/* The process this displaced step state refers to. */
int pid;
+ /* True if preparing a displaced step ever failed. If so, we won't
+ try displaced stepping for this inferior again. */
+ int failed_before;
+
/* If this is not null_ptid, this is the thread carrying out a
displaced single-step in process PID. This thread's state will
require fixing up once it has completed its step. */
fprintf_filtered (file,
_("Debugger's willingness to use displaced stepping "
"to step over breakpoints is %s (currently %s).\n"),
- value, non_stop ? "on" : "off");
+ value, target_is_non_stop_p () ? "on" : "off");
else
fprintf_filtered (file,
_("Debugger's willingness to use displaced stepping "
}
/* Return non-zero if displaced stepping can/should be used to step
- over breakpoints. */
+ over breakpoints of thread TP. */
static int
-use_displaced_stepping (struct gdbarch *gdbarch)
+use_displaced_stepping (struct thread_info *tp)
{
- return (((can_use_displaced_stepping == AUTO_BOOLEAN_AUTO && non_stop)
+ struct regcache *regcache = get_thread_regcache (tp->ptid);
+ struct gdbarch *gdbarch = get_regcache_arch (regcache);
+ struct displaced_step_inferior_state *displaced_state;
+
+ displaced_state = get_displaced_stepping_state (ptid_get_pid (tp->ptid));
+
+ return (((can_use_displaced_stepping == AUTO_BOOLEAN_AUTO
+ && target_is_non_stop_p ())
|| can_use_displaced_stepping == AUTO_BOOLEAN_TRUE)
&& gdbarch_displaced_step_copy_insn_p (gdbarch)
- && find_record_target () == NULL);
+ && find_record_target () == NULL
+ && (displaced_state == NULL
+ || !displaced_state->failed_before));
}
/* Clean out any stray displaced stepping state. */
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. */
+ stepped now; 0 if displaced stepping this thread got queued; or -1
+ if this instruction can't be displaced stepped. */
+
static int
-displaced_step_prepare (ptid_t ptid)
+displaced_step_prepare_throw (ptid_t ptid)
{
struct cleanup *old_cleanups, *ignore_cleanups;
struct thread_info *tp = find_thread_ptid (ptid);
closure = gdbarch_displaced_step_copy_insn (gdbarch,
original, copy, regcache);
-
- /* We don't support the fully-simulated case at present. */
- gdb_assert (closure);
+ if (closure == NULL)
+ {
+ /* The architecture doesn't know how or want to displaced step
+ this instruction or instruction sequence. Fallback to
+ stepping over the breakpoint in-line. */
+ do_cleanups (old_cleanups);
+ return -1;
+ }
/* Save the information we need to fix things up if the step
succeeds. */
return 1;
}
+/* Wrapper for displaced_step_prepare_throw that disabled further
+ attempts at displaced stepping if we get a memory error. */
+
+static int
+displaced_step_prepare (ptid_t ptid)
+{
+ int prepared = -1;
+
+ TRY
+ {
+ prepared = displaced_step_prepare_throw (ptid);
+ }
+ CATCH (ex, RETURN_MASK_ERROR)
+ {
+ struct displaced_step_inferior_state *displaced_state;
+
+ if (ex.error != MEMORY_ERROR)
+ throw_exception (ex);
+
+ if (debug_infrun)
+ {
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: disabling displaced stepping: %s\n",
+ ex.message);
+ }
+
+ /* Be verbose if "set displaced-stepping" is "on", silent if
+ "auto". */
+ if (can_use_displaced_stepping == AUTO_BOOLEAN_TRUE)
+ {
+ warning (_("disabling displaced stepping: %s\n"),
+ ex.message);
+ }
+
+ /* Disable further displaced stepping attempts. */
+ displaced_state
+ = get_displaced_stepping_state (ptid_get_pid (ptid));
+ displaced_state->failed_before = 1;
+ }
+ END_CATCH
+
+ return prepared;
+}
+
static void
write_memory_ptid (ptid_t ptid, CORE_ADDR memaddr,
