Avoid raising unexpected floating point exceptions in libm

When using clang with x86_64 CPUs that support AVX, some floating point
transformations may raise exceptions that would not have been raised by
the original code. To avoid this, use the -fp-exception-behavior=maytrap
flag, introduced in clang 10.0.0.

In particular, this fixes a number of test failures with ctanhf(3) and
ctanf(3), when libm is compiled with -mavx. An unexpected FE_INVALID
exception is then raised, because clang emits vdivps instructions to
perform certain divides. (The vdivps instruction operates on multiple
single-precision float operands simultaneously, but the exceptions may
be influenced by unused parts of the XMM registers. In this particular
case, it was calculating 0 / 0, which results in FE_INVALID.)

If -fp-exception-behavior=maytrap is specified however, clang uses
vdivss instructions instead, which work on one operand, and should not
raise unexpected exceptions.

Reported by: olivier
Reviewed by: arichardson
PR: 254911
Differential Revision: https://reviews.freebsd.org/D29686

(cherry picked from commit 3b00222f156dca5700c839d73e36daf479fa640c)

Only use -fp-exception-behavior=maytrap on x86, for now

After 3b00222f156d, it turns out that clang only supports strict
floating point semantics for SystemZ and x86 at the moment, while for
other architectures it is still experimental.

Therefore, only use -fp-exception-behavior=maytrap on x86 for now,
otherwise this option results in "error: overriding currently
unsupported use of floating point exceptions on this target
[-Werror,-Wunsupported-floating-point-opt]" on other architectures.

Fixes: 3b00222f156d
PR: 254911

(cherry picked from commit bae9fd0b33462e9506c3ac3400089c6dbc4aee8f)

Git Hash: cabc474b2dc9c6741b240e454da86a7ff2ff9f9c
Git Author: dim@FreeBSD.org

libm: squelch -Woverflow from gcc6

Sponsored by: Dell EMC Isilon

(cherry picked from commit 50b06886a715d7be052e1742f7d11ce82928f134)

Git Hash: e7cc5cda88f079b80636aa7f71b0fc671701f77d
Git Author: vangyzen@FreeBSD.org

MFC r327400 (by eadler):

cacos(3): correct spelling of 'I'

In some cases we had 'i' instead of 'I'.

PR: 195517
Submitted by: stephen

MFC r329259 (by eadler):

msun: signed overflow in atan2

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 r334721 (by cem):

clog.3, complex.3: Fix typos and igor style issues

PR: 228783
Reported by: Karsten <freebsd-bugzilla AT kkoenig.net>

MFC r336299 (by mmacy):

msun: add ld80/ld128 powl, cpow, cpowf, cpowl from openbsd

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

MFC r336563:

Recommit r336497: Fix powl, cpow, cpowf, and cpowl imports from OpenBSD

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 r333577:
Add implementations for clog(3), clogf(3), and clogl(3).

PR: 216863

Synchronize most of libm with head as of r323004. This excludes a few
arch-specific updates for powerpcspe, mips and riscv, for which support
has not been merged yet.

Bump __FreeBSD_version for the addition of cacoshl, cacosl, casinhl,
casinl, catanl, catanhl, sincos, sincosf, and sincosl.

MFC r305382 (by bde):

Add asm versions of fmod(), fmodf() and fmodl() on amd64. Add asm
versions of fmodf() amd fmodl() on i387.

fmod is similar to remainder, and the C versions are 3 to 9 times
slower than the asm versions on x86 for both, but we had the strange
mixture of all 6 variants of remainder in asm and only 1 of 6
variants of fmod in asm.

MFC r305384 (by bde):

Disconnect the "optimized" asm variants of cos(), sin() and tan() from
the build on i386. Leave them in the source tree for regression tests.

The asm functions were always much less accurate (by a factor of more
than 10**18 in the worst case). They were faster on old CPUs. But
with each new generation of CPUs they get relatively slower. The
double precision C version's average advantage is about a factor of 2
on Haswell.

