Hi, as I wrote in previous patches a performance of checked strcpy and
stpcpy is terrible as these don't use sse2 and are around four times
slower that strcpy and stpcpy now.
As this bug shows that these functions are not performance sensitive I
decided just to improve generic implementation instead for easier
maintainance.
* debug/strcpy_chk.c: Improve performance.
* debug/stpcpy_chk.c: Likewise.
* sysdeps/x86_64/strcpy_chk.S: Remove.
* sysdeps/x86_64/stpcpy_chk.S: Remove.
This patch adds SSE, AVX and AVX512 versions of _dl_runtime_resolve
and _dl_runtime_profile, which save and restore the first 8 vector
registers used for parameter passing. elf_machine_runtime_setup
selects the proper _dl_runtime_resolve or _dl_runtime_profile based
on _dl_x86_cpu_features. It avoids race condition caused by
FOREIGN_CALL macros, which are only used for x86-64.
Performance impact of saving and restoring 8 vector registers are
negligible on Nehalem, Sandy Bridge, Ivy Bridge and Haswell when
ld.so is optimized with SSE2.
[BZ #15128]
* sysdeps/x86_64/Makefile [$(subdir) == elf] (tests): Add
ifuncmain8.
(modules-names): Add ifuncmod8.
($(objpfx)ifuncmain8): New rule.
* sysdeps/x86_64/dl-machine.h: Include <dl-procinfo.h> and
<cpuid.h>.
(elf_machine_runtime_setup): Use _dl_runtime_resolve_sse,
_dl_runtime_resolve_avx, or _dl_runtime_resolve_avx512,
_dl_runtime_profile_sse, _dl_runtime_profile_avx, or
_dl_runtime_profile_avx512, based on HAS_ARCH_FEATURE.
* sysdeps/x86_64/dl-trampoline.S: Rewrite.
* sysdeps/x86_64/dl-trampoline.h: Likewise.
* sysdeps/x86_64/ifuncmain8.c: New file.
* sysdeps/x86_64/ifuncmod8.c: Likewise.
* sysdeps/x86_64/nptl/tcb-offsets.sym (RTLD_SAVESPACE_SSE):
Removed.
* sysdeps/x86_64/nptl/tls.h (__128bits): Removed.
(tcbhead_t): Change rtld_must_xmm_save to __glibc_unused1.
Change rtld_savespace_sse to __glibc_unused2.
(RTLD_CHECK_FOREIGN_CALL): Removed.
(RTLD_ENABLE_FOREIGN_CALL): Likewise.
(RTLD_PREPARE_FOREIGN_CALL): Likewise.
(RTLD_FINALIZE_FOREIGN_CALL): Likewise.
PowerPC has always used __IPC_64 like most other architectures, which
means that __ASSUME_IPC64 can be always true. Also, all other
architecture implementations that use the ipc syscall are effectively
identical to the generic version and can be removed.
In powerpc64, memchr was always pointing to the internal __GI_memchr
implementation. This patch fixes that and makes it use the
optimized POWER7 version when adequate.
* sysdeps/powerpc/powerpc64/multiarch/memchr-ppc64.c: Make
memchr not point to the internal __GI_memchr implementation.
sysdeps/i386/i686/multiarch/strcasestr-c.c became unused after
commit 1818483b15
Author: Andreas Schwab <schwab@suse.de>
Date: Wed Dec 18 11:53:27 2013 +1000
Remove use of SSE4.2 functions for strstr on i686
which contains
-sysdep_routines += strcspn-c strpbrk-c strspn-c strstr-c strcasestr-c
+sysdep_routines += strcspn-c strpbrk-c strspn-c
sysdeps/x86_64/multiarch/strcasestr.c became useless after
t 584b18eb4d
Author: Ondřej Bílka <neleai@seznam.cz>
Date: Sat Dec 14 19:33:56 2013 +0100
Add strstr with unaligned loads. Fixes bug 12100.
which changes sysdeps/x86_64/multiarch/strcasestr.c to
libc_ifunc (__strcasestr, __strcasestr_sse2);
This patch removes these file.
