Gitiles
Code Review Sign In
gerrit-public.fairphone.software / fp2-dev / platform / external / llvm / 6a7ccea3dadb53ad3f003c27e3da10014fe57311 / . / docs / GettingStarted.html
blob: 3b556564732a317abbc643badaf435491a018592 [file] [log] [blame]
Guochun Shif4688a82002-07-17 23:05:56 +0000[diff] [blame]1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
2<html>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]3 <head>
4 <title>Getting Started with LLVM System</title>
5 </head>
6
7 <body bgcolor=white>
8 <center><h1>Getting Started with the LLVM System<br><font size=3>By: <a
9 href="mailto:gshi1@uiuc.edu">Guochun Shi</a>,
John Criswellcb27f1e2003-07-01 21:55:57 +0000[diff] [blame]10 <a href="mailto:sabre@nondot.org">Chris Lattner</a>,
Misha Brukmanc103adf2003-08-11 18:45:46 +0000[diff] [blame]11 <a href="mailto:criswell@uiuc.edu">John Criswell</a>,
12 <a href="http://misha.brukman.net">Misha Brukman</a>, and
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]13 <a href="http://www.cs.uiuc.edu/~vadve">Vikram Adve</a>
14 </font></h1></center>
15
16 <!--=====================================================================-->
17 <h2><a name="Contents">Contents</a></h2>
18 <!--=====================================================================-->
19
20 <ul>
21 <li><a href="#overview">Overview</a>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]22 <li><a href="#quickstart">Getting Started Quickly (A Summary)</a>
John Criswell3ab71362003-10-20 16:39:52 +0000[diff] [blame]23 <li><a href="#requirements">Requirements</a>
24 <ol>
25 <li><a href="#hardware">Hardware</a>
26 <li><a href="#software">Software</a>
27 </ol>
28
John Criswellabb1b582003-10-10 16:17:19 +0000[diff] [blame]29 <li><a href="#starting">Getting Started with LLVM</a>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]30 <ol>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]31 <li><a href="#terminology">Terminology and Notation</tt></a>
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]32 <li><a href="#environment">Setting Up Your Environment</a>
John Criswell312a68c2003-07-07 19:27:35 +0000[diff] [blame]33 <li><a href="#unpack">Unpacking the LLVM Archives</a>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]34 <li><a href="#checkout">Checkout LLVM from CVS</a>
John Criswellabb1b582003-10-10 16:17:19 +0000[diff] [blame]35 <li><a href="#installcf">Install the GCC Front End</a>
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]36 <li><a href="#config">Local LLVM Configuration</tt></a>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]37 <li><a href="#compile">Compiling the LLVM Suite Source Code</a>
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]38 <li><a href="#objfiles">The Location of LLVM Object Files</tt></a>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]39 </ol>
40 <li><a href="#layout">Program layout</a>
Misha Brukmanc103adf2003-08-11 18:45:46 +0000[diff] [blame]41 <ol>
42 <li><a href="#cvsdir"><tt>CVS</tt> directories</a>
43 <li><a href="#include"><tt>llvm/include</tt></a>
44 <li><a href="#lib"><tt>llvm/lib</tt></a>
John Criswellabb1b582003-10-10 16:17:19 +0000[diff] [blame]45 <li><a href="#runtime"><tt>llvm/runtime</tt></a>
Misha Brukmanc103adf2003-08-11 18:45:46 +0000[diff] [blame]46 <li><a href="#test"><tt>llvm/test</tt></a>
47 <li><a href="#tools"><tt>llvm/tools</tt></a>
48 <li><a href="#utils"><tt>llvm/utils</tt></a>
49 </ol>
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]50 <li><a href="#tutorial">An Example Using the LLVM Tool Chain</a>
51 <li><a href="#problems">Common Problems</a>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]52 <li><a href="#links">Links</a>
53 </ul>
54
55
56 <!--=====================================================================-->
57 <center>
58 <h2><a name="overview"><b>Overview</b></a></h2>
59 </center>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]60 <hr>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]61 <!--=====================================================================-->
62
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]63 Welcome to LLVM! In order to get started, you first need to know some
64 basic information.
65
66 <p>
67 First, LLVM comes in two pieces. The first piece is the LLVM suite. This
68 contains all of the tools, libraries, and header files needed to use the
John Criswell3ab71362003-10-20 16:39:52 +0000[diff] [blame]69 low level virtual machine. It contains an assembler, disassembler,
70 bytecode analyzer, and bytecode optimizer. It also contains a test suite
71 that can be used to test the LLVM tools and the GCC front end.
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]72 <p>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]73 The second piece is the GCC front end. This component provides a version
74 of GCC that compiles C and C++ code into LLVM bytecode. Currently, the
75 GCC front end is a modified version of GCC 3.4 (we track the GCC 3.4
76 development). Once compiled into LLVM bytecode, a program can be
77 manipulated with the LLVM tools from the LLVM suite.
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]78
79 <!--=====================================================================-->
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]80 <center>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]81 <h2><a name="quickstart"><b>Getting Started Quickly (A Summary)</b></a></h2>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]82 </center>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]83 <hr>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]84 <!--=====================================================================-->
85
86 Here's the short story for getting up and running quickly with LLVM:
Chris Lattner96768ea2003-02-14 04:22:13 +0000[diff] [blame]87 <ol>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]88 <li>Install the GCC front end:
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]89 <ol>
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]90 <li><tt>cd <i>where-you-want-the-C-front-end-to-live</i></tt>
91 <li><tt>gunzip --stdout cfrontend.<i>platform</i>.tar.gz | tar -xvf
92 -</tt>
93 </ol>
John Criswell7a73b802003-06-30 21:59:07 +0000[diff] [blame]94
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]95 <p>
96
97 <li>Get the Source Code
98 <ul>
99 <li>With the distributed files:
100 <ol>
101 <li><tt>cd <i>where-you-want-llvm-to-live</i></tt>
102 <li><tt>gunzip --stdout llvm.tar.gz | tar -xvf -</tt>
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]103 <li><tt>cd llvm</tt>
104 </ol>
105
106 <p>
107
108 <li>With anonymous CVS access:
109 <ol>
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]110 <li><tt>cd <i>where-you-want-llvm-to-live</i></tt>
John Criswelle04c2632003-10-21 21:24:38 +0000[diff] [blame]111 <li><tt>cvs -d :pserver:anon@llvm-cvs.cs.uiuc.edu:/var/cvs/llvm login</tt>
112 <li>Hit the return key when prompted for the password.
