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This is about outputting labels.
A C statement (sans semicolon) to output to the stdio stream stream the assembler definition of a label named name. Use the expression
assemble_name (
stream,
name)
to output the name itself; before and after that, output the additional assembler syntax for defining the name, and a newline. A default definition of this macro is provided which is correct for most systems.
Identical to
ASM_OUTPUT_LABEL
, except that name is known to refer to a compiler-generated label. The default definition usesassemble_name_raw
, which is likeassemble_name
except that it is more efficient.
A C string containing the appropriate assembler directive to specify the size of a symbol, without any arguments. On systems that use ELF, the default (in config/elfos.h) is `"\t.size\t"'; on other systems, the default is not to define this macro.
Define this macro only if it is correct to use the default definitions of
ASM_OUTPUT_SIZE_DIRECTIVE
andASM_OUTPUT_MEASURED_SIZE
for your system. If you need your own custom definitions of those macros, or if you do not need explicit symbol sizes at all, do not define this macro.
A C statement (sans semicolon) to output to the stdio stream stream a directive telling the assembler that the size of the symbol name is size. size is a
HOST_WIDE_INT
. If you defineSIZE_ASM_OP
, a default definition of this macro is provided.
A C statement (sans semicolon) to output to the stdio stream stream a directive telling the assembler to calculate the size of the symbol name by subtracting its address from the current address.
If you define
SIZE_ASM_OP
, a default definition of this macro is provided. The default assumes that the assembler recognizes a special `.' symbol as referring to the current address, and can calculate the difference between this and another symbol. If your assembler does not recognize `.' or cannot do calculations with it, you will need to redefineASM_OUTPUT_MEASURED_SIZE
to use some other technique.
A C string containing the appropriate assembler directive to specify the type of a symbol, without any arguments. On systems that use ELF, the default (in config/elfos.h) is `"\t.type\t"'; on other systems, the default is not to define this macro.
Define this macro only if it is correct to use the default definition of
ASM_OUTPUT_TYPE_DIRECTIVE
for your system. If you need your own custom definition of this macro, or if you do not need explicit symbol types at all, do not define this macro.
A C string which specifies (using
printf
syntax) the format of the second operand toTYPE_ASM_OP
. On systems that use ELF, the default (in config/elfos.h) is `"@%s"'; on other systems, the default is not to define this macro.Define this macro only if it is correct to use the default definition of
ASM_OUTPUT_TYPE_DIRECTIVE
for your system. If you need your own custom definition of this macro, or if you do not need explicit symbol types at all, do not define this macro.
A C statement (sans semicolon) to output to the stdio stream stream a directive telling the assembler that the type of the symbol name is type. type is a C string; currently, that string is always either `"function"' or `"object"', but you should not count on this.
If you define
TYPE_ASM_OP
andTYPE_OPERAND_FMT
, a default definition of this macro is provided.
A C statement (sans semicolon) to output to the stdio stream stream any text necessary for declaring the name name of a function which is being defined. This macro is responsible for outputting the label definition (perhaps using
ASM_OUTPUT_LABEL
). The argument decl is theFUNCTION_DECL
tree node representing the function.If this macro is not defined, then the function name is defined in the usual manner as a label (by means of
ASM_OUTPUT_LABEL
).You may wish to use
ASM_OUTPUT_TYPE_DIRECTIVE
in the definition of this macro.
A C statement (sans semicolon) to output to the stdio stream stream any text necessary for declaring the size of a function which is being defined. The argument name is the name of the function. The argument decl is the
FUNCTION_DECL
tree node representing the function.If this macro is not defined, then the function size is not defined.
You may wish to use
ASM_OUTPUT_MEASURED_SIZE
in the definition of this macro.
A C statement (sans semicolon) to output to the stdio stream stream any text necessary for declaring the name name of an initialized variable which is being defined. This macro must output the label definition (perhaps using
ASM_OUTPUT_LABEL
). The argument decl is theVAR_DECL
tree node representing the variable.If this macro is not defined, then the variable name is defined in the usual manner as a label (by means of
ASM_OUTPUT_LABEL
).You may wish to use
ASM_OUTPUT_TYPE_DIRECTIVE
and/orASM_OUTPUT_SIZE_DIRECTIVE
in the definition of this macro.
A C statement (sans semicolon) to output to the stdio stream stream any text necessary for declaring the name name of a constant which is being defined. This macro is responsible for outputting the label definition (perhaps using
ASM_OUTPUT_LABEL
). The argument exp is the value of the constant, and size is the size of the constant in bytes. name will be an internal label.If this macro is not defined, then the name is defined in the usual manner as a label (by means of
ASM_OUTPUT_LABEL
).You may wish to use
ASM_OUTPUT_TYPE_DIRECTIVE
in the definition of this macro.
