gcc/
	* internal-fn.def (SIGNBIT): New.
	* config/aarch64/aarch64-simd.md (signbitv2sf2): New expand
	defined.
	(signbitv4sf2): Likewise.

gcc/testsuite/
	* gcc.target/aarch64/signbitv4sf.c: New test.
	* gcc.target/aarch64/signbitv2sf.c: New test.

From-SVN: r271149