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[ghc-hetmet.git] / compiler / cmm / ZipCfgCmmRep.hs

diff --git a/compiler/cmm/ZipCfgCmmRep.hs b/compiler/cmm/ZipCfgCmmRep.hs
index 71e206e..d4ed3cf 100644 (file)
--- a/compiler/cmm/ZipCfgCmmRep.hs
+++ b/compiler/cmm/ZipCfgCmmRep.hs
@@ -1,4 +1,4 @@
-{-# 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
 
 -- This module is pure representation and should be imported only by
 -- clients that need to manipulate representation and know what

@@ -7,6 +7,7 @@
 
 module ZipCfgCmmRep
   ( CmmZ, CmmTopZ, CmmGraph, CmmBlock, CmmAGraph, Middle(..), Last(..), Convention(..)
 
 module ZipCfgCmmRep
   ( CmmZ, CmmTopZ, CmmGraph, CmmBlock, CmmAGraph, Middle(..), Last(..), Convention(..)

+  , ValueDirection(..)

   )
 where
 
   )
 where
 

@@ -14,8 +15,8 @@ where
 
 import CmmExpr
 import Cmm ( GenCmm(..), GenCmmTop(..), CmmStatic, CmmInfo
 
 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 PprCmm()
 

@@ -29,10 +30,12 @@ import ZipCfg
 import MkZipCfg
 
 import Maybes
 import MkZipCfg
 
 import Maybes

-import Outputable hiding (empty)
-import qualified Outputable as PP
+import Outputable

 import Prelude hiding (zip, unzip, last)
 
 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 CmmGraph  = LGraph Middle Last
 type CmmAGraph = AGraph Middle Last
 type CmmBlock  = Block  Middle Last

@@ -50,37 +53,41 @@ data Middle
 
   | MidUnsafeCall                -- An "unsafe" foreign call;
      CmmCallTarget               -- just a fat machine instructoin
 
   | 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
 
      CmmActuals                  -- zero or more arguments
 

-  | CopyIn    -- Move parameters or results from conventional locations to registers
-              -- Note [CopyIn invariant]
+  | CopyIn    -- Move incoming parameters or results from conventional
+              -- locations to registers.  Note [CopyIn invariant]

         Convention 
         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
         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
+  | 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]'.

 
 

-  | LastBranch BlockId CmmFormalsWithoutKinds
-        -- To another block in the same procedure
-        -- The parameters are unused at present.
-
-  | 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
     }
 
 
   | 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
   | LastSwitch CmmExpr [Maybe BlockId]   -- Table branch
         -- The scrutinee is zero-based; 
         --      zero -> first block

@@ -88,62 +95,66 @@ data Last
         -- Undefined outside range, and when there's a Nothing
 
 data Convention
         -- 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
 
   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]
 ~~~~~~~~~~~~~~~~~~~~~~~
 
 {-
 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
 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
 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
     isBranchNode _ = False

-    branchNodeTarget (LastBranch id []) = id
+    branchNodeTarget (LastBranch id) = id

     branchNodeTarget _ = panic "asked for target of non-branch"
 
 cmmSuccs :: Last -> [BlockId]
     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 :: (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
 
 
 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 prettyprinting (avoids recursive imports)

 
 instance Outputable Middle where
     ppr s = pprMiddle s
 
 instance Outputable Middle where
     ppr s = pprMiddle s

@@ -157,12 +168,10 @@ instance Outputable Convention where
 instance DF.DebugNodes Middle Last
 
 instance Outputable CmmGraph where
 instance DF.DebugNodes Middle Last
 
 instance Outputable CmmGraph where

-    ppr = pprCmmGraphAsRep
+    ppr = pprLgraph

 
 

-pprCmmGraphAsRep :: CmmGraph -> SDoc
-pprCmmGraphAsRep g = vcat (map ppr_block blocks)
-    where blocks = postorder_dfs g
-          ppr_block (Block id tail) = hang (ppr id <> colon) 4 (ppr tail)
+debugPpr :: Bool
+debugPpr = debugIsOn

 
 pprMiddle :: Middle -> SDoc    
 pprMiddle stmt = (case stmt of
 
 pprMiddle :: Middle -> SDoc    
 pprMiddle stmt = (case stmt of

@@ -175,9 +184,8 @@ pprMiddle stmt = (case stmt of
              ptext SLIT("foreign") <+> doubleQuotes(ppr conv) <+> ptext SLIT("...")
 
     CopyOut conv args ->
              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
 
     --  // text
     MidComment s -> text "//" <+> ftext s

@@ -194,7 +202,7 @@ pprMiddle stmt = (case stmt of
     -- ToDo ppr volatile
     MidUnsafeCall (CmmCallee fn cconv) results args ->
         hcat [ if null results
     -- 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, 
                   else parens (commafy $ map ppr results) <>
                        ptext SLIT(" = "),
                ptext SLIT("call"), space, 

@@ -209,15 +217,17 @@ pprMiddle stmt = (case stmt of
         pprMiddle (MidUnsafeCall (CmmCallee (CmmLit lbl) CCallConv) results args)
         where
           lbl = CmmLabel (mkForeignLabel (mkFastString (show op)) Nothing False)
         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"
+  ) <>
+  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"

 
 
 pprHinted :: Outputable a => (a, MachHint) -> SDoc
 
 
 pprHinted :: Outputable a => (a, MachHint) -> SDoc

@@ -228,45 +238,37 @@ pprHinted (a, FloatHint)  = doubleQuotes (text "float")   <+> ppr a
 
 pprLast :: Last -> SDoc    
 pprLast stmt = (case stmt of
 
 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
     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
     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
              , 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 =
 
 genFullCondBranch :: Outputable id => CmmExpr -> id -> id -> SDoc
 genFullCondBranch expr t f =

@@ -279,9 +281,8 @@ genFullCondBranch expr t f =
          ]
 
 pprConvention :: Convention -> SDoc
          ]
 
 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
 
 commafy :: [SDoc] -> SDoc
 commafy xs = hsep $ punctuate comma xs