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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/gccint/Library-Calls.html | |
https://developer.arm.com/downloads/-/arm-gnu-toolchain-downloads
Change-Id: I7303388733328cd98ab9aa3c30236db67f2e9e9c
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diff --git a/share/doc/gccint/Library-Calls.html b/share/doc/gccint/Library-Calls.html new file mode 100644 index 0000000..242c8d4 --- /dev/null +++ b/share/doc/gccint/Library-Calls.html @@ -0,0 +1,213 @@ +<!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: Library Calls</title> + +<meta name="description" content="GNU Compiler Collection (GCC) Internals: Library Calls"> +<meta name="keywords" content="GNU Compiler Collection (GCC) Internals: Library Calls"> +<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="Target-Macros.html#Target-Macros" rel="up" title="Target Macros"> +<link href="Addressing-Modes.html#Addressing-Modes" rel="next" title="Addressing Modes"> +<link href="Trampolines.html#Trampolines" rel="previous" title="Trampolines"> +<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="Library-Calls"></a> +<div class="header"> +<p> +Next: <a href="Addressing-Modes.html#Addressing-Modes" accesskey="n" rel="next">Addressing Modes</a>, Previous: <a href="Trampolines.html#Trampolines" accesskey="p" rel="previous">Trampolines</a>, Up: <a href="Target-Macros.html#Target-Macros" accesskey="u" rel="up">Target Macros</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="Implicit-Calls-to-Library-Routines"></a> +<h3 class="section">18.12 Implicit Calls to Library Routines</h3> +<a name="index-library-subroutine-names"></a> +<a name="index-libgcc_002ea"></a> + +<p>Here is an explanation of implicit calls to library routines. +</p> +<dl> +<dt><a name="index-DECLARE_005fLIBRARY_005fRENAMES"></a>Macro: <strong>DECLARE_LIBRARY_RENAMES</strong></dt> +<dd><p>This macro, if defined, should expand to a piece of C code that will get +expanded when compiling functions for libgcc.a. It can be used to +provide alternate names for GCC’s internal library functions if there +are ABI-mandated names that the compiler should provide. +</p></dd></dl> + +<a name="index-set_005foptab_005flibfunc"></a> +<a name="index-init_005fone_005flibfunc"></a> +<dl> +<dt><a name="index-TARGET_005fINIT_005fLIBFUNCS"></a>Target Hook: <em>void</em> <strong>TARGET_INIT_LIBFUNCS</strong> <em>(void)</em></dt> +<dd><p>This hook should declare additional library routines or rename +existing ones, using the functions <code>set_optab_libfunc</code> and +<code>init_one_libfunc</code> defined in <samp>optabs.cc</samp>. +<code>init_optabs</code> calls this macro after initializing all the normal +library routines. +</p> +<p>The default is to do nothing. Most ports don’t need to define this hook. +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fLIBFUNC_005fGNU_005fPREFIX"></a>Target Hook: <em>bool</em> <strong>TARGET_LIBFUNC_GNU_PREFIX</strong></dt> +<dd><p>If false (the default), internal library routines start with two +underscores. If set to true, these routines start with <code>__gnu_</code> +instead. E.g., <code>__muldi3</code> changes to <code>__gnu_muldi3</code>. This +currently only affects functions defined in <samp>libgcc2.c</samp>. If this +is set to true, the <samp>tm.h</samp> file must also +<code>#define LIBGCC2_GNU_PREFIX</code>. +</p></dd></dl> + +<dl> +<dt><a name="index-FLOAT_005fLIB_005fCOMPARE_005fRETURNS_005fBOOL"></a>Macro: <strong>FLOAT_LIB_COMPARE_RETURNS_BOOL</strong> <em>(<var>mode</var>, <var>comparison</var>)</em></dt> +<dd><p>This macro should return <code>true</code> if the library routine that +implements the floating point comparison operator <var>comparison</var> in +mode <var>mode</var> will return a boolean, and <var>false</var> if it will +return a tristate. +</p> +<p>GCC’s own floating point libraries return tristates from the +comparison operators, so the default returns false always. Most ports +don’t need to define this macro. +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fLIB_005fINT_005fCMP_005fBIASED"></a>Macro: <strong>TARGET_LIB_INT_CMP_BIASED</strong></dt> +<dd><p>This macro should evaluate to <code>true</code> if the integer comparison +functions (like <code>__cmpdi2</code>) return 0 to indicate