Support Intel SM4

Support Intel SM4

gcc/ChangeLog:

	* common/config/i386/cpuinfo.h (get_available_features):
	Detech SM4.
	* common/config/i386/i386-common.cc (OPTION_MASK_ISA2_SM4_SET,
	OPTION_MASK_ISA2_SM4_UNSET): New.
	(OPTION_MASK_ISA2_AVX_UNSET): Add SM4.
	(ix86_handle_option): Handle -msm4.
	* common/config/i386/i386-cpuinfo.h (enum processor_features):
	Add FEATURE_SM4.
	* common/config/i386/i386-isas.h: Add ISA_NAME_TABLE_ENTRY for
	sm4.
	* config.gcc: Add sm4intrin.h.
	* config/i386/cpuid.h (bit_SM4): New.
	* config/i386/i386-builtin.def (BDESC): Add new builtins.
	* config/i386/i386-c.cc (ix86_target_macros_internal): Define
	__SM4__.
	* config/i386/i386-isa.def (SM4): Add DEF_PTA(SM4).
	* config/i386/i386-options.cc (isa2_opts): Add -msm4.
	(ix86_valid_target_attribute_inner_p): Handle sm4.
	* config/i386/i386.opt: Add option -msm4.
	* config/i386/immintrin.h: Include sm4intrin.h
	* config/i386/sse.md (vsm4key4_<mode>): New define insn.
	(vsm4rnds4_<mode>): Ditto.
	* doc/extend.texi: Document sm4.
	* doc/invoke.texi: Document -msm4.
	* doc/sourcebuild.texi: Document target sm4.
	* config/i386/sm4intrin.h: New file.

gcc/testsuite/ChangeLog:

	* g++.dg/other/i386-2.C: Add -msm4.
	* g++.dg/other/i386-3.C: Ditto.
	* gcc.target/i386/funcspec-56.inc: Add new target attribute.
	* gcc.target/i386/sse-12.c: Add -msm4.
	* gcc.target/i386/sse-13.c: Ditto.
	* gcc.target/i386/sse-14.c: Ditto.
	* gcc.target/i386/sse-22.c: Add sm4.
	* gcc.target/i386/sse-23.c: Ditto.
	* lib/target-supports.exp (check_effective_target_sm4): New.
	* gcc.target/i386/sm4-1.c: New test.
	* gcc.target/i386/sm4-check.h: Ditto.
	* gcc.target/i386/sm4key4-2.c: Ditto.
	* gcc.target/i386/sm4rnds4-2.c: Ditto.