MachineFunction.cpp revision d74c556e9aaad81a188158b7ba12d7ccffb30936
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#include <fstream> 37#include <sstream> 38using namespace llvm; 39 40namespace { 41 struct VISIBILITY_HIDDEN Printer : public MachineFunctionPass { 42 static char ID; 43 44 std::ostream *OS; 45 const std::string Banner; 46 47 Printer(std::ostream *os, const std::string &banner) 48 : MachineFunctionPass(&ID), OS(os), Banner(banner) {} 49 50 const char *getPassName() const { return "MachineFunction Printer"; } 51 52 virtual void getAnalysisUsage(AnalysisUsage &AU) const { 53 AU.setPreservesAll(); 54 MachineFunctionPass::getAnalysisUsage(AU); 55 } 56 57 bool runOnMachineFunction(MachineFunction &MF) { 58 (*OS) << Banner; 59 MF.print (*OS); 60 return false; 61 } 62 }; 63 char Printer::ID = 0; 64} 65 66/// Returns a newly-created MachineFunction Printer pass. The default banner is 67/// empty. 68/// 69FunctionPass *llvm::createMachineFunctionPrinterPass(std::ostream *OS, 70 const std::string &Banner){ 71 return new Printer(OS, Banner); 72} 73 74//===---------------------------------------------------------------------===// 75// MachineFunction implementation 76//===---------------------------------------------------------------------===// 77 78void ilist_traits<MachineBasicBlock>::deleteNode(MachineBasicBlock *MBB) { 79 MBB->getParent()->DeleteMachineBasicBlock(MBB); 80} 81 82MachineFunction::MachineFunction(Function *F, 83 const TargetMachine &TM) 84 : Fn(F), Target(TM) { 85 if (TM.getRegisterInfo()) 86 RegInfo = new (Allocator.Allocate<MachineRegisterInfo>()) 87 MachineRegisterInfo(*TM.getRegisterInfo()); 88 else 89 RegInfo = 0; 90 MFInfo = 0; 91 FrameInfo = new (Allocator.Allocate<MachineFrameInfo>()) 92 MachineFrameInfo(*TM.getFrameInfo()); 93 ConstantPool = new (Allocator.Allocate<MachineConstantPool>()) 94 MachineConstantPool(TM.getTargetData()); 95 Alignment = TM.getTargetLowering()->getFunctionAlignment(F); 96 97 // Set up jump table. 98 const TargetData &TD = *TM.getTargetData(); 99 bool IsPic = TM.getRelocationModel() == Reloc::PIC_; 100 unsigned EntrySize = IsPic ? 4 : TD.getPointerSize(); 101 unsigned TyAlignment = IsPic ? 102 TD.getABITypeAlignment(Type::getInt32Ty(F->getContext())) 103 : TD.getPointerABIAlignment(); 104 JumpTableInfo = new (Allocator.Allocate<MachineJumpTableInfo>()) 105 MachineJumpTableInfo(EntrySize, TyAlignment); 106} 107 108MachineFunction::~MachineFunction() { 109 BasicBlocks.clear(); 110 InstructionRecycler.clear(Allocator); 111 BasicBlockRecycler.clear(Allocator); 112 if (RegInfo) { 113 RegInfo->~MachineRegisterInfo(); 114 Allocator.Deallocate(RegInfo); 115 } 116 if (MFInfo) { 117 MFInfo->~MachineFunctionInfo(); 118 Allocator.Deallocate(MFInfo); 119 } 120 FrameInfo->~MachineFrameInfo(); Allocator.Deallocate(FrameInfo); 121 ConstantPool->~MachineConstantPool(); Allocator.Deallocate(ConstantPool); 122 JumpTableInfo->~MachineJumpTableInfo(); Allocator.Deallocate(JumpTableInfo); 123} 124 125 126/// RenumberBlocks - This discards all of the MachineBasicBlock numbers and 127/// recomputes them. This guarantees that the MBB numbers are sequential, 128/// dense, and match the ordering of the blocks within the function. If a 129/// specific MachineBasicBlock is specified, only that block and those after 130/// it are renumbered. 131void MachineFunction::RenumberBlocks(MachineBasicBlock *MBB) { 132 if (empty()) { MBBNumbering.clear(); return; } 133 MachineFunction::iterator MBBI, E = end(); 134 if (MBB == 0) 135 MBBI = begin(); 136 else 137 MBBI = MBB; 138 139 // Figure out the block number this should have. 140 unsigned BlockNo = 0; 141 if (MBBI != begin()) 142 BlockNo = prior(MBBI)->getNumber()+1; 143 144 for (; MBBI != E; ++MBBI, ++BlockNo) { 145 if (MBBI->getNumber() != (int)BlockNo) { 146 // Remove use of the old number. 