</head>
<body>
-<div class="doc_title">
+<h1>
Getting Started with the LLVM System
-</div>
+</h1>
<ul>
<li><a href="#overview">Overview</a>
<li><a href="#unpack">Unpacking the LLVM Archives</a></li>
<li><a href="#checkout">Checkout LLVM from Subversion</a></li>
<li><a href="#git_mirror">LLVM GIT mirror</a></li>
- <li><a href="#installcf">Install the GCC Front End</a></li>
<li><a href="#config">Local LLVM Configuration</a></li>
<li><a href="#compile">Compiling the LLVM Suite Source Code</a></li>
<li><a href="#cross-compile">Cross-Compiling LLVM</a></li>
<li><a href="#tutorial">An Example Using the LLVM Tool Chain</a>
<ol>
- <li><a href="#tutorial4">Example with llvm-gcc4</a></li>
+ <li><a href="#tutorial4">Example with Clang</a></li>
</ol>
<li><a href="#problems">Common Problems</a>
<li><a href="#links">Links</a>
<p>Written by:
<a href="mailto:criswell@uiuc.edu">John Criswell</a>,
<a href="mailto:sabre@nondot.org">Chris Lattner</a>,
- <a href="http://misha.brukman.net">Misha Brukman</a>,
+ <a href="http://misha.brukman.net/">Misha Brukman</a>,
<a href="http://www.cs.uiuc.edu/~vadve">Vikram Adve</a>, and
<a href="mailto:gshi1@uiuc.edu">Guochun Shi</a>.
</p>
<!-- *********************************************************************** -->
-<div class="doc_section">
- <a name="overview"><b>Overview</b></a>
-</div>
+<h2>
+ <a name="overview">Overview</a>
+</h2>
<!-- *********************************************************************** -->
-<div class="doc_text">
+<div>
<p>Welcome to LLVM! In order to get started, you first need to know some
basic information.</p>
<p>First, LLVM comes in three pieces. The first piece is the LLVM
suite. This contains all of the tools, libraries, and header files
-needed to use the low level virtual machine. It contains an
-assembler, disassembler, bitcode analyzer and bitcode optimizer. It
-also contains basic regression tests that can be used to test the LLVM
-tools and the GCC front end.</p>
-
-<p>The second piece is the GCC front end. This component provides a version of
-GCC that compiles C and C++ code into LLVM bitcode. Currently, the GCC front
-end uses the GCC parser to convert code to LLVM. Once
-compiled into LLVM bitcode, a program can be manipulated with the LLVM tools
-from the LLVM suite.</p>
+needed to use LLVM. It contains an assembler, disassembler, bitcode
+analyzer and bitcode optimizer. It also contains basic regression tests that
+can be used to test the LLVM tools and the Clang front end.</p>
+
+<p>The second piece is the <a href="http://clang.llvm.org/">Clang</a> front end.
+This component compiles C, C++, Objective C, and Objective C++ code into LLVM
+bitcode. Once compiled into LLVM bitcode, a program can be manipulated with the
+LLVM tools from the LLVM suite.
+</p>
<p>
There is a third, optional piece called Test Suite. It is a suite of programs
</div>
<!-- *********************************************************************** -->
-<div class="doc_section">
- <a name="quickstart"><b>Getting Started Quickly (A Summary)</b></a>
-</div>
+<h2>
+ <a name="quickstart">Getting Started Quickly (A Summary)</a>
+</h2>
<!-- *********************************************************************** -->
-<div class="doc_text">
+<div>
+
+<p>The LLVM Getting Started documentation may be out of date. So, the Clang
+<a href="http://clang.llvm.org/get_started.html">Getting Started</a> page might
+also be a good place to start.</p>
<p>Here's the short story for getting up and running quickly with LLVM:</p>
<li>Read the documentation.</li>
<li>Read the documentation.</li>
<li>Remember that you were warned twice about reading the documentation.</li>
- <li>Install the llvm-gcc-4.2 front end if you intend to compile C or C++
- (see <a href="#installcf">Install the GCC Front End</a> for details):</li>
- <ol>
- <li><tt>cd <i>where-you-want-the-C-front-end-to-live</i></tt></li>
- <li><tt>gunzip --stdout llvm-gcc-4.2-<i>version</i>-<i>platform</i>.tar.gz | tar -xvf -</tt></li>
- <li><tt><i>install-binutils-binary-from-MinGW</i></tt> (Windows only)</li>
- <li>Note: If the binary extension is "<tt>.bz</tt>" use <tt>bunzip2</tt> instead of <tt>gunzip</tt>.</li>
- <li>Note: On Windows, use <a href="http://www.7-zip.org">7-Zip</a> or a similar archiving tool.</li>
- <li>Add <tt>llvm-gcc</tt>'s "<tt>bin</tt>" directory to your <tt>PATH</tt> environment variable.</li>
- </ol></li>
- <li>Get the LLVM Source Code
+ <li>Checkout LLVM:
<ul>
- <li>With the distributed files (or use <a href="#checkout">SVN</a>):
- <ol>
- <li><tt>cd <i>where-you-want-llvm-to-live</i></tt>
- <li><tt>gunzip --stdout llvm-<i>version</i>.tar.gz | tar -xvf -</tt>
- </ol></li>
-
- </ul></li>
+ <li><tt>cd <i>where-you-want-llvm-to-live</i></tt>
