X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Fcmm%2FCmmCPS.hs;h=f26e55f835224893c81c4fc359e0eb7a1dbf464b;hb=f96e9aa0444de0e673b3c4055c6e43299639bc5b;hp=42dfdced36198a2efbf42f2e8b479695190e4e44;hpb=affbe8dae5d7eb350686b42ddbd4f3561b7bd0ec;p=ghc-hetmet.git diff --git a/compiler/cmm/CmmCPS.hs b/compiler/cmm/CmmCPS.hs index 42dfdce..f26e55f 100644 --- a/compiler/cmm/CmmCPS.hs +++ b/compiler/cmm/CmmCPS.hs @@ -10,12 +10,15 @@ import Cmm import CmmLint import PprCmm -import Dataflow import CmmLive import CmmBrokenBlock import CmmProcPoint import CmmCallConv +import CmmInfo +import CmmUtils +import Bitmap +import ClosureInfo import MachOp import ForeignCall import CLabel @@ -39,8 +42,8 @@ import Data.List -- |Top level driver for the CPS pass ----------------------------------------------------------------------------- cmmCPS :: DynFlags -- ^ Dynamic flags: -dcmm-lint -ddump-cps-cmm - -> [Cmm] -- ^ Input C-- with Proceedures - -> IO [Cmm] -- ^ Output CPS transformed C-- + -> [GenCmm CmmStatic CmmInfo CmmStmt] -- ^ Input C-- with Proceedures + -> IO [GenCmm CmmStatic [CmmStatic] CmmStmt] -- ^ Output CPS transformed C-- cmmCPS dflags abstractC = do when (dopt Opt_DoCmmLinting dflags) $ do showPass dflags "CmmLint" @@ -72,20 +75,21 @@ cmmCPS dflags abstractC = do ----------------------------------------------------------------------------- cpsProc :: UniqSupply - -> CmmTop -- ^Input proceedure - -> [CmmTop] -- ^Output proceedure and continuations -cpsProc uniqSupply x@(CmmData _ _) = [x] -cpsProc uniqSupply x@(CmmProc info_table ident params blocks) = cps_procs + -> GenCmmTop CmmStatic CmmInfo CmmStmt -- ^Input proceedure + -> [GenCmmTop CmmStatic [CmmStatic] CmmStmt] -- ^Output proceedure and continuations +cpsProc uniqSupply (CmmData sec dat) = [CmmData sec dat] +cpsProc uniqSupply (CmmProc info ident params blocks) = info_procs where - uniqes :: [[Unique]] - uniqes = map uniqsFromSupply $ listSplitUniqSupply uniqSupply + uniques :: [[Unique]] + uniques = map uniqsFromSupply $ listSplitUniqSupply uniqSupply + info_uniques:block_uniques = uniques -- Break the block at each function call. -- The part after the function call will have to become a continuation. broken_blocks :: [BrokenBlock] broken_blocks = - concat $ zipWith3 breakBlock uniqes blocks - (FunctionEntry ident params:repeat ControlEntry) + concat $ zipWith3 breakBlock block_uniques blocks + (FunctionEntry info ident params:repeat ControlEntry) -- Calculate live variables for each broken block. -- @@ -104,20 +108,40 @@ cpsProc uniqSupply x@(CmmProc info_table ident params blocks) = cps_procs block_env = blocksToBlockEnv broken_blocks -- Group the blocks into continuations based on the set of proc-points. - continuations :: [Continuation] + continuations :: [Continuation (Either C_SRT CmmInfo)] continuations = map (gatherBlocksIntoContinuation proc_points block_env) (uniqSetToList proc_points) -- Select the stack format on entry to each continuation. + -- Return the max stack offset and an association list -- -- This is an association list instead of a UniqFM because -- CLabel's don't have a 'Uniqueable' instance. - formats :: [(CLabel, StackFormat)] + formats :: [(CLabel, (Maybe CLabel, [Maybe LocalReg]))] formats = selectStackFormat live continuations + -- Do a little meta-processing on the stack formats such as + -- getting the individual frame sizes and the maximum frame size + formats' :: (WordOff, [(CLabel, StackFormat)]) + formats' = processFormats formats + + -- TODO FIXME NOW: calculate a real max stack (including function call args) + -- TODO: from the maximum frame size get the maximum stack size. + -- The difference is due to the size taken by function calls. + + -- Update the info table data on the continuations with + -- the selected stack formats. + continuations' :: [Continuation CmmInfo] + continuations' = map (applyStackFormat (snd formats')) continuations + -- Do the actual CPS transform. cps_procs :: [CmmTop] - cps_procs = map (continuationToProc formats) continuations + cps_procs = map (continuationToProc formats') continuations' + + -- Convert the info tables from CmmInfo to [CmmStatic] + -- We might want to put this in another pass eventually + info_procs :: [RawCmmTop] + info_procs = concat (zipWith mkInfoTable info_uniques