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5 <link rel="stylesheet" href="llvm.css" type="text/css">
6 <title>A Few Coding Standards</title>
7</head>
8<body>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]9
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]10<div class="doc_title">
11 A Few Coding Standards
12</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]13
14<ol>
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]15 <li><a href="#introduction">Introduction</a></li>
Chris Lattner7ae36bb2001-07-23 20:40:41 +0000[diff] [blame]16 <li><a href="#mechanicalissues">Mechanical Source Issues</a>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]17 <ol>
18 <li><a href="#sourceformating">Source Code Formatting</a>
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]19 <ol>
20 <li><a href="#scf_commenting">Commenting</a></li>
21 <li><a href="#scf_commentformat">Comment Formatting</a></li>
Misha Brukman91d64af2004-10-26 16:18:43 +0000[diff] [blame]22 <li><a href="#scf_includes"><tt>#include</tt> Style</a></li>
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]23 <li><a href="#scf_codewidth">Source Code Width</a></li>
24 <li><a href="#scf_spacestabs">Use Spaces Instead of Tabs</a></li>
25 <li><a href="#scf_indentation">Indent Code Consistently</a></li>
26 </ol></li>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]27 <li><a href="#compilerissues">Compiler Issues</a>
28 <ol>
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]29 <li><a href="#ci_warningerrors">Treat Compiler Warnings Like
30 Errors</a></li>
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]31 <li><a href="#ci_portable_code">Write Portable Code</a></li>
Reid Spencerb40df562004-09-23 16:03:48 +0000[diff] [blame]32 <li><a href="#ci_class_struct">Use of class/struct Keywords</a></li>
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]33 </ol></li>
34 </ol></li>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]35 <li><a href="#styleissues">Style Issues</a>
36 <ol>
37 <li><a href="#macro">The High Level Issues</a>
38 <ol>
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]39 <li><a href="#hl_module">A Public Header File <b>is</b> a
40 Module</a></li>
41 <li><a href="#hl_dontinclude">#include as Little as Possible</a></li>
42 <li><a href="#hl_privateheaders">Keep "internal" Headers
43 Private</a></li>
44 </ol></li>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]45 <li><a href="#micro">The Low Level Issues</a>
46 <ol>
Chris Lattner6883a882006-07-27 04:24:14 +0000[diff] [blame]47 <li><a href="#ll_assert">Assert Liberally</a></li>
48 <li><a href="#ll_ns_std">Do not use 'using namespace std'</a></li>
49 <li><a href="#ll_virtual_anch">Provide a virtual method anchor for clases in headers</a></li>
50 <li><a href="#ll_preincrement">Prefer Preincrement</a></li>
51 <li><a href="#ll_avoidendl">Avoid <tt>std::endl</tt></a></li>
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]52 </ol></li>
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]53 </ol></li>
54 <li><a href="#seealso">See Also</a></li>
55</ol>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]56
Chris Lattner999cf092004-05-23 21:05:07 +0000[diff] [blame]57<div class="doc_author">
58 <p>Written by <a href="mailto:sabre@nondot.org">Chris Lattner</a></p>
59</div>
60
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]61
62<!-- *********************************************************************** -->
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]63<div class="doc_section">
64 <a name="introduction">Introduction</a>
65</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]66<!-- *********************************************************************** -->
67
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]68<div class="doc_text">
69
70<p>This document attempts to describe a few coding standards that are being used
71in the LLVM source tree. Although no coding standards should be regarded as
Misha Brukman1b36d672003-10-06 19:26:00 +0000[diff] [blame]72absolute requirements to be followed in all instances, coding standards can be
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]73useful.</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]74
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]75<p>This document intentionally does not prescribe fixed standards for religious
Misha Brukman1b36d672003-10-06 19:26:00 +0000[diff] [blame]76issues such as brace placement and space usage. For issues like this, follow
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]77the golden rule:</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]78
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]79<blockquote>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]80
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]81<p><b><a name="goldenrule">If you are adding a significant body of source to a
82project, feel free to use whatever style you are most comfortable with. If you
