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The transformation in LibCallSimplifier::replacePowWithSqrt with respect to -Inf uses a select instruction, which based on the observed behaviour, incorporates the side effects of the unchosen branch. This means that (for pow) a call to sqrt(-Inf) is materialized. Such a call is specified as having a domain error (C17 subclause 7.12....

...ownNeverInfinity()" returns true. > If there are other errno divergences for edge case values, we may need to > check other conditions. > > On Sat, Sep 12, 2020 at 9:37 PM Hubert Tong via llvm-dev < > llvm-dev at lists.llvm.org> wrote: > >> The transformation in LibCallSimplifier::replacePowWithSqrt with respect >> to -Inf uses a select instruction, which based on the observed behaviour, >> incorporates the side effects of the unchosen branch. This means that (for >> pow) a call to sqrt(-Inf) is materialized. Such a call is specified as >> having...

Sorry - I misread your example and the problem. I see now where LibCallSimplifier creates the select...but we are immediately erasing that select with the code from the godbolt example. Does the real motivating case have no uses of the pow() result value? On Mon, Sep 14, 2020 at 1:03 PM Sanjay Patel <spatel at rotateright.com> wrote: > Yes, I mean just bail out on...