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/Function.h" 18 #include "llvm/Instructions.h" 19 #include "llvm/ADT/STLExtras.h" 20 #include "llvm/Config/config.h" 21 #include "llvm/CodeGen/MachineConstantPool.h" 22 #include "llvm/CodeGen/MachineFunction.h" 23 #include "llvm/CodeGen/MachineFunctionPass.h" 24 #include "llvm/CodeGen/MachineFrameInfo.h" 25 #include "llvm/CodeGen/MachineInstr.h" 26 #include "llvm/CodeGen/MachineJumpTableInfo.h" 27 #include "llvm/CodeGen/MachineRegisterInfo.h" 28 #include "llvm/CodeGen/Passes.h" 29 #include "llvm/Target/TargetData.h" 30 #include "llvm/Target/TargetLowering.h" 31 #include "llvm/Target/TargetMachine.h" 32 #include "llvm/Target/TargetFrameInfo.h" 33 #include "llvm/Support/Compiler.h" 34 #include "llvm/Support/GraphWriter.h" 35 #include "llvm/Support/raw_ostream.h" 36 using namespace llvm; 37 38 namespace { 39 struct VISIBILITY_HIDDEN Printer : public MachineFunctionPass { 40 static char ID; 41 42 raw_ostream &OS; 43 const std::string Banner; 44 45 Printer(raw_ostream &os, const std::string &banner) 46 : MachineFunctionPass(&ID), OS(os), Banner(banner) {} 47 48 const char *getPassName() const { return "MachineFunction Printer"; } 49 50 virtual void getAnalysisUsage(AnalysisUsage &AU) const { 51 AU.setPreservesAll(); 52 MachineFunctionPass::getAnalysisUsage(AU); 53 } 54 55 bool runOnMachineFunction(MachineFunction &MF) { 56 OS << Banner; 57 MF.print(OS); 58 return false; 59 } 60 }; 61 char Printer::ID = 0; 62 } 63 64 /// Returns a newly-created MachineFunction Printer pass. The default banner is 65 /// empty. 66 /// 67 FunctionPass *llvm::createMachineFunctionPrinterPass(raw_ostream &OS, 68 const std::string &Banner){ 69 return new Printer(OS, Banner); 70 } 71 72 //===---------------------------------------------------------------------===// 73 // MachineFunction implementation 74 //===---------------------------------------------------------------------===// 75 76 // Out of line virtual method. 77 MachineFunctionInfo::~MachineFunctionInfo() {} 78 79 void ilist_traits<MachineBasicBlock>::deleteNode(MachineBasicBlock *MBB) { 80 MBB->getParent()->DeleteMachineBasicBlock(MBB); 81 } 82 83 MachineFunction::MachineFunction(Function *F, 84 const TargetMachine &TM) 85 : Fn(F), Target(TM) { 86 if (TM.getRegisterInfo()) 87 RegInfo = new (Allocator.Allocate<MachineRegisterInfo>()) 88 MachineRegisterInfo(*TM.getRegisterInfo()); 89 else 90 RegInfo = 0; 91 MFInfo = 0; 92 FrameInfo = new (Allocator.Allocate<MachineFrameInfo>()) 93 MachineFrameInfo(*TM.getFrameInfo()); 94 ConstantPool = new (Allocator.Allocate<MachineConstantPool>()) 95 MachineConstantPool(TM.getTargetData()); 96 Alignment = TM.getTargetLowering()->getFunctionAlignment(F); 97 98 // Set up jump table. 99 const TargetData &TD = *TM.getTargetData(); 100 bool IsPic = TM.getRelocationModel() == Reloc::PIC_; 101 unsigned EntrySize = IsPic ? 4 : TD.getPointerSize(); 102 unsigned TyAlignment = IsPic ? 103 TD.getABITypeAlignment(Type::getInt32Ty(F->getContext())) 104 : TD.getPointerABIAlignment(); 105 JumpTableInfo = new (Allocator.Allocate<MachineJumpTableInfo>()) 106 MachineJumpTableInfo(EntrySize, TyAlignment); 107 } 108 109 MachineFunction::~MachineFunction() { 110 BasicBlocks.clear(); 111 InstructionRecycler.clear(Allocator); 112 BasicBlockRecycler.clear(Allocator); 113 if (RegInfo) { 114 RegInfo->~MachineRegisterInfo(); 115 Allocator.Deallocate(RegInfo); 116 } 117 if (MFInfo) { 118 MFInfo->~MachineFunctionInfo(); 119 Allocator.Deallocate(MFInfo); 120 } 121 FrameInfo->~MachineFrameInfo(); Allocator.Deallocate(FrameInfo); 122 ConstantPool->~MachineConstantPool(); Allocator.Deallocate(ConstantPool); 123 JumpTableInfo->~MachineJumpTableInfo(); Allocator.Deallocate(JumpTableInfo); 124 } 125 126 127 /// RenumberBlocks - This discards all of the MachineBasicBlock numbers and 128 /// recomputes them. This guarantees that the MBB numbers are sequential, 129 /// dense, and match the ordering of the blocks within the function. If a 130 /// specific MachineBasicBlock is specified, only that block and those after 131 /// it are renumbered. 