lib/VMCore/Function.cpp

   1 //===-- Function.cpp - Implement the Global object classes ----------------===//
   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 Function class for the VMCore library.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "llvm/Module.h"
  15 #include "llvm/DerivedTypes.h"
  16 #include "llvm/IntrinsicInst.h"
  17 #include "llvm/CodeGen/ValueTypes.h"
  18 #include "llvm/Support/LeakDetector.h"
  19 #include "llvm/Support/StringPool.h"
  20 #include "SymbolTableListTraitsImpl.h"
  21 #include "llvm/ADT/DenseMap.h"
  22 #include "llvm/ADT/StringExtras.h"
  23 using namespace llvm;
  24
  25
  26 // Explicit instantiations of SymbolTableListTraits since some of the methods
  27 // are not in the public header file...
  28 template class SymbolTableListTraits<Argument, Function>;
  29 template class SymbolTableListTraits<BasicBlock, Function>;
  30
  31 //===----------------------------------------------------------------------===//
  32 // Argument Implementation
  33 //===----------------------------------------------------------------------===//
  34
  35 Argument::Argument(const Type *Ty, const std::string &Name, Function *Par)
  36   : Value(Ty, Value::ArgumentVal) {
  37   Parent = 0;
  38
  39   // Make sure that we get added to a function
  40   LeakDetector::addGarbageObject(this);
  41
  42   if (Par)
  43     Par->getArgumentList().push_back(this);
  44   setName(Name);
  45 }
  46
  47 void Argument::setParent(Function *parent) {
  48   if (getParent())
  49     LeakDetector::addGarbageObject(this);
  50   Parent = parent;
  51   if (getParent())
  52     LeakDetector::removeGarbageObject(this);
  53 }
  54
  55 /// getArgNo - Return the index of this formal argument in its containing
  56 /// function.  For example in "void foo(int a, float b)" a is 0 and b is 1.
  57 unsigned Argument::getArgNo() const {
  58   const Function *F = getParent();
  59   assert(F && "Argument is not in a function");
  60
  61   Function::const_arg_iterator AI = F->arg_begin();
  62   unsigned ArgIdx = 0;
  63   for (; &*AI != this; ++AI)
  64     ++ArgIdx;
  65
  66   return ArgIdx;
  67 }
  68
  69 /// hasByValAttr - Return true if this argument has the byval attribute on it
  70 /// in its containing function.
  71 bool Argument::hasByValAttr() const {
  72   if (!isa<PointerType>(getType())) return false;
  73   return getParent()->paramHasAttr(getArgNo()+1, Attribute::ByVal);
  74 }
  75
  76 /// hasNoAliasAttr - Return true if this argument has the noalias attribute on
  77 /// it in its containing function.
  78 bool Argument::hasNoAliasAttr() const {
  79   if (!isa<PointerType>(getType())) return false;
  80   return getParent()->paramHasAttr(getArgNo()+1, Attribute::NoAlias);
  81 }
  82
  83 /// hasNoCaptureAttr - Return true if this argument has the nocapture attribute
  84 /// on it in its containing function.
  85 bool Argument::hasNoCaptureAttr() const {
  86   if (!isa<PointerType>(getType())) return false;
  87   return getParent()->paramHasAttr(getArgNo()+1, Attribute::NoCapture);
  88 }
  89
  90 /// hasSRetAttr - Return true if this argument has the sret attribute on
  91 /// it in its containing function.
  92 bool Argument::hasStructRetAttr() const {
  93   if (!isa<PointerType>(getType())) return false;
  94   if (this != getParent()->arg_begin())
  95     return false; // StructRet param must be first param
  96   return getParent()->paramHasAttr(1, Attribute::StructRet);
  97 }
  98
  99 /// addAttr - Add a Attribute to an argument
 100 void Argument::addAttr(Attributes attr) {
 101   getParent()->addAttribute(getArgNo() + 1, attr);
 102 }
 103
 104 /// removeAttr - Remove a Attribute from an argument
 105 void Argument::removeAttr(Attributes attr) {
 106   getParent()->removeAttribute(getArgNo() + 1, attr);
 107 }
 108
 109
 110 //===----------------------------------------------------------------------===//
 111 // Helper Methods in Function
 112 //===----------------------------------------------------------------------===//
 113
 114 const FunctionType *Function::getFunctionType() const {
 115   return cast<FunctionType>(getType()->getElementType());
 116 }
 117
 118 bool Function::isVarArg() const {
 119   return getFunctionType()->isVarArg();
 120 }
 121
 122 const Type *Function::getReturnType() const {
 123   return getFunctionType()->getReturnType();
 124 }
 125
 126 void Function::removeFromParent() {
 127   getParent()->getFunctionList().remove(this);
 128 }
 129
 130 void Function::eraseFromParent() {
 131   getParent()->getFunctionList().erase(this);
 132 }
 133
 134 //===----------------------------------------------------------------------===//
 135 // Function Implementation
 136 //===----------------------------------------------------------------------===//
 137
 138 Function::Function(const FunctionType *Ty, LinkageTypes Linkage,
 139                    const std::string &name, Module *ParentModule)
 140   : GlobalValue(PointerType::getUnqual(Ty),
 141                 Value::FunctionVal, 0, 0, Linkage, name) {
 142   assert(FunctionType::isValidReturnType(getReturnType()) &&
 143          !isa<OpaqueType>(getReturnType()) && "invalid return type");
 144   SymTab = new ValueSymbolTable();
 145
 146   // If the function has arguments, mark them as lazily built.
