Commit Graph

1102 Commits

Author SHA1 Message Date
Paul E. Murphy
f6d3a72eca Prepare to convert _Complex tangent functions
This patch has no function changes, except to
ensure the git history correctly tracks the
changes to convert the double version of these
functions into a templated version.
2016-08-19 16:47:14 -05:00
Paul E. Murphy
c50eee19c4 Convert _Complex sine functions to generated code
Refactor s_c{,a}sin{,h}{f,,l} into a single templated
macro.
2016-08-19 16:46:41 -05:00
Paul E. Murphy
ffb84f5e19 Prepare to convert _Complex sine functions
This patch has no function changes, except to
ensure the git history correctly tracks the
changes to convert the double version of these
functions into a templated version.
2016-08-19 16:12:36 -05:00
Paul E. Murphy
4482ff226e Merge common usage of mul_split function
A number of files share identical code for the
mul_split function.

This moves the duplicated function mul_split into its
own header, and refactors the fma usage into a single
selection macro.  Likewise, mul_split when used by a
long double implementation is renamed mul_splitl for
clarity.
2016-08-19 11:29:43 -05:00
Paul E. Murphy
01ee387015 Convert _Complex cosine functions to generated code
This is fairly straight fowards.  m68k overrides are
updated to use the framework, and thus are simplified
a bit.
2016-08-19 11:28:55 -05:00
Paul E. Murphy
281f5073e5 Prepare to convert _Complex cosine functions
This patch has no function changes, except to
ensure the git history correctly tracks the
changes to convert the double version of these
functions into a templated version.
2016-08-19 11:28:17 -05:00
Paul E. Murphy
ce6698ea0a Support for type-generic libm function implementations libm
This defines a new classes of libm objects.  The
<func>_template.c file which is used in conjunction
with the new makefile hooks to derive variants for
each type supported by the target machine.

The headers math-type-macros-TYPE.h are used to supply
macros to a common implementation of a function in
a file named FUNC_template.c and glued togethor via
a generated file matching existing naming in the
build directory.

This has the properties of preserving the existing
override mechanism and not requiring any arcane
build system twiddling.  Likewise, it enables machines
to override these files without any additional work.

I have verified the built objects for ppc64, x86_64,
alpha, arm, and m68k do not change in any meaningful
way with these changes using the Fedora cross toolchains.
I have verified the x86_64 and ppc64 changes still run.
2016-08-17 14:06:03 -05:00
Joseph Myers
5146356f5a Add fesetexcept.
TS 18661-1 defines an fesetexcept function for setting floating-point
exception flags without the side-effect of causing enabled traps to be
taken.

This patch series implements this function for glibc.  The present
patch adds the fallback stub implementation, x86 and x86_64
implementations, documentation, tests and ABI baseline updates.  The
remaining patches, some of them untested, add implementations for
other architectures.  The implementations generally follow those of
the fesetexceptflag function.

As for fesetexceptflag, the approach taken for architectures where
setting flags causes enabled traps to be taken is to set the flags
(and potentially cause traps) rather than refusing to set the flags
and returning an error.  Since ISO C and TS 18661 provide no way to
enable traps, this is formally in accordance with the standards.

The NEWS entry should be considered a placeholder, since this patch
series is intended to be followed by further such series adding other
TS 18661-1 features, so that the NEWS entry would end up looking more
like

* New <fenv.h> features from TS 18661-1:2014 are added to libm: the
  fesetexcept, fetestexceptflag, fegetmode and fesetmode functions,
  the femode_t type and the FE_DFL_MODE macro.

with hopefully more such entries for other features, rather than
having an entry for a single function in the end.

I believe we have consensus for adding TS 18661-1 interfaces as per
<https://sourceware.org/ml/libc-alpha/2016-06/msg00421.html>.

Tested for x86_64, x86, mips64 (hard float, and soft float to test the
fallback version), arm (hard float) and powerpc (hard float, soft
float and e500).

