Linux commit ID ee988c11acf6f9464b7b44e9a091bf6afb3b3a49 reserved 2 new
bits in AT_HWCAP2:
- PPC_FEATURE2_ARCH_3_1 indicates the availability of the POWER ISA
3.1;
- PPC_FEATURE2_MMA indicates the availability of the Matrix-Multiply
Assist facility.
Alex Butler [Tue, 16 Jun 2020 12:44:24 +0000 (12:44 +0000)]
aarch64: MTE compatible strncmp
Add support for MTE to strncmp. Regression tested with xcheck and benchmarked
with glibc's benchtests on the Cortex-A53, Cortex-A72, and Neoverse N1.
The existing implementation assumes that any access to the pages in which the
string resides is safe. This assumption is not true when MTE is enabled. This
patch updates the algorithm to ensure that accesses remain within the bounds
of an MTE tag (16-byte chunks) and improves overall performance.
Alex Butler [Tue, 16 Jun 2020 12:42:38 +0000 (12:42 +0000)]
aarch64: MTE compatible strcmp
Add support for MTE to strcmp. Regression tested with xcheck and benchmarked
with glibc's benchtests on the Cortex-A53, Cortex-A72, and Neoverse N1.
The existing implementation assumes that any access to the pages in which the
string resides is safe. This assumption is not true when MTE is enabled. This
patch updates the algorithm to ensure that accesses remain within the bounds
of an MTE tag (16-byte chunks) and improves overall performance.
Alex Butler [Tue, 9 Jun 2020 16:09:36 +0000 (16:09 +0000)]
aarch64: MTE compatible strrchr
Add support for MTE to strrchr. Regression tested with xcheck and benchmarked
with glibc's benchtests on the Cortex-A53, Cortex-A72, and Neoverse N1.
The existing implementation assumes that any access to the pages in which the
string resides is safe. This assumption is not true when MTE is enabled. This
patch updates the algorithm to ensure that accesses remain within the bounds
of an MTE tag (16-byte chunks) and improves overall performance.
Alex Butler [Tue, 9 Jun 2020 16:08:07 +0000 (16:08 +0000)]
aarch64: MTE compatible memrchr
Add support for MTE to memrchr. Regression tested with xcheck and benchmarked
with glibc's benchtests on the Cortex-A53, Cortex-A72, and Neoverse N1.
The existing implementation assumes that any access to the pages in which the
string resides is safe. This assumption is not true when MTE is enabled. This
patch updates the algorithm to ensure that accesses remain within the bounds
of an MTE tag (16-byte chunks) and improves overall performance.
Alex Butler [Tue, 9 Jun 2020 16:06:03 +0000 (16:06 +0000)]
aarch64: MTE compatible memchr
Add support for MTE to memchr. Regression tested with xcheck and benchmarked
with glibc's benchtests on the Cortex-A53, Cortex-A72, and Neoverse N1.
The existing implementation assumes that any access to the pages in which the
string resides is safe. This assumption is not true when MTE is enabled. This
patch updates the algorithm to ensure that accesses remain within the bounds
of an MTE tag (16-byte chunks) and improves overall performance.
Alex Butler [Tue, 9 Jun 2020 15:57:03 +0000 (15:57 +0000)]
aarch64: MTE compatible strcpy
Add support for MTE to strcpy. Regression tested with xcheck and benchmarked
with glibc's benchtests on the Cortex-A53, Cortex-A72, and Neoverse N1.
The existing implementation assumes that any access to the pages in which the
string resides is safe. This assumption is not true when MTE is enabled. This
patch updates the algorithm to ensure that accesses remain within the bounds
of an MTE tag (16-byte chunks) and improves overall performance.
H.J. Lu [Wed, 17 Jun 2020 13:34:46 +0000 (06:34 -0700)]
x86: Update CPU feature detection [BZ #26149]
1. Divide architecture features into the usable features and the preferred
features. The usable features are for correctness and can be exported in
a stable ABI. The preferred features are for performance and only for
glibc internal use.
