i386.h (machine_function): New fields use_fast_prologue_epilogue.

i386.h (machine_function): New fields use_fast_prologue_epilogue.

	* i386.h (machine_function): New fields use_fast_prologue_epilogue.
	* i386.c (use_fast_prologue_epilogue): Remove.
	(ix86_frame): New field save_regs-using_mov;
	(ix86_compute_frame_layout):  Decide on fast prologues;
	allocate saved registers in red zone.
	(ix86_expand_epilogue, ix86_expand_prolgoues): Obey new parameters.

From-SVN: r64579