X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2Fcmm%2FCmmCPS.hs;h=7bfdf8437e054485c7b3f64602f3def17f53ed89;hp=25683eebb1505764fbf453d1eb5f1a06f1cdad1f;hb=edc0bafd3fcd01b85a2e8894e5dfe149eb0e0857;hpb=f96fcdc91b424aafca4d06572864fd20c475eaa0 diff --git a/compiler/cmm/CmmCPS.hs b/compiler/cmm/CmmCPS.hs index 25683ee..7bfdf84 100644 --- a/compiler/cmm/CmmCPS.hs +++ b/compiler/cmm/CmmCPS.hs @@ -6,6 +6,7 @@ module CmmCPS ( #include "HsVersions.h" +import BlockId import Cmm import CmmLint import PprCmm @@ -14,13 +15,10 @@ import CmmLive import CmmBrokenBlock import CmmProcPoint import CmmCallConv -import CmmInfo +import CmmCPSGen import CmmUtils -import Bitmap import ClosureInfo -import MachOp -import ForeignCall import CLabel import SMRep import Constants @@ -30,104 +28,110 @@ import ErrUtils import Maybes import Outputable import UniqSupply -import UniqFM import UniqSet import Unique -import Monad -import IO -import Data.List +import Control.Monad ----------------------------------------------------------------------------- -- |Top level driver for the CPS pass ----------------------------------------------------------------------------- cmmCPS :: DynFlags -- ^ Dynamic flags: -dcmm-lint -ddump-cps-cmm - -> [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" - case firstJust $ map cmmLint abstractC of - Just err -> do printDump err - ghcExit dflags 1 - Nothing -> return () - showPass dflags "CPS" + -> [Cmm] -- ^ Input C-- with Proceedures + -> IO [Cmm] -- ^ Output CPS transformed C-- +cmmCPS dflags cmm_with_calls + = do { when (dopt Opt_DoCmmLinting dflags) $ + do showPass dflags "CmmLint" + case firstJusts $ map cmmLint cmm_with_calls of + Just err -> do printDump err + ghcExit dflags 1 + Nothing -> return () + ; showPass dflags "CPS" -- TODO: more lint checking -- check for use of branches to non-existant blocks -- check for use of Sp, SpLim, R1, R2, etc. - uniqSupply <- mkSplitUniqSupply 'p' - let supplies = listSplitUniqSupply uniqSupply - let doCpsProc s (Cmm c) = - Cmm $ concat $ zipWith cpsProc (listSplitUniqSupply s) c - let continuationC = zipWith doCpsProc supplies abstractC + ; uniqSupply <- mkSplitUniqSupply 'p' + ; let supplies = listSplitUniqSupply uniqSupply + ; let cpsd_cmm = zipWith doCpsProc supplies cmm_with_calls - dumpIfSet_dyn dflags Opt_D_dump_cps_cmm "CPS Cmm" (pprCmms continuationC) + ; dumpIfSet_dyn dflags Opt_D_dump_cps_cmm "CPS Cmm" (pprCmms cpsd_cmm) -- TODO: add option to dump Cmm to file - return continuationC + ; return cpsd_cmm } -stg_gc_gen = mkRtsApFastLabel SLIT("gen_cg_TODO") --panic "Need the label for gc" -make_gc_block block_id fun_label formals safety = BasicBlock block_id stmts - where - stmts = [CmmCall stg_gc_gen_target [] [] safety, - CmmJump fun_expr actuals] - stg_gc_gen_target = - CmmForeignCall (CmmLit (CmmLabel stg_gc_gen)) CmmCallConv - actuals = map (\x -> (CmmReg (CmmLocal x), NoHint)) formals - fun_expr = CmmLit (CmmLabel fun_label) - -force_gc_block old_info block_id fun_label formals = - case old_info of - CmmNonInfo (Just _) -> (old_info, []) - CmmInfo _ (Just _) _ _ -> (old_info, []) - CmmNonInfo Nothing - -> (CmmNonInfo (Just block_id), - [make_gc_block block_id fun_label formals (CmmSafe NoC_SRT)]) - CmmInfo prof Nothing type_tag type_info - -> (CmmInfo prof (Just block_id) type_tag type_info, - [make_gc_block block_id fun_label formals (CmmSafe srt)]) - where - srt = case type_info of - ConstrInfo _ _ _ -> NoC_SRT - FunInfo _ srt' _ _ _ _ -> srt' - ThunkInfo _ srt' -> srt' - ThunkSelectorInfo _ srt' -> srt' - ContInfo _ srt' -> srt' ----------------------------------------------------------------------------- -- |CPS a single CmmTop (proceedure) -- Only 'CmmProc' are transformed 'CmmData' will be left alone. ----------------------------------------------------------------------------- +doCpsProc :: UniqSupply -> Cmm -> Cmm +doCpsProc s (Cmm c) + = Cmm $ concat $ zipWith cpsProc (listSplitUniqSupply s) c + cpsProc :: UniqSupply - -> 