of NaNs before possible returning a NaN.
The remquo*() and remainder*() functions should now give bitwise identical
results across arches and implementations, and bitwise consistent results
(with lower precisions having truncated mantissas) across precisions. x86
already had consistency across amd64 and i386 and precisions by using the
i387 consistently and normally not using the C versions. Inconsistencies
for C reqmquol() were first detected on sparc64.
Remove double second clearing of the sign bit and extra blank lines.
remainder*(x, y) and remquo*(x, y, quo) were broken for y = 0 by changing
multiplication by y to addition of y. (When y is 0, the result should be
NaN but became 1 for finite x.)
Use a new macro nan_mix_op() to give more control over the mixing, and
expand comments.
Recent re-testing missed finding this bug since I only tested the macro
version on amd64 and i386 and these arches don't use the C versions (they
use either asm versions or builtins).
Reported by: enh via freebsd-numerics
This is a follow-up to r336299.
* lib/msun/Makefile:
. Remove polevll.c
* lib/msun/ld80/e_powl.c:
. Copy contents of polevll.c to here. This is the only consumer of
these functions. Make functions 'static inline'.
. Make reducl a 'static inline' function.
* lib/msun/man/exp.3:
. Remove BUGS section that no longer applies.
* lib/msun/src/math_private.h:
. Remove prototypes of __p1evll() and __polevll()
* lib/msun/src/s_cpow.c:
* lib/msun/src/s_cpowf.c:
* lib/msun/src/s_cpowl.c
. Include math_private.h.
. Use the CMPLX macro from either C99 or math_private.h (depends on
compiler support) instead of the problematic use of complex I.
Submitted by: Steve Kargl <sgk@troutmask.apl.washington.edu>
PR: 229876
MFC after: 1 week
This was open-coded in range reduction for trig and exp functions. Now
there are 3 static inline functions rnint[fl]() that replace open-coded
expressions, and type-generic irint() and i64rint() macros that hide the
complications for efficiently using non-generic irint() and irintl()
functions and casts.
Special details:
ld128/e_rem_pio2l.h needs to use i64rint() since it needs a 46-bit integer
result. Everything else only needs a (less than) 32-bit integer result so
uses irint().
Float and double cases now use float_t and double_t locally instead of
STRICT_ASSIGN() to avoid bugs in extra precision.
On amd64, inline asm is now only used for irint() on long doubles. The SSE
asm for irint() on amd64 only existed because the ifdef tangles made the
correct method of simply casting to int for this case non-obvious.
cc1: warnings being treated as errors
/usr/src/lib/msun/src/s_cpow.c: In function 'cpow':
/usr/src/lib/msun/src/s_cpow.c:63: warning: implicit declaration of function 'CMPLX'
This is a follow-up to r336299.
* lib/msun/Makefile:
. Remove polevll.c
* lib/msun/ld80/e_powl.c:
. Copy contents of polevll.c to here. This is the only consumer of
these functions. Make functions 'static inline'.
. Make reducl a 'static inline' function.
* lib/msun/man/exp.3:
. Remove BUGS section that no longer applies.
* lib/msun/src/math_private.h:
. Remove prototypes of __p1evll() and __polevll()
* lib/msun/src/s_cpow.c:
* lib/msun/src/s_cpowf.c:
* lib/msun/src/s_cpowl.c
. Use the CMPLX macro from either C99 or math_private.h (depends of
compiler support) instead of the problematic use of complex I.
Submitted by: Steve Kargl <sgk@troutmask.apl.washington.edu>
PR: 229876
MFC after: 1 week
with 1 huge component and 1 tiny (but nowhere near denormal) component.
Rescale earlier so that a scale factor of 2 can be combined with a non-
scale divisor of 2, so that the division doesn't shift out a bit. In the
usual case where the scale factor is just 1, the division may shift out a
bit, but then the underflow is not spurious and the inaccuracies are harder
to fix.
Remove the STDC CX_LIMITED_RANGE pragma and its verbose comment. We still
don't have any C99 compilers (that support fenv pragmas), and if we did
then there are thousands of other places in libm that would need to use
them more than here.
The other cleanups are smaller.
and csqrtl().
