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/ADT/ilist.h" 22#include "llvm/CodeGen/MachineBasicBlock.h" 23#include "llvm/Support/Allocator.h" 24#include "llvm/Support/ArrayRecycler.h" 25#include "llvm/Support/DebugLoc.h" 26#include "llvm/Support/Recycler.h" 27 28namespace llvm { 29 30class Value; 31class Function; 32class GCModuleInfo; 33class MachineRegisterInfo; 34class MachineFrameInfo; 35class MachineConstantPool; 36class MachineJumpTableInfo; 37class MachineModuleInfo; 38class MCContext; 39class Pass; 40class TargetMachine; 41class TargetRegisterClass; 42struct MachinePointerInfo; 43 44template <> 45struct ilist_traits<MachineBasicBlock> 46 : public ilist_default_traits<MachineBasicBlock> { 47 mutable ilist_half_node<MachineBasicBlock> Sentinel; 48public: 49 MachineBasicBlock *createSentinel() const { 50 return static_cast<MachineBasicBlock*>(&Sentinel); 51 } 52 void destroySentinel(MachineBasicBlock *) const {} 53 54 MachineBasicBlock *provideInitialHead() const { return createSentinel(); } 55 MachineBasicBlock *ensureHead(MachineBasicBlock*) const { 56 return createSentinel(); 57 } 58 static void noteHead(MachineBasicBlock*, MachineBasicBlock*) {} 59 60 void addNodeToList(MachineBasicBlock* MBB); 61 void removeNodeFromList(MachineBasicBlock* MBB); 62 void deleteNode(MachineBasicBlock *MBB); 63private: 64 void createNode(const MachineBasicBlock &); 65}; 66 67/// MachineFunctionInfo - This class can be derived from and used by targets to 68/// hold private target-specific information for each MachineFunction. Objects 69/// of type are accessed/created with MF::getInfo and destroyed when the 70/// MachineFunction is destroyed. 71struct MachineFunctionInfo { 72 virtual ~MachineFunctionInfo(); 73}; 74 75class MachineFunction { 76 const Function *Fn; 77 const TargetMachine &Target; 78 MCContext &Ctx; 79 MachineModuleInfo &MMI; 80 GCModuleInfo *GMI; 81 82 // RegInfo - Information about each register in use in the function. 83 MachineRegisterInfo *RegInfo; 84 85 // Used to keep track of target-specific per-machine function information for 86 // the target implementation. 87 MachineFunctionInfo *MFInfo; 88 89 // Keep track of objects allocated on the stack. 90 MachineFrameInfo *FrameInfo; 91 92 // Keep track of constants which are spilled to memory 93 MachineConstantPool *ConstantPool; 94 95 // Keep track of jump tables for switch instructions 96 MachineJumpTableInfo *JumpTableInfo; 97 98 // Function-level unique numbering for MachineBasicBlocks. When a 99 // MachineBasicBlock is inserted into a MachineFunction is it automatically 100 // numbered and this vector keeps track of the mapping from ID's to MBB's. 101 std::vector<MachineBasicBlock*> MBBNumbering; 102 103 // Pool-allocate MachineFunction-lifetime and IR objects. 104 BumpPtrAllocator Allocator; 105 106 // Allocation management for instructions in function. 107 Recycler<MachineInstr> InstructionRecycler; 108 109 // Allocation management for operand arrays on instructions. 110 ArrayRecycler<MachineOperand> OperandRecycler; 111 112 // Allocation management for basic blocks in function. 113 Recycler<MachineBasicBlock> BasicBlockRecycler; 114 115 // List of machine basic blocks in function 116 typedef ilist<MachineBasicBlock> BasicBlockListType; 117 BasicBlockListType BasicBlocks; 118 119 /// FunctionNumber - This provides a unique ID for each function emitted in 120 /// this translation unit. 121 /// 122 unsigned FunctionNumber; 123 124 /// Alignment - The alignment of the function. 125 unsigned Alignment; 126 127 /// ExposesReturnsTwice - True if the function calls setjmp or related 128 /// functions with attribute "returns twice", but doesn't have 129 /// the attribute itself. 130 /// This is used to limit optimizations which cannot reason 131 /// about the control flow of such functions. 132 bool ExposesReturnsTwice; 133 134 /// True if the function includes any inline assembly. 