MachineBasicBlock.h revision a971dbdde27fd4ff53dbebdd4aaf87826d081aa2
1cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles)//===-- llvm/CodeGen/MachineBasicBlock.h ------------------------*- C++ -*-===// 2cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles)// 3cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles)// The LLVM Compiler Infrastructure 4cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles)// 5cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles)// This file is distributed under the University of Illinois Open Source 6cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles)// License. See LICENSE.TXT for details. 7cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles)// 8cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles)//===----------------------------------------------------------------------===// 9cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles)// 10cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles)// Collect the sequence of machine instructions for a basic block. 11cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles)// 12cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles)//===----------------------------------------------------------------------===// 13cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles) 14cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles)#ifndef LLVM_CODEGEN_MACHINEBASICBLOCK_H 15cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles)#define LLVM_CODEGEN_MACHINEBASICBLOCK_H 16cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles) 17cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles)#include "llvm/CodeGen/MachineInstr.h" 18cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles)#include "llvm/ADT/GraphTraits.h" 19cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles)#include "llvm/ADT/ilist" 20cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles)#include "llvm/Support/Streams.h" 21cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles) 22cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles)namespace llvm { 23cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles) class MachineFunction; 24116680a4aac90f2aa7413d9095a592090648e557Ben Murdoch 25cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles)// ilist_traits 26cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles)template <> 27cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles)struct ilist_traits<MachineInstr> { 28cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles)protected: 29cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles) // this is only set by the MachineBasicBlock owning the ilist 30cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles) friend class MachineBasicBlock; 31cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles) MachineBasicBlock* parent; 32cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles) 33cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles)public: 34cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles) ilist_traits<MachineInstr>() : parent(0) { } 3546d4c2bc3267f3f028f39e7e311b0f89aba2e4fdTorne (Richard Coles) 3646d4c2bc3267f3f028f39e7e311b0f89aba2e4fdTorne (Richard Coles) static MachineInstr* getPrev(MachineInstr* N) { return N->Prev; } 3746d4c2bc3267f3f028f39e7e311b0f89aba2e4fdTorne (Richard Coles) static MachineInstr* getNext(MachineInstr* N) { return N->Next; } 3846d4c2bc3267f3f028f39e7e311b0f89aba2e4fdTorne (Richard Coles) 39cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles) static const MachineInstr* 40cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles) getPrev(const MachineInstr* N) { return N->Prev; } 4146d4c2bc3267f3f028f39e7e311b0f89aba2e4fdTorne (Richard Coles) 42cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles) static const MachineInstr* 43cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles) getNext(const MachineInstr* N) { return N->Next; } 44cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles) 4546d4c2bc3267f3f028f39e7e311b0f89aba2e4fdTorne (Richard Coles) static void setPrev(MachineInstr* N, MachineInstr* prev) { N->Prev = prev; } 4646d4c2bc3267f3f028f39e7e311b0f89aba2e4fdTorne (Richard Coles) static void setNext(MachineInstr* N, MachineInstr* next) { N->Next = next; } 4746d4c2bc3267f3f028f39e7e311b0f89aba2e4fdTorne (Richard Coles) 48cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles) static MachineInstr* createSentinel(); 49cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles) static void destroySentinel(MachineInstr *MI) { delete MI; } 50cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles) void addNodeToList(MachineInstr* N); 51cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles) void removeNodeFromList(MachineInstr* N); 52cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles) void transferNodesFromList( 53 iplist<MachineInstr, ilist_traits<MachineInstr> >& toList, 54 ilist_iterator<MachineInstr> first, 55 ilist_iterator<MachineInstr> last); 56}; 57 58class BasicBlock; 59 60class MachineBasicBlock { 61 typedef ilist<MachineInstr> Instructions; 62 Instructions Insts; 63 MachineBasicBlock *Prev, *Next; 64 const BasicBlock *BB; 65 int Number; 66 MachineFunction *xParent; 67 68 void setParent(MachineFunction *P) { xParent = P; } 69 70 /// Predecessors/Successors - Keep track of the predecessor / successor 71 /// basicblocks. 72 std::vector<MachineBasicBlock *> Predecessors; 73 std::vector<MachineBasicBlock *> Successors; 74 75 /// LiveIns - Keep track of the physical registers that are livein of 76 /// the basicblock. 77 std::vector<unsigned> LiveIns; 78 79 /// Alignment - Alignment of the basic block. Zero if the basic block does 80 /// not need to be aligned. 81 unsigned Alignment; 82 83 /// IsLandingPad - Indicate that this basic block is entered via an 84 /// exception handler. 85 bool IsLandingPad; 86 87public: 88 explicit MachineBasicBlock(const BasicBlock *bb = 0) 89 : Prev(0), Next(0), BB(bb), Number(-1), xParent(0), 90 Alignment(0), IsLandingPad(false) { 91 Insts.parent = this; 92 } 93 94 ~MachineBasicBlock(); 95 96 /// getBasicBlock - Return the LLVM basic block that this instance 97 /// corresponded to originally. 98 /// 99 const BasicBlock *getBasicBlock() const { return BB; } 100 101 /// getParent - Return the MachineFunction containing this basic block. 102 /// 103 const MachineFunction *getParent() const { return xParent; } 104 MachineFunction *getParent() { return xParent; } 105 106 typedef ilist<MachineInstr>::iterator iterator; 107 typedef ilist<MachineInstr>::const_iterator const_iterator; 108 typedef std::reverse_iterator<const_iterator> const_reverse_iterator; 109 typedef std::reverse_iterator<iterator> reverse_iterator; 110 111 unsigned size() const { return Insts.size(); } 112 bool empty() const { return Insts.empty(); } 113 114 MachineInstr& front() { return Insts.front(); } 115 MachineInstr& back() { return Insts.back(); } 116 117 iterator begin() { return Insts.begin(); } 118 const_iterator begin() const { return Insts.begin(); } 119 iterator end() { return Insts.end(); } 120 const_iterator end() const { return Insts.end(); } 121 reverse_iterator rbegin() { return Insts.rbegin(); } 122 const_reverse_iterator rbegin() const { return Insts.rbegin(); } 123 reverse_iterator rend () { return Insts.rend(); } 124 const_reverse_iterator rend () const { return Insts.rend(); } 125 126 // Machine-CFG iterators 127 typedef std::vector<MachineBasicBlock *>::iterator pred_iterator; 128 typedef std::vector<MachineBasicBlock *>::const_iterator const_pred_iterator; 129 typedef std::vector<MachineBasicBlock *>::iterator succ_iterator; 130 typedef std::vector<MachineBasicBlock *>::const_iterator const_succ_iterator; 131 typedef std::vector<MachineBasicBlock *>::reverse_iterator 132 pred_reverse_iterator; 133 typedef std::vector<MachineBasicBlock *>::const_reverse_iterator 134 const_pred_reverse_iterator; 135 typedef std::vector<MachineBasicBlock *>::reverse_iterator 136 succ_reverse_iterator; 137 typedef std::vector<MachineBasicBlock *>::const_reverse_iterator 138 const_succ_reverse_iterator; 139 140 pred_iterator pred_begin() { return Predecessors.begin(); } 141 const_pred_iterator pred_begin() const { return Predecessors.begin(); } 142 pred_iterator pred_end() { return Predecessors.end(); } 143 const_pred_iterator pred_end() const { return Predecessors.end(); } 144 pred_reverse_iterator pred_rbegin() 145 { return Predecessors.rbegin();} 146 const_pred_reverse_iterator pred_rbegin() const 147 { return Predecessors.rbegin();} 148 pred_reverse_iterator pred_rend() 149 { return Predecessors.rend(); } 150 const_pred_reverse_iterator pred_rend() const 151 { return Predecessors.rend(); } 152 unsigned pred_size() const { return Predecessors.size(); } 153 bool pred_empty() const { return Predecessors.empty(); } 154 succ_iterator succ_begin() { return Successors.begin(); } 155 const_succ_iterator succ_begin() const { return Successors.begin(); } 156 succ_iterator succ_end() { return Successors.end(); } 157 const_succ_iterator succ_end() const { return Successors.end(); } 158 succ_reverse_iterator succ_rbegin() 159 { return Successors.rbegin(); } 160 const_succ_reverse_iterator succ_rbegin() const 161 { return Successors.rbegin(); } 162 succ_reverse_iterator succ_rend() 163 { return Successors.rend(); } 164 const_succ_reverse_iterator succ_rend() const 165 { return Successors.rend(); } 166 unsigned succ_size() const { return Successors.size(); } 167 bool succ_empty() const { return Successors.empty(); } 168 169 // LiveIn management methods. 