Implement INLINABLE pragma

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

diff --git a/compiler/stranal/WorkWrap.lhs b/compiler/stranal/WorkWrap.lhs
index 33ca298..d329b5a 100644 (file)
--- a/compiler/stranal/WorkWrap.lhs
+++ b/compiler/stranal/WorkWrap.lhs
@@ -7,23 +7,16 @@
 module WorkWrap ( wwTopBinds, mkWrapper ) where
 
 import CoreSyn
-import CoreUnfold      ( certainlyWillInline, mkInlineRule, mkWwInlineRule )
+import CoreUnfold      ( certainlyWillInline, mkInlineUnfolding, mkWwInlineRule )
 import CoreUtils       ( exprType, exprIsHNF )
 import CoreArity       ( exprArity )
 import Var
-import Id              ( idType, isOneShotLambda, idUnfolding,
-                         setIdStrictness, mkWorkerId, setInlinePragma,
-                         setInlineActivation, setIdUnfolding,
-                         setIdArity )
+import Id
 import Type            ( Type )
 import IdInfo
-import Demand           ( Demand(..), StrictSig(..), DmdType(..), DmdResult(..), 
-                         Demands(..), mkTopDmdType, isBotRes, returnsCPR, topSig, isAbsent
-                       )
+import Demand
 import UniqSupply
-import BasicTypes      ( RecFlag(..), isNonRec, isNeverActive,
-                          Activation(..), InlinePragma(..), 
-                         inlinePragmaActivation, inlinePragmaRuleMatchInfo )
+import BasicTypes
 import VarEnv          ( isEmptyVarEnv )
 import Maybes          ( orElse )
 import WwLib
@@ -229,6 +222,7 @@ tryWW is_rec fn_id rhs
   = return [ (fn_id, rhs) ]
 
   | is_thunk && worthSplittingThunk maybe_fn_dmd res_info
+       -- See Note [Thunk splitting]
   = ASSERT2( isNonRec is_rec, ppr new_fn_id )  -- The thunk must be non-recursive
     checkSize new_fn_id rhs $ 
     splitThunk new_fn_id rhs
@@ -277,8 +271,8 @@ checkSize fn_id rhs thing_inside
 
   | otherwise = thing_inside
   where
-    unfolding = idUnfolding fn_id
-    inline_rule = mkInlineRule unSaturatedOk rhs (unfoldingArity unfolding)
+    unfolding   = idUnfolding fn_id
+    inline_rule = mkInlineUnfolding Nothing rhs
 
 ---------------------
 splitFun :: Id -> IdInfo -> [Demand] -> DmdResult -> Expr Var
@@ -292,6 +286,12 @@ splitFun fn_id fn_info wrap_dmds res_info rhs
     ; let
        work_rhs = work_fn rhs
        work_id  = mkWorkerId work_uniq fn_id (exprType work_rhs) 
+                       `setIdOccInfo` occInfo fn_info
+                               -- Copy over occurrence info from parent
+                               -- Notably whether it's a loop breaker
+                               -- Doesn't matter much, since we will simplify next, but
+                               -- seems right-er to do so
+
                        `setInlineActivation` (inlinePragmaActivation inl_prag)
                                -- Any inline activation (which sets when inlining is active) 
                                -- on the original function is duplicated on the worker
@@ -310,16 +310,20 @@ splitFun fn_id fn_info wrap_dmds res_info rhs
                                 -- arity is consistent with the demand type goes through
 
        wrap_rhs  = wrap_fn work_id
-       wrap_prag = InlinePragma { inl_inline = True
+       wrap_prag = InlinePragma { inl_inline = Inline
+                                 , inl_sat    = Nothing
                                  , inl_act    = ActiveAfter 0
                                  , inl_rule   = rule_match_info }
+               -- See Note [Wrapper activation]
+               -- The RuleMatchInfo is (and must be) unaffected
+               -- The inl_inline is bound to be False, else we would not be
+               --    making a wrapper
 
        wrap_id   = fn_id `setIdUnfolding` mkWwInlineRule work_id wrap_rhs arity
                          `setInlinePragma` wrap_prag
-                               -- See Note [Wrapper activation]
-                               -- The RuleMatchInfo is (and must be) unaffected
-                               -- The inl_inline is bound to be False, else we would not be
-                               --    making a wrapper
+                         `setIdOccInfo` NoOccInfo
+                               -- Zap any loop-breaker-ness, to avoid bleating from Lint
+                               -- about a loop breaker with an INLINE rule
 
     ; return ([(work_id, work_rhs), (wrap_id, wrap_rhs)]) })
        -- Worker first, because wrapper mentions it
@@ -349,8 +353,8 @@ get_one_shots (Note _ e) = get_one_shots e
 get_one_shots _         = noOneShotInfo
 \end{code}
 
-Thunk splitting
-~~~~~~~~~~~~~~~
+Note [Thunk splitting]
+~~~~~~~~~~~~~~~~~~~~~~
 Suppose x is used strictly (never mind whether it has the CPR
 property).  
 
@@ -384,6 +388,7 @@ function, so that if x's demand is deeper (say U(U(L,L),L))
 then the splitting will go deeper too.
 
 \begin{code}
+-- See Note [Thunk splitting]
 -- splitThunk converts the *non-recursive* binding
 --     x = e
 -- into