[llvm] [InstCombine] Resolve TODO: nnan nsz X / -0.0 -> copysign(inf, X) (PR #79766)

[Matt Arsenault via llvm-commits]

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@@ -1600,7 +1600,18 @@ Instruction *InstCombinerImpl::foldFDivConstantDivisor(BinaryOperator &I) {
   // nnan X / +0.0 -> copysign(inf, X)
   if (I.hasNoNaNs() && match(I.getOperand(1), m_Zero())) {
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arsenm wrote:

Should this be m_PosZeroFP? 

https://github.com/llvm/llvm-project/pull/79766