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 + -> CmmTop -- ^Input procedure + -> [CmmTop] -- ^Output procedures; + -- a single input procedure is converted to + -- multiple output procedures + +-- Data blocks don't need to be CPS transformed +cpsProc _ proc@(CmmData _ _) = [proc] + +-- Empty functions just don't work with the CPS algorithm, but +-- they don't need the transformation anyway so just output them directly +cpsProc _ proc@(CmmProc _ _ _ (ListGraph [])) + = pprTrace "cpsProc: unexpected empty proc" (ppr proc) [proc] + +-- CPS transform for those procs that actually need it +-- The plan is this: +-- +-- * Introduce a stack-check block as the first block +-- * The first blocks gets a FunctionEntry; the rest are ControlEntry +-- * Now break each block into a bunch of blocks (at call sites); +-- all but the first will be ContinuationEntry +-- +cpsProc uniqSupply (CmmProc info ident params (ListGraph blocks)) = cps_procs where + -- We need to be generating uniques for several things. + -- We could make this function monadic to handle that + -- but since there is no other reason to make it monadic, + -- we instead will just split them all up right here. + (uniqSupply1, uniqSupply2) = splitUniqSupply uniqSupply uniques :: [[Unique]] - uniques = map uniqsFromSupply $ listSplitUniqSupply uniqSupply - (gc_unique:info_uniques):block_uniques = uniques + uniques = map uniqsFromSupply $ listSplitUniqSupply uniqSupply1 + (stack_check_block_unique:stack_use_unique:adaptor_uniques) : + block_uniques = uniques + proc_uniques = map (map (map uniqsFromSupply . listSplitUniqSupply) . listSplitUniqSupply) $ listSplitUniqSupply uniqSupply2 + + stack_use = CmmLocal (LocalReg stack_use_unique (cmmRegType spReg)) + stack_check_block_id = BlockId stack_check_block_unique + stack_check_block = make_stack_check stack_check_block_id info stack_use (blockId $ head blocks) - -- Ensure that - forced_gc :: (CmmInfo, [CmmBasicBlock]) - forced_gc = force_gc_block info (BlockId gc_unique) ident params + forced_blocks = stack_check_block : blocks - forced_info = fst forced_gc - forced_blocks = blocks ++ snd forced_gc - forced_gc_id = case forced_info of - CmmNonInfo (Just x) -> x - CmmInfo _ (Just x) _ _ -> x + CmmInfo maybe_gc_block_id update_frame _ = info -- Break the block at each function call. -- The part after the function call will have to become a continuation. - broken_blocks :: [BrokenBlock] + broken_blocks :: ([(BlockId, ContFormat)], [BrokenBlock]) broken_blocks = - concat $ zipWith3 breakBlock block_uniques forced_blocks - (FunctionEntry forced_info ident params:repeat ControlEntry) + (\x -> (concatMap fst x, concatMap snd x)) $ + zipWith3 (breakBlock (maybeToList maybe_gc_block_id)) + block_uniques + forced_blocks + (FunctionEntry info ident params : + repeat ControlEntry) + + f' = selectContinuations (fst broken_blocks) + broken_blocks' = map (makeContinuationEntries f') $ + concat $ + zipWith (adaptBlockToFormat f') + adaptor_uniques + (snd broken_blocks) -- Calculate live variables for each broken block. -- @@ -135,22 +139,20 @@ cpsProc uniqSupply (CmmProc info ident params blocks) = info_procs -- so we could take the tail, but for now we wont -- to help future proof the code. live :: BlockEntryLiveness - live = cmmLiveness $ map cmmBlockFromBrokenBlock broken_blocks + live = cmmLiveness $ map cmmBlockFromBrokenBlock broken_blocks' -- Calculate which blocks must be made into full fledged procedures. proc_points :: UniqSet BlockId - proc_points = calculateProcPoints broken_blocks + proc_points = calculateProcPoints broken_blocks' -- Construct a map so we can lookup a broken block by its 'BlockId'. block_env :: BlockEnv BrokenBlock - block_env = blocksToBlockEnv broken_blocks + block_env = blocksToBlockEnv broken_blocks' -- Group the blocks into continuations based on the set of proc-points. continuations :: [Continuation (Either C_SRT CmmInfo)] - continuations = zipWith - (gatherBlocksIntoContinuation proc_points block_env) - (uniqSetToList