| //===-- SymbolTable.cpp - Implement the SymbolTable class -----------------===// |
| // |
| // This file implements the SymbolTable class for the VMCore library. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "llvm/SymbolTable.h" |
| #include "llvm/DerivedTypes.h" |
| #include "llvm/Module.h" |
| #include "Support/StringExtras.h" |
| #include <algorithm> |
| |
| #define DEBUG_SYMBOL_TABLE 0 |
| #define DEBUG_ABSTYPE 0 |
| |
| SymbolTable::~SymbolTable() { |
| // Drop all abstract type references in the type plane... |
| iterator TyPlane = find(Type::TypeTy); |
| if (TyPlane != end()) { |
| VarMap &TyP = TyPlane->second; |
| for (VarMap::iterator I = TyP.begin(), E = TyP.end(); I != E; ++I) { |
| const Type *Ty = cast<Type>(I->second); |
| if (Ty->isAbstract()) // If abstract, drop the reference... |
| cast<DerivedType>(Ty)->removeAbstractTypeUser(this); |
| } |
| } |
| |
| // TODO: FIXME: BIG ONE: This doesn't unreference abstract types for the planes |
| // that could still have entries! |
| |
| #ifndef NDEBUG // Only do this in -g mode... |
| bool LeftoverValues = true; |
| for (iterator i = begin(); i != end(); ++i) { |
| for (type_iterator I = i->second.begin(); I != i->second.end(); ++I) |
| if (!isa<Constant>(I->second) && !isa<Type>(I->second)) { |
| std::cerr << "Value still in symbol table! Type = '" |
| << i->first->getDescription() << "' Name = '" |
| << I->first << "'\n"; |
| LeftoverValues = false; |
| } |
| } |
| |
| assert(LeftoverValues && "Values remain in symbol table!"); |
| #endif |
| } |
| |
| // getUniqueName - Given a base name, return a string that is either equal to |
| // it (or derived from it) that does not already occur in the symbol table for |
| // the specified type. |
| // |
| std::string SymbolTable::getUniqueName(const Type *Ty, |
| const std::string &BaseName) { |
| iterator I = find(Ty); |
| if (I == end()) return BaseName; |
| |
| std::string TryName = BaseName; |
| unsigned Counter = 0; |
| type_iterator End = I->second.end(); |
| |
| while (I->second.find(TryName) != End) // Loop until we find unoccupied |
| TryName = BaseName + utostr(++Counter); // Name in the symbol table |
| return TryName; |
| } |
| |
| |
| |
| // lookup - Returns null on failure... |
| Value *SymbolTable::lookup(const Type *Ty, const std::string &Name) { |
| iterator I = find(Ty); |
| if (I != end()) { // We have symbols in that plane... |
| type_iterator J = I->second.find(Name); |
| if (J != I->second.end()) // and the name is in our hash table... |
| return J->second; |
| } |
| |
| return 0; |
| } |
| |
| void SymbolTable::remove(Value *N) { |
| assert(N->hasName() && "Value doesn't have name!"); |
| if (InternallyInconsistent) return; |
| |
| iterator I = find(N->getType()); |
| assert(I != end() && |
| "Trying to remove a type that doesn't have a plane yet!"); |
| removeEntry(I, I->second.find(N->getName())); |
| } |
| |
| // removeEntry - Remove a value from the symbol table... |
| // |
| Value *SymbolTable::removeEntry(iterator Plane, type_iterator Entry) { |
| if (InternallyInconsistent) return 0; |
| assert(Plane != super::end() && |
| Entry != Plane->second.end() && "Invalid entry to remove!"); |
| |
| Value *Result = Entry->second; |
| const Type *Ty = Result->getType(); |
| #if DEBUG_SYMBOL_TABLE |
| dump(); |
| std::cerr << " Removing Value: " << Result->getName() << "\n"; |
| #endif |
| |
| // Remove the value from the plane... |
| Plane->second.erase(Entry); |
| |
| // If the plane is empty, remove it now! |
| if (Plane->second.empty()) { |
| // If the plane represented an abstract type that we were interested in, |
| // unlink ourselves from this plane. |
| // |
| if (Plane->first->isAbstract()) { |
| #if DEBUG_ABSTYPE |
| std::cerr << "Plane Empty: Removing type: " |
| << Plane->first->getDescription() << "\n"; |
| #endif |
| cast<DerivedType>(Plane->first)->removeAbstractTypeUser(this); |
| } |
| |
| erase(Plane); |
| } |
| |
