protected override void VisitOneStmt(Statement stmt)
{
if (stmt is ForallStmt)
{
ForallStmt s = (ForallStmt)stmt;
if (s.ForallExpressions != null)
{
foreach (Expression expr in s.ForallExpressions)
{
VisitOneExpr(expr);
}
}
}
}
protected override bool VisitOneStmt(Statement stmt, ref OldExpr /*?*/ st)
{
if (stmt is ForallStmt)
{
ForallStmt s = (ForallStmt)stmt;
if (s.ForallExpressions != null)
{
foreach (Expression expr in s.ForallExpressions)
{
VisitOneExpr(expr, ref st);
}
}
}
return(true);
}
public virtual void Visit(ForallStmt forAllStatement)
{
VisitNullableAttributes(forAllStatement.Attributes);
VisitNullableStatement(forAllStatement.Body);
}
void ForallStmt(out Statement/*!*/ s)
{
Contract.Ensures(Contract.ValueAtReturn(out s) != null);
IToken/*!*/ x = Token.NoToken;
List<BoundVar> bvars = null;
Attributes attrs = null;
Expression range = null;
var ens = new List<MaybeFreeExpression/*!*/>();
bool isFree;
Expression/*!*/ e;
BlockStmt block = null;
IToken bodyStart, bodyEnd;
IToken tok = Token.NoToken;
if (la.kind == 103) {
Get();
x = t; tok = x;
} else if (la.kind == 104) {
Get();
x = t;
errors.Warning(t, "the 'parallel' keyword has been deprecated; the comprehension statement now uses the keyword 'forall' (and the parentheses around the bound variables are now optional)");
} else SynErr(190);
if (la.kind == _openparen) {
Expect(50);
if (la.kind == 1) {
QuantifierDomain(out bvars, out attrs, out range);
}
Expect(51);
} else if (StartOf(24)) {
if (la.kind == _ident) {
QuantifierDomain(out bvars, out attrs, out range);
}
} else SynErr(191);
if (bvars == null) { bvars = new List<BoundVar>(); }
if (range == null) { range = new LiteralExpr(x, true); }
while (la.kind == 88 || la.kind == 89) {
isFree = false;
if (la.kind == 88) {
Get();
isFree = true;
errors.Warning(t, "the 'free' keyword is soon to be deprecated");
}
Expect(89);
Expression(out e, false, true);
ens.Add(new MaybeFreeExpression(e, isFree));
OldSemi();
tok = t;
}
if (la.kind == _lbrace) {
BlockStmt(out block, out bodyStart, out bodyEnd);
}
if (DafnyOptions.O.DisallowSoundnessCheating && block == null && 0 < ens.Count) {
SemErr(t, "a forall statement with an ensures clause must have a body");
}
if (block != null) {
tok = block.EndTok;
}
s = new ForallStmt(x, tok, bvars, attrs, range, ens, block);
}
private void FindRemovableTypesInForallStmt(ForallStmt forall, Method method, WildCardDecreases wildCardParent, ClassDecl classDecl)
{
FindRemovableTypesInStatement(forall.Body, forall, method, wildCardParent, classDecl);
}
public virtual Statement CloneStmt(Statement stmt) {
if (stmt == null) {
return null;
}
Statement r;
if (stmt is AssertStmt) {
var s = (AssertStmt)stmt;
r = new AssertStmt(Tok(s.Tok), Tok(s.EndTok), CloneExpr(s.Expr), null);
} else if (stmt is AssumeStmt) {
