public VCExpr get(Term arg)
{
if (memo.ContainsKey(arg))
{
return(memo[arg]);
}
VCExpr res = null;
switch (arg.GetKind())
{
case TermKind.Numeral:
var numstr = arg.GetNumeralString();
if (arg.GetSort().GetSortKind() == SortKind.Int)
{
res = gen.Integer(Basetypes.BigNum.FromString(numstr));
}
else
{
res = gen.Real(Basetypes.BigDec.FromString(numstr));
}
break;
case TermKind.App:
var args = arg.GetAppArgs();
var vcargs = new VCExpr[args.Length];
for (int i = 0; i < args.Length; i++)
{
vcargs[i] = get(args[i]);
}
switch (arg.GetAppDecl().GetKind())
{
case DeclKind.Add:
if (vcargs.Length == 0)
{
if (arg.GetSort().GetSortKind() == SortKind.Int)
{
res = gen.Integer(Basetypes.BigNum.ZERO);
}
else
{
res = gen.Real(Basetypes.BigDec.ZERO);
}
}
else
{
res = vcargs[0];
for (int k = 1; k < vcargs.Length; k++)
{
res = gen.Add(res, vcargs[k]);
}
}
break;
case DeclKind.And:
res = VCExpressionGenerator.True;
for (int i = 0; i < vcargs.Length; i++)
{
res = gen.AndSimp(res, vcargs[i]);
}
break;
case DeclKind.Div:
Debug.Assert(vcargs.Length == 2);
res = gen.Function(VCExpressionGenerator.RealDivOp, vcargs[0], vcargs[1]);
break;
case DeclKind.Eq:
Debug.Assert(vcargs.Length == 2);
res = gen.Eq(vcargs[0], vcargs[1]);
break;
case DeclKind.False:
res = VCExpressionGenerator.False;
break;
case DeclKind.Ge:
Debug.Assert(vcargs.Length == 2);
res = gen.Function(VCExpressionGenerator.GeOp, vcargs[0], vcargs[1]);
break;
case DeclKind.Gt:
Debug.Assert(vcargs.Length == 2);
res = gen.Gt(vcargs[0], vcargs[1]);
break;
case DeclKind.IDiv:
Debug.Assert(vcargs.Length == 2);
res = gen.Function(VCExpressionGenerator.DivOp, vcargs[0], vcargs[1]);
break;
case DeclKind.Iff:
Debug.Assert(vcargs.Length == 2);
var l = create_let(args[0], vcargs[0]);
var r = create_let(args[1], vcargs[1]);
return(gen.And(gen.Implies(l, r), gen.Implies(r, l)));
case DeclKind.Implies:
Debug.Assert(vcargs.Length == 2);
res = gen.Implies(vcargs[0], vcargs[1]);
break;
case DeclKind.Ite:
Debug.Assert(vcargs.Length == 3);
res = gen.Function(VCExpressionGenerator.IfThenElseOp, vcargs[0], vcargs[1], vcargs[2]);
break;
case DeclKind.Le:
Debug.Assert(vcargs.Length == 2);
res = gen.Function(VCExpressionGenerator.LeOp, vcargs[0], vcargs[1]);
break;
case DeclKind.Lt:
Debug.Assert(vcargs.Length == 2);
res = gen.Function(VCExpressionGenerator.LtOp, vcargs[0], vcargs[1]);
break;
case DeclKind.Mod:
Debug.Assert(vcargs.Length == 2);
res = gen.Function(VCExpressionGenerator.ModOp, vcargs[0], vcargs[1]);
break;
case DeclKind.Mul:
Debug.Assert(vcargs.Length == 2);
res = gen.Function(VCExpressionGenerator.MulOp, vcargs[0], vcargs[1]);
break;
case DeclKind.Not:
Debug.Assert(vcargs.Length == 1);
res = gen.Not(vcargs[0]);
break;
case DeclKind.Or:
res = VCExpressionGenerator.False;
for (int i = 0; i < vcargs.Length; i++)
{
res = gen.OrSimp(res, vcargs[i]);
}
break;
case DeclKind.Select:
Debug.Assert(vcargs.Length == 2);
res = gen.Select(vcargs[0], vcargs[1]);
break;
case DeclKind.Store:
Debug.Assert(vcargs.Length == 3);
res = gen.Store(vcargs[0], vcargs[1], vcargs[2]);
break;
case DeclKind.Sub:
