-@c Copyright 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
-@c 2008, 2009 Free Software Foundation, Inc.
+@c Copyright 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
+@c 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
@c This is part of the GAS manual.
@c For copying conditions, see the file as.texinfo.
@code{arm1020e},
@code{arm1022e},
@code{arm1026ej-s},
+@code{fa606te} (Faraday FA606TE processor),
+@code{fa616te} (Faraday FA616TE processor),
@code{fa626te} (Faraday FA626TE processor),
+@code{fmp626} (Faraday FMP626 processor),
@code{fa726te} (Faraday FA726TE processor),
@code{arm1136j-s},
@code{arm1136jf-s},
@code{arm1176jzf-s},
@code{mpcore},
@code{mpcorenovfp},
+@code{cortex-a5},
+@code{cortex-a7},
@code{cortex-a8},
@code{cortex-a9},
+@code{cortex-a15},
@code{cortex-r4},
+@code{cortex-r4f},
+@code{cortex-m4},
@code{cortex-m3},
@code{cortex-m1},
@code{cortex-m0},
+@code{cortex-m0plus},
@code{ep9312} (ARM920 with Cirrus Maverick coprocessor),
@code{i80200} (Intel XScale processor)
@code{iwmmxt} (Intel(r) XScale processor with Wireless MMX(tm) technology coprocessor)
In addition to the basic instruction set, the assembler can be told to
accept various extension mnemonics that extend the processor using the
co-processor instruction space. For example, @code{-mcpu=arm920+maverick}
-is equivalent to specifying @code{-mcpu=ep9312}. The following extensions
-are currently supported:
-@code{+maverick}
-@code{+iwmmxt}
+is equivalent to specifying @code{-mcpu=ep9312}.
+
+Multiple extensions may be specified, separated by a @code{+}. The
+extensions should be specified in ascending alphabetical order.
+
+Some extensions may be restricted to particular architectures; this is
+documented in the list of extensions below.
+
+Extension mnemonics may also be removed from those the assembler accepts.
+This is done be prepending @code{no} to the option that adds the extension.
+Extensions that are removed should be listed after all extensions which have
+been added, again in ascending alphabetical order. For example,
+@code{-mcpu=ep9312+nomaverick} is equivalent to specifying @code{-mcpu=arm920}.
+
+
+The following extensions are currently supported:
+@code{idiv}, (Integer Divide Extensions for v7-A and v7-R architectures),
+@code{iwmmxt},
+@code{iwmmxt2},
+@code{maverick},
+@code{mp} (Multiprocessing Extensions for v7-A and v7-R architectures),
+@code{os} (Operating System for v6M architecture),
+@code{sec} (Security Extensions for v6K and v7-A architectures),
+@code{virt} (Virtualization Extensions for v7-A architecture, implies
+@code{idiv}),
and
-@code{+xscale}.
+@code{xscale}.
@cindex @code{-march=} command line option, ARM
@item -march=@var{architecture}[+@var{extension}@dots{}]
@code{armv6k},
@code{armv6z},
@code{armv6zk},
+@code{armv6-m},
+@code{armv6s-m},
@code{armv7},
@code{armv7-a},
@code{armv7-r},
@code{armv7-m},
+@code{armv7e-m},
@code{iwmmxt}
and
@code{xscale}.
@code{vfp10-r0},
@code{vfp9},
@code{vfpxd},
-@code{vfpv2}
-@code{vfpv3}
-@code{vfpv3-d16}
+@code{vfpv2},
+@code{vfpv3},
+@code{vfpv3-fp16},
+@code{vfpv3-d16},
+@code{vfpv3-d16-fp16},
+@code{vfpv3xd},
+@code{vfpv3xd-d16},
+@code{vfpv4},
+@code{vfpv4-d16},
+@code{fpv4-sp-d16},
@code{arm1020t},
@code{arm1020e},
@code{arm1136jf-s},
-@code{maverick}
+@code{maverick},
+@code{neon},
and
-@code{neon}.
+@code{neon-vfpv4}.
In addition to determining which instructions are assembled, this option
also affects the way in which the @code{.double} assembler directive behaves
This option specifies that the output generated by the assembler should
be marked as supporting interworking.
-@cindex @code{-mauto-it} command line option, ARM
-@item -mauto-it
-This option enables the automatic generation of IT instructions for
-conditional instructions not covered by an IT block.
-
-@cindex @code{-mapcs} command line option, ARM
-@item -mapcs @code{[26|32]}
-This option specifies that the output generated by the assembler should
+@cindex @code{-mimplicit-it} command line option, ARM
+@item -mimplicit-it=never
+@itemx -mimplicit-it=always
+@itemx -mimplicit-it=arm
+@itemx -mimplicit-it=thumb
+The @code{-mimplicit-it} option controls the behavior of the assembler when
+conditional instructions are not enclosed in IT blocks.
+There are four possible behaviors.
+If @code{never} is specified, such constructs cause a warning in ARM
+code and an error in Thumb-2 code.
+If @code{always} is specified, such constructs are accepted in both
+ARM and Thumb-2 code, where the IT instruction is added implicitly.
