int PFC::precomp_for_mult(G2& w,BOOL small)
{
ECn3 v;
ZZn3 x,y;
int i,j,k,bp,is,t;
if (small) t=MR_ROUNDUP(2*S,WINDOW_SIZE);
else t=MR_ROUNDUP(bits(*ord),WINDOW_SIZE);
w.g.norm();
v=w.g;
w.mtable=new ECn3[1<<WINDOW_SIZE];
v.norm();
w.mtable[1]=v;
w.mtbits=t;
for (j=0;j<t;j++)
v+=v;
k=1;
for (i=2;i<(1<<WINDOW_SIZE);i++)
{
if (i==(1<<k))
{
k++;
v.norm();
w.mtable[i]=v;
for (j=0;j<t;j++)
v+=v;
continue;
}
bp=1;
for (j=0;j<k;j++)
{
if (i&bp)
{
is=1<<j;
w.mtable[i]+=w.mtable[is];
}
bp<<=1;
}
w.mtable[i].norm();
}
return (1<<WINDOW_SIZE);
}
BOOL ate(ECn3& Q,ECn& P,Big &x,ZZn2& X,ZZn6& res)
{
int i,j,n,nb,nbw,nzs;
ECn3 A;
ZZn Px,Py;
ZZn6 w;
Big q=x*x-x+1;
#ifdef MR_COUNT_OPS
fpc=fpa=fpx=0;
#endif
normalise(P);
#ifdef PROJECTIVE
Q.norm();
#endif
extract(P,Px,Py);
Px+=Px; // because x^6+2 is irreducible.. simplifies line function calculation
Py+=Py;
res=1;
A=Q; // reset A
nb=bits(x);
res.mark_as_miller();
for (i=nb-2;i>=0;i--)
{
res*=res;
res*=g(A,A,Px,Py);
if (bit(x,i)==1)
res*=g(A,Q,Px,Py);
if (res.iszero()) return FALSE;
}
#ifdef MR_COUNT_OPS
printf("After Miller fpc= %d fpa= %d fpx= %d\n",fpc,fpa,fpx);
#endif
// if (!A.iszero() || res.iszero()) return FALSE;
w=res;
w.powq(X);
res*=w; // ^(p+1)
w=res;
w.powq(X); w.powq(X); w.powq(X);
res=w/res; // ^(p^3-1)
// exploit the clever "trick" for a half-length exponentiation!
res.mark_as_unitary();
w=res;
res.powq(X); // res*=res; // res=pow(res,CF);
if (x<0) res/=powu(w,-x);
else res*=powu(w,x);
#ifdef MR_COUNT_OPS
printf("After pairing fpc= %d fpa= %d fpx= %d\n",fpc,fpa,fpx);
fpa=fpc=fpx=0;
#endif
if (res==(ZZn6)1) return FALSE;
return TRUE;
}
