thread (inferior_thread ());
2756 inferior
= current_inferior ();
2757 inferior
->control
.stop_soon
= NO_STOP_QUIETLY
;
2760 gdb::observers::about_to_proceed
.notify ();
2763 /* Returns true if TP is still stopped at a breakpoint that needs
2764 stepping-over in order to make progress. If the breakpoint is gone
2765 meanwhile, we can skip the whole step-over dance. */
2768 thread_still_needs_step_over_bp (struct thread_info
*tp
)
2770 if (tp
->stepping_over_breakpoint
)
2772 struct regcache
*regcache
= get_thread_regcache (tp
);
2774 if (breakpoint_here_p (regcache
->aspace (),
2775 regcache_read_pc (regcache
))
2776 == ordinary_breakpoint_here
)
2779 tp
->stepping_over_breakpoint
= 0;
2785 /* Check whether thread TP still needs to start a step-over in order
2786 to make progress when resumed. Returns an bitwise or of enum
2787 step_over_what bits, indicating what needs to be stepped over. */
2789 static step_over_what
2790 thread_still_needs_step_over (struct thread_info
*tp
)
2792 step_over_what what
= 0;
2794 if (thread_still_needs_step_over_bp (tp
))
2795 what
|= STEP_OVER_BREAKPOINT
;
2797 if (tp
->stepping_over_watchpoint
2798 && !target_have_steppable_watchpoint
)
2799 what
|= STEP_OVER_WATCHPOINT
;
2804 /* Returns true if scheduler locking applies. STEP indicates whether
2805 we're about to do a step/next-like command to a thread. */
2808 schedlock_applies (struct thread_info
*tp
)
2810 return (scheduler_mode
== schedlock_on
2811 || (scheduler_mode
== schedlock_step
2812 && tp
->control
.stepping_command
)
2813 || (scheduler_mode
== schedlock_replay
2814 && target_record_will_replay (minus_one_ptid
,
2815 execution_direction
)));
2818 /* Basic routine for continuing the program in various fashions.
2820 ADDR is the address to resume at, or -1 for resume where stopped.
2821 SIGGNAL is the signal to give it, or GDB_SIGNAL_0 for none,
2822 or GDB_SIGNAL_DEFAULT for act according to how it stopped.
2824 You should call clear_proceed_status before calling proceed. */
2827 proceed (CORE_ADDR addr
, enum gdb_signal siggnal
)
2829 struct regcache
*regcache
;
2830 struct gdbarch
*gdbarch
;
2833 struct execution_control_state ecss
;
2834 struct execution_control_state
*ecs
= &ecss
;
2837 /* If we're stopped at a fork/vfork, follow the branch set by the
2838 "set follow-fork-mode" command; otherwise, we'll just proceed
2839 resuming the current thread. */
2840 if (!follow_fork ())
2842 /* The target for some reason decided not to resume. */
2844 if (target_can_async_p ())
2845 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
2849 /* We'll update this if & when we switch to a new thread. */
2850 previous_inferior_ptid
= inferior_ptid
;
2852 regcache
= get_current_regcache ();
2853 gdbarch
= regcache
->arch ();
2854 const address_space
*aspace
= regcache
->aspace ();
2856 pc
= regcache_read_pc (regcache
);
2857 thread_info
*cur_thr
= inferior_thread ();
2859 /* Fill in with reasonable starting values. */
2860 init_thread_stepping_state (cur_thr
);
2862 gdb_assert (!thread_is_in_step_over_chain (cur_thr
));
2864 if (addr
== (CORE_ADDR
) -1)
2866 if (pc
== cur_thr
->suspend
.stop_pc
2867 && breakpoint_here_p (aspace
, pc
) == ordinary_breakpoint_here
2868 && execution_direction
!= EXEC_REVERSE
)
2869 /* There is a breakpoint at the address we will resume at,
2870 step one instruction before inserting breakpoints so that
2871 we do not stop right away (and report a second hit at this
2874 Note, we don't do this in reverse, because we won't
2875 actually be executing the breakpoint insn anyway.
2876 We'll be (un-)executing the previous instruction. */
2877 cur_thr
->stepping_over_breakpoint
= 1;
2878 else if (gdbarch_single_step_through_delay_p (gdbarch
)
2879 && gdbarch_single_step_through_delay (gdbarch
,
2880 get_current_frame ()))
2881 /* We stepped onto an instruction that needs to be stepped
2882 again before re-inserting the breakpoint, do so. */
2883 cur_thr
->stepping_over_breakpoint
= 1;
2887 regcache_write_pc (regcache
, addr
);
2890 if (siggnal
!= GDB_SIGNAL_DEFAULT
)
2891 cur_thr
->suspend
.stop_signal
= siggnal
;
2893 resume_ptid
= user_visible_resume_ptid (cur_thr
->control
.stepping_command
);
2895 /* If an exception is thrown from this point on, make sure to
2896 propagate GDB's knowledge of the executing state to the
2897 frontend/user running state. */
2898 scoped_finish_thread_state
finish_state (resume_ptid
);
2900 /* Even if RESUME_PTID is a wildcard, and we end up resuming fewer
2901 threads (e.g., we might need to set threads stepping over
2902 breakpoints first), from the user/frontend's point of view, all
2903 threads in RESUME_PTID are now running. Unless we're calling an
2904 inferior function, as in that case we pretend the inferior
2905 doesn't run at all. */
2906 if (!cur_thr
->control
.in_infcall
)
2907 set_running (resume_ptid
, 1);
2910 fprintf_unfiltered (gdb_stdlog
,
2911 "infrun: proceed (addr=%s, signal=%s)\n",
2912 paddress (gdbarch
, addr
),
2913 gdb_signal_to_symbol_string (siggnal
));
2915 annotate_starting ();
2917 /* Make sure that output from GDB appears before output from the
2919 gdb_flush (gdb_stdout
);
2921 /* Since we've marked the inferior running, give it the terminal. A
2922 QUIT/Ctrl-C from here on is forwarded to the target (which can
2923 still detect attempts to unblock a stuck connection with repeated
2924 Ctrl-C from within target_pass_ctrlc). */
2925 target_terminal::inferior ();
2927 /* In a multi-threaded task we may select another thread and
2928 then continue or step.
2930 But if a thread that we're resuming had stopped at a breakpoint,
2931 it will immediately cause another breakpoint stop without any
2932 execution (i.e. it will report a breakpoint hit incorrectly). So
2933 we must step over it first.
2935 Look for threads other than the current (TP) that reported a
2936 breakpoint hit and haven't been resumed yet since. */
2938 /* If scheduler locking applies, we can avoid iterating over all
2940 if (!non_stop
&& !schedlock_applies (cur_thr
))
2942 for (thread_info
*tp
: all_non_exited_threads (resume_ptid
))
2944 /* Ignore the current thread here. It's handled
2949 if (!thread_still_needs_step_over (tp
))
2952 gdb_assert (!thread_is_in_step_over_chain (tp
));
2955 fprintf_unfiltered (gdb_stdlog
,
2956 "infrun: need to step-over [%s] first\n",
2957 target_pid_to_str (tp
->ptid
).c_str ());
2959 thread_step_over_chain_enqueue (tp
);
2963 /* Enqueue the current thread last, so that we move all other
2964 threads over their breakpoints first. */
2965 if (cur_thr
->stepping_over_breakpoint
)
2966 thread_step_over_chain_enqueue (cur_thr
);
2968 /* If the thread isn't started, we'll still need to set its prev_pc,
2969 so that switch_back_to_stepped_thread knows the thread hasn't
2970 advanced. Must do this before resuming any thread, as in
2971 all-stop/remote, once we resume we can't send any other packet
2972 until the target stops again. */
2973 cur_thr
->prev_pc
= regcache_read_pc (regcache
);
2976 scoped_restore save_defer_tc
= make_scoped_defer_target_commit_resume ();
2978 started
= start_step_over ();
2980 if (step_over_info_valid_p ())
2982 /* Either this thread started a new in-line step over, or some
2983 other thread was already doing one. In either case, don't
2984 resume anything else until the step-over is finished. */
2986 else if (started
&& !target_is_non_stop_p ())
2988 /* A new displaced stepping sequence was started. In all-stop,
2989 we can't talk to the target anymore until it next stops. */
2991 else if (!non_stop
&& target_is_non_stop_p ())
2993 /* In all-stop, but the target is always in non-stop mode.
2994 Start all other threads that are implicitly resumed too. */
2995 for (thread_info
*tp
: all_non_exited_threads (resume_ptid
))
3000 fprintf_unfiltered (gdb_stdlog
,
3001 "infrun: proceed: [%s] resumed\n",
3002 target_pid_to_str (tp
->ptid
).c_str ());
3003 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
3007 if (thread_is_in_step_over_chain (tp
))
3010 fprintf_unfiltered (gdb_stdlog
,
3011 "infrun: proceed: [%s] needs step-over\n",
3012 target_pid_to_str (tp
->ptid
).c_str ());
3017 fprintf_unfiltered (gdb_stdlog
,
3018 "infrun: proceed: resuming %s\n",
3019 target_pid_to_str (tp
->ptid
).c_str ());
3021 reset_ecs (ecs
, tp
);
3022 switch_to_thread (tp
);
3023 keep_going_pass_signal (ecs
);
3024 if (!ecs
->wait_some_more
)
3025 error (_("Command aborted."));
3028 else if (!cur_thr
->resumed
&& !thread_is_in_step_over_chain (cur_thr
))
3030 /* The thread wasn't started, and isn't queued, run it now. */
3031 reset_ecs (ecs
, cur_thr
);
3032 switch_to_thread (cur_thr
);
3033 keep_going_pass_signal (ecs
);
3034 if (!ecs
->wait_some_more
)
3035 error (_("Command aborted."));
3039 target_commit_resume ();
3041 finish_state
.release ();
3043 /* Tell the event loop to wait for it to stop. If the target
3044 supports asynchronous execution, it'll do this from within
3046 if (!target_can_async_p ())
3047 mark_async_event_handler (infrun_async_inferior_event_token
);
3051 /* Start remote-debugging of a machine over a serial link. */
3054 start_remote (int from_tty
)
3056 struct inferior
*inferior
;
3058 inferior
= current_inferior ();
3059 inferior
->control
.stop_soon
= STOP_QUIETLY_REMOTE
;
3061 /* Always go on waiting for the target, regardless of the mode. */
3062 /* FIXME: cagney/1999-09-23: At present it isn't possible to
3063 indicate to wait_for_inferior that a target should timeout if
3064 nothing is returned (instead of just blocking). Because of this,
3065 targets expecting an immediate response need to, internally, set
3066 things up so that the target_wait() is forced to eventually
3068 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
3069 differentiate to its caller what the state of the target is after
3070 the initial open has been performed. Here we're assuming that
3071 the target has stopped. It should be possible to eventually have
3072 target_open() return to the caller an indication that the target
3073 is currently running and GDB state should be set to the same as
3074 for an async run. */
3075 wait_for_inferior ();
3077 /* Now that the inferior has stopped, do any bookkeeping like
3078 loading shared libraries. We want to do this before normal_stop,
3079 so that the displayed frame is up to date. */
3080 post_create_inferior (current_top_target (), from_tty
);
3085 /* Initialize static vars when a new inferior begins. */
3088 init_wait_for_inferior (void)
3090 /* These are meaningless until the first time through wait_for_inferior. */
3092 breakpoint_init_inferior (inf_starting
);
3094 clear_proceed_status (0);
3096 target_last_wait_ptid
= minus_one_ptid
;
3098 previous_inferior_ptid
= inferior_ptid
;
3103 static void handle_inferior_event (struct execution_control_state
*ecs
);
3105 static void handle_step_into_function (struct gdbarch
*gdbarch
,
3106 struct execution_control_state
*ecs
);
3107 static void handle_step_into_function_backward (struct gdbarch
*gdbarch
,
3108 struct execution_control_state
*ecs
);
3109 static void handle_signal_stop (struct execution_control_state
*ecs
);
3110 static void check_exception_resume (struct execution_control_state
*,
3111 struct frame_info
*);
3113 static void end_stepping_range (struct execution_control_state
*ecs
);
3114 static void stop_waiting (struct execution_control_state
*ecs
);
3115 static void keep_going (struct execution_control_state
*ecs
);
3116 static void process_event_stop_test (struct execution_control_state
*ecs
);
3117 static int switch_back_to_stepped_thread (struct execution_control_state
*ecs
);
3119 /* This function is attached as a "thread_stop_requested" observer.
3120 Cleanup local state that assumed the PTID was to be resumed, and
3121 report the stop to the frontend. */
3124 infrun_thread_stop_requested (ptid_t ptid
)
3126 /* PTID was requested to stop. If the thread was already stopped,
3127 but the user/frontend doesn't know about that yet (e.g., the
3128 thread had been temporarily paused for some step-over), set up
3129 for reporting the stop now. */
3130 for (thread_info
*tp
: all_threads (ptid
))
3132 if (tp
->state
!= THREAD_RUNNING
)
3137 /* Remove matching threads from the step-over queue, so
3138 start_step_over doesn't try to resume them
3140 if (thread_is_in_step_over_chain (tp
))
3141 thread_step_over_chain_remove (tp
);
3143 /* If the thread is stopped, but the user/frontend doesn't
3144 know about that yet, queue a pending event, as if the
3145 thread had just stopped now. Unless the thread already had
3147 if (!tp
->suspend
.waitstatus_pending_p
)
3149 tp
->suspend
.waitstatus_pending_p
= 1;
3150 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_STOPPED
;
3151 tp
->suspend
.waitstatus
.value
.sig
= GDB_SIGNAL_0
;
3154 /* Clear the inline-frame state, since we're re-processing the
3156 clear_inline_frame_state (tp
->ptid
);
3158 /* If this thread was paused because some other thread was
3159 doing an inline-step over, let that finish first. Once
3160 that happens, we'll restart all threads and consume pending
3161 stop events then. */
3162 if (step_over_info_valid_p ())
3165 /* Otherwise we can process the (new) pending event now. Set
3166 it so this pending event is considered by
3173 infrun_thread_thread_exit (struct thread_info
*tp
, int silent
)
3175 if (target_last_wait_ptid
== tp
->ptid
)
3176 nullify_last_target_wait_ptid ();
3179 /* Delete the step resume, single-step and longjmp/exception resume
3180 breakpoints of TP. */
3183 delete_thread_infrun_breakpoints (struct thread_info
*tp
)
3185 delete_step_resume_breakpoint (tp
);
3186 delete_exception_resume_breakpoint (tp
);
3187 delete_single_step_breakpoints (tp
);
3190 /* If the target still has execution, call FUNC for each thread that
3191 just stopped. In all-stop, that's all the non-exited threads; in
3192 non-stop, that's the current thread, only. */
3194 typedef void (*for_each_just_stopped_thread_callback_func
)
3195 (struct thread_info
*tp
);
3198 for_each_just_stopped_thread (for_each_just_stopped_thread_callback_func func
)
3200 if (!target_has_execution
|| inferior_ptid
== null_ptid
)
3203 if (target_is_non_stop_p ())
3205 /* If in non-stop mode, only the current thread stopped. */
3206 func (inferior_thread ());
3210 /* In all-stop mode, all threads have stopped. */
3211 for (thread_info
*tp
: all_non_exited_threads ())
3216 /* Delete the step resume and longjmp/exception resume breakpoints of
3217 the threads that just stopped. */
3220 delete_just_stopped_threads_infrun_breakpoints (void)
3222 for_each_just_stopped_thread (delete_thread_infrun_breakpoints
);
3225 /* Delete the single-step breakpoints of the threads that just
3229 delete_just_stopped_threads_single_step_breakpoints (void)
3231 for_each_just_stopped_thread (delete_single_step_breakpoints
);
3237 print_target_wait_results (ptid_t waiton_ptid
, ptid_t result_ptid
,
3238 const struct target_waitstatus
*ws
)
3240 std::string status_string
= target_waitstatus_to_string (ws
);
3243 /* The text is split over several lines because it was getting too long.
3244 Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
3245 output as a unit; we want only one timestamp printed if debug_timestamp
3248 stb
.printf ("infrun: target_wait (%d.%ld.%ld",
3251 waiton_ptid
.tid ());
3252 if (waiton_ptid
.pid () != -1)
3253 stb
.printf (" [%s]", target_pid_to_str (waiton_ptid
).c_str ());
3254 stb
.printf (", status) =\n");
3255 stb
.printf ("infrun: %d.%ld.%ld [%s],\n",
3259 target_pid_to_str (result_ptid
).c_str ());
3260 stb
.printf ("infrun: %s\n", status_string
.c_str ());
3262 /* This uses %s in part to handle %'s in the text, but also to avoid
3263 a gcc error: the format attribute requires a string literal. */
3264 fprintf_unfiltered (gdb_stdlog
, "%s", stb
.c_str ());
3267 /* Select a thread at random, out of those which are resumed and have
3270 static struct thread_info
*
3271 random_pending_event_thread (ptid_t waiton_ptid
)
3275 auto has_event
= [] (thread_info
*tp
)
3278 && tp
->suspend
.waitstatus_pending_p
);
3281 /* First see how many events we have. Count only resumed threads
3282 that have an event pending. */
3283 for (thread_info
*tp
: all_non_exited_threads (waiton_ptid
))
3287 if (num_events
== 0)
3290 /* Now randomly pick a thread out of those that have had events. */
3291 int random_selector
= (int) ((num_events
* (double) rand ())
3292 / (RAND_MAX
+ 1.0));
3294 if (debug_infrun
&& num_events
> 1)
3295 fprintf_unfiltered (gdb_stdlog
,
3296 "infrun: Found %d events, selecting #%d\n",
3297 num_events
, random_selector
);
3299 /* Select the Nth thread that has had an event. */
3300 for (thread_info
*tp
: all_non_exited_threads (waiton_ptid
))
3302 if (random_selector
-- == 0)
3305 gdb_assert_not_reached ("event thread not found");
3308 /* Wrapper for target_wait that first checks whether threads have
3309 pending statuses to report before actually asking the target for
3313 do_target_wait (ptid_t ptid
, struct target_waitstatus
*status
, int options
)
3316 struct thread_info
*tp
;
3318 /* First check if there is a resumed thread with a wait status
3320 if (ptid
== minus_one_ptid
|| ptid
.is_pid ())
3322 tp
= random_pending_event_thread (ptid
);
3327 fprintf_unfiltered (gdb_stdlog
,
3328 "infrun: Waiting for specific thread %s.\n",
3329 target_pid_to_str (ptid
).c_str ());
3331 /* We have a specific thread to check. */
3332 tp
= find_thread_ptid (ptid
);
3333 gdb_assert (tp
!= NULL
);
3334 if (!tp
->suspend
.waitstatus_pending_p
)
3339 && (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3340 || tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
3342 struct regcache
*regcache
= get_thread_regcache (tp
);
3343 struct gdbarch
*gdbarch
= regcache
->arch ();
3347 pc
= regcache_read_pc (regcache
);
3349 if (pc
!= tp
->suspend
.stop_pc
)
3352 fprintf_unfiltered (gdb_stdlog
,
3353 "infrun: PC of %s changed. was=%s, now=%s\n",
3354 target_pid_to_str (tp
->ptid
).c_str (),
3355 paddress (gdbarch
, tp
->suspend
.stop_pc
),
3356 paddress (gdbarch
, pc
));
3359 else if (!breakpoint_inserted_here_p (regcache
->aspace (), pc
))
3362 fprintf_unfiltered (gdb_stdlog
,
3363 "infrun: previous breakpoint of %s, at %s gone\n",
3364 target_pid_to_str (tp
->ptid
).c_str (),
3365 paddress (gdbarch
, pc
));
3373 fprintf_unfiltered (gdb_stdlog
,
3374 "infrun: pending event of %s cancelled.\n",
3375 target_pid_to_str (tp
->ptid
).c_str ());
3377 tp
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_SPURIOUS
;
3378 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3387 = target_waitstatus_to_string (&tp
->suspend
.waitstatus
);
3389 fprintf_unfiltered (gdb_stdlog
,
3390 "infrun: Using pending wait status %s for %s.\n",
3392 target_pid_to_str (tp
->ptid
).c_str ());
3395 /* Now that we've selected our final event LWP, un-adjust its PC
3396 if it was a software breakpoint (and the target doesn't
3397 always adjust the PC itself). */
3398 if (tp
->suspend
.stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3399 && !target_supports_stopped_by_sw_breakpoint ())
3401 struct regcache
*regcache
;
3402 struct gdbarch
*gdbarch
;
3405 regcache
= get_thread_regcache (tp
);
3406 gdbarch
= regcache
->arch ();
3408 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3413 pc
= regcache_read_pc (regcache
);
3414 regcache_write_pc (regcache
, pc
+ decr_pc
);
3418 tp
->suspend
.stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3419 *status
= tp
->suspend
.waitstatus
;
3420 tp
->suspend
.waitstatus_pending_p
= 0;
3422 /* Wake up the event loop again, until all pending events are
3424 if (target_is_async_p ())
3425 mark_async_event_handler (infrun_async_inferior_event_token
);
3429 /* But if we don't find one, we'll have to wait. */
3431 if (deprecated_target_wait_hook
)
3432 event_ptid
= deprecated_target_wait_hook (ptid
, status
, options
);
3434 event_ptid
= target_wait (ptid
, status
, options
);
3439 /* Prepare and stabilize the inferior for detaching it. E.g.,
3440 detaching while a thread is displaced stepping is a recipe for
3441 crashing it, as nothing would readjust the PC out of the scratch
3445 prepare_for_detach (void)
3447 struct inferior
*inf
= current_inferior ();
3448 ptid_t pid_ptid
= ptid_t (inf
->pid
);
3450 displaced_step_inferior_state
*displaced
= get_displaced_stepping_state (inf
);
3452 /* Is any thread of this process displaced stepping? If not,
3453 there's nothing else to do. */
3454 if (displaced
->step_thread
== nullptr)
3458 fprintf_unfiltered (gdb_stdlog
,
3459 "displaced-stepping in-process while detaching");
3461 scoped_restore restore_detaching
= make_scoped_restore (&inf
->detaching
, true);
3463 while (displaced
->step_thread
!= nullptr)
3465 struct execution_control_state ecss
;
3466 struct execution_control_state
*ecs
;
3469 memset (ecs
, 0, sizeof (*ecs
));
3471 overlay_cache_invalid
= 1;
3472 /* Flush target cache before starting to handle each event.
3473 Target was running and cache could be stale. This is just a
3474 heuristic. Running threads may modify target memory, but we
3475 don't get any event. */
3476 target_dcache_invalidate ();
3478 ecs
->ptid
= do_target_wait (pid_ptid
, &ecs
->ws
, 0);
3481 print_target_wait_results (pid_ptid
, ecs
->ptid
, &ecs
->ws
);
3483 /* If an error happens while handling the event, propagate GDB's
3484 knowledge of the executing state to the frontend/user running
3486 scoped_finish_thread_state
finish_state (minus_one_ptid
);
3488 /* Now figure out what to do with the result of the result. */
3489 handle_inferior_event (ecs
);
3491 /* No error, don't finish the state yet. */
3492 finish_state
.release ();
3494 /* Breakpoints and watchpoints are not installed on the target
3495 at this point, and signals are passed directly to the
3496 inferior, so this must mean the process is gone. */
3497 if (!ecs
->wait_some_more
)
3499 restore_detaching
.release ();
3500 error (_("Program exited while detaching"));
3504 restore_detaching
.release ();
3507 /* Wait for control to return from inferior to debugger.