Chris Lattner70bb09b2003-10-23 19:49:01 +0000[diff] [blame]113 <li><tt>cvs -z3 -d :pserver:anon@llvm-cvs.cs.uiuc.edu:/var/cvs/llvm co llvm</tt>
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]114 <li><tt>cd llvm</tt>
115 </ol>
116 </ul>
117 </ul>
118
119 <p>
120
121 <li>Configure the LLVM Build Environment
122 <ol>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]123 <li>Change directory to where you want to store the LLVM object
124 files and run <tt>configure</tt> to configure the Makefiles and
125 header files for the default platform.
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]126 Useful options include:
127 <ul>
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]128 <li><tt>--with-llvmgccdir=<i>directory</i></tt>
129 <br>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]130 Specify where the LLVM GCC frontend is installed.
John Criswellabb1b582003-10-10 16:17:19 +0000[diff] [blame]131 <p>
132
133 <li><tt>--enable-spec2000=<i>directory</i></tt>
134 <br>
135 Enable the SPEC2000 benchmarks for testing. The SPEC2000
136 benchmarks should be available in <tt><i>directory</i></tt>.
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]137 </ul>
138 </ol>
139
140 <p>
141
142 <li>Build the LLVM Suite
143 <ol>
144 <li>Set your LLVM_LIB_SEARCH_PATH environment variable.
145 <li><tt>gmake -k |& tee gnumake.out
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]146 &nbsp;&nbsp;&nbsp;# this is csh or tcsh syntax</tt>
147 </ol>
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]148
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]149 <p>
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]150
Chris Lattner96768ea2003-02-14 04:22:13 +0000[diff] [blame]151 </ol>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]152
John Criswell3ab71362003-10-20 16:39:52 +0000[diff] [blame]153 <p>
154 Consult the <a href="starting">Getting Started with LLVM</a> section for
155 detailed information on configuring and compiling LLVM. See
156 <a href="#environment">Setting Up Your Environment</a> for tips that
157 simplify working with the GCC front end and LLVM tools. Go to
158 <a href="#layout">Program Layout</a> to learn about the layout of the
159 source code tree.
160
161 <!--=====================================================================-->
162 <center>
163 <h2><a name="requirements"><b>Requirements</b></a></h2>
164 </center>
165 <hr>
166 <!--=====================================================================-->
167
168 Before you begin to use the LLVM system, review the requirements given
169 below. This may save you some trouble by knowing ahead of time what
170 hardware and software you will need.
171
172 <!--=====================================================================-->
173 <h3><a name="hardware"><b>Hardware</b></a></h3>
174 <!--=====================================================================-->
175 LLVM is known to work on the following platforms:
176 <ul>
177 <li> Linux on x86 (Pentium and above)
178 <ul>
179 <li> Approximately 760 MB of Free Disk Space
180 <ul>
181 <li>Source code: 30 MB
182 <li>Object code: 670 MB
183 <li>GCC front end: 60 MB
184 </ul>
185 </ul>
186
187 <p>
188
189 <li> Solaris on SparcV9 (Ultrasparc)
190 <ul>
191 <li> Approximately 1.24 GB of Free Disk Space
192 <ul>
193 <li>Source code: 30 MB
194 <li>Object code: 1000 MB
195 <li>GCC front end: 210 MB
196 </ul>
197 </ul>
198 </ul>
199
200 The LLVM suite <i>may</i> compile on other platforms, but it is not
201 guaranteed to do so. If compilation is successful, the LLVM utilities
202 should be able to assemble, disassemble, analyze, and optimize LLVM
203 bytecode. Code generation should work as well, although the generated
204 native code may not work on your platform.
205 <p>
206 The GCC front end is not very portable at the moment. If you want to get
207 it to work on another platform, you can always request
208 <a href="mailto:llvm-request@zion.cs.uiuc.edu">a copy of the source</a>
209 and try to compile it on your platform.
210 </p>
211
212 <!--=====================================================================-->
213 <h3><a name="software"><b>Software</b></a></h3>
214 <!--=====================================================================-->
215 <p>
216
217 Compiling LLVM requires that you have several software packages installed:
218
219 <ul compact>
220 <li>
221 <a href="http://gcc.gnu.org">GCC 3.x with C and C++ language support</a>
222
223 <li>
224 <a href="http://savannah.gnu.org/projects/make">GNU Make</a>
225
226 <li>
227 <a href="http://www.gnu.org/software/flex">Flex</a>
228
229 <li>
230 <a href="http://www.gnu.org/software/bison/bison.html">Bison</a>
231 </ul>
232
233 <p>
234 There are some additional tools that you may want to have when working with
235 LLVM:
236 </p>
237
238 <ul>
239 <li><A href="http://www.gnu.org/software/autoconf">GNU Autoconf</A>
240 <li><A href="http://savannah.gnu.org/projects/m4">GNU M4</A>
241 <p>
242 If you want to make changes to the configure scripts, you will need
243 GNU autoconf (2.57 or higher), and consequently, GNU M4 (version 1.4
244 or higher).
245 </p>
246
247 <li><A href="http://www.codesourcery.com/qm/qmtest">QMTest</A>
248 <li><A href="http://www.python.org">Python</A>
249 <p>
250 These are needed to use the LLVM test suite.
251 </ul>
252
253
254 <p>The remainder of this guide is meant to get you up and running with
255 LLVM and to give you some basic information about the LLVM environment.
256 A <a href="#starting">complete guide to installation</a> is provided in the
257 next section.
258
259 <p>The later sections of this guide describe the <a
260 href="#layout">general layout</a> of the the LLVM source tree, a <a
261 href="#tutorial">simple example</a> using the LLVM tool chain, and <a
262 href="#links">links</a> to find more information about LLVM or to get
263 help via e-mail.
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]264
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]265 <!--=====================================================================-->
266 <center>
267 <h2><a name="starting"><b>Getting Started with LLVM</b></a></h2>
268 </center>
269 <hr>
270 <!--=====================================================================-->
271
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]272 <!------------------------------------------------------------------------->
273 <h3><a name="terminology">Terminology and Notation</a></h3>
274 <!------------------------------------------------------------------------->
275
276 <p>Throughout this manual, the following names are used to denote paths
277 specific to the local system and working environment. <i>These are not
John Criswell7a73b802003-06-30 21:59:07 +0000[diff] [blame]278 environment variables you need to set but just strings used in the rest
279 of this document below</i>. In any of the examples below, simply replace
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]280 each of these names with the appropriate pathname on your local system.
