private bool TryComputeNAryExprs(IdentifierExpr id)
{
var toRemove = new HashSet <Expr>();
foreach (var expr in this.ExpressionMap[id].Keys.ToList())
{
if (!(expr is NAryExpr))
{
continue;
}
int ixs = 0;
if (((expr as NAryExpr).Args[0] is IdentifierExpr) &&
((expr as NAryExpr).Args[0] as IdentifierExpr).Name.StartsWith("$M."))
{
toRemove.Add(expr);
continue;
}
if (PointerAnalysis.ShouldSkipFromAnalysis(expr as NAryExpr))
{
toRemove.Add(expr);
continue;
}
if (PointerAnalysis.IsArithmeticExpression(expr as NAryExpr))
{
toRemove.Add(expr);
continue;
}
Expr p = (expr as NAryExpr).Args[0];
Expr i = (expr as NAryExpr).Args[1];
Expr s = (expr as NAryExpr).Args[2];
if (!(i is LiteralExpr && s is LiteralExpr))
{
toRemove.Add(expr);
continue;
}
ixs = (i as LiteralExpr).asBigNum.ToInt * (s as LiteralExpr).asBigNum.ToInt;
this.ExpressionMap[id].Add(p, this.ExpressionMap[id][expr] + ixs);
toRemove.Add(expr);
}
foreach (var expr in toRemove)
{
this.ExpressionMap[id].Remove(expr);
}
if (this.ExpressionMap[id].Any(val => val.Key is NAryExpr))
{
return(false);
}
return(true);
}
internal bool IsAxiom(IdentifierExpr expr)
{
bool result = false;
if (expr == null)
{
return(result);
}
foreach (var axiom in this.AC.TopLevelDeclarations.OfType <Axiom>())
{
Expr axiomExpr = null;
if (axiom.Expr is NAryExpr)
{
axiomExpr = (axiom.Expr as NAryExpr).Args[0];
}
else
{
axiomExpr = axiom.Expr;
}
if (axiomExpr.ToString().Equals(expr.Name))
{
result = true;
break;
}
}
return(result);
}
public void SimpleForAllWithTrigger()
{
var builder = GetSimpleBuilder();
var freeVarX = GetVariable("x", BasicType.Int);
var xid = new IdentifierExpr(Token.NoToken, freeVarX);
var fb = new FunctionCallBuilder();
var funcCall = fb.CreateUninterpretedFunctionCall("f", BPLType.Int, new List <BPLType>()
{
BPLType.Int
});
var body = builder.Gt(builder.UFC(funcCall, xid), xid);
// Single trigger
var triggers = new Microsoft.Boogie.Trigger(Token.NoToken,
/*positive=*/ true,
new List <Expr>()
{
builder.UFC(funcCall, xid)
}, null);
var result = builder.ForAll(new List <Variable>()
{
freeVarX
}, body, triggers);
Assert.AreEqual("(forall x: int :: { f(x) } f(x) > x)", result.ToString());
CheckIsBoolType(result);
}
public VarDefinitionStmt(IdentifierExpr name, IdentifierExpr type, bool isConst, Expression initialValue)
{
_name = name;
_type = type;
_isConst = isConst;
_initialValue = initialValue;
}
public override Expr VisitIdentifierExpr(IdentifierExpr node)
{
if (node.Decl is GlobalVariable)
{
if (!canAccessSharedVars)
{
Error(node, "Shared variable can be accessed only in atomic actions or specifications");
}
else if (this.globalVarToSharedVarInfo.ContainsKey(node.Decl))
{
if (this.globalVarToSharedVarInfo[node.Decl].hideLayerNum < minLayerNum)
{
minLayerNum = this.globalVarToSharedVarInfo[node.Decl].hideLayerNum;
}
if (this.globalVarToSharedVarInfo[node.Decl].introLayerNum > maxLayerNum)
{
maxLayerNum = this.globalVarToSharedVarInfo[node.Decl].introLayerNum;
}
}
else
{
Error(node, "Accessed shared variable must have layer annotation");
}
}
else if (node.Decl is LocalVariable && ghostVars.Contains(node.Decl) && !canAccessGhostVars)
{
Error(node, "Ghost variable can be accessed only in assertions");
}
return(base.VisitIdentifierExpr(node));
}
private Expr ElimPendingAsyncExpr(IdentifierExpr pa)
{
return(Expr.And(
Expr.Or(elim.Keys.Select(a => ExprHelper.FunctionCall(a.pendingAsyncCtor.membership, pa))),
Expr.Gt(Expr.Select(PAs, pa), Expr.Literal(0))
));
}
public void FunctionCallCallsVisitOnAllParametersPassedTest()
{
var target = new EvaluateVisitor();
var functionName = RandomGenerator.String();
var functionNameExpr = new IdentifierExpr(functionName);
var parameters = new[]
{
new VarDefinitionStmt(new IdentifierExpr("A"), new IdentifierExpr("INT"), false, new ConstantExpr(1)),
new VarDefinitionStmt(new IdentifierExpr("B"), new IdentifierExpr("STRING"), false, new ConstantExpr("TEST")),
new VarDefinitionStmt(new IdentifierExpr("C"), new IdentifierExpr("BOOL"), false, new ConstantExpr(true))
};
var values = new Expression[]
{
new ConstantExpr(1),
new ConstantExpr(RandomGenerator.String()),
new ConstantExpr(true)
};
var returnValue = values[1];
var functionDefinition = new FunctionDefinitionExpr(functionNameExpr, parameters,
new ScopeBlockStmt(new[] { new ReturnStmt(returnValue) }), new IdentifierExpr("String"));
var expr = new FunctionCallExpr(functionNameExpr, values);
_scope.DefineIdentifier(functionName, Value.FromObject(functionDefinition));
var actual = target.Visit(expr, _scope);
Assert.AreEqual(((ConstantExpr)returnValue).Value, actual.ToObject());
}
public void IdentifierExprName()
{
var id = new IdentifierExpr(Token.NoToken, "foo", BasicType.Bool, /*immutable=*/ true);
Assert.IsTrue(id.Immutable);
Assert.Throws(typeof(InvalidOperationException), () => id.Name = "foo2");
}
public override ILineObject Generate(GenerationEnvironment env)
{
List <ILineObject> ret = new List <ILineObject>();
if (CheckInstance != null && CheckInstance.Length != 0)
{
ret.Add(new ControlBlock(ControlBlockType.If,
new BiOpExpr(ActorVariableHelper.GenerateGet(CheckInstance), ThisExpr.Instance.MakeIndex("name"), BiOpExpr.Op.NotEqual),
new ILineObject[] {
ThisExpr.Instance.MakeIndex("Release").Call().Statement(),
}).Statement());
}
var ownerActor = new IdentifierExpr("ownerActor");
var x = Position.GenerateX(ownerActor, env);
var y = Position.GenerateY(ownerActor, env);
var setRotation = ThisExpr.Instance.MakeIndex("rz").Assign(ownerActor.MakeIndex("rz")).Statement();
ret.AddRange(new ILineObject[] {
new LocalVarStatement("ownerActor", ActorVariableHelper.GenerateGet("SYS_parent").MakeIndex("wr")),
new ControlBlock(ControlBlockType.If, "ownerActor != null", new ILineObject[] {
ThisExpr.Instance.MakeIndex("x").Assign(x).Statement(),
ThisExpr.Instance.MakeIndex("y").Assign(y).Statement(),
IgnoreRotation ? new SimpleLineObject("") : setRotation,
}).Statement(),
new ControlBlock(ControlBlockType.Else, new ILineObject[] {
ThisExpr.Instance.MakeIndex("Release").Call().Statement(),
}).Statement(),
});
return(new SimpleBlock(ret).Statement());
}
private void FindUseOfFunctionPointers(InstrumentationRegion region, int regionIndex,
IdentifierExpr constant, HashSet <InstrumentationRegion> alreadyFound)
{
if (alreadyFound.Contains(region))
{
return;
}
alreadyFound.Add(region);
var id = region.Implementation().InParams[regionIndex];
if (region.FunctionPointers.Contains(id))
{
return;
}
region.FunctionPointers.Add(id);
foreach (var block in region.Blocks())
{
for (int idx = 0; idx < block.Cmds.Count; idx++)
{
if (!(block.Cmds[idx] is CallCmd))
{
continue;
}
var call = block.Cmds[idx] as CallCmd;
var calleeRegion = this.AC.InstrumentationRegions.Find(val =>
val.Implementation().Name.Equals(call.callee));
if (calleeRegion == null)
{
continue;
}
var indexes = new HashSet <int>();
for (int i = 0; i < call.Ins.Count; i++)
{
if (!(call.Ins[i] is IdentifierExpr))
{
continue;
}
if (id.Name.Equals((call.Ins[i] as IdentifierExpr).Name))
{
indexes.Add(i);
}
}
if (indexes.Count == 0)
{
continue;
}
foreach (var index in indexes)
{
this.FindUseOfFunctionPointers(calleeRegion, index, constant, alreadyFound);
}
}
}
}
bool InferSubstitution(Expr x, out Variable var, out Expr expr)
{
var = null;
expr = null;
NAryExpr naryExpr = x as NAryExpr;
if (naryExpr == null || naryExpr.Fun.FunctionName != "==")
{
return(false);
}
IdentifierExpr arg0 = naryExpr.Args[0] as IdentifierExpr;
if (arg0 != null && arg0.Decl is BoundVariable)
{
var = arg0.Decl;
expr = naryExpr.Args[1];
return(true);
}
IdentifierExpr arg1 = naryExpr.Args[1] as IdentifierExpr;
if (arg1 != null && arg1.Decl is BoundVariable)
{
var = arg1.Decl;
expr = naryExpr.Args[0];
return(true);
}
return(false);
}
public void IdentifierExprName()
{
var id = new IdentifierExpr(Token.NoToken, "foo", BasicType.Bool, /*immutable=*/ true);
Assert.IsTrue(id.Immutable);
id.Name = "foo2";
}
private AssertCmd GenBoundCheck(BOUND_TYPE btype, AccessRecord ar, int arrDim, Variable offsetVar)
{
Expr boundExpr = null;
IdentifierExpr offsetVarExpr = new IdentifierExpr(Token.NoToken, offsetVar);
switch (btype)
{
case BOUND_TYPE.LOWER:
boundExpr = verifier.IntRep.MakeSge(offsetVarExpr, verifier.IntRep.GetLiteral(0, verifier.size_t_bits)); break;
case BOUND_TYPE.UPPER:
boundExpr = verifier.IntRep.MakeSlt(offsetVarExpr, verifier.IntRep.GetLiteral(arrDim, verifier.size_t_bits)); break;
}
return(new AssertCmd(Token.NoToken, boundExpr,
new QKeyValue(Token.NoToken, "array_bounds", new List <object> {
},
new QKeyValue(Token.NoToken, "sourceloc_num", new List <object> {
new LiteralExpr(Token.NoToken, Microsoft.Basetypes.BigNum.FromInt(CurrSourceLocNum))
},
new QKeyValue(Token.NoToken, "check_id", new List <object> {
"bounds_check_state_" + ArraySourceID
},
new QKeyValue(Token.NoToken, "array_name", new List <object> {
ar.v.Name
},
null))))));
}
public InductiveSequentialization(AtomicAction inputAction, AtomicAction outputAction,
AtomicAction invariantAction, Dictionary <AtomicAction, AtomicAction> elim)
{
this.inputAction = inputAction;
this.outputAction = outputAction;
this.invariantAction = invariantAction;
this.elim = elim;
// TODO: check frame computation
// We could compute a tighter frame per check. For example, base/conclusion checkers
// don't have to take the eliminated actions into account.
