+{-# LANGUAGE GADTs,NoMonoLocalBinds #-}
+-- Norman likes local bindings
+-- If this module lives on I'd like to get rid of this flag in due course
+
+{-# OPTIONS_GHC -fno-warn-incomplete-patterns #-}
+#if __GLASGOW_HASKELL__ >= 701
+-- GHC 7.0.1 improved incomplete pattern warnings with GADTs
+{-# OPTIONS_GHC -fwarn-incomplete-patterns #-}
+#endif
module CmmSpillReload
- ( ExtendWithSpills(..)
- , DualLive(..)
- , dualLiveLattice, dualLiveness
- , insertSpillsAndReloads --- XXX todo check live-in at entry against formals
+ ( DualLive(..)
+ , dualLiveLattice, dualLiveTransfers, dualLiveness
+ --, insertSpillsAndReloads --- XXX todo check live-in at entry against formals
, dualLivenessWithInsertion
- , spillAndReloadComments
, availRegsLattice
, cmmAvailableReloads
)
where
+import BlockId
+import Cmm
import CmmExpr
-import CmmTx
-import CmmLiveZ
-import DFMonad
-import MkZipCfg
-import PprCmm()
-import ZipCfg
-import ZipCfgCmmRep
-import ZipDataflow
-
-import FastString
-import Maybes
+import CmmLive
+import OptimizationFuel
+
+import Control.Monad
import Outputable hiding (empty)
import qualified Outputable as PP
-import Panic
import UniqSet
-import Maybe
-import Prelude hiding (zip)
-
--- The point of this module is to insert spills and reloads to
--- establish the invariant that at a call (or at any proc point with
--- an established protocol) all live variables not expected in
--- registers are sitting on the stack. We use a backward analysis to
--- insert spills and reloads. It should some day be followed by a
--- forward transformation to sink reloads as deeply as possible, so as
--- to reduce register pressure.
-
-data ExtendWithSpills m
- = NotSpillOrReload m
- | Spill RegSet
- | Reload RegSet
-
-type M = ExtendWithSpills Middle
-
--- A variable can be expected to be live in a register, live on the
--- stack, or both. This analysis ensures that spills and reloads are
--- inserted as needed to make sure that every live variable needed
--- after a call is available on the stack. Spills are pushed back to
--- their reaching definitions, but reloads are dropped wherever needed
--- and will have to be sunk by a later forward transformation.
+import Compiler.Hoopl
+import Data.Maybe
+import Prelude hiding (succ, zip)
+
+{- Note [Overview of spill/reload]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+The point of this module is to insert spills and reloads to
+establish the invariant that at a call (or at any proc point with
+an established protocol) all live variables not expected in
+registers are sitting on the stack. We use a backward analysis to
+insert spills and reloads. It should be followed by a
+forward transformation to sink reloads as deeply as possible, so as
+to reduce register pressure.
+
+A variable can be expected to be live in a register, live on the
+stack, or both. This analysis ensures that spills and reloads are
+inserted as needed to make sure that every live variable needed
+after a call is available on the stack. Spills are pushed back to
+their reaching definitions, but reloads are dropped wherever needed
+and will have to be sunk by a later forward transformation.