3509 If inferior gets a signal, we may decide to start it up again
3510 instead of returning. That is why there is a loop in this function.
3511 When this function actually returns it means the inferior
3512 should be left stopped and GDB should read more commands. */
3515 wait_for_inferior (void)
3519 (gdb_stdlog
, "infrun: wait_for_inferior ()\n");
3521 SCOPE_EXIT
{ delete_just_stopped_threads_infrun_breakpoints (); };
3523 /* If an error happens while handling the event, propagate GDB's
3524 knowledge of the executing state to the frontend/user running
3526 scoped_finish_thread_state
finish_state (minus_one_ptid
);
3530 struct execution_control_state ecss
;
3531 struct execution_control_state
*ecs
= &ecss
;
3532 ptid_t waiton_ptid
= minus_one_ptid
;
3534 memset (ecs
, 0, sizeof (*ecs
));
3536 overlay_cache_invalid
= 1;
3538 /* Flush target cache before starting to handle each event.
3539 Target was running and cache could be stale. This is just a
3540 heuristic. Running threads may modify target memory, but we
3541 don't get any event. */
3542 target_dcache_invalidate ();
3544 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
, 0);
3547 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3549 /* Now figure out what to do with the result of the result. */
3550 handle_inferior_event (ecs
);
3552 if (!ecs
->wait_some_more
)
3556 /* No error, don't finish the state yet. */
3557 finish_state
.release ();
3560 /* Cleanup that reinstalls the readline callback handler, if the
3561 target is running in the background. If while handling the target
3562 event something triggered a secondary prompt, like e.g., a
3563 pagination prompt, we'll have removed the callback handler (see
3564 gdb_readline_wrapper_line). Need to do this as we go back to the
3565 event loop, ready to process further input. Note this has no
3566 effect if the handler hasn't actually been removed, because calling
3567 rl_callback_handler_install resets the line buffer, thus losing
3571 reinstall_readline_callback_handler_cleanup ()
3573 struct ui
*ui
= current_ui
;
3577 /* We're not going back to the top level event loop yet. Don't
3578 install the readline callback, as it'd prep the terminal,
3579 readline-style (raw, noecho) (e.g., --batch). We'll install
3580 it the next time the prompt is displayed, when we're ready
3585 if (ui
->command_editing
&& ui
->prompt_state
!= PROMPT_BLOCKED
)
3586 gdb_rl_callback_handler_reinstall ();
3589 /* Clean up the FSMs of threads that are now stopped. In non-stop,
3590 that's just the event thread. In all-stop, that's all threads. */
3593 clean_up_just_stopped_threads_fsms (struct execution_control_state
*ecs
)
3595 if (ecs
->event_thread
!= NULL
3596 && ecs
->event_thread
->thread_fsm
!= NULL
)
3597 ecs
->event_thread
->thread_fsm
->clean_up (ecs
->event_thread
);
3601 for (thread_info
*thr
: all_non_exited_threads ())
3603 if (thr
->thread_fsm
== NULL
)
3605 if (thr
== ecs
->event_thread
)
3608 switch_to_thread (thr
);
3609 thr
->thread_fsm
->clean_up (thr
);
3612 if (ecs
->event_thread
!= NULL
)
3613 switch_to_thread (ecs
->event_thread
);
3617 /* Helper for all_uis_check_sync_execution_done that works on the
3621 check_curr_ui_sync_execution_done (void)
3623 struct ui
*ui
= current_ui
;
3625 if (ui
->prompt_state
== PROMPT_NEEDED
3627 && !gdb_in_secondary_prompt_p (ui
))
3629 target_terminal::ours ();
3630 gdb::observers::sync_execution_done
.notify ();
3631 ui_register_input_event_handler (ui
);
3638 all_uis_check_sync_execution_done (void)
3640 SWITCH_THRU_ALL_UIS ()
3642 check_curr_ui_sync_execution_done ();
3649 all_uis_on_sync_execution_starting (void)
3651 SWITCH_THRU_ALL_UIS ()
3653 if (current_ui
->prompt_state
== PROMPT_NEEDED
)
3654 async_disable_stdin ();
3658 /* Asynchronous version of wait_for_inferior. It is called by the
3659 event loop whenever a change of state is detected on the file
3660 descriptor corresponding to the target. It can be called more than
3661 once to complete a single execution command. In such cases we need
3662 to keep the state in a global variable ECSS. If it is the last time
3663 that this function is called for a single execution command, then
3664 report to the user that the inferior has stopped, and do the
3665 necessary cleanups. */
3668 fetch_inferior_event (void *client_data
)
3670 struct execution_control_state ecss
;
3671 struct execution_control_state
*ecs
= &ecss
;
3673 ptid_t waiton_ptid
= minus_one_ptid
;
3675 memset (ecs
, 0, sizeof (*ecs
));
3677 /* Events are always processed with the main UI as current UI. This
3678 way, warnings, debug output, etc. are always consistently sent to
3679 the main console. */
3680 scoped_restore save_ui
= make_scoped_restore (¤t_ui
, main_ui
);
3682 /* End up with readline processing input, if necessary. */
3684 SCOPE_EXIT
{ reinstall_readline_callback_handler_cleanup (); };
3686 /* We're handling a live event, so make sure we're doing live
3687 debugging. If we're looking at traceframes while the target is
3688 running, we're going to need to get back to that mode after
3689 handling the event. */
3690 gdb::optional
<scoped_restore_current_traceframe
> maybe_restore_traceframe
;
3693 maybe_restore_traceframe
.emplace ();
3694 set_current_traceframe (-1);
3697 gdb::optional
<scoped_restore_current_thread
> maybe_restore_thread
;
3700 /* In non-stop mode, the user/frontend should not notice a thread
3701 switch due to internal events. Make sure we reverse to the
3702 user selected thread and frame after handling the event and
3703 running any breakpoint commands. */
3704 maybe_restore_thread
.emplace ();
3706 overlay_cache_invalid
= 1;
3707 /* Flush target cache before starting to handle each event. Target
3708 was running and cache could be stale. This is just a heuristic.
3709 Running threads may modify target memory, but we don't get any
3711 target_dcache_invalidate ();
3713 scoped_restore save_exec_dir
3714 = make_scoped_restore (&execution_direction
,
3715 target_execution_direction ());
3717 ecs
->ptid
= do_target_wait (waiton_ptid
, &ecs
->ws
,
3718 target_can_async_p () ? TARGET_WNOHANG
: 0);
3721 print_target_wait_results (waiton_ptid
, ecs
->ptid
, &ecs
->ws
);
3723 /* If an error happens while handling the event, propagate GDB's
3724 knowledge of the executing state to the frontend/user running
3726 ptid_t finish_ptid
= !target_is_non_stop_p () ? minus_one_ptid
: ecs
->ptid
;
3727 scoped_finish_thread_state
finish_state (finish_ptid
);
3729 /* Get executed before scoped_restore_current_thread above to apply
3730 still for the thread which has thrown the exception. */
3731 auto defer_bpstat_clear
3732 = make_scope_exit (bpstat_clear_actions
);
3733 auto defer_delete_threads
3734 = make_scope_exit (delete_just_stopped_threads_infrun_breakpoints
);
3736 /* Now figure out what to do with the result of the result. */
3737 handle_inferior_event (ecs
);
3739 if (!ecs
->wait_some_more
)
3741 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
3742 int should_stop
= 1;
3743 struct thread_info
*thr
= ecs
->event_thread
;
3745 delete_just_stopped_threads_infrun_breakpoints ();
3749 struct thread_fsm
*thread_fsm
= thr
->thread_fsm
;
3751 if (thread_fsm
!= NULL
)
3752 should_stop
= thread_fsm
->should_stop (thr
);
3761 bool should_notify_stop
= true;
3764 clean_up_just_stopped_threads_fsms (ecs
);
3766 if (thr
!= NULL
&& thr
->thread_fsm
!= NULL
)
3767 should_notify_stop
= thr
->thread_fsm
->should_notify_stop ();
3769 if (should_notify_stop
)
3771 /* We may not find an inferior if this was a process exit. */
3772 if (inf
== NULL
|| inf
->control
.stop_soon
== NO_STOP_QUIETLY
)
3773 proceeded
= normal_stop ();
3778 inferior_event_handler (INF_EXEC_COMPLETE
, NULL
);
3784 defer_delete_threads
.release ();
3785 defer_bpstat_clear
.release ();
3787 /* No error, don't finish the thread states yet. */
3788 finish_state
.release ();
3790 /* This scope is used to ensure that readline callbacks are
3791 reinstalled here. */
3794 /* If a UI was in sync execution mode, and now isn't, restore its
3795 prompt (a synchronous execution command has finished, and we're
3796 ready for input). */
3797 all_uis_check_sync_execution_done ();
3800 && exec_done_display_p
3801 && (inferior_ptid
== null_ptid
3802 || inferior_thread ()->state
!= THREAD_RUNNING
))
3803 printf_unfiltered (_("completed.\n"));
3806 /* Record the frame and location we're currently stepping through. */
3808 set_step_info (struct frame_info
*frame
, struct symtab_and_line sal
)
3810 struct thread_info
*tp
= inferior_thread ();
3812 tp
->control
.step_frame_id
= get_frame_id (frame
);
3813 tp
->control
.step_stack_frame_id
= get_stack_frame_id (frame
);
3815 tp
->current_symtab
= sal
.symtab
;
3816 tp
->current_line
= sal
.line
;
3819 /* Clear context switchable stepping state. */
3822 init_thread_stepping_state (struct thread_info
*tss
)
3824 tss
->stepped_breakpoint
= 0;
3825 tss
->stepping_over_breakpoint
= 0;
3826 tss
->stepping_over_watchpoint
= 0;
3827 tss
->step_after_step_resume_breakpoint
= 0;
3830 /* Set the cached copy of the last ptid/waitstatus. */
3833 set_last_target_status (ptid_t ptid
, struct target_waitstatus status
)
3835 target_last_wait_ptid
= ptid
;
3836 target_last_waitstatus
= status
;
3839 /* Return the cached copy of the last pid/waitstatus returned by
3840 target_wait()/deprecated_target_wait_hook(). The data is actually
3841 cached by handle_inferior_event(), which gets called immediately
3842 after target_wait()/deprecated_target_wait_hook(). */
3845 get_last_target_status (ptid_t
*ptidp
, struct target_waitstatus
*status
)
3847 *ptidp
= target_last_wait_ptid
;
3848 *status
= target_last_waitstatus
;
3852 nullify_last_target_wait_ptid (void)
3854 target_last_wait_ptid
= minus_one_ptid
;
3857 /* Switch thread contexts. */
3860 context_switch (execution_control_state
*ecs
)
3863 && ecs
->ptid
!= inferior_ptid
3864 && ecs
->event_thread
!= inferior_thread ())
3866 fprintf_unfiltered (gdb_stdlog
, "infrun: Switching context from %s ",
3867 target_pid_to_str (inferior_ptid
).c_str ());
3868 fprintf_unfiltered (gdb_stdlog
, "to %s\n",
3869 target_pid_to_str (ecs
->ptid
).c_str ());
3872 switch_to_thread (ecs
->event_thread
);
3875 /* If the target can't tell whether we've hit breakpoints
3876 (target_supports_stopped_by_sw_breakpoint), and we got a SIGTRAP,
3877 check whether that could have been caused by a breakpoint. If so,
3878 adjust the PC, per gdbarch_decr_pc_after_break. */
3881 adjust_pc_after_break (struct thread_info
*thread
,
3882 struct target_waitstatus
*ws
)
3884 struct regcache
*regcache
;
3885 struct gdbarch
*gdbarch
;
3886 CORE_ADDR breakpoint_pc
, decr_pc
;
3888 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
3889 we aren't, just return.
3891 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
3892 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
3893 implemented by software breakpoints should be handled through the normal
3896 NOTE drow/2004-01-31: On some targets, breakpoints may generate
3897 different signals (SIGILL or SIGEMT for instance), but it is less
3898 clear where the PC is pointing afterwards. It may not match
3899 gdbarch_decr_pc_after_break. I don't know any specific target that
3900 generates these signals at breakpoints (the code has been in GDB since at
3901 least 1992) so I can not guess how to handle them here.
3903 In earlier versions of GDB, a target with
3904 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
3905 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
3906 target with both of these set in GDB history, and it seems unlikely to be
3907 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
3909 if (ws
->kind
!= TARGET_WAITKIND_STOPPED
)
3912 if (ws
->value
.sig
!= GDB_SIGNAL_TRAP
)
3915 /* In reverse execution, when a breakpoint is hit, the instruction
3916 under it has already been de-executed. The reported PC always
3917 points at the breakpoint address, so adjusting it further would
3918 be wrong. E.g., consider this case on a decr_pc_after_break == 1
3921 B1 0x08000000 : INSN1
3922 B2 0x08000001 : INSN2
3924 PC -> 0x08000003 : INSN4
3926 Say you're stopped at 0x08000003 as above. Reverse continuing
3927 from that point should hit B2 as below. Reading the PC when the
3928 SIGTRAP is reported should read 0x08000001 and INSN2 should have
3929 been de-executed already.
3931 B1 0x08000000 : INSN1
3932 B2 PC -> 0x08000001 : INSN2
3936 We can't apply the same logic as for forward execution, because
3937 we would wrongly adjust the PC to 0x08000000, since there's a
3938 breakpoint at PC - 1. We'd then report a hit on B1, although
3939 INSN1 hadn't been de-executed yet. Doing nothing is the correct
3941 if (execution_direction
== EXEC_REVERSE
)
3944 /* If the target can tell whether the thread hit a SW breakpoint,
3945 trust it. Targets that can tell also adjust the PC
3947 if (target_supports_stopped_by_sw_breakpoint ())
3950 /* Note that relying on whether a breakpoint is planted in memory to
3951 determine this can fail. E.g,. the breakpoint could have been
3952 removed since. Or the thread could have been told to step an
3953 instruction the size of a breakpoint instruction, and only
3954 _after_ was a breakpoint inserted at its address. */
3956 /* If this target does not decrement the PC after breakpoints, then
3957 we have nothing to do. */
3958 regcache
= get_thread_regcache (thread
);
3959 gdbarch
= regcache
->arch ();
3961 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
3965 const address_space
*aspace
= regcache
->aspace ();
3967 /* Find the location where (if we've hit a breakpoint) the
3968 breakpoint would be. */
3969 breakpoint_pc
= regcache_read_pc (regcache
) - decr_pc
;
3971 /* If the target can't tell whether a software breakpoint triggered,
3972 fallback to figuring it out based on breakpoints we think were
3973 inserted in the target, and on whether the thread was stepped or
3976 /* Check whether there actually is a software breakpoint inserted at
3979 If in non-stop mode, a race condition is possible where we've
3980 removed a breakpoint, but stop events for that breakpoint were
3981 already queued and arrive later. To suppress those spurious
3982 SIGTRAPs, we keep a list of such breakpoint locations for a bit,
3983 and retire them after a number of stop events are reported. Note
3984 this is an heuristic and can thus get confused. The real fix is
3985 to get the "stopped by SW BP and needs adjustment" info out of
3986 the target/kernel (and thus never reach here; see above). */
3987 if (software_breakpoint_inserted_here_p (aspace
, breakpoint_pc
)
3988 || (target_is_non_stop_p ()
3989 && moribund_breakpoint_here_p (aspace
, breakpoint_pc
)))
3991 gdb::optional
<scoped_restore_tmpl
<int>> restore_operation_disable
;
3993 if (record_full_is_used ())
3994 restore_operation_disable
.emplace
3995 (record_full_gdb_operation_disable_set ());
3997 /* When using hardware single-step, a SIGTRAP is reported for both
3998 a completed single-step and a software breakpoint. Need to
3999 differentiate between the two, as the latter needs adjusting
4000 but the former does not.
4002 The SIGTRAP can be due to a completed hardware single-step only if
4003 - we didn't insert software single-step breakpoints
4004 - this thread is currently being stepped
4006 If any of these events did not occur, we must have stopped due
4007 to hitting a software breakpoint, and have to back up to the
4010 As a special case, we could have hardware single-stepped a
4011 software breakpoint. In this case (prev_pc == breakpoint_pc),
4012 we also need to back up to the breakpoint address. */
4014 if (thread_has_single_step_breakpoints_set (thread
)
4015 || !currently_stepping (thread
)
4016 || (thread
->stepped_breakpoint
4017 && thread
->prev_pc
== breakpoint_pc
))
4018 regcache_write_pc (regcache
, breakpoint_pc
);
4023 stepped_in_from (struct frame_info
*frame
, struct frame_id step_frame_id
)
4025 for (frame
= get_prev_frame (frame
);
4027 frame
= get_prev_frame (frame
))
4029 if (frame_id_eq (get_frame_id (frame
), step_frame_id
))
4031 if (get_frame_type (frame
) != INLINE_FRAME
)
4038 /* If the event thread has the stop requested flag set, pretend it
4039 stopped for a GDB_SIGNAL_0 (i.e., as if it stopped due to
4043 handle_stop_requested (struct execution_control_state
*ecs
)
4045 if (ecs
->event_thread
->stop_requested
)
4047 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
4048 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
4049 handle_signal_stop (ecs
);
4055 /* Auxiliary function that handles syscall entry/return events.
4056 It returns 1 if the inferior should keep going (and GDB
4057 should ignore the event), or 0 if the event deserves to be
4061 handle_syscall_event (struct execution_control_state
*ecs
)
4063 struct regcache
*regcache
;
4066 context_switch (ecs
);
4068 regcache
= get_thread_regcache (ecs
->event_thread
);
4069 syscall_number
= ecs
->ws
.value
.syscall_number
;
4070 ecs
->event_thread
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4072 if (catch_syscall_enabled () > 0
4073 && catching_syscall_number (syscall_number
) > 0)
4076 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
4079 ecs
->event_thread
->control
.stop_bpstat
4080 = bpstat_stop_status (regcache
->aspace (),
4081 ecs
->event_thread
->suspend
.stop_pc
,
4082 ecs
->event_thread
, &ecs
->ws
);
4084 if (handle_stop_requested (ecs
))
4087 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4089 /* Catchpoint hit. */
4094 if (handle_stop_requested (ecs
))
4097 /* If no catchpoint triggered for this, then keep going. */
4102 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4105 fill_in_stop_func (struct gdbarch
*gdbarch
,
4106 struct execution_control_state
*ecs
)
4108 if (!ecs
->stop_func_filled_in
)
4112 /* Don't care about return value; stop_func_start and stop_func_name
4113 will both be 0 if it doesn't work. */
4114 find_pc_partial_function (ecs
->event_thread
->suspend
.stop_pc
,
4115 &ecs
->stop_func_name
,
4116 &ecs
->stop_func_start
,
4117 &ecs
->stop_func_end
,
4120 /* The call to find_pc_partial_function, above, will set
4121 stop_func_start and stop_func_end to the start and end
4122 of the range containing the stop pc. If this range
4123 contains the entry pc for the block (which is always the
4124 case for contiguous blocks), advance stop_func_start past
4125 the function's start offset and entrypoint. Note that
4126 stop_func_start is NOT advanced when in a range of a
4127 non-contiguous block that does not contain the entry pc. */
4128 if (block
!= nullptr
4129 && ecs
->stop_func_start
<= BLOCK_ENTRY_PC (block
)
4130 && BLOCK_ENTRY_PC (block
) < ecs
->stop_func_end
)
4132 ecs
->stop_func_start
4133 += gdbarch_deprecated_function_start_offset (gdbarch
);
4135 if (gdbarch_skip_entrypoint_p (gdbarch
))
4136 ecs
->stop_func_start
4137 = gdbarch_skip_entrypoint (gdbarch
, ecs
->stop_func_start
);
4140 ecs
->stop_func_filled_in
= 1;
4145 /* Return the STOP_SOON field of the inferior pointed at by ECS. */
4147 static enum stop_kind
4148 get_inferior_stop_soon (execution_control_state
*ecs
)
4150 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
4152 gdb_assert (inf
!= NULL
);
4153 return inf
->control
.stop_soon
;
4156 /* Wait for one event. Store the resulting waitstatus in WS, and
4157 return the event ptid. */
4160 wait_one (struct target_waitstatus
*ws
)
4163 ptid_t wait_ptid
= minus_one_ptid
;
4165 overlay_cache_invalid
= 1;
4167 /* Flush target cache before starting to handle each event.
4168 Target was running and cache could be stale. This is just a
4169 heuristic. Running threads may modify target memory, but we
4170 don't get any event. */
4171 target_dcache_invalidate ();
4173 if (deprecated_target_wait_hook
)
4174 event_ptid
= deprecated_target_wait_hook (wait_ptid
, ws
, 0);
4176 event_ptid
= target_wait (wait_ptid
, ws
, 0);
4179 print_target_wait_results (wait_ptid
, event_ptid
, ws
);
4184 /* Generate a wrapper for target_stopped_by_REASON that works on PTID
4185 instead of the current thread. */
4186 #define THREAD_STOPPED_BY(REASON) \
4188 thread_stopped_by_ ## REASON (ptid_t ptid) \
4190 scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid); \
4191 inferior_ptid = ptid; \
4193 return target_stopped_by_ ## REASON (); \
4196 /* Generate thread_stopped_by_watchpoint. */
4197 THREAD_STOPPED_BY (watchpoint
)
4198 /* Generate thread_stopped_by_sw_breakpoint. */
4199 THREAD_STOPPED_BY (sw_breakpoint
)
4200 /* Generate thread_stopped_by_hw_breakpoint. */
4201 THREAD_STOPPED_BY (hw_breakpoint
)
4203 /* Save the thread's event and stop reason to process it later. */
4206 save_waitstatus (struct thread_info
*tp
, struct target_waitstatus
*ws
)
4210 std::string statstr
= target_waitstatus_to_string (ws
);
4212 fprintf_unfiltered (gdb_stdlog
,
4213 "infrun: saving status %s for %d.%ld.%ld\n",
4220 /* Record for later. */
4221 tp
->suspend
.waitstatus
= *ws
;
4222 tp
->suspend
.waitstatus_pending_p
= 1;
4224 struct regcache
*regcache
= get_thread_regcache (tp
);
4225 const address_space
*aspace
= regcache
->aspace ();
4227 if (ws
->kind
== TARGET_WAITKIND_STOPPED
4228 && ws
->value
.sig
== GDB_SIGNAL_TRAP
)
4230 CORE_ADDR pc
= regcache_read_pc (regcache
);
4232 adjust_pc_after_break (tp
, &tp
->suspend
.waitstatus
);
4234 if (thread_stopped_by_watchpoint (tp
->ptid
))
4236 tp
->suspend
.stop_reason
4237 = TARGET_STOPPED_BY_WATCHPOINT
;
4239 else if (target_supports_stopped_by_sw_breakpoint ()
4240 && thread_stopped_by_sw_breakpoint (tp
->ptid
))
4242 tp
->suspend
.stop_reason
4243 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4245 else if (target_supports_stopped_by_hw_breakpoint ()
4246 && thread_stopped_by_hw_breakpoint (tp
->ptid
))
4248 tp
->suspend
.stop_reason
4249 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4251 else if (!target_supports_stopped_by_hw_breakpoint ()
4252 && hardware_breakpoint_inserted_here_p (aspace
,
4255 tp
->suspend
.stop_reason
4256 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4258 else if (!target_supports_stopped_by_sw_breakpoint ()
4259 && software_breakpoint_inserted_here_p (aspace
,
4262 tp
->suspend
.stop_reason
4263 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4265 else if (!thread_has_single_step_breakpoints_set (tp
)
4266 && currently_stepping (tp
))
4268 tp
->suspend
.stop_reason
4269 = TARGET_STOPPED_BY_SINGLE_STEP
;
4277 stop_all_threads (void)
4279 /* We may need multiple passes to discover all threads. */
4283 gdb_assert (target_is_non_stop_p ());
4286 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads\n");
4288 scoped_restore_current_thread restore_thread
;
4290 target_thread_events (1);
4291 SCOPE_EXIT
{ target_thread_events (0); };
4293 /* Request threads to stop, and then wait for the stops. Because
4294 threads we already know about can spawn more threads while we're
4295 trying to stop them, and we only learn about new threads when we
4296 update the thread list, do this in a loop, and keep iterating
4297 until two passes find no threads that need to be stopped. */
4298 for (pass
= 0; pass
< 2; pass
++, iterations
++)
4301 fprintf_unfiltered (gdb_stdlog
,
4302 "infrun: stop_all_threads, pass=%d, "
4303 "iterations=%d\n", pass
, iterations
);
4307 struct target_waitstatus ws
;
4310 update_thread_list ();
4312 /* Go through all threads looking for threads that we need
4313 to tell the target to stop. */
4314 for (thread_info
*t
: all_non_exited_threads ())
4318 /* If already stopping, don't request a stop again.
