[PATCH 04/18] Make thread_still_needs_step_over consider stepping_over_watchpoint too

Pedro Alves
2015-05-21T23:19:23Z

I noticed that even though keep_going knows to start a step over for a
watchpoint, thread_still_needs_step_over forgets it.

gdb/ChangeLog:
2015-05-21 Pedro Alves <palves@redhat.com>

* infrun.c (thread_still_needs_step_over): Rename to ...
(thread_still_needs_step_over_bp): ... this.
(enum step_over_what): New.
(thread_still_needs_step_over): Reimplement.
---
gdb/infrun.c | 43 +++++++++++++++++++++++++++++++++++++++----
1 file changed, 39 insertions(+), 4 deletions(-)

diff --git a/gdb/infrun.c b/gdb/infrun.c
index cce021d..b97d6e8 100644
--- a/gdb/infrun.c
+++ b/gdb/infrun.c
@@ -1215,6 +1215,19 @@ follow_exec (ptid_t ptid, char *execd_pathname)
matically get reset there in the new process.). */
}

+/* Bit flags indicating what the thread needs to step over. */
+
+enum step_over_what
+ {
+ /* Step over a breakpoint. */
+ STEP_OVER_BREAKPOINT = 1,
+
+ /* Step past a non-continuable watchpoint, in order to let the
+ instruction execute so we can evaluate the watchpoint
+ expression. */
+ STEP_OVER_WATCHPOINT = 2
+ };
+
/* Info about an instruction that is being stepped over. */

struct step_over_info
@@ -2505,7 +2518,7 @@ clear_proceed_status (int step)
meanwhile, we can skip the whole step-over dance. */

static int
-thread_still_needs_step_over (struct thread_info *tp)
+thread_still_needs_step_over_bp (struct thread_info *tp)
{
if (tp->stepping_over_breakpoint)
{
@@ -2522,6 +2535,26 @@ thread_still_needs_step_over (struct thread_info *tp)
return 0;
}

+/* Check whether thread TP still needs to start a step-over in order
+ to make progress when resumed. Returns an bitwise or of enum
+ step_over_what bits, indicating what needs to be stepped over. */
+
+static int
+thread_still_needs_step_over (struct thread_info *tp)
+{
+ struct inferior *inf = find_inferior_ptid (tp->ptid);
+ int what = 0;
+
+ if (thread_still_needs_step_over_bp (tp))
+ what |= STEP_OVER_BREAKPOINT;
+
+ if (tp->stepping_over_watchpoint
+ && !target_have_steppable_watchpoint)
+ what |= STEP_OVER_WATCHPOINT;
+
+ return what;
+}
+
/* Returns true if scheduler locking applies. STEP indicates whether
we're about to do a step/next-like command to a thread. */

@@ -6279,6 +6312,7 @@ keep_going (struct execution_control_state *ecs)
struct regcache *regcache = get_current_regcache ();
int remove_bp;
int remove_wps;
+ enum step_over_what step_what;

/* Either the trap was not expected, but we are continuing
anyway (if we got a signal, the user asked it be passed to
@@ -6299,10 +6333,11 @@ keep_going (struct execution_control_state *ecs)
instruction, and then re-insert the breakpoint when that step
is finished. */

+ step_what = thread_still_needs_step_over (ecs->event_thread);
+
remove_bp = (ecs->hit_singlestep_breakpoint
- || thread_still_needs_step_over (ecs->event_thread));
- remove_wps = (ecs->event_thread->stepping_over_watchpoint
- && !target_have_steppable_watchpoint);
+ || (step_what & STEP_OVER_BREAKPOINT));
+ remove_wps = (step_what & STEP_OVER_WATCHPOINT);

/* We can't use displaced stepping if we need to step past a
watchpoint. The instruction copied to the scratch pad would
--
1.9.3