-{-# OPTIONS -Wall -fno-warn-name-shadowing #-}
+
-- This module is pure representation and should be imported only by
-- clients that need to manipulate representation and know what
module ZipCfgCmmRep
( CmmZ, CmmTopZ, CmmGraph, CmmBlock, CmmAGraph, Middle(..), Last(..), Convention(..)
+ , ValueDirection(..), CmmBackwardFixedPoint, CmmForwardFixedPoint
+ , insertBetween, pprCmmGraphLikeCmm
)
where
-#include "HsVersions.h"
-
import CmmExpr
import Cmm ( GenCmm(..), GenCmmTop(..), CmmStatic, CmmInfo
- , CmmCallTarget(..), CmmActuals, CmmFormalsWithoutKinds, CmmFormals
- , CmmStmt(CmmJump, CmmSwitch) -- imported in order to call ppr
+ , CmmCallTarget(..), CmmActuals, CmmFormals, CmmKinded(..)
+ , CmmStmt(..) -- imported in order to call ppr on Switch and to
+ -- implement pprCmmGraphLikeCmm
+ , CmmSafety(CmmSafe) -- for pprCmmGraphLikeCmm
+ , CmmReturnInfo(CmmMayReturn) -- for pprCmmGraphLikeCmm
)
import PprCmm()
import CLabel
+import CmmZipUtil
import ClosureInfo
import FastString
import ForeignCall
import MachOp
+import StackSlot
+import qualified ZipCfg as Z
import qualified ZipDataflow as DF
import ZipCfg
import MkZipCfg
+import Util
import Maybes
+import Monad
import Outputable
import Prelude hiding (zip, unzip, last)
+import UniqSet
+import UniqSupply
-type CmmGraph = LGraph Middle Last
-type CmmAGraph = AGraph Middle Last
-type CmmBlock = Block Middle Last
-type CmmZ = GenCmm CmmStatic CmmInfo CmmGraph
-type CmmTopZ = GenCmmTop CmmStatic CmmInfo CmmGraph
+----------------------------------------------------------------------
+----- Type synonyms and definitions
+
+type CmmGraph = LGraph Middle Last
+type CmmAGraph = AGraph Middle Last
+type CmmBlock = Block Middle Last
+type CmmZ = GenCmm CmmStatic CmmInfo CmmGraph
+type CmmTopZ = GenCmmTop CmmStatic CmmInfo CmmGraph
+type CmmBackwardFixedPoint a = DF.BackwardFixedPoint Middle Last a ()
+type CmmForwardFixedPoint a = DF.ForwardFixedPoint Middle Last a ()
data Middle
- = MidNop
- | MidComment FastString
+ = MidComment FastString
| MidAssign CmmReg CmmExpr -- Assign to register
- | MidStore CmmExpr CmmExpr -- Assign to memory location. Size is
+ | MidStore CmmExpr CmmExpr -- Assign to memory location. Size is
-- given by cmmExprRep of the rhs.
| MidUnsafeCall -- An "unsafe" foreign call;
- CmmCallTarget -- just a fat machine instructoin
- CmmFormals -- zero or more results
+ CmmCallTarget -- just a fat machine instruction
+ CmmFormals -- zero or more results
CmmActuals -- zero or more arguments
- | CopyIn -- Move parameters or results from conventional locations to registers
- -- Note [CopyIn invariant]
+ | MidAddToContext -- push a frame on the stack;
+ -- I will return to this frame
+ CmmExpr -- The frame's return address; it must be
+ -- preceded by an info table that describes the
+ -- live variables.
+ [CmmExpr] -- The frame's live variables, to go on the
+ -- stack with the first one at the young end
+
+ | CopyIn -- Move incoming parameters or results from conventional
+ -- locations to registers. Note [CopyIn invariant]
Convention
- CmmFormals
+ CmmFormals -- eventually [CmmKind] will be used only for foreign
+ -- calls and will migrate into 'Convention' (helping to
+ -- drain "the swamp"), leaving this as [LocalReg]
C_SRT -- Static things kept alive by this block
- | CopyOut Convention CmmFormals
-data Last
- = LastReturn CmmActuals -- Return from a function,
- -- with these return values.