Chris Lattner1db872d2002-09-06 16:26:13 +0000[diff] [blame]281 All these paths are absolute:</p>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]282 <dl compact>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]283 <dt>SRC_ROOT
284 <dd>
285 This is the top level directory of the LLVM source tree.
286 <p>
287
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]288 <dt>OBJ_ROOT
289 <dd>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]290 This is the top level directory of the LLVM object tree (i.e. the
291 tree where object files and compiled programs will be placed. It
292 can be the same as SRC_ROOT).
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]293 <p>
294
295 <dt>LLVMGCCDIR
296 <dd>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]297 This is the where the LLVM GCC Front End is installed.
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]298 <p>
John Criswellabb1b582003-10-10 16:17:19 +0000[diff] [blame]299 For the pre-built GCC front end binaries, the LLVMGCCDIR is
John Criswella27028b2003-07-03 16:49:40 +0000[diff] [blame]300 <tt>cfrontend/<i>platform</i>/llvm-gcc</tt>.
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]301 </dl>
302
303 <!------------------------------------------------------------------------->
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]304 <h3><a name="environment">Setting Up Your Environment</a></h3>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]305 <!------------------------------------------------------------------------->
306
307 <p>
308 In order to compile and use LLVM, you will need to set some environment
309 variables. There are also some shell aliases which you may find useful.
310 You can set these on the command line, or better yet, set them in your
311 <tt>.cshrc</tt> or <tt>.profile</tt>.
312
313 <dl compact>
314 <dt><tt>LLVM_LIB_SEARCH_PATH</tt>=<tt><i>LLVMGCCDIR</i>/llvm-gcc/bytecode-libs</tt>
315 <dd>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]316 This environment variable helps the LLVM GCC front end find bytecode
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]317 libraries that it will need for compilation.
318 <p>
319
John Criswellabb1b582003-10-10 16:17:19 +0000[diff] [blame]320 <dt>alias llvmgcc <i>LLVMGCCDIR</i><tt>/llvm-gcc/bin/gcc</tt>
321 <dt>alias llvmg++ <i>LLVMGCCDIR</i><tt>/llvm-gcc/bin/g++</tt>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]322 <dd>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]323 This alias allows you to use the LLVM C and C++ front ends without putting
324 them in your <tt>PATH</tt> or typing in their complete pathnames.
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]325 </dl>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]326
327 <!------------------------------------------------------------------------->
John Criswell312a68c2003-07-07 19:27:35 +0000[diff] [blame]328 <h3><a name="unpack">Unpacking the LLVM Archives</a></h3>
329 <!------------------------------------------------------------------------->
330
331 <p>
332 If you have the LLVM distribution, you will need to unpack it before you
John Criswellabb1b582003-10-10 16:17:19 +0000[diff] [blame]333 can begin to compile it. LLVM is distributed as a set of three files. Each
John Criswell312a68c2003-07-07 19:27:35 +0000[diff] [blame]334 file is a TAR archive that is compressed with the gzip program.
335 </p>
336
John Criswellabb1b582003-10-10 16:17:19 +0000[diff] [blame]337 <p> The three files are as follows:
John Criswell312a68c2003-07-07 19:27:35 +0000[diff] [blame]338 <dl compact>
339 <dt>llvm.tar.gz
340 <dd>This is the source code to the LLVM suite.
341 <p>
342
343 <dt>cfrontend.sparc.tar.gz
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]344 <dd>This is the binary release of the GCC front end for Solaris/Sparc.
John Criswell312a68c2003-07-07 19:27:35 +0000[diff] [blame]345 <p>
346
347 <dt>cfrontend.x86.tar.gz
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]348 <dd>This is the binary release of the GCC front end for Linux/x86.
John Criswell312a68c2003-07-07 19:27:35 +0000[diff] [blame]349 </dl>
350
John Criswell312a68c2003-07-07 19:27:35 +0000[diff] [blame]351 <!------------------------------------------------------------------------->
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]352 <h3><a name="checkout">Checkout LLVM from CVS</a></h3>
353 <!------------------------------------------------------------------------->
354
John Criswell312a68c2003-07-07 19:27:35 +0000[diff] [blame]355 <p>If you have access to our CVS repository, you can get a fresh copy of
356 the entire source code. All you need to do is check it out from CVS as
357 follows:
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]358 <ul>
359 <li><tt>cd <i>where-you-want-llvm-to-live</i></tt>
John Criswelle04c2632003-10-21 21:24:38 +0000[diff] [blame]360 <li><tt>cvs -d :pserver:anon@llvm-cvs.cs.uiuc.edu:/var/cvs/llvm login</tt>
361 <li>Hit the return key when prompted for the password.
Chris Lattner70bb09b2003-10-23 19:49:01 +0000[diff] [blame]362 <li><tt>cvs -z3 -d :pserver:anon@llvm-cvs.cs.uiuc.edu:/var/cvs/llvm co llvm</tt>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]363 </ul>
364
365 <p>This will create an '<tt>llvm</tt>' directory in the current
366 directory and fully populate it with the LLVM source code, Makefiles,
367 test directories, and local copies of documentation files.</p>
368
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]369 <p>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]370 Note that the GCC front end is not included in the CVS repository. You
John Criswellabb1b582003-10-10 16:17:19 +0000[diff] [blame]371 should have downloaded the binary distribution for your platform.
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]372 </p>
373
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]374 <!------------------------------------------------------------------------->
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]375 <h3><a name="installcf">Install the GCC Front End</a></h3>
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]376 <!------------------------------------------------------------------------->
377
378 <p>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]379 Before configuring and compiling the LLVM suite, you need to extract the
380 LLVM GCC front end from the binary distribution. It is used for building the
381 bytecode libraries later used by the GCC front end for linking programs, and
382 its location must be specified when the LLVM suite is configured.
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]383 </p>
384
385 <p>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]386 To install the GCC front end, do the following:
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]387 <ol>
388 <li><tt>cd <i>where-you-want-the-front-end-to-live</i></tt>
389 <li><tt>gunzip --stdout cfrontend.<i>platform</i>.tar.gz | tar -xvf
390 -</tt>
391 </ol>
392
393 <!------------------------------------------------------------------------->
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]394 <h3><a name="config">Local LLVM Configuration</a></h3>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]395 <!------------------------------------------------------------------------->
396
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]397 <p>Once checked out from the CVS repository, the LLVM suite source code
398 must be configured via the <tt>configure</tt> script. This script sets
399 variables in <tt>llvm/Makefile.config</tt> and
John Criswelle04c2632003-10-21 21:24:38 +0000[diff] [blame]400 <tt>llvm/include/Config/config.h</tt>. It also populates <i>OBJ_ROOT</i>
401 with the Makefiles needed to build LLVM.
