Skip to content

Enable __builtin_bit_cast for CUDA #3066

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
Stephan T. Lavavej (StephanTLavavej) merged 1 commit into from
Sep 1, 2022
Merged

Enable __builtin_bit_cast for CUDA #3066

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
4 changes: 2 additions & 2 deletions stl/inc/complex
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -133,7 +133,7 @@ namespace _Float_multi_prec {
// multiplication

// round to 26 significant bits, ties toward zero
_NODISCARD _CONSTEXPR_BIT_CAST double _High_half(const double _Val) noexcept {
_NODISCARD constexpr double _High_half(const double _Val) noexcept {
const auto _Bits = _Bit_cast<unsigned long long>(_Val);
const auto _High_half_bits = (_Bits + 0x3ff'ffffULL) & 0xffff'ffff'f800'0000ULL;
return _Bit_cast<double>(_High_half_bits);
Expand All @@ -144,7 +144,7 @@ namespace _Float_multi_prec {
// 1) _Prod0 is _Xval^2 faithfully rounded
// 2) no internal overflow or underflow occurs
// violation of condition 1 could lead to relative error on the order of epsilon
_NODISCARD _CONSTEXPR_BIT_CAST double _Sqr_error_fallback(const double _Xval, const double _Prod0) noexcept {
_NODISCARD constexpr double _Sqr_error_fallback(const double _Xval, const double _Prod0) noexcept {
const double _Xhigh = _High_half(_Xval);
const double _Xlow = _Xval - _Xhigh;
return ((_Xhigh * _Xhigh - _Prod0) + 2.0 * _Xhigh * _Xlow) + _Xlow * _Xlow;
Expand Down
30 changes: 9 additions & 21 deletions stl/inc/xutility
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -43,12 +43,6 @@ _STL_DISABLE_CLANG_WARNINGS
#endif // _USE_STD_VECTOR_ALGORITHMS
#endif // ^^^ no support for vector algorithms ^^^

#ifdef __CUDACC__
#define _CONSTEXPR_BIT_CAST inline
#else // ^^^ workaround ^^^ / vvv no workaround vvv
#define _CONSTEXPR_BIT_CAST constexpr
#endif // ^^^ no workaround ^^^

#if _USE_STD_VECTOR_ALGORITHMS
_EXTERN_C
// The "noalias" attribute tells the compiler optimizer that pointers going into these hand-vectorized algorithms
Expand Down Expand Up @@ -152,14 +146,8 @@ template <class _To, class _From,
enable_if_t<conjunction_v<bool_constant<sizeof(_To) == sizeof(_From)>, is_trivially_copyable<_To>,
is_trivially_copyable<_From>>,
int> = 0>
_NODISCARD _CONSTEXPR_BIT_CAST _To _Bit_cast(const _From& _Val) noexcept {
#ifdef __CUDACC__
_To _To_obj; // assumes default-init
_CSTD memcpy(_STD addressof(_To_obj), _STD addressof(_Val), sizeof(_To));
return _To_obj;
#else // ^^^ workaround ^^^ / vvv no workaround vvv
_NODISCARD constexpr _To _Bit_cast(const _From& _Val) noexcept {
return __builtin_bit_cast(_To, _Val);
#endif // ^^^ no workaround ^^^
}

template <class _Ty>
Expand Down Expand Up @@ -5053,7 +5041,7 @@ _NODISCARD _CONSTEXPR20 _InIt _Find_unchecked(_InIt _First, const _InIt _Last, c
#else // ^^^ _USE_STD_VECTOR_ALGORITHMS ^^^ / vvv not _USE_STD_VECTOR_ALGORITHMS vvv
if constexpr (sizeof(_Iter_value_t<_InIt>) == 1) {
const auto _First_ptr = _To_address(_First);
const auto _Result = static_cast<remove_reference_t<_Iter_ref_t<_InIt>>*>(
const auto _Result = static_cast<remove_reference_t<_Iter_ref_t<_InIt>>*>(
_CSTD memchr(_First_ptr, static_cast<unsigned char>(_Val), static_cast<size_t>(_Last - _First)));
if constexpr (is_pointer_v<_InIt>) {
return _Result ? _Result : _Last;
Expand Down Expand Up @@ -6037,28 +6025,28 @@ struct _CXX17_DEPRECATE_ITERATOR_BASE_CLASS iterator { // base type for iterator
};

