[llvm] [SDAG] Reverse the canonicalization of isInf/isNanOrInf (PR #81404)

[Yingwei Zheng via llvm-commits]

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@@ -3467,12 +3467,51 @@ void SelectionDAGBuilder::visitICmp(const User &I) {
   setValue(&I, DAG.getSetCC(getCurSDLoc(), DestVT, Op1, Op2, Opcode));
 }
 
+SDValue SelectionDAGBuilder::lowerIsFpClass(Value *ClassVal,
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dtcxzyw wrote:

I will post an alternative later.

https://github.com/llvm/llvm-project/pull/81404