The i386 implementations of nearbyint functions, and x86_64
nearbyintl, contain code to mask the "inexact" exception. However,
the fnstenv instruction has the effect of masking all exceptions, so
this masking code has been redundant since fnstenv was added to those
implementations (by commit 846d9a4a3acdb4939ca7bf6aed48f9f6f26911be;
commit 71d1b0166b added the test
math/test-nearbyint-except-2.c that verifies these functions do work
when called with "inexact" traps enabled); this patch removes the
redundant code.
Tested for x86_64 and x86.
* sysdeps/i386/fpu/s_nearbyint.S (__nearbyint): Do not mask
"inexact" exceptions after fnstenv.
* sysdeps/i386/fpu/s_nearbyintf.S (__nearbyintf): Likewise.
* sysdeps/i386/fpu/s_nearbyintl.S (__nearbyintl): Likewise.
* sysdeps/x86_64/fpu/s_nearbyintl.S (__nearbyintl): Likewise.
fdim suffers from double rounding on i386 because subtracting two
double values can produce an inexact long double value exactly half
way between two double values. This patch fixes this by creating an
i386-specific version of fdim - C, based on the generic version,
unlike the previous .S version - which sets the x87 precision control
to double precision for the subtraction and then restores it
afterwards. As noted in the comment added, there are no issues of
double rounding for subnormals (a case that setting precision control
does not address) because subtraction cannot produce an inexact result
in the subnormal range.
Tested for x86_64 and x86.
[BZ #20255]
* sysdeps/i386/fpu/s_fdim.c: New file. Based on math/s_fdim.c.
* math/libm-test.inc (fdim_test_data): Add another test.
Some architectures have their own versions of fdim functions, which
are missing errno setting (bug 6796) and may also return sNaN instead
of qNaN for sNaN input, in the case of the x86 / x86_64 long double
versions (bug 20256).
These versions are not actually doing anything that a compiler
couldn't generate, just straightforward comparisons / arithmetic (and,
in the x86 / x86_64 case, testing for NaNs with fxam, which isn't
actually needed once you use an unordered comparison and let the NaNs
pass through the same subtraction as non-NaN inputs). This patch
removes the x86 / x86_64 / powerpc versions, so that those
architectures use the generic C versions, which correctly handle
setting errno and deal properly with sNaN inputs. This seems better
than dealing with setting errno in lots of .S versions.
The i386 versions also return results with excess range and precision,
which is not appropriate for a function exactly defined by reference
to IEEE operations. For errno setting to work correctly on overflow,
it's necessary to remove excess range with math_narrow_eval, which
this patch duly does in the float and double versions so that the
tests can reliably pass on x86. For float, this avoids any double
rounding issues as the long double precision is more than twice that
of float. For double, double rounding issues will need to be
addressed separately, so this patch does not fully fix bug 20255.
Tested for x86_64, x86 and powerpc.
[BZ #6796]
[BZ #20255]
[BZ #20256]
* math/s_fdim.c: Include <math_private.h>.
(__fdim): Use math_narrow_eval on result.
* math/s_fdimf.c: Include <math_private.h>.
(__fdimf): Use math_narrow_eval on result.
* sysdeps/i386/fpu/s_fdim.S: Remove file.
* sysdeps/i386/fpu/s_fdimf.S: Likewise.
* sysdeps/i386/fpu/s_fdiml.S: Likewise.
* sysdeps/i386/i686/fpu/s_fdim.S: Likewise.
* sysdeps/i386/i686/fpu/s_fdimf.S: Likewise.
* sysdeps/i386/i686/fpu/s_fdiml.S: Likewise.
* sysdeps/powerpc/fpu/s_fdim.c: Likewise.
* sysdeps/powerpc/fpu/s_fdimf.c: Likewise.
* sysdeps/powerpc/powerpc32/fpu/s_fdim.c: Likewise.
* sysdeps/powerpc/powerpc64/fpu/s_fdim.c: Likewise.
* sysdeps/x86_64/fpu/s_fdiml.S: Likewise.
* math/libm-test.inc (fdim_test_data): Expect errno setting on
overflow. Add sNaN tests.
Various implementations of frexp functions return sNaN for sNaN
input. This patch fixes them to add such arguments to themselves so
that qNaN is returned.
Tested for x86_64, x86, mips64 and powerpc.
[BZ #20250]
* sysdeps/i386/fpu/s_frexpl.S (__frexpl): Add non-finite input to
itself.
* sysdeps/ieee754/dbl-64/s_frexp.c (__frexp): Add non-finite or
zero input to itself.
* sysdeps/ieee754/dbl-64/wordsize-64/s_frexp.c (__frexp):
Likewise.
* sysdeps/ieee754/flt-32/s_frexpf.c (__frexpf): Likewise.
* sysdeps/ieee754/ldbl-128/s_frexpl.c (__frexpl): Likewise.
* sysdeps/ieee754/ldbl-128ibm/s_frexpl.c (__frexpl): Likewise.
* sysdeps/ieee754/ldbl-96/s_frexpl.c (__frexpl): Likewise.
* math/libm-test.inc (frexp_test_data): Add sNaN tests.
The i386/x86_64 versions of log2l return sNaN for sNaN input. This
patch fixes them to add NaN inputs to themselves so that qNaN is
returned in this case.
Tested for x86_64 and x86.
[BZ #20235]
* sysdeps/i386/fpu/e_log2l.S (__ieee754_log2l): Add NaN input to
itself.
* sysdeps/x86_64/fpu/e_log2l.S (__ieee754_log2l): Likewise.
* math/libm-test.inc (log2_test_data): Add sNaN tests.
The i386/x86_64 versions of log1pl return sNaN for sNaN input. This
patch fixes them to add a NaN input to itself so that qNaN is returned
in this case.
Tested for x86_64 and x86.
[BZ #20229]
* sysdeps/i386/fpu/s_log1pl.S (__log1pl): Add NaN input to itself.
* sysdeps/x86_64/fpu/s_log1pl.S (__log1pl): Likewise.
* math/libm-test.inc (log1p_test_data): Add sNaN tests.
The i386/x86_64 versions of log10l return sNaN for sNaN input. This
patch fixes them to add a NaN input to itself so that qNaN is returned
in this case.
Tested for x86_64 and x86.
[BZ #20228]
* sysdeps/i386/fpu/e_log10l.S (__ieee754_log10l): Add NaN input to
itself.
* sysdeps/x86_64/fpu/e_log10l.S (__ieee754_log10l): Likewise.
* math/libm-test.inc (log10_test_data): Add sNaN tests.
The i386/x86_64 versions of logl return sNaN for sNaN input. This
patch fixes them to add a NaN input to itself so that qNaN is returned
in this case.
Tested for x86_64 and x86 (including a build for i586 to cover the
non-i686 logl version).
[BZ #20227]
* sysdeps/i386/fpu/e_logl.S (__ieee754_logl): Add NaN input to
itself.
* sysdeps/i386/i686/fpu/e_logl.S (__ieee754_logl): Likewise.
* sysdeps/x86_64/fpu/e_logl.S (__ieee754_logl): Likewise.
* math/libm-test.inc (log_test_data): Add sNaN tests.
The i386 and x86_64 implementations of expl, exp10l and expm1l (code
shared between the functions) return sNaN for sNaN input. This patch
fixes them to add NaN inputs to themselves so that qNaN is returned in
this case.
Tested for x86_64 and x86.
[BZ #20226]
* sysdeps/i386/fpu/e_expl.S (IEEE754_EXPL): Add NaN argument to
itself.
* sysdeps/x86_64/fpu/e_expl.S (IEEE754_EXPL): Likewise.
* math/libm-test.inc (exp_test_data): Add sNaN tests.
(exp10_test_data): Likewise.
(expm1_test_data): Likewise.
The i386 version of cbrtl returns sNaN (without raising any
exceptions) for sNaN input. This patch fixes it to add non-finite
arguments to themselves (the code path in question is also reached for
zero arguments, for which adding them to themselves is also harmless),
so that "invalid" is raised and qNaN returned.
Tested for x86_64 and x86.
[BZ #20224]
* sysdeps/i386/fpu/s_cbrtl.S (__cbrtl): Add non-finite or zero
argument to itself.
* math/libm-test.inc (cbrt_test_data): Add sNaN tests.
The i386 version of atanhl returns sNaN for sNaN input. This patch
fixes it to add NaN arguments to themselves so it returns qNaN in this
case.
Tested for x86_64 and x86.
[BZ #20219]
* sysdeps/i386/fpu/e_atanhl.S (__ieee754_atanhl): Add NaN argument
to itself.
* math/libm-test.inc (atanh_test_data): Add sNaN tests.
The i386 version of asinhl returns sNaN (without raising any
exceptions) for sNaN input. This patch fixes it to add non-finite
arguments to themselves, so that "invalid" is raised and qNaN
returned.
Tested for x86_64 and x86.
[BZ #20218]
* sysdeps/i386/fpu/s_asinhl.S (__asinhl): Add non-finite argument
to itself.
* math/libm-test.inc (asinh_test_data): Add sNaN tests.
The x86 / x86_64 implementation of nextafterl (also used for
nexttowardl) produces incorrect results (NaNs) when negative
subnormals, the low 32 bits of whose mantissa are zero, are
incremented towards zero. This patch fixes this by disabling the
logic to decrement the exponent in that case.
Tested for x86_64 and x86.
[BZ #20205]
* sysdeps/i386/fpu/s_nextafterl.c (__nextafterl): Do not adjust
exponent when incrementing negative subnormal with low mantissa
word zero.
* math/libm-test.inc (nextafter_test_data) [TEST_COND_intel96]:
Add another test.
In static executable, since init_cpu_features is called early from
__libc_start_main, there is no need to call it again in dl_platform_init.
[BZ #20072]
* sysdeps/i386/dl-machine.h (dl_platform_init): Call
init_cpu_features only if SHARED is defined.
* sysdeps/x86_64/dl-machine.h (dl_platform_init): Likewise.
Merge x86 ifunc-defines.sym with x86 cpu-features-offsets.sym. Remove
x86 ifunc-defines.sym and rtld-global-offsets.sym. No code changes on
i686 and x86-64.
* sysdeps/i386/i686/multiarch/Makefile (gen-as-const-headers):
Remove ifunc-defines.sym.
* sysdeps/x86_64/multiarch/Makefile (gen-as-const-headers):
Likewise.
* sysdeps/i386/i686/multiarch/ifunc-defines.sym: Removed.