83are extending, enhancing, or bug fixing already implemented code, use the style
84that is already being used so that the source is uniform and easy to
85follow.</a></b></p>
86
87</blockquote>
88
89<p>The ultimate goal of these guidelines is the increase readability and
Misha Brukman1b36d672003-10-06 19:26:00 +0000[diff] [blame]90maintainability of our common source base. If you have suggestions for topics to
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]91be included, please mail them to <a
92href="mailto:sabre@nondot.org">Chris</a>.</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]93
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]94</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]95
96<!-- *********************************************************************** -->
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]97<div class="doc_section">
98 <a name="mechanicalissues">Mechanical Source Issues</a>
99</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]100<!-- *********************************************************************** -->
101
102<!-- ======================================================================= -->
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]103<div class="doc_subsection">
104 <a name="sourceformating">Source Code Formatting</a>
105</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]106
107<!-- _______________________________________________________________________ -->
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]108<div class="doc_subsubsection">
109 <a name="scf_commenting">Commenting</a>
110</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]111
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]112<div class="doc_text">
113
114<p>Comments are one critical part of readability and maintainability. Everyone
Misha Brukman3b53a262004-12-04 00:32:12 +0000[diff] [blame]115knows they should comment, so should you. Although we all should probably
Misha Brukman1b36d672003-10-06 19:26:00 +0000[diff] [blame]116comment our code more than we do, there are a few very critical places that
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]117documentation is very useful:</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]118
Chris Lattner999cf092004-05-23 21:05:07 +0000[diff] [blame]119<b>File Headers</b>
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]120
121<p>Every source file should have a header on it that
122describes the basic purpose of the file. If a file does not have a header, it
123should not be checked into CVS. Most source trees will probably have a standard
124file header format. The standard format for the LLVM source tree looks like
125this:</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]126
Misha Brukmana8c760a2004-07-28 22:31:54 +0000[diff] [blame]127<div class="doc_code">
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]128<pre>
Chris Lattnerc49fcd12003-10-13 14:58:11 +0000[diff] [blame]129//===-- llvm/Instruction.h - Instruction class definition -------*- C++ -*-===//
Chris Lattner999cf092004-05-23 21:05:07 +0000[diff] [blame]130//
131// The LLVM Compiler Infrastructure
132//
133// This file was developed by the LLVM research group and is distributed under
134// the University of Illinois Open Source License. See LICENSE.TXT for details.
135//
136//===----------------------------------------------------------------------===//
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]137//
138// This file contains the declaration of the Instruction class, which is the
139// base class for all of the VM instructions.
140//
141//===----------------------------------------------------------------------===//
142</pre>
Misha Brukmana8c760a2004-07-28 22:31:54 +0000[diff] [blame]143</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]144
Chris Lattner999cf092004-05-23 21:05:07 +0000[diff] [blame]145<p>A few things to note about this particular format: The "<tt>-*- C++
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]146-*-</tt>" string on the first line is there to tell Emacs that the source file
Misha Brukman69c58892004-07-28 22:37:57 +0000[diff] [blame]147is a C++ file, not a C file (Emacs assumes .h files are C files by default).
148Note that this tag is not necessary in .cpp files. The name of the file is also
149on the first line, along with a very short description of the purpose of the
150file. This is important when printing out code and flipping though lots of
151pages.</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]152
Chris Lattner999cf092004-05-23 21:05:07 +0000[diff] [blame]153<p>The next section in the file is a concise note that defines the license that
154the file is released under. This makes it perfectly clear what terms the source
155code can be distributed under.</p>
156
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]157<p>The main body of the description does not have to be very long in most cases.
