[X86] Don't use fsin/fcos/fsincos instructions ever

Summary:
Previously we would use these instructions if sse was disabled and fastmath was enabled.

As mentioned in D28335, this is a bad idea.

Reviewers: efriedma, scanon, DavidKreitzer

Reviewed By: DavidKreitzer

Subscribers: zvi, llvm-commits

Differential Revision: https://reviews.llvm.org/D36344

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@310762 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed