1 //===-- Module.cpp - Implement the Module class ---------------------------===// 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 // This file implements the Module class for the VMCore library. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #include "llvm/Module.h" 15 #include "llvm/InstrTypes.h" 16 #include "llvm/Constants.h" 17 #include "llvm/DerivedTypes.h" 18 #include "llvm/GVMaterializer.h" 19 #include "llvm/LLVMContext.h" 20 #include "llvm/ADT/DenseSet.h" 21 #include "llvm/ADT/SmallString.h" 22 #include "llvm/ADT/STLExtras.h" 23 #include "llvm/ADT/StringExtras.h" 24 #include "llvm/Support/LeakDetector.h" 25 #include "SymbolTableListTraitsImpl.h" 26 #include <algorithm> 27 #include <cstdarg> 28 #include <cstdlib> 29 using namespace llvm; 30 31 //===----------------------------------------------------------------------===// 32 // Methods to implement the globals and functions lists. 33 // 34 35 // Explicit instantiations of SymbolTableListTraits since some of the methods 36 // are not in the public header file. 37 template class llvm::SymbolTableListTraits<Function, Module>; 38 template class llvm::SymbolTableListTraits<GlobalVariable, Module>; 39 template class llvm::SymbolTableListTraits<GlobalAlias, Module>; 40 41 //===----------------------------------------------------------------------===// 42 // Primitive Module methods. 43 // 44 45 Module::Module(StringRef MID, LLVMContext& C) 46 : Context(C), Materializer(NULL), ModuleID(MID) { 47 ValSymTab = new ValueSymbolTable(); 48 NamedMDSymTab = new StringMap<NamedMDNode *>(); 49 Context.addModule(this); 50 } 51 52 Module::~Module() { 53 Context.removeModule(this); 54 dropAllReferences(); 55 GlobalList.clear(); 56 FunctionList.clear(); 57 AliasList.clear(); 58 LibraryList.clear(); 59 NamedMDList.clear(); 60 delete ValSymTab; 61 delete static_cast<StringMap<NamedMDNode *> *>(NamedMDSymTab); 62 } 63 64 /// Target endian information. 65 Module::Endianness Module::getEndianness() const { 66 StringRef temp = DataLayout; 67 Module::Endianness ret = AnyEndianness; 68 69 while (!temp.empty()) { 70 std::pair<StringRef, StringRef> P = getToken(temp, "-"); 71 72 StringRef token = P.first; 73 temp = P.second; 74 75 if (token[0] == 'e') { 76 ret = LittleEndian; 77 } else if (token[0] == 'E') { 78 ret = BigEndian; 79 } 80 } 81 82 return ret; 83 } 84 85 /// Target Pointer Size information. 86 Module::PointerSize Module::getPointerSize() const { 87 StringRef temp = DataLayout; 88 Module::PointerSize ret = AnyPointerSize; 89 90 while (!temp.empty()) { 91 std::pair<StringRef, StringRef> TmpP = getToken(temp, "-"); 92 temp = TmpP.second; 93 TmpP = getToken(TmpP.first, ":"); 94 StringRef token = TmpP.second, signalToken = TmpP.first; 95 96 if (signalToken[0] == 'p') { 97 int size = 0; 98 getToken(token, ":").first.getAsInteger(10, size); 99 if (size == 32) 100 ret = Pointer32; 101 else if (size == 64) 102 ret = Pointer64; 103 } 104 } 105 106 return ret; 107 } 108 109 /// getNamedValue - Return the first global value in the module with 110 /// the specified name, of arbitrary type. This method returns null 111 /// if a global with the specified name is not found. 112 GlobalValue *Module::getNamedValue(StringRef Name) const { 113 return cast_or_null<GlobalValue>(getValueSymbolTable().lookup(Name)); 114 } 115 116 /// getMDKindID - Return a unique non-zero ID for the specified metadata kind. 117 /// This ID is uniqued across modules in the current LLVMContext. 