1 //===-- MachineFunction.cpp -----------------------------------------------===// 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 information for a function. This allows 11 // target-specific information about the generated code to be stored with each 12 // function. 13 // 14 //===----------------------------------------------------------------------===// 15 16 #include "llvm/DerivedTypes.h" 17 #include "llvm/CodeGen/MachineConstantPool.h" 18 #include "llvm/CodeGen/MachineFunctionPass.h" 19 #include "llvm/CodeGen/MachineFrameInfo.h" 20 #include "llvm/CodeGen/MachineInstr.h" 21 #include "llvm/CodeGen/MachineJumpTableInfo.h" 22 #include "llvm/CodeGen/MachineRegisterInfo.h" 23 #include "llvm/CodeGen/Passes.h" 24 #include "llvm/Target/TargetData.h" 25 #include "llvm/Target/TargetLowering.h" 26 #include "llvm/Target/TargetMachine.h" 27 #include "llvm/Target/TargetFrameInfo.h" 28 #include "llvm/Function.h" 29 #include "llvm/Instructions.h" 30 #include "llvm/Support/Compiler.h" 31 #include "llvm/Support/GraphWriter.h" 32 #include "llvm/ADT/STLExtras.h" 33 #include "llvm/Config/config.h" 34 #include <fstream> 35 #include <sstream> 36 using namespace llvm; 37 38 static AnnotationID MF_AID( 39 AnnotationManager::getID("CodeGen::MachineCodeForFunction")); 40 41 // Out of line virtual function to home classes. 42 void MachineFunctionPass::virtfn() {} 43 44 namespace { 45 struct VISIBILITY_HIDDEN Printer : public MachineFunctionPass { 46 static char ID; 47 48 std::ostream *OS; 49 const std::string Banner; 50 51 Printer (std::ostream *_OS, const std::string &_Banner) 52 : MachineFunctionPass((intptr_t)&ID), OS (_OS), Banner (_Banner) { } 53 54 const char *getPassName() const { return "MachineFunction Printer"; } 55 56 virtual void getAnalysisUsage(AnalysisUsage &AU) const { 57 AU.setPreservesAll(); 58 } 59 60 bool runOnMachineFunction(MachineFunction &MF) { 61 (*OS) << Banner; 62 MF.print (*OS); 63 return false; 64 } 65 }; 66 char Printer::ID = 0; 67 } 68 69 /// Returns a newly-created MachineFunction Printer pass. The default output 70 /// stream is std::cerr; the default banner is empty. 71 /// 72 FunctionPass *llvm::createMachineFunctionPrinterPass(std::ostream *OS, 73 const std::string &Banner){ 74 return new Printer(OS, Banner); 75 } 76 77 namespace { 78 struct VISIBILITY_HIDDEN Deleter : public MachineFunctionPass { 79 static char ID; 80 Deleter() : MachineFunctionPass((intptr_t)&ID) {} 81 82 const char *getPassName() const { return "Machine Code Deleter"; } 83 84 bool runOnMachineFunction(MachineFunction &MF) { 85 // Delete the annotation from the function now. 86 MachineFunction::destruct(MF.getFunction()); 87 return true; 88 } 89 }; 90 char Deleter::ID = 0; 91 } 92 93 /// MachineCodeDeletion Pass - This pass deletes all of the machine code for 94 /// the current function, which should happen after the function has been 95 /// emitted to a .s file or to memory. 96 FunctionPass *llvm::createMachineCodeDeleter() { 97 return new Deleter(); 98 } 99 100 101 102 //===---------------------------------------------------------------------===// 103 // MachineFunction implementation 104 //===---------------------------------------------------------------------===// 105 106 void alist_traits<MachineBasicBlock>::deleteNode(MachineBasicBlock *MBB) { 107 MBB->getParent()->DeleteMachineBasicBlock(MBB); 108 } 109 110 MachineFunction::MachineFunction(const Function *F, 111 const TargetMachine &TM) 112 : Annotation(MF_AID), Fn(F), Target(TM) { 113 RegInfo = new (Allocator.Allocate<MachineRegisterInfo>()) 114 MachineRegisterInfo(*TM.getRegisterInfo()); 115 MFInfo = 0; 116 FrameInfo = new (Allocator.Allocate<MachineFrameInfo>()) 117 MachineFrameInfo(*TM.getFrameInfo()); 118 ConstantPool = new (Allocator.Allocate<MachineConstantPool>()) 119 MachineConstantPool(TM.getTargetData()); 120 121 // Set up jump table. 