( -- These data types and names are carefully thought out
Graph(..), LGraph(..), FGraph(..)
, Block(..), ZBlock(..), ZHead(..), ZTail(..), ZLast(..)
- , StackInfo(..), emptyStackInfo
, insertBlock
, HavingSuccessors, succs, fold_succs
, LastNode, mkBranchNode, isBranchNode, branchNodeTarget
import PprCmm()
import Outputable hiding (empty)
-import Panic
-import Maybe
+import Data.Maybe
import Prelude hiding (zip, unzip, last)
-------------------------------------------------------------------------
foldRegsUsed _f z LastExit = z
-data ZHead m = ZFirst BlockId StackInfo
+data ZHead m = ZFirst BlockId
| ZHead (ZHead m) m
-- ZHead is a (reversed) sequence of middle nodes labeled by a BlockId
data ZTail m l = ZLast (ZLast l) | ZTail m (ZTail m l)
-- | Blocks and flow graphs; see Note [Kinds of graphs]
--- For each block, we may need two pieces of information about the stack:
--- 1. If the block is a procpoint, how many bytes are used to pass
--- arguments on the stack?
--- 2. If the block succeeds a call, we need to generate an infotable
--- that describes the stack layout... but only up to the update frame!
--- Note that a block can be a proc point without requiring an infotable.
-data StackInfo = StackInfo { argBytes :: Maybe Int
- , returnOff :: Maybe Int }
- deriving ( Eq )
-emptyStackInfo :: StackInfo
-emptyStackInfo = StackInfo Nothing Nothing
-
data Block m l = Block { bid :: BlockId
- , stackInfo :: StackInfo
, tail :: ZTail m l }
data Graph m l = Graph { g_entry :: (ZTail m l), g_blocks :: (BlockEnv (Block m l)) }
data LGraph m l = LGraph { lg_entry :: BlockId
- , lg_argoffset :: Int -- space (bytes) for incoming args
, lg_blocks :: BlockEnv (Block m l)}
-- Invariant: lg_entry is in domain( lg_blocks )
-- layout or dataflow, however, one will want to use 'postorder_dfs'
-- in order to get the blocks in an order that relates to the control
-- flow in the procedure.
-of_block_list :: BlockId -> Int -> [Block m l] -> LGraph m l -- N log N
+of_block_list :: BlockId -> [Block m l] -> LGraph m l -- N log N
to_block_list :: LGraph m l -> [Block m l] -- N log N
-- | Conversion from LGraph to Graph
graphOfLGraph :: LastNode l => LGraph m l -> Graph m l
-graphOfLGraph (LGraph eid _ blocks) = Graph (ZLast $ mkBranchNode eid) blocks
+graphOfLGraph (LGraph eid blocks) = Graph (ZLast $ mkBranchNode eid) blocks
-- | Traversal: 'postorder_dfs' returns a list of blocks reachable
fold_blocks :: (Block m l -> a -> a) -> a -> LGraph m l -> a
-- | Fold from first to last
-fold_fwd_block :: (BlockId -> StackInfo -> a -> a) -> (m -> a -> a) ->
+fold_fwd_block :: (BlockId -> a -> a) -> (m -> a -> a) ->
(ZLast l -> a -> a) -> Block m l -> a -> a
map_one_block :: (BlockId -> BlockId) -> (m -> m') -> (l -> l') -> Block m l -> Block m' l'
----- block manipulations
-blockId (Block id _ _) = id
+blockId (Block id _) = id
-- | Convert block between forms.
