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modified time benchmark to repeat same buffer over and over to avoid IO bottlenecks and get more consistent numbers.

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This commit is contained in:
Mark Borgerding
2003-11-01 04:44:50 +00:00
parent 471803ca08
commit 8ac63adc77
5 changed files with 118 additions and 16 deletions
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39
kiss_fft.c
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@ -206,6 +206,43 @@ void bfly3(
}while(--m);
}
void bfly5(
kiss_fft_cpx * Fout,
int fstride,
const kiss_fft_state * st,
int m
)
{
int u,k,q1,q;
const int p=5;
kiss_fft_cpx * scratch = st->scratch;
kiss_fft_cpx * twiddles = st->twiddles;
kiss_fft_cpx t;
int Norig = st->nfft;
for ( u=0; u<m; ++u ) {
k=u;
for ( q1=0 ; q1<p ; ++q1 ) {
scratch[q1] = Fout[ k ];
C_FIXDIV(scratch[q1],p);
k += m;
}
k=u;
for ( q1=0 ; q1<p ; ++q1 ) {
int twidx=0;
Fout[ k ] = scratch[0];
for (q=1;q<p;++q ) {
twidx += fstride * k;
if (twidx>=Norig) twidx-=Norig;
C_MUL(t,scratch[q] , twiddles[twidx] );
C_ADDTO( Fout[ k ] ,t);
}
k += m;
}
}
}
/* perform the butterfly for one stage of a mixed radix FFT */
void bfly_generic(
kiss_fft_cpx * Fout,
@ -268,6 +305,7 @@ void fft_work(
case 2: bfly2(Fout,fstride,st,m); break;
case 3: bfly3(Fout,fstride,st,m); break;
case 4: bfly4(Fout,fstride,st,m); break;
case 5: bfly5(Fout,fstride,st,m); break;
default: bfly_generic(Fout,fstride,st,m,p); break;
}
}
@ -304,7 +342,6 @@ void * kiss_fft_alloc(int nfft,int inverse_fft)
st->scratch = (kiss_fft_cpx*)(st->tmpbuf + nfft);
st->factors = (int*)(st->scratch + nfft); /* just after tmpbuf*/
for (i=0;i<nfft;++i) {
const double pi=3.14159265358979323846264338327;
double phase = ( 2*pi /nfft ) * i;