private static WhileStmt GenerateWhileStmt(WhileStmt original, Expression guard, Solution body)
{
var bodyList = body.State.GetAllUpdated();
var thenBody = new BlockStmt(original.Body.Tok, original.Body.EndTok, bodyList);
return(new WhileStmt(original.Tok, original.EndTok, Util.Copy.CopyExpression(guard), original.Invariants, original.Decreases, original.Mod, Util.Copy.CopyBlockStmt(thenBody)));
}
private ForStmt forloop()
{
consume(Token.Type.For);
consume(Token.Type.LeftParenthesis, "Expected '(' for opening for loop specification");
DefStmt counter_definition = define();
consume(Token.Type.IdentifierSeperator, "Expected ',' at expression end");
Expression condition = expression();
consume(Token.Type.IdentifierSeperator, "Expected ',' at expression end");
Expression counter_action = expression();
consume(Token.Type.RightParenthesis, "Expected ')' for closing for loop specification");
// Create the body, along with the counter action
Statement body = new BlockStmt(
new List <Statement>()
{
statement(),
new ExprStmt(counter_action)
});
// Create a while statement
WhileStmt while_stmt = new WhileStmt(condition, body);
return(new ForStmt(counter_definition, while_stmt));
}
private IEnumerable <Solution> GenerateIfStmt(IfStmt original, Expression guard, IEnumerable <Solution> ifStmtEnum, IEnumerable <Solution> elseStmtEnum)
{
foreach (var @if in ifStmtEnum)
{
var bodyList = @if.State.GetAllUpdated();
var ifBody = new BlockStmt(original.Thn.Tok, original.Thn.EndTok, bodyList);
if (elseStmtEnum != null)
{
foreach (var @else in elseStmtEnum)
{
var elseList = @else.State.GetAllUpdated();
Statement elseBody = null;
// if original body was a plain else block
if (original.Els is BlockStmt)
{
elseBody = new BlockStmt(original.Els.Tok, original.Thn.EndTok, elseList);
}
else // otherwise it was a 'else if' and the solution list should only contain one if stmt
{
elseBody = elseList[0];
}
yield return(AddNewStatement(original, new IfStmt(original.Tok, original.EndTok, original.IsExistentialGuard, CopyExpression(guard), CopyBlockStmt(ifBody), elseBody)));
}
}
else
{
yield return(AddNewStatement(original, new IfStmt(original.Tok, original.EndTok, original.IsExistentialGuard, CopyExpression(guard), CopyBlockStmt(ifBody), null)));
}
}
}
public IStatement Function()
{
DataType returnType = Type();
Token name = Consume(TokenType.Identifier, "Expected function name.");
Consume(TokenType.LeftParen, "Expected '(' after function name");
var arguments = new List <Argument>();
while (!Match(TokenType.RightParen))
{
arguments.Add(Argument());
if (Match(TokenType.RightParen))
{
break;
}
Consume(TokenType.Comma, "Expected ',' after argument name.");
}
// Fill DataType array
var dataTypes = new DataType[arguments.Count + 1];
dataTypes[0] = returnType;
for (int i = 0; i < arguments.Count; i++)
{
dataTypes[i + 1] = arguments[i].DataType;
}
Functions[name.Lexeme] = dataTypes;
Consume(TokenType.LeftBrace, "Expected block after function declaration.");
BlockStmt block = (BlockStmt)Block();
return(new FunctionStmt(returnType, name, arguments, block));
}
// Find tactic application and resolve it
private void SearchBlockStmt(BlockStmt body)
{
Contract.Requires(tcce.NonNull(body));
// TODO Make sure this is an OK Thing to be doing
// Currently, if the proof list is not reset, then because it is static across
// calls, it will start to build up old information, and the program will go
// into a loop trying to figure out new fresh names for 'existing' methods.
BaseSearchStrategy.ResetProofList();
_frame.Push(new Dictionary <IVariable, Type>());
foreach (var stmt in body.Body)
{
if (stmt is VarDeclStmt)
{
var vds = stmt as VarDeclStmt;
// register local variable declarations
foreach (var local in vds.Locals)
{
try {
_frame.Peek().Add(local, local.Type);
} catch (Exception e) {
//TODO: some error handling when target is not resolved
Console.Out.WriteLine(e.Message);
}
}
}
else if (stmt is IfStmt)
{
var ifStmt = stmt as IfStmt;
SearchIfStmt(ifStmt);
}
else if (stmt is WhileStmt)
{
var whileStmt = stmt as WhileStmt;
SearchBlockStmt(whileStmt.Body);
}
else if (stmt is UpdateStmt)
{
var us = stmt as UpdateStmt;
if (_state.IsTacticCall(us))
{
var list = StackToDict(_frame);
var result = ApplyTactic(_state, list, us);
if (result != null)
{
_resultList.Add(us.Copy(), result.GetGeneratedCode().Copy());
}
else
{
//TODO what should go here?
}
}
}
else if (stmt is BlockStmt)
{
//TODO:
}
}
_frame.Pop();
}
public ForStmt(string label, Expr value, string variable, BlockStmt body)
{
Label = label;
Value = value;
Variable = variable;
Body = body;
}
private FuncDeclarationStmt MatchFuncDeclaration(string kind)
{
Token name = Consume(TokenType.IDENTIFIER, "Expect " + kind + " name.");
Consume(TokenType.LEFT_PAREN, "Expect '(' after " + kind + " name.");
List <Token> parameters = new List <Token>();
if (Check(TokenType.RIGHT_PAREN) == false)
{
do
{
if (parameters.Count >= 8)
{
ReportError("Cannot have more than 8 parameters.");
}
parameters.Add(Consume(TokenType.IDENTIFIER, "Expect parameter name."));
} while (Match(TokenType.COMMA));
}
Consume(TokenType.RIGHT_PAREN, "Expect ')' after parameters.");
Consume(TokenType.LEFT_BRACE, "Expect '{' before " + kind + " body.");
BlockStmt body = MatchBlockStmt();
return(new FuncDeclarationStmt(name, parameters, body));
}
private void FindRemovableTypesInBlockStmt(BlockStmt blockStmt, Method method, WildCardDecreases wildCardParent, ClassDecl classDecl)
{
foreach (var stmt in blockStmt.Body)
{
FindRemovableTypesInStatement(stmt, blockStmt, method, wildCardParent, classDecl);
}
}
public override void VisitBlockStmt(BlockStmt x)
{
using (new ScopeHelper(this, x))
{
base.VisitBlockStmt(x);
}
}
public string num(List <Statement> selectedStatements, List <AssertStmt> requires, List <AssertStmt> ensures)
{
HashSet <DVariable> decl;
HashSet <DVariable> vars = GetVars(selectedStatements, out decl);
List <Formal> ins = new List <Formal>();
foreach (var variable in vars)
{
ins.Add(variable.ToFormal());
}
// var method = HelpFunctions.GetCurrentMethod();
List <MaybeFreeExpression> req = new List <MaybeFreeExpression>();
foreach (var x in requires)
{
req.Add(new MaybeFreeExpression(x.Expr));
}
List <MaybeFreeExpression> ens = new List <MaybeFreeExpression>();
foreach (var x in ensures)
{
ens.Add(new MaybeFreeExpression(x.Expr));
}
var newMethod = new Method(null, "number", false, false, new List <TypeParameter>(), ins, new List <Formal>(), req, new Specification <FrameExpression>(null, null), ens, new Specification <Microsoft.Dafny.Expression>(null, null), null, null, null);
newMethod.Body = new BlockStmt(selectedStatements.First().Tok, selectedStatements.Last().EndTok, selectedStatements);
string ans = Printer.MethodSignatureToString(newMethod);
Statement statement = new BlockStmt(null, null, selectedStatements);
ans += Printer.StatementToString(statement);
return(ans);
}
public override void Visit(BlockStmt stmt)
{
for (int i = 0; i < stmt.stmts.Count; i++)
{
stmt.stmts[i].Accept(this);
}
}
public virtual void Visit(BlockStmt stmt)
{
foreach (var statement in stmt.Statements)
{
statement.Accept(this);
}
}
public override void VisitBlockStmt(BlockStmt x)
{
Add(_binder.BindEmptyStmt(new Span(x.Span.Start, 1))); // {
base.VisitBlockStmt(x); // visit nested statements
Add(_binder.BindEmptyStmt(new Span(x.Span.End - 1, 1))); // } // TODO: endif; etc.
