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Diffstat (limited to 'contrib/llvm/lib/Target/Hexagon/HexagonMachineScheduler.cpp')
| -rw-r--r-- | contrib/llvm/lib/Target/Hexagon/HexagonMachineScheduler.cpp | 691 |
1 files changed, 691 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Target/Hexagon/HexagonMachineScheduler.cpp b/contrib/llvm/lib/Target/Hexagon/HexagonMachineScheduler.cpp new file mode 100644 index 000000000000..c94f081ab13b --- /dev/null +++ b/contrib/llvm/lib/Target/Hexagon/HexagonMachineScheduler.cpp @@ -0,0 +1,691 @@ +//===- HexagonMachineScheduler.cpp - MI Scheduler for Hexagon -------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// MachineScheduler schedules machine instructions after phi elimination. It +// preserves LiveIntervals so it can be invoked before register allocation. +// +//===----------------------------------------------------------------------===// + +#define DEBUG_TYPE "misched" + +#include "HexagonMachineScheduler.h" +#include "llvm/CodeGen/MachineLoopInfo.h" +#include "llvm/IR/Function.h" + +using namespace llvm; + +/// Platform specific modifications to DAG. +void VLIWMachineScheduler::postprocessDAG() { + SUnit* LastSequentialCall = NULL; + // Currently we only catch the situation when compare gets scheduled + // before preceding call. + for (unsigned su = 0, e = SUnits.size(); su != e; ++su) { + // Remember the call. + if (SUnits[su].getInstr()->isCall()) + LastSequentialCall = &(SUnits[su]); + // Look for a compare that defines a predicate. + else if (SUnits[su].getInstr()->isCompare() && LastSequentialCall) + SUnits[su].addPred(SDep(LastSequentialCall, SDep::Barrier)); + } +} + +/// Check if scheduling of this SU is possible +/// in the current packet. +/// It is _not_ precise (statefull), it is more like +/// another heuristic. Many corner cases are figured +/// empirically. +bool VLIWResourceModel::isResourceAvailable(SUnit *SU) { + if (!SU || !SU->getInstr()) + return false; + + // First see if the pipeline could receive this instruction + // in the current cycle. + switch (SU->getInstr()->getOpcode()) { + default: + if (!ResourcesModel->canReserveResources(SU->getInstr())) + return false; + case TargetOpcode::EXTRACT_SUBREG: + case TargetOpcode::INSERT_SUBREG: + case TargetOpcode::SUBREG_TO_REG: + case TargetOpcode::REG_SEQUENCE: + case TargetOpcode::IMPLICIT_DEF: + case TargetOpcode::COPY: + case TargetOpcode::INLINEASM: + break; + } + + // Now see if there are no other dependencies to instructions already + // in the packet. + for (unsigned i = 0, e = Packet.size(); i != e; ++i) { + if (Packet[i]->Succs.size() == 0) + continue; + for (SUnit::const_succ_iterator I = Packet[i]->Succs.begin(), + E = Packet[i]->Succs.end(); I != E; ++I) { + // Since we do not add pseudos to packets, might as well + // ignore order dependencies. + if (I->isCtrl()) + continue; + + if (I->getSUnit() == SU) + return false; + } + } + return true; +} + +/// Keep track of available resources. +bool VLIWResourceModel::reserveResources(SUnit *SU) { + bool startNewCycle = false; + // Artificially reset state. + if (!SU) { + ResourcesModel->clearResources(); + Packet.clear(); + TotalPackets++; + return false; + } + // If this SU does not fit in the packet + // start a new one. + if (!isResourceAvailable(SU)) { + ResourcesModel->clearResources(); + Packet.clear(); + TotalPackets++; + startNewCycle = true; + } + + switch (SU->getInstr()->getOpcode()) { + default: + ResourcesModel->reserveResources(SU->getInstr()); + break; + case TargetOpcode::EXTRACT_SUBREG: + case TargetOpcode::INSERT_SUBREG: + case TargetOpcode::SUBREG_TO_REG: + case TargetOpcode::REG_SEQUENCE: + case TargetOpcode::IMPLICIT_DEF: + case TargetOpcode::KILL: + case TargetOpcode::PROLOG_LABEL: + case