mcs/class/Microsoft.JScript/Microsoft.JScript/Relational.cs

   1 //
   2 // Relational.cs:
   3 //
   4 // Author:
   5 //      Cesar Lopez Nataren (cesar@ciencias.unam.mx)
   6 //
   7 // (C) 2003, Cesar Lopez Nataren
   8 //
   9
  10 //
  11 // Permission is hereby granted, free of charge, to any person obtaining
  12 // a copy of this software and associated documentation files (the
  13 // "Software"), to deal in the Software without restriction, including
  14 // without limitation the rights to use, copy, modify, merge, publish,
  15 // distribute, sublicense, and/or sell copies of the Software, and to
  16 // permit persons to whom the Software is furnished to do so, subject to
  17 // the following conditions:
  18 //
  19 // The above copyright notice and this permission notice shall be
  20 // included in all copies or substantial portions of the Software.
  21 //
  22 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  23 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  24 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  25 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  26 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  27 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  28 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  29 //
  30
  31 using System;
  32 using System.Text;
  33 using System.Reflection;
  34 using System.Reflection.Emit;
  35
  36 namespace Microsoft.JScript {
  37
  38         public class Relational : BinaryOp {
  39
  40                 internal Relational (AST parent, AST left, AST right, JSToken op)
  41                         : base (left, right, op)
  42                 {
  43                         this.parent = parent;
  44                 }
  45
  46                 public Relational (int operatorTok)
  47                         : base (null, null, (JSToken) operatorTok)
  48                 {
  49                 }
  50
  51                 public double EvaluateRelational (object v1, object v2)
  52                 {
  53                         return -1;
  54                 }
  55
  56
  57                 public static double JScriptCompare (object v1, object v2)
  58                 {
  59                         throw new NotImplementedException ();
  60                 }
  61
  62                 public override string ToString ()
  63                 {
  64                         StringBuilder sb = new StringBuilder ();
  65
  66                         sb.Append (left.ToString ());
  67
  68                         if (op != JSToken.None)
  69                                 sb.Append (op + " ");
  70
  71                         if (right != null)
  72                                 sb.Append (right.ToString ());
  73
  74                         return sb.ToString ();
  75                 }
  76
  77                 internal override bool Resolve (IdentificationTable context)
  78                 {
  79                         if (left != null)
  80                                 left.Resolve (context);
  81
  82                         if (right != null)
  83                                 right.Resolve (context);
  84
  85                         return true;
  86                 }
  87
  88                 internal override bool Resolve (IdentificationTable context, bool no_effect)
  89                 {
  90                         this.no_effect = no_effect;
  91                         return Resolve (context);
  92                 }
  93
  94                 internal override void Emit (EmitContext ec)
  95                 {
  96                         ILGenerator ig = ec.ig;
  97
  98                         if (op == JSToken.None &&  right == null) {
  99                                 left.Emit (ec);
 100                                 return;
 101                         } else if (op == JSToken.InstanceOf) {
 102                                 if (left != null)
 103                                         left.Emit (ec);
 104                                 if (right != null)
 105                                         right.Emit (ec);
 106                                 ig.Emit (OpCodes.Call, typeof (InstanceOf).GetMethod ("JScriptInstanceof"));
 107                                 return;
 108                         } else  if (op == JSToken.In) {
 109                                 if (left != null)
 110                                         left.Emit (ec);
 111                                 if (right != null)
 112                                         right.Emit (ec);
 113                                 ig.Emit (OpCodes.Call, typeof (In).GetMethod ("JScriptIn"));
 114                                 return;
 115                         }
 116                         Type t = typeof (Relational);
 117                         LocalBuilder loc = ig.DeclareLocal (t);
 118                         ConstructorInfo ctr_info;
 119
 120                         switch (op) {
 121                         case JSToken.GreaterThan:
 122                                 ig.Emit (OpCodes.Ldc_I4_S, (byte) 57);
 123                                 break;
 124                         case JSToken.LessThan:
 125                                 ig.Emit (OpCodes.Ldc_I4_S, (byte) 58);
 126                                 break;
 127                         case JSToken.LessThanEqual:
 128                                 ig.Emit (OpCodes.Ldc_I4_S, (byte) 59);
 129                                 break;
 130                         case JSToken.GreaterThanEqual:
 131                                 ig.Emit (OpCodes.Ldc_I4_S, (byte) 60);
 132                                 break;
 133                         }
 134
 135                         ctr_info = typeof (Relational).GetConstructor (new Type [] { typeof (Int32) });
 136                         ig.Emit (OpCodes.Newobj, ctr_info);
 137                         ig.Emit (OpCodes.Stloc, loc);
 138                         ig.Emit (OpCodes.Ldloc, loc);
 139
 140                         if (left != null)
 141                                 left.Emit (ec);
 142                         if (right != null)
 143                                 right.Emit (ec);
 144
 145                         ig.Emit (OpCodes.Call, t.GetMethod ("EvaluateRelational"));
 146
 147                         if (no_effect) {
 148                                 ig.Emit (OpCodes.Ldc_I4_0);
 149                                 ig.Emit (OpCodes.Conv_R8);
 150
 151                                 Label a, b;
 152                                 a = ig.DefineLabel ();
 153                                 b = ig.DefineLabel ();
 154
 155                                 switch (op) {
 156                                 case JSToken.GreaterThan:
 157                                         ig.Emit (OpCodes.Bgt_S, a);
 158                                         break;
 159                                 case JSToken.LessThan:
 160                                         ig.Emit (OpCodes.Blt_S, a);
 161                                         break;
 162                                 case JSToken.LessThanEqual:
 163                                         ig.Emit (OpCodes.Ble_S, a);
 164                                         break;
 165                                 case JSToken.GreaterThanEqual:
 166                                         ig.Emit (OpCodes.Bge_S, a);
 167                                         break;
 168                                 }
 169
 170                                 ig.Emit (OpCodes.Ldc_I4_0);
 171                                 ig.Emit (OpCodes.Br_S, b);
 172                                 ig.MarkLabel (a);
 173                                 ig.Emit (OpCodes.Ldc_I4_1);
 174                                 ig.MarkLabel (b);
 175
 176                                 if (no_effect)
 177                                         ig.Emit (OpCodes.Pop);
 178                                 else
 179                                         ig.Emit (OpCodes.Box, typeof (bool));
 180                         }
 181                 }
 182         }
 183 }