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

[Noah Goldstein via Phabricator via llvm-commits]

goldstein.w.n accepted this revision.
goldstein.w.n added a comment.
This revision is now accepted and ready to land.

LGTM.



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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.
----------------
arsenm wrote:
> 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
Err yeah :/


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https://reviews.llvm.org/D156579