find, unsurprisingly, a Core expression.
\begin{code}
-{-# OPTIONS -w #-}
--- The above warning supression flag is a temporary kludge.
--- While working on this module you are encouraged to remove it and fix
--- any warnings in the module. See
--- http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings
--- for details
-
module CoreUnfold (
Unfolding, UnfoldingGuidance, -- Abstract types
couldBeSmallEnoughToInline,
certainlyWillInline, smallEnoughToInline,
- callSiteInline, CallContInfo(..)
+ callSiteInline, CallCtxt(..)
) where
import PrelNames
import Bag
import FastTypes
+import FastString
import Outputable
-import GHC.Exts ( Int# )
\end{code}
%************************************************************************
\begin{code}
+mkTopUnfolding :: CoreExpr -> Unfolding
mkTopUnfolding expr = mkUnfolding True {- Top level -} expr
+mkUnfolding :: Bool -> CoreExpr -> Unfolding
mkUnfolding top_lvl expr
= CoreUnfolding (occurAnalyseExpr expr)
top_lvl
= ptext SLIT("Unf") <+> sep [ppr top <+> ppr hnf <+> ppr cheap <+> ppr g,
ppr e]
+mkCompulsoryUnfolding :: CoreExpr -> Unfolding
mkCompulsoryUnfolding expr -- Used for things that absolutely must be unfolded
= CompulsoryUnfolding (occurAnalyseExpr expr)
\end{code}
-- We want to say "2 value binders". Why? So that
-- we take account of information given for the arguments
- go inline rev_vbs (Note InlineMe e) = go True rev_vbs e
+ go _ rev_vbs (Note InlineMe e) = go True rev_vbs e
go inline rev_vbs (Lam b e) | isId b = go inline (b:rev_vbs) e
| otherwise = go inline rev_vbs e
go inline rev_vbs e = (inline, reverse rev_vbs, e)
\end{code}
\begin{code}
-sizeExpr :: Int# -- Bomb out if it gets bigger than this
+sizeExpr :: FastInt -- Bomb out if it gets bigger than this
-> [Id] -- Arguments; we're interested in which of these
-- get case'd
-> CoreExpr
sizeExpr bOMB_OUT_SIZE top_args expr
= size_up expr
where
- size_up (Type t) = sizeZero -- Types cost nothing
- size_up (Var v) = sizeOne
+ size_up (Type _) = sizeZero -- Types cost nothing
+ size_up (Var _) = sizeOne
- size_up (Note InlineMe body) = sizeOne -- Inline notes make it look very small
+ size_up (Note InlineMe _) = sizeOne -- Inline notes make it look very small
-- This can be important. If you have an instance decl like this:
-- instance Foo a => Foo [a] where
-- {-# INLINE op1, op2 #-}
-- op2 = ...
-- then we'll get a dfun which is a pair of two INLINE lambdas
- size_up (Note _ body) = size_up body -- Other notes cost nothing
+ size_up (Note _ body) = size_up body -- Other notes cost nothing
- size_up (Cast e _) = size_up e
+ size_up (Cast e _) = size_up e
- size_up (App fun (Type t)) = size_up fun
+ size_up (App fun (Type _)) = size_up fun
size_up (App fun arg) = size_up_app fun [arg]
size_up (Lit lit) = sizeN (litSize lit)
case alts of
- [alt] -> size_up_alt alt `addSize` SizeIs 0# (unitBag (v, 1)) 0#
+ [alt] -> size_up_alt alt `addSize` SizeIs (_ILIT(0)) (unitBag (v, 1)) (_ILIT(0))
-- We want to make wrapper-style evaluation look cheap, so that
-- when we inline a wrapper it doesn't make call site (much) bigger
-- Otherwise we get nasty phase ordering stuff:
-- alts_size tries to compute a good discount for
-- the case when we are scrutinising an argument variable
- alts_size (SizeIs tot tot_disc tot_scrut) -- Size of all alternatives
- (SizeIs max max_disc max_scrut) -- Size of biggest alternative
- = SizeIs tot (unitBag (v, iBox (_ILIT 1 +# tot -# max)) `unionBags` max_disc) max_scrut
+ alts_size (SizeIs tot _tot_disc _tot_scrut) -- Size of all alternatives
+ (SizeIs max max_disc max_scrut) -- Size of biggest alternative
+ = SizeIs tot (unitBag (v, iBox (_ILIT(1) +# tot -# max)) `unionBags` max_disc) max_scrut
-- If the variable is known, we produce a discount that
-- will take us back to 'max', the size of rh largest alternative
-- The 1+ is a little discount for reduced allocation in the caller
= case globalIdDetails fun of
DataConWorkId dc -> conSizeN dc (valArgCount args)
- FCallId fc -> sizeN opt_UF_DearOp
+ FCallId _ -> sizeN opt_UF_DearOp
PrimOpId op -> primOpSize op (valArgCount args)
-- foldr addSize (primOpSize op) (map arg_discount args)
-- At one time I tried giving an arg-discount if a primop
-- if we know nothing about it. And just having it in a primop
-- doesn't help at all if we don't know something more.
