1 /* File format for coverage information
2 Copyright (C) 1996, 1997, 1998, 2000, 2002 Free Software Foundation, Inc.
3 Contributed by Bob Manson <manson@cygnus.com>.
4 Completely remangled by Nathan Sidwell <nathan@codesourcery.com>.
6 This file is part of GCC.
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 2, or (at your option) any later
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
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING. If not, write to the Free
20 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
23 /* Coverage information is held in two files. A basic block graph
24 file, which is generated by the compiler, and a counter file, which
25 is generated by the program under test. Both files use a similar
26 structure. We do not attempt to make these files backwards
27 compatible with previous versions, as you only need coverage
28 information when developing a program. We do hold version
29 information, so that mismatches can be detected, and we use a
30 format that allows tools to skip information they do not understand
31 or are not interested in.
33 Numbers are recorded in big endian unsigned binary form. Either in
34 32 or 64 bits. Strings are stored with a length count and NUL
35 terminator, and 0 to 3 bytes of zero padding up to the next 4 byte
36 boundary. Zero length and NULL strings are simply stored as a
37 length of zero (they have no trailing NUL or padding).
39 int32: byte3 byte2 byte1 byte0
40 int64: byte7 byte6 byte5 byte4 byte3 byte2 byte1 byte0
41 string: int32:0 | int32:length char* char:0 padding
42 padding: | char:0 | char:0 char:0 | char:0 char:0 char:0
43 item: int32 | int64 | string
45 The basic format of the files is
47 file : int32:magic int32:version record*
49 The magic ident is different for the bbg and the counter files.
50 The version is the same for both files and is derived from gcc's
51 version number. Although the ident and version are formally 32 bit
52 numbers, they are derived from 4 character ASCII strings. The
53 version number consists of the single character major version
54 number, a two character minor version number (leading zero for
55 versions less than 10), and a single character indicating the
56 status of the release. That will be 'e' experimental, 'p'
57 prerelease and 'r' for release. Because, by good fortune, these are
58 in alphabetical order, string collating can be used to compare
59 version strings, and because numbers are stored big endian, numeric
60 comparison can be used when it is read as a 32 bit value. Be aware
61 that the 'e' designation will (naturally) be unstable and might be
62 incompatible with itself. For gcc 3.4 experimental, it would be
63 '304e' (0x33303465). When the major version reaches 10, the letters
64 A-Z will be used. Assuming minor increments releases every 6
65 months, we have to make a major increment every 50 years. Assuming
66 major increments releases every 5 years, we're ok for the next 155
67 years -- good enough for me.
69 A record has a tag, length and variable amount of data.
72 header: int32:tag int32:length
75 Records are not nested, but there is a record hierarchy. Tag
76 numbers reflect this hierarchy. Tags are unique across bbg and da
77 files. Some record types have a varying amount of data. The LENGTH
78 is usually used to determine how much data. The tag value is split
79 into 4 8-bit fields, one for each of four possible levels. The
80 most significant is allocated first. Unused levels are zero.
81 Active levels are odd-valued, so that the LSB of the level is one.
82 A sub-level incorporates the values of its superlevels. This
83 formatting allows you to determine the tag heirarchy, without
84 understanding the tags themselves, and is similar to the standard
85 section numbering used in technical documents. Level values
86 [1..3f] are used for common tags, values [41..9f] for the graph
87 file and [a1..ff] for the counter file.
89 The basic block graph file contains the following records
91 function-graph: announce_function basic_blocks {arcs | lines}*
92 announce_function: header string:name int32:checksum
93 basic_block: header int32:flags*
94 arcs: header int32:block_no arc*
95 arc: int32:dest_block int32:flags
96 lines: header int32:block_no line*
98 line: int32:line_no | int32:0 string:filename
100 The BASIC_BLOCK record holds per-bb flags. The number of blocks
101 can be inferred from its data length. There is one ARCS record per
102 basic block. The number of arcs from a bb is implicit from the
103 data length. It enumerates the destination bb and per-arc flags.