Misha Brukman1b36d672003-10-06 19:26:00 +0000[diff] [blame]158Here it's only two lines. If an algorithm is being implemented or something
159tricky is going on, a reference to the paper where it is published should be
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]160included, as well as any notes or "gotchas" in the code to watch out for.</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]161
Chris Lattner999cf092004-05-23 21:05:07 +0000[diff] [blame]162<b>Class overviews</b>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]163
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]164<p>Classes are one fundemental part of a good object oriented design. As such,
165a class definition should have a comment block that explains what the class is
Misha Brukman1b36d672003-10-06 19:26:00 +0000[diff] [blame]166used for... if it's not obvious. If it's so completely obvious your grandma
167could figure it out, it's probably safe to leave it out. Naming classes
Misha Brukman3b53a262004-12-04 00:32:12 +0000[diff] [blame]168something sane goes a long ways towards avoiding writing documentation.</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]169
170
Chris Lattner999cf092004-05-23 21:05:07 +0000[diff] [blame]171<b>Method information</b>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]172
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]173<p>Methods defined in a class (as well as any global functions) should also be
Misha Brukman1b36d672003-10-06 19:26:00 +0000[diff] [blame]174documented properly. A quick note about what it does any a description of the
175borderline behaviour is all that is necessary here (unless something
176particularly tricky or insideous is going on). The hope is that people can
177figure out how to use your interfaces without reading the code itself... that is
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]178the goal metric.</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]179
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]180<p>Good things to talk about here are what happens when something unexpected
181happens: does the method return null? Abort? Format your hard disk?</p>
182
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]183</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]184
185<!-- _______________________________________________________________________ -->
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]186<div class="doc_subsubsection">
187 <a name="scf_commentformat">Comment Formatting</a>
188</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]189
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]190<div class="doc_text">
191
192<p>In general, prefer C++ style (<tt>//</tt>) comments. They take less space,
Misha Brukman1b36d672003-10-06 19:26:00 +0000[diff] [blame]193require less typing, don't have nesting problems, etc. There are a few cases
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]194when it is useful to use C style (<tt>/* */</tt>) comments however:</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]195
196<ol>
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]197 <li>When writing a C code: Obviously if you are writing C code, use C style
Misha Brukman3b53a262004-12-04 00:32:12 +0000[diff] [blame]198 comments.</li>
Misha Brukman91d64af2004-10-26 16:18:43 +0000[diff] [blame]199 <li>When writing a header file that may be <tt>#include</tt>d by a C source
200 file.</li>
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]201 <li>When writing a source file that is used by a tool that only accepts C
202 style comments.</li>
203</ol>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]204
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]205<p>To comment out a large block of code, use <tt>#if 0</tt> and <tt>#endif</tt>.
206These nest properly and are better behaved in general than C style comments.</p>
207
208</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]209
Chris Lattner2e5cbc22003-08-07 21:45:47 +0000[diff] [blame]210<!-- _______________________________________________________________________ -->
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]211<div class="doc_subsubsection">
Misha Brukman91d64af2004-10-26 16:18:43 +0000[diff] [blame]212 <a name="scf_includes"><tt>#include</tt> Style</a>
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]213</div>
Chris Lattner2e5cbc22003-08-07 21:45:47 +0000[diff] [blame]214
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]215<div class="doc_text">
216
217<p>Immediately after the <a href="#scf_commenting">header file comment</a> (and
Chris Lattner2e5cbc22003-08-07 21:45:47 +0000[diff] [blame]218include guards if working on a header file), the <a
Misha Brukmana8c760a2004-07-28 22:31:54 +0000[diff] [blame]219href="#hl_dontinclude">minimal</a> list of <tt>#include</tt>s required by the
220file should be listed. We prefer these <tt>#include</tt>s to be listed in this
221order:</p>
Chris Lattner2e5cbc22003-08-07 21:45:47 +0000[diff] [blame]222
223<ol>
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]224 <li><a href="#mmheader">Main Module header</a></li>
225 <li><a href="#hl_privateheaders">Local/Private Headers</a></li>
Misha Brukmana8c760a2004-07-28 22:31:54 +0000[diff] [blame]226 <li><tt>llvm/*</tt></li>
227 <li><tt>llvm/Analysis/*</tt></li>
228 <li><tt>llvm/Assembly/*</tt></li>
229 <li><tt>llvm/Bytecode/*</tt></li>
230 <li><tt>llvm/CodeGen/*</tt></li>
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]231 <li>...</li>
Misha Brukmana8c760a2004-07-28 22:31:54 +0000[diff] [blame]232 <li><tt>Support/*</tt></li>
233 <li><tt>Config/*</tt></li>
234 <li>System <tt>#includes</tt></li>
Chris Lattner2e5cbc22003-08-07 21:45:47 +0000[diff] [blame]235</ol>
236
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]237<p>... and each catagory should be sorted by name.</p>
Chris Lattner2e5cbc22003-08-07 21:45:47 +0000[diff] [blame]238
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]239<p><a name="mmheader">The "Main Module Header"</a> file applies to .cpp file
Misha Brukman91d64af2004-10-26 16:18:43 +0000[diff] [blame]240which implement an interface defined by a .h file. This <tt>#include</tt>
241should always be included <b>first</b> regardless of where it lives on the file
242system. By including a header file first in the .cpp files that implement the
