X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2Fspecialise%2FSpecConstr.lhs;h=a2ef2a19b37b22670ba8ab38012c6063b05369a8;hp=d9c611a0ab2d0536af5bcf41cd97c4f433da03f4;hb=707ea5881703d680155aab268bdbf7edc113e3b1;hpb=92267aa26adb1ab5a6d8004a80fdf6aa06ea4e44

diff --git a/compiler/specialise/SpecConstr.lhs b/compiler/specialise/SpecConstr.lhs
index d9c611a..a2ef2a19 100644
--- a/compiler/specialise/SpecConstr.lhs
+++ b/compiler/specialise/SpecConstr.lhs
@@ -11,7 +11,10 @@
 -- for details
 
 module SpecConstr(
-	specConstrProgram, SpecConstrAnnotation(..)
+	specConstrProgram
+#ifdef GHCI
+        , SpecConstrAnnotation(..)
+#endif
     ) where
 
 #include "HsVersions.h"
@@ -24,9 +27,7 @@ import CoreFVs 		( exprsFreeVars )
 import CoreMonad
 import HscTypes         ( ModGuts(..) )
 import WwLib		( mkWorkerArgs )
-import DataCon		( dataConTyCon, dataConRepArity, dataConUnivTyVars )
-import TyCon            ( TyCon )
-import Literal          ( literalType )
+import DataCon
 import Coercion	
 import Rules
 import Type		hiding( substTy )
@@ -51,7 +52,16 @@ import UniqFM
 import MonadUtils
 import Control.Monad	( zipWithM )
 import Data.List
-import Data.Data        ( Data, Typeable )
+
+
+-- See Note [SpecConstrAnnotation]
+#ifndef GHCI
+type SpecConstrAnnotation = ()
+#else
+import Literal          ( literalType )
+import TyCon            ( TyCon )
+import GHC.Exts( SpecConstrAnnotation(..) )
+#endif
 \end{code}
 
 -----------------------------------------------------
@@ -385,6 +395,17 @@ But fspec doesn't have decent strictnes info.  As it happened,
 and hence f.  But now f's strictness is less than its arity, which
 breaks an invariant.
 
+Note [SpecConstrAnnotation]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+SpecConstrAnnotation is defined in GHC.Exts, and is only guaranteed to
+be available in stage 2 (well, until the bootstrap compiler can be
+guaranteed to have it)
+
+So we define it to be () in stage1 (ie when GHCI is undefined), and
+'#ifdef' out the code that uses it.
+
+See also Note [Forcing specialisation]
+
 Note [Forcing specialisation]
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 With stream fusion and in other similar cases, we want to fully specialise
@@ -494,20 +515,6 @@ unbox the strict fields, becuase T is polymorphic!)
 
 %************************************************************************
 %*									*
-\subsection{Annotations}
-%*									*
-%************************************************************************
-
-Annotating a type with NoSpecConstr will make SpecConstr not specialise
-for arguments of that type.
-
-\begin{code}
-data SpecConstrAnnotation = NoSpecConstr | ForceSpecConstr
-                deriving( Data, Typeable, Eq )
-\end{code}
-
-%************************************************************************
-%*									*
 \subsection{Top level wrapper stuff}
 %*									*
 %************************************************************************
@@ -569,6 +576,7 @@ type HowBoundEnv = VarEnv HowBound	-- Domain is OutVars
 ---------------------
 type ValueEnv = IdEnv Value		-- Domain is OutIds
 data Value    = ConVal AltCon [CoreArg]	-- _Saturated_ constructors
+     	      	       	      		--   The AltCon is never DEFAULT
 	      | LambdaVal		-- Inlinable lambdas or PAPs
 
 instance Outputable Value where
@@ -683,22 +691,41 @@ extendCaseBndrs env case_bndr con alt_bndrs
 		       	vanilla_args = map Type (tyConAppArgs (idType case_bndr)) ++
 				       varsToCoreExprs alt_bndrs
 
-ignoreTyCon :: ScEnv -> TyCon -> Bool
-ignoreTyCon env tycon
-  = lookupUFM (sc_annotations env) tycon == Just NoSpecConstr
 
