| /* |
| * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| import java.lang.reflect.Field; |
| import java.lang.reflect.Method; |
| import java.util.List; |
| import java.util.Set; |
| import java.util.stream.Collectors; |
| import java.lang.StackWalker.StackFrame; |
| |
| public class LocalLongHelper { |
| static StackWalker sw; |
| static Method longValue; |
| static Method getLocals; |
| static Class<?> primitiveValueClass; |
| static Method primitiveSize; |
| static Method getMethodType; |
| static Field memberName; |
| static Field offset; |
| |
| public static void main(String[] args) throws Throwable { |
| setupReflectionStatics(); |
| new LocalLongHelper().longArg(0xC0FFEE, 0x1234567890ABCDEFL); |
| } |
| |
| // locals[2] contains the unused slot of the long argument. |
| public long longArg(int i, long l) throws Throwable { |
| List<StackFrame> frames = sw.walk(s -> s.collect(Collectors.toList())); |
| Object[] locals = (Object[]) getLocals.invoke(frames.get(0)); |
| |
| if (8 == (int) primitiveSize.invoke(locals[2])) { // Only test 64-bit |
| long locals_2 = (long) longValue.invoke(locals[2]); |
| if (locals_2 != 0){ |
| throw new RuntimeException("Expected locals_2 == 0"); |
| } |
| } |
| return l; // Don't want l to become a dead var |
| } |
| |
| private static void setupReflectionStatics() throws Throwable { |
| Class<?> liveStackFrameClass = Class.forName("java.lang.LiveStackFrame"); |
| primitiveValueClass = Class.forName("java.lang.LiveStackFrame$PrimitiveSlot"); |
| |
| getLocals = liveStackFrameClass.getDeclaredMethod("getLocals"); |
| getLocals.setAccessible(true); |
| |
| longValue = primitiveValueClass.getDeclaredMethod("longValue"); |
| longValue.setAccessible(true); |
| |
| Class<?> stackFrameInfoClass = Class.forName("java.lang.StackFrameInfo"); |
| memberName = stackFrameInfoClass.getDeclaredField("memberName"); |
| memberName.setAccessible(true); |
| offset = stackFrameInfoClass.getDeclaredField("bci"); |
| offset.setAccessible(true); |
| getMethodType = Class.forName("java.lang.invoke.MemberName").getDeclaredMethod("getMethodType"); |
| getMethodType.setAccessible(true); |
| |
| Class<?> extendedOptionClass = Class.forName("java.lang.StackWalker$ExtendedOption"); |
| Method ewsNI = StackWalker.class.getDeclaredMethod("newInstance", Set.class, extendedOptionClass); |
| ewsNI.setAccessible(true); |
| Field f = extendedOptionClass.getDeclaredField("LOCALS_AND_OPERANDS"); |
| f.setAccessible(true); |
| Object localsAndOperandsOption = f.get(null); |
| |
| primitiveSize = primitiveValueClass.getDeclaredMethod("size"); |
| primitiveSize.setAccessible(true); |
| sw = (StackWalker) ewsNI.invoke(null, java.util.Collections.emptySet(), localsAndOperandsOption); |
| } |
| } |