Based on a patch from Daniel Berlin (dberlin@dberlin.org).

	* symtab.h: Add opaque declarations of struct axs_value and
	struct agent_expr.
	(enum address_class): Add LOC_COMPUTED and LOC_COMPUTED_ARG.
	(struct location_funcs): New type.
	(struct symbol): Add "loc" to aux_value.
	(SYMBOL_LOCATION_BATON, SYMBOL_LOCATION_FUNCS): New macros.
	* dwarf2read.c: Include "dwarf2expr.h".
	(dwarf2_symbol_mark_computed): New function.
	(read_func_scope): Use it.
	(var_decode_location): New function.
	(new_symbol): Use it.
	* dwarf2expr.c, dwarf2expr.h, dwarf2loc.c, dwarf2loc.h: New files.

	* Makefile.in (SFILES): Add dwarf2loc.c and dwarf2expr.c.
	(dwarf2expr_h, dwarf2loc_h): New variables.
	(COMMON_OBS): Add dwarf2expr.o and dwarf2loc.o.
	(dwarf2expr.o, dwarf2loc.o): New rules.
	(dwarf2read.o): Add $(dwarf2expr_h) and $(dwarf2loc_h).
	* buildsym.c (finish_block): Handle LOC_COMPUTED and
	LOC_COMPUTED_ARG.
	* findvar.c (symbol_read_needs_frame, read_var_value): Likewise.
	* m2-exp.y (yylex): Likewise.
	* printcmd.c (address_info, print_frame_args): Likewise.
	* stack.c (print_block_frame_locals, print_frame_arg_vars): Likewise.
	* symmisc.c (print_symbol, print_partial_symbols): Likewise.
	* ada-lang.c (ada_resolve_subexp, symtab_for_sym)
	(ada_add_block_symbols, fill_in_ada_prototype): Likewise.
	* symtab.c (lookup_block_symbol): Likewise.

1 files changed, 97 insertions, 0 deletions

diff --git a/gdb/dwarf2expr.h b/gdb/dwarf2expr.h
new file mode 100644
index 00000000000..e8cc489dcf6
--- /dev/null
+++ b/gdb/dwarf2expr.h
@@ -0,0 +1,97 @@
+/* Dwarf2 Expression Evaluator
+   Copyright 2001, 2002, 2003 Free Software Foundation, Inc.
+   Contributed by Daniel Berlin (dan@dberlin.org)
+   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 (DWARF2EXPR_H)
+#define DWARF2EXPR_H
+
+/* The expression evaluator works with a dwarf_expr_context, describing
+   its current state and its callbacks.  */
+struct dwarf_expr_context
+{
+  /* The stack of values, allocated with xmalloc.  */
+  CORE_ADDR *stack;
+
+  /* The number of values currently pushed on the stack, and the
+     number of elements allocated to the stack.  */
+  int stack_len, stack_allocated;
+
+  /* An opaque argument provided by the caller, which will be passed
+     to all of the callback functions.  */
+  void *baton;
+
+  /* Return the value of register number REGNUM.  LVALP will be set
+     to the kind of lval this register is (generally lval_register
+     for the current frame's registers or lval_memory for a register
+     saved to the stack).  For lval_memory ADDRP will be set to the
+     saved location of the register.  */
+  CORE_ADDR (*read_reg) (void *baton, int regnum, enum lval_type *lvalp,
+			 CORE_ADDR *addrp);
+
+  /* Read LENGTH bytes at ADDR into BUF.  */
+  void (*read_mem) (void *baton, char *buf, CORE_ADDR addr,
+		    size_t length);
+
+  /* Return the location expression for the frame base attribute, in
+     START and LENGTH.  The result must be live until the current
+     expression evaluation is complete.  */
+  void (*get_frame_base) (void *baton, unsigned char **start,
+			 size_t *length);
+
+  /* Return the thread-local storage address for
+     DW_OP_GNU_push_tls_address.  */
+  CORE_ADDR (*get_tls_address) (void *baton, CORE_ADDR offset);
+
+#if 0
+  /* Not yet implemented.  */
+
+  /* Return the location expression for the dwarf expression
+     subroutine in the die at OFFSET in the current compilation unit.
+     The result must be live until the current expression evaluation
+     is complete.  */
+  unsigned char *(*get_subr) (void *baton, off_t offset, size_t *length);
+
+  /* Return the `object address' for DW_OP_push_object_address.  */
+  CORE_ADDR (*get_object_address) (void *baton);
+#endif
+
+  /* The current depth of dwarf expression recursion, via DW_OP_call*,
+     DW_OP_fbreg, DW_OP_push_object_address, etc., and the maximum
+     depth we'll tolerate before raising an error.  */
+  int recursion_depth, max_recursion_depth;
+
+  /* Non-zero if the result is in a register.  The register number
+     will be in REGNUM, and the result will be the contents of the
+     register.  */
+  int in_reg;
+
+  /* If the result is in a register, the register number.  */
+  int regnum;
+};
+
+struct dwarf_expr_context *new_dwarf_expr_context ();
+void free_dwarf_expr_context (struct dwarf_expr_context *ctx);
+
+void dwarf_expr_push (struct dwarf_expr_context *ctx, CORE_ADDR value);
+void dwarf_expr_pop (struct dwarf_expr_context *ctx);
+void dwarf_expr_eval (struct dwarf_expr_context *ctx, unsigned char *addr,
+		      size_t len);
+CORE_ADDR dwarf_expr_fetch (struct dwarf_expr_context *ctx, int n);
+
+#endif