+ <li><tt>svn co http://llvm.org/svn/llvm-project/llvm/trunk llvm</tt></li>
+ </ul>
+ </li>
- <li><b>[Optional]</b> Get the Test Suite Source Code
+ <li>Checkout Clang:
<ul>
- <li>With the distributed files (or use <a href="#checkout">SVN</a>):
- <ol>
- <li><tt>cd <i>where-you-want-llvm-to-live</i></tt>
- <li><tt>cd llvm/projects</tt>
- <li><tt>gunzip --stdout llvm-test-<i>version</i>.tar.gz | tar -xvf -</tt>
- <li><tt>mv llvm-test-<i>version</i> test-suite</tt>
- </ol></li>
+ <li><tt>cd <i>where-you-want-llvm-to-live</i></tt>
+ <li><tt>cd llvm/tools</tt>
+ <li><tt>svn co http://llvm.org/svn/llvm-project/cfe/trunk clang</tt></li>
+ </ul>
+ </li>
- </ul></li>
+ <li>Checkout Compiler-RT:
+ <ul>
+ <li><tt>cd <i>where-you-want-llvm-to-live</i></tt>
+ <li><tt>cd llvm/projects</tt>
+ <li><tt>svn co http://llvm.org/svn/llvm-project/compiler-rt/trunk
+ compiler-rt</tt></li>
+ </ul>
+ </li>
+ <li>Get the Test Suite Source Code <b>[Optional]</b>
+ <ul>
+ <li><tt>cd <i>where-you-want-llvm-to-live</i></tt>
+ <li><tt>cd llvm/projects</tt>
+ <li><tt>svn co http://llvm.org/svn/llvm-project/test-suite/trunk test-suite</tt></li>
+ </ul>
+ </li>
- <li>Configure the LLVM Build Environment
- <ol>
+ <li>Configure and build LLVM and Clang:
+ <ul>
<li><tt>cd <i>where-you-want-to-build-llvm</i></tt></li>
- <li><tt><i>/path/to/llvm/</i>configure [options]</tt><br>
- Some common options:
+ <li><tt>mkdir build</tt> (for building without polluting the source dir)</li>
+ <li><tt>cd build</tt></li>
+ <li><tt>../llvm/configure [options]</tt>
+ <br>Some common options:
<ul>
- <li><tt>--prefix=<i>directory</i></tt>
- <p>Specify for <i>directory</i> the full pathname of where you
+ <li><tt>--prefix=<i>directory</i></tt> -
+ Specify for <i>directory</i> the full pathname of where you
want the LLVM tools and libraries to be installed (default
- <tt>/usr/local</tt>).</p></li>
- <li><tt>--with-llvmgccdir=<i>directory</i></tt>
- <p>Optionally, specify for <i>directory</i> the full pathname of the
- C/C++ front end installation to use with this LLVM configuration. If
- not specified, the PATH will be searched. This is only needed if you
- want to run test-suite or do some special kinds of LLVM builds.</p></li>
- <li><tt>--enable-spec2000=<i>directory</i></tt>
- <p>Enable the SPEC2000 benchmarks for testing. The SPEC2000
- benchmarks should be available in
- <tt><i>directory</i></tt>.</p></li>
+ <tt>/usr/local</tt>).</li>
</ul>
- </ol></li>
- <li>Build the LLVM Suite:
- <ol>
- <li><tt>gmake -k |& tee gnumake.out
- # this is csh or tcsh syntax</tt></li>
- <li>If you get an "internal compiler error (ICE)" or test failures, see
- <a href="#brokengcc">below</a>.</li>
- </ol>
+ <ul>
+ <li><tt>--enable-optimized</tt> -
+ Compile with optimizations enabled (default is NO).</li>
+ </ul>
+
+ <ul>
+ <li><tt>--enable-assertions</tt> -
+ Compile with assertion checks enabled (default is YES).</li>
+ </ul>
+ </li>
+ <li><tt>make [-j]</tt> - The -j specifies the number of jobs (commands) to
+ run simultaneously. This builds both LLVM and Clang for Debug+Asserts mode.
+ The --enabled-optimized configure option is used to specify a Release build.</li>
+ <li><tt>make check-all</tt> -
+ This run the regression tests to ensure everything is in working order.</li>
+ <li><tt>make update</tt> -
+ This command is used to update all the svn repositories at once, rather then
+ having to <tt>cd</tt> into the individual repositories and running
+ <tt>svn update</tt>.</li>
+ <li>It is also possible to use CMake instead of the makefiles. With CMake
+ it is also possible to generate project files for several IDEs: Eclipse
+ CDT4, CodeBlocks, Qt-Creator (use the CodeBlocks generator), KDevelop3.</li>
+ <li>If you get an "internal compiler error (ICE)" or test failures, see
+ <a href="#brokengcc">below</a>.</li>
+
+ </ul>
+ </li>
</ol>
<p>Consult the <a href="#starting">Getting Started with LLVM</a> section for
detailed information on configuring and compiling LLVM. See <a
href="#environment">Setting Up Your Environment</a> for tips that simplify
-working with the
GCC front end and LLVM tools. Go to <a href="#layout">Program
+working with the
Clang front end and LLVM tools. Go to <a href="#layout">Program
Layout</a> to learn about the layout of the source code tree.</p>
</div>
<!-- *********************************************************************** -->
-<div class="doc_section">
- <a name="requirements"><b>Requirements</b></a>
-</div>
+<h2>
+ <a name="requirements">Requirements</a>
+</h2>
<!-- *********************************************************************** -->
-<div class="doc_text">
+<div>
<p>Before you begin to use the LLVM system, review the requirements given below.
