1 //===- CloneModule.cpp - Clone an entire module ---------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements the CloneModule interface which makes a copy of an
11 // entire module.
12 //
13 //===----------------------------------------------------------------------===//
14
15 #include "llvm/Transforms/Utils/Cloning.h"
16 #include "llvm/Module.h"
17 #include "llvm/DerivedTypes.h"
18 #include "llvm/Constant.h"
19 #include "llvm/Transforms/Utils/ValueMapper.h"
20 using namespace llvm;
21
22 /// CloneModule - Return an exact copy of the specified module. This is not as
23 /// easy as it might seem because we have to worry about making copies of global
24 /// variables and functions, and making their (initializers and references,
25 /// respectively) refer to the right globals.
26 ///
CloneModule(const Module * M)27 Module *llvm::CloneModule(const Module *M) {
28 // Create the value map that maps things from the old module over to the new
29 // module.
30 ValueToValueMapTy VMap;
31 return CloneModule(M, VMap);
32 }
33
CloneModule(const Module * M,ValueToValueMapTy & VMap)34 Module *llvm::CloneModule(const Module *M, ValueToValueMapTy &VMap) {
35 // First off, we need to create the new module.
36 Module *New = new Module(M->getModuleIdentifier(), M->getContext());
37 New->setDataLayout(M->getDataLayout());
38 New->setTargetTriple(M->getTargetTriple());
39 New->setModuleInlineAsm(M->getModuleInlineAsm());
40
41 // Copy all of the dependent libraries over.
42 for (Module::lib_iterator I = M->lib_begin(), E = M->lib_end(); I != E; ++I)
43 New->addLibrary(*I);
44
45 // Loop over all of the global variables, making corresponding globals in the
46 // new module. Here we add them to the VMap and to the new Module. We
47 // don't worry about attributes or initializers, they will come later.
48 //
49 for (Module::const_global_iterator I = M->global_begin(), E = M->global_end();
50 I != E; ++I) {
51 GlobalVariable *GV = new GlobalVariable(*New,
52 I->getType()->getElementType(),
53 I->isConstant(), I->getLinkage(),
54 (Constant*) 0, I->getName(),
55 (GlobalVariable*) 0,
56 I->isThreadLocal(),
57 I->getType()->getAddressSpace());
58 GV->copyAttributesFrom(I);
59 VMap[I] = GV;
60 }
61
62 // Loop over the functions in the module, making external functions as before
63 for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I) {
64 Function *NF =
65 Function::Create(cast<FunctionType>(I->getType()->getElementType()),
66 I->getLinkage(), I->getName(), New);
67 NF->copyAttributesFrom(I);
68 VMap[I] = NF;
69 }
70
71 // Loop over the aliases in the module
72 for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end();
73 I != E; ++I) {
74 GlobalAlias *GA = new GlobalAlias(I->getType(), I->getLinkage(),
75 I->getName(), NULL, New);
76 GA->copyAttributesFrom(I);
77 VMap[I] = GA;
78 }
79
80 // Now that all of the things that global variable initializer can refer to
81 // have been created, loop through and copy the global variable referrers
82 // over... We also set the attributes on the global now.
83 //
84 for (Module::const_global_iterator I = M->global_begin(), E = M->global_end();
85 I != E; ++I) {
86 GlobalVariable *GV = cast<GlobalVariable>(VMap[I]);
87 if (I->hasInitializer())
88 GV->setInitializer(MapValue(I->getInitializer(), VMap));
89 }
90
91 // Similarly, copy over function bodies now...
92 //
93 for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I) {
94 Function *F = cast<Function>(VMap[I]);
95 if (!I->isDeclaration()) {
96 Function::arg_iterator DestI = F->arg_begin();
97 for (Function::const_arg_iterator J = I->arg_begin(); J != I->arg_end();
98 ++J) {
99 DestI->setName(J->getName());
100 VMap[J] = DestI++;
101 }
102
103 SmallVector<ReturnInst*, 8> Returns; // Ignore returns cloned.
104 CloneFunctionInto(F, I, VMap, /*ModuleLevelChanges=*/true, Returns);
105 }
106 }
107
108 // And aliases
109 for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end();
110 I != E; ++I) {
111 GlobalAlias *GA = cast<GlobalAlias>(VMap[I]);
112 if (const Constant *C = I->getAliasee())
113 GA->setAliasee(MapValue(C, VMap));
114 }
115
116 // And named metadata....
117 for (Module::const_named_metadata_iterator I = M->named_metadata_begin(),
118 E = M->named_metadata_end(); I != E; ++I) {
119 const NamedMDNode &NMD = *I;
120 NamedMDNode *NewNMD = New->getOrInsertNamedMetadata(NMD.getName());
121 for (unsigned i = 0, e = NMD.getNumOperands(); i != e; ++i)
122 NewNMD->addOperand(MapValue(NMD.getOperand(i), VMap));
123 }
124
125 return New;
126 }
127