<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="generator" content="TempleOS V5.03">
<meta name="viewport" content="width=device-width">
<link rel="stylesheet" href="/style/templeos.css">
<script src="/script/templeos.js"></script>
<style type="text/css">
.cF0{color:#000000;background-color:#ffffff;}
.cF1{color:#0000aa;background-color:#ffffff;}
.cF2{color:#00aa00;background-color:#ffffff;}
.cF3{color:#00aaaa;background-color:#ffffff;}
.cF4{color:#aa0000;background-color:#ffffff;}
.cF5{color:#aa00aa;background-color:#ffffff;}
.cF6{color:#aa5500;background-color:#ffffff;}
.cF7{color:#aaaaaa;background-color:#ffffff;}
.cF8{color:#555555;background-color:#ffffff;}
.cF9{color:#5555ff;background-color:#ffffff;}
.cFA{color:#55ff55;background-color:#ffffff;}
.cFB{color:#55ffff;background-color:#ffffff;}
.cFC{color:#ff5555;background-color:#ffffff;}
.cFD{color:#ff55ff;background-color:#ffffff;}
.cFE{color:#ffff55;background-color:#ffffff;}
.cFF{color:#ffffff;background-color:#ffffff;}
</style>
</head>
<body>
<pre style="font-family: courier, monospace; font-size: 10pt;">
<a name="l1"></a><span class=cFA>/* Graphics Not Rendered in HTML */</span><span class=cF0>
<a name="l2"></a>
<a name="l3"></a>
<a name="l4"></a>
<a name="l5"></a>
<a name="l6"></a>
<a name="l7"></a>
<a name="l8"></a>
<a name="l9"></a>
<a name="l10"></a>
<a name="l11"></a>
<a name="l12"></a>
<a name="l13"></a>
<a name="l14"></a>
<a name="l15"></a>
<a name="l16"></a>
<a name="l17"></a>
<a name="l18"></a>
<a name="l19"></a>
<a name="l20"></a>
<a name="l21"></a>
<a name="l22"></a>
<a name="l23"></a>
<a name="l24"></a>
<a name="l25"></a>
<a name="l26"></a>
<a name="l27"></a>
<a name="l28"></a>There is a symbol (hash) table for each task. When a sym is not found, the
<a name="l29"></a>parent task's sym table is checked. All tasks chain back to the </span><span class=cF2>Adam</span><span class=cF0> task.
<a name="l30"></a>
<a name="l31"></a>TempleOS sym tables are implemented with an array of linked-lists. A num is
<a name="l32"></a>generated from a string by </span><a href="/Wb/Kernel/KHashA.HC#l254"><span class=cF4>HashStr</span></a><span class=cF0>() to index into the array of linked-lists.
<a name="l33"></a>Multiple strings can generate the same num, so linked-lists are built. Newer
<a name="l34"></a>entries overshadow older ones.
<a name="l35"></a>
<a name="l36"></a>There are various types of entries. See </span><a href="/Wb/Kernel/KernelA.HH#l686"><span class=cF4>Hash Entry Types</span></a><span class=cF0>.
<a name="l37"></a>
<a name="l38"></a></span><span class=cF5>Symbol Look-up</span><span class=cF0> (Used many places including the </span><a href="/Wb/Compiler/Lex.HC#l499"><span class=cF4>JIT Compiler</span></a><span class=cF0> and </span><a href="/Wb/Kernel/KLoad.HC#l19"><span class=cF4>Loader</span></a><span class=cF0>.)
<a name="l39"></a>1) Symbol name is </span><a href="/Wb/Kernel/KHashA.HC#l4"><span class=cF4>hashed</span></a><span class=cF0> by adding and shifting the ASCII of all chars.
<a name="l40"></a>2) </span><a href="/Wb/Kernel/KernelA.HH#l647"><span class=cF4>hash table</span></a><span class=cF0>->body[] array is indexed.
<a name="l41"></a>3) Linked-lst is traversed until match of text and type of entry.
<a name="l42"></a>4) If not found, </span><a href="/Wb/Kernel/KernelA.HH#l647"><span class=cF4>hash table</span></a><span class=cF0>->next table is searched.
<a name="l43"></a>
<a name="l44"></a>Duplicate entries are allowed -- they overshadow old entries.
<a name="l45"></a>
<a name="l46"></a></span><span class=cF5>Address-to-Symbol Look-up</span><span class=cF0> (Slow because not important. We could use trees.)
<a name="l47"></a>1) FunSeg Cache is </span><a href="/Wb/Kernel/FunSeg.HC#l114"><span class=cF4>scanned</span></a><span class=cF0>.
<a name="l48"></a>2) Hash Tables are </span><a href="/Wb/Kernel/FunSeg.HC#l54"><span class=cF4>scanned</span></a><span class=cF0>.
</span></pre></body>
</html>