mcs/mcs/location.cs

   1 //
   2 // location.cs: Keeps track of the location of source code entity
   3 //
   4 // Author:
   5 //   Miguel de Icaza
   6 //   Atsushi Enomoto  <atsushi@ximian.com>
   7 //   Marek Safar (marek.safar@gmail.com)
   8 //
   9 // Copyright 2001 Ximian, Inc.
  10 // Copyright 2005 Novell, Inc.
  11 //
  12
  13 using System;
  14 using System.Collections.Generic;
  15 using Mono.CompilerServices.SymbolWriter;
  16 using System.Diagnostics;
  17 using System.Linq;
  18
  19 namespace Mono.CSharp
  20 {
  21         //
  22         //  This is one single source file.
  23         //
  24         public class SourceFile : IEquatable<SourceFile>
  25         {
  26                 //
  27                 // Used by #line directive to track hidden sequence point
  28                 // regions
  29                 //
  30                 struct LocationRegion : IComparable<LocationRegion>
  31                 {
  32                         public readonly Location Start;
  33                         public readonly Location End;
  34
  35                         public LocationRegion (Location start, Location end)
  36                         {
  37                                 this.Start = start;
  38                                 this.End = end;
  39                         }
  40
  41                         public int CompareTo (LocationRegion other)
  42                         {
  43                                 if (Start.Row == other.Start.Row)
  44                                         return Start.Column.CompareTo (other.Start.Column);
  45
  46                                 return Start.Row.CompareTo (other.Start.Row);
  47                         }
  48
  49                         public override string ToString ()
  50                         {
  51                                 return Start.ToString () + " - " + End.ToString ();
  52                         }
  53                 }
  54
  55                 static readonly byte[] MD5Algorith = { 96, 166, 110, 64, 207, 100, 130, 76, 182, 240, 66, 212, 129, 114, 167, 153 };
  56
  57                 public readonly string Name;
  58                 public readonly string FullPathName;
  59                 public readonly int Index;
  60                 public bool AutoGenerated;
  61
  62                 SourceFileEntry file;
  63                 byte[] algGuid, checksum;
  64                 List<LocationRegion> hidden_lines;
  65
  66                 public SourceFile (string name, string path, int index)
  67                 {
  68                         this.Index = index;
  69                         this.Name = name;
  70                         this.FullPathName = path;
  71                 }
  72
  73                 public byte[] Checksum {
  74                         get {
  75                                 return checksum;
  76                         }
  77                 }
  78
  79                 public bool HasChecksum {
  80                         get {
  81                                 return checksum != null;
  82                         }
  83                 }
  84
  85                 public SourceFileEntry SourceFileEntry {
  86                         get {
  87                                 return file;
  88                         }
  89                 }
  90
  91                 public void SetChecksum (byte[] checksum)
  92                 {
  93                         SetChecksum (MD5Algorith, checksum);
  94                 }
  95
  96                 public void SetChecksum (byte[] algorithmGuid, byte[] checksum)
  97                 {
  98                         this.algGuid = algorithmGuid;
  99                         this.checksum = checksum;
 100                 }
 101
 102                 public SourceFileEntry CreateSymbolInfo (MonoSymbolFile symwriter)
 103                 {
 104                         if (hidden_lines != null)
 105                                 hidden_lines.Sort ();
 106
 107                         file = new SourceFileEntry (symwriter, FullPathName, algGuid, checksum);
 108                         if (AutoGenerated)
 109                                 file.SetAutoGenerated ();
 110
 111                         return file;
 112                 }
 113
 114                 public bool Equals (SourceFile other)
 115                 {
 116                         return FullPathName == other.FullPathName;
 117                 }
 118
 119                 public bool IsHiddenLocation (Location loc)
 120                 {
 121                         if (hidden_lines == null)
 122                                 return false;
 123
 124                         int index = hidden_lines.BinarySearch (new LocationRegion (loc, loc));
 125                         index = ~index;
 126                         if (index > 0) {
 127                                 var found = hidden_lines[index - 1];
 128                                 if (loc.Row < found.End.Row)
 129                                         return true;
 130                         }
 131
 132                         return false;
 133                 }
 134
 135                 public void RegisterHiddenScope (Location start, Location end)
 136                 {
 137                         if (hidden_lines == null)
 138                                 hidden_lines = new List<LocationRegion> ();
 139
 140                         hidden_lines.Add (new LocationRegion (start, end));
 141                 }
 142
 143                 public override string ToString ()
 144                 {
 145                         return String.Format ("SourceFile ({0}:{1}:{2})", Name, FullPathName, Index);
 146                 }
 147         }
 148
 149         /// <summary>
 150         ///   Keeps track of the location in the program
 151         /// </summary>
 152         ///
 153         /// <remarks>
 154         ///   This uses a compact representation and a couple of auxiliary
 155         ///   structures to keep track of tokens to (file,line and column)
 156         ///   mappings. The usage of the bits is:
 157         ///
 158         ///     - 16 bits for "checkpoint" which is a mixed concept of
 159         ///       file and "line segment"
 160         ///     - 8 bits for line delta (offset) from the line segment
 161         ///     - 8 bits for column number.
