Optimize -mstackrealign.

Optimize -mstackrealign.

gcc/

2009-10-30  H.J. Lu  <hongjiu.lu@intel.com>

	PR target/40836
	* cfgexpand.c (expand_stack_alignment): Call update_stack_boundary
	first.  Move assert on stack_alignment_estimated just before
	setting stack_realign_needed.
	(gimple_expand_cfg): Initialize stack_alignment_estimated to 0.
	Don't call update_stack_boundary.

	* config/i386/i386.c (ix86_minimum_incoming_stack_boundary): New.
	(verride_options): Don't check ix86_force_align_arg_pointer here.
	(ix86_function_ok_for_sibcall): Use it.
	(ix86_update_stack_boundary): Likewise.

	* config/i386/i386.h (STACK_REALIGN_DEFAULT): Update comments.

gcc/testsuite/

2009-10-30  H.J. Lu  <hongjiu.lu@intel.com>

	PR target/40838
	* gcc.target/i386/incoming-6.c: New.
	* gcc.target/i386/incoming-7.c: Likewise.
	* gcc.target/i386/incoming-8.c: Likewise.
	* gcc.target/i386/incoming-9.c: Likewise.
	* gcc.target/i386/incoming-10.c: Likewise.
	* gcc.target/i386/incoming-11.c: Likewise.
	* gcc.target/i386/incoming-12.c: Likewise.
	* gcc.target/i386/incoming-13.c: Likewise.
	* gcc.target/i386/incoming-14.c: Likewise.
	* gcc.target/i386/incoming-15.c: Likewise.
	* gcc.target/i386/pr37843-4.c: Likewise.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@153750 138bc75d-0d04-0410-961f-82ee72b054a4