1 /* File format for coverage information 2 Copyright (C) 1996-2017 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 /* Coverage information is held in two files. A notes file, which is 29 generated by the compiler, and a data file, which is generated by 30 the program under test. Both files use a similar structure. We do 31 not attempt to make these files backwards compatible with previous 32 versions, as you only need coverage information when developing a 33 program. We do hold version information, so that mismatches can be 34 detected, and we use a format that allows tools to skip information 35 they do not understand or are not interested in. 36 37 Numbers are recorded in the 32 bit unsigned binary form of the 38 endianness of the machine generating the file. 64 bit numbers are 39 stored as two 32 bit numbers, the low part first. Strings are 40 padded with 1 to 4 NUL bytes, to bring the length up to a multiple 41 of 4. The number of 4 bytes is stored, followed by the padded 42 string. Zero length and NULL strings are simply stored as a length 43 of zero (they have no trailing NUL or padding). 44 45 int32: byte3 byte2 byte1 byte0 | byte0 byte1 byte2 byte3 46 int64: int32:low int32:high 47 string: int32:0 | int32:length char* char:0 padding 48 padding: | char:0 | char:0 char:0 | char:0 char:0 char:0 49 item: int32 | int64 | string 50 51 The basic format of the files is 52 53 file : int32:magic int32:version int32:stamp record* 54 55 The magic ident is different for the notes and the data files. The 56 magic ident is used to determine the endianness of the file, when 57 reading. The version is the same for both files and is derived 58 from gcc's version number. The stamp value is used to synchronize 59 note and data files and to synchronize merging within a data 60 file. It need not be an absolute time stamp, merely a ticker that 61 increments fast enough and cycles slow enough to distinguish 62 different compile/run/compile cycles. 63 64 Although the ident and version are formally 32 bit numbers, they 65 are derived from 4 character ASCII strings. The version number 66 consists of a two character major version number 67 (first digit starts from 'A' letter to not to clash with the older 68 numbering scheme), the single character minor version number, 69 and a single character indicating the status of the release. 70 That will be 'e' experimental, 'p' prerelease and 'r' for release. 71 Because, by good fortune, these are in alphabetical order, string 72 collating can be used to compare version strings. Be aware that 73 the 'e' designation will (naturally) be unstable and might be 74 incompatible with itself. For gcc 17.0 experimental, it would be 75 'B70e' (0x42373065). As we currently do not release more than 5 minor 76 releases, the single character should be always fine. Major number 77 is currently changed roughly every year, which gives us space 78 for next 250 years (maximum allowed number would be 259.9). 