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/TargetMachine.h" 26 #include "llvm/Target/TargetFrameInfo.h" 27 #include "llvm/Function.h" 28 #include "llvm/Instructions.h" 29 #include "llvm/Support/Compiler.h" 30 #include "llvm/Support/GraphWriter.h" 31 #include "llvm/Support/raw_ostream.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(&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(&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 ilist_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 if (TM.getRegisterInfo()) 114 RegInfo = new (Allocator.Allocate<MachineRegisterInfo>()) 115 MachineRegisterInfo(*TM.getRegisterInfo()); 116 else 117 RegInfo = 0; 118 MFInfo = 0; 119 FrameInfo = new (Allocator.Allocate<MachineFrameInfo>()) 120 MachineFrameInfo(*TM.getFrameInfo()); 121 ConstantPool = new (Allocator.Allocate<MachineConstantPool>()) 122 MachineConstantPool(TM.getTargetData()); 123 124 // Set up jump table. 125 const TargetData &TD = *TM.getTargetData(); 126 bool IsPic = TM.getRelocationModel() == Reloc::PIC_; 127 unsigned EntrySize = IsPic ? 4 : TD.getPointerSize(); 128 unsigned Alignment = IsPic ? TD.getABITypeAlignment(Type::Int32Ty) 129 : TD.getPointerABIAlignment(); 130 JumpTableInfo = new (Allocator.Allocate<MachineJumpTableInfo>()) 131 MachineJumpTableInfo(EntrySize, Alignment); 132 } 133 134 MachineFunction::~MachineFunction() { 135 BasicBlocks.clear(); 136 InstructionRecycler.clear(Allocator); 137 BasicBlockRecycler.clear(Allocator); 138 if (RegInfo) 139 RegInfo->~MachineRegisterInfo(); Allocator.Deallocate(RegInfo); 140 if (MFInfo) { 141 MFInfo->~MachineFunctionInfo(); Allocator.Deallocate(MFInfo); 142 } 143 FrameInfo->~MachineFrameInfo(); Allocator.Deallocate(FrameInfo); 144 ConstantPool->~MachineConstantPool(); Allocator.Deallocate(ConstantPool); 145 JumpTableInfo->~MachineJumpTableInfo(); Allocator.Deallocate(JumpTableInfo); 146 } 147 148 149 /// RenumberBlocks - This discards all of the MachineBasicBlock numbers and 150 /// recomputes them. This guarantees that the MBB numbers are sequential, 151 /// dense, and match the ordering of the blocks within the function. If a 152 /// specific MachineBasicBlock is specified, only that block and those after 153 /// it are renumbered. 154 void MachineFunction::RenumberBlocks(MachineBasicBlock *MBB) { 155 if (empty()) { MBBNumbering.clear(); return; } 156 MachineFunction::iterator MBBI, E = end(); 157 if (MBB == 0) 158 MBBI = begin(); 159 else 160 MBBI = MBB; 161 162 // Figure out the block number this should have. 163 unsigned BlockNo = 0; 164 if (MBBI != begin()) 165 BlockNo = prior(MBBI)->getNumber()+1; 166 167 for (; MBBI != E; ++MBBI, ++BlockNo) { 168 if (MBBI->getNumber() != (int)BlockNo) { 169 // Remove use of the old number. 170 if (MBBI->getNumber() != -1) { 171 assert(MBBNumbering[MBBI->getNumber()] == &*MBBI && 172 "MBB number mismatch!"); 173 MBBNumbering[MBBI->getNumber()] = 0; 174 } 175 176 // If BlockNo is already taken, set that block's number to -1. 177 if (MBBNumbering[BlockNo]) 178 MBBNumbering[BlockNo]->setNumber(-1); 179 180 MBBNumbering[BlockNo] = MBBI; 181 MBBI->setNumber(BlockNo); 182 } 183 } 184 185 // Okay, all the blocks are renumbered. If we have compactified the block 186 // numbering, shrink MBBNumbering now. 187 assert(BlockNo <= MBBNumbering.size() && "Mismatch!"); 188 MBBNumbering.resize(BlockNo); 189 } 190 191 /// CreateMachineInstr - Allocate a new MachineInstr. Use this instead 192 /// of `new MachineInstr'. 