LLVM
8.0.1
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ScheduleDAGMI is an implementation of ScheduleDAGInstrs that simply schedules machine instructions according to the given MachineSchedStrategy without much extra book-keeping. More...
#include "llvm/CodeGen/MachineScheduler.h"
Public Member Functions | |
ScheduleDAGMI (MachineSchedContext *C, std::unique_ptr< MachineSchedStrategy > S, bool RemoveKillFlags) | |
~ScheduleDAGMI () override | |
bool | doMBBSchedRegionsTopDown () const override |
If this method returns true, handling of the scheduling regions themselves (in case of a scheduling boundary in MBB) will be done beginning with the topmost region of MBB. More... | |
LiveIntervals * | getLIS () const |
virtual bool | hasVRegLiveness () const |
Return true if this DAG supports VReg liveness and RegPressure. More... | |
void | addMutation (std::unique_ptr< ScheduleDAGMutation > Mutation) |
Add a postprocessing step to the DAG builder. More... | |
bool | canAddEdge (SUnit *SuccSU, SUnit *PredSU) |
True if an edge can be added from PredSU to SuccSU without creating a cycle. More... | |
bool | addEdge (SUnit *SuccSU, const SDep &PredDep) |
Add a DAG edge to the given SU with the given predecessor dependence data. More... | |
MachineBasicBlock::iterator | top () const |
MachineBasicBlock::iterator | bottom () const |
void | enterRegion (MachineBasicBlock *bb, MachineBasicBlock::iterator begin, MachineBasicBlock::iterator end, unsigned regioninstrs) override |
Implement the ScheduleDAGInstrs interface for handling the next scheduling region. More... | |
void | schedule () override |
Implement ScheduleDAGInstrs interface for scheduling a sequence of reorderable instructions. More... | |
void | startBlock (MachineBasicBlock *bb) override |
Prepares to perform scheduling in the given block. More... | |
void | finishBlock () override |
Cleans up after scheduling in the given block. More... | |
void | moveInstruction (MachineInstr *MI, MachineBasicBlock::iterator InsertPos) |
Change the position of an instruction within the basic block and update live ranges and region boundary iterators. More... | |
const SUnit * | getNextClusterPred () const |
const SUnit * | getNextClusterSucc () const |
void | viewGraph (const Twine &Name, const Twine &Title) override |
viewGraph - Pop up a ghostview window with the reachable parts of the DAG rendered using 'dot'. More... | |
void | viewGraph () override |
Out-of-line implementation with no arguments is handy for gdb. More... | |
Public Member Functions inherited from llvm::ScheduleDAGInstrs | |
ScheduleDAGInstrs (MachineFunction &mf, const MachineLoopInfo *mli, bool RemoveKillFlags=false) | |
~ScheduleDAGInstrs () override=default | |
const TargetSchedModel * | getSchedModel () const |
Gets the machine model for instruction scheduling. More... | |
const MCSchedClassDesc * | getSchedClass (SUnit *SU) const |
Resolves and cache a resolved scheduling class for an SUnit. More... | |
MachineBasicBlock::iterator | begin () const |
Returns an iterator to the top of the current scheduling region. More... | |
MachineBasicBlock::iterator | end () const |
Returns an iterator to the bottom of the current scheduling region. More... | |
SUnit * | newSUnit (MachineInstr *MI) |
Creates a new SUnit and return a ptr to it. More... | |
SUnit * | getSUnit (MachineInstr *MI) const |
Returns an existing SUnit for this MI, or nullptr. More... | |
virtual void | exitRegion () |
Called when the scheduler has finished scheduling the current region. More... | |
void | buildSchedGraph (AliasAnalysis *AA, RegPressureTracker *RPTracker=nullptr, PressureDiffs *PDiffs=nullptr, LiveIntervals *LIS=nullptr, bool TrackLaneMasks=false) |
Builds SUnits for the current region. More... | |
void | addSchedBarrierDeps () |
Adds dependencies from instructions in the current list of instructions being scheduled to scheduling barrier. More... | |
virtual void | finalizeSchedule () |
Allow targets to perform final scheduling actions at the level of the whole MachineFunction. More... | |
void | dumpNode (const SUnit &SU) const override |
void | dump () const override |
std::string | getGraphNodeLabel (const SUnit *SU) const override |
Returns a label for a DAG node that points to an instruction. More... | |
std::string | getDAGName () const override |
