1 /* File format for coverage information 2 Copyright (C) 1996-2020 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 notes file is 52 53 file : int32:magic int32:version int32:stamp int32:support_unexecuted_blocks record* 54 55 The basic format of the data file is 56 57 file : int32:magic int32:version int32:stamp record* 58 59 The magic ident is different for the notes and the data files. The 60 magic ident is used to determine the endianness of the file, when 61 reading. The version is the same for both files and is derived 62 from gcc's version number. The stamp value is used to synchronize 63 note and data files and to synchronize merging within a data 64 file. It need not be an absolute time stamp, merely a ticker that 65 increments fast enough and cycles slow enough to distinguish 66 different compile/run/compile cycles. 67 68 Although the ident and version are formally 32 bit numbers, they 69 are derived from 4 character ASCII strings. The version number 70 consists of a two character major version number 71 (first digit starts from 'A' letter to not to clash with the older 72 numbering scheme), the single character minor version number, 73 and a single character indicating the status of the release. 74 That will be 'e' experimental, 'p' prerelease and 'r' for release. 75 Because, by good fortune, these are in alphabetical order, string 76 collating can be used to compare version strings. Be aware that 77 the 'e' designation will (naturally) be unstable and might be 78 incompatible with itself. For gcc 17.0 experimental, it would be 79 'B70e' (0x42373065). As we currently do not release more than 5 minor 80 releases, the single character should be always fine. Major number 81 is currently changed roughly every year, which gives us space 82 for next 250 years (maximum allowed number would be 259.9). 83 84 A record has a tag, length and variable amount of data. 85 86 record: header data 87 header: int32:tag int32:length 88 data: item* 89 90 Records are not nested, but there is a record hierarchy. Tag 91 numbers reflect this hierarchy. Tags are unique across note and 92 data files. Some record types have a varying amount of data. The 93 LENGTH is the number of 4bytes that follow and is usually used to 94 determine how much data. The tag value is split into 4 8-bit 95 fields, one for each of four possible levels. The most significant 96 is allocated first. Unused levels are zero. Active levels are 97 odd-valued, so that the LSB of the level is one. A sub-level 98 incorporates the values of its superlevels. This formatting allows 99 you to determine the tag hierarchy, without understanding the tags 100 themselves, and is similar to the standard section numbering used 101 in technical documents. Level values [1..3f] are used for common 102 tags, values [41..9f] for the notes file and [a1..ff] for the data 103 file. 104 105 The notes file contains the following records 106 note: unit function-graph* 107 unit: header int32:checksum string:source 108 function-graph: announce_function basic_blocks {arcs | lines}* 109 announce_function: header int32:ident 110 int32:lineno_checksum int32:cfg_checksum 111 string:name string:source int32:start_lineno int32:start_column int32:end_lineno 112 basic_block: header int32:flags* 113 arcs: header int32:block_no arc* 114 arc: int32:dest_block int32:flags 115 lines: header int32:block_no line* 116 int32:0 string:NULL 117 line: int32:line_no | int32:0 string:filename 118 119 The BASIC_BLOCK record holds per-bb flags. The number of blocks 120 can be inferred from its data length. There is one ARCS record per 121 basic block. The number of arcs from a bb is implicit from the 122 data length. It enumerates the destination bb and per-arc flags. 