2002-12-13 Andrew Cagney <ac131313@redhat.com>

	* frame.h (frame_id_unwind): Declare.
	(struct frame_info): Add fields id_unwind, id_unwind_cache_p and
	id_unwind_cache.
	(frame_id_unwind_ftype): Declare.
	* frame.c (frame_id_unwind): New function.
	(set_unwind_by_pc): Add unwind_id parameter.  Initialized.
	(create_new_frame, get_prev_frame): Pass id_unwind to
	set_unwind_by_pc.
	(frame_saved_regs_id_unwind): New function.
	(frame_saved_regs_id_unwind): New function.
	* dummy-frame.c (dummy_frame_id_unwind): New function.
	(struct dummy_frame): Add field id.
	(generic_push_dummy_frame): Initialize `id'.
	* dummy-frame.h (dummy_frame_id_unwind): Declare.

5 files changed, 137 insertions, 3 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index f789563..bd4af6a 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,22 @@
 2002-12-13  Andrew Cagney  <ac131313@redhat.com>
 
+	* frame.h (frame_id_unwind): Declare.
+	(struct frame_info): Add fields id_unwind, id_unwind_cache_p and
+	id_unwind_cache.
+	(frame_id_unwind_ftype): Declare.
+	* frame.c (frame_id_unwind): New function.
+	(set_unwind_by_pc): Add unwind_id parameter.  Initialized.
+	(create_new_frame, get_prev_frame): Pass id_unwind to
+	set_unwind_by_pc.
+	(frame_saved_regs_id_unwind): New function.
+	(frame_saved_regs_id_unwind): New function.
+	* dummy-frame.c (dummy_frame_id_unwind): New function.
+	(struct dummy_frame): Add field id.
+	(generic_push_dummy_frame): Initialize `id'.
+	* dummy-frame.h (dummy_frame_id_unwind): Declare.
+
+2002-12-13  Andrew Cagney  <ac131313@redhat.com>
+
 	* infcmd.c (run_stack_dummy): Create a frame ID directly and then
 	pass that to set_momentary_breakpoint.  Move comments to where they
 	belong.
diff --git a/gdb/dummy-frame.c b/gdb/dummy-frame.c
index deed9c3..fab10c0 100644
--- a/gdb/dummy-frame.c
+++ b/gdb/dummy-frame.c
@@ -43,6 +43,7 @@ struct dummy_frame
   CORE_ADDR fp;
   CORE_ADDR sp;
   CORE_ADDR top;
+  struct frame_id id;
   struct regcache *regcache;
 
   /* Address range of the call dummy code.  Look for PC in the range
@@ -232,6 +233,7 @@ generic_push_dummy_frame (void)
   dummy_frame->sp = read_sp ();
   dummy_frame->top = 0;
   dummy_frame->fp = fp;
+  dummy_frame->id = get_frame_id (get_current_frame ());
   regcache_cpy (dummy_frame->regcache, current_regcache);
   dummy_frame->next = dummy_frame_stack;
   dummy_frame_stack = dummy_frame;
@@ -342,3 +344,17 @@ dummy_frame_pc_unwind (struct frame_info *frame,
   return dummy->pc;
 }
 
+
+struct frame_id
+dummy_frame_id_unwind (struct frame_info *frame,
+		       void **cache)
+{
+  struct dummy_frame *dummy = cached_find_dummy_frame (frame, cache);
+  /* Oops!  In a dummy-frame but can't find the stack dummy.  Pretend
+     that the frame doesn't unwind.  Should this function instead
+     return a has-no-caller indication?  */
+  if (dummy == NULL)
+    return null_frame_id;
+  return dummy->id;
+}
+
diff --git a/gdb/dummy-frame.h b/gdb/dummy-frame.h
index 7f3aee8..cfa2709 100644
--- a/gdb/dummy-frame.h
+++ b/gdb/dummy-frame.h
@@ -60,6 +60,12 @@ extern void dummy_frame_register_unwind (struct frame_info *frame,
 extern CORE_ADDR dummy_frame_pc_unwind (struct frame_info *frame,
 					void **unwind_cache);
 
+/* Assuming that FRAME is a dummy, return the ID of the calling frame
+   (the frame that the dummy has the saved state of).  */
+
+extern struct frame_id dummy_frame_id_unwind (struct frame_info *frame,
+					      void **unwind_cache);
+
 /* Does the PC fall in a dummy frame?
 
