#define DEBUG_TYPE "pre-RA-sched"
#include "llvm/CodeGen/ScheduleDAG.h"
#include "llvm/CodeGen/ScheduleHazardRecognizer.h"
+#include "llvm/CodeGen/SelectionDAGNodes.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetInstrInfo.h"
#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include <climits>
using namespace llvm;
+#ifndef NDEBUG
+static cl::opt<bool> StressSchedOpt(
+ "stress-sched", cl::Hidden, cl::init(false),
+ cl::desc("Stress test instruction scheduling"));
+#endif
+
+void SchedulingPriorityQueue::anchor() { }
+
ScheduleDAG::ScheduleDAG(MachineFunction &mf)
: TM(mf.getTarget()),
TII(TM.getInstrInfo()),
TRI(TM.getRegisterInfo()),
- TLI(TM.getTargetLowering()),
MF(mf), MRI(mf.getRegInfo()),
- ConstPool(MF.getConstantPool()),
EntrySU(), ExitSU() {
+#ifndef NDEBUG
+ StressSched = StressSchedOpt;
+#endif
}
ScheduleDAG::~ScheduleDAG() {}
-/// dump - dump the schedule.
-void ScheduleDAG::dumpSchedule() const {
- for (unsigned i = 0, e = Sequence.size(); i != e; i++) {
- if (SUnit *SU = Sequence[i])
- SU->dump(this);
- else
- dbgs() << "**** NOOP ****\n";
- }
-}
-
-
-/// Run - perform scheduling.
-///
-void ScheduleDAG::Run(MachineBasicBlock *bb,
- MachineBasicBlock::iterator insertPos) {
- BB = bb;
- InsertPos = insertPos;
-
+/// Clear the DAG state (e.g. between scheduling regions).
+void ScheduleDAG::clearDAG() {
SUnits.clear();
- Sequence.clear();
EntrySU = SUnit();
ExitSU = SUnit();
+}
- Schedule();
-
- DEBUG({
- dbgs() << "*** Final schedule ***\n";
- dumpSchedule();
- dbgs() << '\n';
- });
+/// getInstrDesc helper to handle SDNodes.
+const MCInstrDesc *ScheduleDAG::getNodeDesc(const SDNode *Node) const {
+ if (!Node || !Node->isMachineOpcode()) return NULL;
+ return &TII->get(Node->getMachineOpcode());
}
/// addPred - This adds the specified edge as a pred of the current node if
/// not already. It also adds the current node as a successor of the
/// specified node.
-void SUnit::addPred(const SDep &D) {
+bool SUnit::addPred(const SDep &D) {
// If this node already has this depenence, don't add a redundant one.
for (SmallVector<SDep, 4>::const_iterator I = Preds.begin(), E = Preds.end();
I != E; ++I)
if (*I == D)
- return;
+ return false;
// Now add a corresponding succ to N.
SDep P = D;
P.setSUnit(this);
this->setDepthDirty();
N->setHeightDirty();
}
+ return true;
}
/// removePred - This removes the specified edge as a pred of the current
break;
}
assert(FoundSucc && "Mismatching preds / succs lists!");
+ (void)FoundSucc;
Preds.erase(I);
// Update the bookkeeping.
if (P.getKind() == SDep::Data) {
dbgs() << " # preds left : " << NumPredsLeft << "\n";
dbgs() << " # succs left : " << NumSuccsLeft << "\n";
+ dbgs() << " # rdefs left : " << NumRegDefsLeft << "\n";
dbgs() << " Latency : " << Latency << "\n";
dbgs() << " Depth : " << Depth << "\n";
dbgs() << " Height : " << Height << "\n";
case SDep::Output: dbgs() << "out "; break;
case SDep::Order: dbgs() << "ch "; break;
}
- dbgs() << "#";
- dbgs() << I->getSUnit() << " - SU(" << I->getSUnit()->NodeNum << ")";
+ dbgs() << "SU(" << I->getSUnit()->NodeNum << ")";
if (I->isArtificial())
dbgs() << " *";
dbgs() << ": Latency=" << I->getLatency();
+ if (I->isAssignedRegDep())
+ dbgs() << " Reg=" << PrintReg(I->getReg(), G->TRI);
dbgs() << "\n";
}
}
case SDep::Output: dbgs() << "out "; break;
case SDep::Order: dbgs() << "ch "; break;
}
- dbgs() << "#";
- dbgs() << I->getSUnit() << " - SU(" << I->getSUnit()->NodeNum << ")";
+ dbgs() << "SU(" << I->getSUnit()->NodeNum << ")";
if (I->isArtificial())
dbgs() << " *";
dbgs() << ": Latency=" << I->getLatency();
}
#ifndef NDEBUG
-/// VerifySchedule - Verify that all SUnits were scheduled and that
-/// their state is consistent.
