1 //===---- ScheduleDAG.cpp - Implement the ScheduleDAG class ---------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This implements the ScheduleDAG class, which is a base class used by 11 // scheduling implementation classes. 12 // 13 //===----------------------------------------------------------------------===// 14 15 #include "llvm/CodeGen/ScheduleDAG.h" 16 #include "llvm/CodeGen/ScheduleHazardRecognizer.h" 17 #include "llvm/CodeGen/SelectionDAGNodes.h" 18 #include "llvm/Support/CommandLine.h" 19 #include "llvm/Support/Debug.h" 20 #include "llvm/Support/raw_ostream.h" 21 #include "llvm/Target/TargetInstrInfo.h" 22 #include "llvm/Target/TargetMachine.h" 23 #include "llvm/Target/TargetRegisterInfo.h" 24 #include "llvm/Target/TargetSubtargetInfo.h" 25 #include <climits> 26 using namespace llvm; 27 28 #define DEBUG_TYPE "pre-RA-sched" 29 30 #ifndef NDEBUG 31 static cl::opt<bool> StressSchedOpt( 32 "stress-sched", cl::Hidden, cl::init(false), 33 cl::desc("Stress test instruction scheduling")); 34 #endif 35 36 void SchedulingPriorityQueue::anchor() { } 37 38 ScheduleDAG::ScheduleDAG(MachineFunction &mf) 39 : TM(mf.getTarget()), TII(mf.getSubtarget().getInstrInfo()), 40 TRI(mf.getSubtarget().getRegisterInfo()), MF(mf), 41 MRI(mf.getRegInfo()), EntrySU(), ExitSU() { 42 #ifndef NDEBUG 43 StressSched = StressSchedOpt; 44 #endif 45 } 46 47 ScheduleDAG::~ScheduleDAG() {} 48 49 /// Clear the DAG state (e.g. between scheduling regions). 50 void ScheduleDAG::clearDAG() { 51 SUnits.clear(); 52 EntrySU = SUnit(); 53 ExitSU = SUnit(); 54 } 55 56 /// getInstrDesc helper to handle SDNodes. 57 const MCInstrDesc *ScheduleDAG::getNodeDesc(const SDNode *Node) const { 58 if (!Node || !Node->isMachineOpcode()) return nullptr; 59 return &TII->get(Node->getMachineOpcode()); 60 } 61 62 /// addPred - This adds the specified edge as a pred of the current node if 63 /// not already. It also adds the current node as a successor of the 64 /// specified node. 65 bool SUnit::addPred(const SDep &D, bool Required) { 66 // If this node already has this dependence, don't add a redundant one. 67 for (SmallVectorImpl<SDep>::iterator I = Preds.begin(), E = Preds.end(); 68 I != E; ++I) { 69 // Zero-latency weak edges may be added purely for heuristic ordering. Don't 70 // add them if another kind of edge already exists. 71 if (!Required && I->getSUnit() == D.getSUnit()) 72 return false; 73 if (I->overlaps(D)) { 74 // Extend the latency if needed. Equivalent to removePred(I) + addPred(D). 75 if (I->getLatency() < D.getLatency()) { 76 SUnit *PredSU = I->getSUnit(); 77 // Find the corresponding successor in N. 78 SDep ForwardD = *I; 79 ForwardD.setSUnit(this); 80 for (SmallVectorImpl<SDep>::iterator II = PredSU->Succs.begin(), 81 EE = PredSU->Succs.end(); II != EE; ++II) { 82 if (*II == ForwardD) { 83 II->setLatency(D.getLatency()); 84 break; 85 } 86 } 87 I->setLatency(D.getLatency()); 88 } 89 return false; 90 } 91 } 92 // Now add a corresponding succ to N. 93 SDep P = D; 94 P.setSUnit(this); 95 SUnit *N = D.getSUnit(); 96 // Update the bookkeeping. 