Remove the (very) old strictness analyser

[ghc-hetmet.git] / compiler / stranal / WorkWrap.lhs

diff --git a/compiler/stranal/WorkWrap.lhs b/compiler/stranal/WorkWrap.lhs
index 772a862..4e7a494 100644 (file)
--- a/compiler/stranal/WorkWrap.lhs
+++ b/compiler/stranal/WorkWrap.lhs
@@ -7,22 +7,20 @@
 module WorkWrap ( wwTopBinds, mkWrapper ) where
 
 import CoreSyn
-import CoreUnfold      ( certainlyWillInline )
-import CoreUtils       ( exprType, exprIsHNF, mkInlineMe )
+import CoreUnfold      ( certainlyWillInline, mkInlineRule, mkWwInlineRule )
+import CoreUtils       ( exprType, exprIsHNF )
 import CoreArity       ( exprArity )
 import Var
-import Id              ( Id, idType, isOneShotLambda, idUnfolding,
-                         setIdNewStrictness, mkWorkerId,
-                         setIdWorkerInfo, setInlineActivation,
-                         setIdArity, idInfo )
-import MkId            ( lazyIdKey, lazyIdUnfolding )
+import Id              ( idType, isOneShotLambda, idUnfolding,
+                         setIdStrictness, mkWorkerId,
+                         setInlineActivation, setIdUnfolding,
+                         setIdArity )
 import Type            ( Type )
 import IdInfo
-import NewDemand        ( Demand(..), StrictSig(..), DmdType(..), DmdResult(..), 
+import Demand           ( Demand(..), StrictSig(..), DmdType(..), DmdResult(..), 
                          Demands(..), mkTopDmdType, isBotRes, returnsCPR, topSig, isAbsent
                        )
 import UniqSupply
-import Unique          ( hasKey )
 import BasicTypes      ( RecFlag(..), isNonRec, isNeverActive,
                           Activation, inlinePragmaActivation )
 import VarEnv          ( isEmptyVarEnv )
@@ -107,16 +105,9 @@ matching by looking for strict arguments of the correct type.
 \begin{code}
 wwExpr :: CoreExpr -> UniqSM CoreExpr
 
-wwExpr e@(Type _)          = return e
-wwExpr e@(Lit _)           = return e
-wwExpr e@(Note InlineMe _) = return e
-       -- Don't w/w inside InlineMe's
-
-wwExpr e@(Var v)
-  | v `hasKey` lazyIdKey = return lazyIdUnfolding
-  | otherwise            = return e
-       -- HACK alert: Inline 'lazy' after strictness analysis
-       -- (but not inside InlineMe's)
+wwExpr e@(Type {}) = return e
+wwExpr e@(Lit  {}) = return e
+wwExpr e@(Var  {}) = return e
 
 wwExpr (Lam binder expr)
   = Lam binder <$> wwExpr expr
@@ -165,7 +156,10 @@ The only reason this is monadised is for the unique supply.
 Note [Don't w/w inline things (a)]
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 It's very important to refrain from w/w-ing an INLINE function
-If we do so by mistake we transform
+because the wrapepr will then overwrite the InlineRule unfolding.
+
+It was wrong with the old InlineMe Note too: if we do so by mistake 
+we transform
        f = __inline (\x -> E)
 into
        f = __inline (\x -> case x of (a,b) -> fw E)
@@ -231,12 +225,12 @@ tryWW is_rec fn_id rhs
 
   where
     fn_info     = idInfo fn_id
-    maybe_fn_dmd = newDemandInfo fn_info
+    maybe_fn_dmd = demandInfo fn_info
     inline_act   = inlinePragmaActivation (inlinePragInfo fn_info)
 
        -- In practice it always will have a strictness 
        -- signature, even if it's a uninformative one
-    strict_sig  = newStrictnessInfo fn_info `orElse` topSig
+    strict_sig  = strictnessInfo fn_info `orElse` topSig
     StrictSig (DmdType env wrap_dmds res_info) = strict_sig
 
        -- new_fn_id has the DmdEnv zapped.  
@@ -245,21 +239,29 @@ tryWW is_rec fn_id rhs
        --      (c) it becomes incorrect as things are cloned, because
        --          we don't push the substitution into it
     new_fn_id | isEmptyVarEnv env = fn_id
-             | otherwise         = fn_id `setIdNewStrictness` 
+             | otherwise         = fn_id `setIdStrictness` 
                                     StrictSig (mkTopDmdType wrap_dmds res_info)
 
     is_fun    = notNull wrap_dmds
     is_thunk  = not is_fun && not (exprIsHNF rhs)
 
 ---------------------
-checkSize :: Id -> CoreExpr -> UniqSM [(Id,CoreExpr)] -> UniqSM [(Id,CoreExpr)]
+checkSize :: Id -> CoreExpr
+         -> UniqSM [(Id,CoreExpr)] -> UniqSM [(Id,CoreExpr)]
  -- See Note [Don't w/w inline things (a) and (b)]
 checkSize fn_id rhs thing_inside
-  | certainlyWillInline unfolding = return [ (fn_id, mkInlineMe rhs) ]
+  | isStableUnfolding unfolding           -- For DFuns and INLINE things, leave their
+  = return [ (fn_id, rhs) ]       -- unfolding unchanged; but still attach 
+                                  -- strictness info to the Id 
+
+  | certainlyWillInline unfolding
+  = return [ (fn_id `setIdUnfolding` inline_rule, rhs) ]
                -- Note [Don't w/w inline things (b)]
+
   | otherwise = thing_inside
   where
     unfolding = idUnfolding fn_id
+    inline_rule = mkInlineRule InlUnSat rhs (unfoldingArity unfolding)
 
 ---------------------
 splitFun :: Id -> IdInfo -> [Demand] -> DmdResult -> Activation -> Expr Var
@@ -281,7 +283,7 @@ splitFun fn_id fn_info wrap_dmds res_info inline_act rhs
                                -- can't think of a compelling reason. (In ptic, INLINE things are 
                                -- not w/wd). However, the RuleMatchInfo is not transferred since
                                 -- it does not make sense for workers to be constructorlike.
-                       `setIdNewStrictness` StrictSig (mkTopDmdType work_demands work_res_info)
+                       `setIdStrictness` StrictSig (mkTopDmdType work_demands work_res_info)
                                -- Even though we may not be at top level, 
                                -- it's ok to give it an empty DmdEnv
                         `setIdArity` (exprArity work_rhs)
@@ -289,7 +291,7 @@ splitFun fn_id fn_info wrap_dmds res_info inline_act rhs
                                 -- arity is consistent with the demand type goes through
 
        wrap_rhs = wrap_fn work_id
-       wrap_id  = fn_id `setIdWorkerInfo` HasWorker work_id arity
+       wrap_id  = fn_id `setIdUnfolding` mkWwInlineRule work_id wrap_rhs arity
 
     ; return ([(work_id, work_rhs), (wrap_id, wrap_rhs)]) })
        -- Worker first, because wrapper mentions it