//===- Linker.cpp - Module Linker Implementation --------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
//
// This file implements the LLVM module linker.
//
// Specifically, this:
// * Merges global variables between the two modules
// * Uninit + Uninit = Init, Init + Uninit = Init, Init + Init = Error if !=
-// * Merges methods between two modules
+// * Merges functions between two modules
//
//===----------------------------------------------------------------------===//
-#include "llvm/Transforms/Linker.h"
+#include "llvm/Transforms/Utils/Linker.h"
+#include "llvm/Constants.h"
+#include "llvm/DerivedTypes.h"
#include "llvm/Module.h"
-#include "llvm/Method.h"
-#include "llvm/GlobalVariable.h"
#include "llvm/SymbolTable.h"
-#include "llvm/DerivedTypes.h"
#include "llvm/iOther.h"
-#include "llvm/ConstPoolVals.h"
+#include "llvm/Assembly/Writer.h"
+
+namespace llvm {
// Error - Simple wrapper function to conditionally assign to E and return true.
// This just makes error return conditions a little bit simpler...
//
-static inline bool Error(string *E, string Message) {
+static inline bool Error(std::string *E, const std::string &Message) {
if (E) *E = Message;
return true;
}
-#include "llvm/Assembly/Writer.h" // TODO: REMOVE
+//
+// Function: ResolveTypes()
+//
+// Description:
+// Attempt to link the two specified types together.
+//
+// Inputs:
+// DestTy - The type to which we wish to resolve.
+// SrcTy - The original type which we want to resolve.
+// Name - The name of the type.
+//
+// Outputs:
+// DestST - The symbol table in which the new type should be placed.
+//
+// Return value:
+// true - There is an error and the types cannot yet be linked.
+// false - No errors.
+//
+static bool ResolveTypes(const Type *DestTy, const Type *SrcTy,
+ SymbolTable *DestST, const std::string &Name) {
+ if (DestTy == SrcTy) return false; // If already equal, noop
+
+ // Does the type already exist in the module?
+ if (DestTy && !isa<OpaqueType>(DestTy)) { // Yup, the type already exists...
+ if (const OpaqueType *OT = dyn_cast<OpaqueType>(SrcTy)) {
+ const_cast<OpaqueType*>(OT)->refineAbstractTypeTo(DestTy);
+ } else {
+ return true; // Cannot link types... neither is opaque and not-equal
+ }
+ } else { // Type not in dest module. Add it now.
+ if (DestTy) // Type _is_ in module, just opaque...
+ const_cast<OpaqueType*>(cast<OpaqueType>(DestTy))
+ ->refineAbstractTypeTo(SrcTy);
+ else if (!Name.empty())
+ DestST->insert(Name, const_cast<Type*>(SrcTy));
+ }
+ return false;
+}
+
+static const FunctionType *getFT(const PATypeHolder &TH) {
+ return cast<FunctionType>(TH.get());
+}
+static const StructType *getST(const PATypeHolder &TH) {
+ return cast<StructType>(TH.get());
+}
+
+// RecursiveResolveTypes - This is just like ResolveTypes, except that it
+// recurses down into derived types, merging the used types if the parent types
+// are compatible.
+//
+static bool RecursiveResolveTypesI(const PATypeHolder &DestTy,
+ const PATypeHolder &SrcTy,
+ SymbolTable *DestST, const std::string &Name,
+ std::vector<std::pair<PATypeHolder, PATypeHolder> > &Pointers) {
+ const Type *SrcTyT = SrcTy.get();
+ const Type *DestTyT = DestTy.get();
+ if (DestTyT == SrcTyT) return false; // If already equal, noop
+
+ // If we found our opaque type, resolve it now!
+ if (isa<OpaqueType>(DestTyT) || isa<OpaqueType>(SrcTyT))
+ return ResolveTypes(DestTyT, SrcTyT, DestST, Name);
+
+ // Two types cannot be resolved together if they are of different primitive
+ // type. For example, we cannot resolve an int to a float.
+ if (DestTyT->getPrimitiveID() != SrcTyT->getPrimitiveID()) return true;
+
+ // Otherwise, resolve the used type used by this derived type...
+ switch (DestTyT->getPrimitiveID()) {
+ case Type::FunctionTyID: {
+ if (cast<FunctionType>(DestTyT)->isVarArg() !=
+ cast<FunctionType>(SrcTyT)->isVarArg() ||
+ cast<FunctionType>(DestTyT)->getNumContainedTypes() !=
+ cast<FunctionType>(SrcTyT)->getNumContainedTypes())
+ return true;
+ for (unsigned i = 0, e = getFT(DestTy)->getNumContainedTypes(); i != e; ++i)
+ if (RecursiveResolveTypesI(getFT(DestTy)->getContainedType(i),
+ getFT(SrcTy)->getContainedType(i), DestST, "",
+ Pointers))
+ return true;
+ return false;
+ }
+ case Type::StructTyID: {
+ if (getST(DestTy)->getNumContainedTypes() !=
+ getST(SrcTy)->getNumContainedTypes()) return 1;
+ for (unsigned i = 0, e = getST(DestTy)->getNumContainedTypes(); i != e; ++i)
+ if (RecursiveResolveTypesI(getST(DestTy)->getContainedType(i),
+ getST(SrcTy)->getContainedType(i), DestST, "",
+ Pointers))
+ return true;
+ return false;
+ }
+ case Type::ArrayTyID: {
+ const ArrayType *DAT = cast<ArrayType>(DestTy.get());
+ const ArrayType *SAT = cast<ArrayType>(SrcTy.get());
+ if (DAT->getNumElements() != SAT->getNumElements()) return true;
+ return RecursiveResolveTypesI(DAT->getElementType(), SAT->getElementType(),
+ DestST, "", Pointers);
+ }
+ case Type::PointerTyID: {
+ // If this is a pointer type, check to see if we have already seen it. If
+ // so, we are in a recursive branch. Cut off the search now. We cannot use
+ // an associative container for this search, because the type pointers (keys
+ // in the container) change whenever types get resolved...
+ //
+ for (unsigned i = 0, e = Pointers.size(); i != e; ++i)
+ if (Pointers[i].first == DestTy)
+ return Pointers[i].second != SrcTy;
+
+ // Otherwise, add the current pointers to the vector to stop recursion on
+ // this pair.
