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
6This file is part of GCC.
7
8GCC is free software; you can redistribute it and/or modify it under
9the terms of the GNU General Public License as published by the Free
10Software Foundation; either version 3, or (at your option) any later
11version.
12
13GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14WARRANTY; without even the implied warranty of MERCHANTABILITY or
15FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16for more details.
17
18Under Section 7 of GPL version 3, you are granted additional
19permissions described in the GCC Runtime Library Exception, version
203.1, as published by the Free Software Foundation.
21
22You should have received a copy of the GNU General Public License and
23a copy of the GCC Runtime Library Exception along with this program;
24see 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
170typedef unsigned gcov_unsigned_t;
171typedef unsigned gcov_position_t;
172/* gcov_type is typedef'd elsewhere for the compiler */
173#if IN_GCOV
174#define GCOV_LINKAGE static
175typedef int64_t gcov_type;
176typedef 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_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) /* Obsolete */
241#define GCOV_TAG_PROGRAM_SUMMARY ((gcov_unsigned_t)0xa3000000)
242#define GCOV_TAG_SUMMARY_LENGTH(NUM) \
243 (1 + GCOV_COUNTERS_SUMMABLE * (10 + 3 * 2) + (NUM) * 5)
244#define GCOV_TAG_AFDO_FILE_NAMES ((gcov_unsigned_t)0xaa000000)
245#define GCOV_TAG_AFDO_FUNCTION ((gcov_unsigned_t)0xac000000)
246#define GCOV_TAG_AFDO_WORKING_SET ((gcov_unsigned_t)0xaf000000)
247
248
249/* Counters that are collected. */
250
251#define DEF_GCOV_COUNTER(COUNTER, NAME, MERGE_FN) COUNTER,
252enum {
253#include "gcov-counter.def"
254GCOV_COUNTERS
255};
256#undef DEF_GCOV_COUNTER
257
258/* Counters which can be summaried. */
259#define GCOV_COUNTERS_SUMMABLE (GCOV_COUNTER_ARCS + 1)
260
261/* The first of counters used for value profiling. They must form a
262 consecutive interval and their order must match the order of
263 HIST_TYPEs in value-prof.h. */
264#define GCOV_FIRST_VALUE_COUNTER GCOV_COUNTERS_SUMMABLE
265
266/* The last of counters used for value profiling. */
267#define GCOV_LAST_VALUE_COUNTER (GCOV_COUNTERS - 1)
268
269/* Number of counters used for value profiling. */
270#define GCOV_N_VALUE_COUNTERS \
271 (GCOV_LAST_VALUE_COUNTER - GCOV_FIRST_VALUE_COUNTER + 1)
272
273/* The number of hottest callees to be tracked. */
274#define GCOV_ICALL_TOPN_VAL 2
275
276/* The number of counter entries per icall callsite. */
277#define GCOV_ICALL_TOPN_NCOUNTS (1 + GCOV_ICALL_TOPN_VAL * 4)
278
279/* Convert a counter index to a tag. */
280#define GCOV_TAG_FOR_COUNTER(COUNT) \
281 (GCOV_TAG_COUNTER_BASE + ((gcov_unsigned_t)(COUNT) << 17))
282/* Convert a tag to a counter. */
283#define GCOV_COUNTER_FOR_TAG(TAG) \
284 ((unsigned)(((TAG) - GCOV_TAG_COUNTER_BASE) >> 17))
285/* Check whether a tag is a counter tag. */
286#define GCOV_TAG_IS_COUNTER(TAG) \
287 (!((TAG) & 0xFFFF) && GCOV_COUNTER_FOR_TAG (TAG) < GCOV_COUNTERS)
288
289/* The tag level mask has 1's in the position of the inner levels, &
290 the lsb of the current level, and zero on the current and outer
291 levels. */
292#define GCOV_TAG_MASK(TAG) (((TAG) - 1) ^ (TAG))
293
294/* Return nonzero if SUB is an immediate subtag of TAG. */
295#define GCOV_TAG_IS_SUBTAG(TAG,SUB) \
296 (GCOV_TAG_MASK (TAG) >> 8 == GCOV_TAG_MASK (SUB) \
297 && !(((SUB) ^ (TAG)) & ~GCOV_TAG_MASK (TAG)))
298
299/* Return nonzero if SUB is at a sublevel to TAG. */
300#define GCOV_TAG_IS_SUBLEVEL(TAG,SUB) \
301 (GCOV_TAG_MASK (TAG) > GCOV_TAG_MASK (SUB))
302
303/* Basic block flags. */
304#define GCOV_BLOCK_UNEXPECTED (1 << 1)
305
306/* Arc flags. */
307#define GCOV_ARC_ON_TREE (1 << 0)
308#define GCOV_ARC_FAKE (1 << 1)
309#define GCOV_ARC_FALLTHROUGH (1 << 2)
310
311/* Structured records. */
312
313/* Structure used for each bucket of the log2 histogram of counter values. */
314typedef struct
315{
316 /* Number of counters whose profile count falls within the bucket. */
317 gcov_unsigned_t num_counters;
318 /* Smallest profile count included in this bucket. */
319 gcov_type min_value;
320 /* Cumulative value of the profile counts in this bucket. */
321 gcov_type cum_value;
322} gcov_bucket_type;
323
324/* For a log2 scale histogram with each range split into 4
325 linear sub-ranges, there will be at most 64 (max gcov_type bit size) - 1 log2
326 ranges since the lowest 2 log2 values share the lowest 4 linear
327 sub-range (values 0 - 3). This is 252 total entries (63*4). */
328
329#define GCOV_HISTOGRAM_SIZE 252
330
331/* How many unsigned ints are required to hold a bit vector of non-zero
332 histogram entries when the histogram is written to the gcov file.
333 This is essentially a ceiling divide by 32 bits. */
334#define GCOV_HISTOGRAM_BITVECTOR_SIZE (GCOV_HISTOGRAM_SIZE + 31) / 32
335
336/* Cumulative counter data. */
337struct gcov_ctr_summary
338{
339 gcov_unsigned_t num; /* number of counters. */
340 gcov_unsigned_t runs; /* number of program runs */
341 gcov_type sum_all; /* sum of all counters accumulated. */
342 gcov_type run_max; /* maximum value on a single run. */
343 gcov_type sum_max; /* sum of individual run max values. */
344 gcov_bucket_type histogram[GCOV_HISTOGRAM_SIZE]; /* histogram of
345 counter values. */
346};
347
348/* Object & program summary record. */
349struct gcov_summary
350{
351 gcov_unsigned_t checksum; /* checksum of program */
352 struct gcov_ctr_summary ctrs[GCOV_COUNTERS_SUMMABLE];
353};
354
355#if !defined(inhibit_libc)
356
357/* Functions for reading and writing gcov files. In libgcov you can
358 open the file for reading then writing. Elsewhere you can open the
359 file either for reading or for writing. When reading a file you may
360 use the gcov_read_* functions, gcov_sync, gcov_position, &
361 gcov_error. When writing a file you may use the gcov_write
362 functions, gcov_seek & gcov_error. When a file is to be rewritten
363 you use the functions for reading, then gcov_rewrite then the
364 functions for writing. Your file may become corrupted if you break
365 these invariants. */
366
367#if !IN_LIBGCOV
368GCOV_LINKAGE int gcov_open (const char */*name*/, int /*direction*/);
369GCOV_LINKAGE int gcov_magic (gcov_unsigned_t, gcov_unsigned_t);
370#endif
371
372/* Available everywhere. */
373GCOV_LINKAGE int gcov_close (void) ATTRIBUTE_HIDDEN;
374GCOV_LINKAGE gcov_unsigned_t gcov_read_unsigned (void) ATTRIBUTE_HIDDEN;
375GCOV_LINKAGE gcov_type gcov_read_counter (void) ATTRIBUTE_HIDDEN;
376GCOV_LINKAGE void gcov_read_summary (struct gcov_summary *) ATTRIBUTE_HIDDEN;
377GCOV_LINKAGE const char *gcov_read_string (void);
378GCOV_LINKAGE void gcov_sync (gcov_position_t /*base*/,
379 gcov_unsigned_t /*length */);
380
381#if !IN_GCOV
382/* Available outside gcov */
383GCOV_LINKAGE void gcov_write_unsigned (gcov_unsigned_t) ATTRIBUTE_HIDDEN;
384#endif
385
386#if !IN_GCOV && !IN_LIBGCOV
387/* Available only in compiler */
388GCOV_LINKAGE unsigned gcov_histo_index (gcov_type value);
389GCOV_LINKAGE void gcov_write_string (const char *);
390GCOV_LINKAGE void gcov_write_filename (const char *);
391GCOV_LINKAGE gcov_position_t gcov_write_tag (gcov_unsigned_t);
392GCOV_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). */
405typedef 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
413GCOV_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 */
419GCOV_LINKAGE time_t gcov_time (void);
420#endif
421
422#endif /* !inhibit_libc */
423
424#endif /* GCC_GCOV_IO_H */
425