John Criswell7a73b802003-06-30 21:59:07 +0000[diff] [blame]402
403 <p>
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]404 The following environment variables are used by the <tt>configure</tt>
405 script to configure the build system:
John Criswell7a73b802003-06-30 21:59:07 +0000[diff] [blame]406 </p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]407
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]408 <table border=1>
409 <tr>
410 <th>Variable</th>
411 <th>
412 Purpose
413 </th>
414 </tr>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]415
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]416 <tr>
417 <td>CC</td>
418 <td>
419 Tells <tt>configure</tt> which C compiler to use. By default,
John Criswellabb1b582003-10-10 16:17:19 +0000[diff] [blame]420 <tt>configure</tt> will look for the first GCC C compiler in
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]421 <tt>PATH</tt>. Use this variable to override
422 <tt>configure</tt>'s default behavior.
423 </td>
424 </tr>
425
426 <tr>
427 <td>CXX</td>
428 <td>
429 Tells <tt>configure</tt> which C++ compiler to use. By default,
John Criswellabb1b582003-10-10 16:17:19 +0000[diff] [blame]430 <tt>configure</tt> will look for the first GCC C++ compiler in
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]431 <tt>PATH</tt>. Use this variable to override
432 <tt>configure</tt>'s default behavior.
433 </td>
434 </tr>
435 </table>
436
437 <p>
John Criswell7a73b802003-06-30 21:59:07 +0000[diff] [blame]438 The following options can be used to set or enable LLVM specific options:
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]439 </p>
John Criswell7a73b802003-06-30 21:59:07 +0000[diff] [blame]440
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]441 <dl compact>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]442 <dt><i>--with-llvmgccdir=LLVMGCCDIR</i>
443 <dd>
444 Path to the location where the LLVM C front end binaries and
445 associated libraries will be installed.
446 <p>
447 <dt><i>--enable-optimized</i>
448 <dd>
John Criswell623e5942003-10-10 18:51:11 +0000[diff] [blame]449 Enables optimized compilation by default (debugging symbols are removed
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]450 and GCC optimization flags are enabled). The default is to use an
451 unoptimized build (also known as a debug build).
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]452 <p>
453 <dt><i>--enable-jit</i>
454 <dd>
John Criswell7a73b802003-06-30 21:59:07 +0000[diff] [blame]455 Compile the Just In Time (JIT) functionality. This is not available
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]456 on all platforms. The default is dependent on platform, so it is best
457 to explicitly enable it if you want it.
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]458 <p>
459 <dt><i>--enable-spec2000</i>
460 <dt><i>--enable-spec2000=&lt;<tt>directory</tt>&gt;</i>
461 <dd>
462 Enable the use of SPEC2000 when testing LLVM. This is disabled by default
John Criswellabb1b582003-10-10 16:17:19 +0000[diff] [blame]463 (unless <tt>configure</tt> finds SPEC2000 installed). By specifying
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]464 <tt>directory</tt>, you can tell configure where to find the SPEC2000
John Criswellabb1b582003-10-10 16:17:19 +0000[diff] [blame]465 benchmarks. If <tt>directory</tt> is left unspecified, <tt>configure</tt>
466 uses the default value
467 <tt>/home/vadve/shared/benchmarks/speccpu2000/benchspec</tt>.
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]468 </dl>
John Criswell7a73b802003-06-30 21:59:07 +0000[diff] [blame]469
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]470 <p>
471 To configure LLVM, follow these steps:
472 <ol>
473 <li>Change directory into the object root directory:
474 <br>
475 <tt>cd <i>OBJ_ROOT</i></tt>
476 <p>
477
John Criswellabb1b582003-10-10 16:17:19 +0000[diff] [blame]478 <li>Run the <tt>configure</tt> script located in the LLVM source tree:
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]479 <br>
480 <tt><i>SRC_ROOT</i>/configure</tt>
481 <p>
482 </ol>
483 </p>
484
John Criswell7a73b802003-06-30 21:59:07 +0000[diff] [blame]485 In addition to running <tt>configure</tt>, you must set the
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]486 <tt>LLVM_LIB_SEARCH_PATH</tt> environment variable in your startup scripts.
487 This environment variable is used to locate "system" libraries like
488 "<tt>-lc</tt>" and "<tt>-lm</tt>" when linking. This variable should be set
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]489 to the absolute path for the bytecode-libs subdirectory of the GCC front end
John Criswellabb1b582003-10-10 16:17:19 +0000[diff] [blame]490 install, or <i>LLVMGCCDIR</i>/llvm-gcc/bytecode-libs. For example, one might
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]491 set <tt>LLVM_LIB_SEARCH_PATH</tt> to
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]492 <tt>/home/vadve/lattner/local/x86/llvm-gcc/bytecode-libs</tt> for the X86
John Criswellabb1b582003-10-10 16:17:19 +0000[diff] [blame]493 version of the GCC front end on our research machines.<p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]494
495 <!------------------------------------------------------------------------->
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]496 <h3><a name="compile">Compiling the LLVM Suite Source Code</a></h3>
497 <!------------------------------------------------------------------------->
498
499 Once you have configured LLVM, you can build it. There are three types of
500 builds:
501
502 <dl compact>
503 <dt>Debug Builds
504 <dd>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]505 These builds are the default when one types <tt>gmake</tt> (unless the
John Criswellabb1b582003-10-10 16:17:19 +0000[diff] [blame]506 <tt>--enable-optimized</tt> option was used during configuration). The
507 build system will compile the tools and libraries with debugging
508 information.
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]509 <p>
510
511 <dt>Release (Optimized) Builds
512 <dd>
513 These builds are enabled with the <tt>--enable-optimized</tt> option to
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]514 <tt>configure</tt> or by specifying <tt>ENABLE_OPTIMIZED=1</tt> on the
John Criswellabb1b582003-10-10 16:17:19 +0000[diff] [blame]515 <tt>gmake</tt> command line. For these builds, the build system will
516 compile the tools and libraries with GCC optimizations enabled and strip
517 debugging information from the libraries and executables it generates.
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]518 <p>
519
520 <dt>Profile Builds
521 <dd>
522 These builds are for use with profiling. They compile profiling
523 information into the code for use with programs like <tt>gprof</tt>.
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]524 Profile builds must be started by specifying <tt>ENABLE_PROFILING=1</tt>
525 on the <tt>gmake</tt> command line.
