[llvm] [DAGCombiner] Allow freeze to sink through fmul by adding it to AllowMultipleMaybePoisonOperands (PR #142250)

[Nikita Popov via llvm-commits]

https://github.com/nikic approved this pull request.

LGTM

The flag preservation matches the middle-end behavior (https://llvm.godbolt.org/z/a97Yr1Eh5). This assumes that rewrite-based FMF is transparent to freeze.

https://github.com/llvm/llvm-project/pull/142250