int
main (void)
{
Btor *btor;
BtorNode *x, *y, *temp, *old_x, *old_y, *eq1, *eq2, *and, *formula;
int result;
btor = boolector_new ();
x = boolector_var (btor, BV1_EXAMPLE_NUM_BITS, NULL);
y = boolector_var (btor, BV1_EXAMPLE_NUM_BITS, NULL);
/* remember initial values of x and y */
old_x = boolector_copy (btor, x);
old_y = boolector_copy (btor, y);
/* x = x ^ y */
temp = boolector_xor (btor, x, y);
boolector_release (btor, x);
x = temp;
/* y = x ^ y */
temp = boolector_xor (btor, x, y);
boolector_release (btor, y);
y = temp;
/* x = x ^ y */
temp = boolector_xor (btor, x, y);
boolector_release (btor, x);
x = temp;
/* Now, we have to show that old_x = y and old_y = x */
eq1 = boolector_eq (btor, old_x, y);
eq2 = boolector_eq (btor, old_y, x);
and = boolector_and (btor, eq1, eq2);
/* In order to prove that this is a theorem, we negate the whole
* formula and show that the negation is unsatisfiable */
formula = boolector_not (btor, and);
/* We assert the formula and call Boolector */
boolector_assert (btor, formula);
result = boolector_sat (btor);
if (result == BOOLECTOR_UNSAT)
printf ("Formula is unsatisfiable\n");
else
abort ();
/* cleanup */
boolector_release (btor, x);
boolector_release (btor, old_x);
boolector_release (btor, y);
boolector_release (btor, old_y);
boolector_release (btor, eq1);
boolector_release (btor, eq2);
boolector_release (btor, and);
boolector_release (btor, formula);
assert (boolector_get_refs (btor) == 0);
boolector_delete (btor);
return 0;
}
void
V3SvrBoolector::add_FF_Formula(const V3NetId& out, const uint32_t& depth) {
// Check Output Validation
assert (validNetId(out)); assert (V3_FF == _ntk->getGateType(out)); assert (!getVerifyData(out, depth));
const uint32_t index = getV3NetIndex(out); assert (depth == _ntkData[index].size());
const uint32_t width = _ntk->getNetWidth(out); assert (width);
if (_freeBound) {
// Set BtorExp*
_ntkData[index].push_back(boolector_var(_Solver, width, NULL));
}
else if (depth) {
// Build FF I/O Relation
const V3NetId in1 = _ntk->getInputNetId(out, 0); assert (validNetId(in1));
BtorExp* const exp1 = getVerifyData(in1, depth - 1); assert (exp1);
// Set BtorExp*
_ntkData[index].push_back(boolector_copy(_Solver, exp1));
}
else {
// Set BtorExp*
_ntkData[index].push_back(boolector_var(_Solver, width, NULL));
BtorExp* const exp = _ntkData[index].back(); assert (exp);
// Build FF Initial State
const V3NetId in1 = _ntk->getInputNetId(out, 1); assert (validNetId(in1));
const V3BvNtk* const ntk = dynamic_cast<const V3BvNtk*>(_ntk);
if (ntk) {
if (BV_CONST == ntk->getGateType(in1)) {
const V3BitVecX* const value = ntk->getInputConstValue(in1);
assert (value); assert (width == value->size());
char* bv_value = new char[width + 1]; bv_value[width] = '\0';
for (uint32_t i = 0, j = width - 1; i < width; ++i, --j) bv_value[j] = (*value)[i];
BtorExp* const init_exp = boolector_const(_Solver, bv_value); assert (init_exp);
_init.push_back(boolector_eq(_Solver, exp, init_exp));
delete[] bv_value; boolector_release(_Solver, init_exp);
}
else { // Build Initial Circuit
BtorExp* const exp1 = getVerifyData(in1, 0); assert (exp1);
_init.push_back(boolector_eq(_Solver, exp, exp1));
}
}
else {
if (AIG_FALSE == _ntk->getGateType(in1))
_init.push_back(!isV3NetInverted(in1) ? boolector_not(_Solver, exp) : boolector_copy(_Solver, exp));
else { // Build Initial Circuit
BtorExp* const exp1 = getVerifyData(in1, 0); assert (exp1);
_init.push_back(boolector_eq(_Solver, exp, exp1));
}
}
}
assert (getVerifyData(out, depth));
}
const size_t
V3SvrBoolector::setTargetValue(const V3NetId& id, const V3BitVecX& value, const uint32_t& depth, const size_t& prev) {
// Construct formula y = b0 & b1' & b3 & ... & bn', and return expr y
if (prev) assert (!isNegFormula(prev)); // Constrain input prev expr should NOT be negative!
