1 /*

     2  * reserved comment block

     3  * DO NOT REMOVE OR ALTER!

     4  */

     5 /*

     6  * Licensed to the Apache Software Foundation (ASF) under one or more

     7  * contributor license agreements.  See the NOTICE file distributed with

     8  * this work for additional information regarding copyright ownership.

     9  * The ASF licenses this file to You under the Apache License, Version 2.0

    10  * (the "License"); you may not use this file except in compliance with

    11  * the License.  You may obtain a copy of the License at

    12  *

    13  *      http://www.apache.org/licenses/LICENSE-2.0

    14  *

    15  * Unless required by applicable law or agreed to in writing, software

    16  * distributed under the License is distributed on an "AS IS" BASIS,

    17  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

    18  * See the License for the specific language governing permissions and

    19  * limitations under the License.

    20  */

    21 

    22 package com.sun.org.apache.bcel.internal.generic;

    23 

    24 import com.sun.org.apache.bcel.internal.Const;

    25 

    26 /**

    27  * This interface contains shareable instruction objects.

    28  *

    29  * In order to save memory you can use some instructions multiply,

    30  * since they have an immutable state and are directly derived from

    31  * Instruction.  I.e. they have no instance fields that could be

    32  * changed. Since some of these instructions like ICONST_0 occur

    33  * very frequently this can save a lot of time and space. This

    34  * feature is an adaptation of the FlyWeight design pattern, we

    35  * just use an array instead of a factory.

    36  *

    37  * The Instructions can also accessed directly under their names, so

    38  * it's possible to write il.append(Instruction.ICONST_0);

    39  *

    40  * @version $Id: InstructionConst.java 1695415 2015-08-12 01:02:39Z chas $

    41  */

    42 public final class InstructionConst {

    43 

    44     /**

    45      * Predefined instruction objects

    46      */

    47     /*

    48      * NOTE these are not currently immutable, because Instruction

    49      * has mutable protected fields opcode and length.

    50      */

    51     public static final Instruction NOP = new NOP();

    52     public static final Instruction ACONST_NULL = new ACONST_NULL();

    53     public static final Instruction ICONST_M1 = new ICONST(-1);

    54     public static final Instruction ICONST_0 = new ICONST(0);

    55     public static final Instruction ICONST_1 = new ICONST(1);

    56     public static final Instruction ICONST_2 = new ICONST(2);

    57     public static final Instruction ICONST_3 = new ICONST(3);

    58     public static final Instruction ICONST_4 = new ICONST(4);

    59     public static final Instruction ICONST_5 = new ICONST(5);

    60     public static final Instruction LCONST_0 = new LCONST(0);

    61     public static final Instruction LCONST_1 = new LCONST(1);

    62     public static final Instruction FCONST_0 = new FCONST(0);

    63     public static final Instruction FCONST_1 = new FCONST(1);

    64     public static final Instruction FCONST_2 = new FCONST(2);

    65     public static final Instruction DCONST_0 = new DCONST(0);

    66     public static final Instruction DCONST_1 = new DCONST(1);

    67     public static final ArrayInstruction IALOAD = new IALOAD();

    68     public static final ArrayInstruction LALOAD = new LALOAD();

    69     public static final ArrayInstruction FALOAD = new FALOAD();

    70     public static final ArrayInstruction DALOAD = new DALOAD();

    71     public static final ArrayInstruction AALOAD = new AALOAD();

    72     public static final ArrayInstruction BALOAD = new BALOAD();

    73     public static final ArrayInstruction CALOAD = new CALOAD();

    74     public static final ArrayInstruction SALOAD = new SALOAD();

    75     public static final ArrayInstruction IASTORE = new IASTORE();

    76     public static final ArrayInstruction LASTORE = new LASTORE();

    77     public static final ArrayInstruction FASTORE = new FASTORE();

    78     public static final ArrayInstruction DASTORE = new DASTORE();

    79     public static final ArrayInstruction AASTORE = new AASTORE();

    80     public static final ArrayInstruction BASTORE = new BASTORE();

    81     public static final ArrayInstruction CASTORE = new CASTORE();

    82     public static final ArrayInstruction SASTORE = new SASTORE();

    83     public static final StackInstruction POP = new POP();

    84     public static final StackInstruction POP2 = new POP2();

    85     public static final StackInstruction DUP = new DUP();

    86     public static final StackInstruction DUP_X1 = new DUP_X1();

    87     public static final StackInstruction DUP_X2 = new DUP_X2();

    88     public static final StackInstruction DUP2 = new DUP2();

    89     public static final StackInstruction DUP2_X1 = new DUP2_X1();

    90     public static final StackInstruction DUP2_X2 = new DUP2_X2();

    91     public static final StackInstruction SWAP = new SWAP();

    92     public static final ArithmeticInstruction IADD = new IADD();

    93     public static final ArithmeticInstruction LADD = new LADD();

    94     public static final ArithmeticInstruction FADD = new FADD();

    95     public static final ArithmeticInstruction DADD = new DADD();

    96     public static final ArithmeticInstruction ISUB = new ISUB();

    97     public static final ArithmeticInstruction LSUB = new LSUB();

    98     public static final ArithmeticInstruction FSUB = new FSUB();

    99     public static final ArithmeticInstruction DSUB = new DSUB();

   100     public static final ArithmeticInstruction IMUL = new IMUL();

   101     public static final ArithmeticInstruction LMUL = new LMUL();

   102     public static final ArithmeticInstruction FMUL = new FMUL();

   103     public static final ArithmeticInstruction DMUL = new DMUL();

   104     public static final ArithmeticInstruction IDIV = new IDIV();

   105     public static final ArithmeticInstruction LDIV = new LDIV();

   106     public static final ArithmeticInstruction FDIV = new FDIV();

   107     public static final ArithmeticInstruction DDIV = new DDIV();

   108     public static final ArithmeticInstruction IREM = new IREM();

   109     public static final ArithmeticInstruction LREM = new LREM();

   110     public static final ArithmeticInstruction FREM = new FREM();

   111     public static final ArithmeticInstruction DREM = new DREM();

   112     public static final ArithmeticInstruction INEG = new INEG();

   113     public static final ArithmeticInstruction LNEG = new LNEG();

   114     public static final ArithmeticInstruction FNEG = new FNEG();

   115     public static final ArithmeticInstruction DNEG = new DNEG();

   116     public static final ArithmeticInstruction ISHL = new ISHL();

   117     public static final ArithmeticInstruction LSHL = new LSHL();

   118     public static final ArithmeticInstruction ISHR = new ISHR();

   119     public static final ArithmeticInstruction LSHR = new LSHR();

   120     public static final ArithmeticInstruction IUSHR = new IUSHR();

   121     public static final ArithmeticInstruction LUSHR = new LUSHR();

   122     public static final ArithmeticInstruction IAND = new IAND();

   123     public static final ArithmeticInstruction LAND = new LAND();

   124     public static final ArithmeticInstruction IOR = new IOR();

   125     public static final ArithmeticInstruction LOR = new LOR();

   126     public static final ArithmeticInstruction IXOR = new IXOR();

   127     public static final ArithmeticInstruction LXOR = new LXOR();

   128     public static final ConversionInstruction I2L = new I2L();

   129     public static final ConversionInstruction I2F = new I2F();

   130     public static final ConversionInstruction I2D = new I2D();

   131     public static final ConversionInstruction L2I = new L2I();

   132     public static final ConversionInstruction L2F = new L2F();

   133     public static final ConversionInstruction L2D = new L2D();

   134     public static final ConversionInstruction F2I = new F2I();

   135     public static final ConversionInstruction F2L = new F2L();

   136     public static final ConversionInstruction F2D = new F2D();

   137     public static final ConversionInstruction D2I = new D2I();

   138     public static final ConversionInstruction D2L = new D2L();

   139     public static final ConversionInstruction D2F = new D2F();

   140     public static final ConversionInstruction I2B = new I2B();

   141     public static final ConversionInstruction I2C = new I2C();

   142     public static final ConversionInstruction I2S = new I2S();

   143     public static final Instruction LCMP = new LCMP();

   144     public static final Instruction FCMPL = new FCMPL();

   145     public static final Instruction FCMPG = new FCMPG();

   146     public static final Instruction DCMPL = new DCMPL();

   147     public static final Instruction DCMPG = new DCMPG();

   148     public static final ReturnInstruction IRETURN = new IRETURN();

   149     public static final ReturnInstruction LRETURN = new LRETURN();

   150     public static final ReturnInstruction FRETURN = new FRETURN();

   151     public static final ReturnInstruction DRETURN = new DRETURN();

   152     public static final ReturnInstruction ARETURN = new ARETURN();

   153     public static final ReturnInstruction RETURN = new RETURN();

   154     public static final Instruction ARRAYLENGTH = new ARRAYLENGTH();

   155     public static final Instruction ATHROW = new ATHROW();

   156     public static final Instruction MONITORENTER = new MONITORENTER();

   157     public static final Instruction MONITOREXIT = new MONITOREXIT();

   158 

   159     /** You can use these constants in multiple places safely, if you can guarantee

   160      * that you will never alter their internal values, e.g. call setIndex().

