* dwarf2expr.c (execute_stack_op): Handle DW_OP_GNU_const_index.

	* dwarf2expr.c (execute_stack_op): Handle DW_OP_GNU_const_index.
	Adjust address for DW_OP_GNU_addr_index.
	* dwarf2expr.h (dwarf_expr_context): Update comment.
	* dwarf2loc.c (locexpr_describe_location_piece): New arg per_cu,
	all callers updated.  Handle TLS vars described with
	DW_OP_GNU_const_index.
	(disassemble_dwarf_expression): Handle DW_OP_GNU_addr_index
	and DW_OP_GNU_const_index.
	* dwarf2read.c (decode_locdesc): Handle DW_OP_GNU_addr_index.