+ Pointers.push_back(std::make_pair(DestTyT, SrcTyT));
+ bool Result =
+ RecursiveResolveTypesI(cast<PointerType>(DestTy.get())->getElementType(),
+ cast<PointerType>(SrcTy.get())->getElementType(),
+ DestST, "", Pointers);
+ Pointers.pop_back();
+ return Result;
+ }
+ default: assert(0 && "Unexpected type!"); return true;
+ }
+}
+
+static bool RecursiveResolveTypes(const PATypeHolder &DestTy,
+ const PATypeHolder &SrcTy,
+ SymbolTable *DestST, const std::string &Name){
+ std::vector<std::pair<PATypeHolder, PATypeHolder> > PointerTypes;
+ return RecursiveResolveTypesI(DestTy, SrcTy, DestST, Name, PointerTypes);
+}
// LinkTypes - Go through the symbol table of the Src module and see if any
// types are named in the src module that are not named in the Dst module.
// Make sure there are no type name conflicts.
//
-static bool LinkTypes(Module *Dest, const Module *Src, string *Err = 0) {
- // No symbol table? Can't have named types.
- if (!Src->hasSymbolTable()) return false;
-
- SymbolTable *DestST = Dest->getSymbolTableSure();
- const SymbolTable *SrcST = Src->getSymbolTable();
+static bool LinkTypes(Module *Dest, const Module *Src, std::string *Err) {
+ SymbolTable *DestST = &Dest->getSymbolTable();
+ const SymbolTable *SrcST = &Src->getSymbolTable();
// Look for a type plane for Type's...
SymbolTable::const_iterator PI = SrcST->find(Type::TypeTy);
if (PI == SrcST->end()) return false; // No named types, do nothing.
+ // Some types cannot be resolved immediately because they depend on other
+ // types being resolved to each other first. This contains a list of types we
+ // are waiting to recheck.
+ std::vector<std::string> DelayedTypesToResolve;
+
const SymbolTable::VarMap &VM = PI->second;
for (SymbolTable::type_const_iterator I = VM.begin(), E = VM.end();
I != E; ++I) {
- const string &Name = I->first;
- const Type *RHS = cast<Type>(I->second);
+ const std::string &Name = I->first;
+ Type *RHS = cast<Type>(I->second);
// Check to see if this type name is already in the dest module...
- const Type *Entry = cast_or_null<Type>(DestST->lookup(Type::TypeTy, Name));
- if (Entry) { // Yup, the value already exists...
- if (Entry != RHS) // If it's the same, noop. Otherwise, error.
- return Error(Err, "Type named '" + Name +
- "' of different shape in modules.\n Src='" +
- Entry->getDescription() + "'. Dest='" +
- RHS->getDescription() + "'");
- } else { // Type not in dest module. Add it now.
- // TODO: FIXME WHEN TYPES AREN'T CONST
- DestST->insert(Name, const_cast<Type*>(RHS));
+ Type *Entry = cast_or_null<Type>(DestST->lookup(Type::TypeTy, Name));
+
+ if (ResolveTypes(Entry, RHS, DestST, Name)) {
+ // They look different, save the types 'till later to resolve.
+ DelayedTypesToResolve.push_back(Name);
}
}
+
+ // Iteratively resolve types while we can...
+ while (!DelayedTypesToResolve.empty()) {
+ // Loop over all of the types, attempting to resolve them if possible...
+ unsigned OldSize = DelayedTypesToResolve.size();
+
+ // Try direct resolution by name...
+ for (unsigned i = 0; i != DelayedTypesToResolve.size(); ++i) {
+ const std::string &Name = DelayedTypesToResolve[i];
+ Type *T1 = cast<Type>(VM.find(Name)->second);
+ Type *T2 = cast<Type>(DestST->lookup(Type::TypeTy, Name));
+ if (!ResolveTypes(T2, T1, DestST, Name)) {
+ // We are making progress!
+ DelayedTypesToResolve.erase(DelayedTypesToResolve.begin()+i);
+ --i;
+ }
+ }
+
+ // Did we not eliminate any types?
+ if (DelayedTypesToResolve.size() == OldSize) {
+ // Attempt to resolve subelements of types. This allows us to merge these
+ // two types: { int* } and { opaque* }
+ for (unsigned i = 0, e = DelayedTypesToResolve.size(); i != e; ++i) {
+ const std::string &Name = DelayedTypesToResolve[i];
+ PATypeHolder T1(cast<Type>(VM.find(Name)->second));
+ PATypeHolder T2(cast<Type>(DestST->lookup(Type::TypeTy, Name)));
+
+ if (!RecursiveResolveTypes(T2, T1, DestST, Name)) {
+ // We are making progress!
+ DelayedTypesToResolve.erase(DelayedTypesToResolve.begin()+i);
+
+ // Go back to the main loop, perhaps we can resolve directly by name
+ // now...
+ break;
+ }
+ }
+
+ // If we STILL cannot resolve the types, then there is something wrong.
+ // Report the warning and delete one of the names.
+ if (DelayedTypesToResolve.size() == OldSize) {
+ const std::string &Name = DelayedTypesToResolve.back();
+
+ const Type *T1 = cast<Type>(VM.find(Name)->second);
+ const Type *T2 = cast<Type>(DestST->lookup(Type::TypeTy, Name));
+ std::cerr << "WARNING: Type conflict between types named '" << Name
+ << "'.\n Src='";
+ WriteTypeSymbolic(std::cerr, T1, Src);
+ std::cerr << "'.\n Dest='";
+ WriteTypeSymbolic(std::cerr, T2, Dest);
+ std::cerr << "'\n";
+
+ // Remove the symbol name from the destination.
+ DelayedTypesToResolve.pop_back();
+ }
+ }
+ }
+
+
return false;
}
-static void PrintMap(const map<const Value*, Value*> &M) {
- for (map<const Value*, Value*>::const_iterator I = M.begin(), E = M.end();
+static void PrintMap(const std::map<const Value*, Value*> &M) {
+ for (std::map<const Value*, Value*>::const_iterator I = M.begin(), E =M.end();
I != E; ++I) {
- cerr << " Fr: " << (void*)I->first << " " << I->first
- << " To: " << (void*)I->second << " " << I->second << endl;
+ std::cerr << " Fr: " << (void*)I->first << " ";
+ I->first->dump();
+ std::cerr << " To: " << (void*)I->second << " ";
+ I->second->dump();
+ std::cerr << "\n";
}
}
// module to another. This is somewhat sophisticated in that it can
// automatically handle constant references correctly as well...
