mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-12-26 21:32:10 +00:00
This is the initial draft of the Compiler Driver documentation. It is not
worthy of review at this point. There is much thought and content remaining to be written. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15574 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Reid Spencer
parent
524a60587d
commit
b1254a1247
572
docs/CompilerDriver.html
Normal file
572
docs/CompilerDriver.html
Normal file
@ -0,0 +1,572 @@
|
||||
<!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>The LLVM Compiler Driver (llvmc)</title>
|
||||
<link rel="stylesheet" href="llvm.css" type="text/css">
|
||||
<style type="text/css">
|
||||
TR, TD { border: 2px solid gray; padding: 4pt 4pt 2pt 2pt; }
|
||||
TH { border: 2px solid gray; font-weight: bold; font-size: 105%; }
|
||||
TABLE { text-align: center; border: 2px solid black;
|
||||
border-collapse: collapse; margin-top: 1em; margin-left: 1em;
|
||||
margin-right: 1em; margin-bottom: 1em; }
|
||||
.td_left { border: 2px solid gray; text-align: left; }
|
||||
</style>
|
||||
<meta name="author" content="Reid Spencer" name="author">
|
||||
<meta name="description"
|
||||
content="A description of the use and design of the LLVM Compiler Driver.">
|
||||
</head>
|
||||
<body>
|
||||
<div class="doc_title">The LLVM Compiler Driver (llvmc)</div>
|
||||
<p class="doc_warning">NOTE: This document is a work in progress!</p>
|
||||
<ol>
|
||||
<li><a href="#abstract">Abstract</a></li>
|
||||
<li><a href="#introduction">Introduction</a>
|
||||
<ol>
|
||||
<li><a href="#purpose">Purpose</a></li>
|
||||
<li><a href="#operation">Operation</a></li>
|
||||
<li><a href="#phases">Phases</a></li>
|
||||
<li><a href="#actions">Actions</a></li>
|
||||
</ol>
|
||||
</li>
|
||||
<li><a href="#details">Details</a>
|
||||
<li><a href="#configuration">Configuration</a>
|
||||
<li><a href="#glossary">Glossary</a>
|
||||
</ol>
|
||||
<div class="doc_author">
|
||||
<p>Written by <a href="mailto:rspencer@x10sys.com">Reid Spencer</a>
|
||||
</p>
|
||||
</div>
|
||||
|
||||
<!-- *********************************************************************** -->
|
||||
<div class="doc_section"> <a name="abstract">Abstract</a></div>
|
||||
<!-- *********************************************************************** -->
|
||||
<div class="doc_text">
|
||||
<p>This document describes the requirements, design, and configuration of the
|
||||
LLVM compiler driver, <tt>llvmc</tt>. The compiler driver knows about LLVM's
|
||||
tool set and can be configured to know about a variety of compilers for
|
||||
source languages. It uses this knowledge to execute the tools necessary
|
||||
to accomplish general compilation, optimization, and linking tasks. The main
|
||||
purpose of <tt>llvmc</tt> is to provide a simple and consistent interface to
|
||||
all compilation tasks. This reduces the burden on the end user who can just
|
||||
learn to use <tt>llvmc</tt> instead of the entire LLVM tool set and all the
|
||||
source language compilers compatible with LLVM.</p>
|
||||
</div>
|
||||
<!-- *********************************************************************** -->
|
||||
<div class="doc_section"> <a name="introduction">Introduction</a></div>
|
||||
<!-- *********************************************************************** -->
|
||||
<div class="doc_text">
|
||||
<p>The <tt>llvmc</tt> <a href="def_tool">tool</a> is a configurable compiler
|
||||
<a href="def_driver">driver</a>. As such, it isn't the compiler, optimizer,
|
||||
or linker itself but it drives (invokes) other software that perform those
|
||||
tasks. If you are familiar with the GNU Compiler Collection's <tt>gcc</tt>
|
||||
tool, <tt>llvmc</tt> is very similar.</p>
|
||||
<p>The following introductory sections will help you understand why this tool
|
||||
is necessary and what it does.</p>
|
||||
</div>
|
||||
|
||||
<!-- _______________________________________________________________________ -->
|
||||
<div class="doc_subsection"><a name="purpose">Purpose</a></div>
|
||||
<div class="doc_text">
