X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2Fcmm%2FCmmCPS.hs;h=17c11ce2646c1a17de576c4642beac417508a725;hp=42dfdced36198a2efbf42f2e8b479695190e4e44;hb=d2ce0f52d42edf32bb9f13796e6ba6edba8bd516;hpb=affbe8dae5d7eb350686b42ddbd4f3561b7bd0ec diff --git a/compiler/cmm/CmmCPS.hs b/compiler/cmm/CmmCPS.hs index 42dfdce..17c11ce 100644 --- a/compiler/cmm/CmmCPS.hs +++ b/compiler/cmm/CmmCPS.hs @@ -6,18 +6,19 @@ module CmmCPS ( #include "HsVersions.h" +import BlockId import Cmm import CmmLint import PprCmm -import Dataflow import CmmLive import CmmBrokenBlock import CmmProcPoint import CmmCallConv +import CmmCPSGen +import CmmUtils -import MachOp -import ForeignCall +import ClosureInfo import CLabel import SMRep import Constants @@ -27,13 +28,10 @@ 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 @@ -41,51 +39,99 @@ import Data.List cmmCPS :: DynFlags -- ^ Dynamic flags: -dcmm-lint -ddump-cps-cmm -> [Cmm] -- ^ Input 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" +cmmCPS dflags cmm_with_calls + = do { when (dopt Opt_DoCmmLinting dflags) $ + do showPass dflags "CmmLint" + case firstJust $ 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 } + ----------------------------------------------------------------------------- -- |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 - -> CmmTop -- ^Input proceedure - -> [CmmTop] -- ^Output proceedure and continuations -cpsProc uniqSupply x@(CmmData _ _) = [x] -cpsProc uniqSupply x@(CmmProc info_table ident params blocks) = cps_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 - uniqes :: [[Unique]] - uniqes = map uniqsFromSupply $ listSplitUniqSupply uniqSupply + -- 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 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) + + forced_blocks = stack_check_block : blocks + + 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 uniqes blocks - (FunctionEntry 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. -- @@ -93,94 +139,85 @@ cpsProc uniqSupply x@(CmmProc info_table ident params blocks) = cps_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] - continuations = map (gatherBlocksIntoContinuation proc_points block_env) + continuations :: [Continuation (Either C_SRT CmmInfo)] + 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 -- -- This is an association list instead of a UniqFM because -- CLabel's don't have a 'Uniqueable' instance. - formats :: [(CLabel, StackFormat)] - formats = selectStackFormat live continuations + formats :: [(CLabel, -- key + (CmmFormals, -- arguments + Maybe CLabel, -- label in top slot + [Maybe LocalReg]))] -- slots + 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, 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 (applyContinuationFormat format_list) continuations -- Do the actual CPS transform. cps_procs :: [CmmTop] - cps_procs = map (continuationToProc formats) continuations - --------------------------------------------------------------------------------- - --- 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 = - Continuation - Bool -- True => Function entry, False => Continuation/return point - [CmmStatic] -- Info table, may be empty - 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. - --- 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 - } - --- 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 :: UniqSet BlockId -> BlockEnv BrokenBlock - -> UniqSet BlockId -> BlockId -> UniqSet BlockId -collectNonProcPointTargets proc_points blocks current_targets block = + -> UniqSet BlockId -> [BlockId] -> UniqSet BlockId +collectNonProcPointTargets proc_points blocks current_targets new_blocks = if sizeUniqSet current_targets == sizeUniqSet new_targets then current_targets - else foldl (collectNonProcPointTargets proc_points blocks) new_targets targets + else foldl + (collectNonProcPointTargets proc_points blocks) + new_targets + (map (:[]) targets) where - block' = lookupWithDefaultUFM blocks (panic "TODO") block + 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, -- this subtraction will always remove that case - uniqSetToList $ (mkUniqSet $ brokenBlockTargets block') `minusUniqSet` proc_points + uniqSetToList $ (unionManyUniqSets $ map (mkUniqSet . brokenBlockTargets) blocks') + `minusUniqSet` proc_points -- TODO: remove redundant uniqSetToList new_targets = current_targets `unionUniqSets` (mkUniqSet targets) @@ -190,189 +227,186 @@ collectNonProcPointTargets proc_points blocks current_targets block = -- * Proc points might get some live variables passed as arguments gatherBlocksIntoContinuation :: - UniqSet BlockId -> BlockEnv BrokenBlock - -> BlockId -> Continuation -gatherBlocksIntoContinuation proc_points blocks start = - Continuation is_entry 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 - 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) + 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 - 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 (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 - 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 - ContinuationEntry args _ -> args - ControlEntry -> [] -- TODO: it's a proc-point, we could pass lives in parameter registers + FunctionEntry _ _ args -> args + 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 -> [Continuation] -> [(CLabel, StackFormat)] -selectStackFormat live continuations = - map (\c -> (continuationLabel c, selectStackFormat' c)) continuations +selectContinuationFormat :: BlockEnv CmmLive + -> [Continuation (Either C_SRT CmmInfo)] + -> [(CLabel, (CmmFormals, Maybe CLabel, [Maybe LocalReg]))] +selectContinuationFormat live continuations = + map (\c -> (continuationLabel c, selectContinuationFormat' c)) continuations where - selectStackFormat' (Continuation True info_table label formals blocks) = - StackFormat (Just label) 0 [] - selectStackFormat' (Continuation False info_table label formals 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 live_to_format label formals $ 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)) - - extend_format :: StackFormat -> LocalReg -> StackFormat - extend_format (StackFormat label size offsets) reg = - StackFormat label (slot_size reg + size) ((reg, size) : offsets) - - slot_size :: LocalReg -> Int - slot_size reg = ((machRepByteWidth (localRegRep reg) - 1) `div` wORD_SIZE) + 1 - - unknown_block = panic "unknown BlockId in selectStackFormat" - -continuationToProc :: [(CLabel, StackFormat)] -> Continuation -> CmmTop -continuationToProc formats (Continuation is_entry info label formals blocks) = - CmmProc info label formals (map (continuationToProc' label formats) blocks) + in (formals, + Just label, + map Just $ uniqSetToList $ + lookupWithDefaultBEnv live unknown_block ident) + + unknown_block = panic "unknown BlockId in selectContinuationFormat" + +processFormats :: [(CLabel, (CmmFormals, Maybe CLabel, [Maybe LocalReg]))] + -> Maybe UpdateFrame + -> [Continuation (Either C_SRT CmmInfo)] + -> (WordOff, WordOff, [(CLabel, ContinuationFormat)]) +processFormats formats update_frame continuations = + (max_size + update_frame_size, update_frame_size, formats') where - continuationToProc' :: CLabel -> [(CLabel, StackFormat)] -> BrokenBlock - -> CmmBasicBlock - continuationToProc' curr_ident formats (BrokenBlock ident entry stmts _ exit) = - BasicBlock ident (prefix++stmts++postfix) + max_size = maximum $ + 0 : map (continuationMaxStack formats') continuations + formats' = map make_format formats + make_format (label, (formals, top, stack)) = + (label, + ContinuationFormat { + continuation_formals = formals, + continuation_label = top, + continuation_frame_size = stack_size stack + + if isJust top + then label_size + else 0, + 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 - 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 - function_entry formals curr_format - 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" + width = (widthInBytes $ typeWidth $ cmmExprType expr) `quot` wORD_SIZE + -- TODO: it would be better if we had a machRepWordWidth --------------------------------------------------------------------------------- --- 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 :: WordOff -> [CmmStmt] -gc_stack_check 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) - = 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 not needs_header - then [] - else [stack_put spRel continuation_function 0] - - spRel = curr_frame_size - cont_frame_size - continuation_function = CmmLit $ CmmLabel $ fromJust cont_id - needs_header = - 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 _ _ curr_offsets) - = 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: 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 = (widthInBytes $ typeWidth $ localRegType reg) `quot` wORD_SIZE + -- TODO: it would be better if we had a machRepWordWidth + +continuationMaxStack :: [(CLabel, ContinuationFormat)] + -> Continuation a + -> WordOff +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" + + max_arg_size = maximum $ 0 : map block_max_arg_size blocks + + block_max_arg_size block = + maximum (final_arg_size (brokenBlockExit block) : + map stmt_arg_size (brokenBlockStmts block)) + + final_arg_size (FinalReturn args) = + argumentsSize (cmmExprType . hintlessCmm) args + final_arg_size (FinalJump _ 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 (cmmExprType . hintlessCmm) args + + continuation_frame_size next_format + where + next_format = maybe unknown_format id $ lookup next' formats + next' = mkReturnPtLabel $ getUnique next + + final_arg_size _ = 0 + + stmt_arg_size (CmmJump _ args) = + 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 ----------------------------------------------------------------------------- --- 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)) +applyContinuationFormat :: [(CLabel, ContinuationFormat)] + -> Continuation (Either C_SRT CmmInfo) + -> Continuation CmmInfo + +-- User written continuations +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 = 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 _ (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 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 + -- 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"