Moved to lib/VMCore

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@14348 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 0 insertions, 927 deletions

diff --git a/lib/Transforms/Utils/Linker.cpp b/lib/Transforms/Utils/Linker.cpp
deleted file mode 100644
index 00906a4..0000000
--- a/lib/Transforms/Utils/Linker.cpp
+++ /dev/null
@@ -1,927 +0,0 @@
-//===- 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 functions between two modules
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/Transforms/Utils/Linker.h"
-#include "llvm/Constants.h"
-#include "llvm/DerivedTypes.h"
-#include "llvm/Module.h"
-#include "llvm/SymbolTable.h"
-#include "llvm/iOther.h"
-#include "llvm/Assembly/Writer.h"
-using 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(std::string *E, const std::string &Message) {
-  if (E) *E = Message;
-  return true;
-}
-
-//
-// 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->getTypeID() != SrcTyT->getTypeID()) return true;
-
-  // Otherwise, resolve the used type used by this derived type...
-  switch (DestTyT->getTypeID()) {
-  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, std::string *Err) {
-  SymbolTable       *DestST = &Dest->getSymbolTable();
-  const SymbolTable *SrcST  = &Src->getSymbolTable();
-
-  // Look for a type plane for Type's...
-  SymbolTable::type_const_iterator TI = SrcST->type_begin();
-  SymbolTable::type_const_iterator TE = SrcST->type_end();
-  if (TI == TE) 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;
-
-  for ( ; TI != TE; ++TI ) {
-    const std::string &Name = TI->first;
-    Type *RHS = TI->second;
-
-    // Check to see if this type name is already in the dest module...
-    Type *Entry = DestST->lookupType(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 = SrcST->lookupType(Name);
-      Type *T2 = DestST->lookupType(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(SrcST->lookupType(Name));
-        PATypeHolder T2(DestST->lookupType(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 = SrcST->lookupType(Name);
-        const Type *T2 = DestST->lookupType(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 std::map<const Value*, Value*> &M) {
-  for (std::map<const Value*, Value*>::const_iterator I = M.begin(), E =M.end();
-       I != E; ++I) {
-    std::cerr << " Fr: " << (void*)I->first << " ";
-    I->first->dump();
-    std::cerr << " To: " << (void*)I->second << " ";
-    I->second->dump();
-    std::cerr << "\n";
-  }
-}
-
-
-// RemapOperand - Use LocalMap and GlobalMap to convert references from one
-// module to another.  This is somewhat sophisticated in that it can
-// automatically handle constant references correctly as well...
-//
-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) {
-    I = GlobalMap->find(In);
-    if (I != GlobalMap->end()) return I->second;
-  }
-
-  // Check to see if it's a constant that we are interesting in transforming...
-  if (const Constant *CPV = dyn_cast<Constant>(In)) {
-    if ((!isa<DerivedType>(CPV->getType()) && !isa<ConstantExpr>(CPV)) ||
-        isa<ConstantAggregateZero>(CPV))
-      return const_cast<Constant*>(CPV);   // Simple constants stay identical...
-
-    Constant *Result = 0;
-
-    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<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<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 = 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->getNumOperands() == 3) {
-        // Select instruction
-        assert(CE->getOpcode() == Instruction::Select);
-        Value *V1 = RemapOperand(CE->getOperand(0), LocalMap, GlobalMap);
-        Value *V2 = RemapOperand(CE->getOperand(1), LocalMap, GlobalMap);
-        Value *V3 = RemapOperand(CE->getOperand(2), LocalMap, GlobalMap);
-        Result = ConstantExpr::getSelect(cast<Constant>(V1), cast<Constant>(V2),
-                                         cast<Constant>(V3));
-      } 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...
-    if (GlobalMap)
-      GlobalMap->insert(std::make_pair(In, Result));
-    else
-      LocalMap.insert(std::make_pair(In, Result));
-    return Result;
-  }
-
-  std::cerr << "XXX LocalMap: \n";
-  PrintMap(LocalMap);
-
-  if (GlobalMap) {
-    std::cerr << "XXX GlobalMap: \n";
-    PrintMap(*GlobalMap);
-  }
-
-  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::plane_iterator PI = ST->plane_begin(), PE = ST->plane_end(); 
-       PI != PE; ++PI) {
-    SymbolTable::ValueMap &VM = PI->second;
-
-    // Does this type plane contain an entry with the specified name?
-    SymbolTable::value_iterator VI = VM.find(Name);
-      if (VI != VM.end()) {
-        //
-        // Ensure that this type if placed correctly into the symbol table.
-        //
-        assert(VI->second->getType() == PI->first && "Type conflict!");
-
-        //
-        // Save a reference to the new type.  Resolving the type can modify the
-        // symbol table, invalidating the TI variable.