* i386/i686/multiarch/strcasestr-c.c: Removed.
* x86_64/multiarch/strcasestr.c: Likewise.
* x86_64/multiarch/ifunc-impl-list.c (__libc_ifunc_impl_list):
Remove strcasestr.
Removing the use of -Wno-uninitialized for math/ shows errors for
ldbl-128ibm:
../sysdeps/ieee754/ldbl-128ibm/s_nearbyintl.c: In function '__nearbyintl':
../sysdeps/ieee754/ldbl-128ibm/s_nearbyintl.c:119:34: error: 'low' may be used uninitialized in this function [-Werror=maybe-uninitialized]
u.d[1].d = high - u.d[0].d + low;
^
../sysdeps/ieee754/ldbl-128ibm/s_nearbyintl.c:119:23: error: 'high' may be used uninitialized in this function [-Werror=maybe-uninitialized]
u.d[1].d = high - u.d[0].d + low;
^
These errors are correct: if the high part of the argument is a NaN,
and the low part is nonzero but has absolute value less than 2^52,
those variables can be used uninitialized. This patch rearranges the
code so that the variables are always initialized with the natural
values, and then possibly modified later, to avoid this uninitialized
use. (Note that there are still other issues with this code and NaNs
that are not fixed by this patch.) No bug filed in Bugzilla or
testcase added for the uninitialized use since it wasn't user-visible
with the compiler I tried (that is, I still got a NaN result).
Tested for powerpc.
* sysdeps/ieee754/ldbl-128ibm/s_nearbyintl.c: Always initialize
variables for high and low parts before possibly modifying them.
Move sysdeps/x86_64/multiarch/init-arch.h to sysdeps/x86/init-arch.h
which can be used for both i386 and x86_64.
* sysdeps/i386/i686/multiarch/init-arch.h: Removed.
* sysdeps/unix/sysv/linux/x86/init-arch.h: Likewise.
* sysdeps/x86_64/cacheinfo.c: Include <init-arch.h> instead
of "multiarch/init-arch.h".
* sysdeps/x86_64/multiarch/init-arch.h: Renamed to ...
* sysdeps/x86/init-arch.h: This.
Both files include sysdeps/x86_64/multiarch/init-arch.c which has been
removed.
* sysdeps/i386/i686/multiarch/init-arch.c: Removed.
* sysdeps/unix/sysv/linux/x86/init-arch.c: Likewise.
The csqrt implementations in glibc can miss underflow exceptions when
the real or imaginary part of the result becomes tiny in the course of
scaling down (in particular, multiplication by 0.5) and that scaling
is exact although the relevant part of the mathematical result isn't.
This patch forces the exception in a similar way to previous fixes.
Tested for x86_64 and x86.
[BZ #18370]
* math/s_csqrt.c (__csqrt): Force underflow exception for results
whose real or imaginary part has small absolute value.
* math/s_csqrtf.c (__csqrtf): Likewise.
* math/s_csqrtl.c (__csqrtl): Likewise.
* math/auto-libm-test-in: Add more tests of csqrt.
* math/auto-libm-test-out: Regenerated.
* sysdeps/i386/fpu/libm-test-ulps: Update.
This patch adds extra inline functions to change the Program Priority
Register from ISA 2.07.
2015-08-19 Gabriel F. T. Gomes <gftg@linux.vnet.ibm.com>
* sysdeps/powerpc/sys/platform/ppc.h (__ppc_set_ppr_med_high,
__ppc_set_ppr_very_low): New functions.
* manual/platform.texi: Add documentation about
__ppc_set_ppr_med_high and __ppc_set_ppr_very_low.
Fix the bind-now case when DT_REL and DT_JMPREL sections are separate
and there is a gap between them.
