| Guochun Shi | f4688a8 | 2002-07-17 23:05:56 +0000 | [diff] [blame] | 1 | <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> | 
 | 2 | <html> | 
| John Criswell | 85ed361 | 2003-06-12 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 Criswell | cb27f1e | 2003-07-01 21:55:57 +0000 | [diff] [blame] | 10 |     <a href="mailto:sabre@nondot.org">Chris Lattner</a>, | 
 | 11 |     <a href="mailto:criswell@uiuc.edu">John Criswell</a>, and | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 12 |     <a href="http://www.cs.uiuc.edu/~vadve">Vikram Adve</a> | 
 | 13 |     </font></h1></center> | 
 | 14 |  | 
 | 15 |     <!--=====================================================================--> | 
 | 16 |     <h2><a name="Contents">Contents</a></h2> | 
 | 17 |     <!--=====================================================================--> | 
 | 18 |  | 
 | 19 |     <ul> | 
 | 20 |       <li><a href="#overview">Overview</a> | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 21 |       <ol> | 
| John Criswell | 7a73b80 | 2003-06-30 21:59:07 +0000 | [diff] [blame] | 22 |           <li><a href="#requirements">Requirements</a> | 
 | 23 |           <ol> | 
 | 24 |               <li><a href="#hardware">Hardware</a> | 
 | 25 |               <li><a href="#software">Software</a> | 
 | 26 |           </ol> | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 27 |       </ol> | 
 | 28 |       <li><a href="#starting">Getting started with LLVM</a> | 
 | 29 |         <ol> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 30 |           <li><a href="#quickstart">Getting Started Quickly (A Summary)</a> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 31 |           <li><a href="#terminology">Terminology and Notation</tt></a> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 32 |           <li><a href="#environment">Setting Up Your Environment</a> | 
| John Criswell | 312a68c | 2003-07-07 19:27:35 +0000 | [diff] [blame] | 33 |           <li><a href="#unpack">Unpacking the LLVM Archives</a> | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 34 |           <li><a href="#checkout">Checkout LLVM from CVS</a> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 35 |           <li><a href="#installcf">Install the C Front End</a> | 
 | 36 |           <li><a href="#config">Local LLVM Configuration</tt></a> | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 37 |           <li><a href="#compile">Compiling the LLVM Suite Source Code</a> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 38 |           <li><a href="#objfiles">The Location of LLVM Object Files</tt></a> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 39 |         </ol> | 
 | 40 |       <li><a href="#layout">Program layout</a> | 
 | 41 | 	<ol> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 42 |       <li><a href="#cvsdir"><tt>CVS</tt> directories</a> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 43 | 	  <li><a href="#include"><tt>llvm/include</tt></a> | 
 | 44 | 	  <li><a href="#lib"><tt>llvm/lib</tt></a> | 
 | 45 | 	  <li><a href="#test"><tt>llvm/test</tt></a> | 
 | 46 | 	  <li><a href="#tools"><tt>llvm/tools</tt></a>   | 
 | 47 | 	</ol> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 48 |       <li><a href="#cfront">Compiling the LLVM C Front End</a> | 
 | 49 |       <li><a href="#tutorial">An Example Using the LLVM Tool Chain</a> | 
 | 50 |       <li><a href="#problems">Common Problems</a> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 51 |       <li><a href="#links">Links</a> | 
 | 52 |     </ul> | 
 | 53 |  | 
 | 54 |  | 
 | 55 |     <!--=====================================================================--> | 
 | 56 |     <center> | 
 | 57 |     <h2><a name="overview"><b>Overview</b></a></h2> | 
 | 58 |     </center> | 
 | 59 |     <!--=====================================================================--> | 
 | 60 |  | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 61 |     Welcome to LLVM!  In order to get started, you first need to know some | 
 | 62 |     basic information. | 
 | 63 |  | 
 | 64 |     <p> | 
 | 65 |     First, LLVM comes in two pieces.  The first piece is the LLVM suite.  This | 
 | 66 |     contains all of the tools, libraries, and header files needed to use the | 
 | 67 |     low level virtual machine.  It also contains a test suite that can be used | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 68 |     to test the LLVM tools and the C front end. | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 69 |     <p> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 70 |     The second piece is the C front end.  This component provides a version | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 71 |     of GCC that compiles C code into LLVM bytecode.  Currently, the C front end | 
 | 72 |     is a modified version of GCC 3.4 (we track the GCC 3.4 development). | 
 | 73 |     Once compiled into LLVM bytecode, a program can be manipulated with the | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 74 |     LLVM tools from the LLVM suite. | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 75 |  | 
 | 76 |     <!--=====================================================================--> | 
 | 77 |     <h3><a name="requirements"><b>Requirements</b></a></h3> | 
 | 78 |     <!--=====================================================================--> | 
 | 79 |  | 
 | 80 |     Before you begin to use the LLVM system, review the requirements given | 
 | 81 |     below.  This may save you some trouble by knowing ahead of time what | 
 | 82 |     hardware and software you will need. | 
 | 83 |  | 
 | 84 |     <!--=====================================================================--> | 
 | 85 |     <h4><a name="hardware"><b>Hardware</b></a></h4> | 
 | 86 |     <!--=====================================================================--> | 
 | 87 |     LLVM is known to work on the following platforms: | 
 | 88 |     <ul> | 
 | 89 |         <li> Linux on x86 | 
 | 90 |         <ul> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 91 |             <li> Approximately 760 MB of Free Disk Space | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 92 |             <ul> | 
 | 93 |                 <li>Source code: 30 MB | 
 | 94 |                 <li>Object code: 670 MB | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 95 |                 <li>C front end: 60 MB | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 96 |             </ul> | 
 | 97 |         </ul> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 98 |  | 
 | 99 |         <p> | 
 | 100 |  | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 101 |         <li> Solaris on SparcV9 (Ultrasparc) | 
 | 102 |         <ul> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 103 |             <li> Approximately 1.24 GB of Free Disk Space | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 104 |             <ul> | 
 | 105 |                 <li>Source code: 30 MB | 
 | 106 |                 <li>Object code: 1000 MB | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 107 |                 <li>C front end: 210 MB | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 108 |             </ul> | 
 | 109 |         </ul> | 
 | 110 |     </ul> | 
 | 111 |  | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 112 |     <p> | 
 | 113 |     If you want to compile your own version of the C front end, you will need | 
 | 114 |     additional disk space: | 
 | 115 |     </p> | 
 | 116 |  | 
 | 117 |     <ul> | 
 | 118 |         <li>Linux on x86 | 
 | 119 |         <ul> | 
 | 120 |             <li> Approximately 249 MB of Free Disk Space | 
 | 121 |             <ul> | 
 | 122 |                 <li>Source code: 146 MB | 
 | 123 |                 <li>Object code: 82 MB | 
 | 124 |                 <li>Installed binaries: 21 MB | 
 | 125 |             </ul> | 
 | 126 |         </ul> | 
 | 127 |  | 
 | 128 |         <p> | 
 | 129 |  | 
 | 130 |         <li>Solaris on Sparc | 
 | 131 |         <ul> | 
 | 132 |             <li> Approximately 264 MB of Free Disk Space | 
 | 133 |             <ul> | 
 | 134 |                 <li>Source code: 146 MB | 
 | 135 |                 <li>Object code: 93 MB | 