132 void MachineFunction::RenumberBlocks(MachineBasicBlock *MBB) { 133 if (empty()) { MBBNumbering.clear(); return; } 134 MachineFunction::iterator MBBI, E = end(); 135 if (MBB == 0) 136 MBBI = begin(); 137 else 138 MBBI = MBB; 139 140 // Figure out the block number this should have. 141 unsigned BlockNo = 0; 142 if (MBBI != begin()) 143 BlockNo = prior(MBBI)->getNumber()+1; 144 145 for (; MBBI != E; ++MBBI, ++BlockNo) { 146 if (MBBI->getNumber() != (int)BlockNo) { 147 // Remove use of the old number. 148 if (MBBI->getNumber() != -1) { 149 assert(MBBNumbering[MBBI->getNumber()] == &*MBBI && 150 "MBB number mismatch!"); 151 MBBNumbering[MBBI->getNumber()] = 0; 152 } 153 154 // If BlockNo is already taken, set that block's number to -1. 155 if (MBBNumbering[BlockNo]) 156 MBBNumbering[BlockNo]->setNumber(-1); 157 158 MBBNumbering[BlockNo] = MBBI; 159 MBBI->setNumber(BlockNo); 160 } 161 } 162 163 // Okay, all the blocks are renumbered. If we have compactified the block 164 // numbering, shrink MBBNumbering now. 165 assert(BlockNo <= MBBNumbering.size() && "Mismatch!"); 166 MBBNumbering.resize(BlockNo); 167 } 168 169 /// CreateMachineInstr - Allocate a new MachineInstr. Use this instead 170 /// of `new MachineInstr'. 171 /// 172 MachineInstr * 173 MachineFunction::CreateMachineInstr(const TargetInstrDesc &TID, 174 DebugLoc DL, bool NoImp) { 175 return new (InstructionRecycler.Allocate<MachineInstr>(Allocator)) 176 MachineInstr(TID, DL, NoImp); 177 } 178 179 /// CloneMachineInstr - Create a new MachineInstr which is a copy of the 180 /// 'Orig' instruction, identical in all ways except the the instruction 181 /// has no parent, prev, or next. 182 /// 183 MachineInstr * 184 MachineFunction::CloneMachineInstr(const MachineInstr *Orig) { 185 return new (InstructionRecycler.Allocate<MachineInstr>(Allocator)) 186 MachineInstr(*this, *Orig); 187 } 188 189 /// DeleteMachineInstr - Delete the given MachineInstr. 190 /// 191 void 192 MachineFunction::DeleteMachineInstr(MachineInstr *MI) { 193 MI->~MachineInstr(); 194 InstructionRecycler.Deallocate(Allocator, MI); 195 } 196 197 /// CreateMachineBasicBlock - Allocate a new MachineBasicBlock. Use this 198 /// instead of `new MachineBasicBlock'. 199 /// 200 MachineBasicBlock * 201 MachineFunction::CreateMachineBasicBlock(const BasicBlock *bb) { 202 return new (BasicBlockRecycler.Allocate<MachineBasicBlock>(Allocator)) 203 MachineBasicBlock(*this, bb); 204 } 205 206 /// DeleteMachineBasicBlock - Delete the given MachineBasicBlock. 207 /// 208 void 209 MachineFunction::DeleteMachineBasicBlock(MachineBasicBlock *MBB) { 210 assert(MBB->getParent() == this && "MBB parent mismatch!"); 211 MBB->~MachineBasicBlock(); 212 BasicBlockRecycler.Deallocate(Allocator, MBB); 213 } 214 215 MachineMemOperand * 216 MachineFunction::getMachineMemOperand(const Value *v, unsigned f, 217 int64_t o, uint64_t s, 218 unsigned base_alignment) { 219 return new (Allocator.Allocate<MachineMemOperand>()) 220 MachineMemOperand(v, f, o, s, base_alignment); 221 } 222 223 MachineMemOperand * 224 MachineFunction::getMachineMemOperand(const MachineMemOperand *MMO, 225 int64_t Offset, uint64_t Size) { 226 return new (Allocator.Allocate<MachineMemOperand>()) 227 MachineMemOperand(MMO->getValue(), MMO->getFlags(), 228 int64_t(uint64_t(MMO->getOffset()) + 229 uint64_t(Offset)), 230 Size, MMO->getBaseAlignment()); 231 } 232 233 MachineInstr::mmo_iterator 234 