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diff --git a/binutils-2.24/gas/doc/c-i960.texi b/binutils-2.24/gas/doc/c-i960.texi deleted file mode 100644 index e8a2e61f..00000000 --- a/binutils-2.24/gas/doc/c-i960.texi +++ /dev/null @@ -1,325 +0,0 @@ -@c Copyright 1991, 1992, 1993, 1994, 1995, 1996, 2002, 2006, 2011 -@c 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 -* Syntax of i960:: i960 Syntax -@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 difference 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 labeled @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, i960 -@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 - -@node Syntax of i960 -@section Syntax for the i960 -@menu -* i960-Chars:: Special Characters -@end menu - -@node i960-Chars -@subsection Special Characters - -@cindex line comment character, i960 -@cindex i960 line comment character -The presence of a @samp{#} on a line indicates the start of a comment -that extends to the end of the current line. - -If a @samp{#} appears as the first character of a line, 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, i960 -@cindex statement separator, i960 -@cindex i960 line separator -The @samp{;} character can be used to separate statements on the same -line. |