1 //===-- llvm/CodeGen/MachineFunction.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 native machine code for a function. This class contains a list of 11 // MachineBasicBlock instances that make up the current compiled function. 12 // 13 // This class also contains pointers to various classes which hold 14 // target-specific information about the generated code. 15 // 16 //===----------------------------------------------------------------------===// 17 18 #ifndef LLVM_CODEGEN_MACHINEFUNCTION_H 19 #define LLVM_CODEGEN_MACHINEFUNCTION_H 20 21 #include "llvm/CodeGen/MachineBasicBlock.h" 22 #include "llvm/ADT/ilist.h" 23 #include "llvm/Support/DebugLoc.h" 24 #include "llvm/Support/Allocator.h" 25 #include "llvm/Support/Recycler.h" 26 27 namespace llvm { 28 29 class Value; 30 class Function; 31 class GCModuleInfo; 32 class MachineRegisterInfo; 33 class MachineFrameInfo; 34 class MachineConstantPool; 35 class MachineJumpTableInfo; 36 class MachineModuleInfo; 37 class MCContext; 38 class Pass; 39 class TargetMachine; 40 class TargetRegisterClass; 41 struct MachinePointerInfo; 42 43 template <> 44 struct ilist_traits<MachineBasicBlock> 45 : public ilist_default_traits<MachineBasicBlock> { 46 mutable ilist_half_node<MachineBasicBlock> Sentinel; 47 public: 48 MachineBasicBlock *createSentinel() const { 49 return static_cast<MachineBasicBlock*>(&Sentinel); 50 } 51 void destroySentinel(MachineBasicBlock *) const {} 52 53 MachineBasicBlock *provideInitialHead() const { return createSentinel(); } 54 MachineBasicBlock *ensureHead(MachineBasicBlock*) const { 55 return createSentinel(); 56 } 57 static void noteHead(MachineBasicBlock*, MachineBasicBlock*) {} 58 59 void addNodeToList(MachineBasicBlock* MBB); 60 void removeNodeFromList(MachineBasicBlock* MBB); 61 void deleteNode(MachineBasicBlock *MBB); 62 private: 63 void createNode(const MachineBasicBlock &); 64 }; 65 66 /// MachineFunctionInfo - This class can be derived from and used by targets to 67 /// hold private target-specific information for each MachineFunction. Objects 68 /// of type are accessed/created with MF::getInfo and destroyed when the 69 /// MachineFunction is destroyed. 70 struct MachineFunctionInfo { 71 virtual ~MachineFunctionInfo(); 72 }; 73 74 class MachineFunction { 75 const Function *Fn; 76 const TargetMachine &Target; 77 MCContext &Ctx; 78 MachineModuleInfo &MMI; 79 GCModuleInfo *GMI; 80 81 // RegInfo - Information about each register in use in the function. 82 MachineRegisterInfo *RegInfo; 83 84 // Used to keep track of target-specific per-machine function information for 85 // the target implementation. 86 MachineFunctionInfo *MFInfo; 87 88 // Keep track of objects allocated on the stack. 89 MachineFrameInfo *FrameInfo; 90 91 // Keep track of constants which are spilled to memory 92 MachineConstantPool *ConstantPool; 93 94 // Keep track of jump tables for switch instructions 95 MachineJumpTableInfo *JumpTableInfo; 96 97 // Function-level unique numbering for MachineBasicBlocks. When a 98 // MachineBasicBlock is inserted into a MachineFunction is it automatically 99 // numbered and this vector keeps track of the mapping from ID's to MBB's. 100 std::vector<MachineBasicBlock*> MBBNumbering; 101 102 // Pool-allocate MachineFunction-lifetime and IR objects. 103 BumpPtrAllocator Allocator; 104 105 // Allocation management for instructions in function. 106 Recycler<MachineInstr> InstructionRecycler; 107 108 // Allocation management for basic blocks in function. 109 Recycler<MachineBasicBlock> BasicBlockRecycler; 110 111 // List of machine basic blocks in function 112 typedef ilist<MachineBasicBlock> BasicBlockListType; 113 BasicBlockListType BasicBlocks; 114 115 /// FunctionNumber - This provides a unique ID for each function emitted in 116 /// this translation unit. 117 /// 118 unsigned FunctionNumber; 119 120 /// Alignment - The alignment of the function. 