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/GVMaterializer.h"
  19 #include "llvm/LLVMContext.h"
  20 #include "llvm/ADT/SmallString.h"
  21 #include "llvm/ADT/STLExtras.h"
  22 #include "llvm/ADT/StringExtras.h"
  23 #include "llvm/Support/LeakDetector.h"
  24 #include "SymbolTableListTraitsImpl.h"
  25 #include "llvm/TypeSymbolTable.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 GlobalVariable *ilist_traits<GlobalVariable>::createSentinel() {
  36   GlobalVariable *Ret = new GlobalVariable(Type::getInt32Ty(getGlobalContext()),
  37                                            false, GlobalValue::ExternalLinkage);
  38   // This should not be garbage monitored.
  39   LeakDetector::removeGarbageObject(Ret);
  40   return Ret;
  41 }
  42 GlobalAlias *ilist_traits<GlobalAlias>::createSentinel() {
  43   GlobalAlias *Ret = new GlobalAlias(Type::getInt32Ty(getGlobalContext()),
  44                                      GlobalValue::ExternalLinkage);
  45   // This should not be garbage monitored.
  46   LeakDetector::removeGarbageObject(Ret);
  47   return Ret;
  48 }
  49
  50 // Explicit instantiations of SymbolTableListTraits since some of the methods
  51 // are not in the public header file.
  52 template class llvm::SymbolTableListTraits<GlobalVariable, Module>;
  53 template class llvm::SymbolTableListTraits<Function, Module>;
  54 template class llvm::SymbolTableListTraits<GlobalAlias, Module>;
  55
  56 //===----------------------------------------------------------------------===//
  57 // Primitive Module methods.
  58 //
  59
  60 Module::Module(StringRef MID, LLVMContext& C)
  61   : Context(C), Materializer(NULL), ModuleID(MID) {
  62   ValSymTab = new ValueSymbolTable();
  63   TypeSymTab = new TypeSymbolTable();
  64   NamedMDSymTab = new StringMap<NamedMDNode *>();
  65   Context.addModule(this);
  66 }
  67
  68 Module::~Module() {
  69   Context.removeModule(this);
  70   dropAllReferences();
  71   GlobalList.clear();
  72   FunctionList.clear();
  73   AliasList.clear();
  74   LibraryList.clear();
  75   NamedMDList.clear();
  76   delete ValSymTab;
  77   delete TypeSymTab;
  78   delete static_cast<StringMap<NamedMDNode *> *>(NamedMDSymTab);
  79 }
  80
  81 /// Target endian information...
  82 Module::Endianness Module::getEndianness() const {
  83   StringRef temp = DataLayout;
  84   Module::Endianness ret = AnyEndianness;
  85
  86   while (!temp.empty()) {
  87     StringRef token = DataLayout;
  88     tie(token, temp) = getToken(temp, "-");
  89
  90     if (token[0] == 'e') {
  91       ret = LittleEndian;
  92     } else if (token[0] == 'E') {
  93       ret = BigEndian;
  94     }
  95   }
  96
  97   return ret;
  98 }
  99
 100 /// Target Pointer Size information...
 101 Module::PointerSize Module::getPointerSize() const {
 102   StringRef temp = DataLayout;
 103   Module::PointerSize ret = AnyPointerSize;
 104
 105   while (!temp.empty()) {
 106     StringRef token, signalToken;
 107     tie(token, temp) = getToken(temp, "-");
 108     tie(signalToken, token) = getToken(token, ":");
 109
 110     if (signalToken[0] == 'p') {
 111       int size = 0;
 112       getToken(token, ":").first.getAsInteger(10, size);
 113       if (size == 32)
 114         ret = Pointer32;
 115       else if (size == 64)
 116         ret = Pointer64;
 117     }
 118   }
 119
 120   return ret;
 121 }
 122
 123 /// getNamedValue - Return the first global value in the module with
 124 /// the specified name, of arbitrary type.  This method returns null
 125 /// if a global with the specified name is not found.
 126 GlobalValue *Module::getNamedValue(StringRef Name) const {
 127   return cast_or_null<GlobalValue>(getValueSymbolTable().lookup(Name));
 128 }
 129
 130 /// getMDKindID - Return a unique non-zero ID for the specified metadata kind.
 131 /// This ID is uniqued across modules in the current LLVMContext.
 132 unsigned Module::getMDKindID(StringRef Name) const {
 133   return Context.getMDKindID(Name);
 134 }
 135
 136 /// getMDKindNames - Populate client supplied SmallVector with the name for
 137 /// custom metadata IDs registered in this LLVMContext.   ID #0 is not used,
 138 /// so it is filled in as an empty string.
