| /* slide_hash_neon.c -- Optimized hash table shifting for ARM with support for NEON instructions |
| * Copyright (C) 2017-2020 Mika T. Lindqvist |
| * |
| * Authors: |
| * Mika T. Lindqvist <postmaster@raasu.org> |
| * Jun He <jun.he@arm.com> |
| * |
| * For conditions of distribution and use, see copyright notice in zlib.h |
| */ |
| |
| #if defined(ARM_NEON_SLIDEHASH) |
| #include "neon_intrins.h" |
| #include "../../zbuild.h" |
| #include "../../deflate.h" |
| |
| /* SIMD version of hash_chain rebase */ |
| static inline void slide_hash_chain(Pos *table, uint32_t entries, uint16_t wsize) { |
| Z_REGISTER uint16x8_t v; |
| uint16x8x4_t p0, p1; |
| Z_REGISTER size_t n; |
| |
| size_t size = entries*sizeof(table[0]); |
| Assert((size % sizeof(uint16x8_t) * 8 == 0), "hash table size err"); |
| |
| Assert(sizeof(Pos) == 2, "Wrong Pos size"); |
| v = vdupq_n_u16(wsize); |
| |
| n = size / (sizeof(uint16x8_t) * 8); |
| do { |
| p0 = vld1q_u16_x4(table); |
| p1 = vld1q_u16_x4(table+32); |
| vqsubq_u16_x4_x1(p0, p0, v); |
| vqsubq_u16_x4_x1(p1, p1, v); |
| vst1q_u16_x4(table, p0); |
| vst1q_u16_x4(table+32, p1); |
| table += 64; |
| } while (--n); |
| } |
| |
| Z_INTERNAL void slide_hash_neon(deflate_state *s) { |
| unsigned int wsize = s->w_size; |
| |
| slide_hash_chain(s->head, HASH_SIZE, wsize); |
| slide_hash_chain(s->prev, wsize, wsize); |
| } |
| #endif |