	* math/fesetexcept.c: New file.
	* sysdeps/i386/fpu/fesetexcept.c: Likewise.
	* sysdeps/x86_64/fpu/fesetexcept.c: Likewise.
	* math/fenv.h: Define
	__GLIBC_INTERNAL_STARTING_HEADER_IMPLEMENTATION and include
	<bits/libc-header-start.h> instead of including <features.h>.
	[__GLIBC_USE (IEC_60559_BFP_EXT)] (fesetexcept): New function
	declaration.
	* manual/arith.texi (fesetexcept): Document function.
	* math/Versions (fesetexcept): New libm symbol at version
	GLIBC_2.25.
	* math/Makefile (libm-support): Add fesetexcept.
	(tests): Add test-fesetexcept and test-fesetexcept-traps.
	* math/test-fesetexcept.c: New file.
	* math/test-fesetexcept-traps.c: Likewise.
	* sysdeps/nacl/libm.abilist: Update.
	* sysdeps/unix/sysv/linux/aarch64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/alpha/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/arm/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/hppa/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/i386/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/ia64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/m68k/coldfire/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/m68k/m680x0/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/microblaze/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/mips/mips32/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/mips/mips64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/nios2/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libm.abilist:
	Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libm.abilist:
	Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/libm-le.abilist:
	Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/libm.abilist:
	Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/sh/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libm.abilist:
	Likewise.
	* sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libm.abilist:
	Likewise.
	* sysdeps/unix/sysv/linux/tile/tilepro/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/x32/libm.abilist: Likewise.
2016-08-16 16:16:10 +00:00
Joseph Myers
98dac0ce76 Fix test-fexcept when "inexact" implicitly raised.
ISO C allows feraiseexcept to raise "inexact", in addition to the
requested exceptions, when requested to raise "overflow" or
"underflow".  Testing on ARM and PowerPC e500 (where glibc's
feraiseexcept has this property) showed that the new test-fexcept test
failed to allow for this; this patch fixes it, by wrapping
feraiseexcept to clear FE_INEXACT if implicitly raised and not raised
before the call.  (It would also be possible to do this with
fesetexcept, which always affects exactly the requested flags, but
this patch avoids making this fix depend on the fesetexcept changes.)

Tested for x86_64, x86, arm and e500.

	* math/test-fexcept.c (feraiseexcept_exact): New function.
	(test_set): Call feraiseexcept_exact instead of feraiseexcept.
	(test_except): Likewise.
2016-08-12 17:34:01 +00:00
Joseph Myers
5220a1aa8d Add tests for fegetexceptflag, fesetexceptflag.
I noticed that there was no meaningful test coverage for
fegetexceptflag and fesetexceptflag (one test ensures that calls to
them compile and link, but nothing to verify they work correctly).
This patch adds tests for these functions.

fesetexceptflag is meant to set the relevant exception flag bits to
the saved state without causing enabled traps to be taken.  On some
architectures, it is not possible to set exception flag bits without
causing enabled traps to occur.  Such architectures need to define
EXCEPTION_SET_FORCES_TRAP to 1 in their math-tests.h, as is done in
this patch for powerpc.  x86 avoids needing to define this because the
traps resulting from setting exception bits don't occur until the next
floating-point operation or fwait instruction.

Tested for x86_64, x86 and powerpc.  Note that test-fexcept fails for
powerpc because of a pre-existing bug in fesetexceptflag for powerpc,
which I'll fix separately.

	* math/test-fexcept-traps.c: New file.
	* math/test-fexcept.c: Likewise.
	* math/Makefile (tests): Add test-fexcept and test-fexcept-traps.
	* sysdeps/generic/math-tests.h (EXCEPTION_SET_FORCES_TRAP): New
	macro.
	* sysdeps/powerpc/math-tests.h [!__NO_FPRS__]
	(EXCEPTION_SET_FORCES_TRAP): Likewise.
2016-08-10 21:01:08 +00:00
Aurelien Jarno
bf79a337ec sparc32/sparcv9: add a VIS3 version of fdim
sparc32 passes floating point values in the integer registers. VIS3
instructions gives access to the movwtos instruction to directly
transfer a value from an integer register to a floating point register.
Therefore it makes sense to provide a VIS3 version consisting in the
generic version compiled with -mvis3.

Changelog:
	* math/s_fdim.c: Avoid alias renamed.
	* math/s_fdimf.c: Likewise.
	* sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/Makefile
	[$(subdir) = math && $(have-as-vis3) = yes] (libm-sysdep_routines):
	Add s_fdimf-vis3, s_fdim-vis3.
	(CFLAGS-s_fdimf-vis3.c): New. Set to -Wa,-Av9d -mvis3.
	(CFLAGS-s_fdim-vis3.c): Likewise.
	sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fdim-vis3.c: New file.
	sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fdim.c: Likewise.
2016-08-05 22:35:01 +02:00
Paul E. Murphy
d4cf133100 Improve gen-libm-test.pl LIT() application
When bootstrapping float128, this exposed a number of areas where
the L suffix is incorrectly applied to simple expressions when it
should be applied to each constant in the expression.

In order to stave off more macros in libm-test.inc, apply_lit is
made slightly more intelligent.  It will now split expressions
based on space characters, and attempt to apply LIT() to each
token.

Having done this, there are numerous spacing issues within
libm-test.inc which have been fixed.

The above is problematic when the L real suffix is not the most
expressive modifier, and the compiler complains (i.e ppc64) or
silently truncates a value (i.e ppc64).
2016-08-05 14:38:57 -05:00
Joseph Myers
89a12e6f8e Fix math.h comment about bits/mathdef.h.
math.h has a comment about definitions from <bits/mathdef.h>.  This
comment is in the wrong place in math.h, far below the inclusion of
<bits/mathdef.h>.  It was originally above the inclusion, but the
inclusion was moved by

1998-11-05  Ulrich Drepper  <drepper@cygnus.com>

        * math/math.h: Unconditionally include bits/mathdef.h.  Declare
        long double functions only if __NO_LONG_DOUBLE_MATH is not
        defined.
        [...]

without moving the comment.  Furthermore, the comment refers
incorrectly to FLT_EVAL_METHOD and DECIMAL_DIG, which are actually
<float.h> macros, and INFINITY, which is in <bits/inf.h>.

