You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
116 lines
5.8 KiB
HTML
116 lines
5.8 KiB
HTML
<html lang="en">
|
|
<head>
|
|
<title>gcov Testing - GNU Compiler Collection (GCC) Internals</title>
|
|
<meta http-equiv="Content-Type" content="text/html">
|
|
<meta name="description" content="GNU Compiler Collection (GCC) Internals">
|
|
<meta name="generator" content="makeinfo 4.13">
|
|
<link title="Top" rel="start" href="index.html#Top">
|
|
<link rel="up" href="Testsuites.html#Testsuites" title="Testsuites">
|
|
<link rel="prev" href="LTO-Testing.html#LTO-Testing" title="LTO Testing">
|
|
<link rel="next" href="profopt-Testing.html#profopt-Testing" title="profopt Testing">
|
|
<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage">
|
|
<!--
|
|
Copyright (C) 1988-2015 Free Software Foundation, Inc.
|
|
|
|
Permission is granted to copy, distribute and/or modify this document
|
|
under the terms of the GNU Free Documentation License, Version 1.3 or
|
|
any later version published by the Free Software Foundation; with the
|
|
Invariant Sections being ``Funding Free Software'', the Front-Cover
|
|
Texts being (a) (see below), and with the Back-Cover Texts being (b)
|
|
(see below). A copy of the license is included in the section entitled
|
|
``GNU Free Documentation License''.
|
|
|
|
(a) The FSF's Front-Cover Text is:
|
|
|
|
A GNU Manual
|
|
|
|
(b) The FSF's Back-Cover Text is:
|
|
|
|
You have freedom to copy and modify this GNU Manual, like GNU
|
|
software. Copies published by the Free Software Foundation raise
|
|
funds for GNU development.-->
|
|
<meta http-equiv="Content-Style-Type" content="text/css">
|
|
<style type="text/css"><!--
|
|
pre.display { font-family:inherit }
|
|
pre.format { font-family:inherit }
|
|
pre.smalldisplay { font-family:inherit; font-size:smaller }
|
|
pre.smallformat { font-family:inherit; font-size:smaller }
|
|
pre.smallexample { font-size:smaller }
|
|
pre.smalllisp { font-size:smaller }
|
|
span.sc { font-variant:small-caps }
|
|
span.roman { font-family:serif; font-weight:normal; }
|
|
span.sansserif { font-family:sans-serif; font-weight:normal; }
|
|
--></style>
|
|
</head>
|
|
<body>
|
|
<div class="node">
|
|
<a name="gcov-Testing"></a>
|
|
<p>
|
|
Next: <a rel="next" accesskey="n" href="profopt-Testing.html#profopt-Testing">profopt Testing</a>,
|
|
Previous: <a rel="previous" accesskey="p" href="LTO-Testing.html#LTO-Testing">LTO Testing</a>,
|
|
Up: <a rel="up" accesskey="u" href="Testsuites.html#Testsuites">Testsuites</a>
|
|
<hr>
|
|
</div>
|
|
|
|
<h3 class="section">7.7 Support for testing <samp><span class="command">gcov</span></samp></h3>
|
|
|
|
<p>Language-independent support for testing <samp><span class="command">gcov</span></samp>, and for checking
|
|
that branch profiling produces expected values, is provided by the
|
|
expect file <samp><span class="file">lib/gcov.exp</span></samp>. <samp><span class="command">gcov</span></samp> tests also rely on procedures
|
|
in <samp><span class="file">lib/gcc-dg.exp</span></samp> to compile and run the test program. A typical
|
|
<samp><span class="command">gcov</span></samp> test contains the following DejaGnu commands within comments:
|
|
|
|
<pre class="smallexample"> { dg-options "-fprofile-arcs -ftest-coverage" }
|
|
{ dg-do run { target native } }
|
|
{ dg-final { run-gcov sourcefile } }
|
|
</pre>
|
|
<p>Checks of <samp><span class="command">gcov</span></samp> output can include line counts, branch percentages,
|
|
and call return percentages. All of these checks are requested via
|
|
commands that appear in comments in the test's source file.
|
|
Commands to check line counts are processed by default.
|
|
Commands to check branch percentages and call return percentages are
|
|
processed if the <samp><span class="command">run-gcov</span></samp> command has arguments <code>branches</code>
|
|
or <code>calls</code>, respectively. For example, the following specifies
|
|
checking both, as well as passing <samp><span class="option">-b</span></samp> to <samp><span class="command">gcov</span></samp>:
|
|
|
|
<pre class="smallexample"> { dg-final { run-gcov branches calls { -b sourcefile } } }
|
|
</pre>
|
|
<p>A line count command appears within a comment on the source line
|
|
that is expected to get the specified count and has the form
|
|
<code>count(</code><var>cnt</var><code>)</code>. A test should only check line counts for
|
|
lines that will get the same count for any architecture.
|
|
|
|
<p>Commands to check branch percentages (<code>branch</code>) and call
|
|
return percentages (<code>returns</code>) are very similar to each other.
|
|
A beginning command appears on or before the first of a range of
|
|
lines that will report the percentage, and the ending command
|
|
follows that range of lines. The beginning command can include a
|
|
list of percentages, all of which are expected to be found within
|
|
the range. A range is terminated by the next command of the same
|
|
kind. A command <code>branch(end)</code> or <code>returns(end)</code> marks
|
|
the end of a range without starting a new one. For example:
|
|
|
|
<pre class="smallexample"> if (i > 10 && j > i && j < 20) /* <span class="roman">branch(27 50 75)</span> */
|
|
/* <span class="roman">branch(end)</span> */
|
|
foo (i, j);
|
|
</pre>
|
|
<p>For a call return percentage, the value specified is the
|
|
percentage of calls reported to return. For a branch percentage,
|
|
the value is either the expected percentage or 100 minus that
|
|
value, since the direction of a branch can differ depending on the
|
|
target or the optimization level.
|
|
|
|
<p>Not all branches and calls need to be checked. A test should not
|
|
check for branches that might be optimized away or replaced with
|
|
predicated instructions. Don't check for calls inserted by the
|
|
compiler or ones that might be inlined or optimized away.
|
|
|
|
<p>A single test can check for combinations of line counts, branch
|
|
percentages, and call return percentages. The command to check a
|
|
line count must appear on the line that will report that count, but
|
|
commands to check branch percentages and call return percentages can
|
|
bracket the lines that report them.
|
|
|
|
</body></html>
|
|
|