lib/VMCore/Module.cpp

   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/LLVMContext.h"
  19 #include "llvm/ADT/STLExtras.h"
  20 #include "llvm/ADT/StringExtras.h"
  21 #include "llvm/Support/LeakDetector.h"
  22 #include "SymbolTableListTraitsImpl.h"
  23 #include "llvm/TypeSymbolTable.h"
  24 #include <algorithm>
  25 #include <cstdarg>
  26 #include <cstdlib>
  27 using namespace llvm;
  28
  29 //===----------------------------------------------------------------------===//
  30 // Methods to implement the globals and functions lists.
  31 //
  32
  33 GlobalVariable *ilist_traits<GlobalVariable>::createSentinel() {
  34   GlobalVariable *Ret = new GlobalVariable(getGlobalContext(), Type::Int32Ty,
  35                                            false, GlobalValue::ExternalLinkage);
  36   // This should not be garbage monitored.
  37   LeakDetector::removeGarbageObject(Ret);
  38   return Ret;
  39 }
  40 GlobalAlias *ilist_traits<GlobalAlias>::createSentinel() {
  41   GlobalAlias *Ret = new GlobalAlias(Type::Int32Ty,
  42                                      GlobalValue::ExternalLinkage);
  43   // This should not be garbage monitored.
  44   LeakDetector::removeGarbageObject(Ret);
  45   return Ret;
  46 }
  47
  48 // Explicit instantiations of SymbolTableListTraits since some of the methods
  49 // are not in the public header file.
  50 template class SymbolTableListTraits<GlobalVariable, Module>;
  51 template class SymbolTableListTraits<Function, Module>;
  52 template class SymbolTableListTraits<GlobalAlias, Module>;
  53
  54 //===----------------------------------------------------------------------===//
  55 // Primitive Module methods.
  56 //
  57
  58 Module::Module(const StringRef &MID, LLVMContext& C)
  59   : Context(C), ModuleID(MID), DataLayout("")  {
  60   ValSymTab = new ValueSymbolTable();
  61   TypeSymTab = new TypeSymbolTable();
  62 }
  63
  64 Module::~Module() {
  65   dropAllReferences();
  66   GlobalList.clear();
  67   FunctionList.clear();
  68   AliasList.clear();
  69   LibraryList.clear();
  70   NamedMDList.clear();
  71   delete ValSymTab;
  72   delete TypeSymTab;
  73 }
  74
  75 /// Target endian information...
  76 Module::Endianness Module::getEndianness() const {
  77   std::string temp = DataLayout;
  78   Module::Endianness ret = AnyEndianness;
  79
  80   while (!temp.empty()) {
  81     std::string token = getToken(temp, "-");
  82
  83     if (token[0] == 'e') {
  84       ret = LittleEndian;
  85     } else if (token[0] == 'E') {
  86       ret = BigEndian;
  87     }
  88   }
  89
  90   return ret;
  91 }
  92
  93 /// Target Pointer Size information...
  94 Module::PointerSize Module::getPointerSize() const {
  95   std::string temp = DataLayout;
  96   Module::PointerSize ret = AnyPointerSize;
  97
  98   while (!temp.empty()) {
  99     std::string token = getToken(temp, "-");
 100     char signal = getToken(token, ":")[0];
 101
 102     if (signal == 'p') {
 103       int size = atoi(getToken(token, ":").c_str());
 104       if (size == 32)
 105         ret = Pointer32;
 106       else if (size == 64)
 107         ret = Pointer64;
 108     }
 109   }
 110
 111   return ret;
 112 }
 113
 114 /// getNamedValue - Return the first global value in the module with
 115 /// the specified name, of arbitrary type.  This method returns null
 116 /// if a global with the specified name is not found.
 117 GlobalValue *Module::getNamedValue(const StringRef &Name) const {
 118   return cast_or_null<GlobalValue>(getValueSymbolTable().lookup(Name));
 119 }
 120
 121 //===----------------------------------------------------------------------===//
 122 // Methods for easy access to the functions in the module.