* sysdeps/x86/rtld-global-offsets.sym: Likewise.
* sysdeps/x86_64/multiarch/ifunc-defines.sym: Likewise.
* sysdeps/x86/Makefile (gen-as-const-headers): Remove
rtld-global-offsets.sym.
* sysdeps/x86_64/multiarch/ifunc-defines.sym: Merged with ...
* sysdeps/x86/cpu-features-offsets.sym: This.
* sysdeps/x86/cpu-features.h: Include <cpu-features-offsets.h>
instead of <ifunc-defines.h> and <rtld-global-offsets.h>.
Move sysdeps/x86_64/cacheinfo.c to sysdeps/x86. No code changes on x86
and x86_64.
* sysdeps/i386/cacheinfo.c: Include <sysdeps/x86/cacheinfo.c>
instead of <sysdeps/x86_64/cacheinfo.c>.
* sysdeps/x86_64/cacheinfo.c: Moved to ...
* sysdeps/x86/cacheinfo.c: Here.
This fixes errors when we inject sse options through CFLAGS and now
that we have -Werror turned on by default this warning turns into an
error on x86:
$ gcc -m32 -march=core2 -mtune=core2 -msse3 -mfpmath=sse -x c /dev/null -S -mno-sse -mno-mmx
/dev/null:1:0: warning: SSE instruction set disabled, using 387 arithmetics
Where as:
$ gcc -m32 -march=core2 -mtune=core2 -msse3 -mfpmath=sse -x c /dev/null -S -mno-sse -mno-mmx -mfpmath=387
Generates no warnings.
Improve strcspn performance using a much faster algorithm. It is kept simple
so it works well on most targets. It is generally at least 10 times faster
than the existing implementation on bench-strcspn on a few AArch64
implementations, and for some tests 100 times as fast (repeatedly calling
strchr on a small string is extremely slow...).
In fact the string/bits/string2.h inlines make no longer sense, as GCC
already uses strlen if reject is an empty string, strchrnul is 5 times as
fast as __strcspn_c1, while __strcspn_c2 and __strcspn_c3 are slower than
the strcspn main loop for large strings (though reject length 2-4 could be
special cased in the future to gain even more performance).
Tested on x86_64, i686, and aarch64.
* string/Version (libc): Add GLIBC_2.24.
* string/strcspn.c (strcspn): Rewrite function.
* string/bits/string2.h (strcspn): Use __builtin_strcspn.
(__strcspn_c1): Remove inline function.
(__strcspn_c2): Likewise.
(__strcspn_c3): Likewise.
* string/string-inline.c
[SHLIB_COMPAT(libc, GLIBC_2_1_1, GLIBC_2_24)] (__strcspn_c1): Add
compatibility symbol.
[SHLIB_COMPAT(libc, GLIBC_2_1_1, GLIBC_2_24)] (__strcspn_c2):
Likewise.
[SHLIB_COMPAT(libc, GLIBC_2_1_1, GLIBC_2_24)] (__strcspn_c3):
Likewise.
* sysdeps/i386/string-inlines.c: Include generic string-inlines.c.
Bug 19848 reports cases where powl on x86 / x86_64 has error
accumulation, for small integer exponents, larger than permitted by
glibc's accuracy goals, at least in some rounding modes. This patch
further restricts the exponent range for which the
small-integer-exponent logic is used to limit the possible error
accumulation.
Tested for x86_64 and x86 and ulps updated accordingly.
[BZ #19848]
* sysdeps/i386/fpu/e_powl.S (p3): Rename to p2 and change value
from 8 to 4.
(__ieee754_powl): Compare integer exponent against 4 not 8.
* sysdeps/x86_64/fpu/e_powl.S (p3): Rename to p2 and change value
from 8 to 4.
(__ieee754_powl): Compare integer exponent against 4 not 8.
* math/auto-libm-test-in: Add more tests of pow.
* math/auto-libm-test-out: Regenerated.
* sysdeps/i386/i686/fpu/multiarch/libm-test-ulps: Update.
* sysdeps/x86_64/fpu/libm-test-ulps: Likewise.
When building on i686, x86_64, and arm, and with NDEBUG, or --with-cpu
there are various variables and functions which are unused based on
these settings.
This patch marks all such variables with __attribute__((unused)) to
avoid the compiler warnings when building with the aformentioned
options.
The i386 ULPs are actually the i686/multiarch ones. The i686/multiarch
float ULPs are more precise as the SSE2 version (when available) uses
double for the cosf and sinf functions.
On the other hand the higher precision of the x86 FPU improves the
precision for a few other math functions.
* sysdeps/i386/fpu/libm-test-ulps: Move to ....
* sysdeps/i386/i686/multiarch/fpu/libm-test-ulps: ...here.
* sysdeps/i386/fpu/libm-test-ulps: Regenerate.
Various math_private.h headers are guarded by "#ifndef
_MATH_PRIVATE_H", but never define the macro. Nothing else defines
the macro either (the generic math_private.h that they include defines
a different macro, _MATH_PRIVATE_H_), so those guards are ineffective.
With the recent inclusion of s_sin.c in s_sincos.c, this breaks the
build for MIPS, since the build of s_sincos.c ends up including
<math_private.h> twice and the MIPS version defines inline functions
such as libc_feholdexcept_mips, without a separate fenv_private.h
header with its own guards such as some architectures have.