}
protected override void MatchBlockStmt(BlockStmt stmt)
{
BeginScope();
Resolve(stmt.Statements);
EndScope();
}
public virtual void Visit(BlockStmt blockStatement)
{
VisitNullableAttributes(blockStatement.Attributes);
foreach (var statement in blockStatement.Body)
{
Visit(statement);
}
}
public virtual BlockStmt CloneBlockStmt(BlockStmt stmt)
{
if (stmt == null) {
return null;
} else {
return new BlockStmt(Tok(stmt.Tok), Tok(stmt.EndTok), stmt.Body.ConvertAll(CloneStmt));
}
}
internal Statement GetTacticAppStmt(int pos, BlockStmt stmts)
{
if (stmts.Body == null)
{
return(null);
}
return(GetTacticAppStmt(pos, stmts.Body));
}
public string Transpile(CompilerContext context)
{
var code = new StringBuilder();
code.AppendLine($"while({Condition.Transpile(context)}) {{ ");
code.AppendLine(BlockStmt.Transpile(context));
code.AppendLine("}");
return(code.ToString());
}
public override void Visit(BlockStmt blockStatement)
{
var oldBlock = _block;
_block = new ScopeSymbol(_block, blockStatement);
oldBlock.Symbols.Add(_block);
base.Visit(blockStatement);
_block = oldBlock;
}
/// <summary>
/// LoopStmt
/// WHILE LPAREN Expr RPAREN (SELICOLON | BlockStmt)
/// FOR LPAREN (VarOrExprStmt | SEMICOLON) Expr? SEMICOLON ExprList? RPAREN (SELICOLON | BlockStmt)
/// </summary>
/// <returns></returns>
private LoopStmt ParseLoopStmt()
{
BlockStmt body = null;
Expr cond = null;
if (Check(TokenType.WHILE))
{
Consume(TokenType.WHILE);
Consume(TokenType.LPAREN);
cond = ParseExpr();
Consume(TokenType.RPAREN);
if (Check(TokenType.SEMICOLON))
{
Consume(TokenType.SEMICOLON);
}
else
{
body = ParseBlockStmt();
}
return(LoopStmt.MakeWhile(cond, body));
}
else
{
Consume(TokenType.FOR);
Consume(TokenType.LPAREN);
Stmt init = null;
Expr step = null;
if (!Check(TokenType.SEMICOLON))
{
init = ParseVarOrExprStmt();
}
else
{
Consume(TokenType.SEMICOLON);
}
if (!Check(TokenType.SEMICOLON))
{
cond = ParseExpr();
}
Consume(TokenType.SEMICOLON);
if (!Check(TokenType.RPAREN))
{
step = ParseExprList();
}
Consume(TokenType.RPAREN);
if (Check(TokenType.SEMICOLON))
{
Consume(TokenType.SEMICOLON);
}
else
{
body = ParseBlockStmt();
}
return(LoopStmt.MakeFor(init, cond, step, body));
}
}
// Find tactic application and resolve it
private void SearchBlockStmt(BlockStmt body)
{
Contract.Requires(tcce.NonNull(body));
// BaseSearchStrategy.ResetProofList();
_frame.Push(new Dictionary <IVariable, Type>());
foreach (var stmt in body.Body)
{
if (stmt is VarDeclStmt)
{
var vds = stmt as VarDeclStmt;
// register local variable declarations
foreach (var local in vds.Locals)
{
try {
_frame.Peek().Add(local, local.Type);
} catch (Exception e) {
//TODO: some error handling when target is not resolved
Console.Out.WriteLine(e.Message);
}
}
}
else if (stmt is IfStmt)
{
var ifStmt = stmt as IfStmt;
SearchIfStmt(ifStmt);
}
else if (stmt is WhileStmt)
{
var whileStmt = stmt as WhileStmt;
SearchBlockStmt(whileStmt.Body);
}
else if (stmt is UpdateStmt)
{
var us = stmt as UpdateStmt;
if (_state.IsTacticCall(us))
{
var list = StackToDict(_frame);
var result = EvalTactic(_state, list, us);
if (result != null)
{
_resultList.Add(us.Copy(), result.GetGeneratedCode().Copy());
}
else// when no results, just return a empty stmt list
{
_resultList.Add(us.Copy(), new List <Statement>());
}
}
}
else if (stmt is BlockStmt)
{
//TODO:
}
}
_frame.Pop();
}
public static void PrepareFrame(BlockStmt body, ProofState state)
{
Contract.Requires <ArgumentNullException>(body != null, "body");
Contract.Requires <ArgumentNullException>(state != null, "state");
state.AddNewFrame(body);
// call the search engine
var search = new BaseSearchStrategy(state.TacticInfo.SearchStrategy, true);
search.Search(state, _errorReporterDelegate);
state.RemoveFrame();
}
public object Visit(BlockStmt stmt)
{
_scope = _scope.AddChildScope();
foreach (var statement in stmt.Statements)
{
statement.Accept(this);
}
_scope = _scope.Parent;
return(null);
}
public void TestReturnInFunctionWithoutValue()
{
var program = new ProgramNode(0, 0);
program.Block = new BlockStmt(0, 0);
var returnStmt = new ReturnStmt(0, 0);
var funcBlock = new BlockStmt(0, 0);
funcBlock.Statements.Add(returnStmt);
program.Block.Statements.Add(CreateFunction("func", funcBlock));
AssertErrorContains(program, "Return statement can't be empty in a function");
}
public Value CompileBlockStmt(BlockStmt stmt)
{
switch (stmt)
{
case BlockLet s: return(CompileBlockStmt(s));
case BlockExpr e: return(CompileExpr(e.Expr));
default:
throw new Exception("unknown AST node " + stmt.GetType());
}
}
private BlockStmt MatchBlockStmt()
{
List <Stmt> stmts = new List <Stmt>();
while (Check(TokenType.RIGHT_BRACE) == false && IsAtEnd() == false)
{
stmts.Add(MatchDeclaration());
}
Consume(TokenType.RIGHT_BRACE, "Expect '}' after block.");
BlockStmt block = new BlockStmt(stmts);
return(block);
}
public void TestCorrectReturnInFuction()
{
var program = new ProgramNode(0, 0);
program.Block = new BlockStmt(0, 0);
var funcBlock = new BlockStmt(0, 0);
var returnStmt = new ReturnStmt(0, 0);
returnStmt.ReturnExpression = new IntLiteralExpr(0, 0, 0);
funcBlock.Statements.Add(returnStmt);
program.Block.Statements.Add(CreateFunction("func", funcBlock));
AssertNoErrors(program);
}
public Emit <Func <int> > EmitByteCode(CompilerContext context, Emit <Func <int> > emiter)
{
var loopLabel = emiter.DefineLabel();
var outLabel = emiter.DefineLabel();
emiter.MarkLabel(loopLabel);
Condition.EmitByteCode(context, emiter);
emiter.BranchIfFalse(outLabel);
BlockStmt.EmitByteCode(context, emiter);
emiter.Branch(loopLabel);
emiter.MarkLabel(outLabel);
return(emiter);
}
public Statement ParseFunctionCallStatement()
{
string function = ConsumeToken(TokenKind.Identifier).Source;