97 if (D.getKind() == SDep::Data) { 98 assert(NumPreds < UINT_MAX && "NumPreds will overflow!"); 99 assert(N->NumSuccs < UINT_MAX && "NumSuccs will overflow!"); 100 ++NumPreds; 101 ++N->NumSuccs; 102 } 103 if (!N->isScheduled) { 104 if (D.isWeak()) { 105 ++WeakPredsLeft; 106 } 107 else { 108 assert(NumPredsLeft < UINT_MAX && "NumPredsLeft will overflow!"); 109 ++NumPredsLeft; 110 } 111 } 112 if (!isScheduled) { 113 if (D.isWeak()) { 114 ++N->WeakSuccsLeft; 115 } 116 else { 117 assert(N->NumSuccsLeft < UINT_MAX && "NumSuccsLeft will overflow!"); 118 ++N->NumSuccsLeft; 119 } 120 } 121 Preds.push_back(D); 122 N->Succs.push_back(P); 123 if (P.getLatency() != 0) { 124 this->setDepthDirty(); 125 N->setHeightDirty(); 126 } 127 return true; 128 } 129 130 /// removePred - This removes the specified edge as a pred of the current 131 /// node if it exists. It also removes the current node as a successor of 132 /// the specified node. 133 void SUnit::removePred(const SDep &D) { 134 // Find the matching predecessor. 135 for (SmallVectorImpl<SDep>::iterator I = Preds.begin(), E = Preds.end(); 136 I != E; ++I) 137 if (*I == D) { 138 // Find the corresponding successor in N. 139 SDep P = D; 140 P.setSUnit(this); 141 SUnit *N = D.getSUnit(); 142 SmallVectorImpl<SDep>::iterator Succ = std::find(N->Succs.begin(), 143 N->Succs.end(), P); 144 assert(Succ != N->Succs.end() && "Mismatching preds / succs lists!"); 145 N->Succs.erase(Succ); 146 Preds.erase(I); 147 // Update the bookkeeping. 148 if (P.getKind() == SDep::Data) { 149 assert(NumPreds > 0 && "NumPreds will underflow!"); 150 assert(N->NumSuccs > 0 && "NumSuccs will underflow!"); 151 --NumPreds; 152 --N->NumSuccs; 153 } 154 if (!N->isScheduled) { 155 if (D.isWeak()) 156 --WeakPredsLeft; 157 else { 158 assert(NumPredsLeft > 0 && "NumPredsLeft will underflow!"); 159 --NumPredsLeft; 160 } 161 } 162 if (!isScheduled) { 163 if (D.isWeak()) 164 --N->WeakSuccsLeft; 165 else { 166 assert(N->NumSuccsLeft > 0 && "NumSuccsLeft will underflow!"); 167 --N->NumSuccsLeft; 168 } 169 } 170 if (P.getLatency() != 0) { 171 this->setDepthDirty(); 172 N->setHeightDirty(); 173 } 174 return; 175 } 176 } 177 178 void SUnit::setDepthDirty() { 179 if (!isDepthCurrent) return; 180 SmallVector<SUnit*, 8> WorkList; 181 WorkList.push_back(this); 182 do { 183 SUnit *SU = WorkList.pop_back_val(); 184 SU->isDepthCurrent = false; 185 for (SUnit::const_succ_iterator I = SU->Succs.begin(), 186 E = SU->Succs.end(); I != E; ++I) { 187 SUnit *SuccSU = I->getSUnit(); 188 if (SuccSU->isDepthCurrent) 189 WorkList.push_back(SuccSU); 190 } 191 } while (!WorkList.empty()); 192 } 193 194 void SUnit::setHeightDirty() { 195 if (!isHeightCurrent) return; 196 SmallVector<SUnit*, 8> WorkList; 197 WorkList.push_back(this); 198 do { 199 SUnit *SU = WorkList.pop_back_val(); 200 SU->isHeightCurrent = false; 201 for (SUnit::const_pred_iterator I = SU->Preds.begin(), 202 E = SU->Preds.end(); I != E; ++I) { 203 SUnit *PredSU = I->getSUnit(); 204 if (PredSU->isHeightCurrent) 205 WorkList.push_back(PredSU); 206 } 207 } while (!WorkList.empty()); 208 } 209 210 /// setDepthToAtLeast - Update this node's successors to reflect the 211 /// fact that this node's depth just increased. 212 /// 213 void SUnit::setDepthToAtLeast(unsigned NewDepth) { 214 if (NewDepth <= getDepth()) 215 return; 216 setDepthDirty(); 217 Depth = NewDepth; 218 isDepthCurrent = true; 219 } 220 221 /// setHeightToAtLeast - Update this node's predecessors to reflect the 222 /// fact that this node's height just increased. 