MachineFunction.cpp revision 195098
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> 36using namespace llvm; 37 38bool MachineFunctionPass::runOnFunction(Function &F) { 39 // Do not codegen any 'available_externally' functions at all, they have 40 // definitions outside the translation unit. 41 if (F.hasAvailableExternallyLinkage()) 42 return false; 43 44 return runOnMachineFunction(MachineFunction::get(&F)); 45} 46 47namespace { 48 struct VISIBILITY_HIDDEN Printer : public MachineFunctionPass { 49 static char ID; 50 51 std::ostream *OS; 52 const std::string Banner; 53 54 Printer (std::ostream *os, const std::string &banner) 55 : MachineFunctionPass(&ID), OS(os), Banner(banner) {} 56 57 const char *getPassName() const { return "MachineFunction Printer"; } 58 59 virtual void getAnalysisUsage(AnalysisUsage &AU) const { 60 AU.setPreservesAll(); 61 } 62 63 bool runOnMachineFunction(MachineFunction &MF) { 64 (*OS) << Banner; 65 MF.print (*OS); 66 return false; 67 } 68 }; 69 char Printer::ID = 0; 70} 71 72/// Returns a newly-created MachineFunction Printer pass. The default output 73/// stream is std::cerr; the default banner is empty. 74/// 75FunctionPass *llvm::createMachineFunctionPrinterPass(std::ostream *OS, 76 const std::string &Banner){ 77 return new Printer(OS, Banner); 78} 79 80namespace { 81 struct VISIBILITY_HIDDEN Deleter : public MachineFunctionPass { 82 static char ID; 83 Deleter() : MachineFunctionPass(&ID) {} 84 85 const char *getPassName() const { return "Machine Code Deleter"; } 86 87 bool runOnMachineFunction(MachineFunction &MF) { 88 // Delete the annotation from the function now. 89 MachineFunction::destruct(MF.getFunction()); 90 return true; 91 } 92 }; 93 char Deleter::ID = 0; 94} 95 96/// MachineCodeDeletion Pass - This pass deletes all of the machine code for 97/// the current function, which should happen after the function has been 98/// emitted to a .s file or to memory. 99FunctionPass *llvm::createMachineCodeDeleter() { 100 return new Deleter(); 101} 102 103 104 105//===---------------------------------------------------------------------===// 106// MachineFunction implementation 107//===---------------------------------------------------------------------===// 108 109void ilist_traits<MachineBasicBlock>::deleteNode(MachineBasicBlock *MBB) { 110 MBB->getParent()->DeleteMachineBasicBlock(MBB); 111} 112 113MachineFunction::MachineFunction(const Function *F, 114 const TargetMachine &TM) 115 : Annotation(AnnotationManager::getID("CodeGen::MachineCodeForFunction")), 116 Fn(F), Target(TM) { 117 if (TM.getRegisterInfo()) 118 RegInfo = new (Allocator.Allocate<MachineRegisterInfo>()) 119 MachineRegisterInfo(*TM.getRegisterInfo()); 120 else 121 RegInfo = 0; 122 MFInfo = 0; 123 FrameInfo = new (Allocator.Allocate<MachineFrameInfo>()) 124 MachineFrameInfo(*TM.getFrameInfo()); 125 ConstantPool = new (Allocator.Allocate<MachineConstantPool>()) 126 MachineConstantPool(TM.getTargetData()); 127 128 // Set up jump table. 129 const TargetData &TD = *TM.getTargetData(); 130 bool IsPic = TM.getRelocationModel() == Reloc::PIC_; 131 unsigned EntrySize = IsPic ? 4 : TD.getPointerSize(); 132 unsigned TyAlignment = IsPic ? TD.getABITypeAlignment(Type::Int32Ty) 133 : TD.getPointerABIAlignment(); 134 JumpTableInfo = new (Allocator.Allocate<MachineJumpTableInfo>()) 135 MachineJumpTableInfo(EntrySize, TyAlignment); 136} 137 138MachineFunction::~MachineFunction() { 139 BasicBlocks.clear(); 140 InstructionRecycler.clear(Allocator); 141 BasicBlockRecycler.clear(Allocator); 142 if (RegInfo) { 143 RegInfo->~MachineRegisterInfo(); 144 Allocator.Deallocate(RegInfo); 145 } 146 if (MFInfo) { 147 MFInfo->~MachineFunctionInfo(); 148 Allocator.Deallocate(MFInfo); 149 } 150 FrameInfo->~MachineFrameInfo(); Allocator.Deallocate(FrameInfo); 151 ConstantPool->~MachineConstantPool(); Allocator.Deallocate(ConstantPool); 152 JumpTableInfo->~MachineJumpTableInfo(); Allocator.Deallocate(JumpTableInfo); 153} 154 155 156/// RenumberBlocks - This discards all of the MachineBasicBlock numbers and 157/// recomputes them. This guarantees that the MBB numbers are sequential, 158/// dense, and match the ordering of the blocks within the function. If a 159/// specific MachineBasicBlock is specified, only that block and those after 160/// it are renumbered. 