[PATCH] D156579: InstCombine: Fold fneg (ldexp x, n) -> ldexp (fneg x), n

[Matt Arsenault via Phabricator via llvm-commits]

arsenm added inline comments.


================
Comment at: llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp:2573
+
+  if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(FNegOp)) {
+    // Make sure to preserve flags and metadata on the call.
----------------
goldstein.w.n wrote:
> Doesn't exponent need to by odd for this? I.e
> 
> -(X ^ 2) != ((-X) ^ 2).
It’s not a square, it’s X * 2^N


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D156579/new/

https://reviews.llvm.org/D156579