implement table.fill

src/Language/Wasm/Interpreter.hs

@@ -952,6 +952,23 @@ eval budget store FunctionInstance { funcType, moduleInstance, code = Function {
                     el <- MVector.unsafeRead fromEls (src + off)
                     MVector.unsafeWrite toEls (dst + off) el
                 return $ Done ctx { stack = rest }
+        step ctx@EvalCtx{ stack = (VI32 n:ref:VI32 i:rest) } (TableFill tableIdx) = do
+            let tableAddr = tableaddrs moduleInstance ! fromIntegral tableIdx
+            let TableInstance { items, t } = tableInstances store ! tableAddr
+            let TableType (Limit _ max) _ = t
+            let inc = fromIntegral n
+            let from = fromIntegral i
+            let val = case ref of
+                    RE extRef -> fromIntegral <$> extRef
+                    RF fnRef -> (funcaddrs moduleInstance !) . fromIntegral <$> fnRef
+                    v -> error "Impossible due to validation"
+            els <- readIORef items
+            if from + inc > MVector.length els
+            then return Trap
+            else do
+                Monad.forM_ [0..inc - 1] $ \off ->
+                    MVector.unsafeWrite els (from + off) val
+                return $ Done ctx { stack = rest }
         step ctx@EvalCtx{ stack } (TableSize tableIdx) = do
             let tableAddr = tableaddrs moduleInstance ! fromIntegral tableIdx
             let TableInstance { items } = tableInstances store ! tableAddr

src/Language/Wasm/Parser.y

@@ -482,6 +482,7 @@ plaininstr :: { PlainInstr }
     | 'table.get' opt(index)         { TableGet (fromMaybe (Index 0) $2) }
     | 'table.set' opt(index)         { TableSet (fromMaybe (Index 0) $2) }
     | 'table.copy' opt(index) opt(index) { TableCopy (fromMaybe (Index 0) $2) (fromMaybe (Index 0) $3) }
+    | 'table.fill' opt(index)        { TableFill (fromMaybe (Index 0) $2) }
     | 'table.size' opt(index)        { TableSize (fromMaybe (Index 0) $2) }
     | 'table.grow' opt(index)        { TableGrow (fromMaybe (Index 0) $2) }
     | 'elem.drop' index              { ElemDrop $2 }
@@ -1736,6 +1737,10 @@ desugarize fields = do
             case getTableIndex ctxMod tableIdx of
                 Just tableIdx -> return $ S.TableSize tableIdx
                 Nothing -> Left "unknown table"
+        synInstrToStruct FunCtx { ctxMod } (PlainInstr (TableFill tableIdx)) =
+            case getTableIndex ctxMod tableIdx of
+                Just tableIdx -> return $ S.TableFill tableIdx
+                Nothing -> Left "unknown table"
         synInstrToStruct FunCtx { ctxMod } (PlainInstr (TableGrow tableIdx)) =
             case getTableIndex ctxMod tableIdx of
                 Just tableIdx -> return $ S.TableGrow tableIdx

src/Language/Wasm/Validate.hs

@@ -393,6 +393,11 @@ getInstrType (TableCopy toIdx fromIdx) = do
     let TableType _ toType = tables !! to
     when (fromType /= toType) $ throwError (RefTypeMismatch fromType toType)
     return $ [I32, I32, I32] ==> empty
+getInstrType (TableFill tableIdx) = do
+    Ctx { tables } <- ask
+    when (length tables <= fromIntegral tableIdx) $ throwError (TableIndexOutOfRange tableIdx)
+    let TableType _ tableType = tables !! fromIntegral tableIdx
+    return $ [I32, elemTypeToRefType tableType, I32] ==> empty
 getInstrType (TableSize tableIdx) = do
     Ctx { tables } <- ask
     when (length tables <= fromIntegral tableIdx) $ throwError (TableIndexOutOfRange tableIdx)

tests/Test.hs

@@ -19,7 +19,7 @@ main = do
   files <-
     filter (not . List.isPrefixOf "simd") . filter (List.isSuffixOf ".wast")
       <$> Directory.listDirectory "tests/spec"
-  -- let files = ["ref_func.wast"]
+  -- let files = ["table_fill.wast"]
   scriptTestCases <- (`mapM` files) $ \file -> do
     test <- LBS.readFile ("tests/spec/" ++ file)
     return $ testCase file $ do