-- These functions are tail-recursive, so we can go as deep as we like
-- without fear of stack overflow.
ht_to_block head tail = case head of
- ZFirst id off -> Block id off tail
+ ZFirst id -> Block id tail
ZHead h m -> ht_to_block h (ZTail m tail)
ht_to_last head (ZLast l) = (head, l)
zip (ZBlock h t) = ht_to_block h t
goto_end (ZBlock h t) = ht_to_last h t
-unzip (Block id off t) = ZBlock (ZFirst id off) t
+unzip (Block id t) = ZBlock (ZFirst id) t
head_id :: ZHead m -> BlockId
-head_id (ZFirst id _) = id
+head_id (ZFirst id) = id
head_id (ZHead h _) = head_id h
last (ZBlock _ t) = lastTail t
------------------ simple graph manipulations
focus :: BlockId -> LGraph m l -> FGraph m l -- focus on edge out of node with id
-focus id (LGraph entry _ blocks) =
+focus id (LGraph entry blocks) =
case lookupBlockEnv blocks id of
Just b -> FGraph entry (unzip b) (delFromBlockEnv blocks id)
Nothing -> panic "asked for nonexistent block in flow graph"
entry :: LGraph m l -> FGraph m l -- focus on edge out of entry node
-entry g@(LGraph eid _ _) = focus eid g
+entry g@(LGraph eid _) = focus eid g
-- | pull out a block satisfying the predicate, if any
splitp_blocks :: (Block m l -> Bool) -> BlockEnv (Block m l) ->
-- Better to get [A,B,C,D]
-postorder_dfs g@(LGraph _ _ blockenv) =
+postorder_dfs g@(LGraph _ blockenv) =
let FGraph id eblock _ = entry g in
zip eblock : postorder_dfs_from_except blockenv eblock (unitBlockSet id)
where
-- vnode ::
-- Block m l -> ([Block m l] -> BlockSet -> a) -> [Block m l] -> BlockSet -> a
- vnode block@(Block id _ _) cont acc visited =
+ vnode block@(Block id _) cont acc visited =
if elemBlockSet id visited then
cont acc visited
else
-- 'b1' what its inline successor is going to be, so that if 'b1' ends with
-- 'goto b2', the goto can be omitted.
-fold_layout f z g@(LGraph eid _ _) = fold (postorder_dfs g) z
+fold_layout f z g@(LGraph eid _) = fold (postorder_dfs g) z
where fold blocks z =
case blocks of [] -> z
[b] -> f b Nothing z
b1 : b2 : bs -> fold (b2 : bs) (f b1 (nextlabel b2) z)
- nextlabel (Block id _ _) =
+ nextlabel (Block id _) =
if id == eid then panic "entry as successor"
else Just id
-- | The rest of the traversals are straightforward
-map_blocks f (LGraph eid off blocks) = LGraph eid off (mapBlockEnv f blocks)
+map_blocks f (LGraph eid blocks) = LGraph eid (mapBlockEnv f blocks)
-map_nodes idm middle last (LGraph eid off blocks) =
- LGraph (idm eid) off (mapBlockEnv (map_one_block idm middle last) blocks)
+map_nodes idm middle last (LGraph eid blocks) =
+ LGraph (idm eid) (mapBlockEnv (map_one_block idm middle last) blocks)
-map_one_block idm middle last (Block id off t) = Block (idm id) off (tail t)
+map_one_block idm middle last (Block id t) = Block (idm id) (tail t)
where tail (ZTail m t) = ZTail (middle m) (tail t)
tail (ZLast LastExit) = ZLast LastExit
tail (ZLast (LastOther l)) = ZLast (LastOther (last l))
-mapM_blocks f (LGraph eid off blocks) = blocks' >>= return . LGraph eid off
+mapM_blocks f (LGraph eid blocks) = blocks' >>= return . LGraph eid
where blocks' =
foldBlockEnv' (\b mblocks -> do { blocks <- mblocks
; b <- f b
; return $ insertBlock b blocks })
(return emptyBlockEnv) blocks
-fold_blocks f z (LGraph _ _ blocks) = foldBlockEnv' f z blocks
-fold_fwd_block first middle last (Block id off t) z = tail t (first id off z)
+fold_blocks f z (LGraph _ blocks) = foldBlockEnv' f z blocks
