/* Target-struct-independent code to start (run) and stop an inferior
process.
- Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994,
- 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
- 2006
- Free Software Foundation, Inc.
+ Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
+ 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
+ 2008, 2009 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
+ the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 51 Franklin Street, Fifth Floor,
- Boston, MA 02110-1301, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "gdb_string.h"
#include "language.h"
#include "solib.h"
#include "main.h"
-
#include "gdb_assert.h"
#include "mi/mi-common.h"
+#include "event-top.h"
+#include "record.h"
+#include "inline-frame.h"
/* Prototypes for local functions */
static void set_schedlock_func (char *args, int from_tty,
struct cmd_list_element *c);
-struct execution_control_state;
+static int currently_stepping (struct thread_info *tp);
-static int currently_stepping (struct execution_control_state *ecs);
+static int currently_stepping_or_nexting_callback (struct thread_info *tp,
+ void *data);
static void xdb_handle_command (char *args, int from_tty);
-static int prepare_to_proceed (void);
+static int prepare_to_proceed (int);
void _initialize_infrun (void);
-int inferior_ignoring_startup_exec_events = 0;
-int inferior_ignoring_leading_exec_events = 0;
+void nullify_last_target_wait_ptid (void);
/* When set, stop the 'step' command if we enter a function which has
no line number information. The normal behavior is that we step
static ptid_t previous_inferior_ptid;
-/* This is true for configurations that may follow through execl() and
- similar functions. At present this is only true for HP-UX native. */
-
-#ifndef MAY_FOLLOW_EXEC
-#define MAY_FOLLOW_EXEC (0)
-#endif
-
-static int may_follow_exec = MAY_FOLLOW_EXEC;
+int debug_displaced = 0;
+static void
+show_debug_displaced (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c, const char *value)
+{
+ fprintf_filtered (file, _("Displace stepping debugging is %s.\n"), value);
+}
static int debug_infrun = 0;
static void
past the dynamic linker, as if we were using "next" to step over a
function call.
- IN_SOLIB_DYNSYM_RESOLVE_CODE says whether we're in the dynamic
+ in_solib_dynsym_resolve_code() says whether we're in the dynamic
linker code or not. Normally, this means we single-step. However,
if SKIP_SOLIB_RESOLVER then returns non-zero, then its value is an
address where we can place a step-resume breakpoint to get past the
linker's symbol resolution function.
- IN_SOLIB_DYNSYM_RESOLVE_CODE can generally be implemented in a
+ in_solib_dynsym_resolve_code() can generally be implemented in a
pretty portable way, by comparing the PC against the address ranges
of the dynamic linker's sections.
#define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0
#endif
-/* We can't step off a permanent breakpoint in the ordinary way, because we
- can't remove it. Instead, we have to advance the PC to the next
- instruction. This macro should expand to a pointer to a function that
- does that, or zero if we have no such function. If we don't have a
- definition for it, we have to report an error. */
-#ifndef SKIP_PERMANENT_BREAKPOINT
-#define SKIP_PERMANENT_BREAKPOINT (default_skip_permanent_breakpoint)
-static void
-default_skip_permanent_breakpoint (void)
-{
- error (_("\
-The program is stopped at a permanent breakpoint, but GDB does not know\n\
-how to step past a permanent breakpoint on this architecture. Try using\n\
-a command like `return' or `jump' to continue execution."));
-}
-#endif
-
/* Convert the #defines into values. This is temporary until wfi control
flow is completely sorted out. */
-#ifndef HAVE_STEPPABLE_WATCHPOINT
-#define HAVE_STEPPABLE_WATCHPOINT 0
-#else
-#undef HAVE_STEPPABLE_WATCHPOINT
-#define HAVE_STEPPABLE_WATCHPOINT 1
-#endif
-
#ifndef CANNOT_STEP_HW_WATCHPOINTS
#define CANNOT_STEP_HW_WATCHPOINTS 0
#else
/* Value to pass to target_resume() to cause all threads to resume */
-#define RESUME_ALL (pid_to_ptid (-1))
+#define RESUME_ALL minus_one_ptid
/* Command list pointer for the "stop" placeholder. */
static struct cmd_list_element *stop_command;
-/* Nonzero if breakpoints are now inserted in the inferior. */
-
-static int breakpoints_inserted;
-
/* Function inferior was in as of last step command. */
static struct symbol *step_start_function;
-/* Nonzero if we are expecting a trace trap and should proceed from it. */
-
-static int trap_expected;
-
/* Nonzero if we want to give control to the user when we're notified
of shared library events by the dynamic linker. */
static int stop_on_solib_events;
int stop_after_trap;
-/* Nonzero means expecting a trap and caller will handle it themselves.
- It is used after attach, due to attaching to a process;
- when running in the shell before the child program has been exec'd;
- and when running some kinds of remote stuff (FIXME?). */
-
-enum stop_kind stop_soon;
-
-/* Nonzero if proceed is being used for a "finish" command or a similar
- situation when stop_registers should be saved. */
-
-int proceed_to_finish;
-
-/* Save register contents here when about to pop a stack dummy frame,
- if-and-only-if proceed_to_finish is set.
+/* Save register contents here when executing a "finish" command or are
+ about to pop a stack dummy frame, if-and-only-if proceed_to_finish is set.
Thus this contains the return value from the called function (assuming
values are returned in a register). */
struct regcache *stop_registers;
-/* Nonzero if program stopped due to error trying to insert breakpoints. */
-
-static int breakpoints_failed;
-
/* Nonzero after stop if current stack frame should be printed. */
static int stop_print_frame;
-static struct breakpoint *step_resume_breakpoint = NULL;
-
/* This is a cached copy of the pid/waitstatus of the last event
returned by target_wait()/deprecated_target_wait_hook(). This
information is returned by get_last_target_status(). */
static ptid_t target_last_wait_ptid;
static struct target_waitstatus target_last_waitstatus;
-/* This is used to remember when a fork, vfork or exec event
- was caught by a catchpoint, and thus the event is to be
- followed at the next resume of the inferior, and not
- immediately. */
-static struct
-{
- enum target_waitkind kind;
- struct
- {
- int parent_pid;
- int child_pid;
- }
- fork_event;
- char *execd_pathname;
-}
-pending_follow;
+static void context_switch (ptid_t ptid);
+
+void init_thread_stepping_state (struct thread_info *tss);
+
+void init_infwait_state (void);
static const char follow_fork_mode_child[] = "child";
static const char follow_fork_mode_parent[] = "parent";
}
\f
+/* Tell the target to follow the fork we're stopped at. Returns true
+ if the inferior should be resumed; false, if the target for some
+ reason decided it's best not to resume. */
+
static int
follow_fork (void)
{
int follow_child = (follow_fork_mode_string == follow_fork_mode_child);
+ int should_resume = 1;
+ struct thread_info *tp;
+
+ /* Copy user stepping state to the new inferior thread. FIXME: the
+ followed fork child thread should have a copy of most of the
+ parent thread structure's run control related fields, not just these.
+ Initialized to avoid "may be used uninitialized" warnings from gcc. */
+ struct breakpoint *step_resume_breakpoint = NULL;
+ CORE_ADDR step_range_start = 0;
+ CORE_ADDR step_range_end = 0;
+ struct frame_id step_frame_id = { 0 };
+
+ if (!non_stop)
+ {
+ ptid_t wait_ptid;
+ struct target_waitstatus wait_status;
+
+ /* Get the last target status returned by target_wait(). */
+ get_last_target_status (&wait_ptid, &wait_status);
+
+ /* If not stopped at a fork event, then there's nothing else to
+ do. */
+ if (wait_status.kind != TARGET_WAITKIND_FORKED
+ && wait_status.kind != TARGET_WAITKIND_VFORKED)
+ return 1;
+
+ /* Check if we switched over from WAIT_PTID, since the event was
+ reported. */
+ if (!ptid_equal (wait_ptid, minus_one_ptid)
+ && !ptid_equal (inferior_ptid, wait_ptid))
+ {
+ /* We did. Switch back to WAIT_PTID thread, to tell the
+ target to follow it (in either direction). We'll
+ afterwards refuse to resume, and inform the user what
+ happened. */
+ switch_to_thread (wait_ptid);
+ should_resume = 0;
+ }
+ }
+
+ tp = inferior_thread ();
+
+ /* If there were any forks/vforks that were caught and are now to be
+ followed, then do so now. */
+ switch (tp->pending_follow.kind)
+ {
+ case TARGET_WAITKIND_FORKED:
+ case TARGET_WAITKIND_VFORKED:
+ {
+ ptid_t parent, child;
+
+ /* If the user did a next/step, etc, over a fork call,
+ preserve the stepping state in the fork child. */
+ if (follow_child && should_resume)
+ {
+ step_resume_breakpoint
+ = clone_momentary_breakpoint (tp->step_resume_breakpoint);
+ step_range_start = tp->step_range_start;
+ step_range_end = tp->step_range_end;
+ step_frame_id = tp->step_frame_id;
+
+ /* For now, delete the parent's sr breakpoint, otherwise,
+ parent/child sr breakpoints are considered duplicates,
+ and the child version will not be installed. Remove
+ this when the breakpoints module becomes aware of
+ inferiors and address spaces. */
+ delete_step_resume_breakpoint (tp);
+ tp->step_range_start = 0;
+ tp->step_range_end = 0;
+ tp->step_frame_id = null_frame_id;
+ }
+
+ parent = inferior_ptid;
+ child = tp->pending_follow.value.related_pid;
+
+ /* Tell the target to do whatever is necessary to follow
+ either parent or child. */
+ if (target_follow_fork (follow_child))
+ {
+ /* Target refused to follow, or there's some other reason
+ we shouldn't resume. */
+ should_resume = 0;
+ }
+ else
+ {
+ /* This pending follow fork event is now handled, one way
+ or another. The previous selected thread may be gone
+ from the lists by now, but if it is still around, need
+ to clear the pending follow request. */
+ tp = find_thread_ptid (parent);
+ if (tp)
+ tp->pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
+
+ /* This makes sure we don't try to apply the "Switched
+ over from WAIT_PID" logic above. */
+ nullify_last_target_wait_ptid ();
+
+ /* If we followed the child, switch to it... */
+ if (follow_child)
+ {
+ switch_to_thread (child);
+
+ /* ... and preserve the stepping state, in case the
+ user was stepping over the fork call. */
+ if (should_resume)
+ {
+ tp = inferior_thread ();
+ tp->step_resume_breakpoint = step_resume_breakpoint;
+ tp->step_range_start = step_range_start;
+ tp->step_range_end = step_range_end;
+ tp->step_frame_id = step_frame_id;
+ }
+ else
+ {
+ /* If we get here, it was because we're trying to
+ resume from a fork catchpoint, but, the user
+ has switched threads away from the thread that
+ forked. In that case, the resume command
+ issued is most likely not applicable to the
+ child, so just warn, and refuse to resume. */
+ warning (_("\
+Not resuming: switched threads before following fork child.\n"));
+ }
+
+ /* Reset breakpoints in the child as appropriate. */
+ follow_inferior_reset_breakpoints ();
+ }
+ else
+ switch_to_thread (parent);
+ }
+ }
+ break;
+ case TARGET_WAITKIND_SPURIOUS:
+ /* Nothing to follow. */
+ break;
+ default:
+ internal_error (__FILE__, __LINE__,
+ "Unexpected pending_follow.kind %d\n",
+ tp->pending_follow.kind);
+ break;
+ }
- return target_follow_fork (follow_child);
+ return should_resume;
}
void
follow_inferior_reset_breakpoints (void)
{
+ struct thread_info *tp = inferior_thread ();
+
/* Was there a step_resume breakpoint? (There was if the user
did a "next" at the fork() call.) If so, explicitly reset its
thread number.
"threads". We must update the bp's notion of which thread
it is for, or it'll be ignored when it triggers. */
- if (step_resume_breakpoint)
- breakpoint_re_set_thread (step_resume_breakpoint);
+ if (tp->step_resume_breakpoint)
+ breakpoint_re_set_thread (tp->step_resume_breakpoint);
/* Reinsert all breakpoints in the child. The user may have set
breakpoints after catching the fork, in which case those
/* EXECD_PATHNAME is assumed to be non-NULL. */
static void
-follow_exec (int pid, char *execd_pathname)
+follow_exec (ptid_t pid, char *execd_pathname)
{
- int saved_pid = pid;
struct target_ops *tgt;
-
- if (!may_follow_exec)
- return;
+ struct thread_info *th = inferior_thread ();
/* This is an exec event that we actually wish to pay attention to.
Refresh our symbol table to the newly exec'd program, remove any
/* If there was one, it's gone now. We cannot truly step-to-next
statement through an exec(). */
- step_resume_breakpoint = NULL;
- step_range_start = 0;
- step_range_end = 0;
+ th->step_resume_breakpoint = NULL;
+ th->step_range_start = 0;
+ th->step_range_end = 0;
+
+ /* The target reports the exec event to the main thread, even if
+ some other thread does the exec, and even if the main thread was
+ already stopped --- if debugging in non-stop mode, it's possible
+ the user had the main thread held stopped in the previous image
+ --- release it now. This is the same behavior as step-over-exec
+ with scheduler-locking on in all-stop mode. */
+ th->stop_requested = 0;
/* What is this a.out's name? */
printf_unfiltered (_("Executing new program: %s\n"), execd_pathname);
/* We've followed the inferior through an exec. Therefore, the
inferior has essentially been killed & reborn. */
- /* First collect the run target in effect. */
- tgt = find_run_target ();
- /* If we can't find one, things are in a very strange state... */
- if (tgt == NULL)
- error (_("Could find run target to save before following exec"));
-
gdb_flush (gdb_stdout);
- target_mourn_inferior ();
- inferior_ptid = pid_to_ptid (saved_pid);
- /* Because mourn_inferior resets inferior_ptid. */
- push_target (tgt);
+
+ breakpoint_init_inferior (inf_execd);
+
+ if (gdb_sysroot && *gdb_sysroot)
+ {
+ char *name = alloca (strlen (gdb_sysroot)
+ + strlen (execd_pathname)
+ + 1);
+ strcpy (name, gdb_sysroot);
+ strcat (name, execd_pathname);
+ execd_pathname = name;
+ }
/* That a.out is now the one to use. */
exec_file_attach (execd_pathname, 0);
- /* And also is where symbols can be found. */
+ /* Reset the shared library package. This ensures that we get a
+ shlib event when the child reaches "_start", at which point the
+ dld will have had a chance to initialize the child. */
+ /* Also, loading a symbol file below may trigger symbol lookups, and
+ we don't want those to be satisfied by the libraries of the
+ previous incarnation of this process. */
+ no_shared_libraries (NULL, 0);
+
+ /* Load the main file's symbols. */
symbol_file_add_main (execd_pathname, 0);
- /* Reset the shared library package. This ensures that we get
- a shlib event when the child reaches "_start", at which point
- the dld will have had a chance to initialize the child. */
-#if defined(SOLIB_RESTART)
- SOLIB_RESTART ();
-#endif
#ifdef SOLIB_CREATE_INFERIOR_HOOK
SOLIB_CREATE_INFERIOR_HOOK (PIDGET (inferior_ptid));
#else
/* The thread we inserted single-step breakpoints for. */
static ptid_t singlestep_ptid;
+/* PC when we started this single-step. */
+static CORE_ADDR singlestep_pc;
+
/* If another thread hit the singlestep breakpoint, we save the original
thread here so that we can resume single-stepping it later. */
static ptid_t saved_singlestep_ptid;
static int stepping_past_singlestep_breakpoint;
+
+/* If not equal to null_ptid, this means that after stepping over breakpoint
+ is finished, we need to switch to deferred_step_ptid, and step it.
+
+ The use case is when one thread has hit a breakpoint, and then the user
+ has switched to another thread and issued 'step'. We need to step over
+ breakpoint in the thread which hit the breakpoint, but then continue
+ stepping the thread user has selected. */
+static ptid_t deferred_step_ptid;
+\f
+/* Displaced stepping. */
+
+/* In non-stop debugging mode, we must take special care to manage
+ breakpoints properly; in particular, the traditional strategy for
+ stepping a thread past a breakpoint it has hit is unsuitable.
+ 'Displaced stepping' is a tactic for stepping one thread past a
+ breakpoint it has hit while ensuring that other threads running
+ concurrently will hit the breakpoint as they should.
+
+ The traditional way to step a thread T off a breakpoint in a
+ multi-threaded program in all-stop mode is as follows:
+
+ a0) Initially, all threads are stopped, and breakpoints are not
+ inserted.
+ a1) We single-step T, leaving breakpoints uninserted.
+ a2) We insert breakpoints, and resume all threads.
+
+ In non-stop debugging, however, this strategy is unsuitable: we
+ don't want to have to stop all threads in the system in order to
+ continue or step T past a breakpoint. Instead, we use displaced
+ stepping:
+
+ n0) Initially, T is stopped, other threads are running, and
+ breakpoints are inserted.
+ n1) We copy the instruction "under" the breakpoint to a separate
+ location, outside the main code stream, making any adjustments
+ to the instruction, register, and memory state as directed by
+ T's architecture.
+ n2) We single-step T over the instruction at its new location.
+ n3) We adjust the resulting register and memory state as directed
+ by T's architecture. This includes resetting T's PC to point
+ back into the main instruction stream.
+ n4) We resume T.
+
+ This approach depends on the following gdbarch methods:
+
+ - gdbarch_max_insn_length and gdbarch_displaced_step_location
+ indicate where to copy the instruction, and how much space must
+ be reserved there. We use these in step n1.
+
+ - gdbarch_displaced_step_copy_insn copies a instruction to a new
+ address, and makes any necessary adjustments to the instruction,
+ register contents, and memory. We use this in step n1.
+
+ - gdbarch_displaced_step_fixup adjusts registers and memory after
+ we have successfuly single-stepped the instruction, to yield the
+ same effect the instruction would have had if we had executed it
+ at its original address. We use this in step n3.
+
+ - gdbarch_displaced_step_free_closure provides cleanup.
+
+ The gdbarch_displaced_step_copy_insn and
+ gdbarch_displaced_step_fixup functions must be written so that
+ copying an instruction with gdbarch_displaced_step_copy_insn,
+ single-stepping across the copied instruction, and then applying
+ gdbarch_displaced_insn_fixup should have the same effects on the
+ thread's memory and registers as stepping the instruction in place
+ would have. Exactly which responsibilities fall to the copy and
+ which fall to the fixup is up to the author of those functions.
+
+ See the comments in gdbarch.sh for details.
+
+ Note that displaced stepping and software single-step cannot
+ currently be used in combination, although with some care I think
+ they could be made to. Software single-step works by placing
+ breakpoints on all possible subsequent instructions; if the
+ displaced instruction is a PC-relative jump, those breakpoints
+ could fall in very strange places --- on pages that aren't
+ executable, or at addresses that are not proper instruction
+ boundaries. (We do generally let other threads run while we wait
+ to hit the software single-step breakpoint, and they might
+ encounter such a corrupted instruction.) One way to work around
+ this would be to have gdbarch_displaced_step_copy_insn fully
+ simulate the effect of PC-relative instructions (and return NULL)
+ on architectures that use software single-stepping.
+
+ In non-stop mode, we can have independent and simultaneous step
+ requests, so more than one thread may need to simultaneously step
+ over a breakpoint. The current implementation assumes there is
+ only one scratch space per process. In this case, we have to
+ serialize access to the scratch space. If thread A wants to step
+ over a breakpoint, but we are currently waiting for some other
+ thread to complete a displaced step, we leave thread A stopped and
+ place it in the displaced_step_request_queue. Whenever a displaced
+ step finishes, we pick the next thread in the queue and start a new
+ displaced step operation on it. See displaced_step_prepare and
+ displaced_step_fixup for details. */
+
+/* If this is not null_ptid, this is the thread carrying out a
+ displaced single-step. This thread's state will require fixing up
+ once it has completed its step. */
+static ptid_t displaced_step_ptid;
+
+struct displaced_step_request
+{
+ ptid_t ptid;
+ struct displaced_step_request *next;
+};
+
+/* A queue of pending displaced stepping requests. */
+struct displaced_step_request *displaced_step_request_queue;
+
+/* The architecture the thread had when we stepped it. */
+static struct gdbarch *displaced_step_gdbarch;
+
+/* The closure provided gdbarch_displaced_step_copy_insn, to be used
+ for post-step cleanup. */
+static struct displaced_step_closure *displaced_step_closure;
+
+/* The address of the original instruction, and the copy we made. */
+static CORE_ADDR displaced_step_original, displaced_step_copy;
+
+/* Saved contents of copy area. */
+static gdb_byte *displaced_step_saved_copy;
+
+/* Enum strings for "set|show displaced-stepping". */
+
+static const char can_use_displaced_stepping_auto[] = "auto";
+static const char can_use_displaced_stepping_on[] = "on";
+static const char can_use_displaced_stepping_off[] = "off";
+static const char *can_use_displaced_stepping_enum[] =
+{
+ can_use_displaced_stepping_auto,
+ can_use_displaced_stepping_on,
+ can_use_displaced_stepping_off,
+ NULL,
+};
+
+/* If ON, and the architecture supports it, GDB will use displaced
+ stepping to step over breakpoints. If OFF, or if the architecture
+ doesn't support it, GDB will instead use the traditional
+ hold-and-step approach. If AUTO (which is the default), GDB will
+ decide which technique to use to step over breakpoints depending on
+ which of all-stop or non-stop mode is active --- displaced stepping
+ in non-stop mode; hold-and-step in all-stop mode. */
+
+static const char *can_use_displaced_stepping =
+ can_use_displaced_stepping_auto;
+
+static void
+show_can_use_displaced_stepping (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c,
+ const char *value)
+{
+ if (can_use_displaced_stepping == can_use_displaced_stepping_auto)
+ fprintf_filtered (file, _("\
+Debugger's willingness to use displaced stepping to step over \
+breakpoints is %s (currently %s).\n"),
+ value, non_stop ? "on" : "off");
+ else
+ fprintf_filtered (file, _("\
+Debugger's willingness to use displaced stepping to step over \
+breakpoints is %s.\n"), value);
+}
+
+/* Return non-zero if displaced stepping can/should be used to step
+ over breakpoints. */
+
+static int
+use_displaced_stepping (struct gdbarch *gdbarch)
+{
+ return (((can_use_displaced_stepping == can_use_displaced_stepping_auto
+ && non_stop)
+ || can_use_displaced_stepping == can_use_displaced_stepping_on)
+ && gdbarch_displaced_step_copy_insn_p (gdbarch)
+ && !RECORD_IS_USED);
+}
+
+/* Clean out any stray displaced stepping state. */
+static void
+displaced_step_clear (void)
+{
+ /* Indicate that there is no cleanup pending. */
+ displaced_step_ptid = null_ptid;
+
+ if (displaced_step_closure)
+ {
+ gdbarch_displaced_step_free_closure (displaced_step_gdbarch,
+ displaced_step_closure);
+ displaced_step_closure = NULL;
+ }
+}
+
+static void
+displaced_step_clear_cleanup (void *ignore)
+{
+ displaced_step_clear ();
+}
+
+/* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
+void
+displaced_step_dump_bytes (struct ui_file *file,
+ const gdb_byte *buf,
+ size_t len)
+{
+ int i;
+
+ for (i = 0; i < len; i++)
+ fprintf_unfiltered (file, "%02x ", buf[i]);
+ fputs_unfiltered ("\n", file);
+}
+
+/* Prepare to single-step, using displaced stepping.
+
+ Note that we cannot use displaced stepping when we have a signal to
+ deliver. If we have a signal to deliver and an instruction to step
+ over, then after the step, there will be no indication from the
+ target whether the thread entered a signal handler or ignored the
+ signal and stepped over the instruction successfully --- both cases
+ result in a simple SIGTRAP. In the first case we mustn't do a
+ fixup, and in the second case we must --- but we can't tell which.
+ Comments in the code for 'random signals' in handle_inferior_event
+ explain how we handle this case instead.
