1 /*
   2  * Copyright 2002 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  20  * CA 95054 USA or visit www.sun.com if you need additional information or
  21  * have any questions.
  22  *
  23  */
  24 
  25 package sun.jvm.hotspot.asm.sparc;
  26 
  27 import sun.jvm.hotspot.asm.*;
  28 
  29 abstract class MemoryInstructionDecoder extends InstructionDecoder {
  30     final int    op3;
  31     final String name;
  32     final int    dataType;
  33 
  34     SPARCRegisterIndirectAddress newRegisterIndirectAddress(SPARCRegister rs1, SPARCRegister rs2) {
  35         return new SPARCRegisterIndirectAddress(rs1, rs2);
  36     }
  37 
  38     SPARCRegisterIndirectAddress newRegisterIndirectAddress(SPARCRegister rs1, int offset) {
  39         return new SPARCRegisterIndirectAddress(rs1, offset);
  40     }
  41 
  42     static void setAddressSpace(int instruction, SPARCRegisterIndirectAddress addr) {
  43         int asi = (instruction & ASI_MASK) >>> ASI_START_BIT;
  44         addr.setAddressSpace(asi);
  45     }
  46 
  47     SPARCRegisterIndirectAddress getRegisterIndirectAddress(int instruction) {
  48         SPARCRegister rs1 = SPARCRegisters.getRegister(getSourceRegister1(instruction));
  49         boolean iBit = isIBitSet(instruction);
  50         SPARCRegisterIndirectAddress addr = null;
  51         if (iBit) {
  52             int simm13 = extractSignedIntFromNBits(instruction, 13);
  53             addr = newRegisterIndirectAddress(rs1,simm13);
  54         } else {
  55             SPARCRegister rs2 = SPARCRegisters.getRegister(getSourceRegister2(instruction));
  56             addr = newRegisterIndirectAddress(rs1,rs2);
  57         }
  58         return addr;
  59     }
  60 
  61     MemoryInstructionDecoder(int op3, String name, int dataType) {
  62         this.op3 = op3;
  63         this.name = name;
  64         this.dataType = dataType;
  65     }
  66 
  67     Instruction decode(int instruction, SPARCInstructionFactory factory) {
  68         SPARCRegisterIndirectAddress addr = getRegisterIndirectAddress(instruction);
  69         SPARCRegister rd = getDestination(instruction);
  70         boolean isV9Okay = (factory instanceof SPARCV9InstructionFactory);
  71         if ( (rd == null) || (! isV9Okay && rd.isV9Only()) )
  72             return factory.newIllegalInstruction(instruction);
  73 
  74         return decodeMemoryInstruction(instruction, addr, rd, factory);
  75     }
  76 
  77     SPARCRegister getDestination(int instruction) {
  78         int rdNum = getDestinationRegister(instruction);
  79         SPARCRegister rd = RegisterDecoder.decode(dataType, rdNum);
  80         return rd;
  81     }
  82 
  83     abstract Instruction decodeMemoryInstruction(int instruction,
  84                                    SPARCRegisterIndirectAddress addr,
  85                                    SPARCRegister rd, SPARCInstructionFactory factory);
  86 }