 | 136 |                 <li>Installed binaries: 25 MB | 
 | 137 |             </ul> | 
 | 138 |         </ul> | 
 | 139 |     </ul> | 
 | 140 |  | 
 | 141 |     <p> | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 142 |     LLVM <i>may</i> compile on other platforms.  The LLVM utilities should work | 
 | 143 |     on other platforms, so it should be possible to generate and produce LLVM | 
 | 144 |     bytecode on unsupported platforms (although bytecode generated on one | 
 | 145 |     platform may not work on another platform).  However, the code generators | 
| Misha Brukman | c56e582 | 2003-07-03 16:29:36 +0000 | [diff] [blame] | 146 |     and Just-In-Time (JIT) compilers only generate SparcV9 or x86 machine code. | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 147 |     </p> | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 148 |  | 
 | 149 |     <!--=====================================================================--> | 
 | 150 |     <h4><a name="software"><b>Software</b></a></h4> | 
 | 151 |     <!--=====================================================================--> | 
 | 152 |     <p> | 
| John Criswell | 6dd90d2 | 2003-07-03 16:43:01 +0000 | [diff] [blame] | 153 |  | 
 | 154 |     Unpacking the distribution requires the following tools: | 
 | 155 |     <dl compact> | 
 | 156 |         <dt>GNU Zip (gzip) | 
 | 157 |         <dt>GNU Tar | 
 | 158 |         <dd> | 
 | 159 |         These tools are needed to uncompress and unarchive the software. | 
 | 160 |         Regular Solaris <tt>tar</tt> may work for unpacking the TAR archive but | 
 | 161 |         is untested. | 
 | 162 |     </dl> | 
 | 163 |  | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 164 |     Compiling LLVM requires that you have several different software packages | 
 | 165 |     installed: | 
 | 166 |  | 
 | 167 |     <dl compact> | 
 | 168 |         <dt> GCC | 
 | 169 |         <dd> | 
 | 170 |         The GNU Compiler Collection must be installed with C and C++ language | 
 | 171 |         support.  GCC 3.2.x works, and GCC 3.x is generally supported. | 
 | 172 |  | 
 | 173 |         <p> | 
 | 174 |         Note that we currently do not support any other C++ compiler. | 
 | 175 |         </p> | 
 | 176 |  | 
 | 177 |         <dt> GNU Make | 
 | 178 |         <dd> | 
 | 179 |         The LLVM build system relies upon GNU Make extensions.  Therefore, you | 
 | 180 |         will need GNU Make (sometimes known as gmake) to build LLVM. | 
 | 181 |         <p> | 
 | 182 |  | 
 | 183 |         <dt> Flex and Bison | 
 | 184 |         <dd> | 
 | 185 |         The LLVM source code is built using flex and bison.  You will not be | 
 | 186 |         able to configure and compile LLVM without them. | 
 | 187 |         <p> | 
 | 188 |  | 
 | 189 |         <dt> GNU M4 | 
 | 190 |         <dd> | 
 | 191 |         If you are installing Bison on your machine for the first time, you | 
 | 192 |         will need GNU M4 (version 1.4 or higher). | 
 | 193 |     </dl> | 
 | 194 |  | 
 | 195 |     <p> | 
 | 196 |     There are some additional tools that you may want to have when working with | 
 | 197 |     LLVM: | 
 | 198 |     </p> | 
 | 199 |  | 
 | 200 |     <ul> | 
 | 201 |         <li>GNU Autoconf | 
 | 202 |         <li>GNU M4 | 
 | 203 |         <p> | 
 | 204 |         If you want to make changes to the configure scripts, you will need | 
 | 205 |         GNU autoconf (2.53 or higher), and consequently, GNU M4 (version 1.4 | 
 | 206 |         or higher). | 
 | 207 |         </p> | 
 | 208 |     </ul> | 
 | 209 |  | 
 | 210 |  | 
 | 211 |     <p>The <a href="starting">next section</a> of this guide is meant to get | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 212 |     you up and running with LLVM and to give you some basic information about | 
 | 213 |     the LLVM environment.  The <a href"#quickstart">first subsection</a> gives | 
 | 214 |     a short summary for those who are already familiar with the system and | 
 | 215 |     want to get started as quickly as possible. | 
 | 216 |  | 
 | 217 |     <p>The later sections of this guide describe the <a | 
| John Criswell | cb27f1e | 2003-07-01 21:55:57 +0000 | [diff] [blame] | 218 |     href="#layout">general layout</a> of the the LLVM source-tree, a <a | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 219 |     href="#tutorial">simple example</a> using the LLVM tool chain, and <a | 
 | 220 |     href="#links">links</a> to find more information about LLVM or to get | 
 | 221 |     help via e-mail. | 
 | 222 |  | 
 | 223 |     <!--=====================================================================--> | 
 | 224 |     <center> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 225 |     <h2><a name="starting"><b>Getting Started with LLVM</b></a></h2> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 226 |     </center> | 
 | 227 |     <!--=====================================================================--> | 
 | 228 |  | 
| John Criswell | 7a73b80 | 2003-06-30 21:59:07 +0000 | [diff] [blame] | 229 |     <!--=====================================================================--> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 230 |     <h3><a name="quickstart"><b>Getting Started Quickly (A Summary)</b></a></h3> | 
 | 231 |     <!--=====================================================================--> | 
 | 232 |  | 
 | 233 |     Here's the short story for getting up and running quickly with LLVM: | 
| Chris Lattner | 96768ea | 2003-02-14 04:22:13 +0000 | [diff] [blame] | 234 |     <ol> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 235 |         <li>Install the C front end: | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 236 |         <ol> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 237 |             <li><tt>cd <i>where-you-want-the-C-front-end-to-live</i></tt> | 
 | 238 |             <li><tt>gunzip --stdout cfrontend.<i>platform</i>.tar.gz | tar -xvf | 
 | 239 |             -</tt> | 
 | 240 |         </ol> | 
| John Criswell | 7a73b80 | 2003-06-30 21:59:07 +0000 | [diff] [blame] | 241 |  | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 242 |         <p> | 
 | 243 |  | 
 | 244 |         <li>Get the Source Code | 
 | 245 |         <ul> | 
 | 246 |             <li>With the distributed files: | 
 | 247 |             <ol> | 
 | 248 |                 <li><tt>cd <i>where-you-want-llvm-to-live</i></tt> | 
 | 249 |                 <li><tt>gunzip --stdout llvm.tar.gz | tar -xvf -</tt> | 
 | 250 |                 <li><tt>gunzip --stdout cfrontend.<i>platform</i>.tar.gz | tar -xvf -</tt> | 
 | 251 |                 <li><tt>cd llvm</tt> | 
 | 252 |             </ol> | 
 | 253 |  | 
 | 254 |             <p> | 
 | 255 |  | 
 | 256 |             <li>With anonymous CVS access: | 
 | 257 |             <ol> | 
 | 258 |                 <li>Find the path to the CVS repository containing LLVM (we'll call this <i>CVSROOTDIR</i>). | 
 | 259 |                 <li><tt>cd <i>where-you-want-llvm-to-live</i></tt> | 
 | 260 |                 <li><tt>cvs -d <i>CVSROOTDIR</i> checkout llvm</tt> | 
 | 261 |                 <li><tt>cd llvm</tt> | 
 | 262 |             </ol> | 
 | 263 |         </ul> | 
 | 264 |         </ul> | 
 | 265 |  | 
 | 266 |         <p> | 
 | 267 |  | 
 | 268 |         <li>Configure the LLVM Build Environment | 
 | 269 |         <ol> | 
 | 270 |             <li>Run <tt>configure</tt> to configure the Makefiles and header | 
 | 271 |             files for the default platform. | 
 | 272 |             Useful options include: | 
 | 273 |                 <ul> | 
 | 274 |                     <li><tt>--with-objroot=<i>directory</i></tt> | 
 | 275 |                     <br> | 
 | 276 |                     Specify where object files should be placed during the build. | 
 | 277 |  | 
 | 278 |                     <li><tt>--with-llvmgccdir=<i>directory</i></tt> | 
 | 279 |                     <br> | 
 | 280 |                     Specify where the LLVM C frontend is going to be installed. | 
 | 281 |                 </ul> | 
 | 282 |         </ol> | 
 | 283 |  | 
 | 284 |         <p> | 
 | 285 |  | 
 | 286 |         <li>Build the LLVM Suite | 
 | 287 |         <ol> | 
