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