public virtual ExistsExpr VisitExistsExpr(ExistsExpr node)
{
Contract.Requires(node != null);
Contract.Ensures(Contract.Result <ExistsExpr>() != null);
node = (ExistsExpr)this.VisitQuantifierExpr(node);
return(node);
}
public Expr DisjointnessExpr(string domainName, HashSet <Variable> scope)
{
LinearDomain domain = linearDomains[domainName];
BoundVariable partition = new BoundVariable(Token.NoToken, new TypedIdent(Token.NoToken, string.Format("partition_{0}", domainName), new MapType(Token.NoToken, new List <TypeVariable>(), new List <Type> {
domain.elementType
}, Microsoft.Boogie.Type.Int)));
Expr disjointExpr = Expr.True;
int count = 0;
foreach (Variable v in scope)
{
IdentifierExpr ie = new IdentifierExpr(Token.NoToken, v);
Expr e = new NAryExpr(Token.NoToken, new FunctionCall(domain.mapConstInt), new List <Expr> {
new LiteralExpr(Token.NoToken, Microsoft.Basetypes.BigNum.FromInt(count++))
});
e = new NAryExpr(Token.NoToken, new FunctionCall(domain.mapEqInt), new List <Expr> {
new IdentifierExpr(Token.NoToken, partition), e
});
e = new NAryExpr(Token.NoToken, new FunctionCall(domain.mapImpBool), new List <Expr> {
v.TypedIdent.Type is MapType ? ie : Singleton(ie, domainName), e
});
e = Expr.Binary(BinaryOperator.Opcode.Eq, e, new NAryExpr(Token.NoToken, new FunctionCall(domain.mapConstBool), new List <Expr> {
Expr.True
}));
disjointExpr = Expr.Binary(BinaryOperator.Opcode.And, e, disjointExpr);
}
var expr = new ExistsExpr(Token.NoToken, new List <Variable> {
partition
}, disjointExpr);
expr.Resolve(new ResolutionContext(null));
expr.Typecheck(new TypecheckingContext(null));
return(expr);
}
private Expr CalculatePathCondition(PathInfo path)
{
Expr returnExpr = Expr.True;
HashSet <Variable> existsVars = path.existsVars;
Dictionary <Variable, Expr> existsMap = new Dictionary <Variable, Expr>();
Dictionary <Variable, Expr> varToExpr = path.varToExpr;
foreach (Variable v in varToExpr.Keys)
{
if (postExistVars.Contains(v))
{
continue;
}
IdentifierExpr ie = varToExpr[v] as IdentifierExpr;
if (ie != null && !existsMap.ContainsKey(ie.Decl) && existsVars.Contains(ie.Decl))
{
existsMap[ie.Decl] = Expr.Ident(v);
existsVars.Remove(ie.Decl);
}
else
{
returnExpr = Expr.And(returnExpr, Expr.Eq(Expr.Ident(v), (new MyDuplicator()).VisitExpr(varToExpr[v])));
returnExpr.Type = Type.Bool;
}
}
List <Expr> pathExprs = new List <Expr>();
path.pathExprs.ForEach(x => pathExprs.Add((new MyDuplicator()).VisitExpr(x)));
foreach (Expr x in pathExprs)
{
Variable boundVar;
Expr boundVarExpr;
if (InferSubstitution(x, out boundVar, out boundVarExpr) && existsVars.Contains(boundVar))
{
existsMap[boundVar] = boundVarExpr;
existsVars.Remove(boundVar);
}
else
{
returnExpr = Expr.And(returnExpr, x);
returnExpr.Type = Type.Bool;
}
}
returnExpr = Substituter.Apply(Substituter.SubstitutionFromHashtable(existsMap), returnExpr);
if (existsVars.Count > 0)
{
returnExpr = new ExistsExpr(Token.NoToken, new List <Variable>(existsVars), returnExpr);
}
return(returnExpr);
}
public Expr DisjointnessExprForPermissions(string domainName, IEnumerable<Expr> permissionsExprs)
{
Expr expr = Expr.True;
if (permissionsExprs.Count() > 1)
{
int count = 0;
List<Expr> subsetExprs = new List<Expr>();
LinearDomain domain = linearDomains[domainName];
BoundVariable partition = new BoundVariable(Token.NoToken,
new TypedIdent(Token.NoToken, $"partition_{domainName}", domain.mapTypeInt));
foreach (Expr e in permissionsExprs)
{
subsetExprs.Add(SubsetExpr(domain, e, partition, count));
count++;
}
expr = new ExistsExpr(Token.NoToken, new List<Variable> {partition}, Expr.And(subsetExprs));
}
expr.Resolve(new ResolutionContext(null));
expr.Typecheck(new TypecheckingContext(null));
return expr;
}
void PrintExistentialGuard(ExistsExpr guard) {
Contract.Requires(guard != null);
Contract.Requires(guard.Range == null);
PrintQuantifierDomain(guard.BoundVars, guard.Attributes, null);
wr.Write(" :| ");
PrintExpression(guard.Term, false);
}
public override QuantifierExpr VisitQuantifierExpr(QuantifierExpr node)
{
var oldE = existentialExpr;
if (node is ExistsExpr)
existentialExpr = (node as ExistsExpr);
node = base.VisitQuantifierExpr(node);
existentialExpr = oldE;
return node;
}
public FunctionCollector()
{
functionsUsed = new List<Tuple<Function, ExistsExpr>>();
existentialExpr = null;
}
public override ExistsExpr VisitExistsExpr(ExistsExpr node)
{
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result <ExistsExpr>() != null);
return(base.VisitExistsExpr((ExistsExpr)node.Clone()));
}
public void SimpleExists() {
var boundVar = new BoundVariable(Token.NoToken, new TypedIdent(Token.NoToken,"foo",Microsoft.Boogie.Type.Bool));
var id = new IdentifierExpr(Token.NoToken, boundVar);
var exists = new ExistsExpr(Token.NoToken, new List<Variable>() { boundVar }, id);
var id2 = new IdentifierExpr(Token.NoToken, boundVar);
var exists2 = new ExistsExpr(Token.NoToken, new List<Variable>() { boundVar }, id2);
Assert.AreNotSame(exists, exists2); // These are different references
Assert.IsTrue(exists.Equals(exists2)); // These are "structurally equal"
Assert.AreEqual(exists.GetHashCode(), exists2.GetHashCode()); // If the .Equals() is true then hash codes must be the same
}
protected override Cmd ComputeDesugaring()
{
Contract.Ensures(Contract.Result<Cmd>() != null);
List<Cmd> newBlockBody = new List<Cmd>();
Dictionary<Variable, Expr> substMap = new Dictionary<Variable, Expr>();
Dictionary<Variable, Expr> substMapOld = new Dictionary<Variable, Expr>();
Dictionary<Variable, Expr> substMapBound = new Dictionary<Variable, Expr>();
List<Variable>/*!*/ tempVars = new List<Variable>();
// proc P(ins) returns (outs)
// requires Pre
// //modifies frame
// ensures Post
//
// call aouts := P(ains)
// ins : formal in parameters of procedure
// frame : a list of global variables from the modifies clause
// outs : formal out parameters of procedure
// ains : actual in arguments passed to call
// aouts : actual variables assigned to from call
// cins : new variables created just for this call, one per ains
// cframe : new variables created just for this call, to keep track of OLD values
// couts : new variables created just for this call, one per aouts