var s = (AssumeStmt)stmt;
r = new AssumeStmt(Tok(s.Tok), Tok(s.EndTok), CloneExpr(s.Expr), null);
} else if (stmt is TacticInvariantStmt) {
var s = (TacticInvariantStmt)stmt;
r = new TacticInvariantStmt(Tok(s.Tok), Tok(s.EndTok), CloneExpr(s.Expr), null, s.IsObjectLevel);
} else if (stmt is TacticAssertStmt) {
var s = (TacticAssertStmt)stmt;
r = new TacticAssertStmt(Tok(s.Tok), Tok(s.EndTok), CloneExpr(s.Expr), null, s.IsObjectLevel);
} else if (stmt is PrintStmt) {
var s = (PrintStmt)stmt;
r = new PrintStmt(Tok(s.Tok), Tok(s.EndTok), s.Args.ConvertAll(CloneExpr));
} else if (stmt is BreakStmt) {
var s = (BreakStmt)stmt;
if (s.TargetLabel != null) {
r = new BreakStmt(Tok(s.Tok), Tok(s.EndTok), s.TargetLabel);
} else {
r = new BreakStmt(Tok(s.Tok), Tok(s.EndTok), s.BreakCount);
}
} else if (stmt is ReturnStmt) {
var s = (ReturnStmt)stmt;
r = new ReturnStmt(Tok(s.Tok), Tok(s.EndTok), s.rhss == null ? null : s.rhss.ConvertAll(CloneRHS));
} else if (stmt is YieldStmt) {
var s = (YieldStmt)stmt;
r = new YieldStmt(Tok(s.Tok), Tok(s.EndTok), s.rhss == null ? null : s.rhss.ConvertAll(CloneRHS));
} else if (stmt is AssignStmt) {
var s = (AssignStmt)stmt;
r = new AssignStmt(Tok(s.Tok), Tok(s.EndTok), CloneExpr(s.Lhs), CloneRHS(s.Rhs));
} else if (stmt is BlockStmt) {
r = CloneBlockStmt((BlockStmt)stmt);
} else if (stmt is IfStmt) {
var s = (IfStmt)stmt;
r = new IfStmt(Tok(s.Tok), Tok(s.EndTok), s.IsExistentialGuard, CloneExpr(s.Guard), CloneBlockStmt(s.Thn), CloneStmt(s.Els));
} else if (stmt is AlternativeStmt) {
var s = (AlternativeStmt)stmt;
r = new AlternativeStmt(Tok(s.Tok), Tok(s.EndTok), s.Alternatives.ConvertAll(CloneGuardedAlternative));
} else if (stmt is WhileStmt) {
var s = (WhileStmt)stmt;
r = new WhileStmt(Tok(s.Tok), Tok(s.EndTok), CloneExpr(s.Guard), s.Invariants.ConvertAll(CloneMayBeFreeExpr), CloneSpecExpr(s.Decreases), CloneSpecFrameExpr(s.Mod), CloneBlockStmt(s.Body));
((WhileStmt)r).TacAps = s.TacAps;
} else if (stmt is AlternativeLoopStmt) {
var s = (AlternativeLoopStmt)stmt;
r = new AlternativeLoopStmt(Tok(s.Tok), Tok(s.EndTok), s.Invariants.ConvertAll(CloneMayBeFreeExpr), CloneSpecExpr(s.Decreases), CloneSpecFrameExpr(s.Mod), s.Alternatives.ConvertAll(CloneGuardedAlternative));
} else if (stmt is ForallStmt) {
var s = (ForallStmt)stmt;
r = new ForallStmt(Tok(s.Tok), Tok(s.EndTok), s.BoundVars.ConvertAll(CloneBoundVar), null, CloneExpr(s.Range), s.Ens.ConvertAll(CloneMayBeFreeExpr), CloneStmt(s.Body));
if (s.ForallExpressions != null) {
((ForallStmt)r).ForallExpressions = s.ForallExpressions.ConvertAll(CloneExpr);
}
} else if (stmt is CalcStmt) {
var s = (CalcStmt)stmt;
// calc statements have the unusual property that the last line is duplicated. If that is the case (which
// we expect it to be here), we share the clone of that line as well.