|
||||
<p><tt>llvmc</tt> was invented to make compilation with LLVM based compilers
|
||||
easier. To accomplish this, <tt>llvmc</tt> strives to:</p>
|
||||
<ul>
|
||||
<li>Be the single point of access to most of the LLVM tool set.</li>
|
||||
<li>Hide the complexities of the LLVM tools through a single interface.</li>
|
||||
<li>Provide a consistent interface for compiling all languages.</li>
|
||||
</ul>
|
||||
<p>Additionally, <tt>llvmc</tt> makes it easier to write a compiler for use
|
||||
with LLVM, because it:</p>
|
||||
<ul>
|
||||
<li>Makes integration of existing non-LLVM tools simple.</li>
|
||||
<li>Extends the capabilities of minimal front ends by optimizing their
|
||||
output.</li>
|
||||
<li>Reduces the number of interfaces a compiler writer must know about
|
||||
before a working compiler can be completed (essentially only the VMCore
|
||||
interfaces need to be understood).</li>
|
||||
<li>Supports source language translator invocation via both dynamically
|
||||
loadable shared objects and invocation of an executable.</li>
|
||||
</ol>
|
||||
</p>
|
||||
</div>
|
||||
|
||||
<!-- _______________________________________________________________________ -->
|
||||
<div class="doc_subsection"><a name="operation">Operation</a></div>
|
||||
<div class="doc_text">
|
||||
<p>At a high level, <tt>llvmc</tt> operation is very simple. The basic action
|
||||
taken by <tt>llvmc</tt> is to simply invoke some tool or set of tools to fill
|
||||
the user's request for compilation. Every execution of <tt>llvmc</tt>takes the
|
||||
following sequence of steps:<br/>
|
||||
<dl>
|
||||
<dt><b>Collect Command Line Options</b></dt>
|
||||
<dd>The command line options provide the marching orders to <tt>llvmc</tt>
|
||||
on what actions it should perform. This is the request the user is making
|
||||
of <tt>llvmc</tt> and it is interpreted first. See the <tt>llvmc</tt>
|
||||
<a href="CommandGuide/html/llvmc.html">manual page</a> for details on the
|
||||
options.</dd>
|
||||
<dt><b>Read Configuration Files</b></dt>
|
||||
<dd>Based on the options and the suffixes of the filenames presented, a set
|
||||
of configuration files are read to configure the actions <tt>llvmc</tt> will
|
||||
take. Configuration files are provided by either LLVM or the front end
|
||||
compiler tools that B<llvmc> invokes. These files determine what actions
|
||||
<tt>llvmc</tt> will take in response to the user's request. See the section
|
||||
on <a href="#configuration">configuration</a> for more details.</dd>
|
||||
<dt><b>Determine Phases To Execute</b></dt>
|
||||
<dd>Based on the command line options and configuration files,
|
||||
<tt>llvmc</tt> determines the compilation <a href="#phases">phases</a> that
|
||||
must be executed by the user's request. This is the primary work of
|
||||
<tt>llvmc</tt>.</dd>
|
||||
<dt><b>Determine Actions To Execute</b></dt>
|
||||
<dd>Each <a href="#phases">phase</a> to be executed can result in the
|
||||
invocation of one or more <a href="#actions">actions</a>. An action is
|
||||
either a whole program or a function in a dynamically linked shared library.
|
||||
In this step, <tt>llvmc</tt> determines the sequence of actions that must be
|
||||
executed. Actions will always be executed in a deterministic order.</dd>
|
||||
<dt><b>Execute Actions</b></dt>
|
||||
<dd>The <a href="#actions">actions</a> necessary to support the user's
|
||||
original request are executed sequentially and deterministically. All
|
||||
actions result in either the invocation of a whole program to perform the
|
||||
action or the loading of a dynamically linkable shared library and invocation
|
||||
of a standard interface function within that library.</dd>
|
||||
<dt><b>Termination</b></dt>
|
||||
<dd>If any action fails (returns a non-zero result code), <tt>llvmc</tt>
|
||||
also fails and returns the result code from the failing action. If
|
||||
everything succeeds, <tt>llvmc</tt> will return a zero result code.</dd>
|
||||
</dl></p>
|
||||
<p><tt>llvmc</tt>'s operation must be simple, regular and predictable.