+If @code{arm} is specified, such constructs are accepted in ARM code
+and cause an error in Thumb-2 code.
+If @code{thumb} is specified, such constructs cause a warning in ARM
+code and are accepted in Thumb-2 code. If you omit this option, the
+behavior is equivalent to @code{-mimplicit-it=arm}.
+
+@cindex @code{-mapcs-26} command line option, ARM
+@cindex @code{-mapcs-32} command line option, ARM
+@item -mapcs-26
+@itemx -mapcs-32
+These options specify that the output generated by the assembler should
be marked as supporting the indicated version of the Arm Procedure.
Calling Standard.
@node ARM Syntax
@section Syntax
@menu
+* ARM-Instruction-Set:: Instruction Set
* ARM-Chars:: Special Characters
* ARM-Regs:: Register Names
* ARM-Relocations:: Relocations
+* ARM-Neon-Alignment:: NEON Alignment Specifiers
@end menu
+@node ARM-Instruction-Set
+@subsection Instruction Set Syntax
+Two slightly different syntaxes are support for ARM and THUMB
+instructions. The default, @code{divided}, uses the old style where
+ARM and THUMB instructions had their own, separate syntaxes. The new,
+@code{unified} syntax, which can be selected via the @code{.syntax}
+directive, and has the following main features:
+
+@table @bullet
+@item
+Immediate operands do not require a @code{#} prefix.
+
+@item
+The @code{IT} instruction may appear, and if it does it is validated
+against subsequent conditional affixes. In ARM mode it does not
+generate machine code, in THUMB mode it does.
+
+@item
+For ARM instructions the conditional affixes always appear at the end
+of the instruction. For THUMB instructions conditional affixes can be
+used, but only inside the scope of an @code{IT} instruction.
+
+@item
+All of the instructions new to the V6T2 architecture (and later) are
+available. (Only a few such instructions can be written in the
+@code{divided} syntax).
+
+@item
+The @code{.N} and @code{.W} suffixes are recognized and honored.
+
+@item
+All instructions set the flags if and only if they have an @code{s}
+affix.
+@end table
+
@node ARM-Chars
@subsection Special Characters
@cindex line comment character, ARM
@cindex ARM 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.
+The presence of a @samp{@@} anywhere on a line indicates the start of
+a comment that extends to the end of that line.
+
+If a @samp{#} appears as the first character of a line then the whole
+line is treated as a comment, but in this case the line could also be
+a logical line number directive (@pxref{Comments}) or a preprocessor
+control command (@pxref{Preprocessing}).
@cindex line separator, ARM
@cindex statement separator, ARM
@cindex register names, ARM
*TODO* Explain about ARM register naming, and the predefined names.
+@node ARM-Neon-Alignment
+@subsection NEON Alignment Specifiers
+
+@cindex alignment for NEON instructions
+Some NEON load/store instructions allow an optional address
+alignment qualifier.
+The ARM documentation specifies that this is indicated by
+@samp{@@ @var{align}}. However GAS already interprets
+the @samp{@@} character as a "line comment" start,
+so @samp{: @var{align}} is used instead. For example:
+
+@smallexample
+ vld1.8 @{q0@}, [r0, :128]
+@end smallexample
+
@node ARM Floating Point
@section Floating Point
@code{TLSGD},
@code{TLSLDM},
@code{TLSLDO},
-@code{GOTTPOFF}
+@code{TLSDESC},
+@code{TLSCALL},
+@code{GOTTPOFF},
+@code{GOT_PREL}
and
@code{TPOFF}.
For compatibility with older toolchains the assembler also accepts
-@code{(PLT)} after branch targets. This will generate the deprecated
-@samp{R_ARM_PLT32} relocation.
+@code{(PLT)} after branch targets. On legacy targets this will
+generate the deprecated @samp{R_ARM_PLT32} relocation. On EABI
+targets it will encode either the @samp{R_ARM_CALL} or
+@samp{R_ARM_JUMP24} relocation, as appropriate.
@cindex MOVW and MOVT relocations, ARM
Relocations for @samp{MOVW} and @samp{MOVT} instructions can be generated
Select the target architecture. Valid values for @var{name} are the same as
for the @option{-march} commandline option.
+Specifying @code{.arch} clears any previously selected architecture
+extensions.
+
+@cindex @code{.arch_extension} directive, ARM
+@item .arch_extension @var{name}
+Add or remove an architecture extension to the target architecture. Valid
+values for @var{name} are the same as those accepted as architectural
+extensions by the @option{-mcpu} commandline option.
+
+@code{.arch_extension} may be used multiple times to add or remove extensions
+incrementally to the architecture being compiled for.
+
@cindex @code{.arm} directive, ARM
@item .arm
This performs the same action as @var{.code 32}.
Select the target processor. Valid values for @var{name} are the same as
for the @option{-mcpu} commandline option.
+Specifying @code{.cpu} clears any previously selected architecture
+extensions.