proc_points) - (Just forced_gc_id : repeat Nothing) + continuations = map (gatherBlocksIntoContinuation live 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 @@ -158,73 +160,44 @@ cpsProc uniqSupply (CmmProc info ident params blocks) = info_procs -- This is an association list instead of a UniqFM because -- CLabel's don't have a 'Uniqueable' instance. formats :: [(CLabel, -- key - (Maybe CLabel, -- label in top slot + (CmmFormals, -- arguments + Maybe CLabel, -- label in top slot [Maybe LocalReg]))] -- slots - formats = selectStackFormat live continuations + formats = selectContinuationFormat 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 continuations + formats' :: (WordOff, WordOff, [(CLabel, ContinuationFormat)]) + formats'@(_, _, format_list) = processFormats formats update_frame continuations -- Update the info table data on the continuations with -- the selected stack formats. continuations' :: [Continuation CmmInfo] - continuations' = map (applyStackFormat (snd formats')) continuations + continuations' = map (applyContinuationFormat format_list) continuations -- Do the actual CPS transform. cps_procs :: [CmmTop] - 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) - --------------------------------------------------------------------------------- - --- 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). - -continuationLabel (Continuation _ l _ _) = l -data Continuation info = - Continuation - info -- 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 - -- the entry point. The order is otherwise initially - -- unimportant, but at some point the code gen will - -- fix the order. - - -- the BlockId of the first block does not give rise - -- to a label. To jump to the first block in a Proc, - -- use the appropriate CLabel. - -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 :: [Maybe LocalReg] -- 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 + cps_procs = zipWith (continuationToProc formats' stack_use) proc_uniques continuations' +make_stack_check :: BlockId -> CmmInfo -> CmmReg -> BlockId + -> GenBasicBlock CmmStmt +make_stack_check stack_check_block_id info stack_use next_block_id = + BasicBlock stack_check_block_id $ + check_stmts ++ [CmmBranch next_block_id] + where + check_stmts = + case info of + -- If we are given a stack check handler, + -- then great, well check the stack. + CmmInfo (Just gc_block) _ _ + -> [CmmCondBranch + (CmmMachOp (MO_U_Lt (typeWidth (cmmRegType spReg))) + [CmmReg stack_use, CmmReg spLimReg]) + gc_block] + -- If we aren't given a stack check handler, + -- then humph! we just won't check the stack for them. + CmmInfo Nothing _ _ + -> [] ----------------------------------------------------------------------------- collectNonProcPointTargets :: @@ -238,7 +211,7 @@ collectNonProcPointTargets proc_points blocks current_targets new_blocks = new_targets (map (:[]) targets) where - blocks' = map (lookupWithDefaultUFM blocks (panic "TODO")) new_blocks + blocks' = map (lookupWithDefaultBEnv blocks (panic "TODO")) new_blocks targets = -- Note the subtlety that since the extra branch after a call -- will always be to a block that is a proc-point, @@ -254,25 +227,30 @@ collectNonProcPointTargets proc_points blocks current_targets new_blocks = -- * Proc points might get some live variables passed as arguments gatherBlocksIntoContinuation :: - UniqSet BlockId -> BlockEnv BrokenBlock - -> BlockId -> Maybe BlockId -> Continuation (Either C_SRT CmmInfo) -gatherBlocksIntoContinuation proc_points blocks start gc = - Continuation info_table clabel params body + BlockEntryLiveness -> UniqSet BlockId -> BlockEnv BrokenBlock + -> BlockId -> Continuation (Either C_SRT CmmInfo) +gatherBlocksIntoContinuation live proc_points blocks start = + Continuation info_table clabel params is_gc_cont body where - start_and_gc = start : maybeToList gc - children = (collectNonProcPointTargets proc_points blocks (mkUniqSet start_and_gc) start_and_gc) `minusUniqSet` (mkUniqSet