Returns a label for the region of code covered by the DAG. More... | |
void | fixupKills (MachineBasicBlock &MBB) |
Fixes register kill flags that scheduling has made invalid. More... | |
Public Member Functions inherited from llvm::ScheduleDAG | |
ScheduleDAG (MachineFunction &mf) | |
virtual | ~ScheduleDAG () |
void | clearDAG () |
Clears the DAG state (between regions). More... | |
const MCInstrDesc * | getInstrDesc (const SUnit *SU) const |
Returns the MCInstrDesc of this SUnit. More... | |
void | dumpNodeName (const SUnit &SU) const |
virtual void | addCustomGraphFeatures (GraphWriter< ScheduleDAG *> &) const |
Adds custom features for a visualization of the ScheduleDAG. More... | |
unsigned | VerifyScheduledDAG (bool isBottomUp) |
Verifies that all SUnits were scheduled and that their state is consistent. More... | |
Protected Member Functions | |
void | postprocessDAG () |
Apply each ScheduleDAGMutation step in order. More... | |
void | initQueues (ArrayRef< SUnit *> TopRoots, ArrayRef< SUnit *> BotRoots) |
Release ExitSU predecessors and setup scheduler queues. More... | |
void | updateQueues (SUnit *SU, bool IsTopNode) |
Update scheduler DAG and queues after scheduling an instruction. More... | |
void | placeDebugValues () |
Reinsert debug_values recorded in ScheduleDAGInstrs::DbgValues. More... | |
void | dumpSchedule () const |
dump the scheduled Sequence. More... | |
bool | checkSchedLimit () |
void | findRootsAndBiasEdges (SmallVectorImpl< SUnit *> &TopRoots, SmallVectorImpl< SUnit *> &BotRoots) |
void | releaseSucc (SUnit *SU, SDep *SuccEdge) |
ReleaseSucc - Decrement the NumPredsLeft count of a successor. More... | |
void | releaseSuccessors (SUnit *SU) |
releaseSuccessors - Call releaseSucc on each of SU's successors. More... | |
void | releasePred (SUnit *SU, SDep *PredEdge) |
ReleasePred - Decrement the NumSuccsLeft count of a predecessor. More... | |
void | releasePredecessors (SUnit *SU) |
releasePredecessors - Call releasePred on each of SU's predecessors. More... | |
Protected Member Functions inherited from llvm::ScheduleDAGInstrs | |
void | reduceHugeMemNodeMaps (Value2SUsMap &stores, Value2SUsMap &loads, unsigned N) |
Reduces maps in FIFO order, by N SUs. More... | |
void | addChainDependency (SUnit *SUa, SUnit *SUb, unsigned Latency=0) |
Adds a chain edge between SUa and SUb, but only if both AliasAnalysis and Target fail to deny the dependency. More... | |
void | addChainDependencies (SUnit *SU, SUList &SUs, unsigned Latency) |
Adds dependencies as needed from all SUs in list to SU. More... | |
void | addChainDependencies (SUnit *SU, Value2SUsMap &Val2SUsMap) |
Adds dependencies as needed from all SUs in map, to SU. More... | |
void | addChainDependencies (SUnit *SU, Value2SUsMap &Val2SUsMap, ValueType V) |
Adds dependencies as needed to SU, from all SUs mapped to V. More... | |
void | addBarrierChain (Value2SUsMap &map) |
Adds barrier chain edges from all SUs in map, and then clear the map. More... | |
void | insertBarrierChain (Value2SUsMap &map) |
Inserts a barrier chain in a huge region, far below current SU. More... | |
void | initSUnits () |
Creates an SUnit for each real instruction, numbered in top-down topological order. More... | |
void | addPhysRegDataDeps (SUnit *SU, unsigned OperIdx) |
MO is an operand of SU's instruction that defines a physical register. More... | |
void | addPhysRegDeps (SUnit *SU, unsigned OperIdx) |
Adds register dependencies (data, anti, and output) from this SUnit to following instructions in the same scheduling region that depend the physical register referenced at OperIdx. More... | |
void | addVRegDefDeps (SUnit *SU, unsigned OperIdx) |
Adds register output and data dependencies from this SUnit to instructions that occur later in the same scheduling region if they read from or write to the virtual register defined at OperIdx. More... | |
void | addVRegUseDeps (SUnit *SU, unsigned OperIdx) |
Adds a register data dependency if the instruction that defines the virtual register used at OperIdx is mapped to an SUnit. More... | |
void | startBlockForKills (MachineBasicBlock *BB) |
Initializes register live-range state for updating kills. More... | |
void | toggleKillFlag (MachineInstr &MI, MachineOperand &MO) |
Toggles a register operand kill flag. More... | |