+
+ Returns 1 if preparing was successful -- this thread is going to be
+ stepped now; or 0 if displaced stepping this thread got queued. */
+static int
+displaced_step_prepare (ptid_t ptid)
+{
+ struct cleanup *old_cleanups, *ignore_cleanups;
+ struct regcache *regcache = get_thread_regcache (ptid);
+ struct gdbarch *gdbarch = get_regcache_arch (regcache);
+ CORE_ADDR original, copy;
+ ULONGEST len;
+ struct displaced_step_closure *closure;
+
+ /* We should never reach this function if the architecture does not
+ support displaced stepping. */
+ gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch));
+
+ /* For the first cut, we're displaced stepping one thread at a
+ time. */
+
+ if (!ptid_equal (displaced_step_ptid, null_ptid))
+ {
+ /* Already waiting for a displaced step to finish. Defer this
+ request and place in queue. */
+ struct displaced_step_request *req, *new_req;
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog,
+ "displaced: defering step of %s\n",
+ target_pid_to_str (ptid));
+
+ new_req = xmalloc (sizeof (*new_req));
+ new_req->ptid = ptid;
+ new_req->next = NULL;
+
+ if (displaced_step_request_queue)
+ {
+ for (req = displaced_step_request_queue;
+ req && req->next;
+ req = req->next)
+ ;
+ req->next = new_req;
+ }
+ else
+ displaced_step_request_queue = new_req;
+
+ return 0;
+ }
+ else
+ {
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog,
+ "displaced: stepping %s now\n",
+ target_pid_to_str (ptid));
+ }
+
+ displaced_step_clear ();
+
+ old_cleanups = save_inferior_ptid ();
+ inferior_ptid = ptid;
+
+ original = regcache_read_pc (regcache);
+
+ copy = gdbarch_displaced_step_location (gdbarch);
+ len = gdbarch_max_insn_length (gdbarch);
+
+ /* Save the original contents of the copy area. */
+ displaced_step_saved_copy = xmalloc (len);
+ ignore_cleanups = make_cleanup (free_current_contents,
+ &displaced_step_saved_copy);
+ read_memory (copy, displaced_step_saved_copy, len);
+ if (debug_displaced)
+ {
+ fprintf_unfiltered (gdb_stdlog, "displaced: saved 0x%s: ",
+ paddr_nz (copy));
+ displaced_step_dump_bytes (gdb_stdlog, displaced_step_saved_copy, len);
+ };
+
+ closure = gdbarch_displaced_step_copy_insn (gdbarch,
+ original, copy, regcache);
+
+ /* We don't support the fully-simulated case at present. */
+ gdb_assert (closure);
+
+ /* Save the information we need to fix things up if the step
+ succeeds. */
+ displaced_step_ptid = ptid;
+ displaced_step_gdbarch = gdbarch;
+ displaced_step_closure = closure;
+ displaced_step_original = original;
+ displaced_step_copy = copy;
+
+ make_cleanup (displaced_step_clear_cleanup, 0);
+
+ /* Resume execution at the copy. */
+ regcache_write_pc (regcache, copy);
+
+ discard_cleanups (ignore_cleanups);
+
+ do_cleanups (old_cleanups);
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: displaced pc to 0x%s\n",
+ paddr_nz (copy));
+
+ return 1;
+}
+
+static void
+write_memory_ptid (ptid_t ptid, CORE_ADDR memaddr, const gdb_byte *myaddr, int len)
+{
+ struct cleanup *ptid_cleanup = save_inferior_ptid ();
+ inferior_ptid = ptid;
+ write_memory (memaddr, myaddr, len);
+ do_cleanups (ptid_cleanup);
+}
+
+static void
+displaced_step_fixup (ptid_t event_ptid, enum target_signal signal)
+{
+ struct cleanup *old_cleanups;
+
+ /* Was this event for the pid we displaced? */
+ if (ptid_equal (displaced_step_ptid, null_ptid)
+ || ! ptid_equal (displaced_step_ptid, event_ptid))
+ return;
+
+ old_cleanups = make_cleanup (displaced_step_clear_cleanup, 0);
+
+ /* Restore the contents of the copy area. */
+ {
+ ULONGEST len = gdbarch_max_insn_length (displaced_step_gdbarch);
+ write_memory_ptid (displaced_step_ptid, displaced_step_copy,
+ displaced_step_saved_copy, len);
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: restored 0x%s\n",
+ paddr_nz (displaced_step_copy));
+ }
+
+ /* Did the instruction complete successfully? */
+ if (signal == TARGET_SIGNAL_TRAP)
+ {
+ /* Fix up the resulting state. */
+ gdbarch_displaced_step_fixup (displaced_step_gdbarch,
+ displaced_step_closure,
+ displaced_step_original,
+ displaced_step_copy,
+ get_thread_regcache (displaced_step_ptid));
+ }
+ else
+ {
+ /* Since the instruction didn't complete, all we can do is
+ relocate the PC. */
+ struct regcache *regcache = get_thread_regcache (event_ptid);
+ CORE_ADDR pc = regcache_read_pc (regcache);
+ pc = displaced_step_original + (pc - displaced_step_copy);
+ regcache_write_pc (regcache, pc);
+ }
+
+ do_cleanups (old_cleanups);
+
+ displaced_step_ptid = null_ptid;
+
+ /* Are there any pending displaced stepping requests? If so, run
+ one now. */
+ while (displaced_step_request_queue)
+ {
+ struct displaced_step_request *head;
+ ptid_t ptid;
+ CORE_ADDR actual_pc;
+
+ head = displaced_step_request_queue;
+ ptid = head->ptid;
+ displaced_step_request_queue = head->next;
+ xfree (head);
+
+ context_switch (ptid);
+
+ actual_pc = regcache_read_pc (get_thread_regcache (ptid));
+
+ if (breakpoint_here_p (actual_pc))
+ {
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog,
+ "displaced: stepping queued %s now\n",
+ target_pid_to_str (ptid));
+
+ displaced_step_prepare (ptid);
+
+ if (debug_displaced)
+ {
+ gdb_byte buf[4];
+
+ fprintf_unfiltered (gdb_stdlog, "displaced: run 0x%s: ",
+ paddr_nz (actual_pc));
+ read_memory (actual_pc, buf, sizeof (buf));
+ displaced_step_dump_bytes (gdb_stdlog, buf, sizeof (buf));
+ }
+
+ target_resume (ptid, 1, TARGET_SIGNAL_0);
+
+ /* Done, we're stepping a thread. */
+ break;
+ }
+ else
+ {
+ int step;
+ struct thread_info *tp = inferior_thread ();
+
+ /* The breakpoint we were sitting under has since been
+ removed. */
+ tp->trap_expected = 0;
+
+ /* Go back to what we were trying to do. */
+ step = currently_stepping (tp);
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "breakpoint is gone %s: step(%d)\n",
+ target_pid_to_str (tp->ptid), step);
+
+ target_resume (ptid, step, TARGET_SIGNAL_0);
+ tp->stop_signal = TARGET_SIGNAL_0;
+
+ /* This request was discarded. See if there's any other
+ thread waiting for its turn. */
+ }
+ }
+}
+
+/* Update global variables holding ptids to hold NEW_PTID if they were
+ holding OLD_PTID. */
+static void
+infrun_thread_ptid_changed (ptid_t old_ptid, ptid_t new_ptid)
+{
+ struct displaced_step_request *it;
+
+ if (ptid_equal (inferior_ptid, old_ptid))
+ inferior_ptid = new_ptid;
+
+ if (ptid_equal (singlestep_ptid, old_ptid))
+ singlestep_ptid = new_ptid;
+
+ if (ptid_equal (displaced_step_ptid, old_ptid))
+ displaced_step_ptid = new_ptid;
+
+ if (ptid_equal (deferred_step_ptid, old_ptid))
+ deferred_step_ptid = new_ptid;
+
+ for (it = displaced_step_request_queue; it; it = it->next)
+ if (ptid_equal (it->ptid, old_ptid))
+ it->ptid = new_ptid;
+}
+
\f
+/* Resuming. */
/* Things to clean up if we QUIT out of resume (). */
static void
}
}
+/* True if execution commands resume all threads of all processes by
+ default; otherwise, resume only threads of the current inferior
+ process. */
+int sched_multi = 0;
+
+/* Try to setup for software single stepping over the specified location.
+ Return 1 if target_resume() should use hardware single step.
+
+ GDBARCH the current gdbarch.
+ PC the location to step over. */
+
+static int
+maybe_software_singlestep (struct gdbarch *gdbarch, CORE_ADDR pc)
+{
+ int hw_step = 1;
+
+ if (gdbarch_software_single_step_p (gdbarch)
+ && gdbarch_software_single_step (gdbarch, get_current_frame ()))
+ {
+ hw_step = 0;
+ /* Do not pull these breakpoints until after a `wait' in
+ `wait_for_inferior' */
+ singlestep_breakpoints_inserted_p = 1;
+ singlestep_ptid = inferior_ptid;
+ singlestep_pc = pc;
+ }
+ return hw_step;
+}
/* Resume the inferior, but allow a QUIT. This is useful if the user
wants to interrupt some lengthy single-stepping operation
{
int should_resume = 1;
struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
+ struct regcache *regcache = get_current_regcache ();
+ struct gdbarch *gdbarch = get_regcache_arch (regcache);
+ struct thread_info *tp = inferior_thread ();
+ CORE_ADDR pc = regcache_read_pc (regcache);
+
QUIT;
if (debug_infrun)
- fprintf_unfiltered (gdb_stdlog, "infrun: resume (step=%d, signal=%d)\n",
- step, sig);
-
- /* FIXME: calling breakpoint_here_p (read_pc ()) three times! */
-
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: resume (step=%d, signal=%d), "
+ "trap_expected=%d\n",
+ step, sig, tp->trap_expected);
/* Some targets (e.g. Solaris x86) have a kernel bug when stepping
over an instruction that causes a page fault without triggering
Work around the problem by removing hardware watchpoints if a step is
requested, GDB will check for a hardware watchpoint trigger after the
step anyway. */
- if (CANNOT_STEP_HW_WATCHPOINTS && step && breakpoints_inserted)
+ if (CANNOT_STEP_HW_WATCHPOINTS && step)
remove_hw_watchpoints ();
removed or inserted, as appropriate. The exception is if we're sitting
at a permanent breakpoint; we need to step over it, but permanent
breakpoints can't be removed. So we have to test for it here. */
- if (breakpoint_here_p (read_pc ()) == permanent_breakpoint_here)
- SKIP_PERMANENT_BREAKPOINT ();
-
- if (SOFTWARE_SINGLE_STEP_P () && step)
+ if (breakpoint_here_p (pc) == permanent_breakpoint_here)
{
- /* Do it the hard way, w/temp breakpoints */
- SOFTWARE_SINGLE_STEP (sig, 1 /*insert-breakpoints */ );
- /* ...and don't ask hardware to do it. */
- step = 0;
- /* and do not pull these breakpoints until after a `wait' in
- `wait_for_inferior' */
- singlestep_breakpoints_inserted_p = 1;
- singlestep_ptid = inferior_ptid;
+ if (gdbarch_skip_permanent_breakpoint_p (gdbarch))
+ gdbarch_skip_permanent_breakpoint (gdbarch, regcache);
+ else
+ error (_("\
+The program is stopped at a permanent breakpoint, but GDB does not know\n\
+how to step past a permanent breakpoint on this architecture. Try using\n\
+a command like `return' or `jump' to continue execution."));
}
- /* If there were any forks/vforks/execs that were caught and are
- now to be followed, then do so. */
- switch (pending_follow.kind)
+ /* If enabled, step over breakpoints by executing a copy of the
+ instruction at a different address.
+
+ We can't use displaced stepping when we have a signal to deliver;
+ the comments for displaced_step_prepare explain why. The
+ comments in the handle_inferior event for dealing with 'random
+ signals' explain what we do instead. */
+ if (use_displaced_stepping (gdbarch)
+ && tp->trap_expected
+ && sig == TARGET_SIGNAL_0)
{
- case TARGET_WAITKIND_FORKED:
- case TARGET_WAITKIND_VFORKED:
- pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
- if (follow_fork ())
- should_resume = 0;
- break;
+ if (!displaced_step_prepare (inferior_ptid))
+ {
+ /* Got placed in displaced stepping queue. Will be resumed
+ later when all the currently queued displaced stepping
+ requests finish. The thread is not executing at this point,
+ and the call to set_executing will be made later. But we
+ need to call set_running here, since from frontend point of view,
+ the thread is running. */
+ set_running (inferior_ptid, 1);
+ discard_cleanups (old_cleanups);
+ return;
+ }
+ }
- case TARGET_WAITKIND_EXECD:
- /* follow_exec is called as soon as the exec event is seen. */
- pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
- break;
-
- default:
- break;
- }
-
- /* Install inferior's terminal modes. */
- target_terminal_inferior ();
+ /* Do we need to do it the hard way, w/temp breakpoints? */
+ if (step)
+ step = maybe_software_singlestep (gdbarch, pc);
if (should_resume)
{
ptid_t resume_ptid;
- resume_ptid = RESUME_ALL; /* Default */
+ /* If STEP is set, it's a request to use hardware stepping
+ facilities. But in that case, we should never
+ use singlestep breakpoint. */
+ gdb_assert (!(singlestep_breakpoints_inserted_p && step));
- if ((step || singlestep_breakpoints_inserted_p)
- && (stepping_past_singlestep_breakpoint
- || (!breakpoints_inserted && breakpoint_here_p (read_pc ()))))
+ /* Decide the set of threads to ask the target to resume. Start
+ by assuming everything will be resumed, than narrow the set
+ by applying increasingly restricting conditions. */
+
+ /* By default, resume all threads of all processes. */
+ resume_ptid = RESUME_ALL;
+
+ /* Maybe resume only all threads of the current process. */
+ if (!sched_multi && target_supports_multi_process ())
{
- /* Stepping past a breakpoint without inserting breakpoints.
- Make sure only the current thread gets to step, so that
- other threads don't sneak past breakpoints while they are
- not inserted. */
+ resume_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
+ }
+ /* Maybe resume a single thread after all. */
+ if (singlestep_breakpoints_inserted_p
+ && stepping_past_singlestep_breakpoint)
+ {
+ /* The situation here is as follows. In thread T1 we wanted to
+ single-step. Lacking hardware single-stepping we've
+ set breakpoint at the PC of the next instruction -- call it
+ P. After resuming, we've hit that breakpoint in thread T2.
+ Now we've removed original breakpoint, inserted breakpoint
+ at P+1, and try to step to advance T2 past breakpoint.
+ We need to step only T2, as if T1 is allowed to freely run,
+ it can run past P, and if other threads are allowed to run,
+ they can hit breakpoint at P+1, and nested hits of single-step
+ breakpoints is not something we'd want -- that's complicated
+ to support, and has no value. */
resume_ptid = inferior_ptid;
}
-
- if ((scheduler_mode == schedlock_on)
- || (scheduler_mode == schedlock_step
- && (step || singlestep_breakpoints_inserted_p)))
+ else if ((step || singlestep_breakpoints_inserted_p)
+ && tp->trap_expected)
+ {
+ /* We're allowing a thread to run past a breakpoint it has
+ hit, by single-stepping the thread with the breakpoint
+ removed. In which case, we need to single-step only this
+ thread, and keep others stopped, as they can miss this
+ breakpoint if allowed to run.
+
+ The current code actually removes all breakpoints when
+ doing this, not just the one being stepped over, so if we
+ let other threads run, we can actually miss any
+ breakpoint, not just the one at PC. */
+ resume_ptid = inferior_ptid;
+ }
+ else if (non_stop)
+ {
+ /* With non-stop mode on, threads are always handled
+ individually. */
+ resume_ptid = inferior_ptid;
+ }
+ else if ((scheduler_mode == schedlock_on)
+ || (scheduler_mode == schedlock_step
+ && (step || singlestep_breakpoints_inserted_p)))
{
/* User-settable 'scheduler' mode requires solo thread resume. */
resume_ptid = inferior_ptid;
}
- if (CANNOT_STEP_BREAKPOINT)
+ if (gdbarch_cannot_step_breakpoint (gdbarch))
{
/* Most targets can step a breakpoint instruction, thus
executing it normally. But if this one cannot, just
continue and we will hit it anyway. */
- if (step && breakpoints_inserted && breakpoint_here_p (read_pc ()))
+ if (step && breakpoint_inserted_here_p (pc))
step = 0;
}
+
+ if (debug_displaced
+ && use_displaced_stepping (gdbarch)
+ && tp->trap_expected)
+ {
+ struct regcache *resume_regcache = get_thread_regcache (resume_ptid);
+ CORE_ADDR actual_pc = regcache_read_pc (resume_regcache);
+ gdb_byte buf[4];
+
+ fprintf_unfiltered (gdb_stdlog, "displaced: run 0x%s: ",
+ paddr_nz (actual_pc));
+ read_memory (actual_pc, buf, sizeof (buf));
+ displaced_step_dump_bytes (gdb_stdlog, buf, sizeof (buf));
+ }
+
+ /* Install inferior's terminal modes. */
+ target_terminal_inferior ();
+
+ /* Avoid confusing the next resume, if the next stop/resume
+ happens to apply to another thread. */
+ tp->stop_signal = TARGET_SIGNAL_0;
+
target_resume (resume_ptid, step, sig);
}
discard_cleanups (old_cleanups);
}
\f
+/* Proceeding. */
/* Clear out all variables saying what to do when inferior is continued.
First do this, then set the ones you want, then call `proceed'. */
+static void
+clear_proceed_status_thread (struct thread_info *tp)
+{
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: clear_proceed_status_thread (%s)\n",
+ target_pid_to_str (tp->ptid));
+
+ tp->trap_expected = 0;
+ tp->step_range_start = 0;
+ tp->step_range_end = 0;
+ tp->step_frame_id = null_frame_id;
+ tp->step_stack_frame_id = null_frame_id;
+ tp->step_over_calls = STEP_OVER_UNDEBUGGABLE;
+ tp->stop_requested = 0;
+
+ tp->stop_step = 0;
+
+ tp->proceed_to_finish = 0;
+
+ /* Discard any remaining commands or status from previous stop. */
+ bpstat_clear (&tp->stop_bpstat);
+}
+
+static int
+clear_proceed_status_callback (struct thread_info *tp, void *data)
+{
+ if (is_exited (tp->ptid))
+ return 0;
+
+ clear_proceed_status_thread (tp);
+ return 0;
+}
+
void
clear_proceed_status (void)
{
- trap_expected = 0;
- step_range_start = 0;
- step_range_end = 0;
- step_frame_id = null_frame_id;
- step_over_calls = STEP_OVER_UNDEBUGGABLE;
+ if (!ptid_equal (inferior_ptid, null_ptid))
+ {
+ struct inferior *inferior;
+
+ if (non_stop)
+ {
+ /* If in non-stop mode, only delete the per-thread status
+ of the current thread. */
+ clear_proceed_status_thread (inferior_thread ());
+ }
+ else
+ {
+ /* In all-stop mode, delete the per-thread status of
+ *all* threads. */
+ iterate_over_threads (clear_proceed_status_callback, NULL);
+ }
+
+ inferior = current_inferior ();
+ inferior->stop_soon = NO_STOP_QUIETLY;
+ }
+
stop_after_trap = 0;
- stop_soon = NO_STOP_QUIETLY;
- proceed_to_finish = 0;
- breakpoint_proceeded = 1; /* We're about to proceed... */
- /* Discard any remaining commands or status from previous stop. */
- bpstat_clear (&stop_bpstat);
+ observer_notify_about_to_proceed ();
+
+ if (stop_registers)
+ {
+ regcache_xfree (stop_registers);
+ stop_registers = NULL;
+ }
}
-/* This should be suitable for any targets that support threads. */
+/* Check the current thread against the thread that reported the most recent
+ event. If a step-over is required return TRUE and set the current thread
+ to the old thread. Otherwise return FALSE.
+
+ This should be suitable for any targets that support threads. */
static int
-prepare_to_proceed (void)
+prepare_to_proceed (int step)
{
ptid_t wait_ptid;
struct target_waitstatus wait_status;
+ int schedlock_enabled;
+
+ /* With non-stop mode on, threads are always handled individually. */
+ gdb_assert (! non_stop);
/* Get the last target status returned by target_wait(). */
get_last_target_status (&wait_ptid, &wait_status);
- /* Make sure we were stopped either at a breakpoint, or because
- of a Ctrl-C. */
+ /* Make sure we were stopped at a breakpoint. */
if (wait_status.kind != TARGET_WAITKIND_STOPPED
- || (wait_status.value.sig != TARGET_SIGNAL_TRAP
- && wait_status.value.sig != TARGET_SIGNAL_INT))
+ || wait_status.value.sig != TARGET_SIGNAL_TRAP)
{
return 0;
}
+ schedlock_enabled = (scheduler_mode == schedlock_on
+ || (scheduler_mode == schedlock_step
+ && step));
+
+ /* Don't switch over to WAIT_PTID if scheduler locking is on. */
+ if (schedlock_enabled)
+ return 0;
+
+ /* Don't switch over if we're about to resume some other process
+ other than WAIT_PTID's, and schedule-multiple is off. */
+ if (!sched_multi
+ && ptid_get_pid (wait_ptid) != ptid_get_pid (inferior_ptid))
+ return 0;
+
+ /* Switched over from WAIT_PID. */
if (!ptid_equal (wait_ptid, minus_one_ptid)
&& !ptid_equal (inferior_ptid, wait_ptid))
{
- /* Switched over from WAIT_PID. */
- CORE_ADDR wait_pc = read_pc_pid (wait_ptid);
+ struct regcache *regcache = get_thread_regcache (wait_ptid);
- if (wait_pc != read_pc ())
+ if (breakpoint_here_p (regcache_read_pc (regcache)))
{
+ /* If stepping, remember current thread to switch back to. */
+ if (step)
+ deferred_step_ptid = inferior_ptid;
+
/* Switch back to WAIT_PID thread. */
- inferior_ptid = wait_ptid;
+ switch_to_thread (wait_ptid);
- /* FIXME: This stuff came from switch_to_thread() in
- thread.c (which should probably be a public function). */
- flush_cached_frames ();
- registers_changed ();
- stop_pc = wait_pc;
- select_frame (get_current_frame ());
+ /* We return 1 to indicate that there is a breakpoint here,
+ so we need to step over it before continuing to avoid
+ hitting it straight away. */
+ return 1;
}
-
- /* We return 1 to indicate that there is a breakpoint here,
- so we need to step over it before continuing to avoid
- hitting it straight away. */
- if (breakpoint_here_p (wait_pc))
- return 1;
}
return 0;
-
}
-/* Record the pc of the program the last time it stopped. This is
- just used internally by wait_for_inferior, but need to be preserved
- over calls to it and cleared when the inferior is started. */
-static CORE_ADDR prev_pc;
-
/* Basic routine for continuing the program in various fashions.
ADDR is the address to resume at, or -1 for resume where stopped.
void
proceed (CORE_ADDR addr, enum target_signal siggnal, int step)
{
+ struct regcache *regcache;
+ struct gdbarch *gdbarch;
+ struct thread_info *tp;
+ CORE_ADDR pc;
int oneproc = 0;
+ /* If we're stopped at a fork/vfork, follow the branch set by the
+ "set follow-fork-mode" command; otherwise, we'll just proceed
+ resuming the current thread. */
+ if (!follow_fork ())
+ {
+ /* The target for some reason decided not to resume. */
+ normal_stop ();
+ return;
+ }
+
+ regcache = get_current_regcache ();
+ gdbarch = get_regcache_arch (regcache);
+ pc = regcache_read_pc (regcache);
+
if (step > 0)
- step_start_function = find_pc_function (read_pc ());
+ step_start_function = find_pc_function (pc);
if (step < 0)
stop_after_trap = 1;
if (addr == (CORE_ADDR) -1)
{
- if (read_pc () == stop_pc && breakpoint_here_p (read_pc ()))
+ if (pc == stop_pc && breakpoint_here_p (pc)
+ && execution_direction != EXEC_REVERSE)
/* There is a breakpoint at the address we will resume at,
step one instruction before inserting breakpoints so that
we do not stop right away (and report a second hit at this
- breakpoint). */
+ breakpoint).
+
+ Note, we don't do this in reverse, because we won't
+ actually be executing the breakpoint insn anyway.
+ We'll be (un-)executing the previous instruction. */
+
oneproc = 1;
- else if (gdbarch_single_step_through_delay_p (current_gdbarch)
- && gdbarch_single_step_through_delay (current_gdbarch,
- get_current_frame ()))
+ else if (gdbarch_single_step_through_delay_p (gdbarch)
+ && gdbarch_single_step_through_delay (gdbarch,
+ get_current_frame ()))
/* We stepped onto an instruction that needs to be stepped
again before re-inserting the breakpoint, do so. */
oneproc = 1;
}
else
{
- write_pc (addr);
+ regcache_write_pc (regcache, addr);
}
if (debug_infrun)
"infrun: proceed (addr=0x%s, signal=%d, step=%d)\n",
paddr_nz (addr), siggnal, step);
- /* In a multi-threaded task we may select another thread
- and then continue or step.
-
- But if the old thread was stopped at a breakpoint, it
- will immediately cause another breakpoint stop without
- any execution (i.e. it will report a breakpoint hit
- incorrectly). So we must step over it first.
+ if (non_stop)
+ /* In non-stop, each thread is handled individually. The context
+ must already be set to the right thread here. */
+ ;
+ else
+ {
+ /* In a multi-threaded task we may select another thread and
+ then continue or step.
+
+ But if the old thread was stopped at a breakpoint, it will
+ immediately cause another breakpoint stop without any
+ execution (i.e. it will report a breakpoint hit incorrectly).
+ So we must step over it first.
+
+ prepare_to_proceed checks the current thread against the
+ thread that reported the most recent event. If a step-over
+ is required it returns TRUE and sets the current thread to
+ the old thread. */
+ if (prepare_to_proceed (step))
+ oneproc = 1;
+ }
- prepare_to_proceed checks the current thread against the thread
- that reported the most recent event. If a step-over is required
- it returns TRUE and sets the current thread to the old thread. */
- if (prepare_to_proceed () && breakpoint_here_p (read_pc ()))
- oneproc = 1;
+ /* prepare_to_proceed may change the current thread. */
+ tp = inferior_thread ();
if (oneproc)
- /* We will get a trace trap after one instruction.
