MachineFunction.cpp revision 43ed267db3512823a9698f810be4e64bee227270
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" 36using namespace llvm; 37 38namespace { 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/// 67FunctionPass *llvm::createMachineFunctionPrinterPass(raw_ostream &OS, 68 const std::string &Banner){ 69 return new Printer(OS, Banner); 70} 71 72//===---------------------------------------------------------------------===// 73// MachineFunction implementation 74//===---------------------------------------------------------------------===// 75 76void ilist_traits<MachineBasicBlock>::deleteNode(MachineBasicBlock *MBB) { 77 MBB->getParent()->DeleteMachineBasicBlock(MBB); 78} 79 80MachineFunction::MachineFunction(Function *F, 81 const TargetMachine &TM) 82 : Fn(F), Target(TM) { 83 if (TM.getRegisterInfo()) 84 RegInfo = new (Allocator.Allocate<MachineRegisterInfo>()) 85 MachineRegisterInfo(*TM.getRegisterInfo()); 86 else 87 RegInfo = 0; 88 MFInfo = 0; 89 FrameInfo = new (Allocator.Allocate<MachineFrameInfo>()) 90 MachineFrameInfo(*TM.getFrameInfo()); 91 ConstantPool = new (Allocator.Allocate<MachineConstantPool>()) 92 MachineConstantPool(TM.getTargetData()); 93 Alignment = TM.getTargetLowering()->getFunctionAlignment(F); 94 95 // Set up jump table. 96 const TargetData &TD = *TM.getTargetData(); 97 bool IsPic = TM.getRelocationModel() == Reloc::PIC_; 98 unsigned EntrySize = IsPic ? 4 : TD.getPointerSize(); 99 unsigned TyAlignment = IsPic ? 100 TD.getABITypeAlignment(Type::getInt32Ty(F->getContext())) 101 : TD.getPointerABIAlignment(); 102 JumpTableInfo = new (Allocator.Allocate<MachineJumpTableInfo>()) 103 MachineJumpTableInfo(EntrySize, TyAlignment); 104} 105 106MachineFunction::~MachineFunction() { 107 BasicBlocks.clear(); 108 InstructionRecycler.clear(Allocator); 109 BasicBlockRecycler.clear(Allocator); 110 if (RegInfo) { 111 RegInfo->~MachineRegisterInfo(); 112 Allocator.Deallocate(RegInfo); 113 } 114 if (MFInfo) { 115 MFInfo->~MachineFunctionInfo(); 116 Allocator.Deallocate(MFInfo); 117 } 118 FrameInfo->~MachineFrameInfo(); Allocator.Deallocate(FrameInfo); 119 ConstantPool->~MachineConstantPool(); Allocator.Deallocate(ConstantPool); 120 JumpTableInfo->~MachineJumpTableInfo(); Allocator.Deallocate(JumpTableInfo); 121} 122 123 124/// RenumberBlocks - This discards all of the MachineBasicBlock numbers and 125/// recomputes them. This guarantees that the MBB numbers are sequential, 126/// dense, and match the ordering of the blocks within the function. If a 127/// specific MachineBasicBlock is specified, only that block and those after 128/// it are renumbered. 129void MachineFunction::RenumberBlocks(MachineBasicBlock *MBB) { 130 if (empty()) { MBBNumbering.clear(); return; } 131 MachineFunction::iterator MBBI, E = end(); 132 if (MBB == 0) 133 MBBI = begin(); 134 else 135 MBBI = MBB; 136 137 // Figure out the block number this should have. 138 unsigned BlockNo = 0; 139 if (MBBI != begin()) 140 BlockNo = prior(MBBI)->getNumber()+1; 141 142 for (; MBBI != E; ++MBBI, ++BlockNo) { 143 if (MBBI->getNumber() != (int)BlockNo) { 144 // Remove use of the old number. 145 if (MBBI->getNumber() != -1) { 146 assert(MBBNumbering[MBBI->getNumber()] == &*MBBI && 147 "MBB number mismatch!"); 148 MBBNumbering[MBBI->getNumber()] = 0; 149 } 150 151 // If BlockNo is already taken, set that block's number to -1. 