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diff --git a/contrib/llvm/lib/CodeGen/SelectionDAG/ScheduleDAGFast.cpp b/contrib/llvm/lib/CodeGen/SelectionDAG/ScheduleDAGFast.cpp
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+//===----- ScheduleDAGFast.cpp - Fast poor list scheduler -----------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This implements a fast scheduler.
+//
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "pre-RA-sched"
+#include "ScheduleDAGSDNodes.h"
+#include "llvm/InlineAsm.h"
+#include "llvm/CodeGen/SchedulerRegistry.h"
+#include "llvm/CodeGen/SelectionDAGISel.h"
+#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/Target/TargetData.h"
+#include "llvm/Target/TargetInstrInfo.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/ADT/SmallSet.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/raw_ostream.h"
+using namespace llvm;
+
+STATISTIC(NumUnfolds, "Number of nodes unfolded");
+STATISTIC(NumDups, "Number of duplicated nodes");
+STATISTIC(NumPRCopies, "Number of physical copies");
+
+static RegisterScheduler
+ fastDAGScheduler("fast", "Fast suboptimal list scheduling",
+ createFastDAGScheduler);
+
+namespace {
+ /// FastPriorityQueue - A degenerate priority queue that considers
+ /// all nodes to have the same priority.
+ ///
+ struct FastPriorityQueue {
+ SmallVector<SUnit *, 16> Queue;
+
+ bool empty() const { return Queue.empty(); }
+
+ void push(SUnit *U) {
+ Queue.push_back(U);
+ }
+
+ SUnit *pop() {
+ if (empty()) return NULL;
+ SUnit *V = Queue.back();
+ Queue.pop_back();
+ return V;
+ }
+ };
+
+//===----------------------------------------------------------------------===//
+/// ScheduleDAGFast - The actual "fast" list scheduler implementation.
+///
+class ScheduleDAGFast : public ScheduleDAGSDNodes {
+private:
+ /// AvailableQueue - The priority queue to use for the available SUnits.
+ FastPriorityQueue AvailableQueue;
+
+ /// LiveRegDefs - A set of physical registers and their definition
+ /// that are "live". These nodes must be scheduled before any other nodes that
+ /// modifies the registers can be scheduled.
+ unsigned NumLiveRegs;
+ std::vector<SUnit*> LiveRegDefs;
+ std::vector<unsigned> LiveRegCycles;
+
+public:
+ ScheduleDAGFast(MachineFunction &mf)
+ : ScheduleDAGSDNodes(mf) {}
+
+ void Schedule();
+
+ /// AddPred - adds a predecessor edge to SUnit SU.
+ /// This returns true if this is a new predecessor.
+ void AddPred(SUnit *SU, const SDep &D) {
+ SU->addPred(D);
+ }
+
+ /// RemovePred - removes a predecessor edge from SUnit SU.
+ /// This returns true if an edge was removed.
+ void RemovePred(SUnit *SU, const SDep &D) {
+ SU->removePred(D);
+ }
+
+private:
+ void ReleasePred(SUnit *SU, SDep *PredEdge);
+ void ReleasePredecessors(SUnit *SU, unsigned CurCycle);
+ void ScheduleNodeBottomUp(SUnit*, unsigned);
+ SUnit *CopyAndMoveSuccessors(SUnit*);
+ void InsertCopiesAndMoveSuccs(SUnit*, unsigned,
+ const TargetRegisterClass*,
+ const TargetRegisterClass*,
+ SmallVector<SUnit*, 2>&);
+ bool DelayForLiveRegsBottomUp(SUnit*, SmallVector<unsigned, 4>&);
+ void ListScheduleBottomUp();
+
+ /// ForceUnitLatencies - The fast scheduler doesn't care about real latencies.
+ bool ForceUnitLatencies() const { return true; }
+};
+} // end anonymous namespace
+
+
+/// Schedule - Schedule the DAG using list scheduling.