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]526 </dl>
527
John Criswellabb1b582003-10-10 16:17:19 +0000[diff] [blame]528 Once you have LLVM configured, you can build it by entering the
529 <i>OBJ_ROOT</i> directory and issuing the following command:
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]530 <p>
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]531 <tt>gmake</tt>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]532
533 <p>
534 If you have multiple processors in your machine, you may wish to use some
535 of the parallel build options provided by GNU Make. For example, you could
536 use the command:
537 </p>
538
539 <p>
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]540 <tt>gmake -j2</tt>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]541
542 <p>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]543 There are several special targets which are useful when working with the LLVM
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]544 source code:
545
546 <dl compact>
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]547 <dt><tt>gmake clean</tt>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]548 <dd>
549 Removes all files generated by the build. This includes object files,
550 generated C/C++ files, libraries, and executables.
551 <p>
552
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]553 <dt><tt>gmake distclean</tt>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]554 <dd>
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]555 Removes everything that <tt>gmake clean</tt> does, but also removes
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]556 files generated by <tt>configure</tt>. It attempts to return the
557 source tree to the original state in which it was shipped.
558 <p>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]559
560 <dt><tt>gmake install</tt>
561 <dd>
562 Installs LLVM files into the proper location. For the most part,
563 this does nothing, but it does install bytecode libraries into the
564 GCC front end's bytecode library directory. If you need to update
565 your bytecode libraries, this is the target to use once you've built
566 them.
567 <p>
568
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]569 </dl>
570
571 It is also possible to override default values from <tt>configure</tt> by
572 declaring variables on the command line. The following are some examples:
573
574 <dl compact>
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]575 <dt><tt>gmake ENABLE_OPTIMIZED=1</tt>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]576 <dd>
577 Perform a Release (Optimized) build.
578 <p>
579
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]580 <dt><tt>gmake ENABLE_PROFILING=1</tt>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]581 <dd>
582 Perform a Profiling build.
583 <p>
584
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]585 <dt><tt>gmake VERBOSE=1</tt>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]586 <dd>
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]587 Print what <tt>gmake</tt> is doing on standard output.
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]588 <p>
589 </dl>
590
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]591 Every directory in the LLVM object tree includes a <tt>Makefile</tt> to
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]592 build it and any subdirectories that it contains. Entering any directory
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]593 inside the LLVM object tree and typing <tt>gmake</tt> should rebuild
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]594 anything in or below that directory that is out of date.
595
596 <!------------------------------------------------------------------------->
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]597 <h3><a name="objfiles">The Location of LLVM Object Files</a></h3>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]598 <!------------------------------------------------------------------------->
599
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]600 <p>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]601 The LLVM build system is capable of sharing a single LLVM source tree among
602 several LLVM builds. Hence, it is possible to build LLVM for several
603 different platforms or configurations using the same source tree.
John Criswellef0096f2003-08-08 22:36:30 +0000[diff] [blame]604 <p>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]605 This is accomplished in the typical autoconf manner:
606 <ul>
607 <li>Change directory to where the LLVM object files should live:
608 <p>
609 <tt>cd <i>OBJ_ROOT</i></tt>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]610
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]611 <li>Run the <tt>configure</tt> script found in the LLVM source directory:
612 <p>
613 <tt><i>SRC_ROOT</i>/configure</tt>
614 </ul>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]615
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]616 <p>
617 The LLVM build will place files underneath <i>OBJ_ROOT</i> in directories
618 named after the build type:
619 </p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]620
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]621 <dl compact>
622 <dt>Debug Builds
623 <dd>
624 <dl compact>
625 <dt>Tools
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]626 <dd><tt><i>OBJ_ROOT</i>/tools/Debug</tt>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]627 <dt>Libraries
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]628 <dd><tt><i>OBJ_ROOT</i>/lib/Debug</tt>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]629 </dl>
630 <p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]631
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]632 <dt>Release Builds
633 <dd>
634 <dl compact>
635 <dt>Tools
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]636 <dd><tt><i>OBJ_ROOT</i>/tools/Release</tt>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]637 <dt>Libraries
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]638 <dd><tt><i>OBJ_ROOT</i>/lib/Release</tt>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]639 </dl>
640 <p>
Chris Lattner7fe7f812002-07-24 19:51:14 +0000[diff] [blame]641
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]642 <dt>Profile Builds
643 <dd>
644 <dl compact>
645 <dt>Tools
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]646 <dd><tt><i>OBJ_ROOT</i>/tools/Profile</tt>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]647 <dt>Libraries
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]648 <dd><tt><i>OBJ_ROOT</i>/lib/Profile</tt>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]649 </dl>
650 </dl>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]651
652 <!--=====================================================================-->
653 <center>
654 <h2><a name="layout"><b>Program Layout</b></a></h2>
655 </center>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]656 <hr>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]657 <!--=====================================================================-->
658
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]659 <p>
660 One useful source of information about the LLVM source base is the LLVM <a
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]661 href="http://www.doxygen.org">doxygen</a> documentation, available at <tt><a
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]662 href="http://llvm.cs.uiuc.edu/doxygen/">http://llvm.cs.uiuc.edu/doxygen/</a></tt>.
663 The following is a brief introduction to code layout:
664 </p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]665
666 <!------------------------------------------------------------------------->
667 <h3><a name="cvsdir"><tt>CVS</tt> directories</a></h3>
668 <!------------------------------------------------------------------------->
669
670 Every directory checked out of CVS will contain a <tt>CVS</tt> directory;
671 for the most part these can just be ignored.
672
673
674 <!------------------------------------------------------------------------->
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]675 <h3><a name="include"><tt>llvm/include</tt></a></h3>
676 <!------------------------------------------------------------------------->
677
678 This directory contains public header files exported from the LLVM
John Criswell7a73b802003-06-30 21:59:07 +0000[diff] [blame]679 library. The three main subdirectories of this directory are:<p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]680
John Criswell8df90e02003-06-11 20:46:40 +0000[diff] [blame]681 <ol>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]682 <li><tt>llvm/include/llvm</tt> - This directory contains all of the LLVM
683 specific header files. This directory also has subdirectories for
684 different portions of LLVM: <tt>Analysis</tt>, <tt>CodeGen</tt>,
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]685 <tt>Target</tt>, <tt>Transforms</tt>, etc...
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]686
687 <li><tt>llvm/include/Support</tt> - This directory contains generic
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]688 support libraries that are independent of LLVM, but are used by LLVM.
John Criswell7a73b802003-06-30 21:59:07 +0000[diff] [blame]689 For example, some C++ STL utilities and a Command Line option processing
John Criswellabb1b582003-10-10 16:17:19 +0000[diff] [blame]690 library store their header files here.
