#include "llvm/Target/TargetInstrInfo.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/Compiler.h"
+#include "llvm/ADT/BitVector.h"
+#include "llvm/ADT/PriorityQueue.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/SmallSet.h"
#include "llvm/ADT/Statistic.h"
+#include "llvm/ADT/STLExtras.h"
#include <climits>
-#include <queue>
#include "llvm/Support/CommandLine.h"
using namespace llvm;
void Schedule();
+ /// IsReachable - Checks if SU is reachable from TargetSU.
+ bool IsReachable(SUnit *SU, SUnit *TargetSU);
+
+ /// willCreateCycle - Returns true if adding an edge from SU to TargetSU will
+ /// create a cycle.
+ bool WillCreateCycle(SUnit *SU, SUnit *TargetSU);
+
+ /// AddPred - This adds the specified node X as a predecessor of
+ /// the current node Y if not already.
+ /// This returns true if this is a new predecessor.
+ /// Updates the topological ordering if required.
+ bool AddPred(SUnit *Y, SUnit *X, bool isCtrl, bool isSpecial,
+ unsigned PhyReg = 0, int Cost = 1);
+
+ /// RemovePred - This removes the specified node N from the predecessors of
+ /// the current node M. Updates the topological ordering if required.
+ bool RemovePred(SUnit *M, SUnit *N, bool isCtrl, bool isSpecial);
+
private:
void ReleasePred(SUnit*, bool, unsigned);
void ReleaseSucc(SUnit*, bool isChain, unsigned);
void ListScheduleTopDown();
void ListScheduleBottomUp();
void CommuteNodesToReducePressure();
+
+
+ /// CreateNewSUnit - Creates a new SUnit and returns a pointer to it.
+ /// Updates the topological ordering if required.
+ SUnit *CreateNewSUnit(SDNode *N) {
+ SUnit *NewNode = NewSUnit(N);
+ // Update the topological ordering.
+ if (NewNode->NodeNum >= Node2Index.size())
+ InitDAGTopologicalSorting();
+ return NewNode;
+ }
+
+ /// CreateClone - Creates a new SUnit from an existing one.
+ /// Updates the topological ordering if required.
+ SUnit *CreateClone(SUnit *N) {
+ SUnit *NewNode = Clone(N);
+ // Update the topological ordering.
+ if (NewNode->NodeNum >= Node2Index.size())
+ InitDAGTopologicalSorting();
+ return NewNode;
+ }
+
+ /// Functions for preserving the topological ordering
+ /// even after dynamic insertions of new edges.
+ /// This allows a very fast implementation of IsReachable.
+
+
+ /**
+ The idea of the algorithm is taken from
+ "Online algorithms for managing the topological order of
+ a directed acyclic graph" by David J. Pearce and Paul H.J. Kelly
+ This is the MNR algorithm, which was first introduced by
+ A. Marchetti-Spaccamela, U. Nanni and H. Rohnert in
+ "Maintaining a topological order under edge insertions".
+
+ Short description of the algorithm:
+
+ Topological ordering, ord, of a DAG maps each node to a topological
+ index so that for all edges X->Y it is the case that ord(X) < ord(Y).
+
+ This means that if there is a path from the node X to the node Z,
+ then ord(X) < ord(Z).
+
+ This property can be used to check for reachability of nodes:
+ if Z is reachable from X, then an insertion of the edge Z->X would
+ create a cycle.
+
+ The algorithm first computes a topological ordering for the DAG by initializing
+ the Index2Node and Node2Index arrays and then tries to keep the ordering
+ up-to-date after edge insertions by reordering the DAG.
+
+ On insertion of the edge X->Y, the algorithm first marks by calling DFS the
+ nodes reachable from Y, and then shifts them using Shift to lie immediately
+ after X in Index2Node.
+ */
+
+ /// InitDAGTopologicalSorting - create the initial topological
+ /// ordering from the DAG to be scheduled.
+ void InitDAGTopologicalSorting();
+
+ /// DFS - make a DFS traversal and mark all nodes affected by the
+ /// edge insertion. These nodes will later get new topological indexes
+ /// by means of the Shift method.
+ void DFS(SUnit *SU, int UpperBound, bool& HasLoop);
+
+ /// Shift - reassign topological indexes for the nodes in the DAG
+ /// to preserve the topological ordering.
+ void Shift(BitVector& Visited, int LowerBound, int UpperBound);
+
+ /// Allocate - assign the topological index to the node n.
+ void Allocate(int n, int index);
+
+ /// Index2Node - Maps topological index to the node number.
+ std::vector<int> Index2Node;
+ /// Node2Index - Maps the node number to its topological index.
+ std::vector<int> Node2Index;
+ /// Visited - a set of nodes visited during a DFS traversal.
+ BitVector Visited;
};
} // end anonymous namespace
SUnits[su].dumpAll(&DAG));
CalculateDepths();
CalculateHeights();
+ InitDAGTopologicalSorting();
- AvailableQueue->initNodes(SUnitMap, SUnits);
+ AvailableQueue->initNodes(SUnits);
// Execute the actual scheduling loop Top-Down or Bottom-Up as appropriate.
if (isBottomUp)
/// possible. It will be commuted when it is translated to a MI.
void ScheduleDAGRRList::CommuteNodesToReducePressure() {
SmallPtrSet<SUnit*, 4> OperandSeen;
- for (unsigned i = Sequence.size()-1; i != 0; --i) { // Ignore first node.
