void recursiveEval(const CubeSlice<zz_p>& s,
const Vec< copied_ptr<FFTHelper> >& multiEvalPoints,
long d,
zz_pX& tmp1,
Vec<zz_p>& tmp2)
{
long numDims = s.getNumDims();
//OLD: assert(numDims > 0);
helib::assertTrue(numDims > 0, "CubeSlice s has negative dimension number");
if (numDims > 1) {
long dim0 = s.getDim(0);
for (long i = 0; i < dim0; i++)
recursiveEval(CubeSlice<zz_p>(s, i), multiEvalPoints, d+1, tmp1, tmp2);
}
long posBnd = s.getProd(1);
for (long pos = 0; pos < posBnd; pos++) {
getHyperColumn(tmp1.rep, s, pos);
tmp1.normalize();
multiEvalPoints[d]->FFT(tmp1, tmp2);
setHyperColumn(tmp2, s, pos);
}
}
// Get multiple layers of a Benes permutation network. Returns in out[i][j]
// the shift amount to move item j in the i'th layer. Also isID[i]=true if
// the i'th layer is the identity (i.e., contains only 0 shift amounts).
void ColPerm::getBenesShiftAmounts(Vec<Permut>& out, Vec<bool>& isID,
const Vec<long>& benesLvls) const
{
// Go over the columns one by one. For each column extract the columns
// permutation, prepare a Benes network for it, and then for every layer
// compute the shift amounts for this columns.
long n = getDim(dim); // the permutations are over [0,n-1]
// Allocate space
out.SetLength(benesLvls.length());
isID.SetLength(benesLvls.length());
for (long k=0; k<benesLvls.length(); k++) {
out[k].SetLength(getSize());
isID[k] = true;
}
Vec<long> col;
col.SetLength(n);
for (long slice_index = 0; slice_index < numSlices(dim); slice_index++) {
ConstCubeSlice<long> slice(*this, slice_index, dim);
for (long col_index = 0; col_index < slice.numCols(); col_index++) {
getHyperColumn(col, slice, col_index);
GeneralBenesNetwork net(col); // build a Benes network for this column
// Sanity checks: width of network == n,
// and sum of benesLvls entries == # of levels
assert(net.getSize()==n);
{long sum=0;
for (long k=0; k<benesLvls.length(); k++) sum+=benesLvls[k];
assert(net.getNumLevels()==sum);
}
// Compute the layers of the collapased network for this column
for (long lvl=0,k=0; k<benesLvls.length(); lvl += benesLvls[k], k++) {
// Returns in col the shift amounts for this layer in the network,
// restricted to this column. Also returns true if the returned
// permutation is the idendity, false otherwise.
bool id = collapseBenesLevels(col, net, lvl, benesLvls[k]);
isID[k] = isID[k] && id;
CubeSlice<long> oslice(out[k], getSig());
CubeSlice<long> osubslice(oslice, slice_index, dim);
setHyperColumn(col, osubslice, col_index);
} // next collapsed layer
} // next column
} // next slice
}
void recursiveInterp(const CubeSlice<zz_p>& s,
const Vec< copied_ptr<FFTHelper> >& multiEvalPoints,
long d,
zz_pX& tmp1,
Vec<zz_p>& tmp2)
{
long numDims = s.getNumDims();
assert(numDims > 0);
long posBnd = s.getProd(1);
for (long pos = 0; pos < posBnd; pos++) {
getHyperColumn(tmp2, s, pos);
multiEvalPoints[d]->iFFT(tmp1, tmp2, false); // do not normalize
setHyperColumn(tmp1.rep, s, pos, zz_p::zero());
}
if (numDims > 1) {
long dim0 = s.getDim(0);
for (long i = 0; i < dim0; i++)
recursiveInterp(CubeSlice<zz_p>(s, i), multiEvalPoints, d+1, tmp1, tmp2);
}
}
// This routine recursively reduces each hypercolumn
// in dimension d (viewed as a coeff vector) by Phi_{m_d}(X)
// If one starts with a cube of dimension (m_1, ..., m_k),
// one ends up with a cube that is effectively of dimension
// phi(m_1, ..., m_k). Viewed as an element of the ring
// F_p[X_1,...,X_k]/(Phi_{m_1}(X_1), ..., Phi_{m_k}(X_k)),
// the cube remains unchanged.
static void recursiveReduce(const CubeSlice<zz_p>& s,
const Vec<zz_pXModulus>& cycVec,
long d,
zz_pX& tmp1,
zz_pX& tmp2)
{
long numDims = s.getNumDims();
//OLD: assert(numDims > 0);
helib::assertTrue(numDims > 0l, "CubeSlice s has negative number of dimensions");
long deg0 = deg(cycVec[d]);
long posBnd = s.getProd(1);
for (long pos = 0; pos < posBnd; pos++) {
getHyperColumn(tmp1.rep, s, pos);
tmp1.normalize();
// tmp2 may not be normalized, so clear it first
clear(tmp2);
rem(tmp2, tmp1, cycVec[d]);
// now pad tmp2.rep with zeros to length deg0...
// tmp2 may not be normalized
long len = tmp2.rep.length();
tmp2.rep.SetLength(deg0);
for (long i = len; i < deg0; i++) tmp2.rep[i] = 0;
setHyperColumn(tmp2.rep, s, pos);
}
if (numDims == 1) return;
for (long i = 0; i < deg0; i++)
recursiveReduce(CubeSlice<zz_p>(s, i), cycVec, d+1, tmp1, tmp2);
}
void recursiveEval(const CubeSlice<zz_p>& s,
const Vec< Vec<zz_p> >& multiEvalPoints,
long d,
zz_pX& tmp1,
Vec<zz_p>& tmp2)
{
long numDims = s.getNumDims();
assert(numDims > 0);
if (numDims > 1) {
long dim0 = s.getDim(0);
for (long i = 0; i < dim0; i++)
recursiveEval(CubeSlice<zz_p>(s, i), multiEvalPoints, d+1, tmp1, tmp2);
}
long posBnd = s.getProd(1);
for (long pos = 0; pos < posBnd; pos++) {
getHyperColumn(tmp1.rep, s, pos);
tmp1.normalize();
eval(tmp2, tmp1, multiEvalPoints[d]);
setHyperColumn(tmp2, s, pos);
}
}
