905 lines
28 KiB
Text
905 lines
28 KiB
Text
@c Copyright (C) 1991-2016 Free Software Foundation, Inc.
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@c This is part of the GAS manual.
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@c For copying conditions, see the file as.texinfo.
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@ifset GENERIC
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@page
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@node Sparc-Dependent
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@chapter SPARC Dependent Features
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@end ifset
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@ifclear GENERIC
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@node Machine Dependencies
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@chapter SPARC Dependent Features
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@end ifclear
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@cindex SPARC support
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@menu
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* Sparc-Opts:: Options
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* Sparc-Aligned-Data:: Option to enforce aligned data
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* Sparc-Syntax:: Syntax
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* Sparc-Float:: Floating Point
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* Sparc-Directives:: Sparc Machine Directives
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@end menu
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@node Sparc-Opts
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@section Options
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@cindex options for SPARC
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@cindex SPARC options
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@cindex architectures, SPARC
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@cindex SPARC architectures
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The SPARC chip family includes several successive versions, using the same
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core instruction set, but including a few additional instructions at
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each version. There are exceptions to this however. For details on what
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instructions each variant supports, please see the chip's architecture
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reference manual.
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By default, @code{@value{AS}} assumes the core instruction set (SPARC
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v6), but ``bumps'' the architecture level as needed: it switches to
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successively higher architectures as it encounters instructions that
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only exist in the higher levels.
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If not configured for SPARC v9 (@code{sparc64-*-*}) GAS will not bump
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past sparclite by default, an option must be passed to enable the
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v9 instructions.
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GAS treats sparclite as being compatible with v8, unless an architecture
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is explicitly requested. SPARC v9 is always incompatible with sparclite.
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@c The order here is the same as the order of enum sparc_opcode_arch_val
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@c to give the user a sense of the order of the "bumping".
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@table @code
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@kindex -Av6
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@kindex -Av7
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@kindex -Av8
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@kindex -Aleon
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@kindex -Asparclet
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@kindex -Asparclite
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@kindex -Av9
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@kindex -Av9a
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@kindex -Av9b
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@kindex -Av9c
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@kindex -Av9d
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@kindex -Av9e
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@kindex -Av9v
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@kindex -Av9m
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@kindex -Asparc
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@kindex -Asparcvis
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@kindex -Asparcvis2
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@kindex -Asparcfmaf
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@kindex -Asparcima
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@kindex -Asparcvis3
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@kindex -Asparcvis3r
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@item -Av6 | -Av7 | -Av8 | -Aleon | -Asparclet | -Asparclite
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@itemx -Av8plus | -Av8plusa | -Av8plusb | -Av8plusc | -Av8plusd | -Av8plusv
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@itemx -Av9 | -Av9a | -Av9b | -Av9c | -Av9d | -Av9e | -Av9v | -Av9m
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@itemx -Asparc | -Asparcvis | -Asparcvis2 | -Asparcfmaf | -Asparcima
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@itemx -Asparcvis3 | -Asparcvis3r
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Use one of the @samp{-A} options to select one of the SPARC
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architectures explicitly. If you select an architecture explicitly,
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@code{@value{AS}} reports a fatal error if it encounters an instruction
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or feature requiring an incompatible or higher level.
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@samp{-Av8plus}, @samp{-Av8plusa}, @samp{-Av8plusb}, @samp{-Av8plusc},
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@samp{-Av8plusd}, and @samp{-Av8plusv} select a 32 bit environment.
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@samp{-Av9}, @samp{-Av9a}, @samp{-Av9b}, @samp{-Av9c}, @samp{-Av9d},
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@samp{-Av9e}, @samp{-Av9v} and @samp{-Av9m} select a 64 bit
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environment and are not available unless GAS is explicitly configured
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with 64 bit environment support.
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@samp{-Av8plusa} and @samp{-Av9a} enable the SPARC V9 instruction set with
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UltraSPARC VIS 1.0 extensions.
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@samp{-Av8plusb} and @samp{-Av9b} enable the UltraSPARC VIS 2.0 instructions,
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as well as the instructions enabled by @samp{-Av8plusa} and @samp{-Av9a}.
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@samp{-Av8plusc} and @samp{-Av9c} enable the UltraSPARC Niagara instructions,
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as well as the instructions enabled by @samp{-Av8plusb} and @samp{-Av9b}.