79 80 A record has a tag, length and variable amount of data. 81 82 record: header data 83 header: int32:tag int32:length 84 data: item* 85 86 Records are not nested, but there is a record hierarchy. Tag 87 numbers reflect this hierarchy. Tags are unique across note and 88 data files. Some record types have a varying amount of data. The 89 LENGTH is the number of 4bytes that follow and is usually used to 90 determine how much data. The tag value is split into 4 8-bit 91 fields, one for each of four possible levels. The most significant 92 is allocated first. Unused levels are zero. Active levels are 93 odd-valued, so that the LSB of the level is one. A sub-level 94 incorporates the values of its superlevels. This formatting allows 95 you to determine the tag hierarchy, without understanding the tags 96 themselves, and is similar to the standard section numbering used 97 in technical documents. Level values [1..3f] are used for common 98 tags, values [41..9f] for the notes file and [a1..ff] for the data 99 file. 100 101 The notes file contains the following records 102 note: unit function-graph* 103 unit: header int32:checksum string:source 104 function-graph: announce_function basic_blocks {arcs | lines}* 105 announce_function: header int32:ident 106 int32:lineno_checksum int32:cfg_checksum 107 string:name string:source int32:lineno 108 basic_block: header int32:flags* 109 arcs: header int32:block_no arc* 110 arc: int32:dest_block int32:flags 111 lines: header int32:block_no line* 112 int32:0 string:NULL 113 line: int32:line_no | int32:0 string:filename 114 115 The BASIC_BLOCK record holds per-bb flags. The number of blocks 116 can be inferred from its data length. There is one ARCS record per 117 basic block. The number of arcs from a bb is implicit from the 118 data length. It enumerates the destination bb and per-arc flags. 119 There is one LINES record per basic block, it enumerates the source 120 lines which belong to that basic block. Source file names are 121 introduced by a line number of 0, following lines are from the new 122 source file. The initial source file for the function is NULL, but 123 the current source file should be remembered from one LINES record 124 to the next. The end of a block is indicated by an empty filename 125 - this does not reset the current source file. Note there is no 126 ordering of the ARCS and LINES records: they may be in any order, 127 interleaved in any manner. The current filename follows the order 128 the LINES records are stored in the file, *not* the ordering of the 129 blocks they are for. 130 131 The data file contains the following records. 132 data: {unit summary:object summary:program* function-data*}* 133 unit: header int32:checksum 134 function-data: announce_function present counts 135 announce_function: header int32:ident 136 int32:lineno_checksum int32:cfg_checksum 137 present: header int32:present 138 counts: header int64:count* 139 summary: int32:checksum {count-summary}GCOV_COUNTERS_SUMMABLE 140 count-summary: int32:num int32:runs int64:sum 141 int64:max int64:sum_max histogram 142 histogram: {int32:bitvector}8 histogram-buckets* 143 histogram-buckets: int32:num int64:min int64:sum 144 145 The ANNOUNCE_FUNCTION record is the same as that in the note file, 146 but without the source location. The COUNTS gives the 147 counter values for instrumented features. The about the whole 148 program. The checksum is used for whole program summaries, and 149 disambiguates different programs which include the same 150 instrumented object file. There may be several program summaries, 151 each with a unique checksum. The object summary's checksum is 152 zero. Note that the data file might contain information from 153 several runs concatenated, or the data might be merged. 