mcs/class/corlib/System.Reflection.Emit/ILGenerator.cs

   1
   2 //
   3 // Copyright (C) 2004 Novell, Inc (http://www.novell.com)
   4 //
   5 // Permission is hereby granted, free of charge, to any person obtaining
   6 // a copy of this software and associated documentation files (the
   7 // "Software"), to deal in the Software without restriction, including
   8 // without limitation the rights to use, copy, modify, merge, publish,
   9 // distribute, sublicense, and/or sell copies of the Software, and to
  10 // permit persons to whom the Software is furnished to do so, subject to
  11 // the following conditions:
  12 //
  13 // The above copyright notice and this permission notice shall be
  14 // included in all copies or substantial portions of the Software.
  15 //
  16 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  17 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  18 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  19 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  20 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  21 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  22 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  23 //
  24
  25 //
  26 // System.Reflection.Emit/ILGenerator.cs
  27 //
  28 // Author:
  29 //   Paolo Molaro (lupus@ximian.com)
  30 //
  31 // (C) 2001 Ximian, Inc.  http://www.ximian.com
  32 //
  33
  34 using System;
  35 using System.Collections;
  36 using System.Diagnostics.SymbolStore;
  37 using System.Runtime.InteropServices;
  38
  39 namespace System.Reflection.Emit {
  40
  41         internal struct ILExceptionBlock {
  42                 public const int CATCH = 0;
  43                 public const int FILTER = 1;
  44                 public const int FINALLY = 2;
  45                 public const int FAULT = 4;
  46
  47                 internal Type extype;
  48                 internal int type;
  49                 internal int start;
  50                 internal int len;
  51                 internal int filter_offset;
  52
  53                 internal void Debug () {
  54 #if NO
  55                         System.Console.Write ("\ttype="+type.ToString()+" start="+start.ToString()+" len="+len.ToString());
  56                         if (extype != null)
  57                                 System.Console.WriteLine (" extype="+extype.ToString());
  58                         else
  59                                 System.Console.WriteLine ("");
  60 #endif
  61                 }
  62         }
  63         internal struct ILExceptionInfo {
  64                 ILExceptionBlock[] handlers;
  65                 internal int start;
  66                 int len;
  67                 internal Label end;
  68
  69                 internal int NumHandlers ()
  70                 {
  71                         return handlers.Length;
  72                 }
  73
  74                 internal void AddCatch (Type extype, int offset)
  75                 {
  76                         int i;
  77                         End (offset);
  78                         add_block (offset);
  79                         i = handlers.Length - 1;
  80                         handlers [i].type = ILExceptionBlock.CATCH;
  81                         handlers [i].start = offset;
  82                         handlers [i].extype = extype;
  83                 }
  84
  85                 internal void AddFinally (int offset)
  86                 {
  87                         int i;
  88                         End (offset);
  89                         add_block (offset);
  90                         i = handlers.Length - 1;
  91                         handlers [i].type = ILExceptionBlock.FINALLY;
  92                         handlers [i].start = offset;
  93                         handlers [i].extype = null;
  94                 }
  95
  96                 internal void AddFault (int offset)
  97                 {
  98                         int i;
  99                         End (offset);
 100                         add_block (offset);
 101                         i = handlers.Length - 1;
 102                         handlers [i].type = ILExceptionBlock.FAULT;
 103                         handlers [i].start = offset;
 104                         handlers [i].extype = null;
 105                 }
 106
 107                 internal void AddFilter (int offset)
 108                 {
 109                         int i;
 110                         End (offset);
 111                         add_block (offset);
 112                         i = handlers.Length - 1;
 113                         handlers [i].type = ILExceptionBlock.FILTER;
 114                         handlers [i].extype = null;
 115                         handlers [i].filter_offset = offset;
 116                 }
 117
 118                 internal void End (int offset)
 119                 {
 120                         if (handlers == null)
 121                                 return;
 122                         int i = handlers.Length - 1;
 123                         if (i >= 0)
 124                                 handlers [i].len = offset - handlers [i].start;
 125                 }
 126
 127                 internal int LastClauseType ()
 128                 {
 129                         if (handlers != null)
 130                                 return handlers [handlers.Length-1].type;
 131                         else
 132                                 return ILExceptionBlock.CATCH;
 133                 }
 134
 135                 internal void PatchLastClauseStart (int start)
 136                 {
 137                         if (handlers != null && handlers.Length > 0)
 138                                 handlers [handlers.Length - 1].start = start;
 139                 }
 140
 141                 internal void Debug (int b)
 142                 {
 143 #if NO
 144                         System.Console.WriteLine ("Handler {0} at {1}, len: {2}", b, start, len);
 145                         for (int i = 0; i < handlers.Length; ++i)
 146                                 handlers [i].Debug ();
 147 #endif
 148                 }
 149
 150                 void add_block (int offset)
 151                 {
 152                         if (handlers != null) {
 153                                 int i = handlers.Length;
 154                                 ILExceptionBlock[] new_b = new ILExceptionBlock [i + 1];
 155                                 System.Array.Copy (handlers, new_b, i);
 156                                 handlers = new_b;
 157                                 handlers [i].len = offset - handlers [i].start;
 158                         } else {
 159                                 handlers = new ILExceptionBlock [1];
 160                                 len = offset - start;
