MachineBasicBlock.h revision b5e8b8c8f762ae9a95f52a477440e426622d5446
1//===-- llvm/CodeGen/MachineBasicBlock.h ------------------------*- C++ -*-===// 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// Collect the sequence of machine instructions for a basic block. 11// 12//===----------------------------------------------------------------------===// 13 14#ifndef LLVM_CODEGEN_MACHINEBASICBLOCK_H 15#define LLVM_CODEGEN_MACHINEBASICBLOCK_H 16 17#include "llvm/CodeGen/MachineInstr.h" 18#include "llvm/ADT/GraphTraits.h" 19#include "llvm/Support/DataTypes.h" 20#include <functional> 21 22namespace llvm { 23 24class Pass; 25class BasicBlock; 26class MachineFunction; 27class MCSymbol; 28class SlotIndexes; 29class StringRef; 30class raw_ostream; 31class MachineBranchProbabilityInfo; 32 33template <> 34struct ilist_traits<MachineInstr> : public ilist_default_traits<MachineInstr> { 35private: 36 mutable ilist_half_node<MachineInstr> Sentinel; 37 38 // this is only set by the MachineBasicBlock owning the LiveList 39 friend class MachineBasicBlock; 40 MachineBasicBlock* Parent; 41 42public: 43 MachineInstr *createSentinel() const { 44 return static_cast<MachineInstr*>(&Sentinel); 45 } 46 void destroySentinel(MachineInstr *) const {} 47 48 MachineInstr *provideInitialHead() const { return createSentinel(); } 49 MachineInstr *ensureHead(MachineInstr*) const { return createSentinel(); } 50 static void noteHead(MachineInstr*, MachineInstr*) {} 51 52 void addNodeToList(MachineInstr* N); 53 void removeNodeFromList(MachineInstr* N); 54 void transferNodesFromList(ilist_traits &SrcTraits, 55 ilist_iterator<MachineInstr> first, 56 ilist_iterator<MachineInstr> last); 57 void deleteNode(MachineInstr *N); 58private: 59 void createNode(const MachineInstr &); 60}; 61 62class MachineBasicBlock : public ilist_node<MachineBasicBlock> { 63 typedef ilist<MachineInstr> Instructions; 64 Instructions Insts; 65 const BasicBlock *BB; 66 int Number; 67 MachineFunction *xParent; 68 69 /// Predecessors/Successors - Keep track of the predecessor / successor 70 /// basicblocks. 71 std::vector<MachineBasicBlock *> Predecessors; 72 std::vector<MachineBasicBlock *> Successors; 73 74 75 /// Weights - Keep track of the weights to the successors. This vector 76 /// has the same order as Successors, or it is empty if we don't use it 77 /// (disable optimization). 78 std::vector<uint32_t> Weights; 79 typedef std::vector<uint32_t>::iterator weight_iterator; 80 81 /// LiveIns - Keep track of the physical registers that are livein of 82 /// the basicblock. 83 std::vector<unsigned> LiveIns; 84 85 /// Alignment - Alignment of the basic block. Zero if the basic block does 86 /// not need to be aligned. 87 /// The alignment is specified as log2(bytes). 88 unsigned Alignment; 89 90 /// IsLandingPad - Indicate that this basic block is entered via an 91 /// exception handler. 92 bool IsLandingPad; 93 94 /// AddressTaken - Indicate that this basic block is potentially the 95 /// target of an indirect branch. 96 bool AddressTaken; 97 98 // Intrusive list support 99 MachineBasicBlock() {} 100 101 explicit MachineBasicBlock(MachineFunction &mf, const BasicBlock *bb); 102 103 ~MachineBasicBlock(); 104 105 // MachineBasicBlocks are allocated and owned by MachineFunction. 106 friend class MachineFunction; 107 108public: 109 /// getBasicBlock - Return the LLVM basic block that this instance 110 /// corresponded to originally. Note that this may be NULL if this instance 111 /// does not correspond directly to an LLVM basic block. 112 /// 113 const BasicBlock *getBasicBlock() const { return BB; } 114 115 /// getName - Return the name of the corresponding LLVM basic block, or 116 /// "(null)". 117 StringRef getName() const; 118 119 /// hasAddressTaken - Test whether this block is potentially the target 120 /// of an indirect branch. 