MachineFunction.cpp revision d472ad7c7cb9378367bdc105dd208f80c7cd5998
1//===-- MachineFunction.cpp -----------------------------------------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file was developed by the LLVM research group and is distributed under 6// the University of Illinois Open Source 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/CodeGen/MachineFunctionPass.h" 17#include "llvm/CodeGen/MachineInstr.h" 18#include "llvm/CodeGen/SSARegMap.h" 19#include "llvm/CodeGen/MachineFrameInfo.h" 20#include "llvm/CodeGen/MachineConstantPool.h" 21#include "llvm/CodeGen/MachineJumpTableInfo.h" 22#include "llvm/CodeGen/Passes.h" 23#include "llvm/Target/TargetData.h" 24#include "llvm/Target/TargetLowering.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/LeakDetector.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 std::ostream *OS; 47 const std::string Banner; 48 49 Printer (std::ostream *_OS, const std::string &_Banner) : 50 OS (_OS), Banner (_Banner) { } 51 52 const char *getPassName() const { return "MachineFunction Printer"; } 53 54 virtual void getAnalysisUsage(AnalysisUsage &AU) const { 55 AU.setPreservesAll(); 56 } 57 58 bool runOnMachineFunction(MachineFunction &MF) { 59 (*OS) << Banner; 60 MF.print (*OS); 61 return false; 62 } 63 }; 64} 65 66/// Returns a newly-created MachineFunction Printer pass. The default output 67/// stream is std::cerr; the default banner is empty. 68/// 69FunctionPass *llvm::createMachineFunctionPrinterPass(std::ostream *OS, 70 const std::string &Banner){ 71 return new Printer(OS, Banner); 72} 73 74namespace { 75 struct VISIBILITY_HIDDEN Deleter : public MachineFunctionPass { 76 const char *getPassName() const { return "Machine Code Deleter"; } 77 78 bool runOnMachineFunction(MachineFunction &MF) { 79 // Delete the annotation from the function now. 80 MachineFunction::destruct(MF.getFunction()); 81 return true; 82 } 83 }; 84} 85 86/// MachineCodeDeletion Pass - This pass deletes all of the machine code for 87/// the current function, which should happen after the function has been 88/// emitted to a .s file or to memory. 89FunctionPass *llvm::createMachineCodeDeleter() { 90 return new Deleter(); 91} 92 93 94 95//===---------------------------------------------------------------------===// 96// MachineFunction implementation 97//===---------------------------------------------------------------------===// 98 99MachineBasicBlock* ilist_traits<MachineBasicBlock>::createSentinel() { 100 MachineBasicBlock* dummy = new MachineBasicBlock(); 101 LeakDetector::removeGarbageObject(dummy); 102 return dummy; 103} 104 105void ilist_traits<MachineBasicBlock>::transferNodesFromList( 106 iplist<MachineBasicBlock, ilist_traits<MachineBasicBlock> >& toList, 107 ilist_iterator<MachineBasicBlock> first, 108 ilist_iterator<MachineBasicBlock> last) { 109 if (Parent != toList.Parent) 110 for (; first != last; ++first) 111 first->Parent = toList.Parent; 112} 113 114MachineFunction::MachineFunction(const Function *F, 115 const TargetMachine &TM) 116 : Annotation(MF_AID), Fn(F), Target(TM), UsedPhysRegs(0) { 117 SSARegMapping = new SSARegMap(); 118 MFInfo = 0; 119 FrameInfo = new MachineFrameInfo(); 120 ConstantPool = new MachineConstantPool(TM.getTargetData()); 121 122 // Set up jump table. 123 const TargetData &TD = *TM.getTargetData(); 124 bool IsPic = TM.getRelocationModel() == Reloc::PIC_; 125 unsigned EntrySize = IsPic ? 