+-}
data DualLive = DualLive { on_stack :: RegSet, in_regs :: RegSet }
where ss = unionManyUniqSets $ map on_stack ls
rs = unionManyUniqSets $ map in_regs ls
-_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) }
+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) }
dualLiveLattice :: DataflowLattice DualLive
-dualLiveLattice =
- DataflowLattice "variables live in registers and on stack" empty add False
+dualLiveLattice = DataflowLattice "variables live in registers and on stack" empty add
where empty = DualLive emptyRegSet emptyRegSet
- -- | compute in the Tx monad to track whether anything has changed
- add new old = do stack <- add1 (on_stack new) (on_stack old)
- regs <- add1 (in_regs new) (in_regs old)
- return $ DualLive stack regs
- add1 = fact_add_to liveLattice
-
-dualLivenessWithInsertion :: BPass M Last DualLive
-dualLivenessWithInsertion = a_ft_b_unlimited dualLiveness insertSpillsAndReloads
-
-dualLiveness :: BAnalysis M Last DualLive
-dualLiveness = BComp "dual liveness" exit last middle first
- where exit = empty
- last = lastDualLiveness
- middle = middleDualLiveness
- first live _id = live
- empty = fact_bot dualLiveLattice
-
- -- ^ could take a proc-point set and choose to spill here,
- -- but it's probably better to run this pass, choose
- -- proc-point protocols, insert more CopyIn nodes, and run
- -- this pass again
-
-middleDualLiveness :: DualLive -> M -> DualLive
-middleDualLiveness live (Spill regs) = live'
- -- live-in on-stack requirements are satisfied;
- -- live-out in-regs obligations are created
- where live' = DualLive { on_stack = on_stack live `minusRegSet` regs
- , in_regs = in_regs live `plusRegSet` regs }
-
-middleDualLiveness live (Reload regs) = live'
- -- live-in in-regs requirements are satisfied;
- -- live-out on-stack obligations are created
- where live' = DualLive { on_stack = on_stack live `plusRegSet` regs
- , in_regs = in_regs live `minusRegSet` regs }
-
-middleDualLiveness live (NotSpillOrReload m) = changeRegs (middleLiveness m) live
-
-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
- 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 $
- map env (catMaybes tbl)
- empty = fact_bot dualLiveLattice
-
-gen, kill :: UserOfLocalRegs a => a -> RegSet -> RegSet
-gen a live = foldRegsUsed extendRegSet live a
-kill a live = foldRegsUsed delOneFromUniqSet live a
-
-insertSpillsAndReloads :: BFunctionalTransformation M Last DualLive
-insertSpillsAndReloads = BComp "CPS spiller" exit last middle first
- where exit = Nothing
- last = \_ _ -> Nothing
- middle = middleInsertSpillsAndReloads
- first _ _ = Nothing
- -- ^ could take a proc-point set and choose to spill here,
- -- but it's probably better to run this pass, choose
- -- proc-point protocols, insert more CopyIn nodes, and run
- -- this pass again
-
-
-middleInsertSpillsAndReloads :: DualLive -> M -> Maybe (Graph M Last)
-middleInsertSpillsAndReloads _ (Spill _) = Nothing
-middleInsertSpillsAndReloads _ (Reload _) = Nothing
-middleInsertSpillsAndReloads live (NotSpillOrReload m) = middle m
- where middle (MidAssign (CmmLocal reg') _) =
- if reg' `elemRegSet` on_stack live then -- must spill
- my_trace "Spilling" (f4sep [text "spill" <+> ppr reg',
- text "after", ppr m]) $
- Just $ graphOfMiddles [NotSpillOrReload m, Spill $ mkRegSet [reg']]
- else
- Nothing
- middle (CopyIn _ formals _) =
- -- only 'formals' can be in regs at this point
- let regs' = kill formals (in_regs live) -- live in regs; must reload
- is_stack_var r = elemRegSet r (on_stack live)
- needs_spilling = -- a formal that is expected on the stack; must spill
- foldRegsUsed (\rs r -> if is_stack_var r then extendRegSet rs r
- else rs) emptyRegSet formals
- in if isEmptyUniqSet regs' && isEmptyUniqSet needs_spilling then
- Nothing
- else
- let reload = if isEmptyUniqSet regs' then []
- else [Reload regs']
- spill_reload = if isEmptyUniqSet needs_spilling then reload
- else Spill needs_spilling : reload
- middles = NotSpillOrReload m : spill_reload
- in
- my_trace "At CopyIn" (f4sep [text "Triggered by ", ppr live,
- ppr (Reload regs' :: M),
