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 /* Look for an inline frame that is marked for skip.
4039 If PREV_FRAME is TRUE start at the previous frame,
4040 otherwise start at the current frame. Stop at the
4041 first non-inline frame, or at the frame where the
4045 inline_frame_is_marked_for_skip (bool prev_frame
, struct thread_info
*tp
)
4047 struct frame_info
*frame
= get_current_frame ();
4050 frame
= get_prev_frame (frame
);
4052 for (; frame
!= NULL
; frame
= get_prev_frame (frame
))
4054 const char *fn
= NULL
;
4055 symtab_and_line sal
;
4058 if (frame_id_eq (get_frame_id (frame
), tp
->control
.step_frame_id
))
4060 if (get_frame_type (frame
) != INLINE_FRAME
)
4063 sal
= find_frame_sal (frame
);
4064 sym
= get_frame_function (frame
);
4067 fn
= sym
->print_name ();
4070 && function_name_is_marked_for_skip (fn
, sal
))
4077 /* If the event thread has the stop requested flag set, pretend it
4078 stopped for a GDB_SIGNAL_0 (i.e., as if it stopped due to
4082 handle_stop_requested (struct execution_control_state
*ecs
)
4084 if (ecs
->event_thread
->stop_requested
)
4086 ecs
->ws
.kind
= TARGET_WAITKIND_STOPPED
;
4087 ecs
->ws
.value
.sig
= GDB_SIGNAL_0
;
4088 handle_signal_stop (ecs
);
4094 /* Auxiliary function that handles syscall entry/return events.
4095 It returns 1 if the inferior should keep going (and GDB
4096 should ignore the event), or 0 if the event deserves to be
4100 handle_syscall_event (struct execution_control_state
*ecs
)
4102 struct regcache
*regcache
;
4105 context_switch (ecs
);
4107 regcache
= get_thread_regcache (ecs
->event_thread
);
4108 syscall_number
= ecs
->ws
.value
.syscall_number
;
4109 ecs
->event_thread
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4111 if (catch_syscall_enabled () > 0
4112 && catching_syscall_number (syscall_number
) > 0)
4115 fprintf_unfiltered (gdb_stdlog
, "infrun: syscall number = '%d'\n",
4118 ecs
->event_thread
->control
.stop_bpstat
4119 = bpstat_stop_status (regcache
->aspace (),
4120 ecs
->event_thread
->suspend
.stop_pc
,
4121 ecs
->event_thread
, &ecs
->ws
);
4123 if (handle_stop_requested (ecs
))
4126 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4128 /* Catchpoint hit. */
4133 if (handle_stop_requested (ecs
))
4136 /* If no catchpoint triggered for this, then keep going. */
4141 /* Lazily fill in the execution_control_state's stop_func_* fields. */
4144 fill_in_stop_func (struct gdbarch
*gdbarch
,
4145 struct execution_control_state
*ecs
)
4147 if (!ecs
->stop_func_filled_in
)
4151 /* Don't care about return value; stop_func_start and stop_func_name
4152 will both be 0 if it doesn't work. */
4153 find_pc_partial_function (ecs
->event_thread
->suspend
.stop_pc
,
4154 &ecs
->stop_func_name
,
4155 &ecs
->stop_func_start
,
4156 &ecs
->stop_func_end
,
4159 /* The call to find_pc_partial_function, above, will set
4160 stop_func_start and stop_func_end to the start and end
4161 of the range containing the stop pc. If this range
4162 contains the entry pc for the block (which is always the
4163 case for contiguous blocks), advance stop_func_start past
4164 the function's start offset and entrypoint. Note that
4165 stop_func_start is NOT advanced when in a range of a
4166 non-contiguous block that does not contain the entry pc. */
4167 if (block
!= nullptr
4168 && ecs
->stop_func_start
<= BLOCK_ENTRY_PC (block
)
4169 && BLOCK_ENTRY_PC (block
) < ecs
->stop_func_end
)
4171 ecs
->stop_func_start
4172 += gdbarch_deprecated_function_start_offset (gdbarch
);
4174 if (gdbarch_skip_entrypoint_p (gdbarch
))
4175 ecs
->stop_func_start
4176 = gdbarch_skip_entrypoint (gdbarch
, ecs
->stop_func_start
);
4179 ecs
->stop_func_filled_in
= 1;
4184 /* Return the STOP_SOON field of the inferior pointed at by ECS. */
4186 static enum stop_kind
4187 get_inferior_stop_soon (execution_control_state
*ecs
)
4189 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
4191 gdb_assert (inf
!= NULL
);
4192 return inf
->control
.stop_soon
;
4195 /* Wait for one event. Store the resulting waitstatus in WS, and
4196 return the event ptid. */
4199 wait_one (struct target_waitstatus
*ws
)
4202 ptid_t wait_ptid
= minus_one_ptid
;
4204 overlay_cache_invalid
= 1;
4206 /* Flush target cache before starting to handle each event.
4207 Target was running and cache could be stale. This is just a
4208 heuristic. Running threads may modify target memory, but we
4209 don't get any event. */
4210 target_dcache_invalidate ();
4212 if (deprecated_target_wait_hook
)
4213 event_ptid
= deprecated_target_wait_hook (wait_ptid
, ws
, 0);
4215 event_ptid
= target_wait (wait_ptid
, ws
, 0);
4218 print_target_wait_results (wait_ptid
, event_ptid
, ws
);
4223 /* Generate a wrapper for target_stopped_by_REASON that works on PTID
4224 instead of the current thread. */
4225 #define THREAD_STOPPED_BY(REASON) \
4227 thread_stopped_by_ ## REASON (ptid_t ptid) \
4229 scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid); \
4230 inferior_ptid = ptid; \
4232 return target_stopped_by_ ## REASON (); \
4235 /* Generate thread_stopped_by_watchpoint. */
4236 THREAD_STOPPED_BY (watchpoint
)
4237 /* Generate thread_stopped_by_sw_breakpoint. */
4238 THREAD_STOPPED_BY (sw_breakpoint
)
4239 /* Generate thread_stopped_by_hw_breakpoint. */
4240 THREAD_STOPPED_BY (hw_breakpoint
)
4242 /* Save the thread's event and stop reason to process it later. */
4245 save_waitstatus (struct thread_info
*tp
, struct target_waitstatus
*ws
)
4249 std::string statstr
= target_waitstatus_to_string (ws
);
4251 fprintf_unfiltered (gdb_stdlog
,
4252 "infrun: saving status %s for %d.%ld.%ld\n",
4259 /* Record for later. */
4260 tp
->suspend
.waitstatus
= *ws
;
4261 tp
->suspend
.waitstatus_pending_p
= 1;
4263 struct regcache
*regcache
= get_thread_regcache (tp
);
4264 const address_space
*aspace
= regcache
->aspace ();
4266 if (ws
->kind
== TARGET_WAITKIND_STOPPED
4267 && ws
->value
.sig
== GDB_SIGNAL_TRAP
)
4269 CORE_ADDR pc
= regcache_read_pc (regcache
);
4271 adjust_pc_after_break (tp
, &tp
->suspend
.waitstatus
);
4273 if (thread_stopped_by_watchpoint (tp
->ptid
))
4275 tp
->suspend
.stop_reason
4276 = TARGET_STOPPED_BY_WATCHPOINT
;
4278 else if (target_supports_stopped_by_sw_breakpoint ()
4279 && thread_stopped_by_sw_breakpoint (tp
->ptid
))
4281 tp
->suspend
.stop_reason
4282 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4284 else if (target_supports_stopped_by_hw_breakpoint ()
4285 && thread_stopped_by_hw_breakpoint (tp
->ptid
))
4287 tp
->suspend
.stop_reason
4288 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4290 else if (!target_supports_stopped_by_hw_breakpoint ()
4291 && hardware_breakpoint_inserted_here_p (aspace
,
4294 tp
->suspend
.stop_reason
4295 = TARGET_STOPPED_BY_HW_BREAKPOINT
;
4297 else if (!target_supports_stopped_by_sw_breakpoint ()
4298 && software_breakpoint_inserted_here_p (aspace
,
4301 tp
->suspend
.stop_reason
4302 = TARGET_STOPPED_BY_SW_BREAKPOINT
;
4304 else if (!thread_has_single_step_breakpoints_set (tp
)
4305 && currently_stepping (tp
))
4307 tp
->suspend
.stop_reason
4308 = TARGET_STOPPED_BY_SINGLE_STEP
;
4316 stop_all_threads (void)
4318 /* We may need multiple passes to discover all threads. */
4322 gdb_assert (target_is_non_stop_p ());
4325 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads\n");
4327 scoped_restore_current_thread restore_thread
;
4329 target_thread_events (1);
4330 SCOPE_EXIT
{ target_thread_events (0); };
4332 /* Request threads to stop, and then wait for the stops. Because
4333 threads we already know about can spawn more threads while we're
4334 trying to stop them, and we only learn about new threads when we
4335 update the thread list, do this in a loop, and keep iterating
4336 until two passes find no threads that need to be stopped. */
4337 for (pass
= 0; pass
< 2; pass
++, iterations
++)
4340 fprintf_unfiltered (gdb_stdlog
,
4341 "infrun: stop_all_threads, pass=%d, "
4342 "iterations=%d\n", pass
, iterations
);
4346 struct target_waitstatus ws
;
4349 update_thread_list ();
4351 /* Go through all threads looking for threads that we need
4352 to tell the target to stop. */
4353 for (thread_info
*t
: all_non_exited_threads ())
4357 /* If already stopping, don't request a stop again.
4358 We just haven't seen the notification yet. */
4359 if (!t
->stop_requested
)
4362 fprintf_unfiltered (gdb_stdlog
,
4363 "infrun: %s executing, "
4365 target_pid_to_str (t
->ptid
).c_str ());
4366 target_stop (t
->ptid
);
4367 t
->stop_requested
= 1;
4372 fprintf_unfiltered (gdb_stdlog
,
4373 "infrun: %s executing, "
4374 "already stopping\n",
4375 target_pid_to_str (t
->ptid
).c_str ());
4378 if (t
->stop_requested
)
4384 fprintf_unfiltered (gdb_stdlog
,
4385 "infrun: %s not executing\n",
4386 target_pid_to_str (t
->ptid
).c_str ());
4388 /* The thread may be not executing, but still be
4389 resumed with a pending status to process. */
4397 /* If we find new threads on the second iteration, restart
4398 over. We want to see two iterations in a row with all
4403 event_ptid
= wait_one (&ws
);
4406 fprintf_unfiltered (gdb_stdlog
,
4407 "infrun: stop_all_threads %s %s\n",
4408 target_waitstatus_to_string (&ws
).c_str (),
4409 target_pid_to_str (event_ptid
).c_str ());
4412 if (ws
.kind
== TARGET_WAITKIND_NO_RESUMED
4413 || ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
4414 || ws
.kind
== TARGET_WAITKIND_EXITED
4415 || ws
.kind
== TARGET_WAITKIND_SIGNALLED
)
4417 /* All resumed threads exited
4418 or one thread/process exited/signalled. */
4422 thread_info
*t
= find_thread_ptid (event_ptid
);
4424 t
= add_thread (event_ptid
);
4426 t
->stop_requested
= 0;
4429 t
->control
.may_range_step
= 0;
4431 /* This may be the first time we see the inferior report
4433 inferior
*inf
= find_inferior_ptid (event_ptid
);
4434 if (inf
->needs_setup
)
4436 switch_to_thread_no_regs (t
);
4440 if (ws
.kind
== TARGET_WAITKIND_STOPPED
4441 && ws
.value
.sig
== GDB_SIGNAL_0
)
4443 /* We caught the event that we intended to catch, so
4444 there's no event pending. */
4445 t
->suspend
.waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
4446 t
->suspend
.waitstatus_pending_p
= 0;
4448 if (displaced_step_fixup (t
, GDB_SIGNAL_0
) < 0)
4450 /* Add it back to the step-over queue. */
4453 fprintf_unfiltered (gdb_stdlog
,
4454 "infrun: displaced-step of %s "
4455 "canceled: adding back to the "
4456 "step-over queue\n",
4457 target_pid_to_str (t
->ptid
).c_str ());
4459 t
->control
.trap_expected
= 0;
4460 thread_step_over_chain_enqueue (t
);
4465 enum gdb_signal sig
;
4466 struct regcache
*regcache
;
4470 std::string statstr
= target_waitstatus_to_string (&ws
);
4472 fprintf_unfiltered (gdb_stdlog
,
4473 "infrun: target_wait %s, saving "
4474 "status for %d.%ld.%ld\n",
4481 /* Record for later. */
4482 save_waitstatus (t
, &ws
);
4484 sig
= (ws
.kind
== TARGET_WAITKIND_STOPPED
4485 ? ws
.value
.sig
: GDB_SIGNAL_0
);
4487 if (displaced_step_fixup (t
, sig
) < 0)
4489 /* Add it back to the step-over queue. */
4490 t
->control
.trap_expected
= 0;
4491 thread_step_over_chain_enqueue (t
);
4494 regcache
= get_thread_regcache (t
);
4495 t
->suspend
.stop_pc
= regcache_read_pc (regcache
);
4499 fprintf_unfiltered (gdb_stdlog
,
4500 "infrun: saved stop_pc=%s for %s "
4501 "(currently_stepping=%d)\n",
4502 paddress (target_gdbarch (),
4503 t
->suspend
.stop_pc
),
4504 target_pid_to_str (t
->ptid
).c_str (),
4505 currently_stepping (t
));
4513 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_all_threads done\n");
4516 /* Handle a TARGET_WAITKIND_NO_RESUMED event. */
4519 handle_no_resumed (struct execution_control_state
*ecs
)
4521 if (target_can_async_p ())
4528 if (ui
->prompt_state
== PROMPT_BLOCKED
)
4536 /* There were no unwaited-for children left in the target, but,
4537 we're not synchronously waiting for events either. Just
4541 fprintf_unfiltered (gdb_stdlog
,
4542 "infrun: TARGET_WAITKIND_NO_RESUMED "
4543 "(ignoring: bg)\n");
4544 prepare_to_wait (ecs
);
4549 /* Otherwise, if we were running a synchronous execution command, we
4550 may need to cancel it and give the user back the terminal.
4552 In non-stop mode, the target can't tell whether we've already
4553 consumed previous stop events, so it can end up sending us a
4554 no-resumed event like so:
4556 #0 - thread 1 is left stopped
4558 #1 - thread 2 is resumed and hits breakpoint
4559 -> TARGET_WAITKIND_STOPPED
4561 #2 - thread 3 is resumed and exits
4562 this is the last resumed thread, so
4563 -> TARGET_WAITKIND_NO_RESUMED
4565 #3 - gdb processes stop for thread 2 and decides to re-resume
4568 #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
4569 thread 2 is now resumed, so the event should be ignored.
4571 IOW, if the stop for thread 2 doesn't end a foreground command,
4572 then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
4573 event. But it could be that the event meant that thread 2 itself
4574 (or whatever other thread was the last resumed thread) exited.
4576 To address this we refresh the thread list and check whether we
4577 have resumed threads _now_. In the example above, this removes
4578 thread 3 from the thread list. If thread 2 was re-resumed, we
4579 ignore this event. If we find no thread resumed, then we cancel
4580 the synchronous command show "no unwaited-for " to the user. */
4581 update_thread_list ();
4583 for (thread_info
*thread
: all_non_exited_threads ())
4585 if (thread
->executing
4586 || thread
->suspend
.waitstatus_pending_p
)
4588 /* There were no unwaited-for children left in the target at
4589 some point, but there are now. Just ignore. */
4591 fprintf_unfiltered (gdb_stdlog
,
4592 "infrun: TARGET_WAITKIND_NO_RESUMED "
4593 "(ignoring: found resumed)\n");
4594 prepare_to_wait (ecs
);
4599 /* Note however that we may find no resumed thread because the whole
4600 process exited meanwhile (thus updating the thread list results
4601 in an empty thread list). In this case we know we'll be getting
4602 a process exit event shortly. */
4603 for (inferior
*inf
: all_inferiors ())
4608 thread_info
*thread
= any_live_thread_of_inferior (inf
);
4612 fprintf_unfiltered (gdb_stdlog
,
4613 "infrun: TARGET_WAITKIND_NO_RESUMED "
4614 "(expect process exit)\n");
4615 prepare_to_wait (ecs
);
4620 /* Go ahead and report the event. */
4624 /* Given an execution control state that has been freshly filled in by
4625 an event from the inferior, figure out what it means and take
4628 The alternatives are:
4630 1) stop_waiting and return; to really stop and return to the
4633 2) keep_going and return; to wait for the next event (set
4634 ecs->event_thread->stepping_over_breakpoint to 1 to single step
4638 handle_inferior_event (struct execution_control_state
*ecs
)
4640 /* Make sure that all temporary struct value objects that were
4641 created during the handling of the event get deleted at the
4643 scoped_value_mark free_values
;
4645 enum stop_kind stop_soon
;
4648 fprintf_unfiltered (gdb_stdlog
, "infrun: handle_inferior_event %s\n",
4649 target_waitstatus_to_string (&ecs
->ws
).c_str ());
4651 if (ecs
->ws
.kind
== TARGET_WAITKIND_IGNORE
)
4653 /* We had an event in the inferior, but we are not interested in
4654 handling it at this level. The lower layers have already
4655 done what needs to be done, if anything.