[BZ #14341]
* elf/dynamic-link.h (elf_machine_lazy_rel): Properly handle the
case when there is a gap between DT_REL and DT_JMPREL sections.
* sysdeps/x86_64/Makefile (tests): Add tst-split-dynreloc.
(LDFLAGS-tst-split-dynreloc): New.
(tst-split-dynreloc-ENV): Likewise.
* sysdeps/x86_64/tst-split-dynreloc.c: New file.
* sysdeps/x86_64/tst-split-dynreloc.lds: Likewise.
__xstat_conv, __xstat64_conv and __xstat32_conv are internal to glibc.
They should be marked as hidden so that they can't be called without
PLT.
[BZ #18822]
* sysdeps/unix/sysv/linux/xstatconv.h (__xstat_conv): Add
attribute_hidden.
(__xstat64_conv): Likewise.
(__xstat32_conv): Likewise.
Since _dl_x86_cpu_features is always available, we can use x86-64
cacheinfo.c and sysconf.c for both i386 and x86-64.
* sysdeps/i386/i686/Makefile
[$(subdir) == string] (sysdep_routines): Moved to ...
* sysdeps/i386/Makefile: Here.
* sysdeps/i386/i686/cacheinfo.c: Moved to ...
* sysdeps/i386/cacheinfo.c: Here.
* sysdeps/unix/sysv/linux/i386/sysconf.c: Removed.
* sysdeps/unix/sysv/linux/i386/i686/sysconf.c: Likewise.
* sysdeps/unix/sysv/linux/x86_64/sysconf.c: Moved to ...
* sysdeps/unix/sysv/linux/x86/sysconf.c: Here.
This patch fixes -Wundef warnings relating to __mips_isa_rev being
undefined.
Tested for mips64 (all three ABIs) that there is a clean build and
testsuite run with -Wno-error=undef removed (and my other -Wundef
patches applied).
* sysdeps/mips/dl-machine.h [__mips_isa_rev < 6]: Change
conditionals to [!defined __mips_isa_rev || __mips_isa_rev < 6].
* sysdeps/mips/machine-gmon.h [__mips_isa_rev < 6]: Likewise.
Some features in hwcap.h do not have matching string descriptors
to be displayed when LD_SHOW_AUXV=1. This patch fixes the problem.
2015-08-13 Carlos Eduardo Seo <cseo@linux.vnet.ibm.com>
* sysdeps/powerpc/dl-procinfo.c:
(_dl_powerpc_cap_flags): Added missing strings for some
hwcap features.
* sysdeps/powerpc/dl-procinfo.h: Updated hwcap bit count.
cpuid, i586 and i686 instructions are available if the processor
specified by -march= supports them. We can use this information
to determine whether those instructions can be used safely.
* sysdeps/x86/cpu-features.c (init_cpu_features): Check
whether cpuid is available only if HAS_CPUID is 0.
* sysdeps/x86/cpu-features.h (HAS_CPUID): New.
(HAS_I586): Likewise.
(HAS_I686): Likewise.
This brings hppa inline with all the other arches and main code where we
require TLS support everywhere. That means dropping the defines USE_TLS
and USE___THREAD, and dropping the binutils check (since we already have
a version requirement that is new enough).
Various fma implementations have logic that, when computing fma (x, y,
z) where z is large (so care needs taking to avoid internal overflow)
but x * y is small, scale x * y up instead of down to avoid internal
underflows resulting from scaling down. (In these cases, x * y is
small enough that only its sign actually matters rather than the exact
value.)
The threshold for scaling up instead of down was correct for "if the
unscaled values were multiplied, the low part of the multiplication
could underflow", and the scaling was sufficient to ensure that the
low part of the multiplication did not underflow (given that cases of
very small x * y - less than half the least subnormal - were
previously dealt with). However, the choice in the functions wasn't
between scaling up or no scaling, but between scaling up and scaling
down (scaling down actually being needed when x * y isn't so small
compared to z and so the exact value does matter). Thus a larger
threshold is needed to ensure that scaling down doesn't produce values
the multiplication of whose low parts underflows. This patch
increases the thresholds accordingly.
