futhark-0.18.2: src/Language/Futhark/Interpreter.hs
{-# LANGUAGE DeriveTraversable #-}
{-# LANGUAGE GeneralizedNewtypeDeriving #-}
{-# LANGUAGE OverloadedStrings #-}
-- | An interpreter operating on type-checked source Futhark terms.
-- Relatively slow.
module Language.Futhark.Interpreter
( Ctx (..),
Env,
InterpreterError,
initialCtx,
interpretExp,
interpretDec,
interpretImport,
interpretFunction,
ExtOp (..),
BreakReason (..),
StackFrame (..),
typeCheckerEnv,
Value (ValuePrim, ValueArray, ValueRecord),
fromTuple,
isEmptyArray,
prettyEmptyArray,
)
where
import Control.Monad.Except
import Control.Monad.Free.Church
import Control.Monad.Reader
import Control.Monad.State
import Control.Monad.Trans.Maybe
import Data.Array
import Data.Bifunctor (first)
import Data.List
( find,
foldl',
genericLength,
intercalate,
isPrefixOf,
transpose,
)
import qualified Data.List.NonEmpty as NE
import qualified Data.Map as M
import Data.Maybe
import Data.Monoid hiding (Sum)
import Futhark.IR.Primitive (floatValue, intValue)
import qualified Futhark.IR.Primitive as P
import Futhark.Util (chunk, maybeHead, splitFromEnd)
import Futhark.Util.Loc
import Futhark.Util.Pretty hiding (apply, bool)
import Language.Futhark hiding (Value, matchDims)
import qualified Language.Futhark as F
import qualified Language.Futhark.Semantic as T
import Prelude hiding (break, mod)
data StackFrame = StackFrame
{ stackFrameLoc :: Loc,
stackFrameCtx :: Ctx
}
instance Located StackFrame where
locOf = stackFrameLoc
-- | What is the reason for this break point?
data BreakReason
= -- | An explicit breakpoint in the program.
BreakPoint
| -- | A
BreakNaN
data ExtOp a
= ExtOpTrace Loc String a
| ExtOpBreak BreakReason (NE.NonEmpty StackFrame) a
| ExtOpError InterpreterError
instance Functor ExtOp where
fmap f (ExtOpTrace w s x) = ExtOpTrace w s $ f x
fmap f (ExtOpBreak why backtrace x) = ExtOpBreak why backtrace $ f x
fmap _ (ExtOpError err) = ExtOpError err
type Stack = [StackFrame]
type Sizes = M.Map VName Int64
-- | The monad in which evaluation takes place.
newtype EvalM a
= EvalM
( ReaderT
(Stack, M.Map FilePath Env)
(StateT Sizes (F ExtOp))
a
)
deriving
( Monad,
Applicative,
Functor,
MonadFree ExtOp,
MonadReader (Stack, M.Map FilePath Env),
MonadState Sizes
)
runEvalM :: M.Map FilePath Env -> EvalM a -> F ExtOp a
runEvalM imports (EvalM m) = evalStateT (runReaderT m (mempty, imports)) mempty
stacking :: SrcLoc -> Env -> EvalM a -> EvalM a
stacking loc env = local $ \(ss, imports) ->
if isNoLoc loc
then (ss, imports)
else
let s = StackFrame (locOf loc) (Ctx env imports)
in (s : ss, imports)
where
isNoLoc :: SrcLoc -> Bool
isNoLoc = (== NoLoc) . locOf
stacktrace :: EvalM [Loc]
stacktrace = asks $ map stackFrameLoc . fst
lookupImport :: FilePath -> EvalM (Maybe Env)
lookupImport f = asks $ M.lookup f . snd
putExtSize :: VName -> Int64 -> EvalM ()
putExtSize v x = modify $ M.insert v x
getSizes :: EvalM Sizes
getSizes = get
extSizeEnv :: EvalM Env
extSizeEnv = i64Env <$> getSizes
prettyRecord :: Pretty a => M.Map Name a -> Doc
prettyRecord m
| Just vs <- areTupleFields m =
parens $ commasep $ map ppr vs
| otherwise =
braces $ commasep $ map field $ M.toList m
where
field (k, v) = ppr k <+> equals <+> ppr v
valueStructType :: ValueType -> StructType
valueStructType = first (ConstDim . fromIntegral)
-- | A shape is a tree to accomodate the case of records. It is
-- parameterised over the representation of dimensions.
data Shape d
= ShapeDim d (Shape d)
| ShapeLeaf
| ShapeRecord (M.Map Name (Shape d))
| ShapeSum (M.Map Name [Shape d])
deriving (Eq, Show, Functor, Foldable, Traversable)
type ValueShape = Shape Int64
instance Pretty d => Pretty (Shape d) where
ppr ShapeLeaf = mempty
ppr (ShapeDim d s) = brackets (ppr d) <> ppr s
ppr (ShapeRecord m) = prettyRecord m
ppr (ShapeSum cs) =
mconcat (punctuate (text " | ") cs')
where
ppConstr (name, fs) = sep $ (text "#" <> ppr name) : map ppr fs
cs' = map ppConstr $ M.toList cs
emptyShape :: ValueShape -> Bool
emptyShape (ShapeDim d s) = d == 0 || emptyShape s
emptyShape _ = False
typeShape :: M.Map VName (Shape d) -> TypeBase d () -> Shape d
typeShape shapes = go
where
go (Array _ _ et shape) =
foldr ShapeDim (go (Scalar et)) $ shapeDims shape
go (Scalar (Record fs)) =
ShapeRecord $ M.map go fs
go (Scalar (Sum cs)) =
ShapeSum $ M.map (map go) cs
go (Scalar (TypeVar _ _ (TypeName [] v) []))
| Just shape <- M.lookup v shapes =
shape
go _ =
ShapeLeaf
structTypeShape :: M.Map VName ValueShape -> StructType -> Shape (Maybe Int64)
structTypeShape shapes = fmap dim . typeShape shapes'
where
dim (ConstDim d) = Just $ fromIntegral d
dim _ = Nothing
shapes' = M.map (fmap $ ConstDim . fromIntegral) shapes
resolveTypeParams :: [VName] -> StructType -> StructType -> Env
resolveTypeParams names = match
where
match (Scalar (TypeVar _ _ tn _)) t
| typeLeaf tn `elem` names =
typeEnv $ M.singleton (typeLeaf tn) t
match (Scalar (Record poly_fields)) (Scalar (Record fields)) =
mconcat $
M.elems $
M.intersectionWith match poly_fields fields
match (Scalar (Sum poly_fields)) (Scalar (Sum fields)) =
mconcat $
map mconcat $
M.elems $
M.intersectionWith (zipWith match) poly_fields fields
match (Scalar (Arrow _ _ poly_t1 poly_t2)) (Scalar (Arrow _ _ t1 t2)) =
match poly_t1 t1 <> match poly_t2 t2
match poly_t t
| d1 : _ <- shapeDims (arrayShape poly_t),
d2 : _ <- shapeDims (arrayShape t) =
matchDims d1 d2 <> match (stripArray 1 poly_t) (stripArray 1 t)
match _ _ = mempty
matchDims (NamedDim (QualName _ d1)) (ConstDim d2)
| d1 `elem` names =
i64Env $ M.singleton d1 $ fromIntegral d2
matchDims _ _ = mempty
resolveExistentials :: [VName] -> StructType -> ValueShape -> M.Map VName Int64
resolveExistentials names = match
where
match (Scalar (Record poly_fields)) (ShapeRecord fields) =
mconcat $
M.elems $
M.intersectionWith match poly_fields fields
match (Scalar (Sum poly_fields)) (ShapeSum fields) =
mconcat $
map mconcat $
M.elems $
M.intersectionWith (zipWith match) poly_fields fields
match poly_t (ShapeDim d2 rowshape)
| d1 : _ <- shapeDims (arrayShape poly_t) =
matchDims d1 d2 <> match (stripArray 1 poly_t) rowshape
match _ _ = mempty
matchDims (NamedDim (QualName _ d1)) d2
| d1 `elem` names = M.singleton d1 d2
matchDims _ _ = mempty
-- | A fully evaluated Futhark value.
data Value
= ValuePrim !PrimValue
| ValueArray ValueShape !(Array Int Value)
| -- Stores the full shape.