This patch moves the comment back above the include it refers to and
removes the description of macros not defined by the header.

Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by the patch).

	* math/math.h: Move comment about <bits/mathdef.h> definitions
	above inclusion of <bits/mathdef.h>.  Do not mention
	FLT_EVAL_METHOD, INFINITY or DECIMAL_DIG in that comment.
2016-08-05 18:15:00 +00:00
Joseph Myers
cb864fe0ec Do not call __nan in scalb functions.
When libm functions return a NaN: if it is for NaN input, it should be
computed from that input (e.g. adding it to itself), so that payloads
are propagated and signaling NaNs quieted, while if it is for non-NaN
input, it should be produced by a computation such as
(x - x) / (x - x), which raises "invalid" at the same time as
producing an appropriate NaN, so avoiding any need for a call to
feraiseexcept.

Various libm functions, however, call __nan ("") (or __nanf or __nanl)
to determine the NaN to return, together with using feraiseexcept
(FE_INVALID) to raise the exception.  sysdeps/generic/math_private.h
has an optimization for those functions with constant "" argument so
this doesn't actually involve a call to the __nan function, but it is
still not the preferred approach for producing NaNs.  (The optimized
code also always uses the NAN macro, i.e. produces a default NaN for
float converted to whatever the target type is, and on some
architectures that may not be the same as the preferred default NaN
for double or long double.)

This patch fixes the scalb functions to use the conventional method of
generating NaNs and raising "invalid" with an appropriate
computation.  (Most instances of this issue are in the complex
functions, where it can more readily be fixed once they have been made
type-generic and so only a third as many places need fixing.  Some of
the complex functions use __nan ("") + __nan (""), where the addition
serves no purpose whatsoever.)

Tested for x86_64 and x86.

	* math/e_scalb.c: Do not include <fenv.h>.
	(invalid_fn): Do calculation resulting in NaN instead of raising
	FE_INVALID and returning a NaN explicitly.
	* math/e_scalbf.c: Do not include <fenv.h>.
	(invalid_fn): Do calculation resulting in NaN instead of raising
	FE_INVALID and returning a NaN explicitly.
	* math/e_scalbl.c: Do not include <fenv.h>.
	(invalid_fn): Do calculation resulting in NaN instead of raising
	FE_INVALID and returning a NaN explicitly.
2016-08-04 20:50:31 +00:00
Joseph Myers
146f208da6 Also handle __STDC_WANT_IEC_60559_BFP_EXT__ in <tgmath.h>.
My __STDC_WANT_IEC_60559_BFP_EXT__ patch omitted to update the
conditions on the nextup and nextdown type-generic macros in
<tgmath.h>.  This patch updates those conditions accordingly.  (As
glibc doesn't currently have an exp10 type-generic macro, no such
changes are needed relating to __STDC_WANT_IEC_60559_FUNCS_EXT__;
adding such a type-generic macro would be a new feature.)

Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by the patch).  Committed.

	* math/tgmath.h (nextdown): Define if
	[__GLIBC_USE (IEC_60559_BFP_EXT)], not if [__USE_GNU].
	(nextup): Likewise.
2016-08-03 22:56:54 +00:00
Joseph Myers
412cb261b0 Support __STDC_WANT_IEC_60559_FUNCS_EXT__ feature test macro.
This patch implements support for the
__STDC_WANT_IEC_60559_FUNCS_EXT__ feature test macro, following the
__GLIBC_USE approach used for other ISO C feature test macros.
Currently this only affects the exp10 functions (which glibc has had
for a long time).

Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by the patch).

	* bits/libc-header-start.h (__GLIBC_USE_IEC_60559_FUNCS_EXT): New
	macro.
	* include/features.h (__STDC_WANT_IEC_60559_FUNCS_EXT__):
	Document.
	* manual/creature.texi (__STDC_WANT_IEC_60559_FUNCS_EXT__):
	Document macro.
	* manual/math.texi (exp10): Document as ISO from TS 18661-4:2015.
	(exp10f): Likewise.
	(exp10l): Likewise.
	* math/bits/mathcalls.h (exp10): Declare if
	[__GLIBC_USE (IEC_60559_FUNCS_EXT)], not [__USE_GNU].
2016-08-03 22:21:37 +00:00
Joseph Myers
bf91be88ea Support __STDC_WANT_IEC_60559_BFP_EXT__ feature test macro.
This patch implements support for the __STDC_WANT_IEC_60559_BFP_EXT__
feature test macro from ISO/IEC 18661-1:2014, following the
__GLIBC_USE approach now used for __STDC_WANT_LIB_EXT2__.  For this
macro, the relevant consideration is whether it is defined or
undefined when an affected header is included (not what its value is
if defined, and not whether it's defined or undefined when any other
unaffected system header is included).

