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5 <title>Getting Started with LLVM System</title>
6 <link rel="stylesheet" href="llvm.css" type="text/css">
7</head>
8<body>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]9
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]10<div class="doc_title">
11 Getting Started with the LLVM System
12</div>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]13
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]14<ul>
15 <li><a href="#overview">Overview</a>
16 <li><a href="#quickstart">Getting Started Quickly (A Summary)</a>
17 <li><a href="#requirements">Requirements</a>
Chris Lattner96768ea2003-02-14 04:22:13 +0000[diff] [blame]18 <ol>
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]19 <li><a href="#hardware">Hardware</a>
20 <li><a href="#software">Software</a>
21 </ol></li>
John Criswell7a73b802003-06-30 21:59:07 +0000[diff] [blame]22
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]23 <li><a href="#starting">Getting Started with LLVM</a>
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]24 <ol>
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]25 <li><a href="#terminology">Terminology and Notation</a>
26 <li><a href="#environment">Setting Up Your Environment</a>
27 <li><a href="#unpack">Unpacking the LLVM Archives</a>
28 <li><a href="#checkout">Checkout LLVM from CVS</a>
29 <li><a href="#installcf">Install the GCC Front End</a>
30 <li><a href="#config">Local LLVM Configuration</a>
31 <li><a href="#compile">Compiling the LLVM Suite Source Code</a>
32 <li><a href="#objfiles">The Location of LLVM Object Files</a>
33 </ol></li>
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]34
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]35 <li><a href="#layout">Program layout</a>
36 <ol>
37 <li><a href="#cvsdir"><tt>CVS</tt> directories</a>
38 <li><a href="#include"><tt>llvm/include</tt></a>
39 <li><a href="#lib"><tt>llvm/lib</tt></a>
40 <li><a href="#runtime"><tt>llvm/runtime</tt></a>
41 <li><a href="#test"><tt>llvm/test</tt></a>
42 <li><a href="#tools"><tt>llvm/tools</tt></a>
43 <li><a href="#utils"><tt>llvm/utils</tt></a>
44 </ol></li>
John Criswell0f6d7c02003-10-27 18:18:16 +0000[diff] [blame]45
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]46 <li><a href="#tutorial">An Example Using the LLVM Tool Chain</a>
47 <li><a href="#problems">Common Problems</a>
48 <li><a href="#links">Links</a>
49</ul>
50
51<p>By:
52 <a href="mailto:gshi1@uiuc.edu">Guochun Shi</a>,
53 <a href="mailto:sabre@nondot.org">Chris Lattner</a>,
54 <a href="mailto:criswell@uiuc.edu">John Criswell</a>,
55 <a href="http://misha.brukman.net">Misha Brukman</a>, and
56 <a href="http://www.cs.uiuc.edu/~vadve">Vikram Adve</a>.</p>
57
58
59<!-- *********************************************************************** -->
60<div class="doc_section">
61 <a name="overview"><b>Overview</b></a>
62</div>
63<!-- *********************************************************************** -->
64
65<div class="doc_text">
66
67<p>Welcome to LLVM! In order to get started, you first need to know some
68basic information.</p>
69
70<p>First, LLVM comes in two pieces. The first piece is the LLVM suite. This
71contains all of the tools, libraries, and header files needed to use the low
72level virtual machine. It contains an assembler, disassembler, bytecode
73analyzer, and bytecode optimizer. It also contains a test suite that can be
74used to test the LLVM tools and the GCC front end.</p>
75
76<p>The second piece is the GCC front end. This component provides a version of
77GCC that compiles C and C++ code into LLVM bytecode. Currently, the GCC front
78end is a modified version of GCC 3.4 (we track the GCC 3.4 development). Once
79compiled into LLVM bytecode, a program can be manipulated with the LLVM tools
80from the LLVM suite.</p>
81
82</div>
83
84<!-- *********************************************************************** -->
85<div class="doc_section">
86 <a name="quickstart"><b>Getting Started Quickly (A Summary)</b></a>
87</div>
88<!-- *********************************************************************** -->
89
90<div class="doc_text">
91
92<p>Here's the short story for getting up and running quickly with LLVM:</p>
93
94<ol>
95 <li>Install the GCC front end:
96 <ol>
97 <li><tt>cd <i>where-you-want-the-C-front-end-to-live</i></tt>
98 <li><tt>gunzip --stdout cfrontend.<i>platform</i>.tar.gz | tar -xvf -</tt>
99 <li><b>Sparc Only:</b><br>
100 <tt>cd cfrontend/sparc<br>
101 ./fixheaders</tt>
102 </ol></li>
103
104 <li>Get the Source Code
105 <ul>
106 <li>With the distributed files:
107 <ol>
108 <li><tt>cd <i>where-you-want-llvm-to-live</i></tt>
109 <li><tt>gunzip --stdout llvm.tar.gz | tar -xvf -</tt>
110 <li><tt>cd llvm</tt>
111 </ol></li>
112
113 <li>With anonymous CVS access:
114 <ol>
115 <li><tt>cd <i>where-you-want-llvm-to-live</i></tt></li>
116 <li><tt>cvs -d
117 :pserver:anon@llvm-cvs.cs.uiuc.edu:/var/cvs/llvm login</tt></li>
118 <li>Hit the return key when prompted for the password.
119 <li><tt>cvs -z3 -d :pserver:anon@llvm-cvs.cs.uiuc.edu:/var/cvs/llvm
120 co llvm</tt></li>
121 <li><tt>cd llvm</tt></li>
122 </ol></li>
123 </ul></li>
124
125 <li>Configure the LLVM Build Environment
126 <ol>
127 <li>Change directory to where you want to store the LLVM object
128 files and run <tt>configure</tt> to configure the Makefiles and
129 header files for the default platform. Useful options include:
130 <ul>
131 <li><tt>--with-llvmgccdir=<i>directory</i></tt>
132 <p>Specify where the LLVM GCC frontend is installed.</p></li>
133 <li><tt>--enable-spec2000=<i>directory</i></tt>
134 <p>Enable the SPEC2000 benchmarks for testing. The SPEC2000
135 benchmarks should be available in
136 <tt><i>directory</i></tt>.</p></li>
137 </ul>
138 </ol></li>
139
140 <li>Build the LLVM Suite:
141 <ol>
142 <li>Set your LLVM_LIB_SEARCH_PATH environment variable.
143 <li><tt>gmake -k |& tee gnumake.out
144 &nbsp;&nbsp;&nbsp;# this is csh or tcsh syntax</tt>
145 </ol>
146
147</ol>
148
149<p>Consult the <a href="starting">Getting Started with LLVM</a> section for
150detailed information on configuring and compiling LLVM. See <a
151href="#environment">Setting Up Your Environment</a> for tips that simplify
152working with the GCC front end and LLVM tools. Go to <a href="#layout">Program
153Layout</a> to learn about the layout of the source code tree.</p>
154
155</div>
156
157<!-- *********************************************************************** -->
158<div class="doc_section">
159 <a name="requirements"><b>Requirements</b></a>
160</div>
161<!-- *********************************************************************** -->
162
163<div class="doc_text">
164
165<p>Before you begin to use the LLVM system, review the requirements given below.
166This may save you some trouble by knowing ahead of time what hardware and
167software you will need.</p>
168
169</div>
170
171<!-- ======================================================================= -->
172<div class="doc_subsection">
173 <a name="hardware"><b>Hardware</b></a>
174</div>
175
176<div class="doc_text">
177
178<p>LLVM is known to work on the following platforms:</p>
179
180<ul>
181
182 <li>Linux on x86 (Pentium and above)
183 <ul>
184 <li>Approximately 760 MB of Free Disk Space
185 <ul>
186 <li>Source code: 30 MB</li>
187 <li>Object code: 670 MB</li>
188 <li>GCC front end: 60 MB</li>
189 </ul></li>
190 </ul></li>
191
192 <li>Solaris on SparcV9 (Ultrasparc)
193 <ul>
194 <li>Approximately 1.24 GB of Free Disk Space
195 <ul>
196 <li>Source code: 30 MB</li>
197 <li>Object code: 1000 MB</li>
198 <li>GCC front end: 210 MB</li>
199 </ul></li>
200 </ul></li>
201
202</ul>
203
204<p>The LLVM suite <i>may</i> compile on other platforms, but it is not
205guaranteed to do so. If compilation is successful, the LLVM utilities should be
206able to assemble, disassemble, analyze, and optimize LLVM bytecode. Code
207generation should work as well, although the generated native code may not work
208on your platform.</p>
209
210<p>The GCC front end is not very portable at the moment. If you want to get it
211to work on another platform, you can download a copy of the source and try to
212compile it on your platform.</p>
213
214</div>
215
216<!-- ======================================================================= -->
217<div class="doc_subsection">
218 <a name="software"><b>Software</b></a>
219</div>
220
221<div class="doc_text">
222
223<p>Compiling LLVM requires that you have several software packages
224installed:</p>
225
226<ul>
227 <li><a href="http://gcc.gnu.org">GCC 3.x with C and C++ language
228 support</a></li>
229
230 <li><a href="http://savannah.gnu.org/projects/make">GNU Make</a></li>
231
232 <li><a href="http://www.gnu.org/software/flex">Flex</a></li>
233
234 <li><a href="http://www.gnu.org/software/bison/bison.html">Bison</a></li>
235</ul>
236
237<p>There are some additional tools that you may want to have when working with
238LLVM:</p>
239
240<ul>
241 <li><A href="http://www.gnu.org/software/autoconf">GNU Autoconf</A>
242 <li><A href="http://savannah.gnu.org/projects/m4">GNU M4</A>
243
244 <p>If you want to make changes to the configure scripts, you will need GNU
245 autoconf (2.57 or higher), and consequently, GNU M4 (version 1.4 or
246 higher).</p></li>
247
248 <li><A href="http://www.codesourcery.com/qm/qmtest">QMTest</A></li>
249 <li><A href="http://www.python.org">Python</A>
250
251 <p>These are needed to use the LLVM test suite.</p></li>
252
253</ul>
254
255
256<p>The remainder of this guide is meant to get you up and running with
257LLVM and to give you some basic information about the LLVM environment.
258A <a href="#starting">complete guide to installation</a> is provided in the
259next section.</p>
260
261<p>The later sections of this guide describe the <a
262href="#layout">general layout</a> of the the LLVM source tree, a <a
263href="#tutorial">simple example</a> using the LLVM tool chain, and <a
264href="#links">links</a> to find more information about LLVM or to get
265help via e-mail.</p>
266
267</div>
268
269<!-- *********************************************************************** -->
270<div class="doc_section">
271 <a name="starting"><b>Getting Started with LLVM</b></a>
272</div>
273<!-- *********************************************************************** -->
274
275<!-- ======================================================================= -->
276<div class="doc_subsection">
277 <a name="terminology">Terminology and Notation</a>
278</div>
279
280<div class="doc_text">
281
282<p>Throughout this manual, the following names are used to denote paths
283specific to the local system and working environment. <i>These are not
284environment variables you need to set but just strings used in the rest
285of this document below</i>. In any of the examples below, simply replace
286each of these names with the appropriate pathname on your local system.
287All these paths are absolute:</p>
288
289<dl compact>
290 <dt>SRC_ROOT
291 <dd>
292 This is the top level directory of the LLVM source tree.
John Criswell0f6d7c02003-10-27 18:18:16 +0000[diff] [blame]293 <p>
294
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]295 <dt>OBJ_ROOT
296 <dd>
297 This is the top level directory of the LLVM object tree (i.e. the
298 tree where object files and compiled programs will be placed. It
299 can be the same as SRC_ROOT).
