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//-----------------------------------------------------------------------------
//
// Copyright (C) Microsoft Corporation. All Rights Reserved.
//
//-----------------------------------------------------------------------------
using Microsoft.Boogie;
using AI = Microsoft.AbstractInterpretationFramework;
using System.Diagnostics.Contracts;
using Microsoft.Basetypes;
namespace Microsoft.Boogie.AbstractInterpretation {
public class BoogiePropFactory : BoogieFactory, AI.IQuantPropExprFactory {
public AI.IFunApp False {
get {
Contract.Ensures(Contract.Result<AI.IFunApp>() != null);
return Expr.False;
}
}
public AI.IFunApp True {
get {
Contract.Ensures(Contract.Result<AI.IFunApp>() != null);
return Expr.True;
}
}
public AI.IFunApp Not(AI.IExpr p) {
//Contract.Requires(p != null);
Contract.Ensures(Contract.Result<AI.IFunApp>() != null);
return Expr.Unary(Token.NoToken, UnaryOperator.Opcode.Not, IExpr2Expr(p));
}
public AI.IFunApp And(AI.IExpr p, AI.IExpr q) {
//Contract.Requires(p != null);
//Contract.Requires(q != null);
Contract.Ensures(Contract.Result<AI.IFunApp>() != null);
return Expr.Binary(BinaryOperator.Opcode.And, IExpr2Expr(p), IExpr2Expr(q));
}
public AI.IFunApp Or(AI.IExpr p, AI.IExpr q) {
//Contract.Requires(p != null);
//Contract.Requires(q != null);
Contract.Ensures(Contract.Result<AI.IFunApp>() != null);
return Expr.Binary(BinaryOperator.Opcode.Or, IExpr2Expr(p), IExpr2Expr(q));
}
public AI.IFunApp Implies(AI.IExpr p, AI.IExpr q) {
//Contract.Requires(p != null);
//Contract.Requires(q != null);
Contract.Ensures(Contract.Result<AI.IFunApp>() != null);
return Expr.Binary(BinaryOperator.Opcode.Imp, IExpr2Expr(p), IExpr2Expr(q));
}
public AI.IFunApp Exists(AI.IFunction p) {
//Contract.Requires(p != null);
Contract.Ensures(Contract.Result<AI.IFunApp>() != null);
return (AI.IFunApp)(new ExistsExpr(Token.NoToken, new VariableSeq((Variable)p.Param), IExpr2Expr(p.Body))).IExpr;
}
public AI.IFunApp Exists(AI.AIType paramType, AI.FunctionBody bodygen) {
//Contract.Requires(bodygen != null);
Contract.Ensures(Contract.Result<AI.IFunApp>() != null);
// generate a fresh new variable
Variable var = FreshBoundVariable(paramType);
Contract.Assert(var != null);
Expr expr = IExpr2Expr(bodygen(var));
Contract.Assert(expr != null);
return (AI.IFunApp)(new ExistsExpr(Token.NoToken, new VariableSeq(var), expr)).IExpr;
}
public AI.IFunApp Forall(AI.IFunction p) {
//Contract.Requires(p != null);
Contract.Ensures(Contract.Result<AI.IFunApp>() != null);
return (AI.IFunApp)(new ForallExpr(Token.NoToken, new VariableSeq((Variable)p.Param), IExpr2Expr(p.Body))).IExpr;
}
public AI.IFunApp Forall(AI.AIType paramType, AI.FunctionBody bodygen) {
//Contract.Requires(bodygen != null);
Contract.Ensures(Contract.Result<AI.IFunApp>() != null);
// generate a fresh new variable
Variable var = FreshBoundVariable(paramType);
Contract.Assert(var != null);
Expr expr = IExpr2Expr(bodygen(var));
Contract.Assert(expr != null);
return (AI.IFunApp)(new ForallExpr(Token.NoToken, new VariableSeq(var), expr)).IExpr;
}
private static int freshVarNum = 0;
private static Variable FreshBoundVariable(AI.AIType paramType) {
Contract.Ensures(Contract.Result<Variable>() != null);
// TODO: Should use the AI.AIType given in Exists and Forall to determine what Boogie type
// to make this new variable? For now, we use Type.Any.
Type t = Type.Int;
Contract.Assert(t != null);
/*
if (paramType is AI.Ref)
t = Type.Ref;
else if (paramType is AI.FieldName)
t = Type.Name;
else
System.Console.WriteLine("*** unsupported type in AI {0}", paramType); */
Contract.Assert(false);
throw new cce.UnreachableException();
TypedIdent id = new TypedIdent(Token.NoToken, "propfactory_freshvar" + freshVarNum, t);
freshVarNum++;
return new BoundVariable(Token.NoToken, id);
}
}
public class BoogieValueFactory : BoogieFactory, AI.IValueExprFactory {
public AI.IFunApp Eq(AI.IExpr e0, AI.IExpr e1) {
//Contract.Requires(e0 != null);
//Contract.Requires(e1 != null);
Contract.Ensures(Contract.Result<AI.IFunApp>() != null);
return Expr.Eq(IExpr2Expr(e0), IExpr2Expr(e1));
}
public AI.IFunApp Neq(AI.IExpr e0, AI.IExpr e1) {
//Contract.Requires(e0 != null);
//Contract.Requires(e1 != null);
Contract.Ensures(Contract.Result<AI.IFunApp>() != null);
return Expr.Neq(IExpr2Expr(e0), IExpr2Expr(e1));
}
}
public class BoogieNullnessFactory : BoogieFactory, AI.INullnessFactory {
public AI.IFunApp Eq(AI.IExpr e0, AI.IExpr e1) {
//Contract.Requires(e0 != null);
//Contract.Requires(e1 != null);
Contract.Ensures(Contract.Result<AI.IFunApp>() != null);
return Expr.Eq(IExpr2Expr(e0), IExpr2Expr(e1));
}
public AI.IFunApp Neq(AI.IExpr e0, AI.IExpr e1) {
//Contract.Requires(e0 != null);
//Contract.Requires(e1 != null);
Contract.Ensures(Contract.Result<AI.IFunApp>() != null);
return Expr.Neq(IExpr2Expr(e0), IExpr2Expr(e1));
}
public AI.IFunApp Null {
get {
Contract.Assert(false); // don't know where to get null from\
throw new cce.UnreachableException();
}
}
}
public class BoogieIntFactory : BoogieValueFactory, AI.IIntExprFactory {
public AI.IFunApp Const(BigNum i) {
Contract.Ensures(Contract.Result<AI.IFunApp>() != null);
return new LiteralExpr(Token.NoToken, i);
}
}
public class BoogieLinearFactory : BoogieIntFactory, AI.ILinearExprFactory {
public AI.IFunApp AtMost(AI.IExpr e0, AI.IExpr e1) {
//Contract.Requires(e0 != null);
//Contract.Requires(e1 != null);
Contract.Ensures(Contract.Result<AI.IFunApp>() != null);
return Expr.Le(IExpr2Expr(e0), IExpr2Expr(e1));
}
public AI.IFunApp Add(AI.IExpr e0, AI.IExpr e1) {
//Contract.Requires(e0 != null);
//Contract.Requires(e1 != null);
Contract.Ensures(Contract.Result<AI.IFunApp>() != null);
return Expr.Add(IExpr2Expr(e0), IExpr2Expr(e1));
}
public AI.IExpr Term(Rational r, AI.IVariable var) {
Contract.Ensures(Contract.Result<AI.IExpr>() != null);
if (var != null && r == Rational.ONE) {
return var;
} else {
Expr product;
if (r.IsIntegral) {
product = Expr.Literal(r.AsBigNum);
} else {
product = Expr.Div(Expr.Literal(r.Numerator), Expr.Literal(r.Denominator));
}
if (var != null) {
product = Expr.Mul(product, IExpr2Expr(var));
}
return product.IExpr;
}
}
public AI.IFunApp False {
get {
Contract.Ensures(Contract.Result<AI.IFunApp>() != null);
return Expr.False;
}
}
public AI.IFunApp True {
get {
Contract.Ensures(Contract.Result<AI.IFunApp>() != null);
return Expr.True;
}
}
public AI.IFunApp And(AI.IExpr p, AI.IExpr q) {
//Contract.Requires(p != null);
//Contract.Requires(q != null);
Contract.Ensures(Contract.Result<AI.IFunApp>() != null);
return Expr.Binary(BinaryOperator.Opcode.And, IExpr2Expr(p), IExpr2Expr(q));
}
}
public class BoogieTypeFactory : BoogieFactory, AI.ITypeExprFactory {
/// <summary>
/// Returns an expression denoting the top of the type hierarchy.
/// </summary>
public AI.IExpr RootType {
get {
Contract.Assert(false); // BUGBUG: TODO
throw new System.NotImplementedException();
}
}
/// <summary>
/// Returns true iff "t" denotes a type constant.
/// </summary>
[Pure]
public bool IsTypeConstant(AI.IExpr t) {
//Contract.Requires(t != null);
Contract.Ensures(Contract.Result<bool>() == (t is Constant));
return t is Constant;
}
/// <summary>
/// Returns true iff t0 and t1 are types such that t0 and t1 are equal.
/// </summary>
[Pure]
public bool IsTypeEqual(AI.IExpr t0, AI.IExpr t1) {
//Contract.Requires(t0 != null);
//Contract.Requires(t1 != null);
Constant c0 = t0 as Constant;
Constant c1 = t1 as Constant;
return c0 != null && c1 != null && c0 == c1;
}
/// <summary>
/// Returns true iff t0 and t1 are types such that t0 is a subtype of t1.
/// </summary>
[Pure]
public bool IsSubType(AI.IExpr t0, AI.IExpr t1) {
//Contract.Requires(t0 != null);
//Contract.Requires(t1 != null);
Contract.Assert(false); // BUGBUG: TODO
throw new cce.UnreachableException();
}
/// <summary>
/// Returns the most derived supertype of both "t0" and "t1". A precondition is
/// that "t0" and "t1" both represent types.
/// </summary>
public AI.IExpr JoinTypes(AI.IExpr t0, AI.IExpr t1) {
//Contract.Requires(t0 != null);
//Contract.Requires(t1 != null);
Contract.Ensures(Contract.Result<AI.IExpr>() != null);
Contract.Assert(false); // BUGBUG: TODO
throw new cce.UnreachableException();
}
public AI.IFunApp IsExactlyA(AI.IExpr e, AI.IExpr type) {
//PM: We need this assume because Boogie does not yet allow us to use the
//PM: inherited precondition "requires IsTypeConstant(type)".
//PM: Note that that precondition is currently commented out.
//Contract.Requires(e != null);
//Contract.Requires(type != null);
Contract.Ensures(Contract.Result<AI.IFunApp>() != null);
Contract.Assume(type is Constant);
Constant theType = (Constant)type;
Contract.Assert(false);
throw new cce.UnreachableException();
Expr typeofExpr = new NAryExpr(Token.NoToken,
new FunctionCall(new IdentifierExpr(Token.NoToken, "$typeof", Type.Int // Name
)),
new ExprSeq(IExpr2Expr(e)));
return Expr.Eq(typeofExpr, Expr.Ident(theType));
}
public AI.IFunApp IsA(AI.IExpr e, AI.IExpr type) {
//Contract.Requires(e != null);
//Contract.Requires(type != null);
Contract.Ensures(Contract.Result<AI.IFunApp>() != null);
//PM: We need this assume because Boogie does not yet allow us to use the
//PM: inherited precondition "requires IsTypeConstant(type)".
//PM: Note that that precondition is currently commented out.
Contract.Assume(type is Constant);
Contract.Assert(false);
throw new cce.UnreachableException();
Expr typeofExpr = new NAryExpr(Token.NoToken,
new FunctionCall(new IdentifierExpr(Token.NoToken, "$typeof", Type.Int // Name
)),
new ExprSeq(IExpr2Expr(e)));
return new NAryExpr(Token.NoToken,
new BinaryOperator(Token.NoToken, BinaryOperator.Opcode.Subtype),
new ExprSeq(typeofExpr, IExpr2Expr(e)));
}
}
}
|
