class SimplifyCFGOpt {
const TargetTransformInfo &TTI;
const DataLayout &DL;
- AssumptionCache *AC;
SmallPtrSetImpl<BasicBlock *> *LoopHeaders;
const SimplifyCFGOptions &Options;
public:
SimplifyCFGOpt(const TargetTransformInfo &TTI, const DataLayout &DL,
- AssumptionCache *AC,
SmallPtrSetImpl<BasicBlock *> *LoopHeaders,
const SimplifyCFGOptions &Opts)
- : TTI(TTI), DL(DL), AC(AC), LoopHeaders(LoopHeaders), Options(Opts) {}
+ : TTI(TTI), DL(DL), LoopHeaders(LoopHeaders), Options(Opts) {}
bool run(BasicBlock *BB);
};
///
/// We prefer to split the edge to 'end' so that there is a true/false entry to
/// the PHI, merging the third icmp into the switch.
-static bool TryToSimplifyUncondBranchWithICmpInIt(
+static bool tryToSimplifyUncondBranchWithICmpInIt(
ICmpInst *ICI, IRBuilder<> &Builder, const DataLayout &DL,
- const TargetTransformInfo &TTI, AssumptionCache *AC,
- const SimplifyCFGOptions &Options) {
+ const TargetTransformInfo &TTI, const SimplifyCFGOptions &Options) {
BasicBlock *BB = ICI->getParent();
// If the block has any PHIs in it or the icmp has multiple uses, it is too
ICI->eraseFromParent();
}
// BB is now empty, so it is likely to simplify away.
- return SimplifyCFG(BB, TTI, AC, Options) | true;
+ return simplifyCFG(BB, TTI, Options) | true;
}
// Ok, the block is reachable from the default dest. If the constant we're
ICI->replaceAllUsesWith(V);
ICI->eraseFromParent();
// BB is now empty, so it is likely to simplify away.
- return SimplifyCFG(BB, TTI, AC, Options) | true;
+ return simplifyCFG(BB, TTI, Options) | true;
}
// The use of the icmp has to be in the 'end' block, by the only PHI node in
/// Compute masked bits for the condition of a switch
/// and use it to remove dead cases.
-static bool EliminateDeadSwitchCases(SwitchInst *SI, AssumptionCache *AC,
+static bool eliminateDeadSwitchCases(SwitchInst *SI, AssumptionCache *AC,
const DataLayout &DL) {
Value *Cond = SI->getCondition();
unsigned Bits = Cond->getType()->getIntegerBitWidth();
/// If the switch is only used to initialize one or more
/// phi nodes in a common successor block with only two different
/// constant values, replace the switch with select.
-static bool SwitchToSelect(SwitchInst *SI, IRBuilder<> &Builder,
- AssumptionCache *AC, const DataLayout &DL,
+static bool switchToSelect(SwitchInst *SI, IRBuilder<> &Builder,
+ const DataLayout &DL,
const TargetTransformInfo &TTI) {
Value *const Cond = SI->getCondition();
PHINode *PHI = nullptr;
// see if that predecessor totally determines the outcome of this switch.
if (BasicBlock *OnlyPred = BB->getSinglePredecessor())
if (SimplifyEqualityComparisonWithOnlyPredecessor(SI, OnlyPred, Builder))
- return SimplifyCFG(BB, TTI, AC, Options) | true;
+ return simplifyCFG(BB, TTI, Options) | true;
Value *Cond = SI->getCondition();
if (SelectInst *Select = dyn_cast<SelectInst>(Cond))
if (SimplifySwitchOnSelect(SI, Select))
- return SimplifyCFG(BB, TTI, AC, Options) | true;
+ return simplifyCFG(BB, TTI, Options) | true;
// If the block only contains the switch, see if we can fold the block
// away into any preds.
