1/* SPDX-License-Identifier: GPL-2.0 */ 2/* 3 * NH - ε-almost-universal hash function, x86_64 AVX2 accelerated 4 * 5 * Copyright 2018 Google LLC 6 * 7 * Author: Eric Biggers <ebiggers@google.com> 8 */ 9 10#include <linux/linkage.h> 11#include <linux/cfi_types.h> 12 13#define PASS0_SUMS %ymm0 14#define PASS1_SUMS %ymm1 15#define PASS2_SUMS %ymm2 16#define PASS3_SUMS %ymm3 17#define K0 %ymm4 18#define K0_XMM %xmm4 19#define K1 %ymm5 20#define K1_XMM %xmm5 21#define K2 %ymm6 22#define K2_XMM %xmm6 23#define K3 %ymm7 24#define K3_XMM %xmm7 25#define T0 %ymm8 26#define T1 %ymm9 27#define T2 %ymm10 28#define T2_XMM %xmm10 29#define T3 %ymm11 30#define T3_XMM %xmm11 31#define T4 %ymm12 32#define T5 %ymm13 33#define T6 %ymm14 34#define T7 %ymm15 35#define KEY %rdi 36#define MESSAGE %rsi 37#define MESSAGE_LEN %rdx 38#define HASH %rcx 39 40.macro _nh_2xstride k0, k1, k2, k3 41 42 // Add message words to key words 43 vpaddd \k0, T3, T0 44 vpaddd \k1, T3, T1 45 vpaddd \k2, T3, T2 46 vpaddd \k3, T3, T3 47 48 // Multiply 32x32 => 64 and accumulate 49 vpshufd $0x10, T0, T4 50 vpshufd $0x32, T0, T0 51 vpshufd $0x10, T1, T5 52 vpshufd $0x32, T1, T1 53 vpshufd $0x10, T2, T6 54 vpshufd $0x32, T2, T2 55 vpshufd $0x10, T3, T7 56 vpshufd $0x32, T3, T3 57 vpmuludq T4, T0, T0 58 vpmuludq T5, T1, T1 59 vpmuludq T6, T2, T2 60 vpmuludq T7, T3, T3 61 vpaddq T0, PASS0_SUMS, PASS0_SUMS 62 vpaddq T1, PASS1_SUMS, PASS1_SUMS 63 vpaddq T2, PASS2_SUMS, PASS2_SUMS 64 vpaddq T3, PASS3_SUMS, PASS3_SUMS 65.endm 66 67/* 68 * void nh_avx2(const u32 *key, const u8 *message, size_t message_len, 69 * __le64 hash[NH_NUM_PASSES]) 70 * 71 * It's guaranteed that message_len % 16 == 0. 72 */ 73SYM_TYPED_FUNC_START(nh_avx2) 74 75 vmovdqu 0x00(KEY), K0 76 vmovdqu 0x10(KEY), K1 77 add $0x20, KEY 78 vpxor PASS0_SUMS, PASS0_SUMS, PASS0_SUMS 79 vpxor PASS1_SUMS, PASS1_SUMS, PASS1_SUMS 80 vpxor PASS2_SUMS, PASS2_SUMS, PASS2_SUMS 81 vpxor PASS3_SUMS, PASS3_SUMS, PASS3_SUMS 82 83 sub $0x40, MESSAGE_LEN 84 jl .Lloop4_done 85.Lloop4: 86 vmovdqu (MESSAGE), T3 87 vmovdqu 0x00(KEY), K2 88 vmovdqu 0x10(KEY), K3 89 _nh_2xstride K0, K1, K2, K3 90 91 vmovdqu 0x20(MESSAGE), T3 92 vmovdqu 0x20(KEY), K0 93 vmovdqu 0x30(KEY), K1 94 _nh_2xstride K2, K3, K0, K1 95 96 add $0x40, MESSAGE 97 add $0x40, KEY 98 sub $0x40, MESSAGE_LEN 99 jge .Lloop4 100 101.Lloop4_done: 102 and $0x3f, MESSAGE_LEN 103 jz .Ldone 104 105 cmp $0x20, MESSAGE_LEN 106 jl .Llast 107 108 // 2 or 3 strides remain; do 2 more. 109 vmovdqu (MESSAGE), T3 110 vmovdqu 0x00(KEY), K2 111 vmovdqu 0x10(KEY), K3 112 _nh_2xstride K0, K1, K2, K3 113 add $0x20, MESSAGE 114 add $0x20, KEY 115 sub $0x20, MESSAGE_LEN 116 jz .Ldone 117 vmovdqa K2, K0 118 vmovdqa K3, K1 119.Llast: 120 // Last stride. Zero the high 128 bits of the message and keys so they 121 // don't affect the result when processing them like 2 strides. 122 vmovdqu (MESSAGE), T3_XMM 123 vmovdqa K0_XMM, K0_XMM 124 vmovdqa K1_XMM, K1_XMM 125 vmovdqu 0x00(KEY), K2_XMM 126 vmovdqu 0x10(KEY), K3_XMM 127 _nh_2xstride K0, K1, K2, K3 128 129.Ldone: 130 // Sum the accumulators for each pass, then store the sums to 'hash' 131 132 // PASS0_SUMS is (0A 0B 0C 0D) 133 // PASS1_SUMS is (1A 1B 1C 1D) 134 // PASS2_SUMS is (2A 2B 2C 2D) 135 // PASS3_SUMS is (3A 3B 3C 3D) 136 // We need the horizontal sums: 137 // (0A + 0B + 0C + 0D, 138 // 1A + 1B + 1C + 1D, 139 // 2A + 2B + 2C + 2D, 140 // 3A + 3B + 3C + 3D) 141 // 142 143 vpunpcklqdq PASS1_SUMS, PASS0_SUMS, T0 // T0 = (0A 1A 0C 1C) 144 vpunpckhqdq PASS1_SUMS, PASS0_SUMS, T1 // T1 = (0B 1B 0D 1D) 145 vpunpcklqdq PASS3_SUMS, PASS2_SUMS, T2 // T2 = (2A 3A 2C 3C) 146 vpunpckhqdq PASS3_SUMS, PASS2_SUMS, T3 // T3 = (2B 3B 2D 3D) 147 148 vinserti128 $0x1, T2_XMM, T0, T4 // T4 = (0A 1A 2A 3A) 149 vinserti128 $0x1, T3_XMM, T1, T5 // T5 = (0B 1B 2B 3B) 150 vperm2i128 $0x31, T2, T0, T0 // T0 = (0C 1C 2C 3C) 151 vperm2i128 $0x31, T3, T1, T1 // T1 = (0D 1D 2D 3D) 152 153 vpaddq T5, T4, T4 154 vpaddq T1, T0, T0 155 vpaddq T4, T0, T0 156 vmovdqu T0, (HASH) 157 RET 158SYM_FUNC_END(nh_avx2) 159