147 if (MBBI->getNumber() != -1) { 148 assert(MBBNumbering[MBBI->getNumber()] == &*MBBI && 149 "MBB number mismatch!"); 150 MBBNumbering[MBBI->getNumber()] = 0; 151 } 152 153 // If BlockNo is already taken, set that block's number to -1. 154 if (MBBNumbering[BlockNo]) 155 MBBNumbering[BlockNo]->setNumber(-1); 156 157 MBBNumbering[BlockNo] = MBBI; 158 MBBI->setNumber(BlockNo); 159 } 160 } 161 162 // Okay, all the blocks are renumbered. If we have compactified the block 163 // numbering, shrink MBBNumbering now. 164 assert(BlockNo <= MBBNumbering.size() && "Mismatch!"); 165 MBBNumbering.resize(BlockNo); 166} 167 168/// CreateMachineInstr - Allocate a new MachineInstr. Use this instead 169/// of `new MachineInstr'. 170/// 171MachineInstr * 172MachineFunction::CreateMachineInstr(const TargetInstrDesc &TID, 173 DebugLoc DL, bool NoImp) { 174 return new (InstructionRecycler.Allocate<MachineInstr>(Allocator)) 175 MachineInstr(TID, DL, NoImp); 176} 177 178/// CloneMachineInstr - Create a new MachineInstr which is a copy of the 179/// 'Orig' instruction, identical in all ways except the the instruction 180/// has no parent, prev, or next. 181/// 182MachineInstr * 183MachineFunction::CloneMachineInstr(const MachineInstr *Orig) { 184 return new (InstructionRecycler.Allocate<MachineInstr>(Allocator)) 185 MachineInstr(*this, *Orig); 186} 187 188/// DeleteMachineInstr - Delete the given MachineInstr. 189/// 190void 191MachineFunction::DeleteMachineInstr(MachineInstr *MI) { 192 // Clear the instructions memoperands. This must be done manually because 193 // the instruction's parent pointer is now null, so it can't properly 194 // deallocate them on its own. 195 MI->clearMemOperands(*this); 196 197 MI->~MachineInstr(); 198 InstructionRecycler.Deallocate(Allocator, MI); 199} 200 201/// CreateMachineBasicBlock - Allocate a new MachineBasicBlock. Use this 202/// instead of `new MachineBasicBlock'. 203/// 204MachineBasicBlock * 205MachineFunction::CreateMachineBasicBlock(const BasicBlock *bb) { 206 return new (BasicBlockRecycler.Allocate<MachineBasicBlock>(Allocator)) 207 MachineBasicBlock(*this, bb); 208} 209 210/// DeleteMachineBasicBlock - Delete the given MachineBasicBlock. 211/// 212void 213MachineFunction::DeleteMachineBasicBlock(MachineBasicBlock *MBB) { 214 assert(MBB->getParent() == this && "MBB parent mismatch!"); 215 MBB->~MachineBasicBlock(); 216 BasicBlockRecycler.Deallocate(Allocator, MBB); 217} 218 219void MachineFunction::dump() const { 220 print(errs()); 221} 222 223void MachineFunction::print(std::ostream &OS) const { 224 raw_os_ostream RawOS(OS); 225 print(RawOS); 226} 227 228void MachineFunction::print(raw_ostream &OS) const { 229 OS << "# Machine code for " << Fn->getName() << "():\n"; 230 231 // Print Frame Information 232 FrameInfo->print(*this, OS); 233 234 // Print JumpTable Information 235 JumpTableInfo->print(OS); 236 237 // Print Constant Pool 238 ConstantPool->print(OS); 239 240 const TargetRegisterInfo *TRI = getTarget().getRegisterInfo(); 241 242 if (RegInfo && !RegInfo->livein_empty()) { 243 OS << "Live Ins:"; 244 for (MachineRegisterInfo::livein_iterator 245 I = RegInfo->livein_begin(), E = RegInfo->livein_end(); I != E; ++I) { 246 if (TRI) 247 OS << " " << TRI->getName(I->first); 248 else 249 OS << " Reg #" << I->first; 250 251 if (I->second) 252 OS << " in VR#" << I->second << ' '; 253 } 254 OS << '\n'; 255 } 256 if (RegInfo && !RegInfo->liveout_empty()) { 257 OS << "Live Outs:"; 258 for (MachineRegisterInfo::liveout_iterator 259 I = RegInfo->liveout_begin(), E = RegInfo->liveout_end(); I != E; ++I) 260 if (TRI) 261 OS << ' ' << TRI->getName(*I); 262 else 263 OS << " Reg #" << *I; 264 OS << '\n'; 265 } 266 267 for (const_iterator BB = begin(), E = end(); BB != E; ++BB) 268 BB->print(OS); 269 270 OS << "\n# End machine code for " << Fn->getName() << "().