   161      */

   162     public static final LocalVariableInstruction THIS = new ALOAD(0);

   163     public static final LocalVariableInstruction ALOAD_0 = THIS;

   164     public static final LocalVariableInstruction ALOAD_1 = new ALOAD(1);

   165     public static final LocalVariableInstruction ALOAD_2 = new ALOAD(2);

   166     public static final LocalVariableInstruction ILOAD_0 = new ILOAD(0);

   167     public static final LocalVariableInstruction ILOAD_1 = new ILOAD(1);

   168     public static final LocalVariableInstruction ILOAD_2 = new ILOAD(2);

   169     public static final LocalVariableInstruction ASTORE_0 = new ASTORE(0);

   170     public static final LocalVariableInstruction ASTORE_1 = new ASTORE(1);

   171     public static final LocalVariableInstruction ASTORE_2 = new ASTORE(2);

   172     public static final LocalVariableInstruction ISTORE_0 = new ISTORE(0);

   173     public static final LocalVariableInstruction ISTORE_1 = new ISTORE(1);

   174     public static final LocalVariableInstruction ISTORE_2 = new ISTORE(2);

   175 

   176     /** Get object via its opcode, for immutable instructions like

   177      * branch instructions entries are set to null.

   178      */

   179     private static final Instruction[] INSTRUCTIONS = new Instruction[256];

