forked from OSchip/llvm-project
1543 lines
57 KiB
HTML
1543 lines
57 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
|
|
"http://www.w3.org/TR/html4/strict.dtd">
|
|
<html>
|
|
<head>
|
|
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
|
|
<title>Getting Started with LLVM System</title>
|
|
<link rel="stylesheet" href="llvm.css" type="text/css">
|
|
</head>
|
|
<body>
|
|
|
|
<div class="doc_title">
|
|
Getting Started with the LLVM System
|
|
</div>
|
|
|
|
<ul>
|
|
<li><a href="#overview">Overview</a>
|
|
<li><a href="#quickstart">Getting Started Quickly (A Summary)</a>
|
|
<li><a href="#requirements">Requirements</a>
|
|
<ol>
|
|
<li><a href="#hardware">Hardware</a>
|
|
<li><a href="#software">Software</a>
|
|
<li><a href="#brokengcc">Broken versions of GCC</a>
|
|
</ol></li>
|
|
|
|
<li><a href="#starting">Getting Started with LLVM</a>
|
|
<ol>
|
|
<li><a href="#terminology">Terminology and Notation</a>
|
|
<li><a href="#environment">Setting Up Your Environment</a>
|
|
<li><a href="#unpack">Unpacking the LLVM Archives</a>
|
|
<li><a href="#checkout">Checkout LLVM from CVS</a>
|
|
<li><a href="#installcf">Install the GCC Front End</a>
|
|
<li><a href="#config">Local LLVM Configuration</a>
|
|
<li><a href="#compile">Compiling the LLVM Suite Source Code</a>
|
|
<li><a href="#objfiles">The Location of LLVM Object Files</a>
|
|
<li><a href="#optionalconfig">Optional Configuration Items</a>
|
|
</ol></li>
|
|
|
|
<li><a href="#layout">Program layout</a>
|
|
<ol>
|
|
<li><a href="#cvsdir"><tt>CVS</tt> directories</a>
|
|
<li><a href="#examples"><tt>llvm/examples</tt></a>
|
|
<li><a href="#include"><tt>llvm/include</tt></a>
|
|
<li><a href="#lib"><tt>llvm/lib</tt></a>
|
|
<li><a href="#projects"><tt>llvm/projects</tt></a>
|
|
<li><a href="#runtime"><tt>llvm/runtime</tt></a>
|
|
<li><a href="#test"><tt>llvm/test</tt></a>
|
|
<li><a href="#llvmtest"><tt>llvm-test</tt></a>
|
|
<li><a href="#tools"><tt>llvm/tools</tt></a>
|
|
<li><a href="#utils"><tt>llvm/utils</tt></a>
|
|
<li><a href="#win32"><tt>llvm/win32</tt></a>
|
|
</ol></li>
|
|
|
|
<li><a href="#tutorial">An Example Using the LLVM Tool Chain</a>
|
|
<li><a href="#problems">Common Problems</a>
|
|
<li><a href="#links">Links</a>
|
|
</ul>
|
|
|
|
<div class="doc_author">
|
|
<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://www.cs.uiuc.edu/~vadve">Vikram Adve</a>, and
|
|
<a href="mailto:gshi1@uiuc.edu">Guochun Shi</a>.
|
|
</p>
|
|
</div>
|
|
|
|
|
|
<!-- *********************************************************************** -->
|
|
<div class="doc_section">
|
|
<a name="overview"><b>Overview</b></a>
|
|
</div>
|
|
<!-- *********************************************************************** -->
|
|
|
|
<div class="doc_text">
|
|
|
|
<p>Welcome to LLVM! In order to get started, you first need to know some
|
|
basic information.</p>
|
|
|
|
<p>First, LLVM comes in two 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, bytecode
|
|
analyzer, and bytecode optimizer. It also contains a test suite 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 bytecode. Currently, the GCC front
|
|
end is a modified version of GCC 3.4 (we track the GCC 3.4 development). Once
|
|
compiled into LLVM bytecode, a program can be manipulated with the LLVM tools
|
|
from the LLVM suite.</p>
|
|
|
|
<p>
|
|
There is a third, optional piece called llvm-test. It is a suite of programs
|
|
with a testing harness that can be used to further test LLVM's functionality
|
|
and performance.
|
|
</p>
|
|
|
|
</div>
|
|
|
|
<!-- *********************************************************************** -->
|
|
<div class="doc_section">
|
|
<a name="quickstart"><b>Getting Started Quickly (A Summary)</b></a>
|
|
</div>
|
|
<!-- *********************************************************************** -->
|
|
|
|
<div class="doc_text">
|
|
|
|
<p>Here's the short story for getting up and running quickly with LLVM:</p>
|
|
|
|
<ol>
|
|
<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 GCC front end if you intend to compile C or C++:
|
|
<ol>
|
|
<li><tt>cd <i>where-you-want-the-C-front-end-to-live</i></tt></li>
|
|
<li><tt>gunzip --stdout cfrontend.<i>platform</i>.tar.gz | tar -xvf -</tt>
|
|
</li>
|
|
<li><tt>cd cfrontend/<i>platform</i><br>
|
|
./fixheaders</tt></li>
|
|
<li>Add the cfrontend's "bin" directory to your PATH variable.</li>
|
|
</ol></li>
|
|
|
|
<li>Get the LLVM Source Code
|
|
<ul>
|
|
<li>With the distributed files (or use <a href="#checkout">CVS</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><b>[Optional]</b> Get the Test Suite Source Code
|
|
<ul>
|
|
<li>With the distributed files (or use <a href="#checkout">CVS</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>
|
|
</ol></li>
|
|
|
|
</ul></li>
|
|
|
|
|
|
<li>Configure the LLVM Build Environment
|
|
<ol>
|
|
<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:
|
|
|
|
<ul>
|
|
<li><tt>--prefix=<i>directory</i></tt>
|
|
<p>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.</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>
|
|
</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)" see <a href="#brokengcc">below</a>.</li>
|
|
</ol>
|
|
|
|
</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
|
|
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>
|
|
<!-- *********************************************************************** -->
|
|
|
|
<div class="doc_text">
|
|
|
|
<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>
|
|
|
|
<div class="doc_text">
|
|
|
|
<p>LLVM is known to work on the following platforms:</p>
|
|
|
|
<table cellpadding="3">
|
|
<tr>
|
|
<th>OS</th>
|
|
<th>Arch</th>
|
|
<th>Compilers</th>
|
|
</tr>
|
|
<tr>
|
|
<td>Linux</td>
|
|
<td>x86<sup><a href="#pf_1">1</a></sup></td>
|
|
<td>GCC</td>
|
|
</tr>
|
|
<tr>
|
|
<td>Solaris</td>
|
|
<td>V9 (Ultrasparc)</td>
|
|
<td>GCC</td>
|
|
</tr>
|
|
<tr>
|
|
<td>FreeBSD</td>
|
|
<td>x86<sup><a href="#pf_1">1</a></sup></td>
|
|
<td>GCC</td>
|
|
</tr>
|
|
<tr>
|
|
<td>MacOS X<sup><a href="#pf_2">2</a></sup></td>
|
|
<td>PowerPC</td>
|
|
<td>GCC</td>
|
|
</tr>
|
|
<tr>
|
|
<td>MacOS X<sup><a href="#pf_2">2</a></sup></td>
|
|
<td>x86</td>
|
|
<td>GCC</td>
|
|
|
|
</tr>
|
|
<tr>
|
|
<td>Cygwin/Win32</td>
|
|
<td>x86<sup><a href="#pf_1">1</a></sup></td>
|
|
<td>GCC 3.4.X, binutils 2.15</td>
|
|
</tr>
|
|
<tr>
|
|
<td>MinGW/Win32</td>
|
|
<td>x86<sup><a href="#pf_1">1</a>,<a href="#pf_6">6</a></sup></td>
|
|
<td>GCC 3.4.X, binutils 2.15</td>
|
|
</tr>
|
|
<tr>
|
|
<td>Linux</td>
|
|
<td>amd64<sup><a href="#pf_3">3</a></sup></td>
