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			5.4 KiB
		
	
	
	
		
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			129 lines
		
	
	
	
		
			5.4 KiB
		
	
	
	
		
			HTML
		
	
	
	
	
	
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								<!--
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								This file documents the GNU Assembler "as".
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								Copyright (C) 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000, 2001, 2002,
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								2006, 2007 Free Software Foundation, Inc.
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								Permission is granted to copy, distribute and/or modify this document
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								<p>
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								<a name="Infix-Ops"></a>Previous: <a rel="previous" accesskey="p" href="Prefix-Ops.html#Prefix-Ops">Prefix Ops</a>,
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								Up: <a rel="up" accesskey="u" href="Integer-Exprs.html#Integer-Exprs">Integer Exprs</a>
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								<hr><br>
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								</div>
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								<h4 class="subsection">6.2.4 Infix Operators</h4>
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								<p><a name="index-infix-operators-257"></a><a name="index-operators_002c-permitted-arguments-258"></a><dfn>Infix operators</dfn> take two arguments, one on either side.  Operators
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								have precedence, but operations with equal precedence are performed left
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								to right.  Apart from <code>+</code> or <span class="option">-</span>, both arguments must be
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								absolute, and the result is absolute.
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								     <ol type=1 start=1>
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								<a name="index-operator-precedence-259"></a><a name="index-precedence-of-operators-260"></a>
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								<li>Highest Precedence
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								          <dl>
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								<dt><code>*</code><dd><dfn>Multiplication</dfn>.
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								          <br><dt><code>/</code><dd><dfn>Division</dfn>.  Truncation is the same as the C operator <span class="samp">/</span>
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								          <br><dt><code>%</code><dd><dfn>Remainder</dfn>.
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								          <br><dt><code><<</code><dd><dfn>Shift Left</dfn>.  Same as the C operator <span class="samp"><<</span>.
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								          <br><dt><code>>></code><dd><dfn>Shift Right</dfn>.  Same as the C operator <span class="samp">>></span>. 
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								</dl>
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								     <li>Intermediate precedence
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								          <dl>
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								<dt><code>|</code><dd>
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								<dfn>Bitwise Inclusive Or</dfn>.
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								          <br><dt><code>&</code><dd><dfn>Bitwise And</dfn>.
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								          <br><dt><code>^</code><dd><dfn>Bitwise Exclusive Or</dfn>.
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								          <br><dt><code>!</code><dd><dfn>Bitwise Or Not</dfn>. 
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								</dl>
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								     <li>Low Precedence
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								<a name="index-addition_002c-permitted-arguments-261"></a>
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								<a name="index-plus_002c-permitted-arguments-262"></a>
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								<a name="index-arguments-for-addition-263"></a>
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								<dl><dt><code>+</code><dd><dfn>Addition</dfn>.  If either argument is absolute, the result has the section of
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								the other argument.  You may not add together arguments from different
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								sections.
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								          <p><a name="index-subtraction_002c-permitted-arguments-264"></a><a name="index-minus_002c-permitted-arguments-265"></a><a name="index-arguments-for-subtraction-266"></a><br><dt><code>-</code><dd><dfn>Subtraction</dfn>.  If the right argument is absolute, the
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								result has the section of the left argument. 
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								If both arguments are in the same section, the result is absolute. 
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								You may not subtract arguments from different sections. 
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								<!-- FIXME is there still something useful to say about undefined - undefined ? -->
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								          <p><a name="index-comparison-expressions-267"></a><a name="index-expressions_002c-comparison-268"></a><br><dt><code>==</code><dd><dfn>Is Equal To</dfn>
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								<br><dt><code><></code><dt><code>!=</code><dd><dfn>Is Not Equal To</dfn>
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								<br><dt><code><</code><dd><dfn>Is Less Than</dfn>
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								<br><dt><code>></code><dd><dfn>Is Greater Than</dfn>
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								<br><dt><code>>=</code><dd><dfn>Is Greater Than Or Equal To</dfn>
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								<br><dt><code><=</code><dd><dfn>Is Less Than Or Equal To</dfn>
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								          <p>The comparison operators can be used as infix operators.  A true results has a
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								value of -1 whereas a false result has a value of 0.   Note, these operators
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								perform signed comparisons. 
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								</dl>
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								     <li>Lowest Precedence
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								          <dl>
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								<dt><code>&&</code><dd><dfn>Logical And</dfn>.
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								          <br><dt><code>||</code><dd><dfn>Logical Or</dfn>.
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								          <p>These two logical operations can be used to combine the results of sub
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								expressions.  Note, unlike the comparison operators a true result returns a
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								value of 1 but a false results does still return 0.  Also note that the logical
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								or operator has a slightly lower precedence than logical and.
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								     </dl>
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								     </ol>
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								   <p>In short, it's only meaningful to add or subtract the <em>offsets</em> in an
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								address; you can only have a defined section in one of the two arguments.
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								   </body></html>
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