@end defmac
@defmac TRAMPOLINE_SECTION
-The name of a subroutine to switch to the section in which the
-trampoline template is to be placed (@pxref{Sections}). The default is
-a value of @samp{readonly_data_section}, which places the trampoline in
-the section containing read-only data.
+Return the section into which the trampoline template is to be placed
+(@pxref{Sections}). The default value is @code{readonly_data_section}.
@end defmac
@defmac TRAMPOLINE_SIZE
section}, which holds uninitialized data. Some systems have other kinds
of sections.
-The compiler must tell the assembler when to switch sections. These
-macros control what commands to output to tell the assembler this. You
-can also define additional sections.
+@file{varasm.c} provides several well-known sections, such as
+@code{text_section}, @code{data_section} and @code{bss_section}.
+The normal way of controlling a @code{@var{foo}_section} variable
+is to define the associated @code{@var{FOO}_SECTION_ASM_OP} macro,
+as described below. The macros are only read once, when @file{varasm.c}
+initializes itself, so their values must be run-time constants.
+They may however depend on command-line flags.
+
+@emph{Note:} Some run-time files, such @file{crtstuff.c}, also make
+use of the @code{@var{FOO}_SECTION_ASM_OP} macros, and expect them
+to be string literals.
+
+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} hook and use
+@code{get_unnamed_section} to set up the sections.
+
+You must always create a @code{text_section}, either by defining
+@code{TEXT_SECTION_ASM_OP} or by initializing @code{text_section}
+in @code{TARGET_ASM_INIT_SECTIONS}. The same is true of
+@code{data_section} and @code{DATA_SECTION_ASM_OP}. If you do not
+create a distinct @code{readonly_data_section}, the default is to
+reuse @code{text_section}.
+
+All the other @file{varasm.c} sections are optional, and are null
+if the target does not provide them.
@defmac TEXT_SECTION_ASM_OP
A C expression whose value is a string, including spacing, containing the
data. Normally @code{"\t.data"} is right.
@end defmac
+@defmac SDATA_SECTION_ASM_OP
+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.
+@end defmac
+
@defmac READONLY_DATA_SECTION_ASM_OP
A C expression whose value is a string, including spacing, containing the
assembler operation to identify the following data as read-only initialized
data.
@end defmac
-@defmac READONLY_DATA_SECTION
-A macro naming a function to call to switch to the proper section for
-read-only data. The default is to use @code{READONLY_DATA_SECTION_ASM_OP}
-if defined, else fall back to @code{text_section}.
-
-The most common definition will be @code{data_section}, if the target
-does not have a special read-only data section, and does not put data
-in the text section.
-@end defmac
-
@defmac BSS_SECTION_ASM_OP
If defined, a C expression whose value is a string, including spacing,
containing the assembler operation to identify the following data as
used.
@end defmac
+@defmac SBSS_SECTION_ASM_OP
+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.
+@end defmac
+
@defmac INIT_SECTION_ASM_OP
If defined, a C expression whose value is a string, including spacing,
containing the assembler operation to identify the following data as
and thus prevent the linker from having to add any padding.
@end defmac
-@findex in_text
-@findex in_data
-@defmac EXTRA_SECTIONS
-A list of names for sections other than the standard two, which are
-@code{in_text} and @code{in_data}. You need not define this macro
-on a system with no other sections (that GCC needs to use).
-@end defmac
-
-@findex text_section
-@findex data_section
-@defmac EXTRA_SECTION_FUNCTIONS
-One or more functions to be defined in @file{varasm.c}. These
-functions should do jobs analogous to those of @code{text_section} and
-@code{data_section}, for your additional sections. Do not define this
-macro if you do not define @code{EXTRA_SECTIONS}.
-@end defmac
-
@defmac JUMP_TABLES_IN_TEXT_SECTION
Define this macro to be an expression with a nonzero value if jump
tables (for @code{tablejump} insns) should be output in the text
This macro is irrelevant if there is no separate readonly data section.
@end defmac
-@deftypefn {Target Hook} void TARGET_ASM_SELECT_SECTION (tree @var{exp}, int @var{reloc}, unsigned HOST_WIDE_INT @var{align})
-Switches to the appropriate section for output of @var{exp}. You can
+@deftypefn {Target Hook} void TARGET_ASM_INIT_SECTIONS (void)
+Define this hook if you need to do something special to set up the
+@file{varasm.c} sections, or if your target has some special sections
+of its own that you need to create.
