//
//===----------------------------------------------------------------------===//
-#define DEBUG_TYPE "misched"
-
#include "llvm/CodeGen/MachineScheduler.h"
#include "llvm/ADT/PriorityQueue.h"
#include "llvm/Analysis/AliasAnalysis.h"
using namespace llvm;
+#define DEBUG_TYPE "misched"
+
namespace llvm {
cl::opt<bool> ForceTopDown("misched-topdown", cl::Hidden,
cl::desc("Force top-down list scheduling"));
cl::opt<bool> ForceBottomUp("misched-bottomup", cl::Hidden,
cl::desc("Force bottom-up list scheduling"));
+cl::opt<bool>
+DumpCriticalPathLength("misched-dcpl", cl::Hidden,
+ cl::desc("Print critical path length to stdout"));
}
#ifndef NDEBUG
static cl::opt<bool> ViewMISchedDAGs("view-misched-dags", cl::Hidden,
cl::desc("Pop up a window to show MISched dags after they are processed"));
+/// In some situations a few uninteresting nodes depend on nearly all other
+/// nodes in the graph, provide a cutoff to hide them.
+static cl::opt<unsigned> ViewMISchedCutoff("view-misched-cutoff", cl::Hidden,
+ cl::desc("Hide nodes with more predecessor/successor than cutoff"));
+
static cl::opt<unsigned> MISchedCutoff("misched-cutoff", cl::Hidden,
cl::desc("Stop scheduling after N instructions"), cl::init(~0U));
//===----------------------------------------------------------------------===//
MachineSchedContext::MachineSchedContext():
- MF(0), MLI(0), MDT(0), PassConfig(0), AA(0), LIS(0) {
+ MF(nullptr), MLI(nullptr), MDT(nullptr), PassConfig(nullptr), AA(nullptr), LIS(nullptr) {
RegClassInfo = new RegisterClassInfo();
}
public:
MachineSchedulerBase(char &ID): MachineFunctionPass(ID) {}
- void print(raw_ostream &O, const Module* = 0) const override;
+ void print(raw_ostream &O, const Module* = nullptr) const override;
protected:
void scheduleRegions(ScheduleDAGInstrs &Scheduler);
char &llvm::MachineSchedulerID = MachineScheduler::ID;
-INITIALIZE_PASS_BEGIN(MachineScheduler, "misched",
+INITIALIZE_PASS_BEGIN(MachineScheduler, "machine-scheduler",
"Machine Instruction Scheduler", false, false)
-INITIALIZE_AG_DEPENDENCY(AliasAnalysis)
+INITIALIZE_PASS_DEPENDENCY(AAResultsWrapperPass)
INITIALIZE_PASS_DEPENDENCY(SlotIndexes)
INITIALIZE_PASS_DEPENDENCY(LiveIntervals)
-INITIALIZE_PASS_END(MachineScheduler, "misched",
+INITIALIZE_PASS_END(MachineScheduler, "machine-scheduler",
"Machine Instruction Scheduler", false, false)
MachineScheduler::MachineScheduler()
AU.setPreservesCFG();
AU.addRequiredID(MachineDominatorsID);
AU.addRequired<MachineLoopInfo>();
- AU.addRequired<AliasAnalysis>();
+ AU.addRequired<AAResultsWrapperPass>();
AU.addRequired<TargetPassConfig>();
AU.addRequired<SlotIndexes>();
AU.addPreserved<SlotIndexes>();
/// A dummy default scheduler factory indicates whether the scheduler
/// is overridden on the command line.
static ScheduleDAGInstrs *useDefaultMachineSched(MachineSchedContext *C) {
- return 0;
+ return nullptr;
}
/// MachineSchedOpt allows command line selection of the scheduler.
DefaultSchedRegistry("default", "Use the target's default scheduler choice.",
useDefaultMachineSched);
+static cl::opt<bool> EnableMachineSched(
+ "enable-misched",
+ cl::desc("Enable the machine instruction scheduling pass."), cl::init(true),
+ cl::Hidden);
+
/// Forward declare the standard machine scheduler. This will be used as the
/// default scheduler if the target does not set a default.
static ScheduleDAGInstrs *createGenericSchedLive(MachineSchedContext *C);
/// design would be to split blocks at scheduling boundaries, but LLVM has a
/// general bias against block splitting purely for implementation simplicity.
bool MachineScheduler::runOnMachineFunction(MachineFunction &mf) {
+ if (EnableMachineSched.getNumOccurrences()) {
+ if (!EnableMachineSched)
+ return false;
+ } else if (!mf.getSubtarget().enableMachineScheduler())
+ return false;
+
DEBUG(dbgs() << "Before MISsched:\n"; mf.print(dbgs()));
// Initialize the context of the pass.
MLI = &getAnalysis<MachineLoopInfo>();
MDT = &getAnalysis<MachineDominatorTree>();
PassConfig = &getAnalysis<TargetPassConfig>();
- AA = &getAnalysis<AliasAnalysis>();
+ AA = &getAnalysis<AAResultsWrapperPass>().getAAResults();
LIS = &getAnalysis<LiveIntervals>();
}
bool PostMachineScheduler::runOnMachineFunction(MachineFunction &mf) {
+ if (skipOptnoneFunction(*mf.getFunction()))
+ return false;
+
+ if (!mf.getSubtarget().enablePostRAScheduler()) {
+ DEBUG(dbgs() << "Subtarget disables post-MI-sched.\n");
+ return false;
+ }
DEBUG(dbgs() << "Before post-MI-sched:\n"; mf.print(dbgs()));
// Initialize the context of the pass.
