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.
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.
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.
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.
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.
i386 exp, hypot and pow functions can return overflowing and
underflowing values with excess range and precision; ; Wilco
Dijkstra's patches to make isfinite etc. expand inline cause this
pre-existing issue to result in test failures.
This patch fixes those functions to avoid excess range and precision
in their return values. Appropriate macros are added for the repeated
code sequences; in future I'll add more such macros and refactor
existing code forcing underflow (with or without also eliminating
excess range and precision from the return value) to use such macros.
Tested for x86. If, after this patch, you still see x86 libm test
failures with excess range or precision, please file bugs in Bugzilla.
[BZ #18980]
* sysdeps/i386/fpu/i386-math-asm.h (DEFINE_FLT_MIN): New macro.
(DEFINE_DBL_MIN): Likewise.
(FLT_NARROW_EVAL_UFLOW_NONNEG_NAN): Likewise.
(DBL_NARROW_EVAL_UFLOW_NONNEG_NAN): Likewise.
(FLT_NARROW_EVAL_UFLOW_NONNEG): Likewise.
(DBL_NARROW_EVAL_UFLOW_NONNEG): Likewise.
* sysdeps/i386/fpu/e_exp.S: Include <i386-math-asm.h>.
(dbl_min): Replace with use of DEFINE_DBL_MIN.
(__ieee754_exp): Use DBL_NARROW_EVAL_UFLOW_NONNEG_NAN.
(__exp_finite): Use DBL_NARROW_EVAL_UFLOW_NONNEG.
* sysdeps/i386/fpu/e_exp10.S: Include <i386-math-asm.h>.
(dbl_min): Replace with use of DEFINE_DBL_MIN.
(__ieee754_exp10): Use DBL_NARROW_EVAL_UFLOW_NONNEG_NAN.
* sysdeps/i386/fpu/e_exp10f.S: Include <i386-math-asm.h>.
(flt_min): Replace with use of DEFINE_FLT_MIN.
(__ieee754_exp10f): Use FLT_NARROW_EVAL_UFLOW_NONNEG_NAN.
* sysdeps/i386/fpu/e_exp2.S: Include <i386-math-asm.h>.
(dbl_min): Replace with use of DEFINE_DBL_MIN.
(__ieee754_exp2): Use DBL_NARROW_EVAL_UFLOW_NONNEG_NAN.
* sysdeps/i386/fpu/e_exp2f.S: Include <i386-math-asm.h>.
(flt_min): Replace with use of DEFINE_FLT_MIN.
(__ieee754_exp2f): Use FLT_NARROW_EVAL_UFLOW_NONNEG_NAN.
* sysdeps/i386/fpu/e_expf.S: Include <i386-math-asm.h>.
(flt_min): Replace with use of DEFINE_FLT_MIN.
(__ieee754_expf): Use FLT_NARROW_EVAL_UFLOW_NONNEG_NAN.
(__expf_finite): Use FLT_NARROW_EVAL_UFLOW_NONNEG.
* sysdeps/i386/fpu/e_hypot.S: Include <i386-math-asm.h>.
(__ieee754_hypot): Use DBL_NARROW_EVAL.
* sysdeps/i386/fpu/e_hypotf.S: Include <i386-math-asm.h>.
(__ieee754_hypotf): Use FLT_NARROW_EVAL.
* sysdeps/i386/fpu/e_pow.S: Include <i386-math-asm.h>.
(__ieee754_pow): Use DBL_NARROW_EVAL.
* sysdeps/i386/fpu/e_powf.S: Include <i386-math-asm.h>.
(__ieee754_powf): Use FLT_NARROW_EVAL.
* sysdeps/i386/i686/fpu/multiarch/e_expf-sse2.S
(__ieee754_expf_sse2): Convert double-precision result to single
precision.
* sysdeps/i386/fpu/libm-test-ulps: Update.
This patch fixes __ieee754_logl (-LDBL_MAX) on x86_64 and x86 not to
subtract 1 from its argument and so cause spurious overflow in
FE_DOWNWARD mode. (For any argument strictly less than -1, it doesn't
matter whether or not 1 is subtracted before computing log1p, as long
as the result doesn't overflow to -Inf.)
Tested x86_64 and x86. (This particular case lacks test coverage,
since the testsuite doesn't cover -lieee, but it will be covered by
tests after the following patch to test pow in all rounding modes,
which was the context in which this bug was found.)
