armv6. It's too ambiguous. We do use the softfp ABI for the moment on
armv6, but we allow floating point register use (and the compilers
will generate it). This is too ambiguous to use it as a decider for
which algorithms to use on the platform. Err on the side of caution
and not define it.
Submitted by: ian@
Reviewed by: andrew@
float targets. It is added for booke on powerpc and all arm with hf in
the string. Also add arm to all arm builds and armv6 to armv6 and
newer builds.
PR: 202641
Clang emits SSE instructions on amd64 in the common path of
pthread_mutex_unlock. If the thread does not otherwise use SSE,
this usage incurs a context-switch of the FPU/SSE state, which
reduces the performance of multiple real-world applications by a
non-trivial amount (3-5% in one application).
Instead of this change, I experimented with eagerly switching the
FPU state at context-switch time. This did not help. Most of the
cost seems to be in the read/write of memory--as kib@ stated--and
not in the #NM handling. I tested on machines with and without
XSAVEOPT.
One counter-argument to this change is that most applications already
use SIMD, and the number of applications and amount of SIMD usage
are only increasing. This is absolutely true. I agree that--in
general and in principle--this change is in the wrong direction.
However, there are applications that do not use enough SSE to offset
the extra context-switch cost. SSE does not provide a clear benefit
in the current libthr code with the current compiler, but it does
provide a clear loss in some cases. Therefore, disabling SSE in
libthr is a non-loss for most, and a gain for some.
I refrained from disabling SSE in libc--as was suggested--because
I can't make the above argument for libc. It provides a wide variety
of code; each case should be analyzed separately.
https://lists.freebsd.org/pipermail/freebsd-current/2015-March/055193.html
Suggestions from: dim, jmg, rpaulo
Approved by: kib (mentor)
MFC after: 2 weeks
Sponsored by: Dell Inc.
use floating point hardware instructions (because all armv6/7 systems we
support have fp hardware), but it passes args using a soft-float compatible
ABI. This should give noticible performance improvement (but not as much
as using the armv6hf arch).
This includes:
o All directories named *ia64*
o All files named *ia64*
o All ia64-specific code guarded by __ia64__
o All ia64-specific makefile logic
o Mention of ia64 in comments and documentation
This excludes:
o Everything under contrib/
o Everything under crypto/
o sys/xen/interface
o sys/sys/elf_common.h
Discussed at: BSDcan
is useful primarily on a system used for cross-building, when you have a
set of flags to apply to the TARGET_ARCH being cross-built but don't want
those settings applied to building the cross-tools or other components that
run on the build host machine.
- Do not limit recent processors to "prescott" class for i386 target. There
is no reason for this hack because clang is default now. On top of that, it
will only grow indefinitely over time.
- Add more CPUTYPEs, i.e., "athlon-fx", "core-avx2", "atom", "penryn", and
"yonah". Note "penryn" and "yonah" are intentionally undocumented because
they are not supported by gcc and marked deprecated by clang.
- Add more CPUTYPE aliases, i.e., "barcelona" (-> amdfam10), "westmere" and
"nehalem" (-> corei7). Note these are intentionally undocumented because
they are not supported by (base) gcc and/or clang. However, LLVM (backend)
seems to "know" the differences. Most likely, they were deprecated with
other vendor code names and clang did not bother implementing them at all.
- Add i686 to MACHINE_CPU for "c3-2" (VIA Nehemiah). Both gcc & clang treat
it like an i686-class processor.
- Add IDT "winchip2" and "winchip-c6" for completeness (undocumented).
- Order processors per make.conf example, i.e., CPU vendors and models.
- Tidy up make.conf example, i.e., remove "by gcc" (because we have aliases)
and remove "prescott" from AMD64 architecture (because it is not correct).
r238211:
Support TARGET_ARCH=armv6 and TARGET_ARCH=armv6eb
This adds a new TARGET_ARCH for building on ARM
processors that support the ARMv6K multiprocessor
extensions. In particular, these processors have
better support for TLS and mutex operations.
This mostly touches a lot of Makefiles to extend
existing patterns for inferring CPUARCH from ARCH.
It also configures:
* GCC to default to arm1176jz-s
* GCC to predefine __FreeBSD_ARCH_armv6__
* gas to default to ARM_ARCH_V6K
* uname -p to return 'armv6'
* make so that MACHINE_ARCH defaults to 'armv6'
It also changes a number of headers to use
the compiler __ARM_ARCH_XXX__ macros to configure
processor-specific support routines.
Submitted by: Tim Kientzle <kientzle@freebsd.org>
This support has not worked for several years, and is not likely to work
again, unless Intel decides to release a native FreeBSD version of their
compiler. ;)
- add "sse3" to MACHINE_CPU for the new cpu types
- for i386, default to CPUTYPE=prescott for the new cpu types
PR: gnu/154906
Discussed with: kib, kan, dim
MFC after: 2 weeks
to let the compiler optimize for the famility of UltraSPARC-III CPUs as the
default already was to optimize for UltraSPARC-I/II and generating generic
64-bit V9 is mainly for reference purposes. At least for SPARC64-V CPUs
code optimized for UltraSPARC-I/II still is the most performant one.
Thanks go to Michael Moll for testing SPARC64-V.
- Move a booke MACHINE_CPU bit into the right section.
TARGET_BIG_ENDIAN is now completely dead, except where it was
originally supposed to be used (internally in the toolchain building).
TARGET_ARCH has changed in three cases:
(1) Little endian mips has changed to mipsel.
(2) Big endian mips has changed to mipseb.
(3) Big endian arm has changed to armeb.
Some additional changes are needed to make 'make universe' work on arm
and mips after this change, so those are commented out for now.
UPDATING information will be forthcoming. Any remaining rough edges
will be hammered out in -current.
available through MACHINE_CPU, indicating the CPU supports that
feature, as done by revision 138685.
This changeset adds "mmx" into the default amd64 MACHINE_CPU list
when no CPUTYPE is specified to provide consistent behavior.
PR: amd64/145593
Submitted by: mm
MFC after: 2 weeks
provided, for example, on the PowerPC 970 (G5), as well as on related CPUs
like the POWER3 and POWER4.
This also adds support for various built-in hardware found on Apple G5
hardware (e.g. the IBM CPC925 northbridge).
Reviewed by: grehan
The kernel config file is KERNCONF=MPC85XX, so the usual procedure applies:
1. make buildworld TARGET_ARCH=powerpc
2. make buildkernel TARGET_ARCH=powerpc TARGET_CPUTYPE=e500 KERNCONF=MPC85XX
This default config uses kernel-level FPU emulation. For the soft-float world
approach:
1. make buildworld TARGET_ARCH=powerpc TARGET_CPUTYPE=e500
2. disable FPU_EMU option in sys/powerpc/conf/MPC85XX
3. make buildkernel TARGET_ARCH=powerpc TARGET_CPUTYPE=e500 KERNCONF=MPC85XX
Approved by: cognet (mentor)
MFp4: e500
passed unmodified to gcc. Therefore, "prescott" should be used for Prescott,
Nocona, Core and Core 2 CPUs when building 32-bit code, and "nocona" should
be used for Prescott, Nocona and Core 2 CPUs when building 64-bit code.
MFC after: 3 weeks