//
-static Value *RemapOperand(const Value *In, map<const Value*, Value*> &LocalMap,
- const map<const Value*, Value*> *GlobalMap = 0) {
- map<const Value*,Value*>::const_iterator I = LocalMap.find(In);
+static Value *RemapOperand(const Value *In,
+ std::map<const Value*, Value*> &LocalMap,
+ std::map<const Value*, Value*> *GlobalMap) {
+ std::map<const Value*,Value*>::const_iterator I = LocalMap.find(In);
if (I != LocalMap.end()) return I->second;
if (GlobalMap) {
}
// Check to see if it's a constant that we are interesting in transforming...
- if (ConstPoolVal *CPV = dyn_cast<ConstPoolVal>(In)) {
- if (!isa<DerivedType>(CPV->getType()))
- return CPV; // Simple constants stay identical...
+ if (const Constant *CPV = dyn_cast<Constant>(In)) {
+ if (!isa<DerivedType>(CPV->getType()) && !isa<ConstantExpr>(CPV))
+ return const_cast<Constant*>(CPV); // Simple constants stay identical...
- ConstPoolVal *Result = 0;
+ Constant *Result = 0;
- if (ConstPoolArray *CPA = dyn_cast<ConstPoolArray>(CPV)) {
- const vector<Use> &Ops = CPA->getValues();
- vector<ConstPoolVal*> Operands(Ops.size());
- for (unsigned i = 0; i < Ops.size(); ++i)
+ if (const ConstantArray *CPA = dyn_cast<ConstantArray>(CPV)) {
+ const std::vector<Use> &Ops = CPA->getValues();
+ std::vector<Constant*> Operands(Ops.size());
+ for (unsigned i = 0, e = Ops.size(); i != e; ++i)
Operands[i] =
- cast<ConstPoolVal>(RemapOperand(Ops[i], LocalMap, GlobalMap));
- Result = ConstPoolArray::get(cast<ArrayType>(CPA->getType()), Operands);
- } else if (ConstPoolStruct *CPS = dyn_cast<ConstPoolStruct>(CPV)) {
- const vector<Use> &Ops = CPS->getValues();
- vector<ConstPoolVal*> Operands(Ops.size());
+ cast<Constant>(RemapOperand(Ops[i], LocalMap, GlobalMap));
+ Result = ConstantArray::get(cast<ArrayType>(CPA->getType()), Operands);
+ } else if (const ConstantStruct *CPS = dyn_cast<ConstantStruct>(CPV)) {
+ const std::vector<Use> &Ops = CPS->getValues();
+ std::vector<Constant*> Operands(Ops.size());
for (unsigned i = 0; i < Ops.size(); ++i)
Operands[i] =
- cast<ConstPoolVal>(RemapOperand(Ops[i], LocalMap, GlobalMap));
- Result = ConstPoolStruct::get(cast<StructType>(CPS->getType()), Operands);
- } else if (isa<ConstPoolPointerNull>(CPV)) {
- Result = CPV;
- } else if (ConstPoolPointerRef *CPR = dyn_cast<ConstPoolPointerRef>(CPV)) {
+ cast<Constant>(RemapOperand(Ops[i], LocalMap, GlobalMap));
+ Result = ConstantStruct::get(cast<StructType>(CPS->getType()), Operands);
+ } else if (isa<ConstantPointerNull>(CPV)) {
+ Result = const_cast<Constant*>(CPV);
+ } else if (const ConstantPointerRef *CPR =
+ dyn_cast<ConstantPointerRef>(CPV)) {
Value *V = RemapOperand(CPR->getValue(), LocalMap, GlobalMap);
- Result = ConstPoolPointerRef::get(cast<GlobalValue>(V));
+ Result = ConstantPointerRef::get(cast<GlobalValue>(V));
+ } else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CPV)) {
+ if (CE->getOpcode() == Instruction::GetElementPtr) {
+ Value *Ptr = RemapOperand(CE->getOperand(0), LocalMap, GlobalMap);
+ std::vector<Constant*> Indices;
+ Indices.reserve(CE->getNumOperands()-1);
+ for (unsigned i = 1, e = CE->getNumOperands(); i != e; ++i)
+ Indices.push_back(cast<Constant>(RemapOperand(CE->getOperand(i),
+ LocalMap, GlobalMap)));
+
+ Result = ConstantExpr::getGetElementPtr(cast<Constant>(Ptr), Indices);
+ } else if (CE->getNumOperands() == 1) {
+ // Cast instruction
+ assert(CE->getOpcode() == Instruction::Cast);
+ Value *V = RemapOperand(CE->getOperand(0), LocalMap, GlobalMap);
+ Result = ConstantExpr::getCast(cast<Constant>(V), CE->getType());
+ } else if (CE->getOpcode() == Instruction::Shl ||
+ CE->getOpcode() == Instruction::Shr) { // Shift
+ Value *V1 = RemapOperand(CE->getOperand(0), LocalMap, GlobalMap);
+ Value *V2 = RemapOperand(CE->getOperand(1), LocalMap, GlobalMap);
+ Result = ConstantExpr::getShift(CE->getOpcode(), cast<Constant>(V1),
+ cast<Constant>(V2));
+ } else if (CE->getNumOperands() == 2) {
+ // Binary operator...
+ Value *V1 = RemapOperand(CE->getOperand(0), LocalMap, GlobalMap);
+ Value *V2 = RemapOperand(CE->getOperand(1), LocalMap, GlobalMap);
+
+ Result = ConstantExpr::get(CE->getOpcode(), cast<Constant>(V1),
+ cast<Constant>(V2));
+ } else {
+ assert(0 && "Unknown constant expr type!");
+ }
+
} else {
assert(0 && "Unknown type of derived type constant value!");
}
// Cache the mapping in our local map structure...
