gcc/line-map.c

   1 /* Map logical line numbers to (source file, line number) pairs.
   2    Copyright (C) 2001, 2003, 2004
   3    Free Software Foundation, Inc.
   4
   5 This program is free software; you can redistribute it and/or modify it
   6 under the terms of the GNU General Public License as published by the
   7 Free Software Foundation; either version 2, or (at your option) any
   8 later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with this program; if not, write to the Free Software
  17 Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  18
  19  In other words, you are welcome to use, share and improve this program.
  20  You are forbidden to forbid anyone else to use, share and improve
  21  what you give them.   Help stamp out software-hoarding!  */
  22
  23 #include "config.h"
  24 #include "system.h"
  25 #include "line-map.h"
  26 #include "intl.h"
  27
  28 static void trace_include (const struct line_maps *, const struct line_map *);
  29
  30 /* Initialize a line map set.  */
  31
  32 void
  33 linemap_init (struct line_maps *set)
  34 {
  35   set->maps = NULL;
  36   set->allocated = 0;
  37   set->used = 0;
  38   set->last_listed = -1;
  39   set->trace_includes = false;
  40   set->depth = 0;
  41   set->cache = 0;
  42   set->highest_location = 0;
  43   set->max_column_hint = 0;
  44 }
  45
  46 /* Check for and warn about line_maps entered but not exited.  */
  47
  48 void
  49 linemap_check_files_exited (struct line_maps *set)
  50 {
  51   struct line_map *map;
  52   /* Depending upon whether we are handling preprocessed input or
  53      not, this can be a user error or an ICE.  */
  54   for (map = &set->maps[set->used - 1]; ! MAIN_FILE_P (map);
  55        map = INCLUDED_FROM (set, map))
  56     fprintf (stderr, "line-map.c: file \"%s\" entered but not left\n",
  57              map->to_file);
  58 }
  59
  60 /* Free a line map set.  */
  61
  62 void
  63 linemap_free (struct line_maps *set)
  64 {
  65   if (set->maps)
  66     {
  67       linemap_check_files_exited (set);
  68
  69       free (set->maps);
  70     }
  71 }
  72
  73 /* Add a mapping of logical source line to physical source file and
  74    line number.
  75
  76    The text pointed to by TO_FILE must have a lifetime
  77    at least as long as the final call to lookup_line ().  An empty
  78    TO_FILE means standard input.  If reason is LC_LEAVE, and
  79    TO_FILE is NULL, then TO_FILE, TO_LINE and SYSP are given their
  80    natural values considering the file we are returning to.
  81
  82    FROM_LINE should be monotonic increasing across calls to this
  83    function.  A call to this function can relocate the previous set of
  84    A call to this function can relocate the previous set of
  85    maps, so any stored line_map pointers should not be used.  */
  86
  87 const struct line_map *
  88 linemap_add (struct line_maps *set, enum lc_reason reason,
  89              unsigned int sysp, const char *to_file, unsigned int to_line)
  90 {
  91   struct line_map *map;
  92   source_location start_location = set->highest_location + 1;
  93
  94   if (set->used && start_location < set->maps[set->used - 1].start_location)
  95     abort ();
  96
  97   if (set->used == set->allocated)
  98     {
  99       set->allocated = 2 * set->allocated + 256;
 100       set->maps = xrealloc (set->maps, set->allocated * sizeof (struct line_map));
 101     }
 102
 103   map = &set->maps[set->used];
 104
 105   if (to_file && *to_file == '\0')
 106     to_file = "<stdin>";
 107
 108   /* If we don't keep our line maps consistent, we can easily
 109      segfault.  Don't rely on the client to do it for us.  */
 110   if (set->depth == 0)
 111     reason = LC_ENTER;
 112   else if (reason == LC_LEAVE)
 113     {
 114       struct line_map *from;
 115       bool error;
 116
 117       if (MAIN_FILE_P (map - 1))
 118         {
 119           if (to_file == NULL)
 120             {
 121               set->depth--;
 122               return NULL;
 123             }
 124           error = true;
 125           reason = LC_RENAME;
 126           from = map - 1;
 127         }
 128       else
 129         {
 130           from = INCLUDED_FROM (set, map - 1);
 131           error = to_file && strcmp (from->to_file, to_file);
 132         }
 133
 134       /* Depending upon whether we are handling preprocessed input or
 135          not, this can be a user error or an ICE.  */
 136       if (error)
 137         fprintf (stderr, "line-map.c: file \"%s\" left but not entered\n",
 138                  to_file);
 139
 140       /* A TO_FILE of NULL is special - we use the natural values.  */
 141       if (error || to_file == NULL)
 142         {
 143           to_file = from->to_file;
 144           to_line = SOURCE_LINE (from, from[1].start_location);
 145           sysp = from->sysp;
 146         }
 147     }
 148
 149   map->reason = reason;
 150   map->sysp = sysp;
 151   map->start_location = start_location;
 152   map->to_file = to_file;
 153   map->to_line = to_line;
 154   set->cache = set->used++;
 155   map->column_bits = 0;
 156   set->highest_location = start_location;
 157   set->max_column_hint = 0;
 158
 159   if (reason == LC_ENTER)
 160     {
 161       map->included_from = set->depth == 0 ? -1 : (int) (set->used - 2);
