Re: [patch] circ.exp

[Pedro Alves <palves at redhat dot com>]

On 04/17/2013 10:18 PM, Pedro Alves wrote:

> I see.  The issue is that when haven't collected any registers in the
> the tracepoint (collect $regs), we end up with a frames that are
> un-unwindable (UNWIND_UNAVAILABLE).  All frames in that case have the same
> id (outer_frame_id), even if they represent different functions.  I started
> out with a local fix in tfind_1, but that got ugly quick.

Below's that version.  It feels very much like a workaround.
outer_frame_id should die.

> I think we should fix this in the frame machinery itself.

---

 gdb/tracepoint.c |   30 +++++++++++++++++++++++++++---
 1 file changed, 27 insertions(+), 3 deletions(-)

diff --git a/gdb/tracepoint.c b/gdb/tracepoint.c
index 4113999..fa2ce5d 100644
--- a/gdb/tracepoint.c
+++ b/gdb/tracepoint.c
@@ -2270,6 +2270,9 @@ tfind_1 (enum trace_find_type type, int num,
   struct frame_id old_frame_id = null_frame_id;
   struct tracepoint *tp;
   struct ui_out *uiout = current_uiout;
+  enum unwind_stop_reason old_frame_stop_reason = UNWIND_NO_REASON;
+  int old_frame_func_pc_p = 0;
+  CORE_ADDR old_frame_func_pc;
 
   /* Only try to get the current stack frame if we have a chance of
      succeeding.  In particular, if we're trying to get a first trace
@@ -2279,7 +2282,17 @@ tfind_1 (enum trace_find_type type, int num,
      trace frame.  */
   if (!(type == tfind_number && num == -1)
       && (has_stack_frames () || traceframe_number >= 0))
-    old_frame_id = get_frame_id (get_current_frame ());
+    {
+      struct frame_info *frame = get_current_frame ();
+
+      old_frame_id = get_frame_id (frame);
+
+      get_prev_frame (frame);
+      old_frame_stop_reason = get_frame_unwind_stop_reason (frame);
+
+      old_frame_func_pc_p = get_frame_func_if_available (frame,
+							 &old_frame_func_pc);
+    }
 
   target_frameno = target_trace_find (type, num, addr1, addr2,
 				      &target_tracept);
@@ -2384,8 +2397,19 @@ tfind_1 (enum trace_find_type type, int num,
          function and it's arguments) -- otherwise we'll just show the
          new source line.  */
 
-      if (frame_id_eq (old_frame_id,
-		       get_frame_id (get_current_frame ())))
+      struct frame_info *frame = get_current_frame ();
+      CORE_ADDR frame_func_pc;
+
+      get_prev_frame (frame);
+
+      if ((old_frame_stop_reason == UNWIND_UNAVAILABLE
+	   || get_frame_unwind_stop_reason (frame) == UNWIND_UNAVAILABLE)
+	  && ((old_frame_func_pc_p
+	       != get_frame_func_if_available (frame, &frame_func_pc))
+	      || old_frame_func_pc != frame_func_pc))
+	print_what = SRC_AND_LOC;
+      else if (frame_id_eq (old_frame_id,
+			    get_frame_id (get_current_frame ())))
 	print_what = SRC_LINE;
       else
 	print_what = SRC_AND_LOC;