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lavc/aarch64: Add neon implementation for sse4

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Provide neon implementation for sse4 function.

Performance comparison tests are shown below.
- sse_2_c: 80.7
- sse_2_neon: 31.0

Benchmarks and tests are run with checkasm tool on AWS Graviton 3.

Signed-off-by: Hubert Mazur <hum@semihalf.com>
Signed-off-by: Martin Storsjö <martin@martin.st>
This commit is contained in:
Hubert Mazur 2022-08-16 14:20:13 +02:00 committed by Martin Storsjö
parent ad251fd262
commit d7abb7d143
2 changed files with 59 additions and 0 deletions
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3
libavcodec/aarch64/me_cmp_init_aarch64.c
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@ -32,6 +32,8 @@ int ff_pix_abs16_x2_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 sse4_neon(MpegEncContext *v, const uint8_t *pix1, const uint8_t *pix2,
ptrdiff_t stride, int h);
av_cold void ff_me_cmp_init_aarch64(MECmpContext *c, AVCodecContext *avctx)
{
@ -44,5 +46,6 @@ av_cold void ff_me_cmp_init_aarch64(MECmpContext *c, AVCodecContext *avctx)
c->sad[0] = ff_pix_abs16_neon;
c->sse[0] = sse16_neon;
c->sse[2] = sse4_neon;
}
}

56
libavcodec/aarch64/me_cmp_neon.S
View File

@ -344,3 +344,59 @@ function sse16_neon, export=1
ret
endfunc
function sse4_neon, export=1
// x0 - unused
// x1 - pix1
// x2 - pix2
// x3 - stride
// w4 - h
movi v16.4s, #0 // clear the result accumulator
cmp w4, #4
b.le 2f
// make 4 iterations at once
1:
// res = abs(pix1[0] - pix2[0])
// res * res
ld1 {v0.s}[0], [x1], x3 // Load pix1, first iteration
ld1 {v1.s}[0], [x2], x3 // Load pix2, first iteration
ld1 {v2.s}[0], [x1], x3 // Load pix1, second iteration
ld1 {v3.s}[0], [x2], x3 // Load pix2, second iteration
uabdl v30.8h, v0.8b, v1.8b // Absolute difference, first iteration
ld1 {v4.s}[0], [x1], x3 // Load pix1, third iteration
ld1 {v5.s}[0], [x2], x3 // Load pix2, third iteration
uabdl v29.8h, v2.8b, v3.8b // Absolute difference, second iteration
umlal v16.4s, v30.4h, v30.4h // Multiply vectors, first iteration
ld1 {v6.s}[0], [x1], x3 // Load pix1, fourth iteration
ld1 {v7.s}[0], [x2], x3 // Load pix2, fourth iteration
uabdl v28.8h, v4.8b, v5.8b // Absolute difference, third iteration
umlal v16.4s, v29.4h, v29.4h // Multiply and accumulate, second iteration
sub w4, w4, #4
uabdl v27.8h, v6.8b, v7.8b // Absolue difference, fourth iteration
umlal v16.4s, v28.4h, v28.4h // Multiply and accumulate, third iteration
cmp w4, #4
umlal v16.4s, v27.4h, v27.4h // Multiply and accumulate, fourth iteration
b.ge 1b
cbz w4, 3f
// iterate by one
2:
ld1 {v0.s}[0], [x1], x3 // Load pix1
ld1 {v1.s}[0], [x2], x3 // Load pix2
uabdl v30.8h, v0.8b, v1.8b
subs w4, w4, #1
umlal v16.4s, v30.4h, v30.4h
b.ne 2b
3:
uaddlv d17, v16.4s // Add vector
fmov w0, s17
ret
endfunc