Add issubnormal.

TS 18661-1 adds an issubnormal classification macro to <math.h>.  This
patch implements it for glibc.  There are no new underlying functions
in libm because the implementation uses fpclassify; any optimizations
for this macro should be done through adding __builtin_subnormal in
GCC and using it in the header for suitable GCC versions, not through
adding other optimized inline or out-of-line versions to glibc.

The intended structure of the NEWS entry for <math.h> features from TS
18661-1 is like:

* New <math.h> features are added from TS 18661-1:2014:

  - Nearest integer functions: roundeven, roundevenf, roundevenl.

  - Comparison macros: iseqsig.

  - Classification macros: iscanonical, issubnormal, iszero.

(that is, following the grouping of interfaces in TS 18661-1:2014,
with any group where any interfaces are new in glibc 2.25 being listed
like that).

Tested for x86_64 and x86.

	* math/math.h [__GLIBC_USE (IEC_60559_BFP_EXT)] (issubnormal): New
	macro.
	* math/libm-test.inc (issubnormal_test_data): New array.
	(issubnormal_test): New function.
	* manual/arith.texi (Floating Point Classes): Document
	issubnormal.
	* manual/libm-err-tab.pl: Update comment on interfaces without
	ulps tabulated.
This commit is contained in:
Joseph Myers 2016-09-21 20:52:02 +00:00
parent 5b17fd0da6
commit d942e95cd7
6 changed files with 54 additions and 4 deletions

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@ -1,5 +1,14 @@
2016-09-21 Joseph Myers <joseph@codesourcery.com>
* math/math.h [__GLIBC_USE (IEC_60559_BFP_EXT)] (issubnormal): New
macro.
* math/libm-test.inc (issubnormal_test_data): New array.
(issubnormal_test): New function.
* manual/arith.texi (Floating Point Classes): Document
issubnormal.
* manual/libm-err-tab.pl: Update comment on interfaces without
ulps tabulated.
* sysdeps/generic/stdint.h: Define
__GLIBC_INTERNAL_STARTING_HEADER_IMPLEMENTATION and include
<bits/libc-header-start.h> instead of including <features.h>.

4
NEWS
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@ -49,6 +49,10 @@ Version 2.25
UINTMAX_WIDTH, PTRDIFF_WIDTH, SIG_ATOMIC_WIDTH, SIZE_WIDTH, WCHAR_WIDTH,
WINT_WIDTH.
* New <math.h> features are added from TS 18661-1:2014:
- Classification macros: issubnormal.
* The <sys/quota.h> header now includes the <linux/quota.h> header. Support
for the Linux quota interface which predates kernel version 2.4.22 has
been removed.

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@ -406,6 +406,14 @@ This macro returns a nonzero value if @var{x} is a signaling NaN
(sNaN). It is from TS 18661-1:2014.
@end deftypefn
@comment math.h
@comment ISO
@deftypefn {Macro} int issubnormal (@emph{float-type} @var{x})
@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
This macro returns a nonzero value if @var{x} is subnormal. It is
from TS 18661-1:2014.
@end deftypefn
Another set of floating-point classification functions was provided by
BSD. @Theglibc{} also supports these functions; however, we
recommend that you use the ISO C99 macros in new code. Those are standard

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@ -77,9 +77,9 @@ use vars qw (%results @all_floats %suffices @all_functions);
"nextup", "pow", "remainder", "remquo", "rint", "round", "scalb",
"scalbn", "sin", "sincos", "sinh", "sqrt", "tan", "tanh", "tgamma",
"trunc", "y0", "y1", "yn" );
# fpclassify, isnormal, isfinite, isinf, isnan, issignaling, signbit,
# isgreater, isgreaterequal, isless, islessequal, islessgreater, isunordered
# are not tabulated.
# fpclassify, isnormal, isfinite, isinf, isnan, issignaling,
# issubnormal, signbit, isgreater, isgreaterequal, isless,
# islessequal, islessgreater, isunordered are not tabulated.
if ($#ARGV == 0) {
$sources = $ARGV[0];

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@ -46,7 +46,7 @@
cbrt, ceil, copysign, cos, cosh, drem, erf, erfc, exp, exp10, exp2, expm1,
fabs, fdim, finite, floor, fma, fmax, fmin, fmod, fpclassify,
frexp, gamma, hypot,
ilogb, isfinite, isinf, isnan, isnormal, issignaling,
ilogb, isfinite, isinf, isnan, isnormal, issignaling, issubnormal,
isless, islessequal, isgreater, isgreaterequal, islessgreater, isunordered,
j0, j1, jn,
ldexp, lgamma, log, log10, log1p, log2, logb,
@ -8587,6 +8587,31 @@ issignaling_test (void)
ALL_RM_TEST (issignaling, 1, issignaling_test_data, RUN_TEST_LOOP_f_b_tg, END);
}
static const struct test_f_i_data issubnormal_test_data[] =
{
TEST_f_b (issubnormal, 0, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_b (issubnormal, minus_zero, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_b (issubnormal, 10, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_b (issubnormal, min_subnorm_value, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_b (issubnormal, -min_subnorm_value, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_b (issubnormal, min_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_b (issubnormal, -min_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_b (issubnormal, max_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_b (issubnormal, -max_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_b (issubnormal, plus_infty, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_b (issubnormal, minus_infty, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_b (issubnormal, qnan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_b (issubnormal, -qnan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_b (issubnormal, snan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
TEST_f_b (issubnormal, -snan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
};
static void
issubnormal_test (void)
{
ALL_RM_TEST (issubnormal, 1, issubnormal_test_data, RUN_TEST_LOOP_f_b_tg, END);
}
static const struct test_ff_i_data isunordered_test_data[] =
{
TEST_ff_i (isunordered, minus_zero, minus_zero, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
@ -12668,6 +12693,7 @@ main (int argc, char **argv)
isnan_test ();
isnormal_test ();
issignaling_test ();
issubnormal_test ();
signbit_test ();
/* Trigonometric functions: */

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@ -328,6 +328,9 @@ enum
: sizeof (x) == sizeof (double) \
? __issignaling (x) : __issignalingl (x))
# endif
/* Return nonzero value if X is subnormal. */
# define issubnormal(x) (fpclassify (x) == FP_SUBNORMAL)
#endif /* Use IEC_60559_BFP_EXT. */
#ifdef __USE_MISC