| //===-- Implementation of memmove -----------------------------------------===// |
| // |
| // 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 |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "src/string/memmove.h" |
| |
| #include "src/__support/common.h" |
| #include "src/__support/integer_operations.h" |
| #include "src/string/memory_utils/elements.h" |
| #include <stddef.h> // size_t, ptrdiff_t |
| |
| namespace __llvm_libc { |
| |
| static inline void inline_memmove(char *dst, const char *src, size_t count) { |
| using namespace __llvm_libc::scalar; |
| if (count == 0) |
| return; |
| if (count == 1) |
| return move<_1>(dst, src); |
| if (count <= 4) |
| return move<HeadTail<_2>>(dst, src, count); |
| if (count <= 8) |
| return move<HeadTail<_4>>(dst, src, count); |
| if (count <= 16) |
| return move<HeadTail<_8>>(dst, src, count); |
| if (count <= 32) |
| return move<HeadTail<_16>>(dst, src, count); |
| if (count <= 64) |
| return move<HeadTail<_32>>(dst, src, count); |
| if (count <= 128) |
| return move<HeadTail<_64>>(dst, src, count); |
| |
| using AlignedMoveLoop = Align<_16, Arg::Src>::Then<Loop<_64>>; |
| if (dst < src) |
| return move<AlignedMoveLoop>(dst, src, count); |
| else if (dst > src) |
| return move_backward<AlignedMoveLoop>(dst, src, count); |
| } |
| |
| LLVM_LIBC_FUNCTION(void *, memmove, |
| (void *dst, const void *src, size_t count)) { |
| inline_memmove(reinterpret_cast<char *>(dst), |
| reinterpret_cast<const char *>(src), count); |
| return dst; |
| } |
| |
| } // namespace __llvm_libc |