2011-11-04 01:55:59 +08:00
|
|
|
<!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>LLVMBuild Documentation</title>
|
|
|
|
<link rel="stylesheet" href="llvm.css" type="text/css">
|
|
|
|
</head>
|
|
|
|
<body>
|
|
|
|
|
|
|
|
<h1>LLVMBuild Guide</h1>
|
|
|
|
|
|
|
|
<ol>
|
|
|
|
<li><a href="#introduction">Introduction</a></li>
|
|
|
|
<li><a href="#projectorg">Project Organization</a></li>
|
|
|
|
<li><a href="#buildintegration">Build Integration</a></li>
|
|
|
|
<li><a href="#componentoverview">Component Overview</a></li>
|
|
|
|
<li><a href="#formatreference">Format Reference</a></li>
|
|
|
|
</ol>
|
|
|
|
|
|
|
|
<!-- *********************************************************************** -->
|
|
|
|
<h2><a name="introduction">Introduction</a></h2>
|
|
|
|
<!-- *********************************************************************** -->
|
|
|
|
|
|
|
|
<div>
|
|
|
|
<p>This document describes the <tt>LLVMBuild</tt> organization and files which
|
|
|
|
we use to describe parts of the LLVM ecosystem. For description of specific
|
|
|
|
LLVMBuild related tools, please see the command guide.</p>
|
|
|
|
|
|
|
|
<p>LLVM is designed to be a modular set of libraries which can be flexibly
|
|
|
|
mixed together in order to build a variety of tools, like compilers, JITs,
|
|
|
|
custom code generators, optimization passes, interpreters, and so on. Related
|
|
|
|
projects in the LLVM system like Clang and LLDB also tend to follow this
|
|
|
|
philosophy.</p>
|
|
|
|
|
|
|
|
<p>In order to support this usage style, LLVM has a fairly strict structure as
|
|
|
|
to how the source code and various components are organized. The
|
|
|
|
<tt>LLVMBuild.txt</tt> files are the explicit specification of that structure,
|
|
|
|
and are used by the build systems and other tools in order to develop the LLVM
|
|
|
|
project.</p>
|
|
|
|
</div>
|
|
|
|
|
|
|
|
<!-- *********************************************************************** -->
|
|
|
|
<h2><a name="projectorg">Project Organization</a></h2>
|
|
|
|
<!-- *********************************************************************** -->
|
|
|
|
|
|
|
|
<!-- FIXME: We should probably have an explicit top level project object. Good
|
|
|
|
place to hang project level data, name, etc. Also useful for serving as the
|
|
|
|
$ROOT of project trees for things which can be checked out separately. -->
|
|
|
|
|
|
|
|
<div>
|
|
|
|
<p>The source code for LLVM projects using the LLVMBuild system (LLVM, Clang,
|
|
|
|
and LLDB) is organized into <em>components</em>, which define the separate
|
|
|
|
pieces of functionality that make up the project. These projects may consist
|
|
|
|
of many libraries, associated tools, build tools, or other utility tools (for
|
|
|
|
example, testing tools).</p>
|
|
|
|
|
|
|
|
<p>For the most part, the project contents are organized around defining one
|
|
|
|
main component per each subdirectory. Each such directory contains
|
|
|
|
an <tt>LLVMBuild.txt</tt> which contains the component definitions.</p>
|
|
|
|
|
|
|
|
<p>The component descriptions for the project as a whole are automatically
|
|
|
|
gathered by the LLVMBuild tools. The tools automatically traverse the source
|
|
|
|
directory structure to find all of the component description files. NOTE: For
|
|
|
|
performance/sanity reasons, we only traverse into subdirectories when the
|
|
|
|
parent itself contains an <tt>LLVMBuild.txt</tt> description file.</p>
|
|
|
|
</div>
|
|
|
|
|
|
|
|
<!-- *********************************************************************** -->
|
|
|
|
<h2><a name="buildintegration">Build Integration</a></h2>
|
|
|
|
<!-- *********************************************************************** -->
|
|
|
|
|
|
|
|
<div>
|
|
|
|
<p>The LLVMBuild files themselves are just a declarative way to describe the
|
|
|
|
project structure. The actual building of the LLVM project is handled by
|
|
|
|
another build system (currently we support
|
|
|
|
both <a href="MakefileGuide.html">Makefiles</a>
|
|
|
|
and <a href="CMake.html">CMake</a>.</p>
|
|
|
|
|
|
|
|
<p>The build system implementation will load the relevant contents of the
