| //===-- SymbolTable.cpp - Implement the SymbolTable class -----------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file was developed by the LLVM research group and revised by Reid |
| // Spencer. It is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements the SymbolTable class for the VMCore library. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "llvm/SymbolTable.h" |
| #include "llvm/DerivedTypes.h" |
| #include "llvm/Module.h" |
| #include "llvm/ADT/StringExtras.h" |
| #include <algorithm> |
| #include <iostream> |
| |
| using namespace llvm; |
| |
| #define DEBUG_SYMBOL_TABLE 0 |
| #define DEBUG_ABSTYPE 0 |
| |
| SymbolTable::~SymbolTable() { |
| // Drop all abstract type references in the type plane... |
| for (type_iterator TI = tmap.begin(), TE = tmap.end(); TI != TE; ++TI) { |
| if (TI->second->isAbstract()) // If abstract, drop the reference... |
| cast<DerivedType>(TI->second)->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 (plane_iterator PI = pmap.begin(); PI != pmap.end(); ++PI) { |
| for (value_iterator VI = PI->second.begin(); VI != PI->second.end(); ++VI) |
| if (!isa<Constant>(VI->second) ) { |
| std::cerr << "Value still in symbol table! Type = '" |
| << PI->first->getDescription() << "' Name = '" |
| << VI->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) const { |
| // Find the plane |
| plane_const_iterator PI = pmap.find(Ty); |
| if (PI == pmap.end()) return BaseName; |
| |
| std::string TryName = BaseName; |
| const ValueMap& vmap = PI->second; |
| value_const_iterator End = vmap.end(); |
| |
| // See if the name exists |
| while (vmap.find(TryName) != End) // Loop until we find a free |
| TryName = BaseName + utostr(++LastUnique); // name in the symbol table |
| return TryName; |
| } |
| |
| |
| // lookup a value - Returns null on failure... |
| Value *SymbolTable::lookup(const Type *Ty, const std::string &Name) const { |
| plane_const_iterator PI = pmap.find(Ty); |
| if (PI != pmap.end()) { // We have symbols in that plane. |
| value_const_iterator VI = PI->second.find(Name); |
| if (VI != PI->second.end()) // and the name is in our hash table. |
| return VI->second; |
| } |
| return 0; |
| } |
| |
| |
| // lookup a type by name - returns null on failure |
| Type* SymbolTable::lookupType(const std::string& Name) const { |
| type_const_iterator TI = tmap.find(Name); |
| if (TI != tmap.end()) |
| return const_cast<Type*>(TI->second); |
| return 0; |
| } |
| |
| /// changeName - Given a value with a non-empty name, remove its existing entry |
| /// from the symbol table and insert a new one for Name. This is equivalent to |
| /// doing "remove(V), V->Name = Name, insert(V)", but is faster, and will not |
| /// temporarily remove the symbol table plane if V is the last value in the |
| /// symtab with that name (which could invalidate iterators to that plane). |
| void SymbolTable::changeName(Value *V, const std::string &name) { |
| assert(!V->getName().empty() && !name.empty() && V->getName() != name && |
| "Illegal use of this method!"); |
| |
| plane_iterator PI = pmap.find(V->getType()); |
| assert(PI != pmap.end() && "Value doesn't have an entry in this table?"); |
| ValueMap &VM = PI->second; |
| |
| value_iterator VI = VM.find(V->getName()); |
| assert(VI != VM.end() && "Value does have an entry in this table?"); |
| |
| // Remove the old entry. |
| VM.erase(VI); |
| |
| // See if we can insert the new name. |
| VI = VM.lower_bound(name); |
| |
| // Is there a naming conflict? |
| if (VI != VM.end() && VI->first == name) { |
| V->Name = getUniqueName(V->getType(), name); |
| VM.insert(make_pair(V->Name, V)); |
| } else { |
| V->Name = name; |
| VM.insert(VI, make_pair(name, V)); |
| } |
| } |
| |
| // Remove a value |
| void SymbolTable::remove(Value *N) { |
| assert(N->hasName() && "Value doesn't have name!"); |
| |
| plane_iterator PI = pmap.find(N->getType()); |
| assert(PI != pmap.end() && |
| "Trying to remove a value that doesn't have a type plane yet!"); |
