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