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| author | Jakub Jelinek <jakub@redhat.com> | 2022-10-31 16:47:23 +0100 |
|---|---|---|
| committer | Jakub Jelinek <jakub@redhat.com> | 2022-10-31 16:49:04 +0100 |
| commit | cbf56503d5e2bbafb06a507cb37d30805a1013a0 (patch) | |
| tree | 3d61e1c42c25c298261165a927f04cf713fe3191 | |
| parent | 1b07d374765dd811cbb8b3e05764aef3b1754ff2 (diff) | |
| download | gcc-cbf56503d5e2bbafb06a507cb37d30805a1013a0.zip gcc-cbf56503d5e2bbafb06a507cb37d30805a1013a0.tar.gz gcc-cbf56503d5e2bbafb06a507cb37d30805a1013a0.tar.bz2 | |
libstdc++: Small extended float support tweaks
The following patch
1) enables the std::float128_t overloads for x86 with glibc 2.26+
2) makes std::nextafter(std::float16_t, std::float16_t) and
std::nextafter(std::bfloat16_t, std::bfloat16_t) constexpr
3) adds (small) testsuite coverage for that
2022-10-21 Jakub Jelinek <jakub@redhat.com>
* config/os/gnu-linux/os_defines.h (_GLIBCXX_HAVE_FLOAT128_MATH):
Uncomment.
* include/c_global/cmath (nextafter(_Float16, _Float16)): Make it constexpr.
If std::__is_constant_evaluated() call __builtin_nextafterf16.
(nextafter(__gnu_cxx::__bfloat16_t, __gnu_cxx::__bfloat16_t)): Similarly
but call __builtin_nextafterf16b.
* testsuite/26_numerics/headers/cmath/nextafter_c++23.cc (test): Add
static assertions to test constexpr nextafter.
| -rw-r--r-- | libstdc++-v3/config/os/gnu-linux/os_defines.h | 2 | ||||
| -rw-r--r-- | libstdc++-v3/include/c_global/cmath | 8 | ||||
| -rw-r--r-- | libstdc++-v3/testsuite/26_numerics/headers/cmath/nextafter_c++23.cc | 2 |
3 files changed, 9 insertions, 3 deletions
diff --git a/libstdc++-v3/config/os/gnu-linux/os_defines.h b/libstdc++-v3/config/os/gnu-linux/os_defines.h index e5b640a..044b4fc 100644 --- a/libstdc++-v3/config/os/gnu-linux/os_defines.h +++ b/libstdc++-v3/config/os/gnu-linux/os_defines.h @@ -57,7 +57,7 @@ || (defined(__powerpc__) && defined(_ARCH_PWR8) \ && defined(__LITTLE_ENDIAN__) && (_CALL_ELF == 2) \ && defined(__FLOAT128__))) -//# define _GLIBCXX_HAVE_FLOAT128_MATH 1 +# define _GLIBCXX_HAVE_FLOAT128_MATH 1 #endif #if __GLIBC_PREREQ(2, 27) diff --git a/libstdc++-v3/include/c_global/cmath b/libstdc++-v3/include/c_global/cmath index 555d644..e52055a 100644 --- a/libstdc++-v3/include/c_global/cmath +++ b/libstdc++-v3/include/c_global/cmath @@ -2755,9 +2755,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION nearbyint(_Float16 __x) { return _Float16(__builtin_nearbyintf(__x)); } - inline _Float16 + constexpr _Float16 nextafter(_Float16 __x, _Float16 __y) { + if (std::__is_constant_evaluated()) + return __builtin_nextafterf16(__x, __y); #ifdef __INT16_TYPE__ using __float16_int_type = __INT16_TYPE__; #else @@ -3471,9 +3473,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION nearbyint(__gnu_cxx::__bfloat16_t __x) { return __gnu_cxx::__bfloat16_t(__builtin_nearbyintf(__x)); } - inline __gnu_cxx::__bfloat16_t + constexpr __gnu_cxx::__bfloat16_t nextafter(__gnu_cxx::__bfloat16_t __x, __gnu_cxx::__bfloat16_t __y) { + if (std::__is_constant_evaluated()) + return __builtin_nextafterf16b(__x, __y); #ifdef __INT16_TYPE__ using __bfloat16_int_type = __INT16_TYPE__; #else diff --git a/libstdc++-v3/testsuite/26_numerics/headers/cmath/nextafter_c++23.cc b/libstdc++-v3/testsuite/26_numerics/headers/cmath/nextafter_c++23.cc index 45aa3b7..8d7daa9 100644 --- a/libstdc++-v3/testsuite/26_numerics/headers/cmath/nextafter_c++23.cc +++ b/libstdc++-v3/testsuite/26_numerics/headers/cmath/nextafter_c++23.cc @@ -100,6 +100,8 @@ test () VERIFY(std::fpclassify(t36) == FP_NAN); T t37 = std::nextafter(T(-0.0), T()); VERIFY(t37 == T() && !std::signbit(t37)); + static_assert(std::nextafter(T(1.0), T(2.0)) > T(1.0)); + static_assert(std::nextafter(std::nextafter(T(1.0), T(5.0)), T(0.0)) == T(1.0)); } int |