 | 288 |             <li>Set your LLVM_LIB_SEARCH_PATH environment variable. | 
 | 289 |             <li><tt>gmake -k |& tee gnumake.out | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 290 |                # this is csh or tcsh syntax</tt> | 
 | 291 |         </ol> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 292 |  | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 293 |         <p> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 294 |  | 
| Chris Lattner | 96768ea | 2003-02-14 04:22:13 +0000 | [diff] [blame] | 295 |     </ol> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 296 |  | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 297 |     <p>See <a href="#environment">Setting Up Your Environment</a> on tips to | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 298 |     simplify working with the LLVM front-end and compiled tools.  See the | 
 | 299 |     other sub-sections below for other useful details in working with LLVM, | 
 | 300 |     or go straight to <a href="#layout">Program Layout</a> to learn about the | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 301 |     layout of the source code tree.  For information on building the C front | 
 | 302 |     end yourself, see <a href="#cfront">Compiling the LLVM C Front End</a> for | 
 | 303 |     information. | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 304 |  | 
 | 305 |     <!-------------------------------------------------------------------------> | 
 | 306 |     <h3><a name="terminology">Terminology and Notation</a></h3> | 
 | 307 |     <!-------------------------------------------------------------------------> | 
 | 308 |  | 
 | 309 |     <p>Throughout this manual, the following names are used to denote paths | 
 | 310 |     specific to the local system and working environment.  <i>These are not | 
| John Criswell | 7a73b80 | 2003-06-30 21:59:07 +0000 | [diff] [blame] | 311 |     environment variables you need to set but just strings used in the rest | 
 | 312 |     of this document below</i>.  In any of the examples below, simply replace | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 313 |     each of these names with the appropriate pathname on your local system. | 
| Chris Lattner | 1db872d | 2002-09-06 16:26:13 +0000 | [diff] [blame] | 314 |     All these paths are absolute:</p> | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 315 |     <dl compact> | 
 | 316 |         <dt>CVSROOTDIR | 
 | 317 |         <dd> | 
 | 318 |         This is the path for the CVS repository containing the LLVM source | 
 | 319 |         code.  Ask the person responsible for your local LLVM installation to | 
 | 320 |         give you this path. | 
 | 321 |         <p> | 
 | 322 |  | 
 | 323 |         <dt>OBJ_ROOT | 
 | 324 |         <dd> | 
 | 325 |         This is the top level directory for where the LLVM suite object files | 
 | 326 |         will be placed during the build. | 
 | 327 |         <p> | 
 | 328 |  | 
 | 329 |         <dt>LLVMGCCDIR | 
 | 330 |         <dd> | 
 | 331 |         This is the pathname to the location where the LLVM C Front End will | 
| John Criswell | 6dd90d2 | 2003-07-03 16:43:01 +0000 | [diff] [blame] | 332 |         be installed.  Note that the C front end does not need to be installed | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 333 |         during the LLVM suite build; you will just need to know where it will | 
 | 334 |         go for configuring the build system and running the test suite later. | 
 | 335 |         <p> | 
| John Criswell | a27028b | 2003-07-03 16:49:40 +0000 | [diff] [blame] | 336 | 	For the pre-built C front end binaries, the LLVMGCCDIR is | 
 | 337 |         <tt>cfrontend/<i>platform</i>/llvm-gcc</tt>. | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 338 |  | 
 | 339 |         <dt>GCCSRC | 
 | 340 |         <dd> | 
 | 341 |         This is the pathname of the directory where the LLVM C front end source | 
 | 342 |         code can be found. | 
 | 343 |         <p> | 
 | 344 |  | 
 | 345 |         <dt>GCCOBJ | 
 | 346 |         <dd> | 
 | 347 |         This is the pathname of the directory where the LLVM C front end object | 
 | 348 |         code will be placed during the build.  It can be safely removed once | 
 | 349 |         the build is complete. | 
 | 350 |     </dl> | 
 | 351 |  | 
 | 352 |     <!-------------------------------------------------------------------------> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 353 |     <h3><a name="environment">Setting Up Your Environment</a></h3> | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 354 |     <!-------------------------------------------------------------------------> | 
 | 355 |  | 
 | 356 |     <p> | 
 | 357 |     In order to compile and use LLVM, you will need to set some environment | 
 | 358 |     variables.  There are also some shell aliases which you may find useful. | 
 | 359 |     You can set these on the command line, or better yet, set them in your | 
 | 360 |     <tt>.cshrc</tt> or <tt>.profile</tt>. | 
 | 361 |  | 
 | 362 |     <dl compact> | 
 | 363 |         <dt><tt>LLVM_LIB_SEARCH_PATH</tt>=<tt><i>LLVMGCCDIR</i>/llvm-gcc/bytecode-libs</tt> | 
 | 364 |         <dd> | 
 | 365 |         This environment variable helps the LLVM C front end find bytecode | 
 | 366 |         libraries that it will need for compilation. | 
 | 367 |         <p> | 
 | 368 |  | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 369 |         <dt>alias llvmgcc <i>LLVMGCCDIR</i><tt>/bin/llvm-gcc</tt> | 
 | 370 |         <dd> | 
 | 371 |         This alias allows you to use the LLVM C front end without putting it in | 
 | 372 |         your <tt>PATH</tt> or typing in its complete pathname. | 
 | 373 |     </dl> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 374 |  | 
 | 375 |     <!-------------------------------------------------------------------------> | 
| John Criswell | 312a68c | 2003-07-07 19:27:35 +0000 | [diff] [blame] | 376 |     <h3><a name="unpack">Unpacking the LLVM Archives</a></h3> | 
 | 377 |     <!-------------------------------------------------------------------------> | 
 | 378 |  | 
 | 379 |     <p> | 
 | 380 |     If you have the LLVM distribution, you will need to unpack it before you | 
 | 381 |     can begin to compile it.  LLVM is distributed as a set of four files.  Each | 
 | 382 |     file is a TAR archive that is compressed with the gzip program. | 
 | 383 |     </p> | 
 | 384 |  | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 385 |     <p> The four files are as follows: | 
| John Criswell | 312a68c | 2003-07-07 19:27:35 +0000 | [diff] [blame] | 386 |     <dl compact> | 
 | 387 |         <dt>llvm.tar.gz | 
 | 388 |         <dd>This is the source code to the LLVM suite. | 
 | 389 |         <p> | 
 | 390 |  | 
 | 391 |         <dt>cfrontend.sparc.tar.gz | 
 | 392 |         <dd>This is the binary release of the C front end for Solaris/Sparc. | 
 | 393 |         <p> | 
 | 394 |  | 
 | 395 |         <dt>cfrontend.x86.tar.gz | 
 | 396 |         <dd>This is the binary release of the C front end for Linux/x86. | 
 | 397 |         <p> | 
 | 398 |  | 
 | 399 |         <dt>cfrontend-src.tar.gz | 
 | 400 |         <dd>This is the source code release of the C front end. | 
 | 401 |         <p> | 
 | 402 |     </dl> | 
 | 403 |  | 
| John Criswell | 312a68c | 2003-07-07 19:27:35 +0000 | [diff] [blame] | 404 |     <!-------------------------------------------------------------------------> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 405 |     <h3><a name="checkout">Checkout LLVM from CVS</a></h3> | 
 | 406 |     <!-------------------------------------------------------------------------> | 
 | 407 |  | 
| John Criswell | 312a68c | 2003-07-07 19:27:35 +0000 | [diff] [blame] | 408 |     <p>If you have access to our CVS repository, you can get a fresh copy of | 
 | 409 |     the entire source code.  All you need to do is check it out from CVS as | 
 | 410 |     follows: | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 411 |     <ul> | 
 | 412 |     <li><tt>cd <i>where-you-want-llvm-to-live</i></tt> | 
 | 413 |     <li><tt>cvs -d <i>CVSROOTDIR</i> checkout llvm</tt></p> | 
 | 414 |     </ul> | 
 | 415 |  | 
