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Strip comments and inline ids onto h*

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James Gregory 2013-12-30 15:11:04 +11:00
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01-03.html
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@ -10,16 +10,9 @@
<meta name="vspubdate" content="07/01/97" />
<meta name="vscategory" content="Web and Software Development: Game Development,Web and Software Development: Graphics and Multimedia Development" />
<title>Michael Abrash's Graphics Programming Black Book Special Edition: The Best Optimizer Is between Your Ears</title><!-- HEADER -->
<!-- Empty Reference Subhead -->
<!--ISBN=1576101746//-->
<!--TITLE=Michael Abrash's Graphics Programming Black Book Special Edition//-->
<!--AUTHOR=Michael Abrash//-->
<!--PUBLISHER=The Coriolis Group, Inc.//-->
<title>Michael Abrash's Graphics Programming Black Book Special Edition: The Best Optimizer Is between Your Ears</title>
<meta name="chapter" content="01" />
<meta name="pages" content="010-013" />
<!--UNASSIGNED1//-->
<!--UNASSIGNED2//-->
</head>
<body>
@ -165,7 +158,7 @@
</tr>
</table>
<p><b>LISTING 1.2 L1-2.C</b></p><!-- CODE //-->
<p><b>LISTING 1.2 L1-2.C</b></p>
<pre>
/*
* Program to calculate the 16-bit checksum of the stream of bytes
@ -199,9 +192,9 @@ main(int argc, char *argv[]) {
printf(&ldquo;The checksum is: %u\n&rdquo;, Checksum);
exit(0);
}
</pre><!-- END CODE //-->
</pre>
<p><b>LISTING 1.3 L1-3.ASM</b></p><!-- CODE //-->
<p><b>LISTING 1.3 L1-3.ASM</b></p>
<pre>
; Assembler subroutine to perform a 16-bit checksum on the file
; opened on the passed-in handle. Stores the result in the
@ -267,13 +260,13 @@ Done:
ret
_ChecksumFileendp
end
</pre><!-- END CODE //-->
</pre>
<p>The lesson is clear: Optimization makes code faster, but without proper design, optimization just creates fast slow code.</p>
<p>Well, then, how are we going to improve our design? Before we can do that, we have to understand what&rsquo;s wrong with the current design.</p>
<h4 align="left"><a id="Heading9"></a>Know the Territory</h4>
<h4 align="left" id="Heading9">Know the Territory</h4>
<p>Just why is Listing 1.1 so slow? In a word: overhead. The C library implements the <b>read()</b> function by calling DOS to read the desired number of bytes. (I figured this out by watching the code execute with a debugger, but you can buy library source code from both Microsoft and Borland.) That means that Listing 1.1 (and Listing 1.3 as well) executes one DOS function per byte processed&mdash;and DOS functions, especially this one, come with a lot of overhead.</p>
@ -302,10 +295,6 @@ _ChecksumFileendp
<div align="center">
Graphics Programming Black Book &copy; 2001 Michael Abrash
</div><!-- all of the reference materials (books) have the footer and subfoot reveresed -->
<!-- reference_subfoot = footer -->
<!-- reference_footer = subfoot -->
<!-- BEGIN SUB FOOTER -->
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</div>
</body>
</html>