This may save you some trouble by knowing ahead of time what hardware and
software you will need.</p>
-</div>
-
<!-- ======================================================================= -->
-<div class="doc_subsection">
- <a name="hardware"><b>Hardware</b></a>
-</div>
+<h3>
+ <a name="hardware">Hardware</a>
+</h3>
-<div class="doc_text">
+<div>
<p>LLVM is known to work on the following platforms:</p>
<tr>
<td>Windows</td>
<td>x86<sup><a href="#pf_1">1</a></sup></td>
- <td>Visual Studio 200
5 SP1 or higher<sup><a href="#pf_4">4</a>,<a href="#pf_5">5</a></sup></td>
+ <td>Visual Studio 200
8 or higher<sup><a href="#pf_4">4</a>,<a href="#pf_5">5</a></sup></td>
<tr>
<td>AIX<sup><a href="#pf_3">3</a>,<a href="#pf_4">4</a></sup></td>
<td>PowerPC</td>
ActivePerl, as these have Windows-specifics that will cause the
build to fail.</a></li>
<li><a name="pf_11">To use LLVM modules on Win32-based system,
- you may configure LLVM with <i>"--enable-shared"</i>.</li>
+ you may configure LLVM with <i>"--enable-shared"</i>.</a></li>
<li><a name="pf_12">To compile SPU backend, you need to add
- <tt>"LDFLAGS=-Wl,--stack,16777216"</tt> to configure.</li>
+ <tt>"LDFLAGS=-Wl,--stack,16777216"</tt> to configure.</a></li>
</ol>
</div>
generation should work as well, although the generated native code may not work
on your platform.</p>
-<p>The GCC front end is not very portable at the moment. If you want to get it
-to work on another platform, you can download a copy of the source and <a
-href="GCCFEBuildInstrs.html">try to compile it</a> on your platform.</p>
-
</div>
<!-- ======================================================================= -->
-<div class="doc_subsection"><a name="software"><b>Software</b></a></div>
-<div class="doc_text">
+<h3>
+ <a name="software">Software</a>
+</h3>
+<div>
<p>Compiling LLVM requires that you have several software packages
installed. The table below lists those required packages. The Package column
is the usual name for the software package that LLVM depends on. The Version
</tr>
<tr>
- <td><a href="http://gcc.gnu.org">GCC</a></td>
+ <td><a href="http://gcc.gnu.org/">GCC</a></td>
<td>3.4.2</td>
<td>C/C++ compiler<sup><a href="#sf1">1</a></sup></td>
</tr>
<tr>
- <td><a href="http://www.gnu.org/software/texinfo">TeXinfo</a></td>
+ <td><a href="http://www.gnu.org/software/texinfo/">TeXinfo</a></td>
<td>4.5</td>
<td>For building the CFE</td>
</tr>
<tr>
<td><a href="http://www.perl.com/download.csp">perl</a></td>
<td>≥5.6.0</td>
- <td>Nightly tester, utilities</td>
+ <td>Utilities</td>
</tr>
<tr>
</tr>
<tr>
- <td><a href="http://www.gnu.org/software/autoconf">GNU Autoconf</a></td>
+ <td><a href="http://www.gnu.org/software/autoconf/">GNU Autoconf</a></td>
<td>2.60</td>
<td>Configuration script builder<sup><a href="#sf4">4</a></sup></td>
</tr>
<tr>
- <td><a href="http://www.gnu.org/software/automake">GNU Automake</a></td>
+ <td><a href="http://www.gnu.org/software/automake/">GNU Automake</a></td>
<td>1.9.6</td>
<td>aclocal macro generator<sup><a href="#sf4">4</a></sup></td>
</tr>
</div>
<!-- ======================================================================= -->
-<div class="doc_subsection">
+<h3>
<a name="brokengcc">Broken versions of GCC and other tools</a>
-</div>
+</h3>
-<div class="doc_text">
+<div>
<p>LLVM is very demanding of the host C++ compiler, and as such tends to expose
bugs in the compiler. In particular, several versions of GCC crash when trying
-to compile LLVM. We routinely use GCC 3.3.3, 3.4.0, and Apple 4.0.1
-successfully with them (however, see important notes below). Other versions
-of GCC will probably work as well. GCC versions listed
+to compile LLVM. We routinely use GCC 4.2 (and higher) or Clang.
+Other versions of GCC will probably work as well. GCC versions listed
here are known to not work. If you are using one of these versions, please try
to upgrade your GCC to something more recent. If you run into a problem with a
version of GCC not listed here, please <a href="mailto:llvmdev@cs.uiuc.edu">let
the "<tt>convert_from_eh_region_ranges_1</tt>" GCC function.</p>
<p><b>Cygwin GCC 3.3.3</b>: The version of GCC 3.3.3 commonly shipped with
- Cygwin does not work. Please <a href="GCCFEBuildInstrs.html#cygwin">upgrade
- to a newer version</a> if possible.</p>
+ Cygwin does not work.</p>
<p><b>SuSE GCC 3.3.3</b>: The version of GCC 3.3.3 shipped with SuSE 9.1 (and
possibly others) does not compile LLVM correctly (it appears that exception
handling is broken in some cases). Please download the FSF 3.3.3 or upgrade
</div>
-
+</div>
<!-- *********************************************************************** -->
-<div class="doc_section">
- <a name="starting"><b>Getting Started with LLVM</b></a>
-</div>
+<h2>
+ <a name="starting">Getting Started with LLVM</a>
+</h2>
<!-- *********************************************************************** -->
-<div class="doc_text">
+<div>
<p>The remainder of this guide is meant to get you up and running with
LLVM and to give you some basic information about the LLVM environment.</p>
href="#tutorial">simple example</a> using the LLVM tool chain, and <a
href="#links">links</a> to find more information about LLVM or to get
help via e-mail.</p>
-</div>
<!-- ======================================================================= -->
-<div class="doc_subsection">
+<h3>
<a name="terminology">Terminology and Notation</a>
-</div>
+</h3>
-<div class="doc_text">
+<div>
<p>Throughout this manual, the following names are used to denote paths
specific to the local system and working environment. <i>These are not
can be the same as SRC_ROOT).
