[FFmpeg-devel] [PATCH 3/9] x86: prores: templatize 10 bits simple_idct

Ronald S. Bultje rsbultje at gmail.com
Tue Oct 13 01:48:32 CEST 2015


Hi,

On Mon, Oct 12, 2015 at 1:37 PM, Christophe Gisquet <
christophe.gisquet at gmail.com> wrote:

> This should be reused for a generic simple_idct10 function.
> Requires a bit of trickery to declare common constants in C.
> ---
>  libavcodec/x86/constants.c                |  28 +++
>  libavcodec/x86/constants.h                |  16 ++
>  libavcodec/x86/proresdsp.asm              | 263 +-------------------------
>  libavcodec/x86/simple_idct10_template.asm | 299
> ++++++++++++++++++++++++++++++
>  4 files changed, 346 insertions(+), 260 deletions(-)
>  create mode 100644 libavcodec/x86/simple_idct10_template.asm
>
> diff --git a/libavcodec/x86/constants.c b/libavcodec/x86/constants.c
> index 3f3ee0f..9592fa7 100644
> --- a/libavcodec/x86/constants.c
> +++ b/libavcodec/x86/constants.c
> @@ -87,3 +87,31 @@ DECLARE_ALIGNED(32, const ymm_reg,  ff_pd_32)   = {
> 0x0000002000000020ULL, 0x000
>
>  0x0000002000000020ULL, 0x0000002000000020ULL };
>  DECLARE_ALIGNED(32, const ymm_reg,  ff_pd_65535)= {
> 0x0000ffff0000ffffULL, 0x0000ffff0000ffffULL,
>
>  0x0000ffff0000ffffULL, 0x0000ffff0000ffffULL };
> +
> +/* simple idct 10 */
> +#define W1sh2 22725 // W1 = 90901 = 22725<<2 + 1
> +#define W2sh2 21407 // W2 = 85627 = 21407<<2 - 1
> +#define W3sh2 19265 // W3 = 77062 = 19265<<2 + 2
> +#define W4sh2 16384 // W4 = 65535 = 16384<<2 - 1
> +#define W5sh2 12873 // W5 = 51491 = 12873<<2 - 1
> +#define W6sh2  8867 // W6 = 35468 =  8867<<2
> +#define W7sh2  4520 // W7 = 18081 =  4520<<2 + 1
> +
> +#define TIMES4(a, b)
>   \
> +
>  (((b)&0xFFFFLL)<<48)+(((a)&0xFFFFLL)<<32)+(((b)&0xFFFFLL)<<16)+((a)&0xFFFFLL),
> \
> +
>  (((b)&0xFFFFLL)<<48)+(((a)&0xFFFFLL)<<32)+(((b)&0xFFFFLL)<<16)+((a)&0xFFFFLL)
> +
> +#if ARCH_X86_64
> +DECLARE_ALIGNED(16, const xmm_reg,  ff_w4_plus_w2) = { TIMES4(W4sh2,
> W2sh2) };
> +DECLARE_ALIGNED(16, const xmm_reg,  ff_w4_min_w2)  = { TIMES4(W4sh2,
> -W2sh2) };
> +DECLARE_ALIGNED(16, const xmm_reg,  ff_w4_plus_w6) = { TIMES4(W4sh2,
> +W6sh2) };
> +DECLARE_ALIGNED(16, const xmm_reg,  ff_w4_min_w6)  = { TIMES4(W4sh2,
> -W6sh2) };
> +DECLARE_ALIGNED(16, const xmm_reg,  ff_w1_plus_w3) = { TIMES4(W1sh2,
> +W3sh2) };
> +DECLARE_ALIGNED(16, const xmm_reg,  ff_w3_min_w1)  = { TIMES4(W3sh2,
> -W1sh2) };
> +DECLARE_ALIGNED(16, const xmm_reg,  ff_w7_plus_w3) = { TIMES4(W7sh2,
> +W3sh2) };
> +DECLARE_ALIGNED(16, const xmm_reg,  ff_w3_min_w7)  = { TIMES4(W3sh2,
> -W7sh2) };
> +DECLARE_ALIGNED(16, const xmm_reg,  ff_w1_plus_w5) = { TIMES4(W1sh2,
> +W5sh2) };
> +DECLARE_ALIGNED(16, const xmm_reg,  ff_w5_min_w1)  = { TIMES4(W5sh2,
> -W1sh2) };
> +DECLARE_ALIGNED(16, const xmm_reg,  ff_w5_plus_w7) = { TIMES4(W5sh2,
> +W7sh2) };
> +DECLARE_ALIGNED(16, const xmm_reg,  ff_w7_min_w5)  = { TIMES4(W7sh2,
> -W5sh2) };
> +#endif


No no no no no no no no no no no no no no no ^1000001.

Check out "const" in x86inc.asm.

%macro mymacro 2
const w4_plus_w2 times 4 dw %1, %2
%endmacro

mymacro(W4sh2, W2sh2)

etc.

And then use cextern in the files where you want to access this constant.

Ronald


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