4657 One of the possible circumstances for this is when the
4658 inferior produces output for the console. The inferior has
4659 not stopped, and we are ignoring the event. Another possible
4660 circumstance is any event which the lower level knows will be
4661 reported multiple times without an intervening resume. */
4662 prepare_to_wait (ecs
);
4666 if (ecs
->ws
.kind
== TARGET_WAITKIND_THREAD_EXITED
)
4668 prepare_to_wait (ecs
);
4672 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
4673 && handle_no_resumed (ecs
))
4676 /* Cache the last pid/waitstatus. */
4677 set_last_target_status (ecs
->ptid
, ecs
->ws
);
4679 /* Always clear state belonging to the previous time we stopped. */
4680 stop_stack_dummy
= STOP_NONE
;
4682 if (ecs
->ws
.kind
== TARGET_WAITKIND_NO_RESUMED
)
4684 /* No unwaited-for children left. IOW, all resumed children
4686 stop_print_frame
= 0;
4691 if (ecs
->ws
.kind
!= TARGET_WAITKIND_EXITED
4692 && ecs
->ws
.kind
!= TARGET_WAITKIND_SIGNALLED
)
4694 ecs
->event_thread
= find_thread_ptid (ecs
->ptid
);
4695 /* If it's a new thread, add it to the thread database. */
4696 if (ecs
->event_thread
== NULL
)
4697 ecs
->event_thread
= add_thread (ecs
->ptid
);
4699 /* Disable range stepping. If the next step request could use a
4700 range, this will be end up re-enabled then. */
4701 ecs
->event_thread
->control
.may_range_step
= 0;
4704 /* Dependent on valid ECS->EVENT_THREAD. */
4705 adjust_pc_after_break (ecs
->event_thread
, &ecs
->ws
);
4707 /* Dependent on the current PC value modified by adjust_pc_after_break. */
4708 reinit_frame_cache ();
4710 breakpoint_retire_moribund ();
4712 /* First, distinguish signals caused by the debugger from signals
4713 that have to do with the program's own actions. Note that
4714 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
4715 on the operating system version. Here we detect when a SIGILL or
4716 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
4717 something similar for SIGSEGV, since a SIGSEGV will be generated
4718 when we're trying to execute a breakpoint instruction on a
4719 non-executable stack. This happens for call dummy breakpoints
4720 for architectures like SPARC that place call dummies on the
4722 if (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
4723 && (ecs
->ws
.value
.sig
== GDB_SIGNAL_ILL
4724 || ecs
->ws
.value
.sig
== GDB_SIGNAL_SEGV
4725 || ecs
->ws
.value
.sig
== GDB_SIGNAL_EMT
))
4727 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
4729 if (breakpoint_inserted_here_p (regcache
->aspace (),
4730 regcache_read_pc (regcache
)))
4733 fprintf_unfiltered (gdb_stdlog
,
4734 "infrun: Treating signal as SIGTRAP\n");
4735 ecs
->ws
.value
.sig
= GDB_SIGNAL_TRAP
;
4739 /* Mark the non-executing threads accordingly. In all-stop, all
4740 threads of all processes are stopped when we get any event
4741 reported. In non-stop mode, only the event thread stops. */
4745 if (!target_is_non_stop_p ())
4746 mark_ptid
= minus_one_ptid
;
4747 else if (ecs
->ws
.kind
== TARGET_WAITKIND_SIGNALLED
4748 || ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4750 /* If we're handling a process exit in non-stop mode, even
4751 though threads haven't been deleted yet, one would think
4752 that there is nothing to do, as threads of the dead process
4753 will be soon deleted, and threads of any other process were
4754 left running. However, on some targets, threads survive a
4755 process exit event. E.g., for the "checkpoint" command,
4756 when the current checkpoint/fork exits, linux-fork.c
4757 automatically switches to another fork from within
4758 target_mourn_inferior, by associating the same
4759 inferior/thread to another fork. We haven't mourned yet at
4760 this point, but we must mark any threads left in the
4761 process as not-executing so that finish_thread_state marks
4762 them stopped (in the user's perspective) if/when we present
4763 the stop to the user. */
4764 mark_ptid
= ptid_t (ecs
->ptid
.pid ());
4767 mark_ptid
= ecs
->ptid
;
4769 set_executing (mark_ptid
, 0);
4771 /* Likewise the resumed flag. */
4772 set_resumed (mark_ptid
, 0);
4775 switch (ecs
->ws
.kind
)
4777 case TARGET_WAITKIND_LOADED
:
4778 context_switch (ecs
);
4779 /* Ignore gracefully during startup of the inferior, as it might
4780 be the shell which has just loaded some objects, otherwise
4781 add the symbols for the newly loaded objects. Also ignore at
4782 the beginning of an attach or remote session; we will query
4783 the full list of libraries once the connection is
4786 stop_soon
= get_inferior_stop_soon (ecs
);
4787 if (stop_soon
== NO_STOP_QUIETLY
)
4789 struct regcache
*regcache
;
4791 regcache
= get_thread_regcache (ecs
->event_thread
);
4793 handle_solib_event ();
4795 ecs
->event_thread
->control
.stop_bpstat
4796 = bpstat_stop_status (regcache
->aspace (),
4797 ecs
->event_thread
->suspend
.stop_pc
,
4798 ecs
->event_thread
, &ecs
->ws
);
4800 if (handle_stop_requested (ecs
))
4803 if (bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
4805 /* A catchpoint triggered. */
4806 process_event_stop_test (ecs
);
4810 /* If requested, stop when the dynamic linker notifies
4811 gdb of events. This allows the user to get control
4812 and place breakpoints in initializer routines for
4813 dynamically loaded objects (among other things). */
4814 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
4815 if (stop_on_solib_events
)
4817 /* Make sure we print "Stopped due to solib-event" in
4819 stop_print_frame
= 1;
4826 /* If we are skipping through a shell, or through shared library
4827 loading that we aren't interested in, resume the program. If
4828 we're running the program normally, also resume. */
4829 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== NO_STOP_QUIETLY
)
4831 /* Loading of shared libraries might have changed breakpoint
4832 addresses. Make sure new breakpoints are inserted. */
4833 if (stop_soon
== NO_STOP_QUIETLY
)
4834 insert_breakpoints ();
4835 resume (GDB_SIGNAL_0
);
4836 prepare_to_wait (ecs
);
4840 /* But stop if we're attaching or setting up a remote
4842 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
4843 || stop_soon
== STOP_QUIETLY_REMOTE
)
4846 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
4851 internal_error (__FILE__
, __LINE__
,
4852 _("unhandled stop_soon: %d"), (int) stop_soon
);
4854 case TARGET_WAITKIND_SPURIOUS
:
4855 if (handle_stop_requested (ecs
))
4857 context_switch (ecs
);
4858 resume (GDB_SIGNAL_0
);
4859 prepare_to_wait (ecs
);
4862 case TARGET_WAITKIND_THREAD_CREATED
:
4863 if (handle_stop_requested (ecs
))
4865 context_switch (ecs
);
4866 if (!switch_back_to_stepped_thread (ecs
))
4870 case TARGET_WAITKIND_EXITED
:
4871 case TARGET_WAITKIND_SIGNALLED
:
4872 inferior_ptid
= ecs
->ptid
;
4873 set_current_inferior (find_inferior_ptid (ecs
->ptid
));
4874 set_current_program_space (current_inferior ()->pspace
);
4875 handle_vfork_child_exec_or_exit (0);
4876 target_terminal::ours (); /* Must do this before mourn anyway. */
4878 /* Clearing any previous state of convenience variables. */
4879 clear_exit_convenience_vars ();
4881 if (ecs
->ws
.kind
== TARGET_WAITKIND_EXITED
)
4883 /* Record the exit code in the convenience variable $_exitcode, so
4884 that the user can inspect this again later. */
4885 set_internalvar_integer (lookup_internalvar ("_exitcode"),
4886 (LONGEST
) ecs
->ws
.value
.integer
);
4888 /* Also record this in the inferior itself. */
4889 current_inferior ()->has_exit_code
= 1;
4890 current_inferior ()->exit_code
= (LONGEST
) ecs
->ws
.value
.integer
;
4892 /* Support the --return-child-result option. */
4893 return_child_result_value
= ecs
->ws
.value
.integer
;
4895 gdb::observers::exited
.notify (ecs
->ws
.value
.integer
);
4899 struct gdbarch
*gdbarch
= current_inferior ()->gdbarch
;
4901 if (gdbarch_gdb_signal_to_target_p (gdbarch
))
4903 /* Set the value of the internal variable $_exitsignal,
4904 which holds the signal uncaught by the inferior. */
4905 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
4906 gdbarch_gdb_signal_to_target (gdbarch
,
4907 ecs
->ws
.value
.sig
));
4911 /* We don't have access to the target's method used for
4912 converting between signal numbers (GDB's internal
4913 representation <-> target's representation).
4914 Therefore, we cannot do a good job at displaying this
4915 information to the user. It's better to just warn
4916 her about it (if infrun debugging is enabled), and
4919 fprintf_filtered (gdb_stdlog
, _("\
4920 Cannot fill $_exitsignal with the correct signal number.\n"));
4923 gdb::observers::signal_exited
.notify (ecs
->ws
.value
.sig
);
4926 gdb_flush (gdb_stdout
);
4927 target_mourn_inferior (inferior_ptid
);
4928 stop_print_frame
= 0;
4932 /* The following are the only cases in which we keep going;
4933 the above cases end in a continue or goto. */
4934 case TARGET_WAITKIND_FORKED
:
4935 case TARGET_WAITKIND_VFORKED
:
4936 /* Check whether the inferior is displaced stepping. */
4938 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
4939 struct gdbarch
*gdbarch
= regcache
->arch ();
4941 /* If checking displaced stepping is supported, and thread
4942 ecs->ptid is displaced stepping. */
4943 if (displaced_step_in_progress_thread (ecs
->event_thread
))
4945 struct inferior
*parent_inf
4946 = find_inferior_ptid (ecs
->ptid
);
4947 struct regcache
*child_regcache
;
4948 CORE_ADDR parent_pc
;
4950 /* GDB has got TARGET_WAITKIND_FORKED or TARGET_WAITKIND_VFORKED,
4951 indicating that the displaced stepping of syscall instruction
4952 has been done. Perform cleanup for parent process here. Note
4953 that this operation also cleans up the child process for vfork,
4954 because their pages are shared. */
4955 displaced_step_fixup (ecs
->event_thread
, GDB_SIGNAL_TRAP
);
4956 /* Start a new step-over in another thread if there's one
4960 if (ecs
->ws
.kind
== TARGET_WAITKIND_FORKED
)
4962 struct displaced_step_inferior_state
*displaced
4963 = get_displaced_stepping_state (parent_inf
);
4965 /* Restore scratch pad for child process. */
4966 displaced_step_restore (displaced
, ecs
->ws
.value
.related_pid
);
4969 /* Since the vfork/fork syscall instruction was executed in the scratchpad,
4970 the child's PC is also within the scratchpad. Set the child's PC
4971 to the parent's PC value, which has already been fixed up.
4972 FIXME: we use the parent's aspace here, although we're touching
4973 the child, because the child hasn't been added to the inferior
4974 list yet at this point. */
4977 = get_thread_arch_aspace_regcache (ecs
->ws
.value
.related_pid
,
4979 parent_inf
->aspace
);
4980 /* Read PC value of parent process. */
4981 parent_pc
= regcache_read_pc (regcache
);
4983 if (debug_displaced
)
4984 fprintf_unfiltered (gdb_stdlog
,
4985 "displaced: write child pc from %s to %s\n",
4987 regcache_read_pc (child_regcache
)),
4988 paddress (gdbarch
, parent_pc
));
4990 regcache_write_pc (child_regcache
, parent_pc
);
4994 context_switch (ecs
);
4996 /* Immediately detach breakpoints from the child before there's
4997 any chance of letting the user delete breakpoints from the
4998 breakpoint lists. If we don't do this early, it's easy to
4999 leave left over traps in the child, vis: "break foo; catch
5000 fork; c; <fork>; del; c; <child calls foo>". We only follow
5001 the fork on the last `continue', and by that time the
5002 breakpoint at "foo" is long gone from the breakpoint table.
5003 If we vforked, then we don't need to unpatch here, since both
5004 parent and child are sharing the same memory pages; we'll
5005 need to unpatch at follow/detach time instead to be certain
5006 that new breakpoints added between catchpoint hit time and
5007 vfork follow are detached. */
5008 if (ecs
->ws
.kind
!= TARGET_WAITKIND_VFORKED
)
5010 /* This won't actually modify the breakpoint list, but will
5011 physically remove the breakpoints from the child. */
5012 detach_breakpoints (ecs
->ws
.value
.related_pid
);
5015 delete_just_stopped_threads_single_step_breakpoints ();
5017 /* In case the event is caught by a catchpoint, remember that
5018 the event is to be followed at the next resume of the thread,
5019 and not immediately. */
5020 ecs
->event_thread
->pending_follow
= ecs
->ws
;
5022 ecs
->event_thread
->suspend
.stop_pc
5023 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
5025 ecs
->event_thread
->control
.stop_bpstat
5026 = bpstat_stop_status (get_current_regcache ()->aspace (),
5027 ecs
->event_thread
->suspend
.stop_pc
,
5028 ecs
->event_thread
, &ecs
->ws
);
5030 if (handle_stop_requested (ecs
))
5033 /* If no catchpoint triggered for this, then keep going. Note
5034 that we're interested in knowing the bpstat actually causes a
5035 stop, not just if it may explain the signal. Software
5036 watchpoints, for example, always appear in the bpstat. */
5037 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5041 = (follow_fork_mode_string
== follow_fork_mode_child
);
5043 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5045 should_resume
= follow_fork ();
5047 thread_info
*parent
= ecs
->event_thread
;
5048 thread_info
*child
= find_thread_ptid (ecs
->ws
.value
.related_pid
);
5050 /* At this point, the parent is marked running, and the
5051 child is marked stopped. */
5053 /* If not resuming the parent, mark it stopped. */
5054 if (follow_child
&& !detach_fork
&& !non_stop
&& !sched_multi
)
5055 parent
->set_running (false);
5057 /* If resuming the child, mark it running. */
5058 if (follow_child
|| (!detach_fork
&& (non_stop
|| sched_multi
)))
5059 child
->set_running (true);
5061 /* In non-stop mode, also resume the other branch. */
5062 if (!detach_fork
&& (non_stop
5063 || (sched_multi
&& target_is_non_stop_p ())))
5066 switch_to_thread (parent
);
5068 switch_to_thread (child
);
5070 ecs
->event_thread
= inferior_thread ();
5071 ecs
->ptid
= inferior_ptid
;
5076 switch_to_thread (child
);
5078 switch_to_thread (parent
);
5080 ecs
->event_thread
= inferior_thread ();
5081 ecs
->ptid
= inferior_ptid
;
5089 process_event_stop_test (ecs
);
5092 case TARGET_WAITKIND_VFORK_DONE
:
5093 /* Done with the shared memory region. Re-insert breakpoints in
5094 the parent, and keep going. */
5096 context_switch (ecs
);
5098 current_inferior ()->waiting_for_vfork_done
= 0;
5099 current_inferior ()->pspace
->breakpoints_not_allowed
= 0;
5101 if (handle_stop_requested (ecs
))
5104 /* This also takes care of reinserting breakpoints in the
5105 previously locked inferior. */
5109 case TARGET_WAITKIND_EXECD
:
5111 /* Note we can't read registers yet (the stop_pc), because we
5112 don't yet know the inferior's post-exec architecture.
5113 'stop_pc' is explicitly read below instead. */
5114 switch_to_thread_no_regs (ecs
->event_thread
);
5116 /* Do whatever is necessary to the parent branch of the vfork. */
5117 handle_vfork_child_exec_or_exit (1);
5119 /* This causes the eventpoints and symbol table to be reset.
5120 Must do this now, before trying to determine whether to
5122 follow_exec (inferior_ptid
, ecs
->ws
.value
.execd_pathname
);
5124 /* In follow_exec we may have deleted the original thread and
5125 created a new one. Make sure that the event thread is the
5126 execd thread for that case (this is a nop otherwise). */
5127 ecs
->event_thread
= inferior_thread ();
5129 ecs
->event_thread
->suspend
.stop_pc
5130 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
5132 ecs
->event_thread
->control
.stop_bpstat
5133 = bpstat_stop_status (get_current_regcache ()->aspace (),
5134 ecs
->event_thread
->suspend
.stop_pc
,
5135 ecs
->event_thread
, &ecs
->ws
);
5137 /* Note that this may be referenced from inside
5138 bpstat_stop_status above, through inferior_has_execd. */
5139 xfree (ecs
->ws
.value
.execd_pathname
);
5140 ecs
->ws
.value
.execd_pathname
= NULL
;
5142 if (handle_stop_requested (ecs
))
5145 /* If no catchpoint triggered for this, then keep going. */
5146 if (!bpstat_causes_stop (ecs
->event_thread
->control
.stop_bpstat
))
5148 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5152 process_event_stop_test (ecs
);
5155 /* Be careful not to try to gather much state about a thread
5156 that's in a syscall. It's frequently a losing proposition. */
5157 case TARGET_WAITKIND_SYSCALL_ENTRY
:
5158 /* Getting the current syscall number. */
5159 if (handle_syscall_event (ecs
) == 0)
5160 process_event_stop_test (ecs
);
5163 /* Before examining the threads further, step this thread to
5164 get it entirely out of the syscall. (We get notice of the
5165 event when the thread is just on the verge of exiting a
5166 syscall. Stepping one instruction seems to get it back
5168 case TARGET_WAITKIND_SYSCALL_RETURN
:
5169 if (handle_syscall_event (ecs
) == 0)
5170 process_event_stop_test (ecs
);
5173 case TARGET_WAITKIND_STOPPED
:
5174 handle_signal_stop (ecs
);
5177 case TARGET_WAITKIND_NO_HISTORY
:
5178 /* Reverse execution: target ran out of history info. */
5180 /* Switch to the stopped thread. */
5181 context_switch (ecs
);
5183 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped\n");
5185 delete_just_stopped_threads_single_step_breakpoints ();
5186 ecs
->event_thread
->suspend
.stop_pc
5187 = regcache_read_pc (get_thread_regcache (inferior_thread ()));
5189 if (handle_stop_requested (ecs
))
5192 gdb::observers::no_history
.notify ();
5198 /* Restart threads back to what they were trying to do back when we
5199 paused them for an in-line step-over. The EVENT_THREAD thread is
5203 restart_threads (struct thread_info
*event_thread
)
5205 /* In case the instruction just stepped spawned a new thread. */
5206 update_thread_list ();
5208 for (thread_info
*tp
: all_non_exited_threads ())
5210 if (tp
== event_thread
)
5213 fprintf_unfiltered (gdb_stdlog
,
5214 "infrun: restart threads: "
5215 "[%s] is event thread\n",
5216 target_pid_to_str (tp
->ptid
).c_str ());
5220 if (!(tp
->state
== THREAD_RUNNING
|| tp
->control
.in_infcall
))
5223 fprintf_unfiltered (gdb_stdlog
,
5224 "infrun: restart threads: "
5225 "[%s] not meant to be running\n",
5226 target_pid_to_str (tp
->ptid
).c_str ());
5233 fprintf_unfiltered (gdb_stdlog
,
5234 "infrun: restart threads: [%s] resumed\n",
5235 target_pid_to_str (tp
->ptid
).c_str ());
5236 gdb_assert (tp
->executing
|| tp
->suspend
.waitstatus_pending_p
);
5240 if (thread_is_in_step_over_chain (tp
))
5243 fprintf_unfiltered (gdb_stdlog
,
5244 "infrun: restart threads: "
5245 "[%s] needs step-over\n",
5246 target_pid_to_str (tp
->ptid
).c_str ());
5247 gdb_assert (!tp
->resumed
);
5252 if (tp
->suspend
.waitstatus_pending_p
)
5255 fprintf_unfiltered (gdb_stdlog
,
5256 "infrun: restart threads: "
5257 "[%s] has pending status\n",
5258 target_pid_to_str (tp
->ptid
).c_str ());
5263 gdb_assert (!tp
->stop_requested
);
5265 /* If some thread needs to start a step-over at this point, it
5266 should still be in the step-over queue, and thus skipped
5268 if (thread_still_needs_step_over (tp
))
5270 internal_error (__FILE__
, __LINE__
,
5271 "thread [%s] needs a step-over, but not in "
5272 "step-over queue\n",
5273 target_pid_to_str (tp
->ptid
).c_str ());
5276 if (currently_stepping (tp
))
5279 fprintf_unfiltered (gdb_stdlog
,
5280 "infrun: restart threads: [%s] was stepping\n",
5281 target_pid_to_str (tp
->ptid
).c_str ());
5282 keep_going_stepped_thread (tp
);
5286 struct execution_control_state ecss
;
5287 struct execution_control_state
*ecs
= &ecss
;
5290 fprintf_unfiltered (gdb_stdlog
,
5291 "infrun: restart threads: [%s] continuing\n",
5292 target_pid_to_str (tp
->ptid
).c_str ());
5293 reset_ecs (ecs
, tp
);
5294 switch_to_thread (tp
);
5295 keep_going_pass_signal (ecs
);
5300 /* Callback for iterate_over_threads. Find a resumed thread that has
5301 a pending waitstatus. */
5304 resumed_thread_with_pending_status (struct thread_info
*tp
,
5308 && tp
->suspend
.waitstatus_pending_p
);
5311 /* Called when we get an event that may finish an in-line or
5312 out-of-line (displaced stepping) step-over started previously.
5313 Return true if the event is processed and we should go back to the
5314 event loop; false if the caller should continue processing the
5318 finish_step_over (struct execution_control_state
*ecs
)
5320 int had_step_over_info
;
5322 displaced_step_fixup (ecs
->event_thread
,
5323 ecs
->event_thread
->suspend
.stop_signal
);
5325 had_step_over_info
= step_over_info_valid_p ();
5327 if (had_step_over_info
)
5329 /* If we're stepping over a breakpoint with all threads locked,
5330 then only the thread that was stepped should be reporting
5332 gdb_assert (ecs
->event_thread
->control
.trap_expected
);
5334 clear_step_over_info ();
5337 if (!target_is_non_stop_p ())
5340 /* Start a new step-over in another thread if there's one that
5344 /* If we were stepping over a breakpoint before, and haven't started
5345 a new in-line step-over sequence, then restart all other threads
5346 (except the event thread). We can't do this in all-stop, as then
5347 e.g., we wouldn't be able to issue any other remote packet until
5348 these other threads stop. */
5349 if (had_step_over_info
&& !step_over_info_valid_p ())
5351 struct thread_info
*pending
;
5353 /* If we only have threads with pending statuses, the restart
5354 below won't restart any thread and so nothing re-inserts the
5355 breakpoint we just stepped over. But we need it inserted
5356 when we later process the pending events, otherwise if
5357 another thread has a pending event for this breakpoint too,
5358 we'd discard its event (because the breakpoint that
5359 originally caused the event was no longer inserted). */
5360 context_switch (ecs
);
5361 insert_breakpoints ();
5364 scoped_restore save_defer_tc
5365 = make_scoped_defer_target_commit_resume ();
5366 restart_threads (ecs
->event_thread
);
5368 target_commit_resume ();
5370 /* If we have events pending, go through handle_inferior_event
5371 again, picking up a pending event at random. This avoids
5372 thread starvation. */
5374 /* But not if we just stepped over a watchpoint in order to let
5375 the instruction execute so we can evaluate its expression.
5376 The set of watchpoints that triggered is recorded in the
5377 breakpoint objects themselves (see bp->watchpoint_triggered).
