BytecodeGotoW.java revision 9883:903a2e023ffb
1/* 2 * Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25package sun.jvm.hotspot.interpreter; 26 27import sun.jvm.hotspot.oops.*; 28import sun.jvm.hotspot.utilities.*; 29 30public class BytecodeGotoW extends BytecodeJmp { 31 BytecodeGotoW(Method method, int bci) { 32 super(method, bci); 33 } 34 35 public int getTargetBCI() { 36 return bci() + javaSignedWordAt(1); 37 } 38 39 public void verify() { 40 if (Assert.ASSERTS_ENABLED) { 41 Assert.that(isValid(), "check goto_w"); 42 } 43 } 44 45 public boolean isValid() { 46 return javaCode() == Bytecodes._goto_w; 47 } 48 49 public static BytecodeGotoW at(Method method, int bci) { 50 BytecodeGotoW b = new BytecodeGotoW(method, bci); 51 if (Assert.ASSERTS_ENABLED) { 52 b.verify(); 53 } 54 return b; 55 } 56 57 /** Like at, but returns null if the BCI is not at goto_w */ 58 public static BytecodeGotoW atCheck(Method method, int bci) { 59 BytecodeGotoW b = new BytecodeGotoW(method, bci); 60 return (b.isValid() ? b : null); 61 } 62 63 public static BytecodeGotoW at(BytecodeStream bcs) { 64 return new BytecodeGotoW(bcs.method(), bcs.bci()); 65 } 66} 67