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diff --git a/share/doc/gccint/Sections.html b/share/doc/gccint/Sections.html new file mode 100644 index 0000000..0202701 --- /dev/null +++ b/share/doc/gccint/Sections.html @@ -0,0 +1,487 @@ +<!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: Sections</title> + +<meta name="description" content="GNU Compiler Collection (GCC) Internals: Sections"> +<meta name="keywords" content="GNU Compiler Collection (GCC) Internals: Sections"> +<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="PIC.html#PIC" rel="next" title="PIC"> +<link href="Scheduling.html#Scheduling" rel="previous" title="Scheduling"> +<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="Sections"></a> +<div class="header"> +<p> +Next: <a href="PIC.html#PIC" accesskey="n" rel="next">PIC</a>, Previous: <a href="Scheduling.html#Scheduling" accesskey="p" rel="previous">Scheduling</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="Dividing-the-Output-into-Sections-_0028Texts_002c-Data_002c-_2026_0029"></a> +<h3 class="section">18.18 Dividing the Output into Sections (Texts, Data, …)</h3> + +<p>An object file is divided into sections containing different types of +data. In the most common case, there are three sections: the <em>text +section</em>, which holds instructions and read-only data; the <em>data +section</em>, which holds initialized writable data; and the <em>bss +section</em>, which holds uninitialized data. Some systems have other kinds +of sections. +</p> +<p><samp>varasm.cc</samp> provides several well-known sections, such as +<code>text_section</code>, <code>data_section</code> and <code>bss_section</code>. +The normal way of controlling a <code><var>foo</var>_section</code> variable +is to define the associated <code><var>FOO</var>_SECTION_ASM_OP</code> macro, +as described below. The macros are only read once, when <samp>varasm.cc</samp> +initializes itself, so their values must be run-time constants. +They may however depend on command-line flags. +</p> +<p><em>Note:</em> Some run-time files, such <samp>crtstuff.c</samp>, also make +use of the <code><var>FOO</var>_SECTION_ASM_OP</code> macros, and expect them +to be string literals. +</p> +<p>Some assemblers require a different string to be written every time a +section is selected. If your assembler falls into this category, you +should define the <code>TARGET_ASM_INIT_SECTIONS</code> hook and use +<code>get_unnamed_section</code> to set up the sections. +</p> +<p>You must always create a <code>text_section</code>, either by defining +<code>TEXT_SECTION_ASM_OP</code> or by initializing <code>text_section</code> +in <code>TARGET_ASM_INIT_SECTIONS</code>. The same is true of +<code>data_section</code> and <code>DATA_SECTION_ASM_OP</code>. If you do not +create a distinct <code>readonly_data_section</code>, the default is to +reuse <code>text_section</code>. +</p> +<p>All the other <samp>varasm.cc</samp> sections are optional, and are null +if the target does not provide them. +</p> +<dl> +<dt><a name="index-TEXT_005fSECTION_005fASM_005fOP"></a>Macro: <strong>TEXT_SECTION_ASM_OP</strong></dt> +<dd><p>A C expression whose value is a string, including spacing, containing the +assembler operation that should precede instructions and read-only data. +Normally <code>"\t.text"</code> is right. +</p></dd></dl> + +<dl> +<dt><a name="index-HOT_005fTEXT_005fSECTION_005fNAME"></a>Macro: <strong>HOT_TEXT_SECTION_NAME</strong></dt> +<dd><p>If defined, a C string constant for the name of the section containing most +frequently executed functions of the program. If not defined, GCC will provide +a default definition if the target supports named sections. +</p></dd></dl> + +<dl> +<dt><a name="index-UNLIKELY_005fEXECUTED_005fTEXT_005fSECTION_005fNAME"></a>Macro: <strong>UNLIKELY_EXECUTED_TEXT_SECTION_NAME</strong></dt> +<dd><p>If defined, a C string constant for the name of the section containing unlikely +executed functions in the program. +</p></dd></dl> + +<dl> +<dt><a name="index-DATA_005fSECTION_005fASM_005fOP"></a>Macro: <strong>DATA_SECTION_ASM_OP</strong></dt> +<dd><p>A C expression whose value is a string, including spacing, containing the +assembler operation to identify the following data as writable initialized +data. Normally <code>"\t.data"</code> is right. +</p></dd></dl> + +<dl> +<dt><a name="index-SDATA_005fSECTION_005fASM_005fOP"></a>Macro: <strong>SDATA_SECTION_ASM_OP</strong></dt> +<dd><p>If defined, a C expression whose value is a string, including spacing, +containing the assembler operation to identify the following data as +initialized, writable small data. +</p></dd></dl> + +<dl> +<dt><a name="index-READONLY_005fDATA_005fSECTION_005fASM_005fOP"></a>Macro: <strong>READONLY_DATA_SECTION_ASM_OP</strong></dt> +<dd><p>A C expression whose value is a string, including spacing, containing the +assembler operation to identify the following data as read-only initialized +data. +</p></dd></dl> + +<dl> +<dt><a name="index-BSS_005fSECTION_005fASM_005fOP"></a>Macro: <strong>BSS_SECTION_ASM_OP</strong></dt> +<dd><p>If defined, a C expression whose value is a string, including spacing, +containing the assembler operation to identify the following data as +uninitialized global data. If not defined, and +<code>ASM_OUTPUT_ALIGNED_BSS</code> not defined, +uninitialized global data will be output in the data section if +<samp>-fno-common</samp> is passed, otherwise <code>ASM_OUTPUT_COMMON</code> will be +used. +</p></dd></dl> + +<dl> +<dt><a name="index-SBSS_005fSECTION_005fASM_005fOP"></a>Macro: <strong>SBSS_SECTION_ASM_OP</strong></dt> +<dd><p>If defined, a C expression whose value is a string, including spacing, +containing the assembler operation to identify the following data as +uninitialized, writable small data. +</p></dd></dl> + +<dl> +<dt><a name="index-TLS_005fCOMMON_005fASM_005fOP"></a>Macro: <strong>TLS_COMMON_ASM_OP</strong></dt> +<dd><p>If defined, a C expression whose value is a string containing the +assembler operation to identify the following data as thread-local +common data. The default is <code>".tls_common"</code>. +</p></dd></dl> + +<dl> +<dt><a name="index-TLS_005fSECTION_005fASM_005fFLAG"></a>Macro: <strong>TLS_SECTION_ASM_FLAG</strong></dt> +<dd><p>If defined, a C expression whose value is a character constant +containing the flag used to mark a section as a TLS section. The +default is <code>'T'</code>. +</p></dd></dl> + +<dl> +<dt><a name="index-INIT_005fSECTION_005fASM_005fOP"></a>Macro: <strong>INIT_SECTION_ASM_OP</strong></dt> +<dd><p>If defined, a C expression whose value is a string, including spacing, +containing the assembler operation to identify the following data as +initialization code. If not defined, GCC will assume such a section does +not exist. This section has no corresponding <code>init_section</code> +variable; it is used entirely in runtime code. +</p></dd></dl> + +<dl> +<dt><a name="index-FINI_005fSECTION_005fASM_005fOP"></a>Macro: <strong>FINI_SECTION_ASM_OP</strong></dt> +<dd><p>If defined, a C expression whose value is a string, including spacing, +containing the assembler operation to identify the following data as +finalization code. If not defined, GCC will assume such a section does +not exist. This section has no corresponding <code>fini_section</code> +variable; it is used entirely in runtime code. +</p></dd></dl> + +<dl> +<dt><a name="index-INIT_005fARRAY_005fSECTION_005fASM_005fOP"></a>Macro: <strong>INIT_ARRAY_SECTION_ASM_OP</strong></dt> +<dd><p>If defined, a C expression whose value is a string, including spacing, +containing the assembler operation