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@c Copyright 2009, 2011

@c Free Software Foundation, Inc.

@c This is part of the GAS manual.

@c For copying conditions, see the file as.texinfo.

@ifset GENERIC

@page

@node MicroBlaze-Dependent

@chapter MicroBlaze Dependent Features

@end ifset

@ifclear GENERIC

@node Machine Dependencies

@chapter MicroBlaze Dependent Features

@end ifclear

@cindex MicroBlaze architectures

The Xilinx MicroBlaze processor family includes several variants, all using

the same core instruction set.  This chapter covers features of the @sc{gnu}

assembler that are specific to the MicroBlaze architecture.  For details about

the MicroBlaze instruction set, please see the @cite{MicroBlaze Processor

Reference Guide (UG081)} available at www.xilinx.com.

@cindex MicroBlaze support

@menu

* MicroBlaze Directives::           Directives for MicroBlaze Processors.

* MicroBlaze Syntax::               Syntax for the MicroBlaze

@end menu

@node MicroBlaze Directives

@section Directives

@cindex MicroBlaze directives

A number of assembler directives are available for MicroBlaze.

@table @code

@item .data8 @var{expression},...

This directive is an alias for @code{.byte}. Each expression is assembled

into an eight-bit value.

@item .data16 @var{expression},...

This directive is an alias for @code{.hword}. Each expression is assembled

into an 16-bit value.

@item .data32 @var{expression},...

This directive is an alias for @code{.word}. Each expression is assembled

into an 32-bit value.

@item .ent @var{name}[,@var{label}]

This directive is an alias for @code{.func} denoting the start of function

@var{name} at (optional) @var{label}.

@item .end @var{name}[,@var{label}]

This directive is an alias for @code{.endfunc} denoting the end of function

@var{name}.

@item .gpword @var{label},...

This directive is an alias for @code{.rva}.  The resolved address of @var{label}

is stored in the data section.

@item .weakext @var{label}

Declare that @var{label} is a weak external symbol.

@item .rodata

Switch to .rodata section. Equivalent to @code{.section .rodata}

@item .sdata2

Switch to .sdata2 section. Equivalent to @code{.section .sdata2}

@item .sdata

Switch to .sdata section. Equivalent to @code{.section .sdata}

@item .bss

Switch to .bss section. Equivalent to @code{.section .bss}

@item .sbss

Switch to .sbss section. Equivalent to @code{.section .sbss}

@end table

@node MicroBlaze Syntax

@section Syntax for the MicroBlaze

@menu

* MicroBlaze-Chars::                Special Characters

@end menu

@node MicroBlaze-Chars

@subsection Special Characters

@cindex line comment character, MicroBlaze

@cindex MicroBlaze line comment character

The presence of a @samp{#} on a line indicates the start of a comment

that extends to the end of the current line.

If a @samp{#} appears as the first character of a line, the whole line

is treated as a comment, but in this case the line can also be a

logical line number directive (@pxref{Comments}) or a

preprocessor control command (@pxref{Preprocessing}).

@cindex line separator, MicroBlaze

@cindex statement separator, MicroBlaze

@cindex MicroBlaze line separator

The @samp{;} character can be used to separate statements on the same

line.