-//===-- SymbolTable.cpp - Implement the SymbolTable class -------------------=//
+//===-- 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/InstrTypes.h"
-#include "llvm/Support/StringExtras.h"
-#ifndef NDEBUG
-#include "llvm/BasicBlock.h" // Required for assertions to work.
-#include "llvm/Type.h"
-#endif
+#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() {
-#ifndef NDEBUG // Only do this in -g mode...
- bool Good = true;
- for (iterator i = begin(); i != end(); ++i) {
- if (i->second.begin() != i->second.end()) {
- for (type_iterator I = i->second.begin(); I != i->second.end(); ++I)
- cerr << "Value still in symbol table! Type = " << i->first->getName()
- << " Name = " << I->first << endl;
- Good = false;
- }
+ // 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);
}
- assert(Good && "Values remain in symbol table!");
-#endif
-}
-
-SymbolTable::type_iterator SymbolTable::type_find(const Value *D) {
- assert(D->hasName() && "type_find(Value*) only works on named nodes!");
- return type_find(D->getType(), D->getName());
-}
+ // TODO: FIXME: BIG ONE: This doesn't unreference abstract types for the
+ // planes that could still have entries!
-// find - returns end(Ty->getIDNumber()) on failure...
-SymbolTable::type_iterator SymbolTable::type_find(const Type *Ty,
- const string &Name) {
- iterator I = find(Ty);
- if (I == end()) { // Not in collection yet... insert dummy entry
- (*this)[Ty] = VarMap();
- I = find(Ty);
- assert(I != end() && "How did insert fail?");
+#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;
+ }
}
- return I->second.find(Name);
+ 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.
//
-string SymbolTable::getUniqueName(const Type *Ty, const string &BaseName) {
- iterator I = find(Ty);
- if (I == end()) return BaseName;
+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;
- string TryName = BaseName;
- unsigned Counter = 0;
- type_iterator End = I->second.end();
+ std::string TryName = BaseName;
+ const ValueMap& vmap = PI->second;
+ value_const_iterator End = vmap.end();
- while (I->second.find(TryName) != End) // Loop until we find unoccupied
- TryName = BaseName + utostr(++Counter); // Name in the symbol table
+ // 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 - Returns null on failure...
-Value *SymbolTable::lookup(const Type *Ty, const 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;
+// 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);
- return ParentSymTab ? ParentSymTab->lookup(Ty, Name) : 0;
+ // 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!");
- assert(type_find(N) != type_end(N->getType()) &&
- "Value not in symbol table!");
- type_remove(type_find(N));
+
+ 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!");
-#define DEBUG_SYMBOL_TABLE 0
+ const Type* Result = Entry->second;
-Value *SymbolTable::type_remove(const type_iterator &It) {
- Value *Result = It->second;
#if DEBUG_SYMBOL_TABLE
- cerr << this << " Removing Value: " << Result->getName() << endl;
+ dump();
+ std::cerr << " Removing Value: " << Result->getName() << "\n";
#endif
- find(Result->getType())->second.erase(It);
+ 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 Result;
+ return const_cast<Type*>(Result);
}
-void SymbolTable::insert(Value *N) {
- assert(N->hasName() && "Value must be named to go into symbol table!");
- // TODO: The typeverifier should catch this when its implemented
- if (lookup(N->getType(), N->getName())) {
- cerr << "SymbolTable WARNING: Name already in symbol table: '"
- << N->getName() << "'\n";
- abort(); // TODO: REMOVE THIS
+// 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
- cerr << this << " Inserting definition: " << N->getName() << ": "
- << N->getType()->getName() << endl;
+ dump();
+ std::cerr << " Inserting type: " << UniqueName << ": "
+ << T->getDescription() << "\n";
#endif
- iterator I = find(N->getType());
- if (I == end()) { // Not in collection yet... insert dummy entry
- (*this)[N->getType()] = VarMap();
- I = find(N->getType());
- assert(I != end() && "How did insert fail?");
+ // 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;
+ ++B;
+ if (!isa<GlobalValue>(V) || cast<GlobalValue>(V)->hasInternalLinkage()) {
+ // Set name to "", removing from symbol table!
+ V->setName("");
+ RemovedSymbol = true;
+ }
+ }
+ }
+
+ 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";
+}
- I->second.insert(make_pair(N->getName(), 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