152 if (MBBNumbering[BlockNo]) 153 MBBNumbering[BlockNo]->setNumber(-1); 154 155 MBBNumbering[BlockNo] = MBBI; 156 MBBI->setNumber(BlockNo); 157 } 158 } 159 160 // Okay, all the blocks are renumbered. If we have compactified the block 161 // numbering, shrink MBBNumbering now. 162 assert(BlockNo <= MBBNumbering.size() && "Mismatch!"); 163 MBBNumbering.resize(BlockNo); 164} 165 166/// CreateMachineInstr - Allocate a new MachineInstr. Use this instead 167/// of `new MachineInstr'. 168/// 169MachineInstr * 170MachineFunction::CreateMachineInstr(const TargetInstrDesc &TID, 171 DebugLoc DL, bool NoImp) { 172 return new (InstructionRecycler.Allocate<MachineInstr>(Allocator)) 173 MachineInstr(TID, DL, NoImp); 174} 175 176/// CloneMachineInstr - Create a new MachineInstr which is a copy of the 177/// 'Orig' instruction, identical in all ways except the the instruction 178/// has no parent, prev, or next. 179/// 180MachineInstr * 181MachineFunction::CloneMachineInstr(const MachineInstr *Orig) { 182 return new (InstructionRecycler.Allocate<MachineInstr>(Allocator)) 183 MachineInstr(*this, *Orig); 184} 185 186/// DeleteMachineInstr - Delete the given MachineInstr. 187/// 188void 189MachineFunction::DeleteMachineInstr(MachineInstr *MI) { 190 // Clear the instructions memoperands. This must be done manually because 191 // the instruction's parent pointer is now null, so it can't properly 192 // deallocate them on its own. 193 MI->clearMemOperands(*this); 194 195 MI->~MachineInstr(); 196 InstructionRecycler.Deallocate(Allocator, MI); 197} 198 199/// CreateMachineBasicBlock - Allocate a new MachineBasicBlock. Use this 200/// instead of `new MachineBasicBlock'. 201/// 202MachineBasicBlock * 203MachineFunction::CreateMachineBasicBlock(const BasicBlock *bb) { 204 return new (BasicBlockRecycler.Allocate<MachineBasicBlock>(Allocator)) 205 MachineBasicBlock(*this, bb); 206} 207 208/// DeleteMachineBasicBlock - Delete the given MachineBasicBlock. 209/// 210void 211MachineFunction::DeleteMachineBasicBlock(MachineBasicBlock *MBB) { 212 assert(MBB->getParent() == this && "MBB parent mismatch!"); 213 MBB->~MachineBasicBlock(); 214 BasicBlockRecycler.Deallocate(Allocator, MBB); 215} 216 217void MachineFunction::dump() const { 218 print(errs()); 219} 220 221void MachineFunction::print(raw_ostream &OS) const { 222 OS << "# Machine code for " << Fn->getName() << "():\n"; 223 224 // Print Frame Information 225 FrameInfo->print(*this, OS); 226 227 // Print JumpTable Information 228 JumpTableInfo->print(OS); 229 230 // Print Constant Pool 231 ConstantPool->print(OS); 232 233 const TargetRegisterInfo *TRI = getTarget().getRegisterInfo(); 234 235 if (RegInfo && !RegInfo->livein_empty()) { 236 OS << "Live Ins:"; 237 for (MachineRegisterInfo::livein_iterator 238 I = RegInfo->livein_begin(), E = RegInfo->livein_end(); I != E; ++I) { 239 if (TRI) 240 OS << " " << TRI->getName(I->first); 241 else 242 OS << " Reg #" << I->first; 243 244 if (I->second) 245 OS << " in VR#" << I->second << ' '; 246 } 247 OS << '\n'; 248 } 249 if (RegInfo && !RegInfo->liveout_empty()) { 250 OS << "Live Outs:"; 251 for (MachineRegisterInfo::liveout_iterator 252 I = RegInfo->liveout_begin(), E = RegInfo->liveout_end(); I != E; ++I) 253 if (TRI) 254 OS << ' ' << TRI->getName(*I); 255 else 256 OS << " Reg #" << *I; 257 OS << '\n'; 258 } 259 260 for (const_iterator BB = begin(), E = end(); BB != E; ++BB) 261 BB->print(OS); 262 263 OS << "\n# End machine code for " << Fn->getName() << "().