|
|
<td>GCC</td>
|
|
</tr>
|
|
</table>
|
|
|
|
<p>LLVM has partial support for the following platforms:</p>
|
|
|
|
<table>
|
|
<tr>
|
|
<th>OS</th>
|
|
<th>Arch</th>
|
|
<th>Compilers</th>
|
|
</tr>
|
|
<tr>
|
|
<td>Windows</td>
|
|
<td>x86<sup><a href="#pf_1">1</a></sup></td>
|
|
<td>Visual Studio .NET<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>
|
|
<td>GCC</td>
|
|
</tr>
|
|
<tr>
|
|
<td>Linux<sup><a href="#pf_3">3</a>,<a href="#pf_5">5</a></sup></td>
|
|
<td>PowerPC</td>
|
|
<td>GCC</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td>Linux<sup><a href="#pf_7">7</a></sup></td>
|
|
<td>Alpha</td>
|
|
<td>GCC</td>
|
|
</tr>
|
|
<tr>
|
|
<td>Linux<sup><a href="#pf_7">7</a></sup></td>
|
|
<td>Itanium (IA-64)</td>
|
|
<td>GCC</td>
|
|
</tr>
|
|
<tr>
|
|
<td>HP-UX<sup><a href="#pf_7">7</a></sup></td>
|
|
<td>Itanium (IA-64)</td>
|
|
<td>HP aCC</td>
|
|
</tr>
|
|
</table>
|
|
|
|
<p><b>Notes:</b></p>
|
|
|
|
<div class="doc_notes">
|
|
<ol>
|
|
<li><a name="pf_1">Code generation supported for Pentium processors and
|
|
up</a></li>
|
|
<li><a name="pf_2">Code generation supported for 32-bit ABI only</a></li>
|
|
<li><a name="pf_3">No native code generation</a></li>
|
|
<li><a name="pf_4">Build is not complete: one or more tools don't link</a></li>
|
|
<li><a name="pf_5">The GCC-based C/C++ frontend does not build</a></li>
|
|
<li><a name="pf_6">The port is done using the MSYS shell.
|
|
<a href="http://www.mingw.org/MinGWiki/">Download</a> and install
|
|
bison (excl. M4.exe) and flex in that order. Build binutils-2.15 from source,
|
|
if necessary.</li>
|
|
<li><a name="pf_7">Native code generation exists but is not complete.</a></li>
|
|
</ol>
|
|
</div>
|
|
|
|
<p>Note that you will need about 1-3 GB of space for a full LLVM build in Debug
|
|
mode, depending on the system (it is so large because of all the debugging
|
|
information and the fact that the libraries are statically linked into multiple
|
|
tools). If you do not need many of the tools and you are space-conscious,
|
|
you can disable them individually in <tt>llvm/tools/Makefile</tt>. The Release
|
|
build requires considerably less space.</p>
|
|
|
|
<p>The LLVM suite <i>may</i> compile on other platforms, but it is not
|
|
guaranteed to do so. If compilation is successful, the LLVM utilities should be
|
|
able to assemble, disassemble, analyze, and optimize LLVM bytecode. Code
|
|
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="CFEBuildInstrs.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">
|
|
<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
|
|
column provides "known to work" versions of the package. The Notes column
|
|
describes how LLVM uses the package and provides other details.</p>
|
|
<table>
|
|
<tr><th>Package</th><th>Version</th><th>Notes</th></tr>
|
|
|
|
<tr>
|
|
<td><a href="http://savannah.gnu.org/projects/make">GNU Make</a></td>
|
|
<td>3.79, 3.79.1</td>
|
|
<td>Makefile/build processor</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<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>4.5</td>
|
|
<td>For building the CFE</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td><a href="http://www.gnu.org/software/flex">Flex</a></td>
|
|
<td>2.5.4</td>
|
|
<td>LEX compiler</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td><a href="http://www.gnu.org/software/bison/bison.html">Bison</a></td>
|
|
<td>1.28, 1.35, 1.75, 1.875d, 2.0, or 2.1<br>(not 1.85 or 1.875)</td>
|
|
<td>YACC compiler</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td><a href="https://www.cvshome.org/downloads.html">CVS</a></td>
|
|
<td>≥1.11</td>
|
|
<td>CVS access to LLVM<sup><a href="#sf2">2</a></sup></td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td><a href="http://savannah.gnu.org/projects/dejagnu">DejaGnu</a></td>
|
|
<td>1.4.2</td>
|
|
<td>Automated test suite<sup><a href="#sf3">3</a></sup></td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td><a href="http://www.tcl.tk/software/tcltk/">tcl</a></td>
|
|
<td>8.3, 8.4</td>
|
|
<td>Automated test suite<sup><a href="#sf3">3</a></sup></td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td><a href="http://expect.nist.gov/">expect</a></td>
|
|
<td>5.38.0</td>
|
|
<td>Automated test suite<sup><a href="#sf3">3</a></sup></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>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td><a href="http://savannah.gnu.org/projects/m4">GNU M4</a>
|
|
<td>1.4</td>
|
|
<td>Macro processor for configuration<sup><a href="#sf4">4</a></sup></td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td><a href="http://www.gnu.org/software/autoconf">GNU Autoconf</a></td>
|
|
<td>2.59</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>1.9.2</td>
|
|
<td>aclocal macro generator<sup><a href="#sf4">4</a></sup></td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td><a href="http://savannah.gnu.org/projects/libtool">libtool</a></td>
|
|
<td>1.5.10</td>
|
|
<td>Shared library manager<sup><a href="#sf4">4</a></sup></td>
|
|
</tr>
|
|
|
|
</table>
|
|
|
|
<p><b>Notes:</b></p>
|
|
<div class="doc_notes">
|
|
<ol>
|
|
<li><a name="sf3">Only the C and C++ languages are needed so there's no
|
|
need to build the other languages for LLVM's purposes.</a> See
|
|
<a href="#brokengcc">below</a> for specific version info.</li>
|
|
<li><a name="sf2">You only need CVS if you intend to build from the
|
|
latest LLVM sources. If you're working from a release distribution, you
|
|
don't need CVS.</a></li>
|
|
<li><a name="sf3">Only needed if you want to run the automated test
|
|
suite in the <tt>llvm/test</tt> directory.</a></li>
|
|
<li><a name="sf4">If you want to make changes to the configure scripts,
|
|
you will need GNU autoconf (2.59), and consequently, GNU M4 (version 1.4
|
|
or higher). You will also need automake (1.9.2). We only use aclocal
|
|
from that package.</a></li>
|
|
</ol>
|
|
</div>
|
|
|
|
<p>Additionally, your compilation host is expected to have the usual
|
|
plethora of Unix utilities. Specifically:</p>
|
|
<ul>
|
|
<li><b>ar</b> - archive library builder</li>
|
|
<li><b>bzip2*</b> - bzip2 command for distribution generation</li>
|
|
<li><b>bunzip2*</b> - bunzip2 command for distribution checking</li>
|
|
<li><b>chmod</b> - change permissions on a file</li>
|
|
<li><b>cat</b> - output concatenation utility</li>
|
|
<li><b>cp</b> - copy files</li>
|
|
<li><b>date</b> - print the current date/time </li>
|
|
<li><b>echo</b> - print to standard output</li>
|
|
<li><b>egrep</b> - extended regular expression search utility</li>