Currently this macro only affects the issignaling macro and the nextup
and nextdown functions (so they can be enabled by defining this macro,
not just by defining _GNU_SOURCE as previously).  Any further features
from this TS added in future would also be conditioned on this macro.

Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by the patch).

	* bits/libc-header-start.h (__GLIBC_USE_IEC_60559_BFP_EXT): New
	macro.
	* include/features.h (__STDC_WANT_IEC_60559_BFP_EXT__): Document.
	* manual/arith.texi (issignaling): Document as ISO from TS
	18661-1:2014.
	(nextup): Likewise.
	(nextupf): Likewise.
	(nextupl): Likewise.
	(nextdown): Likewise.
	(nextdownf): Likewise.
	(nextdownl): Likewise.
	* manual/creature.texi (__STDC_WANT_IEC_60559_BFP_EXT__): Document
	macro.
	* math/math.h: Define
	__GLIBC_INTERNAL_STARTING_HEADER_IMPLEMENTATION and include
	<bits/libc-header-start.h> instead of including <features.h>.
	(issignaling): Define if [__GLIBC_USE (IEC_60559_BFP_EXT)], not
	[__USE_GNU].
	* math/bits/mathcalls.h (nextdown): Declare if
	[__GLIBC_USE (IEC_60559_BFP_EXT)], not [__USE_GNU].
	(nextup): Likewise.
	(__issignaling): Likewise.
2016-08-03 17:30:41 +00:00
Paul E. Murphy
f2de695bf6 Unify drift between _Complex function type variants
While trying to convert the _Complex function wrappers
into a single generic implementation, a few minor
variations between identical versions emerged.
2016-08-03 11:07:04 -05:00
Paul E. Murphy
b9e05ed07a Refactor part of math Makefile
In order to support more types, the Makefile needs a few bits
shuffled.

F is explictly used as a placeholder to substitute for the
appropriate type suffix.  This removes the need to demangle
_r suffixed objects.

The variable libm-compat-calls is added to house any objects which
are only built to provide compat symbols within libm.  That is,
no newly added type should ever attempt building these.  Note,
k_standard* files have been added there.  By consensus they are
deprecated; in practice, we haven't gotten there yet.

New types would be added as noted in the comments preceding
type-TYPE-{suffix,routines,yes} variables.  However, some manual
additions will still need to be done to add appropriate flags
when building the various variants of libm-test.c for a new type.

Likewise, test-ildoubl is renamed test-ildouble for consistency's
sake.
2016-08-03 11:05:22 -05:00
Andrew Senkevich
533f9bebf9 x86_64: Call finite scalar versions in vectorized log, pow, exp (bz #20033).
Vector math functions require -ffast-math which sets -ffinite-math-only,
so it is needed to call finite scalar versions (which are called from
vector functions in some cases).

Since finite version of pow() returns qNaN instead of 1.0 for several
inputs, those inputs are excluded for tests of vector math functions.

    [BZ #20033]
    * sysdeps/x86_64/fpu/multiarch/svml_d_exp2_core_sse4.S: Call
    finite version.
    * sysdeps/x86_64/fpu/multiarch/svml_d_exp4_core_avx2.S: Likewise.
    * sysdeps/x86_64/fpu/multiarch/svml_d_exp8_core_avx512.S: Likewise.
    * sysdeps/x86_64/fpu/multiarch/svml_d_log2_core_sse4.S: Likewise.
    * sysdeps/x86_64/fpu/multiarch/svml_d_log4_core_avx2.S: Likewise.
    * sysdeps/x86_64/fpu/multiarch/svml_d_log8_core_avx512.S: Likewise.
    * sysdeps/x86_64/fpu/multiarch/svml_d_pow2_core_sse4.S: Likewise.
    * sysdeps/x86_64/fpu/multiarch/svml_d_pow4_core_avx2.S: Likewise.
    * sysdeps/x86_64/fpu/multiarch/svml_d_pow8_core_avx512.S: Likewise.
    * sysdeps/x86_64/fpu/multiarch/svml_s_expf16_core_avx512.S: Likewise.
    * sysdeps/x86_64/fpu/multiarch/svml_s_expf4_core_sse4.S: Likewise.
    * sysdeps/x86_64/fpu/multiarch/svml_s_expf8_core_avx2.S: Likewise.
    * sysdeps/x86_64/fpu/multiarch/svml_s_logf16_core_avx512.S: Likewise.
    * sysdeps/x86_64/fpu/multiarch/svml_s_logf4_core_sse4.S: Likewise.
    * sysdeps/x86_64/fpu/multiarch/svml_s_logf8_core_avx2.S: Likewise.
    * sysdeps/x86_64/fpu/multiarch/svml_s_powf16_core_avx512.S: Likewise.
    * sysdeps/x86_64/fpu/multiarch/svml_s_powf4_core_sse4.S: Likewise.
    * sysdeps/x86_64/fpu/multiarch/svml_s_powf8_core_avx2.S: Likewise.
    * sysdeps/x86_64/fpu/svml_d_exp2_core.S: Likewise.
    * sysdeps/x86_64/fpu/svml_d_log2_core.S: Likewise.
    * sysdeps/x86_64/fpu/svml_d_pow2_core.S: Likewise.
    * sysdeps/x86_64/fpu/svml_s_expf4_core.S: Likewise.
    * sysdeps/x86_64/fpu/svml_s_logf4_core.S: Likewise.
    * sysdeps/x86_64/fpu/svml_s_powf4_core.S: Likewise.
    * math/libm-test.inc (pow_test_data): Exclude tests for qNaN
    in power zero.
2016-08-02 16:35:25 +03:00
Siddhesh Poyarekar
cbf88869ed Fix cos computation for multiple precision fallback (bz #20357)
During the sincos consolidation I made two mistakes, one was a logical
error due to which cos(0x1.8475e5afd4481p+0) returned
sin(0x1.8475e5afd4481p+0) instead.

