-module CmmCPS (cmmCPS) where
+{-# 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 CmmCPS (
+ -- | Converts C-- with full proceedures and parameters
+ -- to a CPS transformed C-- with the stack made manifest.
+ -- Well, sort of.
+ protoCmmCPS
+) where
-#include "HsVersions.h"
-
-import Cmm
-import CmmLint
-import PprCmm
-
-import Dataflow -- (fixedpoint, cmmLivenessComment, cmmLiveness, CmmLive)
-
-import MachOp
-import ForeignCall
import CLabel
-import SMRep
-import Constants
+import Cmm
+import CmmDecl
+import CmmBuildInfoTables
+import CmmCommonBlockElim
+import CmmProcPoint
+import CmmSpillReload
+import CmmStackLayout
+import OptimizationFuel
import DynFlags
import ErrUtils
-import Maybes
+import HscTypes
+import Data.Maybe
+import Control.Monad
+import Data.Map (Map)
+import qualified Data.Map as Map
import Outputable
-import UniqSupply
-import UniqFM
-import UniqSet
-import Unique
-
-import Monad
-import IO
-
---------------------------------------------------------------------------------
--- Monad for the CPSer
--- Contains:
--- * State for the uniqSupply
-
-data CPSState = CPSState { cps_uniqs :: UniqSupply }
-
-data CPS a = CPS { runCPS :: CPSState -> (CPSState, a) }
-
-instance Monad CPS where
- return a = CPS $ \s -> (s, a)
- (CPS m) >>= f = CPS $ \s ->
- let (s', m') = m s
- in runCPS (f m') s'
-
---------------------------------------------------------------------------------
--- Utility functions
-
-getState = CPS $ \s -> (s, s)
-putState s = CPS $ \_ -> (s, ())
-
-newLabelCPS = do
- state <- getState
- let (us1, us2) = splitUniqSupply (cps_uniqs state)
- putState $ state { cps_uniqs = us1 }
- return $ BlockId (uniqFromSupply us2)
-
-mapMCmmTop :: (Monad m) => (CmmTop -> m [CmmTop]) -> Cmm -> m Cmm
-mapMCmmTop f (Cmm xs) = liftM Cmm $ liftM concat $ mapM f xs
-
---------------------------------------------------------------------------------
-
--- The format for the call to a continuation
--- The fst is the arguments that must be passed to the continuation
--- by the continuation's caller.
--- The snd is the live values that must be saved on stack.
--- A Nothing indicates an ignored slot.
--- The head of each list is the stack top or the first parameter.
-
--- The format for live values for a particular continuation
--- All on stack for now.
--- Head element is the top of the stack (or just under the header).
--- Nothing means an empty slot.
--- Future possibilities include callee save registers (i.e. passing slots in register)
--- and heap memory (not sure if that's usefull at all though, but it may
--- be worth exploring the design space).
-
-data BrokenBlock
- = BrokenBlock
- BlockId -- Like a CmmBasicBlock
- BlockEntryInfo -- How this block can be entered
- [CmmStmt] -- Like a CmmBasicBlock (but without
- -- the last statement)
- BlockExitInfo -- How the block can be left
-
-data BlockEntryInfo
- = FunctionEntry -- Beginning of function
-
- | ContinuationEntry -- Return point of a call
- CmmFormals {- return values -}
- -- TODO | ProcPointEntry {- no return values, but some live might end up as params -}
-
- | ControlEntry -- A label in the input
-
-data BlockExitInfo
- = ControlExit [BlockId] -- blocks branched to conditionally
- BlockId -- next block (must be a ControlEntry)
-
- | ReturnExit [BlockId] -- blocks branched to conditionally
- CmmActuals -- return values
-
- | TailCallExit [BlockId] -- blocks branched to conditionally
- CmmExpr -- the function to call
- CmmActuals -- arguments to call
-
- | CallExit [BlockId] -- blocks branched to conditionally
- BlockId -- next block after call (must be a ContinuationEntry)
- CmmCallTarget -- the function to call
- CmmFormals -- results from call (redundant with ContinuationEntry)
- CmmActuals -- arguments to call
- (Maybe [GlobalReg]) -- registers that must be saved (TODO)
- -- TODO: | ProcPointExit (needed?)