|
|
<li><b>etags</b> - C/C++ tag file creator for vim/emacs</li>
|
|
<li><b>find</b> - find files/dirs in a file system</li>
|
|
<li><b>grep</b> - regular expression search utility</li>
|
|
<li><b>gzip*</b> - gzip command for distribution generation</li>
|
|
<li><b>gunzip*</b> - gunzip command for distribution checking</li>
|
|
<li><b>install</b> - install directories/files </li>
|
|
<li><b>mkdir</b> - create a directory</li>
|
|
<li><b>mv</b> - move (rename) files</li>
|
|
<li><b>ranlib</b> - symbol table builder for archive libraries</li>
|
|
<li><b>rm</b> - remove (delete) files and directories</li>
|
|
<li><b>sed</b> - stream editor for transforming output</li>
|
|
<li><b>sh</b> - Bourne shell for make build scripts</li>
|
|
<li><b>tar</b> - tape archive for distribution generation</li>
|
|
<li><b>test</b> - test things in file system</li>
|
|
<li><b>unzip*</b> - unzip command for distribution checking</li>
|
|
<li><b>zip*</b> - zip command for distribution generation</li>
|
|
</ul>
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection">
|
|
<a name="brokengcc">Broken versions of GCC</a>
|
|
</div>
|
|
|
|
<div class="doc_text">
|
|
|
|
<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 and GCC 3.4.0 and have had success
|
|
with them (however, see below). 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
|
|
us know</a>. Please use the "<tt>gcc -v</tt>" command to find out which version
|
|
of GCC you are using.
|
|
</p>
|
|
|
|
<p><b>GCC versions prior to 3.0</b>: GCC 2.96.x and before had several
|
|
problems in the STL that effectively prevent it from compiling LLVM.
|
|
</p>
|
|
|
|
<p><b>GCC 3.2.2</b>: This version of GCC fails to compile LLVM.</p>
|
|
|
|
<p><b>GCC 3.3.2</b>: This version of GCC suffered from a <a
|
|
href="http://gcc.gnu.org/PR13392">serious bug</a> which causes it to crash in
|
|
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="CFEBuildInstrs.html#cygwin">upgrade
|
|
to a newer version</a> if possible.</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
|
|
to a newer version of GCC.</p>
|
|
<p><b>IA-64 GCC 4.0.0</b>: The IA-64 version of GCC 4.0.0 is known to
|
|
miscompile LLVM.</p>
|
|
</div>
|
|
|
|
|
|
|
|
<!-- *********************************************************************** -->
|
|
<div class="doc_section">
|
|
<a name="starting"><b>Getting Started with LLVM</b></a>
|
|
</div>
|
|
<!-- *********************************************************************** -->
|
|
|
|
<div class="doc_text">
|
|
|
|
<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>
|
|
|
|
<p>The later sections of this guide describe the <a
|
|
href="#layout">general layout</a> of the the LLVM source tree, a <a
|
|
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">
|
|
<a name="terminology">Terminology and Notation</a>
|
|
</div>
|
|
|
|
<div class="doc_text">
|
|
|
|
<p>Throughout this manual, the following names are used to denote paths
|
|
specific to the local system and working environment. <i>These are not
|
|
environment variables you need to set but just strings used in the rest
|
|
of this document below</i>. In any of the examples below, simply replace
|
|
each of these names with the appropriate pathname on your local system.
|
|
All these paths are absolute:</p>
|
|
|
|
<dl>
|
|
<dt>SRC_ROOT
|
|
<dd>
|
|
This is the top level directory of the LLVM source tree.
|
|
<p>
|
|
|
|
<dt>OBJ_ROOT
|
|
<dd>
|
|
This is the top level directory of the LLVM object tree (i.e. the
|
|
tree where object files and compiled programs will be placed. It
|
|
can be the same as SRC_ROOT).
|
|
<p>
|
|
|
|
<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>cfrontend/<i>platform</i>/llvm-gcc</tt>.
|
|
</dl>
|
|
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection">
|
|
<a name="environment">Setting Up Your Environment</a>
|
|
</div>
|
|
|
|
<div class="doc_text">
|
|
|
|
<p>
|
|
In order to compile and use LLVM, you may need to set some environment
|
|
variables.
|
|
|
|
<dl>
|
|
<dt><tt>LLVM_LIB_SEARCH_PATH</tt>=<tt>/path/to/your/bytecode/libs</tt></dt>
|
|
<dd>[Optional] This environment variable helps LLVM linking tools find the
|
|
locations of your bytecode libraries. It is provided only as a
|
|
convenience since you can specify the paths using the -L options of the
|
|
tools and the C/C++ front-end will automatically use the bytecode files
|
|
installed in its
|
|
<tt>lib</tt> directory.</dd>
|
|
</dl>
|
|
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection">
|
|
<a name="unpack">Unpacking the LLVM Archives</a>
|
|
</div>
|
|
|
|
<div class="doc_text">
|
|
|
|
<p>
|
|
If you have the LLVM distribution, you will need to unpack it before you
|
|
can begin to compile it. LLVM is distributed as a set of two files: the LLVM
|
|
suite and the LLVM GCC front end compiled for your platform. There is an
|
|
additional test suite that is optional. Each file is a TAR archive that is
|
|
compressed with the gzip program.
|
|
</p>
|
|
|
|
<p>The files are as follows, with <em>x.y</em> marking the version number:
|
|
<dl>
|
|
<dt><tt>llvm-x.y.tar.gz</tt></dt>
|
|
<dd>Source release for the LLVM libraries and tools.<br/></dd>
|
|
|
|
<dt><tt>llvm-test-x.y.tar.gz</tt></dt>
|
|
<dd>Source release for the LLVM test suite.</dd>
|
|
|
|
<dt><tt>cfrontend-x.y.source.tar.gz</tt></dt>
|
|
<dd>Source release of the GCC front end.<br/></dd>
|
|
|
|
<dt><tt>cfrontend-x.y.i686-redhat-linux-gnu.tar.gz</tt></dt>
|
|
<dd>Binary release of the GCC front end for Linux/x86.<br/></dd>
|
|
|
|
<dt><tt>llvm-gcc4-x.y.source.tar.gz</tt></dt>
|
|
<dd>Source release of the llvm-gcc4 front end. See README.LLVM in the root
|
|
directory for build instructions.<br/></dd>
|
|
|
|
<dt><tt>llvm-gcc4-x.y.powerpc-apple-darwin8.6.0.tar.gz</tt></dt>
|
|
<dd>Binary release of the llvm-gcc4 front end for MacOS X/PowerPC.<br/></dd>
|
|
|
|
<dt><tt>llvm-gcc4-x.y.i686-apple-darwin8.6.1.tar.gz</tt></dt>
|
|
<dd>Binary release of the llvm-gcc4 front end for MacOS X/X86.<br/></dd>
|
|
</dl>
|
|
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection">
|
|
<a name="checkout">Checkout LLVM from CVS</a>
|
|
</div>
|
|
|
|
<div class="doc_text">
|
|
|
|
<p>If you have access to our CVS repository, you can get a fresh copy of
|
|
the entire source code. All you need to do is check it out from CVS as
|
|
follows:</p>
|
|
|
|
<ul>
|
|
<li><tt>cd <i>where-you-want-llvm-to-live</i></tt>
|
|
<li><tt>cvs -d :pserver:anon@llvm-cvs.cs.uiuc.edu:/var/cvs/llvm login</tt>
|
|
<li>Hit the return key when prompted for the password.
