#include "gdb_wait.h"
#include "gdbcore.h"
#include "gdbcmd.h"
+#include "cli/cli-script.h"
#include "target.h"
#include "gdbthread.h"
#include "annotate.h"
static int may_follow_exec = MAY_FOLLOW_EXEC;
-/* resume and wait_for_inferior use this to ensure that when
- stepping over a hit breakpoint in a threaded application
- only the thread that hit the breakpoint is stepped and the
- other threads don't continue. This prevents having another
- thread run past the breakpoint while it is temporarily
- removed.
-
- This is not thread-specific, so it isn't saved as part of
- the infrun state.
-
- Versions of gdb which don't use the "step == this thread steps
- and others continue" model but instead use the "step == this
- thread steps and others wait" shouldn't do this. */
-
-static int thread_step_needed = 0;
-
-/* This is true if thread_step_needed should actually be used. At
- present this is only true for HP-UX native. */
-
-#ifndef USE_THREAD_STEP_NEEDED
-#define USE_THREAD_STEP_NEEDED (0)
-#endif
-
-static int use_thread_step_needed = USE_THREAD_STEP_NEEDED;
-
/* GET_LONGJMP_TARGET returns the PC at which longjmp() will resume the
program. It needs to examine the jmp_buf argument and extract the PC
from it. The return value is non-zero on success, zero otherwise. */
#endif
-/* Some machines have trampoline code that sits between function callers
- and the actual functions themselves. If this machine doesn't have
- such things, disable their processing. */
-
-#ifndef SKIP_TRAMPOLINE_CODE
-#define SKIP_TRAMPOLINE_CODE(pc) 0
-#endif
-
/* Dynamic function trampolines are similar to solib trampolines in that they
are between the caller and the callee. The difference is that when you
enter a dynamic trampoline, you can't determine the callee's address. Some
}
-
-
/* Resume the inferior, but allow a QUIT. This is useful if the user
wants to interrupt some lengthy single-stepping operation
(for child processes, the SIGINT goes to the inferior, and so
struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
QUIT;
-#ifdef CANNOT_STEP_BREAKPOINT
- /* 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 ()))
- step = 0;
-#endif
+ /* FIXME: calling breakpoint_here_p (read_pc ()) three times! */
+
/* Some targets (e.g. Solaris x86) have a kernel bug when stepping
over an instruction that causes a page fault without triggering
{
ptid_t resume_ptid;
- if (use_thread_step_needed && thread_step_needed)
+ resume_ptid = RESUME_ALL; /* Default */
+
+ if ((step || singlestep_breakpoints_inserted_p) &&
+ !breakpoints_inserted && breakpoint_here_p (read_pc ()))
{
- /* We stopped on a BPT instruction;
- don't continue other threads and
- just step this thread. */
- thread_step_needed = 0;
+ /* 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. */
- if (!breakpoint_here_p (read_pc ()))
- {
- /* Breakpoint deleted: ok to do regular resume
- where all the threads either step or continue. */
- resume_ptid = RESUME_ALL;
- }
- else
- {
- if (!step)
- {
- warning ("Internal error, changing continue to step.");
- remove_breakpoints ();
- breakpoints_inserted = 0;
- trap_expected = 1;
- step = 1;
- }
- resume_ptid = inferior_ptid;
- }
+ resume_ptid = inferior_ptid;
}
- else
+
+ if ((scheduler_mode == schedlock_on) ||
+ (scheduler_mode == schedlock_step &&
+ (step || singlestep_breakpoints_inserted_p)))
{
- /* Vanilla resume. */
- if ((scheduler_mode == schedlock_on) ||
- (scheduler_mode == schedlock_step && step != 0))
+ /* User-settable 'scheduler' mode requires solo thread resume. */
resume_ptid = inferior_ptid;
- else
- resume_ptid = RESUME_ALL;
}
+
+#ifdef CANNOT_STEP_BREAKPOINT
+ /* 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 ()))
+ step = 0;
+#endif
target_resume (resume_ptid, step, sig);
}
else
{
write_pc (addr);
-
- /* New address; we don't need to single-step a thread
- over a breakpoint we just hit, 'cause we aren't
- continuing from there.
