[llvm] llvm-reduce: Fix operand reduction asserting on target ext types (PR #132732)

[Arthur Eubanks via llvm-commits]

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@@ -134,6 +134,15 @@ void llvm::reduceOperandsZeroDeltaPass(TestRunner &Test) {
     if (auto *IntTy = dyn_cast<IntegerType>(Op->getType()))
       if (switchCaseExists(Op, ConstantInt::get(IntTy, 0)))
         return nullptr;
+
+    if (auto *TET = dyn_cast<TargetExtType>(Op->getType())) {
+      if (isa<ConstantTargetNone, PoisonValue>(Op))
+        return nullptr;
+      if (TET->hasProperty(TargetExtType::HasZeroInit))
+        return ConstantTargetNone::get(TET);
+      return PoisonValue::get(TET);
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aeubanks wrote:

can we bail out here and have a separate pass that reduces operands to poison (if they're not already a constant)? lumping the poison into the reduce to zero pass seems weird

https://github.com/llvm/llvm-project/pull/132732