ConsumeToken(TokenKind.OpenParen);
var arguments = ParseArgumentList();
ConsumeToken(TokenKind.CloseParen);
var call = new FunctionCallStmt {
MethodName = function,
Arguments = arguments.ToArray()
};
switch (CurrentToken.Kind)
{
case TokenKind.Semicolon:
ConsumeToken();
break;
case TokenKind.OpenBrace:
if (function.Equals("if", StringComparison.CurrentCultureIgnoreCase))
{
var body = ParseBlockStatement();
BlockStmt elseBody = null;
if (CurrentToken.Kind == TokenKind.Identifier && CurrentToken.Source.Equals("else", StringComparison.CurrentCultureIgnoreCase))
{
ConsumeToken();
elseBody = ParseBlockStatement();
}
return(new IfStmt {
Function = call,
Body = body,
ElseBody = elseBody
});
}
return(new BodyFunctionStmt {
Function = call,
Body = ParseBlockStatement()
});
default:
throw new UnexpectedTokenException(CurrentToken, TokenKind.Semicolon, TokenKind.OpenBrace);
}
return(call);
}
public void TestRedeclarationInInnerScope()
{
var program = new ProgramNode(0, 0);
program.Block = new BlockStmt(0, 0);
var declaration1 = CreateVarDeclaration("var1");
var declaration2 = CreateVarDeclaration("var2");
var innerBlock = new BlockStmt(0, 0);
innerBlock.Statements.Add(declaration2);
program.Block.Statements.Add(declaration1);
program.Block.Statements.Add(innerBlock);
AssertNoErrors(program);
}
public void TestReturnOfWrongType()
{
var program = new ProgramNode(0, 0);
program.Block = new BlockStmt(0, 0);
var returnStmt = new ReturnStmt(0, 0);
returnStmt.ReturnExpression = new StringLiteralExpr(0, 0, "asd");
var funcBlock = new BlockStmt(0, 0);
funcBlock.Statements.Add(returnStmt);
program.Block.Statements.Add(CreateFunction("func", funcBlock));
AssertErrorContains(program, "Can't return a value of type String in a function of type Int");
}
public static IEnumerable<Solution> SearchBlockStmt(BlockStmt body, Atomic atomic) {
Atomic ac = atomic.Copy();
ac.DynamicContext.tacticBody = body.Body;
ac.DynamicContext.ResetCounter();
List<Solution> result = new List<Solution> { new Solution(ac) };
// search strategy for body goes here
while (true) {
List<Solution> interm = new List<Solution>();
if (result.Count == 0)
break;
foreach (var solution in result) {
foreach (var item in Atomic.ResolveStatement(solution)) {
if (item.State.DynamicContext.isPartialyResolved) {
{ interm.Add(item); }
yield return item;
} else if (item.State.DynamicContext.GetCurrentStatement() == null) { yield return item; } else { interm.Add(item); }
}
}
result.Clear();
result.AddRange(interm);
}
}
/// <summary>
/// Create deep copy of BlockStmt
/// </summary>
/// <param name="stmt"></param>
/// <returns></returns>
public static BlockStmt CopyBlockStmt(BlockStmt stmt) {
return new BlockStmt(stmt.Tok, stmt.EndTok, CopyStatementList(stmt.Body));
}
void CalcStmt(out Statement s)
{
Contract.Ensures(Contract.ValueAtReturn(out s) != null);
Token x;
Attributes attrs = null;
CalcStmt.CalcOp op, calcOp = Microsoft.Dafny.CalcStmt.DefaultOp, resOp = Microsoft.Dafny.CalcStmt.DefaultOp;
var lines = new List<Expression>();
var hints = new List<BlockStmt>();
CalcStmt.CalcOp stepOp;
var stepOps = new List<CalcStmt.CalcOp>();
CalcStmt.CalcOp maybeOp;
Expression e;
IToken opTok;
IToken danglingOperator = null;
Expect(32);
x = t;
while (IsAttribute()) {
Attribute(ref attrs);
}
if (StartOf(25)) {
CalcOp(out opTok, out calcOp);
maybeOp = calcOp.ResultOp(calcOp); // guard against non-transitive calcOp (like !=)
if (maybeOp == null) {
SemErr(opTok, "the main operator of a calculation must be transitive");
}
resOp = calcOp;
}
Expect(46);
while (StartOf(7)) {
Expression(out e, false, true);
lines.Add(e); stepOp = calcOp; danglingOperator = null;
Expect(28);
if (StartOf(25)) {
CalcOp(out opTok, out op);
maybeOp = resOp.ResultOp(op);
if (maybeOp == null) {
SemErr(opTok, "this operator cannot continue this calculation");
} else {
stepOp = op;
resOp = maybeOp;
danglingOperator = opTok;
}
}
stepOps.Add(stepOp);
var subhints = new List<Statement>();
IToken hintStart = la; IToken hintEnd = hintStart;
IToken t0, t1;
BlockStmt subBlock; Statement subCalc;
while (la.kind == _lbrace || la.kind == _calc) {
if (la.kind == 46) {
BlockStmt(out subBlock, out t0, out t1);
hintEnd = subBlock.EndTok; subhints.Add(subBlock);
} else if (la.kind == 32) {
CalcStmt(out subCalc);
hintEnd = subCalc.EndTok; subhints.Add(subCalc);
} else SynErr(192);
}
var h = new BlockStmt(hintStart, hintEnd, subhints); // if the hint is empty, hintStart is the first token of the next line, but it doesn't matter because the block statement is just used as a container
hints.Add(h);
if (h.Body.Count != 0) { danglingOperator = null; }
}
Expect(47);
if (danglingOperator != null) {
SemErr(danglingOperator, "a calculation cannot end with an operator");
}
if (lines.Count > 0) {
// Repeat the last line to create a dummy line for the dangling hint
lines.Add(lines[lines.Count - 1]);
}
s = new CalcStmt(x, t, calcOp, lines, hints, stepOps, resOp, attrs);
}
public static void PrepareFrame(BlockStmt body, ProofState state) {
Contract.Requires<ArgumentNullException>(body != null, "body");
Contract.Requires<ArgumentNullException>(state != null, "state");
state.AddNewFrame(body);
// call the search engine
var search = new BaseSearchStrategy(state.TacticInfo.SearchStrategy, true);
search.Search(state, _errorReporterDelegate);
state.RemoveFrame();
}
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 void AddNewFrame(BlockStmt body) {
Contract.Requires<ArgumentNullException>(body != null, "body");
//Contract.Requires<ArgumentNullException>(_scope.Count > 0, "scope");
_scope.Push(new Frame(_scope.Peek(), body.Body));
}
// Find tactic application and resolve it
private void SearchBlockStmt(BlockStmt body) {
Contract.Requires(tcce.NonNull(body));
