2003-04-01 Andrew Cagney <cagney@redhat.com>

	Add frame debug info addresses:
	* frame-base.c: New file.
	* frame-base.h: New file.
	* frame.h (struct frame_base): Add opaque declaration.
	(get_frame_base): Update comment.
	(get_frame_base_address): Declare.
	(get_frame_locals_address): Declare.
	(get_frame_args_address): Declare.
	(struct frame_info): Add "base" and "base_cache".  Update
	comments on the unwinder.
	* frame.c: Include "frame-base.h".
	(get_frame_locals_address): New function.
	(get_frame_base_address): New function.
	(get_frame_args_address): New function.
	* findvar.c (read_var_value): Use get_frame_locals_address and
	get_frame_args_address.
	* stack.c (frame_info): Use get_frame_locals_address and
	get_frame_args_address.
	(FRAME_ARGS_ADDRESS_CORRECT): Delete conditionally defined macro,
	moved to "frame-base.c".
	* printcmd.c (print_frame_nameless_args): Ditto.
	* symtab.h (address_class): Update comments.
	* dwarf2loc.c (dwarf_expr_frame_base): Add note about
	get_frame_base_address.
	* dwarf2expr.c (execute_stack_op): Ditto.
	* Makefile.in (frame_base_h): Define.
	(frame.o): Update dependencies.
	(frame-base.o): Add dependencies.
	(SFILES): Add frame-base.c.
	(COMMON_OBS): Add frame-base.o.

1 files changed, 94 insertions, 0 deletions

diff --git a/gdb/frame-base.h b/gdb/frame-base.h
new file mode 100644
index 00000000000..5e0d5db2e25
--- /dev/null
+++ b/gdb/frame-base.h
@@ -0,0 +1,94 @@
+/* Definitions for a frame base, 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_BASE_H)
+#define FRAME_BASE_H 1
+
+struct frame_info;
+struct frame_id;
+struct frame_unwind;
+struct frame_base;
+struct gdbarch;
+struct regcache;
+
+/* Return the frame base methods for the function that contains PC, or
+   NULL if it can't handle this frame.  */
+
+typedef const struct frame_base *(frame_base_p_ftype) (CORE_ADDR pc);
+
+/* Add a frame base handler to the list.  The predicates are polled in
+   the order that they are appended.  */
+
+extern void frame_base_append_predicate (struct gdbarch *gdbarch,
+					 frame_base_p_ftype *p);
+
+/* Set the default frame base.  If all else fails, this one is
+   returned.  If this isn't set, the default is to use legacy code
+   that uses things like the frame ID's base (ulgh!).  */
+
+extern void frame_base_set_default (struct gdbarch *gdbarch,
+				    const struct frame_base *def);
+
+/* Iterate through the list of frame base handlers until one returns
+   an implementation.  */
+
+extern const struct frame_base *frame_base_find_by_pc (struct gdbarch *gdbarch,
+						       CORE_ADDR pc);
+
+/* Assuming the frame chain: (outer) prev <-> this <-> next (inner);
+   and that this is a `normal frame'; use the NEXT frame, and its
+   register unwind method, to determine the address of THIS frame's
+   `base'.
+
+   The exact meaning of `base' is highly dependant on the type of the
+   debug info.  It is assumed that dwarf2, stabs, ... will each
+   provide their own methods.
+
+   A typical implmentation will return the same value for base,
+   locals-base and args-base.  That value, however, will likely be
+   different to the frame ID's stack address.  */
+
+/* A generic base address.  */
+
+typedef CORE_ADDR (frame_this_base_ftype) (struct frame_info *next_frame,
+					   void **this_base_cache);
+
+/* The base address of the frame's local variables.  */
+
+typedef CORE_ADDR (frame_this_locals_ftype) (struct frame_info *next_frame,
+					     void **this_base_cache);
+
+/* The base address of the frame's arguments / parameters.  */
+
+typedef CORE_ADDR (frame_this_args_ftype) (struct frame_info *next_frame,
+					   void **this_base_cache);
+
+struct frame_base
+{
+  /* If non-NULL, a low-level unwinder that shares its implementation
+     with this high-level frame-base method.  */
+  const struct frame_unwind *unwind;
+  frame_this_base_ftype *this_base;
+  frame_this_locals_ftype *this_locals;
+  frame_this_args_ftype *this_args;
+};
+
+#endif