[Mesa-dev] [PATCH] gallium/r600: Replace ALIGN_DIVUP with DIV_ROUND_UP

[Nicolai Hähnle]

On 30.12.2015 08:42, Krzysztof A. Sobiecki wrote:
> Nicolai Hähnle <nhaehnle at gmail.com> writes:
>
>> On 29.12.2015 14:27, Krzysztof A. Sobiecki wrote:
>>> From: Krzysztof Sobiecki <sobkas at gmail.com>
>>>
>>> ALIGN_DIVUP is a driver specific(r600g) macro that duplicates DIV_ROUND_UP functionality.
>>> Replacing it with DIV_ROUND_UP eliminates this problems.
>>
>> Those macros are actually slightly different, and the assembly
>> generated by the ALIGN_DIVUP looks clearly better to me.
>>
>> I remember seeing a very long thread about this not so long ago - what
>> was the resolution there?
>>
>> Cheers,
>> Nicolai
>>
> I would like to remove ALIGN_DIVUP first and then debate with
> implementation DIV_ROUND_UP should use.
>
> btw. I prefer 1 + ((x - 1) / y)

That produces an incorrect result when x is an unsigned type and equal 
to 0 -- and that is something that existing code definitely relies on.

Cheers,
Nicolai