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authorYuchen Pei <me@ypei.me>2018-01-20 15:41:49 +0100
committerYuchen Pei <me@ypei.me>2018-01-20 15:41:49 +0100
commitd3a0cc3a8ba6dfeb64d3faeffdeb6845b60e5840 (patch)
treed58df9ec2480e2a9ec6240f9c797f83d1a0b1056 /JackCompiler.hs
parent3571f998b28fbc8d9250ba04c983935f10a16c15 (diff)
rearranged the dir for github
- removed tools and pdfs - rearranged the projects dirs - added md files - other minor changes
Diffstat (limited to 'JackCompiler.hs')
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+-- Jack Compiler, as the coursework of Project 11 of Nand2Tetris course (http://nand2tetris.org/).
+-- Author: Yuchen Pei (me@ypei.me)
+-- Date: 2018-01-15
+{-# LANGUAGE FlexibleContexts #-}
+import Text.Parsec.Prim
+import Text.Parsec.Char
+import Text.Parsec.Combinator
+import Data.Functor.Identity
+import Data.Either
+import Data.Maybe
+import Data.List
+import System.Environment
+import System.Directory
+import Control.Monad
+import Data.Char
+import Data.Map (Map)
+import qualified Data.Map as Map
+
+data JClass = JClass JIdentifier [JClassVarDec] [JSubroutineDec] deriving (Show, Eq)
+data JClassVarDec = JClassVarDec JClassVarScope JTypeAndId deriving (Show, Eq)
+data JSubroutineDec = JSubroutineDec JSubroutineHeader JSubroutineBody deriving (Show, Eq)
+data JSubroutineHeader = JSubroutineHeader JSubroutineType JTypeAndId [JTypeAndId] deriving (Show, Eq)
+data JSubroutineBody = JSubroutineBody [JTypeAndId] [JStatement] deriving (Show, Eq)
+data JStatement = JLetStatment JVarId JExpression
+ | JIfStatement JExpression [JStatement] (Maybe [JStatement])
+ | JWhileStatment JExpression [JStatement]
+ | JDoStatement JSubroutineCall
+ | JReturnStatement (Maybe JExpression)
+ deriving (Show, Eq)
+data JExpression = JIntConst Int
+ | JStrConst [Char]
+ | JKeywordConst [Char] -- can only be true, false, null or this
+ | JExpVar JVarId
+ | JExpCall JSubroutineCall
+ | JExpUna JUOp JExpression -- JOp can only be - or ~ here
+ | JExpBin JExpression [(JBOp, JExpression)]
+ deriving (Show, Eq)
+data JVarId = JVarId JIdentifier (Maybe JExpression) deriving (Show, Eq)
+data JSubroutineCall = JSubroutineCall JIdentifier (Maybe JIdentifier) [JExpression] deriving (Show, Eq)
+
+--data ClassTable = C [Char] Table Int deriving (Show, Eq)
+type JBOp = Char
+type JUOp = Char
+type JIdentifier = [Char]
+type JTypeAndId = (JType, JIdentifier)
+type JClassVarScope = [Char]
+type JType = [Char]
+type JSubroutineType = [Char]
+type JackParser = Parsec [Char] ()
+-- For variable tables: map name (type, (seg, n))
+-- For the subroutine table: map name (kind, (type, nArgs))
+type Table = Map [Char] ([Char], ([Char], Int))
+
+
+binaryOpChars = "+-*/&|<>="
+unaryOpChars = "-~"
+keywordConstStrs = ["true", "false", "null", "this"]
+primTypeStrs = ["int", "char", "boolean"]
+primTypeStrs' = primTypeStrs ++ ["void"]
+classVarScopeStrs = ["static", "field"]
+subroutineTypeStrs = ["constructor", "function", "method"]
+alphaUnderscore = ['a' .. 'z'] ++ ['A' .. 'Z'] ++ ['_']
+alphaNumUnderscore = alphaUnderscore ++ ['0'..'9']
+alphaNumUnderscoredot = '.':alphaNumUnderscore
+
+parse' parser = parse parser ""
