LLVM: lib/CodeGen/MachinePipeliner.cpp File Reference (original) (raw)

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Namespaces
namespace llvm
This is an optimization pass for GlobalISel generic memory operations.
Functions
STATISTIC (NumTrytoPipeline, "Number of loops that we attempt to pipeline")
STATISTIC (NumPipelined, "Number of loops software pipelined")
STATISTIC (NumNodeOrderIssues, "Number of node order issues found")
STATISTIC (NumFailBranch, "Pipeliner abort due to unknown branch")
STATISTIC (NumFailLoop, "Pipeliner abort due to unsupported loop")
STATISTIC (NumFailPreheader, "Pipeliner abort due to missing preheader")
STATISTIC (NumFailLargeMaxMII, "Pipeliner abort due to MaxMII too large")
STATISTIC (NumFailZeroMII, "Pipeliner abort due to zero MII")
STATISTIC (NumFailNoSchedule, "Pipeliner abort due to no schedule found")
STATISTIC (NumFailZeroStage, "Pipeliner abort due to zero stage")
STATISTIC (NumFailLargeMaxStage, "Pipeliner abort due to too many stages")
cl::opt< bool > llvm::SwpEnableCopyToPhi ("pipeliner-enable-copytophi", cl::ReallyHidden, cl::init(true), cl::desc("Enable CopyToPhi DAG Mutation"))
cl::opt< int > llvm::SwpForceIssueWidth ("pipeliner-force-issue-width", cl::desc("Force pipeliner to use specified issue width."), cl::Hidden, cl::init(-1))
A command line argument to force pipeliner to use specified issue width.
INITIALIZE_PASS_BEGIN (MachinePipeliner, DEBUG_TYPE, "Modulo Software Pipelining", false, false) INITIALIZE_PASS_END(MachinePipeliner
static void getPhiRegs (MachineInstr &Phi, MachineBasicBlock *Loop, unsigned &InitVal, unsigned &LoopVal)
Return the register values for the operands of a Phi instruction.
static unsigned getLoopPhiReg (const MachineInstr &Phi, const MachineBasicBlock *LoopBB)
Return the Phi register value that comes the loop block.
static bool isSuccOrder (SUnit *SUa, SUnit *SUb)
Return true if SUb can be reached from SUa following the chain edges.
static bool isDependenceBarrier (MachineInstr &MI)
Return true if the instruction causes a chain between memory references before and after it.
static void getUnderlyingObjects (const MachineInstr *MI, SmallVectorImpl< const Value * > &Objs)
Return the underlying objects for the memory references of an instruction.
static void computeScheduledInsts (const SwingSchedulerDAG *SSD, SMSchedule &Schedule, std::vector< MachineInstr * > &OrderedInsts, DenseMap< MachineInstr *, unsigned > &Stages)
Create an instruction stream that represents a single iteration and stage of each instruction.
static bool pred_L (SetVector< SUnit * > &NodeOrder, SmallSetVector< SUnit *, 8 > &Preds, SwingSchedulerDDG *DDG, const NodeSet *S=nullptr)
Compute the Pred_L(O) set, as defined in the paper.
static bool succ_L (SetVector< SUnit * > &NodeOrder, SmallSetVector< SUnit *, 8 > &Succs, SwingSchedulerDDG *DDG, const NodeSet *S=nullptr)
Compute the Succ_L(O) set, as defined in the paper.
static bool computePath (SUnit *Cur, SetVector< SUnit * > &Path, SetVector< SUnit * > &DestNodes, SetVector< SUnit * > &Exclude, SmallPtrSet< SUnit *, 8 > &Visited, SwingSchedulerDDG *DDG)
Return true if there is a path from the specified node to any of the nodes in DestNodes.
static void computeLiveOuts (MachineFunction &MF, RegPressureTracker &RPTracker, NodeSet &NS)
Compute the live-out registers for the instructions in a node-set.
static bool isIntersect (SmallSetVector< SUnit *, 8 > &Set1, const NodeSet &Set2, SmallSetVector< SUnit *, 8 > &Result)
Return true if Set1 contains elements in Set2.
static SUnit * multipleIterations (SUnit *SU, SwingSchedulerDAG *DAG)