 162       set->depth++;
 163       if (set->trace_includes)
 164         trace_include (set, map);
 165     }
 166   else if (reason == LC_RENAME)
 167     map->included_from = map[-1].included_from;
 168   else if (reason == LC_LEAVE)
 169     {
 170       set->depth--;
 171       map->included_from = INCLUDED_FROM (set, map - 1)->included_from;
 172     }
 173
 174   return map;
 175 }
 176
 177 source_location
 178 linemap_line_start (struct line_maps *set, unsigned int to_line,
 179                     unsigned int max_column_hint)
 180 {
 181   struct line_map *map = &set->maps[set->used - 1];
 182   source_location highest = set->highest_location;
 183   source_location r;
 184   unsigned int last_line = SOURCE_LINE (map, highest);
 185   int line_delta = to_line - last_line;
 186   bool add_map = false;
 187   if (line_delta < 0
 188       || (line_delta > 10 && line_delta * map->column_bits > 1000)
 189       || (max_column_hint >= (1U << map->column_bits))
 190       || (max_column_hint <= 80 && map->column_bits >= 10))
 191     {
 192       add_map = true;
 193     }
 194   else
 195     max_column_hint = set->max_column_hint;
 196   if (add_map)
 197     {
 198       int column_bits;
 199       if (max_column_hint > 1000000 || highest > 0xC0000000)
 200         {
 201           max_column_hint = 0;
 202           if (highest >0xF0000000)
 203             return 0;
 204           column_bits = 0;
 205         }
 206       else
 207         {
 208           column_bits = 7;
 209           while (max_column_hint >= (1U << column_bits))
 210             column_bits++;
 211           max_column_hint = 1U << column_bits;
 212         }
 213       if (line_delta < 0
 214           || last_line != map->to_line
 215           || SOURCE_COLUMN (map, highest) >= (1U << column_bits))
 216         map = (struct line_map*) linemap_add (set, LC_RENAME, map->sysp,
 217                                       map->to_file, to_line);
 218       map->column_bits = column_bits;
 219       r = map->start_location;
 220     }
 221   else
 222     r = highest - SOURCE_COLUMN (map, highest)
 223       + (line_delta << map->column_bits);
 224   if (r > set->highest_location)
 225     set->highest_location = r;
 226   set->max_column_hint = max_column_hint;
 227   return r;
 228 }
 229
 230 /* Given a logical line, returns the map from which the corresponding
 231    (source file, line) pair can be deduced.  Since the set is built
 232    chronologically, the logical lines are monotonic increasing, and so
 233    the list is sorted and we can use a binary search.  */
 234
 235 const struct line_map *
 236 linemap_lookup (struct line_maps *set, source_location line)
 237 {
 238   unsigned int md, mn, mx;
 239   const struct line_map *cached;
 240
 241   mn = set->cache;
 242   mx = set->used;
 243
 244   cached = &set->maps[mn];
 245   /* We should get a segfault if no line_maps have been added yet.  */
 246   if (line >= cached->start_location)
 247     {
 248       if (mn + 1 == mx || line < cached[1].start_location)
 249         return cached;
 250     }
 251   else
 252     {
 253       mx = mn;
 254       mn = 0;
 255     }
 256
 257   while (mx - mn > 1)
 258     {
 259       md = (mn + mx) / 2;
 260       if (set->maps[md].start_location > line)
 261         mx = md;
 262       else
 263         mn = md;
 264     }
 265
 266   set->cache = mn;
 267   return &set->maps[mn];
 268 }
 269
 270 /* Print the file names and line numbers of the #include commands
 271    which led to the map MAP, if any, to stderr.  Nothing is output if
 272    the most recently listed stack is the same as the current one.  */
 273
 274 void
 275 linemap_print_containing_files (struct line_maps *set,
 276                                 const struct line_map *map)
 277 {
 278   if (MAIN_FILE_P (map) || set->last_listed == map->included_from)
 279     return;
 280
 281   set->last_listed = map->included_from;
 282   map = INCLUDED_FROM (set, map);
 283
 284   fprintf (stderr,  _("In file included from %s:%u"),
 285            map->to_file, LAST_SOURCE_LINE (map));
 286
 287   while (! MAIN_FILE_P (map))
 288     {
 289       map = INCLUDED_FROM (set, map);
 290       /* Translators note: this message is used in conjunction
 291          with "In file included from %s:%ld" and some other
 292          tricks.  We want something like this:
 293
 294          | In file included from sys/select.h:123,
 295          |                  from sys/types.h:234,
 296          |                  from userfile.c:31:
 297          | bits/select.h:45: <error message here>
 298
 299          with all the "from"s lined up.
 300          The trailing comma is at the beginning of this message,
 301          and the trailing colon is not translated.  */
 302       fprintf (stderr, _(",\n                 from %s:%u"),
 303                map->to_file, LAST_SOURCE_LINE (map));
 304     }
 305
 306   fputs (":\n", stderr);
 307 }
 308
 309 /* Print an include trace, for e.g. the -H option of the preprocessor.  */
 310
 311 static void
 312 trace_include (const struct line_maps *set, const struct line_map *map)
 313 {
 314   unsigned int i = set->depth;
 315
 316   while (--i)
 317     putc ('.', stderr);
 318   fprintf (stderr, " %s\n", map->to_file);
 319 }