- Continue it automatically and insert breakpoints then. */
- trap_expected = 1;
- else
{
- insert_breakpoints ();
- /* If we get here there was no call to error() in
- insert breakpoints -- so they were inserted. */
- breakpoints_inserted = 1;
+ tp->trap_expected = 1;
+ /* If displaced stepping is enabled, we can step over the
+ breakpoint without hitting it, so leave all breakpoints
+ inserted. Otherwise we need to disable all breakpoints, step
+ one instruction, and then re-add them when that step is
+ finished. */
+ if (!use_displaced_stepping (gdbarch))
+ remove_breakpoints ();
+ }
+
+ /* We can insert breakpoints if we're not trying to step over one,
+ or if we are stepping over one but we're using displaced stepping
+ to do so. */
+ if (! tp->trap_expected || use_displaced_stepping (gdbarch))
+ insert_breakpoints ();
+
+ if (!non_stop)
+ {
+ /* Pass the last stop signal to the thread we're resuming,
+ irrespective of whether the current thread is the thread that
+ got the last event or not. This was historically GDB's
+ behaviour before keeping a stop_signal per thread. */
+
+ struct thread_info *last_thread;
+ ptid_t last_ptid;
+ struct target_waitstatus last_status;
+
+ get_last_target_status (&last_ptid, &last_status);
+ if (!ptid_equal (inferior_ptid, last_ptid)
+ && !ptid_equal (last_ptid, null_ptid)
+ && !ptid_equal (last_ptid, minus_one_ptid))
+ {
+ last_thread = find_thread_ptid (last_ptid);
+ if (last_thread)
+ {
+ tp->stop_signal = last_thread->stop_signal;
+ last_thread->stop_signal = TARGET_SIGNAL_0;
+ }
+ }
}
if (siggnal != TARGET_SIGNAL_DEFAULT)
- stop_signal = siggnal;
+ tp->stop_signal = siggnal;
/* If this signal should not be seen by program,
give it zero. Used for debugging signals. */
- else if (!signal_program[stop_signal])
- stop_signal = TARGET_SIGNAL_0;
+ else if (!signal_program[tp->stop_signal])
+ tp->stop_signal = TARGET_SIGNAL_0;
annotate_starting ();
the prev_pc value before calculating the line number. This approach
did not work because on platforms that use ptrace, the pc register
cannot be read unless the inferior is stopped. At that point, we
- are not guaranteed the inferior is stopped and so the read_pc ()
+ are not guaranteed the inferior is stopped and so the regcache_read_pc ()
call can fail. Setting the prev_pc value here ensures the value is
updated correctly when the inferior is stopped. */
- prev_pc = read_pc ();
+ tp->prev_pc = regcache_read_pc (get_current_regcache ());
+
+ /* Fill in with reasonable starting values. */
+ init_thread_stepping_state (tp);
+
+ /* Reset to normal state. */
+ init_infwait_state ();
/* Resume inferior. */
- resume (oneproc || step || bpstat_should_step (), stop_signal);
+ resume (oneproc || step || bpstat_should_step (), tp->stop_signal);
/* Wait for it to stop (if not standalone)
and in any case decode why it stopped, and act accordingly. */
does not support asynchronous execution. */
if (!target_can_async_p ())
{
- wait_for_inferior ();
+ wait_for_inferior (0);
normal_stop ();
}
}
void
start_remote (int from_tty)
{
- init_thread_list ();
+ struct inferior *inferior;
init_wait_for_inferior ();
- stop_soon = STOP_QUIETLY;
- trap_expected = 0;
+
+ inferior = current_inferior ();
+ inferior->stop_soon = STOP_QUIETLY_REMOTE;
/* Always go on waiting for the target, regardless of the mode. */
/* FIXME: cagney/1999-09-23: At present it isn't possible to
target_open() return to the caller an indication that the target
is currently running and GDB state should be set to the same as
for an async run. */
- wait_for_inferior ();
+ wait_for_inferior (0);
/* Now that the inferior has stopped, do any bookkeeping like
loading shared libraries. We want to do this before normal_stop,
init_wait_for_inferior (void)
{
/* These are meaningless until the first time through wait_for_inferior. */
- prev_pc = 0;
- breakpoints_inserted = 0;
breakpoint_init_inferior (inf_starting);
- /* Don't confuse first call to proceed(). */
- stop_signal = TARGET_SIGNAL_0;
-
- /* The first resume is not following a fork/vfork/exec. */
- pending_follow.kind = TARGET_WAITKIND_SPURIOUS; /* I.e., none. */
-
clear_proceed_status ();
stepping_past_singlestep_breakpoint = 0;
+ deferred_step_ptid = null_ptid;
+
+ target_last_wait_ptid = minus_one_ptid;
+
+ previous_inferior_ptid = null_ptid;
+ init_infwait_state ();
+
+ displaced_step_clear ();
+
+ /* Discard any skipped inlined frames. */
+ clear_inline_frame_state (minus_one_ptid);
}
+
\f
/* This enum encodes possible reasons for doing a target_wait, so that
wfi can call target_wait in one place. (Ultimately the call will be
{
infwait_normal_state,
infwait_thread_hop_state,
+ infwait_step_watch_state,
infwait_nonstep_watch_state
};
to the interface from within handle_inferior_event(). */
enum inferior_stop_reason
{
- /* We don't know why. */
- STOP_UNKNOWN,
/* Step, next, nexti, stepi finished. */
END_STEPPING_RANGE,
- /* Found breakpoint. */
- BREAKPOINT_HIT,
/* Inferior terminated by signal. */
SIGNAL_EXITED,
/* Inferior exited. */
EXITED,
/* Inferior received signal, and user asked to be notified. */
- SIGNAL_RECEIVED
+ SIGNAL_RECEIVED,
+ /* Reverse execution -- target ran out of history info. */
+ NO_HISTORY
};
-/* This structure contains what used to be local variables in
- wait_for_inferior. Probably many of them can return to being
- locals in handle_inferior_event. */
+/* The PTID we'll do a target_wait on.*/
+ptid_t waiton_ptid;
+
+/* Current inferior wait state. */
+enum infwait_states infwait_state;
+/* Data to be passed around while handling an event. This data is
+ discarded between events. */
struct execution_control_state
{
+ ptid_t ptid;
+ /* The thread that got the event, if this was a thread event; NULL
+ otherwise. */
+ struct thread_info *event_thread;
+
struct target_waitstatus ws;
- struct target_waitstatus *wp;
- int another_trap;
int random_signal;
CORE_ADDR stop_func_start;
CORE_ADDR stop_func_end;
char *stop_func_name;
- struct symtab_and_line sal;
- int current_line;
- struct symtab *current_symtab;
- int handling_longjmp; /* FIXME */
- ptid_t ptid;
- ptid_t saved_inferior_ptid;
- int step_after_step_resume_breakpoint;
- int stepping_through_solib_after_catch;
- bpstat stepping_through_solib_catchpoints;
int new_thread_event;
- struct target_waitstatus tmpstatus;
- enum infwait_states infwait_state;
- ptid_t waiton_ptid;
int wait_some_more;
};
-void init_execution_control_state (struct execution_control_state *ecs);
+static void init_execution_control_state (struct execution_control_state *ecs);
void handle_inferior_event (struct execution_control_state *ecs);
-static void step_into_function (struct execution_control_state *ecs);
+static void handle_step_into_function (struct gdbarch *gdbarch,
+ struct execution_control_state *ecs);
+static void handle_step_into_function_backward (struct gdbarch *gdbarch,
+ struct execution_control_state *ecs);
static void insert_step_resume_breakpoint_at_frame (struct frame_info *step_frame);
static void insert_step_resume_breakpoint_at_caller (struct frame_info *);
static void insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal,
struct frame_id sr_id);
+static void insert_longjmp_resume_breakpoint (CORE_ADDR);
+
static void stop_stepping (struct execution_control_state *ecs);
static void prepare_to_wait (struct execution_control_state *ecs);
static void keep_going (struct execution_control_state *ecs);
static void print_stop_reason (enum inferior_stop_reason stop_reason,
int stop_info);
+/* Callback for iterate over threads. If the thread is stopped, but
+ the user/frontend doesn't know about that yet, go through
+ normal_stop, as if the thread had just stopped now. ARG points at
+ a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
+ ptid_is_pid(PTID) is true, applies to all threads of the process
+ pointed at by PTID. Otherwise, apply only to the thread pointed by
+ PTID. */
+
+static int
+infrun_thread_stop_requested_callback (struct thread_info *info, void *arg)
+{
+ ptid_t ptid = * (ptid_t *) arg;
+
+ if ((ptid_equal (info->ptid, ptid)
+ || ptid_equal (minus_one_ptid, ptid)
+ || (ptid_is_pid (ptid)
+ && ptid_get_pid (ptid) == ptid_get_pid (info->ptid)))
+ && is_running (info->ptid)
+ && !is_executing (info->ptid))
+ {
+ struct cleanup *old_chain;
+ struct execution_control_state ecss;
+ struct execution_control_state *ecs = &ecss;
+
+ memset (ecs, 0, sizeof (*ecs));
+
+ old_chain = make_cleanup_restore_current_thread ();
+
+ switch_to_thread (info->ptid);
+
+ /* Go through handle_inferior_event/normal_stop, so we always
+ have consistent output as if the stop event had been
+ reported. */
+ ecs->ptid = info->ptid;
+ ecs->event_thread = find_thread_ptid (info->ptid);
+ ecs->ws.kind = TARGET_WAITKIND_STOPPED;
+ ecs->ws.value.sig = TARGET_SIGNAL_0;
+
+ handle_inferior_event (ecs);
+
+ if (!ecs->wait_some_more)
+ {
+ struct thread_info *tp;
+
+ normal_stop ();
+
+ /* Finish off the continuations. The continations
+ themselves are responsible for realising the thread
+ didn't finish what it was supposed to do. */
+ tp = inferior_thread ();
+ do_all_intermediate_continuations_thread (tp);
+ do_all_continuations_thread (tp);
+ }
+
+ do_cleanups (old_chain);
+ }
+
+ return 0;
+}
+
+/* This function is attached as a "thread_stop_requested" observer.
+ Cleanup local state that assumed the PTID was to be resumed, and
+ report the stop to the frontend. */
+
+static void
+infrun_thread_stop_requested (ptid_t ptid)
+{
+ struct displaced_step_request *it, *next, *prev = NULL;
+
+ /* PTID was requested to stop. Remove it from the displaced
+ stepping queue, so we don't try to resume it automatically. */
+ for (it = displaced_step_request_queue; it; it = next)
+ {
+ next = it->next;
+
+ if (ptid_equal (it->ptid, ptid)
+ || ptid_equal (minus_one_ptid, ptid)
+ || (ptid_is_pid (ptid)
+ && ptid_get_pid (ptid) == ptid_get_pid (it->ptid)))
+ {
+ if (displaced_step_request_queue == it)
+ displaced_step_request_queue = it->next;
+ else
+ prev->next = it->next;
+
+ xfree (it);
+ }
+ else
+ prev = it;
+ }
+
+ iterate_over_threads (infrun_thread_stop_requested_callback, &ptid);
+}
+
+static void
+infrun_thread_thread_exit (struct thread_info *tp, int silent)
+{
+ if (ptid_equal (target_last_wait_ptid, tp->ptid))
+ nullify_last_target_wait_ptid ();
+}
+
+/* Callback for iterate_over_threads. */
+
+static int
+delete_step_resume_breakpoint_callback (struct thread_info *info, void *data)
+{
+ if (is_exited (info->ptid))
+ return 0;
+
+ delete_step_resume_breakpoint (info);
+ return 0;
+}
+
+/* In all-stop, delete the step resume breakpoint of any thread that
+ had one. In non-stop, delete the step resume breakpoint of the
+ thread that just stopped. */
+
+static void
+delete_step_thread_step_resume_breakpoint (void)
+{
+ if (!target_has_execution
+ || ptid_equal (inferior_ptid, null_ptid))
+ /* If the inferior has exited, we have already deleted the step
+ resume breakpoints out of GDB's lists. */
+ return;
+
+ if (non_stop)
+ {
+ /* If in non-stop mode, only delete the step-resume or
+ longjmp-resume breakpoint of the thread that just stopped
+ stepping. */
+ struct thread_info *tp = inferior_thread ();
+ delete_step_resume_breakpoint (tp);
+ }
+ else
+ /* In all-stop mode, delete all step-resume and longjmp-resume
+ breakpoints of any thread that had them. */
+ iterate_over_threads (delete_step_resume_breakpoint_callback, NULL);
+}
+
+/* A cleanup wrapper. */
+
+static void
+delete_step_thread_step_resume_breakpoint_cleanup (void *arg)
+{
+ delete_step_thread_step_resume_breakpoint ();
+}
+
+/* Pretty print the results of target_wait, for debugging purposes. */
+
+static void
+print_target_wait_results (ptid_t waiton_ptid, ptid_t result_ptid,
+ const struct target_waitstatus *ws)
+{
+ char *status_string = target_waitstatus_to_string (ws);
+ struct ui_file *tmp_stream = mem_fileopen ();
+ char *text;
+ long len;
+
+ /* The text is split over several lines because it was getting too long.
+ Call fprintf_unfiltered (gdb_stdlog) once so that the text is still
+ output as a unit; we want only one timestamp printed if debug_timestamp
+ is set. */
+
+ fprintf_unfiltered (tmp_stream,
+ "infrun: target_wait (%d", PIDGET (waiton_ptid));
+ if (PIDGET (waiton_ptid) != -1)
+ fprintf_unfiltered (tmp_stream,
+ " [%s]", target_pid_to_str (waiton_ptid));
+ fprintf_unfiltered (tmp_stream, ", status) =\n");
+ fprintf_unfiltered (tmp_stream,
+ "infrun: %d [%s],\n",
+ PIDGET (result_ptid), target_pid_to_str (result_ptid));
+ fprintf_unfiltered (tmp_stream,
+ "infrun: %s\n",
+ status_string);
+
+ text = ui_file_xstrdup (tmp_stream, &len);
+
+ /* This uses %s in part to handle %'s in the text, but also to avoid
+ a gcc error: the format attribute requires a string literal. */
+ fprintf_unfiltered (gdb_stdlog, "%s", text);
+
+ xfree (status_string);
+ xfree (text);
+ ui_file_delete (tmp_stream);
+}
+
/* Wait for control to return from inferior to debugger.
+
+ If TREAT_EXEC_AS_SIGTRAP is non-zero, then handle EXEC signals
+ as if they were SIGTRAP signals. This can be useful during
+ the startup sequence on some targets such as HP/UX, where
+ we receive an EXEC event instead of the expected SIGTRAP.
+
If inferior gets a signal, we may decide to start it up again
instead of returning. That is why there is a loop in this function.
When this function actually returns it means the inferior
should be left stopped and GDB should read more commands. */
void
-wait_for_inferior (void)
+wait_for_inferior (int treat_exec_as_sigtrap)
{
struct cleanup *old_cleanups;
struct execution_control_state ecss;
struct execution_control_state *ecs;
if (debug_infrun)
- fprintf_unfiltered (gdb_stdlog, "infrun: wait_for_inferior\n");
+ fprintf_unfiltered
+ (gdb_stdlog, "infrun: wait_for_inferior (treat_exec_as_sigtrap=%d)\n",
+ treat_exec_as_sigtrap);
- old_cleanups = make_cleanup (delete_step_resume_breakpoint,
- &step_resume_breakpoint);
+ old_cleanups =
+ make_cleanup (delete_step_thread_step_resume_breakpoint_cleanup, NULL);
- /* wfi still stays in a loop, so it's OK just to take the address of
- a local to get the ecs pointer. */
ecs = &ecss;
+ memset (ecs, 0, sizeof (*ecs));
- /* Fill in with reasonable starting values. */
- init_execution_control_state (ecs);
+ overlay_cache_invalid = 1;
- /* We'll update this if & when we switch to a new thread. */
+ /* We'll update this if & when we switch to a new thread. */
previous_inferior_ptid = inferior_ptid;
- overlay_cache_invalid = 1;
-
/* We have to invalidate the registers BEFORE calling target_wait
because they can be loaded from the target while in target_wait.
This makes remote debugging a bit more efficient for those
while (1)
{
+ struct cleanup *old_chain;
+
if (deprecated_target_wait_hook)
- ecs->ptid = deprecated_target_wait_hook (ecs->waiton_ptid, ecs->wp);
+ ecs->ptid = deprecated_target_wait_hook (waiton_ptid, &ecs->ws, 0);
else
- ecs->ptid = target_wait (ecs->waiton_ptid, ecs->wp);
+ ecs->ptid = target_wait (waiton_ptid, &ecs->ws, 0);
+
+ if (debug_infrun)
+ print_target_wait_results (waiton_ptid, ecs->ptid, &ecs->ws);
+
+ if (treat_exec_as_sigtrap && ecs->ws.kind == TARGET_WAITKIND_EXECD)
+ {
+ xfree (ecs->ws.value.execd_pathname);
+ ecs->ws.kind = TARGET_WAITKIND_STOPPED;
+ ecs->ws.value.sig = TARGET_SIGNAL_TRAP;
+ }
+
+ /* If an error happens while handling the event, propagate GDB's
+ knowledge of the executing state to the frontend/user running
+ state. */
+ old_chain = make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
/* Now figure out what to do with the result of the result. */
handle_inferior_event (ecs);
+ /* No error, don't finish the state yet. */
+ discard_cleanups (old_chain);
+
if (!ecs->wait_some_more)
break;
}
+
do_cleanups (old_cleanups);
}
event loop whenever a change of state is detected on the file
descriptor corresponding to the target. It can be called more than
once to complete a single execution command. In such cases we need
- to keep the state in a global variable ASYNC_ECSS. If it is the
- last time that this function is called for a single execution
- command, then report to the user that the inferior has stopped, and
- do the necessary cleanups. */
-
-struct execution_control_state async_ecss;
-struct execution_control_state *async_ecs;
+ to keep the state in a global variable ECSS. If it is the last time
+ that this function is called for a single execution command, then
+ report to the user that the inferior has stopped, and do the
+ necessary cleanups. */
void
fetch_inferior_event (void *client_data)
{
- static struct cleanup *old_cleanups;
-
- async_ecs = &async_ecss;
+ struct execution_control_state ecss;
+ struct execution_control_state *ecs = &ecss;
+ struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
+ struct cleanup *ts_old_chain;
+ int was_sync = sync_execution;
- if (!async_ecs->wait_some_more)
- {
- old_cleanups = make_exec_cleanup (delete_step_resume_breakpoint,
- &step_resume_breakpoint);
+ memset (ecs, 0, sizeof (*ecs));
- /* Fill in with reasonable starting values. */
- init_execution_control_state (async_ecs);
+ overlay_cache_invalid = 1;
- /* We'll update this if & when we switch to a new thread. */
- previous_inferior_ptid = inferior_ptid;
+ /* We can only rely on wait_for_more being correct before handling
+ the event in all-stop, but previous_inferior_ptid isn't used in
+ non-stop. */
+ if (!ecs->wait_some_more)
+ /* We'll update this if & when we switch to a new thread. */
+ previous_inferior_ptid = inferior_ptid;
- overlay_cache_invalid = 1;
+ if (non_stop)
+ /* In non-stop mode, the user/frontend should not notice a thread
+ switch due to internal events. Make sure we reverse to the
+ user selected thread and frame after handling the event and
+ running any breakpoint commands. */
+ make_cleanup_restore_current_thread ();
- /* We have to invalidate the registers BEFORE calling target_wait
- because they can be loaded from the target while in target_wait.
- This makes remote debugging a bit more efficient for those
- targets that provide critical registers as part of their normal
- status mechanism. */
+ /* We have to invalidate the registers BEFORE calling target_wait
+ because they can be loaded from the target while in target_wait.
+ This makes remote debugging a bit more efficient for those
+ targets that provide critical registers as part of their normal
+ status mechanism. */
- registers_changed ();
- }
+ registers_changed ();
if (deprecated_target_wait_hook)
- async_ecs->ptid =
- deprecated_target_wait_hook (async_ecs->waiton_ptid, async_ecs->wp);
+ ecs->ptid =
+ deprecated_target_wait_hook (waiton_ptid, &ecs->ws, TARGET_WNOHANG);
else
- async_ecs->ptid = target_wait (async_ecs->waiton_ptid, async_ecs->wp);
+ ecs->ptid = target_wait (waiton_ptid, &ecs->ws, TARGET_WNOHANG);
+
+ if (debug_infrun)
+ print_target_wait_results (waiton_ptid, ecs->ptid, &ecs->ws);
+
+ if (non_stop
+ && ecs->ws.kind != TARGET_WAITKIND_IGNORE
+ && ecs->ws.kind != TARGET_WAITKIND_EXITED
+ && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED)
+ /* In non-stop mode, each thread is handled individually. Switch
+ early, so the global state is set correctly for this
+ thread. */
+ context_switch (ecs->ptid);
+
+ /* If an error happens while handling the event, propagate GDB's
+ knowledge of the executing state to the frontend/user running
+ state. */
+ if (!non_stop)
+ ts_old_chain = make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
+ else
+ ts_old_chain = make_cleanup (finish_thread_state_cleanup, &ecs->ptid);
/* Now figure out what to do with the result of the result. */
- handle_inferior_event (async_ecs);
+ handle_inferior_event (ecs);
- if (!async_ecs->wait_some_more)
+ if (!ecs->wait_some_more)
{
- /* Do only the cleanups that have been added by this
- function. Let the continuations for the commands do the rest,
- if there are any. */
- do_exec_cleanups (old_cleanups);
- normal_stop ();
- if (step_multi && stop_step)
+ struct inferior *inf = find_inferior_pid (ptid_get_pid (ecs->ptid));
+
+ delete_step_thread_step_resume_breakpoint ();
+
+ /* We may not find an inferior if this was a process exit. */
+ if (inf == NULL || inf->stop_soon == NO_STOP_QUIETLY)
+ normal_stop ();
+
+ if (target_has_execution
+ && ecs->ws.kind != TARGET_WAITKIND_EXITED
+ && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED
+ && ecs->event_thread->step_multi
+ && ecs->event_thread->stop_step)
inferior_event_handler (INF_EXEC_CONTINUE, NULL);
else
inferior_event_handler (INF_EXEC_COMPLETE, NULL);
}
+
+ /* No error, don't finish the thread states yet. */
+ discard_cleanups (ts_old_chain);
+
+ /* Revert thread and frame. */
+ do_cleanups (old_chain);
+
+ /* If the inferior was in sync execution mode, and now isn't,
+ restore the prompt. */
+ if (was_sync && !sync_execution)
+ display_gdb_prompt (0);
+}
+
+/* Record the frame and location we're currently stepping through. */
+void
+set_step_info (struct frame_info *frame, struct symtab_and_line sal)
+{
+ struct thread_info *tp = inferior_thread ();
+
+ tp->step_frame_id = get_frame_id (frame);
+ tp->step_stack_frame_id = get_stack_frame_id (frame);
+
+ tp->current_symtab = sal.symtab;
+ tp->current_line = sal.line;
}
/* Prepare an execution control state for looping through a
wait_for_inferior-type loop. */
-void
+static void
init_execution_control_state (struct execution_control_state *ecs)
{
- ecs->another_trap = 0;
ecs->random_signal = 0;
- ecs->step_after_step_resume_breakpoint = 0;
- ecs->handling_longjmp = 0; /* FIXME */
- ecs->stepping_through_solib_after_catch = 0;
- ecs->stepping_through_solib_catchpoints = NULL;
- ecs->sal = find_pc_line (prev_pc, 0);
- ecs->current_line = ecs->sal.line;
- ecs->current_symtab = ecs->sal.symtab;
- ecs->infwait_state = infwait_normal_state;
- ecs->waiton_ptid = pid_to_ptid (-1);
- ecs->wp = &(ecs->ws);
+}
+
+/* Clear context switchable stepping state. */
+
+void
+init_thread_stepping_state (struct thread_info *tss)
+{
+ tss->stepping_over_breakpoint = 0;
+ tss->step_after_step_resume_breakpoint = 0;
+ tss->stepping_through_solib_after_catch = 0;
+ tss->stepping_through_solib_catchpoints = NULL;
}
/* Return the cached copy of the last pid/waitstatus returned by
target_last_wait_ptid = minus_one_ptid;
}
-/* Switch thread contexts, maintaining "infrun state". */
+/* Switch thread contexts. */
static void
-context_switch (struct execution_control_state *ecs)
-{
- /* Caution: it may happen that the new thread (or the old one!)
- is not in the thread list. In this case we must not attempt
- to "switch context", or we run the risk that our context may
- be lost. This may happen as a result of the target module
- mishandling thread creation. */
-
- if (in_thread_list (inferior_ptid) && in_thread_list (ecs->ptid))
- { /* Perform infrun state context switch: */
- /* Save infrun state for the old thread. */
- save_infrun_state (inferior_ptid, prev_pc,
- trap_expected, step_resume_breakpoint,
- step_range_start,
- step_range_end, &step_frame_id,
- ecs->handling_longjmp, ecs->another_trap,
- ecs->stepping_through_solib_after_catch,
- ecs->stepping_through_solib_catchpoints,
- ecs->current_line, ecs->current_symtab);
-
- /* Load infrun state for the new thread. */
- load_infrun_state (ecs->ptid, &prev_pc,
- &trap_expected, &step_resume_breakpoint,
- &step_range_start,
- &step_range_end, &step_frame_id,
- &ecs->handling_longjmp, &ecs->another_trap,
- &ecs->stepping_through_solib_after_catch,
- &ecs->stepping_through_solib_catchpoints,
- &ecs->current_line, &ecs->current_symtab);
- }
- inferior_ptid = ecs->ptid;
+context_switch (ptid_t ptid)
+{
+ if (debug_infrun)
+ {
+ fprintf_unfiltered (gdb_stdlog, "infrun: Switching context from %s ",
+ target_pid_to_str (inferior_ptid));
+ fprintf_unfiltered (gdb_stdlog, "to %s\n",
+ target_pid_to_str (ptid));
+ }
+
+ switch_to_thread (ptid);
}
static void
adjust_pc_after_break (struct execution_control_state *ecs)
{
+ struct regcache *regcache;
+ struct gdbarch *gdbarch;
CORE_ADDR breakpoint_pc;
- /* If this target does not decrement the PC after breakpoints, then
- we have nothing to do. */
- if (DECR_PC_AFTER_BREAK == 0)
- return;
-
/* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
we aren't, just return.