This patch fixes all the problem headers to use architecture-specific
guard macro names, and to define those macros in the headers they
guard, just as some architectures already do.
Tested for x86 (testsuite, and that installed shared libraries are
unchanged by the patch), and for mips64 (that it fixes the build).
* sysdeps/arm/math_private.h [!_MATH_PRIVATE_H]: Change guard to
[!ARM_MATH_PRIVATE_H].
[!ARM_MATH_PRIVATE_H] (ARM_MATH_PRIVATE_H): Define macro.
* sysdeps/hppa/math_private.h [!_MATH_PRIVATE_H]: Change guard to
[!HPPA_MATH_PRIVATE_H].
[!HPPA_MATH_PRIVATE_H] (HPPA_MATH_PRIVATE_H): Define macro.
* sysdeps/i386/fpu/math_private.h [!_MATH_PRIVATE_H]: Change guard
to [!I386_MATH_PRIVATE_H].
[!I386_MATH_PRIVATE_H] (I386_MATH_PRIVATE_H): Define macro.
* sysdeps/m68k/m680x0/fpu/math_private.h [!_MATH_PRIVATE_H]:
Change guard to [!M68K_MATH_PRIVATE_H].
[!M68K_MATH_PRIVATE_H] (M68K_MATH_PRIVATE_H): Define macro.
* sysdeps/microblaze/math_private.h [!_MATH_PRIVATE_H]: Change
guard to [!MICROBLAZE_MATH_PRIVATE_H].
[!MICROBLAZE_MATH_PRIVATE_H] (MICROBLAZE_MATH_PRIVATE_H): Define
macro.
* sysdeps/mips/math_private.h [!_MATH_PRIVATE_H]: Change guard to
[!MIPS_MATH_PRIVATE_H].
[!MIPS_MATH_PRIVATE_H] (MIPS_MATH_PRIVATE_H): Define macro.
* sysdeps/nios2/math_private.h [!_MATH_PRIVATE_H]: Change guard to
[!NIO2_MATH_PRIVATE_H].
[!NIO2_MATH_PRIVATE_H] (NIO2_MATH_PRIVATE_H): Define macro.
* sysdeps/tile/math_private.h [!_MATH_PRIVATE_H]: Change guard to
[!TILE_MATH_PRIVATE_H].
[!TILE_MATH_PRIVATE_H] (TILE_MATH_PRIVATE_H): Define macro.
For the -ffinite-math-only versions of various x86_64 and x86 log*
functions, a zero result from log* (1) is returned with incorrect sign
in round-downward mode. This patch fixes this in a similar way to the
previous fixes for the non-*_finite versions of the functions.
Tested for x86_64 and x86 (including an i586 build), together with a
patch that will be applied separately to enable the main libm-test.inc
tests for the finite-math-only functions.
[BZ #19213]
* sysdeps/i386/fpu/e_log.S (__log_finite): Ensure +0 is always
returned for argument 1.
* sysdeps/i386/fpu/e_logf.S (__logf_finite): Likewise.
* sysdeps/i386/fpu/e_logl.S (__logl_finite): Likewise.
* sysdeps/i386/i686/fpu/e_logl.S (__logl_finite): Likewise.
* sysdeps/x86_64/fpu/e_log10l.S (__log10l_finite): Likewise.
* sysdeps/x86_64/fpu/e_log2l.S (__log2l_finite): Likewise.
* sysdeps/x86_64/fpu/e_logl.S (__logl_finite): Likewise.
nextafter and nexttoward fail to set errno on overflow and underflow.
This patch makes them do so in cases that should include all the cases
where such errno setting is required by glibc's goals for when to set
errno (but not all cases of underflow where the result is nonzero and
so glibc's goals do not require errno setting).
Tested for x86_64, x86, mips64 and powerpc.
[BZ #6799]
* math/s_nextafter.c: Include <errno.h>.
(__nextafter): Set errno on overflow and underflow.
* math/s_nexttowardf.c: Include <errno.h>.
(__nexttowardf): Set errno on overflow and underflow.
* sysdeps/i386/fpu/s_nextafterl.c: Include <errno.h>.
(__nextafterl): Set errno on overflow and underflow.
* sysdeps/i386/fpu/s_nexttoward.c: Include <errno.h>.
(__nexttoward): Set errno on overflow and underflow.
* sysdeps/i386/fpu/s_nexttowardf.c: Include <errno.h>.
(__nexttowardf): Set errno on overflow and underflow.
* sysdeps/ieee754/flt-32/s_nextafterf.c: Include <errno.h>.
(__nextafterf): Set errno on overflow and underflow.
* sysdeps/ieee754/ldbl-128/s_nextafterl.c: Include <errno.h>.
(__nextafterl): Set errno on overflow and underflow.
* sysdeps/ieee754/ldbl-128/s_nexttoward.c: Include <errno.h>.
(__nexttoward): Set errno on overflow and underflow.
* sysdeps/ieee754/ldbl-128/s_nexttowardf.c: Include <errno.h>.
(__nexttowardf): Set errno on overflow and underflow.
* sysdeps/ieee754/ldbl-128ibm/s_nextafterl.c: Include <errno.h>.
(__nextafterl): Set errno on overflow and underflow.
* sysdeps/ieee754/ldbl-128ibm/s_nexttoward.c: Include <errno.h>.