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@samp{-Av8plusd} and @samp{-Av9d} enable the floating point fused
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multiply-add, VIS 3.0, and HPC extension instructions, as well as the
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instructions enabled by @samp{-Av8plusc} and @samp{-Av9c}.
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@samp{-Av8pluse} and @samp{-Av9e} enable the cryptographic
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instructions, as well as the instructions enabled by @samp{-Av8plusd}
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and @samp{-Av9d}.
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@samp{-Av8plusv} and @samp{-Av9v} enable floating point unfused
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multiply-add, and integer multiply-add, as well as the instructions
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enabled by @samp{-Av8pluse} and @samp{-Av9e}.
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@samp{-Av8plusm} and @samp{-Av9m} enable the VIS 4.0, subtract extended,
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xmpmul, xmontmul and xmontsqr instructions, as well as the instructions
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enabled by @samp{-Av8plusv} and @samp{-Av9v}.
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@samp{-Asparc} specifies a v9 environment. It is equivalent to
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@samp{-Av9} if the word size is 64-bit, and @samp{-Av8plus} otherwise.
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@samp{-Asparcvis} specifies a v9a environment. It is equivalent to
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@samp{-Av9a} if the word size is 64-bit, and @samp{-Av8plusa} otherwise.
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@samp{-Asparcvis2} specifies a v9b environment. It is equivalent to
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@samp{-Av9b} if the word size is 64-bit, and @samp{-Av8plusb} otherwise.
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@samp{-Asparcfmaf} specifies a v9b environment with the floating point
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fused multiply-add instructions enabled.
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@samp{-Asparcima} specifies a v9b environment with the integer
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multiply-add instructions enabled.
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@samp{-Asparcvis3} specifies a v9b environment with the VIS 3.0,
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HPC , and floating point fused multiply-add instructions enabled.
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@samp{-Asparcvis3r} specifies a v9b environment with the VIS 3.0, HPC,
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and floating point unfused multiply-add instructions enabled.
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@samp{-Asparc5} is equivalent to @samp{-Av9m}.
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@item -xarch=v8plus | -xarch=v8plusa | -xarch=v8plusb | -xarch=v8plusc
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@itemx -xarch=v8plusd | -xarch=v8plusv | -xarch=v9 | -xarch=v9a
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@itemx -xarch=v9b | -xarch=v9c | -xarch=v9d | -xarch=v9e | -xarch=v9v | -xarch=v9m
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@itemx -xarch=sparc | -xarch=sparcvis | -xarch=sparcvis2
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@itemx -xarch=sparcfmaf | -xarch=sparcima | -xarch=sparcvis3
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@itemx -xarch=sparcvis3r | -xarch=sparc5
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For compatibility with the SunOS v9 assembler. These options are
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equivalent to -Av8plus, -Av8plusa, -Av8plusb, -Av8plusc, -Av8plusd,
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-Av8plusv, -Av9, -Av9a, -Av9b, -Av9c, -Av9d, -Av9e, -Av9v, -Av9m,
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-Asparc, -Asparcvis, -Asparcvis2, -Asparcfmaf, -Asparcima,
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-Asparcvis3, and -Asparcvis3r, respectively.
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@item -bump
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Warn whenever it is necessary to switch to another level.
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If an architecture level is explicitly requested, GAS will not issue
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warnings until that level is reached, and will then bump the level
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as required (except between incompatible levels).
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@item -32 | -64
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Select the word size, either 32 bits or 64 bits.
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These options are only available with the ELF object file format,
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and require that the necessary BFD support has been included.
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@end table
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@node Sparc-Aligned-Data
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@section Enforcing aligned data
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@cindex data alignment on SPARC
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@cindex SPARC data alignment
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SPARC GAS normally permits data to be misaligned. For example, it
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permits the @code{.long} pseudo-op to be used on a byte boundary.
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However, the native SunOS assemblers issue an error when they see
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misaligned data.
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@kindex --enforce-aligned-data
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You can use the @code{--enforce-aligned-data} option to make SPARC GAS
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also issue an error about misaligned data, just as the SunOS
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assemblers do.
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The @code{--enforce-aligned-data} option is not the default because gcc
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issues misaligned data pseudo-ops when it initializes certain packed
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data structures (structures defined using the @code{packed} attribute).