223 /// 224 void SUnit::setHeightToAtLeast(unsigned NewHeight) { 225 if (NewHeight <= getHeight()) 226 return; 227 setHeightDirty(); 228 Height = NewHeight; 229 isHeightCurrent = true; 230 } 231 232 /// ComputeDepth - Calculate the maximal path from the node to the exit. 233 /// 234 void SUnit::ComputeDepth() { 235 SmallVector<SUnit*, 8> WorkList; 236 WorkList.push_back(this); 237 do { 238 SUnit *Cur = WorkList.back(); 239 240 bool Done = true; 241 unsigned MaxPredDepth = 0; 242 for (SUnit::const_pred_iterator I = Cur->Preds.begin(), 243 E = Cur->Preds.end(); I != E; ++I) { 244 SUnit *PredSU = I->getSUnit(); 245 if (PredSU->isDepthCurrent) 246 MaxPredDepth = std::max(MaxPredDepth, 247 PredSU->Depth + I->getLatency()); 248 else { 249 Done = false; 250 WorkList.push_back(PredSU); 251 } 252 } 253 254 if (Done) { 255 WorkList.pop_back(); 256 if (MaxPredDepth != Cur->Depth) { 257 Cur->setDepthDirty(); 258 Cur->Depth = MaxPredDepth; 259 } 260 Cur->isDepthCurrent = true; 261 } 262 } while (!WorkList.empty()); 263 } 264 265 /// ComputeHeight - Calculate the maximal path from the node to the entry. 266 /// 267 void SUnit::ComputeHeight() { 268 SmallVector<SUnit*, 8> WorkList; 269 WorkList.push_back(this); 270 do { 271 SUnit *Cur = WorkList.back(); 272 273 bool Done = true; 274 unsigned MaxSuccHeight = 0; 275 for (SUnit::const_succ_iterator I = Cur->Succs.begin(), 276 E = Cur->Succs.end(); I != E; ++I) { 277 SUnit *SuccSU = I->getSUnit(); 278 if (SuccSU->isHeightCurrent) 279 MaxSuccHeight = std::max(MaxSuccHeight, 280 SuccSU->Height + I->getLatency()); 281 else { 282 Done = false; 283 WorkList.push_back(SuccSU); 284 } 285 } 286 287 if (Done) { 288 WorkList.pop_back(); 289 if (MaxSuccHeight != Cur->Height) { 290 Cur->setHeightDirty(); 291 Cur->Height = MaxSuccHeight; 292 } 293 Cur->isHeightCurrent = true; 294 } 295 } while (!WorkList.empty()); 296 } 297 298 void SUnit::biasCriticalPath() { 299 if (NumPreds < 2) 300 return; 301 302 SUnit::pred_iterator BestI = Preds.begin(); 303 unsigned MaxDepth = BestI->getSUnit()->getDepth(); 304 for (SUnit::pred_iterator I = std::next(BestI), E = Preds.end(); I != E; 305 ++I) { 306 if (I->getKind() == SDep::Data && I->getSUnit()->getDepth() > MaxDepth) 307 BestI = I; 308 } 309 if (BestI != Preds.begin()) 310 std::swap(*Preds.begin(), *BestI); 311 } 312 313 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) 314 /// SUnit - Scheduling unit. It's an wrapper around either a single SDNode or 315 /// a group of nodes flagged together. 316 void SUnit::dump(const ScheduleDAG *G) const { 317 dbgs() << "SU(" << NodeNum << "): "; 318 G->dumpNode(this); 319 } 320 321 void SUnit::dumpAll(const ScheduleDAG *G) const { 322 dump(G); 323 324 dbgs() << " # preds left : " << NumPredsLeft << "\n"; 325 dbgs() << " # succs left : " << NumSuccsLeft << "\n"; 326 if (WeakPredsLeft) 327 dbgs() << " # weak preds left : " << WeakPredsLeft << "\n"; 328 if (WeakSuccsLeft) 329 dbgs() << " # weak succs left : " << WeakSuccsLeft << "\n"; 330 dbgs() << " # rdefs left : " << NumRegDefsLeft << "\n"; 331 dbgs() << " Latency : " << Latency << "\n"; 332 dbgs() << " Depth : " << getDepth() << "\n"; 333 dbgs() << " Height : " << getHeight() << "\n"; 334 335 if (Preds.size() != 0) { 336 dbgs() << " Predecessors:\n"; 337 for (SUnit::const_succ_iterator I = Preds.begin(), E = Preds.end(); 338 I != E; ++I) { 339 dbgs() << " "; 340 switch (I->getKind()) { 341 case SDep::Data: dbgs() << "val "; break; 