| Message ID | 20220816122016.64929-4-hum@semihalf.com |
|---|---|
| State | New |
| Headers | show |
| Series | Provide neon implementation for me_cmp functions | expand |
| Context | Check | Description |
|---|---|---|
| yinshiyou/make_loongarch64 | success | Make finished |
| yinshiyou/make_fate_loongarch64 | success | Make fate finished |
| andriy/make_x86 | success | Make finished |
| andriy/make_fate_x86 | success | Make fate finished |
On Tue, 16 Aug 2022, Hubert Mazur wrote: > Provide optimized implementation of pix_abs16_y2 function for arm64. > > Performance comparison tests are shown below. > pix_abs_0_2_c: 317.2 > pix_abs_0_2_neon: 37.5 > > Benchmarks and tests run with checkasm tool on AWS Graviton 3. > > Signed-off-by: Hubert Mazur <hum@semihalf.com> > --- > libavcodec/aarch64/me_cmp_init_aarch64.c | 3 + > libavcodec/aarch64/me_cmp_neon.S | 75 ++++++++++++++++++++++++ > 2 files changed, 78 insertions(+) > > diff --git a/libavcodec/aarch64/me_cmp_init_aarch64.c b/libavcodec/aarch64/me_cmp_init_aarch64.c > index 955592625a..1c36d3d7cb 100644 > --- a/libavcodec/aarch64/me_cmp_init_aarch64.c > +++ b/libavcodec/aarch64/me_cmp_init_aarch64.c > @@ -29,6 +29,8 @@ int ff_pix_abs16_xy2_neon(MpegEncContext *s, const uint8_t *blk1, const uint8_t > ptrdiff_t stride, int h); > int ff_pix_abs16_x2_neon(MpegEncContext *v, const uint8_t *pix1, const uint8_t *pix2, > ptrdiff_t stride, int h); > +int ff_pix_abs16_y2_neon(MpegEncContext *v, const uint8_t *pix1, const uint8_t *pix2, > + ptrdiff_t stride, int h); Misaligned function declaration. > diff --git a/libavcodec/aarch64/me_cmp_neon.S b/libavcodec/aarch64/me_cmp_neon.S > index 367924b3c2..0ec9c0465b 100644 > --- a/libavcodec/aarch64/me_cmp_neon.S > +++ b/libavcodec/aarch64/me_cmp_neon.S > @@ -404,3 +404,78 @@ function sse4_neon, export=1 > > ret > endfunc > + > +function ff_pix_abs16_y2_neon, export=1 Why place this new function at the bottom of the file, instead of logically following the other preexisting pix_abs16 function? In the version I pushed, I moved it further up > + // x0 unused > + // x1 uint8_t *pix1 > + // x2 uint8_t *pix2 > + // x3 ptrdiff_t stride > + // x4 int h This should be w4. You had fixed this in a couple patches, but missed this one. > + > + // initialize buffers > + movi v29.8h, #0 // clear the accumulator > + movi v28.8h, #0 // clear the accumulator > + movi d18, #0 Unused d18 here too > + add x5, x2, x3 // pix2 + stride > + cmp w4, #4 > + b.lt 2f > + > +// make 4 iterations at once > +1: > + > + // abs(pix1[0], avg2(pix2[0], pix2[0 + stride])) > + // avg2(a, b) = (((a) + (b) + 1) >> 1) > + // abs(x) = (x < 0 ? (-x) : (x)) > + > + ld1 {v1.16b}, [x2], x3 // Load pix2 for first iteration > + ld1 {v2.16b}, [x5], x3 // Load pix3 for first iteration > + urhadd v30.16b, v1.16b, v2.16b // Rounding halving add, first iteration > + ld1 {v0.16b}, [x1], x3 // Load pix1 for first iteration > + uabal v29.8h, v0.8b, v30.8b // Absolute difference of lower half, first iteration This whole first sequence is almost entirely blocking, waiting for the result of the previous operation - did you miss to interleave this with the rest of the operations? Normally I wouldn't bother with minor interleaving details, but here the impact was rather big. I manually reinterleaved the whole function, and got this speedup: Before: Cortex A53 A72 A73 pix_abs_0_2_neon: 153.0 63.7 52.7 After: pix_abs_0_2_neon: 141.0 61.7 51.7 // Martin
