38 lines · cpp
1//===-- Implementation of memmove -----------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#include "src/string/memmove.h"10#include "src/__support/macros/config.h"11#include "src/__support/macros/null_check.h"12#include "src/string/memory_utils/inline_memcpy.h"13#include "src/string/memory_utils/inline_memmove.h"14#include <stddef.h> // size_t15 16namespace LIBC_NAMESPACE_DECL {17 18LLVM_LIBC_FUNCTION(void *, memmove,19 (void *dst, const void *src, size_t count)) {20 if (count) {21 LIBC_CRASH_ON_NULLPTR(dst);22 LIBC_CRASH_ON_NULLPTR(src);23 }24 // Memmove may handle some small sizes as efficiently as inline_memcpy.25 // For these sizes we may not do is_disjoint check.26 // This both avoids additional code for the most frequent smaller sizes27 // and removes code bloat (we don't need the memcpy logic for small sizes).28 if (inline_memmove_small_size(dst, src, count))29 return dst;30 if (is_disjoint(dst, src, count))31 inline_memcpy(dst, src, count);32 else33 inline_memmove_follow_up(dst, src, count);34 return dst;35}36 37} // namespace LIBC_NAMESPACE_DECL38