1 /* 2 * Copyright (c) 2001, 2004, 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 25 package sun.jvm.hotspot.interpreter; 26 27 import sun.jvm.hotspot.oops.*; 28 import sun.jvm.hotspot.utilities.*; 29 import sun.jvm.hotspot.runtime.VM; 30 31 public class Bytecode { 32 Method method; 33 int bci; 34 static final int jintSize = 4; 35 static final String spaces = " "; 36 static final String comma = ", "; 37 38 Bytecode(Method method, int bci) { 39 this.method = method; 40 this.bci = bci; 41 } 42 43 // Address computation 44 // NOTE: assumes that the start of the method's bytecodes is 4-byte aligned 45 int alignedOffset(int offset) { 46 return Bits.roundTo(bci + offset, jintSize) - bci; 47 } 48 49 public int getIndexU1() { return method.getBytecodeOrBPAt(bci() + 1) & 0xFF; } 50 public int getIndexU2(int bc, boolean isWide) { 51 if (can_use_native_byte_order(bc, isWide)) { 52 return method.getNativeShortArg(bci() + (isWide ? 2 : 1)) & 0xFFFF; 53 } 54 return method.getBytecodeShortArg(bci() + (isWide ? 2 : 1)) & 0xFFFF; 55 } 56 public int getIndexU4() { return method.getNativeIntArg(bci() + 1); } 57 public boolean hasIndexU4() { return code() == Bytecodes._invokedynamic; } 58 59 public int getIndexU1Cpcache() { return method.getBytecodeOrBPAt(bci() + 1) & 0xFF; } 60 public int getIndexU2Cpcache() { return method.getNativeShortArg(bci() + 1) & 0xFFFF; } 61 62 static boolean can_use_native_byte_order(int bc, boolean is_wide) { 63 return (VM.getVM().isBigEndian() || Bytecodes.native_byte_order(bc /*, is_wide*/)); 64 } 65 66 int javaSignedWordAt(int offset) { 67 return method.getBytecodeIntArg(bci + offset); 68 } 69 70 short javaShortAt(int offset) { 71 return method.getBytecodeShortArg(bci + offset); 72 } 73 74 byte javaByteAt(int offset) { 75 return method.getBytecodeByteArg(bci + offset); 76 } 77 78 public Method method() { return method; } 79 public int bci() { return bci; } 80 81 // hotspot byte code 82 public int code() { 83 return Bytecodes.codeAt(method(), bci()); 84 } 85 86 // jvm byte code 87 public int javaCode() { 88 return Bytecodes.javaCode(code()); 89 } 90 91 public String getBytecodeName() { 92 return Bytecodes.name(code()); 93 } 94 95 public String getJavaBytecodeName() { 96 return Bytecodes.name(javaCode()); 97 } 98 99 public int getLength() { 100 return Bytecodes.lengthAt(method(), bci()); 101 } 102 103 public int getJavaLength() { 104 return Bytecodes.javaLengthAt(method(), bci()); 105 } 106 107 public String toString() { 108 StringBuffer buf = new StringBuffer(getJavaBytecodeName()); 109 if (code() != javaCode()) { 110 buf.append(spaces); 111 buf.append('['); 112 buf.append(getBytecodeName()); 113 buf.append(']'); 114 } 115 return buf.toString(); 116 } 117 }