+struct dwarf_expr_context;
+
+/* Virtual method table for struct dwarf_expr_context below. */
+
+struct dwarf_expr_context_funcs
+{
+ /* Return the value of register number REGNUM. */
+ CORE_ADDR (*read_reg) (void *baton, int regnum);
+
+ /* Read LENGTH bytes at ADDR into BUF. */
+ void (*read_mem) (void *baton, gdb_byte *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, const gdb_byte **start, size_t *length);
+
+ /* Return the CFA for the frame. */
+ CORE_ADDR (*get_frame_cfa) (void *baton);
+
+ /* Return the PC for the frame. */
+ CORE_ADDR (*get_frame_pc) (void *baton);
+
+ /* Return the thread-local storage address for
+ DW_OP_GNU_push_tls_address. */
+ CORE_ADDR (*get_tls_address) (void *baton, CORE_ADDR offset);
+
+ /* Execute DW_AT_location expression for the DWARF expression subroutine in
+ the DIE at DIE_OFFSET in the CU from CTX. Do not touch STACK while it
+ being passed to and returned from the called DWARF subroutine. */
+ void (*dwarf_call) (struct dwarf_expr_context *ctx, size_t die_offset);
+
+ /* Return the base type given by the indicated DIE. This can throw
+ an exception if the DIE is invalid or does not represent a base
+ type. If can also be NULL in the special case where the
+ callbacks are not performing evaluation, and thus it is
+ meaningful to substitute a stub type of the correct size. */
+ struct type *(*get_base_type) (struct dwarf_expr_context *ctx, size_t die);
+
+#if 0
+ /* Not yet implemented. */
+
+ /* Return the `object address' for DW_OP_push_object_address. */
+ CORE_ADDR (*get_object_address) (void *baton);
+#endif
+};
+