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.\" ========================================================================
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.\"
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.IX Title "GCOV 1"
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.TH GCOV 1 "2004-11-05" "gcc-3.4.3" "GNU"
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.SH "NAME"
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gcov \- coverage testing tool
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.SH "SYNOPSIS"
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136 |
.IX Header "SYNOPSIS"
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gcov [\fB\-v\fR|\fB\-\-version\fR] [\fB\-h\fR|\fB\-\-help\fR]
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[\fB\-a\fR|\fB\-\-all\-blocks\fR]
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139 |
[\fB\-b\fR|\fB\-\-branch\-probabilities\fR]
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|
140 |
[\fB\-c\fR|\fB\-\-branch\-counts\fR]
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|
141 |
[\fB\-n\fR|\fB\-\-no\-output\fR]
|
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142 |
[\fB\-l\fR|\fB\-\-long\-file\-names\fR]
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143 |
[\fB\-p\fR|\fB\-\-preserve\-paths\fR]
|
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144 |
[\fB\-f\fR|\fB\-\-function\-summaries\fR]
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[\fB\-o\fR|\fB\-\-object\-directory\fR \fIdirectory|file\fR] \fIsourcefile\fR
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[\fB\-u\fR|\fB\-\-unconditional\-branches\fR]
|
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.SH "DESCRIPTION"
|
|
148 |
.IX Header "DESCRIPTION"
|
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149 |
\&\fBgcov\fR is a test coverage program. Use it in concert with \s-1GCC\s0
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to analyze your programs to help create more efficient, faster running
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code and to discover untested parts of your program. You can use
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152 |
\&\fBgcov\fR as a profiling tool to help discover where your
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153 |
optimization efforts will best affect your code. You can also use
|
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154 |
\&\fBgcov\fR along with the other profiling tool, \fBgprof\fR, to
|
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155 |
assess which parts of your code use the greatest amount of computing
|
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156 |
time.
|
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157 |
.PP
|
|
158 |
Profiling tools help you analyze your code's performance. Using a
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159 |
profiler such as \fBgcov\fR or \fBgprof\fR, you can find out some
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|
160 |
basic performance statistics, such as:
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.IP "\(bu" 4
|
|
162 |
how often each line of code executes
|
|
163 |
.IP "\(bu" 4
|
|
164 |
what lines of code are actually executed
|
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165 |
.IP "\(bu" 4
|
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166 |
how much computing time each section of code uses
|
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.PP
|
|
168 |
Once you know these things about how your code works when compiled, you
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can look at each module to see which modules should be optimized.
|
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\&\fBgcov\fR helps you determine where to work on optimization.
|
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171 |
.PP
|
|
172 |
Software developers also use coverage testing in concert with
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testsuites, to make sure software is actually good enough for a release.
|
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174 |
Testsuites can verify that a program works as expected; a coverage
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175 |
program tests to see how much of the program is exercised by the
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testsuite. Developers can then determine what kinds of test cases need
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to be added to the testsuites to create both better testing and a better
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final product.
|
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.PP
|
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180 |
You should compile your code without optimization if you plan to use
|
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181 |
\&\fBgcov\fR because the optimization, by combining some lines of code
|
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182 |
into one function, may not give you as much information as you need to
|
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look for `hot spots' where the code is using a great deal of computer
|
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184 |
time. Likewise, because \fBgcov\fR accumulates statistics by line (at
|
|
185 |
the lowest resolution), it works best with a programming style that
|
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places only one statement on each line. If you use complicated macros
|
|
187 |
that expand to loops or to other control structures, the statistics are
|
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188 |
less helpful\-\-\-they only report on the line where the macro call
|
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189 |
appears. If your complex macros behave like functions, you can replace
|
|
190 |
them with inline functions to solve this problem.
|
|
191 |
.PP
|
|
192 |
\&\fBgcov\fR creates a logfile called \fI\fIsourcefile\fI.gcov\fR which
|
|
193 |
indicates how many times each line of a source file \fI\fIsourcefile\fI.c\fR
|
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194 |
has executed. You can use these logfiles along with \fBgprof\fR to aid
|
|
195 |
in fine-tuning the performance of your programs. \fBgprof\fR gives
|
|
196 |
timing information you can use along with the information you get from
|
|
197 |
\&\fBgcov\fR.
