1 | /* File format for coverage information |
2 | Copyright (C) 1996-2023 Free Software Foundation, Inc. |
3 | Contributed by Bob Manson <manson@cygnus.com>. |
4 | Completely remangled by Nathan Sidwell <nathan@codesourcery.com>. |
5 | |
6 | This file is part of GCC. |
7 | |
8 | GCC is free software; you can redistribute it and/or modify it under |
9 | the terms of the GNU General Public License as published by the Free |
10 | Software Foundation; either version 3, or (at your option) any later |
11 | version. |
12 | |
13 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
14 | WARRANTY; without even the implied warranty of MERCHANTABILITY or |
15 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
16 | for more details. |
17 | |
18 | Under Section 7 of GPL version 3, you are granted additional |
19 | permissions described in the GCC Runtime Library Exception, version |
20 | 3.1, as published by the Free Software Foundation. |
21 | |
22 | You should have received a copy of the GNU General Public License and |
23 | a copy of the GCC Runtime Library Exception along with this program; |
24 | see the files COPYING3 and COPYING.RUNTIME respectively. If not, see |
25 | <http://www.gnu.org/licenses/>. */ |
26 | |
27 | |
28 | /* CAVEAT: Coverage information files should not be parsed directly, |
29 | instead use `gcov --json-format`, which provides |
30 | machine-readable coverage information. |
31 | |
32 | Note that the following file format documentation might be outdated. |
33 | |
34 | Coverage information is held in two files. A notes file, which is |
35 | generated by the compiler, and a data file, which is generated by |
36 | the program under test. Both files use a similar structure. We do |
37 | not attempt to make these files backwards compatible with previous |
38 | versions, as you only need coverage information when developing a |
39 | program. We do hold version information, so that mismatches can be |
40 | detected, and we use a format that allows tools to skip information |
41 | they do not understand or are not interested in. |
42 | |
43 | Numbers are recorded in the 32 bit unsigned binary form of the |
44 | endianness of the machine generating the file. 64 bit numbers are |
45 | stored as two 32 bit numbers, the low part first. |
46 | The number of bytes is stored, followed by the |
47 | string. Zero length and NULL strings are simply stored as a length |
48 | of zero (they have no trailing NUL). |
49 | |
50 | int32: byte3 byte2 byte1 byte0 | byte0 byte1 byte2 byte3 |
51 | int64: int32:low int32:high |
52 | string: int32:0 | int32:length char* char:0 |
53 | item: int32 | int64 | string |
54 | |
55 | The basic format of the notes file is |
56 | |
57 | file : int32:magic int32:version int32:stamp int32:support_unexecuted_blocks record* |
58 | |
59 | The basic format of the data file is |
60 | |
61 | file : int32:magic int32:version int32:stamp record* |
62 | |
63 | A filename header may be used to provide a filename for the data in |
64 | a stream of data to support gcov in freestanding environments. This |
65 | header is used by the merge-stream subcommand of the gcov-tool. The |
66 | format of the filename header is |
67 | |
68 | filename-header : int32:magic int32:version string |
69 | |
70 | The magic ident is different for the notes and the data files as |
71 | well as the filename header. The magic ident is used to determine |
72 | the endianness of the file, when reading. The version is the same |
73 | for both files and is derived from gcc's version number. The stamp |
74 | value is used to synchronize note and data files and to synchronize |
