[llvm] [DebugInfo][RemoveDIs] Don't allocate one DPMarker per instruction (PR #79345)

[Orlando Cazalet-Hyams via llvm-commits]

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@@ -86,6 +86,11 @@ class Instruction : public User,
   /// Returns true if any DPValues are attached to this instruction.
   bool hasDbgValues() const;
 
+  /// Transfer any DPValues on the position \p It onto this instruction.
+  /// \returns true if adoption worked, false otherwise.
+  bool adoptDbgValues(BasicBlock *BB, InstListType::iterator It,
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OCHyams wrote:

Is there a way to word this where the method of moving is more explicitly called out (plus consequences of returning true/false, if it's easy to summarise)?

https://github.com/llvm/llvm-project/pull/79345