[llvm] [DLCov][NFC] Annotate intentionally-blank DebugLocs in existing code (PR #136192)

[Orlando Cazalet-Hyams via llvm-commits]

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@@ -2249,7 +2249,7 @@ bool llvm::promoteLoopAccessesToScalars(
     if (SawUnorderedAtomic)
       PreheaderLoad->setOrdering(AtomicOrdering::Unordered);
     PreheaderLoad->setAlignment(Alignment);
-    PreheaderLoad->setDebugLoc(DebugLoc());
+    PreheaderLoad->dropLocation();
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OCHyams wrote:

Why the change to `dropLocation`?

https://github.com/llvm/llvm-project/pull/136192