75 | merging within a data file. It need not be an absolute time stamp, |
76 | merely a ticker that increments fast enough and cycles slow enough |
77 | to distinguish different compile/run/compile cycles. |
78 | |
79 | Although the ident and version are formally 32 bit numbers, they |
80 | are derived from 4 character ASCII strings. The version number |
81 | consists of a two character major version number |
82 | (first digit starts from 'A' letter to not to clash with the older |
83 | numbering scheme), the single character minor version number, |
84 | and a single character indicating the status of the release. |
85 | That will be 'e' experimental, 'p' prerelease and 'r' for release. |
86 | Because, by good fortune, these are in alphabetical order, string |
87 | collating can be used to compare version strings. Be aware that |
88 | the 'e' designation will (naturally) be unstable and might be |
89 | incompatible with itself. For gcc 17.0 experimental, it would be |
90 | 'B70e' (0x42373065). As we currently do not release more than 5 minor |
91 | releases, the single character should be always fine. Major number |
92 | is currently changed roughly every year, which gives us space |
93 | for next 250 years (maximum allowed number would be 259.9). |
94 | |
95 | A record has a tag, length and variable amount of data. |
96 | |
97 | record: header data |
98 | header: int32:tag int32:length |
99 | data: item* |
100 | |
101 | Records are not nested, but there is a record hierarchy. Tag |
102 | numbers reflect this hierarchy. Tags are unique across note and |
103 | data files. Some record types have a varying amount of data. The |
104 | LENGTH is the number of bytes that follow and is usually used to |
105 | determine how much data. The tag value is split into 4 8-bit |
106 | fields, one for each of four possible levels. The most significant |
107 | is allocated first. Unused levels are zero. Active levels are |
108 | odd-valued, so that the LSB of the level is one. A sub-level |
109 | incorporates the values of its superlevels. This formatting allows |
110 | you to determine the tag hierarchy, without understanding the tags |
111 | themselves, and is similar to the standard section numbering used |
112 | in technical documents. Level values [1..3f] are used for common |
113 | tags, values [41..9f] for the notes file and [a1..ff] for the data |
114 | file. |
115 | |
116 | The notes file contains the following records |
117 | note: unit function-graph* |
118 | unit: header int32:checksum string:source |
119 | function-graph: announce_function basic_blocks {arcs | lines}* |
120 | announce_function: header int32:ident |
121 | int32:lineno_checksum int32:cfg_checksum |
122 | string:name string:source int32:start_lineno int32:start_column int32:end_lineno |
123 | basic_block: header int32:flags* |
124 | arcs: header int32:block_no arc* |
125 | arc: int32:dest_block int32:flags |
126 | lines: header int32:block_no line* |
127 | int32:0 string:NULL |
128 | line: int32:line_no | int32:0 string:filename |
129 | |
130 | The BASIC_BLOCK record holds per-bb flags. The number of blocks |
131 | can be inferred from its data length. There is one ARCS record per |
132 | basic block. The number of arcs from a bb is implicit from the |
133 | data length. It enumerates the destination bb and per-arc flags. |
134 | There is one LINES record per basic block, it enumerates the source |
135 | lines which belong to that basic block. Source file names are |
136 | introduced by a line number of 0, following lines are from the new |
137 | source file. The initial source file for the function is NULL, but |
