llvm-6502/lib/Transforms/Utils/CloneModule.cpp
2014-04-25 05:29:35 +00:00

123 lines
4.7 KiB
C++

//===- CloneModule.cpp - Clone an entire module ---------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the CloneModule interface which makes a copy of an
// entire module.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/Cloning.h"
#include "llvm/IR/Constant.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Module.h"
#include "llvm/Transforms/Utils/ValueMapper.h"
using namespace llvm;
/// CloneModule - Return an exact copy of the specified module. This is not as
/// easy as it might seem because we have to worry about making copies of global
/// variables and functions, and making their (initializers and references,
/// respectively) refer to the right globals.
///
Module *llvm::CloneModule(const Module *M) {
// Create the value map that maps things from the old module over to the new
// module.
ValueToValueMapTy VMap;
return CloneModule(M, VMap);
}
Module *llvm::CloneModule(const Module *M, ValueToValueMapTy &VMap) {
// First off, we need to create the new module.
Module *New = new Module(M->getModuleIdentifier(), M->getContext());
New->setDataLayout(M->getDataLayout());
New->setTargetTriple(M->getTargetTriple());
New->setModuleInlineAsm(M->getModuleInlineAsm());
// Loop over all of the global variables, making corresponding globals in the
// new module. Here we add them to the VMap and to the new Module. We
// don't worry about attributes or initializers, they will come later.
//
for (Module::const_global_iterator I = M->global_begin(), E = M->global_end();
I != E; ++I) {
GlobalVariable *GV = new GlobalVariable(*New,
I->getType()->getElementType(),
I->isConstant(), I->getLinkage(),
(Constant*) nullptr, I->getName(),
(GlobalVariable*) nullptr,
I->getThreadLocalMode(),
I->getType()->getAddressSpace());
GV->copyAttributesFrom(I);
VMap[I] = GV;
}
// Loop over the functions in the module, making external functions as before
for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I) {
Function *NF =
Function::Create(cast<FunctionType>(I->getType()->getElementType()),
I->getLinkage(), I->getName(), New);
NF->copyAttributesFrom(I);
VMap[I] = NF;
}
// Loop over the aliases in the module
for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end();
I != E; ++I) {
GlobalAlias *GA = new GlobalAlias(I->getType(), I->getLinkage(),
I->getName(), nullptr, New);
GA->copyAttributesFrom(I);
VMap[I] = GA;
}
// Now that all of the things that global variable initializer can refer to
// have been created, loop through and copy the global variable referrers
// over... We also set the attributes on the global now.
//
for (Module::const_global_iterator I = M->global_begin(), E = M->global_end();
I != E; ++I) {
GlobalVariable *GV = cast<GlobalVariable>(VMap[I]);
if (I->hasInitializer())
GV->setInitializer(MapValue(I->getInitializer(), VMap));
}
// Similarly, copy over function bodies now...
//
for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I) {
Function *F = cast<Function>(VMap[I]);
if (!I->isDeclaration()) {
Function::arg_iterator DestI = F->arg_begin();
for (Function::const_arg_iterator J = I->arg_begin(); J != I->arg_end();
++J) {
DestI->setName(J->getName());
VMap[J] = DestI++;
}
SmallVector<ReturnInst*, 8> Returns; // Ignore returns cloned.
CloneFunctionInto(F, I, VMap, /*ModuleLevelChanges=*/true, Returns);
}
}
// And aliases
for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end();
I != E; ++I) {
GlobalAlias *GA = cast<GlobalAlias>(VMap[I]);
if (const Constant *C = I->getAliasee())
GA->setAliasee(MapValue(C, VMap));
}
// And named metadata....
for (Module::const_named_metadata_iterator I = M->named_metadata_begin(),
E = M->named_metadata_end(); I != E; ++I) {
const NamedMDNode &NMD = *I;
NamedMDNode *NewNMD = New->getOrInsertNamedMetadata(NMD.getName());
for (unsigned i = 0, e = NMD.getNumOperands(); i != e; ++i)
NewNMD->addOperand(MapValue(NMD.getOperand(i), VMap));
}
return New;
}