LaneBitmask | getLaneMaskForMO (const MachineOperand &MO) const |
Returns a mask for which lanes get read/written by the given (register) machine operand. More... | |
Protected Member Functions inherited from llvm::ScheduleDAG | |
void | dumpNodeAll (const SUnit &SU) const |
Protected Attributes | |
AliasAnalysis * | AA |
LiveIntervals * | LIS |
std::unique_ptr< MachineSchedStrategy > | SchedImpl |
ScheduleDAGTopologicalSort | Topo |
Topo - A topological ordering for SUnits which permits fast IsReachable and similar queries. More... | |
std::vector< std::unique_ptr< ScheduleDAGMutation > > | Mutations |
Ordered list of DAG postprocessing steps. More... | |
MachineBasicBlock::iterator | CurrentTop |
The top of the unscheduled zone. More... | |
MachineBasicBlock::iterator | CurrentBottom |
The bottom of the unscheduled zone. More... | |
const SUnit * | NextClusterPred = nullptr |
Record the next node in a scheduled cluster. More... | |
const SUnit * | NextClusterSucc = nullptr |
unsigned | NumInstrsScheduled = 0 |
The number of instructions scheduled so far. More... | |
Protected Attributes inherited from llvm::ScheduleDAGInstrs | |
const MachineLoopInfo * | MLI |
const MachineFrameInfo & | MFI |
TargetSchedModel | SchedModel |
TargetSchedModel provides an interface to the machine model. More... | |
bool | RemoveKillFlags |
True if the DAG builder should remove kill flags (in preparation for rescheduling). More... | |
bool | CanHandleTerminators = false |
The standard DAG builder does not normally include terminators as DAG nodes because it does not create the necessary dependencies to prevent reordering. More... | |
bool | TrackLaneMasks = false |
Whether lane masks should get tracked. More... | |
MachineBasicBlock * | BB |
The block in which to insert instructions. More... | |
MachineBasicBlock::iterator | RegionBegin |
The beginning of the range to be scheduled. More... | |
MachineBasicBlock::iterator | RegionEnd |
The end of the range to be scheduled. More... | |
unsigned | NumRegionInstrs |
Instructions in this region (distance(RegionBegin, RegionEnd)). More... | |
DenseMap< MachineInstr *, SUnit * > | MISUnitMap |
After calling BuildSchedGraph, each machine instruction in the current scheduling region is mapped to an SUnit. More... | |
Reg2SUnitsMap | Defs |
Defs, Uses - Remember where defs and uses of each register are as we iterate upward through the instructions. More... | |
Reg2SUnitsMap | Uses |
VReg2SUnitMultiMap | CurrentVRegDefs |
Tracks the last instruction(s) in this region defining each virtual register. More... | |
VReg2SUnitOperIdxMultiMap | CurrentVRegUses |
Tracks the last instructions in this region using each virtual register. More... | |
AliasAnalysis * | AAForDep = nullptr |
SUnit * | BarrierChain = nullptr |
Remember a generic side-effecting instruction as we proceed. More... | |
UndefValue * | UnknownValue |
For an unanalyzable memory access, this Value is used in maps. More... | |
DbgValueVector | DbgValues |
Remember instruction that precedes DBG_VALUE. More... | |
MachineInstr * | FirstDbgValue = nullptr |
LivePhysRegs | LiveRegs |
Set of live physical registers for updating kill flags. More... | |
Additional Inherited Members | |
Public Types inherited from llvm::ScheduleDAGInstrs | |
using | SUList = std::list< SUnit * > |
A list of SUnits, used in Value2SUsMap, during DAG construction. More... | |
Public Attributes inherited from llvm::ScheduleDAG | |
const LLVMTargetMachine & | TM |
Target processor. More... | |
const TargetInstrInfo * | TII |
Target instruction information. More... | |
const TargetRegisterInfo * | TRI |
Target processor register info. More... | |
MachineFunction & | MF |
Machine function. More... | |
MachineRegisterInfo & | MRI |
Virtual/real register map. More... | |
std::vector< SUnit > | SUnits |
The scheduling units. More... | |
SUnit | EntrySU |
Special node for the region entry. More... | |
SUnit | ExitSU |
Special node for the region exit. More... | |
bool | StressSched |
Protected Types inherited from llvm::ScheduleDAGInstrs | |
using | DbgValueVector = std::vector< std::pair< MachineInstr *, MachineInstr * > > |
ScheduleDAGMI is an implementation of ScheduleDAGInstrs that simply schedules machine instructions according to the given MachineSchedStrategy without much extra book-keeping.