- LocalMap.insert(make_pair(In, CPV));
+ if (GlobalMap)
+ GlobalMap->insert(std::make_pair(In, Result));
+ else
+ LocalMap.insert(std::make_pair(In, Result));
return Result;
}
- cerr << "XXX LocalMap: \n";
+ std::cerr << "XXX LocalMap: \n";
PrintMap(LocalMap);
if (GlobalMap) {
- cerr << "XXX GlobalMap: \n";
+ std::cerr << "XXX GlobalMap: \n";
PrintMap(*GlobalMap);
}
- cerr << "Couldn't remap value: " << (void*)In << " " << In << endl;
+ std::cerr << "Couldn't remap value: " << (void*)In << " " << *In << "\n";
assert(0 && "Couldn't remap value!");
return 0;
}
+/// FindGlobalNamed - Look in the specified symbol table for a global with the
+/// specified name and type. If an exactly matching global does not exist, see
+/// if there is a global which is "type compatible" with the specified
+/// name/type. This allows us to resolve things like '%x = global int*' with
+/// '%x = global opaque*'.
+///
+static GlobalValue *FindGlobalNamed(const std::string &Name, const Type *Ty,
+ SymbolTable *ST) {
+ // See if an exact match exists in the symbol table...
+ if (Value *V = ST->lookup(Ty, Name)) return cast<GlobalValue>(V);
+
+ // It doesn't exist exactly, scan through all of the type planes in the symbol
+ // table, checking each of them for a type-compatible version.
+ //
+ for (SymbolTable::iterator I = ST->begin(), E = ST->end(); I != E; ++I)
+ if (I->first != Type::TypeTy) {
+ SymbolTable::VarMap &VM = I->second;
+
+ // Does this type plane contain an entry with the specified name?
+ SymbolTable::type_iterator TI = VM.find(Name);
+ if (TI != VM.end()) {
+ //
+ // Ensure that this type if placed correctly into the symbol table.
+ //
+ assert(TI->second->getType() == I->first && "Type conflict!");
+
+ //
+ // Save a reference to the new type. Resolving the type can modify the
+ // symbol table, invalidating the TI variable.
+ //
+ Value *ValPtr = TI->second;
+
+ //
+ // Determine whether we can fold the two types together, resolving them.
+ // If so, we can use this value.
+ //
+ if (!RecursiveResolveTypes(Ty, I->first, ST, ""))
+ return cast<GlobalValue>(ValPtr);
+ }
+ }
+ return 0; // Otherwise, nothing could be found.
+}
+
// LinkGlobals - Loop through the global variables in the src module and merge
-// them into the dest module...
+// them into the dest module.
//
static bool LinkGlobals(Module *Dest, const Module *Src,
- map<const Value*, Value*> &ValueMap, string *Err = 0) {
+ std::map<const Value*, Value*> &ValueMap,
+ std::multimap<std::string, GlobalVariable *> &AppendingVars,
+ std::string *Err) {
// We will need a module level symbol table if the src module has a module
// level symbol table...
- SymbolTable *ST = Src->getSymbolTable() ? Dest->getSymbolTableSure() : 0;
+ SymbolTable *ST = (SymbolTable*)&Dest->getSymbolTable();
// Loop over all of the globals in the src module, mapping them over as we go
//
for (Module::const_giterator I = Src->gbegin(), E = Src->gend(); I != E; ++I){
- const GlobalVariable *SGV = *I;
- Value *V;
-
- // If the global variable has a name, and that name is already in use in the
- // Dest module, make sure that the name is a compatible global variable...
- //
- if (SGV->hasName() && (V = ST->lookup(SGV->getType(), SGV->getName()))) {
- // The same named thing is a global variable, because the only two things
- // that may be in a module level symbol table are Global Vars and Methods,
- // and they both have distinct, nonoverlapping, possible types.
+ const GlobalVariable *SGV = I;
+ GlobalVariable *DGV = 0;
+ if (SGV->hasName()) {
+ // A same named thing is a global variable, because the only two things
+ // that may be in a module level symbol table are Global Vars and
+ // Functions, and they both have distinct, nonoverlapping, possible types.
//
- GlobalVariable *DGV = cast<GlobalVariable>(V);
+ DGV = cast_or_null<GlobalVariable>(FindGlobalNamed(SGV->getName(),
+ SGV->getType(), ST));
+ }
- // Check to see if the two GV's have the same Const'ness...
- if (SGV->isConstant() != DGV->isConstant())
- return Error(Err, "Global Variable Collision on '" +
- SGV->getType()->getDescription() + "':%" + SGV->getName() +
- " - Global variables differ in const'ness");
+ assert(SGV->hasInitializer() || SGV->hasExternalLinkage() &&
+ "Global must either be external or have an initializer!");
- // Okay, everything is cool, remember the mapping...
- ValueMap.insert(make_pair(SGV, DGV));
- } else {
+ bool SGExtern = SGV->isExternal();
+ bool DGExtern = DGV ? DGV->isExternal() : false;
+
+ if (!DGV || DGV->hasInternalLinkage() || SGV->hasInternalLinkage()) {
// No linking to be performed, simply create an identical version of the
// symbol over in the dest module... the initializer will be filled in
// later by LinkGlobalInits...
//
- GlobalVariable *DGV =
- new GlobalVariable(SGV->getType()->getValueType(), SGV->isConstant(),
- 0, SGV->getName());
+ GlobalVariable *NewDGV =
+ new GlobalVariable(SGV->getType()->getElementType(),
+ SGV->isConstant(), SGV->getLinkage(), /*init*/0,
+ SGV->getName(), Dest);
+
+ // If the LLVM runtime renamed the global, but it is an externally visible
+ // symbol, DGV must be an existing global with internal linkage. Rename
+ // it.
+ if (NewDGV->getName() != SGV->getName() && !NewDGV->hasInternalLinkage()){
+ assert(DGV && DGV->getName() == SGV->getName() &&
+ DGV->hasInternalLinkage());
+ DGV->setName("");
+ NewDGV->setName(SGV->getName()); // Force the name back
+ DGV->setName(SGV->getName()); // This will cause a renaming
+ assert(NewDGV->getName() == SGV->getName() &&
+ DGV->getName() != SGV->getName());
+ }
+
+ // Make sure to remember this mapping...
+ ValueMap.insert(std::make_pair(SGV, NewDGV));
+ if (SGV->hasAppendingLinkage())
+ // Keep track that this is an appending variable...