The second issue was an error in negating inputs for the correct
quadrants for sine.  I could not find a suitable test case for this
despite running a program to search for such an input for a couple of
hours.

Following patch fixes both issues.  Tested on x86_64.  Thanks to Matt
Clay for identifying the issue.

	[BZ #20357]
	* sysdeps/ieee754/dbl-64/s_sin.c (sloww): Fix up condition
	to call __mpsin/__mpcos and to negate values.
	* math/auto-libm-test-in: Add test.
	* math/auto-libm-test-out: Regenerate.
2016-07-18 22:33:09 +05:30
Joseph Myers
30dcf959d2 Avoid "inexact" exceptions in i386/x86_64 trunc functions (bug 15479).
As discussed in
<https://sourceware.org/ml/libc-alpha/2016-05/msg00577.html>, TS
18661-1 disallows ceil, floor, round and trunc functions from raising
the "inexact" exception, in accordance with general IEEE 754 semantics
for when that exception is raised.  Fixing this for x87 floating point
is more complicated than for the other versions of these functions,
because they use the frndint instruction that raises "inexact" and
this can only be avoided by saving and restoring the whole
floating-point environment.

As I noted in
<https://sourceware.org/ml/libc-alpha/2016-06/msg00128.html>, I have
now implemented a GCC option -fno-fp-int-builtin-inexact for GCC 7,
such that GCC will inline these functions on x86, without caring about
"inexact", when the default -ffp-int-builtin-inexact is in effect.
This allows users to get optimized code depending on the options they
pass to the compiler, while making the out-of-line functions follow TS
18661-1 semantics and avoid "inexact".

This patch duly fixes the out-of-line trunc function implementations
to avoid "inexact", in the same way as the nearbyint implementations.

I do not know how the performance of implementations such as these
based on saving the environment and changing the rounding mode
temporarily compares to that of the C versions or SSE 4.1 versions (of
course, for 32-bit x86 SSE implementations still need to get the
return value in an x87 register); it's entirely possible other
implementations could be faster in some cases.

Tested for x86_64 and x86.

	[BZ #15479]
	* sysdeps/i386/fpu/s_trunc.S (__trunc): Save and restore
	floating-point environment rather than just control word.
	* sysdeps/i386/fpu/s_truncf.S (__truncf): Likewise.
	* sysdeps/i386/fpu/s_truncl.S (__truncl): Save and restore
	floating-point environment, with "invalid" exceptions merged in,
	rather than just control word.
	* sysdeps/x86_64/fpu/s_truncl.S (__truncl): Likewise.
	* math/libm-test.inc (trunc_test_data): Do not allow spurious
	"inexact" exceptions.
2016-06-27 17:26:52 +00:00
Joseph Myers
623629de06 Avoid "inexact" exceptions in i386/x86_64 floor functions (bug 15479).
As discussed in
<https://sourceware.org/ml/libc-alpha/2016-05/msg00577.html>, TS
18661-1 disallows ceil, floor, round and trunc functions from raising
the "inexact" exception, in accordance with general IEEE 754 semantics
for when that exception is raised.  Fixing this for x87 floating point
is more complicated than for the other versions of these functions,
because they use the frndint instruction that raises "inexact" and
this can only be avoided by saving and restoring the whole
floating-point environment.

As I noted in
<https://sourceware.org/ml/libc-alpha/2016-06/msg00128.html>, I have
now implemented a GCC option -fno-fp-int-builtin-inexact for GCC 7,
such that GCC will inline these functions on x86, without caring about
"inexact", when the default -ffp-int-builtin-inexact is in effect.
This allows users to get optimized code depending on the options they
pass to the compiler, while making the out-of-line functions follow TS
18661-1 semantics and avoid "inexact".

This patch duly fixes the out-of-line floor function implementations
to avoid "inexact", in the same way as the nearbyint implementations.

I do not know how the performance of implementations such as these
based on saving the environment and changing the rounding mode
temporarily compares to that of the C versions or SSE 4.1 versions (of
course, for 32-bit x86 SSE implementations still need to get the
return value in an x87 register); it's entirely possible other
implementations could be faster in some cases.

Tested for x86_64 and x86.

