#include "llvm/DerivedTypes.h"
#include "llvm/Pass.h"
#include "llvm/iOther.h"
-#include "llvm/Constant.h"
-#include "Support/StatisticReporter.h"
+#include "llvm/Constants.h"
+#include "llvm/Assembly/Writer.h" // FIXME: remove when varargs implemented
+#include "Support/Statistic.h"
#include <algorithm>
-using std::vector;
-using std::string;
-using std::cerr;
-
namespace {
- Statistic<>NumResolved("funcresolve\t- Number of varargs functions resolved");
+ Statistic<>NumResolved("funcresolve", "Number of varargs functions resolved");
+ Statistic<> NumGlobals("funcresolve", "Number of global variables resolved");
struct FunctionResolvingPass : public Pass {
bool run(Module &M);
// Keep an iterator to where we want to insert cast instructions if the
// argument types don't agree.
//
- BasicBlock::iterator BBI = CI;
- assert(CI->getNumOperands()-1 == ParamTys.size() &&
- "Function calls resolved funny somehow, incompatible number of args");
+ unsigned NumArgsToCopy = CI->getNumOperands()-1;
+ if (NumArgsToCopy != ParamTys.size() &&
+ !(NumArgsToCopy > ParamTys.size() &&
+ Dest->getFunctionType()->isVarArg())) {
+ std::cerr << "WARNING: Call arguments do not match expected number of"
+ << " parameters.\n";
+ std::cerr << "WARNING: In function '"
+ << CI->getParent()->getParent()->getName() << "': call: " << *CI;
+ std::cerr << "Function resolved to: ";
+ WriteAsOperand(std::cerr, Dest);
+ std::cerr << "\n";
+ if (NumArgsToCopy > ParamTys.size())
+ NumArgsToCopy = ParamTys.size();
+ }
- vector<Value*> Params;
+ std::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) {
+ for (unsigned i = 1; i <= NumArgsToCopy; ++i) {
Value *V = CI->getOperand(i);
- if (V->getType() != ParamTys[i-1]) // Must insert a cast...
- V = new CastInst(V, ParamTys[i-1], "argcast", BBI);
+ if (i-1 < ParamTys.size() && V->getType() != ParamTys[i-1]) {
+ // Must insert a cast...
+ V = new CastInst(V, ParamTys[i-1], "argcast", CI);
+ }
Params.push_back(V);
}
// Replace the old call instruction with a new call instruction that calls
// the real function.
//
- Instruction *NewCall = new CallInst(Dest, Params, "", BBI);
-
- // Remove the old call instruction from the program...
- BB->getInstList().remove(BBI);
+ Instruction *NewCall = new CallInst(Dest, Params, "", CI);
+ std::string Name = CI->getName(); CI->setName("");
// Transfer the name over...
if (NewCall->getType() != Type::VoidTy)
- NewCall->setName(CI->getName());
+ NewCall->setName(Name);
// Replace uses of the old instruction with the appropriate values...
//
if (NewCall->getType() == CI->getType()) {
CI->replaceAllUsesWith(NewCall);
- NewCall->setName(CI->getName());
+ NewCall->setName(Name);
} else if (NewCall->getType() == Type::VoidTy) {
// Resolved function does not return a value but the prototype does. This
//
if (!CI->use_empty()) {
// Insert the new cast instruction...
- CastInst *NewCast = new CastInst(NewCall, CI->getType(),
- NewCall->getName(), BBI);
+ CastInst *NewCast = new CastInst(NewCall, CI->getType(), Name, CI);
CI->replaceAllUsesWith(NewCast);
}
}
// The old instruction is no longer needed, destroy it!
- delete CI;
+ BB->getInstList().erase(CI);
}
+static bool ResolveFunctions(Module &M, std::vector<GlobalValue*> &Globals,
+ Function *Concrete) {
+ bool Changed = false;
+ for (unsigned i = 0; i != Globals.size(); ++i)
+ if (Globals[i] != Concrete) {
+ Function *Old = cast<Function>(Globals[i]);
+ const FunctionType *OldMT = Old->getFunctionType();
+ const FunctionType *ConcreteMT = Concrete->getFunctionType();
+
+ if (OldMT->getParamTypes().size() > ConcreteMT->getParamTypes().size() &&
+ !ConcreteMT->isVarArg())
+ if (!Old->use_empty()) {
+ std::cerr << "WARNING: Linking function '" << Old->getName()
+ << "' is causing arguments to be dropped.\n";
+ std::cerr << "WARNING: Prototype: ";
+ WriteAsOperand(std::cerr, Old);
+ std::cerr << " resolved to ";
+ WriteAsOperand(std::cerr, Concrete);
+ std::cerr << "\n";
+ }
+
+ // Check to make sure that if there are specified types, that they
+ // match...
