s390: Refactor block operation setmem

Vectorize memset with a constant length of less than or equal to 64
bytes.

Do not perform a libc function call into memset in case the size is not
a compile-time constant but bounded and the upper bound is less than or
equal to 256 bytes.

gcc/ChangeLog:

	* config/s390/s390-protos.h (s390_expand_setmem): Change
	function signature.
	* config/s390/s390.cc (s390_expand_setmem): For memset's less
	than or equal to 256 byte do not perform a libc call.
	* config/s390/s390.md: Change expander into a version which
	takes 8 operands.

gcc/testsuite/ChangeLog:

	* gcc.target/s390/memset-1.c: Test case memset1 makes use of
	vst, now.

0 files changed, 0 insertions, 0 deletions