+ for (unsigned i = Sequence.size(); i != 0; ) {
+ --i;
SUnit *SU = Sequence[i];
if (!SU || !SU->Node) continue;
if (SU->isCommutable) {
continue;
SDNode *OpN = SU->Node->getOperand(j).Val;
- SUnit *OpSU = isPassiveNode(OpN) ? NULL : SUnitMap[OpN][SU->InstanceNo];
+ SUnit *OpSU = isPassiveNode(OpN) ? NULL : &SUnits[OpN->getNodeId()];
if (OpSU && OperandSeen.count(OpSU) == 1) {
// Ok, so SU is not the last use of OpSU, but SU is two-address so
// it will clobber OpSU. Try to commute SU if no other source operands
for (unsigned k = 0; k < NumOps; ++k) {
if (k != j) {
OpN = SU->Node->getOperand(k).Val;
- OpSU = isPassiveNode(OpN) ? NULL : SUnitMap[OpN][SU->InstanceNo];
+ OpSU = isPassiveNode(OpN) ? NULL : &SUnits[OpN->getNodeId()];
if (OpSU && OperandSeen.count(OpSU) == 1) {
DoCommute = false;
break;
for (SUnit::pred_iterator I = SU->Preds.begin(), E = SU->Preds.end();
I != E; ++I) {
if (!I->isCtrl)
- OperandSeen.insert(I->Dep);
+ OperandSeen.insert(I->Dep->OrigNode);
}
}
}
#endif
if (PredSU->NumSuccsLeft == 0) {
- // EntryToken has to go last! Special case it here.
- if (!PredSU->Node || PredSU->Node->getOpcode() != ISD::EntryToken) {
- PredSU->isAvailable = true;
- AvailableQueue->push(PredSU);
- }
+ PredSU->isAvailable = true;
+ AvailableQueue->push(PredSU);
}
}
/// CapturePred - This does the opposite of ReleasePred. Since SU is being
/// unscheduled, incrcease the succ left count of its predecessors. Remove
/// them from AvailableQueue if necessary.
-void ScheduleDAGRRList::CapturePred(SUnit *PredSU, SUnit *SU, bool isChain) {
- PredSU->CycleBound = 0;
+void ScheduleDAGRRList::CapturePred(SUnit *PredSU, SUnit *SU, bool isChain) {
+ unsigned CycleBound = 0;
for (SUnit::succ_iterator I = PredSU->Succs.begin(), E = PredSU->Succs.end();
I != E; ++I) {
if (I->Dep == SU)
continue;
- PredSU->CycleBound = std::max(PredSU->CycleBound,
- I->Dep->Cycle + PredSU->Latency);
+ CycleBound = std::max(CycleBound,
+ I->Dep->Cycle + PredSU->Latency);
}
if (PredSU->isAvailable) {
AvailableQueue->remove(PredSU);
}
+ PredSU->CycleBound = CycleBound;
++PredSU->NumSuccsLeft;
}
AvailableQueue->push(SU);
}
-// FIXME: This is probably too slow!
-static void isReachable(SUnit *SU, SUnit *TargetSU,
- SmallPtrSet<SUnit*, 32> &Visited, bool &Reached) {
- if (Reached) return;
- if (SU == TargetSU) {
- Reached = true;
- return;
+/// IsReachable - Checks if SU is reachable from TargetSU.
+bool ScheduleDAGRRList::IsReachable(SUnit *SU, SUnit *TargetSU) {
+ // If insertion of the edge SU->TargetSU would create a cycle
+ // then there is a path from TargetSU to SU.
+ int UpperBound, LowerBound;
+ LowerBound = Node2Index[TargetSU->NodeNum];
+ UpperBound = Node2Index[SU->NodeNum];
+ bool HasLoop = false;
+ // Is Ord(TargetSU) < Ord(SU) ?
+ if (LowerBound < UpperBound) {
+ Visited.reset();
+ // There may be a path from TargetSU to SU. Check for it.
+ DFS(TargetSU, UpperBound, HasLoop);
}
- if (!Visited.insert(SU)) return;
+ return HasLoop;
+}
- for (SUnit::pred_iterator I = SU->Preds.begin(), E = SU->Preds.end(); I != E;
- ++I)
- isReachable(I->Dep, TargetSU, Visited, Reached);
+/// Allocate - assign the topological index to the node n.
+inline void ScheduleDAGRRList::Allocate(int n, int index) {
+ Node2Index[n] = index;
+ Index2Node[index] = n;
}
-static bool isReachable(SUnit *SU, SUnit *TargetSU) {
- SmallPtrSet<SUnit*, 32> Visited;
- bool Reached = false;
- isReachable(SU, TargetSU, Visited, Reached);
- return Reached;
+/// InitDAGTopologicalSorting - create the initial topological
+/// ordering from the DAG to be scheduled.
+void ScheduleDAGRRList::InitDAGTopologicalSorting() {
+ unsigned DAGSize = SUnits.size();
+ std::vector<unsigned> InDegree(DAGSize);
+ std::vector<SUnit*> WorkList;
+ WorkList.reserve(DAGSize);
+ std::vector<SUnit*> TopOrder;
+ TopOrder.reserve(DAGSize);
+
+ // Initialize the data structures.
+ for (unsigned i = 0, e = DAGSize; i != e; ++i) {
+ SUnit *SU = &SUnits[i];
+ int NodeNum = SU->NodeNum;
+ unsigned Degree = SU->Succs.size();
+ InDegree[NodeNum] = Degree;
+
+ // Is it a node without dependencies?
+ if (Degree == 0) {
+ assert(SU->Succs.empty() && "SUnit should have no successors");
+ // Collect leaf nodes.
+ WorkList.push_back(SU);
+ }
+ }
+
+ while (!WorkList.empty()) {
+ SUnit *SU = WorkList.back();
+ WorkList.pop_back();
+ TopOrder.push_back(SU);
+ for (SUnit::const_pred_iterator I = SU->Preds.begin(), E = SU->Preds.end();
+ I != E; ++I) {
+ SUnit *SU = I->Dep;
+ if (!--InDegree[SU->NodeNum])
+ // If all dependencies of the node are processed already,
+ // then the node can be computed now.
+ WorkList.push_back(SU);
+ }
+ }
+
+ // Second pass, assign the actual topological order as node ids.
