base: Move PrimMVar to GHC.Internal.MVar

libraries/ghc-internal/src/GHC/Internal/Conc/Sync.hs

@@ -125,12 +125,9 @@ import GHC.Internal.MVar
 import GHC.Internal.Ptr
 import GHC.Internal.Real         ( fromIntegral )
 import GHC.Internal.Show         ( Show(..), showParen, showString )
-import GHC.Internal.Stable       ( StablePtr(..) )
 import GHC.Internal.Weak
 import GHC.Internal.Word
 
-import GHC.Internal.Unsafe.Coerce    ( unsafeCoerce# )
-
 infixr 0 `par`, `pseq`
 
 -----------------------------------------------------------------------------
@@ -671,20 +668,6 @@ mkWeakThreadId t@(ThreadId t#) = IO $ \s ->
       (# s1, w #) -> (# s1, Weak w #)
 
 
-data PrimMVar
-
--- | Make a 'StablePtr' that can be passed to the C function
--- @hs_try_putmvar()@.  The RTS wants a 'StablePtr' to the
--- underlying 'MVar#', but a 'StablePtr#' can only refer to
--- lifted types, so we have to cheat by coercing.
-newStablePtrPrimMVar :: MVar a -> IO (StablePtr PrimMVar)
-newStablePtrPrimMVar (MVar m) = IO $ \s0 ->
-  case makeStablePtr# (unsafeCoerce# m :: PrimMVar) s0 of
-    -- Coerce unlifted  m :: MVar# RealWorld a
-    --     to lifted    PrimMVar
-    -- apparently because mkStablePtr is not representation-polymorphic
-    (# s1, sp #) -> (# s1, StablePtr sp #)
-
 -----------------------------------------------------------------------------
 -- Transactional heap operations
 -----------------------------------------------------------------------------

libraries/ghc-internal/src/GHC/Internal/MVar.hs

@@ -30,9 +30,15 @@ module GHC.Internal.MVar (
         , tryReadMVar
         , isEmptyMVar
         , addMVarFinalizer
+
+          -- * PrimMVar
+        , PrimMVar
+        , newStablePtrPrimMVar
     ) where
 
 import GHC.Internal.Base
+import GHC.Internal.Stable       ( StablePtr(..) )
+import GHC.Internal.Unsafe.Coerce ( unsafeCoerce# )
 
 data MVar a = MVar (MVar# RealWorld a)
 {- ^
@@ -183,3 +189,17 @@ addMVarFinalizer :: MVar a -> IO () -> IO ()
 addMVarFinalizer (MVar m) (IO finalizer) =
     IO $ \s -> case mkWeak# m () finalizer s of { (# s1, _ #) -> (# s1, () #) }
 
+data PrimMVar
+
+-- | Make a 'StablePtr' that can be passed to the C function
+-- @hs_try_putmvar()@.  The RTS wants a 'StablePtr' to the
+-- underlying 'MVar#', but a 'StablePtr#' can only refer to
+-- lifted types, so we have to cheat by coercing.
+newStablePtrPrimMVar :: MVar a -> IO (StablePtr PrimMVar)
+newStablePtrPrimMVar (MVar m) = IO $ \s0 ->
+  case makeStablePtr# (unsafeCoerce# m :: PrimMVar) s0 of
+    -- Coerce unlifted  m :: MVar# RealWorld a
+    --     to lifted    PrimMVar
+    -- apparently because mkStablePtr is not representation-polymorphic
+    (# s1, sp #) -> (# s1, StablePtr sp #)
+