(__nexttoward): Set errno on overflow and underflow.
* sysdeps/ieee754/ldbl-128ibm/s_nexttowardf.c: Include <errno.h>.
(__nexttowardf): Set errno on overflow and underflow.
* sysdeps/ieee754/ldbl-96/s_nexttoward.c: Include <errno.h>.
(__nexttoward): Set errno on overflow and underflow.
* sysdeps/ieee754/ldbl-96/s_nexttowardf.c: Include <errno.h>.
(__nexttowardf): Set errno on overflow and underflow.
* sysdeps/ieee754/ldbl-opt/s_nexttowardfd.c: Include <errno.h>.
(__nldbl_nexttowardf): Set errno on overflow and underflow.
* sysdeps/m68k/m680x0/fpu/s_nextafterl.c: Include <errno.h>.
(__nextafterl): Set errno on overflow and underflow.
* math/libm-test.inc (nextafter_test_data): Do not allow errno
setting to be missing on overflow. Add more tests.
(nexttoward_test_data): Likewise.
There are configure tests for the cpuid.h header for x86 / x86_64.
GCC 4.3 and later install this header, so those tests are obsolete.
This patch removes them.
Tested for x86_64 and x86 (testsuite, and that installed shared
libraries are unchanged by the patch).
* sysdeps/i386/configure.ac (cpuid.h): Do not test for header.
* sysdeps/i386/configure: Regenerated.
* sysdeps/x86_64/configure.ac (cpuid.h): Do not test for header.
* sysdeps/x86_64/configure: Regenerated.
fenv_t should include architecture-specific floating-point modes and
status flags. i386 and x86_64 fesetenv limit which bits they use from
the x87 status and control words, when using saved state, and limit
which parts of the state they set to fixed values, when using
FE_DFL_ENV / FE_NOMASK_ENV. The following should be included but are
excluded in at least some cases: status and masking for the "denormal
operand" exception (which isn't part of FE_ALL_EXCEPT); precision
control (explicitly mentioned in Annex F as something that counts as
part of the floating-point environment); MXCSR FZ and DAZ bits (for
FE_DFL_ENV and FE_NOMASK_ENV). This patch arranges for this extra
state to be handled by fesetenv (and thereby by feupdateenv, which
calls fesetenv).
(Note that glibc functions using floating point are not generally
expected to work correctly with non-default values of this state,
especially precision control, but it is still logically part of the
floating-point environment and should be handled as such by fesetenv.
Changes to the state relating to subnormals ought generally to work
with libm functions when the arguments aren't subnormal and neither
are the expected results; that's a consequence of functions avoiding
spurious internal underflows.)
A question arising from this is whether FE_NOMASK_ENV should or should
not mask the "denormal operand" exception. I decided it should mask
that exception. This is the status quo - previously that exception
could only be unmasked by direct manipulation of control registers
(possibly via <fpu_control.h>). In addition, it means that use of
FE_NOMASK_ENV leaves a floating-point environment the same as could be
obtained by fesetenv (FE_DFL_ENV); feenableexcept (FE_ALL_EXCEPT);,
rather than an environment in which an exception is unmasked that
could only be masked again by using fesetenv with FE_DFL_ENV (or a
previously saved environment) - this exception not being usable with
other <fenv.h> functions because it's outside FE_ALL_EXCEPT.
Tested for x86_64 and x86.
[BZ #16068]
* sysdeps/i386/fpu/fesetenv.c: Include <fpu_control.h>.
(FE_ALL_EXCEPT_X86): New macro.
(__fesetenv): Use FE_ALL_EXCEPT_X86 in most places instead of
FE_ALL_EXCEPT. Ensure precision control is included in
floating-point state. Ensure that FE_DFL_ENV and FE_NOMASK_ENV
handle "denormal operand exception" and clear FZ and DAZ bits.
* sysdeps/x86_64/fpu/fesetenv.c: Include <fpu_control.h>.
(FE_ALL_EXCEPT_X86): New macro.
(__fesetenv): Use FE_ALL_EXCEPT_X86 in most places instead of
FE_ALL_EXCEPT. Ensure precision control is included in
floating-point state. Ensure that FE_DFL_ENV and FE_NOMASK_ENV
handle "denormal operand exception" and clear FZ and DAZ bits.
* sysdeps/x86/fpu/test-fenv-sse-2.c: New file.
* sysdeps/x86/fpu/test-fenv-x87.c: Likewise.
* sysdeps/x86/fpu/Makefile [$(subdir) = math] (tests): Add
test-fenv-x87 and test-fenv-sse-2.
[$(subdir) = math] (CFLAGS-test-fenv-sse-2.c): New variable.
The i386 and x86_64 versions of fesetenv, when called with FE_DFL_ENV
or FE_NOMASK_ENV as argument, do not clear SSE exceptions raised in
MXCSR. These arguments should, like other fenv_t values, represent
the whole of the floating-point state, so such exceptions should be
cleared; this patch adds the required clearing. (Discovered while
working on bug 16068.)
Tested for x86_64 and x86.
[BZ #19181]
* sysdeps/i386/fpu/fesetenv.c (__fesetenv): Clear already-raised
SSE exceptions when argument is FE_DFL_ENV or FE_NOMASK_ENV.
* sysdeps/x86_64/fpu/fesetenv.c (__fesetenv): Likewise.
