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