[FFmpeg-devel] [PATCH 2/5] DCA: use a local variable for loop boundary
Mans Rullgard
mans
Mon Apr 12 00:05:51 CEST 2010
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);
}
--
1.7.0.4
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