* math/test-fenv-clear-main.c: New file.
* math/test-fenv-clear.c: Likewise.
* math/Makefile (tests): Add test-fenv-clear.
* sysdeps/x86/fpu/test-fenv-clear-sse.c: New file.
* sysdeps/x86/fpu/Makefile [$(subdir) = math] (tests): Add
test-fenv-clear-sse.
[$(subdir) = math] (CFLAGS-test-fenv-clear-sse.c): New variable.
There are configure tests for the -mavx2 compiler option. AVX2
support was added in GCC 4.7, so these tests are now obsolete; this
patch removes them.
Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by the patch).
* sysdeps/i386/configure.ac (libc_cv_cc_avx2): Remove configure
test.
* sysdeps/i386/configure: Regenerated.
* sysdeps/x86_64/configure.ac (libc_cv_cc_avx2): Remove configure
test.
* sysdeps/x86_64/configure: Regenerated.
* config.h.in (HAVE_AVX2_SUPPORT): Remove #undef.
* sysdeps/x86_64/multiarch/Makefile (sysdep_routines): Add
memset-avx2 unconditionally instead of conditionally on
[$(config-cflags-avx2) = yes].
* sysdeps/x86_64/multiarch/ifunc-impl-list.c
(__libc_ifunc_impl_list) [HAVE_AVX2_SUPPORT]: Make code
unconditional.
* sysdeps/x86_64/multiarch/memset.S [HAVE_AVX2_SUPPORT]: Likewise.
* sysdeps/x86_64/multiarch/memset_chk.S
[IS_IN (libc) && SHARED && HAVE_AVX2_SUPPORT]: Change conditional
to [IS_IN (libc) && SHARED].
The implementations of nearbyint functions using x87 floating point
(i386 all versions, x86_64 long double only) use the fclex
instruction, which clears any exceptions that were raised before the
function was called. These functions must not clear exceptions that
were raised before they were called.
This patch fixes these functions to save and restore the whole
floating-point environment (fnstenv / fldenv) as the way of avoiding
raising "inexact" (recall that there isn't an x87 instruction for
loading just the status word, so the whole environment has to be saved
and loaded instead - the code already saved and loaded the control
word, which is now obtained from the saved environment after this
patch, to disable traps on "inexact"). In the case of the long double
functions, any "invalid" exception from frndint (applied to a
signaling NaN) needs merging into the saved state; this issue doesn't
apply to the float and double functions because that exception would
have been raised when the argument is loaded, before the environment
is saved.
[BZ #15491]
* sysdeps/i386/fpu/s_nearbyint.S (__nearbyint): Save and restore
floating-point environment instead of clearing all exceptions.
* sysdeps/i386/fpu/s_nearbyintf.S (__nearbyintf): Likewise.
* sysdeps/i386/fpu/s_nearbyintl.S (__nearbyintl): Likewise,
merging in "invalid" exceptions from frndint.
* sysdeps/x86_64/fpu/s_nearbyintl.S (__nearbyintl): Likewise.
* math/test-nearbyint-except.c: New file.
* math/Makefile (tests): Add test-nearbyint-except.
Since x86 _dl_unmap and _dl_make_tlsdesc_dynamic are only used
internally in ld.so, they can be made hidden.
[BZ #19122]
* sysdeps/i386/dl-lookupcfg.h (_dl_unmap): Add attribute_hidden.
* sysdeps/i386/dl-tlsdesc.h (_dl_make_tlsdesc_dynamic):
Likewise.
* sysdeps/x86_64/dl-tlsdesc.h (_dl_make_tlsdesc_dynamic):
Likewise.
* sysdeps/x86_64/dl-lookupcfg.h (_dl_unmap): Likewise.
There is a configure test for assembler support for -mtune=i686. This
option was added in binutils 2.18 so the test is obsolete; this patch
removes it.
Tested for x86 (testsuite, and that installed shared libraries are
unchanged by the patch).
* sysdeps/i386/configure.ac (libc_cv_as_i686): Remove configure
test.
* sysdeps/i386/configure: Regenerated.
* sysdeps/i386/i686/Makefile [$(config-asflags-i686) = yes]: Make
code unconditional.
GCC added support for -mno-vzeroupper in version 4.6. Thus the
configure tests for this support are obsolete, and this patch removes
them.
Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by this patch).
* sysdeps/i386/configure.ac (libc_cv_cc_novzeroupper): Remove
configure test.
* sysdeps/i386/configure: Regenerated.
* sysdeps/x86_64/configure.ac (libc_cv_cc_novzeroupper): Remove
configure test.
* sysdeps/x86_64/configure: Regenerated.
* sysdeps/x86_64/Makefile [$(config-cflags-novzeroupper) = yes]:
Make code unconditional.
GCC added support for -msse4 in version 4.3. Thus the configure tests
for it are obsolete, and this patch removes them.
Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by this patch).
* sysdeps/i386/configure.ac (libc_cv_cc_sse4): Remove configure
test.
* sysdeps/i386/configure: Regenerated.
* sysdeps/i386/i686/multiarch/Makefile
[$(config-cflags-sse4) = yes]: Make code unconditional.
* sysdeps/i386/i686/multiarch/strcspn.S [HAVE_SSE4_SUPPORT]:
Likewise.