138 | the current source file should be remembered from one LINES record |
139 | to the next. The end of a block is indicated by an empty filename |
140 | - this does not reset the current source file. Note there is no |
141 | ordering of the ARCS and LINES records: they may be in any order, |
142 | interleaved in any manner. The current filename follows the order |
143 | the LINES records are stored in the file, *not* the ordering of the |
144 | blocks they are for. |
145 | |
146 | The data file contains the following records. |
147 | data: {unit summary:object function-data*}* |
148 | unit: header int32:checksum |
149 | function-data: announce_function present counts |
150 | announce_function: header int32:ident |
151 | int32:lineno_checksum int32:cfg_checksum |
152 | present: header int32:present |
153 | counts: header int64:count* |
154 | summary: int32:checksum int32:runs int32:sum_max |
155 | |
156 | The ANNOUNCE_FUNCTION record is the same as that in the note file, |
157 | but without the source location. The COUNTS gives the |
158 | counter values for instrumented features. The about the whole |
159 | program. The checksum is used for whole program summaries, and |
160 | disambiguates different programs which include the same |
161 | instrumented object file. There may be several program summaries, |
162 | each with a unique checksum. The object summary's checksum is |
163 | zero. Note that the data file might contain information from |
164 | several runs concatenated, or the data might be merged. |
165 | |
166 | This file is included by both the compiler, gcov tools and the |
167 | runtime support library libgcov. IN_LIBGCOV and IN_GCOV are used to |
168 | distinguish which case is which. If IN_LIBGCOV is nonzero, |
169 | libgcov is being built. If IN_GCOV is nonzero, the gcov tools are |
170 | being built. Otherwise the compiler is being built. IN_GCOV may be |
171 | positive or negative. If positive, we are compiling a tool that |
172 | requires additional functions (see the code for knowledge of what |
173 | those functions are). */ |
174 | |
175 | #ifndef GCC_GCOV_IO_H |
176 | #define GCC_GCOV_IO_H |
177 | |
178 | /* GCOV key-value pair linked list type. */ |
179 | |
180 | struct gcov_kvp; |
181 | |
182 | struct gcov_kvp |
183 | { |
184 | gcov_type value; |
185 | gcov_type count; |
186 | struct gcov_kvp *next; |
187 | }; |
188 | |
189 | #ifndef IN_LIBGCOV |
190 | /* About the host */ |
191 | |
192 | typedef unsigned gcov_unsigned_t; |
193 | typedef unsigned gcov_position_t; |
194 | /* gcov_type is typedef'd elsewhere for the compiler */ |
195 | #if IN_GCOV |
196 | #define GCOV_LINKAGE static |
197 | typedef int64_t gcov_type; |
198 | typedef uint64_t gcov_type_unsigned; |
199 | #if IN_GCOV > 0 |
200 | #include <sys/types.h> |
201 | #endif |
202 | #endif |
203 | |
204 | #if defined (HOST_HAS_F_SETLKW) |
205 | #define GCOV_LOCKED 1 |
206 | #else |
207 | #define GCOV_LOCKED 0 |
208 | #endif |
209 | |
210 | #if defined (HOST_HAS_LK_LOCK) |
211 | #define GCOV_LOCKED_WITH_LOCKING 1 |
212 | #else |
213 | #define GCOV_LOCKED_WITH_LOCKING 0 |
214 | #endif |
215 | |
216 | #define ATTRIBUTE_HIDDEN |
217 | |
218 | #endif /* !IN_LIBGCOV */ |
219 | |
220 | #ifndef GCOV_LINKAGE |
221 | #define GCOV_LINKAGE extern |
222 | #endif |
223 | |
224 | #if IN_LIBGCOV |
225 | #define gcov_nonruntime_assert(EXPR) ((void)(0 && (EXPR))) |
226 | #else |
227 | #define gcov_nonruntime_assert(EXPR) gcc_assert (EXPR) |
228 | #define gcov_error(...) fatal_error (input_location, __VA_ARGS__) |
229 | #endif |
230 | |
231 | /* File suffixes. */ |
232 | #define GCOV_DATA_SUFFIX ".gcda" |
