[FFmpeg-devel] [PATCH v2 4/5] libswscale: Enable hscale_avx2 for all input sizes.

[Alan Kelly]

Hi Michael,

Thanks for looking at this. I fixed the test issue.

Alan

On Fri, Jul 15, 2022 at 4:59 PM Alan Kelly <alankelly at google.com> wrote:

> ff_shuffle_filter_coefficients shuffles the tail as required.
> ---
>  libswscale/utils.c        | 19 ++++++++++++++++---
>  libswscale/x86/swscale.c  |  6 ++----
>  tests/checkasm/sw_scale.c |  2 +-
>  3 files changed, 19 insertions(+), 8 deletions(-)
>
> diff --git a/libswscale/utils.c b/libswscale/utils.c
> index cb4f5b521c..544b7fee96 100644
> --- a/libswscale/utils.c
> +++ b/libswscale/utils.c
> @@ -266,8 +266,7 @@ int ff_shuffle_filter_coefficients(SwsContext *c, int
> *filterPos,
>  #if ARCH_X86_64
>      int i, j, k;
>      int cpu_flags = av_get_cpu_flags();
> -    // avx2 hscale filter processes 16 pixel blocks.
> -    if (!filter || dstW % 16 != 0)
> +    if (!filter)
>          return 0;
>      if (EXTERNAL_AVX2_FAST(cpu_flags) && !(cpu_flags &
> AV_CPU_FLAG_SLOW_GATHER)) {
>          if ((c->srcBpc == 8) && (c->dstBpc <= 14)) {
> @@ -279,9 +278,11 @@ int ff_shuffle_filter_coefficients(SwsContext *c, int
> *filterPos,
>             }
>             // Do not swap filterPos for pixels which won't be processed by
>             // the main loop.
> -           for (i = 0; i + 8 <= dstW; i += 8) {
> +           for (i = 0; i + 16 <= dstW; i += 16) {
>                 FFSWAP(int, filterPos[i + 2], filterPos[i + 4]);
>                 FFSWAP(int, filterPos[i + 3], filterPos[i + 5]);
> +               FFSWAP(int, filterPos[i + 10], filterPos[i + 12]);
> +               FFSWAP(int, filterPos[i + 11], filterPos[i + 13]);
>             }
>             if (filterSize > 4) {
>                 // 16 pixels are processed at a time.
> @@ -295,6 +296,18 @@ int ff_shuffle_filter_coefficients(SwsContext *c, int
> *filterPos,
>                         }
>                     }
>                 }
> +               // 4 pixels are processed at a time in the tail.
> +               for (; i < dstW; i += 4) {
> +                   // 4 filter coeffs are processed at a time.
> +                   int rem = dstW - i >= 4 ? 4 : dstW - i;
> +                   for (k = 0; k + 4 <= filterSize; k += 4) {
> +                       for (j = 0; j < rem; ++j) {
> +                           int from = (i + j) * filterSize + k;
> +                           int to = i * filterSize + j * 4 + k * 4;
> +                           memcpy(&filter[to], &filterCopy[from], 4 *
> sizeof(int16_t));
> +                       }
> +                   }
> +               }
>             }
>             av_free(filterCopy);
>          }
> diff --git a/libswscale/x86/swscale.c b/libswscale/x86/swscale.c
> index 628f12137c..f628c71bd4 100644
> --- a/libswscale/x86/swscale.c
> +++ b/libswscale/x86/swscale.c
> @@ -626,10 +626,8 @@ switch(c->dstBpc){ \
>
>      if (EXTERNAL_AVX2_FAST(cpu_flags) && !(cpu_flags &
> AV_CPU_FLAG_SLOW_GATHER)) {
>          if ((c->srcBpc == 8) && (c->dstBpc <= 14)) {
> -            if (c->chrDstW % 16 == 0)
> -                ASSIGN_AVX2_SCALE_FUNC(c->hcScale, c->hChrFilterSize);
> -            if (c->dstW % 16 == 0)
> -                ASSIGN_AVX2_SCALE_FUNC(c->hyScale, c->hLumFilterSize);
> +            ASSIGN_AVX2_SCALE_FUNC(c->hcScale, c->hChrFilterSize);
> +            ASSIGN_AVX2_SCALE_FUNC(c->hyScale, c->hLumFilterSize);
>          }
>      }
>
> diff --git a/tests/checkasm/sw_scale.c b/tests/checkasm/sw_scale.c
> index b643a47c30..798990a6cf 100644
> --- a/tests/checkasm/sw_scale.c
> +++ b/tests/checkasm/sw_scale.c
> @@ -223,7 +223,7 @@ static void check_hscale(void)
>                  ff_sws_init_scale(ctx);
>                  memcpy(filterAvx2, filter, sizeof(uint16_t) * (SRC_PIXELS
> * MAX_FILTER_WIDTH + MAX_FILTER_WIDTH));
>                  if ((cpu_flags & AV_CPU_FLAG_AVX2) && !(cpu_flags &
> AV_CPU_FLAG_SLOW_GATHER))
> -                    ff_shuffle_filter_coefficients(ctx, filterPosAvx,
> width, filterAvx2, SRC_PIXELS);
> +                    ff_shuffle_filter_coefficients(ctx, filterPosAvx,
> width, filterAvx2, ctx->dstW);
>
>                  if (check_func(ctx->hcScale,
> "hscale_%d_to_%d__fs_%d_dstW_%d", ctx->srcBpc, ctx->dstBpc + 1, width,
> ctx->dstW)) {
>                      memset(dst0, 0, SRC_PIXELS * sizeof(dst0[0]));
> --
> 2.37.0.170.g444d1eabd0-goog
>
>