+ AppendingVars.insert(std::make_pair(SGV->getName(), NewDGV));
+
+ } else if (SGV->isExternal()) {
+ // If SGV is external or if both SGV & DGV are external.. Just link the
+ // external globals, we aren't adding anything.
+ ValueMap.insert(std::make_pair(SGV, DGV));
+
+ } else if (DGV->isExternal()) { // If DGV is external but SGV is not...
+ ValueMap.insert(std::make_pair(SGV, DGV));
+ DGV->setLinkage(SGV->getLinkage()); // Inherit linkage!
+ } else if (SGV->hasWeakLinkage() || SGV->hasLinkOnceLinkage()) {
+ // At this point we know that DGV has LinkOnce, Appending, Weak, or
+ // External linkage. If DGV is Appending, this is an error.
+ if (DGV->hasAppendingLinkage())
+ return Error(Err, "Linking globals named '" + SGV->getName() +
+ " ' with 'weak' and 'appending' linkage is not allowed!");
+
+ if (SGV->isConstant() != DGV->isConstant())
+ return Error(Err, "Global Variable Collision on '" +
+ SGV->getType()->getDescription() + " %" + SGV->getName() +
+ "' - Global variables differ in const'ness");
+
+ // Otherwise, just perform the link.
+ ValueMap.insert(std::make_pair(SGV, DGV));
+
+ // Linkonce+Weak = Weak
+ if (DGV->hasLinkOnceLinkage() && SGV->hasWeakLinkage())
+ DGV->setLinkage(SGV->getLinkage());
- // Add the new global to the dest module
- Dest->getGlobalList().push_back(DGV);
+ } else if (DGV->hasWeakLinkage() || DGV->hasLinkOnceLinkage()) {
+ // At this point we know that SGV has LinkOnce, Appending, or External
+ // linkage. If SGV is Appending, this is an error.
+ if (SGV->hasAppendingLinkage())
+ return Error(Err, "Linking globals named '" + SGV->getName() +
+ " ' with 'weak' and 'appending' linkage is not allowed!");
+
+ if (SGV->isConstant() != DGV->isConstant())
+ return Error(Err, "Global Variable Collision on '" +
+ SGV->getType()->getDescription() + " %" + SGV->getName() +
+ "' - Global variables differ in const'ness");
+
+ if (!SGV->hasLinkOnceLinkage())
+ DGV->setLinkage(SGV->getLinkage()); // Inherit linkage!
+ ValueMap.insert(std::make_pair(SGV, DGV));
+
+ } else if (SGV->getLinkage() != DGV->getLinkage()) {
+ return Error(Err, "Global variables named '" + SGV->getName() +
+ "' have different linkage specifiers!");
+ } else if (SGV->hasExternalLinkage()) {
+ // Allow linking two exactly identical external global variables...
+ if (SGV->isConstant() != DGV->isConstant())
+ return Error(Err, "Global Variable Collision on '" +
+ SGV->getType()->getDescription() + " %" + SGV->getName() +
+ "' - Global variables differ in const'ness");
+
+ if (SGV->getInitializer() != DGV->getInitializer())
+ return Error(Err, "Global Variable Collision on '" +
+ SGV->getType()->getDescription() + " %" + SGV->getName() +
+ "' - External linkage globals have different initializers");
+
+ ValueMap.insert(std::make_pair(SGV, DGV));
+ } else if (SGV->hasAppendingLinkage()) {
+ // No linking is performed yet. Just insert a new copy of the global, and
+ // keep track of the fact that it is an appending variable in the
+ // AppendingVars map. The name is cleared out so that no linkage is
+ // performed.
+ GlobalVariable *NewDGV =
+ new GlobalVariable(SGV->getType()->getElementType(),
+ SGV->isConstant(), SGV->getLinkage(), /*init*/0,
+ "", Dest);
// Make sure to remember this mapping...
- ValueMap.insert(make_pair(SGV, DGV));
+ ValueMap.insert(std::make_pair(SGV, NewDGV));
+
+ // Keep track that this is an appending variable...
+ AppendingVars.insert(std::make_pair(SGV->getName(), NewDGV));
+ } else {
+ assert(0 && "Unknown linkage!");
}
}
return false;
// globals that may be referenced are in Dest.
//
static bool LinkGlobalInits(Module *Dest, const Module *Src,
- map<const Value*, Value*> &ValueMap,
- string *Err = 0) {
+ std::map<const Value*, Value*> &ValueMap,
+ std::string *Err) {
// Loop over all of the globals in the src module, mapping them over as we go
//
for (Module::const_giterator I = Src->gbegin(), E = Src->gend(); I != E; ++I){
- const GlobalVariable *SGV = *I;
+ const GlobalVariable *SGV = I;
if (SGV->hasInitializer()) { // Only process initialized GV's
// Figure out what the initializer looks like in the dest module...
- ConstPoolVal *DInit =
- cast<ConstPoolVal>(RemapOperand(SGV->getInitializer(), ValueMap));
+ Constant *SInit =
+ cast<Constant>(RemapOperand(SGV->getInitializer(), ValueMap, 0));
GlobalVariable *DGV = cast<GlobalVariable>(ValueMap[SGV]);
if (DGV->hasInitializer()) {
- if (DGV->getInitializer() != DInit)
- return Error(Err, "Global Variable Collision on '" +
- SGV->getType()->getDescription() + "':%" +SGV->getName()+
- " - Global variables have different initializers");
+ assert(SGV->getLinkage() == DGV->getLinkage());
+ if (SGV->hasExternalLinkage()) {
+ if (DGV->getInitializer() != SInit)
+ return Error(Err, "Global Variable Collision on '" +
+ SGV->getType()->getDescription() +"':%"+SGV->getName()+
+ " - Global variables have different initializers");
+ } else if (DGV->hasLinkOnceLinkage() || DGV->hasWeakLinkage()) {
+ // Nothing is required, mapped values will take the new global
+ // automatically.
+ } else if (DGV->hasAppendingLinkage()) {
+ assert(0 && "Appending linkage unimplemented!");
+ } else {
+ assert(0 && "Unknown linkage!");
+ }
} else {
// Copy the initializer over now...