var frameVars = new List <AtomicAction> {
invariantAction, outputAction, inputAction
}
.Union(elim.Select(kv => kv.Value))
.SelectMany(a => a.gateUsedGlobalVars.Union(a.modifiedGlobalVars)).Distinct();
this.frame = new HashSet <Variable>(frameVars);
this.modifies = frame.Select(Expr.Ident).ToList();
newPAs = Expr.Ident(VarHelper.LocalVariable("newPAs", PendingAsyncMultisetType));
if (HasChoice)
{
choice = Expr.Ident(invariantAction.impl.OutParams.Last());
}
else
{
choice = Expr.Ident(VarHelper.LocalVariable("choice", PendingAsyncType));
}
}
public override Expr VisitIdentifierExpr(IdentifierExpr node)
{
IdentifierExpr newNode;
if (node.Name != node.Decl.Name || node.Name != node.Decl.TypedIdent.Name)
{
Console.WriteLine("Inconsistent variable/ident naming on " + node.Name + " " + node.Decl.Name + " " + node.Decl.TypedIdent.Name);
}
GlobalVariable g = node.Decl as GlobalVariable;
if (g == null)
{
newNode = null;
}
else
{
g = GetNewVar(g);
if (g == null)
{
newNode = null;
}
else
{
//newNode = Expr.Ident(g);
newNode = new IdentifierExpr(Token.NoToken, g);
}
}
return(base.VisitIdentifierExpr(newNode == null ? node : newNode));
}
private void LiteralArgumentAnalyser(Procedure p, int arg)
{
LiteralExpr literal = null;
foreach (CallCmd callCmd in CallSites[p])
{
if (callCmd.Ins[arg] == null || !(callCmd.Ins[arg] is LiteralExpr))
{
return;
}
LiteralExpr l = callCmd.Ins[arg] as LiteralExpr;
if (literal == null)
{
literal = l;
}
else if (!literal.Equals(l))
{
return;
}
}
Expr e;
e = new IdentifierExpr(Token.NoToken, p.InParams[arg]);
e = Expr.Eq(e, literal);
p.Requires.Add(new Requires(false, e));
}
private Expr CollectBooleanAssignment(IdentifierExpr glob, Variable assignedVar)
{
return(new NAryExpr(Token.NoToken, new FunctionCall(collectBoolFunc), new List <Expr>()
{
glob, IdentifierExpr.Ident(assignedVar)
}));
}
public void ParallelSymbolicAssignment()
{
p = LoadProgramFrom(@"
procedure main()
{
var x:int;
var y:int;
assert {:symbooglix_bp ""before""} true;
x, y := y, x;
assert {:symbooglix_bp ""after""} true;
}
", "file.bpl");
e = GetExecutor(p, new DFSStateScheduler(), GetSolver());
int count = 0;
IdentifierExpr symbolicForx = null;
IdentifierExpr symbolicFory = null;
e.BreakPointReached += delegate(object sender, Executor.BreakPointEventArgs eventArgs)
{
switch (eventArgs.Name)
{
case "before":
{
var vAndExprForx = e.CurrentState.GetInScopeVariableAndExprByName("x");
Assert.IsInstanceOf <IdentifierExpr>(vAndExprForx.Value);
Assert.IsInstanceOf <SymbolicVariable>((vAndExprForx.Value as IdentifierExpr).Decl);
symbolicForx = vAndExprForx.Value as IdentifierExpr;
var vAndExprFory = e.CurrentState.GetInScopeVariableAndExprByName("y");
Assert.IsInstanceOf <IdentifierExpr>(vAndExprFory.Value);
Assert.IsInstanceOf <SymbolicVariable>((vAndExprFory.Value as IdentifierExpr).Decl);
symbolicFory = vAndExprFory.Value as IdentifierExpr;
}
break;
case "after":
{
Assert.IsNotNull(symbolicForx);
Assert.IsNotNull(symbolicFory);
// Check that swapped happened
var vAndExprForNewx = e.CurrentState.GetInScopeVariableAndExprByName("x");
Assert.AreSame(symbolicFory, vAndExprForNewx.Value);
var vAndExprForNewy = e.CurrentState.GetInScopeVariableAndExprByName("y");
Assert.AreSame(symbolicForx, vAndExprForNewy.Value);
}
break;
default:
Assert.Fail("unrecognised breakpoint");
break;
}
++count;
};
e.Run(GetMain(p));
Assert.AreEqual(2, count);
}
public QuantifierExpr RewriteMatchingLoops(QuantifierWithTriggers q)
{
// rewrite quantifier to avoid mathing loops
// before:
// assert forall i :: 0 <= i < a.Length-1 ==> a[i] <= a[i+1];
// after:
// assert forall i,j :: j == i+1 ==> 0 <= i < a.Length-1 ==> a[i] <= a[i+1];
substMap = new Dictionary <Expression, IdentifierExpr>();
usedMap = new Dictionary <Expression, IdentifierExpr>();
foreach (var m in q.LoopingMatches)
{
var e = m.OriginalExpr;
if (TriggersCollector.IsPotentialTriggerCandidate(e) && triggersCollector.IsTriggerKiller(e))
{
foreach (var sub in e.SubExpressions)
{
if (triggersCollector.IsTriggerKiller(sub) && (!TriggersCollector.IsPotentialTriggerCandidate(sub)))
{
IdentifierExpr ie;
if (!substMap.TryGetValue(sub, out ie))
{
var newBv = new BoundVar(sub.tok, "_t#" + substMap.Count, sub.Type);
ie = new IdentifierExpr(sub.tok, newBv.Name);
ie.Var = newBv;
ie.Type = newBv.Type;
substMap[sub] = ie;
}
}
}
}
}
var expr = (QuantifierExpr)q.quantifier;
if (substMap.Count > 0)
{
var s = new Translator.ExprSubstituter(substMap);
expr = s.Substitute(q.quantifier) as QuantifierExpr;
}
else
{
// make a copy of the expr
if (expr is ForallExpr)
{
expr = new ForallExpr(expr.tok, expr.TypeArgs, expr.BoundVars, expr.Range, expr.Term, TriggerUtils.CopyAttributes(expr.Attributes))
{
Type = expr.Type
};
}
else
{
expr = new ExistsExpr(expr.tok, expr.TypeArgs, expr.BoundVars, expr.Range, expr.Term, TriggerUtils.CopyAttributes(expr.Attributes))
{
Type = expr.Type
};
}
}
return(expr);
}
public override Expr VisitIdentifierExpr(IdentifierExpr node)
{
if (!inold)
{
flag = true;
}
return(base.VisitIdentifierExpr(node));
}
public override Expr VisitIdentifierExpr(IdentifierExpr node)
{
if (consts.Keys.Contains(node.ToString()))
{
return(consts[node.ToString()]);
}
return(base.VisitIdentifierExpr(node));
}
public override Expr VisitIdentifierExpr(IdentifierExpr node)
{
var ie = (IdentifierExpr)base.VisitIdentifierExpr(node);
// Need to fix up the name, since IdentifierExpr's equality also checks the name
ie.Name = ie.Decl.TypedIdent.Name;
return(ie);
}
public override Expr VisitIdentifierExpr(IdentifierExpr node)
{
if (!globals.Contains(node.Name))
{
usedVars.Add(node.Name);
}
return(node);
}
public override Expr VisitIdentifierExpr(IdentifierExpr node)
{
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result <Expr>() != null);
Expr /*?*/ e = subst(cce.NonNull(node.Decl));
return(e == null?base.VisitIdentifierExpr(node) : e);
}
public override Expr VisitIdentifierExpr(IdentifierExpr node)
{
if (node.Decl == _toSearch)
{
Success = true;
}
return(base.VisitIdentifierExpr(node));
}
public override Expr VisitIdentifierExpr(IdentifierExpr node)
{
if (AllMaps.Contains(node.Name))
{
return(Expr.Ident(U));
}
return(node);
}
public override Expr VisitIdentifierExpr(IdentifierExpr node)
{
if (GetReplacementVariable(node, out var variable))
{
return(new IdentifierExpr(variable.tok, variable));
}
return(base.VisitIdentifierExpr(node));
}
public ClassDefinitionStmt(IdentifierExpr name,
IEnumerable <VarDefinitionStmt> members,
IEnumerable <FunctionExpr> functions)
{
_name = name;
_members = members.ToArray();
_functions = functions.ToArray();
}
public override Expr VisitIdentifierExpr(IdentifierExpr node)
{
if (node.Decl != null)
{
node.Decl = this.VisitVariable(node.Decl);
}
return(node);
}
protected Tuple <Variable, IdentifierExpr> GetBoundVarAndIdExpr(string name, Microsoft.Boogie.Type type)
{
var typeIdent = new TypedIdent(Token.NoToken, name, type);
var v = new BoundVariable(Token.NoToken, typeIdent);
var id = new IdentifierExpr(Token.NoToken, v, /*immutable=*/ true);
return(new Tuple <Variable, IdentifierExpr>(v, id));
}
public void CachedHashCodeIdentifierExpr()
{
var id = new IdentifierExpr(Token.NoToken, "foo", BasicType.Bool, /*immutable=*/true);
Assert.AreEqual(id.ComputeHashCode(), id.GetHashCode());
var variable = new BoundVariable(Token.NoToken, new TypedIdent(Token.NoToken, "foo2", BasicType.Int));
var id2 = new IdentifierExpr(Token.NoToken, variable, /*immutable=*/true);
Assert.AreEqual(id2.ComputeHashCode(), id2.GetHashCode());
}
public void FunctionNamePropertyReturnsPassedName()
{
var name = new IdentifierExpr(RandomGenerator.String());
var arguments = new Expression[] { new ConstantExpr(RandomGenerator.Int()), new ConstantExpr(RandomGenerator.Int()) };
var target = new FunctionCallExpr(name, arguments);
Assert.AreSame(name.Name, target.FunctionName.Name);
}
public void SimpleIdentifierExprs() {
var variable = new GlobalVariable(Token.NoToken, new TypedIdent(Token.NoToken, "foo", Microsoft.Boogie.Type.GetBvType(8)));
var idVar = new IdentifierExpr(Token.NoToken, variable);
var idVar2 = new IdentifierExpr(Token.NoToken, variable);
Assert.AreNotSame(idVar, idVar2); // These are different references
Assert.IsTrue(idVar.Equals(idVar2)); // These are "structurally equal"
Assert.AreEqual(idVar.GetHashCode(), idVar2.GetHashCode()); // If the .Equals() is true then hash codes must be the same
}
public static void Predicate(Program p,
Func<Procedure, bool> useProcedurePredicates = null,
UniformityAnalyser uni = null)
{
useProcedurePredicates = useProcedurePredicates ?? (proc => false);
if (uni != null) {
var oldUPP = useProcedurePredicates;
useProcedurePredicates = proc => oldUPP(proc) && !uni.IsUniform(proc.Name);
}
foreach (var decl in p.TopLevelDeclarations.ToList()) {
if (decl is Procedure || decl is Implementation) {
var proc = decl as Procedure;
Implementation impl = null;
if (proc == null) {
impl = (Implementation)decl;
proc = impl.Proc;
}
bool upp = useProcedurePredicates(proc);
if (upp) {
var dwf = (DeclWithFormals)decl;
var fpVar = new Formal(Token.NoToken,
new TypedIdent(Token.NoToken, "_P",
Microsoft.Boogie.Type.Bool),
/*incoming=*/true);
dwf.InParams = new List<Variable>(
(new Variable[] {fpVar}.Concat(dwf.InParams.Cast<Variable>()))
.ToArray());
if (impl == null) {
var fpIdentifierExpr = new IdentifierExpr(Token.NoToken, fpVar);
foreach (Requires r in proc.Requires) {
new EnabledReplacementVisitor(fpIdentifierExpr).VisitExpr(r.Condition);
if (!QKeyValue.FindBoolAttribute(r.Attributes, "do_not_predicate")) {
r.Condition = Expr.Imp(fpIdentifierExpr, r.Condition);
}
}
foreach (Ensures e in proc.Ensures) {
new EnabledReplacementVisitor(new IdentifierExpr(Token.NoToken, fpVar)).VisitExpr(e.Condition);
if (!QKeyValue.FindBoolAttribute(e.Attributes, "do_not_predicate")) {
e.Condition = Expr.Imp(fpIdentifierExpr, e.Condition);
}
}
}
}
if (impl != null) {
try {
new SmartBlockPredicator(p, impl, useProcedurePredicates, uni).PredicateImplementation();
} catch (Program.IrreducibleLoopException) { }
}
}
}
}
public void ReturnTypePropertyReturnsPassedReturnType()
{
var name = new IdentifierExpr(RandomGenerator.String());
var arguments = new VarDefinitionStmt[0];
var body = new ConstantExpr(RandomGenerator.Int());
var returnType = new IdentifierExpr(RandomGenerator.String());
var target = new LambdaDefinitionExpr(name, arguments, body, returnType);
Assert.AreSame(returnType, target.ReturnType);
}
public void BodyPropertyReturnsPassedBody2()
{
var name = new IdentifierExpr(RandomGenerator.String());
var arguments = new VarDefinitionStmt[0];
var body = new ScopeBlockStmt(new [] { new NoOpStatement()});
var returnType = new IdentifierExpr(RandomGenerator.String());
var target = new FunctionDefinitionExpr(name, arguments, body, returnType);
Assert.AreSame(body, target.Body);
}
public void ArgumentsPropertyReturnsPassedArguments()
{
var name = new IdentifierExpr(RandomGenerator.String());
var arguments = new VarDefinitionStmt[0];
var body = new NoOpStatement();
var returnType = new IdentifierExpr(RandomGenerator.String());
var target = new FunctionDefinitionExpr(name, arguments, body, returnType);
Assert.AreSame(arguments, target.Arguments);
}
public void AcceptMethodCallsVisitOnVisitorWithThis()
{
var name = new IdentifierExpr(RandomGenerator.String());
var arguments = new Expression[] { new ConstantExpr(RandomGenerator.Int()), new ConstantExpr(RandomGenerator.Int()) };
var target = new FunctionCallExpr(name, arguments);
var visitor = new Mock<IExpressionVisitor<string, int>>();
target.Accept(visitor.Object, 0);
visitor.Verify(x => x.Visit(target, 0), Times.Once);
}
public void AcceptMethodCallsOnlyVisitOnVisitorWithThisAndNoOtherVisitMethods()
{
var name = new IdentifierExpr(RandomGenerator.String());
var arguments = new Expression[] { new ConstantExpr(RandomGenerator.Int()), new ConstantExpr(RandomGenerator.Int()) };
var target = new FunctionCallExpr(name, arguments);
// throw exception is any other methods called other than the PlusExpr overload.