+
+jackReader = parse' (many jSpace >> jClass)
+
+jClass :: JackParser JClass
+jClass = do
+ string "class" >> many1 jSpace
+ id <- jIdentifier
+ many jSpace >> char '{'
+ classVarDecs <- many $ try (many jSpace >> jClassVarDecs)
+ subroutineDecs <- many $ try (many jSpace >> jSubroutineDec)
+ many jSpace >> char '}'
+ return $ JClass id (mconcat classVarDecs) subroutineDecs
+
+jClassType :: JackParser [Char]
+jClassType = do
+ x <- oneOf ['A' .. 'Z']
+ xs <- many $ oneOf alphaNumUnderscore
+ return $ x:xs
+
+jBOp :: JackParser JBOp
+jBOp = oneOf binaryOpChars
+
+jUOp :: JackParser JUOp
+jUOp = oneOf unaryOpChars
+
+jComment :: JackParser ()
+jComment = jInlineComment <|> jBlockComment
+
+jInlineComment :: JackParser ()
+jInlineComment = return () <*
+ try (string "//" >> manyTill (noneOf "\n\r") endOfLine)
+ --try (string "//" >> manyTill (noneOf "\n") newline)
+
+jSpace :: JackParser ()
+jSpace = (return () <* space) <|> jComment
+
+jBlockComment :: JackParser ()
+jBlockComment = return () <*
+ try (string "/*" >> manyTill anyChar (try $ string "*/"))
+
+jPrimType :: JackParser JType
+jPrimType = choice $ string <$> primTypeStrs
+
+jType :: JackParser JType
+jType = choice [jPrimType, jClassType]
+
+jPrimType' :: JackParser JType
+jPrimType' = choice $ string <$> primTypeStrs'
+
+jType' :: JackParser JType
+jType' = choice [jPrimType', jClassType]
+
+jClassVarScope :: JackParser JClassVarScope
+jClassVarScope = choice $ string <$> classVarScopeStrs
+
+jSubroutineType :: JackParser JSubroutineType
+jSubroutineType = choice $ string <$> subroutineTypeStrs
+
+jIdentifier :: JackParser [Char]
+jIdentifier = do
+ x <- oneOf alphaUnderscore
+ xs <- many $ oneOf alphaNumUnderscore
+ return $ x:xs
+
+jClassVarDecs :: JackParser [JClassVarDec]
+jClassVarDecs = do
+ scope <- jClassVarScope
+ many1 jSpace
+ typeAndIds <- jTypeAndIds
+ many jSpace >> char ';'
+ return $ JClassVarDec scope <$> typeAndIds
+
+jVarDecs :: JackParser [JTypeAndId]
+jVarDecs =
+ (string "var" >> many1 jSpace) >> jTypeAndIds <* (many jSpace >> char ';')
+
+jTypeAndId :: JackParser JType -> JackParser JTypeAndId
+jTypeAndId p = do
+ type_ <- p
+ many1 jSpace
+ id <- jIdentifier
+ return (type_, id)
+
+jTypeAndIds :: JackParser [JTypeAndId]
+jTypeAndIds = do
+ type_ <- jType
+ many1 jSpace
+ ids <- sepBy jIdentifier (try $ many jSpace >> char ',' >> many jSpace)
+ return $ (\x -> (type_, x)) <$> ids
+
+jParameters :: JackParser [JTypeAndId]
+jParameters = do
+ char '(' >> many jSpace
+ params <- sepBy (jTypeAndId jType) (try $ many jSpace >> char ',' >> many jSpace)
+ many jSpace >> char ')'
+ return params
+
+jSubroutineHeader :: JackParser JSubroutineHeader
+jSubroutineHeader = do
+ subtype <- jSubroutineType
+ many1 jSpace
+ typeAndId <- jTypeAndId jType'
+ params <- jParameters
+ return $ JSubroutineHeader subtype typeAndId params
+
+jExpression :: JackParser JExpression
+jExpression = jExpBin <|> jTerm
+
+jTerm :: JackParser JExpression
+jTerm = choice [jIntConst, jStrConst, jKeywordConst, jExpCall, jExpVar, jExpUna, jExpInBraces]
+
+jIntConst :: JackParser JExpression
+jIntConst = JIntConst <$> (read <$> many1 digit)
+
+jStrConst :: JackParser JExpression