243interfaces, we ensure that the header does not have any hidden dependencies
244which are not explicitly #included in the header, but should be. It is also a
245form of documentation in the .cpp file to indicate where the interfaces it
246implements are defined.</p>
Chris Lattner2e5cbc22003-08-07 21:45:47 +0000[diff] [blame]247
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]248</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]249
250<!-- _______________________________________________________________________ -->
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]251<div class="doc_subsubsection">
252 <a name="scf_codewidth">Source Code Width</a>
253</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]254
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]255<div class="doc_text">
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]256
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]257<p>Write your code to fit within 80 columns of text. This helps those of us who
258like to print out code and look at your code in an xterm without resizing
259it.</p>
260
261</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]262
263<!-- _______________________________________________________________________ -->
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]264<div class="doc_subsubsection">
265 <a name="scf_spacestabs">Use Spaces Instead of Tabs</a>
266</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]267
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]268<div class="doc_text">
269
270<p>In all cases, prefer spaces to tabs in source files. People have different
Misha Brukman1b36d672003-10-06 19:26:00 +0000[diff] [blame]271prefered indentation levels, and different styles of indentation that they
272like... this is fine. What isn't is that different editors/viewers expand tabs
273out to different tab stops. This can cause your code to look completely
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]274unreadable, and it is not worth dealing with.</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]275
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]276<p>As always, follow the <a href="#goldenrule">Golden Rule</a> above: follow the
Misha Brukman1b36d672003-10-06 19:26:00 +0000[diff] [blame]277style of existing code if your are modifying and extending it. If you like four
278spaces of indentation, <b>DO NOT</b> do that in the middle of a chunk of code
279with two spaces of indentation. Also, do not reindent a whole source file: it
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]280makes for incredible diffs that are absolutely worthless.</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]281
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]282</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]283
284<!-- _______________________________________________________________________ -->
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]285<div class="doc_subsubsection">
286 <a name="scf_indentation">Indent Code Consistently</a>
287</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]288
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]289<div class="doc_text">
290
291<p>Okay, your first year of programming you were told that indentation is
Misha Brukman1b36d672003-10-06 19:26:00 +0000[diff] [blame]292important. If you didn't believe and internalize this then, now is the time.
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]293Just do it.</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]294
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]295</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]296
297
298<!-- ======================================================================= -->
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]299<div class="doc_subsection">
300 <a name="compilerissues">Compiler Issues</a>
301</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]302
303
304<!-- _______________________________________________________________________ -->
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]305<div class="doc_subsubsection">
306 <a name="ci_warningerrors">Treat Compiler Warnings Like Errors</a>
307</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]308
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]309<div class="doc_text">
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]310
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]311<p>If your code has compiler warnings in it, something is wrong: you aren't
312casting values correctly, your have "questionable" constructs in your code, or
313you are doing something legitimately wrong. Compiler warnings can cover up
314legitimate errors in output and make dealing with a translation unit
315difficult.</p>
316
317<p>It is not possible to prevent all warnings from all compilers, nor is it
Misha Brukman1b36d672003-10-06 19:26:00 +0000[diff] [blame]318desirable. Instead, pick a standard compiler (like <tt>gcc</tt>) that provides
319a good thorough set of warnings, and stick to them. At least in the case of
320<tt>gcc</tt>, it is possible to work around any spurious errors by changing the
321syntax of the code slightly. For example, an warning that annoys me occurs when
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]322I write code like this:</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]323
Misha Brukmana8c760a2004-07-28 22:31:54 +0000[diff] [blame]324<div class="doc_code">
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]325<pre>
Misha Brukmana8c760a2004-07-28 22:31:54 +0000[diff] [blame]326if (V = getValue()) {
327 ...
328}
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]329</pre>
Misha Brukmana8c760a2004-07-28 22:31:54 +0000[diff] [blame]330</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]331
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]332<p><tt>gcc</tt> will warn me that I probably want to use the <tt>==</tt>
333operator, and that I probably mistyped it. In most cases, I haven't, and I
334really don't want the spurious errors. To fix this particular problem, I
335rewrite the code like this:</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]336
Misha Brukmana8c760a2004-07-28 22:31:54 +0000[diff] [blame]337<div class="doc_code">
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]338<pre>
Misha Brukmana8c760a2004-07-28 22:31:54 +0000[diff] [blame]339if ((V = getValue())) {
340 ...
