In non-default rounding modes, tgamma can be slightly less accurate
than permitted by glibc's accuracy goals.
Part of the problem is error accumulation, addressed in this patch by
setting round-to-nearest for internal computations. However, there
was also a bug in the code dealing with computing pow (x + n, x + n)
where x + n is not exactly representable, providing another source of
error even in round-to-nearest mode; it was necessary to address both
bugs to get errors for all testcases within glibc's accuracy goals.
Given this second fix, accuracy in round-to-nearest mode is also
improved (hence regeneration of ulps for tgamma should be from scratch
- truncate libm-test-ulps or at least remove existing tgamma entries -
so that the expected ulps can be reduced).
Some additional complications also arose. Certain tgamma tests should
strictly, according to IEEE semantics, overflow or not depending on
the rounding mode; this is beyond the scope of glibc's accuracy goals
for any function without exactly-determined results, but
gen-auto-libm-tests doesn't handle being lax there as it does for
underflow. (libm-test.inc also doesn't handle being lax about whether
the result in cases very close to the overflow threshold is infinity
or a finite value close to overflow, but that doesn't cause problems
in this case though I've seen it cause problems with random test
generation for some functions.) Thus, spurious-overflow markings,
with a comment, are added to auto-libm-test-in (no bug in Bugzilla
because the issue is with the testsuite, not a user-visible bug in
glibc). And on x86, after the patch I saw ERANGE issues as previously
reported by Carlos (see my commentary in
<https://sourceware.org/ml/libc-alpha/2015-01/msg00485.html>), which
needed addressing by ensuring excess range and precision were
eliminated at various points if FLT_EVAL_METHOD != 0.
I also noticed and fixed a cosmetic issue where 1.0f was used in long
double functions and should have been 1.0L.
This completes the move of all functions to testing in all rounding
modes with ALL_RM_TEST, so gen-libm-have-vector-test.sh is updated to
remove the workaround for some functions not using ALL_RM_TEST.
Tested for x86_64, x86, mips64 and powerpc.
[BZ #18613]
* sysdeps/ieee754/dbl-64/e_gamma_r.c (gamma_positive): Take log of
X_ADJ not X when adjusting exponent.
(__ieee754_gamma_r): Do intermediate computations in
round-to-nearest then adjust overflowing and underflowing results
as needed.
* sysdeps/ieee754/flt-32/e_gammaf_r.c (gammaf_positive): Take log
of X_ADJ not X when adjusting exponent.
(__ieee754_gammaf_r): Do intermediate computations in
round-to-nearest then adjust overflowing and underflowing results
as needed.
* sysdeps/ieee754/ldbl-128/e_gammal_r.c (gammal_positive): Take
log of X_ADJ not X when adjusting exponent.
(__ieee754_gammal_r): Do intermediate computations in
round-to-nearest then adjust overflowing and underflowing results
as needed. Use 1.0L not 1.0f as numerator of division.
* sysdeps/ieee754/ldbl-128ibm/e_gammal_r.c (gammal_positive): Take
log of X_ADJ not X when adjusting exponent.
(__ieee754_gammal_r): Do intermediate computations in
round-to-nearest then adjust overflowing and underflowing results
as needed. Use 1.0L not 1.0f as numerator of division.
* sysdeps/ieee754/ldbl-96/e_gammal_r.c (gammal_positive): Take log
of X_ADJ not X when adjusting exponent.
(__ieee754_gammal_r): Do intermediate computations in
round-to-nearest then adjust overflowing and underflowing results
as needed. Use 1.0L not 1.0f as numerator of division.
* math/libm-test.inc (tgamma_test_data): Remove one test. Moved
to auto-libm-test-in.
(tgamma_test): Use ALL_RM_TEST.
* math/auto-libm-test-in: Add one test of tgamma. Mark some other
tests of tgamma with spurious-overflow.
* math/auto-libm-test-out: Regenerated.
* math/gen-libm-have-vector-test.sh: Do not check for START.
* sysdeps/i386/fpu/libm-test-ulps: Update.
* sysdeps/x86_64/fpu/libm-test-ulps: Likewise.
The ldbl-128 implementation of j1l produces spurious underflow
exceptions for some small arguments, as a result of squaring the
argument. This patch fixes it just to use a linear approximation for
sufficiently small arguments, and then to force an underflow exception
only in the cases where it is required.
Tested for mips64.
[BZ #18612]
* sysdeps/ieee754/ldbl-128/e_j1l.c (__ieee754_j1l): For small
arguments, just return 0.5 times the argument, with underflow
forced as needed.
* math/auto-libm-test-in: Add more tests of j1.
* math/auto-libm-test-out: Regenerated.
Similar to various other bugs in this area, j1 and jn implementations
can fail to raise the underflow exception when the internal
computation is exact although the actual function is inexact. This
patch forces the exception in a similar way to other such fixes. (The
ldbl-128 / ldbl-128ibm j1l implementation is different and doesn't
need a change for this until spurious underflows in it are fixed.)
Tested for x86_64, x86, mips64 and powerpc.
[BZ #16559]
* sysdeps/ieee754/dbl-64/e_j1.c: Include <float.h>.
(__ieee754_j1): Force underflow exception for small results.
* sysdeps/ieee754/dbl-64/e_jn.c (__ieee754_jn): Likewise.
* sysdeps/ieee754/flt-32/e_j1f.c: Include <float.h>.
(__ieee754_j1f): Force underflow exception for small results.
* sysdeps/ieee754/flt-32/e_jnf.c (__ieee754_jnf): Likewise.
