[FFmpeg-devel] [PATCH 2/5] DCA: use a local variable for loop boundary

Måns Rullgård mans
Mon Apr 12 13:15:45 CEST 2010


Kostya <kostya.shishkov at gmail.com> writes:

> On Sun, Apr 11, 2010 at 11:05:51PM +0100, Mans Rullgard wrote:
>> This prevents gcc reloading the value from memory on each iteration
>> of the loop.
>> ---
>>  libavcodec/dca.c |    3 ++-
>>  1 files changed, 2 insertions(+), 1 deletions(-)
>> 
>> diff --git a/libavcodec/dca.c b/libavcodec/dca.c
>> index 596756c..7a6841d 100644
>> --- a/libavcodec/dca.c
>> +++ b/libavcodec/dca.c
>> @@ -757,6 +757,7 @@ static void qmf_32_subbands(DCAContext * s, int chans,
>>      const float *prCoeff;
>>      int i;
>>  
>> +    int sb_act = s->subband_activity[chans];
>>      int subindex;
>>  
>>      scale *= sqrt(1/8.0);
>> @@ -770,7 +771,7 @@ static void qmf_32_subbands(DCAContext * s, int chans,
>>      /* Reconstructed channel sample index */
>>      for (subindex = 0; subindex < 8; subindex++) {
>>          /* Load in one sample from each subband and clear inactive subbands */
>> -        for (i = 0; i < s->subband_activity[chans]; i++){
>> +        for (i = 0; i < sb_act; i++){
>>              uint32_t v = AV_RN32A(&samples_in[i][subindex]) ^ ((i-1)&2)<<30;
>>              AV_WN32A(&s->raXin[i], v);
>>          }
>
> looks ok

Applied.

-- 
M?ns Rullg?rd
mans at mansr.com



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