 | 416 |     <p>This will create an '<tt>llvm</tt>' directory in the current | 
 | 417 |     directory and fully populate it with the LLVM source code, Makefiles, | 
 | 418 |     test directories, and local copies of documentation files.</p> | 
 | 419 |  | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 420 |     <p> | 
 | 421 |     Note that the C front end is not included in the CVS repository.  You | 
 | 422 |     should have either downloaded the source, or better yet, downloaded the | 
 | 423 |     binary distribution for your platform. | 
 | 424 |     </p> | 
 | 425 |  | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 426 |     <!-------------------------------------------------------------------------> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 427 |     <h3><a name="installcf">Install the C Front End</a></h3> | 
 | 428 |     <!-------------------------------------------------------------------------> | 
 | 429 |  | 
 | 430 |     <p> | 
 | 431 |     Before configuring and compiling the LLVM suite, it is best to extract the | 
 | 432 |     LLVM C front end.  While not used in building, the C front end is used by | 
 | 433 |     the LLVM test suite, and its location must be given to the | 
 | 434 |     <tt>configure</tt> script before the LLVM suite can be built. | 
 | 435 |     </p> | 
 | 436 |  | 
 | 437 |     <p> | 
 | 438 |     To install the C front end, do the following: | 
 | 439 |     <ol> | 
 | 440 |         <li><tt>cd <i>where-you-want-the-front-end-to-live</i></tt> | 
 | 441 |         <li><tt>gunzip --stdout cfrontend.<i>platform</i>.tar.gz | tar -xvf | 
 | 442 |         -</tt> | 
 | 443 |     </ol> | 
 | 444 |  | 
 | 445 |     <!-------------------------------------------------------------------------> | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 446 |     <h3><a name="config">Local LLVM Configuration</a></h3> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 447 |     <!-------------------------------------------------------------------------> | 
 | 448 |  | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 449 |     <p>Once checked out from the CVS repository, the LLVM suite source code | 
 | 450 |     must be configured via the <tt>configure</tt> script.  This script sets | 
 | 451 |     variables in <tt>llvm/Makefile.config</tt> and | 
| John Criswell | 7a73b80 | 2003-06-30 21:59:07 +0000 | [diff] [blame] | 452 |     <tt>llvm/include/Config/config.h</tt>. | 
 | 453 |  | 
 | 454 |     <p> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 455 |     The following environment variables are used by the <tt>configure</tt> | 
 | 456 |     script to configure the build system: | 
| John Criswell | 7a73b80 | 2003-06-30 21:59:07 +0000 | [diff] [blame] | 457 |     </p> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 458 |  | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 459 |     <table border=1> | 
 | 460 |         <tr> | 
 | 461 |             <th>Variable</th> | 
 | 462 |             <th> | 
 | 463 |             Purpose | 
 | 464 |             </th> | 
 | 465 |         </tr> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 466 |  | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 467 |         <tr> | 
 | 468 |             <td>CC</td> | 
 | 469 |             <td> | 
 | 470 |             Tells <tt>configure</tt> which C compiler to use.  By default, | 
 | 471 |             <tt>configure</tt> will look for the first GCC compiler in | 
 | 472 |             <tt>PATH</tt>.  Use this variable to override | 
 | 473 |             <tt>configure</tt>'s default behavior. | 
 | 474 |             </td> | 
 | 475 |         </tr> | 
 | 476 |  | 
 | 477 |         <tr> | 
 | 478 |             <td>CXX</td> | 
 | 479 |             <td> | 
 | 480 |             Tells <tt>configure</tt> which C++ compiler to use.  By default, | 
 | 481 |             <tt>configure</tt> will look for the first GCC compiler in | 
 | 482 |             <tt>PATH</tt>.  Use this variable to override | 
 | 483 |             <tt>configure</tt>'s default behavior. | 
 | 484 |             </td> | 
 | 485 |         </tr> | 
 | 486 |     </table> | 
 | 487 |  | 
 | 488 |     <p> | 
| John Criswell | 7a73b80 | 2003-06-30 21:59:07 +0000 | [diff] [blame] | 489 |     The following options can be used to set or enable LLVM specific options: | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 490 |     </p> | 
| John Criswell | 7a73b80 | 2003-06-30 21:59:07 +0000 | [diff] [blame] | 491 |  | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 492 |     <dl compact> | 
 | 493 |     <dt><i>--with-objroot=OBJ_ROOT</i> | 
 | 494 |     <dd> | 
| John Criswell | 7a73b80 | 2003-06-30 21:59:07 +0000 | [diff] [blame] | 495 |         Path to the directory where | 
 | 496 | 		object files, libraries, and executables should be placed. | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 497 |         If this is set to <tt>.</tt>, then the object files will be placed | 
 | 498 |         within the source code tree.  If left unspecified, the default value is | 
| John Criswell | ef0096f | 2003-08-08 22:36:30 +0000 | [diff] [blame] | 499 |         the following: | 
 | 500 |         <ul> | 
 | 501 |                 <li> | 
 | 502 |                 If the USER environment variable is specified and the directory | 
 | 503 |                 <tt>/localhome/$USER</tt> exists, then the default value is | 
 | 504 |                 <tt>/localhome/$USER</tt>. | 
 | 505 |  | 
 | 506 |                 <li> | 
 | 507 |                 Otherwise, the default value is <tt>.</tt>. | 
 | 508 |         </ul> | 
| John Criswell | 7a73b80 | 2003-06-30 21:59:07 +0000 | [diff] [blame] | 509 | 		(See the Section on <a href=#objfiles> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 510 | 		The Location of LLVM Object Files</a> | 
| John Criswell | 7a73b80 | 2003-06-30 21:59:07 +0000 | [diff] [blame] | 511 | 		for more information.) | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 512 |         <p> | 
 | 513 |     <dt><i>--with-llvmgccdir=LLVMGCCDIR</i> | 
 | 514 |     <dd> | 
 | 515 |         Path to the location where the LLVM C front end binaries and | 
 | 516 |         associated libraries will be installed. | 
 | 517 |         <p> | 
 | 518 |     <dt><i>--enable-optimized</i> | 
 | 519 |     <dd> | 
| John Criswell | 7a73b80 | 2003-06-30 21:59:07 +0000 | [diff] [blame] | 520 |         Enables optimized compilation (debugging symbols are removed and GCC | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 521 |         optimization flags are enabled).  The default is to use an unoptimized | 
 | 522 |         build (also known as a debug build). | 
 | 523 |         <p> | 
 | 524 |     <dt><i>--enable-jit</i> | 
 | 525 |     <dd> | 
| John Criswell | 7a73b80 | 2003-06-30 21:59:07 +0000 | [diff] [blame] | 526 |         Compile the Just In Time (JIT) functionality.  This is not available | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 527 |         on all platforms.  The default is dependent on platform, so it is best | 
 | 528 |         to explicitly enable it if you want it. | 
 | 529 |     </dl> | 
| John Criswell | 7a73b80 | 2003-06-30 21:59:07 +0000 | [diff] [blame] | 530 |  | 
 | 531 |     In addition to running <tt>configure</tt>, you must set the | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 532 |     <tt>LLVM_LIB_SEARCH_PATH</tt> environment variable in your startup scripts. | 
 | 533 |     This environment variable is used to locate "system" libraries like | 
 | 534 |     "<tt>-lc</tt>" and "<tt>-lm</tt>" when linking.  This variable should be set | 
 | 535 |     to the absolute path for the bytecode-libs subdirectory of the C front-end | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 536 |     install, or LLVMGCCDIR/llvm-gcc/bytecode-libs.  For example, one might | 
 | 537 |     set <tt>LLVM_LIB_SEARCH_PATH</tt> to | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 538 |     <tt>/home/vadve/lattner/local/x86/llvm-gcc/bytecode-libs</tt> for the X86 | 
 | 539 |     version of the C front-end on our research machines.<p> | 
 | 540 |  | 
 | 541 |     <!-------------------------------------------------------------------------> | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 542 |     <h3><a name="compile">Compiling the LLVM Suite Source Code</a></h3> | 