++BBI;
if (SI == &*BBI)
if (FoldValueComparisonIntoPredecessors(SI, Builder))
- return SimplifyCFG(BB, TTI, AC, Options) | true;
+ return simplifyCFG(BB, TTI, Options) | true;
}
// Try to transform the switch into an icmp and a branch.
if (TurnSwitchRangeIntoICmp(SI, Builder))
- return SimplifyCFG(BB, TTI, AC, Options) | true;
+ return simplifyCFG(BB, TTI, Options) | true;
// Remove unreachable cases.
- if (EliminateDeadSwitchCases(SI, AC, DL))
- return SimplifyCFG(BB, TTI, AC, Options) | true;
+ if (eliminateDeadSwitchCases(SI, Options.AC, DL))
+ return simplifyCFG(BB, TTI, Options) | true;
- if (SwitchToSelect(SI, Builder, AC, DL, TTI))
- return SimplifyCFG(BB, TTI, AC, Options) | true;
+ if (switchToSelect(SI, Builder, DL, TTI))
+ return simplifyCFG(BB, TTI, Options) | true;
if (ForwardSwitchConditionToPHI(SI))
- return SimplifyCFG(BB, TTI, AC, Options) | true;
+ return simplifyCFG(BB, TTI, Options) | true;
// The conversion from switch to lookup tables results in difficult-to-analyze
// code and makes pruning branches much harder. This is a problem if the
// optimisation pipeline.
if (Options.ConvertSwitchToLookupTable &&
SwitchToLookupTable(SI, Builder, DL, TTI))
- return SimplifyCFG(BB, TTI, AC, Options) | true;
+ return simplifyCFG(BB, TTI, Options) | true;
if (ReduceSwitchRange(SI, Builder, DL, TTI))
- return SimplifyCFG(BB, TTI, AC, Options) | true;
+ return simplifyCFG(BB, TTI, Options) | true;
return false;
}
if (SelectInst *SI = dyn_cast<SelectInst>(IBI->getAddress())) {
if (SimplifyIndirectBrOnSelect(IBI, SI))
- return SimplifyCFG(BB, TTI, AC, Options) | true;
+ return simplifyCFG(BB, TTI, Options) | true;
}
return Changed;
}
for (++I; isa<DbgInfoIntrinsic>(I); ++I)
;
if (I->isTerminator() &&
- TryToSimplifyUncondBranchWithICmpInIt(ICI, Builder, DL, TTI, AC,
- Options))
+ tryToSimplifyUncondBranchWithICmpInIt(ICI, Builder, DL, TTI, Options))
return true;
}
// predecessor and use logical operations to update the incoming value
// for PHI nodes in common successor.
if (FoldBranchToCommonDest(BI, Options.BonusInstThreshold))
- return SimplifyCFG(BB, TTI, AC, Options) | true;
+ return simplifyCFG(BB, TTI, Options) | true;
return false;
}
// switch.
if (BasicBlock *OnlyPred = BB->getSinglePredecessor())
if (SimplifyEqualityComparisonWithOnlyPredecessor(BI, OnlyPred, Builder))
- return SimplifyCFG(BB, TTI, AC, Options) | true;
+ return simplifyCFG(BB, TTI, Options) | true;
// This block must be empty, except for the setcond inst, if it exists.
// Ignore dbg intrinsics.
++I;
if (&*I == BI) {
if (FoldValueComparisonIntoPredecessors(BI, Builder))
- return SimplifyCFG(BB, TTI, AC, Options) | true;
+ return simplifyCFG(BB, TTI, Options) | true;
} else if (&*I == cast<Instruction>(BI->getCondition())) {
++I;
// Ignore dbg intrinsics.
while (isa<DbgInfoIntrinsic>(I))
++I;
if (&*I == BI && FoldValueComparisonIntoPredecessors(BI, Builder))
- return SimplifyCFG(BB, TTI, AC, Options) | true;
+ return simplifyCFG(BB, TTI, Options) | true;
}
}
: ConstantInt::getFalse(BB->getContext());
BI->setCondition(CI);
RecursivelyDeleteTriviallyDeadInstructions(OldCond);
- return SimplifyCFG(BB, TTI, AC, Options) | true;
+ return simplifyCFG(BB, TTI, Options) | true;
}
}
}
// branches to us and one of our successors, fold the comparison into the
// predecessor and use logical operations to pick the right destination.
