+{-# OPTIONS_GHC -XNoMonoLocalBinds #-}
+-- Norman likes local bindings
+-- If this module lives on I'd like to get rid of this flag in due course
module CmmCPSZ (
-- | Converts C-- with full proceedures and parameters
protoCmmCPSZ
) where
+import CLabel
import Cmm
-import CmmContFlowOpt
+import CmmBuildInfoTables
+import CmmCommonBlockElimZ
import CmmProcPointZ
import CmmSpillReload
-import CmmTx
+import CmmStackLayout
import DFMonad
+import PprCmmZ()
+import ZipCfgCmmRep
+
import DynFlags
import ErrUtils
+import HscTypes
+import Data.Maybe
+import Control.Monad
+import Data.Map (Map)
+import qualified Data.Map as Map
import Outputable
-import PprCmmZ()
-import UniqSupply
-import ZipCfg hiding (zip, unzip)
-import ZipCfgCmmRep
-import ZipDataflow
+import StaticFlags
-----------------------------------------------------------------------------
-- |Top level driver for the CPS pass
-----------------------------------------------------------------------------
-protoCmmCPSZ :: DynFlags -- ^ Dynamic flags: -dcmm-lint -ddump-cps-cmm
- -> CmmZ -- ^ Input C-- with Proceedures
- -> IO CmmZ -- ^ Output CPS transformed C--
-protoCmmCPSZ dflags (Cmm tops)
- = do { showPass dflags "CPSZ"
- ; u <- mkSplitUniqSupply 'p'
- ; let txtops = initUs_ u $ mapM cpsTop tops
- ; let pgm = Cmm $ runDFTx maxBound $ sequence txtops
- --- XXX calling runDFTx is totally bogus
- ; dumpIfSet_dyn dflags Opt_D_dump_cps_cmm "CPS Cmm" (ppr pgm)
- ; return pgm
- }
-
-cpsTop :: CmmTopZ -> UniqSM (DFTx CmmTopZ)
-cpsTop p@(CmmData {}) = return $ return p
-cpsTop (CmmProc h l args g) =
- let procPoints = minimalProcPointSet (runTx cmmCfgOptsZ g)
- g' = addProcPointProtocols procPoints args g
- g'' = map_nodes id NotSpillOrReload id g'
- in do us <- getUs
- let g = runDFM us dualLiveLattice $ b_rewrite dualLivenessWithInsertion g''
- -- let igraph = buildIGraph
- return $ do g' <- g >>= return . map_nodes id spillAndReloadComments id
- return $ CmmProc h l args g'
+-- There are two complications here:
+-- 1. We need to compile the procedures in two stages because we need
+-- an analysis of the procedures to tell us what CAFs they use.
+-- The first stage returns a map from procedure labels to CAFs,
+-- along with a closure that will compute SRTs and attach them to
+-- the compiled procedures.
+-- The second stage is to combine the CAF information into a top-level
+-- CAF environment mapping non-static closures to the CAFs they keep live,
+-- then pass that environment to the closures returned in the first
+-- stage of compilation.
+-- 2. We need to thread the module's SRT around when the SRT tables
+-- are computed for each procedure.
+-- The SRT needs to be threaded because it is grown lazily.
+protoCmmCPSZ :: HscEnv -- Compilation env including
+ -- dynamic flags: -dcmm-lint -ddump-cps-cmm
+ -> (TopSRT, [CmmZ]) -- SRT table and accumulating list of compiled procs
+ -> CmmZ -- Input C-- with Procedures
+ -> IO (TopSRT, [CmmZ]) -- Output CPS transformed C--
+protoCmmCPSZ hsc_env (topSRT, rst) (Cmm tops) =
+ do let dflags = hsc_dflags hsc_env
+ showPass dflags "CPSZ"
+ (cafEnvs, tops) <- liftM unzip $ mapM (cpsTop hsc_env) tops
+ let topCAFEnv = mkTopCAFInfo (concat cafEnvs)
+ (topSRT, tops) <- foldM (toTops hsc_env topCAFEnv) (topSRT, []) tops
+ -- (topSRT, tops) <- foldM (\ z f -> f topCAFEnv z) (topSRT, []) toTops
+ let cmms = Cmm (reverse (concat tops))
+ dumpIfSet_dyn dflags Opt_D_dump_cps_cmm "Post CPS Cmm" (ppr cmms)
+ return (topSRT, cmms : rst)
+
+{- [Note global fuel]
+~~~~~~~~~~~~~~~~~~~~~
+The identity and the last pass are stored in
+mutable reference cells in an 'HscEnv' and are
+global to one compiler session.
+-}
+
+cpsTop :: HscEnv -> CmmTopZ ->
+ IO ([(CLabel, CAFSet)],
+ [(CAFSet, CmmTopForInfoTables)])
+cpsTop _ p@(CmmData {}) = return ([], [(Map.empty, NoInfoTable p)])
+cpsTop hsc_env (CmmProc h l args (stackInfo@(entry_off, _), g)) =
+ do
+ dump Opt_D_dump_cmmz "Pre Proc Points Added" g
+ let callPPs = callProcPoints g
+ -- Why bother doing it this early?
