Z3() {
expressionCache = new HashMap<Integer, BoolExpr>();
try {
context = new Context();
satTactic = context.ParAndThen(context.MkTactic("sat-preprocess"), context.MkTactic("sat"));
solver = context.MkSolver(satTactic);
} catch (Z3Exception e) {
throw new RuntimeException(e);
}
this.vars = 0;
this.clauses = 0;
this.last_status = null;
this.last_model = null;
checkpoints = new Stack<Checkpoint>();
}
/**
* {@inheritDoc}
*
* @see kodkod.engine.satlab.SATSolver#free()
*/
public final synchronized void free() {
checkpoints = null;
solver = null;
context.Dispose();
context = null;
expressionCache = null;
}
/**
* {@inheritDoc}
*
* @see kodkod.engine.satlab.SATSolver#addClause(int[])
*/
public boolean addClause(int[] lits) {
if (lits == null) {
throw new NullPointerException();
}
try {
BoolExpr[] literals = new BoolExpr[lits.length];
for (int i = 0; i < lits.length; i += 1) {
int lit = Math.abs(lits[i]);
if (lit == 0 || lit > vars) {
throw new IllegalArgumentException("Illegal variable: " + lit);
}
literals[i] = getExpressionForLiteral(lits[i]);
}
BoolExpr clause = context.MkOr(literals);
solver.Assert(clause);
clauses += 1;
} catch (Z3Exception e) {
throw new RuntimeException(e);
}
return true;
}
private BoolExpr getExpressionForLiteral(int literal) throws Z3Exception {
if (literal == 0) {
throw new IllegalArgumentException("Parameter must be nonzero.");
}
BoolExpr expr = expressionCache.get(literal);
if (expr == null) {
if (literal > 0) {
Symbol sym = context.MkSymbol(literal);
expr = context.MkBoolConst(sym);
} else {
expr = context.MkNot(getExpressionForLiteral(-literal));
}
expressionCache.put(literal, expr);
}
return expr;
}
private boolean checkQueryWithLibrary(String query, int timeout) {
boolean result = false;
try {
com.microsoft.z3.Context context = new com.microsoft.z3.Context();
Solver solver = context.mkSolver();
Params params = context.mkParams();
params.add("timeout", timeout);
solver.setParameters(params);
solver.add(context.parseSMTLIB2String(SMT_PRELUDE + query, null, null, null, null));
result = solver.check() == Status.UNSATISFIABLE;
context.dispose();
} catch (Z3Exception e) {
kem.registerCriticalWarning("failed to translate smtlib expression:\n" + SMT_PRELUDE + query);
} catch (UnsatisfiedLinkError e) {
System.err.println(System.getProperty("java.library.path"));
throw e;
}
return result;
}