 162         ///
 163         ///   http://lists.ximian.com/pipermail/mono-devel-list/2004-December/009508.html
 164         /// </remarks>
 165         public struct Location : IEquatable<Location>
 166         {
 167                 struct Checkpoint {
 168                         public readonly int LineOffset;
 169                         public readonly int File;
 170
 171                         public Checkpoint (int file, int line)
 172                         {
 173                                 File = file;
 174                                 LineOffset = line - (int) (line % (1 << line_delta_bits));
 175                         }
 176                 }
 177
 178 #if FULL_AST
 179                 readonly long token;
 180
 181                 const int column_bits = 24;
 182                 const int line_delta_bits = 24;
 183 #else
 184                 readonly int token;
 185
 186                 const int column_bits = 8;
 187                 const int line_delta_bits = 8;
 188 #endif
 189                 const int checkpoint_bits = 16;
 190
 191                 const int column_mask = (1 << column_bits) - 1;
 192                 const int max_column = column_mask;
 193
 194                 static List<SourceFile> source_list;
 195                 static int current_source;
 196                 static Checkpoint [] checkpoints;
 197                 static int checkpoint_index;
 198
 199                 public readonly static Location Null = new Location ();
 200                 public static bool InEmacs;
 201
 202                 static Location ()
 203                 {
 204                         Reset ();
 205                 }
 206
 207                 public static void Reset ()
 208                 {
 209                         source_list = new List<SourceFile> ();
 210                         current_source = 0;
 211                         checkpoint_index = 0;
 212                 }
 213
 214                 public static void AddFile (SourceFile file)
 215                 {
 216                         source_list.Add (file);
 217                 }
 218
 219                 // <summary>
 220                 //   After adding all source files we want to compile with AddFile(), this method
 221                 //   must be called to `reserve' an appropriate number of bits in the token for the
 222                 //   source file.  We reserve some extra space for files we encounter via #line
 223                 //   directives while parsing.
 224                 // </summary>
 225                 static public void Initialize (List<SourceFile> files)
 226                 {
 227 #if NET_4_0 || MONODROID
 228                         source_list.AddRange (files);
 229 #else
 230                         source_list.AddRange (files.ToArray ());
 231 #endif
 232
 233                         checkpoints = new Checkpoint [System.Math.Max (1, source_list.Count * 2)];
 234                         if (checkpoints.Length > 0)
 235                                 checkpoints [0] = new Checkpoint (0, 0);
 236                 }
 237
 238                 static public void Push (SourceFile file)
 239                 {
 240                         current_source = file != null ? file.Index : -1;
 241                         // File is always pushed before being changed.
 242                 }
 243
 244                 public Location (int row, int column)
 245                 {
 246                         if (row <= 0)
 247                                 token = 0;
 248                         else {
 249                                 if (column > max_column)
 250                                         column = max_column;
 251
 252                                 long target = -1;
 253                                 long delta = 0;
 254
 255                                 // FIXME: This value is certainly wrong but what was the intension
 256                                 int max = checkpoint_index < 10 ?