+void ScheduleDAGFast::Schedule() {
+ DEBUG(dbgs() << "********** List Scheduling **********\n");
+
+ NumLiveRegs = 0;
+ LiveRegDefs.resize(TRI->getNumRegs(), NULL);
+ LiveRegCycles.resize(TRI->getNumRegs(), 0);
+
+ // Build the scheduling graph.
+ BuildSchedGraph(NULL);
+
+ DEBUG(for (unsigned su = 0, e = SUnits.size(); su != e; ++su)
+ SUnits[su].dumpAll(this));
+
+ // Execute the actual scheduling loop.
+ ListScheduleBottomUp();
+}
+
+//===----------------------------------------------------------------------===//
+// Bottom-Up Scheduling
+//===----------------------------------------------------------------------===//
+
+/// ReleasePred - Decrement the NumSuccsLeft count of a predecessor. Add it to
+/// the AvailableQueue if the count reaches zero. Also update its cycle bound.
+void ScheduleDAGFast::ReleasePred(SUnit *SU, SDep *PredEdge) {
+ SUnit *PredSU = PredEdge->getSUnit();
+
+#ifndef NDEBUG
+ if (PredSU->NumSuccsLeft == 0) {
+ dbgs() << "*** Scheduling failed! ***\n";
+ PredSU->dump(this);
+ dbgs() << " has been released too many times!\n";
+ llvm_unreachable(0);
+ }
+#endif
+ --PredSU->NumSuccsLeft;
+
+ // If all the node's successors are scheduled, this node is ready
+ // to be scheduled. Ignore the special EntrySU node.
+ if (PredSU->NumSuccsLeft == 0 && PredSU != &EntrySU) {
+ PredSU->isAvailable = true;
+ AvailableQueue.push(PredSU);
+ }
+}
+
+void ScheduleDAGFast::ReleasePredecessors(SUnit *SU, unsigned CurCycle) {
+ // Bottom up: release predecessors
+ for (SUnit::pred_iterator I = SU->Preds.begin(), E = SU->Preds.end();
+ I != E; ++I) {
+ ReleasePred(SU, &*I);
+ if (I->isAssignedRegDep()) {
+ // This is a physical register dependency and it's impossible or
+ // expensive to copy the register. Make sure nothing that can
+ // clobber the register is scheduled between the predecessor and
+ // this node.
+ if (!LiveRegDefs[I->getReg()]) {
+ ++NumLiveRegs;
+ LiveRegDefs[I->getReg()] = I->getSUnit();
+ LiveRegCycles[I->getReg()] = CurCycle;
+ }
+ }
+ }
+}
+
+/// ScheduleNodeBottomUp - Add the node to the schedule. Decrement the pending
+/// count of its predecessors. If a predecessor pending count is zero, add it to
+/// the Available queue.
+void ScheduleDAGFast::ScheduleNodeBottomUp(SUnit *SU, unsigned CurCycle) {
+ DEBUG(dbgs() << "*** Scheduling [" << CurCycle << "]: ");
+ DEBUG(SU->dump(this));
+
+ assert(CurCycle >= SU->getHeight() && "Node scheduled below its height!");
+ SU->setHeightToAtLeast(CurCycle);
+ Sequence.push_back(SU);
+
+ ReleasePredecessors(SU, CurCycle);
+
+ // Release all the implicit physical register defs that are live.
+ for (SUnit::succ_iterator I = SU->Succs.begin(), E = SU->Succs.end();
+ I != E; ++I) {
+ if (I->isAssignedRegDep()) {
+ if (LiveRegCycles[I->getReg()] == I->getSUnit()->getHeight()) {
+ assert(NumLiveRegs > 0 && "NumLiveRegs is already zero!");
+ assert(LiveRegDefs[I->getReg()] == SU &&
+ "Physical register dependency violated?");
+ --NumLiveRegs;
+ LiveRegDefs[I->getReg()] = NULL;
+ LiveRegCycles[I->getReg()] = 0;
+ }
+ }
+ }
+
+ SU->isScheduled = true;
+}
+
+/// CopyAndMoveSuccessors - Clone the specified node and move its scheduled
+/// successors to the newly created node.