const gdb_byte *myaddr, int len)
static void prepare_to_wait (struct execution_control_state *ecs);
static int keep_going_stepped_thread (struct thread_info *tp);
static int thread_still_needs_step_over (struct thread_info *tp);
+static void stop_all_threads (void);
/* Are there any pending step-over requests? If so, run all we can
now and return true. Otherwise, return false. */
struct execution_control_state *ecs = &ecss;
enum step_over_what step_what;
int must_be_in_line;
- struct regcache *regcache = get_thread_regcache (tp->ptid);
- struct gdbarch *gdbarch = get_regcache_arch (regcache);
next = thread_step_over_chain_next (tp);
step_what = thread_still_needs_step_over (tp);
must_be_in_line = ((step_what & STEP_OVER_WATCHPOINT)
|| ((step_what & STEP_OVER_BREAKPOINT)
- && !use_displaced_stepping (gdbarch)));
+ && !use_displaced_stepping (tp)));
/* We currently stop all threads of all processes to step-over
in-line. If we need to start a new in-line step-over, let
because we wouldn't be able to resume anything else until the
target stops again. In non-stop, the resume always resumes
only TP, so it's OK to let the thread resume freely. */
- if (!non_stop && !step_what)
+ if (!target_is_non_stop_p () && !step_what)
continue;
switch_to_thread (tp->ptid);
return 1;
}
- if (!non_stop)
+ if (!target_is_non_stop_p ())
{
/* On all-stop, shouldn't have resumed unless we needed a
step over. */
return resume_ptid;
}
+/* Return a ptid representing the set of threads that we will resume,
+ in the perspective of the target, assuming run control handling
+ does not require leaving some threads stopped (e.g., stepping past
+ breakpoint). USER_STEP indicates whether we're about to start the
+ target for a stepping command. */
+
+static ptid_t
+internal_resume_ptid (int user_step)
+{
+ /* In non-stop, we always control threads individually. Note that
+ the target may always work in non-stop mode even with "set
+ non-stop off", in which case user_visible_resume_ptid could
+ return a wildcard ptid. */
+ if (target_is_non_stop_p ())
+ return inferior_ptid;
+ else
+ return user_visible_resume_ptid (user_step);
+}
+
/* Wrapper for target_resume, that handles infrun-specific
bookkeeping. */
insert_single_step_breakpoint (gdbarch, aspace, pc);
insert_breakpoints ();
- resume_ptid = user_visible_resume_ptid (user_step);
+ resume_ptid = internal_resume_ptid (user_step);
do_target_resume (resume_ptid, 0, GDB_SIGNAL_0);
discard_cleanups (old_cleanups);
tp->resumed = 1;
We can't use displaced stepping when we are waiting for vfork_done
event, displaced stepping breaks the vfork child similarly as single
step software breakpoint. */
- if (use_displaced_stepping (gdbarch)
- && tp->control.trap_expected
+ if (tp->control.trap_expected
+ && use_displaced_stepping (tp)
&& !step_over_info_valid_p ()
&& sig == GDB_SIGNAL_0
&& !current_inferior ()->waiting_for_vfork_done)
{
- struct displaced_step_inferior_state *displaced;
+ int prepared = displaced_step_prepare (inferior_ptid);
- if (!displaced_step_prepare (inferior_ptid))
+ if (prepared == 0)
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog,
discard_cleanups (old_cleanups);
return;
}
+ else if (prepared < 0)
+ {
+ /* Fallback to stepping over the breakpoint in-line. */
- /* Update pc to reflect the new address from which we will execute
- instructions due to displaced stepping. */
- pc = regcache_read_pc (get_thread_regcache (inferior_ptid));
+ if (target_is_non_stop_p ())
+ stop_all_threads ();
- displaced = get_displaced_stepping_state (ptid_get_pid (inferior_ptid));