   180 

   181     static {

   182         INSTRUCTIONS[Const.NOP] = NOP;

   183         INSTRUCTIONS[Const.ACONST_NULL] = ACONST_NULL;

   184         INSTRUCTIONS[Const.ICONST_M1] = ICONST_M1;

   185         INSTRUCTIONS[Const.ICONST_0] = ICONST_0;

   186         INSTRUCTIONS[Const.ICONST_1] = ICONST_1;

   187         INSTRUCTIONS[Const.ICONST_2] = ICONST_2;

   188         INSTRUCTIONS[Const.ICONST_3] = ICONST_3;

   189         INSTRUCTIONS[Const.ICONST_4] = ICONST_4;

   190         INSTRUCTIONS[Const.ICONST_5] = ICONST_5;

   191         INSTRUCTIONS[Const.LCONST_0] = LCONST_0;

   192         INSTRUCTIONS[Const.LCONST_1] = LCONST_1;

   193         INSTRUCTIONS[Const.FCONST_0] = FCONST_0;

   194         INSTRUCTIONS[Const.FCONST_1] = FCONST_1;

   195         INSTRUCTIONS[Const.FCONST_2] = FCONST_2;

   196         INSTRUCTIONS[Const.DCONST_0] = DCONST_0;

   197         INSTRUCTIONS[Const.DCONST_1] = DCONST_1;

   198         INSTRUCTIONS[Const.IALOAD] = IALOAD;

   199         INSTRUCTIONS[Const.LALOAD] = LALOAD;

   200         INSTRUCTIONS[Const.FALOAD] = FALOAD;

   201         INSTRUCTIONS[Const.DALOAD] = DALOAD;

   202         INSTRUCTIONS[Const.AALOAD] = AALOAD;

   203         INSTRUCTIONS[Const.BALOAD] = BALOAD;

   204         INSTRUCTIONS[Const.CALOAD] = CALOAD;

   205         INSTRUCTIONS[Const.SALOAD] = SALOAD;

   206         INSTRUCTIONS[Const.IASTORE] = IASTORE;

   207         INSTRUCTIONS[Const.LASTORE] = LASTORE;

   208         INSTRUCTIONS[Const.FASTORE] = FASTORE;

   209         INSTRUCTIONS[Const.DASTORE] = DASTORE;

   210         INSTRUCTIONS[Const.AASTORE] = AASTORE;

   211         INSTRUCTIONS[Const.BASTORE] = BASTORE;

   212         INSTRUCTIONS[Const.CASTORE] = CASTORE;

   213         INSTRUCTIONS[Const.SASTORE] = SASTORE;

   214         INSTRUCTIONS[Const.POP] = POP;

   215         INSTRUCTIONS[Const.POP2] = POP2;

   216         INSTRUCTIONS[Const.DUP] = DUP;

   217         INSTRUCTIONS[Const.DUP_X1] = DUP_X1;

   218         INSTRUCTIONS[Const.DUP_X2] = DUP_X2;

   219         INSTRUCTIONS[Const.DUP2] = DUP2;

   220         INSTRUCTIONS[Const.DUP2_X1] = DUP2_X1;

   221         INSTRUCTIONS[Const.DUP2_X2] = DUP2_X2;

   222         INSTRUCTIONS[Const.SWAP] = SWAP;

   223         INSTRUCTIONS[Const.IADD] = IADD;

   224         INSTRUCTIONS[Const.LADD] = LADD;

   225         INSTRUCTIONS[Const.FADD] = FADD;

   226         INSTRUCTIONS[Const.DADD] = DADD;

   227         INSTRUCTIONS[Const.ISUB] = ISUB;

   228         INSTRUCTIONS[Const.LSUB] = LSUB;

   229         INSTRUCTIONS[Const.FSUB] = FSUB;

   230         INSTRUCTIONS[Const.DSUB] = DSUB;

   231         INSTRUCTIONS[Const.IMUL] = IMUL;

   232         INSTRUCTIONS[Const.LMUL] = LMUL;

   233         INSTRUCTIONS[Const.FMUL] = FMUL;

   234         INSTRUCTIONS[Const.DMUL] = DMUL;

   235         INSTRUCTIONS[Const.IDIV] = IDIV;

   236         INSTRUCTIONS[Const.LDIV] = LDIV;

   237         INSTRUCTIONS[Const.FDIV] = FDIV;

   238         INSTRUCTIONS[Const.DDIV] = DDIV;

   239         INSTRUCTIONS[Const.IREM] = IREM;

   240         INSTRUCTIONS[Const.LREM] = LREM;

   241         INSTRUCTIONS[Const.FREM] = FREM;

   242         INSTRUCTIONS[Const.DREM] = DREM;

   243         INSTRUCTIONS[Const.INEG] = INEG;

   244         INSTRUCTIONS[Const.LNEG] = LNEG;

   245         INSTRUCTIONS[Const.FNEG] = FNEG;

   246         INSTRUCTIONS[Const.DNEG] = DNEG;

   247         INSTRUCTIONS[Const.ISHL] = ISHL;

   248         INSTRUCTIONS[Const.LSHL] = LSHL;

   249         INSTRUCTIONS[Const.ISHR] = ISHR;

   250         INSTRUCTIONS[Const.LSHR] = LSHR;

   251         INSTRUCTIONS[Const.IUSHR] = IUSHR;

   252         INSTRUCTIONS[Const.LUSHR] = LUSHR;

   253         INSTRUCTIONS[Const.IAND] = IAND;

   254         INSTRUCTIONS[Const.LAND] = LAND;

   255         INSTRUCTIONS[Const.IOR] = IOR;

   256         INSTRUCTIONS[Const.LOR] = LOR;

   257         INSTRUCTIONS[Const.IXOR] = IXOR;

   258         INSTRUCTIONS[Const.LXOR] = LXOR;

   259         INSTRUCTIONS[Const.I2L] = I2L;

   260         INSTRUCTIONS[Const.I2F] = I2F;

   261         INSTRUCTIONS[Const.I2D] = I2D;

   262         INSTRUCTIONS[Const.L2I] = L2I;

   263         INSTRUCTIONS[Const.L2F] = L2F;

   264         INSTRUCTIONS[Const.L2D] = L2D;

   265         INSTRUCTIONS[Const.F2I] = F2I;

   266         INSTRUCTIONS[Const.F2L] = F2L;

   267         INSTRUCTIONS[Const.F2D] = F2D;

   268         INSTRUCTIONS[Const.D2I] = D2I;

   269         INSTRUCTIONS[Const.D2L] = D2L;

   270         INSTRUCTIONS[Const.D2F] = D2F;

   271         INSTRUCTIONS[Const.I2B] = I2B;

   272         INSTRUCTIONS[Const.I2C] = I2C;

   273         INSTRUCTIONS[Const.I2S] = I2S;

   274         INSTRUCTIONS[Const.LCMP] = LCMP;

   275         INSTRUCTIONS[Const.FCMPL] = FCMPL;

   276         INSTRUCTIONS[Const.FCMPG] = FCMPG;

   277         INSTRUCTIONS[Const.DCMPL] = DCMPL;

   278         INSTRUCTIONS[Const.DCMPG] = DCMPG;

   279         INSTRUCTIONS[Const.IRETURN] = IRETURN;

   280         INSTRUCTIONS[Const.LRETURN] = LRETURN;

   281         INSTRUCTIONS[Const.FRETURN] = FRETURN;

   282         INSTRUCTIONS[Const.DRETURN] = DRETURN;

   283         INSTRUCTIONS[Const.ARETURN] = ARETURN;

   284         INSTRUCTIONS[Const.RETURN] = RETURN;

   285         INSTRUCTIONS[Const.ARRAYLENGTH] = ARRAYLENGTH;

   286         INSTRUCTIONS[Const.ATHROW] = ATHROW;

   287         INSTRUCTIONS[Const.MONITORENTER] = MONITORENTER;

   288         INSTRUCTIONS[Const.MONITOREXIT] = MONITOREXIT;

   289     }

   290 

   291     private InstructionConst() { } // non-instantiable

   292 

   293     /**

   294      * Gets the Instruction.

   295      * @param index the index, e.g. {@link Const#RETURN}

   296      * @return the entry from the private INSTRUCTIONS table

   297      */

   298     public static Instruction getInstruction(final int index) {

   299         return INSTRUCTIONS[index];

   300     }

   301 }