+ int Id = 0;
+
+ Index2Node.clear();
+ Node2Index.clear();
+ Index2Node.resize(DAGSize);
+ Node2Index.resize(DAGSize);
+ Visited.resize(DAGSize);
+
+ for (std::vector<SUnit*>::reverse_iterator TI = TopOrder.rbegin(),
+ TE = TopOrder.rend();TI != TE; ++TI) {
+ Allocate((*TI)->NodeNum, Id);
+ Id++;
+ }
+
+#ifndef NDEBUG
+ // Check correctness of the ordering
+ for (unsigned i = 0, e = DAGSize; i != e; ++i) {
+ SUnit *SU = &SUnits[i];
+ for (SUnit::const_pred_iterator I = SU->Preds.begin(), E = SU->Preds.end();
+ I != E; ++I) {
+ assert(Node2Index[SU->NodeNum] > Node2Index[I->Dep->NodeNum] &&
+ "Wrong topological sorting");
+ }
+ }
+#endif
+}
+
+/// AddPred - adds an edge from SUnit X to SUnit Y.
+/// Updates the topological ordering if required.
+bool ScheduleDAGRRList::AddPred(SUnit *Y, SUnit *X, bool isCtrl, bool isSpecial,
+ unsigned PhyReg, int Cost) {
+ int UpperBound, LowerBound;
+ LowerBound = Node2Index[Y->NodeNum];
+ UpperBound = Node2Index[X->NodeNum];
+ bool HasLoop = false;
+ // Is Ord(X) < Ord(Y) ?
+ if (LowerBound < UpperBound) {
+ // Update the topological order.
+ Visited.reset();
+ DFS(Y, UpperBound, HasLoop);
+ assert(!HasLoop && "Inserted edge creates a loop!");
+ // Recompute topological indexes.
+ Shift(Visited, LowerBound, UpperBound);
+ }
+ // Now really insert the edge.
+ return Y->addPred(X, isCtrl, isSpecial, PhyReg, Cost);
+}
+
+/// RemovePred - This removes the specified node N from the predecessors of
+/// the current node M. Updates the topological ordering if required.
+bool ScheduleDAGRRList::RemovePred(SUnit *M, SUnit *N,
+ bool isCtrl, bool isSpecial) {
+ // InitDAGTopologicalSorting();
+ return M->removePred(N, isCtrl, isSpecial);
+}
+
+/// DFS - Make a DFS traversal to mark all nodes reachable from SU and mark
+/// all nodes affected by the edge insertion. These nodes will later get new
+/// topological indexes by means of the Shift method.
+void ScheduleDAGRRList::DFS(SUnit *SU, int UpperBound, bool& HasLoop) {
+ std::vector<SUnit*> WorkList;
+ WorkList.reserve(SUnits.size());
+
+ WorkList.push_back(SU);
+ while (!WorkList.empty()) {
+ SU = WorkList.back();
+ WorkList.pop_back();
+ Visited.set(SU->NodeNum);
+ for (int I = SU->Succs.size()-1; I >= 0; --I) {
+ int s = SU->Succs[I].Dep->NodeNum;
+ if (Node2Index[s] == UpperBound) {
+ HasLoop = true;
+ return;
+ }
+ // Visit successors if not already and in affected region.
+ if (!Visited.test(s) && Node2Index[s] < UpperBound) {
+ WorkList.push_back(SU->Succs[I].Dep);
+ }
+ }
+ }
+}
+
+/// Shift - Renumber the nodes so that the topological ordering is
+/// preserved.
+void ScheduleDAGRRList::Shift(BitVector& Visited, int LowerBound,
+ int UpperBound) {
+ std::vector<int> L;
+ int shift = 0;
+ int i;
+
+ for (i = LowerBound; i <= UpperBound; ++i) {
+ // w is node at topological index i.
+ int w = Index2Node[i];
+ if (Visited.test(w)) {
+ // Unmark.
+ Visited.reset(w);
+ L.push_back(w);
+ shift = shift + 1;
+ } else {
+ Allocate(w, i - shift);
+ }
+ }
+
+ for (unsigned j = 0; j < L.size(); ++j) {
+ Allocate(L[j], i - shift);
+ i = i + 1;
+ }
}
+
/// WillCreateCycle - Returns true if adding an edge from SU to TargetSU will
/// create a cycle.
-static bool WillCreateCycle(SUnit *SU, SUnit *TargetSU) {
- if (isReachable(TargetSU, SU))
+bool ScheduleDAGRRList::WillCreateCycle(SUnit *SU, SUnit *TargetSU) {
+ if (IsReachable(TargetSU, SU))
return true;
for (SUnit::pred_iterator I = SU->Preds.begin(), E = SU->Preds.end();
I != E; ++I)
- if (I->Cost < 0 && isReachable(TargetSU, I->Dep))
+ if (I->Cost < 0 && IsReachable(TargetSU, I->Dep))
return true;
return false;
}
SUnit *NewSU;
bool TryUnfold = false;
for (unsigned i = 0, e = N->getNumValues(); i != e; ++i) {
- MVT::ValueType VT = N->getValueType(i);
+ MVT VT = N->getValueType(i);
if (VT == MVT::Flag)
return NULL;
else if (VT == MVT::Other)
}
for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
const SDOperand &Op = N->getOperand(i);
- MVT::ValueType VT = Op.Val->getValueType(Op.ResNo);
+ MVT VT = Op.Val->getValueType(Op.ResNo);
if (VT == MVT::Flag)
return NULL;
}
if (TryUnfold) {
- SmallVector<SDNode*, 4> NewNodes;
+ SmallVector<SDNode*, 2> NewNodes;
if (!TII->unfoldMemoryOperand(DAG, N, NewNodes))
return NULL;
DAG.ReplaceAllUsesOfValueWith(SDOperand(SU->Node, OldNumVals-1),
SDOperand(LoadNode, 1));
- SUnit *NewSU = NewSUnit(N);
- SUnitMap[N].push_back(NewSU);
+ SUnit *NewSU = CreateNewSUnit(N);
+ assert(N->getNodeId() == -1 && "Node already inserted!");
+ N->setNodeId(NewSU->NodeNum);
+
const TargetInstrDesc &TID = TII->get(N->getTargetOpcode());
for (unsigned i = 0; i != TID.getNumOperands(); ++i) {
if (TID.getOperandConstraint(i, TOI::TIED_TO) != -1) {
// but it has different alignment or volatileness.
