shithub: opus

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better mdct_backward() indexing

--- a/libcelt/mdct.c

+++ b/libcelt/mdct.c

@@ -194,6 +194,8 @@

    /* Post-rotate */

    {

       kiss_fft_scalar * restrict fp = f;

+      kiss_fft_scalar *t = &l->trig[0];

+

       for(i=0;i<N4;i++)

       {

          kiss_fft_scalar re, im;

@@ -200,9 +202,9 @@

          re = fp[0];

          im = fp[1];

          /* We'd scale up by 2 here, but instead it's done when mixing the windows */

-         fp[0] = S_MUL(re,l->trig[i]) + S_MUL(im,l->trig[i+N4]);

-         fp[1] = S_MUL(im,l->trig[i]) - S_MUL(re,l->trig[i+N4]);

-         fp += 2;

+         *fp++ = S_MUL(re,*t) + S_MUL(im,t[N4]);

+         *fp++ = S_MUL(im,*t) - S_MUL(re,t[N4]);

+         t++;

       }

    }

    /* De-shuffle the components for the middle of the window only */