\n\n"; 264} 265 266namespace llvm { 267 template<> 268 struct DOTGraphTraits<const MachineFunction*> : public DefaultDOTGraphTraits { 269 static std::string getGraphName(const MachineFunction *F) { 270 return "CFG for '" + F->getFunction()->getNameStr() + "' function"; 271 } 272 273 static std::string getNodeLabel(const MachineBasicBlock *Node, 274 const MachineFunction *Graph, 275 bool ShortNames) { 276 if (ShortNames && Node->getBasicBlock() && 277 !Node->getBasicBlock()->getName().empty()) 278 return Node->getBasicBlock()->getNameStr() + ":"; 279 280 std::string OutStr; 281 { 282 raw_string_ostream OSS(OutStr); 283 284 if (ShortNames) 285 OSS << Node->getNumber() << ':'; 286 else 287 Node->print(OSS); 288 } 289 290 if (OutStr[0] == '\n') OutStr.erase(OutStr.begin()); 291 292 // Process string output to make it nicer... 293 for (unsigned i = 0; i != OutStr.length(); ++i) 294 if (OutStr[i] == '\n') { // Left justify 295 OutStr[i] = '\\'; 296 OutStr.insert(OutStr.begin()+i+1, 'l'); 297 } 298 return OutStr; 299 } 300 }; 301} 302 303void MachineFunction::viewCFG() const 304{ 305#ifndef NDEBUG 306 ViewGraph(this, "mf" + getFunction()->getNameStr()); 307#else 308 errs() << "SelectionDAG::viewGraph is only available in debug builds on " 309 << "systems with Graphviz or gv!\n"; 310#endif // NDEBUG 311} 312 313void MachineFunction::viewCFGOnly() const 314{ 315#ifndef NDEBUG 316 ViewGraph(this, "mf" + getFunction()->getNameStr(), true); 317#else 318 errs() << "SelectionDAG::viewGraph is only available in debug builds on " 319 << "systems with Graphviz or gv!\n"; 320#endif // NDEBUG 321} 322 323/// addLiveIn - Add the specified physical register as a live-in value and 324/// create a corresponding virtual register for it. 325unsigned MachineFunction::addLiveIn(unsigned PReg, 326 const TargetRegisterClass *RC) { 327 assert(RC->contains(PReg) && "Not the correct regclass!"); 328 unsigned VReg = getRegInfo().createVirtualRegister(RC); 329 getRegInfo().addLiveIn(PReg, VReg); 330 return VReg; 331} 332 333/// getOrCreateDebugLocID - Look up the DebugLocTuple index with the given 334/// source file, line, and column. If none currently exists, create a new 335/// DebugLocTuple, and insert it into the DebugIdMap. 336unsigned MachineFunction::getOrCreateDebugLocID(GlobalVariable *CompileUnit, 337 unsigned Line, unsigned Col) { 338 DebugLocTuple Tuple(CompileUnit, Line, Col); 339 DenseMap<DebugLocTuple, unsigned>::iterator II 340 = DebugLocInfo.DebugIdMap.find(Tuple); 341 if (II != DebugLocInfo.DebugIdMap.end()) 342 return II->second; 343 // Add a new tuple. 344 unsigned Id = DebugLocInfo.DebugLocations.size(); 345 DebugLocInfo.DebugLocations.push_back(Tuple); 346 DebugLocInfo.DebugIdMap[Tuple] = Id; 347 return Id; 348} 349 350/// getDebugLocTuple - Get the DebugLocTuple for a given DebugLoc object. 351DebugLocTuple MachineFunction::getDebugLocTuple(DebugLoc DL) const { 352 unsigned Idx = DL.getIndex(); 353 assert(Idx < DebugLocInfo.DebugLocations.size() && 354 "Invalid index into debug locations!"); 355 return DebugLocInfo.DebugLocations[Idx]; 356} 357 358//===----------------------------------------------------------------------===// 359// MachineFrameInfo implementation 360//===----------------------------------------------------------------------===// 361 362/// CreateFixedObject - Create a new object at a fixed location on the stack. 363/// All fixed objects should be created before other objects are created for 364/// efficiency. By default, fixed objects are immutable. This returns an 365/// index with a negative value. 