1 /* File format for coverage information
2 Copyright (C) 1996, 1997, 1998, 2000, 2002,
3 2003 Free Software Foundation, Inc.
4 Contributed by Bob Manson <manson@cygnus.com>.
5 Completely remangled by Nathan Sidwell <nathan@codesourcery.com>.
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify it under
10 the terms of the GNU General Public License as published by the Free
11 Software Foundation; either version 2, or (at your option) any later
14 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
15 WARRANTY; without even the implied warranty of MERCHANTABILITY or
16 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING. If not, write to the Free
21 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
24 /* As a special exception, if you link this library with other files,
25 some of which are compiled with GCC, to produce an executable,
26 this library does not by itself cause the resulting executable
27 to be covered by the GNU General Public License.
28 This exception does not however invalidate any other reasons why
29 the executable file might be covered by the GNU General Public License. */
31 /* Coverage information is held in two files. A basic block graph
32 file, which is generated by the compiler, and a counter file, which
33 is generated by the program under test. Both files use a similar
34 structure. We do not attempt to make these files backwards
35 compatible with previous versions, as you only need coverage
36 information when developing a program. We do hold version
37 information, so that mismatches can be detected, and we use a
38 format that allows tools to skip information they do not understand
39 or are not interested in.
41 Numbers are recorded in big endian unsigned binary form. Either in
42 32 or 64 bits. Strings are stored with a length count and NUL
43 terminator, and 0 to 3 bytes of zero padding up to the next 4 byte
44 boundary. Zero length and NULL strings are simply stored as a
45 length of zero (they have no trailing NUL or padding).
47 int32: byte3 byte2 byte1 byte0
48 int64: byte7 byte6 byte5 byte4 byte3 byte2 byte1 byte0
49 string: int32:0 | int32:length char* char:0 padding
50 padding: | char:0 | char:0 char:0 | char:0 char:0 char:0
51 item: int32 | int64 | string
53 The basic format of the files is
55 file : int32:magic int32:version record*
57 The magic ident is different for the bbg and the counter files.
58 The version is the same for both files and is derived from gcc's
59 version number. Although the ident and version are formally 32 bit
60 numbers, they are derived from 4 character ASCII strings. The
61 version number consists of the single character major version
62 number, a two character minor version number (leading zero for
63 versions less than 10), and a single character indicating the
64 status of the release. That will be 'e' experimental, 'p'
65 prerelease and 'r' for release. Because, by good fortune, these are
66 in alphabetical order, string collating can be used to compare
67 version strings, and because numbers are stored big endian, numeric
68 comparison can be used when it is read as a 32 bit value. Be aware
69 that the 'e' designation will (naturally) be unstable and might be
70 incompatible with itself. For gcc 3.4 experimental, it would be
71 '304e' (0x33303465). When the major version reaches 10, the letters
72 A-Z will be used. Assuming minor increments releases every 6
73 months, we have to make a major increment every 50 years. Assuming
74 major increments releases every 5 years, we're ok for the next 155
75 years -- good enough for me.
77 A record has a tag, length and variable amount of data.
80 header: int32:tag int32:length
83 Records are not nested, but there is a record hierarchy. Tag
84 numbers reflect this hierarchy. Tags are unique across bbg and da
85 files. Some record types have a varying amount of data. The LENGTH
86 is usually used to determine how much data. The tag value is split
87 into 4 8-bit fields, one for each of four possible levels. The
88 most significant is allocated first. Unused levels are zero.
89 Active levels are odd-valued, so that the LSB of the level is one.
90 A sub-level incorporates the values of its superlevels. This
91 formatting allows you to determine the tag heirarchy, without
92 understanding the tags themselves, and is similar to the standard
93 section numbering used in technical documents. Level values
94 [1..3f] are used for common tags, values [41..9f] for the graph
95 file and [a1..ff] for the counter file.
97 The basic block graph file contains the following records
98 bbg: unit function-graph*
99 unit: header int32:checksum string:source
100 function-graph: announce_function basic_blocks {arcs | lines}*
101 announce_function: header int32:ident int32:checksum
102 string:name string:source int32:lineno
103 basic_block: header int32:flags*
104 arcs: header int32:block_no arc*
105 arc: int32:dest_block int32:flags
106 lines: header int32:block_no line*
108 line: int32:line_no | int32:0 string:filename
110 The BASIC_BLOCK record holds per-bb flags. The number of blocks
111 can be inferred from its data length. There is one ARCS record per
112 basic block. The number of arcs from a bb is implicit from the
113 data length. It enumerates the destination bb and per-arc flags.
