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author | Victoria Mixon <victoria@cygnus> | 1995-11-10 19:28:36 +0000 |
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committer | Victoria Mixon <victoria@cygnus> | 1995-11-10 19:28:36 +0000 |
commit | 0e6886424144485e224723036e2ff8027442e6dc (patch) | |
tree | 05db557eb2347ebb5139d2eaaf8cdd436ed5c7ec | |
parent | b94ff92428b88d8315005a5ee956845ddf8d51a3 (diff) | |
download | gdb-0e6886424144485e224723036e2ff8027442e6dc.zip gdb-0e6886424144485e224723036e2ff8027442e6dc.tar.gz gdb-0e6886424144485e224723036e2ff8027442e6dc.tar.bz2 |
references to pesch@cygnus.com changed to doc@cygnus.com
-rw-r--r-- | gas/doc/c-a29k.texi | 14 | ||||
-rw-r--r-- | gas/doc/c-i960.texi | 298 | ||||
-rw-r--r-- | gas/doc/c-sparc.texi | 122 | ||||
-rw-r--r-- | gas/doc/c-vax.texi | 323 | ||||
-rw-r--r-- | gas/doc/gasp.texi | 4 |
5 files changed, 752 insertions, 9 deletions
diff --git a/gas/doc/c-a29k.texi b/gas/doc/c-a29k.texi index 771831a..4d115d8 100644 --- a/gas/doc/c-a29k.texi +++ b/gas/doc/c-a29k.texi @@ -116,8 +116,8 @@ The AMD 29K family uses @sc{ieee} floating-point numbers. @cindex machine directives, AMD 29K @cindex AMD 29K machine directives @table @code -@item .block @var{size} , @var{fill} @cindex @code{block} directive, AMD 29K +@item .block @var{size} , @var{fill} This directive emits @var{size} bytes, each of value @var{fill}. Both @var{size} and @var{fill} are absolute expressions. If the comma and @var{fill} are omitted, @var{fill} is assumed to be zero. @@ -127,13 +127,13 @@ In other versions of the @sc{gnu} assembler, this directive is called @end table @table @code -@item .cputype @cindex @code{cputype} directive, AMD 29K +@item .cputype This directive is ignored; it is accepted for compatibility with other AMD 29K assemblers. -@item .file @cindex @code{file} directive, AMD 29K +@item .file This directive is ignored; it is accepted for compatibility with other AMD 29K assemblers. @@ -142,25 +142,25 @@ AMD 29K assemblers. used for the directive called @code{.app-file} in the AMD 29K support. @end quotation -@item .line @cindex @code{line} directive, AMD 29K +@item .line This directive is ignored; it is accepted for compatibility with other AMD 29K assemblers. @ignore @c since we're ignoring .lsym... -@item .reg @var{symbol}, @var{expression} @cindex @code{reg} directive, AMD 29K +@item .reg @var{symbol}, @var{expression} @code{.reg} has the same effect as @code{.lsym}; @pxref{Lsym,,@code{.lsym}}. @end ignore -@item .sect @cindex @code{sect} directive, AMD 29K +@item .sect This directive is ignored; it is accepted for compatibility with other AMD 29K assemblers. -@item .use @var{section name} @cindex @code{use} directive, AMD 29K +@item .use @var{section name} Establishes the section and subsection for the following code; @var{section name} may be one of @code{.text}, @code{.data}, @code{.data1}, or @code{.lit}. With one of the first three @var{section diff --git a/gas/doc/c-i960.texi b/gas/doc/c-i960.texi new file mode 100644 index 0000000..31d720c --- /dev/null +++ b/gas/doc/c-i960.texi @@ -0,0 +1,298 @@ +@c Copyright (C) 1991, 1992, 1993, 1994, 1995 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 i960-Dependent +@chapter Intel 80960 Dependent Features +@end ifset +@ifclear GENERIC +@node Machine Dependencies +@chapter Intel 80960 Dependent Features +@end ifclear + +@cindex i960 support +@menu +* Options-i960:: i960 Command-line Options +* Floating Point-i960:: Floating Point +* Directives-i960:: i960 Machine Directives +* Opcodes for i960:: i960 Opcodes +@end menu + +@c FIXME! Add Syntax sec with discussion of bitfields