<br><br>
- <dt>LLVMGCCDIR
- <dd>
- This is where the LLVM GCC Front End is installed.
- <p>
- For the pre-built GCC front end binaries, the LLVMGCCDIR is
- <tt>llvm-gcc/<i>platform</i>/llvm-gcc</tt>.
</dl>
</div>
<!-- ======================================================================= -->
-<div class="doc_subsection">
+<h3>
<a name="environment">Setting Up Your Environment</a>
-</div>
+</h3>
-<div class="doc_text">
+<div>
<p>
In order to compile and use LLVM, you may need to set some environment
</div>
<!-- ======================================================================= -->
-<div class="doc_subsection">
+<h3>
<a name="unpack">Unpacking the LLVM Archives</a>
-</div>
+</h3>
-<div class="doc_text">
+<div>
<p>
If you have the LLVM distribution, you will need to unpack it before you
</div>
<!-- ======================================================================= -->
-<div class="doc_subsection">
+<h3>
<a name="checkout">Checkout LLVM from Subversion</a>
-</div>
+</h3>
-<div class="doc_text">
+<div>
<p>If you have access to our Subversion repository, you can get a fresh copy of
the entire source code. All you need to do is check it out from Subversion as
configured by the LLVM configure script as well as automatically updated when
you run <tt>svn update</tt>.</p>
-<p>If you would like to get the GCC front end source code, you can also get it
-and build it yourself. Please follow <a href="GCCFEBuildInstrs.html">these
-instructions</a> to successfully get and build the LLVM GCC front-end.</p>
-
</div>
<!-- ======================================================================= -->
-<div class="doc_subsection">
+<h3>
<a name="git_mirror">GIT mirror</a>
-</div>
+</h3>
-<div class="doc_text">
+<div>
<p>GIT mirrors are available for a number of LLVM subprojects. These mirrors
sync automatically with each Subversion commit and contain all necessary
git-svn marks (so, you can recreate git-svn metadata locally). Note that right
now mirrors reflect only <tt>trunk</tt> for each project. You can do the
- read-only GIT clone of LLVM via:
-<pre>
-% git clone http://llvm.org/git/llvm.git
+ read-only GIT clone of LLVM via:</p>
+
+<pre class="doc_code">
+git clone http://llvm.org/git/llvm.git
+</pre>
+
+<p>If you want to check out clang too, run:</p>
+
+<pre class="doc_code">
+git clone http://llvm.org/git/llvm.git
+cd llvm/tools
+git clone http://llvm.org/git/clang.git
</pre>
+
+<p>
+Since the upstream repository is in Subversion, you should use
+<tt>"git pull --rebase"</tt>
+instead of <tt>"git pull"</tt> to avoid generating a non-linear
+history in your clone.
+To configure <tt>"git pull"</tt> to pass <tt>--rebase</tt> by default
+on the master branch, run the following command:
</p>
-</div>
+<pre class="doc_code">
+git config branch.master.rebase true
+</pre>
-<!-- ======================================================================= -->
-<div class="doc_subsection">
- <a name="installcf">Install the GCC Front End</a>
-</div>
+<h4>Sending patches with Git</h4>
+<div>
+<p>
+Please read <a href="DeveloperPolicy.html#patches">Developer Policy</a>, too.
+</p>
+
+<p>
+Assume <tt>master</tt> points the upstream and <tt>mybranch</tt> points your
+working branch, and <tt>mybranch</tt> is rebased onto <tt>master</tt>.
+At first you may check sanity of whitespaces:
+</p>
+
+<pre class="doc_code">
+git diff --check master..mybranch
+</pre>
-<div class="doc_text">
+<p>
+The easiest way to generate a patch is as below:
+</p>
-<p>Before configuring and compiling the LLVM suite (or if you want to use just the LLVM
-GCC front end) you can optionally extract the front end from the binary distribution.
-It is used for running the LLVM test-suite and for compiling C/C++ programs. Note that
-you can optionally <a href="GCCFEBuildInstrs.html">build llvm-gcc yourself</a> after building the
-main LLVM repository.</p>
+<pre class="doc_code">
+git diff master..mybranch > /path/to/mybranch.diff
+</pre>
-<p>To install the GCC front end, do the following (on Windows, use an archival tool
-like <a href="http://www.7-zip.org">7-zip</a> that understands gzipped tars):</p>
+<p>
+It is a little different from svn-generated diff. git-diff-generated diff has
+prefixes like <tt>a/</tt> and <tt>b/</tt>. Don't worry, most developers might
+know it could be accepted with <tt>patch -p1 -N</tt>.