* sysdeps/ieee754/ldbl-128/e_jnl.c (__ieee754_jnl): Likewise.
* sysdeps/ieee754/ldbl-128ibm/e_jnl.c (__ieee754_jnl): Likewise.
* sysdeps/ieee754/ldbl-96/e_j1l.c: Include <float.h>.
(__ieee754_j1l): Force underflow exception for small results.
* sysdeps/ieee754/ldbl-96/e_jnl.c (__ieee754_jnl): Likewise.
* math/auto-libm-test-in: Add more tests of j1 and jn.
* math/auto-libm-test-out: Regenerated.
This patch updates installed glibc headers for new definitions from
Linux 4.0 and 4.1 that seem relevant to glibc headers. In addition, I
noticed that PF_IB / AF_IB, added in Linux 3.11, were missing for no
obvious reason, so added those as well.
Tested for x86_64 (testsuite, and that installed stripped shared
libraries are unchanged by the patch).
* sysdeps/unix/sysv/linux/bits/in.h (IP_CHECKSUM): New macro.
* sysdeps/unix/sysv/linux/bits/socket.h (PF_IB): Likewise.
(PF_MPLS): Likewise.
(AF_IB): Likewise.
(AF_MPLS): Likewise.
* sysdeps/unix/sysv/linux/sys/mount.h (MS_LAZYTIME): New enum
value and macro.
(MS_RMT_MASK): Include MS_LAZYTIME.
This tag allows debugging of MIPS position independent executables
and provides access to shared library information.
* elf/elf.h (DT_MIPS_RLD_MAP_REL): New macro.
(DT_MIPS_NUM): Update.
* sysdeps/mips/dl-machine.h (ELF_MACHINE_DEBUG_SETUP): Handle
DT_MIPS_RLD_MAP_REL.
Some existing jn tests, if run in non-default rounding modes, produce
errors above those accepted in glibc, which causes problems for moving
tests of jn to use ALL_RM_TEST. This patch makes jn set rounding
to-nearest internally, as was done for yn some time ago, then computes
the appropriate underflowing value for results that underflowed to
zero in to-nearest, and moves the tests to ALL_RM_TEST. It does
nothing about the general inaccuracy of Bessel function
implementations in glibc, though it should make jn more accurate on
average in non-default rounding modes through reduced error
accumulation. The recomputation of results that underflowed to zero
should as a side-effect fix some cases of bug 16559, where jn just
used an exact zero, but that is *not* the goal of this patch and other
cases of that bug remain unfixed.
(Most of the changes in the patch are reindentation to add new scopes
for SET_RESTORE_ROUND*.)
Tested for x86_64, x86, powerpc and mips64.
[BZ #16559]
[BZ #18602]
* sysdeps/ieee754/dbl-64/e_jn.c (__ieee754_jn): Set
round-to-nearest internally then recompute results that
underflowed to zero in the original rounding mode.
* sysdeps/ieee754/flt-32/e_jnf.c (__ieee754_jnf): Likewise.
* sysdeps/ieee754/ldbl-128/e_jnl.c (__ieee754_jnl): Likewise.
* sysdeps/ieee754/ldbl-128ibm/e_jnl.c (__ieee754_jnl): Likewise.
* sysdeps/ieee754/ldbl-96/e_jnl.c (__ieee754_jnl): Likewise
* math/libm-test.inc (jn_test): Use ALL_RM_TEST.
* sysdeps/i386/fpu/libm-test-ulps: Update.
* sysdeps/x86_64/fpu/libm-test-ulps: Likewise.
cexp, ccos, ccosh, csin and csinh have spurious underflows in cases
where they compute sin of the smallest normal, that produces an
underflow exception (depending on which sin implementation is in use)
but the final result does not underflow. ctan and ctanh may also have
such underflows, or they may be latent (the issue there is that
e.g. ctan (DBL_MIN) should, rounded upwards, be the next double value
above DBL_MIN, which under glibc's accuracy goals may not have an
underflow exception, but the intermediate computation of sin (DBL_MIN)
would legitimately underflow on before-rounding architectures).
This patch fixes all those functions so they use plain comparisons (>
DBL_MIN etc.) instead of comparing the result of fpclassify with
FP_SUBNORMAL (in all these cases, we already know the number being
compared is finite). Note that in the case of csin / csinf / csinl,
there is no need for fabs calls in the comparison because the real
part has already been reduced to its absolute value.
As the patch fixes the failures that previously obstructed moving
tests of cexp to use ALL_RM_TEST, those tests are moved to ALL_RM_TEST
by the patch (two functions remain yet to be converted).
Tested for x86_64 and x86 and ulps updated accordingly.
[BZ #18594]
* math/s_ccosh.c (__ccosh): Compare with least normal value
instead of comparing class with FP_SUBNORMAL.
* math/s_ccoshf.c (__ccoshf): Likewise.
* math/s_ccoshl.c (__ccoshl): Likewise.
* math/s_cexp.c (__cexp): Likewise.
* math/s_cexpf.c (__cexpf): Likewise.
* math/s_cexpl.c (__cexpl): Likewise.
* math/s_csin.c (__csin): Likewise.
* math/s_csinf.c (__csinf): Likewise.
* math/s_csinh.c (__csinh): Likewise.
* math/s_csinhf.c (__csinhf): Likewise.
* math/s_csinhl.c (__csinhl): Likewise.
* math/s_csinl.c (__csinl): Likewise.
* math/s_ctan.c (__ctan): Likewise.
* math/s_ctanf.c (__ctanf): Likewise.
* math/s_ctanh.c (__ctanh): Likewise.
* math/s_ctanhf.c (__ctanhf): Likewise.
