| /*** |
| * ASM: a very small and fast Java bytecode manipulation framework |
| * Copyright (c) 2000-2011 INRIA, France Telecom |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * 3. Neither the name of the copyright holders nor the names of its |
| * contributors may be used to endorse or promote products derived from |
| * this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE |
| * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF |
| * THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| package org.objectweb.asm.tree.analysis; |
| |
| import java.util.List; |
| |
| import org.objectweb.asm.Type; |
| import org.objectweb.asm.tree.AbstractInsnNode; |
| |
| /** |
| * A semantic bytecode interpreter. More precisely, this interpreter only |
| * manages the computation of values from other values: it does not manage the |
| * transfer of values to or from the stack, and to or from the local variables. |
| * This separation allows a generic bytecode {@link Analyzer} to work with |
| * various semantic interpreters, without needing to duplicate the code to |
| * simulate the transfer of values. |
| * |
| * @param <V> |
| * type of the Value used for the analysis. |
| * |
| * @author Eric Bruneton |
| */ |
| public abstract class Interpreter<V extends Value> { |
| |
| protected final int api; |
| |
| protected Interpreter(final int api) { |
| this.api = api; |
| } |
| |
| /** |
| * Creates a new value that represents the given type. |
| * |
| * Called for method parameters (including <code>this</code>), exception |
| * handler variable and with <code>null</code> type for variables reserved |
| * by long and double types. |
| * |
| * @param type |
| * a primitive or reference type, or <tt>null</tt> to represent |
| * an uninitialized value. |
| * @return a value that represents the given type. The size of the returned |
| * value must be equal to the size of the given type. |
| */ |
| public abstract V newValue(Type type); |
| |
| /** |
| * Interprets a bytecode instruction without arguments. This method is |
| * called for the following opcodes: |
| * |
| * ACONST_NULL, ICONST_M1, ICONST_0, ICONST_1, ICONST_2, ICONST_3, ICONST_4, |
| * ICONST_5, LCONST_0, LCONST_1, FCONST_0, FCONST_1, FCONST_2, DCONST_0, |
| * DCONST_1, BIPUSH, SIPUSH, LDC, JSR, GETSTATIC, NEW |
| * |
| * @param insn |
| * the bytecode instruction to be interpreted. |
| * @return the result of the interpretation of the given instruction. |
| * @throws AnalyzerException |
| * if an error occured during the interpretation. |
| */ |
| public abstract V newOperation(AbstractInsnNode insn) |
| throws AnalyzerException; |
| |
| /** |
| * Interprets a bytecode instruction that moves a value on the stack or to |
| * or from local variables. This method is called for the following opcodes: |
| * |
| * ILOAD, LLOAD, FLOAD, DLOAD, ALOAD, ISTORE, LSTORE, FSTORE, DSTORE, |
| * ASTORE, DUP, DUP_X1, DUP_X2, DUP2, DUP2_X1, DUP2_X2, SWAP |
| * |
| * @param insn |
| * the bytecode instruction to be interpreted. |
| * @param value |
| * the value that must be moved by the instruction. |
| * @return the result of the interpretation of the given instruction. The |
| * returned value must be <tt>equal</tt> to the given value. |
| * @throws AnalyzerException |
| * if an error occured during the interpretation. |
| */ |
| public abstract V copyOperation(AbstractInsnNode insn, V value) |
| throws AnalyzerException; |
| |
| /** |
| * Interprets a bytecode instruction with a single argument. This method is |
| * called for the following opcodes: |
| * |
| * INEG, LNEG, FNEG, DNEG, IINC, I2L, I2F, I2D, L2I, L2F, L2D, F2I, F2L, |
| * F2D, D2I, D2L, D2F, I2B, I2C, I2S, IFEQ, IFNE, IFLT, IFGE, IFGT, IFLE, |
| * TABLESWITCH, LOOKUPSWITCH, IRETURN, LRETURN, FRETURN, DRETURN, ARETURN, |
| * PUTSTATIC, GETFIELD, NEWARRAY, ANEWARRAY, ARRAYLENGTH, ATHROW, CHECKCAST, |
| * INSTANCEOF, MONITORENTER, MONITOREXIT, IFNULL, IFNONNULL |
| * |
| * @param insn |
| * the bytecode instruction to be interpreted. |
| * @param value |
| * the argument of the instruction to be interpreted. |