300 <p>
301
302 <dt>LLVMGCCDIR
303 <dd>
304 This is the where the LLVM GCC Front End is installed.
305 <p>
306 For the pre-built GCC front end binaries, the LLVMGCCDIR is
307 <tt>cfrontend/<i>platform</i>/llvm-gcc</tt>.
308</dl>
309
310</div>
311
312<!-- ======================================================================= -->
313<div class="doc_subsection">
314 <a name="environment">Setting Up Your Environment</a>
315</div>
316
317<div class="doc_text">
318
319<p>
320In order to compile and use LLVM, you will need to set some environment
321variables. There are also some shell aliases which you may find useful.
322You can set these on the command line, or better yet, set them in your
323<tt>.cshrc</tt> or <tt>.profile</tt>.
324
325<dl compact>
326 <dt><tt>LLVM_LIB_SEARCH_PATH</tt>=<tt><i>LLVMGCCDIR</i>/bytecode-libs</tt>
327 <dd>
328 This environment variable helps the LLVM GCC front end find bytecode
329 libraries that it will need for compilation.
330 <p>
331
332 <dt>alias llvmgcc <i>LLVMGCCDIR</i><tt>/bin/gcc</tt>
333 <dt>alias llvmg++ <i>LLVMGCCDIR</i><tt>/bin/g++</tt>
334 <dd>
335 This alias allows you to use the LLVM C and C++ front ends without putting
336 them in your <tt>PATH</tt> or typing in their complete pathnames.
337</dl>
338
339</div>
340
341<!-- ======================================================================= -->
342<div class="doc_subsection">
343 <a name="unpack">Unpacking the LLVM Archives</a></h3>
344</div>
345
346<div class="doc_text">
347
348<p>
349If you have the LLVM distribution, you will need to unpack it before you
350can begin to compile it. LLVM is distributed as a set of three files. Each
351file is a TAR archive that is compressed with the gzip program.
352</p>
353
354<p> The three files are as follows:
355<dl compact>
356 <dt>llvm.tar.gz
357 <dd>This is the source code to the LLVM suite.
358 <p>
359
360 <dt>cfrontend.sparc.tar.gz
361 <dd>This is the binary release of the GCC front end for Solaris/Sparc.
362 <p>
363
364 <dt>cfrontend.x86.tar.gz
365 <dd>This is the binary release of the GCC front end for Linux/x86.
366</dl>
367
368</div>
369
370<!-- ======================================================================= -->
371<div class="doc_subsection">
372 <a name="checkout">Checkout LLVM from CVS</a></h3>
373</div>
374
375<div class="doc_text">
376
377<p>If you have access to our CVS repository, you can get a fresh copy of
378the entire source code. All you need to do is check it out from CVS as
379follows:</p>
380
381<ul>
382<li><tt>cd <i>where-you-want-llvm-to-live</i></tt>
383 <li><tt>cvs -d :pserver:anon@llvm-cvs.cs.uiuc.edu:/var/cvs/llvm login</tt>
384 <li>Hit the return key when prompted for the password.
385 <li><tt>cvs -z3 -d :pserver:anon@llvm-cvs.cs.uiuc.edu:/var/cvs/llvm co
386 llvm</tt>
387</ul>
388
389<p>This will create an '<tt>llvm</tt>' directory in the current
390directory and fully populate it with the LLVM source code, Makefiles,
391test directories, and local copies of documentation files.</p>
392
393<p>Note that the GCC front end is not included in the CVS repository. You
394should have downloaded the binary distribution for your platform.</p>
395
396</div>
397
398<!-- ======================================================================= -->
399<div class="doc_subsection">
400 <a name="installcf">Install the GCC Front End</a></h3>
401</div>
402
403<div class="doc_text">
404
405<p>Before configuring and compiling the LLVM suite, you need to extract the LLVM
406GCC front end from the binary distribution. It is used for building the
407bytecode libraries later used by the GCC front end for linking programs, and its
408location must be specified when the LLVM suite is configured.</p>
409
410<p>To install the GCC front end, do the following:</p>
411
412<ol>
413 <li><tt>cd <i>where-you-want-the-front-end-to-live</i></tt></li>
414 <li><tt>gunzip --stdout cfrontend.<i>platform</i>.tar.gz | tar -xvf
415 -</tt></li>
416</ol>
417
418<p>If you are on a Sparc/Solaris machine, you will need to fix the header
419files:</p>
420
421<p><tt>cd cfrontend/sparc<br>
422 ./fixheaders</tt></p>
423
424<p>The binary versions of the GCC front end may not suit all of your needs. For
425example, the binary distribution may include an old version of a system header
426file, not "fix" a header file that needs to be fixed for GCC, or it may be
427linked with libraries not available on your system.</p>
428
429<p>In cases like these, you may want to try <a
430href="CFEBuildInstrs.html">building the GCC front end from source.</a> This is
431not for the faint of heart, so be forewarned.</p>
432
433</div>
434
435<!-- ======================================================================= -->
436<div class="doc_subsection">
437 <a name="config">Local LLVM Configuration</a>
438</div>
439
440<div class="doc_text">
441
442<p>Once checked out from the CVS repository, the LLVM suite source code must be
443configured via the <tt>configure</tt> script. This script sets variables in
444<tt>llvm/Makefile.config</tt> and <tt>llvm/include/Config/config.h</tt>. It
445also populates <i>OBJ_ROOT</i> with the Makefiles needed to build LLVM.</p>
446
447<p>The following environment variables are used by the <tt>configure</tt>
448script to configure the build system:</p>
449
450<table border=1>
451 <tr>
452 <th>Variable</th>
453 <th>Purpose</th>
454 </tr>
455
456 <tr>
457 <td>CC</td>
458 <td>Tells <tt>configure</tt> which C compiler to use. By default,
459 <tt>configure</tt> will look for the first GCC C compiler in
460 <tt>PATH</tt>. Use this variable to override
461 <tt>configure</tt>'s default behavior.</td>
462 </tr>
463
464 <tr>
465 <td>CXX</td>
466 <td>Tells <tt>configure</tt> which C++ compiler to use. By default,
467 <tt>configure</tt> will look for the first GCC C++ compiler in
468 <tt>PATH</tt>. Use this variable to override
469 <tt>configure</tt>'s default behavior.</td>
470 </tr>
471</table>
472
473<p>The following options can be used to set or enable LLVM specific options:</p>
474
475<dl compact>
476 <dt><i>--with-llvmgccdir=LLVMGCCDIR</i>
477 <dd>
478 Path to the location where the LLVM C front end binaries and
479 associated libraries will be installed.
