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diff --git a/include/llvm/IR/PassManager.h b/include/llvm/IR/PassManager.h
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+//===- PassManager.h - LegacyContainer for Passes --------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+/// \file
+///
+/// This header defines various interfaces for pass management in LLVM. There
+/// is no "pass" interface in LLVM per se. Instead, an instance of any class
+/// which supports a method to 'run' it over a unit of IR can be used as
+/// a pass. A pass manager is generally a tool to collect a sequence of passes
+/// which run over a particular IR construct, and run each of them in sequence
+/// over each such construct in the containing IR construct. As there is no
+/// containing IR construct for a Module, a manager for passes over modules
+/// forms the base case which runs its managed passes in sequence over the
+/// single module provided.
+///
+/// The core IR library provides managers for running passes over
+/// modules and functions.
+///
+/// * FunctionPassManager can run over a Module, runs each pass over
+///   a Function.
+/// * ModulePassManager must be directly run, runs each pass over the Module.
+///
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/polymorphic_ptr.h"
+#include "llvm/IR/Module.h"
+#include <vector>
+
+namespace llvm {
+
+class Module;
+class Function;
+
+/// \brief Implementation details of the pass manager interfaces.
+namespace detail {
+
+/// \brief Template for the abstract base class used to dispatch
+/// polymorphically over pass objects.
+template <typename T> struct PassConcept {
+  // Boiler plate necessary for the container of derived classes.
+  virtual ~PassConcept() {}
+  virtual PassConcept *clone() = 0;
+
+  /// \brief The polymorphic API which runs the pass over a given IR entity.
+  virtual bool run(T Arg) = 0;
+};
+
+/// \brief A template wrapper used to implement the polymorphic API.
+///
+/// Can be instantiated for any object which provides a \c run method
+/// accepting a \c T. It requires the pass to be a copyable
+/// object.
+template <typename T, typename PassT> struct PassModel : PassConcept<T> {
+  PassModel(PassT Pass) : Pass(llvm_move(Pass)) {}
+  virtual PassModel *clone() { return new PassModel(Pass); }
+  virtual bool run(T Arg) { return Pass.run(Arg); }
+  PassT Pass;
+};
+
+}
+
+class ModulePassManager {
+public:
+  ModulePassManager(Module *M) : M(M) {}
+
+  template <typename ModulePassT> void addPass(ModulePassT Pass) {
+    Passes.push_back(new ModulePassModel<ModulePassT>(llvm_move(Pass)));
+  }
+
+  void run() {
+    for (unsigned Idx = 0, Size = Passes.size(); Idx != Size; ++Idx)
+      Passes[Idx]->run(M);
+  }
+
+private:
+  // Pull in the concept type and model template specialized for modules.
+  typedef detail::PassConcept<Module *> ModulePassConcept;
+  template <typename PassT>
+  struct ModulePassModel : detail::PassModel<Module *, PassT> {
+    ModulePassModel(PassT Pass) : detail::PassModel<Module *, PassT>(Pass) {}
+  };
+
+  Module *M;
+  std::vector<polymorphic_ptr<ModulePassConcept> > Passes;
+};
+
+class FunctionPassManager {
+public:
+  template <typename FunctionPassT> void addPass(FunctionPassT Pass) {
+    Passes.push_back(new FunctionPassModel<FunctionPassT>(llvm_move(Pass)));
+  }
+
+  bool run(Module *M) {
+    bool Changed = false;
+    for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I)
+      for (unsigned Idx = 0, Size = Passes.size(); Idx != Size; ++Idx)
+        Changed |= Passes[Idx]->run(I);
+    return Changed;
+  }
+
+private:
+  // Pull in the concept type and model template specialized for functions.
+  typedef detail::PassConcept<Function *> FunctionPassConcept;
+  template <typename PassT>
+  struct FunctionPassModel : detail::PassModel<Function *, PassT> {
+    FunctionPassModel(PassT Pass)
+        : detail::PassModel<Function *, PassT>(Pass) {}
+  };
+
+  std::vector<polymorphic_ptr<FunctionPassConcept> > Passes;
+};
+
+}