bool isNewLoad = true;
SUnit *LoadSU;
- DenseMap<SDNode*, std::vector<SUnit*> >::iterator SMI =
- SUnitMap.find(LoadNode);
- if (SMI != SUnitMap.end()) {
- LoadSU = SMI->second.front();
+ if (LoadNode->getNodeId() != -1) {
+ LoadSU = &SUnits[LoadNode->getNodeId()];
isNewLoad = false;
} else {
- LoadSU = NewSUnit(LoadNode);
- SUnitMap[LoadNode].push_back(LoadSU);
+ LoadSU = CreateNewSUnit(LoadNode);
+ LoadNode->setNodeId(LoadSU->NodeNum);
LoadSU->Depth = SU->Depth;
LoadSU->Height = SU->Height;
I->isCtrl, I->isSpecial));
}
- SU->removePred(ChainPred, true, false);
- if (isNewLoad)
- LoadSU->addPred(ChainPred, true, false);
+ if (ChainPred) {
+ RemovePred(SU, ChainPred, true, false);
+ if (isNewLoad)
+ AddPred(LoadSU, ChainPred, true, false);
+ }
for (unsigned i = 0, e = LoadPreds.size(); i != e; ++i) {
SDep *Pred = &LoadPreds[i];
- SU->removePred(Pred->Dep, Pred->isCtrl, Pred->isSpecial);
- if (isNewLoad)
- LoadSU->addPred(Pred->Dep, Pred->isCtrl, Pred->isSpecial,
- Pred->Reg, Pred->Cost);
+ RemovePred(SU, Pred->Dep, Pred->isCtrl, Pred->isSpecial);
+ if (isNewLoad) {
+ AddPred(LoadSU, Pred->Dep, Pred->isCtrl, Pred->isSpecial,
+ Pred->Reg, Pred->Cost);
+ }
}
for (unsigned i = 0, e = NodePreds.size(); i != e; ++i) {
SDep *Pred = &NodePreds[i];
- SU->removePred(Pred->Dep, Pred->isCtrl, Pred->isSpecial);
- NewSU->addPred(Pred->Dep, Pred->isCtrl, Pred->isSpecial,
- Pred->Reg, Pred->Cost);
+ RemovePred(SU, Pred->Dep, Pred->isCtrl, Pred->isSpecial);
+ AddPred(NewSU, Pred->Dep, Pred->isCtrl, Pred->isSpecial,
+ Pred->Reg, Pred->Cost);
}
for (unsigned i = 0, e = NodeSuccs.size(); i != e; ++i) {
SDep *Succ = &NodeSuccs[i];
- Succ->Dep->removePred(SU, Succ->isCtrl, Succ->isSpecial);
- Succ->Dep->addPred(NewSU, Succ->isCtrl, Succ->isSpecial,
- Succ->Reg, Succ->Cost);
+ RemovePred(Succ->Dep, SU, Succ->isCtrl, Succ->isSpecial);
+ AddPred(Succ->Dep, NewSU, Succ->isCtrl, Succ->isSpecial,
+ Succ->Reg, Succ->Cost);
}
for (unsigned i = 0, e = ChainSuccs.size(); i != e; ++i) {
SDep *Succ = &ChainSuccs[i];
- Succ->Dep->removePred(SU, Succ->isCtrl, Succ->isSpecial);
- if (isNewLoad)
- Succ->Dep->addPred(LoadSU, Succ->isCtrl, Succ->isSpecial,
- Succ->Reg, Succ->Cost);
+ RemovePred(Succ->Dep, SU, Succ->isCtrl, Succ->isSpecial);
+ if (isNewLoad) {
+ AddPred(Succ->Dep, LoadSU, Succ->isCtrl, Succ->isSpecial,
+ Succ->Reg, Succ->Cost);
+ }
}
- if (isNewLoad)
- NewSU->addPred(LoadSU, false, false);
+ if (isNewLoad) {
+ AddPred(NewSU, LoadSU, false, false);
+ }
if (isNewLoad)
AvailableQueue->addNode(LoadSU);
}
DOUT << "Duplicating SU # " << SU->NodeNum << "\n";
- NewSU = Clone(SU);
+ NewSU = CreateClone(SU);
// New SUnit has the exact same predecessors.