-
- | LastJump CmmExpr CmmActuals
- -- Tail call to another procedure
-
- | LastBranch BlockId CmmFormalsWithoutKinds
- -- To another block in the same procedure
- -- The parameters are unused at present.
+ | CopyOut Convention CmmActuals
+ -- Move outgoing parameters or results from registers to
+ -- conventional locations. Every 'LastReturn',
+ -- 'LastJump', or 'LastCall' must be dominated by a
+ -- matching 'CopyOut' in the same basic block.
+ -- As above, '[CmmKind]' will migrate into the foreign calling
+ -- convention, leaving the actuals as '[CmmExpr]'.
+ deriving Eq
- | LastCall { -- A call (native or safe foreign)
- cml_target :: CmmCallTarget,
- cml_actual :: CmmActuals, -- Zero or more arguments
- cml_next :: Maybe BlockId } -- BlockId of continuation, if call returns
+data Last
+ = LastBranch BlockId -- Goto another block in the same procedure
| LastCondBranch { -- conditional branch
cml_pred :: CmmExpr,
cml_true, cml_false :: BlockId
}
+ | LastReturn -- Return from a function; values in a previous CopyOut node
+
+ | LastJump CmmExpr -- Tail call to another procedure; args in a CopyOut node
+
+ | LastCall { -- A call (native or safe foreign); args in CopyOut node
+ cml_target :: CmmExpr, -- never a CmmPrim to a CallishMachOp!
+ cml_cont :: Maybe BlockId } -- BlockId of continuation, if call returns
+
| LastSwitch CmmExpr [Maybe BlockId] -- Table branch
-- The scrutinee is zero-based;
-- zero -> first block
-- Undefined outside range, and when there's a Nothing
data Convention
- = Argument CCallConv -- Used for function formal params
- | Result CCallConv -- Used for function results
-
- | Local -- Used for control transfers within a (pre-CPS) procedure
- -- All jump sites known, never pushed on the stack (hence no SRT)
- -- You can choose whatever calling convention
- -- you please (provided you make sure
- -- all the call sites agree)!
+ = ConventionStandard CCallConv ValueDirection
+ | ConventionPrivate
+ -- Used for control transfers within a (pre-CPS) procedure All
+ -- jump sites known, never pushed on the stack (hence no SRT)
+ -- You can choose whatever calling convention you please
+ -- (provided you make sure all the call sites agree)!
+ -- This data type eventually to be extended to record the convention.
+
deriving Eq
--- ^ In a complete LGraph for a procedure, the [[Exit]] node should not
--- appear, but it is useful in a subgraph (e.g., replacement for a node).
+data ValueDirection = Arguments | Results
+ -- Arguments go with procedure definitions, jumps, and arguments to calls
+ -- Results go with returns and with results of calls.
+ deriving Eq
{-
Note [CopyIn invariant]
~~~~~~~~~~~~~~~~~~~~~~~
-In principle, CopyIn ought to be a First node, but in practice, the
+One might wish for CopyIn to be a First node, but in practice, the
possibility raises all sorts of hairy issues with graph splicing,
rewriting, and so on. In the end, NR finds it better to make the
-placement of CopyIn a dynamic invariant. This change will complicate
-the dataflow fact for the proc-point calculation, but it should make
-things easier in many other respects.
+placement of CopyIn a dynamic invariant; it should normally be the first
+Middle node in the basic block in which it occurs.
-}
+----------------------------------------------------------------------
+----- Splicing between blocks
+-- Given a middle node, a block, and a successor BlockId,
+-- we can insert the middle node between the block and the successor.
+-- We return the updated block and a list of new blocks that must be added
+-- to the graph.
+-- The semantics is a bit tricky. We consider cases on the last node:
+-- o For a branch, we can just insert before the branch,
+-- but sometimes the optimizer does better if we actually insert
+-- a fresh basic block, enabling some common blockification.
+-- o For a conditional branch, switch statement, or call, we must insert
+-- a new basic block.
+-- o For a jump, or return, this operation is impossible.
