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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) | |
| tree | 00a54a6e25601e43876d03c1a4a12a749d4a914c /share/doc/gcc/Decimal-Float.html | |
https://developer.arm.com/downloads/-/arm-gnu-toolchain-downloads
Change-Id: I7303388733328cd98ab9aa3c30236db67f2e9e9c
Diffstat (limited to 'share/doc/gcc/Decimal-Float.html')
| -rw-r--r-- | share/doc/gcc/Decimal-Float.html | 139 |
1 files changed, 139 insertions, 0 deletions
diff --git a/share/doc/gcc/Decimal-Float.html b/share/doc/gcc/Decimal-Float.html new file mode 100644 index 0000000..c2c22bd --- /dev/null +++ b/share/doc/gcc/Decimal-Float.html @@ -0,0 +1,139 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- This file documents the use of the GNU compilers. + +Copyright (C) 1988-2023 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>Using the GNU Compiler Collection (GCC): Decimal Float</title> + +<meta name="description" content="Using the GNU Compiler Collection (GCC): Decimal Float"> +<meta name="keywords" content="Using the GNU Compiler Collection (GCC): Decimal Float"> +<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="Indices.html#Indices" rel="index" title="Indices"> +<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> +<link href="C-Extensions.html#C-Extensions" rel="up" title="C Extensions"> +<link href="Hex-Floats.html#Hex-Floats" rel="next" title="Hex Floats"> +<link href="Half_002dPrecision.html#Half_002dPrecision" rel="previous" title="Half-Precision"> +<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_US" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000"> +<a name="Decimal-Float"></a> +<div class="header"> +<p> +Next: <a href="Hex-Floats.html#Hex-Floats" accesskey="n" rel="next">Hex Floats</a>, Previous: <a href="Half_002dPrecision.html#Half_002dPrecision" accesskey="p" rel="previous">Half-Precision</a>, Up: <a href="C-Extensions.html#C-Extensions" accesskey="u" rel="up">C Extensions</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Indices.html#Indices" title="Index" rel="index">Index</a>]</p> +</div> +<hr> +<a name="Decimal-Floating-Types"></a> +<h3 class="section">6.14 Decimal Floating Types</h3> +<a name="index-decimal-floating-types"></a> +<a name="index-_005fDecimal32-data-type"></a> +<a name="index-_005fDecimal64-data-type"></a> +<a name="index-_005fDecimal128-data-type"></a> +<a name="index-df-integer-suffix"></a> +<a name="index-dd-integer-suffix"></a> +<a name="index-dl-integer-suffix"></a> +<a name="index-DF-integer-suffix"></a> +<a name="index-DD-integer-suffix"></a> +<a name="index-DL-integer-suffix"></a> + +<p>As an extension, GNU C supports decimal floating types as +defined in the N1312 draft of ISO/IEC WDTR24732. Support for decimal +floating types in GCC will evolve as the draft technical report changes. +Calling conventions for any target might also change. Not all targets +support decimal floating types. +</p> +<p>The decimal floating types are <code>_Decimal32</code>, <code>_Decimal64</code>, and +<code>_Decimal128</code>. They use a radix of ten, unlike the floating types +<code>float</code>, <code>double</code>, and <code>long double</code> whose radix is not +specified by the C standard but is usually two. +</p> +<p>Support for decimal floating types includes the arithmetic operators +add, subtract, multiply, divide; unary arithmetic operators; +relational operators; equality operators; and conversions to and from +integer and other floating types. Use a suffix ‘<samp>df</samp>’ or +‘<samp>DF</samp>’ in a literal constant of type <code>_Decimal32</code>, ‘<samp>dd</samp>’ +or ‘<samp>DD</samp>’ for <code>_Decimal64</code>, and ‘<samp>dl</samp>’ or ‘<samp>DL</samp>’ for +<code>_Decimal128</code>. +</p> +<p>GCC support of decimal float as specified by the draft technical report +is incomplete: +</p> +<ul> +<li> When the value of a decimal floating type cannot be represented in the +integer type to which it is being converted, the result is undefined +rather than the result value specified by the draft technical report. + +</li><li> GCC does not provide the C library functionality associated with +<samp>math.h</samp>, <samp>fenv.h</samp>, <samp>stdio.h</samp>, <samp>stdlib.h</samp>, and +<samp>wchar.h</samp>, which must come from a separate C library implementation. +Because of this the GNU C compiler does not define macro +<code>__STDC_DEC_FP__</code> to indicate that the implementation conforms to +the technical report. +</li></ul> + +<p>Types <code>_Decimal32</code>, <code>_Decimal64</code>, and <code>_Decimal128</code> +are supported by the DWARF debug information format. +</p> +<hr> +<div class="header"> +<p> +Next: <a href="Hex-Floats.html#Hex-Floats" accesskey="n" rel="next">Hex Floats</a>, Previous: <a href="Half_002dPrecision.html#Half_002dPrecision" accesskey="p" rel="previous">Half-Precision</a>, Up: <a href="C-Extensions.html#C-Extensions" accesskey="u" rel="up">C Extensions</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Indices.html#Indices" title="Index" rel="index">Index</a>]</p> +</div> + + + +</body> +</html> |