for (SUnit::pred_iterator I = SU->Preds.begin(), E = SU->Preds.end();
I != E; ++I)
if (!I->isSpecial) {
- NewSU->addPred(I->Dep, I->isCtrl, false, I->Reg, I->Cost);
+ AddPred(NewSU, I->Dep, I->isCtrl, false, I->Reg, I->Cost);
NewSU->Depth = std::max(NewSU->Depth, I->Dep->Depth+1);
}
continue;
if (I->Dep->isScheduled) {
NewSU->Height = std::max(NewSU->Height, I->Dep->Height+1);
- I->Dep->addPred(NewSU, I->isCtrl, false, I->Reg, I->Cost);
+ AddPred(I->Dep, NewSU, I->isCtrl, false, I->Reg, I->Cost);
DelDeps.push_back(std::make_pair(I->Dep, I->isCtrl));
}
}
for (unsigned i = 0, e = DelDeps.size(); i != e; ++i) {
SUnit *Succ = DelDeps[i].first;
bool isCtrl = DelDeps[i].second;
- Succ->removePred(SU, isCtrl, false);
+ RemovePred(Succ, SU, isCtrl, false);
}
AvailableQueue->updateNode(SU);
const TargetRegisterClass *DestRC,
const TargetRegisterClass *SrcRC,
SmallVector<SUnit*, 2> &Copies) {
- SUnit *CopyFromSU = NewSUnit(NULL);
+ SUnit *CopyFromSU = CreateNewSUnit(NULL);
CopyFromSU->CopySrcRC = SrcRC;
CopyFromSU->CopyDstRC = DestRC;
CopyFromSU->Depth = SU->Depth;
CopyFromSU->Height = SU->Height;
- SUnit *CopyToSU = NewSUnit(NULL);
+ SUnit *CopyToSU = CreateNewSUnit(NULL);
CopyToSU->CopySrcRC = DestRC;
CopyToSU->CopyDstRC = SrcRC;
continue;
if (I->Dep->isScheduled) {
CopyToSU->Height = std::max(CopyToSU->Height, I->Dep->Height+1);
- I->Dep->addPred(CopyToSU, I->isCtrl, false, I->Reg, I->Cost);
+ AddPred(I->Dep, CopyToSU, I->isCtrl, false, I->Reg, I->Cost);
DelDeps.push_back(std::make_pair(I->Dep, I->isCtrl));
}
}
for (unsigned i = 0, e = DelDeps.size(); i != e; ++i) {
SUnit *Succ = DelDeps[i].first;
bool isCtrl = DelDeps[i].second;
- Succ->removePred(SU, isCtrl, false);
+ RemovePred(Succ, SU, isCtrl, false);
}
- CopyFromSU->addPred(SU, false, false, Reg, -1);
- CopyToSU->addPred(CopyFromSU, false, false, Reg, 1);
+ AddPred(CopyFromSU, SU, false, false, Reg, -1);
+ AddPred(CopyToSU, CopyFromSU, false, false, Reg, 1);
AvailableQueue->updateNode(SU);
AvailableQueue->addNode(CopyFromSU);
/// getPhysicalRegisterVT - Returns the ValueType of the physical register
/// definition of the specified node.
/// FIXME: Move to SelectionDAG?
-static MVT::ValueType getPhysicalRegisterVT(SDNode *N, unsigned Reg,
- const TargetInstrInfo *TII) {
+static MVT getPhysicalRegisterVT(SDNode *N, unsigned Reg,
+ const TargetInstrInfo *TII) {
const TargetInstrDesc &TID = TII->get(N->getTargetOpcode());
assert(TID.ImplicitDefs && "Physical reg def must be in implicit def list!");
unsigned NumRes = TID.getNumDefs();
void ScheduleDAGRRList::ListScheduleBottomUp() {
unsigned CurCycle = 0;
// Add root to Available queue.
- SUnit *RootSU = SUnitMap[DAG.getRoot().Val].front();
- RootSU->isAvailable = true;
- AvailableQueue->push(RootSU);
+ if (!SUnits.empty()) {
+ SUnit *RootSU = &SUnits[DAG.getRoot().Val->getNodeId()];
+ assert(RootSU->Succs.empty() && "Graph root shouldn't have successors!");
+ RootSU->isAvailable = true;
+ AvailableQueue->push(RootSU);
+ }
// While Available queue is not empty, grab the node with the highest
// priority. If it is not ready put it back. Schedule the node.
SmallVector<SUnit*, 4> NotReady;
+ Sequence.reserve(SUnits.size());
while (!AvailableQueue->empty()) {
bool Delayed = false;
DenseMap<SUnit*, SmallVector<unsigned, 4> > LRegsMap;
OldSU->isAvailable = false;
AvailableQueue->remove(OldSU);
}
- TrySU->addPred(OldSU, true, true);
+ AddPred(TrySU, OldSU, true, true);
// If one or more successors has been unscheduled, then the current
// node is no longer avaialable. Schedule a successor that's now
// available instead.
SUnit *NewDef = CopyAndMoveSuccessors(LRDef);
if (!NewDef) {
// Issue expensive cross register class copies.
- MVT::ValueType VT = getPhysicalRegisterVT(LRDef->Node, Reg, TII);
+ MVT VT = getPhysicalRegisterVT(LRDef->Node, Reg, TII);
const TargetRegisterClass *RC =
TRI->getPhysicalRegisterRegClass(Reg, VT);
const TargetRegisterClass *DestRC = TRI->getCrossCopyRegClass(RC);
InsertCCCopiesAndMoveSuccs(LRDef, Reg, DestRC, RC, Copies);
DOUT << "Adding an edge from SU # " << TrySU->NodeNum
<< " to SU #" << Copies.front()->NodeNum << "\n";
- TrySU->addPred(Copies.front(), true, true);
+ AddPred(TrySU, Copies.front(), true, true);
NewDef = Copies.back();
}
DOUT << "Adding an edge from SU # " << NewDef->NodeNum
<< " to SU #" << TrySU->NodeNum << "\n";
LiveRegDefs[Reg] = NewDef;
- NewDef->addPred(TrySU, true, true);
+ AddPred(NewDef, TrySU, true, true);
TrySU->isAvailable = false;
CurSU = NewDef;
}
++CurCycle;
}
- // Add entry node last
- if (DAG.getEntryNode().Val != DAG.getRoot().Val) {
- SUnit *Entry = SUnitMap[DAG.getEntryNode().Val].front();
- Sequence.push_back(Entry);
- }
-
// Reverse the order if it is bottom up.
std::reverse(Sequence.begin(), Sequence.end());
#ifndef NDEBUG
// Verify that all SUnits were scheduled.
bool AnyNotSched = false;
+ unsigned DeadNodes = 0;
+ unsigned Noops = 0;
for (unsigned i = 0, e = SUnits.size(); i != e; ++i) {
- if (SUnits[i].NumSuccsLeft != 0) {
+ if (!SUnits[i].isScheduled) {
+ if (SUnits[i].NumPreds == 0 && SUnits[i].NumSuccs == 0) {
+ ++DeadNodes;
+ continue;
+ }
if (!AnyNotSched)
cerr << "*** List scheduling failed! ***\n";
SUnits[i].dump(&DAG);
cerr << "has not been scheduled!\n";
AnyNotSched = true;
}
+ if (SUnits[i].NumSuccsLeft != 0) {
+ if (!AnyNotSched)
+ cerr << "*** List scheduling failed! ***\n";
+ SUnits[i].dump(&DAG);
+ cerr << "has successors left!\n";
+ AnyNotSched = true;
+ }
}
+ for (unsigned i = 0, e = Sequence.size(); i != e; ++i)
+ if (!Sequence[i])
+ ++Noops;
assert(!AnyNotSched);
+ assert(Sequence.size() + DeadNodes - Noops == SUnits.size() &&
+ "The number of nodes scheduled doesn't match the expected number!");
#endif
}
/// schedulers.
void ScheduleDAGRRList::ListScheduleTopDown() {
unsigned CurCycle = 0;
- SUnit *Entry = SUnitMap[DAG.getEntryNode().Val].front();
// All leaves to Available queue.
for (unsigned i = 0, e = SUnits.size(); i != e; ++i) {
// It is available if it has no predecessors.
