ShiftRightExpression.java

/*
 * Copyright (c) 1994, 2003, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package sun.tools.tree;
import sun.tools.java.*;
import sun.tools.asm.Assembler;

/**
 * WARNING: The contents of this source file are not part of any
 * supported API.  Code that depends on them does so at its own risk:
 * they are subject to change or removal without notice.
 */
public
class ShiftRightExpression extends BinaryShiftExpression {
    /**
     * constructor
     */
    public ShiftRightExpression(long where, Expression left, Expression right) {
	super(RSHIFT, where, left, right);
    }

    /**
     * Evaluate
     */
    Expression eval(int a, int b) {
	return new IntExpression(where, a >> b);
    }
    Expression eval(long a, long b) {
	return new LongExpression(where, a >> b);
    }

    /**
     * Simplify
     */
    Expression simplify() {
	if (right.equals(0)) {
	    return left;
	}
	if (left.equals(0)) {
	    return new CommaExpression(where, right, left).simplify();
	}
	return this;
    }

    /**
     * Code
     */
    void codeOperation(Environment env, Context ctx, Assembler asm) {
	asm.add(where, opc_ishr + type.getTypeCodeOffset());
    }
}