rs6000-c.c: Map ALTIVEC_BUILTIN_VEC_UNPACKH for float argument to VSX_BUILTIN_DOUBLEH...

rs6000-c.c: Map ALTIVEC_BUILTIN_VEC_UNPACKH for float argument to VSX_BUILTIN_DOUBLEH_V4SF.

gcc/ChangeLog:

2018-07-05  Carl Love  <cel@us.ibm.com>

	* config/rs6000/rs6000-c.c: Map ALTIVEC_BUILTIN_VEC_UNPACKH for
	float argument to VSX_BUILTIN_DOUBLEH_V4SF.
	Map ALTIVEC_BUILTIN_VEC_UNPACKL for float argument to
	VSX_BUILTIN_DOUBLEL_V4SF.

gcc/testsuite/ChangeLog:

2018-07-05  Carl Love  <cel@us.ibm.com>
	* gcc.target/altivec-1-runnable.c: New test file.
	* gcc.target/altivec-2-runnable.c: New test file.
	* gcc.target/vsx-7.c (main2): Change expected expected instruction
	for tests.

From-SVN: r262439