- if (SUnits[i].Preds.empty() && &SUnits[i] != Entry) {
+ if (SUnits[i].Preds.empty()) {
AvailableQueue->push(&SUnits[i]);
SUnits[i].isAvailable = true;
}
}
- // Emit the entry node first.
- ScheduleNodeTopDown(Entry, CurCycle);
- Sequence.push_back(Entry);
- ++CurCycle;
-
// While Available queue is not empty, grab the node with the highest
// priority. If it is not ready put it back. Schedule the node.
std::vector<SUnit*> NotReady;
+ Sequence.reserve(SUnits.size());
while (!AvailableQueue->empty()) {
SUnit *CurSU = AvailableQueue->pop();
while (CurSU && CurSU->CycleBound > CurCycle) {
ScheduleNodeTopDown(CurSU, CurCycle);
Sequence.push_back(CurSU);
}
- CurCycle++;
+ ++CurCycle;
}
#ifndef NDEBUG
// Verify that all SUnits were scheduled.
bool AnyNotSched = false;
+ unsigned DeadNodes = 0;
+ unsigned Noops = 0;
for (unsigned i = 0, e = SUnits.size(); i != e; ++i) {
if (!SUnits[i].isScheduled) {
+ if (SUnits[i].NumPreds == 0 && SUnits[i].NumSuccs == 0) {
+ ++DeadNodes;
+ continue;
+ }
if (!AnyNotSched)
cerr << "*** List scheduling failed! ***\n";
SUnits[i].dump(&DAG);
cerr << "has not been scheduled!\n";
AnyNotSched = true;
}
+ if (SUnits[i].NumPredsLeft != 0) {
+ if (!AnyNotSched)
+ cerr << "*** List scheduling failed! ***\n";
+ SUnits[i].dump(&DAG);
+ cerr << "has predecessors left!\n";
+ AnyNotSched = true;
+ }
}
+ for (unsigned i = 0, e = Sequence.size(); i != e; ++i)
+ if (!Sequence[i])
+ ++Noops;
assert(!AnyNotSched);
+ assert(Sequence.size() + DeadNodes - Noops == SUnits.size() &&
+ "The number of nodes scheduled doesn't match the expected number!");
#endif
}
template<class SF>
class VISIBILITY_HIDDEN RegReductionPriorityQueue
: public SchedulingPriorityQueue {
- std::priority_queue<SUnit*, std::vector<SUnit*>, SF> Queue;
+ PriorityQueue<SUnit*, std::vector<SUnit*>, SF> Queue;
+ unsigned currentQueueId;
public:
RegReductionPriorityQueue() :
- Queue(SF(this)) {}
+ Queue(SF(this)), currentQueueId(0) {}
- virtual void initNodes(DenseMap<SDNode*, std::vector<SUnit*> > &sumap,
- std::vector<SUnit> &sunits) {}
+ virtual void initNodes(std::vector<SUnit> &sunits) {}
virtual void addNode(const SUnit *SU) {}
bool empty() const { return Queue.empty(); }
void push(SUnit *U) {
+ assert(!U->NodeQueueId && "Node in the queue already");
+ U->NodeQueueId = ++currentQueueId;
Queue.push(U);
}
+
void push_all(const std::vector<SUnit *> &Nodes) {
for (unsigned i = 0, e = Nodes.size(); i != e; ++i)
- Queue.push(Nodes[i]);
+ push(Nodes[i]);
}
SUnit *pop() {
if (empty()) return NULL;
SUnit *V = Queue.top();
Queue.pop();
+ V->NodeQueueId = 0;
return V;
}
- /// remove - This is a really inefficient way to remove a node from a
- /// priority queue. We should roll our own heap to make this better or
- /// something.
void remove(SUnit *SU) {
- std::vector<SUnit*> Temp;
-
- assert(!Queue.empty() && "Not in queue!");
- while (Queue.top() != SU) {
- Temp.push_back(Queue.top());
- Queue.pop();
- assert(!Queue.empty() && "Not in queue!");
- }
-
- // Remove the node from the PQ.
- Queue.pop();
-
- // Add all the other nodes back.
- for (unsigned i = 0, e = Temp.size(); i != e; ++i)
- Queue.push(Temp[i]);
+ assert(!Queue.empty() && "Queue is empty!");
+ assert(SU->NodeQueueId != 0 && "Not in queue!");
+ Queue.erase_one(SU);
+ SU->NodeQueueId = 0;
}
};
- template<class SF>
class VISIBILITY_HIDDEN BURegReductionPriorityQueue
- : public RegReductionPriorityQueue<SF> {
- // SUnitMap SDNode to SUnit mapping (n -> n).
- DenseMap<SDNode*, std::vector<SUnit*> > *SUnitMap;
-
+ : public RegReductionPriorityQueue<bu_ls_rr_sort> {
// SUnits - The SUnits for the current graph.
const std::vector<SUnit> *SUnits;
const TargetInstrInfo *TII;
const TargetRegisterInfo *TRI;
+ ScheduleDAGRRList *scheduleDAG;
public:
explicit BURegReductionPriorityQueue(const TargetInstrInfo *tii,
const TargetRegisterInfo *tri)
- : TII(tii), TRI(tri) {}
+ : TII(tii), TRI(tri), scheduleDAG(NULL) {}
- void initNodes(DenseMap<SDNode*, std::vector<SUnit*> > &sumap,
- std::vector<SUnit> &sunits) {
- SUnitMap = &sumap;
+ void initNodes(std::vector<SUnit> &sunits) {
SUnits = &sunits;
// Add pseudo dependency edges for two-address nodes.