// BaseSearchStrategy.ResetProofList();
_frame.Push(new Dictionary<IVariable, Type>());
foreach(var stmt in body.Body) {
if(stmt is VarDeclStmt) {
var vds = stmt as VarDeclStmt;
// register local variable declarations
foreach(var local in vds.Locals) {
try {
_frame.Peek().Add(local, local.Type);
} catch(Exception e) {
//TODO: some error handling when target is not resolved
Console.Out.WriteLine(e.Message);
}
}
} else if(stmt is IfStmt) {
var ifStmt = stmt as IfStmt;
SearchIfStmt(ifStmt);
} else if(stmt is WhileStmt) {
var whileStmt = stmt as WhileStmt;
SearchBlockStmt(whileStmt.Body);
} else if(stmt is UpdateStmt) {
var us = stmt as UpdateStmt;
if(_state.IsTacticCall(us)) {
var list = StackToDict(_frame);
var result = EvalTactic(_state, list, us);
if(result != null)
_resultList.Add(us.Copy(), result.GetGeneratedCode().Copy());
else {// when no results, just return a empty stmt list
_resultList.Add(us.Copy(), new List<Statement>());
}
}
} else if(stmt is BlockStmt) {
//TODO:
}
}
_frame.Pop();
}
private void FindRemovableTypesInBlockStmt(BlockStmt blockStmt, Method method, WildCardDecreases wildCardParent, ClassDecl classDecl)
{
foreach (var stmt in blockStmt.Body)
FindRemovableTypesInStatement(stmt, blockStmt, method, wildCardParent, classDecl);
}
BlockStmt MergeBlockStmt(BlockStmt skeleton, BlockStmt oldStmt)
{
Contract.Requires(skeleton != null);
Contract.Requires(oldStmt != null);
var body = new List<Statement>();
int i = 0, j = 0;
while (i < skeleton.Body.Count) {
var cur = skeleton.Body[i];
if (j == oldStmt.Body.Count) {
if (!(cur is SkeletonStatement)) {
MergeAddStatement(cur, body);
} else if (((SkeletonStatement)cur).S == null) {
// the "..." matches the empty statement sequence
} else {
reporter.Error(MessageSource.RefinementTransformer, cur.Tok, "skeleton statement does not match old statement");
}
i++;
} else {
var oldS = oldStmt.Body[j];
/* See how the two statements match up.
* oldS cur result
* ------ ------ ------
* assume E; assert ...; assert E;
* assert E; assert ...; assert E;
* assert E; assert E;
*
* assume E; assume ...; assume E;
*
* var x; var x := E; var x := E;
* var x := *; var x := E; var x := E;
* var x :| P; var x := E1; var x := E1; assert P;
* var VarProduction; var VarProduction;
*
* x := *; x := E; x := E;
* x :| P; x := E; x := E; assert P;
*
* modify E; modify ...; modify E;
* modify E; modify ... { S } modify E { S }
* modify E { S } modify ... { S' } modify E { Merge(S, S') }
*
* if (G) Then' else Else' if ... Then else Else if (G) Merge(Then,Then') else Merge(Else,Else')
* if (*) Then' else Else' if (G) Then else Else if (G) Merge(Then,Then') else Merge(Else,Else')
*
* while (G) LoopSpec' Body while ... LoopSpec ... while (G) Merge(LoopSpec,LoopSpec') Body
* while (G) LoopSpec' Body' while ... LoopSpec Body while (G) Merge(LoopSpec,LoopSpec') Merge(Body,Body')
* while (*) LoopSpec' Body while (G) LoopSpec ... while (G) Merge(LoopSpec,LoopSpec') Body
* while (*) LoopSpec' Body' while (G) LoopSpec Body while (G) Merge(LoopSpec,LoopSpec') Merge(Body,Body')
*
* StmtThatDoesNotMatchS; S' ... where x = e; S StatementThatDoesNotMatchS[e/x]; Merge( ... where x = e; S , S')
* StmtThatMatchesS; S' ... where x = e; S StmtThatMatchesS; S'
*
* Note, LoopSpec must contain only invariant declarations (as the parser ensures for the first three cases).
* Note, there is an implicit "...;" at the end of every block in a skeleton.
*/
if (cur is SkeletonStatement) {
var c = (SkeletonStatement)cur;
var S = c.S;
if (S == null) {
var nxt = i + 1 == skeleton.Body.Count ? null : skeleton.Body[i + 1];
if (nxt != null && nxt is SkeletonStatement && ((SkeletonStatement)nxt).S == null) {
// "...; ...;" is the same as just "...;", so skip this one
} else {
SubstitutionCloner subber = null;
if (c.NameReplacements != null) {
var subExprs = new Dictionary<string, Expression>();
Contract.Assert(c.NameReplacements.Count == c.ExprReplacements.Count);
for (int k = 0; k < c.NameReplacements.Count; k++) {
if (subExprs.ContainsKey(c.NameReplacements[k].val)) {
reporter.Error(MessageSource.RefinementTransformer, c.NameReplacements[k], "replacement definition must contain at most one definition for a given label");
} else subExprs.Add(c.NameReplacements[k].val, c.ExprReplacements[k]);
}
subber = new SubstitutionCloner(subExprs, rawCloner);
}
// skip up until the next thing that matches "nxt"
var hoverTextA = "";
var sepA = "";
while (nxt == null || !PotentialMatch(nxt, oldS)) {
// loop invariant: oldS == oldStmt.Body[j]
var s = refinementCloner.CloneStmt(oldS);
if (subber != null)
s = subber.CloneStmt(s);
body.Add(s);
hoverTextA += sepA + Printer.StatementToString(s);
sepA = "\n";
j++;
if (j == oldStmt.Body.Count) { break; }
oldS = oldStmt.Body[j];
}
if (hoverTextA.Length != 0) {
reporter.Info(MessageSource.RefinementTransformer, c.Tok, hoverTextA);
}
if (subber != null && subber.SubstitutionsMade.Count < subber.Exprs.Count) {
foreach (var s in subber.SubstitutionsMade)
subber.Exprs.Remove(s);
reporter.Error(MessageSource.RefinementTransformer, c.Tok, "could not find labeled expression(s): " + Util.Comma(", ", subber.Exprs.Keys, x => x));
}
}
i++;
} else if (S is AssertStmt) {
var skel = (AssertStmt)S;
Contract.Assert(c.ConditionOmitted);
var oldAssume = oldS as PredicateStmt;
if (oldAssume == null) {
reporter.Error(MessageSource.RefinementTransformer, cur.Tok, "assert template does not match inherited statement");
i++;
} else {
// Clone the expression, but among the new assert's attributes, indicate
// that this assertion is supposed to be translated into a check. That is,
// it is not allowed to be just assumed in the translation, despite the fact
// that the condition is inherited.