This is the common functionality between PreRA and PostRA MachineScheduler.
Definition at line 262 of file MachineScheduler.h.
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Definition at line 292 of file MachineScheduler.h.
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Referenced by llvm::ReadyQueue::dump().
Add a DAG edge to the given SU with the given predecessor dependence data.
Definition at line 612 of file MachineScheduler.cpp.
References llvm::SUnit::addPred(), llvm::SDep::getSUnit(), and llvm::SDep::isArtificial().
Referenced by llvm::HexagonSubtarget::CallMutation::apply(), llvm::createCopyConstrainDAGMutation(), and fuseInstructionPair().
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Add a postprocessing step to the DAG builder.
Mutations are applied in the order that they are added after normal DAG building and before MachineSchedStrategy initialization.
ScheduleDAGMI takes ownership of the Mutation object.
Definition at line 318 of file MachineScheduler.h.
References addEdge().
Referenced by llvm::AArch64beTargetMachine::AArch64beTargetMachine(), llvm::ARMBETargetMachine::ARMBETargetMachine(), createGCNMaxOccupancyMachineScheduler(), llvm::createGenericSchedLive(), createVLIWMachineSched(), llvm::X86TargetMachine::getTargetTransformInfo(), and llvm::GCNTargetMachine::getTargetTransformInfo().
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Definition at line 335 of file MachineScheduler.h.
References llvm::sys::path::begin(), llvm::sys::path::end(), and MI.
Referenced by llvm::GCNMaxOccupancySchedStrategy::pickNode(), llvm::GenericScheduler::pickNode(), and llvm::PostGenericScheduler::pickNode().
True if an edge can be added from PredSU to SuccSU without creating a cycle.
Definition at line 608 of file MachineScheduler.cpp.
Referenced by llvm::createCopyConstrainDAGMutation().
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Definition at line 743 of file MachineScheduler.cpp.
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If this method returns true, handling of the scheduling regions themselves (in case of a scheduling boundary in MBB) will be done beginning with the topmost region of MBB.
Reimplemented from llvm::ScheduleDAGInstrs.
Definition at line 303 of file MachineScheduler.h.
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dump the scheduled Sequence.
Definition at line 923 of file MachineScheduler.cpp.
References llvm::sys::path::begin(), llvm::dbgs(), llvm::sys::path::end(), and MI.
Referenced by llvm::SIScheduleDAGMI::schedule().
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overridevirtual |
Implement the ScheduleDAGInstrs interface for handling the next scheduling region.
enterRegion - Called back from MachineScheduler::runOnMachineFunction after crossing a scheduling boundary.
This covers all instructions in a block, while schedule() may only cover a subset.
[begin, end) includes all instructions in the region, including the boundary itself and single-instruction regions that don't get scheduled.
Reimplemented from llvm::ScheduleDAGInstrs.
Reimplemented in llvm::ScheduleDAGMILive, and llvm::GCNIterativeScheduler.
Definition at line 713 of file MachineScheduler.cpp.
References llvm::ScheduleDAGInstrs::enterRegion().
Referenced by llvm::ScheduleDAGMILive::enterRegion().
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Definition at line 840 of file MachineScheduler.cpp.
References assert(), and llvm::SmallVectorTemplateBase< T >::push_back().
Referenced by llvm::GCNIterativeScheduler::BuildDAG::BuildDAG(), postprocessDAG(), and llvm::SIScheduleDAGMI::schedule().