122 const TargetData &TD = *TM.getTargetData(); 123 bool IsPic = TM.getRelocationModel() == Reloc::PIC_; 124 unsigned EntrySize = IsPic ? 4 : TD.getPointerSize(); 125 unsigned Alignment = IsPic ? TD.getABITypeAlignment(Type::Int32Ty) 126 : TD.getPointerABIAlignment(); 127 JumpTableInfo = new (Allocator.Allocate<MachineJumpTableInfo>()) 128 MachineJumpTableInfo(EntrySize, Alignment); 129 } 130 131 MachineFunction::~MachineFunction() { 132 BasicBlocks.clear(); 133 InstructionRecycler.clear(Allocator); 134 BasicBlockRecycler.clear(Allocator); 135 MemOperandRecycler.clear(Allocator); 136 RegInfo->~MachineRegisterInfo(); Allocator.Deallocate(RegInfo); 137 if (MFInfo) { 138 MFInfo->~MachineFunctionInfo(); Allocator.Deallocate(MFInfo); 139 } 140 FrameInfo->~MachineFrameInfo(); Allocator.Deallocate(FrameInfo); 141 ConstantPool->~MachineConstantPool(); Allocator.Deallocate(ConstantPool); 142 JumpTableInfo->~MachineJumpTableInfo(); Allocator.Deallocate(JumpTableInfo); 143 } 144 145 146 /// RenumberBlocks - This discards all of the MachineBasicBlock numbers and 147 /// recomputes them. This guarantees that the MBB numbers are sequential, 148 /// dense, and match the ordering of the blocks within the function. If a 149 /// specific MachineBasicBlock is specified, only that block and those after 150 /// it are renumbered. 151 void MachineFunction::RenumberBlocks(MachineBasicBlock *MBB) { 152 if (empty()) { MBBNumbering.clear(); return; } 153 MachineFunction::iterator MBBI, E = end(); 154 if (MBB == 0) 155 MBBI = begin(); 156 else 157 MBBI = MBB; 158 159 // Figure out the block number this should have. 160 unsigned BlockNo = 0; 161 if (MBBI != begin()) 162 BlockNo = prior(MBBI)->getNumber()+1; 163 164 for (; MBBI != E; ++MBBI, ++BlockNo) { 165 if (MBBI->getNumber() != (int)BlockNo) { 166 // Remove use of the old number. 167 if (MBBI->getNumber() != -1) { 168 assert(MBBNumbering[MBBI->getNumber()] == &*MBBI && 169 "MBB number mismatch!"); 170 MBBNumbering[MBBI->getNumber()] = 0; 171 } 172 173 // If BlockNo is already taken, set that block's number to -1. 174 if (MBBNumbering[BlockNo]) 175 MBBNumbering[BlockNo]->setNumber(-1); 176 177 MBBNumbering[BlockNo] = MBBI; 178 MBBI->setNumber(BlockNo); 179 } 180 } 181 182 // Okay, all the blocks are renumbered. If we have compactified the block 183 // numbering, shrink MBBNumbering now. 184 assert(BlockNo <= MBBNumbering.size() && "Mismatch!"); 185 MBBNumbering.resize(BlockNo); 186 } 187 188 /// CreateMachineInstr - Allocate a new MachineInstr. Use this instead 189 /// of `new MachineInstr'. 190 /// 191 MachineInstr * 192 MachineFunction::CreateMachineInstr(const TargetInstrDesc &TID, bool NoImp) { 193 return new (InstructionRecycler.Allocate<MachineInstr>(Allocator)) 194 MachineInstr(TID, NoImp); 195 } 196 197 /// CloneMachineInstr - Create a new MachineInstr which is a copy of the 198 /// 'Orig' instruction, identical in all ways except the the instruction 199 /// has no parent, prev, or next. 200 /// 201 MachineInstr * 202 MachineFunction::CloneMachineInstr(const MachineInstr *Orig) { 203 return new (InstructionRecycler.Allocate<MachineInstr>(Allocator)) 204 MachineInstr(*this, *Orig); 205 } 206 207 /// DeleteMachineInstr - Delete the given MachineInstr. 208 /// 209 void 210 MachineFunction::DeleteMachineInstr(MachineInstr *MI) { 211 // Clear the instructions memoperands. This must be done manually because 212 // the instruction's parent pointer is now null, so it can't properly 213 // deallocate them on its own. 214 MI->clearMemOperands(*this); 215 216 MI->~MachineInstr(); 217 InstructionRecycler.Deallocate(Allocator, MI); 218 } 219 220 /// CreateMachineBasicBlock - Allocate a new MachineBasicBlock. Use this 221 /// instead of `new MachineBasicBlock'. 