var e = refinementCloner.CloneExpr(oldAssume.Expr);
var attrs = refinementCloner.MergeAttributes(oldAssume.Attributes, skel.Attributes);
body.Add(new AssertStmt(new Translator.ForceCheckToken(skel.Tok), new Translator.ForceCheckToken(skel.EndTok),
e, skel.Proof, new Attributes("prependAssertToken", new List<Expression>(), attrs)));
reporter.Info(MessageSource.RefinementTransformer, c.ConditionEllipsis, "assume->assert: " + Printer.ExprToString(e));
i++; j++;
}
} else if (S is AssumeStmt) {
var skel = (AssumeStmt)S;
Contract.Assert(c.ConditionOmitted);
var oldAssume = oldS as AssumeStmt;
if (oldAssume == null) {
reporter.Error(MessageSource.RefinementTransformer, cur.Tok, "assume template does not match inherited statement");
i++;
} else {
var e = refinementCloner.CloneExpr(oldAssume.Expr);
var attrs = refinementCloner.MergeAttributes(oldAssume.Attributes, skel.Attributes);
body.Add(new AssumeStmt(skel.Tok, skel.EndTok, e, attrs));
reporter.Info(MessageSource.RefinementTransformer, c.ConditionEllipsis, Printer.ExprToString(e));
i++; j++;
}
} else if (S is IfStmt) {
var skel = (IfStmt)S;
Contract.Assert(c.ConditionOmitted);
var oldIf = oldS as IfStmt;
if (oldIf == null) {
reporter.Error(MessageSource.RefinementTransformer, cur.Tok, "if-statement template does not match inherited statement");
i++;
} else {
var resultingThen = MergeBlockStmt(skel.Thn, oldIf.Thn);
var resultingElse = MergeElse(skel.Els, oldIf.Els);
var e = refinementCloner.CloneExpr(oldIf.Guard);
var r = new IfStmt(skel.Tok, skel.EndTok, oldIf.IsExistentialGuard, e, resultingThen, resultingElse);
body.Add(r);
reporter.Info(MessageSource.RefinementTransformer, c.ConditionEllipsis, Printer.GuardToString(oldIf.IsExistentialGuard, e));
i++; j++;
}
} else if (S is WhileStmt) {
var skel = (WhileStmt)S;
var oldWhile = oldS as WhileStmt;
if (oldWhile == null) {
reporter.Error(MessageSource.RefinementTransformer, cur.Tok, "while-statement template does not match inherited statement");
i++;
} else {
Expression guard;
if (c.ConditionOmitted) {
guard = refinementCloner.CloneExpr(oldWhile.Guard);
reporter.Info(MessageSource.RefinementTransformer, c.ConditionEllipsis, Printer.GuardToString(false, oldWhile.Guard));
} else {
if (oldWhile.Guard != null) {
reporter.Error(MessageSource.RefinementTransformer, skel.Guard.tok, "a skeleton while statement with a guard can only replace a while statement with a non-deterministic guard");
}
guard = skel.Guard;
}
// Note, if the loop body is omitted in the skeleton, the parser will have set the loop body to an empty block,
// which has the same merging behavior.
var r = MergeWhileStmt(skel, oldWhile, guard);
body.Add(r);
i++; j++;
}
} else if (S is ModifyStmt) {
var skel = (ModifyStmt)S;
Contract.Assert(c.ConditionOmitted);
var oldModifyStmt = oldS as ModifyStmt;
if (oldModifyStmt == null) {
reporter.Error(MessageSource.RefinementTransformer, cur.Tok, "modify template does not match inherited statement");
i++;
} else {
var mod = refinementCloner.CloneSpecFrameExpr(oldModifyStmt.Mod);
BlockStmt mbody;
if (oldModifyStmt.Body == null && skel.Body == null) {
mbody = null;
} else if (oldModifyStmt.Body == null) {
mbody = skel.Body;
} else if (skel.Body == null) {
reporter.Error(MessageSource.RefinementTransformer, cur.Tok, "modify template must have a body if the inherited modify statement does");
mbody = null;
} else {
mbody = MergeBlockStmt(skel.Body, oldModifyStmt.Body);
}
body.Add(new ModifyStmt(skel.Tok, skel.EndTok, mod.Expressions, mod.Attributes, mbody));
reporter.Info(MessageSource.RefinementTransformer, c.ConditionEllipsis, Printer.FrameExprListToString(mod.Expressions));
i++; j++;
}
} else {
Contract.Assume(false); // unexpected skeleton statement
}
} else if (cur is AssertStmt) {
MergeAddStatement(cur, body);
i++;
} else if (cur is VarDeclStmt) {
var cNew = (VarDeclStmt)cur;
bool doMerge = false;
Expression addedAssert = null;
if (oldS is VarDeclStmt) {
var cOld = (VarDeclStmt)oldS;
if (LocalVarsAgree(cOld.Locals, cNew.Locals)) {
var update = cNew.Update as UpdateStmt;
if (update != null && update.Rhss.TrueForAll(rhs => !rhs.CanAffectPreviouslyKnownExpressions)) {
// Note, we allow switching between ghost and non-ghost, since that seems unproblematic.
