{-# LANGUAGE BangPatterns #-}
{-# LANGUAGE DisambiguateRecordFields #-}
{-# LANGUAGE GADTs #-}

module GHC.Cmm.ProcPoint
    ( ProcPointSet, Status(..)
    , callProcPoints, minimalProcPointSet
    , splitAtProcPoints, procPointAnalysis
    , attachContInfoTables
    )
where

import GHC.Prelude hiding (last, unzip, succ, zip)

import GHC.Cmm.BlockId
import GHC.Cmm.CLabel
import GHC.Cmm
import GHC.Cmm.Utils
import GHC.Cmm.Info
import GHC.Cmm.Liveness
import GHC.Cmm.Switch
import Data.List (sortBy)
import GHC.Data.Maybe
import Control.Monad
import GHC.Utils.Outputable
import GHC.Utils.Panic
import GHC.Platform
import GHC.Types.Unique.Supply
import GHC.Cmm.Dataflow.Block
import GHC.Cmm.Dataflow.Collections
import GHC.Cmm.Dataflow
import GHC.Cmm.Dataflow.Graph
import GHC.Cmm.Dataflow.Label

-- Compute a minimal set of proc points for a control-flow graph.

-- Determine a protocol for each proc point (which live variables will
-- be passed as arguments and which will be on the stack).

{-
A proc point is a basic block that, after CPS transformation, will
start a new function.  The entry block of the original function is a
proc point, as is the continuation of each function call.
A third kind of proc point arises if we want to avoid copying code.
Suppose we have code like the following:

  f() {
    if (...) { ..1..; call foo(); ..2..}
    else     { ..3..; call bar(); ..4..}
    x = y + z;
    return x;
  }

The statement 'x = y + z' can be reached from two different proc
points: the continuations of foo() and bar().  We would prefer not to
put a copy in each continuation; instead we would like 'x = y + z' to
be the start of a new procedure to which the continuations can jump:

  f_cps () {
    if (...) { ..1..; push k_foo; jump foo_cps(); }
    else     { ..3..; push k_bar; jump bar_cps(); }
  }
  k_foo() { ..2..; jump k_join(y, z); }
  k_bar() { ..4..; jump k_join(y, z); }
  k_join(y, z) { x = y + z; return x; }

You might think then that a criterion to make a node a proc point is
that it is directly reached by two distinct proc points.  (Note
[Direct reachability].)  But this criterion is a bit too simple; for
example, 'return x' is also reached by two proc points, yet there is
no point in pulling it out of k_join.  A good criterion would be to
say that a node should be made a proc point if it is reached by a set
of proc points that is different than its immediate dominator.  NR
believes this criterion can be shown to produce a minimum set of proc
points, and given a dominator tree, the proc points can be chosen in
time linear in the number of blocks.  Lacking a dominator analysis,
however, we turn instead to an iterative solution, starting with no
proc points and adding them according to these rules:

  1. The entry block is a proc point.
  2. The continuation of a call is a proc point.
  3. A node is a proc point if it is directly reached by more proc
     points than one of its predecessors.

Because we don't understand the problem very well, we apply rule 3 at
most once per iteration, then recompute the reachability information.
(See Note [No simple dataflow].)  The choice of the new proc point is
arbitrary, and I don't know if the choice affects the final solution,
so I don't know if the number of proc points chosen is the
minimum---but the set will be minimal.