var visitor = new Mock<IExpressionVisitor<string, int>>(MockBehavior.Strict);
visitor.Setup(x => x.Visit(target, 123)).Returns("");
target.Accept(visitor.Object, 123);
}
private List<VarDefinitionStmt> ParseParameterList(Parser parser)
{
var parameters = new List<VarDefinitionStmt>();
if (parser.Peek().Type == "RIGHTPAREN")
return parameters;
while (true)
{
var name = parser.ParseExpression(0);
if(!(name is IdentifierExpr))
throw new ParseException("Expected parameter name");
Expression type = null;
if (parser.ConsumeOptional("COLON"))
{
type = parser.ParseExpression(0);
if (!(type is IdentifierExpr))
throw new ParseException("Expected parameter type");
}
else
{
type = new IdentifierExpr("dynamic");
}
parameters.Add(new VarDefinitionStmt((IdentifierExpr)name, (IdentifierExpr)type, false, null));
if (parser.Peek().Type == "RIGHTPAREN")
break;
parser.Consume("COMMA");
}
return parameters;
}
public void IdentifierExprDecl()
{
var id = new IdentifierExpr(Token.NoToken, "foo", BasicType.Bool, /*immutable=*/true);
Assert.IsTrue(id.Immutable);
var typedIdent = new TypedIdent(Token.NoToken, "foo2", BasicType.Bool);
id.Decl = new GlobalVariable(Token.NoToken, typedIdent);
}
public void IdentifierExprName()
{
var id = new IdentifierExpr(Token.NoToken, "foo", BasicType.Bool, /*immutable=*/true);
Assert.IsTrue(id.Immutable);
id.Name = "foo2";
}
/// <summary>
/// Before calling TrExpr(expr), the caller must have spilled the let variables declared in "expr".
/// </summary>
void TrExpr(Expression expr, TextWriter wr, bool inLetExprBody)
{
Contract.Requires(expr != null);
if (expr is LiteralExpr) {
LiteralExpr e = (LiteralExpr)expr;
if (e is StaticReceiverExpr) {
wr.Write(TypeName(e.Type, wr));
} else if (e.Value == null) {
wr.Write("({0})null", TypeName(e.Type, wr));
} else if (e.Value is bool) {
wr.Write((bool)e.Value ? "true" : "false");
} else if (e is CharLiteralExpr) {
wr.Write("'{0}'", (string)e.Value);
} else if (e is StringLiteralExpr) {
var str = (StringLiteralExpr)e;
wr.Write("{0}<char>.FromString({1}\"{2}\")", DafnySeqClass, str.IsVerbatim ? "@" : "", (string)e.Value);
} else if (AsNativeType(e.Type) != null) {
wr.Write((BigInteger)e.Value + AsNativeType(e.Type).Suffix);
} else if (e.Value is BigInteger) {
BigInteger i = (BigInteger)e.Value;
if (new BigInteger(int.MinValue) <= i && i <= new BigInteger(int.MaxValue)) {
wr.Write("new BigInteger({0})", i);
} else {
wr.Write("BigInteger.Parse(\"{0}\")", i);
}
} else if (e.Value is Basetypes.BigDec) {
var n = (Basetypes.BigDec)e.Value;
if (0 <= n.Exponent) {
wr.Write("new Dafny.BigRational(new BigInteger({0}", n.Mantissa);
for (int i = 0; i < n.Exponent; i++) {
wr.Write("0");
}
wr.Write("), BigInteger.One)");
} else {
wr.Write("new Dafny.BigRational(new BigInteger({0}), new BigInteger(1", n.Mantissa);
for (int i = n.Exponent; i < 0; i++) {
wr.Write("0");
}
wr.Write("))");
}
} else {
Contract.Assert(false); throw new cce.UnreachableException(); // unexpected literal
}
} else if (expr is ThisExpr) {
wr.Write(enclosingMethod != null && enclosingMethod.IsTailRecursive ? "_this" : "this");
} else if (expr is IdentifierExpr) {
var e = (IdentifierExpr)expr;
if (e.Var is Formal && inLetExprBody && !((Formal)e.Var).InParam) {
// out param in letExpr body, need to copy it to a temp since
// letExpr body is translated to an anonymous function that doesn't
// allow out parameters
var name = string.Format("_pat_let_tv{0}", GetUniqueAstNumber(e));
wr.Write("@" + name);
copyInstrWriter.Append("var @" + name + "= @" + e.Var.CompileName + ";\n");
} else {
wr.Write("@" + e.Var.CompileName);
}
} else if (expr is SetDisplayExpr) {
var e = (SetDisplayExpr)expr;
var elType = e.Type.AsSetType.Arg;
wr.Write("{0}<{1}>.FromElements", DafnySetClass, TypeName(elType, wr));
TrExprList(e.Elements, wr, inLetExprBody);
} else if (expr is MultiSetDisplayExpr) {
var e = (MultiSetDisplayExpr)expr;
var elType = e.Type.AsMultiSetType.Arg;
wr.Write("{0}<{1}>.FromElements", DafnyMultiSetClass, TypeName(elType, wr));
TrExprList(e.Elements, wr, inLetExprBody);
} else if (expr is SeqDisplayExpr) {
var e = (SeqDisplayExpr)expr;
var elType = e.Type.AsSeqType.Arg;
wr.Write("{0}<{1}>.FromElements", DafnySeqClass, TypeName(elType, wr));
TrExprList(e.Elements, wr, inLetExprBody);
} else if (expr is MapDisplayExpr) {
MapDisplayExpr e = (MapDisplayExpr)expr;
wr.Write("{0}.FromElements", TypeName(e.Type, wr));
TrExprPairList(e.Elements, wr, inLetExprBody);
} else if (expr is MemberSelectExpr) {
MemberSelectExpr e = (MemberSelectExpr)expr;
SpecialField sf = e.Member as SpecialField;
if (sf != null) {
wr.Write(sf.PreString);
TrParenExpr(e.Obj, wr, inLetExprBody);
wr.Write(".@{0}", sf.CompiledName);
wr.Write(sf.PostString);
} else {
TrExpr(e.Obj, wr, inLetExprBody);
wr.Write(".@{0}", e.Member.CompileName);
}
} else if (expr is SeqSelectExpr) {
SeqSelectExpr e = (SeqSelectExpr)expr;
Contract.Assert(e.Seq.Type != null);
if (e.Seq.Type.IsArrayType) {
if (e.SelectOne) {
Contract.Assert(e.E0 != null && e.E1 == null);
TrParenExpr(e.Seq, wr, inLetExprBody);
wr.Write("[(int)");
TrParenExpr(e.E0, wr, inLetExprBody);
wr.Write("]");
} else {
TrParenExpr("Dafny.Helpers.SeqFromArray", e.Seq, wr, inLetExprBody);
if (e.E1 != null) {
TrParenExpr(".Take", e.E1, wr, inLetExprBody);
}
if (e.E0 != null) {
TrParenExpr(".Drop", e.E0, wr, inLetExprBody);
}
}
} else if (e.SelectOne) {
Contract.Assert(e.E0 != null && e.E1 == null);
TrParenExpr(e.Seq, wr, inLetExprBody);
TrParenExpr(".Select", e.E0, wr, inLetExprBody);
} else {
TrParenExpr(e.Seq, wr, inLetExprBody);
if (e.E1 != null) {
TrParenExpr(".Take", e.E1, wr, inLetExprBody);
}
if (e.E0 != null) {
TrParenExpr(".Drop", e.E0, wr, inLetExprBody);
}
}
} else if (expr is MultiSetFormingExpr) {
var e = (MultiSetFormingExpr)expr;
wr.Write("{0}<{1}>", DafnyMultiSetClass, TypeName(e.E.Type.AsCollectionType.Arg, wr));
var eeType = e.E.Type.NormalizeExpand();
if (eeType is SeqType) {
TrParenExpr(".FromSeq", e.E, wr, inLetExprBody);
} else if (eeType is SetType) {
TrParenExpr(".FromSet", e.E, wr, inLetExprBody);
} else {
Contract.Assert(false); throw new cce.UnreachableException();
}
} else if (expr is MultiSelectExpr) {
MultiSelectExpr e = (MultiSelectExpr)expr;
TrParenExpr(e.Array, wr, inLetExprBody);
string prefix = "[";
foreach (Expression idx in e.Indices) {
wr.Write("{0}(int)", prefix);
TrParenExpr(idx, wr, inLetExprBody);
prefix = ", ";
}
wr.Write("]");
} else if (expr is SeqUpdateExpr) {
SeqUpdateExpr e = (SeqUpdateExpr)expr;
if (e.ResolvedUpdateExpr != null)
{
TrExpr(e.ResolvedUpdateExpr, wr, inLetExprBody);
}
else
{
TrParenExpr(e.Seq, wr, inLetExprBody);
wr.Write(".Update(");
TrExpr(e.Index, wr, inLetExprBody);
wr.Write(", ");
TrExpr(e.Value, wr, inLetExprBody);
wr.Write(")");
}
} else if (expr is FunctionCallExpr) {
FunctionCallExpr e = (FunctionCallExpr)expr;
CompileFunctionCallExpr(e, wr, wr, inLetExprBody, TrExpr);
} else if (expr is ApplyExpr) {
var e = expr as ApplyExpr;
wr.Write("Dafny.Helpers.Id<");
wr.Write(TypeName(e.Function.Type, wr));
wr.Write(">(");
TrExpr(e.Function, wr, inLetExprBody);
wr.Write(")");
TrExprList(e.Args, wr, inLetExprBody);
} else if (expr is DatatypeValue) {
DatatypeValue dtv = (DatatypeValue)expr;
Contract.Assert(dtv.Ctor != null); // since dtv has been successfully resolved
var typeParams = dtv.InferredTypeArgs.Count == 0 ? "" : string.Format("<{0}>", TypeNames(dtv.InferredTypeArgs, wr));
wr.Write("new @{0}{1}(", DtName(dtv.Ctor.EnclosingDatatype), typeParams);
if (!dtv.IsCoCall) {
// For an ordinary constructor (that is, one that does not guard any co-recursive calls), generate:
// new Dt_Cons<T>( args )
wr.Write("new {0}(", DtCtorName(dtv.Ctor, dtv.InferredTypeArgs, wr));
string sep = "";
for (int i = 0; i < dtv.Arguments.Count; i++) {
Formal formal = dtv.Ctor.Formals[i];
if (!formal.IsGhost) {
wr.Write(sep);
TrExpr(dtv.Arguments[i], wr, inLetExprBody);
sep = ", ";
}
}
wr.Write(")");
} else {
// In the case of a co-recursive call, generate:
// new Dt__Lazy<T>( new Dt__Lazy<T>.ComputerComputer( LAMBDA )() )
// where LAMBDA is:
// () => { var someLocals = eagerlyEvaluatedArguments;
// return () => { return Dt_Cons<T>( ...args...using someLocals and including function calls to be evaluated lazily... ); };
// }
wr.Write("new {0}__Lazy{1}", dtv.DatatypeName, typeParams);
wr.Write("(new {0}__Lazy{1}.ComputerComputer(() => {{ ", dtv.DatatypeName, typeParams);
// locals
string args = "";
string sep = "";
for (int i = 0; i < dtv.Arguments.Count; i++) {
Formal formal = dtv.Ctor.Formals[i];
if (!formal.IsGhost) {
Expression actual = dtv.Arguments[i].Resolved;
string arg;
var fce = actual as FunctionCallExpr;
if (fce == null || fce.CoCall != FunctionCallExpr.CoCallResolution.Yes) {
string varName = idGenerator.FreshId("_ac");
arg = varName;
wr.Write("var {0} = ", varName);
TrExpr(actual, wr, inLetExprBody);
wr.Write("; ");
} else {
var sw = new StringWriter();
CompileFunctionCallExpr(fce, sw, wr, inLetExprBody, (exp, wrr, inLetExpr) => {
string varName = idGenerator.FreshId("_ac");
sw.Write(varName);
wrr.Write("var {0} = ", varName);
TrExpr(exp, wrr, inLetExpr);
wrr.Write("; ");
});
arg = sw.ToString();
}
args += sep + arg;
sep = ", ";
}
}
wr.Write("return () => { return ");
wr.Write("new {0}({1}", DtCtorName(dtv.Ctor, dtv.InferredTypeArgs, wr), args);
wr.Write("); }; })())");
}
wr.Write(")");
} else if (expr is OldExpr) {
Contract.Assert(false); throw new cce.UnreachableException(); // 'old' is always a ghost (right?)