- step = gdbarch_displaced_step_hw_singlestep (gdbarch,
- displaced->step_closure);
+ set_step_over_info (get_regcache_aspace (regcache),
+ regcache_read_pc (regcache), 0);
+
+ step = maybe_software_singlestep (gdbarch, pc);
+
+ insert_breakpoints ();
+ }
+ else if (prepared > 0)
+ {
+ struct displaced_step_inferior_state *displaced;
+
+ /* Update pc to reflect the new address from which we will
+ execute instructions due to displaced stepping. */
+ pc = regcache_read_pc (get_thread_regcache (inferior_ptid));
+
+ displaced = get_displaced_stepping_state (ptid_get_pid (inferior_ptid));
+ step = gdbarch_displaced_step_hw_singlestep (gdbarch,
+ displaced->step_closure);
+ }
}
/* Do we need to do it the hard way, w/temp breakpoints? */
use singlestep breakpoint. */
gdb_assert (!(thread_has_single_step_breakpoints_set (tp) && step));
- /* 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. */
- resume_ptid = user_visible_resume_ptid (user_step);
-
- /* Maybe resume a single thread after all. */
+ /* Decide the set of threads to ask the target to resume. */
if ((step || thread_has_single_step_breakpoints_set (tp))
&& tp->control.trap_expected)
{
breakpoint if allowed to run. */
resume_ptid = inferior_ptid;
}
+ else
+ resume_ptid = internal_resume_ptid (user_step);
if (execution_direction != EXEC_REVERSE
&& step && breakpoint_inserted_here_p (aspace, pc))
}
if (debug_displaced
- && use_displaced_stepping (gdbarch)
&& tp->control.trap_expected
+ && use_displaced_stepping (tp)
&& !step_over_info_valid_p ())
{
struct regcache *resume_regcache = get_thread_regcache (tp->ptid);
other thread was already doing one. In either case, don't
resume anything else until the step-over is finished. */
}
- else if (started && !non_stop)
+ else if (started && !target_is_non_stop_p ())
{
/* A new displaced stepping sequence was started. In all-stop,
we can't talk to the target anymore until it next stops. */
}
+ else if (!non_stop && target_is_non_stop_p ())
+ {
+ /* In all-stop, but the target is always in non-stop mode.
+ Start all other threads that are implicitly resumed too. */
+ ALL_NON_EXITED_THREADS (tp)
+ {
+ /* Ignore threads of processes we're not resuming. */
+ if (!ptid_match (tp->ptid, resume_ptid))
+ continue;
+
+ if (tp->resumed)
+ {
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: proceed: [%s] resumed\n",
+ target_pid_to_str (tp->ptid));
+ gdb_assert (tp->executing || tp->suspend.waitstatus_pending_p);
+ continue;
+ }
+
+ if (thread_is_in_step_over_chain (tp))
+ {
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: proceed: [%s] needs step-over\n",
+ target_pid_to_str (tp->ptid));
+ continue;
+ }
+
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: proceed: resuming %s\n",
+ target_pid_to_str (tp->ptid));
+
+ reset_ecs (ecs, tp);
+ switch_to_thread (tp->ptid);
+ keep_going_pass_signal (ecs);
+ if (!ecs->wait_some_more)
+ error ("Command aborted.");
+ }
+ }
else if (!tp->resumed && !thread_is_in_step_over_chain (tp))
{
/* The thread wasn't started, and isn't queued, run it now. */
if (!target_has_execution || ptid_equal (inferior_ptid, null_ptid))
return;
- if (non_stop)
+ if (target_is_non_stop_p ())
{
/* If in non-stop mode, only the current thread stopped. */
func (inferior_thread ());
/* 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)
+ if (!target_is_non_stop_p ())
ts_old_chain = make_cleanup (finish_thread_state_cleanup, &minus_one_ptid);
else
ts_old_chain = make_cleanup (finish_thread_state_cleanup, &ecs->ptid);
