LLVM  8.0.1
Public Member Functions | Protected Member Functions | Protected Attributes | List of all members
llvm::ScheduleDAGMILive Class Reference

ScheduleDAGMILive is an implementation of ScheduleDAGInstrs that schedules machine instructions while updating LiveIntervals and tracking regpressure. More...

#include "llvm/CodeGen/MachineScheduler.h"

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Public Member Functions

 ScheduleDAGMILive (MachineSchedContext *C, std::unique_ptr< MachineSchedStrategy > S)
 
 ~ScheduleDAGMILive () override
 
bool hasVRegLiveness () const override
 Return true if this DAG supports VReg liveness and RegPressure. More...
 
bool isTrackingPressure () const
 Return true if register pressure tracking is enabled. More...
 
const IntervalPressuregetTopPressure () const
 Get current register pressure for the top scheduled instructions. More...
 
const RegPressureTrackergetTopRPTracker () const
 
const IntervalPressuregetBotPressure () const
 Get current register pressure for the bottom scheduled instructions. More...
 
const RegPressureTrackergetBotRPTracker () const
 
const IntervalPressuregetRegPressure () const
 Get register pressure for the entire scheduling region before scheduling. More...
 
const std::vector< PressureChange > & getRegionCriticalPSets () const
 
PressureDiffgetPressureDiff (const SUnit *SU)
 
const PressureDiffgetPressureDiff (const SUnit *SU) const
 
void computeDFSResult ()
 Compute a DFSResult after DAG building is complete, and before any queue comparisons. More...
 
const SchedDFSResultgetDFSResult () const
 Return a non-null DFS result if the scheduling strategy initialized it. More...
 
BitVectorgetScheduledTrees ()
 
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...
 
unsigned computeCyclicCriticalPath ()
 Compute the cyclic critical path through the DAG. More...
 
void dump () const override
 
- Public Member Functions inherited from llvm::ScheduleDAGMI
 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...
 
LiveIntervalsgetLIS () const
 
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 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 SUnitgetNextClusterPred () const
 
const SUnitgetNextClusterSucc () 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 TargetSchedModelgetSchedModel () const
 Gets the machine model for instruction scheduling. More...
 
const MCSchedClassDescgetSchedClass (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...
 
SUnitnewSUnit (MachineInstr *MI)
 Creates a new SUnit and return a ptr to it. More...
 
SUnitgetSUnit (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 MCInstrDescgetInstrDesc (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 buildDAGWithRegPressure ()
 Call ScheduleDAGInstrs::buildSchedGraph with register pressure tracking enabled. More...
 
void initQueues (ArrayRef< SUnit *> TopRoots, ArrayRef< SUnit *> BotRoots)
 Release ExitSU predecessors and setup scheduler queues. More...
 
void scheduleMI (SUnit *SU, bool IsTopNode)
 Move an instruction and update register pressure. More...
 
void initRegPressure ()
 
void updatePressureDiffs (ArrayRef< RegisterMaskPair > LiveUses)
 Update the PressureDiff array for liveness after scheduling this instruction. More...
 
void updateScheduledPressure (const SUnit *SU, const std::vector< unsigned > &NewMaxPressure)
 
void collectVRegUses (SUnit &SU)
 
- Protected Member Functions inherited from llvm::ScheduleDAGMI
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

RegisterClassInfoRegClassInfo
 
SchedDFSResultDFSResult = nullptr
 Information about DAG subtrees. More...
 
BitVector ScheduledTrees
 
MachineBasicBlock::iterator LiveRegionEnd
 
VReg2SUnitMultiMap VRegUses
 Maps vregs to the SUnits of their uses in the current scheduling region. More...
 
PressureDiffs SUPressureDiffs
 
bool ShouldTrackPressure = false
 Register pressure in this region computed by initRegPressure. More...
 
bool ShouldTrackLaneMasks = false
 
IntervalPressure RegPressure
 
RegPressureTracker RPTracker
 
std::vector< PressureChangeRegionCriticalPSets
 List of pressure sets that exceed the target's pressure limit before scheduling, listed in increasing set ID order. More...
 
IntervalPressure TopPressure
 The top of the unscheduled zone. More...
 
RegPressureTracker TopRPTracker
 
IntervalPressure BotPressure
 The bottom of the unscheduled zone. More...
 
RegPressureTracker BotRPTracker
 
bool DisconnectedComponentsRenamed = false
 True if disconnected subregister components are already renamed. More...
 
- Protected Attributes inherited from llvm::ScheduleDAGMI
AliasAnalysisAA
 
LiveIntervalsLIS
 
std::unique_ptr< MachineSchedStrategySchedImpl
 
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 SUnitNextClusterPred = nullptr
 Record the next node in a scheduled cluster. More...
 
const SUnitNextClusterSucc = nullptr
 
unsigned NumInstrsScheduled = 0
 The number of instructions scheduled so far. More...
 