+SUnit *ScheduleDAGFast::CopyAndMoveSuccessors(SUnit *SU) {
+ if (SU->getNode()->getGluedNode())
+ return NULL;
+
+ SDNode *N = SU->getNode();
+ if (!N)
+ return NULL;
+
+ SUnit *NewSU;
+ bool TryUnfold = false;
+ for (unsigned i = 0, e = N->getNumValues(); i != e; ++i) {
+ EVT VT = N->getValueType(i);
+ if (VT == MVT::Glue)
+ return NULL;
+ else if (VT == MVT::Other)
+ TryUnfold = true;
+ }
+ for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
+ const SDValue &Op = N->getOperand(i);
+ EVT VT = Op.getNode()->getValueType(Op.getResNo());
+ if (VT == MVT::Glue)
+ return NULL;
+ }
+
+ if (TryUnfold) {
+ SmallVector<SDNode*, 2> NewNodes;
+ if (!TII->unfoldMemoryOperand(*DAG, N, NewNodes))
+ return NULL;
+
+ DEBUG(dbgs() << "Unfolding SU # " << SU->NodeNum << "\n");
+ assert(NewNodes.size() == 2 && "Expected a load folding node!");
+
+ N = NewNodes[1];
+ SDNode *LoadNode = NewNodes[0];
+ unsigned NumVals = N->getNumValues();
+ unsigned OldNumVals = SU->getNode()->getNumValues();
+ for (unsigned i = 0; i != NumVals; ++i)
+ DAG->ReplaceAllUsesOfValueWith(SDValue(SU->getNode(), i), SDValue(N, i));
+ DAG->ReplaceAllUsesOfValueWith(SDValue(SU->getNode(), OldNumVals-1),
+ SDValue(LoadNode, 1));
+
+ SUnit *NewSU = NewSUnit(N);
+ assert(N->getNodeId() == -1 && "Node already inserted!");
+ N->setNodeId(NewSU->NodeNum);
+
+ const MCInstrDesc &MCID = TII->get(N->getMachineOpcode());
+ for (unsigned i = 0; i != MCID.getNumOperands(); ++i) {
+ if (MCID.getOperandConstraint(i, MCOI::TIED_TO) != -1) {
+ NewSU->isTwoAddress = true;
+ break;
+ }
+ }
+ if (MCID.isCommutable())
+ NewSU->isCommutable = true;
+
+ // LoadNode may already exist. This can happen when there is another
+ // load from the same location and producing the same type of value
+ // but it has different alignment or volatileness.
+ bool isNewLoad = true;
+ SUnit *LoadSU;
+ if (LoadNode->getNodeId() != -1) {
+ LoadSU = &SUnits[LoadNode->getNodeId()];
+ isNewLoad = false;
+ } else {
+ LoadSU = NewSUnit(LoadNode);
+ LoadNode->setNodeId(LoadSU->NodeNum);
+ }
+
+ SDep ChainPred;
+ SmallVector<SDep, 4> ChainSuccs;
+ SmallVector<SDep, 4> LoadPreds;
+ SmallVector<SDep, 4> NodePreds;
+ SmallVector<SDep, 4> NodeSuccs;
+ for (SUnit::pred_iterator I = SU->Preds.begin(), E = SU->Preds.end();
+ I != E; ++I) {
+ if (I->isCtrl())
+ ChainPred = *I;
+ else if (I->getSUnit()->getNode() &&
+ I->getSUnit()->getNode()->isOperandOf(LoadNode))
+ LoadPreds.push_back(*I);
+ else
+ NodePreds.push_back(*I);
+ }
+ for (SUnit::succ_iterator I = SU->Succs.begin(), E = SU->Succs.end();
+ I != E; ++I) {
+ if (I->isCtrl())
+ ChainSuccs.push_back(*I);
+ else
+ NodeSuccs.push_back(*I);
