public RtlExp GhostLet(Microsoft.Boogie.IToken tok, List <BoundVar> lhss, List <RtlExp> rhss,
Func <RtlExp> body)
{
if (stmtExprEnabled && ignoreStmtExpr == 0)
{
var oldRenamer1 = PushRename();
for (int i = 0; i < lhss.Count; i++)
{
var lhs = lhss[i];
var rhs = rhss[i];
AddGhostVarDecl(lhs.Name, lhs.Type, true);
MoveGhost(new RtlVar(GhostVar(lhs.Name), true, AppType(lhs.Type)), rhs);
}
body();
PopRename(oldRenamer1);
}
var oldRenamer2 = PushRename();
lhss.ForEach(e => AddRename(e.Name));
ignoreStmtExpr++;
RtlExp rExp = new RtlLiteral("("
+ String.Concat(lhss.Zip(rhss, (lhs, rhs) =>
"let " + GhostVar(lhs.Name) + ":" + TypeString(AppType(lhs.Type))
+ " := (" + rhs + ") in "))
+ " (" + body() + "))");
ignoreStmtExpr--;
PopRename(oldRenamer2);
return(rExp);
}
public virtual void AddResolvedGhostStatement(Statement stmt)
{
BlockStmt block = stmt as BlockStmt;
IfStmt ifStmt = stmt as IfStmt;
AssertStmt assertStmt = stmt as AssertStmt;
AssignStmt assignStmt = stmt as AssignStmt;
CallStmt callStmt = stmt as CallStmt;
VarDecl varDecl = stmt as VarDecl;
CalcStmt calcStmt = stmt as CalcStmt;
ForallStmt forallStmt = stmt as ForallStmt;
AssignSuchThatStmt existsStmt = stmt as AssignSuchThatStmt;
if (block != null)
{
var oldRenamer = PushRename();
block.Body.ForEach(AddGhostStatement);
PopRename(oldRenamer);
}
else if (varDecl != null)
{
AddGhostVarDecl(varDecl.Name, varDecl.Type, varDecl.IsGhost);
}
else if (minVerify)
{
return;
}
else if (assignStmt != null)
{
ExprRhs expRhs = assignStmt.Rhs as ExprRhs;
if (expRhs != null)
{
FieldSelectExpr fieldSelect = assignStmt.Lhs as FieldSelectExpr;
RtlVar destVar;
if (fieldSelect != null)
{
destVar = new RtlVar(GhostVar(fieldSelect.FieldName), true, fieldSelect.Type);
}
else
{
destVar = AsVar(assignStmt.Lhs);
Util.Assert(destVar != null);
}
stmts.Add(new RtlGhostMove(new RtlVar[] { destVar },
new RtlExp[] { GhostExpression(expRhs.Expr) }));
}
else
{
throw new Exception("not implemented: " + assignStmt.Rhs);
}
}
else if (callStmt != null)
{
AddGhostCall(callStmt.Lhs.ConvertAll(AsVar), callStmt.Args,
dafnySpec.Compile_Method(callStmt.Method,
callStmt.TypeArgumentSubstitutions.ToDictionary(p => p.Key, p => AppType(p.Value))),
DafnySpec.IsHeapMethod(callStmt.Method));
SymdiffLinearityPoint();
}
else if (ifStmt != null)
{
stmts.Add(new RtlGhostStmtComputed(s => "if (" + s.args[0] + ") {",
new RtlExp[] { GhostExpression(ifStmt.Guard) }));
Indent();
AddGhostStatement(ifStmt.Thn);
Unindent();
stmts.Add(new RtlGhostStmtComputed(s => "}", new RtlExp[0]));
if (ifStmt.Els != null)
{
stmts.Add(new RtlGhostStmtComputed(s => "if (" + s.args[0] + ") {",
new RtlExp[] {
GhostExpression(new UnaryExpr(Bpl.Token.NoToken, UnaryExpr.Opcode.Not, ifStmt.Guard))
}));
Indent();
AddGhostStatement(ifStmt.Els);
Unindent();
stmts.Add(new RtlGhostStmtComputed(s => "}", new RtlExp[0]));
}
}
else if (assertStmt != null)
{
stmts.Add(new RtlAssert(GhostExpression(assertStmt.Expr)));
}
else if (forallStmt != null)
{
var oldRenamer = PushRename(forallStmt.BoundVars.Select(v => v.Name));
RtlExp ens = new RtlLiteral("true");
foreach (var e in forallStmt.Ens)
{
ens = new RtlBinary("&&", ens, GhostExpression(e.E));
}
RtlExp range = (forallStmt.Range == null) ? new RtlLiteral("true")
: GhostExpression(forallStmt.Range);
List <RtlExp> wellFormed = GetTypeWellFormed(forallStmt.BoundVars.
