-@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},
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.
directive.
@c IIIIIIIIIIIIIIIIIIIIIIIIII
+
+@cindex @code{.inst} directive, ARM
+@item .inst @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.
+
@c JJJJJJJJJJJJJJJJJJJJJJJJJJ
@c KKKKKKKKKKKKKKKKKKKKKKKKKK
@c LLLLLLLLLLLLLLLLLLLLLLLLLL
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