 147   if (Ty->getNumParams())
 148     SubclassData = 1;   // Set the "has lazy arguments" bit.
 149
 150   // Make sure that we get added to a function
 151   LeakDetector::addGarbageObject(this);
 152
 153   if (ParentModule)
 154     ParentModule->getFunctionList().push_back(this);
 155
 156   // Ensure intrinsics have the right parameter attributes.
 157   if (unsigned IID = getIntrinsicID())
 158     setAttributes(Intrinsic::getAttributes(Intrinsic::ID(IID)));
 159
 160 }
 161
 162 Function::~Function() {
 163   dropAllReferences();    // After this it is safe to delete instructions.
 164
 165   // Delete all of the method arguments and unlink from symbol table...
 166   ArgumentList.clear();
 167   delete SymTab;
 168
 169   // Remove the function from the on-the-side GC table.
 170   clearGC();
 171 }
 172
 173 void Function::BuildLazyArguments() const {
 174   // Create the arguments vector, all arguments start out unnamed.
 175   const FunctionType *FT = getFunctionType();
 176   for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i) {
 177     assert(FT->getParamType(i) != Type::VoidTy &&
 178            "Cannot have void typed arguments!");
 179     ArgumentList.push_back(new Argument(FT->getParamType(i)));
 180   }
 181
 182   // Clear the lazy arguments bit.
 183   const_cast<Function*>(this)->SubclassData &= ~1;
 184 }
 185
 186 size_t Function::arg_size() const {
 187   return getFunctionType()->getNumParams();
 188 }
 189 bool Function::arg_empty() const {
 190   return getFunctionType()->getNumParams() == 0;
 191 }
 192
 193 void Function::setParent(Module *parent) {
 194   if (getParent())
 195     LeakDetector::addGarbageObject(this);
 196   Parent = parent;
 197   if (getParent())
 198     LeakDetector::removeGarbageObject(this);
 199 }
 200
 201 // dropAllReferences() - This function causes all the subinstructions to "let
 202 // go" of all references that they are maintaining.  This allows one to
 203 // 'delete' a whole class at a time, even though there may be circular
 204 // references... first all references are dropped, and all use counts go to
 205 // zero.  Then everything is deleted for real.  Note that no operations are
 206 // valid on an object that has "dropped all references", except operator
 207 // delete.
 208 //
 209 void Function::dropAllReferences() {
 210   for (iterator I = begin(), E = end(); I != E; ++I)
 211     I->dropAllReferences();
 212   BasicBlocks.clear();    // Delete all basic blocks...
 213 }
 214
 215 void Function::addAttribute(unsigned i, Attributes attr) {
 216   AttrListPtr PAL = getAttributes();
 217   PAL = PAL.addAttr(i, attr);
 218   setAttributes(PAL);
 219 }
 220
 221 void Function::removeAttribute(unsigned i, Attributes attr) {
 222   AttrListPtr PAL = getAttributes();
 223   PAL = PAL.removeAttr(i, attr);
 224   setAttributes(PAL);
 225 }
 226
 227 // Maintain the GC name for each function in an on-the-side table. This saves
 228 // allocating an additional word in Function for programs which do not use GC
 229 // (i.e., most programs) at the cost of increased overhead for clients which do
 230 // use GC.
 231 static DenseMap<const Function*,PooledStringPtr> *GCNames;
 232 static StringPool *GCNamePool;
 233
 234 bool Function::hasGC() const {
 235   return GCNames && GCNames->count(this);
 236 }
 237
 238 const char *Function::getGC() const {
 239   assert(hasGC() && "Function has no collector");
 240   return *(*GCNames)[this];
 241 }
 242
 243 void Function::setGC(const char *Str) {
 244   if (!GCNamePool)
 245     GCNamePool = new StringPool();
 246   if (!GCNames)
 247     GCNames = new DenseMap<const Function*,PooledStringPtr>();
 248   (*GCNames)[this] = GCNamePool->intern(Str);
 249 }
 250
 251 void Function::clearGC() {
 252   if (GCNames) {
 253     GCNames->erase(this);
 254     if (GCNames->empty()) {
 255       delete GCNames;
 256       GCNames = 0;
 257       if (GCNamePool->empty()) {
 258         delete GCNamePool;
 259         GCNamePool = 0;
 260       }
 261     }
 262   }
 263 }
 264
 265 /// copyAttributesFrom - copy all additional attributes (those not needed to
 266 /// create a Function) from the Function Src to this one.