	[BZ #15479]
	* sysdeps/i386/fpu/s_floor.S (__floor): Save and restore
	floating-point environment rather than just control word.
	* sysdeps/i386/fpu/s_floorf.S (__floorf): Likewise.
	* sysdeps/i386/fpu/s_floorl.S (__floorl): Save and restore
	floating-point environment, with "invalid" exceptions merged in,
	rather than just control word.
	* sysdeps/x86_64/fpu/s_floorl.S (__floorl): Likewise.
	* math/libm-test.inc (floor_test_data): Do not allow spurious
	"inexact" exceptions.
2016-06-27 17:25:47 +00:00
Joseph Myers
26b0bf9600 Avoid "inexact" exceptions in i386/x86_64 ceil functions (bug 15479).
As discussed in
<https://sourceware.org/ml/libc-alpha/2016-05/msg00577.html>, TS
18661-1 disallows ceil, floor, round and trunc functions from raising
the "inexact" exception, in accordance with general IEEE 754 semantics
for when that exception is raised.  Fixing this for x87 floating point
is more complicated than for the other versions of these functions,
because they use the frndint instruction that raises "inexact" and
this can only be avoided by saving and restoring the whole
floating-point environment.

As I noted in
<https://sourceware.org/ml/libc-alpha/2016-06/msg00128.html>, I have
now implemented a GCC option -fno-fp-int-builtin-inexact for GCC 7,
such that GCC will inline these functions on x86, without caring about
"inexact", when the default -ffp-int-builtin-inexact is in effect.
This allows users to get optimized code depending on the options they
pass to the compiler, while making the out-of-line functions follow TS
18661-1 semantics and avoid "inexact".

This patch duly fixes the out-of-line ceil function implementations to
avoid "inexact", in the same way as the nearbyint implementations.

I do not know how the performance of implementations such as these
based on saving the environment and changing the rounding mode
temporarily compares to that of the C versions or SSE 4.1 versions (of
course, for 32-bit x86 SSE implementations still need to get the
return value in an x87 register); it's entirely possible other
implementations could be faster in some cases.

Tested for x86_64 and x86.

	[BZ #15479]
	* sysdeps/i386/fpu/s_ceil.S (__ceil): Save and restore
	floating-point environment rather than just control word.
	* sysdeps/i386/fpu/s_ceilf.S (__ceilf): Likewise.
	* sysdeps/i386/fpu/s_ceill.S (__ceill): Save and restore
	floating-point environment, with "invalid" exceptions merged in,
	rather than just control word.
	* sysdeps/x86_64/fpu/s_ceill.S (__ceill): Likewise.
	* math/libm-test.inc (ceil_test_data): Do not allow spurious
	"inexact" exceptions.
2016-06-27 17:24:30 +00:00
Joseph Myers
40244be372 Fix i386/x86_64 scalbl with sNaN input (bug 20296).
The x86_64 and i386 versions of scalbl return sNaN for some cases of
sNaN input and are missing "invalid" exceptions for other cases.  This
results from overly complicated code that either returns a NaN input,
or discards both inputs when one is NaN and loads a NaN from memory.
This patch fixes this by simplifying the code to add the arguments
when either one is NaN.

Tested for x86_64 and x86.

	[BZ #20296]
	* sysdeps/i386/fpu/e_scalbl.S (__ieee754_scalbl): Add arguments
	when either argument is a NaN.
	* sysdeps/x86_64/fpu/e_scalbl.S (__ieee754_scalbl): Likewise.
	* math/libm-test.inc (scalb_test_data): Add sNaN tests.
2016-06-23 22:17:41 +00:00
Joseph Myers
7ed84b89f3 Add more sNaN tests (most remaining real functions).
This patch adds tests of sNaN inputs to more functions to
libm-test.inc.  This covers the remaining real functions except for
scalb, where there's a bug to fix, and hypot pow fmin fmax, where
there are cases where a qNaN input does not result in a qNaN output
and so sNaN support according to TS 18661-1 is more of a new feature.

Tested for x86_64 and x86.

	* math/libm-test.inc (snan_value_ld): New macro.
	(isgreater_test_data): Add sNaN tests.
	(isgreaterequal_test_data): Likewise.
	(isless_test_data): Likewise.
	(islessequal_test_data): Likewise.
	(islessgreater_test_data): Likewise.
	(isunordered_test_data): Likewise.
	(nextafter_test_data): Likewise.
	(nexttoward_test_data): Likewise.
	(remainder_test_data): Likewise.
	(remquo_test_data): Likewise.
	(significand_test_data): Likewise.
	* math/gen-libm-test.pl (%beautify): Add snan_value_ld.
2016-06-23 21:59:34 +00:00
Rajalakshmi Srinivasaraghavan
41a359e22f Add nextup and nextdown math functions
TS 18661 adds nextup and nextdown functions alongside nextafter to provide
support for float128 equivalent to it.  This patch adds nextupl, nextup,
nextupf, nextdownl, nextdown and nextdownf to libm before float128 support.