Note [Proc-point analysis]
~~~~~~~~~~~~~~~~~~~~~~~~~~

Given a specified set of proc-points (a set of block-ids), "proc-point
analysis" figures out, for every block, which proc-point it belongs to.
All the blocks belonging to proc-point P will constitute a single
top-level C procedure.

A non-proc-point block B "belongs to" a proc-point P iff B is
reachable from P without going through another proc-point.

Invariant: a block B should belong to at most one proc-point; if it
belongs to two, that's a bug.

Note [Non-existing proc-points]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

On some architectures it might happen that the list of proc-points
computed before stack layout pass will be invalidated by the stack
layout. This will happen if stack layout removes from the graph
blocks that were determined to be proc-points. Later on in the pipeline
we use list of proc-points to perform [Proc-point analysis], but
if a proc-point does not exist anymore then we will get compiler panic.
See #8205.
-}

type ProcPointSet = LabelSet

data Status
  = ReachedBy ProcPointSet  -- set of proc points that directly reach the block
  | ProcPoint               -- this block is itself a proc point

instance Outputable Status where
  ppr :: Status -> SDoc
ppr (ReachedBy ProcPointSet
ps)
      | ProcPointSet -> Bool
forall set. IsSet set => set -> Bool
setNull ProcPointSet
ps = String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"<not-reached>"
      | Bool
otherwise = String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"reached by" SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<+>
                    ([SDoc] -> SDoc
forall doc. IsLine doc => [doc] -> doc
hsep ([SDoc] -> SDoc) -> [SDoc] -> SDoc
forall a b. (a -> b) -> a -> b
$ SDoc -> [SDoc] -> [SDoc]
forall doc. IsLine doc => doc -> [doc] -> [doc]
punctuate SDoc
forall doc. IsLine doc => doc
comma ([SDoc] -> [SDoc]) -> [SDoc] -> [SDoc]
forall a b. (a -> b) -> a -> b
$ (BlockId -> SDoc) -> [BlockId] -> [SDoc]
forall a b. (a -> b) -> [a] -> [b]
map BlockId -> SDoc
forall a. Outputable a => a -> SDoc
ppr ([BlockId] -> [SDoc]) -> [BlockId] -> [SDoc]
forall a b. (a -> b) -> a -> b
$ ProcPointSet -> [ElemOf ProcPointSet]
forall set. IsSet set => set -> [ElemOf set]
setElems ProcPointSet
ps)
  ppr Status
ProcPoint = String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"<procpt>"

--------------------------------------------------
-- Proc point analysis

-- Once you know what the proc-points are, figure out
-- what proc-points each block is reachable from
-- See Note [Proc-point analysis]
procPointAnalysis :: ProcPointSet -> CmmGraph -> LabelMap Status
procPointAnalysis :: ProcPointSet -> CmmGraph -> LabelMap Status
procPointAnalysis ProcPointSet
procPoints cmmGraph :: CmmGraph
cmmGraph@(CmmGraph {g_graph :: forall (n :: Extensibility -> Extensibility -> *).
GenCmmGraph n -> Graph n C C
g_graph = Graph CmmNode C C
graph}) =
    DataflowLattice Status
-> TransferFun' CmmNode Status
-> CmmGraph
-> LabelMap Status
-> LabelMap Status
forall (node :: Extensibility -> Extensibility -> *) f.
NonLocal node =>
DataflowLattice f
-> TransferFun' node f
-> GenCmmGraph node
-> FactBase f
-> FactBase f
analyzeCmmFwd DataflowLattice Status
procPointLattice TransferFun' CmmNode Status
procPointTransfer CmmGraph
cmmGraph LabelMap Status
initProcPoints
  where
    initProcPoints :: LabelMap Status
initProcPoints =
        DataflowLattice Status -> [(BlockId, Status)] -> LabelMap Status
forall f. DataflowLattice f -> [(BlockId, f)] -> FactBase f
mkFactBase
            DataflowLattice Status
procPointLattice
            [ (BlockId
id, Status
ProcPoint)
            | BlockId
id <- ProcPointSet -> [ElemOf ProcPointSet]
forall set. IsSet set => set -> [ElemOf set]
setElems ProcPointSet
procPoints
            -- See Note [Non-existing proc-points]
            , ElemOf ProcPointSet
BlockId
id ElemOf ProcPointSet -> ProcPointSet -> Bool
forall set. IsSet set => ElemOf set -> set -> Bool
`setMember` ProcPointSet
labelsInGraph
            ]
    labelsInGraph :: ProcPointSet
labelsInGraph = Graph CmmNode C C -> ProcPointSet
forall (block :: (Extensibility -> Extensibility -> *)
                 -> Extensibility -> Extensibility -> *)
       (n :: Extensibility -> Extensibility -> *) (e :: Extensibility)
       (x :: Extensibility).
NonLocal (block n) =>
Graph' block n e x -> ProcPointSet
labelsDefined Graph CmmNode C C
graph

procPointTransfer :: TransferFun Status
procPointTransfer :: TransferFun' CmmNode Status
procPointTransfer Block CmmNode C C
block LabelMap Status
facts =
    let label :: BlockId
label = Block CmmNode C C -> BlockId
forall (x :: Extensibility). Block CmmNode C x -> BlockId
forall (thing :: Extensibility -> Extensibility -> *)
       (x :: Extensibility).
NonLocal thing =>
thing C x -> BlockId
entryLabel Block CmmNode C C
block
        !fact :: Status
fact = case DataflowLattice Status -> BlockId -> LabelMap Status -> Status
forall f. DataflowLattice f -> BlockId -> FactBase f -> f
getFact DataflowLattice Status
procPointLattice BlockId
label LabelMap Status
facts of
            Status
ProcPoint -> ProcPointSet -> Status
ReachedBy (ProcPointSet -> Status) -> ProcPointSet -> Status
forall a b. (a -> b) -> a -> b
$! ElemOf ProcPointSet -> ProcPointSet
forall set. IsSet set => ElemOf set -> set
setSingleton ElemOf ProcPointSet
BlockId
label
            Status
f -> Status
f
        result :: [(BlockId, Status)]
result = (BlockId -> (BlockId, Status)) -> [BlockId] -> [(BlockId, Status)]
forall a b. (a -> b) -> [a] -> [b]
map (\BlockId
id -> (BlockId
id, Status
fact)) (Block CmmNode C C -> [BlockId]
forall (e :: Extensibility). Block CmmNode e C -> [BlockId]
forall (thing :: Extensibility -> Extensibility -> *)
       (e :: Extensibility).
NonLocal thing =>
thing e C -> [BlockId]
successors Block CmmNode C C
block)
    in DataflowLattice Status -> [(BlockId, Status)] -> LabelMap Status
forall f. DataflowLattice f -> [(BlockId, f)] -> FactBase f
mkFactBase DataflowLattice Status
procPointLattice [(BlockId, Status)]
result

procPointLattice :: DataflowLattice Status
procPointLattice :: DataflowLattice Status
procPointLattice = Status -> JoinFun Status -> DataflowLattice Status
forall a. a -> JoinFun a -> DataflowLattice a
DataflowLattice Status
unreached JoinFun Status
add_to
  where
    unreached :: Status
unreached = ProcPointSet -> Status
ReachedBy ProcPointSet
forall set. IsSet set => set
setEmpty
    add_to :: JoinFun Status
add_to (OldFact Status
ProcPoint) NewFact Status
_ = Status -> JoinedFact Status
forall a. a -> JoinedFact a
NotChanged Status
ProcPoint
    add_to OldFact Status
_ (NewFact Status
ProcPoint) = Status -> JoinedFact Status
forall a. a -> JoinedFact a
Changed Status
ProcPoint -- because of previous case
    add_to (OldFact (ReachedBy ProcPointSet
p)) (NewFact (ReachedBy ProcPointSet
p'))
        | ProcPointSet -> Int
forall set. IsSet set => set -> Int
setSize ProcPointSet
union Int -> Int -> Bool
forall a. Ord a => a -> a -> Bool
> ProcPointSet -> Int
forall set. IsSet set => set -> Int
setSize ProcPointSet
p = Status -> JoinedFact Status
forall a. a -> JoinedFact a
Changed (ProcPointSet -> Status
ReachedBy ProcPointSet
union)
        | Bool
otherwise = Status -> JoinedFact Status
forall a. a -> JoinedFact a
NotChanged (ProcPointSet -> Status
ReachedBy ProcPointSet
p)
      where
        union :: ProcPointSet
union = ProcPointSet -> ProcPointSet -> ProcPointSet
forall set. IsSet set => set -> set -> set
setUnion ProcPointSet
p' ProcPointSet
p

----------------------------------------------------------------------

-- It is worth distinguishing two sets of proc points: those that are
-- induced by calls in the original graph and those that are
-- introduced because they're reachable from multiple proc points.
--
-- Extract the set of Continuation BlockIds, see Note [Continuation BlockIds].
callProcPoints      :: CmmGraph -> ProcPointSet
callProcPoints :: CmmGraph -> ProcPointSet
callProcPoints CmmGraph
g = (ProcPointSet -> Block CmmNode C C -> ProcPointSet)
-> ProcPointSet -> CmmGraph -> ProcPointSet
forall a. (a -> Block CmmNode C C -> a) -> a -> CmmGraph -> a
foldlGraphBlocks ProcPointSet -> Block CmmNode C C -> ProcPointSet
add (ElemOf ProcPointSet -> ProcPointSet
forall set. IsSet set => ElemOf set -> set