| // If we are removing an abstract type, remove the symbol table from it's use |
| // list... |
| if (Ty == Type::TypeTy) { |
| const Type *T = cast<Type>(Result); |
| if (T->isAbstract()) { |
| #if DEBUG_ABSTYPE |
| std::cerr << "Removing abs type from symtab" << T->getDescription()<<"\n"; |
| #endif |
| cast<DerivedType>(T)->removeAbstractTypeUser(this); |
| } |
| } |
| |
| return Result; |
| } |
| |
| // insertEntry - Insert a value into the symbol table with the specified |
| // name... |
| // |
| void SymbolTable::insertEntry(const std::string &Name, const Type *VTy, |
| Value *V) { |
| |
| // Check to see if there is a naming conflict. If so, rename this value! |
| if (lookup(VTy, Name)) { |
| std::string UniqueName = getUniqueName(VTy, Name); |
| assert(InternallyInconsistent == false && "Infinite loop inserting entry!"); |
| InternallyInconsistent = true; |
| V->setName(UniqueName, this); |
| InternallyInconsistent = false; |
| return; |
| } |
| |
| #if DEBUG_SYMBOL_TABLE |
| dump(); |
| std::cerr << " Inserting definition: " << Name << ": " |
| << VTy->getDescription() << "\n"; |
| #endif |
| |
| iterator I = find(VTy); |
| if (I == end()) { // Not in collection yet... insert dummy entry |
| // Insert a new empty element. I points to the new elements. |
| I = super::insert(make_pair(VTy, VarMap())).first; |
| assert(I != end() && "How did insert fail?"); |
| |
| // Check to see if the type is abstract. If so, it might be refined in the |
| // future, which would cause the plane of the old type to get merged into |
| // a new type plane. |
| // |
| if (VTy->isAbstract()) { |
| cast<DerivedType>(VTy)->addAbstractTypeUser(this); |
| #if DEBUG_ABSTYPE |
| std::cerr << "Added abstract type value: " << VTy->getDescription() |
| << "\n"; |
| #endif |
| } |
| } |
| |
| I->second.insert(make_pair(Name, V)); |
| |
| // If we are adding an abstract type, add the symbol table to it's use list. |
| if (VTy == Type::TypeTy) { |
| const Type *T = cast<Type>(V); |
| if (T->isAbstract()) { |
| cast<DerivedType>(T)->addAbstractTypeUser(this); |
| #if DEBUG_ABSTYPE |
| std::cerr << "Added abstract type to ST: " << T->getDescription() << "\n"; |
| #endif |
| } |
| } |
| } |
| |
| // This function is called when one of the types in the type plane are refined |
| void SymbolTable::refineAbstractType(const DerivedType *OldType, |
| const Type *NewType) { |
| // Search to see if we have any values of the type oldtype. If so, we need to |
| // move them into the newtype plane... |
| iterator TPI = find(OldType); |
| if (TPI != end()) { |
| // Get a handle to the new type plane... |
| iterator NewTypeIt = find(NewType); |
| if (NewTypeIt == super::end()) { // If no plane exists, add one |
| NewTypeIt = super::insert(make_pair(NewType, VarMap())).first; |
| |
| if (NewType->isAbstract()) { |
| cast<DerivedType>(NewType)->addAbstractTypeUser(this); |
| #if DEBUG_ABSTYPE |
| std::cerr << "[Added] refined to abstype: " << NewType->getDescription() |
| << "\n"; |
| #endif |
| } |
| } |
| |
| VarMap &NewPlane = NewTypeIt->second; |
| VarMap &OldPlane = TPI->second; |
| while (!OldPlane.empty()) { |
| std::pair<const std::string, Value*> V = *OldPlane.begin(); |
| |
| // Check to see if there is already a value in the symbol table that this |
| // would collide with. |
| type_iterator TI = NewPlane.find(V.first); |
| if (TI != NewPlane.end() && TI->second == V.second) { |
| // No action |
| |
| } else if (TI != NewPlane.end()) { |
| // The only thing we are allowing for now is two external global values |
| // folded into one. |
| // |
| GlobalValue *ExistGV = dyn_cast<GlobalValue>(TI->second); |
| GlobalValue *NewGV = dyn_cast<GlobalValue>(V.second); |
| |
| if (ExistGV && NewGV) { |
| assert((ExistGV->isExternal() || NewGV->isExternal()) && |
| "Two planes folded together with overlapping value names!"); |
| |
| // Make sure that ExistGV is the one we want to keep! |
| if (!NewGV->isExternal()) |