We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
- affected by DECR_PC_AFTER_BREAK. Other waitkinds which are implemented
- by software breakpoints should be handled through the normal breakpoint
- layer.
+ affected by gdbarch_decr_pc_after_break. Other waitkinds which are
+ implemented by software breakpoints should be handled through the normal
+ breakpoint layer.
NOTE drow/2004-01-31: On some targets, breakpoints may generate
different signals (SIGILL or SIGEMT for instance), but it is less
clear where the PC is pointing afterwards. It may not match
- DECR_PC_AFTER_BREAK. I don't know any specific target that generates
- these signals at breakpoints (the code has been in GDB since at least
- 1992) so I can not guess how to handle them here.
+ gdbarch_decr_pc_after_break. I don't know any specific target that
+ generates these signals at breakpoints (the code has been in GDB since at
+ least 1992) so I can not guess how to handle them here.
- In earlier versions of GDB, a target with HAVE_NONSTEPPABLE_WATCHPOINTS
- would have the PC after hitting a watchpoint affected by
- DECR_PC_AFTER_BREAK. I haven't found any target with both of these set
- in GDB history, and it seems unlikely to be correct, so
- HAVE_NONSTEPPABLE_WATCHPOINTS is not checked here. */
+ In earlier versions of GDB, a target with
+ gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
+ watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
+ target with both of these set in GDB history, and it seems unlikely to be
+ correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
if (ecs->ws.kind != TARGET_WAITKIND_STOPPED)
return;
if (ecs->ws.value.sig != TARGET_SIGNAL_TRAP)
return;
+ /* In reverse execution, when a breakpoint is hit, the instruction
+ under it has already been de-executed. The reported PC always
+ points at the breakpoint address, so adjusting it further would
+ be wrong. E.g., consider this case on a decr_pc_after_break == 1
+ architecture:
+
+ B1 0x08000000 : INSN1
+ B2 0x08000001 : INSN2
+ 0x08000002 : INSN3
+ PC -> 0x08000003 : INSN4
+
+ Say you're stopped at 0x08000003 as above. Reverse continuing
+ from that point should hit B2 as below. Reading the PC when the
+ SIGTRAP is reported should read 0x08000001 and INSN2 should have
+ been de-executed already.
+
+ B1 0x08000000 : INSN1
+ B2 PC -> 0x08000001 : INSN2
+ 0x08000002 : INSN3
+ 0x08000003 : INSN4
+
+ We can't apply the same logic as for forward execution, because
+ we would wrongly adjust the PC to 0x08000000, since there's a
+ breakpoint at PC - 1. We'd then report a hit on B1, although
+ INSN1 hadn't been de-executed yet. Doing nothing is the correct
+ behaviour. */
+ if (execution_direction == EXEC_REVERSE)
+ return;
+
+ /* If this target does not decrement the PC after breakpoints, then
+ we have nothing to do. */
+ regcache = get_thread_regcache (ecs->ptid);
+ gdbarch = get_regcache_arch (regcache);
+ if (gdbarch_decr_pc_after_break (gdbarch) == 0)
+ return;
+
/* Find the location where (if we've hit a breakpoint) the
breakpoint would be. */
- breakpoint_pc = read_pc_pid (ecs->ptid) - DECR_PC_AFTER_BREAK;
-
- if (SOFTWARE_SINGLE_STEP_P ())
- {
- /* When using software single-step, a SIGTRAP can only indicate
- an inserted breakpoint. This actually makes things
- easier. */
- if (singlestep_breakpoints_inserted_p)
- /* When software single stepping, the instruction at [prev_pc]
- is never a breakpoint, but the instruction following
- [prev_pc] (in program execution order) always is. Assume
- that following instruction was reached and hence a software
- breakpoint was hit. */
- write_pc_pid (breakpoint_pc, ecs->ptid);
- else if (software_breakpoint_inserted_here_p (breakpoint_pc))
- /* The inferior was free running (i.e., no single-step
- breakpoints inserted) and it hit a software breakpoint. */
- write_pc_pid (breakpoint_pc, ecs->ptid);
+ breakpoint_pc = regcache_read_pc (regcache)
+ - gdbarch_decr_pc_after_break (gdbarch);
+
+ /* Check whether there actually is a software breakpoint inserted at
+ that location.
+
+ If in non-stop mode, a race condition is possible where we've
+ removed a breakpoint, but stop events for that breakpoint were
+ already queued and arrive later. To suppress those spurious
+ SIGTRAPs, we keep a list of such breakpoint locations for a bit,
+ and retire them after a number of stop events are reported. */
+ if (software_breakpoint_inserted_here_p (breakpoint_pc)
+ || (non_stop && moribund_breakpoint_here_p (breakpoint_pc)))
+ {
+ struct cleanup *old_cleanups = NULL;
+ if (RECORD_IS_USED)
+ old_cleanups = record_gdb_operation_disable_set ();
+
+ /* When using hardware single-step, a SIGTRAP is reported for both
+ a completed single-step and a software breakpoint. Need to
+ differentiate between the two, as the latter needs adjusting
+ but the former does not.
+
+ The SIGTRAP can be due to a completed hardware single-step only if
+ - we didn't insert software single-step breakpoints
+ - the thread to be examined is still the current thread
+ - this thread is currently being stepped
+
+ If any of these events did not occur, we must have stopped due
+ to hitting a software breakpoint, and have to back up to the
+ breakpoint address.
+
+ As a special case, we could have hardware single-stepped a
+ software breakpoint. In this case (prev_pc == breakpoint_pc),
+ we also need to back up to the breakpoint address. */
+
+ if (singlestep_breakpoints_inserted_p
+ || !ptid_equal (ecs->ptid, inferior_ptid)
+ || !currently_stepping (ecs->event_thread)
+ || ecs->event_thread->prev_pc == breakpoint_pc)
+ regcache_write_pc (regcache, breakpoint_pc);
+
+ if (RECORD_IS_USED)
+ do_cleanups (old_cleanups);
}
- else
+}
+
+void
+init_infwait_state (void)
+{
+ waiton_ptid = pid_to_ptid (-1);
+ infwait_state = infwait_normal_state;
+}
+
+void
+error_is_running (void)
+{
+ error (_("\
+Cannot execute this command while the selected thread is running."));
+}
+
+void
+ensure_not_running (void)
+{
+ if (is_running (inferior_ptid))
+ error_is_running ();
+}
+
+static int
+stepped_in_from (struct frame_info *frame, struct frame_id step_frame_id)
+{
+ for (frame = get_prev_frame (frame);
+ frame != NULL;
+ frame = get_prev_frame (frame))
{
- /* When using hardware single-step, a SIGTRAP is reported for
- both a completed single-step and a software breakpoint. Need
- to differentiate between the two as the latter needs
- adjusting but the former does not.
-
- When the thread to be examined does not match the current thread
- context we can't use currently_stepping, so assume no
- single-stepping in this case. */
- if (ptid_equal (ecs->ptid, inferior_ptid) && currently_stepping (ecs))
- {
- if (prev_pc == breakpoint_pc
- && software_breakpoint_inserted_here_p (breakpoint_pc))
- /* Hardware single-stepped a software breakpoint (as
- occures when the inferior is resumed with PC pointing
- at not-yet-hit software breakpoint). Since the
- breakpoint really is executed, the inferior needs to be
- backed up to the breakpoint address. */
- write_pc_pid (breakpoint_pc, ecs->ptid);
- }
- else
- {
- if (software_breakpoint_inserted_here_p (breakpoint_pc))
- /* The inferior was free running (i.e., no hardware
- single-step and no possibility of a false SIGTRAP) and
- hit a software breakpoint. */
- write_pc_pid (breakpoint_pc, ecs->ptid);
- }
+ if (frame_id_eq (get_frame_id (frame), step_frame_id))
+ return 1;
+ if (get_frame_type (frame) != INLINE_FRAME)
+ break;
}
+
+ return 0;
}
/* Given an execution control state that has been freshly filled in
by an event from the inferior, figure out what it means and take
appropriate action. */
-int stepped_after_stopped_by_watchpoint;
-
void
handle_inferior_event (struct execution_control_state *ecs)
{
- /* NOTE: bje/2005-05-02: If you're looking at this code and thinking
- that the variable stepped_after_stopped_by_watchpoint isn't used,
- then you're wrong! See remote.c:remote_stopped_data_address. */
-
+ struct frame_info *frame;
+ struct gdbarch *gdbarch;
int sw_single_step_trap_p = 0;
- int stopped_by_watchpoint = -1; /* Mark as unknown. */
+ int stopped_by_watchpoint;
+ int stepped_after_stopped_by_watchpoint = 0;
+ struct symtab_and_line stop_pc_sal;
+ enum stop_kind stop_soon;
+
+ if (ecs->ws.kind != TARGET_WAITKIND_EXITED
+ && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED
+ && ecs->ws.kind != TARGET_WAITKIND_IGNORE)
+ {
+ struct inferior *inf = find_inferior_pid (ptid_get_pid (ecs->ptid));
+ gdb_assert (inf);
+ stop_soon = inf->stop_soon;
+ }
+ else
+ stop_soon = NO_STOP_QUIETLY;
/* Cache the last pid/waitstatus. */
target_last_wait_ptid = ecs->ptid;
- target_last_waitstatus = *ecs->wp;
+ target_last_waitstatus = ecs->ws;
+
+ /* Always clear state belonging to the previous time we stopped. */
+ stop_stack_dummy = 0;
+
+ /* If it's a new process, add it to the thread database */
+ ecs->new_thread_event = (!ptid_equal (ecs->ptid, inferior_ptid)
+ && !ptid_equal (ecs->ptid, minus_one_ptid)
+ && !in_thread_list (ecs->ptid));
+
+ if (ecs->ws.kind != TARGET_WAITKIND_EXITED
+ && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED && ecs->new_thread_event)
+ add_thread (ecs->ptid);
+
+ ecs->event_thread = find_thread_ptid (ecs->ptid);
+
+ /* Dependent on valid ECS->EVENT_THREAD. */
adjust_pc_after_break (ecs);
- switch (ecs->infwait_state)
+ /* Dependent on the current PC value modified by adjust_pc_after_break. */
+ reinit_frame_cache ();
+
+ if (ecs->ws.kind != TARGET_WAITKIND_IGNORE)
+ {
+ breakpoint_retire_moribund ();
+
+ /* Mark the non-executing threads accordingly. In all-stop, all
+ threads of all processes are stopped when we get any event
+ reported. In non-stop mode, only the event thread stops. If
+ we're handling a process exit in non-stop mode, there's
+ nothing to do, as threads of the dead process are gone, and
+ threads of any other process were left running. */
+ if (!non_stop)
+ set_executing (minus_one_ptid, 0);
+ else if (ecs->ws.kind != TARGET_WAITKIND_SIGNALLED
+ && ecs->ws.kind != TARGET_WAITKIND_EXITED)
+ set_executing (inferior_ptid, 0);
+ }
+
+ switch (infwait_state)
{
case infwait_thread_hop_state:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: infwait_thread_hop_state\n");
/* Cancel the waiton_ptid. */
- ecs->waiton_ptid = pid_to_ptid (-1);
+ waiton_ptid = pid_to_ptid (-1);
break;
case infwait_normal_state:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: infwait_normal_state\n");
- stepped_after_stopped_by_watchpoint = 0;
+ break;
+
+ case infwait_step_watch_state:
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: infwait_step_watch_state\n");
+
+ stepped_after_stopped_by_watchpoint = 1;
break;
case infwait_nonstep_watch_state:
default:
internal_error (__FILE__, __LINE__, _("bad switch"));
}
- ecs->infwait_state = infwait_normal_state;
-
- flush_cached_frames ();
-
- /* If it's a new process, add it to the thread database */
-
- ecs->new_thread_event = (!ptid_equal (ecs->ptid, inferior_ptid)
- && !ptid_equal (ecs->ptid, minus_one_ptid)
- && !in_thread_list (ecs->ptid));
-
- if (ecs->ws.kind != TARGET_WAITKIND_EXITED
- && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED && ecs->new_thread_event)
- {
- add_thread (ecs->ptid);
-
- ui_out_text (uiout, "[New ");
- ui_out_text (uiout, target_pid_or_tid_to_str (ecs->ptid));
- ui_out_text (uiout, "]\n");
- }
+ infwait_state = infwait_normal_state;
switch (ecs->ws.kind)
{
case TARGET_WAITKIND_LOADED:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_LOADED\n");
- /* Ignore gracefully during startup of the inferior, as it
- might be the shell which has just loaded some objects,
- otherwise add the symbols for the newly loaded objects. */
-#ifdef SOLIB_ADD
+ /* Ignore gracefully during startup of the inferior, as it might
+ be the shell which has just loaded some objects, otherwise
+ add the symbols for the newly loaded objects. Also ignore at
+ the beginning of an attach or remote session; we will query
+ the full list of libraries once the connection is
+ established. */
if (stop_soon == NO_STOP_QUIETLY)
{
- /* Remove breakpoints, SOLIB_ADD might adjust
- breakpoint addresses via breakpoint_re_set. */
- if (breakpoints_inserted)
- remove_breakpoints ();
-
/* Check for any newly added shared libraries if we're
supposed to be adding them automatically. Switch
terminal for any messages produced by
operations such as address => section name and hence
require the table to contain all sections (including
those found in shared libraries). */
- /* NOTE: cagney/2003-11-25: Pass current_target and not
- exec_ops to SOLIB_ADD. This is because current GDB is
- only tooled to propagate section_table changes out from
- the "current_target" (see target_resize_to_sections), and
- not up from the exec stratum. This, of course, isn't
- right. "infrun.c" should only interact with the
- exec/process stratum, instead relying on the target stack
- to propagate relevant changes (stop, section table
- changed, ...) up to other layers. */
+#ifdef SOLIB_ADD
SOLIB_ADD (NULL, 0, ¤t_target, auto_solib_add);
+#else
+ solib_add (NULL, 0, ¤t_target, auto_solib_add);
+#endif
target_terminal_inferior ();
- /* Reinsert breakpoints and continue. */
- if (breakpoints_inserted)
+ /* If requested, stop when the dynamic linker notifies
+ gdb of events. This allows the user to get control
+ and place breakpoints in initializer routines for
+ dynamically loaded objects (among other things). */
+ if (stop_on_solib_events)
+ {
+ stop_stepping (ecs);
+ return;
+ }
+
+ /* NOTE drow/2007-05-11: This might be a good place to check
+ for "catch load". */
+ }
+
+ /* If we are skipping through a shell, or through shared library
+ loading that we aren't interested in, resume the program. If
+ we're running the program normally, also resume. But stop if
+ we're attaching or setting up a remote connection. */
+ if (stop_soon == STOP_QUIETLY || stop_soon == NO_STOP_QUIETLY)
+ {
+ /* Loading of shared libraries might have changed breakpoint
+ addresses. Make sure new breakpoints are inserted. */
+ if (stop_soon == NO_STOP_QUIETLY
+ && !breakpoints_always_inserted_mode ())
insert_breakpoints ();
+ resume (0, TARGET_SIGNAL_0);
+ prepare_to_wait (ecs);
+ return;
}
-#endif
- resume (0, TARGET_SIGNAL_0);
- prepare_to_wait (ecs);
- return;
+
+ break;
case TARGET_WAITKIND_SPURIOUS:
if (debug_infrun)
case TARGET_WAITKIND_EXITED:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_EXITED\n");
+ inferior_ptid = ecs->ptid;
target_terminal_ours (); /* Must do this before mourn anyway */
print_stop_reason (EXITED, ecs->ws.value.integer);
/* Record the exit code in the convenience variable $_exitcode, so
that the user can inspect this again later. */
- set_internalvar (lookup_internalvar ("_exitcode"),
- value_from_longest (builtin_type_int,
- (LONGEST) ecs->ws.value.integer));
+ set_internalvar_integer (lookup_internalvar ("_exitcode"),
+ (LONGEST) ecs->ws.value.integer);
gdb_flush (gdb_stdout);
target_mourn_inferior ();
- singlestep_breakpoints_inserted_p = 0; /*SOFTWARE_SINGLE_STEP_P() */
+ singlestep_breakpoints_inserted_p = 0;
stop_print_frame = 0;
stop_stepping (ecs);
return;
case TARGET_WAITKIND_SIGNALLED:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SIGNALLED\n");
+ inferior_ptid = ecs->ptid;
stop_print_frame = 0;
- stop_signal = ecs->ws.value.sig;
target_terminal_ours (); /* Must do this before mourn anyway */
/* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
may be needed. */
target_mourn_inferior ();
- print_stop_reason (SIGNAL_EXITED, stop_signal);
- singlestep_breakpoints_inserted_p = 0; /*SOFTWARE_SINGLE_STEP_P() */
+ print_stop_reason (SIGNAL_EXITED, ecs->ws.value.sig);
+ singlestep_breakpoints_inserted_p = 0;
stop_stepping (ecs);
return;
case TARGET_WAITKIND_VFORKED:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_FORKED\n");
- stop_signal = TARGET_SIGNAL_TRAP;
- pending_follow.kind = ecs->ws.kind;
-
- pending_follow.fork_event.parent_pid = PIDGET (ecs->ptid);
- pending_follow.fork_event.child_pid = ecs->ws.value.related_pid;
if (!ptid_equal (ecs->ptid, inferior_ptid))
{
- context_switch (ecs);
- flush_cached_frames ();
+ context_switch (ecs->ptid);
+ reinit_frame_cache ();
+ }
+
+ /* Immediately detach breakpoints from the child before there's
+ any chance of letting the user delete breakpoints from the
+ breakpoint lists. If we don't do this early, it's easy to
+ leave left over traps in the child, vis: "break foo; catch
+ fork; c; <fork>; del; c; <child calls foo>". We only follow
+ the fork on the last `continue', and by that time the
+ breakpoint at "foo" is long gone from the breakpoint table.
+ If we vforked, then we don't need to unpatch here, since both
+ parent and child are sharing the same memory pages; we'll
+ need to unpatch at follow/detach time instead to be certain
+ that new breakpoints added between catchpoint hit time and
+ vfork follow are detached. */
+ if (ecs->ws.kind != TARGET_WAITKIND_VFORKED)
+ {
+ int child_pid = ptid_get_pid (ecs->ws.value.related_pid);
+
+ /* This won't actually modify the breakpoint list, but will
+ physically remove the breakpoints from the child. */
+ detach_breakpoints (child_pid);
}
- stop_pc = read_pc ();
+ /* In case the event is caught by a catchpoint, remember that
+ the event is to be followed at the next resume of the thread,
+ and not immediately. */
+ ecs->event_thread->pending_follow = ecs->ws;
+
+ stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
- stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid, 0);
+ ecs->event_thread->stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid);
- ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
+ ecs->random_signal = !bpstat_explains_signal (ecs->event_thread->stop_bpstat);
/* If no catchpoint triggered for this, then keep going. */
if (ecs->random_signal)
{
- stop_signal = TARGET_SIGNAL_0;
- keep_going (ecs);
+ int should_resume;
+
+ ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
+
+ should_resume = follow_fork ();
+
+ ecs->event_thread = inferior_thread ();
+ ecs->ptid = inferior_ptid;
+
+ if (should_resume)
+ keep_going (ecs);
+ else
+ stop_stepping (ecs);
return;
}
+ ecs->event_thread->stop_signal = TARGET_SIGNAL_TRAP;
goto process_event_stop_test;
case TARGET_WAITKIND_EXECD:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_EXECD\n");
- stop_signal = TARGET_SIGNAL_TRAP;
-
- /* NOTE drow/2002-12-05: This code should be pushed down into the
- target_wait function. Until then following vfork on HP/UX 10.20
- is probably broken by this. Of course, it's broken anyway. */
- /* Is this a target which reports multiple exec events per actual
- call to exec()? (HP-UX using ptrace does, for example.) If so,
- ignore all but the last one. Just resume the exec'r, and wait
- for the next exec event. */
- if (inferior_ignoring_leading_exec_events)
- {
- inferior_ignoring_leading_exec_events--;
- target_resume (ecs->ptid, 0, TARGET_SIGNAL_0);
- prepare_to_wait (ecs);
- return;
- }
- inferior_ignoring_leading_exec_events =
- target_reported_exec_events_per_exec_call () - 1;
- pending_follow.execd_pathname =
- savestring (ecs->ws.value.execd_pathname,
- strlen (ecs->ws.value.execd_pathname));
-
- /* This causes the eventpoints and symbol table to be reset. Must
- do this now, before trying to determine whether to stop. */
- follow_exec (PIDGET (inferior_ptid), pending_follow.execd_pathname);
- xfree (pending_follow.execd_pathname);
+ if (!ptid_equal (ecs->ptid, inferior_ptid))
+ {
+ context_switch (ecs->ptid);
+ reinit_frame_cache ();
+ }
- stop_pc = read_pc_pid (ecs->ptid);
- ecs->saved_inferior_ptid = inferior_ptid;
- inferior_ptid = ecs->ptid;
+ stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
- stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid, 0);
+ /* This causes the eventpoints and symbol table to be reset.
+ Must do this now, before trying to determine whether to
+ stop. */
+ follow_exec (inferior_ptid, ecs->ws.value.execd_pathname);
- ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
- inferior_ptid = ecs->saved_inferior_ptid;
+ ecs->event_thread->stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid);
+ ecs->random_signal = !bpstat_explains_signal (ecs->event_thread->stop_bpstat);
- if (!ptid_equal (ecs->ptid, inferior_ptid))
- {
- context_switch (ecs);
- flush_cached_frames ();
- }
+ /* Note that this may be referenced from inside
+ bpstat_stop_status above, through inferior_has_execd. */
+ xfree (ecs->ws.value.execd_pathname);
+ ecs->ws.value.execd_pathname = NULL;
/* If no catchpoint triggered for this, then keep going. */
if (ecs->random_signal)
{
- stop_signal = TARGET_SIGNAL_0;
+ ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
keep_going (ecs);
return;
}
+ ecs->event_thread->stop_signal = TARGET_SIGNAL_TRAP;
goto process_event_stop_test;
/* Be careful not to try to gather much state about a thread
case TARGET_WAITKIND_STOPPED:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_STOPPED\n");
- stop_signal = ecs->ws.value.sig;
+ ecs->event_thread->stop_signal = ecs->ws.value.sig;
break;
+ case TARGET_WAITKIND_NO_HISTORY:
+ /* Reverse execution: target ran out of history info. */
+ stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
+ print_stop_reason (NO_HISTORY, 0);
+ stop_stepping (ecs);
+ return;
+
/* We had an event in the inferior, but we are not interested
in handling it at this level. The lower layers have already
done what needs to be done, if anything.
