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 VisitExistsExpr(ExistsExpr node)
{
BoundVariables.UnionWith(node.Dummies);
var toReturn = base.VisitExistsExpr(node);
BoundVariables.RemoveWhere(e => node.Dummies.Contains(e));
return(toReturn);
}
public override Expr VisitExistsExpr(ExistsExpr node)
{
if (GetReplacementVariable(node, out var variable))
{
return(new IdentifierExpr(variable.tok, variable));
}
return(base.VisitExistsExpr(node));
}
public QuantifierExpr RewriteMatchingLoops(QuantifierWithTriggers q)
{
// rewrite quantifier to avoid matching 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[j];
substMap = new List <Tuple <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)))
{
var entry = substMap.Find(x => ExprExtensions.ExpressionEq(sub, x.Item1));
if (entry == null)
{
var newBv = new BoundVar(sub.tok, "_t#" + substMap.Count, sub.Type);
var ie = new IdentifierExpr(sub.tok, newBv.Name);
ie.Var = newBv;
ie.Type = newBv.Type;
substMap.Add(new Tuple <Expression, IdentifierExpr>(sub, ie));
}
}
}
}
}
var expr = (QuantifierExpr)q.quantifier;
if (substMap.Count > 0)
{
var s = new 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, Bounds = expr.Bounds
};
}
else
{
expr = new ExistsExpr(expr.tok, expr.TypeArgs, expr.BoundVars, expr.Range, expr.Term, TriggerUtils.CopyAttributes(expr.Attributes))
{
Type = expr.Type, Bounds = expr.Bounds
};
}
}
return(expr);
}
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 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);
// Changing the body of an immutable ExistsExpr should fail
Assert.Throws(typeof(InvalidOperationException), () => exists.Body = Expr.Lt(xId, yId));
}
public static Expr GetChild(this ExistsExpr e, int number)
{
switch (number)
{
case 0:
return(e.Body);
default:
throw new InvalidOperationException("ExistsExpr only has one child");
}
}
public static void SetChild(this ExistsExpr e, int number, Expr NewChild)
{
switch (number)
{
case 0:
e.Body = NewChild;
return;
default:
throw new InvalidOperationException("ExistsExpr only has one child");
}
}
public override Expr VisitExistsExpr(ExistsExpr node)
{
var bodyCopy = this.Visit(node.Body) as Expr;
Debug.Assert(bodyCopy != null);
var freeVars = new List <Variable>(node.Dummies);
var newTriggers = this.VisitTrigger(node.Triggers);
var newNode = Builder.Exists(freeVars, bodyCopy, newTriggers);
Debug.Assert(newNode != null);
return(newNode);
}
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 Expr Exists(IList <Variable> freeVars, Expr body, Trigger triggers = null)
{
if (!body.Type.IsBool)
{
throw new ExprTypeCheckException("body must be of type bool");
}
if (freeVars.Count < 1)
{
throw new ArgumentException("ExistsExpr must have at least one free variable");
}
TypeCheckTriggers(freeVars, body, triggers);
// Should we check the free variables are actually used? This could be quite expensive to do!
