src/llvm/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/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   return getOrInsertFunction(Name, Ty, AttrListPtr());
 192 }
 193
 194 // getOrInsertFunction - Look up the specified function in the module symbol
 195 // table.  If it does not exist, add a prototype for the function and return it.
 196 // This version of the method takes a null terminated list of function
 197 // arguments, which makes it easier for clients to use.
 198 //
 199 Constant *Module::getOrInsertFunction(StringRef Name,
 200                                       AttrListPtr AttributeList,
 201                                       Type *RetTy, ...) {
 202   va_list Args;
 203   va_start(Args, RetTy);
 204
 205   // Build the list of argument types...
 206   std::vector<Type*> ArgTys;
 207   while (Type *ArgTy = va_arg(Args, Type*))
 208     ArgTys.push_back(ArgTy);
 209
 210   va_end(Args);
 211
 212   // Build the function type and chain to the other getOrInsertFunction...
 213   return getOrInsertFunction(Name,
 214                              FunctionType::get(RetTy, ArgTys, false),
 215                              AttributeList);
 216 }
 217
 218 Constant *Module::getOrInsertFunction(StringRef Name,
 219                                       Type *RetTy, ...) {
 220   va_list Args;
 221   va_start(Args, RetTy);
 222
 223   // Build the list of argument types...
 224   std::vector<Type*> ArgTys;
 225   while (Type *ArgTy = va_arg(Args, Type*))
 226     ArgTys.push_back(ArgTy);
 227
 228   va_end(Args);
 229
 230   // Build the function type and chain to the other getOrInsertFunction...
 231   return getOrInsertFunction(Name,
 232                              FunctionType::get(RetTy, ArgTys, false),
 233                              AttrListPtr());
 234 }
 235
 236 // getFunction - Look up the specified function in the module symbol table.
 237 // If it does not exist, return null.
 238 //
 239 Function *Module::getFunction(StringRef Name) const {
 240   return dyn_cast_or_null<Function>(getNamedValue(Name));
 241 }
 242
 243 //===----------------------------------------------------------------------===//
 244 // Methods for easy access to the global variables in the module.
 245 //
 246
 247 /// getGlobalVariable - Look up the specified global variable in the module
 248 /// symbol table.  If it does not exist, return null.  The type argument
 249 /// should be the underlying type of the global, i.e., it should not have
 250 /// the top-level PointerType, which represents the address of the global.
 251 /// If AllowLocal is set to true, this function will return types that
 252 /// have an local. By default, these types are not returned.
 253 ///
 254 GlobalVariable *Module::getGlobalVariable(StringRef Name,
 255                                           bool AllowLocal) const {
 256   if (GlobalVariable *Result =
 257       dyn_cast_or_null<GlobalVariable>(getNamedValue(Name)))
 258     if (AllowLocal || !Result->hasLocalLinkage())
 259       return Result;
 260   return 0;
 261 }
 262
 263 /// getOrInsertGlobal - Look up the specified global in the module symbol table.
 264 ///   1. If it does not exist, add a declaration of the global and return it.
 265 ///   2. Else, the global exists but has the wrong type: return the function
 266 ///      with a constantexpr cast to the right type.
 267 ///   3. Finally, if the existing global is the correct delclaration, return the
 268 ///      existing global.
 269 Constant *Module::getOrInsertGlobal(StringRef Name, Type *Ty) {
 270   // See if we have a definition for the specified global already.
 271   GlobalVariable *GV = dyn_cast_or_null<GlobalVariable>(getNamedValue(Name));
 272   if (GV == 0) {
 273     // Nope, add it
 274     GlobalVariable *New =
 275       new GlobalVariable(*this, Ty, false, GlobalVariable::ExternalLinkage,
 276                          0, Name);
 277      return New;                    // Return the new declaration.
 278   }
 279
 280   // If the variable exists but has the wrong type, return a bitcast to the
 281   // right type.
 282   if (GV->getType() != PointerType::getUnqual(Ty))
 283     return ConstantExpr::getBitCast(GV, PointerType::getUnqual(Ty));
 284
 285   // Otherwise, we just found the existing function or a prototype.
