[APX_EGPR] Initial support for APX_F

[APX_EGPR] Initial support for APX_F

Add -mapx-features= enumeration to separate subfeatures of APX_F.
-mapxf is treated same as previous ISA flag, while it sets
-mapx-features=apx_all that enables all subfeatures.

gcc/ChangeLog:

	* common/config/i386/cpuinfo.h (XSTATE_APX_F): New macro.
	(XCR_APX_F_ENABLED_MASK): Likewise.
	(get_available_features): Detect APX_F under
	* common/config/i386/i386-common.cc (OPTION_MASK_ISA2_APX_F_SET): New.
	(OPTION_MASK_ISA2_APX_F_UNSET): Likewise.
	(ix86_handle_option): Handle -mapxf.
	* common/config/i386/i386-cpuinfo.h (FEATURE_APX_F): New.
	* common/config/i386/i386-isas.h: Add entry for APX_F.
	* config/i386/cpuid.h (bit_APX_F): New.
	* config/i386/i386.h (bit_APX_F): (TARGET_APX_EGPR,
	TARGET_APX_PUSH2POP2, TARGET_APX_NDD): New define.
	* config/i386/i386-opts.h (enum apx_features): New enum.
	* config/i386/i386-isa.def (APX_F): New DEF_PTA.
	* config/i386/i386-options.cc (ix86_function_specific_save):
	Save ix86_apx_features.
	(ix86_function_specific_restore): Restore it.
	(ix86_valid_target_attribute_inner_p): Add mapxf.
	(ix86_option_override_internal): Set ix86_apx_features for PTA
	and TARGET_APX_F. Also reports error when APX_F is set but not
	having TARGET_64BIT.
	* config/i386/i386.opt: (-mapxf): New ISA flag option.
	(-mapx=): New enumeration option.
	(apx_features): New enum type.
	(apx_none): New enum value.
	(apx_egpr): Likewise.
	(apx_push2pop2): Likewise.
	(apx_ndd): Likewise.
	(apx_all): Likewise.
	* doc/invoke.texi: Document mapxf.

gcc/testsuite/ChangeLog:

	* gcc.target/i386/apx-1.c: New test.

Co-authored-by: Hongyu Wang <hongyu.wang@intel.com>
Co-authored-by: Hongtao Liu <hongtao.liu@intel.com>