- ppr (Spill needs_spilling :: M),
- text "after", ppr m]) $
- Just $ graphOfMiddles middles
- middle _ = Nothing
-
--- | For conversion back to vanilla C--
-spillAndReloadComments :: M -> Middle
-spillAndReloadComments (NotSpillOrReload m) = m
-spillAndReloadComments (Spill regs) = show_regs "Spill" regs
-spillAndReloadComments (Reload regs) = show_regs "Reload" regs
-
-show_regs :: String -> RegSet -> Middle
-show_regs s regs = MidComment $ mkFastString $ showSDoc $ ppr_regs s regs
-
+ add _ (OldFact old) (NewFact new) = (changeIf $ change1 || change2, DualLive stack regs)
+ where (change1, stack) = add1 (on_stack old) (on_stack new)
+ (change2, regs) = add1 (in_regs old) (in_regs new)
+ add1 old new = if sizeUniqSet join > sizeUniqSet old then (True, join) else (False, old)
+ where join = unionUniqSets old new
+
+dualLivenessWithInsertion :: BlockSet -> CmmGraph -> FuelUniqSM CmmGraph
+dualLivenessWithInsertion procPoints g =
+ liftM fst $ dataflowPassBwd g [] $ analRewBwd dualLiveLattice
+ (dualLiveTransfers (g_entry g) procPoints)
+ (insertSpillAndReloadRewrites g procPoints)
+
+dualLiveness :: BlockSet -> CmmGraph -> FuelUniqSM (BlockEnv DualLive)
+dualLiveness procPoints g =
+ liftM snd $ dataflowPassBwd g [] $ analBwd dualLiveLattice $ dualLiveTransfers (g_entry g) procPoints
+
+dualLiveTransfers :: BlockId -> BlockSet -> (BwdTransfer CmmNode DualLive)
+dualLiveTransfers entry procPoints = mkBTransfer3 first middle last
+ where first :: CmmNode C O -> DualLive -> DualLive
+ first (CmmEntry id) live = check live id $ -- live at procPoint => spill
+ if id /= entry && setMember id procPoints
+ then DualLive { on_stack = on_stack live `plusRegSet` in_regs live
+ , in_regs = emptyRegSet }
+ else live
+ where check live id x = if id == entry then noLiveOnEntry id (in_regs live) x else x
+
+ middle :: CmmNode O O -> DualLive -> DualLive
+ middle m = changeStack updSlots
+ . changeRegs updRegs
+ where -- Reuse middle of liveness analysis from CmmLive
+ updRegs = case getBTransfer3 xferLive of (_, middle, _) -> middle m
+
+ 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
+ reload live _ = live
+ check (RegSlot (LocalReg _ ty), o, w) x
+ | o == w && w == widthInBytes (typeWidth ty) = x
+ check _ _ = panic "middleDualLiveness unsupported: slices"
+ last :: CmmNode O C -> FactBase DualLive -> DualLive
+ last l fb = case l of
+ CmmBranch id -> lkp id
+ l@(CmmCall {cml_cont=Nothing}) -> changeRegs (gen l . kill l) empty
+ l@(CmmCall {cml_cont=Just k}) -> call l k
+ l@(CmmForeignCall {succ=k}) -> call l k
+ l@(CmmCondBranch _ t f) -> changeRegs (gen l . kill l) $ dualUnion (lkp t) (lkp f)
+ l@(CmmSwitch _ tbl) -> changeRegs (gen l . kill l) $ dualUnionList $ map lkp (catMaybes tbl)
+ where empty = fact_bot dualLiveLattice
+ lkp id = empty `fromMaybe` lookupFact id fb
+ call l k = DualLive (on_stack (lkp k)) (gen l emptyRegSet)
+
+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 :: CmmGraph -> BlockSet -> CmmBwdRewrite DualLive
+insertSpillAndReloadRewrites graph procPoints = deepBwdRw3 first middle nothing
+ -- Beware: deepBwdRw with one polymorphic function seems more reasonable here,
+ -- but GHC miscompiles it, see bug #4044.
+ where first :: CmmNode C O -> Fact O DualLive -> CmmReplGraph C O
+ first e@(CmmEntry id) live = return $
+ if id /= (g_entry graph) && setMember id procPoints then
+ case map reload (uniqSetToList spill_regs) of
+ [] -> Nothing
+ is -> Just $ mkFirst e <*> mkMiddles is
+ else Nothing
+ where
+ -- If we are splitting procedures, we need the LastForeignCall
+ -- to spill its results to the stack because they will only
+ -- be used by a separate procedure (so they can't stay in LocalRegs).
+ splitting = True
+ spill_regs = if splitting then in_regs live
+ else in_regs live `minusRegSet` defs
+ defs = case mapLookup id firstDefs of
+ Just defs -> defs
+ Nothing -> emptyRegSet
+ -- A LastForeignCall may contain some definitions, which take place
+ -- on return from the function call. Therefore, we build a map (firstDefs)
+ -- from BlockId to the set of variables defined on return to the BlockId.
