"Ronald S. Bultje" <[email protected]> writes:

> Hi,
>
> 2011/9/10 Måns Rullgård <[email protected]>:
>> Luca Barbato <[email protected]> writes:
>>
>>> On 8/26/11 3:33 AM, Måns Rullgård wrote:
>>>> "Ronald S. Bultje"<[email protected]>  writes:
>>>>
>>>>> From: "Ronald S. Bultje"<[email protected]>
>>>>>
>>>>>  From 52.503s (~40fps) to 27.973sec (~80fps) decoding of 480p sintel
>>>>> trailer, i.e. a ~2x speedup overall, on a Nexus S.
>>>>
>>>> [...]
>>>>
>>>>> --- a/libavcodec/arm/asm.S
>>>>> +++ b/libavcodec/arm/asm.S
>>>>> @@ -97,6 +97,12 @@ T       add             \rn, \rn, \rm
>>>>>   T       ldr             \rt, [\rn]
>>>>>   .endm
>>>>>
>>>>> +.macro  ldr_dpren       rt,  rn,  rm:vararg
>>>>> +A       ldr             \rt, [\rn, -\rm]
>>>>> +T       sub             \rt, \rn, \rm
>>>>> +T       ldr             \rt, [\rt]
>>>>> +.endm
>>>>> +
>>>>>   .macro  ldr_post        rt,  rn,  rm:vararg
>>>>>   A       ldr             \rt, [\rn], \rm
>>>>>   T       ldr             \rt, [\rn]
>>>>> @@ -133,6 +139,12 @@ T       ldrh            \rt, [\rn]
>>>>>   T       add             \rn, \rn, \rm
>>>>>   .endm
>>>>>
>>>>> +.macro  ldrb_post       rt,  rn,  rm
>>>>> +A       ldrb            \rt, [\rn], \rm
>>>>> +T       ldrb            \rt, [\rn]
>>>>> +T       add             \rn, \rn, \rm
>>>>> +.endm
>>>>
>>>> Those macro names are very badly chosen.
>>>
>>> ldrb_post seems in line with ldr_post. ldr_dpren named as ldr_dpre
>>> seems equivalent to the other macros using sub. Which names you have
>>> in mind?
>>
>> I'm still trying to figure what "dpren" is supposed to denote.
>
> d is used for negative, pre is increment index before access. The dpre
> macro, however, still changes the argument, as if there were an
> exclamation mark (ldr r0, [r1, r2]!), whereas I want to use them
> without changing the pointer, so a "no change to pointer" is what the
> n stands for.
>
> d pre n = dpren. Other naming suggestions are welcome.

Names should indicate what things do, not what they do not do.

-- 
Måns Rullgård
[email protected]
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