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diff --git a/lib/Transforms/Utils/CloneFunction.cpp b/lib/Transforms/Utils/CloneFunction.cpp
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+++ b/lib/Transforms/Utils/CloneFunction.cpp
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+//===- CloneFunction.cpp - Clone a function into another function ---------===//
+//
+//                     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 CloneFunctionInto interface, which is used as the
+// low-level function cloner.  This is used by the CloneFunction and function
+// inliner to do the dirty work of copying the body of a function around.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Transforms/Utils/Cloning.h"
+#include "llvm/Instructions.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/Function.h"
+#include "ValueMapper.h"
+using namespace llvm;
+
+// CloneBasicBlock - See comments in Cloning.h
+BasicBlock *llvm::CloneBasicBlock(const BasicBlock *BB,
+                                  std::map<const Value*, Value*> &ValueMap,
+                                  const char *NameSuffix, Function *F) {
+  BasicBlock *NewBB = new BasicBlock("", F);
+  if (BB->hasName()) NewBB->setName(BB->getName()+NameSuffix);
+
+  // Loop over all instructions copying them over...
+  for (BasicBlock::const_iterator II = BB->begin(), IE = BB->end();
+       II != IE; ++II) {
+    Instruction *NewInst = II->clone();
+    if (II->hasName())
+      NewInst->setName(II->getName()+NameSuffix);
+    NewBB->getInstList().push_back(NewInst);
+    ValueMap[II] = NewInst;                // Add instruction map to value.
+  }
+  return NewBB;
+}
+
+// Clone OldFunc into NewFunc, transforming the old arguments into references to
+// ArgMap values.
+//
+void llvm::CloneFunctionInto(Function *NewFunc, const Function *OldFunc,
+                             std::map<const Value*, Value*> &ValueMap,
+                             std::vector<ReturnInst*> &Returns,
+                             const char *NameSuffix) {
+  assert(NameSuffix && "NameSuffix cannot be null!");
+
+#ifndef NDEBUG
+  for (Function::const_arg_iterator I = OldFunc->arg_begin(), E = OldFunc->arg_end();
+       I != E; ++I)
+    assert(ValueMap.count(I) && "No mapping from source argument specified!");
+#endif
+
+  // Loop over all of the basic blocks in the function, cloning them as
+  // appropriate.  Note that we save BE this way in order to handle cloning of
+  // recursive functions into themselves.
+  //
+  for (Function::const_iterator BI = OldFunc->begin(), BE = OldFunc->end();
+       BI != BE; ++BI) {
+    const BasicBlock &BB = *BI;
+
+    // Create a new basic block and copy instructions into it!
+    BasicBlock *CBB = CloneBasicBlock(&BB, ValueMap, NameSuffix, NewFunc);
+    ValueMap[&BB] = CBB;                       // Add basic block mapping.
+
+    if (ReturnInst *RI = dyn_cast<ReturnInst>(CBB->getTerminator()))
+      Returns.push_back(RI);
+  }
+
+  // Loop over all of the instructions in the function, fixing up operand
+  // references as we go.  This uses ValueMap to do all the hard work.
+  //
+  for (Function::iterator BB = cast<BasicBlock>(ValueMap[OldFunc->begin()]),
+         BE = NewFunc->end(); BB != BE; ++BB)
+    // Loop over all instructions, fixing each one as we find it...
+    for (BasicBlock::iterator II = BB->begin(); II != BB->end(); ++II)
+      RemapInstruction(II, ValueMap);
+}
+
+/// CloneFunction - Return a copy of the specified function, but without
+/// embedding the function into another module.  Also, any references specified
+/// in the ValueMap are changed to refer to their mapped value instead of the
+/// original one.  If any of the arguments to the function are in the ValueMap,
+/// the arguments are deleted from the resultant function.  The ValueMap is
+/// updated to include mappings from all of the instructions and basicblocks in
+/// the function from their old to new values.
+///
+Function *llvm::CloneFunction(const Function *F,
+                              std::map<const Value*, Value*> &ValueMap) {
+  std::vector<const Type*> ArgTypes;
+
+  // The user might be deleting arguments to the function by specifying them in
+  // the ValueMap.  If so, we need to not add the arguments to the arg ty vector
+  //
+  for (Function::const_arg_iterator I = F->arg_begin(), E = F->arg_end(); I != E; ++I)
+    if (ValueMap.count(I) == 0)  // Haven't mapped the argument to anything yet?
+      ArgTypes.push_back(I->getType());
+
+  // Create a new function type...
+  FunctionType *FTy = FunctionType::get(F->getFunctionType()->getReturnType(),
+                                    ArgTypes, F->getFunctionType()->isVarArg());
+
+  // Create the new function...
+  Function *NewF = new Function(FTy, F->getLinkage(), F->getName());
+
+  // Loop over the arguments, copying the names of the mapped arguments over...
+  Function::arg_iterator DestI = NewF->arg_begin();
+  for (Function::const_arg_iterator I = F->arg_begin(), E = F->arg_end(); I != E; ++I)
+    if (ValueMap.count(I) == 0) {   // Is this argument preserved?
+      DestI->setName(I->getName()); // Copy the name over...
+      ValueMap[I] = DestI++;        // Add mapping to ValueMap
+    }
+
+  std::vector<ReturnInst*> Returns;  // Ignore returns cloned...
+  CloneFunctionInto(NewF, F, ValueMap, Returns);
+  return NewF;
+}
+