|
||||
Developers need to be able to rely on it to take a consistent approach to
|
||||
compilation. For example, the invocation:</p>
|
||||
<tt><pre>
|
||||
llvmc -O2 x.c y.c z.c -o xyz</pre></tt>
|
||||
<p>must produce <i>exactly</i> the same results as:</p>
|
||||
<tt><pre>
|
||||
llvmc -O2 x.c
|
||||
llvmc -O2 y.c
|
||||
llvmc -O2 z.c
|
||||
llvmc -O2 x.o y.o z.o -o xyz</pre></tt>
|
||||
<p>To accomplish this, <tt>llvmc</tt> uses a very simple goal oriented
|
||||
procedure to do its work. The overall goal is to produce a functioning
|
||||
executable. To accomplish this, <tt>llvmc</tt> always attempts to execute a
|
||||
series of compilation <a href="#def_phase">phases</a> in the same sequence.
|
||||
However, the user's options to <tt>llvmc</tt> can cause the sequence of phases
|
||||
to start in the middle or finish early.</p>
|
||||
</div>
|
||||
|
||||
<!-- _______________________________________________________________________ -->
|
||||
<div class="doc_subsection"><a name="phases"></a>Phases </div>
|
||||
<div class="doc_text">
|
||||
<p><tt>llvmc</tt> breaks every compilation task into the following five
|
||||
distinct phases:</p>
|
||||
<dl><dt><b>Preprocessing</b></dt><dd>Not all languages support preprocessing;
|
||||
but for those that do, this phase can be invoked. This phase is for
|
||||
languages that provide combining, filtering, or otherwise altering with the
|
||||
source language input before the translator parses it. Although C and C++
|
||||
are the most common users of this phase, other languages may provide their
|
||||
own preprocessor (whether its the C pre-processor or not).</dd>
|
||||
</dl>
|
||||
<dl><dt><b>Translation</b></dt><dd>The translation phase converts the source
|
||||
language input into something that LLVM can interpret and use for
|
||||
downstream phases. The translation is essentially from "non-LLVM form" to
|
||||
"LLVM form".</dd>
|
||||
</dl>
|
||||
<dl><dt><b>Optimization</b></dt><dd>Once an LLVM Module has been obtained from
|
||||
the translation phase, the program enters the optimization phase. This phase
|
||||
attempts to optimize all of the input provided on the command line according
|
||||
to the options provided.</dd>
|
||||
</dl>
|
||||
<dl><dt><b>Linking</b></dt><dd>The inputs are combined to form a complete
|
||||
program.</dd>
|
||||
</dl>
|
||||
<p>The following table shows the inputs, outputs, and command line options
|
||||
applicabe to each phase.</p>
|
||||
<table>
|
||||
<tr>
|
||||
<th style="width: 10%">Phase</th>
|
||||
<th style="width: 25%">Inputs</th>
|
||||
<th style="width: 25%">Outputs</th>
|
||||
<th style="width: 40%">Options</th>
|
||||
</tr>
|
||||
<tr><td><b>Preprocessing</b></td>
|
||||
<td class="td_left"><ul><li>Source Language File</li></ul></td>
|
||||
<td class="td_left"><ul><li>Source Language File</li></ul></td>
|
||||
<td class="td_left"><dl>
|
||||
<dt><tt>-E</tt></dt>
|
||||
<dd>Stops the compilation after preprocessing</dd>
|
||||
</dl></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td><b>Translation</b></td>
|
||||
<td class="td_left"><ul>
|
||||
<li>Source Language File</li>
|
||||
</ul></td>
|
||||
<td class="td_left"><ul>
|
||||
<li>LLVM Assembly</li>
|
||||
<li>LLVM Bytecode</li>
|
||||
<li>LLVM C++ IR</li>
|
||||
</ul></td>
|
||||
<td class="td_left"><dl>
|
||||
<dt><tt>-c</tt></dt>
|
||||
<dd>Stops the compilation after translation so that optimization and
|
||||
linking are not done.</dd>
|
||||
<dt><tt>-S</tt></dt>
|
||||
<dd>Stops the compilation before object code is written so that only
|
||||
assembly code remains.</dd>
|
||||
</dl></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td><b>Optimization</b></td>
|
||||
<td class="td_left"><ul>
|
||||
<li>LLVM Assembly</li>
|
||||
<li>LLVM Bytecode</li>
|
||||
</ul></td>
|
||||
<td class="td_left"><ul>
|
||||
<li>LLVM Bytecode</li>
|
||||
</ul></td>
|
||||
<td class="td_left"><dl>
|
||||
<dt><tt>-Ox</tt>
|
||||
<dd>This group of options affects the amount of optimization
|
||||
performed.</dd>
|
||||
</dl></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td><b>Linking</b></td>