+ -- g <- dual_rewrite Opt_D_dump_cmmz "spills and reloads"
+ -- (dualLivenessWithInsertion callPPs) g
+ -- g <- run $ insertLateReloads g -- Duplicate reloads just before uses
+ -- g <- dual_rewrite Opt_D_dump_cmmz "Dead Assignment Elimination"
+ -- (removeDeadAssignmentsAndReloads callPPs) g
+ dump Opt_D_dump_cmmz "Pre common block elimination" g
+ g <- return $ elimCommonBlocks g
+ dump Opt_D_dump_cmmz "Post common block elimination" g
+
+ ----------- Proc points -------------------
+ procPoints <- run $ minimalProcPointSet callPPs g
+ g <- run $ addProcPointProtocols callPPs procPoints g
+ dump Opt_D_dump_cmmz "Post Proc Points Added" g
+
+ ----------- Spills and reloads -------------------
+ g <-
+ -- pprTrace "pre Spills" (ppr g) $
+ dual_rewrite Opt_D_dump_cmmz "spills and reloads"
+ (dualLivenessWithInsertion procPoints) g
+ -- Insert spills at defns; reloads at return points
+ g <-
+ -- pprTrace "pre insertLateReloads" (ppr g) $
+ run $ insertLateReloads g -- Duplicate reloads just before uses
+ dump Opt_D_dump_cmmz "Post late reloads" g
+ g <-
+ -- pprTrace "post insertLateReloads" (ppr g) $
+ dual_rewrite Opt_D_dump_cmmz "Dead Assignment Elimination"
+ (removeDeadAssignmentsAndReloads procPoints) g
+ -- Remove redundant reloads (and any other redundant asst)
+
+ ----------- Debug only: add code to put zero in dead stack slots----
+ -- Debugging: stubbing slots on death can cause crashes early
+ g <-
+ -- trace "post dead-assign elim" $
+ if opt_StubDeadValues then run $ stubSlotsOnDeath g else return g
+
+
+ --------------- Stack layout ----------------
+ slotEnv <- run $ liveSlotAnal g
+ mbpprTrace "live slot analysis results: " (ppr slotEnv) $ return ()
+ -- cafEnv <- -- trace "post liveSlotAnal" $ run $ cafAnal g
+ -- (cafEnv, slotEnv) <-
+ -- -- trace "post print cafAnal" $
+ -- return $ extendEnvsForSafeForeignCalls cafEnv slotEnv g
+ slotEnv <- return $ extendEnvWithSafeForeignCalls liveSlotTransfers slotEnv g
+ mbpprTrace "slotEnv extended for safe foreign calls: " (ppr slotEnv) $ return ()
+ let areaMap = layout procPoints slotEnv entry_off g
+ mbpprTrace "areaMap" (ppr areaMap) $ return ()
+
+ ------------ Manifest the the stack pointer --------
+ g <- run $ manifestSP areaMap entry_off g
+ dump Opt_D_dump_cmmz "after manifestSP" g
+ -- UGH... manifestSP can require updates to the procPointMap.
+ -- We can probably do something quicker here for the update...
+
+ ------------- Split into separate procedures ------------
+ procPointMap <- run $ procPointAnalysis procPoints g
+ dump Opt_D_dump_cmmz "procpoint map" procPointMap
+ gs <- run $ splitAtProcPoints l callPPs procPoints procPointMap
+ (CmmProc h l args (stackInfo, g))
+ mapM_ (dump Opt_D_dump_cmmz "after splitting") gs
+
+ ------------- More CAFs and foreign calls ------------
+ cafEnv <- run $ cafAnal g
+ cafEnv <- return $ extendEnvWithSafeForeignCalls cafTransfers cafEnv g
+ let localCAFs = catMaybes $ map (localCAFInfo cafEnv) gs
+ mbpprTrace "localCAFs" (ppr localCAFs) $ return ()
+
+ gs <- liftM concat $ run $ foldM lowerSafeForeignCalls [] gs
+ mapM_ (dump Opt_D_dump_cmmz "after lowerSafeForeignCalls") gs
+
+ -- NO MORE GRAPH TRANSFORMATION AFTER HERE -- JUST MAKING INFOTABLES
+ let gs' = map (setInfoTableStackMap slotEnv areaMap) gs
+ mapM_ (dump Opt_D_dump_cmmz "after setInfoTableStackMap") gs'
+ let gs'' = map (bundleCAFs cafEnv) gs'
+ mapM_ (dump Opt_D_dump_cmmz "after bundleCAFs") gs''
+ return (localCAFs, gs'')
+ where dflags = hsc_dflags hsc_env
+ mbpprTrace x y z = if dopt Opt_D_dump_cmmz dflags then pprTrace x y z else z
+ dump f txt g = dumpIfSet_dyn dflags f txt (ppr g)
+
+ run :: FuelMonad a -> IO a
+ run = runFuelIO (hsc_OptFuel hsc_env)
+
+ dual_rewrite flag txt pass g =
+ do dump flag ("Pre " ++ txt) g
+ g <- run $ pass g
+ dump flag ("Post " ++ txt) $ g
+ return g
+
+-- This probably belongs in CmmBuildInfoTables?
+-- We're just finishing the job here: once we know what CAFs are defined
+-- in non-static closures, we can build the SRTs.
+toTops :: HscEnv -> Map CLabel CAFSet -> (TopSRT, [[CmmTopZ]])
+ -> [(CAFSet, CmmTopForInfoTables)] -> IO (TopSRT, [[CmmTopZ]])
+
+toTops hsc_env topCAFEnv (topSRT, tops) gs =
+ do let setSRT (topSRT, rst) g =
+ do (topSRT, gs) <- setInfoTableSRT topCAFEnv topSRT g
+ return (topSRT, gs : rst)
+ (topSRT, gs') <- runFuelIO (hsc_OptFuel hsc_env) $ foldM setSRT (topSRT, []) gs
+ gs' <- mapM finishInfoTables (concat gs')
+ return (topSRT, concat gs' : tops)