[FFmpeg-devel] [PATCH 2/4] lavc/aarch64: Provide neon implementation of nsse8
Grzegorz Bernacki
gjb at semihalf.com
Mon Sep 26 12:15:02 EEST 2022
Add vectorized implementation of nsse8 function.
Performance comparison tests are shown below.
- nsse_1_c: 256.0
- nsse_1_neon: 82.7
Benchmarks and tests run with checkasm tool on AWS Graviton 3.
Signed-off-by: Grzegorz Bernacki <gjb at semihalf.com>
---
libavcodec/aarch64/me_cmp_init_aarch64.c | 15 ++++
libavcodec/aarch64/me_cmp_neon.S | 99 ++++++++++++++++++++++++
2 files changed, 114 insertions(+)
diff --git a/libavcodec/aarch64/me_cmp_init_aarch64.c b/libavcodec/aarch64/me_cmp_init_aarch64.c
index 3459403ee5..2c61cfcf63 100644
--- a/libavcodec/aarch64/me_cmp_init_aarch64.c
+++ b/libavcodec/aarch64/me_cmp_init_aarch64.c
@@ -66,6 +66,11 @@ int ff_pix_abs8_y2_neon(MpegEncContext *v, const uint8_t *pix1, const uint8_t *p
int ff_pix_abs8_xy2_neon(MpegEncContext *v, const uint8_t *pix1, const uint8_t *pix2,
ptrdiff_t stride, int h);
+int nsse8_neon(int multiplier, const uint8_t *s, const uint8_t *s2,
+ ptrdiff_t stride, int h);
+int nsse8_neon_wrapper(MpegEncContext *c, const uint8_t *s1, const uint8_t *s2,
+ ptrdiff_t stride, int h);
+
av_cold void ff_me_cmp_init_aarch64(MECmpContext *c, AVCodecContext *avctx)
{
int cpu_flags = av_get_cpu_flags();
@@ -94,6 +99,7 @@ av_cold void ff_me_cmp_init_aarch64(MECmpContext *c, AVCodecContext *avctx)
c->vsse[4] = vsse_intra16_neon;
c->nsse[0] = nsse16_neon_wrapper;
+ c->nsse[1] = nsse8_neon_wrapper;
c->median_sad[0] = pix_median_abs16_neon;
c->median_sad[1] = pix_median_abs8_neon;
@@ -108,3 +114,12 @@ int nsse16_neon_wrapper(MpegEncContext *c, const uint8_t *s1, const uint8_t *s2,
else
return nsse16_neon(8, s1, s2, stride, h);
}
+
+int nsse8_neon_wrapper(MpegEncContext *c, const uint8_t *s1, const uint8_t *s2,
+ ptrdiff_t stride, int h)
+{
+ if (c)
+ return nsse8_neon(c->avctx->nsse_weight, s1, s2, stride, h);
+ else
+ return nsse8_neon(8, s1, s2, stride, h);
+}
diff --git a/libavcodec/aarch64/me_cmp_neon.S b/libavcodec/aarch64/me_cmp_neon.S
index e03c0c26cd..6f7c7c1690 100644
--- a/libavcodec/aarch64/me_cmp_neon.S
+++ b/libavcodec/aarch64/me_cmp_neon.S
@@ -1163,6 +1163,105 @@ function nsse16_neon, export=1
ret
endfunc
+function nsse8_neon, export=1
+ // x0 multiplier
+ // x1 uint8_t *pix1
+ // x2 uint8_t *pix2
+ // x3 ptrdiff_t stride
+ // w4 int h
+
+ str x0, [sp, #-0x40]!
+ stp x1, x2, [sp, #0x10]
+ stp x3, x4, [sp, #0x20]
+ str x30, [sp, #0x30]
+ bl X(sse8_neon)
+ ldr x30, [sp, #0x30]
+ mov w9, w0 // here we store score1
+ ldr x5, [sp]
+ ldp x1, x2, [sp, #0x10]
+ ldp x3, x4, [sp, #0x20]
+ add sp, sp, #0x40
+
+ movi v16.8h, #0
+ movi v17.8h, #0
+ movi v18.8h, #0
+ movi v19.8h, #0
+
+ ld1 {v0.8b}, [x1], x3
+ subs w4, w4, #1 // we need to make h-1 iterations
+ ext v1.8b, v0.8b, v0.8b, #1 // x1 + 1
+ ld1 {v2.8b}, [x2], x3
+ cmp w4, #2
+ ext v3.8b, v2.8b, v2.8b, #1 // x2 + 1
+
+ b.lt 2f
+
+// make 2 iterations at once
+1:
+ ld1 {v4.8b}, [x1], x3
+ ld1 {v20.8b}, [x1], x3
+ ld1 {v6.8b}, [x2], x3
+ ext v5.8b, v4.8b, v4.8b, #1 // x1 + stride + 1
+ ext v21.8b, v20.8b, v20.8b, #1
+ ld1 {v22.8b}, [x2], x3
+ ext v7.8b, v6.8b, v6.8b, #1 // x2 + stride + 1
+ usubl v31.8h, v0.8b, v4.8b
+ ext v23.8b, v22.8b, v22.8b, #1
+ usubl v29.8h, v1.8b, v5.8b
+ usubl v27.8h, v2.8b, v6.8b
+ usubl v25.8h, v3.8b, v7.8b
+ saba v16.8h, v31.8h, v29.8h
+ usubl v31.8h, v4.8b, v20.8b
+ saba v18.8h, v27.8h, v25.8h
+ sub w4, w4, #2
+ usubl v29.8h, v5.8b, v21.8b
+ mov v0.16b, v20.16b
+ mov v1.16b, v21.16b
+ saba v16.8h, v31.8h, v29.8h
+ usubl v27.8h, v6.8b, v22.8b
+ usubl v25.8h, v7.8b, v23.8b
+ mov v2.16b, v22.16b
+ mov v3.16b, v23.16b
+ cmp w4, #2
+ saba v18.8h, v27.8h, v25.8h
+ b.ge 1b
+ cbz w4, 3f
+
+// iterate by one
+2:
+ ld1 {v4.8b}, [x1], x3
+ subs w4, w4, #1
+ ext v5.8b, v4.8b, v4.8b, #1 // x1 + stride + 1
+ ld1 {v6.8b}, [x2], x3
+ usubl v31.8h, v0.8b, v4.8b
+ ext v7.8b, v6.8b, v6.8b, #1 // x2 + stride + 1
+
+ usubl v29.8h, v1.8b, v5.8b
+ saba v16.8h, v31.8h, v29.8h
+ usubl v27.8h, v2.8b, v6.8b
+ usubl v25.8h, v3.8b, v7.8b
+ saba v18.8h, v27.8h, v25.8h
+
+ mov v0.16b, v4.16b
+ mov v1.16b, v5.16b
+ mov v2.16b, v6.16b
+ mov v3.16b, v7.16b
+
+ cbnz w4, 2b
+
+3:
+ sqsub v16.8h, v16.8h, v18.8h
+ ins v16.h[7], wzr
+ saddlv s16, v16.8h
+ sqabs s16, s16
+ fmov w0, s16
+
+ mul w0, w0, w5
+ add w0, w0, w9
+
+ ret
+endfunc
+
function pix_median_abs16_neon, export=1
// x0 unused
// x1 uint8_t *pix1
--
2.25.1
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