|
||||
<td class="td_left"><ul>
|
||||
<li>LLVM Bytecode</li>
|
||||
<li>Native Object Code</li>
|
||||
<li>LLVM Library</li>
|
||||
<li>Native Library</li>
|
||||
</ul></td>
|
||||
<td class="td_left"><ul>
|
||||
<li>LLVM Bytecode Executable</li>
|
||||
<li>Native Executable</li>
|
||||
</ul></td>
|
||||
<td class="td_left"><dl>
|
||||
<dt><tt>-L</tt></dt><dd>Specifies a path for library search.</dd>
|
||||
<dt><tt>-l</tt></dt><dd>Specifies a library to link in.</dd>
|
||||
</dl></td>
|
||||
</tr>
|
||||
</table>
|
||||
</div>
|
||||
|
||||
<!-- _______________________________________________________________________ -->
|
||||
<div class="doc_subsection"><a name="actions"></a>Actions</div>
|
||||
<div class="doc_text">
|
||||
<p>An action, with regard to <tt>llvmc</tt> is a basic operation that it takes
|
||||
in order to fulfill the user's request. Each phase of compilation will invoke
|
||||
zero or more actions in order to accomplish that phase.</p>
|
||||
<p>Actions come in two forms:<ol>
|
||||
<li>Invokable Executables</li>
|
||||
<li>Functions in a shared library</li>
|
||||
</ul></p>
|
||||
</div>
|
||||
|
||||
<!-- *********************************************************************** -->
|
||||
<div class="doc_section"><a name="details">Details</a></div>
|
||||
<!-- *********************************************************************** -->
|
||||
<div class="doc_text">
|
||||
</div>
|
||||
|
||||
<!-- *********************************************************************** -->
|
||||
<div class="doc_section"><a name="configuration">Configuration</a></div>
|
||||
<!-- *********************************************************************** -->
|
||||
<div class="doc_text">
|
||||
<p>This section of the document describes the configuration files used by
|
||||
<tt>llvmc</tt>. Configuration information is relatively static for a
|
||||
given release of LLVM and a front end compiler. However, the details may
|
||||
change from release to release of either. Users are encouraged to simply use
|
||||
the various options of the B<llvmc> command and ignore the configuration of
|
||||
the tool. These configuration files are for compiler writers and LLVM
|
||||
developers. Those wishing to simply use B<llvmc> don't need to understand
|
||||
this section but it may be instructive on how the tool works.</p>
|
||||
</div>
|
||||
|
||||
<!-- _______________________________________________________________________ -->
|
||||
<div class="doc_subsection"><a name="overview"></a>Overview</div>
|
||||
<div class="doc_text">
|
||||
<p><tt>llvmc</tt> is highly configurable both on the command line and in
|
||||
configuration files. The options it understands are generic, consistent and
|
||||
simple by design. Furthermore, the <tt>llvmc</tt> options apply to the
|
||||
compilation of any LLVM enabled programming language. To be enabled as a
|
||||
supported source language compiler, a compiler writer must provide a
|
||||
configuration file that tells <tt>llvmc</tt> how to invoke the compiler
|
||||
and what its capabilities are. The purpose of the configuration files then
|
||||
is to allow compiler writers to specify to <tt>llvmc</tt> how the compiler
|
||||
should be invoked. Users may but are not advised to alter the compiler's
|
||||
<tt>llvmc</tt> configuration.</p>
|
||||
|
||||
<p>Because <tt>llvmc</tt> just invokes other programs, it must deal with the
|
||||
available command line options for those programs regardless of whether they
|
||||
were written for LLVM or not. Furthermore, not all compilation front ends will
|
||||
have the same capabilities. Some front ends will simply generate LLVM assembly
|
||||
code, others will be able to generate fully optimized byte code. In general,
|
||||
<tt>llvmc</tt> doesn't make any assumptions about the capabilities or command
|
||||
line options of a sub-tool. It simply uses the details found in the configuration
|
||||
files and leaves it to the compiler writer to specify the configuration
|
||||
correctly.</p>
|
||||
|
||||
