* dwarf2out.c (debug_str_hash): New.

	* dwarf2out.c (debug_str_hash): New.
	(struct indirect_string_node): New.
	(struct dw_val_struct): Change type of val_str to it.
	(DEBUG_STR_SECTION_FLAGS): Define.
	(add_AT_string): Push string into hashtable, increment reference
	counter.
	(AT_string): Return string from ht_identifier.
	(AT_string_form): New.
	(free_AT): For dw_val_class_str, just decrement reference counter.
	(size_of_string): Remove.
	(size_of_die): Use AT_string_form to decide what size the string
	occupies in DIE.
	(size_of_pubnames): Use strlen instead of size_of_string.
	(value_format): Use AT_string_form for dw_val_class_str.
	(output_die): Output DW_FORM_strp strings using
	dw2_asm_output_offset.
	(indirect_string_alloc, output_indirect_string): New.
	(dwarf2out_finish): Emit .debug_str strings if there are any.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@46858 138bc75d-0d04-0410-961f-82ee72b054a4