The asm functions were already intentionally avoided in float and long
double precision on i386 and in all precisions on amd64. Float
precision and amd64 give larger advantages to the C version. The long
double precision C code and compilers' understanding of long double
precision are not so good, so the i387 is still slightly faster for
long double precision, except for the unimportant subcase of huge args
where the sub-optimal C code now somehow beats the i387 by about a
factor of 2.

MFC r305385 (by bde):

Oops, the previous i386 version of e_fmodf.S and e_fmodl.S was
actually the amd64 version.

MFC r306409 (by emaste):

libm: fix some unused variable (rcsid) and dangling else warnings

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

MFC r306410 (by emaste):

libm: simplify i387 subdir logic with make's :S substitution

MFC r306527 (by emaste):

libm: remove unused variables for LDBL_MANT_DIG != 113

Sponsored by: The FreeBSD Foundation

MFC r306709 (by emaste):

libm: remove unused variables

Sponsored by: The FreeBSD Foundation

MFC r307066 (by br):

Don't use fmaxl/fminl on platforms with no long double support,
use fmax/fmin instead.

This fixes fmaxmin test failure on MIPS64.

Reviewed by: emaste
Sponsored by: DARPA, AFRL
Sponsored by: HEIF5
Differential Revision: https://reviews.freebsd.org/D8216

MFC r308172 (by emaste):

libm: add braces around initialization of subobjects

This cleans up a warning when building libm at higher WARNS levels and
makes the intent more clear. By the C standard the values are assigned
to subobject members in order so this change introduces no functional
change. (6.7.9 20)

Reviewed by: kib
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D8333

MFC r313761 (by mmokhi):

Add casinl() cacosl() catanl() casinhl() cacoshl() catanhl() APIs to msun
to improve C11 conformance.

PR: 216850 216851 216852 216856 216857 216858
Submitted by: mmokhi
Reported by: sgk@troutmask.apl.washington.edu
Reviewed by: bde, mat, theraven
Approved by: bde (src committer), mat (mentor)
Differential Revision: https://reviews.freebsd.org/D9491

MFC r313863 (by mmokhi):

Fix building of r313761 on platforms that
`long double` is alias of `double` (MIPS, etc)

PR: 216850 216851 216852 216856 216857 216858
Reported by: emsate
Reviewed by: bde emaste hselasky
Approved by: bde emaste hselasky
Differential Revision: https://reviews.freebsd.org/D9491

MFC r313864 (by mmokhi):

Add documentations related to new APIs of r313761

PR: 216850 216851 216852 216856 216857 216858
Submitted by: sgk@troutmask.apl.washington.edu
Reported by: sgk@troutmask.apl.washington.edu
Reviewed by: bde emaste hselasky
Approved by: bde emaste hselasky
Differential Revision: https://reviews.freebsd.org/D9491

MFC r314950 (by ngie):

Don't expect :test_large_inputs to fail with i386 anymore

Recent changes (maybe a side-effect of the ATF-ification in r314649)
invalidate the failure expectation.

PR: 205446
Sponsored by: Dell EMC Isilon

MFC r317349 (by pfg):

msun: Remove trailing space in Sunsoft copyright statement.

Submittedby: kargl

MFC r319047 (by mmel):

Implement sincos, sincosf, and sincosl.
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>
Differential Revision: https://reviews.freebsd.org/D10765

MFC r321457 (by ngie):

Mark :reduction as an expected failure

It fails with clang 5.0+.

PR: 220989
Reported by: Jenkins

MFC r322418 (by rlibby):

lib/msun: avoid referring to broken LDBL_MAX

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

MFC r322435 (by rlibby):

Revert r322418, LDBL_MAX_EXP unsuitable for macro pasting on some arches

Either need a different way to spell HALF_LDBL_MAX, or a different way
to spell LDBL_MAX_EXP, or a different approach.

Reported by: ian

MFC r322921 (by ngie):

Revert r321457

It doesn't fail after ^/head@r322855 (the releng_50 clang merge).

PR: 220989

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Merge the projects/release-pkg branch to head.

This allows packaging the base system with pkg(8), including
but not limited to providing the ability to provide upstream
binary update possibilities for non-tier-1 architectures.

This merge is a requirement of the 11.0-RELEASE, and as such,
thank you to everyone that has tested the project branch.