480 <p>
481 <dt><i>--enable-optimized</i>
482 <dd>
483 Enables optimized compilation by default (debugging symbols are removed
484 and GCC optimization flags are enabled). The default is to use an
485 unoptimized build (also known as a debug build).
486 <p>
487 <dt><i>--enable-jit</i>
488 <dd>
489 Compile the Just In Time (JIT) functionality. This is not available
490 on all platforms. The default is dependent on platform, so it is best
491 to explicitly enable it if you want it.
492 <p>
493 <dt><i>--enable-spec2000</i>
494 <dt><i>--enable-spec2000=&lt;<tt>directory</tt>&gt;</i>
495 <dd>
496 Enable the use of SPEC2000 when testing LLVM. This is disabled by default
497 (unless <tt>configure</tt> finds SPEC2000 installed). By specifying
498 <tt>directory</tt>, you can tell configure where to find the SPEC2000
499 benchmarks. If <tt>directory</tt> is left unspecified, <tt>configure</tt>
500 uses the default value
501 <tt>/home/vadve/shared/benchmarks/speccpu2000/benchspec</tt>.
502</dl>
503
504<p>To configure LLVM, follow these steps:</p>
505
506<ol>
507 <li>Change directory into the object root directory:
John Criswell0f6d7c02003-10-27 18:18:16 +0000[diff] [blame]508 <br>
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]509 <tt>cd <i>OBJ_ROOT</i></tt>
John Criswell0f6d7c02003-10-27 18:18:16 +0000[diff] [blame]510 <p>
John Criswell0f6d7c02003-10-27 18:18:16 +0000[diff] [blame]511
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]512 <li>Run the <tt>configure</tt> script located in the LLVM source tree:
513 <br>
514 <tt><i>SRC_ROOT</i>/configure</tt>
John Criswell0f6d7c02003-10-27 18:18:16 +0000[diff] [blame]515 <p>
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]516</ol>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]517
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]518<p>In addition to running <tt>configure</tt>, you must set the
519<tt>LLVM_LIB_SEARCH_PATH</tt> environment variable in your startup scripts.
520This environment variable is used to locate "system" libraries like
521"<tt>-lc</tt>" and "<tt>-lm</tt>" when linking. This variable should be set to
522the absolute path for the bytecode-libs subdirectory of the GCC front end
523install, or <i>LLVMGCCDIR</i>/bytecode-libs. For example, one might set
524<tt>LLVM_LIB_SEARCH_PATH</tt> to
525<tt>/home/vadve/lattner/local/x86/llvm-gcc/bytecode-libs</tt> for the X86
526version of the GCC front end on our research machines.</p>
John Criswell7a73b802003-06-30 21:59:07 +0000[diff] [blame]527
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]528</div>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]529
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]530<!-- ======================================================================= -->
531<div class="doc_subsection">
532 <a name="compile">Compiling the LLVM Suite Source Code</a>
533</div>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]534
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]535<div class="doc_text">
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]536
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]537<p>Once you have configured LLVM, you can build it. There are three types of
538builds:</p>
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]539
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]540<dl compact>
541 <dt>Debug Builds
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]542 <dd>
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]543 These builds are the default when one types <tt>gmake</tt> (unless the
544 <tt>--enable-optimized</tt> option was used during configuration). The
545 build system will compile the tools and libraries with debugging
546 information.
547 <p>
548
549 <dt>Release (Optimized) Builds
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]550 <dd>
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]551 These builds are enabled with the <tt>--enable-optimized</tt> option to
552 <tt>configure</tt> or by specifying <tt>ENABLE_OPTIMIZED=1</tt> on the
553 <tt>gmake</tt> command line. For these builds, the build system will
554 compile the tools and libraries with GCC optimizations enabled and strip
555 debugging information from the libraries and executables it generates.
556 <p>
557
558 <dt>Profile Builds
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]559 <dd>
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]560 These builds are for use with profiling. They compile profiling
561 information into the code for use with programs like <tt>gprof</tt>.
562 Profile builds must be started by specifying <tt>ENABLE_PROFILING=1</tt>
563 on the <tt>gmake</tt> command line.
564</dl>
John Criswell7a73b802003-06-30 21:59:07 +0000[diff] [blame]565
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]566<p>Once you have LLVM configured, you can build it by entering the
567<i>OBJ_ROOT</i> directory and issuing the following command:</p>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]568
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]569<p><tt>gmake</tt></p>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]570
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]571<p>If you have multiple processors in your machine, you may wish to use some of
572the parallel build options provided by GNU Make. For example, you could use the
573command:</p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]574
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]575<p><tt>gmake -j2</tt></p>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]576
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]577<p>There are several special targets which are useful when working with the LLVM
578source code:</p>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]579
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]580<dl compact>
581 <dt><tt>gmake clean</tt>
582 <dd>
583 Removes all files generated by the build. This includes object files,
584 generated C/C++ files, libraries, and executables.
585 <p>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]586
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]587 <dt><tt>gmake distclean</tt>
588 <dd>
589 Removes everything that <tt>gmake clean</tt> does, but also removes
590 files generated by <tt>configure</tt>. It attempts to return the
591 source tree to the original state in which it was shipped.
