gdb

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.