 161                         }
 162                 }
 163         }
 164
 165         internal struct ILTokenInfo {
 166                 public MemberInfo member;
 167                 public int code_pos;
 168         }
 169
 170         internal interface TokenGenerator {
 171                 int GetToken (string str);
 172
 173                 int GetToken (MemberInfo member);
 174
 175                 int GetToken (MethodInfo method, Type[] opt_param_types);
 176
 177                 int GetToken (SignatureHelper helper);
 178         }
 179
 180 #if NET_2_0
 181         [ComVisible (true)]
 182 #endif
 183         [ClassInterface (ClassInterfaceType.None)]
 184         public class ILGenerator: _ILGenerator {
 185                 private struct LabelFixup {
 186                         public int offset;    // The number of bytes between pos and the
 187                                                               // offset of the jump
 188                         public int pos;       // Where offset of the label is placed
 189                         public int label_idx; // The label to jump to
 190                 };
 191
 192                 struct LabelData {
 193                         public LabelData (int addr, int maxStack)
 194                         {
 195                                 this.addr = addr;
 196                                 this.maxStack = maxStack;
 197                         }
 198
 199                         public int addr;
 200                         public int maxStack;
 201                 }
 202
 203                 static readonly Type void_type = typeof (void);
 204                 #region Sync with reflection.h
 205                 private byte[] code;
 206                 private int code_len;
 207                 private int max_stack;
 208                 private int cur_stack;
 209                 private LocalBuilder[] locals;
 210                 private ILExceptionInfo[] ex_handlers;
 211                 private int num_token_fixups;
 212                 private ILTokenInfo[] token_fixups;
 213                 #endregion
 214
 215                 private LabelData [] labels;
 216                 private int num_labels;
 217                 private LabelFixup[] fixups;
 218                 private int num_fixups;
 219                 internal Module module;
 220                 private Stack scopes;
 221                 private int cur_block;
 222                 private Stack open_blocks;
 223                 private TokenGenerator token_gen;
 224
 225                 const int defaultFixupSize = 8;
 226                 const int defaultLabelsSize = 8;
 227                 ArrayList sequencePointLists;
 228                 SequencePointList currentSequence;
 229
 230                 internal ILGenerator (Module m, TokenGenerator token_gen, int size)
 231                 {
 232                         if (size < 0)
 233                                 size = 128;
 234                         code_len = 0;
 235                         code = new byte [size];
 236                         cur_stack = max_stack = 0;
 237                         num_fixups = num_labels = 0;
 238                         token_fixups = new ILTokenInfo [8];
 239                         num_token_fixups = 0;
 240                         module = m;
 241                         open_blocks = new Stack ();
 242                         this.token_gen = token_gen;
 243                 }
 244
 245                 private void add_token_fixup (MemberInfo mi)
 246                 {
 247                         if (num_token_fixups == token_fixups.Length) {
 248                                 ILTokenInfo[] ntf = new ILTokenInfo [num_token_fixups * 2];
 249                                 token_fixups.CopyTo (ntf, 0);
 250                                 token_fixups = ntf;
 251                         }
 252                         token_fixups [num_token_fixups].member = mi;
 253                         token_fixups [num_token_fixups++].code_pos = code_len;
 254                 }
 255
 256                 private void make_room (int nbytes)
 257                 {
 258                         if (code_len + nbytes < code.Length)
 259                                 return;
 260                         byte[] new_code = new byte [(code_len + nbytes) * 2 + 128];
 261                         System.Array.Copy (code, 0, new_code, 0, code.Length);
 262                         code = new_code;
 263                 }
 264
 265                 private void emit_int (int val)
 266                 {
 267                         code [code_len++] = (byte) (val & 0xFF);
 268                         code [code_len++] = (byte) ((val >> 8) & 0xFF);
 269                         code [code_len++] = (byte) ((val >> 16) & 0xFF);
 270                         code [code_len++] = (byte) ((val >> 24) & 0xFF);
 271                 }
 272
 273                 /* change to pass by ref to avoid copy */
 274                 private void ll_emit (OpCode opcode)
 275                 {
 276                         /*
 277                          * there is already enough room allocated in code.
 278                          */
 279                         // access op1 and op2 directly since the Value property is useless
 280                         if (opcode.Size == 2)
 281                                 code [code_len++] = opcode.op1;
 282                         code [code_len++] = opcode.op2;
 283                         /*
 284                          * We should probably keep track of stack needs here.
 285                          * Or we may want to run the verifier on the code before saving it
 286                          * (this may be needed anyway when the ILGenerator is not used...).
 287                          */
 288                         switch (opcode.StackBehaviourPush) {
 289                         case StackBehaviour.Push1:
 290                         case StackBehaviour.Pushi:
 291                         case StackBehaviour.Pushi8:
 292                         case StackBehaviour.Pushr4:
 293                         case StackBehaviour.Pushr8:
 294                         case StackBehaviour.Pushref:
 295                         case StackBehaviour.Varpush: /* again we are conservative and assume it pushes 1 */
 296                                 cur_stack ++;
 297                                 break;
 298                         case StackBehaviour.Push1_push1:
 299                                 cur_stack += 2;
 300                                 break;
 301                         }
 302                         if (max_stack < cur_stack)
 303                                 max_stack = cur_stack;
 304
 305                         /*
 306                          * Note that we adjust for the pop behaviour _after_ setting max_stack.