var result = new ExistsExpr(Token.NoToken, new List <Variable>(freeVars), triggers, body, Immutable);
result.Type = BasicType.Bool;
return(result);
}
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
}
private static bool ShallowEq(ExistsExpr expr1, ExistsExpr expr2)
{
return(true);
}
public override Expr VisitExistsExpr(ExistsExpr node)
{
return(node);
}
public Expression GetNode(ExpressionParser parser)
{
Lexem lex = parser.Collection.CurrentLexem();
Expression res = null;
if (lex.LexemType == LexType.Command)
{
string lowerLexem = lex.LexemText.ToLower();
if (ParserUtils.ParseCommandPhrase(parser.Collection, "create view", false, false))
{
res = new CreateView();
}
if (ParserUtils.ParseCommandPhrase(parser.Collection, "create table", false, false))
{
res = new CreateTable();
}
if (res == null && ParserUtils.ParseCommandPhrase(parser.Collection, "alter table", false, false))
{
res = new AlterTable();
}
if (res == null && ParserUtils.ParseCommandPhrase(parser.Collection, "drop table", false, false))
{
res = new DropTable();
}
if (res == null && ParserUtils.ParseCommandPhrase(parser.Collection, "drop index", false, false))
{
res = new DropIndex();
}
if (res == null && (ParserUtils.ParseCommandPhrase(parser.Collection, "create unique index", false, false) ||
ParserUtils.ParseCommandPhrase(parser.Collection, "create index", false, false)))
{
res = new CreateIndex();
}
if (res == null)
{
if (parser.Collection.GetNext() != null && parser.Collection.GetNext().IsSkobraOpen())
{
switch (lowerLexem)
{
case "count":
res = new CountExpr();
break;
case "sum":
res = new SumExpr();
break;
case "min":
res = new MinExpr();
break;
case "max":
res = new MaxExpr();
break;
case "avg":
res = new AvgExpr();
break;
case "lastinsertrowid":
res = new LastInsertRowidExpr();
break;
case "exists":
res = new ExistsExpr();
break;
case "any":
res = new AnyExpr();
break;
}
}
switch (lowerLexem)
{
case "between": //не функция
res = new Between();
break;
case "select":
res = new SelectExpresion();
break;
case "update":
res = new UpdateStatement();
break;
case "insert":
res = new InsertStatement();
break;
case "delete":
res = new DeleteStatement();
break;
}
}
}
if (res != null)
{
return(res);
}
return(res);
}
// group split quantifier by what triggers they got, and merged them back into one quantifier.
private void CombineSplitQuantifier()
{
if (quantifiers.Count > 1)
{
List <QuantifierGroup> groups = new List <QuantifierGroup>();
groups.Add(new QuantifierGroup(quantifiers[0], new List <ComprehensionExpr> {
quantifiers[0].quantifier
}));
for (int i = 1; i < quantifiers.Count; i++)
{
bool found = false;
for (int j = 0; j < groups.Count; j++)
{
if (HasSameTriggers(quantifiers[i], groups[j].quantifier))
{
// belong to the same group
groups[j].expressions.Add(quantifiers[i].quantifier);
found = true;
break;
}
}
if (!found)
{
// start a new group
groups.Add(new QuantifierGroup(quantifiers[i], new List <ComprehensionExpr> {
quantifiers[i].quantifier
}));
}
}
if (groups.Count == quantifiers.Count)
{
// have the same number of splits, so no splits are combined.
return;
}
// merge expressions in each group back to one quantifier.
List <QuantifierWithTriggers> list = new List <QuantifierWithTriggers>();