cps_procs) -------------------------------------------------------------------------------- @@ -136,14 +160,14 @@ cpsProc uniqSupply x@(CmmProc info_table ident params blocks) = cps_procs -- and heap memory (not sure if that's usefull at all though, but it may -- be worth exploring the design space). -continuationLabel (Continuation _ _ l _ _) = l -data Continuation = +continuationLabel (Continuation _ l _ _) = l +data Continuation info = Continuation - Bool -- True => Function entry, False => Continuation/return point - [CmmStatic] -- Info table, may be empty + info --(Either C_SRT CmmInfo) -- Left <=> Continuation created by the CPS + -- Right <=> Function or Proc point CLabel -- Used to generate both info & entry labels CmmFormals -- Argument locals live on entry (C-- procedure params) - [BrokenBlock] -- Code, may be empty. The first block is + [BrokenBlock] -- Code, may be empty. The first block is -- the entry point. The order is otherwise initially -- unimportant, but at some point the code gen will -- fix the order. @@ -152,13 +176,11 @@ data Continuation = -- to a label. To jump to the first block in a Proc, -- use the appropriate CLabel. --- Describes the layout of a stack frame for a continuation data StackFormat = StackFormat { stack_label :: Maybe CLabel, -- The label occupying the top slot stack_frame_size :: WordOff, -- Total frame size in words (not including arguments) - stack_live :: [(LocalReg, WordOff)] -- local reg offsets from stack top - -- TODO: see if the above can be LocalReg + stack_live :: [Maybe LocalReg] -- local reg offsets from stack top } -- A block can be a continuation of a call @@ -191,70 +213,139 @@ collectNonProcPointTargets proc_points blocks current_targets block = gatherBlocksIntoContinuation :: UniqSet BlockId -> BlockEnv BrokenBlock - -> BlockId -> Continuation + -> BlockId -> Continuation (Either C_SRT CmmInfo) gatherBlocksIntoContinuation proc_points blocks start = - Continuation is_entry info_table clabel params body + Continuation info_table clabel params body where children = (collectNonProcPointTargets proc_points blocks (unitUniqSet start) start) `delOneFromUniqSet` start start_block = lookupWithDefaultUFM blocks (panic "TODO") start children_blocks = map (lookupWithDefaultUFM blocks (panic "TODO")) (uniqSetToList children) body = start_block : children_blocks - info_table = [] -- TODO + + -- We can't properly annotate the continuation's stack parameters + -- at this point because this is before stack selection + -- but we want to keep the C_SRT around so we use 'Either'. + info_table = case start_block_entry of + FunctionEntry info _ _ -> Right info + ContinuationEntry _ srt -> Left srt + ControlEntry -> Right CmmNonInfo + start_block_entry = brokenBlockEntry start_block - is_entry = case start_block_entry of - FunctionEntry _ _ -> True - _ -> False clabel = case start_block_entry of - FunctionEntry label _ -> label + FunctionEntry _ label _ -> label _ -> mkReturnPtLabel $ getUnique start params = case start_block_entry of - FunctionEntry _ args -> args + FunctionEntry _ _ args -> args ContinuationEntry args _ -> args ControlEntry -> [] -- TODO: it's a proc-point, we could pass lives in parameter registers -------------------------------------------------------------------------------- -- For now just select the continuation orders in the order they are in the set with no gaps -selectStackFormat :: BlockEnv CmmLive -> [Continuation] -> [(CLabel, StackFormat)] +selectStackFormat :: BlockEnv CmmLive + -> [Continuation (Either C_SRT CmmInfo)] + -> [(CLabel, (Maybe CLabel, [Maybe LocalReg]))] selectStackFormat live continuations = map (\c -> (continuationLabel c, selectStackFormat' c)) continuations where - selectStackFormat' (Continuation True info_table label formals blocks) = - StackFormat (Just label) 0 [] - selectStackFormat' (Continuation False info_table label formals blocks) = + selectStackFormat' (Continuation + (Right (CmmInfo _ _ _ (ContInfo format srt))) + label _ _) = (Just label, format) + selectStackFormat' (Continuation (Right _) _ _ _) = (Nothing, []) + selectStackFormat' (Continuation (Left srt) label _ blocks) = -- TODO: assumes the first block is the entry block let ident = brokenBlockId $ head blocks -- TODO: CLabel isn't a uniquable, but we need a