193 /// 194 MachineInstr * 195 MachineFunction::CreateMachineInstr(const TargetInstrDesc &TID, bool NoImp) { 196 return new (InstructionRecycler.Allocate<MachineInstr>(Allocator)) 197 MachineInstr(TID, NoImp); 198 } 199 200 /// CloneMachineInstr - Create a new MachineInstr which is a copy of the 201 /// 'Orig' instruction, identical in all ways except the the instruction 202 /// has no parent, prev, or next. 203 /// 204 MachineInstr * 205 MachineFunction::CloneMachineInstr(const MachineInstr *Orig) { 206 return new (InstructionRecycler.Allocate<MachineInstr>(Allocator)) 207 MachineInstr(*this, *Orig); 208 } 209 210 /// DeleteMachineInstr - Delete the given MachineInstr. 211 /// 212 void 213 MachineFunction::DeleteMachineInstr(MachineInstr *MI) { 214 // Clear the instructions memoperands. This must be done manually because 215 // the instruction's parent pointer is now null, so it can't properly 216 // deallocate them on its own. 217 MI->clearMemOperands(*this); 218 219 MI->~MachineInstr(); 220 InstructionRecycler.Deallocate(Allocator, MI); 221 } 222 223 /// CreateMachineBasicBlock - Allocate a new MachineBasicBlock. Use this 224 /// instead of `new MachineBasicBlock'. 225 /// 226 MachineBasicBlock * 227 MachineFunction::CreateMachineBasicBlock(const BasicBlock *bb) { 228 return new (BasicBlockRecycler.Allocate<MachineBasicBlock>(Allocator)) 229 MachineBasicBlock(*this, bb); 230 } 231 232 /// DeleteMachineBasicBlock - Delete the given MachineBasicBlock. 233 /// 234 void 235 MachineFunction::DeleteMachineBasicBlock(MachineBasicBlock *MBB) { 236 assert(MBB->getParent() == this && "MBB parent mismatch!"); 237 MBB->~MachineBasicBlock(); 238 BasicBlockRecycler.Deallocate(Allocator, MBB); 239 } 240 241 void MachineFunction::dump() const { 242 print(*cerr.stream()); 243 } 244 245 void MachineFunction::print(std::ostream &OS) const { 246 OS << "# Machine code for " << Fn->getName () << "():\n"; 247 248 // Print Frame Information 249 FrameInfo->print(*this, OS); 250 251 // Print JumpTable Information 252 JumpTableInfo->print(OS); 253 254 // Print Constant Pool 255 { 256 raw_os_ostream OSS(OS); 257 ConstantPool->print(OSS); 258 } 259 260 const TargetRegisterInfo *TRI = getTarget().getRegisterInfo(); 261 262 if (RegInfo && !RegInfo->livein_empty()) { 263 OS << "Live Ins:"; 264 for (MachineRegisterInfo::livein_iterator 265 I = RegInfo->livein_begin(), E = RegInfo->livein_end(); I != E; ++I) { 266 if (TRI) 267 OS << " " << TRI->getName(I->first); 268 else 269 OS << " Reg #" << I->first; 270 271 if (I->second) 272 OS << " in VR#" << I->second << " "; 273 } 274 OS << "\n"; 275 } 276 if (RegInfo && !RegInfo->liveout_empty()) { 277 OS << "Live Outs:"; 278 for (MachineRegisterInfo::liveout_iterator 279 I = RegInfo->liveout_begin(), E = RegInfo->liveout_end(); I != E; ++I) 280 if (TRI) 281 OS << " " << TRI->getName(*I); 282 else 283 OS << " Reg #" << *I; 284 OS << "\n"; 285 } 286 287 for (const_iterator BB = begin(); BB != end(); ++BB) 288 BB->print(OS); 289 290 OS << "\n# End machine code for " << Fn->getName () << "().