121 bool hasAddressTaken() const { return AddressTaken; } 122 123 /// setHasAddressTaken - Set this block to reflect that it potentially 124 /// is the target of an indirect branch. 125 void setHasAddressTaken() { AddressTaken = true; } 126 127 /// getParent - Return the MachineFunction containing this basic block. 128 /// 129 const MachineFunction *getParent() const { return xParent; } 130 MachineFunction *getParent() { return xParent; } 131 132 133 /// bundle_iterator - MachineBasicBlock iterator that automatically skips over 134 /// MIs that are inside bundles (i.e. walk top level MIs only). 135 template<typename Ty, typename IterTy> 136 class bundle_iterator 137 : public std::iterator<std::bidirectional_iterator_tag, Ty, ptrdiff_t> { 138 IterTy MII; 139 140 public: 141 bundle_iterator(IterTy mii) : MII(mii) { 142 assert(!MII->isInsideBundle() && 143 "It's not legal to initialize bundle_iterator with a bundled MI"); 144 } 145 146 bundle_iterator(Ty &mi) : MII(mi) { 147 assert(!mi.isInsideBundle() && 148 "It's not legal to initialize bundle_iterator with a bundled MI"); 149 } 150 bundle_iterator(Ty *mi) : MII(mi) { 151 assert((!mi || !mi->isInsideBundle()) && 152 "It's not legal to initialize bundle_iterator with a bundled MI"); 153 } 154 bundle_iterator(const bundle_iterator &I) : MII(I.MII) {} 155 bundle_iterator() : MII(0) {} 156 157 Ty &operator*() const { return *MII; } 158 Ty *operator->() const { return &operator*(); } 159 160 operator Ty*() const { return MII; } 161 162 bool operator==(const bundle_iterator &x) const { 163 return MII == x.MII; 164 } 165 bool operator!=(const bundle_iterator &x) const { 166 return !operator==(x); 167 } 168 169 // Increment and decrement operators... 170 bundle_iterator &operator--() { // predecrement - Back up 171 do { 172 --MII; 173 } while (MII->isInsideBundle()); 174 return *this; 175 } 176 bundle_iterator &operator++() { // preincrement - Advance 177 do { 178 ++MII; 179 } while (MII->isInsideBundle()); 180 return *this; 181 } 182 bundle_iterator operator--(int) { // postdecrement operators... 183 bundle_iterator tmp = *this; 184 do { 185 --MII; 186 } while (MII->isInsideBundle()); 187 return tmp; 188 } 189 bundle_iterator operator++(int) { // postincrement operators... 190 bundle_iterator tmp = *this; 191 do { 192 ++MII; 193 } while (MII->isInsideBundle()); 194 return tmp; 195 } 196 197 IterTy getInstrIterator() const { 198 return MII; 199 } 200 }; 201 202 typedef Instructions::iterator instr_iterator; 203 typedef Instructions::const_iterator const_instr_iterator; 204 typedef std::reverse_iterator<instr_iterator> reverse_instr_iterator; 205 typedef 206 std::reverse_iterator<const_instr_iterator> const_reverse_instr_iterator; 207 208 typedef 209 bundle_iterator<MachineInstr,instr_iterator> iterator; 210 typedef 211 bundle_iterator<const MachineInstr,const_instr_iterator> const_iterator; 212 typedef std::reverse_iterator<const_iterator> const_reverse_iterator; 213 typedef std::reverse_iterator<iterator> reverse_iterator; 214 215 216 unsigned size() const { return (unsigned)Insts.size(); } 217 bool empty() const { return Insts.empty(); } 218 219 MachineInstr& front() { return Insts.front(); } 220 MachineInstr& back() { return Insts.back(); } 221 const MachineInstr& front() const { return Insts.front(); } 222 const MachineInstr& back() const { return Insts.back(); } 223 224 instr_iterator instr_begin() { return Insts.begin(); } 225 const_instr_iterator instr_begin() const { return Insts.begin(); } 226 instr_iterator instr_end() { return Insts.end(); } 227 const_instr_iterator instr_end() const { return Insts.end(); } 228 reverse_instr_iterator instr_rbegin() { return Insts.rbegin(); } 229 const_reverse_instr_iterator instr_rbegin() const { return Insts.rbegin(); } 230 reverse_instr_iterator instr_rend () { return Insts.rend(); } 231 const_reverse_instr_iterator instr_rend () const { return Insts.rend(); } 232 233 iterator begin() { return Insts.begin(); } 234 const_iterator begin() const { return Insts.begin(); } 235 iterator end() { 236 instr_iterator II = instr_end(); 237 if (II != instr_begin()) { 238 while (II->isInsideBundle()) 239 --II; 240 } 241 return II; 242 } 243 const_iterator end() const { 244 const_instr_iterator II = instr_end(); 245 if (II != instr_begin()) { 246 while (II->isInsideBundle()) 247 --II; 248 } 249 return II; 250 } 251 reverse_iterator rbegin() { 252 reverse_instr_iterator II = instr_rbegin(); 253 if (II != instr_rend()) { 254 while (II->isInsideBundle()) 255 ++II; 256 } 257 return II; 258 } 259 const_reverse_iterator rbegin() const { 260 const_reverse_instr_iterator II = instr_rbegin(); 261 if (II != instr_rend()) { 262 while (II->isInsideBundle()) 263 ++II; 264 } 265 return II; 266 } 267 reverse_iterator rend () { return Insts.rend(); } 268 const_reverse_iterator rend () const { return Insts.rend(); } 269 270 271 // Machine-CFG iterators 272 typedef std::vector<MachineBasicBlock *>::iterator pred_iterator; 273 typedef std::vector<MachineBasicBlock *>::const_iterator const_pred_iterator; 274 typedef std::vector<MachineBasicBlock *>::iterator succ_iterator; 275 typedef std::vector<MachineBasicBlock *>::const_iterator const_succ_iterator; 276 typedef std::vector<MachineBasicBlock *>::reverse_iterator 277 pred_reverse_iterator; 278 typedef std::vector<MachineBasicBlock *>::const_reverse_iterator 279 const_pred_reverse_iterator; 280 typedef std::vector<MachineBasicBlock *>::reverse_iterator 281 succ_reverse_iterator; 282 typedef std::vector<MachineBasicBlock *>::const_reverse_iterator 283 const_succ_reverse_iterator; 284 285 pred_iterator pred_begin() { return Predecessors.begin(); } 286 const_pred_iterator pred_begin() const { return Predecessors.begin(); } 287 pred_iterator pred_end() { return Predecessors.end(); } 288 const_pred_iterator pred_end() const { return Predecessors.end(); } 289 pred_reverse_iterator pred_rbegin() 290 { return Predecessors.rbegin();} 291 const_pred_reverse_iterator pred_rbegin() const 292 { return Predecessors.rbegin();} 293 pred_reverse_iterator pred_rend() 294 { return Predecessors.rend(); } 295 const_pred_reverse_iterator pred_rend() const 296 { return Predecessors.rend(); } 297 unsigned pred_size() const { 298 return (unsigned)Predecessors.size(); 299 } 300 bool pred_empty() const { return Predecessors.empty(); } 301 succ_iterator succ_begin() { return Successors.begin(); } 302 const_succ_iterator succ_begin() const { return Successors.begin(); } 303 succ_iterator succ_end() { return Successors.end(); } 304 const_succ_iterator succ_end() const { return Successors.end(); } 305 succ_reverse_iterator succ_rbegin() 306 { return Successors.rbegin(); } 307 const_succ_reverse_iterator succ_rbegin() const 308 { return Successors.rbegin(); } 309 succ_reverse_iterator succ_rend() 310 { return Successors.rend(); } 311 const_succ_reverse_iterator succ_rend() const 312 { return Successors.rend(); } 313 unsigned succ_size() const { 314 return (unsigned)Successors.size(); 315 } 316 bool succ_empty() const { return Successors.empty(); } 317 318 // LiveIn management methods. 319 320 /// addLiveIn - Add the specified register as a live in. Note that it 321 /// is an error to add the same register to the same set more than once. 322 void addLiveIn(unsigned Reg) { LiveIns.push_back(Reg); } 323 324 /// removeLiveIn - Remove the specified register from the live in set. 325 /// 326 void removeLiveIn(unsigned Reg); 327 328 /// isLiveIn - Return true if the specified register is in the live in set. 329 /// 330 bool isLiveIn(unsigned Reg) const; 331 332 // Iteration support for live in sets. These sets are kept in sorted 333 // order by their register number. 