| //===-- Memcpy implementation -----------------------------------*- C++ -*-===// |
| // |
| // 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 LLVM_LIBC_SRC_STRING_MEMORY_UTILS_MEMCPY_IMPLEMENTATIONS_H |
| #define LLVM_LIBC_SRC_STRING_MEMORY_UTILS_MEMCPY_IMPLEMENTATIONS_H |
| |
| #include "src/__support/macros/config.h" // LIBC_INLINE |
| #include "src/__support/macros/optimization.h" // LIBC_LOOP_NOUNROLL |
| #include "src/__support/macros/properties/architectures.h" |
| #include "src/string/memory_utils/op_builtin.h" |
| #include "src/string/memory_utils/utils.h" |
| |
| #include <stddef.h> // size_t |
| |
| #if defined(LIBC_TARGET_ARCH_IS_X86) |
| #include "src/string/memory_utils/x86_64/memcpy_implementations.h" |
| #elif defined(LIBC_TARGET_ARCH_IS_AARCH64) |
| #include "src/string/memory_utils/aarch64/memcpy_implementations.h" |
| #endif |
| |
| namespace __llvm_libc { |
| |
| [[maybe_unused]] LIBC_INLINE void |
| inline_memcpy_byte_per_byte(Ptr dst, CPtr src, size_t offset, size_t count) { |
| LIBC_LOOP_NOUNROLL |
| for (; offset < count; ++offset) |
| dst[offset] = src[offset]; |
| } |
| |
| [[maybe_unused]] LIBC_INLINE void |
| inline_memcpy_aligned_access_32bit(Ptr __restrict dst, CPtr __restrict src, |
| size_t count) { |
| constexpr size_t kAlign = sizeof(uint32_t); |
| if (count <= 2 * kAlign) |
| return inline_memcpy_byte_per_byte(dst, src, 0, count); |
| size_t bytes_to_dst_align = distance_to_align_up<kAlign>(dst); |
| inline_memcpy_byte_per_byte(dst, src, 0, bytes_to_dst_align); |
| size_t offset = bytes_to_dst_align; |
| size_t src_alignment = distance_to_align_down<kAlign>(src + offset); |
| for (; offset < count - kAlign; offset += kAlign) { |
| uint32_t value; |
| if (src_alignment == 0) |
| value = load32_aligned<uint32_t>(src, offset); |
| else if (src_alignment == 2) |
| value = load32_aligned<uint16_t, uint16_t>(src, offset); |
| else |
| value = load32_aligned<uint8_t, uint16_t, uint8_t>(src, offset); |
| store32_aligned<uint32_t>(value, dst, offset); |
| } |
| // remainder |
| inline_memcpy_byte_per_byte(dst, src, offset, count); |
| } |
| |
| [[maybe_unused]] LIBC_INLINE void |
| inline_memcpy_aligned_access_64bit(Ptr __restrict dst, CPtr __restrict src, |
| size_t count) { |
| constexpr size_t kAlign = sizeof(uint64_t); |
| if (count <= 2 * kAlign) |
| return inline_memcpy_byte_per_byte(dst, src, 0, count); |
| size_t bytes_to_dst_align = distance_to_align_up<kAlign>(dst); |
| inline_memcpy_byte_per_byte(dst, src, 0, bytes_to_dst_align); |
| size_t offset = bytes_to_dst_align; |
| size_t src_alignment = distance_to_align_down<kAlign>(src + offset); |
| for (; offset < count - kAlign; offset += kAlign) { |
| uint64_t value; |
| if (src_alignment == 0) |
| value = load64_aligned<uint64_t>(src, offset); |
| else if (src_alignment == 4) |
| value = load64_aligned<uint32_t, uint32_t>(src, offset); |
| else if (src_alignment == 2) |
| value = |
| load64_aligned<uint16_t, uint16_t, uint16_t, uint16_t>(src, offset); |
| else |
| value = load64_aligned<uint8_t, uint16_t, uint16_t, uint16_t, uint8_t>( |
| src, offset); |
| store64_aligned<uint64_t>(value, dst, offset); |
| } |
| // remainder |
| inline_memcpy_byte_per_byte(dst, src, offset, count); |
| } |
| |
| LIBC_INLINE void inline_memcpy(Ptr __restrict dst, CPtr __restrict src, |
| size_t count) { |
| using namespace __llvm_libc::builtin; |
| #if defined(LIBC_COPT_MEMCPY_USE_EMBEDDED_TINY) |
| return inline_memcpy_byte_per_byte(dst, src, 0, count); |
| #elif defined(LIBC_TARGET_ARCH_IS_X86) |
| return inline_memcpy_x86_maybe_interpose_repmovsb(dst, src, count); |
| #elif defined(LIBC_TARGET_ARCH_IS_AARCH64) |
| return inline_memcpy_aarch64(dst, src, count); |
| #elif defined(LIBC_TARGET_ARCH_IS_RISCV64) |
| return inline_memcpy_aligned_access_64bit(dst, src, count); |
| #elif defined(LIBC_TARGET_ARCH_IS_RISCV32) |
| return inline_memcpy_aligned_access_32bit(dst, src, count); |
| #else |
| return inline_memcpy_byte_per_byte(dst, src, 0, count); |
| #endif |
| } |
| |
| LIBC_INLINE void inline_memcpy(void *__restrict dst, const void *__restrict src, |
| size_t count) { |
| inline_memcpy(reinterpret_cast<Ptr>(dst), reinterpret_cast<CPtr>(src), count); |
| } |
| |
| } // namespace __llvm_libc |
| |
| #endif // LLVM_LIBC_SRC_STRING_MEMORY_UTILS_MEMCPY_IMPLEMENTATIONS_H |