1 //===-- Function.cpp - Implement the Global object classes ----------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements the Function class for the VMCore library.
12 //===----------------------------------------------------------------------===//
14 #include "llvm/Module.h"
15 #include "llvm/DerivedTypes.h"
16 #include "llvm/IntrinsicInst.h"
17 #include "llvm/ParameterAttributes.h"
18 #include "llvm/CodeGen/ValueTypes.h"
19 #include "llvm/Support/LeakDetector.h"
20 #include "llvm/Support/StringPool.h"
21 #include "SymbolTableListTraitsImpl.h"
22 #include "llvm/ADT/BitVector.h"
23 #include "llvm/ADT/DenseMap.h"
24 #include "llvm/ADT/StringExtras.h"
27 BasicBlock *ilist_traits<BasicBlock>::createSentinel() {
28 BasicBlock *Ret = new BasicBlock();
29 // This should not be garbage monitored.
30 LeakDetector::removeGarbageObject(Ret);
34 iplist<BasicBlock> &ilist_traits<BasicBlock>::getList(Function *F) {
35 return F->getBasicBlockList();
38 Argument *ilist_traits<Argument>::createSentinel() {
39 Argument *Ret = new Argument(Type::Int32Ty);
40 // This should not be garbage monitored.
41 LeakDetector::removeGarbageObject(Ret);
45 iplist<Argument> &ilist_traits<Argument>::getList(Function *F) {
46 return F->getArgumentList();
49 // Explicit instantiations of SymbolTableListTraits since some of the methods
50 // are not in the public header file...
51 template class SymbolTableListTraits<Argument, Function>;
52 template class SymbolTableListTraits<BasicBlock, Function>;
54 //===----------------------------------------------------------------------===//
55 // Argument Implementation
56 //===----------------------------------------------------------------------===//
58 Argument::Argument(const Type *Ty, const std::string &Name, Function *Par)
59 : Value(Ty, Value::ArgumentVal) {
62 // Make sure that we get added to a function
63 LeakDetector::addGarbageObject(this);
66 Par->getArgumentList().push_back(this);
70 void Argument::setParent(Function *parent) {
72 LeakDetector::addGarbageObject(this);
75 LeakDetector::removeGarbageObject(this);
78 /// getArgNo - Return the index of this formal argument in its containing
79 /// function. For example in "void foo(int a, float b)" a is 0 and b is 1.
80 unsigned Argument::getArgNo() const {
81 const Function *F = getParent();
82 assert(F && "Argument is not in a function");
84 Function::const_arg_iterator AI = F->arg_begin();
86 for (; &*AI != this; ++AI)
92 /// hasByValAttr - Return true if this argument has the byval attribute on it
93 /// in its containing function.
94 bool Argument::hasByValAttr() const {
95 if (!isa<PointerType>(getType())) return false;
96 return getParent()->paramHasAttr(getArgNo()+1, ParamAttr::ByVal);
99 /// hasNoAliasAttr - Return true if this argument has the noalias attribute on
100 /// it in its containing function.
101 bool Argument::hasNoAliasAttr() const {
102 if (!isa<PointerType>(getType())) return false;
103 return getParent()->paramHasAttr(getArgNo()+1, ParamAttr::NoAlias);
106 /// hasSRetAttr - Return true if this argument has the sret attribute on
107 /// it in its containing function.
108 bool Argument::hasStructRetAttr() const {
109 if (!isa<PointerType>(getType())) return false;
110 return getParent()->paramHasAttr(getArgNo()+1, ParamAttr::StructRet);
116 //===----------------------------------------------------------------------===//
117 // Helper Methods in Function
118 //===----------------------------------------------------------------------===//
120 const FunctionType *Function::getFunctionType() const {
121 return cast<FunctionType>(getType()->getElementType());
124 bool Function::isVarArg() const {
125 return getFunctionType()->isVarArg();
128 const Type *Function::getReturnType() const {
129 return getFunctionType()->getReturnType();
132 void Function::removeFromParent() {
133 getParent()->getFunctionList().remove(this);
136 void Function::eraseFromParent() {
137 getParent()->getFunctionList().erase(this);
140 /// @brief Determine whether the function has the given attribute.
141 bool Function::paramHasAttr(uint16_t i, unsigned attr) const {
142 return ParamAttrs && ParamAttrs->paramHasAttr(i, (ParameterAttributes)attr);
145 /// @brief Determine if the function cannot return.
146 bool Function::doesNotReturn() const {
147 return paramHasAttr(0, ParamAttr::NoReturn);
150 /// @brief Determine if the function cannot unwind.