334 typedef std::vector<unsigned>::const_iterator livein_iterator; 335 livein_iterator livein_begin() const { return LiveIns.begin(); } 336 livein_iterator livein_end() const { return LiveIns.end(); } 337 bool livein_empty() const { return LiveIns.empty(); } 338 339 /// getAlignment - Return alignment of the basic block. 340 /// The alignment is specified as log2(bytes). 341 /// 342 unsigned getAlignment() const { return Alignment; } 343 344 /// setAlignment - Set alignment of the basic block. 345 /// The alignment is specified as log2(bytes). 346 /// 347 void setAlignment(unsigned Align) { Alignment = Align; } 348 349 /// isLandingPad - Returns true if the block is a landing pad. That is 350 /// this basic block is entered via an exception handler. 351 bool isLandingPad() const { return IsLandingPad; } 352 353 /// setIsLandingPad - Indicates the block is a landing pad. That is 354 /// this basic block is entered via an exception handler. 355 void setIsLandingPad(bool V = true) { IsLandingPad = V; } 356 357 /// getLandingPadSuccessor - If this block has a successor that is a landing 358 /// pad, return it. Otherwise return NULL. 359 const MachineBasicBlock *getLandingPadSuccessor() const; 360 361 // Code Layout methods. 362 363 /// moveBefore/moveAfter - move 'this' block before or after the specified 364 /// block. This only moves the block, it does not modify the CFG or adjust 365 /// potential fall-throughs at the end of the block. 366 void moveBefore(MachineBasicBlock *NewAfter); 367 void moveAfter(MachineBasicBlock *NewBefore); 368 369 /// updateTerminator - Update the terminator instructions in block to account 370 /// for changes to the layout. If the block previously used a fallthrough, 371 /// it may now need a branch, and if it previously used branching it may now 372 /// be able to use a fallthrough. 373 void updateTerminator(); 374 375 // Machine-CFG mutators 376 377 /// addSuccessor - Add succ as a successor of this MachineBasicBlock. 378 /// The Predecessors list of succ is automatically updated. WEIGHT 379 /// parameter is stored in Weights list and it may be used by 380 /// MachineBranchProbabilityInfo analysis to calculate branch probability. 381 /// 382 void addSuccessor(MachineBasicBlock *succ, uint32_t weight = 0); 383 384 /// removeSuccessor - Remove successor from the successors list of this 385 /// MachineBasicBlock. The Predecessors list of succ is automatically updated. 386 /// 387 void removeSuccessor(MachineBasicBlock *succ); 388 389 /// removeSuccessor - Remove specified successor from the successors list of 390 /// this MachineBasicBlock. The Predecessors list of succ is automatically 391 /// updated. Return the iterator to the element after the one removed. 392 /// 393 succ_iterator removeSuccessor(succ_iterator I); 394 395 /// replaceSuccessor - Replace successor OLD with NEW and update weight info. 396 /// 397 void replaceSuccessor(MachineBasicBlock *Old, MachineBasicBlock *New); 398 399 400 /// transferSuccessors - Transfers all the successors from MBB to this 401 /// machine basic block (i.e., copies all the successors fromMBB and 402 /// remove all the successors from fromMBB). 403 void transferSuccessors(MachineBasicBlock *fromMBB); 404 405 /// transferSuccessorsAndUpdatePHIs - Transfers all the successors, as 406 /// in transferSuccessors, and update PHI operands in the successor blocks 407 /// which refer to fromMBB to refer to this. 408 void transferSuccessorsAndUpdatePHIs(MachineBasicBlock *fromMBB); 409 410 /// isSuccessor - Return true if the specified MBB is a successor of this 411 /// block. 