gcc/input.h

   1 /* Declarations for variables relating to reading the source file.
   2    Used by parsers, lexical analyzers, and error message routines.
   3    Copyright (C) 1993-2023 Free Software Foundation, Inc.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 3, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.  */
  20
  21 #ifndef GCC_INPUT_H
  22 #define GCC_INPUT_H
  23
  24 #include "line-map.h"
  25
  26 extern GTY(()) class line_maps *line_table;
  27 extern GTY(()) class line_maps *saved_line_table;
  28
  29 /* A value which will never be used to represent a real location.  */
  30 #define UNKNOWN_LOCATION ((location_t) 0)
  31
  32 /* The location for declarations in "<built-in>" */
  33 #define BUILTINS_LOCATION ((location_t) 1)
  34
  35 /* Returns the translated string referring to the special location.  */
  36 const char *special_fname_builtin ();
  37
  38 /* line-map.cc reserves RESERVED_LOCATION_COUNT to the user.  Ensure
  39    both UNKNOWN_LOCATION and BUILTINS_LOCATION fit into that.  */
  40 STATIC_ASSERT (BUILTINS_LOCATION < RESERVED_LOCATION_COUNT);
  41
  42 /* Hasher for 'location_t' values satisfying '!RESERVED_LOCATION_P', thus able
  43    to use 'UNKNOWN_LOCATION'/'BUILTINS_LOCATION' as spare values for
  44    'Empty'/'Deleted'.  */
  45 /* Per PR103157 "'gengtype': 'typedef' causing infinite-recursion code to be
  46    generated", don't use
  47        typedef int_hash<location_t, UNKNOWN_LOCATION, BUILTINS_LOCATION>
  48          location_hash;
  49    here.
  50
  51    It works for a single-use case, but when using a 'struct'-based variant
  52        struct location_hash
  53          : int_hash<location_t, UNKNOWN_LOCATION, BUILTINS_LOCATION> {};
  54    in more than one place, 'gengtype' generates duplicate functions (thus:
  55    "error: redefinition of 'void gt_ggc_mx(location_hash&)'" etc.).
  56    Attempting to mark that one up with GTY options, we run into a 'gengtype'
  57    "parse error: expected '{', have '<'", which probably falls into category
  58    "understanding of C++ is limited", as documented in 'gcc/doc/gty.texi'.
  59
  60    Thus, use a plain ol' '#define':
  61 */
  62 #define location_hash int_hash<location_t, UNKNOWN_LOCATION, BUILTINS_LOCATION>
  63
  64 extern bool is_location_from_builtin_token (location_t);
  65 extern expanded_location expand_location (location_t);
  66
  67 class cpp_char_column_policy;
  68
  69 extern int
  70 location_compute_display_column (expanded_location exploc,
  71                                  const cpp_char_column_policy &policy);
  72
  73 /* A class capturing the bounds of a buffer, to allow for run-time
  74    bounds-checking in a checked build.  */
  75
  76 class char_span
  77 {
  78  public:
  79   char_span (const char *ptr, size_t n_elts) : m_ptr (ptr), m_n_elts (n_elts) {}
  80
  81   /* Test for a non-NULL pointer.  */
  82   operator bool() const { return m_ptr; }
  83
  84   /* Get length, not including any 0-terminator (which may not be,
  85      in fact, present).  */
  86   size_t length () const { return m_n_elts; }
  87
  88   const char *get_buffer () const { return m_ptr; }
  89
  90   char operator[] (int idx) const
  91   {
  92     gcc_assert (idx >= 0);
  93     gcc_assert ((size_t)idx < m_n_elts);
  94     return m_ptr[idx];
  95   }
  96
  97   char_span subspan (int offset, int n_elts) const
  98   {
  99     gcc_assert (offset >= 0);
 100     gcc_assert (offset < (int)m_n_elts);
 101     gcc_assert (n_elts >= 0);
 102     gcc_assert (offset + n_elts <= (int)m_n_elts);
 103     return char_span (m_ptr + offset, n_elts);
 104   }
 105
 106   char *xstrdup () const
 107   {
 108     return ::xstrndup (m_ptr, m_n_elts);
 109   }
 110
 111  private:
 112   const char *m_ptr;
 113   size_t m_n_elts;
 114 };
 115
 116 extern char_span location_get_source_line (const char *file_path, int line);
 117 extern char *get_source_text_between (location_t, location_t);
 118 extern char_span get_source_file_content (const char *file_path);
 119
 120 extern bool location_missing_trailing_newline (const char *file_path);
 121
 122 /* Forward decl of slot within file_cache, so that the definition doesn't
 123    need to be in this header.  */
 124 class file_cache_slot;
 125
 126 /* A cache of source files for use when emitting diagnostics
 127    (and in a few places in the C/C++ frontends).
 128
 129    Results are only valid until the next call to the cache, as
 130    slots can be evicted.