// WildcardVars : new variables created just for this call, one per null in ains
#region Create cins; each one is an incarnation of the corresponding in parameter
List<Variable>/*!*/ cins = new List<Variable>();
List<Variable> wildcardVars = new List<Variable>();
Contract.Assume(this.Proc != null);
for (int i = 0; i < this.Proc.InParams.Count; ++i) {
Variable/*!*/ param = cce.NonNull(this.Proc.InParams[i]);
bool isWildcard = this.Ins[i] == null;
Type/*!*/ actualType;
if (isWildcard)
actualType = param.TypedIdent.Type.Substitute(TypeParamSubstitution());
else
// during type checking, we have ensured that the type of the actual
// parameter Ins[i] is correct, so we can use it here
actualType = cce.NonNull(cce.NonNull(Ins[i]).Type);
Variable cin = CreateTemporaryVariable(tempVars, param, actualType,
TempVarKind.Formal);
cins.Add(cin);
IdentifierExpr ie = new IdentifierExpr(cin.tok, cin);
substMap.Add(param, ie);
if (isWildcard) {
cin = CreateTemporaryVariable(tempVars, param,
actualType, TempVarKind.Bound);
wildcardVars.Add(cin);
ie = new IdentifierExpr(cin.tok, cin);
}
substMapBound.Add(param, ie);
}
#endregion
#region call aouts := P(ains) becomes: (open outlining one level to see)
#region cins := ains (or havoc cin when ain is null)
for (int i = 0, n = this.Ins.Count; i < n; i++) {
IdentifierExpr/*!*/ cin_exp = new IdentifierExpr(cce.NonNull(cins[i]).tok, cce.NonNull(cins[i]));
Contract.Assert(cin_exp != null);
if (this.Ins[i] != null) {
AssignCmd assign = Cmd.SimpleAssign(Token.NoToken, cin_exp, cce.NonNull(this.Ins[i]));
newBlockBody.Add(assign);
} else {
List<IdentifierExpr>/*!*/ ies = new List<IdentifierExpr>();
ies.Add(cin_exp);
HavocCmd havoc = new HavocCmd(Token.NoToken, ies);
newBlockBody.Add(havoc);
}
}
#endregion
#region assert (exists wildcardVars :: Pre[ins := cins])
Substitution s = Substituter.SubstitutionFromHashtable(substMapBound);
bool hasWildcard = (wildcardVars.Count != 0);
Expr preConjunction = null;
for (int i = 0; i < this.Proc.Requires.Count; i++) {
Requires/*!*/ req = cce.NonNull(this.Proc.Requires[i]);
if (!req.Free && !IsFree) {
if (hasWildcard) {
Expr pre = Substituter.Apply(s, req.Condition);
if (preConjunction == null) {
preConjunction = pre;
} else {
preConjunction = Expr.And(preConjunction, pre);
}
} else {
Requires/*!*/ reqCopy = (Requires/*!*/)cce.NonNull(req.Clone());
reqCopy.Condition = Substituter.Apply(s, req.Condition);
AssertCmd/*!*/ a = new AssertRequiresCmd(this, reqCopy);
Contract.Assert(a != null);
a.ErrorDataEnhanced = reqCopy.ErrorDataEnhanced;
newBlockBody.Add(a);
}
}
else if (CommandLineOptions.Clo.StratifiedInlining > 0)
{
// inject free requires as assume statements at the call site
AssumeCmd/*!*/ a = new AssumeCmd(req.tok, Substituter.Apply(s, req.Condition));
Contract.Assert(a != null);
newBlockBody.Add(a);
}
}
if (hasWildcard) {
if (preConjunction == null) {
preConjunction = Expr.True;
}
Expr/*!*/ expr = new ExistsExpr(tok, wildcardVars, preConjunction);
Contract.Assert(expr != null);
AssertCmd/*!*/ a = new AssertCmd(tok, expr);
Contract.Assert(a != null);
a.ErrorDataEnhanced = AssertCmd.GenerateBoundVarMiningStrategy(expr);
newBlockBody.Add(a);
}
#endregion
#region assume Pre[ins := cins] with formal paramters
if (hasWildcard) {
s = Substituter.SubstitutionFromHashtable(substMap);
for (int i = 0; i < this.Proc.Requires.Count; i++) {
Requires/*!*/ req = cce.NonNull(this.Proc.Requires[i]);
if (!req.Free) {
Requires/*!*/ reqCopy = (Requires/*!*/)cce.NonNull(req.Clone());
reqCopy.Condition = Substituter.Apply(s, req.Condition);
AssumeCmd/*!*/ a = new AssumeCmd(tok, reqCopy.Condition);
Contract.Assert(a != null);
newBlockBody.Add(a);
}
}
}
#endregion
#region cframe := frame (to hold onto frame values in case they are referred to in the postcondition)
List<IdentifierExpr> havocVarExprs = new List<IdentifierExpr>();
foreach (IdentifierExpr/*!*/ f in this.Proc.Modifies) {
Contract.Assert(f != null);
Contract.Assume(f.Decl != null);
Contract.Assert(f.Type != null);
Variable v = CreateTemporaryVariable(tempVars, f.Decl, f.Type, TempVarKind.Old);
IdentifierExpr v_exp = new IdentifierExpr(v.tok, v);
substMapOld.Add(f.Decl, v_exp); // this assumes no duplicates in this.Proc.Modifies
AssignCmd assign = Cmd.SimpleAssign(f.tok, v_exp, f);
newBlockBody.Add(assign);
// fra
if (!havocVarExprs.Contains(f))
havocVarExprs.Add(f);
}
#endregion
#region Create couts
List<Variable>/*!*/ couts = new List<Variable>();
for (int i = 0; i < this.Proc.OutParams.Count; ++i) {
Variable/*!*/ param = cce.NonNull(this.Proc.OutParams[i]);
bool isWildcard = this.Outs[i] == null;
Type/*!*/ actualType;
if (isWildcard)
actualType = param.TypedIdent.Type.Substitute(TypeParamSubstitution());
else
// during type checking, we have ensured that the type of the actual
// out parameter Outs[i] is correct, so we can use it here
actualType = cce.NonNull(cce.NonNull(Outs[i]).Type);
Variable cout = CreateTemporaryVariable(tempVars, param, actualType,
TempVarKind.Formal);
couts.Add(cout);
IdentifierExpr ie = new IdentifierExpr(cout.tok, cout);
substMap.Add(param, ie);
if (!havocVarExprs.Contains(ie))
havocVarExprs.Add(ie);
}
// add the where clauses, now that we have the entire substitution map
foreach (Variable/*!*/ param in this.Proc.OutParams) {
Contract.Assert(param != null);
Expr w = param.TypedIdent.WhereExpr;
if (w != null) {
IdentifierExpr ie = (IdentifierExpr/*!*/)cce.NonNull(substMap[param]);
Contract.Assert(ie.Decl != null);
ie.Decl.TypedIdent.WhereExpr = Substituter.Apply(Substituter.SubstitutionFromHashtable(substMap), w);
}
}
#endregion
#region havoc frame, couts
// pass on this's token
HavocCmd hc = new HavocCmd(this.tok, havocVarExprs);
newBlockBody.Add(hc);
#endregion
#region assume Post[ins, outs, old(frame) := cins, couts, cframe]
Substitution s2 = Substituter.SubstitutionFromHashtable(substMap);
Substitution s2old = Substituter.SubstitutionFromHashtable(substMapOld);
foreach (Ensures/*!*/ e in this.Proc.Ensures) {
Contract.Assert(e != null);
Expr copy = Substituter.ApplyReplacingOldExprs(s2, s2old, e.Condition);
AssumeCmd assume = new AssumeCmd(this.tok, copy);
#region stratified inlining support
if (QKeyValue.FindBoolAttribute(e.Attributes, "si_fcall"))
{
assume.Attributes = Attributes;
