rs6000.c (rs6000_gimple_fold_builtin): Add support for folding of vector compares.

rs6000.c (rs6000_gimple_fold_builtin): Add support for folding of vector compares.

2017-11-15  Will Schmidt  <will_schmidt@vnet.ibm.com>

[gcc]

	* config/rs6000/rs6000.c (rs6000_gimple_fold_builtin): Add support for
	folding of vector compares.
	(fold_build_vec_cmp): New helper function.
	(fold_compare_helper): New helper function.
	(builtin_function_type): Add compare builtins to the list of functions
	having unsigned arguments.  Cosmetic updates to comment indentation.
	* config/rs6000/vsx.md (vcmpneb, vcmpneh, vcmpnew): Update to specify
	the not+eq combination.

[testsuite]

	* gcc.target/powerpc/builtins-3-p9.c: Add -O1, update
	expected codegen checks.
	* gcc.target/powerpc/vec-cmp-sel.c: Mark vars as volatile.
	* gcc.target/powerpc/vsu/vec-cmpne-0.c: Add -O1.
	* gcc.target/powerpc/vsu/vec-cmpne-1.c: Add -O1.
	* gcc.target/powerpc/vsu/vec-cmpne-2.c: Add -O1.
	* gcc.target/powerpc/vsu/vec-cmpne-3.c: Add -O1.
	* gcc.target/powerpc/vsu/vec-cmpne-4.c: Add -O1.
	* gcc.target/powerpc/vsu/vec-cmpne-5.c: Add -O1.
	* gcc.target/powerpc/vsu/vec-cmpne-6.c: Add -O1.

From-SVN: r254782