The nextup functions return the next representable value in the direction of
positive infinity and the nextdown functions return the next representable
value in the direction of negative infinity.  These are currently enabled
as GNU extensions.
2016-06-16 21:37:45 +05:30
Joseph Myers
228a78c21b Fix i386 fdim double rounding (bug 20255).
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.
2016-06-14 16:41:50 +00:00
Joseph Myers
f4015c8a86 Use generic fdim on more architectures (bug 6796, bug 20255, bug 20256).
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.
2016-06-14 16:04:19 +00:00
Joseph Myers
4fea2cda61 Simplify generic fdim implementations.
The generic fdim implementations have unnecessarily complicated code,
using fpclassify to determine whether the arguments are NaNs,
subtracting NaNs if so and otherwise subtracting the non-NaN arguments
if not (x <= y), then using fpclassify on the result to see if it is
infinite.

This patch simplifies the code.  Instead of handling NaNs separately,
it suffices to use an unordered comparison with islessequal (x, y) to
determine whether to return zero, and otherwise NaNs can go through
the same subtraction as non-NaN arguments; no explicit tests for NaN
are needed at all.  Then, isinf instead of fpclassify can be used to
determine whether to set errno (in the normal non-overflow case, only
one classification will need to occur, unlike the three in the
previous code, of which two occurred even if returning zero, because
the result will not be infinite in the normal case).

The resulting logic is essentially the same as that in the powerpc
version, except that the powerpc version is missing errno setting and
uses <= not islessequal, so relying on
<https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58684>, the GCC bug that
unordered comparison instructions are wrongly used on powerpc for
ordered comparisons.

The compiled code for fdim and fdimf on x86_64 is less than half the
size of the previous code.

Tested for x86_64.

	* math/s_fdim.c (__fdim): Use islessequal and isinf instead of
	fpclassify.
	* math/s_fdimf.c (__fdimf): Likewise.
	* math/s_fdiml.c (__fdiml): Likewise.
2016-06-14 14:56:42 +00:00
Joseph Myers
a2ae1696f7 Fix dbl-64 atan2 (sNaN, qNaN) (bug 20252).
The dbl-64 implementation of atan2, passed arguments (sNaN, qNaN),
fails to raise the "invalid" exception.  This patch fixes it to add
both arguments, rather than just adding the second argument to itself,
in the case where the second argument is a NaN (which is checked for
before checking for the first argument being a NaN).  sNaN tests for
atan2 are added, along with some qNaN tests I noticed were missing but
should have been there by analogy with other tests present.

Tested for x86_64 and x86.

	[BZ #20252]
	* sysdeps/ieee754/dbl-64/e_atan2.c (__ieee754_atan2): Add both
	arguments when second argument is a NaN.
	* math/libm-test.inc (atan2_test_data): Add sNaN tests and more
	qNaN tests.
2016-06-13 21:43:22 +00:00
Joseph Myers
5e19c4347f Add more sNaN tests (cimag, conj, copysign, creal, fma, fmod).
This patch adds tests of sNaN inputs to further libm functions.

Tested for x86_64 and x86.

	* math/libm-test.inc (cimag_test_data): Add sNaN tests.
	(conj_test_data): Likewise.
	(copysign_test_data): Likewise.
	(creal_test_data): Likewise.
	(fma_test_data): Likewise.
	(fmod_test_data): Likewise.
2016-06-13 21:26:28 +00:00
Joseph Myers
88283451b2 Fix frexp (NaN) (bug 20250).
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.
2016-06-13 17:27:19 +00:00
Joseph Myers
a6a4395d20 Fix modf (sNaN) (bug 20240).
Various modf implementations return sNaN (both outputs) for sNaN
input.  In fact they contain code to convert sNaN to qNaN for both
outputs, but the way this is done is multiplying by 1.0 (for a wider
range of inputs that includes NaNs as well as numbers with exponent
large enough to ensure that they are integers), and that
multiplication by 1.0 is optimized away by GCC in the absence of
-fsignaling-nans, unlike other operations on NaNs used for this
purpose that are not no-ops for non-sNaN input.  This patch arranges
for those files to be built with -fsignaling-nans so that this
existing code is effective as intended.

Tested for x86_64 and x86.

	[BZ #20240]
	* math/Makefile (CFLAGS-s_modf.c): New variable.
	(CFLAGS-s_modff.c): Likewise.
	(CFLAGS-s_modfl.c): Likewise.
	* math/libm-test.inc (modf_test_data): Add sNaN tests.
2016-06-10 23:16:27 +00:00
Joseph Myers
f00faa4a43 Fix i386/x86_64 log2l (sNaN) (bug 20235).
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.
2016-06-09 18:04:30 +00:00
Joseph Myers
8c010e2f71 Fix i386/x86_64 log1pl (sNaN) (bug 20229).
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.
2016-06-08 23:11:42 +00:00
Joseph Myers
09096b3615 Fix i386/x86_64 log10l (sNaN) (bug 20228).
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.
2016-06-08 22:59:18 +00:00
Joseph Myers
df179d8808 Fix i386/x86_64 logl (sNaN) (bug 20227).
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.
2016-06-08 22:24:06 +00:00
Joseph Myers
9bd3ef8e19 Fix i386/x86_64 expl, exp10l, expm1l for sNaN input (bug 20226).
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.
2016-06-08 21:55:06 +00:00
Joseph Myers
9946e7a949 Fix ldexp, scalbn, scalbln for sNaN input (bug 20225).
The wrapper implementations of ldexp / scalbn / scalbln
(architecture-independent), and their float / long double variants,
return sNaN for sNaN input.  This patch fixes them to add relevant
arguments to themselves so that qNaN is returned in this case.