341}
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]342</pre>
Misha Brukmana8c760a2004-07-28 22:31:54 +0000[diff] [blame]343</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]344
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]345<p>...which shuts <tt>gcc</tt> up. Any <tt>gcc</tt> warning that annoys you can
346be fixed by massaging the code appropriately.</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]347
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]348<p>These are the <tt>gcc</tt> warnings that I prefer to enable: <tt>-Wall
349-Winline -W -Wwrite-strings -Wno-unused</tt></p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]350
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]351</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]352
353<!-- _______________________________________________________________________ -->
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]354<div class="doc_subsubsection">
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]355 <a name="ci_portable_code">Write Portable Code</a>
356</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]357
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]358<div class="doc_text">
359
360<p>In almost all cases, it is possible and within reason to write completely
Misha Brukman2d10d752003-07-28 21:57:18 +0000[diff] [blame]361portable code. If there are cases where it isn't possible to write portable
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]362code, isolate it behind a well defined (and well documented) interface.</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]363
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]364<p>In practice, this means that you shouldn't assume much about the host
365compiler, including its support for "high tech" features like partial
366specialization of templates. In fact, Visual C++ 6 could be an important target
367for our work in the future, and we don't want to have to rewrite all of our code
368to support it.</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]369
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]370</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]371
Reid Spencerb40df562004-09-23 16:03:48 +0000[diff] [blame]372<!-- _______________________________________________________________________ -->
373<div class="doc_subsubsection">
374<a name="ci_class_struct">Use of <tt>class</tt> and <tt>struct</tt> Keywords</a>
375</div>
376<div class="doc_text">
Misha Brukmanedcc78a2004-10-26 15:45:13 +0000[diff] [blame]377
378<p>In C++, the <tt>class</tt> and <tt>struct</tt> keywords can be used almost
379interchangeably. The only difference is when they are used to declare a class:
380<tt>class</tt> makes all members private by default while <tt>struct</tt> makes
381all members public by default.</p>
382
383<p>Unfortunately, not all compilers follow the rules and some will generate
384different symbols based on whether <tt>class</tt> or <tt>struct</tt> was used to
385declare the symbol. This can lead to problems at link time.</p>
386
387<p>So, the rule for LLVM is to always use the <tt>class</tt> keyword, unless
388<b>all</b> members are public, in which case <tt>struct</tt> is allowed.</p>
389
Reid Spencerb40df562004-09-23 16:03:48 +0000[diff] [blame]390</div>
391
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]392<!-- *********************************************************************** -->
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]393<div class="doc_section">
394 <a name="styleissues">Style Issues</a>
395</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]396<!-- *********************************************************************** -->
397
398
399<!-- ======================================================================= -->
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]400<div class="doc_subsection">
401 <a name="macro">The High Level Issues</a>
402</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]403
404
405<!-- _______________________________________________________________________ -->
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]406<div class="doc_subsubsection">
407 <a name="hl_module">A Public Header File <b>is</b> a Module</a>
408</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]409
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]410<div class="doc_text">
411
412<p>C++ doesn't do too well in the modularity department. There is no real
Misha Brukman2d10d752003-07-28 21:57:18 +0000[diff] [blame]413encapsulation or data hiding (unless you use expensive protocol classes), but it
414is what we have to work with. When you write a public header file (in the LLVM
415source tree, they live in the top level "include" directory), you are defining a
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]416module of functionality.</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]417
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]418<p>Ideally, modules should be completely independent of each other, and their
Misha Brukman2d10d752003-07-28 21:57:18 +0000[diff] [blame]419header files should only include the absolute minimum number of headers
420possible. A module is not just a class, a function, or a namespace: <a
421href="http://www.cuj.com/articles/2000/0002/0002c/0002c.htm">it's a collection
422of these</a> that defines an interface. This interface may be several
423functions, classes or data structures, but the important issue is how they work
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]424together.</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]425
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]426<p>In general, a module should be implemented with one or more <tt>.cpp</tt>
427files. Each of these <tt>.cpp</tt> files should include the header that defines
428their interface first. This ensure that all of the dependences of the module
429header have been properly added to the module header itself, and are not
430implicit. System headers should be included after user headers for a