4319 We just haven't seen the notification yet. */
4320 if (!t
->stop_requested
)
4323 fprintf_unfiltered (gdb_stdlog
,
4324 "infrun: %s executing, "
4326 target_pid_to_str (t
->ptid
).c_str ());
4327 target_stop (t
->ptid
);
4328 t
->stop_requested
= 1;
4333 fprintf_unfiltered (gdb_stdlog
,
4334 "infrun: %s executing, "
4335 "already stopping\n",
4336 target_pid_to_str (t
->ptid
).c_str ());
4339 if (t
->stop_requested
)
4345 fprintf_unfiltered (gdb_stdlog
,
4346 "infrun: %s not executing\n",
4347 target_pid_to_str (t
->ptid
).c_str ());
4349 /* The thread may be not executing, but still be
4350 resumed with a pending status to process. */
4358 /* If we find new threads on the second iteration, restart
4359 over. We want to see two iterations in a row with all
4364 event_ptid
= wait_one (&ws
);
4367 fprintf_unfiltered (gdb_stdlog
,
4368 "infrun: stop_all_threads %s %s\n",
4369 target_waitstatus_to_string (&ws
).c_str (),
4370 target_pid_to_str (event_ptid
).c_str ());
4373 if (ws
.kind
== TARGET_WAITKIND_NO_RESUMED
4374 || ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
4375 || ws
.kind
== TARGET_WAITKIND_EXITED
4376 || ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
4378 /* All resumed threads exited
4379 or one thread/process exited/signalled. */
4383 thread_info
*t
= find_thread_ptid (event_ptid
);
4385 t
= add_thread (event_ptid
);
4387 t
->stop_requested
= 0;
4390 t
->control
.may_range_step
= 0;
4392 /* This may be the first time we see the inferior report
4394 inferior
*inf
= find_inferior_ptid (event_ptid
);
4395 if (inf
->needs_setup
)
4397 switch_to_thread_no_regs (t
);
4401 if (ws
.kind
== TARGET_WAITKIND_STOPPED
4402 && ws
.value
.sig
== GDB_SIGNAL_0
)
4404 /* We caught the event that we intended to catch, so
4405 there's no event pending. */
4406 t
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
4407 t
->suspend
.waitstatus_pending_p
= 0;
4409 if (displaced_step_fixup (t
, GDB_SIGNAL_0
) < 0)
4411 /* Add it back to the step-over queue. */
4414 fprintf_unfiltered (gdb_stdlog
,
4415 "infrun: displaced-step of %s "
4416 "canceled: adding back to the "
4417 "step-over queue\n",
4418 target_pid_to_str (t
->ptid
).c_str ());
4420 t
->control
.trap_expected
= 0;
4421 thread_step_over_chain_enqueue (t
);
4426 enum gdb_signal sig
;
4427 struct regcache
*regcache
;
4431 std::string statstr
= target_waitstatus_to_string (&ws
);
4433 fprintf_unfiltered (gdb_stdlog
,
4434 "infrun: target_wait %s, saving "
4435 "status for %d.%ld.%ld\n",
4442 /* Record for later. */
4443 save_waitstatus (t
, &ws
);
4445 sig
= (ws
.kind
== TARGET_WAITKIND_STOPPED
4446 ? ws
.value
.sig
: GDB_SIGNAL_0
);
4448 if (displaced_step_fixup (t
, sig
) < 0)
4450 /* Add it back to the step-over queue. */
4451 t
->control
.trap_expected
= 0;
4452 thread_step_over_chain_enqueue (t
);
4455 regcache
= get_thread_regcache (t
);
4456 t
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4460 fprintf_unfiltered (gdb_stdlog
,
4461 "infrun: saved stop_pc=%s for %s "
4462 "(currently_stepping=%d)\n",
4463 paddress (target_gdbarch (),
4464 t
->suspend
.stop_pc
),
4465 target_pid_to_str (t
->ptid
).c_str (),
4466 currently_stepping (t
));
4474 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads done\n");
4477 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
4480 handle_no_resumed (struct execution_control_state
*ecs
)
4482 if (target_can_async_p ())
4489 if (ui
->prompt_state
== PROMPT_BLOCKED
)
4497 /* There were no unwaited-for children left in the target, but,
4498 we're not synchronously waiting for events either. Just
4502 fprintf_unfiltered (gdb_stdlog
,
4503 "infrun: TARGET_WAITKIND_NO_RESUMED "
4504 "(ignoring: bg)\n");
4505 prepare_to_wait (ecs
);
4510 /* Otherwise, if we were running a synchronous execution command, we
4511 may need to cancel it and give the user back the terminal.
4513 In non-stop mode, the target can't tell whether we've already
4514 consumed previous stop events, so it can end up sending us a
4515 no-resumed event like so:
4517 #0 - thread 1 is left stopped
4519 #1 - thread 2 is resumed and hits breakpoint
4520 -> TARGET_WAITKIND_STOPPED
4522 #2 - thread 3 is resumed and exits
4523 this is the last resumed thread, so
4524 -> TARGET_WAITKIND_NO_RESUMED
4526 #3 - gdb processes stop for thread 2 and decides to re-resume
4529 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
4530 thread 2 is now resumed, so the event should be ignored.
4532 IOW, if the stop for thread 2 doesn't end a foreground command,
4533 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
4534 event. But it could be that the event meant that thread 2 itself
4535 (or whatever other thread was the last resumed thread) exited.
4537 To address this we refresh the thread list and check whether we
4538 have resumed threads _now_. In the example above, this removes
4539 thread 3 from the thread list. If thread 2 was re-resumed, we
4540 ignore this event. If we find no thread resumed, then we cancel
4541 the synchronous command show "no unwaited-for " to the user. */
4542 update_thread_list ();
4544 for (thread_info
*thread
: all_non_exited_threads ())
4546 if (thread
->executing
4547 || thread
->suspend
.waitstatus_pending_p
)
4549 /* There were no unwaited-for children left in the target at
4550 some point, but there are now. Just ignore. */
4552 fprintf_unfiltered (gdb_stdlog
,
4553 "infrun: TARGET_WAITKIND_NO_RESUMED "
4554 "(ignoring: found resumed)\n");
4555 prepare_to_wait (ecs
);
4560 /* Note however that we may find no resumed thread because the whole
4561 process exited meanwhile (thus updating the thread list results
4562 in an empty thread list). In this case we know we'll be getting
4563 a process exit event shortly. */
4564 for (inferior
*inf
: all_inferiors ())
4569 thread_info
*thread
= any_live_thread_of_inferior (inf
);
4573 fprintf_unfiltered (gdb_stdlog
,
4574 "infrun: TARGET_WAITKIND_NO_RESUMED "
4575 "(expect process exit)\n");
4576 prepare_to_wait (ecs
);
4581 /* Go ahead and report the event. */
4585 /* Given an execution control state that has been freshly filled in by
4586 an event from the inferior, figure out what it means and take
4589 The alternatives are:
4591 1) stop_waiting and return; to really stop and return to the
4594 2) keep_going and return; to wait for the next event (set
4595 ecs->event_thread->stepping_over_breakpoint to 1 to single step
4599 handle_inferior_event (struct execution_control_state
*ecs
)
4601 /* Make sure that all temporary struct value objects that were
4602 created during the handling of the event get deleted at the
4604 scoped_value_mark free_values
;
4606 enum stop_kind stop_soon
;
4609 fprintf_unfiltered (gdb_stdlog
, "infrun: handle_inferior_event %s\n",
4610 target_waitstatus_to_string (&ecs
->ws
).c_str ());
4612 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
4614 /* We had an event in the inferior, but we are not interested in
4615 handling it at this level. The lower layers have already
4616 done what needs to be done, if anything.
4618 One of the possible circumstances for this is when the
4619 inferior produces output for the console. The inferior has
4620 not stopped, and we are ignoring the event. Another possible
4621 circumstance is any event which the lower level knows will be
4622 reported multiple times without an intervening resume. */
4623 prepare_to_wait (ecs
);
4627 if (ecs
->ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
)
4629 prepare_to_wait (ecs
);
4633 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
4634 && handle_no_resumed (ecs
))
4637 /* Cache the last pid/waitstatus. */
4638 set_last_target_status (ecs
->ptid
, ecs
->ws
);
4640 /* Always clear state belonging to the previous time we stopped. */
4641 stop_stack_dummy
= STOP_NONE
;
4643 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4645 /* No unwaited-for children left. IOW, all resumed children
4647 stop_print_frame
= 0;
4652 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
4653 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
4655 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
4656 /* If it's a new thread, add it to the thread database. */
4657 if (ecs
->event_thread
== NULL
)
4658 ecs
->event_thread
= add_thread (ecs
->ptid
);
4660 /* Disable range stepping. If the next step request could use a
4661 range, this will be end up re-enabled then. */
4662 ecs
->event_thread
->control
.may_range_step
= 0;
4665 /* Dependent on valid ECS->EVENT_THREAD. */
4666 adjust_pc_after_break (ecs
->event_thread
, &ecs
->ws
);
4668 /* Dependent on the current PC value modified by adjust_pc_after_break. */
4669 reinit_frame_cache ();
4671 breakpoint_retire_moribund ();
4673 /* First, distinguish signals caused by the debugger from signals
4674 that have to do with the program's own actions. Note that
4675 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
4676 on the operating system version. Here we detect when a SIGILL or
4677 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
4678 something similar for SIGSEGV, since a SIGSEGV will be generated
4679 when we're trying to execute a breakpoint instruction on a
4680 non-executable stack. This happens for call dummy breakpoints
4681 for architectures like SPARC that place call dummies on the
4683 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
4684 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
4685 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
4686 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
4688 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
4690 if (breakpoint_inserted_here_p (regcache
->aspace (),
4691 regcache_read_pc (regcache
)))
4694 fprintf_unfiltered (gdb_stdlog
,
4695 "infrun: Treating signal as SIGTRAP\n");
4696 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
4700 /* Mark the non-executing threads accordingly. In all-stop, all
4701 threads of all processes are stopped when we get any event
4702 reported. In non-stop mode, only the event thread stops. */
4706 if (!target_is_non_stop_p ())
4707 mark_ptid
= minus_one_ptid
;
4708 else if (ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
4709 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4711 /* If we're handling a process exit in non-stop mode, even
4712 though threads haven't been deleted yet, one would think
4713 that there is nothing to do, as threads of the dead process
4714 will be soon deleted, and threads of any other process were
4715 left running. However, on some targets, threads survive a
4716 process exit event. E.g., for the "checkpoint" command,
4717 when the current checkpoint/fork exits, linux-fork.c
4718 automatically switches to another fork from within
4719 target_mourn_inferior, by associating the same
4720 inferior/thread to another fork. We haven't mourned yet at
4721 this point, but we must mark any threads left in the
4722 process as not-executing so that finish_thread_state marks
4723 them stopped (in the user's perspective) if/when we present
4724 the stop to the user. */
4725 mark_ptid
= ptid_t (ecs
->ptid
.pid ());
4728 mark_ptid
= ecs
->ptid
;
4730 set_executing (mark_ptid
, 0);
4732 /* Likewise the resumed flag. */
4733 set_resumed (mark_ptid
, 0);
4736 switch (ecs
->ws
.kind
)
4738 case TARGET_WAITKIND_LOADED
:
4739 context_switch (ecs
);
4740 /* Ignore gracefully during startup of the inferior, as it might
4741 be the shell which has just loaded some objects, otherwise
4742 add the symbols for the newly loaded objects. Also ignore at
4743 the beginning of an attach or remote session; we will query
4744 the full list of libraries once the connection is
4747 stop_soon
= get_inferior_stop_soon (ecs
);
4748 if (stop_soon
== NO_STOP_QUIETLY
)
4750 struct regcache
*regcache
;
4752 regcache
= get_thread_regcache (ecs
->event_thread
);
4754 handle_solib_event ();
4756 ecs
->event_thread
->control
.stop_bpstat
4757 = bpstat_stop_status (regcache
->aspace (),
4758 ecs
->event_thread
->suspend
.stop_pc
,
4759 ecs
->event_thread
, &ecs
->ws
);
4761 if (handle_stop_requested (ecs
))
4764 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4766 /* A catchpoint triggered. */
4767 process_event_stop_test (ecs
);
4771 /* If requested, stop when the dynamic linker notifies
4772 gdb of events. This allows the user to get control
4773 and place breakpoints in initializer routines for
4774 dynamically loaded objects (among other things). */
4775 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4776 if (stop_on_solib_events
)
4778 /* Make sure we print "Stopped due to solib-event" in
4780 stop_print_frame
= 1;
4787 /* If we are skipping through a shell, or through shared library
4788 loading that we aren't interested in, resume the program. If
4789 we're running the program normally, also resume. */
4790 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
4792 /* Loading of shared libraries might have changed breakpoint
4793 addresses. Make sure new breakpoints are inserted. */
4794 if (stop_soon
== NO_STOP_QUIETLY
)
4795 insert_breakpoints ();
4796 resume (GDB_SIGNAL_0
);
4797 prepare_to_wait (ecs
);
4801 /* But stop if we're attaching or setting up a remote
4803 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4804 || stop_soon
== STOP_QUIETLY_REMOTE
)
4807 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
4812 internal_error (__FILE__
, __LINE__
,
4813 _("unhandled stop_soon: %d"), (int) stop_soon
);
4815 case TARGET_WAITKIND_SPURIOUS
:
4816 if (handle_stop_requested (ecs
))
4818 context_switch (ecs
);
4819 resume (GDB_SIGNAL_0
);
4820 prepare_to_wait (ecs
);
4823 case TARGET_WAITKIND_THREAD_CREATED
:
4824 if (handle_stop_requested (ecs
))
4826 context_switch (ecs
);
4827 if (!switch_back_to_stepped_thread (ecs
))
4831 case TARGET_WAITKIND_EXITED
:
4832 case TARGET_WAITKIND_SIGNALLED
:
4833 inferior_ptid
= ecs
->ptid
;
4834 set_current_inferior (find_inferior_ptid (ecs
->ptid
));
4835 set_current_program_space (current_inferior ()->pspace
);
4836 handle_vfork_child_exec_or_exit (0);
4837 target_terminal::ours (); /* Must do this before mourn anyway. */
4839 /* Clearing any previous state of convenience variables. */
4840 clear_exit_convenience_vars ();
4842 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4844 /* Record the exit code in the convenience variable $_exitcode, so
4845 that the user can inspect this again later. */
4846 set_internalvar_integer (lookup_internalvar ("_exitcode"),
4847 (LONGEST
) ecs
->ws
.value
.integer
);
4849 /* Also record this in the inferior itself. */
4850 current_inferior ()->has_exit_code
= 1;
4851 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
4853 /* Support the --return-child-result option. */
4854 return_child_result_value
= ecs
->ws
.value
.integer
;
4856 gdb::observers::exited
.notify (ecs
->ws
.value
.integer
);
4860 struct gdbarch
*gdbarch
= current_inferior ()->gdbarch
;
4862 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
4864 /* Set the value of the internal variable $_exitsignal,
4865 which holds the signal uncaught by the inferior. */
4866 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
4867 gdbarch_gdb_signal_to_target (gdbarch
,
4868 ecs
->ws
.value
.sig
));
4872 /* We don't have access to the target's method used for
4873 converting between signal numbers (GDB's internal
4874 representation <-> target's representation).
4875 Therefore, we cannot do a good job at displaying this
4876 information to the user. It's better to just warn
4877 her about it (if infrun debugging is enabled), and
4880 fprintf_filtered (gdb_stdlog
, _("\
4881 Cannot fill $_exitsignal with the correct signal number.\n"));
4884 gdb::observers::signal_exited
.notify (ecs
->ws
.value
.sig
);
4887 gdb_flush (gdb_stdout
);
4888 target_mourn_inferior (inferior_ptid
);
4889 stop_print_frame
= 0;
4893 /* The following are the only cases in which we keep going;
4894 the above cases end in a continue or goto. */
4895 case TARGET_WAITKIND_FORKED
:
4896 case TARGET_WAITKIND_VFORKED
:
4897 /* Check whether the inferior is displaced stepping. */
4899 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
4900 struct gdbarch
*gdbarch
= regcache
->arch ();
4902 /* If checking displaced stepping is supported, and thread
4903 ecs->ptid is displaced stepping. */
4904 if (displaced_step_in_progress_thread (ecs
->event_thread
))
4906 struct inferior
*parent_inf
4907 = find_inferior_ptid (ecs
->ptid
);
4908 struct regcache
*child_regcache
;
4909 CORE_ADDR parent_pc
;
4911 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
4912 indicating that the displaced stepping of syscall instruction
4913 has been done. Perform cleanup for parent process here. Note
4914 that this operation also cleans up the child process for vfork,
4915 because their pages are shared. */
4916 displaced_step_fixup (ecs
->event_thread
, GDB_SIGNAL_TRAP
);
4917 /* Start a new step-over in another thread if there's one
4921 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
4923 struct displaced_step_inferior_state
*displaced
4924 = get_displaced_stepping_state (parent_inf
);
4926 /* Restore scratch pad for child process. */
4927 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
4930 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
4931 the child's PC is also within the scratchpad. Set the child's PC
4932 to the parent's PC value, which has already been fixed up.
4933 FIXME: we use the parent's aspace here, although we're touching
4934 the child, because the child hasn't been added to the inferior
4935 list yet at this point. */
4938 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
4940 parent_inf
->aspace
);
4941 /* Read PC value of parent process. */
4942 parent_pc
= regcache_read_pc (regcache
);
4944 if (debug_displaced
)
4945 fprintf_unfiltered (gdb_stdlog
,
4946 "displaced: write child pc from %s to %s\n",
4948 regcache_read_pc (child_regcache
)),
4949 paddress (gdbarch
, parent_pc
));
4951 regcache_write_pc (child_regcache
, parent_pc
);
4955 context_switch (ecs
);
4957 /* Immediately detach breakpoints from the child before there's
4958 any chance of letting the user delete breakpoints from the
4959 breakpoint lists. If we don't do this early, it's easy to
4960 leave left over traps in the child, vis: "break foo; catch
4961 fork; c; <fork>; del; c; <child calls foo>". We only follow
4962 the fork on the last `continue', and by that time the
4963 breakpoint at "foo" is long gone from the breakpoint table.
4964 If we vforked, then we don't need to unpatch here, since both
4965 parent and child are sharing the same memory pages; we'll
4966 need to unpatch at follow/detach time instead to be certain
4967 that new breakpoints added between catchpoint hit time and
4968 vfork follow are detached. */
4969 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
4971 /* This won't actually modify the breakpoint list, but will
4972 physically remove the breakpoints from the child. */
4973 detach_breakpoints (ecs
->ws
.value
.related_pid
);
4976 delete_just_stopped_threads_single_step_breakpoints ();
4978 /* In case the event is caught by a catchpoint, remember that
4979 the event is to be followed at the next resume of the thread,
4980 and not immediately. */
4981 ecs
->event_thread
->pending_follow
= ecs
->ws
;
4983 ecs
->event_thread
->suspend
.stop_pc
4984 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
4986 ecs
->event_thread
->control
.stop_bpstat
4987 = bpstat_stop_status (get_current_regcache ()->aspace (),
4988 ecs
->event_thread
->suspend
.stop_pc
,
4989 ecs
->event_thread
, &ecs
->ws
);
4991 if (handle_stop_requested (ecs
))
4994 /* If no catchpoint triggered for this, then keep going. Note
4995 that we're interested in knowing the bpstat actually causes a
4996 stop, not just if it may explain the signal. Software
4997 watchpoints, for example, always appear in the bpstat. */
4998 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5002 = (follow_fork_mode_string
== follow_fork_mode_child
);
5004 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5006 should_resume
= follow_fork ();
5008 thread_info
*parent
= ecs
->event_thread
;
5009 thread_info
*child
= find_thread_ptid (ecs
->ws
.value
.related_pid
);
5011 /* At this point, the parent is marked running, and the
5012 child is marked stopped. */
5014 /* If not resuming the parent, mark it stopped. */
5015 if (follow_child
&& !detach_fork
&& !non_stop
&& !sched_multi
)
5016 parent
->set_running (false);
5018 /* If resuming the child, mark it running. */
5019 if (follow_child
|| (!detach_fork
&& (non_stop
|| sched_multi
)))
5020 child
->set_running (true);
5022 /* In non-stop mode, also resume the other branch. */
5023 if (!detach_fork
&& (non_stop
5024 || (sched_multi
&& target_is_non_stop_p ())))
5027 switch_to_thread (parent
);
5029 switch_to_thread (child
);
5031 ecs
->event_thread
= inferior_thread ();
5032 ecs
->ptid
= inferior_ptid
;
5037 switch_to_thread (child
);
5039 switch_to_thread (parent
);
5041 ecs
->event_thread
= inferior_thread ();
5042 ecs
->ptid
= inferior_ptid
;
5050 process_event_stop_test (ecs
);
5053 case TARGET_WAITKIND_VFORK_DONE
:
5054 /* Done with the shared memory region. Re-insert breakpoints in
5055 the parent, and keep going. */
5057 context_switch (ecs
);
5059 current_inferior ()->waiting_for_vfork_done
= 0;
5060 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
5062 if (handle_stop_requested (ecs
))
5065 /* This also takes care of reinserting breakpoints in the
5066 previously locked inferior. */
5070 case TARGET_WAITKIND_EXECD
:
5072 /* Note we can't read registers yet (the stop_pc), because we
5073 don't yet know the inferior's post-exec architecture.
5074 'stop_pc' is explicitly read below instead. */
5075 switch_to_thread_no_regs (ecs
->event_thread
);
5077 /* Do whatever is necessary to the parent branch of the vfork. */
5078 handle_vfork_child_exec_or_exit (1);
5080 /* This causes the eventpoints and symbol table to be reset.