ValueRecord (M.Map Name Value)
| ValueFun (Value -> EvalM Value)
| ValueSum ValueShape Name [Value]
-- Stores the full shape.
instance Eq Value where
ValuePrim (SignedValue x) == ValuePrim (SignedValue y) =
P.doCmpEq (P.IntValue x) (P.IntValue y)
ValuePrim (UnsignedValue x) == ValuePrim (UnsignedValue y) =
P.doCmpEq (P.IntValue x) (P.IntValue y)
ValuePrim (FloatValue x) == ValuePrim (FloatValue y) =
P.doCmpEq (P.FloatValue x) (P.FloatValue y)
ValuePrim (BoolValue x) == ValuePrim (BoolValue y) =
P.doCmpEq (P.BoolValue x) (P.BoolValue y)
ValueArray _ x == ValueArray _ y = x == y
ValueRecord x == ValueRecord y = x == y
ValueSum _ n1 vs1 == ValueSum _ n2 vs2 = n1 == n2 && vs1 == vs2
_ == _ = False
instance Pretty Value where
ppr (ValuePrim v) = ppr v
ppr (ValueArray _ a) =
let elements = elems a -- [Value]
(x : _) = elements
separator = case x of
ValueArray _ _ -> comma <> line
_ -> comma <> space
in brackets $ cat $ punctuate separator (map ppr elements)
ppr (ValueRecord m) = prettyRecord m
ppr ValueFun {} = text "#<fun>"
ppr (ValueSum _ n vs) = text "#" <> sep (ppr n : map ppr vs)
valueShape :: Value -> ValueShape
valueShape (ValueArray shape _) = shape
valueShape (ValueRecord fs) = ShapeRecord $ M.map valueShape fs
valueShape (ValueSum shape _ _) = shape
valueShape _ = ShapeLeaf
checkShape :: Shape (Maybe Int64) -> ValueShape -> Maybe ValueShape
checkShape (ShapeDim Nothing shape1) (ShapeDim d2 shape2) =
ShapeDim d2 <$> checkShape shape1 shape2
checkShape (ShapeDim (Just d1) shape1) (ShapeDim d2 shape2) = do
guard $ d1 == d2
ShapeDim d2 <$> checkShape shape1 shape2
checkShape (ShapeDim d1 shape1) ShapeLeaf =
-- This case is for handling polymorphism, when a function doesn't
-- know that the array it produced actually has more dimensions.
ShapeDim (fromMaybe 0 d1) <$> checkShape shape1 ShapeLeaf
checkShape (ShapeRecord shapes1) (ShapeRecord shapes2) =
ShapeRecord <$> sequence (M.intersectionWith checkShape shapes1 shapes2)
checkShape (ShapeRecord shapes1) ShapeLeaf =
Just $ fromMaybe 0 <$> ShapeRecord shapes1
checkShape (ShapeSum shapes1) (ShapeSum shapes2) =
ShapeSum <$> sequence (M.intersectionWith (zipWithM checkShape) shapes1 shapes2)
checkShape (ShapeSum shapes1) ShapeLeaf =
Just $ fromMaybe 0 <$> ShapeSum shapes1
checkShape _ shape2 =
Just shape2
-- | Does the value correspond to an empty array?
isEmptyArray :: Value -> Bool
isEmptyArray = emptyShape . valueShape
-- | String representation of an empty array with the provided element
-- type. This is pretty ad-hoc - don't expect good results unless the
-- element type is a primitive.
prettyEmptyArray :: TypeBase () () -> Value -> String
prettyEmptyArray t v =
"empty(" ++ dims (valueShape v) ++ pretty t' ++ ")"
where
t' = stripArray (arrayRank t) t
dims (ShapeDim n rowshape) =
"[" ++ pretty n ++ "]" ++ dims rowshape
dims _ = ""
-- | Create an array value; failing if that would result in an
-- irregular array.
mkArray :: TypeBase Int64 () -> [Value] -> Maybe Value
mkArray t [] =
return $ toArray (typeShape mempty t) []
mkArray _ (v : vs) = do
let v_shape = valueShape v
guard $ all ((== v_shape) . valueShape) vs
return $ toArray' v_shape $ v : vs
arrayLength :: Integral int => Array Int Value -> int
arrayLength = fromIntegral . (+ 1) . snd . bounds
toTuple :: [Value] -> Value
toTuple = ValueRecord . M.fromList . zip tupleFieldNames
fromTuple :: Value -> Maybe [Value]
fromTuple (ValueRecord m) = areTupleFields m
fromTuple _ = Nothing
asInteger :: Value -> Integer
asInteger (ValuePrim (SignedValue v)) = P.valueIntegral v
asInteger (ValuePrim (UnsignedValue v)) =
toInteger (P.valueIntegral (P.doZExt v Int64) :: Word64)
asInteger v = error $ "Unexpectedly not an integer: " ++ pretty v
asInt :: Value -> Int
asInt = fromIntegral . asInteger
asSigned :: Value -> IntValue
asSigned (ValuePrim (SignedValue v)) = v
asSigned v = error $ "Unexpected not a signed integer: " ++ pretty v
asInt64 :: Value -> Int64
asInt64 = fromIntegral . asInteger
asBool :: Value -> Bool
asBool (ValuePrim (BoolValue x)) = x
asBool v = error $ "Unexpectedly not a boolean: " ++ pretty v
lookupInEnv ::
(Env -> M.Map VName x) ->
QualName VName ->
Env ->
Maybe x
lookupInEnv onEnv qv env = f env $ qualQuals qv
where
f m (q : qs) =
case M.lookup q $ envTerm m of
Just (TermModule (Module mod)) -> f mod qs
_ -> Nothing
f m [] = M.lookup (qualLeaf qv) $ onEnv m
lookupVar :: QualName VName -> Env -> Maybe TermBinding
lookupVar = lookupInEnv envTerm
lookupType :: QualName VName -> Env -> Maybe T.TypeBinding
lookupType = lookupInEnv envType
-- | A TermValue with a 'Nothing' type annotation is an intrinsic.
data TermBinding
= TermValue (Maybe T.BoundV) Value
| -- | A polymorphic value that must be instantiated.
TermPoly (Maybe T.BoundV) (StructType -> EvalM Value)
| TermModule Module
data Module
= Module Env
| ModuleFun (Module -> EvalM Module)
-- | The actual type- and value environment.
data Env = Env
{ envTerm :: M.Map VName TermBinding,
envType :: M.Map VName T.TypeBinding,
-- | A mapping from type parameters to the shapes of
-- the value to which they were initially bound.
envShapes :: M.Map VName ValueShape
}
instance Monoid Env where
mempty = Env mempty mempty mempty
instance Semigroup Env where
Env vm1 tm1 sm1 <> Env vm2 tm2 sm2 =
Env (vm1 <> vm2) (tm1 <> tm2) (sm1 <> sm2)
-- | An error occurred during interpretation due to an error in the
-- user program. Actual interpreter errors will be signaled with an
-- IO exception ('error').
newtype InterpreterError = InterpreterError String
valEnv :: M.Map VName (Maybe T.BoundV, Value) -> Env
valEnv m =
Env
{ envTerm = M.map (uncurry TermValue) m,
envType = mempty,
envShapes = mempty
}
modEnv :: M.Map VName Module -> Env
modEnv m =
Env
{ envTerm = M.map TermModule m,
envType = mempty,
envShapes = mempty
}
typeEnv :: M.Map VName StructType -> Env
typeEnv m =
Env
{ envTerm = mempty,
envType = M.map tbind m,
envShapes = mempty
}
where
tbind = T.TypeAbbr Unlifted []
i64Env :: M.Map VName Int64 -> Env
i64Env = valEnv . M.map f
where
f x =
( Just $ T.BoundV [] $ Scalar $ Prim $ Signed Int64,
ValuePrim $ SignedValue $ Int64Value x
)
instance Show InterpreterError where
show (InterpreterError s) = s
bad :: SrcLoc -> Env -> String -> EvalM a
bad loc env s = stacking loc env $ do
ss <- map (locStr . srclocOf) <$> stacktrace
liftF $ ExtOpError $ InterpreterError $ "Error at\n" ++ prettyStacktrace 0 ss ++ s
trace :: Value -> EvalM ()
trace v = do
-- We take the second-to-top element of the stack, because any
-- actual call to 'implicits.trace' is going to be in the trace
-- function in the prelude, which is not interesting.
top <- fromMaybe noLoc . maybeHead . drop 1 <$> stacktrace
liftF $ ExtOpTrace top (prettyOneLine v) ()
typeCheckerEnv :: Env -> T.Env
typeCheckerEnv env =
-- FIXME: some shadowing issues are probably not right here.
let valMap (TermValue (Just t) _) = Just t
valMap _ = Nothing
vtable = M.mapMaybe valMap $ envTerm env
nameMap k
| k `M.member` vtable = Just ((T.Term, baseName k), qualName k)
| otherwise = Nothing
in mempty
{ T.envNameMap = M.fromList $ mapMaybe nameMap $ M.keys $ envTerm env,
T.envVtable = vtable
}
break :: EvalM ()
break = do
-- We don't want the env of the function that is calling
-- intrinsics.break, since that is just going to be the boring
-- wrapper function (intrinsics are never called directly).