that the first +operand is smaller than the second, 1 to indicate that they are equal, +and 2 to indicate that the first operand is greater than the second. +If this macro evaluates to <code>false</code> the comparison functions return +-1, 0, and 1 instead of 0, 1, and 2. If the target uses the routines +in <samp>libgcc.a</samp>, you do not need to define this macro. +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fHAS_005fNO_005fHW_005fDIVIDE"></a>Macro: <strong>TARGET_HAS_NO_HW_DIVIDE</strong></dt> +<dd><p>This macro should be defined if the target has no hardware divide +instructions. If this macro is defined, GCC will use an algorithm which +make use of simple logical and arithmetic operations for 64-bit +division. If the macro is not defined, GCC will use an algorithm which +make use of a 64-bit by 32-bit divide primitive. +</p></dd></dl> + +<a name="index-EDOM_002c-implicit-usage"></a> +<a name="index-matherr"></a> +<dl> +<dt><a name="index-TARGET_005fEDOM"></a>Macro: <strong>TARGET_EDOM</strong></dt> +<dd><p>The value of <code>EDOM</code> on the target machine, as a C integer constant +expression. If you don’t define this macro, GCC does not attempt to +deposit the value of <code>EDOM</code> into <code>errno</code> directly. Look in +<samp>/usr/include/errno.h</samp> to find the value of <code>EDOM</code> on your +system. +</p> +<p>If you do not define <code>TARGET_EDOM</code>, then compiled code reports +domain errors by calling the library function and letting it report the +error. If mathematical functions on your system use <code>matherr</code> when +there is an error, then you should leave <code>TARGET_EDOM</code> undefined so +that <code>matherr</code> is used normally. +</p></dd></dl> + +<a name="index-errno_002c-implicit-usage"></a> +<dl> +<dt><a name="index-GEN_005fERRNO_005fRTX"></a>Macro: <strong>GEN_ERRNO_RTX</strong></dt> +<dd><p>Define this macro as a C expression to create an rtl expression that +refers to the global “variable” <code>errno</code>. (On certain systems, +<code>errno</code> may not actually be a variable.) If you don’t define this +macro, a reasonable default is used. +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fLIBC_005fHAS_005fFUNCTION"></a>Target Hook: <em>bool</em> <strong>TARGET_LIBC_HAS_FUNCTION</strong> <em>(enum function_class <var>fn_class</var>, tree <var>type</var>)</em></dt> +<dd><p>This hook determines whether a function from a class of functions +<var>fn_class</var> is present in the target C library. If <var>type</var> is NULL, +the caller asks for support for all standard (float, double, long double) +types. If <var>type</var> is non-NULL, the caller asks for support for a +specific type. +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fLIBC_005fHAS_005fFAST_005fFUNCTION"></a>Target Hook: <em>bool</em> <strong>TARGET_LIBC_HAS_FAST_FUNCTION</strong> <em>(int <var>fcode</var>)</em></dt> +<dd><p>This hook determines whether a function from a class of functions +<code>(enum function_class)</code><var>fcode</var> has a fast implementation. +</p></dd></dl> + +<dl> +<dt><a name="index-NEXT_005fOBJC_005fRUNTIME"></a>Macro: <strong>NEXT_OBJC_RUNTIME</strong></dt> +<dd><p>Set this macro to 1 to use the "NeXT" Objective-C message sending conventions +by default. This calling convention involves passing the object, the selector +and the method arguments all at once to the method-lookup library function. +This is the usual setting when targeting Darwin/Mac OS X systems, which have +the NeXT runtime installed. +</p> +<p>If the macro is set to 0, the "GNU" Objective-C message sending convention +will be used by default. This convention passes just the object and the +selector to the method-lookup function, which returns a pointer to the method. +</p> +<p>In either case, it remains possible to select code-generation for the alternate +scheme, by means of compiler command line switches. +</p></dd></dl> + +<hr> +<div class="header"> +<p> +Next: <a href="Addressing-Modes.html#Addressing-Modes" accesskey="n" rel="next">Addressing Modes</a>, Previous: <a href="Trampolines.html#Trampolines" accesskey="p" rel="previous">Trampolines</a>, Up: <a href="Target-Macros.html#Target-Macros" accesskey="u" rel="up">Target Macros</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> |