|
|
<li><tt>cvs -z3 -d :pserver:anon@llvm-cvs.cs.uiuc.edu:/var/cvs/llvm co
|
|
llvm</tt>
|
|
</ul>
|
|
|
|
<p>This will create an '<tt>llvm</tt>' directory in the current
|
|
directory and fully populate it with the LLVM source code, Makefiles,
|
|
test directories, and local copies of documentation files.</p>
|
|
|
|
<p>If you want to get a specific release (as opposed to the most recent
|
|
revision), you can specify a label. The following releases have the following
|
|
labels:</p>
|
|
|
|
<ul>
|
|
<li>Release 1.7: <b>RELEASE_17</b></li>
|
|
<li>Release 1.6: <b>RELEASE_16</b></li>
|
|
<li>Release 1.5: <b>RELEASE_15</b></li>
|
|
<li>Release 1.4: <b>RELEASE_14</b></li>
|
|
<li>Release 1.3: <b>RELEASE_13</b></li>
|
|
<li>Release 1.2: <b>RELEASE_12</b></li>
|
|
<li>Release 1.1: <b>RELEASE_11</b></li>
|
|
<li>Release 1.0: <b>RELEASE_1</b></li>
|
|
</ul>
|
|
|
|
<p>If you would like to get the LLVM test suite (a separate package as of 1.4),
|
|
you get it from the CVS repository:</p>
|
|
<pre>
|
|
cd llvm/projects
|
|
cvs -z3 -d :pserver:anon@llvm-cvs.cs.uiuc.edu:/var/cvs/llvm co llvm-test
|
|
</pre>
|
|
<p>By placing it in the <tt>llvm/projects</tt>, it will be automatically
|
|
configured by the LLVM configure script as well as automatically updated when
|
|
you run <tt>cvs update</tt>.</p>
|
|
|
|
<p>If you would like to get the GCC 3.4 front end source code, you can also get it from the CVS repository:</p>
|
|
|
|
<pre>
|
|
cvs -z3 -d :pserver:anon@llvm-cvs.cs.uiuc.edu:/var/cvs/llvm co llvm-gcc
|
|
</pre>
|
|
|
|
<p>Please note that you must follow <a href="CFEBuildInstrs.html">these
|
|
instructions</a> to successfully build the LLVM GCC front-end.</p>
|
|
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection">
|
|
<a name="installcf">Install the GCC Front End</a>
|
|
</div>
|
|
|
|
<div class="doc_text">
|
|
|
|
<p>Before configuring and compiling the LLVM suite, you need to extract the LLVM
|
|
GCC front end from the binary distribution. It is used for building the
|
|
bytecode libraries later used by the GCC front end for linking programs, and its
|
|
location must be specified when the LLVM suite is configured.</p>
|
|
|
|
<p>To install the GCC front end, do the following:</p>
|
|
|
|
<ol>
|
|
<li><tt>cd <i>where-you-want-the-front-end-to-live</i></tt></li>
|
|
<li><tt>gunzip --stdout cfrontend-<i>version</i>.<i>platform</i>.tar.gz | tar -xvf
|
|
-</tt></li>
|
|
</ol>
|
|
|
|
<p>Next, you will need to fix your system header files:</p>
|
|
|
|
<p><tt>cd cfrontend/<i>platform</i><br>
|
|
./fixheaders</tt></p>
|
|
|
|
<p>The binary versions of the 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.</p>
|
|
|
|
<p>In cases like these, you may want to try <a
|
|
href="CFEBuildInstrs.html">building the GCC front end from source.</a> This is
|
|
not for the faint of heart, so be forewarned.</p>
|
|
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection">
|
|
<a name="config">Local LLVM Configuration</a>
|
|
</div>
|
|
|
|
<div class="doc_text">
|
|
|
|
<p>Once checked out from the CVS repository, the LLVM suite source code must be
|
|
configured via the <tt>configure</tt> script. This script sets variables in the
|
|
various <tt>*.in</tt> files, most notably <tt>llvm/Makefile.config</tt> and
|
|
<tt>llvm/include/Config/config.h</tt>. It also populates <i>OBJ_ROOT</i> with
|
|
the Makefiles needed to begin building LLVM.</p>
|
|
|
|
<p>The following environment variables are used by the <tt>configure</tt>
|
|
script to configure the build system:</p>
|
|
|
|
<table>
|
|
<tr><th>Variable</th><th>Purpose</th></tr>
|
|
<tr>
|
|
<td>CC</td>
|
|
<td>Tells <tt>configure</tt> which C compiler to use. By default,
|
|
<tt>configure</tt> will look for the first GCC C compiler in
|
|
<tt>PATH</tt>. Use this variable to override
|
|
<tt>configure</tt>'s default behavior.</td>
|
|
</tr>
|
|
<tr>
|
|
<td>CXX</td>
|
|
<td>Tells <tt>configure</tt> which C++ compiler to use. By default,
|
|
<tt>configure</tt> will look for the first GCC C++ compiler in
|
|
<tt>PATH</tt>. Use this variable to override
|
|
<tt>configure</tt>'s default behavior.</td>
|
|
</tr>
|
|
</table>
|
|
|
|
<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="CFEBuildInstrs.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.
|
|
<p></p>
|
|
</dd>
|
|
<dt><i>--enable-optimized</i></dt>
|
|
<dd>
|
|
Enables optimized compilation by default (debugging symbols are removed
|
|
and GCC optimization flags are enabled). The default is to use an
|
|
unoptimized build (also known as a debug build).
|
|
<p></p>
|
|
</dd>
|
|
<dt><i>--enable-debug-runtime</i></dt>
|
|
<dd>
|
|
Enables debug symbols in the runtime libraries. The default is to strip
|
|
debug symbols from the runtime libraries.
|
|
</dd>
|
|
<dt><i>--enable-jit</i></dt>
|
|
<dd>
|
|
Compile the Just In Time (JIT) compiler functionality. This is not
|
|
available
|
|
on all platforms. The default is dependent on platform, so it is best
|
|
to explicitly enable it if you want it.
|
|
<p></p>
|
|
</dd>
|
|
<dt><i>--enable-targets=</i><tt>target-option</tt></dt>
|
|
<dd>Controls which targets will be built and linked into llc. The default
|
|
value for <tt>target_options</tt> is "all" which builds and links all
|
|
available targets. The value "host-only" can be specified to build only a
|
|
native compiler (no cross-compiler targets available). The "native" target is
|
|
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>.