412 bool isSuccessor(const MachineBasicBlock *MBB) const; 413 414 /// isLayoutSuccessor - Return true if the specified MBB will be emitted 415 /// immediately after this block, such that if this block exits by 416 /// falling through, control will transfer to the specified MBB. Note 417 /// that MBB need not be a successor at all, for example if this block 418 /// ends with an unconditional branch to some other block. 419 bool isLayoutSuccessor(const MachineBasicBlock *MBB) const; 420 421 /// canFallThrough - Return true if the block can implicitly transfer 422 /// control to the block after it by falling off the end of it. This should 423 /// return false if it can reach the block after it, but it uses an explicit 424 /// branch to do so (e.g., a table jump). True is a conservative answer. 425 bool canFallThrough(); 426 427 /// Returns a pointer to the first instructon in this block that is not a 428 /// PHINode instruction. When adding instruction to the beginning of the 429 /// basic block, they should be added before the returned value, not before 430 /// the first instruction, which might be PHI. 431 /// Returns end() is there's no non-PHI instruction. 432 iterator getFirstNonPHI(); 433 434 /// SkipPHIsAndLabels - Return the first instruction in MBB after I that is 435 /// not a PHI or a label. This is the correct point to insert copies at the 436 /// beginning of a basic block. 437 iterator SkipPHIsAndLabels(iterator I); 438 439 /// getFirstTerminator - returns an iterator to the first terminator 440 /// instruction of this basic block. If a terminator does not exist, 441 /// it returns end() 442 iterator getFirstTerminator(); 443 const_iterator getFirstTerminator() const; 444 445 /// getFirstInstrTerminator - Same getFirstTerminator but it ignores bundles 446 /// and return an instr_iterator instead. 447 instr_iterator getFirstInstrTerminator(); 448 449 /// getLastNonDebugInstr - returns an iterator to the last non-debug 450 /// instruction in the basic block, or end() 451 iterator getLastNonDebugInstr(); 452 const_iterator getLastNonDebugInstr() const; 453 454 /// SplitCriticalEdge - Split the critical edge from this block to the 455 /// given successor block, and return the newly created block, or null 456 /// if splitting is not possible. 457 /// 458 /// This function updates LiveVariables, MachineDominatorTree, and 459 /// MachineLoopInfo, as applicable. 460 MachineBasicBlock *SplitCriticalEdge(MachineBasicBlock *Succ, Pass *P); 461 462 void pop_front() { Insts.pop_front(); } 463 void pop_back() { Insts.pop_back(); } 464 void push_back(MachineInstr *MI) { Insts.push_back(MI); } 465 466 template<typename IT> 467 void insert(instr_iterator I, IT S, IT E) { 468 Insts.insert(I, S, E); 469 } 470 instr_iterator insert(instr_iterator I, MachineInstr *M) { 471 return Insts.insert(I, M); 472 } 473 instr_iterator insertAfter(instr_iterator I, MachineInstr *M) { 474 return Insts.insertAfter(I, M); 475 } 476 477 template<typename IT> 478 void insert(iterator I, IT S, IT E) { 479 Insts.insert(I.getInstrIterator(), S, E); 480 } 481 iterator insert(iterator I, MachineInstr *M) { 482 return Insts.insert(I.getInstrIterator(), M); 483 } 484 iterator insertAfter(iterator I, MachineInstr *M) { 485 return Insts.insertAfter(I.getInstrIterator(), M); 486 } 487 488 /// erase - Remove the specified element or range from the instruction list. 489 /// These functions delete any instructions removed. 490 /// 491 instr_iterator erase(instr_iterator I) { 492 return Insts.erase(I); 493 } 494 instr_iterator erase(instr_iterator I, instr_iterator E) { 495 return Insts.erase(I, E); 496 } 497 instr_iterator erase_instr(MachineInstr *I) { 498 instr_iterator MII(I); 499 return erase(MII); 500 } 501 502 iterator erase(iterator I); 503 iterator erase(iterator I, iterator E) { 504 return Insts.erase(I.getInstrIterator(), E.getInstrIterator()); 505 } 506 iterator erase(MachineInstr *I) { 507 iterator MII(I); 508 return erase(MII); 509 } 510 511 /// remove - Remove the instruction from the instruction list. This function 512 /// does not delete the instruction. WARNING: Note, if the specified 513 /// instruction is a bundle this function will remove all the bundled 514 /// instructions as well. It is up to the caller to keep a list of the 515 /// bundled instructions and re-insert them if desired. This function is 516 /// *not recommended* for manipulating instructions with bundles. Use 517 /// splice instead. 