Documentation in build(7) etc. is still somewhat sparse, but
updates to those parts will follow.

Sponsored by: The FreeBSD Foundation

Don't override LIB*DIR variables from src.libnames.mk.

In some cases switch to the LIB*SRCDIR value.

These recently were defined in r291327 and r291619.

Sponsored by: EMC / Isilon Storage Division

Document powl(3)

PR: 191751
Sponsored by: EMC / Isilon Storage Division

Revert r284417 it is not necessary anymore

Enforce overwritting SHLIBDIR

Since METAMODE has been added, sys.mk loads bsd.mkopt.mk which ends load loading
bsd.own.mk which then defines SHLIBDIR before all the Makefile.inc everywhere.

This makes /lib being populated again.

Reported by: many

Misc fixes from projects/bmake

Differential Revision: D2748
Reviewed by: brooks imp

Build/install libc, librt, libthr, and msun NetBSD test suites on all
architectures

MFC after: 1 week

Add reachover Makefiles for contrib/netbsd-tests/lib/librt

A variant of this code has been tested on amd64/i386 for some time by
EMC/Isilon on 10-STABLE/11-CURRENT. It builds on other architectures, but the
code will remain off until it's proven it works on virtual hardware or real
hardware on other architectures

Sponsored by: EMC / Isilon Storage Division

* Makefile:
. Hook e_lgammal[_r].c to the build.
. Create man page links for lgammal[-r].3.

* Symbol.map:
. Sort lgammal to its rightful place.
. Add FBSD_1.4 section for the new lgamal_r symbol.

* ld128/e_lgammal_r.c:
. 128-bit implementataion of lgammal_r().

* ld80/e_lgammal_r.c:
. Intel 80-bit format implementation of lgammal_r().

* src/e_lgamma.c:
. Expose lgammal as a weak reference to lgamma for platforms
where long double is mapped to double.

* src/e_lgamma_r.c:
. Use integer literal constants instead of real literal constants.
Let compiler(s) do the job of conversion to the appropriate type.
. Expose lgammal_r as a weak reference to lgamma_r for platforms
where long double is mapped to double.

* src/e_lgammaf_r.c:
. Fixed the Cygnus Support conversion of e_lgamma_r.c to float.
This includes the generation of new polynomial and rational
approximations with fewer terms. For each approximation, include
a comment on an estimate of the accuracy over the relevant domain.
. Use integer literal constants instead of real literal constants.
Let compiler(s) do the job of conversion to the appropriate type.
This allows the removal of several explicit casts of double values
to float.

* src/e_lgammal.c:
. Wrapper for lgammal() about lgammal_r().

* src/imprecise.c:
. Remove the lgamma.

* src/math.h:
. Add a prototype for lgammal_r().

* man/lgamma.3:
. Document the new functions.

Reviewed by: bde

* Makefile:
. Add s_erfl.c to building libm.
. Add MLINKS for erfl.3 and erfcl.3.

* Symbol.map:
. Move erfl and erfcl to their proper location.

* ld128/s_erfl.c:
. Implementations of erfl and erfcl in the IEEE 754 128-bit format.

* ld80/s_erfl.c:
. Implementations of erfl and erfcl in the Intel 80-bit format.

* man/erf.3:
. Document the new functions.
. While here, remove an incomplete sentence.

* src/imprecise.c:
. Remove the stupidity of mapping erfl and erfcl to erf and erfc.

* src/math.h:
. Move the declarations of erfl and erfcl to their proper place.

* src/s_erf.c:
. For architectures where double and long double are the same
floating point format, use weak references to map erfl to
erf and ercl to erfc.

Reviewed by: bde (many earlier versions)

Merge the projects/clang-sparc64 branch back to head. This brings in
several updates from the llvm and clang trunks to make the sparc64
backend fully functional.

Apart from one patch to sys/sparc64/include/pcpu.h which is still under
discussion, this makes it possible to let clang fully build world and
kernel for sparc64.

Any assistance with testing this on actual sparc64 hardware is greatly
appreciated, as there will unavoidably be bugs left.

Many thanks go to Roman Divacky for his upstream work on getting the
sparc64 backend into shape.