|
|
<p></p></dd>
|
|
<dt><i>--enable-doxygen</i></dt>
|
|
<dd>Look for the doxygen program and enable construction of doxygen based
|
|
documentation from the source code. This is disabled by default because
|
|
generating the documentation can take a long time and producess 100s of
|
|
megabytes of output.</dd>
|
|
</dl>
|
|
|
|
<p>To configure LLVM, follow these steps:</p>
|
|
|
|
<ol>
|
|
<li>Change directory into the object root directory:
|
|
<br>
|
|
<tt>cd <i>OBJ_ROOT</i></tt>
|
|
<p>
|
|
|
|
<li>Run the <tt>configure</tt> script located in the LLVM source tree:
|
|
<br>
|
|
<tt><i>SRC_ROOT</i>/configure --prefix=/install/path [other options]</tt>
|
|
<p>
|
|
</ol>
|
|
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection">
|
|
<a name="compile">Compiling the LLVM Suite Source Code</a>
|
|
</div>
|
|
|
|
<div class="doc_text">
|
|
|
|
<p>Once you have configured LLVM, you can build it. There are three types of
|
|
builds:</p>
|
|
|
|
<dl>
|
|
<dt>Debug Builds
|
|
<dd>
|
|
These builds are the default when one types <tt>gmake</tt> (unless the
|
|
<tt>--enable-optimized</tt> option was used during configuration). The
|
|
build system will compile the tools and libraries with debugging
|
|
information.
|
|
<p>
|
|
|
|
<dt>Release (Optimized) Builds
|
|
<dd>
|
|
These builds are enabled with the <tt>--enable-optimized</tt> option to
|
|
<tt>configure</tt> or by specifying <tt>ENABLE_OPTIMIZED=1</tt> on the
|
|
<tt>gmake</tt> command line. For these builds, the build system will
|
|
compile the tools and libraries with GCC optimizations enabled and strip
|
|
debugging information from the libraries and executables it generates.
|
|
<p>
|
|
|
|
<dt>Profile Builds
|
|
<dd>
|
|
These builds are for use with profiling. They compile profiling
|
|
information into the code for use with programs like <tt>gprof</tt>.
|
|
Profile builds must be started by specifying <tt>ENABLE_PROFILING=1</tt>
|
|
on the <tt>gmake</tt> command line.
|
|
</dl>
|
|
|
|
<p>Once you have LLVM configured, you can build it by entering the
|
|
<i>OBJ_ROOT</i> directory and issuing the following command:</p>
|
|
|
|
<p><tt>gmake</tt></p>
|
|
|
|
<p>If the build fails, please <a href="#brokengcc">check here</a> to see if you
|
|
are using a version of GCC that is known not to compile LLVM.</p>
|
|
|
|
<p>
|
|
If you have multiple processors in your machine, you may wish to use some of
|
|
the parallel build options provided by GNU Make. For example, you could use the
|
|
command:</p>
|
|
|
|
<p><tt>gmake -j2</tt></p>
|
|
|
|
<p>There are several special targets which are useful when working with the LLVM
|
|
source code:</p>
|
|
|
|
<dl>
|
|
<dt><tt>gmake clean</tt>
|
|
<dd>
|
|
Removes all files generated by the build. This includes object files,
|
|
generated C/C++ files, libraries, and executables.
|
|
<p>
|
|
|
|
<dt><tt>gmake dist-clean</tt>
|
|
<dd>
|
|
Removes everything that <tt>gmake clean</tt> does, but also removes files
|
|
generated by <tt>configure</tt>. It attempts to return the source tree to the
|
|
original state in which it was shipped.
|
|
<p>
|
|
|
|
<dt><tt>gmake install</tt>
|
|
<dd>
|
|
Installs LLVM header files, libraries, tools, and documentation in a
|
|
hierarchy
|
|
under $PREFIX, specified with <tt>./configure --prefix=[dir]</tt>, which
|
|
defaults to <tt>/usr/local</tt>.
|
|
<p>
|
|
|
|
<dt><tt>gmake -C runtime install-bytecode</tt>
|
|
<dd>
|
|
Assuming you built LLVM into $OBJDIR, when this command is run, it will
|
|
install bytecode libraries into the GCC front end's bytecode library
|
|
directory. If you need to update your bytecode libraries,
|
|
this is the target to use once you've built them.
|
|
<p>
|
|
</dl>
|
|
|
|
<p>Please see the <a href="MakefileGuide.html">Makefile Guide</a> for further
|
|
details on these <tt>make</tt> targets and descriptions of other targets
|
|
available.</p>
|
|
|
|
<p>It is also possible to override default values from <tt>configure</tt> by
|
|
declaring variables on the command line. The following are some examples:</p>
|
|
|
|
<dl>
|
|
<dt><tt>gmake ENABLE_OPTIMIZED=1</tt>
|
|
<dd>
|
|
Perform a Release (Optimized) build.
|
|
<p>
|
|
|
|
<dt><tt>gmake ENABLE_OPTIMIZED=1 DISABLE_ASSERTIONS=1</tt>
|
|
<dd>
|
|
Perform a Release (Optimized) build without assertions enabled.
|
|
<p>
|
|
|
|
<dt><tt>gmake ENABLE_PROFILING=1</tt>
|
|
<dd>
|
|
Perform a Profiling build.
|
|
<p>
|
|
|
|
<dt><tt>gmake VERBOSE=1</tt>
|
|
<dd>
|
|
Print what <tt>gmake</tt> is doing on standard output.
|
|
<p>
|
|
|
|
<dt><tt>gmake TOOL_VERBOSE=1</tt></dt>
|
|
<dd>Ask each tool invoked by the makefiles to print out what it is doing on
|
|
the standard output. This also implies <tt>VERBOSE=1</tt>.