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Cleans up after scheduling in the given block.
Reimplemented from llvm::ScheduleDAGInstrs.
Definition at line 704 of file MachineScheduler.cpp.
References llvm::ScheduleDAGInstrs::finishBlock().
Referenced by llvm::GCNScheduleDAGMILive::finalizeSchedule().
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Definition at line 308 of file MachineScheduler.h.
References llvm::MachineSchedContext::LIS.
Referenced by llvm::createCopyConstrainDAGMutation().
Definition at line 356 of file MachineScheduler.h.
Referenced by llvm::GenericScheduler::tryCandidate().
Definition at line 358 of file MachineScheduler.h.
References Name.
Referenced by llvm::GenericScheduler::tryCandidate(), and llvm::PostGenericScheduler::tryCandidate().
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Return true if this DAG supports VReg liveness and RegPressure.
Reimplemented in llvm::ScheduleDAGMILive.
Definition at line 311 of file MachineScheduler.h.
Referenced by llvm::createCopyConstrainDAGMutation(), llvm::createGenericSchedPostRA(), llvm::DOTGraphTraits< ScheduleDAGMI * >::getNodeAttributes(), llvm::DOTGraphTraits< ScheduleDAGMI * >::getNodeLabel(), llvm::R600SchedStrategy::initialize(), and llvm::GenericScheduler::initialize().
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Release ExitSU predecessors and setup scheduler queues.
Identify DAG roots and setup scheduler queues.
Definition at line 859 of file MachineScheduler.cpp.
References E, I, nextIfDebug(), llvm::ArrayRef< T >::rbegin(), and llvm::ArrayRef< T >::rend().
Referenced by llvm::ScheduleDAGMILive::initQueues().
void ScheduleDAGMI::moveInstruction | ( | MachineInstr * | MI, |
MachineBasicBlock::iterator | InsertPos | ||
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Change the position of an instruction within the basic block and update live ranges and region boundary iterators.
This is normally called from the main scheduler loop but may also be invoked by the scheduling strategy to perform additional code motion.
Definition at line 725 of file MachineScheduler.cpp.
References MI.
Referenced by llvm::GenericScheduler::reschedulePhysReg().
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Reinsert debug_values recorded in ScheduleDAGInstrs::DbgValues.
Reinsert any remaining debug_values, just like the PostRA scheduler.
Definition at line 900 of file MachineScheduler.cpp.
References P.
Referenced by llvm::GCNScheduleDAGMILive::schedule(), llvm::SIScheduleDAGMI::schedule(), and llvm::GCNIterativeScheduler::scheduleRegion().
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Apply each ScheduleDAGMutation step in order.
This allows different instances of ScheduleDAGMI to perform custom DAG postprocessing.
Definition at line 834 of file MachineScheduler.cpp.
References findRootsAndBiasEdges().
ReleasePred - Decrement the NumSuccsLeft count of a predecessor.
When NumSuccsLeft reaches zero, release the predecessor node.
FIXME: Adjust PredSU height based on MinLatency.
Definition at line 666 of file MachineScheduler.cpp.
References llvm::SUnit::BotReadyCycle, llvm::dbgs(), llvm::SDep::getLatency(), llvm::SDep::getSUnit(), llvm::SDep::isCluster(), llvm::SDep::isWeak(), llvm_unreachable, llvm::SUnit::NumSuccsLeft, and llvm::SUnit::WeakSuccsLeft.
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releasePredecessors - Call releasePred on each of SU's predecessors.
Definition at line 694 of file MachineScheduler.cpp.
References llvm::SUnit::Preds.
ReleaseSucc - Decrement the NumPredsLeft count of a successor.
When NumPredsLeft reaches zero, release the successor node.
FIXME: Adjust SuccSU height based on MinLatency.
Definition at line 629 of file MachineScheduler.cpp.
References llvm::dbgs(), llvm::SDep::getLatency(), llvm::SDep::getSUnit(), llvm::SDep::isCluster(), llvm::SDep::isWeak(), llvm_unreachable, llvm::SUnit::NumPredsLeft, llvm::SUnit::TopReadyCycle, and llvm::SUnit::WeakPredsLeft.
