From f82a4bdb73328bc53bdcc344622acbd96522a83c Mon Sep 17 00:00:00 2001 From: Joseph Myers Date: Fri, 28 Oct 2016 21:15:26 +0000 Subject: [PATCH] Add SNAN, SNANF, SNANL macros. TS 18661-1 defines SNAN macros for signaling NaN values, suitable for use in static initializers. This patch adds them to glibc's (provided you are building with GCC 3.3 or later; no attempt is made to provide any kind of nonconforming fallback for older compilers without the __builtin_nans functions). Tested for x86_64 and x86. * math/math.h [__GLIBC_USE (IEC_60559_BFP_EXT) && __GNUC_PREREQ (3, 3)] (SNANF): New macro. [__GLIBC_USE (IEC_60559_BFP_EXT) && __GNUC_PREREQ (3, 3)] (SNAN): Likewise. [__GLIBC_USE (IEC_60559_BFP_EXT) && __GNUC_PREREQ (3, 3)] (SNANL): Likewise. * manual/arith.texi (Infinity and NaN): Document SNANF, SNAN and SNANL. * math/test-double.h (snan_value_MACRO): New macro. * math/test-float.h (snan_value_MACRO): Likewise. * math/test-ldouble.h (snan_value_MACRO): Likewise. * math/libm-test.inc (issignaling_test_data): Add tests of snan_value_MACRO. --- ChangeLog | 17 +++++++++++++++++ NEWS | 2 ++ manual/arith.texi | 9 +++++++++ math/libm-test.inc | 2 ++ math/math.h | 9 +++++++++ math/test-double.h | 1 + math/test-float.h | 1 + math/test-ldouble.h | 1 + 8 files changed, 42 insertions(+) diff --git a/ChangeLog b/ChangeLog index d5b3f7bb7e..eed5cc5f37 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,20 @@ +2016-10-28 Joseph Myers + + * math/math.h + [__GLIBC_USE (IEC_60559_BFP_EXT) && __GNUC_PREREQ (3, 3)] (SNANF): + New macro. + [__GLIBC_USE (IEC_60559_BFP_EXT) && __GNUC_PREREQ (3, 3)] (SNAN): + Likewise. + [__GLIBC_USE (IEC_60559_BFP_EXT) && __GNUC_PREREQ (3, 3)] (SNANL): + Likewise. + * manual/arith.texi (Infinity and NaN): Document SNANF, SNAN and + SNANL. + * math/test-double.h (snan_value_MACRO): New macro. + * math/test-float.h (snan_value_MACRO): Likewise. + * math/test-ldouble.h (snan_value_MACRO): Likewise. + * math/libm-test.inc (issignaling_test_data): Add tests of + snan_value_MACRO. + 2016-10-28 Tulio Magno Quites Machado Filho * nptl/pthread_rwlock_unlock.c: Add a comment explaining its diff --git a/NEWS b/NEWS index 2da72cdf7a..65184b11da 100644 --- a/NEWS +++ b/NEWS @@ -51,6 +51,8 @@ Version 2.25 * New features are added from TS 18661-1:2014: + - Signaling NaN macros: SNANF, SNAN, SNANL. + - Comparison macros: iseqsig. - Classification macros: iscanonical, issubnormal, iszero. diff --git a/manual/arith.texi b/manual/arith.texi index a5c04e475f..f0f3bb4031 100644 --- a/manual/arith.texi +++ b/manual/arith.texi @@ -711,6 +711,15 @@ such as by defining @code{_GNU_SOURCE}, and then you must include @file{math.h}.) @end deftypevr +@comment math.h +@comment ISO +@deftypevr Macro float SNANF +@deftypevrx Macro double SNAN +@deftypevrx Macro {long double} SNANL +These macros, defined by TS 18661-1:2014, are constant expressions for +signaling NaNs. +@end deftypevr + @w{IEEE 754} also allows for another unusual value: negative zero. This value is produced when you divide a positive number by negative infinity, or when a negative result is smaller than the limits of diff --git a/math/libm-test.inc b/math/libm-test.inc index 710633842c..88420ee613 100644 --- a/math/libm-test.inc +++ b/math/libm-test.inc @@ -8901,6 +8901,8 @@ static const struct test_f_i_data issignaling_test_data[] = TEST_f_b (issignaling, -qnan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), TEST_f_b (issignaling, snan_value, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), TEST_f_b (issignaling, -snan_value, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), + TEST_f_b (issignaling, snan_value_MACRO, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), + TEST_f_b (issignaling, -snan_value_MACRO, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED), }; static void diff --git a/math/math.h b/math/math.h index 7c0c709523..70d9b864e8 100644 --- a/math/math.h +++ b/math/math.h @@ -45,6 +45,15 @@ __BEGIN_DECLS # include #endif /* __USE_ISOC99 */ +#if __GLIBC_USE (IEC_60559_BFP_EXT) +/* Signaling NaN macros, if supported. */ +# if __GNUC_PREREQ (3, 3) +# define SNANF (__builtin_nansf ("")) +# define SNAN (__builtin_nans ("")) +# define SNANL (__builtin_nansl ("")) +# endif +#endif + /* Get the architecture specific values describing the floating-point evaluation. The following symbols will get defined: diff --git a/math/test-double.h b/math/test-double.h index b9e8cd840c..e172b8fb4d 100644 --- a/math/test-double.h +++ b/math/test-double.h @@ -27,3 +27,4 @@ #define TYPE_STR "double" #define LITM(x) x #define FTOSTR snprintf +#define snan_value_MACRO SNAN diff --git a/math/test-float.h b/math/test-float.h index e783c094c9..ea096c8aaa 100644 --- a/math/test-float.h +++ b/math/test-float.h @@ -28,3 +28,4 @@ /* Use the double variants of macro constants. */ #define LITM(x) x #define FTOSTR snprintf +#define snan_value_MACRO SNANF diff --git a/math/test-ldouble.h b/math/test-ldouble.h index b877711758..62c9eb8859 100644 --- a/math/test-ldouble.h +++ b/math/test-ldouble.h @@ -27,3 +27,4 @@ #define LIT(x) (x ## L) #define LITM(x) x ## l #define FTOSTR snprintf +#define snan_value_MACRO SNANL