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You may have to assemble with GAS in order to initialize packed data
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structures in your own code.
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@cindex SPARC syntax
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@cindex syntax, SPARC
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@node Sparc-Syntax
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@section Sparc Syntax
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The assembler syntax closely follows The Sparc Architecture Manual,
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versions 8 and 9, as well as most extensions defined by Sun
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for their UltraSPARC and Niagara line of processors.
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@menu
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* Sparc-Chars:: Special Characters
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* Sparc-Regs:: Register Names
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* Sparc-Constants:: Constant Names
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* Sparc-Relocs:: Relocations
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* Sparc-Size-Translations:: Size Translations
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@end menu
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@node Sparc-Chars
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@subsection Special Characters
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@cindex line comment character, Sparc
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@cindex Sparc line comment character
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A @samp{!} character appearing anywhere on a line indicates the start
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of a comment that extends to the end of that line.
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If a @samp{#} appears as the first character of a line then the whole
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line is treated as a comment, but in this case the line could also be
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a logical line number directive (@pxref{Comments}) or a preprocessor
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control command (@pxref{Preprocessing}).
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@cindex line separator, Sparc
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@cindex statement separator, Sparc
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@cindex Sparc line separator
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@samp{;} can be used instead of a newline to separate statements.
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@node Sparc-Regs
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@subsection Register Names
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@cindex Sparc registers
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@cindex register names, Sparc
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The Sparc integer register file is broken down into global,
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outgoing, local, and incoming.
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@itemize @bullet
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@item
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The 8 global registers are referred to as @samp{%g@var{n}}.
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@item
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The 8 outgoing registers are referred to as @samp{%o@var{n}}.
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@item
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The 8 local registers are referred to as @samp{%l@var{n}}.
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@item
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The 8 incoming registers are referred to as @samp{%i@var{n}}.
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@item
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The frame pointer register @samp{%i6} can be referenced using
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the alias @samp{%fp}.
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@item
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The stack pointer register @samp{%o6} can be referenced using
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the alias @samp{%sp}.
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@end itemize
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Floating point registers are simply referred to as @samp{%f@var{n}}.
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When assembling for pre-V9, only 32 floating point registers
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are available. For V9 and later there are 64, but there are
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restrictions when referencing the upper 32 registers. They
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can only be accessed as double or quad, and thus only even
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or quad numbered accesses are allowed. For example, @samp{%f34}
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is a legal floating point register, but @samp{%f35} is not.
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Floating point registers accessed as double can also be referred using
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the @samp{%d@var{n}} notation, where @var{n} is even. Similarly,
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floating point registers accessed as quad can be referred using the
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@samp{%q@var{n}} notation, where @var{n} is a multiple of 4. For
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example, @samp{%f4} can be denoted as both @samp{%d4} and @samp{%q4}.
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On the other hand, @samp{%f2} can be denoted as @samp{%d2} but not as
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@samp{%q2}.
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Certain V9 instructions allow access to ancillary state registers.
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Most simply they can be referred to as @samp{%asr@var{n}} where
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@var{n} can be from 16 to 31. However, there are some aliases
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defined to reference ASR registers defined for various UltraSPARC
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processors:
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@itemize @bullet
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@item
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The tick compare register is referred to as @samp{%tick_cmpr}.
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@item
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The system tick register is referred to as @samp{%stick}. An alias,
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@samp{%sys_tick}, exists but is deprecated and should not be used
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by new software.
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@item
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The system tick compare register is referred to as @samp{%stick_cmpr}.
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An alias, @samp{%sys_tick_cmpr}, exists but is deprecated and should
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not be used by new software.
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@item
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The software interrupt register is referred to as @samp{%softint}.
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@item
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The set software interrupt register is referred to as @samp{%set_softint}.
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The mnemonic @samp{%softint_set} is provided as an alias.
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@item
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The clear software interrupt register is referred to as
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@samp{%clear_softint}. The mnemonic @samp{%softint_clear} is provided
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as an alias.
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@item
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The performance instrumentation counters register is referred to as
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@samp{%pic}.
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@item
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The performance control register is referred to as @samp{%pcr}.
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@item
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The graphics status register is referred to as @samp{%gsr}.
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@item
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The V9 dispatch control register is referred to as @samp{%dcr}.
