Examples with Expr com.google.api.expr.v1alpha1.Expr used on opensource projects

Example 16 with Expr

use of com.google.api.expr.v1alpha1.Expr in project java-smt by sosy-lab.

the class CVC4BitvectorFormulaManager method divide.

@Override
protected Expr divide(Expr numerator, Expr denumerator, boolean signed) {
    final Kind operator = signed ? Kind.BITVECTOR_SDIV : Kind.BITVECTOR_UDIV;
    final Expr division = exprManager.mkExpr(operator, numerator, denumerator);
    // CVC4 does not align with SMTLIB standard when it comes to divide-by-zero.
    // For divide-by-zero, we compute the result as: return "1" with the opposite
    // sign than the numerator.
    final int bitsize = ((BitvectorType) formulaCreator.getFormulaType(numerator)).getSize();
    final Expr zero = makeBitvectorImpl(bitsize, 0);
    final Expr one = makeBitvectorImpl(bitsize, 1);
    // all bits equal "1"
    final Expr maxValue = makeBitvectorImpl(bitsize, -1);
    return exprManager.mkExpr(Kind.ITE, exprManager.mkExpr(Kind.EQUAL, denumerator, zero), exprManager.mkExpr(Kind.ITE, lessThan(numerator, zero, signed), one, maxValue), division);
}

Example 17 with Expr

use of com.google.api.expr.v1alpha1.Expr in project java-smt by sosy-lab.

the class CVC4BitvectorFormulaManager method modulo.

@Override
protected Expr modulo(Expr numerator, Expr denumerator, boolean signed) {
    final Kind operator = signed ? Kind.BITVECTOR_SREM : Kind.BITVECTOR_UREM;
    final Expr remainder = exprManager.mkExpr(operator, numerator, denumerator);
    // CVC4 does not align with SMTLIB standard when it comes to modulo-by-zero.
    // For modulo-by-zero, we compute the result as: "return the numerator".
    final int bitsize = ((BitvectorType) formulaCreator.getFormulaType(numerator)).getSize();
    final Expr zero = makeBitvectorImpl(bitsize, 0);
    return exprManager.mkExpr(Kind.ITE, exprManager.mkExpr(Kind.EQUAL, denumerator, zero), numerator, remainder);
}

Example 18 with Expr

use of com.google.api.expr.v1alpha1.Expr in project java-smt by sosy-lab.

the class CVC4FormulaCreator method makeVariable.

@Override
public Expr makeVariable(Type type, String name) {
    Expr exp = variablesCache.computeIfAbsent(name, n -> exprManager.mkVar(name, type));
    Preconditions.checkArgument(type.equals(exp.getType()), "symbol name already in use for different type %s", exp.getType());
    return exp;
}

Example 19 with Expr

use of com.google.api.expr.v1alpha1.Expr in project java-smt by sosy-lab.

the class CVC4FormulaCreator method declareUFImpl.

@Override
public Expr declareUFImpl(String pName, Type pReturnType, List<Type> pArgTypes) {
    Expr exp = functionsCache.get(pName);
    if (exp == null) {
        vectorType args = new vectorType();
        for (Type t : pArgTypes) {
            args.add(t);
        }
        exp = exprManager.mkVar(pName, exprManager.mkFunctionType(args, pReturnType));
        functionsCache.put(pName, exp);
    }
    return exp;
}

Example 20 with Expr

use of com.google.api.expr.v1alpha1.Expr in project java-smt by sosy-lab.

the class CVC4FormulaManager method dumpFormula.

@Override
public Appender dumpFormula(Expr f) {
    assert getFormulaCreator().getFormulaType(f) == FormulaType.BooleanType : "Only BooleanFormulas may be dumped";
    return new Appenders.AbstractAppender() {

        @Override
        public void appendTo(Appendable out) throws IOException {
            // get all symbols
            final Map<String, Expr> allVars = new LinkedHashMap<>();
            creator.extractVariablesAndUFs(f, true, allVars::put);
            // print all symbols
            for (Map.Entry<String, Expr> entry : allVars.entrySet()) {
                String name = entry.getKey();
                Expr var = entry.getValue();
                // escaping is stolen from SMTInterpol, lets hope this remains consistent
                out.append("(declare-fun ").append(PrintTerm.quoteIdentifier(name)).append(" (");
                // add function parameters
                Iterable<Type> childrenTypes = Iterables.transform(var, Expr::getType);
                out.append(Joiner.on(" ").join(childrenTypes));
                // and return type
                out.append(") ").append(var.getType().toString()).append(")\n");
            }
            // now add the final assert
            out.append("(assert ");
            // f.toStream() uses LET-expressions and is exactly what we want.
            try (OutputStream stream = new OutputStream() {

                @Override
                public void write(int chr) throws IOException {
                    out.append((char) chr);
                }
            }) {
                f.toStream(stream);
            }
            out.append(')');
        }
    };
}