If an instruction has a use that spans multiple iterations, then return true.
Variables
static cl::opt< bool > EnableSWP ("enable-pipeliner", cl::Hidden, cl::init(true), cl::desc("Enable Software Pipelining"))
A command line option to turn software pipelining on or off.
static cl::opt< bool > EnableSWPOptSize ("enable-pipeliner-opt-size", cl::desc("Enable SWP at Os."), cl::Hidden, cl::init(false))
A command line option to enable SWP at -Os.
static cl::opt< int > SwpMaxMii ("pipeliner-max-mii", cl::desc("Size limit for the MII."), cl::Hidden, cl::init(27))
A command line argument to limit minimum initial interval for pipelining.
static cl::opt< int > SwpForceII ("pipeliner-force-ii", cl::desc("Force pipeliner to use specified II."), cl::Hidden, cl::init(-1))
A command line argument to force pipeliner to use specified initial interval.
static cl::opt< int > SwpMaxStages ("pipeliner-max-stages", cl::desc("Maximum stages allowed in the generated scheduled."), cl::Hidden, cl::init(3))
A command line argument to limit the number of stages in the pipeline.
static cl::opt< bool > SwpPruneDeps ("pipeliner-prune-deps", cl::desc("Prune dependences between unrelated Phi nodes."), cl::Hidden, cl::init(true))
A command line option to disable the pruning of chain dependences due to an unrelated Phi.
static cl::opt< bool > SwpPruneLoopCarried ("pipeliner-prune-loop-carried", cl::desc("Prune loop carried order dependences."), cl::Hidden, cl::init(true))
A command line option to disable the pruning of loop carried order dependences.
static cl::opt< int > SwpLoopLimit ("pipeliner-max", cl::Hidden, cl::init(-1))
static cl::opt< bool > SwpIgnoreRecMII ("pipeliner-ignore-recmii", cl::ReallyHidden, cl::desc("Ignore RecMII"))
static cl::opt< bool > SwpShowResMask ("pipeliner-show-mask", cl::Hidden, cl::init(false))
static cl::opt< bool > SwpDebugResource ("pipeliner-dbg-res", cl::Hidden, cl::init(false))
static cl::opt< bool > EmitTestAnnotations ("pipeliner-annotate-for-testing", cl::Hidden, cl::init(false), cl::desc("Instead of emitting the pipelined code, annotate instructions " "with the generated schedule for feeding into the " "-modulo-schedule-test pass"))
static cl::opt< bool > ExperimentalCodeGen ("pipeliner-experimental-cg", cl::Hidden, cl::init(false), cl::desc("Use the experimental peeling code generator for software pipelining"))
static cl::opt< int > SwpIISearchRange ("pipeliner-ii-search-range", cl::desc("Range to search for II"), cl::Hidden, cl::init(10))
static cl::opt< bool > LimitRegPressure ("pipeliner-register-pressure", cl::Hidden, cl::init(false), cl::desc("Limit register pressure of scheduled loop"))
static cl::opt< int > RegPressureMargin ("pipeliner-register-pressure-margin", cl::Hidden, cl::init(5), cl::desc("Margin representing the unused percentage of " "the register pressure limit"))
static cl::opt< bool > MVECodeGen ("pipeliner-mve-cg", cl::Hidden, cl::init(false), cl::desc("Use the MVE code generator for software pipelining"))
cl::opt< WindowSchedulingFlag > llvm::WindowSchedulingOption ("window-sched", cl::Hidden, cl::init(WindowSchedulingFlag::WS_On), cl::desc("Set how to use window scheduling algorithm."), cl::values(clEnumValN(WindowSchedulingFlag::WS_Off, "off", "Turn off window algorithm."), clEnumValN(WindowSchedulingFlag::WS_On, "on", "Use window algorithm after SMS algorithm fails."), clEnumValN(WindowSchedulingFlag::WS_Force, "force", "Use window algorithm instead of SMS algorithm.")))
A command line argument to set the window scheduling option.
DEBUG_TYPE
Modulo Software Pipelining
Modulo Software false