setSingleton (CmmGraph -> BlockId
forall (n :: Extensibility -> Extensibility -> *).
GenCmmGraph n -> BlockId
g_entry CmmGraph
g)) CmmGraph
g
  where add :: LabelSet -> CmmBlock -> LabelSet
        add :: ProcPointSet -> Block CmmNode C C -> ProcPointSet
add ProcPointSet
set Block CmmNode C C
b = case Block CmmNode C C -> CmmNode O C
forall (n :: Extensibility -> Extensibility -> *)
       (x :: Extensibility).
Block n x C -> n O C
lastNode Block CmmNode C C
b of
                      CmmCall {cml_cont :: CmmNode O C -> Maybe BlockId
cml_cont = Just BlockId
k} -> ElemOf ProcPointSet -> ProcPointSet -> ProcPointSet
forall set. IsSet set => ElemOf set -> set -> set
setInsert ElemOf ProcPointSet
BlockId
k ProcPointSet
set
                      CmmForeignCall {succ :: CmmNode O C -> BlockId
succ=BlockId
k}     -> ElemOf ProcPointSet -> ProcPointSet -> ProcPointSet
forall set. IsSet set => ElemOf set -> set -> set
setInsert ElemOf ProcPointSet
BlockId
k ProcPointSet
set
                      CmmNode O C
_ -> ProcPointSet
set

minimalProcPointSet :: Platform -> ProcPointSet -> CmmGraph
                    -> UniqSM ProcPointSet
-- Given the set of successors of calls (which must be proc-points)
-- figure out the minimal set of necessary proc-points
minimalProcPointSet :: Platform -> ProcPointSet -> CmmGraph -> UniqSM ProcPointSet
minimalProcPointSet Platform
platform ProcPointSet
callProcPoints CmmGraph
g
  = Platform
-> CmmGraph
-> [Block CmmNode C C]
-> ProcPointSet
-> UniqSM ProcPointSet
extendPPSet Platform
platform CmmGraph
g (CmmGraph -> [Block CmmNode C C]
revPostorder CmmGraph
g) ProcPointSet
callProcPoints

extendPPSet
    :: Platform -> CmmGraph -> [CmmBlock] -> ProcPointSet -> UniqSM ProcPointSet
extendPPSet :: Platform
-> CmmGraph
-> [Block CmmNode C C]
-> ProcPointSet
-> UniqSM ProcPointSet
extendPPSet Platform
platform CmmGraph
g [Block CmmNode C C]
blocks ProcPointSet
procPoints =
    let env :: LabelMap Status
env = ProcPointSet -> CmmGraph -> LabelMap Status
procPointAnalysis ProcPointSet
procPoints CmmGraph
g
        add :: ProcPointSet -> Block CmmNode C C -> ProcPointSet
add ProcPointSet
pps Block CmmNode C C
block = let id :: BlockId
id = Block CmmNode C C -> BlockId
forall (x :: Extensibility). Block CmmNode C x -> BlockId
forall (thing :: Extensibility -> Extensibility -> *)
       (x :: Extensibility).
NonLocal thing =>
thing C x -> BlockId
entryLabel Block CmmNode C C
block
                        in  case KeyOf LabelMap -> LabelMap Status -> Maybe Status
forall a. KeyOf LabelMap -> LabelMap a -> Maybe a
forall (map :: * -> *) a.
IsMap map =>
KeyOf map -> map a -> Maybe a
mapLookup KeyOf LabelMap
BlockId
id LabelMap Status
env of
                              Just Status
ProcPoint -> ElemOf ProcPointSet -> ProcPointSet -> ProcPointSet
forall set. IsSet set => ElemOf set -> set -> set
setInsert ElemOf ProcPointSet
BlockId
id ProcPointSet
pps
                              Maybe Status
_ -> ProcPointSet
pps
        procPoints' :: ProcPointSet
procPoints' = (ProcPointSet -> Block CmmNode C C -> ProcPointSet)
-> ProcPointSet -> CmmGraph -> ProcPointSet
forall a. (a -> Block CmmNode C C -> a) -> a -> CmmGraph -> a
foldlGraphBlocks ProcPointSet -> Block CmmNode C C -> ProcPointSet
add ProcPointSet
forall set. IsSet set => set
setEmpty CmmGraph
g
        newPoints :: [BlockId]
newPoints = (Block CmmNode C C -> Maybe BlockId)
-> [Block CmmNode C C] -> [BlockId]
forall a b. (a -> Maybe b) -> [a] -> [b]
mapMaybe Block CmmNode C C -> Maybe BlockId
ppSuccessor [Block CmmNode C C]
blocks
        newPoint :: Maybe BlockId
newPoint  = [BlockId] -> Maybe BlockId
forall a. [a] -> Maybe a
listToMaybe [BlockId]
newPoints
        ppSuccessor :: Block CmmNode C C -> Maybe BlockId
ppSuccessor Block CmmNode C C
b =
            let nreached :: BlockId -> Int
nreached BlockId
id = case KeyOf LabelMap -> LabelMap Status -> Maybe Status
forall a. KeyOf LabelMap -> LabelMap a -> Maybe a
forall (map :: * -> *) a.
IsMap map =>
KeyOf map -> map a -> Maybe a
mapLookup KeyOf LabelMap
BlockId
id LabelMap Status
env Maybe Status -> Status -> Status
forall a. Maybe a -> a -> a
`orElse`
                                    String -> SDoc -> Status
forall a. HasCallStack => String -> SDoc -> a
pprPanic String
"no ppt" (BlockId -> SDoc
forall a. Outputable a => a -> SDoc
ppr BlockId
id SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<+> Platform -> Block CmmNode C C -> SDoc
forall env a. OutputableP env a => env -> a -> SDoc
pdoc Platform
platform Block CmmNode C C
b) of
                                Status
ProcPoint -> Int
1
                                ReachedBy ProcPointSet
ps -> ProcPointSet -> Int
forall set. IsSet set => set -> Int
setSize ProcPointSet
ps
                block_procpoints :: Int
block_procpoints = BlockId -> Int
nreached (Block CmmNode C C -> BlockId
forall (x :: Extensibility). Block CmmNode C x -> BlockId
forall (thing :: Extensibility -> Extensibility -> *)
       (x :: Extensibility).
NonLocal thing =>
thing C x -> BlockId
entryLabel Block CmmNode C C
b)
                -- Looking for a successor of b that is reached by
                -- more proc points than b and is not already a proc
                -- point.  If found, it can become a proc point.
                newId :: BlockId -> Bool
newId BlockId
succ_id = Bool -> Bool
not (ElemOf ProcPointSet -> ProcPointSet -> Bool
forall set. IsSet set => ElemOf set -> set -> Bool
setMember ElemOf ProcPointSet
BlockId
succ_id ProcPointSet
procPoints') Bool -> Bool -> Bool
&&
                                BlockId -> Int
nreached BlockId
succ_id Int -> Int -> Bool
forall a. Ord a => a -> a -> Bool
> Int
block_procpoints
            in  [BlockId] -> Maybe BlockId
forall a. [a] -> Maybe a
listToMaybe ([BlockId] -> Maybe BlockId) -> [BlockId] -> Maybe BlockId
forall a b. (a -> b) -> a -> b
$ (BlockId -> Bool) -> [BlockId] -> [BlockId]
forall a. (a -> Bool) -> [a] -> [a]
filter BlockId -> Bool
newId ([BlockId] -> [BlockId]) -> [BlockId] -> [BlockId]
forall a b. (a -> b) -> a -> b
$ Block CmmNode C C -> [BlockId]
forall (e :: Extensibility). Block CmmNode e C -> [BlockId]
forall (thing :: Extensibility -> Extensibility -> *)
       (e :: Extensibility).
NonLocal thing =>
thing e C -> [BlockId]
successors Block CmmNode C C
b

    in case Maybe BlockId
newPoint of
         Just BlockId
id ->
             if ElemOf ProcPointSet -> ProcPointSet -> Bool
forall set. IsSet set => ElemOf set -> set -> Bool
setMember ElemOf ProcPointSet
BlockId
id ProcPointSet
procPoints'
                then String -> UniqSM ProcPointSet
forall a. HasCallStack => String -> a
panic String
"added old proc pt"
                else Platform
-> CmmGraph
-> [Block CmmNode C C]
-> ProcPointSet
-> UniqSM ProcPointSet
extendPPSet Platform
platform CmmGraph
g [Block CmmNode C C]
blocks (ElemOf ProcPointSet -> ProcPointSet -> ProcPointSet
forall set. IsSet set => ElemOf set -> set -> set
setInsert ElemOf ProcPointSet
BlockId
id ProcPointSet
procPoints')
         Maybe BlockId
Nothing -> ProcPointSet -> UniqSM ProcPointSet
forall a. a -> UniqSM a
forall (m :: * -> *) a. Monad m => a -> m a
return ProcPointSet
procPoints'


-- At this point, we have found a set of procpoints, each of which should be
-- the entry point of a procedure.
-- Now, we create the procedure for each proc point,
-- which requires that we:
-- 1. build a map from proc points to the blocks reachable from the proc point
-- 2. turn each branch to a proc point into a jump
-- 3. turn calls and returns into jumps
-- 4. build info tables for the procedures -- and update the info table for
--    the SRTs in the entry procedure as well.
-- Input invariant: A block should only be reachable from a single ProcPoint.
-- ToDo: use the _ret naming convention that the old code generator
-- used. -- EZY
splitAtProcPoints :: Platform -> CLabel -> ProcPointSet-> ProcPointSet -> LabelMap Status -> CmmDecl
                  -> UniqSM [CmmDecl]
splitAtProcPoints :: Platform
-> CLabel
-> ProcPointSet
-> ProcPointSet
-> LabelMap Status
-> CmmDecl
-> UniqSM [CmmDecl]
splitAtProcPoints Platform
_ CLabel
_ ProcPointSet
_ ProcPointSet
_ LabelMap Status
_ t :: CmmDecl
t@(CmmData Section
_ CmmStatics
_) = [CmmDecl] -> UniqSM [CmmDecl]
forall a. a -> UniqSM a
forall (m :: * -> *) a. Monad m => a -> m a
return [CmmDecl
t]
splitAtProcPoints Platform
