[llvm] [X86] ptest is commutable as long as only the Z flag is used. (PR #88969)

[Simon Pilgrim via llvm-commits]

https://github.com/RKSimon commented:

No objections from me - technically we're still missing the ability to fold some loads that appear later (from stack spills etc.) but short of making a full pseudo instruction I'm not sure whether we can do it cleanly.

https://github.com/llvm/llvm-project/pull/88969