 307                          */
 308                         switch (opcode.StackBehaviourPop) {
 309                         case StackBehaviour.Varpop:
 310                                 break; /* we are conservative and assume it doesn't decrease the stack needs */
 311                         case StackBehaviour.Pop1:
 312                         case StackBehaviour.Popi:
 313                         case StackBehaviour.Popref:
 314                                 cur_stack --;
 315                                 break;
 316                         case StackBehaviour.Pop1_pop1:
 317                         case StackBehaviour.Popi_pop1:
 318                         case StackBehaviour.Popi_popi:
 319                         case StackBehaviour.Popi_popi8:
 320                         case StackBehaviour.Popi_popr4:
 321                         case StackBehaviour.Popi_popr8:
 322                         case StackBehaviour.Popref_pop1:
 323                         case StackBehaviour.Popref_popi:
 324                                 cur_stack -= 2;
 325                                 break;
 326                         case StackBehaviour.Popi_popi_popi:
 327                         case StackBehaviour.Popref_popi_popi:
 328                         case StackBehaviour.Popref_popi_popi8:
 329                         case StackBehaviour.Popref_popi_popr4:
 330                         case StackBehaviour.Popref_popi_popr8:
 331                         case StackBehaviour.Popref_popi_popref:
 332                                 cur_stack -= 3;
 333                                 break;
 334                         }
 335                 }
 336
 337                 private static int target_len (OpCode opcode)
 338                 {
 339                         if (opcode.OperandType == OperandType.InlineBrTarget)
 340                                 return 4;
 341                         return 1;
 342                 }
 343
 344                 private void InternalEndClause ()
 345                 {
 346                         switch (ex_handlers [cur_block].LastClauseType ()) {
 347                         case ILExceptionBlock.CATCH:
 348                         case ILExceptionBlock.FILTER:
 349                                 // how could we optimize code size here?
 350                                 Emit (OpCodes.Leave, ex_handlers [cur_block].end);
 351                                 break;
 352                         case ILExceptionBlock.FAULT:
 353                         case ILExceptionBlock.FINALLY:
 354                                 Emit (OpCodes.Endfinally);
 355                                 break;
 356                         }
 357                 }
 358
 359                 public virtual void BeginCatchBlock (Type exceptionType)
 360                 {
 361                         if (open_blocks.Count <= 0)
 362                                 throw new NotSupportedException ("Not in an exception block");
 363
 364                         if (ex_handlers [cur_block].LastClauseType () == ILExceptionBlock.FILTER) {
 365                                 if (exceptionType != null)
 366                                         throw new ArgumentException ("Do not supply an exception type for filter clause");
 367                                 Emit (OpCodes.Endfilter);
 368                                 ex_handlers [cur_block].PatchLastClauseStart (code_len);
 369                         } else {
 370                                 InternalEndClause ();
 371                                 ex_handlers [cur_block].AddCatch (exceptionType, code_len);
 372                         }
 373
 374                         cur_stack = 1; // the exception object is on the stack by default
 375                         if (max_stack < cur_stack)
 376                                 max_stack = cur_stack;
 377
 378                         //System.Console.WriteLine ("Begin catch Block: {0} {1}",exceptionType.ToString(), max_stack);
 379                 }
 380
 381                 public virtual void BeginExceptFilterBlock ()
 382                 {
 383                         if (open_blocks.Count <= 0)
 384                                 throw new NotSupportedException ("Not in an exception block");
 385                         InternalEndClause ();
 386
 387                         ex_handlers [cur_block].AddFilter (code_len);
 388                 }
 389
 390                 public virtual Label BeginExceptionBlock ()
 391                 {
 392                         //System.Console.WriteLine ("Begin Block");
 393
 394                         if (ex_handlers != null) {
 395                                 cur_block = ex_handlers.Length;
 396                                 ILExceptionInfo[] new_ex = new ILExceptionInfo [cur_block + 1];
 397                                 System.Array.Copy (ex_handlers, new_ex, cur_block);
 398                                 ex_handlers = new_ex;
 399                         } else {
 400                                 ex_handlers = new ILExceptionInfo [1];
 401                                 cur_block = 0;
 402                         }
 403                         open_blocks.Push (cur_block);
 404                         ex_handlers [cur_block].start = code_len;
 405                         return ex_handlers [cur_block].end = DefineLabel ();
 406                 }
 407
 408                 public virtual void BeginFaultBlock()
 409                 {
 410                         if (open_blocks.Count <= 0)
 411                                 throw new NotSupportedException ("Not in an exception block");
 412                         InternalEndClause ();
 413                         //System.Console.WriteLine ("Begin fault Block");
 414                         ex_handlers [cur_block].AddFault (code_len);
 415                 }
 416
 417                 public virtual void BeginFinallyBlock()
 418                 {
 419                         if (open_blocks.Count <= 0)
 420                                 throw new NotSupportedException ("Not in an exception block");
 421                         InternalEndClause ();
 422                         //System.Console.WriteLine ("Begin finally Block");
 423                         ex_handlers [cur_block].AddFinally (code_len);
 424                 }
 425
 426                 public virtual void BeginScope ()
 427                 { }
 428
 429                 public LocalBuilder DeclareLocal (Type localType)
 430                 {
 431                         return DeclareLocal (localType, false);
 432                 }
 433
 434
 435 #if NET_2_0
 436                 public