John Criswell7a73b802003-06-30 21:59:07 +0000[diff] [blame]691
692 <li><tt>llvm/include/Config</tt> - This directory contains header files
693 configured by the <tt>configure</tt> script. They wrap "standard" UNIX
694 and C header files. Source code can include these header files which
John Criswellabb1b582003-10-10 16:17:19 +0000[diff] [blame]695 automatically take care of the conditional #includes that the
696 <tt>configure</tt> script generates.
Chris Lattner7fe7f812002-07-24 19:51:14 +0000[diff] [blame]697 </ol>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]698
699 <!------------------------------------------------------------------------->
700 <h3><a name="lib"><tt>llvm/lib</tt></a></h3>
701 <!------------------------------------------------------------------------->
702
John Criswell7a73b802003-06-30 21:59:07 +0000[diff] [blame]703 This directory contains most of the source files of the LLVM system. In
John Criswellabb1b582003-10-10 16:17:19 +0000[diff] [blame]704 LLVM, almost all
John Criswell7a73b802003-06-30 21:59:07 +0000[diff] [blame]705 code exists in libraries, making it very easy to share code among the
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]706 different <a href="#tools">tools</a>.<p>
707
708 <dl compact>
709 <dt><tt>llvm/lib/VMCore/</tt><dd> This directory holds the core LLVM
710 source files that implement core classes like Instruction and BasicBlock.
711
712 <dt><tt>llvm/lib/AsmParser/</tt><dd> This directory holds the source code
713 for the LLVM assembly language parser library.
714
715 <dt><tt>llvm/lib/ByteCode/</tt><dd> This directory holds code for reading
716 and write LLVM bytecode.
717
718 <dt><tt>llvm/lib/CWriter/</tt><dd> This directory implements the LLVM to C
719 converter.
720
721 <dt><tt>llvm/lib/Analysis/</tt><dd> This directory contains a variety of
722 different program analyses, such as Dominator Information, Call Graphs,
723 Induction Variables, Interval Identification, Natural Loop Identification,
724 etc...
725
726 <dt><tt>llvm/lib/Transforms/</tt><dd> This directory contains the source
727 code for the LLVM to LLVM program transformations, such as Aggressive Dead
728 Code Elimination, Sparse Conditional Constant Propagation, Inlining, Loop
John Criswell623e5942003-10-10 18:51:11 +0000[diff] [blame]729 Invariant Code Motion, Dead Global Elimination, and many others...
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]730
731 <dt><tt>llvm/lib/Target/</tt><dd> This directory contains files that
732 describe various target architectures for code generation. For example,
733 the llvm/lib/Target/Sparc directory holds the Sparc machine
734 description.<br>
735
736 <dt><tt>llvm/lib/CodeGen/</tt><dd> This directory contains the major parts
737 of the code generator: Instruction Selector, Instruction Scheduling, and
738 Register Allocation.
739
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]740 <dt><tt>llvm/lib/Support/</tt><dd> This directory contains the source code
741 that corresponds to the header files located in
742 <tt>llvm/include/Support/</tt>.
743 </dl>
744
745 <!------------------------------------------------------------------------->
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]746 <h3><a name="runtime"><tt>llvm/runtime</tt></a></h3>
747 <!------------------------------------------------------------------------->
748
749 <p>
750 This directory contains libraries which are compiled into LLVM bytecode and
751 used when linking programs with the GCC front end. Most of these libraries
752 are skeleton versions of real libraries; for example, libc is a stripped down
753 version of glibc.
754 </p>
755
756 <p>
757 Unlike the rest of the LLVM suite, this directory needs the LLVM GCC front end
758 to compile.
759 </p>
760
761 <!------------------------------------------------------------------------->
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]762 <h3><a name="test"><tt>llvm/test</tt></a></h3>
763 <!------------------------------------------------------------------------->
764
765 <p>This directory contains regression tests and source code that is used to
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]766 test the LLVM infrastructure.
767 </p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]768
769 <!------------------------------------------------------------------------->
770 <h3><a name="tools"><tt>llvm/tools</tt></a></h3>
771 <!------------------------------------------------------------------------->
772
773 <p>The <b>tools</b> directory contains the executables built out of the
774 libraries above, which form the main part of the user interface. You can
775 always get help for a tool by typing <tt>tool_name --help</tt>. The
776 following is a brief introduction to the most important tools.</p>
777
778 <dl compact>
Misha Brukmanef0ad412003-10-06 19:23:34 +0000[diff] [blame]779 <dt>
780
781 <dt><tt><b>analyze</b></tt><dd> <tt>analyze</tt> is used to run a specific
782 analysis on an input LLVM bytecode file and print out the results. It is
783 primarily useful for debugging analyses, or familiarizing yourself with
784 what an analysis does.<p>
785
786 <dt><tt><b>bugpoint</b></tt><dd> <tt>bugpoint</tt> is used to debug
787 optimization passes or code generation backends by narrowing down the
788 given test case to the minimum number of passes and/or instructions that
789 still cause a problem, whether it is a crash or miscompilation. See <a
790 href="HowToSubmitABug.html">HowToSubmitABug.html</a> for more information
791 on using <tt>bugpoint</tt>.<p>
792
793 <dt><tt><b>llvm-ar</b></tt><dd>The archiver produces an archive containing
794 the given LLVM bytecode files, optionally with an index for faster
795 lookup.<p>
796
Misha Brukmana0a0a032003-08-28 22:02:50 +0000[diff] [blame]797 <dt><tt><b>llvm-as</b></tt><dd>The assembler transforms the human readable
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]798 LLVM assembly to LLVM bytecode.<p>
799
Misha Brukmana0a0a032003-08-28 22:02:50 +0000[diff] [blame]800 <dt><tt><b>llvm-dis</b></tt><dd>The disassembler transforms the LLVM
Misha Brukmanef0ad412003-10-06 19:23:34 +0000[diff] [blame]801 bytecode to human readable LLVM assembly. Additionally, it can convert
Misha Brukmana0a0a032003-08-28 22:02:50 +0000[diff] [blame]802 LLVM bytecode to C, which is enabled with the <tt>-c</tt> option.<p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]803
Misha Brukmanef0ad412003-10-06 19:23:34 +0000[diff] [blame]804 <dt><tt><b>llvm-link</b></tt><dd> <tt>llvm-link</tt>, not surprisingly,
805 links multiple LLVM modules into a single program.<p>
806