-- This is why we go a step up the stack.
backtrace <- asks $ drop 1 . fst
case NE.nonEmpty backtrace of
Nothing -> return ()
Just backtrace' -> liftF $ ExtOpBreak BreakPoint backtrace' ()
fromArray :: Value -> (ValueShape, [Value])
fromArray (ValueArray shape as) = (shape, elems as)
fromArray v = error $ "Expected array value, but found: " ++ pretty v
toArray :: ValueShape -> [Value] -> Value
toArray shape vs = ValueArray shape (listArray (0, length vs - 1) vs)
toArray' :: ValueShape -> [Value] -> Value
toArray' rowshape vs = ValueArray shape (listArray (0, length vs - 1) vs)
where
shape = ShapeDim (genericLength vs) rowshape
apply :: SrcLoc -> Env -> Value -> Value -> EvalM Value
apply loc env (ValueFun f) v = stacking loc env (f v)
apply _ _ f _ = error $ "Cannot apply non-function: " ++ pretty f
apply2 :: SrcLoc -> Env -> Value -> Value -> Value -> EvalM Value
apply2 loc env f x y = stacking loc env $ do
f' <- apply noLoc mempty f x
apply noLoc mempty f' y
matchPattern :: Env -> Pattern -> Value -> EvalM Env
matchPattern env p v = do
m <- runMaybeT $ patternMatch env p v
case m of
Nothing -> error $ "matchPattern: missing case for " ++ pretty p ++ " and " ++ pretty v
Just env' -> return env'
patternMatch :: Env -> Pattern -> Value -> MaybeT EvalM Env
patternMatch env (Id v (Info t) _) val =
lift $
pure $
valEnv (M.singleton v (Just $ T.BoundV [] $ toStruct t, val)) <> env
patternMatch env Wildcard {} _ =
lift $ pure env
patternMatch env (TuplePattern ps _) (ValueRecord vs) =
foldM (\env' (p, v) -> patternMatch env' p v) env $
zip ps (map snd $ sortFields vs)
patternMatch env (RecordPattern ps _) (ValueRecord vs) =
foldM (\env' (p, v) -> patternMatch env' p v) env $
M.intersectionWith (,) (M.fromList ps) vs
patternMatch env (PatternParens p _) v = patternMatch env p v
patternMatch env (PatternAscription p _ _) v =
patternMatch env p v
patternMatch env (PatternLit l t _) v = do
l' <- case l of
PatLitInt x -> lift $ eval env $ IntLit x t mempty
PatLitFloat x -> lift $ eval env $ FloatLit x t mempty
PatLitPrim lv -> pure $ ValuePrim lv
if v == l'
then pure env
else mzero
patternMatch env (PatternConstr n _ ps _) (ValueSum _ n' vs)
| n == n' =
foldM (\env' (p, v) -> patternMatch env' p v) env $ zip ps vs
patternMatch _ _ _ = mzero
data Indexing
= IndexingFix Int64
| IndexingSlice (Maybe Int64) (Maybe Int64) (Maybe Int64)
instance Pretty Indexing where
ppr (IndexingFix i) = ppr i
ppr (IndexingSlice i j (Just s)) =
maybe mempty ppr i <> text ":"
<> maybe mempty ppr j
<> text ":"
<> ppr s
ppr (IndexingSlice i (Just j) s) =
maybe mempty ppr i <> text ":"
<> ppr j
<> maybe mempty ((text ":" <>) . ppr) s
ppr (IndexingSlice i Nothing Nothing) =
maybe mempty ppr i <> text ":"
indexesFor ::
Maybe Int64 ->
Maybe Int64 ->
Maybe Int64 ->
Int64 ->
Maybe [Int]
indexesFor start end stride n
| (start', end', stride') <- slice,
end' == start' || signum' (end' - start') == signum' stride',
stride' /= 0,
is <- [start', start' + stride' .. end' - signum stride'],
all inBounds is =
Just $ map fromIntegral is
| otherwise =
Nothing
where
inBounds i = i >= 0 && i < n
slice =
case (start, end, stride) of
(Just start', _, _) ->
let end' = fromMaybe n end
in (start', end', fromMaybe 1 stride)
(Nothing, Just end', _) ->
let start' = 0
in (start', end', fromMaybe 1 stride)
(Nothing, Nothing, Just stride') ->
( if stride' > 0 then 0 else n -1,
if stride' > 0 then n else -1,
stride'
)
(Nothing, Nothing, Nothing) ->
(0, n, 1)
-- | 'signum', but with 0 as 1.
signum' :: (Eq p, Num p) => p -> p
signum' 0 = 1
signum' x = signum x
indexShape :: [Indexing] -> ValueShape -> ValueShape
indexShape (IndexingFix {} : is) (ShapeDim _ shape) =
indexShape is shape
indexShape (IndexingSlice start end stride : is) (ShapeDim d shape) =
ShapeDim n $ indexShape is shape
where
n = maybe 0 genericLength $ indexesFor start end stride d
indexShape _ shape =
shape
indexArray :: [Indexing] -> Value -> Maybe Value
indexArray (IndexingFix i : is) (ValueArray _ arr)
| i >= 0,
i < n =
indexArray is $ arr ! fromIntegral i
| otherwise =
Nothing
where
n = arrayLength arr
indexArray (IndexingSlice start end stride : is) (ValueArray (ShapeDim _ rowshape) arr) = do
js <- indexesFor start end stride $ arrayLength arr
toArray' (indexShape is rowshape) <$> mapM (indexArray is . (arr !)) js
indexArray _ v = Just v
updateArray :: [Indexing] -> Value -> Value -> Maybe Value
updateArray (IndexingFix i : is) (ValueArray shape arr) v
| i >= 0,
i < n = do
v' <- updateArray is (arr ! i') v
Just $ ValueArray shape $ arr // [(i', v')]
| otherwise =
Nothing
where
n = arrayLength arr
i' = fromIntegral i
updateArray (IndexingSlice start end stride : is) (ValueArray shape arr) (ValueArray _ v) = do
arr_is <- indexesFor start end stride $ arrayLength arr
guard $ length arr_is == arrayLength v
let update arr' (i, v') = do
x <- updateArray is (arr ! i) v'
return $ arr' // [(i, x)]
fmap (ValueArray shape) $ foldM update arr $ zip arr_is $ elems v
updateArray _ _ v = Just v
evalDimIndex :: Env -> DimIndex -> EvalM Indexing
evalDimIndex env (DimFix x) =
IndexingFix . asInt64 <$> eval env x
evalDimIndex env (DimSlice start end stride) =
IndexingSlice <$> traverse (fmap asInt64 . eval env) start
<*> traverse (fmap asInt64 . eval env) end
<*> traverse (fmap asInt64 . eval env) stride
evalIndex :: SrcLoc -> Env -> [Indexing] -> Value -> EvalM Value
evalIndex loc env is arr = do
let oob =
bad loc env $
"Index [" <> intercalate ", " (map pretty is)
<> "] out of bounds for array of shape "
<> pretty (valueShape arr)
<> "."
maybe oob return $ indexArray is arr
-- | Expand type based on information that was not available at
-- type-checking time (the structure of abstract types).
