[llvm] [InstCombine]PtrReplacer: Correctly handle select with unavailable operands (PR #148829)

[Anshil Gandhi via llvm-commits]

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@@ -309,21 +318,26 @@ bool PointerReplacer::collectUsers() {
       // incoming values.
       Worklist.emplace_back(PHI);
       for (unsigned Idx = 0; Idx < PHI->getNumIncomingValues(); ++Idx) {
-        auto *IncomingValue = cast<Instruction>(PHI->getIncomingValue(Idx));
-        if (UsersToReplace.contains(IncomingValue))
-          continue;
-        if (!ValuesToRevisit.insert(IncomingValue))
+        if (!TryPushInstOperand(cast<Instruction>(PHI->getIncomingValue(Idx))))
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gandhi56 wrote:

This is a NFC and is already being tested in AMDGPU/ptr-replace-alloca.ll

https://github.com/llvm/llvm-project/pull/148829