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Added SAT support for $div and $mod cells

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This commit is contained in:
Clifford Wolf 2013-08-11 16:27:15 +02:00
parent a5836af172
commit ccf36cb7d8
3 changed files with 55 additions and 0 deletions
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46
kernel/satgen.h
View file

@ -267,6 +267,52 @@ struct SatGen
return true;
}
if (cell->type == "$div" || cell->type == "$mod")
{
std::vector<int> a = importSigSpec(cell->connections.at("\\A"), timestep);
std::vector<int> b = importSigSpec(cell->connections.at("\\B"), timestep);
std::vector<int> y = importSigSpec(cell->connections.at("\\Y"), timestep);
extendSignalWidth(a, b, y, cell);
std::vector<int> a_u, b_u;
if (cell->parameters["\\A_SIGNED"].as_bool() && cell->parameters["\\B_SIGNED"].as_bool()) {
a_u = ez->vec_ite(a.back(), ez->vec_neg(a), a);
b_u = ez->vec_ite(b.back(), ez->vec_neg(b), b);
} else {
a_u = a;
b_u = b;
}
std::vector<int> chain_buf = a_u;
std::vector<int> y_u(a_u.size(), ez->FALSE);
for (int i = int(a.size())-1; i >= 0; i--)
{
chain_buf.insert(chain_buf.end(), chain_buf.size(), ez->FALSE);
std::vector<int> b_shl(i, ez->FALSE);
b_shl.insert(b_shl.end(), b_u.begin(), b_u.end());
b_shl.insert(b_shl.end(), chain_buf.size()-b_shl.size(), ez->FALSE);
y_u.at(i) = ez->vec_ge_unsigned(chain_buf, b_shl);
chain_buf = ez->vec_ite(y_u.at(i), ez->vec_sub(chain_buf, b_shl), chain_buf);
chain_buf.erase(chain_buf.begin() + a_u.size(), chain_buf.end());
}
if (cell->type == "$div") {
if (cell->parameters["\\A_SIGNED"].as_bool() && cell->parameters["\\B_SIGNED"].as_bool())
ez->assume(ez->vec_eq(y, ez->vec_ite(ez->XOR(a.back(), b.back()), ez->vec_neg(y_u), y_u)));
else
ez->assume(ez->vec_eq(y, y_u));
} else {
if (cell->parameters["\\A_SIGNED"].as_bool() && cell->parameters["\\B_SIGNED"].as_bool())
ez->assume(ez->vec_eq(y, ez->vec_ite(a.back(), ez->vec_neg(chain_buf), chain_buf)));
else
ez->assume(ez->vec_eq(y, chain_buf));
}
return true;
}
if (timestep > 0 && (cell->type == "$dff" || cell->type == "$_DFF_N_" || cell->type == "$_DFF_P_")) {
if (timestep == 1) {
initial_state.add((*sigmap)(cell->connections.at("\\Q")));

6
libs/ezsat/ezsat.cc
View file

@ -852,6 +852,12 @@ std::vector<int> ezSAT::vec_sub(const std::vector<int> &vec1, const std::vector<
return vec;
}
std::vector<int> ezSAT::vec_neg(const std::vector<int> &vec)
{
std::vector<int> zero(vec.size(), FALSE);
return vec_sub(zero, vec);
}
void ezSAT::vec_cmp(const std::vector<int> &vec1, const std::vector<int> &vec2, int &carry, int &overflow, int &sign, int &zero)
{
assert(vec1.size() == vec2.size());

3
libs/ezsat/ezsat.h
View file

@ -223,6 +223,7 @@ public:
std::vector<int> vec_count(const std::vector<int> &vec, int bits, bool clip = true);
std::vector<int> vec_add(const std::vector<int> &vec1, const std::vector<int> &vec2);
std::vector<int> vec_sub(const std::vector<int> &vec1, const std::vector<int> &vec2);
std::vector<int> vec_neg(const std::vector<int> &vec);
void vec_cmp(const std::vector<int> &vec1, const std::vector<int> &vec2, int &carry, int &overflow, int &sign, int &zero);
@ -305,6 +306,8 @@ struct ezSATvec
ezSATvec(ezSAT &sat, const std::vector<int> &vec) : sat(sat), vec(vec) { }
ezSATvec operator ~() { return ezSATvec(sat, sat.vec_not(vec)); }
ezSATvec operator -() { return ezSATvec(sat, sat.vec_neg(vec)); }
ezSATvec operator &(const ezSATvec &other) { return ezSATvec(sat, sat.vec_and(vec, other.vec)); }
ezSATvec operator |(const ezSATvec &other) { return ezSATvec(sat, sat.vec_or(vec, other.vec)); }
ezSATvec operator ^(const ezSATvec &other) { return ezSATvec(sat, sat.vec_xor(vec, other.vec)); }