} else if (expr is UnaryOpExpr) {
var e = (UnaryOpExpr)expr;
switch (e.Op) {
case UnaryOpExpr.Opcode.Not:
wr.Write("!");
TrParenExpr(e.E, wr, inLetExprBody);
break;
case UnaryOpExpr.Opcode.Cardinality:
wr.Write("new BigInteger(");
TrParenExpr(e.E, wr, inLetExprBody);
wr.Write(".Length)");
break;
default:
Contract.Assert(false); throw new cce.UnreachableException(); // unexpected unary expression
}
} else if (expr is ConversionExpr) {
var e = (ConversionExpr)expr;
var fromInt = e.E.Type.IsNumericBased(Type.NumericPersuation.Int);
Contract.Assert(fromInt || e.E.Type.IsNumericBased(Type.NumericPersuation.Real));
var toInt = e.ToType.IsNumericBased(Type.NumericPersuation.Int);
Contract.Assert(toInt || e.ToType.IsNumericBased(Type.NumericPersuation.Real));
Action fromIntAsBigInteger = () => {
Contract.Assert(fromInt);
if (AsNativeType(e.E.Type) != null) {
wr.Write("new BigInteger");
}
TrParenExpr(e.E, wr, inLetExprBody);
};
Action toIntCast = () => {
Contract.Assert(toInt);
if (AsNativeType(e.ToType) != null) {
wr.Write("(" + AsNativeType(e.ToType).Name + ")");
}
};
if (fromInt && !toInt) {
// int -> real
wr.Write("new Dafny.BigRational(");
fromIntAsBigInteger();
wr.Write(", BigInteger.One)");
} else if (!fromInt && toInt) {
// real -> int
toIntCast();
TrParenExpr(e.E, wr, inLetExprBody);
wr.Write(".ToBigInteger()");
} else if (AsNativeType(e.ToType) != null) {
toIntCast();
LiteralExpr lit = e.E.Resolved as LiteralExpr;
UnaryOpExpr u = e.E.Resolved as UnaryOpExpr;
MemberSelectExpr m = e.E.Resolved as MemberSelectExpr;
if (lit != null && lit.Value is BigInteger) {
// Optimize constant to avoid intermediate BigInteger
wr.Write("(" + (BigInteger)lit.Value + AsNativeType(e.ToType).Suffix + ")");
} else if ((u != null && u.Op == UnaryOpExpr.Opcode.Cardinality) || (m != null && m.MemberName == "Length" && m.Obj.Type.IsArrayType)) {
// Optimize .Length to avoid intermediate BigInteger
TrParenExpr((u != null) ? u.E : m.Obj, wr, inLetExprBody);
if (AsNativeType(e.ToType).UpperBound <= new BigInteger(0x80000000U)) {
wr.Write(".Length");
} else {
wr.Write(".LongLength");
}
} else {
TrParenExpr(e.E, wr, inLetExprBody);
}
} else if (e.ToType.IsIntegerType && AsNativeType(e.E.Type) != null) {
fromIntAsBigInteger();
} else {
Contract.Assert(fromInt == toInt);
Contract.Assert(AsNativeType(e.ToType) == null);
Contract.Assert(AsNativeType(e.E.Type) == null);
TrParenExpr(e.E, wr, inLetExprBody);
}
} else if (expr is BinaryExpr) {
BinaryExpr e = (BinaryExpr)expr;
string opString = null;
string preOpString = "";
string callString = null;
switch (e.ResolvedOp) {
case BinaryExpr.ResolvedOpcode.Iff:
opString = "=="; break;
case BinaryExpr.ResolvedOpcode.Imp:
preOpString = "!"; opString = "||"; break;
case BinaryExpr.ResolvedOpcode.Or:
opString = "||"; break;
case BinaryExpr.ResolvedOpcode.And:
opString = "&&"; break;
case BinaryExpr.ResolvedOpcode.EqCommon: {
if (e.E0.Type.IsRefType) {
// Dafny's type rules are slightly different C#, so we may need a cast here.
// For example, Dafny allows x==y if x:array<T> and y:array<int> and T is some
// type parameter.
opString = "== (object)";
} else if (e.E0.Type.IsDatatype || e.E0.Type.IsTypeParameter || e.E0.Type.SupportsEquality) {
callString = "Equals";
} else {
opString = "==";
}
break;
}
case BinaryExpr.ResolvedOpcode.NeqCommon: {
if (e.E0.Type.IsRefType) {
// Dafny's type rules are slightly different C#, so we may need a cast here.
// For example, Dafny allows x==y if x:array<T> and y:array<int> and T is some
// type parameter.
opString = "!= (object)";
} else if (e.E0.Type.IsDatatype || e.E0.Type.IsTypeParameter || e.E0.Type.SupportsEquality) {
preOpString = "!";
callString = "Equals";
} else {
opString = "!=";
}
break;
}
case BinaryExpr.ResolvedOpcode.Lt:
case BinaryExpr.ResolvedOpcode.LtChar:
opString = "<"; break;
case BinaryExpr.ResolvedOpcode.Le:
case BinaryExpr.ResolvedOpcode.LeChar:
opString = "<="; break;
case BinaryExpr.ResolvedOpcode.Ge:
case BinaryExpr.ResolvedOpcode.GeChar:
opString = ">="; break;
case BinaryExpr.ResolvedOpcode.Gt:
case BinaryExpr.ResolvedOpcode.GtChar:
opString = ">"; break;
case BinaryExpr.ResolvedOpcode.Add:
opString = "+"; break;
case BinaryExpr.ResolvedOpcode.Sub:
opString = "-"; break;
case BinaryExpr.ResolvedOpcode.Mul:
opString = "*"; break;
case BinaryExpr.ResolvedOpcode.Div:
if (expr.Type.IsIntegerType || (AsNativeType(expr.Type) != null && AsNativeType(expr.Type).LowerBound < BigInteger.Zero)) {
string suffix = AsNativeType(expr.Type) != null ? ("_" + AsNativeType(expr.Type).Name) : "";
wr.Write("Dafny.Helpers.EuclideanDivision" + suffix + "(");
TrParenExpr(e.E0, wr, inLetExprBody);
wr.Write(", ");
TrExpr(e.E1, wr, inLetExprBody);
wr.Write(")");
} else {
opString = "/"; // for reals
}
break;
case BinaryExpr.ResolvedOpcode.Mod:
if (expr.Type.IsIntegerType || (AsNativeType(expr.Type) != null && AsNativeType(expr.Type).LowerBound < BigInteger.Zero)) {
string suffix = AsNativeType(expr.Type) != null ? ("_" + AsNativeType(expr.Type).Name) : "";
wr.Write("Dafny.Helpers.EuclideanModulus" + suffix + "(");
TrParenExpr(e.E0, wr, inLetExprBody);
wr.Write(", ");
TrExpr(e.E1, wr, inLetExprBody);
wr.Write(")");
} else {
opString = "%"; // for reals
}
break;
case BinaryExpr.ResolvedOpcode.SetEq:
case BinaryExpr.ResolvedOpcode.MultiSetEq:
case BinaryExpr.ResolvedOpcode.SeqEq:
case BinaryExpr.ResolvedOpcode.MapEq:
callString = "Equals"; break;
case BinaryExpr.ResolvedOpcode.SetNeq:
case BinaryExpr.ResolvedOpcode.MultiSetNeq:
case BinaryExpr.ResolvedOpcode.SeqNeq:
case BinaryExpr.ResolvedOpcode.MapNeq:
preOpString = "!"; callString = "Equals"; break;
case BinaryExpr.ResolvedOpcode.ProperSubset:
case BinaryExpr.ResolvedOpcode.ProperMultiSubset:
callString = "IsProperSubsetOf"; break;
case BinaryExpr.ResolvedOpcode.Subset:
case BinaryExpr.ResolvedOpcode.MultiSubset:
callString = "IsSubsetOf"; break;
case BinaryExpr.ResolvedOpcode.Superset:
case BinaryExpr.ResolvedOpcode.MultiSuperset:
callString = "IsSupersetOf"; break;
case BinaryExpr.ResolvedOpcode.ProperSuperset:
case BinaryExpr.ResolvedOpcode.ProperMultiSuperset:
callString = "IsProperSupersetOf"; break;
case BinaryExpr.ResolvedOpcode.Disjoint:
case BinaryExpr.ResolvedOpcode.MultiSetDisjoint:
case BinaryExpr.ResolvedOpcode.MapDisjoint:
callString = "IsDisjointFrom"; break;
case BinaryExpr.ResolvedOpcode.InSet:
case BinaryExpr.ResolvedOpcode.InMultiSet:
case BinaryExpr.ResolvedOpcode.InMap:
TrParenExpr(e.E1, wr, inLetExprBody);
wr.Write(".Contains(");
TrExpr(e.E0, wr, inLetExprBody);
wr.Write(")");
break;
case BinaryExpr.ResolvedOpcode.NotInSet:
case BinaryExpr.ResolvedOpcode.NotInMultiSet:
case BinaryExpr.ResolvedOpcode.NotInMap:
wr.Write("!");
TrParenExpr(e.E1, wr, inLetExprBody);
wr.Write(".Contains(");
TrExpr(e.E0, wr, inLetExprBody);
wr.Write(")");
break;
case BinaryExpr.ResolvedOpcode.Union:
case BinaryExpr.ResolvedOpcode.MultiSetUnion:
callString = "Union"; break;
case BinaryExpr.ResolvedOpcode.Intersection:
case BinaryExpr.ResolvedOpcode.MultiSetIntersection:
callString = "Intersect"; break;
case BinaryExpr.ResolvedOpcode.SetDifference:
case BinaryExpr.ResolvedOpcode.MultiSetDifference:
callString = "Difference"; break;
case BinaryExpr.ResolvedOpcode.ProperPrefix:
callString = "IsProperPrefixOf"; break;
case BinaryExpr.ResolvedOpcode.Prefix:
callString = "IsPrefixOf"; break;
case BinaryExpr.ResolvedOpcode.Concat:
callString = "Concat"; break;
case BinaryExpr.ResolvedOpcode.InSeq:
TrParenExpr(e.E1, wr, inLetExprBody);
wr.Write(".Contains(");
TrExpr(e.E0, wr, inLetExprBody);
wr.Write(")");
break;
case BinaryExpr.ResolvedOpcode.NotInSeq:
wr.Write("!");
TrParenExpr(e.E1, wr, inLetExprBody);
wr.Write(".Contains(");
TrExpr(e.E0, wr, inLetExprBody);
wr.Write(")");
break;
default:
Contract.Assert(false); throw new cce.UnreachableException(); // unexpected binary expression
}
if (opString != null) {
NativeType nativeType = AsNativeType(e.Type);
bool needsCast = nativeType != null && nativeType.NeedsCastAfterArithmetic;
if (needsCast) {
wr.Write("(" + nativeType.Name + ")(");
}
wr.Write(preOpString);
TrParenExpr(e.E0, wr, inLetExprBody);
wr.Write(" {0} ", opString);
TrParenExpr(e.E1, wr, inLetExprBody);
if (needsCast) {
wr.Write(")");
}
} else if (callString != null) {
wr.Write(preOpString);
TrParenExpr(e.E0, wr, inLetExprBody);
wr.Write(".@{0}(", callString);
TrExpr(e.E1, wr, inLetExprBody);
wr.Write(")");
}
} else if (expr is TernaryExpr) {
Contract.Assume(false); // currently, none of the ternary expressions is compilable
} else if (expr is LetExpr) {
var e = (LetExpr)expr;
if (e.Exact) {
// The Dafny "let" expression
// var Pattern(x,y) := G; E
// is translated into C# as:
// LamLet(G, tmp =>
// LamLet(dtorX(tmp), x =>
// LamLet(dtorY(tmp), y => E)))
Contract.Assert(e.LHSs.Count == e.RHSs.Count); // checked by resolution
var neededCloseParens = 0;
for (int i = 0; i < e.LHSs.Count; i++) {
var lhs = e.LHSs[i];
if (Contract.Exists(lhs.Vars, bv => !bv.IsGhost)) {
var rhsName = string.Format("_pat_let{0}_{1}", GetUniqueAstNumber(e), i);
wr.Write("Dafny.Helpers.Let<");
wr.Write(TypeName(e.RHSs[i].Type, wr) + "," + TypeName(e.Body.Type, wr));
wr.Write(">(");
TrExpr(e.RHSs[i], wr, inLetExprBody);
wr.Write(", " + rhsName + " => ");
neededCloseParens++;
var c = TrCasePattern(lhs, rhsName, e.Body.Type, wr);
Contract.Assert(c != 0); // we already checked that there's at least one non-ghost
neededCloseParens += c;
}
}
TrExpr(e.Body, wr, true);
for (int i = 0; i < neededCloseParens; i++) {
wr.Write(")");
}
} else if (e.BoundVars.All(bv => bv.IsGhost)) {
// The Dafny "let" expression
// ghost var x,y :| Constraint; E
// is compiled just like E is, because the resolver has already checked that x,y (or other ghost variables, for that matter) don't
// occur in E (moreover, the verifier has checked that values for x,y satisfying Constraint exist).