170 171 /// addLiveIn - Add the specified register as a live in. Note that it 172 /// is an error to add the same register to the same set more than once. 173 void addLiveIn(unsigned Reg) { LiveIns.push_back(Reg); } 174 175 /// removeLiveIn - Remove the specified register from the live in set. 176 /// 177 void removeLiveIn(unsigned Reg); 178 179 /// isLiveIn - Return true if the specified register is in the live in set. 180 /// 181 bool isLiveIn(unsigned Reg) const; 182 183 // Iteration support for live in sets. These sets are kept in sorted 184 // order by their register number. 185 typedef std::vector<unsigned>::iterator livein_iterator; 186 typedef std::vector<unsigned>::const_iterator const_livein_iterator; 187 livein_iterator livein_begin() { return LiveIns.begin(); } 188 const_livein_iterator livein_begin() const { return LiveIns.begin(); } 189 livein_iterator livein_end() { return LiveIns.end(); } 190 const_livein_iterator livein_end() const { return LiveIns.end(); } 191 bool livein_empty() const { return LiveIns.empty(); } 192 193 /// getAlignment - Return alignment of the basic block. 194 /// 195 unsigned getAlignment() const { return Alignment; } 196 197 /// setAlignment - Set alignment of the basic block. 198 /// 199 void setAlignment(unsigned Align) { Alignment = Align; } 200 201 /// isLandingPad - Returns true if the block is a landing pad. That is 202 /// this basic block is entered via an exception handler. 203 bool isLandingPad() const { return IsLandingPad; } 204 205 /// setIsLandingPad - Indicates the block is a landing pad. That is 206 /// this basic block is entered via an exception handler. 207 void setIsLandingPad() { IsLandingPad = true; } 208 209 // Code Layout methods. 210 211 /// moveBefore/moveAfter - move 'this' block before or after the specified 212 /// block. This only moves the block, it does not modify the CFG or adjust 213 /// potential fall-throughs at the end of the block. 214 void moveBefore(MachineBasicBlock *NewAfter); 215 void moveAfter(MachineBasicBlock *NewBefore); 216 217 // Machine-CFG mutators 218 219 /// addSuccessor - Add succ as a successor of this MachineBasicBlock. 220 /// The Predecessors list of succ is automatically updated. 221 /// 222 void addSuccessor(MachineBasicBlock *succ); 223 224 /// removeSuccessor - Remove successor from the successors list of this 225 /// MachineBasicBlock. The Predecessors list of succ is automatically updated. 226 /// 227 void removeSuccessor(MachineBasicBlock *succ); 228 229 /// removeSuccessor - Remove specified successor from the successors list of 230 /// this MachineBasicBlock. The Predecessors list of succ is automatically 231 /// updated. Return the iterator to the element after the one removed. 232 /// 233 succ_iterator removeSuccessor(succ_iterator I); 234 235 /// isSuccessor - Return true if the specified MBB is a successor of this 236 /// block. 237 bool isSuccessor(MachineBasicBlock *MBB) const; 238 239 /// getFirstTerminator - returns an iterator to the first terminator 240 /// instruction of this basic block. If a terminator does not exist, 241 /// it returns end() 242 iterator getFirstTerminator(); 243 244 void pop_front() { Insts.pop_front(); } 245 void pop_back() { Insts.pop_back(); } 246 void push_back(MachineInstr *MI) { Insts.push_back(MI); } 247 template<typename IT> 248 void insert(iterator I, IT S, IT E) { Insts.insert(I, S, E); } 249 iterator insert(iterator I, MachineInstr *M) { return Insts.insert(I, M); } 250 251 // erase - Remove the specified element or range from the instruction list. 252 // These functions delete any instructions removed. 253 // 254 iterator erase(iterator I) { return Insts.erase(I); } 255 iterator erase(iterator I, iterator E) { return Insts.erase(I, E); } 256 MachineInstr *remove(MachineInstr *I) { return Insts.remove(I); } 257 void clear() { Insts.clear(); } 258 259 /// splice - Take a block of instructions from MBB 'Other' in the range [From, 260 /// To), and insert them into this MBB right before 'where'. 261 void splice(iterator where, MachineBasicBlock *Other, iterator From, 262 iterator To) { 263 Insts.splice(where, Other->Insts, From, To); 264 } 265 266 /// ReplaceUsesOfBlockWith - Given a machine basic block that branched to 267 /// 'Old', change the code and CFG so that it branches to 'New' instead. 