mcs/class/Mono.CodeContracts/Mono.CodeContracts.Static.Analysis.ExpressionAnalysis.Expressions/BinaryExpr.cs

   1 //
   2 // BinaryExpr.cs
   3 //
   4 // Authors:
   5 //      Alexander Chebaturkin (chebaturkin@gmail.com)
   6 //
   7 // Copyright (C) 2011 Alexander Chebaturkin
   8 //
   9 // Permission is hereby granted, free of charge, to any person obtaining
  10 // a copy of this software and associated documentation files (the
  11 // "Software"), to deal in the Software without restriction, including
  12 // without limitation the rights to use, copy, modify, merge, publish,
  13 // distribute, sublicense, and/or sell copies of the Software, and to
  14 // permit persons to whom the Software is furnished to do so, subject to
  15 // the following conditions:
  16 //
  17 // The above copyright notice and this permission notice shall be
  18 // included in all copies or substantial portions of the Software.
  19 //
  20 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  21 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  22 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  23 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  24 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  25 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  26 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  27 //
  28
  29 using System;
  30 using System.Collections.Generic;
  31 using Mono.CodeContracts.Static.AST;
  32 using Mono.CodeContracts.Static.ControlFlow;
  33 using Mono.CodeContracts.Static.DataStructures;
  34
  35 namespace Mono.CodeContracts.Static.Analysis.ExpressionAnalysis.Expressions {
  36         class BinaryExpr<TSymbolicValue> : Expr<TSymbolicValue>
  37                 where TSymbolicValue : IEquatable<TSymbolicValue> {
  38
  39                 public readonly BinaryOperator Operator;
  40                 public readonly TSymbolicValue Left;
  41                 public readonly TSymbolicValue Right;
  42
  43                 public BinaryExpr (TSymbolicValue left, TSymbolicValue right, BinaryOperator op)
  44                 {
  45                         this.Left = left;
  46                         this.Right = right;
  47                         this.Operator = op;
  48                 }
  49
  50                 #region Overrides of Expression
  51                 public override IEnumerable<TSymbolicValue> Variables
  52                 {
  53                         get
  54                         {
  55                                 yield return this.Left;
  56                                 yield return this.Right;
  57                         }
  58                 }
  59
  60                 public override Result Decode<Data, Result, Visitor> (APC pc, TSymbolicValue dest, Visitor visitor, Data data)
  61                 {
  62                         return visitor.Binary (pc, this.Operator, dest, this.Left, this.Right, data);
  63                 }
  64
  65                 public override Expr<TSymbolicValue> Substitute (IImmutableMap<TSymbolicValue, Sequence<TSymbolicValue>> substitutions)
  66                 {
  67                         if (substitutions.ContainsKey (this.Left) && substitutions.ContainsKey (this.Right))
  68                                 return new BinaryExpr<TSymbolicValue> (substitutions [this.Left].Head, substitutions [this.Right].Head, this.Operator);
  69
  70                         return null;
  71                 }
  72
  73                 public override bool IsContained (IImmutableSet<TSymbolicValue> candidates)
  74                 {
  75                         return candidates.Contains (this.Left) || candidates.Contains (this.Right);
  76                 }
  77
  78                 public override bool Contains (TSymbolicValue symbol)
  79                 {
  80                         return this.Left.Equals (symbol) || this.Right.Equals (symbol);
  81                 }
  82
  83                 public override string ToString ()
  84                 {
  85                         return String.Format ("Binary({0} {1} {2})", this.Left, this.Operator, this.Right);
  86                 }
  87
  88                 public override bool Equals (Expr<TSymbolicValue> other)
  89                 {
  90                         var binary = other as BinaryExpr<TSymbolicValue>;
  91                         if (binary == null || binary.Operator != this.Operator)
  92                                 return false;
  93
  94                         return binary.Left.Equals (this.Left) && binary.Right.Equals (this.Right);
  95                 }
  96                 #endregion
  97         }
  98 }