[llvm] [DebugInfo][RemoveDIs] Support maintaining DPValues in CodeGenPrepare (PR #73660)

[Orlando Cazalet-Hyams via llvm-commits]

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@@ -2882,6 +2901,7 @@ class TypePromotionTransaction {
   };
 
   /// Set the operand of an instruction with a new value.
+  // XXX jmorse -- what about for dbg.values?
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OCHyams wrote:

Leftover dev comment?

https://github.com/llvm/llvm-project/pull/73660