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@end itemize
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Various V9 branch and conditional move instructions allow
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specification of which set of integer condition codes to
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test. These are referred to as @samp{%xcc} and @samp{%icc}.
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Additionally, GAS supports the so-called ``natural'' condition codes;
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these are referred to as @samp{%ncc} and reference to @samp{%icc} if
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the word size is 32, @samp{%xcc} if the word size is 64.
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In V9, there are 4 sets of floating point condition codes
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which are referred to as @samp{%fcc@var{n}}.
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Several special privileged and non-privileged registers
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exist:
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@itemize @bullet
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@item
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The V9 address space identifier register is referred to as @samp{%asi}.
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@item
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The V9 restorable windows register is referred to as @samp{%canrestore}.
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@item
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The V9 savable windows register is referred to as @samp{%cansave}.
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@item
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The V9 clean windows register is referred to as @samp{%cleanwin}.
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@item
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The V9 current window pointer register is referred to as @samp{%cwp}.
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@item
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The floating-point queue register is referred to as @samp{%fq}.
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@item
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The V8 co-processor queue register is referred to as @samp{%cq}.
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@item
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The floating point status register is referred to as @samp{%fsr}.
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@item
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The other windows register is referred to as @samp{%otherwin}.
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@item
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The V9 program counter register is referred to as @samp{%pc}.
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@item
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The V9 next program counter register is referred to as @samp{%npc}.
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@item
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The V9 processor interrupt level register is referred to as @samp{%pil}.
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@item
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The V9 processor state register is referred to as @samp{%pstate}.
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@item
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The trap base address register is referred to as @samp{%tba}.
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@item
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The V9 tick register is referred to as @samp{%tick}.
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@item
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The V9 trap level is referred to as @samp{%tl}.
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@item
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The V9 trap program counter is referred to as @samp{%tpc}.
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@item
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The V9 trap next program counter is referred to as @samp{%tnpc}.
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@item
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The V9 trap state is referred to as @samp{%tstate}.
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@item
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The V9 trap type is referred to as @samp{%tt}.
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@item
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The V9 condition codes is referred to as @samp{%ccr}.
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@item
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The V9 floating-point registers state is referred to as @samp{%fprs}.
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@item
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The V9 version register is referred to as @samp{%ver}.
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@item
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The V9 window state register is referred to as @samp{%wstate}.
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@item
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The Y register is referred to as @samp{%y}.
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@item
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The V8 window invalid mask register is referred to as @samp{%wim}.
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@item
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The V8 processor state register is referred to as @samp{%psr}.
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@item
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The V9 global register level register is referred to as @samp{%gl}.
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@end itemize
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Several special register names exist for hypervisor mode code:
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@itemize @bullet
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@item
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The hyperprivileged processor state register is referred to as
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@samp{%hpstate}.
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@item
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The hyperprivileged trap state register is referred to as @samp{%htstate}.
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@item
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The hyperprivileged interrupt pending register is referred to as
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@samp{%hintp}.
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@item
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The hyperprivileged trap base address register is referred to as
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@samp{%htba}.
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@item
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The hyperprivileged implementation version register is referred
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to as @samp{%hver}.
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@item
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The hyperprivileged system tick offset register is referred to as
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@samp{%hstick_offset}. Note that there is no @samp{%hstick} register,
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the normal @samp{%stick} is used.
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@item
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The hyperprivileged system tick enable register is referred to as
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@samp{%hstick_enable}.
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@item
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The hyperprivileged system tick compare register is referred
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to as @samp{%hstick_cmpr}.
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@end itemize
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@node Sparc-Constants
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@subsection Constants
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@cindex Sparc constants
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@cindex constants, Sparc
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Several Sparc instructions take an immediate operand field for
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which mnemonic names exist. Two such examples are @samp{membar}
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and @samp{prefetch}. Another example are the set of V9
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memory access instruction that allow specification of an
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address space identifier.
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The @samp{membar} instruction specifies a memory barrier that is
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the defined by the operand which is a bitmask. The supported
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mask mnemonics are:
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@itemize @bullet
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@item
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@samp{#Sync} requests that all operations (including nonmemory
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reference operations) appearing prior to the @code{membar} must have
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been performed and the effects of any exceptions become visible before
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any instructions after the @code{membar} may be initiated. This
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corresponds to @code{membar} cmask field bit 2.