- DGV->setInitializer(DInit);
+ DGV->setInitializer(SInit);
}
}
}
return false;
}
-// LinkMethodProtos - Link the methods together between the two modules, without
-// doing method bodies... this just adds external method prototypes to the Dest
-// method...
+// LinkFunctionProtos - Link the functions together between the two modules,
+// without doing function bodies... this just adds external function prototypes
+// to the Dest function...
//
-static bool LinkMethodProtos(Module *Dest, const Module *Src,
- map<const Value*, Value*> &ValueMap,
- string *Err = 0) {
- // We will need a module level symbol table if the src module has a module
- // level symbol table...
- SymbolTable *ST = Src->getSymbolTable() ? Dest->getSymbolTableSure() : 0;
+static bool LinkFunctionProtos(Module *Dest, const Module *Src,
+ std::map<const Value*, Value*> &ValueMap,
+ std::string *Err) {
+ SymbolTable *ST = (SymbolTable*)&Dest->getSymbolTable();
- // Loop over all of the methods in the src module, mapping them over as we go
+ // Loop over all of the functions in the src module, mapping them over as we
+ // go
//
for (Module::const_iterator I = Src->begin(), E = Src->end(); I != E; ++I) {
- const Method *SM = *I; // SrcMethod
- Value *V;
-
- // If the method has a name, and that name is already in use in the
- // Dest module, make sure that the name is a compatible method...
- //
- if (SM->hasName() && (V = ST->lookup(SM->getType(), SM->getName()))) {
- // The same named thing is a Method, because the only two things
- // that may be in a module level symbol table are Global Vars and Methods,
- // and they both have distinct, nonoverlapping, possible types.
+ const Function *SF = I; // SrcFunction
+ Function *DF = 0;
+ if (SF->hasName())
+ // The same named thing is a Function, because the only two things
+ // that may be in a module level symbol table are Global Vars and
+ // Functions, and they both have distinct, nonoverlapping, possible types.
//
- Method *DM = cast<Method>(V); // DestMethod
-
- // Check to make sure the method is not defined in both modules...
- if (!SM->isExternal() && !DM->isExternal())
- return Error(Err, "Method '" +
- SM->getMethodType()->getDescription() + "':\"" +
- SM->getName() + "\" - Method is already defined!");
-
- // Otherwise, just remember this mapping...
- ValueMap.insert(make_pair(SM, DM));
- } else {
- // Method does not already exist, simply insert an external method
- // signature identical to SM into the dest module...
- Method *DM = new Method(SM->getMethodType(), SM->getName());
-
- // Add the method signature to the dest module...
- Dest->getMethodList().push_back(DM);
+ DF = cast_or_null<Function>(FindGlobalNamed(SF->getName(), SF->getType(),
+ ST));
+
+ if (!DF || SF->hasInternalLinkage() || DF->hasInternalLinkage()) {
+ // Function does not already exist, simply insert an function signature
+ // identical to SF into the dest module...
+ Function *NewDF = new Function(SF->getFunctionType(), SF->getLinkage(),
+ SF->getName(), Dest);
+
+ // If the LLVM runtime renamed the function, but it is an externally
+ // visible symbol, DF must be an existing function with internal linkage.
+ // Rename it.
+ if (NewDF->getName() != SF->getName() && !NewDF->hasInternalLinkage()) {
+ assert(DF && DF->getName() == SF->getName() &&DF->hasInternalLinkage());
+ DF->setName("");
+ NewDF->setName(SF->getName()); // Force the name back
+ DF->setName(SF->getName()); // This will cause a renaming
+ assert(NewDF->getName() == SF->getName() &&
+ DF->getName() != SF->getName());
+ }
// ... and remember this mapping...
- ValueMap.insert(make_pair(SM, DM));
+ ValueMap.insert(std::make_pair(SF, NewDF));
+ } else if (SF->isExternal()) {
+ // If SF is external or if both SF & DF are external.. Just link the
+ // external functions, we aren't adding anything.
+ ValueMap.insert(std::make_pair(SF, DF));
+ } else if (DF->isExternal()) { // If DF is external but SF is not...
+ // Link the external functions, update linkage qualifiers
+ ValueMap.insert(std::make_pair(SF, DF));
+ DF->setLinkage(SF->getLinkage());
+
+ } else if (SF->hasWeakLinkage() || SF->hasLinkOnceLinkage()) {
+ // At this point we know that DF has LinkOnce, Weak, or External linkage.
+ ValueMap.insert(std::make_pair(SF, DF));
+
+ // Linkonce+Weak = Weak
+ if (DF->hasLinkOnceLinkage() && SF->hasWeakLinkage())
+ DF->setLinkage(SF->getLinkage());
+
+ } else if (DF->hasWeakLinkage() || DF->hasLinkOnceLinkage()) {
+ // At this point we know that SF has LinkOnce or External linkage.
+ ValueMap.insert(std::make_pair(SF, DF));
+ if (!SF->hasLinkOnceLinkage()) // Don't inherit linkonce linkage
+ DF->setLinkage(SF->getLinkage());
+
+ } else if (SF->getLinkage() != DF->getLinkage()) {
+ return Error(Err, "Functions named '" + SF->getName() +
+ "' have different linkage specifiers!");
+ } else if (SF->hasExternalLinkage()) {
+ // The function is defined in both modules!!
+ return Error(Err, "Function '" +
+ SF->getFunctionType()->getDescription() + "':\"" +
+ SF->getName() + "\" - Function is already defined!");
+ } else {
+ assert(0 && "Unknown linkage configuration found!");
}
}
return false;
}
-// LinkMethodBody - Copy the source method over into the dest method and fix up
-// references to values. At this point we know that Dest is an external method,
-// and that Src is not.
+// LinkFunctionBody - Copy the source function over into the dest function and
+// fix up references to values. At this point we know that Dest is an external
+// function, and that Src is not.
//
-static bool LinkMethodBody(Method *Dest, const Method *Src,
- const map<const Value*, Value*> &GlobalMap,
- string *Err = 0) {
+static bool LinkFunctionBody(Function *Dest, const Function *Src,
+ std::map<const Value*, Value*> &GlobalMap,
+ std::string *Err) {
assert(Src && Dest && Dest->isExternal() && !Src->isExternal());
- map<const Value*, Value*> LocalMap; // Map for method local values
-
- // Go through and convert method arguments over...
