libcpp/include/line-map.h

   1 /* Map logical line numbers to (source file, line number) pairs.
   2    Copyright (C) 2001, 2003, 2004, 2007, 2008, 2009
   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 3, 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; see the file COPYING3.  If not see
  17 <http://www.gnu.org/licenses/>.
  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 #ifndef LIBCPP_LINE_MAP_H
  24 #define LIBCPP_LINE_MAP_H
  25
  26 #ifdef __cplusplus
  27 extern "C" {
  28 #endif
  29
  30 #ifndef GTY
  31 #define GTY(x) /* nothing */
  32 #endif
  33
  34 /* Reason for adding a line change with add_line_map ().  LC_ENTER is
  35    when including a new file, e.g. a #include directive in C.
  36    LC_LEAVE is when reaching a file's end.  LC_RENAME is when a file
  37    name or line number changes for neither of the above reasons
  38    (e.g. a #line directive in C); LC_RENAME_VERBATIM is like LC_RENAME
  39    but a filename of "" is not specially interpreted as standard input.  */
  40 enum lc_reason {LC_ENTER = 0, LC_LEAVE, LC_RENAME, LC_RENAME_VERBATIM};
  41
  42 /* The type of line numbers.  */
  43 typedef unsigned int linenum_type;
  44
  45 /* A logical line/column number, i.e. an "index" into a line_map.  */
  46 /* Long-term, we want to use this to replace struct location_s (in input.h),
  47    and effectively typedef source_location location_t.  */
  48 typedef unsigned int source_location;
  49
  50 /* Memory allocation function typedef.  Works like xrealloc.  */
  51 typedef void *(*line_map_realloc) (void *, size_t);
  52
  53 /* Physical source file TO_FILE at line TO_LINE at column 0 is represented
  54    by the logical START_LOCATION.  TO_LINE+L at column C is represented by
  55    START_LOCATION+(L*(1<<column_bits))+C, as long as C<(1<<column_bits),
  56    and the result_location is less than the next line_map's start_location.
  57    (The top line is line 1 and the leftmost column is column 1; line/column 0
  58    means "entire file/line" or "unknown line/column" or "not applicable".)
  59    INCLUDED_FROM is an index into the set that gives the line mapping
  60    at whose end the current one was included.  File(s) at the bottom
  61    of the include stack have this set to -1.  REASON is the reason for
  62    creation of this line map, SYSP is one for a system header, two for
  63    a C system header file that therefore needs to be extern "C"
  64    protected in C++, and zero otherwise.  */
  65 struct GTY(()) line_map {
  66   const char *to_file;
  67   linenum_type to_line;
  68   source_location start_location;
  69   int included_from;
  70   ENUM_BITFIELD (lc_reason) reason : CHAR_BIT;
  71   /* The sysp field isn't really needed now that it's in cpp_buffer.  */
  72   unsigned char sysp;
  73   /* Number of the low-order source_location bits used for a column number.  */
  74   unsigned int column_bits : 8;
  75 };
  76
  77 /* A set of chronological line_map structures.  */
  78 struct GTY(()) line_maps {
  79   struct line_map * GTY ((length ("%h.used"))) maps;
  80   unsigned int allocated;
  81   unsigned int used;
  82
  83   unsigned int cache;
  84
  85   /* The most recently listed include stack, if any, starts with
  86      LAST_LISTED as the topmost including file.  -1 indicates nothing
  87      has been listed yet.  */
  88   int last_listed;
  89
  90   /* Depth of the include stack, including the current file.  */
  91   unsigned int depth;
  92
  93   /* If true, prints an include trace a la -H.  */
  94   bool trace_includes;
  95
  96   /* Highest source_location "given out".  */
  97   source_location highest_location;
  98
  99   /* Start of line of highest source_location "given out".  */
 100   source_location highest_line;
 101
 102   /* The maximum column number we can quickly allocate.  Higher numbers
 103      may require allocating a new line_map.  */
 104   unsigned int max_column_hint;
 105
 106   /* If non-null, the allocator to use when resizing 'maps'.  If null,
 107      xrealloc is used.  */
 108   line_map_realloc reallocator;
 109 };
 110
 111 /* Initialize a line map set.  */
 112 extern void linemap_init (struct line_maps *);
 113
 114 /* Free a line map set.  */
 115 extern void linemap_free (struct line_maps *);
 116
 117 /* Check for and warn about line_maps entered but not exited.  */
 118
 119 extern void linemap_check_files_exited (struct line_maps *);
 120
 121 /* Return a source_location for the start (i.e. column==0) of
 122    (physical) line TO_LINE in the current source file (as in the
 123    most recent linemap_add).   MAX_COLUMN_HINT is the highest column
 124    number we expect to use in this line (but it does not change
 125    the highest_location).  */
 126
 127 extern source_location linemap_line_start
 128 (struct line_maps *set, linenum_type to_line,  unsigned int max_column_hint);
 129
 130 /* Add a mapping of logical source line to physical source file and
 131    line number.