A C statement (sans semicolon) to output to the stdio stream stream any text necessary for claiming a register regno for a global variable decl with name name.
If you don't define this macro, that is equivalent to defining it to do nothing.
A C statement (sans semicolon) to finish up declaring a variable name once the compiler has processed its initializer fully and thus has had a chance to determine the size of an array when controlled by an initializer. This is used on systems where it's necessary to declare something about the size of the object.
If you don't define this macro, that is equivalent to defining it to do nothing.
You may wish to use
ASM_OUTPUT_SIZE_DIRECTIVE
and/orASM_OUTPUT_MEASURED_SIZE
in the definition of this macro.
This target hook is a function to output to the stdio stream stream some commands that will make the label name global; that is, available for reference from other files.
The default implementation relies on a proper definition of
GLOBAL_ASM_OP
.
A C statement (sans semicolon) to output to the stdio stream stream some commands that will make the label name weak; that is, available for reference from other files but only used if no other definition is available. Use the expression
assemble_name (
stream,
name)
to output the name itself; before and after that, output the additional assembler syntax for making that name weak, and a newline.If you don't define this macro or
ASM_WEAKEN_DECL
, GCC will not support weak symbols and you should not define theSUPPORTS_WEAK
macro.
Combines (and replaces) the function of
ASM_WEAKEN_LABEL
andASM_OUTPUT_WEAK_ALIAS
, allowing access to the associated function or variable decl. If value is notNULL
, this C statement should output to the stdio stream stream assembler code which defines (equates) the weak symbol name to have the value value. If value isNULL
, it should output commands to make name weak.
Outputs a directive that enables name to be used to refer to symbol value with weak-symbol semantics.
decl
is the declaration ofname
.
A C expression which evaluates to true if the target supports weak symbols.
If you don't define this macro, defaults.h provides a default definition. If either
ASM_WEAKEN_LABEL
orASM_WEAKEN_DECL
is defined, the default definition is `1'; otherwise, it is `0'. Define this macro if you want to control weak symbol support with a compiler flag such as -melf.
A C statement (sans semicolon) to mark decl to be emitted as a public symbol such that extra copies in multiple translation units will be discarded by the linker. Define this macro if your object file format provides support for this concept, such as the `COMDAT' section flags in the Microsoft Windows PE/COFF format, and this support requires changes to decl, such as putting it in a separate section.
A C expression which evaluates to true if the target supports one-only semantics.
If you don't define this macro, varasm.c provides a default definition. If
MAKE_DECL_ONE_ONLY
is defined, the default definition is `1'; otherwise, it is `0'. Define this macro if you want to control one-only symbol support with a compiler flag, or if setting theDECL_ONE_ONLY
flag is enough to mark a declaration to be emitted as one-only.
This target hook is a function to output to asm_out_file some commands that will make the symbol(s) associated with decl have hidden, protected or internal visibility as specified by visibility.
A C expression that evaluates to true if the target's linker expects that weak symbols do not appear in a static archive's table of contents. The default is
0
.Leaving weak symbols out of an archive's table of contents means that, if a symbol will only have a definition in one translation unit and will have undefined references from other translation units, that symbol should not be weak. Defining this macro to be nonzero will thus have the effect that certain symbols that would normally be weak (explicit template instantiations, and vtables for polymorphic classes with noninline key methods) will instead be nonweak.
The C++ ABI requires this macro to be zero. Define this macro for targets where full C++ ABI compliance is impossible and where linker restrictions require weak symbols to be left out of a static archive's table of contents.
A C statement (sans semicolon) to output to the stdio stream stream any text necessary for declaring the name of an external symbol named name which is referenced in this compilation but not defined. The value of decl is the tree node for the declaration.
This macro need not be defined if it does not need to output anything. The GNU assembler and most Unix assemblers don't require anything.
This target hook is a function to output to asm_out_file an assembler pseudo-op to declare a library function name external. The name of the library function is given by symref, which is a
symbol_ref
.
This target hook is a function to output to asm_out_file an assembler directive to annotate used symbol. Darwin target use .no_dead_code_strip directive.
A C statement (sans semicolon) to output to the stdio stream stream a reference in assembler syntax to a label named name. This should add `_' to the front of the name, if that is customary on your operating system, as it is in most Berkeley Unix systems. This macro is used in
assemble_name
.
A C statement (sans semicolon) to output a reference to
SYMBOL_REF
sym. If not defined,assemble_name
will be used to output the name of the symbol. This macro may be used to modify the way a symbol is referenced depending on information encoded byTARGET_ENCODE_SECTION_INFO
.