here, at least so +@c long as they're not turned on for other machines than 960. + +@node Options-i960 + +@section i960 Command-line Options + +@cindex i960 options +@cindex options, i960 +@table @code + +@cindex i960 architecture options +@cindex architecture options, i960 +@cindex @code{-A} options, i960 +@item -ACA | -ACA_A | -ACB | -ACC | -AKA | -AKB | -AKC | -AMC +Select the 80960 architecture. Instructions or features not supported +by the selected architecture cause fatal errors. + +@samp{-ACA} is equivalent to @samp{-ACA_A}; @samp{-AKC} is equivalent to +@samp{-AMC}. Synonyms are provided for compatibility with other tools. + +If you do not specify any of these options, @code{@value{AS}} generates code +for any instruction or feature that is supported by @emph{some} version of the +960 (even if this means mixing architectures!). In principle, +@code{@value{AS}} attempts to deduce the minimal sufficient processor type if +none is specified; depending on the object code format, the processor type may +be recorded in the object file. If it is critical that the @code{@value{AS}} +output match a specific architecture, specify that architecture explicitly. + +@cindex @code{-b} option, i960 +@cindex branch recording, i960 +@cindex i960 branch recording +@item -b +Add code to collect information about conditional branches taken, for +later optimization using branch prediction bits. (The conditional branch +instructions have branch prediction bits in the CA, CB, and CC +architectures.) If @var{BR} represents a conditional branch instruction, +the following represents the code generated by the assembler when +@samp{-b} is specified: + +@smallexample + call @var{increment routine} + .word 0 # pre-counter +Label: @var{BR} + call @var{increment routine} + .word 0 # post-counter +@end smallexample + +The counter following a branch records the number of times that branch +was @emph{not} taken; the differenc between the two counters is the +number of times the branch @emph{was} taken. + +@cindex @code{gbr960}, i960 postprocessor +@cindex branch statistics table, i960 +A table of every such @code{Label} is also generated, so that the +external postprocessor @code{gbr960} (supplied by Intel) can locate all +the counters. This table is always labelled @samp{__BRANCH_TABLE__}; +this is a local symbol to permit collecting statistics for many separate +object files. The table is word aligned, and begins with a two-word +header. The first word, initialized to 0, is used in maintaining linked +lists of branch tables. The second word is a count of the number of +entries in the table, which follow immediately: each is a word, pointing +to one of the labels illustrated above. + +@c TEXI2ROFF-KILL +@ifinfo +@c END TEXI2ROFF-KILL +@example + +------------+------------+------------+ ... +------------+ + | | | | | | + | *NEXT | COUNT: N | *BRLAB 1 | | *BRLAB N | + | | | | | | + +------------+------------+------------+ ... +------------+ + + __BRANCH_TABLE__ layout +@end example +@c TEXI2ROFF-KILL +@end ifinfo +@need 2000 +@tex +\vskip 1pc +\line{\leftskip=0pt\hskip\tableindent +\boxit{2cm}{\tt *NEXT}\boxit{2cm}{\tt COUNT: \it N}\boxit{2cm}{\tt +*BRLAB 1}\ibox{1cm}{\quad\dots}\boxit{2cm}{\tt *BRLAB \it N}\hfil} +\centerline{\it {\tt \_\_BRANCH\_TABLE\_\_} layout} +@end tex +@c END TEXI2ROFF-KILL + +The first word of the header is used to locate multiple branch tables, +since each object file may contain one. Normally the links are +maintained with a call to an initialization routine, placed at the +beginning of each function in the file. The @sc{gnu} C compiler +generates these calls automatically when you