-
-
-- This module is pure representation and should be imported only by
-- clients that need to manipulate representation and know what
-- they're doing. Clients that need to create flow graphs should
module ZipCfgCmmRep
( CmmZ, CmmTopZ, CmmGraph, CmmBlock, CmmAGraph
- , Middle(..), Last(..), MidCallTarget(..)
- , Convention(..), ForeignConvention(..)
+ , Middle(..), Last(..), MidCallTarget(..), UpdFrameOffset
+ , Convention(..), ForeignConvention(..), ForeignSafety(..)
, ValueDirection(..), ForeignHint(..)
, CmmBackwardFixedPoint, CmmForwardFixedPoint, pprHinted
, insertBetween, mapExpMiddle, mapExpLast, mapExpDeepMiddle, mapExpDeepLast
- , foldExpMiddle, foldExpLast, foldExpDeepMiddle, foldExpDeepLast
- , joinOuts
+ , foldExpMiddle, foldExpLast, foldExpDeepMiddle, foldExpDeepLast, joinOuts
)
where
import MkZipCfg
import Util
+import BasicTypes
import Maybes
import Monad
import Outputable
import Prelude hiding (zip, unzip, last)
import qualified Data.List as L
+import SMRep (ByteOff)
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 CmmStackInfo = (ByteOff, Maybe ByteOff)
+ -- probably want a record; (SP offset on entry, update frame space)
+type CmmZ = GenCmm CmmStatic CmmInfo (CmmStackInfo, CmmGraph)
+type CmmTopZ = GenCmmTop CmmStatic CmmInfo (CmmStackInfo, CmmGraph)
type CmmBackwardFixedPoint a = DF.BackwardFixedPoint Middle Last a ()
type CmmForwardFixedPoint a = DF.ForwardFixedPoint Middle Last a ()
+type UpdFrameOffset = ByteOff
+
data Middle
= MidComment FastString
| MidStore CmmExpr CmmExpr -- Assign to memory location. Size is
-- given by cmmExprType of the rhs.
- | MidUnsafeCall -- An "unsafe" foreign call;
- MidCallTarget -- just a fat machine instructoin
+ | MidForeignCall -- A foreign call; see Note [Foreign calls]
+ ForeignSafety -- Is it a safe or unsafe call?
+ MidCallTarget -- call target and convention
CmmFormals -- zero or more results
CmmActuals -- zero or more arguments
-
- | 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
deriving Eq
data Last
-- zero -> first block
-- one -> second block etc
-- Undefined outside range, and when there's a Nothing
- | LastReturn Int -- Return from a function; values in previous copy middles
- | LastJump CmmExpr Int -- Tail call to another procedure; args in a copy middles
- | LastCall { -- A call (native or safe foreign); args in copy middles
- cml_target :: CmmExpr, -- never a CmmPrim to a CallishMachOp!
- cml_cont :: Maybe BlockId,-- BlockId of continuation, if call returns
- cml_args :: Int } -- liveness info for outgoing args
- -- All the last nodes that pass arguments carry the size of the outgoing CallArea
+ | LastCall { -- A call (native or safe foreign)
+ cml_target :: CmmExpr, -- never a CmmPrim to a CallishMachOp!
+ cml_cont :: Maybe BlockId,
+ -- BlockId of continuation (Nothing for return or tail call)
+ cml_args :: ByteOff, -- byte offset for youngest outgoing arg
+ -- (includes update frame, which must be younger)
+ cml_ret_args:: ByteOff, -- byte offset for youngest incoming arg
+ cml_ret_off :: Maybe UpdFrameOffset}
+ -- stack offset for return (update frames);
+ -- The return offset should be Nothing only if we have to create
+ -- a new call, e.g. for a procpoint, in which case it's an invariant
+ -- that the call does not stand for a return or a tail call,
+ -- and the successor does not need an info table.
data MidCallTarget -- The target of a MidUnsafeCall
= ForeignTarget -- A foreign procedure
deriving Eq
data Convention
- = Native -- Native C-- call/return
+ = NativeDirectCall -- Native C-- call skipping the node (closure) argument
+
+ | NativeNodeCall -- Native C-- call including the node argument
+
+ | NativeReturn -- Native C-- return
+
+ | Slow -- Slow entry points: all args pushed on the stack
+
+ | GC -- Entry to the garbage collector: uses the node reg!