114 There is one LINES record per basic block, it enumerates the source
115 lines which belong to that basic block. Source file names are
116 introduced by a line number of 0, following lines are from the new
117 source file. The initial source file for the function is NULL, but
118 the current source file should be remembered from one LINES record
119 to the next. The end of a block is indicated by an empty filename
120 - this does not reset the current source file. Note there is no
121 ordering of the ARCS and LINES records: they may be in any order,
122 interleaved in any manner. The current filename follows the order
123 the LINES records are stored in the file, *not* the ordering of the
126 The data file contains the following records.
127 da: {unit function-data* summary:object summary:program*}*
128 unit: header int32:checksum
129 function-data: announce_function arc_counts
130 announce_function: header int32:ident int32:checksum
131 arc_counts: header int64:count*
132 summary: int32:checksum {count-summary}GCOV_COUNTERS
133 count-summary: int32:num int32:runs int64:sum
134 int64:max int64:sum_max
136 The ANNOUNCE_FUNCTION record is the same as that in the BBG file,
137 but without the source location.
138 The ARC_COUNTS gives the counter values for those arcs that are
139 instrumented. The SUMMARY records give information about the whole
140 object file and about the whole program. The checksum is used for
141 whole program summaries, and disambiguates different programs which
142 include the same instrumented object file. There may be several
143 program summaries, each with a unique checksum. The object
144 summary's checkum is zero. Note that the da file might contain
145 information from several runs concatenated, or the data might be
148 This file is included by both the compiler, gcov tools and the
149 runtime support library libgcov. IN_LIBGCOV and IN_GCOV are used to
150 distinguish which case is which. If IN_LIBGCOV is non-zero,
151 libgcov is being built. If IN_GCOV is non-zero, the gcov tools are
152 being built. Otherwise the compiler is being built. IN_GCOV may be
153 positive or negative. If positive, we are compiling a tool that
154 requires additional functions (see the code for knowledge of what
155 those functions are). */
157 #ifndef GCC_GCOV_IO_H
158 #define GCC_GCOV_IO_H
161 #if LONG_TYPE_SIZE == GCOV_TYPE_SIZE
162 typedef long gcov_type;
164 typedef long long gcov_type;
166 #if defined (TARGET_HAS_F_SETLKW)
167 #define GCOV_LOCKED 1
169 #define GCOV_LOCKED 0
171 #else /* !IN_LIBGCOV */
172 #if defined (HOST_HAS_F_SETLKW)
173 #define GCOV_LOCKED 1
175 #define GCOV_LOCKED 0
178 #define GCOV_LINKAGE static
179 typedef HOST_WIDEST_INT gcov_type;
181 #include <sys/types.h>
184 #endif /* !IN_LIBGCOV */
186 /* In gcov we want function linkage to be static, so we do not
187 polute the global namespace. In libgcov we need these functions
188 to be extern, so prefix them with __gcov so that we do not conflict.
189 In the compiler we want it extern, so that they can be accessed from
192 #define gcov_var __gcov_var
193 #define gcov_open __gcov_open
194 #define gcov_close __gcov_close
195 #define gcov_write_bytes __gcov_write_bytes
196 #define gcov_write_unsigned __gcov_write_unsigned
197 #define gcov_write_counter __gcov_write_counter
198 #pragma GCC poison gcov_write_string
199 #pragma GCC poison gcov_write_tag
200 #pragma GCC poison gcov_write_length
201 #define gcov_write_tag_length __gcov_write_tag_length
202 #define gcov_write_summary __gcov_write_summary
203 #define gcov_read_bytes __gcov_read_bytes
204 #define gcov_read_unsigned __gcov_read_unsigned
205 #define gcov_read_counter __gcov_read_counter
206 #pragma GCC poison gcov_read_string
207 #define gcov_read_summary __gcov_read_summary