342 case SDep::Anti: dbgs() << "anti"; break; 343 case SDep::Output: dbgs() << "out "; break; 344 case SDep::Order: dbgs() << "ch "; break; 345 } 346 dbgs() << "SU(" << I->getSUnit()->NodeNum << ")"; 347 if (I->isArtificial()) 348 dbgs() << " *"; 349 dbgs() << ": Latency=" << I->getLatency(); 350 if (I->isAssignedRegDep()) 351 dbgs() << " Reg=" << PrintReg(I->getReg(), G->TRI); 352 dbgs() << "\n"; 353 } 354 } 355 if (Succs.size() != 0) { 356 dbgs() << " Successors:\n"; 357 for (SUnit::const_succ_iterator I = Succs.begin(), E = Succs.end(); 358 I != E; ++I) { 359 dbgs() << " "; 360 switch (I->getKind()) { 361 case SDep::Data: dbgs() << "val "; break; 362 case SDep::Anti: dbgs() << "anti"; break; 363 case SDep::Output: dbgs() << "out "; break; 364 case SDep::Order: dbgs() << "ch "; break; 365 } 366 dbgs() << "SU(" << I->getSUnit()->NodeNum << ")"; 367 if (I->isArtificial()) 368 dbgs() << " *"; 369 dbgs() << ": Latency=" << I->getLatency(); 370 if (I->isAssignedRegDep()) 371 dbgs() << " Reg=" << PrintReg(I->getReg(), G->TRI); 372 dbgs() << "\n"; 373 } 374 } 375 } 376 #endif 377 378 #ifndef NDEBUG 379 /// VerifyScheduledDAG - Verify that all SUnits were scheduled and that 380 /// their state is consistent. Return the number of scheduled nodes. 381 /// 382 unsigned ScheduleDAG::VerifyScheduledDAG(bool isBottomUp) { 383 bool AnyNotSched = false; 384 unsigned DeadNodes = 0; 385 for (unsigned i = 0, e = SUnits.size(); i != e; ++i) { 386 if (!SUnits[i].isScheduled) { 387 if (SUnits[i].NumPreds == 0 && SUnits[i].NumSuccs == 0) { 388 ++DeadNodes; 389 continue; 390 } 391 if (!AnyNotSched) 392 dbgs() << "*** Scheduling failed! ***\n"; 393 SUnits[i].dump(this); 394 dbgs() << "has not been scheduled!\n"; 395 AnyNotSched = true; 396 } 397 if (SUnits[i].isScheduled && 398 (isBottomUp ? SUnits[i].getHeight() : SUnits[i].getDepth()) > 399 unsigned(INT_MAX)) { 400 if (!AnyNotSched) 401 dbgs() << "*** Scheduling failed! ***\n"; 402 SUnits[i].dump(this); 403 dbgs() << "has an unexpected " 404 << (isBottomUp ? "Height" : "Depth") << " value!\n"; 405 AnyNotSched = true; 406 } 407 if (isBottomUp) { 408 if (SUnits[i].NumSuccsLeft != 0) { 409 if (!AnyNotSched) 410 dbgs() << "*** Scheduling failed! ***\n"; 411 SUnits[i].dump(this); 412 dbgs() << "has successors left!\n"; 413 AnyNotSched = true; 414 } 415 } else { 416 if (SUnits[i].NumPredsLeft != 0) { 417 if (!AnyNotSched) 418 dbgs() << "*** Scheduling failed! ***\n"; 419 SUnits[i].dump(this); 420 dbgs() << "has predecessors left!\n"; 421 AnyNotSched = true; 422 } 423 } 424 } 425 assert(!AnyNotSched); 426 return SUnits.size() - DeadNodes; 427 } 428 #endif 429 430 /// InitDAGTopologicalSorting - create the initial topological 431 /// ordering from the DAG to be scheduled. 432 /// 433 /// The idea of the algorithm is taken from 434 /// "Online algorithms for managing the topological order of 435 /// a directed acyclic graph" by David J. Pearce and Paul H.J. Kelly 436 /// This is the MNR algorithm, which was first introduced by 437 /// A. Marchetti-Spaccamela, U. Nanni and H. Rohnert in 438 /// "Maintaining a topological order under edge insertions". 439 /// 440 /// Short description of the algorithm: 441 /// 442 /// Topological ordering, ord, of a DAG maps each node to a topological 443 /// index so that for all edges X->Y it is the case that ord(X) < ord(Y). 