2. Change struct cpu_features to
struct cpu_features
{
struct cpu_features_basic basic;
unsigned int *usable_p;
struct cpuid_registers cpuid[COMMON_CPUID_INDEX_MAX];
unsigned int usable[USABLE_FEATURE_INDEX_MAX];
unsigned int preferred[PREFERRED_FEATURE_INDEX_MAX];
...
};
and initialize usable_p to pointer to the usable arary so that
can be exported via a stable ABI. The cpuid and usable arrays can be
expanded with backward binary compatibility for both .o and .so files.
3. Add COMMON_CPUID_INDEX_7_ECX_1 for AVX512_BF16.
4. Detect ENQCMD, PKS, AVX512_VP2INTERSECT, MD_CLEAR, SERIALIZE, HYBRID,
TSXLDTRK, L1D_FLUSH, CORE_CAPABILITIES and AVX512_BF16.
5. Rename CAPABILITIES to ARCH_CAPABILITIES.
6. Check if AVX512_VP2INTERSECT, AVX512_BF16 and PKU are usable.
7. Update CPU feature detection test.
Checked with a build for riscv64-linux-gnu-rv64imac-lp64 (no
builtin support), riscv64-linux-gnu-rv64imafdc-lp64, and
riscv64-linux-gnu-rv64imafdc-lp64d.
The powerpc sqrt implementation is also simplified:
- the static constants are open coded within the implementation.
- for !USE_SQRT_BUILTIN the function is implemented directly on
__ieee754_sqrt (it avoid an superflous extra jump).
Checked on powerpc-linux-gnu and powerpc64le-linux-gnu.
(all the issues wrong results for non default rounding modes).
The existing ia64 libm interface uses matherrf and matherrl in addition
to matherr for SVID error handling. However, there is no such error
handling support for exp10f in ia64 libm. So replacing it with the
generic implementation should be fine.
This patch changes the exp10f error handling semantics to only set
errno according to POSIX rules. New symbol version is introduced at
GLIBC_2.32. The old wrappers are kept for compat symbols.
There are some outliers that need special handling:
- ia64 provides an optimized implementation of exp10f that uses ia64
specific routines to set SVID compatibility. The new symbol version
is aliased to the exp10f one.
- m68k also provides an optimized implementation, and the new version
uses it instead of the sysdeps/ieee754/flt32 one.
- riscv and csky uses the generic template implementation that
does not provide SVID support. For both cases a new exp10f
version is not added, but rather the symbols version of the
generic sysdeps/ieee754/flt32 is adjusted instead.
Checked on aarch64-linux-gnu, x86_64-linux-gnu, i686-linux-gnu,
powerpc64le-linux-gnu.
Paul Zimmermann [Wed, 8 Apr 2020 20:32:28 +0000 (17:32 -0300)]
math: Optimized generic exp10f with wrappers
It is inspired by expf and reuses its tables and internal functions.
The error checks are inlined and errno setting is in separate tail
called functions, but the wrappers are kept in this patch to handle
the _LIB_VERSION==_SVID_ case.
Double precision arithmetics is used which is expected to be faster on
most targets (including soft-float) than using single precision and it
is easier to get good precision result with it.
strcmp-avx2.S: In avx2 strncmp function, strings are compared in
chunks of 4 vector size(i.e. 32x4=128 byte for avx2). After first 4
vector size comparison, code must check whether it already passed
the given offset. This patch implement avx2 offset check condition
for strncmp function, if both string compare same for first 4 vector
size.
