1 /* File format for coverage information 2 Copyright (C) 1996-2022 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provides 30 machine-readable coverage information. 31 32 Note that the following file format documentation might be outdated. 33 34 Coverage information is held in two files.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 The magic ident is different for the notes and the data files. The 64 magic ident is used to determine the endianness of the file, when 65 reading. The version is the same for both files and is derived 66 from gcc's version number. The stamp value is used to synchronize 67 note and data files and to synchronize merging within a data 68 file. It need not be an absolute time stamp, merely a ticker that 69 increments fast enough and cycles slow enough to distinguish 70 different compile/run/compile cycles. 71 72 Although the ident and version are formally 32 bit numbers, they 73 are derived from 4 character ASCII strings. The version number 74 consists of a two character major version number 75 (first digit starts from 'A' letter to not to clash with the older 76 numbering scheme), the single character minor version number, 77 and a single character indicating the status of the release. 78 That will be 'e' experimental, 'p' prerelease and 'r' for release. 79 Because, by good fortune, these are in alphabetical order, string 80 collating can be used to compare version strings. Be aware that 81 the 'e' designation will (naturally) be unstable and might be 82 incompatible with itself. For gcc 17.0 experimental, it would be 83 'B70e' (0x42373065). As we currently do not release more than 5 minor 84 releases, the single character should be always fine. Major number 85 is currently changed roughly every year, which gives us space 86 for next 250 years (maximum allowed number would be 259.9). 87 88 A record has a tag, length and variable amount of data. 89 90 record: header data 91 header: int32:tag int32:length 92 data: item* 93 94 Records are not nested, but there is a record hierarchy. Tag 95 numbers reflect this hierarchy. Tags are unique across note and 96 data files. Some record types have a varying amount of data. The 97 LENGTH is the number of 4bytes that follow and is usually used to 98 determine how much data. The tag value is split into 4 8-bit 99 fields, one for each of four possible levels. The most significant 100 is allocated first. Unused levels are zero. Active levels are 101 odd-valued, so that the LSB of the level is one. A sub-level 102 incorporates the values of its superlevels. This formatting allows 103 you to determine the tag hierarchy, without understanding the tags 104 themselves, and is similar to the standard section numbering used 105 in technical documents. Level values [1..3f] are used for common 106 tags, values [41..9f] for the notes file and [a1..ff] for the data 107 file. 108 109 The notes file contains the following records 110 note: unit function-graph* 111 unit: header int32:checksum string:source 112 function-graph: announce_function basic_blocks {arcs | lines}* 113 announce_function: header int32:ident 114 int32:lineno_checksum int32:cfg_checksum 115 string:name string:source int32:start_lineno int32:start_column int32:end_lineno 116 basic_block: header int32:flags* 117 arcs: header int32:block_no arc* 118 arc: int32:dest_block int32:flags 119 lines: header int32:block_no line* 120 int32:0 string:NULL 121 line: int32:line_no | int32:0 string:filename 122 123 The BASIC_BLOCK record holds per-bb flags. The number of blocks 124 can be inferred from its data length. There is one ARCS record per 125 basic block. The number of arcs from a bb is implicit from the 126 data length. It enumerates the destination bb and per-arc flags. 