ThinEvalMap::ThinEvalMap(const EncryptedArray& _ea,
bool minimal,
const Vec<long>& mvec,
bool _invert,
bool build_cache)
: ea(_ea), invert(_invert)
{
const FHEcontext& context = ea.getContext();
const PAlgebra& zMStar = ea.getPAlgebra();
long p = zMStar.getP();
long d = zMStar.getOrdP();
// FIXME: we should check that ea was initilized with
// G == factors[0], but this is a slight pain to check
// currently
// NOTE: this code is derived from a more general setting, and
// could certainly be greatly simplified
nfactors = mvec.length();
//OLD: assert(nfactors > 0);
helib::assertTrue(nfactors > 0, "Invalid argument: mvec must have positive length");
for (long i = 0; i < nfactors; i++) {
for (long j = i+1; j < nfactors; j++) {
helib::assertEq(GCD(mvec[i], mvec[j]), 1l, "Invalid argument: mvec must have pairwise-disjoint entries");
}
}
long m = computeProd(mvec);
//OLD: assert(m == long(zMStar.getM()));
helib::assertEq(m, (long)zMStar.getM(), "Invalid argument: mvec's product does not match ea's m");
Vec<long> phivec(INIT_SIZE, nfactors);
for (long i = 0; i < nfactors; i++) phivec[i] = phi_N(mvec[i]);
long phim = computeProd(phivec);
Vec<long> dprodvec(INIT_SIZE, nfactors+1);
dprodvec[nfactors] = 1;
for (long i = nfactors-1; i >= 0; i--)
dprodvec[i] = dprodvec[i+1] *
multOrd(PowerMod(p % mvec[i], dprodvec[i+1], mvec[i]), mvec[i]);
Vec<long> dvec(INIT_SIZE, nfactors);
for (long i = 0; i < nfactors; i++)
dvec[i] = dprodvec[i] / dprodvec[i+1];
long nslots = phim/d;
//OLD: assert(d == dprodvec[0]);
helib::assertEq(d, dprodvec[0], "d must match the first entry of dprodvec");
//OLD: assert(nslots == long(zMStar.getNSlots()));
helib::assertEq(nslots, (long)zMStar.getNSlots(), "Invalid argument: mismatch of number of slots");
long inertPrefix = 0;
for (long i = 0; i < nfactors && dvec[i] == 1; i++) {
inertPrefix++;
}
if (inertPrefix != nfactors-1)
throw helib::LogicError("ThinEvalMap: case not handled: bad inertPrefix");
Vec< Vec<long> > local_reps(INIT_SIZE, nfactors);
for (long i = 0; i < nfactors; i++)
init_representatives(local_reps[i], i, mvec, zMStar);
Vec<long> crtvec(INIT_SIZE, nfactors);
for (long i = 0; i < nfactors; i++)
crtvec[i] = (m/mvec[i]) * InvMod((m/mvec[i]) % mvec[i], mvec[i]);
Vec<long> redphivec(INIT_SIZE, nfactors);
for (long i = 0; i < nfactors; i++)
redphivec[i] = phivec[i]/dvec[i];
CubeSignature redphisig(redphivec);
Vec< shared_ptr<CubeSignature> > sig_sequence;
sig_sequence.SetLength(nfactors+1);
sig_sequence[nfactors] = shared_ptr<CubeSignature>(new CubeSignature(phivec));
Vec<long> reduced_phivec = phivec;
for (long dim = nfactors-1; dim >= 0; dim--) {
reduced_phivec[dim] /= dvec[dim];
sig_sequence[dim] =
shared_ptr<CubeSignature>(new CubeSignature(reduced_phivec));
}
matvec.SetLength(nfactors);
if (invert) {
long dim = nfactors - 1;
unique_ptr<MatMul1D> mat1_data;
mat1_data.reset(buildThinStep1Matrix(ea, sig_sequence[dim],
local_reps[dim], dim, m/mvec[dim]));
matvec[dim].reset(new MatMul1DExec(*mat1_data, minimal));
}
else {
long dim = nfactors - 1;
unique_ptr<MatMul1D> mat1_data;
mat1_data.reset(buildThinStep2Matrix(ea, sig_sequence[dim],
local_reps[dim], dim, m/mvec[dim], invert, /*inflate=*/true));
matvec[dim].reset(new MatMul1DExec(*mat1_data, minimal));
}
for (long dim=nfactors-2; dim>=0; --dim) {
unique_ptr<MatMul1D> mat_data;
mat_data.reset(buildThinStep2Matrix(ea, sig_sequence[dim], local_reps[dim],
dim, m/mvec[dim], invert));
matvec[dim].reset(new MatMul1DExec(*mat_data, minimal));
}
if (build_cache) upgrade();
}
EvalMap::EvalMap(const EncryptedArray& _ea, const Vec<long>& mvec, bool _invert,
bool normal_basis)
: ea(_ea), invert(_invert)
{
const FHEcontext& context = ea.getContext();
const PAlgebra& zMStar = context.zMStar;
long p = zMStar.getP();
long d = zMStar.getOrdP();
// FIXME: we should check that ea was initilized with
// G == factors[0], but this is a slight pain to check
// currently
// NOTE: this code is derived from a more general setting, and
// could certainly be greatly simplified
nfactors = mvec.length();
assert(nfactors > 0);
for (long i = 0; i < nfactors; i++)
for (long j = i+1; j < nfactors; j++)
assert(GCD(mvec[i], mvec[j]) == 1);
long m = computeProd(mvec);
assert(m == long(zMStar.getM()));
Vec<long> phivec(INIT_SIZE, nfactors);
for (long i = 0; i < nfactors; i++) phivec[i] = phi_N(mvec[i]);
long phim = computeProd(phivec);
Vec<long> dprodvec(INIT_SIZE, nfactors+1);
dprodvec[nfactors] = 1;
for (long i = nfactors-1; i >= 0; i--)
dprodvec[i] = dprodvec[i+1] *
multOrd(PowerMod(p % mvec[i], dprodvec[i+1], mvec[i]), mvec[i]);
Vec<long> dvec(INIT_SIZE, nfactors);
for (long i = 0; i < nfactors; i++)
dvec[i] = dprodvec[i] / dprodvec[i+1];
long nslots = phim/d;
assert(d == dprodvec[0]);
assert(nslots == long(zMStar.getNSlots()));
long inertPrefix = 0;
for (long i = 0; i < nfactors && dvec[i] == 1; i++) {
inertPrefix++;
}
if (inertPrefix != nfactors-1)
Error("EvalMap: case not handled: bad inertPrefix");
Vec< Vec<long> > local_reps(INIT_SIZE, nfactors);
for (long i = 0; i < nfactors; i++)
init_representatives(local_reps[i], i, mvec, zMStar);
Vec<long> crtvec(INIT_SIZE, nfactors);
for (long i = 0; i < nfactors; i++)
crtvec[i] = (m/mvec[i]) * InvMod((m/mvec[i]) % mvec[i], mvec[i]);
Vec<long> redphivec(INIT_SIZE, nfactors);
for (long i = 0; i < nfactors; i++)
redphivec[i] = phivec[i]/dvec[i];
CubeSignature redphisig(redphivec);
Vec< shared_ptr<CubeSignature> > sig_sequence;
sig_sequence.SetLength(nfactors+1);
sig_sequence[nfactors] = shared_ptr<CubeSignature>(new CubeSignature(phivec));
Vec<long> reduced_phivec = phivec;
for (long dim = nfactors-1; dim >= 0; dim--) {
reduced_phivec[dim] /= dvec[dim];
sig_sequence[dim] =
shared_ptr<CubeSignature>(new CubeSignature(reduced_phivec));
}
long dim = nfactors - 1;
mat1.reset(buildStep1Matrix(ea, sig_sequence[dim],
local_reps[dim], dim, m/mvec[dim], invert, normal_basis));
matvec.SetLength(nfactors-1);
for (dim=nfactors-2; dim>=0; --dim) {
matvec[dim].reset(buildStep2Matrix(ea, sig_sequence[dim], local_reps[dim],
dim, m/mvec[dim], invert));
}
}