+ }
+
+ if (ChainPred.getSUnit()) {
+ RemovePred(SU, ChainPred);
+ if (isNewLoad)
+ AddPred(LoadSU, ChainPred);
+ }
+ for (unsigned i = 0, e = LoadPreds.size(); i != e; ++i) {
+ const SDep &Pred = LoadPreds[i];
+ RemovePred(SU, Pred);
+ if (isNewLoad) {
+ AddPred(LoadSU, Pred);
+ }
+ }
+ for (unsigned i = 0, e = NodePreds.size(); i != e; ++i) {
+ const SDep &Pred = NodePreds[i];
+ RemovePred(SU, Pred);
+ AddPred(NewSU, Pred);
+ }
+ for (unsigned i = 0, e = NodeSuccs.size(); i != e; ++i) {
+ SDep D = NodeSuccs[i];
+ SUnit *SuccDep = D.getSUnit();
+ D.setSUnit(SU);
+ RemovePred(SuccDep, D);
+ D.setSUnit(NewSU);
+ AddPred(SuccDep, D);
+ }
+ for (unsigned i = 0, e = ChainSuccs.size(); i != e; ++i) {
+ SDep D = ChainSuccs[i];
+ SUnit *SuccDep = D.getSUnit();
+ D.setSUnit(SU);
+ RemovePred(SuccDep, D);
+ if (isNewLoad) {
+ D.setSUnit(LoadSU);
+ AddPred(SuccDep, D);
+ }
+ }
+ if (isNewLoad) {
+ AddPred(NewSU, SDep(LoadSU, SDep::Order, LoadSU->Latency));
+ }
+
+ ++NumUnfolds;
+
+ if (NewSU->NumSuccsLeft == 0) {
+ NewSU->isAvailable = true;
+ return NewSU;
+ }
+ SU = NewSU;
+ }
+
+ DEBUG(dbgs() << "Duplicating SU # " << SU->NodeNum << "\n");
+ NewSU = Clone(SU);
+
+ // New SUnit has the exact same predecessors.
+ for (SUnit::pred_iterator I = SU->Preds.begin(), E = SU->Preds.end();
+ I != E; ++I)
+ if (!I->isArtificial())
+ AddPred(NewSU, *I);
+
+ // Only copy scheduled successors. Cut them from old node's successor
+ // list and move them over.
+ SmallVector<std::pair<SUnit *, SDep>, 4> DelDeps;
+ for (SUnit::succ_iterator I = SU->Succs.begin(), E = SU->Succs.end();
+ I != E; ++I) {
+ if (I->isArtificial())
+ continue;
+ SUnit *SuccSU = I->getSUnit();
+ if (SuccSU->isScheduled) {
+ SDep D = *I;
+ D.setSUnit(NewSU);
+ AddPred(SuccSU, D);
+ D.setSUnit(SU);
+ DelDeps.push_back(std::make_pair(SuccSU, D));
+ }
+ }
+ for (unsigned i = 0, e = DelDeps.size(); i != e; ++i)
+ RemovePred(DelDeps[i].first, DelDeps[i].second);
+
+ ++NumDups;
+ return NewSU;
+}
+
+/// InsertCopiesAndMoveSuccs - Insert register copies and move all
+/// scheduled successors of the given SUnit to the last copy.
+void ScheduleDAGFast::InsertCopiesAndMoveSuccs(SUnit *SU, unsigned Reg,
+ const TargetRegisterClass *DestRC,
+ const TargetRegisterClass *SrcRC,
+ SmallVector<SUnit*, 2> &Copies) {
+ SUnit *CopyFromSU = NewSUnit(static_cast<SDNode *>(NULL));
+ CopyFromSU->CopySrcRC = SrcRC;
+ CopyFromSU->CopyDstRC = DestRC;
+
+ SUnit *CopyToSU = NewSUnit(static_cast<SDNode *>(NULL));
+ CopyToSU->CopySrcRC = DestRC;
+ CopyToSU->CopyDstRC = SrcRC;
+
+ // Only copy scheduled successors. Cut them from old node's successor
+ // list and move them over.