    This function is used by "frame.c" when creating a new `struct
diff --git a/gdb/frame.c b/gdb/frame.c
index 29ebfbe..b23d517 100644
--- a/gdb/frame.c
+++ b/gdb/frame.c
@@ -133,6 +133,19 @@ frame_pc_unwind (struct frame_info *frame)
   return frame->pc_unwind_cache;
 }
 
+struct frame_id
+frame_id_unwind (struct frame_info *frame)
+{
+  if (!frame->id_unwind_cache_p)
+    {
+      frame->id_unwind_cache =
+	frame->id_unwind (frame, &frame->unwind_cache);
+      frame->id_unwind_cache_p = 1;
+    }
+  return frame->id_unwind_cache;
+}
+
+
 void
 frame_register_unwind (struct frame_info *frame, int regnum,
 		       int *optimizedp, enum lval_type *lvalp,
@@ -632,6 +645,68 @@ frame_saved_regs_pc_unwind (struct frame_info *frame, void **cache)
   return FRAME_SAVED_PC (frame);
 }
 	
+static struct frame_id
+frame_saved_regs_id_unwind (struct frame_info *next_frame, void **cache)
+{
+  int fromleaf;
+  struct frame_id id;
+
+  if (next_frame->next == NULL)
+    /* FIXME: 2002-11-09: Frameless functions can occure anywhere in
+       the frame chain, not just the inner most frame!  The generic,
+       per-architecture, frame code should handle this and the below
+       should simply be removed.  */
+    fromleaf = FRAMELESS_FUNCTION_INVOCATION (next_frame);
+  else
+    fromleaf = 0;
+
+  if (fromleaf)
+    /* A frameless inner-most frame.  The `FP' (which isn't an
+       architecture frame-pointer register!) of the caller is the same
+       as the callee.  */
+    /* FIXME: 2002-11-09: There isn't any reason to special case this
+       edge condition.  Instead the per-architecture code should hande
+       it locally.  */
+    id.base = get_frame_base (next_frame);
+  else
+    {
+      /* Two macros defined in tm.h specify the machine-dependent
+         actions to be performed here.
+
+         First, get the frame's chain-pointer.
+
+         If that is zero, the frame is the outermost frame or a leaf
+         called by the outermost frame.  This means that if start
+         calls main without a frame, we'll return 0 (which is fine
+         anyway).
+
+         Nope; there's a problem.  This also returns when the current
+         routine is a leaf of main.  This is unacceptable.  We move
+         this to after the ffi test; I'd rather have backtraces from
+         start go curfluy than have an abort called from main not show
+         main.  */
+      id.base = FRAME_CHAIN (next_frame);
+
+      /* FIXME: cagney/2002-06-08: There should be two tests here.
+         The first would check for a valid frame chain based on a user
+         selectable policy.  The default being ``stop at main'' (as
+         implemented by generic_func_frame_chain_valid()).  Other
+         policies would be available - stop at NULL, ....  The second
+         test, if provided by the target architecture, would check for
+         more exotic cases - most target architectures wouldn't bother
+         with this second case.  */
+      if (!FRAME_CHAIN_VALID (id.base, next_frame))
+	return null_frame_id;
+    }
+  if (id.base == 0)
+    return null_frame_id;
+
+  /* FIXME: cagney/2002-06-08: This should probably return the frame's
+     function and not the PC (a.k.a. resume address).  */
+  id.pc = frame_pc_unwind (next_frame);
+  return id;
+}
+	
 /* Function: get_saved_register
    Find register number REGNUM relative to FRAME and put its (raw,
    target format) contents in *RAW_BUFFER.  
@@ -736,7 +811,8 @@ deprecated_generic_get_saved_register (char *raw_buffer, int *optimized,
 static void
 set_unwind_by_pc (CORE_ADDR pc, CORE_ADDR fp,
 		  frame_register_unwind_ftype **unwind_register,
-		  frame_pc_unwind_ftype **unwind_pc)
+		  frame_pc_unwind_ftype **unwind_pc,
+		  frame_id_unwind_ftype **unwind_id)
 {
   if (!DEPRECATED_USE_GENERIC_DUMMY_FRAMES)
     {
@@ -746,6 +822,7 @@ set_unwind_by_pc (CORE_ADDR pc, CORE_ADDR fp,
 	 return vaguely correct values..  */
       *unwind_register = frame_saved_regs_register_unwind;
       *unwind_pc = frame_saved_regs_pc_unwind;
+      *unwind_id = frame_saved_regs_id_unwind;
     }
   else if (DEPRECATED_PC_IN_CALL_DUMMY_P ()
 	   ? DEPRECATED_PC_IN_CALL_DUMMY (pc, 0, 0)
@@ -753,11 +830,13 @@ set_unwind_by_pc (CORE_ADDR pc, CORE_ADDR fp,
     {
       *unwind_register = dummy_frame_register_unwind;
       *unwind_pc = dummy_frame_pc_unwind;
+      *unwind_id = dummy_frame_id_unwind;
     }
   else
     {
       *unwind_register = frame_saved_regs_register_unwind;
       *unwind_pc = frame_saved_regs_pc_unwind;
+      *unwind_id = frame_saved_regs_id_unwind;
     }
 }
 
