* local-alloc.c (local_alloc): Avoid call of update_equiv_regs when not optimizing.

	* toplev.c (rest_of_compilation): Cann mark_constant_function
	only when optimizing.

	* flow.c (calculate_global_regs_live): Ensure that all AUX fields are NULL.

	* cfgcleanup.c (bb_flags): Add BB_NONTHREADABLE_BLOCK.
	(thread_jump): Set BB_NONTHREADABLE_BLOCK, check it.
	(try_optimize_cfg): clear all AUX fields.

	* i386.c (aligned_operand): Be prepared for SUBREGed registers.
	(ix86_decompose_address): Use REG_P instead of GET_CODE (...) == REG.
	(ix86_address_cost): Be prepared for SUBREGed registers.
	(legitimate_address_p): Accept SUBREGed registers.

From-SVN: r51604