give it a @samp{-b} option. +For further details, see the documentation of @samp{gbr960}. + +@cindex @code{-no-relax} option, i960 +@item -no-relax +Normally, Compare-and-Branch instructions with targets that require +displacements greater than 13 bits (or that have external targets) are +replaced with the corresponding compare (or @samp{chkbit}) and branch +instructions. You can use the @samp{-no-relax} option to specify that +@code{@value{AS}} should generate errors instead, if the target displacement +is larger than 13 bits. + +This option does not affect the Compare-and-Jump instructions; the code +emitted for them is @emph{always} adjusted when necessary (depending on +displacement size), regardless of whether you use @samp{-no-relax}. +@end table + +@node Floating Point-i960 +@section Floating Point + +@cindex floating point, i960 (@sc{ieee}) +@cindex i960 floating point (@sc{ieee}) +@code{@value{AS}} generates @sc{ieee} floating-point numbers for the directives +@samp{.float}, @samp{.double}, @samp{.extended}, and @samp{.single}. + +@node Directives-i960 +@section i960 Machine Directives + +@cindex machine directives, i960 +@cindex i960 machine directives + +@table @code +@cindex @code{bss} directive, i960 +@item .bss @var{symbol}, @var{length}, @var{align} +Reserve @var{length} bytes in the bss section for a local @var{symbol}, +aligned to the power of two specified by @var{align}. @var{length} and +@var{align} must be positive absolute expressions. This directive +differs from @samp{.lcomm} only in that it permits you to specify +an alignment. @xref{Lcomm,,@code{.lcomm}}. +@end table + +@table @code +@cindex @code{extended} directive, i96 +@item .extended @var{flonums} +@code{.extended} expects zero or more flonums, separated by commas; for +each flonum, @samp{.extended} emits an @sc{ieee} extended-format (80-bit) +floating-point number. + +@cindex @code{leafproc} directive, i960 +@item .leafproc @var{call-lab}, @var{bal-lab} +You can use the @samp{.leafproc} directive in conjunction with the +optimized @code{callj} instruction to enable faster calls of leaf +procedures. If a procedure is known to call no other procedures, you +may define an entry point that skips procedure prolog code (and that does +not depend on system-supplied saved context), and declare it as the +@var{bal-lab} using @samp{.leafproc}. If the procedure also has an +entry point that goes through the normal prolog, you can specify that +entry point as @var{call-lab}. + +A @samp{.leafproc} declaration is meant for use in conjunction with the +optimized call instruction @samp{callj}; the directive records the data +needed later to choose between converting the @samp{callj} into a +@code{bal} or a @code{call}. + +@var{call-lab} is optional; if only one argument is present, or if the +two arguments are identical, the single argument is assumed to be the +@code{bal} entry point. + +@cindex @code{sysproc} directive, i960 +@item .sysproc @var{name}, @var{index} +The @samp{.sysproc} directive defines a name for a system procedure. +After you define it using @samp{.sysproc}, you can use @var{name} to +refer to the system procedure identified by @var{index} when calling +procedures with the optimized call instruction @samp{callj}. + +Both arguments are required; @var{index} must be between 0 and 31 +(inclusive). +@end table + +@node Opcodes for i960 +@section i960 Opcodes + +@cindex opcodes, i960 +@cindex i960 opcodes +All Intel 960 machine instructions are supported; +@pxref{Options-i960,,i960 Command-line Options} for a discussion of +selecting the instruction subset for a particular 960 +architecture.