[x86] Clean up and enhance a test around eflags copying.

This adds the basic test cases from all the EFLAGS bugs in more direct
forms. It also switches to generated check lines, and includes both
32-bit and 64-bit variations.

No functionality changing here, just setting things up to have a nice
clean asm diff in my EFLAGS patch.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@329056 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed