LoadPointer.java example

Explorer
maxine-mirror-master
/*
 * Copyright (c) 2009, 2011, 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.
 *
 * 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
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */
package com.sun.c1x.ir;

import com.oracle.max.criutils.*;
import com.sun.c1x.util.*;
import com.sun.c1x.value.*;
import com.sun.cri.ci.*;
import com.sun.cri.ri.*;

/**
 * The {@code LoadPointer} instruction represents a read of a pointer.
 * This instruction is part of the HIR support for low-level operations, such as safepoints,
 * stack banging, etc, and does not correspond to a Java operation.
 */
public final class LoadPointer extends PointerOp {

    /**
     * Creates an instruction for a pointer load.
     *
     * @param dataType the type of value loaded from the pointer
     * @param opcode the opcode of the instruction
     * @param pointer the value producing the pointer
     * @param displacement the value producing the displacement. This may be {@code null}.
     * @param offsetOrIndex the value producing the scaled-index or the byte offset depending on whether {@code displacement} is {@code null}
     * @param stateBefore the state before
     * @param isVolatile {@code true} if the access is volatile
     * @see PointerOp#PointerOp(CiKind, int, Value, Value, Value, FrameState, boolean)
     */
    public LoadPointer(RiType dataType, Value pointer, Value displacement, Value offsetOrIndex, FrameState stateBefore, boolean isVolatile) {
        super(dataType.kind(false), dataType, pointer, displacement, offsetOrIndex, stateBefore, isVolatile);
    }

    @Override
    public RiResolvedType declaredType() {
        return (dataType instanceof RiResolvedType) ? (RiResolvedType) dataType : null;
    }

    @Override
    public void accept(ValueVisitor v) {
        v.visitLoadPointer(this);
    }

    @Override
    public void print(LogStream out) {
        out.print("*(").print(Util.valueString(pointer()));
        if (displacement() == null) {
            out.print(" + ").print(Util.valueString(offset()));
        } else {
            out.print(" + ").print(Util.valueString(displacement())).print(" + (").print(Util.valueString(index())).print(" * sizeOf(" + dataType + "))");
        }
        out.print(")");
    }
}