5081 Must do this now, before trying to determine whether to
5083 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
5085 /* In follow_exec we may have deleted the original thread and
5086 created a new one. Make sure that the event thread is the
5087 execd thread for that case (this is a nop otherwise). */
5088 ecs
->event_thread
= inferior_thread ();
5090 ecs
->event_thread
->suspend
.stop_pc
5091 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
5093 ecs
->event_thread
->control
.stop_bpstat
5094 = bpstat_stop_status (get_current_regcache ()->aspace (),
5095 ecs
->event_thread
->suspend
.stop_pc
,
5096 ecs
->event_thread
, &ecs
->ws
);
5098 /* Note that this may be referenced from inside
5099 bpstat_stop_status above, through inferior_has_execd. */
5100 xfree (ecs
->ws
.value
.execd_pathname
);
5101 ecs
->ws
.value
.execd_pathname
= NULL
;
5103 if (handle_stop_requested (ecs
))
5106 /* If no catchpoint triggered for this, then keep going. */
5107 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5109 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5113 process_event_stop_test (ecs
);
5116 /* Be careful not to try to gather much state about a thread
5117 that's in a syscall. It's frequently a losing proposition. */
5118 case TARGET_WAITKIND_SYSCALL_ENTRY
:
5119 /* Getting the current syscall number. */
5120 if (handle_syscall_event (ecs
) == 0)
5121 process_event_stop_test (ecs
);
5124 /* Before examining the threads further, step this thread to
5125 get it entirely out of the syscall. (We get notice of the
5126 event when the thread is just on the verge of exiting a
5127 syscall. Stepping one instruction seems to get it back
5129 case TARGET_WAITKIND_SYSCALL_RETURN
:
5130 if (handle_syscall_event (ecs
) == 0)
5131 process_event_stop_test (ecs
);
5134 case TARGET_WAITKIND_STOPPED
:
5135 handle_signal_stop (ecs
);
5138 case TARGET_WAITKIND_NO_HISTORY
:
5139 /* Reverse execution: target ran out of history info. */
5141 /* Switch to the stopped thread. */
5142 context_switch (ecs
);
5144 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
5146 delete_just_stopped_threads_single_step_breakpoints ();
5147 ecs
->event_thread
->suspend
.stop_pc
5148 = regcache_read_pc (get_thread_regcache (inferior_thread ()));
5150 if (handle_stop_requested (ecs
))
5153 gdb::observers::no_history
.notify ();
5159 /* Restart threads back to what they were trying to do back when we
5160 paused them for an in-line step-over. The EVENT_THREAD thread is
5164 restart_threads (struct thread_info
*event_thread
)
5166 /* In case the instruction just stepped spawned a new thread. */
5167 update_thread_list ();
5169 for (thread_info
*tp
: all_non_exited_threads ())
5171 if (tp
== event_thread
)
5174 fprintf_unfiltered (gdb_stdlog
,
5175 "infrun: restart threads: "
5176 "[%s] is event thread\n",
5177 target_pid_to_str (tp
->ptid
).c_str ());
5181 if (!(tp
->state
== THREAD_RUNNING
|| tp
->control
.in_infcall
))
5184 fprintf_unfiltered (gdb_stdlog
,
5185 "infrun: restart threads: "
5186 "[%s] not meant to be running\n",
5187 target_pid_to_str (tp
->ptid
).c_str ());
5194 fprintf_unfiltered (gdb_stdlog
,
5195 "infrun: restart threads: [%s] resumed\n",
5196 target_pid_to_str (tp
->ptid
).c_str ());
5197 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
5201 if (thread_is_in_step_over_chain (tp
))
5204 fprintf_unfiltered (gdb_stdlog
,
5205 "infrun: restart threads: "
5206 "[%s] needs step-over\n",
5207 target_pid_to_str (tp
->ptid
).c_str ());
5208 gdb_assert (!tp
->resumed
);
5213 if (tp
->suspend
.waitstatus_pending_p
)
5216 fprintf_unfiltered (gdb_stdlog
,
5217 "infrun: restart threads: "
5218 "[%s] has pending status\n",
5219 target_pid_to_str (tp
->ptid
).c_str ());
5224 gdb_assert (!tp
->stop_requested
);
5226 /* If some thread needs to start a step-over at this point, it
5227 should still be in the step-over queue, and thus skipped
5229 if (thread_still_needs_step_over (tp
))
5231 internal_error (__FILE__
, __LINE__
,
5232 "thread [%s] needs a step-over, but not in "
5233 "step-over queue\n",
5234 target_pid_to_str (tp
->ptid
).c_str ());
5237 if (currently_stepping (tp
))
5240 fprintf_unfiltered (gdb_stdlog
,
5241 "infrun: restart threads: [%s] was stepping\n",
5242 target_pid_to_str (tp
->ptid
).c_str ());
5243 keep_going_stepped_thread (tp
);
5247 struct execution_control_state ecss
;
5248 struct execution_control_state
*ecs
= &ecss
;
5251 fprintf_unfiltered (gdb_stdlog
,
5252 "infrun: restart threads: [%s] continuing\n",
5253 target_pid_to_str (tp
->ptid
).c_str ());
5254 reset_ecs (ecs
, tp
);
5255 switch_to_thread (tp
);
5256 keep_going_pass_signal (ecs
);
5261 /* Callback for iterate_over_threads. Find a resumed thread that has
5262 a pending waitstatus. */
5265 resumed_thread_with_pending_status (struct thread_info
*tp
,
5269 && tp
->suspend
.waitstatus_pending_p
);
5272 /* Called when we get an event that may finish an in-line or
5273 out-of-line (displaced stepping) step-over started previously.
5274 Return true if the event is processed and we should go back to the
5275 event loop; false if the caller should continue processing the
5279 finish_step_over (struct execution_control_state
*ecs
)
5281 int had_step_over_info
;
5283 displaced_step_fixup (ecs
->event_thread
,
5284 ecs
->event_thread
->suspend
.stop_signal
);
5286 had_step_over_info
= step_over_info_valid_p ();
5288 if (had_step_over_info
)
5290 /* If we're stepping over a breakpoint with all threads locked,
5291 then only the thread that was stepped should be reporting
5293 gdb_assert (ecs
->event_thread
->control
.trap_expected
);
5295 clear_step_over_info ();
5298 if (!target_is_non_stop_p ())
5301 /* Start a new step-over in another thread if there's one that
5305 /* If we were stepping over a breakpoint before, and haven't started
5306 a new in-line step-over sequence, then restart all other threads
5307 (except the event thread). We can't do this in all-stop, as then
5308 e.g., we wouldn't be able to issue any other remote packet until
5309 these other threads stop. */
5310 if (had_step_over_info
&& !step_over_info_valid_p ())
5312 struct thread_info
*pending
;
5314 /* If we only have threads with pending statuses, the restart
5315 below won't restart any thread and so nothing re-inserts the
5316 breakpoint we just stepped over. But we need it inserted
5317 when we later process the pending events, otherwise if
5318 another thread has a pending event for this breakpoint too,
5319 we'd discard its event (because the breakpoint that
5320 originally caused the event was no longer inserted). */
5321 context_switch (ecs
);
5322 insert_breakpoints ();
5325 scoped_restore save_defer_tc
5326 = make_scoped_defer_target_commit_resume ();
5327 restart_threads (ecs
->event_thread
);
5329 target_commit_resume ();
5331 /* If we have events pending, go through handle_inferior_event
5332 again, picking up a pending event at random. This avoids
5333 thread starvation. */
5335 /* But not if we just stepped over a watchpoint in order to let
5336 the instruction execute so we can evaluate its expression.
5337 The set of watchpoints that triggered is recorded in the
5338 breakpoint objects themselves (see bp->watchpoint_triggered).
5339 If we processed another event first, that other event could
5340 clobber this info. */
5341 if (ecs
->event_thread
->stepping_over_watchpoint
)
5344 pending
= iterate_over_threads (resumed_thread_with_pending_status
,
5346 if (pending
!= NULL
)
5348 struct thread_info
*tp
= ecs
->event_thread
;
5349 struct regcache
*regcache
;
5353 fprintf_unfiltered (gdb_stdlog
,
5354 "infrun: found resumed threads with "
5355 "pending events, saving status\n");
5358 gdb_assert (pending
!= tp
);
5360 /* Record the event thread's event for later. */
5361 save_waitstatus (tp
, &ecs
->ws
);
5362 /* This was cleared early, by handle_inferior_event. Set it
5363 so this pending event is considered by
5367 gdb_assert (!tp
->executing
);
5369 regcache
= get_thread_regcache (tp
);
5370 tp
->suspend
.stop_pc
= regcache_read_pc (regcache
);
5374 fprintf_unfiltered (gdb_stdlog
,
5375 "infrun: saved stop_pc=%s for %s "
5376 "(currently_stepping=%d)\n",
5377 paddress (target_gdbarch (),
5378 tp
->suspend
.stop_pc
),
5379 target_pid_to_str (tp
->ptid
).c_str (),
5380 currently_stepping (tp
));
5383 /* This in-line step-over finished; clear this so we won't
5384 start a new one. This is what handle_signal_stop would
5385 do, if we returned false. */
5386 tp
->stepping_over_breakpoint
= 0;
5388 /* Wake up the event loop again. */
5389 mark_async_event_handler (infrun_async_inferior_event_token
);
5391 prepare_to_wait (ecs
);
5399 /* Come here when the program has stopped with a signal. */
5402 handle_signal_stop (struct execution_control_state
*ecs
)
5404 struct frame_info
*frame
;
5405 struct gdbarch
*gdbarch
;
5406 int stopped_by_watchpoint
;
5407 enum stop_kind stop_soon
;
5410 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
5412 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
5414 /* Do we need to clean up the state of a thread that has
5415 completed a displaced single-step? (Doing so usually affects
5416 the PC, so do it here, before we set stop_pc.) */
5417 if (finish_step_over (ecs
))
5420 /* If we either finished a single-step or hit a breakpoint, but
5421 the user wanted this thread to be stopped, pretend we got a
5422 SIG0 (generic unsignaled stop). */
5423 if (ecs
->event_thread
->stop_requested
5424 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5425 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5427 ecs
->event_thread
->suspend
.stop_pc
5428 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
5432 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
5433 struct gdbarch
*reg_gdbarch
= regcache
->arch ();
5434 scoped_restore save_inferior_ptid
= make_scoped_restore (&inferior_ptid
);
5436 inferior_ptid
= ecs
->ptid
;
5438 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
5439 paddress (reg_gdbarch
,
5440 ecs
->event_thread
->suspend
.stop_pc
));
5441 if (target_stopped_by_watchpoint ())
5445 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
5447 if (target_stopped_data_address (current_top_target (), &addr
))
5448 fprintf_unfiltered (gdb_stdlog
,
5449 "infrun: stopped data address = %s\n",
5450 paddress (reg_gdbarch
, addr
));
5452 fprintf_unfiltered (gdb_stdlog
,
5453 "infrun: (no data address available)\n");
5457 /* This is originated from start_remote(), start_inferior() and
5458 shared libraries hook functions. */
5459 stop_soon
= get_inferior_stop_soon (ecs
);
5460 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
5462 context_switch (ecs
);
5464 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5465 stop_print_frame
= 1;
5470 /* This originates from attach_command(). We need to overwrite
5471 the stop_signal here, because some kernels don't ignore a
5472 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5473 See more comments in inferior.h. On the other hand, if we
5474 get a non-SIGSTOP, report it to the user - assume the backend
5475 will handle the SIGSTOP if it should show up later.
5477 Also consider that the attach is complete when we see a
5478 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5479 target extended-remote report it instead of a SIGSTOP
5480 (e.g. gdbserver). We already rely on SIGTRAP being our
5481 signal, so this is no exception.
5483 Also consider that the attach is complete when we see a
5484 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5485 the target to stop all threads of the inferior, in case the
5486 low level attach operation doesn't stop them implicitly. If
5487 they weren't stopped implicitly, then the stub will report a
5488 GDB_SIGNAL_0, meaning: stopped for no particular reason
5489 other than GDB's request. */
5490 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5491 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
5492 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5493 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
5495 stop_print_frame
= 1;
5497 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5501 /* See if something interesting happened to the non-current thread. If
5502 so, then switch to that thread. */
5503 if (ecs
->ptid
!= inferior_ptid
)
5506 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
5508 context_switch (ecs
);
5510 if (deprecated_context_hook
)
5511 deprecated_context_hook (ecs
->event_thread
->global_num
);
5514 /* At this point, get hold of the now-current thread's frame. */
5515 frame
= get_current_frame ();
5516 gdbarch
= get_frame_arch (frame
);
5518 /* Pull the single step breakpoints out of the target. */
5519 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5521 struct regcache
*regcache
;
5524 regcache
= get_thread_regcache (ecs
->event_thread
);
5525 const address_space
*aspace
= regcache
->aspace ();
5527 pc
= regcache_read_pc (regcache
);
5529 /* However, before doing so, if this single-step breakpoint was
5530 actually for another thread, set this thread up for moving
5532 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
5535 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
5539 fprintf_unfiltered (gdb_stdlog
,
5540 "infrun: [%s] hit another thread's "
5541 "single-step breakpoint\n",
5542 target_pid_to_str (ecs
->ptid
).c_str ());
5544 ecs
->hit_singlestep_breakpoint
= 1;
5551 fprintf_unfiltered (gdb_stdlog
,
5552 "infrun: [%s] hit its "
5553 "single-step breakpoint\n",
5554 target_pid_to_str (ecs
->ptid
).c_str ());
5558 delete_just_stopped_threads_single_step_breakpoints ();
5560 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5561 && ecs
->event_thread
->control
.trap_expected
5562 && ecs
->event_thread
->stepping_over_watchpoint
)
5563 stopped_by_watchpoint
= 0;
5565 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
5567 /* If necessary, step over this watchpoint. We'll be back to display
5569 if (stopped_by_watchpoint
5570 && (target_have_steppable_watchpoint
5571 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
5573 /* At this point, we are stopped at an instruction which has
5574 attempted to write to a piece of memory under control of
5575 a watchpoint. The instruction hasn't actually executed
5576 yet. If we were to evaluate the watchpoint expression
5577 now, we would get the old value, and therefore no change
5578 would seem to have occurred.
5580 In order to make watchpoints work `right', we really need
5581 to complete the memory write, and then evaluate the
5582 watchpoint expression. We do this by single-stepping the
5585 It may not be necessary to disable the watchpoint to step over
5586 it. For example, the PA can (with some kernel cooperation)
5587 single step over a watchpoint without disabling the watchpoint.
5589 It is far more common to need to disable a watchpoint to step
5590 the inferior over it. If we have non-steppable watchpoints,
5591 we must disable the current watchpoint; it's simplest to
5592 disable all watchpoints.
5594 Any breakpoint at PC must also be stepped over -- if there's
5595 one, it will have already triggered before the watchpoint
5596 triggered, and we either already reported it to the user, or
5597 it didn't cause a stop and we called keep_going. In either
5598 case, if there was a breakpoint at PC, we must be trying to
5600 ecs
->event_thread
->stepping_over_watchpoint
= 1;
5605 ecs
->event_thread
->stepping_over_breakpoint
= 0;
5606 ecs
->event_thread
->stepping_over_watchpoint
= 0;
5607 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
5608 ecs
->event_thread
->control
.stop_step
= 0;
5609 stop_print_frame
= 1;
5610 stopped_by_random_signal
= 0;
5611 bpstat stop_chain
= NULL
;
5613 /* Hide inlined functions starting here, unless we just performed stepi or
5614 nexti. After stepi and nexti, always show the innermost frame (not any
5615 inline function call sites). */
5616 if (ecs
->event_thread
->control
.step_range_end
!= 1)
5618 const address_space
*aspace
5619 = get_thread_regcache (ecs
->event_thread
)->aspace ();
5621 /* skip_inline_frames is expensive, so we avoid it if we can
5622 determine that the address is one where functions cannot have
5623 been inlined. This improves performance with inferiors that
5624 load a lot of shared libraries, because the solib event
5625 breakpoint is defined as the address of a function (i.e. not
5626 inline). Note that we have to check the previous PC as well
5627 as the current one to catch cases when we have just
5628 single-stepped off a breakpoint prior to reinstating it.
5629 Note that we're assuming that the code we single-step to is
5630 not inline, but that's not definitive: there's nothing
5631 preventing the event breakpoint function from containing
5632 inlined code, and the single-step ending up there. If the
5633 user had set a breakpoint on that inlined code, the missing
5634 skip_inline_frames call would break things. Fortunately
5635 that's an extremely unlikely scenario. */
5636 if (!pc_at_non_inline_function (aspace
,
5637 ecs
->event_thread
->suspend
.stop_pc
,
5639 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5640 && ecs
->event_thread
->control
.trap_expected
5641 && pc_at_non_inline_function (aspace
,
5642 ecs
->event_thread
->prev_pc
,
5645 stop_chain
= build_bpstat_chain (aspace
,
5646 ecs
->event_thread
->suspend
.stop_pc
,
5648 skip_inline_frames (ecs
->event_thread
, stop_chain
);
5650 /* Re-fetch current thread's frame in case that invalidated
5652 frame
= get_current_frame ();
5653 gdbarch
= get_frame_arch (frame
);
5657 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5658 && ecs
->event_thread
->control
.trap_expected
5659 && gdbarch_single_step_through_delay_p (gdbarch
)
5660 && currently_stepping (ecs
->event_thread
))
5662 /* We're trying to step off a breakpoint. Turns out that we're
5663 also on an instruction that needs to be stepped multiple
5664 times before it's been fully executing. E.g., architectures
5665 with a delay slot. It needs to be stepped twice, once for
5666 the instruction and once for the delay slot. */
5667 int step_through_delay
5668 = gdbarch_single_step_through_delay (gdbarch
, frame
);
5670 if (debug_infrun
&& step_through_delay
)
5671 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
5672 if (ecs
->event_thread
->control
.step_range_end
== 0
5673 && step_through_delay
)
5675 /* The user issued a continue when stopped at a breakpoint.
5676 Set up for another trap and get out of here. */
5677 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5681 else if (step_through_delay
)
5683 /* The user issued a step when stopped at a breakpoint.
5684 Maybe we should stop, maybe we should not - the delay
5685 slot *might* correspond to a line of source. In any
5686 case, don't decide that here, just set
5687 ecs->stepping_over_breakpoint, making sure we
5688 single-step again before breakpoints are re-inserted. */
5689 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5693 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
5694 handles this event. */
5695 ecs
->event_thread
->control
.stop_bpstat
5696 = bpstat_stop_status (get_current_regcache ()->aspace (),
5697 ecs
->event_thread
->suspend
.stop_pc
,
5698 ecs
->event_thread
, &ecs
->ws
, stop_chain
);
5700 /* Following in case break condition called a
5702 stop_print_frame
= 1;
5704 /* This is where we handle "moribund" watchpoints. Unlike
5705 software breakpoints traps, hardware watchpoint traps are
5706 always distinguishable from random traps. If no high-level
5707 watchpoint is associated with the reported stop data address
5708 anymore, then the bpstat does not explain the signal ---
5709 simply make sure to ignore it if `stopped_by_watchpoint' is
5713 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5714 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5716 && stopped_by_watchpoint
)
5717 fprintf_unfiltered (gdb_stdlog
,
5718 "infrun: no user watchpoint explains "
5719 "watchpoint SIGTRAP, ignoring\n");
5721 /* NOTE: cagney/2003-03-29: These checks for a random signal
5722 at one stage in the past included checks for an inferior
5723 function call's call dummy's return breakpoint. The original
5724 comment, that went with the test, read:
5726 ``End of a stack dummy. Some systems (e.g. Sony news) give
5727 another signal besides SIGTRAP, so check here as well as
5730 If someone ever tries to get call dummys on a
5731 non-executable stack to work (where the target would stop
5732 with something like a SIGSEGV), then those tests might need
5733 to be re-instated. Given, however, that the tests were only
5734 enabled when momentary breakpoints were not being used, I
5735 suspect that it won't be the case.
5737 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
5738 be necessary for call dummies on a non-executable stack on
5741 /* See if the breakpoints module can explain the signal. */
5743 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5744 ecs
->event_thread
->suspend
.stop_signal
);
5746 /* Maybe this was a trap for a software breakpoint that has since
5748 if (random_signal
&& target_stopped_by_sw_breakpoint ())
5750 if (program_breakpoint_here_p (gdbarch
,
5751 ecs
->event_thread
->suspend
.stop_pc
))
5753 struct regcache
*regcache
;
5756 /* Re-adjust PC to what the program would see if GDB was not
5758 regcache
= get_thread_regcache (ecs
->event_thread
);
5759 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
5762 gdb::optional
<scoped_restore_tmpl
<int>>
5763 restore_operation_disable
;
5765 if (record_full_is_used ())
5766 restore_operation_disable
.emplace
5767 (record_full_gdb_operation_disable_set ());
5769 regcache_write_pc (regcache
,
5770 ecs
->event_thread
->suspend
.stop_pc
+ decr_pc
);
5775 /* A delayed software breakpoint event. Ignore the trap. */
5777 fprintf_unfiltered (gdb_stdlog
,
5778 "infrun: delayed software breakpoint "
5779 "trap, ignoring\n");
5784 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
5785 has since been removed. */
5786 if (random_signal
&& target_stopped_by_hw_breakpoint ())
5788 /* A delayed hardware breakpoint event. Ignore the trap. */
5790 fprintf_unfiltered (gdb_stdlog
,
5791 "infrun: delayed hardware breakpoint/watchpoint "
5792 "trap, ignoring\n");
5796 /* If not, perhaps stepping/nexting can. */
5798 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5799 && currently_stepping (ecs
->event_thread
));
5801 /* Perhaps the thread hit a single-step breakpoint of _another_
5802 thread. Single-step breakpoints are transparent to the
5803 breakpoints module. */
5805 random_signal
= !ecs
->hit_singlestep_breakpoint
;
5807 /* No? Perhaps we got a moribund watchpoint. */
5809 random_signal
= !stopped_by_watchpoint
;
5811 /* Always stop if the user explicitly requested this thread to
5813 if (ecs
->event_thread
->stop_requested
)
5817 fprintf_unfiltered (gdb_stdlog
, "infrun: user-requested stop\n");
5820 /* For the program's own signals, act according to
5821 the signal handling tables. */
5825 /* Signal not for debugging purposes. */
5826 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
5827 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
5830 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
5831 gdb_signal_to_symbol_string (stop_signal
));
5833 stopped_by_random_signal
= 1;
5835 /* Always stop on signals if we're either just gaining control
5836 of the program, or the user explicitly requested this thread
5837 to remain stopped. */
5838 if (stop_soon
!= NO_STOP_QUIETLY
5839 || ecs
->event_thread
->stop_requested
5841 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
5847 /* Notify observers the signal has "handle print" set. Note we
5848 returned early above if stopping; normal_stop handles the
5849 printing in that case. */
5850 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
5852 /* The signal table tells us to print about this signal. */
5853 target_terminal::ours_for_output ();
5854 gdb::observers::signal_received
.notify (ecs
->event_thread
->suspend
.stop_signal
);
5855 target_terminal::inferior ();
5858 /* Clear the signal if it should not be passed. */
5859 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
5860 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5862 if (ecs
->event_thread
->prev_pc
== ecs
->event_thread
->suspend
.stop_pc
5863 && ecs
->event_thread
->control
.trap_expected
5864 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
5866 /* We were just starting a new sequence, attempting to
5867 single-step off of a breakpoint and expecting a SIGTRAP.