+ SmallVector<std::pair<SUnit *, SDep>, 4> DelDeps;
+ for (SUnit::succ_iterator I = SU->Succs.begin(), E = SU->Succs.end();
+ I != E; ++I) {
+ if (I->isArtificial())
+ continue;
+ SUnit *SuccSU = I->getSUnit();
+ if (SuccSU->isScheduled) {
+ SDep D = *I;
+ D.setSUnit(CopyToSU);
+ AddPred(SuccSU, D);
+ DelDeps.push_back(std::make_pair(SuccSU, *I));
+ }
+ }
+ for (unsigned i = 0, e = DelDeps.size(); i != e; ++i) {
+ RemovePred(DelDeps[i].first, DelDeps[i].second);
+ }
+
+ AddPred(CopyFromSU, SDep(SU, SDep::Data, SU->Latency, Reg));
+ AddPred(CopyToSU, SDep(CopyFromSU, SDep::Data, CopyFromSU->Latency, 0));
+
+ Copies.push_back(CopyFromSU);
+ Copies.push_back(CopyToSU);
+
+ ++NumPRCopies;
+}
+
+/// getPhysicalRegisterVT - Returns the ValueType of the physical register
+/// definition of the specified node.
+/// FIXME: Move to SelectionDAG?
+static EVT getPhysicalRegisterVT(SDNode *N, unsigned Reg,
+ const TargetInstrInfo *TII) {
+ const MCInstrDesc &MCID = TII->get(N->getMachineOpcode());
+ assert(MCID.ImplicitDefs && "Physical reg def must be in implicit def list!");
+ unsigned NumRes = MCID.getNumDefs();
+ for (const unsigned *ImpDef = MCID.getImplicitDefs(); *ImpDef; ++ImpDef) {
+ if (Reg == *ImpDef)
+ break;
+ ++NumRes;
+ }
+ return N->getValueType(NumRes);
+}
+
+/// CheckForLiveRegDef - Return true and update live register vector if the
+/// specified register def of the specified SUnit clobbers any "live" registers.
+static bool CheckForLiveRegDef(SUnit *SU, unsigned Reg,
+ std::vector<SUnit*> &LiveRegDefs,
+ SmallSet<unsigned, 4> &RegAdded,
+ SmallVector<unsigned, 4> &LRegs,
+ const TargetRegisterInfo *TRI) {
+ bool Added = false;
+ if (LiveRegDefs[Reg] && LiveRegDefs[Reg] != SU) {
+ if (RegAdded.insert(Reg)) {
+ LRegs.push_back(Reg);
+ Added = true;
+ }
+ }
+ for (const unsigned *Alias = TRI->getAliasSet(Reg); *Alias; ++Alias)
+ if (LiveRegDefs[*Alias] && LiveRegDefs[*Alias] != SU) {
+ if (RegAdded.insert(*Alias)) {
+ LRegs.push_back(*Alias);
+ Added = true;
+ }
+ }
+ return Added;
+}
+
+/// DelayForLiveRegsBottomUp - Returns true if it is necessary to delay
+/// scheduling of the given node to satisfy live physical register dependencies.
+/// If the specific node is the last one that's available to schedule, do
+/// whatever is necessary (i.e. backtracking or cloning) to make it possible.
+bool ScheduleDAGFast::DelayForLiveRegsBottomUp(SUnit *SU,
+ SmallVector<unsigned, 4> &LRegs){
+ if (NumLiveRegs == 0)
+ return false;
+
+ SmallSet<unsigned, 4> RegAdded;
+ // If this node would clobber any "live" register, then it's not ready.