135 bool HasInlineAsm; 136 137 MachineFunction(const MachineFunction &) LLVM_DELETED_FUNCTION; 138 void operator=(const MachineFunction&) LLVM_DELETED_FUNCTION; 139public: 140 MachineFunction(const Function *Fn, const TargetMachine &TM, 141 unsigned FunctionNum, MachineModuleInfo &MMI, 142 GCModuleInfo* GMI); 143 ~MachineFunction(); 144 145 MachineModuleInfo &getMMI() const { return MMI; } 146 GCModuleInfo *getGMI() const { return GMI; } 147 MCContext &getContext() const { return Ctx; } 148 149 /// getFunction - Return the LLVM function that this machine code represents 150 /// 151 const Function *getFunction() const { return Fn; } 152 153 /// getName - Return the name of the corresponding LLVM function. 154 /// 155 StringRef getName() const; 156 157 /// getFunctionNumber - Return a unique ID for the current function. 158 /// 159 unsigned getFunctionNumber() const { return FunctionNumber; } 160 161 /// getTarget - Return the target machine this machine code is compiled with 162 /// 163 const TargetMachine &getTarget() const { return Target; } 164 165 /// getRegInfo - Return information about the registers currently in use. 166 /// 167 MachineRegisterInfo &getRegInfo() { return *RegInfo; } 168 const MachineRegisterInfo &getRegInfo() const { return *RegInfo; } 169 170 /// getFrameInfo - Return the frame info object for the current function. 171 /// This object contains information about objects allocated on the stack 172 /// frame of the current function in an abstract way. 173 /// 174 MachineFrameInfo *getFrameInfo() { return FrameInfo; } 175 const MachineFrameInfo *getFrameInfo() const { return FrameInfo; } 176 177 /// getJumpTableInfo - Return the jump table info object for the current 178 /// function. This object contains information about jump tables in the 179 /// current function. If the current function has no jump tables, this will 180 /// return null. 181 const MachineJumpTableInfo *getJumpTableInfo() const { return JumpTableInfo; } 182 MachineJumpTableInfo *getJumpTableInfo() { return JumpTableInfo; } 183 184 /// getOrCreateJumpTableInfo - Get the JumpTableInfo for this function, if it 185 /// does already exist, allocate one. 186 MachineJumpTableInfo *getOrCreateJumpTableInfo(unsigned JTEntryKind); 187 188 189 /// getConstantPool - Return the constant pool object for the current 190 /// function. 191 /// 192 MachineConstantPool *getConstantPool() { return ConstantPool; } 193 const MachineConstantPool *getConstantPool() const { return ConstantPool; } 194 195 /// getAlignment - Return the alignment (log2, not bytes) of the function. 196 /// 197 unsigned getAlignment() const { return Alignment; } 198 199 /// setAlignment - Set the alignment (log2, not bytes) of the function. 200 /// 201 void setAlignment(unsigned A) { Alignment = A; } 202 203 /// ensureAlignment - Make sure the function is at least 1 << A bytes aligned. 204 void ensureAlignment(unsigned A) { 205 if (Alignment < A) Alignment = A; 206 } 207 208 /// exposesReturnsTwice - Returns true if the function calls setjmp or 209 /// any other similar functions with attribute "returns twice" without 210 /// having the attribute itself. 211 bool exposesReturnsTwice() const { 212 return ExposesReturnsTwice; 213 } 214 215 /// setCallsSetJmp - Set a flag that indicates if there's a call to 216 /// a "returns twice" function. 217 void setExposesReturnsTwice(bool B) { 218 ExposesReturnsTwice = B; 219 } 220 221 /// Returns true if the function contains any inline assembly. 222 bool hasInlineAsm() const { 223 return HasInlineAsm; 224 } 225 226 /// Set a flag that indicates that the function contains inline assembly. 227 void setHasInlineAsm(bool B) { 228 HasInlineAsm = B; 229 } 230 231 /// getInfo - Keep track of various per-function pieces of information for 232 /// backends that would like to do so. 233 /// 234 template<typename Ty> 235 Ty *getInfo() { 236 if (!MFInfo) { 237 // This should be just `new (Allocator.Allocate<Ty>()) Ty(*this)', but 238 // that apparently breaks GCC 3.3. 