2003-01-18 Andrew Cagney <ac131313@redhat.com>

* dummy-frame.h (dummy_frame_id_unwind): Delete declaration.
	(dummy_frame_pc_unwind, dummy_frame_register_unwind): Ditto.
	(struct frame_unwind): Declare opaque.
	(dummy_frame_p): Declare function.
	* dummy-frame.c (dummy_frame_id_unwind): Make static.
	(dummy_frame_pc_unwind, dummy_frame_register_unwind): Ditto.
	* dummy-frame.c: Include "frame-unwind.h".
	(dummy_frame_p): New function.
	(dummy_frame_unwind): New variable.
	* frame.c: Include "frame-unwind.h".
	(frame_pc_unwind, frame_id_unwind, frame_register_unwind): Update
	to use the new unwind field.
	(set_unwind_by_pc): Delete function.
	(create_new_frame, get_prev_frame): Set unwind field using
	frame_unwind_find_by_pc.
	(trad_frame_unwind, trad_frame_unwinder): New variables.
	* frame.h (trad_frame_unwind): Declare variable.
	(frame_id_unwind_ftype): Delete declaration.
	(frame_pc_unwind_ftype, frame_register_unwind_ftype): Ditto.
	(struct frame_unwind): Declare opaque.
	(struct frame_info): Replace the fields id_unwind, pc_unwind and
	register_unwind with a single unwind pointer.
	* frame-unwind.h, frame-unwind.c: New files.
	* Makefile.in (SFILES): Add frame-unwind.c.
	(frame_unwind_h): Define.
	(COMMON_OBS): Add frame-unwind.o.
	(frame-unwind.o): Specify dependencies.
	(frame.o, dummy-frame.o): Update dependencies.

gdb/frame-unwind.h

@@ -0,0 +1,96 @@
+/* Definitions for a frame unwinder, for GDB, the GNU debugger.
+
+   Copyright 2003 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#if !defined (FRAME_UNWIND_H)
+#define FRAME_UNWIND_H 1
+
+struct frame_info;
+struct frame_id;
+struct frame_unwind;
+struct gdbarch;
+struct regcache;
+
+/* Return the frame unwind methods for the function that contains PC,
+   or NULL if this this unwinder can't handle this frame.  */
+
+typedef const struct frame_unwind *(frame_unwind_p_ftype) (CORE_ADDR pc);
+
+/* Add a frame unwinder to the list.  The predicates are polled in the
+   order that they are appended.  The initial list contains the dummy
+   frame's predicate.  */
+
+extern void frame_unwind_append_predicate (struct gdbarch *gdbarch,
+					   frame_unwind_p_ftype *p);
+
+/* Iterate through the list of frame unwinders until one returns an
+   implementation.  */
+
+extern const struct frame_unwind *frame_unwind_find_by_pc (struct gdbarch
+							   *gdbarch,
+							   CORE_ADDR pc);
+
+/* Return the location (and possibly value) of REGNUM for the previous
+   (older, up) frame.  All parameters except VALUEP can be assumed to
+   be non NULL.  When VALUEP is NULL, just the location of the
+   register should be returned.
+
+   UNWIND_CACHE is provided as mechanism for implementing a per-frame
+   local cache.  It's initial value being NULL.  Memory for that cache
+   should be allocated using frame_obstack_zalloc().
+
+   Register window architectures (eg SPARC) should note that REGNUM
+   identifies the register for the previous frame.  For instance, a
+   request for the value of "o1" for the previous frame would be found
+   in the register "i1" in this FRAME.  */
+
+typedef void (frame_unwind_reg_ftype) (struct frame_info * frame,
+				       void **unwind_cache,
+				       int regnum,
+				       int *optimized,
+				       enum lval_type * lvalp,
+				       CORE_ADDR *addrp,
+				       int *realnump, void *valuep);
+
+/* Same as for registers above, but return the address at which the
+   calling frame would resume.  */
+
+typedef CORE_ADDR (frame_unwind_pc_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 void (frame_unwind_id_ftype) (struct frame_info * frame,
+				      void **unwind_cache,
+				      struct frame_id * id);
+
+
+struct frame_unwind
+{
+  /* Should the frame's type go here? */
+  /* Should an attribute indicating the frame's address-in-block go
+     here?  */
+  frame_unwind_pc_ftype *pc;
+  frame_unwind_id_ftype *id;
+  frame_unwind_reg_ftype *reg;
+};
+
+#endif