518 MachineInstr *remove(MachineInstr *I); 519 void clear() { 520 Insts.clear(); 521 } 522 523 /// splice - Take an instruction from MBB 'Other' at the position From, 524 /// and insert it into this MBB right before 'where'. 525 void splice(instr_iterator where, MachineBasicBlock *Other, 526 instr_iterator From) { 527 Insts.splice(where, Other->Insts, From); 528 } 529 void splice(iterator where, MachineBasicBlock *Other, iterator From); 530 531 /// splice - Take a block of instructions from MBB 'Other' in the range [From, 532 /// To), and insert them into this MBB right before 'where'. 533 void splice(instr_iterator where, MachineBasicBlock *Other, instr_iterator From, 534 instr_iterator To) { 535 Insts.splice(where, Other->Insts, From, To); 536 } 537 void splice(iterator where, MachineBasicBlock *Other, iterator From, 538 iterator To) { 539 Insts.splice(where.getInstrIterator(), Other->Insts, 540 From.getInstrIterator(), To.getInstrIterator()); 541 } 542 543 /// removeFromParent - This method unlinks 'this' from the containing 544 /// function, and returns it, but does not delete it. 545 MachineBasicBlock *removeFromParent(); 546 547 /// eraseFromParent - This method unlinks 'this' from the containing 548 /// function and deletes it. 549 void eraseFromParent(); 550 551 /// ReplaceUsesOfBlockWith - Given a machine basic block that branched to 552 /// 'Old', change the code and CFG so that it branches to 'New' instead. 553 void ReplaceUsesOfBlockWith(MachineBasicBlock *Old, MachineBasicBlock *New); 554 555 /// CorrectExtraCFGEdges - Various pieces of code can cause excess edges in 556 /// the CFG to be inserted. If we have proven that MBB can only branch to 557 /// DestA and DestB, remove any other MBB successors from the CFG. DestA and 558 /// DestB can be null. Besides DestA and DestB, retain other edges leading 559 /// to LandingPads (currently there can be only one; we don't check or require 560 /// that here). Note it is possible that DestA and/or DestB are LandingPads. 561 bool CorrectExtraCFGEdges(MachineBasicBlock *DestA, 562 MachineBasicBlock *DestB, 563 bool isCond); 564 565 /// findDebugLoc - find the next valid DebugLoc starting at MBBI, skipping 566 /// any DBG_VALUE instructions. Return UnknownLoc if there is none. 567 DebugLoc findDebugLoc(instr_iterator MBBI); 568 DebugLoc findDebugLoc(iterator MBBI) { 569 return findDebugLoc(MBBI.getInstrIterator()); 570 } 571 572 // Debugging methods. 573 void dump() const; 574 void print(raw_ostream &OS, SlotIndexes* = 0) const; 575 576 /// getNumber - MachineBasicBlocks are uniquely numbered at the function 577 /// level, unless they're not in a MachineFunction yet, in which case this 578 /// will return -1. 579 /// 580 int getNumber() const { return Number; } 581 void setNumber(int N) { Number = N; } 582 583 /// getSymbol - Return the MCSymbol for this basic block. 584 /// 585 MCSymbol *getSymbol() const; 586 587 588private: 589 /// getWeightIterator - Return weight iterator corresponding to the I 590 /// successor iterator. 591 weight_iterator getWeightIterator(succ_iterator I); 592 593 friend class MachineBranchProbabilityInfo; 594 595 /// getSuccWeight - Return weight of the edge from this block to MBB. This 596 /// method should NOT be called directly, but by using getEdgeWeight method 597 /// from MachineBranchProbabilityInfo class. 