222 /// 223 MachineBasicBlock * 224 MachineFunction::CreateMachineBasicBlock(const BasicBlock *bb) { 225 return new (BasicBlockRecycler.Allocate<MachineBasicBlock>(Allocator)) 226 MachineBasicBlock(*this, bb); 227 } 228 229 /// DeleteMachineBasicBlock - Delete the given MachineBasicBlock. 230 /// 231 void 232 MachineFunction::DeleteMachineBasicBlock(MachineBasicBlock *MBB) { 233 assert(MBB->getParent() == this && "MBB parent mismatch!"); 234 MBB->~MachineBasicBlock(); 235 BasicBlockRecycler.Deallocate(Allocator, MBB); 236 } 237 238 /// CreateMachineMemOperand - Allocate a new MachineMemOperand. Use this 239 /// instead of `new MachineMemOperand'. 240 /// 241 MachineMemOperand * 242 MachineFunction::CreateMachineMemOperand(const MachineMemOperand &MMO) { 243 return new (MemOperandRecycler.Allocate<MachineMemOperand>(Allocator)) 244 MachineMemOperand(MMO); 245 } 246 247 /// DeleteMachineMemOperand - Delete the given MachineMemOperand. 248 /// 249 void 250 MachineFunction::DeleteMachineMemOperand(MachineMemOperand *MO) { 251 MO->~MachineMemOperand(); 252 MemOperandRecycler.Deallocate(Allocator, MO); 253 } 254 255 void MachineFunction::dump() const { 256 print(*cerr.stream()); 257 } 258 259 void MachineFunction::print(std::ostream &OS) const { 260 OS << "# Machine code for " << Fn->getName () << "():\n"; 261 262 // Print Frame Information 263 FrameInfo->print(*this, OS); 264 265 // Print JumpTable Information 266 JumpTableInfo->print(OS); 267 268 // Print Constant Pool 269 ConstantPool->print(OS); 270 271 const TargetRegisterInfo *TRI = getTarget().getRegisterInfo(); 272 273 if (!RegInfo->livein_empty()) { 274 OS << "Live Ins:"; 275 for (MachineRegisterInfo::livein_iterator 276 I = RegInfo->livein_begin(), E = RegInfo->livein_end(); I != E; ++I) { 277 if (TRI) 278 OS << " " << TRI->getName(I->first); 279 else 280 OS << " Reg #" << I->first; 281 282 if (I->second) 283 OS << " in VR#" << I->second << " "; 284 } 285 OS << "\n"; 286 } 287 if (!RegInfo->liveout_empty()) { 288 OS << "Live Outs:"; 289 for (MachineRegisterInfo::liveout_iterator 290 I = RegInfo->liveout_begin(), E = RegInfo->liveout_end(); I != E; ++I) 291 if (TRI) 292 OS << " " << TRI->getName(*I); 293 else 294 OS << " Reg #" << *I; 295 OS << "\n"; 296 } 297 298 for (const_iterator BB = begin(); BB != end(); ++BB) 299 BB->print(OS); 300 301 OS << "\n# End machine code for " << Fn->getName () << "().\n\n"; 302 } 303 304 /// CFGOnly flag - This is used to control whether or not the CFG graph printer 305 /// prints out the contents of basic blocks or not. This is acceptable because 306 /// this code is only really used for debugging purposes. 307 /// 308 static bool CFGOnly = false; 309 310 namespace llvm { 311 template<> 312 struct DOTGraphTraits<const MachineFunction*> : public DefaultDOTGraphTraits { 313 static std::string getGraphName(const MachineFunction *F) { 314 return "CFG for '" + F->getFunction()->getName() + "' function"; 315 } 316 317 static std::string getNodeLabel(const MachineBasicBlock *Node, 318 const MachineFunction *Graph) { 319 if (CFGOnly && Node->getBasicBlock() && 320 !Node->getBasicBlock()->getName().empty()) 321 return Node->getBasicBlock()->getName() + ":"; 322 323 std::ostringstream Out; 324 if (CFGOnly) { 325 Out << Node->getNumber() << ':'; 326 return Out.str(); 327 } 328 329 Node->print(Out); 330 331 std::string OutStr = Out.str(); 332 if (OutStr[0] == '\n') OutStr.erase(OutStr.begin()); 333 334 // Process string output to make it nicer... 335 for (unsigned i = 0; i != OutStr.length(); ++i) 336 if (OutStr[i] == '\n') { // Left justify 337 OutStr[i] = '\\'; 338 OutStr.insert(OutStr.begin()+i+1, 'l'); 339 } 340 return OutStr; 341 } 342 }; 343 } 344 345 void MachineFunction::viewCFG() const 346 { 347 #ifndef NDEBUG 348 ViewGraph(this, "mf" + getFunction()->getName()); 349 #else 350 cerr << "SelectionDAG::viewGraph is only available in debug builds on " 351 << "systems with Graphviz or gv!