|
|
198 |
.PP
|
|
199 |
\&\fBgcov\fR works only on code compiled with \s-1GCC\s0. It is not
|
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200 |
compatible with any other profiling or test coverage mechanism.
|
|
201 |
.SH "OPTIONS"
|
|
202 |
.IX Header "OPTIONS"
|
|
203 |
.IP "\fB\-h\fR" 4
|
|
204 |
.IX Item "-h"
|
|
205 |
.PD 0
|
|
206 |
.IP "\fB\-\-help\fR" 4
|
|
207 |
.IX Item "--help"
|
|
208 |
.PD
|
|
209 |
Display help about using \fBgcov\fR (on the standard output), and
|
|
210 |
exit without doing any further processing.
|
|
211 |
.IP "\fB\-v\fR" 4
|
|
212 |
.IX Item "-v"
|
|
213 |
.PD 0
|
|
214 |
.IP "\fB\-\-version\fR" 4
|
|
215 |
.IX Item "--version"
|
|
216 |
.PD
|
|
217 |
Display the \fBgcov\fR version number (on the standard output),
|
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and exit without doing any further processing.
|
|
219 |
.IP "\fB\-a\fR" 4
|
|
220 |
.IX Item "-a"
|
|
221 |
.PD 0
|
|
222 |
.IP "\fB\-\-all\-blocks\fR" 4
|
|
223 |
.IX Item "--all-blocks"
|
|
224 |
.PD
|
|
225 |
Write individual execution counts for every basic block. Normally gcov
|
|
226 |
outputs execution counts only for the main blocks of a line. With this
|
|
227 |
option you can determine if blocks within a single line are not being
|
|
228 |
executed.
|
|
229 |
.IP "\fB\-b\fR" 4
|
|
230 |
.IX Item "-b"
|
|
231 |
.PD 0
|
|
232 |
.IP "\fB\-\-branch\-probabilities\fR" 4
|
|
233 |
.IX Item "--branch-probabilities"
|
|
234 |
.PD
|
|
235 |
Write branch frequencies to the output file, and write branch summary
|
|
236 |
info to the standard output. This option allows you to see how often
|
|
237 |
each branch in your program was taken. Unconditional branches will not
|
|
238 |
be shown, unless the \fB\-u\fR option is given.
|
|
239 |
.IP "\fB\-c\fR" 4
|
|
240 |
.IX Item "-c"
|
|
241 |
.PD 0
|
|
242 |
.IP "\fB\-\-branch\-counts\fR" 4
|
|
243 |
.IX Item "--branch-counts"
|
|
244 |
.PD
|
|
245 |
Write branch frequencies as the number of branches taken, rather than
|
|
246 |
the percentage of branches taken.
|
|
247 |
.IP "\fB\-n\fR" 4
|
|
248 |
.IX Item "-n"
|
|
249 |
.PD 0
|
|
250 |
.IP "\fB\-\-no\-output\fR" 4
|
|
251 |
.IX Item "--no-output"
|
|
252 |
.PD
|
|
253 |
Do not create the \fBgcov\fR output file.
|
|
254 |
.IP "\fB\-l\fR" 4
|
|
255 |
.IX Item "-l"
|
|
256 |
.PD 0
|
|
257 |
.IP "\fB\-\-long\-file\-names\fR" 4
|
|
258 |
.IX Item "--long-file-names"
|
|
259 |
.PD
|
|
260 |
Create long file names for included source files. For example, if the
|
|
261 |
header file \fIx.h\fR contains code, and was included in the file
|
|
262 |
\&\fIa.c\fR, then running \fBgcov\fR on the file \fIa.c\fR will produce
|
|
263 |
an output file called \fIa.c##x.h.gcov\fR instead of \fIx.h.gcov\fR.
|
|
264 |
This can be useful if \fIx.h\fR is included in multiple source
|
|
265 |
files. If you uses the \fB\-p\fR option, both the including and
|
|
266 |
included file names will be complete path names.
