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author | Joseph Myers <joseph@codesourcery.com> | 2016-09-23 21:54:21 +0000 |
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committer | Joseph Myers <joseph@codesourcery.com> | 2016-09-23 21:54:21 +0000 |
commit | bb8081f57f23a3e1b28b1b7104f24d17da9a3d82 (patch) | |
tree | 0987589e19a174ecc1550dfc366813e6102973ef /manual | |
parent | 4775578486c8ee2aa09b402eb272eb932e7e0691 (diff) | |
download | glibc-bb8081f57f23a3e1b28b1b7104f24d17da9a3d82.tar.gz glibc-bb8081f57f23a3e1b28b1b7104f24d17da9a3d82.tar.xz glibc-bb8081f57f23a3e1b28b1b7104f24d17da9a3d82.zip |
Add iszero.
TS 18661-1 adds an iszero classification macro to <math.h>. This patch implements it for glibc. There are no new underlying functions in libm because the implementation uses fpclassify when sNaN support is required and a direct comparison otherwise; any optimizations for this macro should be done through adding __builtin_iszero 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. Tested for x86_64 and x86. * math/math.h [__GLIBC_USE (IEC_60559_BFP_EXT)] (iszero): New macro. * math/libm-test.inc (iszero_test_data): New array. (iszero_test): New function. (main): Call iszero_test. * manual/arith.texi (Floating Point Classes): Document iszero. * manual/libm-err-tab.pl: Update comment on interfaces without ulps tabulated.
Diffstat (limited to 'manual')
-rw-r--r-- | manual/arith.texi | 8 | ||||
-rwxr-xr-x | manual/libm-err-tab.pl | 2 |
2 files changed, 9 insertions, 1 deletions
diff --git a/manual/arith.texi b/manual/arith.texi index bfa236a50e..58f35781bb 100644 --- a/manual/arith.texi +++ b/manual/arith.texi @@ -414,6 +414,14 @@ This macro returns a nonzero value if @var{x} is subnormal. It is from TS 18661-1:2014. @end deftypefn +@comment math.h +@comment ISO +@deftypefn {Macro} int iszero (@emph{float-type} @var{x}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +This macro returns a nonzero value if @var{x} is zero. 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 diff --git a/manual/libm-err-tab.pl b/manual/libm-err-tab.pl index adeadb8f55..2386772b85 100755 --- a/manual/libm-err-tab.pl +++ b/manual/libm-err-tab.pl @@ -78,7 +78,7 @@ use vars qw (%results @all_floats %suffices @all_functions); "scalbn", "sin", "sincos", "sinh", "sqrt", "tan", "tanh", "tgamma", "trunc", "y0", "y1", "yn" ); # fpclassify, isnormal, isfinite, isinf, isnan, issignaling, -# issubnormal, signbit, isgreater, isgreaterequal, isless, +# issubnormal, iszero, signbit, isgreater, isgreaterequal, isless, # islessequal, islessgreater, isunordered are not tabulated. if ($#ARGV == 0) { |