@refill + +Some opcodes are processed beyond simply emitting a single corresponding +instruction: @samp{callj}, and Compare-and-Branch or Compare-and-Jump +instructions with target displacements larger than 13 bits. + +@menu +* callj-i960:: @code{callj} +* Compare-and-branch-i960:: Compare-and-Branch +@end menu + +@node callj-i960 +@subsection @code{callj} + +@cindex @code{callj}, i960 pseudo-opcode +@cindex i960 @code{callj} pseudo-opcode +You can write @code{callj} to have the assembler or the linker determine +the most appropriate form of subroutine call: @samp{call}, +@samp{bal}, or @samp{calls}. If the assembly source contains +enough information---a @samp{.leafproc} or @samp{.sysproc} directive +defining the operand---then @code{@value{AS}} translates the +@code{callj}; if not, it simply emits the @code{callj}, leaving it +for the linker to resolve. + +@node Compare-and-branch-i960 +@subsection Compare-and-Branch + +@cindex i960 compare/branch instructions +@cindex compare/branch instructions, i960 +The 960 architectures provide combined Compare-and-Branch instructions +that permit you to store the branch target in the lower 13 bits of the +instruction word itself. However, if you specify a branch target far +enough away that its address won't fit in 13 bits, the assembler can +either issue an error, or convert your Compare-and-Branch instruction +into separate instructions to do the compare and the branch. + +@cindex compare and jump expansions, i960 +@cindex i960 compare and jump expansions +Whether @code{@value{AS}} gives an error or expands the instruction depends +on two choices you can make: whether you use the @samp{-no-relax} option, +and whether you use a ``Compare and Branch'' instruction or a ``Compare +and Jump'' instruction. The ``Jump'' instructions are @emph{always} +expanded if necessary; the ``Branch'' instructions are expanded when +necessary @emph{unless} you specify @code{-no-relax}---in which case +@code{@value{AS}} gives an error instead. + +These are the Compare-and-Branch instructions, their ``Jump'' variants, +and the instruction pairs they may expand into: + +@c TEXI2ROFF-KILL +@ifinfo +@c END TEXI2ROFF-KILL +@example + Compare and + Branch Jump Expanded to + ------ ------ ------------ + bbc chkbit; bno + bbs chkbit; bo + cmpibe cmpije cmpi; be + cmpibg cmpijg cmpi; bg + cmpibge cmpijge cmpi; bge + cmpibl cmpijl cmpi; bl + cmpible cmpijle cmpi; ble + cmpibno cmpijno cmpi; bno + cmpibne cmpijne cmpi; bne + cmpibo cmpijo cmpi; bo + cmpobe cmpoje cmpo; be + cmpobg cmpojg cmpo; bg + cmpobge cmpojge cmpo; bge + cmpobl cmpojl cmpo; bl + cmpoble cmpojle cmpo; ble + cmpobne cmpojne cmpo; bne +@end example +@c TEXI2ROFF-KILL +@end ifinfo +@tex +\hskip\tableindent +\halign{\hfil {\tt #}\quad&\hfil {\tt #}\qquad&{\tt #}\hfil\cr +\omit{\hfil\it Compare and\hfil}\span\omit&\cr +{\it Branch}&{\it Jump}&{\it Expanded to}\cr + bbc& & chkbit; bno\cr + bbs& & chkbit; bo\cr + cmpibe& cmpije& cmpi; be\cr + cmpibg& cmpijg& cmpi; bg\cr + cmpibge& cmpijge& cmpi; bge\cr + cmpibl& cmpijl& cmpi; bl\cr + cmpible& cmpijle& cmpi; ble\cr + cmpibno& cmpijno& cmpi; bno\cr + cmpibne& cmpijne& cmpi; bne\cr + cmpibo& cmpijo& cmpi; bo\cr + cmpobe& cmpoje& cmpo; be\cr + cmpobg& cmpojg& cmpo; bg\cr + cmpobge& cmpojge& cmpo; bge\cr + cmpobl& cmpojl& cmpo; bl\cr + cmpoble& cmpojle& cmpo; ble\cr + cmpobne& cmpojne& cmpo; bne\cr} +@end tex +@c END TEXI2ROFF-KILL diff --git a/gas/doc/c-sparc.texi b/gas/doc/c-sparc.texi new file mode 100644 index 0000000..ae979a9 --- /dev/null +++ b/gas/doc/c-sparc.texi @@ -0,0 +1,122 @@ +@c Copyright (C) 1991, 1992, 1993, 1994, 1995 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 