/// Main driver for both MachineScheduler and PostMachineScheduler.
void MachineSchedulerBase::scheduleRegions(ScheduleDAGInstrs &Scheduler) {
- const TargetInstrInfo *TII = MF->getTarget().getInstrInfo();
+ const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo();
bool IsPostRA = Scheduler.isPostRA();
// Visit all machine basic blocks.
// instruction stream until we find the nearest boundary.
unsigned NumRegionInstrs = 0;
MachineBasicBlock::iterator I = RegionEnd;
- for(;I != MBB->begin(); --I, --RemainingInstrs, ++NumRegionInstrs) {
+ for(;I != MBB->begin(); --I, --RemainingInstrs) {
if (isSchedBoundary(std::prev(I), MBB, MF, TII, IsPostRA))
break;
+ if (!I->isDebugValue())
+ ++NumRegionInstrs;
}
// Notify the scheduler of the region, even if we may skip scheduling
// it. Perhaps it still needs to be bundled.
else dbgs() << "End";
dbgs() << " RegionInstrs: " << NumRegionInstrs
<< " Remaining: " << RemainingInstrs << "\n");
+ if (DumpCriticalPathLength) {
+ errs() << MF->getName();
+ errs() << ":BB# " << MBB->getNumber();
+ errs() << " " << MBB->getName() << " \n";
+ }
// Schedule a region: possibly reorder instructions.
// This invalidates 'RegionEnd' and 'I'.
// unimplemented
}
-#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
+LLVM_DUMP_METHOD
void ReadyQueue::dump() {
dbgs() << Name << ": ";
for (unsigned i = 0, e = Queue.size(); i < e; ++i)
dbgs() << Queue[i]->NodeNum << " ";
dbgs() << "\n";
}
-#endif
//===----------------------------------------------------------------------===//
// ScheduleDAGMI - Basic machine instruction scheduling. This is
// virtual registers.
// ===----------------------------------------------------------------------===/
+// Provide a vtable anchor.
ScheduleDAGMI::~ScheduleDAGMI() {
- DeleteContainerPointers(Mutations);
- delete SchedImpl;
}
bool ScheduleDAGMI::canAddEdge(SUnit *SuccSU, SUnit *PredSU) {
dbgs() << "*** Scheduling failed! ***\n";
SuccSU->dump(this);
dbgs() << " has been released too many times!\n";
- llvm_unreachable(0);
+ llvm_unreachable(nullptr);
}
#endif
+ // SU->TopReadyCycle was set to CurrCycle when it was scheduled. However,
+ // CurrCycle may have advanced since then.
+ if (SuccSU->TopReadyCycle < SU->TopReadyCycle + SuccEdge->getLatency())
+ SuccSU->TopReadyCycle = SU->TopReadyCycle + SuccEdge->getLatency();
+
--SuccSU->NumPredsLeft;
if (SuccSU->NumPredsLeft == 0 && SuccSU != &ExitSU)
SchedImpl->releaseTopNode(SuccSU);
dbgs() << "*** Scheduling failed! ***\n";
PredSU->dump(this);
dbgs() << " has been released too many times!\n";
- llvm_unreachable(0);
+ llvm_unreachable(nullptr);
}
#endif
+ // SU->BotReadyCycle was set to CurrCycle when it was scheduled. However,
+ // CurrCycle may have advanced since then.
+ if (PredSU->BotReadyCycle < SU->BotReadyCycle + PredEdge->getLatency())
+ PredSU->BotReadyCycle = SU->BotReadyCycle + PredEdge->getLatency();
+
--PredSU->NumSuccsLeft;
if (PredSU->NumSuccsLeft == 0 && PredSU != &EntrySU)
SchedImpl->releaseBottomNode(PredSU);
CurrentBottom = MI;
}
}
- updateQueues(SU, IsTopNode);
-
- // Notify the scheduling strategy after updating the DAG.
+ // Notify the scheduling strategy before updating the DAG.
+ // This sets the scheduled node's ReadyCycle to CurrCycle. When updateQueues
+ // runs, it can then use the accurate ReadyCycle time to determine whether
+ // newly released nodes can move to the readyQ.
SchedImpl->schedNode(SU, IsTopNode);
+
+ updateQueues(SU, IsTopNode);
}
assert(CurrentTop == CurrentBottom && "Nonempty unscheduled zone.");
/// Identify DAG roots and setup scheduler queues.
void ScheduleDAGMI::initQueues(ArrayRef<SUnit*> TopRoots,
ArrayRef<SUnit*> BotRoots) {
- NextClusterSucc = NULL;
- NextClusterPred = NULL;
+ NextClusterSucc = nullptr;
+ NextClusterPred = nullptr;
// Release all DAG roots for scheduling, not including EntrySU/ExitSU.
//
RegionEnd = DbgValue;
}
DbgValues.clear();
- FirstDbgValue = NULL;
+ FirstDbgValue = nullptr;
}
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
DEBUG(RPTracker.dump());
// Initialize the live ins and live outs.
- TopRPTracker.addLiveRegs(RPTracker.getPressure().LiveInRegs);
- BotRPTracker.addLiveRegs(RPTracker.getPressure().LiveOutRegs);
+ TopRPTracker.addLiveRegs(RPTracker.getLiveIn());
+ BotRPTracker.addLiveRegs(RPTracker.getLiveOut());
// Close one end of the tracker so we can call
// getMaxUpward/DownwardPressureDelta before advancing across any
// For each live out vreg reduce the pressure change associated with other
// uses of the same vreg below the live-out reaching def.
