[PATCH] D57434: Optimize pow(X, 0.75) to sqrt(X) * sqrt(sqrt(X))

[Evandro Menezes via Phabricator via llvm-commits]

evandro accepted this revision.
evandro added a comment.
This revision is now accepted and ready to land.

After the `nsz` check is addressed, it LGTM.



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Comment at: llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp:11852
     // pow(-inf, 0.25) = +inf; sqrt(sqrt(-inf)) =  NaN.
+    // pow(-0.0, 0.75) = +0.0; sqrt(-0.0) * sqrt(sqrt(-0.0)) = +0.0.
+    // pow(-inf, 0.75) = +inf; sqrt(-inf) * sqrt(sqrt(-inf)) =  NaN.
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lebedev.ri wrote:
> Looks like this doesn't //need// to be guarded by `nsz` flag?
This.


Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D57434/new/

https://reviews.llvm.org/D57434