mcs/class/System.Core/System.Linq.Expressions/BinaryExpression.cs

   1 //
   2 // BinaryExpression.cs
   3 //
   4 // Author:
   5 //   Jb Evain (jbevain@novell.com)
   6 //   Miguel de Icaza (miguel@novell.com)
   7 //
   8 // Contains code from the Mono C# compiler:
   9 //   Marek Safar (marek.safar@seznam.cz)
  10 //   Martin Baulig (martin@ximian.com)
  11 //   Raja Harinath (harinath@gmail.com)
  12 //
  13 // (C) 2001-2003 Ximian, Inc.
  14 // (C) 2004-2008 Novell, Inc. (http://www.novell.com)
  15 //
  16 // Permission is hereby granted, free of charge, to any person obtaining
  17 // a copy of this software and associated documentation files (the
  18 // "Software"), to deal in the Software without restriction, including
  19 // without limitation the rights to use, copy, modify, merge, publish,
  20 // distribute, sublicense, and/or sell copies of the Software, and to
  21 // permit persons to whom the Software is furnished to do so, subject to
  22 // the following conditions:
  23 //
  24 // The above copyright notice and this permission notice shall be
  25 // included in all copies or substantial portions of the Software.
  26 //
  27 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  28 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  29 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  30 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  31 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  32 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  33 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  34 //
  35
  36 using System;
  37 using System.Reflection;
  38 using System.Reflection.Emit;
  39
  40 namespace System.Linq.Expressions {
  41
  42         public sealed class BinaryExpression : Expression {
  43
  44                 Expression left;
  45                 Expression right;
  46                 LambdaExpression conversion;
  47                 MethodInfo method;
  48                 bool lift_to_null, is_lifted;
  49
  50                 public Expression Left {
  51                         get { return left; }
  52                 }
  53
  54                 public Expression Right {
  55                         get { return right; }
  56                 }
  57
  58                 public MethodInfo Method {
  59                         get { return method; }
  60                 }
  61
  62                 public bool IsLifted {
  63                         get { return is_lifted;  }
  64                 }
  65
  66                 public bool IsLiftedToNull {
  67                         get { return lift_to_null; }
  68                 }
  69
  70                 public LambdaExpression Conversion {
  71                         get { return conversion; }
  72                 }
  73
  74                 internal BinaryExpression (ExpressionType node_type, Type type, Expression left, Expression right)
  75                         : base (node_type, type)
  76                 {
  77                         this.left = left;
  78                         this.right = right;
  79                 }
  80
  81                 internal BinaryExpression (ExpressionType node_type, Type type, Expression left, Expression right, MethodInfo method)
  82                         : base (node_type, type)
  83                 {
  84                         this.left = left;
  85                         this.right = right;
  86                         this.method = method;
  87                 }
  88
  89                 internal BinaryExpression (ExpressionType node_type, Type type, Expression left, Expression right, bool lift_to_null,
  90                         bool is_lifted, MethodInfo method, LambdaExpression conversion) : base (node_type, type)
  91                 {
  92                         this.left = left;
  93                         this.right = right;
  94                         this.method = method;
  95                         this.conversion = conversion;
  96                         this.lift_to_null = lift_to_null;
  97                         this.is_lifted = is_lifted;
  98                 }
  99
 100                 void EmitMethod (EmitContext ec)
 101                 {
 102                         left.Emit (ec);
 103                         right.Emit (ec);
 104                         ec.EmitCall (method);
 105                 }
 106
 107                 void EmitArrayAccess (EmitContext ec)
 108                 {
 109                         left.Emit (ec);
 110                         right.Emit (ec);
 111                         ec.ig.Emit (OpCodes.Ldelem, this.Type);
 112                 }
 113
 114                 void EmitLogicalBinary (EmitContext ec)
 115                 {
 116                         switch (NodeType) {
 117                         case ExpressionType.And:
 118                         case ExpressionType.Or:
 119                                 if (!IsLifted)
 120                                         EmitLogical (ec);
 121                                 else if (Type == typeof (bool?))