- Protected Attributes inherited from llvm::ScheduleDAGInstrs
const MachineLoopInfoMLI
 
const MachineFrameInfoMFI
 
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...
 
MachineBasicBlockBB
 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...
 
AliasAnalysisAAForDep = nullptr
 
SUnitBarrierChain = nullptr
 Remember a generic side-effecting instruction as we proceed. More...
 
UndefValueUnknownValue
 For an unanalyzable memory access, this Value is used in maps. More...
 
DbgValueVector DbgValues
 Remember instruction that precedes DBG_VALUE. More...
 
MachineInstrFirstDbgValue = 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 LLVMTargetMachineTM
 Target processor. More...
 
const TargetInstrInfoTII
 Target instruction information. More...
 
const TargetRegisterInfoTRI
 Target processor register info. More...
 
MachineFunctionMF
 Machine function. More...
 
MachineRegisterInfoMRI
 Virtual/real register map. More...
 
std::vector< SUnitSUnits
 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 * > >
 

Detailed Description

ScheduleDAGMILive is an implementation of ScheduleDAGInstrs that schedules machine instructions while updating LiveIntervals and tracking regpressure.

Definition at line 396 of file MachineScheduler.h.

Constructor & Destructor Documentation

◆ ScheduleDAGMILive()

llvm::ScheduleDAGMILive::ScheduleDAGMILive ( MachineSchedContext C,
std::unique_ptr< MachineSchedStrategy S 
)
inline

Definition at line 439 of file MachineScheduler.h.

◆ ~ScheduleDAGMILive()

ScheduleDAGMILive::~ScheduleDAGMILive ( )
override

Definition at line 938 of file MachineScheduler.cpp.

Member Function Documentation

◆ buildDAGWithRegPressure()

void ScheduleDAGMILive::buildDAGWithRegPressure ( )
protected

Call ScheduleDAGInstrs::buildSchedGraph with register pressure tracking enabled.

Build the DAG and setup three register pressure trackers.

This sets up three trackers. RPTracker will cover the entire DAG region, TopTracker and BottomTracker will be initialized to the top and bottom of the DAG region without covereing any unscheduled instruction.

Definition at line 1272 of file MachineScheduler.cpp.

Referenced by llvm::SIScheduleDAGMI::schedule().

◆ collectVRegUses()

void ScheduleDAGMILive::collectVRegUses ( SUnit SU)
protected

◆ computeCyclicCriticalPath()

unsigned ScheduleDAGMILive::computeCyclicCriticalPath ( )

Compute the cyclic critical path through the DAG.

Compute the max cyclic critical path through the DAG.

The scheduling DAG only provides the critical path for single block loops. To handle loops that span blocks, we could use the vreg path latencies provided by MachineTraceMetrics instead. However, MachineTraceMetrics is not currently available for use in the scheduler.

The cyclic path estimation identifies a def-use pair that crosses the back edge and considers the depth and height of the nodes. For example, consider the following instruction sequence where each instruction has unit latency and defines an epomymous virtual register:

a->b(a,c)->c(b)->d(c)->exit

The cyclic critical path is a two cycles: b->c->b The acyclic critical path is four cycles: a->b->c->d->exit LiveOutHeight = height(c) = len(c->d->exit) = 2 LiveOutDepth = depth(c) + 1 = len(a->b->c) + 1 = 3 LiveInHeight = height(b) + 1 = len(b->c->d->exit) + 1 = 4 LiveInDepth = depth(b) = len(a->b) = 1

LiveOutDepth - LiveInDepth = 3 - 1 = 2 LiveInHeight - LiveOutHeight = 4 - 2 = 2 CyclicCriticalPath = min(2, 2) = 2

This could be relevant to PostRA scheduling, but is currently implemented assuming LiveIntervals.

Definition at line 1331 of file MachineScheduler.cpp.

References llvm::dbgs(), llvm::VNInfo::def, DefMI, llvm::SUnit::getDepth(), llvm::SUnit::getHeight(), llvm::SUnit::getInstr(), llvm::LiveRange::getVNInfoBefore(), llvm::VNInfo::isPHIDef(), llvm::SUnit::Latency, LLVM_DEBUG, llvm::make_range(), llvm::SUnit::NodeNum, P, llvm::LiveRange::Query(), Reg, TRI, and llvm::LiveQueryResult::valueIn().

Referenced by llvm::GenericScheduler::registerRoots().

◆ computeDFSResult()

void ScheduleDAGMILive::computeDFSResult ( )

Compute a DFSResult after DAG building is complete, and before any queue comparisons.

Definition at line 1295 of file MachineScheduler.cpp.