121 unsigned Alignment; 122 123 /// CallsSetJmp - True if the function calls setjmp or sigsetjmp. This is used 124 /// to limit optimizations which cannot reason about the control flow of 125 /// setjmp. 126 bool CallsSetJmp; 127 128 MachineFunction(const MachineFunction &); // DO NOT IMPLEMENT 129 void operator=(const MachineFunction&); // DO NOT IMPLEMENT 130 public: 131 MachineFunction(const Function *Fn, const TargetMachine &TM, 132 unsigned FunctionNum, MachineModuleInfo &MMI, 133 GCModuleInfo* GMI); 134 ~MachineFunction(); 135 136 MachineModuleInfo &getMMI() const { return MMI; } 137 GCModuleInfo *getGMI() const { return GMI; } 138 MCContext &getContext() const { return Ctx; } 139 140 /// getFunction - Return the LLVM function that this machine code represents 141 /// 142 const Function *getFunction() const { return Fn; } 143 144 /// getFunctionNumber - Return a unique ID for the current function. 145 /// 146 unsigned getFunctionNumber() const { return FunctionNumber; } 147 148 /// getTarget - Return the target machine this machine code is compiled with 149 /// 150 const TargetMachine &getTarget() const { return Target; } 151 152 /// getRegInfo - Return information about the registers currently in use. 153 /// 154 MachineRegisterInfo &getRegInfo() { return *RegInfo; } 155 const MachineRegisterInfo &getRegInfo() const { return *RegInfo; } 156 157 /// getFrameInfo - Return the frame info object for the current function. 158 /// This object contains information about objects allocated on the stack 159 /// frame of the current function in an abstract way. 160 /// 161 MachineFrameInfo *getFrameInfo() { return FrameInfo; } 162 const MachineFrameInfo *getFrameInfo() const { return FrameInfo; } 163 164 /// getJumpTableInfo - Return the jump table info object for the current 165 /// function. This object contains information about jump tables in the 166 /// current function. If the current function has no jump tables, this will 167 /// return null. 168 const MachineJumpTableInfo *getJumpTableInfo() const { return JumpTableInfo; } 169 MachineJumpTableInfo *getJumpTableInfo() { return JumpTableInfo; } 170 171 /// getOrCreateJumpTableInfo - Get the JumpTableInfo for this function, if it 172 /// does already exist, allocate one. 173 MachineJumpTableInfo *getOrCreateJumpTableInfo(unsigned JTEntryKind); 174 175 176 /// getConstantPool - Return the constant pool object for the current 177 /// function. 178 /// 179 MachineConstantPool *getConstantPool() { return ConstantPool; } 180 const MachineConstantPool *getConstantPool() const { return ConstantPool; } 181 182 /// getAlignment - Return the alignment (log2, not bytes) of the function. 183 /// 184 unsigned getAlignment() const { return Alignment; } 185 186 /// setAlignment - Set the alignment (log2, not bytes) of the function. 187 /// 188 void setAlignment(unsigned A) { Alignment = A; } 189 190 /// EnsureAlignment - Make sure the function is at least 'A' bits aligned. 191 void EnsureAlignment(unsigned A) { 192 if (Alignment < A) Alignment = A; 193 } 194 195 /// callsSetJmp - Returns true if the function calls setjmp or sigsetjmp. 196 bool callsSetJmp() const { 197 return CallsSetJmp; 198 } 199 200 /// setCallsSetJmp - Set a flag that indicates if there's a call to setjmp or 201 /// sigsetjmp. 202 void setCallsSetJmp(bool B) { 203 CallsSetJmp = B; 204 } 205 206 /// getInfo - Keep track of various per-function pieces of information for 207 /// backends that would like to do so. 208 /// 209 template<typename Ty> 210 Ty *getInfo() { 211 if (!MFInfo) { 212 // This should be just `new (Allocator.Allocate<Ty>()) Ty(*this)', but 213 // that apparently breaks GCC 3.3. 