MachineFunction::allocateMemRefsArray(unsigned long Num) { 235 return Allocator.Allocate<MachineMemOperand *>(Num); 236 } 237 238 void MachineFunction::dump() const { 239 print(errs()); 240 } 241 242 void MachineFunction::print(raw_ostream &OS) const { 243 OS << "# Machine code for " << Fn->getName() << "():\n"; 244 245 // Print Frame Information 246 FrameInfo->print(*this, OS); 247 248 // Print JumpTable Information 249 JumpTableInfo->print(OS); 250 251 // Print Constant Pool 252 ConstantPool->print(OS); 253 254 const TargetRegisterInfo *TRI = getTarget().getRegisterInfo(); 255 256 if (RegInfo && !RegInfo->livein_empty()) { 257 OS << "Live Ins:"; 258 for (MachineRegisterInfo::livein_iterator 259 I = RegInfo->livein_begin(), E = RegInfo->livein_end(); I != E; ++I) { 260 if (TRI) 261 OS << " " << TRI->getName(I->first); 262 else 263 OS << " Reg #" << I->first; 264 265 if (I->second) 266 OS << " in VR#" << I->second << ' '; 267 } 268 OS << '\n'; 269 } 270 if (RegInfo && !RegInfo->liveout_empty()) { 271 OS << "Live Outs:"; 272 for (MachineRegisterInfo::liveout_iterator 273 I = RegInfo->liveout_begin(), E = RegInfo->liveout_end(); I != E; ++I) 274 if (TRI) 275 OS << ' ' << TRI->getName(*I); 276 else 277 OS << " Reg #" << *I; 278 OS << '\n'; 279 } 280 281 for (const_iterator BB = begin(), E = end(); BB != E; ++BB) 282 BB->print(OS); 283 284 OS << "\n# End machine code for " << Fn->getName() << "().\n\n"; 285 } 286 287 namespace llvm { 288 template<> 289 struct DOTGraphTraits<const MachineFunction*> : public DefaultDOTGraphTraits { 290 static std::string getGraphName(const MachineFunction *F) { 291 return "CFG for '" + F->getFunction()->getNameStr() + "' function"; 292 } 293 294 static std::string getNodeLabel(const MachineBasicBlock *Node, 295 const MachineFunction *Graph, 296 bool ShortNames) { 297 if (ShortNames && Node->getBasicBlock() && 298 !Node->getBasicBlock()->getName().empty()) 299 return Node->getBasicBlock()->getNameStr() + ":"; 300 301 std::string OutStr; 302 { 303 raw_string_ostream OSS(OutStr); 304 305 if (ShortNames) 306 OSS << Node->getNumber() << ':'; 307 else 308 Node->print(OSS); 309 } 310 311 if (OutStr[0] == '\n') OutStr.erase(OutStr.begin()); 312 313 // Process string output to make it nicer... 314 for (unsigned i = 0; i != OutStr.length(); ++i) 315 if (OutStr[i] == '\n') { // Left justify 316 OutStr[i] = '\\'; 317 OutStr.insert(OutStr.begin()+i+1, 'l'); 318 } 319 return OutStr; 320 } 321 }; 322 } 323 324 void MachineFunction::viewCFG() const 325 { 326 #ifndef NDEBUG 327 ViewGraph(this, "mf" + getFunction()->getNameStr()); 328 #else 329 errs() << "SelectionDAG::viewGraph is only available in debug builds on " 330 << "systems with Graphviz or gv!\n"; 331 #endif // NDEBUG 332 } 333 334 void MachineFunction::viewCFGOnly() const 335 { 336 #ifndef NDEBUG 337 ViewGraph(this, "mf" + getFunction()->getNameStr(), true); 338 #else 339 errs() << "SelectionDAG::viewGraph is only available in debug builds on " 340 << "systems with Graphviz or gv!\n"; 341 #endif // NDEBUG 342 } 343 344 /// addLiveIn - Add the specified physical register as a live-in value and 345 /// create a corresponding virtual register for it. 346 unsigned MachineFunction::addLiveIn(unsigned PReg, 347 const TargetRegisterClass *RC) { 348 assert(RC->contains(PReg) && "Not the correct regclass!"); 349 unsigned VReg = getRegInfo().createVirtualRegister(RC); 350 getRegInfo().addLiveIn(PReg, VReg); 351 return VReg; 352 } 353 354 /// getDebugLocTuple - Get the DebugLocTuple for a given DebugLoc object. 