- updatePressureDiffs(RPTracker.getPressure().LiveOutRegs);
+ updatePressureDiffs(RPTracker.getLiveOut());
// Account for liveness generated by the region boundary.
if (LiveRegionEnd != RegionEnd) {
unsigned Limit = RegClassInfo->getRegPressureSetLimit(ID);
if (NewMaxPressure[ID] >= Limit - 2) {
DEBUG(dbgs() << " " << TRI->getRegPressureSetName(ID) << ": "
- << NewMaxPressure[ID] << " > " << Limit << "(+ "
- << BotRPTracker.getLiveThru()[ID] << " livethru)\n");
+ << NewMaxPressure[ID]
+ << ((NewMaxPressure[ID] > Limit) ? " > " : " <= ") << Limit
+ << "(+ " << BotRPTracker.getLiveThru()[ID] << " livethru)\n");
}
}
}
/// only includes instructions that have DAG nodes, not scheduling boundaries.
///
/// This is a skeletal driver, with all the functionality pushed into helpers,
-/// so that it can be easilly extended by experimental schedulers. Generally,
+/// so that it can be easily extended by experimental schedulers. Generally,
/// implementing MachineSchedStrategy should be sufficient to implement a new
/// scheduling algorithm. However, if a scheduler further subclasses
/// ScheduleDAGMILive then it will want to override this virtual method in order
scheduleMI(SU, IsTopNode);
- updateQueues(SU, IsTopNode);
-
if (DFSResult) {
unsigned SubtreeID = DFSResult->getSubtreeID(SU);
if (!ScheduledTrees.test(SubtreeID)) {
// Notify the scheduling strategy after updating the DAG.
SchedImpl->schedNode(SU, IsTopNode);
+
+ updateQueues(SU, IsTopNode);
}
assert(CurrentTop == CurrentBottom && "Nonempty unscheduled zone.");
unsigned MaxCyclicLatency = 0;
// Visit each live out vreg def to find def/use pairs that cross iterations.
- ArrayRef<unsigned> LiveOuts = RPTracker.getPressure().LiveOutRegs;
+ ArrayRef<unsigned> LiveOuts = RPTracker.getLiveOut();
for (ArrayRef<unsigned>::iterator RI = LiveOuts.begin(), RE = LiveOuts.end();
RI != RE; ++RI) {
unsigned Reg = *RI;
SUnit *SU = Loads[Idx];
unsigned BaseReg;
unsigned Offset;
- if (TII->getLdStBaseRegImmOfs(SU->getInstr(), BaseReg, Offset, TRI))
+ if (TII->getMemOpBaseRegImmOfs(SU->getInstr(), BaseReg, Offset, TRI))
LoadRecords.push_back(LoadInfo(SU, BaseReg, Offset));
}
if (LoadRecords.size() < 2)
/// \brief Post-process the DAG to create cluster edges between instructions
/// that may be fused by the processor into a single operation.
class MacroFusion : public ScheduleDAGMutation {
- const TargetInstrInfo *TII;
+ const TargetInstrInfo &TII;
+ const TargetRegisterInfo &TRI;
public:
- MacroFusion(const TargetInstrInfo *tii): TII(tii) {}
+ MacroFusion(const TargetInstrInfo &TII, const TargetRegisterInfo &TRI)
+ : TII(TII), TRI(TRI) {}
void apply(ScheduleDAGMI *DAG) override;
};
} // anonymous
+/// Returns true if \p MI reads a register written by \p Other.
+static bool HasDataDep(const TargetRegisterInfo &TRI, const MachineInstr &MI,
+ const MachineInstr &Other) {
+ for (const MachineOperand &MO : MI.uses()) {
+ if (!MO.isReg() || !MO.readsReg())
+ continue;
+
+ unsigned Reg = MO.getReg();
+ if (Other.modifiesRegister(Reg, &TRI))
+ return true;
+ }
+ return false;
+}
+
/// \brief Callback from DAG postProcessing to create cluster edges to encourage
/// fused operations.
void MacroFusion::apply(ScheduleDAGMI *DAG) {
// For now, assume targets can only fuse with the branch.
- MachineInstr *Branch = DAG->ExitSU.getInstr();
+ SUnit &ExitSU = DAG->ExitSU;
+ MachineInstr *Branch = ExitSU.getInstr();
if (!Branch)
return;
- for (unsigned Idx = DAG->SUnits.size(); Idx > 0;) {
- SUnit *SU = &DAG->SUnits[--Idx];
- if (!TII->shouldScheduleAdjacent(SU->getInstr(), Branch))
+ for (SUnit &SU : DAG->SUnits) {
+ // SUnits with successors can't be schedule in front of the ExitSU.
+ if (!SU.Succs.empty())
+ continue;
+ // We only care if the node writes to a register that the branch reads.
+ MachineInstr *Pred = SU.getInstr();
+ if (!HasDataDep(TRI, *Branch, *Pred))
+ continue;
+
+ if (!TII.shouldScheduleAdjacent(Pred, Branch))
continue;
// Create a single weak edge from SU to ExitSU. The only effect is to cause
// scheduling cannot prioritize ExitSU anyway. To defer top-down scheduling
// of SU, we could create an artificial edge from the deepest root, but it
// hasn't been needed yet.
- bool Success = DAG->addEdge(&DAG->ExitSU, SDep(SU, SDep::Cluster));
+ bool Success = DAG->addEdge(&ExitSU, SDep(&SU, SDep::Cluster));
(void)Success;
assert(Success && "No DAG nodes should be reachable from ExitSU");
- DEBUG(dbgs() << "Macro Fuse SU(" << SU->NodeNum << ")\n");
+ DEBUG(dbgs() << "Macro Fuse SU(" << SU.NodeNum << ")\n");
break;
}
}
// Check if either the dest or source is local. If it's live across a back
// edge, it's not local. Note that if both vregs are live across the back
// edge, we cannot successfully contrain the copy without cyclic scheduling.
