Add an abstraction over a compiled code.

That's just step 1, moving code-related functions of ArtMethod to
another class. That class is only a wrapper on an ArtMethod, but will
be changed to be a wrapper around compiled code.

Change-Id: I6f35fc06d37220558dff61691e51ae20066b0dd6
diff --git a/runtime/art_code.h b/runtime/art_code.h
new file mode 100644
index 0000000..1d2d898
--- /dev/null
+++ b/runtime/art_code.h
@@ -0,0 +1,93 @@
+/*
+ * Copyright (C) 2015 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.
+ */
+
+#ifndef ART_RUNTIME_ART_CODE_H_
+#define ART_RUNTIME_ART_CODE_H_
+
+#include "base/mutex.h"
+#include "offsets.h"
+#include "quick/quick_method_frame_info.h"
+#include "stack_map.h"
+
+namespace art {
+
+class ArtMethod;
+
+class ArtCode FINAL {
+ public:
+  explicit ArtCode(ArtMethod** method) : method_(*method) {}
+  explicit ArtCode(ArtMethod* method) : method_(method) {}
+  ArtCode() : method_(nullptr) {}
+
+  // Converts a dex PC to a native PC.
+  uintptr_t ToNativeQuickPc(const uint32_t dex_pc,
+                            bool is_for_catch_handler,
+                            bool abort_on_failure = true)
+      SHARED_REQUIRES(Locks::mutator_lock_);
+
+  bool IsOptimized(size_t pointer_size) SHARED_REQUIRES(Locks::mutator_lock_);
+
+  CodeInfo GetOptimizedCodeInfo() SHARED_REQUIRES(Locks::mutator_lock_);
+
+  uintptr_t NativeQuickPcOffset(const uintptr_t pc) SHARED_REQUIRES(Locks::mutator_lock_);
+
+  // Converts a native PC to a dex PC.
+  uint32_t ToDexPc(const uintptr_t pc, bool abort_on_failure = true)
+      SHARED_REQUIRES(Locks::mutator_lock_);
+
+  // Callers should wrap the uint8_t* in a GcMap instance for convenient access.
+  const uint8_t* GetNativeGcMap(size_t pointer_size) SHARED_REQUIRES(Locks::mutator_lock_);
+
+  const uint8_t* GetVmapTable(size_t pointer_size) SHARED_REQUIRES(Locks::mutator_lock_);
+
+  const uint8_t* GetMappingTable(size_t pointer_size) SHARED_REQUIRES(Locks::mutator_lock_);
+
+  QuickMethodFrameInfo GetQuickFrameInfo() SHARED_REQUIRES(Locks::mutator_lock_);
+
+  FrameOffset GetReturnPcOffset() SHARED_REQUIRES(Locks::mutator_lock_) {
+    return FrameOffset(GetFrameSizeInBytes() - sizeof(void*));
+  }
+
+  template <bool kCheckFrameSize = true>
+  uint32_t GetFrameSizeInBytes() SHARED_REQUIRES(Locks::mutator_lock_) {
+    uint32_t result = GetQuickFrameInfo().FrameSizeInBytes();
+    if (kCheckFrameSize) {
+      DCHECK_LE(static_cast<size_t>(kStackAlignment), result);
+    }
+    return result;
+  }
+
+  const void* GetQuickOatEntryPoint(size_t pointer_size) SHARED_REQUIRES(Locks::mutator_lock_);
+
+  void AssertPcIsWithinQuickCode(uintptr_t pc) SHARED_REQUIRES(Locks::mutator_lock_);
+
+  bool PcIsWithinQuickCode(uintptr_t pc) SHARED_REQUIRES(Locks::mutator_lock_);
+
+  FrameOffset GetHandleScopeOffset() SHARED_REQUIRES(Locks::mutator_lock_) {
+    constexpr size_t handle_scope_offset = sizeof(ArtMethod*);
+    DCHECK_LT(handle_scope_offset, GetFrameSizeInBytes());
+    return FrameOffset(handle_scope_offset);
+  }
+
+  ArtMethod* GetMethod() const { return method_; }
+
+ private:
+  ArtMethod* method_;
+};
+
+}  // namespace art
+
+#endif  // ART_RUNTIME_ART_CODE_H_