444 /// 445 /// This means that if there is a path from the node X to the node Z, 446 /// then ord(X) < ord(Z). 447 /// 448 /// This property can be used to check for reachability of nodes: 449 /// if Z is reachable from X, then an insertion of the edge Z->X would 450 /// create a cycle. 451 /// 452 /// The algorithm first computes a topological ordering for the DAG by 453 /// initializing the Index2Node and Node2Index arrays and then tries to keep 454 /// the ordering up-to-date after edge insertions by reordering the DAG. 455 /// 456 /// On insertion of the edge X->Y, the algorithm first marks by calling DFS 457 /// the nodes reachable from Y, and then shifts them using Shift to lie 458 /// immediately after X in Index2Node. 459 void ScheduleDAGTopologicalSort::InitDAGTopologicalSorting() { 460 unsigned DAGSize = SUnits.size(); 461 std::vector<SUnit*> WorkList; 462 WorkList.reserve(DAGSize); 463 464 Index2Node.resize(DAGSize); 465 Node2Index.resize(DAGSize); 466 467 // Initialize the data structures. 468 if (ExitSU) 469 WorkList.push_back(ExitSU); 470 for (unsigned i = 0, e = DAGSize; i != e; ++i) { 471 SUnit *SU = &SUnits[i]; 472 int NodeNum = SU->NodeNum; 473 unsigned Degree = SU->Succs.size(); 474 // Temporarily use the Node2Index array as scratch space for degree counts. 475 Node2Index[NodeNum] = Degree; 476 477 // Is it a node without dependencies? 478 if (Degree == 0) { 479 assert(SU->Succs.empty() && "SUnit should have no successors"); 480 // Collect leaf nodes. 481 WorkList.push_back(SU); 482 } 483 } 484 485 int Id = DAGSize; 486 while (!WorkList.empty()) { 487 SUnit *SU = WorkList.back(); 488 WorkList.pop_back(); 489 if (SU->NodeNum < DAGSize) 490 Allocate(SU->NodeNum, --Id); 491 for (SUnit::const_pred_iterator I = SU->Preds.begin(), E = SU->Preds.end(); 492 I != E; ++I) { 493 SUnit *SU = I->getSUnit(); 494 if (SU->NodeNum < DAGSize && !--Node2Index[SU->NodeNum]) 495 // If all dependencies of the node are processed already, 496 // then the node can be computed now. 497 WorkList.push_back(SU); 498 } 499 } 500 501 Visited.resize(DAGSize); 502 503 #ifndef NDEBUG 504 // Check correctness of the ordering 505 for (unsigned i = 0, e = DAGSize; i != e; ++i) { 506 SUnit *SU = &SUnits[i]; 507 for (SUnit::const_pred_iterator I = SU->Preds.begin(), E = SU->Preds.end(); 508 I != E; ++I) { 509 assert(Node2Index[SU->NodeNum] > Node2Index[I->getSUnit()->NodeNum] && 510 "Wrong topological sorting"); 511 } 512 } 513 #endif 514 } 515 516 /// AddPred - Updates the topological ordering to accommodate an edge 517 /// to be added from SUnit X to SUnit Y. 518 void ScheduleDAGTopologicalSort::AddPred(SUnit *Y, SUnit *X) { 519 int UpperBound, LowerBound; 520 LowerBound = Node2Index[Y->NodeNum]; 521 UpperBound = Node2Index[X->NodeNum]; 522 bool HasLoop = false; 523 // Is Ord(X) < Ord(Y) ? 524 if (LowerBound < UpperBound) { 525 // Update the topological order. 526 Visited.reset(); 527 DFS(Y, UpperBound, HasLoop); 528 assert(!HasLoop && "Inserted edge creates a loop!"); 529 // Recompute topological indexes. 530 Shift(Visited, LowerBound, UpperBound); 531 } 532 } 533 534 /// RemovePred - Updates the topological ordering to accommodate an 535 /// an edge to be removed from the specified node N from the predecessors 536 /// of the current node M. 537 void ScheduleDAGTopologicalSort::RemovePred(SUnit *M, SUnit *N) { 538 // InitDAGTopologicalSorting(); 539 } 540 541 /// DFS - Make a DFS traversal to mark all nodes reachable from SU and mark 542 /// all nodes affected by the edge insertion. These nodes will later get new 543 /// topological indexes by means of the Shift method. 