platform CLabel
entry_label ProcPointSet
callPPs ProcPointSet
procPoints LabelMap Status
procMap CmmDecl
cmmProc = do
  -- Build a map from procpoints to the blocks they reach
  let (CmmProc (TopInfo {info_tbls :: CmmTopInfo -> LabelMap CmmInfoTable
info_tbls = LabelMap CmmInfoTable
info_tbls}) CLabel
top_l [GlobalReg]
_ g :: CmmGraph
g@(CmmGraph {g_entry :: forall (n :: Extensibility -> Extensibility -> *).
GenCmmGraph n -> BlockId
g_entry=BlockId
entry})) = CmmDecl
cmmProc

  let add :: map (map a) -> KeyOf map -> KeyOf map -> a -> map (map a)
add map (map a)
graphEnv KeyOf map
procId KeyOf map
bid a
b = KeyOf map -> map a -> map (map a) -> map (map a)
forall a. KeyOf map -> a -> map a -> map a
forall (map :: * -> *) a.
IsMap map =>
KeyOf map -> a -> map a -> map a
mapInsert KeyOf map
procId map a
graph' map (map a)
graphEnv
        where
          graph' :: map a
graph' = KeyOf map -> a -> map a -> map a
forall a. KeyOf map -> a -> map a -> map a
forall (map :: * -> *) a.
IsMap map =>
KeyOf map -> a -> map a -> map a
mapInsert KeyOf map
bid a
b map a
graph
          graph :: map a
graph  = KeyOf map -> map (map a) -> Maybe (map a)
forall a. KeyOf map -> map a -> Maybe a
forall (map :: * -> *) a.
IsMap map =>
KeyOf map -> map a -> Maybe a
mapLookup KeyOf map
procId map (map a)
graphEnv Maybe (map a) -> map a -> map a
forall a. Maybe a -> a -> a
`orElse` map a
forall a. map a
forall (map :: * -> *) a. IsMap map => map a
mapEmpty

  let add_block :: LabelMap (LabelMap CmmBlock) -> CmmBlock -> LabelMap (LabelMap CmmBlock)
      add_block :: LabelMap (LabelMap (Block CmmNode C C))
-> Block CmmNode C C -> LabelMap (LabelMap (Block CmmNode C C))
add_block LabelMap (LabelMap (Block CmmNode C C))
graphEnv Block CmmNode C C
b =
        case KeyOf LabelMap -> LabelMap Status -> Maybe Status
forall a. KeyOf LabelMap -> LabelMap a -> Maybe a
forall (map :: * -> *) a.
IsMap map =>
KeyOf map -> map a -> Maybe a
mapLookup KeyOf LabelMap
BlockId
bid LabelMap Status
procMap of
          Just Status
ProcPoint -> LabelMap (LabelMap (Block CmmNode C C))
-> KeyOf LabelMap
-> KeyOf LabelMap
-> Block CmmNode C C
-> LabelMap (LabelMap (Block CmmNode C C))
forall {map :: * -> *} {map :: * -> *} {a}.
(IsMap map, IsMap map) =>
map (map a) -> KeyOf map -> KeyOf map -> a -> map (map a)
add LabelMap (LabelMap (Block CmmNode C C))
graphEnv KeyOf LabelMap
BlockId
bid KeyOf LabelMap
BlockId
bid Block CmmNode C C
b
          Just (ReachedBy ProcPointSet
set) ->
            case ProcPointSet -> [ElemOf ProcPointSet]
forall set. IsSet set => set -> [ElemOf set]
setElems ProcPointSet
set of
              []   -> LabelMap (LabelMap (Block CmmNode C C))
graphEnv
              [ElemOf ProcPointSet
id] -> LabelMap (LabelMap (Block CmmNode C C))
-> KeyOf LabelMap
-> KeyOf LabelMap
-> Block CmmNode C C
-> LabelMap (LabelMap (Block CmmNode C C))
forall {map :: * -> *} {map :: * -> *} {a}.
(IsMap map, IsMap map) =>
map (map a) -> KeyOf map -> KeyOf map -> a -> map (map a)
add LabelMap (LabelMap (Block CmmNode C C))
graphEnv KeyOf LabelMap
ElemOf ProcPointSet
id KeyOf LabelMap
BlockId
bid Block CmmNode C C
b
              [ElemOf ProcPointSet]
_    -> String -> LabelMap (LabelMap (Block CmmNode C C))
forall a. HasCallStack => String -> a
panic String
"Each block should be reachable from only one ProcPoint"
          Maybe Status
Nothing -> LabelMap (LabelMap (Block CmmNode C C))
graphEnv
        where
          bid :: BlockId
bid = Block CmmNode C C -> BlockId
forall (x :: Extensibility). Block CmmNode C x -> BlockId
forall (thing :: Extensibility -> Extensibility -> *)
       (x :: Extensibility).
NonLocal thing =>
thing C x -> BlockId
entryLabel Block CmmNode C C
b


  let liveness :: BlockEntryLiveness GlobalReg
liveness = Platform -> CmmGraph -> BlockEntryLiveness GlobalReg
cmmGlobalLiveness Platform
platform CmmGraph
g
  let ppLiveness :: BlockId -> [GlobalReg]
ppLiveness BlockId
pp = (GlobalReg -> Bool) -> [GlobalReg] -> [GlobalReg]
forall a. (a -> Bool) -> [a] -> [a]
filter GlobalReg -> Bool
isArgReg ([GlobalReg] -> [GlobalReg]) -> [GlobalReg] -> [GlobalReg]
forall a b. (a -> b) -> a -> b
$ RegSet GlobalReg -> [GlobalReg]
forall r. RegSet r -> [r]
regSetToList (RegSet GlobalReg -> [GlobalReg])
-> RegSet GlobalReg -> [GlobalReg]
forall a b. (a -> b) -> a -> b
$
                        String -> Maybe (RegSet GlobalReg) -> RegSet GlobalReg
forall a. HasCallStack => String -> Maybe a -> a
expectJust String
"ppLiveness" (Maybe (RegSet GlobalReg) -> RegSet GlobalReg)
-> Maybe (RegSet GlobalReg) -> RegSet GlobalReg
forall a b. (a -> b) -> a -> b
$ KeyOf LabelMap
-> BlockEntryLiveness GlobalReg -> Maybe (RegSet GlobalReg)
forall a. KeyOf LabelMap -> LabelMap a -> Maybe a
forall (map :: * -> *) a.
IsMap map =>
KeyOf map -> map a -> Maybe a
mapLookup KeyOf LabelMap
BlockId
pp BlockEntryLiveness GlobalReg
liveness
  LabelMap (LabelMap (Block CmmNode C C))
graphEnv <- LabelMap (LabelMap (Block CmmNode C C))
-> UniqSM (LabelMap (LabelMap (Block CmmNode C C)))
forall a. a -> UniqSM a
forall (m :: * -> *) a. Monad m => a -> m a
return (LabelMap (LabelMap (Block CmmNode C C))
 -> UniqSM (LabelMap (LabelMap (Block CmmNode C C))))
-> LabelMap (LabelMap (Block CmmNode C C))
-> UniqSM (LabelMap (LabelMap (Block CmmNode C C)))
forall a b. (a -> b) -> a -> b
$ (LabelMap (LabelMap (Block CmmNode C C))
 -> Block CmmNode C C -> LabelMap (LabelMap (Block CmmNode C C)))
-> LabelMap (LabelMap (Block CmmNode C C))
-> CmmGraph
-> LabelMap (LabelMap (Block CmmNode C C))
forall a. (a -> Block CmmNode C C -> a) -> a -> CmmGraph -> a
foldlGraphBlocks LabelMap (LabelMap (Block CmmNode C C))
-> Block CmmNode C C -> LabelMap (LabelMap (Block CmmNode C C))
add_block LabelMap (LabelMap (Block CmmNode C C))
forall a. LabelMap a
forall (map :: * -> *) a. IsMap map => map a
mapEmpty CmmGraph
g

  -- Build a map from proc point BlockId to pairs of:
  --  * Labels for their new procedures
  --  * Labels for the info tables of their new procedures (only if
  --    the proc point is a callPP)
  -- Due to common blockification, we may overestimate the set of procpoints.
  let add_label :: LabelMap (CLabel, Maybe CLabel)
-> BlockId -> LabelMap (CLabel, Maybe CLabel)
add_label LabelMap (CLabel, Maybe CLabel)
map BlockId
pp = KeyOf LabelMap
-> (CLabel, Maybe CLabel)
-> LabelMap (CLabel, Maybe CLabel)
-> LabelMap (CLabel, Maybe CLabel)
forall a. KeyOf LabelMap -> a -> LabelMap a -> LabelMap a
forall (map :: * -> *) a.
IsMap map =>
KeyOf map -> a -> map a -> map a
mapInsert KeyOf LabelMap
BlockId
pp (CLabel, Maybe CLabel)
lbls LabelMap (CLabel, Maybe CLabel)
map
        where lbls :: (CLabel, Maybe CLabel)
lbls | BlockId
pp BlockId -> BlockId -> Bool
forall a. Eq a => a -> a -> Bool
== BlockId
entry = (CLabel
entry_label, (CmmInfoTable -> CLabel) -> Maybe CmmInfoTable -> Maybe CLabel
forall a b. (a -> b) -> Maybe a -> Maybe b
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
fmap CmmInfoTable -> CLabel
cit_lbl (KeyOf LabelMap -> LabelMap CmmInfoTable -> Maybe CmmInfoTable
forall a. KeyOf LabelMap -> LabelMap a -> Maybe a
forall (map :: * -> *) a.
IsMap map =>
KeyOf map -> map a -> Maybe a
mapLookup KeyOf LabelMap
BlockId
entry LabelMap CmmInfoTable
info_tbls))
                   | Bool
otherwise   = (CLabel
block_lbl, Bool -> Maybe ()
forall (f :: * -> *). Alternative f => Bool -> f ()
guard (ElemOf ProcPointSet -> ProcPointSet -> Bool
forall set. IsSet set => ElemOf set -> set -> Bool
setMember ElemOf ProcPointSet
BlockId
pp ProcPointSet
callPPs) Maybe () -> Maybe CLabel -> Maybe CLabel
forall a b. Maybe a -> Maybe b -> Maybe b
forall (m :: * -> *) a b. Monad m => m a -> m b -> m b
>>
                                                 CLabel -> Maybe CLabel
forall a. a -> Maybe a
Just CLabel
info_table_lbl)
                   where block_lbl :: CLabel
block_lbl      = BlockId -> CLabel
blockLbl BlockId
pp
                         info_table_lbl :: CLabel
info_table_lbl = BlockId -> CLabel
infoTblLbl BlockId
pp

      procLabels :: LabelMap (CLabel, Maybe CLabel)
      procLabels :: LabelMap (CLabel, Maybe CLabel)
procLabels = (LabelMap (CLabel, Maybe CLabel)
 -> BlockId -> LabelMap (CLabel, Maybe CLabel))
-> LabelMap (CLabel, Maybe CLabel)
-> [BlockId]
-> LabelMap (CLabel, Maybe CLabel)
forall b a. (b -> a -> b) -> b -> [a] -> b
forall (t :: * -> *) b a.
Foldable t =>
