LLVM API Documentation
00001 //===-- Module.cpp - Implement the Module class ---------------------------===// 00002 // 00003 // The LLVM Compiler Infrastructure 00004 // 00005 // This file was developed by the LLVM research group and is distributed under 00006 // the University of Illinois Open Source License. See LICENSE.TXT for details. 00007 // 00008 //===----------------------------------------------------------------------===// 00009 // 00010 // This file implements the Module class for the VMCore library. 00011 // 00012 //===----------------------------------------------------------------------===// 00013 00014 #include "llvm/Module.h" 00015 #include "llvm/InstrTypes.h" 00016 #include "llvm/Constants.h" 00017 #include "llvm/DerivedTypes.h" 00018 #include "llvm/ADT/STLExtras.h" 00019 #include "llvm/ADT/StringExtras.h" 00020 #include "llvm/Support/LeakDetector.h" 00021 #include "SymbolTableListTraitsImpl.h" 00022 #include <algorithm> 00023 #include <cstdarg> 00024 #include <cstdlib> 00025 #include <iostream> 00026 #include <map> 00027 using namespace llvm; 00028 00029 //===----------------------------------------------------------------------===// 00030 // Methods to implement the globals and functions lists. 00031 // 00032 00033 Function *ilist_traits<Function>::createSentinel() { 00034 FunctionType *FTy = 00035 FunctionType::get(Type::VoidTy, std::vector<const Type*>(), false); 00036 Function *Ret = new Function(FTy, GlobalValue::ExternalLinkage); 00037 // This should not be garbage monitored. 00038 LeakDetector::removeGarbageObject(Ret); 00039 return Ret; 00040 } 00041 GlobalVariable *ilist_traits<GlobalVariable>::createSentinel() { 00042 GlobalVariable *Ret = new GlobalVariable(Type::IntTy, false, 00043 GlobalValue::ExternalLinkage); 00044 // This should not be garbage monitored. 00045 LeakDetector::removeGarbageObject(Ret); 00046 return Ret; 00047 } 00048 00049 iplist<Function> &ilist_traits<Function>::getList(Module *M) { 00050 return M->getFunctionList(); 00051 } 00052 iplist<GlobalVariable> &ilist_traits<GlobalVariable>::getList(Module *M) { 00053 return M->getGlobalList(); 00054 } 00055 00056 // Explicit instantiations of SymbolTableListTraits since some of the methods 00057 // are not in the public header file. 00058 template class SymbolTableListTraits<GlobalVariable, Module, Module>; 00059 template class SymbolTableListTraits<Function, Module, Module>; 00060 00061 //===----------------------------------------------------------------------===// 00062 // Primitive Module methods. 00063 // 00064 00065 Module::Module(const std::string &MID) 00066 : ModuleID(MID), DataLayout("") { 00067 FunctionList.setItemParent(this); 00068 FunctionList.setParent(this); 00069 GlobalList.setItemParent(this); 00070 GlobalList.setParent(this); 00071 SymTab = new SymbolTable(); 00072 } 00073 00074 Module::~Module() { 00075 dropAllReferences(); 00076 GlobalList.clear(); 00077 GlobalList.setParent(0); 00078 FunctionList.clear(); 00079 FunctionList.setParent(0); 00080 LibraryList.clear(); 00081 delete SymTab; 00082 } 00083 00084 // Module::dump() - Allow printing from debugger 00085 void Module::dump() const { 00086 print(std::cerr); 00087 } 00088 00089 /// Target endian information... 00090 Module::Endianness Module::getEndianness() const { 00091 std::string temp = DataLayout; 00092 Module::Endianness ret = AnyEndianness; 00093 00094 while (!temp.empty()) { 00095 std::string token = getToken(temp, "-"); 00096 00097 if (token[0] == 'e') { 00098 ret = LittleEndian; 00099 } else if (token[0] == 'E') { 00100 ret = BigEndian; 00101 } 00102 } 00103 00104 return ret; 00105 } 00106 00107 void Module::setEndianness(Endianness E) { 00108 if (!DataLayout.empty() && E != AnyEndianness) 00109 DataLayout += "-"; 00110 00111 if (E == LittleEndian) 00112 DataLayout += "e"; 00113 else if (E == BigEndian) 00114 DataLayout += "E"; 00115 } 00116 00117 /// Target Pointer Size information... 00118 Module::PointerSize Module::getPointerSize() const { 00119 std::string temp = DataLayout; 00120 Module::PointerSize ret = AnyPointerSize; 00121 00122 while (!temp.empty()) { 00123 std::string token = getToken(temp, "-"); 00124 char signal = getToken(token, ":")[0]; 00125 00126 if (signal == 'p') { 00127 int size = atoi(getToken(token, ":").c_str()); 00128 if (size == 32) 00129 ret = Pointer32; 00130 else if (size == 64) 00131 ret = Pointer64; 00132 } 00133 } 00134 00135 return ret; 00136 } 00137 00138 void Module::setPointerSize(PointerSize PS) { 00139 if (!DataLayout.empty() && PS != AnyPointerSize) 00140 DataLayout += "-"; 00141 00142 if (PS == Pointer32) 00143 DataLayout += "p:32:32"; 00144 else if (PS == Pointer64) 00145 DataLayout += "p:64:64"; 00146 } 00147 00148 //===----------------------------------------------------------------------===// 00149 // Methods for easy access to the functions in the module. 