151 bool Function::doesNotThrow() const {
152 return paramHasAttr(0, ParamAttr::NoUnwind);
155 /// @brief Determine if the function does not access memory.
156 bool Function::doesNotAccessMemory() const {
157 return paramHasAttr(0, ParamAttr::ReadNone);
160 /// @brief Determine if the function does not access or only reads memory.
161 bool Function::onlyReadsMemory() const {
162 return doesNotAccessMemory() || paramHasAttr(0, ParamAttr::ReadOnly);
165 /// @brief Determine if the function returns a structure.
166 bool Function::isStructReturn() const {
167 return paramHasAttr(1, ParamAttr::StructRet);
170 //===----------------------------------------------------------------------===//
171 // Function Implementation
172 //===----------------------------------------------------------------------===//
174 Function::Function(const FunctionType *Ty, LinkageTypes Linkage,
175 const std::string &name, Module *ParentModule)
176 : GlobalValue(PointerType::getUnqual(Ty),
177 Value::FunctionVal, 0, 0, Linkage, name),
179 SymTab = new ValueSymbolTable();
181 assert((getReturnType()->isFirstClassType() ||getReturnType() == Type::VoidTy)
182 && "LLVM functions cannot return aggregate values!");
184 // If the function has arguments, mark them as lazily built.
185 if (Ty->getNumParams())
186 SubclassData = 1; // Set the "has lazy arguments" bit.
188 // Make sure that we get added to a function
189 LeakDetector::addGarbageObject(this);
192 ParentModule->getFunctionList().push_back(this);
195 Function::~Function() {
196 dropAllReferences(); // After this it is safe to delete instructions.
198 // Delete all of the method arguments and unlink from symbol table...
199 ArgumentList.clear();
202 // Drop our reference to the parameter attributes, if any.
204 ParamAttrs->dropRef();
206 // Remove the function from the on-the-side collector table.
210 void Function::BuildLazyArguments() const {
211 // Create the arguments vector, all arguments start out unnamed.
212 const FunctionType *FT = getFunctionType();
213 for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i) {
214 assert(FT->getParamType(i) != Type::VoidTy &&
215 "Cannot have void typed arguments!");
216 ArgumentList.push_back(new Argument(FT->getParamType(i)));
219 // Clear the lazy arguments bit.
220 const_cast<Function*>(this)->SubclassData &= ~1;
223 size_t Function::arg_size() const {
224 return getFunctionType()->getNumParams();
226 bool Function::arg_empty() const {
227 return getFunctionType()->getNumParams() == 0;
230 void Function::setParent(Module *parent) {
232 LeakDetector::addGarbageObject(this);
235 LeakDetector::removeGarbageObject(this);
238 void Function::setParamAttrs(const ParamAttrsList *attrs) {
239 // Avoid deleting the ParamAttrsList if they are setting the
240 // attributes to the same list.
241 if (ParamAttrs == attrs)
244 // Drop reference on the old ParamAttrsList
246 ParamAttrs->dropRef();
248 // Add reference to the new ParamAttrsList
252 // Set the new ParamAttrsList.
256 // dropAllReferences() - This function causes all the subinstructions to "let
257 // go" of all references that they are maintaining. This allows one to
258 // 'delete' a whole class at a time, even though there may be circular
259 // references... first all references are dropped, and all use counts go to
260 // zero. Then everything is deleted for real. Note that no operations are
261 // valid on an object that has "dropped all references", except operator
264 void Function::dropAllReferences() {
265 for (iterator I = begin(), E = end(); I != E; ++I)
266 I->dropAllReferences();
267 BasicBlocks.clear(); // Delete all basic blocks...
270 // Maintain the collector name for each function in an on-the-side table. This
271 // saves allocating an additional word in Function for programs which do not use
272 // GC (i.e., most programs) at the cost of increased overhead for clients which
274 static DenseMap<const Function*,PooledStringPtr> *CollectorNames;
275 static StringPool *CollectorNamePool;
277 bool Function::hasCollector() const {
278 return CollectorNames && CollectorNames->count(this);
281 const char *Function::getCollector() const {
282 assert(hasCollector() && "Function has no collector");
283 return *(*CollectorNames)[this];
286 void Function::setCollector(const char *Str) {
287 if (!CollectorNamePool)
288 CollectorNamePool = new StringPool();
290 CollectorNames = new DenseMap<const Function*,PooledStringPtr>();
291 (*CollectorNames)[this] = CollectorNamePool->intern(Str);
294 void Function::clearCollector() {
295 if (CollectorNames) {
296 CollectorNames->erase(this);
297 if (CollectorNames->empty()) {
298 delete CollectorNames;
300 if (CollectorNamePool->empty()) {
301 delete CollectorNamePool;
302 CollectorNamePool = 0;
308 /// getIntrinsicID - This method returns the ID number of the specified
309 /// function, or Intrinsic::not_intrinsic if the function is not an
310 /// intrinsic, or if the pointer is null. This value is always defined to be
311 /// zero to allow easy checking for whether a function is intrinsic or not. The
312 /// particular intrinsic functions which correspond to this value are defined in
313 /// llvm/Intrinsics.h.