+
+ | PrimOpCall -- Calling prim ops
- | Foreign -- Foreign call/return
- ForeignConvention
+ | PrimOpReturn -- Returning from prim ops
+
+ | Foreign -- Foreign call/return
+ ForeignConvention
| Private
-- Used for control transfers within a (pre-CPS) procedure All
[ForeignHint] -- Extra info about the result
deriving Eq
+data ForeignSafety
+ = Unsafe -- unsafe call
+ | Safe BlockId -- making infotable requires: 1. label
+ UpdFrameOffset -- 2. where the upd frame is
+ deriving Eq
+
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 [Foreign calls]
+~~~~~~~~~~~~~~~~~~~~~~~
+A MidForeign call is used *all* foreign calls, both *unsafe* and *safe*.
+Unsafe ones are easy: think of them as a "fat machine instruction".
+
+Safe ones are trickier. A safe foreign call
+ r = f(x)
+ultimately expands to
+ push "return address" -- Never used to return to;
+ -- just points an info table
+ save registers into TSO
+ call suspendThread
+ r = f(x) -- Make the call
+ call resumeThread
+ restore registers
+ pop "return address"
+We cannot "lower" a safe foreign call to this sequence of Cmms, because
+after we've saved Sp all the Cmm optimiser's assumptions are broken.
+Furthermore, currently the smart Cmm constructors know the calling
+conventions for Haskell, the garbage collector, etc, and "lower" them
+so that a LastCall passes no parameters or results. But the smart
+constructors do *not* (currently) know the foreign call conventions.
+
+For these reasons use MidForeignCall for all calls. The only annoying thing
+is that a safe foreign call needs an info table.
+-}
----------------------------------------------------------------------
----- Splicing between blocks
insert (h, LastOther (LastSwitch e ks)) =
do (ids, bs) <- mapAndUnzipM mbNewBlocks ks
return (zipht h $ ZLast $ LastOther (LastSwitch e ids), join bs)
- insert (_, LastOther (LastCall _ _ _)) =
+ insert (_, LastOther (LastCall {})) =
panic "unimp: insertBetween after a call -- probably not a good idea"
- 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 Nothing $
+ 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, [])
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 (LastBranch id) = [id]
+cmmSuccs (LastCall _ Nothing _ _ _) = []
+cmmSuccs (LastCall _ (Just id) _ _ _) = [id]
+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 (LastCondBranch _ te fe) z = f te (f fe z)
-fold_cmm_succs f (LastSwitch _ edges) z = foldl (flip f) z $ catMaybes edges
+fold_cmm_succs f (LastBranch id) z = f id z
+fold_cmm_succs _ (LastCall _ Nothing _ _ _) z = z
+fold_cmm_succs f (LastCall _ (Just id) _ _ _) z = f id 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
----------------------------------------------------------------------
----- 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 _ args) = fold f (fold f z tgt) args
- middle (MidAddToContext ra args) = fold f (fold f z ra) args
+ where middle (MidComment {}) = z
+ middle (MidAssign _lhs expr) = fold f z expr
+ middle (MidStore addr rval) = fold f (fold f z addr) rval
+ middle (MidForeignCall _ tgt _ args) = fold f (fold f z tgt) args
fold f z m = foldRegsUsed f z m -- avoid monomorphism restriction
instance UserOfLocalRegs MidCallTarget where
foldSlotsUsed _f z (PrimTarget _) = z
foldSlotsUsed f z (ForeignTarget e _) = foldSlotsUsed f z e
+instance (UserOfLocalRegs a) => UserOfLocalRegs (Maybe a) where
+ foldRegsUsed f z (Just x) = foldRegsUsed f z x
+ foldRegsUsed _ z Nothing = z
+
+instance (UserOfSlots a) => UserOfSlots (Maybe a) where
+ foldSlotsUsed f z (Just x) = foldSlotsUsed f z x
+ foldSlotsUsed _ z Nothing = z
+
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
+ where 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
+ where middle (MidComment {}) = z