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@item
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@samp{#MemIssue} requests that all memory reference operations
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appearing prior to the @code{membar} must have been performed before
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any memory operation after the @code{membar} may be initiated. This
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corresponds to @code{membar} cmask field bit 1.
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@item
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@samp{#Lookaside} requests that a store appearing prior to the
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@code{membar} must complete before any load following the
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@code{membar} referencing the same address can be initiated. This
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corresponds to @code{membar} cmask field bit 0.
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@item
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@samp{#StoreStore} defines that the effects of all stores appearing
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prior to the @code{membar} instruction must be visible to all
|
|
processors before the effect of any stores following the
|
|
@code{membar}. Equivalent to the deprecated @code{stbar} instruction.
|
|
This corresponds to @code{membar} mmask field bit 3.
|
|
|
|
@item
|
|
@samp{#LoadStore} defines all loads appearing prior to the
|
|
@code{membar} instruction must have been performed before the effect
|
|
of any stores following the @code{membar} is visible to any other
|
|
processor. This corresponds to @code{membar} mmask field bit 2.
|
|
|
|
@item
|
|
@samp{#StoreLoad} defines that the effects of all stores appearing
|
|
prior to the @code{membar} instruction must be visible to all
|
|
processors before loads following the @code{membar} may be performed.
|
|
This corresponds to @code{membar} mmask field bit 1.
|
|
|
|
@item
|
|
@samp{#LoadLoad} defines that all loads appearing prior to the
|
|
@code{membar} instruction must have been performed before any loads
|
|
following the @code{membar} may be performed. This corresponds to
|
|
@code{membar} mmask field bit 0.
|
|
|
|
@end itemize
|
|
|
|
These values can be ored together, for example:
|
|
|
|
@example
|
|
membar #Sync
|
|
membar #StoreLoad | #LoadLoad
|
|
membar #StoreLoad | #StoreStore
|
|
@end example
|
|
|
|
The @code{prefetch} and @code{prefetcha} instructions take a prefetch
|
|
function code. The following prefetch function code constant
|
|
mnemonics are available:
|
|
|
|
@itemize @bullet
|
|
@item
|
|
@samp{#n_reads} requests a prefetch for several reads, and corresponds
|
|
to a prefetch function code of 0.
|
|
|
|
@samp{#one_read} requests a prefetch for one read, and corresponds
|
|
to a prefetch function code of 1.
|
|
|
|
@samp{#n_writes} requests a prefetch for several writes (and possibly
|
|
reads), and corresponds to a prefetch function code of 2.
|
|
|
|
@samp{#one_write} requests a prefetch for one write, and corresponds
|
|
to a prefetch function code of 3.
|
|
|
|
@samp{#page} requests a prefetch page, and corresponds to a prefetch
|
|
function code of 4.
|
|
|
|
@samp{#invalidate} requests a prefetch invalidate, and corresponds to
|
|
a prefetch function code of 16.
|
|
|
|
@samp{#unified} requests a prefetch to the nearest unified cache, and
|
|
corresponds to a prefetch function code of 17.
|
|
|
|
@samp{#n_reads_strong} requests a strong prefetch for several reads,
|
|
and corresponds to a prefetch function code of 20.
|
|
|
|
@samp{#one_read_strong} requests a strong prefetch for one read,
|
|
and corresponds to a prefetch function code of 21.
|
|
|
|
@samp{#n_writes_strong} requests a strong prefetch for several writes,
|
|
and corresponds to a prefetch function code of 22.
|
|
|
|
@samp{#one_write_strong} requests a strong prefetch for one write,
|
|
and corresponds to a prefetch function code of 23.
|
|
|
|
Onle one prefetch code may be specified. Here are some examples:
|
|
|
|
@example
|
|
prefetch [%l0 + %l2], #one_read
|
|
prefetch [%g2 + 8], #n_writes
|
|
prefetcha [%g1] 0x8, #unified
|
|
prefetcha [%o0 + 0x10] %asi, #n_reads
|
|
@end example
|
|
|
|
The actual behavior of a given prefetch function code is processor
|
|
specific. If a processor does not implement a given prefetch
|
|
function code, it will treat the prefetch instruction as a nop.
|
|
|
|
For instructions that accept an immediate address space identifier,
|
|
@code{@value{AS}} provides many mnemonics corresponding to
|
|
V9 defined as well as UltraSPARC and Niagara extended values.