 123 //
 124
 125 // getOrInsertFunction - Look up the specified function in the module symbol
 126 // table.  If it does not exist, add a prototype for the function and return
 127 // it.  This is nice because it allows most passes to get away with not handling
 128 // the symbol table directly for this common task.
 129 //
 130 Constant *Module::getOrInsertFunction(const StringRef &Name,
 131                                       const FunctionType *Ty,
 132                                       AttrListPtr AttributeList) {
 133   // See if we have a definition for the specified function already.
 134   GlobalValue *F = getNamedValue(Name);
 135   if (F == 0) {
 136     // Nope, add it
 137     Function *New = Function::Create(Ty, GlobalVariable::ExternalLinkage, Name);
 138     if (!New->isIntrinsic())       // Intrinsics get attrs set on construction
 139       New->setAttributes(AttributeList);
 140     FunctionList.push_back(New);
 141     return New;                    // Return the new prototype.
 142   }
 143
 144   // Okay, the function exists.  Does it have externally visible linkage?
 145   if (F->hasLocalLinkage()) {
 146     // Clear the function's name.
 147     F->setName("");
 148     // Retry, now there won't be a conflict.
 149     Constant *NewF = getOrInsertFunction(Name, Ty);
 150     F->setName(Name);
 151     return NewF;
 152   }
 153
 154   // If the function exists but has the wrong type, return a bitcast to the
 155   // right type.
 156   if (F->getType() != PointerType::getUnqual(Ty))
 157     return ConstantExpr::getBitCast(F, PointerType::getUnqual(Ty));
 158
 159   // Otherwise, we just found the existing function or a prototype.
 160   return F;
 161 }
 162
 163 Constant *Module::getOrInsertTargetIntrinsic(const StringRef &Name,
 164                                              const FunctionType *Ty,
 165                                              AttrListPtr AttributeList) {
 166   // See if we have a definition for the specified function already.
 167   GlobalValue *F = getNamedValue(Name);
 168   if (F == 0) {
 169     // Nope, add it
 170     Function *New = Function::Create(Ty, GlobalVariable::ExternalLinkage, Name);
 171     New->setAttributes(AttributeList);
 172     FunctionList.push_back(New);
 173     return New; // Return the new prototype.
 174   }
 175
 176   // Otherwise, we just found the existing function or a prototype.
 177   return F;
 178 }
 179
 180 Constant *Module::getOrInsertFunction(const StringRef &Name,
 181                                       const FunctionType *Ty) {
 182   AttrListPtr AttributeList = AttrListPtr::get((AttributeWithIndex *)0, 0);
 183   return getOrInsertFunction(Name, Ty, AttributeList);
 184 }
 185
 186 // getOrInsertFunction - Look up the specified function in the module symbol
 187 // table.  If it does not exist, add a prototype for the function and return it.
 188 // This version of the method takes a null terminated list of function
 189 // arguments, which makes it easier for clients to use.
 190 //
 191 Constant *Module::getOrInsertFunction(const StringRef &Name,
 192                                       AttrListPtr AttributeList,
 193                                       const Type *RetTy, ...) {
 194   va_list Args;
 195   va_start(Args, RetTy);
 196
 197   // Build the list of argument types...
 198   std::vector<const Type*> ArgTys;
 199   while (const Type *ArgTy = va_arg(Args, const Type*))
 200     ArgTys.push_back(ArgTy);
 201
 202   va_end(Args);
 203
 204   // Build the function type and chain to the other getOrInsertFunction...
 205   return getOrInsertFunction(Name,
 206                              FunctionType::get(RetTy, ArgTys, false),
 207                              AttributeList);
 208 }
 209
 210 Constant *Module::getOrInsertFunction(const StringRef &Name,
 211                                       const Type *RetTy, ...) {
 212   va_list Args;
 213   va_start(Args, RetTy);
 214
 215   // Build the list of argument types...
