running.html (13720B)
1 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> 2 <html> 3 <head> 4 <title>Running LuaJIT</title> 5 <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> 6 <meta name="Author" content="Mike Pall"> 7 <meta name="Copyright" content="Copyright (C) 2005-2016, Mike Pall"> 8 <meta name="Language" content="en"> 9 <link rel="stylesheet" type="text/css" href="bluequad.css" media="screen"> 10 <link rel="stylesheet" type="text/css" href="bluequad-print.css" media="print"> 11 <style type="text/css"> 12 table.opt { 13 line-height: 1.2; 14 } 15 tr.opthead td { 16 font-weight: bold; 17 } 18 td.flag_name { 19 width: 4em; 20 } 21 td.flag_level { 22 width: 2em; 23 text-align: center; 24 } 25 td.param_name { 26 width: 6em; 27 } 28 td.param_default { 29 width: 4em; 30 text-align: right; 31 } 32 </style> 33 </head> 34 <body> 35 <div id="site"> 36 <a href="http://luajit.org"><span>Lua<span id="logo">JIT</span></span></a> 37 </div> 38 <div id="head"> 39 <h1>Running LuaJIT</h1> 40 </div> 41 <div id="nav"> 42 <ul><li> 43 <a href="luajit.html">LuaJIT</a> 44 <ul><li> 45 <a href="http://luajit.org/download.html">Download <span class="ext">»</span></a> 46 </li><li> 47 <a href="install.html">Installation</a> 48 </li><li> 49 <a class="current" href="running.html">Running</a> 50 </li></ul> 51 </li><li> 52 <a href="extensions.html">Extensions</a> 53 <ul><li> 54 <a href="ext_ffi.html">FFI Library</a> 55 <ul><li> 56 <a href="ext_ffi_tutorial.html">FFI Tutorial</a> 57 </li><li> 58 <a href="ext_ffi_api.html">ffi.* API</a> 59 </li><li> 60 <a href="ext_ffi_semantics.html">FFI Semantics</a> 61 </li></ul> 62 </li><li> 63 <a href="ext_jit.html">jit.* Library</a> 64 </li><li> 65 <a href="ext_c_api.html">Lua/C API</a> 66 </li><li> 67 <a href="ext_profiler.html">Profiler</a> 68 </li></ul> 69 </li><li> 70 <a href="status.html">Status</a> 71 <ul><li> 72 <a href="changes.html">Changes</a> 73 </li></ul> 74 </li><li> 75 <a href="faq.html">FAQ</a> 76 </li><li> 77 <a href="http://luajit.org/performance.html">Performance <span class="ext">»</span></a> 78 </li><li> 79 <a href="http://wiki.luajit.org/">Wiki <span class="ext">»</span></a> 80 </li><li> 81 <a href="http://luajit.org/list.html">Mailing List <span class="ext">»</span></a> 82 </li></ul> 83 </div> 84 <div id="main"> 85 <p> 86 LuaJIT has only a single stand-alone executable, called <tt>luajit</tt> on 87 POSIX systems or <tt>luajit.exe</tt> on Windows. It can be used to run simple 88 Lua statements or whole Lua applications from the command line. It has an 89 interactive mode, too. 90 </p> 91 92 <h2 id="options">Command Line Options</h2> 93 <p> 94 The <tt>luajit</tt> stand-alone executable is just a slightly modified 95 version of the regular <tt>lua</tt> stand-alone executable. 96 It supports the same basic options, too. <tt>luajit -h</tt> 97 prints a short list of the available options. Please have a look at the 98 <a href="http://www.lua.org/manual/5.1/manual.html#6"><span class="ext">»</span> Lua manual</a> 99 for details. 100 </p> 101 <p> 102 LuaJIT has some additional options: 103 </p> 104 105 <h3 id="opt_b"><tt>-b[options] input output</tt></h3> 106 <p> 107 This option saves or lists bytecode. The following additional options 108 are accepted: 109 </p> 110 <ul> 111 <li><tt>-l</tt> — Only list bytecode.</li> 112 <li><tt>-s</tt> — Strip debug info (this is the default).</li> 113 <li><tt>-g</tt> — Keep debug info.</li> 114 <li><tt>-n name</tt> — Set module name (default: auto-detect from input name)</li> 115 <li><tt>-t type</tt> — Set output file type (default: auto-detect from output name).