* math/s_ctanhl.c (__ctanhl): Likewise.
* math/s_ctanl.c (__ctanl): Likewise.
* math/auto-libm-test-in: Add more tests of ccos, ccosh, cexp,
csin, csinh, ctan and ctanh.
* math/auto-libm-test-out: Regenerated.
* math/libm-test.inc (cexp_test): Use ALL_RM_TEST.
* sysdeps/i386/fpu/libm-test-ulps: Update.
* sysdeps/x86_64/fpu/libm-test-ulps: Likewise.
csin and csinh can produce bad results when overflowing in directed
rounding modes, because a multiplication that can overflow is followed
by a possible negation. This patch fixes this by negating one of the
arguments of the multiplication before the multiplication instead of
negating the result.
The new tests for this issue are added to auto-libm-test-in, starting
use of that file for csin and csinh. The issue was found in the
course of moving existing tests for csin and csinh (existing tests, by
being enabled in more cases than previously, showed the issue for
float and double but not for long double); that move will now be done
separately.
Tested for x86_64 and x86 and ulps updated accordingly.
[BZ #18593]
* math/s_csin.c (__csin): Negate before rather than after possibly
overflowing multiplication.
* math/s_csinf.c (__csinf): Likewise.
* math/s_csinh.c (__csinh): Likewise.
* math/s_csinhf.c (__csinhf): Likewise.
* math/s_csinhl.c (__csinhl): Likewise.
* math/s_csinl.c (__csinl): Likewise.
* math/auto-libm-test-in: Add some tests of csin and csinh.
* math/auto-libm-test-out: Regenerated.
* math/libm-test.inc (csin_test_data): Use AUTO_TESTS_c_c.
(csinh_test_data): Likewise.
* sysdeps/x86_64/fpu/libm-test-ulps: Update.
Similar to various other bugs in this area, the ldbl-128 expl
implementation does not raise the underflow exception for all
subnormal results, if the scaling down is exact although the actual
result is inexact. This patch fixes this by forcing the exception in
this case (the tests that failed before and pass after the test are
already in the testsuite).
Tested for mips64.
[BZ #18586]
* sysdeps/ieee754/ldbl-128/e_expl.c (__ieee754_expl): Force
underflow exception for small results.
Similar to various other bugs in this area, some sin and sincos
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 #16526]
[BZ #16538]
* sysdeps/ieee754/dbl-64/s_sin.c: Include <float.h>.
(__sin): Force underflow exception for arguments with small
absolute value.
* sysdeps/ieee754/flt-32/k_sinf.c: Include <float.h>.
(__kernel_sinf): Force underflow exception for arguments with
small absolute value.
* sysdeps/ieee754/ldbl-128/k_sincosl.c: Include <float.h>.
(__kernel_sincosl): Force underflow exception for arguments with
small absolute value.
* sysdeps/ieee754/ldbl-128/k_sinl.c: Include <float.h>.
(__kernel_sinl): Force underflow exception for arguments with
small absolute value.
* sysdeps/ieee754/ldbl-128ibm/k_sincosl.c: Include <float.h>.
(__kernel_sincosl): Force underflow exception for arguments with
small absolute value.
* sysdeps/ieee754/ldbl-128ibm/k_sinl.c: Include <float.h>.
(__kernel_sinl): Force underflow exception for arguments with
small absolute value.
* sysdeps/ieee754/ldbl-96/k_sinl.c: Include <float.h>.
(__kernel_sinl): Force underflow exception for arguments with
small absolute value.
* sysdeps/powerpc/fpu/k_sinf.c: Include <float.h>.
(__kernel_sinf): Force underflow exception for arguments with
small absolute value.
* math/auto-libm-test-in: Add more tests of sin and sincos.
* math/auto-libm-test-out: Regenerated.
__kernel_standard_l converts long double arguments to double for use
in SVID "struct exception". This has special-case handling for when
that conversion would overflow or underflow but the original long
double function wouldn't. However, it turns out that "inexact"
exceptions can be spurious here as well, when the function is exactly
determined and __kernel_standard_l is being called for a domain error.
This patch fixes this by using feholdexcept / fesetenv to avoid
exceptions from the conversion, replacing the previous special-case
logic for overflow and underflow (this covers all functions using
__kernel_standard_l, not just those that actually need a change, since
there doesn't seem to be much point in restricting things just to the
functions that mustn't get "inexact" here).
Tested for x86_64 and x86.
[BZ #18245]
[BZ #18583]
* sysdeps/ieee754/k_standardl.c: Include <fenv.h>.
(__kernel_standard_l): Use feholdexcept and fesetenv around
conversion to double instead of special-casing overflow and
underflow.
* math/libm-test.inc (fmod_test_data): Add more tests.
(remainder_test_data): Likewise.
(sqrt_test_data): Likewise.
This fixes BZ #17403 by defining atomic_full_barrier,
atomic_read_barrier, and atomic_write_barrier on x86 and x86_64. A full
barrier is implemented through an atomic idempotent modification to the
stack and not through using mfence because the latter can supposedly be
somewhat slower due to having to provide stronger guarantees wrt.
self-modifying code, for example.
The csqrt implementations in glibc can cause spurious underflows in
some cases as a side-effect of the scaling for large arguments (when
underflow is correct for the square root of the argument that was
scaled down to avoid overflow, but not for the original argument).
This patch arranges to avoid the underflowing intermediate computation
(eliminating a multiplication in 0.5 in the problem cases where a
subsequent scaling by 2 would follow).
Tested for x86_64 and x86 and ulps updated accordingly (only needed
for x86).