Sparc-Dependent +@chapter SPARC Dependent Features +@end ifset +@ifclear GENERIC +@node Machine Dependencies +@chapter SPARC Dependent Features +@end ifclear + +@cindex SPARC support +@menu +* Sparc-Opts:: Options +* Sparc-Float:: Floating Point +* Sparc-Directives:: Sparc Machine Directives +@end menu + +@node Sparc-Opts +@section Options + +@cindex options for SPARC +@cindex SPARC options +@cindex architectures, SPARC +@cindex SPARC architectures +The SPARC chip family includes several successive levels (or other +variants) of chip, using the same core instruction set, but including +a few additional instructions at each level. + +By default, @code{@value{AS}} assumes the core instruction set (SPARC +v6), but ``bumps'' the architecture level as needed: it switches to +successively higher architectures as it encounters instructions that +only exist in the higher levels. + +@table @code +@kindex -Av6 +@kindex Av7 +@kindex -Av8 +@kindex -Av9 +@kindex -Asparclite +@item -Av6 | -Av7 | -Av8 | -Av9 | -Asparclite +Use one of the @samp{-A} options to select one of the SPARC +architectures explicitly. If you select an architecture explicitly, +@code{@value{AS}} reports a fatal error if it encounters an instruction +or feature requiring a higher level. + +@item -bump +Permit the assembler to ``bump'' the architecture level as required, but +warn whenever it is necessary to switch to another level. +@end table + +@ignore +@c FIXME: (sparc) Fill in "syntax" section! +@c subsection syntax +I don't know anything about Sparc syntax. Someone who does +will have to write this section. +@end ignore + +@node Sparc-Float +@section Floating Point + +@cindex floating point, SPARC (@sc{ieee}) +@cindex SPARC floating point (@sc{ieee}) +The Sparc uses @sc{ieee} floating-point numbers. + +@node Sparc-Directives +@section Sparc Machine Directives + +@cindex SPARC machine directives +@cindex machine directives, SPARC +The Sparc version of @code{@value{AS}} supports the following additional +machine directives: + +@table @code +@cindex @code{align} directive, SPARC +@item .align +This must be followed by the desired alignment in bytes. + +@cindex @code{common} directive, SPARC +@item .common +This must be followed by a symbol name, a positive number, and +@code{"bss"}. This behaves somewhat like @code{.comm}, but the +syntax is different. + +@cindex @code{half} directive, SPARC +@item .half +This is functionally identical to @code{.short}. + +@cindex @code{proc} directive, SPARC +@item .proc +This directive is ignored. Any text following it on the same +line is also ignored. + +@cindex @code{reserve} directive, SPARC +@item .reserve +This must be followed by a symbol name, a positive number, and +@code{"bss"}. This behaves somewhat like @code{.lcomm}, but the +syntax is different. + +@cindex @code{seg} directive, SPARC +@item .seg +This must be followed by @code{"text"}, @code{"data"}, or +@code{"data1"}. It behaves like @code{.text}, @code{.data}, or +@code{.data 1}. + +@cindex @code{skip} directive, SPARC +@item .skip +This is functionally identical to the @code{.space} directive. + +@cindex @code{word} directive, SPARC +@item .word +On the Sparc, the @code{.word} directive produces 32 bit values, +instead of the 16 bit values it produces on many other machines. + +@cindex @code{xword} directive, SPARC +@item .xword +On the Sparc V9 processor, the @code{.xword} directive produces +64 bit values. +@end table + diff --git a/gas/doc/c-vax.texi b/gas/doc/c-vax.texi new file mode 100644 index 0000000..7b56604 --- /dev/null +++ b/gas/doc/c-vax.texi @@ -0,0 +1,323 @@ +@c Copyright (C) 1991, 1992, 