592 <p>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]593
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]594 <dt><tt>gmake install</tt>
595 <dd>
596 Installs LLVM files into the proper location. For the most part,
597 this does nothing, but it does install bytecode libraries into the
598 GCC front end's bytecode library directory. If you need to update
599 your bytecode libraries, this is the target to use once you've built
600 them.
601 <p>
602</dl>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]603
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]604<p>It is also possible to override default values from <tt>configure</tt> by
605declaring variables on the command line. The following are some examples:</p>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]606
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]607<dl compact>
608 <dt><tt>gmake ENABLE_OPTIMIZED=1</tt>
609 <dd>
610 Perform a Release (Optimized) build.
611 <p>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]612
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]613 <dt><tt>gmake ENABLE_PROFILING=1</tt>
614 <dd>
615 Perform a Profiling build.
616 <p>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]617
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]618 <dt><tt>gmake VERBOSE=1</tt>
619 <dd>
620 Print what <tt>gmake</tt> is doing on standard output.
621 <p>
622</dl>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]623
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]624<p>Every directory in the LLVM object tree includes a <tt>Makefile</tt> to build
625it and any subdirectories that it contains. Entering any directory inside the
626LLVM object tree and typing <tt>gmake</tt> should rebuild anything in or below
627that directory that is out of date.</p>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]628
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]629</div>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]630
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]631<!-- ======================================================================= -->
632<div class="doc_subsection">
633 <a name="objfiles">The Location of LLVM Object Files</a>
634</div>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]635
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]636<div class="doc_text">
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]637
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]638<p>The LLVM build system is capable of sharing a single LLVM source tree among
639several LLVM builds. Hence, it is possible to build LLVM for several different
640platforms or configurations using the same source tree.</p>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]641
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]642<p>This is accomplished in the typical autoconf manner:</p>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]643
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]644<ul>
645 <li><p>Change directory to where the LLVM object files should live:</p>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]646
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]647 <p><tt>cd <i>OBJ_ROOT</i></tt></p></li>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]648
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]649 <li><p>Run the <tt>configure</tt> script found in the LLVM source
650 directory:</p>
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]651
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]652 <p><tt><i>SRC_ROOT</i>/configure</tt></p></li>
653</ul>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]654
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]655<p>The LLVM build will place files underneath <i>OBJ_ROOT</i> in directories
656named after the build type:</p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]657
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]658<dl compact>
659 <dt>Debug Builds
660 <dd>
661 <dl compact>
662 <dt>Tools
663 <dd><tt><i>OBJ_ROOT</i>/tools/Debug</tt>
664 <dt>Libraries
665 <dd><tt><i>OBJ_ROOT</i>/lib/Debug</tt>
666 </dl>
667 <p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]668
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]669 <dt>Release Builds
670 <dd>
671 <dl compact>
672 <dt>Tools
673 <dd><tt><i>OBJ_ROOT</i>/tools/Release</tt>
674 <dt>Libraries
675 <dd><tt><i>OBJ_ROOT</i>/lib/Release</tt>
676 </dl>
677 <p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]678
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]679 <dt>Profile Builds
680 <dd>
681 <dl compact>
682 <dt>Tools
683 <dd><tt><i>OBJ_ROOT</i>/tools/Profile</tt>
684 <dt>Libraries
685 <dd><tt><i>OBJ_ROOT</i>/lib/Profile</tt>
686 </dl>
687</dl>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]688
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]689</div>
Chris Lattner7fe7f812002-07-24 19:51:14 +0000[diff] [blame]690
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]691<!-- *********************************************************************** -->
692<div class="doc_section">
693 <a name="layout"><b>Program Layout</b></a>
694</div>
695<!-- *********************************************************************** -->
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]696
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]697<div class="doc_text">
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]698
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]699<p>One useful source of information about the LLVM source base is the LLVM <a
700href="http://www.doxygen.org">doxygen</a> documentation, available at <tt><a
701href="http://llvm.cs.uiuc.edu/doxygen/">http://llvm.cs.uiuc.edu/doxygen/</a></tt>.
702The following is a brief introduction to code layout:</p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]703
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]704</div>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]705
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]706<!-- ======================================================================= -->
707<div class="doc_subsection">
708 <a name="cvsdir"><tt>CVS</tt> directories</a>
709</div>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]710
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]711<div class="doc_text">
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]712
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]713<p>Every directory checked out of CVS will contain a <tt>CVS</tt> directory; for
714the most part these can just be ignored.</p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]715
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]716</div>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]717
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]718<!-- ======================================================================= -->
719<div class="doc_subsection">
720 <a name="include"><tt>llvm/include</tt></a>
721</div>
722
723<div class="doc_text">
724
725<p>This directory contains public header files exported from the LLVM
726library. The three main subdirectories of this directory are:</p>
727
728<ol>
729 <li><tt>llvm/include/llvm</tt> - This directory contains all of the LLVM
730 specific header files. This directory also has subdirectories for
731 different portions of LLVM: <tt>Analysis</tt>, <tt>CodeGen</tt>,
732 <tt>Target</tt>, <tt>Transforms</tt>, etc...</li>
733
734 <li><tt>llvm/include/Support</tt> - This directory contains generic
735 support libraries that are independent of LLVM, but are used by LLVM.
736 For example, some C++ STL utilities and a Command Line option processing
737 library store their header files here.</li>
738
739 <li><tt>llvm/include/Config</tt> - This directory contains header files
740 configured by the <tt>configure</tt> script. They wrap "standard" UNIX
741 and C header files. Source code can include these header files which
742 automatically take care of the conditional #includes that the
743 <tt>configure</tt> script generates.</li>
744</ol>
745
746</div>
747
748<!-- ======================================================================= -->
749<div class="doc_subsection">
750 <a name="lib"><tt>llvm/lib</tt></a>
751</div>
752
753<div class="doc_text">
754
755<p>This directory contains most of the source files of the LLVM system. In LLVM,
756almost all code exists in libraries, making it very easy to share code among the
757different <a href="#tools">tools</a>.</p>
758
759<dl compact>
760 <dt><tt>llvm/lib/VMCore/</tt><dd> This directory holds the core LLVM
761 source files that implement core classes like Instruction and BasicBlock.