+ for (SUnit::pred_iterator I = SU->Preds.begin(), E = SU->Preds.end();
+ I != E; ++I) {
+ if (I->isAssignedRegDep()) {
+ CheckForLiveRegDef(I->getSUnit(), I->getReg(), LiveRegDefs,
+ RegAdded, LRegs, TRI);
+ }
+ }
+
+ for (SDNode *Node = SU->getNode(); Node; Node = Node->getGluedNode()) {
+ if (Node->getOpcode() == ISD::INLINEASM) {
+ // Inline asm can clobber physical defs.
+ unsigned NumOps = Node->getNumOperands();
+ if (Node->getOperand(NumOps-1).getValueType() == MVT::Glue)
+ --NumOps; // Ignore the glue operand.
+
+ for (unsigned i = InlineAsm::Op_FirstOperand; i != NumOps;) {
+ unsigned Flags =
+ cast<ConstantSDNode>(Node->getOperand(i))->getZExtValue();
+ unsigned NumVals = InlineAsm::getNumOperandRegisters(Flags);
+
+ ++i; // Skip the ID value.
+ if (InlineAsm::isRegDefKind(Flags) ||
+ InlineAsm::isRegDefEarlyClobberKind(Flags) ||
+ InlineAsm::isClobberKind(Flags)) {
+ // Check for def of register or earlyclobber register.
+ for (; NumVals; --NumVals, ++i) {
+ unsigned Reg = cast<RegisterSDNode>(Node->getOperand(i))->getReg();
+ if (TargetRegisterInfo::isPhysicalRegister(Reg))
+ CheckForLiveRegDef(SU, Reg, LiveRegDefs, RegAdded, LRegs, TRI);
+ }
+ } else
+ i += NumVals;
+ }
+ continue;
+ }
+ if (!Node->isMachineOpcode())
+ continue;
+ const MCInstrDesc &MCID = TII->get(Node->getMachineOpcode());
+ if (!MCID.ImplicitDefs)
+ continue;
+ for (const unsigned *Reg = MCID.ImplicitDefs; *Reg; ++Reg) {
+ CheckForLiveRegDef(SU, *Reg, LiveRegDefs, RegAdded, LRegs, TRI);
+ }
+ }
+ return !LRegs.empty();
+}
+
+
+/// ListScheduleBottomUp - The main loop of list scheduling for bottom-up
+/// schedulers.
+void ScheduleDAGFast::ListScheduleBottomUp() {
+ unsigned CurCycle = 0;
+
+ // Release any predecessors of the special Exit node.
+ ReleasePredecessors(&ExitSU, CurCycle);
+
+ // Add root to Available queue.
+ if (!SUnits.empty()) {
+ SUnit *RootSU = &SUnits[DAG->getRoot().getNode()->getNodeId()];
+ assert(RootSU->Succs.empty() && "Graph root shouldn't have successors!");
+ RootSU->isAvailable = true;
+ AvailableQueue.push(RootSU);
+ }
+
+ // While Available queue is not empty, grab the node with the highest
+ // priority. If it is not ready put it back. Schedule the node.
+ SmallVector<SUnit*, 4> NotReady;
+ DenseMap<SUnit*, SmallVector<unsigned, 4> > LRegsMap;
+ Sequence.reserve(SUnits.size());
+ while (!AvailableQueue.empty()) {
+ bool Delayed = false;
+ LRegsMap.clear();
+ SUnit *CurSU = AvailableQueue.pop();
+ while (CurSU) {
+ SmallVector<unsigned, 4> LRegs;
+ if (!DelayForLiveRegsBottomUp(CurSU, LRegs))
+ break;
+ Delayed = true;
+ LRegsMap.insert(std::make_pair(CurSU, LRegs));
+
+ CurSU->isPending = true; // This SU is not in AvailableQueue right now.
+ NotReady.push_back(CurSU);
+ CurSU = AvailableQueue.pop();
+ }
+
+ // All candidates are delayed due to live physical reg dependencies.
+ // Try code duplication or inserting cross class copies
+ // to resolve it.