template <class _Ty, enable_if_t<is_floating_point_v<_Ty>, int> = 0>
_NODISCARD _CONSTEXPR_BIT_CAST auto _Float_abs_bits(const _Ty& _Xx) {
_NODISCARD constexpr auto _Float_abs_bits(const _Ty& _Xx) {
using _Traits = _Floating_type_traits<_Ty>;
using _Uint_type = typename _Traits::_Uint_type;
const auto _Bits = _Bit_cast<_Uint_type>(_Xx);
return _Bits & ~_Traits::_Shifted_sign_mask;
}

template <class _Ty, enable_if_t<is_floating_point_v<_Ty>, int> = 0>
_NODISCARD _CONSTEXPR_BIT_CAST _Ty _Float_abs(const _Ty _Xx) { // constexpr floating-point abs()
_NODISCARD constexpr _Ty _Float_abs(const _Ty _Xx) { // constexpr floating-point abs()
return _Bit_cast<_Ty>(_Float_abs_bits(_Xx));
}

template <class _Ty, enable_if_t<is_floating_point_v<_Ty>, int> = 0>
_NODISCARD _CONSTEXPR_BIT_CAST _Ty _Float_copysign(const _Ty _Magnitude, const _Ty _Sign) { // constexpr copysign()
_NODISCARD constexpr _Ty _Float_copysign(const _Ty _Magnitude, const _Ty _Sign) { // constexpr copysign()
using _Traits = _Floating_type_traits<_Ty>;
using _Uint_type = typename _Traits::_Uint_type;
const auto _Signbit = _Bit_cast<_Uint_type>(_Sign) & _Traits::_Shifted_sign_mask;
return _Bit_cast<_Ty>(_Float_abs_bits(_Magnitude) | _Signbit);
}

template <class _Ty, enable_if_t<is_floating_point_v<_Ty>, int> = 0>
_NODISCARD _CONSTEXPR_BIT_CAST bool _Is_nan(const _Ty _Xx) { // constexpr isnan()
_NODISCARD constexpr bool _Is_nan(const _Ty _Xx) { // constexpr isnan()
using _Traits = _Floating_type_traits<_Ty>;
return _Float_abs_bits(_Xx) > _Traits::_Shifted_exponent_mask;
}
Expand All @@ -6068,20 +6056,20 @@ _NODISCARD _CONSTEXPR_BIT_CAST bool _Is_nan(const _Ty _Xx) { // constexpr isnan(
// When the value is a 32-bit or 64-bit signaling NaN, the conversion to/from 80-bit raises FE_INVALID
// and turns it into a quiet NaN. This behavior is undesirable if we want to test for signaling NaNs.
template <class _Ty, enable_if_t<is_floating_point_v<_Ty>, int> = 0>
_NODISCARD _CONSTEXPR_BIT_CAST bool _Is_signaling_nan(const _Ty& _Xx) { // returns true if input is a signaling NaN
_NODISCARD constexpr bool _Is_signaling_nan(const _Ty& _Xx) { // returns true if input is a signaling NaN
using _Traits = _Floating_type_traits<_Ty>;
const auto _Abs_bits = _Float_abs_bits(_Xx);
return _Abs_bits > _Traits::_Shifted_exponent_mask && ((_Abs_bits & _Traits::_Special_nan_mantissa_mask) == 0);
}

template <class _Ty, enable_if_t<is_floating_point_v<_Ty>, int> = 0>
_NODISCARD _CONSTEXPR_BIT_CAST bool _Is_inf(const _Ty _Xx) { // constexpr isinf()
_NODISCARD constexpr bool _Is_inf(const _Ty _Xx) { // constexpr isinf()
using _Traits = _Floating_type_traits<_Ty>;
return _Float_abs_bits(_Xx) == _Traits::_Shifted_exponent_mask;
}

template <class _Ty, enable_if_t<is_floating_point_v<_Ty>, int> = 0>
_NODISCARD _CONSTEXPR_BIT_CAST bool _Is_finite(const _Ty _Xx) { // constexpr isfinite()
_NODISCARD constexpr bool _Is_finite(const _Ty _Xx) { // constexpr isfinite()
using _Traits = _Floating_type_traits<_Ty>;
return _Float_abs_bits(_Xx) < _Traits::_Shifted_exponent_mask;
}
Expand Down