[FFmpeg-devel] [PATCH] avcodec/x86/mpegvideoenc_template: Disable dead code

[Andreas Rheinhardt]

Andreas Rheinhardt:
> Since bfb28b5ce89f3e950214b67ea95b45e3355c2caf the permutation
> type FF_IDCT_PERM_SIMPLE is ARCH_X86_32-only. So use this
> knowledge to disable code for it when not on ARCH_X86_32.
> 
> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
> ---
>  libavcodec/x86/idctdsp_init.c          | 2 ++
>  libavcodec/x86/mpegvideoenc_template.c | 3 ++-
>  2 files changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/libavcodec/x86/idctdsp_init.c b/libavcodec/x86/idctdsp_init.c
> index f28a1ad744..2d165b975b 100644
> --- a/libavcodec/x86/idctdsp_init.c
> +++ b/libavcodec/x86/idctdsp_init.c
> @@ -45,10 +45,12 @@ av_cold int ff_init_scantable_permutation_x86(uint8_t *idct_permutation,
>      int i;
>  
>      switch (perm_type) {
> +#if ARCH_X86_32
>      case FF_IDCT_PERM_SIMPLE:
>          for (i = 0; i < 64; i++)
>              idct_permutation[i] = simple_mmx_permutation[i];
>          return 1;
> +#endif
>      case FF_IDCT_PERM_SSE2:
>          for (i = 0; i < 64; i++)
>              idct_permutation[i] = (i & 0x38) | idct_sse2_row_perm[i & 7];
> diff --git a/libavcodec/x86/mpegvideoenc_template.c b/libavcodec/x86/mpegvideoenc_template.c
> index b5b0a5ffa2..5f013be7f5 100644
> --- a/libavcodec/x86/mpegvideoenc_template.c
> +++ b/libavcodec/x86/mpegvideoenc_template.c
> @@ -225,7 +225,8 @@ static int RENAME(dct_quantize)(MpegEncContext *s,
>      if(s->mb_intra) block[0]= level;
>      else            block[0]= temp_block[0];
>  
> -    if (s->idsp.perm_type == FF_IDCT_PERM_SIMPLE) {
> +    av_assert2(ARCH_X86_32 || s->idsp.perm_type != FF_IDCT_PERM_SIMPLE);
> +    if (ARCH_X86_32 && s->idsp.perm_type == FF_IDCT_PERM_SIMPLE) {
>          if(last_non_zero_p1 <= 1) goto end;
>          block[0x08] = temp_block[0x01]; block[0x10] = temp_block[0x08];
>          block[0x20] = temp_block[0x10];

Will apply this patch tomorrow unless there are objections.

- Andreas