</li> 116 <li><tt>-a arch</tt> — Override architecture for object files (default: native).</li> 117 <li><tt>-o os</tt> — Override OS for object files (default: native).</li> 118 <li><tt>-e chunk</tt> — Use chunk string as input.</li> 119 <li><tt>-</tt> (a single minus sign) — Use stdin as input and/or stdout as output.</li> 120 </ul> 121 <p> 122 The output file type is auto-detected from the extension of the output 123 file name: 124 </p> 125 <ul> 126 <li><tt>c</tt> — C source file, exported bytecode data.</li> 127 <li><tt>h</tt> — C header file, static bytecode data.</li> 128 <li><tt>obj</tt> or <tt>o</tt> — Object file, exported bytecode data 129 (OS- and architecture-specific).</li> 130 <li><tt>raw</tt> or any other extension — Raw bytecode file (portable). 131 </ul> 132 <p> 133 Notes: 134 </p> 135 <ul> 136 <li>See also <a href="extensions.html#string_dump">string.dump()</a> 137 for information on bytecode portability and compatibility.</li> 138 <li>A file in raw bytecode format is auto-detected and can be loaded like 139 any Lua source file. E.g. directly from the command line or with 140 <tt>loadfile()</tt>, <tt>dofile()</tt> etc.</li> 141 <li>To statically embed the bytecode of a module in your application, 142 generate an object file and just link it with your application.</li> 143 <li>On most ELF-based systems (e.g. Linux) you need to explicitly export the 144 global symbols when linking your application, e.g. with: <tt>-Wl,-E</tt></li> 145 <li><tt>require()</tt> tries to load embedded bytecode data from exported 146 symbols (in <tt>*.exe</tt> or <tt>lua51.dll</tt> on Windows) and from 147 shared libraries in <tt>package.cpath</tt>.</li> 148 </ul> 149 <p> 150 Typical usage examples: 151 </p> 152 <pre class="code"> 153 luajit -b test.lua test.out # Save bytecode to test.out 154 luajit -bg test.lua test.out # Keep debug info 155 luajit -be "print('hello world')" test.out # Save cmdline script 156 157 luajit -bl test.lua # List to stdout 158 luajit -bl test.lua test.txt # List to test.txt 159 luajit -ble "print('hello world')" # List cmdline script 160 161 luajit -b test.lua test.obj # Generate object file 162 # Link test.obj with your application and load it with require("test") 163 </pre> 164 165 <h3 id="opt_j"><tt>-j cmd[=arg[,arg...]]</tt></h3> 166 <p> 167 This option performs a LuaJIT control command or activates one of the 168 loadable extension modules. The command is first looked up in the 169 <tt>jit.*</tt> library. If no matching function is found, a module 170 named <tt>jit.<cmd></tt> is loaded and the <tt>start()</tt> 171 function of the module is called with the specified arguments (if 172 any). The space between <tt>-j</tt> and <tt>cmd</tt> is optional. 173 </p> 174 <p> 175 Here are the available LuaJIT control commands: 176 </p> 177 <ul> 178 <li id="j_on"><tt>-jon</tt> — Turns the JIT compiler on (default).</li> 179 <li id="j_off"><tt>-joff</tt> — Turns the JIT compiler off (only use the interpreter).</li> 180 <li id="j_flush"><tt>-jflush</tt> — Flushes the whole cache of compiled code.</li> 181 <li id="j_v"><tt>-jv</tt> — Shows verbose information about the progress of the JIT compiler.</li> 182 <li id="j_dump"><tt>-jdump</tt> — Dumps the code and structures used in various compiler stages.</li> 183 <li id="j_p"><tt>-jp</tt> — Start the <a href="ext_profiler.html">integrated profiler</a>.</li> 184 </ul> 185 <p> 186 The <tt>-jv</tt> and <tt>-jdump</tt> commands are extension modules 187 written in Lua. They are mainly used for debugging the JIT compiler 188 itself. For a description of their options and output format, please 189 read the comment block at the start of their source. 