|
|
For example, @samp{#ASI_P} and @samp{#ASI_BLK_INIT_QUAD_LDD_AIUS}.
|
|
See the V9 and processor specific manuals for details.
|
|
|
|
@end itemize
|
|
|
|
@node Sparc-Relocs
|
|
@subsection Relocations
|
|
@cindex Sparc relocations
|
|
@cindex relocations, Sparc
|
|
|
|
ELF relocations are available as defined in the 32-bit and 64-bit
|
|
Sparc ELF specifications.
|
|
|
|
@code{R_SPARC_HI22} is obtained using @samp{%hi} and @code{R_SPARC_LO10}
|
|
is obtained using @samp{%lo}. Likewise @code{R_SPARC_HIX22} is
|
|
obtained from @samp{%hix} and @code{R_SPARC_LOX10} is obtained
|
|
using @samp{%lox}. For example:
|
|
|
|
@example
|
|
sethi %hi(symbol), %g1
|
|
or %g1, %lo(symbol), %g1
|
|
|
|
sethi %hix(symbol), %g1
|
|
xor %g1, %lox(symbol), %g1
|
|
@end example
|
|
|
|
These ``high'' mnemonics extract bits 31:10 of their operand,
|
|
and the ``low'' mnemonics extract bits 9:0 of their operand.
|
|
|
|
V9 code model relocations can be requested as follows:
|
|
|
|
@itemize @bullet
|
|
@item
|
|
@code{R_SPARC_HH22} is requested using @samp{%hh}. It can
|
|
also be generated using @samp{%uhi}.
|
|
@item
|
|
@code{R_SPARC_HM10} is requested using @samp{%hm}. It can
|
|
also be generated using @samp{%ulo}.
|
|
@item
|
|
@code{R_SPARC_LM22} is requested using @samp{%lm}.
|
|
|
|
@item
|
|
@code{R_SPARC_H44} is requested using @samp{%h44}.
|
|
@item
|
|
@code{R_SPARC_M44} is requested using @samp{%m44}.
|
|
@item
|
|
@code{R_SPARC_L44} is requested using @samp{%l44} or @samp{%l34}.
|
|
@item
|
|
@code{R_SPARC_H34} is requested using @samp{%h34}.
|
|
@end itemize
|
|
|
|
The @samp{%l34} generates a @code{R_SPARC_L44} relocation because it
|
|
calculates the necessary value, and therefore no explicit
|
|
@code{R_SPARC_L34} relocation needed to be created for this purpose.
|
|
|
|
The @samp{%h34} and @samp{%l34} relocations are used for the abs34 code
|
|
model. Here is an example abs34 address generation sequence:
|
|
|
|
@example
|
|
sethi %h34(symbol), %g1
|
|
sllx %g1, 2, %g1
|
|
or %g1, %l34(symbol), %g1
|
|
@end example
|
|
|
|
The PC relative relocation @code{R_SPARC_PC22} can be obtained by
|
|
enclosing an operand inside of @samp{%pc22}. Likewise, the
|
|
@code{R_SPARC_PC10} relocation can be obtained using @samp{%pc10}.
|
|
These are mostly used when assembling PIC code. For example, the
|
|
standard PIC sequence on Sparc to get the base of the global offset
|
|
table, PC relative, into a register, can be performed as:
|
|
|
|
@example
|
|
sethi %pc22(_GLOBAL_OFFSET_TABLE_-4), %l7
|
|
add %l7, %pc10(_GLOBAL_OFFSET_TABLE_+4), %l7
|
|
@end example
|
|
|
|
Several relocations exist to allow the link editor to potentially
|
|
optimize GOT data references. The @code{R_SPARC_GOTDATA_OP_HIX22}
|
|
relocation can obtained by enclosing an operand inside of
|
|
@samp{%gdop_hix22}. The @code{R_SPARC_GOTDATA_OP_LOX10}
|
|
relocation can obtained by enclosing an operand inside of
|
|
@samp{%gdop_lox10}. Likewise, @code{R_SPARC_GOTDATA_OP} can be
|
|
obtained by enclosing an operand inside of @samp{%gdop}.