5868 Instead this signal arrives. This signal will take us out
5869 of the stepping range so GDB needs to remember to, when
5870 the signal handler returns, resume stepping off that
5872 /* To simplify things, "continue" is forced to use the same
5873 code paths as single-step - set a breakpoint at the
5874 signal return address and then, once hit, step off that
5877 fprintf_unfiltered (gdb_stdlog
,
5878 "infrun: signal arrived while stepping over "
5881 insert_hp_step_resume_breakpoint_at_frame (frame
);
5882 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
5883 /* Reset trap_expected to ensure breakpoints are re-inserted. */
5884 ecs
->event_thread
->control
.trap_expected
= 0;
5886 /* If we were nexting/stepping some other thread, switch to
5887 it, so that we don't continue it, losing control. */
5888 if (!switch_back_to_stepped_thread (ecs
))
5893 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
5894 && (pc_in_thread_step_range (ecs
->event_thread
->suspend
.stop_pc
,
5896 || ecs
->event_thread
->control
.step_range_end
== 1)
5897 && frame_id_eq (get_stack_frame_id (frame
),
5898 ecs
->event_thread
->control
.step_stack_frame_id
)
5899 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
5901 /* The inferior is about to take a signal that will take it
5902 out of the single step range. Set a breakpoint at the
5903 current PC (which is presumably where the signal handler
5904 will eventually return) and then allow the inferior to
5907 Note that this is only needed for a signal delivered
5908 while in the single-step range. Nested signals aren't a
5909 problem as they eventually all return. */
5911 fprintf_unfiltered (gdb_stdlog
,
5912 "infrun: signal may take us out of "
5913 "single-step range\n");
5915 clear_step_over_info ();
5916 insert_hp_step_resume_breakpoint_at_frame (frame
);
5917 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
5918 /* Reset trap_expected to ensure breakpoints are re-inserted. */
5919 ecs
->event_thread
->control
.trap_expected
= 0;
5924 /* Note: step_resume_breakpoint may be non-NULL. This occurs
5925 when either there's a nested signal, or when there's a
5926 pending signal enabled just as the signal handler returns
5927 (leaving the inferior at the step-resume-breakpoint without
5928 actually executing it). Either way continue until the
5929 breakpoint is really hit. */
5931 if (!switch_back_to_stepped_thread (ecs
))
5934 fprintf_unfiltered (gdb_stdlog
,
5935 "infrun: random signal, keep going\n");
5942 process_event_stop_test (ecs
);
5945 /* Come here when we've got some debug event / signal we can explain
5946 (IOW, not a random signal), and test whether it should cause a
5947 stop, or whether we should resume the inferior (transparently).
5948 E.g., could be a breakpoint whose condition evaluates false; we
5949 could be still stepping within the line; etc. */
5952 process_event_stop_test (struct execution_control_state
*ecs
)
5954 struct symtab_and_line stop_pc_sal
;
5955 struct frame_info
*frame
;
5956 struct gdbarch
*gdbarch
;
5957 CORE_ADDR jmp_buf_pc
;
5958 struct bpstat_what what
;
5960 /* Handle cases caused by hitting a breakpoint. */
5962 frame
= get_current_frame ();
5963 gdbarch
= get_frame_arch (frame
);
5965 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
5967 if (what
.call_dummy
)
5969 stop_stack_dummy
= what
.call_dummy
;
5972 /* A few breakpoint types have callbacks associated (e.g.,
5973 bp_jit_event). Run them now. */
5974 bpstat_run_callbacks (ecs
->event_thread
->control
.stop_bpstat
);
5976 /* If we hit an internal event that triggers symbol changes, the
5977 current frame will be invalidated within bpstat_what (e.g., if we
5978 hit an internal solib event). Re-fetch it. */
5979 frame
= get_current_frame ();
5980 gdbarch
= get_frame_arch (frame
);
5982 switch (what
.main_action
)
5984 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
5985 /* If we hit the breakpoint at longjmp while stepping, we
5986 install a momentary breakpoint at the target of the
5990 fprintf_unfiltered (gdb_stdlog
,
5991 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
5993 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5995 if (what
.is_longjmp
)
5997 struct value
*arg_value
;
5999 /* If we set the longjmp breakpoint via a SystemTap probe,
6000 then use it to extract the arguments. The destination PC
6001 is the third argument to the probe. */
6002 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
6005 jmp_buf_pc
= value_as_address (arg_value
);
6006 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
6008 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
6009 || !gdbarch_get_longjmp_target (gdbarch
,
6010 frame
, &jmp_buf_pc
))
6013 fprintf_unfiltered (gdb_stdlog
,
6014 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
6015 "(!gdbarch_get_longjmp_target)\n");
6020 /* Insert a breakpoint at resume address. */
6021 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
6024 check_exception_resume (ecs
, frame
);
6028 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
6030 struct frame_info
*init_frame
;
6032 /* There are several cases to consider.
6034 1. The initiating frame no longer exists. In this case we
6035 must stop, because the exception or longjmp has gone too
6038 2. The initiating frame exists, and is the same as the
6039 current frame. We stop, because the exception or longjmp
6042 3. The initiating frame exists and is different from the
6043 current frame. This means the exception or longjmp has
6044 been caught beneath the initiating frame, so keep going.
6046 4. longjmp breakpoint has been placed just to protect
6047 against stale dummy frames and user is not interested in
6048 stopping around longjmps. */
6051 fprintf_unfiltered (gdb_stdlog
,
6052 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
6054 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
6056 delete_exception_resume_breakpoint (ecs
->event_thread
);
6058 if (what
.is_longjmp
)
6060 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
6062 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
6070 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
6074 struct frame_id current_id
6075 = get_frame_id (get_current_frame ());
6076 if (frame_id_eq (current_id
,
6077 ecs
->event_thread
->initiating_frame
))
6079 /* Case 2. Fall through. */
6089 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6091 delete_step_resume_breakpoint (ecs
->event_thread
);
6093 end_stepping_range (ecs
);
6097 case BPSTAT_WHAT_SINGLE
:
6099 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
6100 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6101 /* Still need to check other stuff, at least the case where we
6102 are stepping and step out of the right range. */
6105 case BPSTAT_WHAT_STEP_RESUME
:
6107 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
6109 delete_step_resume_breakpoint (ecs
->event_thread
);
6110 if (ecs
->event_thread
->control
.proceed_to_finish
6111 && execution_direction
== EXEC_REVERSE
)
6113 struct thread_info
*tp
= ecs
->event_thread
;
6115 /* We are finishing a function in reverse, and just hit the
6116 step-resume breakpoint at the start address of the
6117 function, and we're almost there -- just need to back up
6118 by one more single-step, which should take us back to the
6120 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
6124 fill_in_stop_func (gdbarch
, ecs
);
6125 if (ecs
->event_thread
->suspend
.stop_pc
== ecs
->stop_func_start
6126 && execution_direction
== EXEC_REVERSE
)
6128 /* We are stepping over a function call in reverse, and just
6129 hit the step-resume breakpoint at the start address of
6130 the function. Go back to single-stepping, which should
6131 take us back to the function call. */
6132 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6138 case BPSTAT_WHAT_STOP_NOISY
:
6140 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
6141 stop_print_frame
= 1;
6143 /* Assume the thread stopped for a breapoint. We'll still check
6144 whether a/the breakpoint is there when the thread is next
6146 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6151 case BPSTAT_WHAT_STOP_SILENT
:
6153 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
6154 stop_print_frame
= 0;
6156 /* Assume the thread stopped for a breapoint. We'll still check
6157 whether a/the breakpoint is there when the thread is next
6159 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6163 case BPSTAT_WHAT_HP_STEP_RESUME
:
6165 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
6167 delete_step_resume_breakpoint (ecs
->event_thread
);
6168 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
6170 /* Back when the step-resume breakpoint was inserted, we
6171 were trying to single-step off a breakpoint. Go back to
6173 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6174 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6180 case BPSTAT_WHAT_KEEP_CHECKING
:
6184 /* If we stepped a permanent breakpoint and we had a high priority
6185 step-resume breakpoint for the address we stepped, but we didn't
6186 hit it, then we must have stepped into the signal handler. The
6187 step-resume was only necessary to catch the case of _not_
6188 stepping into the handler, so delete it, and fall through to
6189 checking whether the step finished. */
6190 if (ecs
->event_thread
->stepped_breakpoint
)
6192 struct breakpoint
*sr_bp
6193 = ecs
->event_thread
->control
.step_resume_breakpoint
;
6196 && sr_bp
->loc
->permanent
6197 && sr_bp
->type
== bp_hp_step_resume
6198 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
6201 fprintf_unfiltered (gdb_stdlog
,
6202 "infrun: stepped permanent breakpoint, stopped in "
6204 delete_step_resume_breakpoint (ecs
->event_thread
);
6205 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6209 /* We come here if we hit a breakpoint but should not stop for it.
6210 Possibly we also were stepping and should stop for that. So fall
6211 through and test for stepping. But, if not stepping, do not
6214 /* In all-stop mode, if we're currently stepping but have stopped in
6215 some other thread, we need to switch back to the stepped thread. */
6216 if (switch_back_to_stepped_thread (ecs
))
6219 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
6222 fprintf_unfiltered (gdb_stdlog
,
6223 "infrun: step-resume breakpoint is inserted\n");
6225 /* Having a step-resume breakpoint overrides anything
6226 else having to do with stepping commands until
6227 that breakpoint is reached. */
6232 if (ecs
->event_thread
->control
.step_range_end
== 0)
6235 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
6236 /* Likewise if we aren't even stepping. */
6241 /* Re-fetch current thread's frame in case the code above caused
6242 the frame cache to be re-initialized, making our FRAME variable
6243 a dangling pointer. */
6244 frame
= get_current_frame ();
6245 gdbarch
= get_frame_arch (frame
);
6246 fill_in_stop_func (gdbarch
, ecs
);
6248 /* If stepping through a line, keep going if still within it.
6250 Note that step_range_end is the address of the first instruction
6251 beyond the step range, and NOT the address of the last instruction
6254 Note also that during reverse execution, we may be stepping
6255 through a function epilogue and therefore must detect when
6256 the current-frame changes in the middle of a line. */
6258 if (pc_in_thread_step_range (ecs
->event_thread
->suspend
.stop_pc
,
6260 && (execution_direction
!= EXEC_REVERSE
6261 || frame_id_eq (get_frame_id (frame
),
6262 ecs
->event_thread
->control
.step_frame_id
)))
6266 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
6267 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
6268 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
6270 /* Tentatively re-enable range stepping; `resume' disables it if
6271 necessary (e.g., if we're stepping over a breakpoint or we
6272 have software watchpoints). */
6273 ecs
->event_thread
->control
.may_range_step
= 1;
6275 /* When stepping backward, stop at beginning of line range
6276 (unless it's the function entry point, in which case
6277 keep going back to the call point). */
6278 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6279 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
6280 && stop_pc
!= ecs
->stop_func_start
6281 && execution_direction
== EXEC_REVERSE
)
6282 end_stepping_range (ecs
);
6289 /* We stepped out of the stepping range. */
6291 /* If we are stepping at the source level and entered the runtime
6292 loader dynamic symbol resolution code...
6294 EXEC_FORWARD: we keep on single stepping until we exit the run
6295 time loader code and reach the callee's address.
6297 EXEC_REVERSE: we've already executed the callee (backward), and
6298 the runtime loader code is handled just like any other
6299 undebuggable function call. Now we need only keep stepping
6300 backward through the trampoline code, and that's handled further
6301 down, so there is nothing for us to do here. */
6303 if (execution_direction
!= EXEC_REVERSE
6304 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6305 && in_solib_dynsym_resolve_code (ecs
->event_thread
->suspend
.stop_pc
))
6307 CORE_ADDR pc_after_resolver
=
6308 gdbarch_skip_solib_resolver (gdbarch
,
6309 ecs
->event_thread
->suspend
.stop_pc
);
6312 fprintf_unfiltered (gdb_stdlog
,
6313 "infrun: stepped into dynsym resolve code\n");
6315 if (pc_after_resolver
)
6317 /* Set up a step-resume breakpoint at the address
6318 indicated by SKIP_SOLIB_RESOLVER. */
6319 symtab_and_line sr_sal
;
6320 sr_sal
.pc
= pc_after_resolver
;
6321 sr_sal
.pspace
= get_frame_program_space (frame
);
6323 insert_step_resume_breakpoint_at_sal (gdbarch
,
6324 sr_sal
, null_frame_id
);
6331 /* Step through an indirect branch thunk. */
6332 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6333 && gdbarch_in_indirect_branch_thunk (gdbarch
,
6334 ecs
->event_thread
->suspend
.stop_pc
))
6337 fprintf_unfiltered (gdb_stdlog
,
6338 "infrun: stepped into indirect branch thunk\n");
6343 if (ecs
->event_thread
->control
.step_range_end
!= 1
6344 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6345 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6346 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
6349 fprintf_unfiltered (gdb_stdlog
,
6350 "infrun: stepped into signal trampoline\n");
6351 /* The inferior, while doing a "step" or "next", has ended up in
6352 a signal trampoline (either by a signal being delivered or by
6353 the signal handler returning). Just single-step until the
6354 inferior leaves the trampoline (either by calling the handler
6360 /* If we're in the return path from a shared library trampoline,
6361 we want to proceed through the trampoline when stepping. */
6362 /* macro/2012-04-25: This needs to come before the subroutine
6363 call check below as on some targets return trampolines look
6364 like subroutine calls (MIPS16 return thunks). */
6365 if (gdbarch_in_solib_return_trampoline (gdbarch
,
6366 ecs
->event_thread
->suspend
.stop_pc
,
6367 ecs
->stop_func_name
)
6368 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6370 /* Determine where this trampoline returns. */
6371 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6372 CORE_ADDR real_stop_pc
6373 = gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6376 fprintf_unfiltered (gdb_stdlog
,
6377 "infrun: stepped into solib return tramp\n");
6379 /* Only proceed through if we know where it's going. */
6382 /* And put the step-breakpoint there and go until there. */
6383 symtab_and_line sr_sal
;
6384 sr_sal
.pc
= real_stop_pc
;
6385 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6386 sr_sal
.pspace
= get_frame_program_space (frame
);
6388 /* Do not specify what the fp should be when we stop since
6389 on some machines the prologue is where the new fp value
6391 insert_step_resume_breakpoint_at_sal (gdbarch
,
6392 sr_sal
, null_frame_id
);
6394 /* Restart without fiddling with the step ranges or
6401 /* Check for subroutine calls. The check for the current frame
6402 equalling the step ID is not necessary - the check of the
6403 previous frame's ID is sufficient - but it is a common case and
6404 cheaper than checking the previous frame's ID.
6406 NOTE: frame_id_eq will never report two invalid frame IDs as
6407 being equal, so to get into this block, both the current and
6408 previous frame must have valid frame IDs. */
6409 /* The outer_frame_id check is a heuristic to detect stepping
6410 through startup code. If we step over an instruction which
6411 sets the stack pointer from an invalid value to a valid value,
6412 we may detect that as a subroutine call from the mythical
6413 "outermost" function. This could be fixed by marking
6414 outermost frames as !stack_p,code_p,special_p. Then the
6415 initial outermost frame, before sp was valid, would
6416 have code_addr == &_start. See the comment in frame_id_eq
6418 if (!frame_id_eq (get_stack_frame_id (frame
),
6419 ecs
->event_thread
->control
.step_stack_frame_id
)
6420 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6421 ecs
->event_thread
->control
.step_stack_frame_id
)
6422 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
6424 || (ecs
->event_thread
->control
.step_start_function
6425 != find_pc_function (ecs
->event_thread
->suspend
.stop_pc
)))))
6427 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6428 CORE_ADDR real_stop_pc
;
6431 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
6433 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
6435 /* I presume that step_over_calls is only 0 when we're
6436 supposed to be stepping at the assembly language level
6437 ("stepi"). Just stop. */
6438 /* And this works the same backward as frontward. MVS */
6439 end_stepping_range (ecs
);
6443 /* Reverse stepping through solib trampolines. */
6445 if (execution_direction
== EXEC_REVERSE
6446 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6447 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6448 || (ecs
->stop_func_start
== 0
6449 && in_solib_dynsym_resolve_code (stop_pc
))))
6451 /* Any solib trampoline code can be handled in reverse
6452 by simply continuing to single-step. We have already
6453 executed the solib function (backwards), and a few
6454 steps will take us back through the trampoline to the
6460 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6462 /* We're doing a "next".
6464 Normal (forward) execution: set a breakpoint at the
6465 callee's return address (the address at which the caller
6468 Reverse (backward) execution. set the step-resume
6469 breakpoint at the start of the function that we just
6470 stepped into (backwards), and continue to there. When we
6471 get there, we'll need to single-step back to the caller. */
6473 if (execution_direction
== EXEC_REVERSE
)
6475 /* If we're already at the start of the function, we've either
6476 just stepped backward into a single instruction function,
6477 or stepped back out of a signal handler to the first instruction
6478 of the function. Just keep going, which will single-step back
6480 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
6482 /* Normal function call return (static or dynamic). */
6483 symtab_and_line sr_sal
;
6484 sr_sal
.pc
= ecs
->stop_func_start
;
6485 sr_sal
.pspace
= get_frame_program_space (frame
);
6486 insert_step_resume_breakpoint_at_sal (gdbarch
,
6487 sr_sal
, null_frame_id
);
6491 insert_step_resume_breakpoint_at_caller (frame
);
6497 /* If we are in a function call trampoline (a stub between the
6498 calling routine and the real function), locate the real
6499 function. That's what tells us (a) whether we want to step
6500 into it at all, and (b) what prologue we want to run to the
6501 end of, if we do step into it. */
6502 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
6503 if (real_stop_pc
== 0)
6504 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6505 if (real_stop_pc
!= 0)
6506 ecs
->stop_func_start
= real_stop_pc
;
6508 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
6510 symtab_and_line sr_sal
;
6511 sr_sal
.pc
= ecs
->stop_func_start
;
6512 sr_sal
.pspace
= get_frame_program_space (frame
);
6514 insert_step_resume_breakpoint_at_sal (gdbarch
,
6515 sr_sal
, null_frame_id
);
6520 /* If we have line number information for the function we are
6521 thinking of stepping into and the function isn't on the skip
6524 If there are several symtabs at that PC (e.g. with include
6525 files), just want to know whether *any* of them have line
6526 numbers. find_pc_line handles this. */
6528 struct symtab_and_line tmp_sal
;
6530 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
6531 if (tmp_sal
.line
!= 0
6532 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
6535 if (execution_direction
== EXEC_REVERSE
)
6536 handle_step_into_function_backward (gdbarch
, ecs
);
6538 handle_step_into_function (gdbarch
, ecs
);
6543 /* If we have no line number and the step-stop-if-no-debug is
6544 set, we stop the step so that the user has a chance to switch
6545 in assembly mode. */
6546 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6547 && step_stop_if_no_debug
)
6549 end_stepping_range (ecs
);
6553 if (execution_direction
== EXEC_REVERSE
)
6555 /* If we're already at the start of the function, we've either just
6556 stepped backward into a single instruction function without line
6557 number info, or stepped back out of a signal handler to the first
6558 instruction of the function without line number info. Just keep
6559 going, which will single-step back to the caller. */
6560 if (ecs
->stop_func_start
!= stop_pc
)
6562 /* Set a breakpoint at callee's start address.
6563 From there we can step once and be back in the caller. */
6564 symtab_and_line sr_sal
;
6565 sr_sal
.pc
= ecs
->stop_func_start
;
6566 sr_sal
.pspace
= get_frame_program_space (frame
);
6567 insert_step_resume_breakpoint_at_sal (gdbarch
,
6568 sr_sal
, null_frame_id
);
6572 /* Set a breakpoint at callee's return address (the address
6573 at which the caller will resume). */
6574 insert_step_resume_breakpoint_at_caller (frame
);
6580 /* Reverse stepping through solib trampolines. */
6582 if (execution_direction
== EXEC_REVERSE
6583 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6585 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6587 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6588 || (ecs
->stop_func_start
== 0
6589 && in_solib_dynsym_resolve_code (stop_pc
)))
6591 /* Any solib trampoline code can be handled in reverse
6592 by simply continuing to single-step. We have already
6593 executed the solib function (backwards), and a few
6594 steps will take us back through the trampoline to the
6599 else if (in_solib_dynsym_resolve_code (stop_pc
))
6601 /* Stepped backward into the solib dynsym resolver.
6602 Set a breakpoint at its start and continue, then
6603 one more step will take us out. */
6604 symtab_and_line sr_sal
;
6605 sr_sal
.pc
= ecs
->stop_func_start
;
6606 sr_sal
.pspace
= get_frame_program_space (frame
);
6607 insert_step_resume_breakpoint_at_sal (gdbarch
,
6608 sr_sal
, null_frame_id
);
6614 stop_pc_sal
= find_pc_line (ecs
->event_thread
->suspend
.stop_pc
, 0);
6616 /* NOTE: tausq/2004-05-24: This if block used to be done before all
6617 the trampoline processing logic, however, there are some trampolines
6618 that have no names, so we should do trampoline handling first. */
6619 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6620 && ecs
->stop_func_name
== NULL
6621 && stop_pc_sal
.line
== 0)
6624 fprintf_unfiltered (gdb_stdlog
,
6625 "infrun: stepped into undebuggable function\n");
6627 /* The inferior just stepped into, or returned to, an
6628 undebuggable function (where there is no debugging information
6629 and no line number corresponding to the address where the
6630 inferior stopped). Since we want to skip this kind of code,
6631 we keep going until the inferior returns from this
6632 function - unless the user has asked us not to (via
6633 set step-mode) or we no longer know how to get back
6634 to the call site. */
6635 if (step_stop_if_no_debug
6636 || !frame_id_p (frame_unwind_caller_id (frame
)))
6638 /* If we have no line number and the step-stop-if-no-debug
6639 is set, we stop the step so that the user has a chance to
6640 switch in assembly mode. */
6641 end_stepping_range (ecs
);
6646 /* Set a breakpoint at callee's return address (the address
6647 at which the caller will resume). */
6648 insert_step_resume_breakpoint_at_caller (frame
);
6654 if (ecs
->event_thread
->control
.step_range_end
== 1)
6656 /* It is stepi or nexti. We always want to stop stepping after
6659 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
6660 end_stepping_range (ecs
);
6664 if (stop_pc_sal
.line
== 0)
6666 /* We have no line number information. That means to stop
6667 stepping (does this always happen right after one instruction,
6668 when we do "s" in a function with no line numbers,
6669 or can this happen as a result of a return or longjmp?). */
6671 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
6672 end_stepping_range (ecs
);
6676 /* Look for "calls" to inlined functions, part one. If the inline
6677 frame machinery detected some skipped call sites, we have entered
6678 a new inline function. */
6680 if (frame_id_eq (get_frame_id (get_current_frame ()),
6681 ecs
->event_thread
->control
.step_frame_id
)
6682 && inline_skipped_frames (ecs
->event_thread
))
6685 fprintf_unfiltered (gdb_stdlog
,
6686 "infrun: stepped into inlined function\n");
6688 symtab_and_line call_sal
= find_frame_sal (get_current_frame ());
6690 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
6692 /* For "step", we're going to stop. But if the call site
6693 for this inlined function is on the same source line as
6694 we were previously stepping, go down into the function
6695 first. Otherwise stop at the call site. */
6697 if (call_sal
.line
== ecs
->event_thread
->current_line
6698 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6699 step_into_inline_frame (ecs
->event_thread
);
6701 end_stepping_range (ecs
);
6706 /* For "next", we should stop at the call site if it is on a
6707 different source line. Otherwise continue through the
6708 inlined function. */
6709 if (call_sal
.line
== ecs
->event_thread
->current_line
6710 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6713 end_stepping_range (ecs
);
6718 /* Look for "calls" to inlined functions, part two. If we are still
6719 in the same real function we were stepping through, but we have
6720 to go further up to find the exact frame ID, we are stepping
6721 through a more inlined call beyond its call site. */
6723 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
6724 && !frame_id_eq (get_frame_id (get_current_frame ()),
6725 ecs
->event_thread
->control
.step_frame_id
)
6726 && stepped_in_from (get_current_frame (),
6727 ecs
->event_thread
->control
.step_frame_id
))
6730 fprintf_unfiltered (gdb_stdlog
,
6731 "infrun: stepping through inlined function\n");
6733 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6736 end_stepping_range (ecs
);
6740 if ((ecs
->event_thread
->suspend
.stop_pc
== stop_pc_sal
.pc
)
6741 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
6742 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
6744 /* We are at the start of a different line. So stop. Note that
6745 we don't stop if we step into the middle of a different line.