1993, 1994, 1995 Free Software Foundation, Inc. +@c This is part of the GAS manual. +@c For copying conditions, see the file as.texinfo. +@ifset GENERIC +@node Vax-Dependent +@chapter VAX Dependent Features +@cindex VAX support + +@end ifset +@ifclear GENERIC +@node Machine Dependencies +@chapter VAX Dependent Features +@cindex VAX support + +@end ifclear + +@menu +* Vax-Opts:: VAX Command-Line Options +* VAX-float:: VAX Floating Point +* VAX-directives:: Vax Machine Directives +* VAX-opcodes:: VAX Opcodes +* VAX-branch:: VAX Branch Improvement +* VAX-operands:: VAX Operands +* VAX-no:: Not Supported on VAX +@end menu + + +@node Vax-Opts +@section VAX Command-Line Options + +@cindex command-line options ignored, VAX +@cindex VAX command-line options ignored +The Vax version of @code{@value{AS}} accepts any of the following options, +gives a warning message that the option was ignored and proceeds. +These options are for compatibility with scripts designed for other +people's assemblers. + +@table @code +@cindex @code{-D}, ignored on VAX +@cindex @code{-S}, ignored on VAX +@cindex @code{-T}, ignored on VAX +@item @code{-D} (Debug) +@itemx @code{-S} (Symbol Table) +@itemx @code{-T} (Token Trace) +These are obsolete options used to debug old assemblers. + +@cindex @code{-d}, VAX option +@item @code{-d} (Displacement size for JUMPs) +This option expects a number following the @samp{-d}. Like options +that expect filenames, the number may immediately follow the +@samp{-d} (old standard) or constitute the whole of the command line +argument that follows @samp{-d} (@sc{gnu} standard). + +@cindex @code{-V}, redundant on VAX +@item @code{-V} (Virtualize Interpass Temporary File) +Some other assemblers use a temporary file. This option +commanded them to keep the information in active memory rather +than in a disk file. @code{@value{AS}} always does this, so this +option is redundant. + +@cindex @code{-J}, ignored on VAX +@item @code{-J} (JUMPify Longer Branches) +Many 32-bit computers permit a variety of branch instructions +to do the same job. Some of these instructions are short (and +fast) but have a limited range; others are long (and slow) but +can branch anywhere in virtual memory. Often there are 3 +flavors of branch: short, medium and long. Some other +assemblers would emit short and medium branches, unless told by +this option to emit short and long branches. + +@cindex @code{-t}, ignored on VAX +@item @code{-t} (Temporary File Directory) +Some other assemblers may use a temporary file, and this option +takes a filename being the directory to site the temporary +file. Since @code{@value{AS}} does not use a temporary disk file, this +option makes no difference. @samp{-t} needs exactly one +filename. +@end table + +@cindex VMS (VAX) options +@cindex options for VAX/VMS +@cindex VAX/VMS options +@cindex @code{-h} option, VAX/VMS +@cindex @code{-+} option, VAX/VMS +@cindex Vax-11 C compatibility +@cindex symbols with lowercase, VAX/VMS +@c FIXME! look into "I think" below, correct if needed, delete. +The Vax version of the assembler accepts two options when +compiled for VMS. They are @samp{-h}, and @samp{-+}. The +@samp{-h} option prevents @code{@value{AS}} from modifying the +symbol-table entries for symbols that contain lowercase +characters (I think). The @samp{-+} option causes @code{@value{AS}} to +print warning messages if the FILENAME part of the object file, +or any symbol name is larger than 31 characters. The @samp{-+} +option also inserts some code following the @samp{_main} +symbol so that the object file is compatible with Vax-11 +"C". + +@node VAX-float +@section VAX Floating Point + +@cindex VAX floating point +@cindex floating point, VAX +Conversion of flonums to floating point is correct, and +compatible with previous assemblers. Rounding is +towards zero if the remainder is exactly half the least significant bit. + +@code{D}, @code{F}, @code{G} and @code{H} floating point formats +are understood. + +Immediate floating literals (@emph{e.g.