start_and_gc) - start_block = lookupWithDefaultUFM blocks (panic "TODO") start - gc_block = map (lookupWithDefaultUFM blocks (panic "TODO)")) (maybeToList gc) - children_blocks = map (lookupWithDefaultUFM blocks (panic "TODO")) (uniqSetToList children) - body = start_block : gc_block ++ children_blocks + children = (collectNonProcPointTargets proc_points blocks (unitUniqSet start) [start]) `minusUniqSet` (unitUniqSet start) + start_block = lookupWithDefaultBEnv blocks unknown_block start + children_blocks = map (lookupWithDefaultBEnv blocks unknown_block) (uniqSetToList children) + unknown_block :: a -- Used at more than one type + unknown_block = panic "unknown block in gatherBlocksIntoContinuation" + body = start_block : children_blocks -- 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 Nothing) + ContinuationEntry _ srt _ -> Left srt + ControlEntry -> Right (CmmInfo Nothing Nothing CmmNonInfoTable) + + is_gc_cont = case start_block_entry of + FunctionEntry _ _ _ -> False + ContinuationEntry _ _ gc_cont -> gc_cont + ControlEntry -> False start_block_entry = brokenBlockEntry start_block clabel = case start_block_entry of @@ -280,48 +258,72 @@ gatherBlocksIntoContinuation proc_points blocks start gc = _ -> mkReturnPtLabel $ getUnique start params = case start_block_entry of FunctionEntry _ _ args -> args - ContinuationEntry args _ -> args - ControlEntry -> [] -- TODO: it's a proc-point, we could pass lives in parameter registers + ContinuationEntry args _ _ -> args + ControlEntry -> + uniqSetToList $ + lookupWithDefaultBEnv live unknown_block start + -- it's a proc-point, 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 +selectContinuationFormat :: BlockEnv CmmLive -> [Continuation (Either C_SRT CmmInfo)] - -> [(CLabel, (Maybe CLabel, [Maybe LocalReg]))] -selectStackFormat live continuations = - map (\c -> (continuationLabel c, selectStackFormat' c)) continuations + -> [(CLabel, (CmmFormals, Maybe CLabel, [Maybe LocalReg]))] +selectContinuationFormat live continuations = + map (\c -> (continuationLabel c, selectContinuationFormat' c)) continuations where - selectStackFormat' (Continuation - (Right (CmmInfo _ _ _ (ContInfo format srt))) - label _ _) = (Just label, format) - selectStackFormat' (Continuation (Right _) _ _ _) = (Nothing, []) - selectStackFormat' (Continuation (Left srt) label _ blocks) = + -- User written continuations + selectContinuationFormat' (Continuation + (Right (CmmInfo _ _ (CmmInfoTable _ _ _ (ContInfo format _)))) + label formals _ _) = + (formals, Just label, format) + -- Either user written non-continuation code + -- or CPS generated proc-points + selectContinuationFormat' (Continuation (Right _) _ formals _ _) = + (formals, Nothing, []) + -- CPS generated continuations + selectContinuationFormat' (Continuation (Left _) label formals _ 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 (Just label, + in (formals, + Just label, map Just $ uniqSetToList $ - lookupWithDefaultUFM live unknown_block ident) + lookupWithDefaultBEnv live unknown_block ident) - unknown_block = panic "unknown BlockId in selectStackFormat" + unknown_block = panic "unknown BlockId in selectContinuationFormat" -processFormats :: [(CLabel, (Maybe CLabel, [Maybe LocalReg]))] +processFormats :: [(CLabel, (CmmFormals, Maybe CLabel, [Maybe LocalReg]))] + -> Maybe UpdateFrame -> [Continuation (Either C_SRT CmmInfo)] - -> (WordOff, [(CLabel, StackFormat)]) -processFormats formats continuations = (max_size, formats') + -> (WordOff, WordOff, [(CLabel, ContinuationFormat)]) +processFormats formats update_frame continuations = + (max_size + update_frame_size, update_frame_size, formats') where max_size = maximum $ 0 : map (continuationMaxStack formats') continuations formats' = map make_format formats - make_format (label, format) = + make_format (label, (formals, top, stack)) = (label, - StackFormat { - stack_label = fst format, - stack_frame_size = stack_size (snd format) + - if isJust (fst format) + ContinuationFormat { + continuation_formals = formals, + continuation_label = top, + continuation_frame_size = stack_size stack + + if isJust top then label_size else 0, - stack_live = snd format }) + continuation_stack = stack }) + + update_frame_size = case update_frame of + Nothing -> 0 + (Just (UpdateFrame _ args)) + -> label_size + update_size args + + update_size [] = 0 + update_size (expr:exprs) = width + update_size exprs + where + width = (widthInBytes $ typeWidth $ cmmExprType expr) `quot` wORD_SIZE + -- TODO: it would be better if we had a machRepWordWidth -- TODO: get rid of "+ 1" etc. label_size = 1 :: WordOff @@ -330,14 +332,15 @@ processFormats formats continuations = (max_size, formats') 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 + width = (widthInBytes $ typeWidth $ localRegType reg) `quot` wORD_SIZE -- TODO: it would be better if we had a machRepWordWidth -continuationMaxStack :: [(CLabel, StackFormat)] +continuationMaxStack :: [(CLabel, ContinuationFormat)] -> Continuation a -> WordOff -continuationMaxStack formats (Continuation _ label _ blocks) = - max_arg_size + stack_frame_size stack_format +continuationMaxStack _ (Continuation _ _ _ True _) = 0 +continuationMaxStack formats (Continuation _ label _ False blocks) = + max_arg_size + continuation_frame_size stack_format where stack_format = maybe unknown_format id $ lookup label formats unknown_format = panic "Unknown format in continuationMaxStack" @@ -349,14 +352,15 @@ continuationMaxStack formats (Continuation _ label _ blocks) = map stmt_arg_size (brokenBlockStmts block)) final_arg_size (FinalReturn args) = - argumentsSize (cmmExprRep . fst) args + argumentsSize (cmmExprType . hintlessCmm) args final_arg_size (FinalJump _ args) = - argumentsSize (cmmExprRep . fst) args - final_arg_size (FinalCall next _ _ args) = + argumentsSize (cmmExprType . hintlessCmm) args + final_arg_size (FinalCall _ _ _ _ _ _ True) = 0 + final_arg_size (FinalCall next _ _ args _ _ False) = -- We have to account for the stack used when we build a frame -- for the *next* continuation from *this* continuation - argumentsSize (cmmExprRep . fst) args + - stack_frame_size next_format + argumentsSize (cmmExprType . hintlessCmm) args + + continuation_frame_size next_format where next_format = maybe unknown_format id $ lookup next' formats next' = mkReturnPtLabel $ getUnique next @@ -364,36 +368,39 @@ continuationMaxStack formats (Continuation _ label _ blocks) = final_arg_size _ = 0 stmt_arg_size (CmmJump _ args) = - argumentsSize (cmmExprRep . fst) args - stmt_arg_size (CmmCall _ _ _ (CmmSafe _)) = + argumentsSize (cmmExprType . hintlessCmm) args + stmt_arg_size (CmmCall _ _ _ (CmmSafe _) _) = panic "Safe call in processFormats" stmt_arg_size (CmmReturn _) = panic "CmmReturn in processFormats" stmt_arg_size _ = 0 ----------------------------------------------------------------------------- -applyStackFormat :: [(CLabel, StackFormat)] +applyContinuationFormat :: [(CLabel, ContinuationFormat)] -> 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 +applyContinuationFormat formats + (Continuation (Right (CmmInfo gc update_frame + (CmmInfoTable clos prof tag (ContInfo _ srt)))) + label formals is_gc blocks) = + Continuation (CmmInfo gc update_frame (CmmInfoTable clos prof tag (ContInfo format srt))) + label formals is_gc blocks where - format = stack_live $ maybe unknown_block id $ lookup label formats - unknown_block = panic "unknown BlockId in applyStackFormat" + format = continuation_stack $ maybe unknown_block id $ lookup label formats + unknown_block = panic "unknown BlockId in applyContinuationFormat" --- User written non-continuation code -applyStackFormat formats (Continuation (Right info) label formals blocks) = - Continuation info label formals blocks +-- Either user written non-continuation code or CPS generated proc-point +applyContinuationFormat _ (Continuation + (Right info) label formals is_gc blocks) = + Continuation info label formals is_gc 