[BZ #18371]
* math/s_csqrt.c (__csqrt): Avoid multiplication by 0.5 where
intermediate but not final result might underflow.
* 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.
The dbl-64 and flt-32 implementations of exp2 functions produce
spurious underflow exceptions. The underlying reason is the same in
both cases: the computation works as (2^a - 1)*2^b + 2^b for suitably
chosen a and b, where a has small magnitude so 2^a - 1 can be computed
with a low-degree polynomial approximation, and (2^a - 1)*2^b can
underflow even when the final result does not. This patch fixes this
by adjusting the threshold for when scaling is used to avoid
intermediate underflow so it works for any possible value of a where
the final result would not underflow.
Tested for x86_64 and x86.
[BZ #18219]
* sysdeps/ieee754/dbl-64/e_exp2.c (__ieee754_exp2): Reduce
threshold on absolute value of exponent for which scaling is used.
* sysdeps/ieee754/flt-32/e_exp2f.c (__ieee754_exp2f): Likewise.
* math/auto-libm-test-in: Add more tests of exp2.
* math/auto-libm-test-out: Regenerated.
Similar to various other bugs in this area, some expm1 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.
(The issue does not apply to the ldbl-* implementations or to those
for x86 / x86_64 long double. The change to
sysdeps/ieee754/dbl-64/wordsize-64/e_cosh.c is one I missed when
previously fixing bug 16354; the bug in that implementation was
previously latent, but the expm1 fixes stopped it being latent and so
required it to be fixed to avoid spurious underflows from cosh.)
Tested for x86_64 and x86.
[BZ #16353]
* sysdeps/i386/fpu/s_expm1.S (dbl_min): New object.
(__expm1): Force underflow exception for arguments with small
absolute value.
* sysdeps/i386/fpu/s_expm1f.S (flt_min): New object.
(__expm1f): Force underflow exception for arguments with small
absolute value.
* sysdeps/ieee754/dbl-64/s_expm1.c: Include <float.h>.
(__expm1): Force underflow exception for arguments with small
absolute value.
* sysdeps/ieee754/flt-32/s_expm1f.c: Include <float.h>.
(__expm1f): Force underflow exception for arguments with small
absolute value.
* sysdeps/ieee754/dbl-64/wordsize-64/e_cosh.c (__ieee754_cosh):
Check for small arguments before calling __expm1.
* math/auto-libm-test-in: Do not mark underflow exceptions as
possibly missing for bug 16353.
* math/auto-libm-test-out: Regenerated.
In the x86 / x86_64 implementations of expm1l, when expm1l's result
should underflow to 0 (argument minus the least subnormal, in some
rounding modes), it can be a zero of the wrong sign. This patch fixes
this by returning the argument with underflow forced in that case
(this is a 1ulp error relative to the correctly rounded result of -0,
which is OK in terms of the documented accuracy goals, whereas a
result with the wrong sign never is).
Tested for x86_64 and x86.
[BZ #18569]
* sysdeps/i386/fpu/e_expl.S (IEEE754_EXPL) [USE_AS_EXPM1L]: Force
underflow and return argument in case of subnormal argument.
* sysdeps/x86_64/fpu/e_expl.S (IEEE754_EXPL) [USE_AS_EXPM1L]:
Likewise.
* math/auto-libm-test-in: Add more tests of expm1.
* math/auto-libm-test-out: Regenerated.
Similar to various other bugs in this area, the x86 and x86_64
implementations of expl / exp10l can fail to produce underflow
exceptions when the unscaled result has trailing 0 bits so the scaling
down to subnormal precision is exact. This patch fixes this by
forcing the exception in the case of tiny results.
Tested for x86_64 and x86.
[BZ #16361]
* sysdeps/i386/fpu/e_expl.S [!USE_AS_EXPM1L] (cmin): New object.
[!USE_AS_EXPM1L] (IEEE754_EXPL): Force underflow exception for
tiny results.
* sysdeps/x86_64/fpu/e_expl.S [!USE_AS_EXPM1L] (cmin): New object.
[!USE_AS_EXPM1L] (IEEE754_EXPL): Force underflow exception for
tiny results.
* math/auto-libm-test-in: Add more tests of exp and exp10. Do not
mark underflow exceptions as possibly missing for bug 16361.
* math/auto-libm-test-out: Regenerated.
Similar to various other bugs in this area, some asinh 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 and mips64.
[BZ #16350]
* sysdeps/i386/fpu/s_asinh.S (__asinh): Force underflow exception
for arguments with small absolute value.
* sysdeps/i386/fpu/s_asinhf.S (__asinhf): Likewise.
* sysdeps/i386/fpu/s_asinhl.S (__asinhl): Likewise.
* sysdeps/ieee754/dbl-64/s_asinh.c: Include <float.h>.
(__asinh): Force underflow exception for arguments with small
absolute value.
* sysdeps/ieee754/flt-32/s_asinhf.c: Include <float.h>.
(__asinhf): Force underflow exception for arguments with small
absolute value.
* sysdeps/ieee754/ldbl-128/s_asinhl.c: Include <float.h>.
(__asinhl): Force underflow exception for arguments with small
absolute value.
* sysdeps/ieee754/ldbl-128ibm/s_asinhl.c: Include <float.h>.
(__asinhl): Force underflow exception for arguments with small
absolute value.
* sysdeps/ieee754/ldbl-96/s_asinhl.c: Include <float.h>.
(__asinhl): Force underflow exception for arguments with small
absolute value.
* math/auto-libm-test-in: Do not mark underflow exceptions as
possibly missing for bug 16350.
