You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

126 lines
6.5 KiB
HTML

<html lang="en">
<head>
<title>Paired-Single Built-in Functions - Using the GNU Compiler Collection (GCC)</title>
<meta http-equiv="Content-Type" content="text/html">
<meta name="description" content="Using the GNU Compiler Collection (GCC)">
<meta name="generator" content="makeinfo 4.13">
<link title="Top" rel="start" href="index.html#Top">
<link rel="up" href="MIPS-Loongson-Built_002din-Functions.html#MIPS-Loongson-Built_002din-Functions" title="MIPS Loongson Built-in Functions">
<link rel="prev" href="Paired_002dSingle-Arithmetic.html#Paired_002dSingle-Arithmetic" title="Paired-Single Arithmetic">
<link rel="next" href="MIPS_002d3D-Built_002din-Functions.html#MIPS_002d3D-Built_002din-Functions" title="MIPS-3D Built-in Functions">
<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage">
<!--
Copyright (C) 1988-2015 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.-->
<meta http-equiv="Content-Style-Type" content="text/css">
<style type="text/css"><!--
pre.display { font-family:inherit }
pre.format { font-family:inherit }
pre.smalldisplay { font-family:inherit; font-size:smaller }
pre.smallformat { font-family:inherit; font-size:smaller }
pre.smallexample { font-size:smaller }
pre.smalllisp { font-size:smaller }
span.sc { font-variant:small-caps }
span.roman { font-family:serif; font-weight:normal; }
span.sansserif { font-family:sans-serif; font-weight:normal; }
--></style>
</head>
<body>
<div class="node">
<a name="Paired-Single-Built-in-Functions"></a>
<a name="Paired_002dSingle-Built_002din-Functions"></a>
<p>
Next:&nbsp;<a rel="next" accesskey="n" href="MIPS_002d3D-Built_002din-Functions.html#MIPS_002d3D-Built_002din-Functions">MIPS-3D Built-in Functions</a>,
Previous:&nbsp;<a rel="previous" accesskey="p" href="Paired_002dSingle-Arithmetic.html#Paired_002dSingle-Arithmetic">Paired-Single Arithmetic</a>,
Up:&nbsp;<a rel="up" accesskey="u" href="MIPS-Loongson-Built_002din-Functions.html#MIPS-Loongson-Built_002din-Functions">MIPS Loongson Built-in Functions</a>
<hr>
</div>
<h5 class="subsubsection">6.58.14.2 Paired-Single Built-in Functions</h5>
<p>The following paired-single functions map directly to a particular
MIPS instruction. Please refer to the architecture specification
for details on what each instruction does.
<dl>
<dt><code>v2sf __builtin_mips_pll_ps (v2sf, v2sf)</code><dd>Pair lower lower (<code>pll.ps</code>).
<br><dt><code>v2sf __builtin_mips_pul_ps (v2sf, v2sf)</code><dd>Pair upper lower (<code>pul.ps</code>).
<br><dt><code>v2sf __builtin_mips_plu_ps (v2sf, v2sf)</code><dd>Pair lower upper (<code>plu.ps</code>).
<br><dt><code>v2sf __builtin_mips_puu_ps (v2sf, v2sf)</code><dd>Pair upper upper (<code>puu.ps</code>).
<br><dt><code>v2sf __builtin_mips_cvt_ps_s (float, float)</code><dd>Convert pair to paired single (<code>cvt.ps.s</code>).
<br><dt><code>float __builtin_mips_cvt_s_pl (v2sf)</code><dd>Convert pair lower to single (<code>cvt.s.pl</code>).
<br><dt><code>float __builtin_mips_cvt_s_pu (v2sf)</code><dd>Convert pair upper to single (<code>cvt.s.pu</code>).
<br><dt><code>v2sf __builtin_mips_abs_ps (v2sf)</code><dd>Absolute value (<code>abs.ps</code>).
<br><dt><code>v2sf __builtin_mips_alnv_ps (v2sf, v2sf, int)</code><dd>Align variable (<code>alnv.ps</code>).
<p><em>Note:</em> The value of the third parameter must be 0 or 4
modulo 8, otherwise the result is unpredictable. Please read the
instruction description for details.
</dl>
<p>The following multi-instruction functions are also available.
In each case, <var>cond</var> can be any of the 16 floating-point conditions:
<code>f</code>, <code>un</code>, <code>eq</code>, <code>ueq</code>, <code>olt</code>, <code>ult</code>,
<code>ole</code>, <code>ule</code>, <code>sf</code>, <code>ngle</code>, <code>seq</code>, <code>ngl</code>,
<code>lt</code>, <code>nge</code>, <code>le</code> or <code>ngt</code>.
<dl>
<dt><code>v2sf __builtin_mips_movt_c_</code><var>cond</var><code>_ps (v2sf </code><var>a</var><code>, v2sf </code><var>b</var><code>, v2sf </code><var>c</var><code>, v2sf </code><var>d</var><code>)</code><dt><code>v2sf __builtin_mips_movf_c_</code><var>cond</var><code>_ps (v2sf </code><var>a</var><code>, v2sf </code><var>b</var><code>, v2sf </code><var>c</var><code>, v2sf </code><var>d</var><code>)</code><dd>Conditional move based on floating-point comparison (<code>c.</code><var>cond</var><code>.ps</code>,
<code>movt.ps</code>/<code>movf.ps</code>).
<p>The <code>movt</code> functions return the value <var>x</var> computed by:
<pre class="smallexample"> c.<var>cond</var>.ps <var>cc</var>,<var>a</var>,<var>b</var>
mov.ps <var>x</var>,<var>c</var>
movt.ps <var>x</var>,<var>d</var>,<var>cc</var>
</pre>
<p>The <code>movf</code> functions are similar but use <code>movf.ps</code> instead
of <code>movt.ps</code>.
<br><dt><code>int __builtin_mips_upper_c_</code><var>cond</var><code>_ps (v2sf </code><var>a</var><code>, v2sf </code><var>b</var><code>)</code><dt><code>int __builtin_mips_lower_c_</code><var>cond</var><code>_ps (v2sf </code><var>a</var><code>, v2sf </code><var>b</var><code>)</code><dd>Comparison of two paired-single values (<code>c.</code><var>cond</var><code>.ps</code>,
<code>bc1t</code>/<code>bc1f</code>).
<p>These functions compare <var>a</var> and <var>b</var> using <code>c.</code><var>cond</var><code>.ps</code>
and return either the upper or lower half of the result. For example:
<pre class="smallexample"> v2sf a, b;
if (__builtin_mips_upper_c_eq_ps (a, b))
upper_halves_are_equal ();
else
upper_halves_are_unequal ();
if (__builtin_mips_lower_c_eq_ps (a, b))
lower_halves_are_equal ();
else
lower_halves_are_unequal ();
</pre>
</dl>
</body></html>