module Futhark.CodeGen.ImpGen.Multicore.SegHist
  ( compileSegHist,
  )
where

import Control.Monad
import Data.List (zip4)
import Futhark.CodeGen.ImpCode.Multicore qualified as Imp
import Futhark.CodeGen.ImpGen
import Futhark.CodeGen.ImpGen.Multicore.Base
import Futhark.CodeGen.ImpGen.Multicore.SegRed (compileSegRed')
import Futhark.IR.MCMem
import Futhark.MonadFreshNames
import Futhark.Transform.Rename (renameLambda)
import Futhark.Util (chunks, splitFromEnd, takeLast)
import Futhark.Util.IntegralExp (rem)
import Prelude hiding (quot, rem)

compileSegHist ::
  Pat LetDecMem ->
  SegSpace ->
  [HistOp MCMem] ->
  KernelBody MCMem ->
  TV Int32 ->
  MulticoreGen Imp.MCCode
compileSegHist :: Pat LParamMem
-> SegSpace
-> [HistOp MCMem]
-> KernelBody MCMem
-> TV Int32
-> MulticoreGen (Code Multicore)
compileSegHist Pat LParamMem
pat SegSpace
space [HistOp MCMem]
histops KernelBody MCMem
kbody TV Int32
nsubtasks
  | [(VName, SubExp)
_] <- SegSpace -> [(VName, SubExp)]
unSegSpace SegSpace
space =
      Pat LParamMem
-> SegSpace
-> [HistOp MCMem]
-> KernelBody MCMem
-> TV Int32
-> MulticoreGen (Code Multicore)
nonsegmentedHist Pat LParamMem
pat SegSpace
space [HistOp MCMem]
histops KernelBody MCMem
kbody TV Int32
nsubtasks
  | Bool
otherwise =
      Pat LParamMem
-> SegSpace
-> [HistOp MCMem]
-> KernelBody MCMem
-> MulticoreGen (Code Multicore)
segmentedHist Pat LParamMem
pat SegSpace
space [HistOp MCMem]
histops KernelBody MCMem
kbody

-- | Split some list into chunks equal to the number of values
-- returned by each 'SegBinOp'
segHistOpChunks :: [HistOp rep] -> [a] -> [[a]]
segHistOpChunks :: forall {k} (rep :: k) a. [HistOp rep] -> [a] -> [[a]]
segHistOpChunks = forall a. [Int] -> [a] -> [[a]]
chunks forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a b. (a -> b) -> [a] -> [b]
map (forall (t :: * -> *) a. Foldable t => t a -> Int
length forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall {k} (rep :: k). HistOp rep -> [SubExp]
histNeutral)

histSize :: HistOp MCMem -> Imp.TExp Int64
histSize :: HistOp MCMem -> TExp Int64
histSize = forall (t :: * -> *) a. (Foldable t, Num a) => t a -> a
product forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a b. (a -> b) -> [a] -> [b]
map SubExp -> TExp Int64
pe64 forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall d. ShapeBase d -> [d]
shapeDims forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall {k} (rep :: k). HistOp rep -> ShapeBase SubExp
histShape

genHistOpParams :: HistOp MCMem -> MulticoreGen ()
genHistOpParams :: HistOp MCMem -> MulticoreGen ()
genHistOpParams HistOp MCMem
histops =
  forall {k} (rep :: k) inner r op.
Mem rep inner =>
Maybe (Exp rep) -> Scope rep -> ImpM rep r op ()
dScope forall a. Maybe a
Nothing forall a b. (a -> b) -> a -> b
$ forall {k} (rep :: k) dec.
(LParamInfo rep ~ dec) =>
[Param dec] -> Scope rep
scopeOfLParams forall a b. (a -> b) -> a -> b
$ forall {k} (rep :: k). Lambda rep -> [LParam rep]
lambdaParams forall a b. (a -> b) -> a -> b
$ forall {k} (rep :: k). HistOp rep -> Lambda rep
histOp HistOp MCMem
histops

renameHistop :: HistOp MCMem -> MulticoreGen (HistOp MCMem)
renameHistop :: HistOp MCMem -> MulticoreGen (HistOp MCMem)
renameHistop HistOp MCMem
histop = do
  let op :: Lambda MCMem
op = forall {k} (rep :: k). HistOp rep -> Lambda rep
histOp HistOp MCMem
histop
  Lambda MCMem
lambda' <- forall {k} (rep :: k) (m :: * -> *).
(Renameable rep, MonadFreshNames m) =>
Lambda rep -> m (Lambda rep)
renameLambda Lambda MCMem
op
  forall (f :: * -> *) a. Applicative f => a -> f a
pure HistOp MCMem
histop {histOp :: Lambda MCMem
histOp = Lambda MCMem
lambda'}

nonsegmentedHist ::
  Pat LetDecMem ->
  SegSpace ->
  [HistOp MCMem] ->
  KernelBody MCMem ->
  TV Int32 ->
  MulticoreGen Imp.MCCode
nonsegmentedHist :: Pat LParamMem
-> SegSpace
-> [HistOp MCMem]
-> KernelBody MCMem
-> TV Int32
-> MulticoreGen (Code Multicore)
nonsegmentedHist Pat LParamMem
pat SegSpace
space [HistOp MCMem]
histops KernelBody MCMem
kbody TV Int32
num_histos = do
  let ns :: [SubExp]
ns = forall a b. (a -> b) -> [a] -> [b]
map forall a b. (a, b) -> b
snd forall a b. (a -> b) -> a -> b
$ SegSpace -> [(VName, SubExp)]
unSegSpace SegSpace
space
      ns_64 :: [TExp Int64]
ns_64 = forall a b. (a -> b) -> [a] -> [b]
map SubExp -> TExp Int64
pe64 [SubExp]
ns
      num_histos' :: TExp Int32
num_histos' = forall {k} (t :: k). TV t -> TExp t
tvExp TV Int32
num_histos
      hist_width :: TExp Int64
hist_width = HistOp MCMem -> TExp Int64
histSize forall a b. (a -> b) -> a -> b
$ forall a. [a] -> a
head [HistOp MCMem]
histops
      use_subhistogram :: TPrimExp Bool VName
use_subhistogram = forall {k} (t :: k) v. IntExp t => TPrimExp t v -> TPrimExp Int64 v
sExt64 TExp Int32
num_histos' forall a. Num a => a -> a -> a
* TExp Int64
hist_width forall {k} (t :: k) v.
TPrimExp t v -> TPrimExp t v -> TPrimExp Bool v
.<=. forall (t :: * -> *) a. (Foldable t, Num a) => t a -> a
product [TExp Int64]
ns_64

  [HistOp MCMem]
histops' <- [HistOp MCMem] -> MulticoreGen [HistOp MCMem]
renameHistOpLambda [HistOp MCMem]
histops

  -- Only do something if there is actually input.
  forall {k} (rep :: k) r op.
ImpM rep r op () -> ImpM rep r op (Code op)
collect forall a b. (a -> b) -> a -> b
$
    forall {k} (rep :: k) r op.
TPrimExp Bool VName -> ImpM rep r op () -> ImpM rep r op ()
sUnless (forall (t :: * -> *) a. (Foldable t, Num a) => t a -> a
product [TExp Int64]
ns_64 forall {k} (t :: k) v.
TPrimExp t v -> TPrimExp t v -> TPrimExp Bool v
.==. TExp Int64
0) forall a b. (a -> b) -> a -> b
$ do
      forall {k} (rep :: k) r op.
TPrimExp Bool VName
-> ImpM rep r op () -> ImpM rep r op () -> ImpM rep r op ()
sIf
        TPrimExp Bool VName
use_subhistogram
        (Pat LParamMem
-> SegSpace
-> [HistOp MCMem]
-> TV Int32
-> KernelBody MCMem
-> MulticoreGen ()
subHistogram Pat LParamMem
pat SegSpace
space [HistOp MCMem]
histops TV Int32
num_histos KernelBody MCMem
kbody)
        (Pat LParamMem
-> SegSpace
-> [HistOp MCMem]
-> KernelBody MCMem
-> MulticoreGen ()
atomicHistogram Pat LParamMem
pat SegSpace
space [HistOp MCMem]
histops' KernelBody MCMem
kbody)

