gdb

	* dwarf2loc.c (struct piece_closure) <arch>: New field.
	(dwarf2_evaluate_loc_desc): Update.
	(dwarf2_loc_desc_needs_frame): Likewise.
	(allocate_piece_closure): Initialize new field.
	(read_pieced_value): Update.
	(write_pieced_value): Update.
	(copy_pieced_value_closure): Update.
	* dwarf2expr.h (enum dwarf_value_location): New.
	(struct dwarf_expr_context) <in_reg>: Remove.
	<location, len, data>: New fields.
	(struct dwarf_expr_piece) <in_reg, value>: Remove.
	<location, v>: New fields.
	* dwarf2expr.c (add_piece): Remove in_reg, value arguments.
	Update.
	(require_composition): New function.
	(execute_stack_op): Update.
	<DW_OP_implicit_value, DW_OP_stack_value>: New cases.
	<DW_OP_reg0>: Set location, not in_reg.
	<DW_OP_regx>: Likewise.  Use require_composition.
	<DW_OP_fbreg>: Update.
	<DW_OP_piece>: Likewise.
	* dwarf2-frame.c (execute_stack_op): Update.
gdb/testsuite
	* gdb.dwarf2/valop.S: New file.
	* gdb.dwarf2/valop.exp: New file.

1 files changed, 8 insertions, 1 deletions

diff --git a/gdb/dwarf2-frame.c b/gdb/dwarf2-frame.c
index f9ca067..a923edf 100644
--- a/gdb/dwarf2-frame.c
+++ b/gdb/dwarf2-frame.c
@@ -379,8 +379,15 @@ execute_stack_op (gdb_byte *exp, ULONGEST len, int addr_size,
   dwarf_expr_eval (ctx, exp, len);
   result = dwarf_expr_fetch (ctx, 0);
 
-  if (ctx->in_reg)
+  if (ctx->location == DWARF_VALUE_REGISTER)
     result = read_reg (this_frame, result);
+  else if (ctx->location != DWARF_VALUE_MEMORY)
+    {
+      /* This is actually invalid DWARF, but if we ever do run across
+	 it somehow, we might as well support it.  So, instead, report
+	 it as unimplemented.  */
+      error (_("Not implemented: computing unwound register using explicit value operator"));
+    }
 
   do_cleanups (old_chain);