uint32_t size = value.size(); assert (size == _ntk->getNetWidth(id));
BtorExp* const aExp = getVerifyData(id, depth); assert (aExp);
BtorExp* pExp = (prev) ? boolector_copy(_Solver, getOriExp(prev)) : 0, *bExp, *cExp, *eExp;
char* bv_value = new char[size + 1];
uint32_t i = size, j = 0;
while (i--) {
if ('1' == value[i]) bv_value[j++] = '1';
else if ('0' == value[i]) bv_value[j++] = '0';
else if (j) {
bv_value[j] = '\0';
bExp = boolector_slice(_Solver, aExp, i + j, i + 1);
cExp = boolector_const(_Solver, bv_value);
eExp = boolector_eq(_Solver, bExp, cExp);
boolector_release(_Solver, bExp);
boolector_release(_Solver, cExp);
if (pExp) {
bExp = boolector_and(_Solver, pExp, eExp);
boolector_release(_Solver, pExp);
boolector_release(_Solver, eExp);
pExp = bExp;
}
else pExp = eExp;
j = 0;
}
}
if (j) {
bv_value[j] = '\0';
if (j == size) bExp = boolector_copy(_Solver, aExp);
else bExp = boolector_slice(_Solver, aExp, j - 1, 0);
cExp = boolector_const(_Solver, bv_value);
eExp = boolector_eq(_Solver, bExp, cExp);
boolector_release(_Solver, bExp);
boolector_release(_Solver, cExp);
if (pExp) {
bExp = boolector_and(_Solver, pExp, eExp);
boolector_release(_Solver, pExp);
boolector_release(_Solver, eExp);
pExp = bExp;
}
else pExp = eExp;
}
delete[] bv_value;
assert (!isNegFormula(getPosExp(pExp)));
return getPosExp(pExp);
}
void
V3SvrBoolector::assumeProperty(const V3NetId& id, const bool& invert, const uint32_t& depth) {
assert (validNetId(id)); assert (1 == _ntk->getNetWidth(id));
BtorExp* const exp = getVerifyData(id, depth); assert (exp);
if (!invert) _assump.push_back(boolector_copy(_Solver, exp));
else _assump.push_back(boolector_not(_Solver, exp));
}
// Manipulation Helper Functions
void
V3SvrBoolector::setTargetValue(const V3NetId& id, const V3BitVecX& value, const uint32_t& depth, V3SvrDataVec& formula) {
// Note : This Function will set formula such that AND(formula) represents (id == value)
uint32_t size = value.size(); assert (size == _ntk->getNetWidth(id));
BtorExp* const aExp = getVerifyData(id, depth); assert (aExp);
char* bv_value = new char[size + 1];
BtorExp *bExp, *cExp;
uint32_t i = size, j = 0;
while (i--) {
if ('1' == value[i]) bv_value[j++] = '1';
else if ('0' == value[i]) bv_value[j++] = '0';
else if (j) {
bv_value[j] = '\0';
bExp = boolector_slice(_Solver, aExp, i + j, i + 1);
cExp = boolector_const(_Solver, bv_value); j = 0;
formula.push_back(getPosExp(boolector_eq(_Solver, bExp, cExp)));
boolector_release(_Solver, bExp); boolector_release(_Solver, cExp);
}
}
if (j) {
bv_value[j] = '\0';
if (j == size) bExp = boolector_copy(_Solver, aExp);
else bExp = boolector_slice(_Solver, aExp, j - 1, 0);
cExp = boolector_const(_Solver, bv_value);
formula.push_back(getPosExp(boolector_eq(_Solver, bExp, cExp)));
boolector_release(_Solver, bExp); boolector_release(_Solver, cExp);
}
delete[] bv_value;
}
const size_t
V3SvrBoolector::setImplyIntersection(const V3SvrDataVec& Exps) {
if (Exps.size() == 0) return 0;
vector<size_t>::const_iterator it = Exps.begin(); assert (*it);
BtorExp *aExp = (isNegFormula(*it) ? boolector_not(_Solver, getOriExp(*it)) : boolector_copy(_Solver, getOriExp(*it)));
BtorExp *bExp, *oExp; ++it;
for (; it != Exps.end(); ++it) {
assert (*it); assert (aExp);
bExp = (isNegFormula(*it) ? boolector_not(_Solver, getOriExp(*it)) : boolector_copy(_Solver, getOriExp(*it)));
oExp = boolector_and(_Solver, aExp, bExp); assert (oExp);
boolector_release(_Solver, aExp);
boolector_release(_Solver, bExp);
aExp = oExp;
}
bExp = boolector_var(_Solver, 1, NULL);
oExp = boolector_implies(_Solver, bExp, aExp);
boolector_assert(_Solver, oExp);
boolector_release(_Solver, oExp);
boolector_release(_Solver, aExp);
assert (!isNegFormula(getPosExp(bExp)));
assert (bExp); return getPosExp(bExp);
}
void
V3SvrBoolector::assumeProperty(const size_t& exp, const bool& invert) {
_assump.push_back(invert ^ isNegFormula(exp) ? boolector_not(_Solver, getOriExp(exp)) :
boolector_copy(_Solver, getOriExp(exp)));
}
void
V3SvrBoolector::assumeInit() {
for (uint32_t i = 0; i < _init.size(); ++i) _assump.push_back(boolector_copy(_Solver, _init[i]));
}