if (cOld.Update == null) {
doMerge = true;
} else if (cOld.Update is AssignSuchThatStmt) {
doMerge = true;
addedAssert = refinementCloner.CloneExpr(((AssignSuchThatStmt)cOld.Update).Expr);
} else {
var updateOld = (UpdateStmt)cOld.Update; // if cast fails, there are more ConcreteUpdateStatement subclasses than expected
doMerge = true;
foreach (var rhs in updateOld.Rhss) {
if (!(rhs is HavocRhs))
doMerge = false;
}
}
}
}
}
if (doMerge) {
// Go ahead with the merge:
body.Add(cNew);
i++; j++;
if (addedAssert != null) {
var tok = new Translator.ForceCheckToken(addedAssert.tok);
body.Add(new AssertStmt(tok, tok, addedAssert, null, null));
}
} else {
MergeAddStatement(cur, body);
i++;
}
} else if (cur is AssignStmt) {
var cNew = (AssignStmt)cur;
var cOld = oldS as AssignStmt;
if (cOld == null && oldS is UpdateStmt) {
var us = (UpdateStmt)oldS;
if (us.ResolvedStatements.Count == 1) {
cOld = us.ResolvedStatements[0] as AssignStmt;
}
}
bool doMerge = false;
if (cOld != null && cNew.Lhs.WasResolved() && cOld.Lhs.WasResolved()) {
var newLhs = cNew.Lhs.Resolved as IdentifierExpr;
var oldLhs = cOld.Lhs.Resolved as IdentifierExpr;
if (newLhs != null && oldLhs != null && newLhs.Name == oldLhs.Name) {
if (!(cNew.Rhs is TypeRhs) && cOld.Rhs is HavocRhs) {
doMerge = true;
}
}
}
if (doMerge) {
// Go ahead with the merge:
body.Add(cNew);
i++; j++;
} else {
MergeAddStatement(cur, body);
i++;
}
} else if (cur is UpdateStmt) {
var nw = (UpdateStmt)cur;
List<Statement> stmtGenerated = new List<Statement>();
bool doMerge = false;
if (oldS is UpdateStmt) {
var s = (UpdateStmt)oldS;
if (LeftHandSidesAgree(s.Lhss, nw.Lhss)) {
doMerge = true;
stmtGenerated.Add(nw);
foreach (var rhs in s.Rhss) {
if (!(rhs is HavocRhs))
doMerge = false;
}
}
} else if (oldS is AssignSuchThatStmt) {
var s = (AssignSuchThatStmt)oldS;
if (LeftHandSidesAgree(s.Lhss, nw.Lhss)) {
doMerge = true;
stmtGenerated.Add(nw);
var addedAssert = refinementCloner.CloneExpr(s.Expr);
var tok = new Translator.ForceCheckToken(addedAssert.tok);
stmtGenerated.Add(new AssertStmt(tok, tok, addedAssert, null, null));
}
}
if (doMerge) {
// Go ahead with the merge:
Contract.Assert(cce.NonNullElements(stmtGenerated));
body.AddRange(stmtGenerated);
i++; j++;
} else {
MergeAddStatement(cur, body);
i++;
}
} else if (cur is IfStmt) {
var cNew = (IfStmt)cur;
var cOld = oldS as IfStmt;
if (cOld != null && cOld.Guard == null) {
var r = new IfStmt(cNew.Tok, cNew.EndTok, cNew.IsExistentialGuard, cNew.Guard, MergeBlockStmt(cNew.Thn, cOld.Thn), MergeElse(cNew.Els, cOld.Els));
body.Add(r);
i++; j++;
} else {
MergeAddStatement(cur, body);
i++;
}
} else if (cur is WhileStmt) {
var cNew = (WhileStmt)cur;
var cOld = oldS as WhileStmt;
if (cOld != null && cOld.Guard == null) {
var r = MergeWhileStmt(cNew, cOld, cNew.Guard);
body.Add(r);
i++; j++;
} else {
MergeAddStatement(cur, body);
i++;
}
} else if (cur is BlockStmt) {
var cNew = (BlockStmt)cur;
var cOld = oldS as BlockStmt;
if (cOld != null) {
var r = MergeBlockStmt(cNew, cOld);
body.Add(r);
i++; j++;
} else {
MergeAddStatement(cur, body);
i++;
}
} else {
MergeAddStatement(cur, body);
i++;
}
}
}
// implement the implicit "...;" at the end of each block statement skeleton
var hoverText = "";
var sep = "";
for (; j < oldStmt.Body.Count; j++) {
var b = oldStmt.Body[j];
body.Add(refinementCloner.CloneStmt(b));
hoverText += sep + Printer.StatementToString(b);
sep = "\n";
}
if (hoverText.Length != 0) {
reporter.Info(MessageSource.RefinementTransformer, skeleton.EndTok, hoverText);
}
return new BlockStmt(skeleton.Tok, skeleton.EndTok, body);
}
Method CloneMethod(Method m, List<MaybeFreeExpression> moreEnsures, Specification<Expression> decreases, BlockStmt newBody, bool checkPreviousPostconditions, Attributes moreAttributes)
{
Contract.Requires(m != null);
Contract.Requires(decreases != null);
var tps = m.TypeArgs.ConvertAll(refinementCloner.CloneTypeParam);
var ins = m.Ins.ConvertAll(refinementCloner.CloneFormal);
var req = m.Req.ConvertAll(refinementCloner.CloneMayBeFreeExpr);
var mod = refinementCloner.CloneSpecFrameExpr(m.Mod);
List<MaybeFreeExpression> ens;
if (checkPreviousPostconditions)
ens = m.Ens.ConvertAll(rawCloner.CloneMayBeFreeExpr);
else
ens = m.Ens.ConvertAll(refinementCloner.CloneMayBeFreeExpr);
if (moreEnsures != null) {
ens.AddRange(moreEnsures);
}
var body = newBody ?? refinementCloner.CloneBlockStmt(m.BodyForRefinement);
if (m is Constructor) {
return new Constructor(new RefinementToken(m.tok, moduleUnderConstruction), m.Name, tps, ins,
req, mod, ens, decreases, body, refinementCloner.MergeAttributes(m.Attributes, moreAttributes), null, m);
} else if (m is InductiveLemma) {
return new InductiveLemma(new RefinementToken(m.tok, moduleUnderConstruction), m.Name, m.HasStaticKeyword, tps, ins, m.Outs.ConvertAll(refinementCloner.CloneFormal),
req, mod, ens, decreases, body, refinementCloner.MergeAttributes(m.Attributes, moreAttributes), null, m);
} else if (m is CoLemma) {
return new CoLemma(new RefinementToken(m.tok, moduleUnderConstruction), m.Name, m.HasStaticKeyword, tps, ins, m.Outs.ConvertAll(refinementCloner.CloneFormal),
req, mod, ens, decreases, body, refinementCloner.MergeAttributes(m.Attributes, moreAttributes), null, m);
} else if (m is Lemma) {
return new Lemma(new RefinementToken(m.tok, moduleUnderConstruction), m.Name, m.HasStaticKeyword, tps, ins, m.Outs.ConvertAll(refinementCloner.CloneFormal),
req, mod, ens, decreases, body, refinementCloner.MergeAttributes(m.Attributes, moreAttributes), null, m);
} else if (m is TwoStateLemma) {
var two = (TwoStateLemma)m;
return new TwoStateLemma(new RefinementToken(m.tok, moduleUnderConstruction), m.Name, m.HasStaticKeyword, tps, ins, m.Outs.ConvertAll(refinementCloner.CloneFormal),
req, mod, ens, decreases, body, refinementCloner.MergeAttributes(m.Attributes, moreAttributes), null, m);
} else {
