[libcxx-commits] [libcxx] [libc++] Vectorize std::mismatch with trivially equality comparable types (PR #87716)

[Louis Dionne via libcxx-commits]

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@@ -0,0 +1,125 @@
+//===----------------------------------------------------------------------===//
+//
+// 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___ITERATOR_ALIASING_ITERATOR_H
+#define _LIBCPP___ITERATOR_ALIASING_ITERATOR_H
+
+#include <__config>
+#include <__iterator/iterator_traits.h>
+#include <__memory/pointer_traits.h>
+#include <__type_traits/is_trivial.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+// This iterator wrapper is used to type-pun an iterator to return a different type. This is done without UB by not
+// actually punning the type, but instread inspecting the object representation of the base type and copying that into
----------------
ldionne wrote:

```suggestion
// actually punning the type, but instead inspecting the object representation of the base type and copying that into
```

https://github.com/llvm/llvm-project/pull/87716