MachineFunction.cpp revision ceb4d1aecb9deffe59b3dcdc9a783ffde8477be9
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 38static AnnotationID MF_AID( 39 AnnotationManager::getID("CodeGen::MachineCodeForFunction")); 40 41// Out of line virtual function to home classes. 42void MachineFunctionPass::virtfn() {} 43 44namespace { 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/// 72FunctionPass *llvm::createMachineFunctionPrinterPass(std::ostream *OS, 73 const std::string &Banner){ 74 return new Printer(OS, Banner); 75} 76 77namespace { 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. 96FunctionPass *llvm::createMachineCodeDeleter() { 97 return new Deleter(); 98} 99 100 101 102//===---------------------------------------------------------------------===// 103// MachineFunction implementation 104//===---------------------------------------------------------------------===// 105 106void ilist_traits<MachineBasicBlock>::deleteNode(MachineBasicBlock *MBB) { 107 MBB->getParent()->DeleteMachineBasicBlock(MBB); 108} 109 110MachineFunction::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 134MachineFunction::~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. 154void 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/// 194MachineInstr * 195MachineFunction::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/// 204MachineInstr * 205MachineFunction::CloneMachineInstr(const MachineInstr *Orig) { 206 return new (InstructionRecycler.Allocate<MachineInstr>(Allocator)) 207 MachineInstr(*this, *Orig); 208} 209 210/// DeleteMachineInstr - Delete the given MachineInstr. 211/// 212void 213MachineFunction::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/// 226MachineBasicBlock * 227MachineFunction::CreateMachineBasicBlock(const BasicBlock *bb) { 228 return new (BasicBlockRecycler.Allocate<MachineBasicBlock>(Allocator)) 229 MachineBasicBlock(*this, bb); 230} 231 232/// DeleteMachineBasicBlock - Delete the given MachineBasicBlock. 233/// 234void 235MachineFunction::DeleteMachineBasicBlock(MachineBasicBlock *MBB) { 236 assert(MBB->getParent() == this && "MBB parent mismatch!"); 237 MBB->~MachineBasicBlock(); 238 BasicBlockRecycler.Deallocate(Allocator, MBB); 239} 240 241void MachineFunction::dump() const { 242 print(*cerr.stream()); 243} 244 245void 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/// 297static bool CFGOnly = false; 298 299namespace 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 334void 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 344void 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// 358MachineFunction& 359MachineFunction::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 368void 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 374MachineFunction& 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//===----------------------------------------------------------------------===// 382// MachineFrameInfo implementation 383//===----------------------------------------------------------------------===// 384 385/// CreateFixedObject - Create a new object at a fixed location on the stack. 386/// All fixed objects should be created before other objects are created for 387/// efficiency. By default, fixed objects are immutable. This returns an 388/// index with a negative value. 389/// 390int MachineFrameInfo::CreateFixedObject(uint64_t Size, int64_t SPOffset, 391 bool Immutable) { 392 assert(Size != 0 && "Cannot allocate zero size fixed stack objects!"); 393 Objects.insert(Objects.begin(), StackObject(Size, 1, SPOffset, Immutable)); 394 return -++NumFixedObjects; 395} 396 397 398void MachineFrameInfo::print(const MachineFunction &MF, std::ostream &OS) const{ 399 const TargetFrameInfo *FI = MF.getTarget().getFrameInfo(); 400 int ValOffset = (FI ? FI->getOffsetOfLocalArea() : 0); 401 402 for (unsigned i = 0, e = Objects.size(); i != e; ++i) { 403 const StackObject &SO = Objects[i]; 404 OS << " <fi#" << (int)(i-NumFixedObjects) << ">: "; 405 if (SO.Size == ~0ULL) { 406 OS << "dead\n"; 407 continue; 408 } 409 if (SO.Size == 0) 410 OS << "variable sized"; 411 else 412 OS << "size is " << SO.Size << " byte" << (SO.Size != 1 ? "s," : ","); 413 OS << " alignment is " << SO.Alignment << " byte" 414 << (SO.Alignment != 1 ? "s," : ","); 415 416 if (i < NumFixedObjects) 417 OS << " fixed"; 418 if (i < NumFixedObjects || SO.SPOffset != -1) { 419 int64_t Off = SO.SPOffset - ValOffset; 420 OS << " at location [SP"; 421 if (Off > 0) 422 