}
if (QKeyValue.FindBoolAttribute(e.Attributes, "candidate"))
{
assume.Attributes = new QKeyValue(Token.NoToken, "candidate", new List<object>(), assume.Attributes);
assume.Attributes.Params.Add(this.callee);
}
#endregion
newBlockBody.Add(assume);
}
#endregion
#region aouts := couts
for (int i = 0, n = this.Outs.Count; i < n; i++) {
if (this.Outs[i] != null) {
Variable/*!*/ param_i = cce.NonNull(this.Proc.OutParams[i]);
Expr/*!*/ cout_exp = new IdentifierExpr(cce.NonNull(couts[i]).tok, cce.NonNull(couts[i]));
Contract.Assert(cout_exp != null);
AssignCmd assign = Cmd.SimpleAssign(param_i.tok, cce.NonNull(this.Outs[i]), cout_exp);
newBlockBody.Add(assign);
}
}
#endregion
#endregion
return new StateCmd(this.tok, tempVars, newBlockBody);
}
void QuantifierGuts(out Expression q, bool allowSemi, bool allowLambda)
{
Contract.Ensures(Contract.ValueAtReturn(out q) != null); IToken/*!*/ x = Token.NoToken;
bool univ = false;
List<BoundVar/*!*/> bvars;
Attributes attrs;
Expression range;
Expression/*!*/ body;
if (la.kind == 103 || la.kind == 123) {
Forall();
x = t; univ = true;
} else if (la.kind == 124 || la.kind == 125) {
Exists();
x = t;
} else SynErr(238);
QuantifierDomain(out bvars, out attrs, out range);
QSep();
Expression(out body, allowSemi, allowLambda);
if (univ) {
q = new ForallExpr(x, bvars, range, body, attrs);
} else {
q = new ExistsExpr(x, bvars, range, body, attrs);
}
}
public override Expr VisitExistsExpr(ExistsExpr node)
{
Contract.Ensures(Contract.Result<Expr>() == node);
return (ExistsExpr)this.VisitQuantifierExpr(node);
}
private Expr CalculatePathCondition()
{
Expr returnExpr = Expr.True;
foreach (Variable v in program.GlobalVariables())
{
var eqExpr = Expr.Eq(new IdentifierExpr(Token.NoToken, v), new OldExpr(Token.NoToken, new IdentifierExpr(Token.NoToken, v)));
returnExpr = Expr.And(eqExpr, returnExpr);
}
if (first != null)
{
foreach (Variable v in first.thisOutParams)
{
var eqExpr = Expr.Eq(new IdentifierExpr(Token.NoToken, v), new OldExpr(Token.NoToken, new IdentifierExpr(Token.NoToken, v)));
returnExpr = Expr.And(eqExpr, returnExpr);
}
}
foreach (Variable v in second.thatOutParams)
{
var eqExpr = Expr.Eq(new IdentifierExpr(Token.NoToken, v), new OldExpr(Token.NoToken, new IdentifierExpr(Token.NoToken, v)));
returnExpr = Expr.And(eqExpr, returnExpr);
}
Block[] dfsStackAsArray = dfsStack.Reverse().ToArray();
for (int i = dfsStackAsArray.Length - 1; i >= 0; i--)
{
Block b = dfsStackAsArray[i];
for (int j = b.Cmds.Count - 1; j >= 0; j--)
{
Cmd cmd = b.Cmds[j];
if (cmd is AssumeCmd)
{
AssumeCmd assumeCmd = cmd as AssumeCmd;
returnExpr = Expr.And(new OldExpr(Token.NoToken, assumeCmd.Expr), returnExpr);
}
else if (cmd is AssignCmd)
{
AssignCmd assignCmd = (cmd as AssignCmd).AsSimpleAssignCmd;
Dictionary <Variable, Expr> map = new Dictionary <Variable, Expr>();
for (int k = 0; k < assignCmd.Lhss.Count; k++)
{
map[assignCmd.Lhss[k].DeepAssignedVariable] = assignCmd.Rhss[k];
}
Substitution subst = Substituter.SubstitutionFromHashtable(new Dictionary <Variable, Expr>());
Substitution oldSubst = Substituter.SubstitutionFromHashtable(map);
returnExpr = (Expr) new MySubstituter(subst, oldSubst).Visit(returnExpr);
}
else if (cmd is HavocCmd)
{
HavocCmd havocCmd = cmd as HavocCmd;
List <Variable> existVars = new List <Variable>();
Dictionary <Variable, Expr> map = new Dictionary <Variable, Expr>();
foreach (IdentifierExpr ie in havocCmd.Vars)
{
BoundVariable bv = GetBoundVariable(ie.Decl.TypedIdent.Type);
map[ie.Decl] = new IdentifierExpr(Token.NoToken, bv);
existVars.Add(bv);
}
Substitution subst = Substituter.SubstitutionFromHashtable(new Dictionary <Variable, Expr>());
Substitution oldSubst = Substituter.SubstitutionFromHashtable(map);
returnExpr = new ExistsExpr(Token.NoToken, existVars, (Expr) new MySubstituter(subst, oldSubst).Visit(returnExpr));
}
else
{
Debug.Assert(false);
}
}
}
return(returnExpr);
}
private void CreateFailurePreservationChecker(Program program, ActionInfo first, ActionInfo second)
{
Tuple <ActionInfo, ActionInfo> actionPair = new Tuple <ActionInfo, ActionInfo>(first, second);
if (failurePreservationCheckerCache.Contains(actionPair))
{
return;
}
failurePreservationCheckerCache.Add(actionPair);
List <Variable> inputs = new List <Variable>();
inputs.AddRange(first.thisInParams);
inputs.AddRange(second.thatInParams);
Expr transitionRelation = (new TransitionRelationComputation(program, second)).Compute();
Expr expr = Expr.True;
foreach (AssertCmd assertCmd in first.thisGate)
{
expr = Expr.And(assertCmd.Expr, expr);
}
List <Requires> requires = DisjointnessRequires(program, first, second);
requires.Add(new Requires(false, Expr.Not(expr)));
foreach (AssertCmd assertCmd in second.thatGate)
{
requires.Add(new Requires(false, assertCmd.Expr));
}
Dictionary <Variable, Expr> map = new Dictionary <Variable, Expr>();
Dictionary <Variable, Expr> oldMap = new Dictionary <Variable, Expr>();
List <Variable> boundVars = new List <Variable>();
foreach (Variable v in program.GlobalVariables())
{
BoundVariable bv = new BoundVariable(Token.NoToken, new TypedIdent(Token.NoToken, "post_" + v.Name, v.TypedIdent.Type));
boundVars.Add(bv);
map[v] = new IdentifierExpr(Token.NoToken, bv);
}
foreach (Variable v in second.thatOutParams)
{
{
BoundVariable bv = new BoundVariable(Token.NoToken, new TypedIdent(Token.NoToken, "post_" + v.Name, v.TypedIdent.Type));
boundVars.Add(bv);
map[v] = new IdentifierExpr(Token.NoToken, bv);
}
{
BoundVariable bv = new BoundVariable(Token.NoToken, new TypedIdent(Token.NoToken, "pre_" + v.Name, v.TypedIdent.Type));
boundVars.Add(bv);
oldMap[v] = new IdentifierExpr(Token.NoToken, bv);
}
}
foreach (Variable v in second.thatAction.LocVars)
{
BoundVariable bv = new BoundVariable(Token.NoToken, new TypedIdent(Token.NoToken, "pre_" + v.Name, v.TypedIdent.Type));
boundVars.Add(bv);
oldMap[v] = new IdentifierExpr(Token.NoToken, bv);
}
Expr ensuresExpr = Expr.And(transitionRelation, Expr.Not(expr));
if (boundVars.Count > 0)
{
Substitution subst = Substituter.SubstitutionFromHashtable(map);
Substitution oldSubst = Substituter.SubstitutionFromHashtable(oldMap);
ensuresExpr = new ExistsExpr(Token.NoToken, boundVars, (Expr) new MySubstituter(subst, oldSubst).Visit(ensuresExpr));
