[PATCH v9 05/29] frame: add frame_is_tailcall function

[Markus Metzger <markus.t.metzger@intel.com>]

Currently, gdb is looking at the frame type when trying to identify
tailcall frames.  This requires touching several places when adding
a new tailcall frame type.

Add a predicate for tailcall frames.

This patch is no longer needed for the btrace series.  I leave it in
since it might help someone in the future.  I'd also be OK to remove it.

2013-12-19  Markus Metzger  <markus.t.metzger@intel.com>

	* frame.h (frame_is_tailcall): New.
	* frame.c (frame_is_tailcall): New.
	(skip_artificial_frames, frame_pop, get_frame_address_in_block):
	Call frame_is_tailcall.
	* infcmd.c (construct_inferior_arguments): Call frame_is_tailcall.
	* stack.h (frame_info): Call frame_is_tailcall.
	* dwarf2-frame-tailcall.c (frame_is_tailcall): Rename to ..
	(frame_is_dwarf2_tailcall): ... this.
	(cache_find): Update.


---
 gdb/dwarf2-frame-tailcall.c |  4 ++--
 gdb/frame.c                 | 23 +++++++++++++++++------
 gdb/frame.h                 |  7 ++++++-
 gdb/infcmd.c                |  6 +++---
 gdb/stack.c                 |  2 +-
 5 files changed, 29 insertions(+), 13 deletions(-)

diff --git a/gdb/dwarf2-frame-tailcall.c b/gdb/dwarf2-frame-tailcall.c
index b82a051..35de19d 100644
--- a/gdb/dwarf2-frame-tailcall.c
+++ b/gdb/dwarf2-frame-tailcall.c
@@ -140,7 +140,7 @@ cache_unref (struct tailcall_cache *cache)
    return 0.  */
 
 static int
-frame_is_tailcall (struct frame_info *fi)
+frame_is_dwarf2_tailcall (struct frame_info *fi)
 {
   return frame_unwinder_is (fi, &dwarf2_tailcall_frame_unwind);
 }
@@ -154,7 +154,7 @@ cache_find (struct frame_info *fi)
   struct tailcall_cache *cache;
   void **slot;
 
-  while (frame_is_tailcall (fi))
+  while (frame_is_dwarf2_tailcall (fi))
     {
       fi = get_next_frame (fi);
       gdb_assert (fi != NULL);
diff --git a/gdb/frame.c b/gdb/frame.c
index ed31c9e..99c2309 100644
--- a/gdb/frame.c
+++ b/gdb/frame.c
@@ -426,7 +426,7 @@ static struct frame_info *
 skip_artificial_frames (struct frame_info *frame)
 {
   while (get_frame_type (frame) == INLINE_FRAME
-	 || get_frame_type (frame) == TAILCALL_FRAME)
+	 || frame_is_tailcall (frame))
     frame = get_prev_frame (frame);
 
   return frame;
@@ -945,9 +945,9 @@ frame_pop (struct frame_info *this_frame)
   if (!prev_frame)
     error (_("Cannot pop the initial frame."));
 
-  /* Ignore TAILCALL_FRAME type frames, they were executed already before
-     entering THISFRAME.  */
-  while (get_frame_type (prev_frame) == TAILCALL_FRAME)
+  /* Ignore tailcall frames, they were executed already before entering
+     THISFRAME.  */
+  while (frame_is_tailcall (prev_frame))
     prev_frame = get_prev_frame (prev_frame);
 
   /* Make a copy of all the register values unwound from this frame.
@@ -2206,9 +2206,9 @@ get_frame_address_in_block (struct frame_info *this_frame)
     next_frame = next_frame->next;
 
   if ((get_frame_type (next_frame) == NORMAL_FRAME
-       || get_frame_type (next_frame) == TAILCALL_FRAME)
+       || frame_is_tailcall (next_frame))
       && (get_frame_type (this_frame) == NORMAL_FRAME
-	  || get_frame_type (this_frame) == TAILCALL_FRAME
+	  || frame_is_tailcall (this_frame)
 	  || get_frame_type (this_frame) == INLINE_FRAME))
     return pc - 1;
 
@@ -2356,6 +2356,17 @@ frame_unwinder_is (struct frame_info *fi, const struct frame_unwind *unwinder)
   return fi->unwind == unwinder;
 }
 
+/* See frame.h.  */
+
+int
+frame_is_tailcall (struct frame_info *fi)
+{
+  enum frame_type type;
+
+  type = get_frame_type (fi);
+  return type == TAILCALL_FRAME;
+}
+
 /* Level of the selected frame: 0 for innermost, 1 for its caller, ...
    or -1 for a NULL frame.  */
 
diff --git a/gdb/frame.h b/gdb/frame.h
index b03f212..8b6755e 100644
--- a/gdb/frame.h
+++ b/gdb/frame.h
@@ -205,7 +205,7 @@ extern int frame_id_p (struct frame_id l);
 
 /* Returns non-zero when L is a valid frame representing a frame made up by GDB
    without stack data representation in inferior, such as INLINE_FRAME or
-   TAILCALL_FRAME.  */
+   tailcall frames.  */
 extern int frame_id_artificial_p (struct frame_id l);
 
 /* Returns non-zero when L and R identify the same frame, or, if
@@ -789,4 +789,9 @@ extern struct frame_info *create_new_frame (CORE_ADDR base, CORE_ADDR pc);
 extern int frame_unwinder_is (struct frame_info *fi,
 			      const struct frame_unwind *unwinder);
 
+/* Return true if frame FI is a tailcall frame.  */
+
+extern int frame_is_tailcall (struct frame_info *fi);
+
+
 #endif /* !defined (FRAME_H)  */
diff --git a/gdb/infcmd.c b/gdb/infcmd.c
index 19f720b..dd8d06a 100644
--- a/gdb/infcmd.c
+++ b/gdb/infcmd.c
@@ -1776,9 +1776,9 @@ finish_command (char *arg, int from_tty)
       return;
     }
 
-  /* Ignore TAILCALL_FRAME type frames, they were executed already before
-     entering THISFRAME.  */
-  while (get_frame_type (frame) == TAILCALL_FRAME)
+  /* Ignore tailcall frames, they were executed already before entering
+     THISFRAME.  */
+  while (frame_is_tailcall (frame))
     frame = get_prev_frame (frame);
 
   /* Find the function we will return from.  */
diff --git a/gdb/stack.c b/gdb/stack.c
index f45bb80..8007819 100644
--- a/gdb/stack.c
+++ b/gdb/stack.c
@@ -1529,7 +1529,7 @@ frame_info (char *addr_exp, int from_tty)
 	printf_filtered (_(" Outermost frame: %s\n"),
 			 frame_stop_reason_string (reason));
     }
-  else if (get_frame_type (fi) == TAILCALL_FRAME)
+  else if (frame_is_tailcall (fi))
     puts_filtered (" tail call frame");
   else if (get_frame_type (fi) == INLINE_FRAME)
     printf_filtered (" inlined into frame %d",
-- 
1.8.3.1