When one component is huge and the other is tiny, scaling down the tiny
component gave spurious underflow.
When both components are denormal, not scaling them up gave inaccuracies
of 34+ ulps on not very carefully selected args. Fixing this reduces the
maximum error to 1.6 ulps on the same set of args (mosly not denormal ones).
The scaling used multiplication of a complex variable by 2, but clang messes
this on amd64 up by losing the sign of -0.0. Calculate the components
separately, as is well known to be needed for operations on more exceptional
values.
independent of the precision in most cases. This is mainly to simplify
checking for errors. r176266 did this for e_pow[f].c using a less
refined expression that often didn't work. r176276 fixes an error in
the log message for r176266. The main refinement is to always expand
to long double precision. See old log messages (especially these 2)
and the comment on the macro for more general details.
Specific details:
- using nan_mix() consistently for the new and old pow*() functions was
the only thing needed to make my consistency test for powl() vs pow()
pass on amd64.
- catrig[fl].c already had all the refinements, but open-coded.
- e_atan2[fl].c, e_fmod[fl].c and s_remquo[fl] only had primitive NaN
mixing.
- e_hypot[fl].c already had a different refined version of r176266. Refine
this further. nan_mix() is not directly usable here since we want to
clear the sign bit.
- e_remainder[f].c already had an earlier version of r176266.
- s_ccosh[f].c,/s_csinh[f].c already had a version equivalent to r176266.
Refine this further. nan_mix() is not directly usable here since the
expression has to handle some non-NaN cases.
- s_csqrt.[fl]: the mixing was special and mostly wrong. Partially fix the
special version.
- s_ctanh[f].c already had a version of r176266.
This corresponds to the latest status (hasn't changed in 9+
years) from openbsd of ld80/ld128 powl, and source cpowf, cpow,
cpowl (the complex power functions for float complex, double
complex, and long double complex) which are required for C99
compliance and were missing from FreeBSD. Also required for
some numerical codes using complex numbered Hamiltonians.
Thanks to jhb for tracking down the issue with making
weak_reference compile on powerpc.
When asked to review, bde said "I don't like it" - but
provided no actionable feedback or superior implementations.
Discussed with: jhb
Submitted by: jmd
Differential Revision: https://reviews.freebsd.org/D15919
Remove unnecessary casts, use integer literal constants instead of
floating point constants where possible, and introduce three const
static variables to hold 0.5, 0.25, and 1/3.
PR: 229420
Submitted by: Steve Kargl <sgk@troutmask.apl.washington.edu>
MFC after: 1 week
As a component of atan2(y, x), the case of x == 1.0 is farmed out to
atan(y). The current implementation of this comparison is vulnerable
to signed integer underflow (that is, undefined behavior), and it's
performed in a somewhat more complicated way than it need be. Change
it to not be quite so cute, rather directly comparing the high/low
bits of x to the specific IEEE-754 bit pattern that encodes 1.0.
Note that while there are three different e_atan* files in the
relevant directory, only this one needs fixing. e_atan2f.c already
compares against the full bit pattern encoding 1.0f, while
e_atan2l.cuses bitwise-ands/ors/nots and so doesn't require a change.
Closes#130
Submitted by: Jeff Walden (@jswalden github PR #130)
Reviewed by: bde
MFC After: 1 month
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using mis-identified many licenses so this was mostly a manual - error
prone - task.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
LDBL_MAX is broken on i386:
https://lists.freebsd.org/pipermail/freebsd-numerics/2012-September/000288.html
Gcc has produced +Infinity for LDBL_MAX on i386 and amd64 with -m32
for some time, and newer versions of gcc are now warning that the
"floating constant exceeds range of 'long double'". Avoid this by
referring to proxy values instead.
Reviewed by: bde
Approved by: markj (mentor)
Sponsored by: Dell EMC Isilon
LDBL_MAX is broken on i386:
https://lists.freebsd.org/pipermail/freebsd-numerics/2012-September/000288.html
Gcc has produced +Infinity for LDBL_MAX on i386 and amd64 with -m32
for some time, and newer versions of gcc are now warning that the
"floating constant exceeds range of 'long double'". Avoid this by
referring to half the value of LDBL_MAX instead.