 139 void Module::getMDKindNames(SmallVectorImpl<StringRef> &Result) const {
 140   return Context.getMDKindNames(Result);
 141 }
 142
 143
 144 //===----------------------------------------------------------------------===//
 145 // Methods for easy access to the functions in the module.
 146 //
 147
 148 // getOrInsertFunction - Look up the specified function in the module symbol
 149 // table.  If it does not exist, add a prototype for the function and return
 150 // it.  This is nice because it allows most passes to get away with not handling
 151 // the symbol table directly for this common task.
 152 //
 153 Constant *Module::getOrInsertFunction(StringRef Name,
 154                                       const FunctionType *Ty,
 155                                       AttrListPtr AttributeList) {
 156   // See if we have a definition for the specified function already.
 157   GlobalValue *F = getNamedValue(Name);
 158   if (F == 0) {
 159     // Nope, add it
 160     Function *New = Function::Create(Ty, GlobalVariable::ExternalLinkage, Name);
 161     if (!New->isIntrinsic())       // Intrinsics get attrs set on construction
 162       New->setAttributes(AttributeList);
 163     FunctionList.push_back(New);
 164     return New;                    // Return the new prototype.
 165   }
 166
 167   // Okay, the function exists.  Does it have externally visible linkage?
 168   if (F->hasLocalLinkage()) {
 169     // Clear the function's name.
 170     F->setName("");
 171     // Retry, now there won't be a conflict.
 172     Constant *NewF = getOrInsertFunction(Name, Ty);
 173     F->setName(Name);
 174     return NewF;
 175   }
 176
 177   // If the function exists but has the wrong type, return a bitcast to the
 178   // right type.
 179   if (F->getType() != PointerType::getUnqual(Ty))
 180     return ConstantExpr::getBitCast(F, PointerType::getUnqual(Ty));
 181
 182   // Otherwise, we just found the existing function or a prototype.
 183   return F;
 184 }
 185
 186 Constant *Module::getOrInsertTargetIntrinsic(StringRef Name,
 187                                              const FunctionType *Ty,
 188                                              AttrListPtr AttributeList) {
 189   // See if we have a definition for the specified function already.
 190   GlobalValue *F = getNamedValue(Name);
 191   if (F == 0) {
 192     // Nope, add it
 193     Function *New = Function::Create(Ty, GlobalVariable::ExternalLinkage, Name);
 194     New->setAttributes(AttributeList);
 195     FunctionList.push_back(New);
 196     return New; // Return the new prototype.
 197   }
 198
 199   // Otherwise, we just found the existing function or a prototype.
 200   return F;
 201 }
 202
 203 Constant *Module::getOrInsertFunction(StringRef Name,
 204                                       const FunctionType *Ty) {
 205   AttrListPtr AttributeList = AttrListPtr::get((AttributeWithIndex *)0, 0);
 206   return getOrInsertFunction(Name, Ty, AttributeList);
 207 }
 208
 209 // getOrInsertFunction - Look up the specified function in the module symbol
 210 // table.  If it does not exist, add a prototype for the function and return it.
 211 // This version of the method takes a null terminated list of function
 212 // arguments, which makes it easier for clients to use.
 213 //
 214 Constant *Module::getOrInsertFunction(StringRef Name,
 215                                       AttrListPtr AttributeList,
 216                                       const Type *RetTy, ...) {
 217   va_list Args;
 218   va_start(Args, RetTy);
 219
 220   // Build the list of argument types...
 221   std::vector<const Type*> ArgTys;
 222   while (const Type *ArgTy = va_arg(Args, const Type*))
 223     ArgTys.push_back(ArgTy);
 224
 225   va_end(Args);
 226
 227   // Build the function type and chain to the other getOrInsertFunction...
 228   return getOrInsertFunction(Name,
 229                              FunctionType::get(RetTy, ArgTys, false),
 230                              AttributeList);
 231 }
 232
 233 Constant *Module::getOrInsertFunction(StringRef Name,
 234                                       const Type *RetTy, ...) {
 235   va_list Args;
 236   va_start(Args, RetTy);
 237
 238   // Build the list of argument types...
 239   std::vector<const Type*> ArgTys;
 240   while (const Type *ArgTy = va_arg(Args, const Type*))
 241     ArgTys.push_back(ArgTy);
 242
 243   va_end(Args);
 244
 245   // Build the function type and chain to the other getOrInsertFunction...
 246   return getOrInsertFunction(Name,
 247                              FunctionType::get(RetTy, ArgTys, false),
 248                              AttrListPtr::get((AttributeWithIndex *)0, 0));
 249 }
 250
 251 // getFunction - Look up the specified function in the module symbol table.
