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   char_span get_source_file_content (const char *file_path);
 154   char_span get_source_line (const char *file_path, int line);
 155
 156  private:
 157   file_cache_slot *evicted_cache_tab_entry (unsigned *highest_use_count);
 158   file_cache_slot *add_file (const char *file_path);
 159   file_cache_slot *lookup_file (const char *file_path);
 160
 161  private:
 162   static const size_t num_file_slots = 16;
 163   file_cache_slot *m_file_slots;
 164   input_context in_context;
 165 };
 166
 167 extern expanded_location
 168 expand_location_to_spelling_point (location_t,
 169                                    enum location_aspect aspect
 170                                      = LOCATION_ASPECT_CARET);
 171 extern location_t expansion_point_location_if_in_system_header (location_t);
 172 extern location_t expansion_point_location (location_t);
 173
 174 extern location_t input_location;
 175
 176 extern location_t location_with_discriminator (location_t, int);
 177 extern bool has_discriminator (location_t);
 178 extern int get_discriminator_from_loc (location_t);
 179
 180 #define LOCATION_FILE(LOC) ((expand_location (LOC)).file)
 181 #define LOCATION_LINE(LOC) ((expand_location (LOC)).line)
 182 #define LOCATION_COLUMN(LOC)((expand_location (LOC)).column)
 183 #define LOCATION_LOCUS(LOC) \
 184   ((IS_ADHOC_LOC (LOC)) ? get_location_from_adhoc_loc (line_table, LOC) \
 185    : (LOC))
 186 #define LOCATION_BLOCK(LOC) \
 187   ((tree) ((IS_ADHOC_LOC (LOC)) ? get_data_from_adhoc_loc (line_table, (LOC)) \
 188    : NULL))
 189 #define RESERVED_LOCATION_P(LOC) \
 190   (LOCATION_LOCUS (LOC) < RESERVED_LOCATION_COUNT)
 191
 192 /* Return a positive value if LOCATION is the locus of a token that is
 193    located in a system header, O otherwise. It returns 1 if LOCATION
 194    is the locus of a token that is located in a system header, and 2
 195    if LOCATION is the locus of a token located in a C system header
 196    that therefore needs to be extern "C" protected in C++.
 197
 198    Note that this function returns 1 if LOCATION belongs to a token
 199    that is part of a macro replacement-list defined in a system
 200    header, but expanded in a non-system file.  */
 201
 202 inline int
 203 in_system_header_at (location_t loc)
 204 {
 205   return linemap_location_in_system_header_p (line_table, loc);
 206 }
 207
 208 /* Return true if LOCATION is the locus of a token that
 209    comes from a macro expansion, false otherwise.  */
 210
 211 inline bool
 212 from_macro_expansion_at (location_t loc)
 213 {
 214   return linemap_location_from_macro_expansion_p (line_table, loc);
 215 }
 216
 217 /* Return true if LOCATION is the locus of a token that comes from
 218    a macro definition, false otherwise.  This differs from from_macro_expansion_at
 219    in its treatment of macro arguments, for which this returns false.  */
 220
 221 inline bool
 222 from_macro_definition_at (location_t loc)
 223 {
 224   return linemap_location_from_macro_definition_p (line_table, loc);
 225 }
 226
 227 inline location_t
 228 get_pure_location (location_t loc)
 229 {
 230   return get_pure_location (line_table, loc);
 231 }
 232
 233 /* Get the start of any range encoded within location LOC.  */
 234
 235 inline location_t
 236 get_start (location_t loc)
 237 {
 238   return get_range_from_loc (line_table, loc).m_start;
 239 }
 240
 241 /* Get the endpoint of any range encoded within location LOC.  */
 242
 243 inline location_t
 244 get_finish (location_t loc)
 245 {
 246   return get_range_from_loc (line_table, loc).m_finish;
 247 }
 248
 249 extern location_t make_location (location_t caret,
 250                                  location_t start, location_t finish);
 251 extern location_t make_location (location_t caret, source_range src_range);
 252
 253 void dump_line_table_statistics (void);
 254
 255 void dump_location_info (FILE *stream);
 256
 257 void diagnostics_file_cache_fini (void);
 258
 259 void diagnostics_file_cache_forcibly_evict_file (const char *file_path);
 260
 261 class GTY(()) string_concat
 262 {
 263 public:
 264   string_concat (int num, location_t *locs);
 265
 266   int m_num;
 267   location_t * GTY ((atomic)) m_locs;
 268 };
 269
 270 class GTY(()) string_concat_db
 271 {
 272  public:
 273   string_concat_db ();
 274   void record_string_concatenation (int num, location_t *locs);
 275
 276   bool get_string_concatenation (location_t loc,
 277                                  int *out_num,
 278                                  location_t **out_locs);
 279
 280  private:
 281   static location_t get_key_loc (location_t loc);
 282
 283   /* For the fields to be private, we must grant access to the
 284      generated code in gtype-desc.cc.  */
 285
 286   friend void ::gt_ggc_mx_string_concat_db (void *x_p);
 287   friend void ::gt_pch_nx_string_concat_db (void *x_p);
 288   friend void ::gt_pch_p_16string_concat_db (void *this_obj, void *x_p,
 289                                              gt_pointer_operator op,
 290                                              void *cookie);
 291
 292   hash_map <location_hash, string_concat *> *m_table;
 293 };
 294
 295 #endif