[llvm] [AMDGPU] Update base addr of dyn alloca considering GrowingUp stack (PR #119822)

[Matt Arsenault via llvm-commits]

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@@ -4023,10 +4024,20 @@ SDValue SITargetLowering::lowerDYNAMIC_STACKALLOCImpl(SDValue Op,
   Chain = DAG.getCALLSEQ_START(Chain, 0, 0, dl);
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arsenm wrote:

those are more for the benefit of MI code after the DAG than the chain dependency 

https://github.com/llvm/llvm-project/pull/119822