Vineet Gupta [Fri, 8 Nov 2019 19:32:00 +0000 (11:32 -0800)]
ieee754/dbl-64: Reduce the scope of temporary storage variables
This came to light when adding hard-flaot support to ARC glibc port
without hardware sqrt support causing glibc build to fail:
| ../sysdeps/ieee754/dbl-64/e_sqrt.c: In function '__ieee754_sqrt':
| ../sysdeps/ieee754/dbl-64/e_sqrt.c:58:54: error: unused variable 'ty' [-Werror=unused-variable]
| double y, t, del, res, res1, hy, z, zz, p, hx, tx, ty, s;
The reason being EMULV() macro uses the hardware provided
__builtin_fma() variant, leaving temporary variables 'p, hx, tx, hy, ty'
unused hence compiler warning and ensuing error.
The intent of the patch was to fix that error, but EMULV is pervasive
and used fair bit indirectly via othe rmacros, hence this patch.
Functionally it should not result in code gen changes and if at all
those would be better since the scope of those temporaries is greatly
reduced now
Built tested with aarch64-linux-gnu arm-linux-gnueabi arm-linux-gnueabihf hppa-linux-gnu x86_64-linux-gnu arm-linux-gnueabihf riscv64-linux-gnu-rv64imac-lp64 riscv64-linux-gnu-rv64imafdc-lp64 powerpc-linux-gnu microblaze-linux-gnu nios2-linux-gnu hppa-linux-gnu
Also as suggested by Joseph [1] used --strip and compared the libs with
and w/o patch and they are byte-for-byte unchanged (with gcc 9).
| for i in `find . -name libm-2.31.9000.so`;
| do
| echo $i; diff $i /SCRATCH/vgupta/gnu2/install/glibcs/$i ; echo $?;
| done
Florian Weimer [Mon, 15 Jun 2020 07:50:14 +0000 (09:50 +0200)]
ld.so: Check for new cache format first and enhance corruption check
Now that ldconfig defaults to the new format (only), check for it
first. Also apply the corruption check added in commit 2954daf00bb4d
("Add more checks for valid ld.so.cache file (bug 18093)") to the
new-format-only case.
Samuel Thibault [Sun, 14 Jun 2020 17:44:57 +0000 (17:44 +0000)]
hurd: Fix __writev_nocancel_nostatus
* sysdeps/mach/hurd/Makefile [subdir=misc] (sysdep_routines): Add
writev_nocancel writev_nocancel_nostatus.
* sysdeps/mach/hurd/not-cancel.h (__writev_nocancel_nostatus): Replace
macro with function declaration (with hidden prototype in libc).
(__writev_nocancel): New function declaration (with hidden prototype in libc).
* sysdeps/mach/hurd/writev_nocancel_nostatus.c: New file.
* sysdeps/posix/writev_nocancel.c: New file, includes writev.c to make a
nocancel variant that calls __write_nocancel.
* sysdeps/posix/writev.c (writev): Do not define alias if __writev is
renamed.
Samuel Thibault [Sun, 14 Jun 2020 15:50:44 +0000 (15:50 +0000)]
hurd: Make write and pwrite64 cancellation points
and add _nocancel variants.
* sysdeps/mach/hurd/write.c (__libc_write): Call __write_nocancel
surrounded by enabling async cancel, to replace implementation moved
to...
* sysdeps/mach/hurd/write_nocancel.c (__write_nocancel): ... here.
* sysdeps/mach/hurd/pwrite64.c (__libc_pwrite64): Call
__pwrite64_nocancel surrounded by enabling async cancel, to replace
implementation moved to...
* sysdeps/mach/hurd/pwrite64_nocancel.c (__pwrite64_nocancel): ... here.
* sysdeps/mach/hurd/Makefile (sysdep_routines): Add write_nocancel and
pwrite64_nocancel.
* sysdeps/mach/hurd/not-cancel.h (__write_nocancel,
__pwrite64_nocancel): Replace macros with prototypes with a hidden proto on
libc.
* sysdeps/mach/hurd/dl-sysdep.c (__write_nocancel): New alias, check
that it is not hidden.
* sysdeps/mach/hurd/Versions (libc.GLIBC_PRIVATE): Add __write_nocancel.
