[PATCH] D86403: [DAGCombine]: Fold X/Sqrt(X) to Sqrt(X).

[Sanjay Patel via Phabricator via llvm-commits]

spatel added inline comments.


================
Comment at: llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp:13358
+  if ((Options.NoNaNsFPMath || Flags.hasNoNaNs()) &&
+      (Options.UnsafeFPMath || Flags.hasAllowReassociation()))
+    if (N1.getOpcode() == ISD::FSQRT && N0 == N1.getOperand(0)) {
----------------
Also, 'reassoc' generally means anything can happen, but if we want to be safer, we could require 'nsz' because this transform would change the result for a -0.0 input.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D86403/new/

https://reviews.llvm.org/D86403