fix multivalue return typecheck and some execution rules

src/Language/Wasm/Interpreter.hs

@@ -636,13 +636,13 @@ eval budget store FunctionInstance { funcType, moduleInstance, code = Function {
         step _ Unreachable = return Trap
         step ctx Nop = return $ Done ctx
         step ctx (Block blockType expr) = do
-            let resType = case blockType of
-                    Inline Nothing -> []
-                    Inline (Just valType) -> [valType]
-                    TypeIndex typeIdx -> results $ funcTypes moduleInstance ! fromIntegral typeIdx
+            let FuncType paramType resType = case blockType of
+                    Inline Nothing -> FuncType [] []
+                    Inline (Just valType) -> FuncType [] [valType]
+                    TypeIndex typeIdx -> funcTypes moduleInstance ! fromIntegral typeIdx
             res <- go ctx { labels = Label resType : labels ctx } expr
             case res of
-                Break 0 r EvalCtx{ locals = ls } -> return $ Done ctx { locals = ls, stack = r ++ stack ctx }
+                Break 0 r EvalCtx{ locals = ls } -> return $ Done ctx { locals = ls, stack = r ++ (drop (length paramType) $ stack ctx) }
                 Break n r ctx' -> return $ Break (n - 1) r ctx'
                 Done ctx'@EvalCtx{ labels = (_:rest) } -> return $ Done ctx' { labels = rest }
                 command -> return command
@@ -653,26 +653,26 @@ eval budget store FunctionInstance { funcType, moduleInstance, code = Function {
                     TypeIndex typeIdx -> results $ funcTypes moduleInstance ! fromIntegral typeIdx
             res <- go ctx { labels = Label resType : labels ctx } expr
             case res of
-                Break 0 r EvalCtx{ locals = ls } -> step ctx { locals = ls, stack = r ++ stack ctx } loop
+                Break 0 r EvalCtx{ locals = ls, stack = st } -> step ctx { locals = ls, stack = st } loop
                 Break n r ctx' -> return $ Break (n - 1) r ctx'
                 Done ctx'@EvalCtx{ labels = (_:rest) } -> return $ Done ctx' { labels = rest }
                 command -> return command
         step ctx@EvalCtx{ stack = (VI32 v): rest } (If blockType true false) = do
-            let resType = case blockType of
-                    Inline Nothing -> []
-                    Inline (Just valType) -> [valType]
-                    TypeIndex typeIdx -> results $ funcTypes moduleInstance ! fromIntegral typeIdx
+            let FuncType paramType resType = case blockType of
+                    Inline Nothing -> FuncType [] []
+                    Inline (Just valType) -> FuncType [] [valType]
+                    TypeIndex typeIdx -> funcTypes moduleInstance ! fromIntegral typeIdx
             let expr = if v /= 0 then true else false
             res <- go ctx { labels = Label resType : labels ctx, stack = rest } expr
             case res of
-                Break 0 r EvalCtx{ locals = ls } -> return $ Done ctx { locals = ls, stack = r ++ rest }
+                Break 0 r EvalCtx{ locals = ls } -> return $ Done ctx { locals = ls, stack = r ++ (drop (length paramType) rest) }
                 Break n r ctx' -> return $ Break (n - 1) r ctx'
                 Done ctx'@EvalCtx{ labels = (_:rest) } -> return $ Done ctx' { labels = rest }
                 command -> return command
         step ctx@EvalCtx{ stack, labels } (Br label) = do
             let idx = fromIntegral label
             let Label resType = labels !! idx
-            case sequence $ zipWith checkValType resType $ take (length resType) stack of
+            case sequence $ zipWith checkValType (reverse resType) $ take (length resType) stack of
                 Just result -> return $ Break idx result ctx
                 Nothing -> return Trap
         step ctx@EvalCtx{ stack = (VI32 v): rest } (BrIf label) =
@@ -685,7 +685,7 @@ eval budget store FunctionInstance { funcType, moduleInstance, code = Function {
             step ctx { stack = rest } (Br lbl)
         step EvalCtx{ stack } Return =
             let resType = results funcType in
-            case sequence $ zipWith checkValType resType $ take (length resType) stack of
+            case sequence $ zipWith checkValType (reverse resType) $ take (length resType) stack of
                 Just result -> return $ ReturnFn $ reverse result
                 Nothing -> return Trap
         step ctx (Call fun) = do

src/Language/Wasm/Validate.hs

@@ -98,7 +98,7 @@ data Arrow = Arrow End End deriving (Show, Eq)
 (==>) a b = Arrow (toEnd a) (toEnd b)
 
 asArrow :: FuncType -> Arrow
-asArrow (FuncType params results) = Arrow (map Val params) (map Val results)
+asArrow (FuncType params results) = Arrow (map Val params) (map Val $ reverse results)
 
 isArrowMatch :: Arrow -> Arrow -> Bool
 isArrowMatch (f `Arrow` t) ( f' `Arrow` t') = isEndMatch f f' && isEndMatch t t'
@@ -210,7 +210,7 @@ getInstrType Block { blockType, body } = do
 getInstrType Loop { blockType, body } = do
     bt@(Arrow from _) <- getBlockType blockType
     resultType <- getResultType blockType
-    t <- withLabel resultType $ getExpressionTypeWithInput from body
+    t <- withLabel [] $ getExpressionTypeWithInput from body
     if isArrowMatch t bt
     then return bt
     else throwError $ TypeMismatch t bt
@@ -404,7 +404,7 @@ replace _ _ [] = []
 replace x y (v:r) = (if x == v then y else v) : replace x y r
 
 getExpressionTypeWithInput :: [VType] -> Expression -> Checker Arrow
-getExpressionTypeWithInput inp = fmap ((inp `Arrow`) . reverse) . foldM go inp
+getExpressionTypeWithInput inp = fmap (inp `Arrow`) . foldM go inp
     where
         go :: [VType] -> Instruction Natural -> Checker [VType]
         go stack instr = do
@@ -485,9 +485,9 @@ isFunctionValid Function {funcType, localTypes = locals, body} mod@Module {types
         let FuncType params results = types !! fromIntegral funcType
         let ctx = ctxFromModule (params ++ locals) [results] results mod
         arr <- runChecker ctx $ getExpressionType body
-        if isArrowMatch arr (empty ==> results)
+        if isArrowMatch arr (empty ==> (reverse results))
         then return ()
-        else Left $ TypeMismatch arr (empty ==> results)
+        else Left $ TypeMismatch arr (empty ==> (reverse results))
     else Left TypeIndexOutOfRange
 
 functionsShouldBeValid :: Validator

tests/Test.hs

@@ -17,7 +17,7 @@ import qualified Data.List as List
 main :: IO ()
 main = do
   files <- filter (List.isSuffixOf ".wast") <$> Directory.listDirectory "tests/spec"
-  -- let files = ["call.wast"]
+  -- let files = ["loop.wast"]
   scriptTestCases <- (`mapM` files) $ \file -> do
     test <- LBS.readFile ("tests/spec/" ++ file)
     return $ testCase file $ do