431translation unit.</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]432
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]433</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]434
435<!-- _______________________________________________________________________ -->
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]436<div class="doc_subsubsection">
Misha Brukman91d64af2004-10-26 16:18:43 +0000[diff] [blame]437 <a name="hl_dontinclude"><tt>#include</tt> as Little as Possible</a>
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]438</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]439
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]440<div class="doc_text">
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]441
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]442<p><tt>#include</tt> hurts compile time performance. Don't do it unless you
443have to, especially in header files.</p>
444
445<p>But wait, sometimes you need to have the definition of a class to use it, or
Misha Brukman91d64af2004-10-26 16:18:43 +0000[diff] [blame]446to inherit from it. In these cases go ahead and <tt>#include</tt> that header
447file. Be aware however that there are many cases where you don't need to have
448the full definition of a class. If you are using a pointer or reference to a
449class, you don't need the header file. If you are simply returning a class
450instance from a prototyped function or method, you don't need it. In fact, for
451most cases, you simply don't need the definition of a class... and not
452<tt>#include</tt>'ing speeds up compilation.</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]453
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]454<p>It is easy to try to go too overboard on this recommendation, however. You
Misha Brukman2d10d752003-07-28 21:57:18 +0000[diff] [blame]455<b>must</b> include all of the header files that you are using, either directly
456or indirectly (through another header file). To make sure that you don't
457accidently forget to include a header file in your module header, make sure to
458include your module header <b>first</b> in the implementation file (as mentioned
459above). This way there won't be any hidden dependencies that you'll find out
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]460about later...</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]461
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]462</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]463
464<!-- _______________________________________________________________________ -->
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]465<div class="doc_subsubsection">
466 <a name="hl_privateheaders">Keep "internal" Headers Private</a>
467</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]468
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]469<div class="doc_text">
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]470
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]471<p>Many modules have a complex implementation that causes them to use more than
472one implementation (<tt>.cpp</tt>) file. It is often tempting to put the
473internal communication interface (helper classes, extra functions, etc) in the
Misha Brukman3b53a262004-12-04 00:32:12 +0000[diff] [blame]474public module header file. Don't do this.</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]475
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]476<p>If you really need to do something like this, put a private header file in
477the same directory as the source files, and include it locally. This ensures
478that your private interface remains private and undisturbed by outsiders.</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]479
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]480<p>Note however, that it's okay to put extra implementation methods a public
481class itself... just make them private (or protected), and all is well.</p>
482
483</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]484
485<!-- ======================================================================= -->
Chris Lattner999cf092004-05-23 21:05:07 +0000[diff] [blame]486<div class="doc_subsection">
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]487 <a name="micro">The Low Level Issues</a>
488</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]489
490
491<!-- _______________________________________________________________________ -->
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]492<div class="doc_subsubsection">
Chris Lattner6883a882006-07-27 04:24:14 +0000[diff] [blame]493 <a name="ll_assert">Assert Liberally</a>
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]494</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]495
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]496<div class="doc_text">
497
498<p>Use the "<tt>assert</tt>" function to its fullest. Check all of your
Misha Brukman2d10d752003-07-28 21:57:18 +0000[diff] [blame]499preconditions and assumptions, you never know when a bug (not neccesarily even
500yours) might be caught early by an assertion, which reduces debugging time
501dramatically. The "<tt>&lt;cassert&gt;</tt>" header file is probably already
502included by the header files you are using, so it doesn't cost anything to use
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]503it.</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]504
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]505<p>To further assist with debugging, make sure to put some kind of error message
506in the assertion statement (which is printed if the assertion is tripped). This
Misha Brukman2d10d752003-07-28 21:57:18 +0000[diff] [blame]507helps the poor debugging make sense of why an assertion is being made and
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]508enforced, and hopefully what to do about it. Here is one complete example:</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]509