+
+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.
+@end deftypefn
+
+@deftypefn {Target Hook} {section *} TARGET_ASM_SELECT_SECTION (tree @var{exp}, int @var{reloc}, unsigned HOST_WIDE_INT @var{align})
+Return the section into which @var{exp} should be placed. You can
assume that @var{exp} is either a @code{VAR_DECL} node or a constant of
some sort. @var{reloc} indicates whether the initial value of @var{exp}
requires link-time relocations. Bit 0 is set when variable contains
local relocations only, while bit 1 is set for global relocations.
-Select the section by calling @code{data_section} or one of the
-alternatives for other sections. @var{align} is the constant alignment
-in bits.
+@var{align} is the constant alignment in bits.
The default version of this function takes care of putting read-only
variables in @code{readonly_data_section}.
Whatever the actual target object format, this is often good enough.
@end deftypefn
-@deftypefn {Target Hook} void TARGET_ASM_FUNCTION_RODATA_SECTION (tree @var{decl})
-Switches to a readonly data section associated with
+@deftypefn {Target Hook} {section *} TARGET_ASM_FUNCTION_RODATA_SECTION (tree @var{decl})
+Return the readonly data section associated with
@samp{DECL_SECTION_NAME (@var{decl})}.
-The default version of this function switches to @code{.gnu.linkonce.r.name}
-section if function's section is @code{.gnu.linkonce.t.name}, to
-@code{.rodata.name} if function is in @code{.text.name} section
-and otherwise switches to the normal readonly data section.
+The default version of this function selects @code{.gnu.linkonce.r.name} if
+the function's section is @code{.gnu.linkonce.t.name}, @code{.rodata.name}
+if function is in @code{.text.name}, and the normal readonly-data section
+otherwise.
@end deftypefn
-@deftypefn {Target Hook} void TARGET_ASM_SELECT_RTX_SECTION (enum machine_mode @var{mode}, rtx @var{x}, unsigned HOST_WIDE_INT @var{align})
-Switches to the appropriate section for output of constant pool entry
-@var{x} in @var{mode}. You can assume that @var{x} is some kind of
+@deftypefn {Target Hook} {section *} TARGET_ASM_SELECT_RTX_SECTION (enum machine_mode @var{mode}, rtx @var{x}, unsigned HOST_WIDE_INT @var{align})
+Return the section into which a constant @var{x}, of mode @var{mode},
+should be placed. You can assume that @var{x} is some kind of
constant in RTL@. The argument @var{mode} is redundant except in the
-case of a @code{const_int} rtx. Select the section by calling
-@code{readonly_data_section} or one of the alternatives for other
-sections. @var{align} is the constant alignment in bits.
+case of a @code{const_int} rtx. @var{align} is the constant alignment
+in bits.
The default version of this function takes care of putting symbolic
constants in @code{flag_pic} mode in @code{data_section} and everything
the target supports DWARF 2 frame unwind information.
@end defmac
-@deftypefn {Target Hook} void TARGET_ASM_EXCEPTION_SECTION ()
-If defined, a function that switches to the section in which the main
-exception table is to be placed (@pxref{Sections}). The default is a
-function that switches to a section named @code{.gcc_except_table} on
-machines that support named sections via
-@code{TARGET_ASM_NAMED_SECTION}, otherwise if @option{-fpic} or
-@option{-fPIC} is in effect, the @code{data_section}, otherwise the
-@code{readonly_data_section}.
-@end deftypefn
-
-@deftypefn {Target Hook} void TARGET_ASM_EH_FRAME_SECTION ()
-If defined, a function that switches to the section in which the DWARF 2
-frame unwind information to be placed (@pxref{Sections}). The default
-is a function that outputs a standard GAS section directive, if
-@code{EH_FRAME_SECTION_NAME} is defined, or else a data section
-directive followed by a synthetic label.
-@end deftypefn
-
@deftypevar {Target Hook} bool TARGET_TERMINATE_DW2_EH_FRAME_INFO
Contains the value true if the target should add a zero word onto the
end of a Dwarf-2 frame info section when used for exception handling.
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