\n\n"; 271} 272 273namespace llvm { 274 template<> 275 struct DOTGraphTraits<const MachineFunction*> : public DefaultDOTGraphTraits { 276 static std::string getGraphName(const MachineFunction *F) { 277 return "CFG for '" + F->getFunction()->getNameStr() + "' function"; 278 } 279 280 static std::string getNodeLabel(const MachineBasicBlock *Node, 281 const MachineFunction *Graph, 282 bool ShortNames) { 283 if (ShortNames && Node->getBasicBlock() && 284 !Node->getBasicBlock()->getName().empty()) 285 return Node->getBasicBlock()->getNameStr() + ":"; 286 287 std::ostringstream Out; 288 if (ShortNames) { 289 Out << Node->getNumber() << ':'; 290 return Out.str(); 291 } 292 293 Node->print(Out); 294 295 std::string OutStr = Out.str(); 296 if (OutStr[0] == '\n') OutStr.erase(OutStr.begin()); 297 298 // Process string output to make it nicer... 299 for (unsigned i = 0; i != OutStr.length(); ++i) 300 if (OutStr[i] == '\n') { // Left justify 301 OutStr[i] = '\\'; 302 OutStr.insert(OutStr.begin()+i+1, 'l'); 303 } 304 return OutStr; 305 } 306 }; 307} 308 309void MachineFunction::viewCFG() const 310{ 311#ifndef NDEBUG 312 ViewGraph(this, "mf" + getFunction()->getNameStr()); 313#else 314 cerr << "SelectionDAG::viewGraph is only available in debug builds on " 315 << "systems with Graphviz or gv!\n"; 316#endif // NDEBUG 317} 318 319void MachineFunction::viewCFGOnly() const 320{ 321#ifndef NDEBUG 322 ViewGraph(this, "mf" + getFunction()->getNameStr(), true); 323#else 324 cerr << "SelectionDAG::viewGraph is only available in debug builds on " 325 << "systems with Graphviz or gv!\n"; 326#endif // NDEBUG 327} 328 329/// addLiveIn - Add the specified physical register as a live-in value and 330/// create a corresponding virtual register for it. 331unsigned MachineFunction::addLiveIn(unsigned PReg, 332 const TargetRegisterClass *RC) { 333 assert(RC->contains(PReg) && "Not the correct regclass!"); 334 unsigned VReg = getRegInfo().createVirtualRegister(RC); 335 getRegInfo().addLiveIn(PReg, VReg); 336 return VReg; 337} 338 339/// getOrCreateDebugLocID - Look up the DebugLocTuple index with the given 340/// source file, line, and column. If none currently exists, create a new 341/// DebugLocTuple, and insert it into the DebugIdMap. 342unsigned MachineFunction::getOrCreateDebugLocID(GlobalVariable *CompileUnit, 343 unsigned Line, unsigned Col) { 344 DebugLocTuple Tuple(CompileUnit, Line, Col); 345 DenseMap<DebugLocTuple, unsigned>::iterator II 346 = DebugLocInfo.DebugIdMap.find(Tuple); 347 if (II != DebugLocInfo.DebugIdMap.end()) 348 return II->second; 349 // Add a new tuple. 350 unsigned Id = DebugLocInfo.DebugLocations.size(); 351 DebugLocInfo.DebugLocations.push_back(Tuple); 352 DebugLocInfo.DebugIdMap[Tuple] = Id; 353 return Id; 354} 355 356/// getDebugLocTuple - Get the DebugLocTuple for a given DebugLoc object. 357DebugLocTuple MachineFunction::getDebugLocTuple(DebugLoc DL) const { 358 unsigned Idx = DL.getIndex(); 359 assert(Idx < DebugLocInfo.DebugLocations.size() && 360 "Invalid index into debug locations!"); 361 return DebugLocInfo.DebugLocations[Idx]; 362} 363 364//===----------------------------------------------------------------------===// 365// MachineFrameInfo implementation 366//===----------------------------------------------------------------------===// 367 368/// CreateFixedObject - Create a new object at a fixed location on the stack. 