6746 That is said to make things like for (;;) statements work
6749 fprintf_unfiltered (gdb_stdlog
,
6750 "infrun: stepped to a different line\n");
6751 end_stepping_range (ecs
);
6755 /* We aren't done stepping.
6757 Optimize by setting the stepping range to the line.
6758 (We might not be in the original line, but if we entered a
6759 new line in mid-statement, we continue stepping. This makes
6760 things like for(;;) statements work better.) */
6762 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
6763 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
6764 ecs
->event_thread
->control
.may_range_step
= 1;
6765 set_step_info (frame
, stop_pc_sal
);
6768 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
6772 /* In all-stop mode, if we're currently stepping but have stopped in
6773 some other thread, we may need to switch back to the stepped
6774 thread. Returns true we set the inferior running, false if we left
6775 it stopped (and the event needs further processing). */
6778 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
6780 if (!target_is_non_stop_p ())
6782 struct thread_info
*stepping_thread
;
6784 /* If any thread is blocked on some internal breakpoint, and we
6785 simply need to step over that breakpoint to get it going
6786 again, do that first. */
6788 /* However, if we see an event for the stepping thread, then we
6789 know all other threads have been moved past their breakpoints
6790 already. Let the caller check whether the step is finished,
6791 etc., before deciding to move it past a breakpoint. */
6792 if (ecs
->event_thread
->control
.step_range_end
!= 0)
6795 /* Check if the current thread is blocked on an incomplete
6796 step-over, interrupted by a random signal. */
6797 if (ecs
->event_thread
->control
.trap_expected
6798 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
6802 fprintf_unfiltered (gdb_stdlog
,
6803 "infrun: need to finish step-over of [%s]\n",
6804 target_pid_to_str (ecs
->event_thread
->ptid
).c_str ());
6810 /* Check if the current thread is blocked by a single-step
6811 breakpoint of another thread. */
6812 if (ecs
->hit_singlestep_breakpoint
)
6816 fprintf_unfiltered (gdb_stdlog
,
6817 "infrun: need to step [%s] over single-step "
6819 target_pid_to_str (ecs
->ptid
).c_str ());
6825 /* If this thread needs yet another step-over (e.g., stepping
6826 through a delay slot), do it first before moving on to
6828 if (thread_still_needs_step_over (ecs
->event_thread
))
6832 fprintf_unfiltered (gdb_stdlog
,
6833 "infrun: thread [%s] still needs step-over\n",
6834 target_pid_to_str (ecs
->event_thread
->ptid
).c_str ());
6840 /* If scheduler locking applies even if not stepping, there's no
6841 need to walk over threads. Above we've checked whether the
6842 current thread is stepping. If some other thread not the
6843 event thread is stepping, then it must be that scheduler
6844 locking is not in effect. */
6845 if (schedlock_applies (ecs
->event_thread
))
6848 /* Otherwise, we no longer expect a trap in the current thread.
6849 Clear the trap_expected flag before switching back -- this is
6850 what keep_going does as well, if we call it. */
6851 ecs
->event_thread
->control
.trap_expected
= 0;
6853 /* Likewise, clear the signal if it should not be passed. */
6854 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
6855 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6857 /* Do all pending step-overs before actually proceeding with
6859 if (start_step_over ())
6861 prepare_to_wait (ecs
);
6865 /* Look for the stepping/nexting thread. */
6866 stepping_thread
= NULL
;
6868 for (thread_info
*tp
: all_non_exited_threads ())
6870 /* Ignore threads of processes the caller is not
6873 && tp
->ptid
.pid () != ecs
->ptid
.pid ())
6876 /* When stepping over a breakpoint, we lock all threads
6877 except the one that needs to move past the breakpoint.
6878 If a non-event thread has this set, the "incomplete
6879 step-over" check above should have caught it earlier. */
6880 if (tp
->control
.trap_expected
)
6882 internal_error (__FILE__
, __LINE__
,
6883 "[%s] has inconsistent state: "
6884 "trap_expected=%d\n",
6885 target_pid_to_str (tp
->ptid
).c_str (),
6886 tp
->control
.trap_expected
);
6889 /* Did we find the stepping thread? */
6890 if (tp
->control
.step_range_end
)
6892 /* Yep. There should only one though. */
6893 gdb_assert (stepping_thread
== NULL
);
6895 /* The event thread is handled at the top, before we
6897 gdb_assert (tp
!= ecs
->event_thread
);
6899 /* If some thread other than the event thread is
6900 stepping, then scheduler locking can't be in effect,
6901 otherwise we wouldn't have resumed the current event
6902 thread in the first place. */
6903 gdb_assert (!schedlock_applies (tp
));
6905 stepping_thread
= tp
;
6909 if (stepping_thread
!= NULL
)
6912 fprintf_unfiltered (gdb_stdlog
,
6913 "infrun: switching back to stepped thread\n");
6915 if (keep_going_stepped_thread (stepping_thread
))
6917 prepare_to_wait (ecs
);
6926 /* Set a previously stepped thread back to stepping. Returns true on
6927 success, false if the resume is not possible (e.g., the thread
6931 keep_going_stepped_thread (struct thread_info
*tp
)
6933 struct frame_info
*frame
;
6934 struct execution_control_state ecss
;
6935 struct execution_control_state
*ecs
= &ecss
;
6937 /* If the stepping thread exited, then don't try to switch back and
6938 resume it, which could fail in several different ways depending
6939 on the target. Instead, just keep going.
6941 We can find a stepping dead thread in the thread list in two
6944 - The target supports thread exit events, and when the target
6945 tries to delete the thread from the thread list, inferior_ptid
6946 pointed at the exiting thread. In such case, calling
6947 delete_thread does not really remove the thread from the list;
6948 instead, the thread is left listed, with 'exited' state.
6950 - The target's debug interface does not support thread exit
6951 events, and so we have no idea whatsoever if the previously
6952 stepping thread is still alive. For that reason, we need to
6953 synchronously query the target now. */
6955 if (tp
->state
== THREAD_EXITED
|| !target_thread_alive (tp
->ptid
))
6958 fprintf_unfiltered (gdb_stdlog
,
6959 "infrun: not resuming previously "
6960 "stepped thread, it has vanished\n");
6967 fprintf_unfiltered (gdb_stdlog
,
6968 "infrun: resuming previously stepped thread\n");
6970 reset_ecs (ecs
, tp
);
6971 switch_to_thread (tp
);
6973 tp
->suspend
.stop_pc
= regcache_read_pc (get_thread_regcache (tp
));
6974 frame
= get_current_frame ();
6976 /* If the PC of the thread we were trying to single-step has
6977 changed, then that thread has trapped or been signaled, but the
6978 event has not been reported to GDB yet. Re-poll the target
6979 looking for this particular thread's event (i.e. temporarily
6980 enable schedlock) by:
6982 - setting a break at the current PC
6983 - resuming that particular thread, only (by setting trap
6986 This prevents us continuously moving the single-step breakpoint
6987 forward, one instruction at a time, overstepping. */
6989 if (tp
->suspend
.stop_pc
!= tp
->prev_pc
)
6994 fprintf_unfiltered (gdb_stdlog
,
6995 "infrun: expected thread advanced also (%s -> %s)\n",
6996 paddress (target_gdbarch (), tp
->prev_pc
),
6997 paddress (target_gdbarch (), tp
->suspend
.stop_pc
));
6999 /* Clear the info of the previous step-over, as it's no longer
7000 valid (if the thread was trying to step over a breakpoint, it
7001 has already succeeded). It's what keep_going would do too,
7002 if we called it. Do this before trying to insert the sss
7003 breakpoint, otherwise if we were previously trying to step
7004 over this exact address in another thread, the breakpoint is
7006 clear_step_over_info ();
7007 tp
->control
.trap_expected
= 0;
7009 insert_single_step_breakpoint (get_frame_arch (frame
),
7010 get_frame_address_space (frame
),
7011 tp
->suspend
.stop_pc
);
7014 resume_ptid
= internal_resume_ptid (tp
->control
.stepping_command
);
7015 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
7020 fprintf_unfiltered (gdb_stdlog
,
7021 "infrun: expected thread still hasn't advanced\n");
7023 keep_going_pass_signal (ecs
);
7028 /* Is thread TP in the middle of (software or hardware)
7029 single-stepping? (Note the result of this function must never be
7030 passed directly as target_resume's STEP parameter.) */
7033 currently_stepping (struct thread_info
*tp
)
7035 return ((tp
->control
.step_range_end
7036 && tp
->control
.step_resume_breakpoint
== NULL
)
7037 || tp
->control
.trap_expected
7038 || tp
->stepped_breakpoint
7039 || bpstat_should_step ());
7042 /* Inferior has stepped into a subroutine call with source code that
7043 we should not step over. Do step to the first line of code in
7047 handle_step_into_function (struct gdbarch
*gdbarch
,
7048 struct execution_control_state
*ecs
)
7050 fill_in_stop_func (gdbarch
, ecs
);
7052 compunit_symtab
*cust
7053 = find_pc_compunit_symtab (ecs
->event_thread
->suspend
.stop_pc
);
7054 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7055 ecs
->stop_func_start
7056 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7058 symtab_and_line stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7059 /* Use the step_resume_break to step until the end of the prologue,
7060 even if that involves jumps (as it seems to on the vax under
7062 /* If the prologue ends in the middle of a source line, continue to
7063 the end of that source line (if it is still within the function).
7064 Otherwise, just go to end of prologue. */
7065 if (stop_func_sal
.end
7066 && stop_func_sal
.pc
!= ecs
->stop_func_start
7067 && stop_func_sal
.end
< ecs
->stop_func_end
)
7068 ecs
->stop_func_start
= stop_func_sal
.end
;
7070 /* Architectures which require breakpoint adjustment might not be able
7071 to place a breakpoint at the computed address. If so, the test
7072 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7073 ecs->stop_func_start to an address at which a breakpoint may be
7074 legitimately placed.
7076 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7077 made, GDB will enter an infinite loop when stepping through
7078 optimized code consisting of VLIW instructions which contain
7079 subinstructions corresponding to different source lines. On
7080 FR-V, it's not permitted to place a breakpoint on any but the
7081 first subinstruction of a VLIW instruction. When a breakpoint is
7082 set, GDB will adjust the breakpoint address to the beginning of
7083 the VLIW instruction. Thus, we need to make the corresponding
7084 adjustment here when computing the stop address. */
7086 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
7088 ecs
->stop_func_start
7089 = gdbarch_adjust_breakpoint_address (gdbarch
,
7090 ecs
->stop_func_start
);
7093 if (ecs
->stop_func_start
== ecs
->event_thread
->suspend
.stop_pc
)
7095 /* We are already there: stop now. */
7096 end_stepping_range (ecs
);
7101 /* Put the step-breakpoint there and go until there. */
7102 symtab_and_line sr_sal
;
7103 sr_sal
.pc
= ecs
->stop_func_start
;
7104 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
7105 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
7107 /* Do not specify what the fp should be when we stop since on
7108 some machines the prologue is where the new fp value is
7110 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
7112 /* And make sure stepping stops right away then. */
7113 ecs
->event_thread
->control
.step_range_end
7114 = ecs
->event_thread
->control
.step_range_start
;
7119 /* Inferior has stepped backward into a subroutine call with source
7120 code that we should not step over. Do step to the beginning of the
7121 last line of code in it. */
7124 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
7125 struct execution_control_state
*ecs
)
7127 struct compunit_symtab
*cust
;
7128 struct symtab_and_line stop_func_sal
;
7130 fill_in_stop_func (gdbarch
, ecs
);
7132 cust
= find_pc_compunit_symtab (ecs
->event_thread
->suspend
.stop_pc
);
7133 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7134 ecs
->stop_func_start
7135 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7137 stop_func_sal
= find_pc_line (ecs
->event_thread
->suspend
.stop_pc
, 0);
7139 /* OK, we're just going to keep stepping here. */
7140 if (stop_func_sal
.pc
== ecs
->event_thread
->suspend
.stop_pc
)
7142 /* We're there already. Just stop stepping now. */
7143 end_stepping_range (ecs
);
7147 /* Else just reset the step range and keep going.
7148 No step-resume breakpoint, they don't work for
7149 epilogues, which can have multiple entry paths. */
7150 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
7151 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
7157 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7158 This is used to both functions and to skip over code. */
7161 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
7162 struct symtab_and_line sr_sal
,
7163 struct frame_id sr_id
,
7164 enum bptype sr_type
)
7166 /* There should never be more than one step-resume or longjmp-resume
7167 breakpoint per thread, so we should never be setting a new
7168 step_resume_breakpoint when one is already active. */
7169 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
7170 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
7173 fprintf_unfiltered (gdb_stdlog
,
7174 "infrun: inserting step-resume breakpoint at %s\n",
7175 paddress (gdbarch
, sr_sal
.pc
));
7177 inferior_thread ()->control
.step_resume_breakpoint
7178 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
).release ();
7182 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
7183 struct symtab_and_line sr_sal
,
7184 struct frame_id sr_id
)
7186 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
7191 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7192 This is used to skip a potential signal handler.
7194 This is called with the interrupted function's frame. The signal
7195 handler, when it returns, will resume the interrupted function at
7199 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
7201 gdb_assert (return_frame
!= NULL
);
7203 struct gdbarch
*gdbarch
= get_frame_arch (return_frame
);
7205 symtab_and_line sr_sal
;
7206 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
7207 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7208 sr_sal
.pspace
= get_frame_program_space (return_frame
);
7210 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
7211 get_stack_frame_id (return_frame
),
7215 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7216 is used to skip a function after stepping into it (for "next" or if
7217 the called function has no debugging information).
7219 The current function has almost always been reached by single
7220 stepping a call or return instruction. NEXT_FRAME belongs to the
7221 current function, and the breakpoint will be set at the caller's
7224 This is a separate function rather than reusing
7225 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7226 get_prev_frame, which may stop prematurely (see the implementation
7227 of frame_unwind_caller_id for an example). */
7230 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
7232 /* We shouldn't have gotten here if we don't know where the call site
7234 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
7236 struct gdbarch
*gdbarch
= frame_unwind_caller_arch (next_frame
);
7238 symtab_and_line sr_sal
;
7239 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
7240 frame_unwind_caller_pc (next_frame
));
7241 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7242 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
7244 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
7245 frame_unwind_caller_id (next_frame
));
7248 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7249 new breakpoint at the target of a jmp_buf. The handling of
7250 longjmp-resume uses the same mechanisms used for handling
7251 "step-resume" breakpoints. */
7254 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
7256 /* There should never be more than one longjmp-resume breakpoint per
7257 thread, so we should never be setting a new
7258 longjmp_resume_breakpoint when one is already active. */
7259 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
7262 fprintf_unfiltered (gdb_stdlog
,
7263 "infrun: inserting longjmp-resume breakpoint at %s\n",
7264 paddress (gdbarch
, pc
));
7266 inferior_thread ()->control
.exception_resume_breakpoint
=
7267 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
).release ();
7270 /* Insert an exception resume breakpoint. TP is the thread throwing
7271 the exception. The block B is the block of the unwinder debug hook
7272 function. FRAME is the frame corresponding to the call to this
7273 function. SYM is the symbol of the function argument holding the
7274 target PC of the exception. */
7277 insert_exception_resume_breakpoint (struct thread_info
*tp
,
7278 const struct block
*b
,
7279 struct frame_info
*frame
,
7284 struct block_symbol vsym
;
7285 struct value
*value
;
7287 struct breakpoint
*bp
;
7289 vsym
= lookup_symbol_search_name (sym
->search_name (),
7291 value
= read_var_value (vsym
.symbol
, vsym
.block
, frame
);
7292 /* If the value was optimized out, revert to the old behavior. */
7293 if (! value_optimized_out (value
))
7295 handler
= value_as_address (value
);
7298 fprintf_unfiltered (gdb_stdlog
,
7299 "infrun: exception resume at %lx\n",
7300 (unsigned long) handler
);
7302 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7304 bp_exception_resume
).release ();
7306 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7309 bp
->thread
= tp
->global_num
;
7310 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7313 catch (const gdb_exception_error
&e
)
7315 /* We want to ignore errors here. */
7319 /* A helper for check_exception_resume that sets an
7320 exception-breakpoint based on a SystemTap probe. */
7323 insert_exception_resume_from_probe (struct thread_info
*tp
,
7324 const struct bound_probe
*probe
,
7325 struct frame_info
*frame
)
7327 struct value
*arg_value
;
7329 struct breakpoint
*bp
;
7331 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
7335 handler
= value_as_address (arg_value
);
7338 fprintf_unfiltered (gdb_stdlog
,
7339 "infrun: exception resume at %s\n",
7340 paddress (get_objfile_arch (probe
->objfile
),
7343 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7344 handler
, bp_exception_resume
).release ();
7345 bp
->thread
= tp
->global_num
;
7346 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7349 /* This is called when an exception has been intercepted. Check to
7350 see whether the exception's destination is of interest, and if so,
7351 set an exception resume breakpoint there. */
7354 check_exception_resume (struct execution_control_state
*ecs
,
7355 struct frame_info
*frame
)
7357 struct bound_probe probe
;
7358 struct symbol
*func
;
7360 /* First see if this exception unwinding breakpoint was set via a
7361 SystemTap probe point. If so, the probe has two arguments: the
7362 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7363 set a breakpoint there. */
7364 probe
= find_probe_by_pc (get_frame_pc (frame
));
7367 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
7371 func
= get_frame_function (frame
);
7377 const struct block
*b
;
7378 struct block_iterator iter
;
7382 /* The exception breakpoint is a thread-specific breakpoint on
7383 the unwinder's debug hook, declared as:
7385 void _Unwind_DebugHook (void *cfa, void *handler);
7387 The CFA argument indicates the frame to which control is
7388 about to be transferred. HANDLER is the destination PC.
7390 We ignore the CFA and set a temporary breakpoint at HANDLER.
7391 This is not extremely efficient but it avoids issues in gdb
7392 with computing the DWARF CFA, and it also works even in weird
7393 cases such as throwing an exception from inside a signal
7396 b
= SYMBOL_BLOCK_VALUE (func
);
7397 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
7399 if (!SYMBOL_IS_ARGUMENT (sym
))
7406 insert_exception_resume_breakpoint (ecs
->event_thread
,
7412 catch (const gdb_exception_error
&e
)
7418 stop_waiting (struct execution_control_state
*ecs
)
7421 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
7423 /* Let callers know we don't want to wait for the inferior anymore. */
7424 ecs
->wait_some_more
= 0;
7426 /* If all-stop, but the target is always in non-stop mode, stop all
7427 threads now that we're presenting the stop to the user. */
7428 if (!non_stop
&& target_is_non_stop_p ())
7429 stop_all_threads ();
7432 /* Like keep_going, but passes the signal to the inferior, even if the
7433 signal is set to nopass. */
7436 keep_going_pass_signal (struct execution_control_state
*ecs
)
7438 gdb_assert (ecs
->event_thread
->ptid
== inferior_ptid
);
7439 gdb_assert (!ecs
->event_thread
->resumed
);
7441 /* Save the pc before execution, to compare with pc after stop. */
7442 ecs
->event_thread
->prev_pc
7443 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
7445 if (ecs
->event_thread
->control
.trap_expected
)
7447 struct thread_info
*tp
= ecs
->event_thread
;
7450 fprintf_unfiltered (gdb_stdlog
,
7451 "infrun: %s has trap_expected set, "
7452 "resuming to collect trap\n",
7453 target_pid_to_str (tp
->ptid
).c_str ());
7455 /* We haven't yet gotten our trap, and either: intercepted a
7456 non-signal event (e.g., a fork); or took a signal which we
7457 are supposed to pass through to the inferior. Simply
7459 resume (ecs
->event_thread
->suspend
.stop_signal
);
7461 else if (step_over_info_valid_p ())
7463 /* Another thread is stepping over a breakpoint in-line. If
7464 this thread needs a step-over too, queue the request. In
7465 either case, this resume must be deferred for later. */
7466 struct thread_info
*tp
= ecs
->event_thread
;
7468 if (ecs
->hit_singlestep_breakpoint
7469 || thread_still_needs_step_over (tp
))
7472 fprintf_unfiltered (gdb_stdlog
,
7473 "infrun: step-over already in progress: "
7474 "step-over for %s deferred\n",
7475 target_pid_to_str (tp
->ptid
).c_str ());
7476 thread_step_over_chain_enqueue (tp
);
7481 fprintf_unfiltered (gdb_stdlog
,
7482 "infrun: step-over in progress: "
7483 "resume of %s deferred\n",
7484 target_pid_to_str (tp
->ptid
).c_str ());
7489 struct regcache
*regcache
= get_current_regcache ();
7492 step_over_what step_what
;
7494 /* Either the trap was not expected, but we are continuing
7495 anyway (if we got a signal, the user asked it be passed to
7498 We got our expected trap, but decided we should resume from
7501 We're going to run this baby now!
7503 Note that insert_breakpoints won't try to re-insert
7504 already inserted breakpoints. Therefore, we don't
7505 care if breakpoints were already inserted, or not. */
7507 /* If we need to step over a breakpoint, and we're not using
7508 displaced stepping to do so, insert all breakpoints
7509 (watchpoints, etc.) but the one we're stepping over, step one
7510 instruction, and then re-insert the breakpoint when that step
7513 step_what
= thread_still_needs_step_over (ecs
->event_thread
);
7515 remove_bp
= (ecs
->hit_singlestep_breakpoint
7516 || (step_what
& STEP_OVER_BREAKPOINT
));
7517 remove_wps
= (step_what
& STEP_OVER_WATCHPOINT
);
7519 /* We can't use displaced stepping if we need to step past a
7520 watchpoint. The instruction copied to the scratch pad would
7521 still trigger the watchpoint. */
7523 && (remove_wps
|| !use_displaced_stepping (ecs
->event_thread
)))
7525 set_step_over_info (regcache
->aspace (),
7526 regcache_read_pc (regcache
), remove_wps
,
7527 ecs
->event_thread
->global_num
);
7529 else if (remove_wps
)
7530 set_step_over_info (NULL
, 0, remove_wps
, -1);
7532 /* If we now need to do an in-line step-over, we need to stop
7533 all other threads. Note this must be done before
7534 insert_breakpoints below, because that removes the breakpoint
7535 we're about to step over, otherwise other threads could miss
7537 if (step_over_info_valid_p () && target_is_non_stop_p ())
7538 stop_all_threads ();
7540 /* Stop stepping if inserting breakpoints fails. */
7543 insert_breakpoints ();
7545 catch (const gdb_exception_error
&e
)
7547 exception_print (gdb_stderr
, e
);
7549 clear_step_over_info ();
7553 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
7555 resume (ecs
->event_thread
->suspend
.stop_signal
);
7558 prepare_to_wait (ecs
);
7561 /* Called when we should continue running the inferior, because the
7562 current event doesn't cause a user visible stop. This does the
7563 resuming part; waiting for the next event is done elsewhere. */
7566 keep_going (struct execution_control_state
*ecs
)
7568 if (ecs
->event_thread
->control
.trap_expected
7569 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
7570 ecs
->event_thread
->control
.trap_expected
= 0;
7572 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7573 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7574 keep_going_pass_signal (ecs
);
7577 /* This function normally comes after a resume, before
7578 handle_inferior_event exits. It takes care of any last bits of
7579 housekeeping, and sets the all-important wait_some_more flag. */
7582 prepare_to_wait (struct execution_control_state
*ecs
)
7585 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
7587 ecs
->wait_some_more
= 1;
7589 if (!target_is_async_p ())
7590 mark_infrun_async_event_handler ();
7593 /* We are done with the step range of a step/next/si/ni command.