TrExpr(e.Body, wr, inLetExprBody);
} else {
// The Dafny "let" expression
// var x,y :| Constraint; E
// is translated into C# as:
// LamLet(0, dummy => { // the only purpose of this construction here is to allow us to add some code inside an expression in C#
// var x,y;
// // Embark on computation that fills in x,y according to Constraint; the computation stops when the first
// // such value is found, but since the verifier checks that x,y follows uniquely from Constraint, this is
// // not a source of nondeterminancy.
// return E;
// })
Contract.Assert(e.RHSs.Count == 1); // checked by resolution
if (e.Constraint_MissingBounds != null) {
foreach (var bv in e.Constraint_MissingBounds) {
Error("this let-such-that expression is too advanced for the current compiler; Dafny's heuristics cannot find any bound for variable '{0}' (line {1})", wr, bv.Name, e.tok.line);
}
} else {
wr.Write("Dafny.Helpers.Let<int," + TypeName(e.Body.Type, wr) + ">(0, _let_dummy_" + GetUniqueAstNumber(e) + " => {");
foreach (var bv in e.BoundVars) {
wr.Write("{0} @{1}", TypeName(bv.Type, wr), bv.CompileName);
wr.WriteLine(" = {0};", DefaultValue(bv.Type, wr));
}
TrAssignSuchThat(0, new List<IVariable>(e.BoundVars).ConvertAll(bv => (IVariable)bv), e.RHSs[0], e.Constraint_Bounds, e.tok.line, wr, inLetExprBody);
wr.Write(" return ");
TrExpr(e.Body, wr, true);
wr.Write("; })");
}
}
} else if (expr is MatchExpr) {
var e = (MatchExpr)expr;
// new Dafny.Helpers.Function<SourceType, TargetType>(delegate (SourceType _source) {
// if (source.is_Ctor0) {
// FormalType f0 = ((Dt_Ctor0)source._D).a0;
// ...
// return Body0;
// } else if (...) {
// ...
// } else if (true) {
// ...
// }
// }(src)
string source = idGenerator.FreshId("_source");
wr.Write("new Dafny.Helpers.Function<{0}, {1}>(delegate ({0} {2}) {{ ", TypeName(e.Source.Type, wr), TypeName(e.Type, wr), source);
if (e.Cases.Count == 0) {
// the verifier would have proved we never get here; still, we need some code that will compile
wr.Write("throw new System.Exception();");
} else {
int i = 0;
var sourceType = (UserDefinedType)e.Source.Type.NormalizeExpand();
foreach (MatchCaseExpr mc in e.Cases) {
MatchCasePrelude(source, sourceType, cce.NonNull(mc.Ctor), mc.Arguments, i, e.Cases.Count, 0, wr);
wr.Write("return ");
TrExpr(mc.Body, wr, inLetExprBody);
wr.Write("; ");
i++;
}
wr.Write("}");
}
// We end with applying the source expression to the delegate we just built
wr.Write("})(");
TrExpr(e.Source, wr, inLetExprBody);
wr.Write(")");
} else if (expr is QuantifierExpr) {
var e = (QuantifierExpr)expr;
// Compilation does not check whether a quantifier was split.
Contract.Assert(e.Bounds != null); // for non-ghost quantifiers, the resolver would have insisted on finding bounds
var n = e.BoundVars.Count;
Contract.Assert(e.Bounds.Count == n);
for (int i = 0; i < n; i++) {
var bound = e.Bounds[i];
var bv = e.BoundVars[i];
// emit: Dafny.Helpers.QuantX(boundsInformation, isForall, bv => body)
if (bound is ComprehensionExpr.BoolBoundedPool) {
wr.Write("Dafny.Helpers.QuantBool(");
} else if (bound is ComprehensionExpr.CharBoundedPool) {
wr.Write("Dafny.Helpers.QuantChar(");
} else if (bound is ComprehensionExpr.IntBoundedPool) {
var b = (ComprehensionExpr.IntBoundedPool)bound;
wr.Write("Dafny.Helpers.QuantInt(");
TrExpr(b.LowerBound, wr, inLetExprBody);
wr.Write(", ");
TrExpr(b.UpperBound, wr, inLetExprBody);
wr.Write(", ");
} else if (bound is ComprehensionExpr.SetBoundedPool) {
var b = (ComprehensionExpr.SetBoundedPool)bound;
wr.Write("Dafny.Helpers.QuantSet(");
TrExpr(b.Set, wr, inLetExprBody);
wr.Write(", ");
} else if (bound is ComprehensionExpr.MapBoundedPool) {
var b = (ComprehensionExpr.MapBoundedPool)bound;
wr.Write("Dafny.Helpers.QuantMap(");
TrExpr(b.Map, wr, inLetExprBody);
wr.Write(", ");
} else if (bound is ComprehensionExpr.SeqBoundedPool) {
var b = (ComprehensionExpr.SeqBoundedPool)bound;
wr.Write("Dafny.Helpers.QuantSeq(");
TrExpr(b.Seq, wr, inLetExprBody);
wr.Write(", ");
} else if (bound is ComprehensionExpr.DatatypeBoundedPool) {
var b = (ComprehensionExpr.DatatypeBoundedPool)bound;
wr.Write("Dafny.Helpers.QuantDatatype(");
wr.Write("{0}.AllSingletonConstructors, ", DtName(b.Decl));
} else {
Contract.Assert(false); throw new cce.UnreachableException(); // unexpected BoundedPool type
}
wr.Write("{0}, ", expr is ForallExpr ? "true" : "false");
wr.Write("@{0} => ", bv.CompileName);
}
TrExpr(e.LogicalBody(true), wr, inLetExprBody);
for (int i = 0; i < n; i++) {
wr.Write(")");
}
} else if (expr is SetComprehension) {
var e = (SetComprehension)expr;
// For "set i,j,k,l | R(i,j,k,l) :: Term(i,j,k,l)" where the term has type "G", emit something like:
// ((ComprehensionDelegate<G>)delegate() {
// var _coll = new List<G>();
// foreach (L l in sq.Elements) {
// foreach (K k in st.Elements) {
// for (BigInteger j = Lo; j < Hi; j++) {
// for (bool i in Helper.AllBooleans) {
// if (R(i,j,k,l)) {
// _coll.Add(Term(i,j,k,l));
// }
// }
// }
// }
// }
// return Dafny.Set<G>.FromCollection(_coll);
// })()
Contract.Assert(e.Bounds != null); // the resolver would have insisted on finding bounds
var typeName = TypeName(e.Type.AsSetType.Arg, wr);
var collection_name = idGenerator.FreshId("_coll");
wr.Write("((Dafny.Helpers.ComprehensionDelegate<{0}>)delegate() {{ ", typeName);
wr.Write("var {0} = new System.Collections.Generic.List<{1}>(); ", collection_name, typeName);
var n = e.BoundVars.Count;
Contract.Assert(e.Bounds.Count == n);
for (int i = 0; i < n; i++) {
var bound = e.Bounds[i];
var bv = e.BoundVars[i];
if (bound is ComprehensionExpr.BoolBoundedPool) {
wr.Write("foreach (var @{0} in Dafny.Helpers.AllBooleans) {{ ", bv.CompileName);
} else if (bound is ComprehensionExpr.CharBoundedPool) {
wr.Write("foreach (var @{0} in Dafny.Helpers.AllChars) {{ ", bv.CompileName);
} else if (bound is ComprehensionExpr.IntBoundedPool) {
var b = (ComprehensionExpr.IntBoundedPool)bound;
if (AsNativeType(bv.Type) != null) {
wr.Write("foreach (var @{0} in @{1}.IntegerRange(", bv.CompileName, bv.Type.AsNewtype.FullCompileName);
} else {
wr.Write("foreach (var @{0} in Dafny.Helpers.IntegerRange(", bv.CompileName);
}
TrExpr(b.LowerBound, wr, inLetExprBody);
wr.Write(", ");
TrExpr(b.UpperBound, wr, inLetExprBody);
wr.Write(")) { ");
} else if (bound is ComprehensionExpr.SetBoundedPool) {
var b = (ComprehensionExpr.SetBoundedPool)bound;
wr.Write("foreach (var @{0} in (", bv.CompileName);
TrExpr(b.Set, wr, inLetExprBody);
wr.Write(").Elements) { ");
} else if (bound is ComprehensionExpr.MapBoundedPool) {
var b = (ComprehensionExpr.MapBoundedPool)bound;
wr.Write("foreach (var @{0} in (", bv.CompileName);
TrExpr(b.Map, wr, inLetExprBody);
wr.Write(").Domain) { ");
} else if (bound is ComprehensionExpr.SeqBoundedPool) {
var b = (ComprehensionExpr.SeqBoundedPool)bound;
wr.Write("foreach (var @{0} in (", bv.CompileName);
TrExpr(b.Seq, wr, inLetExprBody);
wr.Write(").Elements) { ");
} else if (bound is ComprehensionExpr.DatatypeBoundedPool) {
var b = (ComprehensionExpr.DatatypeBoundedPool)bound;
wr.Write("foreach (var @{0} in {1}.AllSingletonConstructors) {{", bv.CompileName, TypeName(bv.Type, wr));
} else {
Contract.Assert(false); throw new cce.UnreachableException(); // unexpected BoundedPool type
}
}
wr.Write("if (");
TrExpr(e.Range, wr, inLetExprBody);
wr.Write(") {");
wr.Write("{0}.Add(", collection_name);
TrExpr(e.Term, wr, inLetExprBody);
wr.Write("); }");
for (int i = 0; i < n; i++) {
wr.Write("}");
}
wr.Write("return Dafny.Set<{0}>.FromCollection({1}); ", typeName, collection_name);
wr.Write("})()");
} else if (expr is MapComprehension) {
var e = (MapComprehension)expr;
// For "map i | R(i) :: Term(i)" where the term has type "V" and i has type "U", emit something like:
// ((MapComprehensionDelegate<U, V>)delegate() {
// var _coll = new List<Pair<U,V>>();
// foreach (L l in sq.Elements) {
// foreach (K k in st.Elements) {
// for (BigInteger j = Lo; j < Hi; j++) {
// for (bool i in Helper.AllBooleans) {
// if (R(i,j,k,l)) {
// _coll.Add(new Pair(i, Term(i));
// }
// }
// }
// }
// }
// return Dafny.Map<U, V>.FromElements(_coll);
// })()
Contract.Assert(e.Bounds != null); // the resolver would have insisted on finding bounds
var domtypeName = TypeName(e.Type.AsMapType.Domain, wr);
var rantypeName = TypeName(e.Type.AsMapType.Range, wr);
var collection_name = idGenerator.FreshId("_coll");
wr.Write("((Dafny.Helpers.MapComprehensionDelegate<{0},{1}>)delegate() {{ ", domtypeName, rantypeName);
wr.Write("var {0} = new System.Collections.Generic.List<Dafny.Pair<{1},{2}>>(); ", collection_name, domtypeName, rantypeName);
var n = e.BoundVars.Count;
Contract.Assert(e.Bounds.Count == n && n == 1);
var bound = e.Bounds[0];
var bv = e.BoundVars[0];
if (bound is ComprehensionExpr.BoolBoundedPool) {
wr.Write("foreach (var @{0} in Dafny.Helpers.AllBooleans) {{ ", bv.CompileName);
} else if (bound is ComprehensionExpr.CharBoundedPool) {
wr.Write("foreach (var @{0} in Dafny.Helpers.AllChars) {{ ", bv.CompileName);
} else if (bound is ComprehensionExpr.IntBoundedPool) {
var b = (ComprehensionExpr.IntBoundedPool)bound;
if (AsNativeType(bv.Type) != null) {
wr.Write("foreach (var @{0} in @{1}.IntegerRange(", bv.CompileName, bv.Type.AsNewtype.FullCompileName);
} else {
wr.Write("foreach (var @{0} in Dafny.Helpers.IntegerRange(", bv.CompileName);
}
TrExpr(b.LowerBound, wr, inLetExprBody);
wr.Write(", ");
TrExpr(b.UpperBound, wr, inLetExprBody);
wr.Write(")) { ");
} else if (bound is ComprehensionExpr.SetBoundedPool) {
var b = (ComprehensionExpr.SetBoundedPool)bound;
wr.Write("foreach (var @{0} in (", bv.CompileName);
TrExpr(b.Set, wr, inLetExprBody);
wr.Write(").Elements) { ");
} else if (bound is ComprehensionExpr.MapBoundedPool) {
var b = (ComprehensionExpr.MapBoundedPool)bound;
wr.Write("foreach (var @{0} in (", bv.CompileName);
TrExpr(b.Map, wr, inLetExprBody);