239 Ty *Loc = static_cast<Ty*>(Allocator.Allocate(sizeof(Ty), 240 AlignOf<Ty>::Alignment)); 241 MFInfo = new (Loc) Ty(*this); 242 } 243 return static_cast<Ty*>(MFInfo); 244 } 245 246 template<typename Ty> 247 const Ty *getInfo() const { 248 return const_cast<MachineFunction*>(this)->getInfo<Ty>(); 249 } 250 251 /// getBlockNumbered - MachineBasicBlocks are automatically numbered when they 252 /// are inserted into the machine function. The block number for a machine 253 /// basic block can be found by using the MBB::getBlockNumber method, this 254 /// method provides the inverse mapping. 255 /// 256 MachineBasicBlock *getBlockNumbered(unsigned N) const { 257 assert(N < MBBNumbering.size() && "Illegal block number"); 258 assert(MBBNumbering[N] && "Block was removed from the machine function!"); 259 return MBBNumbering[N]; 260 } 261 262 /// getNumBlockIDs - Return the number of MBB ID's allocated. 263 /// 264 unsigned getNumBlockIDs() const { return (unsigned)MBBNumbering.size(); } 265 266 /// RenumberBlocks - This discards all of the MachineBasicBlock numbers and 267 /// recomputes them. This guarantees that the MBB numbers are sequential, 268 /// dense, and match the ordering of the blocks within the function. If a 269 /// specific MachineBasicBlock is specified, only that block and those after 270 /// it are renumbered. 271 void RenumberBlocks(MachineBasicBlock *MBBFrom = 0); 272 273 /// print - Print out the MachineFunction in a format suitable for debugging 274 /// to the specified stream. 275 /// 276 void print(raw_ostream &OS, SlotIndexes* = 0) const; 277 278 /// viewCFG - This function is meant for use from the debugger. You can just 279 /// say 'call F->viewCFG()' and a ghostview window should pop up from the 280 /// program, displaying the CFG of the current function with the code for each 281 /// basic block inside. This depends on there being a 'dot' and 'gv' program 282 /// in your path. 283 /// 284 void viewCFG() const; 285 286 /// viewCFGOnly - This function is meant for use from the debugger. It works 287 /// just like viewCFG, but it does not include the contents of basic blocks 288 /// into the nodes, just the label. If you are only interested in the CFG 289 /// this can make the graph smaller. 290 /// 291 void viewCFGOnly() const; 292 293 /// dump - Print the current MachineFunction to cerr, useful for debugger use. 294 /// 295 void dump() const; 296 297 /// verify - Run the current MachineFunction through the machine code 298 /// verifier, useful for debugger use. 299 void verify(Pass *p = NULL, const char *Banner = NULL) const; 300 301 // Provide accessors for the MachineBasicBlock list... 302 typedef BasicBlockListType::iterator iterator; 303 typedef BasicBlockListType::const_iterator const_iterator; 304 typedef std::reverse_iterator<const_iterator> const_reverse_iterator; 305 typedef std::reverse_iterator<iterator> reverse_iterator; 306 307 /// addLiveIn - Add the specified physical register as a live-in value and 308 /// create a corresponding virtual register for it. 309 unsigned addLiveIn(unsigned PReg, const TargetRegisterClass *RC); 310 311 //===--------------------------------------------------------------------===// 312 // BasicBlock accessor functions. 313 // 314 iterator begin() { return BasicBlocks.begin(); } 315 const_iterator begin() const { return BasicBlocks.begin(); } 316 iterator end () { return BasicBlocks.end(); } 317 const_iterator end () const { return BasicBlocks.end(); } 318 319 reverse_iterator rbegin() { return BasicBlocks.rbegin(); } 320 const_reverse_iterator rbegin() const { return BasicBlocks.rbegin(); } 321 reverse_iterator rend () { return BasicBlocks.rend(); } 322 const_reverse_iterator rend () const { return BasicBlocks.rend(); } 323 324 unsigned size() const { return (unsigned)BasicBlocks.size();} 325 bool empty() const { return BasicBlocks.empty(); } 326 const MachineBasicBlock &front() const { return BasicBlocks.front(); } 327 MachineBasicBlock &front() { return