7594 Called once for each n of a "step n" operation. */
7597 end_stepping_range (struct execution_control_state
*ecs
)
7599 ecs
->event_thread
->control
.stop_step
= 1;
7603 /* Several print_*_reason functions to print why the inferior has stopped.
7604 We always print something when the inferior exits, or receives a signal.
7605 The rest of the cases are dealt with later on in normal_stop and
7606 print_it_typical. Ideally there should be a call to one of these
7607 print_*_reason functions functions from handle_inferior_event each time
7608 stop_waiting is called.
7610 Note that we don't call these directly, instead we delegate that to
7611 the interpreters, through observers. Interpreters then call these
7612 with whatever uiout is right. */
7615 print_end_stepping_range_reason (struct ui_out
*uiout
)
7617 /* For CLI-like interpreters, print nothing. */
7619 if (uiout
->is_mi_like_p ())
7621 uiout
->field_string ("reason",
7622 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
7627 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7629 annotate_signalled ();
7630 if (uiout
->is_mi_like_p ())
7632 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
7633 uiout
->text ("\nProgram terminated with signal ");
7634 annotate_signal_name ();
7635 uiout
->field_string ("signal-name",
7636 gdb_signal_to_name (siggnal
));
7637 annotate_signal_name_end ();
7639 annotate_signal_string ();
7640 uiout
->field_string ("signal-meaning",
7641 gdb_signal_to_string (siggnal
));
7642 annotate_signal_string_end ();
7643 uiout
->text (".\n");
7644 uiout
->text ("The program no longer exists.\n");
7648 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
7650 struct inferior
*inf
= current_inferior ();
7651 std::string pidstr
= target_pid_to_str (ptid_t (inf
->pid
));
7653 annotate_exited (exitstatus
);
7656 if (uiout
->is_mi_like_p ())
7657 uiout
->field_string ("reason", async_reason_lookup (EXEC_ASYNC_EXITED
));
7658 std::string exit_code_str
7659 = string_printf ("0%o", (unsigned int) exitstatus
);
7660 uiout
->message ("[Inferior %s (%s) exited with code %pF]\n",
7661 plongest (inf
->num
), pidstr
.c_str (),
7662 string_field ("exit-code", exit_code_str
.c_str ()));
7666 if (uiout
->is_mi_like_p ())
7668 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
7669 uiout
->message ("[Inferior %s (%s) exited normally]\n",
7670 plongest (inf
->num
), pidstr
.c_str ());
7674 /* Some targets/architectures can do extra processing/display of
7675 segmentation faults. E.g., Intel MPX boundary faults.
7676 Call the architecture dependent function to handle the fault. */
7679 handle_segmentation_fault (struct ui_out
*uiout
)
7681 struct regcache
*regcache
= get_current_regcache ();
7682 struct gdbarch
*gdbarch
= regcache
->arch ();
7684 if (gdbarch_handle_segmentation_fault_p (gdbarch
))
7685 gdbarch_handle_segmentation_fault (gdbarch
, uiout
);
7689 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7691 struct thread_info
*thr
= inferior_thread ();
7695 if (uiout
->is_mi_like_p ())
7697 else if (show_thread_that_caused_stop ())
7701 uiout
->text ("\nThread ");
7702 uiout
->field_string ("thread-id", print_thread_id (thr
));
7704 name
= thr
->name
!= NULL
? thr
->name
: target_thread_name (thr
);
7707 uiout
->text (" \"");
7708 uiout
->field_string ("name", name
);
7713 uiout
->text ("\nProgram");
7715 if (siggnal
== GDB_SIGNAL_0
&& !uiout
->is_mi_like_p ())
7716 uiout
->text (" stopped");
7719 uiout
->text (" received signal ");
7720 annotate_signal_name ();
7721 if (uiout
->is_mi_like_p ())
7723 ("reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
7724 uiout
->field_string ("signal-name", gdb_signal_to_name (siggnal
));
7725 annotate_signal_name_end ();
7727 annotate_signal_string ();
7728 uiout
->field_string ("signal-meaning", gdb_signal_to_string (siggnal
));
7730 if (siggnal
== GDB_SIGNAL_SEGV
)
7731 handle_segmentation_fault (uiout
);
7733 annotate_signal_string_end ();
7735 uiout
->text (".\n");
7739 print_no_history_reason (struct ui_out
*uiout
)
7741 uiout
->text ("\nNo more reverse-execution history.\n");
7744 /* Print current location without a level number, if we have changed
7745 functions or hit a breakpoint. Print source line if we have one.
7746 bpstat_print contains the logic deciding in detail what to print,
7747 based on the event(s) that just occurred. */
7750 print_stop_location (struct target_waitstatus
*ws
)
7753 enum print_what source_flag
;
7754 int do_frame_printing
= 1;
7755 struct thread_info
*tp
= inferior_thread ();
7757 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
7761 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
7762 should) carry around the function and does (or should) use
7763 that when doing a frame comparison. */
7764 if (tp
->control
.stop_step
7765 && frame_id_eq (tp
->control
.step_frame_id
,
7766 get_frame_id (get_current_frame ()))
7767 && (tp
->control
.step_start_function
7768 == find_pc_function (tp
->suspend
.stop_pc
)))
7770 /* Finished step, just print source line. */
7771 source_flag
= SRC_LINE
;
7775 /* Print location and source line. */
7776 source_flag
= SRC_AND_LOC
;
7779 case PRINT_SRC_AND_LOC
:
7780 /* Print location and source line. */
7781 source_flag
= SRC_AND_LOC
;
7783 case PRINT_SRC_ONLY
:
7784 source_flag
= SRC_LINE
;
7787 /* Something bogus. */
7788 source_flag
= SRC_LINE
;
7789 do_frame_printing
= 0;
7792 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
7795 /* The behavior of this routine with respect to the source
7797 SRC_LINE: Print only source line
7798 LOCATION: Print only location
7799 SRC_AND_LOC: Print location and source line. */
7800 if (do_frame_printing
)
7801 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
7807 print_stop_event (struct ui_out
*uiout
, bool displays
)
7809 struct target_waitstatus last
;
7811 struct thread_info
*tp
;
7813 get_last_target_status (&last_ptid
, &last
);
7816 scoped_restore save_uiout
= make_scoped_restore (¤t_uiout
, uiout
);
7818 print_stop_location (&last
);
7820 /* Display the auto-display expressions. */
7825 tp
= inferior_thread ();
7826 if (tp
->thread_fsm
!= NULL
7827 && tp
->thread_fsm
->finished_p ())
7829 struct return_value_info
*rv
;
7831 rv
= tp
->thread_fsm
->return_value ();
7833 print_return_value (uiout
, rv
);
7840 maybe_remove_breakpoints (void)
7842 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
7844 if (remove_breakpoints ())
7846 target_terminal::ours_for_output ();
7847 printf_filtered (_("Cannot remove breakpoints because "
7848 "program is no longer writable.\nFurther "
7849 "execution is probably impossible.\n"));
7854 /* The execution context that just caused a normal stop. */
7861 DISABLE_COPY_AND_ASSIGN (stop_context
);
7863 bool changed () const;
7868 /* The event PTID. */
7872 /* If stopp for a thread event, this is the thread that caused the
7874 struct thread_info
*thread
;
7876 /* The inferior that caused the stop. */
7880 /* Initializes a new stop context. If stopped for a thread event, this
7881 takes a strong reference to the thread. */
7883 stop_context::stop_context ()
7885 stop_id
= get_stop_id ();
7886 ptid
= inferior_ptid
;
7887 inf_num
= current_inferior ()->num
;
7889 if (inferior_ptid
!= null_ptid
)
7891 /* Take a strong reference so that the thread can't be deleted
7893 thread
= inferior_thread ();
7900 /* Release a stop context previously created with save_stop_context.
7901 Releases the strong reference to the thread as well. */
7903 stop_context::~stop_context ()
7909 /* Return true if the current context no longer matches the saved stop
7913 stop_context::changed () const
7915 if (ptid
!= inferior_ptid
)
7917 if (inf_num
!= current_inferior ()->num
)
7919 if (thread
!= NULL
&& thread
->state
!= THREAD_STOPPED
)
7921 if (get_stop_id () != stop_id
)
7931 struct target_waitstatus last
;
7934 get_last_target_status (&last_ptid
, &last
);
7938 /* If an exception is thrown from this point on, make sure to
7939 propagate GDB's knowledge of the executing state to the
7940 frontend/user running state. A QUIT is an easy exception to see
7941 here, so do this before any filtered output. */
7943 gdb::optional
<scoped_finish_thread_state
> maybe_finish_thread_state
;
7946 maybe_finish_thread_state
.emplace (minus_one_ptid
);
7947 else if (last
.kind
== TARGET_WAITKIND_SIGNALLED
7948 || last
.kind
== TARGET_WAITKIND_EXITED
)
7950 /* On some targets, we may still have live threads in the
7951 inferior when we get a process exit event. E.g., for
7952 "checkpoint", when the current checkpoint/fork exits,
7953 linux-fork.c automatically switches to another fork from
7954 within target_mourn_inferior. */
7955 if (inferior_ptid
!= null_ptid
)
7956 maybe_finish_thread_state
.emplace (ptid_t (inferior_ptid
.pid ()));
7958 else if (last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
7959 maybe_finish_thread_state
.emplace (inferior_ptid
);
7961 /* As we're presenting a stop, and potentially removing breakpoints,
7962 update the thread list so we can tell whether there are threads
7963 running on the target. With target remote, for example, we can
7964 only learn about new threads when we explicitly update the thread
7965 list. Do this before notifying the interpreters about signal
7966 stops, end of stepping ranges, etc., so that the "new thread"
7967 output is emitted before e.g., "Program received signal FOO",
7968 instead of after. */
7969 update_thread_list ();
7971 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
7972 gdb::observers::signal_received
.notify (inferior_thread ()->suspend
.stop_signal
);
7974 /* As with the notification of thread events, we want to delay
7975 notifying the user that we've switched thread context until
7976 the inferior actually stops.
7978 There's no point in saying anything if the inferior has exited.
7979 Note that SIGNALLED here means "exited with a signal", not
7980 "received a signal".
7982 Also skip saying anything in non-stop mode. In that mode, as we
7983 don't want GDB to switch threads behind the user's back, to avoid
7984 races where the user is typing a command to apply to thread x,
7985 but GDB switches to thread y before the user finishes entering
7986 the command, fetch_inferior_event installs a cleanup to restore
7987 the current thread back to the thread the user had selected right
7988 after this event is handled, so we're not really switching, only
7989 informing of a stop. */
7991 && previous_inferior_ptid
!= inferior_ptid
7992 && target_has_execution
7993 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
7994 && last
.kind
!= TARGET_WAITKIND_EXITED
7995 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
7997 SWITCH_THRU_ALL_UIS ()
7999 target_terminal::ours_for_output ();
8000 printf_filtered (_("[Switching to %s]\n"),
8001 target_pid_to_str (inferior_ptid
).c_str ());
8002 annotate_thread_changed ();
8004 previous_inferior_ptid
= inferior_ptid
;
8007 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
8009 SWITCH_THRU_ALL_UIS ()
8010 if (current_ui
->prompt_state
== PROMPT_BLOCKED
)
8012 target_terminal::ours_for_output ();
8013 printf_filtered (_("No unwaited-for children left.\n"));
8017 /* Note: this depends on the update_thread_list call above. */
8018 maybe_remove_breakpoints ();
8020 /* If an auto-display called a function and that got a signal,
8021 delete that auto-display to avoid an infinite recursion. */
8023 if (stopped_by_random_signal
)
8024 disable_current_display ();
8026 SWITCH_THRU_ALL_UIS ()
8028 async_enable_stdin ();
8031 /* Let the user/frontend see the threads as stopped. */
8032 maybe_finish_thread_state
.reset ();
8034 /* Select innermost stack frame - i.e., current frame is frame 0,
8035 and current location is based on that. Handle the case where the
8036 dummy call is returning after being stopped. E.g. the dummy call
8037 previously hit a breakpoint. (If the dummy call returns
8038 normally, we won't reach here.) Do this before the stop hook is
8039 run, so that it doesn't get to see the temporary dummy frame,
8040 which is not where we'll present the stop. */
8041 if (has_stack_frames ())
8043 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
8045 /* Pop the empty frame that contains the stack dummy. This
8046 also restores inferior state prior to the call (struct
8047 infcall_suspend_state). */
8048 struct frame_info
*frame
= get_current_frame ();
8050 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
8052 /* frame_pop calls reinit_frame_cache as the last thing it
8053 does which means there's now no selected frame. */
8056 select_frame (get_current_frame ());
8058 /* Set the current source location. */
8059 set_current_sal_from_frame (get_current_frame ());
8062 /* Look up the hook_stop and run it (CLI internally handles problem
8063 of stop_command's pre-hook not existing). */
8064 if (stop_command
!= NULL
)
8066 stop_context saved_context
;
8070 execute_cmd_pre_hook (stop_command
);
8072 catch (const gdb_exception
&ex
)
8074 exception_fprintf (gdb_stderr
, ex
,
8075 "Error while running hook_stop:\n");
8078 /* If the stop hook resumes the target, then there's no point in
8079 trying to notify about the previous stop; its context is
8080 gone. Likewise if the command switches thread or inferior --
8081 the observers would print a stop for the wrong
8083 if (saved_context
.changed ())
8087 /* Notify observers about the stop. This is where the interpreters
8088 print the stop event. */
8089 if (inferior_ptid
!= null_ptid
)
8090 gdb::observers::normal_stop
.notify (inferior_thread ()->control
.stop_bpstat
,
8093 gdb::observers::normal_stop
.notify (NULL
, stop_print_frame
);
8095 annotate_stopped ();
8097 if (target_has_execution
)
8099 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
8100 && last
.kind
!= TARGET_WAITKIND_EXITED
8101 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8102 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8103 Delete any breakpoint that is to be deleted at the next stop. */
8104 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
8107 /* Try to get rid of automatically added inferiors that are no
8108 longer needed. Keeping those around slows down things linearly.
8109 Note that this never removes the current inferior. */
8116 signal_stop_state (int signo
)
8118 return signal_stop
[signo
];
8122 signal_print_state (int signo
)
8124 return signal_print
[signo
];
8128 signal_pass_state (int signo
)
8130 return signal_program
[signo
];
8134 signal_cache_update (int signo
)
8138 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
8139 signal_cache_update (signo
);
8144 signal_pass
[signo
] = (signal_stop
[signo
] == 0
8145 && signal_print
[signo
] == 0
8146 && signal_program
[signo
] == 1
8147 && signal_catch
[signo
] == 0);
8151 signal_stop_update (int signo
, int state
)
8153 int ret
= signal_stop
[signo
];
8155 signal_stop
[signo
] = state
;
8156 signal_cache_update (signo
);
8161 signal_print_update (int signo
, int state
)
8163 int ret
= signal_print
[signo
];
8165 signal_print
[signo
] = state
;
8166 signal_cache_update (signo
);
8171 signal_pass_update (int signo
, int state
)
8173 int ret
= signal_program
[signo
];
8175 signal_program
[signo
] = state
;
8176 signal_cache_update (signo
);
8180 /* Update the global 'signal_catch' from INFO and notify the
8184 signal_catch_update (const unsigned int *info
)
8188 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
8189 signal_catch
[i
] = info
[i
] > 0;
8190 signal_cache_update (-1);
8191 target_pass_signals (signal_pass
);
8195 sig_print_header (void)
8197 printf_filtered (_("Signal Stop\tPrint\tPass "
8198 "to program\tDescription\n"));
8202 sig_print_info (enum gdb_signal oursig
)
8204 const char *name
= gdb_signal_to_name (oursig
);
8205 int name_padding
= 13 - strlen (name
);
8207 if (name_padding
<= 0)
8210 printf_filtered ("%s", name
);
8211 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
8212 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
8213 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
8214 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
8215 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
8218 /* Specify how various signals in the inferior should be handled. */
8221 handle_command (const char *args
, int from_tty
)
8223 int digits
, wordlen
;
8224 int sigfirst
, siglast
;
8225 enum gdb_signal oursig
;
8230 error_no_arg (_("signal to handle"));
8233 /* Allocate and zero an array of flags for which signals to handle. */
8235 const size_t nsigs
= GDB_SIGNAL_LAST
;
8236 unsigned char sigs
[nsigs
] {};
8238 /* Break the command line up into args. */
8240 gdb_argv
built_argv (args
);
8242 /* Walk through the args, looking for signal oursigs, signal names, and
8243 actions. Signal numbers and signal names may be interspersed with
8244 actions, with the actions being performed for all signals cumulatively
8245 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8247 for (char *arg
: built_argv
)
8249 wordlen
= strlen (arg
);
8250 for (digits
= 0; isdigit (arg
[digits
]); digits
++)
8254 sigfirst
= siglast
= -1;
8256 if (wordlen
>= 1 && !strncmp (arg
, "all", wordlen
))
8258 /* Apply action to all signals except those used by the
8259 debugger. Silently skip those. */
8262 siglast
= nsigs
- 1;
8264 else if (wordlen
>= 1 && !strncmp (arg
, "stop", wordlen
))
8266 SET_SIGS (nsigs
, sigs
, signal_stop
);
8267 SET_SIGS (nsigs
, sigs
, signal_print
);
8269 else if (wordlen
>= 1 && !strncmp (arg
, "ignore", wordlen
))
8271 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8273 else if (wordlen
>= 2 && !strncmp (arg
, "print", wordlen
))
8275 SET_SIGS (nsigs
, sigs
, signal_print
);
8277 else if (wordlen
>= 2 && !strncmp (arg
, "pass", wordlen
))
8279 SET_SIGS (nsigs
, sigs
, signal_program
);
8281 else if (wordlen
>= 3 && !strncmp (arg
, "nostop", wordlen
))
8283 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8285 else if (wordlen
>= 3 && !strncmp (arg
, "noignore", wordlen
))
8287 SET_SIGS (nsigs
, sigs
, signal_program
);
8289 else if (wordlen
>= 4 && !strncmp (arg
, "noprint", wordlen
))
8291 UNSET_SIGS (nsigs
, sigs
, signal_print
);
8292 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8294 else if (wordlen
>= 4 && !strncmp (arg
, "nopass", wordlen
))
8296 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8298 else if (digits
> 0)
8300 /* It is numeric. The numeric signal refers to our own
8301 internal signal numbering from target.h, not to host/target
8302 signal number. This is a feature; users really should be
8303 using symbolic names anyway, and the common ones like
8304 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8306 sigfirst
= siglast
= (int)
8307 gdb_signal_from_command (atoi (arg
));
8308 if (arg
[digits
] == '-')
8311 gdb_signal_from_command (atoi (arg
+ digits
+ 1));
8313 if (sigfirst
> siglast
)
8315 /* Bet he didn't figure we'd think of this case... */
8316 std::swap (sigfirst
, siglast
);
8321 oursig
= gdb_signal_from_name (arg
);
8322 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
8324 sigfirst
= siglast
= (int) oursig
;
8328 /* Not a number and not a recognized flag word => complain. */
8329 error (_("Unrecognized or ambiguous flag word: \"%s\"."), arg
);
8333 /* If any signal numbers or symbol names were found, set flags for
8334 which signals to apply actions to. */
8336 for (int signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
8338 switch ((enum gdb_signal
) signum
)
8340 case GDB_SIGNAL_TRAP
:
8341 case GDB_SIGNAL_INT
:
8342 if (!allsigs
&& !sigs
[signum
])
8344 if (query (_("%s is used by the debugger.\n\
8345 Are you sure you want to change it? "),
8346 gdb_signal_to_name ((enum gdb_signal
) signum
)))
8351 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8355 case GDB_SIGNAL_DEFAULT
:
8356 case GDB_SIGNAL_UNKNOWN
:
8357 /* Make sure that "all" doesn't print these. */
8366 for (int signum
= 0; signum
< nsigs
; signum
++)
8369 signal_cache_update (-1);
8370 target_pass_signals (signal_pass
);
8371 target_program_signals (signal_program
);
8375 /* Show the results. */
8376 sig_print_header ();
8377 for (; signum
< nsigs
; signum
++)
8379 sig_print_info ((enum gdb_signal
) signum
);
8386 /* Complete the "handle" command. */
8389 handle_completer (struct cmd_list_element
*ignore
,
8390 completion_tracker
&tracker
,
8391 const char *text
, const char *word
)
8393 static const char * const keywords
[] =
8407 signal_completer (ignore
, tracker
, text
, word
);
8408 complete_on_enum (tracker
, keywords
, word
, word
);
8412 gdb_signal_from_command (int num
)
8414 if (num
>= 1 && num
<= 15)
8415 return (enum gdb_signal
) num
;
8416 error (_("Only signals 1-15 are valid as numeric signals.\n\
8417 Use \"info signals\" for a list of symbolic signals."));
8420 /* Print current contents of the tables set by the handle command.
8421 It is possible we should just be printing signals actually used
8422 by the current target (but for things to work right when switching
8423 targets, all signals should be in the signal tables). */
8426 info_signals_command (const char *signum_exp
, int from_tty
)
8428 enum gdb_signal oursig
;
8430 sig_print_header ();
8434 /* First see if this is a symbol name. */
8435 oursig
= gdb_signal_from_name (signum_exp
);
8436 if (oursig
== GDB_SIGNAL_UNKNOWN
)
8438 /* No, try numeric. */
8440 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
8442 sig_print_info (oursig
);
8446 printf_filtered ("\n");
8447 /* These ugly casts brought to you by the native VAX compiler. */
8448 for (oursig
= GDB_SIGNAL_FIRST
;
8449 (int) oursig
< (int) GDB_SIGNAL_LAST
;
8450 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
8454 if (oursig
!= GDB_SIGNAL_UNKNOWN
8455 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
8456 sig_print_info (oursig
);
8459 printf_filtered (_("\nUse the \"handle\" command "
8460 "to change these tables.\n"));
8463 /* The $_siginfo convenience variable is a bit special. We don't know
8464 for sure the type of the value until we actually have a chance to
8465 fetch the data. The type can change depending on gdbarch, so it is
8466 also dependent on which thread you have selected.