+
+insertBetween :: MonadUnique m => CmmBlock -> [Middle] -> BlockId -> m (CmmBlock, [CmmBlock])
+insertBetween b ms succId = insert $ goto_end $ unzip b
+ where insert (h, LastOther (LastBranch bid)) =
+ if bid == succId then
+ do (bid', bs) <- newBlocks
+ return (zipht h $ ZLast $ LastOther (LastBranch bid'), bs)
+ else panic "tried to insert between non-adjacent blocks"
+ insert (h, LastOther (LastCondBranch c t f)) =
+ do (t', tbs) <- if t == succId then newBlocks else return $ (t, [])
+ (f', fbs) <- if f == succId then newBlocks else return $ (f, [])
+ return (zipht h $ ZLast $ LastOther (LastCondBranch c t' f'), tbs ++ fbs)
+ insert (h, LastOther (LastCall e (Just k))) =
+ if k == succId then
+ do (id', bs) <- newBlocks
+ return (zipht h $ ZLast $ LastOther (LastCall e (Just id')), bs)
+ else panic "tried to insert between non-adjacent blocks"
+ insert (_, LastOther (LastCall _ Nothing)) =
+ panic "cannot insert after non-returning call"
+ insert (h, LastOther (LastSwitch e ks)) =
+ do (ids, bs) <- mapAndUnzipM mbNewBlocks ks
+ return (zipht h $ ZLast $ LastOther (LastSwitch e ids), join bs)
+ insert (_, LastOther LastReturn) = panic "cannot insert after return"
+ insert (_, LastOther (LastJump _)) = panic "cannot insert after jump"
+ insert (_, LastExit) = panic "cannot insert after exit"
+ newBlocks = do id <- liftM BlockId $ getUniqueM
+ return $ (id, [Block id $
+ foldr ZTail (ZLast (LastOther (LastBranch succId))) ms])
+ mbNewBlocks (Just k) = if k == succId then liftM lift newBlocks
+ else return (Just k, [])
+ mbNewBlocks Nothing = return (Nothing, [])
+ lift (id, bs) = (Just id, bs)
+
+
+----------------------------------------------------------------------
+----- Instance declarations for control flow
+
instance HavingSuccessors Last where
succs = cmmSuccs
fold_succs = fold_cmm_succs
instance LastNode Last where
- mkBranchNode id = LastBranch id []
- isBranchNode (LastBranch _ []) = True
+ mkBranchNode id = LastBranch id
+ isBranchNode (LastBranch _) = True
isBranchNode _ = False
- branchNodeTarget (LastBranch id []) = id
+ branchNodeTarget (LastBranch id) = id
branchNodeTarget _ = panic "asked for target of non-branch"
cmmSuccs :: Last -> [BlockId]
-cmmSuccs (LastReturn {}) = []
-cmmSuccs (LastJump {}) = []
-cmmSuccs (LastBranch id _) = [id]
-cmmSuccs (LastCall _ _ (Just id)) = [id]
-cmmSuccs (LastCall _ _ Nothing) = []
-cmmSuccs (LastCondBranch _ t f) = [f, t] -- meets layout constraint
-cmmSuccs (LastSwitch _ edges) = catMaybes edges
+cmmSuccs (LastReturn {}) = []
+cmmSuccs (LastJump {}) = []
+cmmSuccs (LastBranch id) = [id]
+cmmSuccs (LastCall _ (Just id)) = [id]
+cmmSuccs (LastCall _ Nothing) = []
+cmmSuccs (LastCondBranch _ t f) = [f, t] -- meets layout constraint
+cmmSuccs (LastSwitch _ edges) = catMaybes edges
fold_cmm_succs :: (BlockId -> a -> a) -> Last -> a -> a
fold_cmm_succs _f (LastReturn {}) z = z
fold_cmm_succs _f (LastJump {}) z = z
-fold_cmm_succs f (LastBranch id _) z = f id z