|
|
<p></dd>
|
|
</dl>
|
|
|
|
<p>Every directory in the LLVM object tree includes a <tt>Makefile</tt> to build
|
|
it and any subdirectories that it contains. Entering any directory inside the
|
|
LLVM object tree and typing <tt>gmake</tt> should rebuild anything in or below
|
|
that directory that is out of date.</p>
|
|
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection">
|
|
<a name="objfiles">The Location of LLVM Object Files</a>
|
|
</div>
|
|
|
|
<div class="doc_text">
|
|
|
|
<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
|
|
platforms or configurations using the same source tree.</p>
|
|
|
|
<p>This is accomplished in the typical autoconf manner:</p>
|
|
|
|
<ul>
|
|
<li><p>Change directory to where the LLVM object files should live:</p>
|
|
|
|
<p><tt>cd <i>OBJ_ROOT</i></tt></p></li>
|
|
|
|
<li><p>Run the <tt>configure</tt> script found in the LLVM source
|
|
directory:</p>
|
|
|
|
<p><tt><i>SRC_ROOT</i>/configure</tt></p></li>
|
|
</ul>
|
|
|
|
<p>The LLVM build will place files underneath <i>OBJ_ROOT</i> in directories
|
|
named after the build type:</p>
|
|
|
|
<dl>
|
|
<dt>Debug Builds
|
|
<dd>
|
|
<dl>
|
|
<dt>Tools
|
|
<dd><tt><i>OBJ_ROOT</i>/Debug/bin</tt>
|
|
<dt>Libraries
|
|
<dd><tt><i>OBJ_ROOT</i>/Debug/lib</tt>
|
|
</dl>
|
|
<p>
|
|
|
|
<dt>Release Builds
|
|
<dd>
|
|
<dl>
|
|
<dt>Tools
|
|
<dd><tt><i>OBJ_ROOT</i>/Release/bin</tt>
|
|
<dt>Libraries
|
|
<dd><tt><i>OBJ_ROOT</i>/Release/lib</tt>
|
|
</dl>
|
|
<p>
|
|
|
|
<dt>Profile Builds
|
|
<dd>
|
|
<dl>
|
|
<dt>Tools
|
|
<dd><tt><i>OBJ_ROOT</i>/Profile/bin</tt>
|
|
<dt>Libraries
|
|
<dd><tt><i>OBJ_ROOT</i>/Profile/lib</tt>
|
|
</dl>
|
|
</dl>
|
|
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection">
|
|
<a name="optionalconfig">Optional Configuration Items</a>
|
|
</div>
|
|
|
|
<div class="doc_text">
|
|
|
|
<p>
|
|
If you're running on a Linux system that supports the "<a
|
|
href="http://www.tat.physik.uni-tuebingen.de/~rguenth/linux/binfmt_misc.html">
|
|
binfmt_misc</a>"
|
|
module, and you have root access on the system, you can set your system up to
|
|
execute LLVM bytecode files directly. To do this, use commands like this (the
|
|
first command may not be required if you are already using the module):</p>
|
|
|
|
<div class="doc_code">
|
|
<pre>
|
|
$ mount -t binfmt_misc none /proc/sys/fs/binfmt_misc
|
|
$ echo ':llvm:M::llvm::/path/to/lli:' > /proc/sys/fs/binfmt_misc/register
|
|
$ chmod u+x hello.bc (if needed)
|
|
$ ./hello.bc
|
|
</pre>
|
|
</div>
|
|
|
|
<p>
|
|
This allows you to execute LLVM bytecode files directly. Thanks to Jack
|
|
Cummings for pointing this out!
|
|
</p>
|
|
|
|
</div>
|
|
|
|
|
|
<!-- *********************************************************************** -->
|
|
<div class="doc_section">
|
|
<a name="layout"><b>Program Layout</b></a>
|
|
</div>
|
|
<!-- *********************************************************************** -->
|
|
|
|
<div class="doc_text">
|
|
|
|
<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://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="cvsdir"><tt>CVS</tt> directories</a></div>
|
|
<div class="doc_text">
|
|
<p>Every directory checked out of CVS will contain a <tt>CVS</tt> directory; for
|
|
the most part these can just be ignored.</p>
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection"><a name="examples"><tt>llvm/examples</tt></a></div>
|
|
<div class="doc_text">
|
|
<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">
|
|
|
|
<p>This directory contains public header files exported from the LLVM
|
|
library. The three main subdirectories of this directory are:</p>
|
|
|
|
<dl>
|
|
<dt><tt><b>llvm/include/llvm</b></tt></dt>
|
|
<dd>This directory contains all of the LLVM specific header files. This
|
|
directory also has subdirectories for different portions of LLVM:
|
|
<tt>Analysis</tt>, <tt>CodeGen</tt>, <tt>Target</tt>, <tt>Transforms</tt>,
|
|
etc...</dd>
|
|
|
|
<dt><tt><b>llvm/include/llvm/Support</b></tt></dt>
|
|
<dd>This directory contains generic support libraries that are provided with
|
|
LLVM but not necessarily specific to LLVM. For example, some C++ STL utilities
|
|
and a Command Line option processing library store their header files here.
|
|
</dd>
|
|
|
|
<dt><tt><b>llvm/include/llvm/Config</b></tt></dt>
|
|
<dd>This directory contains header files configured by the <tt>configure</tt>
|
|
script. They wrap "standard" UNIX and C header files. Source code can
|
|
include these header files which automatically take care of the conditional
|
|
#includes that the <tt>configure</tt> script generates.</dd>
|
|
</dl>
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection"><a name="lib"><tt>llvm/lib</tt></a></div>
|
|
<div class="doc_text">
|
|
|
|
<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
|
|
different <a href="#tools">tools</a>.</p>
|
|
|
|
<dl>
|
|
<dt><tt><b>llvm/lib/VMCore/</b></tt></dt>
|
|
<dd> This directory holds the core LLVM source files that implement core
|
|
classes like Instruction and BasicBlock.</dd>
|
|
|
|
<dt><tt><b>llvm/lib/AsmParser/</b></tt></dt>
|
|
<dd>This directory holds the source code for the LLVM assembly language parser
|
|
library.</dd>
|
|
|
|
<dt><tt><b>llvm/lib/ByteCode/</b></tt></dt>
|
|
<dd>This directory holds code for reading and write LLVM bytecode.</dd>
|
|
|
|
<dt><tt><b>llvm/lib/Analysis/</b></tt><dd>This directory contains a variety of
|
|
different program analyses, such as Dominator Information, Call Graphs,
|
|
Induction Variables, Interval Identification, Natural Loop Identification,
|
|
etc.</dd>
|
|
|
|
<dt><tt><b>llvm/lib/Transforms/</b></tt></dt>
|
|
<dd> This directory contains the source code for the LLVM to LLVM program
|
|
transformations, such as Aggressive Dead Code Elimination, Sparse Conditional
|
|
Constant Propagation, Inlining, Loop Invariant Code Motion, Dead Global
|
|
Elimination, and many others.</dd>
|
|
|
|
<dt><tt><b>llvm/lib/Target/</b></tt></dt>
|
|
<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>
|
|
|
|
<dt><tt><b>llvm/lib/CodeGen/</b></tt></dt>
|
|
<dd> This directory contains the major parts of the code generator: Instruction
|
|
Selector, Instruction Scheduling, and Register Allocation.</dd>
|
|
|
|
<dt><tt><b>llvm/lib/Debugger/</b></tt></dt>
|
|
<dd> This directory contains the source level debugger library that makes