 286   return GV;
 287 }
 288
 289 //===----------------------------------------------------------------------===//
 290 // Methods for easy access to the global variables in the module.
 291 //
 292
 293 // getNamedAlias - Look up the specified global in the module symbol table.
 294 // If it does not exist, return null.
 295 //
 296 GlobalAlias *Module::getNamedAlias(StringRef Name) const {
 297   return dyn_cast_or_null<GlobalAlias>(getNamedValue(Name));
 298 }
 299
 300 /// getNamedMetadata - Return the first NamedMDNode in the module with the
 301 /// specified name. This method returns null if a NamedMDNode with the
 302 /// specified name is not found.
 303 NamedMDNode *Module::getNamedMetadata(const Twine &Name) const {
 304   SmallString<256> NameData;
 305   StringRef NameRef = Name.toStringRef(NameData);
 306   return static_cast<StringMap<NamedMDNode*> *>(NamedMDSymTab)->lookup(NameRef);
 307 }
 308
 309 /// getOrInsertNamedMetadata - Return the first named MDNode in the module
 310 /// with the specified name. This method returns a new NamedMDNode if a
 311 /// NamedMDNode with the specified name is not found.
 312 NamedMDNode *Module::getOrInsertNamedMetadata(StringRef Name) {
 313   NamedMDNode *&NMD =
 314     (*static_cast<StringMap<NamedMDNode *> *>(NamedMDSymTab))[Name];
 315   if (!NMD) {
 316     NMD = new NamedMDNode(Name);
 317     NMD->setParent(this);
 318     NamedMDList.push_back(NMD);
 319   }
 320   return NMD;
 321 }
 322
 323 /// eraseNamedMetadata - Remove the given NamedMDNode from this module and
 324 /// delete it.
 325 void Module::eraseNamedMetadata(NamedMDNode *NMD) {
 326   static_cast<StringMap<NamedMDNode *> *>(NamedMDSymTab)->erase(NMD->getName());
 327   NamedMDList.erase(NMD);
 328 }
 329
 330 /// getModuleFlagsMetadata - Returns the module flags in the provided vector.
 331 void Module::
 332 getModuleFlagsMetadata(SmallVectorImpl<ModuleFlagEntry> &Flags) const {
 333   const NamedMDNode *ModFlags = getModuleFlagsMetadata();
 334   if (!ModFlags) return;
 335
 336   for (unsigned i = 0, e = ModFlags->getNumOperands(); i != e; ++i) {
 337     MDNode *Flag = ModFlags->getOperand(i);
 338     ConstantInt *Behavior = cast<ConstantInt>(Flag->getOperand(0));
 339     MDString *Key = cast<MDString>(Flag->getOperand(1));
 340     Value *Val = Flag->getOperand(2);
 341     Flags.push_back(ModuleFlagEntry(ModFlagBehavior(Behavior->getZExtValue()),
 342                                     Key, Val));
 343   }
 344 }
 345
 346 /// getModuleFlagsMetadata - Returns the NamedMDNode in the module that
 347 /// represents module-level flags. This method returns null if there are no
 348 /// module-level flags.
 349 NamedMDNode *Module::getModuleFlagsMetadata() const {
 350   return getNamedMetadata("llvm.module.flags");
 351 }
 352
 353 /// getOrInsertModuleFlagsMetadata - Returns the NamedMDNode in the module that
 354 /// represents module-level flags. If module-level flags aren't found, it
 355 /// creates the named metadata that contains them.
 356 NamedMDNode *Module::getOrInsertModuleFlagsMetadata() {
 357   return getOrInsertNamedMetadata("llvm.module.flags");
 358 }
 359
 360 /// addModuleFlag - Add a module-level flag to the module-level flags
 361 /// metadata. It will create the module-level flags named metadata if it doesn't
 362 /// already exist.