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releaseSuccessors - Call releaseSucc on each of SU's successors.
Definition at line 657 of file MachineScheduler.cpp.
References llvm::SUnit::Succs.
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Implement ScheduleDAGInstrs interface for scheduling a sequence of reorderable instructions.
Per-region scheduling driver, called back from MachineScheduler::runOnMachineFunction.
This is a simplified driver that does not consider liveness or register pressure. It is useful for PostRA scheduling and potentially other custom schedulers.
Implements llvm::ScheduleDAGInstrs.
Reimplemented in llvm::ScheduleDAGMILive, llvm::SIScheduleDAGMI, llvm::GCNScheduleDAGMILive, llvm::VLIWMachineScheduler, and llvm::GCNIterativeScheduler.
Definition at line 758 of file MachineScheduler.cpp.
References assert(), llvm::sys::path::begin(), llvm::dbgs(), llvm::dump(), llvm::SUnit::getInstr(), getParent(), llvm::SUnit::isBottomReady(), llvm::SUnit::isScheduled, llvm::SUnit::isTopReady(), LLVM_DEBUG, MI, nextIfDebug(), llvm::printMBBReference(), and priorNonDebug().
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Prepares to perform scheduling in the given block.
Reimplemented from llvm::ScheduleDAGInstrs.
Definition at line 699 of file MachineScheduler.cpp.
References llvm::ScheduleDAGInstrs::startBlock().
Referenced by llvm::GCNScheduleDAGMILive::finalizeSchedule().
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Definition at line 334 of file MachineScheduler.h.
Referenced by llvm::GCNMaxOccupancySchedStrategy::pickNode(), llvm::GenericScheduler::pickNode(), and llvm::PostGenericScheduler::pickNode().
Update scheduler DAG and queues after scheduling an instruction.
Update scheduler queues after scheduling an instruction.
Definition at line 889 of file MachineScheduler.cpp.
References llvm::SUnit::isScheduled.
viewGraph - Pop up a ghostview window with the reachable parts of the DAG rendered using 'dot'.
Reimplemented from llvm::ScheduleDAG.
Definition at line 3717 of file MachineScheduler.cpp.
References llvm::errs(), and ViewGraph().
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Out-of-line implementation with no arguments is handy for gdb.
Reimplemented from llvm::ScheduleDAG.
Definition at line 3727 of file MachineScheduler.cpp.
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Definition at line 264 of file MachineScheduler.h.
Referenced by llvm::GCNIterativeScheduler::BuildDAG::BuildDAG().
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The bottom of the unscheduled zone.
Definition at line 279 of file MachineScheduler.h.
Referenced by llvm::SIScheduleDAGMI::schedule().
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The top of the unscheduled zone.
Definition at line 276 of file MachineScheduler.h.
Referenced by llvm::SIScheduleDAGMI::schedule().
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Definition at line 265 of file MachineScheduler.h.
Referenced by llvm::GCNScheduleDAGMILive::finalizeSchedule(), llvm::GCNScheduleDAGMILive::schedule(), and llvm::GCNIterativeScheduler::OverrideLegacyStrategy::schedule().
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Ordered list of DAG postprocessing steps.
Definition at line 273 of file MachineScheduler.h.
Record the next node in a scheduled cluster.
Definition at line 282 of file MachineScheduler.h.
Definition at line 283 of file MachineScheduler.h.
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The number of instructions scheduled so far.
Used to cut off the scheduler at the point determined by misched-cutoff.
Definition at line 288 of file MachineScheduler.h.
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Definition at line 266 of file MachineScheduler.h.
Referenced by llvm::GCNScheduleDAGMILive::finalizeSchedule(), llvm::GCNIterativeScheduler::OverrideLegacyStrategy::OverrideLegacyStrategy(), llvm::GCNScheduleDAGMILive::schedule(), llvm::SIScheduleDAGMI::schedule(), and llvm::GCNIterativeScheduler::OverrideLegacyStrategy::~OverrideLegacyStrategy().
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Topo - A topological ordering for SUnits which permits fast IsReachable and similar queries.
Definition at line 270 of file MachineScheduler.h.
Referenced by llvm::GCNIterativeScheduler::BuildDAG::BuildDAG(), and llvm::SIScheduleDAGMI::SIScheduleDAGMI().