return;
}
- /* We may want to consider not doing a resume here in order to give
- the user a chance to play with the new thread. It might be good
- to make that a user-settable option. */
-
- /* At this point, all threads are stopped (happens automatically in
- either the OS or the native code). Therefore we need to continue
- all threads in order to make progress. */
if (ecs->new_thread_event)
{
+ if (non_stop)
+ /* Non-stop assumes that the target handles adding new threads
+ to the thread list. */
+ internal_error (__FILE__, __LINE__, "\
+targets should add new threads to the thread list themselves in non-stop mode.");
+
+ /* We may want to consider not doing a resume here in order to
+ give the user a chance to play with the new thread. It might
+ be good to make that a user-settable option. */
+
+ /* At this point, all threads are stopped (happens automatically
+ in either the OS or the native code). Therefore we need to
+ continue all threads in order to make progress. */
+
+ if (!ptid_equal (ecs->ptid, inferior_ptid))
+ context_switch (ecs->ptid);
target_resume (RESUME_ALL, 0, TARGET_SIGNAL_0);
prepare_to_wait (ecs);
return;
}
- stop_pc = read_pc_pid (ecs->ptid);
+ if (ecs->ws.kind == TARGET_WAITKIND_STOPPED)
+ {
+ /* Do we need to clean up the state of a thread that has
+ completed a displaced single-step? (Doing so usually affects
+ the PC, so do it here, before we set stop_pc.) */
+ displaced_step_fixup (ecs->ptid, ecs->event_thread->stop_signal);
+
+ /* If we either finished a single-step or hit a breakpoint, but
+ the user wanted this thread to be stopped, pretend we got a
+ SIG0 (generic unsignaled stop). */
+
+ if (ecs->event_thread->stop_requested
+ && ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP)
+ ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
+ }
+
+ stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
if (debug_infrun)
- fprintf_unfiltered (gdb_stdlog, "infrun: stop_pc = 0x%s\n", paddr_nz (stop_pc));
+ {
+ fprintf_unfiltered (gdb_stdlog, "infrun: stop_pc = 0x%s\n",
+ paddr_nz (stop_pc));
+ if (target_stopped_by_watchpoint ())
+ {
+ CORE_ADDR addr;
+ fprintf_unfiltered (gdb_stdlog, "infrun: stopped by watchpoint\n");
+
+ if (target_stopped_data_address (¤t_target, &addr))
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: stopped data address = 0x%s\n",
+ paddr_nz (addr));
+ else
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: (no data address available)\n");
+ }
+ }
if (stepping_past_singlestep_breakpoint)
{
- gdb_assert (SOFTWARE_SINGLE_STEP_P ()
- && singlestep_breakpoints_inserted_p);
+ gdb_assert (singlestep_breakpoints_inserted_p);
gdb_assert (ptid_equal (singlestep_ptid, ecs->ptid));
gdb_assert (!ptid_equal (singlestep_ptid, saved_singlestep_ptid));
/* We've either finished single-stepping past the single-step
breakpoint, or stopped for some other reason. It would be nice if
we could tell, but we can't reliably. */
- if (stop_signal == TARGET_SIGNAL_TRAP)
+ if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP)
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: stepping_past_singlestep_breakpoint\n");
/* Pull the single step breakpoints out of the target. */
- SOFTWARE_SINGLE_STEP (0, 0);
+ remove_single_step_breakpoints ();
singlestep_breakpoints_inserted_p = 0;
ecs->random_signal = 0;
- ecs->ptid = saved_singlestep_ptid;
- context_switch (ecs);
+ context_switch (saved_singlestep_ptid);
if (deprecated_context_hook)
deprecated_context_hook (pid_to_thread_id (ecs->ptid));
}
}
- stepping_past_singlestep_breakpoint = 0;
+ if (!ptid_equal (deferred_step_ptid, null_ptid))
+ {
+ /* In non-stop mode, there's never a deferred_step_ptid set. */
+ gdb_assert (!non_stop);
+
+ /* If we stopped for some other reason than single-stepping, ignore
+ the fact that we were supposed to switch back. */
+ if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP)
+ {
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: handling deferred step\n");
+
+ /* Pull the single step breakpoints out of the target. */
+ if (singlestep_breakpoints_inserted_p)
+ {
+ remove_single_step_breakpoints ();
+ singlestep_breakpoints_inserted_p = 0;
+ }
+
+ /* Note: We do not call context_switch at this point, as the
+ context is already set up for stepping the original thread. */
+ switch_to_thread (deferred_step_ptid);
+ deferred_step_ptid = null_ptid;
+ /* Suppress spurious "Switching to ..." message. */
+ previous_inferior_ptid = inferior_ptid;
+
+ resume (1, TARGET_SIGNAL_0);
+ prepare_to_wait (ecs);
+ return;
+ }
+
+ deferred_step_ptid = null_ptid;
+ }
/* See if a thread hit a thread-specific breakpoint that was meant for
another thread. If so, then step that thread past the breakpoint,
and continue it. */
- if (stop_signal == TARGET_SIGNAL_TRAP)
+ if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP)
{
int thread_hop_needed = 0;
/* Check if a regular breakpoint has been hit before checking
for a potential single step breakpoint. Otherwise, GDB will
not see this breakpoint hit when stepping onto breakpoints. */
- if (breakpoints_inserted && breakpoint_here_p (stop_pc))
+ if (regular_breakpoint_inserted_here_p (stop_pc))
{
ecs->random_signal = 0;
if (!breakpoint_thread_match (stop_pc, ecs->ptid))
thread_hop_needed = 1;
}
- else if (SOFTWARE_SINGLE_STEP_P () && singlestep_breakpoints_inserted_p)
+ else if (singlestep_breakpoints_inserted_p)
{
+ /* We have not context switched yet, so this should be true
+ no matter which thread hit the singlestep breakpoint. */
+ gdb_assert (ptid_equal (inferior_ptid, singlestep_ptid));
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog, "infrun: software single step "
+ "trap for %s\n",
+ target_pid_to_str (ecs->ptid));
+
ecs->random_signal = 0;
/* The call to in_thread_list is necessary because PTIDs sometimes
change when we go from single-threaded to multi-threaded. If
if (!ptid_equal (singlestep_ptid, ecs->ptid)
&& in_thread_list (singlestep_ptid))
{
- thread_hop_needed = 1;
- stepping_past_singlestep_breakpoint = 1;
- saved_singlestep_ptid = singlestep_ptid;
+ /* If the PC of the thread we were trying to single-step
+ has changed, discard this event (which we were going
+ to ignore anyway), and pretend we saw that thread
+ trap. This prevents us continuously moving the
+ single-step breakpoint forward, one instruction at a
+ time. If the PC has changed, then the thread we were
+ trying to single-step has trapped or been signalled,
+ but the event has not been reported to GDB yet.
+
+ There might be some cases where this loses signal
+ information, if a signal has arrived at exactly the
+ same time that the PC changed, but this is the best
+ we can do with the information available. Perhaps we
+ should arrange to report all events for all threads
+ when they stop, or to re-poll the remote looking for
+ this particular thread (i.e. temporarily enable
+ schedlock). */
+
+ CORE_ADDR new_singlestep_pc
+ = regcache_read_pc (get_thread_regcache (singlestep_ptid));
+
+ if (new_singlestep_pc != singlestep_pc)
+ {
+ enum target_signal stop_signal;
+
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog, "infrun: unexpected thread,"
+ " but expected thread advanced also\n");
+
+ /* The current context still belongs to
+ singlestep_ptid. Don't swap here, since that's
+ the context we want to use. Just fudge our
+ state and continue. */
+ stop_signal = ecs->event_thread->stop_signal;
+ ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
+ ecs->ptid = singlestep_ptid;
+ ecs->event_thread = find_thread_ptid (ecs->ptid);
+ ecs->event_thread->stop_signal = stop_signal;
+ stop_pc = new_singlestep_pc;
+ }
+ else
+ {
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: unexpected thread\n");
+
+ thread_hop_needed = 1;
+ stepping_past_singlestep_breakpoint = 1;
+ saved_singlestep_ptid = singlestep_ptid;
+ }
}
}
if (thread_hop_needed)
{
- int remove_status;
+ struct regcache *thread_regcache;
+ int remove_status = 0;
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: thread_hop_needed\n");
+ /* Switch context before touching inferior memory, the
+ previous thread may have exited. */
+ if (!ptid_equal (inferior_ptid, ecs->ptid))
+ context_switch (ecs->ptid);
+
/* Saw a breakpoint, but it was hit by the wrong thread.
Just continue. */
- if (SOFTWARE_SINGLE_STEP_P () && singlestep_breakpoints_inserted_p)
+ if (singlestep_breakpoints_inserted_p)
{
/* Pull the single step breakpoints out of the target. */
- SOFTWARE_SINGLE_STEP (0, 0);
+ remove_single_step_breakpoints ();
singlestep_breakpoints_inserted_p = 0;
}
- remove_status = remove_breakpoints ();
+ /* If the arch can displace step, don't remove the
+ breakpoints. */
+ thread_regcache = get_thread_regcache (ecs->ptid);
+ if (!use_displaced_stepping (get_regcache_arch (thread_regcache)))
+ remove_status = remove_breakpoints ();
+
/* Did we fail to remove breakpoints? If so, try
to set the PC past the bp. (There's at least
one situation in which we can fail to remove
process until the child exits (well, okay, not
then either :-) or execs. */
if (remove_status != 0)
- {
- /* FIXME! This is obviously non-portable! */
- write_pc_pid (stop_pc + 4, ecs->ptid);
- /* We need to restart all the threads now,
- * unles we're running in scheduler-locked mode.
- * Use currently_stepping to determine whether to
- * step or continue.
- */
- /* FIXME MVS: is there any reason not to call resume()? */
- if (scheduler_mode == schedlock_on)
- target_resume (ecs->ptid,
- currently_stepping (ecs), TARGET_SIGNAL_0);
- else
- target_resume (RESUME_ALL,
- currently_stepping (ecs), TARGET_SIGNAL_0);
- prepare_to_wait (ecs);
- return;
- }
+ error (_("Cannot step over breakpoint hit in wrong thread"));
else
{ /* Single step */
- breakpoints_inserted = 0;
- if (!ptid_equal (inferior_ptid, ecs->ptid))
- context_switch (ecs);
- ecs->waiton_ptid = ecs->ptid;
- ecs->wp = &(ecs->ws);
- ecs->another_trap = 1;
-
- ecs->infwait_state = infwait_thread_hop_state;
+ if (!non_stop)
+ {
+ /* Only need to require the next event from this
+ thread in all-stop mode. */
+ waiton_ptid = ecs->ptid;
+ infwait_state = infwait_thread_hop_state;
+ }
+
+ ecs->event_thread->stepping_over_breakpoint = 1;
keep_going (ecs);
registers_changed ();
return;
}
}
- else if (SOFTWARE_SINGLE_STEP_P () && singlestep_breakpoints_inserted_p)
+ else if (singlestep_breakpoints_inserted_p)
{
sw_single_step_trap_p = 1;
ecs->random_signal = 0;
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: context switch\n");
- context_switch (ecs);
+ context_switch (ecs->ptid);
if (deprecated_context_hook)
deprecated_context_hook (pid_to_thread_id (ecs->ptid));
-
- flush_cached_frames ();
}
- if (SOFTWARE_SINGLE_STEP_P () && singlestep_breakpoints_inserted_p)
+ /* At this point, get hold of the now-current thread's frame. */
+ frame = get_current_frame ();
+ gdbarch = get_frame_arch (frame);
+
+ if (singlestep_breakpoints_inserted_p)
{
/* Pull the single step breakpoints out of the target. */
- SOFTWARE_SINGLE_STEP (0, 0);
+ remove_single_step_breakpoints ();
singlestep_breakpoints_inserted_p = 0;
}
- /* It may not be necessary to disable the watchpoint to stop over
- it. For example, the PA can (with some kernel cooperation)
- single step over a watchpoint without disabling the watchpoint. */
- if (HAVE_STEPPABLE_WATCHPOINT && STOPPED_BY_WATCHPOINT (ecs->ws))
- {
- if (debug_infrun)
- fprintf_unfiltered (gdb_stdlog, "infrun: STOPPED_BY_WATCHPOINT\n");
- resume (1, 0);
- prepare_to_wait (ecs);
- return;
- }
+ if (stepped_after_stopped_by_watchpoint)
+ stopped_by_watchpoint = 0;
+ else
+ stopped_by_watchpoint = watchpoints_triggered (&ecs->ws);
- /* It is far more common to need to disable a watchpoint to step
- the inferior over it. FIXME. What else might a debug
- register or page protection watchpoint scheme need here? */
- if (HAVE_NONSTEPPABLE_WATCHPOINT && STOPPED_BY_WATCHPOINT (ecs->ws))
+ /* If necessary, step over this watchpoint. We'll be back to display
+ it in a moment. */
+ if (stopped_by_watchpoint
+ && (target_have_steppable_watchpoint
+ || gdbarch_have_nonsteppable_watchpoint (gdbarch)))
{
/* At this point, we are stopped at an instruction which has
attempted to write to a piece of memory under control of
In order to make watchpoints work `right', we really need
to complete the memory write, and then evaluate the
- watchpoint expression. The following code does that by
- removing the watchpoint (actually, all watchpoints and
- breakpoints), single-stepping the target, re-inserting
- watchpoints, and then falling through to let normal
- single-step processing handle proceed. Since this
- includes evaluating watchpoints, things will come to a
- stop in the correct manner. */
+ watchpoint expression. We do this by single-stepping the
+ target.
- if (debug_infrun)
- fprintf_unfiltered (gdb_stdlog, "infrun: STOPPED_BY_WATCHPOINT\n");
- remove_breakpoints ();
- registers_changed ();
- target_resume (ecs->ptid, 1, TARGET_SIGNAL_0); /* Single step */
+ It may not be necessary to disable the watchpoint to stop over
+ it. For example, the PA can (with some kernel cooperation)
+ single step over a watchpoint without disabling the watchpoint.
- ecs->waiton_ptid = ecs->ptid;
- ecs->wp = &(ecs->ws);
- ecs->infwait_state = infwait_nonstep_watch_state;
+ It is far more common to need to disable a watchpoint to step
+ the inferior over it. If we have non-steppable watchpoints,
+ we must disable the current watchpoint; it's simplest to
+ disable all watchpoints and breakpoints. */
+ int hw_step = 1;
+
+ if (!target_have_steppable_watchpoint)
+ remove_breakpoints ();
+ /* Single step */
+ hw_step = maybe_software_singlestep (gdbarch, stop_pc);
+ target_resume (ecs->ptid, hw_step, TARGET_SIGNAL_0);
+ registers_changed ();
+ waiton_ptid = ecs->ptid;
+ if (target_have_steppable_watchpoint)
+ infwait_state = infwait_step_watch_state;
+ else
+ infwait_state = infwait_nonstep_watch_state;
prepare_to_wait (ecs);
return;
}
- /* It may be possible to simply continue after a watchpoint. */
- if (HAVE_CONTINUABLE_WATCHPOINT)
- stopped_by_watchpoint = STOPPED_BY_WATCHPOINT (ecs->ws);
-
ecs->stop_func_start = 0;
ecs->stop_func_end = 0;
ecs->stop_func_name = 0;
will both be 0 if it doesn't work. */
find_pc_partial_function (stop_pc, &ecs->stop_func_name,
&ecs->stop_func_start, &ecs->stop_func_end);
- ecs->stop_func_start += DEPRECATED_FUNCTION_START_OFFSET;
- ecs->another_trap = 0;
- bpstat_clear (&stop_bpstat);
- stop_step = 0;
- stop_stack_dummy = 0;
+ ecs->stop_func_start
+ += gdbarch_deprecated_function_start_offset (gdbarch);
+ ecs->event_thread->stepping_over_breakpoint = 0;
+ bpstat_clear (&ecs->event_thread->stop_bpstat);
+ ecs->event_thread->stop_step = 0;
stop_print_frame = 1;
ecs->random_signal = 0;
stopped_by_random_signal = 0;
- breakpoints_failed = 0;
- if (stop_signal == TARGET_SIGNAL_TRAP
- && trap_expected
- && gdbarch_single_step_through_delay_p (current_gdbarch)
- && currently_stepping (ecs))
+ /* Hide inlined functions starting here, unless we just performed stepi or
+ nexti. After stepi and nexti, always show the innermost frame (not any
+ inline function call sites). */
+ if (ecs->event_thread->step_range_end != 1)
+ skip_inline_frames (ecs->ptid);
+
+ if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP
+ && ecs->event_thread->trap_expected
+ && gdbarch_single_step_through_delay_p (gdbarch)
+ && currently_stepping (ecs->event_thread))
{
- /* We're trying to step of a breakpoint. Turns out that we're
+ /* We're trying to step off a breakpoint. Turns out that we're
also on an instruction that needs to be stepped multiple
times before it's been fully executing. E.g., architectures
with a delay slot. It needs to be stepped twice, once for
the instruction and once for the delay slot. */
int step_through_delay
- = gdbarch_single_step_through_delay (current_gdbarch,
- get_current_frame ());
+ = gdbarch_single_step_through_delay (gdbarch, frame);
if (debug_infrun && step_through_delay)
fprintf_unfiltered (gdb_stdlog, "infrun: step through delay\n");
- if (step_range_end == 0 && step_through_delay)
+ if (ecs->event_thread->step_range_end == 0 && step_through_delay)
{
/* The user issued a continue when stopped at a breakpoint.
Set up for another trap and get out of here. */
- ecs->another_trap = 1;
+ ecs->event_thread->stepping_over_breakpoint = 1;
keep_going (ecs);
return;
}
/* The user issued a step when stopped at a breakpoint.
Maybe we should stop, maybe we should not - the delay
slot *might* correspond to a line of source. In any
- case, don't decide that here, just set ecs->another_trap,
- making sure we single-step again before breakpoints are
- re-inserted. */
- ecs->another_trap = 1;
+ case, don't decide that here, just set
+ ecs->stepping_over_breakpoint, making sure we
+ single-step again before breakpoints are re-inserted. */
+ ecs->event_thread->stepping_over_breakpoint = 1;
}
}
/* Look at the cause of the stop, and decide what to do.
The alternatives are:
- 1) break; to really stop and return to the debugger,
- 2) drop through to start up again
- (set ecs->another_trap to 1 to single step once)
+ 1) stop_stepping and return; to really stop and return to the debugger,
+ 2) keep_going and return to start up again
+ (set ecs->event_thread->stepping_over_breakpoint to 1 to single step once)
3) set ecs->random_signal to 1, and the decision between 1 and 2
will be made according to the signal handling tables. */
when we're trying to execute a breakpoint instruction on a
non-executable stack. This happens for call dummy breakpoints
for architectures like SPARC that place call dummies on the
- stack. */
-
- if (stop_signal == TARGET_SIGNAL_TRAP
- || (breakpoints_inserted
- && (stop_signal == TARGET_SIGNAL_ILL
- || stop_signal == TARGET_SIGNAL_SEGV
- || stop_signal == TARGET_SIGNAL_EMT))
- || stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_NO_SIGSTOP)
+ stack.
+
+ If we're doing a displaced step past a breakpoint, then the
+ breakpoint is always inserted at the original instruction;
+ non-standard signals can't be explained by the breakpoint. */
+ if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP
+ || (! ecs->event_thread->trap_expected
+ && breakpoint_inserted_here_p (stop_pc)
+ && (ecs->event_thread->stop_signal == TARGET_SIGNAL_ILL
+ || ecs->event_thread->stop_signal == TARGET_SIGNAL_SEGV
+ || ecs->event_thread->stop_signal == TARGET_SIGNAL_EMT))
+ || stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_NO_SIGSTOP
+ || stop_soon == STOP_QUIETLY_REMOTE)
{
- if (stop_signal == TARGET_SIGNAL_TRAP && stop_after_trap)
+ if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP && stop_after_trap)
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: stopped\n");
/* This is originated from start_remote(), start_inferior() and
shared libraries hook functions. */
- if (stop_soon == STOP_QUIETLY)
+ if (stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_REMOTE)
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: quietly stopped\n");
}
/* This originates from attach_command(). We need to overwrite
- the stop_signal here, because some kernels don't ignore a
- SIGSTOP in a subsequent ptrace(PTRACE_SONT,SOGSTOP) call.
- See more comments in inferior.h. */
- if (stop_soon == STOP_QUIETLY_NO_SIGSTOP)
+ the stop_signal here, because some kernels don't ignore a
+ SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
+ See more comments in inferior.h. On the other hand, if we
+ get a non-SIGSTOP, report it to the user - assume the backend
+ will handle the SIGSTOP if it should show up later.
+
+ Also consider that the attach is complete when we see a
+ SIGTRAP. Some systems (e.g. Windows), and stubs supporting
+ target extended-remote report it instead of a SIGSTOP
+ (e.g. gdbserver). We already rely on SIGTRAP being our
+ signal, so this is no exception.
+
+ Also consider that the attach is complete when we see a
+ TARGET_SIGNAL_0. In non-stop mode, GDB will explicitly tell
+ the target to stop all threads of the inferior, in case the
+ low level attach operation doesn't stop them implicitly. If
+ they weren't stopped implicitly, then the stub will report a
+ TARGET_SIGNAL_0, meaning: stopped for no particular reason
+ other than GDB's request. */
+ if (stop_soon == STOP_QUIETLY_NO_SIGSTOP
+ && (ecs->event_thread->stop_signal == TARGET_SIGNAL_STOP
+ || ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP
+ || ecs->event_thread->stop_signal == TARGET_SIGNAL_0))
{
stop_stepping (ecs);
- if (stop_signal == TARGET_SIGNAL_STOP)
- stop_signal = TARGET_SIGNAL_0;
+ ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
return;
}
- /* Don't even think about breakpoints if just proceeded over a
- breakpoint. */
- if (stop_signal == TARGET_SIGNAL_TRAP && trap_expected)
- {
- if (debug_infrun)
- fprintf_unfiltered (gdb_stdlog, "infrun: trap expected\n");
- bpstat_clear (&stop_bpstat);
- }
- else
- {
- /* See if there is a breakpoint at the current PC. */
- stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid,
- stopped_by_watchpoint);
-
- /* Following in case break condition called a
- function. */
- stop_print_frame = 1;
- }
+ /* See if there is a breakpoint at the current PC. */
+ ecs->event_thread->stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid);
+
+ /* Following in case break condition called a
+ function. */
+ stop_print_frame = 1;
/* NOTE: cagney/2003-03-29: These two checks for a random signal
at one stage in the past included checks for an inferior
another signal besides SIGTRAP, so check here as well as
above.''
- If someone ever tries to get get call dummys on a
+ If someone ever tries to get call dummys on a
non-executable stack to work (where the target would stop
with something like a SIGSEGV), then those tests might need
to be re-instated. Given, however, that the tests were only
be necessary for call dummies on a non-executable stack on
SPARC. */
- if (stop_signal == TARGET_SIGNAL_TRAP)
+ if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP)
ecs->random_signal
- = !(bpstat_explains_signal (stop_bpstat)
- || trap_expected
- || (step_range_end && step_resume_breakpoint == NULL));
+ = !(bpstat_explains_signal (ecs->event_thread->stop_bpstat)
+ || ecs->event_thread->trap_expected
+ || (ecs->event_thread->step_range_end
+ && ecs->event_thread->step_resume_breakpoint == NULL));
else
{
- ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
+ ecs->random_signal = !bpstat_explains_signal (ecs->event_thread->stop_bpstat);
if (!ecs->random_signal)
- stop_signal = TARGET_SIGNAL_TRAP;
+ ecs->event_thread->stop_signal = TARGET_SIGNAL_TRAP;
}
}
ecs->random_signal = 1;
process_event_stop_test:
+
+ /* Re-fetch current thread's frame in case we did a
+ "goto process_event_stop_test" above. */
+ frame = get_current_frame ();
+ gdbarch = get_frame_arch (frame);
+
/* For the program's own signals, act according to
the signal handling tables. */
int printed = 0;
if (debug_infrun)
- fprintf_unfiltered (gdb_stdlog, "infrun: random signal %d\n", stop_signal);
+ fprintf_unfiltered (gdb_stdlog, "infrun: random signal %d\n",
+ ecs->event_thread->stop_signal);
stopped_by_random_signal = 1;
- if (signal_print[stop_signal])
+ if (signal_print[ecs->event_thread->stop_signal])
{
printed = 1;
target_terminal_ours_for_output ();
- print_stop_reason (SIGNAL_RECEIVED, stop_signal);
+ print_stop_reason (SIGNAL_RECEIVED, ecs->event_thread->stop_signal);
}
- if (signal_stop[stop_signal])
+ /* Always stop on signals if we're either just gaining control
+ of the program, or the user explicitly requested this thread
+ to remain stopped. */
+ if (stop_soon != NO_STOP_QUIETLY
+ || ecs->event_thread->stop_requested
+ || signal_stop_state (ecs->event_thread->stop_signal))
{
stop_stepping (ecs);
return;
target_terminal_inferior ();
/* Clear the signal if it should not be passed. */
- if (signal_program[stop_signal] == 0)
- stop_signal = TARGET_SIGNAL_0;
+ if (signal_program[ecs->event_thread->stop_signal] == 0)
+ ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
- if (prev_pc == read_pc ()
- && !breakpoints_inserted
- && breakpoint_here_p (read_pc ())
- && step_resume_breakpoint == NULL)
+ if (ecs->event_thread->prev_pc == stop_pc
+ && ecs->event_thread->trap_expected
+ && ecs->event_thread->step_resume_breakpoint == NULL)
{
/* We were just starting a new sequence, attempting to
single-step off of a breakpoint and expecting a SIGTRAP.