-fold_cmm_succs f (LastCall _ _ (Just id)) z = f id z
-fold_cmm_succs _f (LastCall _ _ Nothing) z = z
+fold_cmm_succs f (LastBranch id) z = f id z
+fold_cmm_succs f (LastCall _ (Just id)) z = f id z
+fold_cmm_succs _f (LastCall _ Nothing) z = z
fold_cmm_succs f (LastCondBranch _ te fe) z = f te (f fe z)
fold_cmm_succs f (LastSwitch _ edges) z = foldl (flip f) z $ catMaybes edges
-
-----------------------------------------------------------------
--- prettyprinting (avoids recursive imports)
+----------------------------------------------------------------------
+----- Instance declarations for register use
+
+instance UserOfLocalRegs Middle where
+ foldRegsUsed f z m = middle m
+ where middle (MidComment {}) = z
+ middle (MidAssign _lhs expr) = fold f z expr
+ middle (MidStore addr rval) = fold f (fold f z addr) rval
+ middle (MidUnsafeCall tgt _ress args) = fold f (fold f z tgt) args
+ middle (MidAddToContext ra args) = fold f (fold f z ra) args
+ middle (CopyIn _ _formals _) = z
+ middle (CopyOut _ actuals) = fold f z actuals
+ fold f z m = foldRegsUsed f z m -- avoid monomorphism restriction
+
+instance UserOfLocalRegs Last where
+ foldRegsUsed f z l = last l
+ where last (LastReturn) = z
+ last (LastJump e) = foldRegsUsed f z e
+ last (LastBranch _id) = z
+ last (LastCall tgt _) = foldRegsUsed f z tgt
+ last (LastCondBranch e _ _) = foldRegsUsed f z e
+ last (LastSwitch e _tbl) = foldRegsUsed f z e
+
+instance DefinerOfLocalRegs Middle where
+ foldRegsDefd f z m = middle m
+ where middle (MidComment {}) = z
+ middle (MidAssign _lhs _) = fold f z _lhs
+ middle (MidStore _ _) = z
+ middle (MidUnsafeCall _ _ _) = z
+ middle (MidAddToContext _ _) = z
+ middle (CopyIn _ _formals _) = fold f z _formals
+ middle (CopyOut _ _) = z
+ fold f z m = foldRegsDefd f z m -- avoid monomorphism restriction
+
+instance DefinerOfLocalRegs Last where
+ foldRegsDefd _ z l = last l
+ where last (LastReturn) = z
+ last (LastJump _) = z
+ last (LastBranch _) = z
+ last (LastCall _ _) = z
+ last (LastCondBranch _ _ _) = z
+ last (LastSwitch _ _) = z
+
+----------------------------------------------------------------------
+----- Instance declarations for prettyprinting (avoids recursive imports)
instance Outputable Middle where
ppr s = pprMiddle s
instance DF.DebugNodes Middle Last
-instance Outputable CmmGraph where
- ppr = pprLgraph
-
debugPpr :: Bool
-#ifdef DEBUG
-debugPpr = True
-#else
-debubPpr = False
-#endif
+debugPpr = debugIsOn
pprMiddle :: Middle -> SDoc
-pprMiddle stmt = (case stmt of
-
- MidNop -> semi
+pprMiddle stmt = pp_stmt <+> pp_debug
+ where
+ pp_stmt = case stmt of
CopyIn conv args _ ->
- if null args then ptext SLIT("empty CopyIn")
- else commafy (map pprHinted args) <+> equals <+>
- ptext SLIT("foreign") <+> doubleQuotes(ppr conv) <+> ptext SLIT("...")
+ if null args then ptext (sLit "empty CopyIn")
+ else commafy (map pprKinded args) <+> equals <+>
+ ptext (sLit "foreign") <+> doubleQuotes(ppr conv) <+> ptext (sLit "...")