(b -> a -> b) -> b -> t a -> b
foldl' LabelMap (CLabel, Maybe CLabel)
-> BlockId -> LabelMap (CLabel, Maybe CLabel)
add_label LabelMap (CLabel, Maybe CLabel)
forall a. LabelMap a
forall (map :: * -> *) a. IsMap map => map a
mapEmpty
                          ((BlockId -> Bool) -> [BlockId] -> [BlockId]
forall a. (a -> Bool) -> [a] -> [a]
filter ((BlockId -> LabelMap (Block CmmNode C C) -> Bool)
-> LabelMap (Block CmmNode C C) -> BlockId -> Bool
forall a b c. (a -> b -> c) -> b -> a -> c
flip KeyOf LabelMap -> LabelMap (Block CmmNode C C) -> Bool
BlockId -> LabelMap (Block CmmNode C C) -> Bool
forall a. KeyOf LabelMap -> LabelMap a -> Bool
forall (map :: * -> *) a. IsMap map => KeyOf map -> map a -> Bool
mapMember (CmmGraph -> LabelMap (Block CmmNode C C)
toBlockMap CmmGraph
g)) (ProcPointSet -> [ElemOf ProcPointSet]
forall set. IsSet set => set -> [ElemOf set]
setElems ProcPointSet
procPoints))

  -- In each new graph, add blocks jumping off to the new procedures,
  -- and replace branches to procpoints with branches to the jump-off blocks
  let add_jump_block :: (LabelMap Label, [CmmBlock])
                     -> (Label, CLabel)
                     -> UniqSM (LabelMap Label, [CmmBlock])
      add_jump_block :: (LabelMap BlockId, [Block CmmNode C C])
-> (BlockId, CLabel)
-> UniqSM (LabelMap BlockId, [Block CmmNode C C])
add_jump_block (LabelMap BlockId
env, [Block CmmNode C C]
bs) (BlockId
pp, CLabel
l) = do
        BlockId
bid <- (Unique -> BlockId) -> UniqSM Unique -> UniqSM BlockId
forall (m :: * -> *) a1 r. Monad m => (a1 -> r) -> m a1 -> m r
liftM Unique -> BlockId
mkBlockId UniqSM Unique
forall (m :: * -> *). MonadUnique m => m Unique
getUniqueM
        let b :: Block CmmNode C C
b    = CmmNode C O
-> Block CmmNode O O -> CmmNode O C -> Block CmmNode C C
forall (n :: Extensibility -> Extensibility -> *).
n C O -> Block n O O -> n O C -> Block n C C
blockJoin (BlockId -> CmmTickScope -> CmmNode C O
CmmEntry BlockId
bid CmmTickScope
GlobalScope) Block CmmNode O O
forall (n :: Extensibility -> Extensibility -> *). Block n O O
emptyBlock CmmNode O C
jump
            live :: [GlobalReg]
live = BlockId -> [GlobalReg]
ppLiveness BlockId
pp
            jump :: CmmNode O C
jump = CmmExpr
-> Maybe BlockId -> [GlobalReg] -> Int -> Int -> Int -> CmmNode O C
CmmCall (CmmLit -> CmmExpr
CmmLit (CLabel -> CmmLit
CmmLabel CLabel
l)) Maybe BlockId
forall a. Maybe a
Nothing [GlobalReg]
live Int
0 Int
0 Int
0
        (LabelMap BlockId, [Block CmmNode C C])
-> UniqSM (LabelMap BlockId, [Block CmmNode C C])
forall a. a -> UniqSM a
forall (m :: * -> *) a. Monad m => a -> m a
return (KeyOf LabelMap -> BlockId -> LabelMap BlockId -> LabelMap BlockId
forall a. KeyOf LabelMap -> a -> LabelMap a -> LabelMap a
forall (map :: * -> *) a.
IsMap map =>
KeyOf map -> a -> map a -> map a
mapInsert KeyOf LabelMap
BlockId
pp BlockId
bid LabelMap BlockId
env, Block CmmNode C C
b Block CmmNode C C -> [Block CmmNode C C] -> [Block CmmNode C C]
forall a. a -> [a] -> [a]
: [Block CmmNode C C]
bs)

  -- when jumping to a PP that has an info table, if
  -- tablesNextToCode is off we must jump to the entry
  -- label instead.
  let tablesNextToCode :: Bool
tablesNextToCode = Platform -> Bool
platformTablesNextToCode Platform
platform

  let jump_label :: Maybe CLabel -> CLabel -> CLabel
jump_label (Just CLabel
info_lbl) CLabel
_
                 | Bool
tablesNextToCode = CLabel
info_lbl
                 | Bool
otherwise        = Platform -> CLabel -> CLabel
toEntryLbl Platform
platform CLabel
info_lbl
      jump_label Maybe CLabel
Nothing  CLabel
block_lbl = CLabel
block_lbl

  let add_if_pp :: BlockId -> [(BlockId, CLabel)] -> [(BlockId, CLabel)]
add_if_pp BlockId
id [(BlockId, CLabel)]
rst =
        case KeyOf LabelMap
-> LabelMap (CLabel, Maybe CLabel) -> Maybe (CLabel, Maybe CLabel)
forall a. KeyOf LabelMap -> LabelMap a -> Maybe a
forall (map :: * -> *) a.
IsMap map =>
KeyOf map -> map a -> Maybe a
mapLookup KeyOf LabelMap
BlockId
id LabelMap (CLabel, Maybe CLabel)
procLabels of
          Just (CLabel
lbl, Maybe CLabel
mb_info_lbl) -> (BlockId
id, Maybe CLabel -> CLabel -> CLabel
jump_label Maybe CLabel
mb_info_lbl CLabel
lbl) (BlockId, CLabel) -> [(BlockId, CLabel)] -> [(BlockId, CLabel)]
forall a. a -> [a] -> [a]
: [(BlockId, CLabel)]
rst
          Maybe (CLabel, Maybe CLabel)
Nothing                 -> [(BlockId, CLabel)]
rst

  let add_if_branch_to_pp :: CmmBlock -> [(BlockId, CLabel)] -> [(BlockId, CLabel)]
      add_if_branch_to_pp :: Block CmmNode C C -> [(BlockId, CLabel)] -> [(BlockId, CLabel)]
add_if_branch_to_pp Block CmmNode C C
block [(BlockId, CLabel)]
rst =
        case Block CmmNode C C -> CmmNode O C
forall (n :: Extensibility -> Extensibility -> *)
       (x :: Extensibility).
Block n x C -> n O C
lastNode Block CmmNode C C
block of
          CmmBranch BlockId
id            -> BlockId -> [(BlockId, CLabel)] -> [(BlockId, CLabel)]
add_if_pp BlockId
id [(BlockId, CLabel)]
rst
          CmmCondBranch CmmExpr
_ BlockId
ti BlockId
fi Maybe Bool
_ -> BlockId -> [(BlockId, CLabel)] -> [(BlockId, CLabel)]
add_if_pp BlockId
ti (BlockId -> [(BlockId, CLabel)] -> [(BlockId, CLabel)]
add_if_pp BlockId
fi [(BlockId, CLabel)]
rst)
          CmmSwitch CmmExpr
_ SwitchTargets
ids         -> (BlockId -> [(BlockId, CLabel)] -> [(BlockId, CLabel)])
-> [(BlockId, CLabel)] -> [BlockId] -> [(BlockId, CLabel)]
forall a b. (a -> b -> b) -> b -> [a] -> b
forall (t :: * -> *) a b.
Foldable t =>
(a -> b -> b) -> b -> t a -> b
foldr BlockId -> [(BlockId, CLabel)] -> [(BlockId, CLabel)]
add_if_pp [(BlockId, CLabel)]
rst ([BlockId] -> [(BlockId, CLabel)])
-> [BlockId] -> [(BlockId, CLabel)]
forall a b. (a -> b) -> a -> b
$ SwitchTargets -> [BlockId]
switchTargetsToList SwitchTargets
ids
          CmmNode O C
_                       -> [(BlockId, CLabel)]
rst

  let add_jumps :: LabelMap CmmGraph -> (Label, LabelMap CmmBlock) -> UniqSM (LabelMap CmmGraph)
      add_jumps :: LabelMap CmmGraph
-> (BlockId, LabelMap (Block CmmNode C C))
-> UniqSM (LabelMap CmmGraph)
add_jumps LabelMap CmmGraph
newGraphEnv (BlockId
ppId, LabelMap (Block CmmNode C C)
blockEnv) = do
        -- find which procpoints we currently branch to
        let needed_jumps :: [(BlockId, CLabel)]
needed_jumps = (Block CmmNode C C -> [(BlockId, CLabel)] -> [(BlockId, CLabel)])
-> [(BlockId, CLabel)]
-> LabelMap (Block CmmNode C C)
-> [(BlockId, CLabel)]
forall a b. (a -> b -> b) -> b -> LabelMap a -> b
forall (map :: * -> *) a b.
IsMap map =>
(a -> b -> b) -> b -> map a -> b
mapFoldr Block CmmNode C C -> [(BlockId, CLabel)] -> [(BlockId, CLabel)]
add_if_branch_to_pp [] LabelMap (Block CmmNode C C)
blockEnv

        (LabelMap BlockId
jumpEnv, [Block CmmNode C C]
jumpBlocks) <-
           ((LabelMap BlockId, [Block CmmNode C C])
 -> (BlockId, CLabel)
 -> UniqSM (LabelMap BlockId, [Block CmmNode C C]))
-> (LabelMap BlockId, [Block CmmNode C C])
-> [(BlockId, CLabel)]
-> UniqSM (LabelMap BlockId, [Block CmmNode C C])
forall (t :: * -> *) (m :: * -> *) b a.
(Foldable t, Monad m) =>
(b -> a -> m b) -> b -> t a -> m b
foldM (LabelMap BlockId, [Block CmmNode C C])
-> (BlockId, CLabel)
-> UniqSM (LabelMap BlockId, [Block CmmNode C C])
add_jump_block (LabelMap BlockId
forall a. LabelMap a
forall (map :: * -> *) a. IsMap map => map a
mapEmpty, []) [(BlockId, CLabel)]
needed_jumps
            -- update the entry block
        let b :: Block CmmNode C C
b = String -> Maybe (Block CmmNode C C) -> Block CmmNode C C
forall a. HasCallStack => String -> Maybe a -> a
expectJust String
"block in env" (Maybe (Block CmmNode C C) -> Block CmmNode C C)
-> Maybe (Block CmmNode C C) -> Block CmmNode C C
forall a b. (a -> b) -> a -> b
$ KeyOf LabelMap
-> LabelMap (Block CmmNode C C) -> Maybe (Block CmmNode C C)
forall a. KeyOf LabelMap -> LabelMap a -> Maybe a
forall (map :: * -> *) a.
IsMap map =>
KeyOf map -> map a -> Maybe a
mapLookup KeyOf LabelMap
BlockId
ppId LabelMap (Block CmmNode C C)
blockEnv
            blockEnv' :: LabelMap (Block CmmNode C C)
blockEnv' = KeyOf LabelMap
-> Block CmmNode C C
-> LabelMap (Block CmmNode C C)
-> LabelMap (Block CmmNode C C)
forall a. KeyOf LabelMap -> a -> LabelMap a -> LabelMap a
forall (map :: * -> *) a.
IsMap map =>
KeyOf map -> a -> map a -> map a
mapInsert KeyOf LabelMap
BlockId
ppId Block CmmNode C C
b LabelMap (Block CmmNode C C)
blockEnv