Select(x => Tuple.Create(GhostVar(x.Name), x.IsGhost, x.Type)).ToList());
wellFormed.ForEach(e => range = new RtlBinary("&&", e, range));
ens = new RtlBinary("==>", range, ens);
string vars = String.Join(", ", forallStmt.BoundVars.Select(x => GhostVar(x.Name) + ":" +
TypeString(AppType(x.Type))));
stmts.Add(new RtlGhostStmtComputed(s => "forall " + vars + "::(" + s.args[0] + ")",
new List <RtlExp> {
ens
}));
stmts.Add(new RtlGhostStmtComputed(s => "{", new RtlExp[0]));
Indent();
stmts.Add(PushForall());
stmts.Add(new RtlGhostStmtComputed(s => "if (" + s.args[0] + ")",
new List <RtlExp> {
range
}));
stmts.Add(new RtlGhostStmtComputed(s => "{", new RtlExp[0]));
Indent();
AddGhostStatement(forallStmt.Body);
foreach (var e in forallStmt.Ens)
{
stmts.Add(new RtlAssert(GhostExpression(e.E)));
}
PopForall();
Unindent();
stmts.Add(new RtlGhostStmtComputed(s => "}", new RtlExp[0]));
Unindent();
stmts.Add(new RtlGhostStmtComputed(s => "}", new RtlExp[0]));
PopRename(oldRenamer);
}
else if (existsStmt != null)
{
List <RtlStmt> assigns = new List <RtlStmt>();
List <RtlVar> tmps = new List <RtlVar>();
List <Tuple <string, bool, Type> > varTuples = new List <Tuple <string, bool, Type> >();
var oldRenamer = PushRename();
foreach (var lhs in existsStmt.Lhss)
{
IdentifierExpr idExp = lhs.Resolved as IdentifierExpr;
RtlVar origVar = AsVar(lhs);
AddRename(idExp.Name);
RtlVar renameVar = AsVar(lhs);
tmps.Add(renameVar);
varTuples.Add(Tuple.Create(renameVar.ToString(), true, idExp.Type));
assigns.Add(new RtlGhostMove(new RtlVar[] { origVar },
new RtlExp[] { renameVar }));
}
string vars = String.Join(", ", tmps.Select(x => x.getName() + ":" + TypeString(AppType(x.type))));
stmts.Add(new RtlGhostStmtComputed(s => "exists " + vars + "::(" + s.args[0] + ");",
new List <RtlExp> {
GetTypeWellFormedExp(varTuples.ToList(), "&&", GhostExpression(existsStmt.Expr))
}));
stmts.AddRange(assigns);
PopRename(oldRenamer);
}
else if (calcStmt != null)
{
Util.Assert(calcStmt.Steps.Count == calcStmt.Hints.Count);
CalcStmt.BinaryCalcOp binOp = calcStmt.Op as CalcStmt.BinaryCalcOp;
bool isImply = binOp != null && binOp.Op == BinaryExpr.Opcode.Imp && calcStmt.Steps.Count > 0;
if (isImply)
{
stmts.Add(new RtlGhostStmtComputed(s => "if (" + s.args[0] + ")",
new RtlExp[] { GhostExpression(CalcStmt.Lhs(calcStmt.Steps[0])) }));
stmts.Add(new RtlGhostStmtComputed(s => "{", new RtlExp[0]));
Indent();
}
var stepCount = calcStmt.Hints.Last().Body.Count == 0 ? calcStmt.Steps.Count - 1 : calcStmt.Steps.Count;
for (int i = 0; i < stepCount; i++)
{
if (calcStmt.Hints[i] == null)
{
stmts.Add(new RtlAssert(GhostExpression(calcStmt.Steps[i])));
}
else
{
stmts.Add(new RtlGhostStmtComputed(s => "forall::(" + s.args[0] + ")",
new List <RtlExp> {
GhostExpression(calcStmt.Steps[i])
}));
stmts.Add(new RtlGhostStmtComputed(s => "{", new RtlExp[0]));
Indent();
var dict = new Dictionary <string, RtlVar>();
stmts.Add(new RtlGhostStmtComputed(s => String.Concat(dict.Values.Select(
x => "var " + x.x + ":" + TypeString(x.type) + ";")),
new RtlExp[0]));
forallVars.Add(dict);