(ld.GLIBC_PRIVATE): Add __write_nocancel.
* sysdeps/mach/hurd/i386/localplt.data (__write_nocancel): Add
reference.
Samuel Thibault [Sun, 14 Jun 2020 14:48:07 +0000 (14:48 +0000)]
htl: Fix cleanup support for IO locking
* sysdeps/htl/stdio-lock.h: New file, registers locking cleanup to htl.
* sysdeps/htl/libc-lockP.h: Include <libc-lock.h>.
(__libc_cleanup_region_start, __libc_cleanup_end,
__libc_cleanup_region_end): Override macros from <libc-lock.h> with
versions which register cleanup to htl.
(__pthread_get_cleanup_stack): Make reference weak for skipping
registration on in the static non-libpthread case.
Samuel Thibault [Sun, 14 Jun 2020 12:56:54 +0000 (12:56 +0000)]
htl: Move cleanup stack to variable shared between libc and pthread
If libpthread gets loaded dynamically, the stack needs to already contain the
cleanup handlers of the main thread.
* htl/libc_pthread_init.c (__pthread_cleanup_stack): New per-thread variable.
* htl/Versions (libc): Add __pthread_cleanup_stack as private symbol.
* htl/pt-internal.h (struct __pthread): Remove cancelation_handlers
field.
(__pthread_cleanup_stack): Add variable declaration.
* htl/pt-alloc.c (initialize_pthread): Remove initialization of
cancelation_handlers field.
* htl/pt-cleanup.c (__pthread_get_cleanup_stack): Return the address of
__pthread_cleanup_stack instead of that of the cancelation_handlers
field.
* htl/forward.c: Include <pt-internal.h>.
(dummy_list): Remove variable.
(__pthread_get_cleanup_stack): Return the address of __pthread_cleanup_stack
instead of that of dummy_list.
Samuel Thibault [Sun, 14 Jun 2020 00:19:35 +0000 (00:19 +0000)]
hurd: Make recv* cancellation points
* sysdeps/mach/hurd/recv.c (__recv): Make the __socket_recv call
cancellable.
* sysdeps/mach/hurd/recvfrom.c (__recvfrom): Make the __socket_recv and
__socket_whatis_address calls cancellable.
* sysdeps/mach/hurd/recvmsg.c (__libc_recvmsg): Make the __socket_recv,
__socket_whatis_address, __io_reauthenticate, and __auth_user_authenticate calls
cancellable.
Paul E. Murphy [Fri, 8 May 2020 13:27:56 +0000 (08:27 -0500)]
powerpc: Automatic CPU detection in preconfigure
Added a check to detect the CPU value in preconfigure, so that glibc is
built with the correct --with-cpu value. And move existing checks into
preconfigure.ac.
Co-Authored-By: Carlos Eduardo Seo <cseo@linux.vnet.ibm.com> Co-Authored-By: Tulio Magno Quites Machado Filho <tuliom@linux.vnet.ibm.com>
Samuel Thibault [Wed, 10 Jun 2020 20:03:52 +0000 (20:03 +0000)]
htl: Fix linking static tests by factorizing the symbols list
libpthread_syms.a will contain the symbols that libc tries to get from
libpthread, to be used by the system, but also by tests.
* htl/libpthread.a, htl/libpthread_pic.a: Link libpthread_syms.a and Move EXTERN
references to...
* htl/libpthread_syms.a: ... new file. Add missing
__pthread_enable_asynccancel reference.
* htl/Makefile: Install libpthread_syms.a and link it into static tests.
Andrea Corallo [Fri, 5 Jun 2020 15:22:26 +0000 (17:22 +0200)]
aarch64: MTE compatible strlen
Introduce an Arm MTE compatible strlen implementation.
