diff options
Diffstat (limited to 'compiler/GHC/Types/Demand.hs')
| -rw-r--r-- | compiler/GHC/Types/Demand.hs | 28 |
1 files changed, 8 insertions, 20 deletions
diff --git a/compiler/GHC/Types/Demand.hs b/compiler/GHC/Types/Demand.hs index ed7ef25aa8..b4f6f3e549 100644 --- a/compiler/GHC/Types/Demand.hs +++ b/compiler/GHC/Types/Demand.hs @@ -98,7 +98,6 @@ import GHC.Utils.Binary import GHC.Utils.Misc import GHC.Utils.Outputable import GHC.Utils.Panic -import GHC.Utils.Panic.Plain import Data.Function @@ -880,20 +879,7 @@ isUsedOnceDmd (n :* _) = isUsedOnce n -- signatures for analysis performance reasons. -- See Note [Lazy and unleashable free variables] in "GHC.Core.Opt.DmdAnal". isWeakDmd :: Demand -> Bool -isWeakDmd dmd@(n :* _) = not (isStrict n) && is_plus_idem_dmd dmd - where - -- @is_plus_idem_* thing@ checks whether @thing `plus` thing = thing@, - -- e.g. if @thing@ is idempotent wrt. to @plus@. - -- is_plus_idem_card n = plusCard n n == n - is_plus_idem_card = isCardNonOnce - -- is_plus_idem_dmd dmd = plusDmd dmd dmd == dmd - is_plus_idem_dmd AbsDmd = True - is_plus_idem_dmd BotDmd = True - is_plus_idem_dmd (n :* sd) = is_plus_idem_card n && is_plus_idem_sub_dmd sd - -- is_plus_idem_sub_dmd sd = plusSubDmd sd sd == sd - is_plus_idem_sub_dmd (Poly _ n) = assert (isCardNonOnce n) True - is_plus_idem_sub_dmd (Prod _ ds) = all is_plus_idem_dmd ds - is_plus_idem_sub_dmd (Call n _) = is_plus_idem_card n -- See Note [Call demands are relative] +isWeakDmd _ = False evalDmd :: Demand evalDmd = C_1N :* topSubDmd @@ -1503,11 +1489,13 @@ data DmdType instance Eq DmdType where (==) (DmdType fv1 ds1 div1) - (DmdType fv2 ds2 div2) = nonDetUFMToList fv1 == nonDetUFMToList fv2 - -- It's OK to use nonDetUFMToList here because we're testing for - -- equality and even though the lists will be in some arbitrary - -- Unique order, it is the same order for both - && ds1 == ds2 && div1 == div2 + (DmdType fv2 ds2 div2) = div1 == div2 && ds1 == ds2 -- cheap checks first + && as_list div1 fv1 == as_list div2 fv2 + where + as_list div = filter (\(_, dmd) -> dmd /= defaultFvDmd div) . nonDetUFMToList + -- It's OK to use nonDetUFMToList here because we're testing for + -- equality and even though the lists will be in some arbitrary + -- Unique order, it is the same order for both -- | Compute the least upper bound of two 'DmdType's elicited /by the same -- incoming demand/! |