CopyOut conv args ->
- if null args then empty
- else ptext SLIT("CopyOut") <+> doubleQuotes(ppr conv) <+>
- parens (commafy (map pprHinted args))
+ ptext (sLit "PreCopyOut: next, pass") <+> doubleQuotes(ppr conv) <+>
+ parens (commafy (map pprKinded args))
-- // text
MidComment s -> text "//" <+> ftext s
hcat [ if null results
then empty
else parens (commafy $ map ppr results) <>
- ptext SLIT(" = "),
- ptext SLIT("call"), space,
+ ptext (sLit " = "),
+ ptext (sLit "call"), space,
doubleQuotes(ppr cconv), space,
- target fn, parens ( commafy $ map ppr args ),
+ ppr_target fn, parens ( commafy $ map ppr args ),
semi ]
- where
- target t@(CmmLit _) = ppr t
- target fn' = parens (ppr fn')
MidUnsafeCall (CmmPrim op) results args ->
pprMiddle (MidUnsafeCall (CmmCallee (CmmLit lbl) CCallConv) results args)
where
lbl = CmmLabel (mkForeignLabel (mkFastString (show op)) Nothing False)
- ) <>
- if debugPpr then empty
- else text " //" <+>
- case stmt of
- MidNop {} -> text "MidNop"
- CopyIn {} -> text "CopyIn"
- CopyOut {} -> text "CopyOut"
- MidComment {} -> text "MidComment"
- MidAssign {} -> text "MidAssign"
- MidStore {} -> text "MidStore"
- MidUnsafeCall {} -> text "MidUnsafeCall"
+ MidAddToContext ra args ->
+ hcat [ ptext (sLit "return via ")
+ , ppr_target ra, parens (commafy $ map ppr args), semi ]
-pprHinted :: Outputable a => (a, MachHint) -> SDoc
-pprHinted (a, NoHint) = ppr a
-pprHinted (a, PtrHint) = doubleQuotes (text "address") <+> ppr a
-pprHinted (a, SignedHint) = doubleQuotes (text "signed") <+> ppr a
-pprHinted (a, FloatHint) = doubleQuotes (text "float") <+> ppr a
+ pp_debug =
+ if not debugPpr then empty
+ else text " //" <+>
+ case stmt of
+ CopyIn {} -> text "CopyIn"
+ CopyOut {} -> text "CopyOut"
+ MidComment {} -> text "MidComment"
+ MidAssign {} -> text "MidAssign"
+ MidStore {} -> text "MidStore"
+ MidUnsafeCall {} -> text "MidUnsafeCall"
+ MidAddToContext {} -> text "MidAddToContext"
+
+
+ppr_target :: CmmExpr -> SDoc
+ppr_target t@(CmmLit _) = ppr t
+ppr_target fn' = parens (ppr fn')
+
+
+pprKinded :: Outputable a => CmmKinded a -> SDoc
+pprKinded (CmmKinded a NoHint) = ppr a
+pprKinded (CmmKinded a PtrHint) = doubleQuotes (text "address") <+> ppr a
+pprKinded (CmmKinded a SignedHint) = doubleQuotes (text "signed") <+> ppr a
+pprKinded (CmmKinded a FloatHint) = doubleQuotes (text "float") <+> ppr a
pprLast :: Last -> SDoc
pprLast stmt = (case stmt of
- LastBranch ident args -> genBranchWithArgs ident args
+ LastBranch ident -> ptext (sLit "goto") <+> ppr ident <> semi
LastCondBranch expr t f -> genFullCondBranch expr t f
- LastJump expr params -> ppr $ CmmJump expr params
- LastReturn results -> hcat [ ptext SLIT("return"), space
- , parens ( commafy $ map pprHinted results )
- , semi ]
+ LastJump expr -> hcat [ ptext (sLit "jump"), space, pprFun expr
+ , ptext (sLit "(...)"), semi]
+ LastReturn -> hcat [ ptext (sLit "return"), space
+ , ptext (sLit "(...)"), semi]
LastSwitch arg ids -> ppr $ CmmSwitch arg ids
- LastCall tgt params k -> genCall tgt params k
+ LastCall tgt k -> genBareCall tgt k
) <>
if debugPpr then empty
else text " //" <+>
LastSwitch {} -> text "LastSwitch"