 437 #else
 438                 internal
 439 #endif
 440                 LocalBuilder DeclareLocal (Type localType, bool pinned)
 441                 {
 442                         if (localType == null)
 443                                 throw new ArgumentNullException ("localType");
 444
 445                         LocalBuilder res = new LocalBuilder (localType, this);
 446                         res.is_pinned = pinned;
 447
 448                         if (locals != null) {
 449                                 LocalBuilder[] new_l = new LocalBuilder [locals.Length + 1];
 450                                 System.Array.Copy (locals, new_l, locals.Length);
 451                                 new_l [locals.Length] = res;
 452                                 locals = new_l;
 453                         } else {
 454                                 locals = new LocalBuilder [1];
 455                                 locals [0] = res;
 456                         }
 457                         res.position = (ushort)(locals.Length - 1);
 458                         return res;
 459                 }
 460
 461                 public virtual Label DefineLabel ()
 462                 {
 463                         if (labels == null)
 464                                 labels = new LabelData [defaultLabelsSize];
 465                         else if (num_labels >= labels.Length) {
 466                                 LabelData [] t = new LabelData [labels.Length * 2];
 467                                 Array.Copy (labels, t, labels.Length);
 468                                 labels = t;
 469                         }
 470
 471                         labels [num_labels] = new LabelData (-1, 0);
 472
 473                         return new Label (num_labels++);
 474                 }
 475
 476                 public virtual void Emit (OpCode opcode)
 477                 {
 478                         make_room (2);
 479                         ll_emit (opcode);
 480                 }
 481
 482                 public virtual void Emit (OpCode opcode, Byte val)
 483                 {
 484                         make_room (3);
 485                         ll_emit (opcode);
 486                         code [code_len++] = val;
 487                 }
 488
 489 #if NET_2_0
 490                 [ComVisible (true)]
 491 #endif
 492                 public virtual void Emit (OpCode opcode, ConstructorInfo constructor)
 493                 {
 494                         int token = token_gen.GetToken (constructor);
 495                         make_room (6);
 496                         ll_emit (opcode);
 497                         if (constructor.DeclaringType.Module == module)
 498                                 add_token_fixup (constructor);
 499                         emit_int (token);
 500
 501                         if (opcode.StackBehaviourPop == StackBehaviour.Varpop)
 502                                 cur_stack -= constructor.GetParameterCount ();
 503                 }
 504
 505                 public virtual void Emit (OpCode opcode, double val)
 506                 {
 507                         Double.AssertEndianity (out val);
 508
 509                         byte[] s = System.BitConverter.GetBytes (val);
 510                         make_room (10);
 511                         ll_emit (opcode);
 512                         if (BitConverter.IsLittleEndian){
 513                                 System.Array.Copy (s, 0, code, code_len, 8);
 514                                 code_len += 8;
 515                         } else {
 516                                 code [code_len++] = s [7];
 517                                 code [code_len++] = s [6];
 518                                 code [code_len++] = s [5];
 519                                 code [code_len++] = s [4];
 520                                 code [code_len++] = s [3];
 521                                 code [code_len++] = s [2];
 522                                 code [code_len++] = s [1];
 523                                 code [code_len++] = s [0];
 524                         }
 525                 }
 526
 527                 public virtual void Emit (OpCode opcode, FieldInfo field)
 528                 {
 529                         int token = token_gen.GetToken (field);
 530                         make_room (6);
 531                         ll_emit (opcode);
 532                         if (field.DeclaringType.Module == module)
 533                                 add_token_fixup (field);
 534                         emit_int (token);
 535                 }
 536
 537                 public virtual void Emit (OpCode opcode, Int16 val)
 538                 {
 539                         make_room (4);
 540                         ll_emit (opcode);
 541                         code [code_len++] = (byte) (val & 0xFF);
 542                         code [code_len++] = (byte) ((val >> 8) & 0xFF);
 543                 }
 544
 545                 public virtual void Emit (OpCode opcode, int val)
 546                 {
 547                         make_room (6);
 548                         ll_emit (opcode);
 549                         emit_int (val);
 550                 }
 551
 552                 public virtual void Emit (OpCode opcode, long val)
 553                 {
 554                         make_room (10);
 555                         ll_emit (opcode);
 556                         code [code_len++] = (byte) (val & 0xFF);
 557                         code [code_len++] = (byte) ((val >> 8) & 0xFF);
 558                         code [code_len++] = (byte) ((val >> 16) & 0xFF);
 559                         code [code_len++] = (byte) ((val >> 24) & 0xFF);
 560                         code [code_len++] = (byte) ((val >> 32) & 0xFF);
 561                         code [code_len++] = (byte) ((val >> 40) & 0xFF);
 562                         code [code_len++] = (byte) ((val >> 48) & 0xFF);
 563                         code [code_len++] = (byte) ((val >> 56) & 0xFF);
 564                 }
 565
 566                 public virtual void Emit (OpCode opcode, Label label)
 567                 {
 568                         int tlen = target_len (opcode);
 569                         make_room (6);
 570                         ll_emit (opcode);
 571                         if (cur_stack > labels [label.label].maxStack)
 572                                 labels [label.label].maxStack = cur_stack;
 573
 574                         if (fixups == null)
 575                                 fixups = new LabelFixup [defaultFixupSize];
 576                         else if (num_fixups >= fixups.Length) {
