Pull in r163967 from upstream llvm trunk:
Pull in r163967 from upstream llvm trunk:

  X86: Emitting x87 fsin/fcos for sinf/cosf is not safe without unsafe
  fp math.

This should make clang emit calls to libm for sinf/cosf by default.

MFC after:	1 week

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase