cl::location(LimitFloatPrecision),
cl::init(0));
+static cl::opt<bool>
+EnableFMFInDAG("enable-fmf-dag", cl::init(false), cl::Hidden,
+ cl::desc("Enable fast-math-flags for DAG nodes"));
+
// Limit the width of DAG chains. This is important in general to prevent
-// prevent DAG-based analysis from blowing up. For example, alias analysis and
+// DAG-based analysis from blowing up. For example, alias analysis and
// load clustering may not complete in reasonable time. It is difficult to
// recognize and avoid this situation within each individual analysis, and
// future analyses are likely to have the same behavior. Limiting DAG width is
-// the safe approach, and will be especially important with global DAGs.
+// the safe approach and will be especially important with global DAGs.
//
// MaxParallelChains default is arbitrarily high to avoid affecting
// optimization, but could be lowered to improve compile time. Any ld-ld-st-st
SDValue SelectionDAGBuilder::getNonRegisterValue(const Value *V) {
// If we already have an SDValue for this value, use it.
SDValue &N = NodeMap[V];
- if (N.getNode()) return N;
+ if (N.getNode()) {
+ if (isa<ConstantSDNode>(N) || isa<ConstantFPSDNode>(N)) {
+ // Remove the debug location from the node as the node is about to be used
+ // in a location which may differ from the original debug location. This
+ // is relevant to Constant and ConstantFP nodes because they can appear
+ // as constant expressions inside PHI nodes.
+ N->setDebugLoc(DebugLoc());
+ }
+ return N;
+ }
// Otherwise create a new SDValue and remember it.
SDValue Val = getValueImpl(V);
bool nuw = false;
bool nsw = false;
bool exact = false;
+ FastMathFlags FMF;
+
if (const OverflowingBinaryOperator *OFBinOp =
dyn_cast<const OverflowingBinaryOperator>(&I)) {
nuw = OFBinOp->hasNoUnsignedWrap();
if (const PossiblyExactOperator *ExactOp =
dyn_cast<const PossiblyExactOperator>(&I))
exact = ExactOp->isExact();
-
+ if (const FPMathOperator *FPOp = dyn_cast<const FPMathOperator>(&I))
+ FMF = FPOp->getFastMathFlags();
+
+ SDNodeFlags Flags;
+ Flags.setExact(exact);
+ Flags.setNoSignedWrap(nsw);
+ Flags.setNoUnsignedWrap(nuw);
+ if (EnableFMFInDAG) {
+ Flags.setAllowReciprocal(FMF.allowReciprocal());
+ Flags.setNoInfs(FMF.noInfs());
+ Flags.setNoNaNs(FMF.noNaNs());
+ Flags.setNoSignedZeros(FMF.noSignedZeros());
+ Flags.setUnsafeAlgebra(FMF.unsafeAlgebra());
+ }
SDValue BinNodeValue = DAG.getNode(OpCode, getCurSDLoc(), Op1.getValueType(),
- Op1, Op2, nuw, nsw, exact);
+ Op1, Op2, &Flags);
setValue(&I, BinNodeValue);
}
dyn_cast<const PossiblyExactOperator>(&I))
exact = ExactOp->isExact();
}
-
+ SDNodeFlags Flags;
+ Flags.setExact(exact);
+ Flags.setNoSignedWrap(nsw);
+ Flags.setNoUnsignedWrap(nuw);
SDValue Res = DAG.getNode(Opcode, getCurSDLoc(), Op1.getValueType(), Op1, Op2,
- nuw, nsw, exact);
+ &Flags);
setValue(&I, Res);
}
while (TLI.getTypeAction(Ctx, VT) == TargetLoweringBase::TypeSplitVector)
VT = TLI.getTypeToTransformTo(Ctx, VT);
- if (Opc != ISD::DELETED_NODE && TLI.isOperationLegalOrCustom(Opc, VT)) {
+ if (Opc != ISD::DELETED_NODE && TLI.isOperationLegalOrCustom(Opc, VT) &&
+ // If the underlying comparison instruction is used by any other instruction,
+ // the consumed instructions won't be destroyed, so it is not profitable
+ // to convert to a min/max.
+ cast<SelectInst>(&I)->getCondition()->hasOneUse()) {
OpCode = Opc;
LHSVal = getValue(LHS);
RHSVal = getValue(RHS);
bool isVolatile = I.isVolatile();
bool isNonTemporal = I.getMetadata(LLVMContext::MD_nontemporal) != nullptr;
- bool isInvariant = I.getMetadata(LLVMContext::MD_invariant_load) != nullptr;
+
+ // The IR notion of invariant_load only guarantees that all *non-faulting*
+ // invariant loads result in the same value. The MI notion of invariant load
+ // guarantees that the load can be legally moved to any location within its
+ // containing function. The MI notion of invariant_load is stronger than the
+ // IR notion of invariant_load -- an MI invariant_load is an IR invariant_load
+ // with a guarantee that the location being loaded from is dereferenceable
+ // throughout the function's lifetime.
+
+ bool isInvariant = I.getMetadata(LLVMContext::MD_invariant_load) != nullptr &&
+ isDereferenceablePointer(SV, *DAG.getTarget().getDataLayout());
unsigned Alignment = I.getAlignment();
AAMDNodes AAInfo;
// Serialize volatile loads with other side effects.
Root = getRoot();
else if (AA->pointsToConstantMemory(
- AliasAnalysis::Location(SV, AA->getTypeStoreSize(Ty), AAInfo))) {
+ MemoryLocation(SV, AA->getTypeStoreSize(Ty), AAInfo))) {
// Do not serialize (non-volatile) loads of constant memory with anything.
Root = DAG.getEntryNode();
ConstantMemory = true;
Root = TLI.prepareVolatileOrAtomicLoad(Root, dl, DAG);
SmallVector<SDValue, 4> Values(NumValues);
- SmallVector<SDValue, 4> Chains(std::min(unsigned(MaxParallelChains),
- NumValues));
+ SmallVector<SDValue, 4> Chains(std::min(MaxParallelChains, NumValues));
EVT PtrVT = Ptr.getValueType();
unsigned ChainI = 0;
for (unsigned i = 0; i != NumValues; ++i, ++ChainI) {
SDValue Ptr = getValue(PtrV);
SDValue Root = getRoot();
- SmallVector<SDValue, 4> Chains(std::min(unsigned(MaxParallelChains),
- NumValues));
+ SmallVector<SDValue, 4> Chains(std::min(MaxParallelChains, NumValues));
EVT PtrVT = Ptr.getValueType();
bool isVolatile = I.isVolatile();
bool isNonTemporal = I.getMetadata(LLVMContext::MD_nontemporal) != nullptr;
const MDNode *Ranges = I.getMetadata(LLVMContext::MD_range);
SDValue InChain = DAG.getRoot();
- if (AA->pointsToConstantMemory(
- AliasAnalysis::Location(PtrOperand,
- AA->getTypeStoreSize(I.getType()),
- AAInfo))) {
+ if (AA->pointsToConstantMemory(MemoryLocation(
+ PtrOperand, AA->getTypeStoreSize(I.getType()), AAInfo))) {
// Do not serialize (non-volatile) loads of constant memory with anything.
InChain = DAG.getEntryNode();
}
Value *BasePtr = Ptr;
bool UniformBase = getUniformBase(BasePtr, Base, Index, this);
bool ConstantMemory = false;
- if (UniformBase && AA->pointsToConstantMemory(
- AliasAnalysis::Location(BasePtr,
- AA->getTypeStoreSize(I.getType()),
- AAInfo))) {
+ if (UniformBase &&
+ AA->pointsToConstantMemory(
+ MemoryLocation(BasePtr, AA->getTypeStoreSize(I.getType()), AAInfo))) {
// Do not serialize (non-volatile) loads of constant memory with anything.