Debug.Assert(vcargs.Length == 2);
res = gen.Function(VCExpressionGenerator.SubOp, vcargs[0], vcargs[1]);
break;
case DeclKind.True:
res = VCExpressionGenerator.True;
break;
case DeclKind.Uminus:
Debug.Assert(vcargs.Length == 1);
var argzero = null;
if (vcargs[0].Type.IsInt)
{
argzero = gen.Integer(Basetypes.BigNum.ZERO);
}
else
{
argzero = gen.Real(Basetypes.BigDec.ZERO);
}
res = gen.Function(VCExpressionGenerator.SubOp, argzero, vcargs[0]);
break;
case DeclKind.ToInt:
Debug.Assert(vcargs.Length == 1);
res = gen.Function(VCExpressionGenerator.ToIntOp, vcargs[0]);
break;
case DeclKind.ToReal:
Debug.Assert(vcargs.Length == 1);
res = gen.Function(VCExpressionGenerator.ToRealOp, vcargs[0]);
break;
case DeclKind.Uninterpreted:
var name = arg.GetAppDecl().GetDeclName();
if (args.Length == 0)
{ // a 0-ary constant is a VCExprVar
if (!constants_inv.TryGetValue(arg, out res))
{
throw new Exception("Z3 returned unknown constant: " + name);
}
}
else
{
Function f;
if (!functions_inv.TryGetValue(arg.GetAppDecl(), out f))
{
throw new Exception("Z3 returned unknown function: " + name);
}
List <VCExpr> vcargsList = new List <VCExpr>(vcargs);
res = gen.Function(f, vcargsList);
}
break;
default:
throw new Exception("Unknown Z3 operator");
}
break;
default:
Debug.Assert(false);
throw new Exception("Unknown Z3 AST kind");
}
memo.Add(arg, res);
return(res);
}
private static VCExpr ToVcExpr(Expr expr, Dictionary <string, VCExpr> incarnations, VCExpressionGenerator gen)
{
if (expr is LiteralExpr)
{
var val = (expr as LiteralExpr).Val;
if (val is bool)
{
if ((bool)val)
{
return(VCExpressionGenerator.True);
}
else
{
return(VCExpressionGenerator.False);
}
}
else if (val is Microsoft.Basetypes.BigNum)
{
return(gen.Integer((Microsoft.Basetypes.BigNum)val));
}
throw new NotImplementedException("Cannot handle literals of this type");
}
if (expr is IdentifierExpr)
{
return(ToVcVar((expr as IdentifierExpr).Name, incarnations, false));
}
if (expr is OldExpr)
{
var ide = (expr as OldExpr).Expr as IdentifierExpr;
Debug.Assert(ide != null);
return(ToVcVar(ide.Name, incarnations, true));
}
if (expr is NAryExpr)
{
var nary = expr as NAryExpr;
if (nary.Fun is UnaryOperator)
{
if ((nary.Fun as UnaryOperator).Op == UnaryOperator.Opcode.Not)
{
return(gen.Not(ToVcExpr(nary.Args[0], incarnations, gen)));
}
else if ((nary.Fun as UnaryOperator).Op == UnaryOperator.Opcode.Neg)
{
return(gen.Function(VCExpressionGenerator.SubIOp, gen.Integer(Microsoft.Basetypes.BigNum.FromInt(0)), ToVcExpr(nary.Args[0], incarnations, gen)));
}
else
{
Debug.Assert(false, "No other unary op is handled");
}
}
if (nary.Fun is BinaryOperator)
{
return(gen.Function(Translate(nary.Fun as BinaryOperator), ToVcExpr(nary.Args[0], incarnations, gen), ToVcExpr(nary.Args[1], incarnations, gen)));
}
if (nary.Fun is MapSelect && nary.Args.Count == 2)
{
return(gen.Select(ToVcExpr(nary.Args[0], incarnations, gen), ToVcExpr(nary.Args[1], incarnations, gen)));
}
Debug.Assert(false, "No other op is handled");
}
throw new NotImplementedException(string.Format("Expr of type {0} is not handled", expr.GetType().ToString()));
}