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/*
* Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/Types.h>
#if defined(KERNEL)
# include <Kernel/StdLib.h>
#else
# include <stdlib.h>
# include <string.h>
#endif
ALWAYS_INLINE void fast_u32_copy(u32* dest, const u32* src, size_t count)
{
#if ARCH(I386)
asm volatile(
"rep movsl\n"
: "+S"(src), "+D"(dest), "+c"(count)::"memory");
#else
__builtin_memcpy(dest, src, count * 4);
#endif
}
ALWAYS_INLINE void fast_u32_fill(u32* dest, u32 value, size_t count)
{
#if ARCH(I386)
asm volatile(
"rep stosl\n"
: "=D"(dest), "=c"(count)
: "D"(dest), "c"(count), "a"(value)
: "memory");
#else
for (auto* p = dest; p < (dest + count); ++p) {
*p = value;
}
#endif
}
namespace AK {
inline void secure_zero(void* ptr, size_t size)
{
__builtin_memset(ptr, 0, size);
// The memory barrier is here to avoid the compiler optimizing
// away the memset when we rely on it for wiping secrets.
asm volatile("" ::
: "memory");
}
}
using AK::secure_zero;
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