00150 // 00151 00152 // getOrInsertFunction - Look up the specified function in the module symbol 00153 // table. If it does not exist, add a prototype for the function and return 00154 // it. This is nice because it allows most passes to get away with not handling 00155 // the symbol table directly for this common task. 00156 // 00157 Function *Module::getOrInsertFunction(const std::string &Name, 00158 const FunctionType *Ty) { 00159 SymbolTable &SymTab = getSymbolTable(); 00160 00161 // See if we have a definitions for the specified function already... 00162 if (Value *V = SymTab.lookup(PointerType::get(Ty), Name)) { 00163 return cast<Function>(V); // Yup, got it 00164 } else { // Nope, add one 00165 Function *New = new Function(Ty, GlobalVariable::ExternalLinkage, Name); 00166 FunctionList.push_back(New); 00167 return New; // Return the new prototype... 00168 } 00169 } 00170 00171 // getOrInsertFunction - Look up the specified function in the module symbol 00172 // table. If it does not exist, add a prototype for the function and return it. 00173 // This version of the method takes a null terminated list of function 00174 // arguments, which makes it easier for clients to use. 00175 // 00176 Function *Module::getOrInsertFunction(const std::string &Name, 00177 const Type *RetTy, ...) { 00178 va_list Args; 00179 va_start(Args, RetTy); 00180 00181 // Build the list of argument types... 00182 std::vector<const Type*> ArgTys; 00183 while (const Type *ArgTy = va_arg(Args, const Type*)) 00184 ArgTys.push_back(ArgTy); 00185 00186 va_end(Args); 00187 00188 // Build the function type and chain to the other getOrInsertFunction... 00189 return getOrInsertFunction(Name, FunctionType::get(RetTy, ArgTys, false)); 00190 } 00191 00192 00193 // getFunction - Look up the specified function in the module symbol table. 00194 // If it does not exist, return null. 00195 // 00196 Function *Module::getFunction(const std::string &Name, const FunctionType *Ty) { 00197 SymbolTable &SymTab = getSymbolTable(); 00198 return cast_or_null<Function>(SymTab.lookup(PointerType::get(Ty), Name)); 00199 } 00200 00201 00202 /// getMainFunction - This function looks up main efficiently. This is such a 00203 /// common case, that it is a method in Module. If main cannot be found, a 00204 /// null pointer is returned. 00205 /// 00206 Function *Module::getMainFunction() { 00207 std::vector<const Type*> Params; 00208 00209 // int main(void)... 00210 if (Function *F = getFunction("main", FunctionType::get(Type::IntTy, 00211 Params, false))) 00212 return F; 00213 00214 // void main(void)... 00215 if (Function *F = getFunction("main", FunctionType::get(Type::VoidTy, 00216 Params, false))) 00217 return F; 00218 00219 Params.push_back(Type::IntTy); 00220 00221 // int main(int argc)... 00222 if (Function *F = getFunction("main", FunctionType::get(Type::IntTy, 00223 Params, false))) 00224 return F; 00225 00226 // void main(int argc)... 00227 if (Function *F = getFunction("main", FunctionType::get(Type::VoidTy, 00228 Params, false))) 00229 return F; 00230 00231 for (unsigned i = 0; i != 2; ++i) { // Check argv and envp 00232 Params.push_back(PointerType::get(PointerType::get(Type::SByteTy))); 00233 00234 // int main(int argc, char **argv)... 00235 if (Function *F = getFunction("main", FunctionType::get(Type::IntTy, 00236 Params, false))) 00237 return F; 00238 00239 // void main(int argc, char **argv)... 00240 if (Function *F = getFunction("main", FunctionType::get(Type::VoidTy, 00241 Params, false))) 00242 return F; 00243 } 00244 00245 // Ok, try to find main the hard way... 00246 return getNamedFunction("main"); 00247 } 00248 00249 /// getNamedFunction - Return the first function in the module with the 00250 /// specified name, of arbitrary type. This method returns null if a function 00251 /// with the specified name is not found. 00252 /// 00253 Function *Module::getNamedFunction(const std::string &Name) const { 00254 // Loop over all of the functions, looking for the function desired 00255 const Function *Found = 0; 00256 for (const_iterator I = begin(), E = end(); I != E; ++I) 00257 if (I->getName() == Name) 00258 if (I->isExternal()) 00259 Found = I; 00260 else 00261 return const_cast<Function*>(&(*I)); 00262 return const_cast<Function*>(Found); // Non-external function not found... 