- FCMOV only supports a subset of X86 conditions. Skip boolean
simplification if X86 condition is not valid for FCMOV.
- add a minimal test case for PR13577.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161732 91177308-0d34-0410-b5e6-96231b3b80d8