[llvm] [InstCombine] Remove dead phi web (PR #108876)

[Yingwei Zheng via llvm-commits]

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@@ -53,6 +53,34 @@ void InstCombinerImpl::PHIArgMergedDebugLoc(Instruction *Inst, PHINode &PN) {
   }
 }
 
+// If the phi is within a phi web, which is formed by the def-use chain
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dtcxzyw wrote:

```suggestion
/// If the phi is within a phi web, which is formed by the def-use chain
```

https://github.com/llvm/llvm-project/pull/108876