\n\n"; 291 } 292 293 /// CFGOnly flag - This is used to control whether or not the CFG graph printer 294 /// prints out the contents of basic blocks or not. This is acceptable because 295 /// this code is only really used for debugging purposes. 296 /// 297 static bool CFGOnly = false; 298 299 namespace llvm { 300 template<> 301 struct DOTGraphTraits<const MachineFunction*> : public DefaultDOTGraphTraits { 302 static std::string getGraphName(const MachineFunction *F) { 303 return "CFG for '" + F->getFunction()->getName() + "' function"; 304 } 305 306 static std::string getNodeLabel(const MachineBasicBlock *Node, 307 const MachineFunction *Graph) { 308 if (CFGOnly && Node->getBasicBlock() && 309 !Node->getBasicBlock()->getName().empty()) 310 return Node->getBasicBlock()->getName() + ":"; 311 312 std::ostringstream Out; 313 if (CFGOnly) { 314 Out << Node->getNumber() << ':'; 315 return Out.str(); 316 } 317 318 Node->print(Out); 319 320 std::string OutStr = Out.str(); 321 if (OutStr[0] == '\n') OutStr.erase(OutStr.begin()); 322 323 // Process string output to make it nicer... 324 for (unsigned i = 0; i != OutStr.length(); ++i) 325 if (OutStr[i] == '\n') { // Left justify 326 OutStr[i] = '\\'; 327 OutStr.insert(OutStr.begin()+i+1, 'l'); 328 } 329 return OutStr; 330 } 331 }; 332 } 333 334 void MachineFunction::viewCFG() const 335 { 336 #ifndef NDEBUG 337 ViewGraph(this, "mf" + getFunction()->getName()); 338 #else 339 cerr << "SelectionDAG::viewGraph is only available in debug builds on " 340 << "systems with Graphviz or gv!\n"; 341 #endif // NDEBUG 342 } 343 344 void MachineFunction::viewCFGOnly() const 345 { 346 CFGOnly = true; 347 viewCFG(); 348 CFGOnly = false; 349 } 350 351 // The next two methods are used to construct and to retrieve 352 // the MachineCodeForFunction object for the given function. 353 // construct() -- Allocates and initializes for a given function and target 354 // get() -- Returns a handle to the object. 355 // This should not be called before "construct()" 356 // for a given Function. 357 // 358 MachineFunction& 359 MachineFunction::construct(const Function *Fn, const TargetMachine &Tar) 360 { 361 assert(Fn->getAnnotation(MF_AID) == 0 && 362 "Object already exists for this function!"); 363 MachineFunction* mcInfo = new MachineFunction(Fn, Tar); 364 Fn->addAnnotation(mcInfo); 365 return *mcInfo; 366 } 367 368 void MachineFunction::destruct(const Function *Fn) { 369 bool Deleted = Fn->deleteAnnotation(MF_AID); 370 assert(Deleted && "Machine code did not exist for function!"); 371 Deleted = Deleted; // silence warning when no assertions. 372 } 373 374 MachineFunction& MachineFunction::get(const Function *F) 375 { 376 MachineFunction *mc = (MachineFunction*)F->getAnnotation(MF_AID); 377 assert(mc && "Call construct() method first to allocate the object"); 378 return *mc; 379 } 380 381 /// lookUpDebugLocId - Look up the DebugLocTuple index with the given 382 /// filename, line, and column. It may add a new filename and / or 383 /// a new DebugLocTuple. 384 unsigned MachineFunction::lookUpDebugLocId(const char *Filename, unsigned Line, 385 unsigned Col) { 386 unsigned FileId; 387 StringMap<unsigned>::iterator I = 388 DebugLocInfo.DebugFilenamesMap.find(Filename); 389 if (I != DebugLocInfo.DebugFilenamesMap.end()) 390 FileId = I->second; 391 else { 392 // Add a new filename. 