return new Method(new RefinementToken(m.tok, moduleUnderConstruction), m.Name, m.HasStaticKeyword, m.IsGhost, tps, ins, m.Outs.ConvertAll(refinementCloner.CloneFormal),
req, mod, ens, decreases, body, refinementCloner.MergeAttributes(m.Attributes, moreAttributes), null, m);
}
}
Statement MergeElse(Statement skeleton, Statement oldStmt)
{
Contract.Requires(skeleton == null || skeleton is BlockStmt || skeleton is IfStmt || skeleton is SkeletonStatement);
Contract.Requires(oldStmt == null || oldStmt is BlockStmt || oldStmt is IfStmt || oldStmt is SkeletonStatement);
if (skeleton == null) {
return refinementCloner.CloneStmt(oldStmt);
} else if (skeleton is IfStmt || skeleton is SkeletonStatement) {
// wrap a block statement around the if statement
skeleton = new BlockStmt(skeleton.Tok, skeleton.EndTok, new List<Statement>() { skeleton });
}
if (oldStmt == null) {
// make it into an empty block statement
oldStmt = new BlockStmt(skeleton.Tok, skeleton.EndTok, new List<Statement>());
} else if (oldStmt is IfStmt || oldStmt is SkeletonStatement) {
// wrap a block statement around the if statement
oldStmt = new BlockStmt(oldStmt.Tok, skeleton.EndTok, new List<Statement>() { oldStmt });
}
Contract.Assert(skeleton is BlockStmt && oldStmt is BlockStmt);
return MergeBlockStmt((BlockStmt)skeleton, (BlockStmt)oldStmt);
}
private static Method GenerateMethod(Method oldMd, List<Statement> body, Method source = null) {
var src = source ?? oldMd;
var mdBody = new BlockStmt(src.Body.Tok, src.Body.EndTok, body);
var type = src.GetType();
if (type == typeof(Lemma))
return new Lemma(src.tok, src.Name, src.HasStaticKeyword, src.TypeArgs, src.Ins, src.Outs, src.Req, src.Mod,
src.Ens, src.Decreases, mdBody, src.Attributes, src.SignatureEllipsis);
if (type == typeof(CoLemma))
return new CoLemma(src.tok, src.Name, src.HasStaticKeyword, src.TypeArgs, src.Ins, src.Outs, src.Req, src.Mod,
src.Ens, src.Decreases, mdBody, src.Attributes, src.SignatureEllipsis);
return new Method(src.tok, src.Name, src.HasStaticKeyword, src.IsGhost,
src.TypeArgs, src.Ins, src.Outs, src.Req, src.Mod, src.Ens, src.Decreases,
mdBody, src.Attributes, src.SignatureEllipsis);
}
private static WhileStmt GenerateWhileStmt(WhileStmt original, Expression guard, Solution body) {
var bodyList = body.State.GetAllUpdated();
var thenBody = new BlockStmt(original.Body.Tok, original.Body.EndTok, bodyList);
return new WhileStmt(original.Tok, original.EndTok, Util.Copy.CopyExpression(guard), original.Invariants, original.Decreases, original.Mod, Util.Copy.CopyBlockStmt(thenBody));
}
public static IEnumerable<Solution> SearchBlockStmt(BlockStmt body, Atomic atomic) {
Atomic ac = atomic.Copy();
ac.DynamicContext.tacticBody = body.Body;
ac.DynamicContext.ResetCounter();
Stack<IEnumerator<Solution>> solutionStack = new Stack<IEnumerator<Solution>>();
solutionStack.Push(Atomic.ResolveStatement(new Solution(ac)).GetEnumerator());
while (true) {
if (solutionStack.Count == 0) {
yield break;
}
var solutionEnum = solutionStack.Pop();
// if the solution is fully resolved skip resolution
if (!solutionEnum.MoveNext())
continue;
var solution = solutionEnum.Current;
solutionStack.Push(solutionEnum);
if (solution.State.DynamicContext.isPartialyResolved) {
solutionStack.Push(Atomic.ResolveStatement(solution).GetEnumerator());
yield return solution;
} else if (solution.State.DynamicContext.GetCurrentStatement() == null) {
yield return solution;
} else { solutionStack.Push(Atomic.ResolveStatement(solution).GetEnumerator()); }
}
}
void UpdateStmt(out Statement/*!*/ s)
{
List<Expression> lhss = new List<Expression>();
List<AssignmentRhs> rhss = new List<AssignmentRhs>();
Expression e; AssignmentRhs r;
IToken x, endTok = Token.NoToken;
Attributes attrs = null;
IToken suchThatAssume = null;
Expression suchThat = null;
Lhs(out e);
x = e.tok;
if (la.kind == 28 || la.kind == 46) {
while (la.kind == 46) {
Attribute(ref attrs);
}
Expect(28);
endTok = t; rhss.Add(new ExprRhs(e, attrs));
} else if (la.kind == 22 || la.kind == 25 || la.kind == 95) {
lhss.Add(e);
while (la.kind == 22) {
Get();
Lhs(out e);
lhss.Add(e);
}
if (la.kind == 95) {
Get();
x = t;
Rhs(out r);
rhss.Add(r);
while (la.kind == 22) {
Get();
Rhs(out r);
rhss.Add(r);
}
} else if (la.kind == 25) {
Get();
x = t;
if (la.kind == _assume) {
Expect(31);
suchThatAssume = t;
}
Expression(out suchThat, false, true);
} else SynErr(182);
Expect(28);
endTok = t;
} else if (la.kind == 21) {
Get();
SemErr(t, "invalid statement (did you forget the 'label' keyword?)");
} else SynErr(183);
if (suchThat != null) {
s = new AssignSuchThatStmt(x, endTok, lhss, suchThat, suchThatAssume, null);
} else {
if (lhss.Count == 0 && rhss.Count == 0) {
s = new BlockStmt(x, endTok, new List<Statement>()); // error, give empty statement
} else {
s = new UpdateStmt(x, endTok, lhss, rhss);
}
}
}
void WhileStmt(out Statement stmt)
{
Contract.Ensures(Contract.ValueAtReturn(out stmt) != null); IToken x;
Expression guard = null; IToken guardEllipsis = null;
List<MaybeFreeExpression> invariants = new List<MaybeFreeExpression>();
List<Expression> decreases = new List<Expression>();
Attributes decAttrs = null;
Attributes modAttrs = null;
List<FrameExpression> mod = null;
BlockStmt body = null; IToken bodyEllipsis = null;
IToken bodyStart = null, bodyEnd = null, endTok = Token.NoToken;
List<GuardedAlternative> alternatives;
stmt = dummyStmt; // to please the compiler
bool isDirtyLoop = true;
Expect(99);
x = t;
if (IsLoopSpec() || IsAlternative()) {
while (StartOf(22)) {
LoopSpec(invariants, decreases, ref mod, ref decAttrs, ref modAttrs);
}
AlternativeBlock(false, out alternatives, out endTok);
stmt = new AlternativeLoopStmt(x, endTok, invariants, new Specification<Expression>(decreases, decAttrs), new Specification<FrameExpression>(mod, modAttrs), alternatives);
} else if (StartOf(20)) {
if (StartOf(21)) {
Guard(out guard);
Contract.Assume(guard == null || cce.Owner.None(guard));