127 There is one LINES record per basic block, it enumerates the source 128 lines which belong to that basic block. Source file names are 129 introduced by a line number of 0, following lines are from the new 130 source file. The initial source file for the function is NULL, but 131 the current source file should be remembered from one LINES record 132 to the next. The end of a block is indicated by an empty filename 133 - this does not reset the current source file. Note there is no 134 ordering of the ARCS and LINES records: they may be in any order, 135 interleaved in any manner. The current filename follows the order 136 the LINES records are stored in the file, *not* the ordering of the 137 blocks they are for. 138 139 The data file contains the following records. 140 data: {unit summary:object function-data*}* 141 unit: header int32:checksum 142 function-data: announce_function present counts 143 announce_function: header int32:ident 144 int32:lineno_checksum int32:cfg_checksum 145 present: header int32:present 146 counts: header int64:count* 147 summary: int32:checksum int32:runs int32:sum_max 148 149 The ANNOUNCE_FUNCTION record is the same as that in the note file, 150 but without the source location. The COUNTS gives the 151 counter values for instrumented features. The about the whole 152 program. The checksum is used for whole program summaries, and 153 disambiguates different programs which include the same 154 instrumented object file. There may be several program summaries, 155 each with a unique checksum. The object summary's checksum is 156 zero. Note that the data file might contain information from 157 several runs concatenated, or the data might be merged. 158 159 This file is included by both the compiler, gcov tools and the 160 runtime support library libgcov. IN_LIBGCOV and IN_GCOV are used to 161 distinguish which case is which. If IN_LIBGCOV is nonzero, 162 libgcov is being built. If IN_GCOV is nonzero, the gcov tools are 163 being built. Otherwise the compiler is being built. IN_GCOV may be 164 positive or negative. If positive, we are compiling a tool that 165 requires additional functions (see the code for knowledge of what 166 those functions are). */ 167 168 #ifndef GCC_GCOV_IO_H 169 #define GCC_GCOV_IO_H 170 171 /* GCOV key-value pair linked list type. */ 172 173 struct gcov_kvp; 174 175 struct gcov_kvp 176 { 177 gcov_type value; 178 gcov_type count; 179 struct gcov_kvp *next; 180 }; 181 182 #ifndef IN_LIBGCOV 183 /* About the host */ 184 185 typedef unsigned gcov_unsigned_t; 186 typedef unsigned gcov_position_t; 187 /* gcov_type is typedef'd elsewhere for the compiler */ 188 #if IN_GCOV 189 #define GCOV_LINKAGE static 190 typedef int64_t gcov_type; 191 typedef uint64_t gcov_type_unsigned; 192 #if IN_GCOV > 0 193 #include <sys/types.h> 194 #endif 195 #endif 196 197 #if defined (HOST_HAS_F_SETLKW) 198 #define GCOV_LOCKED 1 199 #else 200 #define GCOV_LOCKED 0 201 #endif 202 203 #if defined (HOST_HAS_LK_LOCK) 204 #define GCOV_LOCKED_WITH_LOCKING 1 205 #else 206 #define GCOV_LOCKED_WITH_LOCKING 0 207 #endif 208 209 #define ATTRIBUTE_HIDDEN 210 211 #endif /* !IN_LIBGCOV */ 212 