wr.Write(").Domain) { ");
} else if (bound is ComprehensionExpr.SeqBoundedPool) {
var b = (ComprehensionExpr.SeqBoundedPool)bound;
wr.Write("foreach (var @{0} in (", bv.CompileName);
TrExpr(b.Seq, wr, inLetExprBody);
wr.Write(").Elements) { ");
} else {
// TODO: handle ComprehensionExpr.SubSetBoundedPool
Contract.Assert(false); throw new cce.UnreachableException(); // unexpected BoundedPool type
}
wr.Write("if (");
TrExpr(e.Range, wr, inLetExprBody);
wr.Write(") { ");
wr.Write("{0}.Add(new Dafny.Pair<{1},{2}>(@{3},", collection_name, domtypeName, rantypeName, bv.CompileName);
TrExpr(e.Term, wr, inLetExprBody);
wr.Write(")); }");
wr.Write("}");
wr.Write("return Dafny.Map<{0},{1}>.FromCollection({2}); ", domtypeName, rantypeName, collection_name);
wr.Write("})()");
} else if (expr is LambdaExpr) {
LambdaExpr e = (LambdaExpr)expr;
var fvs = Translator.ComputeFreeVariables(expr);
var sm = new Dictionary<IVariable, Expression>();
var bvars = new List<BoundVar>();
var fexprs = new List<Expression>();
foreach(var fv in fvs) {
fexprs.Add(new IdentifierExpr(fv.Tok, fv.Name) {
Var = fv, // resolved here!
Type = fv.Type
});
var bv = new BoundVar(fv.Tok, fv.Name, fv.Type);
bvars.Add(bv);
sm[fv] = new IdentifierExpr(bv.Tok, bv.Name) {
Var = bv, // resolved here!
Type = bv.Type
};
}
var su = new Translator.Substituter(null, sm, new Dictionary<TypeParameter, Type>(), null);
BetaRedex(bvars, fexprs, expr.Type, wr, inLetExprBody, () => {
wr.Write("(");
wr.Write(Util.Comma(e.BoundVars, bv => "@" + bv.CompileName));
wr.Write(") => ");
TrExpr(su.Substitute(e.Body), wr, inLetExprBody);
});
} else if (expr is StmtExpr) {
var e = (StmtExpr)expr;
TrExpr(e.E, wr, inLetExprBody);
} else if (expr is ITEExpr) {
ITEExpr e = (ITEExpr)expr;
wr.Write("(");
TrExpr(e.Test, wr, inLetExprBody);
wr.Write(") ? (");
TrExpr(e.Thn, wr, inLetExprBody);
wr.Write(") : (");
TrExpr(e.Els, wr, inLetExprBody);
wr.Write(")");
} else if (expr is ConcreteSyntaxExpression) {
var e = (ConcreteSyntaxExpression)expr;
TrExpr(e.ResolvedExpression, wr, inLetExprBody);
} else if (expr is NamedExpr) {
TrExpr(((NamedExpr)expr).Body, wr, inLetExprBody);
} else {
Contract.Assert(false); throw new cce.UnreachableException(); // unexpected expression
}
}
public void AcceptMethodCallsVisitOnVisitorWithThis()
{
var name = new IdentifierExpr(RandomGenerator.String());
var arguments = new VarDefinitionStmt[0];
var body = new NoOpStatement();
var returnType = new IdentifierExpr(RandomGenerator.String());
var target = new FunctionDefinitionExpr(name, arguments, body, returnType);
var visitor = new Mock<IExpressionVisitor<string, int>>();
target.Accept(visitor.Object, 0);
visitor.Verify(x => x.Visit(target, 0), Times.Once);
}
public override Expr VisitIdentifierExpr(IdentifierExpr node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Expr>() != null);
return base.VisitIdentifierExpr((IdentifierExpr)node.Clone());
}
public void ProtectedLambdaExprBody()
{
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 lambda = new LambdaExpr(Token.NoToken, new List<TypeVariable>(), new List<Variable>() { x, y},
null, body, /*immutable=*/true);
lambda.Body = Expr.Lt(xId, yId); // Changing the body of an immutable ExistsExpr should fail
}
private void PredicateBlock(Expr pExpr, Block block, List<Block> newBlocks, ref Block prevBlock) {
var firstBlock = block;
var oldCmdSeq = block.Cmds;
block.Cmds = new List<Cmd>();
newBlocks.Add(block);
if (prevBlock != null && !((prevBlock.TransferCmd is ReturnCmd) && uni != null && uni.IsUniform(impl.Name, block))) {
prevBlock.TransferCmd = new GotoCmd(Token.NoToken, new List<Block> { block });
}
Block currentBlock = block;
Expr pCurrentExpr = pExpr;
while (parentMap.ContainsKey(currentBlock)) {
Block parent = parentMap[currentBlock];
Expr pParentExpr = null;
if (predMap.ContainsKey(parent)) {
var parentPred = predMap[parent];
if (parentPred != null) {
pParentExpr = Expr.Ident(parentPred);
block.Cmds.Add(new AssertCmd(Token.NoToken,
pCurrentExpr != null ? (Expr)Expr.Imp(pCurrentExpr, pParentExpr)
: pParentExpr));
}
}
currentBlock = parent;
pCurrentExpr = pParentExpr;
}
Block dominator = FindImmediateDominator(block);
Expr pDomExpr = Expr.True;
if (dominator != null && predMap.ContainsKey(dominator))
pDomExpr = new IdentifierExpr(Token.NoToken, predMap[dominator]);
var transferCmd = block.TransferCmd;
foreach (Cmd cmd in oldCmdSeq)
PredicateCmd(pExpr, pDomExpr, newBlocks, block, cmd, out block);
if (ownedMap.ContainsKey(firstBlock)) {
var owned = ownedMap[firstBlock];
foreach (var v in owned)
block.Cmds.Add(Cmd.SimpleAssign(Token.NoToken, Expr.Ident(v), Expr.False));
}
bool hasPredicatedRegion;
PredicateTransferCmd(pExpr, block, block.Cmds, transferCmd, out hasPredicatedRegion);
if (hasPredicatedRegion)
prevBlock = block;
else
prevBlock = null;
doneBlocks.Add(block);
}
void PredicateImplementation() {
blockGraph = prog.ProcessLoops(impl);
sortedBlocks = blockGraph.LoopyTopSort();
AssignPredicates();
partInfo = BuildPartitionInfo();
if (myUseProcedurePredicates)
fp = Expr.Ident(impl.InParams[0]);
var newBlocks = new List<Block>();
Block prevBlock = null;
foreach (var n in sortedBlocks) {
if (predMap.ContainsKey(n.Item1)) {
var p = predMap[n.Item1];
var pExpr = Expr.Ident(p);
if (n.Item2) {
var dominator = FindImmediateDominator(n.Item1);
if (dominator != null && predMap.ContainsKey(dominator)) {
AssumeCmd aCmd = new AssumeCmd(Token.NoToken, Expr.True);
aCmd.Attributes = new QKeyValue(Token.NoToken, "dominator_predicate", new List<object>() { predMap[dominator].ToString() }, aCmd.Attributes);
aCmd.Attributes = new QKeyValue(Token.NoToken, "predicate", new List<object>() { predMap[n.Item1].ToString() }, aCmd.Attributes);
n.Item1.Cmds.Insert(0, aCmd);
}
var backedgeBlock = new Block();
newBlocks.Add(backedgeBlock);
backedgeBlock.Label = n.Item1.Label + ".backedge";
backedgeBlock.Cmds = new List<Cmd> { new AssumeCmd(Token.NoToken, pExpr,
new QKeyValue(Token.NoToken, "backedge", new List<object>(), null)) };
backedgeBlock.TransferCmd = new GotoCmd(Token.NoToken,
new List<Block> { n.Item1 });
var tailBlock = new Block();
newBlocks.Add(tailBlock);
tailBlock.Label = n.Item1.Label + ".tail";
tailBlock.Cmds = new List<Cmd> { new AssumeCmd(Token.NoToken,
Expr.Not(pExpr)) };
if (uni != null && !uni.IsUniform(impl.Name, n.Item1)) {
uni.AddNonUniform(impl.Name, backedgeBlock);
uni.AddNonUniform(impl.Name, tailBlock);
}
if (prevBlock != null)
prevBlock.TransferCmd = new GotoCmd(Token.NoToken,
new List<Block> { backedgeBlock, tailBlock });
prevBlock = tailBlock;
} else {
PredicateBlock(pExpr, n.Item1, newBlocks, ref prevBlock);
}
} else {
if (!n.Item2) {
PredicateBlock(null, n.Item1, newBlocks, ref prevBlock);
}
}
}
if (prevBlock != null)
prevBlock.TransferCmd = new ReturnCmd(Token.NoToken);
impl.Blocks = newBlocks;
}
void PredicateImplementation()
{
blockGraph = prog.ProcessLoops(impl);
var sortedBlocks = blockGraph.LoopyTopSort();
int blockId = 0;
foreach (var block in impl.Blocks)
blockIds[block] = Expr.Literal(blockId++);
returnBlockId = Expr.Literal(blockId++);
curVar = new LocalVariable(Token.NoToken,
new TypedIdent(Token.NoToken, "cur",
Microsoft.Boogie.Type.Int));
impl.LocVars.Add(curVar);
cur = Expr.Ident(curVar);
pVar = new LocalVariable(Token.NoToken,
new TypedIdent(Token.NoToken, "p",
Microsoft.Boogie.Type.Bool));
impl.LocVars.Add(pVar);
p = Expr.Ident(pVar);
if (useProcedurePredicates)
fp = Expr.Ident(impl.InParams[0]);
var newBlocks = new List<Block>();
Block entryBlock = new Block();
entryBlock.Label = "entry";
entryBlock.Cmds = new List<Cmd> { Cmd.SimpleAssign(Token.NoToken, cur,
CreateIfFPThenElse(blockIds[sortedBlocks[0].Item1],
returnBlockId)) };
newBlocks.Add(entryBlock);
var prevBlock = entryBlock;
foreach (var n in sortedBlocks) {
if (n.Item2) {
var backedgeBlock = new Block();
newBlocks.Add(backedgeBlock);
backedgeBlock.Label = n.Item1.Label + ".backedge";
backedgeBlock.Cmds = new List<Cmd> { new AssumeCmd(Token.NoToken,
Expr.Eq(cur, blockIds[n.Item1]),
new QKeyValue(Token.NoToken, "backedge", new List<object>(), null)) };
backedgeBlock.TransferCmd = new GotoCmd(Token.NoToken,
new List<Block> { n.Item1 });
var tailBlock = new Block();
newBlocks.Add(tailBlock);
tailBlock.Label = n.Item1.Label + ".tail";
tailBlock.Cmds = new List<Cmd> { new AssumeCmd(Token.NoToken,
Expr.Neq(cur, blockIds[n.Item1])) };
prevBlock.TransferCmd = new GotoCmd(Token.NoToken,
new List<Block> { backedgeBlock, tailBlock });
prevBlock = tailBlock;
} else {
var runBlock = n.Item1;
var oldCmdSeq = runBlock.Cmds;
runBlock.Cmds = new List<Cmd>();
newBlocks.Add(runBlock);
prevBlock.TransferCmd = new GotoCmd(Token.NoToken,
new List<Block> { runBlock });
pExpr = Expr.Eq(cur, blockIds[runBlock]);
if (createCandidateInvariants && blockGraph.Headers.Contains(runBlock)) {
AddUniformCandidateInvariant(runBlock.Cmds, runBlock);
AddNonUniformCandidateInvariant(runBlock.Cmds, runBlock);
}
runBlock.Cmds.Add(Cmd.SimpleAssign(Token.NoToken, p, pExpr));
var transferCmd = runBlock.TransferCmd;
foreach (Cmd cmd in oldCmdSeq)
PredicateCmd(newBlocks, runBlock, cmd, out runBlock);
PredicateTransferCmd(runBlock.Cmds, transferCmd);
prevBlock = runBlock;
doneBlocks.Add(runBlock);
}
}
prevBlock.TransferCmd = new ReturnCmd(Token.NoToken);
impl.Blocks = newBlocks;
}
public override Cmd VisitCallCmd(CallCmd node)
{
var result = base.VisitCallCmd(node);
var oldProc = programInCachedSnapshot.FindProcedure(node.Proc.Name);
if (oldProc != null
&& oldProc.DependencyChecksum != node.Proc.DependencyChecksum
&& node.AssignedAssumptionVariable == null)
{
var before = new List<Cmd>();
var beforePrecondtionCheck = new List<Cmd>();
var after = new List<Cmd>();
var axioms = new List<Axiom>();
Expr assumedExpr = new LiteralExpr(Token.NoToken, false);
// TODO(wuestholz): Try out two alternatives: only do this for low priority implementations or not at all.