|
|
it possible to instrument LLVM programs so that a debugger could identify
|
|
source code locations at which the program is executing.</dd>
|
|
|
|
<dt><tt><b>llvm/lib/ExecutionEngine/</b></tt></dt>
|
|
<dd> This directory contains libraries for executing LLVM bytecode directly
|
|
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>
|
|
|
|
<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>
|
|
</dl>
|
|
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection"><a name="projects"><tt>llvm/projects</tt></a></div>
|
|
<div class="doc_text">
|
|
<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
|
|
to set up your own project. See <tt>llvm/projects/Stacker</tt> for a fully
|
|
functional example of a compiler front end.</p>
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection"><a name="runtime"><tt>llvm/runtime</tt></a></div>
|
|
<div class="doc_text">
|
|
|
|
<p>This directory contains libraries which are compiled into LLVM bytecode and
|
|
used when linking programs with the GCC front end. Most of these libraries are
|
|
skeleton versions of real libraries; for example, libc is a stripped down
|
|
version of glibc.</p>
|
|
|
|
<p>Unlike the rest of the LLVM suite, this directory needs the LLVM GCC front
|
|
end to compile.</p>
|
|
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection"><a name="test"><tt>llvm/test</tt></a></div>
|
|
<div class="doc_text">
|
|
<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="llvmtest"><tt>llvm-test</tt></a></div>
|
|
<div class="doc_text">
|
|
<p>This is not a directory in the normal llvm module; it is a separate CVS
|
|
module that must be checked out (usually to <tt>projects/llvm-test</tt>). This
|
|
module contains a comprehensive correctness, performance, and benchmarking
|
|
test
|
|
suite for LLVM. It is a separate CVS module because not every LLVM user is
|
|
interested in downloading or building such a comprehensive test suite. For
|
|
further details on this test suite, please see the
|
|
<a href="TestingGuide.html">Testing Guide</a> document.</p>
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection"><a name="tools"><tt>llvm/tools</tt></a></div>
|
|
<div class="doc_text">
|
|
|
|
<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
|
|
always get help for a tool by typing <tt>tool_name --help</tt>. The
|
|
following is a brief introduction to the most important tools. More detailed
|
|
information is in the <a href="CommandGuide/index.html">Command Guide</a>.</p>
|
|
|
|
<dl>
|
|
<dt><tt><b>analyze</b></tt></dt>
|
|
<dd><tt>analyze</tt> is used to run a specific
|
|
analysis on an input LLVM bytecode file and print out the results. It is
|
|
primarily useful for debugging analyses, or familiarizing yourself with
|
|
what an analysis does.</dd>
|
|
|
|
<dt><tt><b>bugpoint</b></tt></dt>
|
|
<dd><tt>bugpoint</tt> is used to debug
|
|
optimization passes or code generation backends by narrowing down the
|
|
given test case to the minimum number of passes and/or instructions that
|
|
still cause a problem, whether it is a crash or miscompilation. See <a
|
|
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 bytecode. 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 bytecode files, optionally with an index for faster
|
|
lookup.</dd>
|
|
|
|
<dt><tt><b>llvm-as</b></tt></dt>
|
|
<dd>The assembler transforms the human readable LLVM assembly to LLVM
|
|
bytecode.</dd>
|
|
|
|
<dt><tt><b>llvm-dis</b></tt></dt>
|
|
<dd>The disassembler transforms the LLVM bytecode to human readable
|
|
LLVM assembly.</dd>
|
|
|
|
<dt><tt><b>llvm-ld</b></tt></dt>
|
|
<dd><tt>llvm-ld</tt> is very similar to gccld and provides a general purpose
|
|
and extensible linker for LLVM. This is the linker invoked by <tt>llvmc</tt>.
|
|
It allows optimization modules to be loaded so that language specific
|
|
optimizations can be applied at link time. This tool is considered
|
|
experimental.</dd>
|
|
|
|
<dt><tt><b>llvm-link</b></tt></dt>
|
|
<dd><tt>llvm-link</tt>, not surprisingly, links multiple LLVM modules into
|
|
a single program.</dd>
|
|
|
|
<dt><tt><b>lli</b></tt></dt>
|
|
<dd><tt>lli</tt> is the LLVM interpreter, which
|
|
can directly execute LLVM bytecode (although very slowly...). In addition
|
|
to a simple interpreter, <tt>lli</tt> also has a tracing mode (entered by
|
|
specifying <tt>-trace</tt> on the command line). Finally, for
|
|
architectures that support it (currently x86, Sparc, and PowerPC), by default,
|
|
<tt>lli</tt> will function as a Just-In-Time compiler (if the
|
|
functionality was compiled in), and will execute the code <i>much</i>
|
|
faster than the interpreter.</dd>
|
|
|
|
<dt><tt><b>llc</b></tt></dt>
|
|
<dd> <tt>llc</tt> is the LLVM backend compiler, which
|
|
translates LLVM bytecode to a native code assembly file or to C code (with
|
|
the -march=c option).</dd>
|
|
|
|
<dt><tt><b>llvm-gcc</b></tt></dt>
|
|
<dd><tt>llvm-gcc</tt> is a GCC-based C frontend
|
|
that has been retargeted to emit LLVM code as the machine code output. It
|
|
works just like any other GCC compiler, taking the typical <tt>-c, -S, -E,
|
|
-o</tt> options that are typically used. The source code for the
|
|
<tt>llvm-gcc</tt> tool is available as a separate CVS module.
|
|
<blockquote>
|
|
<dl>
|
|
<dt><tt><b>gccas</b></tt></dt>
|
|
<dd>This tool is invoked by the <tt>llvm-gcc</tt> frontend as the
|
|
"assembler" part of the compiler. This tool actually assembles LLVM
|
|
assembly to LLVM bytecode, performs a variety of optimizations, and
|
|
outputs LLVM bytecode. Thus when you invoke
|
|
<tt>llvm-gcc -c x.c -o x.o</tt>, you are causing <tt>gccas</tt> to be
|
|
run, which writes the <tt>x.o</tt> file (which is an LLVM bytecode file
|
|
that can be disassembled or manipulated just like any other bytecode
|
|
file). The command line interface to <tt>gccas</tt> is designed to be
|
|
as close as possible to the <b>system</b> `<tt>as</tt>' utility so that
|
|
the gcc frontend itself did not have to be modified to interface to
|
|
a "weird" assembler.</dd>
|
|
|
|
<dt><tt><b>gccld</b></tt></dt>
|
|
<dd><tt>gccld</tt> links together several LLVM bytecode files into one
|
|
bytecode file and does some optimization. It is the linker invoked by
|
|
the GCC frontend when multiple .o files need to be linked together.
