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authorJoseph Myers <joseph@codesourcery.com>2016-09-21 20:52:02 +0000
committerJoseph Myers <joseph@codesourcery.com>2016-09-21 20:52:02 +0000
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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.
Diffstat (limited to 'manual/arith.texi')
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diff --git a/manual/arith.texi b/manual/arith.texi
index dc3c367..bfa236a 100644
--- a/manual/arith.texi
+++ b/manual/arith.texi
@@ -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