[llvm] [AMDGPU] Update PromoteAlloca to handle GEPs with variable offset. (PR #122342)

[Matt Arsenault via llvm-commits]

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@@ -385,13 +385,42 @@ static bool isSupportedMemset(MemSetInst *I, AllocaInst *AI,
          match(I->getOperand(2), m_SpecificInt(Size)) && !I->isVolatile();
 }
 
+static bool hasVariableOffset(GetElementPtrInst *GEP) {
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arsenm wrote:

You can easily check if the operation is dead. This pass is essentially doing the same thing as SROA, which checks isInstructionTriviallyDead 

https://github.com/llvm/llvm-project/pull/122342