3 files changed, 0 insertions, 27 deletions
diff --git a/compiler/cmm/CmmMachOp.hs b/compiler/cmm/CmmMachOp.hs
index d8ce492de1..c4ec393ad6 100644
--- a/compiler/cmm/CmmMachOp.hs
+++ b/compiler/cmm/CmmMachOp.hs
@@ -19,9 +19,6 @@ module CmmMachOp
     -- CallishMachOp
     , CallishMachOp(..), callishMachOpHints
     , pprCallishMachOp
-
-    -- Atomic read-modify-write
-    , AtomicMachOp(..)
    )
 where
 
@@ -550,24 +547,8 @@ data CallishMachOp
 
   | MO_PopCnt Width
   | MO_BSwap Width
-
-  -- Atomic read-modify-write.
-  | MO_AtomicRMW Width AtomicMachOp
-  | MO_AtomicRead Width
-  | MO_AtomicWrite Width
-  | MO_Cmpxchg Width
   deriving (Eq, Show)
 
--- | The operation to perform atomically.
-data AtomicMachOp =
-      AMO_Add
-    | AMO_Sub
-    | AMO_And
-    | AMO_Nand
-    | AMO_Or
-    | AMO_Xor
-      deriving (Eq, Show)
-
 pprCallishMachOp :: CallishMachOp -> SDoc
 pprCallishMachOp mo = text (show mo)
 
diff --git a/compiler/cmm/CmmSink.hs b/compiler/cmm/CmmSink.hs
index 4dced9afd2..4c025425ab 100644
--- a/compiler/cmm/CmmSink.hs
+++ b/compiler/cmm/CmmSink.hs
@@ -650,10 +650,6 @@ data AbsMem
 -- perhaps we ought to have a special annotation for calls that can
 -- modify heap/stack memory.  For now we just use the conservative
 -- definition here.
---
--- Some CallishMachOp imply a memory barrier e.g. AtomicRMW and
--- therefore we should never float any memory operations across one of
--- these calls.
 
 
 bothMems :: AbsMem -> AbsMem -> AbsMem
diff --git a/compiler/cmm/PprC.hs b/compiler/cmm/PprC.hs
index 455c79ba02..47b247e278 100644
--- a/compiler/cmm/PprC.hs
+++ b/compiler/cmm/PprC.hs
@@ -753,10 +753,6 @@ pprCallishMachOp_for_C mop
         MO_Memmove      -> ptext (sLit "memmove")
         (MO_BSwap w)    -> ptext (sLit $ bSwapLabel w)
         (MO_PopCnt w)   -> ptext (sLit $ popCntLabel w)
-        (MO_AtomicRMW w amop) -> ptext (sLit $ atomicRMWLabel w amop)
-        (MO_Cmpxchg w)  -> ptext (sLit $ cmpxchgLabel w)
-        (MO_AtomicRead w)  -> ptext (sLit $ atomicReadLabel w)
-        (MO_AtomicWrite w) -> ptext (sLit $ atomicWriteLabel w)
         (MO_UF_Conv w)  -> ptext (sLit $ word2FloatLabel w)
 
         MO_S_QuotRem  {} -> unsupported