var canUseSpecs = DependencyCollector.CanExpressOldSpecs(oldProc, Program);
if (canUseSpecs && oldProc.SignatureEquals(node.Proc))
{
var desugaring = node.Desugaring;
Contract.Assert(desugaring != null);
var precond = node.CheckedPrecondition(oldProc, Program, e => FunctionExtractor.Extract(e, Program, axioms));
if (precond != null)
{
var assume = new AssumeCmd(node.tok, precond, new QKeyValue(Token.NoToken, "precondition_previous_snapshot", new List<object>(), null));
assume.IrrelevantForChecksumComputation = true;
beforePrecondtionCheck.Add(assume);
}
var unmods = node.UnmodifiedBefore(oldProc);
var eqs = new List<Expr>();
foreach (var unmod in unmods)
{
var oldUnmod = new LocalVariable(Token.NoToken,
new TypedIdent(Token.NoToken, string.Format("{0}##old##{1}", unmod.Name, FreshTemporaryVariableName), unmod.Type));
var lhs = new SimpleAssignLhs(Token.NoToken, new IdentifierExpr(Token.NoToken, oldUnmod));
var rhs = new IdentifierExpr(Token.NoToken, unmod.Decl);
var cmd = new AssignCmd(Token.NoToken, new List<AssignLhs> { lhs }, new List<Expr> { rhs });
cmd.IrrelevantForChecksumComputation = true;
before.Add(cmd);
var eq = LiteralExpr.Eq(new IdentifierExpr(Token.NoToken, oldUnmod), new IdentifierExpr(Token.NoToken, unmod.Decl));
eq.Type = Type.Bool;
eq.TypeParameters = SimpleTypeParamInstantiation.EMPTY;
eqs.Add(eq);
}
var mods = node.ModifiedBefore(oldProc);
var oldSubst = new Dictionary<Variable, Expr>();
foreach (var mod in mods)
{
var oldMod = new LocalVariable(Token.NoToken,
new TypedIdent(Token.NoToken, string.Format("{0}##old##{1}", mod.Name, FreshTemporaryVariableName), mod.Type));
oldSubst[mod.Decl] = new IdentifierExpr(Token.NoToken, oldMod);
var lhs = new SimpleAssignLhs(Token.NoToken, new IdentifierExpr(Token.NoToken, oldMod));
var rhs = new IdentifierExpr(Token.NoToken, mod.Decl);
var cmd = new AssignCmd(Token.NoToken, new List<AssignLhs> { lhs }, new List<Expr> { rhs });
cmd.IrrelevantForChecksumComputation = true;
before.Add(cmd);
}
assumedExpr = node.Postcondition(oldProc, eqs, oldSubst, Program, e => FunctionExtractor.Extract(e, Program, axioms));
if (assumedExpr == null)
{
assumedExpr = new LiteralExpr(Token.NoToken, true);
}
}
if (assumedExpr != null)
{
var lv = new LocalVariable(Token.NoToken,
new TypedIdent(Token.NoToken, string.Format("a##cached##{0}", FreshAssumptionVariableName), Type.Bool),
new QKeyValue(Token.NoToken, "assumption", new List<object>(), null));
node.AssignedAssumptionVariable = lv;
currentImplementation.InjectAssumptionVariable(lv, !canUseSpecs);
var lhs = new SimpleAssignLhs(Token.NoToken, new IdentifierExpr(Token.NoToken, lv));
var rhs = LiteralExpr.And(new IdentifierExpr(Token.NoToken, lv), assumedExpr);
var assumed = new AssignCmd(node.tok, new List<AssignLhs> { lhs }, new List<Expr> { rhs });
assumed.IrrelevantForChecksumComputation = true;
after.Add(assumed);
}
node.ExtendDesugaring(before, beforePrecondtionCheck, after);
if (CommandLineOptions.Clo.TraceCachingForTesting || CommandLineOptions.Clo.TraceCachingForBenchmarking)
{
using (var tokTxtWr = new TokenTextWriter("<console>", Console.Out, false, false))
{
var loc = node.tok != null && node.tok != Token.NoToken ? string.Format("{0}({1},{2})", node.tok.filename, node.tok.line, node.tok.col) : "<unknown location>";
Console.Out.WriteLine("Processing call to procedure {0} in implementation {1} (at {2}):", node.Proc.Name, currentImplementation.Name, loc);
foreach (var a in axioms)
{
Console.Out.Write(" >>> added axiom: ");
a.Expr.Emit(tokTxtWr);
Console.Out.WriteLine();
}
foreach (var b in before)
{
Console.Out.Write(" >>> added before: ");
b.Emit(tokTxtWr, 0);
}
foreach (var b in beforePrecondtionCheck)
{
Console.Out.Write(" >>> added before precondition check: ");
b.Emit(tokTxtWr, 0);
}
foreach (var a in after)
{
Console.Out.Write(" >>> added after: ");
a.Emit(tokTxtWr, 0);
}
}
}
}
return result;
}
public void AcceptMethodCallsOnlyVisitOnVisitorWithThisAndNoOtherVisitMethods()
{
var name = new IdentifierExpr(RandomGenerator.String());
var arguments = new VarDefinitionStmt[0];
var body = new NoOpStatement();
var returnType = new IdentifierExpr(RandomGenerator.String());
var target = new FunctionDefinitionExpr(name, arguments, body, returnType);
// throw exception is any other methods called other than the PlusExpr overload.
var visitor = new Mock<IExpressionVisitor<string, int>>(MockBehavior.Strict);
visitor.Setup(x => x.Visit(target, 1234)).Returns("");
target.Accept(visitor.Object, 1234);
}
private NAryExpr GetUnTypedImmutableNAry()
{
var id = new IdentifierExpr(Token.NoToken, "foo", BasicType.Bool, /*immutable=*/true);
Assert.IsTrue(id.Immutable);
Assert.IsTrue(id.Type.IsBool);
var e = new NAryExpr(Token.NoToken, new BinaryOperator(Token.NoToken, BinaryOperator.Opcode.And), new List<Expr>() {
id,
id
}, /*immutable=*/true);
Assert.IsNull(e.Type);
Assert.IsTrue(e.Immutable);
return e;
}
public void ProtectedForAllExprBody()
{
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 forAll = new ForallExpr(Token.NoToken, new List<Variable> () { x, y }, body, /*immutable=*/true);
forAll.Body = Expr.Lt(xId, yId); // Changing the body of an immutable ForAllExpr should fail
}
void PredicateCmd(Expr p, Expr pDom, List<Cmd> cmdSeq, Cmd cmd) {
if (cmd is CallCmd) {
var cCmd = (CallCmd)cmd;
Debug.Assert(useProcedurePredicates(cCmd.Proc));
cCmd.Ins.Insert(0, p != null ? p : Expr.True);
cmdSeq.Add(cCmd);
} else if (p == null) {
new EnabledReplacementVisitor(Expr.True, pDom).Visit(cmd);
cmdSeq.Add(cmd);
} else if (cmd is AssignCmd) {
var aCmd = (AssignCmd)cmd;
cmdSeq.Add(new AssignCmd(Token.NoToken, aCmd.Lhss,
new List<Expr>(aCmd.Lhss.Zip(aCmd.Rhss, (lhs, rhs) =>
new NAryExpr(Token.NoToken,
new IfThenElse(Token.NoToken),
new List<Expr> { p, rhs, lhs.AsExpr })))));
} else if (cmd is AssertCmd) {
var aCmd = (AssertCmd)cmd;
Expr newExpr = new EnabledReplacementVisitor(p, pDom).VisitExpr(aCmd.Expr);
aCmd.Expr = QKeyValue.FindBoolAttribute(aCmd.Attributes, "do_not_predicate") ? newExpr : Expr.Imp(p, newExpr);
cmdSeq.Add(aCmd);
} else if (cmd is AssumeCmd) {
var aCmd = (AssumeCmd)cmd;
Expr newExpr = new EnabledReplacementVisitor(p, pDom).VisitExpr(aCmd.Expr);
aCmd.Expr = QKeyValue.FindBoolAttribute(aCmd.Attributes, "do_not_predicate") ? newExpr : Expr.Imp(p, newExpr);
cmdSeq.Add(aCmd);
} else if (cmd is HavocCmd) {
var hCmd = (HavocCmd)cmd;
foreach (IdentifierExpr v in hCmd.Vars) {
Microsoft.Boogie.Type type = v.Decl.TypedIdent.Type;
Contract.Assert(type != null);
IdentifierExpr havocTempExpr;
if (havocVars.ContainsKey(type)) {
havocTempExpr = havocVars[type];
} else {
var havocVar = new LocalVariable(Token.NoToken,
new TypedIdent(Token.NoToken,
"_HAVOC_" + type.ToString(), type));
impl.LocVars.Add(havocVar);
havocVars[type] = havocTempExpr =
new IdentifierExpr(Token.NoToken, havocVar);
}
cmdSeq.Add(new HavocCmd(Token.NoToken,
new List<IdentifierExpr> { havocTempExpr }));
cmdSeq.Add(Cmd.SimpleAssign(Token.NoToken, v,
new NAryExpr(Token.NoToken,
new IfThenElse(Token.NoToken),
new List<Expr> { p, havocTempExpr, v })));
}
} else if (cmd is CommentCmd) {
// skip
} else if (cmd is StateCmd) {
var sCmd = (StateCmd)cmd;
var newCmdSeq = new List<Cmd>();
foreach (Cmd c in sCmd.Cmds)
PredicateCmd(p, pDom, newCmdSeq, c);
sCmd.Cmds = newCmdSeq;
cmdSeq.Add(sCmd);
} else {
Console.WriteLine("Unsupported cmd: " + cmd.GetType().ToString());
}
}
void PredicateCmd(List<Cmd> cmdSeq, Cmd cmd)
{
if (cmd is AssignCmd) {
var aCmd = (AssignCmd)cmd;
cmdSeq.Add(new AssignCmd(Token.NoToken, aCmd.Lhss,
new List<Expr>(aCmd.Lhss.Zip(aCmd.Rhss, (lhs, rhs) =>
new NAryExpr(Token.NoToken,
new IfThenElse(Token.NoToken),
new List<Expr> { p, rhs, lhs.AsExpr })))));
} else if (cmd is AssertCmd) {
var aCmd = (AssertCmd)cmd;
if (cmdSeq.Last() is AssignCmd &&
cmdSeq.Cast<Cmd>().SkipEnd(1).All(c => c is AssertCmd)) {
// This may be a loop invariant. Make sure it continues to appear as
// the first statement in the block.