evalType :: Env -> StructType -> StructType
evalType _ (Scalar (Prim pt)) = Scalar $ Prim pt
evalType env (Scalar (Record fs)) = Scalar $ Record $ fmap (evalType env) fs
evalType env (Scalar (Arrow () p t1 t2)) =
Scalar $ Arrow () p (evalType env t1) (evalType env t2)
evalType env t@(Array _ u _ shape) =
let et = stripArray (shapeRank shape) t
et' = evalType env et
shape' = fmap evalDim shape
in arrayOf et' shape' u
where
evalDim (NamedDim qn)
| Just (TermValue _ (ValuePrim (SignedValue (Int64Value x)))) <-
lookupVar qn env =
ConstDim $ fromIntegral x
evalDim d = d
evalType env t@(Scalar (TypeVar () _ tn args)) =
case lookupType (qualNameFromTypeName tn) env of
Just (T.TypeAbbr _ ps t') ->
let (substs, types) = mconcat $ zipWith matchPtoA ps args
onDim (NamedDim v) = fromMaybe (NamedDim v) $ M.lookup (qualLeaf v) substs
onDim d = d
in if null ps
then first onDim t'
else evalType (Env mempty types mempty <> env) $ first onDim t'
Nothing -> t
where
matchPtoA (TypeParamDim p _) (TypeArgDim (NamedDim qv) _) =
(M.singleton p $ NamedDim qv, mempty)
matchPtoA (TypeParamDim p _) (TypeArgDim (ConstDim k) _) =
(M.singleton p $ ConstDim k, mempty)
matchPtoA (TypeParamType l p _) (TypeArgType t' _) =
let t'' = evalType env t'
in (mempty, M.singleton p $ T.TypeAbbr l [] t'')
matchPtoA _ _ = mempty
evalType env (Scalar (Sum cs)) = Scalar $ Sum $ (fmap . fmap) (evalType env) cs
evalTermVar :: Env -> QualName VName -> StructType -> EvalM Value
evalTermVar env qv t =
case lookupVar qv env of
Just (TermPoly _ v) -> do
size_env <- extSizeEnv
v $ evalType (size_env <> env) t
Just (TermValue _ v) -> return v
_ -> error $ "`" <> pretty qv <> "` is not bound to a value."
typeValueShape :: Env -> StructType -> EvalM ValueShape
typeValueShape env t = do
size_env <- extSizeEnv
let t' = evalType (size_env <> env) t
case traverse dim $ typeShape mempty t' of
Nothing -> error $ "typeValueShape: failed to fully evaluate type " ++ pretty t'
Just shape -> return shape
where
dim (ConstDim x) = Just $ fromIntegral x
dim _ = Nothing
evalFunction :: Env -> [VName] -> [Pattern] -> Exp -> StructType -> EvalM Value
-- We treat zero-parameter lambdas as simply an expression to
-- evaluate immediately. Note that this is *not* the same as a lambda
-- that takes an empty tuple '()' as argument! Zero-parameter lambdas
-- can never occur in a well-formed Futhark program, but they are
-- convenient in the interpreter.
evalFunction env _ [] body rettype =
-- Eta-expand the rest to make any sizes visible.
etaExpand [] env rettype
where
etaExpand vs env' (Scalar (Arrow _ _ pt rt)) =
return $
ValueFun $ \v -> do
env'' <- matchPattern env' (Wildcard (Info $ fromStruct pt) noLoc) v
etaExpand (v : vs) env'' rt
etaExpand vs env' _ = do
f <- eval env' body
foldM (apply noLoc mempty) f $ reverse vs
evalFunction env missing_sizes (p : ps) body rettype =
return $
ValueFun $ \v -> do
env' <- matchPattern env p v
-- Fix up the last sizes, if any.
let env''
| null missing_sizes = env'
| otherwise =
env'
<> i64Env
( resolveExistentials
missing_sizes
(patternStructType p)
(valueShape v)
)
evalFunction env'' missing_sizes ps body rettype
evalFunctionBinding ::
Env ->
[TypeParam] ->
[Pattern] ->
StructType ->
[VName] ->
Exp ->
EvalM TermBinding
evalFunctionBinding env tparams ps ret retext fbody = do
let ret' = evalType env ret
arrow (xp, xt) yt = Scalar $ Arrow () xp xt yt
ftype = foldr (arrow . patternParam) ret' ps
-- Distinguish polymorphic and non-polymorphic bindings here.
if null tparams
then
TermValue (Just $ T.BoundV [] ftype)
<$> (returned env ret retext =<< evalFunction env [] ps fbody ret')
else return $
TermPoly (Just $ T.BoundV [] ftype) $ \ftype' -> do
let tparam_names = map typeParamName tparams
env' = resolveTypeParams tparam_names ftype ftype' <> env
-- In some cases (abstract lifted types) there may be
-- missing sizes that were not fixed by the type
-- instantiation. These will have to be set by looking
-- at the actual function arguments.
missing_sizes =
filter (`M.notMember` envTerm env') $
map typeParamName (filter isSizeParam tparams)
returned env ret retext =<< evalFunction env' missing_sizes ps fbody ret'
evalArg :: Env -> Exp -> Maybe VName -> EvalM Value
evalArg env e ext = do
v <- eval env e
case ext of
Just ext' -> putExtSize ext' $ asInt64 v
Nothing -> return ()
return v
returned :: Env -> TypeBase (DimDecl VName) als -> [VName] -> Value -> EvalM Value
returned _ _ [] v = return v
returned env ret retext v = do
mapM_ (uncurry putExtSize) $
M.toList $
resolveExistentials retext (evalType env $ toStruct ret) $ valueShape v
return v
eval :: Env -> Exp -> EvalM Value
eval _ (Literal v _) = return $ ValuePrim v
eval env (Parens e _) = eval env e
eval env (QualParens (qv, _) e loc) = do
m <- evalModuleVar env qv
case m of
ModuleFun {} -> error $ "Local open of module function at " ++ locStr loc
Module m' -> eval (m' <> env) e
eval env (TupLit vs _) = toTuple <$> mapM (eval env) vs
eval env (RecordLit fields _) =
ValueRecord . M.fromList <$> mapM evalField fields
where
evalField (RecordFieldExplicit k e _) = do
v <- eval env e
return (k, v)
evalField (RecordFieldImplicit k t loc) = do
v <- eval env $ Var (qualName k) t loc
return (baseName k, v)
eval _ (StringLit vs _) =
return $
toArray' ShapeLeaf $
map (ValuePrim . UnsignedValue . Int8Value . fromIntegral) vs
eval env (ArrayLit [] (Info t) _) = do
t' <- typeValueShape env $ toStruct t
return $ toArray t' []
eval env (ArrayLit (v : vs) _ _) = do
v' <- eval env v
vs' <- mapM (eval env) vs
return $ toArray' (valueShape v') (v' : vs')
eval env (Range start maybe_second end (Info t, Info retext) loc) = do
start' <- asInteger <$> eval env start
maybe_second' <- traverse (fmap asInteger . eval env) maybe_second
end' <- traverse (fmap asInteger . eval env) end
let (end_adj, step, ok) =
case (end', maybe_second') of
(DownToExclusive end'', Nothing) ->
(end'' + 1, -1, start' >= end'')
(DownToExclusive end'', Just second') ->
(end'' + 1, second' - start', start' >= end'' && second' < start')
(ToInclusive end'', Nothing) ->
(end'', 1, start' <= end'')
(ToInclusive end'', Just second')
| second' > start' ->
(end'', second' - start', start' <= end'')
| otherwise ->
(end'', second' - start', start' >= end'' && second' /= start')
(UpToExclusive x, Nothing) ->
(x -1, 1, start' <= x)
(UpToExclusive x, Just second') ->
(x -1, second' - start', start' <= x && second' > start')
if ok
then
returned env t retext $
toArray' ShapeLeaf $ map toInt [start', start' + step .. end_adj]
else bad loc env $ badRange start' maybe_second' end'
where
toInt =
case stripArray 1 t of
Scalar (Prim (Signed t')) ->
ValuePrim . SignedValue . intValue t'
Scalar (Prim (Unsigned t')) ->
ValuePrim . UnsignedValue . intValue t'
_ -> error $ "Nonsensical range type: " ++ show t
badRange start' maybe_second' end' =
"Range " ++ pretty start'
++ ( case maybe_second' of
Nothing -> ""
Just second' -> ".." ++ pretty second'
)
++ ( case end' of
DownToExclusive x -> "..>" ++ pretty x
ToInclusive x -> "..." ++ pretty x
UpToExclusive x -> "..<" ++ pretty x
)
++ " is invalid."
