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diff --git a/docs/CompilerDriverTutorial.html b/docs/CompilerDriverTutorial.html index 317b1d1..4ed373a 100644 --- a/docs/CompilerDriverTutorial.html +++ b/docs/CompilerDriverTutorial.html @@ -3,7 +3,7 @@ <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> -<meta name="generator" content="Docutils 0.5: http://docutils.sourceforge.net/" /> +<meta name="generator" content="Docutils 0.6: http://docutils.sourceforge.net/" /> <title>Tutorial - Using LLVMC</title> <link rel="stylesheet" href="llvm.css" type="text/css" /> </head> @@ -18,7 +18,7 @@ The ReST source lives in the directory 'tools/llvmc/doc'. --> <p class="topic-title first">Contents</p> <ul class="simple"> <li><a class="reference internal" href="#introduction" id="id1">Introduction</a></li> -<li><a class="reference internal" href="#compiling-with-llvmc" id="id2">Compiling with LLVMC</a></li> +<li><a class="reference internal" href="#using-the-llvmc-program" id="id2">Using the <tt class="docutils literal">llvmc</tt> program</a></li> <li><a class="reference internal" href="#using-llvmc-to-generate-toolchain-drivers" id="id3">Using LLVMC to generate toolchain drivers</a></li> </ul> </div> @@ -26,51 +26,47 @@ The ReST source lives in the directory 'tools/llvmc/doc'. --> <p>Written by <a href="mailto:foldr@codedgers.com">Mikhail Glushenkov</a></p> </div><div class="section" id="introduction"> <h1><a class="toc-backref" href="#id1">Introduction</a></h1> -<p>LLVMC is a generic compiler driver, which plays the same role for LLVM -as the <tt class="docutils literal"><span class="pre">gcc</span></tt> program does for GCC - the difference being that LLVMC -is designed to be more adaptable and easier to customize. Most of -LLVMC functionality is implemented via plugins, which can be loaded -dynamically or compiled in. This tutorial describes the basic usage -and configuration of LLVMC.</p> +<p>LLVMC is a generic compiler driver, which plays the same role for LLVM as the +<tt class="docutils literal">gcc</tt> program does for GCC - the difference being that LLVMC is designed to be +more adaptable and easier to customize. Most of LLVMC functionality is +implemented via high-level TableGen code, from which a corresponding C++ source +file is automatically generated. This tutorial describes the basic usage and +configuration of LLVMC.</p> </div> -<div class="section" id="compiling-with-llvmc"> -<h1><a class="toc-backref" href="#id2">Compiling with LLVMC</a></h1> -<p>In general, LLVMC tries to be command-line compatible with <tt class="docutils literal"><span class="pre">gcc</span></tt> as -much as possible, so most of the familiar options work:</p> +<div class="section" id="using-the-llvmc-program"> +<h1><a class="toc-backref" href="#id2">Using the <tt class="docutils literal">llvmc</tt> program</a></h1> +<p>In general, <tt class="docutils literal">llvmc</tt> tries to be command-line compatible with <tt class="docutils literal">gcc</tt> as much +as possible, so most of the familiar options work:</p> <pre class="literal-block"> $ llvmc -O3 -Wall hello.cpp $ ./a.out hello </pre> -<p>This will invoke <tt class="docutils literal"><span class="pre">llvm-g++</span></tt> under the hood (you can see which -commands are executed by using the <tt class="docutils literal"><span class="pre">-v</span></tt> option). For further help on -command-line LLVMC usage, refer to the <tt class="docutils literal"><span class="pre">llvmc</span> <span class="pre">--help</span></tt> output.</p> +<p>This will invoke <tt class="docutils literal"><span class="pre">llvm-g++</span></tt> under the hood (you can see which commands are +executed by using the <tt class="docutils literal"><span class="pre">-v</span></tt> option). For further help on command-line LLVMC +usage, refer to the <tt class="docutils literal">llvmc <span class="pre">--help</span></tt> output.</p> </div> <div class="section" id="using-llvmc-to-generate-toolchain-drivers"> <h1><a class="toc-backref" href="#id3">Using LLVMC to generate toolchain drivers</a></h1> -<p>LLVMC plugins are written mostly using <a class="reference external" href="http://llvm.org/docs/TableGenFundamentals.html">TableGen</a>, so you need to -be familiar with it to get anything done.</p> -<p>Start by compiling <tt class="docutils literal"><span class="pre">example/Simple</span></tt>, which is a primitive wrapper for -<tt class="docutils literal"><span class="pre">gcc</span></tt>:</p> +<p>LLVMC-based drivers are written mostly using <a class="reference external" href="http://llvm.org/docs/TableGenFundamentals.html">TableGen</a>, so you need to be +familiar with it to get anything done.