diff --git a/compiler/compiler_backend.cc b/compiler/compiler_backend.cc
new file mode 100644
index 0000000..b8f21a9
--- /dev/null
+++ b/compiler/compiler_backend.cc
@@ -0,0 +1,293 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "compiler_backend.h"
+#include "elf_writer_quick.h"
+#include "dex/quick/mir_to_lir.h"
+#include "dex/mir_graph.h"
+#include "driver/compiler_driver.h"
+#include "mirror/art_method-inl.h"
+
+#ifdef ART_USE_PORTABLE_COMPILER
+#include "dex/portable/mir_to_gbc.h"
+#include "elf_writer_mclinker.h"
+#endif
+
+namespace art {
+
+#ifdef ART_SEA_IR_MODE
+extern "C" art::CompiledMethod* SeaIrCompileMethod(art::CompilerDriver& compiler,
+                                                   const art::DexFile::CodeItem* code_item,
+                                                   uint32_t access_flags,
+                                                   art::InvokeType invoke_type,
+                                                   uint16_t class_def_idx,
+                                                   uint32_t method_idx,
+                                                   jobject class_loader,
+                                                   const art::DexFile& dex_file);
+#endif
+
+extern "C" void ArtInitQuickCompilerContext(art::CompilerDriver& driver);
+extern "C" void ArtUnInitQuickCompilerContext(art::CompilerDriver& driver);
+extern "C" art::CompiledMethod* ArtQuickCompileMethod(art::CompilerDriver& compiler,
+                                                      const art::DexFile::CodeItem* code_item,
+                                                      uint32_t access_flags,
+                                                      art::InvokeType invoke_type,
+                                                      uint16_t class_def_idx,
+                                                      uint32_t method_idx,
+                                                      jobject class_loader,
+                                                      const art::DexFile& dex_file);
+
+extern "C" art::CompiledMethod* ArtQuickJniCompileMethod(art::CompilerDriver& compiler,
+                                                         uint32_t access_flags, uint32_t method_idx,
+                                                         const art::DexFile& dex_file);
+
+
+static CompiledMethod* TryCompileWithSeaIR(art::CompilerDriver& compiler,
+                                           const art::DexFile::CodeItem* code_item,
+                                           uint32_t access_flags,
+                                           art::InvokeType invoke_type,
+                                           uint16_t class_def_idx,
+                                           uint32_t method_idx,
+                                           jobject class_loader,
+                                           const art::DexFile& dex_file) {
+#ifdef ART_SEA_IR_MODE
+    bool use_sea = Runtime::Current()->IsSeaIRMode();
+    use_sea = use_sea &&
+        (std::string::npos != PrettyMethod(method_idx, dex_file).find("fibonacci"));
+    if (use_sea) {
+      LOG(INFO) << "Using SEA IR to compile..." << std::endl;
+      return SeaIrCompileMethod(compiler,
+                                code_item,
+                                access_flags,
+                                invoke_type,
+                                class_def_idx,
+                                method_idx,
+                                class_loader,
+                                dex_file);
+  }
+#endif
+  return nullptr;
+}
+
+
+class QuickBackend : public CompilerBackend {
+ public:
+  QuickBackend() : CompilerBackend(100) {}
+
+  void Init(CompilerDriver& driver) const {
+    ArtInitQuickCompilerContext(driver);
+  }
+
+  void UnInit(CompilerDriver& driver) const {
+    ArtUnInitQuickCompilerContext(driver);
+  }
+
+  CompiledMethod* Compile(CompilerDriver& compiler,
+                          const DexFile::CodeItem* code_item,
+                          uint32_t access_flags,
+                          InvokeType invoke_type,
+                          uint16_t class_def_idx,
+                          uint32_t method_idx,
+                          jobject class_loader,
+                          const DexFile& dex_file) const {
+    CompiledMethod* method = TryCompileWithSeaIR(compiler,
+                                                 code_item,
+                                                 access_flags,
+                                                 invoke_type,
+                                                 class_def_idx,
+                                                 method_idx,
+                                                 class_loader,
+                                                 dex_file);
+    if (method != nullptr) return method;
+
+    return ArtQuickCompileMethod(compiler,
+                                 code_item,
+                                 access_flags,
+                                 invoke_type,
+                                 class_def_idx,
+                                 method_idx,
+                                 class_loader,
+                                 dex_file);
+  }
+
+  CompiledMethod* JniCompile(CompilerDriver& driver,
+                             uint32_t access_flags,
+                             uint32_t method_idx,
+                             const DexFile& dex_file) const {
+    return ArtQuickJniCompileMethod(driver, access_flags, method_idx, dex_file);
+  }
+
+  uintptr_t GetEntryPointOf(mirror::ArtMethod* method) const {
+    return reinterpret_cast<uintptr_t>(method->GetEntryPointFromQuickCompiledCode());
+  }
+
+  bool WriteElf(art::File* file,
+                OatWriter& oat_writer,
+                const std::vector<const art::DexFile*>& dex_files,
+                const std::string& android_root,