8468 1. making $_siginfo be an internalvar that creates a new value on
8471 2. making the value of $_siginfo be an lval_computed value. */
8473 /* This function implements the lval_computed support for reading a
8477 siginfo_value_read (struct value
*v
)
8479 LONGEST transferred
;
8481 /* If we can access registers, so can we access $_siginfo. Likewise
8483 validate_registers_access ();
8486 target_read (current_top_target (), TARGET_OBJECT_SIGNAL_INFO
,
8488 value_contents_all_raw (v
),
8490 TYPE_LENGTH (value_type (v
)));
8492 if (transferred
!= TYPE_LENGTH (value_type (v
)))
8493 error (_("Unable to read siginfo"));
8496 /* This function implements the lval_computed support for writing a
8500 siginfo_value_write (struct value
*v
, struct value
*fromval
)
8502 LONGEST transferred
;
8504 /* If we can access registers, so can we access $_siginfo. Likewise
8506 validate_registers_access ();
8508 transferred
= target_write (current_top_target (),
8509 TARGET_OBJECT_SIGNAL_INFO
,
8511 value_contents_all_raw (fromval
),
8513 TYPE_LENGTH (value_type (fromval
)));
8515 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
8516 error (_("Unable to write siginfo"));
8519 static const struct lval_funcs siginfo_value_funcs
=
8525 /* Return a new value with the correct type for the siginfo object of
8526 the current thread using architecture GDBARCH. Return a void value
8527 if there's no object available. */
8529 static struct value
*
8530 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
8533 if (target_has_stack
8534 && inferior_ptid
!= null_ptid
8535 && gdbarch_get_siginfo_type_p (gdbarch
))
8537 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8539 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
8542 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
8546 /* infcall_suspend_state contains state about the program itself like its
8547 registers and any signal it received when it last stopped.
8548 This state must be restored regardless of how the inferior function call
8549 ends (either successfully, or after it hits a breakpoint or signal)
8550 if the program is to properly continue where it left off. */
8552 class infcall_suspend_state
8555 /* Capture state from GDBARCH, TP, and REGCACHE that must be restored
8556 once the inferior function call has finished. */
8557 infcall_suspend_state (struct gdbarch
*gdbarch
,
8558 const struct thread_info
*tp
,
8559 struct regcache
*regcache
)
8560 : m_thread_suspend (tp
->suspend
),
8561 m_registers (new readonly_detached_regcache (*regcache
))
8563 gdb::unique_xmalloc_ptr
<gdb_byte
> siginfo_data
;
8565 if (gdbarch_get_siginfo_type_p (gdbarch
))
8567 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8568 size_t len
= TYPE_LENGTH (type
);
8570 siginfo_data
.reset ((gdb_byte
*) xmalloc (len
));
8572 if (target_read (current_top_target (), TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8573 siginfo_data
.get (), 0, len
) != len
)
8575 /* Errors ignored. */
8576 siginfo_data
.reset (nullptr);
8582 m_siginfo_gdbarch
= gdbarch
;
8583 m_siginfo_data
= std::move (siginfo_data
);
8587 /* Return a pointer to the stored register state. */
8589 readonly_detached_regcache
*registers () const
8591 return m_registers
.get ();
8594 /* Restores the stored state into GDBARCH, TP, and REGCACHE. */
8596 void restore (struct gdbarch
*gdbarch
,
8597 struct thread_info
*tp
,
8598 struct regcache
*regcache
) const
8600 tp
->suspend
= m_thread_suspend
;
8602 if (m_siginfo_gdbarch
== gdbarch
)
8604 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8606 /* Errors ignored. */
8607 target_write (current_top_target (), TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8608 m_siginfo_data
.get (), 0, TYPE_LENGTH (type
));
8611 /* The inferior can be gone if the user types "print exit(0)"
8612 (and perhaps other times). */
8613 if (target_has_execution
)
8614 /* NB: The register write goes through to the target. */
8615 regcache
->restore (registers ());
8619 /* How the current thread stopped before the inferior function call was
8621 struct thread_suspend_state m_thread_suspend
;
8623 /* The registers before the inferior function call was executed. */
8624 std::unique_ptr
<readonly_detached_regcache
> m_registers
;
8626 /* Format of SIGINFO_DATA or NULL if it is not present. */
8627 struct gdbarch
*m_siginfo_gdbarch
= nullptr;
8629 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
8630 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
8631 content would be invalid. */
8632 gdb::unique_xmalloc_ptr
<gdb_byte
> m_siginfo_data
;
8635 infcall_suspend_state_up
8636 save_infcall_suspend_state ()
8638 struct thread_info
*tp
= inferior_thread ();
8639 struct regcache
*regcache
= get_current_regcache ();
8640 struct gdbarch
*gdbarch
= regcache
->arch ();
8642 infcall_suspend_state_up inf_state
8643 (new struct infcall_suspend_state (gdbarch
, tp
, regcache
));
8645 /* Having saved the current state, adjust the thread state, discarding
8646 any stop signal information. The stop signal is not useful when
8647 starting an inferior function call, and run_inferior_call will not use
8648 the signal due to its `proceed' call with GDB_SIGNAL_0. */
8649 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
8654 /* Restore inferior session state to INF_STATE. */
8657 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8659 struct thread_info
*tp
= inferior_thread ();
8660 struct regcache
*regcache
= get_current_regcache ();
8661 struct gdbarch
*gdbarch
= regcache
->arch ();
8663 inf_state
->restore (gdbarch
, tp
, regcache
);
8664 discard_infcall_suspend_state (inf_state
);
8668 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8673 readonly_detached_regcache
*
8674 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
8676 return inf_state
->registers ();
8679 /* infcall_control_state contains state regarding gdb's control of the
8680 inferior itself like stepping control. It also contains session state like
8681 the user's currently selected frame. */
8683 struct infcall_control_state
8685 struct thread_control_state thread_control
;
8686 struct inferior_control_state inferior_control
;
8689 enum stop_stack_kind stop_stack_dummy
= STOP_NONE
;
8690 int stopped_by_random_signal
= 0;
8692 /* ID if the selected frame when the inferior function call was made. */
8693 struct frame_id selected_frame_id
{};
8696 /* Save all of the information associated with the inferior<==>gdb
8699 infcall_control_state_up
8700 save_infcall_control_state ()
8702 infcall_control_state_up
inf_status (new struct infcall_control_state
);
8703 struct thread_info
*tp
= inferior_thread ();
8704 struct inferior
*inf
= current_inferior ();
8706 inf_status
->thread_control
= tp
->control
;
8707 inf_status
->inferior_control
= inf
->control
;
8709 tp
->control
.step_resume_breakpoint
= NULL
;
8710 tp
->control
.exception_resume_breakpoint
= NULL
;
8712 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
8713 chain. If caller's caller is walking the chain, they'll be happier if we
8714 hand them back the original chain when restore_infcall_control_state is
8716 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
8719 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
8720 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
8722 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
8728 restore_selected_frame (const frame_id
&fid
)
8730 frame_info
*frame
= frame_find_by_id (fid
);
8732 /* If inf_status->selected_frame_id is NULL, there was no previously
8736 warning (_("Unable to restore previously selected frame."));
8740 select_frame (frame
);
8743 /* Restore inferior session state to INF_STATUS. */
8746 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
8748 struct thread_info
*tp
= inferior_thread ();
8749 struct inferior
*inf
= current_inferior ();
8751 if (tp
->control
.step_resume_breakpoint
)
8752 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
8754 if (tp
->control
.exception_resume_breakpoint
)
8755 tp
->control
.exception_resume_breakpoint
->disposition
8756 = disp_del_at_next_stop
;
8758 /* Handle the bpstat_copy of the chain. */
8759 bpstat_clear (&tp
->control
.stop_bpstat
);
8761 tp
->control
= inf_status
->thread_control
;
8762 inf
->control
= inf_status
->inferior_control
;
8765 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
8766 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
8768 if (target_has_stack
)
8770 /* The point of the try/catch is that if the stack is clobbered,
8771 walking the stack might encounter a garbage pointer and
8772 error() trying to dereference it. */
8775 restore_selected_frame (inf_status
->selected_frame_id
);
8777 catch (const gdb_exception_error
&ex
)
8779 exception_fprintf (gdb_stderr
, ex
,
8780 "Unable to restore previously selected frame:\n");
8781 /* Error in restoring the selected frame. Select the
8783 select_frame (get_current_frame ());
8791 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
8793 if (inf_status
->thread_control
.step_resume_breakpoint
)
8794 inf_status
->thread_control
.step_resume_breakpoint
->disposition
8795 = disp_del_at_next_stop
;
8797 if (inf_status
->thread_control
.exception_resume_breakpoint
)
8798 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
8799 = disp_del_at_next_stop
;
8801 /* See save_infcall_control_state for info on stop_bpstat. */
8802 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
8810 clear_exit_convenience_vars (void)
8812 clear_internalvar (lookup_internalvar ("_exitsignal"));
8813 clear_internalvar (lookup_internalvar ("_exitcode"));
8817 /* User interface for reverse debugging:
8818 Set exec-direction / show exec-direction commands
8819 (returns error unless target implements to_set_exec_direction method). */
8821 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
8822 static const char exec_forward
[] = "forward";
8823 static const char exec_reverse
[] = "reverse";
8824 static const char *exec_direction
= exec_forward
;
8825 static const char *const exec_direction_names
[] = {
8832 set_exec_direction_func (const char *args
, int from_tty
,
8833 struct cmd_list_element
*cmd
)
8835 if (target_can_execute_reverse
)
8837 if (!strcmp (exec_direction
, exec_forward
))
8838 execution_direction
= EXEC_FORWARD
;
8839 else if (!strcmp (exec_direction
, exec_reverse
))
8840 execution_direction
= EXEC_REVERSE
;
8844 exec_direction
= exec_forward
;
8845 error (_("Target does not support this operation."));
8850 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
8851 struct cmd_list_element
*cmd
, const char *value
)
8853 switch (execution_direction
) {
8855 fprintf_filtered (out
, _("Forward.\n"));
8858 fprintf_filtered (out
, _("Reverse.\n"));
8861 internal_error (__FILE__
, __LINE__
,
8862 _("bogus execution_direction value: %d"),
8863 (int) execution_direction
);
8868 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
8869 struct cmd_list_element
*c
, const char *value
)
8871 fprintf_filtered (file
, _("Resuming the execution of threads "
8872 "of all processes is %s.\n"), value
);
8875 /* Implementation of `siginfo' variable. */
8877 static const struct internalvar_funcs siginfo_funcs
=
8884 /* Callback for infrun's target events source. This is marked when a
8885 thread has a pending status to process. */
8888 infrun_async_inferior_event_handler (gdb_client_data data
)
8890 inferior_event_handler (INF_REG_EVENT
, NULL
);
8894 _initialize_infrun (void)
8896 struct cmd_list_element
*c
;
8898 /* Register extra event sources in the event loop. */
8899 infrun_async_inferior_event_token
8900 = create_async_event_handler (infrun_async_inferior_event_handler
, NULL
);
8902 add_info ("signals", info_signals_command
, _("\
8903 What debugger does when program gets various signals.\n\
8904 Specify a signal as argument to print info on that signal only."));
8905 add_info_alias ("handle", "signals", 0);
8907 c
= add_com ("handle", class_run
, handle_command
, _("\
8908 Specify how to handle signals.\n\
8909 Usage: handle SIGNAL [ACTIONS]\n\
8910 Args are signals and actions to apply to those signals.\n\
8911 If no actions are specified, the current settings for the specified signals\n\
8912 will be displayed instead.\n\
8914 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
8915 from 1-15 are allowed for compatibility with old versions of GDB.\n\
8916 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
8917 The special arg \"all\" is recognized to mean all signals except those\n\
8918 used by the debugger, typically SIGTRAP and SIGINT.\n\
8920 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
8921 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
8922 Stop means reenter debugger if this signal happens (implies print).\n\
8923 Print means print a message if this signal happens.\n\
8924 Pass means let program see this signal; otherwise program doesn't know.\n\
8925 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
8926 Pass and Stop may be combined.\n\
8928 Multiple signals may be specified. Signal numbers and signal names\n\
8929 may be interspersed with actions, with the actions being performed for\n\
8930 all signals cumulatively specified."));
8931 set_cmd_completer (c
, handle_completer
);
8934 stop_command
= add_cmd ("stop", class_obscure
,
8935 not_just_help_class_command
, _("\
8936 There is no `stop' command, but you can set a hook on `stop'.\n\
8937 This allows you to set a list of commands to be run each time execution\n\
8938 of the program stops."), &cmdlist
);
8940 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
8941 Set inferior debugging."), _("\
8942 Show inferior debugging."), _("\
8943 When non-zero, inferior specific debugging is enabled."),
8946 &setdebuglist
, &showdebuglist
);
8948 add_setshow_boolean_cmd ("displaced", class_maintenance
,
8949 &debug_displaced
, _("\
8950 Set displaced stepping debugging."), _("\
8951 Show displaced stepping debugging."), _("\
8952 When non-zero, displaced stepping specific debugging is enabled."),
8954 show_debug_displaced
,
8955 &setdebuglist
, &showdebuglist
);
8957 add_setshow_boolean_cmd ("non-stop", no_class
,
8959 Set whether gdb controls the inferior in non-stop mode."), _("\
8960 Show whether gdb controls the inferior in non-stop mode."), _("\
8961 When debugging a multi-threaded program and this setting is\n\
8962 off (the default, also called all-stop mode), when one thread stops\n\
8963 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
8964 all other threads in the program while you interact with the thread of\n\
8965 interest. When you continue or step a thread, you can allow the other\n\
8966 threads to run, or have them remain stopped, but while you inspect any\n\
8967 thread's state, all threads stop.\n\
8969 In non-stop mode, when one thread stops, other threads can continue\n\
8970 to run freely. You'll be able to step each thread independently,\n\
8971 leave it stopped or free to run as needed."),
8977 for (size_t i
= 0; i
< GDB_SIGNAL_LAST
; i
++)
8980 signal_print
[i
] = 1;
8981 signal_program
[i
] = 1;
8982 signal_catch
[i
] = 0;
8985 /* Signals caused by debugger's own actions should not be given to
8986 the program afterwards.
8988 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
8989 explicitly specifies that it should be delivered to the target
8990 program. Typically, that would occur when a user is debugging a
8991 target monitor on a simulator: the target monitor sets a
8992 breakpoint; the simulator encounters this breakpoint and halts
8993 the simulation handing control to GDB; GDB, noting that the stop
8994 address doesn't map to any known breakpoint, returns control back
8995 to the simulator; the simulator then delivers the hardware
8996 equivalent of a GDB_SIGNAL_TRAP to the program being
8998 signal_program
[GDB_SIGNAL_TRAP
] = 0;
8999 signal_program
[GDB_SIGNAL_INT
] = 0;
9001 /* Signals that are not errors should not normally enter the debugger. */
9002 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
9003 signal_print
[GDB_SIGNAL_ALRM
] = 0;
9004 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
9005 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
9006 signal_stop
[GDB_SIGNAL_PROF
] = 0;
9007 signal_print
[GDB_SIGNAL_PROF
] = 0;
9008 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
9009 signal_print
[GDB_SIGNAL_CHLD
] = 0;
9010 signal_stop
[GDB_SIGNAL_IO
] = 0;
9011 signal_print
[GDB_SIGNAL_IO
] = 0;
9012 signal_stop
[GDB_SIGNAL_POLL
] = 0;
9013 signal_print
[GDB_SIGNAL_POLL
] = 0;
9014 signal_stop
[GDB_SIGNAL_URG
] = 0;
9015 signal_print
[GDB_SIGNAL_URG
] = 0;
9016 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
9017 signal_print
[GDB_SIGNAL_WINCH
] = 0;
9018 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
9019 signal_print
[GDB_SIGNAL_PRIO
] = 0;
9021 /* These signals are used internally by user-level thread
9022 implementations. (See signal(5) on Solaris.) Like the above
9023 signals, a healthy program receives and handles them as part of
9024 its normal operation. */
9025 signal_stop
[GDB_SIGNAL_LWP
] = 0;
9026 signal_print
[GDB_SIGNAL_LWP
] = 0;
9027 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
9028 signal_print
[GDB_SIGNAL_WAITING
] = 0;
9029 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
9030 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
9031 signal_stop
[GDB_SIGNAL_LIBRT
] = 0;
9032 signal_print
[GDB_SIGNAL_LIBRT
] = 0;
9034 /* Update cached state. */
9035 signal_cache_update (-1);
9037 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
9038 &stop_on_solib_events
, _("\
9039 Set stopping for shared library events."), _("\
9040 Show stopping for shared library events."), _("\
9041 If nonzero, gdb will give control to the user when the dynamic linker\n\
9042 notifies gdb of shared library events. The most common event of interest\n\
9043 to the user would be loading/unloading of a new library."),
9044 set_stop_on_solib_events
,
9045 show_stop_on_solib_events
,
9046 &setlist
, &showlist
);
9048 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
9049 follow_fork_mode_kind_names
,
9050 &follow_fork_mode_string
, _("\
9051 Set debugger response to a program call of fork or vfork."), _("\
9052 Show debugger response to a program call of fork or vfork."), _("\
9053 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9054 parent - the original process is debugged after a fork\n\
9055 child - the new process is debugged after a fork\n\
9056 The unfollowed process will continue to run.\n\
9057 By default, the debugger will follow the parent process."),
9059 show_follow_fork_mode_string
,
9060 &setlist
, &showlist
);
9062 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
9063 follow_exec_mode_names
,
9064 &follow_exec_mode_string
, _("\
9065 Set debugger response to a program call of exec."), _("\
9066 Show debugger response to a program call of exec."), _("\
9067 An exec call replaces the program image of a process.\n\
9069 follow-exec-mode can be:\n\
9071 new - the debugger creates a new inferior and rebinds the process\n\
9072 to this new inferior. The program the process was running before\n\
9073 the exec call can be restarted afterwards by restarting the original\n\
9076 same - the debugger keeps the process bound to the same inferior.\n\
9077 The new executable image replaces the previous executable loaded in\n\
9078 the inferior. Restarting the inferior after the exec call restarts\n\
9079 the executable the process was running after the exec call.\n\
9081 By default, the debugger will use the same inferior."),
9083 show_follow_exec_mode_string
,
9084 &setlist
, &showlist
);
9086 add_setshow_enum_cmd ("scheduler-locking", class_run
,
9087 scheduler_enums
, &scheduler_mode
, _("\
9088 Set mode for locking scheduler during execution."), _("\
9089 Show mode for locking scheduler during execution."), _("\
9090 off == no locking (threads may preempt at any time)\n\
9091 on == full locking (no thread except the current thread may run)\n\
9092 This applies to both normal execution and replay mode.\n\
9093 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9094 In this mode, other threads may run during other commands.\n\
9095 This applies to both normal execution and replay mode.\n\
9096 replay == scheduler locked in replay mode and unlocked during normal execution."),
9097 set_schedlock_func
, /* traps on target vector */
9098 show_scheduler_mode
,
9099 &setlist
, &showlist
);
9101 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
9102 Set mode for resuming threads of all processes."), _("\
9103 Show mode for resuming threads of all processes."), _("\
9104 When on, execution commands (such as 'continue' or 'next') resume all\n\
9105 threads of all processes. When off (which is the default), execution\n\
9106 commands only resume the threads of the current process. The set of\n\
9107 threads that are resumed is further refined by the scheduler-locking\n\
9108 mode (see help set scheduler-locking)."),
9110 show_schedule_multiple
,
9111 &setlist
, &showlist
);
9113 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
9114 Set mode of the step operation."), _("\
9115 Show mode of the step operation."), _("\
9116 When set, doing a step over a function without debug line information\n\
9117 will stop at the first instruction of that function. Otherwise, the\n\
9118 function is skipped and the step command stops at a different source line."),
9120 show_step_stop_if_no_debug
,
9121 &setlist
, &showlist
);
9123 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
9124 &can_use_displaced_stepping
, _("\
9125 Set debugger's willingness to use displaced stepping."), _("\
9126 Show debugger's willingness to use displaced stepping."), _("\
9127 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9128 supported by the target architecture. If off, gdb will not use displaced\n\
9129 stepping to step over breakpoints, even if such is supported by the target\n\
9130 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9131 if the target architecture supports it and non-stop mode is active, but will not\n\
9132 use it in all-stop mode (see help set non-stop)."),
9134 show_can_use_displaced_stepping
,
9135 &setlist
, &showlist
);
9137 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
9138 &exec_direction
, _("Set direction of execution.\n\
9139 Options are 'forward' or 'reverse'."),
9140 _("Show direction of execution (forward/reverse)."),
9141 _("Tells gdb whether to execute forward or backward."),
9142 set_exec_direction_func
, show_exec_direction_func
,
9143 &setlist
, &showlist
);
9145 /* Set/show detach-on-fork: user-settable mode. */
9147 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
9148 Set whether gdb will detach the child of a fork."), _("\
9149 Show whether gdb will detach the child of a fork."), _("\
9150 Tells gdb whether to detach the child of a fork."),
9151 NULL
, NULL
, &setlist
, &showlist
);
9153 /* Set/show disable address space randomization mode. */
9155 add_setshow_boolean_cmd ("disable-randomization", class_support
,
9156 &disable_randomization
, _("\
9157 Set disabling of debuggee's virtual address space randomization."), _("\
9158 Show disabling of debuggee's virtual address space randomization."), _("\
9159 When this mode is on (which is the default), randomization of the virtual\n\
9160 address space is disabled. Standalone programs run with the randomization\n\
9161 enabled by default on some platforms."),
9162 &set_disable_randomization
,
9163 &show_disable_randomization
,
9164 &setlist
, &showlist
);
9166 /* ptid initializations */
9167 inferior_ptid
= null_ptid
;
9168 target_last_wait_ptid
= minus_one_ptid
;
9170 gdb::observers::thread_ptid_changed
.attach (infrun_thread_ptid_changed
);
9171 gdb::observers::thread_stop_requested
.attach (infrun_thread_stop_requested
);
9172 gdb::observers::thread_exit
.attach (infrun_thread_thread_exit
);
9173 gdb::observers::inferior_exit
.attach (infrun_inferior_exit
);
9175 /* Explicitly create without lookup, since that tries to create a
9176 value with a void typed value, and when we get here, gdbarch
9177 isn't initialized yet. At this point, we're quite sure there
9178 isn't another convenience variable of the same name. */
9179 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
9181 add_setshow_boolean_cmd ("observer", no_class
,
9182 &observer_mode_1
, _("\
9183 Set whether gdb controls the inferior in observer mode."), _("\
9184 Show whether gdb controls the inferior in observer mode."), _("\
9185 In observer mode, GDB can get data from the inferior, but not\n\
9186 affect its execution. Registers and memory may not be changed,\n\
9187 breakpoints may not be set, and the program cannot be interrupted\n\