-- |
-- Atomic Histogram approach
-- The implementation has three sub-strategies depending on the
-- type of the operator
-- 1. If values are integral scalars, a direct-supported atomic update is used.
-- 2. If values are on one memory location, e.g. a float, then a
-- CAS operation is used to perform the update, where the float is
-- casted to an integral scalar.
-- 1. and 2. currently only works for 32-bit and 64-bit types,
-- but GCC has support for 8-, 16- and 128- bit types as well.
-- 3. Otherwise a locking based approach is used
onOpAtomic :: HistOp MCMem -> MulticoreGen ([VName] -> [Imp.TExp Int64] -> MulticoreGen ())
onOpAtomic :: HistOp MCMem
-> MulticoreGen ([VName] -> [TExp Int64] -> MulticoreGen ())
onOpAtomic HistOp MCMem
op = do
  AtomicBinOp
atomics <- HostEnv -> AtomicBinOp
hostAtomics forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> forall {k} (rep :: k) r op. ImpM rep r op r
askEnv
  let lambda :: Lambda MCMem
lambda = forall {k} (rep :: k). HistOp rep -> Lambda rep
histOp HistOp MCMem
op
      do_op :: AtomicUpdate MCMem ()
do_op = AtomicBinOp -> Lambda MCMem -> AtomicUpdate MCMem ()
atomicUpdateLocking AtomicBinOp
atomics Lambda MCMem
lambda
  case AtomicUpdate MCMem ()
do_op of
    AtomicPrim [VName] -> [TExp Int64] -> MulticoreGen ()
f -> forall (f :: * -> *) a. Applicative f => a -> f a
pure [VName] -> [TExp Int64] -> MulticoreGen ()
f
    AtomicCAS [VName] -> [TExp Int64] -> MulticoreGen ()
f -> forall (f :: * -> *) a. Applicative f => a -> f a
pure [VName] -> [TExp Int64] -> MulticoreGen ()
f
    AtomicLocking Locking -> [VName] -> [TExp Int64] -> MulticoreGen ()
f -> do
      -- Allocate a static array of locks
      -- as in the GPU backend
      let num_locks :: Int
num_locks = Int
100151 -- This number is taken from the GPU backend
          dims :: [TExp Int64]
dims = forall a b. (a -> b) -> [a] -> [b]
map SubExp -> TExp Int64
pe64 forall a b. (a -> b) -> a -> b
$ forall d. ShapeBase d -> [d]
shapeDims (forall {k} (rep :: k). HistOp rep -> ShapeBase SubExp
histOpShape HistOp MCMem
op forall a. Semigroup a => a -> a -> a
<> forall {k} (rep :: k). HistOp rep -> ShapeBase SubExp
histShape HistOp MCMem
op)
      VName
locks <-
        forall {k} (rep :: k) r op.
String -> Space -> PrimType -> ArrayContents -> ImpM rep r op VName
sStaticArray String
"hist_locks" Space
DefaultSpace PrimType
int32 forall a b. (a -> b) -> a -> b
$
          Int -> ArrayContents
Imp.ArrayZeros Int
num_locks
      let l' :: Locking
l' = VName
-> TExp Int32
-> TExp Int32
-> TExp Int32
-> ([TExp Int64] -> [TExp Int64])
-> Locking
Locking VName
locks TExp Int32
0 TExp Int32
1 TExp Int32
0 (forall (f :: * -> *) a. Applicative f => a -> f a
pure forall b c a. (b -> c) -> (a -> b) -> a -> c
. (forall e. IntegralExp e => e -> e -> e
`rem` forall a b. (Integral a, Num b) => a -> b
fromIntegral Int
num_locks) forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall num. IntegralExp num => [num] -> [num] -> num
flattenIndex [TExp Int64]
dims)
      forall (f :: * -> *) a. Applicative f => a -> f a
pure forall a b. (a -> b) -> a -> b
$ Locking -> [VName] -> [TExp Int64] -> MulticoreGen ()
f Locking
l'

atomicHistogram ::
  Pat LetDecMem ->
  SegSpace ->
  [HistOp MCMem] ->
  KernelBody MCMem ->
  MulticoreGen ()
atomicHistogram :: Pat LParamMem
-> SegSpace
-> [HistOp MCMem]
-> KernelBody MCMem
-> MulticoreGen ()
atomicHistogram Pat LParamMem
pat SegSpace
space [HistOp MCMem]
histops KernelBody MCMem
kbody = do
  let ([VName]
is, [SubExp]
ns) = forall a b. [(a, b)] -> ([a], [b])
unzip forall a b. (a -> b) -> a -> b
$ SegSpace -> [(VName, SubExp)]
unSegSpace SegSpace
space
      ns_64 :: [TExp Int64]
ns_64 = forall a b. (a -> b) -> [a] -> [b]
map SubExp -> TExp Int64
pe64 [SubExp]
ns
  let num_red_res :: Int
num_red_res = forall (t :: * -> *) a. Foldable t => t a -> Int
length [HistOp MCMem]
histops forall a. Num a => a -> a -> a
+ forall (t :: * -> *) a. (Foldable t, Num a) => t a -> a
sum (forall a b. (a -> b) -> [a] -> [b]
map (forall (t :: * -> *) a. Foldable t => t a -> Int
length forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall {k} (rep :: k). HistOp rep -> [SubExp]
histNeutral) [HistOp MCMem]
histops)
      ([PatElem LParamMem]
all_red_pes, [PatElem LParamMem]
map_pes) = forall a. Int -> [a] -> ([a], [a])
splitAt Int
num_red_res forall a b. (a -> b) -> a -> b
$ forall dec. Pat dec -> [PatElem dec]
patElems Pat LParamMem
pat

  [[VName] -> [TExp Int64] -> MulticoreGen ()]
atomicOps <- forall (t :: * -> *) (m :: * -> *) a b.
(Traversable t, Monad m) =>
(a -> m b) -> t a -> m (t b)
mapM HistOp MCMem
-> MulticoreGen ([VName] -> [TExp Int64] -> MulticoreGen ())
onOpAtomic [HistOp MCMem]
histops

  Code Multicore
body <- forall {k} (rep :: k) r op.
ImpM rep r op () -> ImpM rep r op (Code op)
collect forall a b. (a -> b) -> a -> b
$ do
    forall {k} (rep :: k) r op. VName -> PrimType -> ImpM rep r op ()
dPrim_ (SegSpace -> VName
segFlat SegSpace
space) PrimType
int64
    forall {k} op (rep :: k) r. op -> ImpM rep r op ()
sOp forall a b. (a -> b) -> a -> b
$ VName -> Multicore
Imp.GetTaskId (SegSpace -> VName
segFlat SegSpace
space)
    String
-> ChunkLoopVectorization
-> (TExp Int64 -> MulticoreGen ())
-> MulticoreGen ()
generateChunkLoop String
"SegHist" ChunkLoopVectorization
Scalar forall a b. (a -> b) -> a -> b
$ \TExp Int64
flat_idx -> do
      forall (m :: * -> *) a b c.
Applicative m =>
(a -> b -> m c) -> [a] -> [b] -> m ()
zipWithM_ forall {k1} {k2} (t :: k1) (rep :: k2) r op.
VName -> TExp t -> ImpM rep r op ()
dPrimV_ [VName]
is forall a b. (a -> b) -> a -> b
$ forall num. IntegralExp num => [num] -> num -> [num]
unflattenIndex [TExp Int64]
ns_64 TExp Int64
flat_idx
      forall {k} (rep :: k) r op.
Names -> Stms rep -> ImpM rep r op () -> ImpM rep r op ()
compileStms forall a. Monoid a => a
mempty (forall {k} (rep :: k). KernelBody rep -> Stms rep
kernelBodyStms KernelBody MCMem
kbody) forall a b. (a -> b) -> a -> b
$ do
        let ([KernelResult]
red_res, [KernelResult]
map_res) =
              forall a. Int -> [a] -> ([a], [a])
splitFromEnd (forall (t :: * -> *) a. Foldable t => t a -> Int
length [PatElem LParamMem]
map_pes) forall a b. (a -> b) -> a -> b
$ forall {k} (rep :: k). KernelBody rep -> [KernelResult]
kernelBodyResult KernelBody MCMem
kbody
            red_res_split :: [([SubExp], [SubExp])]
red_res_split = forall {k} (rep :: k).
[HistOp rep] -> [SubExp] -> [([SubExp], [SubExp])]
splitHistResults [HistOp MCMem]
histops forall a b. (a -> b) -> a -> b
$ forall a b. (a -> b) -> [a] -> [b]
map KernelResult -> SubExp
kernelResultSubExp [KernelResult]
red_res