<p>This approach means that new compiler front ends can be up and working very
|
||||
quickly. As a first cut, a front end can simply compile its source to raw
|
||||
(unoptimized) bytecode or LLVM assembly and <tt>llvmc</tt> can be configured
|
||||
to pick up the slack (translate LLVM assembly to bytecode, optimize the
|
||||
bytecode, generate native assembly, link, etc.). In fact, the front end need
|
||||
not use any LLVM libraries, and it could be written in any language (instead of
|
||||
C++). The configuration data will allow the full range of optimization,
|
||||
assembly, and linking capabilities that LLVM provides to be added to these kinds
|
||||
of tools. Enabling the rapid development of front-ends is one of the primary
|
||||
goals of <tt>llvmc</tt>.</p>
|
||||
|
||||
<p>As a compiler front end matures, it may utilize the LLVM libraries and tools
|
||||
to more efficiently produce optimized bytecode directly in a single compilation
|
||||
and optimization program. In these cases, multiple tools would not be needed
|
||||
and the configuration data for the compiler would change.</p>
|
||||
|
||||
<p>Configuring <tt>llvmc</tt> to the needs and capabilities of a source language
|
||||
compiler is relatively straight forward. A compiler writer must provide a
|
||||
definition of what to do for each of the five compilation phases for each of
|
||||
the optimization levels. The specification consists simply of prototypical
|
||||
command lines into which <tt>llvmc</tt> can substitute command line
|
||||
arguments and file names. Note that any given phase can be completely blank if
|
||||
the source language's compiler combines multiple phases into a single program.
|
||||
For example, quite often pre-processing, translation, and optimization are
|
||||
combined into a single program. The specification for such a compiler would have
|
||||
blank entries for pre-processing and translation but a full command line for
|
||||
optimization.</p>
|
||||
</div>
|
||||
|
||||
<!-- _______________________________________________________________________ -->
|
||||
<div class="doc_subsection"><a name="filetypes"></a>Configuration Files</div>
|
||||
<div class="doc_text">
|
||||
<h3>Types of Files</h3>
|
||||
<p>There are two types of configuration files: the master configuration file
|
||||
and the language specific configuration file. The master configuration file
|
||||
contains the general configuration of <tt>llvmc</tt> itself and is supplied
|
||||
with the tool. It contains information that is source language agnostic.
|
||||
Language specific configuration files tell <tt>llvmc</tt> how to invoke the
|
||||
language's compiler for a variety of different tasks and what other tools
|
||||
are needed to backfill the compiler's missing features (e.g.
|
||||
optimization).</p>
|
||||
|
||||
<h3>Directory Search</h3>
|
||||
<p><tt>llvmc</tt> always looks for files of a specific name. It uses the
|
||||
first file with the name its looking for by searching directories in the
|
||||
following order:<br/>
|
||||
<ol>
|
||||
<li>Any directory specified by the <tt>--config-dir</tt> option will be
|
||||
checked first.</li>
|
||||
<li>If the environment variable LLVM_CONFIG_DIR is set, and it contains
|
||||
the name of a valid directory, that directory will be searched next.</li>
|
||||
<li>If the user's home directory (typically <tt>/home/user</tt> contains
|
||||
a sub-directory named <tt>.llvm</tt> and that directory contains a
|
||||
sub-directory named <tt>etc</tt> then that directory will be tried
|
||||
next.</li>
|
||||
<li>If the LLVM installation directory (typically <tt>/usr/local/llvm</tt>
|
||||
contains a sub-directory named <tt>etc</tt> then that directory will be
|
||||
tried last.</li>
|
||||
<li>If the configuration file sought still can't be found, <tt>llvmc</tt>
|
||||
will print an error message and exit.</li>
|
||||
</ol>
|
||||
The first file found in this search will be used. Other files with the same
|
||||
name will be ignored even if they exist in one of the subsequent search
|
||||
locations.</p>
|
||||
|
||||
<h3>File Names</h3>
