[llvm] [DLCov][NFC] Propagate annotated DebugLocs through transformations (PR #138047)

[Orlando Cazalet-Hyams via llvm-commits]

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@@ -112,12 +112,18 @@ class FMFSource {
 /// Common base class shared among various IRBuilders.
 class IRBuilderBase {
   /// Pairs of (metadata kind, MDNode *) that should be added to all newly
-  /// created instructions, like !dbg metadata.
+  /// created instructions, excluding !dbg metadata, which is stored in the
+  // StoredDL field.
   SmallVector<std::pair<unsigned, MDNode *>, 2> MetadataToCopy;
+  // The DebugLoc that will be applied to instructions inserted by this builder.
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OCHyams wrote:

nit `///`

https://github.com/llvm/llvm-project/pull/138047