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) 1993-2022 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 /* line-map.cc reserves RESERVED_LOCATION_COUNT to the user.  Ensure
  36    both UNKNOWN_LOCATION and BUILTINS_LOCATION fit into that.  */
  37 STATIC_ASSERT (BUILTINS_LOCATION < RESERVED_LOCATION_COUNT);
  38
  39 /* Hasher for 'location_t' values satisfying '!RESERVED_LOCATION_P', thus able
  40    to use 'UNKNOWN_LOCATION'/'BUILTINS_LOCATION' as spare values for
  41    'Empty'/'Deleted'.  */
  42 /* Per PR103157 "'gengtype': 'typedef' causing infinite-recursion code to be
  43    generated", don't use
  44        typedef int_hash<location_t, UNKNOWN_LOCATION, BUILTINS_LOCATION>
  45          location_hash;
  46    here.
  47
  48    It works for a single-use case, but when using a 'struct'-based variant
  49        struct location_hash
  50          : int_hash<location_t, UNKNOWN_LOCATION, BUILTINS_LOCATION> {};
  51    in more than one place, 'gengtype' generates duplicate functions (thus:
  52    "error: redefinition of 'void gt_ggc_mx(location_hash&)'" etc.).
  53    Attempting to mark that one up with GTY options, we run into a 'gengtype'
  54    "parse error: expected '{', have '<'", which probably falls into category
  55    "understanding of C++ is limited", as documented in 'gcc/doc/gty.texi'.
  56
  57    Thus, use a plain ol' '#define':
  58 */
  59 #define location_hash int_hash<location_t, UNKNOWN_LOCATION, BUILTINS_LOCATION>
  60
  61 extern bool is_location_from_builtin_token (location_t);
  62 extern expanded_location expand_location (location_t);
  63
  64 class cpp_char_column_policy;
  65
  66 extern int
  67 location_compute_display_column (expanded_location exploc,
  68                                  const cpp_char_column_policy &policy);
  69
  70 /* A class capturing the bounds of a buffer, to allow for run-time
  71    bounds-checking in a checked build.  */
  72
  73 class char_span
  74 {
  75  public:
  76   char_span (const char *ptr, size_t n_elts) : m_ptr (ptr), m_n_elts (n_elts) {}
  77
  78   /* Test for a non-NULL pointer.  */
  79   operator bool() const { return m_ptr; }
  80
  81   /* Get length, not including any 0-terminator (which may not be,
  82      in fact, present).  */
  83   size_t length () const { return m_n_elts; }
  84
  85   const char *get_buffer () const { return m_ptr; }
  86
  87   char operator[] (int idx) const
  88   {
  89     gcc_assert (idx >= 0);
  90     gcc_assert ((size_t)idx < m_n_elts);
  91     return m_ptr[idx];
  92   }
  93
  94   char_span subspan (int offset, int n_elts) const
  95   {
  96     gcc_assert (offset >= 0);
  97     gcc_assert (offset < (int)m_n_elts);
  98     gcc_assert (n_elts >= 0);
  99     gcc_assert (offset + n_elts <= (int)m_n_elts);
 100     return char_span (m_ptr + offset, n_elts);
 101   }
 102
 103   char *xstrdup () const
 104   {
 105     return ::xstrndup (m_ptr, m_n_elts);
 106   }
 107
 108  private:
 109   const char *m_ptr;
 110   size_t m_n_elts;
 111 };
 112
 113 extern char_span location_get_source_line (const char *file_path, int line);
 114
 115 extern bool location_missing_trailing_newline (const char *file_path);
 116
 117 /* Forward decl of slot within file_cache, so that the definition doesn't
 118    need to be in this header.  */
 119 class file_cache_slot;
 120
 121 /* A cache of source files for use when emitting diagnostics
 122    (and in a few places in the C/C++ frontends).
 123
 124    Results are only valid until the next call to the cache, as
 125    slots can be evicted.
 126
 127    Filenames are stored by pointer, and so must outlive the cache
 128    instance.  */
 129
 130 class file_cache
 131 {
 132  public:
 133   file_cache ();
 134   ~file_cache ();
 135
 136   file_cache_slot *lookup_or_add_file (const char *file_path);
 137   void forcibly_evict_file (const char *file_path);
 138
 139   /* See comments in diagnostic.h about the input conversion context.  */
 140   struct input_context
 141   {
 142     diagnostic_input_charset_callback ccb;
 143     bool should_skip_bom;
 144   };
 145   void initialize_input_context (diagnostic_input_charset_callback ccb,
 146                                  bool should_skip_bom);
 147
 148  private:
 149   file_cache_slot *evicted_cache_tab_entry (unsigned *highest_use_count);
 150   file_cache_slot *add_file (const char *file_path);
 151   file_cache_slot *lookup_file (const char *file_path);
 152
 153  private:
 154   static const size_t num_file_slots = 16;
 155   file_cache_slot *m_file_slots;
 156   input_context in_context;
 157 };
 158
 159 extern expanded_location
 160 expand_location_to_spelling_point (location_t,
 161                                    enum location_aspect aspect
 162                                      = LOCATION_ASPECT_CARET);
 163 extern location_t expansion_point_location_if_in_system_header (location_t);
 164 extern location_t expansion_point_location (location_t);
 165
 166 extern location_t input_location;
 167
 168 extern location_t location_with_discriminator (location_t, int);
 169 extern bool has_discriminator (location_t);
 170 extern int get_discriminator_from_loc (location_t);
 171
 172 #define LOCATION_FILE(LOC) ((expand_location (LOC)).file)
 173 #define LOCATION_LINE(LOC) ((expand_location (LOC)).line)
 174 #define LOCATION_COLUMN(LOC)((expand_location (LOC)).column)
 175 #define LOCATION_LOCUS(LOC) \
 176   ((IS_ADHOC_LOC (LOC)) ? get_location_from_adhoc_loc (line_table, LOC) \
 177    : (LOC))
 178 #define LOCATION_BLOCK(LOC) \
 179   ((tree) ((IS_ADHOC_LOC (LOC)) ? get_data_from_adhoc_loc (line_table, (LOC)) \
 180    : NULL))
 181 #define RESERVED_LOCATION_P(LOC) \
 182   (LOCATION_LOCUS (LOC) < RESERVED_LOCATION_COUNT)
 183
 184 /* Return a positive value if LOCATION is the locus of a token that is
 185    located in a system header, O otherwise. It returns 1 if LOCATION
 186    is the locus of a token that is located in a system header, and 2
 187    if LOCATION is the locus of a token located in a C system header
 188    that therefore needs to be extern "C" protected in C++.
 189
 190    Note that this function returns 1 if LOCATION belongs to a token
 191    that is part of a macro replacement-list defined in a system
 192    header, but expanded in a non-system file.  */
 193
 194 static inline int
 195 in_system_header_at (location_t loc)
 196 {
 197   return linemap_location_in_system_header_p (line_table, loc);
 198 }
 199
 200 /* Return true if LOCATION is the locus of a token that
 201    comes from a macro expansion, false otherwise.  */
 202
 203 static inline bool
 204 from_macro_expansion_at (location_t loc)
 205 {
 206   return linemap_location_from_macro_expansion_p (line_table, loc);
 207 }
 208
 209 /* Return true if LOCATION is the locus of a token that comes from
 210    a macro definition, false otherwise.  This differs from from_macro_expansion_at
 211    in its treatment of macro arguments, for which this returns false.  */
 212
 213 static inline bool
 214 from_macro_definition_at (location_t loc)
 215 {
 216   return linemap_location_from_macro_definition_p (line_table, loc);
 217 }
 218
 219 static inline location_t
 220 get_pure_location (location_t loc)
 221 {
 222   return get_pure_location (line_table, loc);
 223 }
 224
 225 /* Get the start of any range encoded within location LOC.  */
 226
 227 static inline location_t
 228 get_start (location_t loc)
 229 {
 230   return get_range_from_loc (line_table, loc).m_start;
 231 }
 232
 233 /* Get the endpoint of any range encoded within location LOC.  */
 234
 235 static inline location_t
 236 get_finish (location_t loc)
 237 {
 238   return get_range_from_loc (line_table, loc).m_finish;
 239 }
 240
 241 extern location_t make_location (location_t caret,
 242                                  location_t start, location_t finish);
 243 extern location_t make_location (location_t caret, source_range src_range);
 244
 245 void dump_line_table_statistics (void);
 246
 247 void dump_location_info (FILE *stream);
 248
 249 void diagnostics_file_cache_fini (void);
 250
 251 void diagnostics_file_cache_forcibly_evict_file (const char *file_path);
 252
 253 class GTY(()) string_concat
 254 {
 255 public:
 256   string_concat (int num, location_t *locs);
 257
 258   int m_num;
 259   location_t * GTY ((atomic)) m_locs;
 260 };
 261
 262 class GTY(()) string_concat_db
 263 {
 264  public:
 265   string_concat_db ();
 266   void record_string_concatenation (int num, location_t *locs);
 267
 268   bool get_string_concatenation (location_t loc,
 269                                  int *out_num,
 270                                  location_t **out_locs);
 271
 272  private:
 273   static location_t get_key_loc (location_t loc);
 274
 275   /* For the fields to be private, we must grant access to the
 276      generated code in gtype-desc.cc.  */
 277
 278   friend void ::gt_ggc_mx_string_concat_db (void *x_p);
 279   friend void ::gt_pch_nx_string_concat_db (void *x_p);
 280   friend void ::gt_pch_p_16string_concat_db (void *this_obj, void *x_p,
 281                                              gt_pointer_operator op,
 282                                              void *cookie);
 283
 284   hash_map <location_hash, string_concat *> *m_table;
 285 };
 286
 287 #endif