In LLVM FMA3 operands are dst, src1, src2, src3, however dst is not encoded as...

In LLVM FMA3 operands are dst, src1, src2, src3, however dst is not encoded as it is always src1. This was causing the encoding of the operands to be off by one.

Patch by Chris Bieneman.

llvm-svn: 188866