161void MachineFunction::RenumberBlocks(MachineBasicBlock *MBB) { 162 if (empty()) { MBBNumbering.clear(); return; } 163 MachineFunction::iterator MBBI, E = end(); 164 if (MBB == 0) 165 MBBI = begin(); 166 else 167 MBBI = MBB; 168 169 // Figure out the block number this should have. 170 unsigned BlockNo = 0; 171 if (MBBI != begin()) 172 BlockNo = prior(MBBI)->getNumber()+1; 173 174 for (; MBBI != E; ++MBBI, ++BlockNo) { 175 if (MBBI->getNumber() != (int)BlockNo) { 176 // Remove use of the old number. 177 if (MBBI->getNumber() != -1) { 178 assert(MBBNumbering[MBBI->getNumber()] == &*MBBI && 179 "MBB number mismatch!"); 180 MBBNumbering[MBBI->getNumber()] = 0; 181 } 182 183 // If BlockNo is already taken, set that block's number to -1. 184 if (MBBNumbering[BlockNo]) 185 MBBNumbering[BlockNo]->setNumber(-1); 186 187 MBBNumbering[BlockNo] = MBBI; 188 MBBI->setNumber(BlockNo); 189 } 190 } 191 192 // Okay, all the blocks are renumbered. If we have compactified the block 193 // numbering, shrink MBBNumbering now. 194 assert(BlockNo <= MBBNumbering.size() && "Mismatch!"); 195 MBBNumbering.resize(BlockNo); 196} 197 198/// CreateMachineInstr - Allocate a new MachineInstr. Use this instead 199/// of `new MachineInstr'. 200/// 201MachineInstr * 202MachineFunction::CreateMachineInstr(const TargetInstrDesc &TID, 203 DebugLoc DL, bool NoImp) { 204 return new (InstructionRecycler.Allocate<MachineInstr>(Allocator)) 205 MachineInstr(TID, DL, NoImp); 206} 207 208/// CloneMachineInstr - Create a new MachineInstr which is a copy of the 209/// 'Orig' instruction, identical in all ways except the the instruction 210/// has no parent, prev, or next. 211/// 212MachineInstr * 213MachineFunction::CloneMachineInstr(const MachineInstr *Orig) { 214 return new (InstructionRecycler.Allocate<MachineInstr>(Allocator)) 215 MachineInstr(*this, *Orig); 216} 217 218/// DeleteMachineInstr - Delete the given MachineInstr. 219/// 220void 221MachineFunction::DeleteMachineInstr(MachineInstr *MI) { 222 // Clear the instructions memoperands. This must be done manually because 223 // the instruction's parent pointer is now null, so it can't properly 224 // deallocate them on its own. 225 MI->clearMemOperands(*this); 226 227 MI->~MachineInstr(); 228 InstructionRecycler.Deallocate(Allocator, MI); 229} 230 231/// CreateMachineBasicBlock - Allocate a new MachineBasicBlock. Use this 232/// instead of `new MachineBasicBlock'. 233/// 234MachineBasicBlock * 235MachineFunction::CreateMachineBasicBlock(const BasicBlock *bb) { 236 return new (BasicBlockRecycler.Allocate<MachineBasicBlock>(Allocator)) 237 MachineBasicBlock(*this, bb); 238} 239 240/// DeleteMachineBasicBlock - Delete the given MachineBasicBlock. 241/// 242void 243MachineFunction::DeleteMachineBasicBlock(MachineBasicBlock *MBB) { 244 assert(MBB->getParent() == this && "MBB parent mismatch!"); 245 MBB->~MachineBasicBlock(); 246 BasicBlockRecycler.Deallocate(Allocator, MBB); 247} 248 249void MachineFunction::dump() const { 250 print(*cerr.stream()); 251} 252 253void MachineFunction::print(std::ostream &OS) const { 254 OS << "# Machine code for " << Fn->getName () << "():\n"; 255 256 // Print Frame Information 257 FrameInfo->print(*this, OS); 258 259 // Print JumpTable Information 260 JumpTableInfo->print(OS); 261 262 // Print Constant Pool 263 { 264 raw_os_ostream OSS(OS); 265 ConstantPool->print(OSS); 266 } 267 268 const TargetRegisterInfo *TRI = getTarget().getRegisterInfo(); 269 270 if (RegInfo && !RegInfo->livein_empty()) { 271 OS << "Live Ins:"; 272 for (MachineRegisterInfo::livein_iterator 273 I = RegInfo->livein_begin(), E = RegInfo->livein_end(); I != E; ++I) { 274 if (TRI) 275 OS << " " << TRI->getName(I->first); 276 else 277 OS << " Reg #" << I->first; 278 279 if (I->second) 280 OS << " in VR#" << I->second << " "; 281 } 282 OS << "\n"; 283 } 284 if (RegInfo && !RegInfo->liveout_empty()) { 285 OS << "Live Outs:"; 286 for (MachineRegisterInfo::liveout_iterator 287 I = RegInfo->liveout_begin(), E = RegInfo->liveout_end(); I != E; ++I) 288 if (TRI) 289 OS << " " << TRI->getName(*I); 290 else 291 OS << " Reg #" << *I; 292 OS << "\n"; 293 } 294 295 for (const_iterator BB = begin(); BB != end(); ++BB) 296 BB->print(OS); 297 298 OS << "\n# End machine code for " << Fn->getName () << "().\n\n"; 299} 300 301namespace llvm { 302 template<> 303 struct DOTGraphTraits<const MachineFunction*> : public DefaultDOTGraphTraits { 304 static std::string getGraphName(const MachineFunction *F) { 305 return "CFG for '" + F->getFunction()->getName() + "' function"; 306 } 307 308 static std::string getNodeLabel(const MachineBasicBlock *Node, 309 const MachineFunction *Graph, 310 bool ShortNames) { 311 if (ShortNames && Node->getBasicBlock() && 312 !Node->getBasicBlock()->getName().empty()) 313 return Node->getBasicBlock()->getName() + ":"; 314 315 std::ostringstream Out; 316 if (ShortNames) { 317 Out << Node->getNumber() << ':'; 318 return Out.str(); 319 } 320 321 Node->print(Out); 322 323 std::string OutStr = Out.str(); 324 if (OutStr[0] == '\n') OutStr.erase(OutStr.begin()); 325 326 // Process string output to make it nicer... 327 for (unsigned i = 0; i != OutStr.length(); ++i) 328 if (OutStr[i] == '\n') { // Left justify 329 OutStr[i] = '\\'; 330 OutStr.insert(OutStr.begin()+i+1, 'l'); 331 } 332 return OutStr; 333 } 334 }; 335} 336 337void MachineFunction::viewCFG() const 338{ 339#ifndef NDEBUG 340 ViewGraph(this, "mf" + getFunction()->getName()); 341#else 342 cerr << "SelectionDAG::viewGraph is only available in debug builds on " 343 << "systems with Graphviz or gv!\n"; 344#endif // NDEBUG 345} 346 347void MachineFunction::viewCFGOnly() const 348{ 349#ifndef NDEBUG 350 ViewGraph(this, "mf" + getFunction()->getName(), true); 351#else 352 cerr << "SelectionDAG::viewGraph is only available in debug builds on " 353 << "systems with Graphviz or gv!\n"; 354#endif // NDEBUG 355} 356 357// The next two methods are used to construct and to retrieve 358// the MachineCodeForFunction object for the given function. 359// construct() -- Allocates and initializes for a given function and target 360// get() -- Returns a handle to the object. 361// This should not be called before "construct()" 362// for a given Function. 363// 364MachineFunction& 365MachineFunction::construct(const Function *Fn, const TargetMachine &Tar) 366{ 367 AnnotationID MF_AID = 368 AnnotationManager::getID("CodeGen::MachineCodeForFunction"); 369 assert(Fn->getAnnotation(MF_AID) == 0 && 370 "Object already exists for this function!"); 371 MachineFunction* mcInfo = new MachineFunction(Fn, Tar); 372 Fn->addAnnotation(mcInfo); 373 return *mcInfo; 374} 375 376void MachineFunction::destruct(const Function *Fn) { 377 AnnotationID MF_AID = 378 AnnotationManager::getID("CodeGen::MachineCodeForFunction"); 379 bool Deleted = Fn->deleteAnnotation(MF_AID); 380 assert(Deleted && "Machine code did not exist for function!"); 381 Deleted = Deleted; // silence warning when no assertions. 