// returns whether the error condition is satisfiable within frame.
bool TestErrorSatisfiable(CheckerState *state, CheckerFrame *frame, Bit *bit)
{
BlockMemory *mcfg = frame->Memory();
Solver *solver = state->GetSolver();
if (!solver->IsSatisfiable()) {
if (checker_verbose.IsSpecified())
logout << "CHECK: " << frame << ": Guard unsatisfiable: " << bit
<< " [" << bit->Hash() << "]" << endl;
return false;
}
state->PushContext();
state->AssertBaseBits();
if (!solver->IsSatisfiable()) {
if (checker_verbose.IsSpecified())
logout << "CHECK: " << frame << ": Error unsatisfiable: " << bit
<< " [" << bit->Hash() << "]" << endl;
state->PopContext();
return false;
}
if (!frame->m_checked_assertions) {
frame->m_checked_assertions = true;
// check to see if the error is contradicted by previous assertions
// in this frame. assert the previous assertions, but don't keep
// them around past this function to avoid polluting the solver
// with worthless extra checks.
BlockSummary *sum = GetBlockSummary(mcfg->GetId());
const Vector<AssertInfo> *asserts = sum->GetAsserts();
size_t assert_count = VectorSize<AssertInfo>(asserts);
for (size_t ind = 0; ind < assert_count; ind++) {
const AssertInfo &info = asserts->At(ind);
// only use the same kind of assertion to check for redundancy.
if (info.kind != state->GetAssertKind())
continue;
if (info.cls != ASC_Check)
continue;
if (info.point < frame->EndPoint()) {
// get the asserted condition relative to block entry.
Bit *assert_value;
mcfg->TranslateBit(TRK_Point, info.point, info.bit, &assert_value);
assert_value->MoveRef(&assert_value, NULL);
Bit *point_guard = mcfg->GetGuard(info.point);
point_guard->IncRef();
Bit *imply_assert =
Bit::MakeImply(point_guard, assert_value);
solver->AddConstraint(frame->Id(), imply_assert);
}
}
sum->DecRef();
if (!solver->IsSatisfiable()) {
if (checker_verbose.IsSpecified())
logout << "CHECK: " << frame
<< ": Unsatisfiable from assertions" << endl;
state->PopContext();
return false;
}
}
state->PopContext();
return true;
}