List <Expression> splits = new List <Expression>();
foreach (var group in groups)
{
QuantifierWithTriggers q = group.quantifier;
if (q.quantifier is ForallExpr)
{
ForallExpr quantifier = (ForallExpr)q.quantifier;
Expression expr = QuantifiersToExpression(quantifier.tok, BinaryExpr.ResolvedOpcode.And, group.expressions);
q.quantifier = new ForallExpr(quantifier.tok, quantifier.TypeArgs, quantifier.BoundVars, quantifier.Range, expr, TriggerUtils.CopyAttributes(quantifier.Attributes))
{
Type = quantifier.Type, Bounds = quantifier.Bounds
};
}
else if (q.quantifier is ExistsExpr)
{
ExistsExpr quantifier = (ExistsExpr)q.quantifier;
Expression expr = QuantifiersToExpression(quantifier.tok, BinaryExpr.ResolvedOpcode.Or, group.expressions);
q.quantifier = new ExistsExpr(quantifier.tok, quantifier.TypeArgs, quantifier.BoundVars, quantifier.Range, expr, TriggerUtils.CopyAttributes(quantifier.Attributes))
{
Type = quantifier.Type, Bounds = quantifier.Bounds
};
}
list.Add(q);
splits.Add(q.quantifier);
}
this.quantifiers = list;
Contract.Assert(this.expr is QuantifierExpr); // only QuantifierExpr has SplitQuantifier
((QuantifierExpr)this.expr).SplitQuantifier = splits;
}
}
public override Expr VisitExistsExpr(ExistsExpr node)
{
add(node);
return(base.VisitExistsExpr(node));
}
public Expr VisitExistExpr(ExistsExpr e)
{
return(PrintQuantifierExpr(e));
}
public override Expr VisitExistsExpr(ExistsExpr node)
{
return(base.VisitExistsExpr((ExistsExpr)node.Clone()));
}
public override Expression Substitute(Expression expr)
{
if (TryGetExprSubst(expr, out var ie))
{
Contract.Assert(ie != null);
return(ie);
}
if (expr is QuantifierExpr e)
{
var newAttrs = SubstAttributes(e.Attributes);
var newRange = e.Range == null ? null : Substitute(e.Range);
var newTerm = Substitute(e.Term);
var newBounds = SubstituteBoundedPoolList(e.Bounds);
if (newAttrs == e.Attributes && newRange == e.Range && newTerm == e.Term && newBounds == e.Bounds)
{
return(e);
}
var newBoundVars = new List <BoundVar>(e.BoundVars);
if (newBounds == null)
{
newBounds = new List <ComprehensionExpr.BoundedPool>();
}
else if (newBounds == e.Bounds)
{
// create a new list with the same elements, since the .Add operations below would otherwise add elements to the original e.Bounds
newBounds = new List <ComprehensionExpr.BoundedPool>(newBounds);
}
// conjoin all the new equalities to the range of the quantifier
foreach (var entry in usedSubstMap)
{
var eq = new BinaryExpr(e.tok, BinaryExpr.ResolvedOpcode.EqCommon, entry.Item2, entry.Item1);
newRange = newRange == null ? eq : new BinaryExpr(e.tok, BinaryExpr.ResolvedOpcode.And, eq, newRange);
newBoundVars.Add((BoundVar)entry.Item2.Var);
newBounds.Add(new ComprehensionExpr.ExactBoundedPool(entry.Item1));
}
QuantifierExpr newExpr;
if (expr is ForallExpr)
{
newExpr = new ForallExpr(e.tok, e.TypeArgs, newBoundVars, newRange, newTerm, newAttrs)
{
Bounds = newBounds
};
}
else
{
Contract.Assert(expr is ExistsExpr);
newExpr = new ExistsExpr(e.tok, e.TypeArgs, newBoundVars, newRange, newTerm, newAttrs)
{
Bounds = newBounds
};
}
usedSubstMap.Clear();
newExpr.Type = expr.Type;
return(newExpr);
}
return(base.Substitute(expr));
}