369/// All fixed objects should be created before other objects are created for 370/// efficiency. By default, fixed objects are immutable. This returns an 371/// index with a negative value. 372/// 373int MachineFrameInfo::CreateFixedObject(uint64_t Size, int64_t SPOffset, 374 bool Immutable) { 375 assert(Size != 0 && "Cannot allocate zero size fixed stack objects!"); 376 Objects.insert(Objects.begin(), StackObject(Size, 1, SPOffset, Immutable)); 377 return -++NumFixedObjects; 378} 379 380 381BitVector 382MachineFrameInfo::getPristineRegs(const MachineBasicBlock *MBB) const { 383 assert(MBB && "MBB must be valid"); 384 const MachineFunction *MF = MBB->getParent(); 385 assert(MF && "MBB must be part of a MachineFunction"); 386 const TargetMachine &TM = MF->getTarget(); 387 const TargetRegisterInfo *TRI = TM.getRegisterInfo(); 388 BitVector BV(TRI->getNumRegs()); 389 390 // Before CSI is calculated, no registers are considered pristine. They can be 391 // freely used and PEI will make sure they are saved. 392 if (!isCalleeSavedInfoValid()) 393 return BV; 394 395 for (const unsigned *CSR = TRI->getCalleeSavedRegs(MF); CSR && *CSR; ++CSR) 396 BV.set(*CSR); 397 398 // The entry MBB always has all CSRs pristine. 399 if (MBB == &MF->front()) 400 return BV; 401 402 // On other MBBs the saved CSRs are not pristine. 403 const std::vector<CalleeSavedInfo> &CSI = getCalleeSavedInfo(); 404 for (std::vector<CalleeSavedInfo>::const_iterator I = CSI.begin(), 405 E = CSI.end(); I != E; ++I) 406 BV.reset(I->getReg()); 407 408 return BV; 409} 410 411 412void MachineFrameInfo::print(const MachineFunction &MF, raw_ostream &OS) const{ 413 const TargetFrameInfo *FI = MF.getTarget().getFrameInfo(); 414 int ValOffset = (FI ? FI->getOffsetOfLocalArea() : 0); 415 416 for (unsigned i = 0, e = Objects.size(); i != e; ++i) { 417 const StackObject &SO = Objects[i]; 418 OS << " <fi#" << (int)(i-NumFixedObjects) << ">: "; 419 if (SO.Size == ~0ULL) { 420 OS << "dead\n"; 421 continue; 422 } 423 if (SO.Size == 0) 424 OS << "variable sized"; 425 else 426 OS << "size is " << SO.Size << " byte" << (SO.Size != 1 ? "s," : ","); 427 OS << " alignment is " << SO.Alignment << " byte" 428 << (SO.Alignment != 1 ? "s," : ","); 429 430 if (i < NumFixedObjects) 431 OS << " fixed"; 432 if (i < NumFixedObjects || SO.SPOffset != -1) { 433 int64_t Off = SO.SPOffset - ValOffset; 434 OS << " at location [SP"; 435 if (Off > 0) 436 OS << "+" << Off; 437 else if (Off < 0) 438 OS << Off; 439 OS << "]"; 440 } 441 OS << "\n"; 442 } 443 444 if (HasVarSizedObjects) 445 OS << " Stack frame contains variable sized objects\n"; 446} 447 448void MachineFrameInfo::dump(const MachineFunction &MF) const { 449 print(MF, errs()); 450} 451 452//===----------------------------------------------------------------------===// 453// MachineJumpTableInfo implementation 454//===----------------------------------------------------------------------===// 455 456/// getJumpTableIndex - Create a new jump table entry in the jump table info 457/// or return an existing one. 458/// 459unsigned MachineJumpTableInfo::getJumpTableIndex( 460 const std::vector<MachineBasicBlock*> &DestBBs) { 461 assert(!DestBBs.empty() && "Cannot create an empty jump table!"); 462 for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) 463 if (JumpTables[i].MBBs == DestBBs) 464 return i; 465 466 JumpTables.push_back(MachineJumpTableEntry(DestBBs)); 467 return JumpTables.size()-1; 468} 469 470/// ReplaceMBBInJumpTables - If Old is the target of any jump tables, update 471/// the jump tables to branch to New instead. 