        let pes_per_op :: [[PatElem LParamMem]]
pes_per_op = forall a. [Int] -> [a] -> [[a]]
chunks (forall a b. (a -> b) -> [a] -> [b]
map (forall (t :: * -> *) a. Foldable t => t a -> Int
length forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall {k} (rep :: k). HistOp rep -> [VName]
histDest) [HistOp MCMem]
histops) [PatElem LParamMem]
all_red_pes
        forall (t :: * -> *) (m :: * -> *) a b.
(Foldable t, Monad m) =>
t a -> (a -> m b) -> m ()
forM_ (forall a b c d. [a] -> [b] -> [c] -> [d] -> [(a, b, c, d)]
zip4 [HistOp MCMem]
histops [([SubExp], [SubExp])]
red_res_split [[VName] -> [TExp Int64] -> MulticoreGen ()]
atomicOps [[PatElem LParamMem]]
pes_per_op) forall a b. (a -> b) -> a -> b
$
          \(HistOp ShapeBase SubExp
dest_shape SubExp
_ [VName]
_ [SubExp]
_ ShapeBase SubExp
shape Lambda MCMem
lam, ([SubExp]
bucket, [SubExp]
vs'), [VName] -> [TExp Int64] -> MulticoreGen ()
do_op, [PatElem LParamMem]
dest_res) -> do
            let ([Param LParamMem]
_is_params, [Param LParamMem]
vs_params) = forall a. Int -> [a] -> ([a], [a])
splitAt (forall (t :: * -> *) a. Foldable t => t a -> Int
length [SubExp]
vs') forall a b. (a -> b) -> a -> b
$ forall {k} (rep :: k). Lambda rep -> [LParam rep]
lambdaParams Lambda MCMem
lam
                dest_shape' :: [TExp Int64]
dest_shape' = forall a b. (a -> b) -> [a] -> [b]
map SubExp -> TExp Int64
pe64 forall a b. (a -> b) -> a -> b
$ forall d. ShapeBase d -> [d]
shapeDims ShapeBase SubExp
dest_shape
                bucket' :: [TExp Int64]
bucket' = forall a b. (a -> b) -> [a] -> [b]
map SubExp -> TExp Int64
pe64 [SubExp]
bucket
                bucket_in_bounds :: TPrimExp Bool VName
bucket_in_bounds = Slice (TExp Int64) -> [TExp Int64] -> TPrimExp Bool VName
inBounds (forall d. [DimIndex d] -> Slice d
Slice (forall a b. (a -> b) -> [a] -> [b]
map forall d. d -> DimIndex d
DimFix [TExp Int64]
bucket')) [TExp Int64]
dest_shape'

            forall {k} (rep :: k) r op.
Text -> ImpM rep r op () -> ImpM rep r op ()
sComment Text
"save map-out results" forall a b. (a -> b) -> a -> b
$
              forall (t :: * -> *) (m :: * -> *) a b.
(Foldable t, Monad m) =>
t a -> (a -> m b) -> m ()
forM_ (forall a b. [a] -> [b] -> [(a, b)]
zip [PatElem LParamMem]
map_pes [KernelResult]
map_res) forall a b. (a -> b) -> a -> b
$ \(PatElem LParamMem
pe, KernelResult
res) ->
                forall {k} (rep :: k) r op.
VName -> [TExp Int64] -> SubExp -> [TExp Int64] -> ImpM rep r op ()
copyDWIMFix (forall dec. PatElem dec -> VName
patElemName PatElem LParamMem
pe) (forall a b. (a -> b) -> [a] -> [b]
map forall a. a -> TPrimExp Int64 a
Imp.le64 [VName]
is) (KernelResult -> SubExp
kernelResultSubExp KernelResult
res) []

            forall {k} (rep :: k) r op.
Text -> ImpM rep r op () -> ImpM rep r op ()
sComment Text
"perform updates" forall a b. (a -> b) -> a -> b
$
              forall {k} (rep :: k) r op.
TPrimExp Bool VName -> ImpM rep r op () -> ImpM rep r op ()
sWhen TPrimExp Bool VName
bucket_in_bounds forall a b. (a -> b) -> a -> b
$ do
                let bucket_is :: [TExp Int64]
bucket_is = forall a b. (a -> b) -> [a] -> [b]
map forall a. a -> TPrimExp Int64 a
Imp.le64 (forall a. [a] -> [a]
init [VName]
is) forall a. [a] -> [a] -> [a]
++ [TExp Int64]
bucket'
                forall {k} (rep :: k) inner r op.
Mem rep inner =>
[LParam rep] -> ImpM rep r op ()
dLParams forall a b. (a -> b) -> a -> b
$ forall {k} (rep :: k). Lambda rep -> [LParam rep]
lambdaParams Lambda MCMem
lam
                forall {k} (rep :: k) r op.
ShapeBase SubExp
-> ([TExp Int64] -> ImpM rep r op ()) -> ImpM rep r op ()
sLoopNest ShapeBase SubExp
shape forall a b. (a -> b) -> a -> b
$ \[TExp Int64]
is' -> do
                  forall (t :: * -> *) (m :: * -> *) a b.
(Foldable t, Monad m) =>
t a -> (a -> m b) -> m ()
forM_ (forall a b. [a] -> [b] -> [(a, b)]
zip [Param LParamMem]
vs_params [SubExp]
vs') forall a b. (a -> b) -> a -> b
$ \(Param LParamMem
p, SubExp
res) ->
                    forall {k} (rep :: k) r op.
VName -> [TExp Int64] -> SubExp -> [TExp Int64] -> ImpM rep r op ()
copyDWIMFix (forall dec. Param dec -> VName
paramName Param LParamMem
p) [] SubExp
res [TExp Int64]
is'
                  [VName] -> [TExp Int64] -> MulticoreGen ()
do_op (forall a b. (a -> b) -> [a] -> [b]
map forall dec. PatElem dec -> VName
patElemName [PatElem LParamMem]
dest_res) ([TExp Int64]
bucket_is forall a. [a] -> [a] -> [a]
++ [TExp Int64]
is')

  [Param]
free_params <- forall a. FreeIn a => a -> MulticoreGen [Param]
freeParams Code Multicore
body
  forall {k} op (rep :: k) r. Code op -> ImpM rep r op ()
emit forall a b. (a -> b) -> a -> b
$ forall a. a -> Code a
Imp.Op forall a b. (a -> b) -> a -> b
$ String -> Code Multicore -> [Param] -> Multicore
Imp.ParLoop String
"atomic_seg_hist" Code Multicore
body [Param]
free_params

updateHisto ::
  HistOp MCMem ->
  [VName] ->
  [Imp.TExp Int64] ->
  Imp.TExp Int64 ->
  [Param LParamMem] ->
  MulticoreGen ()
updateHisto :: HistOp MCMem
-> [VName]
-> [TExp Int64]
-> TExp Int64
-> [Param LParamMem]
-> MulticoreGen ()
updateHisto HistOp MCMem
op [VName]
arrs [TExp Int64]
bucket TExp Int64
j [Param LParamMem]
uni_acc = do
  let bind_acc_params :: ImpM rep r op ()
bind_acc_params =
        forall (t :: * -> *) (m :: * -> *) a b.
(Foldable t, Monad m) =>
t a -> (a -> m b) -> m ()
forM_ (forall a b. [a] -> [b] -> [(a, b)]
zip [Param LParamMem]
uni_acc [VName]
arrs) forall a b. (a -> b) -> a -> b
$ \(Param LParamMem
acc_u, VName
arr) -> do
          forall {k} (rep :: k) r op.
VName -> [TExp Int64] -> SubExp -> [TExp Int64] -> ImpM rep r op ()
copyDWIMFix (forall dec. Param dec -> VName
paramName Param LParamMem
acc_u) [] (VName -> SubExp
Var VName
arr) [TExp Int64]
bucket

      op_body :: ImpM MCMem r op ()
op_body = forall {k} dec (rep :: k) r op.
[Param dec] -> Body rep -> ImpM rep r op ()
compileBody' [] forall a b. (a -> b) -> a -> b
$ forall {k} (rep :: k). Lambda rep -> Body rep
lambdaBody forall a b. (a -> b) -> a -> b
$ forall {k} (rep :: k). HistOp rep -> Lambda rep
histOp HistOp MCMem
op
      writeArray :: VName -> SubExp -> MulticoreGen ()
writeArray VName
arr SubExp
val = TExp Int64 -> MulticoreGen (Code Multicore) -> MulticoreGen ()
extractVectorLane TExp Int64
j forall a b. (a -> b) -> a -> b
$ forall {k} (rep :: k) r op.
ImpM rep r op () -> ImpM rep r op (Code op)
collect forall a b. (a -> b) -> a -> b
$ forall {k} (rep :: k) r op.
VName -> [TExp Int64] -> SubExp -> [TExp Int64] -> ImpM rep r op ()
copyDWIMFix VName
arr [TExp Int64]
bucket SubExp
val []
      do_hist :: MulticoreGen ()
do_hist = forall (m :: * -> *) a b c.
Applicative m =>
(a -> b -> m c) -> [a] -> [b] -> m ()
zipWithM_ VName -> SubExp -> MulticoreGen ()
writeArray [VName]
arrs forall a b. (a -> b) -> a -> b
$ forall a b. (a -> b) -> [a] -> [b]
map SubExpRes -> SubExp
resSubExp forall a b. (a -> b) -> a -> b
$ forall {k} (rep :: k). Body rep -> Result
bodyResult forall a b. (a -> b) -> a -> b
$ forall {k} (rep :: k). Lambda rep -> Body rep
lambdaBody forall a b. (a -> b) -> a -> b
$ forall {k} (rep :: k). HistOp rep -> Lambda rep
histOp HistOp MCMem
op

  forall {k} (rep :: k) r op.
Text -> ImpM rep r op () -> ImpM rep r op ()
sComment Text
"Start of body" forall a b. (a -> b) -> a -> b
$ do
    forall {k} {rep :: k} {r} {op}. ImpM rep r op ()
bind_acc_params
    forall {r} {op}. ImpM MCMem r op ()
op_body
    MulticoreGen ()
do_hist

-- Generates num_histos sub-histograms of the size
-- of the destination histogram
-- Then for each chunk of the input each subhistogram
-- is computed and finally combined through a segmented reduction
-- across the histogram indicies.
-- This is expected to be fast if len(histDest) is small
subHistogram ::
  Pat LetDecMem ->
  SegSpace ->
  [HistOp MCMem] ->
  TV Int32 ->
  KernelBody MCMem ->
  MulticoreGen ()
subHistogram :: Pat LParamMem
-> SegSpace
-> [HistOp MCMem]
-> TV Int32
-> KernelBody MCMem
-> MulticoreGen ()
subHistogram Pat LParamMem
pat SegSpace
space [HistOp MCMem]
histops TV Int32
num_histos KernelBody MCMem
kbody = do
  forall {k} op (rep :: k) r. Code op -> ImpM rep r op ()
emit forall a b. (a -> b) -> a -> b
$ forall a. String -> Maybe Exp -> Code a
Imp.DebugPrint String
"subHistogram segHist" forall a. Maybe a
Nothing

  let ([VName]
is, [SubExp]
ns) = forall a b. [(a, b)] -> ([a], [b])
unzip forall a b. (a -> b) -> a -> b
$ SegSpace -> [(VName, SubExp)]
unSegSpace SegSpace
space
      ns_64 :: [TExp Int64]
ns_64 = forall a b. (a -> b) -> [a] -> [b]
map SubExp -> TExp Int64
pe64 [SubExp]
ns

  let pes :: [PatElem LParamMem]
pes = forall dec. Pat dec -> [PatElem dec]
patElems Pat LParamMem
pat
      num_red_res :: Int
num_red_res = forall (t :: * -> *) a. Foldable t => t a -> Int
length [HistOp MCMem]
histops forall a. Num a => a -> a -> a
+ forall (t :: * -> *) a. (Foldable t, Num a) => t a -> a
sum (forall a b. (a -> b) -> [a] -> [b]
map (forall (t :: * -> *) a. Foldable t => t a -> Int
length forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall {k} (rep :: k). HistOp rep -> [SubExp]
histNeutral) [HistOp MCMem]
histops)
      map_pes :: [PatElem LParamMem]
map_pes = forall a. Int -> [a] -> [a]
drop Int
num_red_res [PatElem LParamMem]
pes
      per_red_pes :: [[PatElem LParamMem]]
per_red_pes = forall {k} (rep :: k) a. [HistOp rep] -> [a] -> [[a]]
segHistOpChunks [HistOp MCMem]
histops forall a b. (a -> b) -> a -> b
$ forall dec. Pat dec -> [PatElem dec]
patElems Pat LParamMem
pat

  -- Allocate array of subhistograms in the calling thread.  Each
  -- tasks will work in its own private allocations (to avoid false
  -- sharing), but this is where they will ultimately copy their
  -- results.
  [[VName]]
global_subhistograms <- forall (t :: * -> *) (m :: * -> *) a b.
(Traversable t, Monad m) =>
t a -> (a -> m b) -> m (t b)
forM [HistOp MCMem]
histops forall a b. (a -> b) -> a -> b
$ \HistOp MCMem
histop ->
    forall (t :: * -> *) (m :: * -> *) a b.
(Traversable t, Monad m) =>
t a -> (a -> m b) -> m (t b)
forM (forall {k} (rep :: k). HistOp rep -> [Type]
histType HistOp MCMem
histop) forall a b. (a -> b) -> a -> b
$ \Type
t -> do
      let shape :: ShapeBase SubExp
shape = forall d. [d] -> ShapeBase d
Shape [forall {k} (t :: k). TV t -> SubExp
tvSize TV Int32
num_histos] forall a. Semigroup a => a -> a -> a
<> forall shape u. ArrayShape shape => TypeBase shape u -> shape
arrayShape Type
t
      forall {k} (rep :: k) r op.
String
-> PrimType -> ShapeBase SubExp -> Space -> ImpM rep r op VName
sAllocArray String
"subhistogram" (forall shape u. TypeBase shape u -> PrimType
elemType Type
t) ShapeBase SubExp
shape Space
DefaultSpace

  let tid' :: TExp Int64
tid' = forall a. a -> TPrimExp Int64 a
Imp.le64 forall a b. (a -> b) -> a -> b
$ SegSpace -> VName
segFlat SegSpace
space

  -- Generate loop body of parallel function
  Code Multicore
body <- forall {k} (rep :: k) r op.
ImpM rep r op () -> ImpM rep r op (Code op)
collect forall a b. (a -> b) -> a -> b
$ do
    forall {k} (rep :: k) r op. VName -> PrimType -> ImpM rep r op ()
dPrim_ (SegSpace -> VName
segFlat SegSpace
space) PrimType
int64
    forall {k} op (rep :: k) r. op -> ImpM rep r op ()
sOp forall a b. (a -> b) -> a -> b
$ VName -> Multicore
Imp.GetTaskId (SegSpace -> VName
segFlat SegSpace
space)

    [[VName]]
local_subhistograms <- forall (t :: * -> *) (m :: * -> *) a b.
(Traversable t, Monad m) =>
t a -> (a -> m b) -> m (t b)
forM (forall a b. [a] -> [b] -> [(a, b)]
zip [[PatElem LParamMem]]
per_red_pes [HistOp MCMem]
histops) forall a b. (a -> b) -> a -> b
$ \([PatElem LParamMem]
pes', HistOp MCMem
histop) -> do
      [VName]
op_local_subhistograms <- forall (t :: * -> *) (m :: * -> *) a b.
(Traversable t, Monad m) =>
t a -> (a -> m b) -> m (t b)
forM (forall {k} (rep :: k). HistOp rep -> [Type]
histType HistOp MCMem
histop) forall a b. (a -> b) -> a -> b
$ \Type
t ->
        forall {k} (rep :: k) r op.
String
-> PrimType -> ShapeBase SubExp -> Space -> ImpM rep r op VName
sAllocArray String
"subhistogram" (forall shape u. TypeBase shape u -> PrimType
elemType Type
t) (forall shape u. ArrayShape shape => TypeBase shape u -> shape
arrayShape Type
t) Space
DefaultSpace

      forall (t :: * -> *) (m :: * -> *) a b.
(Foldable t, Monad m) =>
t a -> (a -> m b) -> m ()
forM_ (forall a b c. [a] -> [b] -> [c] -> [(a, b, c)]
zip3 [PatElem LParamMem]
pes' [VName]
op_local_subhistograms (forall {k} (rep :: k). HistOp rep -> [SubExp]
histNeutral HistOp MCMem
histop)) forall a b. (a -> b) -> a -> b
$ \(PatElem LParamMem
pe, VName
hist, SubExp
ne) ->
        -- First thread initializes histogram with dest vals. Others
        -- initialize with neutral element
        forall {k} (rep :: k) r op.
TPrimExp Bool VName
-> ImpM rep r op () -> ImpM rep r op () -> ImpM rep r op ()
sIf
          (TExp Int64
tid' forall {k} (t :: k) v.
TPrimExp t v -> TPrimExp t v -> TPrimExp Bool v
.==. TExp Int64
0)
          (forall {k} (rep :: k) r op.
VName -> [TExp Int64] -> SubExp -> [TExp Int64] -> ImpM rep r op ()
copyDWIMFix VName
hist [] (VName -> SubExp
Var forall a b. (a -> b) -> a -> b
$ forall dec. PatElem dec -> VName
patElemName PatElem LParamMem
pe) [])
          ( forall {k} (rep :: k) r op.
ShapeBase SubExp
-> ([TExp Int64] -> ImpM rep r op ()) -> ImpM rep r op ()
sLoopNest (forall {k} (rep :: k). HistOp rep -> ShapeBase SubExp
histShape HistOp MCMem
histop) forall a b. (a -> b) -> a -> b
$ \[TExp Int64]
shape_is ->
              forall {k} (rep :: k) r op.
ShapeBase SubExp
-> ([TExp Int64] -> ImpM rep r op ()) -> ImpM rep r op ()
sLoopNest (forall {k} (rep :: k). HistOp rep -> ShapeBase SubExp
histOpShape HistOp MCMem
histop) forall a b. (a -> b) -> a -> b
$ \[TExp Int64]
vec_is ->
                forall {k} (rep :: k) r op.
VName -> [TExp Int64] -> SubExp -> [TExp Int64] -> ImpM rep r op ()
copyDWIMFix VName
hist ([TExp Int64]
shape_is forall a. Semigroup a => a -> a -> a
<> [TExp Int64]
vec_is) SubExp
ne []
          )

      forall (f :: * -> *) a. Applicative f => a -> f a
pure [VName]
op_local_subhistograms

    MulticoreGen () -> MulticoreGen ()
inISPC forall a b. (a -> b) -> a -> b
$
      String
-> ChunkLoopVectorization
-> (TExp Int64 -> MulticoreGen ())
-> MulticoreGen ()
generateChunkLoop String
"SegRed" ChunkLoopVectorization
Vectorized forall a b. (a -> b) -> a -> b
$ \TExp Int64
i -> do
        forall (m :: * -> *) a b c.
Applicative m =>
(a -> b -> m c) -> [a] -> [b] -> m ()
zipWithM_ forall {k1} {k2} (t :: k1) (rep :: k2) r op.
VName -> TExp t -> ImpM rep r op ()
dPrimV_ [VName]
is forall a b. (a -> b) -> a -> b
$ forall num. IntegralExp num => [num] -> num -> [num]
unflattenIndex [TExp Int64]
ns_64 TExp Int64
i
        forall {k} (rep :: k) r op.
Names -> Stms rep -> ImpM rep r op () -> ImpM rep r op ()
compileStms forall a. Monoid a => a
mempty (forall {k} (rep :: k). KernelBody rep -> Stms rep
kernelBodyStms KernelBody MCMem
kbody) forall a b. (a -> b) -> a -> b
$ do
          let ([SubExp]
red_res, [SubExp]
map_res) =
                forall a. Int -> [a] -> ([a], [a])
splitFromEnd (forall (t :: * -> *) a. Foldable t => t a -> Int
length [PatElem LParamMem]
map_pes) forall a b. (a -> b) -> a -> b
$
                  forall a b. (a -> b) -> [a] -> [b]
map KernelResult -> SubExp
kernelResultSubExp forall a b. (a -> b) -> a -> b
$
                    forall {k} (rep :: k). KernelBody rep -> [KernelResult]
kernelBodyResult KernelBody MCMem
kbody

          forall {k} (rep :: k) r op.
Text -> ImpM rep r op () -> ImpM rep r op ()
sComment Text
"save map-out results" forall a b. (a -> b) -> a -> b
$
            forall (t :: * -> *) (m :: * -> *) a b.
(Foldable t, Monad m) =>
t a -> (a -> m b) -> m ()
forM_ (forall a b. [a] -> [b] -> [(a, b)]
zip [PatElem LParamMem]
map_pes [SubExp]
map_res) forall a b. (a -> b) -> a -> b
$ \(PatElem LParamMem
pe, SubExp
res) ->
              forall {k} (rep :: k) r op.
VName -> [TExp Int64] -> SubExp -> [TExp Int64] -> ImpM rep r op ()
copyDWIMFix (forall dec. PatElem dec -> VName
patElemName PatElem LParamMem
pe) (forall a b. (a -> b) -> [a] -> [b]
map forall a. a -> TPrimExp Int64 a
Imp.le64 [VName]
is) SubExp
res []

          forall (t :: * -> *) (m :: * -> *) a b.
(Foldable t, Monad m) =>
t a -> (a -> m b) -> m ()
forM_ (forall a b c. [a] -> [b] -> [c] -> [(a, b, c)]
zip3 [HistOp MCMem]
histops [[VName]]
local_subhistograms (forall {k} (rep :: k).
[HistOp rep] -> [SubExp] -> [([SubExp], [SubExp])]
splitHistResults [HistOp MCMem]
histops [SubExp]
red_res)) forall a b. (a -> b) -> a -> b
$
            \( histop :: HistOp MCMem
histop@(HistOp ShapeBase SubExp
dest_shape SubExp
_ [VName]
_ [SubExp]
_ ShapeBase SubExp
shape Lambda MCMem
_),
               [VName]
histop_subhistograms,
               ([SubExp]
bucket, [SubExp]
vs')
               ) -> do
                HistOp MCMem
histop' <- HistOp MCMem -> MulticoreGen (HistOp MCMem)
renameHistop HistOp MCMem
histop

                let bucket' :: [TExp Int64]
bucket' = forall a b. (a -> b) -> [a] -> [b]
map SubExp -> TExp Int64
pe64 [SubExp]
bucket
                    dest_shape' :: [TExp Int64]
dest_shape' = forall a b. (a -> b) -> [a] -> [b]
map SubExp -> TExp Int64
pe64 forall a b. (a -> b) -> a -> b
$ forall d. ShapeBase d -> [d]
shapeDims ShapeBase SubExp
dest_shape
                    acc_params' :: [Param LParamMem]
acc_params' = (forall {k} (rep :: k). Lambda rep -> [LParam rep]
lambdaParams forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall {k} (rep :: k). HistOp rep -> Lambda rep
histOp) HistOp MCMem
histop'
                    vs_params' :: [Param LParamMem]
vs_params' = forall a. Int -> [a] -> [a]
takeLast (forall (t :: * -> *) a. Foldable t => t a -> Int
length [SubExp]
vs') forall a b. (a -> b) -> a -> b
$ forall {k} (rep :: k). Lambda rep -> [LParam rep]
lambdaParams forall a b. (a -> b) -> a -> b
$ forall {k} (rep :: k). HistOp rep -> Lambda rep
histOp HistOp MCMem
histop'

                (TExp Int64 -> MulticoreGen ()) -> MulticoreGen ()
generateUniformizeLoop forall a b. (a -> b) -> a -> b
$ \TExp Int64
j ->
                  forall {k} (rep :: k) r op.
Text -> ImpM rep r op () -> ImpM rep r op ()
sComment Text
"perform updates" forall a b. (a -> b) -> a -> b
$ do
                    -- Create new set of uniform buckets
                    -- That is extract each bucket from a SIMD vector lane
                    [TV Int64]
extract_buckets <- forall (t :: * -> *) (m :: * -> *) a b.
(Traversable t, Monad m) =>
(a -> m b) -> t a -> m (t b)
mapM (forall {k1} {k2} (rep :: k1) r op (t :: k2).
String -> PrimType -> ImpM rep r op (TV t)
dPrim String
"extract_bucket" forall b c a. (b -> c) -> (a -> b) -> a -> c
. (forall v. PrimExp v -> PrimType
primExpType forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall {k} (t :: k) v. TPrimExp t v -> PrimExp v
untyped)) [TExp Int64]
bucket'
                    forall (t :: * -> *) (m :: * -> *) a b.
(Foldable t, Monad m) =>
t a -> (a -> m b) -> m ()
forM_ (forall a b. [a] -> [b] -> [(a, b)]
zip [TV Int64]
extract_buckets [TExp Int64]
bucket') forall a b. (a -> b) -> a -> b
$ \(TV Int64
x, TExp Int64
y) ->
                      forall {k} op (rep :: k) r. Code op -> ImpM rep r op ()
emit forall a b. (a -> b) -> a -> b
$ forall a. a -> Code a
Imp.Op forall a b. (a -> b) -> a -> b
$ VName -> Exp -> Exp -> Multicore
Imp.ExtractLane (forall {k} (t :: k). TV t -> VName
tvVar TV Int64
x) (forall {k} (t :: k) v. TPrimExp t v -> PrimExp v
untyped TExp Int64
y) (forall {k} (t :: k) v. TPrimExp t v -> PrimExp v
untyped TExp Int64
j)
                    let bucket'' :: [TExp Int64]
bucket'' = forall a b. (a -> b) -> [a] -> [b]
map forall {k} (t :: k). TV t -> TExp t
tvExp [TV Int64]
extract_buckets
                        bucket_in_bounds :: TPrimExp Bool VName
bucket_in_bounds =
                          Slice (TExp Int64) -> [TExp Int64] -> TPrimExp Bool VName
inBounds (forall d. [DimIndex d] -> Slice d
Slice (forall a b. (a -> b) -> [a] -> [b]
map forall d. d -> DimIndex d
DimFix [TExp Int64]
bucket'')) [TExp Int64]
dest_shape'
                    forall {k} (rep :: k) r op.
TPrimExp Bool VName -> ImpM rep r op () -> ImpM rep r op ()
sWhen TPrimExp Bool VName
bucket_in_bounds forall a b. (a -> b) -> a -> b
$ do
                      HistOp MCMem -> MulticoreGen ()
genHistOpParams HistOp MCMem
histop'
                      forall {k} (rep :: k) r op.
ShapeBase SubExp
-> ([TExp Int64] -> ImpM rep r op ()) -> ImpM rep r op ()
sLoopNest ShapeBase SubExp
shape forall a b. (a -> b) -> a -> b
$ \[TExp Int64]
is' -> do
                        -- read values vs and perform lambda writing result back to is
                        forall (t :: * -> *) (m :: * -> *) a b.
(Foldable t, Monad m) =>
t a -> (a -> m b) -> m ()
forM_ (forall a b. [a] -> [b] -> [(a, b)]
zip [Param LParamMem]
vs_params' [SubExp]
vs') forall a b. (a -> b) -> a -> b
$ \(Param LParamMem
p, SubExp
res) ->
                          forall {f :: * -> *} {shape} {u}.
Applicative f =>
TypeBase shape u -> (PrimType -> f ()) -> f ()
ifPrimType (forall dec. Typed dec => Param dec -> Type
paramType Param LParamMem
p) forall a b. (a -> b) -> a -> b
$ \PrimType
pt -> do
                            -- Hack to copy varying load into uniform result variable
                            TV Any
tmp <- forall {k1} {k2} (rep :: k1) r op (t :: k2).
String -> PrimType -> ImpM rep r op (TV t)
dPrim String
"tmp" PrimType
pt
                            forall {k} (rep :: k) r op.
VName -> [TExp Int64] -> SubExp -> [TExp Int64] -> ImpM rep r op ()
copyDWIMFix (forall {k} (t :: k). TV t -> VName
tvVar TV Any
tmp) [] SubExp
res [TExp Int64]
is'
                            TExp Int64 -> MulticoreGen (Code Multicore) -> MulticoreGen ()
extractVectorLane TExp Int64
j forall a b. (a -> b) -> a -> b
$
                              forall (f :: * -> *) a. Applicative f => a -> f a
pure forall a b. (a -> b) -> a -> b
$
                                forall a. VName -> Exp -> Code a
Imp.SetScalar (forall dec. Param dec -> VName
paramName Param LParamMem
p) (forall v. v -> PrimType -> PrimExp v
Imp.LeafExp (forall {k} (t :: k). TV t -> VName
tvVar TV Any
tmp) PrimType
pt)
                        HistOp MCMem
-> [VName]
-> [TExp Int64]
-> TExp Int64
-> [Param LParamMem]
-> MulticoreGen ()
updateHisto HistOp MCMem
histop' [VName]
histop_subhistograms ([TExp Int64]
bucket'' forall a. [a] -> [a] -> [a]
++ [TExp Int64]
is') TExp Int64
j [Param LParamMem]
acc_params'

    -- Copy the task-local subhistograms to the global subhistograms,
    -- where they will be combined.
    forall (t :: * -> *) (m :: * -> *) a b.
(Foldable t, Monad m) =>
t a -> (a -> m b) -> m ()
forM_ (forall a b. [a] -> [b] -> [(a, b)]
zip (forall (t :: * -> *) a. Foldable t => t [a] -> [a]
concat [[VName]]
global_subhistograms) (forall (t :: * -> *) a. Foldable t => t [a] -> [a]
concat [[VName]]
local_subhistograms)) forall a b. (a -> b) -> a -> b
$
      \(VName
global, VName
local) -> forall {k} (rep :: k) r op.
VName -> [TExp Int64] -> SubExp -> [TExp Int64] -> ImpM rep r op ()
copyDWIMFix VName
global [TExp Int64
tid'] (VName -> SubExp
Var VName
local) []

  [Param]
free_params <- forall a. FreeIn a => a -> MulticoreGen [Param]
freeParams Code Multicore
body
  forall {k} op (rep :: k) r. Code op -> ImpM rep r op ()
emit forall a b. (a -> b) -> a -> b
$ forall a. a -> Code a
Imp.Op forall a b. (a -> b) -> a -> b
$ String -> Code Multicore -> [Param] -> Multicore
Imp.ParLoop String
"seghist_stage_1" Code Multicore
body [Param]
free_params

  -- Perform a segmented reduction over the subhistograms
  forall (t :: * -> *) (m :: * -> *) a b.
(Foldable t, Monad m) =>
t a -> (a -> m b) -> m ()
forM_ (forall a b c. [a] -> [b] -> [c] -> [(a, b, c)]
zip3 [[PatElem LParamMem]]
per_red_pes [[VName]]
global_subhistograms [HistOp MCMem]
histops) forall a b. (a -> b) -> a -> b
$ \([PatElem LParamMem]
red_pes, [VName]
hists, HistOp MCMem
op) -> do
    [VName]
bucket_ids <-
      forall (m :: * -> *) a. Applicative m => Int -> m a -> m [a]
replicateM (forall a. ArrayShape a => a -> Int
shapeRank (forall {k} (rep :: k). HistOp rep -> ShapeBase SubExp
histShape HistOp MCMem
op)) (forall (m :: * -> *). MonadFreshNames m => String -> m VName
newVName String
"bucket_id")
    VName
subhistogram_id <- forall (m :: * -> *). MonadFreshNames m => String -> m VName
newVName String
"subhistogram_id"

    let segred_space :: SegSpace
segred_space =
          VName -> [(VName, SubExp)] -> SegSpace
SegSpace (SegSpace -> VName
segFlat SegSpace
space) forall a b. (a -> b) -> a -> b
$
            [(VName, SubExp)]
segment_dims
              forall a. [a] -> [a] -> [a]
++ forall a b. [a] -> [b] -> [(a, b)]
zip [VName]
bucket_ids (forall d. ShapeBase d -> [d]
shapeDims (forall {k} (rep :: k). HistOp rep -> ShapeBase SubExp
histShape HistOp MCMem
op))
              forall a. [a] -> [a] -> [a]
++ [(VName
subhistogram_id, forall {k} (t :: k). TV t -> SubExp
tvSize TV Int32
num_histos)]

        segred_op :: SegBinOp MCMem
segred_op = forall {k} (rep :: k).
Commutativity
-> Lambda rep -> [SubExp] -> ShapeBase SubExp -> SegBinOp rep
SegBinOp Commutativity
Noncommutative (forall {k} (rep :: k). HistOp rep -> Lambda rep
histOp HistOp MCMem
op) (forall {k} (rep :: k). HistOp rep -> [SubExp]
histNeutral HistOp MCMem
op) (forall {k} (rep :: k). HistOp rep -> ShapeBase SubExp
histOpShape HistOp MCMem
op)

    Code Multicore
red_code <- forall {k} (rep :: k) r op.
ImpM rep r op () -> ImpM rep r op (Code op)
collect forall a b. (a -> b) -> a -> b
$ do
      TV Int32
nsubtasks <- forall {k1} {k2} (rep :: k1) r op (t :: k2).
String -> PrimType -> ImpM rep r op (TV t)
dPrim String
"nsubtasks" PrimType
int32
      forall {k} op (rep :: k) r. op -> ImpM rep r op ()
sOp forall a b. (a -> b) -> a -> b
$ VName -> Multicore
Imp.GetNumTasks forall a b. (a -> b) -> a -> b
$ forall {k} (t :: k). TV t -> VName
tvVar TV Int32
nsubtasks
      forall {k} op (rep :: k) r. Code op -> ImpM rep r op ()
emit forall (m :: * -> *) b c a.
Monad m =>
(b -> m c) -> (a -> m b) -> a -> m c
<=< Pat LParamMem
-> SegSpace
-> [SegBinOp MCMem]
-> TV Int32
-> DoSegBody
-> MulticoreGen (Code Multicore)
compileSegRed' (forall dec. [PatElem dec] -> Pat dec
Pat [PatElem LParamMem]
red_pes) SegSpace
segred_space [SegBinOp MCMem
segred_op] TV Int32
nsubtasks forall a b. (a -> b) -> a -> b
$ \[[(SubExp, [TExp Int64])]] -> MulticoreGen ()
red_cont ->
        [[(SubExp, [TExp Int64])]] -> MulticoreGen ()
red_cont forall a b. (a -> b) -> a -> b
$
          forall {k} (rep :: k) a. [SegBinOp rep] -> [a] -> [[a]]
segBinOpChunks [SegBinOp MCMem
segred_op] forall a b. (a -> b) -> a -> b
$
            forall a b c. (a -> b -> c) -> b -> a -> c
flip forall a b. (a -> b) -> [a] -> [b]
map [VName]
hists forall a b. (a -> b) -> a -> b
$ \VName
subhisto ->
              ( VName -> SubExp
Var VName
subhisto,
                forall a b. (a -> b) -> [a] -> [b]
map forall a. a -> TPrimExp Int64 a
Imp.le64 forall a b. (a -> b) -> a -> b
$
                  forall a b. (a -> b) -> [a] -> [b]
map forall a b. (a, b) -> a
fst [(VName, SubExp)]
segment_dims forall a. [a] -> [a] -> [a]
++ [VName
subhistogram_id] forall a. [a] -> [a] -> [a]
++ [VName]
bucket_ids
              )

    let ns_red :: [TExp Int64]
ns_red = forall a b. (a -> b) -> [a] -> [b]
map (SubExp -> TExp Int64
pe64 forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a b. (a, b) -> b
snd) forall a b. (a -> b) -> a -> b
$ SegSpace -> [(VName, SubExp)]
unSegSpace SegSpace
segred_space
        iterations :: TExp Int64
iterations = forall (t :: * -> *) a. (Foldable t, Num a) => t a -> a
product forall a b. (a -> b) -> a -> b
$ forall a. [a] -> [a]
init [TExp Int64]
ns_red -- The segmented reduction is sequential over the inner most dimension
        scheduler_info :: SchedulerInfo
scheduler_info = Exp -> Scheduling -> SchedulerInfo
Imp.SchedulerInfo (forall {k} (t :: k) v. TPrimExp t v -> PrimExp v
untyped TExp Int64
iterations) Scheduling
Imp.Static
        red_task :: ParallelTask
red_task = Code Multicore -> ParallelTask
Imp.ParallelTask Code Multicore
red_code
    [Param]
free_params_red <- forall a. FreeIn a => a -> MulticoreGen [Param]
freeParams Code Multicore
red_code
    forall {k} op (rep :: k) r. Code op -> ImpM rep r op ()
emit forall a b. (a -> b) -> a -> b
$ forall a. a -> Code a
Imp.Op forall a b. (a -> b) -> a -> b
$ String
-> [Param]
-> ParallelTask
-> Maybe ParallelTask
-> [Param]
-> SchedulerInfo
-> Multicore
Imp.SegOp String
"seghist_red" [Param]
free_params_red ParallelTask
red_task forall a. Maybe a
Nothing forall a. Monoid a => a
mempty SchedulerInfo
scheduler_info
  where
    segment_dims :: [(VName, SubExp)]
segment_dims = forall a. [a] -> [a]
init forall a b. (a -> b) -> a -> b
$ SegSpace -> [(VName, SubExp)]
unSegSpace SegSpace
space
    ifPrimType :: TypeBase shape u -> (PrimType -> f ()) -> f ()
ifPrimType (Prim PrimType
pt) PrimType -> f ()
f = PrimType -> f ()
f PrimType
pt
    ifPrimType TypeBase shape u
_ PrimType -> f ()
_ = forall (f :: * -> *) a. Applicative f => a -> f a
pure ()

-- Note: This isn't currently used anywhere.
-- This implementation for a Segmented Hist only
-- parallelize over the segments,
-- where each segment is updated sequentially.
segmentedHist ::
  Pat LetDecMem ->
  SegSpace ->
  [HistOp MCMem] ->
  KernelBody MCMem ->
  MulticoreGen Imp.MCCode
segmentedHist :: Pat LParamMem
-> SegSpace
-> [HistOp MCMem]
-> KernelBody MCMem
-> MulticoreGen (Code Multicore)
segmentedHist Pat LParamMem
pat SegSpace
space [HistOp MCMem]
histops KernelBody MCMem
kbody = do
  forall {k} op (rep :: k) r. Code op -> ImpM rep r op ()
emit forall a b. (a -> b) -> a -> b
$ forall a. String -> Maybe Exp -> Code a
Imp.DebugPrint String
"Segmented segHist" forall a. Maybe a
Nothing
  forall {k} (rep :: k) r op.
ImpM rep r op () -> ImpM rep r op (Code op)
collect forall a b. (a -> b) -> a -> b
$ do
    Code Multicore
body <- Pat LParamMem
-> SegSpace
-> [HistOp MCMem]
-> KernelBody MCMem
-> MulticoreGen (Code Multicore)
compileSegHistBody Pat LParamMem
pat SegSpace
space [HistOp MCMem]
histops KernelBody MCMem
kbody
    [Param]
free_params <- forall a. FreeIn a => a -> MulticoreGen [Param]
freeParams Code Multicore
body
    forall {k} op (rep :: k) r. Code op -> ImpM rep r op ()
emit forall a b. (a -> b) -> a -> b
$ forall a. a -> Code a
Imp.Op forall a b. (a -> b) -> a -> b
$ String -> Code Multicore -> [Param] -> Multicore
Imp.ParLoop String
"segmented_hist" Code Multicore
body [Param]
free_params

compileSegHistBody ::
  Pat LetDecMem ->
  SegSpace ->
  [HistOp MCMem] ->
  KernelBody MCMem ->
  MulticoreGen Imp.MCCode
compileSegHistBody :: Pat LParamMem
-> SegSpace
-> [HistOp MCMem]
-> KernelBody MCMem
-> MulticoreGen (Code Multicore)
compileSegHistBody Pat LParamMem
pat SegSpace
space [HistOp MCMem]
histops KernelBody MCMem
kbody = forall {k} (rep :: k) r op.
ImpM rep r op () -> ImpM rep r op (Code op)
collect forall a b. (a -> b) -> a -> b
$ do
  let ([VName]
is, [SubExp]
ns) = forall a b. [(a, b)] -> ([a], [b])
unzip forall a b. (a -> b) -> a -> b
$ SegSpace -> [(VName, SubExp)]
unSegSpace SegSpace
space
      ns_64 :: [TExp Int64]
ns_64 = forall a b. (a -> b) -> [a] -> [b]
map SubExp -> TExp Int64
pe64 [SubExp]
ns

  let num_red_res :: Int
num_red_res = forall (t :: * -> *) a. Foldable t => t a -> Int
length [HistOp MCMem]
histops forall a. Num a => a -> a -> a
+ forall (t :: * -> *) a. (Foldable t, Num a) => t a -> a
sum (forall a b. (a -> b) -> [a] -> [b]
map (forall (t :: * -> *) a. Foldable t => t a -> Int
length forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall {k} (rep :: k). HistOp rep -> [SubExp]
histNeutral) [HistOp MCMem]
histops)
      map_pes :: [PatElem LParamMem]
map_pes = forall a. Int -> [a] -> [a]
drop Int
num_red_res forall a b. (a -> b) -> a -> b
$ forall dec. Pat dec -> [PatElem dec]
patElems Pat LParamMem
pat
      per_red_pes :: [[PatElem LParamMem]]
per_red_pes = forall {k} (rep :: k) a. [HistOp rep] -> [a] -> [[a]]
segHistOpChunks [HistOp MCMem]
histops forall a b. (a -> b) -> a -> b
$ forall dec. Pat dec -> [PatElem dec]
patElems Pat LParamMem
pat

  forall {k} (rep :: k) r op. VName -> PrimType -> ImpM rep r op ()
dPrim_ (SegSpace -> VName
segFlat SegSpace
space) PrimType
int64
  forall {k} op (rep :: k) r. op -> ImpM rep r op ()
sOp forall a b. (a -> b) -> a -> b
$ VName -> Multicore
Imp.GetTaskId (SegSpace -> VName
segFlat SegSpace
space)

  String
-> ChunkLoopVectorization
-> (TExp Int64 -> MulticoreGen ())
-> MulticoreGen ()
generateChunkLoop String
"SegHist" ChunkLoopVectorization
Scalar forall a b. (a -> b) -> a -> b
$ \TExp Int64
idx -> do
    let inner_bound :: TExp Int64
inner_bound = forall a. [a] -> a
last [TExp Int64]
ns_64
    forall {k1} {k2} (t :: k1) (rep :: k2) r op.
String
-> TExp t -> (TExp t -> ImpM rep r op ()) -> ImpM rep r op ()
sFor String
"i" TExp Int64
inner_bound forall a b. (a -> b) -> a -> b
$ \TExp Int64
i -> do
      forall (m :: * -> *) a b c.
Applicative m =>
(a -> b -> m c) -> [a] -> [b] -> m ()
zipWithM_ forall {k1} {k2} (t :: k1) (rep :: k2) r op.
VName -> TExp t -> ImpM rep r op ()
dPrimV_ (forall a. [a] -> [a]
init [VName]
is) forall a b. (a -> b) -> a -> b
$ forall num. IntegralExp num => [num] -> num -> [num]
unflattenIndex (forall a. [a] -> [a]
init [TExp Int64]
ns_64) TExp Int64
idx
      forall {k1} {k2} (t :: k1) (rep :: k2) r op.
VName -> TExp t -> ImpM rep r op ()
dPrimV_ (forall a. [a] -> a
last [VName]
is) TExp Int64
i