+                bool is_host, const CompilerDriver& driver) const
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
+    return art::ElfWriterQuick::Create(file, oat_writer, dex_files, android_root, is_host, driver);
+  }
+
+  Backend* GetCodeGenerator(CompilationUnit* cu, void* compilation_unit) const {
+    Mir2Lir* mir_to_lir = nullptr;
+    switch (cu->instruction_set) {
+      case kThumb2:
+        mir_to_lir = ArmCodeGenerator(cu, cu->mir_graph.get(), &cu->arena);
+        break;
+      case kMips:
+        mir_to_lir = MipsCodeGenerator(cu, cu->mir_graph.get(), &cu->arena);
+        break;
+      case kX86:
+        mir_to_lir = X86CodeGenerator(cu, cu->mir_graph.get(), &cu->arena);
+        break;
+      default:
+        LOG(FATAL) << "Unexpected instruction set: " << cu->instruction_set;
+    }
+
+    /* The number of compiler temporaries depends on backend so set it up now if possible */
+    if (mir_to_lir) {
+      size_t max_temps = mir_to_lir->GetMaxPossibleCompilerTemps();
+      bool set_max = cu->mir_graph->SetMaxAvailableNonSpecialCompilerTemps(max_temps);
+      CHECK(set_max);
+    }
+    return mir_to_lir;;
+  }
+
+  void InitCompilationUnit(CompilationUnit& cu) const {}
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(QuickBackend);
+};
+
+#ifdef ART_USE_PORTABLE_COMPILER
+
+extern "C" void ArtInitCompilerContext(art::CompilerDriver& driver);
+extern "C" void ArtUnInitCompilerContext(art::CompilerDriver& driver);
+extern "C" art::CompiledMethod* ArtCompileMethod(art::CompilerDriver& driver,
+                                                 const art::DexFile::CodeItem* code_item,
+                                                 uint32_t access_flags,
+                                                 art::InvokeType invoke_type,
+                                                 uint16_t class_def_idx,
+                                                 uint32_t method_idx,
+                                                 jobject class_loader,
+                                                 const art::DexFile& dex_file);
+extern "C" art::CompiledMethod* ArtLLVMJniCompileMethod(art::CompilerDriver& driver,
+                                                        uint32_t access_flags, uint32_t method_idx,
+                                                        const art::DexFile& dex_file);
+
+
+class LLVMBackend : public CompilerBackend {
+ public:
+  LLVMBackend() : CompilerBackend(1000) {}
+
+  void Init(CompilerDriver& driver) const {
+    ArtInitCompilerContext(driver);
+  }
+
+  void UnInit(CompilerDriver& driver) const {
+    ArtUnInitCompilerContext(driver);
+  }
+
+  CompiledMethod* Compile(CompilerDriver& compiler,
+                          const DexFile::CodeItem* code_item,
+                          uint32_t access_flags,
+                          InvokeType invoke_type,
+                          uint16_t class_def_idx,
+                          uint32_t method_idx,
+                          jobject class_loader,
+                          const DexFile& dex_file) const {
+    CompiledMethod* method = TryCompileWithSeaIR(compiler,
+                                                 code_item,
+                                                 access_flags,
+                                                 invoke_type,
+                                                 class_def_idx,
+                                                 method_idx,
+                                                 class_loader,
+                                                 dex_file);
+    if (method != nullptr) return method;
+
+    return ArtCompileMethod(compiler,
+                            code_item,
+                            access_flags,
+                            invoke_type,
+                            class_def_idx,
+                            method_idx,
+                            class_loader,
+                            dex_file);
+  }
+
+  CompiledMethod* JniCompile(CompilerDriver& driver,
+                             uint32_t access_flags,
+                             uint32_t method_idx,
+                             const DexFile& dex_file) const {
+    return ArtLLVMJniCompileMethod(driver, access_flags, method_idx, dex_file);
+  }
+
+  uintptr_t GetEntryPointOf(mirror::ArtMethod* method) const {
+    return reinterpret_cast<uintptr_t>(method->GetEntryPointFromPortableCompiledCode());
+  }
+
+  bool WriteElf(art::File* file,
+                OatWriter& oat_writer,
+                const std::vector<const art::DexFile*>& dex_files,
+                const std::string& android_root,
+                bool is_host, const CompilerDriver& driver) const
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
+    return art::ElfWriterMclinker::Create(
+        file, oat_writer, dex_files, android_root, is_host, driver);
+  }
+
+  Backend* GetCodeGenerator(CompilationUnit* cu, void* compilation_unit) const {
+    return PortableCodeGenerator(
+        cu, cu->mir_graph.get(), &cu->arena,
+        reinterpret_cast<art::llvm::LlvmCompilationUnit*>(compilation_unit));
+  }
+
+  void InitCompilationUnit(CompilationUnit& cu) const {
+      // Fused long branches not currently useful in bitcode.
+    cu.disable_opt |=
+        (1 << kBranchFusing) |
+        (1 << kSuppressExceptionEdges);
+  }
+
+  bool isPortable() const { return true; }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(LLVMBackend);
+};
+#endif
+
+CompilerBackend* CompilerBackend::Create(CompilerBackend::Kind kind) {
+  switch (kind) {
+    case kQuick:
+      return new QuickBackend();
+      break;
+    case kPortable:
+#ifdef ART_USE_PORTABLE_COMPILER
+      return new LLVMBackend();
+#else
+      LOG(FATAL) << "Portable compiler not compiled";
+#endif
+      break;
+    default:
+      LOG(FATAL) << "UNREACHABLE";
+  }
+  return nullptr;
+}
+
+}  // namespace art