* math/auto-libm-test-out: Regenerated.
sysdeps/unix/sysv/linux/bits/in.h (as included in netinet/in.h, and
via that in netdb.h and arpa/inet.h) defines a series of MCAST_*
macros, both under __USE_MISC and then again unconditionally. These
are not POSIX macros, nor in any of the namespaces listed in POSIX as
reserved for this header, so should not be defined unconditionally.
This patch duly removes the unconditional definitions, leaving the
ones conditional on __USE_MISC.
Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by the patch).
[BZ #18558]
* sysdeps/unix/sysv/linux/bits/in.h (MCAST_JOIN_GROUP): Remove
unconditional definition.
(MCAST_BLOCK_SOURCE): Likewise.
(MCAST_UNBLOCK_SOURCE): Likewise.
(MCAST_LEAVE_GROUP): Likewise.
(MCAST_JOIN_SOURCE_GROUP): Likewise.
(MCAST_LEAVE_SOURCE_GROUP): Likewise.
(MCAST_MSFILTER): Likewise.
* conform/Makefile (test-xfail-XOPEN2K/arpa/inet.h/conform):
Remove variable.
(test-xfail-XOPEN2K/netdb.h/conform): Likewise.
(test-xfail-XOPEN2K/netinet/in.h/conform): Likewise.
(test-xfail-XOPEN2K8/arpa/inet.h/conform): Likewise.
(test-xfail-XOPEN2K8/netdb.h/conform): Likewise.
(test-xfail-XOPEN2K8/netinet/in.h/conform): Likewise.
sysdeps/ieee754/ldbl-128ibm has its own versions of cprojl, ctanhl and
ctanl.
Having its own versions, where otherwise the math/ copies are
generally used for all floating-point formats, means they are liable
to get out of sync and not benefit from bug fixes to the generic
versions. The substantive differences (not arising from getting out
of sync and slightly different fixes for the same issues) are: long
double compat handling (also done in the ldbl-opt versions, so doesn't
require special versions for ldbl-128ibm); handling of LDBL_EPSILON
(conditionally undefined and redefined in other math/ implementations,
so doesn't justify a special version), and:
/* __gcc_qmul does not respect -0.0 so we need the following fixup. */
if ((__real__ res == 0.0L) && (__real__ x == 0.0L))
__real__ res = __real__ x;
if ((__real__ res == 0.0L) && (__imag__ x == 0.0L))
__imag__ res = __imag__ x;
But if that statement about __gcc_qmul was ever true for an old
version of that libgcc function, it's not the case for any GCC version
now supported to build glibc; there's explicit logic early in that
function (and similarly in __gcc_qdiv) to return an appropriately
signed zero if the product of the high parts is zero. So this patch
adds the special LDBL_EPSILON handling to the generic functions and
removes the ldbl-128ibm versions.
Tested for powerpc32 (compared test-ldouble.out before and after the
changes; there are slight changes to results for ctanl / ctanhl,
arising from divergence of the implementations, but nothing that
affects the overall nature of the issues shown by the testsuite, and
in particular nothing related to signs of zero resutls).
* math/s_ctanhl.c [LDBL_MANT_DIG == 106] (LDBL_EPSILON): Undefine
and redefine.
* math/s_ctanl.c [LDBL_MANT_DIG == 106] (LDBL_EPSILON): Undefine
and redefine.
* sysdeps/ieee754/ldbl-128ibm/s_cprojl.c: Remove file.
* sysdeps/ieee754/ldbl-128ibm/s_ctanhl.c: Likewise.
* sysdeps/ieee754/ldbl-128ibm/s_ctanl.c: Likewise.
nice (XPG3) calls getpriority and setpriority (in XPG4 but not XPG3,
i.e. UX-shaded in XPG4). This patch fixes this by making those
functions into weak aliases of __* functions and calling the __*
versions as needed.
Tested for x86_64 and x86 (testsuite, and that disassembly of
installed shared libraries is unchanged by this patch).
This completes cleaning up the unsorted linknamespace test XFAILs.
[BZ #18553]
* resource/getpriority.c (getpriority): Rename to __getpriority
and define as weak alias of __getpriority.
* resource/setpriority.c (setpriority): Rename to __setpriority
and define as weak alias of __setpriority.
* sysdeps/mach/hurd/getpriority.c (getpriority): Rename to
__getpriority and define as weak alias of __getpriority.
* sysdeps/mach/hurd/setpriority.c (setpriority): Rename to
__setpriority and define as weak alias of __setpriority.
* sysdeps/unix/syscalls.list (getpriority): Use __getpriority as
strong name.
(setpriority): Use __setpriority as strong name.
* sysdeps/unix/sysv/linux/getpriority.c (getpriority): Rename to
__getpriority and define as weak alias of __getpriority.
* include/sys/resource.h (__getpriority): Declare. Use
libc_hidden_proto.
(__setpriority): Likewise.
(getpriority): Don't use libc_hidden_proto.
(setpriority): Likewise.
* sysdeps/posix/nice.c (nice): Call __getpriority instead of
getpriority. Call __setpriority instead of setpriority.
* conform/Makefile (test-xfail-XPG3/unistd.h/linknamespace):
Remove variable.
mq_notify (in the 1996 edition of POSIX) brings in references to recv
and socket (not in POSIX until the 2001 edition). This patch fixes
this by using __recv and __socket, exporting them from libc at version
GLIBC_PRIVATE.
Tested for x86_64 and x86 (testsuite and comparison of installed
stripped shared libraries; PLT / dynamic symbol table changes render
the comparison not particularly useful for libc).
[BZ #18546]
* socket/recv.c (__recv): Use libc_hidden_def.