 | 543 |     <!-------------------------------------------------------------------------> | 
 | 544 |  | 
 | 545 |     Once you have configured LLVM, you can build it.  There are three types of | 
 | 546 |     builds: | 
 | 547 |  | 
 | 548 |     <dl compact> | 
 | 549 |         <dt>Debug Builds | 
 | 550 |         <dd> | 
 | 551 |         These builds are the default.  They compile the tools and libraries | 
 | 552 |         with debugging information. | 
 | 553 |         <p> | 
 | 554 |  | 
 | 555 |         <dt>Release (Optimized) Builds | 
 | 556 |         <dd> | 
 | 557 |         These builds are enabled with the <tt>--enable-optimized</tt> option to | 
 | 558 |         <tt>configure</tt>.  They compile the tools and libraries with GCC | 
 | 559 |         optimizer flags on and strip debugging information from the libraries | 
 | 560 |         and executables it generates.  | 
 | 561 |         <p> | 
 | 562 |  | 
 | 563 |         <dt>Profile Builds | 
 | 564 |         <dd> | 
 | 565 |         These builds are for use with profiling.  They compile profiling | 
 | 566 |         information into the code for use with programs like <tt>gprof</tt>. | 
 | 567 |         Profile builds must be started by setting variables on the | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 568 |         <tt>gmake</tt> command line. | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 569 |     </dl> | 
 | 570 |  | 
 | 571 |     Once you have LLVM configured, you can build it by entering the top level | 
 | 572 |     <tt>llvm</tt> directory and issuing the following command: | 
 | 573 |     <p> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 574 |     <tt>gmake</tt> | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 575 |  | 
 | 576 |     <p> | 
 | 577 |     If you have multiple processors in your machine, you may wish to use some | 
 | 578 |     of the parallel build options provided by GNU Make.  For example, you could | 
 | 579 |     use the command: | 
 | 580 |     </p> | 
 | 581 |  | 
 | 582 |     <p> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 583 |     <tt>gmake -j2</tt> | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 584 |  | 
 | 585 |     <p> | 
 | 586 |     There are several other targets which are useful when working with the LLVM | 
 | 587 |     source code: | 
 | 588 |  | 
 | 589 |     <dl compact> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 590 |         <dt><tt>gmake clean</tt> | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 591 |         <dd> | 
 | 592 |         Removes all files generated by the build.  This includes object files, | 
 | 593 |         generated C/C++ files, libraries, and executables. | 
 | 594 |         <p> | 
 | 595 |  | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 596 |         <dt><tt>gmake distclean</tt> | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 597 |         <dd> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 598 |         Removes everything that <tt>gmake clean</tt> does, but also removes | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 599 |         files generated by <tt>configure</tt>.  It attempts to return the | 
 | 600 |         source tree to the original state in which it was shipped. | 
 | 601 |         <p> | 
 | 602 |     </dl> | 
 | 603 |  | 
 | 604 |     It is also possible to override default values from <tt>configure</tt> by | 
 | 605 |     declaring variables on the command line.  The following are some examples: | 
 | 606 |  | 
 | 607 |     <dl compact> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 608 |         <dt><tt>gmake ENABLE_OPTIMIZED=1</tt> | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 609 |         <dd> | 
 | 610 |         Perform a Release (Optimized) build. | 
 | 611 |         <p> | 
 | 612 |  | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 613 |         <dt><tt>gmake ENABLE_PROFILING=1</tt> | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 614 |         <dd> | 
 | 615 |         Perform a Profiling build. | 
 | 616 |         <p> | 
 | 617 |  | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 618 |         <dt><tt>gmake VERBOSE=1</tt> | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 619 |         <dd> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 620 |         Print what <tt>gmake</tt> is doing on standard output. | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 621 |         <p> | 
 | 622 |     </dl> | 
 | 623 |  | 
 | 624 |     Every directory in the LLVM source tree includes a <tt>Makefile</tt> to | 
 | 625 |     build it and any subdirectories that it contains.  Entering any directory | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 626 |     inside the LLVM source tree and typing <tt>gmake</tt> should rebuild | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 627 |     anything in or below that directory that is out of date. | 
 | 628 |  | 
 | 629 |     <!-------------------------------------------------------------------------> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 630 |     <h3><a name="objfiles">The Location of LLVM Object Files</a></h3> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 631 |     <!-------------------------------------------------------------------------> | 
 | 632 |  | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 633 |     <p>The LLVM build system sends most output files generated during the build | 
 | 634 |     into the directory defined by the variable <i>OBJ_ROOT</i> in | 
 | 635 |     <tt>llvm/Makefile.config</tt>, which is set by the <i>--with-objroot</i> | 
 | 636 |     option in <tt>configure</tt>.  This can be either just your normal LLVM | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 637 |     source tree or some other directory writable by you.  You may wish to put | 
 | 638 |     object files on a different filesystem either to keep them from being backed | 
 | 639 |     up or to speed up local builds. | 
 | 640 |  | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 641 |     <p> | 
 | 642 |     If <i>OBJ_ROOT</i> is specified, then the build system will create a | 
 | 643 |     directory tree underneath it that resembles the source code's pathname | 
| John Criswell | ef0096f | 2003-08-08 22:36:30 +0000 | [diff] [blame] | 644 |     relative to your home directory (unless <i>OBJ_ROOT</i> is set to | 
 | 645 |     <tt>.</tt>, in which case object files are placed within the LLVM source | 
 | 646 |     tree). | 
 | 647 |     </p> | 
 | 648 |  | 
 | 649 |     <p> | 
 | 650 |     Note that | 
 | 651 |     <i>--with-objroot</i>=<tt>.</tt> | 
 | 652 |     and | 
 | 653 |     <i>--with-objroot</i>=<tt>`pwd`</tt> | 
 | 654 |     are not the same thing.  The former will simply place object files within | 
 | 655 |     the source tree, while the latter will set the location of object files | 
 | 656 |     using the source tree's relative path from the home directory. | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 657 |     </p> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 658 |  | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 659 |     <p> | 
 | 660 |     For example, suppose that <i>OBJ_ROOT</i> is set to <tt>/tmp</tt> and the | 
 | 661 |     LLVM suite source code is located in <tt>/usr/home/joe/src/llvm</tt>, where | 
 | 662 |     <tt>/usr/home/joe</tt> is the home directory of a user named Joe.  Then, | 
 | 663 |     the object files will be placed in <tt>/tmp/src/llvm</tt>. | 
 | 664 |     </p> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 665 |  | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 666 |     <p> | 
 | 667 |     The LLVM build will place files underneath <i>OBJ_ROOT</i> in directories | 
 | 668 |     named after the build type: | 
 | 669 |     </p> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 670 |  | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 671 |     <dl compact> | 
 | 672 |         <dt>Debug Builds | 
 | 673 |         <dd> | 
 | 674 |         <dl compact> | 
 | 675 |             <dt>Tools | 
 | 676 |             <dd><tt><i>OBJ_ROOT</i>/llvm/tools/Debug</tt> | 