A C statement (sans semicolon) to output a reference to buf, the result of
ASM_GENERATE_INTERNAL_LABEL
. If not defined,assemble_name
will be used to output the name of the symbol. This macro is not used byoutput_asm_label
, or the%l
specifier that calls it; the intention is that this macro should be set when it is necessary to output a label differently when its address is being taken.
A function to output to the stdio stream stream a label whose name is made from the string prefix and the number labelno.
It is absolutely essential that these labels be distinct from the labels used for user-level functions and variables. Otherwise, certain programs will have name conflicts with internal labels.
It is desirable to exclude internal labels from the symbol table of the object file. Most assemblers have a naming convention for labels that should be excluded; on many systems, the letter `L' at the beginning of a label has this effect. You should find out what convention your system uses, and follow it.
The default version of this function utilizes
ASM_GENERATE_INTERNAL_LABEL
.
A C statement to output to the stdio stream stream a debug info label whose name is made from the string prefix and the number num. This is useful for VLIW targets, where debug info labels may need to be treated differently than branch target labels. On some systems, branch target labels must be at the beginning of instruction bundles, but debug info labels can occur in the middle of instruction bundles.
If this macro is not defined, then
(*targetm.asm_out.internal_label)
will be used.
A C statement to store into the string string a label whose name is made from the string prefix and the number num.
This string, when output subsequently by
assemble_name
, should produce the output that(*targetm.asm_out.internal_label)
would produce with the same prefix and num.If the string begins with `*', then
assemble_name
will output the rest of the string unchanged. It is often convenient forASM_GENERATE_INTERNAL_LABEL
to use `*' in this way. If the string doesn't start with `*', thenASM_OUTPUT_LABELREF
gets to output the string, and may change it. (Of course,ASM_OUTPUT_LABELREF
is also part of your machine description, so you should know what it does on your machine.)
A C expression to assign to outvar (which is a variable of type
char *
) a newly allocated string made from the string name and the number number, with some suitable punctuation added. Usealloca
to get space for the string.The string will be used as an argument to
ASM_OUTPUT_LABELREF
to produce an assembler label for an internal static variable whose name is name. Therefore, the string must be such as to result in valid assembler code. The argument number is different each time this macro is executed; it prevents conflicts between similarly-named internal static variables in different scopes.Ideally this string should not be a valid C identifier, to prevent any conflict with the user's own symbols. Most assemblers allow periods or percent signs in assembler symbols; putting at least one of these between the name and the number will suffice.
If this macro is not defined, a default definition will be provided which is correct for most systems.
A C statement to output to the stdio stream stream assembler code which defines (equates) the symbol name to have the value value.
If
SET_ASM_OP
is defined, a default definition is provided which is correct for most systems.
A C statement to output to the stdio stream stream assembler code which defines (equates) the symbol whose tree node is decl_of_name to have the value of the tree node decl_of_value. This macro will be used in preference to `ASM_OUTPUT_DEF' if it is defined and if the tree nodes are available.
If
SET_ASM_OP
is defined, a default definition is provided which is correct for most systems.
A C statement that evaluates to true if the assembler code which defines (equates) the symbol whose tree node is decl_of_name to have the value of the tree node decl_of_value should be emitted near the end of the current compilation unit. The default is to not defer output of defines. This macro affects defines output by `ASM_OUTPUT_DEF' and `ASM_OUTPUT_DEF_FROM_DECLS'.
A C statement to output to the stdio stream stream assembler code which defines (equates) the weak symbol name to have the value value. If value is
NULL
, it defines name as an undefined weak symbol.Define this macro if the target only supports weak aliases; define
ASM_OUTPUT_DEF
instead if possible.
Define this macro to override the default assembler names used for Objective-C methods.
The default name is a unique method number followed by the name of the class (e.g. `_1_Foo'). For methods in categories, the name of the category is also included in the assembler name (e.g. `_1_Foo_Bar').
These names are safe on most systems, but make debugging difficult since the method's selector is not present in the name. Therefore, particular systems define other ways of computing names.
buf is an expression of type
char *
which gives you a buffer in which to store the name; its length is as long as class_name, cat_name and sel_name put together, plus 50 characters extra.The argument is_inst specifies whether the method is an instance method or a class method; class_name is the name of the class; cat_name is the name of the category (or
NULL
if the method is not in a category); and sel_name is the name of the selector.On systems where the assembler can handle quoted names, you can use this macro to provide more human-readable names.
A C statement (sans semicolon) to output to the stdio stream stream commands to declare that the label name is an Objective-C class reference. This is only needed for targets whose linkers have special support for NeXT-style runtimes.
A C statement (sans semicolon) to output to the stdio stream stream commands to declare that the label name is an unresolved Objective-C class reference. This is only needed for targets whose linkers have special support for NeXT-style runtimes.