190 They can be found in the <tt>lib</tt> directory of the source 191 distribution or installed under the <tt>jit</tt> directory. By default 192 this is <tt>/usr/local/share/luajit-2.0.4/jit</tt> on POSIX 193 systems. 194 </p> 195 196 <h3 id="opt_O"><tt>-O[level]</tt><br> 197 <tt>-O[+]flag</tt> <tt>-O-flag</tt><br> 198 <tt>-Oparam=value</tt></h3> 199 <p> 200 This options allows fine-tuned control of the optimizations used by 201 the JIT compiler. This is mainly intended for debugging LuaJIT itself. 202 Please note that the JIT compiler is extremely fast (we are talking 203 about the microsecond to millisecond range). Disabling optimizations 204 doesn't have any visible impact on its overhead, but usually generates 205 code that runs slower. 206 </p> 207 <p> 208 The first form sets an optimization level — this enables a 209 specific mix of optimization flags. <tt>-O0</tt> turns off all 210 optimizations and higher numbers enable more optimizations. Omitting 211 the level (i.e. just <tt>-O</tt>) sets the default optimization level, 212 which is <tt>-O3</tt> in the current version. 213 </p> 214 <p> 215 The second form adds or removes individual optimization flags. 216 The third form sets a parameter for the VM or the JIT compiler 217 to a specific value. 218 </p> 219 <p> 220 You can either use this option multiple times (like <tt>-Ocse 221 -O-dce -Ohotloop=10</tt>) or separate several settings with a comma 222 (like <tt>-O+cse,-dce,hotloop=10</tt>). The settings are applied from 223 left to right and later settings override earlier ones. You can freely 224 mix the three forms, but note that setting an optimization level 225 overrides all earlier flags. 226 </p> 227 <p> 228 Here are the available flags and at what optimization levels they 229 are enabled: 230 </p> 231 <table class="opt"> 232 <tr class="opthead"> 233 <td class="flag_name">Flag</td> 234 <td class="flag_level">-O1</td> 235 <td class="flag_level">-O2</td> 236 <td class="flag_level">-O3</td> 237 <td class="flag_desc"> </td> 238 </tr> 239 <tr class="odd separate"> 240 <td class="flag_name">fold</td><td class="flag_level">•</td><td class="flag_level">•</td><td class="flag_level">•</td><td class="flag_desc">Constant Folding, Simplifications and Reassociation</td></tr> 241 <tr class="even"> 242 <td class="flag_name">cse</td><td class="flag_level">•</td><td class="flag_level">•</td><td class="flag_level">•</td><td class="flag_desc">Common-Subexpression Elimination</td></tr> 243 <tr class="odd"> 244 <td class="flag_name">dce</td><td class="flag_level">•</td><td class="flag_level">•</td><td class="flag_level">•</td><td class="flag_desc">Dead-Code Elimination</td></tr> 245 <tr class="even"> 246 <td class="flag_name">narrow</td><td class="flag_level"> </td><td class="flag_level">•</td><td class="flag_level">•</td><td class="flag_desc">Narrowing of numbers to integers</td></tr> 247 <tr class="odd"> 248 <td class="flag_name">loop</td><td class="flag_level"> </td><td class="flag_level">•</td><td class="flag_level">•</td><td class="flag_desc">Loop Optimizations (code hoisting)</td></tr> 249 <tr class="even"> 250 <td class="flag_name">fwd</td><td class="flag_level"> </td><td class="flag_level"> </td><td class="flag_level">•</td><td class="flag_desc">Load Forwarding (L2L) and Store Forwarding (S2L)</td></tr> 251 <tr class="odd"> 252 <td class="flag_name">dse</td><td class="flag_level"> </td><td class="flag_level"> </td><td class="flag_level">•</td><td class="flag_desc">Dead-Store