-
- It's not worth worrying about the case where a user
- asks for a "jump" at the current PC--if they get the
- hiccup of re-hiting a hit breakpoint, what else do
- they expect? */
- thread_step_needed = 0;
}
#ifdef PREPARE_TO_PROCEED
if (PREPARE_TO_PROCEED (1) && breakpoint_here_p (read_pc ()))
{
oneproc = 1;
- thread_step_needed = 1;
}
#endif /* PREPARE_TO_PROCEED */
/* Fill in with reasonable starting values. */
init_execution_control_state (ecs);
- thread_step_needed = 0;
-
/* We'll update this if & when we switch to a new thread. */
previous_inferior_ptid = inferior_ptid;
/* Fill in with reasonable starting values. */
init_execution_control_state (async_ecs);
- thread_step_needed = 0;
-
/* We'll update this if & when we switch to a new thread. */
previous_inferior_ptid = inferior_ptid;
*status = target_last_waitstatus;
}
+/* Switch thread contexts, maintaining "infrun state". */
+
+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,
+ prev_func_start, prev_func_name,
+ trap_expected, step_resume_breakpoint,
+ through_sigtramp_breakpoint, step_range_start,
+ step_range_end, step_frame_address,
+ ecs->handling_longjmp, ecs->another_trap,
+ ecs->stepping_through_solib_after_catch,
+ ecs->stepping_through_solib_catchpoints,
+ ecs->stepping_through_sigtramp,
+ ecs->current_line, ecs->current_symtab,
+ step_sp);
+
+ /* Load infrun state for the new thread. */
+ load_infrun_state (ecs->ptid, &prev_pc,
+ &prev_func_start, &prev_func_name,
+ &trap_expected, &step_resume_breakpoint,
+ &through_sigtramp_breakpoint, &step_range_start,
+ &step_range_end, &step_frame_address,
+ &ecs->handling_longjmp, &ecs->another_trap,
+ &ecs->stepping_through_solib_after_catch,
+ &ecs->stepping_through_solib_catchpoints,
+ &ecs->stepping_through_sigtramp,
+ &ecs->current_line, &ecs->current_symtab,
+ &step_sp);
+ }
+ inferior_ptid = ecs->ptid;
+}
+
+
/* 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. */
{
switch (ecs->infwait_state)
{
- case infwait_normal_state:
- /* Since we've done a wait, we have a new event. Don't
- carry over any expectations about needing to step over a
- breakpoint. */
- thread_step_needed = 0;
+ case infwait_thread_hop_state:
+ /* Cancel the waiton_ptid. */
+ ecs->waiton_ptid = pid_to_ptid (-1);
+ /* Fall thru to the normal_state case. */
+ case infwait_normal_state:
/* See comments where a TARGET_WAITKIND_SYSCALL_RETURN event
is serviced in this loop, below. */
if (ecs->enable_hw_watchpoints_after_wait)
stepped_after_stopped_by_watchpoint = 0;
break;
- case infwait_thread_hop_state:
- insert_breakpoints ();
-
- /* We need to restart all the threads now,
- * unless we're running in scheduler-locked mode.
- * Use currently_stepping to determine whether to
- * step or continue.
- */
-
- 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);
- ecs->infwait_state = infwait_normal_state;
- prepare_to_wait (ecs);
- return;
-
case infwait_nullified_state:
break;
stop_pc = read_pc_pid (ecs->ptid);
ecs->saved_inferior_ptid = inferior_ptid;
inferior_ptid = ecs->ptid;
- stop_bpstat = bpstat_stop_status (&stop_pc, currently_stepping (ecs));
+ /* The second argument of bpstat_stop_status is meant to help
+ distinguish between a breakpoint trap and a singlestep trap.
+ This is only important on targets where DECR_PC_AFTER_BREAK
+ is non-zero. The prev_pc test is meant to distinguish between
+ singlestepping a trap instruction, and singlestepping thru a
+ jump to the instruction following a trap instruction. */
+
+ stop_bpstat = bpstat_stop_status (&stop_pc,
+ currently_stepping (ecs) &&
+ prev_pc !=
+ stop_pc - DECR_PC_AFTER_BREAK);
ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
inferior_ptid = ecs->saved_inferior_ptid;
goto process_event_stop_test;
}
stop_pc = read_pc ();
- stop_bpstat = bpstat_stop_status (&stop_pc, currently_stepping (ecs));
+ /* The second argument of bpstat_stop_status is meant to help
+ distinguish between a breakpoint trap and a singlestep trap.