5378 If we processed another event first, that other event could
5379 clobber this info. */
5380 if (ecs
->event_thread
->stepping_over_watchpoint
)
5383 pending
= iterate_over_threads (resumed_thread_with_pending_status
,
5385 if (pending
!= NULL
)
5387 struct thread_info
*tp
= ecs
->event_thread
;
5388 struct regcache
*regcache
;
5392 fprintf_unfiltered (gdb_stdlog
,
5393 "infrun: found resumed threads with "
5394 "pending events, saving status\n");
5397 gdb_assert (pending
!= tp
);
5399 /* Record the event thread's event for later. */
5400 save_waitstatus (tp
, &ecs
->ws
);
5401 /* This was cleared early, by handle_inferior_event. Set it
5402 so this pending event is considered by
5406 gdb_assert (!tp
->executing
);
5408 regcache
= get_thread_regcache (tp
);
5409 tp
->suspend
.stop_pc
= regcache_read_pc (regcache
);
5413 fprintf_unfiltered (gdb_stdlog
,
5414 "infrun: saved stop_pc=%s for %s "
5415 "(currently_stepping=%d)\n",
5416 paddress (target_gdbarch (),
5417 tp
->suspend
.stop_pc
),
5418 target_pid_to_str (tp
->ptid
).c_str (),
5419 currently_stepping (tp
));
5422 /* This in-line step-over finished; clear this so we won't
5423 start a new one. This is what handle_signal_stop would
5424 do, if we returned false. */
5425 tp
->stepping_over_breakpoint
= 0;
5427 /* Wake up the event loop again. */
5428 mark_async_event_handler (infrun_async_inferior_event_token
);
5430 prepare_to_wait (ecs
);
5438 /* Come here when the program has stopped with a signal. */
5441 handle_signal_stop (struct execution_control_state
*ecs
)
5443 struct frame_info
*frame
;
5444 struct gdbarch
*gdbarch
;
5445 int stopped_by_watchpoint
;
5446 enum stop_kind stop_soon
;
5449 gdb_assert (ecs
->ws
.kind
== TARGET_WAITKIND_STOPPED
);
5451 ecs
->event_thread
->suspend
.stop_signal
= ecs
->ws
.value
.sig
;
5453 /* Do we need to clean up the state of a thread that has
5454 completed a displaced single-step? (Doing so usually affects
5455 the PC, so do it here, before we set stop_pc.) */
5456 if (finish_step_over (ecs
))
5459 /* If we either finished a single-step or hit a breakpoint, but
5460 the user wanted this thread to be stopped, pretend we got a
5461 SIG0 (generic unsignaled stop). */
5462 if (ecs
->event_thread
->stop_requested
5463 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5464 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5466 ecs
->event_thread
->suspend
.stop_pc
5467 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
5471 struct regcache
*regcache
= get_thread_regcache (ecs
->event_thread
);
5472 struct gdbarch
*reg_gdbarch
= regcache
->arch ();
5473 scoped_restore save_inferior_ptid
= make_scoped_restore (&inferior_ptid
);
5475 inferior_ptid
= ecs
->ptid
;
5477 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_pc = %s\n",
5478 paddress (reg_gdbarch
,
5479 ecs
->event_thread
->suspend
.stop_pc
));
5480 if (target_stopped_by_watchpoint ())
5484 fprintf_unfiltered (gdb_stdlog
, "infrun: stopped by watchpoint\n");
5486 if (target_stopped_data_address (current_top_target (), &addr
))
5487 fprintf_unfiltered (gdb_stdlog
,
5488 "infrun: stopped data address = %s\n",
5489 paddress (reg_gdbarch
, addr
));
5491 fprintf_unfiltered (gdb_stdlog
,
5492 "infrun: (no data address available)\n");
5496 /* This is originated from start_remote(), start_inferior() and
5497 shared libraries hook functions. */
5498 stop_soon
= get_inferior_stop_soon (ecs
);
5499 if (stop_soon
== STOP_QUIETLY
|| stop_soon
== STOP_QUIETLY_REMOTE
)
5501 context_switch (ecs
);
5503 fprintf_unfiltered (gdb_stdlog
, "infrun: quietly stopped\n");
5504 stop_print_frame
= 1;
5509 /* This originates from attach_command(). We need to overwrite
5510 the stop_signal here, because some kernels don't ignore a
5511 SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
5512 See more comments in inferior.h. On the other hand, if we
5513 get a non-SIGSTOP, report it to the user - assume the backend
5514 will handle the SIGSTOP if it should show up later.
5516 Also consider that the attach is complete when we see a
5517 SIGTRAP. Some systems (e.g. Windows), and stubs supporting
5518 target extended-remote report it instead of a SIGSTOP
5519 (e.g. gdbserver). We already rely on SIGTRAP being our
5520 signal, so this is no exception.
5522 Also consider that the attach is complete when we see a
5523 GDB_SIGNAL_0. In non-stop mode, GDB will explicitly tell
5524 the target to stop all threads of the inferior, in case the
5525 low level attach operation doesn't stop them implicitly. If
5526 they weren't stopped implicitly, then the stub will report a
5527 GDB_SIGNAL_0, meaning: stopped for no particular reason
5528 other than GDB's request. */
5529 if (stop_soon
== STOP_QUIETLY_NO_SIGSTOP
5530 && (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_STOP
5531 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5532 || ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_0
))
5534 stop_print_frame
= 1;
5536 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5540 /* See if something interesting happened to the non-current thread. If
5541 so, then switch to that thread. */
5542 if (ecs
->ptid
!= inferior_ptid
)
5545 fprintf_unfiltered (gdb_stdlog
, "infrun: context switch\n");
5547 context_switch (ecs
);
5549 if (deprecated_context_hook
)
5550 deprecated_context_hook (ecs
->event_thread
->global_num
);
5553 /* At this point, get hold of the now-current thread's frame. */
5554 frame
= get_current_frame ();
5555 gdbarch
= get_frame_arch (frame
);
5557 /* Pull the single step breakpoints out of the target. */
5558 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
5560 struct regcache
*regcache
;
5563 regcache
= get_thread_regcache (ecs
->event_thread
);
5564 const address_space
*aspace
= regcache
->aspace ();
5566 pc
= regcache_read_pc (regcache
);
5568 /* However, before doing so, if this single-step breakpoint was
5569 actually for another thread, set this thread up for moving
5571 if (!thread_has_single_step_breakpoint_here (ecs
->event_thread
,
5574 if (single_step_breakpoint_inserted_here_p (aspace
, pc
))
5578 fprintf_unfiltered (gdb_stdlog
,
5579 "infrun: [%s] hit another thread's "
5580 "single-step breakpoint\n",
5581 target_pid_to_str (ecs
->ptid
).c_str ());
5583 ecs
->hit_singlestep_breakpoint
= 1;
5590 fprintf_unfiltered (gdb_stdlog
,
5591 "infrun: [%s] hit its "
5592 "single-step breakpoint\n",
5593 target_pid_to_str (ecs
->ptid
).c_str ());
5597 delete_just_stopped_threads_single_step_breakpoints ();
5599 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5600 && ecs
->event_thread
->control
.trap_expected
5601 && ecs
->event_thread
->stepping_over_watchpoint
)
5602 stopped_by_watchpoint
= 0;
5604 stopped_by_watchpoint
= watchpoints_triggered (&ecs
->ws
);
5606 /* If necessary, step over this watchpoint. We'll be back to display
5608 if (stopped_by_watchpoint
5609 && (target_have_steppable_watchpoint
5610 || gdbarch_have_nonsteppable_watchpoint (gdbarch
)))
5612 /* At this point, we are stopped at an instruction which has
5613 attempted to write to a piece of memory under control of
5614 a watchpoint. The instruction hasn't actually executed
5615 yet. If we were to evaluate the watchpoint expression
5616 now, we would get the old value, and therefore no change
5617 would seem to have occurred.
5619 In order to make watchpoints work `right', we really need
5620 to complete the memory write, and then evaluate the
5621 watchpoint expression. We do this by single-stepping the
5624 It may not be necessary to disable the watchpoint to step over
5625 it. For example, the PA can (with some kernel cooperation)
5626 single step over a watchpoint without disabling the watchpoint.
5628 It is far more common to need to disable a watchpoint to step
5629 the inferior over it. If we have non-steppable watchpoints,
5630 we must disable the current watchpoint; it's simplest to
5631 disable all watchpoints.
5633 Any breakpoint at PC must also be stepped over -- if there's
5634 one, it will have already triggered before the watchpoint
5635 triggered, and we either already reported it to the user, or
5636 it didn't cause a stop and we called keep_going. In either
5637 case, if there was a breakpoint at PC, we must be trying to
5639 ecs
->event_thread
->stepping_over_watchpoint
= 1;
5644 ecs
->event_thread
->stepping_over_breakpoint
= 0;
5645 ecs
->event_thread
->stepping_over_watchpoint
= 0;
5646 bpstat_clear (&ecs
->event_thread
->control
.stop_bpstat
);
5647 ecs
->event_thread
->control
.stop_step
= 0;
5648 stop_print_frame
= 1;
5649 stopped_by_random_signal
= 0;
5650 bpstat stop_chain
= NULL
;
5652 /* Hide inlined functions starting here, unless we just performed stepi or
5653 nexti. After stepi and nexti, always show the innermost frame (not any
5654 inline function call sites). */
5655 if (ecs
->event_thread
->control
.step_range_end
!= 1)
5657 const address_space
*aspace
5658 = get_thread_regcache (ecs
->event_thread
)->aspace ();
5660 /* skip_inline_frames is expensive, so we avoid it if we can
5661 determine that the address is one where functions cannot have
5662 been inlined. This improves performance with inferiors that
5663 load a lot of shared libraries, because the solib event
5664 breakpoint is defined as the address of a function (i.e. not
5665 inline). Note that we have to check the previous PC as well
5666 as the current one to catch cases when we have just
5667 single-stepped off a breakpoint prior to reinstating it.
5668 Note that we're assuming that the code we single-step to is
5669 not inline, but that's not definitive: there's nothing
5670 preventing the event breakpoint function from containing
5671 inlined code, and the single-step ending up there. If the
5672 user had set a breakpoint on that inlined code, the missing
5673 skip_inline_frames call would break things. Fortunately
5674 that's an extremely unlikely scenario. */
5675 if (!pc_at_non_inline_function (aspace
,
5676 ecs
->event_thread
->suspend
.stop_pc
,
5678 && !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5679 && ecs
->event_thread
->control
.trap_expected
5680 && pc_at_non_inline_function (aspace
,
5681 ecs
->event_thread
->prev_pc
,
5684 stop_chain
= build_bpstat_chain (aspace
,
5685 ecs
->event_thread
->suspend
.stop_pc
,
5687 skip_inline_frames (ecs
->event_thread
, stop_chain
);
5689 /* Re-fetch current thread's frame in case that invalidated
5691 frame
= get_current_frame ();
5692 gdbarch
= get_frame_arch (frame
);
5696 if (ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5697 && ecs
->event_thread
->control
.trap_expected
5698 && gdbarch_single_step_through_delay_p (gdbarch
)
5699 && currently_stepping (ecs
->event_thread
))
5701 /* We're trying to step off a breakpoint. Turns out that we're
5702 also on an instruction that needs to be stepped multiple
5703 times before it's been fully executing. E.g., architectures
5704 with a delay slot. It needs to be stepped twice, once for
5705 the instruction and once for the delay slot. */
5706 int step_through_delay
5707 = gdbarch_single_step_through_delay (gdbarch
, frame
);
5709 if (debug_infrun
&& step_through_delay
)
5710 fprintf_unfiltered (gdb_stdlog
, "infrun: step through delay\n");
5711 if (ecs
->event_thread
->control
.step_range_end
== 0
5712 && step_through_delay
)
5714 /* The user issued a continue when stopped at a breakpoint.
5715 Set up for another trap and get out of here. */
5716 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5720 else if (step_through_delay
)
5722 /* The user issued a step when stopped at a breakpoint.
5723 Maybe we should stop, maybe we should not - the delay
5724 slot *might* correspond to a line of source. In any
5725 case, don't decide that here, just set
5726 ecs->stepping_over_breakpoint, making sure we
5727 single-step again before breakpoints are re-inserted. */
5728 ecs
->event_thread
->stepping_over_breakpoint
= 1;
5732 /* See if there is a breakpoint/watchpoint/catchpoint/etc. that
5733 handles this event. */
5734 ecs
->event_thread
->control
.stop_bpstat
5735 = bpstat_stop_status (get_current_regcache ()->aspace (),
5736 ecs
->event_thread
->suspend
.stop_pc
,
5737 ecs
->event_thread
, &ecs
->ws
, stop_chain
);
5739 /* Following in case break condition called a
5741 stop_print_frame
= 1;
5743 /* This is where we handle "moribund" watchpoints. Unlike
5744 software breakpoints traps, hardware watchpoint traps are
5745 always distinguishable from random traps. If no high-level
5746 watchpoint is associated with the reported stop data address
5747 anymore, then the bpstat does not explain the signal ---
5748 simply make sure to ignore it if `stopped_by_watchpoint' is
5752 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5753 && !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5755 && stopped_by_watchpoint
)
5756 fprintf_unfiltered (gdb_stdlog
,
5757 "infrun: no user watchpoint explains "
5758 "watchpoint SIGTRAP, ignoring\n");
5760 /* NOTE: cagney/2003-03-29: These checks for a random signal
5761 at one stage in the past included checks for an inferior
5762 function call's call dummy's return breakpoint. The original
5763 comment, that went with the test, read:
5765 ``End of a stack dummy. Some systems (e.g. Sony news) give
5766 another signal besides SIGTRAP, so check here as well as
5769 If someone ever tries to get call dummys on a
5770 non-executable stack to work (where the target would stop
5771 with something like a SIGSEGV), then those tests might need
5772 to be re-instated. Given, however, that the tests were only
5773 enabled when momentary breakpoints were not being used, I
5774 suspect that it won't be the case.
5776 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
5777 be necessary for call dummies on a non-executable stack on
5780 /* See if the breakpoints module can explain the signal. */
5782 = !bpstat_explains_signal (ecs
->event_thread
->control
.stop_bpstat
,
5783 ecs
->event_thread
->suspend
.stop_signal
);
5785 /* Maybe this was a trap for a software breakpoint that has since
5787 if (random_signal
&& target_stopped_by_sw_breakpoint ())
5789 if (program_breakpoint_here_p (gdbarch
,
5790 ecs
->event_thread
->suspend
.stop_pc
))
5792 struct regcache
*regcache
;
5795 /* Re-adjust PC to what the program would see if GDB was not
5797 regcache
= get_thread_regcache (ecs
->event_thread
);
5798 decr_pc
= gdbarch_decr_pc_after_break (gdbarch
);
5801 gdb::optional
<scoped_restore_tmpl
<int>>
5802 restore_operation_disable
;
5804 if (record_full_is_used ())
5805 restore_operation_disable
.emplace
5806 (record_full_gdb_operation_disable_set ());
5808 regcache_write_pc (regcache
,
5809 ecs
->event_thread
->suspend
.stop_pc
+ decr_pc
);
5814 /* A delayed software breakpoint event. Ignore the trap. */
5816 fprintf_unfiltered (gdb_stdlog
,
5817 "infrun: delayed software breakpoint "
5818 "trap, ignoring\n");
5823 /* Maybe this was a trap for a hardware breakpoint/watchpoint that
5824 has since been removed. */
5825 if (random_signal
&& target_stopped_by_hw_breakpoint ())
5827 /* A delayed hardware breakpoint event. Ignore the trap. */
5829 fprintf_unfiltered (gdb_stdlog
,
5830 "infrun: delayed hardware breakpoint/watchpoint "
5831 "trap, ignoring\n");
5835 /* If not, perhaps stepping/nexting can. */
5837 random_signal
= !(ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
5838 && currently_stepping (ecs
->event_thread
));
5840 /* Perhaps the thread hit a single-step breakpoint of _another_
5841 thread. Single-step breakpoints are transparent to the
5842 breakpoints module. */
5844 random_signal
= !ecs
->hit_singlestep_breakpoint
;
5846 /* No? Perhaps we got a moribund watchpoint. */
5848 random_signal
= !stopped_by_watchpoint
;
5850 /* Always stop if the user explicitly requested this thread to
5852 if (ecs
->event_thread
->stop_requested
)
5856 fprintf_unfiltered (gdb_stdlog
, "infrun: user-requested stop\n");
5859 /* For the program's own signals, act according to
5860 the signal handling tables. */
5864 /* Signal not for debugging purposes. */
5865 struct inferior
*inf
= find_inferior_ptid (ecs
->ptid
);
5866 enum gdb_signal stop_signal
= ecs
->event_thread
->suspend
.stop_signal
;
5869 fprintf_unfiltered (gdb_stdlog
, "infrun: random signal (%s)\n",
5870 gdb_signal_to_symbol_string (stop_signal
));
5872 stopped_by_random_signal
= 1;
5874 /* Always stop on signals if we're either just gaining control
5875 of the program, or the user explicitly requested this thread
5876 to remain stopped. */
5877 if (stop_soon
!= NO_STOP_QUIETLY
5878 || ecs
->event_thread
->stop_requested
5880 && signal_stop_state (ecs
->event_thread
->suspend
.stop_signal
)))
5886 /* Notify observers the signal has "handle print" set. Note we
5887 returned early above if stopping; normal_stop handles the
5888 printing in that case. */
5889 if (signal_print
[ecs
->event_thread
->suspend
.stop_signal
])
5891 /* The signal table tells us to print about this signal. */
5892 target_terminal::ours_for_output ();
5893 gdb::observers::signal_received
.notify (ecs
->event_thread
->suspend
.stop_signal
);
5894 target_terminal::inferior ();
5897 /* Clear the signal if it should not be passed. */
5898 if (signal_program
[ecs
->event_thread
->suspend
.stop_signal
] == 0)
5899 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
5901 if (ecs
->event_thread
->prev_pc
== ecs
->event_thread
->suspend
.stop_pc
5902 && ecs
->event_thread
->control
.trap_expected
5903 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
5905 /* We were just starting a new sequence, attempting to
5906 single-step off of a breakpoint and expecting a SIGTRAP.
5907 Instead this signal arrives. This signal will take us out
5908 of the stepping range so GDB needs to remember to, when
5909 the signal handler returns, resume stepping off that
5911 /* To simplify things, "continue" is forced to use the same
5912 code paths as single-step - set a breakpoint at the
5913 signal return address and then, once hit, step off that
5916 fprintf_unfiltered (gdb_stdlog
,
5917 "infrun: signal arrived while stepping over "
5920 insert_hp_step_resume_breakpoint_at_frame (frame
);
5921 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
5922 /* Reset trap_expected to ensure breakpoints are re-inserted. */
5923 ecs
->event_thread
->control
.trap_expected
= 0;
5925 /* If we were nexting/stepping some other thread, switch to
5926 it, so that we don't continue it, losing control. */
5927 if (!switch_back_to_stepped_thread (ecs
))
5932 if (ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_0
5933 && (pc_in_thread_step_range (ecs
->event_thread
->suspend
.stop_pc
,
5935 || ecs
->event_thread
->control
.step_range_end
== 1)
5936 && frame_id_eq (get_stack_frame_id (frame
),
5937 ecs
->event_thread
->control
.step_stack_frame_id
)
5938 && ecs
->event_thread
->control
.step_resume_breakpoint
== NULL
)
5940 /* The inferior is about to take a signal that will take it
5941 out of the single step range. Set a breakpoint at the
5942 current PC (which is presumably where the signal handler
5943 will eventually return) and then allow the inferior to
5946 Note that this is only needed for a signal delivered
5947 while in the single-step range. Nested signals aren't a
5948 problem as they eventually all return. */
5950 fprintf_unfiltered (gdb_stdlog
,
5951 "infrun: signal may take us out of "
5952 "single-step range\n");
5954 clear_step_over_info ();
5955 insert_hp_step_resume_breakpoint_at_frame (frame
);
5956 ecs
->event_thread
->step_after_step_resume_breakpoint
= 1;
5957 /* Reset trap_expected to ensure breakpoints are re-inserted. */
5958 ecs
->event_thread
->control
.trap_expected
= 0;
5963 /* Note: step_resume_breakpoint may be non-NULL. This occurs
5964 when either there's a nested signal, or when there's a
5965 pending signal enabled just as the signal handler returns
5966 (leaving the inferior at the step-resume-breakpoint without
5967 actually executing it). Either way continue until the
5968 breakpoint is really hit. */
5970 if (!switch_back_to_stepped_thread (ecs
))
5973 fprintf_unfiltered (gdb_stdlog
,
5974 "infrun: random signal, keep going\n");
5981 process_event_stop_test (ecs
);
5984 /* Come here when we've got some debug event / signal we can explain
5985 (IOW, not a random signal), and test whether it should cause a
5986 stop, or whether we should resume the inferior (transparently).