}
List <Ensures> ensures = new List <Ensures>();
ensures.Add(new Ensures(false, ensuresExpr));
List <Block> blocks = new List <Block>();
blocks.Add(new Block(Token.NoToken, "L", new List <Cmd>(), new ReturnCmd(Token.NoToken)));
string checkerName = string.Format("FailurePreservationChecker_{0}_{1}", first.proc.Name, second.proc.Name);
List <IdentifierExpr> globalVars = new List <IdentifierExpr>();
program.GlobalVariables().Iter(x => globalVars.Add(new IdentifierExpr(Token.NoToken, x)));
Procedure proc = new Procedure(Token.NoToken, checkerName, new List <TypeVariable>(), inputs, new List <Variable>(), requires, globalVars, ensures);
Implementation impl = new Implementation(Token.NoToken, checkerName, new List <TypeVariable>(), inputs, new List <Variable>(), new List <Variable>(), blocks);
impl.Proc = proc;
this.decls.Add(impl);
this.decls.Add(proc);
}
private Expr CalculatePathCondition(PathInfo path)
{
HashSet <Variable> allExistsVars = new HashSet <Variable>(firstExistsVars.Union(secondExistsVars));
HashSet <Variable> usedExistsVars = new HashSet <Variable>();
Dictionary <Variable, Expr> existsSubstitutionMap = new Dictionary <Variable, Expr>();
List <Expr> inferredSelectEqualities = new List <Expr>();
foreach (Variable v in path.varToExpr.Keys.Except(postExistVars))
{
var expr = path.varToExpr[v];
usedExistsVars.UnionWith(VariableCollector.Collect(expr).Intersect(allExistsVars));
IdentifierExpr ie = expr as IdentifierExpr;
if (ie != null && IsExistsVar(ie.Decl) && !existsSubstitutionMap.ContainsKey(ie.Decl))
{
existsSubstitutionMap[ie.Decl] = Expr.Ident(v);
}
else if (IsMapStoreExpr(expr))
{
inferredSelectEqualities.Add(GenerateEqualityWithSelect(expr as NAryExpr, Expr.Ident(v)));
}
}
foreach (Expr expr in path.pathExprs)
{
usedExistsVars.UnionWith(VariableCollector.Collect(expr).Intersect(allExistsVars));
}
InferSubstitution(allExistsVars, existsSubstitutionMap, path.pathExprs, inferredSelectEqualities);
List <Expr> triggerExprs = new List <Expr>();
List <Variable> quantifiedVars = new List <Variable>();
foreach (var v in usedExistsVars.Except(existsSubstitutionMap.Keys))
{
var triggerFun = TriggerFunction(v); // this call populates existsVars[v]
var quantifiedVar = existsVars[v];
triggerExprs.Add(
new NAryExpr(Token.NoToken,
new FunctionCall(triggerFun),
new Expr[] { Expr.Ident(quantifiedVar) }));
quantifiedVars.Add(quantifiedVar);
existsSubstitutionMap[v] = Expr.Ident(quantifiedVar);
}
Substitution subst = Substituter.SubstitutionFromHashtable(existsSubstitutionMap);
List <Expr> returnExprs = new List <Expr>();
foreach (Variable v in path.varToExpr.Keys.Except(postExistVars))
{
Expr withOldExpr = MyDuplicator.Duplicate(path.varToExpr[v]);
var substExpr = Expr.Eq(Expr.Ident(v), Substituter.Apply(subst, withOldExpr));
substExpr.Type = Type.Bool;
returnExprs.Add(substExpr);
}
foreach (Expr x in path.pathExprs)
{
var withOldExpr = MyDuplicator.Duplicate(x);
returnExprs.Add(Substituter.Apply(subst, withOldExpr));
}
var returnExpr = Expr.And(returnExprs);
if (quantifiedVars.Count > 0)
{
if (first == null)
{
returnExpr = new ExistsExpr(Token.NoToken, quantifiedVars, returnExpr);
}
else
{
returnExpr = new ExistsExpr(Token.NoToken,
quantifiedVars,
new Trigger(Token.NoToken, true, triggerExprs),
returnExpr);
}
}
return(returnExpr);
}
private void CreateFailurePreservationChecker(Program program, ActionInfo first, ActionInfo second)
{
Tuple<ActionInfo, ActionInfo> actionPair = new Tuple<ActionInfo, ActionInfo>(first, second);
if (failurePreservationCheckerCache.Contains(actionPair))
return;
failurePreservationCheckerCache.Add(actionPair);
List<Variable> inputs = new List<Variable>();
inputs.AddRange(first.thisInParams);
inputs.AddRange(second.thatInParams);
Expr transitionRelation = (new TransitionRelationComputation(program, second)).Compute();
Expr expr = Expr.True;
foreach (AssertCmd assertCmd in first.thisGate)
{
expr = Expr.And(assertCmd.Expr, expr);
}
List<Requires> requires = DisjointnessRequires(program, first, second);
requires.Add(new Requires(false, Expr.Not(expr)));
foreach (AssertCmd assertCmd in second.thatGate)
{
requires.Add(new Requires(false, assertCmd.Expr));
}
Dictionary<Variable, Expr> map = new Dictionary<Variable, Expr>();
Dictionary<Variable, Expr> oldMap = new Dictionary<Variable, Expr>();
List<Variable> boundVars = new List<Variable>();
foreach (Variable v in program.GlobalVariables())
{
BoundVariable bv = new BoundVariable(Token.NoToken, new TypedIdent(Token.NoToken, "post_" + v.Name, v.TypedIdent.Type));
boundVars.Add(bv);
map[v] = new IdentifierExpr(Token.NoToken, bv);
}
foreach (Variable v in second.thatOutParams)
{
{
BoundVariable bv = new BoundVariable(Token.NoToken, new TypedIdent(Token.NoToken, "post_" + v.Name, v.TypedIdent.Type));
boundVars.Add(bv);
map[v] = new IdentifierExpr(Token.NoToken, bv);
}
{
BoundVariable bv = new BoundVariable(Token.NoToken, new TypedIdent(Token.NoToken, "pre_" + v.Name, v.TypedIdent.Type));
boundVars.Add(bv);
oldMap[v] = new IdentifierExpr(Token.NoToken, bv);
}
}
foreach (Variable v in second.thatAction.LocVars)
{
BoundVariable bv = new BoundVariable(Token.NoToken, new TypedIdent(Token.NoToken, "pre_" + v.Name, v.TypedIdent.Type));
boundVars.Add(bv);
oldMap[v] = new IdentifierExpr(Token.NoToken, bv);
}
Expr ensuresExpr = Expr.And(transitionRelation, Expr.Not(expr));
if (boundVars.Count > 0)
{
Substitution subst = Substituter.SubstitutionFromHashtable(map);
Substitution oldSubst = Substituter.SubstitutionFromHashtable(oldMap);
ensuresExpr = new ExistsExpr(Token.NoToken, boundVars, (Expr)new MySubstituter(subst, oldSubst).Visit(ensuresExpr));
}
List<Ensures> ensures = new List<Ensures>();
ensures.Add(new Ensures(false, ensuresExpr));
List<Block> blocks = new List<Block>();
blocks.Add(new Block(Token.NoToken, "L", new List<Cmd>(), new ReturnCmd(Token.NoToken)));
string checkerName = string.Format("FailurePreservationChecker_{0}_{1}", first.proc.Name, second.proc.Name);
List<IdentifierExpr> globalVars = new List<IdentifierExpr>();
program.GlobalVariables().Iter(x => globalVars.Add(new IdentifierExpr(Token.NoToken, x)));