+ This is only important on targets where DECR_PC_AFTER_BREAK
+ is non-zero. The prev_pc test is meant to distinguish between
+ singlestepping a trap instruction, and singlestepping thru a
+ jump to the instruction following a trap instruction. */
+
+ stop_bpstat = bpstat_stop_status (&stop_pc,
+ currently_stepping (ecs) &&
+ prev_pc !=
+ stop_pc - DECR_PC_AFTER_BREAK);
ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
goto process_event_stop_test;
stop_pc = read_pc_pid (ecs->ptid);
ecs->saved_inferior_ptid = inferior_ptid;
inferior_ptid = ecs->ptid;
- stop_bpstat = bpstat_stop_status (&stop_pc, currently_stepping (ecs));
+ /* The second argument of bpstat_stop_status is meant to help
+ distinguish between a breakpoint trap and a singlestep trap.
+ This is only important on targets where DECR_PC_AFTER_BREAK
+ is non-zero. The prev_pc test is meant to distinguish between
+ singlestepping a trap instruction, and singlestepping thru a
+ jump to the instruction following a trap instruction. */
+
+ stop_bpstat = bpstat_stop_status (&stop_pc,
+ currently_stepping (ecs) &&
+ prev_pc !=
+ stop_pc - DECR_PC_AFTER_BREAK);
ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
inferior_ptid = ecs->saved_inferior_ptid;
goto process_event_stop_test;
/* Saw a breakpoint, but it was hit by the wrong thread.
Just continue. */
- write_pc_pid (stop_pc - DECR_PC_AFTER_BREAK, ecs->ptid);
+ if (DECR_PC_AFTER_BREAK)
+ write_pc_pid (stop_pc - DECR_PC_AFTER_BREAK, ecs->ptid);
remove_status = remove_breakpoints ();
/* Did we fail to remove breakpoints? If so, try
then either :-) or execs. */
if (remove_status != 0)
{
- write_pc_pid (stop_pc - DECR_PC_AFTER_BREAK + 4, ecs->ptid);
+ /* FIXME! This is obviously non-portable! */
+ write_pc_pid (stop_pc - DECR_PC_AFTER_BREAK + 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),
}
else
{ /* Single step */
- target_resume (ecs->ptid, 1, TARGET_SIGNAL_0);
- /* FIXME: What if a signal arrives instead of the
- single-step happening? */
-
+ 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;
- prepare_to_wait (ecs);
+ keep_going (ecs);
+ registers_changed ();
return;
}
}
- else
- {
- /* This breakpoint matches--either it is the right
- thread or it's a generic breakpoint for all threads.
- Remember that we'll need to step just _this_ thread
- on any following user continuation! */
- thread_step_needed = 1;
- }
}
}
else
/* It's a SIGTRAP or a signal we're interested in. Switch threads,
and fall into the rest of wait_for_inferior(). */
- /* 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,
- prev_func_start, prev_func_name,
- trap_expected, step_resume_breakpoint,
- through_sigtramp_breakpoint,
- step_range_start, step_range_end,
- step_frame_address, ecs->handling_longjmp,
- ecs->another_trap,
- ecs->stepping_through_solib_after_catch,
- ecs->stepping_through_solib_catchpoints,
- ecs->stepping_through_sigtramp);
-
- /* Load infrun state for the new thread. */
- load_infrun_state (ecs->ptid, &prev_pc,
- &prev_func_start, &prev_func_name,
- &trap_expected, &step_resume_breakpoint,
- &through_sigtramp_breakpoint,
- &step_range_start, &step_range_end,
- &step_frame_address, &ecs->handling_longjmp,
- &ecs->another_trap,
- &ecs->stepping_through_solib_after_catch,
- &ecs->stepping_through_solib_catchpoints,
- &ecs->stepping_through_sigtramp);
- }
-
- inferior_ptid = ecs->ptid;
+ context_switch (ecs);
if (context_hook)
context_hook (pid_to_thread_id (ecs->ptid));
includes evaluating watchpoints, things will come to a
stop in the correct manner. */
- write_pc (stop_pc - DECR_PC_AFTER_BREAK);
+ if (DECR_PC_AFTER_BREAK)
+ write_pc (stop_pc - DECR_PC_AFTER_BREAK);
remove_breakpoints ();
registers_changed ();
else
{
/* See if there is a breakpoint at the current PC. */
+
+ /* The second argument of bpstat_stop_status is meant to help
+ distinguish between a breakpoint trap and a singlestep trap.
