mirror of
https://chromium.googlesource.com/libyuv/libyuv
synced 2025-12-08 01:36:47 +08:00
53b65220da
The Neon dot-product instructions perform two widening steps rather than one, saving us the need to widen the absolute difference to 16-bits before accumulating. Additionally, the dot-product instructions tend to have better performance characteristics than traditional widening multiply instructions like SMLAL used in the existing SumSquareError_NEON code. Observed reduction in runtimes compared to the existing Neon kernel: Cortex-A55: -9.1% Cortex-A510: -36.7% Cortex-A76: -37.6% Cortex-A720: -48.8% Cortex-X1: -56.1% Cortex-X2: -42.6% Bug: libyuv:977 Change-Id: Ie20c69040cc47a803d8e95620d31e0bf1e1dac12 Reviewed-on: https://chromium-review.googlesource.com/c/libyuv/libyuv/+/5463945 Reviewed-by: Frank Barchard <fbarchard@chromium.org>
120 lines
4.4 KiB
C++
120 lines
4.4 KiB
C++
/*
|
|
* Copyright 2012 The LibYuv Project Authors. All rights reserved.
|
|
*
|
|
* Use of this source code is governed by a BSD-style license
|
|
* that can be found in the LICENSE file in the root of the source
|
|
* tree. An additional intellectual property rights grant can be found
|
|
* in the file PATENTS. All contributing project authors may
|
|
* be found in the AUTHORS file in the root of the source tree.
|
|
*/
|
|
|
|
#include "libyuv/basic_types.h"
|
|
|
|
#include "libyuv/compare_row.h"
|
|
#include "libyuv/row.h"
|
|
|
|
#ifdef __cplusplus
|
|
namespace libyuv {
|
|
extern "C" {
|
|
#endif
|
|
|
|
#if !defined(LIBYUV_DISABLE_NEON) && defined(__aarch64__)
|
|
|
|
// 256 bits at a time
|
|
// uses short accumulator which restricts count to 131 KB
|
|
uint32_t HammingDistance_NEON(const uint8_t* src_a,
|
|
const uint8_t* src_b,
|
|
int count) {
|
|
uint32_t diff;
|
|
asm volatile(
|
|
"movi v4.8h, #0 \n"
|
|
|
|
"1: \n"
|
|
"ld1 {v0.16b, v1.16b}, [%0], #32 \n"
|
|
"ld1 {v2.16b, v3.16b}, [%1], #32 \n"
|
|
"eor v0.16b, v0.16b, v2.16b \n"
|
|
"prfm pldl1keep, [%0, 448] \n" // prefetch 7 lines ahead
|
|
"eor v1.16b, v1.16b, v3.16b \n"
|
|
"cnt v0.16b, v0.16b \n"
|
|
"prfm pldl1keep, [%1, 448] \n"
|
|
"cnt v1.16b, v1.16b \n"
|
|
"subs %w2, %w2, #32 \n"
|
|
"add v0.16b, v0.16b, v1.16b \n"
|
|
"uadalp v4.8h, v0.16b \n"
|
|
"b.gt 1b \n"
|
|
|
|
"uaddlv s4, v4.8h \n"
|
|
"fmov %w3, s4 \n"
|
|
: "+r"(src_a), "+r"(src_b), "+r"(count), "=r"(diff)
|
|
:
|
|
: "memory", "cc", "v0", "v1", "v2", "v3", "v4");
|
|
return diff;
|
|
}
|
|
|
|
uint32_t SumSquareError_NEON(const uint8_t* src_a,
|
|
const uint8_t* src_b,
|
|
int count) {
|
|
uint32_t sse;
|
|
asm volatile(
|
|
"movi v16.16b, #0 \n"
|
|
"movi v17.16b, #0 \n"
|
|
"movi v18.16b, #0 \n"
|
|
"movi v19.16b, #0 \n"
|
|
|
|
"1: \n"
|
|
"ld1 {v0.16b}, [%0], #16 \n"
|
|
"ld1 {v1.16b}, [%1], #16 \n"
|
|
"subs %w2, %w2, #16 \n"
|
|
"usubl v2.8h, v0.8b, v1.8b \n"
|
|
"usubl2 v3.8h, v0.16b, v1.16b \n"
|
|
"prfm pldl1keep, [%0, 448] \n" // prefetch 7 lines ahead
|
|
"smlal v16.4s, v2.4h, v2.4h \n"
|
|
"smlal v17.4s, v3.4h, v3.4h \n"
|
|
"prfm pldl1keep, [%1, 448] \n"
|
|
"smlal2 v18.4s, v2.8h, v2.8h \n"
|
|
"smlal2 v19.4s, v3.8h, v3.8h \n"
|
|
"b.gt 1b \n"
|
|
|
|
"add v16.4s, v16.4s, v17.4s \n"
|
|
"add v18.4s, v18.4s, v19.4s \n"
|
|
"add v19.4s, v16.4s, v18.4s \n"
|
|
"addv s0, v19.4s \n"
|
|
"fmov %w3, s0 \n"
|
|
: "+r"(src_a), "+r"(src_b), "+r"(count), "=r"(sse)
|
|
:
|
|
: "memory", "cc", "v0", "v1", "v2", "v3", "v16", "v17", "v18", "v19");
|
|
return sse;
|
|
}
|
|
|
|
uint32_t SumSquareError_NEON_DotProd(const uint8_t* src_a,
|
|
const uint8_t* src_b,
|
|
int count) {
|
|
uint32_t sse;
|
|
asm volatile(
|
|
"movi v2.16b, #0 \n"
|
|
|
|
"1: \n"
|
|
"ld1 {v0.16b}, [%0], #16 \n"
|
|
"ld1 {v1.16b}, [%1], #16 \n"
|
|
"subs %w2, %w2, #16 \n"
|
|
"uabd v0.16b, v0.16b, v1.16b \n"
|
|
"prfm pldl1keep, [%0, 448] \n" // prefetch 7 lines ahead
|
|
"udot v2.4s, v0.16b, v0.16b \n"
|
|
"prfm pldl1keep, [%1, 448] \n"
|
|
"b.gt 1b \n"
|
|
|
|
"addv s0, v2.4s \n"
|
|
"fmov %w3, s0 \n"
|
|
: "+r"(src_a), "+r"(src_b), "+r"(count), "=r"(sse)
|
|
:
|
|
: "memory", "cc", "v0", "v1", "v2");
|
|
return sse;
|
|
}
|
|
|
|
#endif // !defined(LIBYUV_DISABLE_NEON) && defined(__aarch64__)
|
|
|
|
#ifdef __cplusplus
|
|
} // extern "C"
|
|
} // namespace libyuv
|
|
#endif
|