eval env (Var qv (Info t) _) = evalTermVar env qv (toStruct t)
eval env (Ascript e _ _) = eval env e
eval env (Coerce e td (Info ret, Info retext) loc) = do
v <- returned env ret retext =<< eval env e
let t = evalType env $ unInfo $ expandedType td
case checkShape (structTypeShape (envShapes env) t) (valueShape v) of
Just _ -> return v
Nothing ->
bad loc env $
"Value `" <> pretty v <> "` of shape `" ++ pretty (valueShape v)
++ "` cannot match shape of type `"
<> pretty (declaredType td)
<> "` (`"
<> pretty t
<> "`)"
eval env (LetPat p e body (Info ret, Info retext) _) = do
v <- eval env e
env' <- matchPattern env p v
returned env ret retext =<< eval env' body
eval env (LetFun f (tparams, ps, _, Info ret, fbody) body _ _) = do
binding <- evalFunctionBinding env tparams ps ret [] fbody
eval (env {envTerm = M.insert f binding $ envTerm env}) body
eval _ (IntLit v (Info t) _) =
case t of
Scalar (Prim (Signed it)) ->
return $ ValuePrim $ SignedValue $ intValue it v
Scalar (Prim (Unsigned it)) ->
return $ ValuePrim $ UnsignedValue $ intValue it v
Scalar (Prim (FloatType ft)) ->
return $ ValuePrim $ FloatValue $ floatValue ft v
_ -> error $ "eval: nonsensical type for integer literal: " ++ pretty t
eval _ (FloatLit v (Info t) _) =
case t of
Scalar (Prim (FloatType ft)) ->
return $ ValuePrim $ FloatValue $ floatValue ft v
_ -> error $ "eval: nonsensical type for float literal: " ++ pretty t
eval
env
( BinOp
(op, _)
op_t
(x, Info (_, xext))
(y, Info (_, yext))
(Info t)
(Info retext)
loc
)
| baseString (qualLeaf op) == "&&" = do
x' <- asBool <$> eval env x
if x'
then eval env y
else return $ ValuePrim $ BoolValue False
| baseString (qualLeaf op) == "||" = do
x' <- asBool <$> eval env x
if x'
then return $ ValuePrim $ BoolValue True
else eval env y
| otherwise = do
op' <- eval env $ Var op op_t loc
x' <- evalArg env x xext
y' <- evalArg env y yext
returned env t retext =<< apply2 loc env op' x' y'
eval env (If cond e1 e2 (Info ret, Info retext) _) = do
cond' <- asBool <$> eval env cond
returned env ret retext
=<< if cond' then eval env e1 else eval env e2
eval env (Apply f x (Info (_, ext)) (Info t, Info retext) loc) = do
-- It is important that 'x' is evaluated first in order to bring any
-- sizes into scope that may be used in the type of 'f'.
x' <- evalArg env x ext
f' <- eval env f
returned env t retext =<< apply loc env f' x'
eval env (Negate e _) = do
ev <- eval env e
ValuePrim <$> case ev of
ValuePrim (SignedValue (Int8Value v)) -> return $ SignedValue $ Int8Value (- v)
ValuePrim (SignedValue (Int16Value v)) -> return $ SignedValue $ Int16Value (- v)
ValuePrim (SignedValue (Int32Value v)) -> return $ SignedValue $ Int32Value (- v)
ValuePrim (SignedValue (Int64Value v)) -> return $ SignedValue $ Int64Value (- v)
ValuePrim (UnsignedValue (Int8Value v)) -> return $ UnsignedValue $ Int8Value (- v)
ValuePrim (UnsignedValue (Int16Value v)) -> return $ UnsignedValue $ Int16Value (- v)
ValuePrim (UnsignedValue (Int32Value v)) -> return $ UnsignedValue $ Int32Value (- v)
ValuePrim (UnsignedValue (Int64Value v)) -> return $ UnsignedValue $ Int64Value (- v)
ValuePrim (FloatValue (Float32Value v)) -> return $ FloatValue $ Float32Value (- v)
ValuePrim (FloatValue (Float64Value v)) -> return $ FloatValue $ Float64Value (- v)
_ -> error $ "Cannot negate " ++ pretty ev
eval env (Index e is (Info t, Info retext) loc) = do
is' <- mapM (evalDimIndex env) is
arr <- eval env e
returned env t retext =<< evalIndex loc env is' arr
eval env (Update src is v loc) =
maybe oob return
=<< updateArray <$> mapM (evalDimIndex env) is <*> eval env src <*> eval env v
where
oob = bad loc env "Bad update"
eval env (RecordUpdate src all_fs v _ _) =
update <$> eval env src <*> pure all_fs <*> eval env v
where
update _ [] v' = v'
update (ValueRecord src') (f : fs) v'
| Just f_v <- M.lookup f src' =
ValueRecord $ M.insert f (update f_v fs v') src'
update _ _ _ = error "eval RecordUpdate: invalid value."
eval env (LetWith dest src is v body _ loc) = do
let Ident src_vn (Info src_t) _ = src
dest' <-
maybe oob return
=<< updateArray <$> mapM (evalDimIndex env) is
<*> evalTermVar env (qualName src_vn) (toStruct src_t)
<*> eval env v
let t = T.BoundV [] $ toStruct $ unInfo $ identType dest
eval (valEnv (M.singleton (identName dest) (Just t, dest')) <> env) body
where
oob = bad loc env "Bad update"
-- We treat zero-parameter lambdas as simply an expression to
-- evaluate immediately. Note that this is *not* the same as a lambda
-- that takes an empty tuple '()' as argument! Zero-parameter lambdas
-- can never occur in a well-formed Futhark program, but they are
-- convenient in the interpreter.
eval env (Lambda ps body _ (Info (_, rt)) _) =
evalFunction env [] ps body rt
eval env (OpSection qv (Info t) _) = evalTermVar env qv $ toStruct t
eval env (OpSectionLeft qv _ e (Info (_, argext), _) (Info t, Info retext) loc) = do
v <- evalArg env e argext
f <- evalTermVar env qv (toStruct t)
returned env t retext =<< apply loc env f v
eval env (OpSectionRight qv _ e (Info _, Info (_, argext)) (Info t) loc) = do
y <- evalArg env e argext
return $
ValueFun $ \x -> do
f <- evalTermVar env qv $ toStruct t
apply2 loc env f x y
eval env (IndexSection is _ loc) = do
is' <- mapM (evalDimIndex env) is
return $ ValueFun $ evalIndex loc env is'
eval _ (ProjectSection ks _ _) =
return $ ValueFun $ flip (foldM walk) ks
where
walk (ValueRecord fs) f
| Just v' <- M.lookup f fs = return v'
walk _ _ = error "Value does not have expected field."
eval env (DoLoop sparams pat init_e form body (Info (ret, retext)) _) = do
init_v <- eval env init_e
returned env ret retext
=<< case form of
For iv bound -> do
bound' <- asSigned <$> eval env bound
forLoop (identName iv) bound' (zero bound') init_v
ForIn in_pat in_e -> do
(_, in_vs) <- fromArray <$> eval env in_e
foldM (forInLoop in_pat) init_v in_vs
While cond ->
whileLoop cond init_v
where
withLoopParams v =
let sparams' =
resolveExistentials
sparams
(patternStructType pat)
(valueShape v)
in matchPattern (i64Env sparams' <> env) pat v
inc = (`P.doAdd` Int64Value 1)
zero = (`P.doMul` Int64Value 0)
forLoop iv bound i v
| i >= bound = return v
| otherwise = do
env' <- withLoopParams v
forLoop iv bound (inc i)
=<< eval
( valEnv
( M.singleton
iv
( Just $ T.BoundV [] $ Scalar $ Prim $ Signed Int64,
ValuePrim (SignedValue i)
)
)
<> env'
)
body
whileLoop cond v = do
env' <- withLoopParams v
continue <- asBool <$> eval env' cond
if continue
then whileLoop cond =<< eval env' body
else return v
forInLoop in_pat v in_v = do
env' <- withLoopParams v
env'' <- matchPattern env' in_pat in_v
eval env'' body
eval env (Project f e _ _) = do
v <- eval env e
case v of
ValueRecord fs | Just v' <- M.lookup f fs -> return v'
_ -> error "Value does not have expected field."
