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

[Keshav Vinayak Jha via llvm-commits]

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@@ -19717,14 +19709,19 @@ void SITargetLowering::computeKnownBitsForTargetNode(const SDValue Op,
       Op, Known, DemandedElts, DAG, Depth);
 }
 
+void SITargetLowering::computeKnownBitsForSRetPointer(
+    KnownBits &Known, const MachineFunction &) const {
+  Known.Zero.setHighBits(getSubtarget()->getKnownHighZeroBitsForFrameIndex());
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keshavvinayak01 wrote:

Makes sense, `SITargetLowering::computeKnownBitsForFrameIndex`  now calls `computeKnownBitsForStackObjectPointer`.

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