diff --git a/libavcodec/aarch64/me_cmp_init_aarch64.c b/libavcodec/aarch64/me_cmp_init_aarch64.c index 955592625a..1c36d3d7cb 100644 --- a/libavcodec/aarch64/me_cmp_init_aarch64.c +++ b/libavcodec/aarch64/me_cmp_init_aarch64.c @@ -29,6 +29,8 @@ int ff_pix_abs16_xy2_neon(MpegEncContext *s, const uint8_t *blk1, const uint8_t ptrdiff_t stride, int h); int ff_pix_abs16_x2_neon(MpegEncContext *v, const uint8_t *pix1, const uint8_t *pix2, ptrdiff_t stride, int h); +int ff_pix_abs16_y2_neon(MpegEncContext *v, const uint8_t *pix1, const uint8_t *pix2, + ptrdiff_t stride, int h); int sse16_neon(MpegEncContext *v, const uint8_t *pix1, const uint8_t *pix2, ptrdiff_t stride, int h); @@ -42,6 +44,7 @@ av_cold void ff_me_cmp_init_aarch64(MECmpContext *c, AVCodecContext *avctx) if (have_neon(cpu_flags)) { c->pix_abs[0][0] = ff_pix_abs16_neon; c->pix_abs[0][1] = ff_pix_abs16_x2_neon; + c->pix_abs[0][2] = ff_pix_abs16_y2_neon; c->pix_abs[0][3] = ff_pix_abs16_xy2_neon; c->sad[0] = ff_pix_abs16_neon; diff --git a/libavcodec/aarch64/me_cmp_neon.S b/libavcodec/aarch64/me_cmp_neon.S index 367924b3c2..0ec9c0465b 100644 --- a/libavcodec/aarch64/me_cmp_neon.S +++ b/libavcodec/aarch64/me_cmp_neon.S @@ -404,3 +404,78 @@ function sse4_neon, export=1 ret endfunc + +function ff_pix_abs16_y2_neon, export=1 + // x0 unused + // x1 uint8_t *pix1 + // x2 uint8_t *pix2 + // x3 ptrdiff_t stride + // x4 int h + + // initialize buffers + movi v29.8h, #0 // clear the accumulator + movi v28.8h, #0 // clear the accumulator + movi d18, #0 + add x5, x2, x3 // pix2 + stride + cmp w4, #4 + b.lt 2f + +// make 4 iterations at once +1: + + // abs(pix1[0], avg2(pix2[0], pix2[0 + stride])) + // avg2(a, b) = (((a) + (b) + 1) >> 1) + // abs(x) = (x < 0 ? (-x) : (x)) + + ld1 {v1.16b}, [x2], x3 // Load pix2 for first iteration + ld1 {v2.16b}, [x5], x3 // Load pix3 for first iteration + urhadd v30.16b, v1.16b, v2.16b // Rounding halving add, first iteration + ld1 {v0.16b}, [x1], x3 // Load pix1 for first iteration + uabal v29.8h, v0.8b, v30.8b // Absolute difference of lower half, first iteration + ld1 {v4.16b}, [x2], x3 // Load pix2 for second iteration + uabal2 v28.8h, v0.16b, v30.16b // Absolute difference of upper half, first iteration + ld1 {v5.16b}, [x5], x3 // Load pix3 for second iteartion + urhadd v27.16b, v4.16b, v5.16b // Rounding halving add, second iteration + ld1 {v3.16b}, [x1], x3 // Load pix1 for second iteration + uabal v29.8h, v3.8b, v27.8b // Absolute difference of lower half for second iteration + ld1 {v7.16b}, [x2], x3 // Load pix2 for third iteration + ld1 {v20.16b}, [x5], x3 // Load pix3 for third iteration + uabal2 v28.8h, v3.16b, v27.16b // Absolute difference of upper half for second iteration + ld1 {v6.16b}, [x1], x3 // Load pix1 for third iteration + urhadd v26.16b, v7.16b, v20.16b // Rounding halving add, third iteration + uabal v29.8h, v6.8b, v26.8b // Absolute difference of lower half for third iteration + ld1 {v22.16b}, [x2], x3 // Load pix2 for fourth iteration + uabal2 v28.8h, v6.16b, v26.16b // Absolute difference of upper half for third iteration + ld1 {v23.16b}, [x5], x3 // Load pix3 for fourth iteration + sub w4, w4, #4 // h-= 4 + urhadd v25.16b, v22.16b, v23.16b // Rounding halving add + ld1 {v21.16b}, [x1], x3 // Load pix1 for fourth iteration + cmp w4, #4 + uabal v29.8h, v21.8b, v25.8b // Absolute difference of lower half for fourth iteration + uabal2 v28.8h, v21.16b, v25.16b // Absolute difference of upper half for fourth iteration + + b.ge 1b + cbz w4, 3f + +// iterate by one +2: + + ld1 {v1.16b}, [x2], x3 // Load pix2 + ld1 {v2.16b}, [x5], x3 // Load pix3 + subs w4, w4, #1 + urhadd v30.16b, v1.16b, v2.16b // Rounding halving add + ld1 {v0.16b}, [x1], x3 // Load pix1 + uabal v29.8h, v30.8b, v0.8b + uabal2 v28.8h, v30.16b, v0.16b + + b.ne 2b + +3: + add v29.8h, v29.8h, v28.8h // Add vectors together + uaddlv s16, v29.8h // Add up vector values + add d18, d18, d16 + + fmov w0, s18 + + ret +endfunc
Provide optimized implementation of pix_abs16_y2 function for arm64. Performance comparison tests are shown below. pix_abs_0_2_c: 317.2 pix_abs_0_2_neon: 37.5 Benchmarks and tests run with checkasm tool on AWS Graviton 3. Signed-off-by: Hubert Mazur <hum@semihalf.com> --- libavcodec/aarch64/me_cmp_init_aarch64.c | 3 + libavcodec/aarch64/me_cmp_neon.S | 75 ++++++++++++++++++++++++ 2 files changed, 78 insertions(+)