-applyContinuationFormat :: [(CLabel, ContinuationFormat)]
- -> Continuation (Either C_SRT CmmInfo)
- -> Continuation CmmInfo
-
--- User written continuations
-applyContinuationFormat formats (Continuation
- (Right (CmmInfo gc update_frame (CmmInfoTable prof tag (ContInfo _ srt))))
- label formals is_gc blocks) =
- Continuation (CmmInfo gc update_frame (CmmInfoTable prof tag (ContInfo format srt)))
- label formals is_gc blocks
- where
- format = continuation_stack $ maybe unknown_block id $ lookup label formats
- unknown_block = panic "unknown BlockId in applyContinuationFormat"
-
--- Either user written non-continuation code or CPS generated proc-point
-applyContinuationFormat formats (Continuation
- (Right info) label formals is_gc blocks) =
- Continuation info label formals is_gc blocks
-
--- CPS generated continuations
-applyContinuationFormat formats (Continuation
- (Left srt) label formals is_gc blocks) =
- Continuation (CmmInfo gc Nothing (CmmInfoTable prof tag (ContInfo (continuation_stack $ format) srt)))
- label formals is_gc blocks
- where
- gc = Nothing -- Generated continuations never need a stack check
- -- TODO prof: this is the same as the current implementation
- -- but I think it could be improved
- prof = ProfilingInfo zeroCLit zeroCLit
- tag = rET_SMALL -- cmmToRawCmm may convert it to rET_BIG
- format = maybe unknown_block id $ lookup label formats
- unknown_block = panic "unknown BlockId in applyContinuationFormat"
-
+-- 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.
+-- 3. We run control flow optimizations twice, once before any pipeline
+-- work is done, and once again at the very end on all of the
+-- resulting C-- blocks. EZY: It's unclear whether or not whether
+-- we actually need to do the initial pass.
+cmmPipeline :: HscEnv -- Compilation env including
+ -- dynamic flags: -dcmm-lint -ddump-cps-cmm
+ -> (TopSRT, [Cmm]) -- SRT table and accumulating list of compiled procs
+ -> Cmm -- Input C-- with Procedures
+ -> IO (TopSRT, [Cmm]) -- Output CPS transformed C--
+cmmPipeline hsc_env (topSRT, rst) prog =
+ do let dflags = hsc_dflags hsc_env
+ (Cmm tops) = runCmmContFlowOpts prog
+ 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
+ let cmms = Cmm (reverse (concat tops))
+ dumpIfSet_dyn dflags Opt_D_dump_cps_cmm "Post CPS Cmm" (ppr cmms)
+ -- SRT is not affected by control flow optimization pass
+ let prog' = map runCmmContFlowOpts (cmms : rst)
+ return (topSRT, prog')
+
+{- [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.
+-}
+
+-- EZY: It might be helpful to have an easy way of dumping the "pre"
+-- input for any given phase, besides just turning it all on with
+-- -ddump-cmmz
+
+cpsTop :: HscEnv -> CmmTop -> IO ([(CLabel, CAFSet)], [(CAFSet, CmmTop)])
+cpsTop _ p@(CmmData {}) = return ([], [(Map.empty, p)])
+cpsTop hsc_env (CmmProc h@(TopInfo {stack_info=StackInfo {arg_space=entry_off}}) l g) =
+ do
+ -- Why bother doing these early: dualLivenessWithInsertion,
+ -- insertLateReloads, rewriteAssignments?
+
+ ----------- Eliminate common blocks -------------------
+ g <- return $ elimCommonBlocks g
+ dump Opt_D_dump_cmmz_cbe "Post common block elimination" g
+ -- Any work storing block Labels must be performed _after_ elimCommonBlocks
+
+ ----------- Proc points -------------------
+ let callPPs = callProcPoints g
+ procPoints <- run $ minimalProcPointSet callPPs g
+ g <- run $ addProcPointProtocols callPPs procPoints g
+ dump Opt_D_dump_cmmz_proc "Post Proc Points Added" g
+
+ ----------- Spills and reloads -------------------
+ g <- run $ dualLivenessWithInsertion procPoints g
+ dump Opt_D_dump_cmmz_spills "Post spills and reloads" g
+
+ ----------- Sink and inline assignments -------------------
+ g <- runOptimization $ rewriteAssignments g
+ dump Opt_D_dump_cmmz_rewrite "Post rewrite assignments" g
+
+ ----------- Eliminate dead assignments -------------------
+ -- Remove redundant reloads (and any other redundant asst)
+ g <- runOptimization $ removeDeadAssignmentsAndReloads procPoints g
+ dump Opt_D_dump_cmmz_dead "Post Dead Assignment Elimination" g
+
+ ----------- Zero dead stack slots (Debug only) ---------------
+ -- Debugging: stubbing slots on death can cause crashes early
+ g <- if opt_StubDeadValues
+ then run $ stubSlotsOnDeath g
+ else return g
+ dump Opt_D_dump_cmmz_stub "Post stub dead stack slots" g
+
+ --------------- Stack layout ----------------
+ slotEnv <- run $ liveSlotAnal g
+ let spEntryMap = getSpEntryMap entry_off g
+ mbpprTrace "live slot analysis results: " (ppr slotEnv) $ return ()
+ let areaMap = layout procPoints spEntryMap slotEnv entry_off g
+ mbpprTrace "areaMap" (ppr areaMap) $ return ()
+
+ ------------ Manifest the stack pointer --------
+ g <- run $ manifestSP spEntryMap areaMap entry_off g
+ dump Opt_D_dump_cmmz_sp "Post 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_procmap "procpoint map" procPointMap
+ gs <- run $ splitAtProcPoints l callPPs procPoints procPointMap
+ (CmmProc h l g)
+ mapM_ (dump Opt_D_dump_cmmz_split "Post splitting") gs
+
+ ------------- More CAFs and foreign calls ------------
+ cafEnv <- run $ cafAnal g
+ let localCAFs = catMaybes $ map (localCAFInfo cafEnv) gs
+ mbpprTrace "localCAFs" (ppr localCAFs) $ return ()
+
+ gs <- run $ mapM (lowerSafeForeignCalls areaMap) gs
+ mapM_ (dump Opt_D_dump_cmmz_lower "Post lowerSafeForeignCalls") gs
+
+ -- NO MORE GRAPH TRANSFORMATION AFTER HERE -- JUST MAKING INFOTABLES
+ gs <- return $ map (setInfoTableStackMap slotEnv areaMap) gs
+ mapM_ (dump Opt_D_dump_cmmz_info "after setInfoTableStackMap") gs
+ gs <- return $ map (bundleCAFs cafEnv) gs
+ mapM_ (dump Opt_D_dump_cmmz_cafs "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 = do
+ -- ToDo: No easy way of say "dump all the cmmz, *and* split
+ -- them into files." Also, -ddump-cmmz doesn't play nicely
+ -- with -ddump-to-file, since the headers get omitted.
+ dumpIfSet_dyn dflags f txt (ppr g)
+ when (not (dopt f dflags)) $
+ dumpIfSet_dyn dflags Opt_D_dump_cmmz txt (ppr g)
+ -- Runs a required transformation/analysis
+ run = runInfiniteFuelIO (hsc_OptFuel hsc_env)
+ -- Runs an optional transformation/analysis (and should
+ -- thus be subject to optimization fuel)
+ runOptimization = runFuelIO (hsc_OptFuel hsc_env)
+
+-- 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, [[CmmTop]])
+ -> [(CAFSet, CmmTop)] -> IO (TopSRT, [[CmmTop]])
+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
+ return (topSRT, concat gs' : tops)