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Document oword, do and reso

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Document oword and the associated do and reso pseudoinstructions.
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H. Peter Anvin 2007-09-18 13:45:12 -07:00
parent 41c9f6fde0
commit 0edc309505
1 changed files with 22 additions and 22 deletions
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doc/nasmdoc.src
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@ -1115,19 +1115,19 @@ indicate what size of \i{memory operand} it refers to.
\H{pseudop} \i{Pseudo-Instructions}
Pseudo-instructions are things which, though not real x86 machine
instructions, are used in the instruction field anyway because
that's the most convenient place to put them. The current
pseudo-instructions are \i\c{DB}, \i\c{DW}, \i\c{DD}, \i\c{DQ} and
\i\c{DT}, their \i{uninitialized} counterparts \i\c{RESB},
\i\c{RESW}, \i\c{RESD}, \i\c{RESQ} and \i\c{REST}, the \i\c{INCBIN}
instructions, are used in the instruction field anyway because that's
the most convenient place to put them. The current pseudo-instructions
are \i\c{DB}, \i\c{DW}, \i\c{DD}, \i\c{DQ}, \i\c{DT} and \i\c{DO};
their \i{uninitialized} counterparts \i\c{RESB}, \i\c{RESW},
\i\c{RESD}, \i\c{RESQ}, \i\c{REST} and \i\c{RESO}; the \i\c{INCBIN}
command, the \i\c{EQU} command, and the \i\c{TIMES} prefix.
\S{db} \c{DB} and friends: Declaring initialized Data
\i\c{DB}, \i\c{DW}, \i\c{DD}, \i\c{DQ} and \i\c{DT} are used, much
as in MASM, to declare initialized data in the output file. They can
be invoked in a wide range of ways:
\i\c{DB}, \i\c{DW}, \i\c{DD}, \i\c{DQ}, \i\c{DT} and \i\c{DO} are
used, much as in MASM, to declare initialized data in the output
file. They can be invoked in a wide range of ways:
\I{floating-point}\I{character constant}\I{string constant}
\c db 0x55 ; just the byte 0x55
@ -1144,20 +1144,20 @@ be invoked in a wide range of ways:
\c dq 1.234567e20 ; double-precision float
\c dt 1.234567e20 ; extended-precision float
\c{DT} does not accept \i{numeric constants} as operands.
\c{DT} and \c{DO} do not accept \i{numeric constants} as operands.
\S{resb} \c{RESB} and friends: Declaring \i{Uninitialized} Data
\i\c{RESB}, \i\c{RESW}, \i\c{RESD}, \i\c{RESQ} and \i\c{REST} are
designed to be used in the BSS section of a module: they declare
\e{uninitialized} storage space. Each takes a single operand, which
is the number of bytes, words, doublewords or whatever to reserve.
As stated in \k{qsother}, NASM does not support the MASM/TASM syntax
of reserving uninitialized space by writing \I\c{?}\c{DW ?} or
similar things: this is what it does instead. The operand to a
\c{RESB}-type pseudo-instruction is a \i\e{critical expression}: see
\k{crit}.
\i\c{RESB}, \i\c{RESW}, \i\c{RESD}, \i\c{RESQ}, \i\c{REST} and
\i\c{RESO} are designed to be used in the BSS section of a module:
they declare \e{uninitialized} storage space. Each takes a single
operand, which is the number of bytes, words, doublewords or whatever
to reserve. As stated in \k{qsother}, NASM does not support the
MASM/TASM syntax of reserving uninitialized space by writing
\I\c{?}\c{DW ?} or similar things: this is what it does instead. The
operand to a \c{RESB}-type pseudo-instruction is a \i\e{critical
expression}: see \k{crit}.
For example:
@ -1560,11 +1560,11 @@ invent one using the macro processor.
When assembling with the optimizer set to level 2 or higher (see
\k{opt-On}), NASM will use size specifiers (\c{BYTE}, \c{WORD},
\c{DWORD}, \c{QWORD}, or \c{TWORD}), but will give them the smallest
possible size. The keyword \c{STRICT} can be used to inhibit
\c{DWORD}, \c{QWORD}, \c{TWORD} or \c{OWORD}), but will give them the
smallest possible size. The keyword \c{STRICT} can be used to inhibit
optimization and force a particular operand to be emitted in the
specified size. For example, with the optimizer on, and in
\c{BITS 16} mode,
specified size. For example, with the optimizer on, and in \c{BITS 16}
mode,
\c push dword 33