154 155 This file is included by both the compiler, gcov tools and the 156 runtime support library libgcov. IN_LIBGCOV and IN_GCOV are used to 157 distinguish which case is which. If IN_LIBGCOV is nonzero, 158 libgcov is being built. If IN_GCOV is nonzero, the gcov tools are 159 being built. Otherwise the compiler is being built. IN_GCOV may be 160 positive or negative. If positive, we are compiling a tool that 161 requires additional functions (see the code for knowledge of what 162 those functions are). */ 163 164 #ifndef GCC_GCOV_IO_H 165 #define GCC_GCOV_IO_H 166 167 #ifndef IN_LIBGCOV 168 /* About the host */ 169 170 typedef unsigned gcov_unsigned_t; 171 typedef unsigned gcov_position_t; 172 /* gcov_type is typedef'd elsewhere for the compiler */ 173 #if IN_GCOV 174 #define GCOV_LINKAGE static 175 typedef int64_t gcov_type; 176 typedef uint64_t gcov_type_unsigned; 177 #if IN_GCOV > 0 178 #include <sys/types.h> 179 #endif 180 #endif 181 182 #if defined (HOST_HAS_F_SETLKW) 183 #define GCOV_LOCKED 1 184 #else 185 #define GCOV_LOCKED 0 186 #endif 187 188 #define ATTRIBUTE_HIDDEN 189 190 #endif /* !IN_LIBGOCV */ 191 192 #ifndef GCOV_LINKAGE 193 #define GCOV_LINKAGE extern 194 #endif 195 196 #if IN_LIBGCOV 197 #define gcov_nonruntime_assert(EXPR) ((void)(0 && (EXPR))) 198 #else 199 #define gcov_nonruntime_assert(EXPR) gcc_assert (EXPR) 200 #define gcov_error(...) fatal_error (input_location, __VA_ARGS__) 201 #endif 202 203 /* File suffixes. */ 204 #define GCOV_DATA_SUFFIX ".gcda" 205 #define GCOV_NOTE_SUFFIX ".gcno" 206 207 /* File magic. Must not be palindromes. */ 208 #define GCOV_DATA_MAGIC ((gcov_unsigned_t)0x67636461) /* "gcda" */ 209 #define GCOV_NOTE_MAGIC ((gcov_unsigned_t)0x67636e6f) /* "gcno" */ 210 211 /* gcov-iov.h is automatically generated by the makefile from 212 version.c, it looks like 213 #define GCOV_VERSION ((gcov_unsigned_t)0x89abcdef) 214 */ 215 #include "gcov-iov.h" 216 217 /* Convert a magic or version number to a 4 character string. */ 218 #define GCOV_UNSIGNED2STRING(ARRAY,VALUE) \ 219 ((ARRAY)[0] = (char)((VALUE) >> 24), \ 220 (ARRAY)[1] = (char)((VALUE) >> 16), \ 221 (ARRAY)[2] = (char)((VALUE) >> 8), \ 222 (ARRAY)[3] = (char)((VALUE) >> 0)) 223 224 /* The record tags. Values [1..3f] are for tags which may be in either 225 file. Values [41..9f] for those in the note file and [a1..ff] for 226 the data file. The tag value zero is used as an explicit end of 227 file marker -- it is not required to be present. */ 228 229 #define GCOV_TAG_FUNCTION ((gcov_unsigned_t)0x01000000) 230 #define GCOV_TAG_FUNCTION_LENGTH (3) 231 #define GCOV_TAG_BLOCKS ((gcov_unsigned_t)0x01410000) 232 #define GCOV_TAG_BLOCKS_LENGTH(NUM) (NUM) 233 #define GCOV_TAG_BLOCKS_NUM(LENGTH) (LENGTH) 234 #define GCOV_TAG_ARCS ((gcov_unsigned_t)0x01430000) 235 #define GCOV_TAG_ARCS_LENGTH(NUM) (1 + (NUM) * 2) 236 #define GCOV_TAG_ARCS_NUM(LENGTH) (((LENGTH) - 1) / 2) 237 #define GCOV_TAG_LINES ((gcov_unsigned_t)0x01450000) 238 #define GCOV_TAG_COUNTER_BASE ((gcov_unsigned_t)0x01a10000) 239 #define GCOV_TAG_COUNTER_LENGTH(NUM) ((NUM) * 2) 240 #define GCOV_TAG_COUNTER_NUM(LENGTH) ((LENGTH) / 2) 241 #define GCOV_TAG_OBJECT_SUMMARY ((gcov_unsigned_t)0xa1000000) /* Obsolete */ 242 #define GCOV_TAG_PROGRAM_SUMMARY ((gcov_unsigned_t)0xa3000000) 243 #define GCOV_TAG_SUMMARY_LENGTH(NUM) \ 244 (1 + GCOV_COUNTERS_SUMMABLE * (10 + 3 * 2) + (NUM) * 5) 245 #define GCOV_TAG_AFDO_FILE_NAMES ((gcov_unsigned_t)0xaa000000) 246 #define GCOV_TAG_AFDO_FUNCTION ((gcov_unsigned_t)0xac000000) 