|
||||
<p>In the directories searched, a file named <tt>master</tt> will be
|
||||
recognized as the master configuration file for <tt>llvmc</tt>. Note that
|
||||
users <i>may</i> override the master file with a copy in their home directory
|
||||
but they are advised not to. This capability is only useful for compiler
|
||||
implementers needing to alter the master configuration while developing
|
||||
their compiler front end. When reading the configuration files, the master
|
||||
files are always read first.</p>
|
||||
<p>Language specific configuration files are given specific names to foster
|
||||
faster lookup. The name of a given language specific configuration file is
|
||||
the same as the suffix used to identify files containing source in that
|
||||
language. For example, a configuration file for C++ source might be named
|
||||
<tt>cpp</tt>, <tt>C</tt>, or <tt>cxx</tt>.</p>
|
||||
|
||||
<h3>What Gets Read</h3>
|
||||
<p>The master configuration file is always read. Which language specific
|
||||
configuration files are read depends on the command line options and the
|
||||
suffixes of the file names provided on <tt>llvmc</tt>'s command line. Note
|
||||
that the <tt>--x LANGUAGE</tt> option alters the language that <tt>llvmc</tt>
|
||||
uses for the subsequent files on the command line. Only the language
|
||||
specific configuration files actually needed to complete <tt>llvmc</tt>'s
|
||||
task are read. Other language specific files will be ignored.</p>
|
||||
</div>
|
||||
|
||||
<!-- _______________________________________________________________________ -->
|
||||
<div class="doc_subsection"><a name="syntax"></a>Syntax</div>
|
||||
<div class="doc_text">
|
||||
<p>The syntax of the configuration files is yet to be determined. There are
|
||||
two viable options remaining:<br/>
|
||||
<ul>
|
||||
<li>XML DTD Specific To <tt>llvmc</tt></li>
|
||||
<li>Windows .ini style file with numerous sections</li>
|
||||
</ul></p>
|
||||
</div>
|
||||
|
||||
<!-- _______________________________________________________________________ -->
|
||||
<div class="doc_subsection"><a name="master_items"></a>
|
||||
Master Configuration Items
|
||||
</div>
|
||||
<div class="doc_text">
|
||||
<pre>
|
||||
|
||||
=head3 Section: [lang=I<LANGUAGE>]
|
||||
|
||||
This section provides the master configuration data for a given language. The
|
||||
language specific data will be found in a file named I<LANGUAGE>.
|
||||
|
||||
=over
|
||||
|
||||
=item C<suffix=>I<suffix>
|
||||
|
||||
This adds the I<suffix> specified to the list of recognized suffixes for
|
||||
the I<LANGUAGE> identified in the section. As many suffixes as are commonly used
|
||||
for source files for the I<LANGUAGE> should be specified.
|
||||
|
||||
=back
|
||||
|
||||
=begin html
|
||||
|
||||
<p>For example, the following might appear for C++:
|
||||
<pre><tt>
|
||||
[lang=C++]
|
||||
suffix=.cpp
|
||||
suffix=.cxx
|
||||
suffix=.C
|
||||
</tt></pre></p>
|
||||
|
||||
=end html
|
||||
</pre>
|
||||
</div>
|
||||
|
||||
<!-- _______________________________________________________________________ -->
|
||||
<div class="doc_subsection"><a name="lang_items"></a>
|
||||
Language Specific Configuration Items
|
||||
</div>
|
||||
<div class="doc_text">
|
||||
<pre>
|
||||
=head3 Section: [general]
|
||||
|
||||
=over
|
||||
|
||||
=item C<hasPreProcessor=yes|no>
|
||||
|
||||
This item specifies whether the language has a pre-processing phase or not. This
|
||||
controls whether the B<-E> option works for the language or not.
|
||||
|
||||
=item C<output=bc|ll>
|
||||
|
||||
This item specifies the kind of output the language's compiler generates. The
|
||||
choices are either bytecode (C<bc>) or LLVM assembly (C<ll>).
|
||||
|
||||
=back
|
||||
|
||||
=head3 Section: [-O0]
|
||||
|
||||
=over
|
||||
|
||||
=item C<preprocess=>I<commandline>
|
||||
|
||||
This item specifies the I<commandline> to use for pre-processing the input.
|
||||
|
||||
=over
|
||||
|
||||
Valid substitutions for this item are:
|
||||
|
||||
=item %in%
|
||||
|
||||
The input source file.