- unsigned LocalReg = DstReg;
- unsigned GlobalReg = SrcReg;
+ // If both the copy's source and dest are local live intervals, then we
+ // should treat the dest as the global for the purpose of adding
+ // constraints. This adds edges from source's other uses to the copy.
+ unsigned LocalReg = SrcReg;
+ unsigned GlobalReg = DstReg;
LiveInterval *LocalLI = &LIS->getInterval(LocalReg);
if (!LocalLI->isLocal(RegionBeginIdx, RegionEndIdx)) {
- LocalReg = SrcReg;
- GlobalReg = DstReg;
+ LocalReg = DstReg;
+ GlobalReg = SrcReg;
LocalLI = &LIS->getInterval(LocalReg);
if (!LocalLI->isLocal(RegionBeginIdx, RegionEndIdx))
return;
// invalid, placeholder HazardRecs.
if (HazardRec && HazardRec->isEnabled()) {
delete HazardRec;
- HazardRec = 0;
+ HazardRec = nullptr;
}
Available.clear();
Pending.clear();
// Track the maximum number of stall cycles that could arise either from the
// latency of a DAG edge or the number of cycles that a processor resource is
// reserved (SchedBoundary::ReservedCycles).
- MaxObservedLatency = 0;
+ MaxObservedStall = 0;
#endif
// Reserve a zero-count for invalid CritResIdx.
ExecutedResCounts.resize(1);
for (TargetSchedModel::ProcResIter
PI = SchedModel->getWriteProcResBegin(SC),
PE = SchedModel->getWriteProcResEnd(SC); PI != PE; ++PI) {
- if (getNextResourceCycle(PI->ProcResourceIdx, PI->Cycles) > CurrCycle)
+ unsigned NRCycle = getNextResourceCycle(PI->ProcResourceIdx, PI->Cycles);
+ if (NRCycle > CurrCycle) {
+#ifndef NDEBUG
+ MaxObservedStall = std::max(PI->Cycles, MaxObservedStall);
+#endif
+ DEBUG(dbgs() << " SU(" << SU->NodeNum << ") "
+ << SchedModel->getResourceName(PI->ProcResourceIdx)
+ << "=" << NRCycle << "c\n");
return true;
+ }
}
}
return false;
// Find the unscheduled node in ReadySUs with the highest latency.
unsigned SchedBoundary::
findMaxLatency(ArrayRef<SUnit*> ReadySUs) {
- SUnit *LateSU = 0;
+ SUnit *LateSU = nullptr;
unsigned RemLatency = 0;
for (ArrayRef<SUnit*>::iterator I = ReadySUs.begin(), E = ReadySUs.end();
I != E; ++I) {
}
void SchedBoundary::releaseNode(SUnit *SU, unsigned ReadyCycle) {
+ assert(SU->getInstr() && "Scheduled SUnit must have instr");
+
+#ifndef NDEBUG
+ // ReadyCycle was been bumped up to the CurrCycle when this node was
+ // scheduled, but CurrCycle may have been eagerly advanced immediately after
+ // scheduling, so may now be greater than ReadyCycle.
+ if (ReadyCycle > CurrCycle)
+ MaxObservedStall = std::max(ReadyCycle - CurrCycle, MaxObservedStall);
+#endif
+
if (ReadyCycle < MinReadyCycle)
MinReadyCycle = ReadyCycle;
if (SU->isScheduled)
return;
- for (SUnit::pred_iterator I = SU->Preds.begin(), E = SU->Preds.end();
- I != E; ++I) {
- if (I->isWeak())
- continue;
- unsigned PredReadyCycle = I->getSUnit()->TopReadyCycle;
- unsigned Latency = I->getLatency();
-#ifndef NDEBUG
- MaxObservedLatency = std::max(Latency, MaxObservedLatency);
-#endif
- if (SU->TopReadyCycle < PredReadyCycle + Latency)
- SU->TopReadyCycle = PredReadyCycle + Latency;
- }
releaseNode(SU, SU->TopReadyCycle);
}
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) {
- if (I->isWeak())
- continue;
- unsigned SuccReadyCycle = I->getSUnit()->BotReadyCycle;
- unsigned Latency = I->getLatency();
-#ifndef NDEBUG
- MaxObservedLatency = std::max(Latency, MaxObservedLatency);
-#endif
- if (SU->BotReadyCycle < SuccReadyCycle + Latency)
- SU->BotReadyCycle = SuccReadyCycle + Latency;
- }
releaseNode(SU, SU->BotReadyCycle);
}
PE = SchedModel->getWriteProcResEnd(SC); PI != PE; ++PI) {
unsigned PIdx = PI->ProcResourceIdx;
if (SchedModel->getProcResource(PIdx)->BufferSize == 0) {
- ReservedCycles[PIdx] = isTop() ? NextCycle + PI->Cycles : NextCycle;
-#ifndef NDEBUG
- MaxObservedLatency = std::max(PI->Cycles, MaxObservedLatency);
-#endif
+ if (isTop()) {
+ ReservedCycles[PIdx] =
+ std::max(getNextResourceCycle(PIdx, 0), NextCycle + PI->Cycles);
+ }
+ else
+ ReservedCycles[PIdx] = NextCycle;
}
}
}
}
}
for (unsigned i = 0; Available.empty(); ++i) {
- assert(i <= (HazardRec->getMaxLookAhead() + MaxObservedLatency) &&
- "permanent hazard"); (void)i;
+// FIXME: Re-enable assert once PR20057 is resolved.