393 FileId = DebugLocInfo.NumFilenames++; 394 DebugLocInfo.DebugFilenames.push_back(Filename); 395 DebugLocInfo.DebugFilenamesMap[Filename] = FileId; 396 } 397 398 struct DebugLocTuple Tuple(FileId, Line, Col); 399 DebugIdMapType::iterator II = DebugLocInfo.DebugIdMap.find(Tuple); 400 if (II != DebugLocInfo.DebugIdMap.end()) 401 return II->second; 402 // Add a new tuple. 403 DebugLocInfo.DebugLocations.push_back(Tuple); 404 DebugLocInfo.DebugIdMap[Tuple] = DebugLocInfo.NumDebugLocations; 405 return DebugLocInfo.NumDebugLocations++; 406 } 407 408 //===----------------------------------------------------------------------===// 409 // MachineFrameInfo implementation 410 //===----------------------------------------------------------------------===// 411 412 /// CreateFixedObject - Create a new object at a fixed location on the stack. 413 /// All fixed objects should be created before other objects are created for 414 /// efficiency. By default, fixed objects are immutable. This returns an 415 /// index with a negative value. 416 /// 417 int MachineFrameInfo::CreateFixedObject(uint64_t Size, int64_t SPOffset, 418 bool Immutable) { 419 assert(Size != 0 && "Cannot allocate zero size fixed stack objects!"); 420 Objects.insert(Objects.begin(), StackObject(Size, 1, SPOffset, Immutable)); 421 return -++NumFixedObjects; 422 } 423 424 425 void MachineFrameInfo::print(const MachineFunction &MF, std::ostream &OS) const{ 426 const TargetFrameInfo *FI = MF.getTarget().getFrameInfo(); 427 int ValOffset = (FI ? FI->getOffsetOfLocalArea() : 0); 428 429 for (unsigned i = 0, e = Objects.size(); i != e; ++i) { 430 const StackObject &SO = Objects[i]; 431 OS << " <fi#" << (int)(i-NumFixedObjects) << ">: "; 432 if (SO.Size == ~0ULL) { 433 OS << "dead\n"; 434 continue; 435 } 436 if (SO.Size == 0) 437 OS << "variable sized"; 438 else 439 OS << "size is " << SO.Size << " byte" << (SO.Size != 1 ? "s," : ","); 440 OS << " alignment is " << SO.Alignment << " byte" 441 << (SO.Alignment != 1 ? "s," : ","); 442 443 if (i < NumFixedObjects) 444 OS << " fixed"; 445 if (i < NumFixedObjects || SO.SPOffset != -1) { 446 int64_t Off = SO.SPOffset - ValOffset; 447 OS << " at location [SP"; 448 if (Off > 0) 449 OS << "+" << Off; 450 else if (Off < 0) 451 OS << Off; 452 OS << "]"; 453 } 454 OS << "\n"; 455 } 456 457 if (HasVarSizedObjects) 458 OS << " Stack frame contains variable sized objects\n"; 459 } 460 461 void MachineFrameInfo::dump(const MachineFunction &MF) const { 462 print(MF, *cerr.stream()); 463 } 464 465 466 //===----------------------------------------------------------------------===// 467 // MachineJumpTableInfo implementation 468 //===----------------------------------------------------------------------===// 469 470 /// getJumpTableIndex - Create a new jump table entry in the jump table info 471 /// or return an existing one. 472 /// 473 unsigned MachineJumpTableInfo::getJumpTableIndex( 474 const std::vector<MachineBasicBlock*> &DestBBs) { 475 assert(!DestBBs.empty() && "Cannot create an empty jump table!"); 476 for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) 477 if (JumpTables[i].MBBs == DestBBs) 478 return i; 479 480 JumpTables.push_back(MachineJumpTableEntry(DestBBs)); 481 return JumpTables.size()-1; 482 } 483 484 485 void MachineJumpTableInfo::print(std::ostream &OS) const { 486 // FIXME: this is lame, maybe we could print out the