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| author | alk3pInjection <webmaster@raspii.tech> | 2024-02-04 16:16:35 +0800 |
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| committer | alk3pInjection <webmaster@raspii.tech> | 2024-02-04 16:16:35 +0800 |
| commit | abdaadbcae30fe0c9a66c7516798279fdfd97750 (patch) | |
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diff --git a/share/doc/gfortran/Bitwise-logical-operators.html b/share/doc/gfortran/Bitwise-logical-operators.html new file mode 100644 index 0000000..57693d6 --- /dev/null +++ b/share/doc/gfortran/Bitwise-logical-operators.html @@ -0,0 +1,118 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- Copyright (C) 1999-2023 Free Software Foundation, Inc. + +Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.3 or +any later version published by the Free Software Foundation; with the +Invariant Sections being "Funding Free Software", the Front-Cover +Texts being (a) (see below), and with the Back-Cover Texts being (b) +(see below). A copy of the license is included in the section entitled +"GNU Free Documentation License". + +(a) The FSF's Front-Cover Text is: + +A GNU Manual + +(b) The FSF's Back-Cover Text is: + +You have freedom to copy and modify this GNU Manual, like GNU + software. Copies published by the Free Software Foundation raise + funds for GNU development. --> +<!-- Created by GNU Texinfo 5.1, http://www.gnu.org/software/texinfo/ --> +<head> +<title>The GNU Fortran Compiler: Bitwise logical operators</title> + +<meta name="description" content="The GNU Fortran Compiler: Bitwise logical operators"> +<meta name="keywords" content="The GNU Fortran Compiler: Bitwise logical operators"> +<meta name="resource-type" content="document"> +<meta name="distribution" content="global"> +<meta name="Generator" content="makeinfo"> +<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> +<link href="index.html#Top" rel="start" title="Top"> +<link href="Option-Index.html#Option-Index" rel="index" title="Option Index"> +<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> +<link href="Extensions-implemented-in-GNU-Fortran.html#Extensions-implemented-in-GNU-Fortran" rel="up" title="Extensions implemented in GNU Fortran"> +<link href="Extended-I_002fO-specifiers.html#Extended-I_002fO-specifiers" rel="next" title="Extended I/O specifiers"> +<link href="_002eXOR_002e-operator.html#g_t_002eXOR_002e-operator" rel="previous" title=".XOR. operator"> +<style type="text/css"> +<!-- +a.summary-letter {text-decoration: none} +blockquote.smallquotation {font-size: smaller} +div.display {margin-left: 3.2em} +div.example {margin-left: 3.2em} +div.indentedblock {margin-left: 3.2em} +div.lisp {margin-left: 3.2em} +div.smalldisplay {margin-left: 3.2em} +div.smallexample {margin-left: 3.2em} +div.smallindentedblock {margin-left: 3.2em; font-size: smaller} +div.smalllisp {margin-left: 3.2em} +kbd {font-style:oblique} +pre.display {font-family: inherit} +pre.format {font-family: inherit} +pre.menu-comment {font-family: serif} +pre.menu-preformatted {font-family: serif} +pre.smalldisplay {font-family: inherit; font-size: smaller} +pre.smallexample {font-size: smaller} +pre.smallformat {font-family: inherit; font-size: smaller} +pre.smalllisp {font-size: smaller} +span.nocodebreak {white-space:nowrap} +span.nolinebreak {white-space:nowrap} +span.roman {font-family:serif; font-weight:normal} +span.sansserif {font-family:sans-serif; font-weight:normal} +ul.no-bullet {list-style: none} +--> +</style> + + +</head> + +<body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000"> +<a name="Bitwise-logical-operators"></a> +<div class="header"> +<p> +Next: <a href="Extended-I_002fO-specifiers.html#Extended-I_002fO-specifiers" accesskey="n" rel="next">Extended I/O specifiers</a>, Previous: <a href="_002eXOR_002e-operator.html#g_t_002eXOR_002e-operator" accesskey="p" rel="previous">.XOR. operator</a>, Up: <a href="Extensions-implemented-in-GNU-Fortran.html#Extensions-implemented-in-GNU-Fortran" accesskey="u" rel="up">Extensions implemented in GNU Fortran</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p> +</div> +<hr> +<a name="Bitwise-logical-operators-1"></a> +<h4 class="subsection">5.1.31 Bitwise logical operators</h4> +<a name="index-logical_002c-bitwise"></a> + +<p>With <samp>-fdec</samp>, GNU Fortran relaxes the type constraints on +logical operators to allow integer operands, and performs the corresponding +bitwise operation instead. This flag is for compatibility only, and should be +avoided in new code. Consider: +</p> +<div class="smallexample"> +<pre class="smallexample"> INTEGER :: i, j + i = z'33' + j = z'cc' + print *, i .AND. j +</pre></div> + +<p>In this example, compiled with <samp>-fdec</samp>, GNU Fortran will +replace the <code>.AND.</code> operation with a call to the intrinsic +<code><a href="IAND.html#IAND">IAND</a></code> function, yielding the bitwise-and of <code>i</code> and <code>j</code>. +</p> +<p>Note that this conversion will occur if at least one operand is of integral +type. As a result, a logical operand will be converted to an integer when the +other operand is an integer in a logical operation. In this case, +<code>.TRUE.</code> is converted to <code>1</code> and <code>.FALSE.</code> to <code>0</code>. +</p> +<p>Here is the mapping of logical operator to bitwise intrinsic used with +<samp>-fdec</samp>: +</p> +<table> +<thead><tr><th width="25%">Operator</th><th width="25%">Intrinsic</th><th width="50%">Bitwise operation</th></tr></thead> +<tr><td width="25%"><code>.NOT.</code></td><td width="25%"><code><a href="NOT.html#NOT">NOT</a></code></td><td width="50%">complement</td></tr> +<tr><td width="25%"><code>.AND.</code></td><td width="25%"><code><a href="IAND.html#IAND">IAND</a></code></td><td width="50%">intersection</td></tr> +<tr><td width="25%"><code>.OR.</code></td><td width="25%"><code><a href="IOR.html#IOR">IOR</a></code></td><td width="50%">union</td></tr> +<tr><td width="25%"><code>.NEQV.</code></td><td width="25%"><code><a href="IEOR.html#IEOR">IEOR</a></code></td><td width="50%">exclusive or</td></tr> +<tr><td width="25%"><code>.EQV.</code></td><td width="25%"><code><a href="NOT.html#NOT">NOT</a>(<a href="IEOR.html#IEOR">IEOR</a>)</code></td><td width="50%">complement of exclusive or</td></tr> +</table> + + + + +</body> +</html> |