[llvm] [LV][NFC] Remove undef from phi incoming values (PR #163762)

[Florian Hahn via llvm-commits]

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@@ -39,7 +39,7 @@ define i32 @foo(i32 %n, ptr nocapture %A) {
   br i1 %11, label %3, label %._crit_edge
 
 ._crit_edge:                                      ; preds = %3, %0
-  %sum.0.lcssa = phi i32 [ undef, %0 ], [ %9, %3 ]
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fhahn wrote:

we could remove the phi node alltogether, by removing the unneeded check in the entry block

https://github.com/llvm/llvm-project/pull/163762