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137 lines
3.2 KiB
Plaintext
137 lines
3.2 KiB
Plaintext
@c Copyright (C) 2011-2014 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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@ifset GENERIC
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@page
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@node RL78-Dependent
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@chapter RL78 Dependent Features
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@end ifset
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@ifclear GENERIC
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@node Machine Dependencies
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@chapter RL78 Dependent Features
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@end ifclear
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@cindex RL78 support
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@menu
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* RL78-Opts:: RL78 Assembler Command Line Options
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* RL78-Modifiers:: Symbolic Operand Modifiers
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* RL78-Directives:: Assembler Directives
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* RL78-Syntax:: Syntax
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@end menu
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@node RL78-Opts
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@section RL78 Options
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@cindex options, RL78
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@cindex RL78 options
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@table @code
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@item relax
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Enable support for link-time relaxation.
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@item mg10
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Mark the generated binary as targeting the G10 variant of the RL78
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architecture.
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@item m32bit-doubles
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Mark the generated binary as one that uses 32-bits to hold the
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@code{double} floating point type. This is the default.
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@item m64bit-doubles
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Mark the generated binary as one that uses 64-bits to hold the
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@code{double} floating point type.
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@end table
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@node RL78-Modifiers
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@section Symbolic Operand Modifiers
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@cindex RL78 modifiers
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@cindex syntax, RL78
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The RL78 has three modifiers that adjust the relocations used by the
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linker:
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@table @code
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@item %lo16()
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When loading a 20-bit (or wider) address into registers, this modifier
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selects the 16 least significant bits.
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@smallexample
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movw ax,#%lo16(_sym)
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@end smallexample
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@item %hi16()
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When loading a 20-bit (or wider) address into registers, this modifier
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selects the 16 most significant bits.
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@smallexample
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movw ax,#%hi16(_sym)
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@end smallexample
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@item %hi8()
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When loading a 20-bit (or wider) address into registers, this modifier
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selects the 8 bits that would go into CS or ES (i.e. bits 23..16).
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@smallexample
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mov es, #%hi8(_sym)
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@end smallexample
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@end table
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@node RL78-Directives
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@section Assembler Directives
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@cindex assembler directives, RL78
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@cindex RL78 assembler directives
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In addition to the common directives, the RL78 adds these:
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@table @code
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@item .double
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Output a constant in ``double'' format, which is either a 32-bit
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or a 64-bit floating point value, depending upon the setting of the
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@option{-m32bit-doubles}|@option{-m64bit-doubles} command line
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option.
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@item .bss
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Select the BSS section.
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@item .3byte
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Output a constant value in a three byte format.
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@item .int
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@itemx .word
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Output a constant value in a four byte format.
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@end table
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@node RL78-Syntax
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@section Syntax for the RL78
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@menu
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* RL78-Chars:: Special Characters
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@end menu
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@node RL78-Chars
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@subsection Special Characters
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@cindex line comment character, RL78
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@cindex RL78 line comment character
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The presence of a @samp{;} appearing anywhere on a line indicates the
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start of a comment that extends to the end of that line.
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If a @samp{#} appears as the first character of a line then the whole
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line is treated as a comment, but in this case the line can also be a
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logical line number directive (@pxref{Comments}) or a preprocessor
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control command (@pxref{Preprocessing}).
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@cindex line separator, RL78
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@cindex statement separator, RL78
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@cindex RL78 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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