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 +applyContinuationFormat formats (Continuation + (Left srt) label formals is_gc blocks) = + Continuation (CmmInfo gc Nothing (CmmInfoTable undefined 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 @@ -401,181 +408,5 @@ applyStackFormat formats (Continuation (Left srt) label formals blocks) = 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 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 - prefix = case entry of - ControlEntry -> [] - FunctionEntry (CmmInfo _ (Just gc_block) _ _) _ formals -> - gc_stack_check gc_block max_stack ++ - function_entry formals curr_format - FunctionEntry (CmmInfo _ Nothing _ _) _ formals -> - panic "continuationToProc: missing GC block" - FunctionEntry (CmmNonInfo (Just gc_block)) _ formals -> - gc_stack_check gc_block max_stack ++ - function_entry formals curr_format - FunctionEntry (CmmNonInfo Nothing) _ formals -> - panic "continuationToProc: missing non-info GC block" - ContinuationEntry formals _ -> - function_entry formals curr_format - postfix = case exit of - FinalBranch next -> [CmmBranch next] - FinalSwitch expr targets -> [CmmSwitch expr targets] - FinalReturn arguments -> - tail_call (stack_frame_size curr_format) - (CmmLoad (CmmReg spReg) wordRep) - arguments - FinalJump target arguments -> - tail_call (stack_frame_size curr_format) target arguments - FinalCall next (CmmForeignCall target CmmCallConv) - results arguments -> - pack_continuation curr_format cont_format ++ - tail_call (stack_frame_size curr_format - stack_frame_size cont_format) - target arguments - where - cont_format = maybe unknown_block id $ - 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 - -tail_call :: WordOff -> CmmExpr -> CmmActuals -> [CmmStmt] -tail_call spRel target arguments - = store_arguments ++ adjust_spReg ++ jump where - store_arguments = - [stack_put spRel expr offset - | ((expr, _), StackParam offset) <- argument_formats] ++ - [global_put expr global - | ((expr, _), RegisterParam global) <- argument_formats] - adjust_spReg = - if spRel == 0 - then [] - else [CmmAssign spReg (CmmRegOff spReg (spRel*wORD_SIZE))] - jump = [CmmJump target arguments] - - argument_formats = assignArguments (cmmExprRep . fst) arguments - -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*wORD_SIZE), - CmmReg spLimReg]) - gc_block] - --- 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 live_regs) - = store_live_values ++ set_stack_header where - -- 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 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_set = - case (curr_id, cont_id) of - (Just x, Just y) -> x /= y - _ -> isJust cont_id - --- 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). -function_entry :: CmmFormals -> StackFormat -> [CmmStmt] -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) - load_live_values = - [stack_get 0 reg offset - | (reg, offset) <- curr_offsets] - load_args = - [stack_get 0 reg offset - | (reg, StackParam offset) <- argument_formats] ++ - [global_get reg global - | (reg, RegisterParam global) <- argument_formats] - - 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 ------------------------------------------------------------------------------ --- TODO: document - --- |Construct a 'CmmStmt' that will save a value on the stack -stack_put :: WordOff -- ^ Offset from the real 'Sp' that 'offset' - -- is relative to (added to offset) - -> CmmExpr -- ^ What to store onto the stack - -> WordOff -- ^ Where on the stack to store it - -- (positive <=> higher addresses) - -> CmmStmt -stack_put spRel expr offset = - CmmStore (CmmRegOff spReg (wORD_SIZE*(spRel + offset))) expr - --------------------------------- --- |Construct a -stack_get :: WordOff - -> LocalReg - -> WordOff - -> CmmStmt -stack_get spRel reg offset = - 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 -global_get reg global = CmmAssign (CmmLocal reg) (CmmReg (CmmGlobal global)) + unknown_block = panic "unknown BlockId in applyContinuationFormat"