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diff --git a/share/doc/gccint/Integer-library-routines.html b/share/doc/gccint/Integer-library-routines.html new file mode 100644 index 0000000..df5736b --- /dev/null +++ b/share/doc/gccint/Integer-library-routines.html @@ -0,0 +1,286 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- 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>GNU Compiler Collection (GCC) Internals: Integer library routines</title> + +<meta name="description" content="GNU Compiler Collection (GCC) Internals: Integer library routines"> +<meta name="keywords" content="GNU Compiler Collection (GCC) Internals: Integer library routines"> +<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="Libgcc.html#Libgcc" rel="up" title="Libgcc"> +<link href="Soft-float-library-routines.html#Soft-float-library-routines" rel="next" title="Soft float library routines"> +<link href="Libgcc.html#Libgcc" rel="previous" title="Libgcc"> +<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="Integer-library-routines"></a> +<div class="header"> +<p> +Next: <a href="Soft-float-library-routines.html#Soft-float-library-routines" accesskey="n" rel="next">Soft float library routines</a>, Up: <a href="Libgcc.html#Libgcc" accesskey="u" rel="up">Libgcc</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="Routines-for-integer-arithmetic"></a> +<h3 class="section">4.1 Routines for integer arithmetic</h3> + +<p>The integer arithmetic routines are used on platforms that don’t provide +hardware support for arithmetic operations on some modes. +</p> +<a name="Arithmetic-functions"></a> +<h4 class="subsection">4.1.1 Arithmetic functions</h4> + +<dl> +<dt><a name="index-_005f_005fashlsi3"></a>Runtime Function: <em>int</em> <strong>__ashlsi3</strong> <em>(int <var>a</var>, int <var>b</var>)</em></dt> +<dt><a name="index-_005f_005fashldi3"></a>Runtime Function: <em>long</em> <strong>__ashldi3</strong> <em>(long <var>a</var>, int <var>b</var>)</em></dt> +<dt><a name="index-_005f_005fashlti3"></a>Runtime Function: <em>long long</em> <strong>__ashlti3</strong> <em>(long long <var>a</var>, int <var>b</var>)</em></dt> +<dd><p>These functions return the result of shifting <var>a</var> left by <var>b</var> bits. +</p></dd></dl> + +<dl> +<dt><a name="index-_005f_005fashrsi3"></a>Runtime Function: <em>int</em> <strong>__ashrsi3</strong> <em>(int <var>a</var>, int <var>b</var>)</em></dt> +<dt><a name="index-_005f_005fashrdi3"></a>Runtime Function: <em>long</em> <strong>__ashrdi3</strong> <em>(long <var>a</var>, int <var>b</var>)</em></dt> +<dt><a name="index-_005f_005fashrti3"></a>Runtime Function: <em>long long</em> <strong>__ashrti3</strong> <em>(long long <var>a</var>, int <var>b</var>)</em></dt> +<dd><p>These functions return the result of arithmetically shifting <var>a</var> right +by <var>b</var> bits. +</p></dd></dl> + +<dl> +<dt><a name="index-_005f_005fdivsi3"></a>Runtime Function: <em>int</em> <strong>__divsi3</strong> <em>(int <var>a</var>, int <var>b</var>)</em></dt> +<dt><a name="index-_005f_005fdivdi3"></a>Runtime Function: <em>long</em> <strong>__divdi3</strong> <em>(long <var>a</var>, long <var>b</var>)</em></dt> +<dt><a name="index-_005f_005fdivti3"></a>Runtime Function: <em>long long</em> <strong>__divti3</strong> <em>(long long <var>a</var>, long long <var>b</var>)</em></dt> +<dd><p>These functions return the quotient of the signed division of <var>a</var> and +<var>b</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-_005f_005flshrsi3"></a>Runtime Function: <em>int</em> <strong>__lshrsi3</strong> <em>(int <var>a</var>, int <var>b</var>)</em></dt> +<dt><a name="index-_005f_005flshrdi3"></a>Runtime Function: <em>long</em> <strong>__lshrdi3</strong> <em>(long <var>a</var>, int <var>b</var>)</em></dt> +<dt><a name="index-_005f_005flshrti3"></a>Runtime Function: <em>long long</em> <strong>__lshrti3</strong> <em>(long