code: /**
   * Copyright (c) 2004-2005, Regents of the University of California
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * Redistributions of source code must retain the above copyright notice,
   * this list of conditions and the following disclaimer.
   *
   * Redistributions in binary form must reproduce the above copyright
   * notice, this list of conditions and the following disclaimer in the
   * documentation and/or other materials provided with the distribution.
   *
   * Neither the name of the University of California, Los Angeles nor the
   * names of its contributors may be used to endorse or promote products
   * derived from this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
   * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  package jintgen.jigir;
  
  import cck.util.Arithmetic;
  import cck.util.Util;
  import jintgen.types.*;
  
  /**
   * The <code>Arith</code> class is a container for classes that represent integer arithmetic in the IR. For
   * example, the class <code>Arith.AddExpr</code> represents an expression that is the addition of two
   * integers. The result of all operations on integers are integers, therefore, every expression that is a
   * subclass of <code>Arith</code> has a result type of integer.
   *
   * @author Ben L. Titzer
   */
  public class Arith {
  
      protected abstract static class INTINT extends BinOpExpr.BinOpImpl {
          protected INTINT(String op, int p) {
              super(op, p);
          }
          public Type typeCheck(TypeEnv env, Typeable left, Typeable right) {
              JIGIRTypeEnv jenv = (JIGIRTypeEnv)env;
              JIGIRTypeEnv.TYPE_int lt = (JIGIRTypeEnv.TYPE_int)left.getType();
              JIGIRTypeEnv.TYPE_int rt = (JIGIRTypeEnv.TYPE_int)right.getType();
              return typeCheck(jenv, lt, rt);
          }
          public Literal evaluate(Literal left, Literal right) {
              int ll = ((Literal.IntExpr)left).value;
              int lr = ((Literal.IntExpr)right).value;
              return new Literal.IntExpr(evaluate(ll, lr));
          }
          protected abstract Type typeCheck(JIGIRTypeEnv jenv, JIGIRTypeEnv.TYPE_int lt, JIGIRTypeEnv.TYPE_int rt);
          protected abstract int evaluate(int ll, int lr);
      }
  
      public static class ADD extends INTINT {
          public ADD() {
              super("+", Expr.PREC_A_ADD);
          }
          public Type typeCheck(JIGIRTypeEnv jenv, JIGIRTypeEnv.TYPE_int lt, JIGIRTypeEnv.TYPE_int rt) {
              return jenv.newIntType(lt.isSigned() || rt.isSigned(), max(lt, rt) + 1);
          }
          public int evaluate(int ll, int lr) {
              return ll + lr;
          }
      }
  
      public static class SUB extends INTINT {
          public SUB() {
              super("-", Expr.PREC_A_ADD);
          }
          public Type typeCheck(JIGIRTypeEnv jenv, JIGIRTypeEnv.TYPE_int lt, JIGIRTypeEnv.TYPE_int rt) {
              return jenv.newIntType(true, max(lt, rt) + 1);
          }
          public int evaluate(int ll, int lr) {
              return ll - lr;
          }
      }
  
      public static class MUL extends INTINT {
          public MUL() {
              super("*", Expr.PREC_A_MUL);
          }
          public Type typeCheck(JIGIRTypeEnv jenv, JIGIRTypeEnv.TYPE_int lt, JIGIRTypeEnv.TYPE_int rt) {
              return jenv.newIntType(lt.isSigned() || rt.isSigned(), lt.getSize() + rt.getSize());
          }
          public int evaluate(int ll, int lr) {
              return ll * lr;
          }
      }
  
      public static class DIV extends INTINT {
          public DIV() {
              super("/", Expr.PREC_A_MUL);
          }
          public Type typeCheck(JIGIRTypeEnv jenv, JIGIRTypeEnv.TYPE_int lt, JIGIRTypeEnv.TYPE_int rt) {
              return jenv.newIntType(lt.isSigned() || rt.isSigned(), lt.getSize());
          }
          public int evaluate(int ll, int lr) {
              return ll / lr;
          }
      }
  
      public static class MOD extends INTINT {
          public MOD() {
              super("%", Expr.PREC_A_MUL);
          }
          public Type typeCheck(JIGIRTypeEnv jenv, JIGIRTypeEnv.TYPE_int lt, JIGIRTypeEnv.TYPE_int rt) {
              return jenv.newIntType(lt.isSigned() || rt.isSigned(), lt.getSize());
          }
          public int evaluate(int ll, int lr) {
              return ll % lr;
          }
      }
  
