, availRegsLattice
, cmmAvailableReloads
, insertLateReloads
- , insertLateReloads'
, removeDeadAssignmentsAndReloads
)
where
import CmmLiveZ
import DFMonad
import MkZipCfg
-import OptimizationFuel
import PprCmm()
import ZipCfg
import ZipCfgCmmRep
import ZipDataflow
-import Maybes
-import Monad
+import Control.Monad
import Outputable hiding (empty)
import qualified Outputable as PP
-import Panic
import UniqSet
-import Maybe
+import Data.Maybe
import Prelude hiding (zip)
-- The point of this module is to insert spills and reloads to
changeStack, changeRegs :: (RegSet -> RegSet) -> DualLive -> DualLive
changeStack f live = live { on_stack = f (on_stack live) }
-changeRegs f live = live { in_regs = f (in_regs live) }
+changeRegs f live = live { in_regs = f (in_regs live) }
dualLiveLattice :: DataflowLattice DualLive
type LiveReloadFix a = FuelMonad (BackwardFixedPoint Middle Last DualLive a)
dualLivenessWithInsertion :: BlockSet -> (LGraph Middle Last) -> FuelMonad (LGraph Middle Last)
-dualLivenessWithInsertion procPoints g =
+dualLivenessWithInsertion procPoints g@(LGraph entry _) =
liftM zdfFpContents $ (res :: LiveReloadFix (LGraph Middle Last))
where res = zdfBRewriteFromL RewriteDeep emptyBlockEnv "dual liveness with insertion"
- dualLiveLattice (dualLiveTransfers procPoints)
- (insertSpillAndReloadRewrites procPoints) empty g
+ dualLiveLattice (dualLiveTransfers entry procPoints)
+ (insertSpillAndReloadRewrites entry procPoints) empty g
empty = fact_bot dualLiveLattice
dualLiveness :: BlockSet -> LGraph Middle Last -> FuelMonad (BlockEnv DualLive)
-dualLiveness procPoints g = liftM zdfFpFacts $ (res :: LiveReloadFix ())
+dualLiveness procPoints g@(LGraph entry _) =
+ liftM zdfFpFacts $ (res :: LiveReloadFix ())
where res = zdfSolveFromL emptyBlockEnv "dual liveness" dualLiveLattice
- (dualLiveTransfers procPoints) empty g
+ (dualLiveTransfers entry procPoints) empty g
empty = fact_bot dualLiveLattice
-dualLiveTransfers :: BlockSet -> BackwardTransfers Middle Last DualLive
-dualLiveTransfers procPoints = BackwardTransfers first middle last
+dualLiveTransfers :: BlockId -> BlockSet -> BackwardTransfers Middle Last DualLive
+dualLiveTransfers entry procPoints = BackwardTransfers first middle last
where last = lastDualLiveness
middle = middleDualLiveness
- first live _id =
- if elemBlockSet _id procPoints then -- live at procPoint => spill
+ first id live = check live id $ -- live at procPoint => spill
+ if id /= entry && elemBlockSet id procPoints then
DualLive { on_stack = on_stack live `plusRegSet` in_regs live
, in_regs = emptyRegSet }
else live
+ check live id x = if id == entry then noLiveOnEntry id (in_regs live) x else x
-middleDualLiveness :: DualLive -> Middle -> DualLive
-middleDualLiveness live m =
- changeStack updSlots $ changeRegs (middleLiveness m) live
- where updSlots live = foldSlotsUsed reload (foldSlotsDefd spill live m) m
+middleDualLiveness :: Middle -> DualLive -> DualLive
+middleDualLiveness m live =
+ changeStack updSlots $ changeRegs (middleLiveness m) (changeRegs regs_in live)
+ where regs_in live = case m of MidForeignCall {} -> emptyRegSet
+ _ -> live
+ updSlots live = foldSlotsUsed reload (foldSlotsDefd spill live m) m
spill live s@(RegSlot r, _, _) = check s $ deleteFromRegSet live r
spill live _ = live
reload live s@(RegSlot r, _, _) = check s $ extendRegSet live r
| o == w && w == widthInBytes (typeWidth ty) = x
check _ _ = panic "middleDualLiveness unsupported: slices"
-lastDualLiveness :: (BlockId -> DualLive) -> Last -> DualLive
-lastDualLiveness env l = last l
- where last (LastReturn _) = empty
- last (LastJump e _) = changeRegs (gen e) empty
- last (LastBranch id) = env id
- last (LastCall tgt Nothing _) = changeRegs (gen tgt) empty