            -- replace branches to procpoints with branches to jumps
            blockEnv'' :: LabelMap (Block CmmNode C C)
blockEnv'' = CmmGraph -> LabelMap (Block CmmNode C C)
toBlockMap (CmmGraph -> LabelMap (Block CmmNode C C))
-> CmmGraph -> LabelMap (Block CmmNode C C)
forall a b. (a -> b) -> a -> b
$ LabelMap BlockId -> CmmGraph -> CmmGraph
replaceBranches LabelMap BlockId
jumpEnv (CmmGraph -> CmmGraph) -> CmmGraph -> CmmGraph
forall a b. (a -> b) -> a -> b
$ BlockId -> LabelMap (Block CmmNode C C) -> CmmGraph
ofBlockMap BlockId
ppId LabelMap (Block CmmNode C C)
blockEnv'
            -- add the jump blocks to the graph
            blockEnv''' :: LabelMap (Block CmmNode C C)
blockEnv''' = (LabelMap (Block CmmNode C C)
 -> Block CmmNode C C -> LabelMap (Block CmmNode C C))
-> LabelMap (Block CmmNode C C)
-> [Block CmmNode C C]
-> LabelMap (Block CmmNode C C)
forall b a. (b -> a -> b) -> b -> [a] -> b
forall (t :: * -> *) b a.
Foldable t =>
(b -> a -> b) -> b -> t a -> b
foldl' ((Block CmmNode C C
 -> LabelMap (Block CmmNode C C) -> LabelMap (Block CmmNode C C))
-> LabelMap (Block CmmNode C C)
-> Block CmmNode C C
-> LabelMap (Block CmmNode C C)
forall a b c. (a -> b -> c) -> b -> a -> c
flip Block CmmNode C C
-> LabelMap (Block CmmNode C C) -> LabelMap (Block CmmNode C C)
forall (block :: Extensibility -> Extensibility -> *).
(NonLocal block, () :: Constraint) =>
block C C -> LabelMap (block C C) -> LabelMap (block C C)
addBlock) LabelMap (Block CmmNode C C)
blockEnv'' [Block CmmNode C C]
jumpBlocks
        let g' :: CmmGraph
g' = BlockId -> LabelMap (Block CmmNode C C) -> CmmGraph
ofBlockMap BlockId
ppId LabelMap (Block CmmNode C C)
blockEnv'''
        -- pprTrace "g' pre jumps" (ppr g') $ do
        LabelMap CmmGraph -> UniqSM (LabelMap CmmGraph)
forall a. a -> UniqSM a
forall (m :: * -> *) a. Monad m => a -> m a
return (KeyOf LabelMap
-> CmmGraph -> LabelMap CmmGraph -> LabelMap CmmGraph
forall a. KeyOf LabelMap -> a -> LabelMap a -> LabelMap a
forall (map :: * -> *) a.
IsMap map =>
KeyOf map -> a -> map a -> map a
mapInsert KeyOf LabelMap
BlockId
ppId CmmGraph
g' LabelMap CmmGraph
newGraphEnv)

  LabelMap CmmGraph
graphEnv <- (LabelMap CmmGraph
 -> (BlockId, LabelMap (Block CmmNode C C))
 -> UniqSM (LabelMap CmmGraph))
-> LabelMap CmmGraph
-> [(BlockId, LabelMap (Block CmmNode C C))]
-> UniqSM (LabelMap CmmGraph)
forall (t :: * -> *) (m :: * -> *) b a.
(Foldable t, Monad m) =>
(b -> a -> m b) -> b -> t a -> m b
foldM LabelMap CmmGraph
-> (BlockId, LabelMap (Block CmmNode C C))
-> UniqSM (LabelMap CmmGraph)
add_jumps LabelMap CmmGraph
forall a. LabelMap a
forall (map :: * -> *) a. IsMap map => map a
mapEmpty ([(BlockId, LabelMap (Block CmmNode C C))]
 -> UniqSM (LabelMap CmmGraph))
-> [(BlockId, LabelMap (Block CmmNode C C))]
-> UniqSM (LabelMap CmmGraph)
forall a b. (a -> b) -> a -> b
$ LabelMap (LabelMap (Block CmmNode C C))
-> [(KeyOf LabelMap, LabelMap (Block CmmNode C C))]
forall a. LabelMap a -> [(KeyOf LabelMap, a)]
forall (map :: * -> *) a. IsMap map => map a -> [(KeyOf map, a)]
mapToList LabelMap (LabelMap (Block CmmNode C C))
graphEnv

  let to_proc :: (BlockId, CmmGraph) -> CmmDecl
to_proc (BlockId
bid, CmmGraph
g)
          | BlockId
bid BlockId -> BlockId -> Bool
forall a. Eq a => a -> a -> Bool
== BlockId
entry
          =  CmmTopInfo -> CLabel -> [GlobalReg] -> CmmGraph -> CmmDecl
forall d h g. h -> CLabel -> [GlobalReg] -> g -> GenCmmDecl d h g
CmmProc (TopInfo {info_tbls :: LabelMap CmmInfoTable
info_tbls  = LabelMap CmmInfoTable
info_tbls,
                               stack_info :: CmmStackInfo
stack_info = CmmStackInfo
stack_info})
                     CLabel
top_l [GlobalReg]
live CmmGraph
g'
          | Bool
otherwise
          = case String -> Maybe (CLabel, Maybe CLabel) -> (CLabel, Maybe CLabel)
forall a. HasCallStack => String -> Maybe a -> a
expectJust String
"pp label" (Maybe (CLabel, Maybe CLabel) -> (CLabel, Maybe CLabel))
-> Maybe (CLabel, Maybe CLabel) -> (CLabel, Maybe CLabel)
forall a b. (a -> b) -> a -> b
$ KeyOf LabelMap
-> LabelMap (CLabel, Maybe CLabel) -> Maybe (CLabel, Maybe CLabel)
forall a. KeyOf LabelMap -> LabelMap a -> Maybe a
forall (map :: * -> *) a.
IsMap map =>
KeyOf map -> map a -> Maybe a
mapLookup KeyOf LabelMap
BlockId
bid LabelMap (CLabel, Maybe CLabel)
procLabels of
              (CLabel
lbl, Just CLabel
info_lbl)
                 -> CmmTopInfo -> CLabel -> [GlobalReg] -> CmmGraph -> CmmDecl
forall d h g. h -> CLabel -> [GlobalReg] -> g -> GenCmmDecl d h g
CmmProc (TopInfo { info_tbls :: LabelMap CmmInfoTable
info_tbls = KeyOf LabelMap -> CmmInfoTable -> LabelMap CmmInfoTable
forall a. KeyOf LabelMap -> a -> LabelMap a
forall (map :: * -> *) a. IsMap map => KeyOf map -> a -> map a
mapSingleton (CmmGraph -> BlockId
forall (n :: Extensibility -> Extensibility -> *).
GenCmmGraph n -> BlockId
g_entry CmmGraph
g) (CLabel -> CmmInfoTable
mkEmptyContInfoTable CLabel
info_lbl)
                                     , stack_info :: CmmStackInfo
stack_info=CmmStackInfo
stack_info})
                            CLabel
lbl [GlobalReg]
live CmmGraph
g'
              (CLabel
lbl, Maybe CLabel
Nothing)
                 -> CmmTopInfo -> CLabel -> [GlobalReg] -> CmmGraph -> CmmDecl
forall d h g. h -> CLabel -> [GlobalReg] -> g -> GenCmmDecl d h g
CmmProc (TopInfo {info_tbls :: LabelMap CmmInfoTable
info_tbls = LabelMap CmmInfoTable
forall a. LabelMap a
forall (map :: * -> *) a. IsMap map => map a
mapEmpty, stack_info :: CmmStackInfo
stack_info=CmmStackInfo
stack_info})
                            CLabel
lbl [GlobalReg]
live CmmGraph
g'
             where
              g' :: CmmGraph
g' = CmmGraph -> CmmGraph
replacePPIds CmmGraph
g
              live :: [GlobalReg]
live = BlockId -> [GlobalReg]
ppLiveness (CmmGraph -> BlockId
forall (n :: Extensibility -> Extensibility -> *).
GenCmmGraph n -> BlockId
g_entry CmmGraph
g')
              stack_info :: CmmStackInfo
stack_info = StackInfo { arg_space :: Int
arg_space = Int
0
                                     , do_layout :: Bool
do_layout = Bool
True }
                            -- cannot use panic, this is printed by -ddump-cmm

      -- References to procpoint IDs can now be replaced with the
      -- infotable's label
      replacePPIds :: CmmGraph -> CmmGraph
replacePPIds CmmGraph
g = {-# SCC "replacePPIds" #-}
                       (CmmNode C O -> CmmNode C O, CmmNode O O -> CmmNode O O,
 CmmNode O C -> CmmNode O C)
-> CmmGraph -> CmmGraph
mapGraphNodes (CmmNode C O -> CmmNode C O
forall a. a -> a
id, (CmmExpr -> CmmExpr) -> CmmNode O O -> CmmNode O O
forall (e :: Extensibility) (x :: Extensibility).
(CmmExpr -> CmmExpr) -> CmmNode e x -> CmmNode e x
mapExp CmmExpr -> CmmExpr
repl, (CmmExpr -> CmmExpr) -> CmmNode O C -> CmmNode O C
forall (e :: Extensibility) (x :: Extensibility).
(CmmExpr -> CmmExpr) -> CmmNode e x -> CmmNode e x
mapExp CmmExpr -> CmmExpr
repl) CmmGraph
g
        where repl :: CmmExpr -> CmmExpr
repl e :: CmmExpr
e@(CmmLit (CmmBlock BlockId
bid)) =
                case KeyOf LabelMap
-> LabelMap (CLabel, Maybe CLabel) -> Maybe (CLabel, Maybe CLabel)
forall a. KeyOf LabelMap -> LabelMap a -> Maybe a
forall (map :: * -> *) a.
IsMap map =>
KeyOf map -> map a -> Maybe a
mapLookup KeyOf LabelMap
BlockId
bid LabelMap (CLabel, Maybe CLabel)
procLabels of
                  Just (CLabel
_, Just CLabel
info_lbl)  -> CmmLit -> CmmExpr
CmmLit (CLabel -> CmmLit
CmmLabel CLabel
info_lbl)
                  Maybe (CLabel, Maybe CLabel)
_ -> CmmExpr
e
              repl CmmExpr
e = CmmExpr
e

  -- The C back end expects to see return continuations before the
  -- call sites.  Here, we sort them in reverse order -- it gets
  -- reversed later.
  let add_block_num :: (a, map a) -> thing C x -> (a, map a)
add_block_num (a
i, map a
map) thing C x
block =
        (a
i a -> a -> a
forall a. Num a => a -> a -> a
+ a
1, KeyOf map -> a -> map a -> map a
forall a. KeyOf map -> a -> map a -> map a
forall (map :: * -> *) a.
IsMap map =>
KeyOf map -> a -> map a -> map a
mapInsert (thing C x -> BlockId
forall (x :: Extensibility). thing C x -> BlockId
forall (thing :: Extensibility -> Extensibility -> *)
       (x :: Extensibility).
NonLocal thing =>
thing C x -> BlockId
entryLabel thing C x
block) a
i map a
map)
  let (Int
_, LabelMap Int
block_order) =
          ((Int, LabelMap Int) -> Block CmmNode C C -> (Int, LabelMap Int))