LastCall {} -> text "LastCall"
-genCall :: CmmCallTarget -> CmmActuals -> Maybe BlockId -> SDoc
-genCall (CmmCallee fn cconv) args k =
- hcat [ ptext SLIT("foreign"), space
- , doubleQuotes(ppr cconv), space
- , target fn, parens ( commafy $ map pprHinted args ), space
- , case k of Nothing -> ptext SLIT("never returns")
- Just k -> ptext SLIT("returns to") <+> ppr k
+genBareCall :: CmmExpr -> Maybe BlockId -> SDoc
+genBareCall fn k =
+ hcat [ ptext (sLit "call"), space
+ , pprFun fn, ptext (sLit "(...)"), space
+ , case k of Nothing -> ptext (sLit "never returns")
+ Just k -> ptext (sLit "returns to") <+> ppr k
, semi ]
where
- target t@(CmmLit _) = ppr t
- target fn' = parens (ppr fn')
-genCall (CmmPrim op) args k =
- hcat [ text "%", text (show op), parens ( commafy $ map pprHinted args ),
- ptext SLIT("returns to"), space, ppr k,
- semi ]
-
-genBranchWithArgs :: (Outputable id, Outputable arg) => id -> [arg] -> SDoc
-genBranchWithArgs ident [] = ptext SLIT("goto") <+> ppr ident <> semi
-genBranchWithArgs ident args = ptext SLIT("goto") <+> ppr ident <+>
- parens (commafy (map ppr args)) <> semi
+pprFun :: CmmExpr -> SDoc
+pprFun f@(CmmLit _) = ppr f
+pprFun f = parens (ppr f)
genFullCondBranch :: Outputable id => CmmExpr -> id -> id -> SDoc
genFullCondBranch expr t f =
- hsep [ ptext SLIT("if")
+ hsep [ ptext (sLit "if")
, parens(ppr expr)
- , ptext SLIT("goto")
+ , ptext (sLit "goto")
, ppr t <> semi
- , ptext SLIT("else goto")
+ , ptext (sLit "else goto")
, ppr f <> semi
]
pprConvention :: Convention -> SDoc
-pprConvention (Argument c) = ppr c
-pprConvention (Result c) = ppr c
-pprConvention Local = text "<local>"
+pprConvention (ConventionStandard c _) = ppr c
+pprConvention (ConventionPrivate {} ) = text "<private-convention>"
commafy :: [SDoc] -> SDoc
commafy xs = hsep $ punctuate comma xs
+
+
+----------------------------------------------------------------
+-- | The purpose of this function is to print a Cmm zipper graph "as if it were"
+-- a Cmm program. The objective is dodgy, so it's unsurprising parts of the
+-- code are dodgy as well.
+
+pprCmmGraphLikeCmm :: CmmGraph -> SDoc
+pprCmmGraphLikeCmm g = vcat (swallow blocks)
+ where blocks = Z.postorder_dfs g
+ swallow :: [CmmBlock] -> [SDoc]
+ swallow [] = []
+ swallow (Z.Block id t : rest) = tail id [] Nothing t rest
+ tail id prev' out (Z.ZTail (CopyOut conv args) t) rest =
+ if isJust out then panic "multiple CopyOut nodes in one basic block"
+ else
+ tail id (prev') (Just (conv, args)) t rest
+ tail id prev' out (Z.ZTail m t) rest = tail id (mid m : prev') out t rest
+ tail id prev' out (Z.ZLast Z.LastExit) rest = exit id prev' out rest
+ tail id prev' out (Z.ZLast (Z.LastOther l)) rest = last id prev' out l rest
+ mid (CopyIn _ [] _) = text "// proc point (no parameters)"
+ mid m@(CopyIn {}) = ppr m <+> text "(proc point)"
+ mid m = ppr m
+ block' id prev'
+ | id == Z.lg_entry g, entry_has_no_pred =
+ vcat (text "<entry>" : reverse prev')
+ | otherwise = hang (ppr id <> colon) 4 (vcat (reverse prev'))
+ last id prev' out l n =
+ let endblock stmt = block' id (stmt : prev') : swallow n in
+ case l of
+ LastBranch tgt ->
+ case n of
+ Z.Block id' t : bs
