On Tue, 16 Aug 2022, Hubert Mazur wrote:
Provide optimized implementation of sse8 function for arm64.
Performance comparison tests are shown below.
- sse_1_c: 130.7
- sse_1_neon: 29.7
Benchmarks and tests run with checkasm tool on AWS Graviton 3.
Signed-off-by: Hubert Mazur <h...@semihalf.com>
---
libavcodec/aarch64/me_cmp_init_aarch64.c | 4 ++
libavcodec/aarch64/me_cmp_neon.S | 66 ++++++++++++++++++++++++
2 files changed, 70 insertions(+)
diff --git a/libavcodec/aarch64/me_cmp_init_aarch64.c
b/libavcodec/aarch64/me_cmp_init_aarch64.c
index 1c36d3d7cb..2f51f0497e 100644
--- a/libavcodec/aarch64/me_cmp_init_aarch64.c
+++ b/libavcodec/aarch64/me_cmp_init_aarch64.c
@@ -34,9 +34,12 @@ int ff_pix_abs16_y2_neon(MpegEncContext *v, const uint8_t
*pix1, const uint8_t *
int sse16_neon(MpegEncContext *v, const uint8_t *pix1, const uint8_t *pix2,
ptrdiff_t stride, int h);
+int sse8_neon(MpegEncContext *v, const uint8_t *pix1, const uint8_t *pix2,
+ ptrdiff_t stride, int h);
int sse4_neon(MpegEncContext *v, const uint8_t *pix1, const uint8_t *pix2,
ptrdiff_t stride, int h);
Same as the others about function declaration indentation
diff --git a/libavcodec/aarch64/me_cmp_neon.S b/libavcodec/aarch64/me_cmp_neon.S
index 0ec9c0465b..3f4266d4d5 100644
--- a/libavcodec/aarch64/me_cmp_neon.S
+++ b/libavcodec/aarch64/me_cmp_neon.S
@@ -347,6 +347,72 @@ function sse16_neon, export=1
ret
endfunc
+function sse8_neon, export=1
+ // x0 - unused
+ // x1 - pix1
+ // x2 - pix2
+ // x3 - stride
+ // w4 - h
+
+ movi d18, #0
Same as the others about d18
+ movi v21.4s, #0
+ movi v20.4s, #0
+ cmp w4, #4
+ b.le 2f
+
+// make 4 iterations at once
+1:
+
+ // res = abs(pix1[0] - pix2[0])
+ // res * res
+
+ ld1 {v0.8b}, [x1], x3 // Load pix1 for first
iteration
+ ld1 {v1.8b}, [x2], x3 // Load pix2 for
second iteration
+ ld1 {v2.8b}, [x1], x3 // Load pix1 for
second iteration
+ ld1 {v3.8b}, [x2], x3 // Load pix2 for
second iteration
+ uabdl v30.8h, v0.8b, v1.8b // Absolute
difference, first iteration
+ ld1 {v4.8b}, [x1], x3 // Load pix1 for third
iteration
+ ld1 {v5.8b}, [x2], x3 // Load pix2 for third
iteration
+ uabdl v29.8h, v2.8b, v3.8b // Absolute
difference, second iteration
+ umlal v21.4s, v30.4h, v30.4h // Multiply lower
half, first iteration
+ ld1 {v6.8b}, [x1], x3 // Load pix1 for
fourth iteration
+ ld1 {v7.8b}, [x2], x3 // Load pix2 for
fourth iteration
+ uabdl v28.8h, v4.8b, v5.8b // Absolute
difference, third iteration
+ umlal v21.4s, v29.4h, v29.4h // Multiply lower
half, second iteration
+ umlal2 v20.4s, v30.8h, v30.8h // Multiply upper
half, second iteration
The comment was wrong here, this is about the first iteration, not the
second one.
+ uabdl v27.8h, v6.8b, v7.8b // Absolute
difference, fourth iteration
+ umlal v21.4s, v28.4h, v28.4h // Multiply lower
half, third iteration
+ umlal2 v20.4s, v29.8h, v29.8h // Multiply upper
half, second iteration
+ sub w4, w4, #4 // h -= 4
+ umlal2 v20.4s, v28.8h, v28.8h // Multiply upper
half, third iteration
+ umlal v21.4s, v27.4h, v27.4h // Multiply lower
half, fourth iteration
+ cmp w4, #4
+ umlal2 v20.4s, v27.8h, v27.8h // Multiply upper
half, fourth iteration
+ b.ge 1b
+
+ cbz w4, 3f
+
+// iterate by one
+2:
+ ld1 {v0.8b}, [x1], x3 // Load pix1
+ ld1 {v1.8b}, [x2], x3 // Load pix2
+ subs w4, w4, #1
+ uabdl v30.8h, v0.8b, v1.8b
+ umlal v21.4s, v30.4h, v30.4h
+ umlal2 v20.4s, v30.8h, v30.8h
+
+ b.ne 2b
+
+3:
+ add v21.4s, v21.4s, v20.4s // Add accumulator
vectors together
+ uaddlv d17, v21.4s // Add up vector
+ add d18, d18, d17
+
Unnecesssary d18.
// Martin
_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
To unsubscribe, visit link above, or email
ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
