[llvm] [WIP][SPARC] Allow overaligned `alloca`s (PR #107223)

[Sergei Barannikov via llvm-commits]

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@@ -2764,20 +2764,27 @@ static SDValue LowerDYNAMIC_STACKALLOC(SDValue Op, SelectionDAG &DAG,
                                        const SparcSubtarget *Subtarget) {
   SDValue Chain = Op.getOperand(0);  // Legalize the chain.
   SDValue Size  = Op.getOperand(1);  // Legalize the size.
-  MaybeAlign Alignment =
-      cast<ConstantSDNode>(Op.getOperand(2))->getMaybeAlignValue();
+  SDValue Alignment = Op.getOperand(2); // Legalize the alignment.
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s-barannikov wrote:

Drop the comments? The assignments don't legalize anything.

https://github.com/llvm/llvm-project/pull/107223