summaryrefslogtreecommitdiff
path: root/compiler/GHC/Core/Opt/SetLevels.hs
diff options
context:
space:
mode:
Diffstat (limited to 'compiler/GHC/Core/Opt/SetLevels.hs')
-rw-r--r--compiler/GHC/Core/Opt/SetLevels.hs10
1 files changed, 9 insertions, 1 deletions
diff --git a/compiler/GHC/Core/Opt/SetLevels.hs b/compiler/GHC/Core/Opt/SetLevels.hs
index 0a1395a432..cef8230436 100644
--- a/compiler/GHC/Core/Opt/SetLevels.hs
+++ b/compiler/GHC/Core/Opt/SetLevels.hs
@@ -91,11 +91,13 @@ import GHC.Types.Demand ( StrictSig, Demand, isStrictDmd, splitStrictSig,
import GHC.Types.Cpr ( mkCprSig, botCpr )
import GHC.Types.Name ( getOccName, mkSystemVarName )
import GHC.Types.Name.Occurrence ( occNameString )
+import GHC.Types.Unique ( hasKey )
import GHC.Core.Type ( Type, mkLamTypes, splitTyConApp_maybe, tyCoVarsOfType
, mightBeUnliftedType, closeOverKindsDSet )
import GHC.Types.Basic ( Arity, RecFlag(..), isRec )
import GHC.Core.DataCon ( dataConOrigResTy )
import GHC.Builtin.Types
+import GHC.Builtin.Names ( runRWKey )
import GHC.Types.Unique.Supply
import GHC.Utils.Misc
import GHC.Utils.Outputable
@@ -399,8 +401,14 @@ lvlNonTailExpr env expr
lvlApp :: LevelEnv
-> CoreExprWithFVs
-> (CoreExprWithFVs, [CoreExprWithFVs]) -- Input application
- -> LvlM LevelledExpr -- Result expression
+ -> LvlM LevelledExpr -- Result expression
lvlApp env orig_expr ((_,AnnVar fn), args)
+ -- Try to ensure that runRW#'s continuation isn't floated out.
+ -- See Note [Simplification of runRW#].
+ | fn `hasKey` runRWKey
+ = do { args' <- mapM (lvlExpr env) args
+ ; return (foldl' App (lookupVar env fn) args') }
+
| floatOverSat env -- See Note [Floating over-saturated applications]
, arity > 0
, arity < n_val_args