 252 // If it does not exist, return null.
 253 //
 254 Function *Module::getFunction(StringRef Name) const {
 255   return dyn_cast_or_null<Function>(getNamedValue(Name));
 256 }
 257
 258 //===----------------------------------------------------------------------===//
 259 // Methods for easy access to the global variables in the module.
 260 //
 261
 262 /// getGlobalVariable - Look up the specified global variable in the module
 263 /// symbol table.  If it does not exist, return null.  The type argument
 264 /// should be the underlying type of the global, i.e., it should not have
 265 /// the top-level PointerType, which represents the address of the global.
 266 /// If AllowLocal is set to true, this function will return types that
 267 /// have an local. By default, these types are not returned.
 268 ///
 269 GlobalVariable *Module::getGlobalVariable(StringRef Name,
 270                                           bool AllowLocal) const {
 271   if (GlobalVariable *Result =
 272       dyn_cast_or_null<GlobalVariable>(getNamedValue(Name)))
 273     if (AllowLocal || !Result->hasLocalLinkage())
 274       return Result;
 275   return 0;
 276 }
 277
 278 /// getOrInsertGlobal - Look up the specified global in the module symbol table.
 279 ///   1. If it does not exist, add a declaration of the global and return it.
 280 ///   2. Else, the global exists but has the wrong type: return the function
 281 ///      with a constantexpr cast to the right type.
 282 ///   3. Finally, if the existing global is the correct delclaration, return the
 283 ///      existing global.
 284 Constant *Module::getOrInsertGlobal(StringRef Name, const Type *Ty) {
 285   // See if we have a definition for the specified global already.
 286   GlobalVariable *GV = dyn_cast_or_null<GlobalVariable>(getNamedValue(Name));
 287   if (GV == 0) {
 288     // Nope, add it
 289     GlobalVariable *New =
 290       new GlobalVariable(*this, Ty, false, GlobalVariable::ExternalLinkage,
 291                          0, Name);
 292      return New;                    // Return the new declaration.
 293   }
 294
 295   // If the variable exists but has the wrong type, return a bitcast to the
 296   // right type.
 297   if (GV->getType() != PointerType::getUnqual(Ty))
 298     return ConstantExpr::getBitCast(GV, PointerType::getUnqual(Ty));
 299
 300   // Otherwise, we just found the existing function or a prototype.
 301   return GV;
 302 }
 303
 304 //===----------------------------------------------------------------------===//
 305 // Methods for easy access to the global variables in the module.
 306 //
 307
 308 // getNamedAlias - Look up the specified global in the module symbol table.
 309 // If it does not exist, return null.
 310 //
 311 GlobalAlias *Module::getNamedAlias(StringRef Name) const {
 312   return dyn_cast_or_null<GlobalAlias>(getNamedValue(Name));
 313 }
 314
 315 /// getNamedMetadata - Return the first NamedMDNode in the module with the
 316 /// specified name. This method returns null if a NamedMDNode with the
 317 /// specified name is not found.
 318 NamedMDNode *Module::getNamedMetadata(const Twine &Name) const {
 319   SmallString<256> NameData;
 320   StringRef NameRef = Name.toStringRef(NameData);
 321   return static_cast<StringMap<NamedMDNode*> *>(NamedMDSymTab)->lookup(NameRef);
 322 }
 323
 324 /// getOrInsertNamedMetadata - Return the first named MDNode in the module
 325 /// with the specified name. This method returns a new NamedMDNode if a
 326 /// NamedMDNode with the specified name is not found.
 327 NamedMDNode *Module::getOrInsertNamedMetadata(StringRef Name) {
 328   NamedMDNode *&NMD =
 329     (*static_cast<StringMap<NamedMDNode *> *>(NamedMDSymTab))[Name];
 330   if (!NMD) {
 331     NMD = new NamedMDNode(Name);
 332     NMD->setParent(this);
 333     NamedMDList.push_back(NMD);
 334   }
 335   return NMD;
 336 }
 337
 338 void Module::eraseNamedMetadata(NamedMDNode *NMD) {
 339   static_cast<StringMap<NamedMDNode *> *>(NamedMDSymTab)->erase(NMD->getName());
 340   NamedMDList.erase(NMD);
 341 }
 342
 343 //===----------------------------------------------------------------------===//
 344 // Methods for easy access to the types in the module.
 345 //
 346
 347
 348 // addTypeName - Insert an entry in the symbol table mapping Str to Type.  If
 349 // there is already an entry for this name, true is returned and the symbol
 350 // table is not modified.
