1 //===-- Memset implementation for aarch64 -----------------------*- C++ -*-===// 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-exception 6 // 7 //===----------------------------------------------------------------------===// 8 #ifndef LIBC_SRC_STRING_MEMORY_UTILS_AARCH64_INLINE_MEMSET_H 9 #define LIBC_SRC_STRING_MEMORY_UTILS_AARCH64_INLINE_MEMSET_H 10 11 #include "src/__support/macros/attributes.h" // LIBC_INLINE 12 #include "src/__support/macros/config.h" 13 #include "src/string/memory_utils/op_aarch64.h" 14 #include "src/string/memory_utils/op_generic.h" 15 #include "src/string/memory_utils/utils.h" // Ptr, CPtr 16 17 #include <stddef.h> // size_t 18 19 namespace LIBC_NAMESPACE_DECL { 20 21 [[maybe_unused]] LIBC_INLINE static void 22 inline_memset_aarch64(Ptr dst, uint8_t value, size_t count) { 23 static_assert(aarch64::kNeon, "aarch64 supports vector types"); 24 using uint128_t = generic_v128; 25 using uint256_t = generic_v256; 26 using uint512_t = generic_v512; 27 if (count == 0) 28 return; 29 if (count <= 3) { 30 generic::Memset<uint8_t>::block(dst, value); 31 if (count > 1) 32 generic::Memset<uint16_t>::tail(dst, value, count); 33 return; 34 } 35 if (count <= 8) 36 return generic::Memset<uint32_t>::head_tail(dst, value, count); 37 if (count <= 16) 38 return generic::Memset<uint64_t>::head_tail(dst, value, count); 39 if (count <= 32) 40 return generic::Memset<uint128_t>::head_tail(dst, value, count); 41 if (count <= (32 + 64)) { 42 generic::Memset<uint256_t>::block(dst, value); 43 if (count <= 64) 44 return generic::Memset<uint256_t>::tail(dst, value, count); 45 generic::Memset<uint256_t>::block(dst + 32, value); 46 generic::Memset<uint256_t>::tail(dst, value, count); 47 return; 48 } 49 if (count >= 448 && value == 0 && aarch64::neon::hasZva()) { 50 generic::Memset<uint512_t>::block(dst, 0); 51 align_to_next_boundary<64>(dst, count); 52 return aarch64::neon::BzeroCacheLine::loop_and_tail(dst, 0, count); 53 } else { 54 generic::Memset<uint128_t>::block(dst, value); 55 align_to_next_boundary<16>(dst, count); 56 return generic::Memset<uint512_t>::loop_and_tail(dst, value, count); 57 } 58 } 59 60 } // namespace LIBC_NAMESPACE_DECL 61 62 #endif // LIBC_SRC_STRING_MEMORY_UTILS_AARCH64_INLINE_MEMSET_H 63