MFC after: 1 month

* Makefile:
. Hook coshl, sinhl, and tanhl into libm.
. Create symbolic links for corresponding manpages.
. While here remove a nearby extraneous space.

* Symbol.map:
* src/math.h:
. Move coshl, sinhl, and tanhl to their proper locations.

* man/cosh.3:
* man/sinh.3:
* man/tanh.3:
. Update the manpages.

* src/e_cosh.c:
* src/e_sinh.c:
* src/s_tanh.c:
. Add weak reference for LBDL_MANT_DIG==53 targets.

* src/imprecise.c:
. Remove the coshl, sinhl, and tanhl kludge.

* src/e_coshl.c:
. ld80 and ld128 implementation of coshl().

* src/e_sinhl.c:
. ld80 and ld128 implementation of sinhl().

* src/s_tanhl.c:
. ld80 and ld128 implementation of tanhl().

Obtained from: bde (mostly), das and kargl

Fix bulding libm on platforms with LDBL_MANT_DIG == 53.

Reported by: ian

Add stub implementations of the missing C++11 math functions.
These are weak and so can be replaced by other versions in applications
that choose to do so, and will give a linker warning when used so that
applications that rely on the extra precision can avoid them.

Note that since the C/C++ specs only guarantee that long double has
precision equal to double, code that actually relies on these functions
having greater precision is unportable at best and broken at worst.

Add implementations of acoshl(), asinhl(), and atanhl(). This is a
merge of the work done by bde and myself.

Style fixes.

Submitted by: bde

Add man links for expl(3) and expm1l(3).

Add logl, log2l, log10l, and log1pl.

Submitted by: bde

I'm happy to finally commit stephen@'s implementations of cacos,
cacosh, casin, casinh, catan, and catanh. Thanks to stephen@ and bde@
for working on these.

Submitted by: stephen@
Reviewed by: bde

Fix some regressions caused by the switch from gcc to clang. The fixes
are workarounds for various symptoms of the problem described in clang
bugs 3929, 8100, 8241, 10409, and 12958.

The regression tests did their job: they failed, someone brought it
up on the mailing lists, and then the issue got ignored for 6 months.
Oops. There may still be some regressions for functions we don't have
test coverage for yet.

Merge the 386 and amd64 versions of the fenv.h, to make cc -m32
compilations which use fenv.h work.

Reviewed by: tjil
Sponsored by: The FreeBSD Foundation

Hook ld80/s_expl.c or ld128/s_expl.c into the building of libm.

PR: standards/152415
Approved by: das (mentor)

Add an implementation of fenv.h intended for platforms that lack an FPU and
use softfloat.

Thanks to Ian Lepore for testing and debugging this patch. The fenv
regression tests pass (at least for Ian's arm chip) with this change.

The cexp() and {,c}{cos,sin}h functions all need to be able to compute
exp(x) scaled down by some factor, and the challenge is doing this
accurately when exp(x) would overflow. This change replaces all of
the tricks we've been using with common __ldexp_exp() and
__ldexp_cexp() routines that handle all the scaling.

bde plans to improve on this further by moving the guts of exp() into
k_exp.c and handling the scaling in a more direct manner. But the
current approach is simple and adequate for now.

Add c{cos,sin,tan}{,h}{,f} functions. This is joint work with
bde and kargl.

Take two. Add the missing file that should have been committed
with r219571 and re-enable building of cbrtl.

Implement the long double version for the cube root function, cbrtl.
The algorithm uses Newton's iterations with a crude estimate of the
cube root to converge to a result.

Reviewed by: bde
Approved by: das

Temporary disable the building of cbrtl until I
can determine why svn will not allow one to commit
a new file.

Approved by: das (implicit)

Implement the long double version for the cube root function, cbrtl.
The algorithm uses Newton's iterations with a crude estimate of the
cube root to converge to a result.

Reviewed by: bde
Approved by: das

Add cexp() and cexpf().

Reviewed by: bde (earlier version)

Add complex(3) manual page documenting our partial support for C99
complex arithmetic in libm.

Reviewed by: David Schultz <das@FreeBSD.org>
MFC after: 2 weeks

Add log2() and log2f().