-> (Int, LabelMap Int)
-> [Block CmmNode C C]
-> (Int, LabelMap Int)
forall b a. (b -> a -> b) -> b -> [a] -> b
forall (t :: * -> *) b a.
Foldable t =>
(b -> a -> b) -> b -> t a -> b
foldl' (Int, LabelMap Int) -> Block CmmNode C C -> (Int, LabelMap Int)
forall {map :: * -> *} {a}
       {thing :: Extensibility -> Extensibility -> *}
       {x :: Extensibility}.
(KeyOf map ~ BlockId, Num a, IsMap map, NonLocal thing) =>
(a, map a) -> thing C x -> (a, map a)
add_block_num (Int
0::Int, LabelMap Int
forall a. LabelMap a
forall (map :: * -> *) a. IsMap map => map a
mapEmpty :: LabelMap Int)
                (CmmGraph -> [Block CmmNode C C]
revPostorder CmmGraph
g)
  let sort_fn :: (BlockId, CmmGraph) -> (BlockId, CmmGraph) -> Ordering
sort_fn (BlockId
bid, CmmGraph
_) (BlockId
bid', CmmGraph
_) =
        Int -> Int -> Ordering
forall a. Ord a => a -> a -> Ordering
compare (String -> Maybe Int -> Int
forall a. HasCallStack => String -> Maybe a -> a
expectJust String
"block_order" (Maybe Int -> Int) -> Maybe Int -> Int
forall a b. (a -> b) -> a -> b
$ KeyOf LabelMap -> LabelMap Int -> Maybe Int
forall a. KeyOf LabelMap -> LabelMap a -> Maybe a
forall (map :: * -> *) a.
IsMap map =>
KeyOf map -> map a -> Maybe a
mapLookup KeyOf LabelMap
BlockId
bid  LabelMap Int
block_order)
                (String -> Maybe Int -> Int
forall a. HasCallStack => String -> Maybe a -> a
expectJust String
"block_order" (Maybe Int -> Int) -> Maybe Int -> Int
forall a b. (a -> b) -> a -> b
$ KeyOf LabelMap -> LabelMap Int -> Maybe Int
forall a. KeyOf LabelMap -> LabelMap a -> Maybe a
forall (map :: * -> *) a.
IsMap map =>
KeyOf map -> map a -> Maybe a
mapLookup KeyOf LabelMap
BlockId
bid' LabelMap Int
block_order)

  [CmmDecl] -> UniqSM [CmmDecl]
forall a. a -> UniqSM a
forall (m :: * -> *) a. Monad m => a -> m a
return ([CmmDecl] -> UniqSM [CmmDecl]) -> [CmmDecl] -> UniqSM [CmmDecl]
forall a b. (a -> b) -> a -> b
$ ((BlockId, CmmGraph) -> CmmDecl)
-> [(BlockId, CmmGraph)] -> [CmmDecl]
forall a b. (a -> b) -> [a] -> [b]
map (BlockId, CmmGraph) -> CmmDecl
to_proc ([(BlockId, CmmGraph)] -> [CmmDecl])
-> [(BlockId, CmmGraph)] -> [CmmDecl]
forall a b. (a -> b) -> a -> b
$ ((BlockId, CmmGraph) -> (BlockId, CmmGraph) -> Ordering)
-> [(BlockId, CmmGraph)] -> [(BlockId, CmmGraph)]
forall a. (a -> a -> Ordering) -> [a] -> [a]
sortBy (BlockId, CmmGraph) -> (BlockId, CmmGraph) -> Ordering
sort_fn ([(BlockId, CmmGraph)] -> [(BlockId, CmmGraph)])
-> [(BlockId, CmmGraph)] -> [(BlockId, CmmGraph)]
forall a b. (a -> b) -> a -> b
$ LabelMap CmmGraph -> [(KeyOf LabelMap, CmmGraph)]
forall a. LabelMap a -> [(KeyOf LabelMap, a)]
forall (map :: * -> *) a. IsMap map => map a -> [(KeyOf map, a)]
mapToList LabelMap CmmGraph
graphEnv

-- Only called from GHC.Cmm.ProcPoint.splitAtProcPoints. NB. does a
-- recursive lookup, see comment below.
replaceBranches :: LabelMap BlockId -> CmmGraph -> CmmGraph
replaceBranches :: LabelMap BlockId -> CmmGraph -> CmmGraph
replaceBranches LabelMap BlockId
env CmmGraph
cmmg
  = {-# SCC "replaceBranches" #-}
    BlockId -> LabelMap (Block CmmNode C C) -> CmmGraph
ofBlockMap (CmmGraph -> BlockId
forall (n :: Extensibility -> Extensibility -> *).
GenCmmGraph n -> BlockId
g_entry CmmGraph
cmmg) (LabelMap (Block CmmNode C C) -> CmmGraph)
-> LabelMap (Block CmmNode C C) -> CmmGraph
forall a b. (a -> b) -> a -> b
$ (Block CmmNode C C -> Block CmmNode C C)
-> LabelMap (Block CmmNode C C) -> LabelMap (Block CmmNode C C)
forall a b. (a -> b) -> LabelMap a -> LabelMap b
forall (map :: * -> *) a b. IsMap map => (a -> b) -> map a -> map b
mapMap Block CmmNode C C -> Block CmmNode C C
forall {x :: Extensibility}. Block CmmNode x C -> Block CmmNode x C
f (LabelMap (Block CmmNode C C) -> LabelMap (Block CmmNode C C))
-> LabelMap (Block CmmNode C C) -> LabelMap (Block CmmNode C C)
forall a b. (a -> b) -> a -> b
$ CmmGraph -> LabelMap (Block CmmNode C C)
toBlockMap CmmGraph
cmmg
  where
    f :: Block CmmNode x C -> Block CmmNode x C
f Block CmmNode x C
block = Block CmmNode x C -> CmmNode O C -> Block CmmNode x C
forall (n :: Extensibility -> Extensibility -> *)
       (x :: Extensibility).
Block n x C -> n O C -> Block n x C
replaceLastNode Block CmmNode x C
block (CmmNode O C -> Block CmmNode x C)
-> CmmNode O C -> Block CmmNode x C
forall a b. (a -> b) -> a -> b
$ CmmNode O C -> CmmNode O C
last (Block CmmNode x C -> CmmNode O C
forall (n :: Extensibility -> Extensibility -> *)
       (x :: Extensibility).
Block n x C -> n O C
lastNode Block CmmNode x C
block)

    last :: CmmNode O C -> CmmNode O C
    last :: CmmNode O C -> CmmNode O C
last (CmmBranch BlockId
id)          = BlockId -> CmmNode O C
CmmBranch (BlockId -> BlockId
lookup BlockId
id)
    last (CmmCondBranch CmmExpr
e BlockId
ti BlockId
fi Maybe Bool
l) = CmmExpr -> BlockId -> BlockId -> Maybe Bool -> CmmNode O C
CmmCondBranch CmmExpr
e (BlockId -> BlockId
lookup BlockId
ti) (BlockId -> BlockId
lookup BlockId
fi) Maybe Bool
l
    last (CmmSwitch CmmExpr
e SwitchTargets
ids)       = CmmExpr -> SwitchTargets -> CmmNode O C
CmmSwitch CmmExpr
e ((BlockId -> BlockId) -> SwitchTargets -> SwitchTargets
mapSwitchTargets BlockId -> BlockId
lookup SwitchTargets
ids)
    last l :: CmmNode O C
l@(CmmCall {})          = CmmNode O C
l { cml_cont = Nothing }
            -- NB. remove the continuation of a CmmCall, since this
            -- label will now be in a different CmmProc.  Not only
            -- is this tidier, it stops CmmLint from complaining.
    last l :: CmmNode O C
l@(CmmForeignCall {})   = CmmNode O C
l
    lookup :: BlockId -> BlockId
lookup BlockId
id = (BlockId -> BlockId) -> Maybe BlockId -> Maybe BlockId
forall a b. (a -> b) -> Maybe a -> Maybe b
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
fmap BlockId -> BlockId
lookup (KeyOf LabelMap -> LabelMap BlockId -> Maybe BlockId
forall a. KeyOf LabelMap -> LabelMap a -> Maybe a
forall (map :: * -> *) a.
IsMap map =>
KeyOf map -> map a -> Maybe a
mapLookup KeyOf LabelMap
BlockId
id LabelMap BlockId
env) Maybe BlockId -> BlockId -> BlockId
forall a. Maybe a -> a -> a
`orElse` BlockId
id
            -- XXX: this is a recursive lookup, it follows chains
            -- until the lookup returns Nothing, at which point we
            -- return the last BlockId

-- --------------------------------------------------------------
-- Not splitting proc points: add info tables for continuations

attachContInfoTables :: ProcPointSet -> CmmDecl -> CmmDecl
attachContInfoTables :: ProcPointSet -> CmmDecl -> CmmDecl
attachContInfoTables ProcPointSet
call_proc_points (CmmProc CmmTopInfo
top_info CLabel
top_l [GlobalReg]
live CmmGraph
g)
 = CmmTopInfo -> CLabel -> [GlobalReg] -> CmmGraph -> CmmDecl
forall d h g. h -> CLabel -> [GlobalReg] -> g -> GenCmmDecl d h g
CmmProc CmmTopInfo
top_info{info_tbls = info_tbls'} CLabel
top_l [GlobalReg]
live CmmGraph
g
 where
   info_tbls' :: LabelMap CmmInfoTable
info_tbls' = LabelMap CmmInfoTable
-> LabelMap CmmInfoTable -> LabelMap CmmInfoTable
forall a. LabelMap a -> LabelMap a -> LabelMap a
forall (map :: * -> *) a. IsMap map => map a -> map a -> map a
mapUnion (CmmTopInfo -> LabelMap CmmInfoTable
info_tbls CmmTopInfo
top_info) (LabelMap CmmInfoTable -> LabelMap CmmInfoTable)
-> LabelMap CmmInfoTable -> LabelMap CmmInfoTable
forall a b. (a -> b) -> a -> b
$
                [(KeyOf LabelMap, CmmInfoTable)] -> LabelMap CmmInfoTable
forall a. [(KeyOf LabelMap, a)] -> LabelMap a
forall (map :: * -> *) a. IsMap map => [(KeyOf map, a)] -> map a
mapFromList [ (KeyOf LabelMap
BlockId
l, CLabel -> CmmInfoTable
mkEmptyContInfoTable (BlockId -> CLabel
infoTblLbl BlockId
l))
                            | BlockId
l <- ProcPointSet -> [ElemOf ProcPointSet]
forall set. IsSet set => set -> [ElemOf set]
setElems ProcPointSet
call_proc_points
                            , BlockId
l BlockId -> BlockId -> Bool
forall a. Eq a => a -> a -> Bool
/= CmmGraph -> BlockId
forall (n :: Extensibility -> Extensibility -> *).
GenCmmGraph n -> BlockId
g_entry CmmGraph
g ]
attachContInfoTables ProcPointSet
_ CmmDecl
other_decl
 = CmmDecl
other_decl

----------------------------------------------------------------

{-
Note [Direct reachability]
~~~~~~~~~~~~~~~~~~~~~~~~~~
Block B is directly reachable from proc point P iff control can flow
from P to B without passing through an intervening proc point.
-}