if (FoldBranchToCommonDest(BI, Options.BonusInstThreshold))
- return SimplifyCFG(BB, TTI, AC, Options) | true;
+ return simplifyCFG(BB, TTI, Options) | true;
// We have a conditional branch to two blocks that are only reachable
// from BI. We know that the condbr dominates the two blocks, so see if
if (BI->getSuccessor(0)->getSinglePredecessor()) {
if (BI->getSuccessor(1)->getSinglePredecessor()) {
if (HoistThenElseCodeToIf(BI, TTI))
- return SimplifyCFG(BB, TTI, AC, Options) | true;
+ return simplifyCFG(BB, TTI, Options) | true;
} else {
// If Successor #1 has multiple preds, we may be able to conditionally
// execute Successor #0 if it branches to Successor #1.
if (Succ0TI->getNumSuccessors() == 1 &&
Succ0TI->getSuccessor(0) == BI->getSuccessor(1))
if (SpeculativelyExecuteBB(BI, BI->getSuccessor(0), TTI))
- return SimplifyCFG(BB, TTI, AC, Options) | true;
+ return simplifyCFG(BB, TTI, Options) | true;
}
} else if (BI->getSuccessor(1)->getSinglePredecessor()) {
// If Successor #0 has multiple preds, we may be able to conditionally
if (Succ1TI->getNumSuccessors() == 1 &&
Succ1TI->getSuccessor(0) == BI->getSuccessor(0))
if (SpeculativelyExecuteBB(BI, BI->getSuccessor(1), TTI))
- return SimplifyCFG(BB, TTI, AC, Options) | true;
+ return simplifyCFG(BB, TTI, Options) | true;
}
// If this is a branch on a phi node in the current block, thread control
// through this block if any PHI node entries are constants.
if (PHINode *PN = dyn_cast<PHINode>(BI->getCondition()))
if (PN->getParent() == BI->getParent())
- if (FoldCondBranchOnPHI(BI, DL, AC))
- return SimplifyCFG(BB, TTI, AC, Options) | true;
+ if (FoldCondBranchOnPHI(BI, DL, Options.AC))
+ return simplifyCFG(BB, TTI, Options) | true;
// Scan predecessor blocks for conditional branches.
for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI)
if (BranchInst *PBI = dyn_cast<BranchInst>((*PI)->getTerminator()))
if (PBI != BI && PBI->isConditional())
if (SimplifyCondBranchToCondBranch(PBI, BI, DL))
- return SimplifyCFG(BB, TTI, AC, Options) | true;
+ return simplifyCFG(BB, TTI, Options) | true;
// Look for diamond patterns.
if (MergeCondStores)
if (BranchInst *PBI = dyn_cast<BranchInst>(PrevBB->getTerminator()))
if (PBI != BI && PBI->isConditional())
if (mergeConditionalStores(PBI, BI, DL))
- return SimplifyCFG(BB, TTI, AC, Options) | true;
+ return simplifyCFG(BB, TTI, Options) | true;
return false;
}
return Changed;
}
-bool llvm::SimplifyCFG(BasicBlock *BB, const TargetTransformInfo &TTI,
- AssumptionCache *AC, const SimplifyCFGOptions &Options,
+bool llvm::simplifyCFG(BasicBlock *BB, const TargetTransformInfo &TTI,
+ const SimplifyCFGOptions &Options,
SmallPtrSetImpl<BasicBlock *> *LoopHeaders) {
- return SimplifyCFGOpt(TTI, BB->getModule()->getDataLayout(), AC, LoopHeaders,
+ return SimplifyCFGOpt(TTI, BB->getModule()->getDataLayout(), LoopHeaders,
Options)
.run(BB);
}