+ middle (MidAssign lhs _) = fold f z lhs
+ middle (MidStore _ _) = z
+ middle (MidForeignCall _ _ fs _) = fold f z fs
fold f z m = foldRegsDefd f z m -- avoid monomorphism restriction
instance DefinerOfLocalRegs Last where
instance UserOfSlots Middle where
foldSlotsUsed 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
+ where middle (MidComment {}) = z
+ middle (MidAssign _lhs expr) = fold f z expr
+ middle (MidStore addr rval) = fold f (fold f z addr) rval
+ middle (MidForeignCall _ tgt _ress args) = fold f (fold f z tgt) args
fold f z e = foldSlotsUsed f z e -- avoid monomorphism restriction
instance UserOfSlots Last where
foldSlotsUsed f z l = last l
- where last (LastReturn _) = z
- last (LastJump e _) = foldSlotsUsed f z e
- last (LastBranch _id) = z
- last (LastCall tgt _ _) = foldSlotsUsed f z tgt
+ where last (LastBranch _id) = z
+ last (LastCall tgt _ _ _ _) = foldSlotsUsed f z tgt
last (LastCondBranch e _ _) = foldSlotsUsed f z e
last (LastSwitch e _tbl) = foldSlotsUsed f z e
instance DefinerOfSlots Middle where
foldSlotsDefd f z m = middle m
- where middle (MidComment {}) = z
- middle (MidAssign _ _) = z
+ where middle (MidComment {}) = z
+ middle (MidAssign _ _) = z
+ middle (MidForeignCall {}) = z
middle (MidStore (CmmStackSlot a i) e) =
f z (a, i, widthInBytes $ typeWidth $ cmmExprType e)
- middle (MidStore _ _) = z
- middle (MidUnsafeCall _ _ _) = z
- middle (MidAddToContext _ _) = z
+ middle (MidStore _ _) = z
instance DefinerOfSlots Last where
foldSlotsDefd _ z _ = z
mapExpMiddle _ m@(MidComment _) = m
mapExpMiddle exp (MidAssign r e) = MidAssign r (exp e)
mapExpMiddle exp (MidStore addr e) = MidStore (exp addr) (exp e)
-mapExpMiddle exp (MidUnsafeCall tgt fs as) =
- MidUnsafeCall (mapExpMidcall exp tgt) fs (map exp as)
-mapExpMiddle exp (MidAddToContext e es) = MidAddToContext (exp e) (map exp es)
+mapExpMiddle exp (MidForeignCall s tgt fs as) =
+ MidForeignCall s (mapExpMidcall exp tgt) fs (map exp as)
foldExpMiddle :: (CmmExpr -> z -> z) -> Middle -> z -> z
-foldExpMiddle _ (MidComment _) z = z
-foldExpMiddle exp (MidAssign _ e) z = exp e z
-foldExpMiddle exp (MidStore addr e) z = exp addr $ exp e z
-foldExpMiddle exp (MidUnsafeCall tgt _ as) z = foldExpMidcall exp tgt $ foldr exp z as
-foldExpMiddle exp (MidAddToContext e es) z = exp e $ foldr exp z es
+foldExpMiddle _ (MidComment _) z = z
+foldExpMiddle exp (MidAssign _ e) z = exp e z
+foldExpMiddle exp (MidStore addr e) z = exp addr $ exp e z
+foldExpMiddle exp (MidForeignCall _ tgt _ as) z = foldExpMidcall exp tgt $ foldr exp z as
mapExpLast :: (CmmExpr -> CmmExpr) -> Last -> Last
-mapExpLast _ l@(LastBranch _) = l
-mapExpLast exp (LastCondBranch e ti fi) = LastCondBranch (exp e) ti fi
-mapExpLast exp (LastSwitch e tbl) = LastSwitch (exp e) tbl
-mapExpLast exp (LastCall tgt mb_id s) = LastCall (exp tgt) mb_id s
-mapExpLast exp (LastJump e s) = LastJump (exp e) s
-mapExpLast _ (LastReturn s) = LastReturn s
+mapExpLast _ l@(LastBranch _) = l
+mapExpLast exp (LastCondBranch e ti fi) = LastCondBranch (exp e) ti fi
+mapExpLast exp (LastSwitch e tbl) = LastSwitch (exp e) tbl
+mapExpLast exp (LastCall tgt mb_id o i s) = LastCall (exp tgt) mb_id o i s
foldExpLast :: (CmmExpr -> z -> z) -> Last -> z -> z
foldExpLast _ (LastBranch _) z = z
foldExpLast exp (LastCondBranch e _ _) z = exp e z
foldExpLast exp (LastSwitch e _) z = exp e z
-foldExpLast exp (LastCall tgt _ _) z = exp tgt z
-foldExpLast exp (LastJump e _) z = exp e z
-foldExpLast _ (LastReturn _) z = z
+foldExpLast exp (LastCall tgt _ _ _ _) z = exp tgt z
mapExpMidcall :: (CmmExpr -> CmmExpr) -> MidCallTarget -> MidCallTarget
mapExpMidcall exp (ForeignTarget e c) = ForeignTarget (exp e) c
-- Take a transformer on expressions and apply it recursively.
wrapRecExp :: (CmmExpr -> CmmExpr) -> CmmExpr -> CmmExpr
-wrapRecExp f (CmmMachOp op es) = f (CmmMachOp op $ map f es)
-wrapRecExp f (CmmLoad addr ty) = f (CmmLoad (f addr) ty)
+wrapRecExp f (CmmMachOp op es) = f (CmmMachOp op $ map (wrapRecExp f) es)
+wrapRecExp f (CmmLoad addr ty) = f (CmmLoad (wrapRecExp f addr) ty)
wrapRecExp f e = f e
mapExpDeepMiddle :: (CmmExpr -> CmmExpr) -> Middle -> Middle
-- Take a folder on expressions and apply it recursively.
wrapRecExpf :: (CmmExpr -> z -> z) -> CmmExpr -> z -> z
-wrapRecExpf f e@(CmmMachOp _ es) z = foldr f (f e z) es
-wrapRecExpf f e@(CmmLoad addr _) z = f addr (f e z)
+wrapRecExpf f e@(CmmMachOp _ es) z = foldr (wrapRecExpf f) (f e z) es
+wrapRecExpf f e@(CmmLoad addr _) z = wrapRecExpf f addr (f e z)
wrapRecExpf f e z = f e z
foldExpDeepMiddle :: (CmmExpr -> z -> z) -> Middle -> z -> z
let bot = fact_bot lattice
join x y = txVal $ fact_add_to lattice x y
in case l of
- (LastReturn _) -> bot
- (LastJump _ _) -> bot
- (LastBranch id) -> env id
- (LastCall _ Nothing _) -> bot
- (LastCall _ (Just k) _) -> env k
- (LastCondBranch _ t f) -> join (env t) (env f)
- (LastSwitch _ tbl) -> foldr join bot (map env $ catMaybes tbl)
+ (LastBranch id) -> env id
+ (LastCall _ Nothing _ _ _) -> bot
+ (LastCall _ (Just k) _ _ _) -> env k
+ (LastCondBranch _ t f) -> join (env t) (env f)
+ (LastSwitch _ tbl) -> foldr join bot (map env $ catMaybes tbl)
----------------------------------------------------------------------
----- Instance declarations for prettyprinting (avoids recursive imports)
-- call "ccall" foo(x, y)[r1, r2];
-- ToDo ppr volatile
- MidUnsafeCall target results args ->
+ MidForeignCall safety target results args ->
hsep [ if null results
then empty
else parens (commafy $ map ppr results) <+> equals,
+ ppr_safety safety,
ptext $ sLit "call",
ppr_call_target target <> parens (commafy $ map ppr args) <> semi]
- MidAddToContext ra args ->
- hcat [ ptext $ sLit "return via "
- , ppr_target ra, parens (commafy $ map ppr args), semi ]
-
pp_debug =
if not debugPpr then empty
else text " //" <+>
case stmt of
- MidComment {} -> text "MidComment"
- MidAssign {} -> text "MidAssign"
- MidStore {} -> text "MidStore"
- MidUnsafeCall {} -> text "MidUnsafeCall"
- MidAddToContext {} -> text "MidAddToContext"
+ MidComment {} -> text "MidComment"
+ MidAssign {} -> text "MidAssign"
+ MidStore {} -> text "MidStore"
+ MidForeignCall {} -> text "MidForeignCall"
ppr_fc :: ForeignConvention -> SDoc
-ppr_fc (ForeignConvention c _ _) = doubleQuotes (ppr c)
+ppr_fc (ForeignConvention c args res) =
+ doubleQuotes (ppr c) <+> text "args: " <+> ppr args <+> text " results: " <+> ppr res