213 #ifndef GCOV_LINKAGE 214 #define GCOV_LINKAGE extern 215 #endif 216 217 #if IN_LIBGCOV 218 #define gcov_nonruntime_assert(EXPR) ((void)(0 && (EXPR))) 219 #else 220 #define gcov_nonruntime_assert(EXPR) gcc_assert (EXPR) 221 #define gcov_error(...) fatal_error (input_location, __VA_ARGS__) 222 #endif 223 224 /* File suffixes. */ 225 #define GCOV_DATA_SUFFIX ".gcda" 226 #define GCOV_NOTE_SUFFIX ".gcno" 227 228 /* File magic. Must not be palindromes. */ 229 #define GCOV_DATA_MAGIC ((gcov_unsigned_t)0x67636461) /* "gcda" */ 230 #define GCOV_NOTE_MAGIC ((gcov_unsigned_t)0x67636e6f) /* "gcno" */ 231 232 #include "version.h" 233 234 /* Convert a magic or version number to a 4 character string. */ 235 #define GCOV_UNSIGNED2STRING(ARRAY,VALUE) \ 236 ((ARRAY)[0] = (char)((VALUE) >> 24), \ 237 (ARRAY)[1] = (char)((VALUE) >> 16), \ 238 (ARRAY)[2] = (char)((VALUE) >> 8), \ 239 (ARRAY)[3] = (char)((VALUE) >> 0)) 240 241 /* The record tags. Values [1..3f] are for tags which may be in either 242 file. Values [41..9f] for those in the note file and [a1..ff] for 243 the data file. The tag value zero is used as an explicit end of 244 file marker -- it is not required to be present. 245 All length values are in bytes. */ 246 247 #define GCOV_WORD_SIZE 4 248 249 #define GCOV_TAG_FUNCTION ((gcov_unsigned_t)0x01000000) 250 #define GCOV_TAG_FUNCTION_LENGTH (3 * GCOV_WORD_SIZE) 251 #define GCOV_TAG_BLOCKS ((gcov_unsigned_t)0x01410000) 252 #define GCOV_TAG_BLOCKS_LENGTH(NUM) (NUM) 253 #define GCOV_TAG_ARCS ((gcov_unsigned_t)0x01430000) 254 #define GCOV_TAG_ARCS_LENGTH(NUM) (1 + (NUM) * 2 * GCOV_WORD_SIZE) 255 #define GCOV_TAG_ARCS_NUM(LENGTH) (((LENGTH / GCOV_WORD_SIZE) - 1) / 2) 256 #define GCOV_TAG_LINES ((gcov_unsigned_t)0x01450000) 257 #define GCOV_TAG_COUNTER_BASE ((gcov_unsigned_t)0x01a10000) 258 #define GCOV_TAG_COUNTER_LENGTH(NUM) ((NUM) * 2 * GCOV_WORD_SIZE) 259 #define GCOV_TAG_COUNTER_NUM(LENGTH) ((LENGTH / GCOV_WORD_SIZE) / 2) 260 #define GCOV_TAG_OBJECT_SUMMARY ((gcov_unsigned_t)0xa1000000) 261 #define GCOV_TAG_PROGRAM_SUMMARY ((gcov_unsigned_t)0xa3000000) /* Obsolete */ 262 #define GCOV_TAG_SUMMARY_LENGTH (2 * GCOV_WORD_SIZE) 263 #define GCOV_TAG_AFDO_FILE_NAMES ((gcov_unsigned_t)0xaa000000) 264 #define GCOV_TAG_AFDO_FUNCTION ((gcov_unsigned_t)0xac000000) 265 #define GCOV_TAG_AFDO_WORKING_SET ((gcov_unsigned_t)0xaf000000) 266 267 268 /* Counters that are collected. */ 269 270 #define DEF_GCOV_COUNTER(COUNTER, NAME, MERGE_FN) COUNTER, 271 enum { 272 #include "gcov-counter.def" 273 GCOV_COUNTERS 274 }; 275 #undef DEF_GCOV_COUNTER 276 277 /* The first of counters used for value profiling. They must form a 278 consecutive interval and their order must match the order of 279 HIST_TYPEs in value-prof.h. */ 280 #define GCOV_FIRST_VALUE_COUNTER GCOV_COUNTER_V_INTERVAL 281 282 /* The last of counters used for value profiling. */ 283 #define GCOV_LAST_VALUE_COUNTER (GCOV_COUNTERS - 1) 284 285 /* Number of counters used for value profiling. */ 286 #define GCOV_N_VALUE_COUNTERS \ 287 (GCOV_LAST_VALUE_COUNTER - GCOV_FIRST_VALUE_COUNTER + 1) 288 289 /* Number of top N counters when being in memory. */ 290 #define GCOV_TOPN_MEM_COUNTERS 3 291 292 /* Number of top N counters in disk representation. */ 293 #define GCOV_TOPN_DISK_COUNTERS 2 294 295 /* Maximum number of tracked TOP N value profiles. */ 296 #define GCOV_TOPN_MAXIMUM_TRACKED_VALUES 32 297 298 /* Convert a counter index to a tag. */ 299 #define GCOV_TAG_FOR_COUNTER(COUNT) \ 300 (GCOV_TAG_COUNTER_BASE + ((gcov_unsigned_t)(COUNT) << 17)) 301 /* Convert a tag to a counter. */ 302 #define GCOV_COUNTER_FOR_TAG(TAG) \ 303 ((unsigned)(((TAG) - GCOV_TAG_COUNTER_BASE) >> 17)) 304 /* Check whether a tag is a counter tag. */ 305 #define GCOV_TAG_IS_COUNTER(TAG) \ 306 (!