[PATCH] D61802: [LoopVectorize] Enable float minmax reductions via instruction flag

[Nicolau Werneck via Phabricator via llvm-commits]

nlw0 added a comment.

My main motivation is just enabling vectorization for "minimum" loops without requiring function attributes. I think having a focus might help ensure I can contribute something, and a small patch would be nice too. I'll gladly work on a larger issue if it's within my reach, though, or if turns out to be required.

Where can I find more information about the expected behavior of fcmp? I don't understand why signed zeros should be relevant, the resulting behavior should just be whatever is caused by fcmp, either ignoring them or not. And ignoring should be the default anyway from what I recall from IEEE-754. Anyway, isn't this test here just about the fact NaNs violate associativity?

Why would select take a flag, isn't the whole semantics encoded in the boolean returned from fcmp?


Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D61802/new/

https://reviews.llvm.org/D61802