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]807 <dt><tt><b>lli</b></tt><dd> <tt>lli</tt> is the LLVM interpreter, which
808 can directly execute LLVM bytecode (although very slowly...). In addition
Misha Brukmanef0ad412003-10-06 19:23:34 +0000[diff] [blame]809 to a simple interpreter, <tt>lli</tt> also has a tracing mode (entered by
810 specifying <tt>-trace</tt> on the command line). Finally, for
811 architectures that support it (currently only x86 and Sparc), by default,
812 <tt>lli</tt> will function as a Just-In-Time compiler (if the
813 functionality was compiled in), and will execute the code <i>much</i>
814 faster than the interpreter.<p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]815
816 <dt><tt><b>llc</b></tt><dd> <tt>llc</tt> is the LLVM backend compiler,
Misha Brukmanc56e5822003-07-03 16:29:36 +0000[diff] [blame]817 which translates LLVM bytecode to a SPARC or x86 assembly file.<p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]818
Misha Brukmanef0ad412003-10-06 19:23:34 +0000[diff] [blame]819 <dt><tt><b>llvmgcc</b></tt><dd> <tt>llvmgcc</tt> is a GCC-based C frontend
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]820 that has been retargeted to emit LLVM code as the machine code output. It
821 works just like any other GCC compiler, taking the typical <tt>-c, -S, -E,
822 -o</tt> options that are typically used. The source code for the
Chris Lattner70bb09b2003-10-23 19:49:01 +0000[diff] [blame]823 <tt>llvmgcc</tt> tool is currently not included in the LLVM CVS tree
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]824 because it is quite large and not very interesting.<p>
825
826 <ol>
827 <dt><tt><b>gccas</b></tt><dd> This tool is invoked by the
828 <tt>llvmgcc</tt> frontend as the "assembler" part of the compiler. This
829 tool actually assembles LLVM assembly to LLVM bytecode,
Misha Brukmanef0ad412003-10-06 19:23:34 +0000[diff] [blame]830 performs a variety of optimizations, and outputs LLVM bytecode. Thus
831 when you invoke <tt>llvmgcc -c x.c -o x.o</tt>, you are causing
832 <tt>gccas</tt> to be run, which writes the <tt>x.o</tt> file (which is
833 an LLVM bytecode file that can be disassembled or manipulated just like
834 any other bytecode file). The command line interface to <tt>gccas</tt>
835 is designed to be as close as possible to the <b>system</b>
836 `<tt>as</tt>' utility so that the gcc frontend itself did not have to be
837 modified to interface to a "weird" assembler.<p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]838
839 <dt><tt><b>gccld</b></tt><dd> <tt>gccld</tt> links together several LLVM
840 bytecode files into one bytecode file and does some optimization. It is
John Criswellabb1b582003-10-10 16:17:19 +0000[diff] [blame]841 the linker invoked by the GCC frontend when multiple .o files need to be
842 linked together. Like <tt>gccas</tt>, the command line interface of
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]843 <tt>gccld</tt> is designed to match the system linker, to aid
844 interfacing with the GCC frontend.<p>
845 </ol>
846
847 <dt><tt><b>opt</b></tt><dd> <tt>opt</tt> reads LLVM bytecode, applies a
848 series of LLVM to LLVM transformations (which are specified on the command
849 line), and then outputs the resultant bytecode. The '<tt>opt --help</tt>'
850 command is a good way to get a list of the program transformations
851 available in LLVM.<p>
852
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]853 </dl>
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]854
Misha Brukmanc103adf2003-08-11 18:45:46 +0000[diff] [blame]855 <!------------------------------------------------------------------------->
856 <h3><a name="utils"><tt>llvm/utils</tt></a></h3>
857 <!------------------------------------------------------------------------->
858
John Criswell623e5942003-10-10 18:51:11 +0000[diff] [blame]859 This directory contains utilities for working with LLVM source code, and some
Misha Brukmanc103adf2003-08-11 18:45:46 +0000[diff] [blame]860 of the utilities are actually required as part of the build process because
861 they are code generators for parts of LLVM infrastructure.
862
863 <dl compact>
Misha Brukmane0db8152003-08-11 19:13:12 +0000[diff] [blame]864 <td><tt><b>Burg/</b></tt><dd> <tt>Burg</tt> is an instruction selector
Misha Brukmanc103adf2003-08-11 18:45:46 +0000[diff] [blame]865 generator -- it builds trees on which it then performs pattern-matching to
866 select instructions according to the patterns the user has specified. Burg
867 is currently used in the Sparc V9 backend.<p>
868
869 <dt><tt><b>codegen-diff</b></tt><dd> <tt>codegen-diff</tt> is a script
870 that finds differences between code that LLC generates and code that LLI
871 generates. This is a useful tool if you are debugging one of them,
872 assuming that the other generates correct output. For the full user
873 manual, run <tt>`perldoc codegen-diff'</tt>.<p>
874
875 <dt><tt><b>cvsupdate</b></tt><dd> <tt>cvsupdate</tt> is a script that will
876 update your CVS tree, but produce a much cleaner and more organized output
Chris Lattner70bb09b2003-10-23 19:49:01 +0000[diff] [blame]877 than simply running <tt>`cvs -z3 up -dP'</tt> will. For example, it will group
Misha Brukmanc103adf2003-08-11 18:45:46 +0000[diff] [blame]878 together all the new and updated files and modified files in separate
879 sections, so you can see at a glance what has changed. If you are at the
880 top of your LLVM CVS tree, running <tt>utils/cvsupdate</tt> is the
881 preferred way of updating the tree.<p>
882
Misha Brukmane0db8152003-08-11 19:13:12 +0000[diff] [blame]883 <dt><tt><b>emacs/</b></tt><dd> The <tt>emacs</tt> directory contains
Misha Brukmanc103adf2003-08-11 18:45:46 +0000[diff] [blame]884 syntax-highlighting files which will work with Emacs and XEmacs editors,
885 providing syntax highlighting support for LLVM assembly files and TableGen
Misha Brukmane0db8152003-08-11 19:13:12 +0000[diff] [blame]886 description files. For information on how to use the syntax files, consult
887 the <tt>README</tt> file in that directory.<p>
Misha Brukmanc103adf2003-08-11 18:45:46 +0000[diff] [blame]888
889 <dt><tt><b>getsrcs.sh</b></tt><dd> The <tt>getsrcs.sh</tt> script finds
890 and outputs all non-generated source files, which is useful if one wishes
891 to do a lot of development across directories and does not want to
892 individually find each file. One way to use it is to run, for example:
893 <tt>xemacs `utils/getsources.sh`</tt> from the top of your LLVM source
894 tree.<p>
895
896 <dt><tt><b>makellvm</b></tt><dd> The <tt>makellvm</tt> script compiles all