5987 E.g., could be a breakpoint whose condition evaluates false; we
5988 could be still stepping within the line; etc. */
5991 process_event_stop_test (struct execution_control_state
*ecs
)
5993 struct symtab_and_line stop_pc_sal
;
5994 struct frame_info
*frame
;
5995 struct gdbarch
*gdbarch
;
5996 CORE_ADDR jmp_buf_pc
;
5997 struct bpstat_what what
;
5999 /* Handle cases caused by hitting a breakpoint. */
6001 frame
= get_current_frame ();
6002 gdbarch
= get_frame_arch (frame
);
6004 what
= bpstat_what (ecs
->event_thread
->control
.stop_bpstat
);
6006 if (what
.call_dummy
)
6008 stop_stack_dummy
= what
.call_dummy
;
6011 /* A few breakpoint types have callbacks associated (e.g.,
6012 bp_jit_event). Run them now. */
6013 bpstat_run_callbacks (ecs
->event_thread
->control
.stop_bpstat
);
6015 /* If we hit an internal event that triggers symbol changes, the
6016 current frame will be invalidated within bpstat_what (e.g., if we
6017 hit an internal solib event). Re-fetch it. */
6018 frame
= get_current_frame ();
6019 gdbarch
= get_frame_arch (frame
);
6021 switch (what
.main_action
)
6023 case BPSTAT_WHAT_SET_LONGJMP_RESUME
:
6024 /* If we hit the breakpoint at longjmp while stepping, we
6025 install a momentary breakpoint at the target of the
6029 fprintf_unfiltered (gdb_stdlog
,
6030 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
6032 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6034 if (what
.is_longjmp
)
6036 struct value
*arg_value
;
6038 /* If we set the longjmp breakpoint via a SystemTap probe,
6039 then use it to extract the arguments. The destination PC
6040 is the third argument to the probe. */
6041 arg_value
= probe_safe_evaluate_at_pc (frame
, 2);
6044 jmp_buf_pc
= value_as_address (arg_value
);
6045 jmp_buf_pc
= gdbarch_addr_bits_remove (gdbarch
, jmp_buf_pc
);
6047 else if (!gdbarch_get_longjmp_target_p (gdbarch
)
6048 || !gdbarch_get_longjmp_target (gdbarch
,
6049 frame
, &jmp_buf_pc
))
6052 fprintf_unfiltered (gdb_stdlog
,
6053 "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME "
6054 "(!gdbarch_get_longjmp_target)\n");
6059 /* Insert a breakpoint at resume address. */
6060 insert_longjmp_resume_breakpoint (gdbarch
, jmp_buf_pc
);
6063 check_exception_resume (ecs
, frame
);
6067 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
:
6069 struct frame_info
*init_frame
;
6071 /* There are several cases to consider.
6073 1. The initiating frame no longer exists. In this case we
6074 must stop, because the exception or longjmp has gone too
6077 2. The initiating frame exists, and is the same as the
6078 current frame. We stop, because the exception or longjmp
6081 3. The initiating frame exists and is different from the
6082 current frame. This means the exception or longjmp has
6083 been caught beneath the initiating frame, so keep going.
6085 4. longjmp breakpoint has been placed just to protect
6086 against stale dummy frames and user is not interested in
6087 stopping around longjmps. */
6090 fprintf_unfiltered (gdb_stdlog
,
6091 "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
6093 gdb_assert (ecs
->event_thread
->control
.exception_resume_breakpoint
6095 delete_exception_resume_breakpoint (ecs
->event_thread
);
6097 if (what
.is_longjmp
)
6099 check_longjmp_breakpoint_for_call_dummy (ecs
->event_thread
);
6101 if (!frame_id_p (ecs
->event_thread
->initiating_frame
))
6109 init_frame
= frame_find_by_id (ecs
->event_thread
->initiating_frame
);
6113 struct frame_id current_id
6114 = get_frame_id (get_current_frame ());
6115 if (frame_id_eq (current_id
,
6116 ecs
->event_thread
->initiating_frame
))
6118 /* Case 2. Fall through. */
6128 /* For Cases 1 and 2, remove the step-resume breakpoint, if it
6130 delete_step_resume_breakpoint (ecs
->event_thread
);
6132 end_stepping_range (ecs
);
6136 case BPSTAT_WHAT_SINGLE
:
6138 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_SINGLE\n");
6139 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6140 /* Still need to check other stuff, at least the case where we
6141 are stepping and step out of the right range. */
6144 case BPSTAT_WHAT_STEP_RESUME
:
6146 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
6148 delete_step_resume_breakpoint (ecs
->event_thread
);
6149 if (ecs
->event_thread
->control
.proceed_to_finish
6150 && execution_direction
== EXEC_REVERSE
)
6152 struct thread_info
*tp
= ecs
->event_thread
;
6154 /* We are finishing a function in reverse, and just hit the
6155 step-resume breakpoint at the start address of the
6156 function, and we're almost there -- just need to back up
6157 by one more single-step, which should take us back to the
6159 tp
->control
.step_range_start
= tp
->control
.step_range_end
= 1;
6163 fill_in_stop_func (gdbarch
, ecs
);
6164 if (ecs
->event_thread
->suspend
.stop_pc
== ecs
->stop_func_start
6165 && execution_direction
== EXEC_REVERSE
)
6167 /* We are stepping over a function call in reverse, and just
6168 hit the step-resume breakpoint at the start address of
6169 the function. Go back to single-stepping, which should
6170 take us back to the function call. */
6171 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6177 case BPSTAT_WHAT_STOP_NOISY
:
6179 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
6180 stop_print_frame
= 1;
6182 /* Assume the thread stopped for a breapoint. We'll still check
6183 whether a/the breakpoint is there when the thread is next
6185 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6190 case BPSTAT_WHAT_STOP_SILENT
:
6192 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
6193 stop_print_frame
= 0;
6195 /* Assume the thread stopped for a breapoint. We'll still check
6196 whether a/the breakpoint is there when the thread is next
6198 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6202 case BPSTAT_WHAT_HP_STEP_RESUME
:
6204 fprintf_unfiltered (gdb_stdlog
, "infrun: BPSTAT_WHAT_HP_STEP_RESUME\n");
6206 delete_step_resume_breakpoint (ecs
->event_thread
);
6207 if (ecs
->event_thread
->step_after_step_resume_breakpoint
)
6209 /* Back when the step-resume breakpoint was inserted, we
6210 were trying to single-step off a breakpoint. Go back to
6212 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6213 ecs
->event_thread
->stepping_over_breakpoint
= 1;
6219 case BPSTAT_WHAT_KEEP_CHECKING
:
6223 /* If we stepped a permanent breakpoint and we had a high priority
6224 step-resume breakpoint for the address we stepped, but we didn't
6225 hit it, then we must have stepped into the signal handler. The
6226 step-resume was only necessary to catch the case of _not_
6227 stepping into the handler, so delete it, and fall through to
6228 checking whether the step finished. */
6229 if (ecs
->event_thread
->stepped_breakpoint
)
6231 struct breakpoint
*sr_bp
6232 = ecs
->event_thread
->control
.step_resume_breakpoint
;
6235 && sr_bp
->loc
->permanent
6236 && sr_bp
->type
== bp_hp_step_resume
6237 && sr_bp
->loc
->address
== ecs
->event_thread
->prev_pc
)
6240 fprintf_unfiltered (gdb_stdlog
,
6241 "infrun: stepped permanent breakpoint, stopped in "
6243 delete_step_resume_breakpoint (ecs
->event_thread
);
6244 ecs
->event_thread
->step_after_step_resume_breakpoint
= 0;
6248 /* We come here if we hit a breakpoint but should not stop for it.
6249 Possibly we also were stepping and should stop for that. So fall
6250 through and test for stepping. But, if not stepping, do not
6253 /* In all-stop mode, if we're currently stepping but have stopped in
6254 some other thread, we need to switch back to the stepped thread. */
6255 if (switch_back_to_stepped_thread (ecs
))
6258 if (ecs
->event_thread
->control
.step_resume_breakpoint
)
6261 fprintf_unfiltered (gdb_stdlog
,
6262 "infrun: step-resume breakpoint is inserted\n");
6264 /* Having a step-resume breakpoint overrides anything
6265 else having to do with stepping commands until
6266 that breakpoint is reached. */
6271 if (ecs
->event_thread
->control
.step_range_end
== 0)
6274 fprintf_unfiltered (gdb_stdlog
, "infrun: no stepping, continue\n");
6275 /* Likewise if we aren't even stepping. */
6280 /* Re-fetch current thread's frame in case the code above caused
6281 the frame cache to be re-initialized, making our FRAME variable
6282 a dangling pointer. */
6283 frame
= get_current_frame ();
6284 gdbarch
= get_frame_arch (frame
);
6285 fill_in_stop_func (gdbarch
, ecs
);
6287 /* If stepping through a line, keep going if still within it.
6289 Note that step_range_end is the address of the first instruction
6290 beyond the step range, and NOT the address of the last instruction
6293 Note also that during reverse execution, we may be stepping
6294 through a function epilogue and therefore must detect when
6295 the current-frame changes in the middle of a line. */
6297 if (pc_in_thread_step_range (ecs
->event_thread
->suspend
.stop_pc
,
6299 && (execution_direction
!= EXEC_REVERSE
6300 || frame_id_eq (get_frame_id (frame
),
6301 ecs
->event_thread
->control
.step_frame_id
)))
6305 (gdb_stdlog
, "infrun: stepping inside range [%s-%s]\n",
6306 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_start
),
6307 paddress (gdbarch
, ecs
->event_thread
->control
.step_range_end
));
6309 /* Tentatively re-enable range stepping; `resume' disables it if
6310 necessary (e.g., if we're stepping over a breakpoint or we
6311 have software watchpoints). */
6312 ecs
->event_thread
->control
.may_range_step
= 1;
6314 /* When stepping backward, stop at beginning of line range
6315 (unless it's the function entry point, in which case
6316 keep going back to the call point). */
6317 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6318 if (stop_pc
== ecs
->event_thread
->control
.step_range_start
6319 && stop_pc
!= ecs
->stop_func_start
6320 && execution_direction
== EXEC_REVERSE
)
6321 end_stepping_range (ecs
);
6328 /* We stepped out of the stepping range. */
6330 /* If we are stepping at the source level and entered the runtime
6331 loader dynamic symbol resolution code...
6333 EXEC_FORWARD: we keep on single stepping until we exit the run
6334 time loader code and reach the callee's address.
6336 EXEC_REVERSE: we've already executed the callee (backward), and
6337 the runtime loader code is handled just like any other
6338 undebuggable function call. Now we need only keep stepping
6339 backward through the trampoline code, and that's handled further
6340 down, so there is nothing for us to do here. */
6342 if (execution_direction
!= EXEC_REVERSE
6343 && ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6344 && in_solib_dynsym_resolve_code (ecs
->event_thread
->suspend
.stop_pc
))
6346 CORE_ADDR pc_after_resolver
=
6347 gdbarch_skip_solib_resolver (gdbarch
,
6348 ecs
->event_thread
->suspend
.stop_pc
);
6351 fprintf_unfiltered (gdb_stdlog
,
6352 "infrun: stepped into dynsym resolve code\n");
6354 if (pc_after_resolver
)
6356 /* Set up a step-resume breakpoint at the address
6357 indicated by SKIP_SOLIB_RESOLVER. */
6358 symtab_and_line sr_sal
;
6359 sr_sal
.pc
= pc_after_resolver
;
6360 sr_sal
.pspace
= get_frame_program_space (frame
);
6362 insert_step_resume_breakpoint_at_sal (gdbarch
,
6363 sr_sal
, null_frame_id
);
6370 /* Step through an indirect branch thunk. */
6371 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6372 && gdbarch_in_indirect_branch_thunk (gdbarch
,
6373 ecs
->event_thread
->suspend
.stop_pc
))
6376 fprintf_unfiltered (gdb_stdlog
,
6377 "infrun: stepped into indirect branch thunk\n");
6382 if (ecs
->event_thread
->control
.step_range_end
!= 1
6383 && (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6384 || ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6385 && get_frame_type (frame
) == SIGTRAMP_FRAME
)
6388 fprintf_unfiltered (gdb_stdlog
,
6389 "infrun: stepped into signal trampoline\n");
6390 /* The inferior, while doing a "step" or "next", has ended up in
6391 a signal trampoline (either by a signal being delivered or by
6392 the signal handler returning). Just single-step until the
6393 inferior leaves the trampoline (either by calling the handler
6399 /* If we're in the return path from a shared library trampoline,
6400 we want to proceed through the trampoline when stepping. */
6401 /* macro/2012-04-25: This needs to come before the subroutine
6402 call check below as on some targets return trampolines look
6403 like subroutine calls (MIPS16 return thunks). */
6404 if (gdbarch_in_solib_return_trampoline (gdbarch
,
6405 ecs
->event_thread
->suspend
.stop_pc
,
6406 ecs
->stop_func_name
)
6407 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6409 /* Determine where this trampoline returns. */
6410 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6411 CORE_ADDR real_stop_pc
6412 = gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6415 fprintf_unfiltered (gdb_stdlog
,
6416 "infrun: stepped into solib return tramp\n");
6418 /* Only proceed through if we know where it's going. */
6421 /* And put the step-breakpoint there and go until there. */
6422 symtab_and_line sr_sal
;
6423 sr_sal
.pc
= real_stop_pc
;
6424 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
6425 sr_sal
.pspace
= get_frame_program_space (frame
);
6427 /* Do not specify what the fp should be when we stop since
6428 on some machines the prologue is where the new fp value
6430 insert_step_resume_breakpoint_at_sal (gdbarch
,
6431 sr_sal
, null_frame_id
);
6433 /* Restart without fiddling with the step ranges or
6440 /* Check for subroutine calls. The check for the current frame
6441 equalling the step ID is not necessary - the check of the
6442 previous frame's ID is sufficient - but it is a common case and
6443 cheaper than checking the previous frame's ID.
6445 NOTE: frame_id_eq will never report two invalid frame IDs as
6446 being equal, so to get into this block, both the current and
6447 previous frame must have valid frame IDs. */
6448 /* The outer_frame_id check is a heuristic to detect stepping
6449 through startup code. If we step over an instruction which
6450 sets the stack pointer from an invalid value to a valid value,
6451 we may detect that as a subroutine call from the mythical
6452 "outermost" function. This could be fixed by marking
6453 outermost frames as !stack_p,code_p,special_p. Then the
6454 initial outermost frame, before sp was valid, would
6455 have code_addr == &_start. See the comment in frame_id_eq
6457 if (!frame_id_eq (get_stack_frame_id (frame
),
6458 ecs
->event_thread
->control
.step_stack_frame_id
)
6459 && (frame_id_eq (frame_unwind_caller_id (get_current_frame ()),
6460 ecs
->event_thread
->control
.step_stack_frame_id
)
6461 && (!frame_id_eq (ecs
->event_thread
->control
.step_stack_frame_id
,
6463 || (ecs
->event_thread
->control
.step_start_function
6464 != find_pc_function (ecs
->event_thread
->suspend
.stop_pc
)))))
6466 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6467 CORE_ADDR real_stop_pc
;
6470 fprintf_unfiltered (gdb_stdlog
, "infrun: stepped into subroutine\n");
6472 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_NONE
)
6474 /* I presume that step_over_calls is only 0 when we're
6475 supposed to be stepping at the assembly language level
6476 ("stepi"). Just stop. */
6477 /* And this works the same backward as frontward. MVS */
6478 end_stepping_range (ecs
);
6482 /* Reverse stepping through solib trampolines. */
6484 if (execution_direction
== EXEC_REVERSE
6485 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
6486 && (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6487 || (ecs
->stop_func_start
== 0
6488 && in_solib_dynsym_resolve_code (stop_pc
))))
6490 /* Any solib trampoline code can be handled in reverse
6491 by simply continuing to single-step. We have already
6492 executed the solib function (backwards), and a few
6493 steps will take us back through the trampoline to the
6499 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
)
6501 /* We're doing a "next".
6503 Normal (forward) execution: set a breakpoint at the
6504 callee's return address (the address at which the caller
6507 Reverse (backward) execution. set the step-resume
6508 breakpoint at the start of the function that we just
6509 stepped into (backwards), and continue to there. When we
6510 get there, we'll need to single-step back to the caller. */
6512 if (execution_direction
== EXEC_REVERSE
)
6514 /* If we're already at the start of the function, we've either
6515 just stepped backward into a single instruction function,
6516 or stepped back out of a signal handler to the first instruction
6517 of the function. Just keep going, which will single-step back
6519 if (ecs
->stop_func_start
!= stop_pc
&& ecs
->stop_func_start
!= 0)
6521 /* Normal function call return (static or dynamic). */
6522 symtab_and_line sr_sal
;
6523 sr_sal
.pc
= ecs
->stop_func_start
;
6524 sr_sal
.pspace
= get_frame_program_space (frame
);
6525 insert_step_resume_breakpoint_at_sal (gdbarch
,
6526 sr_sal
, null_frame_id
);
6530 insert_step_resume_breakpoint_at_caller (frame
);
6536 /* If we are in a function call trampoline (a stub between the
6537 calling routine and the real function), locate the real
6538 function. That's what tells us (a) whether we want to step
6539 into it at all, and (b) what prologue we want to run to the
6540 end of, if we do step into it. */
6541 real_stop_pc
= skip_language_trampoline (frame
, stop_pc
);
6542 if (real_stop_pc
== 0)
6543 real_stop_pc
= gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
);
6544 if (real_stop_pc
!= 0)
6545 ecs
->stop_func_start
= real_stop_pc
;
6547 if (real_stop_pc
!= 0 && in_solib_dynsym_resolve_code (real_stop_pc
))
6549 symtab_and_line sr_sal
;
6550 sr_sal
.pc
= ecs
->stop_func_start
;
6551 sr_sal
.pspace
= get_frame_program_space (frame
);
6553 insert_step_resume_breakpoint_at_sal (gdbarch
,
6554 sr_sal
, null_frame_id
);
6559 /* If we have line number information for the function we are
6560 thinking of stepping into and the function isn't on the skip
6563 If there are several symtabs at that PC (e.g. with include
6564 files), just want to know whether *any* of them have line
6565 numbers. find_pc_line handles this. */
6567 struct symtab_and_line tmp_sal
;
6569 tmp_sal
= find_pc_line (ecs
->stop_func_start
, 0);
6570 if (tmp_sal
.line
!= 0
6571 && !function_name_is_marked_for_skip (ecs
->stop_func_name
,
6573 && !inline_frame_is_marked_for_skip (true, ecs
->event_thread
))
6575 if (execution_direction
== EXEC_REVERSE
)
6576 handle_step_into_function_backward (gdbarch
, ecs
);
6578 handle_step_into_function (gdbarch
, ecs
);
6583 /* If we have no line number and the step-stop-if-no-debug is
6584 set, we stop the step so that the user has a chance to switch
6585 in assembly mode. */
6586 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6587 && step_stop_if_no_debug
)
6589 end_stepping_range (ecs
);
6593 if (execution_direction
== EXEC_REVERSE
)
6595 /* If we're already at the start of the function, we've either just
6596 stepped backward into a single instruction function without line
6597 number info, or stepped back out of a signal handler to the first
6598 instruction of the function without line number info. Just keep
6599 going, which will single-step back to the caller. */
6600 if (ecs
->stop_func_start
!= stop_pc
)
6602 /* Set a breakpoint at callee's start address.
6603 From there we can step once and be back in the caller. */
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
);
6612 /* Set a breakpoint at callee's return address (the address
6613 at which the caller will resume). */
6614 insert_step_resume_breakpoint_at_caller (frame
);
6620 /* Reverse stepping through solib trampolines. */
6622 if (execution_direction
== EXEC_REVERSE
6623 && ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_NONE
)
6625 CORE_ADDR stop_pc
= ecs
->event_thread
->suspend
.stop_pc
;
6627 if (gdbarch_skip_trampoline_code (gdbarch
, frame
, stop_pc
)
6628 || (ecs
->stop_func_start
== 0
6629 && in_solib_dynsym_resolve_code (stop_pc
)))
6631 /* Any solib trampoline code can be handled in reverse
6632 by simply continuing to single-step. We have already
6633 executed the solib function (backwards), and a few
6634 steps will take us back through the trampoline to the
6639 else if (in_solib_dynsym_resolve_code (stop_pc
))
6641 /* Stepped backward into the solib dynsym resolver.
