[llvm] [RemoveDIs][DebugInfo] Handle DPVAssigns in Assignment Tracking excluding lowering (PR #78982)

[Orlando Cazalet-Hyams via llvm-commits]

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@@ -1241,6 +1241,7 @@ void SelectionDAGBuilder::visitDbgInfo(const Instruction &I) {
                              It->Expr, Vals.size() > 1, It->DL, SDNodeOrder);
       }
     }
+    return;
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OCHyams wrote:

Please can you add a comment, either here or the top of the outer `if` that explains we don't need to look at DPValues when assignment tracking analysis has given us location info.

https://github.com/llvm/llvm-project/pull/78982