382} 383 384MachineFunction& MachineFunction::get(const Function *F) 385{ 386 AnnotationID MF_AID = 387 AnnotationManager::getID("CodeGen::MachineCodeForFunction"); 388 MachineFunction *mc = (MachineFunction*)F->getAnnotation(MF_AID); 389 assert(mc && "Call construct() method first to allocate the object"); 390 return *mc; 391} 392 393/// addLiveIn - Add the specified physical register as a live-in value and 394/// create a corresponding virtual register for it. 395unsigned MachineFunction::addLiveIn(unsigned PReg, 396 const TargetRegisterClass *RC) { 397 assert(RC->contains(PReg) && "Not the correct regclass!"); 398 unsigned VReg = getRegInfo().createVirtualRegister(RC); 399 getRegInfo().addLiveIn(PReg, VReg); 400 return VReg; 401} 402 403/// getOrCreateDebugLocID - Look up the DebugLocTuple index with the given 404/// source file, line, and column. If none currently exists, create a new 405/// DebugLocTuple, and insert it into the DebugIdMap. 406unsigned MachineFunction::getOrCreateDebugLocID(GlobalVariable *CompileUnit, 407 unsigned Line, unsigned Col) { 408 DebugLocTuple Tuple(CompileUnit, Line, Col); 409 DenseMap<DebugLocTuple, unsigned>::iterator II 410 = DebugLocInfo.DebugIdMap.find(Tuple); 411 if (II != DebugLocInfo.DebugIdMap.end()) 412 return II->second; 413 // Add a new tuple. 414 unsigned Id = DebugLocInfo.DebugLocations.size(); 415 DebugLocInfo.DebugLocations.push_back(Tuple); 416 DebugLocInfo.DebugIdMap[Tuple] = Id; 417 return Id; 418} 419 420/// getDebugLocTuple - Get the DebugLocTuple for a given DebugLoc object. 421DebugLocTuple MachineFunction::getDebugLocTuple(DebugLoc DL) const { 422 unsigned Idx = DL.getIndex(); 423 assert(Idx < DebugLocInfo.DebugLocations.size() && 424 "Invalid index into debug locations!"); 425 return DebugLocInfo.DebugLocations[Idx]; 426} 427 428//===----------------------------------------------------------------------===// 429// MachineFrameInfo implementation 430//===----------------------------------------------------------------------===// 431 432/// CreateFixedObject - Create a new object at a fixed location on the stack. 433/// All fixed objects should be created before other objects are created for 434/// efficiency. By default, fixed objects are immutable. This returns an 435/// index with a negative value. 436/// 437int MachineFrameInfo::CreateFixedObject(uint64_t Size, int64_t SPOffset, 438 bool Immutable) { 439 assert(Size != 0 && "Cannot allocate zero size fixed stack objects!"); 440 Objects.insert(Objects.begin(), StackObject(Size, 1, SPOffset, Immutable)); 441 return -++NumFixedObjects; 442} 443 444 445void MachineFrameInfo::print(const MachineFunction &MF, std::ostream &OS) const{ 446 const TargetFrameInfo *FI = MF.getTarget().getFrameInfo(); 447 int ValOffset = (FI ? FI->getOffsetOfLocalArea() : 0); 448 449 for (unsigned i = 0, e = Objects.size(); i != e; ++i) { 450 const StackObject &SO = Objects[i]; 451 OS << " <fi#" << (int)(i-NumFixedObjects) << ">: "; 452 if (SO.Size == ~0ULL) { 453 OS << "dead\n"; 454 continue; 455 } 456 if (SO.Size == 0) 457 OS << "variable sized"; 458 else 459 OS << "size is " << SO.Size << " byte" << (SO.Size != 1 ? "s," : ","); 460 OS << " alignment is " << SO.Alignment << " byte" 461 << (SO.Alignment != 1 ? "s," : ","); 462 463 if (i < NumFixedObjects) 464 OS << " fixed"; 465 if (i < NumFixedObjects || SO.SPOffset != -1) { 466 int64_t Off = SO.SPOffset - ValOffset; 467 OS << " at location [SP"; 468 if (Off > 0) 469 OS << "+" << Off; 470 else if (Off < 0) 471 OS << Off; 472 OS << "]"; 473 } 474 OS << "\n"; 475 } 476 477 if (HasVarSizedObjects) 478 OS << " Stack frame contains variable sized objects\n"; 479} 480 481void MachineFrameInfo::dump(const MachineFunction &MF) const { 482 print(MF, *cerr.stream()); 483} 484 485 486//===----------------------------------------------------------------------===// 487// MachineJumpTableInfo implementation 488//===----------------------------------------------------------------------===// 489 490/// getJumpTableIndex - Create a new jump table entry in the jump table info 491/// or return an existing one. 492/// 493unsigned MachineJumpTableInfo::getJumpTableIndex( 494 const std::vector<MachineBasicBlock*> &DestBBs) { 495 assert(!DestBBs.empty() && "Cannot create an empty jump table!"); 496 for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) 497 if (JumpTables[i].MBBs == DestBBs) 498 return i; 499 500 JumpTables.push_back(MachineJumpTableEntry(DestBBs)); 501 return JumpTables.size()-1; 502} 503 504/// ReplaceMBBInJumpTables - If Old is the target of any jump tables, update 505/// the jump tables to branch to New instead. 