      forall {k} (rep :: k) r op.
Names -> Stms rep -> ImpM rep r op () -> ImpM rep r op ()
compileStms forall a. Monoid a => a
mempty (forall {k} (rep :: k). KernelBody rep -> Stms rep
kernelBodyStms KernelBody MCMem
kbody) forall a b. (a -> b) -> a -> b
$ do
        let ([SubExp]
red_res, [SubExp]
map_res) =
              forall a. Int -> [a] -> ([a], [a])
splitFromEnd (forall (t :: * -> *) a. Foldable t => t a -> Int
length [PatElem LParamMem]
map_pes) forall a b. (a -> b) -> a -> b
$
                forall a b. (a -> b) -> [a] -> [b]
map KernelResult -> SubExp
kernelResultSubExp forall a b. (a -> b) -> a -> b
$
                  forall {k} (rep :: k). KernelBody rep -> [KernelResult]
kernelBodyResult KernelBody MCMem
kbody
        forall (t :: * -> *) (m :: * -> *) a b.
(Foldable t, Monad m) =>
t a -> (a -> m b) -> m ()
forM_ (forall a b c. [a] -> [b] -> [c] -> [(a, b, c)]
zip3 [[PatElem LParamMem]]
per_red_pes [HistOp MCMem]
histops (forall {k} (rep :: k).
[HistOp rep] -> [SubExp] -> [([SubExp], [SubExp])]
splitHistResults [HistOp MCMem]
histops [SubExp]
red_res)) forall a b. (a -> b) -> a -> b
$
          \([PatElem LParamMem]
red_pes, HistOp ShapeBase SubExp
dest_shape SubExp
_ [VName]
_ [SubExp]
_ ShapeBase SubExp
shape Lambda MCMem
lam, ([SubExp]
bucket, [SubExp]
vs')) -> do
            let ([Param LParamMem]
is_params, [Param LParamMem]
vs_params) = forall a. Int -> [a] -> ([a], [a])
splitAt (forall (t :: * -> *) a. Foldable t => t a -> Int
length [SubExp]
vs') forall a b. (a -> b) -> a -> b
$ forall {k} (rep :: k). Lambda rep -> [LParam rep]
lambdaParams Lambda MCMem
lam
                bucket' :: [TExp Int64]
bucket' = forall a b. (a -> b) -> [a] -> [b]
map SubExp -> TExp Int64
pe64 [SubExp]
bucket
                dest_shape' :: [TExp Int64]
dest_shape' = forall a b. (a -> b) -> [a] -> [b]
map SubExp -> TExp Int64
pe64 forall a b. (a -> b) -> a -> b
$ forall d. ShapeBase d -> [d]
shapeDims ShapeBase SubExp
dest_shape
                bucket_in_bounds :: TPrimExp Bool VName
bucket_in_bounds = Slice (TExp Int64) -> [TExp Int64] -> TPrimExp Bool VName
inBounds (forall d. [DimIndex d] -> Slice d
Slice (forall a b. (a -> b) -> [a] -> [b]
map forall d. d -> DimIndex d
DimFix [TExp Int64]
bucket')) [TExp Int64]
dest_shape'

            forall {k} (rep :: k) r op.
Text -> ImpM rep r op () -> ImpM rep r op ()
sComment Text
"save map-out results" forall a b. (a -> b) -> a -> b
$
              forall (t :: * -> *) (m :: * -> *) a b.
(Foldable t, Monad m) =>
t a -> (a -> m b) -> m ()
forM_ (forall a b. [a] -> [b] -> [(a, b)]
zip [PatElem LParamMem]
map_pes [SubExp]
map_res) forall a b. (a -> b) -> a -> b
$ \(PatElem LParamMem
pe, SubExp
res) ->
                forall {k} (rep :: k) r op.
VName -> [TExp Int64] -> SubExp -> [TExp Int64] -> ImpM rep r op ()
copyDWIMFix (forall dec. PatElem dec -> VName
patElemName PatElem LParamMem
pe) (forall a b. (a -> b) -> [a] -> [b]
map forall a. a -> TPrimExp Int64 a
Imp.le64 [VName]
is) SubExp
res []

            forall {k} (rep :: k) r op.
Text -> ImpM rep r op () -> ImpM rep r op ()
sComment Text
"perform updates" forall a b. (a -> b) -> a -> b
$
              forall {k} (rep :: k) r op.
TPrimExp Bool VName -> ImpM rep r op () -> ImpM rep r op ()
sWhen TPrimExp Bool VName
bucket_in_bounds forall a b. (a -> b) -> a -> b
$ do
                forall {k} (rep :: k) inner r op.
Mem rep inner =>
[LParam rep] -> ImpM rep r op ()
dLParams forall a b. (a -> b) -> a -> b
$ forall {k} (rep :: k). Lambda rep -> [LParam rep]
lambdaParams Lambda MCMem
lam
                forall {k} (rep :: k) r op.
ShapeBase SubExp
-> ([TExp Int64] -> ImpM rep r op ()) -> ImpM rep r op ()
sLoopNest ShapeBase SubExp
shape forall a b. (a -> b) -> a -> b
$ \[TExp Int64]
vec_is -> do
                  -- Index
                  forall (t :: * -> *) (m :: * -> *) a b.
(Foldable t, Monad m) =>
t a -> (a -> m b) -> m ()
forM_ (forall a b. [a] -> [b] -> [(a, b)]
zip [PatElem LParamMem]
red_pes [Param LParamMem]
is_params) forall a b. (a -> b) -> a -> b
$ \(PatElem LParamMem
pe, Param LParamMem
p) ->
                    forall {k} (rep :: k) r op.
VName -> [TExp Int64] -> SubExp -> [TExp Int64] -> ImpM rep r op ()
copyDWIMFix
                      (forall dec. Param dec -> VName
paramName Param LParamMem
p)
                      []
                      (VName -> SubExp
Var forall a b. (a -> b) -> a -> b
$ forall dec. PatElem dec -> VName
patElemName PatElem LParamMem
pe)
                      (forall a b. (a -> b) -> [a] -> [b]
map forall a. a -> TPrimExp Int64 a
Imp.le64 (forall a. [a] -> [a]
init [VName]
is) forall a. [a] -> [a] -> [a]
++ [TExp Int64]
bucket' forall a. [a] -> [a] -> [a]
++ [TExp Int64]
vec_is)
                  -- Value at index
                  forall (t :: * -> *) (m :: * -> *) a b.
(Foldable t, Monad m) =>
t a -> (a -> m b) -> m ()
forM_ (forall a b. [a] -> [b] -> [(a, b)]
zip [Param LParamMem]
vs_params [SubExp]
vs') forall a b. (a -> b) -> a -> b
$ \(Param LParamMem
p, SubExp
v) ->
                    forall {k} (rep :: k) r op.
VName -> [TExp Int64] -> SubExp -> [TExp Int64] -> ImpM rep r op ()
copyDWIMFix (forall dec. Param dec -> VName
paramName Param LParamMem
p) [] SubExp
v [TExp Int64]
vec_is
                  forall {k} (rep :: k) r op.
Names -> Stms rep -> ImpM rep r op () -> ImpM rep r op ()
compileStms forall a. Monoid a => a
mempty (forall {k} (rep :: k). Body rep -> Stms rep
bodyStms forall a b. (a -> b) -> a -> b
$ forall {k} (rep :: k). Lambda rep -> Body rep
lambdaBody Lambda MCMem
lam) forall a b. (a -> b) -> a -> b
$
                    forall (t :: * -> *) (m :: * -> *) a b.
(Foldable t, Monad m) =>
t a -> (a -> m b) -> m ()
forM_ (forall a b. [a] -> [b] -> [(a, b)]
zip [PatElem LParamMem]
red_pes forall a b. (a -> b) -> a -> b
$ forall a b. (a -> b) -> [a] -> [b]
map SubExpRes -> SubExp
resSubExp forall a b. (a -> b) -> a -> b
$ forall {k} (rep :: k). Body rep -> Result
bodyResult forall a b. (a -> b) -> a -> b
$ forall {k} (rep :: k). Lambda rep -> Body rep
lambdaBody Lambda MCMem
lam) forall a b. (a -> b) -> a -> b
$
                      \(PatElem LParamMem
pe, SubExp
se) ->
                        forall {k} (rep :: k) r op.
VName -> [TExp Int64] -> SubExp -> [TExp Int64] -> ImpM rep r op ()
copyDWIMFix
                          (forall dec. PatElem dec -> VName
patElemName PatElem LParamMem
pe)
                          (forall a b. (a -> b) -> [a] -> [b]
map forall a. a -> TPrimExp Int64 a
Imp.le64 (forall a. [a] -> [a]
init [VName]
is) forall a. [a] -> [a] -> [a]
++ [TExp Int64]
bucket' forall a. [a] -> [a] -> [a]
++ [TExp Int64]
vec_is)
                          SubExp
se
                          []