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diff --git a/binutils-2.17/gas/doc/c-vax.texi b/binutils-2.17/gas/doc/c-vax.texi deleted file mode 100644 index ac9a4ea7..00000000 --- a/binutils-2.17/gas/doc/c-vax.texi +++ /dev/null @@ -1,358 +0,0 @@ -@c Copyright 1991, 1992, 1993, 1994, 1995, 1996, 1998, 2002 -@c Free Software Foundation, Inc. -@c This is part of the GAS manual. -@c For copying conditions, see the file as.texinfo. -@c VAX/VMS description enhanced and corrected by Klaus K"aempf, kkaempf@progis.de -@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 Vax-11 C compatibility -@cindex symbols with uppercase, VAX/VMS -The Vax version of the assembler accepts additional options when -compiled for VMS: - -@table @samp -@cindex @samp{-h} option, VAX/VMS -@item -h @var{n} -External symbol or section (used for global variables) names are not -case sensitive on VAX/VMS and always mapped to upper case. This is -contrary to the C language definition which explicitly distinguishes -upper and lower case. To implement a standard conforming C compiler, -names must be changed (mapped) to preserve the case information. The -default mapping is to convert all lower case characters to uppercase and -adding an underscore followed by a 6 digit hex value, representing a 24 -digit binary value. The one digits in the binary value represent which -characters are uppercase in the original symbol name. - -The @samp{-h @var{n}} option determines how we map names. This takes -several values. No @samp{-h} switch at all allows case hacking as -described above. A value of zero (@samp{-h0}) implies names should be -upper case, and inhibits the case hack. A value of 2 (@samp{-h2}) -implies names should be all lower case, with no case hack. A value of 3 -(@samp{-h3}) implies that case should be preserved. The value 1 is -unused. The @code{-H} option directs @code{@value{AS}} to display -every mapped symbol during assembly. - -Symbols whose names include a dollar sign @samp{$} are exceptions to the -general name mapping. These symbols are normally only used to reference -VMS library names. Such symbols are always mapped to upper case. - -@cindex @samp{-+} option, VAX/VMS -@item -+ -The @samp{-+} option causes @code{@value{AS}} to truncate any symbol -name larger than 31 characters. The @samp{-+} option also prevents some -code following the @samp{_main} symbol normally added to make the object -file compatible with Vax-11 "C". - -@cindex @samp{-1} option, VAX/VMS -@item -1 -This option is ignored for backward compatibility with @code{@value{AS}} -version 1.x. - -@cindex @samp{-H} option, VAX/VMS -@item -H -The @samp{-H} option causes @code{@value{AS}} to print every symbol -which was changed by case mapping. -@end table - -@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. |