AddPseudoTwoAddrDeps();
return SethiUllmanNumbers[SU->NodeNum];
}
+ void setScheduleDAG(ScheduleDAGRRList *scheduleDag) {
+ scheduleDAG = scheduleDag;
+ }
+
private:
bool canClobber(const SUnit *SU, const SUnit *Op);
void AddPseudoTwoAddrDeps();
};
- template<class SF>
class VISIBILITY_HIDDEN TDRegReductionPriorityQueue
- : public RegReductionPriorityQueue<SF> {
- // SUnitMap SDNode to SUnit mapping (n -> n).
- DenseMap<SDNode*, std::vector<SUnit*> > *SUnitMap;
-
+ : public RegReductionPriorityQueue<td_ls_rr_sort> {
// SUnits - The SUnits for the current graph.
const std::vector<SUnit> *SUnits;
public:
TDRegReductionPriorityQueue() {}
- void initNodes(DenseMap<SDNode*, std::vector<SUnit*> > &sumap,
- std::vector<SUnit> &sunits) {
- SUnitMap = &sumap;
+ void initNodes(std::vector<SUnit> &sunits) {
SUnits = &sunits;
// Calculate node priorities.
CalculateSethiUllmanNumbers();
// Bottom up
bool bu_ls_rr_sort::operator()(const SUnit *left, const SUnit *right) const {
- // There used to be a special tie breaker here that looked for
- // two-address instructions and preferred the instruction with a
- // def&use operand. The special case triggered diagnostics when
- // _GLIBCXX_DEBUG was enabled because it broke the strict weak
- // ordering that priority_queue requires. It didn't help much anyway
- // because AddPseudoTwoAddrDeps already covers many of the cases
- // where it would have applied. In addition, it's counter-intuitive
- // that a tie breaker would be the first thing attempted. There's a
- // "real" tie breaker below that is the operation of last resort.
- // The fact that the "special tie breaker" would trigger when there
- // wasn't otherwise a tie is what broke the strict weak ordering
- // constraint.
unsigned LPriority = SPQ->getNodePriority(left);
unsigned RPriority = SPQ->getNodePriority(right);
if (left->CycleBound != right->CycleBound)
return left->CycleBound > right->CycleBound;
- // FIXME: No strict ordering.
- return false;
+ assert(left->NodeQueueId && right->NodeQueueId &&
+ "NodeQueueId cannot be zero");
+ return (left->NodeQueueId > right->NodeQueueId);
}
-template<class SF> bool
-BURegReductionPriorityQueue<SF>::canClobber(const SUnit *SU, const SUnit *Op) {
+bool
+BURegReductionPriorityQueue::canClobber(const SUnit *SU, const SUnit *Op) {
if (SU->isTwoAddress) {
unsigned Opc = SU->Node->getTargetOpcode();
const TargetInstrDesc &TID = TII->get(Opc);
for (unsigned i = 0; i != NumOps; ++i) {
if (TID.getOperandConstraint(i+NumRes, TOI::TIED_TO) != -1) {
SDNode *DU = SU->Node->getOperand(i).Val;
- if ((*SUnitMap).find(DU) != (*SUnitMap).end() &&
- Op == (*SUnitMap)[DU][SU->InstanceNo])
+ if (DU->getNodeId() != -1 &&
+ Op->OrigNode == &(*SUnits)[DU->getNodeId()])
return true;
}
}
}
/// canClobberPhysRegDefs - True if SU would clobber one of SuccSU's
-/// physical register def.
+/// physical register defs.
static bool canClobberPhysRegDefs(SUnit *SuccSU, SUnit *SU,
const TargetInstrInfo *TII,
const TargetRegisterInfo *TRI) {
SDNode *N = SuccSU->Node;
unsigned NumDefs = TII->get(N->getTargetOpcode()).getNumDefs();
const unsigned *ImpDefs = TII->get(N->getTargetOpcode()).getImplicitDefs();
- if (!ImpDefs)
- return false;
+ assert(ImpDefs && "Caller should check hasPhysRegDefs");
const unsigned *SUImpDefs =
TII->get(SU->Node->getTargetOpcode()).getImplicitDefs();
if (!SUImpDefs)
return false;
for (unsigned i = NumDefs, e = N->getNumValues(); i != e; ++i) {
- MVT::ValueType VT = N->getValueType(i);
+ MVT VT = N->getValueType(i);
if (VT == MVT::Flag || VT == MVT::Other)
continue;
unsigned Reg = ImpDefs[i - NumDefs];
/// one that has a CopyToReg use (more likely to be a loop induction update).
/// If both are two-address, but one is commutable while the other is not
/// commutable, favor the one that's not commutable.
-template<class SF>
-void BURegReductionPriorityQueue<SF>::AddPseudoTwoAddrDeps() {
+void BURegReductionPriorityQueue::AddPseudoTwoAddrDeps() {
for (unsigned i = 0, e = SUnits->size(); i != e; ++i) {
SUnit *SU = (SUnit *)&((*SUnits)[i]);
if (!SU->isTwoAddress)
for (unsigned j = 0; j != NumOps; ++j) {
if (TID.getOperandConstraint(j+NumRes, TOI::TIED_TO) != -1) {
SDNode *DU = SU->Node->getOperand(j).Val;
- if ((*SUnitMap).find(DU) == (*SUnitMap).end())
+ if (DU->getNodeId() == -1)
continue;
- SUnit *DUSU = (*SUnitMap)[DU][SU->InstanceNo];
+ const SUnit *DUSU = &(*SUnits)[DU->getNodeId()];
if (!DUSU) continue;
- for (SUnit::succ_iterator I = DUSU->Succs.begin(),E = DUSU->Succs.end();
- I != E; ++I) {
+ for (SUnit::const_succ_iterator I = DUSU->Succs.begin(),
+ E = DUSU->Succs.end(); I != E; ++I) {
if (I->isCtrl) continue;
SUnit *SuccSU = I->Dep;
if (SuccSU == SU)
if ((!canClobber(SuccSU, DUSU) ||
(hasCopyToRegUse(SU) && !hasCopyToRegUse(SuccSU)) ||
(!SU->isCommutable && SuccSU->isCommutable)) &&
- !isReachable(SuccSU, SU)) {
+ !scheduleDAG->IsReachable(SuccSU, SU)) {
DOUT << "Adding an edge from SU # " << SU->NodeNum
<< " to SU #" << SuccSU->NodeNum << "\n";
- SU->addPred(SuccSU, true, true);
+ scheduleDAG->AddPred(SU, SuccSU, true, true);
}
}
}
/// CalcNodeSethiUllmanNumber - Priority is the Sethi Ullman number.
