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105 lines
3.1 KiB
Plaintext
105 lines
3.1 KiB
Plaintext
@c Copyright (C) 2010-2014 Free Software Foundation, Inc.
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@c This is part of the GAS manual.
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@c For copying conditions, see the file as.texinfo.
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@node XSTORMY16-Dependent
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@chapter XStormy16 Dependent Features
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@cindex XStormy16 support
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@menu
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* XStormy16 Syntax:: Syntax
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* XStormy16 Directives:: Machine Directives
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* XStormy16 Opcodes:: Pseudo-Opcodes
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@end menu
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@node XStormy16 Syntax
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@section Syntax
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@menu
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* XStormy16-Chars:: Special Characters
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@end menu
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@node XStormy16-Chars
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@subsection Special Characters
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@cindex line comment character, XStormy16
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@cindex XStormy16 line comment character
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@samp{#} is the line comment character. If a @samp{#} appears as the
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first character of a line, the whole line is treated as a comment, but
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in this case the line can also be a logical line number directive
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(@pxref{Comments}) or a preprocessor control command
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(@pxref{Preprocessing}).
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@cindex comment character, XStormy16
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@cindex XStormy16 comment character
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A semicolon (@samp{;}) can be used to start a comment that extends
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from wherever the character appears on the line up to the end of the
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line.
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@cindex line separator, XStormy16
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@cindex statement separator, XStormy16
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@cindex XStormy16 line separator
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The @samp{|} character can be used to separate statements on the same
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line.
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@node XStormy16 Directives
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@section XStormy16 Machine Directives
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@cindex machine directives, XStormy16
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@cindex XStormy16 machine directives
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@table @code
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@cindex @code{16bit_pointers} directive, XStormy16
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@item .16bit_pointers
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Like the @option{--16bit-pointers} command line option this directive
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indicates that the assembly code makes use of 16-bit pointers.
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@cindex @code{32bit_pointers} directive, XStormy16
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@item .32bit_pointers
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Like the @option{--32bit-pointers} command line option this directive
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indicates that the assembly code makes use of 32-bit pointers.
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@cindex @code{.no_pointers} directive, XStormy16
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@item .no_pointers
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Like the @option{--no-pointers} command line option this directive
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indicates that the assembly code does not makes use pointers.
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@end table
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@node XStormy16 Opcodes
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@section XStormy16 Pseudo-Opcodes
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@cindex XStormy16 pseudo-opcodes
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@cindex pseudo-opcodes for XStormy16
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@code{@value{AS}} implements all the standard XStormy16 opcodes.
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@code{@value{AS}} also implements the following pseudo ops:
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@table @code
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@cindex @code{@@lo} pseudo-op, XStormy16
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@item @@lo()
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Computes the lower 16 bits of the given expression and stores it into
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the immediate operand field of the given instruction. For example:
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@samp{add r6, @@lo(here - there)}
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computes the difference between the address of labels 'here' and
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'there', takes the lower 16 bits of this difference and adds it to
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register 6.
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@cindex @code{@@hi} pseudo-op, XStormy16
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@item @@hi()
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Computes the higher 16 bits of the given expression and stores it into
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the immediate operand field of the given instruction. For example:
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@samp{addc r7, @@hi(here - there)}
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computes the difference between the address of labels 'here' and
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'there', takes the upper 16 bits of this difference, shifts it down 16
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bits and then adds it, along with the carry bit, to the value in
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register 7.
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@end table
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