DEBUG_TYPE

#define DEBUG_TYPE "pipeliner"

computeLiveOuts()

Compute the live-out registers for the instructions in a node-set.

The live-out registers are those that are defined in the node-set, but not used. Except for use operands of Phis.

Definition at line 1980 of file MachinePipeliner.cpp.

References llvm::RegPressureTracker::addLiveRegs(), llvm::MachineInstr::all_defs(), llvm::SUnit::getInstr(), llvm::LaneBitmask::getNone(), llvm::MachineFunction::getRegInfo(), llvm::TargetSubtargetInfo::getRegisterInfo(), llvm::MachineFunction::getSubtarget(), MI, MRI, llvm::SmallVectorTemplateBase< T, bool >::push_back(), TRI, and Uses.

computePath()

computeScheduledInsts()

Create an instruction stream that represents a single iteration and stage of each instruction.

This function differs from SMSchedule::finalizeSchedule in that this doesn't have any side-effect to SwingSchedulerDAG. That is, this function is an approximation of SMSchedule::finalizeSchedule with all non-const operations removed.

Definition at line 1081 of file MachinePipeliner.cpp.

References llvm::SMSchedule::getFinalCycle(), llvm::SMSchedule::getFirstCycle(), llvm::SMSchedule::getInitiationInterval(), llvm::SUnit::getInstr(), llvm::SMSchedule::getInstructions(), llvm::SMSchedule::getMaxStageCount(), MI, llvm::SMSchedule::reorderInstructions(), llvm::reverse(), and llvm::SMSchedule::stageScheduled().

getLoopPhiReg()

getPhiRegs()

getUnderlyingObjects()

INITIALIZE_PASS_BEGIN()

isDependenceBarrier()

Return true if the instruction causes a chain between memory references before and after it.

Definition at line 806 of file MachinePipeliner.cpp.

References MI.

isIntersect()

isSuccOrder()

multipleIterations()

pred_L()

Compute the Pred_L(O) set, as defined in the paper.

The set is defined as the predecessors of the elements of NodeOrder that are not also in NodeOrder.

Definition at line 1879 of file MachinePipeliner.cpp.

References llvm::SetVector< T, Vector, Set, N >::clear(), llvm::SetVector< T, Vector, Set, N >::empty(), llvm::SwingSchedulerDDG::getInEdges(), llvm::SwingSchedulerDDG::getOutEdges(), llvm::SetVector< T, Vector, Set, N >::insert(), and llvm::NodeOrder.

STATISTIC() [1/11]

STATISTIC ( NumFailBranch ,
"Pipeliner abort due to unknown branch"
)

STATISTIC() [2/11]

STATISTIC ( NumFailLargeMaxMII ,
"Pipeliner abort due to MaxMII too large"
)

STATISTIC() [3/11]

STATISTIC ( NumFailLargeMaxStage ,
"Pipeliner abort due to too many stages"
)

STATISTIC() [4/11]

STATISTIC ( NumFailLoop ,
"Pipeliner abort due to unsupported loop"
)

STATISTIC() [5/11]

STATISTIC ( NumFailNoSchedule ,
"Pipeliner abort due to no schedule found"
)

STATISTIC() [6/11]

STATISTIC ( NumFailPreheader ,
"Pipeliner abort due to missing preheader"
)

STATISTIC() [7/11]

STATISTIC ( NumFailZeroMII ,
"Pipeliner abort due to zero MII"
)

STATISTIC() [8/11]

STATISTIC ( NumFailZeroStage ,
"Pipeliner abort due to zero stage"
)

STATISTIC() [9/11]

STATISTIC ( NumNodeOrderIssues ,
"Number of node order issues found"
)

STATISTIC() [10/11]

STATISTIC ( NumPipelined ,
"Number of loops software pipelined"
)

STATISTIC() [11/11]

STATISTIC ( NumTrytoPipeline ,
"Number of loops that we attempt to pipeline"
)

succ_L()

Compute the Succ_L(O) set, as defined in the paper.

The set is defined as the successors of the elements of NodeOrder that are not also in NodeOrder.

Definition at line 1915 of file MachinePipeliner.cpp.

References llvm::SetVector< T, Vector, Set, N >::clear(), llvm::SetVector< T, Vector, Set, N >::empty(), llvm::SwingSchedulerDDG::getInEdges(), llvm::SwingSchedulerDDG::getOutEdges(), llvm::SetVector< T, Vector, Set, N >::insert(), and llvm::NodeOrder.

DEBUG_TYPE

EmitTestAnnotations

cl::opt< bool > EmitTestAnnotations("pipeliner-annotate-for-testing", cl::Hidden, cl::init(false), cl::desc("Instead of emitting the pipelined code, annotate instructions " "with the generated schedule for feeding into the " "-modulo-schedule-test pass")) ( "pipeliner-annotate-for-testing" , cl::Hidden , cl::init(false) , cl::desc("Instead of emitting the pipelined code, annotate instructions " "with the generated schedule for feeding into the " "-modulo-schedule-test pass") ) static

EnableSWP

cl::opt< bool > EnableSWP("enable-pipeliner", cl::Hidden, cl::init(true), cl::desc("Enable Software Pipelining")) ( "enable-pipeliner" , cl::Hidden , cl::init(true) , cl::desc("Enable Software Pipelining") ) static

EnableSWPOptSize

cl::opt< bool > EnableSWPOptSize("enable-pipeliner-opt-size", cl::desc("Enable SWP at Os."), cl::Hidden, cl::init(false)) ( "enable-pipeliner-opt-size" , cl::desc("Enable SWP at Os.") , cl::Hidden , cl::init(false) ) static

