[llvm] [AMDGPU] Treat GEP offsets as signed in AMDGPUPromoteAlloca (PR #157682)

[Fabian Ritter via llvm-commits]

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@@ -465,7 +468,7 @@ static Value *GEPToVectorIndex(GetElementPtrInst *GEP, AllocaInst *Alloca,
 
   if (!OffsetQuot.isOne()) {
     ConstantInt *ConstMul =
-        ConstantInt::get(OffsetType, OffsetQuot.getZExtValue());
+        ConstantInt::get(OffsetType, OffsetQuot.getSExtValue());
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ritter-x2a wrote:

See #157864

https://github.com/llvm/llvm-project/pull/157682