355 DebugLocTuple MachineFunction::getDebugLocTuple(DebugLoc DL) const { 356 unsigned Idx = DL.getIndex(); 357 assert(Idx < DebugLocInfo.DebugLocations.size() && 358 "Invalid index into debug locations!"); 359 return DebugLocInfo.DebugLocations[Idx]; 360 } 361 362 //===----------------------------------------------------------------------===// 363 // MachineFrameInfo implementation 364 //===----------------------------------------------------------------------===// 365 366 /// CreateFixedObject - Create a new object at a fixed location on the stack. 367 /// All fixed objects should be created before other objects are created for 368 /// efficiency. By default, fixed objects are immutable. This returns an 369 /// index with a negative value. 370 /// 371 int MachineFrameInfo::CreateFixedObject(uint64_t Size, int64_t SPOffset, 372 bool Immutable) { 373 assert(Size != 0 && "Cannot allocate zero size fixed stack objects!"); 374 Objects.insert(Objects.begin(), StackObject(Size, 1, SPOffset, Immutable)); 375 return -++NumFixedObjects; 376 } 377 378 379 BitVector 380 MachineFrameInfo::getPristineRegs(const MachineBasicBlock *MBB) const { 381 assert(MBB && "MBB must be valid"); 382 const MachineFunction *MF = MBB->getParent(); 383 assert(MF && "MBB must be part of a MachineFunction"); 384 const TargetMachine &TM = MF->getTarget(); 385 const TargetRegisterInfo *TRI = TM.getRegisterInfo(); 386 BitVector BV(TRI->getNumRegs()); 387 388 // Before CSI is calculated, no registers are considered pristine. They can be 389 // freely used and PEI will make sure they are saved. 390 if (!isCalleeSavedInfoValid()) 391 return BV; 392 393 for (const unsigned *CSR = TRI->getCalleeSavedRegs(MF); CSR && *CSR; ++CSR) 394 BV.set(*CSR); 395 396 // The entry MBB always has all CSRs pristine. 397 if (MBB == &MF->front()) 398 return BV; 399 400 // On other MBBs the saved CSRs are not pristine. 401 const std::vector<CalleeSavedInfo> &CSI = getCalleeSavedInfo(); 402 for (std::vector<CalleeSavedInfo>::const_iterator I = CSI.begin(), 403 E = CSI.end(); I != E; ++I) 404 BV.reset(I->getReg()); 405 406 return BV; 407 } 408 409 410 void MachineFrameInfo::print(const MachineFunction &MF, raw_ostream &OS) const{ 411 const TargetFrameInfo *FI = MF.getTarget().getFrameInfo(); 412 int ValOffset = (FI ? FI->getOffsetOfLocalArea() : 0); 413 414 for (unsigned i = 0, e = Objects.size(); i != e; ++i) { 415 const StackObject &SO = Objects[i]; 416 OS << " <fi#" << (int)(i-NumFixedObjects) << ">: "; 417 if (SO.Size == ~0ULL) { 418 OS << "dead\n"; 419 continue; 420 } 421 if (SO.Size == 0) 422 OS << "variable sized"; 423 else 424 OS << "size is " << SO.Size << " byte" << (SO.Size != 1 ? "s," : ","); 425 OS << " alignment is " << SO.Alignment << " byte" 426 << (SO.Alignment != 1 ? "s," : ","); 427 428 if (i < NumFixedObjects) 429 OS << " fixed"; 430 if (i < NumFixedObjects || SO.SPOffset != -1) { 431 int64_t Off = SO.SPOffset - ValOffset; 432 OS << " at location [SP"; 433 if (Off > 0) 434 OS << "+" << Off; 435 else if (Off < 0) 436 OS << Off; 437 OS << "]"; 438 } 439 OS << "\n"; 440 } 441 442 if (HasVarSizedObjects) 443 OS << " Stack frame contains variable sized objects\n"; 444 } 445 446 void MachineFrameInfo::dump(const MachineFunction &MF) const { 447 print(MF, errs()); 448 } 449 450 //===----------------------------------------------------------------------===// 451 // MachineJumpTableInfo implementation 452 //===----------------------------------------------------------------------===// 453 454 /// getJumpTableIndex - Create a new jump table entry in the jump table info 455 /// or return an existing one. 456 /// 457 unsigned MachineJumpTableInfo::getJumpTableIndex( 458 const std::vector<MachineBasicBlock*> &DestBBs) { 459 assert(!DestBBs.empty() && "Cannot create an empty jump table!"); 460 for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) 461 if (JumpTables[i].MBBs == DestBBs) 462 return i; 463 464 JumpTables.push_back(MachineJumpTableEntry(DestBBs)); 465 return JumpTables.size()-1; 466 } 467 468 /// ReplaceMBBInJumpTables - If Old is the target of any jump tables, update 469 /// the jump tables to branch to New instead. 