 577                                 LabelFixup[] newf = new LabelFixup [fixups.Length + 16];
 578                                 System.Array.Copy (fixups, newf, fixups.Length);
 579                                 fixups = newf;
 580                         }
 581                         fixups [num_fixups].offset = tlen;
 582                         fixups [num_fixups].pos = code_len;
 583                         fixups [num_fixups].label_idx = label.label;
 584                         num_fixups++;
 585                         code_len += tlen;
 586
 587                 }
 588
 589                 public virtual void Emit (OpCode opcode, Label[] labels)
 590                 {
 591                         /* opcode needs to be switch. */
 592                         int count = labels.Length;
 593                         make_room (6 + count * 4);
 594                         ll_emit (opcode);
 595
 596                         for (int i = 0; i < count; ++i)
 597                                 if (cur_stack > this.labels [labels [i].label].maxStack)
 598                                         this.labels [labels [i].label].maxStack = cur_stack;
 599
 600                         emit_int (count);
 601                         if (fixups == null)
 602                                 fixups = new LabelFixup [defaultFixupSize + count];
 603                         else if (num_fixups + count >= fixups.Length) {
 604                                 LabelFixup[] newf = new LabelFixup [fixups.Length + count + 16];
 605                                 System.Array.Copy (fixups, newf, fixups.Length);
 606                                 fixups = newf;
 607                         }
 608
 609                         // ECMA 335, Partition III, p94 (7-10)
 610                         //
 611                         // The switch instruction implements a jump table. The format of
 612                         // the instruction is an unsigned int32 representing the number of targets N,
 613                         // followed by N int32 values specifying jump targets: these targets are
 614                         // represented as offsets (positive or negative) from the beginning of the
 615                         // instruction following this switch instruction.
 616                         //
 617                         // We must make sure it gets an offset from the *end* of the last label
 618                         // (eg, the beginning of the instruction following this).
 619                         //
 620                         // remaining is the number of bytes from the current instruction to the
 621                         // instruction that will be emitted.
 622
 623                         for (int i = 0, remaining = count * 4; i < count; ++i, remaining -= 4) {
 624                                 fixups [num_fixups].offset = remaining;
 625                                 fixups [num_fixups].pos = code_len;
 626                                 fixups [num_fixups].label_idx = labels [i].label;
 627                                 num_fixups++;
 628                                 code_len += 4;
 629                         }
 630                 }
 631
 632                 public virtual void Emit (OpCode opcode, LocalBuilder lbuilder)
 633                 {
 634                         uint pos = lbuilder.position;
 635                         bool load_addr = false;
 636                         bool is_store = false;
 637                         make_room (6);
 638
 639                         if (lbuilder.ilgen != this)
 640                                 throw new Exception ("Trying to emit a local from a different ILGenerator.");
 641
 642                         /* inline the code from ll_emit () to optimize il code size */
 643                         if (opcode.StackBehaviourPop == StackBehaviour.Pop1) {
 644                                 cur_stack --;
 645                                 is_store = true;
 646                         } else {
 647                                 cur_stack++;
 648                                 if (cur_stack > max_stack)
 649                                         max_stack = cur_stack;
 650                                 load_addr = opcode.StackBehaviourPush == StackBehaviour.Pushi;
 651                         }
 652                         if (load_addr) {
 653                                 if (pos < 256) {
 654                                         code [code_len++] = (byte)0x12;
 655                                         code [code_len++] = (byte)pos;
 656                                 } else {
 657                                         code [code_len++] = (byte)0xfe;
 658                                         code [code_len++] = (byte)0x0d;
 659                                         code [code_len++] = (byte)(pos & 0xff);
 660                                         code [code_len++] = (byte)((pos >> 8) & 0xff);
 661                                 }
 662                         } else {
 663                                 if (is_store) {
 664                                         if (pos < 4) {
 665                                                 code [code_len++] = (byte)(0x0a + pos);
 666                                         } else if (pos < 256) {
 667                                                 code [code_len++] = (byte)0x13;
 668                                                 code [code_len++] = (byte)pos;
 669                                         } else {
 670                                                 code [code_len++] = (byte)0xfe;
 671                                                 code [code_len++] = (byte)0x0e;
 672                                                 code [code_len++] = (byte)(pos & 0xff);
 673                                                 code [code_len++] = (byte)((pos >> 8) & 0xff);
 674                                         }
 675                                 } else {
 676                                         if (pos < 4) {
 677                                                 code [code_len++] = (byte)(0x06 + pos);
 678                                         } else if (pos < 256) {
 679                                                 code [code_len++] = (byte)0x11;
 680                                                 code [code_len++] = (byte)pos;
 681                                         } else {
 682                                                 code [code_len++] = (byte)0xfe;
 683                                                 code [code_len++] = (byte)0x0c;
 684                                                 code [code_len++] = (byte)(pos & 0xff);