- for (Method::ArgumentListType::const_iterator
- I = Src->getArgumentList().begin(),
- E = Src->getArgumentList().end(); I != E; ++I) {
- const MethodArgument *SMA = *I;
+ std::map<const Value*, Value*> LocalMap; // Map for function local values
- // Create the new method argument and add to the dest method...
- MethodArgument *DMA = new MethodArgument(SMA->getType(), SMA->getName());
- Dest->getArgumentList().push_back(DMA);
+ // Go through and convert function arguments over...
+ Function::aiterator DI = Dest->abegin();
+ for (Function::const_aiterator I = Src->abegin(), E = Src->aend();
+ I != E; ++I, ++DI) {
+ DI->setName(I->getName()); // Copy the name information over...
// Add a mapping to our local map
- LocalMap.insert(make_pair(SMA, DMA));
+ LocalMap.insert(std::make_pair(I, DI));
}
// Loop over all of the basic blocks, copying the instructions over...
//
- for (Method::const_iterator I = Src->begin(), E = Src->end(); I != E; ++I) {
- const BasicBlock *SBB = *I;
-
- // Create new basic block and add to mapping and the Dest method...
- BasicBlock *DBB = new BasicBlock(SBB->getName(), Dest);
- LocalMap.insert(make_pair(SBB, DBB));
+ for (Function::const_iterator I = Src->begin(), E = Src->end(); I != E; ++I) {
+ // Create new basic block and add to mapping and the Dest function...
+ BasicBlock *DBB = new BasicBlock(I->getName(), Dest);
+ LocalMap.insert(std::make_pair(I, DBB));
// Loop over all of the instructions in the src basic block, copying them
// over. Note that this is broken in a strict sense because the cloned
// the remapped values. In our case, however, we will not get caught and
// so we can delay patching the values up until later...
//
- for (BasicBlock::const_iterator II = SBB->begin(), IE = SBB->end();
+ for (BasicBlock::const_iterator II = I->begin(), IE = I->end();
II != IE; ++II) {
- const Instruction *SI = *II;
- Instruction *DI = SI->clone();
- DI->setName(SI->getName());
+ Instruction *DI = II->clone();
+ DI->setName(II->getName());
DBB->getInstList().push_back(DI);
- LocalMap.insert(make_pair(SI, DI));
+ LocalMap.insert(std::make_pair(II, DI));
}
}
- // At this point, all of the instructions and values of the method are now
- // copied over. The only problem is that they are still referencing values
- // in the Source method as operands. Loop through all of the operands of the
- // methods and patch them up to point to the local versions...
+ // At this point, all of the instructions and values of the function are now
+ // copied over. The only problem is that they are still referencing values in
+ // the Source function as operands. Loop through all of the operands of the
+ // functions and patch them up to point to the local versions...
//
- for (Method::inst_iterator I = Dest->inst_begin(), E = Dest->inst_end();
- I != E; ++I) {
- Instruction *Inst = *I;
-
- for (Instruction::op_iterator OI = Inst->op_begin(), OE = Inst->op_end();
- OI != OE; ++OI)
- *OI = RemapOperand(*OI, LocalMap, &GlobalMap);
- }
+ for (Function::iterator BB = Dest->begin(), BE = Dest->end(); BB != BE; ++BB)
+ for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I)
+ for (Instruction::op_iterator OI = I->op_begin(), OE = I->op_end();
+ OI != OE; ++OI)
+ *OI = RemapOperand(*OI, LocalMap, &GlobalMap);
return false;
}
-// LinkMethodBodies - Link in the method bodies that are defined in the source
-// module into the DestModule. This consists basically of copying the method
-// over and fixing up references to values.
+// LinkFunctionBodies - Link in the function bodies that are defined in the
+// source module into the DestModule. This consists basically of copying the
+// function over and fixing up references to values.
//
-static bool LinkMethodBodies(Module *Dest, const Module *Src,
- map<const Value*, Value*> &ValueMap,
- string *Err = 0) {
+static bool LinkFunctionBodies(Module *Dest, const Module *Src,
+ std::map<const Value*, Value*> &ValueMap,
+ std::string *Err) {
- // Loop over all of the methods in the src module, mapping them over as we go
+ // Loop over all of the functions in the src module, mapping them over as we
+ // go
//
- for (Module::const_iterator I = Src->begin(), E = Src->end(); I != E; ++I) {
- const Method *SM = *I; // Source Method
- if (!SM->isExternal()) { // No body if method is external
- Method *DM = cast<Method>(ValueMap[SM]); // Destination method
-
- // DM not external SM external?
- if (!DM->isExternal()) {
- if (Err)
- *Err = "Method '" + (SM->hasName() ? SM->getName() : string("")) +
- "' body multiply defined!";
- return true;
+ for (Module::const_iterator SF = Src->begin(), E = Src->end(); SF != E; ++SF){
+ if (!SF->isExternal()) { // No body if function is external
+ Function *DF = cast<Function>(ValueMap[SF]); // Destination function
+
+ // DF not external SF external?
+ if (DF->isExternal()) {
+ // Only provide the function body if there isn't one already.
+ if (LinkFunctionBody(DF, SF, ValueMap, Err))
+ return true;
}
-
- if (LinkMethodBody(DM, SM, ValueMap, Err)) return true;
}
}
return false;
}
+// LinkAppendingVars - If there were any appending global variables, link them
+// together now. Return true on error.
+//
+static bool LinkAppendingVars(Module *M,
+ std::multimap<std::string, GlobalVariable *> &AppendingVars,
+ std::string *ErrorMsg) {
+ if (AppendingVars.empty()) return false; // Nothing to do.
+
+ // Loop over the multimap of appending vars, processing any variables with the
+ // same name, forming a new appending global variable with both of the
+ // initializers merged together, then rewrite references to the old variables
+ // and delete them.
+ //
+ std::vector<Constant*> Inits;
+ while (AppendingVars.size() > 1) {
+ // Get the first two elements in the map...
+ std::multimap<std::string,
+ GlobalVariable*>::iterator Second = AppendingVars.begin(), First=Second++;
+
+ // If the first two elements are for different names, there is no pair...
+ // Otherwise there is a pair, so link them together...