6642 Set a breakpoint at its start and continue, then
6643 one more step will take us out. */
6644 symtab_and_line sr_sal
;
6645 sr_sal
.pc
= ecs
->stop_func_start
;
6646 sr_sal
.pspace
= get_frame_program_space (frame
);
6647 insert_step_resume_breakpoint_at_sal (gdbarch
,
6648 sr_sal
, null_frame_id
);
6654 stop_pc_sal
= find_pc_line (ecs
->event_thread
->suspend
.stop_pc
, 0);
6656 /* NOTE: tausq/2004-05-24: This if block used to be done before all
6657 the trampoline processing logic, however, there are some trampolines
6658 that have no names, so we should do trampoline handling first. */
6659 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_UNDEBUGGABLE
6660 && ecs
->stop_func_name
== NULL
6661 && stop_pc_sal
.line
== 0)
6664 fprintf_unfiltered (gdb_stdlog
,
6665 "infrun: stepped into undebuggable function\n");
6667 /* The inferior just stepped into, or returned to, an
6668 undebuggable function (where there is no debugging information
6669 and no line number corresponding to the address where the
6670 inferior stopped). Since we want to skip this kind of code,
6671 we keep going until the inferior returns from this
6672 function - unless the user has asked us not to (via
6673 set step-mode) or we no longer know how to get back
6674 to the call site. */
6675 if (step_stop_if_no_debug
6676 || !frame_id_p (frame_unwind_caller_id (frame
)))
6678 /* If we have no line number and the step-stop-if-no-debug
6679 is set, we stop the step so that the user has a chance to
6680 switch in assembly mode. */
6681 end_stepping_range (ecs
);
6686 /* Set a breakpoint at callee's return address (the address
6687 at which the caller will resume). */
6688 insert_step_resume_breakpoint_at_caller (frame
);
6694 if (ecs
->event_thread
->control
.step_range_end
== 1)
6696 /* It is stepi or nexti. We always want to stop stepping after
6699 fprintf_unfiltered (gdb_stdlog
, "infrun: stepi/nexti\n");
6700 end_stepping_range (ecs
);
6704 if (stop_pc_sal
.line
== 0)
6706 /* We have no line number information. That means to stop
6707 stepping (does this always happen right after one instruction,
6708 when we do "s" in a function with no line numbers,
6709 or can this happen as a result of a return or longjmp?). */
6711 fprintf_unfiltered (gdb_stdlog
, "infrun: no line number info\n");
6712 end_stepping_range (ecs
);
6716 /* Look for "calls" to inlined functions, part one. If the inline
6717 frame machinery detected some skipped call sites, we have entered
6718 a new inline function. */
6720 if (frame_id_eq (get_frame_id (get_current_frame ()),
6721 ecs
->event_thread
->control
.step_frame_id
)
6722 && inline_skipped_frames (ecs
->event_thread
))
6725 fprintf_unfiltered (gdb_stdlog
,
6726 "infrun: stepped into inlined function\n");
6728 symtab_and_line call_sal
= find_frame_sal (get_current_frame ());
6730 if (ecs
->event_thread
->control
.step_over_calls
!= STEP_OVER_ALL
)
6732 /* For "step", we're going to stop. But if the call site
6733 for this inlined function is on the same source line as
6734 we were previously stepping, go down into the function
6735 first. Otherwise stop at the call site. */
6737 if (call_sal
.line
== ecs
->event_thread
->current_line
6738 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6740 step_into_inline_frame (ecs
->event_thread
);
6741 if (inline_frame_is_marked_for_skip (false, ecs
->event_thread
))
6748 end_stepping_range (ecs
);
6753 /* For "next", we should stop at the call site if it is on a
6754 different source line. Otherwise continue through the
6755 inlined function. */
6756 if (call_sal
.line
== ecs
->event_thread
->current_line
6757 && call_sal
.symtab
== ecs
->event_thread
->current_symtab
)
6760 end_stepping_range (ecs
);
6765 /* Look for "calls" to inlined functions, part two. If we are still
6766 in the same real function we were stepping through, but we have
6767 to go further up to find the exact frame ID, we are stepping
6768 through a more inlined call beyond its call site. */
6770 if (get_frame_type (get_current_frame ()) == INLINE_FRAME
6771 && !frame_id_eq (get_frame_id (get_current_frame ()),
6772 ecs
->event_thread
->control
.step_frame_id
)
6773 && stepped_in_from (get_current_frame (),
6774 ecs
->event_thread
->control
.step_frame_id
))
6777 fprintf_unfiltered (gdb_stdlog
,
6778 "infrun: stepping through inlined function\n");
6780 if (ecs
->event_thread
->control
.step_over_calls
== STEP_OVER_ALL
6781 || inline_frame_is_marked_for_skip (false, ecs
->event_thread
))
6784 end_stepping_range (ecs
);
6788 if ((ecs
->event_thread
->suspend
.stop_pc
== stop_pc_sal
.pc
)
6789 && (ecs
->event_thread
->current_line
!= stop_pc_sal
.line
6790 || ecs
->event_thread
->current_symtab
!= stop_pc_sal
.symtab
))
6792 /* We are at the start of a different line. So stop. Note that
6793 we don't stop if we step into the middle of a different line.
6794 That is said to make things like for (;;) statements work
6797 fprintf_unfiltered (gdb_stdlog
,
6798 "infrun: stepped to a different line\n");
6799 end_stepping_range (ecs
);
6803 /* We aren't done stepping.
6805 Optimize by setting the stepping range to the line.
6806 (We might not be in the original line, but if we entered a
6807 new line in mid-statement, we continue stepping. This makes
6808 things like for(;;) statements work better.) */
6810 ecs
->event_thread
->control
.step_range_start
= stop_pc_sal
.pc
;
6811 ecs
->event_thread
->control
.step_range_end
= stop_pc_sal
.end
;
6812 ecs
->event_thread
->control
.may_range_step
= 1;
6813 set_step_info (frame
, stop_pc_sal
);
6816 fprintf_unfiltered (gdb_stdlog
, "infrun: keep going\n");
6820 /* In all-stop mode, if we're currently stepping but have stopped in
6821 some other thread, we may need to switch back to the stepped
6822 thread. Returns true we set the inferior running, false if we left
6823 it stopped (and the event needs further processing). */
6826 switch_back_to_stepped_thread (struct execution_control_state
*ecs
)
6828 if (!target_is_non_stop_p ())
6830 struct thread_info
*stepping_thread
;
6832 /* If any thread is blocked on some internal breakpoint, and we
6833 simply need to step over that breakpoint to get it going
6834 again, do that first. */
6836 /* However, if we see an event for the stepping thread, then we
6837 know all other threads have been moved past their breakpoints
6838 already. Let the caller check whether the step is finished,
6839 etc., before deciding to move it past a breakpoint. */
6840 if (ecs
->event_thread
->control
.step_range_end
!= 0)
6843 /* Check if the current thread is blocked on an incomplete
6844 step-over, interrupted by a random signal. */
6845 if (ecs
->event_thread
->control
.trap_expected
6846 && ecs
->event_thread
->suspend
.stop_signal
!= GDB_SIGNAL_TRAP
)
6850 fprintf_unfiltered (gdb_stdlog
,
6851 "infrun: need to finish step-over of [%s]\n",
6852 target_pid_to_str (ecs
->event_thread
->ptid
).c_str ());
6858 /* Check if the current thread is blocked by a single-step
6859 breakpoint of another thread. */
6860 if (ecs
->hit_singlestep_breakpoint
)
6864 fprintf_unfiltered (gdb_stdlog
,
6865 "infrun: need to step [%s] over single-step "
6867 target_pid_to_str (ecs
->ptid
).c_str ());
6873 /* If this thread needs yet another step-over (e.g., stepping
6874 through a delay slot), do it first before moving on to
6876 if (thread_still_needs_step_over (ecs
->event_thread
))
6880 fprintf_unfiltered (gdb_stdlog
,
6881 "infrun: thread [%s] still needs step-over\n",
6882 target_pid_to_str (ecs
->event_thread
->ptid
).c_str ());
6888 /* If scheduler locking applies even if not stepping, there's no
6889 need to walk over threads. Above we've checked whether the
6890 current thread is stepping. If some other thread not the
6891 event thread is stepping, then it must be that scheduler
6892 locking is not in effect. */
6893 if (schedlock_applies (ecs
->event_thread
))
6896 /* Otherwise, we no longer expect a trap in the current thread.
6897 Clear the trap_expected flag before switching back -- this is
6898 what keep_going does as well, if we call it. */
6899 ecs
->event_thread
->control
.trap_expected
= 0;
6901 /* Likewise, clear the signal if it should not be passed. */
6902 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
6903 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
6905 /* Do all pending step-overs before actually proceeding with
6907 if (start_step_over ())
6909 prepare_to_wait (ecs
);
6913 /* Look for the stepping/nexting thread. */
6914 stepping_thread
= NULL
;
6916 for (thread_info
*tp
: all_non_exited_threads ())
6918 /* Ignore threads of processes the caller is not
6921 && tp
->ptid
.pid () != ecs
->ptid
.pid ())
6924 /* When stepping over a breakpoint, we lock all threads
6925 except the one that needs to move past the breakpoint.
6926 If a non-event thread has this set, the "incomplete
6927 step-over" check above should have caught it earlier. */
6928 if (tp
->control
.trap_expected
)
6930 internal_error (__FILE__
, __LINE__
,
6931 "[%s] has inconsistent state: "
6932 "trap_expected=%d\n",
6933 target_pid_to_str (tp
->ptid
).c_str (),
6934 tp
->control
.trap_expected
);
6937 /* Did we find the stepping thread? */
6938 if (tp
->control
.step_range_end
)
6940 /* Yep. There should only one though. */
6941 gdb_assert (stepping_thread
== NULL
);
6943 /* The event thread is handled at the top, before we
6945 gdb_assert (tp
!= ecs
->event_thread
);
6947 /* If some thread other than the event thread is
6948 stepping, then scheduler locking can't be in effect,
6949 otherwise we wouldn't have resumed the current event
6950 thread in the first place. */
6951 gdb_assert (!schedlock_applies (tp
));
6953 stepping_thread
= tp
;
6957 if (stepping_thread
!= NULL
)
6960 fprintf_unfiltered (gdb_stdlog
,
6961 "infrun: switching back to stepped thread\n");
6963 if (keep_going_stepped_thread (stepping_thread
))
6965 prepare_to_wait (ecs
);
6974 /* Set a previously stepped thread back to stepping. Returns true on
6975 success, false if the resume is not possible (e.g., the thread
6979 keep_going_stepped_thread (struct thread_info
*tp
)
6981 struct frame_info
*frame
;
6982 struct execution_control_state ecss
;
6983 struct execution_control_state
*ecs
= &ecss
;
6985 /* If the stepping thread exited, then don't try to switch back and
6986 resume it, which could fail in several different ways depending
6987 on the target. Instead, just keep going.
6989 We can find a stepping dead thread in the thread list in two
6992 - The target supports thread exit events, and when the target
6993 tries to delete the thread from the thread list, inferior_ptid
6994 pointed at the exiting thread. In such case, calling
6995 delete_thread does not really remove the thread from the list;
6996 instead, the thread is left listed, with 'exited' state.
6998 - The target's debug interface does not support thread exit
6999 events, and so we have no idea whatsoever if the previously
7000 stepping thread is still alive. For that reason, we need to
7001 synchronously query the target now. */
7003 if (tp
->state
== THREAD_EXITED
|| !target_thread_alive (tp
->ptid
))
7006 fprintf_unfiltered (gdb_stdlog
,
7007 "infrun: not resuming previously "
7008 "stepped thread, it has vanished\n");
7015 fprintf_unfiltered (gdb_stdlog
,
7016 "infrun: resuming previously stepped thread\n");
7018 reset_ecs (ecs
, tp
);
7019 switch_to_thread (tp
);
7021 tp
->suspend
.stop_pc
= regcache_read_pc (get_thread_regcache (tp
));
7022 frame
= get_current_frame ();
7024 /* If the PC of the thread we were trying to single-step has
7025 changed, then that thread has trapped or been signaled, but the
7026 event has not been reported to GDB yet. Re-poll the target
7027 looking for this particular thread's event (i.e. temporarily
7028 enable schedlock) by:
7030 - setting a break at the current PC
7031 - resuming that particular thread, only (by setting trap
7034 This prevents us continuously moving the single-step breakpoint
7035 forward, one instruction at a time, overstepping. */
7037 if (tp
->suspend
.stop_pc
!= tp
->prev_pc
)
7042 fprintf_unfiltered (gdb_stdlog
,
7043 "infrun: expected thread advanced also (%s -> %s)\n",
7044 paddress (target_gdbarch (), tp
->prev_pc
),
7045 paddress (target_gdbarch (), tp
->suspend
.stop_pc
));
7047 /* Clear the info of the previous step-over, as it's no longer
7048 valid (if the thread was trying to step over a breakpoint, it
7049 has already succeeded). It's what keep_going would do too,
7050 if we called it. Do this before trying to insert the sss
7051 breakpoint, otherwise if we were previously trying to step
7052 over this exact address in another thread, the breakpoint is
7054 clear_step_over_info ();
7055 tp
->control
.trap_expected
= 0;
7057 insert_single_step_breakpoint (get_frame_arch (frame
),
7058 get_frame_address_space (frame
),
7059 tp
->suspend
.stop_pc
);
7062 resume_ptid
= internal_resume_ptid (tp
->control
.stepping_command
);
7063 do_target_resume (resume_ptid
, 0, GDB_SIGNAL_0
);
7068 fprintf_unfiltered (gdb_stdlog
,
7069 "infrun: expected thread still hasn't advanced\n");
7071 keep_going_pass_signal (ecs
);
7076 /* Is thread TP in the middle of (software or hardware)
7077 single-stepping? (Note the result of this function must never be
7078 passed directly as target_resume's STEP parameter.) */
7081 currently_stepping (struct thread_info
*tp
)
7083 return ((tp
->control
.step_range_end
7084 && tp
->control
.step_resume_breakpoint
== NULL
)
7085 || tp
->control
.trap_expected
7086 || tp
->stepped_breakpoint
7087 || bpstat_should_step ());
7090 /* Inferior has stepped into a subroutine call with source code that
7091 we should not step over. Do step to the first line of code in
7095 handle_step_into_function (struct gdbarch
*gdbarch
,
7096 struct execution_control_state
*ecs
)
7098 fill_in_stop_func (gdbarch
, ecs
);
7100 compunit_symtab
*cust
7101 = find_pc_compunit_symtab (ecs
->event_thread
->suspend
.stop_pc
);
7102 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7103 ecs
->stop_func_start
7104 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7106 symtab_and_line stop_func_sal
= find_pc_line (ecs
->stop_func_start
, 0);
7107 /* Use the step_resume_break to step until the end of the prologue,
7108 even if that involves jumps (as it seems to on the vax under
7110 /* If the prologue ends in the middle of a source line, continue to
7111 the end of that source line (if it is still within the function).
7112 Otherwise, just go to end of prologue. */
7113 if (stop_func_sal
.end
7114 && stop_func_sal
.pc
!= ecs
->stop_func_start
7115 && stop_func_sal
.end
< ecs
->stop_func_end
)
7116 ecs
->stop_func_start
= stop_func_sal
.end
;
7118 /* Architectures which require breakpoint adjustment might not be able
7119 to place a breakpoint at the computed address. If so, the test
7120 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
7121 ecs->stop_func_start to an address at which a breakpoint may be
7122 legitimately placed.
7124 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
7125 made, GDB will enter an infinite loop when stepping through
7126 optimized code consisting of VLIW instructions which contain
7127 subinstructions corresponding to different source lines. On
7128 FR-V, it's not permitted to place a breakpoint on any but the
7129 first subinstruction of a VLIW instruction. When a breakpoint is
7130 set, GDB will adjust the breakpoint address to the beginning of
7131 the VLIW instruction. Thus, we need to make the corresponding
7132 adjustment here when computing the stop address. */
7134 if (gdbarch_adjust_breakpoint_address_p (gdbarch
))
7136 ecs
->stop_func_start
7137 = gdbarch_adjust_breakpoint_address (gdbarch
,
7138 ecs
->stop_func_start
);
7141 if (ecs
->stop_func_start
== ecs
->event_thread
->suspend
.stop_pc
)
7143 /* We are already there: stop now. */
7144 end_stepping_range (ecs
);
7149 /* Put the step-breakpoint there and go until there. */
7150 symtab_and_line sr_sal
;
7151 sr_sal
.pc
= ecs
->stop_func_start
;
7152 sr_sal
.section
= find_pc_overlay (ecs
->stop_func_start
);
7153 sr_sal
.pspace
= get_frame_program_space (get_current_frame ());
7155 /* Do not specify what the fp should be when we stop since on
7156 some machines the prologue is where the new fp value is
7158 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
, null_frame_id
);
7160 /* And make sure stepping stops right away then. */
7161 ecs
->event_thread
->control
.step_range_end
7162 = ecs
->event_thread
->control
.step_range_start
;
7167 /* Inferior has stepped backward into a subroutine call with source
7168 code that we should not step over. Do step to the beginning of the
7169 last line of code in it. */
7172 handle_step_into_function_backward (struct gdbarch
*gdbarch
,
7173 struct execution_control_state
*ecs
)
7175 struct compunit_symtab
*cust
;
7176 struct symtab_and_line stop_func_sal
;
7178 fill_in_stop_func (gdbarch
, ecs
);
7180 cust
= find_pc_compunit_symtab (ecs
->event_thread
->suspend
.stop_pc
);
7181 if (cust
!= NULL
&& compunit_language (cust
) != language_asm
)
7182 ecs
->stop_func_start
7183 = gdbarch_skip_prologue_noexcept (gdbarch
, ecs
->stop_func_start
);
7185 stop_func_sal
= find_pc_line (ecs
->event_thread
->suspend
.stop_pc
, 0);
7187 /* OK, we're just going to keep stepping here. */
7188 if (stop_func_sal
.pc
== ecs
->event_thread
->suspend
.stop_pc
)
7190 /* We're there already. Just stop stepping now. */
7191 end_stepping_range (ecs
);
7195 /* Else just reset the step range and keep going.
7196 No step-resume breakpoint, they don't work for
7197 epilogues, which can have multiple entry paths. */
7198 ecs
->event_thread
->control
.step_range_start
= stop_func_sal
.pc
;
7199 ecs
->event_thread
->control
.step_range_end
= stop_func_sal
.end
;
7205 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
7206 This is used to both functions and to skip over code. */
7209 insert_step_resume_breakpoint_at_sal_1 (struct gdbarch
*gdbarch
,
7210 struct symtab_and_line sr_sal
,
7211 struct frame_id sr_id
,
7212 enum bptype sr_type
)
7214 /* There should never be more than one step-resume or longjmp-resume
7215 breakpoint per thread, so we should never be setting a new
7216 step_resume_breakpoint when one is already active. */
7217 gdb_assert (inferior_thread ()->control
.step_resume_breakpoint
== NULL
);
7218 gdb_assert (sr_type
== bp_step_resume
|| sr_type
== bp_hp_step_resume
);
7221 fprintf_unfiltered (gdb_stdlog
,
7222 "infrun: inserting step-resume breakpoint at %s\n",
7223 paddress (gdbarch
, sr_sal
.pc
));
7225 inferior_thread ()->control
.step_resume_breakpoint
7226 = set_momentary_breakpoint (gdbarch
, sr_sal
, sr_id
, sr_type
).release ();
7230 insert_step_resume_breakpoint_at_sal (struct gdbarch
*gdbarch
,
7231 struct symtab_and_line sr_sal
,
7232 struct frame_id sr_id
)
7234 insert_step_resume_breakpoint_at_sal_1 (gdbarch
,
7239 /* Insert a "high-priority step-resume breakpoint" at RETURN_FRAME.pc.
7240 This is used to skip a potential signal handler.
7242 This is called with the interrupted function's frame. The signal
7243 handler, when it returns, will resume the interrupted function at
7247 insert_hp_step_resume_breakpoint_at_frame (struct frame_info
*return_frame
)
7249 gdb_assert (return_frame
!= NULL
);
7251 struct gdbarch
*gdbarch
= get_frame_arch (return_frame
);
7253 symtab_and_line sr_sal
;
7254 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
, get_frame_pc (return_frame
));
7255 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7256 sr_sal
.pspace
= get_frame_program_space (return_frame
);
7258 insert_step_resume_breakpoint_at_sal_1 (gdbarch
, sr_sal
,
7259 get_stack_frame_id (return_frame
),
7263 /* Insert a "step-resume breakpoint" at the previous frame's PC. This
7264 is used to skip a function after stepping into it (for "next" or if
7265 the called function has no debugging information).