      public static class AND extends INTINT {
          public AND() {
              super("&", Expr.PREC_A_AND);
          }
          public Type typeCheck(JIGIRTypeEnv jenv, JIGIRTypeEnv.TYPE_int lt, JIGIRTypeEnv.TYPE_int rt) {
              // TODO: is this type rule reasonable?
              return jenv.newIntType(lt.isSigned() || rt.isSigned(), max(lt, rt));
          }
          public int evaluate(int ll, int lr) {
              return ll & lr;
          }
      }
  
      public static class OR extends INTINT {
          public OR() {
              super("|", Expr.PREC_A_OR);
          }
          public Type typeCheck(JIGIRTypeEnv jenv, JIGIRTypeEnv.TYPE_int lt, JIGIRTypeEnv.TYPE_int rt) {
              // TODO: is this type rule reasonable?
              return jenv.newIntType(lt.isSigned() || rt.isSigned(), max(lt, rt));
          }
          public int evaluate(int ll, int lr) {
              return ll | lr;
          }
      }
  
      public static class XOR extends INTINT {
          public XOR() {
              super("^", Expr.PREC_A_XOR);
          }
          public Type typeCheck(JIGIRTypeEnv jenv, JIGIRTypeEnv.TYPE_int lt, JIGIRTypeEnv.TYPE_int rt) {
              // TODO: is this type rule reasonable?
              return jenv.newIntType(lt.isSigned() || rt.isSigned(), max(lt, rt));
          }
          public int evaluate(int ll, int lr) {
              return ll ^ lr;
          }
      }
  
      public static class SHL extends INTINT {
          public SHL() {
              super("<<", Expr.PREC_A_SHIFT);
          }
          public Type typeCheck(JIGIRTypeEnv jenv, JIGIRTypeEnv.TYPE_int lt, JIGIRTypeEnv.TYPE_int rt) {
              // TODO: is this type rule reasonable?
              return jenv.newIntType(lt.isSigned(), lt.getSize());
          }
          public int evaluate(int ll, int lr) {
              return ll << lr;
          }
      }
  
      public static class SHR extends INTINT {
          public SHR() {
              super(">>", Expr.PREC_A_SHIFT);
          }
          public Type typeCheck(JIGIRTypeEnv jenv, JIGIRTypeEnv.TYPE_int lt, JIGIRTypeEnv.TYPE_int rt) {
              // TODO: is this type rule reasonable?
              return jenv.newIntType(lt.isSigned(), lt.getSize());
          }
          public int evaluate(int ll, int lr) {
              return ll >> lr;
          }
      }
  
      public static class COMP extends UnOpExpr.UnOpImpl {
          public COMP() {
              super("~", Expr.PREC_UN);
          }
          public Type typeCheck(TypeEnv env, Typeable inner) {
              // JIGIRTypeEnv jenv = (JIGIRTypeEnv)env;
              return (JIGIRTypeEnv.TYPE_int)inner.getType();
          }
          public Literal evaluate(Literal inner) {
              int ll = ((Literal.IntExpr)inner).value;
              return new Literal.IntExpr(~ll);
          }
      }
  
      public static class NEG extends UnOpExpr.UnOpImpl {
          public NEG() {
              super("-", Expr.PREC_UN);
          }
          public Type typeCheck(TypeEnv env, Typeable inner) {
              JIGIRTypeEnv jenv = (JIGIRTypeEnv)env;
              JIGIRTypeEnv.TYPE_int it = (JIGIRTypeEnv.TYPE_int)inner.getType();
              return jenv.newIntType(true, it.getSize() + 1);
          }
          public Literal evaluate(Literal inner) {
              int ll = ((Literal.IntExpr)inner).value;
              return new Literal.IntExpr(-ll);
          }
      }
  
      public static class UNSIGN extends UnOpExpr.UnOpImpl {
          public UNSIGN() {
              super("+", Expr.PREC_UN);
          }
          public Type typeCheck(TypeEnv env, Typeable inner) {
              JIGIRTypeEnv jenv = (JIGIRTypeEnv)env;
              JIGIRTypeEnv.TYPE_int it = (JIGIRTypeEnv.TYPE_int)inner.getType();
              return jenv.newIntType(false, it.getSize());
          }
          public Literal evaluate(Literal inner) {
              throw Util.unimplemented();
          }
      }
  
      protected static int max(JIGIRTypeEnv.TYPE_int lt, JIGIRTypeEnv.TYPE_int rt) {
          return Arithmetic.max(lt.getSize(), rt.getSize());
      }
  }
  