315 unsigned Function::getIntrinsicID(bool noAssert) const {
316 const ValueName *ValName = this->getValueName();
319 unsigned Len = ValName->getKeyLength();
320 const char *Name = ValName->getKeyData();
322 if (Len < 5 || Name[4] != '.' || Name[0] != 'l' || Name[1] != 'l'
323 || Name[2] != 'v' || Name[3] != 'm')
324 return 0; // All intrinsics start with 'llvm.'
326 assert((Len != 5 || noAssert) && "'llvm.' is an invalid intrinsic name!");
328 #define GET_FUNCTION_RECOGNIZER
329 #include "llvm/Intrinsics.gen"
330 #undef GET_FUNCTION_RECOGNIZER
331 assert(noAssert && "Invalid LLVM intrinsic name");
335 std::string Intrinsic::getName(ID id, const Type **Tys, unsigned numTys) {
336 assert(id < num_intrinsics && "Invalid intrinsic ID!");
337 const char * const Table[] = {
339 #define GET_INTRINSIC_NAME_TABLE
340 #include "llvm/Intrinsics.gen"
341 #undef GET_INTRINSIC_NAME_TABLE
345 std::string Result(Table[id]);
346 for (unsigned i = 0; i < numTys; ++i)
348 Result += "." + MVT::getValueTypeString(MVT::getValueType(Tys[i]));
352 const FunctionType *Intrinsic::getType(ID id, const Type **Tys,
354 const Type *ResultTy = NULL;
355 std::vector<const Type*> ArgTys;
356 bool IsVarArg = false;
358 #define GET_INTRINSIC_GENERATOR
359 #include "llvm/Intrinsics.gen"
360 #undef GET_INTRINSIC_GENERATOR
362 return FunctionType::get(ResultTy, ArgTys, IsVarArg);
365 const ParamAttrsList *Intrinsic::getParamAttrs(ID id) {
366 ParamAttrsVector Attrs;
367 uint16_t Attr = ParamAttr::None;
369 #define GET_INTRINSIC_ATTRIBUTES
370 #include "llvm/Intrinsics.gen"
371 #undef GET_INTRINSIC_ATTRIBUTES
373 // Intrinsics cannot throw exceptions.
374 Attr |= ParamAttr::NoUnwind;
376 Attrs.push_back(ParamAttrsWithIndex::get(0, Attr));
377 return ParamAttrsList::get(Attrs);
380 Function *Intrinsic::getDeclaration(Module *M, ID id, const Type **Tys,
382 // There can never be multiple globals with the same name of different types,
383 // because intrinsics must be a specific type.
385 cast<Function>(M->getOrInsertFunction(getName(id, Tys, numTys),
386 getType(id, Tys, numTys)));
387 F->setParamAttrs(getParamAttrs(id));
391 Value *IntrinsicInst::StripPointerCasts(Value *Ptr) {
392 if (ConstantExpr *CE = dyn_cast<ConstantExpr>(Ptr)) {
393 if (CE->getOpcode() == Instruction::BitCast) {
394 if (isa<PointerType>(CE->getOperand(0)->getType()))
395 return StripPointerCasts(CE->getOperand(0));
396 } else if (CE->getOpcode() == Instruction::GetElementPtr) {
397 for (unsigned i = 1, e = CE->getNumOperands(); i != e; ++i)
398 if (!CE->getOperand(i)->isNullValue())
400 return StripPointerCasts(CE->getOperand(0));
405 if (BitCastInst *CI = dyn_cast<BitCastInst>(Ptr)) {
406 if (isa<PointerType>(CI->getOperand(0)->getType()))
407 return StripPointerCasts(CI->getOperand(0));
408 } else if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(Ptr)) {
409 if (GEP->hasAllZeroIndices())
410 return StripPointerCasts(GEP->getOperand(0));