- return Changed;
-}
-
-
-//===----------------------------------------------------------------------===//
-//
-// FunctionResolvingPass - Go over the functions that are in the module and
-// look for functions that have the same name. More often than not, there will
-// be things like:
-// void "foo"(...)
-// void "foo"(int, int)
-// because of the way things are declared in C. If this is the case, patch
-// things up.
-//
-//===----------------------------------------------------------------------===//
-
-namespace {
- struct FunctionResolvingPass : public Pass {
- bool run(Module *M);
- };
-}
-
-// ConvertCallTo - Convert a call to a varargs function with no arg types
-// specified to a concrete nonvarargs function.
-//
-static void ConvertCallTo(CallInst *CI, Function *Dest) {
- const FunctionType::ParamTypes &ParamTys =
- Dest->getFunctionType()->getParamTypes();
- BasicBlock *BB = CI->getParent();
-
- // Get an iterator to where we want to insert cast instructions if the
- // argument types don't agree.
- //
- BasicBlock::iterator BBI = find(BB->begin(), BB->end(), CI);
- assert(BBI != BB->end() && "CallInst not in parent block?");
-
- assert(CI->getNumOperands()-1 == ParamTys.size()&&
- "Function calls resolved funny somehow, incompatible number of args");
-
- vector<Value*> Params;
-
- // Convert all of the call arguments over... inserting cast instructions if
- // the types are not compatible.
- for (unsigned i = 1; i < CI->getNumOperands(); ++i) {
- Value *V = CI->getOperand(i);
-
- if (V->getType() != ParamTys[i-1]) { // Must insert a cast...
- Instruction *Cast = new CastInst(V, ParamTys[i-1]);
- BBI = BB->getInstList().insert(BBI, Cast)+1;
- V = Cast;
- }
-
- Params.push_back(V);
- }
-
- // Replace the old call instruction with a new call instruction that calls
- // the real function.
- //
- ReplaceInstWithInst(BB->getInstList(), BBI, new CallInst(Dest, Params));
-}
-
-
-bool FunctionResolvingPass::run(Module *M) {
- SymbolTable *ST = M->getSymbolTable();
- if (!ST) return false;
-
- std::map<string, vector<Function*> > Functions;
-
- // Loop over the entries in the symbol table. If an entry is a func pointer,
- // then add it to the Functions map. We do a two pass algorithm here to avoid
- // problems with iterators getting invalidated if we did a one pass scheme.
- //
- for (SymbolTable::iterator I = ST->begin(), E = ST->end(); I != E; ++I)
- if (const PointerType *PT = dyn_cast<PointerType>(I->first))
- if (isa<FunctionType>(PT->getElementType())) {
- SymbolTable::VarMap &Plane = I->second;
- for (SymbolTable::type_iterator PI = Plane.begin(), PE = Plane.end();
- PI != PE; ++PI) {
- const string &Name = PI->first;
- Functions[Name].push_back(cast<Function>(PI->second));
- }
- }
-
- bool Changed = false;
-
- // Now we have a list of all functions with a particular name. If there is
- // more than one entry in a list, merge the functions together.
- //
- for (std::map<string, vector<Function*> >::iterator I = Functions.begin(),
- E = Functions.end(); I != E; ++I) {
- vector<Function*> &Functions = I->second;
- Function *Implementation = 0; // Find the implementation
- Function *Concrete = 0;
- for (unsigned i = 0; i < Functions.size(); ) {
- if (!Functions[i]->isExternal()) { // Found an implementation
- assert(Implementation == 0 && "Multiple definitions of the same"
- " function. Case not handled yet!");
- Implementation = Functions[i];
- } else {
- // Ignore functions that are never used so they don't cause spurious
- // warnings... here we will actually DCE the function so that it isn't
- // used later.
- //
- if (Functions[i]->use_size() == 0) {
- M->getFunctionList().remove(Functions[i]);
- delete Functions[i];
- Functions.erase(Functions.begin()+i);
- Changed = true;
- continue;
- }
- }
-
- if (Functions[i] && (!Functions[i]->getFunctionType()->isVarArg())) {
- if (Concrete) { // Found two different functions types. Can't choose
- Concrete = 0;
- break;
- }
- Concrete = Functions[i];
- }
- ++i;
- }
-
- if (Functions.size() > 1) { // Found a multiply defined function...
- // We should find exactly one non-vararg function definition, which is
- // probably the implementation. Change all of the function definitions
- // and uses to use it instead.
- //
- if (!Concrete) {
- cerr << "Warning: Found functions types that are not compatible:\n";
- for (unsigned i = 0; i < Functions.size(); ++i) {
- cerr << "\t" << Functions[i]->getType()->getDescription() << " %"
- << Functions[i]->getName() << "\n";
- }
- cerr << " No linkage of functions named '" << Functions[0]->getName()
- << "' performed!\n";
- } else {
- for (unsigned i = 0; i < Functions.size(); ++i)
- if (Functions[i] != Concrete) {
- Function *Old = Functions[i];
- const FunctionType *OldMT = Old->getFunctionType();
- const FunctionType *ConcreteMT = Concrete->getFunctionType();
- bool Broken = false;
-
- assert(Old->getReturnType() == Concrete->getReturnType() &&
- "Differing return types not handled yet!");
- assert(OldMT->getParamTypes().size() <=
- ConcreteMT->getParamTypes().size() &&
- "Concrete type must have more specified parameters!");
-
- // Check to make sure that if there are specified types, that they
- // match...
- //
- for (unsigned i = 0; i < OldMT->getParamTypes().size(); ++i)
- if (OldMT->getParamTypes()[i] != ConcreteMT->getParamTypes()[i]) {
- cerr << "Parameter types conflict for" << OldMT
- << " and " << ConcreteMT;
- Broken = true;
- }
- if (Broken) break; // Can't process this one!
-
-
- // Attempt to convert all of the uses of the old function to the
- // concrete form of the function. If there is a use of the fn
- // that we don't understand here we punt to avoid making a bad
- // transformation.
- //
- // At this point, we know that the return values are the same for
- // our two functions and that the Old function has no varargs fns
- // specified. In otherwords it's just <retty> (...)
- //
- for (unsigned i = 0; i < Old->use_size(); ) {
- User *U = *(Old->use_begin()+i);
- if (CastInst *CI = dyn_cast<CastInst>(U)) {
- // Convert casts directly
- assert(CI->getOperand(0) == Old);
- CI->setOperand(0, Concrete);
- Changed = true;
- } else if (CallInst *CI = dyn_cast<CallInst>(U)) {
- // Can only fix up calls TO the argument, not args passed in.
- if (CI->getCalledValue() == Old) {
- ConvertCallTo(CI, Concrete);
- Changed = true;
- } else {
- cerr << "Couldn't cleanup this function call, must be an"
- << " argument or something!" << CI;
- ++i;
- }
- } else {
- cerr << "Cannot convert use of function: " << U << "\n";
- ++i;
- }
- }
- }
- }
- }
- }