+ This is only important on targets where DECR_PC_AFTER_BREAK
+ is non-zero. The prev_pc test is meant to distinguish between
+ singlestepping a trap instruction, and singlestepping thru a
+ jump to the instruction following a trap instruction. */
+
stop_bpstat = bpstat_stop_status
(&stop_pc,
/* Pass TRUE if our reason for stopping is something other
sigtramp, which is detected by a new stack pointer value
below any usual function calling stack adjustments. */
(currently_stepping (ecs)
+ && prev_pc != stop_pc - DECR_PC_AFTER_BREAK
&& !(step_range_end
&& INNER_THAN (read_sp (), (step_sp - 16))))
);
case BPSTAT_WHAT_SINGLE:
if (breakpoints_inserted)
{
- thread_step_needed = 1;
remove_breakpoints ();
}
breakpoints_inserted = 0;
{
/* It's a subroutine call. */
- if (step_over_calls == STEP_OVER_NONE)
+ if ((step_over_calls == STEP_OVER_NONE)
+ || ((step_range_end == 1)
+ && in_prologue (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
("stepi"). Just stop. */
+ /* 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;
print_stop_reason (END_STEPPING_RANGE, 0);
stop_stepping (ecs);
/* Print a message only if not in the middle of doing a "step n"
operation for n > 1 */
if (!step_multi || !stop_step)
- if (interpreter_p && strcmp (interpreter_p, "mi") == 0)
+ if (ui_out_is_mi_like_p (uiout))
ui_out_field_string (uiout, "reason", "end-stepping-range");
#endif
break;
/* The inferior was terminated by a signal. */
#ifdef UI_OUT
annotate_signalled ();
- if (interpreter_p && strcmp (interpreter_p, "mi") == 0)
+ if (ui_out_is_mi_like_p (uiout))
ui_out_field_string (uiout, "reason", "exited-signalled");
ui_out_text (uiout, "\nProgram terminated with signal ");
annotate_signal_name ();
annotate_exited (stop_info);
if (stop_info)
{
- if (interpreter_p && strcmp (interpreter_p, "mi") == 0)
+ if (ui_out_is_mi_like_p (uiout))
ui_out_field_string (uiout, "reason", "exited");
ui_out_text (uiout, "\nProgram exited with code ");
ui_out_field_fmt (uiout, "exit-code", "0%o", (unsigned int) stop_info);
}
else
{
- if (interpreter_p && strcmp (interpreter_p, "mi") == 0)
+ if (ui_out_is_mi_like_p (uiout))
ui_out_field_string (uiout, "reason", "exited-normally");
ui_out_text (uiout, "\nProgram exited normally.\n");
}
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", "signal-received");
ui_out_field_string (uiout, "signal-name", target_signal_to_name (stop_info));
annotate_signal_name_end ();
ui_out_text (uiout, ", ");
#ifdef UI_OUT
/* For mi, have the same behavior every time we stop:
print everything but the source line. */
- if (interpreter_p && strcmp (interpreter_p, "mi") == 0)
+ if (ui_out_is_mi_like_p (uiout))
source_flag = LOC_AND_ADDRESS;
#endif
#ifdef UI_OUT
- if (interpreter_p && strcmp (interpreter_p, "mi") == 0)
+ if (ui_out_is_mi_like_p (uiout))
ui_out_field_int (uiout, "thread-id",
pid_to_thread_id (inferior_ptid));
#endif
select_frame (get_current_frame (), 0);
}
-
- TUIDO (((TuiOpaqueFuncPtr) tui_vCheckDataValues, selected_frame));
-
done:
annotate_stopped ();
}