Example usage for org.objectweb.asm Opcodes GOTO

List of usage examples for org.objectweb.asm Opcodes GOTO

Introduction

In this page you can find the example usage for org.objectweb.asm Opcodes GOTO.

Prototype

int GOTO

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Usage

From source file:com.nginious.http.xsp.expr.MoreOperator.java

License:Apache License

/**
 * Creates bytecode for evaluating the argument values as doubles. The bytecode
 * is generated using the specified method visitor.
 * /*from  w w  w .java  2  s  .  c o  m*/
 * @param visitor the method visitor
 */
private void compileDouble(MethodVisitor visitor) {
    Label labelFalse = new Label();
    Label labelEnd = new Label();

    value1.compile(visitor, Type.DOUBLE);
    value2.compile(visitor, Type.DOUBLE);

    visitor.visitInsn(Opcodes.DCMPL);
    visitor.visitJumpInsn(Opcodes.IFLE, labelFalse);

    // True
    visitor.visitLdcInsn(true);
    visitor.visitJumpInsn(Opcodes.GOTO, labelEnd);

    // False
    visitor.visitLabel(labelFalse);
    visitor.visitLdcInsn(false);

    visitor.visitLabel(labelEnd);
}

From source file:com.nginious.http.xsp.expr.NotEqualsOperator.java

License:Apache License

/**
 * Compiles bytecode for evaluating this not equals operator producing
 * a string as result. The specified method visitor is used for generating
 * bytecode.//from ww  w.  j av  a  2  s  .co m
 * 
 * @param visitor the method visitor
 */
private void compileString(MethodVisitor visitor) {
    Label trueLabel = new Label();
    Label falseLabel = new Label();
    Label nullLabel = new Label();

    value1.compile(visitor, Type.STRING);
    visitor.visitVarInsn(Opcodes.ASTORE, 1);
    value2.compile(visitor, Type.STRING);
    visitor.visitVarInsn(Opcodes.ASTORE, 2);

    visitor.visitVarInsn(Opcodes.ALOAD, 1);
    visitor.visitJumpInsn(Opcodes.IFNULL, nullLabel);
    visitor.visitVarInsn(Opcodes.ALOAD, 2);
    visitor.visitJumpInsn(Opcodes.IFNULL, nullLabel);

    visitor.visitVarInsn(Opcodes.ALOAD, 1);
    visitor.visitVarInsn(Opcodes.ALOAD, 2);
    visitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/Object", "equals", "(Ljava/lang/Object;)Z");
    visitor.visitJumpInsn(Opcodes.IFNE, falseLabel);

    visitor.visitLabel(nullLabel);
    visitor.visitLdcInsn(true);
    visitor.visitJumpInsn(Opcodes.GOTO, trueLabel);

    visitor.visitLabel(falseLabel);
    visitor.visitLdcInsn(false);

    visitor.visitLabel(trueLabel);
}

From source file:com.nginious.http.xsp.expr.NotEqualsOperator.java

License:Apache License

/**
 * Compiles bytecode for evaluating this not equals operator producing
 * an integer as result. The specified method visitor is used for generating
 * bytecode.//www. j a va2 s . c  o m
 * 
 * @param visitor the method visitor
 */
private void compileInt(MethodVisitor visitor) {
    Label trueLabel = new Label();
    Label falseLabel = new Label();

    value1.compile(visitor, Type.INT);
    value2.compile(visitor, Type.INT);
    visitor.visitJumpInsn(Opcodes.IF_ICMPEQ, trueLabel);

    visitor.visitLdcInsn(true);
    visitor.visitJumpInsn(Opcodes.GOTO, falseLabel);

    visitor.visitLabel(trueLabel);
    visitor.visitLdcInsn(false);

    visitor.visitLabel(falseLabel);
}

From source file:com.nginious.http.xsp.expr.NotEqualsOperator.java

License:Apache License

/**
 * Compiles bytecode for evaluating this not equals operator producing
 * a double as result. The specified method visitor is used for generating
 * bytecode.//from   w w w . j a  va  2  s . c o  m
 * 
 * @param visitor the method visitor
 */
private void compileDouble(MethodVisitor visitor) {
    Label trueLabel = new Label();
    Label falseLabel = new Label();

    value1.compile(visitor, Type.DOUBLE);
    value2.compile(visitor, Type.DOUBLE);
    visitor.visitInsn(Opcodes.DCMPL);
    visitor.visitJumpInsn(Opcodes.IFEQ, trueLabel);

    visitor.visitLdcInsn(true);
    visitor.visitJumpInsn(Opcodes.GOTO, falseLabel);

    visitor.visitLabel(trueLabel);
    visitor.visitLdcInsn(false);

    visitor.visitLabel(falseLabel);
}

From source file:com.nginious.http.xsp.expr.OrOperator.java

License:Apache License

/**
 * Creates bytecode for evaluating this or operator. The bytecode is generated using
 * the specified method visitor. The result of the evaluation produces the specified
 * type./* w w  w  .j  a  v  a  2 s  .co  m*/
 * 
 * @param visitor the method visitor
 * @param type the type
 */
void compile(MethodVisitor visitor, Type type) {
    Label labelTrue = new Label();
    Label labelEnd = new Label();

    // Test first value
    value1.compile(visitor, type);
    visitor.visitInsn(Opcodes.ICONST_1);
    visitor.visitJumpInsn(Opcodes.IF_ICMPEQ, labelTrue);

    // Test second value
    value2.compile(visitor, type);
    visitor.visitInsn(Opcodes.ICONST_1);
    visitor.visitJumpInsn(Opcodes.IF_ICMPEQ, labelTrue);

    // False
    visitor.visitLdcInsn(false);
    visitor.visitJumpInsn(Opcodes.GOTO, labelEnd);

    // True
    visitor.visitLabel(labelTrue);
    visitor.visitLdcInsn(true);

    visitor.visitLabel(labelEnd);
}

From source file:com.nginious.http.xsp.expr.RightFunction.java

License:Apache License

/**
 * Creates bytecode for evaluating this right function. The specified method visitor
 * and type are used for generating bytecode.
 * //w w w .  ja  va 2s  . co m
 * @param visitor the method visitor
 * @param type the type
 */
void compile(MethodVisitor visitor, Type type) {
    value.compile(visitor, Type.STRING);
    visitor.visitVarInsn(Opcodes.ASTORE, 1);

    Label nullLabel = new Label();
    Label notNullLabel = new Label();

    visitor.visitVarInsn(Opcodes.ALOAD, 1);
    visitor.visitJumpInsn(Opcodes.IFNULL, nullLabel);

    visitor.visitVarInsn(Opcodes.ALOAD, 1);
    visitor.visitVarInsn(Opcodes.ALOAD, 1);
    visitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/String", "length", "()I");
    value2.compile(visitor, Type.INT);
    visitor.visitInsn(Opcodes.ISUB);
    visitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/String", "substring", "(I)Ljava/lang/String;");
    visitor.visitJumpInsn(Opcodes.GOTO, notNullLabel);

    visitor.visitLabel(nullLabel);
    visitor.visitInsn(Opcodes.ACONST_NULL);

    visitor.visitLabel(notNullLabel);
}

From source file:com.nginious.http.xsp.expr.SubstrFunction.java

License:Apache License

/**
 * Creates bytecode for evaluating this substring function. The specified method visitor
 * and type are used for generating bytecode.
 * /*w  w w  .  j  a v  a  2 s  .c  o m*/
 * @param visitor the method visitor
 * @param type the type
 */
void compile(MethodVisitor visitor, Type type) {
    value.compile(visitor, Type.STRING);
    visitor.visitVarInsn(Opcodes.ASTORE, 1);
    value2.compile(visitor, Type.INT);
    visitor.visitVarInsn(Opcodes.ISTORE, 2);
    value3.compile(visitor, Type.INT);
    visitor.visitVarInsn(Opcodes.ISTORE, 3);

    Label nullLabel = new Label();
    Label notNullLabel = new Label();

    // check for null string
    visitor.visitVarInsn(Opcodes.ALOAD, 1);
    visitor.visitJumpInsn(Opcodes.IFNULL, nullLabel);

