* dwarf2out.c (reg_number): Abort if pseudo.
	(reg_loc_descriptor): Return 0 if pseudo.
	(is_based_loc): Return 0 if pseudo.
	(mem_loc_descriptor): Return 0 for pseudo and handle 0 return from
	recursive calls.
	(concat_loc_descriptor): Return 0 if either part's descriptor is 0.
	(loc_descriptor): Return 0 if can't find location and handle 0
	return from recursive calls.
	(loc_descriptor_from_tree): Likewise.
	Fix handling of indirect.
	Also return 0 for PLACEHOLDER_EXPR.
	Clean up COMPONENT_REF cases.
	(add_AT_location_descriptor): Simplify, but handle 0 return from
	loc_descriptor.
	(add_const_value_attribute): Avoid shift count warning.
	(add_bound_info): Remove test for PLACEHOLDER_EXPR here.
	Set comp_unit_die as context if not in function.

From-SVN: r46573