-ignoreType :: ScEnv -> Type -> Bool
+decreaseSpecCount :: ScEnv -> Int -> ScEnv
+-- See Note [Avoiding exponential blowup]
+decreaseSpecCount env n_specs 
+  = env { sc_count = case sc_count env of
+                       Nothing -> Nothing
+                       Just n  -> Just (n `div` (n_specs + 1)) }
+	-- The "+1" takes account of the original function; 
+	-- See Note [Avoiding exponential blowup]
+
+---------------------------------------------------
+-- See Note [SpecConstrAnnotation]
+ignoreType    :: ScEnv -> Type   -> Bool
+ignoreAltCon  :: ScEnv -> AltCon -> Bool
+forceSpecBndr :: ScEnv -> Var    -> Bool
+#ifndef GHCI
+ignoreType    _ _ = False
+ignoreAltCon  _ _ = False
+forceSpecBndr _ _ = False
+
+#else /* GHCI */
+
+ignoreAltCon env (DataAlt dc) = ignoreTyCon env (dataConTyCon dc)
+ignoreAltCon env (LitAlt lit) = ignoreType env (literalType lit)
+ignoreAltCon _   DEFAULT      = panic "ignoreAltCon"  -- DEFAULT cannot be in a ConVal
+
 ignoreType env ty
   = case splitTyConApp_maybe ty of
       Just (tycon, _) -> ignoreTyCon env tycon
       _               -> False
 
-ignoreAltCon :: ScEnv -> AltCon -> Bool
-ignoreAltCon env (DataAlt dc) = ignoreTyCon env (dataConTyCon dc)
-ignoreAltCon env (LitAlt lit) = ignoreType env (literalType lit)
-ignoreAltCon _   DEFAULT      = True
+ignoreTyCon :: ScEnv -> TyCon -> Bool
+ignoreTyCon env tycon
+  = lookupUFM (sc_annotations env) tycon == Just NoSpecConstr
 
-forceSpecBndr :: ScEnv -> Var -> Bool
 forceSpecBndr env var = forceSpecFunTy env . snd . splitForAllTys . varType $ var
 
 forceSpecFunTy :: ScEnv -> Type -> Bool
@@ -715,15 +742,7 @@ forceSpecArgTy env ty
         || any (forceSpecArgTy env) tys
 
 forceSpecArgTy _ _ = False
-
-decreaseSpecCount :: ScEnv -> Int -> ScEnv
--- See Note [Avoiding exponential blowup]
-decreaseSpecCount env n_specs 
-  = env { sc_count = case sc_count env of
-                       Nothing -> Nothing
-                       Just n  -> Just (n `div` (n_specs + 1)) }
-	-- The "+1" takes account of the original function; 
-	-- See Note [Avoiding exponential blowup]
+#endif /* GHCI */
 \end{code}
 
 Note [Avoiding exponential blowup]
@@ -939,13 +958,17 @@ scExpr' env (Let (NonRec bndr rhs) body)
   | isTyCoVar bndr	-- Type-lets may be created by doBeta
   = scExpr' (extendScSubst env bndr rhs) body
 
-  | otherwise		   -- Note [Local let bindings]
+  | otherwise	
   = do	{ let (body_env, bndr') = extendBndr env bndr
-	      body_env2 = extendHowBound body_env [bndr'] RecFun
-	; (body_usg, body') <- scExpr body_env2 body
-
 	; (rhs_usg, rhs_info) <- scRecRhs env (bndr',rhs)
 
+	; let body_env2 = extendHowBound body_env [bndr'] RecFun
+	      			   -- Note [Local let bindings]
+	      RI _ rhs' _ _ _ = rhs_info
+              body_env3 = extendValEnv body_env2 bndr' (isValue (sc_vals env) rhs')
+
+	; (body_usg, body') <- scExpr body_env3 body
+
           -- NB: We don't use the ForceSpecConstr mechanism (see
           -- Note [Forcing specialisation]) for non-recursive bindings
           -- at the moment. I'm not sure if this is the right thing to do.