} @samp{S`$6.9}) +are rendered correctly. Again, rounding is towards zero in the +boundary case. + +@cindex @code{float} directive, VAX +@cindex @code{double} directive, VAX +The @code{.float} directive produces @code{f} format numbers. +The @code{.double} directive produces @code{d} format numbers. + +@node VAX-directives +@section Vax Machine Directives + +@cindex machine directives, VAX +@cindex VAX machine directives +The Vax version of the assembler supports four directives for +generating Vax floating point constants. They are described in the +table below. + +@cindex wide floating point directives, VAX +@table @code +@cindex @code{dfloat} directive, VAX +@item .dfloat +This expects zero or more flonums, separated by commas, and +assembles Vax @code{d} format 64-bit floating point constants. + +@cindex @code{ffloat} directive, VAX +@item .ffloat +This expects zero or more flonums, separated by commas, and +assembles Vax @code{f} format 32-bit floating point constants. + +@cindex @code{gfloat} directive, VAX +@item .gfloat +This expects zero or more flonums, separated by commas, and +assembles Vax @code{g} format 64-bit floating point constants. + +@cindex @code{hfloat} directive, VAX +@item .hfloat +This expects zero or more flonums, separated by commas, and +assembles Vax @code{h} format 128-bit floating point constants. + +@end table + +@node VAX-opcodes +@section VAX Opcodes + +@cindex VAX opcode mnemonics +@cindex opcode mnemonics, VAX +@cindex mnemonics for opcodes, VAX +All DEC mnemonics are supported. Beware that @code{case@dots{}} +instructions have exactly 3 operands. The dispatch table that +follows the @code{case@dots{}} instruction should be made with +@code{.word} statements. This is compatible with all unix +assemblers we know of. + +@node VAX-branch +@section VAX Branch Improvement + +@cindex VAX branch improvement +@cindex branch improvement, VAX +@cindex pseudo-ops for branch, VAX +Certain pseudo opcodes are permitted. They are for branch +instructions. They expand to the shortest branch instruction that +reaches the target. Generally these mnemonics are made by +substituting @samp{j} for @samp{b} at the start of a DEC mnemonic. +This feature is included both for compatibility and to help +compilers. If you do not need this feature, avoid these +opcodes. Here are the mnemonics, and the code they can expand into. + +@table @code +@item jbsb +@samp{Jsb} is already an instruction mnemonic, so we chose @samp{jbsb}. +@table @asis +@item (byte displacement) +@kbd{bsbb @dots{}} +@item (word displacement) +@kbd{bsbw @dots{}} +@item (long displacement) +@kbd{jsb @dots{}} +@end table +@item jbr +@itemx jr +Unconditional branch. +@table @asis +@item (byte displacement) +@kbd{brb @dots{}} +@item (word displacement) +@kbd{brw @dots{}} +@item (long displacement) +@kbd{jmp @dots{}} +@end table +@item j@var{COND} +@var{COND} may be any one of the conditional branches +@code{neq}, @code{nequ}, @code{eql}, @code{eqlu}, @code{gtr}, +@code{geq}, @code{lss}, @code{gtru}, @code{lequ}, @code{vc}, @code{vs}, +@code{gequ}, @code{cc}, @code{lssu}, @code{cs}. +@var{COND} may also be one of the bit tests +@code{bs}, @code{bc}, @code{bss}, @code{bcs}, @code{bsc}, @code{bcc}, +@code{bssi}, @code{bcci}, @code{lbs}, @code{lbc}. +@var{NOTCOND} is