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