+ if (Delayed && !CurSU) {
+ if (!CurSU) {
+ // Try duplicating the nodes that produces these
+ // "expensive to copy" values to break the dependency. In case even
+ // that doesn't work, insert cross class copies.
+ SUnit *TrySU = NotReady[0];
+ SmallVector<unsigned, 4> &LRegs = LRegsMap[TrySU];
+ assert(LRegs.size() == 1 && "Can't handle this yet!");
+ unsigned Reg = LRegs[0];
+ SUnit *LRDef = LiveRegDefs[Reg];
+ EVT VT = getPhysicalRegisterVT(LRDef->getNode(), Reg, TII);
+ const TargetRegisterClass *RC =
+ TRI->getMinimalPhysRegClass(Reg, VT);
+ const TargetRegisterClass *DestRC = TRI->getCrossCopyRegClass(RC);
+
+ // If cross copy register class is the same as RC, then it must be
+ // possible copy the value directly. Do not try duplicate the def.
+ // If cross copy register class is not the same as RC, then it's
+ // possible to copy the value but it require cross register class copies
+ // and it is expensive.
+ // If cross copy register class is null, then it's not possible to copy
+ // the value at all.
+ SUnit *NewDef = 0;
+ if (DestRC != RC) {
+ NewDef = CopyAndMoveSuccessors(LRDef);
+ if (!DestRC && !NewDef)
+ report_fatal_error("Can't handle live physical "
+ "register dependency!");
+ }
+ if (!NewDef) {
+ // Issue copies, these can be expensive cross register class copies.
+ SmallVector<SUnit*, 2> Copies;
+ InsertCopiesAndMoveSuccs(LRDef, Reg, DestRC, RC, Copies);
+ DEBUG(dbgs() << "Adding an edge from SU # " << TrySU->NodeNum
+ << " to SU #" << Copies.front()->NodeNum << "\n");
+ AddPred(TrySU, SDep(Copies.front(), SDep::Order, /*Latency=*/1,
+ /*Reg=*/0, /*isNormalMemory=*/false,
+ /*isMustAlias=*/false, /*isArtificial=*/true));
+ NewDef = Copies.back();
+ }
+
+ DEBUG(dbgs() << "Adding an edge from SU # " << NewDef->NodeNum
+ << " to SU #" << TrySU->NodeNum << "\n");
+ LiveRegDefs[Reg] = NewDef;
+ AddPred(NewDef, SDep(TrySU, SDep::Order, /*Latency=*/1,
+ /*Reg=*/0, /*isNormalMemory=*/false,
+ /*isMustAlias=*/false, /*isArtificial=*/true));
+ TrySU->isAvailable = false;
+ CurSU = NewDef;
+ }
+
+ if (!CurSU) {
+ llvm_unreachable("Unable to resolve live physical register dependencies!");
+ }
+ }
+
+ // Add the nodes that aren't ready back onto the available list.
+ for (unsigned i = 0, e = NotReady.size(); i != e; ++i) {
+ NotReady[i]->isPending = false;
+ // May no longer be available due to backtracking.
+ if (NotReady[i]->isAvailable)
+ AvailableQueue.push(NotReady[i]);
+ }
+ NotReady.clear();
+
+ if (CurSU)
+ ScheduleNodeBottomUp(CurSU, CurCycle);
+ ++CurCycle;
+ }
+
+ // Reverse the order since it is bottom up.
+ std::reverse(Sequence.begin(), Sequence.end());
+
+#ifndef NDEBUG
+ VerifySchedule(/*isBottomUp=*/true);
+#endif
+}
+
+//===----------------------------------------------------------------------===//
+// Public Constructor Functions
+//===----------------------------------------------------------------------===//
+
+llvm::ScheduleDAGSDNodes *
+llvm::createFastDAGScheduler(SelectionDAGISel *IS, CodeGenOpt::Level) {
+ return new ScheduleDAGFast(*IS->MF);
+}
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