 132
 133    The text pointed to by TO_FILE must have a lifetime
 134    at least as long as the final call to lookup_line ().  An empty
 135    TO_FILE means standard input.  If reason is LC_LEAVE, and
 136    TO_FILE is NULL, then TO_FILE, TO_LINE and SYSP are given their
 137    natural values considering the file we are returning to.
 138
 139    A call to this function can relocate the previous set of
 140    maps, so any stored line_map pointers should not be used.  */
 141 extern const struct line_map *linemap_add
 142   (struct line_maps *, enum lc_reason, unsigned int sysp,
 143    const char *to_file, linenum_type to_line);
 144
 145 /* Given a logical line, returns the map from which the corresponding
 146    (source file, line) pair can be deduced.  */
 147 extern const struct line_map *linemap_lookup
 148   (struct line_maps *, source_location);
 149
 150 /* Converts a map and a source_location to source line.  */
 151 #define SOURCE_LINE(MAP, LOC) \
 152   ((((LOC) - (MAP)->start_location) >> (MAP)->column_bits) + (MAP)->to_line)
 153
 154 #define SOURCE_COLUMN(MAP, LOC) \
 155   (((LOC) - (MAP)->start_location) & ((1 << (MAP)->column_bits) - 1))
 156
 157 /* Returns the last source line within a map.  This is the (last) line
 158    of the #include, or other directive, that caused a map change.  */
 159 #define LAST_SOURCE_LINE(MAP) \
 160   SOURCE_LINE (MAP, LAST_SOURCE_LINE_LOCATION (MAP))
 161 #define LAST_SOURCE_LINE_LOCATION(MAP) \
 162   ((((MAP)[1].start_location - 1 - (MAP)->start_location) \
 163     & ~((1 << (MAP)->column_bits) - 1))                   \
 164    + (MAP)->start_location)
 165
 166 /* Returns the map a given map was included from.  */
 167 #define INCLUDED_FROM(SET, MAP) (&(SET)->maps[(MAP)->included_from])
 168
 169 /* Nonzero if the map is at the bottom of the include stack.  */
 170 #define MAIN_FILE_P(MAP) ((MAP)->included_from < 0)
 171
 172 /* Set LOC to a source position that is the same line as the most recent
 173    linemap_line_start, but with the specified TO_COLUMN column number.  */
 174
 175 #define LINEMAP_POSITION_FOR_COLUMN(LOC, SET, TO_COLUMN) do { \
 176   unsigned int to_column = (TO_COLUMN); \
 177   struct line_maps *set = (SET); \
 178   if (__builtin_expect (to_column >= set->max_column_hint, 0)) \
 179     (LOC) = linemap_position_for_column (set, to_column); \
 180   else { \
 181     source_location r = set->highest_line; \
 182     r = r + to_column; \
 183     if (r >= set->highest_location) \
 184       set->highest_location = r; \
 185     (LOC) = r;                   \
 186   }} while (0)
 187
 188
 189 extern source_location
 190 linemap_position_for_column (struct line_maps *set, unsigned int to_column);
 191
 192 #ifdef __cplusplus
 193 }
 194 #endif
 195
 196 #endif /* !LIBCPP_LINE_MAP_H  */