AddGhostStatement(calcStmt.Hints[i]);
forallVars.RemoveAt(forallVars.Count - 1);
Unindent();
stmts.Add(new RtlGhostStmtComputed(s => "}", new RtlExp[0]));
}
}
if (isImply)
{
Unindent();
stmts.Add(new RtlGhostStmtComputed(s => "}", new RtlExp[0]));
}
}
else
{
throw new Exception("not implemented in ghost methods: " + stmt);
}
}
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 virtual void AddResolvedGhostStatement(Statement stmt, Attributes attrs)
{
BlockStmt block = stmt as BlockStmt;
IfStmt ifStmt = stmt as IfStmt;
AssertStmt assertStmt = stmt as AssertStmt;
AssignStmt assignStmt = stmt as AssignStmt;
CallStmt callStmt = stmt as CallStmt;
VarDeclStmt varDecl = stmt as VarDeclStmt;
CalcStmt calcStmt = stmt as CalcStmt;
ForallStmt forallStmt = stmt as ForallStmt;
AssignSuchThatStmt existsStmt = stmt as AssignSuchThatStmt;
if (block != null)
{
var oldRenamer = PushRename();
block.Body.ForEach(s => AddGhostStatement(s, attrs));
PopRename(oldRenamer);
}
else if (varDecl != null)
{
foreach (var varLocal in varDecl.Locals) {
AddGhostVarDecl(varLocal.Name, varLocal.Type, varLocal.IsGhost);
}
if (varDecl.Update != null) {
Util.Assert(varDecl.Update is UpdateStmt || varDecl.Update is AssignSuchThatStmt);
AddGhostStatement((Statement)varDecl.Update, attrs);
//Util.Assert(varDecl.Update.Lhss.Count() == 1);
//var destVar = AsVar(varDecl.Update.Lhss[0]);
//Util.Assert(destVar != null);
//ExprRhs expRhs = ((UpdateStmt)varDecl.Update).Rhss[0] as ExprRhs;
//if (expRhs != null) {
// stmts.Add(new RtlGhostMove(new RtlVar[] { destVar },
// new RtlExp[] { GhostExpression(expRhs.Expr) }));
//} else {
// throw new Exception("not implemented: " + ((UpdateStmt)varDecl.Update).Rhss[0]);
//}
}
}
else if (minVerify)
{
return;
}
else if (assignStmt != null)
{
ExprRhs expRhs = assignStmt.Rhs as ExprRhs;
if (expRhs != null)
{
MemberSelectExpr memberSelect = assignStmt.Lhs as MemberSelectExpr;
RtlVar destVar;
if (memberSelect != null && memberSelect.Member is Field)
{
// assume that this is a global variable; we don't support objects yet
destVar = new RtlVar(GhostVar(memberSelect.MemberName), true, memberSelect.Type);
}
else
{
destVar = AsVar(assignStmt.Lhs);
Util.Assert(destVar != null);
}
stmts.Add(new RtlGhostMove(new RtlVar[] { destVar },
new RtlExp[] { GhostExpression(expRhs.Expr) }));
}
else
{
throw new Exception("not implemented: " + assignStmt.Rhs);
}
}
else if (callStmt != null)
{
var extraTypeargs = GetTypeArgs(attrs);
var extraTypeargsDict = extraTypeargs.Select((t,index) => Tuple.Create(new TypeParameter(callStmt.Tok, "Fake" + index),t)).ToDictionary(tuple => tuple.Item1, tuple => tuple.Item2);
var subst = callStmt.MethodSelect.TypeArgumentSubstitutions().Concat(extraTypeargsDict);
AddGhostCall(callStmt.Lhs.ConvertAll(AsVar), callStmt.Args,
dafnySpec.Compile_Method((Method)callStmt.MethodSelect.Member,
subst.ToDictionary(p => p.Key, p => AppType(p.Value)),
extraTypeargsDict.Keys.ToList()),
DafnySpec.IsHeapMethod((Method)callStmt.MethodSelect.Member));
SymdiffLinearityPoint();
}
else if (ifStmt != null)
