-@c Copyright (C) 2000 Free Software Foundation, Inc.
+@c Copyright (C) 2000-2017 Free Software Foundation, Inc.
@c This is part of the GAS manual.
@c For copying conditions, see the file as.texinfo.
@ifset GENERIC
@ignore
@c FIXME: This is basically a stub for i860. There is tons more information
-that I will add later (jle@cygnus.com). The assembler is still being
-written. The i860 assembler that existed previously was never finished
-and doesn't even build. Further, its not BFD_ASSEMBLER and it doesn't
-do ELF (it doesn't do anything, but you get the point).
+that I will add later (jle@cygnus.com).
@end ignore
@cindex i860 support
@menu
+* Notes-i860:: i860 Notes
* Options-i860:: i860 Command-line Options
* Directives-i860:: i860 Machine Directives
* Opcodes for i860:: i860 Opcodes
+* Syntax of i860:: i860 Syntax
@end menu
-@node Options-i860
+@node Notes-i860
+@section i860 Notes
+This is a fairly complete i860 assembler which is compatible with the
+UNIX System V/860 Release 4 assembler. However, it does not currently
+support SVR4 PIC (i.e., @code{@@GOT, @@GOTOFF, @@PLT}).
+
+Like the SVR4/860 assembler, the output object format is ELF32. Currently,
+this is the only supported object format. If there is sufficient interest,
+other formats such as COFF may be implemented.
+Both the Intel and AT&T/SVR4 syntaxes are supported, with the latter
+being the default. One difference is that AT&T syntax requires the '%'
+prefix on register names while Intel syntax does not. Another difference
+is in the specification of relocatable expressions. The Intel syntax
+is @code{ha%expression} whereas the SVR4 syntax is @code{[expression]@@ha}
+(and similarly for the "l" and "h" selectors).
+@node Options-i860
@section i860 Command-line Options
-@subsection SVR4 compatibility options
+@subsection SVR4 compatibility options
@table @code
@item -V
Print assembler version.
@item -Qn
Ignored.
@end table
-@subsection Other options
+@subsection Other options
@table @code
@item -EL
Select little endian output (this is the default).
Select big endian output. Note that the i860 always reads instructions
as little endian data, so this option only effects data and not
instructions.
+@item -mwarn-expand
+Emit a warning message if any pseudo-instruction expansions occurred.
+For example, a @code{or} instruction with an immediate larger than 16-bits
+will be expanded into two instructions. This is a very undesirable feature to
+rely on, so this flag can help detect any code where it happens. One
+use of it, for instance, has been to find and eliminate any place
+where @code{gcc} may emit these pseudo-instructions.
+@item -mxp
+Enable support for the i860XP instructions and control registers. By default,
+this option is disabled so that only the base instruction set (i.e., i860XR)
+is supported.
+@item -mintel-syntax
+The i860 assembler defaults to AT&T/SVR4 syntax. This option enables the
+Intel syntax.
@end table
@node Directives-i860
default register is @code{r31}.
@end table
+The @code{.dual}, @code{.enddual}, and @code{.atmp} directives are available only in the Intel syntax mode.
+
+Both syntaxes allow for the standard @code{.align} directive. However,
+the Intel syntax additionally allows keywords for the alignment
+parameter: "@code{.align type}", where `type' is one of @code{.short}, @code{.long},
+@code{.quad}, @code{.single}, @code{.double} representing alignments of 2, 4,
+16, 4, and 8, respectively.
+
@node Opcodes for i860
@section i860 Opcodes
@cindex opcodes, i860
@cindex i860 opcodes
-All of the Intel i860 machine instructions are supported.
+All of the Intel i860XR and i860XP machine instructions are supported. Please see
+either @emph{i860 Microprocessor Programmer's Reference Manual} or @emph{i860 Microprocessor Architecture} for more information.
+@subsection Other instruction support (pseudo-instructions)
+For compatibility with some other i860 assemblers, a number of
+pseudo-instructions are supported. While these are supported, they are
+a very undesirable feature that should be avoided -- in particular, when
+they result in an expansion to multiple actual i860 instructions. Below
+are the pseudo-instructions that result in expansions.
+@itemize @bullet
+@item Load large immediate into general register:
+
+The pseudo-instruction @code{mov imm,%rn} (where the immediate does
+not fit within a signed 16-bit field) will be expanded into:
+@smallexample
+orh large_imm@@h,%r0,%rn
+or large_imm@@l,%rn,%rn
+@end smallexample
+@item Load/store with relocatable address expression:
+
+For example, the pseudo-instruction @code{ld.b addr_exp(%rx),%rn}
+will be expanded into:
+@smallexample
+orh addr_exp@@ha,%rx,%r31
+ld.l addr_exp@@l(%r31),%rn
+@end smallexample
+
+The analogous expansions apply to @code{ld.x, st.x, fld.x, pfld.x, fst.x}, and @code{pst.x} as well.
+@item Signed large immediate with add/subtract:
+
+If any of the arithmetic operations @code{adds, addu, subs, subu} are used
+with an immediate larger than 16-bits (signed), then they will be expanded.
+For instance, the pseudo-instruction @code{adds large_imm,%rx,%rn} expands to:
+@smallexample
+orh large_imm@@h,%r0,%r31
+or large_imm@@l,%r31,%r31
+adds %r31,%rx,%rn
+@end smallexample
+@item Unsigned large immediate with logical operations:
+
+Logical operations (@code{or, andnot, or, xor}) also result in expansions.
+The pseudo-instruction @code{or large_imm,%rx,%rn} results in:
+@smallexample
+orh large_imm@@h,%rx,%r31
+or large_imm@@l,%r31,%rn
+@end smallexample
+
+Similarly for the others, except for @code{and} which expands to:
+@smallexample
+andnot (-1 - large_imm)@@h,%rx,%r31
+andnot (-1 - large_imm)@@l,%r31,%rn
+@end smallexample
+@end itemize
+
+@node Syntax of i860
+@section i860 Syntax
+@menu
+* i860-Chars:: Special Characters
+@end menu
+
+@node i860-Chars
+@subsection Special Characters
+
+@cindex line comment character, i860
+@cindex i860 line comment character
+The presence of a @samp{#} appearing anywhere on a line indicates the
+start of a comment that extends to the end of that line.
-Some opcodes are processed beyond simply emitting a single corresponding
-instruction. For example, @samp{mov} and other instructions with larg
-displacements may be expanded into 2 or 3 instructions (FIXME: add details).
+If a @samp{#} appears as the first character of a line then 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, i860
+@cindex statement separator, i860
+@cindex i860 line separator
+The @samp{;} character can be used to separate statements on the same
+line.
projects / deliverable / binutils-gdb.git / blobdiff