233 | #define GCOV_NOTE_SUFFIX ".gcno" |
234 | |
235 | /* File magic. Must not be palindromes. */ |
236 | #define GCOV_DATA_MAGIC ((gcov_unsigned_t)0x67636461) /* "gcda" */ |
237 | #define GCOV_NOTE_MAGIC ((gcov_unsigned_t)0x67636e6f) /* "gcno" */ |
238 | #define GCOV_FILENAME_MAGIC ((gcov_unsigned_t)0x6763666e) /* "gcfn" */ |
239 | |
240 | #include "version.h" |
241 | |
242 | /* Convert a magic or version number to a 4 character string. */ |
243 | #define GCOV_UNSIGNED2STRING(ARRAY,VALUE) \ |
244 | ((ARRAY)[0] = (char)((VALUE) >> 24), \ |
245 | (ARRAY)[1] = (char)((VALUE) >> 16), \ |
246 | (ARRAY)[2] = (char)((VALUE) >> 8), \ |
247 | (ARRAY)[3] = (char)((VALUE) >> 0)) |
248 | |
249 | /* The record tags. Values [1..3f] are for tags which may be in either |
250 | file. Values [41..9f] for those in the note file and [a1..ff] for |
251 | the data file. The tag value zero is used as an explicit end of |
252 | file marker -- it is not required to be present. |
253 | All length values are in bytes. */ |
254 | |
255 | #define GCOV_WORD_SIZE 4 |
256 | |
257 | #define GCOV_TAG_FUNCTION ((gcov_unsigned_t)0x01000000) |
258 | #define GCOV_TAG_FUNCTION_LENGTH (3 * GCOV_WORD_SIZE) |
259 | #define GCOV_TAG_BLOCKS ((gcov_unsigned_t)0x01410000) |
260 | #define GCOV_TAG_BLOCKS_LENGTH(NUM) (NUM) |
261 | #define GCOV_TAG_ARCS ((gcov_unsigned_t)0x01430000) |
262 | #define GCOV_TAG_ARCS_LENGTH(NUM) (1 + (NUM) * 2 * GCOV_WORD_SIZE) |
263 | #define GCOV_TAG_ARCS_NUM(LENGTH) (((LENGTH / GCOV_WORD_SIZE) - 1) / 2) |
264 | #define GCOV_TAG_LINES ((gcov_unsigned_t)0x01450000) |
265 | #define GCOV_TAG_COUNTER_BASE ((gcov_unsigned_t)0x01a10000) |
266 | #define GCOV_TAG_COUNTER_LENGTH(NUM) ((NUM) * 2 * GCOV_WORD_SIZE) |
267 | #define GCOV_TAG_COUNTER_NUM(LENGTH) ((LENGTH / GCOV_WORD_SIZE) / 2) |
268 | #define GCOV_TAG_OBJECT_SUMMARY ((gcov_unsigned_t)0xa1000000) |
269 | #define GCOV_TAG_OBJECT_SUMMARY_LENGTH (2 * GCOV_WORD_SIZE) |
270 | #define GCOV_TAG_PROGRAM_SUMMARY ((gcov_unsigned_t)0xa3000000) /* Obsolete */ |
271 | #define GCOV_TAG_AFDO_FILE_NAMES ((gcov_unsigned_t)0xaa000000) |
272 | #define GCOV_TAG_AFDO_FUNCTION ((gcov_unsigned_t)0xac000000) |
273 | #define GCOV_TAG_AFDO_WORKING_SET ((gcov_unsigned_t)0xaf000000) |
274 | |
275 | |
276 | /* Counters that are collected. */ |
277 | |
278 | #define DEF_GCOV_COUNTER(COUNTER, NAME, MERGE_FN) COUNTER, |
279 | enum { |
280 | #include "gcov-counter.def" |
281 | GCOV_COUNTERS |
282 | }; |
283 | #undef DEF_GCOV_COUNTER |
284 | |
285 | /* The first of counters used for value profiling. They must form a |
286 | consecutive interval and their order must match the order of |
287 | HIST_TYPEs in value-prof.h. */ |
288 | #define GCOV_FIRST_VALUE_COUNTER GCOV_COUNTER_V_INTERVAL |
289 | |
290 | /* The last of counters used for value profiling. */ |
291 | #define GCOV_LAST_VALUE_COUNTER (GCOV_COUNTERS - 1) |
292 | |
293 | /* Number of counters used for value profiling. */ |
294 | #define GCOV_N_VALUE_COUNTERS \ |
295 | (GCOV_LAST_VALUE_COUNTER - GCOV_FIRST_VALUE_COUNTER + 1) |
296 | |
297 | /* Number of top N counters when being in memory. */ |
298 | #define GCOV_TOPN_MEM_COUNTERS 3 |
299 | |
300 | /* Number of top N counters in disk representation. */ |
301 | #define GCOV_TOPN_DISK_COUNTERS 2 |
302 | |
303 | /* Maximum number of tracked TOP N value profiles. */ |
304 | #define GCOV_TOPN_MAXIMUM_TRACKED_VALUES 32 |
305 | |
306 | /* Convert a counter index to a tag. */ |
307 | #define GCOV_TAG_FOR_COUNTER(COUNT) \ |
308 | (GCOV_TAG_COUNTER_BASE + ((gcov_unsigned_t)(COUNT) << 17)) |
309 | /* Convert a tag to a counter. */ |