-
-data CPSBlockInfo
- = ControlBlock -- Consider whether a proc-point might want arguments on stack
- | ContinuationBlock [(CmmReg,MachHint)] {- params -}
- | EntryBlock
-
---type StackFormat = [Maybe LocalReg] -- TODO: consider params as part of format
-data StackFormat
- = StackFormat
- BlockId {- block that is the start of the continuation. may or may not be the current block -}
- WordOff {- total frame size -}
- [(CmmReg, WordOff)] {- local reg offsets from stack top -}
-
--- A block can be a continuation of a call
--- A block can be a continuation of another block (w/ or w/o joins)
--- A block can be an entry to a function
-
---------------------------------------------------------------------------------
--- For now just select the continuation orders in the order they are in the set with no gaps
--- TODO: select a format that keeps blocks that can jump to each other the same
--- Assumed that jumps, calls
-selectStackFormat :: UniqFM {-BlockId-} CmmFormals -> UniqFM {-BlockId-} CmmLive -> UniqFM {-BlockId-} [(CPSBlockInfo, CmmBasicBlock)] -> UniqFM {-BlockId-} StackFormat
-selectStackFormat = undefined
-{-
-selectStackFormat param live blocks = fixedpoint
-listToUFM $ map live_to_format $ ufmToList live
- where
- live_to_format (unique, live) = (unique, format) where
- format = foldl extend_format
- (StackFormat (BlockId unique) retAddrSizeW [])
- (uniqSetToList live)
- extend_format :: StackFormat -> LocalReg -> StackFormat
- extend_format (StackFormat block size offsets) reg =
- StackFormat block (slot_size reg + size) ((CmmLocal reg, size) : offsets)
+import StaticFlags
+
+-----------------------------------------------------------------------------
+-- |Top level driver for the CPS pass
+-----------------------------------------------------------------------------
+-- 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.
+protoCmmCPS :: 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--
+protoCmmCPS 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
+ 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.
-}
-selectStackFormat2 :: UniqFM {-BlockId-} CmmLive -> [BrokenBlock] -> UniqFM {-BlockId-} StackFormat
-selectStackFormat2 live blocks = fixedpoint dependants update (map brokenBlockId blocks) emptyUFM where
- blocks_ufm = listToUFM $ map (\b -> (brokenBlockId b, b)) blocks
- dependants ident =
- case lookupWithDefaultUFM blocks_ufm (panic "TODO") ident of
- (BrokenBlock _ _ _ (ControlExit exits next)) -> next:exits
- (BrokenBlock _ _ _ (ReturnExit exits _)) -> exits
- (BrokenBlock _ _ _ (TailCallExit exits _ _)) -> exits
- (BrokenBlock _ _ _ (CallExit exits _ _ _ _ _)) -> exits
- update ident cause formats =
- let BrokenBlock _ entry _ _ = lookupWithDefaultUFM blocks_ufm (panic "unknown BlockId in selectStackFormat:live") ident in
- case cause of
- -- Propagate only to blocks entered by branches (not function entry blocks or continuation entry blocks)
- Just cause_name ->
- let cause_format = lookupWithDefaultUFM formats (panic "update signaled for block not in format") cause_name
- in case entry of
- ControlEntry -> Just $ addToUFM formats ident cause_format
- FunctionEntry -> Nothing
- ContinuationEntry _ -> Nothing
- -- Do initial calculates for function blocks
- Nothing ->
- case entry of
- ControlEntry -> Nothing
- FunctionEntry -> Just $ addToUFM formats ident $ StackFormat ident 0 []
- ContinuationEntry _ -> Just $ addToUFM formats ident $ live_to_format ident $ lookupWithDefaultUFM live (panic "TODO") ident
- live_to_format label live =
- foldl extend_format
- (StackFormat label retAddrSizeW [])
- (uniqSetToList live)
- extend_format :: StackFormat -> LocalReg -> StackFormat
- extend_format (StackFormat block size offsets) reg =
- StackFormat block (slot_size reg + size) ((CmmLocal reg, size) : offsets)
-
-slot_size reg = ((machRepByteWidth (localRegRep reg) - 1) `div` wORD_SIZE) + 1
-
