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diff --git a/share/doc/gccint/Storage-References.html b/share/doc/gccint/Storage-References.html new file mode 100644 index 0000000..25c3dc5 --- /dev/null +++ b/share/doc/gccint/Storage-References.html @@ -0,0 +1,179 @@ +<!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: Storage References</title> + +<meta name="description" content="GNU Compiler Collection (GCC) Internals: Storage References"> +<meta name="keywords" content="GNU Compiler Collection (GCC) Internals: Storage References"> +<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="Expression-trees.html#Expression-trees" rel="up" title="Expression trees"> +<link href="Unary-and-Binary-Expressions.html#Unary-and-Binary-Expressions" rel="next" title="Unary and Binary Expressions"> +<link href="Constant-expressions.html#Constant-expressions" rel="previous" title="Constant expressions"> +<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="Storage-References"></a> +<div class="header"> +<p> +Next: <a href="Unary-and-Binary-Expressions.html#Unary-and-Binary-Expressions" accesskey="n" rel="next">Unary and Binary Expressions</a>, Previous: <a href="Constant-expressions.html#Constant-expressions" accesskey="p" rel="previous">Constant expressions</a>, Up: <a href="Expression-trees.html#Expression-trees" accesskey="u" rel="up">Expression trees</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="References-to-storage"></a> +<h4 class="subsection">11.6.2 References to storage</h4> +<a name="index-ADDR_005fEXPR"></a> +<a name="index-INDIRECT_005fREF"></a> +<a name="index-MEM_005fREF"></a> +<a name="index-ARRAY_005fREF"></a> +<a name="index-ARRAY_005fRANGE_005fREF"></a> +<a name="index-TARGET_005fMEM_005fREF"></a> +<a name="index-COMPONENT_005fREF"></a> + +<dl compact="compact"> +<dt><code>ARRAY_REF</code></dt> +<dd><p>These nodes represent array accesses. The first operand is the array; +the second is the index. To calculate the address of the memory +accessed, you must scale the index by the size of the type of the array +elements. The type of these expressions must be the type of a component of +the array. The third and fourth operands are used after gimplification +to represent the lower bound and component size but should not be used +directly; call <code>array_ref_low_bound</code> and <code>array_ref_element_size</code> +instead. +</p> +</dd> +<dt><code>ARRAY_RANGE_REF</code></dt> +<dd><p>These nodes represent access to a range (or “slice”) of an array. The +operands are the same as that for <code>ARRAY_REF</code> and have the same +meanings. The type of these expressions must be an array whose component +type is the same as that of the first operand. The range of that array +type determines the amount of data these expressions access. +</p> +</dd> +<dt><code>COMPONENT_REF</code></dt> +<dd><p>These nodes represent non-static data member accesses. The first +operand is the object (rather than a pointer to it); the second operand +is the <code>FIELD_DECL</code> for the data member. The third operand represents +the byte offset of the field, but should not be used directly; call +<code>component_ref_field_offset</code> instead. +</p> +</dd> +<dt><code>ADDR_EXPR</code></dt> +<dd><p>These nodes are used to represent the address of an object. (These +expressions will always have pointer or reference type.) The operand may +be another expression, or it may be a declaration. +</p> +<p>As an extension, GCC allows users to take the address of a label. In +this case, the operand of the <code>ADDR_EXPR</code> will be a +<code>LABEL_DECL</code>. The type of such an expression is <code>void*</code>. +</p> +<p>If the object addressed is not an lvalue, a temporary is created, and +the address of the temporary is used. +</p> +</dd> +<dt><code>INDIRECT_REF</code></dt> +<dd><p>These nodes are used to represent the object pointed to by a pointer. +The operand is the pointer being dereferenced; it will always have +pointer or reference type. +</p> +</dd> +<dt><code>MEM_REF</code></dt> +<dd><p>These nodes are used to represent the object pointed to by a pointer +offset by a constant. +The first operand is the pointer being dereferenced; it will always have +pointer or reference type. The second operand is a pointer constant +serving as constant offset applied to the pointer being dereferenced +with its type specifying the type to be used for type-based alias analysis. +The type of the node specifies the alignment of the access. +</p> +</dd> +<dt><code>TARGET_MEM_REF</code></dt> +<dd><p>These nodes represent memory accesses whose address directly map to +an addressing mode of the target architecture. The first argument +is <code>TMR_BASE</code> and is a pointer to the object being accessed. +The second argument is <code>TMR_OFFSET</code> which is a pointer constant +with dual purpose serving both as constant offset and holder of +the type used for type-based alias analysis. The first two operands +have exactly the same semantics as <code>MEM_REF</code>. The third +and fourth operand are <code>TMR_INDEX</code> and <code>TMR_STEP</code> where +the former is an integer and the latter an integer constant. The +fifth and last operand is <code>TMR_INDEX2</code> which is an alternate +non-constant offset. Any of the third to last operands may be +<code>NULL</code> if the corresponding component does not appear in +the address, but <code>TMR_INDEX</code> and <code>TMR_STEP</code> shall be +always supplied in pair. The Address of the <code>TARGET_MEM_REF</code> +is determined in the following way. +</p> +<div class="smallexample"> +<pre class="smallexample">TMR_BASE + TMR_OFFSET + TMR_INDEX * TMR_STEP + TMR_INDEX2 +</pre></div> + +<p>The type of the node specifies the alignment of the access. +</p> +</dd> +</dl> + +<hr> +<div class="header"> +<p> +Next: <a href="Unary-and-Binary-Expressions.html#Unary-and-Binary-Expressions" accesskey="n" rel="next">Unary and Binary Expressions</a>, Previous: <a href="Constant-expressions.html#Constant-expressions" accesskey="p" rel="previous">Constant expressions</a>, Up: <a href="Expression-trees.html#Expression-trees" accesskey="u" rel="up">Expression trees</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> |