+ if (First->first == Second->first) {
+ GlobalVariable *G1 = First->second, *G2 = Second->second;
+ const ArrayType *T1 = cast<ArrayType>(G1->getType()->getElementType());
+ const ArrayType *T2 = cast<ArrayType>(G2->getType()->getElementType());
+
+ // Check to see that they two arrays agree on type...
+ if (T1->getElementType() != T2->getElementType())
+ return Error(ErrorMsg,
+ "Appending variables with different element types need to be linked!");
+ if (G1->isConstant() != G2->isConstant())
+ return Error(ErrorMsg,
+ "Appending variables linked with different const'ness!");
+
+ unsigned NewSize = T1->getNumElements() + T2->getNumElements();
+ ArrayType *NewType = ArrayType::get(T1->getElementType(), NewSize);
+
+ // Create the new global variable...
+ GlobalVariable *NG =
+ new GlobalVariable(NewType, G1->isConstant(), G1->getLinkage(),
+ /*init*/0, First->first, M);
+
+ // Merge the initializer...
+ Inits.reserve(NewSize);
+ ConstantArray *I = cast<ConstantArray>(G1->getInitializer());
+ for (unsigned i = 0, e = T1->getNumElements(); i != e; ++i)
+ Inits.push_back(cast<Constant>(I->getValues()[i]));
+ I = cast<ConstantArray>(G2->getInitializer());
+ for (unsigned i = 0, e = T2->getNumElements(); i != e; ++i)
+ Inits.push_back(cast<Constant>(I->getValues()[i]));
+ NG->setInitializer(ConstantArray::get(NewType, Inits));
+ Inits.clear();
+
+ // Replace any uses of the two global variables with uses of the new
+ // global...
+
+ // FIXME: This should rewrite simple/straight-forward uses such as
+ // getelementptr instructions to not use the Cast!
+ ConstantPointerRef *NGCP = ConstantPointerRef::get(NG);
+ G1->replaceAllUsesWith(ConstantExpr::getCast(NGCP, G1->getType()));
+ G2->replaceAllUsesWith(ConstantExpr::getCast(NGCP, G2->getType()));
+
+ // Remove the two globals from the module now...
+ M->getGlobalList().erase(G1);
+ M->getGlobalList().erase(G2);
+
+ // Put the new global into the AppendingVars map so that we can handle
+ // linking of more than two vars...
+ Second->second = NG;
+ }
+ AppendingVars.erase(First);
+ }
+
+ return false;
+}
// LinkModules - This function links two modules together, with the resulting
// the problem. Upon failure, the Dest module could be in a modified state, and
// shouldn't be relied on to be consistent.
//
-bool LinkModules(Module *Dest, const Module *Src, string *ErrorMsg = 0) {
+bool LinkModules(Module *Dest, const Module *Src, std::string *ErrorMsg) {
+ if (Dest->getEndianness() == Module::AnyEndianness)
+ Dest->setEndianness(Src->getEndianness());
+ if (Dest->getPointerSize() == Module::AnyPointerSize)
+ Dest->setPointerSize(Src->getPointerSize());
+
+ if (Src->getEndianness() != Module::AnyEndianness &&
+ Dest->getEndianness() != Src->getEndianness())
+ std::cerr << "WARNING: Linking two modules of different endianness!\n";
+ if (Src->getPointerSize() != Module::AnyPointerSize &&
+ Dest->getPointerSize() != Src->getPointerSize())
+ std::cerr << "WARNING: Linking two modules of different pointer size!\n";
// LinkTypes - Go through the symbol table of the Src module and see if any
// types are named in the src module that are not named in the Dst module.
// ValueMap - Mapping of values from what they used to be in Src, to what they
// are now in Dest.
//
- map<const Value*, Value*> ValueMap;
+ std::map<const Value*, Value*> ValueMap;
+
+ // AppendingVars - Keep track of global variables in the destination module
+ // with appending linkage. After the module is linked together, they are
+ // appended and the module is rewritten.
+ //
+ std::multimap<std::string, GlobalVariable *> AppendingVars;
+
+ // Add all of the appending globals already in the Dest module to
+ // AppendingVars.
+ for (Module::giterator I = Dest->gbegin(), E = Dest->gend(); I != E; ++I)
+ if (I->hasAppendingLinkage())
+ AppendingVars.insert(std::make_pair(I->getName(), I));
- // Insert all of the globals in src into the Dest module... without
- // initializers
- if (LinkGlobals(Dest, Src, ValueMap, ErrorMsg)) return true;
+ // Insert all of the globals in src into the Dest module... without linking
+ // initializers (which could refer to functions not yet mapped over).
+ //
+ if (LinkGlobals(Dest, Src, ValueMap, AppendingVars, ErrorMsg)) return true;
+
+ // Link the functions together between the two modules, without doing function
+ // bodies... this just adds external function prototypes to the Dest
+ // function... We do this so that when we begin processing function bodies,
+ // all of the global values that may be referenced are available in our
+ // ValueMap.
+ //
+ if (LinkFunctionProtos(Dest, Src, ValueMap, ErrorMsg)) return true;
// Update the initializers in the Dest module now that all globals that may
// be referenced are in Dest.
//
if (LinkGlobalInits(Dest, Src, ValueMap, ErrorMsg)) return true;
- // Link the methods together between the two modules, without doing method
- // bodies... this just adds external method prototypes to the Dest method...
- // We do this so that when we begin processing method bodies, all of the
- // global values that may be referenced are available in our ValueMap.
+ // Link in the function bodies that are defined in the source module into the
+ // DestModule. This consists basically of copying the function over and
+ // fixing up references to values.
//
- if (LinkMethodProtos(Dest, Src, ValueMap, ErrorMsg)) return true;
+ if (LinkFunctionBodies(Dest, Src, ValueMap, ErrorMsg)) return true;
- // Link in the method bodies that are defined in the source module into the
- // DestModule. This consists basically of copying the method over and fixing
- // up references to values.
+ // If there were any appending global variables, link them together now.
//
- if (LinkMethodBodies(Dest, Src, ValueMap, ErrorMsg)) return true;
+ if (LinkAppendingVars(Dest, AppendingVars, ErrorMsg)) return true;
return false;
}
+} // End llvm namespace