relation.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.util.vhdl.generator;

import java.util.*;

public class Relation extends CheckObject implements VHDLout, Operation {
  
  Object _right;
  Object _left;
  String _operator;

  static final Class[]  _classes = { 
    ShiftExpression.class,
    SimpleExpression.class, 
    Term.class, Factor.class, 
    Primary.class 
  };

  static final String[] _ops = { GE, GT, EQ, LE, LT, NE };


  public Relation(Object left, String op, Object right) {
    super(_classes, _ops, left, op, right);
  }

  public Relation(Object left) {
    this(left, null, null);
  }

  protected void addTerm(String op, Object term) { 
    if (objectAllowed(term) && operatorAllowed(op)) {
      _right = term;
      _operator = op;
    }
  }

  protected void addTerm(Object term) {
    if (objectAllowed(term)) 
      _left = term;
  }
  
  public StringBuffer toVHDL(StringBuffer s, String pre) {
    s.append(pre);
    ((VHDLout)_left).toVHDL(s,"");
    if (_operator != null) {
      s.append(" ").append(_operator);
    }
    if (_right != null) {
      s.append(" ");
      ((VHDLout)_right).toVHDL(s, "");
    }

    return s;
  }
  
  public String toString() {
    return toVHDL(new StringBuffer(), "").toString();
  }

  

   public static void main(String args[]) {
    // mult div mod rem

    SimpleName a = new SimpleName("a");
    SimpleName a1 = new SimpleName("a_1");
    SimpleName b = new SimpleName("b");
    SimpleName c = new SimpleName("c");

    System.out.println("Primaries "+a+" "+b+" "+c+"\n");

    Relation se = new Relation(a, LT, b);
    print(se);

    se = new Relation(a, GT, new Paren(new Mult(a,b)));
    print(se);

    se = new Relation(a, ROR, new Paren(new Mult(a,b)));
    print(se);

    se = new Relation(new Paren(new Add(a,b)), NE, c);
    print(se);

    se = new Relation(new Paren(new ShiftExpression(new Mult(a,b), 
						    SRL, 
						    new Paren(new Add(a,b,c)))));
    print(se);

    se = new Relation(new Div(c,b), EQ, new Mult(a,b));
    print(se);

    //Term t3 = new Div(new Paren(new Mult(a,b)), 
    //new Paren(new Mult(c,a1)));

    
  }

  public static void print(Relation f) {
    System.out.println("Relation: "+f);
  }



  
 
}