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-rw-r--r--lib/Transforms/Utils/SimplifyCFG.cpp42
1 files changed, 20 insertions, 22 deletions
diff --git a/lib/Transforms/Utils/SimplifyCFG.cpp b/lib/Transforms/Utils/SimplifyCFG.cpp
index 870e2b2ade..427ac4ed14 100644
--- a/lib/Transforms/Utils/SimplifyCFG.cpp
+++ b/lib/Transforms/Utils/SimplifyCFG.cpp
@@ -3583,32 +3583,30 @@ static bool SwitchToLookupTable(SwitchInst *SI,
}
bool SimplifyCFGOpt::SimplifySwitch(SwitchInst *SI, IRBuilder<> &Builder) {
- // If this switch is too complex to want to look at, ignore it.
- if (!isValueEqualityComparison(SI))
- return false;
-
BasicBlock *BB = SI->getParent();
- // If we only have one predecessor, and if it is a branch on this value,
- // see if that predecessor totally determines the outcome of this switch.
- if (BasicBlock *OnlyPred = BB->getSinglePredecessor())
- if (SimplifyEqualityComparisonWithOnlyPredecessor(SI, OnlyPred, Builder))
- return SimplifyCFG(BB) | true;
+ if (isValueEqualityComparison(SI)) {
+ // If we only have one predecessor, and if it is a branch on this value,
+ // see if that predecessor totally determines the outcome of this switch.
+ if (BasicBlock *OnlyPred = BB->getSinglePredecessor())
+ if (SimplifyEqualityComparisonWithOnlyPredecessor(SI, OnlyPred, Builder))
+ return SimplifyCFG(BB) | true;
- Value *Cond = SI->getCondition();
- if (SelectInst *Select = dyn_cast<SelectInst>(Cond))
- if (SimplifySwitchOnSelect(SI, Select))
- return SimplifyCFG(BB) | true;
+ Value *Cond = SI->getCondition();
+ if (SelectInst *Select = dyn_cast<SelectInst>(Cond))
+ if (SimplifySwitchOnSelect(SI, Select))
+ return SimplifyCFG(BB) | true;
- // If the block only contains the switch, see if we can fold the block
- // away into any preds.
- BasicBlock::iterator BBI = BB->begin();
- // Ignore dbg intrinsics.
- while (isa<DbgInfoIntrinsic>(BBI))
- ++BBI;
- if (SI == &*BBI)
- if (FoldValueComparisonIntoPredecessors(SI, Builder))
- return SimplifyCFG(BB) | true;
+ // If the block only contains the switch, see if we can fold the block
+ // away into any preds.
+ BasicBlock::iterator BBI = BB->begin();
+ // Ignore dbg intrinsics.
+ while (isa<DbgInfoIntrinsic>(BBI))
+ ++BBI;
+ if (SI == &*BBI)
+ if (FoldValueComparisonIntoPredecessors(SI, Builder))
+ return SimplifyCFG(BB) | true;
+ }
// Try to transform the switch into an icmp and a branch.
if (TurnSwitchRangeIntoICmp(SI, Builder))