+ firstDefs = mapFold addLive emptyBlockMap (toBlockMap graph)
+ addLive :: CmmBlock -> BlockEnv RegSet -> BlockEnv RegSet
+ addLive b env = case lastNode b of
+ CmmForeignCall {succ=k, res=defs} -> add k (mkRegSet defs) env
+ _ -> env
+ add bid defs env = mapInsert bid defs'' env
+ where defs'' = case mapLookup bid env of
+ Just defs' -> timesRegSet defs defs'
+ Nothing -> defs
+
+ middle :: CmmNode O O -> Fact O DualLive -> CmmReplGraph O O
+ middle (CmmAssign (CmmLocal reg) (CmmLoad (CmmStackSlot (RegSlot reg') _) _)) _ | reg == reg' = return Nothing
+ middle m@(CmmAssign (CmmLocal reg) _) live = return $
+ if reg `elemRegSet` on_stack live then -- must spill
+ my_trace "Spilling" (f4sep [text "spill" <+> ppr reg,
+ text "after"{-, ppr m-}]) $
+ Just $ mkMiddles $ [m, spill reg]
+ else Nothing
+ middle m@(CmmUnsafeForeignCall _ fs _) live = return $
+ 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 _ _ = return Nothing
+
+ nothing _ _ = return Nothing
+
+regSlot :: LocalReg -> CmmExpr
+regSlot r = CmmStackSlot (RegSlot r) (widthInBytes $ typeWidth $ localRegType r)
+
+spill, reload :: LocalReg -> CmmNode O O
+spill r = CmmStore (regSlot r) (CmmReg $ CmmLocal r)
+reload r = CmmAssign (CmmLocal r) (CmmLoad (regSlot r) $ localRegType r)
----------------------------------------------------------------
--- sinking reloads
availRegsLattice :: DataflowLattice AvailRegs
-availRegsLattice = DataflowLattice "register gotten from reloads" empty add True
+availRegsLattice = DataflowLattice "register gotten from reloads" empty add
where empty = UniverseMinus emptyRegSet
-- | compute in the Tx monad to track whether anything has changed
- add new old =
- let join = interAvail new old in
- if join `smallerAvail` old then aTx join else noTx join
+ add _ (OldFact old) (NewFact new) =
+ if join `smallerAvail` old then (SomeChange, join) else (NoChange, old)
+ where join = interAvail new old
interAvail :: AvailRegs -> AvailRegs -> 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
-cmmAvailableReloads :: LGraph M Last -> BlockEnv AvailRegs
-cmmAvailableReloads g = env
- where env = runDFA availRegsLattice $
- do run_f_anal transfer (fact_bot availRegsLattice) g
- allFacts
- transfer :: FAnalysis M Last AvailRegs
- transfer = FComp "available-reloads analysis" first middle last exit
- exit _ = LastOutFacts []
- 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
-
-middleAvail :: M -> AvailRegs -> AvailRegs
-middleAvail (Spill _) = id
-middleAvail (Reload regs) = agen regs
-middleAvail (NotSpillOrReload m) = middle m
- where middle (MidComment {}) = id
- middle (MidAssign lhs _expr) = akill lhs
- middle (MidStore {}) = id
- middle (MidUnsafeCall _tgt ress _args) = akill ress
- middle (CopyIn _ formals _) = akill formals
- middle (CopyOut {}) = 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 M Last -> DFTx (LGraph M Last)
-insertLateReloads g = mapM_blocks insertM g
- where env = cmmAvailableReloads g
- avail id = lookupBlockEnv env id `orElse` AvailRegs emptyRegSet
- insertM b = functionalDFTx "late reloads" (insert b)
- insert (Block id tail) fuel = propagate (ZFirst id) (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 = foldRegsUsed
- (\u r -> if elemAvail avail r then extendRegSet u r else u)
- emptyRegSet node
- in if fuel == 0 || isEmptyUniqSet used then (h, fuel)
- else (ZHead h (Reload used), fuel-1)
-
-
-removeDeadAssignmentsAndReloads :: BPass M Last DualLive
-removeDeadAssignmentsAndReloads = a_ft_b dualLiveness remove_deads
- where remove_deads = BComp "dead-assignment & -reload elim" exit last middle first
- exit = Nothing
- last = \_ _ -> Nothing
- middle = middleRemoveDeads