eval env (Assert what e (Info s) loc) = do
cond <- asBool <$> eval env what
unless cond $ bad loc env s
eval env e
eval env (Constr c es (Info t) _) = do
vs <- mapM (eval env) es
shape <- typeValueShape env $ toStruct t
return $ ValueSum shape c vs
eval env (Match e cs (Info ret, Info retext) _) = do
v <- eval env e
returned env ret retext =<< match v (NE.toList cs)
where
match _ [] =
error "Pattern match failure."
match v (c : cs') = do
c' <- evalCase v env c
case c' of
Just v' -> return v'
Nothing -> match v cs'
eval env (Attr _ e _) = eval env e
evalCase ::
Value ->
Env ->
CaseBase Info VName ->
EvalM (Maybe Value)
evalCase v env (CasePat p cExp _) = runMaybeT $ do
env' <- patternMatch env p v
lift $ eval env' cExp
substituteInModule :: M.Map VName VName -> Module -> Module
substituteInModule substs = onModule
where
rev_substs = reverseSubstitutions substs
replace v = fromMaybe v $ M.lookup v rev_substs
replaceQ v = maybe v qualName $ M.lookup (qualLeaf v) rev_substs
replaceM f m = M.fromList $ do
(k, v) <- M.toList m
return (replace k, f v)
onModule (Module (Env terms types _)) =
Module $ Env (replaceM onTerm terms) (replaceM onType types) mempty
onModule (ModuleFun f) =
ModuleFun $ \m -> onModule <$> f (substituteInModule rev_substs m)
onTerm (TermValue t v) = TermValue t v
onTerm (TermPoly t v) = TermPoly t v
onTerm (TermModule m) = TermModule $ onModule m
onType (T.TypeAbbr l ps t) = T.TypeAbbr l ps $ first onDim t
onDim (NamedDim v) = NamedDim $ replaceQ v
onDim (ConstDim x) = ConstDim x
onDim AnyDim = AnyDim
reverseSubstitutions :: M.Map VName VName -> M.Map VName VName
reverseSubstitutions = M.fromList . map (uncurry $ flip (,)) . M.toList
evalModuleVar :: Env -> QualName VName -> EvalM Module
evalModuleVar env qv =
case lookupVar qv env of
Just (TermModule m) -> return m
_ -> error $ quote (pretty qv) <> " is not bound to a module."
evalModExp :: Env -> ModExp -> EvalM Module
evalModExp _ (ModImport _ (Info f) _) = do
f' <- lookupImport f
case f' of
Nothing -> error $ "Unknown import " ++ show f
Just m -> return $ Module m
evalModExp env (ModDecs ds _) = do
Env terms types _ <- foldM evalDec env ds
-- Remove everything that was present in the original Env.
return $
Module $
Env
(terms `M.difference` envTerm env)
(types `M.difference` envType env)
mempty
evalModExp env (ModVar qv _) =
evalModuleVar env qv
evalModExp env (ModAscript me _ (Info substs) _) =
substituteInModule substs <$> evalModExp env me
evalModExp env (ModParens me _) = evalModExp env me
evalModExp env (ModLambda p ret e loc) =
return $
ModuleFun $ \am -> do
let env' = env {envTerm = M.insert (modParamName p) (TermModule am) $ envTerm env}
evalModExp env' $ case ret of
Nothing -> e
Just (se, rsubsts) -> ModAscript e se rsubsts loc
evalModExp env (ModApply f e (Info psubst) (Info rsubst) _) = do
f' <- evalModExp env f
case f' of
ModuleFun f'' -> do
e' <- evalModExp env e
substituteInModule rsubst <$> f'' (substituteInModule psubst e')
_ -> error "Expected ModuleFun."
evalDec :: Env -> Dec -> EvalM Env
evalDec env (ValDec (ValBind _ v _ (Info (ret, retext)) tparams ps fbody _ _ _)) = do
binding <- evalFunctionBinding env tparams ps ret retext fbody
return $ env {envTerm = M.insert v binding $ envTerm env}
evalDec env (OpenDec me _) = do
me' <- evalModExp env me
case me' of
Module me'' -> return $ me'' <> env
_ -> error "Expected Module"
evalDec env (ImportDec name name' loc) =
evalDec env $ LocalDec (OpenDec (ModImport name name' loc) loc) loc
evalDec env (LocalDec d _) = evalDec env d
evalDec env SigDec {} = return env
evalDec env (TypeDec (TypeBind v l ps t _ _)) = do
let abbr =
T.TypeAbbr l ps $
evalType env $ unInfo $ expandedType t
return env {envType = M.insert v abbr $ envType env}
evalDec env (ModDec (ModBind v ps ret body _ loc)) = do
mod <- evalModExp env $ wrapInLambda ps
return $ modEnv (M.singleton v mod) <> env
where
wrapInLambda [] = case ret of
Just (se, substs) -> ModAscript body se substs loc
Nothing -> body
wrapInLambda [p] = ModLambda p ret body loc
wrapInLambda (p : ps') = ModLambda p Nothing (wrapInLambda ps') loc
-- | The interpreter context. All evaluation takes place with respect
-- to a context, and it can be extended with more definitions, which
-- is how the REPL works.
data Ctx = Ctx
{ ctxEnv :: Env,
ctxImports :: M.Map FilePath Env
}
nanValue :: PrimValue -> Bool
nanValue (FloatValue v) =
case v of
Float32Value x -> isNaN x
Float64Value x -> isNaN x
nanValue _ = False
breakOnNaN :: [PrimValue] -> PrimValue -> EvalM ()
breakOnNaN inputs result
| not (any nanValue inputs) && nanValue result = do
backtrace <- asks fst
case NE.nonEmpty backtrace of
Nothing -> return ()
Just backtrace' -> liftF $ ExtOpBreak BreakNaN backtrace' ()
breakOnNaN _ _ =
return ()
-- | The initial environment contains definitions of the various intrinsic functions.
initialCtx :: Ctx
initialCtx =
Ctx
( Env
( M.insert
(VName (nameFromString "intrinsics") 0)
(TermModule (Module $ Env terms types mempty))
terms
)
types
mempty
)
mempty
where
terms = M.mapMaybeWithKey (const . def . baseString) intrinsics
types = M.mapMaybeWithKey (const . tdef . baseString) intrinsics
sintOp f =
[ (getS, putS, P.doBinOp (f Int8)),
(getS, putS, P.doBinOp (f Int16)),
(getS, putS, P.doBinOp (f Int32)),
(getS, putS, P.doBinOp (f Int64))
]
uintOp f =
[ (getU, putU, P.doBinOp (f Int8)),
(getU, putU, P.doBinOp (f Int16)),
(getU, putU, P.doBinOp (f Int32)),
(getU, putU, P.doBinOp (f Int64))
]
intOp f = sintOp f ++ uintOp f
floatOp f =
[ (getF, putF, P.doBinOp (f Float32)),
(getF, putF, P.doBinOp (f Float64))
]
arithOp f g = Just $ bopDef $ intOp f ++ floatOp g
flipCmps = map (\(f, g, h) -> (f, g, flip h))
sintCmp f =
[ (getS, Just . BoolValue, P.doCmpOp (f Int8)),
(getS, Just . BoolValue, P.doCmpOp (f Int16)),
(getS, Just . BoolValue, P.doCmpOp (f Int32)),
(getS, Just . BoolValue, P.doCmpOp (f Int64))
]
uintCmp f =
[ (getU, Just . BoolValue, P.doCmpOp (f Int8)),
(getU, Just . BoolValue, P.doCmpOp (f Int16)),
(getU, Just . BoolValue, P.doCmpOp (f Int32)),
(getU, Just . BoolValue, P.doCmpOp (f Int64))
]
floatCmp f =
[ (getF, Just . BoolValue, P.doCmpOp (f Float32)),
(getF, Just . BoolValue, P.doCmpOp (f Float64))
]
boolCmp f = [(getB, Just . BoolValue, P.doCmpOp f)]
getV (SignedValue x) = Just $ P.IntValue x
getV (UnsignedValue x) = Just $ P.IntValue x
getV (FloatValue x) = Just $ P.FloatValue x
getV (BoolValue x) = Just $ P.BoolValue x
putV (P.IntValue x) = SignedValue x
putV (P.FloatValue x) = FloatValue x
putV (P.BoolValue x) = BoolValue x
putV P.Checked = BoolValue True
getS (SignedValue x) = Just $ P.IntValue x
getS _ = Nothing
putS (P.IntValue x) = Just $ SignedValue x
putS _ = Nothing
getU (UnsignedValue x) = Just $ P.IntValue x
getU _ = Nothing
putU (P.IntValue x) = Just $ UnsignedValue x
putU _ = Nothing
getF (FloatValue x) = Just $ P.FloatValue x
getF _ = Nothing
putF (P.FloatValue x) = Just $ FloatValue x
putF _ = Nothing
getB (BoolValue x) = Just $ P.BoolValue x
getB _ = Nothing
putB (P.BoolValue x) = Just $ BoolValue x
putB _ = Nothing
fun1 f =
TermValue Nothing $ ValueFun $ \x -> f x
fun2 f =
TermValue Nothing $
ValueFun $ \x ->
return $ ValueFun $ \y -> f x y
fun2t f =
TermValue Nothing $
ValueFun $ \v ->
case fromTuple v of
Just [x, y] -> f x y
_ -> error $ "Expected pair; got: " ++ pretty v
fun3t f =
TermValue Nothing $
ValueFun $ \v ->
case fromTuple v of
Just [x, y, z] -> f x y z
_ -> error $ "Expected triple; got: " ++ pretty v
fun6t f =
TermValue Nothing $
ValueFun $ \v ->
case fromTuple v of
Just [x, y, z, a, b, c] -> f x y z a b c
_ -> error $ "Expected sextuple; got: " ++ pretty v
bopDef fs = fun2 $ \x y ->
case (x, y) of
(ValuePrim x', ValuePrim y')
| Just z <- msum $ map (`bopDef'` (x', y')) fs -> do
breakOnNaN [x', y'] z
return $ ValuePrim z
_ ->
bad noLoc mempty $
"Cannot apply operator to arguments "
<> quote (pretty x)
<> " and "
<> quote (pretty y)
<> "."