Reviewed by: bde
Approved by: markj (mentor)
Sponsored by: Dell EMC Isilon
The primary benefit of these functions is that argument
reduction is done once instead of twice in independent
calls to sin() and cos().
* lib/msun/Makefile:
. Add s_sincos[fl].c to the build.
. Add sincos.3 documentation.
. Add appropriate MLINKS.
* lib/msun/Symbol.map:
. Expose sincos[fl] symbols in dynamic libm.so.
* lib/msun/man/sincos.3:
. Documentation for sincos[fl].
* lib/msun/src/k_sincos.h:
. Kernel for sincos() function. This merges the individual kernels
for sin() and cos(). The merger offered an opportunity to re-arrange
the individual kernels for better performance.
* lib/msun/src/k_sincosf.h:
. Kernel for sincosf() function. This merges the individual kernels
for sinf() and cosf(). The merger offered an opportunity to re-arrange
the individual kernels for better performance.
* lib/msun/src/k_sincosl.h:
. Kernel for sincosl() function. This merges the individual kernels
for sinl() and cosl(). The merger offered an opportunity to re-arrange
the individual kernels for better performance.
* lib/msun/src/math.h:
. Add prototytpes for sincos[fl]().
* lib/msun/src/math_private.h:
. Add RETURNV macros. This is needed to reset fpsetprec on I386
hardware for a function with type void.
* lib/msun/src/s_sincos.c:
. Implementation of sincos() where sin() and cos() were merged into
one routine and possibly re-arranged for better performance.
* lib/msun/src/s_sincosf.c:
. Implementation of sincosf() where sinf() and cosf() were merged into
one routine and possibly re-arranged for better performance.
* lib/msun/src/s_sincosl.c:
. Implementation of sincosl() where sinl() and cosl() were merged into
one routine and possibly re-arranged for better performance.
PR: 215977, 218300
Submitted by: Steven G. Kargl <sgk@troutmask.apl.washington.edu>
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D10765
an inexact floating point exception. The variable cannot be eliminated,
unfortunately, otherwise the desired addition triggering the exception
will be emitted neither by clang, nor by gcc.
Reviewed by: Steve Kargl, bde
MFC after: 3 days
s_{fabs,fmax,logb,scalb}{,f,l}.c may be built elsewhere with a higher
WARNS setting.
Reviewed by: ed
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D8061
- Fix a case where NaNs were not mixed correctly and signalling NaNs were
not converted to quiet NaNs.
- Eliminate two negations from ctan(z).
In collaboration with: bde
but must still satisfy csinh(conj(z)) == conj(csinh(z)) and csinh(-z) ==
-csinh(z). This allows eliminating two negations from csin(z).
In collaboration with: bde
and qone[f]() were marked as __inline, but their forward
declarations were not updated. Fix the forward declarations
to match the actual function declarations.
Requested by: bde
should raise a divide-by-zero floating point exception for x = +-0
and an invalid floating point exception for x < 0 including x = -Inf.
Update the code to raise the exception and update the documentation
with hopefully better description of the behavior.
Reviewed by: bde (code only)
values for the different invervals were not converted correctly.
Adjust the threshold values to values, which should agree with the
comments.
Reported by: cognet (j1f only)
Discussed with: pfg, bde
Reviewed by: bde
Drop an unnecessary check in some calculations. The check
would have Coverity falsely conclude that variables could
be left undefined.
Discussed with: kargl, bde
Reviewed by: bde
within [INT_MIN, INT_MAX] where the magnitude of the lower
and upper bounds are sufficiently large to span the range of
scalbn[fl].
While here, remove the GNU style bug in the function declarations.
Reviewed by: bde, pfg
The changes unrelated to the bug in r277948 made
the code very difficult to understand to both
coverity and regular humans so take a step back
to something that is much easier to understand
for both and follows better the original code.
CID: 1267992, 1267993, 1267994
Discussed with: kargl
This fixes evaluation of exceptional values in scalblnl().
While here, simplify the code as suggested by Bruce Evans.
Reported by: clang static analyzer
MFC after: 1 week