* socket/socket.c (__socket): Likewise.
* sysdeps/mach/hurd/recv.c (__recv): Likewise.
* sysdeps/mach/hurd/socket.c (__socket): Likewise.
* sysdeps/unix/sysv/linux/generic/recv.c (__recv): Likewise.
* sysdeps/unix/sysv/linux/recv.c (__recv): Use libc_hidden_weak.
* sysdeps/unix/sysv/linux/socket.c (__socket): Use
libc_hidden_def.
* sysdeps/unix/sysv/linux/x86_64/recv.c (__recv): Use
libc_hidden_weak.
* include/sys/socket.h (__socket): Do not use attribute_hidden.
Use libc_hidden_proto.
(__recv): Likewise.
* socket/Versions (libc): Export __recv and __socket at version
GLIBC_PRIVATE.
* sysdeps/unix/sysv/linux/mq_notify.c (helper_thread): Call __recv
instead of recv.
(init_mq_netlink): Call __socket instead of socket.
* conform/Makefile (test-xfail-POSIX/mqueue.h/linknamespace):
Remove variable.
mq_receive calls mq_timedreceive, and mq_send calls mq_timedsend. But
mq_receive and mq_send were in POSIX by 1996, while mq_timed* were
added in the 2001 edition of POSIX. This patch fixes this by making
mq_timed* into weak aliases for __mq_timed* and calling the
__mq_timed* names.
Tested for x86_64 and x86 (testsuite, and that disassembly of
installed shared libraries is unchanged by the patch).
[BZ #18545]
* rt/mq_timedreceive.c (mq_timedreceive): Rename to
__mq_timedreceive and define as alias of __mq_timedreceive. Use
hidden_weak.
* rt/mq_timedsend.c (mq_timedsend): Rename to __mq_timedsend and
define as alias of __mq_timedsend. Use hidden_weak.
* sysdeps/unix/sysv/linux/syscalls.list (mq_timedsend): Use
__mq_timedsend as strong name.
(mq_timedreceive): Use __mq_timedreceive as strong name.
* include/mqueue.h (__mq_timedsend): Declare. Use hidden_proto.
(__mq_timedreceive): Likewise.
* sysdeps/unix/sysv/linux/mq_receive.c (mq_receive): Call
__mq_timedreceive instead of mq_timedreceive.
* sysdeps/unix/sysv/linux/mq_send.c (mq_send): Call __mq_timedsend
instead of mq_timedsend.
* conform/Makefile (test-xfail-UNIX98/mqueue.h/linknamespace):
Remove variable.
The syscall wrappers mechanism automatically creates hidden aliases
for syscalls with libc_hidden_def / libc_hidden_weak. The use of
libc_hidden_* has the side-effect that for syscall wrappers in
non-libc libraries those aliases are not created. In turn, this means
that three mq_* syscalls in sysdeps/unix/sysv/linux/syscalls.list list
the __GI_* names explicitly.
The use of libc_hidden_* dates back to the original introduction of
that support in
2002-08-03 Roland McGrath <roland@redhat.com>
* sysdeps/unix/make-syscalls.sh: Generate libc_hidden_def or
libc_hidden_weak for every system call symbol defined.
(predating the non-libc syscalls in question) and I see no reason for
excluding non-libc syscalls. This patch changes the code to use
hidden_def / hidden_weak (via a wrapper syscall_hidden_def in the case
where the argument is itself a macro, so that the argument gets
expanded before concatenation with __GI_), so avoiding the need to
specify the hidden aliases explicitly in this case.
Tested for x86_64 and x86 (testsuite, and that disassembly of
installed stripped shared libraries is unchanged by the patch; the
mq_* symbols change from weak to strong, which is of no significance
and two of them will shortly change back to weak as part of a fix for
bug 18545).
* sysdeps/unix/make-syscalls.sh (emit_weak_aliases): Use
hidden_def and hidden_weak instead of libc_hidden_def and
libc_hidden_weak.
(top level): Refer to hidden_def in comment.
* sysdeps/unix/syscall-template.S (syscall_hidden_def): New
macro. Use it instead of libc_hidden_def.
* sysdeps/unix/sysv/linux/syscalls.list (mq_timedsend): Do not
specify __GI_* name explicitly.
(mq_timedreceive): Likewise.
(mq_setattr): Likewise.
mq_notify (present in POSIX by 1996) brings in references to
pthread_barrier_init and pthread_barrier_wait (new in the 2001 edition
of POSIX). This patch fixes this by making those functions into weak
aliases of __pthread_barrier_*, exporting the __pthread_barrier_*
names at version GLIBC_PRIVATE and using them in mq_notify.
Tested for x86_64 and x86 (testsuite, and comparison of installed
stripped shared libraries). Changes in addresses from dynamic symbol
table / PLT changes render most comparisons not particularly useful,
but when the addresses of subsequent code don't change there's no sign
of unexpected changes there. This patch does not remove any
linknamespace XFAILs because of other namespace issues remaining with
mqueue.h functions.
[BZ #18544]
* nptl/pthread_barrier_init.c (pthread_barrier_init): Rename to
__pthread_barrier_init and define as weak alias of
__pthread_barrier_init.
* sysdeps/sparc/nptl/pthread_barrier_init.c
(pthread_barrier_init): Likewise.
* nptl/pthread_barrier_wait.c (pthread_barrier_wait): Rename to
__pthread_barrier_wait and define as weak alias of
__pthread_barrier_wait.
* sysdeps/sparc/nptl/pthread_barrier_wait.c
(pthread_barrier_wait): Likewise.