472bool 473MachineJumpTableInfo::ReplaceMBBInJumpTables(MachineBasicBlock *Old, 474 MachineBasicBlock *New) { 475 assert(Old != New && "Not making a change?"); 476 bool MadeChange = false; 477 for (size_t i = 0, e = JumpTables.size(); i != e; ++i) { 478 MachineJumpTableEntry &JTE = JumpTables[i]; 479 for (size_t j = 0, e = JTE.MBBs.size(); j != e; ++j) 480 if (JTE.MBBs[j] == Old) { 481 JTE.MBBs[j] = New; 482 MadeChange = true; 483 } 484 } 485 return MadeChange; 486} 487 488void MachineJumpTableInfo::print(raw_ostream &OS) const { 489 // FIXME: this is lame, maybe we could print out the MBB numbers or something 490 // like {1, 2, 4, 5, 3, 0} 491 for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) { 492 OS << " <jt#" << i << "> has " << JumpTables[i].MBBs.size() 493 << " entries\n"; 494 } 495} 496 497void MachineJumpTableInfo::dump() const { print(errs()); } 498 499 500//===----------------------------------------------------------------------===// 501// MachineConstantPool implementation 502//===----------------------------------------------------------------------===// 503 504const Type *MachineConstantPoolEntry::getType() const { 505 if (isMachineConstantPoolEntry()) 506 return Val.MachineCPVal->getType(); 507 return Val.ConstVal->getType(); 508} 509 510 511unsigned MachineConstantPoolEntry::getRelocationInfo() const { 512 if (isMachineConstantPoolEntry()) 513 return Val.MachineCPVal->getRelocationInfo(); 514 return Val.ConstVal->getRelocationInfo(); 515} 516 517MachineConstantPool::~MachineConstantPool() { 518 for (unsigned i = 0, e = Constants.size(); i != e; ++i) 519 if (Constants[i].isMachineConstantPoolEntry()) 520 delete Constants[i].Val.MachineCPVal; 521} 522 523/// getConstantPoolIndex - Create a new entry in the constant pool or return 524/// an existing one. User must specify the log2 of the minimum required 525/// alignment for the object. 526/// 527unsigned MachineConstantPool::getConstantPoolIndex(Constant *C, 528 unsigned Alignment) { 529 assert(Alignment && "Alignment must be specified!"); 530 if (Alignment > PoolAlignment) PoolAlignment = Alignment; 531 532 // Check to see if we already have this constant. 533 // 534 // FIXME, this could be made much more efficient for large constant pools. 535 for (unsigned i = 0, e = Constants.size(); i != e; ++i) 536 if (Constants[i].Val.ConstVal == C && 537 (Constants[i].getAlignment() & (Alignment - 1)) == 0) 538 return i; 539 540 Constants.push_back(MachineConstantPoolEntry(C, Alignment)); 541 return Constants.size()-1; 542} 543 544unsigned MachineConstantPool::getConstantPoolIndex(MachineConstantPoolValue *V, 545 unsigned Alignment) { 546 assert(Alignment && "Alignment must be specified!"); 547 if (Alignment > PoolAlignment) PoolAlignment = Alignment; 548 549 // Check to see if we already have this constant. 550 // 551 // FIXME, this could be made much more efficient for large constant pools. 552 int Idx = V->getExistingMachineCPValue(this, Alignment); 553 if (Idx != -1) 554 return (unsigned)Idx; 555 556 Constants.push_back(MachineConstantPoolEntry(V, Alignment)); 557 return Constants.size()-1; 558} 559 560void MachineConstantPool::print(raw_ostream &OS) const { 561 for (unsigned i = 0, e = Constants.size(); i != e; ++i) { 562 OS << " <cp#" << i << "> is"; 563 if (Constants[i].isMachineConstantPoolEntry()) 564 Constants[i].Val.MachineCPVal->print(OS); 565 else 566 OS << *(Value*)Constants[i].Val.ConstVal; 567 OS << " , alignment=" << Constants[i].getAlignment(); 568 OS << "\n"; 569 } 570} 571 572void MachineConstantPool::dump() const { print(errs()); } 573