public RtlExp GhostExpressionRec(Expression exp, bool inRecSpec = false, bool inRequiresOrOld = false)
{
Util.Assert(!isPrinting);
exp = GetExp(exp);
StmtExpr stmtExpr = exp as StmtExpr;
IdentifierExpr idExp = exp as IdentifierExpr;
LiteralExpr literal = exp as LiteralExpr;
BinaryExpr binary = exp as BinaryExpr;
UnaryExpr unary = exp as UnaryExpr;
ITEExpr ite = exp as ITEExpr;
ExistsExpr existsExp = exp as ExistsExpr;
ForallExpr forallExp = exp as ForallExpr;
LetExpr letExp = exp as LetExpr;
MatchExpr matchExp = exp as MatchExpr;
OldExpr oldExp = exp as OldExpr;
FreshExpr freshExp = exp as FreshExpr;
FunctionCallExpr funCall = exp as FunctionCallExpr;
DatatypeValue dataVal = exp as DatatypeValue;
FieldSelectExpr fieldSelect = exp as FieldSelectExpr;
SeqSelectExpr seqSelect = exp as SeqSelectExpr;
SeqUpdateExpr seqUpdate = exp as SeqUpdateExpr;
SeqDisplayExpr seqDisplay = exp as SeqDisplayExpr;
Func <Expression, RtlExp> G = e => GhostExpression(e, inRecSpec, inRequiresOrOld);
if (stmtExpr != null)
{
if (stmtExprEnabled)
{
if (ignoreStmtExpr == 0)
{
AddGhostStatement(stmtExpr.S);
}
return(G(stmtExpr.E));
}
else
{
throw new Exception("not implemented: cannot handle statement expression here");
}
}
else if (idExp != null)
{
return(AsVar(idExp));
}
else if (literal != null && literal.Value is BigInteger)
{
return(new RtlInt((BigInteger)(literal.Value)));
}
else if (literal != null && literal.Value is bool)
{
return(new RtlLiteral((bool)(literal.Value) ? "true" : "false"));
}
else if (literal != null && literal.Value == null)
{
return(new RtlLiteral("ArrayOfInt(0 - 1, NO_ABS)"));
}
else if (literal != null && literal.Value is Microsoft.Basetypes.BigDec)
{
return(new RtlLiteral(((Microsoft.Basetypes.BigDec)literal.Value).ToDecimalString()));
}
else if (binary != null)
{
string op = null;
string internalOp = null;
CompileFunction compileFunction = this as CompileFunction;
string thisFuncName = (compileFunction == null) ? null : compileFunction.function.Name;
switch (binary.ResolvedOp)
{
case BinaryExpr.ResolvedOpcode.SeqEq:
return(new RtlApply(dafnySpec.GetSeqOperationName(AppType(binary.E0.Type), "Seq_Equal"),
new RtlExp[] { G(binary.E0), G(binary.E1) }));
case BinaryExpr.ResolvedOpcode.SeqNeq:
return(new RtlLiteral("(!" +
new RtlApply(dafnySpec.GetSeqOperationName(AppType(binary.E0.Type), "Seq_Equal"),
new RtlExp[] { G(binary.E0), G(binary.E1) }) + ")"));
case BinaryExpr.ResolvedOpcode.Concat:
return(new RtlApply(dafnySpec.GetSeqOperationName(AppType(binary.Type), "Seq_Append"),
new RtlExp[] { G(binary.E0), G(binary.E1) }));
}
if (binary.Op == BinaryExpr.Opcode.Exp)
{
binary = new BinaryExpr(binary.tok, BinaryExpr.Opcode.Imp, binary.E0, binary.E1);
}
switch (binary.Op)
{
case BinaryExpr.Opcode.Disjoint:
case BinaryExpr.Opcode.In:
case BinaryExpr.Opcode.NotIn:
throw new Exception("not implemented: binary operator '" + BinaryExpr.OpcodeString(binary.Op) + "'");
}
if (AppType(binary.E0.Type) is IntType && AppType(binary.E1.Type) is IntType)
{
switch (binary.Op)
{
case BinaryExpr.Opcode.Le: internalOp = "INTERNAL_le_boogie"; break;
case BinaryExpr.Opcode.Lt: internalOp = "INTERNAL_lt_boogie"; break;
case BinaryExpr.Opcode.Ge: internalOp = "INTERNAL_ge_boogie"; break;