+jStrConst = JStrConst <$> between (char '"') (char '"') (many $ noneOf "\"")
+
+jKeywordConst :: JackParser JExpression
+jKeywordConst = JKeywordConst <$> (choice $ try <$> string <$> keywordConstStrs)
+
+jExpVar :: JackParser JExpression
+jExpVar = JExpVar <$> jVarId
+
+jVarId :: JackParser JVarId
+jVarId = do
+ id <- jIdentifier
+ maybeArray <- optionMaybe $ try (char '[' >> jExpression <* char ']')
+ return $ JVarId id maybeArray
+
+jExpCall :: JackParser JExpression
+jExpCall = JExpCall <$> jSubroutineCall
+
+jExpUna :: JackParser JExpression
+jExpUna = do
+ op <- oneOf unaryOpChars
+ many jSpace
+ x <- jTerm
+ return $ JExpUna op x
+
+jExpInBraces :: JackParser JExpression
+jExpInBraces = between (char '(') (char ')') jExpression -- expressions like a + () is not allowed
+
+jExpBin :: JackParser JExpression
+jExpBin = try $ do
+ x <- jTerm
+ xs <- many1 jOpAndTerm
+ return $ JExpBin x xs
+
+jOpAndTerm :: JackParser (JBOp, JExpression)
+jOpAndTerm = do
+ op <- many jSpace >> jBOp
+ x <- many jSpace >> jTerm
+ return (op, x)
+
+jSubroutineDec :: JackParser JSubroutineDec
+jSubroutineDec = do
+ header <- jSubroutineHeader
+ many jSpace
+ body <- jSubroutineBody
+ return $ JSubroutineDec header body
+
+jSubroutineBody :: JackParser JSubroutineBody
+jSubroutineBody = do
+ char '{'
+ varDecs <- many $ try (many jSpace >> jVarDecs)
+ stmts <- many $ try (many jSpace >> jStatement)
+ many jSpace >> char '}'
+ return $ JSubroutineBody (mconcat varDecs) stmts
+
+jStatement :: JackParser JStatement
+jStatement = choice [jLetStatement, jIfStatement, jWhileStatement, jDoStatement, jReturnStatement]
+
+jLetStatement :: JackParser JStatement
+jLetStatement = do
+ string "let" >> many1 jSpace
+ leftVarId <- jVarId
+ many jSpace >> char '=' >> many jSpace
+ exp <- jExpression
+ many jSpace >> char ';'
+ return $ JLetStatment leftVarId exp
+
+jIfStatement = do
+ string "if" >> many jSpace >> char '(' >> many jSpace
+ exp <- jExpression
+ many jSpace >> char ')' >> many jSpace >> char '{' >> many jSpace
+ stmts <- many (try $ many jSpace >> jStatement)
+ many jSpace >> char '}'
+ stmts' <- optionMaybe $ try jElseBlock
+ return $ JIfStatement exp stmts stmts'
+
+jElseBlock :: JackParser [JStatement]
+jElseBlock = do
+ many jSpace >> string "else" >> many jSpace >> char '{' >> many jSpace
+ stmts <- many (try $ many jSpace >> jStatement)
+ many jSpace >> char '}'
+ return stmts
+
+jWhileStatement :: JackParser JStatement
+jWhileStatement = do
+ string "while" >> many jSpace >> char '(' >> many jSpace
+ exp <- jExpression
+ many jSpace >> char ')' >> many jSpace >> char '{'
+ stmts <- many (try $ many jSpace >> jStatement)
+ many jSpace >> char '}'
+ return $ JWhileStatment exp stmts
+
+jDoStatement :: JackParser JStatement
+jDoStatement = do
+ jCall <- string "do" >> many jSpace >> jSubroutineCall
+ many jSpace >> char ';'
+ return $ JDoStatement jCall
+
+jReturnStatement :: JackParser JStatement
+jReturnStatement = do
+ string "return" >> many jSpace
+ res <- optionMaybe $ try jExpression
+ many jSpace >> char ';'
+ return $ JReturnStatement res
+
+jSubroutineCall :: JackParser JSubroutineCall
+jSubroutineCall = try $ do