OS << "+" << Off; 423 else if (Off < 0) 424 OS << Off; 425 OS << "]"; 426 } 427 OS << "\n"; 428 } 429 430 if (HasVarSizedObjects) 431 OS << " Stack frame contains variable sized objects\n"; 432} 433 434void MachineFrameInfo::dump(const MachineFunction &MF) const { 435 print(MF, *cerr.stream()); 436} 437 438 439//===----------------------------------------------------------------------===// 440// MachineJumpTableInfo implementation 441//===----------------------------------------------------------------------===// 442 443/// getJumpTableIndex - Create a new jump table entry in the jump table info 444/// or return an existing one. 445/// 446unsigned MachineJumpTableInfo::getJumpTableIndex( 447 const std::vector<MachineBasicBlock*> &DestBBs) { 448 assert(!DestBBs.empty() && "Cannot create an empty jump table!"); 449 for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) 450 if (JumpTables[i].MBBs == DestBBs) 451 return i; 452 453 JumpTables.push_back(MachineJumpTableEntry(DestBBs)); 454 return JumpTables.size()-1; 455} 456 457 458void MachineJumpTableInfo::print(std::ostream &OS) const { 459 // FIXME: this is lame, maybe we could print out the MBB numbers or something 460 // like {1, 2, 4, 5, 3, 0} 461 for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) { 462 OS << " <jt#" << i << "> has " << JumpTables[i].MBBs.size() 463 << " entries\n"; 464 } 465} 466 467void MachineJumpTableInfo::dump() const { print(*cerr.stream()); } 468 469 470//===----------------------------------------------------------------------===// 471// MachineConstantPool implementation 472//===----------------------------------------------------------------------===// 473 474const Type *MachineConstantPoolEntry::getType() const { 475 if (isMachineConstantPoolEntry()) 476 return Val.MachineCPVal->getType(); 477 return Val.ConstVal->getType(); 478} 479 480MachineConstantPool::~MachineConstantPool() { 481 for (unsigned i = 0, e = Constants.size(); i != e; ++i) 482 if (Constants[i].isMachineConstantPoolEntry()) 483 delete Constants[i].Val.MachineCPVal; 484} 485 486/// getConstantPoolIndex - Create a new entry in the constant pool or return 487/// an existing one. User must specify the log2 of the minimum required 488/// alignment for the object. 489/// 490unsigned MachineConstantPool::getConstantPoolIndex(Constant *C, 491 unsigned Alignment) { 492 assert(Alignment && "Alignment must be specified!"); 493 if (Alignment > PoolAlignment) PoolAlignment = Alignment; 494 495 // Check to see if we already have this constant. 496 // 497 // FIXME, this could be made much more efficient for large constant pools. 498 unsigned AlignMask = (1 << Alignment)-1; 499 for (unsigned i = 0, e = Constants.size(); i != e; ++i) 500 if (Constants[i].Val.ConstVal == C && (Constants[i].Offset & AlignMask)== 0) 501 return i; 502 503 unsigned Offset = 0; 504 if (!Constants.empty()) { 505 Offset = Constants.back().getOffset(); 506 Offset += TD->getTypePaddedSize(Constants.back().getType()); 507 Offset = (Offset+AlignMask)&~AlignMask; 508 } 509 510 Constants.push_back(MachineConstantPoolEntry(C, Offset)); 511 return Constants.size()-1; 512} 513 514unsigned MachineConstantPool::getConstantPoolIndex(MachineConstantPoolValue *V, 515 unsigned Alignment) { 516 assert(Alignment && "Alignment must be specified!"); 517 if (Alignment > PoolAlignment) PoolAlignment = Alignment; 518 519 // Check to see if we already have this constant. 520 // 521 // FIXME, this could be made much more efficient for large constant pools. 522 unsigned AlignMask = (1 << Alignment)-1; 523 int Idx = V->getExistingMachineCPValue(this, Alignment); 524 if (Idx != -1) 525 return (unsigned)Idx; 526 527 unsigned Offset = 0; 528 if (!Constants.empty()) { 529 Offset = Constants.back().getOffset(); 530 Offset += TD->getTypePaddedSize(Constants.back().getType()); 531 Offset = (Offset+AlignMask)&~AlignMask; 532 } 533 534 Constants.push_back(MachineConstantPoolEntry(V, Offset)); 535 return Constants.size()-1; 536} 537 538void MachineConstantPool::print(raw_ostream &OS) const { 539 for (unsigned i = 0, e = Constants.size(); i != e; ++i) { 540 OS << " <cp#" << i << "> is"; 541 if (Constants[i].isMachineConstantPoolEntry()) 542 Constants[i].Val.MachineCPVal->print(OS); 543 else 544 OS << *(Value*)Constants[i].Val.ConstVal; 545 OS << " , offset=" << Constants[i].getOffset(); 546 OS << "\n"; 547 } 548} 549 550void MachineConstantPool::dump() const { print(errs()); errs().flush(); } 551