| /* SPDX-License-Identifier: GPL-2.0 */ |
| /* |
| * NH - ε-almost-universal hash function, x86_64 SSE2 accelerated |
| * |
| * Copyright 2018 Google LLC |
| * |
| * Author: Eric Biggers <ebiggers@google.com> |
| */ |
| |
| #include <linux/linkage.h> |
| |
| #define PASS0_SUMS %xmm0 |
| #define PASS1_SUMS %xmm1 |
| #define PASS2_SUMS %xmm2 |
| #define PASS3_SUMS %xmm3 |
| #define K0 %xmm4 |
| #define K1 %xmm5 |
| #define K2 %xmm6 |
| #define K3 %xmm7 |
| #define T0 %xmm8 |
| #define T1 %xmm9 |
| #define T2 %xmm10 |
| #define T3 %xmm11 |
| #define T4 %xmm12 |
| #define T5 %xmm13 |
| #define T6 %xmm14 |
| #define T7 %xmm15 |
| #define KEY %rdi |
| #define MESSAGE %rsi |
| #define MESSAGE_LEN %rdx |
| #define HASH %rcx |
| |
| .macro _nh_stride k0, k1, k2, k3, offset |
| |
| // Load next message stride |
| movdqu \offset(MESSAGE), T1 |
| |
| // Load next key stride |
| movdqu \offset(KEY), \k3 |
| |
| // Add message words to key words |
| movdqa T1, T2 |
| movdqa T1, T3 |
| paddd T1, \k0 // reuse k0 to avoid a move |
| paddd \k1, T1 |
| paddd \k2, T2 |
| paddd \k3, T3 |
| |
| // Multiply 32x32 => 64 and accumulate |
| pshufd $0x10, \k0, T4 |
| pshufd $0x32, \k0, \k0 |
| pshufd $0x10, T1, T5 |
| pshufd $0x32, T1, T1 |
| pshufd $0x10, T2, T6 |
| pshufd $0x32, T2, T2 |
| pshufd $0x10, T3, T7 |
| pshufd $0x32, T3, T3 |
| pmuludq T4, \k0 |
| pmuludq T5, T1 |
| pmuludq T6, T2 |
| pmuludq T7, T3 |
| paddq \k0, PASS0_SUMS |
| paddq T1, PASS1_SUMS |
| paddq T2, PASS2_SUMS |
| paddq T3, PASS3_SUMS |
| .endm |
| |
| /* |
| * void nh_sse2(const u32 *key, const u8 *message, size_t message_len, |
| * u8 hash[NH_HASH_BYTES]) |
| * |
| * It's guaranteed that message_len % 16 == 0. |
| */ |
| ENTRY(nh_sse2) |
| |
| movdqu 0x00(KEY), K0 |
| movdqu 0x10(KEY), K1 |
| movdqu 0x20(KEY), K2 |
| add $0x30, KEY |
| pxor PASS0_SUMS, PASS0_SUMS |
| pxor PASS1_SUMS, PASS1_SUMS |
| pxor PASS2_SUMS, PASS2_SUMS |
| pxor PASS3_SUMS, PASS3_SUMS |
| |
| sub $0x40, MESSAGE_LEN |
| jl .Lloop4_done |
| .Lloop4: |
| _nh_stride K0, K1, K2, K3, 0x00 |
| _nh_stride K1, K2, K3, K0, 0x10 |
| _nh_stride K2, K3, K0, K1, 0x20 |
| _nh_stride K3, K0, K1, K2, 0x30 |
| add $0x40, KEY |
| add $0x40, MESSAGE |
| sub $0x40, MESSAGE_LEN |
| jge .Lloop4 |
| |
| .Lloop4_done: |
| and $0x3f, MESSAGE_LEN |
| jz .Ldone |
| _nh_stride K0, K1, K2, K3, 0x00 |
| |
| sub $0x10, MESSAGE_LEN |
| jz .Ldone |
| _nh_stride K1, K2, K3, K0, 0x10 |
| |
| sub $0x10, MESSAGE_LEN |
| jz .Ldone |
| _nh_stride K2, K3, K0, K1, 0x20 |
| |
| .Ldone: |
| // Sum the accumulators for each pass, then store the sums to 'hash' |
| movdqa PASS0_SUMS, T0 |
| movdqa PASS2_SUMS, T1 |
| punpcklqdq PASS1_SUMS, T0 // => (PASS0_SUM_A PASS1_SUM_A) |
| punpcklqdq PASS3_SUMS, T1 // => (PASS2_SUM_A PASS3_SUM_A) |
| punpckhqdq PASS1_SUMS, PASS0_SUMS // => (PASS0_SUM_B PASS1_SUM_B) |
| punpckhqdq PASS3_SUMS, PASS2_SUMS // => (PASS2_SUM_B PASS3_SUM_B) |
| paddq PASS0_SUMS, T0 |
| paddq PASS2_SUMS, T1 |
| movdqu T0, 0x00(HASH) |
| movdqu T1, 0x10(HASH) |
| ret |
| ENDPROC(nh_sse2) |