7267 The current function has almost always been reached by single
7268 stepping a call or return instruction. NEXT_FRAME belongs to the
7269 current function, and the breakpoint will be set at the caller's
7272 This is a separate function rather than reusing
7273 insert_hp_step_resume_breakpoint_at_frame in order to avoid
7274 get_prev_frame, which may stop prematurely (see the implementation
7275 of frame_unwind_caller_id for an example). */
7278 insert_step_resume_breakpoint_at_caller (struct frame_info
*next_frame
)
7280 /* We shouldn't have gotten here if we don't know where the call site
7282 gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame
)));
7284 struct gdbarch
*gdbarch
= frame_unwind_caller_arch (next_frame
);
7286 symtab_and_line sr_sal
;
7287 sr_sal
.pc
= gdbarch_addr_bits_remove (gdbarch
,
7288 frame_unwind_caller_pc (next_frame
));
7289 sr_sal
.section
= find_pc_overlay (sr_sal
.pc
);
7290 sr_sal
.pspace
= frame_unwind_program_space (next_frame
);
7292 insert_step_resume_breakpoint_at_sal (gdbarch
, sr_sal
,
7293 frame_unwind_caller_id (next_frame
));
7296 /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
7297 new breakpoint at the target of a jmp_buf. The handling of
7298 longjmp-resume uses the same mechanisms used for handling
7299 "step-resume" breakpoints. */
7302 insert_longjmp_resume_breakpoint (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
7304 /* There should never be more than one longjmp-resume breakpoint per
7305 thread, so we should never be setting a new
7306 longjmp_resume_breakpoint when one is already active. */
7307 gdb_assert (inferior_thread ()->control
.exception_resume_breakpoint
== NULL
);
7310 fprintf_unfiltered (gdb_stdlog
,
7311 "infrun: inserting longjmp-resume breakpoint at %s\n",
7312 paddress (gdbarch
, pc
));
7314 inferior_thread ()->control
.exception_resume_breakpoint
=
7315 set_momentary_breakpoint_at_pc (gdbarch
, pc
, bp_longjmp_resume
).release ();
7318 /* Insert an exception resume breakpoint. TP is the thread throwing
7319 the exception. The block B is the block of the unwinder debug hook
7320 function. FRAME is the frame corresponding to the call to this
7321 function. SYM is the symbol of the function argument holding the
7322 target PC of the exception. */
7325 insert_exception_resume_breakpoint (struct thread_info
*tp
,
7326 const struct block
*b
,
7327 struct frame_info
*frame
,
7332 struct block_symbol vsym
;
7333 struct value
*value
;
7335 struct breakpoint
*bp
;
7337 vsym
= lookup_symbol_search_name (sym
->search_name (),
7339 value
= read_var_value (vsym
.symbol
, vsym
.block
, frame
);
7340 /* If the value was optimized out, revert to the old behavior. */
7341 if (! value_optimized_out (value
))
7343 handler
= value_as_address (value
);
7346 fprintf_unfiltered (gdb_stdlog
,
7347 "infrun: exception resume at %lx\n",
7348 (unsigned long) handler
);
7350 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7352 bp_exception_resume
).release ();
7354 /* set_momentary_breakpoint_at_pc invalidates FRAME. */
7357 bp
->thread
= tp
->global_num
;
7358 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7361 catch (const gdb_exception_error
&e
)
7363 /* We want to ignore errors here. */
7367 /* A helper for check_exception_resume that sets an
7368 exception-breakpoint based on a SystemTap probe. */
7371 insert_exception_resume_from_probe (struct thread_info
*tp
,
7372 const struct bound_probe
*probe
,
7373 struct frame_info
*frame
)
7375 struct value
*arg_value
;
7377 struct breakpoint
*bp
;
7379 arg_value
= probe_safe_evaluate_at_pc (frame
, 1);
7383 handler
= value_as_address (arg_value
);
7386 fprintf_unfiltered (gdb_stdlog
,
7387 "infrun: exception resume at %s\n",
7388 paddress (get_objfile_arch (probe
->objfile
),
7391 bp
= set_momentary_breakpoint_at_pc (get_frame_arch (frame
),
7392 handler
, bp_exception_resume
).release ();
7393 bp
->thread
= tp
->global_num
;
7394 inferior_thread ()->control
.exception_resume_breakpoint
= bp
;
7397 /* This is called when an exception has been intercepted. Check to
7398 see whether the exception's destination is of interest, and if so,
7399 set an exception resume breakpoint there. */
7402 check_exception_resume (struct execution_control_state
*ecs
,
7403 struct frame_info
*frame
)
7405 struct bound_probe probe
;
7406 struct symbol
*func
;
7408 /* First see if this exception unwinding breakpoint was set via a
7409 SystemTap probe point. If so, the probe has two arguments: the
7410 CFA and the HANDLER. We ignore the CFA, extract the handler, and
7411 set a breakpoint there. */
7412 probe
= find_probe_by_pc (get_frame_pc (frame
));
7415 insert_exception_resume_from_probe (ecs
->event_thread
, &probe
, frame
);
7419 func
= get_frame_function (frame
);
7425 const struct block
*b
;
7426 struct block_iterator iter
;
7430 /* The exception breakpoint is a thread-specific breakpoint on
7431 the unwinder's debug hook, declared as:
7433 void _Unwind_DebugHook (void *cfa, void *handler);
7435 The CFA argument indicates the frame to which control is
7436 about to be transferred. HANDLER is the destination PC.
7438 We ignore the CFA and set a temporary breakpoint at HANDLER.
7439 This is not extremely efficient but it avoids issues in gdb
7440 with computing the DWARF CFA, and it also works even in weird
7441 cases such as throwing an exception from inside a signal
7444 b
= SYMBOL_BLOCK_VALUE (func
);
7445 ALL_BLOCK_SYMBOLS (b
, iter
, sym
)
7447 if (!SYMBOL_IS_ARGUMENT (sym
))
7454 insert_exception_resume_breakpoint (ecs
->event_thread
,
7460 catch (const gdb_exception_error
&e
)
7466 stop_waiting (struct execution_control_state
*ecs
)
7469 fprintf_unfiltered (gdb_stdlog
, "infrun: stop_waiting\n");
7471 /* Let callers know we don't want to wait for the inferior anymore. */
7472 ecs
->wait_some_more
= 0;
7474 /* If all-stop, but the target is always in non-stop mode, stop all
7475 threads now that we're presenting the stop to the user. */
7476 if (!non_stop
&& target_is_non_stop_p ())
7477 stop_all_threads ();
7480 /* Like keep_going, but passes the signal to the inferior, even if the
7481 signal is set to nopass. */
7484 keep_going_pass_signal (struct execution_control_state
*ecs
)
7486 gdb_assert (ecs
->event_thread
->ptid
== inferior_ptid
);
7487 gdb_assert (!ecs
->event_thread
->resumed
);
7489 /* Save the pc before execution, to compare with pc after stop. */
7490 ecs
->event_thread
->prev_pc
7491 = regcache_read_pc (get_thread_regcache (ecs
->event_thread
));
7493 if (ecs
->event_thread
->control
.trap_expected
)
7495 struct thread_info
*tp
= ecs
->event_thread
;
7498 fprintf_unfiltered (gdb_stdlog
,
7499 "infrun: %s has trap_expected set, "
7500 "resuming to collect trap\n",
7501 target_pid_to_str (tp
->ptid
).c_str ());
7503 /* We haven't yet gotten our trap, and either: intercepted a
7504 non-signal event (e.g., a fork); or took a signal which we
7505 are supposed to pass through to the inferior. Simply
7507 resume (ecs
->event_thread
->suspend
.stop_signal
);
7509 else if (step_over_info_valid_p ())
7511 /* Another thread is stepping over a breakpoint in-line. If
7512 this thread needs a step-over too, queue the request. In
7513 either case, this resume must be deferred for later. */
7514 struct thread_info
*tp
= ecs
->event_thread
;
7516 if (ecs
->hit_singlestep_breakpoint
7517 || thread_still_needs_step_over (tp
))
7520 fprintf_unfiltered (gdb_stdlog
,
7521 "infrun: step-over already in progress: "
7522 "step-over for %s deferred\n",
7523 target_pid_to_str (tp
->ptid
).c_str ());
7524 thread_step_over_chain_enqueue (tp
);
7529 fprintf_unfiltered (gdb_stdlog
,
7530 "infrun: step-over in progress: "
7531 "resume of %s deferred\n",
7532 target_pid_to_str (tp
->ptid
).c_str ());
7537 struct regcache
*regcache
= get_current_regcache ();
7540 step_over_what step_what
;
7542 /* Either the trap was not expected, but we are continuing
7543 anyway (if we got a signal, the user asked it be passed to
7546 We got our expected trap, but decided we should resume from
7549 We're going to run this baby now!
7551 Note that insert_breakpoints won't try to re-insert
7552 already inserted breakpoints. Therefore, we don't
7553 care if breakpoints were already inserted, or not. */
7555 /* If we need to step over a breakpoint, and we're not using
7556 displaced stepping to do so, insert all breakpoints
7557 (watchpoints, etc.) but the one we're stepping over, step one
7558 instruction, and then re-insert the breakpoint when that step
7561 step_what
= thread_still_needs_step_over (ecs
->event_thread
);
7563 remove_bp
= (ecs
->hit_singlestep_breakpoint
7564 || (step_what
& STEP_OVER_BREAKPOINT
));
7565 remove_wps
= (step_what
& STEP_OVER_WATCHPOINT
);
7567 /* We can't use displaced stepping if we need to step past a
7568 watchpoint. The instruction copied to the scratch pad would
7569 still trigger the watchpoint. */
7571 && (remove_wps
|| !use_displaced_stepping (ecs
->event_thread
)))
7573 set_step_over_info (regcache
->aspace (),
7574 regcache_read_pc (regcache
), remove_wps
,
7575 ecs
->event_thread
->global_num
);
7577 else if (remove_wps
)
7578 set_step_over_info (NULL
, 0, remove_wps
, -1);
7580 /* If we now need to do an in-line step-over, we need to stop
7581 all other threads. Note this must be done before
7582 insert_breakpoints below, because that removes the breakpoint
7583 we're about to step over, otherwise other threads could miss
7585 if (step_over_info_valid_p () && target_is_non_stop_p ())
7586 stop_all_threads ();
7588 /* Stop stepping if inserting breakpoints fails. */
7591 insert_breakpoints ();
7593 catch (const gdb_exception_error
&e
)
7595 exception_print (gdb_stderr
, e
);
7597 clear_step_over_info ();
7601 ecs
->event_thread
->control
.trap_expected
= (remove_bp
|| remove_wps
);
7603 resume (ecs
->event_thread
->suspend
.stop_signal
);
7606 prepare_to_wait (ecs
);
7609 /* Called when we should continue running the inferior, because the
7610 current event doesn't cause a user visible stop. This does the
7611 resuming part; waiting for the next event is done elsewhere. */
7614 keep_going (struct execution_control_state
*ecs
)
7616 if (ecs
->event_thread
->control
.trap_expected
7617 && ecs
->event_thread
->suspend
.stop_signal
== GDB_SIGNAL_TRAP
)
7618 ecs
->event_thread
->control
.trap_expected
= 0;
7620 if (!signal_program
[ecs
->event_thread
->suspend
.stop_signal
])
7621 ecs
->event_thread
->suspend
.stop_signal
= GDB_SIGNAL_0
;
7622 keep_going_pass_signal (ecs
);
7625 /* This function normally comes after a resume, before
7626 handle_inferior_event exits. It takes care of any last bits of
7627 housekeeping, and sets the all-important wait_some_more flag. */
7630 prepare_to_wait (struct execution_control_state
*ecs
)
7633 fprintf_unfiltered (gdb_stdlog
, "infrun: prepare_to_wait\n");
7635 ecs
->wait_some_more
= 1;
7637 if (!target_is_async_p ())
7638 mark_infrun_async_event_handler ();
7641 /* We are done with the step range of a step/next/si/ni command.
7642 Called once for each n of a "step n" operation. */
7645 end_stepping_range (struct execution_control_state
*ecs
)
7647 ecs
->event_thread
->control
.stop_step
= 1;
7651 /* Several print_*_reason functions to print why the inferior has stopped.
7652 We always print something when the inferior exits, or receives a signal.
7653 The rest of the cases are dealt with later on in normal_stop and
7654 print_it_typical. Ideally there should be a call to one of these
7655 print_*_reason functions functions from handle_inferior_event each time
7656 stop_waiting is called.
7658 Note that we don't call these directly, instead we delegate that to
7659 the interpreters, through observers. Interpreters then call these
7660 with whatever uiout is right. */
7663 print_end_stepping_range_reason (struct ui_out
*uiout
)
7665 /* For CLI-like interpreters, print nothing. */
7667 if (uiout
->is_mi_like_p ())
7669 uiout
->field_string ("reason",
7670 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE
));
7675 print_signal_exited_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7677 annotate_signalled ();
7678 if (uiout
->is_mi_like_p ())
7680 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED
));
7681 uiout
->text ("\nProgram terminated with signal ");
7682 annotate_signal_name ();
7683 uiout
->field_string ("signal-name",
7684 gdb_signal_to_name (siggnal
));
7685 annotate_signal_name_end ();
7687 annotate_signal_string ();
7688 uiout
->field_string ("signal-meaning",
7689 gdb_signal_to_string (siggnal
));
7690 annotate_signal_string_end ();
7691 uiout
->text (".\n");
7692 uiout
->text ("The program no longer exists.\n");
7696 print_exited_reason (struct ui_out
*uiout
, int exitstatus
)
7698 struct inferior
*inf
= current_inferior ();
7699 std::string pidstr
= target_pid_to_str (ptid_t (inf
->pid
));
7701 annotate_exited (exitstatus
);
7704 if (uiout
->is_mi_like_p ())
7705 uiout
->field_string ("reason", async_reason_lookup (EXEC_ASYNC_EXITED
));
7706 std::string exit_code_str
7707 = string_printf ("0%o", (unsigned int) exitstatus
);
7708 uiout
->message ("[Inferior %s (%s) exited with code %pF]\n",
7709 plongest (inf
->num
), pidstr
.c_str (),
7710 string_field ("exit-code", exit_code_str
.c_str ()));
7714 if (uiout
->is_mi_like_p ())
7716 ("reason", async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY
));
7717 uiout
->message ("[Inferior %s (%s) exited normally]\n",
7718 plongest (inf
->num
), pidstr
.c_str ());
7722 /* Some targets/architectures can do extra processing/display of
7723 segmentation faults. E.g., Intel MPX boundary faults.
7724 Call the architecture dependent function to handle the fault. */
7727 handle_segmentation_fault (struct ui_out
*uiout
)
7729 struct regcache
*regcache
= get_current_regcache ();
7730 struct gdbarch
*gdbarch
= regcache
->arch ();
7732 if (gdbarch_handle_segmentation_fault_p (gdbarch
))
7733 gdbarch_handle_segmentation_fault (gdbarch
, uiout
);
7737 print_signal_received_reason (struct ui_out
*uiout
, enum gdb_signal siggnal
)
7739 struct thread_info
*thr
= inferior_thread ();
7743 if (uiout
->is_mi_like_p ())
7745 else if (show_thread_that_caused_stop ())
7749 uiout
->text ("\nThread ");
7750 uiout
->field_string ("thread-id", print_thread_id (thr
));
7752 name
= thr
->name
!= NULL
? thr
->name
: target_thread_name (thr
);
7755 uiout
->text (" \"");
7756 uiout
->field_string ("name", name
);
7761 uiout
->text ("\nProgram");
7763 if (siggnal
== GDB_SIGNAL_0
&& !uiout
->is_mi_like_p ())
7764 uiout
->text (" stopped");
7767 uiout
->text (" received signal ");
7768 annotate_signal_name ();
7769 if (uiout
->is_mi_like_p ())
7771 ("reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED
));
7772 uiout
->field_string ("signal-name", gdb_signal_to_name (siggnal
));
7773 annotate_signal_name_end ();
7775 annotate_signal_string ();
7776 uiout
->field_string ("signal-meaning", gdb_signal_to_string (siggnal
));
7778 if (siggnal
== GDB_SIGNAL_SEGV
)
7779 handle_segmentation_fault (uiout
);
7781 annotate_signal_string_end ();
7783 uiout
->text (".\n");
7787 print_no_history_reason (struct ui_out
*uiout
)
7789 uiout
->text ("\nNo more reverse-execution history.\n");
7792 /* Print current location without a level number, if we have changed
7793 functions or hit a breakpoint. Print source line if we have one.
7794 bpstat_print contains the logic deciding in detail what to print,
7795 based on the event(s) that just occurred. */
7798 print_stop_location (struct target_waitstatus
*ws
)
7801 enum print_what source_flag
;
7802 int do_frame_printing
= 1;
7803 struct thread_info
*tp
= inferior_thread ();
7805 bpstat_ret
= bpstat_print (tp
->control
.stop_bpstat
, ws
->kind
);
7809 /* FIXME: cagney/2002-12-01: Given that a frame ID does (or
7810 should) carry around the function and does (or should) use
7811 that when doing a frame comparison. */
7812 if (tp
->control
.stop_step
7813 && frame_id_eq (tp
->control
.step_frame_id
,
7814 get_frame_id (get_current_frame ()))
7815 && (tp
->control
.step_start_function
7816 == find_pc_function (tp
->suspend
.stop_pc
)))
7818 /* Finished step, just print source line. */
7819 source_flag
= SRC_LINE
;
7823 /* Print location and source line. */
7824 source_flag
= SRC_AND_LOC
;
7827 case PRINT_SRC_AND_LOC
:
7828 /* Print location and source line. */
7829 source_flag
= SRC_AND_LOC
;
7831 case PRINT_SRC_ONLY
:
7832 source_flag
= SRC_LINE
;
7835 /* Something bogus. */
7836 source_flag
= SRC_LINE
;
7837 do_frame_printing
= 0;
7840 internal_error (__FILE__
, __LINE__
, _("Unknown value."));
7843 /* The behavior of this routine with respect to the source
7845 SRC_LINE: Print only source line
7846 LOCATION: Print only location
7847 SRC_AND_LOC: Print location and source line. */
7848 if (do_frame_printing
)
7849 print_stack_frame (get_selected_frame (NULL
), 0, source_flag
, 1);
7855 print_stop_event (struct ui_out
*uiout
, bool displays
)
7857 struct target_waitstatus last
;
7859 struct thread_info
*tp
;
7861 get_last_target_status (&last_ptid
, &last
);
7864 scoped_restore save_uiout
= make_scoped_restore (¤t_uiout
, uiout
);
7866 print_stop_location (&last
);
7868 /* Display the auto-display expressions. */
7873 tp
= inferior_thread ();
7874 if (tp
->thread_fsm
!= NULL
7875 && tp
->thread_fsm
->finished_p ())
7877 struct return_value_info
*rv
;
7879 rv
= tp
->thread_fsm
->return_value ();
7881 print_return_value (uiout
, rv
);
7888 maybe_remove_breakpoints (void)
7890 if (!breakpoints_should_be_inserted_now () && target_has_execution
)
7892 if (remove_breakpoints ())
7894 target_terminal::ours_for_output ();
7895 printf_filtered (_("Cannot remove breakpoints because "
7896 "program is no longer writable.\nFurther "
7897 "execution is probably impossible.\n"));
7902 /* The execution context that just caused a normal stop. */
7909 DISABLE_COPY_AND_ASSIGN (stop_context
);
7911 bool changed () const;
7916 /* The event PTID. */
7920 /* If stopp for a thread event, this is the thread that caused the
7922 struct thread_info
*thread
;
7924 /* The inferior that caused the stop. */
7928 /* Initializes a new stop context. If stopped for a thread event, this
7929 takes a strong reference to the thread. */
7931 stop_context::stop_context ()
7933 stop_id
= get_stop_id ();
7934 ptid
= inferior_ptid
;
7935 inf_num
= current_inferior ()->num
;
7937 if (inferior_ptid
!= null_ptid
)
7939 /* Take a strong reference so that the thread can't be deleted
7941 thread
= inferior_thread ();
7948 /* Release a stop context previously created with save_stop_context.
7949 Releases the strong reference to the thread as well. */
7951 stop_context::~stop_context ()
7957 /* Return true if the current context no longer matches the saved stop
7961 stop_context::changed () const
7963 if (ptid
!= inferior_ptid
)
7965 if (inf_num
!= current_inferior ()->num
)
7967 if (thread
!= NULL
&& thread
->state
!= THREAD_STOPPED
)
7969 if (get_stop_id () != stop_id
)
7979 struct target_waitstatus last
;
7982 get_last_target_status (&last_ptid
, &last
);
7986 /* If an exception is thrown from this point on, make sure to
7987 propagate GDB's knowledge of the executing state to the
7988 frontend/user running state. A QUIT is an easy exception to see
7989 here, so do this before any filtered output. */
7991 gdb::optional
<scoped_finish_thread_state
> maybe_finish_thread_state
;
7994 maybe_finish_thread_state
.emplace (minus_one_ptid
);
7995 else if (last
.kind
== TARGET_WAITKIND_SIGNALLED
7996 || last
.kind
== TARGET_WAITKIND_EXITED
)
7998 /* On some targets, we may still have live threads in the
7999 inferior when we get a process exit event. E.g., for
8000 "checkpoint", when the current checkpoint/fork exits,
8001 linux-fork.c automatically switches to another fork from
8002 within target_mourn_inferior. */
8003 if (inferior_ptid
!= null_ptid
)
8004 maybe_finish_thread_state
.emplace (ptid_t (inferior_ptid
.pid ()));
8006 else if (last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8007 maybe_finish_thread_state
.emplace (inferior_ptid
);
8009 /* As we're presenting a stop, and potentially removing breakpoints,
8010 update the thread list so we can tell whether there are threads
8011 running on the target. With target remote, for example, we can
8012 only learn about new threads when we explicitly update the thread
8013 list. Do this before notifying the interpreters about signal
8014 stops, end of stepping ranges, etc., so that the "new thread"
8015 output is emitted before e.g., "Program received signal FOO",
8016 instead of after. */
8017 update_thread_list ();
8019 if (last
.kind
== TARGET_WAITKIND_STOPPED
&& stopped_by_random_signal
)
8020 gdb::observers::signal_received
.notify (inferior_thread ()->suspend
.stop_signal
);
8022 /* As with the notification of thread events, we want to delay
8023 notifying the user that we've switched thread context until
8024 the inferior actually stops.