 | 677 |             <dt>Libraries | 
 | 678 |             <dd><tt><i>OBJ_ROOT</i>/llvm/lib/Debug</tt> | 
 | 679 |         </dl> | 
 | 680 |         <p> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 681 |  | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 682 |         <dt>Release Builds | 
 | 683 |         <dd> | 
 | 684 |         <dl compact> | 
 | 685 |             <dt>Tools | 
 | 686 |             <dd><tt><i>OBJ_ROOT</i>/llvm/tools/Release</tt> | 
 | 687 |             <dt>Libraries | 
 | 688 |             <dd><tt><i>OBJ_ROOT</i>/llvm/lib/Release</tt> | 
 | 689 |         </dl> | 
 | 690 |         <p> | 
| Chris Lattner | 7fe7f81 | 2002-07-24 19:51:14 +0000 | [diff] [blame] | 691 |  | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 692 |         <dt>Profile Builds | 
 | 693 |         <dd> | 
 | 694 |         <dl compact> | 
 | 695 |             <dt>Tools | 
 | 696 |             <dd><tt><i>OBJ_ROOT</i>/llvm/tools/Profile</tt> | 
 | 697 |             <dt>Libraries | 
 | 698 |             <dd><tt><i>OBJ_ROOT</i>/llvm/lib/Profile</tt> | 
 | 699 |         </dl> | 
 | 700 |     </dl> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 701 |  | 
 | 702 |     <!--=====================================================================--> | 
 | 703 |     <center> | 
 | 704 |     <h2><a name="layout"><b>Program Layout</b></a></h2> | 
 | 705 |     </center> | 
 | 706 |     <!--=====================================================================--> | 
 | 707 |  | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 708 |     <p>One useful source of information about the LLVM source base is the LLVM <a | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 709 |     href="http://www.doxygen.org">doxygen</a> documentation, available at <tt><a | 
 | 710 |     href="http://llvm.cs.uiuc.edu/doxygen/">http://llvm.cs.uiuc.edu/doxygen/</a></tt>. The | 
 | 711 |     following is a brief introduction to code layout:</p> | 
 | 712 |  | 
 | 713 |  | 
 | 714 |     <!-------------------------------------------------------------------------> | 
 | 715 |     <h3><a name="cvsdir"><tt>CVS</tt> directories</a></h3> | 
 | 716 |     <!-------------------------------------------------------------------------> | 
 | 717 |  | 
 | 718 |     Every directory checked out of CVS will contain a <tt>CVS</tt> directory; | 
 | 719 |     for the most part these can just be ignored. | 
 | 720 |  | 
 | 721 |  | 
 | 722 |     <!-------------------------------------------------------------------------> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 723 |     <h3><a name="include"><tt>llvm/include</tt></a></h3> | 
 | 724 |     <!-------------------------------------------------------------------------> | 
 | 725 |  | 
 | 726 |     This directory contains public header files exported from the LLVM | 
| John Criswell | 7a73b80 | 2003-06-30 21:59:07 +0000 | [diff] [blame] | 727 |     library. The three main subdirectories of this directory are:<p> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 728 |  | 
| John Criswell | 8df90e0 | 2003-06-11 20:46:40 +0000 | [diff] [blame] | 729 |     <ol> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 730 |        <li><tt>llvm/include/llvm</tt> - This directory contains all of the LLVM | 
 | 731 |        specific header files.  This directory also has subdirectories for | 
 | 732 |        different portions of LLVM: <tt>Analysis</tt>, <tt>CodeGen</tt>, | 
 | 733 |        <tt>Reoptimizer</tt>, <tt>Target</tt>, <tt>Transforms</tt>, etc... | 
 | 734 |  | 
 | 735 |        <li><tt>llvm/include/Support</tt> - This directory contains generic | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 736 |        support libraries that are independent of LLVM, but are used by LLVM. | 
| John Criswell | 7a73b80 | 2003-06-30 21:59:07 +0000 | [diff] [blame] | 737 |        For example, some C++ STL utilities and a Command Line option processing | 
 | 738 |        library. | 
 | 739 |  | 
 | 740 |        <li><tt>llvm/include/Config</tt> - This directory contains header files | 
 | 741 |        configured by the <tt>configure</tt> script.  They wrap "standard" UNIX | 
 | 742 |        and C header files.  Source code can include these header files which | 
 | 743 |        automatically take care of the conditional #includes that the configure | 
 | 744 |        script generates. | 
| Chris Lattner | 7fe7f81 | 2002-07-24 19:51:14 +0000 | [diff] [blame] | 745 |     </ol> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 746 |  | 
 | 747 |     <!-------------------------------------------------------------------------> | 
 | 748 |     <h3><a name="lib"><tt>llvm/lib</tt></a></h3> | 
 | 749 |     <!-------------------------------------------------------------------------> | 
 | 750 |  | 
| John Criswell | 7a73b80 | 2003-06-30 21:59:07 +0000 | [diff] [blame] | 751 |     This directory contains most of the source files of the LLVM system. In | 
 | 752 |     LLVM almost all | 
 | 753 |     code exists in libraries, making it very easy to share code among the | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 754 |     different <a href="#tools">tools</a>.<p> | 
 | 755 |  | 
 | 756 |      <dl compact> | 
 | 757 |       <dt><tt>llvm/lib/VMCore/</tt><dd> This directory holds the core LLVM | 
 | 758 |       source files that implement core classes like Instruction and BasicBlock. | 
 | 759 |  | 
 | 760 |       <dt><tt>llvm/lib/AsmParser/</tt><dd> This directory holds the source code | 
 | 761 |       for the LLVM assembly language parser library. | 
 | 762 |  | 
 | 763 |       <dt><tt>llvm/lib/ByteCode/</tt><dd> This directory holds code for reading | 
 | 764 |       and write LLVM bytecode. | 
 | 765 |  | 
 | 766 |       <dt><tt>llvm/lib/CWriter/</tt><dd> This directory implements the LLVM to C | 
 | 767 |       converter. | 
 | 768 |  | 
 | 769 |       <dt><tt>llvm/lib/Analysis/</tt><dd> This directory contains a variety of | 
 | 770 |       different program analyses, such as Dominator Information, Call Graphs, | 
 | 771 |       Induction Variables, Interval Identification, Natural Loop Identification, | 
 | 772 |       etc... | 
 | 773 |  | 
 | 774 |       <dt><tt>llvm/lib/Transforms/</tt><dd> This directory contains the source | 
 | 775 |       code for the LLVM to LLVM program transformations, such as Aggressive Dead | 
 | 776 |       Code Elimination, Sparse Conditional Constant Propagation, Inlining, Loop | 
 | 777 |       Invarient Code Motion, Dead Global Elimination, Pool Allocation, and many | 
 | 778 |       others... | 
 | 779 |  | 
 | 780 |       <dt><tt>llvm/lib/Target/</tt><dd> This directory contains files that | 
 | 781 |       describe various target architectures for code generation.  For example, | 
 | 782 |       the llvm/lib/Target/Sparc directory holds the Sparc machine | 
 | 783 |       description.<br> | 
 | 784 | 	       | 
 | 785 |       <dt><tt>llvm/lib/CodeGen/</tt><dd> This directory contains the major parts | 
 | 786 |       of the code generator: Instruction Selector, Instruction Scheduling, and | 
 | 787 |       Register Allocation. | 
 | 788 |  | 
 | 789 |       <dt><tt>llvm/lib/Reoptimizer/</tt><dd> This directory holds code related | 
 | 790 |       to the runtime reoptimizer framework that is currently under development. | 
 | 791 | 	       | 
 | 792 |       <dt><tt>llvm/lib/Support/</tt><dd> This directory contains the source code | 
 | 793 |       that corresponds to the header files located in | 
 | 794 |       <tt>llvm/include/Support/</tt>. | 
 | 795 |     </dl> | 
 | 796 |  | 
 | 797 |     <!-------------------------------------------------------------------------> | 
 | 798 |     <h3><a name="test"><tt>llvm/test</tt></a></h3> | 
 | 799 |     <!-------------------------------------------------------------------------> | 
 | 800 |  | 
 | 801 |     <p>This directory contains regression tests and source code that is used to | 
 | 802 |     test the LLVM infrastructure...</p> | 
 | 803 |  | 
 | 804 |     <!-------------------------------------------------------------------------> | 
 | 805 |     <h3><a name="tools"><tt>llvm/tools</tt></a></h3> | 
 | 806 |     <!-------------------------------------------------------------------------> | 
 | 807 |  | 