+ callee <- jIdentifier
+ method <- optionMaybe $ try (char '.' >> jIdentifier)
+ args <- emptyArgs <|> someArgs
+ return $ JSubroutineCall callee method args
+
+emptyArgs :: JackParser [JExpression]
+emptyArgs = return [] <* (try $ char '(' >> many jSpace >> char ')')
+
+someArgs :: JackParser [JExpression]
+someArgs = do
+ char '(' >> many jSpace
+ exps <- sepBy jExpression (many jSpace >> char ',' >> many jSpace)
+ many jSpace >> char ')'
+ return exps
+
+
+-- vm writer starts from here
+
+buildCTable :: [JClassVarDec] -> (Table, Int)
+buildCTable xs = go 0 0 Map.empty xs
+ where go n _ t [] = (t, n)
+ go nField nStatic t ((JClassVarDec "field" (ty, jId)):ys) =
+ go (nField + 1) nStatic (Map.insert jId (ty, ("this", nField)) t) ys
+ go nField nStatic t ((JClassVarDec "static" (ty, jId)):ys) =
+ go nField (nStatic + 1) (Map.insert jId (ty, ("static", nStatic)) t) ys
+
+
+--data JClass = JClass JIdentifier [JClassVarDec] [JSubroutineDec] deriving (Show, Eq)
+buildSRTable :: [JClass] -> Table
+buildSRTable xs = Map.fromList $ mconcat $ go <$> xs where
+ go (JClass cName _ subs) = go' <$> subs where
+ go' (JSubroutineDec (JSubroutineHeader kind (ty, sName) args) _) =
+ (cName ++ "." ++ sName, (kind, (ty, nArgs))) where
+ nArgs = length args + if kind == "method" then 1 else 0
+
+buildLTable :: Bool -> [JTypeAndId] -> [JTypeAndId] -> Table
+buildLTable isMethod args lcls =
+ (go "argument" args (if isMethod then 1 else 0) Map.empty) `Map.union` (go "local" lcls 0 Map.empty) where
+ go _ [] _ t = t
+ go kind ((ty, name):xs) n t = go kind xs (n + 1) $ Map.insert name (ty, (kind, n)) t
+
+--data JSubroutineDec = JSubroutineDec JSubroutineHeader JSubroutineBody deriving (Show, Eq)
+--data JSubroutineHeader = JSubroutineHeader JSubroutineType JTypeAndId [JTypeAndId] deriving (Show, Eq)
+--data JSubroutineBody = JSubroutineBody [JTypeAndId] [JStatement] deriving (Show, Eq)
+
+jackCompiler :: Table -> [[Char]] -> [[Char]]
+jackCompiler initTable = vmWriter initTable . fmap (fromRight (JClass "" [] []) . jackReader)
+
+vmWriter :: Table -> [JClass] -> [[Char]]
+vmWriter initTable xs = vClass (buildSRTable xs `Map.union` initTable) <$> xs
+
+vClass :: Table -> JClass -> [Char]
+vClass u (JClass name vars subs) = mconcat $ vSubroutineDec name t u n <$> subs where
+ (t, n) = buildCTable vars
+
+vSubroutineDec :: [Char] -> Table -> Table -> Int -> JSubroutineDec -> [Char]
+vSubroutineDec cName t u n sub =
+ vFunction (cName ++ "." ++ sName) nLcls ++ kindSpec ++
+ vStatement t s u cName sName 0 stmts where
+ JSubroutineDec (JSubroutineHeader _ (_, sName) args) (JSubroutineBody lcls stmts) = sub
+ nLcls = length lcls
+ kind = fst $ u Map.! (cName ++ "." ++ sName)
+ s = buildLTable (kind == "method") args lcls
+ kindSpec = if kind == "constructor"
+ then vNew n
+ else if kind == "method"
+ then vPush "argument" 0 ++ vPop "pointer" 0
+ else ""
+
+-- data JStatement = JLetStatment JVarId JExpression
+ -- | JIfStatement JExpression [JStatement] (Maybe [JStatement])
+ -- | JWhileStatment JExpression [JStatement]
+ -- | JDoStatement JSubroutineCall
+ -- | JReturnStatement (Maybe JExpression)
+
+vStatement _ _ _ _ _ _ [] = ""
+