 351 //
 352 bool Module::addTypeName(StringRef Name, const Type *Ty) {
 353   TypeSymbolTable &ST = getTypeSymbolTable();
 354
 355   if (ST.lookup(Name)) return true;  // Already in symtab...
 356
 357   // Not in symbol table?  Set the name with the Symtab as an argument so the
 358   // type knows what to update...
 359   ST.insert(Name, Ty);
 360
 361   return false;
 362 }
 363
 364 /// getTypeByName - Return the type with the specified name in this module, or
 365 /// null if there is none by that name.
 366 const Type *Module::getTypeByName(StringRef Name) const {
 367   const TypeSymbolTable &ST = getTypeSymbolTable();
 368   return cast_or_null<Type>(ST.lookup(Name));
 369 }
 370
 371 // getTypeName - If there is at least one entry in the symbol table for the
 372 // specified type, return it.
 373 //
 374 std::string Module::getTypeName(const Type *Ty) const {
 375   const TypeSymbolTable &ST = getTypeSymbolTable();
 376
 377   TypeSymbolTable::const_iterator TI = ST.begin();
 378   TypeSymbolTable::const_iterator TE = ST.end();
 379   if ( TI == TE ) return ""; // No names for types
 380
 381   while (TI != TE && TI->second != Ty)
 382     ++TI;
 383
 384   if (TI != TE)  // Must have found an entry!
 385     return TI->first;
 386   return "";     // Must not have found anything...
 387 }
 388
 389 //===----------------------------------------------------------------------===//
 390 // Methods to control the materialization of GlobalValues in the Module.
 391 //
 392 void Module::setMaterializer(GVMaterializer *GVM) {
 393   assert(!Materializer &&
 394          "Module already has a GVMaterializer.  Call MaterializeAllPermanently"
 395          " to clear it out before setting another one.");
 396   Materializer.reset(GVM);
 397 }
 398
 399 bool Module::isMaterializable(const GlobalValue *GV) const {
 400   if (Materializer)
 401     return Materializer->isMaterializable(GV);
 402   return false;
 403 }
 404
 405 bool Module::isDematerializable(const GlobalValue *GV) const {
 406   if (Materializer)
 407     return Materializer->isDematerializable(GV);
 408   return false;
 409 }
 410
 411 bool Module::Materialize(GlobalValue *GV, std::string *ErrInfo) {
 412   if (Materializer)
 413     return Materializer->Materialize(GV, ErrInfo);
 414   return false;
 415 }
 416
 417 void Module::Dematerialize(GlobalValue *GV) {
 418   if (Materializer)
 419     return Materializer->Dematerialize(GV);
 420 }
 421
 422 bool Module::MaterializeAll(std::string *ErrInfo) {
 423   if (!Materializer)
 424     return false;
 425   return Materializer->MaterializeModule(this, ErrInfo);
 426 }
 427
 428 bool Module::MaterializeAllPermanently(std::string *ErrInfo) {
 429   if (MaterializeAll(ErrInfo))
 430     return true;
 431   Materializer.reset();
 432   return false;
 433 }
 434
 435 //===----------------------------------------------------------------------===//
 436 // Other module related stuff.
 437 //
 438
 439
 440 // dropAllReferences() - This function causes all the subelementss to "let go"
 441 // of all references that they are maintaining.  This allows one to 'delete' a
 442 // whole module at a time, even though there may be circular references... first
 443 // all references are dropped, and all use counts go to zero.  Then everything
 444 // is deleted for real.  Note that no operations are valid on an object that
 445 // has "dropped all references", except operator delete.
 446 //
 447 void Module::dropAllReferences() {
 448   for(Module::iterator I = begin(), E = end(); I != E; ++I)
 449     I->dropAllReferences();
 450
 451   for(Module::global_iterator I = global_begin(), E = global_end(); I != E; ++I)
 452     I->dropAllReferences();
 453
 454   for(Module::alias_iterator I = alias_begin(), E = alias_end(); I != E; ++I)
 455     I->dropAllReferences();
 456 }
 457
 458 void Module::addLibrary(StringRef Lib) {
 459   for (Module::lib_iterator I = lib_begin(), E = lib_end(); I != E; ++I)
 460     if (*I == Lib)
 461       return;
 462   LibraryList.push_back(Lib);
 463 }
 464
 465 void Module::removeLibrary(StringRef Lib) {
 466   LibraryListType::iterator I = LibraryList.begin();
 467   LibraryListType::iterator E = LibraryList.end();
 468   for (;I != E; ++I)
 469     if (*I == Lib) {
 470       LibraryList.erase(I);
 471       return;
 472     }
 473 }