TargetOpcode::EH_LABEL: + case TargetOpcode::COPY: + case TargetOpcode::INLINEASM: + break; + } + Packet.push_back(SU); + +#ifndef NDEBUG + DEBUG(dbgs() << "Packet[" << TotalPackets << "]:\n"); + for (unsigned i = 0, e = Packet.size(); i != e; ++i) { + DEBUG(dbgs() << "\t[" << i << "] SU("); + DEBUG(dbgs() << Packet[i]->NodeNum << ")\t"); + DEBUG(Packet[i]->getInstr()->dump()); + } +#endif + + // If packet is now full, reset the state so in the next cycle + // we start fresh. + if (Packet.size() >= SchedModel->getIssueWidth()) { + ResourcesModel->clearResources(); + Packet.clear(); + TotalPackets++; + startNewCycle = true; + } + + return startNewCycle; +} + +/// schedule - Called back from MachineScheduler::runOnMachineFunction +/// after setting up the current scheduling region. [RegionBegin, RegionEnd) +/// only includes instructions that have DAG nodes, not scheduling boundaries. +void VLIWMachineScheduler::schedule() { + DEBUG(dbgs() + << "********** MI Converging Scheduling VLIW BB#" << BB->getNumber() + << " " << BB->getName() + << " in_func " << BB->getParent()->getFunction()->getName() + << " at loop depth " << MLI.getLoopDepth(BB) + << " \n"); + + buildDAGWithRegPressure(); + + // Postprocess the DAG to add platform specific artificial dependencies. + postprocessDAG(); + + SmallVector<SUnit*, 8> TopRoots, BotRoots; + findRootsAndBiasEdges(TopRoots, BotRoots); + + // Initialize the strategy before modifying the DAG. + SchedImpl->initialize(this); + + // To view Height/Depth correctly, they should be accessed at least once. + // + // FIXME: SUnit::dumpAll always recompute depth and height now. The max + // depth/height could be computed directly from the roots and leaves. + DEBUG(unsigned maxH = 0; + for (unsigned su = 0, e = SUnits.size(); su != e; ++su) + if (SUnits[su].getHeight() > maxH) + maxH = SUnits[su].getHeight(); + dbgs() << "Max Height " << maxH << "\n";); + DEBUG(unsigned maxD = 0; + for (unsigned su = 0, e = SUnits.size(); su != e; ++su) + if (SUnits[su].getDepth() > maxD) + maxD = SUnits[su].getDepth(); + dbgs() << "Max Depth " << maxD << "\n";); + DEBUG(for (unsigned su = 0, e = SUnits.size(); su != e; ++su) + SUnits[su].dumpAll(this)); + + initQueues(TopRoots, BotRoots); + + bool IsTopNode = false; + while (SUnit *SU = SchedImpl->pickNode(IsTopNode)) { + if (!checkSchedLimit()) + break; + + scheduleMI(SU, IsTopNode); + + updateQueues(SU, IsTopNode); + } + assert(CurrentTop == CurrentBottom && "Nonempty unscheduled zone."); + + placeDebugValues(); +} + +void ConvergingVLIWScheduler::initialize(ScheduleDAGMI *dag) { + DAG = static_cast<VLIWMachineScheduler*>(dag); + SchedModel = DAG->getSchedModel(); + + Top.init(DAG, SchedModel); + Bot.init(DAG, SchedModel); + + // Initialize the HazardRecognizers. If itineraries don't exist, are empty, or + // are disabled, then these HazardRecs will be disabled. + const InstrItineraryData *Itin = DAG->getSchedModel()->getInstrItineraries(); + const TargetMachine &TM = DAG->MF.getTarget(); + delete Top.HazardRec; + delete Bot.HazardRec; + Top.HazardRec = TM.getInstrInfo()->CreateTargetMIHazardRecognizer(Itin, DAG); + Bot.HazardRec = TM.getInstrInfo()->CreateTargetMIHazardRecognizer(Itin, DAG); + + delete Top.ResourceModel; + delete Bot.ResourceModel; + Top.ResourceModel = new VLIWResourceModel(TM, DAG->getSchedModel()); + Bot.ResourceModel = new VLIWResourceModel(TM, DAG->getSchedModel()); + + assert((!llvm::ForceTopDown || !llvm::ForceBottomUp) && + "-misched-topdown incompatible with -misched-bottomup"); +} + +void ConvergingVLIWScheduler::releaseTopNode(SUnit *SU) { + if (SU->isScheduled) + return; + + for (SUnit::succ_iterator I = SU->Preds.begin(), E = SU->Preds.end(); + I != E; ++I) { + unsigned PredReadyCycle = I->getSUnit()->TopReadyCycle; + unsigned