Misha Brukmana8c760a2004-07-28 22:31:54 +0000[diff] [blame]510<div class="doc_code">
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]511<pre>
Misha Brukmana8c760a2004-07-28 22:31:54 +0000[diff] [blame]512inline Value *getOperand(unsigned i) {
513 assert(i &lt; Operands.size() &amp;&amp; "getOperand() out of range!");
514 return Operands[i];
515}
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]516</pre>
Misha Brukmana8c760a2004-07-28 22:31:54 +0000[diff] [blame]517</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]518
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]519<p>Here are some examples:</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]520
Misha Brukmana8c760a2004-07-28 22:31:54 +0000[diff] [blame]521<div class="doc_code">
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]522<pre>
Misha Brukmana8c760a2004-07-28 22:31:54 +0000[diff] [blame]523assert(Ty-&gt;isPointerType() &amp;&amp; "Can't allocate a non pointer type!");
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]524
Misha Brukmana8c760a2004-07-28 22:31:54 +0000[diff] [blame]525assert((Opcode == Shl || Opcode == Shr) &amp;&amp; "ShiftInst Opcode invalid!");
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]526
Misha Brukmana8c760a2004-07-28 22:31:54 +0000[diff] [blame]527assert(idx &lt; getNumSuccessors() &amp;&amp; "Successor # out of range!");
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]528
Misha Brukmana8c760a2004-07-28 22:31:54 +0000[diff] [blame]529assert(V1.getType() == V2.getType() &amp;&amp; "Constant types must be identical!");
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]530
Misha Brukmana8c760a2004-07-28 22:31:54 +0000[diff] [blame]531assert(isa&lt;PHINode&gt;(Succ-&gt;front()) &amp;&amp; "Only works on PHId BBs!");
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]532</pre>
Misha Brukmana8c760a2004-07-28 22:31:54 +0000[diff] [blame]533</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]534
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]535<p>You get the idea...</p>
536
537</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]538
Chris Lattnerb0bff9e2006-01-01 21:59:22 +0000[diff] [blame]539<!-- _______________________________________________________________________ -->
540<div class="doc_subsubsection">
Chris Lattner6883a882006-07-27 04:24:14 +0000[diff] [blame]541 <a name="ll_ns_std">Do not use 'using namespace std'</a>
Chris Lattnerb0bff9e2006-01-01 21:59:22 +0000[diff] [blame]542</div>
543
544<div class="doc_text">
545<p>In LLVM, we prefer to explicitly prefix all identifiers from the standard
546namespace with an "std::" prefix, rather than rely on "using namespace std;".
547</p>
548
549<p> In header files, adding a 'using namespace XXX' directive pollutes the
550namespace of any source file that includes the header. This is clearly a bad
551thing.</p>
552
553<p>In implementation files (e.g. .cpp files) the rule is more of a stylistic
554rule, but is still important. Basically, using explicit namespace prefixes
555makes
556the code <b>more clear</b> - because it is immediately obvious what facilities
557are being used and where they are coming from - and <b>more portable</b> -
558because namespace clashes cannot occur between LLVM code and other namespaces.
559The portability rule is important because different standard library
560implementations expose different symbols (potentially ones they shouldn't) and
561future revisions to the C++ standard will add more symbols to the std
562namespace. As such, we never 'using namespace std;' in LLVM.</p>
563
564<p>The exception to the general rule (i.e. it's not an exception for the std
565namespace) is for implementation files. For example, all of the code in the
566LLVM project implements code that lives in the 'llvm' namespace. As such, it
567is ok, and actually more clear, for the .cpp files to have a 'using namespace
568llvm' directive at their top, after the #includes. The general form of this
569rule is that any .cpp file that implements code in any namespace may use that
570namespace (and its parents), but should not use any others.</p>
571
572</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]573
574<!-- _______________________________________________________________________ -->
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]575<div class="doc_subsubsection">
Chris Lattner6883a882006-07-27 04:24:14 +0000[diff] [blame]576 <a name="ll_virtual_anch">Provide a virtual method anchor for clases in headers</a>
577</div>
578
579<div class="doc_text">
580
581<p>If a class is defined in a header file and has a v-table (either it has
582virtual methods or it derives from classes with virtual methods), it must
583always have at least one out-of-line virtual method in the class. Without
584this, the compiler will copy the vtable and RTTI into every .o file that
585#includes the header, bloating .o file sizes and increasing link times.
586</p>
587
588</div>
589
590
591<!-- _______________________________________________________________________ -->
592<div class="doc_subsubsection">
593 <a name="ll_preincrement">Prefer Preincrement</a>
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]594</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]595
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]596<div class="doc_text">
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]597
Misha Brukmana8c760a2004-07-28 22:31:54 +0000[diff] [blame]598<p>Hard fast rule: Preincrement (<tt>++X</tt>) may be no slower than
599postincrement (<tt>X++</tt>) and could very well be a lot faster than it. Use
600preincrementation whenever possible.</p>
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]601
602<p>The semantics of postincrement include making a copy of the value being
Misha Brukman2d10d752003-07-28 21:57:18 +0000[diff] [blame]603incremented, returning it, and then preincrementing the "work value". For
604primitive types, this isn't a big deal... but for iterators, it can be a huge
605issue (for example, some iterators contains stack and set objects in them...