* sysdeps/sparc/sparc32/pthread_barrier_wait.c
(pthread_barrier_wait): Likewise.
* sysdeps/unix/sysv/linux/i386/i486/pthread_barrier_wait.S
(pthread_barrier_wait): Likewise.
* sysdeps/unix/sysv/linux/x86_64/pthread_barrier_wait.S
(pthread_barrier_wait): Likewise.
* nptl/Versions (libpthread): Export __pthread_barrier_init and
__pthread_barrier_wait at version GLIBC_PRIVATE.
* include/pthread.h (__pthread_barrier_init): Declare.
(__pthread_barrier_wait): Likewise.
* sysdeps/unix/sysv/linux/mq_notify.c (notification_function):
Call __pthread_barrier_wait instead of pthread_barrier_wait.
(helper_thread): Likewise.
(init_mq_netlink): Call __pthread_barrier_init instead of
pthread_barrier_init.
The sem_* functions bring in references to tdelete, tfind, tsearch and
twalk. But the t* functions are XSI-shaded, while sem_* aren't. This
patch fixes this by using __t* instead, exporting those functions from
libc at version GLIBC_PRIVATE (since sem_* are in libpthread) and
using libc_hidden_* for the benefit of calls within libc.
Tested for x86_64 and x86 (testsuite, and comparison of disassembly of
installed stripped shared libraries). libpthread gets changes from
PLT reordering; addresses in libc change because of PLT / dynamic
symbol table changes.
[BZ #18536]
* misc/tsearch.c (__tsearch): Use libc_hidden_def.
(__tfind): Likewise.
(__tdelete): Likewise.
(__twalk): Likewise.
* misc/Versions (libc): Add __tdelete, __tfind, __tsearch and
__twalk to GLIBC_PRIVATE.
* include/search.h (__tsearch): Use libc_hidden_proto.
(__tfind): Likewise.
(__tdelete): Likewise.
(__twalk): Likewise.
* nptl/sem_close.c (sem_close): Call __twalk instead of twalk.
Call __tdelete instead of tdelete.
* nptl/sem_open.c (check_add_mapping): Call __tfind instead of
tfind. Call __tsearch instead of tsearch.
* sysdeps/sparc/sparc32/sem_open.c (check_add_mapping): Likewise.
* conform/Makefile (test-xfail-POSIX/semaphore.h/linknamespace):
Remove variable.
(test-xfail-POSIX2008/semaphore.h/linknamespace): Likewise.
Some of the cfi annotations used incorrect sign.
* sysdeps/aarch64/dl-tlsdesc.S (_dl_tlsdesc_return_lazy): Fix
cfi_adjust_cfa_offset argument.
(_dl_tlsdesc_undefweak, _dl_tlsdesc_dynamic): Likewise.
(_dl_tlsdesc_resolve_rela, _dl_tlsdesc_resolve_hold): Likewise.
Lazy TLSDESC initialization needs to be synchronized with concurrent TLS
accesses. The TLS descriptor contains a function pointer (entry) and an
argument that is accessed from the entry function. With lazy initialization
the first call to the entry function updates the entry and the argument to
their final value. A final entry function must make sure that it accesses an
initialized argument, this needs synchronization on systems with weak memory
ordering otherwise the writes of the first call can be observed out of order.
There are at least two issues with the current code:
tlsdesc.c (i386, x86_64, arm, aarch64) uses volatile memory accesses on the
write side (in the initial entry function) instead of C11 atomics.
And on systems with weak memory ordering (arm, aarch64) the read side
synchronization is missing from the final entry functions (dl-tlsdesc.S).
This patch only deals with aarch64.
* Write side:
Volatile accesses were replaced with C11 relaxed atomics, and a release
store was used for the initialization of entry so the read side can
synchronize with it.
* Read side:
TLS access generated by the compiler and an entry function code is roughly
ldr x1, [x0] // load the entry
blr x1 // call it
entryfunc:
ldr x0, [x0,#8] // load the arg
ret
Various alternatives were considered to force the ordering in the entry
function between the two loads:
(1) barrier
entryfunc:
dmb ishld
ldr x0, [x0,#8]
(2) address dependency (if the address of the second load depends on the
result of the first one the ordering is guaranteed):
entryfunc:
ldr x1,[x0]
and x1,x1,#8
orr x1,x1,#8
ldr x0,[x0,x1]
(3) load-acquire (ARMv8 instruction that is ordered before subsequent
loads and stores)
entryfunc:
ldar xzr,[x0]
ldr x0,[x0,#8]
Option (1) is the simplest but slowest (note: this runs at every TLS
access), options (2) and (3) do one extra load from [x0] (same address
loads are ordered so it happens-after the load on the call site),
option (2) clobbers x1 which is problematic because existing gcc does
not expect that, so approach (3) was chosen.
A new _dl_tlsdesc_return_lazy entry function was introduced for lazily
relocated static TLS, so non-lazy static TLS can avoid the synchronization
cost.
[BZ #18034]
* sysdeps/aarch64/dl-tlsdesc.h (_dl_tlsdesc_return_lazy): Declare.
* sysdeps/aarch64/dl-tlsdesc.S (_dl_tlsdesc_return_lazy): Define.
(_dl_tlsdesc_undefweak): Guarantee TLSDESC entry and argument load-load
ordering using ldar.
(_dl_tlsdesc_dynamic): Likewise.
(_dl_tlsdesc_return_lazy): Likewise.
* sysdeps/aarch64/tlsdesc.c (_dl_tlsdesc_resolve_rela_fixup): Use
relaxed atomics instead of volatile and synchronize with release store.
