NE10_INLINE void ne10_mixed_radix_r2c_butterfly_float32_c (
ne10_fft_cpx_float32_t * Fout,
const ne10_fft_cpx_float32_t * Fin,
const ne10_int32_t * factors,
const ne10_fft_cpx_float32_t * twiddles,
ne10_fft_cpx_float32_t * buffer)
{
// PRINT_POINTERS_INFO(Fin,Fout,buffer,twiddles);
ne10_int32_t fstride, mstride, nfft;
ne10_int32_t radix;
ne10_int32_t stage_count;
// init fstride, mstride, radix, nfft
stage_count = factors[0];
fstride = factors[1];
mstride = factors[ (stage_count << 1) - 1 ];
radix = factors[ stage_count << 1 ];
nfft = radix * fstride;
// PRINT_STAGE_INFO;
if (stage_count % 2 == 0)
{
ne10_swap_ptr (buffer, Fout);
}
// the first stage
if (radix == 8) // length of FFT is 2^n (n is odd)
{
// PRINT_POINTERS_INFO(Fin,Fout,buffer,twiddles);
ne10_radix8_r2c_c (Fout, Fin, fstride, mstride, nfft);
}
else if (radix == 4) // length of FFT is 2^n (n is even)
{
// PRINT_POINTERS_INFO(Fin,Fout,buffer,twiddles);
ne10_radix4_r2c_c (Fout, Fin, fstride, mstride, nfft);
}
// end of first stage
// others
for (; fstride > 1;)
{
fstride >>= 2;
ne10_swap_ptr (buffer, Fout);
// PRINT_POINTERS_INFO(Fin,Fout,buffer,twiddles);
ne10_radix4_r2c_with_twiddles_c (Fout, buffer, fstride, mstride, nfft, twiddles);
twiddles += 3 * mstride;
mstride <<= 2;
} // other stage
}
NE10_INLINE void ne10_mixed_radix_c2r_butterfly_float32_c (
ne10_fft_cpx_float32_t * Fout,
const ne10_fft_cpx_float32_t * Fin,
const ne10_int32_t * factors,
const ne10_fft_cpx_float32_t * twiddles,
ne10_fft_cpx_float32_t * buffer)
{
// PRINT_POINTERS_INFO(Fin,Fout,buffer,twiddles);
ne10_int32_t fstride, mstride, nfft;
ne10_int32_t radix;
ne10_int32_t stage_count;
// init fstride, mstride, radix, nfft
stage_count = factors[0];
fstride = factors[1];
mstride = factors[ (stage_count << 1) - 1 ];
radix = factors[ stage_count << 1 ];
nfft = radix * fstride;
// fstride, mstride for the last stage
fstride = 1;
mstride = nfft >> 2;
// PRINT_STAGE_INFO;
if (stage_count % 2 == 1)
{
ne10_swap_ptr (buffer, Fout);
}
// last butterfly -- inversed
if (stage_count > 1)
{
twiddles -= 3 * mstride;
// PRINT_STAGE_INFO;
// PRINT_POINTERS_INFO(Fin,Fout,buffer,twiddles);
ne10_radix4_c2r_with_twiddles_c (buffer, Fin, fstride, mstride, nfft, twiddles);
fstride <<= 2;
mstride >>= 2;
stage_count --;
}
static inline void ne10_mixed_radix_generic_butterfly_float32_impl_c (ne10_fft_cpx_float32_t *Fout,
const ne10_fft_cpx_float32_t *Fin,
const ne10_int32_t *factors,
const ne10_fft_cpx_float32_t *twiddles,
ne10_fft_cpx_float32_t *buffer,
const ne10_int32_t is_inverse,
const ne10_int32_t is_scaled)
{
ne10_int32_t fstride, mstride, radix;
ne10_int32_t stage_count;
ne10_int32_t nfft;
// init fstride, mstride, radix, nfft
stage_count = factors[0];
fstride = factors[1];
mstride = 1;
radix = factors[stage_count << 1]; // radix of first stage
nfft = fstride * radix;
if (stage_count % 2 == 0)
{
ne10_swap_ptr (buffer, Fout);
}
// first stage
switch (radix)
{
case 2:
ne10_radix_2_butterfly_float32_c (Fout, Fin, NULL, fstride, 1, nfft, 1,
is_inverse, is_scaled);
break;
case 4:
ne10_radix_4_butterfly_float32_c (Fout, Fin, NULL, fstride, 1, nfft, 1,
is_inverse, is_scaled);
break;
case 3:
ne10_radix_3_butterfly_float32_c (Fout, Fin, NULL, fstride, 1, nfft, 1,
is_inverse, is_scaled);
break;
case 5:
ne10_radix_5_butterfly_float32_c (Fout, Fin, NULL, fstride, 1, nfft, 1,
is_inverse, is_scaled);
break;
case 8:
ne10_radix_8_butterfly_float32_c (Fout, Fin, NULL, fstride, 1, nfft, 1,
is_inverse, is_scaled);
default:
ne10_radix_generic_butterfly_float32_c (Fout, Fin, twiddles, radix,
fstride, 1, is_inverse, is_scaled);
break;
}
stage_count--;
if (!stage_count) // finish
{
return;
}
if (radix % 2)
{
twiddles += radix;
}
// other stges
while (stage_count > 0)
{
ne10_swap_ptr (buffer, Fout);
mstride *= radix;
// update radix
radix = factors[stage_count << 1];
assert ((radix > 1) && (radix < 6));
fstride /= radix;
switch (radix)
{
case 2:
ne10_radix_2_butterfly_float32_c (Fout, buffer, twiddles, fstride,
mstride, nfft, 0, is_inverse,
0); // Only scaling in the first stage.
break;
case 3:
ne10_radix_3_butterfly_float32_c (Fout, buffer, twiddles, fstride,
mstride, nfft, 0, is_inverse,
0); // Only scaling in the first stage.
break;
case 4:
ne10_radix_4_butterfly_float32_c (Fout, buffer, twiddles, fstride,
mstride, nfft, 0, is_inverse,
0); // Only scaling in the first stage.
break;
case 5:
ne10_radix_5_butterfly_float32_c (Fout, buffer, twiddles, fstride,
mstride, nfft, 0, is_inverse,
0); // Only scaling in the first stage.
break;
} // switch (radix)
twiddles += mstride * (radix - 1);
stage_count--;
} // while (stage_count)
}