310 | #define GCOV_COUNTER_FOR_TAG(TAG) \ |
311 | ((unsigned)(((TAG) - GCOV_TAG_COUNTER_BASE) >> 17)) |
312 | /* Check whether a tag is a counter tag. */ |
313 | #define GCOV_TAG_IS_COUNTER(TAG) \ |
314 | (!((TAG) & 0xFFFF) && GCOV_COUNTER_FOR_TAG (TAG) < GCOV_COUNTERS) |
315 | |
316 | /* The tag level mask has 1's in the position of the inner levels, & |
317 | the lsb of the current level, and zero on the current and outer |
318 | levels. */ |
319 | #define GCOV_TAG_MASK(TAG) (((TAG) - 1) ^ (TAG)) |
320 | |
321 | /* Return nonzero if SUB is an immediate subtag of TAG. */ |
322 | #define GCOV_TAG_IS_SUBTAG(TAG,SUB) \ |
323 | (GCOV_TAG_MASK (TAG) >> 8 == GCOV_TAG_MASK (SUB) \ |
324 | && !(((SUB) ^ (TAG)) & ~GCOV_TAG_MASK (TAG))) |
325 | |
326 | /* Return nonzero if SUB is at a sublevel to TAG. */ |
327 | #define GCOV_TAG_IS_SUBLEVEL(TAG,SUB) \ |
328 | (GCOV_TAG_MASK (TAG) > GCOV_TAG_MASK (SUB)) |
329 | |
330 | /* Basic block flags. */ |
331 | #define GCOV_BLOCK_UNEXPECTED (1 << 1) |
332 | |
333 | /* Arc flags. */ |
334 | #define GCOV_ARC_ON_TREE (1 << 0) |
335 | #define GCOV_ARC_FAKE (1 << 1) |
336 | #define GCOV_ARC_FALLTHROUGH (1 << 2) |
337 | |
338 | /* Object & program summary record. */ |
339 | |
340 | struct gcov_summary |
341 | { |
342 | gcov_unsigned_t runs; /* Number of program runs. */ |
343 | gcov_type sum_max; /* Sum of individual run max values. */ |
344 | }; |
345 | |
346 | #if !defined(inhibit_libc) |
347 | |
348 | /* Functions for reading and writing gcov files. In libgcov you can |
349 | open the file for reading then writing. Elsewhere you can open the |
350 | file either for reading or for writing. When reading a file you may |
351 | use the gcov_read_* functions, gcov_sync, gcov_position, and |
352 | gcov_error. When writing a file you may use the gcov_write* |
353 | functions and gcov_error. When a file is to be rewritten |
354 | you use the functions for reading, then gcov_rewrite then the |
355 | functions for writing. Your file may become corrupted if you break |
356 | these invariants. */ |
357 | |
358 | #if !IN_LIBGCOV || defined (IN_GCOV_TOOL) |
359 | GCOV_LINKAGE int gcov_magic (gcov_unsigned_t, gcov_unsigned_t); |
360 | #endif |
361 | |
362 | /* Available everywhere. */ |
363 | GCOV_LINKAGE int gcov_open (const char *, int) ATTRIBUTE_HIDDEN; |
364 | GCOV_LINKAGE int gcov_close (void) ATTRIBUTE_HIDDEN; |
365 | GCOV_LINKAGE gcov_unsigned_t gcov_read_unsigned (void) ATTRIBUTE_HIDDEN; |
366 | GCOV_LINKAGE gcov_type gcov_read_counter (void) ATTRIBUTE_HIDDEN; |
367 | GCOV_LINKAGE void gcov_read_summary (struct gcov_summary *) ATTRIBUTE_HIDDEN; |
368 | GCOV_LINKAGE const char *gcov_read_string (void); |
369 | GCOV_LINKAGE void gcov_sync (gcov_position_t /*base*/, |
370 | gcov_unsigned_t /*length */); |
371 | char *mangle_path (char const *base); |
372 | |
373 | #if !IN_GCOV |
374 | /* Available outside gcov */ |
375 | GCOV_LINKAGE void gcov_write (const void *, unsigned) ATTRIBUTE_HIDDEN; |
376 | GCOV_LINKAGE void gcov_write_unsigned (gcov_unsigned_t) ATTRIBUTE_HIDDEN; |
377 | #endif |
378 | |
379 | #if !IN_GCOV && !IN_LIBGCOV |
380 | /* Available only in compiler */ |
381 | GCOV_LINKAGE void gcov_write_string (const char *); |
382 | GCOV_LINKAGE void gcov_write_filename (const char *); |
383 | GCOV_LINKAGE gcov_position_t gcov_write_tag (gcov_unsigned_t); |
384 | GCOV_LINKAGE void gcov_write_length (gcov_position_t /*position*/); |
385 | #endif |
386 | |
387 | #if IN_GCOV > 0 |
388 | /* Available in gcov */ |
389 | GCOV_LINKAGE time_t gcov_time (void); |
390 | #endif |
391 | |
392 | #endif /* !inhibit_libc */ |
393 | |
394 | #endif /* GCC_GCOV_IO_H */ |
395 | |