4 : TD.getPointerSize(); 126 unsigned Alignment = IsPic ? TD.getIntAlignment() : TD.getPointerAlignment(); 127 JumpTableInfo = new MachineJumpTableInfo(EntrySize, Alignment); 128 129 BasicBlocks.Parent = this; 130} 131 132MachineFunction::~MachineFunction() { 133 BasicBlocks.clear(); 134 delete SSARegMapping; 135 delete MFInfo; 136 delete FrameInfo; 137 delete ConstantPool; 138 delete JumpTableInfo; 139 delete[] UsedPhysRegs; 140} 141 142 143/// RenumberBlocks - This discards all of the MachineBasicBlock numbers and 144/// recomputes them. This guarantees that the MBB numbers are sequential, 145/// dense, and match the ordering of the blocks within the function. If a 146/// specific MachineBasicBlock is specified, only that block and those after 147/// it are renumbered. 148void MachineFunction::RenumberBlocks(MachineBasicBlock *MBB) { 149 if (empty()) { MBBNumbering.clear(); return; } 150 MachineFunction::iterator MBBI, E = end(); 151 if (MBB == 0) 152 MBBI = begin(); 153 else 154 MBBI = MBB; 155 156 // Figure out the block number this should have. 157 unsigned BlockNo = 0; 158 if (MBBI != begin()) 159 BlockNo = prior(MBBI)->getNumber()+1; 160 161 for (; MBBI != E; ++MBBI, ++BlockNo) { 162 if (MBBI->getNumber() != (int)BlockNo) { 163 // Remove use of the old number. 164 if (MBBI->getNumber() != -1) { 165 assert(MBBNumbering[MBBI->getNumber()] == &*MBBI && 166 "MBB number mismatch!"); 167 MBBNumbering[MBBI->getNumber()] = 0; 168 } 169 170 // If BlockNo is already taken, set that block's number to -1. 171 if (MBBNumbering[BlockNo]) 172 MBBNumbering[BlockNo]->setNumber(-1); 173 174 MBBNumbering[BlockNo] = MBBI; 175 MBBI->setNumber(BlockNo); 176 } 177 } 178 179 // Okay, all the blocks are renumbered. If we have compactified the block 180 // numbering, shrink MBBNumbering now. 181 assert(BlockNo <= MBBNumbering.size() && "Mismatch!"); 182 MBBNumbering.resize(BlockNo); 183} 184 185 186void MachineFunction::dump() const { print(*cerr.stream()); } 187 188void MachineFunction::print(std::ostream &OS) const { 189 OS << "# Machine code for " << Fn->getName () << "():\n"; 190 191 // Print Frame Information 192 getFrameInfo()->print(*this, OS); 193 194 // Print JumpTable Information 195 getJumpTableInfo()->print(OS); 196 197 // Print Constant Pool 198 getConstantPool()->print(OS); 199 200 const MRegisterInfo *MRI = getTarget().getRegisterInfo(); 201 202 if (livein_begin() != livein_end()) { 203 OS << "Live Ins:"; 204 for (livein_iterator I = livein_begin(), E = livein_end(); I != E; ++I) { 205 if (MRI) 206 OS << " " << MRI->getName(I->first); 207 else 208 OS << " Reg #" << I->first; 209 210 if (I->second) 211 OS << " in VR#" << I->second << " "; 212 } 213 OS << "\n"; 214 } 215 if (liveout_begin() != liveout_end()) { 216 OS << "Live Outs:"; 217 for (liveout_iterator I = liveout_begin(), E = liveout_end(); I != E; ++I) 218 if (MRI) 219 OS << " " << MRI->getName(*I); 220 else 221 OS << " Reg #" << *I; 222 OS << "\n"; 223 } 224 225 for (const_iterator BB = begin(); BB != end(); ++BB) 226 BB->print(OS); 227 228 OS << "\n# End machine code for " << Fn->getName () << "().\n\n"; 229} 230 231/// CFGOnly flag - This is used to control whether or not the CFG graph printer 232/// prints out the contents of basic blocks or not. This is acceptable because 233/// this code is only really used for debugging purposes. 234/// 235static bool CFGOnly = false; 236 237namespace llvm { 238 template<> 239 struct DOTGraphTraits<const MachineFunction*> : public DefaultDOTGraphTraits { 240 static std::string getGraphName(const MachineFunction *F) { 241 return "CFG for '" + F->getFunction()->getName() + "' function"; 242 } 243 244 static std::string getNodeLabel(const MachineBasicBlock *Node, 245 const MachineFunction *Graph) { 246 if (CFGOnly && Node->getBasicBlock() && 247 !Node->getBasicBlock()->getName().empty()) 248 return Node->getBasicBlock()->getName() + ":"; 249 250 std::ostringstream Out; 251 if (CFGOnly) { 252 Out << Node->getNumber() << ':'; 253 return Out.str(); 254 } 255 256 Node->print(Out); 257 258 std::string OutStr = Out.str(); 259 if (OutStr[0] == '\n') OutStr.erase(OutStr.begin()); 260 261 // Process string output to make it nicer... 