- first _ _ = Nothing
-
-middleRemoveDeads :: DualLive -> M -> Maybe (Graph M Last)
-middleRemoveDeads _ (Spill _) = Nothing
-middleRemoveDeads live (Reload s) =
- if sizeUniqSet worth_reloading < sizeUniqSet s then
- Just $ if isEmptyUniqSet worth_reloading then emptyGraph
- else graphOfMiddles [Reload worth_reloading]
- else
- Nothing
- where worth_reloading = intersectUniqSets s (in_regs live)
-middleRemoveDeads live (NotSpillOrReload m) = middle m
- where middle (MidAssign (CmmLocal reg') _)
- | not (reg' `elemRegSet` in_regs live) = Just emptyGraph
- middle _ = Nothing
-
-
-
----------------------
--- register usage
+cmmAvailableReloads :: CmmGraph -> FuelUniqSM (BlockEnv AvailRegs)
+cmmAvailableReloads g =
+ liftM snd $ dataflowPassFwd g [(g_entry g, fact_bot availRegsLattice)] $
+ analFwd availRegsLattice availReloadsTransfer
+
+availReloadsTransfer :: FwdTransfer CmmNode AvailRegs
+availReloadsTransfer = mkFTransfer3 (flip const) middleAvail ((mkFactBase availRegsLattice .) . lastAvail)
+
+middleAvail :: CmmNode O O -> AvailRegs -> AvailRegs
+middleAvail (CmmAssign (CmmLocal r) (CmmLoad l _)) avail
+ | l `isStackSlotOf` r = extendAvail avail r
+middleAvail (CmmAssign lhs _) avail = foldRegsDefd delFromAvail avail lhs
+middleAvail (CmmStore l (CmmReg (CmmLocal r))) avail
+ | l `isStackSlotOf` r = avail
+middleAvail (CmmStore (CmmStackSlot (RegSlot r) _) _) avail = delFromAvail avail r
+middleAvail (CmmStore {}) avail = avail
+middleAvail (CmmUnsafeForeignCall {}) _ = AvailRegs emptyRegSet
+middleAvail (CmmComment {}) avail = avail
+
+lastAvail :: CmmNode O C -> AvailRegs -> [(Label, AvailRegs)]
+lastAvail (CmmCall _ (Just k) _ _ _) _ = [(k, AvailRegs emptyRegSet)]
+lastAvail (CmmForeignCall {succ=k}) _ = [(k, AvailRegs emptyRegSet)]
+lastAvail l avail = map (\id -> (id, avail)) $ successors l
+
+insertLateReloads :: CmmGraph -> FuelUniqSM CmmGraph
+insertLateReloads g =
+ liftM fst $ dataflowPassFwd g [(g_entry g, fact_bot availRegsLattice)] $
+ analRewFwd availRegsLattice availReloadsTransfer rewrites
+ where rewrites = mkFRewrite3 first middle last
+ first _ _ = return Nothing
+ middle m avail = return $ maybe_reload_before avail m (mkMiddle m)
+ last l avail = return $ maybe_reload_before avail l (mkLast l)
+ 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
+
+removeDeadAssignmentsAndReloads :: BlockSet -> CmmGraph -> FuelUniqSM CmmGraph
+removeDeadAssignmentsAndReloads procPoints g =
+ liftM fst $ dataflowPassBwd g [] $ analRewBwd dualLiveLattice
+ (dualLiveTransfers (g_entry g) procPoints)
+ rewrites
+ where rewrites = deepBwdRw3 nothing middle nothing
+ -- Beware: deepBwdRw with one polymorphic function seems more reasonable here,
+ -- but GHC panics while compiling, see bug #4045.
+ middle :: CmmNode O O -> Fact O DualLive -> CmmReplGraph O O
+ middle (CmmAssign (CmmLocal reg') _) live | not (reg' `elemRegSet` in_regs live) = return $ Just emptyGraph
+ middle _ _ = return Nothing
+
+ nothing _ _ = return Nothing
-instance UserOfLocalRegs m => UserOfLocalRegs (ExtendWithSpills m) where
- foldRegsUsed f z (Spill regs) = foldRegsUsed f z regs
- foldRegsUsed _f z (Reload _) = z
- foldRegsUsed f z (NotSpillOrReload m) = foldRegsUsed f z m
---------------------
-- prettyprinting
-instance Outputable m => Outputable (ExtendWithSpills m) where
- ppr (Spill regs) = ppr_regs "Spill" regs
- ppr (Reload regs) = ppr_regs "Reload" regs
- ppr (NotSpillOrReload m) = ppr m
-
-instance Outputable (LGraph M Last) where
- ppr = pprLgraph
-
-instance DebugNodes M Last
-
ppr_regs :: String -> RegSet -> SDoc
ppr_regs s regs = text s <+> commafy (map ppr $ uniqSetToList regs)
where commafy xs = hsep $ punctuate comma xs