| ValueMap &VM = PI->second; |
| value_iterator Entry = VM.find(N->getName()); |
| assert(Entry != VM.end() && "Invalid entry to remove!"); |
| |
| #if DEBUG_SYMBOL_TABLE |
| dump(); |
| std::cerr << " Removing Value: " << Entry->second->getName() << "\n"; |
| #endif |
| |
| // Remove the value from the plane... |
| VM.erase(Entry); |
| |
| // If the plane is empty, remove it now! |
| if (VM.empty()) { |
| // If the plane represented an abstract type that we were interested in, |
| // unlink ourselves from this plane. |
| // |
| if (N->getType()->isAbstract()) { |
| #if DEBUG_ABSTYPE |
| std::cerr << "Plane Empty: Removing type: " |
| << N->getType()->getDescription() << "\n"; |
| #endif |
| cast<DerivedType>(N->getType())->removeAbstractTypeUser(this); |
| } |
| |
| pmap.erase(PI); |
| } |
| } |
| |
| // remove - Remove a type from the symbol table... |
| Type* SymbolTable::remove(type_iterator Entry) { |
| assert(Entry != tmap.end() && "Invalid entry to remove!"); |
| |
| const Type* Result = Entry->second; |
| |
| #if DEBUG_SYMBOL_TABLE |
| dump(); |
| std::cerr << " Removing Value: " << Result->getName() << "\n"; |
| #endif |
| |
| tmap.erase(Entry); |
| |
| // If we are removing an abstract type, remove the symbol table from it's use |
| // list... |
| if (Result->isAbstract()) { |
| #if DEBUG_ABSTYPE |
| std::cerr << "Removing abstract type from symtab" << Result->getDescription()<<"\n"; |
| #endif |
| cast<DerivedType>(Result)->removeAbstractTypeUser(this); |
| } |
| |
| return const_cast<Type*>(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) { |
| plane_iterator PI = pmap.find(VTy); // Plane iterator |
| value_iterator VI; // Actual value iterator |
| ValueMap *VM; // The plane we care about. |
| |
| #if DEBUG_SYMBOL_TABLE |
| dump(); |
| std::cerr << " Inserting definition: " << Name << ": " |
| << VTy->getDescription() << "\n"; |
| #endif |
| |
| if (PI == pmap.end()) { // Not in collection yet... insert dummy entry |
| // Insert a new empty element. I points to the new elements. |
| VM = &pmap.insert(make_pair(VTy, ValueMap())).first->second; |
| VI = VM->end(); |
| |
| // 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 |
| } |
| |
| } else { |
| // Check to see if there is a naming conflict. If so, rename this value! |
| VM = &PI->second; |
| VI = VM->lower_bound(Name); |
| if (VI != VM->end() && VI->first == Name) { |
| V->Name = getUniqueName(VTy, Name); |
| VM->insert(make_pair(V->Name, V)); |
| return; |
| } |
| } |
| |
| VM->insert(VI, make_pair(Name, V)); |
| } |
| |
| |
| // insertEntry - Insert a value into the symbol table with the specified |
| // name... |
| // |
| void SymbolTable::insert(const std::string& Name, const Type* T) { |
| assert(T && "Can't insert null type into symbol table!"); |
| |
| // Check to see if there is a naming conflict. If so, rename this type! |
| std::string UniqueName = Name; |
| if (lookupType(Name)) |
| UniqueName = getUniqueName(T, Name); |
| |
| #if DEBUG_SYMBOL_TABLE |
| dump(); |
| std::cerr << " Inserting type: " << UniqueName << ": " |
| << T->getDescription() << "\n"; |
| #endif |
| |
| // Insert the tmap entry |
| tmap.insert(make_pair(UniqueName, T)); |
| |
| // If we are adding an abstract type, add the symbol table to it's use list. |
| if (T->isAbstract()) { |
| cast<DerivedType>(T)->addAbstractTypeUser(this); |
| #if DEBUG_ABSTYPE |
| std::cerr << "Added abstract type to ST: " << T->getDescription() << "\n"; |
| #endif |
| } |
| } |
| |
| // Strip the symbol table of its names. |
| bool SymbolTable::strip() { |
| bool RemovedSymbol = false; |
| for (plane_iterator I = pmap.begin(); I != pmap.end();) { |
| // Removing items from the plane can cause the plane itself to get deleted. |
| // If this happens, make sure we incremented our plane iterator already! |
| ValueMap &Plane = (I++)->second; |
| value_iterator B = Plane.begin(), Bend = Plane.end(); |
| while (B != Bend) { // Found nonempty type plane! |
| Value *V = B->second; |
| if (!isa<GlobalValue>(V) || cast<GlobalValue>(V)->hasInternalLinkage()) { |
| // Set name to "", removing from symbol table! |
| V->setName(""); |
| RemovedSymbol = true; |
| } |
| ++B; |
| } |
| } |
| |
| for (type_iterator TI = tmap.begin(); TI != tmap.end(); ) { |
| remove(TI++); |
| RemovedSymbol = true; |
| } |
| |
| return RemovedSymbol; |
| } |
| |
| |
| // 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... |
| plane_iterator PI = pmap.find(OldType); |
| if (PI != pmap.end()) { |
| // Get a handle to the new type plane... |
| plane_iterator NewTypeIt = pmap.find(NewType); |
| if (NewTypeIt == pmap.end()) { // If no plane exists, add one |
| NewTypeIt = pmap.insert(make_pair(NewType, ValueMap())).first; |
| |
| if (NewType->isAbstract()) { |
| cast<DerivedType>(NewType)->addAbstractTypeUser(this); |
| #if DEBUG_ABSTYPE |
| std::cerr << "[Added] refined to abstype: " << NewType->getDescription() |
| << "\n"; |
| #endif |
| } |
| } |
| |
| ValueMap &NewPlane = NewTypeIt->second; |
| ValueMap &OldPlane = PI->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. |
| value_iterator VI = NewPlane.find(V.first); |
| if (VI != NewPlane.end() && VI->second == V.second) { |
| // No action |
| |
| } else if (VI != NewPlane.end()) { |
| // The only thing we are allowing for now is two external global values |
| // folded into one. |
| // |
| GlobalValue *ExistGV = dyn_cast<GlobalValue>(VI->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); |
| |
| // Update NewGV's name, we're about the remove it from the symbol |
| // table. |
| NewGV->Name = ""; |
| |
| // 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 { |
| // If they are not global values, they must be just random values who |
| // happen to conflict now that types have been resolved. If this is |
| // the case, reinsert the value into the new plane, allowing it to get |
| // renamed. |
| assert(V.second->getType() == NewType &&"Type resolution is broken!"); |
| insert(V.second); |
| } |
| } 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 |
| pmap.erase(PI); |
| } |
| |
| // 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. |
| // |
| for (type_iterator I = type_begin(), E = type_end(); I != E; ++I) { |
| if (I->second == (Type*)OldType) { // FIXME when Types aren't const. |
| #if DEBUG_ABSTYPE |
| std::cerr << "Removing type " << OldType->getDescription() << "\n"; |
| #endif |
| OldType->removeAbstractTypeUser(this); |
| |
| I->second = (Type*)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); |
| } |
| } |
| } |
| } |
| |
| |
| // Handle situation where type becomes Concreate from Abstract |
| void SymbolTable::typeBecameConcrete(const DerivedType *AbsTy) { |
| plane_iterator PI = pmap.find(AbsTy); |
| |
| // If there are any values in the symbol table of this type, then the type |
| // plane is a use of the abstract type which must be dropped. |
| if (PI != pmap.end()) |
| AbsTy->removeAbstractTypeUser(this); |
| |
| // 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. |
| for (type_iterator TI = type_begin(), TE = type_end(); TI != TE; ++TI) |
| if (TI->second == (Type*)AbsTy) // FIXME when Types aren't const. |
| AbsTy->removeAbstractTypeUser(this); |
| } |
| |
| static void DumpVal(const std::pair<const std::string, Value *> &V) { |
| std::cerr << " '" << V.first << "' = "; |
| V.second->dump(); |
| std::cerr << "\n"; |
| } |
| |
| static void DumpPlane(const std::pair<const Type *, |
| std::map<const std::string, Value *> >&P){ |
| P.first->dump(); |
| std::cerr << "\n"; |
| for_each(P.second.begin(), P.second.end(), DumpVal); |
| } |
| |
| static void DumpTypes(const std::pair<const std::string, const Type*>& T ) { |
| std::cerr << " '" << T.first << "' = "; |
| T.second->dump(); |
| std::cerr << "\n"; |
| } |
| |
| void SymbolTable::dump() const { |
| std::cerr << "Symbol table dump:\n Plane:"; |
| for_each(pmap.begin(), pmap.end(), DumpPlane); |
| std::cerr << " Types: "; |
| for_each(tmap.begin(), tmap.end(), DumpTypes); |
| } |
| |
| // vim: sw=2 ai |