case BinaryExpr.Opcode.Gt: internalOp = "INTERNAL_gt_boogie"; break;
case BinaryExpr.Opcode.Add: internalOp = "INTERNAL_add_boogie"; break;
case BinaryExpr.Opcode.Sub: internalOp = "INTERNAL_sub_boogie"; break;
case BinaryExpr.Opcode.Mul:
op = "*";
if (thisFuncName != "INTERNAL_mul")
{
internalOp = FunName("INTERNAL__mul");
}
break;
case BinaryExpr.Opcode.Div:
op = "div";
if (thisFuncName != "INTERNAL_div")
{
internalOp = FunName("INTERNAL__div");
}
break;
case BinaryExpr.Opcode.Mod:
op = "mod";
if (thisFuncName != "INTERNAL_mod")
{
internalOp = FunName("INTERNAL__mod");
}
break;
default:
op = BinaryExpr.OpcodeString(binary.Op);
break;
}
}
else
{
op = BinaryExpr.OpcodeString(binary.Op);
}
if (internalOp == null)
{
return(new RtlBinary(op, G(binary.E0), G(binary.E1)));
}
else
{
return(new RtlApply(internalOp, new RtlExp[]
{ G(binary.E0), G(binary.E1) }));
}
}
else if (unary != null && unary.Op == UnaryExpr.Opcode.Not)
{
return(new RtlLiteral("(!(" + G(unary.E) + "))"));
}
else if (unary != null && unary.Op == UnaryExpr.Opcode.SeqLength)
{
return(new RtlApply(dafnySpec.GetSeqOperationName(AppType(unary.E.Type), "Seq_Length"),
new RtlExp[] { G(unary.E) }));
}
else if (ite != null)
{
return(GhostIfThenElse(G(ite.Test), () => G(ite.Thn), () => G(ite.Els)));
}
else if (funCall != null)
{
switch (funCall.Function.Name)
{
case "left":
case "right":
case "relation":
case "public":
Util.Assert(funCall.Args.Count == 1);
return(new RtlApply(funCall.Function.Name, new RtlExp[] { G(funCall.Args[0]) }));
case "sizeof":
Util.Assert(funCall.Args.Count == 1);
return(new RtlApply(funCall.Function.Name + "##" + TypeString(AppType(funCall.Args[0].Type)),
new RtlExp[] { G(funCall.Args[0]) }));
case "INTERNAL_add_raw":
Util.Assert(funCall.Args.Count == 2);
return(new RtlBinary("+", G(funCall.Args[0]), G(funCall.Args[1])));
case "INTERNAL_sub_raw":
Util.Assert(funCall.Args.Count == 2);
return(new RtlBinary("-", G(funCall.Args[0]), G(funCall.Args[1])));
case "IntToReal":
Util.Assert(funCall.Args.Count == 1);
return(new RtlApply("real", new RtlExp[] { G(funCall.Args[0]) }));
case "RealToInt":
Util.Assert(funCall.Args.Count == 1);
return(new RtlApply("int", new RtlExp[] { G(funCall.Args[0]) }));
}
TypeApply app = dafnySpec.Compile_Function(funCall.Function,
funCall.TypeArgumentSubstitutions.ToDictionary(p => p.Key, p => AppType(p.Value)));
string name = FunName(SimpleName(app.AppName()));
string fullName = FunName(SimpleName(app.AppFullName()));
List <RtlExp> rtlArgs = funCall.Args.Select(G).ToList();
List <RtlExp> rtlReads = funCall.Function.Reads.Where(e => e.Field != null).ToList()
.ConvertAll(e => (RtlExp) new RtlVar(
GhostVar(e.FieldName), e.Field.IsGhost, AppType(e.Field.Type)));
rtlArgs = rtlReads.Concat(rtlArgs).ToList();
if (name.EndsWith("__INTERNAL__HEAP"))
{
name = name.Substring(0, name.Length - "__INTERNAL__HEAP".Length);
}
else if (DafnySpec.IsHeapFunction(funCall.Function))
{
rtlArgs.Insert(0, new RtlLiteral(inRequiresOrOld ? "$absMem_old" : "$absMem"));
}
if (Attributes.Contains(funCall.Function.Attributes, "opaque") &&
funCall.Function.Formals.Count + rtlReads.Count == 0)
{
rtlArgs.Insert(0, new RtlLiteral("true"));
}
if (fullName == recFunName)
{
name = fullName;
}
if (name == recFunName)