better way than this - in live_to_format label formals $ lookupWithDefaultUFM live unknown_block ident + in (Just label, + map Just $ uniqSetToList $ + lookupWithDefaultUFM live unknown_block ident) - live_to_format :: CLabel -> CmmFormals -> CmmLive -> StackFormat - live_to_format label formals live = - foldl extend_format - (StackFormat (Just label) retAddrSizeW []) - (uniqSetToList (live `minusUniqSet` mkUniqSet formals)) + unknown_block = panic "unknown BlockId in selectStackFormat" - extend_format :: StackFormat -> LocalReg -> StackFormat - extend_format (StackFormat label size offsets) reg = - StackFormat label (slot_size reg + size) ((reg, size) : offsets) +processFormats :: [(CLabel, (Maybe CLabel, [Maybe LocalReg]))] + -> (WordOff, [(CLabel, StackFormat)]) +processFormats formats = (max_size, formats') + where + max_size = foldl max 0 (map (stack_frame_size . snd) formats') + formats' = map make_format formats + make_format (label, format) = + (label, + StackFormat { + stack_label = fst format, + stack_frame_size = stack_size (snd format) + + if isJust (fst format) + then label_size + else 0, + stack_live = snd format }) + + -- TODO: get rid of "+ 1" etc. + label_size = 1 :: WordOff + + stack_size [] = 0 + stack_size (Nothing:formats) = 1 + stack_size formats -- one dead word + stack_size (Just reg:formats) = width + stack_size formats + where + width = machRepByteWidth (localRegRep reg) `quot` wORD_SIZE + -- TODO: it would be better if we had a machRepWordWidth - slot_size :: LocalReg -> Int - slot_size reg = ((machRepByteWidth (localRegRep reg) - 1) `div` wORD_SIZE) + 1 +----------------------------------------------------------------------------- +applyStackFormat :: [(CLabel, StackFormat)] + -> Continuation (Either C_SRT CmmInfo) + -> Continuation CmmInfo + +-- User written continuations +applyStackFormat formats (Continuation + (Right (CmmInfo prof gc tag (ContInfo _ srt))) + label formals blocks) = + Continuation (CmmInfo prof gc tag (ContInfo format srt)) + label formals blocks + where + format = stack_live $ maybe unknown_block id $ lookup label formats + unknown_block = panic "unknown BlockId in applyStackFormat" - unknown_block = panic "unknown BlockId in selectStackFormat" +-- User written non-continuation code +applyStackFormat formats (Continuation (Right info) label formals blocks) = + Continuation info label formals blocks -continuationToProc :: [(CLabel, StackFormat)] -> Continuation -> CmmTop -continuationToProc formats (Continuation is_entry info label formals blocks) = - CmmProc info label formals (map (continuationToProc' label formats) blocks) +-- CPS generated continuations +applyStackFormat formats (Continuation (Left srt) label formals blocks) = + Continuation (CmmInfo prof gc tag (ContInfo (stack_live $ format) srt)) + label formals blocks where - continuationToProc' :: CLabel -> [(CLabel, StackFormat)] -> BrokenBlock - -> CmmBasicBlock - continuationToProc' curr_ident formats (BrokenBlock ident entry stmts _ exit) = + 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 = if stack_frame_size format > mAX_SMALL_BITMAP_SIZE + then rET_BIG + else rET_SMALL + format = maybe unknown_block id $ lookup label formats + unknown_block = panic "unknown BlockId in applyStackFormat" + +----------------------------------------------------------------------------- +continuationToProc :: (WordOff, [(CLabel, StackFormat)]) + -> Continuation CmmInfo + -> CmmTop +continuationToProc (max_stack, formats) + (Continuation info label formals blocks) = + CmmProc info label formals (map continuationToProc' blocks) + where + curr_format = maybe unknown_block id $ lookup label formats + unknown_block = panic "unknown BlockId in continuationToProc" + + continuationToProc' :: BrokenBlock -> CmmBasicBlock + continuationToProc' (BrokenBlock ident entry stmts _ exit) = BasicBlock ident (prefix++stmts++postfix) where - curr_format = maybe unknown_block id $ lookup curr_ident formats - unknown_block = panic "unknown BlockId in continuationToProc" prefix = case entry of ControlEntry -> [] - FunctionEntry _ formals -> -- TODO: gc_stack_check + FunctionEntry (CmmInfo _ (Just gc_block) _ _) _ formals -> + gc_stack_check gc_block max_stack ++ + function_entry formals curr_format + FunctionEntry (CmmInfo _ Nothing _ _) _ formals -> + panic "continuationToProc: TODO generate GC block" ++ + function_entry formals curr_format + FunctionEntry CmmNonInfo _ formals -> + panic "TODO: gc_stack_check gc_block max_stack" ++ function_entry formals curr_format ContinuationEntry formals _ -> function_entry formals curr_format @@ -277,7 +368,7 @@ continuationToProc formats (Continuation is_entry info label formals blocks) = lookup (mkReturnPtLabel $ getUnique next) formats FinalCall next _ results arguments -> panic "unimplemented CmmCall" --------------------------------------------------------------------------------- +----------------------------------------------------------------------------- -- Functions that generate CmmStmt sequences -- for packing/unpacking continuations -- and entering/exiting functions @@ -298,33 +389,45 @@ tail_call spRel target arguments argument_formats = assignArguments (cmmExprRep . fst) arguments -gc_stack_check :: WordOff -> [CmmStmt] -gc_stack_check max_frame_size +gc_stack_check :: BlockId -> WordOff -> [CmmStmt] +gc_stack_check gc_block 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 = panic "gc_check not implemented" -- 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 _) - (StackFormat cont_id cont_frame_size cont_offsets) + (StackFormat cont_id cont_frame_size live_regs) = store_live_values ++ set_stack_header where - -- TODO: only save variables when actually needed (may be handled by latter pass) + -- TODO: only save variables when actually needed + -- (may be handled by latter pass) store_live_values = [stack_put spRel (CmmReg (CmmLocal reg)) offset | (reg, offset) <- cont_offsets] set_stack_header = - if not needs_header - then [] - else [stack_put spRel continuation_function 0] + if needs_header_set + then [stack_put spRel continuation_function 0] + else [] + + -- TODO: factor with function_entry and CmmInfo.hs(?) + cont_offsets = mkOffsets label_size live_regs + + label_size = 1 :: WordOff + + mkOffsets size [] = [] + mkOffsets size (Nothing:regs) = mkOffsets (size+1) regs + mkOffsets size (Just reg:regs) = (reg, size):mkOffsets (size + width) regs + where + width = machRepByteWidth (localRegRep reg) `quot` wORD_SIZE + -- TODO: it would be better if we had a machRepWordWidth spRel = curr_frame_size - cont_frame_size continuation_function = CmmLit $ CmmLabel $ fromJust cont_id - needs_header = + needs_header_set = case (curr_id, cont_id) of (Just x, Just y) -> x /= y _ -> isJust cont_id @@ -334,9 +437,10 @@ pack_continuation (StackFormat curr_id curr_frame_size _) -- have the same stack format (this causes a problem -- only for proc-point). function_entry :: CmmFormals -> StackFormat -> [CmmStmt] -function_entry formals (StackFormat _ _ curr_offsets) +function_entry formals (StackFormat _ _ live_regs) = load_live_values ++ load_args where - -- TODO: only save variables when actually needed (may be handled by latter pass) + -- TODO: only save variables when actually needed + -- (may be handled by latter pass) load_live_values = [stack_get 0 reg offset | (reg, offset) <- curr_offsets] @@ -348,6 +452,18 @@ function_entry formals (StackFormat _ _ curr_offsets) argument_formats = assignArguments (localRegRep) formals + -- TODO: eliminate copy/paste with pack_continuation + curr_offsets = mkOffsets label_size live_regs + + label_size = 1 :: WordOff + + mkOffsets size [] = [] + mkOffsets size (Nothing:regs) = mkOffsets (size+1) regs + mkOffsets size (Just reg:regs) = (reg, size):mkOffsets (size + width) regs + where + width = machRepByteWidth (localRegRep reg) `quot` wORD_SIZE + -- TODO: it would be better if we had a machRepWordWidth + ----------------------------------------------------------------------------- -- Section: Stack and argument register puts and gets ----------------------------------------------------------------------------- @@ -370,7 +486,9 @@ stack_get :: WordOff -> WordOff -> CmmStmt stack_get spRel reg offset = - CmmAssign (CmmLocal reg) (CmmLoad (CmmRegOff spReg (wORD_SIZE*(spRel + offset))) (localRegRep reg)) + CmmAssign (CmmLocal reg) + (CmmLoad (CmmRegOff spReg (wORD_SIZE*(spRel + offset))) + (localRegRep reg)) global_put :: CmmExpr -> GlobalReg -> CmmStmt global_put expr global = CmmAssign (CmmGlobal global) expr global_get :: LocalReg -> GlobalReg -> CmmStmt