|
|
|
|
LLVMBuild files and use that to drive the actual project build. Typically, the
|
|
|
|
build system will only need to load this information at "configure" time, and
|
|
|
|
use it to generative native information. Build systems will also handle
|
|
|
|
automatically reconfiguring their information when the contents of
|
|
|
|
the <i>LLVMBuild.txt</i> files change.</p>
|
|
|
|
|
|
|
|
<p>Developers generally are not expected to need to be aware of the details of
|
|
|
|
how the LLVMBuild system is integrated into their build. Ideally, LLVM
|
|
|
|
developers who are not working on the build system would only ever need to
|
|
|
|
modify the contents of the <i>LLVMBuild.txt</i> description files (although we
|
|
|
|
have not reached this goal yet).</p>
|
2011-11-04 01:56:24 +08:00
|
|
|
|
|
|
|
<p>For more information on the utility tool we provide to help interfacing
|
|
|
|
with the build system, please see
|
|
|
|
the <a href="CommandGuide/html/llvm-build.html">llvm-build</a>
|
|
|
|
documentation.</p>
|
2011-11-04 01:55:59 +08:00
|
|
|
</div>
|
|
|
|
|
|
|
|
<!-- *********************************************************************** -->
|
|
|
|
<h2><a name="componentoverview">Component Overview</a></h2>
|
|
|
|
<!-- *********************************************************************** -->
|
|
|
|
|
|
|
|
<div>
|
|
|
|
<p>As mentioned earlier, LLVM projects are organized into
|
|
|
|
logical <em>components</em>. Every component is typically grouped into it's
|
|
|
|
own subdirectory. Generally, a component is organized around a coherent group
|
|
|
|
of sources which have some kind of clear API separation from other parts of
|
|
|
|
the code.</p>
|
|
|
|
|
|
|
|
<p>LLVM primarily uses the following types of components:</p>
|
|
|
|
<ul>
|
|
|
|
<li><em>Libraries</em> - Library components define a distinct API which can
|
|
|
|
be independently linked into LLVM client applications. Libraries typically
|
|
|
|
have private and public header files, and may specify a link of required
|
|
|
|
libraries that they build on top of.</li>
|
|
|
|
|
|
|
|
<li><em>Build Tools</em> - Build tools are applications which are designed
|
|
|
|
to be run as part of the build process (typically to generate other source
|
|
|
|
files). Currently, LLVM uses one main build tool
|
|
|
|
called <a href="TableGenFundamentals.html">TableGen</a> to generate a
|
|
|
|
variety of source files.</li>
|
|
|
|
|
|
|
|
<li><em>Tools</em> - Command line applications which are built using the
|
|
|
|
LLVM component libraries. Most LLVM tools are small and are primarily
|
|
|
|
frontends to the library interfaces.</li>
|
|
|
|
|
|
|
|
<!-- FIXME: We also need shared libraries as a first class component, but this
|
|
|
|
is not yet implemented. -->
|
|
|
|
</ul>
|
|
|
|
|
|
|
|
<p>Components are described using <em>LLVMBuild.txt</em> files in the
|
|
|
|
directories that define the component. See
|
|
|
|
the <a href="#formatreference">Format Reference</a> section for information on
|
|
|
|
the exact format of these files.</p>
|
|
|
|
</div>
|
|
|
|
|
|
|
|
<!-- *********************************************************************** -->
|
2011-11-10 08:49:51 +08:00
|
|
|
<h2><a name="formatreference">LLVMBuild Format Reference</a></h2>
|
2011-11-04 01:55:59 +08:00
|
|
|
<!-- *********************************************************************** -->
|
|
|
|
|
|
|
|
<div>
|
|
|
|
<p>LLVMBuild files are written in a simple variant of the INI or configuration
|
|
|
|
file format (<a href="http://en.wikipedia.org/wiki/INI_file">Wikipedia
|
|
|
|
entry</a>). The format defines a list of sections each of which may contain
|
|
|
|
some number of properties. A simple example of the file format is below:</p>
|
|
|
|
<div class="doc_code">
|
|
|
|
<pre>
|
|
|
|
<i>; Comments start with a semi-colon.</i>
|
|
|
|
|
|
|
|
<i>; Sections are declared using square brackets.</i>
|
2011-12-13 06:45:59 +08:00
|
|
|
[component_0]
|
2011-11-04 01:55:59 +08:00
|
|
|
|
|
|
|
<i>; Properties are declared using '=' and are contained in the previous section.