208 #define gcov_position __gcov_position
209 #define gcov_sync __gcov_sync
210 #define gcov_seek __gcov_seek
211 #define gcov_rewrite __gcov_rewrite
212 #define gcov_is_eof __gcov_is_eof
213 #define gcov_is_error __gcov_is_error
214 #pragma GCC poison gcov_time
218 #define GCOV_LINKAGE extern
222 #define GCOV_DATA_SUFFIX ".da"
223 #define GCOV_GRAPH_SUFFIX ".bbg"
226 #define GCOV_DATA_MAGIC 0x67636f76 /* "gcov" */
227 #define GCOV_GRAPH_MAGIC 0x67626267 /* "gbbg" */
229 /* gcov-iov.h is automatically generated by the makefile from
230 version.c, it looks like
231 #define GCOV_VERSION ((unsigned)0x89abcdef)
233 #include "gcov-iov.h"
235 /* The record tags. Values [1..3f] are for tags which may be in either
236 file. Values [41..9f] for those in the bbg file and [a1..ff] for
239 #define GCOV_TAG_FUNCTION ((unsigned)0x01000000)
240 #define GCOV_TAG_FUNCTION_LENGTH (2 * 4)
241 #define GCOV_TAG_BLOCKS ((unsigned)0x01410000)
242 #define GCOV_TAG_BLOCKS_LENGTH(NUM) ((NUM) * 4)
243 #define GCOV_TAG_ARCS ((unsigned)0x01430000)
244 #define GCOV_TAG_ARCS_LENGTH(NUM) (1 * 4 + (NUM) * (2 * 4))
245 #define GCOV_TAG_LINES ((unsigned)0x01450000)
246 #define GCOV_TAG_COUNTER_BASE ((unsigned)0x01a10000) /* First counter */
247 #define GCOV_TAG_COUNTER_LENGTH(NUM) ((NUM) * 8)
248 #define GCOV_TAG_OBJECT_SUMMARY ((unsigned)0xa1000000)
249 #define GCOV_TAG_PROGRAM_SUMMARY ((unsigned)0xa3000000)
250 #define GCOV_TAG_SUMMARY_LENGTH (1 * 4 + GCOV_COUNTERS * (2 * 4 + 3 * 8))
252 /* Counters that are collected. */
253 #define GCOV_COUNTER_ARCS 0 /* Arc transitions. */
254 #define GCOV_COUNTERS 1
256 /* A list of human readable names of the counters */
257 #define GCOV_COUNTER_NAMES {"arcs"}
259 /* Names of merge functions for counters. */
260 #define GCOV_MERGE_FUNCTIONS {"__gcov_merge_add"}
262 /* Convert a counter index to a tag. */
263 #define GCOV_TAG_FOR_COUNTER(COUNT) \
264 (GCOV_TAG_COUNTER_BASE + ((COUNT) << 17))
265 /* Convert a tag to a counter. */
266 #define GCOV_COUNTER_FOR_TAG(TAG) \
267 (((TAG) - GCOV_TAG_COUNTER_BASE) >> 17)
268 /* Check whether a tag is a counter tag. */
269 #define GCOV_TAG_IS_COUNTER(TAG) \
270 (!((TAG) & 0xFFFF) && GCOV_COUNTER_FOR_TAG (TAG) < GCOV_COUNTERS)
272 /* The tag level mask has 1's in the position of the inner levels, &
273 the lsb of the current level, and zero on the current and outer
275 #define GCOV_TAG_MASK(TAG) (((TAG) - 1) ^ (TAG))
277 /* Return nonzero if SUB is an immediate subtag of TAG. */
278 #define GCOV_TAG_IS_SUBTAG(TAG,SUB) \
279 (GCOV_TAG_MASK (TAG) >> 8 == GCOV_TAG_MASK (SUB) \
280 && !(((SUB) ^ (TAG)) & ~GCOV_TAG_MASK(TAG)))
282 /* Return nonzero if SUB is at a sublevel to TAG. */
283 #define GCOV_TAG_IS_SUBLEVEL(TAG,SUB) \
284 (GCOV_TAG_MASK (TAG) > GCOV_TAG_MASK (SUB))
286 /* Basic block flags. */
287 #define GCOV_BLOCK_UNEXPECTED (1 << 1)
290 #define GCOV_ARC_ON_TREE (1 << 0)
291 #define GCOV_ARC_FAKE (1 << 1)
292 #define GCOV_ARC_FALLTHROUGH (1 << 2)
294 /* Structured records. */
296 /* Cumulative counter data. */
297 struct gcov_ctr_summary
299 unsigned num; /* number of counters. */
300 unsigned runs; /* number of program runs */
301 gcov_type sum_all; /* sum of all counters accumulated. */
302 gcov_type run_max; /* maximum value on a single run. */
303 gcov_type sum_max; /* sum of individual run max values. */
306 /* Object & program summary record. */
309 unsigned checksum; /* checksum of program */
310 struct gcov_ctr_summary ctrs[GCOV_COUNTERS];
313 /* Structures embedded in coveraged program. The structures generated
314 by write_profile must match these. */
317 /* Information about a single function. This uses the trailing array
318 idiom. The number of counters is determined from the counter_mask
319 in gcov_info. We hold an array of function info, so have to