+ //
+ unsigned NumArguments = std::min(OldMT->getParamTypes().size(),
+ ConcreteMT->getParamTypes().size());
+
+ if (!Old->use_empty() && !Concrete->use_empty())
+ for (unsigned i = 0; i < NumArguments; ++i)
+ if (OldMT->getParamTypes()[i] != ConcreteMT->getParamTypes()[i]) {
+ std::cerr << "WARNING: Function [" << Old->getName()
+ << "]: Parameter types conflict for: '" << OldMT
+ << "' and '" << ConcreteMT << "'\n";
+ return Changed;
+ }
+
+ // 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;
+ ++NumResolved;
+ } 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;
+ ++NumResolved;
+ } else {
+ std::cerr << "Couldn't cleanup this function call, must be an"
+ << " argument or something!" << CI;
+ ++i;
+ }
+ } else if (ConstantPointerRef *CPR = dyn_cast<ConstantPointerRef>(U)) {
+ if (CPR->use_size() == 1 && isa<ConstantExpr>(CPR->use_back()) &&
+ cast<ConstantExpr>(CPR->use_back())->getOpcode() ==
+ Instruction::Cast) {
+ ConstantExpr *CE = cast<ConstantExpr>(CPR->use_back());
+ Constant *NewCPR = ConstantPointerRef::get(Concrete);
+ CE->replaceAllUsesWith(ConstantExpr::getCast(NewCPR,CE->getType()));
+ CPR->destroyConstant();
+ } else {
+ std::cerr << "Cannot convert use of function: " << CPR << "\n";
+ ++i;
+ }
+ } else {
+ std::cerr << "Cannot convert use of function: " << U << "\n";
+ ++i;
+ }
+ }
+ }
+ return Changed;
+}
+
+
+static bool ResolveGlobalVariables(Module &M,
+ std::vector<GlobalValue*> &Globals,
+ GlobalVariable *Concrete) {
+ bool Changed = false;
+ assert(isa<ArrayType>(Concrete->getType()->getElementType()) &&
+ "Concrete version should be an array type!");
+
+ // Get the type of the things that may be resolved to us...
+ const ArrayType *CATy =cast<ArrayType>(Concrete->getType()->getElementType());
+ const Type *AETy = CATy->getElementType();
+
+ Constant *CCPR = ConstantPointerRef::get(Concrete);
+
+ for (unsigned i = 0; i != Globals.size(); ++i)
+ if (Globals[i] != Concrete) {
+ GlobalVariable *Old = cast<GlobalVariable>(Globals[i]);
+ const ArrayType *OATy = cast<ArrayType>(Old->getType()->getElementType());
+ if (OATy->getElementType() != AETy || OATy->getNumElements() != 0) {
+ std::cerr << "WARNING: Two global variables exist with the same name "
+ << "that cannot be resolved!\n";
+ return false;
+ }
+
+ Old->replaceAllUsesWith(ConstantExpr::getCast(CCPR, Old->getType()));
+
+ // Since there are no uses of Old anymore, remove it from the module.
+ M.getGlobalList().erase(Old);
+
+ ++NumGlobals;
+ Changed = true;
+ }
+ return Changed;
+}
+
+static bool ProcessGlobalsWithSameName(Module &M,
+ std::vector<GlobalValue*> &Globals) {
+ assert(!Globals.empty() && "Globals list shouldn't be empty here!");
+
+ bool isFunction = isa<Function>(Globals[0]); // Is this group all functions?
+ GlobalValue *Concrete = 0; // The most concrete implementation to resolve to
+
+ assert((isFunction ^ isa<GlobalVariable>(Globals[0])) &&
+ "Should either be function or gvar!");
+
+ for (unsigned i = 0; i != Globals.size(); ) {
+ if (isa<Function>(Globals[i]) != isFunction) {
+ std::cerr << "WARNING: Found function and global variable with the "
+ << "same name: '" << Globals[i]->getName() << "'.\n";
+ return false; // Don't know how to handle this, bail out!
+ }
+
+ if (isFunction) {
+ // For functions, we look to merge functions definitions of "int (...)"
+ // to 'int (int)' or 'int ()' or whatever else is not completely generic.
+ //
+ Function *F = cast<Function>(Globals[i]);
+ if (!F->isExternal()) {
+ if (Concrete && !Concrete->isExternal())
+ return false; // Found two different functions types. Can't choose!
+
+ Concrete = Globals[i];
+ } else if (Concrete) {
+ if (Concrete->isExternal()) // If we have multiple external symbols...x
+ if (F->getFunctionType()->getNumParams() >
+ cast<Function>(Concrete)->getFunctionType()->getNumParams())
+ Concrete = F; // We are more concrete than "Concrete"!
