| /* slide_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) |
| #ifdef _M_ARM64 |
| # include <arm64_neon.h> |
| #else |
| # include <arm_neon.h> |
| #endif |
| #include "../../zbuild.h" |
| #include "../../deflate.h" |
| |
| /* SIMD version of hash_chain rebase */ |
| static inline void slide_hash_chain(Pos *table, unsigned int entries, uint16_t window_size) { |
| Z_REGISTER uint16x8_t v, *p; |
| 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(window_size); |
| |
| p = (uint16x8_t *)table; |
| n = size / (sizeof(uint16x8_t) * 8); |
| do { |
| p[0] = vqsubq_u16(p[0], v); |
| p[1] = vqsubq_u16(p[1], v); |
| p[2] = vqsubq_u16(p[2], v); |
| p[3] = vqsubq_u16(p[3], v); |
| p[4] = vqsubq_u16(p[4], v); |
| p[5] = vqsubq_u16(p[5], v); |
| p[6] = vqsubq_u16(p[6], v); |
| p[7] = vqsubq_u16(p[7], v); |
| p += 8; |
| } 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 |