LWC1.java

/*
 * LWC1.java
 *
 * 25th may 2006
 * Instruction LW of the MIPS64 Instruction Set
 * (c) 2006 EduMips64 project - Trubia Massimo
 *
 * This file is part of the EduMIPS64 project, and is released under the GNU
 * General Public License.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

package org.edumips64.core.is;
import org.edumips64.core.*;
import org.edumips64.utils.*;


/**
  * <pre>
 *      Format: LWC1 ft, offset(base)
 * Description: To load a word from memory to an FPR
 *   Operation: ft = readmemoryword[base+offset]
 *</pre>

 */
class LWC1 extends FPLoading {
  final String OPCODE_VALUE = "110001";
  LWC1(Memory memory) {
    super(memory);
    super.OPCODE_VALUE = OPCODE_VALUE;
    this.name = "LWC1";
  }


  public void MEM() throws IrregularStringOfBitsException, NotAlignException, MemoryElementNotFoundException, AddressErrorException, IrregularWriteOperationException {
    super.MEM(); //unlock the fp register in order to avoid WAW hazards
    //restoring the address from the temporary register
    long address = TR[OFFSET_PLUS_BASE].getValue();
    //For the trace file
    dinero.Load(Converter.binToHex(Converter.positiveIntToBin(64, address)), 4);
    MemoryElement memEl = memory.getCellByAddress(address);
    //reading from the memory element and saving values on LMD register
    TR[LMD_REGISTER].writeWord(memEl.readWord((int)(address % 8)));

    if (cpu.isEnableForwarding()) {
      doWB();
    }
  }
}