LLVM 20.0.0git
Public Types | Public Member Functions | List of all members
llvm::ScheduleDAGTopologicalSort Class Reference

This class can compute a topological ordering for SUnits and provides methods for dynamically updating the ordering as new edges are added. More...

#include "llvm/CodeGen/ScheduleDAG.h"

Public Types

typedef std::vector< int >::iterator iterator
 
typedef std::vector< int >::const_iterator const_iterator
 
typedef std::vector< int >::reverse_iterator reverse_iterator
 
typedef std::vector< int >::const_reverse_iterator const_reverse_iterator
 

Public Member Functions

 ScheduleDAGTopologicalSort (std::vector< SUnit > &SUnits, SUnit *ExitSU)
 
void AddSUnitWithoutPredecessors (const SUnit *SU)
 Add a SUnit without predecessors to the end of the topological order.
 
void InitDAGTopologicalSorting ()
 Creates the initial topological ordering from the DAG to be scheduled.
 
std::vector< int > GetSubGraph (const SUnit &StartSU, const SUnit &TargetSU, bool &Success)
 Returns an array of SUs that are both in the successor subtree of StartSU and in the predecessor subtree of TargetSU.
 
bool IsReachable (const SUnit *SU, const SUnit *TargetSU)
 Checks if SU is reachable from TargetSU.
 
bool WillCreateCycle (SUnit *TargetSU, SUnit *SU)
 Returns true if addPred(TargetSU, SU) creates a cycle.
 
void AddPred (SUnit *Y, SUnit *X)
 Updates the topological ordering to accommodate an edge to be added from SUnit X to SUnit Y.
 
void AddPredQueued (SUnit *Y, SUnit *X)
 Queues an update to the topological ordering to accommodate an edge to be added from SUnit X to SUnit Y.
 
void RemovePred (SUnit *M, SUnit *N)
 Updates the topological ordering to accommodate an edge to be removed from the specified node N from the predecessors of the current node M.
 
void MarkDirty ()
 Mark the ordering as temporarily broken, after a new node has been added.
 
iterator begin ()
 
const_iterator begin () const
 
iterator end ()
 
const_iterator end () const
 
reverse_iterator rbegin ()
 
const_reverse_iterator rbegin () const
 
reverse_iterator rend ()
 
const_reverse_iterator rend () const
 

Detailed Description

This class can compute a topological ordering for SUnits and provides methods for dynamically updating the ordering as new edges are added.

This allows a very fast implementation of IsReachable, for example.

Definition at line 720 of file ScheduleDAG.h.

Member Typedef Documentation

◆ const_iterator

Definition at line 797 of file ScheduleDAG.h.

◆ const_reverse_iterator

typedef std::vector<int>::const_reverse_iterator llvm::ScheduleDAGTopologicalSort::const_reverse_iterator

Definition at line 804 of file ScheduleDAG.h.

◆ iterator

typedef std::vector<int>::iterator llvm::ScheduleDAGTopologicalSort::iterator

Definition at line 796 of file ScheduleDAG.h.

◆ reverse_iterator

typedef std::vector<int>::reverse_iterator llvm::ScheduleDAGTopologicalSort::reverse_iterator

Definition at line 803 of file ScheduleDAG.h.

Constructor & Destructor Documentation

◆ ScheduleDAGTopologicalSort()

ScheduleDAGTopologicalSort::ScheduleDAGTopologicalSort ( std::vector< SUnit > &  SUnits,
SUnit ExitSU 
)

Definition at line 751 of file ScheduleDAG.cpp.

Member Function Documentation

◆ AddPred()

void ScheduleDAGTopologicalSort::AddPred ( SUnit Y,
SUnit X 
)

Updates the topological ordering to accommodate an edge to be added from SUnit X to SUnit Y.

Definition at line 551 of file ScheduleDAG.cpp.

References assert(), llvm::BitVector::reset(), X, and Y.

◆ AddPredQueued()

void ScheduleDAGTopologicalSort::AddPredQueued ( SUnit Y,
SUnit X 
)

Queues an update to the topological ordering to accommodate an edge to be added from SUnit X to SUnit Y.

