1 /*

     2  * Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.

     8  *

     9  * This code is distributed in the hope that it will be useful, but WITHOUT

    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    12  * version 2 for more details (a copy is included in the LICENSE file that

    13  * accompanied this code).

    14  *

    15  * You should have received a copy of the GNU General Public License version

    16  * 2 along with this work; if not, write to the Free Software Foundation,

    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    18  *

    19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    20  * or visit www.oracle.com if you need additional information or have any

    21  * questions.

    22  *

    23  */

    24 

    25 package sun.jvm.hotspot.asm.sparc;

    26 

    27 import sun.jvm.hotspot.asm.*;

    28 

    29 class V9ShiftDecoder extends InstructionDecoder

    30                      implements V9InstructionDecoder {

    31     final int op3;

    32     final String name;

    33     final int rtlOperation;

    34 

    35     V9ShiftDecoder(int op3, String name, int rtlOperation) {

    36         this.op3 = op3;

    37         this.name = name;

    38         this.rtlOperation = rtlOperation;

    39     }

    40 

    41     static boolean isXBitSet(int instruction) {

    42         return (instruction & X_MASK) != 0;

    43     }

    44 

    45     Instruction decode(int instruction,

    46                        SPARCInstructionFactory factory) {

    47         SPARCRegister rs1 = SPARCRegisters.getRegister(getSourceRegister1(instruction));

    48         SPARCRegister rd = SPARCRegisters.getRegister(getDestinationRegister(instruction));

    49         boolean xBit = isXBitSet(instruction);

    50         ImmediateOrRegister operand2 = null;

    51 

    52         if (isIBitSet(instruction)) {

    53             // look for 64 bits shift operations.

    54             int value = instruction & ( xBit ? SHIFT_COUNT_6_MASK : SHIFT_COUNT_5_MASK);

    55             operand2 = new Immediate(new Short((short) value));

    56         } else {

    57             operand2 = SPARCRegisters.getRegister(getSourceRegister2(instruction));

    58         }

    59 

    60         return factory.newShiftInstruction(xBit? name + "x" : name, op3, rtlOperation, rs1, operand2, rd);

    61     }

    62 }