@@ -809,7 +888,7 @@ create_new_frame (CORE_ADDR addr, CORE_ADDR pc)
 
   /* Select/initialize an unwind function.  */
   set_unwind_by_pc (fi->pc, fi->frame, &fi->register_unwind,
-		    &fi->pc_unwind);
+		    &fi->pc_unwind, &fi->id_unwind);
 
   return fi;
 }
@@ -1064,7 +1143,7 @@ get_prev_frame (struct frame_info *next_frame)
      check things like the debug info at that point (dwarf2cfi?) and
      use that to decide how the frame should be unwound.  */
   set_unwind_by_pc (prev->pc, prev->frame, &prev->register_unwind,
-		    &prev->pc_unwind);
+		    &prev->pc_unwind, &prev->id_unwind);
 
   /* NOTE: cagney/2002-11-18: The code segments, found in
      create_new_frame and get_prev_frame(), that initializes the
diff --git a/gdb/frame.h b/gdb/frame.h
index 5a45502..0fd305e 100644
--- a/gdb/frame.h
+++ b/gdb/frame.h
@@ -298,6 +298,10 @@ extern const char *frame_map_regnum_to_name (int regnum);
 
 extern CORE_ADDR frame_pc_unwind (struct frame_info *frame);
 
+/* Unwind the frame ID.  Return an ID that uniquely identifies the
+   caller's frame.  */
+extern struct frame_id frame_id_unwind (struct frame_info *frame);
+
 
 /* Return the location (and possibly value) of REGNUM for the previous
    (older, up) frame.  All parameters except VALUEP can be assumed to
@@ -328,6 +332,12 @@ typedef void (frame_register_unwind_ftype) (struct frame_info *frame,
 typedef CORE_ADDR (frame_pc_unwind_ftype) (struct frame_info *frame,
 					   void **unwind_cache);
 
+/* Same as for registers above, but return the ID of the frame that
+   called this one.  */
+
+typedef struct frame_info (frame_id_unwind_ftype) (struct frame_info *frame,
+						   void **unwind_cache);
+
 /* Describe the saved registers of a frame.  */
 
 #if defined (EXTRA_FRAME_INFO) || defined (FRAME_FIND_SAVED_REGS)
@@ -424,6 +434,12 @@ struct frame_info
     int pc_unwind_cache_p;
     CORE_ADDR pc_unwind_cache;
 
+    /* See description above.  The previous frame's resume address.
+       Save the previous PC in a local cache.  */
+    frame_id_unwind_ftype *id_unwind;
+    int id_unwind_cache_p;
+    struct frame_id id_unwind_cache;
+
     /* Pointers to the next (down, inner, younger) and previous (up,
        outer, older) frame_info's in the frame cache.  */
     struct frame_info *next; /* down, inner, younger */