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|
//-----------------------------------------------------------------------------
//
// Copyright (C) Microsoft Corporation. All Rights Reserved.
//
//-----------------------------------------------------------------------------
using System;
using System.Text;
using System.IO;
using System.Collections;
using System.Collections.Generic;
using System.Diagnostics.Contracts;
using Microsoft.Basetypes;
// A translator from the Boogie AST to the VCExpr AST.
// This was previously realised in the methods AbsyExpr.VCView
namespace Microsoft.Boogie.VCExprAST {
using Microsoft.Boogie;
// TODO: in future we might use that for defining symbols for Boogie's conditional compilation
public class VCGenerationOptions {
private readonly List<string/*!*/>/*!*/ SupportedProverCommands;
[ContractInvariantMethod]
void ObjectInvariant() {
Contract.Invariant(cce.NonNullElements(SupportedProverCommands));
}
public bool IsProverCommandSupported(string kind) {
Contract.Requires(kind != null);
return SupportedProverCommands.Contains(kind);
}
public bool IsAnyProverCommandSupported(string kinds) {
Contract.Requires(kinds != null);
if (kinds.IndexOf(',') < 0) {
return IsProverCommandSupported(kinds);
} else {
return Contract.Exists(kinds.Split(',', ' '), k => IsProverCommandSupported(k));
}
}
public VCGenerationOptions(List<string/*!*/>/*!*/ supportedProverCommands) {
Contract.Requires(cce.NonNullElements(supportedProverCommands));
this.SupportedProverCommands = supportedProverCommands;
}
}
public delegate VCExpr/*!*/ CodeExprConverter(CodeExpr/*!*/ codeExpr, Hashtable/*<Block, VCExprVar!>*//*!*/ blockVariables, List<VCExprLetBinding> bindings);
public class Boogie2VCExprTranslator : StandardVisitor, ICloneable {
// Stack on which the various Visit-methods put the result of the translation
private readonly Stack<VCExpr/*!*/>/*!*/ SubExpressions = new Stack<VCExpr>();
[ContractInvariantMethod]
void ObjectInvariant() {
Contract.Invariant(cce.NonNullElements(SubExpressions));
Contract.Invariant(Gen != null);
}
private void Push(VCExpr expr) {
Contract.Requires(expr != null);
SubExpressions.Push(expr);
}
private VCExpr Pop() {
Contract.Ensures(Contract.Result<VCExpr>() != null);
return SubExpressions.Pop();
}
public VCExpr Translate(Expr expr) {
Contract.Requires(expr != null);
Contract.Ensures(Contract.Result<VCExpr>() != null);
this.Visit(expr);
return Pop();
}
public List<VCExpr/*!*/>/*!*/ Translate(ExprSeq exprs) {
Contract.Requires(exprs != null);
Contract.Ensures(cce.NonNullElements(Contract.Result<List<VCExpr>>()));
List<VCExpr/*!*/>/*!*/ res = new List<VCExpr/*!*/>();
foreach (Expr e in exprs)
res.Add(Translate(cce.NonNull(e)));
return res;
}
///////////////////////////////////////////////////////////////////////////////
internal readonly VCExpressionGenerator/*!*/ Gen;
public Boogie2VCExprTranslator(VCExpressionGenerator gen,
VCGenerationOptions genOptions) {
Contract.Requires(gen != null);
Contract.Requires(genOptions != null);
this.Gen = gen;
this.GenerationOptions = genOptions;
UnboundVariables = new VariableMapping<Variable>();
BoundVariables = new VariableMapping<BoundVariable>();
Formals = new VariableMapping<Formal>();
}
private Boogie2VCExprTranslator(Boogie2VCExprTranslator tl) {
Contract.Requires(tl != null);
this.Gen = tl.Gen;
this.GenerationOptions = tl.GenerationOptions;
UnboundVariables =
(VariableMapping<Variable>)tl.UnboundVariables.Clone();
BoundVariables = new VariableMapping<BoundVariable>();
Formals = new VariableMapping<Formal>();
}
public object Clone() {
Contract.Ensures(Contract.Result<object>() != null);
return new Boogie2VCExprTranslator(this);
}
private IAppliableTranslator IAppTranslatorAttr = null;
private IAppliableTranslator IAppTranslator {
get {
Contract.Ensures(Contract.Result<IAppliableTranslator>() != null);
if (IAppTranslatorAttr == null)
IAppTranslatorAttr = new IAppliableTranslator(this);
return IAppTranslatorAttr;
}
}
///////////////////////////////////////////////////////////////////////////////
// Class for handling occurring variables
private class VariableMapping<VarKind> : ICloneable {
private readonly List<Dictionary<VarKind/*!*/, VCExprVar/*!*/>/*!*/>/*!*/ Mapping;
[ContractInvariantMethod]
void ObjectInvariant() {
Contract.Invariant(Mapping != null && Contract.ForAll(Mapping, i => cce.NonNullDictionaryAndValues(i)));
}
public VariableMapping() {
List<Dictionary<VarKind/*!*/, VCExprVar/*!*/>/*!*/>/*!*/ mapping =
new List<Dictionary<VarKind/*!*/, VCExprVar/*!*/>/*!*/>();
mapping.Add(new Dictionary<VarKind/*!*/, VCExprVar/*!*/>());
this.Mapping = mapping;
}
private VariableMapping(VariableMapping<VarKind> vm) {
Contract.Requires(vm != null);
List<Dictionary<VarKind/*!*/, VCExprVar/*!*/>/*!*/>/*!*/ mapping =
new List<Dictionary<VarKind/*!*/, VCExprVar/*!*/>/*!*/>();
foreach (Dictionary<VarKind/*!*/, VCExprVar/*!*/>/*!*/ d in vm.Mapping) {
Contract.Assert(cce.NonNullDictionaryAndValues(d));
mapping.Add(new Dictionary<VarKind/*!*/, VCExprVar/*!*/>(d));
}
this.Mapping = mapping;
}
public object Clone() {
Contract.Ensures(Contract.Result<object>() != null);
return new VariableMapping<VarKind>(this);
}
public void PushScope() {
Mapping.Add(new Dictionary<VarKind/*!*/, VCExprVar/*!*/>());
}
public void PopScope() {
Contract.Assume(Mapping.Count > 0);
Mapping.RemoveAt(Mapping.Count - 1);
}
public void Bind(VarKind boogieVar, VCExprVar/*!*/ vcExprVar) {
Contract.Requires(vcExprVar != null);
Contract.Requires(boogieVar != null);
Contract.Requires(!Contains(boogieVar));
Mapping[Mapping.Count - 1].Add(boogieVar, vcExprVar);
}
public VCExprVar Lookup(VarKind boogieVar) {
Contract.Requires(boogieVar != null);
Contract.Ensures(Contract.Result<VCExprVar>() != null);
VCExprVar res = LookupHelp(boogieVar);
Contract.Assume(res != null);
return res;
}
[Pure]
public bool Contains(VarKind boogieVar) {
Contract.Requires(boogieVar != null);
return LookupHelp(boogieVar) != null;
}
public bool TryGetValue(VarKind boogieVar, out VCExprVar res) {
Contract.Requires(boogieVar != null);
res = LookupHelp(boogieVar);
return res != null;
}
[Pure]
private VCExprVar LookupHelp(VarKind boogieVar) {
Contract.Requires(boogieVar != null);
VCExprVar res;
foreach (Dictionary<VarKind/*!*/, VCExprVar/*!*/>/*!*/ d in Mapping) {
//Contract.Assert(cce.NonNullElements(d));
if (d.TryGetValue(boogieVar, out res)) {
Contract.Assert(res != null);
return res;
}
}
return null;
}
}
//////////////////////////////////////////////////////////////////////////////////
private readonly VariableMapping<Variable>/*!*/ UnboundVariables;
private readonly VariableMapping<BoundVariable>/*!*/ BoundVariables;
// used when translating the bodies of function expansions
private readonly VariableMapping<Formal>/*!*/ Formals;
[ContractInvariantMethod]
void ObjectInvairant() {
Contract.Invariant(UnboundVariables != null);
Contract.Invariant(BoundVariables != null);
Contract.Invariant(Formals != null);
}
internal void PushBoundVariableScope() {
BoundVariables.PushScope();
}
internal void PopBoundVariableScope() {
BoundVariables.PopScope();
}
internal void PushFormalsScope() {
Formals.PushScope();
}
internal void PopFormalsScope() {
Formals.PopScope();
}
public VCExprVar BindVariable(Variable boogieVar) {
Contract.Requires(boogieVar != null);
Contract.Ensures(Contract.Result<VCExprVar>() != null);
if (boogieVar is BoundVariable) {
VCExprVar/*!*/ newVar = Gen.Variable(boogieVar.Name, boogieVar.TypedIdent.Type);
BoundVariables.Bind((BoundVariable)boogieVar, newVar);
return newVar;
} else if (boogieVar is Formal) {
VCExprVar/*!*/ newVar = Gen.Variable(boogieVar.Name, boogieVar.TypedIdent.Type);
Formals.Bind((Formal)boogieVar, newVar);
return newVar;
} else {
// only bound variables and formals are declared explicitly
Contract.Assert(false);
throw new cce.UnreachableException();
}
}
public VCExprVar LookupVariable(Variable boogieVar) {
Contract.Requires(boogieVar != null);
Contract.Ensures(Contract.Result<VCExprVar>() != null);
BoundVariable bv = boogieVar as BoundVariable;
if (bv != null) {
return BoundVariables.Lookup(bv);
}
VCExprVar res;
Formal fml = boogieVar as Formal;
if (fml != null && Formals.TryGetValue(fml, out res))
return cce.NonNull(res);
// global variables, local variables, incarnations, etc. are
// bound the first time they occur
if (!UnboundVariables.TryGetValue(boogieVar, out res)) {
res = new VCExprVar(boogieVar.Name, boogieVar.TypedIdent.Type);
UnboundVariables.Bind(boogieVar, res);
}
return cce.NonNull(res);
}
/// <summary>
/// Unlike LookupVariable, this method does not create a new variable mapping if none is
/// found. Instead, this method returns null in such cases. Also, this method does not
/// look for bound variables.
/// </summary>
/// <param name="boogieVar"></param>
/// <returns></returns>
public VCExprVar TryLookupVariable(Variable boogieVar) {
Contract.Requires(boogieVar != null);
VCExprVar res;
Formal fml = boogieVar as Formal;
if (fml != null && Formals.TryGetValue(fml, out res))
return cce.NonNull(res);
if (UnboundVariables.TryGetValue(boogieVar, out res)) {
return cce.NonNull(res);
}
return null; // not present
}
///////////////////////////////////////////////////////////////////////////////////
internal readonly VCGenerationOptions/*!*/ GenerationOptions;
[ContractInvariantMethod]
void ObjectInvarian() {
Contract.Invariant(GenerationOptions != null);
}
///////////////////////////////////////////////////////////////////////////////////
public override LiteralExpr VisitLiteralExpr(LiteralExpr node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<LiteralExpr>() != null);
Push(TranslateLiteralExpr(node));
return node;
}
private VCExpr TranslateLiteralExpr(LiteralExpr node) {
Contract.Requires(node != null);
Contract.Ensures(Contract.Result<VCExpr>() != null);
if (node.Val is bool) {
bool b = (bool)node.Val;
if (b) {
return VCExpressionGenerator.True;
} else {
return VCExpressionGenerator.False;
}
} else if (node.Val is BigNum) {
return Gen.Integer(node.asBigNum);
} else if (node.Val is BvConst) {
return Gen.Bitvector((BvConst)node.Val);
} else {
System.Diagnostics.Debug.Assert(false, "unknown kind of literal " + node.tok.ToString());
Contract.Assert(false);
throw new cce.UnreachableException();
}
}
///////////////////////////////////////////////////////////////////////////////////
public override AIVariableExpr VisitAIVariableExpr(AIVariableExpr node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<AIVariableExpr>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
///////////////////////////////////////////////////////////////////////////////////
public override Expr VisitIdentifierExpr(IdentifierExpr node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Expr>() != null);
Contract.Assume(node.Decl != null); // the expression has to be resolved
Push(LookupVariable(node.Decl));
return node;
}
///////////////////////////////////////////////////////////////////////////////////
// Because of our scheme for numbering incarnations of variables, the pre-state
// value of a variable x is always just "x". (The first update to it in a method
// causes it to become "x0". So we just remove old expressions with a visitor
// before transforming it into a VCExpr.
public override Expr VisitOldExpr(OldExpr node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Expr>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
///////////////////////////////////////////////////////////////////////////////////
public override Expr VisitNAryExpr(NAryExpr node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Expr>() != null);
Push(TranslateNAryExpr(node));
return node;
}
private VCExpr TranslateNAryExpr(NAryExpr node) {
Contract.Requires(node != null);
Contract.Ensures(Contract.Result<VCExpr>() != null);
int n = node.Args.Length;
List<VCExpr/*!*/>/*!*/ vcs = new List<VCExpr/*!*/>(n);
for (int i = 0; i < n; i++) {
vcs.Add(Translate(cce.NonNull(node.Args)[i]));
}
if (node.Type == null) {
System.Console.WriteLine("*** type is null for {0}", node);
Contract.Assert(false);
throw new cce.UnreachableException();
}
return IAppTranslator.Translate(node.Fun, node.Type, vcs,
ToList(cce.NonNull(node.TypeParameters)));
}
private static List<Type/*!*/>/*!*/ EMPTY_TYPE_LIST = new List<Type/*!*/>();
[ContractInvariantMethod]
void ObjectInvirant() {
Contract.Invariant(EMPTY_TYPE_LIST != null);
}
private List<Type/*!*/>/*!*/ ToList(TypeParamInstantiation insts) {
Contract.Requires(insts != null);
Contract.Ensures(cce.NonNullElements(Contract.Result<List<Type>>()));
if (insts.FormalTypeParams.Count == 0)
return EMPTY_TYPE_LIST;
List<Type/*!*/>/*!*/ typeArgs = new List<Type/*!*/>();
foreach (TypeVariable/*!*/ var in insts.FormalTypeParams) {
Contract.Assert(var != null);
typeArgs.Add(insts[var]);
}
return typeArgs;
}
///////////////////////////////////////////////////////////////////////////////////
public override QuantifierExpr VisitQuantifierExpr(QuantifierExpr node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<QuantifierExpr>() != null);
Push(TranslateQuantifierExpr(node));
return node;
}
public override ExistsExpr VisitExistsExpr(ExistsExpr node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<ExistsExpr>() != null);
node = (ExistsExpr)this.VisitQuantifierExpr(node);
return node;
}
public override ForallExpr VisitForallExpr(ForallExpr node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<ForallExpr>() != null);
node = (ForallExpr)this.VisitQuantifierExpr(node);
return node;
}
private VCExpr TranslateQuantifierExpr(QuantifierExpr node) {
Contract.Requires(node != null);
Contract.Ensures(Contract.Result<VCExpr>() != null);
List<TypeVariable/*!*/>/*!*/ typeParams = new List<TypeVariable/*!*/>();
foreach (TypeVariable/*!*/ v in node.TypeParameters) {
Contract.Assert(v != null);
typeParams.Add(v);
}
PushBoundVariableScope();
List<VCExprVar/*!*/>/*!*/ boundVars = new List<VCExprVar/*!*/>();
foreach (Variable/*!*/ v in node.Dummies)
boundVars.Add(BindVariable(v));
try {
List<VCTrigger/*!*/>/*!*/ triggers = TranslateTriggers(node.Triggers);
VCExpr/*!*/ body = Translate(node.Body);
VCQuantifierInfos/*!*/ infos = GenerateQuantifierInfos(node);
Quantifier quan;
if (node is ForallExpr)
quan = Quantifier.ALL;
else if (node is ExistsExpr)
quan = Quantifier.EX;
else {
Contract.Assert(false);
throw new cce.UnreachableException();
}
return Gen.Quantify(quan, typeParams, boundVars, triggers, infos, body);
} finally {
PopBoundVariableScope();
}
}
private List<VCTrigger/*!*/>/*!*/ TranslateTriggers(Trigger node) {
Contract.Ensures(cce.NonNullElements(Contract.Result<List<VCTrigger>>()));
List<VCTrigger/*!*/>/*!*/ res = new List<VCTrigger/*!*/>();
Trigger curTrigger = node;
while (curTrigger != null) {
res.Add(Gen.Trigger(curTrigger.Pos, Translate(curTrigger.Tr)));
curTrigger = curTrigger.Next;
}
return res;
}
private VCQuantifierInfos GenerateQuantifierInfos(QuantifierExpr node) {
Contract.Requires(node != null);
Contract.Ensures(Contract.Result<VCQuantifierInfos>() != null);
string qid = getQidNameFromQKeyValue(node.Dummies, node.Attributes);
return new VCQuantifierInfos(qid, node.SkolemId, false, node.Attributes);
}
private string getQidNameFromQKeyValue(VariableSeq vars, QKeyValue attributes) {
Contract.Requires(vars != null);
// Check for a 'qid, name' pair in keyvalues
string qid = QKeyValue.FindStringAttribute(attributes, "qid");
if (qid == null && vars.Length != 0) {
// generate default name (line:column position in .bpl file)
Variable v = vars[0];
Contract.Assert(v != null); // Rustan's claim!
// Include the first 8 characters of the filename in QID (helpful in case we use /concat)
// We limit it to 8, so the SX file doesn't grow too big, and who on earth would need
// more than 8 characters in a filename anyways.
int max = 8;
StringBuilder buf = new StringBuilder(max + 20);
string filename = v.tok.filename;
if (filename == null)
filename = "unknown";
for (int i = 0; i < filename.Length; ++i) {
if (filename[i] == '/' || filename[i] == '\\')
buf.Length = 0;
if (buf.Length < max && char.IsLetterOrDigit(filename[i])) {
if (buf.Length == 0 && char.IsDigit(filename[i])) {
// Z3 does not like QID's to start with a digit, so we prepend another character
buf.Append('_');
}
buf.Append(filename[i]);
}
}
buf.Append('.').Append(v.Line).Append(':').Append(v.Col);
qid = buf.ToString();
}
return qid;
}
///////////////////////////////////////////////////////////////////////////////////
public override BvExtractExpr VisitBvExtractExpr(BvExtractExpr node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<BvExtractExpr>() != null);
Push(TranslateBvExtractExpr(node));
return node;
}
private VCExpr TranslateBvExtractExpr(BvExtractExpr node) {
Contract.Requires(node != null);
Contract.Requires((node.Start <= node.End));
Contract.Ensures(Contract.Result<VCExpr>() != null);
VCExpr/*!*/ bv = Translate(node.Bitvector);
return Gen.BvExtract(bv, cce.NonNull(node.Bitvector.Type).BvBits, node.Start, node.End);
}
///////////////////////////////////////////////////////////////////////////////////
public override BvConcatExpr VisitBvConcatExpr(BvConcatExpr node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<BvConcatExpr>() != null);
Push(TranslateBvConcatExpr(node));
return node;
}
private VCExpr TranslateBvConcatExpr(BvConcatExpr node) {
Contract.Requires(node != null);
Contract.Ensures(Contract.Result<VCExpr>() != null);
VCExpr/*!*/ bv0 = Translate(node.E0);
VCExpr/*!*/ bv1 = Translate(node.E1);
return Gen.BvConcat(bv0, bv1);
}
///////////////////////////////////////////////////////////////////////////////////
// all the other cases should never happen
public override Cmd VisitAssertCmd(AssertCmd node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Cmd>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Cmd VisitAssignCmd(AssignCmd node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Cmd>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Cmd VisitAssumeCmd(AssumeCmd node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Cmd>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override AtomicRE VisitAtomicRE(AtomicRE node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<AtomicRE>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Axiom VisitAxiom(Axiom node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Axiom>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Type VisitBasicType(BasicType node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Type>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Type VisitBvType(BvType node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Type>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Block VisitBlock(Block node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Block>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
CodeExprConverter codeExprConverter = null;
public void SetCodeExprConverter(CodeExprConverter f) {
this.codeExprConverter = f;
}
public override Expr/*!*/ VisitCodeExpr(CodeExpr/*!*/ codeExpr) {
//Contract.Requires(codeExpr != null);
Contract.Ensures(Contract.Result<Expr>() != null);
Contract.Assume(codeExprConverter != null);
Hashtable/*<Block, LetVariable!>*/ blockVariables = new Hashtable/*<Block, LetVariable!!>*/();
List<VCExprLetBinding/*!*/> bindings = new List<VCExprLetBinding/*!*/>();
VCExpr e = codeExprConverter(codeExpr, blockVariables, bindings);
Push(e);
return codeExpr;
}
public override BlockSeq VisitBlockSeq(BlockSeq blockSeq) {
//Contract.Requires(blockSeq != null);
Contract.Ensures(Contract.Result<BlockSeq>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override List<Block/*!*/>/*!*/ VisitBlockList(List<Block/*!*/>/*!*/ blocks) {
//Contract.Requires(cce.NonNullElements(blocks));
Contract.Ensures(cce.NonNullElements(Contract.Result<List<Block>>()));
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override BoundVariable VisitBoundVariable(BoundVariable node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<BoundVariable>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Cmd VisitCallCmd(CallCmd node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Cmd>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Cmd VisitCallForallCmd(CallForallCmd node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Cmd>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override CmdSeq VisitCmdSeq(CmdSeq cmdSeq) {
//Contract.Requires(cmdSeq != null);
Contract.Ensures(Contract.Result<CmdSeq>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Choice VisitChoice(Choice node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Choice>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Cmd VisitCommentCmd(CommentCmd node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Cmd>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Constant VisitConstant(Constant node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Constant>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override CtorType VisitCtorType(CtorType node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<CtorType>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Declaration VisitDeclaration(Declaration node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Declaration>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override List<Declaration/*!*/>/*!*/ VisitDeclarationList(List<Declaration/*!*/>/*!*/ declarationList) {
//Contract.Requires(cce.NonNullElements(declarationList));
Contract.Ensures(cce.NonNullElements(Contract.Result<List<Declaration>>()));
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override DeclWithFormals VisitDeclWithFormals(DeclWithFormals node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<DeclWithFormals>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Requires VisitRequires(Requires @requires) {
//Contract.Requires(@requires != null);
Contract.Ensures(Contract.Result<Requires>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override RequiresSeq VisitRequiresSeq(RequiresSeq requiresSeq) {
//Contract.Requires(requiresSeq != null);
Contract.Ensures(Contract.Result<RequiresSeq>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Ensures VisitEnsures(Ensures @ensures) {
//Contract.Requires(@ensures != null);
Contract.Ensures(Contract.Result<Ensures>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override EnsuresSeq VisitEnsuresSeq(EnsuresSeq ensuresSeq) {
//Contract.Requires(ensuresSeq != null);
Contract.Ensures(Contract.Result<EnsuresSeq>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Formal VisitFormal(Formal node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Formal>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Function VisitFunction(Function node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Function>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override GlobalVariable VisitGlobalVariable(GlobalVariable node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<GlobalVariable>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override GotoCmd VisitGotoCmd(GotoCmd node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<GotoCmd>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Cmd VisitHavocCmd(HavocCmd node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Cmd>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Implementation VisitImplementation(Implementation node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Implementation>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override LocalVariable VisitLocalVariable(LocalVariable node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<LocalVariable>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override AssignLhs VisitMapAssignLhs(MapAssignLhs node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<AssignLhs>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override MapType VisitMapType(MapType node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<MapType>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Procedure VisitProcedure(Procedure node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Procedure>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Program VisitProgram(Program node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Program>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Cmd VisitRE(RE node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Cmd>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override RESeq VisitRESeq(RESeq reSeq) {
//Contract.Requires(reSeq != null);
Contract.Ensures(Contract.Result<RESeq>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override ReturnCmd VisitReturnCmd(ReturnCmd node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<ReturnCmd>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override ReturnExprCmd VisitReturnExprCmd(ReturnExprCmd node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<ReturnExprCmd>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Sequential VisitSequential(Sequential node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Sequential>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override AssignLhs VisitSimpleAssignLhs(SimpleAssignLhs node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<AssignLhs>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Cmd VisitStateCmd(StateCmd node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Cmd>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override TransferCmd VisitTransferCmd(TransferCmd node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<TransferCmd>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Trigger VisitTrigger(Trigger node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Trigger>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Type VisitType(Type node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Type>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override TypedIdent VisitTypedIdent(TypedIdent node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<TypedIdent>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Type VisitTypeSynonymAnnotation(TypeSynonymAnnotation node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Type>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Type VisitTypeVariable(TypeVariable node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Type>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Variable VisitVariable(Variable node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Variable>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override VariableSeq VisitVariableSeq(VariableSeq variableSeq) {
//Contract.Requires(variableSeq != null);
Contract.Ensures(Contract.Result<VariableSeq>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Cmd VisitAssertEnsuresCmd(AssertEnsuresCmd node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Cmd>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
public override Cmd VisitAssertRequiresCmd(AssertRequiresCmd node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Cmd>() != null);
Contract.Assert(false);
throw new cce.UnreachableException();
}
}
/////////////////////////////////////////////////////////////////////////////////
public class IAppliableTranslator : IAppliableVisitor<VCExpr/*!*/> {
private readonly Boogie2VCExprTranslator/*!*/ BaseTranslator;
[ContractInvariantMethod]
void ObjectInvariant() {
Contract.Invariant(BaseTranslator != null);
}
private VCExpressionGenerator/*!*/ Gen {
get {
Contract.Ensures(Contract.Result<VCExpressionGenerator>() != null);
return BaseTranslator.Gen;
}
}
private VCGenerationOptions GenerationOptions {
get {
Contract.Ensures(Contract.Result<VCGenerationOptions>() != null);
return BaseTranslator.GenerationOptions;
}
}
public IAppliableTranslator(Boogie2VCExprTranslator baseTranslator) {
Contract.Requires(baseTranslator != null);
this.BaseTranslator = baseTranslator;
}
///////////////////////////////////////////////////////////////////////////////
private List<VCExpr/*!*/>/*!*/ args = new List<VCExpr/*!*/>();
private List<Type/*!*/>/*!*/ typeArgs = new List<Type/*!*/>();
[ContractInvariantMethod]
void ObjectInvarianet() {
Contract.Invariant(args != null);
Contract.Invariant(typeArgs != null);
}
public VCExpr Translate(IAppliable app, Type ty, List<VCExpr/*!*/>/*!*/ args, List<Type/*!*/>/*!*/ typeArgs) {
Contract.Requires(ty != null);
Contract.Requires(app != null);
Contract.Requires(cce.NonNullElements(typeArgs));
Contract.Requires(cce.NonNullElements(args));
Contract.Ensures(Contract.Result<VCExpr>() != null);
List<VCExpr/*!*/>/*!*/ oldArgs = this.args;
List<Type/*!*/>/*!*/ oldTypeArgs = this.typeArgs;
this.args = args;
this.typeArgs = typeArgs;
VCExpr/*!*/ result = app.Dispatch<VCExpr/*!*/>(this);
this.args = oldArgs;
this.typeArgs = oldTypeArgs;
return result;
}
///////////////////////////////////////////////////////////////////////////////
public VCExpr Visit(UnaryOperator unaryOperator) {
//Contract.Requires(unaryOperator != null);
Contract.Ensures(Contract.Result<VCExpr>() != null);
Contract.Assert(unaryOperator.Op == UnaryOperator.Opcode.Not && this.args.Count == 1);
return Gen.Not(this.args);
}
public VCExpr Visit(BinaryOperator binaryOperator) {
//Contract.Requires(binaryOperator != null);
Contract.Ensures(Contract.Result<VCExpr>() != null);
return TranslateBinaryOperator(binaryOperator, this.args);
}
public VCExpr Visit(FunctionCall functionCall) {
//Contract.Requires(functionCall != null);
Contract.Ensures(Contract.Result<VCExpr>() != null);
return TranslateFunctionCall(functionCall, this.args, this.typeArgs);
}
public VCExpr Visit(MapSelect mapSelect) {
//Contract.Requires(mapSelect != null);
Contract.Ensures(Contract.Result<VCExpr>() != null);
return Gen.Select(this.args, this.typeArgs);
}
public VCExpr Visit(MapStore mapStore) {
//Contract.Requires(mapStore != null);
Contract.Ensures(Contract.Result<VCExpr>() != null);
return Gen.Store(this.args, this.typeArgs);
}
public VCExpr Visit(TypeCoercion typeCoercion) {
//Contract.Requires(typeCoercion != null);
Contract.Ensures(Contract.Result<VCExpr>() != null);
Contract.Assert(this.args.Count == 1);
return this.args[0];
}
public VCExpr Visit(IfThenElse ite) {
//Contract.Requires(ite != null);
Contract.Ensures(Contract.Result<VCExpr>() != null);
return Gen.Function(VCExpressionGenerator.IfThenElseOp, this.args);
}
///////////////////////////////////////////////////////////////////////////////
private VCExpr TranslateBinaryOperator(BinaryOperator app, List<VCExpr/*!*/>/*!*/ args) {
Contract.Requires(app != null);
Contract.Requires(cce.NonNullElements(args));
Contract.Ensures(Contract.Result<VCExpr>() != null);
Contract.Assert(args.Count == 2);
switch (app.Op) {
case BinaryOperator.Opcode.Add:
return Gen.Function(VCExpressionGenerator.AddOp, args);
case BinaryOperator.Opcode.Sub:
return Gen.Function(VCExpressionGenerator.SubOp, args);
case BinaryOperator.Opcode.Mul:
return Gen.Function(VCExpressionGenerator.MulOp, args);
case BinaryOperator.Opcode.Div:
return Gen.Function(VCExpressionGenerator.DivOp, args);
case BinaryOperator.Opcode.Mod:
return Gen.Function(VCExpressionGenerator.ModOp, args);
case BinaryOperator.Opcode.Eq:
case BinaryOperator.Opcode.Iff:
// we don't distinguish between equality and equivalence at this point
return Gen.Function(VCExpressionGenerator.EqOp, args);
case BinaryOperator.Opcode.Neq:
return Gen.Function(VCExpressionGenerator.NeqOp, args);
case BinaryOperator.Opcode.Lt:
return Gen.Function(VCExpressionGenerator.LtOp, args);
case BinaryOperator.Opcode.Le:
return Gen.Function(VCExpressionGenerator.LeOp, args);
case BinaryOperator.Opcode.Ge:
return Gen.Function(VCExpressionGenerator.GeOp, args);
case BinaryOperator.Opcode.Gt:
return Gen.Function(VCExpressionGenerator.GtOp, args);
case BinaryOperator.Opcode.Imp:
return Gen.Function(VCExpressionGenerator.ImpliesOp, args);
case BinaryOperator.Opcode.And:
return Gen.Function(VCExpressionGenerator.AndOp, args);
case BinaryOperator.Opcode.Or:
return Gen.Function(VCExpressionGenerator.OrOp, args);
case BinaryOperator.Opcode.Subtype:
return Gen.Function(VCExpressionGenerator.SubtypeOp, args);
default:
Contract.Assert(false);
throw new cce.UnreachableException(); // unexpected binary operator
}
}
///////////////////////////////////////////////////////////////////////////////
private VCExpr/*!*/ TranslateFunctionCall(FunctionCall app, List<VCExpr/*!*/>/*!*/ args, List<Type/*!*/>/*!*/ typeArgs) {
Contract.Requires(cce.NonNullElements(args));
Contract.Requires(cce.NonNullElements(typeArgs));
Contract.Requires(app != null);
Contract.Requires((app.Func != null));
Contract.Ensures(Contract.Result<VCExpr>() != null); // resolution must have happened
VCExpr res = ApplyExpansion(app, args, typeArgs);
if (res != null)
return res;
VCExprOp/*!*/ functionOp = Gen.BoogieFunctionOp(app.Func);
return Gen.Function(functionOp, args, typeArgs);
}
private VCExpr ApplyExpansion(FunctionCall app, List<VCExpr/*!*/>/*!*/ args, List<Type/*!*/>/*!*/ typeArgs) {
Contract.Requires(app != null);
Contract.Requires(cce.NonNullElements(args));
Contract.Requires(cce.NonNullElements(typeArgs));
Contract.Assert(app.Func != null); // resolution must have happened
if (app.Func.doingExpansion) {
System.Console.WriteLine("*** detected expansion loop on {0}", app.Func);
return null;
}
Expansion exp = FindExpansion(app.Func);
if (exp == null)
return null;
VCExpr/*!*/ translatedBody;
VCExprSubstitution/*!*/ subst = new VCExprSubstitution();
try {
BaseTranslator.PushFormalsScope();
BaseTranslator.PushBoundVariableScope();
app.Func.doingExpansion = true;
// first bind the formals to VCExpr variables, which are later
// substituted with the actual parameters
for (int i = 0; i < exp.formals.Length; ++i)
subst[BaseTranslator.BindVariable(cce.NonNull(exp.formals)[i])] = args[i];
// recursively translate the body of the expansion
translatedBody = BaseTranslator.Translate(exp.body);
} finally {
BaseTranslator.PopFormalsScope();
BaseTranslator.PopBoundVariableScope();
app.Func.doingExpansion = false;
}
// substitute the formals with the actual parameters in the body
Contract.Assert(typeArgs.Count == exp.TypeParameters.Length);
for (int i = 0; i < typeArgs.Count; ++i)
subst[exp.TypeParameters[i]] = typeArgs[i];
SubstitutingVCExprVisitor/*!*/ substituter = new SubstitutingVCExprVisitor(Gen);
return substituter.Mutate(translatedBody, subst);
}
private Expansion FindExpansion(Function func) {
Contract.Requires(func != null);
if (func.expansions == null)
return null;
Expansion exp = null;
foreach (Expansion e in func.expansions) {
Contract.Assert(e != null);
if (e.ignore == null || !GenerationOptions.IsAnyProverCommandSupported(e.ignore)) {
if (exp == null) {
exp = e;
} else {
System.Console.WriteLine("*** more than one possible expansion for {0}", func);
return null;
}
}
}
return exp;
}
}
}
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