123 There is one LINES record per basic block, it enumerates the source 124 lines which belong to that basic block. Source file names are 125 introduced by a line number of 0, following lines are from the new 126 source file. The initial source file for the function is NULL, but 127 the current source file should be remembered from one LINES record 128 to the next. The end of a block is indicated by an empty filename 129 - this does not reset the current source file. Note there is no 130 ordering of the ARCS and LINES records: they may be in any order, 131 interleaved in any manner. The current filename follows the order 132 the LINES records are stored in the file, *not* the ordering of the 133 blocks they are for. 134 135 The data file contains the following records. 136 data: {unit summary:object function-data*}* 137 unit: header int32:checksum 138 function-data: announce_function present counts 139 announce_function: header int32:ident 140 int32:lineno_checksum int32:cfg_checksum 141 present: header int32:present 142 counts: header int64:count* 143 summary: int32:checksum int32:runs int32:sum_max 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_LIBGCOV */ 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_ARCS ((gcov_unsigned_t)0x01430000) 234 #define GCOV_TAG_ARCS_LENGTH(NUM) (1 + (NUM) * 2) 235 #define GCOV_TAG_ARCS_NUM(LENGTH) (((LENGTH) - 1) / 2) 236 #define GCOV_TAG_LINES ((gcov_unsigned_t)0x01450000) 237 #define GCOV_TAG_COUNTER_BASE ((gcov_unsigned_t)0x01a10000) 238 #define GCOV_TAG_COUNTER_LENGTH(NUM) ((NUM) * 2) 239 #define GCOV_TAG_COUNTER_NUM(LENGTH) ((LENGTH) / 2) 240 #define GCOV_TAG_OBJECT_SUMMARY ((gcov_unsigned_t)0xa1000000) 241 #define GCOV_TAG_PROGRAM_SUMMARY ((gcov_unsigned_t)0xa3000000) /* Obsolete */ 242 #define GCOV_TAG_SUMMARY_LENGTH (2) 243 #define GCOV_TAG_AFDO_FILE_NAMES ((gcov_unsigned_t)0xaa000000) 244 #define GCOV_TAG_AFDO_FUNCTION ((gcov_unsigned_t)0xac000000) 245 #define GCOV_TAG_AFDO_WORKING_SET ((gcov_unsigned_t)0xaf000000) 246 247 248 /* Counters that are collected. */ 249 250 #define DEF_GCOV_COUNTER(COUNTER, NAME, MERGE_FN) COUNTER, 251 enum { 252 #include "gcov-counter.def" 253 GCOV_COUNTERS 254 }; 255 #undef DEF_GCOV_COUNTER 256 257 /* The first of counters used for value profiling. They must form a 258 consecutive interval and their order must match the order of 259 HIST_TYPEs in value-prof.h. */ 260 #define GCOV_FIRST_VALUE_COUNTER GCOV_COUNTER_V_INTERVAL 261 262 /* The last of counters used for value profiling. */ 263 #define GCOV_LAST_VALUE_COUNTER (GCOV_COUNTERS - 1) 264 265 /* Number of counters used for value profiling. */ 266 #define GCOV_N_VALUE_COUNTERS \ 267 (GCOV_LAST_VALUE_COUNTER - GCOV_FIRST_VALUE_COUNTER + 1) 268 269 /* Number of top N value histogram. */ 270 #define GCOV_TOPN_VALUES 4 271 272 /* Total number of single value counters. */ 273 #define GCOV_TOPN_VALUES_COUNTERS (2 * GCOV_TOPN_VALUES + 1) 274 275 /* Convert a counter index to a tag. */ 276 #define GCOV_TAG_FOR_COUNTER(COUNT) \ 277 (GCOV_TAG_COUNTER_BASE + ((gcov_unsigned_t)(COUNT) << 17)) 278 /* Convert a tag to a counter. */ 279 #define GCOV_COUNTER_FOR_TAG(TAG) \ 280 ((unsigned)(((TAG) - GCOV_TAG_COUNTER_BASE) >> 17)) 281 /* Check whether a tag is a counter tag. */ 282 #define GCOV_TAG_IS_COUNTER(TAG) \ 283 (!