to identify the following data as +part of the <code>.init_array</code> (or equivalent) section. If not +defined, GCC will assume such a section does not exist. Do not define +both this macro and <code>INIT_SECTION_ASM_OP</code>. +</p></dd></dl> + +<dl> +<dt><a name="index-FINI_005fARRAY_005fSECTION_005fASM_005fOP"></a>Macro: <strong>FINI_ARRAY_SECTION_ASM_OP</strong></dt> +<dd><p>If defined, a C expression whose value is a string, including spacing, +containing the assembler operation to identify the following data as +part of the <code>.fini_array</code> (or equivalent) section. If not +defined, GCC will assume such a section does not exist. Do not define +both this macro and <code>FINI_SECTION_ASM_OP</code>. +</p></dd></dl> + +<dl> +<dt><a name="index-MACH_005fDEP_005fSECTION_005fASM_005fFLAG"></a>Macro: <strong>MACH_DEP_SECTION_ASM_FLAG</strong></dt> +<dd><p>If defined, a C expression whose value is a character constant +containing the flag used to mark a machine-dependent section. This +corresponds to the <code>SECTION_MACH_DEP</code> section flag. +</p></dd></dl> + +<dl> +<dt><a name="index-CRT_005fCALL_005fSTATIC_005fFUNCTION"></a>Macro: <strong>CRT_CALL_STATIC_FUNCTION</strong> <em>(<var>section_op</var>, <var>function</var>)</em></dt> +<dd><p>If defined, an ASM statement that switches to a different section +via <var>section_op</var>, calls <var>function</var>, and switches back to +the text section. This is used in <samp>crtstuff.c</samp> if +<code>INIT_SECTION_ASM_OP</code> or <code>FINI_SECTION_ASM_OP</code> to calls +to initialization and finalization functions from the init and fini +sections. By default, this macro uses a simple function call. Some +ports need hand-crafted assembly code to avoid dependencies on +registers initialized in the function prologue or to ensure that +constant pools don’t end up too far way in the text section. +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fLIBGCC_005fSDATA_005fSECTION"></a>Macro: <strong>TARGET_LIBGCC_SDATA_SECTION</strong></dt> +<dd><p>If defined, a string which names the section into which small +variables defined in crtstuff and libgcc should go. This is useful +when the target has options for optimizing access to small data, and +you want the crtstuff and libgcc routines to be conservative in what +they expect of your application yet liberal in what your application +expects. For example, for targets with a <code>.sdata</code> section (like +MIPS), you could compile crtstuff with <code>-G 0</code> so that it doesn’t +require small data support from your application, but use this macro +to put small data into <code>.sdata</code> so that your application can +access these variables whether it uses small data or not. +</p></dd></dl> + +<dl> +<dt><a name="index-FORCE_005fCODE_005fSECTION_005fALIGN"></a>Macro: <strong>FORCE_CODE_SECTION_ALIGN</strong></dt> +<dd><p>If defined, an ASM statement that aligns a code section to some +arbitrary boundary. This is used to force all fragments of the +<code>.init</code> and <code>.fini</code> sections to have to same alignment +and thus prevent the linker from having to add any padding. +</p></dd></dl> + +<dl> +<dt><a name="index-JUMP_005fTABLES_005fIN_005fTEXT_005fSECTION"></a>Macro: <strong>JUMP_TABLES_IN_TEXT_SECTION</strong></dt> +<dd><p>Define this macro to be an expression with a nonzero value if jump +tables (for <code>tablejump</code> insns) should be output in the text +section, along with the assembler instructions. Otherwise, the +readonly data section is used. +</p> +<p>This macro is irrelevant if there is no separate readonly data section. +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fASM_005fINIT_005fSECTIONS"></a>Target Hook: <em>void</em> <strong>TARGET_ASM_INIT_SECTIONS</strong> <em>(void)</em></dt> +<dd><p>Define