-transformReturn :: UniqFM {-BlockId-} CPSBlockInfo -> UniqFM {-BlockId-} StackFormat -> CmmBasicBlock -> CmmBasicBlock
-transformReturn block_infos formats (BasicBlock ident stmts) =
- -- NOTE: assumes that return/jump can *only* appear at end of block
- case last stmts of
- CmmReturn arguments ->
- BasicBlock ident $
- (init stmts) ++
- exit_function curr_format (CmmLoad (CmmReg spReg) wordRep) arguments
- CmmJump target arguments ->
- BasicBlock ident $
- (init stmts) ++
- exit_function curr_format target arguments
- _ -> BasicBlock ident stmts
- where
- curr_format = lookupWithDefaultUFM formats (panic $ "format: unknown block " ++ (showSDoc $ ppr $ getUnique ident)) ident
-
-destructContinuation :: UniqFM {-BlockId-} CPSBlockInfo -> UniqFM {-BlockId-} StackFormat -> CmmBasicBlock -> CmmBasicBlock
-destructContinuation block_infos formats (BasicBlock ident stmts) =
- case info of
- ControlBlock -> BasicBlock ident stmts
- ContinuationBlock _ -> BasicBlock ident (unpack_continuation curr_format ++ stmts)
- where
- info = lookupWithDefaultUFM block_infos (panic $ "info: unknown block " ++ (showSDoc $ ppr $ getUnique ident)) ident
- curr_format = lookupWithDefaultUFM formats (panic $ "format: unknown block " ++ (showSDoc $ ppr $ getUnique ident)) ident
-
-constructContinuation2 :: UniqFM {-BlockId-} StackFormat -> BrokenBlock -> CmmBasicBlock
-constructContinuation2 formats (BrokenBlock ident entry stmts exit) =
- BasicBlock ident (prefix++stmts++postfix)
- where
- curr_format = lookupWithDefaultUFM formats (panic $ "format: unknown block " ++ (showSDoc $ ppr $ getUnique ident)) ident
- prefix = case entry of
- ControlEntry -> []
- FunctionEntry -> []
- ContinuationEntry formals -> unpack_continuation curr_format
- postfix = case exit of
- ControlExit _ next -> [CmmBranch next]
- ReturnExit _ arguments -> exit_function curr_format (CmmLoad (CmmReg spReg) wordRep) arguments
- TailCallExit _ target arguments -> exit_function curr_format target arguments
- -- TODO: do something about global saves
- CallExit _ next (CmmForeignCall target CmmCallConv) results arguments saves ->
- let cont_format = lookupWithDefaultUFM formats (panic $ "format: unknown block " ++ (showSDoc $ ppr $ getUnique next)) next
- in pack_continuation curr_format cont_format ++
- [CmmJump target arguments]
- CallExit _ next _ results arguments saves -> panic "unimplemented CmmCall"
-
-constructContinuation :: UniqFM {-BlockId-} CPSBlockInfo -> UniqFM {-BlockId-} StackFormat -> CmmBasicBlock -> CmmBasicBlock
-constructContinuation block_infos formats (BasicBlock ident stmts) =
- case last $ init stmts of
- -- TODO: global_saves
- --CmmCall (CmmForeignCall target CmmCallConv) results arguments (Just []) -> --TODO: handle globals
- CmmCall (CmmForeignCall target CmmCallConv) results arguments _ ->
- BasicBlock ident $
- init (init stmts) ++
- pack_continuation curr_format cont_format ++
- [CmmJump target arguments]
- CmmCall target results arguments _ -> panic "unimplemented CmmCall"
- -- TODO: branches for proc-points
- -- _ -> BasicBlock ident $ (init stmts) ++ build_block_branch
- _ -> BasicBlock ident stmts
- where
- info = lookupWithDefaultUFM block_infos (panic $ "info: unknown block " ++ (showSDoc $ ppr $ getUnique next_block)) next_block
- cont_format = lookupWithDefaultUFM formats (panic $ "format: unknown block " ++ (showSDoc $ ppr $ getUnique next_block)) next_block
- curr_format = lookupWithDefaultUFM formats (panic $ "format: unknown block " ++ (showSDoc $ ppr $ getUnique next_block)) ident
- next_block = case last stmts of
- CmmBranch next -> next
- -- TODO: blocks with jump at end
- -- TODO: blocks with return at end
- _ -> panic $ "basic block without a branch at the end (unimplemented) " ++ (showSDoc $ ppr $ stmts)
- next_block_as_proc_expr = CmmLit $ CmmLabel $ mkReturnPtLabel $ getUnique next_block
- block_needs_call = True -- TODO: use a table (i.e. proc-point)
- build_block_branch =
