Support Intel prefetchit0/t1

Support Intel prefetchit0/t1

gcc/ChangeLog:

	* common/config/i386/cpuinfo.h (get_available_features):
	Detect PREFETCHI.
	* common/config/i386/i386-common.cc
	(OPTION_MASK_ISA2_PREFETCHI_SET,
	OPTION_MASK_ISA2_PREFETCHI_UNSET): New.
	(ix86_handle_option): Handle -mprefetchi.
	* common/config/i386/i386-cpuinfo.h
	(enum processor_features): Add FEATURE_PREFETCHI.
	* common/config/i386/i386-isas.h: Add ISA_NAME_TABLE_ENTRY
	for prefetchi.
	* config.gcc: Add prfchiintrin.h.
	* config/i386/cpuid.h (bit_PREFETCHI): New.
	* config/i386/i386-builtin-types.def:
	Add DEF_FUNCTION_TYPE (VOID, PCVOID, INT)
	and DEF_FUNCTION_TYPE (VOID, PCVOID, INT, INT, INT).
	* config/i386/i386-builtin.def (BDESC): Add new builtins.
	* config/i386/i386-c.cc (ix86_target_macros_internal):
	Define __PREFETCHI__.
	* config/i386/i386-expand.cc: Handle new builtins.
	* config/i386/i386-isa.def (PREFETCHI):
	Add DEF_PTA(PREFETCHI).
	* config/i386/i386-options.cc
	(ix86_valid_target_attribute_inner_p): Handle prefetchi.
	* config/i386/i386.md (prefetchi): New define_insn.
	* config/i386/i386.opt: Add option -mprefetchi.
	* config/i386/predicates.md (local_func_symbolic_operand):
	New predicates.
	* config/i386/x86gprintrin.h: Include prfchiintrin.h.
	* config/i386/xmmintrin.h (enum _mm_hint): New enum for
	prefetchi.
	(_mm_prefetch): Handle the highest bit of enum.
	* doc/extend.texi: Document prefetchi.
	* doc/invoke.texi: Document -mprefetchi.
	* doc/sourcebuild.texi: Document target prefetchi.
	* config/i386/prfchiintrin.h: New file.

gcc/testsuite/ChangeLog:

	* g++.dg/other/i386-2.C: Add -mprefetchi.
	* g++.dg/other/i386-3.C: Ditto.
	* gcc.target/i386/avx-1.c: Ditto.
	* gcc.target/i386/funcspec-56.inc: Add new target attribute.
	* gcc.target/i386/sse-13.c: Add -mprefetchi.
	* gcc.target/i386/sse-23.c: Ditto.
	* gcc.target/i386/x86gprintrin-1.c: Ditto.
	* gcc.target/i386/x86gprintrin-2.c: Ditto.
	* gcc.target/i386/x86gprintrin-3.c: Ditto.
	* gcc.target/i386/x86gprintrin-4.c: Ditto.
	* gcc.target/i386/x86gprintrin-5.c: Ditto.
	* gcc.target/i386/prefetchi-1.c: New test.
	* gcc.target/i386/prefetchi-2.c: Ditto.
	* gcc.target/i386/prefetchi-3.c: Ditto.
	* gcc.target/i386/prefetchi-4.c: Ditto.

Co-authored-by: Hongtao Liu <hongtao.liu@intel.com>