this hook if you need to do something special to set up the +<samp>varasm.cc</samp> sections, or if your target has some special sections +of its own that you need to create. +</p> +<p>GCC calls this hook after processing the command line, but before writing +any assembly code, and before calling any of the section-returning hooks +described below. +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fASM_005fRELOC_005fRW_005fMASK"></a>Target Hook: <em>int</em> <strong>TARGET_ASM_RELOC_RW_MASK</strong> <em>(void)</em></dt> +<dd><p>Return a mask describing how relocations should be treated when +selecting sections. Bit 1 should be set if global relocations +should be placed in a read-write section; bit 0 should be set if +local relocations should be placed in a read-write section. +</p> +<p>The default version of this function returns 3 when <samp>-fpic</samp> +is in effect, and 0 otherwise. The hook is typically redefined +when the target cannot support (some kinds of) dynamic relocations +in read-only sections even in executables. +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fASM_005fGENERATE_005fPIC_005fADDR_005fDIFF_005fVEC"></a>Target Hook: <em>bool</em> <strong>TARGET_ASM_GENERATE_PIC_ADDR_DIFF_VEC</strong> <em>(void)</em></dt> +<dd><p>Return true to generate ADDR_DIF_VEC table +or false to generate ADDR_VEC table for jumps in case of -fPIC. +</p> +<p>The default version of this function returns true if flag_pic +equals true and false otherwise +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fASM_005fSELECT_005fSECTION"></a>Target Hook: <em>section *</em> <strong>TARGET_ASM_SELECT_SECTION</strong> <em>(tree <var>exp</var>, int <var>reloc</var>, unsigned HOST_WIDE_INT <var>align</var>)</em></dt> +<dd><p>Return the section into which <var>exp</var> should be placed. You can +assume that <var>exp</var> is either a <code>VAR_DECL</code> node or a constant of +some sort. <var>reloc</var> indicates whether the initial value of <var>exp</var> +requires link-time relocations. Bit 0 is set when variable contains +local relocations only, while bit 1 is set for global relocations. +<var>align</var> is the constant alignment in bits. +</p> +<p>The default version of this function takes care of putting read-only +variables in <code>readonly_data_section</code>. +</p> +<p>See also <var>USE_SELECT_SECTION_FOR_FUNCTIONS</var>. +</p></dd></dl> + +<dl> +<dt><a name="index-USE_005fSELECT_005fSECTION_005fFOR_005fFUNCTIONS"></a>Macro: <strong>USE_SELECT_SECTION_FOR_FUNCTIONS</strong></dt> +<dd><p>Define this macro if you wish TARGET_ASM_SELECT_SECTION to be called +for <code>FUNCTION_DECL</code>s as well as for variables and constants. +</p> +<p>In the case of a <code>FUNCTION_DECL</code>, <var>reloc</var> will be zero if the +function has been determined to be likely to be called, and nonzero if +it is unlikely to be called. +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fASM_005fUNIQUE_005fSECTION"></a>Target Hook: <em>void</em> <strong>TARGET_ASM_UNIQUE_SECTION</strong> <em>(tree <var>decl</var>, int <var>reloc</var>)</em></dt> +<dd><p>Build up a unique section name, expressed as a <code>STRING_CST</code> node, +and assign it to ‘<samp>DECL_SECTION_NAME (<var>decl</var>)</samp>’. +As with <code>TARGET_ASM_SELECT_SECTION</code>, <var>reloc</var> indicates whether +the initial value of <var>exp</var> requires link-time relocations. +</p> +<p>The default version of this function appends the symbol name to the +ELF section name that would normally be used for the symbol. For +example, the function <code>foo</code> would be placed in <code>.text.foo</code>. +Whatever the actual target object format, this is often good enough. +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fASM_005fFUNCTION_005fRODATA_005fSECTION"></a>Target Hook: <em>section *</em> <strong>TARGET_ASM_FUNCTION_RODATA_SECTION</strong> <em>(tree <var>decl</var>, bool <var>relocatable</var>)</em></dt> +<dd><p>Return the readonly data or reloc readonly data section associated with +‘<samp>DECL_SECTION_NAME (<var>decl</var>)</samp>’. <var>relocatable</var> selects the latter +over the former. +The default version of this function selects <code>.gnu.linkonce.r.name</code> if +the function’s section is <code>.gnu.linkonce.t.name</code>, <code>.rodata.name</code> +or <code>.data.rel.ro.name</code> if function is in <code>.text.name</code>, and +the normal readonly-data or reloc readonly data section otherwise. +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fASM_005fMERGEABLE_005fRODATA_005fPREFIX"></a>Target Hook: <em>const char *</em> <strong>TARGET_ASM_MERGEABLE_RODATA_PREFIX</strong></dt> +<dd><p>Usually, the compiler uses the prefix <code>".rodata"</code> to construct +section names for mergeable constant data. Define this macro to override +the string if a different section name should be used. +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fASM_005fTM_005fCLONE_005fTABLE_005fSECTION"></a>Target Hook: <em>section *</em> <strong>TARGET_ASM_TM_CLONE_TABLE_SECTION</strong> <em>(void)</em></dt> +<dd><p>Return the section that should be used for transactional memory clone +tables. +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fASM_005fSELECT_005fRTX_005fSECTION"></a>Target Hook: <em>section *</em> <strong>TARGET_ASM_SELECT_RTX_SECTION</strong> <em>(machine_mode <var>mode</var>, rtx <var>x</var>, unsigned HOST_WIDE_INT <var>align</var>)</em></dt> +<dd><p>Return the section into which a constant <var>x</var>, of mode <var>mode</var>, +should be placed. You can assume that <var>x</var> is some kind of +constant in RTL. The argument <var>mode</var> is redundant except in the +case of a <code>const_int</code> rtx. <var>align</var> is the constant alignment +in bits. +</p> +<p>The default version of this function takes care of putting symbolic +constants in <code>flag_pic</code> mode in <code>data_section</code> and everything +else in <code>readonly_data_section</code>. +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fMANGLE_005fDECL_005fASSEMBLER_005fNAME"></a>Target Hook: <em>tree</em> <strong>TARGET_MANGLE_DECL_ASSEMBLER_NAME</strong> <em>(tree <var>decl</var>, tree <var>id</var>)</em></dt> +<dd><p>Define this hook if you need to postprocess the assembler name generated +by target-independent code. The <var>id</var> provided to this hook will be +the computed name (e.g., the macro <code>DECL_NAME</code> of the <var>decl</var> in C, +or the mangled name of the <var>decl</var> in C++). The return value of the +hook is an <code>IDENTIFIER_NODE</code> for the appropriate mangled name on +your target system. The default implementation of this hook just +returns the <var>id</var> provided. +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fENCODE_005fSECTION_005fINFO"></a>Target Hook: <em>void</em> <strong>TARGET_ENCODE_SECTION_INFO</strong> <em>(tree <var>decl</var>, rtx <var>rtl</var>, int <var>new_decl_p</var>)</em></dt> +<dd><p>Define this hook if references to a symbol or a constant must be +treated differently depending on something about the variable or +function named by the symbol (such as what section it is in). +</p> +<p>The hook is executed immediately after rtl has been created for +<var>decl</var>, which may be a variable or function declaration or +an entry in the constant pool. In either case, <var>rtl</var> is the +rtl in question. Do <em>not</em> use <code>DECL_RTL (<var>decl</var>)</code> +in this hook; that field may not have been initialized yet. +</p> +<p>In the case of a constant, it is safe to assume that the rtl is +a <code>mem</code> whose address is a <code>symbol_ref</code>. Most