762
763 <dt><tt>llvm/lib/AsmParser/</tt><dd> This directory holds the source code
764 for the LLVM assembly language parser library.
765
766 <dt><tt>llvm/lib/ByteCode/</tt><dd> This directory holds code for reading
767 and write LLVM bytecode.
768
769 <dt><tt>llvm/lib/CWriter/</tt><dd> This directory implements the LLVM to C
770 converter.
771
772 <dt><tt>llvm/lib/Analysis/</tt><dd> This directory contains a variety of
773 different program analyses, such as Dominator Information, Call Graphs,
774 Induction Variables, Interval Identification, Natural Loop Identification,
775 etc...
776
777 <dt><tt>llvm/lib/Transforms/</tt><dd> This directory contains the source
778 code for the LLVM to LLVM program transformations, such as Aggressive Dead
779 Code Elimination, Sparse Conditional Constant Propagation, Inlining, Loop
780 Invariant Code Motion, Dead Global Elimination, and many others...
781
782 <dt><tt>llvm/lib/Target/</tt><dd> This directory contains files that
783 describe various target architectures for code generation. For example,
784 the llvm/lib/Target/Sparc directory holds the Sparc machine
785 description.<br>
786
787 <dt><tt>llvm/lib/CodeGen/</tt><dd> This directory contains the major parts
788 of the code generator: Instruction Selector, Instruction Scheduling, and
789 Register Allocation.
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]790
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]791 <dt><tt>llvm/lib/Support/</tt><dd> This directory contains the source code
792 that corresponds to the header files located in
793 <tt>llvm/include/Support/</tt>.
794</dl>
John Criswell7a73b802003-06-30 21:59:07 +0000[diff] [blame]795
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]796</div>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]797
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]798<!-- ======================================================================= -->
799<div class="doc_subsection">
800 <a name="runtime"><tt>llvm/runtime</tt></a>
801</div>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]802
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]803<div class="doc_text">
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]804
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]805<p>This directory contains libraries which are compiled into LLVM bytecode and
806used when linking programs with the GCC front end. Most of these libraries are
807skeleton versions of real libraries; for example, libc is a stripped down
808version of glibc.</p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]809
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]810<p>Unlike the rest of the LLVM suite, this directory needs the LLVM GCC front
811end to compile.</p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]812
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]813</div>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]814
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]815<!-- ======================================================================= -->
816<div class="doc_subsection">
817 <a name="test"><tt>llvm/test</tt></a>
818</div>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]819
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]820<div class="doc_text">
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]821
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]822<p>This directory contains regression tests and source code that is used to test
823the LLVM infrastructure.</p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]824
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]825</div>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]826
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]827<!-- ======================================================================= -->
828<div class="doc_subsection">
829 <a name="tools"><tt>llvm/tools</tt></a>
830</div>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]831
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]832<div class="doc_text">
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]833
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]834<p>The <b>tools</b> directory contains the executables built out of the
835libraries above, which form the main part of the user interface. You can
836always get help for a tool by typing <tt>tool_name --help</tt>. The
837following is a brief introduction to the most important tools.</p>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]838
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]839<dl compact>
840 <dt>
John Criswell20d2d3e2003-10-10 14:26:14 +0000[diff] [blame]841
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]842 <dt><tt><b>analyze</b></tt><dd> <tt>analyze</tt> is used to run a specific
843 analysis on an input LLVM bytecode file and print out the results. It is
844 primarily useful for debugging analyses, or familiarizing yourself with
845 what an analysis does.<p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]846
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]847 <dt><tt><b>bugpoint</b></tt><dd> <tt>bugpoint</tt> is used to debug
848 optimization passes or code generation backends by narrowing down the
849 given test case to the minimum number of passes and/or instructions that
850 still cause a problem, whether it is a crash or miscompilation. See <a
851 href="HowToSubmitABug.html">HowToSubmitABug.html</a> for more information
852 on using <tt>bugpoint</tt>.<p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]853
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]854 <dt><tt><b>llvm-ar</b></tt><dd>The archiver produces an archive containing
855 the given LLVM bytecode files, optionally with an index for faster
856 lookup.<p>
857
858 <dt><tt><b>llvm-as</b></tt><dd>The assembler transforms the human readable
859 LLVM assembly to LLVM bytecode.<p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]860
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]861 <dt><tt><b>llvm-dis</b></tt><dd>The disassembler transforms the LLVM
862 bytecode to human readable LLVM assembly. Additionally, it can convert
863 LLVM bytecode to C, which is enabled with the <tt>-c</tt> option.<p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]864
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]865 <dt><tt><b>llvm-link</b></tt><dd> <tt>llvm-link</tt>, not surprisingly,
866 links multiple LLVM modules into a single program.<p>
867
868 <dt><tt><b>lli</b></tt><dd> <tt>lli</tt> is the LLVM interpreter, which
869 can directly execute LLVM bytecode (although very slowly...). In addition
870 to a simple interpreter, <tt>lli</tt> also has a tracing mode (entered by
871 specifying <tt>-trace</tt> on the command line). Finally, for
872 architectures that support it (currently only x86 and Sparc), by default,
873 <tt>lli</tt> will function as a Just-In-Time compiler (if the
874 functionality was compiled in), and will execute the code <i>much</i>
875 faster than the interpreter.<p>
Misha Brukmanef0ad412003-10-06 19:23:34 +0000[diff] [blame]876
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]877 <dt><tt><b>llc</b></tt><dd> <tt>llc</tt> is the LLVM backend compiler,
878 which translates LLVM bytecode to a SPARC or x86 assembly file.<p>
Misha Brukmanef0ad412003-10-06 19:23:34 +0000[diff] [blame]879