 | 808 |     <p>The <b>tools</b> directory contains the executables built out of the | 
 | 809 |     libraries above, which form the main part of the user interface.  You can | 
 | 810 |     always get help for a tool by typing <tt>tool_name --help</tt>.  The | 
 | 811 |     following is a brief introduction to the most important tools.</p> | 
 | 812 |  | 
 | 813 |     <dl compact> | 
 | 814 |       <dt><tt><b>as</b></tt><dd>The assembler transforms the human readable | 
 | 815 |       LLVM assembly to LLVM bytecode.<p> | 
 | 816 |  | 
 | 817 |       <dt><tt><b>dis</b></tt><dd>The disassembler transforms the LLVM bytecode | 
 | 818 |       to human readable LLVM assembly.  Additionally it can convert LLVM | 
 | 819 |       bytecode to C, which is enabled with the <tt>-c</tt> option.<p> | 
 | 820 |  | 
 | 821 |       <dt><tt><b>lli</b></tt><dd> <tt>lli</tt> is the LLVM interpreter, which | 
 | 822 |       can directly execute LLVM bytecode (although very slowly...). In addition | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 823 |       to a simple interpreter, <tt>lli</tt> is also has debugger and tracing | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 824 |       modes (entered by specifying <tt>-debug</tt> or <tt>-trace</tt> on the | 
| Misha Brukman | c56e582 | 2003-07-03 16:29:36 +0000 | [diff] [blame] | 825 |       command line, respectively). Finally, for architectures that support it | 
 | 826 |       (currently only x86 and Sparc), by default, <tt>lli</tt> will function as | 
 | 827 |       a Just-In-Time compiler (if the functionality was compiled in), and will | 
 | 828 |       execute the code <i>much</i> faster than the interpreter.<p> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 829 |  | 
 | 830 |       <dt><tt><b>llc</b></tt><dd> <tt>llc</tt> is the LLVM backend compiler, | 
| Misha Brukman | c56e582 | 2003-07-03 16:29:36 +0000 | [diff] [blame] | 831 |       which translates LLVM bytecode to a SPARC or x86 assembly file.<p> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 832 |  | 
 | 833 |       <dt><tt><b>llvmgcc</b></tt><dd> <tt>llvmgcc</tt> is a GCC based C frontend | 
 | 834 |       that has been retargeted to emit LLVM code as the machine code output.  It | 
 | 835 |       works just like any other GCC compiler, taking the typical <tt>-c, -S, -E, | 
 | 836 |       -o</tt> options that are typically used.  The source code for the | 
 | 837 |       <tt>llvmgcc</tt> tool is currently not included in the LLVM cvs tree | 
 | 838 |       because it is quite large and not very interesting.<p> | 
 | 839 |  | 
 | 840 |       <ol> | 
 | 841 |         <dt><tt><b>gccas</b></tt><dd> This tool is invoked by the | 
 | 842 |         <tt>llvmgcc</tt> frontend as the "assembler" part of the compiler.  This | 
 | 843 |         tool actually assembles LLVM assembly to LLVM bytecode, | 
| John Criswell | 7a73b80 | 2003-06-30 21:59:07 +0000 | [diff] [blame] | 844 | 	    performs a variety of optimizations, | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 845 |         and outputs LLVM bytecode.  Thus when you invoke <tt>llvmgcc -c x.c -o | 
 | 846 |         x.o</tt>, you are causing <tt>gccas</tt> to be run, which writes the | 
 | 847 |         <tt>x.o</tt> file (which is an LLVM bytecode file that can be | 
 | 848 |         disassembled or manipulated just like any other bytecode file).  The | 
 | 849 |         command line interface to <tt>gccas</tt> is designed to be as close as | 
 | 850 |         possible to the <b>system</b> '<tt>as</tt>' utility so that the gcc | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 851 |         frontend itself did not have to be modified to interface to a "weird" | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 852 |         assembler.<p> | 
 | 853 |  | 
 | 854 |         <dt><tt><b>gccld</b></tt><dd> <tt>gccld</tt> links together several LLVM | 
 | 855 |         bytecode files into one bytecode file and does some optimization.  It is | 
 | 856 |         the linker invoked by the gcc frontend when multiple .o files need to be | 
 | 857 |         linked together.  Like <tt>gccas</tt> the command line interface of | 
 | 858 |         <tt>gccld</tt> is designed to match the system linker, to aid | 
 | 859 |         interfacing with the GCC frontend.<p> | 
 | 860 |       </ol> | 
 | 861 |  | 
 | 862 |       <dt><tt><b>opt</b></tt><dd> <tt>opt</tt> reads LLVM bytecode, applies a | 
 | 863 |       series of LLVM to LLVM transformations (which are specified on the command | 
 | 864 |       line), and then outputs the resultant bytecode.  The '<tt>opt --help</tt>' | 
 | 865 |       command is a good way to get a list of the program transformations | 
 | 866 |       available in LLVM.<p> | 
 | 867 |  | 
 | 868 |   | 
 | 869 |       <dt><tt><b>analyze</b></tt><dd> <tt>analyze</tt> is used to run a specific | 
 | 870 |       analysis on an input LLVM bytecode file and print out the results.  It is | 
 | 871 |       primarily useful for debugging analyses, or familiarizing yourself with | 
 | 872 |       what an analysis does.<p> | 
 | 873 |  | 
 | 874 |     </dl> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 875 |  | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 876 |     <!--=====================================================================--> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 877 |     <h2><center><a name="cfront">Compiling the LLVM C Front End</center></h2> | 
 | 878 |     <!--=====================================================================--> | 
 | 879 |  | 
 | 880 |     <p> | 
 | 881 |     <b> | 
 | 882 |     This step is optional if you have the C front end binary distrubtion for | 
 | 883 |     your platform. | 
 | 884 |     </b> | 
 | 885 |     </p> | 
 | 886 |  | 
 | 887 |     Now that you have the LLVM suite built, you can build the C front end.  For | 
 | 888 |     those of you that have built GCC before, the process is very similar. | 
 | 889 |     <p> | 
 | 890 |     Be forewarned, though: the build system for the C front end is not as | 
 | 891 |     polished as the rest of the LLVM code, so there will be many warnings and | 
 | 892 |     errors that you will need to ignore for now: | 
 | 893 |  | 
 | 894 |     <ol> | 
 | 895 |         <li>Ensure that <tt><i>OBJ_ROOT</i>/llvm/tools/Debug</tt> is at the | 
 | 896 |         <i>end</i> of your <tt>PATH</tt> environment variable.  The front end | 
 | 897 |         build needs to know where to find the LLVM tools, but you want to | 
 | 898 |         ensure that these tools are not found before the system assembler and | 
 | 899 |         linker that you normally use for compilation. | 
 | 900 |  | 
 | 901 |         <li><tt>cd <i>GCCOBJ</i></tt> | 
 | 902 |  | 
 | 903 |         <li>Configure the source code: | 
 | 904 |         <ul> | 
 | 905 |             <li>On Linux/x86, use | 
 | 906 |             <ul> | 
 | 907 |                 <li><tt><i>GCCSRC</i>/configure --prefix=<i>LLVMGCCDIR</i> | 
 | 908 |                 --enable-languages=c</tt> | 
 | 909 |             </ul> | 
 | 910 |  | 
 | 911 |             <li>On Solaris/Sparc, use | 
 | 912 |             <ul> | 
 | 913 |                 <li><tt><i>GCCSRC</i>/configure --prefix=<i>LLVMGCCDIR</i> | 
 | 914 |                  --enable-languages=c --target=sparcv9-sun-solaris2</tt> | 
 | 915 |             </ul> | 
 | 916 |         </ul> | 
 | 917 |  | 
 | 918 |         <li><tt>gmake</tt> | 
 | 919 |  | 
 | 920 |         <li>The build will eventually fail.  Don't worry; chances are good that | 
 | 921 |         everything that needed to build is built. | 
 | 922 |  | 
 | 923 |         <li><tt>gmake -k install</tt> | 
 | 924 |     </ol> | 
 | 925 |  | 
 | 926 |     <p> | 
 | 927 |     Once this is done, you should have a built front end compiler in | 
 | 928 |     <tt><i>LLVMGCCDIR</i></tt>. | 
 | 929 |     </p> | 
 | 930 |  | 
 | 931 |     <!--=====================================================================--> | 
 | 932 |     <h2> | 
 | 933 |     <center><a name="tutorial">An Example Using the LLVM Tool Chain</center> | 
 | 934 |     </h2> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 935 |     <!--=====================================================================--> | 