| * @return the result of the interpretation of the given instruction. |
| * @throws AnalyzerException |
| * if an error occured during the interpretation. |
| */ |
| public abstract V unaryOperation(AbstractInsnNode insn, V value) |
| throws AnalyzerException; |
| |
| /** |
| * Interprets a bytecode instruction with two arguments. This method is |
| * called for the following opcodes: |
| * |
| * IALOAD, LALOAD, FALOAD, DALOAD, AALOAD, BALOAD, CALOAD, SALOAD, IADD, |
| * LADD, FADD, DADD, ISUB, LSUB, FSUB, DSUB, IMUL, LMUL, FMUL, DMUL, IDIV, |
| * LDIV, FDIV, DDIV, IREM, LREM, FREM, DREM, ISHL, LSHL, ISHR, LSHR, IUSHR, |
| * LUSHR, IAND, LAND, IOR, LOR, IXOR, LXOR, LCMP, FCMPL, FCMPG, DCMPL, |
| * DCMPG, IF_ICMPEQ, IF_ICMPNE, IF_ICMPLT, IF_ICMPGE, IF_ICMPGT, IF_ICMPLE, |
| * IF_ACMPEQ, IF_ACMPNE, PUTFIELD |
| * |
| * @param insn |
| * the bytecode instruction to be interpreted. |
| * @param value1 |
| * the first argument of the instruction to be interpreted. |
| * @param value2 |
| * the second argument of the instruction to be interpreted. |
| * @return the result of the interpretation of the given instruction. |
| * @throws AnalyzerException |
| * if an error occured during the interpretation. |
| */ |
| public abstract V binaryOperation(AbstractInsnNode insn, V value1, V value2) |
| throws AnalyzerException; |
| |
| /** |
| * Interprets a bytecode instruction with three arguments. This method is |
| * called for the following opcodes: |
| * |
| * IASTORE, LASTORE, FASTORE, DASTORE, AASTORE, BASTORE, CASTORE, SASTORE |
| * |
| * @param insn |
| * the bytecode instruction to be interpreted. |
| * @param value1 |
| * the first argument of the instruction to be interpreted. |
| * @param value2 |
| * the second argument of the instruction to be interpreted. |
| * @param value3 |
| * the third argument of the instruction to be interpreted. |
| * @return the result of the interpretation of the given instruction. |
| * @throws AnalyzerException |
| * if an error occured during the interpretation. |
| */ |
| public abstract V ternaryOperation(AbstractInsnNode insn, V value1, |
| V value2, V value3) throws AnalyzerException; |
| |
| /** |
| * Interprets a bytecode instruction with a variable number of arguments. |
| * This method is called for the following opcodes: |
| * |
| * INVOKEVIRTUAL, INVOKESPECIAL, INVOKESTATIC, INVOKEINTERFACE, |
| * MULTIANEWARRAY and INVOKEDYNAMIC |
| * |
| * @param insn |
| * the bytecode instruction to be interpreted. |
| * @param values |
| * the arguments of the instruction to be interpreted. |
| * @return the result of the interpretation of the given instruction. |
| * @throws AnalyzerException |
| * if an error occured during the interpretation. |
| */ |
| public abstract V naryOperation(AbstractInsnNode insn, |
| List<? extends V> values) throws AnalyzerException; |
| |
| /** |
| * Interprets a bytecode return instruction. This method is called for the |
| * following opcodes: |
| * |
| * IRETURN, LRETURN, FRETURN, DRETURN, ARETURN |
| * |
| * @param insn |
| * the bytecode instruction to be interpreted. |
| * @param value |
| * the argument of the instruction to be interpreted. |
| * @param expected |
| * the expected return type of the analyzed method. |
| * @throws AnalyzerException |
| * if an error occured during the interpretation. |
| */ |
| public abstract void returnOperation(AbstractInsnNode insn, V value, |
| V expected) throws AnalyzerException; |
| |
| /** |
| * Merges two values. The merge operation must return a value that |
| * represents both values (for instance, if the two values are two types, |
| * the merged value must be a common super type of the two types. If the two |
| * values are integer intervals, the merged value must be an interval that |
| * contains the previous ones. Likewise for other types of values). |
| * |
| * @param v |
| * a value. |
| * @param w |
| * another value. |
| * @return the merged value. If the merged value is equal to <tt>v</tt>, |
| * this method <i>must</i> return <tt>v</tt>. |
| */ |
| public abstract V merge(V v, V w); |
| } |