 257                                         checkpoint_index : 10;
 258                                 for (int i = 0; i < max; i++) {
 259                                         int offset = checkpoints [checkpoint_index - i].LineOffset;
 260                                         delta = row - offset;
 261                                         if (delta >= 0 &&
 262                                                 delta < (1 << line_delta_bits) &&
 263                                                 checkpoints [checkpoint_index - i].File == current_source) {
 264                                                 target = checkpoint_index - i;
 265                                                 break;
 266                                         }
 267                                 }
 268                                 if (target == -1) {
 269                                         AddCheckpoint (current_source, row);
 270                                         target = checkpoint_index;
 271                                         delta = row % (1 << line_delta_bits);
 272                                 }
 273
 274                                 long l = column +
 275                                         (delta << column_bits) +
 276                                         (target << (line_delta_bits + column_bits));
 277 #if FULL_AST
 278                                 token = l;
 279 #else
 280                                 token = l > 0xFFFFFFFF ? 0 : (int) l;
 281 #endif
 282                         }
 283                 }
 284
 285                 public static Location operator - (Location loc, int columns)
 286                 {
 287                         return new Location (loc.Row, loc.Column - columns);
 288                 }
 289
 290                 static void AddCheckpoint (int file, int row)
 291                 {
 292                         if (checkpoints.Length == ++checkpoint_index) {
 293                                 Array.Resize (ref checkpoints, checkpoint_index * 2);
 294                         }
 295                         checkpoints [checkpoint_index] = new Checkpoint (file, row);
 296                 }
 297
 298                 string FormatLocation (string fileName)
 299                 {
 300                         if (column_bits == 0 || InEmacs)
 301                                 return fileName + "(" + Row.ToString () + "):";
 302
 303                         return fileName + "(" + Row.ToString () + "," + Column.ToString () +
 304                                 (Column == max_column ? "+):" : "):");
 305                 }
 306
 307                 public override string ToString ()
 308                 {
 309                         return FormatLocation (Name);
 310                 }
 311
 312                 public string ToStringFullName ()
 313                 {
 314                         return FormatLocation (NameFullPath);
 315                 }
 316
 317                 /// <summary>
 318                 ///   Whether the Location is Null
 319                 /// </summary>
 320                 public bool IsNull {
 321                         get { return token == 0; }
 322                 }
 323
 324                 public string Name {
 325                         get {
 326                                 int index = File;
 327                                 if (token == 0 || index <= 0)
 328                                         return null;
 329
 330                                 SourceFile file = source_list [index - 1];
 331                                 return file.Name;
 332                         }
 333                 }
 334
 335                 public string NameFullPath {
 336                         get {
 337                                 int index = File;
 338                                 if (token == 0 || index <= 0)
 339                                         return null;
 340
 341                                 return source_list[index - 1].FullPathName;
 342                         }
 343                 }
 344
 345                 int CheckpointIndex {
 346                         get {
 347                                 const int checkpoint_mask = (1 << checkpoint_bits) - 1;
 348                                 return ((int) (token >> (line_delta_bits + column_bits))) & checkpoint_mask;
 349                         }
 350                 }
 351
 352                 public int Row {
 353                         get {
 354                                 if (token == 0)
 355                                         return 1;
 356
 357                                 int offset = checkpoints[CheckpointIndex].LineOffset;
 358
 359                                 const int line_delta_mask = (1 << column_bits) - 1;
 360                                 return offset + (((int)(token >> column_bits)) & line_delta_mask);
 361                         }
 362                 }
 363
 364                 public int Column {
 365                         get {
 366                                 if (token == 0)
 367                                         return 1;
 368                                 return (int) (token & column_mask);
 369                         }
 370                 }
 371
 372                 public int File {
 373                         get {
 374                                 if (token == 0)
 375                                         return 0;
 376 if (checkpoints.Length <= CheckpointIndex) throw new Exception (String.Format ("Should not happen. Token is {0:X04}, checkpoints are {1}, index is {2}", token, checkpoints.Length, CheckpointIndex));
 377                                 return checkpoints [CheckpointIndex].File;
 378                         }
 379                 }
 380
 381                 // The ISymbolDocumentWriter interface is used by the symbol writer to
 382                 // describe a single source file - for each source file there's exactly
 383                 // one corresponding ISymbolDocumentWriter instance.