|
|
For example, assuming the GOT base is in register @code{%l7}:
|
|
|
|
@example
|
|
sethi %gdop_hix22(symbol), %l1
|
|
xor %l1, %gdop_lox10(symbol), %l1
|
|
ld [%l7 + %l1], %l2, %gdop(symbol)
|
|
@end example
|
|
|
|
There are many relocations that can be requested for access to
|
|
thread local storage variables. All of the Sparc TLS mnemonics
|
|
are supported:
|
|
|
|
@itemize @bullet
|
|
@item
|
|
@code{R_SPARC_TLS_GD_HI22} is requested using @samp{%tgd_hi22}.
|
|
@item
|
|
@code{R_SPARC_TLS_GD_LO10} is requested using @samp{%tgd_lo10}.
|
|
@item
|
|
@code{R_SPARC_TLS_GD_ADD} is requested using @samp{%tgd_add}.
|
|
@item
|
|
@code{R_SPARC_TLS_GD_CALL} is requested using @samp{%tgd_call}.
|
|
|
|
@item
|
|
@code{R_SPARC_TLS_LDM_HI22} is requested using @samp{%tldm_hi22}.
|
|
@item
|
|
@code{R_SPARC_TLS_LDM_LO10} is requested using @samp{%tldm_lo10}.
|
|
@item
|
|
@code{R_SPARC_TLS_LDM_ADD} is requested using @samp{%tldm_add}.
|
|
@item
|
|
@code{R_SPARC_TLS_LDM_CALL} is requested using @samp{%tldm_call}.
|
|
|
|
@item
|
|
@code{R_SPARC_TLS_LDO_HIX22} is requested using @samp{%tldo_hix22}.
|
|
@item
|
|
@code{R_SPARC_TLS_LDO_LOX10} is requested using @samp{%tldo_lox10}.
|
|
@item
|
|
@code{R_SPARC_TLS_LDO_ADD} is requested using @samp{%tldo_add}.
|
|
|
|
@item
|
|
@code{R_SPARC_TLS_IE_HI22} is requested using @samp{%tie_hi22}.
|
|
@item
|
|
@code{R_SPARC_TLS_IE_LO10} is requested using @samp{%tie_lo10}.
|
|
@item
|
|
@code{R_SPARC_TLS_IE_LD} is requested using @samp{%tie_ld}.
|
|
@item
|
|
@code{R_SPARC_TLS_IE_LDX} is requested using @samp{%tie_ldx}.
|
|
@item
|
|
@code{R_SPARC_TLS_IE_ADD} is requested using @samp{%tie_add}.
|
|
|
|
@item
|
|
@code{R_SPARC_TLS_LE_HIX22} is requested using @samp{%tle_hix22}.
|
|
@item
|
|
@code{R_SPARC_TLS_LE_LOX10} is requested using @samp{%tle_lox10}.
|
|
@end itemize
|
|
|
|
Here are some example TLS model sequences.
|
|
|
|
First, General Dynamic:
|
|
|
|
@example
|
|
sethi %tgd_hi22(symbol), %l1
|
|
add %l1, %tgd_lo10(symbol), %l1
|
|
add %l7, %l1, %o0, %tgd_add(symbol)
|
|
call __tls_get_addr, %tgd_call(symbol)
|
|
nop
|
|
@end example
|
|
|
|
Local Dynamic:
|
|
|
|
@example
|
|
sethi %tldm_hi22(symbol), %l1
|
|
add %l1, %tldm_lo10(symbol), %l1
|
|
add %l7, %l1, %o0, %tldm_add(symbol)
|
|
call __tls_get_addr, %tldm_call(symbol)
|
|
nop
|
|
|
|
sethi %tldo_hix22(symbol), %l1
|
|
xor %l1, %tldo_lox10(symbol), %l1
|
|
add %o0, %l1, %l1, %tldo_add(symbol)
|
|
@end example
|
|
|
|
Initial Exec:
|
|
|
|
@example
|
|
sethi %tie_hi22(symbol), %l1
|
|
add %l1, %tie_lo10(symbol), %l1
|
|
ld [%l7 + %l1], %o0, %tie_ld(symbol)
|
|
add %g7, %o0, %o0, %tie_add(symbol)
|
|
|
|
sethi %tie_hi22(symbol), %l1
|
|
add %l1, %tie_lo10(symbol), %l1
|
|
ldx [%l7 + %l1], %o0, %tie_ldx(symbol)
|
|
add %g7, %o0, %o0, %tie_add(symbol)
|
|
@end example
|
|
|
|
And finally, Local Exec:
|
|
|
|
@example
|
|
sethi %tle_hix22(symbol), %l1
|
|
add %l1, %tle_lox10(symbol), %l1
|
|
add %g7, %l1, %l1
|
|
@end example
|
|
|
|
When assembling for 64-bit, and a secondary constant addend is
|
|
specified in an address expression that would normally generate
|
|
an @code{R_SPARC_LO10} relocation, the assembler will emit an
|
|
@code{R_SPARC_OLO10} instead.
