[llvm] [NVPTX] Change the alloca address space in NVPTXLowerAlloca (PR #154814)

[Alex MacLean via llvm-commits]

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@@ -1803,10 +1803,7 @@ SDValue NVPTXTargetLowering::LowerDYNAMIC_STACKALLOC(SDValue Op,
                   {Chain, DAG.getZExtOrTrunc(Size, DL, LocalVT),
                    DAG.getTargetConstant(Align, DL, MVT::i32)});
 
-  SDValue ASC = DAG.getAddrSpaceCast(
-      DL, Op.getValueType(), Alloc, ADDRESS_SPACE_LOCAL, ADDRESS_SPACE_GENERIC);
-
-  return DAG.getMergeValues({ASC, SDValue(Alloc.getNode(), 1)}, DL);
+  return Alloc;
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AlexMaclean wrote:

If we're removing this cast we should go ahead and remove this entire function as well as the `NVPTXISD::DYNAMIC_STACKALLOC` node. 

https://github.com/llvm/llvm-project/pull/154814