    // start < 0
    Label label1 = new Label();
    visitor.visitLdcInsn(0);
    visitor.visitVarInsn(Opcodes.ILOAD, 2);
    visitor.visitJumpInsn(Opcodes.IF_ICMPLT, label1);
    visitor.visitLdcInsn(0);
    visitor.visitVarInsn(Opcodes.ISTORE, 2);

    // start > value.length
    Label label2 = new Label();
    visitor.visitLabel(label1);
    visitor.visitVarInsn(Opcodes.ALOAD, 1);
    visitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/String", "length", "()I");
    visitor.visitVarInsn(Opcodes.ILOAD, 2);
    visitor.visitJumpInsn(Opcodes.IF_ICMPGT, label2);
    visitor.visitVarInsn(Opcodes.ALOAD, 1);
    visitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/String", "length", "()I");
    visitor.visitVarInsn(Opcodes.ISTORE, 2);

    // end < start
    Label label3 = new Label();
    visitor.visitLabel(label2);
    visitor.visitVarInsn(Opcodes.ILOAD, 2);
    visitor.visitVarInsn(Opcodes.ILOAD, 3);
    visitor.visitJumpInsn(Opcodes.IF_ICMPLT, label3);
    visitor.visitVarInsn(Opcodes.ILOAD, 2);
    visitor.visitVarInsn(Opcodes.ISTORE, 3);

    // end > value1.length
    Label label4 = new Label();
    visitor.visitLabel(label3);
    visitor.visitVarInsn(Opcodes.ALOAD, 1);
    visitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/String", "length", "()I");
    visitor.visitVarInsn(Opcodes.ILOAD, 3);
    visitor.visitJumpInsn(Opcodes.IF_ICMPGT, label4);
    visitor.visitVarInsn(Opcodes.ALOAD, 1);
    visitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/String", "length", "()I");
    visitor.visitVarInsn(Opcodes.ISTORE, 3);

    // substr
    visitor.visitLabel(label4);
    visitor.visitVarInsn(Opcodes.ALOAD, 1);
    visitor.visitVarInsn(Opcodes.ILOAD, 2);
    visitor.visitVarInsn(Opcodes.ILOAD, 3);
    visitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/String", "substring", "(II)Ljava/lang/String;");
    visitor.visitJumpInsn(Opcodes.GOTO, notNullLabel);

    visitor.visitLabel(nullLabel);
    visitor.visitInsn(Opcodes.ACONST_NULL);

    visitor.visitLabel(notNullLabel);

}

From source file:com.nginious.http.xsp.ForEachTagPart.java

License:Apache License

/**
 * Creates bytecode in a separate method for evaluating this for each tag part.
 * /*from   w  w w .  j a  v a  2s  .c  om*/
 * @param intClassName the binary class name of the class being created
 * @param writer the class writer
 * @throws XspException if unable to create bytecode
 */
void compileMethod(String intClassName, ClassWriter writer) throws XspException {
    String[] exceptions = { "com/nginious/http/xsp/XspException" };
    MethodVisitor visitor = writer.visitMethod(Opcodes.ACC_PRIVATE, this.methodName,
            "(Lcom/nginious/http/HttpRequest;Lcom/nginious/http/HttpResponse;Ljava/lang/StringBuffer;)V", null,
            exceptions);
    visitor.visitCode();

    Label tryLabel = new Label();
    Label startCatchLabel = new Label();

    // Start try block
    visitor.visitTryCatchBlock(tryLabel, startCatchLabel, startCatchLabel, "java/lang/Exception");
    visitor.visitLabel(tryLabel);

    try {
        String expression = setValue.getExpressionContent();
        ExpressionParser parser = new ExpressionParser();
        TreeExpression expr = parser.parse(expression);

        if (expr.getType() != Type.ANY) {
            throw new XspException("Expression in attribute set in tag " + getName()
                    + " is not an attribute or bean property " + " at line " + getLocationDescriptor());
        }

        expr.compile(visitor, Type.ANY);
        visitor.visitTypeInsn(Opcodes.CHECKCAST, "java/util/Collection");
        visitor.visitVarInsn(Opcodes.ASTORE, 4);
    } catch (ExpressionException e) {
        throw new XspException("Invalid expression in attribute set in tag " + getName() + " at line "
                + getLocationDescriptor(), e);
    }

    Label labelOut = new Label();
    visitor.visitVarInsn(Opcodes.ALOAD, 4);
    visitor.visitJumpInsn(Opcodes.IFNULL, labelOut);

    // Start
    if (this.start != null) {
        start.compile(visitor, Type.INT);
    } else {
        visitor.visitLdcInsn((int) 0);
    }

    visitor.visitVarInsn(Opcodes.ISTORE, 5);

    // End
    if (this.end != null) {
        end.compile(visitor, Type.INT);
    } else {
        visitor.visitVarInsn(Opcodes.ALOAD, 4);
        visitor.visitMethodInsn(Opcodes.INVOKEINTERFACE, "java/util/Collection", "size", "()I");
    }

    visitor.visitVarInsn(Opcodes.ISTORE, 6);

    // Step
    if (this.step != null) {
        step.compile(visitor, Type.INT);
    } else {
        visitor.visitLdcInsn((int) 1);
    }

    visitor.visitVarInsn(Opcodes.ISTORE, 7);

    // Current pos
    visitor.visitLdcInsn(0);
    visitor.visitVarInsn(Opcodes.ISTORE, 8);

    visitor.visitVarInsn(Opcodes.ALOAD, 4);
    visitor.visitMethodInsn(Opcodes.INVOKEINTERFACE, "java/util/Collection", "iterator",
            "()Ljava/util/Iterator;");
    visitor.visitVarInsn(Opcodes.ASTORE, 9);

    Label labelStart = new Label();

    // Start of loop
    visitor.visitLabel(labelStart);

    // iterator.hasNext();
    visitor.visitVarInsn(Opcodes.ALOAD, 9);
    visitor.visitMethodInsn(Opcodes.INVOKEINTERFACE, "java/util/Iterator", "hasNext", "()Z");
    visitor.visitJumpInsn(Opcodes.IFEQ, labelOut);

    // iterator.next();
    visitor.visitVarInsn(Opcodes.ALOAD, 9);
    visitor.visitMethodInsn(Opcodes.INVOKEINTERFACE, "java/util/Iterator", "next", "()Ljava/lang/Object;");
    visitor.visitVarInsn(Opcodes.ASTORE, 10);

    // pos >= start && pos <= end && (pos - start) % step == 0
    Label labelIncr = new Label();

    visitor.visitVarInsn(Opcodes.ILOAD, 8);
    visitor.visitVarInsn(Opcodes.ILOAD, 5);
    visitor.visitJumpInsn(Opcodes.IF_ICMPLT, labelIncr);

    visitor.visitVarInsn(Opcodes.ILOAD, 8);
    visitor.visitVarInsn(Opcodes.ILOAD, 6);
    visitor.visitJumpInsn(Opcodes.IF_ICMPGT, labelIncr);

    visitor.visitVarInsn(Opcodes.ILOAD, 8);
    visitor.visitVarInsn(Opcodes.ILOAD, 5);
    visitor.visitInsn(Opcodes.ISUB);
    visitor.visitVarInsn(Opcodes.ILOAD, 7);
    visitor.visitInsn(Opcodes.IREM);
    visitor.visitJumpInsn(Opcodes.IFNE, labelIncr);

    visitor.visitVarInsn(Opcodes.ALOAD, 1);
    varName.compile(visitor, Type.STRING);
    visitor.visitVarInsn(Opcodes.ALOAD, 10);
    visitor.visitMethodInsn(Opcodes.INVOKEINTERFACE, "com/nginious/http/HttpRequest", "setAttribute",
            "(Ljava/lang/String;Ljava/lang/Object;)V");

    // Call sub parts
    for (XspPart part : this.contentParts) {
        part.compile(intClassName, writer, visitor);
    }

