MachineBasicBlock.h revision 0370fad74b48388412c52d1325512f2c218487fa
1//===-- llvm/CodeGen/MachineBasicBlock.h ------------------------*- C++ -*-===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file was developed by the LLVM research group and is distributed under 6// the University of Illinois Open Source 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/ADT/ilist" 20#include "llvm/Support/Streams.h" 21 22namespace llvm { 23 class MachineFunction; 24 25// ilist_traits 26template <> 27struct ilist_traits<MachineInstr> { 28protected: 29 // this is only set by the MachineBasicBlock owning the ilist 30 friend class MachineBasicBlock; 31 MachineBasicBlock* parent; 32 33public: 34 ilist_traits<MachineInstr>() : parent(0) { } 35 36 static MachineInstr* getPrev(MachineInstr* N) { return N->prev; } 37 static MachineInstr* getNext(MachineInstr* N) { return N->next; } 38 39 static const MachineInstr* 40 getPrev(const MachineInstr* N) { return N->prev; } 41 42 static const MachineInstr* 43 getNext(const MachineInstr* N) { return N->next; } 44 45 static void setPrev(MachineInstr* N, MachineInstr* prev) { N->prev = prev; } 46 static void setNext(MachineInstr* N, MachineInstr* next) { N->next = next; } 47 48 static MachineInstr* createSentinel(); 49 static void destroySentinel(MachineInstr *MI) { delete MI; } 50 void addNodeToList(MachineInstr* N); 51 void removeNodeFromList(MachineInstr* N); 52 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 *Parent; 67 68 /// Predecessors/Successors - Keep track of the predecessor / successor 69 /// basicblocks. 70 std::vector<MachineBasicBlock *> Predecessors; 71 std::vector<MachineBasicBlock *> Successors; 72 73 /// LiveIns - Keep track of the physical registers that are livein of 74 /// the basicblock. 75 std::vector<unsigned> LiveIns; 76 77 /// IsLandingPad - Indicate that this basic block is entered via an 78 /// exception handler. 79 bool IsLandingPad; 80 81public: 82 explicit MachineBasicBlock(const BasicBlock *bb = 0) : Prev(0), Next(0), 83 BB(bb), Number(-1), 84 Parent(0), 85 IsLandingPad(false) { 86 Insts.parent = this; 87 } 88 89 ~MachineBasicBlock(); 90 91 /// getBasicBlock - Return the LLVM basic block that this instance 92 /// corresponded to originally. 93 /// 94 const BasicBlock *getBasicBlock() const { return BB; } 95 96 /// getParent - Return the MachineFunction containing this basic block. 97 /// 98 const MachineFunction *getParent() const { return Parent; } 99 MachineFunction *getParent() { return Parent; } 100 101 typedef ilist<MachineInstr>::iterator iterator; 102 typedef ilist<MachineInstr>::const_iterator const_iterator; 103 typedef std::reverse_iterator<const_iterator> const_reverse_iterator; 104 typedef std::reverse_iterator<iterator> reverse_iterator; 105 106 unsigned size() const { return Insts.size(); } 107 bool empty() const { return Insts.empty(); } 108 109 MachineInstr& front() { return Insts.front(); } 110 MachineInstr& back() { return Insts.back(); } 111 112 iterator begin() { return Insts.begin(); } 113 const_iterator begin() const { return Insts.begin(); } 114 iterator end() { return Insts.end(); } 115 const_iterator end() const { return Insts.end(); } 116 reverse_iterator rbegin() { return Insts.rbegin(); } 117 const_reverse_iterator rbegin() const { return Insts.rbegin(); } 118 reverse_iterator rend () { return Insts.rend(); } 119 const_reverse_iterator rend () const { return Insts.rend(); } 120 121 // Machine-CFG iterators 122 typedef std::vector<MachineBasicBlock *>::iterator pred_iterator; 123 typedef std::vector<MachineBasicBlock *>::const_iterator const_pred_iterator; 124 typedef std::vector<MachineBasicBlock *>::iterator succ_iterator; 125 typedef std::vector<MachineBasicBlock *>::const_iterator const_succ_iterator; 126 typedef std::vector<MachineBasicBlock *>::reverse_iterator 127 pred_reverse_iterator; 128 typedef std::vector<MachineBasicBlock *>::const_reverse_iterator 129 const_pred_reverse_iterator; 130 typedef std::vector<MachineBasicBlock *>::reverse_iterator 131 succ_reverse_iterator; 132 typedef std::vector<MachineBasicBlock *>::const_reverse_iterator 133 const_succ_reverse_iterator; 134 135 pred_iterator pred_begin() { return Predecessors.begin(); } 136 const_pred_iterator pred_begin() const { return Predecessors.begin(); } 137 pred_iterator pred_end() { return Predecessors.end(); } 138 const_pred_iterator pred_end() const { return Predecessors.end(); } 139 pred_reverse_iterator pred_rbegin() 140 { return Predecessors.rbegin();} 141 const_pred_reverse_iterator pred_rbegin() const 