214 Ty *Loc = static_cast<Ty*>(Allocator.Allocate(sizeof(Ty), 215 AlignOf<Ty>::Alignment)); 216 MFInfo = new (Loc) Ty(*this); 217 } 218 return static_cast<Ty*>(MFInfo); 219 } 220 221 template<typename Ty> 222 const Ty *getInfo() const { 223 return const_cast<MachineFunction*>(this)->getInfo<Ty>(); 224 } 225 226 /// getBlockNumbered - MachineBasicBlocks are automatically numbered when they 227 /// are inserted into the machine function. The block number for a machine 228 /// basic block can be found by using the MBB::getBlockNumber method, this 229 /// method provides the inverse mapping. 230 /// 231 MachineBasicBlock *getBlockNumbered(unsigned N) const { 232 assert(N < MBBNumbering.size() && "Illegal block number"); 233 assert(MBBNumbering[N] && "Block was removed from the machine function!"); 234 return MBBNumbering[N]; 235 } 236 237 /// getNumBlockIDs - Return the number of MBB ID's allocated. 238 /// 239 unsigned getNumBlockIDs() const { return (unsigned)MBBNumbering.size(); } 240 241 /// RenumberBlocks - This discards all of the MachineBasicBlock numbers and 242 /// recomputes them. This guarantees that the MBB numbers are sequential, 243 /// dense, and match the ordering of the blocks within the function. If a 244 /// specific MachineBasicBlock is specified, only that block and those after 245 /// it are renumbered. 246 void RenumberBlocks(MachineBasicBlock *MBBFrom = 0); 247 248 /// print - Print out the MachineFunction in a format suitable for debugging 249 /// to the specified stream. 250 /// 251 void print(raw_ostream &OS, SlotIndexes* = 0) const; 252 253 /// viewCFG - This function is meant for use from the debugger. You can just 254 /// say 'call F->viewCFG()' and a ghostview window should pop up from the 255 /// program, displaying the CFG of the current function with the code for each 256 /// basic block inside. This depends on there being a 'dot' and 'gv' program 257 /// in your path. 258 /// 259 void viewCFG() const; 260 261 /// viewCFGOnly - This function is meant for use from the debugger. It works 262 /// just like viewCFG, but it does not include the contents of basic blocks 263 /// into the nodes, just the label. If you are only interested in the CFG 264 /// this can make the graph smaller. 265 /// 266 void viewCFGOnly() const; 267 268 /// dump - Print the current MachineFunction to cerr, useful for debugger use. 269 /// 270 void dump() const; 271 272 /// verify - Run the current MachineFunction through the machine code 273 /// verifier, useful for debugger use. 274 void verify(Pass *p = NULL, const char *Banner = NULL) const; 275 276 // Provide accessors for the MachineBasicBlock list... 277 typedef BasicBlockListType::iterator iterator; 278 typedef BasicBlockListType::const_iterator const_iterator; 279 typedef std::reverse_iterator<const_iterator> const_reverse_iterator; 280 typedef std::reverse_iterator<iterator> reverse_iterator; 281 282 /// addLiveIn - Add the specified physical register as a live-in value and 283 /// create a corresponding virtual register for it. 284 unsigned addLiveIn(unsigned PReg, const TargetRegisterClass *RC); 285 286 //===--------------------------------------------------------------------===// 287 // BasicBlock accessor functions. 