* defaults.h (USE_MD_CONSTRAINTS, EXTRA_MEMORY_CONSTRAINT)
	(EXTRA_ADDRESS_CONSTRAINT, DEFAULT_CONSTRAINT_LEN, CONSTRAINT_LEN)
	(CONST_OK_FOR_CONSTRAINT_P, CONST_DOUBLE_OK_FOR_LETTER_P)
	(REG_CLASS_FROM_CONSTRAINT, EXTRA_CONSTRAINT_STR): Delete definitions
	in this file.
	(REG_CLASS_FROM_LETTER, CONST_OK_FOR_LETTER_P)
	(CONST_DOUBLE_OK_FOR_LETTER_P, EXTRA_CONSTRAINT): Move poising to...
	* system.h: ...here and make it unconditional.
	* target.def (conditional_register_usage): Mention
	define_register_constraint instead of old-style constraint macros.
	* doc/tm.texi.in: Remove documentation for old-style constraint macros.
	* doc/tm.texi: Regenerate.
	* genoutput.c: Remove USE_MD_CONSTRAINTS conditions and all code
	protected by !USE_MD_CONSTRAINTS.
	* config/frv/frv.md: Remove quote from old version of documentation.
	* config/frv/frv.c (frv_conditional_register_usage): Likewise.
	* config/m32r/m32r.c (easy_di_const, easy_df_const): Avoid mentioning
	CONST_DOUBLE_OK_FOR_LETTER.
	* config/sh/constraints.md: Likewise EXTRA_CONSTRAINT.

From-SVN: r211161