+2012-10-23 Ian Bolton <ian.bolton@arm.com>
+ James Greenhalgh <james.greenhalgh@arm.com>
+ Jim MacArthur <jim.macarthur@arm.com>
+ Chris Schlumberger-Socha <chris.schlumberger-socha@arm.com>
+ Marcus Shawcroft <marcus.shawcroft@arm.com>
+ Nigel Stephens <nigel.stephens@arm.com>
+ Ramana Radhakrishnan <ramana.radhakrishnan@arm.com>
+ Richard Earnshaw <rearnsha@arm.com>
+ Sofiane Naci <sofiane.naci@arm.com>
+ Stephen Thomas <stephen,thomas@arm.com>
+ Tejas Belagod <tejas.belagod@arm.com>
+ Yufeng Zhang <yufeng.zhang@arm.com>
+
+ * doc/invoke.texi (AArch64 Options): New.
+ * doc/md.texi (Machine Constraints): Add AArch64.
+
2012-10-23 Ian Bolton <ian.bolton@arm.com>
James Greenhalgh <james.greenhalgh@arm.com>
Jim MacArthur <jim.macarthur@arm.com>
@c Try and put the significant identifier (CPU or system) first,
@c so users have a clue at guessing where the ones they want will be.
+@emph{AArch64 Options}
+@gccoptlist{-mbig-endian -mlittle-endian @gol
+-mgeneral-regs-only @gol
+-mcmodel=tiny -mcmodel=small -mcmodel=large @gol
+-mstrict-align @gol
+-momit-leaf-frame-pointer -mno-omit-leaf-frame-pointer @gol
+-mtls-dialect=desc -mtls-dialect=traditional @gol
+-march=@var{name} -mcpu=@var{name} -mtune=@var{name}}
+
@emph{Adapteva Epiphany Options}
@gccoptlist{-mhalf-reg-file -mprefer-short-insn-regs @gol
-mbranch-cost=@var{num} -mcmove -mnops=@var{num} -msoft-cmpsf @gol
@c in Machine Dependent Options
@menu
+* AArch64 Options::
* Adapteva Epiphany Options::
* ARM Options::
* AVR Options::
@end table
+@node AArch64 Options
+@subsection AArch64 Options
+@cindex AArch64 Options
+
+These options are defined for AArch64 implementations:
+
+@table @gcctabopt
+
+@item -mbig-endian
+@opindex mbig-endian
+Generate big-endian code. This is the default when GCC is configured for an
+@samp{aarch64_be-*-*} target.
+
+@item -mgeneral-regs-only
+@opindex mgeneral-regs-only
+Generate code which uses only the general registers.
+
+@item -mlittle-endian
+@opindex mlittle-endian
+Generate little-endian code. This is the default when GCC is configured for an
+@samp{aarch64-*-*} but not an @samp{aarch64_be-*-*} target.
+
+@item -mcmodel=tiny
+@opindex mcmodel=tiny
+Generate code for the tiny code model. The program and its statically defined
+symbols must be within 1GB of each other. Pointers are 64 bits. Programs can
+be statically or dynamically linked. This model is not fully implemented and
+mostly treated as @samp{small}.
+
+@item -mcmodel=small
+@opindex mcmodel=small
+Generate code for the small code model. The program and its statically defined
+symbols must be within 4GB of each other. Pointers are 64 bits. Programs can
+be statically or dynamically linked. This is the default code model.
+
+@item -mcmodel=large
+@opindex mcmodel=large
+Generate code for the large code model. This makes no assumptions about
+addresses and sizes of sections. Pointers are 64 bits. Programs can be
+statically linked only.
+
+@item -mstrict-align
+@opindex mstrict-align
+Do not assume that unaligned memory references will be handled by the system.
+
+@item -momit-leaf-frame-pointer
+@item -mno-omit-leaf-frame-pointer
+@opindex momit-leaf-frame-pointer
+@opindex mno-omit-leaf-frame-pointer
+Omit or keep the frame pointer in leaf functions. The former behaviour is the
+default.
+
+@item -mtls-dialect=desc
+@opindex mtls-dialect=desc
+Use TLS descriptors as the thread-local storage mechanism for dynamic accesses
+of TLS variables. This is the default.