 | 936 |  | 
 | 937 |     <ol> | 
 | 938 |     <li>First, create a simple C file, name it 'hello.c': | 
 | 939 |        <pre> | 
 | 940 |    #include <stdio.h> | 
 | 941 |    int main() { | 
 | 942 |      printf("hello world\n"); | 
 | 943 |      return 0; | 
 | 944 |    } | 
 | 945 |        </pre> | 
 | 946 |  | 
 | 947 |     <li>Next, compile the C file into a LLVM bytecode file:<p> | 
 | 948 |  | 
 | 949 |       <tt>% llvmgcc hello.c -o hello</tt><p> | 
 | 950 |  | 
 | 951 |       This will create two result files: <tt>hello</tt> and | 
 | 952 |       <tt>hello.bc</tt>. The <tt>hello.bc</tt> is the LLVM bytecode that | 
 | 953 |       corresponds the the compiled program and the library facilities that it | 
 | 954 |       required.  <tt>hello</tt> is a simple shell script that runs the bytecode | 
 | 955 |       file with <tt>lli</tt>, making the result directly executable.<p> | 
 | 956 |  | 
 | 957 |     <li>Run the program. To make sure the program ran, execute one of the | 
 | 958 |     following commands:<p> | 
| John Criswell | 8df90e0 | 2003-06-11 20:46:40 +0000 | [diff] [blame] | 959 |        | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 960 |       <tt>% ./hello</tt><p> | 
 | 961 |   | 
 | 962 |       or<p> | 
 | 963 |  | 
 | 964 |       <tt>% lli hello.bc</tt><p> | 
 | 965 |  | 
 | 966 |     <li>Use the <tt>dis</tt> utility to take a look at the LLVM assembly | 
 | 967 |     code:<p> | 
 | 968 |  | 
 | 969 |       <tt>% dis < hello.bc | less</tt><p> | 
 | 970 |  | 
 | 971 |     <li>Compile the program to native Sparc assembly using the code | 
| Misha Brukman | c56e582 | 2003-07-03 16:29:36 +0000 | [diff] [blame] | 972 |     generator (assuming you are currently on a Sparc system):<p> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 973 |  | 
 | 974 |       <tt>% llc hello.bc -o hello.s</tt><p> | 
 | 975 |  | 
 | 976 |     <li>Assemble the native sparc assemble file into a program:<p> | 
 | 977 |  | 
 | 978 |       <tt>% /opt/SUNWspro/bin/cc -xarch=v9 hello.s -o hello.sparc</tt><p> | 
 | 979 |  | 
 | 980 |     <li>Execute the native sparc program:<p> | 
 | 981 |  | 
 | 982 |       <tt>% ./hello.sparc</tt><p> | 
 | 983 |  | 
 | 984 |     </ol> | 
 | 985 |  | 
 | 986 |  | 
 | 987 |     <!--=====================================================================--> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 988 |     <h2> | 
 | 989 |     <center><a name="problems">Common Problems</a></center> | 
 | 990 |     </h2> | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 991 |     <!--=====================================================================--> | 
 | 992 |  | 
 | 993 |     Below are common problems and their remedies: | 
 | 994 |  | 
 | 995 |     <dl compact> | 
 | 996 |         <dt><b>When I run configure, it finds the wrong C compiler.</b> | 
 | 997 |         <dd> | 
 | 998 |         The <tt>configure</tt> script attempts to locate first <tt>gcc</tt> and | 
 | 999 |         then <tt>cc</tt>, unless it finds compiler paths set in <tt>CC</tt> and | 
 | 1000 |         <tt>CXX</tt> for the C and C++ compiler, respectively. | 
 | 1001 |  | 
 | 1002 |         If <tt>configure</tt> finds the wrong compiler, either adjust your | 
 | 1003 |         <tt>PATH</tt> environment variable or set <tt>CC</tt> and <tt>CXX</tt> | 
 | 1004 |         explicitly. | 
 | 1005 |         <p> | 
 | 1006 |  | 
 | 1007 |         <dt><b>I compile the code, and I get some error about /localhome</b>. | 
 | 1008 |         <dd> | 
 | 1009 |         There are several possible causes for this.  The first is that you | 
 | 1010 |         didn't set a pathname properly when using <tt>configure</tt>, and it | 
 | 1011 |         defaulted to a pathname that we use on our research machines. | 
 | 1012 |         <p> | 
 | 1013 |         Another possibility is that we hardcoded a path in our Makefiles.  If | 
 | 1014 |         you see this, please email the LLVM bug mailing list with the name of | 
 | 1015 |         the offending Makefile and a description of what is wrong with it. | 
 | 1016 |  | 
 | 1017 |         <dt><b>The <tt>configure</tt> script finds the right C compiler, but it | 
 | 1018 |         uses the LLVM linker from a previous build.  What do I do?</b> | 
 | 1019 |         <dd> | 
 | 1020 |         The <tt>configure</tt> script uses the <tt>PATH</tt> to find | 
 | 1021 |         executables, so if it's grabbing the wrong linker/assembler/etc, there | 
 | 1022 |         are two ways to fix it: | 
 | 1023 |         <ol> | 
 | 1024 |             <li>Adjust your <tt>PATH</tt> environment variable so that the | 
 | 1025 |             correct program appears first in the <tt>PATH</tt>.  This may work, | 
 | 1026 |             but may not be convenient when you want them <i>first</i> in your | 
 | 1027 |             path for other work. | 
 | 1028 |             <p> | 
 | 1029 |  | 
 | 1030 |             <li>Run <tt>configure</tt> with an alternative <tt>PATH</tt> that | 
 | 1031 |             is correct.  In a Borne compatible shell, the syntax would be: | 
 | 1032 |             <p> | 
 | 1033 |             <tt>PATH=<the path without the bad program> ./configure ...</tt> | 
 | 1034 |             <p> | 
 | 1035 |             This is still somewhat inconvenient, but it allows | 
 | 1036 |             <tt>configure</tt> to do its work without having to adjust your | 
 | 1037 |             <tt>PATH</tt> permanently. | 
 | 1038 |         </ol> | 
| John Criswell | 3c852b6 | 2003-08-08 22:43:39 +0000 | [diff] [blame^] | 1039 |  | 
 | 1040 |         <dt><b>I've upgraded to a new version of LLVM, and I get strange build | 
 | 1041 |         errors.</b> | 
 | 1042 |         <dd> | 
 | 1043 |         Sometimes changes to the LLVM source code alters how the build system | 
 | 1044 |         works.  Changes in libtool, autoconf, or header file dependencies are | 
 | 1045 |         especially prone to this sort of problem. | 
 | 1046 |         <p> | 
 | 1047 |         The best thing to try is to remove the old files and re-build.  In most | 
 | 1048 |         cases, this takes care of the problem.  To do this, just type <tt>make | 
 | 1049 |         clean</tt> and then <tt>make</tt> in the directory that fails to build. | 
 | 1050 |         <p> | 
 | 1051 |  | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 1052 |     </dl> | 
 | 1053 |  | 
 | 1054 |     <!--=====================================================================--> | 
| John Criswell | 0b45920 | 2003-07-08 20:35:59 +0000 | [diff] [blame] | 1055 |     <h2><center><a name="links">Links</a></center></h2> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 1056 |     <!--=====================================================================--> | 
 | 1057 |  | 
 | 1058 |     <p>This document is just an <b>introduction</b> to how to use LLVM to do | 
 | 1059 |     some simple things... there are many more interesting and complicated things | 
 | 1060 |     that you can do that aren't documented here (but we'll gladly accept a patch | 
 | 1061 |     if you want to write something up!).  For more information about LLVM, check | 
 | 1062 |     out:</p> | 
 | 1063 |  | 
 | 1064 |     <ul> | 
 | 1065 |     <li><a href="http://llvm.cs.uiuc.edu/">LLVM homepage</a></li> | 
 | 1066 |     <li><a href="http://llvm.cs.uiuc.edu/doxygen/">LLVM doxygen tree</a></li> | 
| John Criswell | ce760f6 | 2003-07-03 16:01:38 +0000 | [diff] [blame] | 1067 |     <li><a href="http://llvm.cs.uiuc.edu/docs/Projects.html">Starting a Project that Uses LLVM</a></li> | 
| John Criswell | 85ed361 | 2003-06-12 19:34:44 +0000 | [diff] [blame] | 1068 |     </ul> | 
 | 1069 |  | 
 | 1070 |     <hr> | 
 | 1071 |  | 
 | 1072 |     If you have any questions or run into any snags (or you have any | 
 | 1073 |     additions...), please send an email to | 
 | 1074 |     <a href="mailto:sabre@nondot.org">Chris Lattner</a>.</p> | 
 | 1075 |  | 
 | 1076 | 	    <!-- Created: Mon Jul  1 02:29:02 CDT 2002 --> | 
 | 1077 | 	    <!-- hhmts start --> | 
 | 1078 | Last modified: Tue Jun  3 22:06:43 CDT 2003 | 
 | 1079 | <!-- hhmts end --> | 
 | 1080 |   </body> | 
| Guochun Shi | f4688a8 | 2002-07-17 23:05:56 +0000 | [diff] [blame] | 1081 | </html> |