+-- vExpression: push the result of exp; vPopToVar: pop to the var addr
+
+vStatement t s u cName name n ((JLetStatment var exp):stmts) =
+ vExpression t s u cName exp ++ vPopToVar t s u cName var ++ vStatement t s u cName name n stmts
+
+vStatement t s u cName name n ((JIfStatement cond thenStmts elseStmts):stmts) =
+ vExpression t s u cName cond ++ vNot ++ vThen thenStmts ++
+ maybe (vLabel labelElse) vElse elseStmts ++ vStatement t s u cName name (n + 1) stmts where
+ labelElse = name ++ ".Else" ++ show n
+ labelEndIf = name ++ ".Endif" ++ show n
+ labelIf = name ++ ".If" ++ show n
+ vThen xs = vIfGoto labelElse ++ vStatement t s u cName labelElse 0 xs
+ vElse xs = vGoto labelEndIf ++ vLabel labelElse ++
+ vStatement t s u cName labelIf 0 xs ++ vLabel labelEndIf
+
+vStatement t s u cName name n ((JWhileStatment cond loopStmts):stmts) =
+ vLabel labelWhile ++ vExpression t s u cName cond ++ vNot ++ vIfGoto labelEndWhile ++
+ vStatement t s u cName labelWhile 0 loopStmts ++ vGoto labelWhile ++
+ vLabel labelEndWhile ++ vStatement t s u cName name (n + 1) stmts where
+ labelWhile = name ++ ".While" ++ show n
+ labelEndWhile = name ++ ".EndWhile" ++ show n
+
+vStatement t s u cName name n ((JDoStatement subCall):stmts) =
+ vSubroutineCall t s u cName subCall ++ vPop "temp" 0 ++ vStatement t s u cName name n stmts
+
+vStatement t s u cName name n ((JReturnStatement ret):stmts) =
+ maybe (vPush "constant" 0) (vExpression t s u cName) ret ++ vReturn ++
+ vStatement t s u cName name n stmts
+
+-- data JExpression = JIntConst Int
+ -- | JStrConst [Char]
+ -- | JKeywordConst [Char] -- can only be true, false, null or this
+ -- | JExpVar JVarId
+ -- | JExpCall JSubroutineCall
+ -- | JExpUna JUOp JExpression -- JOp can only be - or ~ here
+ -- | JExpBin JExpression [(JBOp, JExpression)]
+
+vExpression :: Table -> Table -> Table -> [Char] -> JExpression -> [Char]
+
+vExpression t s _ _ (JIntConst n) = vPush "constant" n
+
+vExpression t s _ _ (JStrConst xs) =
+ vPush "constant" (length xs) ++ vCall "String.new" 1 ++ mconcat (go <$> xs) where
+ go x = vPush "constant" (ord x) ++ vCall "String.appendChar" 2
+
+vExpression t s _ _ (JKeywordConst x)
+ | x == "null" || x == "false" = vPush "constant" 0
+ | x == "true" = vPush "constant" 1 ++ vNeg
+ | x == "this" = vPush "pointer" 0
+
+vExpression t s u cName (JExpVar (JVarId name idx)) = vVar t s u cName name idx vPush
+
+vExpression t s u cName (JExpCall subCall) = vSubroutineCall t s u cName subCall
+
+vExpression t s u cName (JExpUna op exp) = vExpression t s u cName exp ++ vOp op
+ where vOp '~' = vNot; vOp '-' = vNeg;
+
+vExpression t s u cName (JExpBin exp xs) =
+ vExpression t s u cName exp ++ mconcat (go <$> xs)
+ where go (op, exp) = vExpression t s u cName exp ++ vOp op
+ vOp '+' = vAdd; vOp '-' = vSub; vOp '*' = vMul; vOp '/' = vDiv;
+ vOp '&' = vAnd; vOp '|' = vOr; vOp '<' = vLt; vOp '>' = vGt;
+ vOp '=' = vEq;
+
+vPopToVar t s u cName (JVarId name idx) = vVar t s u cName name idx vPop
+
+vVar :: Table -> Table -> Table -> [Char] -> [Char] -> Maybe JExpression -> ([Char] -> Int -> [Char]) -> [Char]
+vVar t s u cName name idx vPushOrPop =
+ let (seg, n) = getSegN t s name in