* sysdeps/i386/i686/multiarch/strspn.S [HAVE_SSE4_SUPPORT]:
Likewise.
* sysdeps/x86_64/configure.ac (libc_cv_cc_sse4): Remove configure
test.
* sysdeps/x86_64/configure: Regenerated.
* sysdeps/x86_64/multiarch/Makefile [$(config-cflags-sse4) = yes]:
Make code unconditional.
* sysdeps/x86_64/multiarch/strcspn.S [HAVE_SSE4_SUPPORT]:
Likewise.
* sysdeps/x86_64/multiarch/strspn.S [HAVE_SSE4_SUPPORT]: Likewise.
* config.h.in (HAVE_SSE4_SUPPORT): Remove #undef.
ISO C requires overflowing results from nexttoward to be the
appropriate infinity independent of the rounding mode, but some
implementations use a rounding-mode-dependent result (this is the same
issue as was fixed for nextafter in bug 16677). This patch fixes the
problem by making the nexttoward implementations discard the result
from the floating-point computation that forced an overflow exception
and then return the infinity previously computed with integer
arithmetic.
Tested for x86_64, x86, mips64 and powerpc.
[BZ #19059]
* math/s_nexttowardf.c (__nexttowardf): Do not return value from
overflowing computation.
* sysdeps/i386/fpu/s_nexttoward.c (__nexttoward): Likewise.
* sysdeps/i386/fpu/s_nexttowardf.c (__nexttowardf): Likewise.
* sysdeps/ieee754/ldbl-128/s_nexttoward.c (__nexttoward):
Likewise.
* sysdeps/ieee754/ldbl-128/s_nexttowardf.c (__nexttowardf):
Likewise.
* sysdeps/ieee754/ldbl-128ibm/s_nexttoward.c (__nexttoward):
Likewise.
* sysdeps/ieee754/ldbl-128ibm/s_nexttowardf.c (__nexttowardf):
Likewise.
* sysdeps/ieee754/ldbl-96/s_nexttoward.c (__nexttoward): Likewise.
* sysdeps/ieee754/ldbl-96/s_nexttowardf.c (__nexttowardf):
Likewise.
* sysdeps/ieee754/ldbl-opt/s_nexttowardfd.c (__nldbl_nexttowardf):
Likewise.
* math/libm-test.inc (nexttoward_test_data): Add more tests.
The i386 versions of acoshf and acosh raise a spurious "invalid"
exception for an argument that is a quiet NaN with the sign bit set.
The integer arithmetic to detect arguments < 1 also detects -NaN, and
then the computation 0 / 0 in that case raises the exception. This
patch fixes this by using (x - x) / (x - x) as the computation in that
case instead, which will always raise the exception for non-NaN
arguments reaching that code, but not for quiet NaN arguments.
Tested for x86_64 and x86.
[BZ #19032]
* sysdeps/i386/fpu/e_acosh.S (__ieee754_acosh): For arguments < 1,
compute result as (x - x) / (x - x) not as 0 / 0.
* sysdeps/i386/fpu/e_acoshf.S (__ieee754_acoshf): Likewise.
* math/libm-test.inc (acosh_test_data): Add another test of acosh.
For arguments with X^2 + Y^2 close to 1, clog and clog10 avoid large
errors from log(hypot) by computing X^2 + Y^2 - 1 in a way that avoids
cancellation error and then using log1p.
However, the thresholds for using that approach still result in log
being used on argument as large as sqrt(13/16) > 0.9, leading to
significant errors, in some cases above the 9ulp maximum allowed in
glibc libm. This patch arranges for the approach using log1p to be
used in any cases where |X|, |Y| < 1 and X^2 + Y^2 >= 0.5 (with the
existing allowance for cases where one of X and Y is very small),
adjusting the __x2y2m1 functions to work with the wider range of
inputs. This way, log only gets used on arguments below sqrt(1/2) (or
substantially above 1), where the error involved is much less.
Tested for x86_64, x86, mips64 and powerpc. For the ulps regeneration
I removed the existing clog and clog10 ulps before regenerating to
allow any reduced ulps to appear. Tests added include those found by
random test generation to produce large ulps either before or after
the patch, and some found by trying inputs close to the (0.75, 0.5)
threshold where the potential errors from using log are largest.
[BZ #19016]
* sysdeps/generic/math_private.h (__x2y2m1f): Update comment to
allow more cases with X^2 + Y^2 >= 0.5.
* sysdeps/ieee754/dbl-64/x2y2m1.c (__x2y2m1): Likewise. Add -1 as
normal element in sum instead of special-casing based on values of
arguments.
* sysdeps/ieee754/dbl-64/x2y2m1f.c (__x2y2m1f): Update comment.
* sysdeps/ieee754/ldbl-128/x2y2m1l.c (__x2y2m1l): Likewise. Add
-1 as normal element in sum instead of special-casing based on
values of arguments.
* sysdeps/ieee754/ldbl-128ibm/x2y2m1l.c (__x2y2m1l): Likewise.
* sysdeps/ieee754/ldbl-96/x2y2m1.c [FLT_EVAL_METHOD != 0]
(__x2y2m1): Update comment.
* sysdeps/ieee754/ldbl-96/x2y2m1l.c (__x2y2m1l): Likewise. Add -1
as normal element in sum instead of special-casing based on values
of arguments.
* math/s_clog.c (__clog): Handle more cases using log1p without
hypot.