262 for (unsigned i = 0; i != OutStr.length(); ++i) 263 if (OutStr[i] == '\n') { // Left justify 264 OutStr[i] = '\\'; 265 OutStr.insert(OutStr.begin()+i+1, 'l'); 266 } 267 return OutStr; 268 } 269 }; 270} 271 272void MachineFunction::viewCFG() const 273{ 274#ifndef NDEBUG 275 ViewGraph(this, "mf" + getFunction()->getName()); 276#else 277 cerr << "SelectionDAG::viewGraph is only available in debug builds on " 278 << "systems with Graphviz or gv!\n"; 279#endif // NDEBUG 280} 281 282void MachineFunction::viewCFGOnly() const 283{ 284 CFGOnly = true; 285 viewCFG(); 286 CFGOnly = false; 287} 288 289// The next two methods are used to construct and to retrieve 290// the MachineCodeForFunction object for the given function. 291// construct() -- Allocates and initializes for a given function and target 292// get() -- Returns a handle to the object. 293// This should not be called before "construct()" 294// for a given Function. 295// 296MachineFunction& 297MachineFunction::construct(const Function *Fn, const TargetMachine &Tar) 298{ 299 assert(Fn->getAnnotation(MF_AID) == 0 && 300 "Object already exists for this function!"); 301 MachineFunction* mcInfo = new MachineFunction(Fn, Tar); 302 Fn->addAnnotation(mcInfo); 303 return *mcInfo; 304} 305 306void MachineFunction::destruct(const Function *Fn) { 307 bool Deleted = Fn->deleteAnnotation(MF_AID); 308 assert(Deleted && "Machine code did not exist for function!"); 309} 310 311MachineFunction& MachineFunction::get(const Function *F) 312{ 313 MachineFunction *mc = (MachineFunction*)F->getAnnotation(MF_AID); 314 assert(mc && "Call construct() method first to allocate the object"); 315 return *mc; 316} 317 318void MachineFunction::clearSSARegMap() { 319 delete SSARegMapping; 320 SSARegMapping = 0; 321} 322 323//===----------------------------------------------------------------------===// 324// MachineFrameInfo implementation 325//===----------------------------------------------------------------------===// 326 327void MachineFrameInfo::print(const MachineFunction &MF, std::ostream &OS) const{ 328 int ValOffset = MF.getTarget().getFrameInfo()->getOffsetOfLocalArea(); 329 330 for (unsigned i = 0, e = Objects.size(); i != e; ++i) { 331 const StackObject &SO = Objects[i]; 332 OS << " <fi #" << (int)(i-NumFixedObjects) << ">: "; 333 if (SO.Size == 0) 334 OS << "variable sized"; 335 else 336 OS << "size is " << SO.Size << " byte" << (SO.Size != 1 ? "s," : ","); 337 OS << " alignment is " << SO.Alignment << " byte" 338 << (SO.Alignment != 1 ? "s," : ","); 339 340 if (i < NumFixedObjects) 341 OS << " fixed"; 342 if (i < NumFixedObjects || SO.SPOffset != -1) { 343 int Off = SO.SPOffset - ValOffset; 344 OS << " at location [SP"; 345 if (Off > 0) 346 OS << "+" << Off; 347 else if (Off < 0) 348 OS << Off; 349 OS << "]"; 350 } 351 OS << "\n"; 352 } 353 354 if (HasVarSizedObjects) 355 OS << " Stack frame contains variable sized objects\n"; 356} 357 358void MachineFrameInfo::dump(const MachineFunction &MF) const { 359 print(MF, *cerr.stream()); 360} 361 362 363//===----------------------------------------------------------------------===// 364// MachineJumpTableInfo implementation 365//===----------------------------------------------------------------------===// 366 367/// getJumpTableIndex - Create a new jump table entry in the jump table info 368/// or return an existing one. 369/// 370unsigned MachineJumpTableInfo::getJumpTableIndex( 371 const