MBB numbers or something 487 // like {1, 2, 4, 5, 3, 0} 488 for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) { 489 OS << " <jt#" << i << "> has " << JumpTables[i].MBBs.size() 490 << " entries\n"; 491 } 492 } 493 494 void MachineJumpTableInfo::dump() const { print(*cerr.stream()); } 495 496 497 //===----------------------------------------------------------------------===// 498 // MachineConstantPool implementation 499 //===----------------------------------------------------------------------===// 500 501 const Type *MachineConstantPoolEntry::getType() const { 502 if (isMachineConstantPoolEntry()) 503 return Val.MachineCPVal->getType(); 504 return Val.ConstVal->getType(); 505 } 506 507 MachineConstantPool::~MachineConstantPool() { 508 for (unsigned i = 0, e = Constants.size(); i != e; ++i) 509 if (Constants[i].isMachineConstantPoolEntry()) 510 delete Constants[i].Val.MachineCPVal; 511 } 512 513 /// getConstantPoolIndex - Create a new entry in the constant pool or return 514 /// an existing one. User must specify the log2 of the minimum required 515 /// alignment for the object. 516 /// 517 unsigned MachineConstantPool::getConstantPoolIndex(Constant *C, 518 unsigned Alignment) { 519 assert(Alignment && "Alignment must be specified!"); 520 if (Alignment > PoolAlignment) PoolAlignment = Alignment; 521 522 // Check to see if we already have this constant. 523 // 524 // FIXME, this could be made much more efficient for large constant pools. 525 unsigned AlignMask = (1 << Alignment)-1; 526 for (unsigned i = 0, e = Constants.size(); i != e; ++i) 527 if (Constants[i].Val.ConstVal == C && (Constants[i].Offset & AlignMask)== 0) 528 return i; 529 530 unsigned Offset = 0; 531 if (!Constants.empty()) { 532 Offset = Constants.back().getOffset(); 533 Offset += TD->getTypePaddedSize(Constants.back().getType()); 534 Offset = (Offset+AlignMask)&~AlignMask; 535 } 536 537 Constants.push_back(MachineConstantPoolEntry(C, Offset)); 538 return Constants.size()-1; 539 } 540 541 unsigned MachineConstantPool::getConstantPoolIndex(MachineConstantPoolValue *V, 542 unsigned Alignment) { 543 assert(Alignment && "Alignment must be specified!"); 544 if (Alignment > PoolAlignment) PoolAlignment = Alignment; 545 546 // Check to see if we already have this constant. 547 // 548 // FIXME, this could be made much more efficient for large constant pools. 549 unsigned AlignMask = (1 << Alignment)-1; 550 int Idx = V->getExistingMachineCPValue(this, Alignment); 551 if (Idx != -1) 552 return (unsigned)Idx; 553 554 unsigned Offset = 0; 555 if (!Constants.empty()) { 556 Offset = Constants.back().getOffset(); 557 Offset += TD->getTypePaddedSize(Constants.back().getType()); 558 Offset = (Offset+AlignMask)&~AlignMask; 559 } 560 561 Constants.push_back(MachineConstantPoolEntry(V, Offset)); 562 return Constants.size()-1; 563 } 564 565 void MachineConstantPool::print(raw_ostream &OS) const { 566 for (unsigned i = 0, e = Constants.size(); i != e; ++i) { 567 OS << " <cp#" << i << "> is"; 568 if (Constants[i].isMachineConstantPoolEntry()) 569 Constants[i].Val.MachineCPVal->print(OS); 570 else 571 OS << *(Value*)Constants[i].Val.ConstVal; 572 OS << " , offset=" << Constants[i].getOffset(); 573 OS << "\n"; 574 } 575 } 576 577 void MachineConstantPool::dump() const { print(errs()); errs().flush(); } 578