1 files changed, 5 insertions, 55 deletions
diff --git a/compiler/GHC/Prelude.hs b/compiler/GHC/Prelude.hs
index 81d860f618..30f67573cf 100644
--- a/compiler/GHC/Prelude.hs
+++ b/compiler/GHC/Prelude.hs
@@ -13,10 +13,8 @@
 --   * Explicitly imports GHC.Prelude
 
 module GHC.Prelude
-  (module X
-  ,Applicative (..)
-  ,module Bits
-  ,shiftL, shiftR
+  (module GHC.Prelude
+  ,module GHC.Utils.Trace
   ) where
 
 
@@ -48,55 +46,7 @@ NoImplicitPrelude. There are two motivations for this:
     extensions.
 -}
 
-import Prelude as X hiding ((<>), Applicative(..))
-import Control.Applicative (Applicative(..))
-import Data.Foldable as X (foldl')
+import GHC.Prelude.Basic as GHC.Prelude
 
-#if MIN_VERSION_base(4,16,0)
-import GHC.Bits as Bits hiding (shiftL, shiftR)
-# if defined(DEBUG)
-import qualified GHC.Bits as Bits (shiftL, shiftR)
-# endif
-
-#else
---base <4.15
-import Data.Bits as Bits hiding (shiftL, shiftR)
-# if defined(DEBUG)
-import qualified Data.Bits as Bits (shiftL, shiftR)
-# endif
-#endif
-
-{- Note [Default to unsafe shifts inside GHC]
-   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-The safe shifts can introduce branches which come
-at the cost of performance. We still want the additional
-debugability for debug builds. So we define it as one or the
-other depending on the DEBUG setting.
-
-Why do we then continue on to re-export the rest of Data.Bits?
-If we would not what is likely to happen is:
-* Someone imports Data.Bits, uses xor. Things are fine.
-* They add a shift and get an ambiguous definition error.
-* The are puzzled for a bit.
-* They either:
-  + Remove the import of Data.Bits and get an error because xor is not in scope.
-  + Add the hiding clause to the Data.Bits import for the shifts.
-
-Either is quite annoying. Simply re-exporting all of Data.Bits avoids this
-making for a smoother developer experience. At the cost of having a few more
-names in scope at all time. But that seems like a fair tradeoff.
-
-See also #19618
--}
-
--- We always want the Data.Bits method to show up for rules etc.
-{-# INLINE shiftL #-}
-{-# INLINE shiftR #-}
-shiftL, shiftR :: Bits.Bits a => a -> Int -> a
-#if defined(DEBUG)
-shiftL = Bits.shiftL
-shiftR = Bits.shiftR
-#else
-shiftL = Bits.unsafeShiftL
-shiftR = Bits.unsafeShiftR
-#endif
+-- import {-# SOURCE #-} GHC.Utils.Trace
+import GHC.Utils.Trace hiding ( trace )