506bool 507MachineJumpTableInfo::ReplaceMBBInJumpTables(MachineBasicBlock *Old, 508 MachineBasicBlock *New) { 509 assert(Old != New && "Not making a change?"); 510 bool MadeChange = false; 511 for (size_t i = 0, e = JumpTables.size(); i != e; ++i) { 512 MachineJumpTableEntry &JTE = JumpTables[i]; 513 for (size_t j = 0, e = JTE.MBBs.size(); j != e; ++j) 514 if (JTE.MBBs[j] == Old) { 515 JTE.MBBs[j] = New; 516 MadeChange = true; 517 } 518 } 519 return MadeChange; 520} 521 522void MachineJumpTableInfo::print(std::ostream &OS) const { 523 // FIXME: this is lame, maybe we could print out the MBB numbers or something 524 // like {1, 2, 4, 5, 3, 0} 525 for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) { 526 OS << " <jt#" << i << "> has " << JumpTables[i].MBBs.size() 527 << " entries\n"; 528 } 529} 530 531void MachineJumpTableInfo::dump() const { print(*cerr.stream()); } 532 533 534//===----------------------------------------------------------------------===// 535// MachineConstantPool implementation 536//===----------------------------------------------------------------------===// 537 538const Type *MachineConstantPoolEntry::getType() const { 539 if (isMachineConstantPoolEntry()) 540 return Val.MachineCPVal->getType(); 541 return Val.ConstVal->getType(); 542} 543 544MachineConstantPool::~MachineConstantPool() { 545 for (unsigned i = 0, e = Constants.size(); i != e; ++i) 546 if (Constants[i].isMachineConstantPoolEntry()) 547 delete Constants[i].Val.MachineCPVal; 548} 549 550/// getConstantPoolIndex - Create a new entry in the constant pool or return 551/// an existing one. User must specify the log2 of the minimum required 552/// alignment for the object. 553/// 554unsigned MachineConstantPool::getConstantPoolIndex(Constant *C, 555 unsigned Alignment) { 556 assert(Alignment && "Alignment must be specified!"); 557 if (Alignment > PoolAlignment) PoolAlignment = Alignment; 558 559 // Check to see if we already have this constant. 560 // 561 // FIXME, this could be made much more efficient for large constant pools. 562 for (unsigned i = 0, e = Constants.size(); i != e; ++i) 563 if (Constants[i].Val.ConstVal == C && 564 (Constants[i].getAlignment() & (Alignment - 1)) == 0) 565 return i; 566 567 Constants.push_back(MachineConstantPoolEntry(C, Alignment)); 568 return Constants.size()-1; 569} 570 571unsigned MachineConstantPool::getConstantPoolIndex(MachineConstantPoolValue *V, 572 unsigned Alignment) { 573 assert(Alignment && "Alignment must be specified!"); 574 if (Alignment > PoolAlignment) PoolAlignment = Alignment; 575 576 // Check to see if we already have this constant. 577 // 578 // FIXME, this could be made much more efficient for large constant pools. 579 int Idx = V->getExistingMachineCPValue(this, Alignment); 580 if (Idx != -1) 581 return (unsigned)Idx; 582 583 Constants.push_back(MachineConstantPoolEntry(V, Alignment)); 584 return Constants.size()-1; 585} 586 587void MachineConstantPool::print(raw_ostream &OS) const { 588 for (unsigned i = 0, e = Constants.size(); i != e; ++i) { 589 OS << " <cp#" << i << "> is"; 590 if (Constants[i].isMachineConstantPoolEntry()) 591 Constants[i].Val.MachineCPVal->print(OS); 592 else 593 OS << *(Value*)Constants[i].Val.ConstVal; 594 OS << " , alignment=" << Constants[i].getAlignment(); 595 OS << "\n"; 596 } 597} 598 599void MachineConstantPool::dump() const { print(errs()); } 600