{
recCalls.Add(new List <RtlExp>(rtlArgs));
rtlArgs.Insert(0, new RtlApply("decreases_" + name, new List <RtlExp>(rtlArgs)));
rtlArgs.Insert(1, new RtlLiteral(inRecSpec ? "__unroll" : "__unroll + 1"));
name = "rec_" + name;
}
return(new RtlApply(name, rtlArgs));
}
else if (dataVal != null)
{
bool isSeq = dataVal.Type.TypeName(null).StartsWith("Seq<");
return(new RtlApply((isSeq ? "_" : "") + dafnySpec.Compile_Constructor(
dataVal.Type, dataVal.Ctor.Name, dataVal.InferredTypeArgs, typeApply.typeArgs).AppName(),
dataVal.Arguments.Select(G)));
}
else if (existsExp != null || forallExp != null)
{
QuantifierExpr qExp = (QuantifierExpr)exp;
bool isForall = forallExp != null;
var varTuples = qExp.BoundVars.Select(v => Tuple.Create(GhostVar(v.Name), v.IsGhost, v.Type));
var oldRenamer = PushRename(qExp.BoundVars.Select(v => v.Name));
var oldStmtExprEnabled = stmtExprEnabled;
stmtExprEnabled = false;
RtlExp rExp = new RtlLiteral((isForall ? "(forall " : "(exists ")
+ string.Join(", ", qExp.BoundVars.Select(v => GhostVar(v.Name) + ":" + TypeString(AppType(v.Type))))
+ " :: " + Triggers(qExp.Attributes, G) + " "
+ GetTypeWellFormedExp(varTuples.ToList(), isForall ? "==>" : "&&", G(qExp.Term)) + ")");
stmtExprEnabled = oldStmtExprEnabled;
PopRename(oldRenamer);
return(rExp);
}
else if (letExp != null)
{
List <RtlExp> rhss;
if (letExp.Exact)
{
rhss = letExp.RHSs.ConvertAll(e => G(e));
}
else if (letExp.LHSs.Count == 1 && LiteralExpr.IsTrue(letExp.RHSs[0]) && AppType(letExp.LHSs[0].Var.Type) is IntType)
{
rhss = new List <RtlExp> {
new RtlLiteral("0")
};
}
else
{
throw new Exception("not implemented: LetExpr: " + letExp);
}
return(GhostLet(exp.tok, letExp.LHSs.ConvertAll(lhs => lhs.Var), rhss, () => G(letExp.Body)));
}
else if (matchExp != null)
{
if (matchExp.MissingCases.Count != 0)
{
throw new Exception("not implemented: MatchExpr with missing cases: " + matchExp);
}
//- match src case c1(ps1) => e1 ... cn(psn) => en
//- -->
//- let x := src in
//- if x is c1 then let ps1 := ...x.f1... in e1 else
//- if x is c2 then let ps2 := ...x.f2... in e2 else
//- let ps3 := ...x.f3... in e3
var src = G(matchExp.Source);
var cases = matchExp.Cases;
string x = TempName();
Func <RtlExp> body = null;
for (int i = cases.Count; i > 0;)
{
i--;
MatchCaseExpr c = cases[i];
Func <List <RtlExp> > cRhss = () => c.Ctor.Formals.ConvertAll(f => (RtlExp) new RtlLiteral("("
+ f.Name + "#" + c.Ctor.Name + "(" + GhostVar(x) + "))"));
Func <RtlExp> ec = () => GhostLet(exp.tok, c.Arguments, cRhss(), () => G(c.Body));
if (body == null)
{
body = ec;
}
else
{
var prevBody = body;
body = () => GhostIfThenElse(new RtlLiteral("(" + GhostVar(x) + " is " + c.Ctor.Name + ")"),
ec, prevBody);
}
}
return(GhostLet(exp.tok, new List <BoundVar> {
new BoundVar(exp.tok, x, matchExp.Source.Type)
},
new List <RtlExp> {
src
}, body));
}
else if (oldExp != null)
{
return(new RtlLiteral("old(" + GhostExpression(oldExp.E, inRecSpec, true) + ")"));
}
else if (freshExp != null)
{
Util.Assert(DafnySpec.IsArrayType(freshExp.E.Type));
string abs = G(freshExp.E) + ".arrAbs";
return(new RtlLiteral("(heap_old.absData[" + abs + "] is AbsNone)"));
}
else if (fieldSelect != null && fieldSelect.FieldName.EndsWith("?"))