The existing implementation assumes that any access to the pages in
which the string resides is safe. This assumption is not true when
MTE is enabled. This patch updates the algorithm to ensure that
accesses remain within the bounds of an MTE tag (16-byte chunks) and
improves overall performance on modern cores. On cores with less
efficient Advanced SIMD implementation such as Cortex-A53 it can
be slower.
Benchmarked on Cortex-A72, Cortex-A53, Neoverse N1.
Andrea Corallo [Fri, 5 Jun 2020 15:20:50 +0000 (17:20 +0200)]
aarch64: MTE compatible strchr
Introduce an Arm MTE compatible strchr implementation.
The existing implementation assumes that any access to the pages in
which the string resides is safe. This assumption is not true when
MTE is enabled. This patch updates the algorithm to ensure that
accesses remain within the bounds of an MTE tag (16-byte chunks) and
improves overall performance.
Benchmarked on Cortex-A72, Cortex-A53, Neoverse N1.
Andrea Corallo [Fri, 5 Jun 2020 15:18:49 +0000 (17:18 +0200)]
aarch64: MTE compatible strchrnul
Introduce an Arm MTE compatible strchrnul implementation.
The existing implementation assumes that any access to the pages in
which the string resides is safe. This assumption is not true when
MTE is enabled. This patch updates the algorithm to ensure that
accesses remain within the bounds of an MTE tag (16-byte chunks) and
improves overall performance.
Benchmarked on Cortex-A72, Cortex-A53, Neoverse N1.
Krzysztof Koch [Mon, 8 Jun 2020 13:06:15 +0000 (14:06 +0100)]
AArch64: Merge Falkor memcpy and memmove implementations
Falkor's memcpy and memmove share some implementation details,
therefore, the two routines are moved to a single source file
for code reuse.
The two routines now share code for small and medium copies
(up to and including 128 bytes). Large copies in memcpy do not
handle overlap correctly, consequently, the loops for
moving/copying more than 128 bytes stay separate for memcpy
and memmove.
To increase code reuse a number of small modifications were made:
1. The old implementation of memcpy copied the first 16-bytes as
soon as the size of data was determined to be greater than 32 bytes.
For memcpy code to also work when copying small/medium overlapping
data, the first load and store was moved to the large copy case.
2. Medium memcpy case no longer assumes that 16 bytes were already
copied and uses 8 registers to copy up to 128 bytes.
3. Small case for memmove was enlarged to that of memcpy, which is
less than or equal to 32 bytes.
4. Medium case for memmove was enlarged to that of memcpy, which is
less than or equal to 128 bytes.
Other changes include:
1. Improve alignment of existing loop bodies.
2. 'Delouse' memmove and memcpy input arguments. Make sure that
upper 32-bits of input registers are zeroed if unused.
3. Do one more iteration in memmove loops and reduce the number of
copies made from the start/end of the buffer, depending on
the direction of the memmove loop.
Benchmarking:
Looking at the results from bench-memcpy-random.out, we can see that
now memmove_falkor is about 5% faster than memcpy_falkor_old, while
memmove_falkor_old was more than 15% slower. The memcpy implementation
remained largely unmodified, so there is no significant performance
change.
The reason for such a significant memmove performance gain is the
increase of the upper bound on the small copy case to 32 bytes and
the increase of the upper bound on the medium copy case to 128 bytes.
Samuel Thibault [Mon, 8 Jun 2020 11:32:08 +0000 (13:32 +0200)]
pthread: Move back linking rules to nptl and htl
d6d74ec16 ('htl: Enable more tests') moved the linking rules from
nptl/Makefile and htl/Makefile to the shared sysdeps/pthread/Makefile. But
e.g. on powerpc some tests are added in sysdeps/powerpc/Makefile, which is
included *after* sysdeps/pthread/Makefile, and thus the tests don't get
affected by the rules and fail to link. For now let's just copy over the
set of rules in both nptl/Makefile and htl/Makefile.