+// assert(i <= (HazardRec->getMaxLookAhead() + MaxObservedStall) &&
+// "permanent hazard");
+ (void)i;
bumpCycle(CurrCycle + 1);
releasePending();
}
if (Available.size() == 1)
return *Available.begin();
- return NULL;
+ return nullptr;
}
#ifndef NDEBUG
// GenericScheduler - Generic implementation of MachineSchedStrategy.
//===----------------------------------------------------------------------===//
-namespace {
-/// Base class for GenericScheduler. This class maintains information about
-/// scheduling candidates based on TargetSchedModel making it easy to implement
-/// heuristics for either preRA or postRA scheduling.
-class GenericSchedulerBase : public MachineSchedStrategy {
-public:
- /// Represent the type of SchedCandidate found within a single queue.
- /// pickNodeBidirectional depends on these listed by decreasing priority.
- enum CandReason {
- NoCand, PhysRegCopy, RegExcess, RegCritical, Stall, Cluster, Weak, RegMax,
- ResourceReduce, ResourceDemand, BotHeightReduce, BotPathReduce,
- TopDepthReduce, TopPathReduce, NextDefUse, NodeOrder};
-
-#ifndef NDEBUG
- static const char *getReasonStr(GenericSchedulerBase::CandReason Reason);
-#endif
-
- /// Policy for scheduling the next instruction in the candidate's zone.
- struct CandPolicy {
- bool ReduceLatency;
- unsigned ReduceResIdx;
- unsigned DemandResIdx;
-
- CandPolicy(): ReduceLatency(false), ReduceResIdx(0), DemandResIdx(0) {}
- };
-
- /// Status of an instruction's critical resource consumption.
- struct SchedResourceDelta {
- // Count critical resources in the scheduled region required by SU.
- unsigned CritResources;
-
- // Count critical resources from another region consumed by SU.
- unsigned DemandedResources;
-
- SchedResourceDelta(): CritResources(0), DemandedResources(0) {}
-
- bool operator==(const SchedResourceDelta &RHS) const {
- return CritResources == RHS.CritResources
- && DemandedResources == RHS.DemandedResources;
- }
- bool operator!=(const SchedResourceDelta &RHS) const {
- return !operator==(RHS);
- }
- };
-
- /// Store the state used by GenericScheduler heuristics, required for the
- /// lifetime of one invocation of pickNode().
- struct SchedCandidate {
- CandPolicy Policy;
-
- // The best SUnit candidate.
- SUnit *SU;
-
- // The reason for this candidate.
- CandReason Reason;
-
- // Set of reasons that apply to multiple candidates.
- uint32_t RepeatReasonSet;
-
- // Register pressure values for the best candidate.
- RegPressureDelta RPDelta;
-
- // Critical resource consumption of the best candidate.
- SchedResourceDelta ResDelta;
-
- SchedCandidate(const CandPolicy &policy)
- : Policy(policy), SU(NULL), Reason(NoCand), RepeatReasonSet(0) {}
-
- bool isValid() const { return SU; }
-
- // Copy the status of another candidate without changing policy.
- void setBest(SchedCandidate &Best) {
- assert(Best.Reason != NoCand && "uninitialized Sched candidate");
- SU = Best.SU;
- Reason = Best.Reason;
- RPDelta = Best.RPDelta;
- ResDelta = Best.ResDelta;
- }
-
- bool isRepeat(CandReason R) { return RepeatReasonSet & (1 << R); }
- void setRepeat(CandReason R) { RepeatReasonSet |= (1 << R); }
-
- void initResourceDelta(const ScheduleDAGMI *DAG,
- const TargetSchedModel *SchedModel);
- };
-
-protected:
- const MachineSchedContext *Context;
- const TargetSchedModel *SchedModel;
- const TargetRegisterInfo *TRI;
-
- SchedRemainder Rem;
-protected:
- GenericSchedulerBase(const MachineSchedContext *C):
- Context(C), SchedModel(0), TRI(0) {}
-
- void setPolicy(CandPolicy &Policy, bool IsPostRA, SchedBoundary &CurrZone,
- SchedBoundary *OtherZone);
-
-#ifndef NDEBUG
- void traceCandidate(const SchedCandidate &Cand);
-#endif
-};
-} // namespace
-
void GenericSchedulerBase::SchedCandidate::
initResourceDelta(const ScheduleDAGMI *DAG,
const TargetSchedModel *SchedModel) {
bool IsPostRA,
SchedBoundary &CurrZone,
SchedBoundary *OtherZone) {
- // Apply preemptive heuristics based on the the total latency and resources
+ // Apply preemptive heuristics based on the total latency and resources
// inside and outside this zone. Potential stalls should be considered before
// following this policy.
<< GenericSchedulerBase::getReasonStr(Cand.Reason) << '\n');
}
-namespace {
-/// GenericScheduler shrinks the unscheduled zone using heuristics to balance
-/// the schedule.
-class GenericScheduler : public GenericSchedulerBase {
- ScheduleDAGMILive *DAG;
-
- // State of the top and bottom scheduled instruction boundaries.
