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Retidy, removing align=left from headings and empty paragraphs

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James Gregory 2013-12-30 15:37:13 +11:00
commit a96a114403
362 changed files with 8472 additions and 5040 deletions
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09-06.html
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@ -1,5 +1,4 @@
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
@ -19,17 +18,21 @@
<center>
<table border="1">
<tr>
<td><a href="09-05.html">Previous</a></td>
<td>
<a href="09-05.html">Previous</a>
</td>
<td><a href="index.html">Table of Contents</a></td>
<td>
<a href="index.html">Table of Contents</a>
</td>
<td><a href="09-07.html">Next</a></td>
<td>
<a href="09-07.html">Next</a>
</td>
</tr>
</table>
</center>
<p><br /></p>
<p><b>LISTING 9.5 L9-5.ASM</b></p>
<pre>
; Divides an arbitrarily long unsigned dividend by a 16-bit unsigned
@ -120,7 +123,7 @@ main() {
}
</pre>
<h4 align="left" id="Heading9">Sweet Spot Revisited</h4>
<h4 id="Heading9">Sweet Spot Revisited</h4>
<p>Way back in Volume 1, Number 1 of <i>PC TECHNIQUES</i>, (April/May 1990) I wrote the very first of that magazine&rsquo;s HAX (#1), which extolled the virtues of placing your most commonly-used automatic (stack-based) variables within the stack&rsquo;s &ldquo;sweet spot,&rdquo; the area between +127 to -128 bytes away from BP, the stack frame pointer. The reason was that the 8088 can store addressing displacements that fall within that range in a single byte; larger displacements require a full word of storage, increasing code size by a byte per instruction, and thereby slowing down performance due to increased instruction fetching time.</p>
@ -138,16 +141,20 @@ main() {
<p>In assembly, it&rsquo;s easy to control the organization of your stack frame. In C, however, you&rsquo;ll have to figure out the allocation scheme your compiler uses to allocate automatic variables, and declare automatics appropriately to produce the desired effect. It can be done: I did it in Turbo C some years back, and trimmed the size of a program (admittedly, a large one) by several K&mdash;not bad, when you consider that the &ldquo;sweet spot&rdquo; optimization is essentially free, with no code reorganization, change in logic, or heavy thinking involved.</p>
<p><br /></p>
<center>
<table border="1">
<tr>
<td><a href="09-05.html">Previous</a></td>
<td>
<a href="09-05.html">Previous</a>
</td>
<td><a href="index.html">Table of Contents</a></td>
<td>
<a href="index.html">Table of Contents</a>
</td>
<td><a href="09-07.html">Next</a></td>
<td>
<a href="09-07.html">Next</a>
</td>
</tr>
</table>
</center>