268 void ReplaceUsesOfBlockWith(MachineBasicBlock *Old, MachineBasicBlock *New); 269 270 /// CorrectExtraCFGEdges - Various pieces of code can cause excess edges in 271 /// the CFG to be inserted. If we have proven that MBB can only branch to 272 /// DestA and DestB, remove any other MBB successors from the CFG. DestA and 273 /// DestB can be null. Besides DestA and DestB, retain other edges leading 274 /// to LandingPads (currently there can be only one; we don't check or require 275 /// that here). Note it is possible that DestA and/or DestB are LandingPads. 276 bool CorrectExtraCFGEdges(MachineBasicBlock *DestA, 277 MachineBasicBlock *DestB, 278 bool isCond); 279 280 // Debugging methods. 281 void dump() const; 282 void print(std::ostream &OS) const; 283 void print(std::ostream *OS) const { if (OS) print(*OS); } 284 285 /// getNumber - MachineBasicBlocks are uniquely numbered at the function 286 /// level, unless they're not in a MachineFunction yet, in which case this 287 /// will return -1. 288 /// 289 int getNumber() const { return Number; } 290 void setNumber(int N) { Number = N; } 291 292private: // Methods used to maintain doubly linked list of blocks... 293 friend struct ilist_traits<MachineBasicBlock>; 294 295 MachineBasicBlock *getPrev() const { return Prev; } 296 MachineBasicBlock *getNext() const { return Next; } 297 void setPrev(MachineBasicBlock *P) { Prev = P; } 298 void setNext(MachineBasicBlock *N) { Next = N; } 299 300 // Machine-CFG mutators 301 302 /// addPredecessor - Remove pred as a predecessor of this MachineBasicBlock. 303 /// Don't do this unless you know what you're doing, because it doesn't 304 /// update pred's successors list. Use pred->addSuccessor instead. 305 /// 306 void addPredecessor(MachineBasicBlock *pred); 307 308 /// removePredecessor - Remove pred as a predecessor of this 309 /// MachineBasicBlock. Don't do this unless you know what you're 310 /// doing, because it doesn't update pred's successors list. Use 311 /// pred->removeSuccessor instead. 312 /// 313 void removePredecessor(MachineBasicBlock *pred); 314}; 315 316std::ostream& operator<<(std::ostream &OS, const MachineBasicBlock &MBB); 317 318//===--------------------------------------------------------------------===// 319// GraphTraits specializations for machine basic block graphs (machine-CFGs) 320//===--------------------------------------------------------------------===// 321 322// Provide specializations of GraphTraits to be able to treat a 323// MachineFunction as a graph of MachineBasicBlocks... 324// 325 326template <> struct GraphTraits<MachineBasicBlock *> { 327 typedef MachineBasicBlock NodeType; 328 typedef MachineBasicBlock::succ_iterator ChildIteratorType; 329 330 static NodeType *getEntryNode(MachineBasicBlock *BB) { return BB; } 331 static inline ChildIteratorType child_begin(NodeType *N) { 332 return N->succ_begin(); 333 } 334 static inline ChildIteratorType child_end(NodeType *N) { 335 return N->succ_end(); 336 } 337}; 338 339template <> struct GraphTraits<const MachineBasicBlock *> { 340 typedef const MachineBasicBlock NodeType; 341 typedef MachineBasicBlock::const_succ_iterator ChildIteratorType; 342 343 static NodeType *getEntryNode(const MachineBasicBlock *BB) { return BB; } 344 static inline ChildIteratorType child_begin(NodeType *N) { 345 return N->succ_begin(); 346 } 347 static inline ChildIteratorType child_end(NodeType *N) { 348 return N->succ_end(); 349 } 350}; 351 352// Provide specializations of GraphTraits to be able to treat a 353// MachineFunction as a graph of MachineBasicBlocks... and to walk it 354// in inverse order. Inverse order for a function is considered 355// to be when traversing the predecessor edges of a MBB 356// instead of the successor edges. 357// 358template <> struct GraphTraits<Inverse<MachineBasicBlock*> > { 359 typedef MachineBasicBlock NodeType; 360 typedef MachineBasicBlock::pred_iterator ChildIteratorType; 361 static NodeType *getEntryNode(Inverse<MachineBasicBlock *> G) { 362 return G.Graph; 363 } 364 static inline ChildIteratorType child_begin(NodeType *N) { 365 return N->pred_begin(); 366 } 367 static inline ChildIteratorType child_end(NodeType *N) { 368 return N->pred_end(); 369 } 370}; 371 372template <> struct GraphTraits<Inverse<const MachineBasicBlock*> > { 373 typedef const MachineBasicBlock NodeType; 374 typedef MachineBasicBlock::const_pred_iterator ChildIteratorType; 375 static NodeType *getEntryNode(Inverse<const MachineBasicBlock*> G) { 376 return G.Graph; 377 } 378 static inline ChildIteratorType child_begin(NodeType *N) { 379 return N->pred_begin(); 380 } 381 static inline ChildIteratorType child_end(NodeType *N) { 382 return N->pred_end(); 383 } 384}; 385 386} // End llvm namespace 387 388#endif 389