|
|
|
|
;
|
2011-11-10 08:49:51 +08:00
|
|
|
; We support simple string and boolean scalar values and list values, where
|
|
|
|
; items are separated by spaces. There is no support for quoting, and so
|
|
|
|
; property values may not contain spaces.</i>
|
2011-11-04 01:55:59 +08:00
|
|
|
property_name = property_value
|
|
|
|
list_property_name = value_1 value_2 <em>...</em> value_n
|
2011-11-10 08:49:51 +08:00
|
|
|
boolean_property_name = 1 <em>(or 0)</em>
|
2011-11-04 01:55:59 +08:00
|
|
|
</pre>
|
|
|
|
</div>
|
|
|
|
|
2011-12-13 06:45:59 +08:00
|
|
|
<p>LLVMBuild files are expected to define a strict set of sections and
|
2011-11-04 01:55:59 +08:00
|
|
|
properties. An typical component description file for a library
|
|
|
|
component would look typically look like the following example:</p>
|
|
|
|
<div class="doc_code">
|
|
|
|
<pre>
|
|
|
|
[component_0]
|
|
|
|
type = Library
|
|
|
|
name = Linker
|
|
|
|
parent = Libraries
|
|
|
|
required_libraries = Archive BitReader Core Support TransformUtils
|
|
|
|
</pre>
|
|
|
|
</div class="doc_code">
|
|
|
|
|
|
|
|
<p>A full description of the exact sections and properties which are allowed
|
|
|
|
follows.</p>
|
|
|
|
|
2011-12-13 06:45:59 +08:00
|
|
|
<p>Each file may define exactly one common component, named "common". The
|
|
|
|
common component may define the following properties:</p>
|
|
|
|
<ul>
|
|
|
|
<li><i>subdirectories</i> <b>[optional]</b>
|
|
|
|
<p>If given, a list of the names of the subdirectories from the current
|
|
|
|
subpath to search for additional LLVMBuild files.</p></li>
|
|
|
|
</ul>
|
|
|
|
|
2011-11-04 01:55:59 +08:00
|
|
|
<p>Each file may define multiple components. Each component is described by a
|
|
|
|
section who name starts with "component". The remainder of the section name is
|
|
|
|
ignored, but each section name must be unique. Typically components are just
|
|
|
|
number in order for files with multiple components ("component_0",
|
|
|
|
"component_1", and so on).<p>
|
|
|
|
|
2011-12-13 06:45:59 +08:00
|
|
|
<p><b>Section names not matches this format (or the "common" section) are
|
|
|
|
currently unused and are disallowed.</b></p>
|
2011-11-04 01:55:59 +08:00
|
|
|
|
|
|
|
<p>Every component is defined by the properties in the section. The exact list
|
|
|
|
of properties that are allowed depends on the component
|
|
|
|
type. Components <b>may not</b> define any properties other than those
|
|
|
|
expected by the component type.</p>
|
|
|
|
|
|
|
|
<p>Every component must define the following properties:</p>
|
|
|
|
<ul>
|
|
|
|
<li><i>type</i> <b>[required]</b>
|
|
|
|
<p>The type of the component. Supported component types are
|
|
|
|
detailed below. Most components will define additional properties which
|
|
|
|
may be required or optional.</p></li>
|
|
|
|
|
|
|
|
<li><i>name</i> <b>[required]</b>
|
|
|
|
<p>The name of the component. Names are required to be unique
|
|
|
|
across the entire project.</p></li>
|
|
|
|
|
|
|
|
<li><i>parent</i> <b>[required]</b>
|
|
|
|
<p>The name of the logical parent of the component. Components are
|
|
|
|
organized into a logical tree to make it easier to navigate and organize
|
|
|
|
groups of components. The parent's have no semantics as far as the project
|
|
|
|
build is concerned, however. Typically, the parent will be the main
|
|
|
|
