2011-03-18 06:21:38 +03:00
|
|
|
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
|
2009-02-14 23:20:19 +03:00
|
|
|
"http://www.w3.org/TR/html4/strict.dtd">
|
|
|
|
|
<!-- Material used from: HTML 4.01 specs: http://www.w3.org/TR/html401/ -->
|
|
|
|
|
<html>
|
|
|
|
|
<head>
|
|
|
|
|
<META http-equiv="Content-Type" content="text/html; charset=ISO-8859-1" />
|
|
|
|
|
<title>Hacking on clang</title>
|
|
|
|
|
<link type="text/css" rel="stylesheet" href="menu.css" />
|
|
|
|
|
<link type="text/css" rel="stylesheet" href="content.css" />
|
|
|
|
|
</head>
|
|
|
|
|
<body>
|
|
|
|
|
<!--#include virtual="menu.html.incl"-->
|
|
|
|
|
<div id="content">
|
|
|
|
|
<!--*********************************************************************-->
|
|
|
|
|
<h1>Hacking on Clang</h1>
|
|
|
|
|
<!--*********************************************************************-->
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2009-02-14 23:20:19 +03:00
|
|
|
<p>This document provides some hints for how to get started hacking
|
|
|
|
|
on Clang for developers who are new to the Clang and/or LLVM
|
|
|
|
|
codebases.</p>
|
|
|
|
|
<ul>
|
2010-01-22 05:04:46 +03:00
|
|
|
<li><a href="#style">Coding Standards</a></li>
|
2009-02-14 23:20:19 +03:00
|
|
|
<li><a href="#docs">Developer Documentation</a></li>
|
|
|
|
|
<li><a href="#debugging">Debugging</a></li>
|
|
|
|
|
<li><a href="#testing">Testing</a></li>
|
2009-08-03 23:42:28 +04:00
|
|
|
<ul>
|
2011-03-18 06:21:38 +03:00
|
|
|
<li><a href="#testingNonWindows">Testing on Unix-like Systems</a></li>
|
|
|
|
|
<li><a href="#testingWindows">Testing using Visual Studio on Windows</a></li>
|
|
|
|
|
<li><a href="#testingCommands">Testing on the Command Line</a></li>
|
|
|
|
|
</ul>
|
2009-08-03 23:42:28 +04:00
|
|
|
<li><a href="#patches">Creating Patch Files</a></li>
|
2009-02-14 23:20:19 +03:00
|
|
|
<li><a href="#irgen">LLVM IR Generation</a></li>
|
|
|
|
|
</ul>
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2010-01-22 05:04:46 +03:00
|
|
|
<!--=====================================================================-->
|
|
|
|
|
<h2 id="docs">Coding Standards</h2>
|
|
|
|
|
<!--=====================================================================-->
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2010-01-22 05:04:46 +03:00
|
|
|
<p>Clang follows the
|
|
|
|
|
LLVM <a href="http://llvm.org/docs/CodingStandards.html">Coding
|
|
|
|
|
Standards</a>. When submitting patches, please take care to follow these standards
|
|
|
|
|
and to match the style of the code to that present in Clang (for example, in
|
|
|
|
|
terms of indentation, bracing, and statement spacing).</p>
|
|
|
|
|
|
|
|
|
|
<p>Clang has a few additional coding standards:</p>
|
|
|
|
|
<ul>
|
|
|
|
|
<li><i>cstdio is forbidden</i>: library code should not output diagnostics
|
|
|
|
|
or other information using <tt>cstdio</tt>; debugging routines should
|
|
|
|
|
use <tt>llvm::errs()</tt>. Other uses of <tt>cstdio</tt> impose behavior
|
|
|
|
|
upon clients and block integrating Clang as a library. Libraries should
|
|
|
|
|
support <tt>raw_ostream</tt> based interfaces for textual
|
|
|
|
|
output. See <a href="http://llvm.org/docs/CodingStandards.html#ll_raw_ostream">Coding
|
|
|
|
|
Standards</a>.</li>
|
|
|
|
|
</ul>
|
|
|
|
|
|
2009-02-14 23:20:19 +03:00
|
|
|
<!--=====================================================================-->
|
|
|
|
|
<h2 id="docs">Developer Documentation</h2>
|
|
|
|
|
<!--=====================================================================-->
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2009-02-14 23:20:19 +03:00
|
|
|
<p>Both Clang and LLVM use doxygen to provide API documentation. Their
|
|
|
|
|
respective web pages (generated nightly) are here:</p>
|
|
|
|
|
<ul>
|
|
|
|
|
<li><a href="http://clang.llvm.org/doxygen">Clang</a></li>
|
|
|
|
|
<li><a href="http://llvm.org/doxygen">LLVM</a></li>
|
|
|
|
|
</ul>
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2009-02-14 23:20:19 +03:00
|
|
|
<p>For work on the LLVM IR generation, the LLVM assembly language
|
|
|
|
|
<a href="http://llvm.org/docs/LangRef.html">reference manual</a> is
|
|
|
|
|
also useful.</p>
|
|
|
|
|
|
|
|
|
|
<!--=====================================================================-->
|
|
|
|
|
<h2 id="debugging">Debugging</h2>
|
|
|
|
|
<!--=====================================================================-->
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2009-02-14 23:20:19 +03:00
|
|
|
<p>Inspecting data structures in a debugger:</p>
|
|
|
|
|
<ul>
|
|
|
|
|
<li>Many LLVM and Clang data structures provide
|
|
|
|
|
a <tt>dump()</tt> method which will print a description of the
|
|
|
|
|
data structure to <tt>stderr</tt>.</li>
|
|
|
|
|
<li>The <a href="docs/InternalsManual.html#QualType"><tt>QualType</tt></a>
|
|
|
|
|
structure is used pervasively. This is a simple value class for
|
|
|
|
|
wrapping types with qualifiers; you can use
|
|
|
|
|
the <tt>isConstQualified()</tt>, for example, to get one of the
|
|
|
|
|
qualifiers, and the <tt>getTypePtr()</tt> method to get the
|
|
|
|
|
wrapped <tt>Type*</tt> which you can then dump.</li>
|
|
|
|
|
</ul>
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2009-02-14 23:20:19 +03:00
|
|
|
<!--=====================================================================-->
|
|
|
|
|
<h2 id="testing">Testing</h2>
|
|
|
|
|
<!--=====================================================================-->
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2009-08-03 23:42:28 +04:00
|
|
|
<p><i>[Note: The test running mechanism is currently under revision, so the
|
|
|
|
|
following might change shortly.]</i></p>
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2009-08-03 23:42:28 +04:00
|
|
|
<!--=====================================================================-->
|
|
|
|
|
<h3 id="testingNonWindows">Testing on Unix-like Systems</h3>
|
|
|
|
|
<!--=====================================================================-->
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2009-02-14 23:20:19 +03:00
|
|
|
<p>Clang includes a basic regression suite in the tree which can be
|
|
|
|
|
run with <tt>make test</tt> from the top-level clang directory, or
|
2009-08-03 23:42:28 +04:00
|
|
|
just <tt>make</tt> in the <em>test</em> sub-directory.
|
|
|
|
|
<tt>make VERBOSE=1</tt> can be used to show more detail
|
2009-02-14 23:20:19 +03:00
|
|
|
about what is being run.</p>
|
|
|
|
|
|
2010-06-10 21:01:45 +04:00
|
|
|
<p>If you built LLVM and Clang using CMake, the test suite can be run
|
|
|
|
|
with <tt>make clang-test</tt> from the top-level LLVM directory.</p>
|
|
|
|
|
|
2009-08-03 23:42:28 +04:00
|
|
|
<p>The tests primarily consist of a test runner script running the compiler
|
|
|
|
|
under test on individual test files grouped in the directories under the
|
|
|
|
|
test directory. The individual test files include comments at the
|
|
|
|
|
beginning indicating the Clang compile options to use, to be read
|
|
|
|
|
by the test runner. Embedded comments also can do things like telling
|
|
|
|
|
the test runner that an error is expected at the current line.
|
|
|
|
|
Any output files produced by the test will be placed under
|
|
|
|
|
a created Output directory.</p>
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2009-08-03 23:42:28 +04:00
|
|
|
<p>During the run of <tt>make test</tt>, the terminal output will
|
|
|
|
|
display a line similar to the following:</p>
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2009-08-03 23:42:28 +04:00
|
|
|
<ul><tt>--- Running clang tests for i686-pc-linux-gnu ---</tt></ul>
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2009-08-03 23:42:28 +04:00
|
|
|
<p>followed by a line continually overwritten with the current test
|
|
|
|
|
file being compiled, and an overall completion percentage.</p>
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2009-08-03 23:42:28 +04:00
|
|
|
<p>After the <tt>make test</tt> run completes, the absence of any
|
|
|
|
|
<tt>Failing Tests (count):</tt> message indicates that no tests
|
|
|
|
|
failed unexpectedly. If any tests did fail, the
|
|
|
|
|
<tt>Failing Tests (count):</tt> message will be followed by a list
|
|
|
|
|
of the test source file paths that failed. For example:</p>
|
|
|
|
|
|
|
|
|
|
<tt><pre>
|
|
|
|
|
Failing Tests (3):
|
|
|
|
|
/home/john/llvm/tools/clang/test/SemaCXX/member-name-lookup.cpp
|
|
|
|
|
/home/john/llvm/tools/clang/test/SemaCXX/namespace-alias.cpp
|
|
|
|
|
/home/john/llvm/tools/clang/test/SemaCXX/using-directive.cpp
|
|
|
|
|
</pre></tt>
|
|
|
|
|
|
|
|
|
|
<p>If you used the <tt>make VERBOSE=1</tt> option, the terminal
|
|
|
|
|
output will reflect the error messages from the compiler and
|
|
|
|
|
test runner.</p>
|
|
|
|
|
|
2009-02-14 23:20:19 +03:00
|
|
|
<p>The regression suite can also be run with Valgrind by running
|
|
|
|
|
<tt>make test VG=1</tt> in the top-level clang directory.</p>
|
|
|
|
|
|
|
|
|
|
<p>For more intensive changes, running
|
|
|
|
|
the <a href="http://llvm.org/docs/TestingGuide.html#testsuiterun">LLVM
|
|
|
|
|
Test Suite</a> with clang is recommended. Currently the best way to
|
2009-08-06 20:47:53 +04:00
|
|
|
override LLVMGCC, as in: <tt>make LLVMGCC="clang -std=gnu89"
|
|
|
|
|
TEST=nightly report</tt> (make sure <tt>clang</tt> is in your PATH or use the
|
2009-02-14 23:20:19 +03:00
|
|
|
full path).</p>
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2009-08-03 23:42:28 +04:00
|
|
|
<!--=====================================================================-->
|
|
|
|
|
<h3 id="testingWindows">Testing using Visual Studio on Windows</h3>
|
|
|
|
|
<!--=====================================================================-->
|
|
|
|
|
|
2009-11-06 03:06:29 +03:00
|
|
|
<p>The Clang test suite can be run from either Visual Studio or
|
|
|
|
|
the command line.</p>
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2009-11-06 03:06:29 +03:00
|
|
|
<p>Note that the test runner is based on
|
2009-08-03 23:42:28 +04:00
|
|
|
Python, which must be installed. Find Python at:
|
2011-03-18 06:21:38 +03:00
|
|
|
<a href="http://www.python.org/download/">http://www.python.org/download/</a>.
|
2009-08-03 23:42:28 +04:00
|
|
|
Download the latest stable version (2.6.2 at the time of this writing).</p>
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2009-08-20 10:17:11 +04:00
|
|
|
<p>The GnuWin32 tools are also necessary for running the tests.
|
2011-03-18 06:21:38 +03:00
|
|
|
Get them from <a href="http://getgnuwin32.sourceforge.net/">
|
2011-03-18 06:21:44 +03:00
|
|
|
http://getgnuwin32.sourceforge.net/</a>.
|
|
|
|
|
If the environment variable <tt>%PATH%</tt> does not have GnuWin32,
|
|
|
|
|
or if other grep(s) supercedes GnuWin32 on <tt>%PATH%,</tt>
|
|
|
|
|
you should specify <tt>LLVM_LIT_TOOLS_DIR</tt>
|
|
|
|
|
to CMake explicitly.</p>
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2009-11-06 03:06:29 +03:00
|
|
|
<p>The cmake build tool is set up to create Visual Studio project files
|
|
|
|
|
for running the tests, "clang-test" being the root. Therefore, to
|
|
|
|
|
run the test from Visual Studio, right-click the clang-test project
|
|
|
|
|
and select "Build".</p>
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2011-03-18 06:21:44 +03:00
|
|
|
<p>
|
|
|
|
|
Please see also
|
|
|
|
|
<a href="http://llvm.org/docs/GettingStartedVS.html">Getting Started
|
|
|
|
|
with the LLVM System using Microsoft Visual Studio</a> and
|
|
|
|
|
<a href="http://llvm.org/docs/CMake.html">Building LLVM with CMake</a>.
|
|
|
|
|
</p>
|
|
|
|
|
|
2010-09-03 21:01:13 +04:00
|
|
|
<!--=====================================================================-->
|
|
|
|
|
<h3 id="testingCommands">Testing on the Command Line</h3>
|
|
|
|
|
<!--=====================================================================-->
|
|
|
|
|
|
2009-11-06 03:06:29 +03:00
|
|
|
<p>To run all the tests from the command line, execute a command like
|
|
|
|
|
the following:</p>
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2009-11-06 03:06:29 +03:00
|
|
|
<tt>
|
|
|
|
|
python (path to llvm)/llvm/utils/lit/lit.py -sv --no-progress-bar
|
|
|
|
|
(path to llvm)/llvm/tools/clang/test
|
|
|
|
|
</tt>
|
|
|
|
|
|
2011-01-24 21:04:58 +03:00
|
|
|
<p>For CMake builds e.g. on Windows with Visual Studio, you will need
|
|
|
|
|
to specify your build configuration (Debug, Release, etc.) via
|
|
|
|
|
<tt>--param=build_config=(build config)</tt>.</p>
|
|
|
|
|
|
2009-11-06 03:06:29 +03:00
|
|
|
<p>To run a single test:</p>
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2009-11-06 03:06:29 +03:00
|
|
|
<tt>
|
|
|
|
|
python (path to llvm)/llvm/utils/lit/lit.py -sv --no-progress-bar
|
|
|
|
|
(path to llvm)/llvm/tools/clang/test/(dir)/(test)
|
|
|
|
|
</tt>
|
|
|
|
|
|
|
|
|
|
<p>For example:</p>
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2009-11-06 03:06:29 +03:00
|
|
|
<tt>
|
|
|
|
|
python C:/Tools/llvm/utils/lit/lit.py -sv --no-progress-bar
|
|
|
|
|
C:/Tools/llvm/tools/clang/test/Sema/wchar.c
|
|
|
|
|
</tt>
|
|
|
|
|
|
|
|
|
|
<p>The -sv option above tells the runner to show the test output if
|
|
|
|
|
any tests failed, to help you determine the cause of failure.</p>
|
|
|
|
|
|
2010-09-12 01:16:11 +04:00
|
|
|
<p>Your output might look something like this:</p>
|
|
|
|
|
|
|
|
|
|
<tt><pre>lit.py: lit.cfg:152: note: using clang: 'C:/Tools/llvm/bin/Release\\clang.EXE'
|
|
|
|
|
-- Testing: Testing: 2534 tests, 4 threads --
|
|
|
|
|
Testing: 0 .. 10.. 20.. 30.. 40.. 50.. 60.. 70.. 80.. 90..
|
|
|
|
|
Testing Time: 81.52s
|
|
|
|
|
Expected Passes : 2503
|
|
|
|
|
Expected Failures : 28
|
|
|
|
|
Unsupported Tests : 3
|
2011-03-18 06:21:38 +03:00
|
|
|
</pre></tt>
|
2009-11-06 03:06:29 +03:00
|
|
|
|
2010-09-12 01:16:11 +04:00
|
|
|
<p>The statistic, "Unexpected Failures" (not shown if all tests pass), is the important one.</p>
|
2009-08-03 23:42:28 +04:00
|
|
|
|
|
|
|
|
<!--=====================================================================-->
|
|
|
|
|
<h2 id="patches">Creating Patch Files</h2>
|
|
|
|
|
<!--=====================================================================-->
|
|
|
|
|
|
|
|
|
|
<p>To return changes to the Clang team, unless you have checkin
|
2011-04-15 09:22:18 +04:00
|
|
|
privileges, the preferred way is to send patch files to the
|
2009-08-03 23:42:28 +04:00
|
|
|
cfe-commits mailing list, with an explanation of what the patch is for.
|
|
|
|
|
Or, if you have questions, or want to have a wider discussion of what
|
|
|
|
|
you are doing, such as if you are new to Clang development, you can use
|
|
|
|
|
the cfe-dev mailing list also.
|
|
|
|
|
</p>
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2009-08-03 23:42:28 +04:00
|
|
|
<p>To create these patch files, change directory
|
|
|
|
|
to the llvm/tools/clang root and run:</p>
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2009-08-03 23:42:28 +04:00
|
|
|
<ul><tt>svn diff (relative path) >(patch file name)</tt></ul>
|
|
|
|
|
|
|
|
|
|
<p>For example, for getting the diffs of all of clang:</p>
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2009-08-03 23:42:28 +04:00
|
|
|
<ul><tt>svn diff . >~/mypatchfile.patch</tt></ul>
|
|
|
|
|
|
|
|
|
|
<p>For example, for getting the diffs of a single file:</p>
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2009-08-03 23:42:28 +04:00
|
|
|
<ul><tt>svn diff lib/Parse/ParseDeclCXX.cpp >~/ParseDeclCXX.patch</tt></ul>
|
|
|
|
|
|
|
|
|
|
<p>Note that the paths embedded in the patch depend on where you run it,
|
|
|
|
|
so changing directory to the llvm/tools/clang directory is recommended.</p>
|
2009-02-14 23:20:19 +03:00
|
|
|
|
|
|
|
|
<!--=====================================================================-->
|
|
|
|
|
<h2 id="irgen">LLVM IR Generation</h2>
|
|
|
|
|
<!--=====================================================================-->
|
|
|
|
|
|
|
|
|
|
<p>The LLVM IR generation part of clang handles conversion of the
|
|
|
|
|
AST nodes output by the Sema module to the LLVM Intermediate
|
|
|
|
|
Representation (IR). Historically, this was referred to as
|
|
|
|
|
"codegen", and the Clang code for this lives
|
|
|
|
|
in <tt>lib/CodeGen</tt>.</p>
|
2011-03-18 06:21:38 +03:00
|
|
|
|
2009-02-14 23:20:19 +03:00
|
|
|
<p>The output is most easily inspected using the <tt>-emit-llvm</tt>
|
|
|
|
|
option to clang (possibly in conjunction with <tt>-o -</tt>). You
|
|
|
|
|
can also use <tt>-emit-llvm-bc</tt> to write an LLVM bitcode file
|
|
|
|
|
which can be processed by the suite of LLVM tools
|
|
|
|
|
like <tt>llvm-dis</tt>, <tt>llvm-nm</tt>, etc. See the LLVM
|
|
|
|
|
<a href="http://llvm.org/docs/CommandGuide/">Command Guide</a>
|
|
|
|
|
for more information.</p>
|
|
|
|
|
|
|
|
|
|
</div>
|
|
|
|
|
</body>
|
|
|
|
|
</html>
|