104 There is one LINES record per basic block, it enumerates the source
105 lines which belong to that basic block. Source file names are
106 introduced by a line number of 0, following lines are from the new
107 source file. The initial source file for the function is NULL, but
108 the current source file should be remembered from one LINES record
109 to the next. The end of a block is indicated by an empty filename
110 - this does not reset the current source file. Note there is no
111 ordering of the ARCS and LINES records: they may be in any order,
112 interleaved in any manner. The current filename follows the order
113 the LINES records are stored in the file, *not* the ordering of the
116 The data file contains the following records.
117 da: {function-data* summary:object summary:program*}*
118 function-data: announce_function arc_counts
119 announce_function: header string:name int32:checksum
120 arc_counts: header int64:count*
121 summary: in32:checksum int32:runs int32:arcs int64:sum int64:max \
122 int64:max_sum int64:sum_max
124 The ANNOUNCE_FUNCTION record is the same as that in the BBG file.
125 The ARC_COUNTS gives the counter values for those arcs that are
126 instrumented. The SUMMARY records give information about the whole
127 object file and about the whole program. The checksum is used for
128 whole program summaries, and disambiguates different programs which
129 include the same instrumented object file. There may be several
130 program summaries, each with a unique checksum. The object
131 summary's checkum is zero. Note that the da file might contain
132 information from several runs concatenated, or the data might be
135 This file is included by both the compiler, gcov tools and the
136 library. The IN_LIBGCC2 define distinguishes these cases. When
137 IN_LIBGCC2 is nonzero, we're building libgcc2 for the target and
138 know the compiler is (the just built) gcc. Otherwise we're
139 generating code for the host, and the compiler may or may not be
140 gcc. In this latter case, you must ensure that 'gcov_type' is
141 typedefed to something suitable (unsigned HOST_WIDEST_INT is
142 usually what you want). */
144 #ifndef GCC_GCOV_IO_H
145 #define GCC_GCOV_IO_H
148 #if LONG_TYPE_SIZE == GCOV_TYPE_SIZE
149 typedef long gcov_type
;
151 typedef long long gcov_type
;
153 #endif /* IN_LIBGCC2 */
156 #define GCOV_DATA_SUFFIX ".da"
157 #define GCOV_GRAPH_SUFFIX ".bbg"
160 #define GCOV_DATA_MAGIC 0x67636f76 /* "gcov" */
161 #define GCOV_GRAPH_MAGIC 0x67626267 /* "gbbg" */
163 /* gcov-iov.h is automatically generated by the makefile from
164 version.c, it looks like
165 #define GCOV_VERSION ((unsigned)0x89abcdef)
167 #include "gcov-iov.h"
169 /* The record tags. Values [1..3f] are for tags which may be in either
170 file. Values [41..9f] for those in the bbg file and [a1..ff] for
173 #define GCOV_TAG_FUNCTION ((unsigned)0x01000000)
174 #define GCOV_TAG_BLOCKS ((unsigned)0x01410000)
175 #define GCOV_TAG_ARCS ((unsigned)0x01430000)
176 #define GCOV_TAG_LINES ((unsigned)0x01450000)
177 #define GCOV_TAG_ARC_COUNTS ((unsigned)0x01a10000)
178 #define GCOV_TAG_OBJECT_SUMMARY ((unsigned)0xa1000000)
179 #define GCOV_TAG_PROGRAM_SUMMARY ((unsigned)0xa3000000)
180 #define GCOV_TAG_PLACEHOLDER_SUMMARY ((unsigned)0xa5000000)
181 #define GCOV_TAG_INCORRECT_SUMMARY ((unsigned)0xa7000000)
183 /* The tag level mask has 1's in the position of the inner levels, &
184 the lsb of the current level, and zero on the current and outer
186 #define GCOV_TAG_MASK(TAG) (((TAG) - 1) ^ (TAG))
188 /* Return nonzero if SUB is an immediate subtag of TAG. */
189 #define GCOV_TAG_IS_SUBTAG(TAG,SUB) \
190 (GCOV_TAG_MASK (TAG) >> 8 == GCOV_TAG_MASK (SUB) \
191 && !(((SUB) ^ (TAG)) & ~GCOV_TAG_MASK(TAG)))
193 /* Return nonzero if SUB is at a sublevel to TAG. */