} else {
Get();
guardEllipsis = t;
}
while (StartOf(22)) {
LoopSpec(invariants, decreases, ref mod, ref decAttrs, ref modAttrs);
}
if (la.kind == _lbrace) {
BlockStmt(out body, out bodyStart, out bodyEnd);
endTok = body.EndTok; isDirtyLoop = false;
} else if (la.kind == _ellipsis) {
Expect(59);
bodyEllipsis = t; endTok = t; isDirtyLoop = false;
} else if (StartOf(23)) {
} else SynErr(187);
if (guardEllipsis != null || bodyEllipsis != null) {
if (mod != null) {
SemErr(mod[0].E.tok, "'modifies' clauses are not allowed on refining loops");
}
if (body == null && !isDirtyLoop) {
body = new BlockStmt(x, endTok, new List<Statement>());
}
stmt = new WhileStmt(x, endTok, guard, invariants, new Specification<Expression>(decreases, decAttrs), new Specification<FrameExpression>(null, null), body);
stmt = new SkeletonStatement(stmt, guardEllipsis, bodyEllipsis);
} else {
// The following statement protects against crashes in case of parsing errors
if (body == null && !isDirtyLoop) {
body = new BlockStmt(x, endTok, new List<Statement>());
}
stmt = new WhileStmt(x, endTok, guard, invariants, new Specification<Expression>(decreases, decAttrs), new Specification<FrameExpression>(mod, modAttrs), body);
}
} else SynErr(188);
}
public override void Compile_FunctionAsMethod(Function function, Dictionary<TypeParameter,Type> typeArgs,
Dictionary<string,TypeParameter> substArgs)
{
var tok = function.tok;
if (Attributes.Contains(function.Attributes, "CompiledSpec"))
{
string specName = function.Name.Substring("CompiledSpec_".Length);
function = FindFunction(specName);
}
bool hidden = Attributes.Contains(function.Attributes, "opaque");
Formal result = new Formal(function.tok, "__result", function.ResultType, false, function.IsGhost);
string funName = function.Name;
string name = FunName(DafnySpec.SimpleSanitizedName(function));
FunctionCallExpr call = new FunctionCallExpr(tok, name, new ThisExpr(tok), tok,
function.Formals.ConvertAll(f => (Expression)
MakeIdentifierExpr(f.Name, f.Type, f.IsGhost)));
call.Function = function;
call.TypeArgumentSubstitutions = typeArgs;
call.Type = function.ResultType;
CallStmt revealCall = null;
if (hidden)
{
var selectExpr = new MemberSelectExpr(tok, new ThisExpr(tok), "reveal_" + function.Name);
selectExpr.Member = FindMethod(selectExpr.MemberName); // Manually resolve here
selectExpr.TypeApplication = new List<Type>(); // Manually resolve here
selectExpr.Type = new InferredTypeProxy(); // Manually resolve here
revealCall = new CallStmt(tok, tok, new List<Expression>(), selectExpr, new List<Expression>());
revealCall.IsGhost = true;
ClassDecl cls = (ClassDecl)function.EnclosingClass;
string fullName = "#" + function.Name + "_FULL";
function = (Function)cls.Members.Find(m => m.Name == fullName);
if (function == null)
{
throw new Exception("internal error: could not find function " + fullName);
}
substArgs = new Dictionary<string,TypeParameter>();
function.TypeArgs.ForEach(t => substArgs.Add(t.Name, t));
typeArgs = typeArgs.ToDictionary(p => substArgs[p.Key.Name], p => p.Value);
}
Expression funBody = function.Body;
BlockStmt body = null;
if (funBody != null)
{
ReturnStmt retStmt = new ReturnStmt(tok, tok, new List<AssignmentRhs>() {
new ExprRhs(funBody)
});
body = new BlockStmt(tok, tok,
hidden
? (new List<Statement>() { revealCall, retStmt })
: (new List<Statement>() { retStmt }));
}
List<Expression> ens = new List<Expression> {
MakeBinaryExpr(BinaryExpr.Opcode.Eq, BinaryExpr.ResolvedOpcode.EqCommon, Type.Bool,
MakeIdentifierExpr("__result", function.ResultType, function.IsGhost),
call)
}.Concat(function.Ens).ToList();
Method method = new Method(tok, funName, function.IsStatic, function.IsGhost,
function.TypeArgs, function.Formals, new List<Formal> { result },
function.Req.ConvertAll(e => new MaybeFreeExpression(e)),
new Specification<FrameExpression>(new List<FrameExpression>(), null),
ens.ConvertAll(e => new MaybeFreeExpression(e)),
function.Decreases,
body, function.Attributes, function.SignatureEllipsis);
method.EnclosingClass = function.EnclosingClass;
Compile_Method(method, typeArgs);
}
void BlockStmt(out BlockStmt/*!*/ block, out IToken bodyStart, out IToken bodyEnd)
{
Contract.Ensures(Contract.ValueAtReturn(out block) != null);
List<Statement/*!*/> body = new List<Statement/*!*/>();
Expect(46);
bodyStart = t;
while (StartOf(15)) {
Stmt(body);
}
Expect(47);
bodyEnd = t;
block = new BlockStmt(bodyStart, bodyEnd, body);
}
// Find tactic application and resolve it
private void SearchBlockStmt(BlockStmt body) {
Contract.Requires(tcce.NonNull(body));
// TODO Make sure this is an OK Thing to be doing
// Currently, if the proof list is not reset, then because it is static across
// calls, it will start to build up old information, and the program will go
// into a loop trying to figure out new fresh names for 'existing' methods.
BaseSearchStrategy.ResetProofList();
_frame.Push(new Dictionary<IVariable, Type>());
foreach (var stmt in body.Body) {
if (stmt is VarDeclStmt) {
var vds = stmt as VarDeclStmt;
// register local variable declarations
foreach (var local in vds.Locals) {
try {
_frame.Peek().Add(local, local.Type);
} catch (Exception e) {
//TODO: some error handling when target is not resolved
Console.Out.WriteLine(e.Message);
}
}
} else if (stmt is IfStmt) {
var ifStmt = stmt as IfStmt;
SearchIfStmt(ifStmt);
} else if (stmt is WhileStmt) {
var whileStmt = stmt as WhileStmt;
SearchBlockStmt(whileStmt.Body);
} else if (stmt is UpdateStmt) {
var us = stmt as UpdateStmt;
if (_state.IsTacticCall(us)) {
var list = StackToDict(_frame);
var result = ApplyTactic(_state, list, us);
if (result != null)
{
_resultList.Add(us.Copy(), result.GetGeneratedCode().Copy());
}
else
{
//TODO what should go here?
}
}
} else if (stmt is BlockStmt) {
//TODO:
}
}
_frame.Pop();
}
public override BlockStmt CloneBlockStmt(BlockStmt stmt) {
return null;
}