118 unsigned Module::getMDKindID(StringRef Name) const { 119 return Context.getMDKindID(Name); 120 } 121 122 /// getMDKindNames - Populate client supplied SmallVector with the name for 123 /// custom metadata IDs registered in this LLVMContext. ID #0 is not used, 124 /// so it is filled in as an empty string. 125 void Module::getMDKindNames(SmallVectorImpl<StringRef> &Result) const { 126 return Context.getMDKindNames(Result); 127 } 128 129 130 //===----------------------------------------------------------------------===// 131 // Methods for easy access to the functions in the module. 132 // 133 134 // getOrInsertFunction - Look up the specified function in the module symbol 135 // table. If it does not exist, add a prototype for the function and return 136 // it. This is nice because it allows most passes to get away with not handling 137 // the symbol table directly for this common task. 138 // 139 Constant *Module::getOrInsertFunction(StringRef Name, 140 FunctionType *Ty, 141 AttrListPtr AttributeList) { 142 // See if we have a definition for the specified function already. 143 GlobalValue *F = getNamedValue(Name); 144 if (F == 0) { 145 // Nope, add it 146 Function *New = Function::Create(Ty, GlobalVariable::ExternalLinkage, Name); 147 if (!New->isIntrinsic()) // Intrinsics get attrs set on construction 148 New->setAttributes(AttributeList); 149 FunctionList.push_back(New); 150 return New; // Return the new prototype. 151 } 152 153 // Okay, the function exists. Does it have externally visible linkage? 154 if (F->hasLocalLinkage()) { 155 // Clear the function's name. 156 F->setName(""); 157 // Retry, now there won't be a conflict. 158 Constant *NewF = getOrInsertFunction(Name, Ty); 159 F->setName(Name); 160 return NewF; 161 } 162 163 // If the function exists but has the wrong type, return a bitcast to the 164 // right type. 165 if (F->getType() != PointerType::getUnqual(Ty)) 166 return ConstantExpr::getBitCast(F, PointerType::getUnqual(Ty)); 167 168 // Otherwise, we just found the existing function or a prototype. 169 return F; 170 } 171 172 Constant *Module::getOrInsertTargetIntrinsic(StringRef Name, 173 FunctionType *Ty, 174 AttrListPtr AttributeList) { 175 // See if we have a definition for the specified function already. 176 GlobalValue *F = getNamedValue(Name); 177 if (F == 0) { 178 // Nope, add it 179 Function *New = Function::Create(Ty, GlobalVariable::ExternalLinkage, Name); 180 New->setAttributes(AttributeList); 181 FunctionList.push_back(New); 182 return New; // Return the new prototype. 183 } 184 185 // Otherwise, we just found the existing function or a prototype. 186 return F; 187 } 188 189 Constant *Module::getOrInsertFunction(StringRef Name, 190 FunctionType *Ty) { 191 AttrListPtr AttributeList = AttrListPtr::get((AttributeWithIndex *)0, 0); 192 return getOrInsertFunction(Name, Ty, AttributeList); 193 } 194 195 // getOrInsertFunction - Look up the specified function in the module symbol 196 // table. If it does not exist, add a prototype for the function and return it. 197 // This version of the method takes a null terminated list of function 198 // arguments, which makes it easier for clients to use. 199 // 200 Constant *Module::getOrInsertFunction(StringRef Name, 201 AttrListPtr AttributeList, 202 Type *RetTy, ...) { 203 va_list Args; 204 va_start(Args, RetTy); 205 206 // Build the list of argument types... 207 std::vector<Type*> ArgTys; 208 while (Type *ArgTy = va_arg(Args, Type*)) 209 ArgTys.push_back(ArgTy); 210 211 va_end(Args); 212 213 // Build the function type and chain to the other getOrInsertFunction... 