component of the parent directory.</p>
|
|
|
|
|
|
|
|
<!-- FIXME: Should we make the parent optional, and default to parent
|
|
|
|
directories component? -->
|
|
|
|
|
|
|
|
<p>Components may reference the root pseudo component using '$ROOT' to
|
|
|
|
indicate they should logically be grouped at the top-level.</p>
|
|
|
|
</li>
|
|
|
|
</ul>
|
|
|
|
|
|
|
|
<p>Components may define the following properties:</p>
|
|
|
|
<ul>
|
|
|
|
<li><i>dependencies</i> <b>[optional]</b>
|
|
|
|
<p>If specified, a list of names of components which <i>must</i> be built
|
|
|
|
prior to this one. This should only be exactly those components which
|
|
|
|
produce some tool or source code required for building the
|
|
|
|
component.</p>
|
|
|
|
|
|
|
|
<p><em>NOTE:</em> Group and LibraryGroup components have no semantics for
|
|
|
|
the actual build, and are not allowed to specify dependencies.</p></li>
|
|
|
|
</ul>
|
|
|
|
|
|
|
|
<p>The following section lists the available component types, as well as the
|
|
|
|
properties which are associated with that component.</p>
|
|
|
|
|
|
|
|
<ul>
|
|
|
|
<li><i>type = Group</i>
|
|
|
|
<p>Group components exist purely to allow additional arbitrary structuring
|
|
|
|
of the logical components tree. For example, one might define a
|
|
|
|
"Libraries" group to hold all of the root library components.</p>
|
|
|
|
|
|
|
|
<p>Group components have no additionally properties.</p>
|
|
|
|
</li>
|
|
|
|
|
|
|
|
<li><i>type = Library</i>
|
|
|
|
<p>Library components define an individual library which should be built
|
|
|
|
from the source code in the component directory.</p>
|
|
|
|
|
|
|
|
<p>Components with this type use the following properties:</p>
|
|
|
|
<ul>
|
|
|
|
<li><i>library_name</i> <b>[optional]</b>
|
|
|
|
<p>If given, the name to use for the actual library file on disk. If
|
|
|
|
not given, the name is derived from the component name
|
|
|
|
itself.</p></li>
|
|
|
|
|
|
|
|
<li><i>required_libraries</i> <b>[optional]</b>
|
|
|
|
<p>If given, a list of the names of Library or LibraryGroup components
|
|
|
|
which must also be linked in whenever this library is used. That is,
|
|
|
|
the link time dependencies for this component. When tools are built,
|
|
|
|
the build system will include the transitive closer of
|
|
|
|
all <i>required_libraries</i> for the components the tool needs.</p></li>
|
|
|
|
|
|
|
|
<li><i>add_to_library_groups</i> <b>[optional]</b>
|
|
|
|
<p>If given, a list of the names of LibraryGroup components which this
|
|
|
|
component is also part of. This allows nesting groups of
|
|
|
|
components. For example, the <i>X86</i> target might define a library
|
|
|
|
group for all of the <i>X86</i> components. That library group might
|
|
|
|
then be included in the <i>all-targets</i> library group.</p></li>
|
|
|
|
</ul>
|
|
|
|
</li>
|
|
|
|
|
|
|
|
<li><i>type = LibraryGroup</i>
|
|
|
|
<p>LibraryGroup components are a mechanism to allow easy definition of
|
|
|
|
useful sets of related components. In particular, we use them to easily
|
|
|
|
specify things like "all targets", or "all assembly printers".</p>
|
|
|
|
|
|
|
|
<p>Components with this type use the following properties:</p>
|
|
|
|
<ul>
|
|
|
|
<li><i>required_libraries</i> <b>[optional]</b>
|
|
|
|
<p>See the Library type for a description of this property.</p></li>
|
|
|
|
|
|
|
|