+ case idx of
+ Nothing -> vPushOrPop seg n
+ Just exp -> vPush seg n ++ vExpression t s u cName exp ++ vAdd
+ ++ vPop "pointer" 1 ++ vPushOrPop "that" 0
+
+
+getRecord :: Table -> Table -> [Char] -> ([Char], ([Char], Int))
+getRecord t s name = case Map.lookup name s of
+ Just x -> x
+ Nothing -> t Map.! name
+
+getSegN :: Table -> Table -> [Char] -> ([Char], Int)
+getSegN t s name = snd $ getRecord t s name
+
+getType :: Table -> Table -> [Char] -> [Char]
+getType t s name = fst $ getRecord t s name
+
+-- data JSubroutineCall = JSubroutineCall JIdentifier (Maybe JIdentifier) [JExpression] deriving (Show, Eq)
+vSubroutineCall t s u cName (JSubroutineCall name name' args) =
+ method ++ mconcat (vExpression t s u cName <$> args) ++ vCall name'' nArgs
+ where
+ name'' = if name' == Nothing
+ then cName ++ "." ++ name
+ else if head name `elem` ['A' .. 'Z']
+ then name ++ "." ++ fromJust name'
+ else getType t s name ++ "." ++ fromJust name'
+ -- u is the SRTable
+ (method, nArgs) =
+ if fst (u Map.! name'') == "method"
+ then if name' == Nothing
+ then (vPush "pointer" 0, length args + 1)
+ else let (seg, n) = getSegN t s name in (vPush seg n, length args + 1)
+ else ("", length args)
+
+vNew n = vPush "constant" n ++ vCall "Memory.alloc" 1 ++ vPop "pointer" 0
+vAdd = "add\n"
+vNot = "not\n"
+vNeg = "neg\n"
+vSub = "sub\n"
+vMul = "call Math.multiply 2\n"
+vDiv = "call Math.divide 2\n"
+vAnd = "and\n"
+vOr = "or\n"
+vLt = "lt\n"
+vGt = "gt\n"
+vEq = "eq\n"
+vReturn = "return\n"
+vLabel xs = "label " ++ xs ++ "\n"
+vGoto xs = "goto " ++ xs ++ "\n"
+vIfGoto xs = "if-goto " ++ xs ++ "\n"
+vFunction xs n = "function " ++ xs ++ " " ++ show n ++ "\n"
+vCall xs n = "call " ++ xs ++ " " ++ show n ++ "\n"
+vPush xs n = "push " ++ xs ++ " " ++ show n ++ "\n"
+vPop xs n = "pop " ++ xs ++ " " ++ show n ++ "\n"
+
+
+-- IO
+
+-- reader of system subroutines' headers
+jClasses :: JackParser [JClass]
+jClasses = many (try $ many jSpace >> jClass)
+
+sysSubroutineTable :: IO Table
+sysSubroutineTable = do
+ x <- readFile "./systemsub.txt"
+ return $ buildSRTable $ head $ rights [parse' jClasses x]
+
+main = do
+ dir <- head <$> getArgs
+ filesWODir <- filter isJackFile <$> listDirectory dir
+ let jackFiles = (dir++) <$> filesWODir
+ codes <- sequence $ readFile <$> jackFiles
+ initTable <- sysSubroutineTable
+ zipWithM writeFile (chExt <$> jackFiles) (jackCompiler initTable codes)
+ where isJackFile xs = drop (length xs - 5) xs == ".jack"
+ chExt xs = take (length xs - 4) xs ++ "vm"
+ --}
+
+
+--testing
+
+testCompiler :: [[Char]] -> IO ()
+testCompiler xs = do
+ initTable <- sysSubroutineTable
+ print $ jackCompiler initTable xs
+
+testCompiler' :: IO ()
+testCompiler' = do
+ --xs <- readFile "./Square/Square.jack"
+ xs <- readFile "./Pong/Ball.jack"
+ testCompiler [xs]
+
+testReader :: IO ()
+testReader = do
+ --xs <- readFile "./Square/Square.jack"
+ xs <- readFile "./Pong/Ball.jack"
+ --print $ buildSRTable $ rights $ [jackReader $ xs]
+ print $ jackReader $ xs
+
+
+--test reader writer x = let Right y = parse' reader x in writer y
+--test' x = let Right y = parse' jStatement x in vStatement Map.empty Map.empty Map.empty "" 0 [y]
+
+