Referenced by llvm::createGenericSchedPostRA().

◆ dump()

void ScheduleDAGMILive::dump ( ) const
overridevirtual

Implements llvm::ScheduleDAG.

Definition at line 1177 of file MachineScheduler.cpp.

References llvm::dbgs(), and TRI.

Referenced by llvm::SIScheduleDAGMI::schedule().

◆ enterRegion()

void ScheduleDAGMILive::enterRegion ( MachineBasicBlock bb,
MachineBasicBlock::iterator  begin,
MachineBasicBlock::iterator  end,
unsigned  regioninstrs 
)
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::ScheduleDAGMI.

Reimplemented in llvm::GCNIterativeScheduler.

Definition at line 984 of file MachineScheduler.cpp.

References assert(), llvm::MachineBasicBlock::end(), and llvm::ScheduleDAGMI::enterRegion().

Referenced by llvm::GCNIterativeScheduler::enterRegion(), and llvm::GCNScheduleDAGMILive::finalizeSchedule().

◆ getBotPressure()

const IntervalPressure& llvm::ScheduleDAGMILive::getBotPressure ( ) const
inline

Get current register pressure for the bottom scheduled instructions.

Definition at line 458 of file MachineScheduler.h.

◆ getBotRPTracker()

const RegPressureTracker& llvm::ScheduleDAGMILive::getBotRPTracker ( ) const
inline

◆ getDFSResult()

const SchedDFSResult* llvm::ScheduleDAGMILive::getDFSResult ( ) const
inline

Return a non-null DFS result if the scheduling strategy initialized it.

Definition at line 480 of file MachineScheduler.h.

Referenced by llvm::createGenericSchedPostRA().

◆ getPressureDiff() [1/2]

PressureDiff& llvm::ScheduleDAGMILive::getPressureDiff ( const SUnit SU)
inline

Definition at line 468 of file MachineScheduler.h.

References llvm::SUnit::NodeNum.

Referenced by llvm::GenericScheduler::initCandidate().

◆ getPressureDiff() [2/2]

const PressureDiff& llvm::ScheduleDAGMILive::getPressureDiff ( const SUnit SU) const
inline

Definition at line 471 of file MachineScheduler.h.

References llvm::SUnit::NodeNum.

◆ getRegionCriticalPSets()

const std::vector<PressureChange>& llvm::ScheduleDAGMILive::getRegionCriticalPSets ( ) const
inline

Definition at line 464 of file MachineScheduler.h.

Referenced by llvm::GenericScheduler::initCandidate().

◆ getRegPressure()

const IntervalPressure& llvm::ScheduleDAGMILive::getRegPressure ( ) const
inline

Get register pressure for the entire scheduling region before scheduling.

Definition at line 462 of file MachineScheduler.h.

References llvm::Sched::RegPressure.

Referenced by llvm::GenericScheduler::initCandidate().

◆ getScheduledTrees()

BitVector& llvm::ScheduleDAGMILive::getScheduledTrees ( )
inline

◆ getTopPressure()

const IntervalPressure& llvm::ScheduleDAGMILive::getTopPressure ( ) const
inline

Get current register pressure for the top scheduled instructions.

Definition at line 454 of file MachineScheduler.h.

◆ getTopRPTracker()

const RegPressureTracker& llvm::ScheduleDAGMILive::getTopRPTracker ( ) const
inline

◆ hasVRegLiveness()

bool llvm::ScheduleDAGMILive::hasVRegLiveness ( ) const
inlineoverridevirtual

Return true if this DAG supports VReg liveness and RegPressure.

Reimplemented from llvm::ScheduleDAGMI.

Definition at line 448 of file MachineScheduler.h.

◆ initQueues()

void ScheduleDAGMILive::initQueues ( ArrayRef< SUnit *>  TopRoots,
ArrayRef< SUnit *>  BotRoots 
)
protected

Release ExitSU predecessors and setup scheduler queues.

Re-position the Top RP tracker in case the region beginning has changed.

Definition at line 1392 of file MachineScheduler.cpp.

References assert(), and llvm::ScheduleDAGMI::initQueues().

Referenced by llvm::SIScheduleDAGMI::schedule().

◆ initRegPressure()

void ScheduleDAGMILive::initRegPressure ( )
protected

◆ isTrackingPressure()

bool llvm::ScheduleDAGMILive::isTrackingPressure ( ) const
inline

Return true if register pressure tracking is enabled.

Definition at line 451 of file MachineScheduler.h.

Referenced by llvm::GenericScheduler::initCandidate(), and llvm::GenericScheduler::tryCandidate().

◆ schedule()

void ScheduleDAGMILive::schedule ( )
overridevirtual

Implement ScheduleDAGInstrs interface for scheduling a sequence of reorderable instructions.

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.