- SchedBoundary Top;
- SchedBoundary Bot;
-
- MachineSchedPolicy RegionPolicy;
-public:
- GenericScheduler(const MachineSchedContext *C):
- GenericSchedulerBase(C), DAG(0), Top(SchedBoundary::TopQID, "TopQ"),
- Bot(SchedBoundary::BotQID, "BotQ") {}
-
- void initPolicy(MachineBasicBlock::iterator Begin,
- MachineBasicBlock::iterator End,
- unsigned NumRegionInstrs) override;
-
- bool shouldTrackPressure() const override {
- return RegionPolicy.ShouldTrackPressure;
- }
-
- void initialize(ScheduleDAGMI *dag) override;
-
- SUnit *pickNode(bool &IsTopNode) override;
-
- void schedNode(SUnit *SU, bool IsTopNode) override;
-
- void releaseTopNode(SUnit *SU) override {
- Top.releaseTopNode(SU);
- }
-
- void releaseBottomNode(SUnit *SU) override {
- Bot.releaseBottomNode(SU);
- }
-
- void registerRoots() override;
-
-protected:
- void checkAcyclicLatency();
-
- void tryCandidate(SchedCandidate &Cand,
- SchedCandidate &TryCand,
- SchedBoundary &Zone,
- const RegPressureTracker &RPTracker,
- RegPressureTracker &TempTracker);
-
- SUnit *pickNodeBidirectional(bool &IsTopNode);
-
- void pickNodeFromQueue(SchedBoundary &Zone,
- const RegPressureTracker &RPTracker,
- SchedCandidate &Candidate);
-
- void reschedulePhysRegCopies(SUnit *SU, bool isTop);
-};
-} // namespace
-
void GenericScheduler::initialize(ScheduleDAGMI *dag) {
assert(dag->hasVRegLiveness() &&
"(PreRA)GenericScheduler needs vreg liveness");
// Initialize the HazardRecognizers. If itineraries don't exist, are empty, or
// are disabled, then these HazardRecs will be disabled.
const InstrItineraryData *Itin = SchedModel->getInstrItineraries();
- const TargetMachine &TM = DAG->MF.getTarget();
if (!Top.HazardRec) {
Top.HazardRec =
- TM.getInstrInfo()->CreateTargetMIHazardRecognizer(Itin, DAG);
+ DAG->MF.getSubtarget().getInstrInfo()->CreateTargetMIHazardRecognizer(
+ Itin, DAG);
}
if (!Bot.HazardRec) {
Bot.HazardRec =
- TM.getInstrInfo()->CreateTargetMIHazardRecognizer(Itin, DAG);
+ DAG->MF.getSubtarget().getInstrInfo()->CreateTargetMIHazardRecognizer(
+ Itin, DAG);
}
}
void GenericScheduler::initPolicy(MachineBasicBlock::iterator Begin,
MachineBasicBlock::iterator End,
unsigned NumRegionInstrs) {
- const TargetMachine &TM = Context->MF->getTarget();
- const TargetLowering *TLI = TM.getTargetLowering();
+ const MachineFunction &MF = *Begin->getParent()->getParent();
+ const TargetLowering *TLI = MF.getSubtarget().getTargetLowering();
// Avoid setting up the register pressure tracker for small regions to save
// compile time. As a rough heuristic, only track pressure when the number of
RegionPolicy.OnlyBottomUp = true;
// Allow the subtarget to override default policy.
- const TargetSubtargetInfo &ST = TM.getSubtarget<TargetSubtargetInfo>();
- ST.overrideSchedPolicy(RegionPolicy, Begin, End, NumRegionInstrs);
+ MF.getSubtarget().overrideSchedPolicy(RegionPolicy, Begin, End,
+ NumRegionInstrs);
// After subtarget overrides, apply command line options.
if (!EnableRegPressure)
if ((*I)->getDepth() > Rem.CriticalPath)
Rem.CriticalPath = (*I)->getDepth();
}
- DEBUG(dbgs() << "Critical Path: " << Rem.CriticalPath << '\n');
+ DEBUG(dbgs() << "Critical Path(GS-RR ): " << Rem.CriticalPath << '\n');
+ if (DumpCriticalPathLength) {
+ errs() << "Critical Path(GS-RR ): " << Rem.CriticalPath << " \n";
+ }
if (EnableCyclicPath) {
Rem.CyclicCritPath = DAG->computeCyclicCriticalPath();
}
// If one candidate decreases and the other increases, go with it.
// Invalid candidates have UnitInc==0.
- if (tryLess(TryP.getUnitInc() < 0, CandP.getUnitInc() < 0, TryCand, Cand,
- Reason)) {
+ if (tryGreater(TryP.getUnitInc() < 0, CandP.getUnitInc() < 0, TryCand, Cand,
+ Reason)) {
return true;
}
// If the candidates are decreasing pressure, reverse priority.
TryCand, Cand, PhysRegCopy))
return;
- // Avoid exceeding the target's limit. If signed PSetID is negative, it is
- // invalid; convert it to INT_MAX to give it lowest priority.
+ // Avoid exceeding the target's limit.
if (DAG->isTrackingPressure() && tryPressure(TryCand.RPDelta.Excess,
Cand.RPDelta.Excess,
TryCand, Cand, RegExcess))
if (DAG->top() == DAG->bottom()) {
assert(Top.Available.empty() && Top.Pending.empty() &&
Bot.Available.empty() && Bot.Pending.empty() && "ReadyQ garbage");
- return NULL;
+ return nullptr;
}
SUnit *SU;
do {
/// Create the standard converging machine scheduler. This will be used as the
/// default scheduler if the target does not set a default.
static ScheduleDAGInstrs *createGenericSchedLive(MachineSchedContext *C) {
- ScheduleDAGMILive *DAG = new ScheduleDAGMILive(C, new GenericScheduler(C));
+ ScheduleDAGMILive *DAG = new ScheduleDAGMILive(C, make_unique<GenericScheduler>(C));
// Register DAG post-processors.
//
// FIXME: extend the mutation API to allow earlier mutations to instantiate
// data and pass it to later mutations. Have a single mutation that gathers
// the interesting nodes in one pass.
- DAG->addMutation(new CopyConstrain(DAG->TII, DAG->TRI));
+ DAG->addMutation(make_unique<CopyConstrain>(DAG->TII, DAG->TRI));
if (EnableLoadCluster && DAG->TII->enableClusterLoads())
- DAG->addMutation(new LoadClusterMutation(DAG->TII, DAG->TRI));
+ DAG->addMutation(make_unique<LoadClusterMutation>(DAG->TII, DAG->TRI));
if (EnableMacroFusion)
- DAG->addMutation(new MacroFusion(DAG->TII));
+ DAG->addMutation(make_unique<MacroFusion>(*DAG->TII, *DAG->TRI));
return DAG;
}
// PostGenericScheduler - Generic PostRA implementation of MachineSchedStrategy.
//===----------------------------------------------------------------------===//
-namespace {
-/// PostGenericScheduler - Interface to the scheduling algorithm used by
-/// ScheduleDAGMI.
-///
-/// Callbacks from ScheduleDAGMI:
-/// initPolicy -> initialize(DAG) -> registerRoots -> pickNode ...
-class PostGenericScheduler : public GenericSchedulerBase {
- ScheduleDAGMI *DAG;
- SchedBoundary Top;
- SmallVector<SUnit*, 8> BotRoots;
-public:
- PostGenericScheduler(const MachineSchedContext *C):
- GenericSchedulerBase(C), Top(SchedBoundary::TopQID, "TopQ") {}
-
- virtual ~PostGenericScheduler() {}
-
- void initPolicy(MachineBasicBlock::iterator Begin,
- MachineBasicBlock::iterator End,
- unsigned NumRegionInstrs) override {
- /* no configurable policy */
- };
-
- /// PostRA scheduling does not track pressure.
- bool shouldTrackPressure() const override { return false; }
-
- void initialize(ScheduleDAGMI *Dag) override {
- DAG = Dag;
- SchedModel = DAG->getSchedModel();
- TRI = DAG->TRI;
-
- Rem.init(DAG, SchedModel);
- Top.init(DAG, SchedModel, &Rem);
- BotRoots.clear();
-
- // Initialize the HazardRecognizers. If itineraries don't exist, are empty,
- // or are disabled, then these HazardRecs will be disabled.
- const InstrItineraryData *Itin = SchedModel->getInstrItineraries();
- const TargetMachine &TM = DAG->MF.getTarget();
- if (!Top.HazardRec) {
- Top.HazardRec =
- TM.getInstrInfo()->CreateTargetMIHazardRecognizer(Itin, DAG);
- }
- }
-
- void registerRoots() override;
-
- SUnit *pickNode(bool &IsTopNode) override;
-
- void scheduleTree(unsigned SubtreeID) override {
- llvm_unreachable("PostRA scheduler does not support subtree analysis.");
- }
-
- void schedNode(SUnit *SU, bool IsTopNode) override;
+void PostGenericScheduler::initialize(ScheduleDAGMI *Dag) {
+ DAG = Dag;
+ SchedModel = DAG->getSchedModel();
+ TRI = DAG->TRI;
- void releaseTopNode(SUnit *SU) override {
- Top.releaseTopNode(SU);
- }
+ Rem.init(DAG, SchedModel);
+ Top.init(DAG, SchedModel, &Rem);
+ BotRoots.clear();
- // Only called for roots.
- void releaseBottomNode(SUnit *SU) override {
- BotRoots.push_back(SU);
+ // Initialize the HazardRecognizers. If itineraries don't exist, are empty,
+ // or are disabled, then these HazardRecs will be disabled.
+ const InstrItineraryData *Itin = SchedModel->getInstrItineraries();
+ if (!Top.HazardRec) {
+ Top.HazardRec =
+ DAG->MF.getSubtarget().getInstrInfo()->CreateTargetMIHazardRecognizer(
+ Itin, DAG);
}
+}
-protected:
- void tryCandidate(SchedCandidate &Cand, SchedCandidate &TryCand);
-
- void pickNodeFromQueue(SchedCandidate &Cand);
-};
-} // namespace
void PostGenericScheduler::registerRoots() {
Rem.CriticalPath = DAG->ExitSU.getDepth();
if ((*I)->getDepth() > Rem.CriticalPath)
Rem.CriticalPath = (*I)->getDepth();
}
- DEBUG(dbgs() << "Critical Path: " << Rem.CriticalPath << '\n');
+ DEBUG(dbgs() << "Critical Path: (PGS-RR) " << Rem.CriticalPath << '\n');
+ if (DumpCriticalPathLength) {
+ errs() << "Critical Path(PGS-RR ): " << Rem.CriticalPath << " \n";
+ }
}
/// Apply a set of heursitics to a new candidate for PostRA scheduling.
SUnit *PostGenericScheduler::pickNode(bool &IsTopNode) {
if (DAG->top() == DAG->bottom()) {
assert(Top.Available.empty() && Top.Pending.empty() && "ReadyQ garbage");
- return NULL;
+ return nullptr;
}
SUnit *SU;
do {
SchedCandidate TopCand(NoPolicy);
// Set the top-down policy based on the state of the current top zone and
// the instructions outside the zone, including the bottom zone.
- setPolicy(TopCand.Policy, /*IsPostRA=*/true, Top, NULL);
+ setPolicy(TopCand.Policy, /*IsPostRA=*/true, Top, nullptr);
pickNodeFromQueue(TopCand);
assert(TopCand.Reason != NoCand && "failed to find a candidate");
tracePick(TopCand, true);
/// Create a generic scheduler with no vreg liveness or DAG mutation passes.
static ScheduleDAGInstrs *createGenericSchedPostRA(MachineSchedContext *C) {
- return new ScheduleDAGMI(C, new PostGenericScheduler(C), /*IsPostRA=*/true);
+ return new ScheduleDAGMI(C, make_unique<PostGenericScheduler>(C), /*IsPostRA=*/true);
}
//===----------------------------------------------------------------------===//
const BitVector *ScheduledTrees;
bool MaximizeILP;
- ILPOrder(bool MaxILP): DFSResult(0), ScheduledTrees(0), MaximizeILP(MaxILP) {}
+ ILPOrder(bool MaxILP)
+ : DFSResult(nullptr), ScheduledTrees(nullptr), MaximizeILP(MaxILP) {}
/// \brief Apply a less-than relation on node priority.
///
std::vector<SUnit*> ReadyQ;
public:
- ILPScheduler(bool MaximizeILP): DAG(0), Cmp(MaximizeILP) {}
+ ILPScheduler(bool MaximizeILP): DAG(nullptr), Cmp(MaximizeILP) {}
void initialize(ScheduleDAGMI *dag) override {
assert(dag->hasVRegLiveness() && "ILPScheduler needs vreg liveness");
/// Callback to select the highest priority node from the ready Q.
SUnit *pickNode(bool &IsTopNode) override {
- if (ReadyQ.empty()) return NULL;
+ if (ReadyQ.empty()) return nullptr;
std::pop_heap(ReadyQ.begin(), ReadyQ.end(), Cmp);
SUnit *SU = ReadyQ.back();
ReadyQ.pop_back();
} // namespace
static ScheduleDAGInstrs *createILPMaxScheduler(MachineSchedContext *C) {
- return new ScheduleDAGMILive(C, new ILPScheduler(true));
+ return new ScheduleDAGMILive(C, make_unique<ILPScheduler>(true));
}
static ScheduleDAGInstrs *createILPMinScheduler(MachineSchedContext *C) {
- return new ScheduleDAGMILive(C, new ILPScheduler(false));
+ return new ScheduleDAGMILive(C, make_unique<ILPScheduler>(false));
}
static MachineSchedRegistry ILPMaxRegistry(
"ilpmax", "Schedule bottom-up for max ILP", createILPMaxScheduler);
InstructionShuffler(bool alternate, bool topdown)
: IsAlternating(alternate), IsTopDown(topdown) {}
- virtual void initialize(ScheduleDAGMI*) {
+ void initialize(ScheduleDAGMI*) override {
TopQ.clear();
BottomQ.clear();
}
/// Implement MachineSchedStrategy interface.
/// -----------------------------------------
- virtual SUnit *pickNode(bool &IsTopNode) {
+ SUnit *pickNode(bool &IsTopNode) override {
SUnit *SU;
if (IsTopDown) {
do {
- if (TopQ.empty()) return NULL;
+ if (TopQ.empty()) return nullptr;
SU = TopQ.top();
TopQ.pop();
} while (SU->isScheduled);
}
else {
do {
- if (BottomQ.empty()) return NULL;
+ if (BottomQ.empty()) return nullptr;
SU = BottomQ.top();
BottomQ.pop();
} while (SU->isScheduled);
return SU;
}
- virtual void schedNode(SUnit *SU, bool IsTopNode) {}
+ void schedNode(SUnit *SU, bool IsTopNode) override {}
- virtual void releaseTopNode(SUnit *SU) {
+ void releaseTopNode(SUnit *SU) override {
TopQ.push(SU);
}
- virtual void releaseBottomNode(SUnit *SU) {
+ void releaseBottomNode(SUnit *SU) override {
BottomQ.push(SU);
}
};
bool TopDown = !ForceBottomUp;
assert((TopDown || !ForceTopDown) &&
"-misched-topdown incompatible with -misched-bottomup");
- return new ScheduleDAGMILive(C, new InstructionShuffler(Alternate, TopDown));
+ return new ScheduleDAGMILive(C, make_unique<InstructionShuffler>(Alternate, TopDown));
}
static MachineSchedRegistry ShufflerRegistry(
"shuffle", "Shuffle machine instructions alternating directions",
}
static bool isNodeHidden(const SUnit *Node) {
- return (Node->Preds.size() > 10 || Node->Succs.size() > 10);
+ if (ViewMISchedCutoff == 0)
+ return false;
+ return (Node->Preds.size() > ViewMISchedCutoff
+ || Node->Succs.size() > ViewMISchedCutoff);
}
static bool hasNodeAddressLabel(const SUnit *Node,
raw_string_ostream SS(Str);
const ScheduleDAGMI *DAG = static_cast<const ScheduleDAGMI*>(G);
const SchedDFSResult *DFS = DAG->hasVRegLiveness() ?
- static_cast<const ScheduleDAGMILive*>(G)->getDFSResult() : 0;
+ static_cast<const ScheduleDAGMILive*>(G)->getDFSResult() : nullptr;
SS << "SU:" << SU->NodeNum;
if (DFS)
SS << " I:" << DFS->getNumInstrs(SU);
std::string Str("shape=Mrecord");
const ScheduleDAGMI *DAG = static_cast<const ScheduleDAGMI*>(G);
const SchedDFSResult *DFS = DAG->hasVRegLiveness() ?
- static_cast<const ScheduleDAGMILive*>(G)->getDFSResult() : 0;
+ static_cast<const ScheduleDAGMILive*>(G)->getDFSResult() : nullptr;
if (DFS) {
Str += ",style=filled,fillcolor=\"#";
Str += DOT::getColorString(DFS->getSubtreeID(N));