+</p>
-<ol>
- <li><tt>cd <i>where-you-want-the-front-end-to-live</i></tt></li>
- <li><tt>gunzip --stdout llvm-gcc-4.2-<i>version</i>-<i>platform</i>.tar.gz | tar -xvf
- -</tt></li>
-</ol>
+<p>
+But you may generate patchset with git-format-patch. It generates
+by-each-commit patchset. To generate patch files to attach to your article:
+</p>
+
+<pre class="doc_code">
+git format-patch --no-attach master..mybranch -o /path/to/your/patchset
+</pre>
+
+<p>
+If you would like to send patches directly, you may use git-send-email or
+git-imap-send. Here is an example to generate the patchset in Gmail's [Drafts].
+</p>
+
+<pre class="doc_code">
+git format-patch --attach master..mybranch --stdout | git imap-send
+</pre>
-<p>Once the binary is uncompressed, if you're using a *nix-based system, add a symlink for
-<tt>llvm-gcc</tt> and <tt>llvm-g++</tt> to some directory in your path. If you're using a
-Windows-based system, add the <tt>bin</tt> subdirectory of your front end installation directory
-to your <tt>PATH</tt> environment variable. For example, if you uncompressed the binary to
-<tt>c:\llvm-gcc</tt>, add <tt>c:\llvm-gcc\bin</tt> to your <tt>PATH</tt>.</p>
-
-<p>If you now want to build LLVM from source, when you configure LLVM, it will
-automatically detect <tt>llvm-gcc</tt>'s presence (if it is in your path) enabling its
-use in test-suite. Note that you can always build or install <tt>llvm-gcc</tt> at any
-point after building the main LLVM repository: just reconfigure llvm and
-test-suite will pick it up.
+<p>
+Then, your .git/config should have [imap] sections.
</p>
-<p>As a convenience for Windows users, the front end binaries for MinGW/x86 include
-versions of the required w32api and mingw-runtime binaries. The last remaining step for
-Windows users is to simply uncompress the binary binutils package from
-<a href="http://mingw.org/">MinGW</a> into your front end installation directory. While the
-front end installation steps are not quite the same as a typical manual MinGW installation,
-they should be similar enough to those who have previously installed MinGW on Windows systems.</p>
+<pre class="doc_code">
+[imap]
+ host = imaps://imap.gmail.com
+ user = <em>your.gmail.account</em>@gmail.com
+ pass = <em>himitsu!</em>
+ port = 993
+ sslverify = false
+; in English
+ folder = "[Gmail]/Drafts"
+; example for Japanese, "Modified UTF-7" encoded.
+ folder = "[Gmail]/&Tgtm+DBN-"
+; example for Traditional Chinese
+ folder = "[Gmail]/&g0l6Pw-"
+</pre>
+
+</div>
-<p>To install binutils on Windows:</p>
+<h4>For developers to work with git-svn</h4>
+<div>
+
+<p>To set up clone from which you can submit code using
+ <tt>git-svn</tt>, run:</p>
+
+<pre class="doc_code">
+git clone http://llvm.org/git/llvm.git
+cd llvm
+git svn init https://llvm.org/svn/llvm-project/llvm/trunk --username=<username>
+git config svn-remote.svn.fetch :refs/remotes/origin/master
+git svn rebase -l # -l avoids fetching ahead of the git mirror.
+
+# If you have clang too:
+cd tools
+git clone http://llvm.org/git/clang.git
+cd clang
+git svn init https://llvm.org/svn/llvm-project/cfe/trunk --username=<username>
+git config svn-remote.svn.fetch :refs/remotes/origin/master
+git svn rebase -l
+</pre>
-<ol>
- <li><tt><i>download GNU Binutils from <a href="http://sourceforge.net/projects/mingw/files/">MinGW Downloads</a></i></tt></li>
- <li><tt>cd <i>where-you-uncompressed-the-front-end</i></tt></li>
- <li><tt><i>uncompress archived binutils directories (not the tar file) into the current directory</i></tt></li>
-</ol>
+<p>To update this clone without generating git-svn tags that conflict
+with the upstream git repo, run:</p>
-<p>The binary versions of the LLVM GCC front end may not suit all of your needs. For
-example, the binary distribution may include an old version of a system header
-file, not "fix" a header file that needs to be fixed for GCC, or it may be linked with
-libraries not available on your system. In cases like these, you may want to try
-<a href="GCCFEBuildInstrs.html">building the GCC front end from source</a>. Thankfully,
-this is much easier now than it was in the past.</p>
+<pre class="doc_code">
+git fetch && (cd tools/clang && git fetch) # Get matching revisions of both trees.
