-{-# 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(..)
)
where
import CmmExpr
import Cmm ( GenCmm(..), GenCmmTop(..), CmmStatic, CmmInfo
- , CmmCallTarget(..), CmmActuals, CmmFormalsWithoutKinds, CmmFormals
- , CmmStmt(CmmJump, CmmSwitch) -- imported in order to call ppr
+ , CmmCallTarget(..), CmmActuals, CmmFormals
+ , CmmStmt(CmmSwitch) -- imported in order to call ppr
)
import PprCmm()
import FastString
import ForeignCall
import MachOp
-import qualified ZipDataflow as DF
+import qualified ZipDataflow0 as DF
import ZipCfg
import MkZipCfg
import Maybes
-import Outputable hiding (empty)
-import qualified Outputable as PP
+import Outputable
import Prelude hiding (zip, unzip, last)
+----------------------------------------------------------------------
+----- Type synonyms and definitions
+
type CmmGraph = LGraph Middle Last
type CmmAGraph = AGraph Middle Last
type CmmBlock = Block Middle Last
type CmmTopZ = GenCmmTop CmmStatic CmmInfo CmmGraph
data Middle
- = MidNop
- | MidComment FastString
+ = MidComment FastString
| MidAssign CmmReg CmmExpr -- Assign to register
| MidUnsafeCall -- An "unsafe" foreign call;
CmmCallTarget -- just a fat machine instructoin
- CmmFormals -- zero or more results
+ 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]'.
- | 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.
-}
+----------------------------------------------------------------------
+----- 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 m = last m
+ 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 UserOfLocalRegs (ZLast Last) where
+ foldRegsUsed f z (LastOther l) = foldRegsUsed f z l
+ foldRegsUsed _f z LastExit = z
+
+
+----------------------------------------------------------------------
+----- Instance declarations for prettyprinting (avoids recursive imports)
instance Outputable Middle where
ppr s = pprMiddle s
instance Outputable CmmGraph where
ppr = pprLgraph
+debugPpr :: Bool
+debugPpr = debugIsOn
+
pprMiddle :: Middle -> SDoc
pprMiddle stmt = (case stmt of
- MidNop -> semi
-
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("...")
CopyOut conv args ->
- if null args then PP.empty
- else ptext SLIT("CopyOut") <+> doubleQuotes(ppr conv) <+>
- parens (commafy (map pprHinted args))
+ ptext SLIT("next, pass") <+> doubleQuotes(ppr conv) <+>
+ parens (commafy (map pprHinted args))
-- // text
MidComment s -> text "//" <+> ftext s
-- ToDo ppr volatile
MidUnsafeCall (CmmCallee fn cconv) results args ->
hcat [ if null results
- then PP.empty
+ then empty
else parens (commafy $ map ppr results) <>
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)
- ) <+> 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 ]
+
+ ) <>
+ if 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')
pprHinted :: Outputable a => (a, MachHint) -> SDoc
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
- ) <+> text "//" <+>
- case stmt of
- LastBranch {} -> text "LastBranch"
- LastCondBranch {} -> text "LastCondBranch"
- LastJump {} -> text "LastJump"
- LastReturn {} -> text "LastReturn"
- 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
+ LastCall tgt k -> genBareCall tgt k
+ ) <>
+ if debugPpr then empty
+ else 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 =
+ 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 =
]
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