- if block_needs_call
- then [CmmJump next_block_as_proc_expr [] {- TODO: pass live -}] {- NOTE: a block can never be both a continuation and a controll block -}
- else [CmmBranch next_block]
-
---------------------------------------------------------------------------------
--- Functions that generate CmmStmt sequences
--- for packing/unpacking continuations
--- and entering/exiting functions
-
-exit_function :: StackFormat -> CmmExpr -> CmmActuals -> [CmmStmt]
-exit_function (StackFormat curr_id curr_frame_size curr_offsets) target arguments
- = adjust_spReg ++ jump where
- adjust_spReg = [
- CmmAssign spReg
- (CmmRegOff spReg (curr_frame_size*wORD_SIZE))]
- jump = [CmmJump target arguments]
-
-enter_function :: WordOff -> [CmmStmt]
-enter_function max_frame_size
- = check_stack_limit where
- check_stack_limit = [
- CmmCondBranch
- (CmmMachOp (MO_U_Lt $ cmmRegRep spReg)
- [CmmRegOff spReg max_frame_size, CmmReg spLimReg])
- gc_block]
- gc_block = undefined -- TODO: get stack and heap checks to go to same
-
--- TODO: fix branches to proc point (we have to insert a new block to marshel the continuation)
-pack_continuation :: StackFormat -> StackFormat -> [CmmStmt]
-pack_continuation (StackFormat curr_id curr_frame_size curr_offsets)
- (StackFormat cont_id cont_frame_size cont_offsets)
- = save_live_values ++ set_stack_header ++ adjust_spReg where
- -- TODO: only save variables when actually needed
- save_live_values =
- [CmmStore
- (CmmRegOff
- spReg (wORD_SIZE*(curr_frame_size - cont_frame_size + offset)))
- (CmmReg reg)
- | (reg, offset) <- cont_offsets]
- set_stack_header = -- TODO: only set when needed
- [CmmStore (CmmRegOff spReg (wORD_SIZE*(curr_frame_size - cont_frame_size))) continuation_function]
- continuation_function = CmmLit $ CmmLabel $ mkReturnPtLabel $ getUnique cont_id
- adjust_spReg =
- if curr_frame_size == cont_frame_size
- then []
- else [CmmAssign spReg (CmmRegOff spReg ((curr_frame_size - cont_frame_size)*wORD_SIZE))]
-
--- Lazy adjustment of stack headers assumes all blocks
--- that could branch to eachother (i.e. control blocks)
--- have the same stack format (this causes a problem
--- only for proc-point).
-unpack_continuation :: StackFormat -> [CmmStmt]
-unpack_continuation (StackFormat curr_id curr_frame_size curr_offsets)
- = load_live_values where
- -- TODO: only save variables when actually needed
- load_live_values =
- [CmmAssign
- reg
- (CmmLoad (CmmRegOff spReg (wORD_SIZE*offset)) (cmmRegRep reg))
- | (reg, offset) <- curr_offsets]
-
--- TODO: TBD when to adjust the stack
-
-cpsProc :: CmmTop -> CPS [CmmTop]
-cpsProc x@(CmmData _ _) = return [x]
-cpsProc x@(CmmProc info_table ident params blocks) = do
-
- broken_blocks <- liftM concat $ mapM breakBlock blocks
- broken_blocks2 <- liftM concat (zipWithM breakBlock2 blocks (FunctionEntry:repeat ControlEntry))
- -- broken_blocks :: [BrokenBlock]
-
- let live = cmmLiveness (map snd broken_blocks)
- let live2 :: BlockEntryLiveness
- live2 = cmmLiveness2 broken_blocks2
-
- let blocks_with_live = map (cmmLivenessComment live . snd) broken_blocks
-
- let formats = selectStackFormat (panic "params to selectStackFormat" {-TODO-}) live (undefined)
- let formats2 :: BlockEnv StackFormat -- Stack format on entry
- formats2 = selectStackFormat2 live2 broken_blocks2
-
- let block_infos = listToUFM $ map (\(info, block) -> (blockId block, info)) broken_blocks
- --let blocks_with_live' = map (constructContinuation block_infos formats) blocks_with_live
- --let blocks_with_live'' = map (destructContinuation block_infos formats) blocks_with_live'
- --let blocks_with_live''' = map (transformReturn block_infos formats) blocks_with_live''
-
- return $ [CmmProc info_table ident params $ map (constructContinuation2 formats2) broken_blocks2]
-{-
- return $ [CmmProc info_table ident params $
- map (constructContinuation block_infos formats .
- destructContinuation block_infos formats .
