s390: Revise vector reverse elements

Replace UNSPEC_VEC_ELTSWAP with a vec_select implementation.

Furthermore, for a vector reverse elements operation between registers
of mode V8HI perform three rotates instead of a vperm operation since
the latter involves loading the permutation vector from the literal
pool.

Prior z15, instead of
  larl + vl + vl + vperm
prefer
  vl + vpdi (+ verllg (+ verllf))
for a load operation.

Likewise, prior z15, instead of
  larl + vl + vperm + vst
prefer
  vpdi (+ verllg (+ verllf)) + vst
for a store operation.

gcc/ChangeLog:

	* config/s390/s390.md: Remove UNSPEC_VEC_ELTSWAP.
	* config/s390/vector.md (eltswapv16qi): New expander.
	(*eltswapv16qi): New insn and splitter.
	(eltswapv8hi): New insn and splitter.
	(eltswap<mode>): New insn and splitter for modes V_HW_4 as well
	as V_HW_2.
	* config/s390/vx-builtins.md (eltswap<mode>): Remove.
	(*eltswapv16qi): Remove.
	(*eltswap<mode>): Remove.
	(*eltswap<mode>_emu): Remove.

gcc/testsuite/ChangeLog:

	* gcc.target/s390/zvector/vec-reve-load-halfword-z14.c: Remove
	vperm and substitude by vpdi et al.
	* gcc.target/s390/zvector/vec-reve-load-halfword.c: Likewise.
	* gcc.target/s390/vector/reverse-elements-1.c: New test.
	* gcc.target/s390/vector/reverse-elements-2.c: New test.
	* gcc.target/s390/vector/reverse-elements-3.c: New test.
	* gcc.target/s390/vector/reverse-elements-4.c: New test.
	* gcc.target/s390/vector/reverse-elements-5.c: New test.
	* gcc.target/s390/vector/reverse-elements-6.c: New test.
	* gcc.target/s390/vector/reverse-elements-7.c: New test.

0 files changed, 0 insertions, 0 deletions