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diff --git a/share/doc/gcc/MIPS-Function-Attributes.html b/share/doc/gcc/MIPS-Function-Attributes.html new file mode 100644 index 0000000..848c4ec --- /dev/null +++ b/share/doc/gcc/MIPS-Function-Attributes.html @@ -0,0 +1,232 @@ +<!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): MIPS Function Attributes</title> + +<meta name="description" content="Using the GNU Compiler Collection (GCC): MIPS Function Attributes"> +<meta name="keywords" content="Using the GNU Compiler Collection (GCC): MIPS Function Attributes"> +<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="Function-Attributes.html#Function-Attributes" rel="up" title="Function Attributes"> +<link href="MSP430-Function-Attributes.html#MSP430-Function-Attributes" rel="next" title="MSP430 Function Attributes"> +<link href="Microsoft-Windows-Function-Attributes.html#Microsoft-Windows-Function-Attributes" rel="previous" title="Microsoft Windows Function Attributes"> +<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="MIPS-Function-Attributes"></a> +<div class="header"> +<p> +Next: <a href="MSP430-Function-Attributes.html#MSP430-Function-Attributes" accesskey="n" rel="next">MSP430 Function Attributes</a>, Previous: <a href="Microsoft-Windows-Function-Attributes.html#Microsoft-Windows-Function-Attributes" accesskey="p" rel="previous">Microsoft Windows Function Attributes</a>, Up: <a href="Function-Attributes.html#Function-Attributes" accesskey="u" rel="up">Function Attributes</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="MIPS-Function-Attributes-1"></a> +<h4 class="subsection">6.33.19 MIPS Function Attributes</h4> + +<p>These function attributes are supported by the MIPS back end: +</p> +<dl compact="compact"> +<dd><a name="index-interrupt-function-attribute_002c-MIPS"></a> +</dd> +<dt><code>interrupt</code></dt> +<dd><p>Use this attribute to indicate that the specified function is an interrupt +handler. The compiler generates function entry and exit sequences suitable +for use in an interrupt handler when this attribute is present. +An optional argument is supported for the interrupt attribute which allows +the interrupt mode to be described. By default GCC assumes the external +interrupt controller (EIC) mode is in use, this can be explicitly set using +<code>eic</code>. When interrupts are non-masked then the requested Interrupt +Priority Level (IPL) is copied to the current IPL which has the effect of only +enabling higher priority interrupts. To use vectored interrupt mode use +the argument <code>vector=[sw0|sw1|hw0|hw1|hw2|hw3|hw4|hw5]</code>, this will change +the behavior of the non-masked interrupt support and GCC will arrange to mask +all interrupts from sw0 up to and including the specified interrupt vector. +</p> +<p>You can use the following attributes to modify the behavior +of an interrupt handler: +</p><dl compact="compact"> +<dd><a name="index-use_005fshadow_005fregister_005fset-function-attribute_002c-MIPS"></a> +</dd> +<dt><code>use_shadow_register_set</code></dt> +<dd><p>Assume that the handler uses a shadow register set, instead of +the main general-purpose registers. An optional argument <code>intstack</code> is +supported to indicate that the shadow register set contains a valid stack +pointer. +</p> +<a name="index-keep_005finterrupts_005fmasked-function-attribute_002c-MIPS"></a> +</dd> +<dt><code>keep_interrupts_masked</code></dt> +<dd><p>Keep interrupts masked for the whole function. Without this attribute, +GCC tries to reenable interrupts for as much of the function as it can. +</p> +<a name="index-use_005fdebug_005fexception_005freturn-function-attribute_002c-MIPS"></a> +</dd> +<dt><code>use_debug_exception_return</code></dt> +<dd><p>Return using the <code>deret</code> instruction. Interrupt handlers that don’t +have this attribute return using <code>eret</code> instead. +</p></dd> +</dl> + +<p>You can use any combination of these attributes, as shown below: +</p><div class="smallexample"> +<pre class="smallexample">void __attribute__ ((interrupt)) v0 (); +void __attribute__ ((interrupt, use_shadow_register_set)) v1 (); +void __attribute__ ((interrupt, keep_interrupts_masked)) v2 (); +void __attribute__ ((interrupt, use_debug_exception_return)) v3 (); +void __attribute__ ((interrupt, use_shadow_register_set, + keep_interrupts_masked)) v4 (); +void __attribute__ ((interrupt, use_shadow_register_set, + use_debug_exception_return)) v5 (); +void __attribute__ ((interrupt, keep_interrupts_masked, + use_debug_exception_return)) v6 (); +void __attribute__ ((interrupt, use_shadow_register_set, + keep_interrupts_masked, + use_debug_exception_return)) v7 (); +void __attribute__ ((interrupt("eic"))) v8 (); +void __attribute__ ((interrupt("vector=hw3"))) v9 (); +</pre></div> + +<a name="index-indirect-calls_002c-MIPS"></a> +<a name="index-long_005fcall-function-attribute_002c-MIPS"></a> +<a name="index-short_005fcall-function-attribute_002c-MIPS"></a> +<a name="index-near-function-attribute_002c-MIPS"></a> +<a name="index-far-function-attribute_002c-MIPS"></a> +</dd> +<dt><code>long_call</code></dt> +<dt><code>short_call</code></dt> +<dt><code>near</code></dt> +<dt><code>far</code></dt> +<dd><p>These attributes specify how a particular function is called on MIPS. +The attributes override the <samp>-mlong-calls</samp> (see <a href="MIPS-Options.html#MIPS-Options">MIPS Options</a>) +command-line switch. The <code>long_call</code> and <code>far</code> attributes are +synonyms, and cause the compiler to always call +the function by first loading its address into a register, and then using +the contents of that register. The <code>short_call</code> and <code>near</code> +attributes are synonyms, and have the opposite +effect; they specify that non-PIC calls should be made using the more +efficient <code>jal</code> instruction. +</p> +<a name="index-mips16-function-attribute_002c-MIPS"></a> +<a name="index-nomips16-function-attribute_002c-MIPS"></a> +</dd> +<dt><code>mips16</code></dt> +<dt><code>nomips16</code></dt> +<dd> +<p>On MIPS targets, you can use the <code>mips16</code> and <code>nomips16</code> +function attributes to locally select or turn off MIPS16 code generation. +A function with the <code>mips16</code> attribute is emitted as MIPS16 code, +while MIPS16 code generation is disabled for functions with the +<code>nomips16</code> attribute. These attributes override the +<samp>-mips16</samp> and <samp>-mno-mips16</samp> options on the command line +(see <a href="MIPS-Options.html#MIPS-Options">MIPS Options</a>). +</p> +<p>When compiling files containing mixed MIPS16 and non-MIPS16 code, the +preprocessor symbol <code>__mips16</code> reflects the setting on the command line, +not that within individual functions. Mixed MIPS16 and non-MIPS16 code +may interact badly with some GCC extensions such as <code>__builtin_apply</code> +(see <a href="Constructing-Calls.html#Constructing-Calls">Constructing Calls</a>). +</p> +<a name="index-micromips-function-attribute"></a> +<a name="index-nomicromips-function-attribute"></a> +</dd> +<dt><code>micromips, MIPS</code></dt> +<dt><code>nomicromips, MIPS</code></dt> +<dd> +<p>On MIPS targets, you can use the <code>micromips</code> and <code>nomicromips</code> +function attributes to locally select or turn off microMIPS code generation. +A function with the <code>micromips</code> attribute is emitted as microMIPS code, +while microMIPS code generation is disabled for functions with the +<code>nomicromips</code> attribute. These attributes override the +<samp>-mmicromips</samp> and <samp>-mno-micromips</samp> options on the command line +(see <a href="MIPS-Options.html#MIPS-Options">MIPS Options</a>). +</p> +<p>When compiling files containing mixed microMIPS and non-microMIPS code, the +preprocessor symbol <code>__mips_micromips</code> reflects the setting on the +command line, +not that within individual functions. Mixed microMIPS and non-microMIPS code +may interact badly with some GCC extensions such as <code>__builtin_apply</code> +(see <a href="Constructing-Calls.html#Constructing-Calls">Constructing Calls</a>). +</p> +<a name="index-nocompression-function-attribute_002c-MIPS"></a> +</dd> +<dt><code>nocompression</code></dt> +<dd><p>On MIPS targets, you can use the <code>nocompression</code> function attribute +to locally turn off MIPS16 and microMIPS code generation. This attribute +overrides the <samp>-mips16</samp> and <samp>-mmicromips</samp> options on the +command line (see <a href="MIPS-Options.html#MIPS-Options">MIPS Options</a>). +</p> +<a name="index-use_005fhazard_005fbarrier_005freturn-function-attribute_002c-MIPS"></a> +</dd> +<dt><code>use_hazard_barrier_return</code></dt> +<dd><p>This function attribute instructs the compiler to generate a hazard barrier +return that clears all execution and instruction hazards while returning, +instead of generating a normal return instruction. +</p></dd> +</dl> + +<hr> +<div class="header"> +<p> +Next: <a href="MSP430-Function-Attributes.html#MSP430-Function-Attributes" accesskey="n" rel="next">MSP430 Function Attributes</a>, Previous: <a href="Microsoft-Windows-Function-Attributes.html#Microsoft-Windows-Function-Attributes" accesskey="p" rel="previous">Microsoft Windows Function Attributes</a>, Up: <a href="Function-Attributes.html#Function-Attributes" accesskey="u" rel="up">Function Attributes</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> |