the opposite condition to @var{COND}. +@table @asis +@item (byte displacement) +@kbd{b@var{COND} @dots{}} +@item (word displacement) +@kbd{b@var{NOTCOND} foo ; brw @dots{} ; foo:} +@item (long displacement) +@kbd{b@var{NOTCOND} foo ; jmp @dots{} ; foo:} +@end table +@item jacb@var{X} +@var{X} may be one of @code{b d f g h l w}. +@table @asis +@item (word displacement) +@kbd{@var{OPCODE} @dots{}} +@item (long displacement) +@example +@var{OPCODE} @dots{}, foo ; +brb bar ; +foo: jmp @dots{} ; +bar: +@end example +@end table +@item jaob@var{YYY} +@var{YYY} may be one of @code{lss leq}. +@item jsob@var{ZZZ} +@var{ZZZ} may be one of @code{geq gtr}. +@table @asis +@item (byte displacement) +@kbd{@var{OPCODE} @dots{}} +@item (word displacement) +@example +@var{OPCODE} @dots{}, foo ; +brb bar ; +foo: brw @var{destination} ; +bar: +@end example +@item (long displacement) +@example +@var{OPCODE} @dots{}, foo ; +brb bar ; +foo: jmp @var{destination} ; +bar: +@end example +@end table +@item aobleq +@itemx aoblss +@itemx sobgeq +@itemx sobgtr +@table @asis +@item (byte displacement) +@kbd{@var{OPCODE} @dots{}} +@item (word displacement) +@example +@var{OPCODE} @dots{}, foo ; +brb bar ; +foo: brw @var{destination} ; +bar: +@end example +@item (long displacement) +@example +@var{OPCODE} @dots{}, foo ; +brb bar ; +foo: jmp @var{destination} ; +bar: +@end example +@end table +@end table + +@node VAX-operands +@section VAX Operands + +@cindex VAX operand notation +@cindex operand notation, VAX +@cindex immediate character, VAX +@cindex VAX immediate character +The immediate character is @samp{$} for Unix compatibility, not +@samp{#} as DEC writes it. + +@cindex indirect character, VAX +@cindex VAX indirect character +The indirect character is @samp{*} for Unix compatibility, not +@samp{@@} as DEC writes it. + +@cindex displacement sizing character, VAX +@cindex VAX displacement sizing character +The displacement sizing character is @samp{`} (an accent grave) for +Unix compatibility, not @samp{^} as DEC writes it. The letter +preceding @samp{`} may have either case. @samp{G} is not +understood, but all other letters (@code{b i l s w}) are understood. + +@cindex register names, VAX +@cindex VAX register names +Register names understood are @code{r0 r1 r2 @dots{} r15 ap fp sp +pc}. Upper and lower case letters are equivalent. + +For instance +@smallexample +tstb *w`$4(r5) +@end smallexample + +Any expression is permitted in an operand. Operands are comma +separated. + +@c There is some bug to do with recognizing expressions +@c in operands, but I forget what it is. It is +@c a syntax clash because () is used as an address mode +@c and to encapsulate sub-expressions. + +@node VAX-no +@section Not Supported on VAX + +@cindex VAX bitfields not supported +@cindex bitfields, not supported on VAX +Vax bit fields can not be assembled with @code{@value{AS}}. Someone +can add the required code if they really need it. diff --git a/gas/doc/gasp.texi b/gas/doc/gasp.texi index 32ab63d..64cd6f4 100644 --- a/gas/doc/gasp.texi +++ b/gas/doc/gasp.texi @@ -37,7 +37,7 @@ END-INFO-DIR-ENTRY @end tex @vskip 0pt plus 1filll -Copyright @copyright{} 1994 Free Software Foundation, Inc. +Copyright @copyright{} 1994, 1995 Free Software Foundation, Inc. Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice @@ -53,7 +53,7 @@ into another language, under the above conditions for modified versions. @end titlepage @ifinfo -Copyright @copyright{} 1994 Free Software Foundation, Inc. +Copyright @copyright{} 1994, 1995 Free Software Foundation, Inc. Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice |