futhark-0.16.3: src/Futhark/Pass/ExplicitAllocations.hs
{-# LANGUAGE GeneralizedNewtypeDeriving #-}
{-# LANGUAGE TypeFamilies #-}
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE TupleSections #-}
{-# LANGUAGE ConstraintKinds #-}
{-# LANGUAGE UndecidableInstances #-}
{-# LANGUAGE DefaultSignatures #-}
-- | A generic transformation for adding memory allocations to a
-- Futhark program. Specialised by specific representations in
-- submodules.
module Futhark.Pass.ExplicitAllocations
( explicitAllocationsGeneric
, explicitAllocationsInStmsGeneric
, ExpHint(..)
, defaultExpHints
, Allocable
, Allocator(..)
, AllocM
, AllocEnv(..)
, SizeSubst(..)
, allocInStms
, allocForArray
, simplifiable
, arraySizeInBytesExp
, mkLetNamesB'
, mkLetNamesB''
-- * Module re-exports
--
-- These are highly likely to be needed by any downstream
-- users.
, module Control.Monad.Reader
, module Futhark.MonadFreshNames
, module Futhark.Pass
, module Futhark.Tools
)
where
import Control.Monad.State
import Control.Monad.Writer
import Control.Monad.Reader
import Control.Monad.RWS.Strict
import qualified Data.Map.Strict as M
import qualified Data.Set as S
import Data.Maybe
import Data.List (foldl', zip4, partition, sort)
import qualified Futhark.Analysis.UsageTable as UT
import Futhark.Optimise.Simplify.Lore (mkWiseBody)
import Futhark.MonadFreshNames
import Futhark.IR.Mem
import qualified Futhark.IR.Mem.IxFun as IxFun
import Futhark.Tools
import Futhark.Optimise.Simplify.Engine (SimpleOps (..))
import qualified Futhark.Optimise.Simplify.Engine as Engine
import Futhark.Pass
import Futhark.Util (splitFromEnd, takeLast)
data AllocStm = SizeComputation VName (PrimExp VName)
| Allocation VName SubExp Space
| ArrayCopy VName VName
deriving (Eq, Ord, Show)
bindAllocStm :: (MonadBinder m, Op (Lore m) ~ MemOp inner) =>
AllocStm -> m ()
bindAllocStm (SizeComputation name pe) =
letBindNames [name] =<< toExp (coerceIntPrimExp Int64 pe)
bindAllocStm (Allocation name size space) =
letBindNames [name] $ Op $ Alloc size space
bindAllocStm (ArrayCopy name src) =
letBindNames [name] $ BasicOp $ Copy src
class (MonadFreshNames m, HasScope lore m, Mem lore) =>
Allocator lore m where
addAllocStm :: AllocStm -> m ()
askDefaultSpace :: m Space
default addAllocStm :: (Allocable fromlore lore,
m ~ AllocM fromlore lore)
=> AllocStm -> m ()
addAllocStm (SizeComputation name se) =
letBindNames [name] =<< toExp (coerceIntPrimExp Int64 se)
addAllocStm (Allocation name size space) =
letBindNames [name] $ Op $ allocOp size space
addAllocStm (ArrayCopy name src) =
letBindNames [name] $ BasicOp $ Copy src
-- | The subexpression giving the number of elements we should
-- allocate space for. See 'ChunkMap' comment.
dimAllocationSize :: SubExp -> m SubExp
default dimAllocationSize :: m ~ AllocM fromlore lore
=> SubExp -> m SubExp
dimAllocationSize (Var v) =
-- It is important to recurse here, as the substitution may itself
-- be a chunk size.
maybe (return $ Var v) dimAllocationSize =<< asks (M.lookup v . chunkMap)
dimAllocationSize size =
return size
-- | Get those names that are known to be constants at run-time.
askConsts :: m (S.Set VName)
expHints :: Exp lore -> m [ExpHint]
expHints = defaultExpHints
allocateMemory :: Allocator lore m =>
String -> SubExp -> Space -> m VName
allocateMemory desc size space = do
v <- newVName desc
addAllocStm $ Allocation v size space
return v
computeSize :: Allocator lore m =>
String -> PrimExp VName -> m SubExp
computeSize desc se = do
v <- newVName desc
addAllocStm $ SizeComputation v se
return $ Var v
type Allocable fromlore tolore =
(PrettyLore fromlore, PrettyLore tolore,
Mem tolore,
FParamInfo fromlore ~ DeclType,
LParamInfo fromlore ~ Type,
BranchType fromlore ~ ExtType,
RetType fromlore ~ DeclExtType,
BodyDec fromlore ~ (),
BodyDec tolore ~ (),
ExpDec tolore ~ (),
SizeSubst (Op tolore),
BinderOps tolore)
-- | A mapping from chunk names to their maximum size. XXX FIXME
-- HACK: This is part of a hack to add loop-invariant allocations to
-- reduce kernels, because memory expansion does not use range
-- analysis yet (it should).
type ChunkMap = M.Map VName SubExp
data AllocEnv fromlore tolore =
AllocEnv { chunkMap :: ChunkMap
, aggressiveReuse :: Bool
-- ^ Aggressively try to reuse memory in do-loops -
-- should be True inside kernels, False outside.
, allocSpace :: Space
-- ^ When allocating memory, put it in this memory space.
-- This is primarily used to ensure that group-wide
-- statements store their results in local memory.
, envConsts :: S.Set VName
-- ^ The set of names that are known to be constants at
-- kernel compile time.
, allocInOp :: Op fromlore -> AllocM fromlore tolore (Op tolore)
, envExpHints :: Exp tolore -> AllocM fromlore tolore [ExpHint]
}
-- | Monad for adding allocations to an entire program.
newtype AllocM fromlore tolore a =
AllocM (BinderT tolore (ReaderT (AllocEnv fromlore tolore) (State VNameSource)) a)
deriving (Applicative, Functor, Monad,
MonadFreshNames,
HasScope tolore,
LocalScope tolore,
MonadReader (AllocEnv fromlore tolore))
instance (Allocable fromlore tolore, Allocator tolore (AllocM fromlore tolore)) =>
MonadBinder (AllocM fromlore tolore) where
type Lore (AllocM fromlore tolore) = tolore
mkExpDecM _ _ = return ()
mkLetNamesM names e = do
pat <- patternWithAllocations names e
return $ Let pat (defAux ()) e
mkBodyM bnds res = return $ Body () bnds res
addStms = AllocM . addStms
collectStms (AllocM m) = AllocM $ collectStms m
instance (Allocable fromlore tolore) =>
Allocator tolore (AllocM fromlore tolore) where
expHints e = do
f <- asks envExpHints
f e
askDefaultSpace = asks allocSpace
askConsts = asks envConsts
runAllocM :: MonadFreshNames m =>
(Op fromlore -> AllocM fromlore tolore (Op tolore))
-> (Exp tolore -> AllocM fromlore tolore [ExpHint])
-> AllocM fromlore tolore a -> m a
runAllocM handleOp hints (AllocM m) =
fmap fst $ modifyNameSource $ runState $ runReaderT (runBinderT m mempty) env
where env = AllocEnv { chunkMap = mempty
, aggressiveReuse = False
, allocSpace = DefaultSpace
, envConsts = mempty
, allocInOp = handleOp
, envExpHints = hints
}
-- | Monad for adding allocations to a single pattern.
newtype PatAllocM lore a = PatAllocM (RWS
(Scope lore)
[AllocStm]
VNameSource
a)
deriving (Applicative, Functor, Monad,
HasScope lore,
MonadWriter [AllocStm],
MonadFreshNames)
instance Mem lore => Allocator lore (PatAllocM lore) where
addAllocStm = tell . pure
dimAllocationSize = return
askDefaultSpace = return DefaultSpace
askConsts = pure mempty
runPatAllocM :: MonadFreshNames m =>
PatAllocM lore a -> Scope lore
-> m (a, [AllocStm])
runPatAllocM (PatAllocM m) mems =
modifyNameSource $ frob . runRWS m mems
where frob (a,s,w) = ((a,w),s)
arraySizeInBytesExp :: Type -> PrimExp VName
arraySizeInBytesExp t =
foldl' (*)
(ValueExp $ IntValue $ Int64Value $ primByteSize $ elemType t) $
map (sExt Int64 .primExpFromSubExp int32) (arrayDims t)
arraySizeInBytesExpM :: Allocator lore m => Type -> m (PrimExp VName)
arraySizeInBytesExpM t = do
dims <- mapM dimAllocationSize (arrayDims t)
let dim_prod_i32 = product $ map (sExt Int64 . primExpFromSubExp int32) dims
let elm_size_i64 = ValueExp $ IntValue $ Int64Value $ primByteSize $ elemType t
return $ product [ dim_prod_i32, elm_size_i64 ]
arraySizeInBytes :: Allocator lore m => Type -> m SubExp
arraySizeInBytes = computeSize "bytes" <=< arraySizeInBytesExpM
-- | Allocate memory for a value of the given type.
allocForArray :: Allocator lore m =>
Type -> Space -> m VName
allocForArray t space = do
size <- arraySizeInBytes t
allocateMemory "mem" size space
allocsForStm :: (Allocator lore m, ExpDec lore ~ ()) =>
[Ident] -> [Ident] -> Exp lore
-> m (Stm lore)
allocsForStm sizeidents validents e = do
rts <- expReturns e
hints <- expHints e
(ctxElems, valElems) <- allocsForPattern sizeidents validents rts hints
return $ Let (Pattern ctxElems valElems) (defAux ()) e
patternWithAllocations :: (Allocator lore m, ExpDec lore ~ ()) =>
[VName]
-> Exp lore
-> m (Pattern lore)
patternWithAllocations names e = do
(ts',sizes) <- instantiateShapes' =<< expExtType e
let identForBindage name t =
pure $ Ident name t
vals <- sequence [ identForBindage name t | (name, t) <- zip names ts' ]
stmPattern <$> allocsForStm sizes vals e
allocsForPattern :: Allocator lore m =>
[Ident] -> [Ident] -> [ExpReturns] -> [ExpHint]
-> m ([PatElem lore],
[PatElem lore])
allocsForPattern sizeidents validents rts hints = do
let sizes' = [ PatElem size $ MemPrim int32 | size <- map identName sizeidents ]
(vals, (exts, mems)) <-
runWriterT $ forM (zip3 validents rts hints) $ \(ident, rt, hint) -> do
let shape = arrayShape $ identType ident
case rt of
MemPrim _ -> do
summary <- lift $ summaryForBindage (identType ident) hint
return $ PatElem (identName ident) summary
MemMem space ->
return $ PatElem (identName ident) $
MemMem space
MemArray bt _ u (Just (ReturnsInBlock mem extixfun)) -> do
(patels, ixfn) <- instantiateExtIxFun ident extixfun
tell (patels, [])
return $ PatElem (identName ident) $
MemArray bt shape u $
ArrayIn mem ixfn
MemArray _ extshape _ Nothing
| Just _ <- knownShape extshape -> do
summary <- lift $ summaryForBindage (identType ident) hint
return $ PatElem (identName ident) summary
MemArray bt _ u (Just (ReturnsNewBlock space _ extixfn)) -> do
-- treat existential index function first
(patels, ixfn) <- instantiateExtIxFun ident extixfn
tell (patels, [])
memid <- lift $ mkMemIdent ident space
tell ([], [PatElem (identName memid) $ MemMem space])
return $ PatElem (identName ident) $ MemArray bt shape u $
ArrayIn (identName memid) ixfn
_ -> error "Impossible case reached in allocsForPattern!"
return (sizes' <> exts <> mems,
vals)
where knownShape = mapM known . shapeDims
known (Free v) = Just v
known Ext{} = Nothing
mkMemIdent :: (MonadFreshNames m) => Ident -> Space -> m Ident
mkMemIdent ident space = do
let memname = baseString (identName ident) <> "_mem"
newIdent memname $ Mem space
instantiateExtIxFun :: MonadFreshNames m =>
Ident -> ExtIxFun ->
m ([PatElemT (MemInfo d u ret)], IxFun)
instantiateExtIxFun idd ext_ixfn = do
let isAndPtps = S.toList $
foldMap onlyExts $
foldMap leafExpTypes ext_ixfn
-- Find the existentials that reuse the sizeidents, and
-- those that need new pattern elements. Assumes that the
-- Exts form a contiguous interval of integers.
let (size_exts, new_exts) =
span ((<length sizeidents) . fst) $ sort isAndPtps
(new_substs, patels) <-
fmap unzip $ forM new_exts $ \(i, t) -> do
v <- newVName $ baseString (identName idd) <> "_ixfn"
return ((Ext i, LeafExp (Free v) t),
PatElem v $ MemPrim t)
let size_substs = zipWith (\(i, t) ident ->
(Ext i, LeafExp (Free (identName ident)) t))
size_exts sizeidents
substs = M.fromList $ new_substs <> size_substs
ixfn <- instantiateIxFun $ IxFun.substituteInIxFun substs ext_ixfn
return (patels, ixfn)
onlyExts :: (Ext a, PrimType) -> S.Set (Int, PrimType)
onlyExts (Free _, _) = S.empty
onlyExts (Ext i, t) = S.singleton (i, t)
instantiateIxFun :: Monad m => ExtIxFun -> m IxFun
instantiateIxFun = traverse $ traverse inst
where inst Ext{} = error "instantiateIxFun: not yet"
inst (Free x) = return x
summaryForBindage :: Allocator lore m =>
Type -> ExpHint
-> m (MemBound NoUniqueness)
summaryForBindage (Prim bt) _ =
return $ MemPrim bt
summaryForBindage (Mem space) _ =
return $ MemMem space
summaryForBindage t@(Array bt shape u) NoHint = do
m <- allocForArray t =<< askDefaultSpace
return $ directIxFun bt shape u m t
summaryForBindage t (Hint ixfun space) = do
let bt = elemType t
bytes <- computeSize "bytes" $
product [product $ map (sExt Int64) $ IxFun.base ixfun,
fromIntegral (primByteSize (elemType t)::Int64)]
m <- allocateMemory "mem" bytes space
return $ MemArray bt (arrayShape t) NoUniqueness $ ArrayIn m ixfun
lookupMemSpace :: (HasScope lore m, Monad m) => VName -> m Space
lookupMemSpace v = do
t <- lookupType v
case t of
Mem space -> return space
_ -> error $ "lookupMemSpace: " ++ pretty v ++ " is not a memory block."
directIxFun :: PrimType -> Shape -> u -> VName -> Type -> MemBound u
directIxFun bt shape u mem t =
let ixf = IxFun.iota $ map (primExpFromSubExp int32) $ arrayDims t
in MemArray bt shape u $ ArrayIn mem ixf
allocInFParams :: (Allocable fromlore tolore) =>
[(FParam fromlore, Space)] ->
([FParam tolore] -> AllocM fromlore tolore a)
-> AllocM fromlore tolore a
allocInFParams params m = do
(valparams, (ctxparams, memparams)) <-
runWriterT $ mapM (uncurry allocInFParam) params
let params' = ctxparams <> memparams <> valparams
summary = scopeOfFParams params'
localScope summary $ m params'
allocInFParam :: (Allocable fromlore tolore) =>
FParam fromlore
-> Space
-> WriterT ([FParam tolore], [FParam tolore])
(AllocM fromlore tolore) (FParam tolore)
allocInFParam param pspace =
case paramDeclType param of
Array bt shape u -> do
let memname = baseString (paramName param) <> "_mem"
ixfun = IxFun.iota $ map (primExpFromSubExp int32) $ shapeDims shape
mem <- lift $ newVName memname
tell ([], [Param mem $ MemMem pspace])
return param { paramDec = MemArray bt shape u $ ArrayIn mem ixfun }
Prim bt ->
return param { paramDec = MemPrim bt }
Mem space ->
return param { paramDec = MemMem space }
allocInMergeParams :: (Allocable fromlore tolore,
Allocator tolore (AllocM fromlore tolore)) =>
[(FParam fromlore,SubExp)]
-> ([FParam tolore]
-> [FParam tolore]
-> ([SubExp] -> AllocM fromlore tolore ([SubExp], [SubExp]))
-> AllocM fromlore tolore a)
-> AllocM fromlore tolore a
allocInMergeParams merge m = do
((valparams, handle_loop_subexps), (ctx_params, mem_params)) <-
runWriterT $ unzip <$> mapM allocInMergeParam merge
let mergeparams' = ctx_params <> mem_params <> valparams
summary = scopeOfFParams mergeparams'
mk_loop_res ses = do
(valargs, (ctxargs, memargs)) <-
runWriterT $ zipWithM ($) handle_loop_subexps ses
return (ctxargs <> memargs, valargs)
localScope summary $ m (ctx_params <> mem_params) valparams mk_loop_res
where
allocInMergeParam :: (Allocable fromlore tolore, Allocator tolore (AllocM fromlore tolore)) =>
(Param DeclType, SubExp) ->
WriterT
([FParam tolore], [FParam tolore])
(AllocM fromlore tolore)
(FParam tolore, SubExp -> WriterT ([SubExp], [SubExp]) (AllocM fromlore tolore) SubExp)
allocInMergeParam (mergeparam, Var v)
| Array bt shape u <- paramDeclType mergeparam = do
(mem', _) <- lift $ lookupArraySummary v
mem_space <- lift $ lookupMemSpace mem'
(_, ext_ixfun, substs, _) <- lift $ existentializeArray mem_space v
(ctx_params, param_ixfun_substs) <-
unzip <$>
mapM (\primExp -> do
let pt = primExpType primExp
vname <- lift $ newVName "ctx_param_ext"
return (Param vname $ MemPrim pt,
fmap Free $ primExpFromSubExp int32 $ Var vname))
substs
tell (ctx_params, [])
param_ixfun <- instantiateIxFun $
IxFun.substituteInIxFun (M.fromList $ zip (fmap Ext [0..]) param_ixfun_substs)
ext_ixfun
mem_name <- newVName "mem_param"
tell ([], [Param mem_name $ MemMem mem_space])
return (mergeparam { paramDec = MemArray bt shape u $ ArrayIn mem_name param_ixfun },
ensureArrayIn mem_space)
allocInMergeParam (mergeparam, _) = doDefault mergeparam =<< lift askDefaultSpace
doDefault mergeparam space = do
mergeparam' <- allocInFParam mergeparam space
return (mergeparam', linearFuncallArg (paramType mergeparam) space)
-- Returns the existentialized index function, the list of substituted values and the memory location.
existentializeArray :: (Allocable fromlore tolore, Allocator tolore (AllocM fromlore tolore)) =>
Space -> VName -> AllocM fromlore tolore (SubExp, ExtIxFun, [PrimExp VName], VName)
existentializeArray space v = do
(mem', ixfun) <- lookupArraySummary v
sp <- lookupMemSpace mem'
let (ext_ixfun', substs') = runState (IxFun.existentialize ixfun) []
case (ext_ixfun', sp == space) of
(Just x, True) -> return (Var v, x, substs', mem')
_ -> do
(mem, subexp) <- allocLinearArray space (baseString v) v
ixfun' <- fromJust <$> subExpIxFun subexp
let (ext_ixfun, substs) = runState (IxFun.existentialize ixfun') []
return (subexp, fromJust ext_ixfun, substs, mem)
ensureArrayIn :: (Allocable fromlore tolore,
Allocator tolore (AllocM fromlore tolore)) =>
Space -> SubExp
-> WriterT ([SubExp], [SubExp]) (AllocM fromlore tolore) SubExp
ensureArrayIn _ (Constant v) =
error $ "ensureArrayIn: " ++ pretty v ++ " cannot be an array."
ensureArrayIn space (Var v) = do
(sub_exp, _, substs, mem) <- lift $ existentializeArray space v
(ctx_vals, _) <-
unzip <$>
mapM (\s -> do
vname <- lift $ letExp "ctx_val" =<< toExp s
return (Var vname, fmap Free $ primExpFromSubExp int32 $ Var vname))
substs
tell (ctx_vals, [Var mem])
return sub_exp
ensureDirectArray :: (Allocable fromlore tolore,
Allocator tolore (AllocM fromlore tolore)) =>
Maybe Space -> VName -> AllocM fromlore tolore (VName, SubExp)
ensureDirectArray space_ok v = do
(mem, ixfun) <- lookupArraySummary v
mem_space <- lookupMemSpace mem
default_space <- askDefaultSpace
if IxFun.isDirect ixfun && maybe True (==mem_space) space_ok
then return (mem, Var v)
else needCopy (fromMaybe default_space space_ok)
where needCopy space =
-- We need to do a new allocation, copy 'v', and make a new
-- binding for the size of the memory block.
allocLinearArray space (baseString v) v
allocLinearArray :: (Allocable fromlore tolore, Allocator tolore (AllocM fromlore tolore)) =>
Space -> String -> VName
-> AllocM fromlore tolore (VName, SubExp)
allocLinearArray space s v = do
t <- lookupType v
mem <- allocForArray t space
v' <- newIdent (s ++ "_linear") t
let ixfun = directIxFun (elemType t) (arrayShape t) NoUniqueness mem t
let pat = Pattern [] [PatElem (identName v') ixfun]
addStm $ Let pat (defAux ()) $ BasicOp $ Copy v
return (mem, Var $ identName v')
funcallArgs :: (Allocable fromlore tolore,
Allocator tolore (AllocM fromlore tolore)) =>
[(SubExp,Diet)] -> AllocM fromlore tolore [(SubExp,Diet)]
funcallArgs args = do
(valargs, (ctx_args, mem_and_size_args)) <- runWriterT $ forM args $ \(arg,d) -> do
t <- lift $ subExpType arg
space <- lift askDefaultSpace
arg' <- linearFuncallArg t space arg
return (arg', d)
return $ map (,Observe) (ctx_args <> mem_and_size_args) <> valargs
linearFuncallArg :: (Allocable fromlore tolore,
Allocator tolore (AllocM fromlore tolore)) =>
Type -> Space -> SubExp
-> WriterT ([SubExp], [SubExp]) (AllocM fromlore tolore) SubExp
linearFuncallArg Array{} space (Var v) = do
(mem, arg') <- lift $ ensureDirectArray (Just space) v
tell ([], [Var mem])
return arg'
linearFuncallArg _ _ arg =
return arg
explicitAllocationsGeneric :: (Allocable fromlore tolore,
Allocator tolore (AllocM fromlore tolore)) =>
(Op fromlore -> AllocM fromlore tolore (Op tolore))
-> (Exp tolore -> AllocM fromlore tolore [ExpHint])
-> Pass fromlore tolore
explicitAllocationsGeneric handleOp hints =
Pass "explicit allocations" "Transform program to explicit memory representation" $
intraproceduralTransformationWithConsts onStms allocInFun
where onStms stms = runAllocM handleOp hints $ allocInStms stms pure
allocInFun consts (FunDef entry attrs fname rettype params fbody) =
runAllocM handleOp hints $ inScopeOf consts $
allocInFParams (zip params $ repeat DefaultSpace) $ \params' -> do
fbody' <- insertStmsM $ allocInFunBody
(map (const $ Just DefaultSpace) rettype) fbody
return $ FunDef entry attrs fname (memoryInDeclExtType rettype) params' fbody'
explicitAllocationsInStmsGeneric :: (MonadFreshNames m, HasScope tolore m,
Allocable fromlore tolore) =>
(Op fromlore -> AllocM fromlore tolore (Op tolore))
-> (Exp tolore -> AllocM fromlore tolore [ExpHint])
-> Stms fromlore -> m (Stms tolore)
explicitAllocationsInStmsGeneric handleOp hints stms = do
scope <- askScope
runAllocM handleOp hints $ localScope scope $ allocInStms stms return
memoryInDeclExtType :: [DeclExtType] -> [FunReturns]
memoryInDeclExtType ts = evalState (mapM addMem ts) $ startOfFreeIDRange ts
where addMem (Prim t) = return $ MemPrim t
addMem Mem{} = error "memoryInDeclExtType: too much memory"
addMem (Array bt shape u) = do
i <- get <* modify (+1)
return $ MemArray bt shape u $ ReturnsNewBlock DefaultSpace i $
IxFun.iota $ map convert $ shapeDims shape
convert (Ext i) = LeafExp (Ext i) int32
convert (Free v) = Free <$> primExpFromSubExp int32 v
startOfFreeIDRange :: [TypeBase ExtShape u] -> Int
startOfFreeIDRange = S.size . shapeContext
bodyReturnMemCtx :: (Allocable fromlore tolore, Allocator tolore (AllocM fromlore tolore)) =>
SubExp -> AllocM fromlore tolore [SubExp]
bodyReturnMemCtx Constant{} =
return []
bodyReturnMemCtx (Var v) = do
info <- lookupMemInfo v
case info of
MemPrim{} -> return []
MemMem{} -> return [] -- should not happen
MemArray _ _ _ (ArrayIn mem _) -> return [Var mem]
allocInFunBody :: (Allocable fromlore tolore, Allocator tolore (AllocM fromlore tolore)) =>
[Maybe Space] -> Body fromlore -> AllocM fromlore tolore (Body tolore)
allocInFunBody space_oks (Body _ bnds res) =
allocInStms bnds $ \bnds' -> do
(res'', allocs) <- collectStms $ do
res' <- zipWithM ensureDirect space_oks' res
let (ctx_res, val_res) = splitFromEnd num_vals res'
mem_ctx_res <- concat <$> mapM bodyReturnMemCtx val_res
return $ ctx_res <> mem_ctx_res <> val_res
return $ Body () (bnds'<>allocs) res''
where num_vals = length space_oks
space_oks' = replicate (length res - num_vals) Nothing ++ space_oks
ensureDirect :: (Allocable fromlore tolore, Allocator tolore (AllocM fromlore tolore)) =>
Maybe Space -> SubExp -> AllocM fromlore tolore SubExp
ensureDirect _ se@Constant{} = return se
ensureDirect space_ok (Var v) = do
bt <- primType <$> lookupType v
if bt
then return $ Var v
else do (_, v') <- ensureDirectArray space_ok v
return v'
allocInStms :: (Allocable fromlore tolore) =>
Stms fromlore -> (Stms tolore -> AllocM fromlore tolore a)
-> AllocM fromlore tolore a
allocInStms origstms m = allocInStms' (stmsToList origstms) mempty
where allocInStms' [] stms' =
m stms'
allocInStms' (x:xs) stms' = do
allocstms <- allocInStm' x
localScope (scopeOf allocstms) $ do
let stms_substs = foldMap sizeSubst allocstms
stms_consts = foldMap stmConsts allocstms
f env = env { chunkMap = stms_substs <> chunkMap env
, envConsts = stms_consts <> envConsts env
}
local f $ allocInStms' xs (stms'<>allocstms)
allocInStm' stm =
collectStms_ $ auxing (stmAux stm) $ allocInStm stm
allocInStm :: (Allocable fromlore tolore, Allocator tolore (AllocM fromlore tolore)) =>
Stm fromlore -> AllocM fromlore tolore ()
allocInStm (Let (Pattern sizeElems valElems) _ e) = do
e' <- allocInExp e
let sizeidents = map patElemIdent sizeElems
validents = map patElemIdent valElems
bnd <- allocsForStm sizeidents validents e'
addStm bnd
allocInExp :: (Allocable fromlore tolore, Allocator tolore (AllocM fromlore tolore)) =>
Exp fromlore -> AllocM fromlore tolore (Exp tolore)
allocInExp (DoLoop ctx val form (Body () bodybnds bodyres)) =
allocInMergeParams ctx $ \_ ctxparams' _ ->
allocInMergeParams val $
\new_ctx_params valparams' mk_loop_val -> do
form' <- allocInLoopForm form
localScope (scopeOf form') $ do
(valinit_ctx, valinit') <- mk_loop_val valinit
body' <- insertStmsM $ allocInStms bodybnds $ \bodybnds' -> do
((val_ses,valres'),val_retbnds) <- collectStms $ mk_loop_val valres
return $ Body () (bodybnds'<>val_retbnds) (ctxres++val_ses++valres')
return $
DoLoop
(zip (ctxparams'++new_ctx_params) (ctxinit++valinit_ctx))
(zip valparams' valinit')
form' body'
where (_ctxparams, ctxinit) = unzip ctx
(_valparams, valinit) = unzip val
(ctxres, valres) = splitAt (length ctx) bodyres
allocInExp (Apply fname args rettype loc) = do
args' <- funcallArgs args
return $ Apply fname args' (memoryInDeclExtType rettype) loc
allocInExp (If cond tbranch0 fbranch0 (IfDec rets ifsort)) = do
let num_rets = length rets
-- switch to the explicit-mem rep, but do nothing about results
(tbranch, tm_ixfs) <- allocInIfBody num_rets tbranch0
(fbranch, fm_ixfs) <- allocInIfBody num_rets fbranch0
tspaces <- mkSpaceOks num_rets tbranch
fspaces <- mkSpaceOks num_rets fbranch
-- try to generalize (antiunify) the index functions of the then and else bodies
let sp_substs = zipWith generalize (zip tspaces tm_ixfs) (zip fspaces fm_ixfs)
(spaces, subs) = unzip sp_substs
tsubs = map (selectSub fst) subs
fsubs = map (selectSub snd) subs
(tbranch', trets) <- addResCtxInIfBody rets tbranch spaces tsubs
(fbranch', frets) <- addResCtxInIfBody rets fbranch spaces fsubs
if frets /= trets then error "In allocInExp, IF case: antiunification of then/else produce different ExtInFn!"
else do -- above is a sanity check; implementation continues on else branch
let res_then = bodyResult tbranch'
res_else = bodyResult fbranch'
size_ext = length res_then - length trets
(ind_ses0, r_then_else) =
partition (\(r_then, r_else, _) -> r_then == r_else) $
zip3 res_then res_else [0 .. size_ext - 1]
(r_then_ext, r_else_ext, _) = unzip3 r_then_else
ind_ses = zipWith (\(se, _, i) k -> (i-k, se)) ind_ses0
[0 .. length ind_ses0 - 1]
rets'' = foldl (\acc (i, se) -> fixExt i se acc) trets ind_ses
tbranch'' = tbranch' { bodyResult = r_then_ext ++ drop size_ext res_then }
fbranch'' = fbranch' { bodyResult = r_else_ext ++ drop size_ext res_else }
res_if_expr = If cond tbranch'' fbranch'' $ IfDec rets'' ifsort
return res_if_expr
where generalize :: (Maybe Space, Maybe IxFun) -> (Maybe Space, Maybe IxFun)
-> (Maybe Space, Maybe (ExtIxFun, [(PrimExp VName, PrimExp VName)]))
generalize (Just sp1, Just ixf1) (Just sp2, Just ixf2) =
if sp1 /= sp2 then (Just sp1, Nothing)
else case IxFun.leastGeneralGeneralization ixf1 ixf2 of
Just (ixf, m) -> (Just sp1, Just (ixf, m))
Nothing -> (Just sp1, Nothing)
generalize (mbsp1, _) _ = (mbsp1, Nothing)
selectSub :: ((a, a) -> a) -> Maybe (ExtIxFun, [(a, a)]) ->
Maybe (ExtIxFun, [a])
selectSub f (Just (ixfn, m)) = Just (ixfn, map f m)
selectSub _ Nothing = Nothing
-- | Just introduces the new representation (index functions); but
-- does not unify (e.g., does not ensures direct); implementation
-- extends `allocInBodyNoDirect`, but also return `MemBind`
allocInIfBody :: (Allocable fromlore tolore, Allocator tolore (AllocM fromlore tolore)) =>
Int -> Body fromlore -> AllocM fromlore tolore (Body tolore, [Maybe IxFun])
allocInIfBody num_vals (Body _ bnds res) =
allocInStms bnds $ \bnds' -> do
let (_, val_res) = splitFromEnd num_vals res
mem_ixfs <- mapM subExpIxFun val_res
return (Body () bnds' res, mem_ixfs)
allocInExp e = mapExpM alloc e
where alloc =
identityMapper { mapOnBody = error "Unhandled Body in ExplicitAllocations"
, mapOnRetType = error "Unhandled RetType in ExplicitAllocations"
, mapOnBranchType = error "Unhandled BranchType in ExplicitAllocations"
, mapOnFParam = error "Unhandled FParam in ExplicitAllocations"
, mapOnLParam = error "Unhandled LParam in ExplicitAllocations"
, mapOnOp = \op -> do handle <- asks allocInOp
handle op
}
subExpIxFun :: (Allocable fromlore tolore, Allocator tolore (AllocM fromlore tolore)) =>
SubExp -> AllocM fromlore tolore (Maybe IxFun)
subExpIxFun Constant{} = return Nothing
subExpIxFun (Var v) = do
info <- lookupMemInfo v
case info of
MemArray _ptp _shp _u (ArrayIn _ ixf) -> return $ Just ixf
_ -> return Nothing
addResCtxInIfBody :: (Allocable fromlore tolore, Allocator tolore (AllocM fromlore tolore)) =>
[ExtType] -> Body tolore -> [Maybe Space] ->
[Maybe (ExtIxFun, [PrimExp VName])] ->
AllocM fromlore tolore (Body tolore, [BodyReturns])
addResCtxInIfBody ifrets (Body _ bnds res) spaces substs = do
let num_vals = length ifrets
(ctx_res, val_res) = splitFromEnd num_vals res
((res', bodyrets'), all_body_stms) <- collectStms $ do
mapM_ addStm bnds
(val_res', ext_ses_res, mem_ctx_res, bodyrets, total_existentials) <-
foldM helper ([], [], [], [], length ctx_res) (zip4 ifrets val_res substs spaces)
return (ctx_res <> ext_ses_res <> mem_ctx_res <> val_res',
-- We need to adjust the ReturnsNewBlock existentials, because they
-- should always be numbered _after_ all other existentials in the
-- return values.
reverse $ fst $ foldl adjustNewBlockExistential ([], total_existentials) bodyrets)
body' <- mkBodyM all_body_stms res'
return (body', bodyrets')
where
helper (res_acc, ext_acc, ctx_acc, br_acc, k) (ifr, r, mbixfsub, sp) =
case mbixfsub of
Nothing -> do
-- does NOT generalize/antiunify; ensure direct
r' <- ensureDirect sp r
mem_ctx_r <- bodyReturnMemCtx r'
let body_ret = inspect ifr sp
return (res_acc ++ [r'],
ext_acc,
ctx_acc ++ mem_ctx_r,
br_acc ++ [body_ret],
k)
Just (ixfn, m) -> do -- generalizes
let i = length m
ext_ses <- mapM (toSubExp "ixfn_exist") m
mem_ctx_r <- bodyReturnMemCtx r
let sp' = fromMaybe DefaultSpace sp
ixfn' = fmap (adjustExtPE k) ixfn
exttp = case ifr of
Array pt shp' u ->
MemArray pt shp' u $
ReturnsNewBlock sp' 0 ixfn'
_ -> error "Impossible case reached in addResCtxInIfBody"
return (res_acc ++ [r],
ext_acc ++ ext_ses,
ctx_acc ++ mem_ctx_r,
br_acc ++ [exttp],
k + i)
adjustNewBlockExistential :: ([BodyReturns], Int) -> BodyReturns -> ([BodyReturns], Int)
adjustNewBlockExistential (acc, k) (MemArray pt shp u (ReturnsNewBlock space _ ixfun)) =
(MemArray pt shp u (ReturnsNewBlock space k ixfun) : acc, k + 1)
adjustNewBlockExistential (acc, k) x = (x : acc, k)
inspect (Array pt shape u) space =
let space' = fromMaybe DefaultSpace space
bodyret = MemArray pt shape u $ ReturnsNewBlock space' 0 $
IxFun.iota $ map convert $ shapeDims shape
in bodyret
inspect (Prim pt) _ = MemPrim pt
inspect (Mem space) _ = MemMem space
convert (Ext i) = LeafExp (Ext i) int32
convert (Free v) = Free <$> primExpFromSubExp int32 v
adjustExtV :: Int -> Ext VName -> Ext VName
adjustExtV _ (Free v) = Free v
adjustExtV k (Ext i) = Ext (k + i)
adjustExtPE :: Int -> PrimExp (Ext VName) -> PrimExp (Ext VName)
adjustExtPE k = fmap (adjustExtV k)
mkSpaceOks :: (Mem tolore, LocalScope tolore m) =>
Int -> Body tolore -> m [Maybe Space]
mkSpaceOks num_vals (Body _ stms res) =
inScopeOf stms $
mapM mkSpaceOK $ takeLast num_vals res
where mkSpaceOK (Var v) = do
v_info <- lookupMemInfo v
case v_info of MemArray _ _ _ (ArrayIn mem _) -> do
mem_info <- lookupMemInfo mem
case mem_info of MemMem space -> return $ Just space
_ -> return Nothing
_ -> return Nothing
mkSpaceOK _ = return Nothing
allocInLoopForm :: (Allocable fromlore tolore,
Allocator tolore (AllocM fromlore tolore)) =>
LoopForm fromlore -> AllocM fromlore tolore (LoopForm tolore)
allocInLoopForm (WhileLoop v) = return $ WhileLoop v
allocInLoopForm (ForLoop i it n loopvars) =
ForLoop i it n <$> mapM allocInLoopVar loopvars
where allocInLoopVar (p,a) = do
(mem, ixfun) <- lookupArraySummary a
case paramType p of
Array bt shape u -> do
dims <- map (primExpFromSubExp int32) . arrayDims <$> lookupType a
let ixfun' = IxFun.slice ixfun $
fullSliceNum dims [DimFix $ LeafExp i int32]
return (p { paramDec = MemArray bt shape u $ ArrayIn mem ixfun' }, a)
Prim bt ->
return (p { paramDec = MemPrim bt }, a)
Mem space ->
return (p { paramDec = MemMem space }, a)
class SizeSubst op where
opSizeSubst :: PatternT dec -> op -> ChunkMap
opIsConst :: op -> Bool
opIsConst = const False
instance SizeSubst () where
opSizeSubst _ _ = mempty
instance SizeSubst op => SizeSubst (MemOp op) where
opSizeSubst pat (Inner op) = opSizeSubst pat op
opSizeSubst _ _ = mempty
opIsConst (Inner op) = opIsConst op
opIsConst _ = False
sizeSubst :: SizeSubst (Op lore) => Stm lore -> ChunkMap
sizeSubst (Let pat _ (Op op)) = opSizeSubst pat op
sizeSubst _ = mempty
stmConsts :: SizeSubst (Op lore) => Stm lore -> S.Set VName
stmConsts (Let pat _ (Op op))
| opIsConst op = S.fromList $ patternNames pat
stmConsts _ = mempty
mkLetNamesB' :: (Op (Lore m) ~ MemOp inner,
MonadBinder m, ExpDec (Lore m) ~ (),
Allocator (Lore m) (PatAllocM (Lore m))) =>
ExpDec (Lore m) -> [VName] -> Exp (Lore m) -> m (Stm (Lore m))
mkLetNamesB' dec names e = do
scope <- askScope
pat <- bindPatternWithAllocations scope names e
return $ Let pat (defAux dec) e
mkLetNamesB'' :: (Op (Lore m) ~ MemOp inner, ExpDec lore ~ (),
HasScope (Engine.Wise lore) m, Allocator lore (PatAllocM lore),
MonadBinder m, Engine.CanBeWise (Op lore)) =>
[VName] -> Exp (Engine.Wise lore)
-> m (Stm (Engine.Wise lore))
mkLetNamesB'' names e = do
scope <- Engine.removeScopeWisdom <$> askScope
(pat, prestms) <- runPatAllocM (patternWithAllocations names $ Engine.removeExpWisdom e) scope
mapM_ bindAllocStm prestms
let pat' = Engine.addWisdomToPattern pat e
dec = Engine.mkWiseExpDec pat' () e
return $ Let pat' (defAux dec) e
simplifiable :: (Engine.SimplifiableLore lore,
ExpDec lore ~ (),
BodyDec lore ~ (),
Op lore ~ MemOp inner,
Allocator lore (PatAllocM lore)) =>
(Engine.OpWithWisdom inner -> UT.UsageTable)
-> (inner -> Engine.SimpleM lore (Engine.OpWithWisdom inner, Stms (Engine.Wise lore)))
-> SimpleOps lore
simplifiable innerUsage simplifyInnerOp =
SimpleOps mkExpDecS' mkBodyS' protectOp opUsage simplifyOp
where mkExpDecS' _ pat e =
return $ Engine.mkWiseExpDec pat () e
mkBodyS' _ bnds res = return $ mkWiseBody () bnds res
protectOp taken pat (Alloc size space) = Just $ do
tbody <- resultBodyM [size]
fbody <- resultBodyM [intConst Int64 0]
size' <- letSubExp "hoisted_alloc_size" $
If taken tbody fbody $ IfDec [MemPrim int64] IfFallback
letBind pat $ Op $ Alloc size' space
protectOp _ _ _ = Nothing
opUsage (Alloc (Var size) _) =
UT.sizeUsage size
opUsage (Alloc _ _) =
mempty
opUsage (Inner inner) =
innerUsage inner
simplifyOp (Alloc size space) =
(,) <$> (Alloc <$> Engine.simplify size <*> pure space) <*> pure mempty
simplifyOp (Inner k) = do (k', hoisted) <- simplifyInnerOp k
return (Inner k', hoisted)
bindPatternWithAllocations :: (MonadBinder m,
ExpDec lore ~ (),
Op (Lore m) ~ MemOp inner,
Allocator lore (PatAllocM lore)) =>
Scope lore -> [VName] -> Exp lore
-> m (Pattern lore)
bindPatternWithAllocations types names e = do
(pat,prebnds) <- runPatAllocM (patternWithAllocations names e) types
mapM_ bindAllocStm prebnds
return pat
data ExpHint = NoHint
| Hint IxFun Space
defaultExpHints :: (Monad m, ASTLore lore) => Exp lore -> m [ExpHint]
defaultExpHints e = return $ replicate (expExtTypeSize e) NoHint