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src/java.xml/share/classes/com/sun/org/apache/bcel/internal/generic/LocalVariableInstruction.java

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*** 1,8 **** /* ! * reserved comment block ! * DO NOT REMOVE OR ALTER! */ /* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. --- 1,7 ---- /* ! * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved. */ /* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership.
*** 16,52 **** * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ - package com.sun.org.apache.bcel.internal.generic; ! import java.io.*; import com.sun.org.apache.bcel.internal.util.ByteSequence; - import com.sun.org.apache.bcel.internal.classfile.Utility; - import com.sun.org.apache.bcel.internal.Constants; /** * Abstract super class for instructions dealing with local variables. * ! * @author <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A> */ ! public abstract class LocalVariableInstruction extends Instruction ! implements TypedInstruction, IndexedInstruction { ! protected int n = -1; // index of referenced variable private short c_tag = -1; // compact version, such as ILOAD_0 private short canon_tag = -1; // canonical tag such as ILOAD ! private final boolean wide() { return n > Constants.MAX_BYTE; } /** * Empty constructor needed for the Class.newInstance() statement in ! * Instruction.readInstruction(). Not to be used otherwise. ! * tag and length are defined in readInstruction and initFromFile, respectively. */ ! LocalVariableInstruction(short canon_tag, short c_tag) { super(); this.canon_tag = canon_tag; this.c_tag = c_tag; } --- 15,55 ---- * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.sun.org.apache.bcel.internal.generic; ! import java.io.DataOutputStream; ! import java.io.IOException; ! ! import com.sun.org.apache.bcel.internal.Const; import com.sun.org.apache.bcel.internal.util.ByteSequence; /** * Abstract super class for instructions dealing with local variables. * ! * @version $Id: LocalVariableInstruction.java 1747278 2016-06-07 17:28:43Z ! * britter $ */ ! public abstract class LocalVariableInstruction extends Instruction implements TypedInstruction, ! IndexedInstruction { ! ! private int n = -1; // index of referenced variable private short c_tag = -1; // compact version, such as ILOAD_0 private short canon_tag = -1; // canonical tag such as ILOAD ! private boolean wide() { ! return n > Const.MAX_BYTE; ! } /** * Empty constructor needed for the Class.newInstance() statement in ! * Instruction.readInstruction(). Not to be used otherwise. tag and length ! * are defined in readInstruction and initFromFile, respectively. */ ! LocalVariableInstruction(final short canon_tag, final short c_tag) { super(); this.canon_tag = canon_tag; this.c_tag = c_tag; }
*** 60,193 **** /** * @param opcode Instruction opcode * @param c_tag Instruction number for compact version, ALOAD_0, e.g. * @param n local variable index (unsigned short) */ ! protected LocalVariableInstruction(short opcode, short c_tag, int n) { ! super(opcode, (short)2); ! this.c_tag = c_tag; canon_tag = opcode; - setIndex(n); } /** * Dump instruction as byte code to stream out. * @param out Output stream */ ! public void dump(DataOutputStream out) throws IOException { ! if(wide()) // Need WIDE prefix ? ! out.writeByte(Constants.WIDE); ! ! out.writeByte(opcode); ! ! if(length > 1) { // Otherwise ILOAD_n, instruction, e.g. ! if(wide()) out.writeShort(n); ! else out.writeByte(n); } } /** * Long output format: * ! * &lt;name of opcode&gt; "["&lt;opcode number&gt;"]" ! * "("&lt;length of instruction&gt;")" "&lt;"&lt; local variable index&gt;"&gt;" * * @param verbose long/short format switch * @return mnemonic for instruction */ ! public String toString(boolean verbose) { ! if(((opcode >= Constants.ILOAD_0) && ! (opcode <= Constants.ALOAD_3)) || ! ((opcode >= Constants.ISTORE_0) && ! (opcode <= Constants.ASTORE_3))) return super.toString(verbose); ! else return super.toString(verbose) + " " + n; } /** * Read needed data (e.g. index) from file. ! * PRE: (ILOAD <= tag <= ALOAD_3) || (ISTORE <= tag <= ASTORE_3) ! */ ! protected void initFromFile(ByteSequence bytes, boolean wide) ! throws IOException ! { ! if(wide) { n = bytes.readUnsignedShort(); ! length = 4; ! } else if(((opcode >= Constants.ILOAD) && ! (opcode <= Constants.ALOAD)) || ! ((opcode >= Constants.ISTORE) && ! (opcode <= Constants.ASTORE))) { n = bytes.readUnsignedByte(); ! length = 2; ! } else if(opcode <= Constants.ALOAD_3) { // compact load instruction such as ILOAD_2 ! n = (opcode - Constants.ILOAD_0) % 4; ! length = 1; } else { // Assert ISTORE_0 <= tag <= ASTORE_3 ! n = (opcode - Constants.ISTORE_0) % 4; ! length = 1; } } /** ! * @return local variable index referred by this instruction. */ ! public final int getIndex() { return n; } /** ! * Set the local variable index */ ! public void setIndex(int n) { ! if((n < 0) || (n > Constants.MAX_SHORT)) throw new ClassGenException("Illegal value: " + n); ! this.n = n; ! ! if(n >= 0 && n <= 3) { // Use more compact instruction xLOAD_n ! opcode = (short)(c_tag + n); ! length = 1; } else { ! opcode = canon_tag; ! ! if(wide()) // Need WIDE prefix ? ! length = 4; ! else ! length = 2; } } ! /** @return canonical tag for instruction, e.g., ALOAD for ALOAD_0 */ public short getCanonicalTag() { return canon_tag; } /** ! * Returns the type associated with the instruction - ! * in case of ALOAD or ASTORE Type.OBJECT is returned. ! * This is just a bit incorrect, because ALOAD and ASTORE ! * may work on every ReferenceType (including Type.NULL) and ! * ASTORE may even work on a ReturnaddressType . * @return type associated with the instruction */ ! public Type getType(ConstantPoolGen cp) { ! switch(canon_tag) { ! case Constants.ILOAD: case Constants.ISTORE: return Type.INT; ! case Constants.LLOAD: case Constants.LSTORE: return Type.LONG; ! case Constants.DLOAD: case Constants.DSTORE: return Type.DOUBLE; ! case Constants.FLOAD: case Constants.FSTORE: return Type.FLOAT; ! case Constants.ALOAD: case Constants.ASTORE: return Type.OBJECT; ! ! default: throw new ClassGenException("Oops: unknown case in switch" + canon_tag); } } } --- 63,221 ---- /** * @param opcode Instruction opcode * @param c_tag Instruction number for compact version, ALOAD_0, e.g. * @param n local variable index (unsigned short) */ ! protected LocalVariableInstruction(final short opcode, final short c_tag, final int n) { ! super(opcode, (short) 2); this.c_tag = c_tag; canon_tag = opcode; setIndex(n); } /** * Dump instruction as byte code to stream out. + * * @param out Output stream */ ! @Override ! public void dump(final DataOutputStream out) throws IOException { ! if (wide()) { ! out.writeByte(Const.WIDE); ! } ! out.writeByte(super.getOpcode()); ! if (super.getLength() > 1) { // Otherwise ILOAD_n, instruction, e.g. ! if (wide()) { out.writeShort(n); ! } else { out.writeByte(n); } } + } /** * Long output format: * ! * &lt;name of opcode&gt; "["&lt;opcode number&gt;"]" "("&lt;length of ! * instruction&gt;")" "&lt;"&lt; local variable index&gt;"&gt;" * * @param verbose long/short format switch * @return mnemonic for instruction */ ! @Override ! public String toString(final boolean verbose) { ! final short _opcode = super.getOpcode(); ! if (((_opcode >= Const.ILOAD_0) && (_opcode <= Const.ALOAD_3)) ! || ((_opcode >= Const.ISTORE_0) && (_opcode <= Const.ASTORE_3))) { return super.toString(verbose); ! } return super.toString(verbose) + " " + n; } /** * Read needed data (e.g. index) from file. ! * <pre> ! * (ILOAD &lt;= tag &lt;= ALOAD_3) || (ISTORE &lt;= tag &lt;= ASTORE_3) ! * </pre> ! */ ! @Override ! protected void initFromFile(final ByteSequence bytes, final boolean wide) throws IOException { ! if (wide) { n = bytes.readUnsignedShort(); ! super.setLength(4); ! } else { ! final short _opcode = super.getOpcode(); ! if (((_opcode >= Const.ILOAD) && (_opcode <= Const.ALOAD)) ! || ((_opcode >= Const.ISTORE) && (_opcode <= Const.ASTORE))) { n = bytes.readUnsignedByte(); ! super.setLength(2); ! } else if (_opcode <= Const.ALOAD_3) { // compact load instruction such as ILOAD_2 ! n = (_opcode - Const.ILOAD_0) % 4; ! super.setLength(1); } else { // Assert ISTORE_0 <= tag <= ASTORE_3 ! n = (_opcode - Const.ISTORE_0) % 4; ! super.setLength(1); ! } } } /** ! * @return local variable index (n) referred by this instruction. */ ! @Override ! public final int getIndex() { ! return n; ! } /** ! * Set the local variable index. also updates opcode and length TODO Why? ! * ! * @see #setIndexOnly(int) */ ! @Override ! public void setIndex(final int n) { // TODO could be package-protected? ! if ((n < 0) || (n > Const.MAX_SHORT)) { throw new ClassGenException("Illegal value: " + n); ! } this.n = n; ! // Cannot be < 0 as this is checked above ! if (n <= 3) { // Use more compact instruction xLOAD_n ! super.setOpcode((short) (c_tag + n)); ! super.setLength(1); } else { ! super.setOpcode(canon_tag); ! if (wide()) { ! super.setLength(4); ! } else { ! super.setLength(2); ! } } } ! /** ! * @return canonical tag for instruction, e.g., ALOAD for ALOAD_0 */ public short getCanonicalTag() { return canon_tag; } /** ! * Returns the type associated with the instruction - in case of ALOAD or ! * ASTORE Type.OBJECT is returned. This is just a bit incorrect, because ! * ALOAD and ASTORE may work on every ReferenceType (including Type.NULL) ! * and ASTORE may even work on a ReturnaddressType . ! * * @return type associated with the instruction */ ! @Override ! public Type getType(final ConstantPoolGen cp) { ! switch (canon_tag) { ! case Const.ILOAD: ! case Const.ISTORE: return Type.INT; ! case Const.LLOAD: ! case Const.LSTORE: return Type.LONG; ! case Const.DLOAD: ! case Const.DSTORE: return Type.DOUBLE; ! case Const.FLOAD: ! case Const.FSTORE: return Type.FLOAT; ! case Const.ALOAD: ! case Const.ASTORE: return Type.OBJECT; ! default: ! throw new ClassGenException("Oops: unknown case in switch" + canon_tag); } } + + /** + * Sets the index of the referenced variable (n) only + * + * @since 6.0 + * @see #setIndex(int) + */ + final void setIndexOnly(final int n) { + this.n = n; + } }
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