1 //===-- Elementary operations for aarch64 --------------------------------===// 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 9 #ifndef LLVM_LIBC_SRC_STRING_MEMORY_UTILS_ELEMENTS_AARCH64_H 10 #define LLVM_LIBC_SRC_STRING_MEMORY_UTILS_ELEMENTS_AARCH64_H 11 12 #include <src/string/memory_utils/elements.h> 13 #include <stddef.h> // size_t 14 #include <stdint.h> // uint8_t, uint16_t, uint32_t, uint64_t 15 16 #ifdef __ARM_NEON 17 #include <arm_neon.h> 18 #endif 19 20 namespace __llvm_libc { 21 namespace aarch64 { 22 23 using _1 = __llvm_libc::scalar::_1; 24 using _2 = __llvm_libc::scalar::_2; 25 using _3 = __llvm_libc::scalar::_3; 26 using _4 = __llvm_libc::scalar::_4; 27 using _8 = __llvm_libc::scalar::_8; 28 using _16 = __llvm_libc::scalar::_16; 29 30 #ifdef __ARM_NEON 31 struct N32 { 32 static constexpr size_t kSize = 32; EqualsN3233 static bool Equals(const char *lhs, const char *rhs) { 34 uint8x16_t l_0 = vld1q_u8((const uint8_t *)lhs); 35 uint8x16_t r_0 = vld1q_u8((const uint8_t *)rhs); 36 uint8x16_t l_1 = vld1q_u8((const uint8_t *)(lhs + 16)); 37 uint8x16_t r_1 = vld1q_u8((const uint8_t *)(rhs + 16)); 38 uint8x16_t temp = vpmaxq_u8(veorq_u8(l_0, r_0), veorq_u8(l_1, r_1)); 39 uint64_t res = 40 vgetq_lane_u64(vreinterpretq_u64_u8(vpmaxq_u8(temp, temp)), 0); 41 return res == 0; 42 } ThreeWayCompareN3243 static int ThreeWayCompare(const char *lhs, const char *rhs) { 44 uint8x16_t l_0 = vld1q_u8((const uint8_t *)lhs); 45 uint8x16_t r_0 = vld1q_u8((const uint8_t *)rhs); 46 uint8x16_t l_1 = vld1q_u8((const uint8_t *)(lhs + 16)); 47 uint8x16_t r_1 = vld1q_u8((const uint8_t *)(rhs + 16)); 48 uint8x16_t temp = vpmaxq_u8(veorq_u8(l_0, r_0), veorq_u8(l_1, r_1)); 49 uint64_t res = 50 vgetq_lane_u64(vreinterpretq_u64_u8(vpmaxq_u8(temp, temp)), 0); 51 if (res == 0) 52 return 0; 53 size_t index = (__builtin_ctzl(res) >> 3) << 2; 54 uint32_t l = *((const uint32_t *)(lhs + index)); 55 uint32_t r = *((const uint32_t *)(rhs + index)); 56 return __llvm_libc::scalar::_4::ScalarThreeWayCompare(l, r); 57 } 58 }; 59 60 using _32 = N32; 61 #else 62 using _32 = __llvm_libc::scalar::_32; 63 #endif // __ARM_NEON 64 65 } // namespace aarch64 66 } // namespace __llvm_libc 67 68 #endif // LLVM_LIBC_SRC_STRING_MEMORY_UTILS_ELEMENTS_AARCH64_H 69