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

[Orlando Cazalet-Hyams via llvm-commits]

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@@ -8095,10 +8123,14 @@ static bool optimizeBranch(BranchInst *Branch, const TargetLowering &TLI,
 }
 
 bool CodeGenPrepare::optimizeInst(Instruction *I, ModifyDT &ModifiedDT) {
+  bool AnyChange = false;
+  for (DPValue &DPV : I->getDbgValueRange())
+    AnyChange |= fixupDPValue(DPV);
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OCHyams wrote:

I suppose we want fixupDPValues to affect the return value "has a made change" to maintain parity with dbg.values. But is that desirable behaviour overall? Is this something we want to come back and change in the future? If so, wdyt of adding add a FIXME comment.

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