mcs/class/Mono.CodeContracts/Mono.CodeContracts.Static.Analysis.ExpressionAnalysis/ExprDomain.cs

   1 //
   2 // ExprDomain.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
  30 using System;
  31 using System.Collections.Generic;
  32 using System.IO;
  33 using Mono.CodeContracts.Static.Analysis.ExpressionAnalysis.Expressions;
  34 using Mono.CodeContracts.Static.DataStructures;
  35 using Mono.CodeContracts.Static.Lattices;
  36
  37 namespace Mono.CodeContracts.Static.Analysis.ExpressionAnalysis {
  38         class ExprDomain<TSymValue> : IGraph<TSymValue, Dummy>
  39                 where TSymValue : IEquatable<TSymValue> {
  40                 private readonly EnvironmentDomain<TSymValue, FlatDomain<Expr<TSymValue>>> expressions;
  41
  42                 private ExprDomain (EnvironmentDomain<TSymValue, FlatDomain<Expr<TSymValue>>> expressions)
  43                 {
  44                         this.expressions = expressions;
  45                 }
  46
  47                 #region Implementation of IGraph<SymbolicValue,Dummy>
  48                 public IEnumerable<TSymValue> Keys
  49                 {
  50                         get { return this.expressions.Keys; }
  51                 }
  52
  53                 public bool IsBottom
  54                 {
  55                         get { return this.expressions.IsBottom; }
  56                 }
  57
  58                 IEnumerable<TSymValue> IGraph<TSymValue, Dummy>.Nodes
  59                 {
  60                         get { return this.expressions.Keys; }
  61                 }
  62
  63                 public IEnumerable<Pair<Dummy, TSymValue>> Successors(TSymValue node)
  64                 {
  65                         FlatDomain<Expr<TSymValue>> expr = this.expressions[node];
  66                         if (expr.IsNormal) foreach (TSymValue sv in expr.Concrete.Variables) yield return new Pair<Dummy, TSymValue> (Dummy.Value, sv);
  67                 }
  68                 #endregion
  69
  70                 public FlatDomain<Expr<TSymValue>> this[TSymValue sv]
  71                 {
  72                         get { return this.expressions[sv]; }
  73                 }
  74
  75                 public ExprDomain<TSymValue> Join(ExprDomain<TSymValue> that, bool widening, out bool weaker)
  76                 {
  77                         return new ExprDomain<TSymValue> (this.expressions.Join (that.expressions, widening, out weaker));
  78                 }
  79
  80                 public static ExprDomain<TSymValue> TopValue(Func<TSymValue, int> keyConverter )
  81                 {
  82                         return new ExprDomain<TSymValue> (EnvironmentDomain<TSymValue, FlatDomain<Expr<TSymValue>>>.TopValue (keyConverter));
  83                 }
  84
  85                 public ExprDomain<TSymValue> Add (TSymValue sv, Expr<TSymValue> expr)
  86                 {
  87                         return new ExprDomain<TSymValue> (this.expressions.Add (sv, expr));
  88                 }
  89
  90                 public ExprDomain<TSymValue> Remove(TSymValue sv)
  91                 {
  92                         return new ExprDomain<TSymValue> (this.expressions.Remove (sv));
  93                 }
  94
  95                 public ExprDomain<TSymValue> Empty()
  96                 {
  97                         return new ExprDomain<TSymValue> (this.expressions.Empty ());
  98                 }
  99
 100                 public bool HasRefinement(TSymValue sv)
 101                 {
 102                         return this.expressions.Contains (sv);
 103                 }
 104
 105                 public bool IsReachableFrom(TSymValue source, TSymValue target)
 106                 {
 107                         bool reachable = false;
 108                         DepthFirst.Visit (this, source, sv => {
 109                                                                 if (sv.Equals (target))
 110                                                                         reachable = true;
 111                                                                 return true;
 112                                                         }, null);
 113                         return reachable;
 114                 }
 115
 116                 public void Dump(TextWriter tw)
 117                 {
 118                         this.expressions.Dump (tw);
 119                 }
 120         }
 121 }