366/// 367int MachineFrameInfo::CreateFixedObject(uint64_t Size, int64_t SPOffset, 368 bool Immutable) { 369 assert(Size != 0 && "Cannot allocate zero size fixed stack objects!"); 370 Objects.insert(Objects.begin(), StackObject(Size, 1, SPOffset, Immutable)); 371 return -++NumFixedObjects; 372} 373 374 375BitVector 376MachineFrameInfo::getPristineRegs(const MachineBasicBlock *MBB) const { 377 assert(MBB && "MBB must be valid"); 378 const MachineFunction *MF = MBB->getParent(); 379 assert(MF && "MBB must be part of a MachineFunction"); 380 const TargetMachine &TM = MF->getTarget(); 381 const TargetRegisterInfo *TRI = TM.getRegisterInfo(); 382 BitVector BV(TRI->getNumRegs()); 383 384 // Before CSI is calculated, no registers are considered pristine. They can be 385 // freely used and PEI will make sure they are saved. 386 if (!isCalleeSavedInfoValid()) 387 return BV; 388 389 for (const unsigned *CSR = TRI->getCalleeSavedRegs(MF); CSR && *CSR; ++CSR) 390 BV.set(*CSR); 391 392 // The entry MBB always has all CSRs pristine. 393 if (MBB == &MF->front()) 394 return BV; 395 396 // On other MBBs the saved CSRs are not pristine. 397 const std::vector<CalleeSavedInfo> &CSI = getCalleeSavedInfo(); 398 for (std::vector<CalleeSavedInfo>::const_iterator I = CSI.begin(), 399 E = CSI.end(); I != E; ++I) 400 BV.reset(I->getReg()); 401 402 return BV; 403} 404 405 406void MachineFrameInfo::print(const MachineFunction &MF, raw_ostream &OS) const{ 407 const TargetFrameInfo *FI = MF.getTarget().getFrameInfo(); 408 int ValOffset = (FI ? FI->getOffsetOfLocalArea() : 0); 409 410 for (unsigned i = 0, e = Objects.size(); i != e; ++i) { 411 const StackObject &SO = Objects[i]; 412 OS << " <fi#" << (int)(i-NumFixedObjects) << ">: "; 413 if (SO.Size == ~0ULL) { 414 OS << "dead\n"; 415 continue; 416 } 417 if (SO.Size == 0) 418 OS << "variable sized"; 419 else 420 OS << "size is " << SO.Size << " byte" << (SO.Size != 1 ? "s," : ","); 421 OS << " alignment is " << SO.Alignment << " byte" 422 << (SO.Alignment != 1 ? "s," : ","); 423 424 if (i < NumFixedObjects) 425 OS << " fixed"; 426 if (i < NumFixedObjects || SO.SPOffset != -1) { 427 int64_t Off = SO.SPOffset - ValOffset; 428 OS << " at location [SP"; 429 if (Off > 0) 430 OS << "+" << Off; 431 else if (Off < 0) 432 OS << Off; 433 OS << "]"; 434 } 435 OS << "\n"; 436 } 437 438 if (HasVarSizedObjects) 439 OS << " Stack frame contains variable sized objects\n"; 440} 441 442void MachineFrameInfo::dump(const MachineFunction &MF) const { 443 print(MF, errs()); 444} 445 446//===----------------------------------------------------------------------===// 447// MachineJumpTableInfo implementation 448//===----------------------------------------------------------------------===// 449 450/// getJumpTableIndex - Create a new jump table entry in the jump table info 451/// or return an existing one. 452/// 453unsigned MachineJumpTableInfo::getJumpTableIndex( 454 const std::vector<MachineBasicBlock*> &DestBBs) { 455 assert(!DestBBs.empty() && "Cannot create an empty jump table!"); 456 for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) 457 if (JumpTables[i].MBBs == DestBBs) 458 return i; 459 460 JumpTables.push_back(MachineJumpTableEntry(DestBBs)); 461 return JumpTables.size()-1; 462} 463 464/// ReplaceMBBInJumpTables - If Old is the target of any jump tables, update 465/// the jump tables to branch to New instead. 