md.texi (Defining Attributes): Document that we are defining HAVE_ATTR_name macors as 1 for defined attributes...

	* doc/md.texi (Defining Attributes): Document that we are defining
	HAVE_ATTR_name macors as 1 for defined attributes, and as 0
	for undefined special attributes.
	* final.c (asm_insn_count, align_fuzz): Always define.
	(insn_current_reference_address): Likewise.
	(init_insn_lengths): Use if (HAVE_ATTR_length) instead of
	#ifdef HAVE_ATTR_length.
	(get_attr_length_1, shorten_branches, final): Likewise.
	(final_scan_insn, output_asm_name): Likewise.
	* genattr.c (gen_attr): Define HAVE_ATTR_name macros for
	defined attributes as 1.
	Remove ancient get_attr_alternative compatibility code.
	For special purpose attributes not provided, define HAVE_ATTR_name
	as 0.
	In case no length attribute is given, provide stub definitions
	for insn_*_length* functions, and also include insn-addr.h.
	In case no enabled attribute is given, provide stub definition.
	* genattrtab.c (write_length_unit_log): Always write a definition.
	* hooks.c (hook_int_rtx_1, hook_int_rtx_unreachable): New functions.
	* hooks.h (hook_int_rtx_1, hook_int_rtx_unreachable): Declare.
	* lra-int.h (struct lra_insn_recog_data): Make member
	alternative_enabled_p unconditional.
	* lra.c (free_insn_recog_data): Use if (HAVE_ATTR_length) instead of
	#ifdef HAVE_ATTR_length.
	(lra_set_insn_recog_data): Likewise.  Make initialization of
	alternative_enabled_p unconditional.
	(lra_update_insn_recog_data): Use #if instead of #ifdef for
	HAVE_ATTR_enabled.
	* recog.c [!HAVE_ATTR_enabled] (get_attr_enabled): Don't define.
	(extract_insn): Check HAVE_ATTR_enabled.
	(gate_handle_split_before_regstack): Use #if instead of
	#if defined for HAVE_ATTR_length.

From-SVN: r193168