- other -> fun_discount fun `addSizeN`
+ _ -> fun_discount fun `addSizeN`
(1 + length (filter (not . exprIsTrivial) args))
-- The 1+ is for the function itself
-- Add 1 for each non-trivial arg;
-- We should really only count for non-prim-typed args in the
-- general case, but that seems too much like hard work
- size_up_fun other args = size_up other
+ size_up_fun other _ = size_up other
------------
- size_up_alt (con, bndrs, rhs) = size_up rhs
+ size_up_alt (_con, _bndrs, rhs) = size_up rhs
-- Don't charge for args, so that wrappers look cheap
-- (See comments about wrappers with Case)
------------
-- We want to record if we're case'ing, or applying, an argument
- fun_discount v | v `elem` top_args = SizeIs 0# (unitBag (v, opt_UF_FunAppDiscount)) 0#
- fun_discount other = sizeZero
+ fun_discount v | v `elem` top_args = SizeIs (_ILIT(0)) (unitBag (v, opt_UF_FunAppDiscount)) (_ILIT(0))
+ fun_discount _ = sizeZero
------------
-- These addSize things have to be here because
-- tup = (a_1, ..., a_99)
-- x = case tup of ...
--
+mkSizeIs :: FastInt -> FastInt -> Bag (Id, Int) -> FastInt -> ExprSize
mkSizeIs max n xs d | (n -# d) ># max = TooBig
| otherwise = SizeIs n xs d
+maxSize :: ExprSize -> ExprSize -> ExprSize
maxSize TooBig _ = TooBig
maxSize _ TooBig = TooBig
maxSize s1@(SizeIs n1 _ _) s2@(SizeIs n2 _ _) | n1 ># n2 = s1
| otherwise = s2
-sizeZero = SizeIs (_ILIT 0) emptyBag (_ILIT 0)
-sizeOne = SizeIs (_ILIT 1) emptyBag (_ILIT 0)
-sizeN n = SizeIs (iUnbox n) emptyBag (_ILIT 0)
+sizeZero, sizeOne :: ExprSize
+sizeN :: Int -> ExprSize
+conSizeN :: DataCon ->Int -> ExprSize
+
+sizeZero = SizeIs (_ILIT(0)) emptyBag (_ILIT(0))
+sizeOne = SizeIs (_ILIT(1)) emptyBag (_ILIT(0))
+sizeN n = SizeIs (iUnbox n) emptyBag (_ILIT(0))
conSizeN dc n
- | isUnboxedTupleCon dc = SizeIs (_ILIT 0) emptyBag (iUnbox n +# _ILIT 1)
- | otherwise = SizeIs (_ILIT 1) emptyBag (iUnbox n +# _ILIT 1)
+ | isUnboxedTupleCon dc = SizeIs (_ILIT(0)) emptyBag (iUnbox n +# _ILIT(1))
+ | otherwise = SizeIs (_ILIT(1)) emptyBag (iUnbox n +# _ILIT(1))
-- Treat constructors as size 1; we are keen to expose them
-- (and we charge separately for their args). We can't treat
-- them as size zero, else we find that (iBox x) has size 1,
-- f x y z = case op# x y z of { s -> (# s, () #) }
-- and f wasn't getting inlined
+primOpSize :: PrimOp -> Int -> ExprSize
primOpSize op n_args
| not (primOpIsDupable op) = sizeN opt_UF_DearOp
| not (primOpOutOfLine op) = sizeN (2 - n_args)
-- and there's a good chance it'll get inlined back into C's RHS. Urgh!
| otherwise = sizeOne
-buildSize = SizeIs (-2#) emptyBag 4#
+buildSize :: ExprSize
+buildSize = SizeIs (_ILIT(-2)) emptyBag (_ILIT(4))
-- We really want to inline applications of build
-- build t (\cn -> e) should cost only the cost of e (because build will be inlined later)
-- Indeed, we should add a result_discount becuause build is
-- build is saturated (it usually is). The "-2" discounts for the \c n,
-- The "4" is rather arbitrary.