|
|
267 |
.IP "\fB\-p\fR" 4
|
|
268 |
.IX Item "-p"
|
|
269 |
.PD 0
|
|
270 |
.IP "\fB\-\-preserve\-paths\fR" 4
|
|
271 |
.IX Item "--preserve-paths"
|
|
272 |
.PD
|
|
273 |
Preserve complete path information in the names of generated
|
|
274 |
\&\fI.gcov\fR files. Without this option, just the filename component is
|
|
275 |
used. With this option, all directories are used, with '/' characters
|
|
276 |
translated to '#' characters, '.' directory components removed and '..'
|
|
277 |
components renamed to '^'. This is useful if sourcefiles are in several
|
|
278 |
different directories. It also affects the \fB\-l\fR option.
|
|
279 |
.IP "\fB\-f\fR" 4
|
|
280 |
.IX Item "-f"
|
|
281 |
.PD 0
|
|
282 |
.IP "\fB\-\-function\-summaries\fR" 4
|
|
283 |
.IX Item "--function-summaries"
|
|
284 |
.PD
|
|
285 |
Output summaries for each function in addition to the file level summary.
|
|
286 |
.IP "\fB\-o\fR \fIdirectory|file\fR" 4
|
|
287 |
.IX Item "-o directory|file"
|
|
288 |
.PD 0
|
|
289 |
.IP "\fB\-\-object\-directory\fR \fIdirectory\fR" 4
|
|
290 |
.IX Item "--object-directory directory"
|
|
291 |
.IP "\fB\-\-object\-file\fR \fIfile\fR" 4
|
|
292 |
.IX Item "--object-file file"
|
|
293 |
.PD
|
|
294 |
Specify either the directory containing the gcov data files, or the
|
|
295 |
object path name. The \fI.gcno\fR, and
|
|
296 |
\&\fI.gcda\fR data files are searched for using this option. If a directory
|
|
297 |
is specified, the data files are in that directory and named after the
|
|
298 |
source file name, without its extension. If a file is specified here,
|
|
299 |
the data files are named after that file, without its extension. If this
|
|
300 |
option is not supplied, it defaults to the current directory.
|
|
301 |
.IP "\fB\-u\fR" 4
|
|
302 |
.IX Item "-u"
|
|
303 |
.PD 0
|
|
304 |
.IP "\fB\-\-unconditional\-branches\fR" 4
|
|
305 |
.IX Item "--unconditional-branches"
|
|
306 |
.PD
|
|
307 |
When branch counts are given, include those of unconditional branches.
|
|
308 |
Unconditional branches are normally not interesting.
|
|
309 |
.PP
|
|
310 |
\&\fBgcov\fR should be run with the current directory the same as that
|
|
311 |
when you invoked the compiler. Otherwise it will not be able to locate
|
|
312 |
the source files. \fBgcov\fR produces files called
|
|
313 |
\&\fI\fImangledname\fI.gcov\fR in the current directory. These contain
|
|
314 |
the coverage information of the source file they correspond to.
|
|
315 |
One \fI.gcov\fR file is produced for each source file containing code,
|
|
316 |
which was compiled to produce the data files. The \fImangledname\fR part
|
|
317 |
of the output file name is usually simply the source file name, but can
|
|
318 |
be something more complicated if the \fB\-l\fR or \fB\-p\fR options are
|
|
319 |
given. Refer to those options for details.
|
|
320 |
.PP
|
|
321 |
The \fI.gcov\fR files contain the ':' separated fields along with
|
|
322 |
program source code. The format is
|
|
323 |
.PP
|
|
324 |
.Vb 1
|
|
325 |
\& <execution_count>:<line_number>:<source line text>
|
|
326 |
.Ve
|
|
327 |
.PP
|
|
328 |
Additional block information may succeed each line, when requested by
|
|
329 |
command line option. The \fIexecution_count\fR is \fB\-\fR for lines
|
|
330 |
containing no code and \fB#####\fR for lines which were never
|
|
331 |
executed. Some lines of information at the start have \fIline_number\fR
|
|
332 |
of zero.