long <var>a</var>, int <var>b</var>)</em></dt> +<dd><p>These functions return the result of logically shifting <var>a</var> right by +<var>b</var> bits. +</p></dd></dl> + +<dl> +<dt><a name="index-_005f_005fmodsi3"></a>Runtime Function: <em>int</em> <strong>__modsi3</strong> <em>(int <var>a</var>, int <var>b</var>)</em></dt> +<dt><a name="index-_005f_005fmoddi3"></a>Runtime Function: <em>long</em> <strong>__moddi3</strong> <em>(long <var>a</var>, long <var>b</var>)</em></dt> +<dt><a name="index-_005f_005fmodti3"></a>Runtime Function: <em>long long</em> <strong>__modti3</strong> <em>(long long <var>a</var>, long long <var>b</var>)</em></dt> +<dd><p>These functions return the remainder of the signed division of <var>a</var> +and <var>b</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-_005f_005fmulsi3"></a>Runtime Function: <em>int</em> <strong>__mulsi3</strong> <em>(int <var>a</var>, int <var>b</var>)</em></dt> +<dt><a name="index-_005f_005fmuldi3"></a>Runtime Function: <em>long</em> <strong>__muldi3</strong> <em>(long <var>a</var>, long <var>b</var>)</em></dt> +<dt><a name="index-_005f_005fmulti3"></a>Runtime Function: <em>long long</em> <strong>__multi3</strong> <em>(long long <var>a</var>, long long <var>b</var>)</em></dt> +<dd><p>These functions return the product of <var>a</var> and <var>b</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-_005f_005fnegdi2"></a>Runtime Function: <em>long</em> <strong>__negdi2</strong> <em>(long <var>a</var>)</em></dt> +<dt><a name="index-_005f_005fnegti2"></a>Runtime Function: <em>long long</em> <strong>__negti2</strong> <em>(long long <var>a</var>)</em></dt> +<dd><p>These functions return the negation of <var>a</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-_005f_005fudivsi3"></a>Runtime Function: <em>unsigned int</em> <strong>__udivsi3</strong> <em>(unsigned int <var>a</var>, unsigned int <var>b</var>)</em></dt> +<dt><a name="index-_005f_005fudivdi3"></a>Runtime Function: <em>unsigned long</em> <strong>__udivdi3</strong> <em>(unsigned long <var>a</var>, unsigned long <var>b</var>)</em></dt> +<dt><a name="index-_005f_005fudivti3"></a>Runtime Function: <em>unsigned long long</em> <strong>__udivti3</strong> <em>(unsigned long long <var>a</var>, unsigned long long <var>b</var>)</em></dt> +<dd><p>These functions return the quotient of the unsigned division of <var>a</var> +and <var>b</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-_005f_005fudivmoddi4"></a>Runtime Function: <em>unsigned long</em> <strong>__udivmoddi4</strong> <em>(unsigned long <var>a</var>, unsigned long <var>b</var>, unsigned long *<var>c</var>)</em></dt> +<dt><a name="index-_005f_005fudivmodti4"></a>Runtime Function: <em>unsigned long long</em> <strong>__udivmodti4</strong> <em>(unsigned long long <var>a</var>, unsigned long long <var>b</var>, unsigned long long *<var>c</var>)</em></dt> +<dd><p>These functions calculate both the quotient and remainder of the unsigned +division of <var>a</var> and <var>b</var>. The return value is the quotient, and +the remainder is placed in variable pointed to by <var>c</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-_005f_005fumodsi3"></a>Runtime Function: <em>unsigned int</em> <strong>__umodsi3</strong> <em>(unsigned int <var>a</var>, unsigned int <var>b</var>)</em></dt> +<dt><a name="index-_005f_005fumoddi3"></a>Runtime Function: <em>unsigned long</em> <strong>__umoddi3</strong> <em>(unsigned long <var>a</var>, unsigned long <var>b</var>)</em></dt> +<dt><a name="index-_005f_005fumodti3"></a>Runtime Function: <em>unsigned long long</em> <strong>__umodti3</strong> <em>(unsigned long long <var>a</var>, unsigned long long <var>b</var>)</em></dt> +<dd><p>These functions return the remainder of the unsigned division of <var>a</var> +and <var>b</var>. +</p></dd></dl> + +<a name="Comparison-functions"></a> +<h4 class="subsection">4.1.2 