| std::swap(NewGV, ExistGV); |
| |
| // Ok we have two external global values. Make all uses of the new |
| // one use the old one... |
| NewGV->uncheckedReplaceAllUsesWith(ExistGV); |
| |
| // Now we just convert it to an unnamed method... which won't get |
| // added to our symbol table. The problem is that if we call |
| // setName on the method that it will try to remove itself from |
| // the symbol table and die... because it's not in the symtab |
| // right now. To fix this, we have an internally consistent flag |
| // that turns remove into a noop. Thus the name will get null'd |
| // out, but the symbol table won't get upset. |
| // |
| assert(InternallyInconsistent == false && |
| "Symbol table already inconsistent!"); |
| InternallyInconsistent = true; |
| |
| // Remove newM from the symtab |
| NewGV->setName(""); |
| InternallyInconsistent = false; |
| |
| // Now we can remove this global from the module entirely... |
| Module *M = NewGV->getParent(); |
| if (Function *F = dyn_cast<Function>(NewGV)) |
| M->getFunctionList().remove(F); |
| else |
| M->getGlobalList().remove(cast<GlobalVariable>(NewGV)); |
| delete NewGV; |
| } |
| } else { |
| insertEntry(V.first, NewType, V.second); |
| |
| } |
| // Remove the item from the old type plane |
| OldPlane.erase(OldPlane.begin()); |
| } |
| |
| // Ok, now we are not referencing the type anymore... take me off your user |
| // list please! |
| #if DEBUG_ABSTYPE |
| std::cerr << "Removing type " << OldType->getDescription() << "\n"; |
| #endif |
| OldType->removeAbstractTypeUser(this); |
| |
| // Remove the plane that is no longer used |
| erase(TPI); |
| } |
| |
| TPI = find(Type::TypeTy); |
| if (TPI != end()) { |
| // Loop over all of the types in the symbol table, replacing any references |
| // to OldType with references to NewType. Note that there may be multiple |
| // occurrences, and although we only need to remove one at a time, it's |
| // faster to remove them all in one pass. |
| // |
| VarMap &TyPlane = TPI->second; |
| for (VarMap::iterator I = TyPlane.begin(), E = TyPlane.end(); I != E; ++I) |
| if (I->second == (Value*)OldType) { // FIXME when Types aren't const. |
| #if DEBUG_ABSTYPE |
| std::cerr << "Removing type " << OldType->getDescription() << "\n"; |
| #endif |
| OldType->removeAbstractTypeUser(this); |
| |
| I->second = (Value*)NewType; // TODO FIXME when types aren't const |
| if (NewType->isAbstract()) { |
| #if DEBUG_ABSTYPE |
| std::cerr << "Added type " << NewType->getDescription() << "\n"; |
| #endif |
| cast<DerivedType>(NewType)->addAbstractTypeUser(this); |
| } |
| } |
| } |
| } |
| |
| void SymbolTable::typeBecameConcrete(const DerivedType *AbsTy) { |
| iterator TPI = find(AbsTy); |
| |
| // If there are any values in the symbol table of this type, then the type |
| // plan is a use of the abstract type which must be dropped. |
| if (TPI != end()) |
| AbsTy->removeAbstractTypeUser(this); |
| |
| TPI = find(Type::TypeTy); |
| if (TPI != end()) { |
| // Loop over all of the types in the symbol table, dropping any abstract |
| // type user entries for AbsTy which occur because there are names for the |
| // type. |
| // |
| VarMap &TyPlane = TPI->second; |
| for (VarMap::iterator I = TyPlane.begin(), E = TyPlane.end(); I != E; ++I) |
| if (I->second == (Value*)AbsTy) // FIXME when Types aren't const. |
| AbsTy->removeAbstractTypeUser(this); |
| } |
| } |
| |
| static void DumpVal(const std::pair<const std::string, Value *> &V) { |
| std::cout << " '" << V.first << "' = "; |
| V.second->dump(); |
| std::cout << "\n"; |
| } |
| |
| static void DumpPlane(const std::pair<const Type *, |
| std::map<const std::string, Value *> >&P){ |
| std::cout << " Plane: "; |
| P.first->dump(); |
| std::cout << "\n"; |
| for_each(P.second.begin(), P.second.end(), DumpVal); |
| } |
| |
| void SymbolTable::dump() const { |
| std::cout << "Symbol table dump:\n"; |
| for_each(begin(), end(), DumpPlane); |
| } |