std::vector<MachineBasicBlock*> &DestBBs) { 372 assert(!DestBBs.empty() && "Cannot create an empty jump table!"); 373 for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) 374 if (JumpTables[i].MBBs == DestBBs) 375 return i; 376 377 JumpTables.push_back(MachineJumpTableEntry(DestBBs)); 378 return JumpTables.size()-1; 379} 380 381 382void MachineJumpTableInfo::print(std::ostream &OS) const { 383 // FIXME: this is lame, maybe we could print out the MBB numbers or something 384 // like {1, 2, 4, 5, 3, 0} 385 for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) { 386 OS << " <jt #" << i << "> has " << JumpTables[i].MBBs.size() 387 << " entries\n"; 388 } 389} 390 391void MachineJumpTableInfo::dump() const { print(*cerr.stream()); } 392 393 394//===----------------------------------------------------------------------===// 395// MachineConstantPool implementation 396//===----------------------------------------------------------------------===// 397 398const Type *MachineConstantPoolEntry::getType() const { 399 if (isMachineConstantPoolEntry()) 400 return Val.MachineCPVal->getType(); 401 return Val.ConstVal->getType(); 402} 403 404MachineConstantPool::~MachineConstantPool() { 405 for (unsigned i = 0, e = Constants.size(); i != e; ++i) 406 if (Constants[i].isMachineConstantPoolEntry()) 407 delete Constants[i].Val.MachineCPVal; 408} 409 410/// getConstantPoolIndex - Create a new entry in the constant pool or return 411/// an existing one. User must specify an alignment in bytes for the object. 412/// 413unsigned MachineConstantPool::getConstantPoolIndex(Constant *C, 414 unsigned Alignment) { 415 assert(Alignment && "Alignment must be specified!"); 416 if (Alignment > PoolAlignment) PoolAlignment = Alignment; 417 418 // Check to see if we already have this constant. 419 // 420 // FIXME, this could be made much more efficient for large constant pools. 421 unsigned AlignMask = (1 << Alignment)-1; 422 for (unsigned i = 0, e = Constants.size(); i != e; ++i) 423 if (Constants[i].Val.ConstVal == C && (Constants[i].Offset & AlignMask)== 0) 424 return i; 425 426 unsigned Offset = 0; 427 if (!Constants.empty()) { 428 Offset = Constants.back().getOffset(); 429 Offset += TD->getTypeSize(Constants.back().getType()); 430 Offset = (Offset+AlignMask)&~AlignMask; 431 } 432 433 Constants.push_back(MachineConstantPoolEntry(C, Offset)); 434 return Constants.size()-1; 435} 436 437unsigned MachineConstantPool::getConstantPoolIndex(MachineConstantPoolValue *V, 438 unsigned Alignment) { 439 assert(Alignment && "Alignment must be specified!"); 440 if (Alignment > PoolAlignment) PoolAlignment = Alignment; 441 442 // Check to see if we already have this constant. 443 // 444 // FIXME, this could be made much more efficient for large constant pools. 445 unsigned AlignMask = (1 << Alignment)-1; 446 int Idx = V->getExistingMachineCPValue(this, Alignment); 447 if (Idx != -1) 448 return (unsigned)Idx; 449 450 unsigned Offset = 0; 451 if (!Constants.empty()) { 452 Offset = Constants.back().getOffset(); 453 Offset += TD->getTypeSize(Constants.back().getType()); 454 Offset = (Offset+AlignMask)&~AlignMask; 455 } 456 457 Constants.push_back(MachineConstantPoolEntry(V, Offset)); 458 return Constants.size()-1; 459} 460 461 462void MachineConstantPool::print(std::ostream &OS) const { 463 for (unsigned i = 0, e = Constants.size(); i != e; ++i) { 464 OS << " <cp #" << i << "> is"; 465 if (Constants[i].isMachineConstantPoolEntry()) 466 Constants[i].Val.MachineCPVal->print(OS); 467 else 468 OS << *(Value*)Constants[i].Val.ConstVal; 469 OS << " , offset=" << Constants[i].getOffset(); 470 OS << "\n"; 471 } 472} 473 474void MachineConstantPool::dump() const { print(*cerr.stream()); } 475