 685                                                 code [code_len++] = (byte)((pos >> 8) & 0xff);
 686                                         }
 687                                 }
 688                         }
 689                 }
 690
 691                 public virtual void Emit (OpCode opcode, MethodInfo method)
 692                 {
 693                         if (method == null)
 694                                 throw new ArgumentNullException ("method");
 695
 696                         int token = token_gen.GetToken (method);
 697                         make_room (6);
 698                         ll_emit (opcode);
 699                         if (method.DeclaringType.Module == module)
 700                                 add_token_fixup (method);
 701                         emit_int (token);
 702                         if (method.ReturnType != void_type)
 703                                 cur_stack ++;
 704
 705                         if (opcode.StackBehaviourPop == StackBehaviour.Varpop)
 706                                 cur_stack -= method.GetParameterCount ();
 707                 }
 708
 709                 private void Emit (OpCode opcode, MethodInfo method, int token)
 710                 {
 711                         make_room (6);
 712                         ll_emit (opcode);
 713                         if (method.DeclaringType.Module == module)
 714                                 add_token_fixup (method);
 715                         emit_int (token);
 716                         if (method.ReturnType != void_type)
 717                                 cur_stack ++;
 718
 719                         if (opcode.StackBehaviourPop == StackBehaviour.Varpop)
 720                                 cur_stack -= method.GetParameterCount ();
 721                 }
 722
 723                 [CLSCompliant(false)]
 724                 public void Emit (OpCode opcode, sbyte val)
 725                 {
 726                         make_room (3);
 727                         ll_emit (opcode);
 728                         code [code_len++] = (byte)val;
 729                 }
 730
 731                 public virtual void Emit (OpCode opcode, SignatureHelper shelper)
 732                 {
 733                         int token = token_gen.GetToken (shelper);
 734                         make_room (6);
 735                         ll_emit (opcode);
 736                         emit_int (token);
 737                 }
 738
 739                 public virtual void Emit (OpCode opcode, float val)
 740                 {
 741                         byte[] s = System.BitConverter.GetBytes (val);
 742                         make_room (6);
 743                         ll_emit (opcode);
 744                         if (BitConverter.IsLittleEndian){
 745                                 System.Array.Copy (s, 0, code, code_len, 4);
 746                                 code_len += 4;
 747                         } else {
 748                                 code [code_len++] = s [3];
 749                                 code [code_len++] = s [2];
 750                                 code [code_len++] = s [1];
 751                                 code [code_len++] = s [0];
 752                         }
 753                 }
 754
 755                 public virtual void Emit (OpCode opcode, string val)
 756                 {
 757                         int token = token_gen.GetToken (val);
 758                         make_room (6);
 759                         ll_emit (opcode);
 760                         emit_int (token);
 761                 }
 762
 763                 public virtual void Emit (OpCode opcode, Type type)
 764                 {
 765                         make_room (6);
 766                         ll_emit (opcode);
 767                         emit_int (token_gen.GetToken (type));
 768                 }
 769
 770                 [MonoTODO ("Do something about varargs method")]
 771                 public void EmitCall (OpCode opcode, MethodInfo methodinfo, Type[] optionalParamTypes)
 772                 {
 773                         if (methodinfo == null)
 774                                 throw new ArgumentNullException ("methodinfo can not be null");
 775                         short value = opcode.Value;
 776                         if (!(value == OpCodes.Call.Value || value == OpCodes.Callvirt.Value))
 777                                 throw new NotSupportedException ("Only Call and CallVirt are allowed");
 778                         if (optionalParamTypes != null){
 779                                 if ((methodinfo.CallingConvention & CallingConventions.VarArgs)  == 0){
 780                                         throw new InvalidOperationException ("Method is not VarArgs method and optional types were passed");
 781                                 }
 782
 783                                 int token = token_gen.GetToken (methodinfo, optionalParamTypes);
 784                                 Emit (opcode, methodinfo, token);
 785                                 return;
 786                         }
 787                         Emit (opcode, methodinfo);
 788                 }
 789
 790                 public void EmitCalli (OpCode opcode, CallingConvention unmanagedCallConv, Type returnType, Type[] paramTypes)
 791                 {
 792                         SignatureHelper helper
 793                                 = SignatureHelper.GetMethodSigHelper (module, 0, unmanagedCallConv, returnType, paramTypes);
 794                         Emit (opcode, helper);
 795                 }
 796
 797                 public void EmitCalli (OpCode opcode, CallingConventions callConv, Type returnType, Type[] paramTypes, Type[] optionalParamTypes)
 798                 {
 799                         if (optionalParamTypes != null)
 800                                 throw new NotImplementedException ();
 801
 802                         SignatureHelper helper
 803                                 = SignatureHelper.GetMethodSigHelper (module, callConv, 0, returnType, paramTypes);
 804                         Emit (opcode, helper);
 805                 }
 806
 807                 public virtual void EmitWriteLine (FieldInfo field)
 808                 {
 809                         if (field == null)
 810                                 throw new ArgumentNullException ("field");
 811
 812                         // The MS implementation does not check for valuetypes here but it
 813                         // should. Also, it should check that if the field is not static,
 814                         // then it is a member of this type.