- last (LastCall tgt (Just k) _) =
- -- nothing can be live in registers at this point
- let live = env k in
- if isEmptyUniqSet (in_regs live) then
- DualLive (on_stack live) (gen tgt emptyRegSet)
- else
- pprTrace "Offending party:" (ppr k <+> ppr live) $
- panic "live values in registers at call continuation"
- last (LastCondBranch e t f) = changeRegs (gen e) $ dualUnion (env t) (env f)
- last (LastSwitch e tbl) = changeRegs (gen e) $ dualUnionList $
+lastDualLiveness :: Last -> (BlockId -> DualLive) -> DualLive
+lastDualLiveness l env = last l
+ where last (LastBranch id) = env id
+ last l@(LastCall _ Nothing _ _ _) = changeRegs (gen l . kill l) empty
+ last l@(LastCall _ (Just k) _ _ _) =
+ -- nothing can be live in registers at this point, unless safe foreign call
+ let live = env k
+ live_in = DualLive (on_stack live) (gen l emptyRegSet)
+ in if isEmptyUniqSet (in_regs live) then live_in
+ else pprTrace "Offending party:" (ppr k <+> ppr live) $
+ panic "live values in registers at call continuation"
+ last l@(LastCondBranch _ t f) =
+ changeRegs (gen l . kill l) $ dualUnion (env t) (env f)
+ last l@(LastSwitch _ tbl) = changeRegs (gen l . kill l) $ dualUnionList $
map env (catMaybes tbl)
empty = fact_bot dualLiveLattice
-gen :: UserOfLocalRegs a => a -> RegSet -> RegSet
-gen a live = foldRegsUsed extendRegSet live a
-
-insertSpillAndReloadRewrites :: BlockSet -> BackwardRewrites Middle Last DualLive
-insertSpillAndReloadRewrites procPoints = BackwardRewrites first middle last exit
+gen :: UserOfLocalRegs a => a -> RegSet -> RegSet
+gen a live = foldRegsUsed extendRegSet live a
+kill :: DefinerOfLocalRegs a => a -> RegSet -> RegSet
+kill a live = foldRegsDefd deleteFromRegSet live a
+
+insertSpillAndReloadRewrites ::
+ BlockId -> BlockSet -> BackwardRewrites Middle Last DualLive
+insertSpillAndReloadRewrites entry procPoints =
+ BackwardRewrites first middle last exit
where middle = middleInsertSpillsAndReloads
- last = \_ _ -> Nothing
- exit = Nothing
- first live id =
- if elemBlockSet id procPoints && not (isEmptyUniqSet reloads) then
- Just $ mkMiddles $ map reload $ uniqSetToList reloads
+ last _ _ = Nothing
+ exit = Nothing
+ first id live =
+ if id /= entry && elemBlockSet id procPoints then
+ case map reload (uniqSetToList (in_regs live)) of
+ [] -> Nothing
+ is -> Just (mkMiddles is)
else Nothing
- where reloads = in_regs live
-
-middleInsertSpillsAndReloads :: DualLive -> Middle -> Maybe (AGraph Middle Last)
-middleInsertSpillsAndReloads live m = middle m
+middleInsertSpillsAndReloads :: Middle -> DualLive -> Maybe (AGraph Middle Last)
+middleInsertSpillsAndReloads m live = middle m
where middle (MidAssign (CmmLocal reg) (CmmLoad (CmmStackSlot (RegSlot reg') _) _))
| reg == reg' = Nothing
middle (MidAssign (CmmLocal reg) _) =
text "after", ppr m]) $
Just $ mkMiddles $ [m, spill reg]
else Nothing
+ middle (MidForeignCall _ _ fs _) =
+ case map spill (filter (flip elemRegSet (on_stack live)) fs) ++
+ map reload (uniqSetToList (kill fs (in_regs live))) of
+ [] -> Nothing
+ reloads -> Just (mkMiddles (m : reloads))
middle _ = Nothing
-- Generating spill and reload code
spill r = MidStore (regSlot r) (CmmReg $ CmmLocal r)
reload r = MidAssign (CmmLocal r) (CmmLoad (regSlot r) $ localRegType r)
-spillHead :: ZHead Middle -> RegSet -> ZHead Middle
-reloadTail :: RegSet -> ZTail Middle Last -> ZTail Middle Last
-spillHead h regset = foldl spl h $ uniqSetToList regset
- where spl h r = ZHead h $ spill r
-reloadTail regset t = foldl rel t $ uniqSetToList regset
- where rel t r = ZTail (reload r) t
-
----------------------------------------------------------------
--- sinking reloads
availRegsLattice :: DataflowLattice AvailRegs
availRegsLattice = DataflowLattice "register gotten from reloads" empty add False