142 { return Predecessors.rbegin();} 143 pred_reverse_iterator pred_rend() 144 { return Predecessors.rend(); } 145 const_pred_reverse_iterator pred_rend() const 146 { return Predecessors.rend(); } 147 unsigned pred_size() const { return Predecessors.size(); } 148 bool pred_empty() const { return Predecessors.empty(); } 149 succ_iterator succ_begin() { return Successors.begin(); } 150 const_succ_iterator succ_begin() const { return Successors.begin(); } 151 succ_iterator succ_end() { return Successors.end(); } 152 const_succ_iterator succ_end() const { return Successors.end(); } 153 succ_reverse_iterator succ_rbegin() 154 { return Successors.rbegin(); } 155 const_succ_reverse_iterator succ_rbegin() const 156 { return Successors.rbegin(); } 157 succ_reverse_iterator succ_rend() 158 { return Successors.rend(); } 159 const_succ_reverse_iterator succ_rend() const 160 { return Successors.rend(); } 161 unsigned succ_size() const { return Successors.size(); } 162 bool succ_empty() const { return Successors.empty(); } 163 164 // LiveIn management methods. 165 166 /// addLiveIn - Add the specified register as a live in. Note that it 167 /// is an error to add the same register to the same set more than once. 168 void addLiveIn(unsigned Reg) { LiveIns.push_back(Reg); } 169 170 /// removeLiveIn - Remove the specified register from the live in set. 171 /// 172 void removeLiveIn(unsigned Reg); 173 174 // Iteration support for live in sets. These sets are kept in sorted 175 // order by their register number. 176 typedef std::vector<unsigned>::iterator livein_iterator; 177 typedef std::vector<unsigned>::const_iterator const_livein_iterator; 178 livein_iterator livein_begin() { return LiveIns.begin(); } 179 const_livein_iterator livein_begin() const { return LiveIns.begin(); } 180 livein_iterator livein_end() { return LiveIns.end(); } 181 const_livein_iterator livein_end() const { return LiveIns.end(); } 182 bool livein_empty() const { return LiveIns.empty(); } 183 184 /// isLandingPad - Returns true if the block is a landing pad. That is 185 /// this basic block is entered via an exception handler. 186 bool isLandingPad() const { return IsLandingPad; } 187 188 /// setIsLandingPad - Indicates the block is a landing pad. That is 189 /// this basic block is entered via an exception handler. 190 void setIsLandingPad() { IsLandingPad = true; } 191 192 // Code Layout methods. 193 194 /// moveBefore/moveAfter - move 'this' block before or after the specified 195 /// block. This only moves the block, it does not modify the CFG or adjust 196 /// potential fall-throughs at the end of the block. 197 void moveBefore(MachineBasicBlock *NewAfter); 198 void moveAfter(MachineBasicBlock *NewBefore); 199 200 // Machine-CFG mutators 201 202 /// addSuccessor - Add succ as a successor of this MachineBasicBlock. 203 /// The Predecessors list of succ is automatically updated. 204 /// 205 void addSuccessor(MachineBasicBlock *succ); 206 207 /// removeSuccessor - Remove successor from the successors list of this 208 /// MachineBasicBlock. The Predecessors list of succ is automatically updated. 209 /// 210 void removeSuccessor(MachineBasicBlock *succ); 211 212 /// removeSuccessor - Remove specified successor from the successors list of 213 /// this MachineBasicBlock. The Predecessors list of succ is automatically 214 /// updated. 215 /// 216 void removeSuccessor(succ_iterator I); 217 218 /// isSuccessor - Return true if the specified MBB is a successor of this 219 /// block. 220 bool isSuccessor(MachineBasicBlock *MBB) const; 221 222 /// getFirstTerminator - returns an iterator to the first terminator 223 /// instruction of this basic block. If a terminator does not exist, 224 /// it returns end() 225 iterator getFirstTerminator(); 226 227 void pop_front() { Insts.pop_front(); } 228 void pop_back() { Insts.pop_back(); } 229 void push_back(MachineInstr *MI) { Insts.push_back(MI); } 230 template<typename IT> 231 void insert(iterator I, IT S, IT E) { Insts.insert(I, S, E); } 232 iterator insert(iterator I, MachineInstr *M) { return Insts.insert(I, M); } 233 234 // erase - Remove the specified element or range from the instruction list. 235 // These functions delete any instructions removed. 236 // 237 iterator erase(iterator I) { return Insts.erase(I); } 238 iterator erase(iterator I, iterator E) { return Insts.erase(I, E); } 239 MachineInstr *remove(MachineInstr *I) { return Insts.remove(I); } 240 void clear() { Insts.clear(); } 241 242 /// splice - Take a block of instructions from MBB 'Other' in the range [From, 243 /// To), and insert them into this MBB right before 'where'. 