/// Smaller number is the higher priority.
-template<class SF>
-unsigned BURegReductionPriorityQueue<SF>::
+unsigned BURegReductionPriorityQueue::
CalcNodeSethiUllmanNumber(const SUnit *SU) {
unsigned &SethiUllmanNumber = SethiUllmanNumbers[SU->NodeNum];
if (SethiUllmanNumber != 0)
/// CalculateSethiUllmanNumbers - Calculate Sethi-Ullman numbers of all
/// scheduling units.
-template<class SF>
-void BURegReductionPriorityQueue<SF>::CalculateSethiUllmanNumbers() {
+void BURegReductionPriorityQueue::CalculateSethiUllmanNumbers() {
SethiUllmanNumbers.assign(SUnits->size(), 0);
for (unsigned i = 0, e = SUnits->size(); i != e; ++i)
CalcNodeSethiUllmanNumber(&(*SUnits)[i]);
}
-static unsigned SumOfUnscheduledPredsOfSuccs(const SUnit *SU) {
+/// LimitedSumOfUnscheduledPredsOfSuccs - Compute the sum of the unscheduled
+/// predecessors of the successors of the SUnit SU. Stop when the provided
+/// limit is exceeded.
+static unsigned LimitedSumOfUnscheduledPredsOfSuccs(const SUnit *SU,
+ unsigned Limit) {
unsigned Sum = 0;
for (SUnit::const_succ_iterator I = SU->Succs.begin(), E = SU->Succs.end();
I != E; ++I) {
EE = SuccSU->Preds.end(); II != EE; ++II) {
SUnit *PredSU = II->Dep;
if (!PredSU->isScheduled)
- ++Sum;
+ if (++Sum > Limit)
+ return Sum;
}
}
-
return Sum;
}
bool RIsTarget = right->Node && right->Node->isTargetOpcode();
bool LIsFloater = LIsTarget && left->NumPreds == 0;
bool RIsFloater = RIsTarget && right->NumPreds == 0;
- unsigned LBonus = (SumOfUnscheduledPredsOfSuccs(left) == 1) ? 2 : 0;
- unsigned RBonus = (SumOfUnscheduledPredsOfSuccs(right) == 1) ? 2 : 0;
+ unsigned LBonus = (LimitedSumOfUnscheduledPredsOfSuccs(left,1) == 1) ? 2 : 0;
+ unsigned RBonus = (LimitedSumOfUnscheduledPredsOfSuccs(right,1) == 1) ? 2 : 0;
if (left->NumSuccs == 0 && right->NumSuccs != 0)
return false;
if (left->CycleBound != right->CycleBound)
return left->CycleBound > right->CycleBound;
- // FIXME: No strict ordering.
- return false;
+ assert(left->NodeQueueId && right->NodeQueueId &&
+ "NodeQueueId cannot be zero");
+ return (left->NodeQueueId > right->NodeQueueId);
}
/// CalcNodeSethiUllmanNumber - Priority is the Sethi Ullman number.
/// Smaller number is the higher priority.
-template<class SF>
-unsigned TDRegReductionPriorityQueue<SF>::
+unsigned TDRegReductionPriorityQueue::
CalcNodeSethiUllmanNumber(const SUnit *SU) {
unsigned &SethiUllmanNumber = SethiUllmanNumbers[SU->NodeNum];
if (SethiUllmanNumber != 0)
/// CalculateSethiUllmanNumbers - Calculate Sethi-Ullman numbers of all
/// scheduling units.
-template<class SF>
-void TDRegReductionPriorityQueue<SF>::CalculateSethiUllmanNumbers() {
+void TDRegReductionPriorityQueue::CalculateSethiUllmanNumbers() {
SethiUllmanNumbers.assign(SUnits->size(), 0);
for (unsigned i = 0, e = SUnits->size(); i != e; ++i)
MachineBasicBlock *BB) {
const TargetInstrInfo *TII = DAG->getTarget().getInstrInfo();
const TargetRegisterInfo *TRI = DAG->getTarget().getRegisterInfo();
- return new ScheduleDAGRRList(*DAG, BB, DAG->getTarget(), true,
- new BURegReductionPriorityQueue<bu_ls_rr_sort>(TII, TRI));
+
+ BURegReductionPriorityQueue *priorityQueue =
+ new BURegReductionPriorityQueue(TII, TRI);
+
+ ScheduleDAGRRList * scheduleDAG =
+ new ScheduleDAGRRList(*DAG, BB, DAG->getTarget(), true, priorityQueue);
+ priorityQueue->setScheduleDAG(scheduleDAG);
+ return scheduleDAG;
}
llvm::ScheduleDAG* llvm::createTDRRListDAGScheduler(SelectionDAGISel *IS,
SelectionDAG *DAG,
MachineBasicBlock *BB) {
return new ScheduleDAGRRList(*DAG, BB, DAG->getTarget(), false,
- new TDRegReductionPriorityQueue<td_ls_rr_sort>());
+ new TDRegReductionPriorityQueue());
}