* math/s_clog10.c (__clog10): Likewise.
* math/s_clog10f.c (__clog10f): Likewise.
* math/s_clog10l.c (__clog10l): Likewise.
* math/s_clogf.c (__clogf): Likewise.
* math/s_clogl.c (__clogl): Likewise.
* math/auto-libm-test-in: Add more tests of clog and clog10.
* 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, pow functions can fail to
raise the underflow exception when the result is tiny and inexact but
one or more low bits of the intermediate result that is scaled down
(or, in the i386 case, converted from a wider evaluation format) are
zero. This patch forces the exception in a similar way to previous
fixes, thereby concluding the fixes for known bugs with missing
underflow exceptions currently filed in Bugzilla.
Tested for x86_64, x86, mips64 and powerpc.
[BZ #18825]
* sysdeps/i386/fpu/i386-math-asm.h (FLT_NARROW_EVAL_UFLOW_NONNAN):
New macro.
(DBL_NARROW_EVAL_UFLOW_NONNAN): Likewise.
(LDBL_CHECK_FORCE_UFLOW_NONNAN): Likewise.
* sysdeps/i386/fpu/e_pow.S: Use DEFINE_DBL_MIN.
(__ieee754_pow): Use DBL_NARROW_EVAL_UFLOW_NONNAN instead of
DBL_NARROW_EVAL, reloading the PIC register as needed.
* sysdeps/i386/fpu/e_powf.S: Use DEFINE_FLT_MIN.
(__ieee754_powf): Use FLT_NARROW_EVAL_UFLOW_NONNAN instead of
FLT_NARROW_EVAL. Use separate return path for case when first
argument is NaN.
* sysdeps/i386/fpu/e_powl.S: Include <i386-math-asm.h>. Use
DEFINE_LDBL_MIN.
(__ieee754_powl): Use LDBL_CHECK_FORCE_UFLOW_NONNAN, reloading the
PIC register.
* sysdeps/ieee754/dbl-64/e_pow.c (__ieee754_pow): Use
math_check_force_underflow_nonneg.
* sysdeps/ieee754/flt-32/e_powf.c (__ieee754_powf): Force
underflow for subnormal result.
* sysdeps/ieee754/ldbl-128/e_powl.c (__ieee754_powl): Likewise.
* sysdeps/ieee754/ldbl-128ibm/e_powl.c (__ieee754_powl): Use
math_check_force_underflow_nonneg.
* sysdeps/x86/fpu/powl_helper.c (__powl_helper): Use
math_check_force_underflow.
* sysdeps/x86_64/fpu/x86_64-math-asm.h
(LDBL_CHECK_FORCE_UFLOW_NONNAN): New macro.
* sysdeps/x86_64/fpu/e_powl.S: Include <x86_64-math-asm.h>. Use
DEFINE_LDBL_MIN.
(__ieee754_powl): Use LDBL_CHECK_FORCE_UFLOW_NONNAN.
* math/auto-libm-test-in: Add more tests of pow.
* math/auto-libm-test-out: Regenerated.
Similar to various other bugs in this area, hypot functions can fail
to raise the underflow exception when the result is tiny and inexact
but one or more low bits of the intermediate result that is scaled
down (or, in the i386 case, converted from a wider evaluation format)
are zero. This patch forces the exception in a similar way to
previous fixes.
Note that this issue cannot arise for implementations of hypotf using
double (or wider) for intermediate evaluation (if hypotf should
underflow, that means the double square root is being computed of some
number of the form N*2^-298, for 0 < N < 2^46, which is exactly
represented as a double, and whatever the rounding mode such a square
root cannot have a mantissa with all zeroes after the initial 23
bits). Thus no changes are made to hypotf implementations in this
patch, only to hypot and hypotl.
Tested for x86_64, x86, mips64 and powerpc.
[BZ #18803]
* sysdeps/i386/fpu/e_hypot.S: Use DEFINE_DBL_MIN.
(MO): New macro.
(__ieee754_hypot) [PIC]: Load PIC register.
(__ieee754_hypot): Use DBL_NARROW_EVAL_UFLOW_NONNEG instead of
DBL_NARROW_EVAL.
* sysdeps/ieee754/dbl-64/e_hypot.c (__ieee754_hypot): Use
math_check_force_underflow_nonneg in case where result might be
tiny.
* sysdeps/ieee754/ldbl-128/e_hypotl.c (__ieee754_hypotl):
Likewise.
* sysdeps/ieee754/ldbl-128ibm/e_hypotl.c (__ieee754_hypotl):
Likewise.
* sysdeps/ieee754/ldbl-96/e_hypotl.c (__ieee754_hypotl): Likewise.
* sysdeps/powerpc/fpu/e_hypot.c (__ieee754_hypot): Likewise.
* math/auto-libm-test-in: Add more tests of hypot.
* math/auto-libm-test-out: Regenerated.
sysdeps/i386/fpu/e_atanh.S, unlike all other functions in that
directory, loads the PIC register with its own code using
_GLOBAL_OFFSET_TABLE_, rather than with the LOAD_PIC_REG macro. I see
no good reason for the difference; this patch makes it use the common
macro.
Tested for x86.
* sysdeps/i386/fpu/e_atanh.S (__ieee754_atanh) [PIC]: Use
LOAD_PIC_REG.