247 #define GCOV_TAG_AFDO_WORKING_SET ((gcov_unsigned_t)0xaf000000) 248 249 250 /* Counters that are collected. */ 251 252 #define DEF_GCOV_COUNTER(COUNTER, NAME, MERGE_FN) COUNTER, 253 enum { 254 #include "gcov-counter.def" 255 GCOV_COUNTERS 256 }; 257 #undef DEF_GCOV_COUNTER 258 259 /* Counters which can be summaried. */ 260 #define GCOV_COUNTERS_SUMMABLE (GCOV_COUNTER_ARCS + 1) 261 262 /* The first of counters used for value profiling. They must form a 263 consecutive interval and their order must match the order of 264 HIST_TYPEs in value-prof.h. */ 265 #define GCOV_FIRST_VALUE_COUNTER GCOV_COUNTERS_SUMMABLE 266 267 /* The last of counters used for value profiling. */ 268 #define GCOV_LAST_VALUE_COUNTER (GCOV_COUNTERS - 1) 269 270 /* Number of counters used for value profiling. */ 271 #define GCOV_N_VALUE_COUNTERS \ 272 (GCOV_LAST_VALUE_COUNTER - GCOV_FIRST_VALUE_COUNTER + 1) 273 274 /* The number of hottest callees to be tracked. */ 275 #define GCOV_ICALL_TOPN_VAL 2 276 277 /* The number of counter entries per icall callsite. */ 278 #define GCOV_ICALL_TOPN_NCOUNTS (1 + GCOV_ICALL_TOPN_VAL * 4) 279 280 /* Convert a counter index to a tag. */ 281 #define GCOV_TAG_FOR_COUNTER(COUNT) \ 282 (GCOV_TAG_COUNTER_BASE + ((gcov_unsigned_t)(COUNT) << 17)) 283 /* Convert a tag to a counter. */ 284 #define GCOV_COUNTER_FOR_TAG(TAG) \ 285 ((unsigned)(((TAG) - GCOV_TAG_COUNTER_BASE) >> 17)) 286 /* Check whether a tag is a counter tag. */ 287 #define GCOV_TAG_IS_COUNTER(TAG) \ 288 (!((TAG) & 0xFFFF) && GCOV_COUNTER_FOR_TAG (TAG) < GCOV_COUNTERS) 289 290 /* The tag level mask has 1's in the position of the inner levels, & 291 the lsb of the current level, and zero on the current and outer 292 levels. */ 293 #define GCOV_TAG_MASK(TAG) (((TAG) - 1) ^ (TAG)) 294 295 /* Return nonzero if SUB is an immediate subtag of TAG. */ 296 #define GCOV_TAG_IS_SUBTAG(TAG,SUB) \ 297 (GCOV_TAG_MASK (TAG) >> 8 == GCOV_TAG_MASK (SUB) \ 298 && !(((SUB) ^ (TAG)) & ~GCOV_TAG_MASK (TAG))) 299 300 /* Return nonzero if SUB is at a sublevel to TAG. */ 301 #define GCOV_TAG_IS_SUBLEVEL(TAG,SUB) \ 302 (GCOV_TAG_MASK (TAG) > GCOV_TAG_MASK (SUB)) 303 304 /* Basic block flags. */ 305 #define GCOV_BLOCK_UNEXPECTED (1 << 1) 306 307 /* Arc flags. */ 308 #define GCOV_ARC_ON_TREE (1 << 0) 309 #define GCOV_ARC_FAKE (1 << 1) 310 #define GCOV_ARC_FALLTHROUGH (1 << 2) 311 312 /* Structured records. */ 313 314 /* Structure used for each bucket of the log2 histogram of counter values. */ 315 typedef struct 316 { 317 /* Number of counters whose profile count falls within the bucket. */ 318 gcov_unsigned_t num_counters; 319 /* Smallest profile count included in this bucket. */ 320 gcov_type min_value; 321 /* Cumulative value of the profile counts in this bucket. */ 322 gcov_type cum_value; 323 } gcov_bucket_type; 324 325 /* For a log2 scale histogram with each range split into 4 326 linear sub-ranges, there will be at most 64 (max gcov_type bit size) - 1 log2 327 ranges since the lowest 2 log2 values share the lowest 4 linear 328 sub-range (values 0 - 3). This is 252 total entries (63*4). */ 329 330 #define GCOV_HISTOGRAM_SIZE 252 331 332 /* How many unsigned ints are required to hold a bit vector of non-zero 333 histogram entries when the histogram is written to the gcov file. 334 This is essentially a ceiling divide by 32 bits. */ 335 #define GCOV_HISTOGRAM_BITVECTOR_SIZE (GCOV_HISTOGRAM_SIZE + 31) / 32 336 337 /* Cumulative