288 // 289 iterator begin() { return BasicBlocks.begin(); } 290 const_iterator begin() const { return BasicBlocks.begin(); } 291 iterator end () { return BasicBlocks.end(); } 292 const_iterator end () const { return BasicBlocks.end(); } 293 294 reverse_iterator rbegin() { return BasicBlocks.rbegin(); } 295 const_reverse_iterator rbegin() const { return BasicBlocks.rbegin(); } 296 reverse_iterator rend () { return BasicBlocks.rend(); } 297 const_reverse_iterator rend () const { return BasicBlocks.rend(); } 298 299 unsigned size() const { return (unsigned)BasicBlocks.size();} 300 bool empty() const { return BasicBlocks.empty(); } 301 const MachineBasicBlock &front() const { return BasicBlocks.front(); } 302 MachineBasicBlock &front() { return BasicBlocks.front(); } 303 const MachineBasicBlock & back() const { return BasicBlocks.back(); } 304 MachineBasicBlock & back() { return BasicBlocks.back(); } 305 306 void push_back (MachineBasicBlock *MBB) { BasicBlocks.push_back (MBB); } 307 void push_front(MachineBasicBlock *MBB) { BasicBlocks.push_front(MBB); } 308 void insert(iterator MBBI, MachineBasicBlock *MBB) { 309 BasicBlocks.insert(MBBI, MBB); 310 } 311 void splice(iterator InsertPt, iterator MBBI) { 312 BasicBlocks.splice(InsertPt, BasicBlocks, MBBI); 313 } 314 void splice(iterator InsertPt, iterator MBBI, iterator MBBE) { 315 BasicBlocks.splice(InsertPt, BasicBlocks, MBBI, MBBE); 316 } 317 318 void remove(iterator MBBI) { 319 BasicBlocks.remove(MBBI); 320 } 321 void erase(iterator MBBI) { 322 BasicBlocks.erase(MBBI); 323 } 324 325 //===--------------------------------------------------------------------===// 326 // Internal functions used to automatically number MachineBasicBlocks 327 // 328 329 /// getNextMBBNumber - Returns the next unique number to be assigned 330 /// to a MachineBasicBlock in this MachineFunction. 331 /// 332 unsigned addToMBBNumbering(MachineBasicBlock *MBB) { 333 MBBNumbering.push_back(MBB); 334 return (unsigned)MBBNumbering.size()-1; 335 } 336 337 /// removeFromMBBNumbering - Remove the specific machine basic block from our 338 /// tracker, this is only really to be used by the MachineBasicBlock 339 /// implementation. 340 void removeFromMBBNumbering(unsigned N) { 341 assert(N < MBBNumbering.size() && "Illegal basic block #"); 342 MBBNumbering[N] = 0; 343 } 344 345 /// CreateMachineInstr - Allocate a new MachineInstr. Use this instead 346 /// of `new MachineInstr'. 347 /// 348 MachineInstr *CreateMachineInstr(const MCInstrDesc &MCID, 349 DebugLoc DL, 350 bool NoImp = false); 351 352 /// CloneMachineInstr - Create a new MachineInstr which is a copy of the 353 /// 'Orig' instruction, identical in all ways except the instruction 354 /// has no parent, prev, or next. 355 /// 356 /// See also TargetInstrInfo::duplicate() for target-specific fixes to cloned 357 /// instructions. 358 MachineInstr *CloneMachineInstr(const MachineInstr *Orig); 359 360 /// DeleteMachineInstr - Delete the given MachineInstr. 361 /// 362 void DeleteMachineInstr(MachineInstr *MI); 363 364 /// CreateMachineBasicBlock - Allocate a new MachineBasicBlock. Use this 365 /// instead of `new MachineBasicBlock'. 366 /// 367 MachineBasicBlock *CreateMachineBasicBlock(const BasicBlock *bb = 0); 368 369 /// DeleteMachineBasicBlock - Delete the given MachineBasicBlock. 370 /// 371 void DeleteMachineBasicBlock(MachineBasicBlock *MBB); 372 373 /// getMachineMemOperand - Allocate a new MachineMemOperand. 374 /// MachineMemOperands are owned by the MachineFunction and need not be 375 /// explicitly deallocated. 376 MachineMemOperand *getMachineMemOperand(MachinePointerInfo PtrInfo, 377 unsigned f, uint64_t s, 378 unsigned base_alignment, 379 const MDNode *TBAAInfo = 0); 380 381 /// getMachineMemOperand - Allocate a new MachineMemOperand by copying 382 /// an existing one, adjusting by an offset and using the given size. 383 /// MachineMemOperands are owned by the MachineFunction and need not be 384 /// explicitly deallocated. 385 MachineMemOperand *getMachineMemOperand(const MachineMemOperand *MMO, 386 int64_t Offset, uint64_t Size); 387 388 /// allocateMemRefsArray - Allocate an array to hold MachineMemOperand 389 /// pointers. This array is owned by the MachineFunction. 