+git checkout master
+git svn rebase -l
+(cd tools/clang &&
+ git checkout master &&
+ git svn rebase -l)
+</pre>
+
+<p>This leaves your working directories on their master branches, so
+you'll need to <tt>checkout</tt> each working branch individually and
+<tt>rebase</tt> it on top of its parent branch. (Note: This script is
+intended for relative newbies to git. If you have more experience,
+you can likely improve on it.)</p>
-<p>We also do not currently support updating of the GCC front end by manually overlaying
-newer versions of the w32api and mingw-runtime binary packages that may become available
-from MinGW. At this time, it's best to think of the MinGW LLVM GCC front end binary as
-a self-contained convenience package that requires Windows users to simply download and
-uncompress the GNU Binutils binary package from the MinGW project.</p>
+<p>The git-svn metadata can get out of sync after you mess around with
+branches and <code>dcommit</code>. When that happens, <code>git svn
+dcommit</code> stops working, complaining about files with uncommitted
+changes. The fix is to rebuild the metadata:</p>
+
+<pre class="doc_code">
+rm -rf .git/svn
+git svn rebase -l
+</pre>
-<p>Regardless of your platform, if you discover that installing the LLVM GCC front end
-binaries is not as easy as previously described, or you would like to suggest improvements,
-please let us know how you would like to see things improved by dropping us a note on our
-<a href="http://llvm.org/docs/#maillist">mailing list</a>.</p>
+</div>
</div>
<!-- ======================================================================= -->
-<div class="doc_subsection">
+<h3>
<a name="config">Local LLVM Configuration</a>
-</div>
+</h3>
-<div class="doc_text">
+<div>
<p>Once checked out from the Subversion repository, the LLVM suite source
code must be
<p>The following options can be used to set or enable LLVM specific options:</p>
<dl>
- <dt><i>--with-llvmgccdir</i></dt>
- <dd>Path to the LLVM C/C++ FrontEnd to be used with this LLVM configuration.
- The value of this option should specify the full pathname of the C/C++ Front
- End to be used. If this option is not provided, the PATH will be searched for
- a program named <i>llvm-gcc</i> and the C/C++ FrontEnd install directory will
- be inferred from the path found. If the option is not given, and no llvm-gcc
- can be found in the path then a warning will be produced by
- <tt>configure</tt> indicating this situation. LLVM may still be built with
- the <tt>tools-only</tt> target but attempting to build the runtime libraries
- will fail as these libraries require llvm-gcc and llvm-g++. See
- <a href="#installcf">Install the GCC Front End</a> for details on installing
- the C/C++ Front End. See
- <a href="GCCFEBuildInstrs.html">Bootstrapping the LLVM C/C++ Front-End</a>
- for details on building the C/C++ Front End.</dd>
- <dt><i>--with-tclinclude</i></dt>
- <dd>Path to the tcl include directory under which <tt>tclsh</tt> can be
- found. Use this if you have multiple tcl installations on your machine and you
- want to use a specific one (8.x) for LLVM. LLVM only uses tcl for running the
- dejagnu based test suite in <tt>llvm/test</tt>. If you don't specify this
- option, the LLVM configure script will search for the tcl 8.4 and 8.3
- releases.
- <br><br>
- </dd>
<dt><i>--enable-optimized</i></dt>
<dd>
Enables optimized compilation (debugging symbols are removed
selected as the target of the build host. You can also specify a comma
separated list of target names that you want available in llc. The target
names use all lower case. The current set of targets is: <br>
- <tt>alpha, ia64, powerpc, skeleton, sparc, x86</tt>.
+ <tt>arm, cbe, cpp, hexagon, mblaze, mips, mipsel, msp430, powerpc, ptx, sparc, spu, x86, x86_64, xcore</tt>.
<br><br></dd>
<dt><i>--enable-doxygen</i></dt>
<dd>Look for the doxygen program and enable construction of doxygen based
</div>
<!-- ======================================================================= -->
-<div class="doc_subsection">
+<h3>
<a name="compile">Compiling the LLVM Suite Source Code</a>
-</div>
+</h3>
-<div class="doc_text">
+<div>
<p>Once you have configured LLVM, you can build it. There are three types of
builds:</p>
</div>
<!-- ======================================================================= -->
-<div class="doc_subsection">
+<h3>
<a name="cross-compile">Cross-Compiling LLVM</a>
-</div>
+</h3>
-<div class="doc_text">
+<div>
<p>It is possible to cross-compile LLVM itself. That is, you can create LLVM
executables and libraries to be hosted on a platform different from the
platform where they are build (a Canadian Cross build). To configure a
</div>
<!-- ======================================================================= -->
-<div class="doc_subsection">
+<h3>
<a name="objfiles">The Location of LLVM Object Files</a>
-</div>
+</h3>
-<div class="doc_text">
+<div>
<p>The LLVM build system is capable of sharing a single LLVM source tree among
several LLVM builds. Hence, it is possible to build LLVM for several different
</div>
<!-- ======================================================================= -->
-<div class="doc_subsection">
+<h3>
<a name="optionalconfig">Optional Configuration Items</a>
-</div>
+</h3>
-<div class="doc_text">
+<div>
<p>
If you're running on a Linux system that supports the "<a
<p>
This allows you to execute LLVM bitcode files directly. On Debian, you
-can also use this command instead of the 'echo' command above:</p>
+can also use this command instead of the 'echo' command above:
</p>
<div class="doc_code">
</div>
-<!-- *********************************************************************** -->
-<div class="doc_section">
- <a name="layout"><b>Program Layout</b></a>
</div>
+
+<!-- *********************************************************************** -->
+<h2>
+ <a name="layout">Program Layout</a>
+</h2>
<!-- *********************************************************************** -->
-<div class="doc_text">
+<div>
<p>One useful source of information about the LLVM source base is the LLVM <a
-href="http://www.doxygen.org">doxygen</a> documentation available at <tt><a
+href="http://www.doxygen.org
/">doxygen</a> documentation available at <tt><a
href="http://llvm.org/doxygen/">http://llvm.org/doxygen/</a></tt>.