214 return getOrInsertFunction(Name, 215 FunctionType::get(RetTy, ArgTys, false), 216 AttributeList); 217 } 218 219 Constant *Module::getOrInsertFunction(StringRef Name, 220 Type *RetTy, ...) { 221 va_list Args; 222 va_start(Args, RetTy); 223 224 // Build the list of argument types... 225 std::vector<Type*> ArgTys; 226 while (Type *ArgTy = va_arg(Args, Type*)) 227 ArgTys.push_back(ArgTy); 228 229 va_end(Args); 230 231 // Build the function type and chain to the other getOrInsertFunction... 232 return getOrInsertFunction(Name, 233 FunctionType::get(RetTy, ArgTys, false), 234 AttrListPtr::get((AttributeWithIndex *)0, 0)); 235 } 236 237 // getFunction - Look up the specified function in the module symbol table. 238 // If it does not exist, return null. 239 // 240 Function *Module::getFunction(StringRef Name) const { 241 return dyn_cast_or_null<Function>(getNamedValue(Name)); 242 } 243 244 //===----------------------------------------------------------------------===// 245 // Methods for easy access to the global variables in the module. 246 // 247 248 /// getGlobalVariable - Look up the specified global variable in the module 249 /// symbol table. If it does not exist, return null. The type argument 250 /// should be the underlying type of the global, i.e., it should not have 251 /// the top-level PointerType, which represents the address of the global. 252 /// If AllowLocal is set to true, this function will return types that 253 /// have an local. By default, these types are not returned. 254 /// 255 GlobalVariable *Module::getGlobalVariable(StringRef Name, 256 bool AllowLocal) const { 257 if (GlobalVariable *Result = 258 dyn_cast_or_null<GlobalVariable>(getNamedValue(Name))) 259 if (AllowLocal || !Result->hasLocalLinkage()) 260 return Result; 261 return 0; 262 } 263 264 /// getOrInsertGlobal - Look up the specified global in the module symbol table. 265 /// 1. If it does not exist, add a declaration of the global and return it. 266 /// 2. Else, the global exists but has the wrong type: return the function 267 /// with a constantexpr cast to the right type. 268 /// 3. Finally, if the existing global is the correct delclaration, return the 269 /// existing global. 270 Constant *Module::getOrInsertGlobal(StringRef Name, Type *Ty) { 271 // See if we have a definition for the specified global already. 272 GlobalVariable *GV = dyn_cast_or_null<GlobalVariable>(getNamedValue(Name)); 273 if (GV == 0) { 274 // Nope, add it 275 GlobalVariable *New = 276 new GlobalVariable(*this, Ty, false, GlobalVariable::ExternalLinkage, 277 0, Name); 278 return New; // Return the new declaration. 279 } 280 281 // If the variable exists but has the wrong type, return a bitcast to the 282 // right type. 283 if (GV->getType() != PointerType::getUnqual(Ty)) 284 return ConstantExpr::getBitCast(GV, PointerType::getUnqual(Ty)); 285 286 // Otherwise, we just found the existing function or a prototype. 287 return GV; 288 } 289 290 //===----------------------------------------------------------------------===// 291 // Methods for easy access to the global variables in the module. 292 // 293 294 // getNamedAlias - Look up the specified global in the module symbol table. 295 // If it does not exist, return null. 296 // 297 GlobalAlias *Module::getNamedAlias(StringRef Name) const { 298 return dyn_cast_or_null<GlobalAlias>(getNamedValue(Name)); 299 } 300 301 /// getNamedMetadata - Return the first NamedMDNode in the module with the 302 /// specified name. This method returns null if a NamedMDNode with the 303 /// specified name is not found. 