decls +will also have this form, but that is not guaranteed. Global +register variables, for instance, will have a <code>reg</code> for their +rtl. (Normally the right thing to do with such unusual rtl is +leave it alone.) +</p> +<p>The <var>new_decl_p</var> argument will be true if this is the first time +that <code>TARGET_ENCODE_SECTION_INFO</code> has been invoked on this decl. It will +be false for subsequent invocations, which will happen for duplicate +declarations. Whether or not anything must be done for the duplicate +declaration depends on whether the hook examines <code>DECL_ATTRIBUTES</code>. +<var>new_decl_p</var> is always true when the hook is called for a constant. +</p> +<a name="index-SYMBOL_005fREF_005fFLAG_002c-in-TARGET_005fENCODE_005fSECTION_005fINFO"></a> +<p>The usual thing for this hook to do is to record flags in the +<code>symbol_ref</code>, using <code>SYMBOL_REF_FLAG</code> or <code>SYMBOL_REF_FLAGS</code>. +Historically, the name string was modified if it was necessary to +encode more than one bit of information, but this practice is now +discouraged; use <code>SYMBOL_REF_FLAGS</code>. +</p> +<p>The default definition of this hook, <code>default_encode_section_info</code> +in <samp>varasm.cc</samp>, sets a number of commonly-useful bits in +<code>SYMBOL_REF_FLAGS</code>. Check whether the default does what you need +before overriding it. +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fSTRIP_005fNAME_005fENCODING"></a>Target Hook: <em>const char *</em> <strong>TARGET_STRIP_NAME_ENCODING</strong> <em>(const char *<var>name</var>)</em></dt> +<dd><p>Decode <var>name</var> and return the real name part, sans +the characters that <code>TARGET_ENCODE_SECTION_INFO</code> +may have added. +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fIN_005fSMALL_005fDATA_005fP"></a>Target Hook: <em>bool</em> <strong>TARGET_IN_SMALL_DATA_P</strong> <em>(const_tree <var>exp</var>)</em></dt> +<dd><p>Returns true if <var>exp</var> should be placed into a “small data” section. +The default version of this hook always returns false. +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fHAVE_005fSRODATA_005fSECTION"></a>Target Hook: <em>bool</em> <strong>TARGET_HAVE_SRODATA_SECTION</strong></dt> +<dd><p>Contains the value true if the target places read-only +“small data” into a separate section. The default value is false. +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fPROFILE_005fBEFORE_005fPROLOGUE"></a>Target Hook: <em>bool</em> <strong>TARGET_PROFILE_BEFORE_PROLOGUE</strong> <em>(void)</em></dt> +<dd><p>It returns true if target wants profile code emitted before prologue. +</p> +<p>The default version of this hook use the target macro +<code>PROFILE_BEFORE_PROLOGUE</code>. +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fBINDS_005fLOCAL_005fP"></a>Target Hook: <em>bool</em> <strong>TARGET_BINDS_LOCAL_P</strong> <em>(const_tree <var>exp</var>)</em></dt> +<dd><p>Returns true if <var>exp</var> names an object for which name resolution +rules must resolve to the current “module” (dynamic shared library +or executable image). +</p> +<p>The default version of this hook implements the name resolution rules +for ELF, which has a looser model of global name binding than other +currently supported object file formats. +</p></dd></dl> + +<dl> +<dt><a name="index-TARGET_005fHAVE_005fTLS"></a>Target Hook: <em>bool</em> <strong>TARGET_HAVE_TLS</strong></dt> +<dd><p>Contains the value true if the target supports thread-local storage. +The default value is false. +</p></dd></dl> + + +<hr> +<div class="header"> +<p> +Next: <a href="PIC.html#PIC" accesskey="n" rel="next">PIC</a>, Previous: <a href="Scheduling.html#Scheduling" accesskey="p" rel="previous">Scheduling</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> |