-        //
-        Value *ValPtr = VI->second;
-
-        //
-        // Determine whether we can fold the two types together, resolving them.
-        // If so, we can use this value.
-        //
-        if (!RecursiveResolveTypes(Ty, PI->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.
-//
-static bool LinkGlobals(Module *Dest, const Module *Src,
-                        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 = (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;
-    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.
-      // 
-      DGV = cast_or_null<GlobalVariable>(FindGlobalNamed(SGV->getName(), 
-                                                         SGV->getType(), ST));
-    }
-
-    assert(SGV->hasInitializer() || SGV->hasExternalLinkage() &&
-           "Global must either be external or have an initializer!");
-
-    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 *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());
-
-    } 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(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;
-}
-
-
-// LinkGlobalInits - Update the initializers in the Dest module now that all
-// globals that may be referenced are in Dest.
-//
-static bool LinkGlobalInits(Module *Dest, const Module *Src,
-                            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;
-
-    if (SGV->hasInitializer()) {      // Only process initialized GV's
-      // Figure out what the initializer looks like in the dest module...
-      Constant *SInit =
-        cast<Constant>(RemapOperand(SGV->getInitializer(), ValueMap, 0));
-
-      GlobalVariable *DGV = cast<GlobalVariable>(ValueMap[SGV]);    
-      if (DGV->hasInitializer()) {
-        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 (SGV->hasLinkOnceLinkage() || SGV->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(SInit);
-      }
-    }
-  }
-  return false;
-}
-
-// 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 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 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 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.
-      // 
-      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(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;
-}
-
-// 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 LinkFunctionBody(Function *Dest, const Function *Src,
-                             std::map<const Value*, Value*> &GlobalMap,
-                             std::string *Err) {
-  assert(Src && Dest && Dest->isExternal() && !Src->isExternal());
-  std::map<const Value*, Value*> LocalMap;   // Map for function local values
-
-  // 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(std::make_pair(I, DI));
-  }
-
-  // Loop over all of the basic blocks, copying the instructions over...
-  //
-  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
-    // instructions will still be referencing values in the Src module, not
-    // 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 = I->begin(), IE = I->end(); 
-         II != IE; ++II) {
-      Instruction *DI = II->clone();
-      DI->setName(II->getName());
-      DBB->getInstList().push_back(DI);
-      LocalMap.insert(std::make_pair(II, DI));
-    }
-  }
-
-  // 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 (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;
-}
-
-
-// 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 LinkFunctionBodies(Module *Dest, const Module *Src,
-                               std::map<const Value*, Value*> &ValueMap,
-                               std::string *Err) {
-
-  // Loop over all of the functions in the src module, mapping them over as we
-  // go
-  //
-  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;
-      }
-    }
-  }
-  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);
-      if (ConstantArray *I = dyn_cast<ConstantArray>(G1->getInitializer())) {
-        for (unsigned i = 0, e = T1->getNumElements(); i != e; ++i)
-          Inits.push_back(cast<Constant>(I->getValues()[i]));
-      } else {
-        assert(isa<ConstantAggregateZero>(G1->getInitializer()));
-        Constant *CV = Constant::getNullValue(T1->getElementType());
-        for (unsigned i = 0, e = T1->getNumElements(); i != e; ++i)
-          Inits.push_back(CV);
-      }
-      if (ConstantArray *I = dyn_cast<ConstantArray>(G2->getInitializer())) {
-        for (unsigned i = 0, e = T2->getNumElements(); i != e; ++i)
-          Inits.push_back(cast<Constant>(I->getValues()[i]));
-      } else {
-        assert(isa<ConstantAggregateZero>(G2->getInitializer()));
-        Constant *CV = Constant::getNullValue(T2->getElementType());
-        for (unsigned i = 0, e = T2->getNumElements(); i != e; ++i)
-          Inits.push_back(CV);
-      }
-      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
-// left module modified to be the composite of the two input modules.  If an
-// error occurs, true is returned and ErrorMsg (if not null) is set to indicate
-// the problem.  Upon failure, the Dest module could be in a modified state, and
-// shouldn't be relied on to be consistent.
-//
-bool llvm::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.
-  // Make sure there are no type name conflicts.
-  //
-  if (LinkTypes(Dest, Src, ErrorMsg)) return true;
-
-  // ValueMap - Mapping of values from what they used to be in Src, to what they
-  // are now in Dest.
-  //
-  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 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 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 (LinkFunctionBodies(Dest, Src, ValueMap, ErrorMsg)) return true;
-
-  // If there were any appending global variables, link them together now.
-  //
-  if (LinkAppendingVars(Dest, AppendingVars, ErrorMsg)) return true;
-
-  return false;
-}
-
-// vim: sw=2