\n"; 352 #endif // NDEBUG 353 } 354 355 void MachineFunction::viewCFGOnly() const 356 { 357 CFGOnly = true; 358 viewCFG(); 359 CFGOnly = false; 360 } 361 362 // The next two methods are used to construct and to retrieve 363 // the MachineCodeForFunction object for the given function. 364 // construct() -- Allocates and initializes for a given function and target 365 // get() -- Returns a handle to the object. 366 // This should not be called before "construct()" 367 // for a given Function. 368 // 369 MachineFunction& 370 MachineFunction::construct(const Function *Fn, const TargetMachine &Tar) 371 { 372 assert(Fn->getAnnotation(MF_AID) == 0 && 373 "Object already exists for this function!"); 374 MachineFunction* mcInfo = new MachineFunction(Fn, Tar); 375 Fn->addAnnotation(mcInfo); 376 return *mcInfo; 377 } 378 379 void MachineFunction::destruct(const Function *Fn) { 380 bool Deleted = Fn->deleteAnnotation(MF_AID); 381 assert(Deleted && "Machine code did not exist for function!"); 382 Deleted = Deleted; // silence warning when no assertions. 383 } 384 385 MachineFunction& MachineFunction::get(const Function *F) 386 { 387 MachineFunction *mc = (MachineFunction*)F->getAnnotation(MF_AID); 388 assert(mc && "Call construct() method first to allocate the object"); 389 return *mc; 390 } 391 392 //===----------------------------------------------------------------------===// 393 // MachineFrameInfo implementation 394 //===----------------------------------------------------------------------===// 395 396 /// CreateFixedObject - Create a new object at a fixed location on the stack. 397 /// All fixed objects should be created before other objects are created for 398 /// efficiency. By default, fixed objects are immutable. This returns an 399 /// index with a negative value. 400 /// 401 int MachineFrameInfo::CreateFixedObject(uint64_t Size, int64_t SPOffset, 402 bool Immutable) { 403 assert(Size != 0 && "Cannot allocate zero size fixed stack objects!"); 404 Objects.insert(Objects.begin(), StackObject(Size, 1, SPOffset, Immutable)); 405 return -++NumFixedObjects; 406 } 407 408 409 void MachineFrameInfo::print(const MachineFunction &MF, std::ostream &OS) const{ 410 int ValOffset = MF.getTarget().getFrameInfo()->getOffsetOfLocalArea(); 411 412 for (unsigned i = 0, e = Objects.size(); i != e; ++i) { 413 const StackObject &SO = Objects[i]; 414 OS << " <fi #" << (int)(i-NumFixedObjects) << ">: "; 415 if (SO.Size == ~0ULL) { 416 OS << "dead\n"; 417 continue; 418 } 419 if (SO.Size == 0) 420 OS << "variable sized"; 421 else 422 OS << "size is " << SO.Size << " byte" << (SO.Size != 1 ? "s," : ","); 423 OS << " alignment is " << SO.Alignment << " byte" 424 << (SO.Alignment != 1 ? "s," : ","); 425 426 if (i < NumFixedObjects) 427 OS << " fixed"; 428 if (i < NumFixedObjects || SO.SPOffset != -1) { 429 int64_t Off = SO.SPOffset - ValOffset; 430 OS << " at location [SP"; 431 if (Off > 0) 432 OS << "+" << Off; 433 else if (Off < 0) 434 OS << Off; 435 OS << "]"; 436 } 437 OS << "\n"; 438 } 439 440 if (HasVarSizedObjects) 441 OS << " Stack frame contains variable sized objects\n"; 442 } 443 444 void MachineFrameInfo::dump(const MachineFunction &MF) const { 445 print(MF, *cerr.stream()); 446 } 447 448 449 //===----------------------------------------------------------------------===// 450 // MachineJumpTableInfo implementation 451 //===----------------------------------------------------------------------===// 452 453 /// getJumpTableIndex - Create a new jump table entry in the jump table info 454 /// or return an existing one. 455 /// 456 unsigned