 363 void Module::addModuleFlag(ModFlagBehavior Behavior, StringRef Key,
 364                            Value *Val) {
 365   Type *Int32Ty = Type::getInt32Ty(Context);
 366   Value *Ops[3] = {
 367     ConstantInt::get(Int32Ty, Behavior), MDString::get(Context, Key), Val
 368   };
 369   getOrInsertModuleFlagsMetadata()->addOperand(MDNode::get(Context, Ops));
 370 }
 371 void Module::addModuleFlag(ModFlagBehavior Behavior, StringRef Key,
 372                            uint32_t Val) {
 373   Type *Int32Ty = Type::getInt32Ty(Context);
 374   addModuleFlag(Behavior, Key, ConstantInt::get(Int32Ty, Val));
 375 }
 376 void Module::addModuleFlag(MDNode *Node) {
 377   assert(Node->getNumOperands() == 3 &&
 378          "Invalid number of operands for module flag!");
 379   assert(isa<ConstantInt>(Node->getOperand(0)) &&
 380          isa<MDString>(Node->getOperand(1)) &&
 381          "Invalid operand types for module flag!");
 382   getOrInsertModuleFlagsMetadata()->addOperand(Node);
 383 }
 384
 385 //===----------------------------------------------------------------------===//
 386 // Methods to control the materialization of GlobalValues in the Module.
 387 //
 388 void Module::setMaterializer(GVMaterializer *GVM) {
 389   assert(!Materializer &&
 390          "Module already has a GVMaterializer.  Call MaterializeAllPermanently"
 391          " to clear it out before setting another one.");
 392   Materializer.reset(GVM);
 393 }
 394
 395 bool Module::isMaterializable(const GlobalValue *GV) const {
 396   if (Materializer)
 397     return Materializer->isMaterializable(GV);
 398   return false;
 399 }
 400
 401 bool Module::isDematerializable(const GlobalValue *GV) const {
 402   if (Materializer)
 403     return Materializer->isDematerializable(GV);
 404   return false;
 405 }
 406
 407 bool Module::Materialize(GlobalValue *GV, std::string *ErrInfo) {
 408   if (Materializer)
 409     return Materializer->Materialize(GV, ErrInfo);
 410   return false;
 411 }
 412
 413 void Module::Dematerialize(GlobalValue *GV) {
 414   if (Materializer)
 415     return Materializer->Dematerialize(GV);
 416 }
 417
 418 bool Module::MaterializeAll(std::string *ErrInfo) {
 419   if (!Materializer)
 420     return false;
 421   return Materializer->MaterializeModule(this, ErrInfo);
 422 }
 423
 424 bool Module::MaterializeAllPermanently(std::string *ErrInfo) {
 425   if (MaterializeAll(ErrInfo))
 426     return true;
 427   Materializer.reset();
 428   return false;
 429 }
 430
 431 //===----------------------------------------------------------------------===//
 432 // Other module related stuff.
 433 //
 434
 435
 436 // dropAllReferences() - This function causes all the subelements to "let go"
 437 // of all references that they are maintaining.  This allows one to 'delete' a
 438 // whole module at a time, even though there may be circular references... first
 439 // all references are dropped, and all use counts go to zero.  Then everything
 440 // is deleted for real.  Note that no operations are valid on an object that
 441 // has "dropped all references", except operator delete.
 442 //
 443 void Module::dropAllReferences() {
 444   for(Module::iterator I = begin(), E = end(); I != E; ++I)
 445     I->dropAllReferences();
 446
 447   for(Module::global_iterator I = global_begin(), E = global_end(); I != E; ++I)
 448     I->dropAllReferences();
 449
 450   for(Module::alias_iterator I = alias_begin(), E = alias_end(); I != E; ++I)
 451     I->dropAllReferences();
 452 }
 453
 454 void Module::addLibrary(StringRef Lib) {
 455   for (Module::lib_iterator I = lib_begin(), E = lib_end(); I != E; ++I)
 456     if (*I == Lib)
 457       return;
 458   LibraryList.push_back(Lib);
 459 }
 460
 461 void Module::removeLibrary(StringRef Lib) {
 462   LibraryListType::iterator I = LibraryList.begin();
 463   LibraryListType::iterator E = LibraryList.end();
 464   for (;I != E; ++I)
 465     if (*I == Lib) {
 466       LibraryList.erase(I);
 467       return;
 468     }
 469 }