[StructurizeCFG] Remove one SSAUpdater::AddAvailableValue. NFCI.

[jayfoad]

No description provided.

[llvmbot]

@llvm/pr-subscribers-llvm-transforms

Author: Jay Foad (jayfoad)

Changes

---

Full diff: https://github.com/llvm/llvm-project/pull/115472.diff

1 Files Affected:

• (modified) llvm/lib/Transforms/Scalar/StructurizeCFG.cpp (-1)

diff --git a/llvm/lib/Transforms/Scalar/StructurizeCFG.cpp b/llvm/lib/Transforms/Scalar/StructurizeCFG.cpp
index 2a0f0423bbc8f6..6eb292e34fd93c 100644
--- a/llvm/lib/Transforms/Scalar/StructurizeCFG.cpp
+++ b/llvm/lib/Transforms/Scalar/StructurizeCFG.cpp
@@ -616,7 +616,6 @@ void StructurizeCFG::insertConditions(bool Loops) {
     BasicBlock *SuccFalse = Term->getSuccessor(1);
 
     PhiInserter.Initialize(Boolean, "");
-    PhiInserter.AddAvailableValue(&Func->getEntryBlock(), Default);
     PhiInserter.AddAvailableValue(Loops ? SuccFalse : Parent, Default);
 
     BBPredicates &Preds = Loops ? LoopPreds[SuccFalse] : Predicates[SuccTrue];

[jayfoad]

Found by experimentation. Does anyone know this code well enough to say for sure whether it is redundant? Or are we missing test coverage?

[arsenm]

I'm guessing this would only be needed if there were an unconditional branch from the entry block. But in that case, it would never be necessary to insert a phi there so this seems fine