Rearrange scaletempo inner loop.

Speedup on x86 with gcc 3.4 36%, on x86_64 with gcc 4.1 5%


git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@25100 b3059339-0415-0410-9bf9-f77b7e298cf2

1 files changed, 5 insertions, 2 deletions

diff --git a/libaf/af_scaletempo.c b/libaf/af_scaletempo.c
index b2de4c33ef..d4c3fe731e 100644
--- a/libaf/af_scaletempo.c
+++ b/libaf/af_scaletempo.c
@@ -170,9 +170,12 @@ static int best_overlap_offset_s16(af_scaletempo_t* s)
     int32_t corr = 0;
     int16_t* ps = search_start;
     ppc = s->buf_pre_corr;
-    for (i=s->num_channels; i<s->samples_overlap; i++) {
+    ppc += s->samples_overlap - s->num_channels;
+    ps  += s->samples_overlap - s->num_channels;
+    i  = -(s->samples_overlap - s->num_channels);
+    do {
       corr += ( *ppc++ * *ps++ ) >> s->shift_corr;
-    }
+    } while (++i < 0);
     if (corr > best_corr) {
       best_corr = corr;
       best_off  = off;