Comparison functions</h4> + +<p>The following functions implement integral comparisons. These functions +implement a low-level compare, upon which the higher level comparison +operators (such as less than and greater than or equal to) can be +constructed. The returned values lie in the range zero to two, to allow +the high-level operators to be implemented by testing the returned +result using either signed or unsigned comparison. +</p> +<dl> +<dt><a name="index-_005f_005fcmpdi2"></a>Runtime Function: <em>int</em> <strong>__cmpdi2</strong> <em>(long <var>a</var>, long <var>b</var>)</em></dt> +<dt><a name="index-_005f_005fcmpti2"></a>Runtime Function: <em>int</em> <strong>__cmpti2</strong> <em>(long long <var>a</var>, long long <var>b</var>)</em></dt> +<dd><p>These functions perform a signed comparison of <var>a</var> and <var>b</var>. If +<var>a</var> is less than <var>b</var>, they return 0; if <var>a</var> is greater than +<var>b</var>, they return 2; and if <var>a</var> and <var>b</var> are equal they return 1. +</p></dd></dl> + +<dl> +<dt><a name="index-_005f_005fucmpdi2"></a>Runtime Function: <em>int</em> <strong>__ucmpdi2</strong> <em>(unsigned long <var>a</var>, unsigned long <var>b</var>)</em></dt> +<dt><a name="index-_005f_005fucmpti2"></a>Runtime Function: <em>int</em> <strong>__ucmpti2</strong> <em>(unsigned long long <var>a</var>, unsigned long long <var>b</var>)</em></dt> +<dd><p>These functions perform an unsigned comparison of <var>a</var> and <var>b</var>. +If <var>a</var> is less than <var>b</var>, they return 0; if <var>a</var> is greater than +<var>b</var>, they return 2; and if <var>a</var> and <var>b</var> are equal they return 1. +</p></dd></dl> + +<a name="Trapping-arithmetic-functions"></a> +<h4 class="subsection">4.1.3 Trapping arithmetic functions</h4> + +<p>The following functions implement trapping arithmetic. These functions +call the libc function <code>abort</code> upon signed arithmetic overflow. +</p> +<dl> +<dt><a name="index-_005f_005fabsvsi2"></a>Runtime Function: <em>int</em> <strong>__absvsi2</strong> <em>(int <var>a</var>)</em></dt> +<dt><a name="index-_005f_005fabsvdi2"></a>Runtime Function: <em>long</em> <strong>__absvdi2</strong> <em>(long <var>a</var>)</em></dt> +<dd><p>These functions return the absolute value of <var>a</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-_005f_005faddvsi3"></a>Runtime Function: <em>int</em> <strong>__addvsi3</strong> <em>(int <var>a</var>, int <var>b</var>)</em></dt> +<dt><a name="index-_005f_005faddvdi3"></a>Runtime Function: <em>long</em> <strong>__addvdi3</strong> <em>(long <var>a</var>, long <var>b</var>)</em></dt> +<dd><p>These functions return the sum of <var>a</var> and <var>b</var>; that is +<code><var>a</var> + <var>b</var></code>. +</p></dd></dl> + +<dl> +<dt><a name="index-_005f_005fmulvsi3"></a>Runtime Function: <em>int</em> <strong>__mulvsi3</strong> <em>(int <var>a</var>, int <var>b</var>)</em></dt> +<dt><a name="index-_005f_005fmulvdi3"></a>Runtime Function: <em>long</em> <strong>__mulvdi3</strong> <em>(long <var>a</var>, long <var>b</var>)</em></dt> +<dd><p>The functions return the product of <var>a</var> and <var>b</var>; that is +<code><var>a</var> * <var>b</var></code>. +</p></dd></dl> + +<dl> +<dt><a name="index-_005f_005fnegvsi2"></a>Runtime Function: <em>int</em> <strong>__negvsi2</strong> <em>(int <var>a</var>)</em></dt> +<dt><a name="index-_005f_005fnegvdi2"></a>Runtime Function: <em>long</em> <strong>__negvdi2</strong> <em>(long <var>a</var>)</em></dt> +<dd><p>These functions return the negation of <var>a</var>; that is <code>-<var>a</var></code>. +</p></dd></dl> + +<dl> +<dt><a name="index-_005f_005fsubvsi3"></a>Runtime Function: <em>int</em> <strong>__subvsi3</strong> <em>(int <var>a</var>, int <var>b</var>)</em></dt> +<dt><a name="index-_005f_005fsubvdi3"></a>Runtime Function: <em>long</em> <strong>__subvdi3</strong> <em>(long <var>a</var>, long <var>b</var>)</em></dt> +<dd><p>These functions return the difference between <var>b</var> and <var>a</var>; +that is <code><var>a</var> - <var>b</var></code>. +</p></dd></dl> + +<a name="Bit-operations"></a> +<h4 class="subsection">4.1.4 Bit operations</h4> + +<dl> +<dt><a name="index-_005f_005fclzsi2"></a>Runtime Function: <em>int</em> <strong>__clzsi2</strong> <em>(unsigned int <var>a</var>)</em></dt> +<dt><a name="index-_005f_005fclzdi2"></a>Runtime Function: <em>int</em> <strong>__clzdi2</strong> <em>(unsigned long <var>a</var>)</em></dt> +<dt><a name="index-_005f_005fclzti2"></a>Runtime Function: <em>int</em> <strong>__clzti2</strong> <em>(unsigned long long <var>a</var>)</em></dt> +<dd><p>These functions return the number of leading 0-bits in <var>a</var>, starting +at the most significant bit position. If <var>a</var> is zero, the result is +undefined. +</p></dd></dl> + +<dl> +<dt><a name="index-_005f_005fctzsi2"></a>Runtime Function: <em>int</em> <strong>__ctzsi2</strong> <em>(unsigned int <var>a</var>)</em></dt> +<dt><a name="index-_005f_005fctzdi2"></a>Runtime Function: <em>int</em> <strong>__ctzdi2</strong> <em>(unsigned long <var>a</var>)</em></dt> +<dt><a name="index-_005f_005fctzti2"></a>Runtime Function: <em>int</em> <strong>__ctzti2</strong> <em>(unsigned long long <var>a</var>)</em></dt> +<dd><p>These functions return the number of trailing 0-bits in <var>a</var>, starting +at the least significant bit position. If <var>a</var> is zero, the result is +undefined. +</p></dd></dl> + +<dl> +<dt><a name="index-_005f_005fffsdi2"></a>Runtime Function: <em>int</em> <strong>__ffsdi2</strong> <em>(unsigned long <var>a</var>)</em></dt> +<dt><a name="index-_005f_005fffsti2"></a>Runtime Function: <em>int</em> <strong>__ffsti2</strong> <em>(unsigned long long <var>a</var>)</em></dt> +<dd><p>These functions return the index of the least significant 1-bit in <var>a</var>, +or the value zero if <var>a</var> is zero. The least significant bit is index +one. +</p></dd></dl> + +<dl> +<dt><a name="index-_005f_005fparitysi2"></a>Runtime Function: <em>int</em> <strong>__paritysi2</strong> <em>(unsigned int <var>a</var>)</em></dt> +<dt><a name="index-_005f_005fparitydi2"></a>Runtime Function: <em>int</em> <strong>__paritydi2</strong> <em>(unsigned long <var>a</var>)</em></dt> +<dt><a name="index-_005f_005fparityti2"></a>Runtime Function: <em>int</em> <strong>__parityti2</strong> <em>(unsigned long long <var>a</var>)</em></dt> +<dd><p>These functions return the value zero if the number of bits set in +<var>a</var> is even, and the value one otherwise. +</p></dd></dl> + +<dl> +<dt><a name="index-_005f_005fpopcountsi2"></a>Runtime Function: <em>int</em> <strong>__popcountsi2</strong> <em>(unsigned int <var>a</var>)</em></dt> +<dt><a name="index-_005f_005fpopcountdi2"></a>Runtime Function: <em>int</em> <strong>__popcountdi2</strong> <em>(unsigned long <var>a</var>)</em></dt> +<dt><a name="index-_005f_005fpopcountti2"></a>Runtime Function: <em>int</em> <strong>__popcountti2</strong> <em>(unsigned long long <var>a</var>)</em></dt> +<dd><p>These functions return the number of bits set in <var>a</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-_005f_005fbswapsi2"></a>Runtime Function: <em>int32_t</em> <strong>__bswapsi2</strong> <em>(int32_t <var>a</var>)</em></dt> +<dt><a name="index-_005f_005fbswapdi2"></a>Runtime Function: <em>int64_t</em> <strong>__bswapdi2</strong> <em>(int64_t <var>a</var>)</em></dt> +<dd><p>These functions return the <var>a</var> byteswapped. +</p></dd></dl> + +<hr> +<div class="header"> +<p> +Next: <a href="Soft-float-library-routines.html#Soft-float-library-routines" accesskey="n" rel="next">Soft float library routines</a>, Up: <a href="Libgcc.html#Libgcc" accesskey="u" rel="up">Libgcc</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> + + + +</body> +</html> |