((TAG) & 0xFFFF) && GCOV_COUNTER_FOR_TAG (TAG) < GCOV_COUNTERS) 284 285 /* The tag level mask has 1's in the position of the inner levels, & 286 the lsb of the current level, and zero on the current and outer 287 levels. */ 288 #define GCOV_TAG_MASK(TAG) (((TAG) - 1) ^ (TAG)) 289 290 /* Return nonzero if SUB is an immediate subtag of TAG. */ 291 #define GCOV_TAG_IS_SUBTAG(TAG,SUB) \ 292 (GCOV_TAG_MASK (TAG) >> 8 == GCOV_TAG_MASK (SUB) \ 293 && !(((SUB) ^ (TAG)) & ~GCOV_TAG_MASK (TAG))) 294 295 /* Return nonzero if SUB is at a sublevel to TAG. */ 296 #define GCOV_TAG_IS_SUBLEVEL(TAG,SUB) \ 297 (GCOV_TAG_MASK (TAG) > GCOV_TAG_MASK (SUB)) 298 299 /* Basic block flags. */ 300 #define GCOV_BLOCK_UNEXPECTED (1 << 1) 301 302 /* Arc flags. */ 303 #define GCOV_ARC_ON_TREE (1 << 0) 304 #define GCOV_ARC_FAKE (1 << 1) 305 #define GCOV_ARC_FALLTHROUGH (1 << 2) 306 307 /* Object & program summary record. */ 308 309 struct gcov_summary 310 { 311 gcov_unsigned_t runs; /* Number of program runs. */ 312 gcov_type sum_max; /* Sum of individual run max values. */ 313 }; 314 315 #if !defined(inhibit_libc) 316 317 /* Functions for reading and writing gcov files. In libgcov you can 318 open the file for reading then writing. Elsewhere you can open the 319 file either for reading or for writing. When reading a file you may 320 use the gcov_read_* functions, gcov_sync, gcov_position, & 321 gcov_error. When writing a file you may use the gcov_write 322 functions, gcov_seek & gcov_error. When a file is to be rewritten 323 you use the functions for reading, then gcov_rewrite then the 324 functions for writing. Your file may become corrupted if you break 325 these invariants. */ 326 327 #if !IN_LIBGCOV 328 GCOV_LINKAGE int gcov_open (const char */*name*/, int /*direction*/); 329 #endif 330 331 #if !IN_LIBGCOV || defined (IN_GCOV_TOOL) 332 GCOV_LINKAGE int gcov_magic (gcov_unsigned_t, gcov_unsigned_t); 333 #endif 334 335 /* Available everywhere. */ 336 GCOV_LINKAGE int gcov_close (void) ATTRIBUTE_HIDDEN; 337 GCOV_LINKAGE gcov_unsigned_t gcov_read_unsigned (void) ATTRIBUTE_HIDDEN; 338 GCOV_LINKAGE gcov_type gcov_read_counter (void) ATTRIBUTE_HIDDEN; 339 GCOV_LINKAGE void gcov_read_summary (struct gcov_summary *) ATTRIBUTE_HIDDEN; 340 GCOV_LINKAGE const char *gcov_read_string (void); 341 GCOV_LINKAGE void gcov_sync (gcov_position_t /*base*/, 342 gcov_unsigned_t /*length */); 343 char *mangle_path (char const *base); 344 345 #if !IN_GCOV 346 /* Available outside gcov */ 347 GCOV_LINKAGE void gcov_write_unsigned (gcov_unsigned_t) ATTRIBUTE_HIDDEN; 348 #endif 349 350 #if !IN_GCOV && !IN_LIBGCOV 351 /* Available only in compiler */ 352 GCOV_LINKAGE void gcov_write_string (const char *); 353 GCOV_LINKAGE void gcov_write_filename (const char *); 354 GCOV_LINKAGE gcov_position_t gcov_write_tag (gcov_unsigned_t); 355 GCOV_LINKAGE void gcov_write_length (gcov_position_t /*position*/); 356 #endif 357 358 #if IN_GCOV > 0 359 /* Available in gcov */ 360 GCOV_LINKAGE time_t gcov_time (void); 361 #endif 362 363 #endif /* !inhibit_libc */ 364 365 #endif /* GCC_GCOV_IO_H */ 366