hotspot/agent/src/share/classes/sun/jvm/hotspot/asm/sparc/FloatDecoder.java

/*
 * Copyright 2002 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 *
 */

package sun.jvm.hotspot.asm.sparc;

import sun.jvm.hotspot.asm.*;

abstract class FloatDecoder extends InstructionDecoder {
    final int    opf;
    final String name;
    final int    numSources; // 1 or 2;
    final int    src1Type;   // RTLDT_FL_SINGLE, _DOUBLE, _QUAD
    final int    src2Type;   // RTLDT_FL_SINGLE, _DOUBLE, _QUAD
    final int    resultType; // RTLDT_FL_SINGLE, _DOUBLE, _QUAD

    FloatDecoder(int opf, String name, int src1Type, int src2Type, int resultType) {
        this.opf = opf;
        this.name = name;
        numSources = 2;
        this.src1Type = src1Type;
        this.src2Type = src2Type;
        this.resultType = resultType;
    }

    FloatDecoder(int opf, String name, int src2Type, int resultType) {
        this.opf = opf;
        this.name = name;
        numSources = 1;
        this.src1Type = RTLOP_UNKNOWN;
        this.src2Type = src2Type;
        this.resultType = resultType;
    }

    abstract Instruction decodeFloatInstruction(int instruction,
                               SPARCRegister rs1, SPARCRegister rs2, SPARCRegister rd,
                               SPARCInstructionFactory factory);

    Instruction decode(int instruction, SPARCInstructionFactory factory) {
        int rs1Num = getSourceRegister1(instruction);
        int rs2Num = getSourceRegister2(instruction);
        int rdNum = getDestinationRegister(instruction);

        SPARCRegister rs1 = null;
        if (numSources == 2) {
           rs1 = RegisterDecoder.decode(src1Type, rs1Num);
           if (rs1 == null) {
              return factory.newIllegalInstruction(instruction);
           }
        }

        SPARCRegister rd = RegisterDecoder.decode(resultType, rdNum);
        SPARCRegister rs2 = RegisterDecoder.decode(src2Type, rs2Num);
        if (rd == null || rs2 == null) {
           return factory.newIllegalInstruction(instruction);
        }

        return decodeFloatInstruction(instruction, rs1, rs2, rd, factory);
    }
}