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]880 <dt><tt><b>llvmgcc</b></tt><dd> <tt>llvmgcc</tt> is a GCC-based C frontend
881 that has been retargeted to emit LLVM code as the machine code output. It
882 works just like any other GCC compiler, taking the typical <tt>-c, -S, -E,
883 -o</tt> options that are typically used. The source code for the
884 <tt>llvmgcc</tt> tool is currently not included in the LLVM CVS tree
885 because it is quite large and not very interesting.<p>
Misha Brukmanef0ad412003-10-06 19:23:34 +0000[diff] [blame]886
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]887 <ol>
888 <dt><tt><b>gccas</b></tt><dd> This tool is invoked by the
889 <tt>llvmgcc</tt> frontend as the "assembler" part of the compiler. This
890 tool actually assembles LLVM assembly to LLVM bytecode,
891 performs a variety of optimizations, and outputs LLVM bytecode. Thus
892 when you invoke <tt>llvmgcc -c x.c -o x.o</tt>, you are causing
893 <tt>gccas</tt> to be run, which writes the <tt>x.o</tt> file (which is
894 an LLVM bytecode file that can be disassembled or manipulated just like
895 any other bytecode file). The command line interface to <tt>gccas</tt>
896 is designed to be as close as possible to the <b>system</b>
897 `<tt>as</tt>' utility so that the gcc frontend itself did not have to be
898 modified to interface to a "weird" assembler.<p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]899
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]900 <dt><tt><b>gccld</b></tt><dd> <tt>gccld</tt> links together several LLVM
901 bytecode files into one bytecode file and does some optimization. It is
902 the linker invoked by the GCC frontend when multiple .o files need to be
903 linked together. Like <tt>gccas</tt>, the command line interface of
904 <tt>gccld</tt> is designed to match the system linker, to aid
905 interfacing with the GCC frontend.<p>
906 </ol>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]907
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]908 <dt><tt><b>opt</b></tt><dd> <tt>opt</tt> reads LLVM bytecode, applies a
909 series of LLVM to LLVM transformations (which are specified on the command
910 line), and then outputs the resultant bytecode. The '<tt>opt --help</tt>'
911 command is a good way to get a list of the program transformations
912 available in LLVM.<p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]913
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]914</dl>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]915
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]916</div>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]917
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]918<!-- ======================================================================= -->
919<div class="doc_subsection">
920 <a name="utils"><tt>llvm/utils</tt></a>
921</div>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]922
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]923<div class="doc_text">
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]924
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]925<p>This directory contains utilities for working with LLVM source code, and some
926of the utilities are actually required as part of the build process because they
927are code generators for parts of LLVM infrastructure.</p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]928
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]929<dl compact>
930 <td><tt><b>Burg/</b></tt><dd> <tt>Burg</tt> is an instruction selector
931 generator -- it builds trees on which it then performs pattern-matching to
932 select instructions according to the patterns the user has specified. Burg
933 is currently used in the Sparc V9 backend.<p>
John Criswell0b459202003-07-08 20:35:59 +0000[diff] [blame]934
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]935 <dt><tt><b>codegen-diff</b></tt><dd> <tt>codegen-diff</tt> is a script
936 that finds differences between code that LLC generates and code that LLI
937 generates. This is a useful tool if you are debugging one of them,
938 assuming that the other generates correct output. For the full user
939 manual, run <tt>`perldoc codegen-diff'</tt>.<p>
Misha Brukmanc103adf2003-08-11 18:45:46 +0000[diff] [blame]940
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]941 <dt><tt><b>cvsupdate</b></tt><dd> <tt>cvsupdate</tt> is a script that will
942 update your CVS tree, but produce a much cleaner and more organized output
943 than simply running <tt>`cvs -z3 up -dP'</tt> will. For example, it will group
944 together all the new and updated files and modified files in separate
945 sections, so you can see at a glance what has changed. If you are at the
946 top of your LLVM CVS tree, running <tt>utils/cvsupdate</tt> is the
947 preferred way of updating the tree.<p>
Misha Brukmanc103adf2003-08-11 18:45:46 +0000[diff] [blame]948
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]949 <dt><tt><b>emacs/</b></tt><dd> The <tt>emacs</tt> directory contains
950 syntax-highlighting files which will work with Emacs and XEmacs editors,
951 providing syntax highlighting support for LLVM assembly files and TableGen
952 description files. For information on how to use the syntax files, consult
953 the <tt>README</tt> file in that directory.<p>
Misha Brukmanc103adf2003-08-11 18:45:46 +0000[diff] [blame]954
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]955 <dt><tt><b>getsrcs.sh</b></tt><dd> The <tt>getsrcs.sh</tt> script finds
956 and outputs all non-generated source files, which is useful if one wishes
957 to do a lot of development across directories and does not want to
958 individually find each file. One way to use it is to run, for example:
959 <tt>xemacs `utils/getsources.sh`</tt> from the top of your LLVM source
960 tree.<p>
961
962 <dt><tt><b>makellvm</b></tt><dd> The <tt>makellvm</tt> script compiles all
963 files in the current directory and then compiles and links the tool that
964 is the first argument. For example, assuming you are in the directory
965 <tt>llvm/lib/Target/Sparc</tt>, if <tt>makellvm</tt> is in your path,
966 simply running <tt>makellvm llc</tt> will make a build of the current
967 directory, switch to directory <tt>llvm/tools/llc</tt> and build it,
968 causing a re-linking of LLC.<p>
Misha Brukmanc103adf2003-08-11 18:45:46 +0000[diff] [blame]969
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]970 <dt><tt><b>NightlyTest.pl</b></tt> and
971 <tt><b>NightlyTestTemplate.html</b></tt><dd> These files are used in a
972 cron script to generate nightly status reports of the functionality of
973 tools, and the results can be seen by following the appropriate link on
974 the <a href="http://llvm.cs.uiuc.edu/">LLVM homepage</a>.<p>
Misha Brukmanc103adf2003-08-11 18:45:46 +0000[diff] [blame]975
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]976 <dt><tt><b>TableGen/</b></tt><dd> The <tt>TableGen</tt> directory contains
977 the tool used to generate register descriptions, instruction set
978 descriptions, and even assemblers from common TableGen description
979 files.<p>
Misha Brukmanc103adf2003-08-11 18:45:46 +0000[diff] [blame]980
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]981 <dt><tt><b>vim/</b></tt><dd> The <tt>vim</tt> directory contains
982 syntax-highlighting files which will work with the VIM editor, providing
983 syntax highlighting support for LLVM assembly files and TableGen