320 explicitly calculate the correct array stride. */
323 unsigned ident; /* unique ident of function */
324 unsigned checksum; /* function checksum */
325 unsigned n_ctrs[0]; /* instrumented counters */
328 /* Type of function used to merge counters. */
329 typedef void (*gcov_merge_fn) (gcov_type *, unsigned);
331 /* Information about counters. */
334 unsigned num; /* number of counters. */
335 gcov_type *values; /* their values. */
336 gcov_merge_fn merge; /* The function used to merge them. */
339 /* Information about a single object file. */
342 unsigned long version; /* expected version number */
343 struct gcov_info *next; /* link to next, used by libgcc */
345 const char *filename; /* output file name */
347 unsigned n_functions; /* number of functions */
348 const struct gcov_fn_info *functions; /* table of functions */
350 unsigned ctr_mask; /* mask of counters instrumented. */
351 struct gcov_ctr_info counts[0]; /* count data. The number of bits
352 set in the ctr_mask field
353 determines how big this array
357 /* Register a new object file module. */
358 extern void __gcov_init (struct gcov_info *);
360 /* Called before fork, to avoid double counting. */
361 extern void __gcov_flush (void);
363 /* The merge function that just sums the counters. */
364 extern void __gcov_merge_add (gcov_type *, unsigned);
365 #endif /* IN_LIBGCOV */
369 /* Because small reads and writes, interspersed with seeks cause lots
370 of disk activity, we buffer the entire count files. */
372 GCOV_LINKAGE struct gcov_var
380 unsigned char *buffer;
383 /* Functions for reading and writing gcov files. */
384 GCOV_LINKAGE int gcov_open (const char */*name*/, int /*truncate*/);
385 GCOV_LINKAGE int gcov_close (void);
387 GCOV_LINKAGE unsigned char *gcov_write_bytes (unsigned);
388 GCOV_LINKAGE void gcov_write_unsigned (unsigned);
390 GCOV_LINKAGE void gcov_write_counter (gcov_type);
392 GCOV_LINKAGE void gcov_write_string (const char *);
395 GCOV_LINKAGE unsigned long gcov_write_tag (unsigned);
396 GCOV_LINKAGE void gcov_write_length (unsigned long /*position*/);
398 GCOV_LINKAGE void gcov_write_tag_length (unsigned, unsigned);
400 GCOV_LINKAGE void gcov_write_summary (unsigned, const struct gcov_summary *);
402 #endif /* !IN_GCOV */
403 GCOV_LINKAGE const unsigned char *gcov_read_bytes (unsigned);
404 GCOV_LINKAGE unsigned gcov_read_unsigned (void);
405 GCOV_LINKAGE gcov_type gcov_read_counter (void);
407 GCOV_LINKAGE const char *gcov_read_string (void);
409 GCOV_LINKAGE void gcov_read_summary (struct gcov_summary *);
410 static unsigned long gcov_position (void);
411 static void gcov_sync (unsigned long /*base*/, unsigned /*length */);
412 static void gcov_seek (unsigned long /*position*/);
413 static void gcov_rewrite (void);
414 static int gcov_is_eof (void);
415 static int gcov_is_error (void);
417 GCOV_LINKAGE time_t gcov_time (void);
420 /* Save the current position in the gcov file. */
422 static inline unsigned long
425 return gcov_var.position;
428 /* Reset to a known position. BASE should have been obtained from
429 gcov_save_position, LENGTH should be a record length, or zero. */
432 gcov_sync (unsigned long base, unsigned length)
437 if (gcov_var.length < base)
440 base = gcov_var.length;
442 gcov_var.position = base;
446 /* Move to the end of the gcov file. */
449 gcov_seek (unsigned long base)
451 gcov_var.position = base < gcov_var.length ? base : gcov_var.length;
454 /* Move to beginning of file and intialize for writing. */
459 gcov_var.position = 0;
462 /* Tests whether we have reached end of .da file. */
467 return gcov_var.position == gcov_var.length;
470 /* Return non-zero if the error flag is set. */
475 return gcov_var.file ? gcov_var.error : 1;
478 #endif /* IN_LIBGCOV >= 0 */
480 #endif /* GCC_GCOV_IO_H */