304 NamedMDNode *Module::getNamedMetadata(const Twine &Name) const { 305 SmallString<256> NameData; 306 StringRef NameRef = Name.toStringRef(NameData); 307 return static_cast<StringMap<NamedMDNode*> *>(NamedMDSymTab)->lookup(NameRef); 308 } 309 310 /// getOrInsertNamedMetadata - Return the first named MDNode in the module 311 /// with the specified name. This method returns a new NamedMDNode if a 312 /// NamedMDNode with the specified name is not found. 313 NamedMDNode *Module::getOrInsertNamedMetadata(StringRef Name) { 314 NamedMDNode *&NMD = 315 (*static_cast<StringMap<NamedMDNode *> *>(NamedMDSymTab))[Name]; 316 if (!NMD) { 317 NMD = new NamedMDNode(Name); 318 NMD->setParent(this); 319 NamedMDList.push_back(NMD); 320 } 321 return NMD; 322 } 323 324 /// eraseNamedMetadata - Remove the given NamedMDNode from this module and 325 /// delete it. 326 void Module::eraseNamedMetadata(NamedMDNode *NMD) { 327 static_cast<StringMap<NamedMDNode *> *>(NamedMDSymTab)->erase(NMD->getName()); 328 NamedMDList.erase(NMD); 329 } 330 331 /// getModuleFlagsMetadata - Returns the module flags in the provided vector. 332 void Module:: 333 getModuleFlagsMetadata(SmallVectorImpl<ModuleFlagEntry> &Flags) const { 334 const NamedMDNode *ModFlags = getModuleFlagsMetadata(); 335 if (!ModFlags) return; 336 337 for (unsigned i = 0, e = ModFlags->getNumOperands(); i != e; ++i) { 338 MDNode *Flag = ModFlags->getOperand(i); 339 ConstantInt *Behavior = cast<ConstantInt>(Flag->getOperand(0)); 340 MDString *Key = cast<MDString>(Flag->getOperand(1)); 341 Value *Val = Flag->getOperand(2); 342 Flags.push_back(ModuleFlagEntry(ModFlagBehavior(Behavior->getZExtValue()), 343 Key, Val)); 344 } 345 } 346 347 /// getModuleFlagsMetadata - Returns the NamedMDNode in the module that 348 /// represents module-level flags. This method returns null if there are no 349 /// module-level flags. 350 NamedMDNode *Module::getModuleFlagsMetadata() const { 351 return getNamedMetadata("llvm.module.flags"); 352 } 353 354 /// getOrInsertModuleFlagsMetadata - Returns the NamedMDNode in the module that 355 /// represents module-level flags. If module-level flags aren't found, it 356 /// creates the named metadata that contains them. 357 NamedMDNode *Module::getOrInsertModuleFlagsMetadata() { 358 return getOrInsertNamedMetadata("llvm.module.flags"); 359 } 360 361 /// addModuleFlag - Add a module-level flag to the module-level flags 362 /// metadata. It will create the module-level flags named metadata if it doesn't 363 /// already exist. 364 void Module::addModuleFlag(ModFlagBehavior Behavior, StringRef Key, 365 Value *Val) { 366 Type *Int32Ty = Type::getInt32Ty(Context); 367 Value *Ops[3] = { 368 ConstantInt::get(Int32Ty, Behavior), MDString::get(Context, Key), Val 369 }; 370 getOrInsertModuleFlagsMetadata()->addOperand(MDNode::get(Context, Ops)); 371 } 372 void Module::addModuleFlag(ModFlagBehavior Behavior, StringRef Key, 373 uint32_t Val) { 374 Type *Int32Ty = Type::getInt32Ty(Context); 375 addModuleFlag(Behavior, Key, ConstantInt::get(Int32Ty, Val)); 376 } 377 void Module::addModuleFlag(MDNode *Node) { 378 assert(Node->getNumOperands() == 3 && 379 "Invalid number of operands for module flag!"); 380 assert(isa<ConstantInt>(Node->getOperand(0)) && 381 isa<MDString>(Node->getOperand(1)) && 382 "Invalid operand types for module flag!"); 383 getOrInsertModuleFlagsMetadata()->addOperand(Node); 384 } 385 386 //===----------------------------------------------------------------------===// 387 // Methods to control the materialization of GlobalValues in the Module. 