Procedure proc = new Procedure(Token.NoToken, checkerName, new List<TypeVariable>(), inputs, new List<Variable>(), requires, globalVars, ensures);
Implementation impl = new Implementation(Token.NoToken, checkerName, new List<TypeVariable>(), inputs, new List<Variable>(), new List<Variable>(), blocks);
impl.Proc = proc;
this.decls.Add(impl);
this.decls.Add(proc);
}
private Expr CalculatePathCondition(PathInfo path)
{
HashSet<Variable> allExistsVars = new HashSet<Variable>(firstExistsVars.Union(secondExistsVars));
HashSet<Variable> usedExistsVars = new HashSet<Variable>();
Dictionary<Variable, Expr> existsSubstitutionMap = new Dictionary<Variable, Expr>();
List<Expr> inferredSelectEqualities = new List<Expr>();
foreach (Variable v in path.varToExpr.Keys.Except(postExistVars))
{
var expr = path.varToExpr[v];
usedExistsVars.UnionWith(VariableCollector.Collect(expr).Intersect(allExistsVars));
IdentifierExpr ie = expr as IdentifierExpr;
if (ie != null && IsExistsVar(ie.Decl) && !existsSubstitutionMap.ContainsKey(ie.Decl))
{
existsSubstitutionMap[ie.Decl] = Expr.Ident(v);
}
else if (IsMapStoreExpr(expr))
{
inferredSelectEqualities.Add(GenerateEqualityWithSelect(expr as NAryExpr, Expr.Ident(v)));
}
}
foreach (Expr expr in path.pathExprs)
{
usedExistsVars.UnionWith(VariableCollector.Collect(expr).Intersect(allExistsVars));
}
InferSubstitution(allExistsVars, existsSubstitutionMap, path.pathExprs, inferredSelectEqualities);
List<Expr> triggerExprs = new List<Expr>();
List<Variable> quantifiedVars = new List<Variable>();
foreach (var v in usedExistsVars.Except(existsSubstitutionMap.Keys))
{
var triggerFun = TriggerFunction(v); // this call populates existsVars[v]
var quantifiedVar = existsVars[v];
triggerExprs.Add(
new NAryExpr(Token.NoToken,
new FunctionCall(triggerFun),
new Expr[] { Expr.Ident(quantifiedVar) }));
quantifiedVars.Add(quantifiedVar);
existsSubstitutionMap[v] = Expr.Ident(quantifiedVar);
}
Substitution subst = Substituter.SubstitutionFromHashtable(existsSubstitutionMap);
List<Expr> returnExprs = new List<Expr>();
foreach (Variable v in path.varToExpr.Keys.Except(postExistVars))
{
Expr withOldExpr = MyDuplicator.Duplicate(path.varToExpr[v]);
var substExpr = Expr.Eq(Expr.Ident(v), Substituter.Apply(subst, withOldExpr));
substExpr.Type = Type.Bool;
returnExprs.Add(substExpr);
}
foreach (Expr x in path.pathExprs)
{
var withOldExpr = MyDuplicator.Duplicate(x);
returnExprs.Add(Substituter.Apply(subst, withOldExpr));
}
var returnExpr = Expr.And(returnExprs);
if (quantifiedVars.Count > 0)
{
if (first == null)
{
returnExpr = new ExistsExpr(Token.NoToken, quantifiedVars, returnExpr);
}
else
{
returnExpr = new ExistsExpr(Token.NoToken,
quantifiedVars,
new Trigger(Token.NoToken, true, triggerExprs),
returnExpr);
}
}
return returnExpr;
}
void AtomExpression(out Expr/*!*/ e) {
Contract.Ensures(Contract.ValueAtReturn(out e) != null); IToken/*!*/ x; int n; BigNum bn; BigDec bd; BigFloat bf;
List<Expr>/*!*/ es; List<Variable>/*!*/ ds; Trigger trig;
List<TypeVariable>/*!*/ typeParams;
IdentifierExpr/*!*/ id;
QKeyValue kv;
e = dummyExpr;
List<Variable>/*!*/ locals;
List<Block/*!*/>/*!*/ blocks;
switch (la.kind) {
case 83: {
Get();
e = new LiteralExpr(t, false);
break;
}
case 84: {
Get();
e = new LiteralExpr(t, true);
break;
}
case 3: {
Nat(out bn);
e = new LiteralExpr(t, bn);
break;
}
case 5: case 6: {
Dec(out bd);
e = new LiteralExpr(t, bd);
break;
}
case 7: {
Float(out bf);
e = new LiteralExpr(t, bf);
break;
}
case 2: {
BvLit(out bn, out n);
e = new LiteralExpr(t, bn, n);
break;
}
case 1: {
Ident(out x);
id = new IdentifierExpr(x, x.val); e = id;
if (la.kind == 10) {
Get();
if (StartOf(9)) {
Expressions(out es);
e = new NAryExpr(x, new FunctionCall(id), es);
} else if (la.kind == 11) {
e = new NAryExpr(x, new FunctionCall(id), new List<Expr>());
} else SynErr(124);
Expect(11);
}
break;
}
case 85: {
Get();
x = t;
Expect(10);
Expression(out e);
Expect(11);
e = new OldExpr(x, e);
break;
}
case 15: {
Get();
x = t;
Expect(10);
Expression(out e);
Expect(11);
e = new NAryExpr(x, new ArithmeticCoercion(x, ArithmeticCoercion.CoercionType.ToInt), new List<Expr>{ e });
break;
}
case 16: {
Get();
x = t;
Expect(10);
Expression(out e);
Expect(11);
e = new NAryExpr(x, new ArithmeticCoercion(x, ArithmeticCoercion.CoercionType.ToReal), new List<Expr>{ e });
break;
}
case 10: {
Get();
if (StartOf(9)) {
Expression(out e);
if (e is BvBounds)
this.SemErr("parentheses around bitvector bounds " +
"are not allowed");
} else if (la.kind == 89 || la.kind == 90) {
Forall();
x = t;
QuantifierBody(x, out typeParams, out ds, out kv, out trig, out e);
if (typeParams.Count + ds.Count > 0)
e = new ForallExpr(x, typeParams, ds, kv, trig, e);
} else if (la.kind == 91 || la.kind == 92) {
Exists();
x = t;
QuantifierBody(x, out typeParams, out ds, out kv, out trig, out e);
if (typeParams.Count + ds.Count > 0)
e = new ExistsExpr(x, typeParams, ds, kv, trig, e);
} else if (la.kind == 93 || la.kind == 94) {
Lambda();
x = t;
QuantifierBody(x, out typeParams, out ds, out kv, out trig, out e);
if (trig != null)
SemErr("triggers not allowed in lambda expressions");
if (typeParams.Count + ds.Count > 0)
e = new LambdaExpr(x, typeParams, ds, kv, e);
} else SynErr(125);
Expect(11);
break;
}
case 41: {
IfThenElseExpression(out e);
break;
}
case 86: {
CodeExpression(out locals, out blocks);
e = new CodeExpr(locals, blocks);
break;
}
default: SynErr(126); break;
}
}
private void IntroduceAndAssignBoundVars(int indent, ExistsExpr exists, TextWriter wr) {
Contract.Requires(0 <= indent);
Contract.Requires(exists != null);
Contract.Assume(exists.Bounds != null); // follows from successful resolution
Contract.Assert(exists.Range == null); // follows from invariant of class IfStmt
foreach (var bv in exists.BoundVars) {
TrLocalVar(bv, false, indent, wr);
}
var ivars = exists.BoundVars.ConvertAll(bv => (IVariable)bv);
TrAssignSuchThat(indent, ivars, exists.Term, exists.Bounds, exists.tok.line, wr, false);
}
void ExistentialGuard(out Expression e, bool allowLambda)
{
var bvars = new List<BoundVar>();
BoundVar bv; IToken x;
Attributes attrs = null;
Expression body;
IdentTypeOptional(out bv);
bvars.Add(bv); x = bv.tok;
while (la.kind == 22) {
Get();
IdentTypeOptional(out bv);
bvars.Add(bv);
}
while (la.kind == 46) {
Attribute(ref attrs);
}
Expect(25);
Expression(out body, true, allowLambda);
e = new ExistsExpr(x, bvars, null, body, attrs);
}
public void CachedHashCodeExistsExpr()
{
var x = new BoundVariable(Token.NoToken, new TypedIdent(Token.NoToken, "x", BasicType.Int));
var y = new BoundVariable(Token.NoToken, new TypedIdent(Token.NoToken, "x", BasicType.Int));
var body = Expr.Gt (new IdentifierExpr (Token.NoToken, x, /*immutable=*/true),
new IdentifierExpr(Token.NoToken, y, /*immutable=*/true));
var exists = new ExistsExpr(Token.NoToken, new List<Variable> () {x, y }, body, /*immutable=*/ true);
Assert.AreEqual(exists.ComputeHashCode(), exists.GetHashCode());
}
public virtual Expr VisitExistsExpr(ExistsExpr node) {
Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Expr>() != null);
node = (ExistsExpr)this.VisitQuantifierExpr(node);
return node;
}
private Expr CalculatePathCondition()
{
Expr returnExpr = Expr.True;
foreach (Variable v in program.GlobalVariables())
{
var eqExpr = Expr.Eq(new IdentifierExpr(Token.NoToken, v), new OldExpr(Token.NoToken, new IdentifierExpr(Token.NoToken, v)));
returnExpr = Expr.And(eqExpr, returnExpr);
}
if (first != null)
{
foreach (Variable v in first.thisOutParams)
{
var eqExpr = Expr.Eq(new IdentifierExpr(Token.NoToken, v), new OldExpr(Token.NoToken, new IdentifierExpr(Token.NoToken, v)));
returnExpr = Expr.And(eqExpr, returnExpr);
}
}
foreach (Variable v in second.thatOutParams)
{
var eqExpr = Expr.Eq(new IdentifierExpr(Token.NoToken, v), new OldExpr(Token.NoToken, new IdentifierExpr(Token.NoToken, v)));
returnExpr = Expr.And(eqExpr, returnExpr);
}
Block[] dfsStackAsArray = dfsStack.Reverse().ToArray();
for (int i = dfsStackAsArray.Length - 1; i >= 0; i--)
{
Block b = dfsStackAsArray[i];
for (int j = b.Cmds.Count - 1; j >= 0; j--)
{
Cmd cmd = b.Cmds[j];
if (cmd is AssumeCmd)
{
AssumeCmd assumeCmd = cmd as AssumeCmd;
returnExpr = Expr.And(new OldExpr(Token.NoToken, assumeCmd.Expr), returnExpr);
}
else if (cmd is AssignCmd)
{
AssignCmd assignCmd = (cmd as AssignCmd).AsSimpleAssignCmd;
Dictionary<Variable, Expr> map = new Dictionary<Variable, Expr>();
for (int k = 0; k < assignCmd.Lhss.Count; k++)
{
map[assignCmd.Lhss[k].DeepAssignedVariable] = assignCmd.Rhss[k];
}
Substitution subst = Substituter.SubstitutionFromHashtable(new Dictionary<Variable, Expr>());
Substitution oldSubst = Substituter.SubstitutionFromHashtable(map);
returnExpr = (Expr) new MySubstituter(subst, oldSubst).Visit(returnExpr);
}
else if (cmd is HavocCmd)
{
HavocCmd havocCmd = cmd as HavocCmd;
List<Variable> existVars = new List<Variable>();
Dictionary<Variable, Expr> map = new Dictionary<Variable, Expr>();
foreach (IdentifierExpr ie in havocCmd.Vars)
{
BoundVariable bv = GetBoundVariable(ie.Decl.TypedIdent.Type);
map[ie.Decl] = new IdentifierExpr(Token.NoToken, bv);
existVars.Add(bv);
}
Substitution subst = Substituter.SubstitutionFromHashtable(new Dictionary<Variable, Expr>());
Substitution oldSubst = Substituter.SubstitutionFromHashtable(map);
returnExpr = new ExistsExpr(Token.NoToken, existVars, (Expr) new MySubstituter(subst, oldSubst).Visit(returnExpr));
}
else
{
Debug.Assert(false);
}
}
}
return returnExpr;
}
private Expr SubsetExprs(LinearDomain domain, HashSet<Variable> scope, Variable partition, int count, Expr expr)
{
foreach (Variable v in scope)
{
if (!domain.collectors.ContainsKey(v.TypedIdent.Type)) continue;
Expr ie = new NAryExpr(Token.NoToken, new FunctionCall(domain.collectors[v.TypedIdent.Type]), new List<Expr> { Expr.Ident(v) });
expr = Expr.And(SubsetExpr(domain, ie, partition, count), expr);
count++;
}
expr = new ExistsExpr(Token.NoToken, new List<Variable> { partition }, expr);
expr.Resolve(new ResolutionContext(null));
expr.Typecheck(new TypecheckingContext(null));
return expr;
}
public Expr DisjointnessExpr(string domainName, HashSet<Variable> scope)
{
LinearDomain domain = linearDomains[domainName];
BoundVariable partition = new BoundVariable(Token.NoToken, new TypedIdent(Token.NoToken, string.Format("partition_{0}", domainName), new MapType(Token.NoToken, new List<TypeVariable>(), new List<Type> { domain.elementType }, Microsoft.Boogie.Type.Int)));
Expr disjointExpr = Expr.True;
int count = 0;
foreach (Variable v in scope)
{
IdentifierExpr ie = new IdentifierExpr(Token.NoToken, v);
Expr e = new NAryExpr(Token.NoToken, new FunctionCall(domain.mapConstInt), new List<Expr>{ new LiteralExpr(Token.NoToken, Microsoft.Basetypes.BigNum.FromInt(count++)) } );
e = new NAryExpr(Token.NoToken, new FunctionCall(domain.mapEqInt), new List<Expr> { new IdentifierExpr(Token.NoToken, partition), e } );
e = new NAryExpr(Token.NoToken, new FunctionCall(domain.mapImpBool), new List<Expr> { v.TypedIdent.Type is MapType ? ie : Singleton(ie, domainName), e } );
e = Expr.Binary(BinaryOperator.Opcode.Eq, e, new NAryExpr(Token.NoToken, new FunctionCall(domain.mapConstBool), new List<Expr> { Expr.True }));
disjointExpr = Expr.Binary(BinaryOperator.Opcode.And, e, disjointExpr);
}
var expr = new ExistsExpr(Token.NoToken, new List<Variable> { partition }, disjointExpr);
expr.Resolve(new ResolutionContext(null));
expr.Typecheck(new TypecheckingContext(null));
return expr;
}
public void ProtectedExistsExprBody()
{
var x = new BoundVariable(Token.NoToken, new TypedIdent(Token.NoToken, "x", BasicType.Int));
var y = new BoundVariable(Token.NoToken, new TypedIdent(Token.NoToken, "x", BasicType.Int));
var xId = new IdentifierExpr(Token.NoToken, x, /*immutable=*/true);
var yId = new IdentifierExpr(Token.NoToken, y, /*immutable=*/true);
var body = Expr.Gt(xId, yId);
var exists = new ExistsExpr(Token.NoToken, new List<Variable> () { x, y }, body, /*immutable=*/true);
exists.Body = Expr.Lt(xId, yId); // Changing the body of an immutable ExistsExpr should fail
}
/// <summary>
///
/// </summary>
/// <param name="methodCall"></param>
/// <remarks>Stub, This one really needs comments!</remarks>
public override void TraverseChildren(IMethodCall methodCall) {
var resolvedMethod = ResolveUnspecializedMethodOrThrow(methodCall.MethodToCall);
Bpl.IToken methodCallToken = methodCall.Token();
if (this.sink.Options.getMeHere) {
// TODO: Get a method reference so this isn't a string comparison?
var methodName = MemberHelper.GetMethodSignature(methodCall.MethodToCall, NameFormattingOptions.None);
if (methodName.Equals("GetMeHere.GetMeHere.Assert")) {
// for now, just translate it as "assert e"
this.Traverse(methodCall.Arguments.First());
Bpl.Expr e = this.TranslatedExpressions.Pop();
this.StmtTraverser.StmtBuilder.Add(new Bpl.AssertCmd(methodCallToken, e));
return;
}
}
// Handle type equality specially when it is testing against a constant, i.e., o.GetType() == typeof(T)
if (IsOperator(resolvedMethod) && !IsConversionOperator(resolvedMethod) &&
TypeHelper.TypesAreEquivalent(resolvedMethod.ContainingType, this.sink.host.PlatformType.SystemType)) {
// REVIEW: Assume the only operators on System.Type are == and !=
var typeToTest = methodCall.Arguments.ElementAtOrDefault(0) as ITypeOf;
IMethodCall callToGetType;
if (typeToTest == null) {
typeToTest = methodCall.Arguments.ElementAtOrDefault(1) as ITypeOf;
callToGetType = methodCall.Arguments.ElementAtOrDefault(0) as IMethodCall;
} else {
callToGetType = methodCall.Arguments.ElementAtOrDefault(1) as IMethodCall;
}
if (typeToTest != null && callToGetType != null &&
TypeHelper.TypesAreEquivalent(callToGetType.MethodToCall.ContainingType, this.sink.host.PlatformType.SystemObject) &&
MemberHelper.GetMethodSignature(callToGetType.MethodToCall).Equals("System.Object.GetType")) {
IExpression objectToTest = callToGetType.ThisArgument;
// generate: $TypeConstructor($DynamicType(o)) == TypeConstructorId
var typeConstructorId = this.sink.FindOrDefineType(typeToTest.TypeToGet.ResolvedType).ConstructorId;
Contract.Assume(typeConstructorId != null);
this.Traverse(objectToTest);
var e = this.TranslatedExpressions.Pop();
var exprs = new List<Bpl.Expr>(new Bpl.Expr[] {this.sink.Heap.DynamicType(e)});
Bpl.Expr typeTestExpression =
Bpl.Expr.Binary(Bpl.BinaryOperator.Opcode.Eq,
new Bpl.NAryExpr(methodCallToken, new Bpl.FunctionCall(sink.Heap.TypeConstructorFunction), exprs),
Bpl.Expr.Ident(typeConstructorId));
if (MemberHelper.GetMethodSignature(resolvedMethod).Equals("System.Type.op_Inequality"))
typeTestExpression = Bpl.Expr.Unary( methodCallToken, Bpl.UnaryOperator.Opcode.Not, typeTestExpression);
this.TranslatedExpressions.Push(typeTestExpression);
return;
}
}
// Handle calls to Contract.ForAll and Contract.Exists specially (if they are to the overloads that take two ints and a predicate on ints)
if (resolvedMethod.ContainingTypeDefinition.InternedKey == this.sink.host.PlatformType.SystemDiagnosticsContractsContract.InternedKey)
{
var methodName = resolvedMethod.Name.Value;
if (methodCall.Arguments.Count() == 3 && (methodName == "ForAll" || methodName == "Exists"))
{
var noToken = Bpl.Token.NoToken;
this.Traverse(methodCall.Arguments.ElementAt(0));
var lb = this.TranslatedExpressions.Pop();
this.Traverse(methodCall.Arguments.ElementAt(1));
var ub = this.TranslatedExpressions.Pop();
var delegateArgument = methodCall.Arguments.ElementAt(2);
this.Traverse(delegateArgument);
var del = this.TranslatedExpressions.Pop();
var boundVar = new Bpl.LocalVariable(noToken, new Bpl.TypedIdent(noToken, TranslationHelper.GenerateTempVarName(), Bpl.Type.Int));
var resultVar = new Bpl.LocalVariable(noToken, new Bpl.TypedIdent(noToken, TranslationHelper.GenerateTempVarName(), Bpl.Type.Bool));
var delegateType = delegateArgument.Type;
var invokeMethod = delegateType.ResolvedType.GetMembersNamed(this.sink.host.NameTable.GetNameFor("Invoke"), false).First() as IMethodReference;
var unspecializedInvokeMethod = Sink.Unspecialize(invokeMethod).ResolvedMethod;
var invokeProcedureInfo = sink.FindOrCreateProcedure(unspecializedInvokeMethod);
var ins = new List<Bpl.Expr>();
ins.Add(del);
var localStmtTraverser = this.StmtTraverser.factory.MakeStatementTraverser(this.sink, this.StmtTraverser.PdbReader, this.contractContext);
var secondArg = new Bpl.NAryExpr(noToken, new Bpl.FunctionCall(this.sink.Heap.Int2Union), new List<Bpl.Expr>(new Bpl.Expr[] {Bpl.Expr.Ident(boundVar)}));
ins.Add(secondArg);
var outs = new List<Bpl.IdentifierExpr>();
outs.Add(Bpl.Expr.Ident(resultVar));
var callCmd = new Bpl.CallCmd(noToken, invokeProcedureInfo.Decl.Name, ins, outs);
var blockCmds = new List<Bpl.Cmd>();
blockCmds.Add(
new Bpl.AssumeCmd(noToken,
Bpl.Expr.Binary(Bpl.BinaryOperator.Opcode.Eq,
new Bpl.NAryExpr(noToken, new Bpl.FunctionCall(this.sink.Heap.Union2Int), new List<Bpl.Expr>(new Bpl.Expr[] {secondArg})),
Bpl.Expr.Ident(boundVar))));
blockCmds.Add(callCmd);
Bpl.Block block = new Bpl.Block(noToken, "A", blockCmds, new Bpl.ReturnExprCmd(noToken, Bpl.Expr.Ident(resultVar)));
Bpl.Expr body = new Bpl.CodeExpr(new List<Bpl.Variable>(new Bpl.Variable[] {resultVar}), new List<Bpl.Block>{block});
Bpl.Expr antecedent = Bpl.Expr.And(Bpl.Expr.Le(lb, Bpl.Expr.Ident(boundVar)), Bpl.Expr.Lt(Bpl.Expr.Ident(boundVar), ub));
Bpl.Expr quantifier;
if (methodName == "ForAll")
{
body = Bpl.Expr.Imp(antecedent, body);
quantifier = new Bpl.ForallExpr(methodCallToken, new List<Bpl.Variable>(new Bpl.Variable[] {boundVar}), body);
}
else
{
body = Bpl.Expr.And(antecedent, body);
quantifier = new Bpl.ExistsExpr(methodCallToken, new List<Bpl.Variable>(new Bpl.Variable[] {boundVar}), body);
}
this.TranslatedExpressions.Push(quantifier);
return;
}
}
List<Bpl.Expr> inexpr;
List<Bpl.IdentifierExpr> outvars;
Bpl.IdentifierExpr thisExpr;
Dictionary<Bpl.IdentifierExpr, Tuple<Bpl.IdentifierExpr,bool>> toBoxed;
var proc = TranslateArgumentsAndReturnProcedure(methodCallToken, methodCall.MethodToCall, resolvedMethod, methodCall.IsStaticCall ? null : methodCall.ThisArgument, methodCall.Arguments, out inexpr, out outvars, out thisExpr, out toBoxed);
string methodname = proc.Name;
var translateAsFunctionCall = proc is Bpl.Function;
bool isAsync = false;
// this code structure is quite chaotic, and some code needs to be evaluated regardless, hence the try-finally
try {
if (!translateAsFunctionCall) {
foreach (var a in resolvedMethod.Attributes) {
if (TypeHelper.GetTypeName(a.Type).EndsWith("AsyncAttribute")) {
isAsync = true;
}
}
}
var deferringCtorCall = resolvedMethod.IsConstructor && methodCall.ThisArgument is IThisReference;
// REVIEW!! Ask Herman: is the above test enough? The following test is used in FindCtorCall.IsDeferringCtor,
// but it doesn't work when the type is a struct S because then "this" has a type of "&S".
//&& TypeHelper.TypesAreEquivalent(resolvedMethod.ContainingType, methodCall.ThisArgument.Type);
if (resolvedMethod.IsConstructor && resolvedMethod.ContainingTypeDefinition.IsStruct && !deferringCtorCall) {
handleStructConstructorCall(methodCall, methodCallToken, inexpr, outvars, thisExpr, proc);
return;
}
Bpl.CallCmd call;
bool isEventAdd = resolvedMethod.IsSpecialName && resolvedMethod.Name.Value.StartsWith("add_");
bool isEventRemove = resolvedMethod.IsSpecialName && resolvedMethod.Name.Value.StartsWith("remove_");
if (isEventAdd || isEventRemove) {
call = translateAddRemoveCall(methodCall, resolvedMethod, methodCallToken, inexpr, outvars, thisExpr, isEventAdd);
} else {
if (translateAsFunctionCall) {
var func = proc as Bpl.Function;
var exprSeq = new List<Bpl.Expr>();
foreach (var e in inexpr) {
exprSeq.Add(e);
}
var callFunction = new Bpl.NAryExpr(methodCallToken, new Bpl.FunctionCall(func), exprSeq);
this.TranslatedExpressions.Push(callFunction);
return;
} else {
EmitLineDirective(methodCallToken);
call = new Bpl.CallCmd(methodCallToken, methodname, inexpr, outvars);
call.IsAsync = isAsync;
this.StmtTraverser.StmtBuilder.Add(call);
}
}
foreach (KeyValuePair<Bpl.IdentifierExpr, Tuple<Bpl.IdentifierExpr,bool>> kv in toBoxed) {
var lhs = kv.Key;
var tuple = kv.Value;
var rhs = tuple.Item1;
Bpl.Expr fromUnion = this.sink.Heap.FromUnion(Bpl.Token.NoToken, lhs.Type, rhs, tuple.Item2);
this.StmtTraverser.StmtBuilder.Add(TranslationHelper.BuildAssignCmd(lhs, fromUnion));
}
if (this.sink.Options.modelExceptions == 2
|| (this.sink.Options.modelExceptions == 1 && this.sink.MethodThrowsExceptions(resolvedMethod))) {
Bpl.Expr expr = Bpl.Expr.Binary(Bpl.BinaryOperator.Opcode.Neq, Bpl.Expr.Ident(this.sink.Heap.ExceptionVariable), Bpl.Expr.Ident(this.sink.Heap.NullRef));
this.StmtTraverser.RaiseException(expr);
}
} finally {
// TODO move away phone related code from the translation, it would be better to have 2 or more translation phases
if (PhoneCodeHelper.instance().PhonePlugin != null) {
if (PhoneCodeHelper.instance().PhoneNavigationToggled) {
if (PhoneCodeHelper.instance().isNavigationCall(methodCall)) {
Bpl.AssignCmd assignCmd = PhoneCodeHelper.instance().createBoogieNavigationUpdateCmd(sink);
this.StmtTraverser.StmtBuilder.Add(assignCmd);
}
}
if (PhoneCodeHelper.instance().PhoneFeedbackToggled) {
if (PhoneCodeHelper.instance().isMethodKnownUIChanger(methodCall)) {
Bpl.AssumeCmd assumeFalse = new Bpl.AssumeCmd(Bpl.Token.NoToken, Bpl.LiteralExpr.False);
this.StmtTraverser.StmtBuilder.Add(assumeFalse);
}
}
}
}
}
public override Expr VisitExistsExpr(ExistsExpr node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Expr>() != null);
return base.VisitExistsExpr((ExistsExpr)node.Clone());
}
private Expr CalculatePathCondition(PathInfo path)
{
Expr returnExpr = Expr.True;
HashSet<Variable> existsVars = path.existsVars;
Dictionary<Variable, Expr> existsMap = new Dictionary<Variable, Expr>();
Dictionary<Variable, Expr> varToExpr = path.varToExpr;
foreach (Variable v in varToExpr.Keys)
{
if (postExistVars.Contains(v)) continue;
IdentifierExpr ie = varToExpr[v] as IdentifierExpr;
if (ie != null && !existsMap.ContainsKey(ie.Decl) && existsVars.Contains(ie.Decl))
{
existsMap[ie.Decl] = Expr.Ident(v);
existsVars.Remove(ie.Decl);
}
else
{
returnExpr = Expr.And(returnExpr, Expr.Eq(Expr.Ident(v), (new MyDuplicator()).VisitExpr(varToExpr[v])));
returnExpr.Type = Type.Bool;
}
}
List<Expr> pathExprs = new List<Expr>();
path.pathExprs.ForEach(x => pathExprs.Add((new MyDuplicator()).VisitExpr(x)));
foreach (Expr x in pathExprs)
{
Variable boundVar;
Expr boundVarExpr;
if (InferSubstitution(x, out boundVar, out boundVarExpr) && existsVars.Contains(boundVar))
{
existsMap[boundVar] = boundVarExpr;
existsVars.Remove(boundVar);
}
else
{
returnExpr = Expr.And(returnExpr, x);
returnExpr.Type = Type.Bool;
}
}
returnExpr = Substituter.Apply(Substituter.SubstitutionFromHashtable(existsMap), returnExpr);
if (existsVars.Count > 0)
{
returnExpr = new ExistsExpr(Token.NoToken, new List<Variable>(existsVars), returnExpr);
}
return returnExpr;
}
