1 /*
2 * Copyright (C) 2015 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include "jni.h"
18
19 #include <iostream>
20
21 #include "art_method.h"
22 #include "jit/jit.h"
23 #include "linear_alloc.h"
24 #include "nativehelper/ScopedUtfChars.h"
25 #include "runtime.h"
26 #include "scoped_thread_state_change-inl.h"
27 #include "thread-current-inl.h"
28
29 namespace art {
30 namespace {
31
Java_Main_getArtMethod(JNIEnv * env,jclass,jobject java_method)32 extern "C" JNIEXPORT jlong JNICALL Java_Main_getArtMethod(JNIEnv* env,
33 jclass,
34 jobject java_method) {
35 ScopedObjectAccess soa(env);
36 ArtMethod* method = ArtMethod::FromReflectedMethod(soa, java_method);
37 return static_cast<jlong>(reinterpret_cast<uintptr_t>(method));
38 }
39
Java_Main_reuseArenaOfMethod(JNIEnv *,jclass,jlong art_method)40 extern "C" JNIEXPORT void JNICALL Java_Main_reuseArenaOfMethod(JNIEnv*,
41 jclass,
42 jlong art_method) {
43 // Create a new allocation and use it to request a specified amount of arenas.
44 // Hopefully one of them is a reused one, the one that covers the art_method pointer.
45 std::unique_ptr<LinearAlloc> alloc(Runtime::Current()->CreateLinearAlloc());
46 do {
47 // Ask for a byte - it's sufficient to get an arena and not have issues with size.
48 alloc->Alloc(Thread::Current(), 1);
49 } while (!alloc->Contains(reinterpret_cast<void*>(static_cast<uintptr_t>(art_method))));
50 }
51
52 } // namespace
53 } // namespace art
54