<li><i>add_to_library_groups</i> <b>[optional]</b>
|
|
|
|
<p>See the Library type for a description of this property.</p></li>
|
|
|
|
</ul>
|
|
|
|
</li>
|
|
|
|
|
2011-11-10 08:49:51 +08:00
|
|
|
<li><i>type = TargetGroup</i>
|
|
|
|
<p>TargetGroup components are an extension of LibraryGroups, specifically
|
|
|
|
for defining LLVM targets (which are handled specially in a few
|
|
|
|
places).</p>
|
|
|
|
|
|
|
|
<p>The name of the component should always be the name of the target.</p>
|
|
|
|
|
|
|
|
<p>Components with this type use the LibraryGroup properties in addition
|
|
|
|
to:</p>
|
|
|
|
<ul>
|
2011-11-11 08:23:56 +08:00
|
|
|
<li><i>has_asmparser</i> <b>[optional]</b> <b>[boolean]</b>
|
|
|
|
<p>Whether this target defines an assembly parser.</p></li>
|
|
|
|
<li><i>has_asmprinter</i> <b>[optional]</b> <b>[boolean]</b>
|
|
|
|
<p>Whether this target defines an assembly printer.</p></li>
|
|
|
|
<li><i>has_disassembler</i> <b>[optional]</b> <b>[boolean]</b>
|
|
|
|
<p>Whether this target defines a disassembler.</p></li>
|
2011-11-10 08:49:51 +08:00
|
|
|
<li><i>has_jit</i> <b>[optional]</b> <b>[boolean]</b>
|
|
|
|
<p>Whether this target supports JIT compilation.</p></li>
|
|
|
|
</ul>
|
|
|
|
</li>
|
|
|
|
|
2011-11-04 01:55:59 +08:00
|
|
|
<li><i>type = Tool</i>
|
|
|
|
<p>Tool components define standalone command line tools which should be
|
|
|
|
built from the source code in the component directory and linked.</p>
|
|
|
|
|
|
|
|
<p>Components with this type use the following properties:</p>
|
|
|
|
<ul>
|
|
|
|
<li><i>required_libraries</i> <b>[optional]</b>
|
|
|
|
|
|
|
|
<p>If given, a list of the names of Library or LibraryGroup components
|
|
|
|
which this tool is required to be linked with. <b>NOTE:</b> The values
|
|
|
|
should be the component names, which may not always match up with the
|
|
|
|
actual library names on disk.</p>
|
|
|
|
|
|
|
|
<p>Build systems are expected to properly include all of the libraries
|
|
|
|
required by the linked components (i.e., the transitive closer
|
|
|
|
of <em>required_libraries</em>).</p>
|
|
|
|
|
|
|
|
<p>Build systems are also expected to understand that those library
|
|
|
|
components must be built prior to linking -- they do not also need to
|
|
|
|
be listed under <i>dependencies</i>.</p></li>
|
|
|
|
</ul>
|
|
|
|
</li>
|
|
|
|
|
|
|
|
<li><i>type = BuildTool</i>
|
|
|
|
<p>BuildTool components are like Tool components, except that the tool is
|
|
|
|
supposed to be built for the platform where the build is running (instead
|
|
|
|
of that platform being targetted). Build systems are expected to handle
|
|
|
|
the fact that required libraries may need to be built for multiple
|
|
|
|
platforms in order to be able to link this tool.</p>
|
|
|
|
|
|
|
|
<p>BuildTool components currently use the exact same properties as Tool
|
|
|
|
components, the type distinction is only used to differentiate what the
|
|
|
|
tool is built for.</p>
|
|
|
|
</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-blue" alt="Valid CSS"></a>
|
|
|
|
<a href="http://validator.w3.org/check/referer"><img
|
|
|
|
src="http://www.w3.org/Icons/valid-html401-blue" alt="Valid HTML 4.01"></a>
|
|
|
|
|
|
|
|
<a href="http://llvm.org/">The LLVM Compiler Infrastructure</a><br>
|
|
|
|
Last modified: $Date$
|
|
|
|
</address>
|
|
|
|
</body>
|
|
|
|
</html>
|