However, as usual for Gentle mode, do not inline things that are
inactive in the intial stages. See Note [Gentle mode].
+Note [InlineRule and preInlineUnconditionally]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Surprisingly, do not pre-inline-unconditionally Ids with INLINE pragmas!
+Example
+
+ {-# INLINE f #-}
+ f :: Eq a => a -> a
+ f x = ...
+
+ fInt :: Int -> Int
+ fInt = f Int dEqInt
+
+ ...fInt...fInt...fInt...
+
+Here f occurs just once, in the RHS of f1. But if we inline it there
+we'll lose the opportunity to inline at each of fInt's call sites.
+The INLINE pragma will only inline when the application is saturated
+for exactly this reason; and we don't want PreInlineUnconditionally
+to second-guess it. A live example is Trac #3736.
+ c.f. Note [InlineRule and postInlineUnconditionally]
+
Note [Top-level botomming Ids]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Don't inline top-level Ids that are bottoming, even if they are used just
preInlineUnconditionally :: SimplEnv -> TopLevelFlag -> InId -> InExpr -> Bool
preInlineUnconditionally env top_lvl bndr rhs
| not active = False
+ | isStableUnfolding (idUnfolding bndr) = False -- Note [InlineRule and preInlineUnconditionally]
| isTopLevel top_lvl && isBottomingId bndr = False -- Note [Top-level bottoming Ids]
| opt_SimplNoPreInlining = False
| otherwise = case idOccInfo bndr of
and now postInlineUnconditionally, losing the InlineRule on f. Now f'
won't inline because 'e' is too big.
+ c.f. Note [InlineRule and preInlineUnconditionally]
+
%************************************************************************
%* *
mkLam _b [] body
= return body
-mkLam env bndrs body
+mkLam _env bndrs body
= do { dflags <- getDOptsSmpl
; mkLam' dflags bndrs body }
where
; return etad_lam }
| dopt Opt_DoLambdaEtaExpansion dflags,
- not (inGentleMode env), -- In gentle mode don't eta-expansion
- -- because it can clutter up the code
- -- with casts etc that may not be removed
not (all isTyVar bndrs) -- Don't eta expand type abstractions
= do { let body' = tryEtaExpansion dflags body
; return (mkLams bndrs body') }