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//-----------------------------------------------------------------------------
//
// Copyright (C) Microsoft Corporation. All Rights Reserved.
//
//-----------------------------------------------------------------------------
using System;
using System.Collections.Generic;
using System.IO;
using System.Text;
using System.Diagnostics.Contracts;
using Microsoft.Boogie.VCExprAST;
namespace Microsoft.Boogie
{
/// <summary>
/// The methods of this class are called in the following order:
/// DeclareType*
/// (DeclareConstant DeclareFunction)*
/// AddAxiom*
/// DeclareGlobalVariable*
/// At this time, all "attributes" are passed in as null.
/// </summary>
[ContractClass(typeof(ProverContextContracts))]
public abstract class ProverContext : ICloneable {
protected virtual void ProcessDeclaration(Declaration decl) {Contract.Requires(decl != null);}
public virtual void DeclareType(TypeCtorDecl t, string attributes) {Contract.Requires(t != null); ProcessDeclaration(t); }
public virtual void DeclareConstant(Constant c, bool uniq, string attributes) {Contract.Requires(c != null); ProcessDeclaration(c); }
public virtual void DeclareFunction(Function f, string attributes) {Contract.Requires(f != null); ProcessDeclaration(f); }
public virtual void AddAxiom(Axiom a, string attributes) {Contract.Requires(a != null); ProcessDeclaration(a); }
public virtual void DeclareGlobalVariable(GlobalVariable v, string attributes) {Contract.Requires(v != null); ProcessDeclaration(v); }
public abstract void AddAxiom(VCExpr vc);
public abstract string Lookup(VCExprVar var);
public abstract VCExpressionGenerator ExprGen { get; }
public abstract Boogie2VCExprTranslator BoogieExprTranslator { get; }
public abstract VCGenerationOptions VCGenOptions { get; }
public abstract object Clone();
}
[ContractClassFor(typeof(ProverContext))]
public abstract class ProverContextContracts:ProverContext{
public override void AddAxiom(VCExpr vc) {
}
public override void AddAxiom(Axiom a, string attributes)
{
}
public override VCExpressionGenerator ExprGen
{
get { Contract.Ensures(Contract.Result<VCExpressionGenerator>() != null);
throw new NotImplementedException(); }
}
public override Boogie2VCExprTranslator BoogieExprTranslator
{
get { Contract.Ensures(Contract.Result<Boogie2VCExprTranslator>() != null);
throw new NotImplementedException(); }
}
public override VCGenerationOptions VCGenOptions
{
get {Contract.Ensures(Contract.Result<VCGenerationOptions>() != null);
throw new NotImplementedException(); }
}
public override object Clone()
{
Contract.Ensures(Contract.Result<object>() != null);
throw new NotImplementedException();
}
}
// -----------------------------------------------------------------------------------------------
// -----------------------------------------------------------------------------------------------
// -----------------------------------------------------------------------------------------------
/// <summary>
/// This ProverContext subclass is intended for use with untyped provers that do not require names
/// to be declared before use. It constructs its context from unique constants and given axioms.
/// </summary>
public class DeclFreeProverContext : ProverContext {
protected VCExpressionGenerator gen;
protected VCGenerationOptions genOptions;
protected Boogie2VCExprTranslator translator;
protected OrderingAxiomBuilder orderingAxiomBuilder;
protected List<Variable> distincts;
protected List<VCExpr> axiomConjuncts;
[ContractInvariantMethod]
void ObjectInvariant() {
Contract.Invariant(gen != null);
Contract.Invariant(genOptions != null);
Contract.Invariant(translator != null);
Contract.Invariant(orderingAxiomBuilder != null);
Contract.Invariant(cce.NonNullElements(distincts));
Contract.Invariant(cce.NonNullElements(axiomConjuncts));
}
public VCExprTranslator/*?*/ exprTranslator;
public DeclFreeProverContext(VCExpressionGenerator gen,
VCGenerationOptions genOptions) {
Contract.Requires(gen != null);
Contract.Requires(genOptions != null);
this.gen = gen;
this.genOptions = genOptions;
Boogie2VCExprTranslator t = new Boogie2VCExprTranslator (gen, genOptions);
this.translator = t;
OrderingAxiomBuilder oab = new OrderingAxiomBuilder(gen, t);
Contract.Assert(oab != null);
oab.Setup();
this.orderingAxiomBuilder = oab;
distincts = new List<Variable>();
axiomConjuncts = new List<VCExpr>();
exprTranslator = null;
}
protected DeclFreeProverContext(DeclFreeProverContext ctxt) {
Contract.Requires(ctxt != null);
this.gen = ctxt.gen;
this.genOptions = ctxt.genOptions;
Boogie2VCExprTranslator t = (Boogie2VCExprTranslator)ctxt.translator.Clone();
Contract.Assert(t != null);
this.translator = t;
this.orderingAxiomBuilder = new OrderingAxiomBuilder(ctxt.gen, t, ctxt.orderingAxiomBuilder);
StringBuilder cmds = new StringBuilder ();
distincts = new List<Variable>(ctxt.distincts);
axiomConjuncts = new List<VCExpr>(ctxt.axiomConjuncts);
if (ctxt.exprTranslator == null)
exprTranslator = null;
else
exprTranslator = (VCExprTranslator)cce.NonNull(ctxt.exprTranslator.Clone());
}
public override object Clone() {
Contract.Ensures(Contract.Result<object>() != null);
return new DeclFreeProverContext(this);
}
public override void DeclareFunction(Function f, string attributes) {//Contract.Requires(f != null);
base.ProcessDeclaration(f);
}
public override void DeclareConstant(Constant c, bool uniq, string attributes) {//Contract.Requires(c != null);
base.DeclareConstant(c, uniq, attributes);
orderingAxiomBuilder.AddConstant(c);
// TODO: make separate distinct lists for names coming from different types
// e.g., one for strings, one for ints, one for program types.
if (uniq){
distincts.Add(c);
}
}
public override void AddAxiom(Axiom ax, string attributes) {//Contract.Requires(ax != null);
base.AddAxiom(ax, attributes);
axiomConjuncts.Add(translator.Translate(ax.Expr));
}
public override void AddAxiom(VCExpr vc)
{//Contract.Requires(vc != null);
axiomConjuncts.Add(vc);
}
public VCExpr Axioms {
get {Contract.Ensures(Contract.Result<VCExpr>() != null);
VCExpr axioms = gen.NAry(VCExpressionGenerator.AndOp, axiomConjuncts);
List<VCExpr>/*!>!*/ distinctVars = new List<VCExpr> ();
foreach (Variable v in distincts){
Contract.Assert(v != null);
distinctVars.Add(translator.LookupVariable(v));}
axioms = gen.AndSimp(gen.Distinct(distinctVars), axioms);
if (CommandLineOptions.Clo.TypeEncodingMethod != CommandLineOptions.TypeEncoding.Monomorphic)
axioms = gen.AndSimp(orderingAxiomBuilder.Axioms, axioms);
return axioms;
}
}
public override string Lookup(VCExprVar var)
{
return exprTranslator.Lookup(var);
}
public override VCExpressionGenerator ExprGen { get {Contract.Ensures(Contract.Result<VCExpressionGenerator>() != null);
return gen;
} }
public override Boogie2VCExprTranslator BoogieExprTranslator { get {Contract.Ensures(Contract.Result<Boogie2VCExprTranslator>() != null);
return translator;
} }
public override VCGenerationOptions VCGenOptions { get {Contract.Ensures(Contract.Result<VCGenerationOptions>() != null);
return genOptions;
} }
}
// Translator from VCExpressions to strings, which are implemented
// by the various provers
[ContractClass(typeof(VCExprTranslatorContracts))]
public abstract class VCExprTranslator : ICloneable {
public abstract string translate(VCExpr expr, int polarity);
public abstract string Lookup(VCExprVar var);
public abstract Object Clone();
}
[ContractClassFor(typeof(VCExprTranslator))]
public abstract class VCExprTranslatorContracts : VCExprTranslator {
public override object Clone() {
Contract.Ensures(Contract.Result<object>() != null);
throw new NotImplementedException();
}
public override string Lookup(VCExprVar var) {
Contract.Requires(var != null);
Contract.Ensures(Contract.Result<string>() != null);
throw new NotImplementedException();
}
public override string translate(VCExpr expr, int polarity) {
Contract.Requires(expr != null);
Contract.Ensures(Contract.Result<string>() != null);
throw new NotImplementedException();
}
}
}
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