Samuel Thibault [Sun, 7 Jun 2020 23:27:46 +0000 (23:27 +0000)]
htl: Fix tls initialization for already-created threads
* sysdeps/htl/pthreadP.h: Include <link.h>
(__pthread_init_static_tls): New prototype.
* htl/pt-alloc.c (__pthread_init_static_tls): New function.
* sysdeps/mach/hurd/htl/pt-sysdep.c (_init_routine): Initialize tcb
field of initial thread. Set GL(dl_init_static_tls) to
&__pthread_init_static_tls.
Samuel Thibault [Sun, 7 Jun 2020 23:16:46 +0000 (23:16 +0000)]
hurd: Make read and pread64 cancellable
and add _nocancel variants.
* sysdeps/mach/hurd/pread64.c (__libc_pread64): Call __pread64_nocancel
surrounded by enabling async cancel, to replace implementation moved to...
* sysdeps/mach/hurd/pread64_nocancel.c (__pread64_nocancel): ... here.
* sysdeps/mach/hurd/read.c (__libc_read): Call __read_nocancel surrounded by
enabling async cancel, to replace implementation moved to...
* sysdeps/mach/hurd/read_nocancel.c (__read_nocancel): ... here.
* sysdeps/mach/hurd/Makefile (sysdep_routines): Add read_nocancel and
pread64_nocancel.
* sysdeps/mach/hurd/not-cancel.h (__read_nocancel, __pread64_nocancel):
Replace macros with prototypes with a hidden proto on libc.
* sysdeps/mach/hurd/dl-sysdep.c: Include <not-cancel.h>.
(__pread64_nocancel): New alias, check that it is not hidden.
(__read_nocancel): New alias, check that it is not hidden.
Samuel Thibault [Sun, 7 Jun 2020 02:03:45 +0000 (02:03 +0000)]
htl: Enable more tests
* htl/Makefile: Remove rules adding libpthread.so and libpthread.a to link
lines.
* nptl/Makefile: Move rules adding libpthread.so and libpthread.a to
link lines to...
* sysdeps/pthread/Makefile: ... here.
Samuel Thibault [Sat, 6 Jun 2020 18:21:22 +0000 (20:21 +0200)]
hurd: fix clearing SS_ONSTACK when longjmp-ing from sighandler
* sysdeps/i386/htl/Makefile: New file.
* sysdeps/i386/htl/tcb-offsets.sym: New file.
* sysdeps/mach/hurd/i386/Makefile [setjmp] (gen-as-const-headers): Add
signal-defines.sym.
* sysdeps/mach/hurd/i386/____longjmp_chk.S: Include tcb-offsets.h.
(____longjmp_chk): Harmonize with i386's __longjmp. Clear SS_ONSTACK
when jumping off the alternate stack.
* sysdeps/mach/hurd/i386/__longjmp.S: New file.
Vineet Gupta [Wed, 27 May 2020 19:54:21 +0000 (12:54 -0700)]
dl-runtime: reloc_{offset,index} now functions arch overide'able
The existing macros are fragile and expect local variables with a
certain name. Fix this by defining them as functions with default
implementation in a new header dl-runtime.h which arches can override
if need be.
This came up during ARC port review, hence the need for argument pltgot
in reloc_index() which is not needed by existing ports.
This patch potentially only affects hppa/x86 ports,
build tested for both those configs and a few more.
Paul E. Murphy [Mon, 18 May 2020 16:16:06 +0000 (11:16 -0500)]
powerpc64le: add optimized strlen for P9
This started as a trivial change to Anton's rawmemchr. I got
carried away. This is a hybrid between P8's asympotically
faster 64B checks with extremely efficient small string checks
e.g <64B (and sometimes a little bit more depending on alignment).
The second trick is to align to 64B by running a 48B checking loop
16B at a time until we naturally align to 64B (i.e checking 48/96/144
bytes/iteration based on the alignment after the first 5 comparisons).
This allieviates the need to check page boundaries.