 216   std::vector<const Type*> ArgTys;
 217   while (const Type *ArgTy = va_arg(Args, const Type*))
 218     ArgTys.push_back(ArgTy);
 219
 220   va_end(Args);
 221
 222   // Build the function type and chain to the other getOrInsertFunction...
 223   return getOrInsertFunction(Name,
 224                              FunctionType::get(RetTy, ArgTys, false),
 225                              AttrListPtr::get((AttributeWithIndex *)0, 0));
 226 }
 227
 228 // getFunction - Look up the specified function in the module symbol table.
 229 // If it does not exist, return null.
 230 //
 231 Function *Module::getFunction(const StringRef &Name) const {
 232   return dyn_cast_or_null<Function>(getNamedValue(Name));
 233 }
 234
 235 //===----------------------------------------------------------------------===//
 236 // Methods for easy access to the global variables in the module.
 237 //
 238
 239 /// getGlobalVariable - Look up the specified global variable in the module
 240 /// symbol table.  If it does not exist, return null.  The type argument
 241 /// should be the underlying type of the global, i.e., it should not have
 242 /// the top-level PointerType, which represents the address of the global.
 243 /// If AllowLocal is set to true, this function will return types that
 244 /// have an local. By default, these types are not returned.
 245 ///
 246 GlobalVariable *Module::getGlobalVariable(const StringRef &Name,
 247                                           bool AllowLocal) const {
 248   if (GlobalVariable *Result =
 249       dyn_cast_or_null<GlobalVariable>(getNamedValue(Name)))
 250     if (AllowLocal || !Result->hasLocalLinkage())
 251       return Result;
 252   return 0;
 253 }
 254
 255 /// getOrInsertGlobal - Look up the specified global in the module symbol table.
 256 ///   1. If it does not exist, add a declaration of the global and return it.
 257 ///   2. Else, the global exists but has the wrong type: return the function
 258 ///      with a constantexpr cast to the right type.
 259 ///   3. Finally, if the existing global is the correct delclaration, return the
 260 ///      existing global.
 261 Constant *Module::getOrInsertGlobal(const StringRef &Name, const Type *Ty) {
 262   // See if we have a definition for the specified global already.
 263   GlobalVariable *GV = dyn_cast_or_null<GlobalVariable>(getNamedValue(Name));
 264   if (GV == 0) {
 265     // Nope, add it
 266     GlobalVariable *New =
 267       new GlobalVariable(*this, Ty, false, GlobalVariable::ExternalLinkage,
 268                          0, Name);
 269      return New;                    // Return the new declaration.
 270   }
 271
 272   // If the variable exists but has the wrong type, return a bitcast to the
 273   // right type.
 274   if (GV->getType() != PointerType::getUnqual(Ty))
 275     return ConstantExpr::getBitCast(GV, PointerType::getUnqual(Ty));
 276
 277   // Otherwise, we just found the existing function or a prototype.
 278   return GV;
 279 }
 280
 281 //===----------------------------------------------------------------------===//
 282 // Methods for easy access to the global variables in the module.
 283 //
 284
 285 // getNamedAlias - Look up the specified global in the module symbol table.
 286 // If it does not exist, return null.
 287 //
 288 GlobalAlias *Module::getNamedAlias(const StringRef &Name) const {
 289   return dyn_cast_or_null<GlobalAlias>(getNamedValue(Name));
 290 }
 291
 292 /// getNamedMetadata - Return the first NamedMDNode in the module with the
 293 /// specified name. This method returns null if a NamedMDNode with the
 294 //// specified name is not found.
 295 NamedMDNode *Module::getNamedMetadata(const StringRef &Name) const {
 296   return dyn_cast_or_null<NamedMDNode>(getValueSymbolTable().lookup(Name));
 297 }
 298
 299 /// getOrInsertNamedMetadata - Return the first named MDNode in the module
 300 /// with the specified name. This method returns a new NamedMDNode if a
 301 /// NamedMDNode with the specified name is not found.