00263 } 00264 00265 //===----------------------------------------------------------------------===// 00266 // Methods for easy access to the global variables in the module. 00267 // 00268 00269 /// getGlobalVariable - Look up the specified global variable in the module 00270 /// symbol table. If it does not exist, return null. The type argument 00271 /// should be the underlying type of the global, i.e., it should not have 00272 /// the top-level PointerType, which represents the address of the global. 00273 /// If AllowInternal is set to true, this function will return types that 00274 /// have InternalLinkage. By default, these types are not returned. 00275 /// 00276 GlobalVariable *Module::getGlobalVariable(const std::string &Name, 00277 const Type *Ty, bool AllowInternal) { 00278 if (Value *V = getSymbolTable().lookup(PointerType::get(Ty), Name)) { 00279 GlobalVariable *Result = cast<GlobalVariable>(V); 00280 if (AllowInternal || !Result->hasInternalLinkage()) 00281 return Result; 00282 } 00283 return 0; 00284 } 00285 00286 /// getNamedGlobal - Return the first global variable in the module with the 00287 /// specified name, of arbitrary type. This method returns null if a global 00288 /// with the specified name is not found. 00289 /// 00290 GlobalVariable *Module::getNamedGlobal(const std::string &Name) const { 00291 // FIXME: This would be much faster with a symbol table that doesn't 00292 // discriminate based on type! 00293 for (const_global_iterator I = global_begin(), E = global_end(); 00294 I != E; ++I) 00295 if (I->getName() == Name) 00296 return const_cast<GlobalVariable*>(&(*I)); 00297 return 0; 00298 } 00299 00300 00301 00302 //===----------------------------------------------------------------------===// 00303 // Methods for easy access to the types in the module. 00304 // 00305 00306 00307 // addTypeName - Insert an entry in the symbol table mapping Str to Type. If 00308 // there is already an entry for this name, true is returned and the symbol 00309 // table is not modified. 00310 // 00311 bool Module::addTypeName(const std::string &Name, const Type *Ty) { 00312 SymbolTable &ST = getSymbolTable(); 00313 00314 if (ST.lookupType(Name)) return true; // Already in symtab... 00315 00316 // Not in symbol table? Set the name with the Symtab as an argument so the 00317 // type knows what to update... 00318 ST.insert(Name, Ty); 00319 00320 return false; 00321 } 00322 00323 /// getTypeByName - Return the type with the specified name in this module, or 00324 /// null if there is none by that name. 00325 const Type *Module::getTypeByName(const std::string &Name) const { 00326 const SymbolTable &ST = getSymbolTable(); 00327 return cast_or_null<Type>(ST.lookupType(Name)); 00328 } 00329 00330 // getTypeName - If there is at least one entry in the symbol table for the 00331 // specified type, return it. 00332 // 00333 std::string Module::getTypeName(const Type *Ty) const { 00334 const SymbolTable &ST = getSymbolTable(); 00335 00336 SymbolTable::type_const_iterator TI = ST.type_begin(); 00337 SymbolTable::type_const_iterator TE = ST.type_end(); 00338 if ( TI == TE ) return ""; // No names for types 00339 00340 while (TI != TE && TI->second != Ty) 00341 ++TI; 00342 00343 if (TI != TE) // Must have found an entry! 00344 return TI->first; 00345 return ""; // Must not have found anything... 00346 } 00347 00348 //===----------------------------------------------------------------------===// 00349 // Other module related stuff. 00350 // 00351 00352 00353 // dropAllReferences() - This function causes all the subelementss to "let go" 00354 // of all references that they are maintaining. This allows one to 'delete' a 00355 // whole module at a time, even though there may be circular references... first 00356 // all references are dropped, and all use counts go to zero. Then everything 00357 // is deleted for real. Note that no operations are valid on an object that 00358 // has "dropped all references", except operator delete. 00359 // 00360 void Module::dropAllReferences() { 00361 for(Module::iterator I = begin(), E = end(); I != E; ++I) 00362 I->dropAllReferences(); 00363 00364 for(Module::global_iterator I = global_begin(), E = global_end(); I != E; ++I) 00365 I->dropAllReferences(); 00366 } 00367