244 void splice(iterator where, MachineBasicBlock *Other, iterator From, 245 iterator To) { 246 Insts.splice(where, Other->Insts, From, To); 247 } 248 249 /// ReplaceUsesOfBlockWith - Given a machine basic block that branched to 250 /// 'Old', change the code and CFG so that it branches to 'New' instead. 251 void ReplaceUsesOfBlockWith(MachineBasicBlock *Old, MachineBasicBlock *New); 252 253 // Debugging methods. 254 void dump() const; 255 void print(std::ostream &OS) const; 256 void print(std::ostream *OS) const { if (OS) print(*OS); } 257 258 /// getNumber - MachineBasicBlocks are uniquely numbered at the function 259 /// level, unless they're not in a MachineFunction yet, in which case this 260 /// will return -1. 261 /// 262 int getNumber() const { return Number; } 263 void setNumber(int N) { Number = N; } 264 265private: // Methods used to maintain doubly linked list of blocks... 266 friend struct ilist_traits<MachineBasicBlock>; 267 268 MachineBasicBlock *getPrev() const { return Prev; } 269 MachineBasicBlock *getNext() const { return Next; } 270 void setPrev(MachineBasicBlock *P) { Prev = P; } 271 void setNext(MachineBasicBlock *N) { Next = N; } 272 273 // Machine-CFG mutators 274 275 /// addPredecessor - Remove pred as a predecessor of this MachineBasicBlock. 276 /// Don't do this unless you know what you're doing, because it doesn't 277 /// update pred's successors list. Use pred->addSuccessor instead. 278 /// 279 void addPredecessor(MachineBasicBlock *pred); 280 281 /// removePredecessor - Remove pred as a predecessor of this 282 /// MachineBasicBlock. Don't do this unless you know what you're 283 /// doing, because it doesn't update pred's successors list. Use 284 /// pred->removeSuccessor instead. 285 /// 286 void removePredecessor(MachineBasicBlock *pred); 287}; 288 289std::ostream& operator<<(std::ostream &OS, const MachineBasicBlock &MBB); 290 291//===--------------------------------------------------------------------===// 292// GraphTraits specializations for machine basic block graphs (machine-CFGs) 293//===--------------------------------------------------------------------===// 294 295// Provide specializations of GraphTraits to be able to treat a 296// MachineFunction as a graph of MachineBasicBlocks... 297// 298 299template <> struct GraphTraits<MachineBasicBlock *> { 300 typedef MachineBasicBlock NodeType; 301 typedef MachineBasicBlock::succ_iterator ChildIteratorType; 302 303 static NodeType *getEntryNode(MachineBasicBlock *BB) { return BB; } 304 static inline ChildIteratorType child_begin(NodeType *N) { 305 return N->succ_begin(); 306 } 307 static inline ChildIteratorType child_end(NodeType *N) { 308 return N->succ_end(); 309 } 310}; 311 312template <> struct GraphTraits<const MachineBasicBlock *> { 313 typedef const MachineBasicBlock NodeType; 314 typedef MachineBasicBlock::const_succ_iterator ChildIteratorType; 315 316 static NodeType *getEntryNode(const MachineBasicBlock *BB) { return BB; } 317 static inline ChildIteratorType child_begin(NodeType *N) { 318 return N->succ_begin(); 319 } 320 static inline ChildIteratorType child_end(NodeType *N) { 321 return N->succ_end(); 322 } 323}; 324 325// Provide specializations of GraphTraits to be able to treat a 326// MachineFunction as a graph of MachineBasicBlocks... and to walk it 327// in inverse order. Inverse order for a function is considered 328// to be when traversing the predecessor edges of a MBB 329// instead of the successor edges. 330// 331template <> struct GraphTraits<Inverse<MachineBasicBlock*> > { 332 typedef MachineBasicBlock NodeType; 333 typedef MachineBasicBlock::pred_iterator ChildIteratorType; 334 static NodeType *getEntryNode(Inverse<MachineBasicBlock *> G) { 335 return G.Graph; 336 } 337 static inline ChildIteratorType child_begin(NodeType *N) { 338 return N->pred_begin(); 339 } 340 static inline ChildIteratorType child_end(NodeType *N) { 341 return N->pred_end(); 342 } 343}; 344 345template <> struct GraphTraits<Inverse<const MachineBasicBlock*> > { 346 typedef const MachineBasicBlock NodeType; 347 typedef MachineBasicBlock::const_pred_iterator ChildIteratorType; 348 static NodeType *getEntryNode(Inverse<const MachineBasicBlock*> G) { 349 return G.Graph; 350 } 351 static inline ChildIteratorType child_begin(NodeType *N) { 352 return N->pred_begin(); 353 } 354 static inline ChildIteratorType child_end(NodeType *N) { 355 return N->pred_end(); 356 } 357}; 358 359} // End llvm namespace 360 361#endif 362