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| author | Chris Lattner <sabre@nondot.org> | 2007-11-06 05:02:48 +0000 |
|---|---|---|
| committer | Chris Lattner <sabre@nondot.org> | 2007-11-06 05:02:48 +0000 |
| commit | 1d4dea3bcd8f1a78b3edee5cb566acc7b4359a90 (patch) | |
| tree | afd48e4bc628464a10776229e56d36cb0715b6fa /docs/tutorial/LangImpl1.html | |
| parent | f3920cbe6e4b8161f7d8878dec311020cf3eb74c (diff) | |
| download | external_llvm-1d4dea3bcd8f1a78b3edee5cb566acc7b4359a90.zip external_llvm-1d4dea3bcd8f1a78b3edee5cb566acc7b4359a90.tar.gz external_llvm-1d4dea3bcd8f1a78b3edee5cb566acc7b4359a90.tar.bz2 | |
Add a real intro to the series.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@43752 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'docs/tutorial/LangImpl1.html')
| -rw-r--r-- | docs/tutorial/LangImpl1.html | 103 |
1 files changed, 84 insertions, 19 deletions
diff --git a/docs/tutorial/LangImpl1.html b/docs/tutorial/LangImpl1.html index 2ce59b9..ee097ff 100644 --- a/docs/tutorial/LangImpl1.html +++ b/docs/tutorial/LangImpl1.html @@ -3,7 +3,7 @@ <html> <head> - <title>Kaleidoscope: The basic language, with its lexer</title> + <title>Kaleidoscope: Tutorial Introduction and the Lexer</title> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <meta name="author" content="Chris Lattner"> <link rel="stylesheet" href="../llvm.css" type="text/css"> @@ -11,7 +11,7 @@ <body> -<div class="doc_title">Kaleidoscope: The basic language, with its lexer</div> +<div class="doc_title">Kaleidoscope: Tutorial Introduction and the Lexer</div> <ul> <li><a href="index.html">Up to Tutorial Index</a></li> @@ -36,12 +36,88 @@ <div class="doc_text"> <p>Welcome to the "Implementing a language with LLVM" tutorial. This tutorial -will run the through implementation of a simple language, showing how fun and +runs through the implementation of a simple language, showing how fun and easy it can be. This tutorial will get you up and started as well as help to -build a framework you can extend to other languages. You can also use this -tutorial to help you start playing with other LLVM specific things. +build a framework you can extend to other languages, allowing you to use this +as a way to start playing with other LLVM specific things. </p> +<p> +The goal of this tutorial is to progressively unveil our language, describing +how it is built up over time. This will let us cover a fairly broad range of +language design and LLVM-specific usage issues, showing and explaining the code +for it all along the way, without overwhelming you with tons of details up +front.</p> + +<p>It is useful to point out ahead of time that this tutorial is really about +teaching compiler techniques and LLVM specifically, <em>not</em> about teaching +modern and sane software engineering principles. In practice, this means that +we'll take a number of shortcuts to simplify the exposition. For example, the +code leaks memory, uses global variables all over the place, doesn't use nice +design patterns like visitors, etc... but it is very simple. If you dig in and +use the code as a basis for future projects, fixing these deficiencies shouldn't +be hard.</p> + +<p>I've tried to put this tutorial together in a way that makes chapters easy to +skip over if you are already familiar or are uninterested with various pieces. +The structure of the tutorial is: +</p> + +<ul> +<li><b><a href="#language">Chapter #1</a>: Introduction to the Kaleidoscope +language, and the definition of its Lexer</b> - This shows where we are going +and the basic functionality that we want it to do. In order to make this +tutorial maximally understandable and hackable, we choose to implement +everything in C++ instead of using lexer and parser generators. LLVM obviously +works just fine with such tools, feel free to use one if you prefer.</li> +<li><b><a href="LangImpl2.html">Chapter #2</a>: Implementing a Parser and +AST</b> - With the lexer in place, we can talk about parsing techniques and +basic AST construction. This tutorial describes recursive descent parsing and +operator precedence parsing. Nothing in Chapters 1 or 2 is LLVM-specific, +the code doesn't even link in LLVM at this point. :)</li> +<li><b><a href="LangImpl3.html">Chapter #3</a>: Code generation to LLVM IR</b> - +With the AST ready, we can show off how easy generation of LLVM IR really +is.</li> +<li><b><a href="LangImpl4.html">Chapter #4</a>: Adding JIT and Optimizer +Support</b> - Because a lot of people are interested in using LLVM as a JIT, +we'll dive right into it and show you the 3 lines it takes to add JIT support. +LLVM is also useful in many other ways, but this is one simple and "sexy" way +that shows off its power. :)</li> +<li><b><a href="LangImpl5.html">Chapter #5</a>: Extending the Language: Control +Flow</b> - With the language up and running, we show how to extend it with +control flow operations (if/then/else and a for loop). This gives us a chance +to talk about simple SSA construction and control flow.</li> +<li><b><a href="LangImpl6.html">Chapter #6</a>: Extending the Language: +User-defined Operators</b> - This is a silly but fun chapter that talks about +extending the language to let the user program define their own arbitrary +unary and binary operators (with assignable precedence!). This lets us build a +significant piece of the "language" as library routines.</li> +<li><b><a href="LangImpl7.html">Chapter #7</a>: Extending the Language: Mutable +Variables</b> - This chapter talks about adding user-defined local variables +along with variable assignment operator. The interesting part about this is how +easy and trivial it is to construct SSA form in LLVM (no, LLVM does <em>not</em> +require your front-end to construct SSA form!).</li> +<li><b><a href="LangImpl8.html">Chapter #8</a>: Conclusion and other useful LLVM +tidbits</b> - This chapter wraps up the series by talking about potential +ways to extend the language, but also includes a bunch of pointers to info about +"special topics" like adding garbage collection support, exceptions, debugging, +support for "spaghetti stacks", and a bunch of other tips and tricks.</li> + +</ul> + +<p>By the end of the tutorial, we'll have written about 700 lines of +non-comment, non-blank lines of code. With this small amount of code, we'll +have built up a very reasonable compiler for a non-trivial language including +a hand-written lexer, parser, AST, as well as code generation support with a JIT +compiler. While other systems may have interesting "hello world" tutorials, +I think the breadth of this tutorial is a great testament to the strengths of +LLVM and why you should consider it if you're interested in language or compiler +design.</p> + +<p>A note about this tutorial: we expect you to extend the language and play +with it on your own. Take the code and go crazy hacking away at it. It can be +a lot of fun to play with languages! In any case, lets get into the code!</p> + </div> <!-- *********************************************************************** --> @@ -93,20 +169,9 @@ atan2(sin(.4), cos(42)) </pre> </div> -<p>In the first incarnation of the language, we will only support basic -arithmetic: if/then/else will be added in a future installment. Another -interesting aspect of the first implementation is that it is a completely -functional language, which does not allow you to have side-effects, etc. We -will eventually add side effects for those who prefer them.</p> - -<p>In order to make this tutorial -maximally understandable and hackable, we choose to implement everything in C++ -instead of using lexer and parser generators. LLVM obviously works just fine -with such tools, and making use of them doesn't impact the overall design.</p> - -<p>A note about this tutorial: we expect you to extend the language and play -with it on your own. Take the code and go crazy hacking away at it. It can be -a lot of fun to play with languages!</p> +<p>A more interesting example is included in Chapter 6 where we show the code +used to <a href="LangImpl6.html#example">implement a Mandelbrot Set viewer</a> +in Kaleidoscope.</p> </div> |