The following is a brief introduction to code layout:</p>
-</div>
-
<!-- ======================================================================= -->
-<div class="doc_subsection"><a name="examples"><tt>llvm/examples</tt></a></div>
-<div class="doc_text">
+<h3>
+ <a name="examples"><tt>llvm/examples</tt></a>
+</h3>
+
+<div>
<p>This directory contains some simple examples of how to use the LLVM IR and
JIT.</p>
</div>
<!-- ======================================================================= -->
-<div class="doc_subsection"><a name="include"><tt>llvm/include</tt></a></div>
-<div class="doc_text">
+<h3>
+ <a name="include"><tt>llvm/include</tt></a>
+</h3>
+
+<div>
<p>This directory contains public header files exported from the LLVM
library. The three main subdirectories of this directory are:</p>
</div>
<!-- ======================================================================= -->
-<div class="doc_subsection"><a name="lib"><tt>llvm/lib</tt></a></div>
-<div class="doc_text">
+<h3>
+ <a name="lib"><tt>llvm/lib</tt></a>
+</h3>
+
+<div>
<p>This directory contains most of the source files of the LLVM system. In LLVM,
almost all code exists in libraries, making it very easy to share code among the
<dd> This directory contains files that describe various target architectures
for code generation. For example, the <tt>llvm/lib/Target/X86</tt>
directory holds the X86 machine description while
- <tt>llvm/lib/Target/CBackend</tt> implements the LLVM-to-C converter.</dd>
+ <tt>llvm/lib/Target/ARM</tt> implements the ARM backend.</dd>
<dt><tt><b>llvm/lib/CodeGen/</b></tt></dt>
<dd> This directory contains the major parts of the code generator: Instruction
at runtime in both interpreted and JIT compiled fashions.</dd>
<dt><tt><b>llvm/lib/Support/</b></tt></dt>
- <dd> This directory contains the source code that corresponds to the header
- files located in <tt>llvm/include/Support/</tt>.</dd>
-
- <!--FIXME: obsoleted -->
- <dt><tt><b>llvm/lib/System/</b></tt></dt>
- <dd>This directory contains the operating system abstraction layer that
- shields LLVM from platform-specific coding.</dd>
+ <dd> This directory contains the source code that corresponds to the header
+ files located in <tt>llvm/include/ADT/</tt>
+ and <tt>llvm/include/Support/</tt>.</dd>
</dl>
</div>
<!-- ======================================================================= -->
-<div class="doc_subsection"><a name="projects"><tt>llvm/projects</tt></a></div>
-<div class="doc_text">
+<h3>
+ <a name="projects"><tt>llvm/projects</tt></a>
+</h3>
+
+<div>
<p>This directory contains projects that are not strictly part of LLVM but are
shipped with LLVM. This is also the directory where you should create your own
LLVM-based projects. See <tt>llvm/projects/sample</tt> for an example of how
</div>
<!-- ======================================================================= -->
-<div class="doc_subsection"><a name="runtime"><tt>llvm/runtime</tt></a></div>
-<div class="doc_text">
+<h3>
+ <a name="runtime"><tt>llvm/runtime</tt></a>
+</h3>
+
+<div>
<p>This directory contains libraries which are compiled into LLVM bitcode and
-used when linking programs with the GCC front end. Most of these libraries are
+used when linking programs with the Clang front end. Most of these libraries are
skeleton versions of real libraries; for example, libc is a stripped down
version of glibc.</p>
</div>
<!-- ======================================================================= -->
-<div class="doc_subsection"><a name="test"><tt>llvm/test</tt></a></div>
-<div class="doc_text">
+<h3>
+ <a name="test"><tt>llvm/test</tt></a>
+</h3>
+
+<div>
<p>This directory contains feature and regression tests and other basic sanity
checks on the LLVM infrastructure. These are intended to run quickly and cover
a lot of territory without being exhaustive.</p>
</div>
<!-- ======================================================================= -->
-<div class="doc_subsection"><a name="test-suite"><tt>test-suite</tt></a></div>
-<div class="doc_text">
+<h3>
+ <a name="test-suite"><tt>test-suite</tt></a>
+</h3>
+
+<div>
<p>This is not a directory in the normal llvm module; it is a separate
Subversion
module that must be checked out (usually to <tt>projects/test-suite</tt>).
</div>
<!-- ======================================================================= -->
-<div class="doc_subsection"><a name="tools"><tt>llvm/tools</tt></a></div>
-<div class="doc_text">
+<h3>
+ <a name="tools"><tt>llvm/tools</tt></a>
+</h3>
+
+<div>
<p>The <b>tools</b> directory contains the executables built out of the
libraries above, which form the main part of the user interface. You can
href="HowToSubmitABug.html">HowToSubmitABug.html</a> for more information
on using <tt>bugpoint</tt>.</dd>
- <dt><tt><b>llvmc</b></tt></dt>
- <dd>The LLVM Compiler Driver. This program can
- be configured to utilize both LLVM and non-LLVM compilation tools to enable
- pre-processing, translation, optimization, assembly, and linking of programs
- all from one command line. <tt>llvmc</tt> also takes care of processing the
- dependent libraries found in bitcode. This reduces the need to get the
- traditional <tt>-l<name></tt> options right on the command line. Please
- note that this tool, while functional, is still experimental and not feature
- complete.</dd>
-
<dt><tt><b>llvm-ar</b></tt></dt>
<dd>The archiver produces an archive containing
the given LLVM bitcode files, optionally with an index for faster
<dt><tt><b>llvm-ld</b></tt></dt>
<dd><tt>llvm-ld</tt> is a general purpose and extensible linker for LLVM.