+fold_fwd_block first middle last (Block id t) z = tail t (first id z)
where tail (ZTail m t) z = tail t (middle m z)
tail (ZLast l) z = last l z
-of_block_list e off blocks = LGraph e off $ foldr insertBlock emptyBlockEnv blocks
-to_block_list (LGraph _ _ blocks) = eltsBlockEnv blocks
+of_block_list e blocks = LGraph e $ foldr insertBlock emptyBlockEnv blocks
+to_block_list (LGraph _ blocks) = eltsBlockEnv blocks
-- We want to be able to scrutinize a single-entry, single-exit 'LGraph' for
is_exit :: Block m l -> Bool
is_exit b = case last (unzip b) of { LastExit -> True; _ -> False }
-splice_head head g@(LGraph _ off _) =
+splice_head head g@(LGraph _ _) =
ASSERT (single_exit g) prepare_for_splicing g splice_one_block splice_many_blocks
where eid = head_id head
splice_one_block tail' =
case ht_to_last head tail' of
- (head, LastExit) -> (LGraph eid off emptyBlockEnv, head)
+ (head, LastExit) -> (LGraph eid emptyBlockEnv, head)
_ -> panic "spliced LGraph without exit"
splice_many_blocks entry exit others =
- (LGraph eid off (insertBlock (zipht head entry) others), exit)
+ (LGraph eid (insertBlock (zipht head entry) others), exit)
splice_head' head g =
ASSERT (single_exitg g) prepare_for_splicing' g splice_one_block splice_many_blocks
splice_head_only head g =
let FGraph eid gentry gblocks = entry g
in case gentry of
- ZBlock (ZFirst _ _) tail ->
- LGraph eid 0 (insertBlock (zipht head tail) gblocks)
+ ZBlock (ZFirst _) tail ->
+ LGraph eid (insertBlock (zipht head tail) gblocks)
_ -> panic "entry not at start of block?!"
splice_head_only' head (Graph tail gblocks) =
let eblock = zipht head tail in
- LGraph (blockId eblock) 0 (insertBlock eblock gblocks)
+ LGraph (blockId eblock) (insertBlock eblock gblocks)
-- the offset probably should never be used, but well, it's correct for this LGraph
--- Translation
-translate txm txl (LGraph eid off blocks) =
+translate txm txl (LGraph eid blocks) =
do blocks' <- foldBlockEnv' txblock (return emptyBlockEnv) blocks
- return $ LGraph eid off blocks'
+ return $ LGraph eid blocks'
where
-- txblock ::
-- Block m l -> tm (BlockEnv (Block m' l')) -> tm (BlockEnv (Block m' l'))
- txblock (Block id boff t) expanded =
+ txblock (Block id t) expanded =
do blocks' <- expanded
- txtail (ZFirst id boff) t blocks'
+ txtail (ZFirst id) t blocks'
-- txtail :: ZHead m' -> ZTail m l -> BlockEnv (Block m' l') ->
-- tm (BlockEnv (Block m' l'))
txtail h (ZTail m t) blocks' =
instance (Outputable m, Outputable l, LastNode l) => Outputable (Block m l) where
ppr = pprBlock
-instance Outputable StackInfo where
- ppr = pprStackInfo
-
instance (Outputable l) => Outputable (ZLast l) where
ppr = pprLast
pprLast LastExit = text "<exit>"
pprLast (LastOther l) = ppr l
-pprStackInfo :: StackInfo -> SDoc
-pprStackInfo cs =
- text "<arg bytes:" <+> ppr (argBytes cs) <+>
- text "ret offset:" <+> ppr (returnOff cs) <> text ">"
-
pprBlock :: (Outputable m, Outputable l, LastNode l) => Block m l -> SDoc
-pprBlock (Block id stackInfo tail) =
- ppr id <> parens (ppr stackInfo) <> colon
+pprBlock (Block id tail) =
+ ppr id <> colon
$$ (nest 3 (ppr tail))
pprLgraph :: (Outputable m, Outputable l, LastNode l) => LGraph m l -> SDoc
-pprLgraph g = text "{" <> text "offset" <> parens (ppr $ lg_argoffset g) $$
+pprLgraph g = text "{" <> text "offset" $$
nest 2 (vcat $ map ppr blocks) $$ text "}"
where blocks = postorder_dfs g
projects / ghc-hetmet.git / blobdiff