|
|
333 |
.PP
|
|
334 |
When printing percentages, 0% and 100% are only printed when the values
|
|
335 |
are \fIexactly\fR 0% and 100% respectively. Other values which would
|
|
336 |
conventionally be rounded to 0% or 100% are instead printed as the
|
|
337 |
nearest non-boundary value.
|
|
338 |
.PP
|
|
339 |
When using \fBgcov\fR, you must first compile your program with two
|
|
340 |
special \s-1GCC\s0 options: \fB\-fprofile\-arcs \-ftest\-coverage\fR.
|
|
341 |
This tells the compiler to generate additional information needed by
|
|
342 |
gcov (basically a flow graph of the program) and also includes
|
|
343 |
additional code in the object files for generating the extra profiling
|
|
344 |
information needed by gcov. These additional files are placed in the
|
|
345 |
directory where the object file is located.
|
|
346 |
.PP
|
|
347 |
Running the program will cause profile output to be generated. For each
|
|
348 |
source file compiled with \fB\-fprofile\-arcs\fR, an accompanying
|
|
349 |
\&\fI.gcda\fR file will be placed in the object file directory.
|
|
350 |
.PP
|
|
351 |
Running \fBgcov\fR with your program's source file names as arguments
|
|
352 |
will now produce a listing of the code along with frequency of execution
|
|
353 |
for each line. For example, if your program is called \fItmp.c\fR, this
|
|
354 |
is what you see when you use the basic \fBgcov\fR facility:
|
|
355 |
.PP
|
|
356 |
.Vb 5
|
|
357 |
\& $ gcc -fprofile-arcs -ftest-coverage tmp.c
|
|
358 |
\& $ a.out
|
|
359 |
\& $ gcov tmp.c
|
|
360 |
\& 90.00% of 10 source lines executed in file tmp.c
|
|
361 |
\& Creating tmp.c.gcov.
|
|
362 |
.Ve
|
|
363 |
.PP
|
|
364 |
The file \fItmp.c.gcov\fR contains output from \fBgcov\fR.
|
|
365 |
Here is a sample:
|
|
366 |
.PP
|
|
367 |
.Vb 23
|
|
368 |
\& -: 0:Source:tmp.c
|
|
369 |
\& -: 0:Graph:tmp.gcno
|
|
370 |
\& -: 0:Data:tmp.gcda
|
|
371 |
\& -: 0:Runs:1
|
|
372 |
\& -: 0:Programs:1
|
|
373 |
\& -: 1:#include <stdio.h>
|
|
374 |
\& -: 2:
|
|
375 |
\& -: 3:int main (void)
|
|
376 |
\& function main called 1 returned 1 blocks executed 75%
|
|
377 |
\& 1: 4:{
|
|
378 |
\& 1: 5: int i, total;
|
|
379 |
\& -: 6:
|
|
380 |
\& 1: 7: total = 0;
|
|
381 |
\& -: 8:
|
|
382 |
\& 11: 9: for (i = 0; i < 10; i++)
|
|
383 |
\& 10: 10: total += i;
|
|
384 |
\& -: 11:
|
|
385 |
\& 1: 12: if (total != 45)
|
|
386 |
\& #####: 13: printf ("Failure\en");
|
|
387 |
\& -: 14: else
|
|
388 |
\& 1: 15: printf ("Success\en");
|
|
389 |
\& 1: 16: return 0;
|
|
390 |
\& -: 17:}
|
|
391 |
.Ve
|
|
392 |
.PP
|
|
393 |
When you use the \fB\-a\fR option, you will get individual block
|
|
394 |
counts, and the output looks like this:
|
|
395 |
.PP
|
|
396 |
.Vb 30
|
|
397 |
\& -: 0:Source:tmp.c
|
|
398 |
\& -: 0:Graph:tmp.gcno
|
|
399 |
\& -: 0:Data:tmp.gcda
|
|
400 |
\& -: 0:Runs:1
|
|
401 |
\& -: 0:Programs:1
|
|
402 |
\& -: 1:#include <stdio.h>
|
|
403 |
\& -: 2:
|
|
404 |
\& -: 3:int main (void)
|
|
405 |
\& function main called 1 returned 1 blocks executed 75%
|
|
406 |
\& 1: 4:{
|
|
407 |
\& 1: 4-block 0
|
|
408 |
\& 1: 5: int i, total;
|
|
409 |
\& -: 6:
|
|
410 |
\& 1: 7: total = 0;
|
|
411 |
\& -: 8:
|
|
412 |
\& 11: 9: for (i = 0; i < 10; i++)
|
|
413 |
\& 11: 9-block 0
|
|
414 |
\& 10: 10: total += i;
|
|
415 |
\& 10: 10-block 0
|
|
416 |
\& -: 11:
