Texas Instruments TMS320C64X Programmer's Reference Manual page 127

#include <stdio.h>
#include <stdlib.h>
#if 0
# define DIG_REV(i, m, j) ((j) = (_shfl(_rotl(_bitr(_deal(i)), 16)) >> (m)))
#else
# define DIG_REV(i, m, j)
do {
unsigned _ = (i);
_ = ((_ & 0x33333333) <<
_ = ((_ & 0x0F0F0F0F) <<
_ = ((_ & 0x00FF00FF) <<
_ = ((_ & 0x0000FFFF) << 16) | ((_ & ~0x0000FFFF) >> 16);
(j) = _ >> (m);
} while (0)
#endif
void fft_cn
(
const short *restrict w,
int n,
short *restrict x,
short *restrict y
)
{
int stride, i, j, k, t, s, m;
short xh0, xh1,
short xl0, xl1,
short xt0, yt0,
short xt2, yt2,
/*−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−*/
/* Inform the compiler that the
/* "w" and output array "y" are double word aligned.
/* number of points to be transformed is assumed to be greater than or
/* equal to 16, and less than 32768.
/*−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−*/
#ifndef NOASSUME
2) | ((_ & ~0x33333333) >>
4) | ((_ & ~0x0F0F0F0F) >>
8) | ((_ & ~0x00FF00FF) >>
xh20, xh21;
xl20, xl21;
xt1, yt1;
xt3, yt3;
input array "x", twiddle factor array
2);
4);
8);
In addition, the
C64x+ DSPLIB Reference
DSP_fft
\
\
\
\
\
\
\
\
*/
*/
*/
*/
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