388 // 389 void Module::setMaterializer(GVMaterializer *GVM) { 390 assert(!Materializer && 391 "Module already has a GVMaterializer. Call MaterializeAllPermanently" 392 " to clear it out before setting another one."); 393 Materializer.reset(GVM); 394 } 395 396 bool Module::isMaterializable(const GlobalValue *GV) const { 397 if (Materializer) 398 return Materializer->isMaterializable(GV); 399 return false; 400 } 401 402 bool Module::isDematerializable(const GlobalValue *GV) const { 403 if (Materializer) 404 return Materializer->isDematerializable(GV); 405 return false; 406 } 407 408 bool Module::Materialize(GlobalValue *GV, std::string *ErrInfo) { 409 if (Materializer) 410 return Materializer->Materialize(GV, ErrInfo); 411 return false; 412 } 413 414 void Module::Dematerialize(GlobalValue *GV) { 415 if (Materializer) 416 return Materializer->Dematerialize(GV); 417 } 418 419 bool Module::MaterializeAll(std::string *ErrInfo) { 420 if (!Materializer) 421 return false; 422 return Materializer->MaterializeModule(this, ErrInfo); 423 } 424 425 bool Module::MaterializeAllPermanently(std::string *ErrInfo) { 426 if (MaterializeAll(ErrInfo)) 427 return true; 428 Materializer.reset(); 429 return false; 430 } 431 432 //===----------------------------------------------------------------------===// 433 // Other module related stuff. 434 // 435 436 437 // dropAllReferences() - This function causes all the subelements to "let go" 438 // of all references that they are maintaining. This allows one to 'delete' a 439 // whole module at a time, even though there may be circular references... first 440 // all references are dropped, and all use counts go to zero. Then everything 441 // is deleted for real. Note that no operations are valid on an object that 442 // has "dropped all references", except operator delete. 443 // 444 void Module::dropAllReferences() { 445 for(Module::iterator I = begin(), E = end(); I != E; ++I) 446 I->dropAllReferences(); 447 448 for(Module::global_iterator I = global_begin(), E = global_end(); I != E; ++I) 449 I->dropAllReferences(); 450 451 for(Module::alias_iterator I = alias_begin(), E = alias_end(); I != E; ++I) 452 I->dropAllReferences(); 453 } 454 455 void Module::addLibrary(StringRef Lib) { 456 for (Module::lib_iterator I = lib_begin(), E = lib_end(); I != E; ++I) 457 if (*I == Lib) 458 return; 459 LibraryList.push_back(Lib); 460 } 461 462 void Module::removeLibrary(StringRef Lib) { 463 LibraryListType::iterator I = LibraryList.begin(); 464 LibraryListType::iterator E = LibraryList.end(); 465 for (;I != E; ++I) 466 if (*I == Lib) { 467 LibraryList.erase(I); 468 return; 469 } 470 } 471 472 //===----------------------------------------------------------------------===// 473 // Type finding functionality. 474 //===----------------------------------------------------------------------===// 475 476 namespace { 477 /// TypeFinder - Walk over a module, identifying all of the types that are 478 /// used by the module. 479 class TypeFinder { 480 // To avoid walking constant expressions multiple times and other IR 481 // objects, we keep several helper maps. 482 DenseSet<const Value*> VisitedConstants; 483 DenseSet<Type*> VisitedTypes; 484 485 std::vector<StructType*> &StructTypes; 486 public: 487 TypeFinder(std::vector<StructType*> &structTypes) 488 : StructTypes(structTypes) {} 489 490 void run(const Module &M) { 491 // Get types from global variables. 