 815                         if (field.IsStatic)
 816                                 Emit (OpCodes.Ldsfld, field);
 817                         else {
 818                                 Emit (OpCodes.Ldarg_0);
 819                                 Emit (OpCodes.Ldfld, field);
 820                         }
 821                         Emit (OpCodes.Call,
 822                               typeof (Console).GetMethod ("WriteLine",
 823                                                           new Type[1] { field.FieldType }));
 824                 }
 825
 826                 public virtual void EmitWriteLine (LocalBuilder lbuilder)
 827                 {
 828                         if (lbuilder == null)
 829                                 throw new ArgumentNullException ("lbuilder");
 830                         if (lbuilder.LocalType is TypeBuilder)
 831                                 throw new  ArgumentException ("Output streams do not support TypeBuilders.");
 832                         // The MS implementation does not check for valuetypes here but it
 833                         // should.
 834                         Emit (OpCodes.Ldloc, lbuilder);
 835                         Emit (OpCodes.Call,
 836                               typeof (Console).GetMethod ("WriteLine",
 837                                                           new Type[1] { lbuilder.LocalType }));
 838                 }
 839
 840                 public virtual void EmitWriteLine (string val)
 841                 {
 842                         Emit (OpCodes.Ldstr, val);
 843                         Emit (OpCodes.Call,
 844                               typeof (Console).GetMethod ("WriteLine",
 845                                                           new Type[1] { typeof(string)}));
 846                 }
 847
 848                 public virtual void EndExceptionBlock ()
 849                 {
 850                         if (open_blocks.Count <= 0)
 851                                 throw new NotSupportedException ("Not in an exception block");
 852                         InternalEndClause ();
 853                         MarkLabel (ex_handlers [cur_block].end);
 854                         ex_handlers [cur_block].End (code_len);
 855                         ex_handlers [cur_block].Debug (cur_block);
 856                         //System.Console.WriteLine ("End Block {0} (handlers: {1})", cur_block, ex_handlers [cur_block].NumHandlers ());
 857                         open_blocks.Pop ();
 858                         if (open_blocks.Count > 0)
 859                                 cur_block = (int)open_blocks.Peek ();
 860                         //Console.WriteLine ("curblock restored to {0}", cur_block);
 861                         //throw new NotImplementedException ();
 862                 }
 863
 864                 public virtual void EndScope ()
 865                 { }
 866
 867                 public virtual void MarkLabel (Label loc)
 868                 {
 869                         if (loc.label < 0 || loc.label >= num_labels)
 870                                 throw new System.ArgumentException ("The label is not valid");
 871                         if (labels [loc.label].addr >= 0)
 872                                 throw new System.ArgumentException ("The label was already defined");
 873                         labels [loc.label].addr = code_len;
 874                         if (labels [loc.label].maxStack > cur_stack)
 875                                 cur_stack = labels [loc.label].maxStack;
 876                 }
 877
 878                 public virtual void MarkSequencePoint (ISymbolDocumentWriter document, int startLine,
 879                                                        int startColumn, int endLine, int endColumn)
 880                 {
 881                         if (currentSequence == null || currentSequence.Document != document) {
 882                                 if (sequencePointLists == null)
 883                                         sequencePointLists = new ArrayList ();
 884                                 currentSequence = new SequencePointList (document);
 885                                 sequencePointLists.Add (currentSequence);
 886                         }
 887
 888                         currentSequence.AddSequencePoint (code_len, startLine, startColumn, endLine, endColumn);
 889                 }
 890
 891                 internal void GenerateDebugInfo (ISymbolWriter symbolWriter)
 892                 {
 893                         if (sequencePointLists != null) {
 894                                 SequencePointList first = (SequencePointList) sequencePointLists [0];
 895                                 SequencePointList last = (SequencePointList) sequencePointLists [sequencePointLists.Count - 1];
 896                                 symbolWriter.SetMethodSourceRange (first.Document, first.StartLine, first.StartColumn, last.Document, last.EndLine, last.EndColumn);
 897
 898                                 foreach (SequencePointList list in sequencePointLists)
 899                                         symbolWriter.DefineSequencePoints (list.Document, list.GetOffsets(), list.GetLines(), list.GetColumns(), list.GetEndLines(), list.GetEndColumns());
 900
 901                                 if (locals != null) {
 902                                         foreach (LocalBuilder local in locals) {
 903                                                 if (local.Name != null && local.Name.Length > 0) {
 904                                                         SignatureHelper sighelper = SignatureHelper.GetLocalVarSigHelper (module);
 905                                                         sighelper.AddArgument (local.LocalType);
 906                                                         byte[] signature = sighelper.GetSignature ();
 907                                                         symbolWriter.DefineLocalVariable (local.Name, FieldAttributes.Public, signature, SymAddressKind.ILOffset, local.position, 0, 0, local.StartOffset, local.EndOffset);
 908                                                 }
 909                                         }
 910                                 }
 911                                 sequencePointLists = null;
 912                         }
 913                 }
 914
 915                 internal bool HasDebugInfo
 916                 {
 917                         get { return sequencePointLists != null; }
 918                 }
 919
 920                 public virtual void ThrowException (Type exceptionType)
 921                 {
 922                         if (exceptionType == null)
 923                                 throw new ArgumentNullException ("exceptionType");