Finally, explicly use the P7 strlen with the runtime loader when building
P9. We need to be cautious about vector/vsx extensions here on P9 only
builds.
Paul E. Murphy [Wed, 3 Jun 2020 18:57:20 +0000 (13:57 -0500)]
powerpc64le: use common fmaf128 implementation
This defines the macro such that it should behave best on all
supported powerpc targets. Likewise, this allows us to remove the
ppc64le specific s_fmaf128.c.
I have verified powerpc64le multiarch and powerpc64le power9
no-multiarch builds continue to generate optimize fmaf128.
y2038: Replace __clock_gettime with __clock_gettime64
breaks benchtests with sysdeps/generic/hp-timing.h:
In file included from ./bench-timing.h:23,
from ./bench-skeleton.c:25,
from
/export/build/gnu/tools-build/glibc-gitlab/build-x86_64-linux/benchtests/bench-rint.c:45:
./bench-skeleton.c: In function ‘main’:
../sysdeps/generic/hp-timing.h:37:23: error: storage size of ‘tv’ isn’t known
37 | struct __timespec64 tv; \
| ^~
Define HP_TIMING_NOW with clock_gettime in sysdeps/generic/hp-timing.h
if _ISOMAC is defined. Don't define __clock_gettime in bench-timing.h
since it is no longer needed.
Samuel Thibault [Thu, 4 Jun 2020 18:52:19 +0000 (20:52 +0200)]
support: Fix detecting hole support on >2KB-block filesystems
When detecting hole support, we write at 16MiB, and filesystems will
typically need two levels of data to record that. On filesystems with
8KB block, the two indirection blocks will require a total of 16KB
overhead, thus 32 512-byte sectors.
Spotted on GNU/Hurd with a 4KB blocks filesystem, but also happens on Linux
with 4KB or 8KB blocks filesystems.
* support/support_descriptor_supports_holes.c
(support_descriptor_supports_holes): Set block_headroom to 32.
Vineet Gupta [Fri, 29 May 2020 23:12:44 +0000 (16:12 -0700)]
powerpc/fpu: use generic fma functions
Tested with build-many-glibcs for powerpc-linux-gnu
This is a non functional change and powerpc libm before/after was
byte invariant as compared below:
| cd /SCRATCH/vgupta/gnu/install-glibc-A-baseline
| for i in `find . -name libm-2.31.9000.so`; do
| echo $i; diff $i /SCRATCH/vgupta/gnu/install-glibc-C-reduce-scope/$i ;
| echo $?;
| done
Vineet Gupta [Fri, 29 May 2020 23:06:59 +0000 (16:06 -0700)]
aarch/fpu: use generic builtins based math functions
introduce sysdep header math-use-builtins.h to replace aarch64
implementations with corresponding generic ones.
- newly inroduced generic sqrt{,f}, fma{,f}
- existing floor{,f}, nearbyint{,f}, rint{,f}, round{,f}, trunc{,f}
- Note that generic copysign was already enabled (via generic
math-use-builtins.h) now thru sysdep header
Tested with build-many-glibcs for aarch64-linux-gnu
This is a non functional change and aarch64 libm before/after was
byte invariant as compared below:
| cd /SCRATCH/vgupta/gnu/install-glibc-A-baseline
| for i in `find . -name libm-2.31.9000.so`; do
| echo $i; diff $i /SCRATCH/vgupta/gnu/install-glibc-C-reduce-scope/$i ;
| echo $?;
| done
Florian Weimer [Mon, 18 May 2020 16:25:18 +0000 (18:25 +0200)]
nptl: Change type of __default_pthread_attr
union pthread_attr_transparent has always the correct size, even if
pthread_attr_t has padding that is not present in struct pthread_attr.
This should not result in an observable behavioral change. The
existing code appears to have been correct, but it was brittle because
it was not clear which functions were allowed to write to an entire
pthread_attr_t argument (e.g., by copying it).