 384                 //
 385                 // This class has an internal hash table mapping source document names
 386                 // to such ISymbolDocumentWriter instances - so there's exactly one
 387                 // instance per document.
 388                 //
 389                 // This property returns the ISymbolDocumentWriter instance which belongs
 390                 // to the location's source file.
 391                 //
 392                 // If we don't have a symbol writer, this property is always null.
 393                 public SourceFile SourceFile {
 394                         get {
 395                                 int index = File;
 396                                 if (index == 0)
 397                                         return null;
 398                                 return source_list [index - 1];
 399                         }
 400                 }
 401
 402                 #region IEquatable<Location> Members
 403
 404                 public bool Equals (Location other)
 405                 {
 406                         return this.token == other.token;
 407                 }
 408
 409                 #endregion
 410         }
 411
 412         //
 413         // A bag of additional locations to support full ast tree
 414         //
 415         public class LocationsBag
 416         {
 417                 public class MemberLocations
 418                 {
 419                         public readonly IList<Tuple<Modifiers, Location>> Modifiers;
 420                         Location[] locations;
 421
 422                         public MemberLocations (IList<Tuple<Modifiers, Location>> mods, Location[] locs)
 423                         {
 424                                 Modifiers = mods;
 425                                 locations = locs;
 426                         }
 427
 428                         #region Properties
 429
 430                         public Location this [int index] {
 431                                 get {
 432                                         return locations [index];
 433                                 }
 434                         }
 435
 436                         public int Count {
 437                                 get {
 438                                         return locations.Length;
 439                                 }
 440                         }
 441
 442                         #endregion
 443
 444                         public void AddLocations (params Location[] additional)
 445                         {
 446                                 if (locations == null) {
 447                                         locations = additional;
 448                                 } else {
 449                                         int pos = locations.Length;
 450                                         Array.Resize (ref locations, pos + additional.Length);
 451                                         additional.CopyTo (locations, pos);
 452                                 }
 453                         }
 454                 }
 455
 456                 Dictionary<object, Location[]> simple_locs = new Dictionary<object, Location[]> (ReferenceEquality<object>.Default);
 457                 Dictionary<MemberCore, MemberLocations> member_locs = new Dictionary<MemberCore, MemberLocations> (ReferenceEquality<MemberCore>.Default);
 458
 459                 [Conditional ("FULL_AST")]
 460                 public void AddLocation (object element, params Location[] locations)
 461                 {
 462                         simple_locs.Add (element, locations);
 463                 }
 464
 465                 [Conditional ("FULL_AST")]
 466                 public void AddStatement (object element, params Location[] locations)
 467                 {
 468                         if (locations.Length == 0)
 469                                 throw new ArgumentException ("Statement is missing semicolon location");
 470
 471                         simple_locs.Add (element, locations);
 472                 }
 473
 474                 [Conditional ("FULL_AST")]
 475                 public void AddMember (MemberCore member, IList<Tuple<Modifiers, Location>> modLocations, params Location[] locations)
 476                 {
 477                         member_locs.Add (member, new MemberLocations (modLocations, locations));
 478                 }
 479
 480                 [Conditional ("FULL_AST")]
 481                 public void AppendTo (object existing, params Location[] locations)
 482                 {
 483                         Location[] locs;
 484                         if (simple_locs.TryGetValue (existing, out locs)) {
 485                                 simple_locs [existing] = locs.Concat (locations).ToArray ();
 486                                 return;
 487                         }
 488                 }
 489
 490                 [Conditional ("FULL_AST")]
 491                 public void AppendToMember (MemberCore existing, params Location[] locations)
 492                 {
 493                         MemberLocations member;
 494                         if (member_locs.TryGetValue (existing, out member)) {
 495                                 member.AddLocations (locations);
 496                                 return;
 497                         }
 498                 }
 499
 500                 public Location[] GetLocations (object element)
 501                 {
 502                         Location[] found;
 503                         simple_locs.TryGetValue (element, out found);
 504                         return found;
 505                 }
 506
 507                 public MemberLocations GetMemberLocation (MemberCore element)
 508                 {
 509                         MemberLocations found;
 510                         member_locs.TryGetValue (element, out found);
 511                         return found;
 512                 }
 513         }
 514 }