Tested for x86_64 and x86.

	[BZ #20225]
	* math/s_ldexp.c (__ldexp): Add non-finite or zero argument to
	itself.
	* math/s_ldexpf.c (__ldexpf): Likewise.
	* math/s_ldexpl.c (__ldexpl): Likewise.
	* math/w_scalbln.c (__w_scalbln): Likewise.
	* math/w_scalblnf.c (__w_scalblnf): Likewise.
	* math/w_scalblnl.c (__w_scalblnl): Likewise.
	* math/libm-test.inc (scalbn_test_data): Add sNaN tests.
	(scalbln_test_data): Likewise.
2016-06-08 21:32:57 +00:00
Joseph Myers
40720ec9f9 Fix i386 cbrtl (sNaN) (bug 20224).
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.
2016-06-08 21:02:40 +00:00
Paul E. Murphy
5188b97325 Generate new format names in auto-libm-test-out
This converts the inclusion macro for each test to use
the format specific macro. In addition, the format
specifier is removed as it is applied via the LIT() macro
which is itself applied when converting the auto inputs and
libm-test.inc into libm-test.c.
2016-06-08 14:56:04 -05:00
Paul E. Murphy
760723ec6e Remove type specific information from auto-libm-test-in
Apply the following sed regexes to auto-libm-test-in in order:

s/flt-32/binary32/
s/dbl-64/binary64/
s/ldbl-96-intel/intel96/
s/ldbl-96-m68k/m68k96/
s/ldbl-128ibm/ibm128/
s/ldbl-128/binary128/

and fixup ldbl-96 comment manually.
2016-06-08 14:41:05 -05:00
Paul E. Murphy
9c665e085f Remove CHOOSE() macro from libm-tests.inc
Use gen-libm-test.pl to generate a list of macros
mapping to libm-test-ulps.h as this simplifies adding new
types without having to modify a growing number of
static headers each time a type is added.

This also removes the final usage of the TEST_(DOUBLE|FLOAT|LDOUBLE)
macros.  Thus, they too are removed.
2016-06-08 14:37:15 -05:00
Paul E. Murphy
8938513484 Apply LIT(x) to floating point literals in libm-test.c
With the exception of the second argument of nexttoward,
any suffixes should be stripped from the test input, and
the macro LIT(x) should be applied to use the correct
suffix for the type being tested.

This adds a new argument type "j" to gen-test-libm.pl
to signify an argument to a test input which does not
require fixup.  The test cases of nexttoward have
been updated to use this new feature.

This applies post-processing to all of the test inputs
through gen-libm-test.pl to strip literal suffixes and
apply the LIT(x) macro, with one exception stated above.
This seems a bit cleaner than tossing the macro onto
everything, albeit slightly more obfuscated.
2016-06-08 14:28:25 -05:00
Joseph Myers
8fa8a330f9 Fix i386 atanhl (sNaN) (bug 20219).
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.
2016-06-07 23:08:32 +00:00
Joseph Myers
c23805a95d Fix i386 asinhl (sNaN) (bug 20218).
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.
2016-06-07 22:54:58 +00:00
Joseph Myers
3d8b06bc61 Fix dbl-64 asin (sNaN) (bug 20213).
The dbl-64 version of asin returns sNaN for sNaN arguments.  This
patch fixes it to add NaN arguments to themselves so that qNaN is
returned in this case.

Tested for x86_64 and x86.

	[BZ #20213]
	* sysdeps/ieee754/dbl-64/e_asin.c (__ieee754_asin): Add NaN
	argument to itself.
	* math/libm-test.inc (asin_test_data): Add sNaN tests.
2016-06-06 22:21:11 +00:00
Joseph Myers
af0cfbaf1d Fix dbl-64 acos (sNaN) (bug 20212).
The dbl-64 version of acos returns sNaN for sNaN arguments.  This
patch fixes it to add NaN arguments to themselves so that qNaN is
returned in this case.

Tested for x86_64 and x86.

	[BZ #20212]
	* sysdeps/ieee754/dbl-64/e_asin.c (__ieee754_acos): Add NaN
	argument to itself.
	* math/libm-test.inc (acos_test_data): Add sNaN tests.
2016-06-06 22:10:11 +00:00
Joseph Myers
8cbd1453ec Fix x86/x86_64 nextafterl incrementing negative subnormals (bug 20205).
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.
2016-06-03 21:30:12 +00:00