606copying an iterator could invoke the copy ctor's of these as well). In general,
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]607get in the habit of always using preincrement, and you won't have a problem.</p>
608
609</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]610
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]611<!-- _______________________________________________________________________ -->
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]612<div class="doc_subsubsection">
Chris Lattner6883a882006-07-27 04:24:14 +0000[diff] [blame]613 <a name="ll_avoidendl">Avoid <tt>std::endl</tt></a>
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]614</div>
Chris Lattner13c46592002-01-20 19:01:26 +0000[diff] [blame]615
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]616<div class="doc_text">
617
Chris Lattner999cf092004-05-23 21:05:07 +0000[diff] [blame]618<p>The <tt>std::endl</tt> modifier, when used with iostreams outputs a newline
619to the output stream specified. In addition to doing this, however, it also
620flushes the output stream. In other words, these are equivalent:</p>
Chris Lattner13c46592002-01-20 19:01:26 +0000[diff] [blame]621
Misha Brukmana8c760a2004-07-28 22:31:54 +0000[diff] [blame]622<div class="doc_code">
Chris Lattner13c46592002-01-20 19:01:26 +0000[diff] [blame]623<pre>
Misha Brukmana8c760a2004-07-28 22:31:54 +0000[diff] [blame]624std::cout &lt;&lt; std::endl;
625std::cout &lt;&lt; '\n' &lt;&lt; std::flush;
Chris Lattner13c46592002-01-20 19:01:26 +0000[diff] [blame]626</pre>
Misha Brukmana8c760a2004-07-28 22:31:54 +0000[diff] [blame]627</div>
Chris Lattner13c46592002-01-20 19:01:26 +0000[diff] [blame]628
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]629<p>Most of the time, you probably have no reason to flush the output stream, so
Misha Brukmana8c760a2004-07-28 22:31:54 +0000[diff] [blame]630it's better to use a literal <tt>'\n'</tt>.</p>
Chris Lattner13c46592002-01-20 19:01:26 +0000[diff] [blame]631
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]632</div>
Chris Lattner13c46592002-01-20 19:01:26 +0000[diff] [blame]633
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]634<!-- *********************************************************************** -->
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]635<div class="doc_section">
636 <a name="seealso">See Also</a>
637</div>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]638<!-- *********************************************************************** -->
639
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]640<div class="doc_text">
641
642<p>A lot of these comments and recommendations have been culled for other
643sources. Two particularly important books for our work are:</p>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]644
645<ol>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]646
Tanya Lattner09cf73c2004-06-22 04:24:55 +0000[diff] [blame]647<li><a href="http://www.aw-bc.com/catalog/academic/product/0,1144,0201310155,00.html">Effective
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]648C++</a> by Scott Meyers. There is an online version of the book (only some
649chapters though) <a
Chris Lattner999cf092004-05-23 21:05:07 +0000[diff] [blame]650href="http://www.awlonline.com/cseng/meyerscddemo/">available as well</a>. Also
651interesting and useful are "More Effective C++" and "Effective STL" by the same
652author.</li>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]653
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]654<li><a href="http://cseng.aw.com/book/0,3828,0201633620,00.html">Large-Scale C++
655Software Design</a> by John Lakos</li>
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]656
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]657</ol>
658
659<p>If you get some free time, and you haven't read them: do so, you might learn
Misha Brukman3b53a262004-12-04 00:32:12 +0000[diff] [blame]660something.</p>
Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]661
662</div>
663
Chris Lattnerd80c43c2001-07-09 03:27:08 +0000[diff] [blame]664<!-- *********************************************************************** -->
665
666<hr>
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Misha Brukman75f258e2003-10-24 17:57:33 +0000[diff] [blame]672
Misha Brukman6c16c4b2004-05-12 18:37:22 +0000[diff] [blame]673 <a href="mailto:sabre@nondot.org">Chris Lattner</a><br>
Reid Spencer05fe4b02006-03-14 05:39:39 +0000[diff] [blame]674 <a href="http://llvm.org">LLVM Compiler Infrastructure</a><br>
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