</p> +<p>Start by compiling <tt class="docutils literal">example/Simple</tt>, which is a primitive wrapper for +<tt class="docutils literal">gcc</tt>:</p> <pre class="literal-block"> -$ cd $LLVM_DIR/tools/llvmc -$ cp -r example/Simple plugins/Simple - - # NB: A less verbose way to compile standalone LLVMC-based drivers is - # described in the reference manual. - -$ make LLVMC_BASED_DRIVER_NAME=mygcc LLVMC_BUILTIN_PLUGINS=Simple +$ cd $LLVM_OBJ_DIR/tools/examples/Simple +$ make $ cat > hello.c -[...] -$ mygcc hello.c +#include <stdio.h> +int main() { printf("Hello\n"); } +$ $LLVM_BIN_DIR/Simple -v hello.c +gcc hello.c -o hello.out $ ./hello.out Hello </pre> -<p>Here we link our plugin with the LLVMC core statically to form an executable -file called <tt class="docutils literal"><span class="pre">mygcc</span></tt>. It is also possible to build our plugin as a dynamic -library to be loaded by the <tt class="docutils literal"><span class="pre">llvmc</span></tt> executable (or any other LLVMC-based -standalone driver); this is described in the reference manual.</p> -<p>Contents of the file <tt class="docutils literal"><span class="pre">Simple.td</span></tt> look like this:</p> +<p>We have thus produced a simple driver called, appropriately, <tt class="docutils literal">Simple</tt>, from +the input TableGen file <tt class="docutils literal">Simple.td</tt>. The <tt class="docutils literal">llvmc</tt> program itself is generated +using a similar process (see <tt class="docutils literal">llvmc/src</tt>). Contents of the file <tt class="docutils literal">Simple.td</tt> +look like this:</p> <pre class="literal-block"> // Include common definitions include "llvm/CompilerDriver/Common.td" @@ -80,33 +76,36 @@ def gcc : Tool< [(in_language "c"), (out_language "executable"), (output_suffix "out"), - (cmd_line "gcc $INFILE -o $OUTFILE"), - (sink) + (command "gcc"), + (sink), + + // -o is what is used by default, out_file_option here is included for + // instructive purposes. + (out_file_option "-o") ]>; // Language map -def LanguageMap : LanguageMap<[LangToSuffixes<"c", ["c"]>]>; +def LanguageMap : LanguageMap<[(lang_to_suffixes "c", "c")]>; // Compilation graph -def CompilationGraph : CompilationGraph<[Edge<"root", "gcc">]>; +def CompilationGraph : CompilationGraph<[(edge "root", "gcc")]>; </pre> -<p>As you can see, this file consists of three parts: tool descriptions, -language map, and the compilation graph definition.</p> -<p>At the heart of LLVMC is the idea of a compilation graph: vertices in -this graph are tools, and edges represent a transformation path -between two tools (for example, assembly source produced by the -compiler can be transformed into executable code by an assembler). The -compilation graph is basically a list of edges; a special node named -<tt class="docutils literal"><span class="pre">root</span></tt> is used to mark graph entry points.</p> -<p>Tool descriptions are represented as property lists: most properties -in the example above should be self-explanatory; the <tt class="docutils literal"><span class="pre">sink</span></tt> property -means that all options lacking an explicit description should be -forwarded to this tool.</p> -<p>The <tt class="docutils literal"><span class="pre">LanguageMap</span></tt> associates a language name with a list of suffixes -and is used for deciding which toolchain corresponds to a given input -file.</p> -<p>To learn more about LLVMC customization, refer to the reference -manual and plugin source code in the <tt class="docutils literal"><span class="pre">plugins</span></tt> directory.</p> +<p>As you can see, this file consists of three parts: tool descriptions, language +map, and the compilation graph definition.</p> +<p>At the heart of LLVMC is the idea of a compilation graph: vertices in this graph +are tools, and edges represent a transformation path between two tools (for +example, assembly source produced by the compiler can be transformed into +executable code by an assembler). The compilation graph is basically a list of +edges; a special node named <tt class="docutils literal">root</tt> is used to mark graph entry points.</p> +<p>Tool descriptions are represented as property lists: most properties in the +example above should be self-explanatory; the <tt class="docutils literal">sink</tt> property means that all +options lacking an explicit description should be forwarded to this tool.</p> +<p>The <tt class="docutils literal">LanguageMap</tt> associates a language name with a list of suffixes and is +used for deciding which toolchain corresponds to a given input file.</p> +<p>To learn more about writing your own drivers with LLVMC, refer to the reference +manual and examples in the <tt class="docutils literal">examples</tt> directory. Of a particular interest is +the <tt class="docutils literal">Skeleton</tt> example, which can serve as a template for your LLVMC-based +drivers.</p> <hr /> <address> <a href="http://jigsaw.w3.org/css-validator/check/referer"> |