- Intead this signal arrives. This signal will take us out
+ Instead this signal arrives. This signal will take us out
of the stepping range so GDB needs to remember to, when
the signal handler returns, resume stepping off that
breakpoint. */
code paths as single-step - set a breakpoint at the
signal return address and then, once hit, step off that
breakpoint. */
- insert_step_resume_breakpoint_at_frame (get_current_frame ());
- ecs->step_after_step_resume_breakpoint = 1;
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: signal arrived while stepping over "
+ "breakpoint\n");
+
+ insert_step_resume_breakpoint_at_frame (frame);
+ ecs->event_thread->step_after_step_resume_breakpoint = 1;
keep_going (ecs);
return;
}
- if (step_range_end != 0
- && stop_signal != TARGET_SIGNAL_0
- && stop_pc >= step_range_start && stop_pc < step_range_end
- && frame_id_eq (get_frame_id (get_current_frame ()),
- step_frame_id)
- && step_resume_breakpoint == NULL)
+ if (ecs->event_thread->step_range_end != 0
+ && ecs->event_thread->stop_signal != TARGET_SIGNAL_0
+ && (ecs->event_thread->step_range_start <= stop_pc
+ && stop_pc < ecs->event_thread->step_range_end)
+ && frame_id_eq (get_stack_frame_id (frame),
+ ecs->event_thread->step_stack_frame_id)
+ && ecs->event_thread->step_resume_breakpoint == NULL)
{
/* The inferior is about to take a signal that will take it
out of the single step range. Set a breakpoint at the
Note that this is only needed for a signal delivered
while in the single-step range. Nested signals aren't a
problem as they eventually all return. */
- insert_step_resume_breakpoint_at_frame (get_current_frame ());
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: signal may take us out of "
+ "single-step range\n");
+
+ insert_step_resume_breakpoint_at_frame (frame);
keep_going (ecs);
return;
}
CORE_ADDR jmp_buf_pc;
struct bpstat_what what;
- what = bpstat_what (stop_bpstat);
+ what = bpstat_what (ecs->event_thread->stop_bpstat);
if (what.call_dummy)
{
switch (what.main_action)
{
case BPSTAT_WHAT_SET_LONGJMP_RESUME:
- /* If we hit the breakpoint at longjmp, disable it for the
- duration of this command. Then, install a temporary
- breakpoint at the target of the jmp_buf. */
- if (debug_infrun)
- fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
- disable_longjmp_breakpoint ();
- remove_breakpoints ();
- breakpoints_inserted = 0;
- if (!GET_LONGJMP_TARGET_P () || !GET_LONGJMP_TARGET (&jmp_buf_pc))
+ /* If we hit the breakpoint at longjmp while stepping, we
+ install a momentary breakpoint at the target of the
+ jmp_buf. */
+
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
+
+ ecs->event_thread->stepping_over_breakpoint = 1;
+
+ if (!gdbarch_get_longjmp_target_p (gdbarch)
+ || !gdbarch_get_longjmp_target (gdbarch, frame, &jmp_buf_pc))
{
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog, "\
+infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME (!gdbarch_get_longjmp_target)\n");
keep_going (ecs);
return;
}
- /* Need to blow away step-resume breakpoint, as it
- interferes with us */
- if (step_resume_breakpoint != NULL)
- {
- delete_step_resume_breakpoint (&step_resume_breakpoint);
- }
+ /* We're going to replace the current step-resume breakpoint
+ with a longjmp-resume breakpoint. */
+ delete_step_resume_breakpoint (ecs->event_thread);
+
+ /* Insert a breakpoint at resume address. */
+ insert_longjmp_resume_breakpoint (jmp_buf_pc);
- set_longjmp_resume_breakpoint (jmp_buf_pc, null_frame_id);
- ecs->handling_longjmp = 1; /* FIXME */
keep_going (ecs);
return;
case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
- case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME_SINGLE:
if (debug_infrun)
- fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
- remove_breakpoints ();
- breakpoints_inserted = 0;
- disable_longjmp_breakpoint ();
- ecs->handling_longjmp = 0; /* FIXME */
- if (what.main_action == BPSTAT_WHAT_CLEAR_LONGJMP_RESUME)
- break;
- /* else fallthrough */
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
+
+ gdb_assert (ecs->event_thread->step_resume_breakpoint != NULL);
+ delete_step_resume_breakpoint (ecs->event_thread);
+
+ ecs->event_thread->stop_step = 1;
+ print_stop_reason (END_STEPPING_RANGE, 0);
+ stop_stepping (ecs);
+ return;
case BPSTAT_WHAT_SINGLE:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_SINGLE\n");
- if (breakpoints_inserted)
- {
- remove_breakpoints ();
- }
- breakpoints_inserted = 0;
- ecs->another_trap = 1;
+ ecs->event_thread->stepping_over_breakpoint = 1;
/* Still need to check other stuff, at least the case
where we are stepping and step out of the right range. */
break;
return;
case BPSTAT_WHAT_STEP_RESUME:
- /* This proably demands a more elegant solution, but, yeah
- right...
-
- This function's use of the simple variable
- step_resume_breakpoint doesn't seem to accomodate
- simultaneously active step-resume bp's, although the
- breakpoint list certainly can.
-
- If we reach here and step_resume_breakpoint is already
- NULL, then apparently we have multiple active
- step-resume bp's. We'll just delete the breakpoint we
- stopped at, and carry on.
-
- Correction: what the code currently does is delete a
- step-resume bp, but it makes no effort to ensure that
- the one deleted is the one currently stopped at. MVS */
-
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
- if (step_resume_breakpoint == NULL)
- {
- step_resume_breakpoint =
- bpstat_find_step_resume_breakpoint (stop_bpstat);
- }
- delete_step_resume_breakpoint (&step_resume_breakpoint);
- if (ecs->step_after_step_resume_breakpoint)
+ delete_step_resume_breakpoint (ecs->event_thread);
+ if (ecs->event_thread->step_after_step_resume_breakpoint)
{
/* Back when the step-resume breakpoint was inserted, we
were trying to single-step off a breakpoint. Go back
to doing that. */
- ecs->step_after_step_resume_breakpoint = 0;
- remove_breakpoints ();
- breakpoints_inserted = 0;
- ecs->another_trap = 1;
+ ecs->event_thread->step_after_step_resume_breakpoint = 0;
+ ecs->event_thread->stepping_over_breakpoint = 1;
+ keep_going (ecs);
+ return;
+ }
+ if (stop_pc == ecs->stop_func_start
+ && execution_direction == EXEC_REVERSE)
+ {
+ /* We are stepping over a function call in reverse, and
+ just hit the step-resume breakpoint at the start
+ address of the function. Go back to single-stepping,
+ which should take us back to the function call. */
+ ecs->event_thread->stepping_over_breakpoint = 1;
keep_going (ecs);
return;
}
- break;
-
- case BPSTAT_WHAT_THROUGH_SIGTRAMP:
- if (debug_infrun)
- fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_THROUGH_SIGTRAMP\n");
- /* If were waiting for a trap, hitting the step_resume_break
- doesn't count as getting it. */
- if (trap_expected)
- ecs->another_trap = 1;
break;
case BPSTAT_WHAT_CHECK_SHLIBS:
- case BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK:
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_CHECK_SHLIBS\n");
- /* Remove breakpoints, we eventually want to step over the
- shlib event breakpoint, and SOLIB_ADD might adjust
- breakpoint addresses via breakpoint_re_set. */
- if (breakpoints_inserted)
- remove_breakpoints ();
- breakpoints_inserted = 0;
/* Check for any newly added shared libraries if we're
supposed to be adding them automatically. Switch
operations such as address => section name and hence
require the table to contain all sections (including
those found in shared libraries). */
- /* NOTE: cagney/2003-11-25: Pass current_target and not
- exec_ops to SOLIB_ADD. This is because current GDB is
- only tooled to propagate section_table changes out from
- the "current_target" (see target_resize_to_sections), and
- not up from the exec stratum. This, of course, isn't
- right. "infrun.c" should only interact with the
- exec/process stratum, instead relying on the target stack
- to propagate relevant changes (stop, section table
- changed, ...) up to other layers. */
#ifdef SOLIB_ADD
SOLIB_ADD (NULL, 0, ¤t_target, auto_solib_add);
#else
#endif
target_terminal_inferior ();
- /* Try to reenable shared library breakpoints, additional
- code segments in shared libraries might be mapped in now. */
- re_enable_breakpoints_in_shlibs ();
-
/* If requested, stop when the dynamic linker notifies
gdb of events. This allows the user to get control
and place breakpoints in initializer routines for
stop_stepping (ecs);
return;
}
-
- /* If we stopped due to an explicit catchpoint, then the
- (see above) call to SOLIB_ADD pulled in any symbols
- from a newly-loaded library, if appropriate.
-
- We do want the inferior to stop, but not where it is
- now, which is in the dynamic linker callback. Rather,
- we would like it stop in the user's program, just after
- the call that caused this catchpoint to trigger. That
- gives the user a more useful vantage from which to
- examine their program's state. */
- else if (what.main_action
- == BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK)
- {
- /* ??rehrauer: If I could figure out how to get the
- right return PC from here, we could just set a temp
- breakpoint and resume. I'm not sure we can without
- cracking open the dld's shared libraries and sniffing
- their unwind tables and text/data ranges, and that's
- not a terribly portable notion.
-
- Until that time, we must step the inferior out of the
- dld callback, and also out of the dld itself (and any
- code or stubs in libdld.sl, such as "shl_load" and
- friends) until we reach non-dld code. At that point,
- we can stop stepping. */
- bpstat_get_triggered_catchpoints (stop_bpstat,
- &ecs->
- stepping_through_solib_catchpoints);
- ecs->stepping_through_solib_after_catch = 1;
-
- /* Be sure to lift all breakpoints, so the inferior does
- actually step past this point... */
- ecs->another_trap = 1;
- break;
- }
else
{
/* We want to step over this breakpoint, then keep going. */
- ecs->another_trap = 1;
+ ecs->event_thread->stepping_over_breakpoint = 1;
break;
}
}
test for stepping. But, if not stepping,
do not stop. */
+ /* In all-stop mode, if we're currently stepping but have stopped in
+ some other thread, we need to switch back to the stepped thread. */
+ if (!non_stop)
+ {
+ struct thread_info *tp;
+ tp = iterate_over_threads (currently_stepping_or_nexting_callback,
+ ecs->event_thread);
+ if (tp)
+ {
+ /* However, if the current thread is blocked on some internal
+ breakpoint, and we simply need to step over that breakpoint
+ to get it going again, do that first. */
+ if ((ecs->event_thread->trap_expected
+ && ecs->event_thread->stop_signal != TARGET_SIGNAL_TRAP)
+ || ecs->event_thread->stepping_over_breakpoint)
+ {
+ keep_going (ecs);
+ return;
+ }
+
+ /* If the stepping thread exited, then don't try to switch
+ back and resume it, which could fail in several different
+ ways depending on the target. Instead, just keep going.
+
+ We can find a stepping dead thread in the thread list in
+ two cases:
+
+ - The target supports thread exit events, and when the
+ target tries to delete the thread from the thread list,
+ inferior_ptid pointed at the exiting thread. In such
+ case, calling delete_thread does not really remove the
+ thread from the list; instead, the thread is left listed,
+ with 'exited' state.
+
+ - The target's debug interface does not support thread
+ exit events, and so we have no idea whatsoever if the
+ previously stepping thread is still alive. For that
+ reason, we need to synchronously query the target
+ now. */
+ if (is_exited (tp->ptid)
+ || !target_thread_alive (tp->ptid))
+ {
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog, "\
+infrun: not switching back to stepped thread, it has vanished\n");
+
+ delete_thread (tp->ptid);
+ keep_going (ecs);
+ return;
+ }
+
+ /* Otherwise, we no longer expect a trap in the current thread.
+ Clear the trap_expected flag before switching back -- this is
+ what keep_going would do as well, if we called it. */
+ ecs->event_thread->trap_expected = 0;
+
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: switching back to stepped thread\n");
+
+ ecs->event_thread = tp;
+ ecs->ptid = tp->ptid;
+ context_switch (ecs->ptid);
+ keep_going (ecs);
+ return;
+ }
+ }
+
/* Are we stepping to get the inferior out of the dynamic linker's
hook (and possibly the dld itself) after catching a shlib
event? */
- if (ecs->stepping_through_solib_after_catch)
+ if (ecs->event_thread->stepping_through_solib_after_catch)
{
#if defined(SOLIB_ADD)
/* Have we reached our destination? If not, keep going. */
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: stepping in dynamic linker\n");
- ecs->another_trap = 1;
+ ecs->event_thread->stepping_over_breakpoint = 1;
keep_going (ecs);
return;
}
fprintf_unfiltered (gdb_stdlog, "infrun: step past dynamic linker\n");
/* Else, stop and report the catchpoint(s) whose triggering
caused us to begin stepping. */
- ecs->stepping_through_solib_after_catch = 0;
- bpstat_clear (&stop_bpstat);
- stop_bpstat = bpstat_copy (ecs->stepping_through_solib_catchpoints);
- bpstat_clear (&ecs->stepping_through_solib_catchpoints);
+ ecs->event_thread->stepping_through_solib_after_catch = 0;
+ bpstat_clear (&ecs->event_thread->stop_bpstat);
+ ecs->event_thread->stop_bpstat
+ = bpstat_copy (ecs->event_thread->stepping_through_solib_catchpoints);
+ bpstat_clear (&ecs->event_thread->stepping_through_solib_catchpoints);
stop_print_frame = 1;
stop_stepping (ecs);
return;
}
- if (step_resume_breakpoint)
+ if (ecs->event_thread->step_resume_breakpoint)
{
if (debug_infrun)
- fprintf_unfiltered (gdb_stdlog, "infrun: step-resume breakpoint\n");
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: step-resume breakpoint is inserted\n");
/* Having a step-resume breakpoint overrides anything
else having to do with stepping commands until
return;
}
- if (step_range_end == 0)
+ if (ecs->event_thread->step_range_end == 0)
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: no stepping, continue\n");
Note that step_range_end is the address of the first instruction
beyond the step range, and NOT the address of the last instruction
- within it! */
- if (stop_pc >= step_range_start && stop_pc < step_range_end)
+ within it!
+
+ Note also that during reverse execution, we may be stepping
+ through a function epilogue and therefore must detect when
+ the current-frame changes in the middle of a line. */
+
+ if (stop_pc >= ecs->event_thread->step_range_start
+ && stop_pc < ecs->event_thread->step_range_end
+ && (execution_direction != EXEC_REVERSE
+ || frame_id_eq (get_frame_id (frame),
+ ecs->event_thread->step_frame_id)))
{
if (debug_infrun)
- fprintf_unfiltered (gdb_stdlog, "infrun: stepping inside range [0x%s-0x%s]\n",
- paddr_nz (step_range_start),
- paddr_nz (step_range_end));
- keep_going (ecs);
+ fprintf_unfiltered (gdb_stdlog, "infrun: stepping inside range [0x%s-0x%s]\n",
+ paddr_nz (ecs->event_thread->step_range_start),
+ paddr_nz (ecs->event_thread->step_range_end));
+
+ /* When stepping backward, stop at beginning of line range
+ (unless it's the function entry point, in which case
+ keep going back to the call point). */
+ if (stop_pc == ecs->event_thread->step_range_start
+ && stop_pc != ecs->stop_func_start
+ && execution_direction == EXEC_REVERSE)
+ {
+ ecs->event_thread->stop_step = 1;
+ print_stop_reason (END_STEPPING_RANGE, 0);
+ stop_stepping (ecs);
+ }
+ else
+ keep_going (ecs);
+
return;
}
/* We stepped out of the stepping range. */
/* If we are stepping at the source level and entered the runtime
- loader dynamic symbol resolution code, we keep on single stepping
- until we exit the run time loader code and reach the callee's
- address. */
- if (step_over_calls == STEP_OVER_UNDEBUGGABLE
-#ifdef IN_SOLIB_DYNSYM_RESOLVE_CODE
- && IN_SOLIB_DYNSYM_RESOLVE_CODE (stop_pc)
-#else
- && in_solib_dynsym_resolve_code (stop_pc)
-#endif
- )
+ loader dynamic symbol resolution code...
+
+ EXEC_FORWARD: we keep on single stepping until we exit the run
+ time loader code and reach the callee's address.
+
+ EXEC_REVERSE: we've already executed the callee (backward), and
+ the runtime loader code is handled just like any other
+ undebuggable function call. Now we need only keep stepping
+ backward through the trampoline code, and that's handled further
+ down, so there is nothing for us to do here. */
+
+ if (execution_direction != EXEC_REVERSE
+ && ecs->event_thread->step_over_calls == STEP_OVER_UNDEBUGGABLE
+ && in_solib_dynsym_resolve_code (stop_pc))
{
CORE_ADDR pc_after_resolver =
- gdbarch_skip_solib_resolver (current_gdbarch, stop_pc);
+ gdbarch_skip_solib_resolver (gdbarch, stop_pc);
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: stepped into dynsym resolve code\n");
return;
}
- if (step_range_end != 1
- && (step_over_calls == STEP_OVER_UNDEBUGGABLE
- || step_over_calls == STEP_OVER_ALL)
- && get_frame_type (get_current_frame ()) == SIGTRAMP_FRAME)
+ if (ecs->event_thread->step_range_end != 1
+ && (ecs->event_thread->step_over_calls == STEP_OVER_UNDEBUGGABLE
+ || ecs->event_thread->step_over_calls == STEP_OVER_ALL)
+ && get_frame_type (frame) == SIGTRAMP_FRAME)
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: stepped into signal trampoline\n");
NOTE: frame_id_eq will never report two invalid frame IDs as
being equal, so to get into this block, both the current and
previous frame must have valid frame IDs. */
- if (!frame_id_eq (get_frame_id (get_current_frame ()), step_frame_id)
- && frame_id_eq (frame_unwind_id (get_current_frame ()), step_frame_id))
+ if (!frame_id_eq (get_stack_frame_id (frame),
+ ecs->event_thread->step_stack_frame_id)
+ && (frame_id_eq (frame_unwind_caller_id (frame),
+ ecs->event_thread->step_stack_frame_id)
+ || execution_direction == EXEC_REVERSE))
{
CORE_ADDR real_stop_pc;
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: stepped into subroutine\n");
- if ((step_over_calls == STEP_OVER_NONE)
- || ((step_range_end == 1)
- && in_prologue (prev_pc, ecs->stop_func_start)))
+ if ((ecs->event_thread->step_over_calls == STEP_OVER_NONE)
+ || ((ecs->event_thread->step_range_end == 1)
+ && in_prologue (gdbarch, ecs->event_thread->prev_pc,
+ ecs->stop_func_start)))
{
/* I presume that step_over_calls is only 0 when we're
supposed to be stepping at the assembly language level
/* Also, maybe we just did a "nexti" inside a prolog, so we
thought it was a subroutine call but it was not. Stop as
well. FENN */
- stop_step = 1;
+ /* And this works the same backward as frontward. MVS */
+ ecs->event_thread->stop_step = 1;
print_stop_reason (END_STEPPING_RANGE, 0);
stop_stepping (ecs);
return;
}
- if (step_over_calls == STEP_OVER_ALL)
+ /* Reverse stepping through solib trampolines. */
+
+ if (execution_direction == EXEC_REVERSE
+ && (gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc)
+ || (ecs->stop_func_start == 0
+ && in_solib_dynsym_resolve_code (stop_pc))))
+ {
+ /* Any solib trampoline code can be handled in reverse
+ by simply continuing to single-step. We have already
+ executed the solib function (backwards), and a few
+ steps will take us back through the trampoline to the
+ caller. */
+ keep_going (ecs);
+ return;
+ }
+
+ if (ecs->event_thread->step_over_calls == STEP_OVER_ALL)
{
- /* We're doing a "next", set a breakpoint at callee's return
- address (the address at which the caller will
- resume). */
- insert_step_resume_breakpoint_at_caller (get_current_frame ());
+ /* We're doing a "next".
+
+ Normal (forward) execution: set a breakpoint at the
+ callee's return address (the address at which the caller
+ will resume).
+
+ Reverse (backward) execution. set the step-resume
+ breakpoint at the start of the function that we just
+ stepped into (backwards), and continue to there. When we
+ get there, we'll need to single-step back to the caller. */
+
+ if (execution_direction == EXEC_REVERSE)
+ {
+ struct symtab_and_line sr_sal;
+
+ /* Normal function call return (static or dynamic). */
+ init_sal (&sr_sal);
+ sr_sal.pc = ecs->stop_func_start;
+ insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
+ }
+ else
+ insert_step_resume_breakpoint_at_caller (frame);
+
keep_going (ecs);
return;
}
function. That's what tells us (a) whether we want to step
into it at all, and (b) what prologue we want to run to the
end of, if we do step into it. */
- real_stop_pc = skip_language_trampoline (stop_pc);
+ real_stop_pc = skip_language_trampoline (frame, stop_pc);
if (real_stop_pc == 0)
- real_stop_pc = SKIP_TRAMPOLINE_CODE (stop_pc);
+ real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc);
if (real_stop_pc != 0)
ecs->stop_func_start = real_stop_pc;
- if (
-#ifdef IN_SOLIB_DYNSYM_RESOLVE_CODE
- IN_SOLIB_DYNSYM_RESOLVE_CODE (ecs->stop_func_start)
-#else
- in_solib_dynsym_resolve_code (ecs->stop_func_start)
-#endif
-)
+ if (real_stop_pc != 0 && in_solib_dynsym_resolve_code (real_stop_pc))
{
struct symtab_and_line sr_sal;
init_sal (&sr_sal);
tmp_sal = find_pc_line (ecs->stop_func_start, 0);
if (tmp_sal.line != 0)
{
- step_into_function (ecs);
+ if (execution_direction == EXEC_REVERSE)
+ handle_step_into_function_backward (gdbarch, ecs);
+ else
+ handle_step_into_function (gdbarch, ecs);
return;
}
}
/* If we have no line number and the step-stop-if-no-debug is
set, we stop the step so that the user has a chance to switch
in assembly mode. */
- if (step_over_calls == STEP_OVER_UNDEBUGGABLE && step_stop_if_no_debug)
+ if (ecs->event_thread->step_over_calls == STEP_OVER_UNDEBUGGABLE
+ && step_stop_if_no_debug)
{
- stop_step = 1;
+ ecs->event_thread->stop_step = 1;
print_stop_reason (END_STEPPING_RANGE, 0);
stop_stepping (ecs);
return;
}
- /* Set a breakpoint at callee's return address (the address at
- which the caller will resume). */
- insert_step_resume_breakpoint_at_caller (get_current_frame ());
+ if (execution_direction == EXEC_REVERSE)
+ {
+ /* Set a breakpoint at callee's start address.
+ From there we can step once and be back in the caller. */
+ struct symtab_and_line sr_sal;
+ init_sal (&sr_sal);
+ sr_sal.pc = ecs->stop_func_start;
+ insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
+ }
+ else
+ /* Set a breakpoint at callee's return address (the address
+ at which the caller will resume). */
+ insert_step_resume_breakpoint_at_caller (frame);
+
keep_going (ecs);
return;
}
/* If we're in the return path from a shared library trampoline,
we want to proceed through the trampoline when stepping. */
- if (IN_SOLIB_RETURN_TRAMPOLINE (stop_pc, ecs->stop_func_name))
+ if (gdbarch_in_solib_return_trampoline (gdbarch,
+ stop_pc, ecs->stop_func_name))
{
/* Determine where this trampoline returns. */
- CORE_ADDR real_stop_pc = SKIP_TRAMPOLINE_CODE (stop_pc);
+ CORE_ADDR real_stop_pc;
+ real_stop_pc = gdbarch_skip_trampoline_code (gdbarch, frame, stop_pc);
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: stepped into solib return tramp\n");
}
}
- ecs->sal = find_pc_line (stop_pc, 0);
+ stop_pc_sal = find_pc_line (stop_pc, 0);
/* NOTE: tausq/2004-05-24: This if block used to be done before all
the trampoline processing logic, however, there are some trampolines
that have no names, so we should do trampoline handling first. */
- if (step_over_calls == STEP_OVER_UNDEBUGGABLE
+ if (ecs->event_thread->step_over_calls == STEP_OVER_UNDEBUGGABLE
&& ecs->stop_func_name == NULL
- && ecs->sal.line == 0)
+ && stop_pc_sal.line == 0)
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: stepped into undebuggable function\n");
set step-mode) or we no longer know how to get back
to the call site. */
if (step_stop_if_no_debug
- || !frame_id_p (frame_unwind_id (get_current_frame ())))
+ || !frame_id_p (frame_unwind_caller_id (frame)))
{
/* If we have no line number and the step-stop-if-no-debug
is set, we stop the step so that the user has a chance to
switch in assembly mode. */
- stop_step = 1;
+ ecs->event_thread->stop_step = 1;
print_stop_reason (END_STEPPING_RANGE, 0);
stop_stepping (ecs);
return;
{
/* Set a breakpoint at callee's return address (the address
at which the caller will resume). */
- insert_step_resume_breakpoint_at_caller (get_current_frame ());
+ insert_step_resume_breakpoint_at_caller (frame);
keep_going (ecs);
return;
}
}
- if (step_range_end == 1)
+ if (ecs->event_thread->step_range_end == 1)
{
/* It is stepi or nexti. We always want to stop stepping after
one instruction. */
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: stepi/nexti\n");
- stop_step = 1;
+ ecs->event_thread->stop_step = 1;
print_stop_reason (END_STEPPING_RANGE, 0);
stop_stepping (ecs);
return;
}
- if (ecs->sal.line == 0)
+ if (stop_pc_sal.line == 0)
{
/* We have no line number information. That means to stop
stepping (does this always happen right after one instruction,
or can this happen as a result of a return or longjmp?). */
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: no line number info\n");
- stop_step = 1;
+ ecs->event_thread->stop_step = 1;
print_stop_reason (END_STEPPING_RANGE, 0);
stop_stepping (ecs);
return;
}
- if ((stop_pc == ecs->sal.pc)
- && (ecs->current_line != ecs->sal.line
- || ecs->current_symtab != ecs->sal.symtab))
+ /* Look for "calls" to inlined functions, part one. If the inline
+ frame machinery detected some skipped call sites, we have entered
+ a new inline function. */
+
+ if (frame_id_eq (get_frame_id (get_current_frame ()),
+ ecs->event_thread->step_frame_id)
+ && inline_skipped_frames (ecs->ptid))
+ {
+ struct symtab_and_line call_sal;
+
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: stepped into inlined function\n");
+
+ find_frame_sal (get_current_frame (), &call_sal);
+
+ if (ecs->event_thread->step_over_calls != STEP_OVER_ALL)
+ {
+ /* For "step", we're going to stop. But if the call site
+ for this inlined function is on the same source line as
+ we were previously stepping, go down into the function
+ first. Otherwise stop at the call site. */
+
+ if (call_sal.line == ecs->event_thread->current_line
+ && call_sal.symtab == ecs->event_thread->current_symtab)
+ step_into_inline_frame (ecs->ptid);
+
+ ecs->event_thread->stop_step = 1;
+ print_stop_reason (END_STEPPING_RANGE, 0);
+ stop_stepping (ecs);
+ return;
+ }
+ else
+ {
+ /* For "next", we should stop at the call site if it is on a
+ different source line. Otherwise continue through the
+ inlined function. */
+ if (call_sal.line == ecs->event_thread->current_line
+ && call_sal.symtab == ecs->event_thread->current_symtab)
+ keep_going (ecs);
+ else
+ {
+ ecs->event_thread->stop_step = 1;
+ print_stop_reason (END_STEPPING_RANGE, 0);
+ stop_stepping (ecs);
+ }
+ return;
+ }
+ }
+
+ /* Look for "calls" to inlined functions, part two. If we are still
+ in the same real function we were stepping through, but we have
+ to go further up to find the exact frame ID, we are stepping
+ through a more inlined call beyond its call site. */
+
+ if (get_frame_type (get_current_frame ()) == INLINE_FRAME
+ && !frame_id_eq (get_frame_id (get_current_frame ()),
+ ecs->event_thread->step_frame_id)
+ && stepped_in_from (get_current_frame (),
+ ecs->event_thread->step_frame_id))
+ {
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: stepping through inlined function\n");
+
+ if (ecs->event_thread->step_over_calls == STEP_OVER_ALL)
+ keep_going (ecs);
+ else
+ {
+ ecs->event_thread->stop_step = 1;
+ print_stop_reason (END_STEPPING_RANGE, 0);
+ stop_stepping (ecs);
+ }
+ return;
+ }
+
+ if ((stop_pc == stop_pc_sal.pc)
+ && (ecs->event_thread->current_line != stop_pc_sal.line
+ || ecs->event_thread->current_symtab != stop_pc_sal.symtab))
{
/* We are at the start of a different line. So stop. Note that
we don't stop if we step into the middle of a different line.
better. */
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: stepped to a different line\n");
- stop_step = 1;
+ ecs->event_thread->stop_step = 1;
print_stop_reason (END_STEPPING_RANGE, 0);
stop_stepping (ecs);
return;
new line in mid-statement, we continue stepping. This makes
things like for(;;) statements work better.) */
- if (ecs->stop_func_end && ecs->sal.end >= ecs->stop_func_end)
- {
- /* If this is the last line of the function, don't keep stepping
- (it would probably step us out of the function).