Definition at line 539 of file ScheduleDAG.cpp.

References X, and Y.

Referenced by llvm::ScheduleDAGInstrs::addEdge().

◆ AddSUnitWithoutPredecessors()

void ScheduleDAGTopologicalSort::AddSUnitWithoutPredecessors ( const SUnit SU)

Add a SUnit without predecessors to the end of the topological order.

It also must be the first new node added to the DAG.

Definition at line 718 of file ScheduleDAG.cpp.

References assert(), llvm::SUnit::NodeNum, llvm::SUnit::NumPreds, and llvm::BitVector::resize().

◆ begin() [1/2]

iterator llvm::ScheduleDAGTopologicalSort::begin ( )
inline

Definition at line 798 of file ScheduleDAG.h.

◆ begin() [2/2]

const_iterator llvm::ScheduleDAGTopologicalSort::begin ( ) const
inline

Definition at line 799 of file ScheduleDAG.h.

◆ end() [1/2]

iterator llvm::ScheduleDAGTopologicalSort::end ( )
inline

Definition at line 800 of file ScheduleDAG.h.

◆ end() [2/2]

const_iterator llvm::ScheduleDAGTopologicalSort::end ( ) const
inline

Definition at line 801 of file ScheduleDAG.h.

◆ GetSubGraph()

std::vector< int > ScheduleDAGTopologicalSort::GetSubGraph ( const SUnit StartSU,
const SUnit TargetSU,
bool Success 
)

Returns an array of SUs that are both in the successor subtree of StartSU and in the predecessor subtree of TargetSU.

StartSU and TargetSU are not in the array. Success is false if TargetSU is not in the successor subtree of StartSU, else it is true.

Definition at line 600 of file ScheduleDAG.cpp.

References assert(), llvm::SUnit::isBoundaryNode(), llvm::SUnit::NodeNum, llvm::SUnit::Preds, llvm::BitVector::push_back(), llvm::BitVector::reset(), llvm::BitVector::resize(), llvm::reverse(), llvm::BitVector::set(), Success, llvm::SUnit::Succs, and llvm::BitVector::test().

◆ InitDAGTopologicalSorting()

void ScheduleDAGTopologicalSort::InitDAGTopologicalSorting ( )

◆ IsReachable()

bool ScheduleDAGTopologicalSort::IsReachable ( const SUnit SU,
const SUnit TargetSU 
)

◆ MarkDirty()

void llvm::ScheduleDAGTopologicalSort::MarkDirty ( )
inline

Mark the ordering as temporarily broken, after a new node has been added.

Definition at line 794 of file ScheduleDAG.h.

Referenced by llvm::ScheduleDAGInstrs::buildSchedGraph().

◆ rbegin() [1/2]

reverse_iterator llvm::ScheduleDAGTopologicalSort::rbegin ( )
inline

Definition at line 805 of file ScheduleDAG.h.

◆ rbegin() [2/2]

const_reverse_iterator llvm::ScheduleDAGTopologicalSort::rbegin ( ) const
inline

Definition at line 806 of file ScheduleDAG.h.

◆ RemovePred()

void ScheduleDAGTopologicalSort::RemovePred ( SUnit M,
SUnit N 
)

Updates the topological ordering to accommodate an edge to be removed from the specified node N from the predecessors of the current node M.

Definition at line 569 of file ScheduleDAG.cpp.

◆ rend() [1/2]

reverse_iterator llvm::ScheduleDAGTopologicalSort::rend ( )
inline

Definition at line 807 of file ScheduleDAG.h.

◆ rend() [2/2]

const_reverse_iterator llvm::ScheduleDAGTopologicalSort::rend ( ) const
inline

Definition at line 808 of file ScheduleDAG.h.

◆ WillCreateCycle()

bool ScheduleDAGTopologicalSort::WillCreateCycle ( SUnit TargetSU,
SUnit SU 
)

Returns true if addPred(TargetSU, SU) creates a cycle.

Definition at line 706 of file ScheduleDAG.cpp.

References llvm::SDep::getSUnit(), llvm::SDep::isAssignedRegDep(), IsReachable(), and llvm::SUnit::Preds.


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