|
|
417 |
\& 1: 12: if (total != 45)
|
|
418 |
\& 1: 12-block 0
|
|
419 |
\& #####: 13: printf ("Failure\en");
|
|
420 |
\& $$$$$: 13-block 0
|
|
421 |
\& -: 14: else
|
|
422 |
\& 1: 15: printf ("Success\en");
|
|
423 |
\& 1: 15-block 0
|
|
424 |
\& 1: 16: return 0;
|
|
425 |
\& 1: 16-block 0
|
|
426 |
\& -: 17:}
|
|
427 |
.Ve
|
|
428 |
.PP
|
|
429 |
In this mode, each basic block is only shown on one line \*(-- the last
|
|
430 |
line of the block. A multi-line block will only contribute to the
|
|
431 |
execution count of that last line, and other lines will not be shown
|
|
432 |
to contain code, unless previous blocks end on those lines.
|
|
433 |
The total execution count of a line is shown and subsequent lines show
|
|
434 |
the execution counts for individual blocks that end on that line. After each
|
|
435 |
block, the branch and call counts of the block will be shown, if the
|
|
436 |
\&\fB\-b\fR option is given.
|
|
437 |
.PP
|
|
438 |
Because of the way \s-1GCC\s0 instruments calls, a call count can be shown
|
|
439 |
after a line with no individual blocks.
|
|
440 |
As you can see, line 13 contains a basic block that was not executed.
|
|
441 |
.PP
|
|
442 |
When you use the \fB\-b\fR option, your output looks like this:
|
|
443 |
.PP
|
|
444 |
.Vb 6
|
|
445 |
\& $ gcov -b tmp.c
|
|
446 |
\& 90.00% of 10 source lines executed in file tmp.c
|
|
447 |
\& 80.00% of 5 branches executed in file tmp.c
|
|
448 |
\& 80.00% of 5 branches taken at least once in file tmp.c
|
|
449 |
\& 50.00% of 2 calls executed in file tmp.c
|
|
450 |
\& Creating tmp.c.gcov.
|
|
451 |
.Ve
|
|
452 |
.PP
|
|
453 |
Here is a sample of a resulting \fItmp.c.gcov\fR file:
|
|
454 |
.PP
|
|
455 |
.Vb 29
|
|
456 |
\& -: 0:Source:tmp.c
|
|
457 |
\& -: 0:Graph:tmp.gcno
|
|
458 |
\& -: 0:Data:tmp.gcda
|
|
459 |
\& -: 0:Runs:1
|
|
460 |
\& -: 0:Programs:1
|
|
461 |
\& -: 1:#include <stdio.h>
|
|
462 |
\& -: 2:
|
|
463 |
\& -: 3:int main (void)
|
|
464 |
\& function main called 1 returned 1 blocks executed 75%
|
|
465 |
\& 1: 4:{
|
|
466 |
\& 1: 5: int i, total;
|
|
467 |
\& -: 6:
|
|
468 |
\& 1: 7: total = 0;
|
|
469 |
\& -: 8:
|
|
470 |
\& 11: 9: for (i = 0; i < 10; i++)
|
|
471 |
\& branch 0 taken 91% (fallthrough)
|
|
472 |
\& branch 1 taken 9%
|
|
473 |
\& 10: 10: total += i;
|
|
474 |
\& -: 11:
|
|
475 |
\& 1: 12: if (total != 45)
|
|
476 |
\& branch 0 taken 0% (fallthrough)
|
|
477 |
\& branch 1 taken 100%
|
|
478 |
\& #####: 13: printf ("Failure\en");
|
|
479 |
\& call 0 never executed
|
|
480 |
\& -: 14: else
|
|
481 |
\& 1: 15: printf ("Success\en");
|
|
482 |
\& call 0 called 1 returned 100%
|
|
483 |
\& 1: 16: return 0;
|
|
484 |
\& -: 17:}
|
|
485 |
.Ve
|
|
486 |
.PP
|
|
487 |
For each basic block, a line is printed after the last line of the basic
|
|
488 |
block describing the branch or call that ends the basic block. There can
|
|
489 |
be multiple branches and calls listed for a single source line if there
|
|
490 |
are multiple basic blocks that end on that line. In this case, the
|
|
491 |
branches and calls are each given a number. There is no simple way to map
|
|
492 |
these branches and calls back to source constructs. In general, though,
|
|
493 |
the lowest numbered branch or call will correspond to the leftmost construct
|
|
494 |
on the source line.
|
|
495 |
.PP
|
|
496 |
For a branch, if it was executed at least once, then a percentage
|
|
497 |
indicating the number of times the branch was taken divided by the
|
|
498 |
number of times the branch was executed will be printed. Otherwise, the
|
|
499 |
message ``never executed'' is printed.
|
|
500 |
.PP
|
|
501 |
For a call, if it was executed at least once, then a percentage
|
|
502 |
indicating the number of times the call returned divided by the number
|
|
503 |
of times the call was executed will be printed. This will usually be
|
|
504 |
100%, but may be less for functions call \f(CW\*(C`exit\*(C'\fR or \f(CW\*(C`longjmp\*(C'\fR,
|
|
505 |
and thus may not return every time they are called.
|
|
506 |
.PP
|
|
507 |
The execution counts are cumulative. If the example program were
|
|
508 |
executed again without removing the \fI.gcda\fR file, the count for the
|
|
509 |
number of times each line in the source was executed would be added to
|
|
510 |
the results of the previous run(s). This is potentially useful in
|
|
511 |
several ways. For example, it could be used to accumulate data over a
|
|
512 |
number of program runs as part of a test verification suite, or to
|
|
513 |
provide more accurate long-term information over a large number of
|
|
514 |
program runs.
|
|
515 |
.PP
|
|
516 |
The data in the \fI.gcda\fR files is saved immediately before the program
|
|
517 |
exits. For each source file compiled with \fB\-fprofile\-arcs\fR, the
|
|
518 |
profiling code first attempts to read in an existing \fI.gcda\fR file; if
|
|
519 |
the file doesn't match the executable (differing number of basic block
|
|
520 |
counts) it will ignore the contents of the file. It then adds in the
|
|
521 |
new execution counts and finally writes the data to the file.
|
|
522 |
.Sh "Using \fBgcov\fP with \s-1GCC\s0 Optimization"
|
|
523 |
.IX Subsection "Using gcov with GCC Optimization"
|
|
524 |
If you plan to use \fBgcov\fR to help optimize your code, you must
|
|
525 |
first compile your program with two special \s-1GCC\s0 options:
|
|
526 |
\&\fB\-fprofile\-arcs \-ftest\-coverage\fR. Aside from that, you can use any
|
|
527 |
other \s-1GCC\s0 options; but if you want to prove that every single line
|
|
528 |
in your program was executed, you should not compile with optimization
|
|
529 |
at the same time. On some machines the optimizer can eliminate some
|
|
530 |
simple code lines by combining them with other lines. For example, code
|
|
531 |
like this:
|
|
532 |
.PP
|
|
533 |
.Vb 4
|
|
534 |
\& if (a != b)
|
|
535 |
\& c = 1;
|
|
536 |
\& else
|
|
537 |
\& c = 0;
|
|
538 |
.Ve
|
|
539 |
.PP
|
|
540 |
can be compiled into one instruction on some machines. In this case,
|
|
541 |
there is no way for \fBgcov\fR to calculate separate execution counts
|
|
542 |
for each line because there isn't separate code for each line. Hence
|
|
543 |
the \fBgcov\fR output looks like this if you compiled the program with
|
|
544 |
optimization:
|
|
545 |
.PP
|
|
546 |
.Vb 4
|
|
547 |
\& 100: 12:if (a != b)
|
|
548 |
\& 100: 13: c = 1;
|
|
549 |
\& 100: 14:else
|
|
550 |
\& 100: 15: c = 0;
|
|
551 |
.Ve
|
|
552 |
.PP
|
|
553 |
The output shows that this block of code, combined by optimization,
|
|
554 |
executed 100 times. In one sense this result is correct, because there
|
|
555 |
was only one instruction representing all four of these lines. However,
|
|
556 |
the output does not indicate how many times the result was 0 and how
|
|
557 |
many times the result was 1.
|
|
558 |
.PP
|
|
559 |
Inlineable functions can create unexpected line counts. Line counts are
|
|
560 |
shown for the source code of the inlineable function, but what is shown
|
|
561 |
depends on where the function is inlined, or if it is not inlined at all.
|
|
562 |
.PP
|
|
563 |
If the function is not inlined, the compiler must emit an out of line
|
|
564 |
copy of the function, in any object file that needs it. If
|
|
565 |
\&\fIfileA.o\fR and \fIfileB.o\fR both contain out of line bodies of a
|
|
566 |
particular inlineable function, they will also both contain coverage
|
|
567 |
counts for that function. When \fIfileA.o\fR and \fIfileB.o\fR are
|
|
568 |
linked together, the linker will, on many systems, select one of those
|
|
569 |
out of line bodies for all calls to that function, and remove or ignore
|
|
570 |
the other. Unfortunately, it will not remove the coverage counters for
|
|
571 |
the unused function body. Hence when instrumented, all but one use of
|
|
572 |
that function will show zero counts.
|
|
573 |
.PP
|
|
574 |
If the function is inlined in several places, the block structure in
|
|
575 |
each location might not be the same. For instance, a condition might
|
|
576 |
now be calculable at compile time in some instances. Because the
|
|
577 |
coverage of all the uses of the inline function will be shown for the
|
|
578 |
same source lines, the line counts themselves might seem inconsistent.
|
|
579 |
.SH "SEE ALSO"
|
|
580 |
.IX Header "SEE ALSO"
|
|
581 |
\&\fIgpl\fR\|(7), \fIgfdl\fR\|(7), \fIfsf\-funding\fR\|(7), \fIgcc\fR\|(1) and the Info entry for \fIgcc\fR.
|
|
582 |
.SH "COPYRIGHT"
|
|
583 |
.IX Header "COPYRIGHT"
|
|
584 |
Copyright (c) 1996, 1997, 1999, 2000, 2001, 2002, 2003
|
|
585 |
Free Software Foundation, Inc.
|
|
586 |
.PP
|
|
587 |
Permission is granted to copy, distribute and/or modify this document
|
|
588 |
under the terms of the \s-1GNU\s0 Free Documentation License, Version 1.2 or
|
|
589 |
any later version published by the Free Software Foundation; with the
|
|
590 |
Invariant Sections being ``\s-1GNU\s0 General Public License'' and ``Funding
|
|
591 |
Free Software'', the Front-Cover texts being (a) (see below), and with
|
|
592 |
the Back-Cover Texts being (b) (see below). A copy of the license is
|
|
593 |
included in the \fIgfdl\fR\|(7) man page.
|
|
594 |
.PP
|
|
595 |
(a) The \s-1FSF\s0's Front-Cover Text is:
|
|
596 |
.PP
|
|
597 |
.Vb 1
|
|
598 |
\& A GNU Manual
|
|
599 |
.Ve
|
|
600 |
.PP
|
|
601 |
(b) The \s-1FSF\s0's Back-Cover Text is:
|
|
602 |
.PP
|
|
603 |
.Vb 3
|
|
604 |
\& You have freedom to copy and modify this GNU Manual, like GNU
|
|
605 |
\& software. Copies published by the Free Software Foundation raise
|
|
606 |
\& funds for GNU development.
|
|
607 |
.Ve
|