[llvm] [SelectionDAG][AMDGPU] Preserve known bits for demoted sret pointers (PR #203468)

[Keshav Vinayak Jha via llvm-commits]

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@@ -2219,16 +2219,18 @@ void SelectionDAGBuilder::visitRet(const ReturnInst &I) {
     MVT PtrValueVT = TLI.getPointerTy(DL, DL.getAllocaAddrSpace());
     SDValue RetPtr =
         DAG.getCopyFromReg(Chain, getCurSDLoc(), DemoteReg, PtrValueVT);
+    Type *RetTy = I.getOperand(0)->getType();
+    Align BaseAlign = DL.getPrefTypeAlign(RetTy);
+    RetPtr = TLI.annotateStackObjectPointer(RetPtr, DAG, getCurSDLoc(),
+                                            DL.getABITypeAlign(RetTy));
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keshavvinayak01 wrote:

Done.

https://github.com/llvm/llvm-project/pull/203468