ExperimentalCodeGen

cl::opt< bool > ExperimentalCodeGen("pipeliner-experimental-cg", cl::Hidden, cl::init(false), cl::desc( "Use the experimental peeling code generator for software pipelining")) ( "pipeliner-experimental-cg" , cl::Hidden , cl::init(false) , cl::desc( "Use the experimental peeling code generator for software pipelining") ) static

false

LimitRegPressure

cl::opt< bool > LimitRegPressure("pipeliner-register-pressure", cl::Hidden, cl::init(false), cl::desc("Limit register pressure of scheduled loop")) ( "pipeliner-register-pressure" , cl::Hidden , cl::init(false) , cl::desc("Limit register pressure of scheduled loop") ) static

MVECodeGen

cl::opt< bool > MVECodeGen("pipeliner-mve-cg", cl::Hidden, cl::init(false), cl::desc("Use the MVE code generator for software pipelining")) ( "pipeliner-mve-cg" , cl::Hidden , cl::init(false) , cl::desc("Use the MVE code generator for software pipelining") ) static

Pipelining

Modulo Software Pipelining

RegPressureMargin

cl::opt< int > RegPressureMargin("pipeliner-register-pressure-margin", cl::Hidden, cl::init(5), cl::desc("Margin representing the unused percentage of " "the register pressure limit")) ( "pipeliner-register-pressure-margin" , cl::Hidden , cl::init(5) , cl::desc("Margin representing the unused percentage of " "the register pressure limit") ) static

SwpDebugResource

cl::opt< bool > SwpDebugResource("pipeliner-dbg-res", cl::Hidden, cl::init(false)) ( "pipeliner-dbg-res" , cl::Hidden , cl::init(false) ) static

SwpForceII

cl::opt< int > SwpForceII("pipeliner-force-ii", cl::desc("Force pipeliner to use specified II."), cl::Hidden, cl::init(-1)) ( "pipeliner-force-ii" , cl::desc("Force pipeliner to use specified II.") , cl::Hidden , cl::init(-1) ) static

A command line argument to force pipeliner to use specified initial interval.

SwpIgnoreRecMII

cl::opt< bool > SwpIgnoreRecMII("pipeliner-ignore-recmii", cl::ReallyHidden, cl::desc("Ignore RecMII")) ( "pipeliner-ignore-recmii" , cl::ReallyHidden , cl::desc("Ignore RecMII") ) static

SwpIISearchRange

cl::opt< int > SwpIISearchRange("pipeliner-ii-search-range", cl::desc("Range to search for II"), cl::Hidden, cl::init(10)) ( "pipeliner-ii-search-range" , cl::desc("Range to search for II") , cl::Hidden , cl::init(10) ) static

SwpLoopLimit

cl::opt< int > SwpLoopLimit("pipeliner-max", cl::Hidden, cl::init(-1)) ( "pipeliner-max" , cl::Hidden , cl::init(-1) ) static

SwpMaxMii

cl::opt< int > SwpMaxMii("pipeliner-max-mii", cl::desc("Size limit for the MII."), cl::Hidden, cl::init(27)) ( "pipeliner-max-mii" , cl::desc("Size limit for the MII.") , cl::Hidden , cl::init(27) ) static

SwpMaxStages

cl::opt< int > SwpMaxStages("pipeliner-max-stages", cl::desc("Maximum stages allowed in the generated scheduled."), cl::Hidden, cl::init(3)) ( "pipeliner-max-stages" , cl::desc("Maximum stages allowed in the generated scheduled.") , cl::Hidden , cl::init(3) ) static

SwpPruneDeps

cl::opt< bool > SwpPruneDeps("pipeliner-prune-deps", cl::desc("Prune dependences between unrelated Phi nodes."), cl::Hidden, cl::init(true)) ( "pipeliner-prune-deps" , cl::desc("Prune dependences between unrelated Phi nodes.") , cl::Hidden , cl::init(true) ) static

A command line option to disable the pruning of chain dependences due to an unrelated Phi.

SwpPruneLoopCarried

cl::opt< bool > SwpPruneLoopCarried("pipeliner-prune-loop-carried", cl::desc("Prune loop carried order dependences."), cl::Hidden, cl::init(true)) ( "pipeliner-prune-loop-carried" , cl::desc("Prune loop carried order dependences.") , cl::Hidden , cl::init(true) ) static

SwpShowResMask

cl::opt< bool > SwpShowResMask("pipeliner-show-mask", cl::Hidden, cl::init(false)) ( "pipeliner-show-mask" , cl::Hidden , cl::init(false) ) static