counter data. */ 338 struct gcov_ctr_summary 339 { 340 gcov_unsigned_t num; /* number of counters. */ 341 gcov_unsigned_t runs; /* number of program runs */ 342 gcov_type sum_all; /* sum of all counters accumulated. */ 343 gcov_type run_max; /* maximum value on a single run. */ 344 gcov_type sum_max; /* sum of individual run max values. */ 345 gcov_bucket_type histogram[GCOV_HISTOGRAM_SIZE]; /* histogram of 346 counter values. */ 347 }; 348 349 /* Object & program summary record. */ 350 struct gcov_summary 351 { 352 gcov_unsigned_t checksum; /* checksum of program */ 353 struct gcov_ctr_summary ctrs[GCOV_COUNTERS_SUMMABLE]; 354 }; 355 356 #if !defined(inhibit_libc) 357 358 /* Functions for reading and writing gcov files. In libgcov you can 359 open the file for reading then writing. Elsewhere you can open the 360 file either for reading or for writing. When reading a file you may 361 use the gcov_read_* functions, gcov_sync, gcov_position, & 362 gcov_error. When writing a file you may use the gcov_write 363 functions, gcov_seek & gcov_error. When a file is to be rewritten 364 you use the functions for reading, then gcov_rewrite then the 365 functions for writing. Your file may become corrupted if you break 366 these invariants. */ 367 368 #if !IN_LIBGCOV 369 GCOV_LINKAGE int gcov_open (const char */*name*/, int /*direction*/); 370 GCOV_LINKAGE int gcov_magic (gcov_unsigned_t, gcov_unsigned_t); 371 #endif 372 373 /* Available everywhere. */ 374 GCOV_LINKAGE int gcov_close (void) ATTRIBUTE_HIDDEN; 375 GCOV_LINKAGE gcov_unsigned_t gcov_read_unsigned (void) ATTRIBUTE_HIDDEN; 376 GCOV_LINKAGE gcov_type gcov_read_counter (void) ATTRIBUTE_HIDDEN; 377 GCOV_LINKAGE void gcov_read_summary (struct gcov_summary *) ATTRIBUTE_HIDDEN; 378 GCOV_LINKAGE const char *gcov_read_string (void); 379 GCOV_LINKAGE void gcov_sync (gcov_position_t /*base*/, 380 gcov_unsigned_t /*length */); 381 382 #if !IN_GCOV 383 /* Available outside gcov */ 384 GCOV_LINKAGE void gcov_write_unsigned (gcov_unsigned_t) ATTRIBUTE_HIDDEN; 385 #endif 386 387 #if !IN_GCOV && !IN_LIBGCOV 388 /* Available only in compiler */ 389 GCOV_LINKAGE unsigned gcov_histo_index (gcov_type value); 390 GCOV_LINKAGE void gcov_write_string (const char *); 391 GCOV_LINKAGE gcov_position_t gcov_write_tag (gcov_unsigned_t); 392 GCOV_LINKAGE void gcov_write_length (gcov_position_t /*position*/); 393 #endif 394 395 #if IN_GCOV <= 0 && !IN_LIBGCOV 396 /* Available in gcov-dump and the compiler. */ 397 398 /* Number of data points in the working set summary array. Using 128 399 provides information for at least every 1% increment of the total 400 profile size. The last entry is hardwired to 99.9% of the total. */ 401 #define NUM_GCOV_WORKING_SETS 128 402 403 /* Working set size statistics for a given percentage of the entire 404 profile (sum_all from the counter summary). */ 405 typedef struct gcov_working_set_info 406 { 407 /* Number of hot counters included in this working set. */ 408 unsigned num_counters; 409 /* Smallest counter included in this working set. */ 410 gcov_type min_counter; 411 } gcov_working_set_t; 412 413 GCOV_LINKAGE void compute_working_sets (const struct gcov_ctr_summary *summary, 414 gcov_working_set_t *gcov_working_sets); 415 #endif 416 417 #if IN_GCOV > 0 418 /* Available in gcov */ 419 GCOV_LINKAGE time_t gcov_time (void); 420 #endif 421 422 #endif /* !inhibit_libc */ 423 424 #endif /* GCC_GCOV_IO_H */ 425