X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Fspecialise%2FSpecialise.lhs;h=037db7a71deb02ecbd35345811c5101fd3645e9d;hb=22b34988e2b156593d7cfc9b72d6cc0ab471a1d2;hp=4d8efdd8c5c2c55dae5cf832fb3f16af9c5906cc;hpb=e79c9ce01d0ce4412bd4bcd99c8c728a6a2ec569;p=ghc-hetmet.git

diff --git a/compiler/specialise/Specialise.lhs b/compiler/specialise/Specialise.lhs
index 4d8efdd..037db7a 100644
--- a/compiler/specialise/Specialise.lhs
+++ b/compiler/specialise/Specialise.lhs
@@ -15,8 +15,8 @@ module Specialise ( specProgram ) where
 #include "HsVersions.h"
 
 import Id		( Id, idName, idType, mkUserLocal, idCoreRules,
-			  idInlinePragma, setInlinePragma, setIdUnfolding,
-			  isLocalId ) 
+			  idInlineActivation, setInlineActivation, setIdUnfolding,
+                          isLocalId, idArity, setIdArity ) 
 import TcType		( Type, mkTyVarTy, tcSplitSigmaTy, 
 			  tyVarsOfTypes, tyVarsOfTheta, isClassPred,
 			  tcCmpType, isUnLiftedType
@@ -826,10 +826,11 @@ specDefn subst calls fn rhs
   
   where
     fn_type	       = idType fn
+    fn_arity	       = idArity fn
     (tyvars, theta, _) = tcSplitSigmaTy fn_type
     n_tyvars	       = length tyvars
     n_dicts	       = length theta
-    inline_prag        = idInlinePragma fn
+    inline_act         = idInlineActivation fn
 
 	-- It's important that we "see past" any INLINE pragma
 	-- else we'll fail to specialise an INLINE thing
@@ -906,6 +907,10 @@ specDefn subst calls fn rhs
 	         spec_id_ty = mkPiTypes lam_args body_ty
 	
            ; spec_f <- newSpecIdSM fn spec_id_ty
+  	   ; let spec_f_w_arity = setIdArity spec_f (max 0 (fn_arity - n_dicts))
+		-- Adding arity information just propagates it a bit faster
+		-- See Note [Arity decrease] in Simplify
+
            ; (spec_rhs, rhs_uds) <- specExpr rhs_subst2 (mkLams lam_args body)
 	   ; let
 		-- The rule to put in the function's specialisation is:
@@ -913,17 +918,17 @@ specDefn subst calls fn rhs
 	        rule_name = mkFastString ("SPEC " ++ showSDoc (ppr fn <+> ppr spec_ty_args))
   		spec_env_rule = mkLocalRule
 			          rule_name
-				  inline_prag 	-- Note [Auto-specialisation and RULES]
+				  inline_act 	-- Note [Auto-specialisation and RULES]
 			 	  (idName fn)
 			          (poly_tyvars ++ inst_dict_ids)
 				  inst_args 
-				  (mkVarApps (Var spec_f) app_args)
+				  (mkVarApps (Var spec_f_w_arity) app_args)
 
 		-- Add the { d1' = dx1; d2' = dx2 } usage stuff
 	   	final_uds = foldr addDictBind rhs_uds dx_binds
 
-	   	spec_pr | inline_rhs = (spec_f `setInlinePragma` inline_prag, Note InlineMe spec_rhs)
-		        | otherwise  = (spec_f, 		 	      spec_rhs)
+	   	spec_pr | inline_rhs = (spec_f_w_arity `setInlineActivation` inline_act, Note InlineMe spec_rhs)
+		        | otherwise  = (spec_f_w_arity, 	 	                 spec_rhs)
 
 	   ; return (Just (spec_pr, final_uds, spec_env_rule)) } }
       where
@@ -1068,7 +1073,8 @@ Note [Inline specialisations]
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 We transfer to the specialised function any INLINE stuff from the
 original.  This means (a) the Activation in the IdInfo, and (b) any
-InlineMe on the RHS.  
+InlineMe on the RHS.  We do not, however, transfer the RuleMatchInfo
+since we do not expect the specialisation to occur in rewrite rules.
 
 This is a change (Jun06).  Previously the idea is that the point of
 inlining was precisely to specialise the function at its call site,