+ | tgt == id', unique_pred id'
+ -> tail id prev' out t bs -- optimize out redundant labels
+ _ -> endblock (ppr $ CmmBranch tgt)
+ l@(LastCondBranch expr tid fid) ->
+ let ft id = text "// fall through to " <> ppr id in
+ case n of
+ Z.Block id' t : bs
+ | id' == fid, isNothing out ->
+ tail id (ft fid : ppr (CmmCondBranch expr tid) : prev') Nothing t bs
+ | id' == tid, Just e' <- maybeInvertCmmExpr expr, isNothing out->
+ tail id (ft tid : ppr (CmmCondBranch e' fid) : prev') Nothing t bs
+ _ -> endblock $ with_out out l
+ l@(LastJump {}) -> endblock $ with_out out l
+ l@(LastReturn {}) -> endblock $ with_out out l
+ l@(LastSwitch {}) -> endblock $ with_out out l
+ l@(LastCall _ Nothing) -> endblock $ with_out out l
+ l@(LastCall tgt (Just k))
+ | Z.Block id' (Z.ZTail (CopyIn _ ress srt) t) : bs <- n,
+ Just (conv, args) <- out,
+ id' == k ->
+ let call = CmmCall tgt' ress args (CmmSafe srt) CmmMayReturn
+ tgt' = CmmCallee tgt (cconv_of_conv conv)
+ ppcall = ppr call <+> parens (text "ret to" <+> ppr k)
+ in if unique_pred k then
+ tail id (ppcall : prev') Nothing t bs
+ else
+ endblock (ppcall)
+ | Z.Block id' t : bs <- n, id' == k, unique_pred k,
+ Just (conv, args) <- out,
+ Just (ress, srt) <- findCopyIn t ->
+ let call = CmmCall tgt' ress args (CmmSafe srt) CmmMayReturn
+ tgt' = CmmCallee tgt (cconv_of_conv conv)
+ delayed =
+ ptext (sLit "// delayed CopyIn follows previous call")
+ in tail id (delayed : ppr call : prev') Nothing t bs
+ | otherwise -> endblock $ with_out out l
+ findCopyIn (Z.ZTail (CopyIn _ ress srt) _) = Just (ress, srt)
+ findCopyIn (Z.ZTail _ t) = findCopyIn t
+ findCopyIn (Z.ZLast _) = Nothing
+ exit id prev' out n = -- highly irregular (assertion violation?)
+ let endblock stmt = block' id (stmt : prev') : swallow n in
+ case out of Nothing -> endblock (text "// <exit>")
+ Just (conv, args) -> endblock (ppr (CopyOut conv args) $$
+ text "// <exit>")
+ preds = zipPreds g
+ entry_has_no_pred = case lookupBlockEnv preds (Z.lg_entry g) of
+ Nothing -> True
+ Just s -> isEmptyUniqSet s
+ single_preds =
+ let add b single =
+ let id = Z.blockId b
+ in case lookupBlockEnv preds id of
+ Nothing -> single
+ Just s -> if sizeUniqSet s == 1 then
+ extendBlockSet single id
+ else single
+ in Z.fold_blocks add emptyBlockSet g
+ unique_pred id = elemBlockSet id single_preds
+ cconv_of_conv (ConventionStandard conv _) = conv
+ cconv_of_conv (ConventionPrivate {}) = CmmCallConv -- XXX totally bogus
+
+with_out :: Maybe (Convention, CmmActuals) -> Last -> SDoc
+with_out Nothing l = ptext (sLit "??no-arguments??") <+> ppr l
+with_out (Just (conv, args)) l = last l
+ where last (LastCall e k) =
+ hcat [ptext (sLit "... = foreign "),
+ doubleQuotes(ppr conv), space,
+ ppr_target e, parens ( commafy $ map ppr args ),
+ ptext (sLit " \"safe\""),
+ case k of Nothing -> ptext (sLit " never returns")
+ Just _ -> empty,
+ semi ]
+ last (LastReturn) = ppr (CmmReturn args)
+ last (LastJump e) = ppr (CmmJump e args)
+ last l = ppr (CopyOut conv args) $$ ppr l
+ ppr_target (CmmLit lit) = ppr lit
+ ppr_target fn' = parens (ppr fn')
+ commafy xs = hsep $ punctuate comma xs
projects / ghc-hetmet.git / blobdiff