-augmentSize = SizeIs (-2#) emptyBag 4#
+augmentSize :: ExprSize
+augmentSize = SizeIs (_ILIT(-2)) emptyBag (_ILIT(4))
-- Ditto (augment t (\cn -> e) ys) should cost only the cost of
-- e plus ys. The -2 accounts for the \cn
-
-nukeScrutDiscount (SizeIs n vs d) = SizeIs n vs 0#
-nukeScrutDiscount TooBig = TooBig
+
+nukeScrutDiscount :: ExprSize -> ExprSize
+nukeScrutDiscount (SizeIs n vs _) = SizeIs n vs (_ILIT(0))
+nukeScrutDiscount TooBig = TooBig
-- When we return a lambda, give a discount if it's used (applied)
-lamScrutDiscount (SizeIs n vs d) = case opt_UF_FunAppDiscount of { d -> SizeIs n vs (iUnbox d) }
-lamScrutDiscount TooBig = TooBig
+lamScrutDiscount :: ExprSize -> ExprSize
+lamScrutDiscount (SizeIs n vs _) = case opt_UF_FunAppDiscount of { d -> SizeIs n vs (iUnbox d) }
+lamScrutDiscount TooBig = TooBig
\end{code}
\begin{code}
couldBeSmallEnoughToInline :: Int -> CoreExpr -> Bool
couldBeSmallEnoughToInline threshold rhs = case calcUnfoldingGuidance threshold rhs of
- UnfoldNever -> False
- other -> True
+ UnfoldNever -> False
+ _ -> True
certainlyWillInline :: Unfolding -> Bool
-- Sees if the unfolding is pretty certain to inline
certainlyWillInline (CoreUnfolding _ _ _ is_cheap (UnfoldIfGoodArgs n_vals _ size _))
= is_cheap && size - (n_vals +1) <= opt_UF_UseThreshold
-certainlyWillInline other
+certainlyWillInline _
= False
smallEnoughToInline :: Unfolding -> Bool
smallEnoughToInline (CoreUnfolding _ _ _ _ (UnfoldIfGoodArgs _ _ size _))
= size <= opt_UF_UseThreshold
-smallEnoughToInline other
+smallEnoughToInline _
= False
\end{code}
-> Id -- The Id
-> Bool -- True if there are are no arguments at all (incl type args)
-> [Bool] -- One for each value arg; True if it is interesting
- -> CallContInfo -- True <=> continuation is interesting
+ -> CallCtxt -- True <=> continuation is interesting
-> Maybe CoreExpr -- Unfolding, if any
-data CallContInfo = BoringCont
- | InterestingCont -- Somewhat interesting
- | CaseCont -- Very interesting; the argument of a case
- -- that decomposes its scrutinee
+data CallCtxt = BoringCtxt
+
+ | ArgCtxt Bool -- We're somewhere in the RHS of function with rules
+ -- => be keener to inline
+ Int -- We *are* the argument of a function with this arg discount
+ -- => be keener to inline
+ -- INVARIANT: ArgCtxt False 0 ==> BoringCtxt
+
+ | CaseCtxt -- We're the scrutinee of a case
+ -- that decomposes its scrutinee
-instance Outputable CallContInfo where
- ppr BoringCont = ptext SLIT("BoringCont")
- ppr InterestingCont = ptext SLIT("InterestingCont")
- ppr CaseCont = ptext SLIT("CaseCont")
+instance Outputable CallCtxt where
+ ppr BoringCtxt = ptext SLIT("BoringCtxt")
+ ppr (ArgCtxt _ _) = ptext SLIT("ArgCtxt")
+ ppr CaseCtxt = ptext SLIT("CaseCtxt")
callSiteInline dflags active_inline id lone_variable arg_infos cont_info
= case idUnfolding id of {
NoUnfolding -> Nothing ;
- OtherCon cs -> Nothing ;
+ OtherCon _ -> Nothing ;
CompulsoryUnfolding unf_template -> Just unf_template ;
-- CompulsoryUnfolding => there is no top-level binding
interesting_saturated_call
= case cont_info of
- BoringCont -> not is_top && n_vals_wanted > 0 -- Note [Nested functions]
- CaseCont -> not lone_variable || not is_value -- Note [Lone variables]
- InterestingCont -> n_vals_wanted > 0
+ BoringCtxt -> not is_top && n_vals_wanted > 0 -- Note [Nested functions]
+ CaseCtxt -> not lone_variable || not is_value -- Note [Lone variables]
+ ArgCtxt {} -> True
+ -- Was: n_vals_wanted > 0; but see test eyeball/inline1.hs
small_enough = (size - discount) <= opt_UF_UseThreshold
discount = computeDiscount n_vals_wanted arg_discounts
res_discount' arg_infos
res_discount' = case cont_info of
- BoringCont -> 0
- CaseCont -> res_discount
- InterestingCont -> 4 `min` res_discount
+ BoringCtxt -> 0
+ CaseCtxt -> res_discount
+ ArgCtxt _ _ -> 4 `min` res_discount
-- res_discount can be very large when a function returns
-- construtors; but we only want to invoke that large discount
-- when there's a case continuation.
projects / ghc-hetmet.git / blobdiff