where
bopDef' (valf, retf, op) (x, y) = do
x' <- valf x
y' <- valf y
retf =<< op x' y'
unopDef fs = fun1 $ \x ->
case x of
(ValuePrim x')
| Just r <- msum $ map (`unopDef'` x') fs -> do
breakOnNaN [x'] r
return $ ValuePrim r
_ ->
bad noLoc mempty $
"Cannot apply function to argument "
<> quote (pretty x)
<> "."
where
unopDef' (valf, retf, op) x = do
x' <- valf x
retf =<< op x'
tbopDef f = fun1 $ \v ->
case fromTuple v of
Just [ValuePrim x, ValuePrim y]
| Just x' <- getV x,
Just y' <- getV y,
Just z <- putV <$> f x' y' -> do
breakOnNaN [x, y] z
return $ ValuePrim z
_ ->
bad noLoc mempty $
"Cannot apply operator to argument "
<> quote (pretty v)
<> "."
def "!" =
Just $
unopDef
[ (getS, putS, P.doUnOp $ P.Complement Int8),
(getS, putS, P.doUnOp $ P.Complement Int16),
(getS, putS, P.doUnOp $ P.Complement Int32),
(getS, putS, P.doUnOp $ P.Complement Int64),
(getU, putU, P.doUnOp $ P.Complement Int8),
(getU, putU, P.doUnOp $ P.Complement Int16),
(getU, putU, P.doUnOp $ P.Complement Int32),
(getU, putU, P.doUnOp $ P.Complement Int64),
(getB, putB, P.doUnOp P.Not)
]
def "+" = arithOp (`P.Add` P.OverflowWrap) P.FAdd
def "-" = arithOp (`P.Sub` P.OverflowWrap) P.FSub
def "*" = arithOp (`P.Mul` P.OverflowWrap) P.FMul
def "**" = arithOp P.Pow P.FPow
def "/" =
Just $
bopDef $
sintOp (`P.SDiv` P.Unsafe)
++ uintOp (`P.UDiv` P.Unsafe)
++ floatOp P.FDiv
def "%" =
Just $
bopDef $
sintOp (`P.SMod` P.Unsafe)
++ uintOp (`P.UMod` P.Unsafe)
++ floatOp P.FMod
def "//" =
Just $
bopDef $
sintOp (`P.SQuot` P.Unsafe)
++ uintOp (`P.UDiv` P.Unsafe)
def "%%" =
Just $
bopDef $
sintOp (`P.SRem` P.Unsafe)
++ uintOp (`P.UMod` P.Unsafe)
def "^" = Just $ bopDef $ intOp P.Xor
def "&" = Just $ bopDef $ intOp P.And
def "|" = Just $ bopDef $ intOp P.Or
def ">>" = Just $ bopDef $ sintOp P.AShr ++ uintOp P.LShr
def "<<" = Just $ bopDef $ intOp P.Shl
def ">>>" = Just $ bopDef $ sintOp P.LShr ++ uintOp P.LShr
def "==" = Just $
fun2 $
\xs ys -> return $ ValuePrim $ BoolValue $ xs == ys
def "!=" = Just $
fun2 $
\xs ys -> return $ ValuePrim $ BoolValue $ xs /= ys
-- The short-circuiting is handled directly in 'eval'; these cases
-- are only used when partially applying and such.
def "&&" = Just $
fun2 $ \x y ->
return $ ValuePrim $ BoolValue $ asBool x && asBool y
def "||" = Just $
fun2 $ \x y ->
return $ ValuePrim $ BoolValue $ asBool x || asBool y
def "<" =
Just $
bopDef $
sintCmp P.CmpSlt ++ uintCmp P.CmpUlt
++ floatCmp P.FCmpLt
++ boolCmp P.CmpLlt
def ">" =
Just $
bopDef $
flipCmps $
sintCmp P.CmpSlt ++ uintCmp P.CmpUlt
++ floatCmp P.FCmpLt
++ boolCmp P.CmpLlt
def "<=" =
Just $
bopDef $
sintCmp P.CmpSle ++ uintCmp P.CmpUle
++ floatCmp P.FCmpLe
++ boolCmp P.CmpLle
def ">=" =
Just $
bopDef $
flipCmps $
sintCmp P.CmpSle ++ uintCmp P.CmpUle
++ floatCmp P.FCmpLe
++ boolCmp P.CmpLle
def s
| Just bop <- find ((s ==) . pretty) P.allBinOps =
Just $ tbopDef $ P.doBinOp bop
| Just unop <- find ((s ==) . pretty) P.allCmpOps =
Just $ tbopDef $ \x y -> P.BoolValue <$> P.doCmpOp unop x y
| Just cop <- find ((s ==) . pretty) P.allConvOps =
Just $ unopDef [(getV, Just . putV, P.doConvOp cop)]
| Just unop <- find ((s ==) . pretty) P.allUnOps =
Just $ unopDef [(getV, Just . putV, P.doUnOp unop)]
| Just (pts, _, f) <- M.lookup s P.primFuns =
case length pts of
1 -> Just $ unopDef [(getV, Just . putV, f . pure)]
_ -> Just $
fun1 $ \x -> do
let getV' (ValuePrim v) = Just v
getV' _ = Nothing
case mapM getV' =<< fromTuple x of
Just vs
| Just res <- fmap putV . f =<< mapM getV vs -> do
breakOnNaN vs res
return $ ValuePrim res
_ ->
error $ "Cannot apply " ++ pretty s ++ " to " ++ pretty x
| "sign_" `isPrefixOf` s =
Just $
fun1 $ \x ->
case x of
(ValuePrim (UnsignedValue x')) ->
return $ ValuePrim $ SignedValue x'
_ -> error $ "Cannot sign: " ++ pretty x
| "unsign_" `isPrefixOf` s =
Just $
fun1 $ \x ->
case x of
(ValuePrim (SignedValue x')) ->
return $ ValuePrim $ UnsignedValue x'
_ -> error $ "Cannot unsign: " ++ pretty x
def s
| "map_stream" `isPrefixOf` s =
Just $ fun2t stream
def s | "reduce_stream" `isPrefixOf` s =
Just $ fun3t $ \_ f arg -> stream f arg
def "map" = Just $
TermPoly Nothing $ \t -> return $
ValueFun $ \v ->
case (fromTuple v, unfoldFunType t) of
(Just [f, xs], ([_], ret_t))
| Just rowshape <- typeRowShape ret_t ->
toArray' rowshape <$> mapM (apply noLoc mempty f) (snd $ fromArray xs)
| otherwise ->
error $ "Bad return type: " ++ pretty ret_t
_ ->
error $
"Invalid arguments to map intrinsic:\n"
++ unlines [pretty t, pretty v]
where
typeRowShape = sequenceA . structTypeShape mempty . stripArray 1
def s | "reduce" `isPrefixOf` s = Just $
fun3t $ \f ne xs ->
foldM (apply2 noLoc mempty f) ne $ snd $ fromArray xs
def "scan" = Just $
fun3t $ \f ne xs -> do
let next (out, acc) x = do
x' <- apply2 noLoc mempty f acc x
return (x' : out, x')
toArray' (valueShape ne) . reverse . fst
<$> foldM next ([], ne) (snd $ fromArray xs)
def "scatter" = Just $
fun3t $ \arr is vs ->
case arr of
ValueArray shape arr' ->
return $
ValueArray shape $
foldl' update arr' $
zip (map asInt $ snd $ fromArray is) (snd $ fromArray vs)
_ ->
error $ "scatter expects array, but got: " ++ pretty arr
where
update arr' (i, v) =
if i >= 0 && i < arrayLength arr'
then arr' // [(i, v)]
else arr'