(_dl_tlsdesc_resolve_hold_fixup): Use relaxed atomics instead of
volatile.
* elf/tlsdeschtab.h (_dl_tlsdesc_resolve_early_return_p): Likewise.
Various functions in XPG4 bring in references to getlogin_r, which is
not in XPG4; this is also a bug for some older POSIX versions which
aren't yet covered by the linknamespace tests. This patch fixes this
by making getlogin_r into a weak alias for __getlogin_r and using
__getlogin_r as needed.
Tested for x86_64 and x86 (testsuite, and that disassembly of
installed stripped shared libraries is unchanged by the patch).
[BZ #18527]
* login/getlogin_r.c (getlogin_r): Rename to __getlogin_r and
define as weak alias of __getlogin_r. Use libc_hidden_weak.
* sysdeps/mach/hurd/getlogin_r.c (getlogin_r): Likewise.
* sysdeps/unix/getlogin_r.c (getlogin_r): Likewise.
* sysdeps/unix/sysv/linux/getlogin_r.c (getlogin_r): Likewise.
* include/unistd.h (__getlogin_r): Declare. Use
libc_hidden_proto.
* posix/glob.c (glob): Call __getlogin_r instead of getlogin_r.
* conform/Makefile (test-xfail-XPG3/glob.h/linknamespace): Remove
variable.
(test-xfail-XPG3/wordexp.h/linknamespace): Likewise.
(test-xfail-XPG4/glob.h/linknamespace): Likewise.
(test-xfail-XPG4/wordexp.h/linknamespace): Likewise.
aio_* bring in references to pread, which isn't in all the standards
containing aio_* (as a reference from one library to another, this is
a bug for dynamic as well as static linking). This patch fixes this
by using __libc_pread instead, exporting that function from libc at
symbol version GLIBC_PRIVATE; the code, with conditionals that may
call either __pread64 or __libc_pread, becomes exactly analogous to
that elsewhere in the same file that may call either __pwrite64 or
__libc_pwrite.
Tested for x86_64 and x86 (testsuite, and comparison of disassembly of
installed shared libraries). libc changes because of the PLT entry
for the newly exported __libc_pread; librt changes because of
assertion line numbers and PLT rearrangement; other stripped installed
shared libraries do not change.
[BZ #18519]
* posix/Versions (libc): Export __libc_pread at version
GLIBC_PRIVATE.
* sysdeps/pthread/aio_misc.c (handle_fildes_io): Call __libc_pread
instead of pread.
* conform/Makefile (test-xfail-POSIX/aio.h/linknamespace): Remove
variable.
Here is implementation of vectorized sin containing SSE, AVX,
AVX2 and AVX512 versions according to Vector ABI
<https://groups.google.com/forum/#!topic/x86-64-abi/LmppCfN1rZ4>.
* bits/libm-simd-decl-stubs.h: Added stubs for sin.
* math/bits/mathcalls.h: Added sin declaration with __MATHCALL_VEC.
* sysdeps/unix/sysv/linux/x86_64/libmvec.abilist: New versions added.
* sysdeps/x86/fpu/bits/math-vector.h: SIMD declaration for sin.
* sysdeps/x86_64/fpu/Makefile (libmvec-support): Added new files.
* sysdeps/x86_64/fpu/Versions: New versions added.
* sysdeps/x86_64/fpu/libm-test-ulps: Regenerated.
* sysdeps/x86_64/fpu/multiarch/Makefile (libmvec-sysdep_routines): Added
build of SSE, AVX2 and AVX512 IFUNC versions.
* sysdeps/x86_64/fpu/multiarch/svml_d_sin2_core.S: New file.
* sysdeps/x86_64/fpu/multiarch/svml_d_sin2_core_sse4.S: New file.
* sysdeps/x86_64/fpu/multiarch/svml_d_sin4_core.S: New file.
* sysdeps/x86_64/fpu/multiarch/svml_d_sin4_core_avx2.S: New file.
* sysdeps/x86_64/fpu/multiarch/svml_d_sin8_core.S: New file.
* sysdeps/x86_64/fpu/multiarch/svml_d_sin8_core_avx512.S: New file.
* sysdeps/x86_64/fpu/svml_d_sin2_core.S: New file.
* sysdeps/x86_64/fpu/svml_d_sin4_core.S: New file.
* sysdeps/x86_64/fpu/svml_d_sin4_core_avx.S: New file.
* sysdeps/x86_64/fpu/svml_d_sin8_core.S: New file.
* sysdeps/x86_64/fpu/svml_d_sin_data.S: New file.
* sysdeps/x86_64/fpu/svml_d_sin_data.h: New file.
* sysdeps/x86_64/fpu/test-double-vlen2-wrappers.c: Added vector sin test.
* sysdeps/x86_64/fpu/test-double-vlen2.c: Likewise.
* sysdeps/x86_64/fpu/test-double-vlen4-avx2-wrappers.c: Likewise.
* sysdeps/x86_64/fpu/test-double-vlen4-avx2.c: Likewise.
* sysdeps/x86_64/fpu/test-double-vlen4-wrappers.c: Likewise.
* sysdeps/x86_64/fpu/test-double-vlen4.c: Likewise.
* sysdeps/x86_64/fpu/test-double-vlen8-wrappers.c: Likewise.
* sysdeps/x86_64/fpu/test-double-vlen8.c: Likewise.
* NEWS: Mention addition of x86_64 vector sin.
Binutils 2.24 doesn't support some AVX512 instructions with ZMM
registers, so we need add more strict check.
* configure.ac: Added more strict check.
* configure: Regenerated.