390 MachineInstr::mmo_iterator allocateMemRefsArray(unsigned long Num); 391 392 /// extractLoadMemRefs - Allocate an array and populate it with just the 393 /// load information from the given MachineMemOperand sequence. 394 std::pair<MachineInstr::mmo_iterator, 395 MachineInstr::mmo_iterator> 396 extractLoadMemRefs(MachineInstr::mmo_iterator Begin, 397 MachineInstr::mmo_iterator End); 398 399 /// extractStoreMemRefs - Allocate an array and populate it with just the 400 /// store information from the given MachineMemOperand sequence. 401 std::pair<MachineInstr::mmo_iterator, 402 MachineInstr::mmo_iterator> 403 extractStoreMemRefs(MachineInstr::mmo_iterator Begin, 404 MachineInstr::mmo_iterator End); 405 406 //===--------------------------------------------------------------------===// 407 // Label Manipulation. 408 // 409 410 /// getJTISymbol - Return the MCSymbol for the specified non-empty jump table. 411 /// If isLinkerPrivate is specified, an 'l' label is returned, otherwise a 412 /// normal 'L' label is returned. 413 MCSymbol *getJTISymbol(unsigned JTI, MCContext &Ctx, 414 bool isLinkerPrivate = false) const; 415 416 /// getPICBaseSymbol - Return a function-local symbol to represent the PIC 417 /// base. 418 MCSymbol *getPICBaseSymbol() const; 419 }; 420 421 //===--------------------------------------------------------------------===// 422 // GraphTraits specializations for function basic block graphs (CFGs) 423 //===--------------------------------------------------------------------===// 424 425 // Provide specializations of GraphTraits to be able to treat a 426 // machine function as a graph of machine basic blocks... these are 427 // the same as the machine basic block iterators, except that the root 428 // node is implicitly the first node of the function. 429 // 430 template <> struct GraphTraits<MachineFunction*> : 431 public GraphTraits<MachineBasicBlock*> { 432 static NodeType *getEntryNode(MachineFunction *F) { 433 return &F->front(); 434 } 435 436 // nodes_iterator/begin/end - Allow iteration over all nodes in the graph 437 typedef MachineFunction::iterator nodes_iterator; 438 static nodes_iterator nodes_begin(MachineFunction *F) { return F->begin(); } 439 static nodes_iterator nodes_end (MachineFunction *F) { return F->end(); } 440 }; 441 template <> struct GraphTraits<const MachineFunction*> : 442 public GraphTraits<const MachineBasicBlock*> { 443 static NodeType *getEntryNode(const MachineFunction *F) { 444 return &F->front(); 445 } 446 447 // nodes_iterator/begin/end - Allow iteration over all nodes in the graph 448 typedef MachineFunction::const_iterator nodes_iterator; 449 static nodes_iterator nodes_begin(const MachineFunction *F) { 450 return F->begin(); 451 } 452 static nodes_iterator nodes_end (const MachineFunction *F) { 453 return F->end(); 454 } 455 }; 456 457 458 // Provide specializations of GraphTraits to be able to treat a function as a 459 // graph of basic blocks... and to walk it in inverse order. Inverse order for 460 // a function is considered to be when traversing the predecessor edges of a BB 461 // instead of the successor edges. 462 // 463 template <> struct GraphTraits<Inverse<MachineFunction*> > : 464 public GraphTraits<Inverse<MachineBasicBlock*> > { 465 static NodeType *getEntryNode(Inverse<MachineFunction*> G) { 466 return &G.Graph->front(); 467 } 468 }; 469 template <> struct GraphTraits<Inverse<const MachineFunction*> > : 470 public GraphTraits<Inverse<const MachineBasicBlock*> > { 471 static NodeType *getEntryNode(Inverse<const MachineFunction *> G) { 472 return &G.Graph->front(); 473 } 474 }; 475 476 } // End llvm namespace 477 478 #endif 479