From b2c5ef755bc7a2c736c5f52c4753dde66c04c3aa Mon Sep 17 00:00:00 2001 From: tomsmeding Date: Sat, 26 Aug 2017 18:54:41 +0200 Subject: Add break statements --- AST.hs | 5 +++++ BuildIR.hs | 14 +++++++++++++- ProgramParser.hs | 23 ++++++++++++++++++++--- TypeCheck.hs | 33 ++++++++++++++++++++------------- bf.lang | 7 +++---- 5 files changed, 61 insertions(+), 21 deletions(-) diff --git a/AST.hs b/AST.hs index 3e80830..5217d46 100644 --- a/AST.hs +++ b/AST.hs @@ -27,6 +27,7 @@ data Statement | SAs AsExpression Expression | SIf Expression Block Block | SWhile Expression Block + | SBreak Int | SReturn (Maybe Expression) | SExpr Expression deriving (Show, Eq) @@ -111,6 +112,10 @@ instance Pretty Statement where "if " ++ prettyI i c ++ " " ++ prettyI i b1 ++ " else " ++ prettyI i b2 prettyI i (SWhile c b) = "while " ++ prettyI i c ++ " " ++ prettyI i b + prettyI _ (SBreak 0) = + "break;" + prettyI _ (SBreak n) = + "break " ++ show n ++ ";" prettyI _ (SReturn Nothing) = "return;" prettyI i (SReturn (Just e)) = diff --git a/BuildIR.hs b/BuildIR.hs index 665dd33..a4be797 100644 --- a/BuildIR.hs +++ b/BuildIR.hs @@ -21,6 +21,7 @@ type Scope = Map.Map Name (Ref, Type) data BuildState = BuildState { nextId :: Id, scopeStack :: [Scope], + loopStack :: [Id], currentBlock :: Id, blockMap :: Map.Map Id BB } @@ -28,6 +29,7 @@ initBuildState :: BuildState initBuildState = BuildState { nextId = 0, scopeStack = [], + loopStack = [], currentBlock = undefined, blockMap = Map.empty } @@ -81,6 +83,13 @@ getAllBlocks = liftM Map.elems (gets blockMap) switchBlock :: Id -> BuildM () switchBlock bid = modify $ \s -> s {currentBlock = bid} +withLoop :: Id -> BuildM a -> BuildM a +withLoop i act = do + modify $ \s -> s {loopStack = i : loopStack s} + res <- act + modify $ \s -> s {loopStack = tail (loopStack s)} + return res + withScope :: BuildM a -> BuildM a withScope act = do modify $ \s -> s {scopeStack = Map.empty : scopeStack s} @@ -172,9 +181,12 @@ convertStatement (SWhile c b) nextnext = do switchBlock cend setTerm $ IJcc CNeq cref (Constant (refSize cref) 0) body nextnext switchBlock body - convertBlock b bodyend + withLoop nextnext $ convertBlock b bodyend switchBlock bodyend setTerm $ IJmp cond +convertStatement (SBreak n) _ = do + ls <- gets loopStack + setTerm $ IJmp (ls !! n) convertStatement (SReturn Nothing) _ = do setTerm IRet convertStatement (SReturn (Just e)) _ = do diff --git a/ProgramParser.hs b/ProgramParser.hs index 2cacaf5..38da21f 100644 --- a/ProgramParser.hs +++ b/ProgramParser.hs @@ -2,6 +2,7 @@ module ProgramParser(parseProgram) where import Control.Monad import Data.Char +import Data.Maybe import Text.Parsec import qualified Text.Parsec.Expr as E @@ -70,7 +71,7 @@ pBlock = do return $ Block body pStatement :: Parser Statement -pStatement = pSIf <|> pSWhile <|> pSReturn <|> pSDecl <|> pSAs <|> pSExpr +pStatement = pSIf <|> pSWhile <|> pSReturn <|> pSBreak <|> pSDecl <|> pSAs <|> pSExpr pSDecl :: Parser Statement pSDecl = do @@ -112,8 +113,16 @@ pSWhile = do pSReturn :: Parser Statement pSReturn = do symbol "return" - SReturn <$> ((symbol ";" >> return Nothing) <|> - ((Just <$> pExpression) <* symbol ";")) + m <- optionMaybe pExpression + symbol ";" + return $ SReturn m + +pSBreak :: Parser Statement +pSBreak = do + symbol "break" + m <- optionMaybe pIntegerInt + symbol ";" + return $ SBreak (fromMaybe 0 m) pSExpr :: Parser Statement pSExpr = do @@ -231,6 +240,14 @@ pName = do pInteger :: Parser Integer pInteger = read <$> many1 (satisfy isDigit) <* pWhiteComment +pIntegerInt :: Parser Int +pIntegerInt = do + i <- pInteger + when (i > (fromIntegral (maxBound :: Int) :: Integer) || + i < (fromIntegral (minBound :: Int) :: Integer)) $ + unexpected $ "Integer literal " ++ show i ++ " does not fit in an Int" + return $ fromIntegral i + symbol :: String -> Parser () symbol "" = error "symbol \"\"" diff --git a/TypeCheck.hs b/TypeCheck.hs index 36d98c8..13d33c9 100644 --- a/TypeCheck.hs +++ b/TypeCheck.hs @@ -70,24 +70,27 @@ annotateDVar db (DVar toptype name expr) = do else Left $ "Cannot assign a value of type " ++ pretty typ ++ " to a variable of type " ++ pretty toptype +data State = State {stDfunc :: DFunc, stLoopDepth :: Int} + deriving Show + annotateDFunc :: TypeDB -> DFunc -> Error DFunc annotateDFunc db dfunc@(DFunc rettype name arglist block) = do when (name == "main" && rettype /= Just TInt) $ Left $ "Function 'main' should return an int" let db' = foldl registerArg db arglist - block' <- annotateBlock dfunc db' block + block' <- annotateBlock (State dfunc 0) db' block return $ DFunc rettype name arglist block' where registerArg :: TypeDB -> (Type, Name) -> TypeDB registerArg db' (t, n) = dbSet db' n (DBVar t) -annotateBlock :: DFunc -> TypeDB -> Block -> Error Block -annotateBlock dfunc db (Block sts) = +annotateBlock :: State -> TypeDB -> Block -> Error Block +annotateBlock state db (Block sts) = Block . snd <$> foldM (\(db', l) st -> - (\(db'', st') -> (db'', l ++ [st'])) <$> annotateStatement dfunc db' st) + (\(db'', st') -> (db'', l ++ [st'])) <$> annotateStatement state db' st) (db, []) sts -annotateStatement :: DFunc -> TypeDB -> Statement -> Error (TypeDB, Statement) +annotateStatement :: State -> TypeDB -> Statement -> Error (TypeDB, Statement) annotateStatement _ db (SDecl toptype name expr) = do expr' <- annotateExpr db expr when (isNothing (typeof expr')) $ @@ -112,28 +115,32 @@ annotateStatement _ db (SAs ae expr) = do Left $ "Cannot assign a value of type " ++ pretty typ ++ " to a location of type " ++ pretty aetyp return (db, SAs ae' expr') -annotateStatement dfunc db (SIf expr bl1 bl2) = do +annotateStatement st db (SIf expr bl1 bl2) = do expr' <- annotateExpr db expr when (isNothing (typeof expr')) $ Left $ "Cannot use void value in 'if' condition" when (not $ canCoerce (fromJust (typeof expr')) TInt) $ Left $ "Cannot use type " ++ pretty (fromJust (typeof expr')) ++ " in 'if' condition" - bl1' <- withScope db $ flip (annotateBlock dfunc) bl1 - bl2' <- withScope db $ flip (annotateBlock dfunc) bl2 + bl1' <- withScope db $ flip (annotateBlock st) bl1 + bl2' <- withScope db $ flip (annotateBlock st) bl2 return (db, SIf expr' bl1' bl2') -annotateStatement dfunc db (SWhile expr bl) = do +annotateStatement (State dfunc ld) db (SWhile expr bl) = do expr' <- annotateExpr db expr when (isNothing (typeof expr')) $ Left $ "Cannot use void value in 'while' condition" when (not $ canCoerce (fromJust (typeof expr')) TInt) $ Left $ "Cannot use type " ++ pretty (fromJust (typeof expr')) ++ " in 'while' condition" - bl' <- withScope db $ flip (annotateBlock dfunc) bl + bl' <- withScope db $ flip (annotateBlock (State dfunc (ld+1))) bl return (db, SWhile expr' bl') -annotateStatement (DFunc Nothing _ _ _) db (SReturn Nothing) = +annotateStatement (State {stLoopDepth = ld}) db (SBreak n) = + if n > ld + then Left $ "'break " ++ show n ++ "' while in only " ++ show ld ++ " loops" + else return (db, SBreak n) +annotateStatement (State {stDfunc = DFunc Nothing _ _ _}) db (SReturn Nothing) = return (db, SReturn Nothing) -annotateStatement (DFunc (Just _) _ _ _) _ (SReturn Nothing) = +annotateStatement (State {stDfunc = DFunc (Just _) _ _ _}) _ (SReturn Nothing) = Left "Cannot return void value from non-void function" -annotateStatement (DFunc mrt _ _ _) db (SReturn (Just expr)) = do +annotateStatement (State {stDfunc = DFunc mrt _ _ _}) db (SReturn (Just expr)) = do expr' <- annotateExpr db expr case mrt of Nothing -> Left $ "Cannot return non-void value from void function" diff --git a/bf.lang b/bf.lang index 71a5d8a..e2f6788 100644 --- a/bf.lang +++ b/bf.lang @@ -85,17 +85,16 @@ func int main() { char[] source := new char[4088]; int sourcelen := 0; - int done := 0; - while (done != 1) { + while (1) { int c := getc(); // putc(char(c)); if (c < 0) { - done = 1; + break; } else { source[sourcelen] = char(c); sourcelen = sourcelen + 1; if (sourcelen >= bufsize - 1) { - done = 1; + break; } } } -- cgit v1.2.3-54-g00ecf