+/// VerifyScheduledDAG - Verify that all SUnits were scheduled and that
+/// their state is consistent. Return the number of scheduled nodes.
///
-void ScheduleDAG::VerifySchedule(bool isBottomUp) {
+unsigned ScheduleDAG::VerifyScheduledDAG(bool isBottomUp) {
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) {
}
}
}
- 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!");
+ return SUnits.size() - DeadNodes;
}
#endif
-/// InitDAGTopologicalSorting - create the initial topological
+/// InitDAGTopologicalSorting - create the initial topological
/// ordering from the DAG to be scheduled.
///
-/// The idea of the algorithm is taken from
+/// 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
+/// 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:
+/// 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,
+/// 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
+/// 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
// Collect leaf nodes.
WorkList.push_back(SU);
}
- }
+ }
int Id = DAGSize;
while (!WorkList.empty()) {
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->getSUnit()->NodeNum] &&
+ assert(Node2Index[SU->NodeNum] > Node2Index[I->getSUnit()->NodeNum] &&
"Wrong topological sorting");
}
}
#endif
}
-/// AddPred - Updates the topological ordering to accomodate an edge
+/// AddPred - Updates the topological ordering to accommodate an edge
/// to be added from SUnit X to SUnit Y.
void ScheduleDAGTopologicalSort::AddPred(SUnit *Y, SUnit *X) {
int UpperBound, LowerBound;
}
}
-/// RemovePred - Updates the topological ordering to accomodate an
+/// RemovePred - Updates the topological ordering to accommodate an
/// an edge to be removed from the specified node N from the predecessors
/// of the current node M.
void ScheduleDAGTopologicalSort::RemovePred(SUnit *M, SUnit *N) {
/// all nodes affected by the edge insertion. These nodes will later get new
/// topological indexes by means of the Shift method.
void ScheduleDAGTopologicalSort::DFS(const SUnit *SU, int UpperBound,
- bool& HasLoop) {
+ bool &HasLoop) {
std::vector<const SUnit*> WorkList;
- WorkList.reserve(SUnits.size());
+ WorkList.reserve(SUnits.size());
WorkList.push_back(SU);
do {
for (int I = SU->Succs.size()-1; I >= 0; --I) {
int s = SU->Succs[I].getSUnit()->NodeNum;
if (Node2Index[s] == UpperBound) {
- HasLoop = true;
+ 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].getSUnit());
- }
- }
+ }
+ }
} while (!WorkList.empty());
}
-/// Shift - Renumber the nodes so that the topological ordering is
+/// Shift - Renumber the nodes so that the topological ordering is
/// preserved.
-void ScheduleDAGTopologicalSort::Shift(BitVector& Visited, int LowerBound,
+void ScheduleDAGTopologicalSort::Shift(BitVector& Visited, int LowerBound,
int UpperBound) {
std::vector<int> L;
int shift = 0;
// Is Ord(TargetSU) < Ord(SU) ?
if (LowerBound < UpperBound) {
Visited.reset();
- // There may be a path from TargetSU to SU. Check for it.
+ // There may be a path from TargetSU to SU. Check for it.
DFS(TargetSU, UpperBound, HasLoop);
}
return HasLoop;
Index2Node[index] = n;
}
-ScheduleDAGTopologicalSort::ScheduleDAGTopologicalSort(
- std::vector<SUnit> &sunits)
- : SUnits(sunits) {}
+ScheduleDAGTopologicalSort::
+ScheduleDAGTopologicalSort(std::vector<SUnit> &sunits) : SUnits(sunits) {}
ScheduleHazardRecognizer::~ScheduleHazardRecognizer() {}