Disable gcc's built-in rint() function when compiling s_nearbyint.c.
It results in incorrect optimizations that break nearbyint().

PR: 143358
Reviewed by: bde

This is exactly the same as the .else, so remove it.

MFtbemd: Move to using MACHINE_CPUARCH, now that it is safe.

Repair some build breakage introduced in r211725 and garbage collect some
code made obsolete in the same commit.

MFtbemd:

Prefer MACHNE_CPUARCH to MACHINE_ARCH in most contexts where you want
to test of all the CPUs of a given family conform.

powerpc64 floating-point is identical to powerpc, so use the same
code on both architectures.

Implement cproj{,f,l}().

Add implementations of acosl(), asinl(), atanl(), atan2l(),
and cargl().

Reviewed by: bde
sparc64 testing resources from: remko

Set WARNS=1.

I believe I've committed all the bits necessary to make this compile
on all supported architectures. :crosses fingers:

Sort the .PATH entries to give a more reasonable order of precedence:
1. architecture-specific files
2. long double format-specific files
3. bsdsrc
4. src
5. man
The original order was virtually the opposite of this.

This should not cause any functional changes at this time. The
difference is only significant when one wants to override, say, a
generic foo.c with a more specialized foo.c (as opposed to foo.S).

Implement fmodl.
Document fmodl and fix some errors in the fmod manpage.

Hook remquol() and remainderl() up to the build.

Implement csqrtl().

Hook hypotl() and cabsl() up to the build.

Hook up sqrtl() to the build.

Add tgammaf() as a simple wrapper around tgamma().

Hook up sinl(), cosl(), and tanl() to the build.

On arches where long double is the same as double, alias ceil(), floor()
and trunc() to the corresponding long double functions. This is not
just an optimization for these arches. The full long double functions
have a wrong value for `huge', and the arches without full long doubles
depended on it being wrong.

Hook up exp2l() and related docs to the build.

Implement rintl(), nearbyintl(), lrintl(), and llrintl().
Thanks to bde@ for feedback and testing of rintl().

Oops, the previous commit was not needed -- the file was committed but
not checked out due to my checkout error.

Don't try to build s_nanl.c before it is committed.

Add logbl(3) to libm.

Implement and document nan(), nanf(), and nanl(). This commit
adds two new directories in msun: ld80 and ld128. These are for
long double functions specific to the 80-bit long double format
used on x86-derived architectures, and the 128-bit format used on
sparc64, respectively.

Implement and document csqrt(3) and csqrtf(3).

Implement carg(3) and cargf(3).

Rotting in an old src tree since: March 2005

Bump library versions in preparation for 7.0.

Ok'd by: kan

Enable symbol versioning by default. Use WITHOUT_SYMVER to disable it.
Warning, after symbol versioning is enabled, going back is not easy
(use WITHOUT_SYMVER at your own risk).

Change the default thread library to libthr.

There most likely still needs to be a version bump for at least the
thread libraries. If necessary, this will happen later.

Implement modfl().

Add symbol versioning to libm.

Detach k_rem_pio2f.c from the build since it is now unused. It is a libm
internal so this shouldn't cause version problems.

The logb() functions are not just ieee754 "test" functions, but are
standard in C99 and POSIX.1-2001+. They are also not deprecated, since
apart from being standard they can handle special args slightly better
than the ilogb() functions.

Move their documentation to ilogb.3. Try to use consistent and improved
wording for both sets of functions. All of ieee854, C99 and POSIX
have better wording and more details for special args.

Add history for the logb() functions and ilogbl(). Fix history for
ilogb().

Bump the shared library version number of all libraries that have not
been bumped since RELENG_5.

Reviewed by: ru
Approved by: re (not needed for commit check but in principle...)

Fix truncl.3 MLINKS

Implement truncl() based on floorl().

Add roundl(), lroundl(), and llroundl().

Build exp2(), exp2f(), and related documentation.

Implement and document remquo() and remquof().

Document feenableexcept(), fedisableexcept(), and fegetexcept().

- Remove s_ldexpf.c (now aliased to scalbn.)
- Add nexttoward{,f,l} and nextafterl. On all platforms,
nexttowardl is an alias for nextafterl.
- Add fmal.
- Add man pages for new routines: fmal, nextafterl,
nexttoward{,f,l}, scalb{,l}nl.