((TAG) & 0xFFFF) && GCOV_COUNTER_FOR_TAG (TAG) < GCOV_COUNTERS) 307 308 /* The tag level mask has 1's in the position of the inner levels, & 309 the lsb of the current level, and zero on the current and outer 310 levels. */ 311 #define GCOV_TAG_MASK(TAG) (((TAG) - 1) ^ (TAG)) 312 313 /* Return nonzero if SUB is an immediate subtag of TAG. */ 314 #define GCOV_TAG_IS_SUBTAG(TAG,SUB) \ 315 (GCOV_TAG_MASK (TAG) >> 8 == GCOV_TAG_MASK (SUB) \ 316 && !(((SUB) ^ (TAG)) & ~GCOV_TAG_MASK (TAG))) 317 318 /* Return nonzero if SUB is at a sublevel to TAG. */ 319 #define GCOV_TAG_IS_SUBLEVEL(TAG,SUB) \ 320 (GCOV_TAG_MASK (TAG) > GCOV_TAG_MASK (SUB)) 321 322 /* Basic block flags. */ 323 #define GCOV_BLOCK_UNEXPECTED (1 << 1) 324 325 /* Arc flags. */ 326 #define GCOV_ARC_ON_TREE (1 << 0) 327 #define GCOV_ARC_FAKE (1 << 1) 328 #define GCOV_ARC_FALLTHROUGH (1 << 2) 329 330 /* Object & program summary record. */ 331 332 struct gcov_summary 333 { 334 gcov_unsigned_t runs; /* Number of program runs. */ 335 gcov_type sum_max; /* Sum of individual run max values. */ 336 }; 337 338 #if !defined(inhibit_libc) 339 340 /* Functions for reading and writing gcov files. In libgcov you can 341 open the file for reading then writing. Elsewhere you can open the 342 file either for reading or for writing. When reading a file you may 343 use the gcov_read_* functions, gcov_sync, gcov_position, & 344 gcov_error. When writing a file you may use the gcov_write 345 functions, gcov_seek & gcov_error. When a file is to be rewritten 346 you use the functions for reading, then gcov_rewrite then the 347 functions for writing. Your file may become corrupted if you break 348 these invariants. */ 349 350 #if !IN_LIBGCOV 351 GCOV_LINKAGE int gcov_open (const char */*name*/, int /*direction*/); 352 #endif 353 354 #if !IN_LIBGCOV || defined (IN_GCOV_TOOL) 355 GCOV_LINKAGE int gcov_magic (gcov_unsigned_t, gcov_unsigned_t); 356 #endif 357 358 /* Available everywhere. */ 359 GCOV_LINKAGE int gcov_close (void) ATTRIBUTE_HIDDEN; 360 GCOV_LINKAGE gcov_unsigned_t gcov_read_unsigned (void) ATTRIBUTE_HIDDEN; 361 GCOV_LINKAGE gcov_type gcov_read_counter (void) ATTRIBUTE_HIDDEN; 362 GCOV_LINKAGE void gcov_read_summary (struct gcov_summary *) ATTRIBUTE_HIDDEN; 363 GCOV_LINKAGE const char *gcov_read_string (void); 364 GCOV_LINKAGE void gcov_sync (gcov_position_t /*base*/, 365 gcov_unsigned_t /*length */); 366 char *mangle_path (char const *base); 367 368 #if !IN_GCOV 369 /* Available outside gcov */ 370 GCOV_LINKAGE void gcov_write (const void *, unsigned) ATTRIBUTE_HIDDEN; 371 GCOV_LINKAGE void gcov_write_unsigned (gcov_unsigned_t) ATTRIBUTE_HIDDEN; 372 #endif 373 374 #if !IN_GCOV && !IN_LIBGCOV 375 /* Available only in compiler */ 376 GCOV_LINKAGE void gcov_write_string (const char *); 377 GCOV_LINKAGE void gcov_write_filename (const char *); 378 GCOV_LINKAGE gcov_position_t gcov_write_tag (gcov_unsigned_t); 379 GCOV_LINKAGE void gcov_write_length (gcov_position_t /*position*/); 380 #endif 381 382 #if IN_GCOV > 0 383 /* Available in gcov */ 384 GCOV_LINKAGE time_t gcov_time (void); 385 #endif 386 387 #endif /* !inhibit_libc */ 388 389 #endif /* GCC_GCOV_IO_H */ 390