[llvm] [InstCombine] If inst in unreachable refers to an inst change it to poison (#65107) (PR #78444)

[Nikita Popov via llvm-commits]

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@@ -3231,9 +3231,12 @@ void InstCombinerImpl::handleUnreachableFrom(
     MadeIRChange = true;
   }
 
-  // RemoveDIs: to match behaviour in dbg.value mode, drop debug-info on
-  // terminator too.
-  BB->getTerminator()->dropDbgValues();
+  SmallVector<Value *, 4> Changed;
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nikic wrote:

```suggestion
  SmallVector<Value *> Changed;
```

https://github.com/llvm/llvm-project/pull/78444