static void filter(priv_t * p)
{
int i, num_in = max(0, fifo_occupancy(&p->input_fifo));
filter_t const * f = p->filter_ptr;
int const overlap = f->num_taps - 1;
double * output;
while (num_in >= f->dft_length) {
double const * input = fifo_read_ptr(&p->input_fifo);
fifo_read(&p->input_fifo, f->dft_length - overlap, NULL);
num_in -= f->dft_length - overlap;
output = fifo_reserve(&p->output_fifo, f->dft_length);
fifo_trim_by(&p->output_fifo, overlap);
memcpy(output, input, f->dft_length * sizeof(*output));
lsx_rdft(f->dft_length, 1, output, lsx_fft_br, lsx_fft_sc);
output[0] *= f->coefs[0];
output[1] *= f->coefs[1];
for (i = 2; i < f->dft_length; i += 2) {
double tmp = output[i];
output[i ] = f->coefs[i ] * tmp - f->coefs[i+1] * output[i+1];
output[i+1] = f->coefs[i+1] * tmp + f->coefs[i ] * output[i+1];
}
lsx_rdft(f->dft_length, -1, output, lsx_fft_br, lsx_fft_sc);
}
}
static void double_sample(stage_t * p, fifo_t * output_fifo)
{
sox_sample_t * output;
int i, j, num_in = max(0, fifo_occupancy(&p->fifo));
rate_shared_t const * s = p->shared;
dft_filter_t const * f = &s->half_band[p->which];
int const overlap = f->num_taps - 1;
#ifdef SSE_
const float * const coeff = f->coefs;
sox_sample_t tmp;
__m128 coef, outp, sign;
sign = SIGN;
#endif
while (p->rem + p->tuple * num_in >= f->dft_length) {
div_t divd = div(f->dft_length - overlap - p->rem + p->tuple - 1, p->tuple);
sox_sample_t const * input = fifo_read_ptr(&p->fifo);
fifo_read(&p->fifo, divd.quot, NULL);
num_in -= divd.quot;
output = fifo_reserve_aligned(output_fifo, f->dft_length);
fifo_trim_by(output_fifo, overlap);
memset(output, 0, f->dft_length * sizeof(*output));
for (j = 0, i = p->rem; i < f->dft_length; ++j, i += p->tuple)
output[i] = input[j];
p->rem = p->tuple - 1 - divd.rem;
ff_rdft_x(f->dft_length, 1, output, f->tmp_buf);
#ifdef SSE_
output[0] *= coeff[0];
output[1] *= coeff[1];
tmp = output[2];
output[2] = coeff[2] * tmp - coeff[3] * output[3];
output[3] = coeff[3] * tmp + coeff[2] * output[3];
for (i = 4; i < f->dft_length; i += 4)
{
outp = _mm_load_ps(output+i);
coef = _mm_load_ps(coeff+i);
_mm_store_ps(output+i, ZMUL2(outp, coef, sign));
}
#else
output[0] *= f->coefs[0];
output[1] *= f->coefs[1];
for (i = 2; i < f->dft_length; i += 2) {
sox_sample_t tmp = output[i];
output[i ] = f->coefs[i ] * tmp - f->coefs[i+1] * output[i+1];
output[i+1] = f->coefs[i+1] * tmp + f->coefs[i ] * output[i+1];
}
#endif
ff_rdft_x(f->dft_length, -1, output, f->tmp_buf);
}
}