Tested for x86_64, x86 and mips64 (with the MIPS version of s_fmal.c
removed so that the ldbl-128 version gets tested instead of the
soft-fp one).
[BZ #18824]
* sysdeps/ieee754/dbl-64/s_fma.c (__fma): Increase threshold for
scaling x * y up instead of down.
* sysdeps/ieee754/ldbl-128/s_fmal.c (__fmal): Likewise.
* sysdeps/ieee754/ldbl-96/s_fmal.c (__fmal): Likewise.
* math/auto-libm-test-in: Add more tests of fma.
* math/auto-libm-test-out: Regenerated.
The change in 0b5395f052 replaced calls
to __get_cpu_features@plt followed by a mov from rax to rdx, with a
single macro LOAD_RTLD_GLOBAL_RO_RDX. It is pretty clear that there
was a typo in s_floorf and __nearbyint due to which the (now incorrect)
mov was not removed. This patch removes that mov.
* sysdeps/x86_64/fpu/multiarch/s_floorf.S (__floorf): Remove
unnecessary movq.
* sysdeps/x86_64/fpu/multiarch/s_nearbyint.S (__nearbyint):
Likewise.
This patch adds more test inputs to various libm functions found
through random generation to have larger ulps errors than previously
listed in libm-test-ulp, on at least one of x86_64 and x86.
Tested for x86_64 and x86.
* math/auto-libm-test-in: Add more tests of acos, acosh, asin,
asinh, atan, atan2, atanh, cabs, cbrt, cosh, csqrt, erf, erfc,
exp, exp2, lgamma, log, log1p, log2, pow, sin, sincos, tan, tanh
and tgamma.
* math/auto-libm-test-out: Regenerated.
* sysdeps/i386/fpu/libm-test-ulps: Update.
* sysdeps/x86_64/fpu/libm-test-ulps: Likewise.
Similar to various other bugs in this area, some tanh implementations
do not raise the underflow exception for subnormal arguments, when the
result is tiny and inexact. This patch forces the exception in a
similar way to previous fixes.
Tested for x86_64, x86, mips64 and powerpc.
[BZ #16520]
* sysdeps/ieee754/dbl-64/s_tanh.c: Include <float.h>.
(__tanh): Force underflow exception for arguments with small
absolute value.
* sysdeps/ieee754/flt-32/s_tanhf.c: Include <float.h>.
(__tanhf): Force underflow exception for arguments with small
absolute value.
* sysdeps/ieee754/ldbl-128/s_tanhl.c: Include <float.h>.
(__tanhl): Force underflow exception for arguments with small
absolute value.
* sysdeps/ieee754/ldbl-128ibm/s_tanhl.c: Include <float.h>.
(__tanhl): Force underflow exception for arguments with small
absolute value.
* sysdeps/ieee754/ldbl-96/s_tanhl.c: Include <float.h>.
(__tanhl): Force underflow exception for arguments with small
absolute value.
* math/auto-libm-test-in: Add more tests of tanh.
* math/auto-libm-test-out: Regenerated.
* sysdeps/i386/fpu/libm-test-ulps: Update.
Since not all i486 processors support cpuid, we call __get_cpuid_max to
check if cpuid is available before using it if not compiling for i586,
i686 nor x86-64.
* sysdeps/x86/cpu-features.c (init_cpu_features): Call
__get_cpuid_max if not compiling for i586, i686 nor x86-64.
This patch updates x86 elision-conf.c to use the newly defined
HAS_CPU_FEATURE from <cpu-features.h>.
* sysdeps/unix/sysv/linux/x86/elision-conf.c (elision_init):
Replace HAS_RTM with HAS_CPU_FEATURE (RTM).