{
stmts.Add(new RtlGhostStmtComputed(s => "if (" + s.args[0] + ") {",
new RtlExp[] { GhostExpression(ifStmt.Guard) }));
Indent();
AddGhostStatement(ifStmt.Thn, attrs);
Unindent();
stmts.Add(new RtlGhostStmtComputed(s => "}", new RtlExp[0]));
if (ifStmt.Els != null)
{
stmts.Add(new RtlGhostStmtComputed(s => "if (" + s.args[0] + ") {",
new RtlExp[] {
GhostExpression(new UnaryOpExpr(Bpl.Token.NoToken, UnaryOpExpr.Opcode.Not, ifStmt.Guard)) }));
Indent();
AddGhostStatement(ifStmt.Els, attrs);
Unindent();
stmts.Add(new RtlGhostStmtComputed(s => "}", new RtlExp[0]));
}
}
else if (assertStmt != null)
{
stmts.Add(new RtlAssert(GhostExpression(assertStmt.Expr)));
}
else if (forallStmt != null)
{
var oldRenamer = PushRename(forallStmt.BoundVars.Select(v => v.Name));
RtlExp ens = new RtlLiteral("true");
foreach (var e in forallStmt.Ens)
{
ens = new RtlBinary("&&", ens, GhostExpression(e.E));
}
RtlExp range = (forallStmt.Range == null) ? new RtlLiteral("true")
: GhostExpression(forallStmt.Range);
List<RtlExp> wellFormed = GetTypeWellFormed(forallStmt.BoundVars.
Select(x => Tuple.Create(GhostVar(x.Name), x.IsGhost, x.Type)).ToList());
wellFormed.ForEach(e => range = new RtlBinary("&&", e, range));
ens = new RtlBinary("==>", range, ens);
string vars = String.Join(", ", forallStmt.BoundVars.Select(x => GhostVar(x.Name) + ":" +
TypeString(AppType(x.Type))));
stmts.Add(new RtlGhostStmtComputed(s => "forall " + vars + "::(" + s.args[0] + ")",
new List<RtlExp> { ens }));
stmts.Add(new RtlGhostStmtComputed(s => "{", new RtlExp[0]));
Indent();
stmts.Add(PushForall());
stmts.Add(new RtlGhostStmtComputed(s => "if (" + s.args[0] + ")",
new List<RtlExp> { range }));
stmts.Add(new RtlGhostStmtComputed(s => "{", new RtlExp[0]));
Indent();
AddGhostStatement(forallStmt.Body, attrs);
foreach (var e in forallStmt.Ens)
{
stmts.Add(new RtlAssert(GhostExpression(e.E)));
}
PopForall();
Unindent();
stmts.Add(new RtlGhostStmtComputed(s => "}", new RtlExp[0]));
Unindent();
stmts.Add(new RtlGhostStmtComputed(s => "}", new RtlExp[0]));
PopRename(oldRenamer);
}
else if (existsStmt != null)
{
List<RtlStmt> assigns = new List<RtlStmt>();
List<RtlVar> tmps = new List<RtlVar>();
List<Tuple<string,bool,Type>> varTuples = new List<Tuple<string,bool,Type>>();
var oldRenamer = PushRename();
foreach (var lhs in existsStmt.Lhss)
{
IdentifierExpr idExp = lhs.Resolved as IdentifierExpr;
RtlVar origVar = AsVar(lhs);
AddRename(idExp.Name);
RtlVar renameVar = AsVar(lhs);
tmps.Add(renameVar);
varTuples.Add(Tuple.Create(renameVar.ToString(), true, idExp.Type));
assigns.Add(new RtlGhostMove(new RtlVar[] { origVar },
new RtlExp[] { renameVar }));
}
string vars = String.Join(", ", tmps.Select(x => x.getName() + ":" + TypeString(AppType(x.type))));
stmts.Add(new RtlGhostStmtComputed(s => "exists " + vars + "::(" + s.args[0] + ");",
new List<RtlExp> {
GetTypeWellFormedExp(varTuples.ToList(), "&&", GhostExpression(existsStmt.Expr)) }));
stmts.AddRange(assigns);
PopRename(oldRenamer);
}
else if (calcStmt != null)
{
Util.Assert(calcStmt.Steps.Count == calcStmt.Hints.Count);