{
string constructor = fieldSelect.FieldName.Substring(0, fieldSelect.FieldName.Length - 1);
constructor = dafnySpec.Compile_Constructor(fieldSelect.Obj.Type, constructor, null, typeApply.typeArgs).AppName();
bool isSeq = fieldSelect.Obj.Type.TypeName(null).StartsWith("Seq<");
return(isSeq
? new RtlLiteral("is_" + constructor + "(" + G(fieldSelect.Obj) + ")")
: new RtlLiteral("((" + G(fieldSelect.Obj) + ") is " + constructor + ")"));
}
else if (fieldSelect != null && !fieldSelect.Field.IsStatic && AppType(fieldSelect.Obj.Type) is UserDefinedType &&
fieldSelect.Field is DatatypeDestructor)
{
DatatypeDestructor field = (DatatypeDestructor)fieldSelect.Field;
string constructor = dafnySpec.Compile_Constructor(fieldSelect.Obj.Type,
field.EnclosingCtor.Name, null, typeApply.typeArgs).AppName();
bool isSeq = fieldSelect.Obj.Type.TypeName(null).StartsWith("Seq<");
return(new RtlLiteral("(" + fieldSelect.FieldName + (isSeq ? "_" : "#") + constructor
+ "(" + G(fieldSelect.Obj) + "))"));
}
else if (fieldSelect != null && DafnySpec.IsArrayType(AppType(fieldSelect.Obj.Type)) &&
fieldSelect.FieldName == "Length")
{
return(new RtlLiteral("(Arr_Length(" + G(fieldSelect.Obj) + "))"));
}
else if (fieldSelect != null && fieldSelect.Obj is ImplicitThisExpr)
{
//- we don't support objects yet, so interpret this as a global variable
return(new RtlVar(GhostVar(fieldSelect.FieldName), true, fieldSelect.Type));
}
else if (seqSelect != null)
{
if (seqSelect.SelectOne && DafnySpec.IsArrayType(AppType(seqSelect.Seq.Type)))
{
return(new RtlExpComputed(e => "fun_INTERNAL__array__elems__index("
+ (inRequiresOrOld ? "$absMem_old" : "$absMem") + "[" + e.args[0] + ".arrAbs], ("
+ e.args[1] + "))", new RtlExp[] { G(seqSelect.Seq), G(seqSelect.E0) }));
}
else if (seqSelect.SelectOne)
{
return(new RtlApply(dafnySpec.GetSeqOperationName(AppType(seqSelect.Seq.Type), "Seq_Index"),
new RtlExp[] { G(seqSelect.Seq), G(seqSelect.E0) }));
}
else
{
RtlExp seq = G(seqSelect.Seq);
if (DafnySpec.IsArrayType(AppType(seqSelect.Seq.Type)))
{
seq = new RtlApply(FunName("Seq__FromArray"), new RtlExp[] {
new RtlLiteral(inRequiresOrOld ? "$absMem_old" : "$absMem"), seq
});
}
if (seqSelect.E1 != null)
{
seq = new RtlApply(dafnySpec.GetSeqOperationName(AppType(seqSelect.Type), "Seq_Take"),
new RtlExp[] { seq, G(seqSelect.E1) });
}
if (seqSelect.E0 != null)
{
seq = new RtlApply(dafnySpec.GetSeqOperationName(AppType(seqSelect.Type), "Seq_Drop"),
new RtlExp[] { seq, G(seqSelect.E0) });
}
return(seq);
}
}
else if (seqUpdate != null)
{
if (seqUpdate.ResolvedUpdateExpr != null)
{
return(GhostExpressionRec(seqUpdate.ResolvedUpdateExpr, inRecSpec, inRequiresOrOld));
}
return(new RtlApply(dafnySpec.GetSeqOperationName(AppType(seqUpdate.Seq.Type), "Seq_Update"),
new RtlExp[] { G(seqUpdate.Seq), G(seqUpdate.Index), G(seqUpdate.Value) }));
}
else if (seqDisplay != null)
{
RtlExp seq = new RtlApply(dafnySpec.GetSeqOperationName(AppType(seqDisplay.Type), "Seq_Empty"), new RtlExp[0]);
foreach (Expression ei in seqDisplay.Elements)
{
seq = new RtlApply(dafnySpec.GetSeqOperationName(AppType(seqDisplay.Type), "Seq_Build"),
new RtlExp[] { seq, G(ei) });
}
return(seq);
}
else
{
throw new Exception("not implemented: " + exp);
}
}
public FunctionCollector()
{
functionsUsed = new List <Tuple <Function, ExistsExpr> >();
existentialExpr = null;
}
// ExistsExpr
public static int GetNumberOfChildren(this ExistsExpr e)
{
return(1);
}
