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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/Hex-Floats.html | |
https://developer.arm.com/downloads/-/arm-gnu-toolchain-downloads
Change-Id: I7303388733328cd98ab9aa3c30236db67f2e9e9c
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diff --git a/share/doc/gcc/Hex-Floats.html b/share/doc/gcc/Hex-Floats.html new file mode 100644 index 0000000..eb22a5e --- /dev/null +++ b/share/doc/gcc/Hex-Floats.html @@ -0,0 +1,105 @@ +<!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): Hex Floats</title> + +<meta name="description" content="Using the GNU Compiler Collection (GCC): Hex Floats"> +<meta name="keywords" content="Using the GNU Compiler Collection (GCC): Hex Floats"> +<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="Fixed_002dPoint.html#Fixed_002dPoint" rel="next" title="Fixed-Point"> +<link href="Decimal-Float.html#Decimal-Float" rel="previous" title="Decimal Float"> +<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="Hex-Floats"></a> +<div class="header"> +<p> +Next: <a href="Fixed_002dPoint.html#Fixed_002dPoint" accesskey="n" rel="next">Fixed-Point</a>, Previous: <a href="Decimal-Float.html#Decimal-Float" accesskey="p" rel="previous">Decimal Float</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="Hex-Floats-1"></a> +<h3 class="section">6.15 Hex Floats</h3> +<a name="index-hex-floats"></a> + +<p>ISO C99 and ISO C++17 support floating-point numbers written not only in +the usual decimal notation, such as <code>1.55e1</code>, but also numbers such as +<code>0x1.fp3</code> written in hexadecimal format. As a GNU extension, GCC +supports this in C90 mode (except in some cases when strictly +conforming) and in C++98, C++11 and C++14 modes. In that format the +‘<samp>0x</samp>’ hex introducer and the ‘<samp>p</samp>’ or ‘<samp>P</samp>’ exponent field are +mandatory. The exponent is a decimal number that indicates the power of +2 by which the significant part is multiplied. Thus ‘<samp>0x1.f</samp>’ is +1 15/16, +‘<samp>p3</samp>’ multiplies it by 8, and the value of <code>0x1.fp3</code> +is the same as <code>1.55e1</code>. +</p> +<p>Unlike for floating-point numbers in the decimal notation the exponent +is always required in the hexadecimal notation. Otherwise the compiler +would not be able to resolve the ambiguity of, e.g., <code>0x1.f</code>. This +could mean <code>1.0f</code> or <code>1.9375</code> since ‘<samp>f</samp>’ is also the +extension for floating-point constants of type <code>float</code>. +</p> + + + +</body> +</html> |