Hi all,

The aarch64_vmls<mode> pattern claims to perform a normal vector floating-point multiply-subtract but in fact
performs a fused multiply-subtract. This is fine when -ffp-contract=fast, but it's not guarded on anything so
will generate the FMLS instruction even when -ffp-contract=off.

The solution is just to delete the pattern. If -ffp-contract=fast then an fma operation will have been generated
and the fnma<mode>4 would be used to generate the FMLS instruction.

Bootstrapped and tested on aarch64-none-linux-gnu.

Ok for trunk and GCC 6 and 5? GCC 4.9 needs a different -mtune option in the testcase to trigger the testcase...

Thanks,
Kyrill

2016-05-17  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>

     PR target/70809
     * config/aarch64/aarch64-simd.md (aarch64_vmls<mode>): Delete.

2016-05-17  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>

     PR target/70809
     * gcc.target/aarch64/pr70809_1.c: New test.