- transformReturn block_infos formats)
- blocks_with_live]
--}
-
---------------------------------------------------------------------------------
--- Takes a basic block and returns a list of basic blocks that
--- each have at most 1 CmmCall in them which must occur at the end.
--- Also returns with each basic block, the variables that will
--- be arguments to the continuation of the block once the call (if any) returns.
-
-cmmBlockifyCalls :: [CmmBasicBlock] -> CPS [(CPSBlockInfo, CmmBasicBlock)]
-cmmBlockifyCalls blocks = liftM concat $ mapM breakBlock blocks
-
--- [(CmmReg,MachHint)] is the results from the previous block that are expected as parameters
---breakBlock :: CmmBasicBlock -> CPS [(Maybe BlockId, CmmBasicBlock)]
-breakBlock :: CmmBasicBlock -> CPS [(CPSBlockInfo, CmmBasicBlock)]
-breakBlock (BasicBlock ident stmts) = breakBlock' ident ControlBlock [] stmts
-
-breakBlock' current_id block_info accum_stmts [] =
- return [(block_info, BasicBlock current_id accum_stmts)]
--- TODO: notice a call just before a branch, jump, call, etc.
-breakBlock' current_id block_info accum_stmts (stmt@(CmmCall _ results _ _):stmts) = do
- new_id <- newLabelCPS
- let new_block = (block_info, BasicBlock current_id (accum_stmts ++ [stmt, CmmBranch new_id]))
- rest <- breakBlock' new_id (ContinuationBlock results) [] stmts
- return $ (new_block:rest)
-breakBlock' current_id arguments accum_stmts (stmt:stmts) =
- breakBlock' current_id arguments (accum_stmts ++ [stmt]) stmts
-
-breakBlock2 (BasicBlock ident stmts) entry = breakBlock2' ident entry [] [] stmts
-
-breakBlock2' current_id block_info exits accum_stmts [] =
- panic "block doesn't end in jump, goto or return"
-breakBlock2' current_id entry exits accum_stmts [CmmJump target arguments] =
- return [BrokenBlock current_id entry accum_stmts (TailCallExit exits target arguments)]
-breakBlock2' current_id entry exits accum_stmts [CmmReturn arguments] =
- return [BrokenBlock current_id entry accum_stmts (ReturnExit exits arguments)]
-breakBlock2' current_id entry exits accum_stmts [CmmBranch target] =
- return [BrokenBlock current_id entry accum_stmts (ControlExit exits target)]
-breakBlock2' _ _ _ _ (CmmJump _ _:_) = panic "jump in middle of block"
-breakBlock2' _ _ _ _ (CmmReturn _:_) = panic "return in middle of block"
-breakBlock2' _ _ _ _ (CmmBranch _:_) = panic "branch in middle of block"
-breakBlock2' _ _ _ _ (CmmSwitch _ _:_) = panic "switch in block not implemented"
-breakBlock2' current_id entry exits accum_stmts (CmmCall target results arguments saves:stmts) = do
- new_id <- newLabelCPS
- rest <- breakBlock2' new_id (ContinuationEntry results) [] [] stmts
- return $ BrokenBlock current_id entry accum_stmts (CallExit exits new_id target results arguments saves) : rest
-breakBlock2' current_id entry exits accum_stmts (s@(CmmCondBranch test target):stmts) =
- breakBlock2' current_id entry (target:exits) (accum_stmts++[s]) stmts
-breakBlock2' current_id entry exits accum_stmts (s:stmts) =
- breakBlock2' current_id entry exits (accum_stmts++[s]) stmts
-
-brokenBlockTargets (BrokenBlock _ _ _ (TailCallExit exits _ _)) = exits
-brokenBlockTargets (BrokenBlock _ _ _ (ReturnExit exits _)) = exits
-brokenBlockTargets (BrokenBlock _ _ _ (ControlExit exits target)) = target:exits
-brokenBlockTargets (BrokenBlock _ _ _ (CallExit exits next _ _ _ _)) = next:exits
-
-brokenBlockId (BrokenBlock ident _ _ _) = ident
-
-cmmBrokenBlockSources ::
- [BrokenBlock] -> UniqFM {-BlockId-} (UniqSet BlockId)
-cmmBrokenBlockSources blocks = foldr aux emptyUFM blocks where
- aux block sourcesUFM =
- foldr add_source_edges sourcesUFM targets where
- add_source_edges t ufm =
- addToUFM_Acc (flip addOneToUniqSet) unitUniqSet ufm t ident
- targets = brokenBlockTargets block
- ident = brokenBlockId block