492 for (Module::const_global_iterator I = M.global_begin(), 493 E = M.global_end(); I != E; ++I) { 494 incorporateType(I->getType()); 495 if (I->hasInitializer()) 496 incorporateValue(I->getInitializer()); 497 } 498 499 // Get types from aliases. 500 for (Module::const_alias_iterator I = M.alias_begin(), 501 E = M.alias_end(); I != E; ++I) { 502 incorporateType(I->getType()); 503 if (const Value *Aliasee = I->getAliasee()) 504 incorporateValue(Aliasee); 505 } 506 507 SmallVector<std::pair<unsigned, MDNode*>, 4> MDForInst; 508 509 // Get types from functions. 510 for (Module::const_iterator FI = M.begin(), E = M.end(); FI != E; ++FI) { 511 incorporateType(FI->getType()); 512 513 for (Function::const_iterator BB = FI->begin(), E = FI->end(); 514 BB != E;++BB) 515 for (BasicBlock::const_iterator II = BB->begin(), 516 E = BB->end(); II != E; ++II) { 517 const Instruction &I = *II; 518 // Incorporate the type of the instruction and all its operands. 519 incorporateType(I.getType()); 520 for (User::const_op_iterator OI = I.op_begin(), OE = I.op_end(); 521 OI != OE; ++OI) 522 incorporateValue(*OI); 523 524 // Incorporate types hiding in metadata. 525 I.getAllMetadataOtherThanDebugLoc(MDForInst); 526 for (unsigned i = 0, e = MDForInst.size(); i != e; ++i) 527 incorporateMDNode(MDForInst[i].second); 528 MDForInst.clear(); 529 } 530 } 531 532 for (Module::const_named_metadata_iterator I = M.named_metadata_begin(), 533 E = M.named_metadata_end(); I != E; ++I) { 534 const NamedMDNode *NMD = I; 535 for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i) 536 incorporateMDNode(NMD->getOperand(i)); 537 } 538 } 539 540 private: 541 void incorporateType(Type *Ty) { 542 // Check to see if we're already visited this type. 543 if (!VisitedTypes.insert(Ty).second) 544 return; 545 546 // If this is a structure or opaque type, add a name for the type. 547 if (StructType *STy = dyn_cast<StructType>(Ty)) 548 StructTypes.push_back(STy); 549 550 // Recursively walk all contained types. 551 for (Type::subtype_iterator I = Ty->subtype_begin(), 552 E = Ty->subtype_end(); I != E; ++I) 553 incorporateType(*I); 554 } 555 556 /// incorporateValue - This method is used to walk operand lists finding 557 /// types hiding in constant expressions and other operands that won't be 558 /// walked in other ways. GlobalValues, basic blocks, instructions, and 559 /// inst operands are all explicitly enumerated. 560 void incorporateValue(const Value *V) { 561 if (const MDNode *M = dyn_cast<MDNode>(V)) 562 return incorporateMDNode(M); 563 if (!isa<Constant>(V) || isa<GlobalValue>(V)) return; 564 565 // Already visited? 566 if (!VisitedConstants.insert(V).second) 567 return; 568 569 // Check this type. 570 incorporateType(V->getType()); 571 572 // Look in operands for types. 573 const User *U = cast<User>(V); 574 for (Constant::const_op_iterator I = U->op_begin(), 575 E = U->op_end(); I != E;++I) 576 incorporateValue(*I); 577 } 578 579 void incorporateMDNode(const MDNode *V) { 580 581 // Already visited? 582 if (!VisitedConstants.insert(V).second) 583 return; 584 585 // Look in operands for types. 586 for (unsigned i = 0, e = V->getNumOperands(); i != e; ++i) 587 if (Value *Op = V->getOperand(i)) 588 incorporateValue(Op); 589 } 590 }; 591 } // end anonymous namespace 592 593 void Module::findUsedStructTypes(std::vector<StructType*> &StructTypes) const { 594 TypeFinder(StructTypes).run(*this); 595 } 596