+
+ppr_safety :: ForeignSafety -> SDoc
+ppr_safety (Safe bid upd) = text "safe<" <> ppr bid <> text ", " <> ppr upd <> text ">"
+ppr_safety Unsafe = text "unsafe"
ppr_call_target :: MidCallTarget -> SDoc
ppr_call_target (ForeignTarget fn c) = ppr_fc c <+> ppr_target fn
-ppr_call_target (PrimTarget op) = ppr (CmmLabel (mkForeignLabel (mkFastString (show op)) Nothing False))
+ppr_call_target (PrimTarget op) = ppr (CmmLabel (mkForeignLabel (mkFastString (show op)) Nothing False IsFunction))
ppr_target :: CmmExpr -> SDoc
ppr_target t@(CmmLit _) = ppr t
pprLast stmt = pp_stmt <+> pp_debug
where
pp_stmt = case stmt of
- LastBranch ident -> ptext (sLit "goto") <+> ppr ident <> semi
- LastCondBranch expr t f -> genFullCondBranch expr t f
- 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 k _ -> genBareCall tgt k
+ LastBranch ident -> ptext (sLit "goto") <+> ppr ident <> semi
+ LastCondBranch expr t f -> genFullCondBranch expr t f
+ LastSwitch arg ids -> ppr $ CmmSwitch arg ids
+ LastCall tgt k out res updfr_off -> genBareCall tgt k out res updfr_off
pp_debug = text " //" <+> case stmt of
LastBranch {} -> text "LastBranch"
LastCondBranch {} -> text "LastCondBranch"
- LastJump {} -> text "LastJump"
- LastReturn {} -> text "LastReturn"
LastSwitch {} -> text "LastSwitch"
LastCall {} -> text "LastCall"
-genBareCall :: CmmExpr -> Maybe BlockId -> SDoc
-genBareCall fn k =
+genBareCall :: CmmExpr -> Maybe BlockId -> ByteOff -> ByteOff ->
+ Maybe UpdFrameOffset -> SDoc
+genBareCall fn k out res updfr_off =
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
+ , ptext (sLit "returns to") <+> ppr k <+> parens (ppr out)
+ <+> parens (ppr res)
+ , ptext (sLit " with update frame") <+> ppr updfr_off
, semi ]
- where
pprFun :: CmmExpr -> SDoc
pprFun f@(CmmLit _) = ppr f
]
pprConvention :: Convention -> SDoc
-pprConvention (Native {}) = empty
-pprConvention (Foreign c) = ppr c
-pprConvention (Private {}) = text "<private-convention>"
+pprConvention (NativeNodeCall {}) = text "<native-node-call-convention>"
+pprConvention (NativeDirectCall {}) = text "<native-direct-call-convention>"
+pprConvention (NativeReturn {}) = text "<native-ret-convention>"
+pprConvention Slow = text "<slow-convention>"
+pprConvention GC = text "<gc-convention>"
+pprConvention PrimOpCall = text "<primop-call-convention>"
+pprConvention PrimOpReturn = text "<primop-ret-convention>"
+pprConvention (Foreign c) = ppr c
+pprConvention (Private {}) = text "<private-convention>"
pprForeignConvention :: ForeignConvention -> SDoc
pprForeignConvention (ForeignConvention c as rs) = ppr c <> ppr as <> ppr rs