libstdc++-v3/ChangeLog:
* include/bits/simd_reductions.h: New file.
Signed-off-by: Matthias Kretz <[email protected]>
---
libstdc++-v3/include/bits/simd_reductions.h | 112 ++++++++++++++++++++
1 file changed, 112 insertions(+)
create mode 100644 libstdc++-v3/include/bits/simd_reductions.h
--
──────────────────────────────────────────────────────────────────────────
Dr. Matthias Kretz https://mattkretz.github.io
GSI Helmholtz Center for Heavy Ion Research https://gsi.de
std::simd
──────────────────────────────────────────────────────────────────────────diff --git a/libstdc++-v3/include/bits/simd_reductions.h b/libstdc++-v3/include/bits/simd_reductions.h
new file mode 100644
index 00000000000..127cde01dee
--- /dev/null
+++ b/libstdc++-v3/include/bits/simd_reductions.h
@@ -0,0 +1,112 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later WITH GCC-exception-3.1 */
+/* Copyright © 2025 GSI Helmholtzzentrum fuer Schwerionenforschung GmbH
+ * Matthias Kretz <[email protected]>
+ */
+
+#ifndef _GLIBCXX_SIMD_REDUCTIONS_H
+#define _GLIBCXX_SIMD_REDUCTIONS_H 1
+
+#ifdef _GLIBCXX_SYSHDR
+#pragma GCC system_header
+#endif
+
+#if __cplusplus >= 202400L
+
+#include "simd_vec.h"
+
+// psabi warnings are bogus because the ABI of the internal types never leaks into user code
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wpsabi"
+
+// [simd.reductions] ----------------------------------------------------------
+namespace std::simd
+{
+ template <typename _Tp, typename _BinaryOperation>
+ inline constexpr _Tp __identity_element_for = nullptr;
+
+ template <typename _Tp>
+ inline constexpr _Tp __identity_element_for<_Tp, plus<>> = _Tp(0);
+
+ template <typename _Tp>
+ inline constexpr _Tp __identity_element_for<_Tp, multiplies<>> = _Tp(1);
+
+ template <typename _Tp>
+ inline constexpr _Tp __identity_element_for<_Tp, bit_and<>> = _Tp(~_Tp());
+
+ template <typename _Tp>
+ inline constexpr _Tp __identity_element_for<_Tp, bit_or<>> = _Tp(0);
+
+ template <typename _Tp>
+ inline constexpr _Tp __identity_element_for<_Tp, bit_xor<>> = _Tp(0);
+
+ template <typename _Tp, typename _BinaryOperation>
+ requires same_as<_BinaryOperation, plus<>>
+ or same_as<_BinaryOperation, multiplies<>>
+ or same_as<_BinaryOperation, bit_and<>>
+ or same_as<_BinaryOperation, bit_or<>>
+ or same_as<_BinaryOperation, bit_xor<>>
+ consteval _Tp __default_identity_element()
+ { return __identity_element_for<_Tp, _BinaryOperation>; }
+
+ template <typename _Tp, typename _Ap, __reduction_binary_operation<_Tp> _BinaryOperation = plus<>>
+ [[__gnu__::__always_inline__]]
+ constexpr _Tp
+ reduce(const basic_vec<_Tp, _Ap>& __x, _BinaryOperation __binary_op = {})
+ { return __x._M_reduce(__binary_op); }
+
+ template <typename _Tp, typename _Ap, __reduction_binary_operation<_Tp> _BinaryOperation = plus<>>
+ [[__gnu__::__always_inline__]]
+ constexpr _Tp
+ reduce(const basic_vec<_Tp, _Ap>& __x, const typename basic_vec<_Tp, _Ap>::mask_type& __mask,
+ _BinaryOperation __binary_op = {}, type_identity_t<_Tp> __identity_element
+ = __default_identity_element<_Tp, _BinaryOperation>())
+ { return reduce(select(__mask, __x, __identity_element), __binary_op); }
+
+ template <totally_ordered _Tp, typename _Ap>
+ [[__gnu__::__always_inline__]]
+ constexpr _Tp
+ reduce_min(const basic_vec<_Tp, _Ap>& __x) noexcept
+ {
+ return reduce(__x, []<typename _UV>(const _UV& __a, const _UV& __b) {
+ return select(__a < __b, __a, __b);
+ });
+ }
+
+ template <totally_ordered _Tp, typename _Ap>
+ [[__gnu__::__always_inline__]]
+ constexpr _Tp
+ reduce_min(const basic_vec<_Tp, _Ap>& __x,
+ const typename basic_vec<_Tp, _Ap>::mask_type& __mask) noexcept
+ {
+ return reduce(select(__mask, __x, numeric_limits<_Tp>::max()),
+ []<typename _UV>(const _UV& __a, const _UV& __b) {
+ return select(__a < __b, __a, __b);
+ });
+ }
+
+ template <totally_ordered _Tp, typename _Ap>
+ [[__gnu__::__always_inline__]]
+ constexpr _Tp
+ reduce_max(const basic_vec<_Tp, _Ap>& __x) noexcept
+ {
+ return reduce(__x, []<typename _UV>(const _UV& __a, const _UV& __b) {
+ return select(__a < __b, __b, __a);
+ });
+ }
+
+ template <totally_ordered _Tp, typename _Ap>
+ [[__gnu__::__always_inline__]]
+ constexpr _Tp
+ reduce_max(const basic_vec<_Tp, _Ap>& __x,
+ const typename basic_vec<_Tp, _Ap>::mask_type& __mask) noexcept
+ {
+ return reduce(select(__mask, __x, numeric_limits<_Tp>::lowest()),
+ []<typename _UV>(const _UV& __a, const _UV& __b) {
+ return select(__a < __b, __b, __a);
+ });
+ }
+}
+
+#pragma GCC diagnostic pop
+#endif // C++26
+#endif // _GLIBCXX_SIMD_REDUCTIONS_H