 267 void Function::copyAttributesFrom(const GlobalValue *Src) {
 268   assert(isa<Function>(Src) && "Expected a Function!");
 269   GlobalValue::copyAttributesFrom(Src);
 270   const Function *SrcF = cast<Function>(Src);
 271   setCallingConv(SrcF->getCallingConv());
 272   setAttributes(SrcF->getAttributes());
 273   if (SrcF->hasGC())
 274     setGC(SrcF->getGC());
 275   else
 276     clearGC();
 277 }
 278
 279 /// getIntrinsicID - This method returns the ID number of the specified
 280 /// function, or Intrinsic::not_intrinsic if the function is not an
 281 /// intrinsic, or if the pointer is null.  This value is always defined to be
 282 /// zero to allow easy checking for whether a function is intrinsic or not.  The
 283 /// particular intrinsic functions which correspond to this value are defined in
 284 /// llvm/Intrinsics.h.
 285 ///
 286 unsigned Function::getIntrinsicID() const {
 287   const ValueName *ValName = this->getValueName();
 288   if (!ValName)
 289     return 0;
 290   unsigned Len = ValName->getKeyLength();
 291   const char *Name = ValName->getKeyData();
 292
 293   if (Len < 5 || Name[4] != '.' || Name[0] != 'l' || Name[1] != 'l'
 294       || Name[2] != 'v' || Name[3] != 'm')
 295     return 0;  // All intrinsics start with 'llvm.'
 296
 297 #define GET_FUNCTION_RECOGNIZER
 298 #include "llvm/Intrinsics.gen"
 299 #undef GET_FUNCTION_RECOGNIZER
 300   return 0;
 301 }
 302
 303 std::string Intrinsic::getName(ID id, const Type **Tys, unsigned numTys) {
 304   assert(id < num_intrinsics && "Invalid intrinsic ID!");
 305   const char * const Table[] = {
 306     "not_intrinsic",
 307 #define GET_INTRINSIC_NAME_TABLE
 308 #include "llvm/Intrinsics.gen"
 309 #undef GET_INTRINSIC_NAME_TABLE
 310   };
 311   if (numTys == 0)
 312     return Table[id];
 313   std::string Result(Table[id]);
 314   for (unsigned i = 0; i < numTys; ++i) {
 315     if (const PointerType* PTyp = dyn_cast<PointerType>(Tys[i])) {
 316       Result += ".p" + llvm::utostr(PTyp->getAddressSpace()) +
 317                 MVT::getMVT(PTyp->getElementType()).getMVTString();
 318     }
 319     else if (Tys[i])
 320       Result += "." + MVT::getMVT(Tys[i]).getMVTString();
 321   }
 322   return Result;
 323 }
 324
 325 const FunctionType *Intrinsic::getType(ID id, const Type **Tys,
 326                                        unsigned numTys) {
 327   const Type *ResultTy = NULL;
 328   std::vector<const Type*> ArgTys;
 329   bool IsVarArg = false;
 330
 331 #define GET_INTRINSIC_GENERATOR
 332 #include "llvm/Intrinsics.gen"
 333 #undef GET_INTRINSIC_GENERATOR
 334
 335   return FunctionType::get(ResultTy, ArgTys, IsVarArg);
 336 }
 337
 338 bool Intrinsic::isOverloaded(ID id) {
 339   const bool OTable[] = {
 340     false,
 341 #define GET_INTRINSIC_OVERLOAD_TABLE
 342 #include "llvm/Intrinsics.gen"
 343 #undef GET_INTRINSIC_OVERLOAD_TABLE
 344   };
 345   return OTable[id];
 346 }
 347
 348 /// This defines the "Intrinsic::getAttributes(ID id)" method.
 349 #define GET_INTRINSIC_ATTRIBUTES
 350 #include "llvm/Intrinsics.gen"
 351 #undef GET_INTRINSIC_ATTRIBUTES
 352
 353 Function *Intrinsic::getDeclaration(Module *M, ID id, const Type **Tys,
 354                                     unsigned numTys) {
 355   // There can never be multiple globals with the same name of different types,
 356   // because intrinsics must be a specific type.
 357   return
 358     cast<Function>(M->getOrInsertFunction(getName(id, Tys, numTys),
 359                                           getType(id, Tys, numTys)));
 360 }
 361
 362 // This defines the "Intrinsic::getIntrinsicForGCCBuiltin()" method.
 363 #define GET_LLVM_INTRINSIC_FOR_GCC_BUILTIN
 364 #include "llvm/Intrinsics.gen"
 365 #undef GET_LLVM_INTRINSIC_FOR_GCC_BUILTIN
 366
 367 // vim: sw=2 ai