194 #define GCOV_TAG_IS_SUBLEVEL(TAG,SUB) \
195 (GCOV_TAG_MASK (TAG) > GCOV_TAG_MASK (SUB))
197 /* Basic block flags. */
198 #define GCOV_BLOCK_UNEXPECTED (1 << 0)
201 #define GCOV_ARC_ON_TREE (1 << 0)
202 #define GCOV_ARC_FAKE (1 << 1)
203 #define GCOV_ARC_FALLTHROUGH (1 << 2)
205 /* Structured records. */
207 /* Object & program summary record. */
210 unsigned checksum
; /* checksum of program */
211 unsigned runs
; /* number of program runs */
212 unsigned arcs
; /* number of instrumented arcs */
213 gcov_type arc_sum
; /* sum of all arc counters */
214 gcov_type arc_max_one
; /* max counter on any one run */
215 gcov_type arc_max_sum
; /* maximum arc_sum */
216 gcov_type arc_sum_max
; /* sum of max_one */
219 /* Structures embedded in coveraged program. The structures generated
220 by write_profile must match these. */
222 /* Information about section of counters for a function. */
223 struct counter_section
225 unsigned tag
; /* Tag of the section. */
226 unsigned n_counters
; /* Number of counters in the section. */
230 /* Information about section of counters for an object file. */
231 struct counter_section_data
233 unsigned tag
; /* Tag of the section. */
234 unsigned n_counters
; /* Number of counters in the section. */
235 gcov_type
*counters
; /* The data. */
238 /* Information about a single function. */
241 const char *name
; /* (mangled) name of function */
242 unsigned checksum
; /* function checksum */
243 unsigned n_counter_sections
; /* Number of types of counters */
244 const struct counter_section
*counter_sections
;
245 /* The section descriptions */
248 /* Information about a single object file. */
251 unsigned long version
; /* expected version number */
252 struct gcov_info
*next
; /* link to next, used by libgcc */
254 const char *filename
; /* output file name */
255 long wkspc
; /* libgcc workspace */
257 unsigned n_functions
; /* number of functions */
258 const struct function_info
*functions
; /* table of functions */
260 unsigned n_counter_sections
; /* Number of types of counters */
261 const struct counter_section_data
*counter_sections
;
262 /* The data to be put into the sections. */
265 /* Register a new object file module. */
266 extern void __gcov_init (struct gcov_info
*);
268 /* Called before fork, to avoid double counting. */
269 extern void __gcov_flush (void);
271 /* Since this file is used in both host and target files, and we don't
272 include ansidecl.h in target files, provide some necessary macros. */
276 #ifndef ATTRIBUTE_UNUSED
277 # define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
280 #endif /* IN_LIBGCC2 */
282 /* Functions for reading and writing gcov files. */
283 static int gcov_write_unsigned
PARAMS((FILE *, unsigned))
285 static int gcov_write_counter
PARAMS((FILE *, gcov_type
))
287 static int gcov_write_string
PARAMS((FILE *, const char *, unsigned))
289 static int gcov_read_unsigned
PARAMS((FILE *, unsigned *))
291 static int gcov_read_counter
PARAMS((FILE *, gcov_type
*))
294 static int gcov_read_string
PARAMS((FILE *, char **, unsigned *))
297 static int gcov_read_summary
PARAMS ((FILE *, struct gcov_summary
*))
300 static int gcov_write_summary
PARAMS ((FILE *, unsigned,
301 const struct gcov_summary
*))
304 #define gcov_save_position(STREAM) \
306 #define gcov_reserve_length(STREAM) \
307 (gcov_write_unsigned (STREAM, 0) ? 0 : ftell (STREAM) - 4)
308 static int gcov_write_length
PARAMS((FILE *, long))
310 #define gcov_resync(STREAM, BASE, LENGTH) \
311 fseek (STREAM, BASE + (long)LENGTH, SEEK_SET)
312 #define gcov_skip(STREAM, LENGTH) \
313 fseek (STREAM, LENGTH, SEEK_CUR)
314 #define gcov_skip_string(STREAM, LENGTH) \
315 fseek (STREAM, (LENGTH) + 4 - ((LENGTH) & 3), SEEK_CUR)
318 /* Write VALUE to coverage file FILE. Return nonzero if failed due to
