internal Bpl.Expr BplBvLiteralExpr(Bpl.IToken tok, BaseTypes.BigNum n, int width)
{
Contract.Requires(tok != null);
Contract.Requires(0 <= width);
if (width == 0)
{
// see comment in BplBvType
Contract.Assert(n.IsZero);
return(Bpl.Expr.Literal(0));
}
else if (n.IsNegative)
{
// This can only happen if some error is reported elsewhere. Nevertheless, we do need to
// generate a Boogie expression and Boogie would crash if we pass a negative number to
// Bpl.LiteralExpr for a bitvector.
var zero = new Bpl.LiteralExpr(tok, BaseTypes.BigNum.ZERO, width);
var absN = new Bpl.LiteralExpr(tok, -n, width);
var etran = new ExpressionTranslator(this, predef, tok);
return(etran.TrToFunctionCall(tok, "sub_bv" + width, BplBvType(width), zero, absN, false));
}
else
{
return(new Bpl.LiteralExpr(tok, n, width));
}
}
public Bpl.AssignCmd createBoogieNavigationUpdateCmd(Sink sink)
{
// the block is a potential page changer
List <Bpl.AssignLhs> lhs = new List <Bpl.AssignLhs>();
List <Bpl.Expr> rhs = new List <Bpl.Expr>();
Bpl.Expr value = new Bpl.LiteralExpr(Bpl.Token.NoToken, false);
rhs.Add(value);
Bpl.SimpleAssignLhs assignee =
new Bpl.SimpleAssignLhs(Bpl.Token.NoToken,
new Bpl.IdentifierExpr(Bpl.Token.NoToken,
sink.FindOrCreateGlobalVariable(PhoneCodeHelper.BOOGIE_CONTINUE_ON_PAGE_VARIABLE, Bpl.Type.Bool)));
lhs.Add(assignee);
Bpl.AssignCmd assignCmd = new Bpl.AssignCmd(Bpl.Token.NoToken, lhs, rhs);
return(assignCmd);
}
private void _PositiveBV(int decimalValue, int width, string expectedString)
{
Assert.IsTrue(decimalValue >= 0);
var builder = GetSimpleBuilder();
// Test both versions of the API
var constants = new Microsoft.Boogie.LiteralExpr[] {
builder.ConstantBV(decimalValue, width),
builder.ConstantBV(new BigInteger(decimalValue), width)
};
foreach (var constant in constants)
{
Assert.AreEqual(expectedString, constant.ToString());
CheckType(constant, t => t.IsBv);
Assert.AreEqual(width, constant.asBvConst.Bits);
Assert.AreEqual(width, constant.Type.BvBits);
Assert.AreEqual(decimalValue, constant.asBvConst.Value.ToInt);
}
}
public void _NegativeBV(int decimalValue, int width, string expectedString)
{
Assert.IsTrue(decimalValue <= 0);
var builder = GetSimpleBuilder();
// Test both versions of the API
var constants = new Microsoft.Boogie.LiteralExpr[] {
builder.ConstantBV(decimalValue, width),
builder.ConstantBV(new BigInteger(decimalValue), width)
};
foreach (var constant in constants)
{
Assert.AreEqual(expectedString, constant.ToString());
CheckType(constant, t => t.IsBv);
Assert.AreEqual(width, constant.asBvConst.Bits);
Assert.AreEqual(width, constant.Type.BvBits);
// Compute decimal representation of two's complement bv
var MaxValuePlusOne = BigInteger.Pow(2, width);
var expectedValue = (MaxValuePlusOne + decimalValue) % MaxValuePlusOne;
Assert.AreEqual(expectedValue, constant.asBvConst.Value.ToBigInteger);
}
}
public Bpl.AssignCmd createBoogieNavigationUpdateCmd(Sink sink) {
// the block is a potential page changer
List<Bpl.AssignLhs> lhs = new List<Bpl.AssignLhs>();
List<Bpl.Expr> rhs = new List<Bpl.Expr>();
Bpl.Expr value = new Bpl.LiteralExpr(Bpl.Token.NoToken, false);
rhs.Add(value);
Bpl.SimpleAssignLhs assignee =
new Bpl.SimpleAssignLhs(Bpl.Token.NoToken,
new Bpl.IdentifierExpr(Bpl.Token.NoToken,
sink.FindOrCreateGlobalVariable(PhoneCodeHelper.BOOGIE_CONTINUE_ON_PAGE_VARIABLE, Bpl.Type.Bool)));
lhs.Add(assignee);
Bpl.AssignCmd assignCmd = new Bpl.AssignCmd(Bpl.Token.NoToken, lhs, rhs);
return assignCmd;
}
