diff options
Diffstat (limited to 'compiler/GHC/Core/Opt/SetLevels.hs')
| -rw-r--r-- | compiler/GHC/Core/Opt/SetLevels.hs | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/compiler/GHC/Core/Opt/SetLevels.hs b/compiler/GHC/Core/Opt/SetLevels.hs index 9e2376da45..a8a99ba42f 100644 --- a/compiler/GHC/Core/Opt/SetLevels.hs +++ b/compiler/GHC/Core/Opt/SetLevels.hs @@ -85,7 +85,7 @@ import GHC.Core.Utils ( exprType, exprIsHNF , collectMakeStaticArgs , mkLamTypes ) -import GHC.Core.Opt.Arity ( exprBotStrictness_maybe ) +import GHC.Core.Opt.Arity ( exprBotStrictness_maybe, isOneShotBndr ) import GHC.Core.FVs -- all of it import GHC.Core.Subst import GHC.Core.Make ( sortQuantVars ) @@ -1384,9 +1384,11 @@ lvlLamBndrs env lvl bndrs new_lvl | any is_major bndrs = incMajorLvl lvl | otherwise = incMinorLvl lvl - is_major bndr = isId bndr && not (isProbablyOneShotLambda bndr) - -- The "probably" part says "don't float things out of a - -- probable one-shot lambda" + is_major bndr = not (isOneShotBndr bndr) + -- Only non-one-shot lambdas bump a major level, which in + -- turn triggers floating. NB: isOneShotBndr is always + -- true of a type variable -- there is no point in floating + -- out of a big lambda. -- See Note [Computing one-shot info] in GHC.Types.Demand lvlJoinBndrs :: LevelEnv -> Level -> RecFlag -> [OutVar] |