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1//===-- Memcmp implementation for x86_64 ------------------------*- 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-exception6//7//===----------------------------------------------------------------------===//8 9#ifndef LLVM_LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMCMP_H10#define LLVM_LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMCMP_H11 12#include "src/__support/macros/attributes.h" // LIBC_INLINE13#include "src/__support/macros/optimization.h" // LIBC_UNLIKELY14#include "src/string/memory_utils/op_generic.h"15#include "src/string/memory_utils/op_x86.h"16#include "src/string/memory_utils/utils.h" // MemcmpReturnType17 18namespace LIBC_NAMESPACE_DECL {19 20[[maybe_unused]] LIBC_INLINE MemcmpReturnType21inline_memcmp_generic_gt16(CPtr p1, CPtr p2, size_t count) {22 return generic::Memcmp<uint64_t>::loop_and_tail_align_above(384, p1, p2,23 count);24}25 26#if defined(__SSE4_1__)27[[maybe_unused]] LIBC_INLINE MemcmpReturnType28inline_memcmp_x86_sse41_gt16(CPtr p1, CPtr p2, size_t count) {29 return generic::Memcmp<__m128i>::loop_and_tail_align_above(384, p1, p2,30 count);31}32#endif // __SSE4_1__33 34#if defined(__AVX2__)35[[maybe_unused]] LIBC_INLINE MemcmpReturnType36inline_memcmp_x86_avx2_gt16(CPtr p1, CPtr p2, size_t count) {37 if (count <= 32)38 return generic::Memcmp<__m128i>::head_tail(p1, p2, count);39 if (count <= 64)40 return generic::Memcmp<__m256i>::head_tail(p1, p2, count);41 return generic::Memcmp<__m256i>::loop_and_tail_align_above(384, p1, p2,42 count);43}44#endif // __AVX2__45 46#if defined(__AVX512BW__)47[[maybe_unused]] LIBC_INLINE MemcmpReturnType48inline_memcmp_x86_avx512bw_gt16(CPtr p1, CPtr p2, size_t count) {49 if (count <= 32)50 return generic::Memcmp<__m128i>::head_tail(p1, p2, count);51 if (count <= 64)52 return generic::Memcmp<__m256i>::head_tail(p1, p2, count);53 if (count <= 128)54 return generic::Memcmp<__m512i>::head_tail(p1, p2, count);55 return generic::Memcmp<__m512i>::loop_and_tail_align_above(384, p1, p2,56 count);57}58#endif // __AVX512BW__59 60LIBC_INLINE MemcmpReturnType inline_memcmp_x86(CPtr p1, CPtr p2, size_t count) {61 if (count == 0)62 return MemcmpReturnType::zero();63 if (count == 1)64 return generic::Memcmp<uint8_t>::block(p1, p2);65 if (count == 2)66 return generic::Memcmp<uint16_t>::block(p1, p2);67 if (count == 3)68 return generic::MemcmpSequence<uint16_t, uint8_t>::block(p1, p2);69 if (count == 4)70 return generic::Memcmp<uint32_t>::block(p1, p2);71 if (count == 5)72 return generic::MemcmpSequence<uint32_t, uint8_t>::block(p1, p2);73 if (count == 6)74 return generic::MemcmpSequence<uint32_t, uint16_t>::block(p1, p2);75 if (count == 7)76 return generic::Memcmp<uint32_t>::head_tail(p1, p2, 7);77 if (count == 8)78 return generic::Memcmp<uint64_t>::block(p1, p2);79 if (count <= 16)80 return generic::Memcmp<uint64_t>::head_tail(p1, p2, count);81#if defined(__AVX512BW__)82 return inline_memcmp_x86_avx512bw_gt16(p1, p2, count);83#elif defined(__AVX2__)84 return inline_memcmp_x86_avx2_gt16(p1, p2, count);85#elif defined(__SSE4_1__)86 return inline_memcmp_x86_sse41_gt16(p1, p2, count);87#else88 return inline_memcmp_generic_gt16(p1, p2, count);89#endif90}91 92} // namespace LIBC_NAMESPACE_DECL93 94#endif // LLVM_LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMCMP_H95