 302 NamedMDNode *Module::getOrInsertNamedMetadata(const StringRef &Name) {
 303   NamedMDNode *NMD =
 304     dyn_cast_or_null<NamedMDNode>(getValueSymbolTable().lookup(Name));
 305   if (!NMD)
 306     NMD = NamedMDNode::Create(Name, NULL, 0, this);
 307   return NMD;
 308 }
 309
 310 //===----------------------------------------------------------------------===//
 311 // Methods for easy access to the types in the module.
 312 //
 313
 314
 315 // addTypeName - Insert an entry in the symbol table mapping Str to Type.  If
 316 // there is already an entry for this name, true is returned and the symbol
 317 // table is not modified.
 318 //
 319 bool Module::addTypeName(const StringRef &Name, const Type *Ty) {
 320   TypeSymbolTable &ST = getTypeSymbolTable();
 321
 322   if (ST.lookup(Name)) return true;  // Already in symtab...
 323
 324   // Not in symbol table?  Set the name with the Symtab as an argument so the
 325   // type knows what to update...
 326   ST.insert(Name, Ty);
 327
 328   return false;
 329 }
 330
 331 /// getTypeByName - Return the type with the specified name in this module, or
 332 /// null if there is none by that name.
 333 const Type *Module::getTypeByName(const StringRef &Name) const {
 334   const TypeSymbolTable &ST = getTypeSymbolTable();
 335   return cast_or_null<Type>(ST.lookup(Name));
 336 }
 337
 338 // getTypeName - If there is at least one entry in the symbol table for the
 339 // specified type, return it.
 340 //
 341 std::string Module::getTypeName(const Type *Ty) const {
 342   const TypeSymbolTable &ST = getTypeSymbolTable();
 343
 344   TypeSymbolTable::const_iterator TI = ST.begin();
 345   TypeSymbolTable::const_iterator TE = ST.end();
 346   if ( TI == TE ) return ""; // No names for types
 347
 348   while (TI != TE && TI->second != Ty)
 349     ++TI;
 350
 351   if (TI != TE)  // Must have found an entry!
 352     return TI->first;
 353   return "";     // Must not have found anything...
 354 }
 355
 356 //===----------------------------------------------------------------------===//
 357 // Other module related stuff.
 358 //
 359
 360
 361 // dropAllReferences() - This function causes all the subelementss to "let go"
 362 // of all references that they are maintaining.  This allows one to 'delete' a
 363 // whole module at a time, even though there may be circular references... first
 364 // all references are dropped, and all use counts go to zero.  Then everything
 365 // is deleted for real.  Note that no operations are valid on an object that
 366 // has "dropped all references", except operator delete.
 367 //
 368 void Module::dropAllReferences() {
 369   for(Module::iterator I = begin(), E = end(); I != E; ++I)
 370     I->dropAllReferences();
 371
 372   for(Module::global_iterator I = global_begin(), E = global_end(); I != E; ++I)
 373     I->dropAllReferences();
 374
 375   for(Module::alias_iterator I = alias_begin(), E = alias_end(); I != E; ++I)
 376     I->dropAllReferences();
 377 }
 378
 379 void Module::addLibrary(const StringRef& Lib) {
 380   for (Module::lib_iterator I = lib_begin(), E = lib_end(); I != E; ++I)
 381     if (*I == Lib)
 382       return;
 383   LibraryList.push_back(Lib);
 384 }
 385
 386 void Module::removeLibrary(const StringRef& Lib) {
 387   LibraryListType::iterator I = LibraryList.begin();
 388   LibraryListType::iterator E = LibraryList.end();
 389   for (;I != E; ++I)
 390     if (*I == Lib) {
 391       LibraryList.erase(I);
 392       return;
 393     }
 394 }