8026 There's no point in saying anything if the inferior has exited.
8027 Note that SIGNALLED here means "exited with a signal", not
8028 "received a signal".
8030 Also skip saying anything in non-stop mode. In that mode, as we
8031 don't want GDB to switch threads behind the user's back, to avoid
8032 races where the user is typing a command to apply to thread x,
8033 but GDB switches to thread y before the user finishes entering
8034 the command, fetch_inferior_event installs a cleanup to restore
8035 the current thread back to the thread the user had selected right
8036 after this event is handled, so we're not really switching, only
8037 informing of a stop. */
8039 && previous_inferior_ptid
!= inferior_ptid
8040 && target_has_execution
8041 && last
.kind
!= TARGET_WAITKIND_SIGNALLED
8042 && last
.kind
!= TARGET_WAITKIND_EXITED
8043 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8045 SWITCH_THRU_ALL_UIS ()
8047 target_terminal::ours_for_output ();
8048 printf_filtered (_("[Switching to %s]\n"),
8049 target_pid_to_str (inferior_ptid
).c_str ());
8050 annotate_thread_changed ();
8052 previous_inferior_ptid
= inferior_ptid
;
8055 if (last
.kind
== TARGET_WAITKIND_NO_RESUMED
)
8057 SWITCH_THRU_ALL_UIS ()
8058 if (current_ui
->prompt_state
== PROMPT_BLOCKED
)
8060 target_terminal::ours_for_output ();
8061 printf_filtered (_("No unwaited-for children left.\n"));
8065 /* Note: this depends on the update_thread_list call above. */
8066 maybe_remove_breakpoints ();
8068 /* If an auto-display called a function and that got a signal,
8069 delete that auto-display to avoid an infinite recursion. */
8071 if (stopped_by_random_signal
)
8072 disable_current_display ();
8074 SWITCH_THRU_ALL_UIS ()
8076 async_enable_stdin ();
8079 /* Let the user/frontend see the threads as stopped. */
8080 maybe_finish_thread_state
.reset ();
8082 /* Select innermost stack frame - i.e., current frame is frame 0,
8083 and current location is based on that. Handle the case where the
8084 dummy call is returning after being stopped. E.g. the dummy call
8085 previously hit a breakpoint. (If the dummy call returns
8086 normally, we won't reach here.) Do this before the stop hook is
8087 run, so that it doesn't get to see the temporary dummy frame,
8088 which is not where we'll present the stop. */
8089 if (has_stack_frames ())
8091 if (stop_stack_dummy
== STOP_STACK_DUMMY
)
8093 /* Pop the empty frame that contains the stack dummy. This
8094 also restores inferior state prior to the call (struct
8095 infcall_suspend_state). */
8096 struct frame_info
*frame
= get_current_frame ();
8098 gdb_assert (get_frame_type (frame
) == DUMMY_FRAME
);
8100 /* frame_pop calls reinit_frame_cache as the last thing it
8101 does which means there's now no selected frame. */
8104 select_frame (get_current_frame ());
8106 /* Set the current source location. */
8107 set_current_sal_from_frame (get_current_frame ());
8110 /* Look up the hook_stop and run it (CLI internally handles problem
8111 of stop_command's pre-hook not existing). */
8112 if (stop_command
!= NULL
)
8114 stop_context saved_context
;
8118 execute_cmd_pre_hook (stop_command
);
8120 catch (const gdb_exception
&ex
)
8122 exception_fprintf (gdb_stderr
, ex
,
8123 "Error while running hook_stop:\n");
8126 /* If the stop hook resumes the target, then there's no point in
8127 trying to notify about the previous stop; its context is
8128 gone. Likewise if the command switches thread or inferior --
8129 the observers would print a stop for the wrong
8131 if (saved_context
.changed ())
8135 /* Notify observers about the stop. This is where the interpreters
8136 print the stop event. */
8137 if (inferior_ptid
!= null_ptid
)
8138 gdb::observers::normal_stop
.notify (inferior_thread ()->control
.stop_bpstat
,
8141 gdb::observers::normal_stop
.notify (NULL
, stop_print_frame
);
8143 annotate_stopped ();
8145 if (target_has_execution
)
8147 if (last
.kind
!= TARGET_WAITKIND_SIGNALLED
8148 && last
.kind
!= TARGET_WAITKIND_EXITED
8149 && last
.kind
!= TARGET_WAITKIND_NO_RESUMED
)
8150 /* Delete the breakpoint we stopped at, if it wants to be deleted.
8151 Delete any breakpoint that is to be deleted at the next stop. */
8152 breakpoint_auto_delete (inferior_thread ()->control
.stop_bpstat
);
8155 /* Try to get rid of automatically added inferiors that are no
8156 longer needed. Keeping those around slows down things linearly.
8157 Note that this never removes the current inferior. */
8164 signal_stop_state (int signo
)
8166 return signal_stop
[signo
];
8170 signal_print_state (int signo
)
8172 return signal_print
[signo
];
8176 signal_pass_state (int signo
)
8178 return signal_program
[signo
];
8182 signal_cache_update (int signo
)
8186 for (signo
= 0; signo
< (int) GDB_SIGNAL_LAST
; signo
++)
8187 signal_cache_update (signo
);
8192 signal_pass
[signo
] = (signal_stop
[signo
] == 0
8193 && signal_print
[signo
] == 0
8194 && signal_program
[signo
] == 1
8195 && signal_catch
[signo
] == 0);
8199 signal_stop_update (int signo
, int state
)
8201 int ret
= signal_stop
[signo
];
8203 signal_stop
[signo
] = state
;
8204 signal_cache_update (signo
);
8209 signal_print_update (int signo
, int state
)
8211 int ret
= signal_print
[signo
];
8213 signal_print
[signo
] = state
;
8214 signal_cache_update (signo
);
8219 signal_pass_update (int signo
, int state
)
8221 int ret
= signal_program
[signo
];
8223 signal_program
[signo
] = state
;
8224 signal_cache_update (signo
);
8228 /* Update the global 'signal_catch' from INFO and notify the
8232 signal_catch_update (const unsigned int *info
)
8236 for (i
= 0; i
< GDB_SIGNAL_LAST
; ++i
)
8237 signal_catch
[i
] = info
[i
] > 0;
8238 signal_cache_update (-1);
8239 target_pass_signals (signal_pass
);
8243 sig_print_header (void)
8245 printf_filtered (_("Signal Stop\tPrint\tPass "
8246 "to program\tDescription\n"));
8250 sig_print_info (enum gdb_signal oursig
)
8252 const char *name
= gdb_signal_to_name (oursig
);
8253 int name_padding
= 13 - strlen (name
);
8255 if (name_padding
<= 0)
8258 printf_filtered ("%s", name
);
8259 printf_filtered ("%*.*s ", name_padding
, name_padding
, " ");
8260 printf_filtered ("%s\t", signal_stop
[oursig
] ? "Yes" : "No");
8261 printf_filtered ("%s\t", signal_print
[oursig
] ? "Yes" : "No");
8262 printf_filtered ("%s\t\t", signal_program
[oursig
] ? "Yes" : "No");
8263 printf_filtered ("%s\n", gdb_signal_to_string (oursig
));
8266 /* Specify how various signals in the inferior should be handled. */
8269 handle_command (const char *args
, int from_tty
)
8271 int digits
, wordlen
;
8272 int sigfirst
, siglast
;
8273 enum gdb_signal oursig
;
8278 error_no_arg (_("signal to handle"));
8281 /* Allocate and zero an array of flags for which signals to handle. */
8283 const size_t nsigs
= GDB_SIGNAL_LAST
;
8284 unsigned char sigs
[nsigs
] {};
8286 /* Break the command line up into args. */
8288 gdb_argv
built_argv (args
);
8290 /* Walk through the args, looking for signal oursigs, signal names, and
8291 actions. Signal numbers and signal names may be interspersed with
8292 actions, with the actions being performed for all signals cumulatively
8293 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
8295 for (char *arg
: built_argv
)
8297 wordlen
= strlen (arg
);
8298 for (digits
= 0; isdigit (arg
[digits
]); digits
++)
8302 sigfirst
= siglast
= -1;
8304 if (wordlen
>= 1 && !strncmp (arg
, "all", wordlen
))
8306 /* Apply action to all signals except those used by the
8307 debugger. Silently skip those. */
8310 siglast
= nsigs
- 1;
8312 else if (wordlen
>= 1 && !strncmp (arg
, "stop", wordlen
))
8314 SET_SIGS (nsigs
, sigs
, signal_stop
);
8315 SET_SIGS (nsigs
, sigs
, signal_print
);
8317 else if (wordlen
>= 1 && !strncmp (arg
, "ignore", wordlen
))
8319 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8321 else if (wordlen
>= 2 && !strncmp (arg
, "print", wordlen
))
8323 SET_SIGS (nsigs
, sigs
, signal_print
);
8325 else if (wordlen
>= 2 && !strncmp (arg
, "pass", wordlen
))
8327 SET_SIGS (nsigs
, sigs
, signal_program
);
8329 else if (wordlen
>= 3 && !strncmp (arg
, "nostop", wordlen
))
8331 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8333 else if (wordlen
>= 3 && !strncmp (arg
, "noignore", wordlen
))
8335 SET_SIGS (nsigs
, sigs
, signal_program
);
8337 else if (wordlen
>= 4 && !strncmp (arg
, "noprint", wordlen
))
8339 UNSET_SIGS (nsigs
, sigs
, signal_print
);
8340 UNSET_SIGS (nsigs
, sigs
, signal_stop
);
8342 else if (wordlen
>= 4 && !strncmp (arg
, "nopass", wordlen
))
8344 UNSET_SIGS (nsigs
, sigs
, signal_program
);
8346 else if (digits
> 0)
8348 /* It is numeric. The numeric signal refers to our own
8349 internal signal numbering from target.h, not to host/target
8350 signal number. This is a feature; users really should be
8351 using symbolic names anyway, and the common ones like
8352 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
8354 sigfirst
= siglast
= (int)
8355 gdb_signal_from_command (atoi (arg
));
8356 if (arg
[digits
] == '-')
8359 gdb_signal_from_command (atoi (arg
+ digits
+ 1));
8361 if (sigfirst
> siglast
)
8363 /* Bet he didn't figure we'd think of this case... */
8364 std::swap (sigfirst
, siglast
);
8369 oursig
= gdb_signal_from_name (arg
);
8370 if (oursig
!= GDB_SIGNAL_UNKNOWN
)
8372 sigfirst
= siglast
= (int) oursig
;
8376 /* Not a number and not a recognized flag word => complain. */
8377 error (_("Unrecognized or ambiguous flag word: \"%s\"."), arg
);
8381 /* If any signal numbers or symbol names were found, set flags for
8382 which signals to apply actions to. */
8384 for (int signum
= sigfirst
; signum
>= 0 && signum
<= siglast
; signum
++)
8386 switch ((enum gdb_signal
) signum
)
8388 case GDB_SIGNAL_TRAP
:
8389 case GDB_SIGNAL_INT
:
8390 if (!allsigs
&& !sigs
[signum
])
8392 if (query (_("%s is used by the debugger.\n\
8393 Are you sure you want to change it? "),
8394 gdb_signal_to_name ((enum gdb_signal
) signum
)))
8399 printf_unfiltered (_("Not confirmed, unchanged.\n"));
8403 case GDB_SIGNAL_DEFAULT
:
8404 case GDB_SIGNAL_UNKNOWN
:
8405 /* Make sure that "all" doesn't print these. */
8414 for (int signum
= 0; signum
< nsigs
; signum
++)
8417 signal_cache_update (-1);
8418 target_pass_signals (signal_pass
);
8419 target_program_signals (signal_program
);
8423 /* Show the results. */
8424 sig_print_header ();
8425 for (; signum
< nsigs
; signum
++)
8427 sig_print_info ((enum gdb_signal
) signum
);
8434 /* Complete the "handle" command. */
8437 handle_completer (struct cmd_list_element
*ignore
,
8438 completion_tracker
&tracker
,
8439 const char *text
, const char *word
)
8441 static const char * const keywords
[] =
8455 signal_completer (ignore
, tracker
, text
, word
);
8456 complete_on_enum (tracker
, keywords
, word
, word
);
8460 gdb_signal_from_command (int num
)
8462 if (num
>= 1 && num
<= 15)
8463 return (enum gdb_signal
) num
;
8464 error (_("Only signals 1-15 are valid as numeric signals.\n\
8465 Use \"info signals\" for a list of symbolic signals."));
8468 /* Print current contents of the tables set by the handle command.
8469 It is possible we should just be printing signals actually used
8470 by the current target (but for things to work right when switching
8471 targets, all signals should be in the signal tables). */
8474 info_signals_command (const char *signum_exp
, int from_tty
)
8476 enum gdb_signal oursig
;
8478 sig_print_header ();
8482 /* First see if this is a symbol name. */
8483 oursig
= gdb_signal_from_name (signum_exp
);
8484 if (oursig
== GDB_SIGNAL_UNKNOWN
)
8486 /* No, try numeric. */
8488 gdb_signal_from_command (parse_and_eval_long (signum_exp
));
8490 sig_print_info (oursig
);
8494 printf_filtered ("\n");
8495 /* These ugly casts brought to you by the native VAX compiler. */
8496 for (oursig
= GDB_SIGNAL_FIRST
;
8497 (int) oursig
< (int) GDB_SIGNAL_LAST
;
8498 oursig
= (enum gdb_signal
) ((int) oursig
+ 1))
8502 if (oursig
!= GDB_SIGNAL_UNKNOWN
8503 && oursig
!= GDB_SIGNAL_DEFAULT
&& oursig
!= GDB_SIGNAL_0
)
8504 sig_print_info (oursig
);
8507 printf_filtered (_("\nUse the \"handle\" command "
8508 "to change these tables.\n"));
8511 /* The $_siginfo convenience variable is a bit special. We don't know
8512 for sure the type of the value until we actually have a chance to
8513 fetch the data. The type can change depending on gdbarch, so it is
8514 also dependent on which thread you have selected.
8516 1. making $_siginfo be an internalvar that creates a new value on
8519 2. making the value of $_siginfo be an lval_computed value. */
8521 /* This function implements the lval_computed support for reading a
8525 siginfo_value_read (struct value
*v
)
8527 LONGEST transferred
;
8529 /* If we can access registers, so can we access $_siginfo. Likewise
8531 validate_registers_access ();
8534 target_read (current_top_target (), TARGET_OBJECT_SIGNAL_INFO
,
8536 value_contents_all_raw (v
),
8538 TYPE_LENGTH (value_type (v
)));
8540 if (transferred
!= TYPE_LENGTH (value_type (v
)))
8541 error (_("Unable to read siginfo"));
8544 /* This function implements the lval_computed support for writing a
8548 siginfo_value_write (struct value
*v
, struct value
*fromval
)
8550 LONGEST transferred
;
8552 /* If we can access registers, so can we access $_siginfo. Likewise
8554 validate_registers_access ();
8556 transferred
= target_write (current_top_target (),
8557 TARGET_OBJECT_SIGNAL_INFO
,
8559 value_contents_all_raw (fromval
),
8561 TYPE_LENGTH (value_type (fromval
)));
8563 if (transferred
!= TYPE_LENGTH (value_type (fromval
)))
8564 error (_("Unable to write siginfo"));
8567 static const struct lval_funcs siginfo_value_funcs
=
8573 /* Return a new value with the correct type for the siginfo object of
8574 the current thread using architecture GDBARCH. Return a void value
8575 if there's no object available. */
8577 static struct value
*
8578 siginfo_make_value (struct gdbarch
*gdbarch
, struct internalvar
*var
,
8581 if (target_has_stack
8582 && inferior_ptid
!= null_ptid
8583 && gdbarch_get_siginfo_type_p (gdbarch
))
8585 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8587 return allocate_computed_value (type
, &siginfo_value_funcs
, NULL
);
8590 return allocate_value (builtin_type (gdbarch
)->builtin_void
);
8594 /* infcall_suspend_state contains state about the program itself like its
8595 registers and any signal it received when it last stopped.