984 description files. For information on how to use the syntax files, consult
985 the <tt>README</tt> file in that directory.<p>
Misha Brukmanc103adf2003-08-11 18:45:46 +0000[diff] [blame]986
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]987</dl>
Misha Brukmanc103adf2003-08-11 18:45:46 +0000[diff] [blame]988
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]989</div>
Misha Brukmanc103adf2003-08-11 18:45:46 +0000[diff] [blame]990
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]991<!-- *********************************************************************** -->
992<div class="doc_section">
993 <a name="tutorial">An Example Using the LLVM Tool Chain</a>
994</div>
995<!-- *********************************************************************** -->
Misha Brukmanc103adf2003-08-11 18:45:46 +0000[diff] [blame]996
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]997<div class="doc_text">
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]998
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]999<ol>
1000 <li>First, create a simple C file, name it 'hello.c':
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]1001 <pre>
1002 #include &lt;stdio.h&gt;
1003 int main() {
1004 printf("hello world\n");
1005 return 0;
1006 }
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1007 </pre></li>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]1008
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1009 <li><p>Next, compile the C file into a LLVM bytecode file:</p>
1010 <p><tt>% llvmgcc hello.c -o hello</tt></p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]1011
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1012 <p>This will create two result files: <tt>hello</tt> and
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]1013 <tt>hello.bc</tt>. The <tt>hello.bc</tt> is the LLVM bytecode that
1014 corresponds the the compiled program and the library facilities that it
1015 required. <tt>hello</tt> is a simple shell script that runs the bytecode
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1016 file with <tt>lli</tt>, making the result directly executable.</p></li>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]1017
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1018 <li><p>Run the program. To make sure the program ran, execute one of the
1019 following commands:</p>
John Criswell8df90e02003-06-11 20:46:40 +0000[diff] [blame]1020
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1021 <p><tt>% ./hello</tt></p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]1022
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1023 <p>or</p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]1024
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1025 <p><tt>% lli hello.bc</tt></p></li>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]1026
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1027 <li><p>Use the <tt>llvm-dis</tt> utility to take a look at the LLVM assembly
1028 code:</p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]1029
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1030 <p><tt>% llvm-dis &lt; hello.bc | less</tt><p></li>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]1031
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1032 <li><p>Compile the program to native Sparc assembly using the code
1033 generator (assuming you are currently on a Sparc system):</p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]1034
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1035 <p><tt>% llc hello.bc -o hello.s</tt></p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]1036
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1037 <li><p>Assemble the native sparc assemble file into a program:</p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]1038
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1039 <p><tt>% /opt/SUNWspro/bin/cc -xarch=v9 hello.s -o hello.sparc</tt></p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]1040
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1041 <li><p>Execute the native sparc program:</p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]1042
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1043 <p><tt>% ./hello.sparc</tt></p></li>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]1044
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1045</ol>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]1046
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1047</div>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]1048
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1049<!-- *********************************************************************** -->
1050<div class="doc_section">
1051 <a name="problems">Common Problems</a>
1052</div>
1053<!-- *********************************************************************** -->
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]1054
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1055<div class="doc_text">
John Criswellce760f62003-07-03 16:01:38 +0000[diff] [blame]1056
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1057<p>If you are having problems building or using LLVM, or if you have any other
1058general questions about LLVM, please consult the <a href="FAQ.html">Frequently
1059Asked Questions</a> page.</p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]1060
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1061</div>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]1062
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1063<!-- *********************************************************************** -->
1064<div class="doc_section">
1065 <a name="links">Links</a>
1066</div>
1067<!-- *********************************************************************** -->
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]1068
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1069<div class="doc_text">
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]1070
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1071<p>This document is just an <b>introduction</b> to how to use LLVM to do
1072some simple things... there are many more interesting and complicated things
1073that you can do that aren't documented here (but we'll gladly accept a patch
1074if you want to write something up!). For more information about LLVM, check
1075out:</p>
John Criswell85ed3612003-06-12 19:34:44 +0000[diff] [blame]1076
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1077<ul>
1078 <li><a href="http://llvm.cs.uiuc.edu/">LLVM homepage</a></li>
1079 <li><a href="http://llvm.cs.uiuc.edu/doxygen/">LLVM doxygen tree</a></li>
1080 <li><a href="http://llvm.cs.uiuc.edu/docs/Projects.html">Starting a Project
1081 that Uses LLVM</a></li>
1082</ul>
1083
1084</div>
1085
1086<!-- *********************************************************************** -->
1087
1088<hr>
Misha Brukman142207b2003-11-22 01:30:01 +0000[diff] [blame]1089<address>
1090 <a href="mailto:sabre@nondot.org">Chris Lattner</a><br>
1091 <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br>
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1092 Last modified: $Date$
Misha Brukman142207b2003-11-22 01:30:01 +0000[diff] [blame]1093</address>
Misha Brukman00c73d22003-11-07 19:43:14 +0000[diff] [blame]1094
1095</body>
Guochun Shif4688a82002-07-17 23:05:56 +0000[diff] [blame]1096</html>