class SchedDFSImpl

Declaration

class SchedDFSImpl { /* full declaration omitted */ };

Description

Internal state used to compute SchedDFSResult.

Declared at: llvm/lib/CodeGen/ScheduleDAGInstrs.cpp:1215

Member Variables

private llvm::SchedDFSResult& R

private llvm::IntEqClasses SubtreeClasses

Join DAG nodes into equivalence classes by their subtree.

private std::vector<std::pair<const SUnit*, const SUnit*>> ConnectionPairs

List PredSU, SuccSU pairs that represent data edges between subtrees.

private SparseSet<llvm::SchedDFSImpl::RootData> RootSet

Method Overview

• public SchedDFSImpl(llvm::SchedDFSResult & r)
• protected void addConnection(unsigned int FromTree, unsigned int ToTree, unsigned int Depth)
• public void finalize()
• public bool isVisited(const llvm::SUnit * SU) const
• protected bool joinPredSubtree(const llvm::SDep & PredDep, const llvm::SUnit * Succ, bool CheckLimit = true)
• public void visitCrossEdge(const llvm::SDep & PredDep, const llvm::SUnit * Succ)
• public void visitPostorderEdge(const llvm::SDep & PredDep, const llvm::SUnit * Succ)
• public void visitPostorderNode(const llvm::SUnit * SU)
• public void visitPreorder(const llvm::SUnit * SU)

Methods

¶SchedDFSImpl(llvm::SchedDFSResult& r)

Declared at: llvm/lib/CodeGen/ScheduleDAGInstrs.cpp:1238

Parameters

llvm::SchedDFSResult& r

¶void addConnection(unsigned int FromTree,
                   unsigned int ToTree,
                   unsigned int Depth)

Description

Called by finalize() to record a connection between trees.

Declared at: llvm/lib/CodeGen/ScheduleDAGInstrs.cpp:1380

Parameters

unsigned int FromTree

unsigned int ToTree

unsigned int Depth

¶void finalize()

Description

Sets each node's subtree ID to the representative ID and record connections between trees.

Declared at: llvm/lib/CodeGen/ScheduleDAGInstrs.cpp:1316

¶bool isVisited(const llvm::SUnit* SU) const

Description

Returns true if this node been visited by the DFS traversal. During visitPostorderNode the Node's SubtreeID is assigned to the Node ID. Later, SubtreeID is updated but remains valid.

Declared at: llvm/lib/CodeGen/ScheduleDAGInstrs.cpp:1246

Parameters

const llvm::SUnit* SU

¶bool joinPredSubtree(const llvm::SDep& PredDep,
                     const llvm::SUnit* Succ,
                     bool CheckLimit = true)

Description

Joins the predecessor subtree with the successor that is its DFS parent. Applies some heuristics before joining.

Declared at: llvm/lib/CodeGen/ScheduleDAGInstrs.cpp:1353

Parameters

const llvm::SDep& PredDep

const llvm::SUnit* Succ

bool CheckLimit = true

¶void visitCrossEdge(const llvm::SDep& PredDep,
                    const llvm::SUnit* Succ)

Description

Adds a connection for cross edges.

Declared at: llvm/lib/CodeGen/ScheduleDAGInstrs.cpp:1310

Parameters

const llvm::SDep& PredDep

const llvm::SUnit* Succ

¶void visitPostorderEdge(const llvm::SDep& PredDep,
                        const llvm::SUnit* Succ)

Description

Called once for each tree edge after calling visitPostOrderNode on the predecessor. Increment the parent node's instruction count and preemptively join this subtree to its parent's if it is small enough.

Declared at: llvm/lib/CodeGen/ScheduleDAGInstrs.cpp:1303

Parameters

const llvm::SDep& PredDep

const llvm::SUnit* Succ

¶void visitPostorderNode(const llvm::SUnit* SU)

Description

Called once for each node after all predecessors are visited. Revisit this node's predecessors and potentially join them now that we know the ILP of the other predecessors.

Declared at: llvm/lib/CodeGen/ScheduleDAGInstrs.cpp:1261

Parameters

const llvm::SUnit* SU

¶void visitPreorder(const llvm::SUnit* SU)

Description

Initializes this node's instruction count. We don't need to flag the node visited until visitPostorder because the DAG cannot have cycles.

Declared at: llvm/lib/CodeGen/ScheduleDAGInstrs.cpp:1253

Parameters

const llvm::SUnit* SU