This is a skeletal driver, with all the functionality pushed into helpers, 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 to update any specialized state.

Reimplemented from llvm::ScheduleDAGMI.

Reimplemented in llvm::SIScheduleDAGMI, llvm::GCNScheduleDAGMILive, llvm::VLIWMachineScheduler, and llvm::GCNIterativeScheduler.

Definition at line 1210 of file MachineScheduler.cpp.

References assert(), llvm::sys::path::begin(), llvm::dbgs(), llvm::dump(), getParent(), llvm::SUnit::isScheduled, LLVM_DEBUG, and llvm::printMBBReference().

Referenced by llvm::GCNScheduleDAGMILive::schedule().

◆ scheduleMI()

void ScheduleDAGMILive::scheduleMI ( SUnit SU,
bool  IsTopNode 
)
protected

◆ updatePressureDiffs()

void ScheduleDAGMILive::updatePressureDiffs ( ArrayRef< RegisterMaskPair LiveUses)
protected

◆ updateScheduledPressure()

void ScheduleDAGMILive::updateScheduledPressure ( const SUnit SU,
const std::vector< unsigned > &  NewMaxPressure 
)
protected

Definition at line 1081 of file MachineScheduler.cpp.

References llvm::dbgs(), LLVM_DEBUG, llvm::max(), and TRI.

Referenced by initRegPressure().

Member Data Documentation

◆ BotPressure

IntervalPressure llvm::ScheduleDAGMILive::BotPressure
protected

The bottom of the unscheduled zone.

Definition at line 431 of file MachineScheduler.h.

◆ BotRPTracker

RegPressureTracker llvm::ScheduleDAGMILive::BotRPTracker
protected

Definition at line 432 of file MachineScheduler.h.

◆ DFSResult

SchedDFSResult* llvm::ScheduleDAGMILive::DFSResult = nullptr
protected

Information about DAG subtrees.

If DFSResult is NULL, then SchedulerTrees will be empty.

Definition at line 402 of file MachineScheduler.h.

◆ DisconnectedComponentsRenamed

bool llvm::ScheduleDAGMILive::DisconnectedComponentsRenamed = false
protected

True if disconnected subregister components are already renamed.

The renaming is only done on demand if lane masks are tracked.

Definition at line 436 of file MachineScheduler.h.

◆ LiveRegionEnd

MachineBasicBlock::iterator llvm::ScheduleDAGMILive::LiveRegionEnd
protected

Definition at line 405 of file MachineScheduler.h.

◆ RegClassInfo

RegisterClassInfo* llvm::ScheduleDAGMILive::RegClassInfo
protected

Definition at line 398 of file MachineScheduler.h.

◆ RegionCriticalPSets

std::vector<PressureChange> llvm::ScheduleDAGMILive::RegionCriticalPSets
protected

List of pressure sets that exceed the target's pressure limit before scheduling, listed in increasing set ID order.

Each pressure set is paired with its max pressure in the currently scheduled regions.

Definition at line 424 of file MachineScheduler.h.

◆ RegPressure

IntervalPressure llvm::ScheduleDAGMILive::RegPressure
protected

Definition at line 418 of file MachineScheduler.h.

◆ RPTracker

RegPressureTracker llvm::ScheduleDAGMILive::RPTracker
protected

◆ ScheduledTrees

BitVector llvm::ScheduleDAGMILive::ScheduledTrees
protected

Definition at line 403 of file MachineScheduler.h.

◆ ShouldTrackLaneMasks

bool llvm::ScheduleDAGMILive::ShouldTrackLaneMasks = false
protected

Definition at line 417 of file MachineScheduler.h.

Referenced by llvm::GCNScheduleDAGMILive::schedule().

◆ ShouldTrackPressure

bool llvm::ScheduleDAGMILive::ShouldTrackPressure = false
protected

Register pressure in this region computed by initRegPressure.

Definition at line 416 of file MachineScheduler.h.

◆ SUPressureDiffs

PressureDiffs llvm::ScheduleDAGMILive::SUPressureDiffs
protected

Definition at line 413 of file MachineScheduler.h.

◆ TopPressure

IntervalPressure llvm::ScheduleDAGMILive::TopPressure
protected

The top of the unscheduled zone.

Definition at line 427 of file MachineScheduler.h.

◆ TopRPTracker

RegPressureTracker llvm::ScheduleDAGMILive::TopRPTracker
protected

Definition at line 428 of file MachineScheduler.h.

Referenced by llvm::SIScheduleDAGMI::schedule().

◆ VRegUses

VReg2SUnitMultiMap llvm::ScheduleDAGMILive::VRegUses
protected

Maps vregs to the SUnits of their uses in the current scheduling region.

Definition at line 408 of file MachineScheduler.h.


The documentation for this class was generated from the following files: