Initial checkin of Module cloning support stuff
llvm-svn: 4788
diff --git a/llvm/lib/Transforms/Utils/CloneModule.cpp b/llvm/lib/Transforms/Utils/CloneModule.cpp
new file mode 100644
index 0000000..043e06d
--- /dev/null
+++ b/llvm/lib/Transforms/Utils/CloneModule.cpp
@@ -0,0 +1,73 @@
+//===- CloneModule.cpp - Clone an entire module ---------------------------===//
+//
+// This file implements the CloneModule interface which makes a copy of an
+// entire module.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Transforms/Utils/Cloning.h"
+#include "llvm/Module.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/Constant.h"
+#include "ValueMapper.h"
+
+/// 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 (intializers and references,
+/// respectively) refer to the right globals.
+///
+Module *CloneModule(const Module *M) {
+ // First off, we need to create the new module...
+ Module *New = new Module();
+
+ // Create the value map that maps things from the old module over to the new
+ // module.
+ std::map<const Value*, Value*> ValueMap;
+
+ // Loop over all of the global variables, making corresponding globals in the
+ // new module. Here we add them to the ValueMap and to the new Module. We
+ // don't worry about attributes or initializers, they will come later.
+ //
+ for (Module::const_giterator I = M->gbegin(), E = M->gend(); I != E; ++I)
+ ValueMap[I] = new GlobalVariable(I->getType()->getElementType(),
+ false, false, 0, I->getName(), New);
+
+ // 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)
+ ValueMap[I]=new Function(cast<FunctionType>(I->getType()->getElementType()),
+ false, I->getName(), New);
+
+ // 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_giterator I = M->gbegin(), E = M->gend(); I != E; ++I) {
+ GlobalVariable *GV = cast<GlobalVariable>(ValueMap[I]);
+ if (I->hasInitializer())
+ GV->setInitializer(cast<Constant>(MapValue(I->getInitializer(),
+ ValueMap)));
+ if (I->hasInternalLinkage())
+ GV->setInternalLinkage(true);
+ }
+
+ // Similarly, copy over function bodies now...
+ //
+ for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I) {
+ Function *F = cast<Function>(ValueMap[I]);
+ if (!I->isExternal()) {
+ Function::aiterator DestI = F->abegin();
+ for (Function::const_aiterator J = I->abegin(); J != I->aend(); ++J) {
+ DestI->setName(J->getName());
+ ValueMap[J] = DestI++;
+ }
+
+ std::vector<ReturnInst*> Returns; // Ignore returns cloned...
+ CloneFunctionInto(F, I, ValueMap, Returns);
+ }
+
+ if (I->hasInternalLinkage())
+ F->setInternalLinkage(true);
+ }
+
+ return New;
+}