Fix PR82941 and PR82942 by adding proper vzeroupper generation on SKX.

Fix PR82941 and PR82942 by adding proper vzeroupper generation on SKX.

2017-11-15  Sebastian Peryt  <sebastian.peryt@intel.com>

gcc/

	PR target/82941
	PR target/82942
	* config/i386/i386.c (pass_insert_vzeroupper): Modify gate condition
	to return true on Xeon and not on Xeon Phi.
	(ix86_check_avx256_register): Changed to ...
	(ix86_check_avx_upper_register): ... this. Add extra check for
	VALID_AVX512F_REG_OR_XI_MODE.
	(ix86_avx_u128_mode_needed): Changed
	ix86_check_avx256_register to ix86_check_avx_upper_register.
	(ix86_check_avx256_stores): Changed to ...
	(ix86_check_avx_upper_stores): ... this. Changed
	ix86_check_avx256_register to ix86_check_avx_upper_register.
	(ix86_avx_u128_mode_after): Changed
	avx_reg256_found to avx_upper_reg_found. Changed
	ix86_check_avx256_stores to ix86_check_avx_upper_stores.
	(ix86_avx_u128_mode_entry): Changed
	ix86_check_avx256_register to ix86_check_avx_upper_register.
	(ix86_avx_u128_mode_exit): Ditto.
	* config/i386/i386.h: (host_detect_local_cpu): New define.

2017-11-15  Sebastian Peryt  <sebastian.peryt@intel.com>

gcc/testsuite/

	PR target/82941
	PR target/82942
	* gcc.target/i386/pr82941-1.c: New test.
	* gcc.target/i386/pr82941-2.c: New test.
	* gcc.target/i386/pr82942-1.c: New test.
	* gcc.target/i386/pr82942-2.c: New test.

From-SVN: r254763