|
|
Like <tt>gccas</tt>, the command line interface of <tt>gccld</tt> is
|
|
designed to match the system linker, to aid interfacing with the GCC
|
|
frontend.</dd>
|
|
</dl>
|
|
</blockquote>
|
|
</dd>
|
|
|
|
<dt><tt><b>opt</b></tt></dt>
|
|
<dd><tt>opt</tt> reads LLVM bytecode, applies a
|
|
series of LLVM to LLVM transformations (which are specified on the command
|
|
line), and then outputs the resultant bytecode. The '<tt>opt --help</tt>'
|
|
command is a good way to get a list of the program transformations
|
|
available in LLVM.</dd>
|
|
</dl>
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection"><a name="utils"><tt>llvm/utils</tt></a></div>
|
|
<div class="doc_text">
|
|
|
|
<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
|
|
are code generators for parts of LLVM infrastructure.</p>
|
|
|
|
<dl>
|
|
<dt><tt><b>codegen-diff</b></tt> <dd><tt>codegen-diff</tt> is a script
|
|
that finds differences between code that LLC generates and code that LLI
|
|
generates. This is a useful tool if you are debugging one of them,
|
|
assuming that the other generates correct output. For the full user
|
|
manual, run <tt>`perldoc codegen-diff'</tt>.<p>
|
|
|
|
<dt><tt><b>cvsupdate</b></tt> <dd><tt>cvsupdate</tt> is a script that will
|
|
update your CVS tree, but produce a much cleaner and more organized output
|
|
than simply running <tt>`cvs -z3 up -dP'</tt> will. For example, it will group
|
|
together all the new and updated files and modified files in separate
|
|
sections, so you can see at a glance what has changed. If you are at the
|
|
top of your LLVM CVS tree, running <tt>utils/cvsupdate</tt> is the
|
|
preferred way of updating the tree.<p>
|
|
|
|
<dt><tt><b>emacs/</b></tt> <dd>The <tt>emacs</tt> directory contains
|
|
syntax-highlighting files which will work with Emacs and XEmacs editors,
|
|
providing syntax highlighting support for LLVM assembly files and TableGen
|
|
description files. For information on how to use the syntax files, consult
|
|
the <tt>README</tt> file in that directory.<p>
|
|
|
|
<dt><tt><b>getsrcs.sh</b></tt> <dd>The <tt>getsrcs.sh</tt> script finds
|
|
and outputs all non-generated source files, which is useful if one wishes
|
|
to do a lot of development across directories and does not want to
|
|
individually find each file. One way to use it is to run, for example:
|
|
<tt>xemacs `utils/getsources.sh`</tt> from the top of your LLVM source
|
|
tree.<p>
|
|
|
|
<dt><tt><b>llvmgrep</b></tt></dt>
|
|
<dd>This little tool performs an "egrep -H -n" on each source file in LLVM and
|
|
passes to it a regular expression provided on <tt>llvmgrep</tt>'s command
|
|
line. This is a very efficient way of searching the source base for a
|
|
particular regular expression.</dd>
|
|
|
|
<dt><tt><b>makellvm</b></tt> <dd>The <tt>makellvm</tt> script compiles all
|
|
files in the current directory and then compiles and links the tool that
|
|
is the first argument. For example, assuming you are in the directory
|
|
<tt>llvm/lib/Target/Sparc</tt>, if <tt>makellvm</tt> is in your path,
|
|
simply running <tt>makellvm llc</tt> will make a build of the current
|
|
directory, switch to directory <tt>llvm/tools/llc</tt> and build it,
|
|
causing a re-linking of LLC.<p>
|
|
|
|
<dt><tt><b>NightlyTest.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>.<p>
|
|
|
|
<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
|
|
files.<p>
|
|
|
|
<dt><tt><b>vim/</b></tt> <dd>The <tt>vim</tt> directory contains
|
|
syntax-highlighting files which will work with the VIM editor, providing
|
|
syntax highlighting support for LLVM assembly files and TableGen
|
|
description files. For information on how to use the syntax files, consult
|
|
the <tt>README</tt> file in that directory.<p>
|
|
|
|
</dl>
|
|
|
|
</div>
|
|
|
|
<!-- ======================================================================= -->
|
|
<div class="doc_subsection"><a name="win32"><tt>llvm/win32</tt></a></div>
|
|
<div class="doc_text">
|
|
<p>This directory contains build scripts and project files for use with
|
|
Visual C++. This allows developers on Windows to build LLVM without the need
|
|
for Cygwin. The contents of this directory should be considered experimental
|
|
at this time.
|
|
</p>
|
|
</div>
|
|
<!-- *********************************************************************** -->
|
|
<div class="doc_section">
|
|
<a name="tutorial">An Example Using the LLVM Tool Chain</a>
|
|
</div>
|
|
<!-- *********************************************************************** -->
|
|
|
|
<div class="doc_text">
|
|
|
|
<ol>
|
|
<li>First, create a simple C file, name it 'hello.c':
|
|
<pre>
|
|
#include <stdio.h>
|
|
int main() {
|
|
printf("hello world\n");
|
|
return 0;
|
|
}
|
|
</pre></li>
|
|
|
|
<li><p>Next, compile the C file into a LLVM bytecode file:</p>
|
|
<p><tt>% llvm-gcc hello.c -o hello</tt></p>
|
|
|
|
<p>Note that you should have already built the tools and they have to be
|
|
in your path, at least <tt>gccas</tt> and <tt>gccld</tt>.</p>
|
|
|
|
<p>This will create two result files: <tt>hello</tt> and
|
|
<tt>hello.bc</tt>. The <tt>hello.bc</tt> is the LLVM bytecode that
|
|
corresponds the the compiled program and the library facilities that it
|
|
required. <tt>hello</tt> is a simple shell script that runs the bytecode
|
|
file with <tt>lli</tt>, making the result directly executable. Note that
|
|
all LLVM optimizations are enabled by default, so there is no need for a
|
|
"-O3" switch.</p></li>
|
|
|
|
<li><p>Run the program. To make sure the program ran, execute one of the
|
|
following commands:</p>
|
|
|
|
<p><tt>% ./hello</tt></p>
|
|
|
|
<p>or</p>
|
|
|
|
<p><tt>% lli hello.bc</tt></p></li>
|
|
|
|
<li><p>Use the <tt>llvm-dis</tt> utility to take a look at the LLVM assembly
|
|
code:</p>
|
|
|
|
<p><tt>% llvm-dis < hello.bc | less</tt><p></li>
|
|
|
|
<li><p>Compile the program to native assembly using the LLC code
|
|
generator:</p>
|
|
|
|
<p><tt>% llc hello.bc -o hello.s</tt></p>
|
|
|
|
<li><p>Assemble the native assembly language file into a program:</p>
|
|
|
|
<p><b>Solaris:</b><tt>% /opt/SUNWspro/bin/cc -xarch=v9 hello.s -o hello.native</tt></p>
|
|
<p><b>Others:</b><tt>% gcc hello.s -o hello.native</tt></p>
|
|
|
|
<li><p>Execute the native code program:</p>
|
|
|
|
<p><tt>% ./hello.native</tt></p></li>
|
|
|
|
</ol>
|
|
|
|
</div>
|
|
|
|
<!-- *********************************************************************** -->
|
|
<div class="doc_section">
|
|
<a name="problems">Common Problems</a>
|
|
</div>
|
|
<!-- *********************************************************************** -->
|
|
|
|
<div class="doc_text">
|
|
|
|
<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
|
|
Asked Questions</a> page.</p>
|
|
|
|
</div>
|
|
|
|
<!-- *********************************************************************** -->
|
|
<div class="doc_section">
|
|
<a name="links">Links</a>
|
|
</div>
|
|
<!-- *********************************************************************** -->
|
|
|
|
<div class="doc_text">
|
|
|
|
<p>This document is just an <b>introduction</b> to how to use LLVM to do
|
|
some simple things... there are many more interesting and complicated things
|
|
that you can do that aren't documented here (but we'll gladly accept a patch
|
|
if you want to write something up!). For more information about LLVM, check
|
|
out:</p>
|
|
|
|
<ul>
|
|
<li><a href="http://llvm.org/">LLVM homepage</a></li>
|
|
<li><a href="http://llvm.org/doxygen/">LLVM doxygen tree</a></li>
|
|
<li><a href="http://llvm.org/docs/Projects.html">Starting a Project
|
|
that Uses LLVM</a></li>
|
|
</ul>
|
|
|
|
</div>
|
|
|
|
<!-- *********************************************************************** -->
|
|
|
|
<hr>
|
|
<address>
|
|
<a href="http://jigsaw.w3.org/css-validator/check/referer"><img
|
|
src="http://jigsaw.w3.org/css-validator/images/vcss" alt="Valid CSS!"></a>
|
|
<a href="http://validator.w3.org/check/referer"><img
|
|
src="http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01!" /></a>
|
|
|
|
<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>
|
|
Last modified: $Date$
|
|
</address>
|
|
</body>
|
|
</html>
|