Note that on platforms where long double is the same as double, we
generally just alias the double versions of the routines, since doing
so avoids extra work on the source code level and redundant code in
the binary. In particular:

ldbl53 ldbl64/113
fmal s_fma.c s_fmal.c
ldexpl s_scalbn.c s_scalbnl.c
nextafterl s_nextafter.c s_nextafterl.c
nexttoward s_nextafter.c s_nexttoward.c
nexttowardf s_nexttowardf.c s_nexttowardf.c
nexttowardl s_nextafter.c s_nextafterl.c
scalbnl s_scalbn.c s_scalbnl.c

Un-document the non-extant exp10() and exp10f() functions.
exp10() was a casualty of the transition away from the VAX.

Remove another vestige of support for a non-IEEE libm.

Move machine-dependent crud to its own makefile.

Remove wrappers and other cruft intended to support SVID, mistakes in
C90, and other arcana. Most of these features were never fully
supported or enabled by default.

Ok: bde, stefanf

- Move the functions presently described in in ieee(3) to their own
manpages. They are not very related, so separating them makes it
easier to add meaningful cross-references and extend some of the
descriptions.
- Move the part of math(3) that discusses IEEE 754 to the ieee(3)
manpage.

Add fma() and fmaf(), which implement a fused multiply-add operation.

amd64 assembly versions of sqrt(), lrint(), and llrint() using SSE2.

Import the subset of J.T. Conklin's single-precision x86-optimized
math routines that appear to be (a) correct and (b) faster than their
MI counterparts on my Pentium 4.

Obtained from: NetBSD

Implement and document ceill().

Hook up and document floorl().

Add MI implementations of [l]lrint[f]() and [l]lround[f]().

Discussed with: bde

Add and document ilogbl(), a long double version of ilogb().

Bump the library version numbers for the following libraries:

/lib/{libm,libreadline}
/usr/lib/{libhistory,libopie,libpcap}

in preparation for doing the same thing to RELENG_5. HUGE amounts of
help for determining what to bump provided by kris.

Discussed on: freebsd-current
Approved by: re (not required for commit but something like this should be)

Add man pages for the cimag(), conj() and creal() functions.

Replace s_isnan.c and s_isnanf.c with the more compact s_isnan.c from
libc. The externally-visible effect of this is to add __isnanl() to
libm, which means that libm.so.2 can once again link against libc.so.4
when LD_BIND_NOW is set. This was broken by the addition of fdiml(),
which calls __isnanl().

Fix two bugs in the signbit() macro, which was implemented last year:

- It was added to libc instead of libm. Hopefully no programs rely
on this mistake.

- It didn't work properly on large long doubles because its argument
was converted to type double, resulting in undefined behavior.

Implement the classification macros isfinite(), isinf(), isnan(), and
isnormal() the hard way, rather than relying on fpclassify(). This is
a lose in the sense that we need a total of 12 functions, but it is
necessary for binary compatibility because we have never bumped libm's
major version number. In particular, isinf(), isnan(), and isnanf()
were BSD libc functions before they were C99 macros, so we can't
reimplement them in terms of fpclassify() without adding a dependency
on libc.so.5. I have tried to arrange things so that programs that
could be compiled in FreeBSD 4.X will generate the same external
references when compiled in 5.X. At the same time, the new macros
should remain C99-compliant.

The isinf() and isnan() functions remain in libc for historical
reasons; however, I have moved the functions that implement the macros
isfinite() and isnormal() to libm where they belong. Moreover,
half a dozen MD versions of isinf() and isnan() have been replaced
with MI versions that work equally well.

Prodded by: kris

Add C99's nearbyint{,f}() functions as wrappers around rint().
These trivial implementations are about 25 times slower than
rint{,f}() on x86 due to the FP environment save/restore.
They should eventually be redone in terms of fegetround() and
bit fiddling.

Implement and document fdim{,f,l}, fmax{,f,l}, and fmin{,f,l}.

s/ARCH/ARCH_SUBDIR/g -- This reduces the chance of possible conflicts
with the user's environment.