470 bool 471 MachineJumpTableInfo::ReplaceMBBInJumpTables(MachineBasicBlock *Old, 472 MachineBasicBlock *New) { 473 assert(Old != New && "Not making a change?"); 474 bool MadeChange = false; 475 for (size_t i = 0, e = JumpTables.size(); i != e; ++i) { 476 MachineJumpTableEntry &JTE = JumpTables[i]; 477 for (size_t j = 0, e = JTE.MBBs.size(); j != e; ++j) 478 if (JTE.MBBs[j] == Old) { 479 JTE.MBBs[j] = New; 480 MadeChange = true; 481 } 482 } 483 return MadeChange; 484 } 485 486 void MachineJumpTableInfo::print(raw_ostream &OS) const { 487 // FIXME: this is lame, maybe we could print out the MBB numbers or something 488 // like {1, 2, 4, 5, 3, 0} 489 for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) { 490 OS << " <jt#" << i << "> has " << JumpTables[i].MBBs.size() 491 << " entries\n"; 492 } 493 } 494 495 void MachineJumpTableInfo::dump() const { print(errs()); } 496 497 498 //===----------------------------------------------------------------------===// 499 // MachineConstantPool implementation 500 //===----------------------------------------------------------------------===// 501 502 const Type *MachineConstantPoolEntry::getType() const { 503 if (isMachineConstantPoolEntry()) 504 return Val.MachineCPVal->getType(); 505 return Val.ConstVal->getType(); 506 } 507 508 509 unsigned MachineConstantPoolEntry::getRelocationInfo() const { 510 if (isMachineConstantPoolEntry()) 511 return Val.MachineCPVal->getRelocationInfo(); 512 return Val.ConstVal->getRelocationInfo(); 513 } 514 515 MachineConstantPool::~MachineConstantPool() { 516 for (unsigned i = 0, e = Constants.size(); i != e; ++i) 517 if (Constants[i].isMachineConstantPoolEntry()) 518 delete Constants[i].Val.MachineCPVal; 519 } 520 521 /// getConstantPoolIndex - Create a new entry in the constant pool or return 522 /// an existing one. User must specify the log2 of the minimum required 523 /// alignment for the object. 524 /// 525 unsigned MachineConstantPool::getConstantPoolIndex(Constant *C, 526 unsigned Alignment) { 527 assert(Alignment && "Alignment must be specified!"); 528 if (Alignment > PoolAlignment) PoolAlignment = Alignment; 529 530 // Check to see if we already have this constant. 531 // 532 // FIXME, this could be made much more efficient for large constant pools. 533 for (unsigned i = 0, e = Constants.size(); i != e; ++i) 534 if (Constants[i].Val.ConstVal == C && 535 (Constants[i].getAlignment() & (Alignment - 1)) == 0) 536 return i; 537 538 Constants.push_back(MachineConstantPoolEntry(C, Alignment)); 539 return Constants.size()-1; 540 } 541 542 unsigned MachineConstantPool::getConstantPoolIndex(MachineConstantPoolValue *V, 543 unsigned Alignment) { 544 assert(Alignment && "Alignment must be specified!"); 545 if (Alignment > PoolAlignment) PoolAlignment = Alignment; 546 547 // Check to see if we already have this constant. 548 // 549 // FIXME, this could be made much more efficient for large constant pools. 550 int Idx = V->getExistingMachineCPValue(this, Alignment); 551 if (Idx != -1) 552 return (unsigned)Idx; 553 554 Constants.push_back(MachineConstantPoolEntry(V, Alignment)); 555 return Constants.size()-1; 556 } 557 558 void MachineConstantPool::print(raw_ostream &OS) const { 559 for (unsigned i = 0, e = Constants.size(); i != e; ++i) { 560 OS << " <cp#" << i << "> is"; 561 if (Constants[i].isMachineConstantPoolEntry()) 562 Constants[i].Val.MachineCPVal->print(OS); 563 else 564 OS << *(Value*)Constants[i].Val.ConstVal; 565 OS << " , alignment=" << Constants[i].getAlignment(); 566 OS << "\n"; 567 } 568 } 569 570 void MachineConstantPool::dump() const { print(errs()); } 571