[Mesa-dev] [PATCH 1/6] gallium: add some more double opcodes to avoid unnecessary lowering

[Roland Scheidegger]

Just some minor nits.

Am 20.02.2015 um 00:52 schrieb Ilia Mirkin:
> Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu>
> ---
>  src/gallium/auxiliary/tgsi/tgsi_info.c     |  5 ++++
>  src/gallium/docs/source/tgsi.rst           | 39 ++++++++++++++++++++++++++++++
>  src/gallium/include/pipe/p_shader_tokens.h |  7 +++++-
>  3 files changed, 50 insertions(+), 1 deletion(-)
> 
> diff --git a/src/gallium/auxiliary/tgsi/tgsi_info.c b/src/gallium/auxiliary/tgsi/tgsi_info.c
> index d04f9da..4d838fd 100644
> --- a/src/gallium/auxiliary/tgsi/tgsi_info.c
> +++ b/src/gallium/auxiliary/tgsi/tgsi_info.c
> @@ -257,6 +257,11 @@ static const struct tgsi_opcode_info opcode_info[TGSI_OPCODE_LAST] =
>     { 1, 1, 0, 0, 0, 0, COMP, "D2U", TGSI_OPCODE_D2U },
>     { 1, 1, 0, 0, 0, 0, COMP, "U2D", TGSI_OPCODE_U2D },
>     { 1, 1, 0, 0 ,0, 0, COMP, "DRSQ", TGSI_OPCODE_DRSQ },
> +   { 1, 1, 0, 0, 0, 0, COMP, "DTRUNC", TGSI_OPCODE_DTRUNC },
> +   { 1, 1, 0, 0, 0, 0, COMP, "DCEIL", TGSI_OPCODE_DCEIL },
> +   { 1, 1, 0, 0, 0, 0, COMP, "DFLR", TGSI_OPCODE_DFLR },
> +   { 1, 1, 0, 0, 0, 0, COMP, "DROUND", TGSI_OPCODE_DROUND },
> +   { 1, 1, 0, 0, 0, 0, COMP, "DSSG", TGSI_OPCODE_DSSG },
>  };
>  
>  const struct tgsi_opcode_info *
> diff --git a/src/gallium/docs/source/tgsi.rst b/src/gallium/docs/source/tgsi.rst
> index e20af79..15f1e9f 100644
> --- a/src/gallium/docs/source/tgsi.rst
> +++ b/src/gallium/docs/source/tgsi.rst
> @@ -1861,6 +1861,45 @@ two-component vectors with doubled precision in each component.
>  
>    dst.zw = src.zw - \lfloor src.zw\rfloor
>  
> +.. opcode:: DTRUNC - Truncate
> +
> +.. math::
> +
> +  dst.xy = trunc(src.xy)
> +
> +  dst.zw = trunc(src.zw)
> +
> +.. opcode:: DCEIL - Ceiling
> +
> +.. math::
> +
> +  dst.xy = \lceil src.xy\rceil
> +
> +  dst.zw = \lceil src.zw\rceil
> +
> +.. opcode:: DFLR - Floor
> +
> +.. math::
> +
> +  dst.xy = \lfloor src.xy\rfloor
> +
> +  dst.zw = \lfloor src.zw\rfloor
> +
> +.. opcode:: DROUND - Fraction
> +
> +.. math::
> +
> +  dst.xy = round(src.xy)
> +
> +  dst.zw = round(src.zw)
> +
> +.. opcode:: DSSG - Set Sign
> +
> +.. math::
> +
> +  dst.xy = (src.xy > 0) ? 1 : (src.xy < 0) ? -1 : 0
> +
> +  dst.zw = (src.zw > 0) ? 1 : (src.zw < 0) ? -1 : 0
I think this would be more obvious written as 1.0/-1.0/0.0 (same goes
for the non-double version, of course).
(As a side note, I'm wondering if this actually has defined NaN
behavior, the glsl language sort of implies a number has to be exactly
one of these 3 cases, and doesn't give an answer what should be returned
for a NaN - maybe a NaN?)

>  
>  .. opcode:: DFRACEXP - Convert Number to Fractional and Integral Components
>  
> diff --git a/src/gallium/include/pipe/p_shader_tokens.h b/src/gallium/include/pipe/p_shader_tokens.h
> index fc41cc9..95ac590 100644
> --- a/src/gallium/include/pipe/p_shader_tokens.h
> +++ b/src/gallium/include/pipe/p_shader_tokens.h
> @@ -519,7 +519,12 @@ struct tgsi_property_data {
>  #define TGSI_OPCODE_D2U                 215
>  #define TGSI_OPCODE_U2D                 216
>  #define TGSI_OPCODE_DRSQ                217 /* eg, cayman also has DRSQ */
> -#define TGSI_OPCODE_LAST                218
> +#define TGSI_OPCODE_DTRUNC              218 /* nvc0 */
> +#define TGSI_OPCODE_DCEIL               219 /* nvc0 */
> +#define TGSI_OPCODE_DFLR                220 /* nvc0 */
> +#define TGSI_OPCODE_DROUND              221 /* nvc0 */
> +#define TGSI_OPCODE_DSSG                222
> +#define TGSI_OPCODE_LAST                223

I don't think these hw-specific references (nvc0) really fit in there -
the same can be said about some existing ones (cayman...)

>  #define TGSI_SAT_NONE            0  /* do not saturate */
>  #define TGSI_SAT_ZERO_ONE        1  /* clamp to [0,1] */
> 

Otherwise looks good to me.

Roland