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[GVN][NFC] Use early return in phiTranslateImpl() #149268

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Merged
merged 1 commit into from
Jul 17, 2025
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[GVN][NFC] Use early return in phiTranslateImpl() #149268

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15 changes: 9 additions & 6 deletions llvm/lib/Transforms/Scalar/GVN.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -2367,12 +2367,15 @@ uint32_t GVNPass::ValueTable::phiTranslateImpl(const BasicBlock *Pred,
// See if we can refine the value number by looking at the PN incoming value
// for the given predecessor.
if (PHINode *PN = NumberingPhi[Num]) {
if (PN->getParent() == PhiBlock)
for (unsigned I = 0; I != PN->getNumIncomingValues(); ++I)
if (PN->getIncomingBlock(I) == Pred)
if (uint32_t TransVal = lookup(PN->getIncomingValue(I), false))
return TransVal;
return Num;
if (PN->getParent() != PhiBlock)
return Num;

for (unsigned I = 0; I != PN->getNumIncomingValues(); ++I) {
if (PN->getIncomingBlock(I) != Pred)
continue;
if (uint32_t TransVal = lookup(PN->getIncomingValue(I), false))
return TransVal;
}
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@fhahn fhahn Jul 17, 2025

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previously we would return Num; if no translated incoming value could be found, now we fall through.

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@madhur13490 madhur13490 Jul 17, 2025

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Yes, realized this. Reverted in #149270

}

if (BasicBlock *BB = NumberingBB[Num]) {
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