466bool 467MachineJumpTableInfo::ReplaceMBBInJumpTables(MachineBasicBlock *Old, 468 MachineBasicBlock *New) { 469 assert(Old != New && "Not making a change?"); 470 bool MadeChange = false; 471 for (size_t i = 0, e = JumpTables.size(); i != e; ++i) { 472 MachineJumpTableEntry &JTE = JumpTables[i]; 473 for (size_t j = 0, e = JTE.MBBs.size(); j != e; ++j) 474 if (JTE.MBBs[j] == Old) { 475 JTE.MBBs[j] = New; 476 MadeChange = true; 477 } 478 } 479 return MadeChange; 480} 481 482void MachineJumpTableInfo::print(raw_ostream &OS) const { 483 // FIXME: this is lame, maybe we could print out the MBB numbers or something 484 // like {1, 2, 4, 5, 3, 0} 485 for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) { 486 OS << " <jt#" << i << "> has " << JumpTables[i].MBBs.size() 487 << " entries\n"; 488 } 489} 490 491void MachineJumpTableInfo::dump() const { print(errs()); } 492 493 494//===----------------------------------------------------------------------===// 495// MachineConstantPool implementation 496//===----------------------------------------------------------------------===// 497 498const Type *MachineConstantPoolEntry::getType() const { 499 if (isMachineConstantPoolEntry()) 500 return Val.MachineCPVal->getType(); 501 return Val.ConstVal->getType(); 502} 503 504 505unsigned MachineConstantPoolEntry::getRelocationInfo() const { 506 if (isMachineConstantPoolEntry()) 507 return Val.MachineCPVal->getRelocationInfo(); 508 return Val.ConstVal->getRelocationInfo(); 509} 510 511MachineConstantPool::~MachineConstantPool() { 512 for (unsigned i = 0, e = Constants.size(); i != e; ++i) 513 if (Constants[i].isMachineConstantPoolEntry()) 514 delete Constants[i].Val.MachineCPVal; 515} 516 517/// getConstantPoolIndex - Create a new entry in the constant pool or return 518/// an existing one. User must specify the log2 of the minimum required 519/// alignment for the object. 520/// 521unsigned MachineConstantPool::getConstantPoolIndex(Constant *C, 522 unsigned Alignment) { 523 assert(Alignment && "Alignment must be specified!"); 524 if (Alignment > PoolAlignment) PoolAlignment = Alignment; 525 526 // Check to see if we already have this constant. 527 // 528 // FIXME, this could be made much more efficient for large constant pools. 529 for (unsigned i = 0, e = Constants.size(); i != e; ++i) 530 if (Constants[i].Val.ConstVal == C && 531 (Constants[i].getAlignment() & (Alignment - 1)) == 0) 532 return i; 533 534 Constants.push_back(MachineConstantPoolEntry(C, Alignment)); 535 return Constants.size()-1; 536} 537 538unsigned MachineConstantPool::getConstantPoolIndex(MachineConstantPoolValue *V, 539 unsigned Alignment) { 540 assert(Alignment && "Alignment must be specified!"); 541 if (Alignment > PoolAlignment) PoolAlignment = Alignment; 542 543 // Check to see if we already have this constant. 544 // 545 // FIXME, this could be made much more efficient for large constant pools. 546 int Idx = V->getExistingMachineCPValue(this, Alignment); 547 if (Idx != -1) 548 return (unsigned)Idx; 549 550 Constants.push_back(MachineConstantPoolEntry(V, Alignment)); 551 return Constants.size()-1; 552} 553 554void MachineConstantPool::print(raw_ostream &OS) const { 555 for (unsigned i = 0, e = Constants.size(); i != e; ++i) { 556 OS << " <cp#" << i << "> is"; 557 if (Constants[i].isMachineConstantPoolEntry()) 558 Constants[i].Val.MachineCPVal->print(OS); 559 else 560 OS << *(Value*)Constants[i].Val.ConstVal; 561 OS << " , alignment=" << Constants[i].getAlignment(); 562 OS << "\n"; 563 } 564} 565 566void MachineConstantPool::dump() const { print(errs()); } 567