opencv/3rdparty/zlib-ng/arch/riscv/slide_hash_rvv.c
Letu Ren 0de26fd78e Add zlib-ng as an alternative zlib implementation
Zlib-ng is zlib replacement with optimizations for "next generation" systems. Its optimization may benifits image library decode and encode speed such as libpng. In our tests, if using zlib-ng and libpng combination on a x86_64 machine with AVX2, the time of `imdecode` amd `imencode` will drop 20% approximately. This patch enables zlib-ng's optimization if `CV_DISABLE_OPTIMIZATION` is OFF. Since Zlib-ng can dispatch intrinsics on the fly, port work is much easier.

Related discussion: https://github.com/opencv/opencv/issues/22573
2024-01-14 14:58:47 +08:00

35 lines
1.1 KiB
C

/* slide_hash_rvv.c - RVV version of slide_hash
* Copyright (C) 2023 SiFive, Inc. All rights reserved.
* Contributed by Alex Chiang <alex.chiang@sifive.com>
* For conditions of distribution and use, see copyright notice in zlib.h
*/
#ifdef RISCV_RVV
#include <riscv_vector.h>
#include "../../zbuild.h"
#include "../../deflate.h"
static inline void slide_hash_chain(Pos *table, uint32_t entries, uint16_t wsize) {
size_t vl;
while (entries > 0) {
vl = __riscv_vsetvl_e16m4(entries);
vuint16m4_t v_tab = __riscv_vle16_v_u16m4(table, vl);
vuint16m4_t v_diff = __riscv_vsub_vx_u16m4(v_tab, wsize, vl);
vbool4_t mask = __riscv_vmsltu_vx_u16m4_b4(v_tab, wsize, vl);
v_tab = __riscv_vmerge_vxm_u16m4(v_diff, 0, mask, vl);
__riscv_vse16_v_u16m4(table, v_tab, vl);
table += vl, entries -= vl;
}
}
Z_INTERNAL void slide_hash_rvv(deflate_state *s) {
uint16_t wsize = (uint16_t)s->w_size;
slide_hash_chain(s->head, HASH_SIZE, wsize);
slide_hash_chain(s->prev, wsize, wsize);
}
#endif // RISCV_RVV