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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/stabs/Arrays.html | |
https://developer.arm.com/downloads/-/arm-gnu-toolchain-downloads
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diff --git a/share/doc/stabs/Arrays.html b/share/doc/stabs/Arrays.html new file mode 100644 index 0000000..58ab68a --- /dev/null +++ b/share/doc/stabs/Arrays.html @@ -0,0 +1,159 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- Copyright (C) 1992-2023 Free Software Foundation, Inc. +Contributed by Cygnus Support. Written by Julia Menapace, Jim Kingdon, +and David MacKenzie. + +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 no +Invariant Sections, with no Front-Cover Texts, and with no Back-Cover +Texts. A copy of the license is included in the section entitled "GNU +Free Documentation License". --> +<!-- Created by GNU Texinfo 5.1, http://www.gnu.org/software/texinfo/ --> +<head> +<title>STABS: Arrays</title> + +<meta name="description" content="STABS: Arrays"> +<meta name="keywords" content="STABS: Arrays"> +<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="Symbol-Types-Index.html#Symbol-Types-Index" rel="index" title="Symbol Types Index"> +<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> +<link href="Types.html#Types" rel="up" title="Types"> +<link href="Strings.html#Strings" rel="next" title="Strings"> +<link href="Subranges.html#Subranges" rel="previous" title="Subranges"> +<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="Arrays"></a> +<div class="header"> +<p> +Next: <a href="Strings.html#Strings" accesskey="n" rel="next">Strings</a>, Previous: <a href="Subranges.html#Subranges" accesskey="p" rel="previous">Subranges</a>, Up: <a href="Types.html#Types" accesskey="u" rel="up">Types</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Symbol-Types-Index.html#Symbol-Types-Index" title="Index" rel="index">Index</a>]</p> +</div> +<hr> +<a name="Array-Types"></a> +<h3 class="section">5.5 Array Types</h3> + +<p>Arrays use the ‘<samp>a</samp>’ type descriptor. Following the type descriptor +is the type of the index and the type of the array elements. If the +index type is a range type, it ends in a semicolon; otherwise +(for example, if it is a type reference), there does not +appear to be any way to tell where the types are separated. In an +effort to clean up this mess, IBM documents the two types as being +separated by a semicolon, and a range type as not ending in a semicolon +(but this is not right for range types which are not array indexes, +see <a href="Subranges.html#Subranges">Subranges</a>). I think probably the best solution is to specify +that a semicolon ends a range type, and that the index type and element +type of an array are separated by a semicolon, but that if the index +type is a range type, the extra semicolon can be omitted. GDB (at least +through version 4.9) doesn’t support any kind of index type other than a +range anyway; I’m not sure about dbx. +</p> +<p>It is well established, and widely used, that the type of the index, +unlike most types found in the stabs, is merely a type definition, not +type information (see <a href="String-Field.html#String-Field">String Field</a>) (that is, it need not start with +‘<samp><var>type-number</var>=</samp>’ if it is defining a new type). According to a +comment in GDB, this is also true of the type of the array elements; it +gives ‘<samp>ar1;1;10;ar1;1;10;4</samp>’ as a legitimate way to express a two +dimensional array. According to AIX documentation, the element type +must be type information. GDB accepts either. +</p> +<p>The type of the index is often a range type, expressed as the type +descriptor ‘<samp>r</samp>’ and some parameters. It defines the size of the +array. In the example below, the range ‘<samp>r1;0;2;</samp>’ defines an index +type which is a subrange of type 1 (integer), with a lower bound of 0 +and an upper bound of 2. This defines the valid range of subscripts of +a three-element C array. +</p> +<p>For example, the definition: +</p> +<div class="example"> +<pre class="example">char char_vec[3] = {'a','b','c'}; +</pre></div> + +<p>produces the output: +</p> +<div class="example"> +<pre class="example">.stabs "char_vec:G19=ar1;0;2;2",32,0,0,0 + .global _char_vec + .align 4 +_char_vec: + .byte 97 + .byte 98 + .byte 99 +</pre></div> + +<p>If an array is <em>packed</em>, the elements are spaced more +closely than normal, saving memory at the expense of speed. For +example, an array of 3-byte objects might, if unpacked, have each +element aligned on a 4-byte boundary, but if packed, have no padding. +One way to specify that something is packed is with type attributes +(see <a href="String-Field.html#String-Field">String Field</a>). In the case of arrays, another is to use the +‘<samp>P</samp>’ type descriptor instead of ‘<samp>a</samp>’. Other than specifying a +packed array, ‘<samp>P</samp>’ is identical to ‘<samp>a</samp>’. +</p> +<p>An open array is represented by the ‘<samp>A</samp>’ type descriptor followed by +type information specifying the type of the array elements. +</p> +<p>An N-dimensional dynamic array is represented by +</p> +<div class="example"> +<pre class="example">D <var>dimensions</var> ; <var>type-information</var> +</pre></div> + +<p><var>dimensions</var> is the number of dimensions; <var>type-information</var> +specifies the type of the array elements. +</p> +<p>A subarray of an N-dimensional array is represented by +</p> +<div class="example"> +<pre class="example">E <var>dimensions</var> ; <var>type-information</var> +</pre></div> + +<p><var>dimensions</var> is the number of dimensions; <var>type-information</var> +specifies the type of the array elements. +</p> +<hr> +<div class="header"> +<p> +Next: <a href="Strings.html#Strings" accesskey="n" rel="next">Strings</a>, Previous: <a href="Subranges.html#Subranges" accesskey="p" rel="previous">Subranges</a>, Up: <a href="Types.html#Types" accesskey="u" rel="up">Types</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Symbol-Types-Index.html#Symbol-Types-Index" title="Index" rel="index">Index</a>]</p> +</div> + + + +</body> +</html> |