opencv/3rdparty/zlib-ng/arch/arm/compare256_neon.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

60 lines
1.5 KiB
C

/* compare256_neon.c - NEON version of compare256
* Copyright (C) 2022 Nathan Moinvaziri
* For conditions of distribution and use, see copyright notice in zlib.h
*/
#include "../../zbuild.h"
#include "fallback_builtins.h"
#if defined(ARM_NEON) && defined(HAVE_BUILTIN_CTZLL)
#include "neon_intrins.h"
static inline uint32_t compare256_neon_static(const uint8_t *src0, const uint8_t *src1) {
uint32_t len = 0;
do {
uint8x16_t a, b, cmp;
uint64_t lane;
a = vld1q_u8(src0);
b = vld1q_u8(src1);
cmp = veorq_u8(a, b);
lane = vgetq_lane_u64(vreinterpretq_u64_u8(cmp), 0);
if (lane) {
uint32_t match_byte = (uint32_t)__builtin_ctzll(lane) / 8;
return len + match_byte;
}
len += 8;
lane = vgetq_lane_u64(vreinterpretq_u64_u8(cmp), 1);
if (lane) {
uint32_t match_byte = (uint32_t)__builtin_ctzll(lane) / 8;
return len + match_byte;
}
len += 8;
src0 += 16, src1 += 16;
} while (len < 256);
return 256;
}
Z_INTERNAL uint32_t compare256_neon(const uint8_t *src0, const uint8_t *src1) {
return compare256_neon_static(src0, src1);
}
#define LONGEST_MATCH longest_match_neon
#define COMPARE256 compare256_neon_static
#include "match_tpl.h"
#define LONGEST_MATCH_SLOW
#define LONGEST_MATCH longest_match_slow_neon
#define COMPARE256 compare256_neon_static
#include "match_tpl.h"
#endif