Wondered why his cross-builds kept failing: marcel

Completely remove s_ilogb.S as the assembler implementation gives very little
speed improvement to none at all over the MI version.

Submitted by: bde

Connect scalbln(), trunc(), and the associated documentation to the build.

Add round(3) and roundf(3) and the associated documentation.

PR: 59797
Submitted by: "Steven G. Kargl" <kargl@troutmask.apl.washington.edu>
Reviewed by: bde (earlier version, last year)

Add fenv.h, fenv.c, and the associated documentation to the libm
build. To facilitate this, add ${.CURDIR}/${ARCH} to make's search
path unconditionally.

Reviewed by: standards@

Add implementations for cimag{,f,l}, creal{,f,l} and conj{,f,l}. They are
needed for cases where GCC's builtin functions cannot be used and for
compilers that don't know about them.

Approved by: das (mentor)

Add an implementation of copysignl(), a long double version of copysign().

Approved by: das (mentor)

Add an MLINK for fabsl().

Approved by: das (mentor)

- fabsl.c should be named s_fabsl.c for consistency with libmsun's
documented naming scheme (unfortunately the documentation isn't in the
tree as far as I can tell); no repocopy is required as there is no
history to preserve.

- replace simple and almost-correct implementation with slightly hackish
but definitely correct implementation (tested on i386, alpha, sparc64)
which requires pulling in fpmath.h and the MD _fpmath.h from libc.

- try not to make a mess of the Makefile in the process.

- enterprising minds are encouraged to implement more C99 long double
functions.

Connect fabsl.c to the build.

Stage 3 of dynamic root support. Make all the libraries needed to run
binaries in /bin and /sbin installed in /lib. Only the versioned files
reside in /lib, the .so symlink continues to live /usr/lib so the
toolchain doesn't need to be modified.

Fixed some style bugs (misplacement and misformatting of some commented-out
code).

Only provide one copy of the math functions. If we provide a MD function,
do not also provide a __generic_XXX version as well. This is how we
used to runtime select the generic vs i387 versions on the i386 platform.

This saves a pile of #defines in the src/math_private.h file to undo the
__generic_XXX renames in some of the *.c files.

No longer need the internal __get_hw_float() function.

Now that we do not need to do runtime detection for the broken default
fp emulator, stop doing the runtime selection of hardware or emulated
floating point operations on i386. Note that I have not suppressed the
duplicate compiles yet.

While here, fix the alpha. It has provided specific copysign/copysignf
functions since the beginning of time, but they have never been used.

Added new bsd.incs.mk which handles installing of header files
via INCS. Implemented INCSLINKS (equivalent to SYMLINKS) to
handle symlinking include files. Allow for multiple groups of
include files to be installed, with the powerful INCSGROUPS knob.
Documentation to follow.

Added standard `includes' and `incsinstall' targets, use them
in Makefile.inc1. Headers from the following makefiles were
not installed before (during `includes' in Makefile.inc1):

kerberos5/lib/libtelnet/Makefile
lib/libbz2/Makefile
lib/libdevinfo/Makefile
lib/libform/Makefile
lib/libisc/Makefile
lib/libmenu/Makefile
lib/libmilter/Makefile
lib/libpanel/Makefile

Replaced all `beforeinstall' targets for installing includes
with the INCS stuff.

Renamed INCDIR to INCSDIR, for consistency with FILES and SCRIPTS,
and for compatibility with NetBSD. Similarly for INCOWN, INCGRP,
and INCMODE.

Consistently use INCLUDEDIR instead of /usr/include.

gnu/lib/libstdc++/Makefile and gnu/lib/libsupc++/Makefile changes
were only lightly tested due to the missing contrib/libstdc++-v3.
I fully tested the pre-WIP_GCC31 version of this patch with the
contrib/libstdc++.295 stuff.

These changes have been tested on i386 with the -DNO_WERROR "make
world" and "make release".

Resurrect Lite1's gamma() as C99's tgamma(). Minimal changes.

We need an frexp() function.

* remove reference to m68k-dependent sources
* fix comment

Don't install manpage links for the nonexistent functions exp2(),
exp2f(), log2() and log2f().