CalcStmt.BinaryCalcOp binOp = calcStmt.Op as CalcStmt.BinaryCalcOp;
bool isImply = binOp != null && binOp.Op == BinaryExpr.Opcode.Imp && calcStmt.Steps.Count > 0;
if (isImply)
{
stmts.Add(new RtlGhostStmtComputed(s => "if (" + s.args[0] + ")",
new RtlExp[] { GhostExpression(CalcStmt.Lhs(calcStmt.Steps[0])) }));
stmts.Add(new RtlGhostStmtComputed(s => "{", new RtlExp[0]));
Indent();
}
var stepCount = calcStmt.Hints.Last().Body.Count == 0 ? calcStmt.Steps.Count - 1 : calcStmt.Steps.Count;
for (int i = 0; i < stepCount; i++)
{
if (calcStmt.Hints[i] == null)
{
stmts.Add(new RtlAssert(GhostExpression(calcStmt.Steps[i])));
}
else
{
stmts.Add(new RtlGhostStmtComputed(s => "forall::(" + s.args[0] + ")",
new List<RtlExp> { GhostExpression(calcStmt.Steps[i]) }));
stmts.Add(new RtlGhostStmtComputed(s => "{", new RtlExp[0]));
Indent();
var dict = new Dictionary<string,RtlVar>();
stmts.Add(new RtlGhostStmtComputed(s => String.Concat(dict.Values.Select(
x => "var " + x.x + ":" + TypeString(x.type) + ";")),
new RtlExp[0]));
forallVars.Add(dict);
AddGhostStatement(calcStmt.Hints[i], attrs);
forallVars.RemoveAt(forallVars.Count - 1);
Unindent();
stmts.Add(new RtlGhostStmtComputed(s => "}", new RtlExp[0]));
}
}
if (isImply)
{
Unindent();
stmts.Add(new RtlGhostStmtComputed(s => "}", new RtlExp[0]));
}
}
else
{
throw new Exception("not implemented in ghost methods: " + stmt);
}
}
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;
FunctionCallExpr funCall = exp as FunctionCallExpr;
DatatypeValue dataVal = exp as DatatypeValue;
MemberSelectExpr memberSelect = exp as MemberSelectExpr;
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, null);
}
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) {
if (unary is UnaryOpExpr) {
UnaryOpExpr unaryOp = (UnaryOpExpr)unary;
if (unaryOp.Op == UnaryOpExpr.Opcode.Not) {
return new RtlLiteral("(!(" + G(unaryOp.E) + "))");
} else if (unaryOp.Op == UnaryOpExpr.Opcode.Cardinality) {
return new RtlApply(dafnySpec.GetSeqOperationName(AppType(unaryOp.E.Type), "Seq_Length"),
new RtlExp[] { G(unaryOp.E) });
} else if (unaryOp.Op == UnaryOpExpr.Opcode.Fresh) {
Util.Assert(DafnySpec.IsArrayType(unaryOp.E.Type));
string abs = G(unaryOp.E) + ".arrAbs";
return new RtlLiteral("(heap_old.absData[" + abs + "] is AbsNone)");
} else {
throw new Exception("not implemented: " + exp);
}
} else if (unary is ConversionExpr) {
var e = (ConversionExpr)unary;
var fromInt = e.E.Type.IsNumericBased(Type.NumericPersuation.Int);
var toInt = e.ToType.IsNumericBased(Type.NumericPersuation.Int);
if (fromInt && !toInt) {
return new RtlApply("real", new RtlExp[] { G(e.E) });
} else if (!fromInt && toInt) {
return new RtlApply("int", new RtlExp[] { G(e.E) });
} else {
Util.Assert(fromInt == toInt);
return GhostExpressionRec(e.E, inRecSpec, inRequiresOrOld);
}
} else {
throw new Exception("not implemented: " + exp);
}
}
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]));
}
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 (memberSelect != null && memberSelect.MemberName.EndsWith("?"))