|
|
|
|
@node Sparc-Size-Translations
|
|
@subsection Size Translations
|
|
@cindex Sparc size translations
|
|
@cindex size, translations, Sparc
|
|
|
|
Often it is desirable to write code in an operand size agnostic
|
|
manner. @code{@value{AS}} provides support for this via
|
|
operand size opcode translations. Translations are supported
|
|
for loads, stores, shifts, compare-and-swap atomics, and the
|
|
@samp{clr} synthetic instruction.
|
|
|
|
If generating 32-bit code, @code{@value{AS}} will generate the
|
|
32-bit opcode. Whereas if 64-bit code is being generated,
|
|
the 64-bit opcode will be emitted. For example @code{ldn}
|
|
will be transformed into @code{ld} for 32-bit code and
|
|
@code{ldx} for 64-bit code.
|
|
|
|
Here is an example meant to demonstrate all the supported
|
|
opcode translations:
|
|
|
|
@example
|
|
ldn [%o0], %o1
|
|
ldna [%o0] %asi, %o2
|
|
stn %o1, [%o0]
|
|
stna %o2, [%o0] %asi
|
|
slln %o3, 3, %o3
|
|
srln %o4, 8, %o4
|
|
sran %o5, 12, %o5
|
|
casn [%o0], %o1, %o2
|
|
casna [%o0] %asi, %o1, %o2
|
|
clrn %g1
|
|
@end example
|
|
|
|
In 32-bit mode @code{@value{AS}} will emit:
|
|
|
|
@example
|
|
ld [%o0], %o1
|
|
lda [%o0] %asi, %o2
|
|
st %o1, [%o0]
|
|
sta %o2, [%o0] %asi
|
|
sll %o3, 3, %o3
|
|
srl %o4, 8, %o4
|
|
sra %o5, 12, %o5
|
|
cas [%o0], %o1, %o2
|
|
casa [%o0] %asi, %o1, %o2
|
|
clr %g1
|
|
@end example
|
|
|
|
And in 64-bit mode @code{@value{AS}} will emit:
|
|
|
|
@example
|
|
ldx [%o0], %o1
|
|
ldxa [%o0] %asi, %o2
|
|
stx %o1, [%o0]
|
|
stxa %o2, [%o0] %asi
|
|
sllx %o3, 3, %o3
|
|
srlx %o4, 8, %o4
|
|
srax %o5, 12, %o5
|
|
casx [%o0], %o1, %o2
|
|
casxa [%o0] %asi, %o1, %o2
|
|
clrx %g1
|
|
@end example
|
|
|
|
Finally, the @samp{.nword} translating directive is supported
|
|
as well. It is documented in the section on Sparc machine
|
|
directives.
|
|
|
|
@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{nword} directive, SPARC
|
|
@item .nword
|
|
On the Sparc, the @code{.nword} directive produces native word sized value,
|
|
ie. if assembling with -32 it is equivalent to @code{.word}, if assembling
|
|
with -64 it is equivalent to @code{.xword}.
|
|
|
|
@cindex @code{proc} directive, SPARC
|
|
@item .proc
|
|
This directive is ignored. Any text following it on the same
|
|
line is also ignored.
|
|
|
|
@cindex @code{register} directive, SPARC
|
|
@item .register
|
|
This directive declares use of a global application or system register.
|
|
It must be followed by a register name %g2, %g3, %g6 or %g7, comma and
|
|
the symbol name for that register. If symbol name is @code{#scratch},
|
|
it is a scratch register, if it is @code{#ignore}, it just suppresses any
|
|
errors about using undeclared global register, but does not emit any
|
|
information about it into the object file. This can be useful e.g. if you
|
|
save the register before use and restore it after.
|
|
|
|
@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
|