var assign = cmdSeq.Last();
cmdSeq.RemoveAt(cmdSeq.Count-1);
Expr newExpr = new EnabledReplacementVisitor(pExpr).VisitExpr(aCmd.Expr);
aCmd.Expr = QKeyValue.FindBoolAttribute(aCmd.Attributes, "do_not_predicate") ? newExpr : Expr.Imp(pExpr, newExpr);
cmdSeq.Add(aCmd);
// cmdSeq.Add(new AssertCmd(aCmd.tok, Expr.Imp(pExpr, aCmd.Expr)));
cmdSeq.Add(assign);
} else {
aCmd.Expr = Expr.Imp(p, aCmd.Expr);
cmdSeq.Add(aCmd);
// cmdSeq.Add(new AssertCmd(aCmd.tok, Expr.Imp(p, aCmd.Expr)));
}
} else if (cmd is AssumeCmd) {
var aCmd = (AssumeCmd)cmd;
cmdSeq.Add(new AssumeCmd(Token.NoToken, Expr.Imp(p, aCmd.Expr)));
} else if (cmd is HavocCmd) {
var hCmd = (HavocCmd)cmd;
foreach (IdentifierExpr v in hCmd.Vars) {
Microsoft.Boogie.Type type = v.Decl.TypedIdent.Type;
Contract.Assert(type != null);
IdentifierExpr havocTempExpr;
if (havocVars.ContainsKey(type)) {
havocTempExpr = havocVars[type];
} else {
var havocVar = new LocalVariable(Token.NoToken,
new TypedIdent(Token.NoToken,
"_HAVOC_" + type.ToString(), type));
impl.LocVars.Add(havocVar);
havocVars[type] = havocTempExpr =
new IdentifierExpr(Token.NoToken, havocVar);
}
cmdSeq.Add(new HavocCmd(Token.NoToken,
new List<IdentifierExpr> { havocTempExpr }));
cmdSeq.Add(Cmd.SimpleAssign(Token.NoToken, v,
new NAryExpr(Token.NoToken,
new IfThenElse(Token.NoToken),
new List<Expr> { p, havocTempExpr, v })));
}
} else if (cmd is CallCmd) {
Debug.Assert(useProcedurePredicates);
var cCmd = (CallCmd)cmd;
cCmd.Ins.Insert(0, p);
cmdSeq.Add(cCmd);
}
else if (cmd is CommentCmd) {
// skip
}
else if (cmd is StateCmd) {
var sCmd = (StateCmd)cmd;
var newCmdSeq = new List<Cmd>();
foreach (Cmd c in sCmd.Cmds)
PredicateCmd(newCmdSeq, c);
sCmd.Cmds = newCmdSeq;
cmdSeq.Add(sCmd);
}
else {
Console.WriteLine("Unsupported cmd: " + cmd.GetType().ToString());
}
}
public static IdentifierExpr MakeIdentifierExpr(string name, Type type, bool isGhost)
{
Util.Assert(type != null);
IdentifierExpr id = new IdentifierExpr(Bpl.Token.NoToken, name);
id.Type = type;
id.Var = new LocalVariable(Bpl.Token.NoToken, Bpl.Token.NoToken, name, type, isGhost);
return id;
}
public override Expr VisitIdentifierExpr(IdentifierExpr node) {
//Contract.Requires(node != null);
Contract.Ensures(Contract.Result<Expr>() != null);
Expr/*?*/ e = null;
if (insideOldExpr) {
e = forold(cce.NonNull(node.Decl));
}
if (e == null) {
e = always(cce.NonNull(node.Decl));
}
return e == null ? base.VisitIdentifierExpr(node) : e;
}
public override void Visit(IdentifierExpr identifierNode)
{
identifierNode.ExprValue = SymbolTable.GetSymbolValue(identifierNode.IdentifierName);
}
public Tuple<Method,TypeApply> GetSeqBuildMethod(Type t, SeqTree tree, List<bool> elemDimensions)
{
if (elemDimensions.Count == 0)
{
return GetSeqMethod(t, "seq_Empty");
}
if (elemDimensions.Count == 2 && elemDimensions[0] && elemDimensions[1])
{
return GetSeqMethod(t, "seq_Append");
}
string op = "seq_" + SeqTree.TreeName(tree);
DatatypeDecl seqDecl = FindDatatype("Seq");
var tok = new Bpl.Token(0, 0);
tok.filename = @"!\Seq.dfy";
TypeApply tApp = Compile_SeqType((SeqType)t);
Type dataType = new UserDefinedType(tok, "Seq", seqDecl, new List<Type> { ((SeqType)t).Arg });
Type elemType = ((SeqType)t).Arg;
Func<string,Type,Expression> idExpr = (x, typ) => {
var e = new IdentifierExpr(tok, x);
e.Type = typ;
e.Var = new LocalVariable(tok, tok, x, typ, false);
return e;
};
Func<string,List<Expression>,FunctionCallExpr> seqCall = (x, args) => {
var seqOp = GetSeqOperation(t, x);
FunctionCallExpr callExpr = new FunctionCallExpr(
tok, "Seq_Empty", new ThisExpr(tok), tok, args);
callExpr.Function = seqOp.Item1;
callExpr.TypeArgumentSubstitutions = seqOp.Item2.typeArgs;
return callExpr;
};
Expression empty = seqCall("Seq_Empty", new List<Expression> {});
int varCount = 0;
Func<SeqTree,Expression> resultRec = null;
resultRec = (subtree) =>
{
if (subtree == null)
{
return idExpr("s" + (varCount++), dataType);
}
if (subtree.buildCount >= 0)
{
Expression build = empty;
for (int i = 0; i < subtree.buildCount; i++)
{
build = seqCall("Seq_Build", new List<Expression>
{ build, idExpr("a" + (varCount++), elemType) });
}
return build;
}
else
{
return seqCall("Seq_Append", new List<Expression>
{ resultRec(subtree.left), resultRec(subtree.right) });
}
};
Expression result = resultRec(tree);
Expression post = seqCall("Seq_Equal", new List<Expression> { idExpr("s", dataType), result });
List<Statement> stmts = new List<Statement>();
for (int i = elemDimensions.Count; i > 0;)
{
bool isFirst = (i == elemDimensions.Count);
i--;
if (elemDimensions[i])
{
if (isFirst)
{
stmts.Add(new AssignStmt(tok, tok, idExpr("s", dataType),
new ExprRhs(idExpr("s" + i, dataType))));
}
else
{
// s := seq_Append(s9, s);
var selectExpr = new MemberSelectExpr(tok, new ThisExpr(tok), "seq_Append");
selectExpr.Member = FindMethod(selectExpr.MemberName); // Manually resolve here
selectExpr.TypeApplication = new List<Type>() { elemType }; // Manually resolve here
selectExpr.Type = new InferredTypeProxy(); // Manually resolve here
CallStmt callStmt = new CallStmt(tok, tok,
new List<Expression> {idExpr("s", dataType)},
selectExpr, new List<Expression>
{ idExpr("s" + i, dataType), idExpr("s", dataType) });
stmts.Add(callStmt);
}
}
else
{
if (isFirst)
{
DatatypeValue nil = new DatatypeValue(tok, "Seq", "Nil", new List<Expression>() {});
nil.Type = dataType;
nil.InferredTypeArgs = new List<Type> { elemType };
nil.Ctor = seqDecl.Ctors[0];
Util.Assert(nil.Ctor.Name == "Seq_Nil");
stmts.Add(new AssignStmt(tok, tok, idExpr("s", dataType), new ExprRhs(nil)));
}
// lemma_Seq_Cons(ai, s);
var selectExpr = new MemberSelectExpr(tok, new ThisExpr(tok), "lemma_Seq_Cons");
selectExpr.Member = FindMethod(selectExpr.MemberName); // Manually resolve here
selectExpr.TypeApplication = new List<Type>() { elemType }; // Manually resolve here
selectExpr.Type = new InferredTypeProxy(); // Manually resolve here
CallStmt callStmt = new CallStmt(tok, tok,
new List<Expression> {},
selectExpr, new List<Expression>
{ idExpr("a" + i, elemType), idExpr("s", dataType) });
callStmt.IsGhost = true;
stmts.Add(callStmt);
DatatypeValue cons = new DatatypeValue(tok, "Seq", "Cons", new List<Expression>()
{ idExpr("a" + i, elemType), idExpr("s", dataType) });
cons.Type = dataType;
cons.InferredTypeArgs = new List<Type> { elemType };
cons.Ctor = seqDecl.Ctors[1];
Util.Assert(cons.Ctor.Name == "Seq_Cons");
stmts.Add(new AssignStmt(tok, tok, idExpr("s", dataType), new ExprRhs(cons)));
}
}
BlockStmt body = new BlockStmt(tok, tok, stmts);
List<Formal> ins = new List<Formal>();
for (int i = 0; i < elemDimensions.Count; i++)
{
bool isSeq = elemDimensions[i];
ins.Add(new Formal(tok, (isSeq ? "s" : "a") + i, isSeq ? dataType : elemType, true, false));
}
List<Formal> outs = new List<Formal> { new Formal(tok, "s", dataType, false, false) };
List<MaybeFreeExpression> reqs = new List<MaybeFreeExpression>();
List<MaybeFreeExpression> enss = new List<MaybeFreeExpression> { new MaybeFreeExpression(post) };
Specification<FrameExpression> mods = new Specification<FrameExpression>(new List<FrameExpression>(), null);
Specification<Expression> decs = new Specification<Expression>(new List<Expression>(), null);
Attributes attrs = new Attributes("dafnycc_conservative_seq_triggers", new List<Expression>(), null);
Method m = new Method(tok, op, true, false, tApp.typeParams, ins, outs, reqs, mods, enss, decs, body, attrs, tok);
m.EnclosingClass = GetSeqMethod(t, "seq_Append").Item1.EnclosingClass;
return Tuple.Create(m, Compile_Method(m, tApp.typeArgs));
}
public override Expr VisitIdentifierExpr(IdentifierExpr node)
{
if (node.Decl == null || !(node.Decl is LocalVariable || node.Decl is Formal || node.Decl is GlobalVariable))
{
return node;
}
else
{
BoundVariable boundVar;
if (!Substitutions.TryGetValue(node.Decl, out boundVar))
{
boundVar = new BoundVariable(Token.NoToken, new TypedIdent(Token.NoToken, node.Name, node.Type));
Substitutions[node.Decl] = boundVar;
}
return new IdentifierExpr(node.tok, boundVar);
}
}