to get the "stopped by SW BP and needs adjustment" info out of
the target/kernel (and thus never reach here; see above). */
if (software_breakpoint_inserted_here_p (aspace, breakpoint_pc)
- || (non_stop && moribund_breakpoint_here_p (aspace, breakpoint_pc)))
+ || (target_is_non_stop_p ()
+ && moribund_breakpoint_here_p (aspace, breakpoint_pc)))
{
struct cleanup *old_cleanups = make_cleanup (null_cleanup, NULL);
ptid_t entry_ptid;
struct cleanup *old_chain;
- gdb_assert (non_stop);
+ gdb_assert (target_is_non_stop_p ());
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: stop_all_threads\n");
{
ptid_t mark_ptid;
- if (!non_stop)
+ if (!target_is_non_stop_p ())
mark_ptid = minus_one_ptid;
else if (ecs->ws.kind == TARGET_WAITKIND_SIGNALLED
|| ecs->ws.kind == TARGET_WAITKIND_EXITED)
child = ecs->ws.value.related_pid;
/* In non-stop mode, also resume the other branch. */
- if (non_stop && !detach_fork)
+ if (!detach_fork && (non_stop
+ || (sched_multi && target_is_non_stop_p ())))
{
if (follow_child)
switch_to_thread (parent);
clear_step_over_info ();
}
- if (!non_stop)
+ if (!target_is_non_stop_p ())
return 0;
/* Start a new step-over in another thread if there's one that
/* Reset trap_expected to ensure breakpoints are re-inserted. */
ecs->event_thread->control.trap_expected = 0;
- if (non_stop)
+ if (target_is_non_stop_p ())
{
+ /* Either "set non-stop" is "on", or the target is
+ always in non-stop mode. In this case, we have a bit
+ more work to do. Resume the current thread, and if
+ we had paused all threads, restart them while the
+ signal handler runs. */
keep_going (ecs);
- /* The step-over has been canceled temporarily while the
- signal handler executes. */
if (was_in_line)
{
- /* We had paused all threads, restart them. */
restart_threads (ecs->event_thread);
}
else if (debug_infrun)
static int
switch_back_to_stepped_thread (struct execution_control_state *ecs)
{
- if (!non_stop)
+ if (!target_is_non_stop_p ())
{
struct thread_info *tp;
struct thread_info *stepping_thread;
ALL_NON_EXITED_THREADS (tp)
{
- /* Ignore threads of processes we're not resuming. */
+ /* Ignore threads of processes the caller is not
+ resuming. */
if (!sched_multi
&& ptid_get_pid (tp->ptid) != ptid_get_pid (ecs->ptid))
continue;
stop_pc);
tp->resumed = 1;
- resume_ptid = user_visible_resume_ptid (tp->control.stepping_command);
+ resume_ptid = internal_resume_ptid (tp->control.stepping_command);
do_target_resume (resume_ptid, 0, GDB_SIGNAL_0);
}
else
/* Let callers know we don't want to wait for the inferior anymore. */
ecs->wait_some_more = 0;
+
+ /* If all-stop, but the target is always in non-stop mode, stop all
+ threads now that we're presenting the stop to the user. */
+ if (!non_stop && target_is_non_stop_p ())
+ stop_all_threads ();
}
/* Like keep_going, but passes the signal to the inferior, even if the
watchpoint. The instruction copied to the scratch pad would
still trigger the watchpoint. */
if (remove_bp
- && (remove_wps
- || !use_displaced_stepping (get_regcache_arch (regcache))))
+ && (remove_wps || !use_displaced_stepping (ecs->event_thread)))
{
set_step_over_info (get_regcache_aspace (regcache),
regcache_read_pc (regcache), remove_wps);
insert_breakpoints below, because that removes the breakpoint
we're about to step over, otherwise other threads could miss
it. */
- if (step_over_info_valid_p () && non_stop)
+ if (step_over_info_valid_p () && target_is_non_stop_p ())
stop_all_threads ();
/* Stop stepping if inserting breakpoints fails. */
projects / deliverable / binutils-gdb.git / blobdiff