544 void ScheduleDAGTopologicalSort::DFS(const SUnit *SU, int UpperBound, 545 bool &HasLoop) { 546 std::vector<const SUnit*> WorkList; 547 WorkList.reserve(SUnits.size()); 548 549 WorkList.push_back(SU); 550 do { 551 SU = WorkList.back(); 552 WorkList.pop_back(); 553 Visited.set(SU->NodeNum); 554 for (int I = SU->Succs.size()-1; I >= 0; --I) { 555 unsigned s = SU->Succs[I].getSUnit()->NodeNum; 556 // Edges to non-SUnits are allowed but ignored (e.g. ExitSU). 557 if (s >= Node2Index.size()) 558 continue; 559 if (Node2Index[s] == UpperBound) { 560 HasLoop = true; 561 return; 562 } 563 // Visit successors if not already and in affected region. 564 if (!Visited.test(s) && Node2Index[s] < UpperBound) { 565 WorkList.push_back(SU->Succs[I].getSUnit()); 566 } 567 } 568 } while (!WorkList.empty()); 569 } 570 571 /// Shift - Renumber the nodes so that the topological ordering is 572 /// preserved. 573 void ScheduleDAGTopologicalSort::Shift(BitVector& Visited, int LowerBound, 574 int UpperBound) { 575 std::vector<int> L; 576 int shift = 0; 577 int i; 578 579 for (i = LowerBound; i <= UpperBound; ++i) { 580 // w is node at topological index i. 581 int w = Index2Node[i]; 582 if (Visited.test(w)) { 583 // Unmark. 584 Visited.reset(w); 585 L.push_back(w); 586 shift = shift + 1; 587 } else { 588 Allocate(w, i - shift); 589 } 590 } 591 592 for (unsigned j = 0; j < L.size(); ++j) { 593 Allocate(L[j], i - shift); 594 i = i + 1; 595 } 596 } 597 598 599 /// WillCreateCycle - Returns true if adding an edge to TargetSU from SU will 600 /// create a cycle. If so, it is not safe to call AddPred(TargetSU, SU). 601 bool ScheduleDAGTopologicalSort::WillCreateCycle(SUnit *TargetSU, SUnit *SU) { 602 // Is SU reachable from TargetSU via successor edges? 603 if (IsReachable(SU, TargetSU)) 604 return true; 605 for (SUnit::pred_iterator 606 I = TargetSU->Preds.begin(), E = TargetSU->Preds.end(); I != E; ++I) 607 if (I->isAssignedRegDep() && 608 IsReachable(SU, I->getSUnit())) 609 return true; 610 return false; 611 } 612 613 /// IsReachable - Checks if SU is reachable from TargetSU. 614 bool ScheduleDAGTopologicalSort::IsReachable(const SUnit *SU, 615 const SUnit *TargetSU) { 616 // If insertion of the edge SU->TargetSU would create a cycle 617 // then there is a path from TargetSU to SU. 618 int UpperBound, LowerBound; 619 LowerBound = Node2Index[TargetSU->NodeNum]; 620 UpperBound = Node2Index[SU->NodeNum]; 621 bool HasLoop = false; 622 // Is Ord(TargetSU) < Ord(SU) ? 623 if (LowerBound < UpperBound) { 624 Visited.reset(); 625 // There may be a path from TargetSU to SU. Check for it. 626 DFS(TargetSU, UpperBound, HasLoop); 627 } 628 return HasLoop; 629 } 630 631 /// Allocate - assign the topological index to the node n. 632 void ScheduleDAGTopologicalSort::Allocate(int n, int index) { 633 Node2Index[n] = index; 634 Index2Node[index] = n; 635 } 636 637 ScheduleDAGTopologicalSort:: 638 ScheduleDAGTopologicalSort(std::vector<SUnit> &sunits, SUnit *exitsu) 639 : SUnits(sunits), ExitSU(exitsu) {} 640 641 ScheduleHazardRecognizer::~ScheduleHazardRecognizer() {} 642