319 file i/o error, or value error. */
322 gcov_write_unsigned (file
, value
)
329 for (ix
= sizeof (buffer
); ix
--; )
334 return ((sizeof (value
) > sizeof (buffer
) && value
)
335 || fwrite (buffer
, sizeof (buffer
), 1, file
) != 1);
338 /* Write VALUE to coverage file FILE. Return nonzero if failed due to
339 file i/o error, or value error. Negative values are not checked
340 here -- they are checked in gcov_read_counter. */
343 gcov_write_counter (file
, value
)
350 for (ix
= sizeof (buffer
); ix
--; )
355 return ((sizeof (value
) > sizeof (buffer
) && value
!= 0 && value
!= -1)
356 || fwrite (buffer
, sizeof (buffer
), 1, file
) != 1);
359 /* Write VALUE to coverage file FILE. Return nonzero if failed due to
360 file i/o error, or value error. */
363 gcov_write_string (file
, string
, length
)
371 return (gcov_write_unsigned (file
, length
)
372 || fwrite (string
, length
, 1, file
) != 1
373 || fwrite (&pad
, 4 - (length
& 3), 1, file
) != 1);
375 return gcov_write_unsigned (file
, 0);
378 /* Read *VALUE_P from coverage file FILE. Return nonzero if failed
379 due to file i/o error, or range error. */
382 gcov_read_unsigned (file
, value_p
)
388 unsigned char buffer
[4];
390 if (fread (buffer
, sizeof (buffer
), 1, file
) != 1)
392 for (ix
= sizeof (value
); ix
< sizeof (buffer
); ix
++)
395 for (ix
= 0; ix
!= sizeof (buffer
); ix
++)
404 /* Read *VALUE_P from coverage file FILE. Return nonzero if failed
405 due to file i/o error, or range error. */
408 gcov_read_counter (file
, value_p
)
414 unsigned char buffer
[8];
416 if (fread (buffer
, sizeof (buffer
), 1, file
) != 1)
418 for (ix
= sizeof (value
); ix
< sizeof (buffer
); ix
++)
421 for (ix
= 0; ix
!= sizeof (buffer
); ix
++)
433 /* Read string from coverage file FILE. Length is stored in *LENGTH_P
434 (if non-null), a buffer is allocated and returned in *STRING_P.
435 Return nonzero if failed due to file i/o error, or range
436 error. Uses xmalloc to allocate the string buffer. */
439 gcov_read_string (file
, string_p
, length_p
)
446 if (gcov_read_unsigned (file
, &length
))
457 length
+= 4 - (length
& 3);
458 *string_p
= (char *) xmalloc (length
);
460 return fread (*string_p
, length
, 1, file
) != 1;
464 #endif /* !IN_LIBGCC2 */
466 /* Write a record length at PLACE. The current file position is the
467 end of the record, and is restored before returning. Returns
468 nonzero on failure. */
471 gcov_write_length (file
, place
)
475 long here
= ftell (file
);
476 int result
= (!place
|| fseek (file
, place
, SEEK_SET
)
477 || gcov_write_unsigned (file
, here
- place
- 4));
478 if (fseek (file
, here
, SEEK_SET
))
483 #define GCOV_SUMMARY_LENGTH 44
485 gcov_read_summary (da_file
, summary
)
487 struct gcov_summary
*summary
;
489 return (gcov_read_unsigned (da_file
, &summary
->checksum
)
490 || gcov_read_unsigned (da_file
, &summary
->runs
)
491 || gcov_read_unsigned (da_file
, &summary
->arcs
)
492 || gcov_read_counter (da_file
, &summary
->arc_sum
)
493 || gcov_read_counter (da_file
, &summary
->arc_max_one
)
494 || gcov_read_counter (da_file
, &summary
->arc_max_sum
)
495 || gcov_read_counter (da_file
, &summary
->arc_sum_max
));
500 gcov_write_summary (da_file
, tag
, summary
)
503 const struct gcov_summary
*summary
;
507 return (gcov_write_unsigned (da_file
, tag
)
508 || !(base
= gcov_reserve_length (da_file
))
509 || gcov_write_unsigned (da_file
, summary
->checksum
)
510 || gcov_write_unsigned (da_file
, summary
->runs
)
511 || gcov_write_unsigned (da_file
, summary
->arcs
)
512 || gcov_write_counter (da_file
, summary
->arc_sum
)
513 || gcov_write_counter (da_file
, summary
->arc_max_one
)
514 || gcov_write_counter (da_file
, summary
->arc_max_sum
)
515 || gcov_write_counter (da_file
, summary
->arc_sum_max
)
516 || gcov_write_length (da_file
, base
));
520 #endif /* GCC_GCOV_IO_H */