Root = DAG.getEntryNode();
ConstantMemory = true;
assert(Reg && "cannot get exception code on this platform");
MVT PtrVT = TLI.getPointerTy();
const TargetRegisterClass *PtrRC = TLI.getRegClassFor(PtrVT);
+ assert(FuncInfo.MBB->isLandingPad() && "eh.exceptioncode in non-lpad");
unsigned VReg = FuncInfo.MBB->addLiveIn(Reg, PtrRC);
SDValue N =
DAG.getCopyFromReg(DAG.getEntryNode(), getCurSDLoc(), VReg, PtrVT);
if (LandingPad) {
// Insert a label before the invoke call to mark the try range. This can be
// used to detect deletion of the invoke via the MachineModuleInfo.
- BeginLabel = MMI.getContext().CreateTempSymbol();
+ BeginLabel = MMI.getContext().createTempSymbol();
// For SjLj, keep track of which landing pads go with which invokes
// so as to maintain the ordering of pads in the LSDA.
if (LandingPad) {
// Insert a label at the end of the invoke call to mark the try range. This
// can be used to detect deletion of the invoke via the MachineModuleInfo.
- MCSymbol *EndLabel = MMI.getContext().CreateTempSymbol();
+ MCSymbol *EndLabel = MMI.getContext().createTempSymbol();
DAG.setRoot(DAG.getEHLabel(getCurSDLoc(), getRoot(), EndLabel));
// Inform MachineModuleInfo of range.
return;
}
}
- if (unsigned IID = F->getIntrinsicID()) {
+ if (Intrinsic::ID IID = F->getIntrinsicID()) {
RenameFn = visitIntrinsicCall(I, IID);
if (!RenameFn)
return;
JumpTableHeader JTH(Clusters[First].Low->getValue(),
Clusters[Last].High->getValue(), SI->getCondition(),
nullptr, false);
- JTCases.push_back(JumpTableBlock(JTH, JT));
+ JTCases.emplace_back(std::move(JTH), std::move(JT));
JTCluster = CaseCluster::jumpTable(Clusters[First].Low, Clusters[Last].High,
JTCases.size() - 1, Weight);
const int64_t N = Clusters.size();
const unsigned MinJumpTableSize = TLI.getMinimumJumpTableEntries();
+ // TotalCases[i]: Total nbr of cases in Clusters[0..i].
+ SmallVector<unsigned, 8> TotalCases(N);
+
+ for (unsigned i = 0; i < N; ++i) {
+ APInt Hi = Clusters[i].High->getValue();
+ APInt Lo = Clusters[i].Low->getValue();
+ TotalCases[i] = (Hi - Lo).getLimitedValue() + 1;
+ if (i != 0)
+ TotalCases[i] += TotalCases[i - 1];
+ }
+
+ if (N >= MinJumpTableSize && isDense(Clusters, &TotalCases[0], 0, N - 1)) {
+ // Cheap case: the whole range might be suitable for jump table.
+ CaseCluster JTCluster;
+ if (buildJumpTable(Clusters, 0, N - 1, SI, DefaultMBB, JTCluster)) {
+ Clusters[0] = JTCluster;
+ Clusters.resize(1);
+ return;
+ }
+ }
+
+ // The algorithm below is not suitable for -O0.
+ if (TM.getOptLevel() == CodeGenOpt::None)
+ return;
+
// Split Clusters into minimum number of dense partitions. The algorithm uses
// the same idea as Kannan & Proebsting "Correction to 'Producing Good Code
// for the Case Statement'" (1994), but builds the MinPartitions array in
SmallVector<unsigned, 8> LastElement(N);
// NumTables[i]: nbr of >= MinJumpTableSize partitions from Clusters[i..N-1].
SmallVector<unsigned, 8> NumTables(N);
- // TotalCases[i]: Total nbr of cases in Clusters[0..i].