MachineJumpTableInfo::getJumpTableIndex( 457 const std::vector<MachineBasicBlock*> &DestBBs) { 458 assert(!DestBBs.empty() && "Cannot create an empty jump table!"); 459 for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) 460 if (JumpTables[i].MBBs == DestBBs) 461 return i; 462 463 JumpTables.push_back(MachineJumpTableEntry(DestBBs)); 464 return JumpTables.size()-1; 465 } 466 467 468 void MachineJumpTableInfo::print(std::ostream &OS) const { 469 // FIXME: this is lame, maybe we could print out the MBB numbers or something 470 // like {1, 2, 4, 5, 3, 0} 471 for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) { 472 OS << " <jt #" << i << "> has " << JumpTables[i].MBBs.size() 473 << " entries\n"; 474 } 475 } 476 477 void MachineJumpTableInfo::dump() const { print(*cerr.stream()); } 478 479 480 //===----------------------------------------------------------------------===// 481 // MachineConstantPool implementation 482 //===----------------------------------------------------------------------===// 483 484 const Type *MachineConstantPoolEntry::getType() const { 485 if (isMachineConstantPoolEntry()) 486 return Val.MachineCPVal->getType(); 487 return Val.ConstVal->getType(); 488 } 489 490 MachineConstantPool::~MachineConstantPool() { 491 for (unsigned i = 0, e = Constants.size(); i != e; ++i) 492 if (Constants[i].isMachineConstantPoolEntry()) 493 delete Constants[i].Val.MachineCPVal; 494 } 495 496 /// getConstantPoolIndex - Create a new entry in the constant pool or return 497 /// an existing one. User must specify an alignment in bytes for the object. 498 /// 499 unsigned MachineConstantPool::getConstantPoolIndex(Constant *C, 500 unsigned Alignment) { 501 assert(Alignment && "Alignment must be specified!"); 502 if (Alignment > PoolAlignment) PoolAlignment = Alignment; 503 504 // Check to see if we already have this constant. 505 // 506 // FIXME, this could be made much more efficient for large constant pools. 507 unsigned AlignMask = (1 << Alignment)-1; 508 for (unsigned i = 0, e = Constants.size(); i != e; ++i) 509 if (Constants[i].Val.ConstVal == C && (Constants[i].Offset & AlignMask)== 0) 510 return i; 511 512 unsigned Offset = 0; 513 if (!Constants.empty()) { 514 Offset = Constants.back().getOffset(); 515 Offset += TD->getABITypeSize(Constants.back().getType()); 516 Offset = (Offset+AlignMask)&~AlignMask; 517 } 518 519 Constants.push_back(MachineConstantPoolEntry(C, Offset)); 520 return Constants.size()-1; 521 } 522 523 unsigned MachineConstantPool::getConstantPoolIndex(MachineConstantPoolValue *V, 524 unsigned Alignment) { 525 assert(Alignment && "Alignment must be specified!"); 526 if (Alignment > PoolAlignment) PoolAlignment = Alignment; 527 528 // Check to see if we already have this constant. 529 // 530 // FIXME, this could be made much more efficient for large constant pools. 531 unsigned AlignMask = (1 << Alignment)-1; 532 int Idx = V->getExistingMachineCPValue(this, Alignment); 533 if (Idx != -1) 534 return (unsigned)Idx; 535 536 unsigned Offset = 0; 537 if (!Constants.empty()) { 538 Offset = Constants.back().getOffset(); 539 Offset += TD->getABITypeSize(Constants.back().getType()); 540 Offset = (Offset+AlignMask)&~AlignMask; 541 } 542 543 Constants.push_back(MachineConstantPoolEntry(V, Offset)); 544 return Constants.size()-1; 545 } 546 547 548 void MachineConstantPool::print(std::ostream &OS) const { 549 for (unsigned i = 0, e = Constants.size(); i != e; ++i) { 550 OS << " <cp #" << i << "> is"; 551 if (Constants[i].isMachineConstantPoolEntry()) 552 Constants[i].Val.MachineCPVal->print(OS); 553 else 554 OS << *(Value*)Constants[i].Val.ConstVal; 555 OS << " , offset=" << Constants[i].getOffset(); 556 OS << "\n"; 557 } 558 } 559 560 void MachineConstantPool::dump() const { print(*cerr.stream()); } 561