8596 This state must be restored regardless of how the inferior function call
8597 ends (either successfully, or after it hits a breakpoint or signal)
8598 if the program is to properly continue where it left off. */
8600 class infcall_suspend_state
8603 /* Capture state from GDBARCH, TP, and REGCACHE that must be restored
8604 once the inferior function call has finished. */
8605 infcall_suspend_state (struct gdbarch
*gdbarch
,
8606 const struct thread_info
*tp
,
8607 struct regcache
*regcache
)
8608 : m_thread_suspend (tp
->suspend
),
8609 m_registers (new readonly_detached_regcache (*regcache
))
8611 gdb::unique_xmalloc_ptr
<gdb_byte
> siginfo_data
;
8613 if (gdbarch_get_siginfo_type_p (gdbarch
))
8615 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8616 size_t len
= TYPE_LENGTH (type
);
8618 siginfo_data
.reset ((gdb_byte
*) xmalloc (len
));
8620 if (target_read (current_top_target (), TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8621 siginfo_data
.get (), 0, len
) != len
)
8623 /* Errors ignored. */
8624 siginfo_data
.reset (nullptr);
8630 m_siginfo_gdbarch
= gdbarch
;
8631 m_siginfo_data
= std::move (siginfo_data
);
8635 /* Return a pointer to the stored register state. */
8637 readonly_detached_regcache
*registers () const
8639 return m_registers
.get ();
8642 /* Restores the stored state into GDBARCH, TP, and REGCACHE. */
8644 void restore (struct gdbarch
*gdbarch
,
8645 struct thread_info
*tp
,
8646 struct regcache
*regcache
) const
8648 tp
->suspend
= m_thread_suspend
;
8650 if (m_siginfo_gdbarch
== gdbarch
)
8652 struct type
*type
= gdbarch_get_siginfo_type (gdbarch
);
8654 /* Errors ignored. */
8655 target_write (current_top_target (), TARGET_OBJECT_SIGNAL_INFO
, NULL
,
8656 m_siginfo_data
.get (), 0, TYPE_LENGTH (type
));
8659 /* The inferior can be gone if the user types "print exit(0)"
8660 (and perhaps other times). */
8661 if (target_has_execution
)
8662 /* NB: The register write goes through to the target. */
8663 regcache
->restore (registers ());
8667 /* How the current thread stopped before the inferior function call was
8669 struct thread_suspend_state m_thread_suspend
;
8671 /* The registers before the inferior function call was executed. */
8672 std::unique_ptr
<readonly_detached_regcache
> m_registers
;
8674 /* Format of SIGINFO_DATA or NULL if it is not present. */
8675 struct gdbarch
*m_siginfo_gdbarch
= nullptr;
8677 /* The inferior format depends on SIGINFO_GDBARCH and it has a length of
8678 TYPE_LENGTH (gdbarch_get_siginfo_type ()). For different gdbarch the
8679 content would be invalid. */
8680 gdb::unique_xmalloc_ptr
<gdb_byte
> m_siginfo_data
;
8683 infcall_suspend_state_up
8684 save_infcall_suspend_state ()
8686 struct thread_info
*tp
= inferior_thread ();
8687 struct regcache
*regcache
= get_current_regcache ();
8688 struct gdbarch
*gdbarch
= regcache
->arch ();
8690 infcall_suspend_state_up inf_state
8691 (new struct infcall_suspend_state (gdbarch
, tp
, regcache
));
8693 /* Having saved the current state, adjust the thread state, discarding
8694 any stop signal information. The stop signal is not useful when
8695 starting an inferior function call, and run_inferior_call will not use
8696 the signal due to its `proceed' call with GDB_SIGNAL_0. */
8697 tp
->suspend
.stop_signal
= GDB_SIGNAL_0
;
8702 /* Restore inferior session state to INF_STATE. */
8705 restore_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8707 struct thread_info
*tp
= inferior_thread ();
8708 struct regcache
*regcache
= get_current_regcache ();
8709 struct gdbarch
*gdbarch
= regcache
->arch ();
8711 inf_state
->restore (gdbarch
, tp
, regcache
);
8712 discard_infcall_suspend_state (inf_state
);
8716 discard_infcall_suspend_state (struct infcall_suspend_state
*inf_state
)
8721 readonly_detached_regcache
*
8722 get_infcall_suspend_state_regcache (struct infcall_suspend_state
*inf_state
)
8724 return inf_state
->registers ();
8727 /* infcall_control_state contains state regarding gdb's control of the
8728 inferior itself like stepping control. It also contains session state like
8729 the user's currently selected frame. */
8731 struct infcall_control_state
8733 struct thread_control_state thread_control
;
8734 struct inferior_control_state inferior_control
;
8737 enum stop_stack_kind stop_stack_dummy
= STOP_NONE
;
8738 int stopped_by_random_signal
= 0;
8740 /* ID if the selected frame when the inferior function call was made. */
8741 struct frame_id selected_frame_id
{};
8744 /* Save all of the information associated with the inferior<==>gdb
8747 infcall_control_state_up
8748 save_infcall_control_state ()
8750 infcall_control_state_up
inf_status (new struct infcall_control_state
);
8751 struct thread_info
*tp
= inferior_thread ();
8752 struct inferior
*inf
= current_inferior ();
8754 inf_status
->thread_control
= tp
->control
;
8755 inf_status
->inferior_control
= inf
->control
;
8757 tp
->control
.step_resume_breakpoint
= NULL
;
8758 tp
->control
.exception_resume_breakpoint
= NULL
;
8760 /* Save original bpstat chain to INF_STATUS; replace it in TP with copy of
8761 chain. If caller's caller is walking the chain, they'll be happier if we
8762 hand them back the original chain when restore_infcall_control_state is
8764 tp
->control
.stop_bpstat
= bpstat_copy (tp
->control
.stop_bpstat
);
8767 inf_status
->stop_stack_dummy
= stop_stack_dummy
;
8768 inf_status
->stopped_by_random_signal
= stopped_by_random_signal
;
8770 inf_status
->selected_frame_id
= get_frame_id (get_selected_frame (NULL
));
8776 restore_selected_frame (const frame_id
&fid
)
8778 frame_info
*frame
= frame_find_by_id (fid
);
8780 /* If inf_status->selected_frame_id is NULL, there was no previously
8784 warning (_("Unable to restore previously selected frame."));
8788 select_frame (frame
);
8791 /* Restore inferior session state to INF_STATUS. */
8794 restore_infcall_control_state (struct infcall_control_state
*inf_status
)
8796 struct thread_info
*tp
= inferior_thread ();
8797 struct inferior
*inf
= current_inferior ();
8799 if (tp
->control
.step_resume_breakpoint
)
8800 tp
->control
.step_resume_breakpoint
->disposition
= disp_del_at_next_stop
;
8802 if (tp
->control
.exception_resume_breakpoint
)
8803 tp
->control
.exception_resume_breakpoint
->disposition
8804 = disp_del_at_next_stop
;
8806 /* Handle the bpstat_copy of the chain. */
8807 bpstat_clear (&tp
->control
.stop_bpstat
);
8809 tp
->control
= inf_status
->thread_control
;
8810 inf
->control
= inf_status
->inferior_control
;
8813 stop_stack_dummy
= inf_status
->stop_stack_dummy
;
8814 stopped_by_random_signal
= inf_status
->stopped_by_random_signal
;
8816 if (target_has_stack
)
8818 /* The point of the try/catch is that if the stack is clobbered,
8819 walking the stack might encounter a garbage pointer and
8820 error() trying to dereference it. */
8823 restore_selected_frame (inf_status
->selected_frame_id
);
8825 catch (const gdb_exception_error
&ex
)
8827 exception_fprintf (gdb_stderr
, ex
,
8828 "Unable to restore previously selected frame:\n");
8829 /* Error in restoring the selected frame. Select the
8831 select_frame (get_current_frame ());
8839 discard_infcall_control_state (struct infcall_control_state
*inf_status
)
8841 if (inf_status
->thread_control
.step_resume_breakpoint
)
8842 inf_status
->thread_control
.step_resume_breakpoint
->disposition
8843 = disp_del_at_next_stop
;
8845 if (inf_status
->thread_control
.exception_resume_breakpoint
)
8846 inf_status
->thread_control
.exception_resume_breakpoint
->disposition
8847 = disp_del_at_next_stop
;
8849 /* See save_infcall_control_state for info on stop_bpstat. */
8850 bpstat_clear (&inf_status
->thread_control
.stop_bpstat
);
8858 clear_exit_convenience_vars (void)
8860 clear_internalvar (lookup_internalvar ("_exitsignal"));
8861 clear_internalvar (lookup_internalvar ("_exitcode"));
8865 /* User interface for reverse debugging:
8866 Set exec-direction / show exec-direction commands
8867 (returns error unless target implements to_set_exec_direction method). */
8869 enum exec_direction_kind execution_direction
= EXEC_FORWARD
;
8870 static const char exec_forward
[] = "forward";
8871 static const char exec_reverse
[] = "reverse";
8872 static const char *exec_direction
= exec_forward
;
8873 static const char *const exec_direction_names
[] = {
8880 set_exec_direction_func (const char *args
, int from_tty
,
8881 struct cmd_list_element
*cmd
)
8883 if (target_can_execute_reverse
)
8885 if (!strcmp (exec_direction
, exec_forward
))
8886 execution_direction
= EXEC_FORWARD
;
8887 else if (!strcmp (exec_direction
, exec_reverse
))
8888 execution_direction
= EXEC_REVERSE
;
8892 exec_direction
= exec_forward
;
8893 error (_("Target does not support this operation."));
8898 show_exec_direction_func (struct ui_file
*out
, int from_tty
,
8899 struct cmd_list_element
*cmd
, const char *value
)
8901 switch (execution_direction
) {
8903 fprintf_filtered (out
, _("Forward.\n"));
8906 fprintf_filtered (out
, _("Reverse.\n"));
8909 internal_error (__FILE__
, __LINE__
,
8910 _("bogus execution_direction value: %d"),
8911 (int) execution_direction
);
8916 show_schedule_multiple (struct ui_file
*file
, int from_tty
,
8917 struct cmd_list_element
*c
, const char *value
)
8919 fprintf_filtered (file
, _("Resuming the execution of threads "
8920 "of all processes is %s.\n"), value
);
8923 /* Implementation of `siginfo' variable. */
8925 static const struct internalvar_funcs siginfo_funcs
=
8932 /* Callback for infrun's target events source. This is marked when a
8933 thread has a pending status to process. */
8936 infrun_async_inferior_event_handler (gdb_client_data data
)
8938 inferior_event_handler (INF_REG_EVENT
, NULL
);
8942 _initialize_infrun (void)
8944 struct cmd_list_element
*c
;
8946 /* Register extra event sources in the event loop. */
8947 infrun_async_inferior_event_token
8948 = create_async_event_handler (infrun_async_inferior_event_handler
, NULL
);
8950 add_info ("signals", info_signals_command
, _("\
8951 What debugger does when program gets various signals.\n\
8952 Specify a signal as argument to print info on that signal only."));
8953 add_info_alias ("handle", "signals", 0);
8955 c
= add_com ("handle", class_run
, handle_command
, _("\
8956 Specify how to handle signals.\n\
8957 Usage: handle SIGNAL [ACTIONS]\n\
8958 Args are signals and actions to apply to those signals.\n\
8959 If no actions are specified, the current settings for the specified signals\n\
8960 will be displayed instead.\n\
8962 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
8963 from 1-15 are allowed for compatibility with old versions of GDB.\n\
8964 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
8965 The special arg \"all\" is recognized to mean all signals except those\n\
8966 used by the debugger, typically SIGTRAP and SIGINT.\n\
8968 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
8969 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
8970 Stop means reenter debugger if this signal happens (implies print).\n\
8971 Print means print a message if this signal happens.\n\
8972 Pass means let program see this signal; otherwise program doesn't know.\n\
8973 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
8974 Pass and Stop may be combined.\n\
8976 Multiple signals may be specified. Signal numbers and signal names\n\
8977 may be interspersed with actions, with the actions being performed for\n\
8978 all signals cumulatively specified."));
8979 set_cmd_completer (c
, handle_completer
);
8982 stop_command
= add_cmd ("stop", class_obscure
,
8983 not_just_help_class_command
, _("\
8984 There is no `stop' command, but you can set a hook on `stop'.\n\
8985 This allows you to set a list of commands to be run each time execution\n\
8986 of the program stops."), &cmdlist
);
8988 add_setshow_zuinteger_cmd ("infrun", class_maintenance
, &debug_infrun
, _("\
8989 Set inferior debugging."), _("\
8990 Show inferior debugging."), _("\
8991 When non-zero, inferior specific debugging is enabled."),
8994 &setdebuglist
, &showdebuglist
);
8996 add_setshow_boolean_cmd ("displaced", class_maintenance
,
8997 &debug_displaced
, _("\
8998 Set displaced stepping debugging."), _("\
8999 Show displaced stepping debugging."), _("\
9000 When non-zero, displaced stepping specific debugging is enabled."),
9002 show_debug_displaced
,
9003 &setdebuglist
, &showdebuglist
);
9005 add_setshow_boolean_cmd ("non-stop", no_class
,
9007 Set whether gdb controls the inferior in non-stop mode."), _("\
9008 Show whether gdb controls the inferior in non-stop mode."), _("\
9009 When debugging a multi-threaded program and this setting is\n\
9010 off (the default, also called all-stop mode), when one thread stops\n\
9011 (for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
9012 all other threads in the program while you interact with the thread of\n\
9013 interest. When you continue or step a thread, you can allow the other\n\
9014 threads to run, or have them remain stopped, but while you inspect any\n\
9015 thread's state, all threads stop.\n\
9017 In non-stop mode, when one thread stops, other threads can continue\n\
9018 to run freely. You'll be able to step each thread independently,\n\
9019 leave it stopped or free to run as needed."),
9025 for (size_t i
= 0; i
< GDB_SIGNAL_LAST
; i
++)
9028 signal_print
[i
] = 1;
9029 signal_program
[i
] = 1;
9030 signal_catch
[i
] = 0;
9033 /* Signals caused by debugger's own actions should not be given to
9034 the program afterwards.
9036 Do not deliver GDB_SIGNAL_TRAP by default, except when the user
9037 explicitly specifies that it should be delivered to the target
9038 program. Typically, that would occur when a user is debugging a
9039 target monitor on a simulator: the target monitor sets a
9040 breakpoint; the simulator encounters this breakpoint and halts
9041 the simulation handing control to GDB; GDB, noting that the stop
9042 address doesn't map to any known breakpoint, returns control back
9043 to the simulator; the simulator then delivers the hardware
9044 equivalent of a GDB_SIGNAL_TRAP to the program being
9046 signal_program
[GDB_SIGNAL_TRAP
] = 0;
9047 signal_program
[GDB_SIGNAL_INT
] = 0;
9049 /* Signals that are not errors should not normally enter the debugger. */
9050 signal_stop
[GDB_SIGNAL_ALRM
] = 0;
9051 signal_print
[GDB_SIGNAL_ALRM
] = 0;
9052 signal_stop
[GDB_SIGNAL_VTALRM
] = 0;
9053 signal_print
[GDB_SIGNAL_VTALRM
] = 0;
9054 signal_stop
[GDB_SIGNAL_PROF
] = 0;
9055 signal_print
[GDB_SIGNAL_PROF
] = 0;
9056 signal_stop
[GDB_SIGNAL_CHLD
] = 0;
9057 signal_print
[GDB_SIGNAL_CHLD
] = 0;
9058 signal_stop
[GDB_SIGNAL_IO
] = 0;
9059 signal_print
[GDB_SIGNAL_IO
] = 0;
9060 signal_stop
[GDB_SIGNAL_POLL
] = 0;
9061 signal_print
[GDB_SIGNAL_POLL
] = 0;
9062 signal_stop
[GDB_SIGNAL_URG
] = 0;
9063 signal_print
[GDB_SIGNAL_URG
] = 0;
9064 signal_stop
[GDB_SIGNAL_WINCH
] = 0;
9065 signal_print
[GDB_SIGNAL_WINCH
] = 0;
9066 signal_stop
[GDB_SIGNAL_PRIO
] = 0;
9067 signal_print
[GDB_SIGNAL_PRIO
] = 0;
9069 /* These signals are used internally by user-level thread
9070 implementations. (See signal(5) on Solaris.) Like the above
9071 signals, a healthy program receives and handles them as part of
9072 its normal operation. */
9073 signal_stop
[GDB_SIGNAL_LWP
] = 0;
9074 signal_print
[GDB_SIGNAL_LWP
] = 0;
9075 signal_stop
[GDB_SIGNAL_WAITING
] = 0;
9076 signal_print
[GDB_SIGNAL_WAITING
] = 0;
9077 signal_stop
[GDB_SIGNAL_CANCEL
] = 0;
9078 signal_print
[GDB_SIGNAL_CANCEL
] = 0;
9079 signal_stop
[GDB_SIGNAL_LIBRT
] = 0;
9080 signal_print
[GDB_SIGNAL_LIBRT
] = 0;
9082 /* Update cached state. */
9083 signal_cache_update (-1);
9085 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support
,
9086 &stop_on_solib_events
, _("\
9087 Set stopping for shared library events."), _("\
9088 Show stopping for shared library events."), _("\
9089 If nonzero, gdb will give control to the user when the dynamic linker\n\
9090 notifies gdb of shared library events. The most common event of interest\n\
9091 to the user would be loading/unloading of a new library."),
9092 set_stop_on_solib_events
,
9093 show_stop_on_solib_events
,
9094 &setlist
, &showlist
);
9096 add_setshow_enum_cmd ("follow-fork-mode", class_run
,
9097 follow_fork_mode_kind_names
,
9098 &follow_fork_mode_string
, _("\
9099 Set debugger response to a program call of fork or vfork."), _("\
9100 Show debugger response to a program call of fork or vfork."), _("\
9101 A fork or vfork creates a new process. follow-fork-mode can be:\n\
9102 parent - the original process is debugged after a fork\n\
9103 child - the new process is debugged after a fork\n\
9104 The unfollowed process will continue to run.\n\
9105 By default, the debugger will follow the parent process."),
9107 show_follow_fork_mode_string
,
9108 &setlist
, &showlist
);
9110 add_setshow_enum_cmd ("follow-exec-mode", class_run
,
9111 follow_exec_mode_names
,
9112 &follow_exec_mode_string
, _("\
9113 Set debugger response to a program call of exec."), _("\
9114 Show debugger response to a program call of exec."), _("\
9115 An exec call replaces the program image of a process.\n\
9117 follow-exec-mode can be:\n\
9119 new - the debugger creates a new inferior and rebinds the process\n\
9120 to this new inferior. The program the process was running before\n\
9121 the exec call can be restarted afterwards by restarting the original\n\
9124 same - the debugger keeps the process bound to the same inferior.\n\
9125 The new executable image replaces the previous executable loaded in\n\
9126 the inferior. Restarting the inferior after the exec call restarts\n\
9127 the executable the process was running after the exec call.\n\
9129 By default, the debugger will use the same inferior."),
9131 show_follow_exec_mode_string
,
9132 &setlist
, &showlist
);
9134 add_setshow_enum_cmd ("scheduler-locking", class_run
,
9135 scheduler_enums
, &scheduler_mode
, _("\
9136 Set mode for locking scheduler during execution."), _("\
9137 Show mode for locking scheduler during execution."), _("\
9138 off == no locking (threads may preempt at any time)\n\
9139 on == full locking (no thread except the current thread may run)\n\
9140 This applies to both normal execution and replay mode.\n\
9141 step == scheduler locked during stepping commands (step, next, stepi, nexti).\n\
9142 In this mode, other threads may run during other commands.\n\
9143 This applies to both normal execution and replay mode.\n\
9144 replay == scheduler locked in replay mode and unlocked during normal execution."),
9145 set_schedlock_func
, /* traps on target vector */
9146 show_scheduler_mode
,
9147 &setlist
, &showlist
);
9149 add_setshow_boolean_cmd ("schedule-multiple", class_run
, &sched_multi
, _("\
9150 Set mode for resuming threads of all processes."), _("\
9151 Show mode for resuming threads of all processes."), _("\
9152 When on, execution commands (such as 'continue' or 'next') resume all\n\
9153 threads of all processes. When off (which is the default), execution\n\
9154 commands only resume the threads of the current process. The set of\n\
9155 threads that are resumed is further refined by the scheduler-locking\n\
9156 mode (see help set scheduler-locking)."),
9158 show_schedule_multiple
,
9159 &setlist
, &showlist
);
9161 add_setshow_boolean_cmd ("step-mode", class_run
, &step_stop_if_no_debug
, _("\
9162 Set mode of the step operation."), _("\
9163 Show mode of the step operation."), _("\
9164 When set, doing a step over a function without debug line information\n\
9165 will stop at the first instruction of that function. Otherwise, the\n\
9166 function is skipped and the step command stops at a different source line."),
9168 show_step_stop_if_no_debug
,
9169 &setlist
, &showlist
);
9171 add_setshow_auto_boolean_cmd ("displaced-stepping", class_run
,
9172 &can_use_displaced_stepping
, _("\
9173 Set debugger's willingness to use displaced stepping."), _("\
9174 Show debugger's willingness to use displaced stepping."), _("\
9175 If on, gdb will use displaced stepping to step over breakpoints if it is\n\
9176 supported by the target architecture. If off, gdb will not use displaced\n\
9177 stepping to step over breakpoints, even if such is supported by the target\n\
9178 architecture. If auto (which is the default), gdb will use displaced stepping\n\
9179 if the target architecture supports it and non-stop mode is active, but will not\n\
9180 use it in all-stop mode (see help set non-stop)."),
9182 show_can_use_displaced_stepping
,
9183 &setlist
, &showlist
);
9185 add_setshow_enum_cmd ("exec-direction", class_run
, exec_direction_names
,
9186 &exec_direction
, _("Set direction of execution.\n\
9187 Options are 'forward' or 'reverse'."),
9188 _("Show direction of execution (forward/reverse)."),
9189 _("Tells gdb whether to execute forward or backward."),
9190 set_exec_direction_func
, show_exec_direction_func
,
9191 &setlist
, &showlist
);
9193 /* Set/show detach-on-fork: user-settable mode. */
9195 add_setshow_boolean_cmd ("detach-on-fork", class_run
, &detach_fork
, _("\
9196 Set whether gdb will detach the child of a fork."), _("\
9197 Show whether gdb will detach the child of a fork."), _("\
9198 Tells gdb whether to detach the child of a fork."),
9199 NULL
, NULL
, &setlist
, &showlist
);
9201 /* Set/show disable address space randomization mode. */
9203 add_setshow_boolean_cmd ("disable-randomization", class_support
,
9204 &disable_randomization
, _("\
9205 Set disabling of debuggee's virtual address space randomization."), _("\
9206 Show disabling of debuggee's virtual address space randomization."), _("\
9207 When this mode is on (which is the default), randomization of the virtual\n\
9208 address space is disabled. Standalone programs run with the randomization\n\
9209 enabled by default on some platforms."),
9210 &set_disable_randomization
,
9211 &show_disable_randomization
,
9212 &setlist
, &showlist
);
9214 /* ptid initializations */
9215 inferior_ptid
= null_ptid
;
9216 target_last_wait_ptid
= minus_one_ptid
;
9218 gdb::observers::thread_ptid_changed
.attach (infrun_thread_ptid_changed
);
9219 gdb::observers::thread_stop_requested
.attach (infrun_thread_stop_requested
);
9220 gdb::observers::thread_exit
.attach (infrun_thread_thread_exit
);
9221 gdb::observers::inferior_exit
.attach (infrun_inferior_exit
);
9223 /* Explicitly create without lookup, since that tries to create a
9224 value with a void typed value, and when we get here, gdbarch
9225 isn't initialized yet. At this point, we're quite sure there
9226 isn't another convenience variable of the same name. */
9227 create_internalvar_type_lazy ("_siginfo", &siginfo_funcs
, NULL
);
9229 add_setshow_boolean_cmd ("observer", no_class
,
9230 &observer_mode_1
, _("\
9231 Set whether gdb controls the inferior in observer mode."), _("\
9232 Show whether gdb controls the inferior in observer mode."), _("\
9233 In observer mode, GDB can get data from the inferior, but not\n\
9234 affect its execution. Registers and memory may not be changed,\n\
9235 breakpoints may not be set, and the program cannot be interrupted\n\