897 files in the current directory and then compiles and links the tool that
898 is the first argument. For example, assuming you are in the directory
899 <tt>llvm/lib/Target/Sparc</tt>, if <tt>makellvm</tt> is in your path,
900 simply running <tt>makellvm llc</tt> will make a build of the current
901 directory, switch to directory <tt>llvm/tools/llc</tt> and build it,
902 causing a re-linking of LLC.<p>
903
904 <dt><tt><b>NightlyTest.pl</b></tt> and
905 <tt><b>NightlyTestTemplate.html</b></tt><dd> These files are used in a
906 cron script to generate nightly status reports of the functionality of
907 tools, and the results can be seen by following the appropriate link on
908 the <a href="http://llvm.cs.uiuc.edu/">LLVM homepage</a>.<p>
909
Misha Brukmane0db8152003-08-11 19:13:12 +0000[diff] [blame]910 <dt><tt><b>TableGen/</b></tt><dd> The <tt>TableGen</tt> directory contains
Misha Brukmanc103adf2003-08-11 18:45:46 +0000[diff] [blame]911 the tool used to generate register descriptions, instruction set
Chris Lattnera8f5de32003-08-11 18:53:14 +0000[diff] [blame]912 descriptions, and even assemblers from common TableGen description
Misha Brukmanc103adf2003-08-11 18:45:46 +0000[diff] [blame]913 files.<p>
914
Misha Brukmane0db8152003-08-11 19:13:12 +0000[diff] [blame]915 <dt><tt><b>vim/</b></tt><dd> The <tt>vim</tt> directory contains
Misha Brukmanc103adf2003-08-11 18:45:46 +0000[diff] [blame]916 syntax-highlighting files which will work with the VIM editor, providing
917 syntax highlighting support for LLVM assembly files and TableGen
Misha Brukmane0db8152003-08-11 19:13:12 +0000[diff] [blame]918 description files. For information on how to use the syntax files, consult
919 the <tt>README</tt> file in that directory.<p>
Misha Brukmanc103adf2003-08-11 18:45:46 +0000[diff] [blame]920
921 </dl>
922
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]923 <!--=====================================================================-->
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]924 <h2>
925 <center><a name="tutorial">An Example Using the LLVM Tool Chain</center>
926 </h2>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]927 <hr>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]928 <!--=====================================================================-->
929
930 <ol>
931 <li>First, create a simple C file, name it 'hello.c':
932 <pre>
933 #include &lt;stdio.h&gt;
934 int main() {
935 printf("hello world\n");
936 return 0;
937 }
938 </pre>
939
940 <li>Next, compile the C file into a LLVM bytecode file:<p>
941
942 <tt>% llvmgcc hello.c -o hello</tt><p>
943
944 This will create two result files: <tt>hello</tt> and
945 <tt>hello.bc</tt>. The <tt>hello.bc</tt> is the LLVM bytecode that
946 corresponds the the compiled program and the library facilities that it
947 required. <tt>hello</tt> is a simple shell script that runs the bytecode
948 file with <tt>lli</tt>, making the result directly executable.<p>
949
950 <li>Run the program. To make sure the program ran, execute one of the
951 following commands:<p>
John Criswell8df90e02003-06-11 20:46:40 +0000[diff] [blame]952
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]953 <tt>% ./hello</tt><p>
954
955 or<p>
956
957 <tt>% lli hello.bc</tt><p>
958
Misha Brukmana0a0a032003-08-28 22:02:50 +0000[diff] [blame]959 <li>Use the <tt>llvm-dis</tt> utility to take a look at the LLVM assembly
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]960 code:<p>
961
Misha Brukmana0a0a032003-08-28 22:02:50 +0000[diff] [blame]962 <tt>% llvm-dis < hello.bc | less</tt><p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]963
964 <li>Compile the program to native Sparc assembly using the code
Misha Brukmanc56e5822003-07-03 16:29:36 +0000[diff] [blame]965 generator (assuming you are currently on a Sparc system):<p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]966
967 <tt>% llc hello.bc -o hello.s</tt><p>
968
969 <li>Assemble the native sparc assemble file into a program:<p>
970
971 <tt>% /opt/SUNWspro/bin/cc -xarch=v9 hello.s -o hello.sparc</tt><p>
972
973 <li>Execute the native sparc program:<p>
974
975 <tt>% ./hello.sparc</tt><p>
976
977 </ol>
978
979
980 <!--=====================================================================-->
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]981 <h2>
982 <center><a name="problems">Common Problems</a></center>
983 </h2>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]984 <hr>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]985 <!--=====================================================================-->
986
John Criswellb96646f2003-10-13 16:16:25 +0000[diff] [blame]987 If you are having problems building or using LLVM, or if you have any other
988 general questions about LLVM, please consult the
John Criswellb5ca43e2003-10-13 16:19:30 +0000[diff] [blame]989 <a href="FAQ.html">Frequently Asked Questions</a> page.
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]990
991 <!--=====================================================================-->
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]992 <h2><center><a name="links">Links</a></center></h2>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]993 <hr>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]994 <!--=====================================================================-->
995
996 <p>This document is just an <b>introduction</b> to how to use LLVM to do
997 some simple things... there are many more interesting and complicated things
998 that you can do that aren't documented here (but we'll gladly accept a patch
999 if you want to write something up!). For more information about LLVM, check
1000 out:</p>
1001
1002 <ul>
1003 <li><a href="http://llvm.cs.uiuc.edu/">LLVM homepage</a></li>
1004 <li><a href="http://llvm.cs.uiuc.edu/doxygen/">LLVM doxygen tree</a></li>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]1005 <li><a href="http://llvm.cs.uiuc.edu/docs/Projects.html">Starting a Project that Uses LLVM</a></li>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]1006 </ul>
1007
1008 <hr>
1009
1010 If you have any questions or run into any snags (or you have any
1011 additions...), please send an email to
1012 <a href="mailto:sabre@nondot.org">Chris Lattner</a>.</p>
1013
1014 <!-- Created: Mon Jul 1 02:29:02 CDT 2002 -->
1015 <!-- hhmts start -->
Chris Lattnera8f5de32003-08-11 18:53:14 +0000[diff] [blame]1016Last modified: Mon Aug 11 13:52:22 CDT 2003
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]1017<!-- hhmts end -->
1018 </body>
Guochun Shif4688a82002-07-17 23:05:56 +0000[diff] [blame]1019</html>