[Mesa-dev] [PATCH] glsl: couple shader_enums cleanups

[Rob Clark]

On Fri, Oct 9, 2015 at 8:07 PM, Emil Velikov <emil.l.velikov at gmail.com> wrote:
> On 9 October 2015 at 23:27, Rob Clark <robdclark at gmail.com> wrote:
>> On Fri, Oct 9, 2015 at 5:57 PM, Emil Velikov <emil.l.velikov at gmail.com> wrote:
>>> On 9 October 2015 at 21:31, Rob Clark <robdclark at gmail.com> wrote:
>>>> From: Rob Clark <robclark at freedesktop.org>
>>>>
>>>> Add missing enum to gl_system_value_name() and move VARYING_SLOT_MAX /
>>>> FRAG_RESULT_MAX / etc into shader_enums.h as suggested by Emil.
>>>>
>>>> Reported-by: Emil Velikov <emil.l.velikov at gmail.com>
>>>> Signed-off-by: Rob Clark <robclark at freedesktop.org>
>>>> ---
>>>> Note: punted on the STATIC_ASSERT() thing for now..  kinda wanted some-
>>>> think more like tgsi_strings_check() where we check everything once on
>>>> startup, so you don't have to trigger something that calls the various
>>>> xyz_name() to realize something is out of sync.
>>>>
>>> I'm confused - isn't static_assert a compile thing ?
>>
>> oh, heh, good point..
>>
>>>>  src/glsl/nir/shader_enums.c | 1 +
>>>>  src/glsl/nir/shader_enums.h | 7 +++++++
>>>>  src/mesa/main/mtypes.h      | 5 -----
>>>>  3 files changed, 8 insertions(+), 5 deletions(-)
>>>>
>>>> diff --git a/src/glsl/nir/shader_enums.c b/src/glsl/nir/shader_enums.c
>>>> index 3722475..7fcbe81 100644
>>>> --- a/src/glsl/nir/shader_enums.c
>>>> +++ b/src/glsl/nir/shader_enums.c
>>>> @@ -169,6 +169,7 @@ const char * gl_system_value_name(gl_system_value sysval)
>>>>       ENUM(SYSTEM_VALUE_TESS_LEVEL_INNER),
>>>>       ENUM(SYSTEM_VALUE_LOCAL_INVOCATION_ID),
>>>>       ENUM(SYSTEM_VALUE_WORK_GROUP_ID),
>>>> +     ENUM(SYSTEM_VALUE_NUM_WORK_GROUPS),
>>>>       ENUM(SYSTEM_VALUE_VERTEX_CNT),
>>>>     };
>>>>     return NAME(sysval);
>>>> diff --git a/src/glsl/nir/shader_enums.h b/src/glsl/nir/shader_enums.h
>>>> index 2a5d2c5..77638ba 100644
>>>> --- a/src/glsl/nir/shader_enums.h
>>>> +++ b/src/glsl/nir/shader_enums.h
>>>> @@ -233,6 +233,11 @@ typedef enum
>>>>     VARYING_SLOT_VAR31,
>>>>  } gl_varying_slot;
>>>>
>>>> +
>>>> +#define VARYING_SLOT_MAX       (VARYING_SLOT_VAR0 + MAX_VARYING)
>>> I'd keep this and FRAG_RESULT_MAX defined as FOO + 1. Otherwise we'll
>>> end in funny spaghetti of header dependencies due to the extra two
>>> macros.
>>
>> not quite sure, but it sounds like you are asking to open-code
>> MAX_VARYINGS?  I don't think that is needed since that seems to
>> basically be a global config.h type thing (I mean mesa/main/config.h,
>> not autoconf one)
>>
>> There isn't really *supposed* to be a VARYING_SLOT_VAR(n-1) (ignoring
>> the fact that I added them simply to get nice string values to print
>> out in nir_print)
>>
> I was thinking that #define VARYING_SLOT_MAX (VARYING_SLOT_VAR + 1)
> /*VARYING_SLOT_VAR(n) */ is the preferred way.
> Hmm can you please point me in the right direction, as to why having
> VARYING_SLOT_VAR(n-1) is a bad idea ?

A few of the enums are meant to have their last element be interpreted
as xyz0 + n (where n < #define MAX_xyz from config.h)

I guess technically the max isn't something that is likely to change
frequently but if we ignore the MAX_xyz from config.h that means we
have two places to update if the max was ever increased.

>>>> +#define VARYING_SLOT_PATCH0    (VARYING_SLOT_MAX)
>>>> +#define VARYING_SLOT_TESS_MAX  (VARYING_SLOT_PATCH0 + MAX_VARYING)
>>>> +
>>> As there are defined 'on top'/'after' of the existing enum perhaps we
>>> should keep them alongside their PRIM_MAX...UNKNOWN brethren ?
>>
>> PRIM_MAX is a different thing, not related to anything that is already
>> in shader_enums..
>>
> I had in mind the relationship wrt the respective enums/macros, rather
> than their meaning. Although with the _MAX above in mind, I'm likely
> missing something.

prim == gl draw primitive (ie. tris/tristrip/quads/points/etc)..  not
something that is internal to mesa or in shader_enums.h..

BR,
-R

> Thanks
> Emil