MinLatency = I->getLatency(); +#ifndef NDEBUG + Top.MaxMinLatency = std::max(MinLatency, Top.MaxMinLatency); +#endif + if (SU->TopReadyCycle < PredReadyCycle + MinLatency) + SU->TopReadyCycle = PredReadyCycle + MinLatency; + } + Top.releaseNode(SU, SU->TopReadyCycle); +} + +void ConvergingVLIWScheduler::releaseBottomNode(SUnit *SU) { + if (SU->isScheduled) + return; + + assert(SU->getInstr() && "Scheduled SUnit must have instr"); + + for (SUnit::succ_iterator I = SU->Succs.begin(), E = SU->Succs.end(); + I != E; ++I) { + unsigned SuccReadyCycle = I->getSUnit()->BotReadyCycle; + unsigned MinLatency = I->getLatency(); +#ifndef NDEBUG + Bot.MaxMinLatency = std::max(MinLatency, Bot.MaxMinLatency); +#endif + if (SU->BotReadyCycle < SuccReadyCycle + MinLatency) + SU->BotReadyCycle = SuccReadyCycle + MinLatency; + } + Bot.releaseNode(SU, SU->BotReadyCycle); +} + +/// Does this SU have a hazard within the current instruction group. +/// +/// The scheduler supports two modes of hazard recognition. The first is the +/// ScheduleHazardRecognizer API. It is a fully general hazard recognizer that +/// supports highly complicated in-order reservation tables +/// (ScoreboardHazardRecognizer) and arbitrary target-specific logic. +/// +/// The second is a streamlined mechanism that checks for hazards based on +/// simple counters that the scheduler itself maintains. It explicitly checks +/// for instruction dispatch limitations, including the number of micro-ops that +/// can dispatch per cycle. +/// +/// TODO: Also check whether the SU must start a new group. +bool ConvergingVLIWScheduler::SchedBoundary::checkHazard(SUnit *SU) { + if (HazardRec->isEnabled()) + return HazardRec->getHazardType(SU) != ScheduleHazardRecognizer::NoHazard; + + unsigned uops = SchedModel->getNumMicroOps(SU->getInstr()); + if (IssueCount + uops > SchedModel->getIssueWidth()) + return true; + + return false; +} + +void ConvergingVLIWScheduler::SchedBoundary::releaseNode(SUnit *SU, + unsigned ReadyCycle) { + if (ReadyCycle < MinReadyCycle) + MinReadyCycle = ReadyCycle; + + // Check for interlocks first. For the purpose of other heuristics, an + // instruction that cannot issue appears as if it's not in the ReadyQueue. + if (ReadyCycle > CurrCycle || checkHazard(SU)) + + Pending.push(SU); + else + Available.push(SU); +} + +/// Move the boundary of scheduled code by one cycle. +void ConvergingVLIWScheduler::SchedBoundary::bumpCycle() { + unsigned Width = SchedModel->getIssueWidth(); + IssueCount = (IssueCount <= Width) ? 0 : IssueCount - Width; + + assert(MinReadyCycle < UINT_MAX && "MinReadyCycle uninitialized"); + unsigned NextCycle = std::max(CurrCycle + 1, MinReadyCycle); + + if (!HazardRec->isEnabled()) { + // Bypass HazardRec virtual calls. + CurrCycle = NextCycle; + } else { + // Bypass getHazardType calls in case of long latency. + for (; CurrCycle != NextCycle; ++CurrCycle) { + if (isTop()) + HazardRec->AdvanceCycle(); + else + HazardRec->RecedeCycle(); + } + } + CheckPending = true; + + DEBUG(dbgs() << "*** " << Available.getName() << " cycle " + << CurrCycle << '\n'); +} + +/// Move the boundary of scheduled code by one SUnit. +void ConvergingVLIWScheduler::SchedBoundary::bumpNode(SUnit *SU) { + bool startNewCycle = false; + + // Update the reservation table. + if (HazardRec->isEnabled()) { + if (!isTop() && SU->isCall) { + // Calls are scheduled with their preceding instructions. For bottom-up + // scheduling, clear the pipeline state before emitting. + HazardRec->Reset(); + } + HazardRec->EmitInstruction(SU); + } + + // Update DFA model. + startNewCycle = ResourceModel->reserveResources(SU); + + // Check the instruction group dispatch limit. + // TODO: Check if this SU must end a dispatch group. + IssueCount += SchedModel->getNumMicroOps(SU->getInstr()); + if (startNewCycle) { + DEBUG(dbgs() << "*** Max instrs at cycle " << CurrCycle << '\n'); + bumpCycle(); + } + else + DEBUG(dbgs() << "*** IssueCount " << IssueCount + << " at cycle " << CurrCycle << '\n'); +} + +/// Release pending ready nodes in to the available queue. This makes them +/// visible to heuristics. +void ConvergingVLIWScheduler::SchedBoundary::releasePending() { + // If the available queue is empty, it is safe to reset MinReadyCycle. + if (Available.empty()) + MinReadyCycle = UINT_MAX; + + // Check to see if any of the pending instructions are ready to issue. If + // so, add them to the available queue. + for (unsigned i = 0, e = Pending.size(); i != e; ++i) { + SUnit *SU = *(Pending.begin()+i); + unsigned ReadyCycle = isTop() ? SU->TopReadyCycle : SU->BotReadyCycle; + + if (ReadyCycle < MinReadyCycle) + MinReadyCycle = ReadyCycle; + + if (ReadyCycle > CurrCycle) + continue; + + if (checkHazard(SU)) + continue; + + Available.push(SU); + Pending.remove(Pending.begin()+i); + --i; --e; + } + CheckPending = false; +} + +/// Remove SU from the ready set for this boundary. +void ConvergingVLIWScheduler::SchedBoundary::removeReady(SUnit *SU) { + if (Available.isInQueue(SU)) + Available.remove(Available.find(SU)); + else { + assert(Pending.isInQueue(SU) && "bad ready count"); + Pending.remove(Pending.find(SU)); + } +} + +/// If this queue only has one ready candidate, return it. As a side effect, +/// advance the cycle until at least one node is ready. If multiple instructions +/// are ready, return NULL. +SUnit *ConvergingVLIWScheduler::SchedBoundary::pickOnlyChoice() { + if (CheckPending) + releasePending(); + + for (unsigned i = 0; Available.empty(); ++i) { + assert(i <= (HazardRec->getMaxLookAhead() + MaxMinLatency) && + "permanent hazard"); (void)i; + ResourceModel->reserveResources(0); + bumpCycle(); + releasePending(); + } + if (Available.size() == 1) + return *Available.begin(); + return NULL; +} + +#ifndef NDEBUG +void ConvergingVLIWScheduler::traceCandidate(const char *Label, + const ReadyQueue &Q, + SUnit *SU, PressureChange P) { + dbgs() << Label << " " << Q.getName() << " "; + if (P.isValid()) + dbgs() << DAG->TRI->getRegPressureSetName(P.getPSet()) << ":" + << P.getUnitInc() << " "; + else + dbgs() << " "; + SU->dump(DAG); +} +#endif + +/// getSingleUnscheduledPred - If there is exactly one unscheduled predecessor +/// of SU, return it, otherwise return null. +static SUnit *getSingleUnscheduledPred(SUnit *SU) { + SUnit *OnlyAvailablePred = 0; + for (SUnit::const_pred_iterator I = SU->Preds.begin(), E = SU->Preds.end(); + I != E; ++I) { + SUnit &Pred = *I->getSUnit(); + if (!Pred.isScheduled) { + // We found an available, but not scheduled, predecessor. If it's the + // only one we have found, keep track of it... otherwise give up. + if (OnlyAvailablePred && OnlyAvailablePred != &Pred) + return 0; + OnlyAvailablePred = &Pred; + } + } + return OnlyAvailablePred; +} + +/// getSingleUnscheduledSucc - If there is exactly one unscheduled successor +/// of SU, return it, otherwise return null. +static SUnit *getSingleUnscheduledSucc(SUnit *SU) { + SUnit *OnlyAvailableSucc = 0; + for (SUnit::const_succ_iterator I = SU->Succs.begin(), E = SU->Succs.end(); + I != E; ++I) { + SUnit &Succ = *I->getSUnit(); + if (!Succ.isScheduled) { + // We found an available, but not scheduled, successor. If it's the + // only one we have found, keep track of it... otherwise give up. + if (OnlyAvailableSucc && OnlyAvailableSucc != &Succ) + return 0; + OnlyAvailableSucc = &Succ; + } + } + return OnlyAvailableSucc; +} + +// Constants used to denote relative importance of +// heuristic components for cost computation. +static const unsigned PriorityOne = 200; +static const unsigned