Elimination</td></tr> 253 <tr class="even"> 254 <td class="flag_name">abc</td><td class="flag_level"> </td><td class="flag_level"> </td><td class="flag_level">•</td><td class="flag_desc">Array Bounds Check Elimination</td></tr> 255 <tr class="odd"> 256 <td class="flag_name">sink</td><td class="flag_level"> </td><td class="flag_level"> </td><td class="flag_level">•</td><td class="flag_desc">Allocation/Store Sinking</td></tr> 257 <tr class="even"> 258 <td class="flag_name">fuse</td><td class="flag_level"> </td><td class="flag_level"> </td><td class="flag_level">•</td><td class="flag_desc">Fusion of operands into instructions</td></tr> 259 </table> 260 <p> 261 Here are the parameters and their default settings: 262 </p> 263 <table class="opt"> 264 <tr class="opthead"> 265 <td class="param_name">Parameter</td> 266 <td class="param_default">Default</td> 267 <td class="param_desc"> </td> 268 </tr> 269 <tr class="odd separate"> 270 <td class="param_name">maxtrace</td><td class="param_default">1000</td><td class="param_desc">Max. number of traces in the cache</td></tr> 271 <tr class="even"> 272 <td class="param_name">maxrecord</td><td class="param_default">4000</td><td class="param_desc">Max. number of recorded IR instructions</td></tr> 273 <tr class="odd"> 274 <td class="param_name">maxirconst</td><td class="param_default">500</td><td class="param_desc">Max. number of IR constants of a trace</td></tr> 275 <tr class="even"> 276 <td class="param_name">maxside</td><td class="param_default">100</td><td class="param_desc">Max. number of side traces of a root trace</td></tr> 277 <tr class="odd"> 278 <td class="param_name">maxsnap</td><td class="param_default">500</td><td class="param_desc">Max. number of snapshots for a trace</td></tr> 279 <tr class="even separate"> 280 <td class="param_name">hotloop</td><td class="param_default">56</td><td class="param_desc">Number of iterations to detect a hot loop or hot call</td></tr> 281 <tr class="odd"> 282 <td class="param_name">hotexit</td><td class="param_default">10</td><td class="param_desc">Number of taken exits to start a side trace</td></tr> 283 <tr class="even"> 284 <td class="param_name">tryside</td><td class="param_default">4</td><td class="param_desc">Number of attempts to compile a side trace</td></tr> 285 <tr class="odd separate"> 286 <td class="param_name">instunroll</td><td class="param_default">4</td><td class="param_desc">Max. unroll factor for instable loops</td></tr> 287 <tr class="even"> 288 <td class="param_name">loopunroll</td><td class="param_default">15</td><td class="param_desc">Max. unroll factor for loop ops in side traces</td></tr> 289 <tr class="odd"> 290 <td class="param_name">callunroll</td><td class="param_default">3</td><td class="param_desc">Max. unroll factor for pseudo-recursive calls</td></tr> 291 <tr class="even"> 292 <td class="param_name">recunroll</td><td class="param_default">2</td><td class="param_desc">Min. unroll factor for true recursion</td></tr> 293 <tr class="odd separate"> 294 <td class="param_name">sizemcode</td><td class="param_default">32</td><td class="param_desc">Size of each machine code area in KBytes (Windows: 64K)</td></tr> 295 <tr class="even"> 296 <td class="param_name">maxmcode</td><td class="param_default">512</td><td class="param_desc">Max. total size of all machine code areas in KBytes</td></tr> 297 </table> 298 <br class="flush"> 299 </div> 300 <div id="foot"> 301 <hr class="hide"> 302 Copyright © 2005-2016 Mike Pall 303 <span class="noprint"> 304 · 305 <a href="contact.html">Contact</a> 306 </span> 307 </div> 308 </body> 309 </html>