bool expandAtomicLoadToCmpXchg(LoadInst *LI);
bool expandAtomicStore(StoreInst *SI);
bool tryExpandAtomicRMW(AtomicRMWInst *AI);
- bool expandAtomicRMWToLLSC(AtomicRMWInst *AI);
+ bool expandAtomicOpToLLSC(
+ Instruction *I, Value *Addr, AtomicOrdering MemOpOrder,
+ std::function<Value *(IRBuilder<> &, Value *)> PerformOp);
bool expandAtomicCmpXchg(AtomicCmpXchgInst *CI);
bool isIdempotentRMW(AtomicRMWInst *AI);
bool simplifyIdempotentRMW(AtomicRMWInst *AI);
switch (TLI->shouldExpandAtomicLoadInIR(LI)) {
case TargetLoweringBase::AtomicExpansionKind::None:
return false;
- case TargetLoweringBase::AtomicExpansionKind::LLSC: {
+ case TargetLoweringBase::AtomicExpansionKind::LLSC:
+ return expandAtomicOpToLLSC(
+ LI, LI->getPointerOperand(), LI->getOrdering(),
+ [](IRBuilder<> &Builder, Value *Loaded) { return Loaded; });
+ case TargetLoweringBase::AtomicExpansionKind::LLOnly:
return expandAtomicLoadToLL(LI);
- }
- case TargetLoweringBase::AtomicExpansionKind::CmpXChg: {
+ case TargetLoweringBase::AtomicExpansionKind::CmpXChg:
return expandAtomicLoadToCmpXchg(LI);
}
- }
llvm_unreachable("Unhandled case in tryExpandAtomicLoad");
}
// to be single-copy atomic by ARM is an ldrexd (A3.5.3).
Value *Val =
TLI->emitLoadLinked(Builder, LI->getPointerOperand(), LI->getOrdering());
+ TLI->emitAtomicCmpXchgNoStoreLLBalance(Builder);
LI->replaceAllUsesWith(Val);
LI->eraseFromParent();
NewLoaded = Builder.CreateExtractValue(Pair, 0, "newloaded");
}
-bool AtomicExpand::tryExpandAtomicRMW(AtomicRMWInst *AI) {
- switch (TLI->shouldExpandAtomicRMWInIR(AI)) {
- case TargetLoweringBase::AtomicExpansionKind::None:
- return false;
- case TargetLoweringBase::AtomicExpansionKind::LLSC: {
- return expandAtomicRMWToLLSC(AI);
- }
- case TargetLoweringBase::AtomicExpansionKind::CmpXChg: {
- return expandAtomicRMWToCmpXchg(AI, createCmpXchgInstFun);
- }
- }
- llvm_unreachable("Unhandled case in tryExpandAtomicRMW");
-}
-
/// Emit IR to implement the given atomicrmw operation on values in registers,
/// returning the new value.
static Value *performAtomicOp(AtomicRMWInst::BinOp Op, IRBuilder<> &Builder,
}
}
-bool AtomicExpand::expandAtomicRMWToLLSC(AtomicRMWInst *AI) {
- AtomicOrdering MemOpOrder = AI->getOrdering();
- Value *Addr = AI->getPointerOperand();
- BasicBlock *BB = AI->getParent();
+bool AtomicExpand::tryExpandAtomicRMW(AtomicRMWInst *AI) {
+ switch (TLI->shouldExpandAtomicRMWInIR(AI)) {
+ case TargetLoweringBase::AtomicExpansionKind::None:
+ return false;
+ case TargetLoweringBase::AtomicExpansionKind::LLSC:
+ return expandAtomicOpToLLSC(AI, AI->getPointerOperand(), AI->getOrdering(),
+ [&](IRBuilder<> &Builder, Value *Loaded) {
+ return performAtomicOp(AI->getOperation(),
+ Builder, Loaded,
+ AI->getValOperand());
+ });
+ case TargetLoweringBase::AtomicExpansionKind::CmpXChg:
+ return expandAtomicRMWToCmpXchg(AI, createCmpXchgInstFun);
+ default:
+ llvm_unreachable("Unhandled case in tryExpandAtomicRMW");
+ }
+}
+
+bool AtomicExpand::expandAtomicOpToLLSC(
+ Instruction *I, Value *Addr, AtomicOrdering MemOpOrder,
+ std::function<Value *(IRBuilder<> &, Value *)> PerformOp) {
+ BasicBlock *BB = I->getParent();
Function *F = BB->getParent();
LLVMContext &Ctx = F->getContext();
// atomicrmw.end:
// fence?
// [...]
- BasicBlock *ExitBB = BB->splitBasicBlock(AI->getIterator(), "atomicrmw.end");
+ BasicBlock *ExitBB = BB->splitBasicBlock(I->getIterator(), "atomicrmw.end");
BasicBlock *LoopBB = BasicBlock::Create(Ctx, "atomicrmw.start", F, ExitBB);
- // This grabs the DebugLoc from AI.
- IRBuilder<> Builder(AI);
+ // This grabs the DebugLoc from I.
+ IRBuilder<> Builder(I);
// The split call above "helpfully" added a branch at the end of BB (to the
// wrong place), but we might want a fence too. It's easiest to just remove
Builder.SetInsertPoint(LoopBB);
Value *Loaded = TLI->emitLoadLinked(Builder, Addr, MemOpOrder);
- Value *NewVal =
- performAtomicOp(AI->getOperation(), Builder, Loaded, AI->getValOperand());
+ Value *NewVal = PerformOp(Builder, Loaded);
Value *StoreSuccess =
TLI->emitStoreConditional(Builder, NewVal, Addr, MemOpOrder);
Builder.SetInsertPoint(ExitBB, ExitBB->begin());
- AI->replaceAllUsesWith(Loaded);
- AI->eraseFromParent();
+ I->replaceAllUsesWith(Loaded);
+ I->eraseFromParent();
return true;
}