 924                         if (! ((exceptionType == typeof (Exception)) ||
 925                                    exceptionType.IsSubclassOf (typeof (Exception))))
 926                                 throw new ArgumentException ("Type should be an exception type", "exceptionType");
 927                         ConstructorInfo ctor = exceptionType.GetConstructor (new Type[0]);
 928                         if (ctor == null)
 929                                 throw new ArgumentException ("Type should have a default constructor", "exceptionType");
 930                         Emit (OpCodes.Newobj, ctor);
 931                         Emit (OpCodes.Throw);
 932                 }
 933
 934                 [MonoTODO]
 935                 public void UsingNamespace (String usingNamespace)
 936                 {
 937                         throw new NotImplementedException ();
 938                 }
 939
 940                 internal void label_fixup ()
 941                 {
 942                         for (int i = 0; i < num_fixups; ++i) {
 943
 944                                 // Diff is the offset from the end of the jump instruction to the address of the label
 945                                 int diff = labels [fixups [i].label_idx].addr - (fixups [i].pos + fixups [i].offset);
 946                                 if (fixups [i].offset == 1) {
 947                                         code [fixups [i].pos] = (byte)((sbyte) diff);
 948                                 } else {
 949                                         int old_cl = code_len;
 950                                         code_len = fixups [i].pos;
 951                                         emit_int (diff);
 952                                         code_len = old_cl;
 953                                 }
 954                         }
 955                 }
 956
 957                 internal static int Mono_GetCurrentOffset (ILGenerator ig)
 958                 {
 959                         return ig.code_len;
 960                 }
 961
 962                 void _ILGenerator.GetIDsOfNames ([In] ref Guid riid, IntPtr rgszNames, uint cNames, uint lcid, IntPtr rgDispId)
 963                 {
 964                         throw new NotImplementedException ();
 965                 }
 966
 967                 void _ILGenerator.GetTypeInfo (uint iTInfo, uint lcid, IntPtr ppTInfo)
 968                 {
 969                         throw new NotImplementedException ();
 970                 }
 971
 972                 void _ILGenerator.GetTypeInfoCount (out uint pcTInfo)
 973                 {
 974                         throw new NotImplementedException ();
 975                 }
 976
 977                 void _ILGenerator.Invoke (uint dispIdMember, [In] ref Guid riid, uint lcid, short wFlags, IntPtr pDispParams, IntPtr pVarResult, IntPtr pExcepInfo, IntPtr puArgErr)
 978                 {
 979                         throw new NotImplementedException ();
 980                 }
 981         }
 982
 983         internal class SequencePointList
 984         {
 985                 ISymbolDocumentWriter doc;
 986                 SequencePoint[] points;
 987                 int count;
 988                 const int arrayGrow = 10;
 989
 990                 public SequencePointList (ISymbolDocumentWriter doc)
 991                 {
 992                         this.doc = doc;
 993                 }
 994
 995                 public ISymbolDocumentWriter Document {
 996                         get { return doc; }
 997                 }
 998
 999                 public int[] GetOffsets()
1000                 {
1001                         int[] data = new int [count];
1002                         for (int n=0; n<count; n++) data [n] = points[n].Offset;
1003                         return data;
1004                 }
1005                 public int[] GetLines()
1006                 {
1007                         int[] data = new int [count];
1008                         for (int n=0; n<count; n++) data [n] = points[n].Line;
1009                         return data;
1010                 }
1011                 public int[] GetColumns()
1012                 {
1013                         int[] data = new int [count];
1014                         for (int n=0; n<count; n++) data [n] = points[n].Col;
1015                         return data;
1016                 }
1017                 public int[] GetEndLines()
1018                 {
1019                         int[] data = new int [count];
1020                         for (int n=0; n<count; n++) data [n] = points[n].EndLine;
1021                         return data;
1022                 }
1023                 public int[] GetEndColumns()
1024                 {
1025                         int[] data = new int [count];
1026                         for (int n=0; n<count; n++) data [n] = points[n].EndCol;
1027                         return data;
1028                 }
1029                 public int StartLine {
1030                         get { return points[0].Line; }
1031                 }
1032                 public int EndLine {
1033                         get { return points[count - 1].Line; }
1034                 }
1035                 public int StartColumn {
1036                         get { return points[0].Col; }
1037                 }
1038                 public int EndColumn {
1039                         get { return points[count - 1].Col; }
1040                 }
1041
1042                 public void AddSequencePoint (int offset, int line, int col, int endLine, int endCol)
1043                 {
1044                         SequencePoint s = new SequencePoint ();
1045                         s.Offset = offset;
1046                         s.Line = line;
1047                         s.Col = col;
1048                         s.EndLine = endLine;
1049                         s.EndCol = endCol;
1050
1051                         if (points == null) {
1052                                 points = new SequencePoint [arrayGrow];
1053                         } else if (count >= points.Length) {
1054                                 SequencePoint[] temp = new SequencePoint [count + arrayGrow];
1055                                 Array.Copy (points, temp, points.Length);
1056                                 points = temp;
1057                         }
1058
1059                         points [count] = s;
1060                         count++;
1061                 }
1062         }
1063
1064         struct SequencePoint {
1065                 public int Offset;
1066                 public int Line;
1067                 public int Col;
1068                 public int EndLine;
1069                 public int EndCol;
1070         }
1071 }