 122                                         EmitLiftedLogical (ec);
 123                                 else
 124                                         EmitLiftedArithmeticBinary (ec);
 125                                 break;
 126                         case ExpressionType.AndAlso:
 127                         case ExpressionType.OrElse:
 128                                 if (!IsLifted)
 129                                         EmitLogicalShortCircuit (ec);
 130                                 else
 131                                         EmitLiftedLogicalShortCircuit (ec);
 132                                 break;
 133                         }
 134                 }
 135
 136                 void EmitLogical (EmitContext ec)
 137                 {
 138                         EmitNonLiftedBinary (ec);
 139                 }
 140
 141                 void EmitLiftedLogical (EmitContext ec)
 142                 {
 143                         var ig = ec.ig;
 144                         var and = NodeType == ExpressionType.And;
 145                         var left = ec.EmitStored (this.left);
 146                         var right = ec.EmitStored (this.right);
 147
 148                         var ret_from_left = ig.DefineLabel ();
 149                         var ret_from_right = ig.DefineLabel ();
 150                         var done = ig.DefineLabel ();
 151
 152                         ec.EmitNullableGetValueOrDefault (left);
 153                         ig.Emit (OpCodes.Brtrue, ret_from_left);
 154                         ec.EmitNullableGetValueOrDefault (right);
 155                         ig.Emit (OpCodes.Brtrue, ret_from_right);
 156
 157                         ec.EmitNullableHasValue (left);
 158                         ig.Emit (OpCodes.Brfalse, ret_from_left);
 159
 160                         ig.MarkLabel (ret_from_right);
 161                         ec.EmitLoad (and ? left : right);
 162                         ig.Emit (OpCodes.Br, done);
 163
 164                         ig.MarkLabel (ret_from_left);
 165                         ec.EmitLoad (and ? right : left);
 166
 167                         ig.MarkLabel (done);
 168                 }
 169
 170                 void EmitLogicalShortCircuit (EmitContext ec)
 171                 {
 172                         var ig = ec.ig;
 173                         var and = NodeType == ExpressionType.AndAlso;
 174                         var ret = ig.DefineLabel ();
 175                         var done = ig.DefineLabel ();
 176
 177                         ec.Emit (left);
 178                         ig.Emit (and ? OpCodes.Brfalse : OpCodes.Brtrue, ret);
 179
 180                         ec.Emit (right);
 181
 182                         ig.Emit (OpCodes.Br, done);
 183
 184                         ig.MarkLabel (ret);
 185                         ig.Emit (and ? OpCodes.Ldc_I4_0 : OpCodes.Ldc_I4_1);
 186
 187                         ig.MarkLabel (done);
 188                 }
 189
 190                 void EmitLiftedLogicalShortCircuit (EmitContext ec)
 191                 {
 192                         var ig = ec.ig;
 193                         var and = NodeType == ExpressionType.AndAlso;
 194                         var left_is_null = ig.DefineLabel ();
 195                         var ret_from_left = ig.DefineLabel ();
 196                         var ret_null = ig.DefineLabel ();
 197                         var ret_new = ig.DefineLabel();
 198                         var done = ig.DefineLabel();
 199
 200                         var left = ec.EmitStored (this.left);
 201
 202                         ec.EmitNullableHasValue (left);
 203                         ig.Emit (OpCodes.Brfalse, left_is_null);
 204
 205                         ec.EmitNullableGetValueOrDefault (left);
 206
 207                         ig.Emit (OpCodes.Ldc_I4_0);
 208                         ig.Emit (OpCodes.Ceq);
 209                         ig.Emit (and ? OpCodes.Brtrue : OpCodes.Brfalse, ret_from_left);
 210
 211                         ig.MarkLabel (left_is_null);
 212                         var right = ec.EmitStored (this.right);
 213
 214                         ec.EmitNullableHasValue (right);
 215                         ig.Emit (OpCodes.Brfalse_S, ret_null);
 216
 217                         ec.EmitNullableGetValueOrDefault (right);
 218
 219                         ig.Emit (OpCodes.Ldc_I4_0);
 220                         ig.Emit (OpCodes.Ceq);
 221
 222                         ig.Emit (and ? OpCodes.Brtrue : OpCodes.Brfalse, ret_from_left);
 223
 224                         ec.EmitNullableHasValue (left);
 225                         ig.Emit (OpCodes.Brfalse, ret_null);
 226
 227                         ig.Emit (and ? OpCodes.Ldc_I4_1 : OpCodes.Ldc_I4_0);
 228                         ig.Emit (OpCodes.Br_S, ret_new);