    // pos++
    visitor.visitLabel(labelIncr);
    visitor.visitIincInsn(8, 1);
    visitor.visitJumpInsn(Opcodes.GOTO, labelStart);

    visitor.visitLabel(labelOut);
    visitor.visitInsn(Opcodes.RETURN);

    visitor.visitLabel(startCatchLabel);

    visitor.visitVarInsn(Opcodes.ASTORE, 3);
    visitor.visitTypeInsn(Opcodes.NEW, "com/nginious/http/xsp/XspException");
    visitor.visitInsn(Opcodes.DUP);
    visitor.visitLdcInsn("Attribute set contains an invalid collection for tag " + getName() + " at "
            + getLocationDescriptor());
    visitor.visitVarInsn(Opcodes.ALOAD, 3);
    visitor.visitMethodInsn(Opcodes.INVOKESPECIAL, "com/nginious/http/xsp/XspException", "<init>",
            "(Ljava/lang/String;Ljava/lang/Throwable;)V");
    visitor.visitInsn(Opcodes.ATHROW);

    visitor.visitMaxs(11, 11);
    visitor.visitEnd();
}

From source file:com.offbynull.coroutines.instrumenter.asm.InstructionUtils.java

License:Open Source License

/**
 * Generates instructions for an unconditional jump to a label.
 * @param labelNode label to jump to//from  w ww .  j  av  a  2s .c  om
 * @throws NullPointerException if any argument is {@code null}
 * @return instructions for an unconditional jump to {@code labelNode}
 */
public static InsnList jumpTo(LabelNode labelNode) {
    Validate.notNull(labelNode);

    InsnList ret = new InsnList();
    ret.add(new JumpInsnNode(Opcodes.GOTO, labelNode));

    return ret;
}

From source file:com.offbynull.coroutines.instrumenter.asm.InstructionUtils.java

License:Open Source License

/**
 * For each element in an object array, performs an action.
 * @param counterVar parameter used to keep track of count in loop
 * @param arrayLenVar parameter used to keep track of array length
 * @param array object array instruction list -- must leave an array on top of the stack
 * @param action action to perform on each element -- element will be at top of stack and must be consumed by these instructions
 * @return instructions instruction list to perform some action if two ints are equal
 * @throws NullPointerException if any argument is {@code null}
 *///from  w w w  .  j  a va  2 s.  c  o  m
public static InsnList forEach(Variable counterVar, Variable arrayLenVar, InsnList array, InsnList action) {
    Validate.notNull(counterVar);
    Validate.notNull(arrayLenVar);
    Validate.notNull(array);
    Validate.notNull(action);
    Validate.isTrue(counterVar.getType().equals(Type.INT_TYPE));
    Validate.isTrue(arrayLenVar.getType().equals(Type.INT_TYPE));

    InsnList ret = new InsnList();

    LabelNode doneLabelNode = new LabelNode();
    LabelNode loopLabelNode = new LabelNode();

    // put zero in to counterVar
    ret.add(new LdcInsnNode(0)); // int
    ret.add(new VarInsnNode(Opcodes.ISTORE, counterVar.getIndex())); //

    // load array we'll be traversing over
    ret.add(array); // object[]

    // put array length in to arrayLenVar
    ret.add(new InsnNode(Opcodes.DUP)); // object[], object[]
    ret.add(new InsnNode(Opcodes.ARRAYLENGTH)); // object[], int
    ret.add(new VarInsnNode(Opcodes.ISTORE, arrayLenVar.getIndex())); // object[]

    // loopLabelNode: test if counterVar == arrayLenVar, if it does then jump to doneLabelNode
    ret.add(loopLabelNode);
    ret.add(new VarInsnNode(Opcodes.ILOAD, counterVar.getIndex())); // object[], int
    ret.add(new VarInsnNode(Opcodes.ILOAD, arrayLenVar.getIndex())); // object[], int, int
    ret.add(new JumpInsnNode(Opcodes.IF_ICMPEQ, doneLabelNode)); // object[]

    // load object from object[]
    ret.add(new InsnNode(Opcodes.DUP)); // object[], object[]
    ret.add(new VarInsnNode(Opcodes.ILOAD, counterVar.getIndex())); // object[], object[], int
    ret.add(new InsnNode(Opcodes.AALOAD)); // object[], object

    // call action
    ret.add(action); // object[]

    // increment counter var and goto loopLabelNode
    ret.add(new IincInsnNode(counterVar.getIndex(), 1)); // object[]
    ret.add(new JumpInsnNode(Opcodes.GOTO, loopLabelNode)); // object[]

    // doneLabelNode: pop object[] off of stack
    ret.add(doneLabelNode);
    ret.add(new InsnNode(Opcodes.POP)); //

    return ret;
}