[BZ #17022]
* sysdeps/i386/fpu/e_logl.S (__ieee754_logl): Do not subtract 1
from arguments -2 or below.
* sysdeps/i386/i686/fpu/e_logl.S (__ieee754_logl): Likewise.
* sysdeps/x86_64/fpu/e_logl.S (__ieee754_logl): Likewise.
According to ISO C Annex F, log (1) should be +0 in all rounding
modes, but some implementations in glibc wrongly return -0 in
round-downward mode (mapping to log1p (x - 1) is problematic because 1
- 1 is -0 in round-downward mode, and log1p (-0) is -0). This patch
fixes this. (It helps with some implementations of other functions
such as acosh, log2 and log10 that call out to log, but not enough to
enable all-rounding-modes testing for those functions without further
fixes to other implementations of them.)
Tested x86_64 and x86 and ulps updated accordingly, and did spot tests
for mips64 for the ldbl-128 fix, and i586 for the sysdeps/i386/fpu
implementations shadowed by those in sysdeps/i386/i686/fpu.
[BZ #16731]
* sysdeps/i386/fpu/e_log.S (__ieee754_log): Take absolute value
when x - 1 is zero.
* sysdeps/i386/fpu/e_logf.S (__ieee754_logf): Likewise.
* sysdeps/i386/fpu/e_logl.S (__ieee754_logl): Likewise.
* sysdeps/i386/i686/fpu/e_logl.S (__ieee754_logl): Likewise.
* sysdeps/ieee754/dbl-64/e_log.c (__ieee754_log): Return +0 when
argument is 1.
* sysdeps/ieee754/ldbl-128/e_logl.c (__ieee754_logl): Likewise.
* sysdeps/x86_64/fpu/e_logl.S: Take absolute value when x - 1 is
zero.
* math/libm-test.inc (log_test): Use ALL_RM_TEST.
* sysdeps/i386/fpu/libm-test-ulps: Update.
* sysdeps/x86_64/fpu/libm-test-ulps: Likewise.
* sysdeps/i386/i686/fpu/multiarch/Makefile (sysdep_routines):
Add s_sinf-sse2, s_conf-sse2.
* sysdeps/i386/i686/fpu/multiarch/s_sinf-sse2.S: New file.
* sysdeps/i386/i686/fpu/multiarch/s_cosf-sse2.S: New file.
* sysdeps/i386/i686/fpu/multiarch/s_sinf.c: New file.
* sysdeps/i386/i686/fpu/multiarch/s_cosf.c: New file.
* sysdeps/ieee754/flt-32/s_sinf.c (SINF, SINF_FUNC): Add macros
for using routine as __sinf_ia32.
Use macro for function declaration and weak_alias.
* sysdeps/ieee754/flt-32/s_cosf.c (COSF, COSF_FUNC): Add macros
for using routine as __cosf_ia32.
Use macro for function declaration and weak_alias.
* sysdeps/i386/i686/fpu/multiarch/e_expf-sse2.S: Fix Copyright.
* sysdeps/i386/i686/fpu/multiarch/e_expf.c: Fix Copyright.
* sysdeps/x86_64/fpu/s_sinf.S: New file.
* sysdeps/x86_64/fpu/s_cosf.S: New file.
* sysdeps/x86_64/fpu/libm-test-ulps: Update.
* math/libm-test.inc (cos_test): Add more test cases.
(sin_test): Likewise.
(sincos_test): Likewise.
2012-05-14 Liubov Dmitrieva <liubov.dmitrieva@gmail.com>
* sysdeps/i386/i686/fpu/multiarch/Makefile: New file.
* sysdeps/i386/i686fpu/multiarch/e_expf.c: New file.
* sysdeps/i386/i686fpu/multiarch/e_expf-ia32.S: New file.
* sysdeps/i386/i686/fpu/multiarch/e_expf-sse2.S: New file.
2001-07-06 Paul Eggert <eggert@twinsun.com>
* manual/argp.texi: Remove ignored LGPL copyright notice; it's
not appropriate for documentation anyway.
* manual/libc-texinfo.sh: "Library General Public License" ->
"Lesser General Public License".
2001-07-06 Andreas Jaeger <aj@suse.de>
* All files under GPL/LGPL version 2: Place under LGPL version
2.1.