- SmallVector<unsigned, 8> TotalCases(N);
-
- for (unsigned i = 0; i < N; ++i) {
- APInt Hi = Clusters[i].High->getValue();
- APInt Lo = Clusters[i].Low->getValue();
- TotalCases[i] = (Hi - Lo).getLimitedValue() + 1;
- if (i != 0)
- TotalCases[i] += TotalCases[i - 1];
- }
// Base case: There is only one way to partition Clusters[N-1].
MinPartitions[N - 1] = 1;
const int BitWidth =
DAG.getTargetLoweringInfo().getPointerTy().getSizeInBits();
- assert((High - Low + 1).sle(BitWidth) && "Case range must fit in bit mask!");
+ assert(rangeFitsInWord(Low, High) && "Case range must fit in bit mask!");
if (Low.isNonNegative() && High.slt(BitWidth)) {
// Optimize the case where all the case values fit in a
// Update Mask, Bits and ExtraWeight.
uint64_t Lo = (Clusters[i].Low->getValue() - LowBound).getZExtValue();
uint64_t Hi = (Clusters[i].High->getValue() - LowBound).getZExtValue();
- for (uint64_t j = Lo; j <= Hi; ++j) {
- CB->Mask |= 1ULL << j;
- CB->Bits++;
- }
+ assert(Hi >= Lo && Hi < 64 && "Invalid bit case!");
+ CB->Mask |= (-1ULL >> (63 - (Hi - Lo))) << Lo;
+ CB->Bits += Hi - Lo + 1;
CB->ExtraWeight += Clusters[i].Weight;
TotalWeight += Clusters[i].Weight;
assert(TotalWeight >= Clusters[i].Weight && "Weight overflow!");
FuncInfo.MF->CreateMachineBasicBlock(SI->getParent());
BTI.push_back(BitTestCase(CB.Mask, BitTestBB, CB.BB, CB.ExtraWeight));
}
- BitTestCases.push_back(BitTestBlock(LowBound, CmpRange, SI->getCondition(),
- -1U, MVT::Other, false, nullptr,
- nullptr, std::move(BTI)));
+ BitTestCases.emplace_back(std::move(LowBound), std::move(CmpRange),
+ SI->getCondition(), -1U, MVT::Other, false, nullptr,
+ nullptr, std::move(BTI));
BTCluster = CaseCluster::bitTests(Clusters[First].Low, Clusters[Last].High,
BitTestCases.size() - 1, TotalWeight);
assert(Clusters[i-1].High->getValue().slt(Clusters[i].Low->getValue()));
#endif
+ // The algorithm below is not suitable for -O0.
+ if (TM.getOptLevel() == CodeGenOpt::None)
+ return;
+
// If target does not have legal shift left, do not emit bit tests at all.
const TargetLowering &TLI = DAG.getTargetLoweringInfo();
EVT PTy = TLI.getPointerTy();
if (buildBitTests(Clusters, First, Last, SI, BitTestCluster)) {
Clusters[DstIndex++] = BitTestCluster;
} else {
- for (unsigned I = First; I <= Last; ++I)
- std::memmove(&Clusters[DstIndex++], &Clusters[I], sizeof(Clusters[I]));
+ size_t NumClusters = Last - First + 1;
+ std::memmove(&Clusters[DstIndex], &Clusters[First],
+ sizeof(Clusters[0]) * NumClusters);
+ DstIndex += NumClusters;
}
}
Clusters.resize(DstIndex);
const APInt &BigValue = Big.Low->getValue();
// Check that there is only one bit different.
- if (BigValue.countPopulation() == SmallValue.countPopulation() + 1 &&
- (SmallValue | BigValue) == BigValue) {
- // Isolate the common bit.