def "hist" = Just $
fun6t $ \_ arr fun _ is vs ->
case arr of
ValueArray shape arr' ->
ValueArray shape
<$> foldM
(update fun)
arr'
(zip (map asInt $ snd $ fromArray is) (snd $ fromArray vs))
_ ->
error $ "hist expects array, but got: " ++ pretty arr
where
update fun arr' (i, v) =
if i >= 0 && i < arrayLength arr'
then do
v' <- apply2 noLoc mempty fun (arr' ! i) v
return $ arr' // [(i, v')]
else return arr'
def "partition" = Just $
fun3t $ \k f xs -> do
let (ShapeDim _ rowshape, xs') = fromArray xs
next outs x = do
i <- asInt <$> apply noLoc mempty f x
return $ insertAt i x outs
pack parts =
toTuple
[ toArray' rowshape $ concat parts,
toArray' rowshape $
map (ValuePrim . SignedValue . Int64Value . genericLength) parts
]
pack . map reverse
<$> foldM next (replicate (asInt k) []) xs'
where
insertAt 0 x (l : ls) = (x : l) : ls
insertAt i x (l : ls) = l : insertAt (i -1) x ls
insertAt _ _ ls = ls
def "unzip" = Just $
fun1 $ \x -> do
let ShapeDim _ (ShapeRecord fs) = valueShape x
Just [xs_shape, ys_shape] = areTupleFields fs
listPair (xs, ys) =
[toArray' xs_shape xs, toArray' ys_shape ys]
return $ toTuple $ listPair $ unzip $ map (fromPair . fromTuple) $ snd $ fromArray x
where
fromPair (Just [x, y]) = (x, y)
fromPair l = error $ "Not a pair: " ++ pretty l
def "zip" = Just $
fun2t $ \xs ys -> do
let ShapeDim _ xs_rowshape = valueShape xs
ShapeDim _ ys_rowshape = valueShape ys
return $
toArray' (ShapeRecord (tupleFields [xs_rowshape, ys_rowshape])) $
map toTuple $ transpose [snd $ fromArray xs, snd $ fromArray ys]
def "concat" = Just $
fun2t $ \xs ys -> do
let (ShapeDim _ rowshape, xs') = fromArray xs
(_, ys') = fromArray ys
return $ toArray' rowshape $ xs' ++ ys'
def "transpose" = Just $
fun1 $ \xs -> do
let (ShapeDim n (ShapeDim m shape), xs') = fromArray xs
return $
toArray (ShapeDim m (ShapeDim n shape)) $
map (toArray (ShapeDim n shape)) $ transpose $ map (snd . fromArray) xs'
def "rotate" = Just $
fun2t $ \i xs -> do
let (shape, xs') = fromArray xs
return $
if asInt i > 0
then
let (bef, aft) = splitAt (asInt i) xs'
in toArray shape $ aft ++ bef
else
let (bef, aft) = splitFromEnd (- asInt i) xs'
in toArray shape $ aft ++ bef
def "flatten" = Just $
fun1 $ \xs -> do
let (ShapeDim n (ShapeDim m shape), xs') = fromArray xs
return $ toArray (ShapeDim (n * m) shape) $ concatMap (snd . fromArray) xs'
def "unflatten" = Just $
fun3t $ \n m xs -> do
let (ShapeDim _ innershape, xs') = fromArray xs
rowshape = ShapeDim (asInt64 m) innershape
shape = ShapeDim (asInt64 n) rowshape
return $ toArray shape $ map (toArray rowshape) $ chunk (asInt m) xs'
def "opaque" = Just $ fun1 return
def "trace" = Just $ fun1 $ \v -> trace v >> return v
def "break" = Just $
fun1 $ \v -> do
break
return v
def s | nameFromString s `M.member` namesToPrimTypes = Nothing
def s = error $ "Missing intrinsic: " ++ s
tdef s = do
t <- nameFromString s `M.lookup` namesToPrimTypes
return $ T.TypeAbbr Unlifted [] $ Scalar $ Prim t
stream f arg@(ValueArray _ xs) =
let n = ValuePrim $ SignedValue $ Int64Value $ arrayLength xs
in apply2 noLoc mempty f n arg
stream _ arg = error $ "Cannot stream: " ++ pretty arg
interpretExp :: Ctx -> Exp -> F ExtOp Value
interpretExp ctx e = runEvalM (ctxImports ctx) $ eval (ctxEnv ctx) e
interpretDec :: Ctx -> Dec -> F ExtOp Ctx
interpretDec ctx d = do
env <- runEvalM (ctxImports ctx) $ evalDec (ctxEnv ctx) d
return ctx {ctxEnv = env}
interpretImport :: Ctx -> (FilePath, Prog) -> F ExtOp Ctx
interpretImport ctx (fp, prog) = do
env <- runEvalM (ctxImports ctx) $ foldM evalDec (ctxEnv ctx) $ progDecs prog
return ctx {ctxImports = M.insert fp env $ ctxImports ctx}
checkEntryArgs :: VName -> [F.Value] -> StructType -> Either String ()
checkEntryArgs entry args entry_t
| args_ts == param_ts =
return ()
| otherwise =
Left $
pretty $
expected
</> "Got input of types"
</> indent 2 (stack (map ppr args_ts))
where
(param_ts, _) = unfoldFunType entry_t
args_ts = map (valueStructType . valueType) args
expected
| null param_ts =
"Entry point " <> pquote (pprName entry) <> " is not a function."
| otherwise =
"Entry point " <> pquote (pprName entry) <> " expects input of type(s)"
</> indent 2 (stack (map ppr param_ts))
-- | Execute the named function on the given arguments; may fail
-- horribly if these are ill-typed.
interpretFunction :: Ctx -> VName -> [F.Value] -> Either String (F ExtOp Value)
interpretFunction ctx fname vs = do
ft <- case lookupVar (qualName fname) $ ctxEnv ctx of
Just (TermValue (Just (T.BoundV _ t)) _) ->
Right $ updateType (map valueType vs) t
Just (TermPoly (Just (T.BoundV _ t)) _) ->
Right $ updateType (map valueType vs) t
_ ->
Left $ "Unknown function `" <> prettyName fname <> "`."
vs' <- case mapM convertValue vs of
Just vs' -> Right vs'
Nothing -> Left "Invalid input: irregular array."
checkEntryArgs fname vs ft
Right $
runEvalM (ctxImports ctx) $ do
f <- evalTermVar (ctxEnv ctx) (qualName fname) ft
foldM (apply noLoc mempty) f vs'
where
updateType (vt : vts) (Scalar (Arrow als u _ rt)) =
Scalar $ Arrow als u (valueStructType vt) $ updateType vts rt
updateType _ t = t
convertValue (F.PrimValue p) = Just $ ValuePrim p
convertValue (F.ArrayValue arr t) = mkArray t =<< mapM convertValue (elems arr)