-
-cmmBrokenBlockNames :: [BrokenBlock] -> UniqFM {-BlockId-} BrokenBlock
-cmmBrokenBlockNames blocks = listToUFM $ map block_name blocks where
- block_name b = (brokenBlockId b, b)
-
-cmmBrokenBlockDependants :: UniqFM {-BlockId-} (UniqSet BlockId) -> BlockId -> [BlockId]
-cmmBrokenBlockDependants sources ident =
- uniqSetToList $ lookupWithDefaultUFM sources emptyUniqSet ident
-
-cmmBrokenBlockLive :: UniqFM {-BlockId-} CmmLive -> BrokenBlock -> CmmLive
-cmmBrokenBlockLive other_live (BrokenBlock _ _ stmts exit) =
- foldr ((.) . (cmmStmtLive other_live)) id stmts live_at_end
- where
- live_at_end =
- case exit of
- ControlExit _ _ -> emptyUniqSet
- ReturnExit _ actuals -> foldr ((.) . cmmExprLive) id (map fst actuals) emptyUniqSet
- TailCallExit _ target actuals ->
- cmmExprLive target $ foldr ((.) . cmmExprLive) id (map fst actuals) $ emptyUniqSet
- CallExit _ _ target _ actuals live ->
- target_liveness $
- foldr ((.) . cmmExprLive) id (map fst actuals) $
- emptyUniqSet
- where
- only_local_regs [] = []
- only_local_regs ((CmmGlobal _,_):args) = only_local_regs args
- only_local_regs ((CmmLocal r,_):args) = r:only_local_regs args
- target_liveness =
- case target of
- (CmmForeignCall target _) -> cmmExprLive target
- (CmmPrim _) -> id
-
-
-cmmBrokenBlockUpdate ::
- UniqFM {-BlockId-} BrokenBlock
- -> BlockId
- -> Maybe BlockId
- -> UniqFM {-BlockId-} CmmLive
- -> Maybe (UniqFM {-BlockId-} CmmLive)
-cmmBrokenBlockUpdate blocks node _ state =
- let old_live = lookupWithDefaultUFM state (panic "unknown block id during liveness analysis") node
- block = lookupWithDefaultUFM blocks (panic "unknown block id during liveness analysis") node
- new_live = cmmBrokenBlockLive state block
- in if (sizeUniqSet old_live) == (sizeUniqSet new_live)
- then Nothing
- else Just $ addToUFM state node new_live
-
-
-cmmLiveness2 :: [BrokenBlock] -> UniqFM {-BlockId-} CmmLive
-cmmLiveness2 blocks =
- fixedpoint (cmmBrokenBlockDependants sources) (cmmBrokenBlockUpdate blocks')
- (map brokenBlockId blocks) (listToUFM [(brokenBlockId b, emptyUniqSet) | b <- blocks]) where
- sources = cmmBrokenBlockSources blocks
- blocks' = cmmBrokenBlockNames blocks
-
---------------------------------------------------------------------------------
-cmmCPS :: DynFlags
- -> [Cmm] -- C-- with Proceedures
- -> IO [Cmm] -- Output: CPS transformed C--
-
-cmmCPS dflags abstractC = do
- when (dopt Opt_DoCmmLinting dflags) $
- do showPass dflags "CmmLint"
- case firstJust $ map cmmLint abstractC of
- Just err -> do printDump err
- ghcExit dflags 1
- Nothing -> return ()
- showPass dflags "CPS"
- -- TODO: check for use of branches to non-existant blocks
- -- TODO: check for use of Sp, SpLim, R1, R2, etc.
- -- continuationC <- return abstractC
- -- TODO: find out if it is valid to create a new unique source like this
- uniqSupply <- mkSplitUniqSupply 'p'
- let (_, continuationC) = runCPS (mapM (mapMCmmTop cpsProc) abstractC) (CPSState uniqSupply)
-
- dumpIfSet_dyn dflags Opt_D_dump_cps_cmm "CPS Cmm" (pprCmms continuationC)
- -- TODO: add option to dump Cmm to file
- return continuationC
+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 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
+
+ -- 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 "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 ()
+ let areaMap = layout procPoints slotEnv entry_off g
+ mbpprTrace "areaMap" (ppr areaMap) $ return ()
+
+ ------------ Manifest 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 g)
+ mapM_ (dump Opt_D_dump_cmmz "after 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 "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 = 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, [[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)