 229
 230                         ig.MarkLabel (ret_from_left);
 231                         ig.Emit (and ? OpCodes.Ldc_I4_0 : OpCodes.Ldc_I4_1);
 232
 233                         ig.MarkLabel (ret_new);
 234                         ec.EmitNullableNew (typeof (bool?));
 235                         ig.Emit (OpCodes.Br, done);
 236
 237                         ig.MarkLabel (ret_null);
 238                         var ret = ig.DeclareLocal (typeof (bool?));
 239                         ec.EmitNullableInitialize (ret);
 240
 241                         ig.MarkLabel (done);
 242                 }
 243
 244                 void EmitCoalesce (EmitContext ec)
 245                 {
 246                         var ig = ec.ig;
 247                         var done = ig.DefineLabel ();
 248                         var load_right = ig.DefineLabel ();
 249
 250                         var left = ec.EmitStored (this.left);
 251                         if (left.LocalType.IsNullable ())
 252                                 ec.EmitNullableHasValue (left);
 253                         else
 254                                 ec.EmitLoad (left);
 255
 256                         ig.Emit (OpCodes.Brfalse, load_right);
 257
 258                         ec.EmitLoad (left);
 259                         ig.Emit (OpCodes.Br, done);
 260
 261                         ig.MarkLabel (load_right);
 262                         ec.Emit (this.right);
 263
 264                         ig.MarkLabel (done);
 265                 }
 266
 267                 static bool IsInt32OrInt64 (Type type)
 268                 {
 269                         return type == typeof (int) || type == typeof (long);
 270                 }
 271
 272                 static bool IsSingleOrDouble (Type type)
 273                 {
 274                         return type == typeof (float) || type == typeof (double);
 275                 }
 276
 277                 void EmitBinaryOperator (EmitContext ec)
 278                 {
 279                         var ig = ec.ig;
 280                         bool is_unsigned = IsUnsigned (left.Type);
 281
 282                         switch (NodeType) {
 283                         case ExpressionType.Add:
 284                                 ig.Emit (OpCodes.Add);
 285                                 break;
 286                         case ExpressionType.AddChecked:
 287                                 if (IsInt32OrInt64 (left.Type))
 288                                         ig.Emit (OpCodes.Add_Ovf);
 289                                 else
 290                                         ig.Emit (is_unsigned ? OpCodes.Add_Ovf_Un : OpCodes.Add);
 291                                 break;
 292                         case ExpressionType.Subtract:
 293                                 ig.Emit (OpCodes.Sub);
 294                                 break;
 295                         case ExpressionType.SubtractChecked:
 296                                 if (IsInt32OrInt64 (left.Type))
 297                                         ig.Emit (OpCodes.Sub_Ovf);
 298                                 else
 299                                         ig.Emit (is_unsigned ? OpCodes.Sub_Ovf_Un : OpCodes.Sub);
 300                                 break;
 301                         case ExpressionType.Multiply:
 302                                 ig.Emit (OpCodes.Mul);
 303                                 break;
 304                         case ExpressionType.MultiplyChecked:
 305                                 if (IsInt32OrInt64 (left.Type))
 306                                         ig.Emit (OpCodes.Mul_Ovf);
 307                                 else
 308                                         ig.Emit (is_unsigned ? OpCodes.Mul_Ovf_Un : OpCodes.Mul);
 309                                 break;
 310                         case ExpressionType.Divide:
 311                                 ig.Emit (is_unsigned ? OpCodes.Div_Un : OpCodes.Div);
 312                                 break;
 313                         case ExpressionType.Modulo:
 314                                 ig.Emit (is_unsigned ? OpCodes.Rem_Un : OpCodes.Rem);
 315                                 break;
 316                         case ExpressionType.RightShift:
 317                                 ig.Emit (is_unsigned ? OpCodes.Shr_Un : OpCodes.Shr);
 318                                 break;
 319                         case ExpressionType.LeftShift:
 320                                 ig.Emit (OpCodes.Shl);
 321                                 break;
 322                         case ExpressionType.And:
 323                                 ig.Emit (OpCodes.And);
 324                                 break;
 325                         case ExpressionType.Or:
 326                                 ig.Emit (OpCodes.Or);