- -- last True <==> debugging on
where empty = UniverseMinus emptyRegSet
-- | compute in the Tx monad to track whether anything has changed
add new old =
smallerAvail (AvailRegs s) (AvailRegs s') = sizeUniqSet s < sizeUniqSet s'
smallerAvail (UniverseMinus s) (UniverseMinus s') = sizeUniqSet s > sizeUniqSet s'
---extendAvail :: AvailRegs -> LocalReg -> AvailRegs
---extendAvail (UniverseMinus s) r = UniverseMinus (deleteFromRegSet s r)
---extendAvail (AvailRegs s) r = AvailRegs (extendRegSet s r)
+extendAvail :: AvailRegs -> LocalReg -> AvailRegs
+extendAvail (UniverseMinus s) r = UniverseMinus (deleteFromRegSet s r)
+extendAvail (AvailRegs s) r = AvailRegs (extendRegSet s r)
-deleteFromAvail :: AvailRegs -> LocalReg -> AvailRegs
-deleteFromAvail (UniverseMinus s) r = UniverseMinus (extendRegSet s r)
-deleteFromAvail (AvailRegs s) r = AvailRegs (deleteFromRegSet s r)
+delFromAvail :: AvailRegs -> LocalReg -> AvailRegs
+delFromAvail (UniverseMinus s) r = UniverseMinus (extendRegSet s r)
+delFromAvail (AvailRegs s) r = AvailRegs (deleteFromRegSet s r)
elemAvail :: AvailRegs -> LocalReg -> Bool
elemAvail (UniverseMinus s) r = not $ elemRegSet r s
elemAvail (AvailRegs s) r = elemRegSet r s
-type CmmAvail = BlockEnv AvailRegs
type AvailFix = FuelMonad (ForwardFixedPoint Middle Last AvailRegs ())
-cmmAvailableReloads :: LGraph Middle Last -> FuelMonad CmmAvail
+cmmAvailableReloads :: LGraph Middle Last -> FuelMonad (BlockEnv AvailRegs)
cmmAvailableReloads g = liftM zdfFpFacts $ (res :: AvailFix)
where res = zdfSolveFromL emptyBlockEnv "available reloads" availRegsLattice
avail_reloads_transfer empty g
- empty = (fact_bot availRegsLattice)
+ empty = fact_bot availRegsLattice
avail_reloads_transfer :: ForwardTransfers Middle Last AvailRegs
-avail_reloads_transfer = ForwardTransfers first middle last id
- where first avail _ = avail
- middle = flip middleAvail
- last = lastAvail
-
--- | The transfer equations use the traditional 'gen' and 'kill'
--- notations, which should be familiar from the dragon book.
---agen,
-akill :: UserOfLocalRegs a => a -> AvailRegs -> AvailRegs
---agen a live = foldRegsUsed extendAvail live a
-akill a live = foldRegsUsed deleteFromAvail live a
-
--- Note: you can't sink the reload past a use.
+avail_reloads_transfer = ForwardTransfers (flip const) middleAvail lastAvail id
+
middleAvail :: Middle -> AvailRegs -> AvailRegs
-middleAvail m = middle m
- where middle m live = middle' m $ foldRegsUsed deleteFromAvail live m
- middle' (MidComment {}) = id
- middle' (MidAssign lhs _expr) = akill lhs
- middle' (MidStore {}) = id
- middle' (MidUnsafeCall _tgt ress _args) = akill ress
- middle' (MidAddToContext {}) = id
-
-lastAvail :: AvailRegs -> Last -> LastOutFacts AvailRegs
-lastAvail _ (LastCall _ (Just k) _) = LastOutFacts [(k, AvailRegs emptyRegSet)]
-lastAvail avail l = LastOutFacts $ map (\id -> (id, avail)) $ succs l
-
-insertLateReloads :: LGraph Middle Last -> FuelMonad (LGraph Middle Last)
-insertLateReloads g =
- do env <- cmmAvailableReloads g
- mapM_blocks (insertM env) g
- where insertM env b = fuelConsumingPass "late reloads" (insert b)
- where avail id = lookupBlockEnv env id `orElse` AvailRegs emptyRegSet
- insert (Block id off tail) fuel =
- propagate (ZFirst id off) (avail id) tail fuel
- propagate h avail (ZTail m t) fuel =
- let (h', fuel') = maybe_add_reload h avail m fuel in
- propagate (ZHead h' m) (middleAvail m avail) t fuel'
- propagate h avail (ZLast l) fuel =
- let (h', fuel') = maybe_add_reload h avail l fuel in
- (zipht h' (ZLast l), fuel')
- maybe_add_reload h avail node fuel =
- let used = filterRegsUsed (elemAvail avail) node
- in if not (canRewriteWithFuel fuel) || isEmptyUniqSet used
- then (h,fuel)
- else (spillHead h used, oneLessFuel fuel)