598 uint32_t getSuccWeight(MachineBasicBlock *succ); 599 600 601 // Methods used to maintain doubly linked list of blocks... 602 friend struct ilist_traits<MachineBasicBlock>; 603 604 // Machine-CFG mutators 605 606 /// addPredecessor - Remove pred as a predecessor of this MachineBasicBlock. 607 /// Don't do this unless you know what you're doing, because it doesn't 608 /// update pred's successors list. Use pred->addSuccessor instead. 609 /// 610 void addPredecessor(MachineBasicBlock *pred); 611 612 /// removePredecessor - Remove pred as a predecessor of this 613 /// MachineBasicBlock. Don't do this unless you know what you're 614 /// doing, because it doesn't update pred's successors list. Use 615 /// pred->removeSuccessor instead. 616 /// 617 void removePredecessor(MachineBasicBlock *pred); 618}; 619 620raw_ostream& operator<<(raw_ostream &OS, const MachineBasicBlock &MBB); 621 622void WriteAsOperand(raw_ostream &, const MachineBasicBlock*, bool t); 623 624// This is useful when building IndexedMaps keyed on basic block pointers. 625struct MBB2NumberFunctor : 626 public std::unary_function<const MachineBasicBlock*, unsigned> { 627 unsigned operator()(const MachineBasicBlock *MBB) const { 628 return MBB->getNumber(); 629 } 630}; 631 632//===--------------------------------------------------------------------===// 633// GraphTraits specializations for machine basic block graphs (machine-CFGs) 634//===--------------------------------------------------------------------===// 635 636// Provide specializations of GraphTraits to be able to treat a 637// MachineFunction as a graph of MachineBasicBlocks... 638// 639 640template <> struct GraphTraits<MachineBasicBlock *> { 641 typedef MachineBasicBlock NodeType; 642 typedef MachineBasicBlock::succ_iterator ChildIteratorType; 643 644 static NodeType *getEntryNode(MachineBasicBlock *BB) { return BB; } 645 static inline ChildIteratorType child_begin(NodeType *N) { 646 return N->succ_begin(); 647 } 648 static inline ChildIteratorType child_end(NodeType *N) { 649 return N->succ_end(); 650 } 651}; 652 653template <> struct GraphTraits<const MachineBasicBlock *> { 654 typedef const MachineBasicBlock NodeType; 655 typedef MachineBasicBlock::const_succ_iterator ChildIteratorType; 656 657 static NodeType *getEntryNode(const MachineBasicBlock *BB) { return BB; } 658 static inline ChildIteratorType child_begin(NodeType *N) { 659 return N->succ_begin(); 660 } 661 static inline ChildIteratorType child_end(NodeType *N) { 662 return N->succ_end(); 663 } 664}; 665 666// Provide specializations of GraphTraits to be able to treat a 667// MachineFunction as a graph of MachineBasicBlocks... and to walk it 668// in inverse order. Inverse order for a function is considered 669// to be when traversing the predecessor edges of a MBB 670// instead of the successor edges. 671// 672template <> struct GraphTraits<Inverse<MachineBasicBlock*> > { 673 typedef MachineBasicBlock NodeType; 674 typedef MachineBasicBlock::pred_iterator ChildIteratorType; 675 static NodeType *getEntryNode(Inverse<MachineBasicBlock *> G) { 676 return G.Graph; 677 } 678 static inline ChildIteratorType child_begin(NodeType *N) { 679 return N->pred_begin(); 680 } 681 static inline ChildIteratorType child_end(NodeType *N) { 682 return N->pred_end(); 683 } 684}; 685 686template <> struct GraphTraits<Inverse<const MachineBasicBlock*> > { 687 typedef const MachineBasicBlock NodeType; 688 typedef MachineBasicBlock::const_pred_iterator ChildIteratorType; 689 static NodeType *getEntryNode(Inverse<const MachineBasicBlock*> G) { 690 return G.Graph; 691 } 692 static inline ChildIteratorType child_begin(NodeType *N) { 693 return N->pred_begin(); 694 } 695 static inline ChildIteratorType child_end(NodeType *N) { 696 return N->pred_end(); 697 } 698}; 699 700} // End llvm namespace 701 702#endif 703