BasicBlocks.front(); } 328 const MachineBasicBlock & back() const { return BasicBlocks.back(); } 329 MachineBasicBlock & back() { return BasicBlocks.back(); } 330 331 void push_back (MachineBasicBlock *MBB) { BasicBlocks.push_back (MBB); } 332 void push_front(MachineBasicBlock *MBB) { BasicBlocks.push_front(MBB); } 333 void insert(iterator MBBI, MachineBasicBlock *MBB) { 334 BasicBlocks.insert(MBBI, MBB); 335 } 336 void splice(iterator InsertPt, iterator MBBI) { 337 BasicBlocks.splice(InsertPt, BasicBlocks, MBBI); 338 } 339 void splice(iterator InsertPt, iterator MBBI, iterator MBBE) { 340 BasicBlocks.splice(InsertPt, BasicBlocks, MBBI, MBBE); 341 } 342 343 void remove(iterator MBBI) { 344 BasicBlocks.remove(MBBI); 345 } 346 void erase(iterator MBBI) { 347 BasicBlocks.erase(MBBI); 348 } 349 350 //===--------------------------------------------------------------------===// 351 // Internal functions used to automatically number MachineBasicBlocks 352 // 353 354 /// \brief Adds the MBB to the internal numbering. Returns the unique number 355 /// assigned to the MBB. 356 /// 357 unsigned addToMBBNumbering(MachineBasicBlock *MBB) { 358 MBBNumbering.push_back(MBB); 359 return (unsigned)MBBNumbering.size()-1; 360 } 361 362 /// removeFromMBBNumbering - Remove the specific machine basic block from our 363 /// tracker, this is only really to be used by the MachineBasicBlock 364 /// implementation. 365 void removeFromMBBNumbering(unsigned N) { 366 assert(N < MBBNumbering.size() && "Illegal basic block #"); 367 MBBNumbering[N] = 0; 368 } 369 370 /// CreateMachineInstr - Allocate a new MachineInstr. Use this instead 371 /// of `new MachineInstr'. 372 /// 373 MachineInstr *CreateMachineInstr(const MCInstrDesc &MCID, 374 DebugLoc DL, 375 bool NoImp = false); 376 377 /// CloneMachineInstr - Create a new MachineInstr which is a copy of the 378 /// 'Orig' instruction, identical in all ways except the instruction 379 /// has no parent, prev, or next. 380 /// 381 /// See also TargetInstrInfo::duplicate() for target-specific fixes to cloned 382 /// instructions. 383 MachineInstr *CloneMachineInstr(const MachineInstr *Orig); 384 385 /// DeleteMachineInstr - Delete the given MachineInstr. 386 /// 387 void DeleteMachineInstr(MachineInstr *MI); 388 389 /// CreateMachineBasicBlock - Allocate a new MachineBasicBlock. Use this 390 /// instead of `new MachineBasicBlock'. 391 /// 392 MachineBasicBlock *CreateMachineBasicBlock(const BasicBlock *bb = 0); 393 394 /// DeleteMachineBasicBlock - Delete the given MachineBasicBlock. 395 /// 396 void DeleteMachineBasicBlock(MachineBasicBlock *MBB); 397 398 /// getMachineMemOperand - Allocate a new MachineMemOperand. 399 /// MachineMemOperands are owned by the MachineFunction and need not be 400 /// explicitly deallocated. 401 MachineMemOperand *getMachineMemOperand(MachinePointerInfo PtrInfo, 402 unsigned f, uint64_t s, 403 unsigned base_alignment, 404 const MDNode *TBAAInfo = 0, 405 const MDNode *Ranges = 0); 406 407 /// getMachineMemOperand - Allocate a new MachineMemOperand by copying 408 /// an existing one, adjusting by an offset and using the given size. 409 /// MachineMemOperands are owned by the MachineFunction and need not be 410 /// explicitly deallocated. 411 MachineMemOperand *getMachineMemOperand(const MachineMemOperand *MMO, 412 int64_t Offset, uint64_t Size); 413 414 typedef ArrayRecycler<MachineOperand>::Capacity OperandCapacity; 415 416 /// Allocate an array of MachineOperands. This is only intended for use by 417 /// internal MachineInstr functions. 418 MachineOperand *allocateOperandArray(OperandCapacity Cap) { 419 return OperandRecycler.allocate(Cap, Allocator); 420 } 421 422 /// Dellocate an array of MachineOperands and recycle the memory. This is 423 /// only intended for use by internal MachineInstr functions. 424 /// Cap must be the same capacity that was used to allocate the array. 