import CmmLint
import PprCmm
-import Dataflow (cmmLivenessComment, cmmLiveness, CmmLive)
+import Dataflow -- (fixedpoint, cmmLivenessComment, cmmLiveness, CmmLive)
import MachOp
import ForeignCall
import CLabel
+import SMRep
+import Constants
import DynFlags
import ErrUtils
-- 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 ContinuationFormat = [Maybe LocalReg] -- TODO: consider params as part of format
+--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
-type CmmParam = [(CmmReg,MachHint)]
-
+--------------------------------------------------------------------------------
-- For now just select the continuation orders in the order they are in the set with no gaps
-selectContinuationFormat :: UniqFM {-BlockId-} CmmParam -> UniqFM {-BlockId-} CmmLive -> UniqFM {-BlockId-} ContinuationFormat
-selectContinuationFormat param live = mapUFM (map Just . uniqSetToList) live
-
+-- 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)
+-}
+
+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) =
- case last $ init stmts of
+ -- NOTE: assumes that return/jump can *only* appear at end of block
+ case last stmts of
CmmReturn arguments ->
- BasicBlock ident $ (init $ init stmts) ++
- [CmmJump (CmmReg spReg) arguments]
- -- TODO: tail calls
- -- TODO: return direct at the end of a block
+ 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-} ContinuationFormat -> CmmBasicBlock -> CmmBasicBlock
+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 ++ stmts)
+ ContinuationBlock _ -> BasicBlock ident (unpack_continuation curr_format ++ stmts)
where
info = lookupWithDefaultUFM block_infos (panic $ "info: unknown block " ++ (showSDoc $ ppr $ getUnique ident)) ident
- format = lookupWithDefaultUFM formats (panic $ "format: unknown block " ++ (showSDoc $ ppr $ getUnique ident)) ident
- unpack_continuation = CmmAssign spReg (CmmRegOff spReg frame_size) :
- [CmmAssign (CmmLocal reg) (CmmLoad (CmmRegOff spReg (i*stack_slot_size)) (localRegRep reg))
- | (i, Just reg) <- zip [1..] format]
- frame_size = stack_header_size + stack_slot_size * (length format)
- stack_header_size = stack_slot_size -- TODO: check if this could be different than stack_slot_size
- stack_slot_size = 4 -- TODO: find actual variables to be used instead of this
-
-constructContinuation :: UniqFM {-BlockId-} CPSBlockInfo -> UniqFM {-BlockId-} ContinuationFormat -> CmmBasicBlock -> CmmBasicBlock
+ 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 _ ->
BasicBlock ident $
init (init stmts) ++
- pack_continuation ++
+ pack_continuation curr_format cont_format ++
[CmmJump target arguments]
CmmCall target results arguments _ -> panic "unimplemented CmmCall"
- _ -> BasicBlock ident $ (init stmts) ++ build_block_branch
+ -- 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
- format = lookupWithDefaultUFM formats (panic $ "format: 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)"
+ _ -> panic $ "basic block without a branch at the end (unimplemented) " ++ (showSDoc $ ppr $ stmts)
next_block_as_proc_expr = CmmLit $ CmmLabel $ mkReturnPtLabel $ getUnique next_block
- pack_continuation = CmmAssign spReg (CmmRegOff spReg (-frame_size)) :
- CmmStore (CmmReg spReg) next_block_as_proc_expr :
- [CmmStore (CmmRegOff spReg (i*stack_slot_size)) (CmmReg $ CmmLocal reg)
- | (i, Just reg) <- zip [1..] format]
- frame_size = stack_header_size + stack_slot_size * (length format)
- stack_header_size = stack_slot_size -- TODO: check if this could be different than stack_slot_size (e.g. fixedHdrSize depends on PAR and GRAN)
- stack_slot_size = 4 -- TODO: find actual variables to be used instead of this (e.g. cgRepSizeW)
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
- let live = cmmLiveness (map snd broken_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 = selectContinuationFormat (undefined {-TODO-}) live
+
+ 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 blocks_with_live''']
+ --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
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
projects / ghc-hetmet.git / commitdiff