+
+@item -mtls-dialect=traditional
+@opindex mtls-dialect=traditional
+Use traditional TLS as the thread-local storage mechanism for dynamic accesses
+of TLS variables.
+
+@item -march=@var{name}
+@opindex march
+Specify the name of the target architecture, optionally suffixed by one or
+more feature modifiers. This option has the form
+@option{-march=@var{arch}@r{@{}+@r{[}no@r{]}@var{feature}@r{@}*}}, where the
+only value for @var{arch} is @samp{armv8-a}. The possible values for
+@var{feature} are documented in the sub-section below.
+
+Where conflicting feature modifiers are specified, the right-most feature is
+used.
+
+GCC uses this name to determine what kind of instructions it can emit when
+generating assembly code. This option can be used in conjunction with or
+instead of the @option{-mcpu=} option.
+
+@item -mcpu=@var{name}
+@opindex mcpu
+Specify the name of the target processor, optionally suffixed by one or more
+feature modifiers. This option has the form
+@option{-mcpu=@var{cpu}@r{@{}+@r{[}no@r{]}@var{feature}@r{@}*}}, where the
+possible values for @var{cpu} are @samp{generic}, @samp{large}. The
+possible values for @var{feature} are documented in the sub-section
+below.
+
+Where conflicting feature modifiers are specified, the right-most feature is
+used.
+
+GCC uses this name to determine what kind of instructions it can emit when
+generating assembly code.
+
+@item -mtune=@var{name}
+@opindex mtune
+Specify the name of the processor to tune the performance for. The code will
+be tuned as if the target processor were of the type specified in this option,
+but still using instructions compatible with the target processor specified
+by a @option{-mcpu=} option. This option cannot be suffixed by feature
+modifiers.
+
+@end table
+
+@subsubsection @option{-march} and @option{-mcpu} feature modifiers
+@cindex @option{-march} feature modifiers
+@cindex @option{-mcpu} feature modifiers
+Feature modifiers used with @option{-march} and @option{-mcpu} can be one
+the following:
+
+@table @samp
+@item crypto
+Enable Crypto extension. This implies Advanced SIMD is enabled.
+@item fp
+Enable floating-point instructions.
+@item simd
+Enable Advanced SIMD instructions. This implies floating-point instructions
+are enabled. This is the default for all current possible values for options
+@option{-march} and @option{-mcpu=}.
+@end table
+
@node ARM Options
@subsection ARM Options
@cindex ARM options
the meanings of that architecture's constraints.
@table @emph
+@item AArch64 family---@file{config/aarch64/constraints.md}
+@table @code
+@item k
+The stack pointer register (@code{SP})
+
+@item w
+Floating point or SIMD vector register
+
+@item I
+Integer constant that is valid as an immediate operand in an @code{ADD}
+instruction
+
+@item J
+Integer constant that is valid as an immediate operand in a @code{SUB}
+instruction (once negated)
+
+@item K
+Integer constant that can be used with a 32-bit logical instruction
+
+@item L
+Integer constant that can be used with a 64-bit logical instruction
+
+@item M
+Integer constant that is valid as an immediate operand in a 32-bit @code{MOV}
+pseudo instruction. The @code{MOV} may be assembled to one of several different
+machine instructions depending on the value
+
+@item N
+Integer constant that is valid as an immediate operand in a 64-bit @code{MOV}
+pseudo instruction
+
+@item S
+An absolute symbolic address or a label reference
+
+@item Y
+Floating point constant zero
+
+@item Z
+Integer constant zero
+
+@item Usa
+An absolute symbolic address
+
+@item Ush
+The high part (bits 12 and upwards) of the pc-relative address of a symbol
+within 4GB of the instruction
+
+@item Q
+A memory address which uses a single base register with no offset
+
+@item Ump
+A memory address suitable for a load/store pair instruction in SI, DI, SF and
+DF modes
+
+@item Utf
+A memory address suitable for a load/store pair instruction in TF mode
+
+@end table
+
+
@item ARM family---@file{config/arm/constraints.md}
@table @code
@item w
projects / gcc.git / commitdiff