 327                                 break;
 328                         case ExpressionType.ExclusiveOr:
 329                                 ig.Emit (OpCodes.Xor);
 330                                 break;
 331                         case ExpressionType.GreaterThan:
 332                                 ig.Emit (is_unsigned ? OpCodes.Cgt_Un : OpCodes.Cgt);
 333                                 break;
 334                         case ExpressionType.GreaterThanOrEqual:
 335                                 if (is_unsigned || IsSingleOrDouble (left.Type))
 336                                         ig.Emit (OpCodes.Clt_Un);
 337                                 else
 338                                         ig.Emit (OpCodes.Clt);
 339
 340                                 ig.Emit (OpCodes.Ldc_I4_0);
 341                                 ig.Emit (OpCodes.Ceq);
 342                                 break;
 343                         case ExpressionType.LessThan:
 344                                 ig.Emit (is_unsigned ? OpCodes.Clt_Un : OpCodes.Clt);
 345                                 break;
 346                         case ExpressionType.LessThanOrEqual:
 347                                 if (is_unsigned || IsSingleOrDouble (left.Type))
 348                                         ig.Emit (OpCodes.Cgt_Un);
 349                                 else
 350                                         ig.Emit (OpCodes.Cgt);
 351
 352                                 ig.Emit (OpCodes.Ldc_I4_0);
 353                                 ig.Emit (OpCodes.Ceq);
 354                                 break;
 355                         case ExpressionType.Equal:
 356                                 ig.Emit (OpCodes.Ceq);
 357                                 break;
 358                         case ExpressionType.NotEqual:
 359                                 ig.Emit (OpCodes.Ceq);
 360                                 ig.Emit (OpCodes.Ldc_I4_0);
 361                                 ig.Emit (OpCodes.Ceq);
 362                                 break;
 363                         case ExpressionType.Power:
 364                                 ig.Emit (OpCodes.Call, typeof (Math).GetMethod ("Pow"));
 365                                 break;
 366                         default:
 367                                 throw new InvalidOperationException (
 368                                         string.Format ("Internal error: BinaryExpression contains non-Binary nodetype {0}", NodeType));
 369                         }
 370                 }
 371
 372                 void EmitLiftedArithmeticBinary (EmitContext ec)
 373                 {
 374                         EmitLiftedToNullBinary (ec);
 375                 }
 376
 377                 void EmitLiftedToNullBinary (EmitContext ec)
 378                 {
 379                         var ig = ec.ig;
 380                         var left = ec.EmitStored (this.left);
 381                         var right = ec.EmitStored (this.right);
 382                         var result = ig.DeclareLocal (Type);
 383
 384                         var has_value = ig.DefineLabel ();
 385                         var done = ig.DefineLabel ();
 386
 387                         ec.EmitNullableHasValue (left);
 388                         ec.EmitNullableHasValue (right);
 389                         ig.Emit (OpCodes.And);
 390                         ig.Emit (OpCodes.Brtrue, has_value);
 391
 392                         ec.EmitNullableInitialize (result);
 393
 394                         ig.Emit (OpCodes.Br, done);
 395
 396                         ig.MarkLabel (has_value);
 397
 398                         ec.EmitNullableGetValueOrDefault (left);
 399                         ec.EmitNullableGetValueOrDefault (right);
 400
 401                         EmitBinaryOperator (ec);
 402
 403                         ec.EmitNullableNew (result.LocalType);
 404
 405                         ig.MarkLabel (done);
 406                 }
 407
 408                 void EmitLiftedRelationalBinary (EmitContext ec)
 409                 {
 410                         var ig = ec.ig;
 411                         var left = ec.EmitStored (this.left);
 412                         var right = ec.EmitStored (this.right);
 413
 414                         var ret = ig.DefineLabel ();
 415                         var done = ig.DefineLabel ();
 416
 417                         ec.EmitNullableGetValueOrDefault (left);
 418                         ec.EmitNullableGetValueOrDefault (right);
 419
 420                         switch (NodeType) {
 421                         case ExpressionType.Equal:
 422                         case ExpressionType.NotEqual:
 423                                 ig.Emit (OpCodes.Bne_Un, ret);
 424                                 break;
 425                         default:
 426                                 EmitBinaryOperator (ec);
 427                                 ig.Emit (OpCodes.Brfalse, ret);
 428                                 break;
 429                         }
 430
 431                         ec.EmitNullableHasValue (left);
 432                         ec.EmitNullableHasValue (right);
 433
 434                         switch (NodeType) {
 435                         case ExpressionType.Equal:
 436                                 ig.Emit (OpCodes.Ceq);
 437                                 break;
 438                         case ExpressionType.NotEqual:
 439                                 ig.Emit (OpCodes.Ceq);
 440                                 ig.Emit (OpCodes.Ldc_I4_0);
 441                                 ig.Emit (OpCodes.Ceq);
 442                                 break;
 443                         default:
 444                                 ig.Emit (OpCodes.And);
 445                                 break;
 446                         }
 447
 448                         ig.Emit (OpCodes.Br, done);
 449
 450                         ig.MarkLabel (ret);
 451
 452                         ig.Emit (NodeType == ExpressionType.NotEqual ? OpCodes.Ldc_I4_1 : OpCodes.Ldc_I4_0);
 453
 454                         ig.MarkLabel (done);
 455                 }
 456
 457                 void EmitArithmeticBinary (EmitContext ec)
 458                 {
 459                         if (!IsLifted)
 460                                 EmitNonLiftedBinary (ec);
 461                         else
 462                                 EmitLiftedArithmeticBinary (ec);
 463                 }
 464
 465                 void EmitNonLiftedBinary (EmitContext ec)
 466                 {
 467                         ec.Emit (left);
 468                         ec.Emit (right);
 469                         EmitBinaryOperator (ec);
 470                 }
 471
 472                 void EmitRelationalBinary (EmitContext ec)
 473                 {
 474                         if (!IsLifted)
 475                                 EmitNonLiftedBinary (ec);
 476                         else if (IsLiftedToNull)
 477                                 EmitLiftedToNullBinary (ec);
 478                         else
 479                                 EmitLiftedRelationalBinary (ec);
 480                 }
 481
 482                 internal override void Emit (EmitContext ec)
 483                 {
 484                         if (method != null){
 485                                 EmitMethod (ec);
 486                                 return;
 487                         }
 488
 489                         switch (NodeType){
 490                         case ExpressionType.ArrayIndex:
 491                                 EmitArrayAccess (ec);
 492                                 return;
 493                         case ExpressionType.Coalesce:
 494                                 EmitCoalesce (ec);
 495                                 return;
 496                         case ExpressionType.Power:
 497                         case ExpressionType.Add:
 498                         case ExpressionType.AddChecked:
 499                         case ExpressionType.Divide:
 500                         case ExpressionType.ExclusiveOr:
 501                         case ExpressionType.LeftShift:
 502                         case ExpressionType.Modulo:
 503                         case ExpressionType.Multiply:
 504                         case ExpressionType.MultiplyChecked:
 505                         case ExpressionType.RightShift:
 506                         case ExpressionType.Subtract:
 507                         case ExpressionType.SubtractChecked:
 508                                 EmitArithmeticBinary (ec);
 509                                 return;
 510                         case ExpressionType.Equal:
 511                         case ExpressionType.GreaterThan:
 512                         case ExpressionType.GreaterThanOrEqual:
 513                         case ExpressionType.LessThan:
 514                         case ExpressionType.LessThanOrEqual:
 515                         case ExpressionType.NotEqual:
 516                                 EmitRelationalBinary (ec);
 517                                 return;
 518                         case ExpressionType.And:
 519                         case ExpressionType.Or:
 520                         case ExpressionType.AndAlso:
 521                         case ExpressionType.OrElse:
 522                                 EmitLogicalBinary (ec);
 523                                 return;
 524                         default:
 525                                 throw new NotSupportedException (this.NodeType.ToString ());
 526                         }
 527                 }
 528         }
 529 }