abstractopswitch.java

一种将c高级语言转化给VHDL的编译器

/*
 *
 LA-CC 05-135 Trident 0.7.1

Copyright Notice
Copyright 2006 (c) the Regents of the University of California.

This Software was produced under a U.S. Government contract
(W-7405-ENG-36) by Los Alamos National Laboratory, which is operated
by the University of California for the U.S. Department of Energy. The
U.S. Government is licensed to use, reproduce, and distribute this
Software. Permission is granted to the public to copy and use this
Software without charge, provided that this Notice and any statement
of authorship are reproduced on all copies. Neither the Government nor
the University makes any warranty, express or implied, or assumes any
liability or responsibility for the user of this Software.

 
 */ 
package fp.circuit;

/**
 * Basic implementation of <code>OperationSwitch</code>
 *
 * @author Nathan Kitchen
 * @author Justin Tripp
 */
public abstract class AbstractOpSwitch implements OperationSwitch {
  /**
   * Holds the result of computation
   */
  private Object _result;
  
  /**
   * Sole constructor. (For invocation by subclass constructors, typically
   * implicit.) 
   */
  protected AbstractOpSwitch() {
  }

  public void caseAdd() { defaultCase(Operation.ADD); }
  public void caseAnd() { defaultCase(Operation.AND); }
  public void caseBuf() { defaultCase(Operation.BUF); }
  //public void caseDiv() { defaultCase(Operation.DIV); }
  public void caseMult() { defaultCase(Operation.MULT); }
  public void caseOr() { defaultCase(Operation.OR); }
  public void caseShl() { defaultCase(Operation.SHL); }
  public void caseShr() { defaultCase(Operation.SHR); }
  public void caseSub() { defaultCase(Operation.SUB); }
  public void caseUshr() { defaultCase(Operation.USHR); }
  public void caseXor() { defaultCase(Operation.XOR); }
  public void caseNeg() { defaultCase(Operation.NEG); }
  public void caseMux() { defaultCase(Operation.MUX); }

  public void caseExpand() { defaultCase(Operation.EXPAND); }
  public void caseConcat() { defaultCase(Operation.CONCAT); }
  public void caseSlice() { defaultCase(Operation.SLICE); }

  public void defaultCase(Operation op) { }

  /**
   * Returns the last object passed to <code>setResult</code>
   */
  public final Object getResult() {
    return _result;
  }

  /**
   * Stores <code>result</code> to be returned by the next call to
   * <code>getResult</code>.  By using these two methods together, the switch
   * can be used to compute a different result for each kind of operation.
   */
  public final void setResult(Object result) {
    _result = result;
  }
}