ladybird/AK/BitCast.h

/*
 * Copyright (c) 2021, the SerenityOS developers.
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#pragma once

#include <AK/Platform.h>

namespace AK {

template<typename T, typename U>
[[nodiscard]] constexpr ALWAYS_INLINE T bit_cast(U const& a)
{
#if (__has_builtin(__builtin_bit_cast))
    return __builtin_bit_cast(T, a);
#else
    static_assert(sizeof(T) == sizeof(U));

    T result;
    __builtin_memcpy(&result, &a, sizeof(T));
    return result;
#endif
}

}

#if USING_AK_GLOBALLY
using AK::bit_cast;
#endif
AK: Implement bit_cast 2021-03-22 18:25:06 +00:00			`/*`
			`* Copyright (c) 2021, the SerenityOS developers.`
			`*`
Everything: Move to SPDX license identifiers in all files. SPDX License Identifiers are a more compact / standardized way of representing file license information. See: https://spdx.dev/resources/use/#identifiers This was done with the `ambr` search and replace tool. ambr --no-parent-ignore --key-from-file --rep-from-file key.txt rep.txt * 2021-04-22 08:24:48 +00:00			`* SPDX-License-Identifier: BSD-2-Clause`
AK: Implement bit_cast 2021-03-22 18:25:06 +00:00			`*/`

			`#pragma once`

AK: Make it possible to not `using` AK classes into the global namespace This patch adds the `USING_AK_GLOBALLY` macro which is enabled by default, but can be overridden by build flags. This is a step towards integrating Jakt and AK types. 2022-11-26 11:18:30 +00:00			`#include <AK/Platform.h>`

AK: Implement bit_cast 2021-03-22 18:25:06 +00:00			`namespace AK {`

			`template<typename T, typename U>`
AK: Use bit_cast in SIMDExtras.h/AK::Detail::byte_reverse_impl This necessitates marking bit_cast as ALWAYS_INLINE since emitting it as a function call there will create an unnecessary potential SSE registers -> plain registers/memory round-trip. 2024-07-05 16:46:18 +00:00			`[[nodiscard]] constexpr ALWAYS_INLINE T bit_cast(U const& a)`
AK: Implement bit_cast 2021-03-22 18:25:06 +00:00			`{`
AK: Use `__builtin_bit_cast` if available We now use the compiler's buitin version of bitcast if it's available instead of just resorting to using the builtin `memcpy`. 2021-08-21 05:08:06 +00:00			`#if (__has_builtin(__builtin_bit_cast))`
			`return __builtin_bit_cast(T, a);`
			`#else`
AK: Implement bit_cast 2021-03-22 18:25:06 +00:00			`static_assert(sizeof(T) == sizeof(U));`

			`T result;`
			`__builtin_memcpy(&result, &a, sizeof(T));`
			`return result;`
AK: Use `__builtin_bit_cast` if available We now use the compiler's buitin version of bitcast if it's available instead of just resorting to using the builtin `memcpy`. 2021-08-21 05:08:06 +00:00			`#endif`
AK: Implement bit_cast 2021-03-22 18:25:06 +00:00			`}`

			`}`

AK: Make it possible to not `using` AK classes into the global namespace This patch adds the `USING_AK_GLOBALLY` macro which is enabled by default, but can be overridden by build flags. This is a step towards integrating Jakt and AK types. 2022-11-26 11:18:30 +00:00			`#if USING_AK_GLOBALLY`
AK: Implement bit_cast 2021-03-22 18:25:06 +00:00			`using AK::bit_cast;`
AK: Make it possible to not `using` AK classes into the global namespace This patch adds the `USING_AK_GLOBALLY` macro which is enabled by default, but can be overridden by build flags. This is a step towards integrating Jakt and AK types. 2022-11-26 11:18:30 +00:00			`#endif`