[x86/SLH] Extract the logic to trace predicate state through calls to
a helper function with a nice overview comment. NFC.

This is a preperatory refactoring to implementing another component of
mitigation here that was descibed in the design document but hadn't been
implemented yet.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@338016 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed