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Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]6 <title>Clang - Getting Started</title>
Benjamin Kramereaa262b2012-01-15 15:26:07 +0000[diff] [blame]7 <link type="text/css" rel="stylesheet" href="menu.css">
8 <link type="text/css" rel="stylesheet" href="content.css">
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]9</head>
10<body>
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12<!--#include virtual="menu.html.incl"-->
13
14<div id="content">
15
16<h1>Getting Started: Building and Running Clang</h1>
17
Ted Kremenekb3e8f652009-03-27 16:32:57 +0000[diff] [blame]18<p>This page gives you the shortest path to checking out Clang and demos a few
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]19options. This should get you up and running with the minimum of muss and fuss.
20If you like what you see, please consider <a href="get_involved.html">getting
Chris Lattnerb8ca9542009-11-09 03:18:18 +0000[diff] [blame]21involved</a> with the Clang community. If you run into problems, please file
Douglas Gregora8810102010-10-07 20:20:57 +0000[diff] [blame]22bugs in <a href="http://llvm.org/bugs/">LLVM Bugzilla</a>.</p>
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]23
Daniel Dunbar6b835382010-11-02 22:34:04 +0000[diff] [blame]24<h2 id="download">Release Clang Versions</h2>
25
Sylvestre Ledru7db5ab42014-04-27 15:17:15 +0000[diff] [blame]26<p>Clang is released as part of regular LLVM releases. You can download the release versions from <a href="http://llvm.org/releases/">http://llvm.org/releases/</a>.</p>
27<p>Clang is also provided in all major BSD or GNU/Linux distributions as part of their respective packaging systems. From Xcode 4.2, Clang is the default compiler for Mac OS X.</p>
Daniel Dunbar6b835382010-11-02 22:34:04 +0000[diff] [blame]28
Ted Kremenekb3e8f652009-03-27 16:32:57 +0000[diff] [blame]29<h2 id="build">Building Clang and Working with the Code</h2>
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]30
Eli Friedman05194922009-08-03 19:42:28 +0000[diff] [blame]31<h3 id="buildNix">On Unix-like Systems</h3>
32
Ted Kremenekb3e8f652009-03-27 16:32:57 +0000[diff] [blame]33<p>If you would like to check out and build Clang, the current procedure is as
34follows:</p>
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]35
36<ol>
Anton Korobeynikov3ebc08b2009-08-06 13:00:08 +0000[diff] [blame]37 <li>Get the required tools.
38 <ul>
39 <li>See
40 <a href="http://llvm.org/docs/GettingStarted.html#requirements">
41 Getting Started with the LLVM System - Requirements</a>.</li>
42 <li>Note also that Python is needed for running the test suite.
43 Get it at: <a href="http://www.python.org/download">
44 http://www.python.org/download</a></li>
Alexey Samsonovec0bff92015-04-21 18:38:31 +0000[diff] [blame]45 <li>Standard build process uses CMake. Get it at:
46 <a href="http://www.cmake.org/download">
47 http://www.cmake.org/download</a></li>
Anton Korobeynikov3ebc08b2009-08-06 13:00:08 +0000[diff] [blame]48 </ul>
49
Adrian McCarthy02d0a632016-04-20 16:43:34 +0000[diff] [blame]50 <li>Check out LLVM:
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]51 <ul>
Chris Lattnerf6bad862009-08-20 06:17:11 +0000[diff] [blame]52 <li>Change directory to where you want the llvm directory placed.</li>
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]53 <li><tt>svn co http://llvm.org/svn/llvm-project/llvm/trunk llvm</tt></li>
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]54 </ul>
Benjamin Kramereaa262b2012-01-15 15:26:07 +0000[diff] [blame]55 </li>
Adrian McCarthy02d0a632016-04-20 16:43:34 +0000[diff] [blame]56 <li>Check out Clang:
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]57 <ul>
Chandler Carruth18d67452012-08-14 00:41:30 +0000[diff] [blame]58 <li><tt>cd llvm/tools</tt></li>
Chris Lattnerf6bad862009-08-20 06:17:11 +0000[diff] [blame]59 <li><tt>svn co http://llvm.org/svn/llvm-project/cfe/trunk clang</tt></li>
Chandler Carruth18d67452012-08-14 00:41:30 +0000[diff] [blame]60 <li><tt>cd ../..</tt></li>
Chris Lattnerf6bad862009-08-20 06:17:11 +0000[diff] [blame]61 </ul>
Benjamin Kramereaa262b2012-01-15 15:26:07 +0000[diff] [blame]62 </li>
Adrian McCarthy02d0a632016-04-20 16:43:34 +0000[diff] [blame]63 <li>Check out extra Clang tools: (optional)
Chandler Carruth72af8c32012-08-14 07:19:09 +0000[diff] [blame]64 <ul>
65 <li><tt>cd llvm/tools/clang/tools</tt></li>
66 <li><tt>svn co http://llvm.org/svn/llvm-project/clang-tools-extra/trunk
67 extra</tt></li>
68 <li><tt>cd ../../../..</tt></li>
69 </ul>
70 </li>
Adrian McCarthy02d0a632016-04-20 16:43:34 +0000[diff] [blame]71 <li>Check out Compiler-RT (optional):
Daniel Dunbar2931cd92011-12-07 03:04:42 +0000[diff] [blame]72 <ul>
Chandler Carruth18d67452012-08-14 00:41:30 +0000[diff] [blame]73 <li><tt>cd llvm/projects</tt></li>
Daniel Dunbar2931cd92011-12-07 03:04:42 +0000[diff] [blame]74 <li><tt>svn co http://llvm.org/svn/llvm-project/compiler-rt/trunk
75 compiler-rt</tt></li>
Chandler Carruth18d67452012-08-14 00:41:30 +0000[diff] [blame]76 <li><tt>cd ../..</tt></li>
Daniel Dunbar2931cd92011-12-07 03:04:42 +0000[diff] [blame]77 </ul>
Benjamin Kramereaa262b2012-01-15 15:26:07 +0000[diff] [blame]78 </li>
Adrian McCarthy02d0a632016-04-20 16:43:34 +0000[diff] [blame]79 <li>Check out libcxx: (only required to build and run Compiler-RT tests on OS X, optional otherwise)
Yury Gribovdaace1b2015-09-15 15:05:47 +0000[diff] [blame]80 <ul>
81 <li><tt>cd llvm/projects</tt></li>
82 <li><tt>svn co http://llvm.org/svn/llvm-project/libcxx/trunk
83 libcxx</tt></li>
84 <li><tt>cd ../..</tt></li>
85 </ul>
86 </li>
Benjamin Kramereaa262b2012-01-15 15:26:07 +0000[diff] [blame]87 <li>Build LLVM and Clang:
Chris Lattnerf6bad862009-08-20 06:17:11 +0000[diff] [blame]88 <ul>
Alexey Samsonovec0bff92015-04-21 18:38:31 +0000[diff] [blame]89 <li><tt>mkdir build</tt> (in-tree build is not supported)</li>
Rafael Espindola4f8857e2010-10-29 22:05:17 +0000[diff] [blame]90 <li><tt>cd build</tt></li>
Alexey Samsonovec0bff92015-04-21 18:38:31 +0000[diff] [blame]91 <li><tt>cmake -G "Unix Makefiles" ../llvm</tt></li>
Chris Lattnerf6bad862009-08-20 06:17:11 +0000[diff] [blame]92 <li><tt>make</tt></li>
93 <li>This builds both LLVM and Clang for debug mode.</li>
Alexey Samsonovec0bff92015-04-21 18:38:31 +0000[diff] [blame]94 <li>Note: For subsequent Clang development, you can just run
95 <tt>make clang</tt>.</li>
96 <li>CMake allows you to generate project files for several IDEs: Xcode,
97 Eclipse CDT4, CodeBlocks, Qt-Creator (use the CodeBlocks generator),
98 KDevelop3. For more details see
99 <a href="http://llvm.org/docs/CMake.html">Building LLVM with CMake</a>
100 page.</li>
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]101 </ul>
Benjamin Kramereaa262b2012-01-15 15:26:07 +0000[diff] [blame]102 </li>
Chris Lattner6eeb2212010-05-06 21:57:57 +0000[diff] [blame]103
Richard Smith9deb9d92013-03-12 19:56:09 +0000[diff] [blame]104 <li>If you intend to use Clang's C++ support, you may need to tell it how
Chandler Carruthcc312312012-05-16 08:18:58 +0000[diff] [blame]105 to find your C++ standard library headers. In general, Clang will detect
106 the best version of libstdc++ headers available and use them - it will
107 look both for system installations of libstdc++ as well as installations
108 adjacent to Clang itself. If your configuration fits neither of these
Justin Bogner78a9db72015-12-10 20:52:59 +0000[diff] [blame]109 scenarios, you can use the <tt>-DGCC_INSTALL_PREFIX</tt> cmake option
Chandler Carruthcc312312012-05-16 08:18:58 +0000[diff] [blame]110 to tell Clang where the gcc containing the desired libstdc++ is installed.
Benjamin Kramereaa262b2012-01-15 15:26:07 +0000[diff] [blame]111 </li>
Reid Kleckner88cbe5a2016-04-11 17:02:34 +0000[diff] [blame]112 <li>Try it out (assuming you add llvm/build/bin to your path):
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]113 <ul>
Daniel Dunbar520d1e62009-12-11 23:04:35 +0000[diff] [blame]114 <li><tt>clang --help</tt></li>
115 <li><tt>clang file.c -fsyntax-only</tt> (check for correctness)</li>
116 <li><tt>clang file.c -S -emit-llvm -o -</tt> (print out unoptimized llvm code)</li>
117 <li><tt>clang file.c -S -emit-llvm -o - -O3</tt></li>
118 <li><tt>clang file.c -S -O3 -o -</tt> (output native machine code)</li>
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]119 </ul>
Benjamin Kramereaa262b2012-01-15 15:26:07 +0000[diff] [blame]120 </li>
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]121</ol>
122
Reid Kleckner88cbe5a2016-04-11 17:02:34 +0000[diff] [blame]123<p>If you encounter problems while building Clang, make sure that your LLVM
124checkout is at the same revision as your Clang checkout. LLVM's interfaces
125change over time, and mismatched revisions are not expected to work
126together.</p>
Adrian McCarthy02d0a632016-04-20 16:43:34 +0000[diff] [blame]127
Ted Kremenekb3e8f652009-03-27 16:32:57 +0000[diff] [blame]128<h3>Simultaneously Building Clang and LLVM:</h3>
Eric Christopher6aa87cb2008-02-08 07:10:48 +0000[diff] [blame]129
Ted Kremenekb3e8f652009-03-27 16:32:57 +0000[diff] [blame]130<p>Once you have checked out Clang into the llvm source tree it will build along
131with the rest of <tt>llvm</tt>. To build all of LLVM and Clang together all at
132once simply run <tt>make</tt> from the root LLVM directory.</p>
Adrian McCarthy02d0a632016-04-20 16:43:34 +0000[diff] [blame]133
Ted Kremenekb3e8f652009-03-27 16:32:57 +0000[diff] [blame]134<p><em>Note:</em> Observe that Clang is technically part of a separate
135Subversion repository. As mentioned above, the latest Clang sources are tied to
136the latest sources in the LLVM tree. You can update your toplevel LLVM project
137and all (possibly unrelated) projects inside it with <tt><b>make
138update</b></tt>. This will run <tt>svn update</tt> on all subdirectories related
139to subversion. </p>
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]140
Eli Friedman05194922009-08-03 19:42:28 +0000[diff] [blame]141<h3 id="buildWindows">Using Visual Studio</h3>
142
143<p>The following details setting up for and building Clang on Windows using
144Visual Studio:</p>
145
146<ol>
Benjamin Kramereaa262b2012-01-15 15:26:07 +0000[diff] [blame]147 <li>Get the required tools:
Eli Friedman05194922009-08-03 19:42:28 +0000[diff] [blame]148 <ul>
149 <li><b>Subversion</b>. Source code control program. Get it from:
Yaron Keren9f887022015-05-07 15:15:16 +0000[diff] [blame]150 <a href="http://subversion.apache.org/packages.html">
151 http://subversion.apache.org/packages.html</a></li>
NAKAMURA Takumia9f3c0f2012-11-27 23:34:08 +0000[diff] [blame]152 <li><b>CMake</b>. This is used for generating Visual Studio solution and
Eli Friedman05194922009-08-03 19:42:28 +0000[diff] [blame]153 project files. Get it from:
154 <a href="http://www.cmake.org/cmake/resources/software.html">
155 http://www.cmake.org/cmake/resources/software.html</a></li>
Yaron Keren37f99ed2015-05-07 15:12:30 +0000[diff] [blame]156 <li><b>Visual Studio 2013 or later</b></li>
Chris Lattnerf6bad862009-08-20 06:17:11 +0000[diff] [blame]157 <li><b>Python</b>. This is needed only if you will be running the tests
Eli Friedman05194922009-08-03 19:42:28 +0000[diff] [blame]158 (which is essential, if you will be developing for clang).
159 Get it from:
NAKAMURA Takumi823f3eb2011-03-27 02:04:21 +0000[diff] [blame]160 <a href="http://www.python.org/download/">
161 http://www.python.org/download/</a></li>
Chris Lattnerf6bad862009-08-20 06:17:11 +0000[diff] [blame]162 <li><b>GnuWin32 tools</b>
163 These are also necessary for running the tests.
164 (Note that the grep from MSYS or Cygwin doesn't work with the tests
165 because of embedded double-quotes in the search strings. The GNU
166 grep does work in this case.)
NAKAMURA Takumi823f3eb2011-03-27 02:04:21 +0000[diff] [blame]167 Get them from <a href="http://getgnuwin32.sourceforge.net/">
168 http://getgnuwin32.sourceforge.net/</a>.</li>
Eli Friedman05194922009-08-03 19:42:28 +0000[diff] [blame]169 </ul>
Benjamin Kramereaa262b2012-01-15 15:26:07 +0000[diff] [blame]170 </li>
Eli Friedman05194922009-08-03 19:42:28 +0000[diff] [blame]171
Adrian McCarthy02d0a632016-04-20 16:43:34 +0000[diff] [blame]172 <li>Check out LLVM:
Eli Friedman05194922009-08-03 19:42:28 +0000[diff] [blame]173 <ul>
174 <li><tt>svn co http://llvm.org/svn/llvm-project/llvm/trunk llvm</tt></li>
175 </ul>
Benjamin Kramereaa262b2012-01-15 15:26:07 +0000[diff] [blame]176 </li>
Adrian McCarthy02d0a632016-04-20 16:43:34 +0000[diff] [blame]177 <li>Check out Clang:
Eli Friedman05194922009-08-03 19:42:28 +0000[diff] [blame]178 <ul>
179 <li><tt>cd llvm\tools</tt>
180 <li><tt>svn co http://llvm.org/svn/llvm-project/cfe/trunk clang</tt></li>
181 </ul>
Adrian McCarthy02d0a632016-04-20 16:43:34 +0000[diff] [blame]182 <p><em>Note</em>: Some Clang tests are sensitive to the line endings. Ensure
183 that checking out the files does not convert LF line endings to CR+LF.
184 If you use git-svn, make sure your <tt>core.autocrlf</tt> setting is false.</p>
Benjamin Kramereaa262b2012-01-15 15:26:07 +0000[diff] [blame]185 </li>
NAKAMURA Takumia9f3c0f2012-11-27 23:34:08 +0000[diff] [blame]186 <li>Run CMake to generate the Visual Studio solution and project files:
Eli Friedman05194922009-08-03 19:42:28 +0000[diff] [blame]187 <ul>
Michael J. Spencer7ed7afc2010-12-16 22:01:14 +0000[diff] [blame]188 <li><tt>cd ..\..</tt> (back to where you started)</li>
189 <li><tt>mkdir build</tt> (for building without polluting the source dir)</li>
190 <li><tt>cd build</tt></li>
Yaron Keren37f99ed2015-05-07 15:12:30 +0000[diff] [blame]191 <li>If you are using Visual Studio 2013: <tt>cmake -G "Visual Studio 12" ..\llvm</tt></li>
John Thompson9bfba162011-04-06 18:22:12 +0000[diff] [blame]192 <li>See the <a href="http://www.llvm.org/docs/CMake.html">LLVM CMake guide</a> for
NAKAMURA Takumia9f3c0f2012-11-27 23:34:08 +0000[diff] [blame]193 more information on other configuration options for CMake.</li>
Eli Friedman05194922009-08-03 19:42:28 +0000[diff] [blame]194 <li>The above, if successful, will have created an LLVM.sln file in the
NAKAMURA Takumib44cd822011-07-25 12:40:26 +0000[diff] [blame]195 <tt>build</tt> directory.
Eli Friedman05194922009-08-03 19:42:28 +0000[diff] [blame]196 </ul>
Benjamin Kramereaa262b2012-01-15 15:26:07 +0000[diff] [blame]197 </li>
198 <li>Build Clang:
Eli Friedman05194922009-08-03 19:42:28 +0000[diff] [blame]199 <ul>
200 <li>Open LLVM.sln in Visual Studio.</li>
Daniel Dunbar520d1e62009-12-11 23:04:35 +0000[diff] [blame]201 <li>Build the "clang" project for just the compiler driver and front end, or
202 the "ALL_BUILD" project to build everything, including tools.</li>
Eli Friedman05194922009-08-03 19:42:28 +0000[diff] [blame]203 </ul>
Benjamin Kramereaa262b2012-01-15 15:26:07 +0000[diff] [blame]204 </li>
Eli Friedman05194922009-08-03 19:42:28 +0000[diff] [blame]205 <li>Try it out (assuming you added llvm/debug/bin to your path). (See the
206 running examples from above.)</li>
207 <li>See <a href="hacking.html#testingWindows">
208 Hacking on clang - Testing using Visual Studio on Windows</a> for information
209 on running regression tests on Windows.</li>
210</ol>
211
212<p>Note that once you have checked out both llvm and clang, to synchronize
213to the latest code base, use the <tt>svn update</tt> command in both the
214llvm and llvm\tools\clang directories, as they are separate repositories.</p>
215
Benjamin Kramereaa262b2012-01-15 15:26:07 +0000[diff] [blame]216<h2 id="driver">Clang Compiler Driver (Drop-in Substitute for GCC)</h2>
Ted Kremenekb3e8f652009-03-27 16:32:57 +0000[diff] [blame]217
Daniel Dunbar520d1e62009-12-11 23:04:35 +0000[diff] [blame]218<p>The <tt>clang</tt> tool is the compiler driver and front-end, which is
219designed to be a drop-in replacement for the <tt>gcc</tt> command. Here are
220some examples of how to use the high-level driver:
Ted Kremenekb3e8f652009-03-27 16:32:57 +0000[diff] [blame]221</p>
222
223<pre class="code">
224$ <b>cat t.c</b>
225#include &lt;stdio.h&gt;
226int main(int argc, char **argv) { printf("hello world\n"); }
227$ <b>clang t.c</b>
228$ <b>./a.out</b>
229hello world
230</pre>
231
Chris Lattnere5eb7262009-11-09 03:21:02 +0000[diff] [blame]232<p>The 'clang' driver is designed to work as closely to GCC as possible to
233 maximize portability. The only major difference between the two is that
234 Clang defaults to gnu99 mode while GCC defaults to gnu89 mode. If you see
Chris Lattnere6e64be2009-11-09 04:04:07 +0000[diff] [blame]235 weird link-time errors relating to inline functions, try passing -std=gnu89
Chris Lattnere5eb7262009-11-09 03:21:02 +0000[diff] [blame]236 to clang.</p>
237
Ted Kremenekb3e8f652009-03-27 16:32:57 +0000[diff] [blame]238<h2>Examples of using Clang</h2>
239
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]240<!-- Thanks to
241 http://shiflett.org/blog/2006/oct/formatting-and-highlighting-php-code-listings
242Site suggested using pre in CSS, but doesn't work in IE, so went for the <pre>
243tag. -->
244
245<pre class="code">
246$ <b>cat ~/t.c</b>
247typedef float V __attribute__((vector_size(16)));
248V foo(V a, V b) { return a+b*a; }
249</pre>
250
251
Ted Kremenek77251e92008-06-17 13:48:36 +0000[diff] [blame]252<h3>Preprocessing:</h3>
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]253
254<pre class="code">
255$ <b>clang ~/t.c -E</b>
256# 1 "/Users/sabre/t.c" 1
257
258typedef float V __attribute__((vector_size(16)));
259
260V foo(V a, V b) { return a+b*a; }
261</pre>
262
263
Ted Kremenek77251e92008-06-17 13:48:36 +0000[diff] [blame]264<h3>Type checking:</h3>
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]265
266<pre class="code">
267$ <b>clang -fsyntax-only ~/t.c</b>
268</pre>
269
270
Ted Kremenek77251e92008-06-17 13:48:36 +0000[diff] [blame]271<h3>GCC options:</h3>
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]272
273<pre class="code">
274$ <b>clang -fsyntax-only ~/t.c -pedantic</b>
Benjamin Kramereaa262b2012-01-15 15:26:07 +0000[diff] [blame]275/Users/sabre/t.c:2:17: <span style="color:magenta">warning:</span> extension used
276<span style="color:darkgreen">typedef float V __attribute__((vector_size(16)));</span>
277<span style="color:blue"> ^</span>
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]2781 diagnostic generated.
279</pre>
280
281
Ted Kremenek77251e92008-06-17 13:48:36 +0000[diff] [blame]282<h3>Pretty printing from the AST:</h3>
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]283
Sylvestre Ledru830885c2012-07-23 08:59:39 +0000[diff] [blame]284<p>Note, the <tt>-cc1</tt> argument indicates the compiler front-end, and
Daniel Dunbar520d1e62009-12-11 23:04:35 +0000[diff] [blame]285not the driver, should be run. The compiler front-end has several additional
286Clang specific features which are not exposed through the GCC compatible driver
287interface.</p>
288
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]289<pre class="code">
Daniel Dunbar520d1e62009-12-11 23:04:35 +0000[diff] [blame]290$ <b>clang -cc1 ~/t.c -ast-print</b>
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]291typedef float V __attribute__(( vector_size(16) ));
292V foo(V a, V b) {
293 return a + b * a;
294}
295</pre>
296
297
Ted Kremenek77251e92008-06-17 13:48:36 +0000[diff] [blame]298<h3>Code generation with LLVM:</h3>
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]299
300<pre class="code">
Daniel Dunbar520d1e62009-12-11 23:04:35 +0000[diff] [blame]301$ <b>clang ~/t.c -S -emit-llvm -o -</b>
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]302define &lt;4 x float&gt; @foo(&lt;4 x float&gt; %a, &lt;4 x float&gt; %b) {
303entry:
304 %mul = mul &lt;4 x float&gt; %b, %a
305 %add = add &lt;4 x float&gt; %mul, %a
306 ret &lt;4 x float&gt; %add
307}
Daniel Dunbar520d1e62009-12-11 23:04:35 +0000[diff] [blame]308$ <b>clang -fomit-frame-pointer -O3 -S -o - t.c</b> <i># On x86_64</i>
309...
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]310_foo:
Daniel Dunbar520d1e62009-12-11 23:04:35 +0000[diff] [blame]311Leh_func_begin1:
312 mulps %xmm0, %xmm1
313 addps %xmm1, %xmm0
314 ret
315Leh_func_end1:
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]316</pre>
317
Eric Christopher2dc30a52008-02-08 06:45:49 +0000[diff] [blame]318</div>
319</body>
320</html>