MAN[1-9] -> MAN.

Don't use MANDEPEND and MANSRC.

$Id$ -> $FreeBSD$

Disable building with alpha software completion options until we upgrade
compilers.

Implement fpsetmask() and other fp*() functions. Programs should use

#include <ieeefp.h>

to access these functions instead of the i386 specific

#include <machine/floatingpoint.h>

Submitted by: Hidetoshi Shimokawa <simokawa@sat.t.u-tokyo.ac.jp>

Add alpha support. m68k crept in too. Oops. 8-)

Added -D_ARCH_INDIRECT=i387_ to CFLAGS. _ARCH_INDIRECT will soon be used
to control generation of indirections in ENTRY(). Only msun needs it.

Use ${ARCH} consistently.

Revert $FreeBSD$ to $Id$

Split up the Bessel function wrapper files so that most wrapper functions
are in their own file.

Select between the generic math functions and the i387-specific ones
at runtime.

etc/make.conf:
Nuked HAVE_FPU option.

lib/msun/Makefile:
Always build the i387 objects. Copy the i387 source files at build
time so that the i387 objects have different names. This is simpler
than renaming the files in the cvs repository or repeating half of
bsd.lib.mk to add explicit rules.

lib/msun/src/*.c:
Renamed all functions that have an i387-specific version by adding
`__generic_' to their names.

lib/msun/src/get_hw_float.c:
New file for getting machdep.hw_float from the kernel.

sys/i386/include/asmacros.h:
Abuse the ENTRY() macro to generate jump vectors and associated code.
This works much like PIC PLT dynamic initialization. The PIC case is
messy. The old i387 entry points are renamed. Renaming is easier
here because the names are given by macro expansions.

Put back .endif clobbered by the previous commit, breaking the
build.

Disabled the i387 version if log1p(). It just evaluates log(1 + x).
This defeats the point of log1p(). ucbtest reports errors of +-5e+15
ULPs. A correct version would use the i387 fyl2xp1 instruction for
small x and maybe scale to small x. The C version does the scaling
reasonably efficiently, and fyl2px1 is slow (at least on P5s), so not
much is lost by always using the C version (only 25% for small x even
with the broken i387 version; 50% for large x).

Make the long-awaited change from $Id$ to $FreeBSD$

This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.

Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.

Delete -D_POSIX_MODE and -D_MULTI_LIBM from CFLAGS. They never had any effect
because _IEEE_LIBM always takes priority, so the definition just served
to confuse.

Reviewed by: bde

consistancy fixup

Submitted by: "Philippe Charnier" <charnier@xp11.frmug.org>

cmp -s || install -c ==> install -C

Correct one small typo in previous commit.

Added some missing MLINKS for section 3 man pages.
Also corrected a few minor formatting errors, file location and cross
references in some of the section 3 man pages.

This shuts up a lot of the output from "manck" for section 3.

Undo the the changes in the previous revision (MANSRC now works right again).
Use ${INSTALL} instead of install.

Compress manual pages (if desired) in the obj directory rather
than in the installation destination. Should make release-building
substantially faster. The msun Makefile changes simple adapt to the new
scheme.

Remove trailing whitespace.

Obtained from: NetBSD

Remove common sources from ${SRCS} when they are replaced by arch-specific
sources.

Install math.h.

Make this puppy actually compile now.
Submitted by: jkh

This commit was generated by cvs2svn to compensate for changes in r2116,
which included commits to RCS files with non-trunk default branches.

J.T. Conklin's latest version of the Sun math library.

-- Begin comments from J.T. Conklin:
The most significant improvement is the addition of "float" versions
of the math functions that take float arguments, return floats, and do
all operations in floating point. This doesn't help (performance)
much on the i386, but they are still nice to have.

The float versions were orginally done by Cygnus' Ian Taylor when
fdlibm was integrated into the libm we support for embedded systems.
I gave Ian a copy of my libm as a starting point since I had already
fixed a lot of bugs & problems in Sun's original code. After he was
done, I cleaned it up a bit and integrated the changes back into my
libm.
-- End comments

Reviewed by: jkh
Submitted by: jtc