|
||||
|
||||
=item %out%
|
||||
|
||||
The output file.
|
||||
|
||||
=item %options%
|
||||
|
||||
Any pre-processing specific options (e.g. B<-I>).
|
||||
|
||||
=back
|
||||
|
||||
=item C<translate=>I<commandline>
|
||||
|
||||
This item specifies the I<commandline> to use for translating the source
|
||||
language input into the output format given by the C<output> item.
|
||||
|
||||
=item C<optimize=>I<commandline>
|
||||
|
||||
This item specifies the I<commandline> for optimizing the translator's output.
|
||||
|
||||
=back
|
||||
</pre>
|
||||
</div>
|
||||
|
||||
<!-- *********************************************************************** -->
|
||||
<div class="doc_section"><a name="glossary">Glossary</a></div>
|
||||
<!-- *********************************************************************** -->
|
||||
<div class="doc_text">
|
||||
<p>This document uses precise terms in reference to the various artifacts and
|
||||
concepts related to compilation. The terms used throughout this document are
|
||||
defined below.</p>
|
||||
<dl>
|
||||
<dt><a name="def_assembly"><b>assembly</b></a></dt>
|
||||
<dd>A compilation <a href="#def_phase">phase</a> in which LLVM bytecode or
|
||||
LLVM assembly code is assembled to a native code format (either target
|
||||
specific aseembly language or the platform's native object file format).
|
||||
</dd>
|
||||
|
||||
<dt><a name="def_compiler"><b>compiler</b></a></dt>
|
||||
<dd>Refers to any program that can be invoked by <tt>llvmc</tt> to accomplish
|
||||
the work of one or more compilation <a href="#def_phase">phases</a>.</dd>
|
||||
|
||||
<dt><a name="def_driver"><b>driver</b></a></dt>
|
||||
<dd>Refers to <tt>llvmc</tt> itself.</dd>
|
||||
|
||||
<dt><a name="def_linking"><b>linking</b></a></dt>
|
||||
<dd>A compilation <a href="#def_phase">phase</a> in which LLVM bytecode files
|
||||
and (optionally) native system libraries are combined to form a complete
|
||||
executable program.</dd>
|
||||
|
||||
<dt><a name="def_optimization"><b>optimization</b></a></dt>
|
||||
<dd>A compilation <a href="#def_phase">phase</a> in which LLVM bytecode is
|
||||
optimized.</dd>
|
||||
|
||||
<dt><a name="def_phase"><b>phase</b></a></dt>
|
||||
<dd>Refers to any one of the five compilation phases that that
|
||||
<tt>llvmc</tt> supports. The five phases are:
|
||||
<a href="#def_preprocessing">preprocessing</a>,
|
||||
<a href="#def_translation">translation</a>,
|
||||
<a href="#def_optimization">optimization</a>,
|
||||
<a href="#def_assembly">assembly</a>,
|
||||
<a href="#def_linking">linking</a>.</dd>
|
||||
|
||||
<dt><a name="def_sourcelanguage"><b>source language</b></a></dt>
|
||||
<dd>Any common programming language (e.g. C, C++, Java, Stacker, ML,
|
||||
FORTRAN). These languages are distinguished from any of the lower level
|
||||
languages (such as LLVM or native assembly), by the fact that a
|
||||
<a href="#def_translation">translation</a> <a href="#def_phase">phase</a>
|
||||
is required before LLVM can be applied.</dd>
|
||||
|
||||
<dt><a name="def_tool"><b>tool</b></a></dt>
|
||||
<dd>Refers to any program in the LLVM tool set.</dd>
|
||||
|
||||
<dt><a name="def_translation"><b>translation</b></a></dt>
|
||||
<dd>A compilation <a href="#def_phase">phase</a> in which
|
||||
<a href="#def_sourcelanguage">source language</a> code is translated into
|
||||
either LLVM assembly language or LLVM bytecode.</dd>
|
||||
</dl>
|
||||
</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:rspencer@x10sys.com">Reid Spencer</a><br>
|
||||
<a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br>
|
||||
Last modified: $Date$
|
||||
</address>
|
||||
<!-- vim: sw=2
|
||||
-->
|
||||
</body>
|
||||
</html>
|
||||
Loading…
Reference in New Issue
Block a user