----------------------------------------------------------------

{-
Note [No simple dataflow]
~~~~~~~~~~~~~~~~~~~~~~~~~
Sadly, it seems impossible to compute the proc points using a single
dataflow pass.  One might attempt to use this simple lattice:

  data Location = Unknown
                | InProc BlockId -- node is in procedure headed by the named proc point
                | ProcPoint      -- node is itself a proc point

At a join, a node in two different blocks becomes a proc point.
The difficulty is that the change of information during iterative
computation may promote a node prematurely.  Here's a program that
illustrates the difficulty:

  f () {
  entry:
    ....
  L1:
    if (...) { ... }
    else { ... }

  L2: if (...) { g(); goto L1; }
      return x + y;
  }

The only proc-point needed (besides the entry) is L1.  But in an
iterative analysis, consider what happens to L2.  On the first pass
through, it rises from Unknown to 'InProc entry', but when L1 is
promoted to a proc point (because it's the successor of g()), L1's
successors will be promoted to 'InProc L1'.  The problem hits when the
new fact 'InProc L1' flows into L2 which is already bound to 'InProc entry'.
The join operation makes it a proc point when in fact it needn't be,
because its immediate dominator L1 is already a proc point and there
are no other proc points that directly reach L2.
-}



{- Note [Separate Adams optimization]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
It may be worthwhile to attempt the Adams optimization by rewriting
the graph before the assignment of proc-point protocols.  Here are a
couple of rules:

  g() returns to k;                    g() returns to L;
  k: CopyIn c ress; goto L:
   ...                        ==>        ...
  L: // no CopyIn node here            L: CopyIn c ress;


And when c == c' and ress == ress', this also:

  g() returns to k;                    g() returns to L;
  k: CopyIn c ress; goto L:
   ...                        ==>        ...
  L: CopyIn c' ress'                   L: CopyIn c' ress' ;

In both cases the goal is to eliminate k.
-}