- APInt CommonBit = BigValue & ~SmallValue;
- assert((SmallValue | CommonBit) == BigValue &&
- CommonBit.countPopulation() == 1 && "Not a common bit?");
-
+ APInt CommonBit = BigValue ^ SmallValue;
+ if (CommonBit.isPowerOf2()) {
SDValue CondLHS = getValue(Cond);
EVT VT = CondLHS.getValueType();
SDLoc DL = getCurSDLoc();
SDValue Or = DAG.getNode(ISD::OR, DL, VT, CondLHS,
DAG.getConstant(CommonBit, DL, VT));
- SDValue Cond = DAG.getSetCC(DL, MVT::i1, Or,
- DAG.getConstant(BigValue, DL, VT),
- ISD::SETEQ);
+ SDValue Cond = DAG.getSetCC(
+ DL, MVT::i1, Or, DAG.getConstant(BigValue | SmallValue, DL, VT),
+ ISD::SETEQ);
// Update successor info.
// Both Small and Big will jump to Small.BB, so we sum up the weights.
}
}
+unsigned SelectionDAGBuilder::caseClusterRank(const CaseCluster &CC,
+ CaseClusterIt First,
+ CaseClusterIt Last) {
+ return std::count_if(First, Last + 1, [&](const CaseCluster &X) {
+ if (X.Weight != CC.Weight)
+ return X.Weight > CC.Weight;
+
+ // Ties are broken by comparing the case value.
+ return X.Low->getValue().slt(CC.Low->getValue());
+ });
+}
+
void SelectionDAGBuilder::splitWorkItem(SwitchWorkList &WorkList,
const SwitchWorkListItem &W,
Value *Cond,
RightWeight += (--FirstRight)->Weight;
I++;
}
+
+ for (;;) {
+ // Our binary search tree differs from a typical BST in that ours can have up
+ // to three values in each leaf. The pivot selection above doesn't take that
+ // into account, which means the tree might require more nodes and be less
+ // efficient. We compensate for this here.
+
+ unsigned NumLeft = LastLeft - W.FirstCluster + 1;
+ unsigned NumRight = W.LastCluster - FirstRight + 1;
+
+ if (std::min(NumLeft, NumRight) < 3 && std::max(NumLeft, NumRight) > 3) {
+ // If one side has less than 3 clusters, and the other has more than 3,
+ // consider taking a cluster from the other side.
+
+ if (NumLeft < NumRight) {
+ // Consider moving the first cluster on the right to the left side.
+ CaseCluster &CC = *FirstRight;
+ unsigned RightSideRank = caseClusterRank(CC, FirstRight, W.LastCluster);
+ unsigned LeftSideRank = caseClusterRank(CC, W.FirstCluster, LastLeft);
+ if (LeftSideRank <= RightSideRank) {
+ // Moving the cluster to the left does not demote it.
+ ++LastLeft;
+ ++FirstRight;
+ continue;
+ }
+ } else {
+ assert(NumRight < NumLeft);
+ // Consider moving the last element on the left to the right side.
+ CaseCluster &CC = *LastLeft;
+ unsigned LeftSideRank = caseClusterRank(CC, W.FirstCluster, LastLeft);
+ unsigned RightSideRank = caseClusterRank(CC, FirstRight, W.LastCluster);
+ if (RightSideRank <= LeftSideRank) {
+ // Moving the cluster to the right does not demot it.
+ --LastLeft;
+ --FirstRight;
+ continue;
+ }
+ }
+ }
+ break;
+ }
+
assert(LastLeft + 1 == FirstRight);
assert(LastLeft >= W.FirstCluster);
assert(FirstRight <= W.LastCluster);
return;
}
- if (TM.getOptLevel() != CodeGenOpt::None) {
- findJumpTables(Clusters, &SI, DefaultMBB);
- findBitTestClusters(Clusters, &SI);
- }
-
+ findJumpTables(Clusters, &SI, DefaultMBB);
+ findBitTestClusters(Clusters, &SI);
DEBUG({
dbgs() << "Case clusters: ";
projects / oota-llvm.git / blobdiff