[PATCH] D31164: [IR] Add AllowContract to FastMathFlags
Matt Arsenault via Phabricator via llvm-commits
llvm-commits at lists.llvm.org
Mon Mar 20 20:43:37 PDT 2017
arsenm added inline comments.
Comment at: docs/LangRef.rst:2197-2200
+ Allow floating-point contraction (e.g. fusing a multiply followed by an
+ addition into a fused multiply-and-add).
> arsenm wrote:
> > Should we also have an unsafe algebra that preserves signed zeros/nans etc?
> @arsenm : isn't it the default when there is no `nsz` or `nnan` ?
No, that is normal safe math. I mean unsafe algebraic transformations similar to contraction which will preserve nan/signed zeros/inf behavior but are still not safe.
More information about the llvm-commits