Add -mavx2.

2011-08-18  Kirill Yukhin  <kirill.yukhin@intel.com>

	* common/config/i386/i386-common.c (OPTION_MASK_ISA_AVX2_SET): New.
	(OPTION_MASK_ISA_AVX_UNSET): Update.
	(OPTION_MASK_ISA_AVX2_UNSET): New.
	(ix86_handle_option): Handle OPT_mavx2 case.
	* config/i386/cpuid.h (bit_AVX2): New.
	* config/i386/driver-i386.c (host_detect_local_cpu): Detect
	AVX2 feature.
	* config/i386/i386-c.c (ix86_target_macros_internal):
	Conditionally define __AVX2__.
	* config/i386/i386.c (ix86_option_override_internal): Define
	PTA_AVX2.  Define "core-avx2" processor alias.  Handle avx2
	option.
	(ix86_valid_target_attribute_inner_p): Handle avx2 option.
	* config/i386/i386.h (TARGET_AVX2): New.
	* config/i386/i386.opt (mavx2): New.
	* doc/invoke.texi: Document -mavx2.

From-SVN: r177876