-
-type LateReloadFix = FuelMonad (ForwardFixedPoint Middle Last AvailRegs (LGraph Middle Last))
-
-insertLateReloads' :: (LGraph Middle Last) -> FuelMonad (LGraph Middle Last)
-insertLateReloads' g = liftM zdfFpContents $ (res :: LateReloadFix)
+middleAvail (MidAssign (CmmLocal r) (CmmLoad l _)) avail
+ | l `isStackSlotOf` r = extendAvail avail r
+middleAvail (MidAssign lhs _) avail = foldRegsDefd delFromAvail avail lhs
+middleAvail (MidStore l (CmmReg (CmmLocal r))) avail
+ | l `isStackSlotOf` r = avail
+middleAvail (MidStore (CmmStackSlot (RegSlot r) _) _) avail = delFromAvail avail r
+middleAvail (MidStore {}) avail = avail
+middleAvail (MidForeignCall {}) _ = AvailRegs emptyRegSet
+middleAvail (MidComment {}) avail = avail
+
+lastAvail :: Last -> AvailRegs -> LastOutFacts AvailRegs
+lastAvail (LastCall _ (Just k) _ _ _) _ = LastOutFacts [(k, AvailRegs emptyRegSet)]
+lastAvail l avail = LastOutFacts $ map (\id -> (id, avail)) $ succs l
+
+type LateReloadFix = FuelMonad (ForwardFixedPoint Middle Last AvailRegs CmmGraph)
+
+availRewrites :: ForwardRewrites Middle Last AvailRegs
+availRewrites = ForwardRewrites first middle last exit
+ where first _ _ = Nothing
+ middle m avail = maybe_reload_before avail m (mkMiddle m)
+ last l avail = maybe_reload_before avail l (mkLast l)
+ exit _ = Nothing
+ maybe_reload_before avail node tail =
+ let used = filterRegsUsed (elemAvail avail) node
+ in if isEmptyUniqSet used then Nothing
+ else Just $ reloadTail used tail
+ reloadTail regset t = foldl rel t $ uniqSetToList regset
+ where rel t r = mkMiddle (reload r) <*> t
+
+
+insertLateReloads :: (LGraph Middle Last) -> FuelMonad (LGraph Middle Last)
+insertLateReloads g = liftM zdfFpContents $ (res :: LateReloadFix)
where res = zdfFRewriteFromL RewriteShallow emptyBlockEnv "insert late reloads"
- availRegsLattice avail_reloads_transfer rewrites bot g
+ availRegsLattice avail_reloads_transfer availRewrites bot g
bot = fact_bot availRegsLattice
- rewrites = ForwardRewrites first middle last exit
- first _ _ = Nothing
- middle :: AvailRegs -> Middle -> Maybe (AGraph Middle Last)
- last :: AvailRegs -> Last -> Maybe (AGraph Middle Last)
- middle avail m = maybe_reload_before avail m (ZTail m (ZLast LastExit))
- last avail l = maybe_reload_before avail l (ZLast (LastOther l))
- exit _ = Nothing
- maybe_reload_before avail node tail =
- let used = filterRegsUsed (elemAvail avail) node
- in if isEmptyUniqSet used then Nothing
- else Just $ mkZTail $ reloadTail used tail
removeDeadAssignmentsAndReloads :: BlockSet -> (LGraph Middle Last) -> FuelMonad (LGraph Middle Last)
-removeDeadAssignmentsAndReloads procPoints g =
+removeDeadAssignmentsAndReloads procPoints g@(LGraph entry _) =
liftM zdfFpContents $ (res :: LiveReloadFix (LGraph Middle Last))
where res = zdfBRewriteFromL RewriteDeep emptyBlockEnv "dead-assignment & -reload elim"
- dualLiveLattice (dualLiveTransfers procPoints)
+ dualLiveLattice (dualLiveTransfers entry procPoints)
rewrites (fact_bot dualLiveLattice) g
- rewrites = BackwardRewrites first middle last exit
- exit = Nothing
- last = \_ _ -> Nothing
- middle = middleRemoveDeads
- first _ _ = Nothing
-
-middleRemoveDeads :: DualLive -> Middle -> Maybe (AGraph Middle Last)
-middleRemoveDeads live m = middle m
- where middle (MidAssign (CmmLocal reg') _)
- | not (reg' `elemRegSet` in_regs live) = Just emptyAGraph
- middle _ = Nothing
+ rewrites = BackwardRewrites nothing middleRemoveDeads nothing Nothing
+ nothing _ _ = Nothing
+
+middleRemoveDeads :: Middle -> DualLive -> Maybe (AGraph Middle Last)
+middleRemoveDeads (MidAssign (CmmLocal reg') _) live
+ | not (reg' `elemRegSet` in_regs live) = Just emptyAGraph
+middleRemoveDeads _ _ = Nothing
projects / ghc-hetmet.git / blobdiff