+
@c DDDDDDDDDDDDDDDDDDDDDDDDDD
@cindex @code{.dn} and @code{.qn} directives, ARM
@item @var{name} .dn @var{register name} [@var{.type}] [[@var{index}]]
-@item @var{name} .qn @var{register name} [@var{.type}] [[@var{index}]]
+@itemx @var{name} .qn @var{register name} [@var{.type}] [[@var{index}]]
The @code{dn} and @code{qn} directives are used to create typed
and/or indexed register aliases for use in Advanced SIMD Extension
The @var{tag} is either an attribute number, or one of the following:
@code{Tag_CPU_raw_name}, @code{Tag_CPU_name}, @code{Tag_CPU_arch},
@code{Tag_CPU_arch_profile}, @code{Tag_ARM_ISA_use},
-@code{Tag_THUMB_ISA_use}, @code{Tag_VFP_arch}, @code{Tag_WMMX_arch},
+@code{Tag_THUMB_ISA_use}, @code{Tag_FP_arch}, @code{Tag_WMMX_arch},
@code{Tag_Advanced_SIMD_arch}, @code{Tag_PCS_config},
@code{Tag_ABI_PCS_R9_use}, @code{Tag_ABI_PCS_RW_data},
@code{Tag_ABI_PCS_RO_data}, @code{Tag_ABI_PCS_GOT_use},
@code{Tag_ABI_PCS_wchar_t}, @code{Tag_ABI_FP_rounding},
@code{Tag_ABI_FP_denormal}, @code{Tag_ABI_FP_exceptions},
@code{Tag_ABI_FP_user_exceptions}, @code{Tag_ABI_FP_number_model},
-@code{Tag_ABI_align8_needed}, @code{Tag_ABI_align8_preserved},
+@code{Tag_ABI_align_needed}, @code{Tag_ABI_align_preserved},
@code{Tag_ABI_enum_size}, @code{Tag_ABI_HardFP_use},
@code{Tag_ABI_VFP_args}, @code{Tag_ABI_WMMX_args},
@code{Tag_ABI_optimization_goals}, @code{Tag_ABI_FP_optimization_goals},
@code{Tag_compatibility}, @code{Tag_CPU_unaligned_access},
-@code{Tag_VFP_HP_extension}, @code{Tag_ABI_FP_16bit_format},
+@code{Tag_FP_HP_extension}, @code{Tag_ABI_FP_16bit_format},
+@code{Tag_MPextension_use}, @code{Tag_DIV_use},
@code{Tag_nodefaults}, @code{Tag_also_compatible_with},
@code{Tag_conformance}, @code{Tag_T2EE_use},
-@code{Tag_Virtualization_use}, @code{Tag_MPextension_use}
+@code{Tag_Virtualization_use}
The @var{value} is either a @code{number}, @code{"string"}, or
@code{number, "string"} depending on the tag.
+Note - the following legacy values are also accepted by @var{tag}:
+@code{Tag_VFP_arch}, @code{Tag_ABI_align8_needed},
+@code{Tag_ABI_align8_preserved}, @code{Tag_VFP_HP_extension},
+
@cindex @code{.even} directive, ARM
@item .even
This directive aligns to an even-numbered address.
@cindex @code{.inst} directive, ARM
@item .inst @var{opcode} [ , @dots{} ]
-@item .inst.n @var{opcode} [ , @dots{} ]
-@item .inst.w @var{opcode} [ , @dots{} ]
+@itemx .inst.n @var{opcode} [ , @dots{} ]
+@itemx .inst.w @var{opcode} [ , @dots{} ]
Generates the instruction corresponding to the numerical value @var{opcode}.
@code{.inst.n} and @code{.inst.w} allow the Thumb instruction size to be
specified explicitly, overriding the normal encoding rules.
Make all unwinder annotations relative to a frame pointer. Without this
the unwinder will use offsets from the stack pointer.
-The syntax of this directive is the same as the @code{sub} or @code{mov}
+The syntax of this directive is the same as the @code{add} or @code{mov}
instruction used to set the frame pointer. @var{spreg} must be either
@code{sp} or mentioned in a previous @code{.movsp} directive.
mov ip, sp
@dots{}
.setfp fp, ip, #4
-sub fp, ip, #4
+add fp, ip, #4
@end smallexample
@cindex @code{.secrel32} directive, ARM
offset of each expression's symbol. This directive is only supported
for PE targets.
+@cindex @code{.syntax} directive, ARM
+@item .syntax [@code{unified} | @code{divided}]
+This directive sets the Instruction Set Syntax as described in the
+@ref{ARM-Instruction-Set} section.
+
@c TTTTTTTTTTTTTTTTTTTTTTTTTT
@cindex @code{.thumb} directive, ARM
the aliased symbol as being a thumb function entry point, in the same
way that the @code{.thumb_func} directive does.
+@cindex @code{.tlsdescseq} directive, ARM
+@item .tlsdescseq @var{tls-variable}
+This directive is used to annotate parts of an inlined TLS descriptor
+trampoline. Normally the trampoline is provided by the linker, and
+this directive is not needed.
+
@c UUUUUUUUUUUUUUUUUUUUUUUUUU
@cindex @code{.unreq} directive, ARM
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