+
+ } else {
+ Concrete = F;
+ }
+ } else {
+ // For global variables, we have to merge C definitions int A[][4] with
+ // int[6][4]. A[][4] is represented as A[0][4] by the CFE.
+ GlobalVariable *GV = cast<GlobalVariable>(Globals[i]);
+ if (!isa<ArrayType>(GV->getType()->getElementType())) {
+ Concrete = 0;
+ break; // Non array's cannot be compatible with other types.
+ } else if (Concrete == 0) {
+ Concrete = GV;
+ } else {
+ // Must have different types... allow merging A[0][4] w/ A[6][4] if
+ // A[0][4] is external.
+ const ArrayType *NAT = cast<ArrayType>(GV->getType()->getElementType());
+ const ArrayType *CAT =
+ cast<ArrayType>(Concrete->getType()->getElementType());
+
+ if (NAT->getElementType() != CAT->getElementType()) {
+ Concrete = 0; // Non-compatible types
+ break;
+ } else if (NAT->getNumElements() == 0 && GV->isExternal()) {
+ // Concrete remains the same
+ } else if (CAT->getNumElements() == 0 && Concrete->isExternal()) {
+ Concrete = GV; // Concrete becomes GV
+ } else {
+ Concrete = 0; // Cannot merge these types...
+ break;
+ }
+ }
+ }
+ ++i;
+ }
+
+ if (Globals.size() > 1) { // Found a multiply defined global...
+ // We should find exactly one concrete function definition, which is
+ // probably the implementation. Change all of the function definitions and
+ // uses to use it instead.
+ //
+ if (!Concrete) {
+ std::cerr << "WARNING: Found global types that are not compatible:\n";
+ for (unsigned i = 0; i < Globals.size(); ++i) {
+ std::cerr << "\t" << Globals[i]->getType()->getDescription() << " %"
+ << Globals[i]->getName() << "\n";
+ }
+ std::cerr << " No linkage of globals named '" << Globals[0]->getName()
+ << "' performed!\n";
+ return false;
+ }
+
+ if (isFunction)
+ return ResolveFunctions(M, Globals, cast<Function>(Concrete));
+ else
+ return ResolveGlobalVariables(M, Globals,
+ cast<GlobalVariable>(Concrete));
+ }
+ return false;
+}
+
bool FunctionResolvingPass::run(Module &M) {
- SymbolTable *ST = M.getSymbolTable();
- if (!ST) return false;
+ SymbolTable &ST = M.getSymbolTable();
- std::map<string, vector<Function*> > Functions;
+ std::map<std::string, std::vector<GlobalValue*> > Globals;
// 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) {
- Function *F = cast<Function>(PI->second);
- assert(PI->first == F->getName() &&
- "Function name and symbol table do not agree!");
- if (F->hasExternalLinkage()) // Only resolve decls to external fns
- Functions[PI->first].push_back(F);
- }
+ for (SymbolTable::iterator I = ST.begin(), E = ST.end(); I != E; ++I)
+ if (const PointerType *PT = dyn_cast<PointerType>(I->first)) {
+ SymbolTable::VarMap &Plane = I->second;
+ for (SymbolTable::type_iterator PI = Plane.begin(), PE = Plane.end();
+ PI != PE; ++PI) {
+ GlobalValue *GV = cast<GlobalValue>(PI->second);
+ assert(PI->first == GV->getName() &&
+ "Global name and symbol table do not agree!");
+ if (!GV->hasInternalLinkage()) // Only resolve decls to external fns
+ Globals[PI->first].push_back(GV);
}
+ }
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
- if (Implementation != 0)
- 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_empty()) {
- M.getFunctionList().erase(Functions[i]);
- Functions.erase(Functions.begin()+i);
- Changed = true;
- ++NumResolved;
- 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;
+ for (std::map<std::string, std::vector<GlobalValue*> >::iterator
+ I = Globals.begin(), E = Globals.end(); I != E; ++I)
+ Changed |= ProcessGlobalsWithSameName(M, I->second);
+
+ // Now loop over all of the globals, checking to see if any are trivially
+ // dead. If so, remove them now.
+
+ for (Module::iterator I = M.begin(), E = M.end(); I != E; )
+ if (I->isExternal() && I->use_empty()) {
+ Function *F = I;
+ ++I;
+ M.getFunctionList().erase(F);
+ ++NumResolved;
+ Changed = true;
+ } else {
+ ++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(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;
- ++NumResolved;
- } 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;
- ++NumResolved;
- } 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;
- }
- }
- }
- }
+ for (Module::giterator I = M.gbegin(), E = M.gend(); I != E; )
+ if (I->isExternal() && I->use_empty()) {
+ GlobalVariable *GV = I;
+ ++I;
+ M.getGlobalList().erase(GV);
+ ++NumGlobals;
+ Changed = true;
+ } else {
+ ++I;
}
- }
return Changed;
}