PriorityTwo = 50; +static const unsigned ScaleTwo = 10; +static const unsigned FactorOne = 2; + +/// Single point to compute overall scheduling cost. +/// TODO: More heuristics will be used soon. +int ConvergingVLIWScheduler::SchedulingCost(ReadyQueue &Q, SUnit *SU, + SchedCandidate &Candidate, + RegPressureDelta &Delta, + bool verbose) { + // Initial trivial priority. + int ResCount = 1; + + // Do not waste time on a node that is already scheduled. + if (!SU || SU->isScheduled) + return ResCount; + + // Forced priority is high. + if (SU->isScheduleHigh) + ResCount += PriorityOne; + + // Critical path first. + if (Q.getID() == TopQID) { + ResCount += (SU->getHeight() * ScaleTwo); + + // If resources are available for it, multiply the + // chance of scheduling. + if (Top.ResourceModel->isResourceAvailable(SU)) + ResCount <<= FactorOne; + } else { + ResCount += (SU->getDepth() * ScaleTwo); + + // If resources are available for it, multiply the + // chance of scheduling. + if (Bot.ResourceModel->isResourceAvailable(SU)) + ResCount <<= FactorOne; + } + + unsigned NumNodesBlocking = 0; + if (Q.getID() == TopQID) { + // How many SUs does it block from scheduling? + // Look at all of the successors of this node. + // Count the number of nodes that + // this node is the sole unscheduled node for. + for (SUnit::const_succ_iterator I = SU->Succs.begin(), E = SU->Succs.end(); + I != E; ++I) + if (getSingleUnscheduledPred(I->getSUnit()) == SU) + ++NumNodesBlocking; + } else { + // How many unscheduled predecessors block this node? + for (SUnit::const_pred_iterator I = SU->Preds.begin(), E = SU->Preds.end(); + I != E; ++I) + if (getSingleUnscheduledSucc(I->getSUnit()) == SU) + ++NumNodesBlocking; + } + ResCount += (NumNodesBlocking * ScaleTwo); + + // Factor in reg pressure as a heuristic. + ResCount -= (Delta.Excess.getUnitInc()*PriorityTwo); + ResCount -= (Delta.CriticalMax.getUnitInc()*PriorityTwo); + + DEBUG(if (verbose) dbgs() << " Total(" << ResCount << ")"); + + return ResCount; +} + +/// Pick the best candidate from the top queue. +/// +/// TODO: getMaxPressureDelta results can be mostly cached for each SUnit during +/// DAG building. To adjust for the current scheduling location we need to +/// maintain the number of vreg uses remaining to be top-scheduled. +ConvergingVLIWScheduler::CandResult ConvergingVLIWScheduler:: +pickNodeFromQueue(ReadyQueue &Q, const RegPressureTracker &RPTracker, + SchedCandidate &Candidate) { + DEBUG(Q.dump()); + + // getMaxPressureDelta temporarily modifies the tracker. + RegPressureTracker &TempTracker = const_cast<RegPressureTracker&>(RPTracker); + + // BestSU remains NULL if no top candidates beat the best existing candidate. + CandResult FoundCandidate = NoCand; + for (ReadyQueue::iterator I = Q.begin(), E = Q.end(); I != E; ++I) { + RegPressureDelta RPDelta; + TempTracker.getMaxPressureDelta((*I)->getInstr(), RPDelta, + DAG->getRegionCriticalPSets(), + DAG->getRegPressure().MaxSetPressure); + + int CurrentCost = SchedulingCost(Q, *I, Candidate, RPDelta, false); + + // Initialize the candidate if needed. + if (!Candidate.SU) { + Candidate.SU = *I; + Candidate.RPDelta = RPDelta; + Candidate.SCost = CurrentCost; + FoundCandidate = NodeOrder; + continue; + } + + // Best cost. + if (CurrentCost > Candidate.SCost) { + DEBUG(traceCandidate("CCAND", Q, *I)); + Candidate.SU = *I; + Candidate.RPDelta = RPDelta; + Candidate.SCost = CurrentCost; + FoundCandidate = BestCost; + continue; + } + + // Fall through to original instruction order. + // Only consider node order if Candidate was chosen from this Q. + if (FoundCandidate == NoCand) + continue; + } + return FoundCandidate; +} + +/// Pick the best candidate node from either the top or bottom queue. +SUnit *ConvergingVLIWScheduler::pickNodeBidrectional(bool &IsTopNode) { + // Schedule as far as possible in the direction of no choice. This is most + // efficient, but also provides the best heuristics for CriticalPSets. + if (SUnit *SU = Bot.pickOnlyChoice()) { + IsTopNode = false; + return SU; + } + if (SUnit *SU = Top.pickOnlyChoice()) { + IsTopNode = true; + return SU; + } + SchedCandidate BotCand; + // Prefer bottom scheduling when heuristics are silent. + CandResult BotResult = pickNodeFromQueue(Bot.Available, + DAG->getBotRPTracker(), BotCand); + assert(BotResult != NoCand && "failed to find the first candidate"); + + // If either Q has a single candidate that provides the least increase in + // Excess pressure, we can immediately schedule from that Q. + // + // RegionCriticalPSets summarizes the pressure within the scheduled region and + // affects picking from either Q. If scheduling in one direction must + // increase pressure for one of the excess PSets, then schedule in that + // direction first to provide more freedom in the other direction. + if (BotResult == SingleExcess || BotResult == SingleCritical) { + IsTopNode = false; + return BotCand.SU; + } + // Check if the top Q has a better candidate. + SchedCandidate TopCand; + CandResult TopResult = pickNodeFromQueue(Top.Available, + DAG->getTopRPTracker(), TopCand); + assert(TopResult != NoCand && "failed to find the first candidate"); + + if (TopResult == SingleExcess || TopResult == SingleCritical) { + IsTopNode = true; + return TopCand.SU; + } + // If either Q has a single candidate that minimizes pressure above the + // original region's pressure pick it. + if (BotResult == SingleMax) { + IsTopNode = false; + return BotCand.SU; + } + if (TopResult == SingleMax) { + IsTopNode = true; + return TopCand.SU; + } + if (TopCand.SCost > BotCand.SCost) { + IsTopNode = true; + return TopCand.SU; + } + // Otherwise prefer the bottom candidate in node order. + IsTopNode = false; + return BotCand.SU; +} + +/// Pick the best node to balance the schedule. Implements MachineSchedStrategy. +SUnit *ConvergingVLIWScheduler::pickNode(bool &IsTopNode) { + if (DAG->top() == DAG->bottom()) { + assert(Top.Available.empty() && Top.Pending.empty() && + Bot.Available.empty() && Bot.Pending.empty() && "ReadyQ garbage"); + return NULL; + } + SUnit *SU; + if (llvm::ForceTopDown) { + SU = Top.pickOnlyChoice(); + if (!SU) { + SchedCandidate TopCand; + CandResult TopResult = + pickNodeFromQueue(Top.Available, DAG->getTopRPTracker(), TopCand); + assert(TopResult != NoCand && "failed to find the first candidate"); + (void)TopResult; + SU = TopCand.SU; + } + IsTopNode = true; + } else if (llvm::ForceBottomUp) { + SU = Bot.pickOnlyChoice(); + if (!SU) { + SchedCandidate BotCand; + CandResult BotResult = + pickNodeFromQueue(Bot.Available, DAG->getBotRPTracker(), BotCand); + assert(BotResult != NoCand && "failed to find the first candidate"); + (void)BotResult; + SU = BotCand.SU; + } + IsTopNode = false; + } else { + SU = pickNodeBidrectional(IsTopNode); + } + if (SU->isTopReady()) + Top.removeReady(SU); + if (SU->isBottomReady()) + Bot.removeReady(SU); + + DEBUG(dbgs() << "*** " << (IsTopNode ? "Top" : "Bottom") + << " Scheduling Instruction in cycle " + << (IsTopNode ? Top.CurrCycle : Bot.CurrCycle) << '\n'; + SU->dump(DAG)); + return SU; +} + +/// Update the scheduler's state after scheduling a node. This is the same node +/// that was just returned by pickNode(). However, VLIWMachineScheduler needs +/// to update it's state based on the current cycle before MachineSchedStrategy +/// does. +void ConvergingVLIWScheduler::schedNode(SUnit *SU, bool IsTopNode) { + if (IsTopNode) { + SU->TopReadyCycle = Top.CurrCycle; + Top.bumpNode(SU); + } else { + SU->BotReadyCycle = Bot.CurrCycle; + Bot.bumpNode(SU); + } +} |