- This is particularly necessary for a one-line function,
- in which after skipping the prologue we better stop even though
- we will be in mid-line. */
- if (debug_infrun)
- fprintf_unfiltered (gdb_stdlog, "infrun: stepped to a different function\n");
- stop_step = 1;
- print_stop_reason (END_STEPPING_RANGE, 0);
- stop_stepping (ecs);
- return;
- }
- step_range_start = ecs->sal.pc;
- step_range_end = ecs->sal.end;
- step_frame_id = get_frame_id (get_current_frame ());
- ecs->current_line = ecs->sal.line;
- ecs->current_symtab = ecs->sal.symtab;
-
- /* In the case where we just stepped out of a function into the
- middle of a line of the caller, continue stepping, but
- step_frame_id must be modified to current frame */
-#if 0
- /* NOTE: cagney/2003-10-16: I think this frame ID inner test is too
- generous. It will trigger on things like a step into a frameless
- stackless leaf function. I think the logic should instead look
- at the unwound frame ID has that should give a more robust
- indication of what happened. */
- if (step - ID == current - ID)
- still stepping in same function;
- else if (step - ID == unwind (current - ID))
- stepped into a function;
- else
- stepped out of a function;
- /* Of course this assumes that the frame ID unwind code is robust
- and we're willing to introduce frame unwind logic into this
- function. Fortunately, those days are nearly upon us. */
-#endif
- {
- struct frame_id current_frame = get_frame_id (get_current_frame ());
- if (!(frame_id_inner (current_frame, step_frame_id)))
- step_frame_id = current_frame;
- }
+ ecs->event_thread->step_range_start = stop_pc_sal.pc;
+ ecs->event_thread->step_range_end = stop_pc_sal.end;
+ set_step_info (frame, stop_pc_sal);
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: keep going\n");
keep_going (ecs);
}
-/* Are we in the middle of stepping? */
+/* Is thread TP in the middle of single-stepping? */
+
+static int
+currently_stepping (struct thread_info *tp)
+{
+ return ((tp->step_range_end && tp->step_resume_breakpoint == NULL)
+ || tp->trap_expected
+ || tp->stepping_through_solib_after_catch
+ || bpstat_should_step ());
+}
+
+/* Returns true if any thread *but* the one passed in "data" is in the
+ middle of stepping or of handling a "next". */
static int
-currently_stepping (struct execution_control_state *ecs)
+currently_stepping_or_nexting_callback (struct thread_info *tp, void *data)
{
- return ((!ecs->handling_longjmp
- && ((step_range_end && step_resume_breakpoint == NULL)
- || trap_expected))
- || ecs->stepping_through_solib_after_catch
- || bpstat_should_step ());
+ if (tp == data)
+ return 0;
+
+ return (tp->step_range_end
+ || tp->trap_expected
+ || tp->stepping_through_solib_after_catch);
}
-/* Subroutine call with source code we should not step over. Do step
- to the first line of code in it. */
+/* Inferior has stepped into a subroutine call with source code that
+ we should not step over. Do step to the first line of code in
+ it. */
static void
-step_into_function (struct execution_control_state *ecs)
+handle_step_into_function (struct gdbarch *gdbarch,
+ struct execution_control_state *ecs)
{
struct symtab *s;
- struct symtab_and_line sr_sal;
+ struct symtab_and_line stop_func_sal, sr_sal;
s = find_pc_symtab (stop_pc);
if (s && s->language != language_asm)
- ecs->stop_func_start = SKIP_PROLOGUE (ecs->stop_func_start);
+ ecs->stop_func_start = gdbarch_skip_prologue (gdbarch,
+ ecs->stop_func_start);
- ecs->sal = find_pc_line (ecs->stop_func_start, 0);
+ stop_func_sal = find_pc_line (ecs->stop_func_start, 0);
/* Use the step_resume_break to step until the end of the prologue,
even if that involves jumps (as it seems to on the vax under
4.2). */
/* If the prologue ends in the middle of a source line, continue to
the end of that source line (if it is still within the function).
Otherwise, just go to end of prologue. */
- if (ecs->sal.end
- && ecs->sal.pc != ecs->stop_func_start
- && ecs->sal.end < ecs->stop_func_end)
- ecs->stop_func_start = ecs->sal.end;
+ if (stop_func_sal.end
+ && stop_func_sal.pc != ecs->stop_func_start
+ && stop_func_sal.end < ecs->stop_func_end)
+ ecs->stop_func_start = stop_func_sal.end;
/* Architectures which require breakpoint adjustment might not be able
to place a breakpoint at the computed address. If so, the test
the VLIW instruction. Thus, we need to make the corresponding
adjustment here when computing the stop address. */
- if (gdbarch_adjust_breakpoint_address_p (current_gdbarch))
+ if (gdbarch_adjust_breakpoint_address_p (gdbarch))
{
ecs->stop_func_start
- = gdbarch_adjust_breakpoint_address (current_gdbarch,
+ = gdbarch_adjust_breakpoint_address (gdbarch,
ecs->stop_func_start);
}
if (ecs->stop_func_start == stop_pc)
{
/* We are already there: stop now. */
- stop_step = 1;
+ ecs->event_thread->stop_step = 1;
print_stop_reason (END_STEPPING_RANGE, 0);
stop_stepping (ecs);
return;
insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
/* And make sure stepping stops right away then. */
- step_range_end = step_range_start;
+ ecs->event_thread->step_range_end = ecs->event_thread->step_range_start;
}
keep_going (ecs);
}
-/* Insert a "step resume breakpoint" at SR_SAL with frame ID SR_ID.
+/* Inferior has stepped backward into a subroutine call with source
+ code that we should not step over. Do step to the beginning of the
+ last line of code in it. */
+
+static void
+handle_step_into_function_backward (struct gdbarch *gdbarch,
+ struct execution_control_state *ecs)
+{
+ struct symtab *s;
+ struct symtab_and_line stop_func_sal, sr_sal;
+
+ s = find_pc_symtab (stop_pc);
+ if (s && s->language != language_asm)
+ ecs->stop_func_start = gdbarch_skip_prologue (gdbarch,
+ ecs->stop_func_start);
+
+ stop_func_sal = find_pc_line (stop_pc, 0);
+
+ /* OK, we're just going to keep stepping here. */
+ if (stop_func_sal.pc == stop_pc)
+ {
+ /* We're there already. Just stop stepping now. */
+ ecs->event_thread->stop_step = 1;
+ print_stop_reason (END_STEPPING_RANGE, 0);
+ stop_stepping (ecs);
+ }
+ else
+ {
+ /* Else just reset the step range and keep going.
+ No step-resume breakpoint, they don't work for
+ epilogues, which can have multiple entry paths. */
+ ecs->event_thread->step_range_start = stop_func_sal.pc;
+ ecs->event_thread->step_range_end = stop_func_sal.end;
+ keep_going (ecs);
+ }
+ return;
+}
+
+/* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
This is used to both functions and to skip over code. */
static void
insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal,
struct frame_id sr_id)
{
- /* There should never be more than one step-resume breakpoint per
- thread, so we should never be setting a new
+ /* There should never be more than one step-resume or longjmp-resume
+ breakpoint per thread, so we should never be setting a new
step_resume_breakpoint when one is already active. */
- gdb_assert (step_resume_breakpoint == NULL);
- step_resume_breakpoint = set_momentary_breakpoint (sr_sal, sr_id,
- bp_step_resume);
- if (breakpoints_inserted)
- insert_breakpoints ();
+ gdb_assert (inferior_thread ()->step_resume_breakpoint == NULL);
+
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: inserting step-resume breakpoint at 0x%s\n",
+ paddr_nz (sr_sal.pc));
+
+ inferior_thread ()->step_resume_breakpoint
+ = set_momentary_breakpoint (sr_sal, sr_id, bp_step_resume);
}
-/* Insert a "step resume breakpoint" at RETURN_FRAME.pc. This is used
+/* Insert a "step-resume breakpoint" at RETURN_FRAME.pc. This is used
to skip a potential signal handler.
This is called with the interrupted function's frame. The signal
static void
insert_step_resume_breakpoint_at_frame (struct frame_info *return_frame)
{
+ struct gdbarch *gdbarch = get_frame_arch (return_frame);
struct symtab_and_line sr_sal;
+ gdb_assert (return_frame != NULL);
init_sal (&sr_sal); /* initialize to zeros */
- sr_sal.pc = ADDR_BITS_REMOVE (get_frame_pc (return_frame));
+ sr_sal.pc = gdbarch_addr_bits_remove (gdbarch, get_frame_pc (return_frame));
sr_sal.section = find_pc_overlay (sr_sal.pc);
- insert_step_resume_breakpoint_at_sal (sr_sal, get_frame_id (return_frame));
+ insert_step_resume_breakpoint_at_sal (sr_sal, get_stack_frame_id (return_frame));
}
/* Similar to insert_step_resume_breakpoint_at_frame, except
This is a separate function rather than reusing
insert_step_resume_breakpoint_at_frame in order to avoid
get_prev_frame, which may stop prematurely (see the implementation
- of frame_unwind_id for an example). */
+ of frame_unwind_caller_id for an example). */
static void
insert_step_resume_breakpoint_at_caller (struct frame_info *next_frame)
{
+ struct gdbarch *gdbarch = get_frame_arch (next_frame);
struct symtab_and_line sr_sal;
/* We shouldn't have gotten here if we don't know where the call site
is. */
- gdb_assert (frame_id_p (frame_unwind_id (next_frame)));
+ gdb_assert (frame_id_p (frame_unwind_caller_id (next_frame)));
init_sal (&sr_sal); /* initialize to zeros */
- sr_sal.pc = ADDR_BITS_REMOVE (frame_pc_unwind (next_frame));
+ sr_sal.pc = gdbarch_addr_bits_remove (gdbarch,
+ frame_unwind_caller_pc (next_frame));
sr_sal.section = find_pc_overlay (sr_sal.pc);
- insert_step_resume_breakpoint_at_sal (sr_sal, frame_unwind_id (next_frame));
+ insert_step_resume_breakpoint_at_sal (sr_sal,
+ frame_unwind_caller_id (next_frame));
+}
+
+/* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
+ new breakpoint at the target of a jmp_buf. The handling of
+ longjmp-resume uses the same mechanisms used for handling
+ "step-resume" breakpoints. */
+
+static void
+insert_longjmp_resume_breakpoint (CORE_ADDR pc)
+{
+ /* There should never be more than one step-resume or longjmp-resume
+ breakpoint per thread, so we should never be setting a new
+ longjmp_resume_breakpoint when one is already active. */
+ gdb_assert (inferior_thread ()->step_resume_breakpoint == NULL);
+
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: inserting longjmp-resume breakpoint at 0x%s\n",
+ paddr_nz (pc));
+
+ inferior_thread ()->step_resume_breakpoint =
+ set_momentary_breakpoint_at_pc (pc, bp_longjmp_resume);
}
static void
keep_going (struct execution_control_state *ecs)
{
/* Save the pc before execution, to compare with pc after stop. */
- prev_pc = read_pc (); /* Might have been DECR_AFTER_BREAK */
+ ecs->event_thread->prev_pc
+ = regcache_read_pc (get_thread_regcache (ecs->ptid));
/* If we did not do break;, it means we should keep running the
inferior and not return to debugger. */
- if (trap_expected && stop_signal != TARGET_SIGNAL_TRAP)
+ if (ecs->event_thread->trap_expected
+ && ecs->event_thread->stop_signal != TARGET_SIGNAL_TRAP)
{
/* We took a signal (which we are supposed to pass through to
- the inferior, else we'd have done a break above) and we
- haven't yet gotten our trap. Simply continue. */
- resume (currently_stepping (ecs), stop_signal);
+ the inferior, else we'd not get here) and we haven't yet
+ gotten our trap. Simply continue. */
+ resume (currently_stepping (ecs->event_thread),
+ ecs->event_thread->stop_signal);
}
else
{
The signal was SIGTRAP, e.g. it was our signal, but we
decided we should resume from it.
- We're going to run this baby now! */
+ We're going to run this baby now!
- if (!breakpoints_inserted && !ecs->another_trap)
+ Note that insert_breakpoints won't try to re-insert
+ already inserted breakpoints. Therefore, we don't
+ care if breakpoints were already inserted, or not. */
+
+ if (ecs->event_thread->stepping_over_breakpoint)
+ {
+ struct regcache *thread_regcache = get_thread_regcache (ecs->ptid);
+ if (!use_displaced_stepping (get_regcache_arch (thread_regcache)))
+ /* Since we can't do a displaced step, we have to remove
+ the breakpoint while we step it. To keep things
+ simple, we remove them all. */
+ remove_breakpoints ();
+ }
+ else
{
- breakpoints_failed = insert_breakpoints ();
- if (breakpoints_failed)
+ struct gdb_exception e;
+ /* Stop stepping when inserting breakpoints
+ has failed. */
+ TRY_CATCH (e, RETURN_MASK_ERROR)
+ {
+ insert_breakpoints ();
+ }
+ if (e.reason < 0)
{
stop_stepping (ecs);
return;
}
- breakpoints_inserted = 1;
}
- trap_expected = ecs->another_trap;
+ ecs->event_thread->trap_expected = ecs->event_thread->stepping_over_breakpoint;
/* Do not deliver SIGNAL_TRAP (except when the user explicitly
specifies that such a signal should be delivered to the
simulator; the simulator then delivers the hardware
equivalent of a SIGNAL_TRAP to the program being debugged. */
- if (stop_signal == TARGET_SIGNAL_TRAP && !signal_program[stop_signal])
- stop_signal = TARGET_SIGNAL_0;
+ if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP
+ && !signal_program[ecs->event_thread->stop_signal])
+ ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
-
- resume (currently_stepping (ecs), stop_signal);
+ resume (currently_stepping (ecs->event_thread),
+ ecs->event_thread->stop_signal);
}
prepare_to_wait (ecs);
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: prepare_to_wait\n");
- if (ecs->infwait_state == infwait_normal_state)
+ if (infwait_state == infwait_normal_state)
{
overlay_cache_invalid = 1;
as part of their normal status mechanism. */
registers_changed ();
- ecs->waiton_ptid = pid_to_ptid (-1);
- ecs->wp = &(ecs->ws);
+ waiton_ptid = pid_to_ptid (-1);
}
/* This is the old end of the while loop. Let everybody know we
want to wait for the inferior some more and get called again
{
switch (stop_reason)
{
- case STOP_UNKNOWN:
- /* We don't deal with these cases from handle_inferior_event()
- yet. */
- break;
case END_STEPPING_RANGE:
/* We are done with a step/next/si/ni command. */
/* For now print nothing. */
/* Print a message only if not in the middle of doing a "step n"
operation for n > 1 */
- if (!step_multi || !stop_step)
+ if (!inferior_thread ()->step_multi
+ || !inferior_thread ()->stop_step)
if (ui_out_is_mi_like_p (uiout))
ui_out_field_string
(uiout, "reason",
async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE));
break;
- case BREAKPOINT_HIT:
- /* We found a breakpoint. */
- /* For now print nothing. */
- break;
case SIGNAL_EXITED:
/* The inferior was terminated by a signal. */
annotate_signalled ();
return_child_result_value = stop_info;
break;
case SIGNAL_RECEIVED:
- /* Signal received. The signal table tells us to print about
- it. */
+ /* Signal received. The signal table tells us to print about
+ it. */
annotate_signal ();
- ui_out_text (uiout, "\nProgram received signal ");
- annotate_signal_name ();
- if (ui_out_is_mi_like_p (uiout))
- ui_out_field_string
- (uiout, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED));
- ui_out_field_string (uiout, "signal-name",
- target_signal_to_name (stop_info));
- annotate_signal_name_end ();
- ui_out_text (uiout, ", ");
- annotate_signal_string ();
- ui_out_field_string (uiout, "signal-meaning",
- target_signal_to_string (stop_info));
- annotate_signal_string_end ();
+
+ if (stop_info == TARGET_SIGNAL_0 && !ui_out_is_mi_like_p (uiout))
+ {
+ struct thread_info *t = inferior_thread ();
+
+ ui_out_text (uiout, "\n[");
+ ui_out_field_string (uiout, "thread-name",
+ target_pid_to_str (t->ptid));
+ ui_out_field_fmt (uiout, "thread-id", "] #%d", t->num);
+ ui_out_text (uiout, " stopped");
+ }
+ else
+ {
+ ui_out_text (uiout, "\nProgram received signal ");
+ annotate_signal_name ();
+ if (ui_out_is_mi_like_p (uiout))
+ ui_out_field_string
+ (uiout, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED));
+ ui_out_field_string (uiout, "signal-name",
+ target_signal_to_name (stop_info));
+ annotate_signal_name_end ();
+ ui_out_text (uiout, ", ");
+ annotate_signal_string ();
+ ui_out_field_string (uiout, "signal-meaning",
+ target_signal_to_string (stop_info));
+ annotate_signal_string_end ();
+ }
ui_out_text (uiout, ".\n");
break;
+ case NO_HISTORY:
+ /* Reverse execution: target ran out of history info. */
+ ui_out_text (uiout, "\nNo more reverse-execution history.\n");
+ break;
default:
internal_error (__FILE__, __LINE__,
_("print_stop_reason: unrecognized enum value"));
{
struct target_waitstatus last;
ptid_t last_ptid;
+ struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
get_last_target_status (&last_ptid, &last);
+ /* If an exception is thrown from this point on, make sure to
+ propagate GDB's knowledge of the executing state to the
+ frontend/user running state. A QUIT is an easy exception to see
+ here, so do this before any filtered output. */
+ if (!non_stop)
+ make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
+ else if (last.kind != TARGET_WAITKIND_SIGNALLED
+ && last.kind != TARGET_WAITKIND_EXITED)
+ make_cleanup (finish_thread_state_cleanup, &inferior_ptid);
+
+ /* In non-stop mode, we don't want GDB to switch threads behind the
+ user's back, to avoid races where the user is typing a command to
+ apply to thread x, but GDB switches to thread y before the user
+ finishes entering the command. */
+
/* As with the notification of thread events, we want to delay
notifying the user that we've switched thread context until
the inferior actually stops.
There's no point in saying anything if the inferior has exited.
Note that SIGNALLED here means "exited with a signal", not
"received a signal". */
- if (!ptid_equal (previous_inferior_ptid, inferior_ptid)
+ if (!non_stop
+ && !ptid_equal (previous_inferior_ptid, inferior_ptid)
&& target_has_execution
&& last.kind != TARGET_WAITKIND_SIGNALLED
&& last.kind != TARGET_WAITKIND_EXITED)
{
target_terminal_ours_for_output ();
printf_filtered (_("[Switching to %s]\n"),
- target_pid_or_tid_to_str (inferior_ptid));
+ target_pid_to_str (inferior_ptid));
+ annotate_thread_changed ();
previous_inferior_ptid = inferior_ptid;
}
- /* NOTE drow/2004-01-17: Is this still necessary? */
- /* Make sure that the current_frame's pc is correct. This
- is a correction for setting up the frame info before doing
- DECR_PC_AFTER_BREAK */
- if (target_has_execution)
- /* FIXME: cagney/2002-12-06: Has the PC changed? Thanks to
- DECR_PC_AFTER_BREAK, the program counter can change. Ask the
- frame code to check for this and sort out any resultant mess.
- DECR_PC_AFTER_BREAK needs to just go away. */
- deprecated_update_frame_pc_hack (get_current_frame (), read_pc ());
-
- if (target_has_execution && breakpoints_inserted)
+ if (!breakpoints_always_inserted_mode () && target_has_execution)
{
if (remove_breakpoints ())
{
target_terminal_ours_for_output ();
printf_filtered (_("\
Cannot remove breakpoints because program is no longer writable.\n\
-It might be running in another process.\n\
Further execution is probably impossible.\n"));
}
}
- breakpoints_inserted = 0;
-
- /* Delete the breakpoint we stopped at, if it wants to be deleted.
- Delete any breakpoint that is to be deleted at the next stop. */
-
- breakpoint_auto_delete (stop_bpstat);
/* If an auto-display called a function and that got a signal,
delete that auto-display to avoid an infinite recursion. */
/* Don't print a message if in the middle of doing a "step n"
operation for n > 1 */
- if (step_multi && stop_step)
+ if (target_has_execution
+ && last.kind != TARGET_WAITKIND_SIGNALLED
+ && last.kind != TARGET_WAITKIND_EXITED
+ && inferior_thread ()->step_multi
+ && inferior_thread ()->stop_step)
goto done;
target_terminal_ours ();
/* Set the current source location. This will also happen if we
display the frame below, but the current SAL will be incorrect
during a user hook-stop function. */
- if (target_has_stack && !stop_stack_dummy)
+ if (has_stack_frames () && !stop_stack_dummy)
set_current_sal_from_frame (get_current_frame (), 1);
+ /* Let the user/frontend see the threads as stopped. */
+ do_cleanups (old_chain);
+
/* Look up the hook_stop and run it (CLI internally handles problem
of stop_command's pre-hook not existing). */
if (stop_command)
catch_errors (hook_stop_stub, stop_command,
"Error while running hook_stop:\n", RETURN_MASK_ALL);
- if (!target_has_stack)
- {
+ if (!has_stack_frames ())
+ goto done;
- goto done;
- }
+ if (last.kind == TARGET_WAITKIND_SIGNALLED
+ || last.kind == TARGET_WAITKIND_EXITED)
+ goto done;
/* Select innermost stack frame - i.e., current frame is frame 0,
and current location is based on that.
bpstat_print() contains the logic deciding in detail
what to print, based on the event(s) that just occurred. */
- if (stop_print_frame && deprecated_selected_frame)
+ /* If --batch-silent is enabled then there's no need to print the current
+ source location, and to try risks causing an error message about
+ missing source files. */
+ if (stop_print_frame && !batch_silent)
{
int bpstat_ret;
int source_flag;
int do_frame_printing = 1;
+ struct thread_info *tp = inferior_thread ();
- bpstat_ret = bpstat_print (stop_bpstat);
+ bpstat_ret = bpstat_print (tp->stop_bpstat);
switch (bpstat_ret)
{
case PRINT_UNKNOWN:
+ /* If we had hit a shared library event breakpoint,
+ bpstat_print would print out this message. If we hit
+ an OS-level shared library event, do the same
+ thing. */
+ if (last.kind == TARGET_WAITKIND_LOADED)
+ {
+ printf_filtered (_("Stopped due to shared library event\n"));
+ source_flag = SRC_LINE; /* something bogus */
+ do_frame_printing = 0;
+ break;
+ }
+
/* FIXME: cagney/2002-12-01: Given that a frame ID does
(or should) carry around the function and does (or
should) use that when doing a frame comparison. */
- if (stop_step
- && frame_id_eq (step_frame_id,
+ if (tp->stop_step
+ && frame_id_eq (tp->step_frame_id,
get_frame_id (get_current_frame ()))
&& step_start_function == find_pc_function (stop_pc))
source_flag = SRC_LINE; /* finished step, just print source line */
default:
internal_error (__FILE__, __LINE__, _("Unknown value."));
}
- /* For mi, have the same behavior every time we stop:
- print everything but the source line. */
- if (ui_out_is_mi_like_p (uiout))
- source_flag = LOC_AND_ADDRESS;
- if (ui_out_is_mi_like_p (uiout))
- ui_out_field_int (uiout, "thread-id",
- pid_to_thread_id (inferior_ptid));
/* The behavior of this routine with respect to the source
flag is:
SRC_LINE: Print only source line
/* Save the function value return registers, if we care.