var lineCount = s.Lines.Count;
var lines = new List<Expression>(lineCount);
for (int i = 0; i < lineCount; i++) {
lines.Add(i == lineCount - 1 && 2 <= lineCount && s.Lines[i] == s.Lines[i - 1] ? lines[i - 1] : CloneExpr(s.Lines[i]));
}
Contract.Assert(lines.Count == lineCount);
r = new CalcStmt(Tok(s.Tok), Tok(s.EndTok), CloneCalcOp(s.Op), lines, s.Hints.ConvertAll(CloneBlockStmt), s.StepOps.ConvertAll(CloneCalcOp), CloneCalcOp(s.ResultOp), CloneAttributes(s.Attributes));
} else if (stmt is MatchStmt) {
var s = (MatchStmt)stmt;
r = new MatchStmt(Tok(s.Tok), Tok(s.EndTok), CloneExpr(s.Source),
s.Cases.ConvertAll(CloneMatchCaseStmt), s.UsesOptionalBraces);
} else if (stmt is AssignSuchThatStmt) {
var s = (AssignSuchThatStmt)stmt;
r = new AssignSuchThatStmt(Tok(s.Tok), Tok(s.EndTok), s.Lhss.ConvertAll(CloneExpr), CloneExpr(s.Expr), s.AssumeToken == null ? null : Tok(s.AssumeToken), null);
} else if (stmt is UpdateStmt) {
var s = (UpdateStmt)stmt;
r = new UpdateStmt(Tok(s.Tok), Tok(s.EndTok), s.Lhss.ConvertAll(CloneExpr), s.Rhss.ConvertAll(CloneRHS), s.CanMutateKnownState);
} else if (stmt is VarDeclStmt) {
var s = (VarDeclStmt)stmt;
var lhss = s.Locals.ConvertAll(c => new LocalVariable(Tok(c.Tok), Tok(c.EndTok), c.Name, CloneType(c.OptionalType), c.IsGhost));
r = new VarDeclStmt(Tok(s.Tok), Tok(s.EndTok), lhss, (ConcreteUpdateStatement)CloneStmt(s.Update));
} else if (stmt is LetStmt) {
var s = (LetStmt)stmt;
r = new LetStmt(Tok(s.Tok), Tok(s.EndTok), s.LHSs.ConvertAll(CloneCasePattern), s.RHSs.ConvertAll(CloneExpr));
} else if (stmt is ModifyStmt) {
var s = (ModifyStmt)stmt;
var mod = CloneSpecFrameExpr(s.Mod);
var body = s.Body == null ? null : CloneBlockStmt(s.Body);
r = new ModifyStmt(Tok(s.Tok), Tok(s.EndTok), mod.Expressions, mod.Attributes, body);
} else if (stmt is TacnyCasesBlockStmt) {
var s = (TacnyCasesBlockStmt)stmt;
var guard = CloneExpr(s.Guard);
var body = s.Body == null ? null : CloneBlockStmt(s.Body);
r = new TacnyCasesBlockStmt(Tok(s.Tok), Tok(s.EndTok), guard, body);
} else if (stmt is TacnyChangedBlockStmt) {
var s = (TacnyChangedBlockStmt)stmt;
var body = s.Body == null ? null : CloneBlockStmt(s.Body);
r = new TacnyChangedBlockStmt(Tok(s.Tok), Tok(s.EndTok), body);
} else if (stmt is TacnySolvedBlockStmt) {
var s = (TacnySolvedBlockStmt)stmt;
var body = s.Body == null ? null : CloneBlockStmt(s.Body);
r = new TacnySolvedBlockStmt(Tok(s.Tok), Tok(s.EndTok), body);
} else if (stmt is TacnyTryCatchBlockStmt) {
var s = (TacnyTryCatchBlockStmt)stmt;
var body = s.Body == null ? null : CloneBlockStmt(s.Body);
var c = s.Ctch == null ? null : CloneBlockStmt(s.Ctch);
r = new TacnyTryCatchBlockStmt(Tok(s.Tok), Tok(s.EndTok), body, c);
} else if (stmt is TacticVarDeclStmt) {
var s = (TacticVarDeclStmt)stmt;
var lhss = s.Locals.ConvertAll(c => new LocalVariable(Tok(c.Tok), Tok(c.EndTok), c.Name, CloneType(c.OptionalType), c.IsGhost));
r = new TacticVarDeclStmt(Tok(s.Tok), Tok(s.EndTok), lhss, (ConcreteUpdateStatement)CloneStmt(s.Update));
} else {
Contract.Assert(false); throw new cce.UnreachableException(); // unexpected statement
}
// add labels to the cloned statement
AddStmtLabels(r, stmt.Labels);
r.Attributes = CloneAttributes(stmt.Attributes);
return r;
}
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);
}
}
private void FindRemovableTypesInForallStmt(ForallStmt forall, Method method, WildCardDecreases wildCardParent, ClassDecl classDecl)
{
FindRemovableTypesInStatement(forall.Body, forall, method, wildCardParent, classDecl);
}