From d942e95cd7e493efbbff58b78e63013c79e634cd Mon Sep 17 00:00:00 2001 From: Joseph Myers Date: Wed, 21 Sep 2016 20:52:02 +0000 Subject: Add issubnormal. TS 18661-1 adds an issubnormal classification macro to . 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 features from TS 18661-1 is like: * New 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. --- math/math.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'math/math.h') diff --git a/math/math.h b/math/math.h index 2f77dee..064cc56 100644 --- a/math/math.h +++ b/math/math.h @@ -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 -- cgit v1.1