We might be about to restore their previous contents. */
- if (proceed_to_finish)
- /* NB: The copy goes through to the target picking up the value of
- all the registers. */
- regcache_cpy (stop_registers, current_regcache);
+ if (inferior_thread ()->proceed_to_finish)
+ {
+ /* This should not be necessary. */
+ if (stop_registers)
+ regcache_xfree (stop_registers);
+
+ /* NB: The copy goes through to the target picking up the value of
+ all the registers. */
+ stop_registers = regcache_dup (get_current_regcache ());
+ }
if (stop_stack_dummy)
{
- /* Pop the empty frame that contains the stack dummy. POP_FRAME
- ends with a setting of the current frame, so we can use that
- next. */
- frame_pop (get_current_frame ());
- /* Set stop_pc to what it was before we called the function.
- Can't rely on restore_inferior_status because that only gets
- called if we don't stop in the called function. */
- stop_pc = read_pc ();
+ /* Pop the empty frame that contains the stack dummy.
+ This also restores inferior state prior to the call
+ (struct inferior_thread_state). */
+ struct frame_info *frame = get_current_frame ();
+ gdb_assert (get_frame_type (frame) == DUMMY_FRAME);
+ frame_pop (frame);
+ /* frame_pop() calls reinit_frame_cache as the last thing it does
+ which means there's currently no selected frame. We don't need
+ to re-establish a selected frame if the dummy call returns normally,
+ that will be done by restore_inferior_status. However, we do have
+ to handle the case where the dummy call is returning after being
+ stopped (e.g. the dummy call previously hit a breakpoint). We
+ can't know which case we have so just always re-establish a
+ selected frame here. */
select_frame (get_current_frame ());
}
done:
annotate_stopped ();
- observer_notify_normal_stop (stop_bpstat);
+
+ /* Suppress the stop observer if we're in the middle of:
+
+ - a step n (n > 1), as there still more steps to be done.
+
+ - a "finish" command, as the observer will be called in
+ finish_command_continuation, so it can include the inferior
+ function's return value.
+
+ - calling an inferior function, as we pretend we inferior didn't
+ run at all. The return value of the call is handled by the
+ expression evaluator, through call_function_by_hand. */
+
+ if (!target_has_execution
+ || last.kind == TARGET_WAITKIND_SIGNALLED
+ || last.kind == TARGET_WAITKIND_EXITED
+ || (!inferior_thread ()->step_multi
+ && !(inferior_thread ()->stop_bpstat
+ && inferior_thread ()->proceed_to_finish)
+ && !inferior_thread ()->in_infcall))
+ {
+ if (!ptid_equal (inferior_ptid, null_ptid))
+ observer_notify_normal_stop (inferior_thread ()->stop_bpstat,
+ stop_print_frame);
+ else
+ observer_notify_normal_stop (NULL, stop_print_frame);
+ }
+
+ if (target_has_execution)
+ {
+ if (last.kind != TARGET_WAITKIND_SIGNALLED
+ && last.kind != TARGET_WAITKIND_EXITED)
+ /* Delete the breakpoint we stopped at, if it wants to be deleted.
+ Delete any breakpoint that is to be deleted at the next stop. */
+ breakpoint_auto_delete (inferior_thread ()->stop_bpstat);
+ }
}
static int
static void
sig_print_info (enum target_signal oursig)
{
- char *name = target_signal_to_name (oursig);
+ const char *name = target_signal_to_name (oursig);
int name_padding = 13 - strlen (name);
if (name_padding <= 0)
/* Break the command line up into args. */
- argv = buildargv (args);
- if (argv == NULL)
- {
- nomem (0);
- }
+ argv = gdb_buildargv (args);
old_chain = make_cleanup_freeargv (argv);
/* Walk through the args, looking for signal oursigs, signal names, and
case TARGET_SIGNAL_INT:
if (!allsigs && !sigs[signum])
{
- if (query ("%s is used by the debugger.\n\
-Are you sure you want to change it? ", target_signal_to_name ((enum target_signal) signum)))
+ if (query (_("%s is used by the debugger.\n\
+Are you sure you want to change it? "), target_signal_to_name ((enum target_signal) signum)))
{
sigs[signum] = 1;
}
argv++;
}
- target_notice_signals (inferior_ptid);
+ for (signum = 0; signum < nsigs; signum++)
+ if (sigs[signum])
+ {
+ target_notice_signals (inferior_ptid);
- if (from_tty)
- {
- /* Show the results. */
- sig_print_header ();
- for (signum = 0; signum < nsigs; signum++)
- {
- if (sigs[signum])
- {
- sig_print_info (signum);
- }
- }
- }
+ if (from_tty)
+ {
+ /* Show the results. */
+ sig_print_header ();
+ for (; signum < nsigs; signum++)
+ if (sigs[signum])
+ sig_print_info (signum);
+ }
+
+ break;
+ }
do_cleanups (old_chain);
}
char **argv;
struct cleanup *old_chain;
+ if (args == NULL)
+ error_no_arg (_("xdb command"));
+
/* Break the command line up into args. */
- argv = buildargv (args);
- if (argv == NULL)
- {
- nomem (0);
- }
+ argv = gdb_buildargv (args);
old_chain = make_cleanup_freeargv (argv);
if (argv[1] != (char *) NULL)
{
printf_filtered (_("\nUse the \"handle\" command to change these tables.\n"));
}
+
+/* The $_siginfo convenience variable is a bit special. We don't know
+ for sure the type of the value until we actually have a chance to
+ fetch the data. The type can change depending on gdbarch, so it it
+ also dependent on which thread you have selected.
+
+ 1. making $_siginfo be an internalvar that creates a new value on
+ access.
+
+ 2. making the value of $_siginfo be an lval_computed value. */
+
+/* This function implements the lval_computed support for reading a
+ $_siginfo value. */
+
+static void
+siginfo_value_read (struct value *v)
+{
+ LONGEST transferred;
+
+ transferred =
+ target_read (¤t_target, TARGET_OBJECT_SIGNAL_INFO,
+ NULL,
+ value_contents_all_raw (v),
+ value_offset (v),
+ TYPE_LENGTH (value_type (v)));
+
+ if (transferred != TYPE_LENGTH (value_type (v)))
+ error (_("Unable to read siginfo"));
+}
+
+/* This function implements the lval_computed support for writing a
+ $_siginfo value. */
+
+static void
+siginfo_value_write (struct value *v, struct value *fromval)
+{
+ LONGEST transferred;
+
+ transferred = target_write (¤t_target,
+ TARGET_OBJECT_SIGNAL_INFO,
+ NULL,
+ value_contents_all_raw (fromval),
+ value_offset (v),
+ TYPE_LENGTH (value_type (fromval)));
+
+ if (transferred != TYPE_LENGTH (value_type (fromval)))
+ error (_("Unable to write siginfo"));
+}
+
+static struct lval_funcs siginfo_value_funcs =
+ {
+ siginfo_value_read,
+ siginfo_value_write
+ };
+
+/* Return a new value with the correct type for the siginfo object of
+ the current thread using architecture GDBARCH. Return a void value
+ if there's no object available. */
+
+static struct value *
+siginfo_make_value (struct gdbarch *gdbarch, struct internalvar *var)
+{
+ if (target_has_stack
+ && !ptid_equal (inferior_ptid, null_ptid)
+ && gdbarch_get_siginfo_type_p (gdbarch))
+ {
+ struct type *type = gdbarch_get_siginfo_type (gdbarch);
+ return allocate_computed_value (type, &siginfo_value_funcs, NULL);
+ }
+
+ return allocate_value (builtin_type (gdbarch)->builtin_void);
+}
+
\f
-struct inferior_status
+/* Inferior thread state.
+ These are details related to the inferior itself, and don't include
+ things like what frame the user had selected or what gdb was doing
+ with the target at the time.
+ For inferior function calls these are things we want to restore
+ regardless of whether the function call successfully completes
+ or the dummy frame has to be manually popped. */
+
+struct inferior_thread_state
{
enum target_signal stop_signal;
CORE_ADDR stop_pc;
+ struct regcache *registers;
+};
+
+struct inferior_thread_state *
+save_inferior_thread_state (void)
+{
+ struct inferior_thread_state *inf_state = XMALLOC (struct inferior_thread_state);
+ struct thread_info *tp = inferior_thread ();
+
+ inf_state->stop_signal = tp->stop_signal;
+ inf_state->stop_pc = stop_pc;
+
+ inf_state->registers = regcache_dup (get_current_regcache ());
+
+ return inf_state;
+}
+
+/* Restore inferior session state to INF_STATE. */
+
+void
+restore_inferior_thread_state (struct inferior_thread_state *inf_state)
+{
+ struct thread_info *tp = inferior_thread ();
+
+ tp->stop_signal = inf_state->stop_signal;
+ stop_pc = inf_state->stop_pc;
+
+ /* The inferior can be gone if the user types "print exit(0)"
+ (and perhaps other times). */
+ if (target_has_execution)
+ /* NB: The register write goes through to the target. */
+ regcache_cpy (get_current_regcache (), inf_state->registers);
+ regcache_xfree (inf_state->registers);
+ xfree (inf_state);
+}
+
+static void
+do_restore_inferior_thread_state_cleanup (void *state)
+{
+ restore_inferior_thread_state (state);
+}
+
+struct cleanup *
+make_cleanup_restore_inferior_thread_state (struct inferior_thread_state *inf_state)
+{
+ return make_cleanup (do_restore_inferior_thread_state_cleanup, inf_state);
+}
+
+void
+discard_inferior_thread_state (struct inferior_thread_state *inf_state)
+{
+ regcache_xfree (inf_state->registers);
+ xfree (inf_state);
+}
+
+struct regcache *
+get_inferior_thread_state_regcache (struct inferior_thread_state *inf_state)
+{
+ return inf_state->registers;
+}
+
+/* Session related state for inferior function calls.
+ These are the additional bits of state that need to be restored
+ when an inferior function call successfully completes. */
+
+struct inferior_status
+{
bpstat stop_bpstat;
int stop_step;
int stop_stack_dummy;
int stopped_by_random_signal;
- int trap_expected;
+ int stepping_over_breakpoint;
CORE_ADDR step_range_start;
CORE_ADDR step_range_end;
struct frame_id step_frame_id;
+ struct frame_id step_stack_frame_id;
enum step_over_calls_kind step_over_calls;
CORE_ADDR step_resume_break_address;
int stop_after_trap;
int stop_soon;
- struct regcache *stop_registers;
-
- /* These are here because if call_function_by_hand has written some
- registers and then decides to call error(), we better not have changed
- any registers. */
- struct regcache *registers;
- /* A frame unique identifier. */
+ /* ID if the selected frame when the inferior function call was made. */
struct frame_id selected_frame_id;
- int breakpoint_proceeded;
- int restore_stack_info;
int proceed_to_finish;
+ int in_infcall;
};
-void
-write_inferior_status_register (struct inferior_status *inf_status, int regno,
- LONGEST val)
-{
- int size = register_size (current_gdbarch, regno);
- void *buf = alloca (size);
- store_signed_integer (buf, size, val);
- regcache_raw_write (inf_status->registers, regno, buf);
-}
-
/* Save all of the information associated with the inferior<==>gdb
- connection. INF_STATUS is a pointer to a "struct inferior_status"
- (defined in inferior.h). */
+ connection. */
struct inferior_status *
-save_inferior_status (int restore_stack_info)
+save_inferior_status (void)
{
struct inferior_status *inf_status = XMALLOC (struct inferior_status);
+ struct thread_info *tp = inferior_thread ();
+ struct inferior *inf = current_inferior ();
- inf_status->stop_signal = stop_signal;
- inf_status->stop_pc = stop_pc;
- inf_status->stop_step = stop_step;
+ inf_status->stop_step = tp->stop_step;
inf_status->stop_stack_dummy = stop_stack_dummy;
inf_status->stopped_by_random_signal = stopped_by_random_signal;
- inf_status->trap_expected = trap_expected;
- inf_status->step_range_start = step_range_start;
- inf_status->step_range_end = step_range_end;
- inf_status->step_frame_id = step_frame_id;
- inf_status->step_over_calls = step_over_calls;
+ inf_status->stepping_over_breakpoint = tp->trap_expected;
+ inf_status->step_range_start = tp->step_range_start;
+ inf_status->step_range_end = tp->step_range_end;
+ inf_status->step_frame_id = tp->step_frame_id;
+ inf_status->step_stack_frame_id = tp->step_stack_frame_id;
+ inf_status->step_over_calls = tp->step_over_calls;
inf_status->stop_after_trap = stop_after_trap;
- inf_status->stop_soon = stop_soon;
+ inf_status->stop_soon = inf->stop_soon;
/* Save original bpstat chain here; replace it with copy of chain.
If caller's caller is walking the chain, they'll be happier if we
hand them back the original chain when restore_inferior_status is
called. */
- inf_status->stop_bpstat = stop_bpstat;
- stop_bpstat = bpstat_copy (stop_bpstat);
- inf_status->breakpoint_proceeded = breakpoint_proceeded;
- inf_status->restore_stack_info = restore_stack_info;
- inf_status->proceed_to_finish = proceed_to_finish;
-
- inf_status->stop_registers = regcache_dup_no_passthrough (stop_registers);
+ inf_status->stop_bpstat = tp->stop_bpstat;
+ tp->stop_bpstat = bpstat_copy (tp->stop_bpstat);
+ inf_status->proceed_to_finish = tp->proceed_to_finish;
+ inf_status->in_infcall = tp->in_infcall;
- inf_status->registers = regcache_dup (current_regcache);
+ inf_status->selected_frame_id = get_frame_id (get_selected_frame (NULL));
- inf_status->selected_frame_id = get_frame_id (deprecated_selected_frame);
return inf_status;
}
return (1);
}
+/* Restore inferior session state to INF_STATUS. */
+
void
restore_inferior_status (struct inferior_status *inf_status)
{
- stop_signal = inf_status->stop_signal;
- stop_pc = inf_status->stop_pc;
- stop_step = inf_status->stop_step;
+ struct thread_info *tp = inferior_thread ();
+ struct inferior *inf = current_inferior ();
+
+ tp->stop_step = inf_status->stop_step;
stop_stack_dummy = inf_status->stop_stack_dummy;
stopped_by_random_signal = inf_status->stopped_by_random_signal;
- trap_expected = inf_status->trap_expected;
- step_range_start = inf_status->step_range_start;
- step_range_end = inf_status->step_range_end;
- step_frame_id = inf_status->step_frame_id;
- step_over_calls = inf_status->step_over_calls;
+ tp->trap_expected = inf_status->stepping_over_breakpoint;
+ tp->step_range_start = inf_status->step_range_start;
+ tp->step_range_end = inf_status->step_range_end;
+ tp->step_frame_id = inf_status->step_frame_id;
+ tp->step_stack_frame_id = inf_status->step_stack_frame_id;
+ tp->step_over_calls = inf_status->step_over_calls;
stop_after_trap = inf_status->stop_after_trap;
- stop_soon = inf_status->stop_soon;
- bpstat_clear (&stop_bpstat);
- stop_bpstat = inf_status->stop_bpstat;
- breakpoint_proceeded = inf_status->breakpoint_proceeded;
- proceed_to_finish = inf_status->proceed_to_finish;
-
- /* FIXME: Is the restore of stop_registers always needed. */
- regcache_xfree (stop_registers);
- stop_registers = inf_status->stop_registers;
-
- /* The inferior can be gone if the user types "print exit(0)"
- (and perhaps other times). */
- if (target_has_execution)
- /* NB: The register write goes through to the target. */
- regcache_cpy (current_regcache, inf_status->registers);
- regcache_xfree (inf_status->registers);
-
- /* FIXME: If we are being called after stopping in a function which
- is called from gdb, we should not be trying to restore the
- selected frame; it just prints a spurious error message (The
- message is useful, however, in detecting bugs in gdb (like if gdb
- clobbers the stack)). In fact, should we be restoring the
- inferior status at all in that case? . */
-
- if (target_has_stack && inf_status->restore_stack_info)
+ inf->stop_soon = inf_status->stop_soon;
+ bpstat_clear (&tp->stop_bpstat);
+ tp->stop_bpstat = inf_status->stop_bpstat;
+ inf_status->stop_bpstat = NULL;
+ tp->proceed_to_finish = inf_status->proceed_to_finish;
+ tp->in_infcall = inf_status->in_infcall;
+
+ if (target_has_stack)
{
/* The point of catch_errors is that if the stack is clobbered,
walking the stack might encounter a garbage pointer and
/* Error in restoring the selected frame. Select the innermost
frame. */
select_frame (get_current_frame ());
-
}
xfree (inf_status);
{
/* See save_inferior_status for info on stop_bpstat. */
bpstat_clear (&inf_status->stop_bpstat);
- regcache_xfree (inf_status->registers);
- regcache_xfree (inf_status->stop_registers);
xfree (inf_status);
}
-
+\f
int
-inferior_has_forked (int pid, int *child_pid)
+inferior_has_forked (ptid_t pid, ptid_t *child_pid)
{
struct target_waitstatus last;
ptid_t last_ptid;
if (last.kind != TARGET_WAITKIND_FORKED)
return 0;
- if (ptid_get_pid (last_ptid) != pid)
+ if (!ptid_equal (last_ptid, pid))
return 0;
*child_pid = last.value.related_pid;
}
int
-inferior_has_vforked (int pid, int *child_pid)
+inferior_has_vforked (ptid_t pid, ptid_t *child_pid)
{
struct target_waitstatus last;
ptid_t last_ptid;
if (last.kind != TARGET_WAITKIND_VFORKED)
return 0;
- if (ptid_get_pid (last_ptid) != pid)
+ if (!ptid_equal (last_ptid, pid))
return 0;
*child_pid = last.value.related_pid;
}
int
-inferior_has_execd (int pid, char **execd_pathname)
+inferior_has_execd (ptid_t pid, char **execd_pathname)
{
struct target_waitstatus last;
ptid_t last_ptid;
if (last.kind != TARGET_WAITKIND_EXECD)
return 0;
- if (ptid_get_pid (last_ptid) != pid)
+ if (!ptid_equal (last_ptid, pid))
return 0;
*execd_pathname = xstrdup (last.value.execd_pathname);
&& ptid1.tid == ptid2.tid);
}
+/* Returns true if PTID represents a process. */
+
+int
+ptid_is_pid (ptid_t ptid)
+{
+ if (ptid_equal (minus_one_ptid, ptid))
+ return 0;
+ if (ptid_equal (null_ptid, ptid))
+ return 0;
+
+ return (ptid_get_lwp (ptid) == 0 && ptid_get_tid (ptid) == 0);
+}
+
/* restore_inferior_ptid() will be used by the cleanup machinery
to restore the inferior_ptid value saved in a call to
save_inferior_ptid(). */
}
\f
+/* User interface for reverse debugging:
+ Set exec-direction / show exec-direction commands
+ (returns error unless target implements to_set_exec_direction method). */
+
+enum exec_direction_kind execution_direction = EXEC_FORWARD;
+static const char exec_forward[] = "forward";
+static const char exec_reverse[] = "reverse";
+static const char *exec_direction = exec_forward;
+static const char *exec_direction_names[] = {
+ exec_forward,
+ exec_reverse,
+ NULL
+};
+
+static void
+set_exec_direction_func (char *args, int from_tty,
+ struct cmd_list_element *cmd)
+{
+ if (target_can_execute_reverse)
+ {
+ if (!strcmp (exec_direction, exec_forward))
+ execution_direction = EXEC_FORWARD;
+ else if (!strcmp (exec_direction, exec_reverse))
+ execution_direction = EXEC_REVERSE;
+ }
+}
+
+static void
+show_exec_direction_func (struct ui_file *out, int from_tty,
+ struct cmd_list_element *cmd, const char *value)
+{
+ switch (execution_direction) {
+ case EXEC_FORWARD:
+ fprintf_filtered (out, _("Forward.\n"));
+ break;
+ case EXEC_REVERSE:
+ fprintf_filtered (out, _("Reverse.\n"));
+ break;
+ case EXEC_ERROR:
+ default:
+ fprintf_filtered (out,
+ _("Forward (target `%s' does not support exec-direction).\n"),
+ target_shortname);
+ break;
+ }
+}
+
+/* User interface for non-stop mode. */
+
+int non_stop = 0;
+static int non_stop_1 = 0;
+
+static void
+set_non_stop (char *args, int from_tty,
+ struct cmd_list_element *c)
+{
+ if (target_has_execution)
+ {
+ non_stop_1 = non_stop;
+ error (_("Cannot change this setting while the inferior is running."));
+ }
+
+ non_stop = non_stop_1;
+}
+
+static void
+show_non_stop (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c, const char *value)
+{
+ fprintf_filtered (file,
+ _("Controlling the inferior in non-stop mode is %s.\n"),
+ value);
+}
+
static void
-build_infrun (void)
+show_schedule_multiple (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c, const char *value)
{
- stop_registers = regcache_xmalloc (current_gdbarch);
+ fprintf_filtered (file, _("\
+Resuming the execution of threads of all processes is %s.\n"), value);
}
void
int numsigs;
struct cmd_list_element *c;
- DEPRECATED_REGISTER_GDBARCH_SWAP (stop_registers);
- deprecated_register_gdbarch_swap (NULL, 0, build_infrun);
-
add_info ("signals", signals_info, _("\
What debugger does when program gets various signals.\n\
Specify a signal as argument to print info on that signal only."));
show_debug_infrun,
&setdebuglist, &showdebuglist);
+ add_setshow_boolean_cmd ("displaced", class_maintenance, &debug_displaced, _("\
+Set displaced stepping debugging."), _("\
+Show displaced stepping debugging."), _("\
+When non-zero, displaced stepping specific debugging is enabled."),
+ NULL,
+ show_debug_displaced,
+ &setdebuglist, &showdebuglist);
+
+ add_setshow_boolean_cmd ("non-stop", no_class,
+ &non_stop_1, _("\
+Set whether gdb controls the inferior in non-stop mode."), _("\
+Show whether gdb controls the inferior in non-stop mode."), _("\
+When debugging a multi-threaded program and this setting is\n\
+off (the default, also called all-stop mode), when one thread stops\n\
+(for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
+all other threads in the program while you interact with the thread of\n\
+interest. When you continue or step a thread, you can allow the other\n\
+threads to run, or have them remain stopped, but while you inspect any\n\
+thread's state, all threads stop.\n\
+\n\
+In non-stop mode, when one thread stops, other threads can continue\n\
+to run freely. You'll be able to step each thread independently,\n\
+leave it stopped or free to run as needed."),
+ set_non_stop,
+ show_non_stop,
+ &setlist,
+ &showlist);
+
numsigs = (int) TARGET_SIGNAL_LAST;
signal_stop = (unsigned char *) xmalloc (sizeof (signal_stop[0]) * numsigs);
signal_print = (unsigned char *)
show_scheduler_mode,
&setlist, &showlist);
+ add_setshow_boolean_cmd ("schedule-multiple", class_run, &sched_multi, _("\
+Set mode for resuming threads of all processes."), _("\
+Show mode for resuming threads of all processes."), _("\
+When on, execution commands (such as 'continue' or 'next') resume all\n\
+threads of all processes. When off (which is the default), execution\n\
+commands only resume the threads of the current process. The set of\n\
+threads that are resumed is further refined by the scheduler-locking\n\
+mode (see help set scheduler-locking)."),
+ NULL,
+ show_schedule_multiple,
+ &setlist, &showlist);
+
add_setshow_boolean_cmd ("step-mode", class_run, &step_stop_if_no_debug, _("\
Set mode of the step operation."), _("\
Show mode of the step operation."), _("\
show_step_stop_if_no_debug,
&setlist, &showlist);
+ add_setshow_enum_cmd ("displaced-stepping", class_run,
+ can_use_displaced_stepping_enum,
+ &can_use_displaced_stepping, _("\
+Set debugger's willingness to use displaced stepping."), _("\
+Show debugger's willingness to use displaced stepping."), _("\
+If on, gdb will use displaced stepping to step over breakpoints if it is\n\
+supported by the target architecture. If off, gdb will not use displaced\n\
+stepping to step over breakpoints, even if such is supported by the target\n\
+architecture. If auto (which is the default), gdb will use displaced stepping\n\
+if the target architecture supports it and non-stop mode is active, but will not\n\
+use it in all-stop mode (see help set non-stop)."),
+ NULL,
+ show_can_use_displaced_stepping,
+ &setlist, &showlist);
+
+ add_setshow_enum_cmd ("exec-direction", class_run, exec_direction_names,
+ &exec_direction, _("Set direction of execution.\n\
+Options are 'forward' or 'reverse'."),
+ _("Show direction of execution (forward/reverse)."),
+ _("Tells gdb whether to execute forward or backward."),
+ set_exec_direction_func, show_exec_direction_func,
+ &setlist, &showlist);
+
/* ptid initializations */
null_ptid = ptid_build (0, 0, 0);
minus_one_ptid = ptid_build (-1, 0, 0);
inferior_ptid = null_ptid;
target_last_wait_ptid = minus_one_ptid;
+ displaced_step_ptid = null_ptid;
+
+ observer_attach_thread_ptid_changed (infrun_thread_ptid_changed);
+ observer_attach_thread_stop_requested (infrun_thread_stop_requested);
+ observer_attach_thread_exit (infrun_thread_thread_exit);
+
+ /* Explicitly create without lookup, since that tries to create a
+ value with a void typed value, and when we get here, gdbarch
+ isn't initialized yet. At this point, we're quite sure there
+ isn't another convenience variable of the same name. */
+ create_internalvar_type_lazy ("_siginfo", siginfo_make_value);
}
projects / deliverable / binutils-gdb.git / blobdiff