- This is the linker invoked by <tt>llvmc</tt>. It performs standard link time
- optimizations and allows optimization modules to be loaded and run so that
- language specific optimizations can be applied at link time.</dd>
+ It performs standard link time optimizations and allows optimization
+ modules to be loaded and run so that language specific optimizations can
+ be applied at link time.</dd>
<dt><tt><b>llvm-link</b></tt></dt>
<dd><tt>llvm-link</tt>, not surprisingly, links multiple LLVM modules into
</div>
<!-- ======================================================================= -->
-<div class="doc_subsection"><a name="utils"><tt>llvm/utils</tt></a></div>
-<div class="doc_text">
+<h3>
+ <a name="utils"><tt>llvm/utils</tt></a>
+</h3>
+
+<div>
<p>This directory contains utilities for working with LLVM source code, and some
of the utilities are actually required as part of the build process because they
directory, switch to directory <tt>llvm/tools/llc</tt> and build it,
causing a re-linking of LLC.<br><br>
- <dt><tt><b>NewNightlyTest.pl</b></tt> and
- <tt><b>NightlyTestTemplate.html</b></tt> <dd>These files are used in a
- cron script to generate nightly status reports of the functionality of
- tools, and the results can be seen by following the appropriate link on
- the <a href="http://llvm.org/">LLVM homepage</a>.<br><br>
-
<dt><tt><b>TableGen/</b></tt> <dd>The <tt>TableGen</tt> directory contains
the tool used to generate register descriptions, instruction set
descriptions, and even assemblers from common TableGen description
</div>
+</div>
+
<!-- *********************************************************************** -->
-<div class="doc_section">
+<h2>
<a name="tutorial">An Example Using the LLVM Tool Chain</a>
-</div>
+</h2>
<!-- *********************************************************************** -->
-<div class="doc_text">
-<p>This section gives an example of using LLVM. llvm-gcc3 is now obsolete,
-so we only include instructions for llvm-gcc4.
-</p>
-
-<p><b>Note:</b> The <i>gcc4</i> frontend's invocation is <b><i>considerably different</i></b>
-from the previous <i>gcc3</i> frontend. In particular, the <i>gcc4</i> frontend <b><i>does not</i></b>
-create bitcode by default: <i>gcc4</i> produces native code. As the example below illustrates,
-the '--emit-llvm' flag is needed to produce LLVM bitcode output. For <i>makefiles</i> and
-<i>configure</i> scripts, the CFLAGS variable needs '--emit-llvm' to produce bitcode
-output.</p>
-</div>
+<div>
+<p>This section gives an example of using LLVM with the Clang front end.</p>
<!-- ======================================================================= -->
-<div class="doc_subsection"><a name="tutorial4">Example with llvm-gcc4</a></div>
+<h3>
+ <a name="tutorial4">Example with clang</a>
+</h3>
-<div class="doc_text">
+<div>
<ol>
<li><p>First, create a simple C file, name it 'hello.c':</p>
<li><p>Next, compile the C file into a native executable:</p>
- <div class="doc_code"><pre>% llvm-gcc hello.c -o hello</pre></div>
+ <div class="doc_code"><pre>% clang hello.c -o hello</pre></div>
- <p>Note that llvm-gcc works just like GCC by default. The standard -S and
+ <p>Note that clang works just like GCC by default. The standard -S and
-c arguments work as usual (producing a native .s or .o file,
respectively).</p></li>
<li><p>Next, compile the C file into a LLVM bitcode file:</p>
<div class="doc_code">
- <pre>% llvm-gcc -O3 -emit-llvm hello.c -c -o hello.bc</pre></div>
+ <pre>% clang -O3 -emit-llvm hello.c -c -o hello.bc</pre></div>
<p>The -emit-llvm option can be used with the -S or -c options to emit an
LLVM ".ll" or ".bc" file (respectively) for the code. This allows you
to use the <a href="CommandGuide/index.html">standard LLVM tools</a> on
- the bitcode file.</p>
-
- <p>Unlike llvm-gcc3, llvm-gcc4 correctly responds to -O[0123] arguments.
- </p></li>
+ the bitcode file.</p></li>
<li><p>Run the program in both forms. To run the program, use:</p>
<div class="doc_code"><pre>% ./hello.native</pre></div>
- <p>Note that using llvm-gcc to compile directly to native code (i.e. when
+ <p>Note that using clang to compile directly to native code (i.e. when
the -emit-llvm option is not present) does steps 6/7/8 for you.</p>
</li>
</div>
+</div>
<!-- *********************************************************************** -->
-<div class="doc_section">
+<h2>
<a name="problems">Common Problems</a>
-</div>
+</h2>
<!-- *********************************************************************** -->
-<div class="doc_text">
+<div>
<p>If you are having problems building or using LLVM, or if you have any other
general questions about LLVM, please consult the <a href="FAQ.html">Frequently
</div>
<!-- *********************************************************************** -->
-<div class="doc_section">
+<h2>
<a name="links">Links</a>
-</div>
+</h2>
<!-- *********************************************************************** -->
-<div class="doc_text">
+<div>
<p>This document is just an <b>introduction</b> on how to use LLVM to do
some simple things... there are many more interesting and complicated things
<a href="mailto:sabre@nondot.org">Chris Lattner</a><br>
<a href="http://llvm.x10sys.com/rspencer/">Reid Spencer</a><br>
- <a href="http://llvm.org">The LLVM Compiler Infrastructure</a><br>
+ <a href="http://llvm.org/">The LLVM Compiler Infrastructure</a><br>
Last modified: $Date$
</address>
</body>
projects / oota-llvm.git / blobdiff