HCoop / hcoop / debian / mlton.git / blame
| Commit | Line | Data |
|---|---|---|
| 7f918cf1 CE |
1 | <!DOCTYPE html>\r |
| 2 | <html lang="en">\r | |
| 3 | <head>\r | |
| 4 | <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">\r | |
| 5 | <meta name="generator" content="AsciiDoc 8.6.9">\r | |
| 6 | <title>DeadCode</title>\r | |
| 7 | <link rel="stylesheet" href="./asciidoc.css" type="text/css">\r | |
| 8 | <link rel="stylesheet" href="./pygments.css" type="text/css">\r | |
| 9 | \r | |
| 10 | \r | |
| 11 | <script type="text/javascript" src="./asciidoc.js"></script>\r | |
| 12 | <script type="text/javascript">\r | |
| 13 | /*<![CDATA[*/\r | |
| 14 | asciidoc.install();\r | |
| 15 | /*]]>*/\r | |
| 16 | </script>\r | |
| 17 | <link rel="stylesheet" href="./mlton.css" type="text/css">\r | |
| 18 | </head>\r | |
| 19 | <body class="article">\r | |
| 20 | <div id="banner">\r | |
| 21 | <div id="banner-home">\r | |
| 22 | <a href="./Home">MLton 20180207</a>\r | |
| 23 | </div>\r | |
| 24 | </div>\r | |
| 25 | <div id="header">\r | |
| 26 | <h1>DeadCode</h1>\r | |
| 27 | </div>\r | |
| 28 | <div id="content">\r | |
| 29 | <div id="preamble">\r | |
| 30 | <div class="sectionbody">\r | |
| 31 | <div class="paragraph"><p><a href="DeadCode">DeadCode</a> is an optimization pass for the <a href="CoreML">CoreML</a>\r | |
| 32 | <a href="IntermediateLanguage">IntermediateLanguage</a>, invoked from <a href="CoreMLSimplify">CoreMLSimplify</a>.</p></div>\r | |
| 33 | </div>\r | |
| 34 | </div>\r | |
| 35 | <div class="sect1">\r | |
| 36 | <h2 id="_description">Description</h2>\r | |
| 37 | <div class="sectionbody">\r | |
| 38 | <div class="paragraph"><p>This pass eliminates declarations from the\r | |
| 39 | <a href="BasisLibrary">Basis Library</a> not needed by the user program.</p></div>\r | |
| 40 | </div>\r | |
| 41 | </div>\r | |
| 42 | <div class="sect1">\r | |
| 43 | <h2 id="_implementation">Implementation</h2>\r | |
| 44 | <div class="sectionbody">\r | |
| 45 | <div class="ulist"><ul>\r | |
| 46 | <li>\r | |
| 47 | <p>\r | |
| 48 | <a href="https://github.com/MLton/mlton/blob/master/mlton/core-ml/dead-code.sig"><span class="monospaced">dead-code.sig</span></a>\r | |
| 49 | </p>\r | |
| 50 | </li>\r | |
| 51 | <li>\r | |
| 52 | <p>\r | |
| 53 | <a href="https://github.com/MLton/mlton/blob/master/mlton/core-ml/dead-code.fun"><span class="monospaced">dead-code.fun</span></a>\r | |
| 54 | </p>\r | |
| 55 | </li>\r | |
| 56 | </ul></div>\r | |
| 57 | </div>\r | |
| 58 | </div>\r | |
| 59 | <div class="sect1">\r | |
| 60 | <h2 id="_details_and_notes">Details and Notes</h2>\r | |
| 61 | <div class="sectionbody">\r | |
| 62 | <div class="paragraph"><p>In order to compile small programs rapidly, a pass of dead code\r | |
| 63 | elimination is run in order to eliminate as much of the Basis Library\r | |
| 64 | as possible. The dead code elimination algorithm used is not safe in\r | |
| 65 | general, and only works because the Basis Library implementation has\r | |
| 66 | special properties:</p></div>\r | |
| 67 | <div class="ulist"><ul>\r | |
| 68 | <li>\r | |
| 69 | <p>\r | |
| 70 | it terminates\r | |
| 71 | </p>\r | |
| 72 | </li>\r | |
| 73 | <li>\r | |
| 74 | <p>\r | |
| 75 | it performs no I/O\r | |
| 76 | </p>\r | |
| 77 | </li>\r | |
| 78 | </ul></div>\r | |
| 79 | <div class="paragraph"><p>The dead code elimination includes the minimal set of\r | |
| 80 | declarations from the Basis Library so that there are no free\r | |
| 81 | variables in the user program (or remaining Basis Library\r | |
| 82 | implementation). It has a special hack to include all\r | |
| 83 | bindings of the form:</p></div>\r | |
| 84 | <div class="listingblock">\r | |
| 85 | <div class="content"><div class="highlight"><pre><span class="w"> </span><span class="k">val</span><span class="w"> </span><span class="p">_</span><span class="w"> </span><span class="p">=</span><span class="w"> </span><span class="p">...</span><span class="w"></span>\r | |
| 86 | </pre></div></div></div>\r | |
| 87 | <div class="paragraph"><p>There is an <a href="MLBasisAnnotations">ML Basis annotation</a>,\r | |
| 88 | <span class="monospaced">deadCode true</span>, that governs which code is subject to this unsafe\r | |
| 89 | dead-code elimination.</p></div>\r | |
| 90 | </div>\r | |
| 91 | </div>\r | |
| 92 | </div>\r | |
| 93 | <div id="footnotes"><hr></div>\r | |
| 94 | <div id="footer">\r | |
| 95 | <div id="footer-text">\r | |
| 96 | </div>\r | |
| 97 | <div id="footer-badges">\r | |
| 98 | </div>\r | |
| 99 | </div>\r | |
| 100 | </body>\r | |
| 101 | </html>\r |