{
string constructor = memberSelect.MemberName.Substring(0, memberSelect.MemberName.Length - 1);
constructor = dafnySpec.Compile_Constructor(memberSelect.Obj.Type, constructor, null, typeApply.typeArgs).AppName();
bool isSeq = memberSelect.Obj.Type.TypeName(null).StartsWith("Seq<");
return isSeq
? new RtlLiteral("is_" + constructor + "(" + G(memberSelect.Obj) + ")")
: new RtlLiteral("((" + G(memberSelect.Obj) + ") is " + constructor + ")");
}
else if (memberSelect != null && memberSelect.Member is Field && !memberSelect.Member.IsStatic && AppType(memberSelect.Obj.Type) is UserDefinedType
&& memberSelect.Member is DatatypeDestructor)
{
DatatypeDestructor field = (DatatypeDestructor) memberSelect.Member;
string constructor = dafnySpec.Compile_Constructor(memberSelect.Obj.Type,
field.EnclosingCtor.Name, null, typeApply.typeArgs).AppName();
bool isSeq = memberSelect.Obj.Type.TypeName(null).StartsWith("Seq<");
return new RtlLiteral("(" + memberSelect.MemberName + (isSeq ? "_" : "#") + constructor
+ "(" + G(memberSelect.Obj) + "))");
}
else if (memberSelect != null && memberSelect.Member is Field && DafnySpec.IsArrayType(AppType(memberSelect.Obj.Type))
&& memberSelect.MemberName == "Length")
{
return new RtlLiteral("(Arr_Length(" + G(memberSelect.Obj) + "))");
}
else if (memberSelect != null && memberSelect.Member is Field && memberSelect.Obj is ImplicitThisExpr)
{
//- we don't support objects yet, so interpret this as a global variable
return new RtlVar(GhostVar(memberSelect.MemberName), true, memberSelect.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 RtlExp GhostLet(Microsoft.Boogie.IToken tok, List<BoundVar> lhss, List<RtlExp> rhss,
Func<RtlExp> body)
{
if (stmtExprEnabled && ignoreStmtExpr == 0)
{
var oldRenamer1 = PushRename();
for (int i = 0; i < lhss.Count; i++)
{
var lhs = lhss[i];
var rhs = rhss[i];
AddGhostVarDecl(lhs.Name, lhs.Type, true);
MoveGhost(new RtlVar(GhostVar(lhs.Name), true, AppType(lhs.Type)), rhs);
}
body();
PopRename(oldRenamer1);
}
var oldRenamer2 = PushRename();
lhss.ForEach(e => AddRename(e.Name));
ignoreStmtExpr++;
RtlExp rExp = new RtlLiteral("("
+ String.Concat(lhss.Zip(rhss, (lhs, rhs) =>
"let " + GhostVar(lhs.Name) + ":" + TypeString(AppType(lhs.Type))
+ " := (" + rhs + ") in "))
+ " (" + body() + "))");
ignoreStmtExpr--;
PopRename(oldRenamer2);
return rExp;
}
