[llvm] [DirectX] Fix the writing of ConstantExpr GEPs to DXIL bitcode (PR #154446)

[Deric C. via llvm-commits]

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@@ -143,6 +143,10 @@ static bool fixI8UseChain(Instruction &I,
     LoadInst *NewLoad = Builder.CreateLoad(ElementType, NewGEP);
     ReplacedValues[Load] = NewLoad;
     Load->replaceAllUsesWith(NewLoad);
+    Load->setOperand(Load->getPointerOperandIndex(),
+                     PoisonValue::get(CE->getType()));
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Icohedron wrote:

Resolved by not manually removing the CE and instead letting a later call to `removeDeadConstantUsers` on a global remove it automatically.

https://github.com/llvm/llvm-project/pull/154446