[libcxx-commits] [libcxx] [libc++] Vectorize mismatch (PR #73255)

[Louis Dionne via libcxx-commits]

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@@ -0,0 +1,121 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_SIMD_UTILS_H
+#define _LIBCPP___ALGORITHM_SIMD_UTILS_H
+
+#include <__bit/bit_cast.h>
+#include <__bit/countr.h>
+#include <__config>
+#include <__type_traits/is_arithmetic.h>
+#include <__type_traits/is_same.h>
+#include <__utility/integer_sequence.h>
+#include <cstddef>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 14 && __has_attribute(__ext_vector_type__) && __has_builtin(__builtin_reduce_and) &&            \
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ldionne wrote:

Would it make sense to conditionalize on `_LIBCPP_COMPILER_CLANG_BASED` instead? We are sometimes surprised to see that a branch isn't taken when we base it on "complicated" stuff like this, whereas we are guaranteed that it gets taken if we just conditionalize on the compiler version. We just have to check what version is sufficient.

https://github.com/llvm/llvm-project/pull/73255