/* SPDX-License-Identifier: GPL-2.0 */ /* * NH - ε-almost-universal hash function, x86_64 AVX2 accelerated * * Copyright 2018 Google LLC * * Author: Eric Biggers <[email protected]> */ #include <linux/linkage.h> #include <linux/cfi_types.h> #define PASS0_SUMS %ymm0 #define PASS1_SUMS %ymm1 #define PASS2_SUMS %ymm2 #define PASS3_SUMS %ymm3 #define K0 %ymm4 #define K0_XMM %xmm4 #define K1 %ymm5 #define K1_XMM %xmm5 #define K2 %ymm6 #define K2_XMM %xmm6 #define K3 %ymm7 #define K3_XMM %xmm7 #define T0 %ymm8 #define T1 %ymm9 #define T2 %ymm10 #define T2_XMM %xmm10 #define T3 %ymm11 #define T3_XMM %xmm11 #define T4 %ymm12 #define T5 %ymm13 #define T6 %ymm14 #define T7 %ymm15 #define KEY %rdi #define MESSAGE %rsi #define MESSAGE_LEN %rdx #define HASH %rcx .macro _nh_2xstride k0, k1, k2, k3 // Add message words to key words vpaddd \k0, T3, T0 vpaddd \k1, T3, T1 vpaddd \k2, T3, T2 vpaddd \k3, T3, T3 // Multiply 32x32 => 64 and accumulate vpshufd $0x10, T0, T4 vpshufd $0x32, T0, T0 vpshufd $0x10, T1, T5 vpshufd $0x32, T1, T1 vpshufd $0x10, T2, T6 vpshufd $0x32, T2, T2 vpshufd $0x10, T3, T7 vpshufd $0x32, T3, T3 vpmuludq T4, T0, T0 vpmuludq T5, T1, T1 vpmuludq T6, T2, T2 vpmuludq T7, T3, T3 vpaddq T0, PASS0_SUMS, PASS0_SUMS vpaddq T1, PASS1_SUMS, PASS1_SUMS vpaddq T2, PASS2_SUMS, PASS2_SUMS vpaddq T3, PASS3_SUMS, PASS3_SUMS .endm /* * void nh_avx2(const u32 *key, const u8 *message, size_t message_len, * __le64 hash[NH_NUM_PASSES]) * * It's guaranteed that message_len % 16 == 0. */ SYM_TYPED_FUNC_START(nh_avx2) vmovdqu 0x00(KEY), K0 vmovdqu 0x10(KEY), K1 add $0x20, KEY vpxor PASS0_SUMS, PASS0_SUMS, PASS0_SUMS vpxor PASS1_SUMS, PASS1_SUMS, PASS1_SUMS vpxor PASS2_SUMS, PASS2_SUMS, PASS2_SUMS vpxor PASS3_SUMS, PASS3_SUMS, PASS3_SUMS sub $0x40, MESSAGE_LEN jl .Lloop4_done .Lloop4: vmovdqu (MESSAGE), T3 vmovdqu 0x00(KEY), K2 vmovdqu 0x10(KEY), K3 _nh_2xstride K0, K1, K2, K3 vmovdqu 0x20(MESSAGE), T3 vmovdqu 0x20(KEY), K0 vmovdqu 0x30(KEY), K1 _nh_2xstride K2, K3, K0, K1 add $0x40, MESSAGE add $0x40, KEY sub $0x40, MESSAGE_LEN jge .Lloop4 .Lloop4_done: and $0x3f, MESSAGE_LEN jz .Ldone cmp $0x20, MESSAGE_LEN jl .Llast // 2 or 3 strides remain; do 2 more. vmovdqu (MESSAGE), T3 vmovdqu 0x00(KEY), K2 vmovdqu 0x10(KEY), K3 _nh_2xstride K0, K1, K2, K3 add $0x20, MESSAGE add $0x20, KEY sub $0x20, MESSAGE_LEN jz .Ldone vmovdqa K2, K0 vmovdqa K3, K1 .Llast: // Last stride. Zero the high 128 bits of the message and keys so they // don't affect the result when processing them like 2 strides. vmovdqu (MESSAGE), T3_XMM vmovdqa K0_XMM, K0_XMM vmovdqa K1_XMM, K1_XMM vmovdqu 0x00(KEY), K2_XMM vmovdqu 0x10(KEY), K3_XMM _nh_2xstride K0, K1, K2, K3 .Ldone: // Sum the accumulators for each pass, then store the sums to 'hash' // PASS0_SUMS is (0A 0B 0C 0D) // PASS1_SUMS is (1A 1B 1C 1D) // PASS2_SUMS is (2A 2B 2C 2D) // PASS3_SUMS is (3A 3B 3C 3D) // We need the horizontal sums: // (0A + 0B + 0C + 0D, // 1A + 1B + 1C + 1D, // 2A + 2B + 2C + 2D, // 3A + 3B + 3C + 3D) // vpunpcklqdq PASS1_SUMS, PASS0_SUMS, T0 // T0 = (0A 1A 0C 1C) vpunpckhqdq PASS1_SUMS, PASS0_SUMS, T1 // T1 = (0B 1B 0D 1D) vpunpcklqdq PASS3_SUMS, PASS2_SUMS, T2 // T2 = (2A 3A 2C 3C) vpunpckhqdq PASS3_SUMS, PASS2_SUMS, T3 // T3 = (2B 3B 2D 3D) vinserti128 $0x1, T2_XMM, T0, T4 // T4 = (0A 1A 2A 3A) vinserti128 $0x1, T3_XMM, T1, T5 // T5 = (0B 1B 2B 3B) vperm2i128 $0x31, T2, T0, T0 // T0 = (0C 1C 2C 3C) vperm2i128 $0x31, T3, T1, T1 // T1 = (0D 1D 2D 3D) vpaddq T5, T4, T4 vpaddq T1, T0, T0 vpaddq T4, T0, T0 vmovdqu T0, (HASH) vzeroupper RET SYM_FUNC_END(nh_avx2)
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