 131
 132    Filenames are stored by pointer, and so must outlive the cache
 133    instance.  */
 134
 135 class file_cache
 136 {
 137  public:
 138   file_cache ();
 139   ~file_cache ();
 140
 141   file_cache_slot *lookup_or_add_file (const char *file_path);
 142   void forcibly_evict_file (const char *file_path);
 143
 144   /* See comments in diagnostic.h about the input conversion context.  */
 145   struct input_context
 146   {
 147     diagnostic_input_charset_callback ccb;
 148     bool should_skip_bom;
 149   };
 150   void initialize_input_context (diagnostic_input_charset_callback ccb,
 151                                  bool should_skip_bom);
 152
 153  private:
 154   file_cache_slot *evicted_cache_tab_entry (unsigned *highest_use_count);
 155   file_cache_slot *add_file (const char *file_path);
 156   file_cache_slot *lookup_file (const char *file_path);
 157
 158  private:
 159   static const size_t num_file_slots = 16;
 160   file_cache_slot *m_file_slots;
 161   input_context in_context;
 162 };
 163
 164 extern expanded_location
 165 expand_location_to_spelling_point (location_t,
 166                                    enum location_aspect aspect
 167                                      = LOCATION_ASPECT_CARET);
 168 extern location_t expansion_point_location_if_in_system_header (location_t);
 169 extern location_t expansion_point_location (location_t);
 170
 171 extern location_t input_location;
 172
 173 extern location_t location_with_discriminator (location_t, int);
 174 extern bool has_discriminator (location_t);
 175 extern int get_discriminator_from_loc (location_t);
 176
 177 #define LOCATION_FILE(LOC) ((expand_location (LOC)).file)
 178 #define LOCATION_LINE(LOC) ((expand_location (LOC)).line)
 179 #define LOCATION_COLUMN(LOC)((expand_location (LOC)).column)
 180 #define LOCATION_LOCUS(LOC) \
 181   ((IS_ADHOC_LOC (LOC)) ? get_location_from_adhoc_loc (line_table, LOC) \
 182    : (LOC))
 183 #define LOCATION_BLOCK(LOC) \
 184   ((tree) ((IS_ADHOC_LOC (LOC)) ? get_data_from_adhoc_loc (line_table, (LOC)) \
 185    : NULL))
 186 #define RESERVED_LOCATION_P(LOC) \
 187   (LOCATION_LOCUS (LOC) < RESERVED_LOCATION_COUNT)
 188
 189 /* Return a positive value if LOCATION is the locus of a token that is
 190    located in a system header, O otherwise. It returns 1 if LOCATION
 191    is the locus of a token that is located in a system header, and 2
 192    if LOCATION is the locus of a token located in a C system header
 193    that therefore needs to be extern "C" protected in C++.
 194
 195    Note that this function returns 1 if LOCATION belongs to a token
 196    that is part of a macro replacement-list defined in a system
 197    header, but expanded in a non-system file.  */
 198
 199 inline int
 200 in_system_header_at (location_t loc)
 201 {
 202   return linemap_location_in_system_header_p (line_table, loc);
 203 }
 204
 205 /* Return true if LOCATION is the locus of a token that
 206    comes from a macro expansion, false otherwise.  */
 207
 208 inline bool
 209 from_macro_expansion_at (location_t loc)
 210 {
 211   return linemap_location_from_macro_expansion_p (line_table, loc);
 212 }
 213
 214 /* Return true if LOCATION is the locus of a token that comes from
 215    a macro definition, false otherwise.  This differs from from_macro_expansion_at
 216    in its treatment of macro arguments, for which this returns false.  */
 217
 218 inline bool
 219 from_macro_definition_at (location_t loc)
 220 {
 221   return linemap_location_from_macro_definition_p (line_table, loc);
 222 }
 223
 224 inline location_t
 225 get_pure_location (location_t loc)
 226 {
 227   return get_pure_location (line_table, loc);
 228 }
 229
 230 /* Get the start of any range encoded within location LOC.  */
 231
 232 inline location_t
 233 get_start (location_t loc)
 234 {
 235   return get_range_from_loc (line_table, loc).m_start;
 236 }
 237
 238 /* Get the endpoint of any range encoded within location LOC.  */
 239
 240 inline location_t
 241 get_finish (location_t loc)
 242 {
 243   return get_range_from_loc (line_table, loc).m_finish;
 244 }
 245
 246 extern location_t make_location (location_t caret,
 247                                  location_t start, location_t finish);
 248 extern location_t make_location (location_t caret, source_range src_range);
 249
 250 void dump_line_table_statistics (void);
 251
 252 void dump_location_info (FILE *stream);
 253
 254 void diagnostics_file_cache_fini (void);
 255
 256 void diagnostics_file_cache_forcibly_evict_file (const char *file_path);
 257
 258 class GTY(()) string_concat
 259 {
 260 public:
 261   string_concat (int num, location_t *locs);
 262
 263   int m_num;
 264   location_t * GTY ((atomic)) m_locs;
 265 };
 266
 267 class GTY(()) string_concat_db
 268 {
 269  public:
 270   string_concat_db ();
 271   void record_string_concatenation (int num, location_t *locs);
 272
 273   bool get_string_concatenation (location_t loc,
 274                                  int *out_num,
 275                                  location_t **out_locs);
 276
 277  private:
 278   static location_t get_key_loc (location_t loc);
 279
 280   /* For the fields to be private, we must grant access to the
 281      generated code in gtype-desc.cc.  */
 282
 283   friend void ::gt_ggc_mx_string_concat_db (void *x_p);
 284   friend void ::gt_pch_nx_string_concat_db (void *x_p);
 285   friend void ::gt_pch_p_16string_concat_db (void *this_obj, void *x_p,
 286                                              gt_pointer_operator op,
 287                                              void *cookie);
 288
 289   hash_map <location_hash, string_concat *> *m_table;
 290 };
 291
 292 #endif