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 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 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