425 void deallocateOperandArray(OperandCapacity Cap, MachineOperand *Array) { 426 OperandRecycler.deallocate(Cap, Array); 427 } 428 429 /// allocateMemRefsArray - Allocate an array to hold MachineMemOperand 430 /// pointers. This array is owned by the MachineFunction. 431 MachineInstr::mmo_iterator allocateMemRefsArray(unsigned long Num); 432 433 /// extractLoadMemRefs - Allocate an array and populate it with just the 434 /// load information from the given MachineMemOperand sequence. 435 std::pair<MachineInstr::mmo_iterator, 436 MachineInstr::mmo_iterator> 437 extractLoadMemRefs(MachineInstr::mmo_iterator Begin, 438 MachineInstr::mmo_iterator End); 439 440 /// extractStoreMemRefs - Allocate an array and populate it with just the 441 /// store information from the given MachineMemOperand sequence. 442 std::pair<MachineInstr::mmo_iterator, 443 MachineInstr::mmo_iterator> 444 extractStoreMemRefs(MachineInstr::mmo_iterator Begin, 445 MachineInstr::mmo_iterator End); 446 447 //===--------------------------------------------------------------------===// 448 // Label Manipulation. 449 // 450 451 /// getJTISymbol - Return the MCSymbol for the specified non-empty jump table. 452 /// If isLinkerPrivate is specified, an 'l' label is returned, otherwise a 453 /// normal 'L' label is returned. 454 MCSymbol *getJTISymbol(unsigned JTI, MCContext &Ctx, 455 bool isLinkerPrivate = false) const; 456 457 /// getPICBaseSymbol - Return a function-local symbol to represent the PIC 458 /// base. 459 MCSymbol *getPICBaseSymbol() const; 460}; 461 462//===--------------------------------------------------------------------===// 463// GraphTraits specializations for function basic block graphs (CFGs) 464//===--------------------------------------------------------------------===// 465 466// Provide specializations of GraphTraits to be able to treat a 467// machine function as a graph of machine basic blocks... these are 468// the same as the machine basic block iterators, except that the root 469// node is implicitly the first node of the function. 470// 471template <> struct GraphTraits<MachineFunction*> : 472 public GraphTraits<MachineBasicBlock*> { 473 static NodeType *getEntryNode(MachineFunction *F) { 474 return &F->front(); 475 } 476 477 // nodes_iterator/begin/end - Allow iteration over all nodes in the graph 478 typedef MachineFunction::iterator nodes_iterator; 479 static nodes_iterator nodes_begin(MachineFunction *F) { return F->begin(); } 480 static nodes_iterator nodes_end (MachineFunction *F) { return F->end(); } 481 static unsigned size (MachineFunction *F) { return F->size(); } 482}; 483template <> struct GraphTraits<const MachineFunction*> : 484 public GraphTraits<const MachineBasicBlock*> { 485 static NodeType *getEntryNode(const MachineFunction *F) { 486 return &F->front(); 487 } 488 489 // nodes_iterator/begin/end - Allow iteration over all nodes in the graph 490 typedef MachineFunction::const_iterator nodes_iterator; 491 static nodes_iterator nodes_begin(const MachineFunction *F) { 492 return F->begin(); 493 } 494 static nodes_iterator nodes_end (const MachineFunction *F) { 495 return F->end(); 496 } 497 static unsigned size (const MachineFunction *F) { 498 return F->size(); 499 } 500}; 501 502 503// Provide specializations of GraphTraits to be able to treat a function as a 504// graph of basic blocks... and to walk it in inverse order. Inverse order for 505// a function is considered to be when traversing the predecessor edges of a BB 506// instead of the successor edges. 507// 508template <> struct GraphTraits<Inverse<MachineFunction*> > : 509 public GraphTraits<Inverse<MachineBasicBlock*> > { 510 static NodeType *getEntryNode(Inverse<MachineFunction*> G) { 511 return &G.Graph->front(); 512 } 513}; 514template <> struct GraphTraits<Inverse<const MachineFunction*> > : 515 public GraphTraits<Inverse<const MachineBasicBlock*> > { 516 static NodeType *getEntryNode(Inverse<const MachineFunction *> G) { 517 return &G.Graph->front(); 518 } 519}; 520 521} // End llvm namespace 522 523#endif 524