diff options
Diffstat (limited to 'compiler/codeGen')
| -rw-r--r-- | compiler/codeGen/StgCmmPrim.hs | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/compiler/codeGen/StgCmmPrim.hs b/compiler/codeGen/StgCmmPrim.hs index d3c09c584e..2169465fbb 100644 --- a/compiler/codeGen/StgCmmPrim.hs +++ b/compiler/codeGen/StgCmmPrim.hs @@ -308,8 +308,11 @@ emitPrimOp _ [res] GetCurrentCCSOp [_dummy_arg] emitPrimOp dflags [res] ReadMutVarOp [mutv] = emitAssign (CmmLocal res) (cmmLoadIndexW dflags mutv (fixedHdrSizeW dflags) (gcWord dflags)) -emitPrimOp dflags [] WriteMutVarOp [mutv,var] - = do emitStore (cmmOffsetW dflags mutv (fixedHdrSizeW dflags)) var +emitPrimOp dflags res@[] WriteMutVarOp [mutv,var] + = do -- Without this write barrier, other CPUs may see this pointer before + -- the writes for the closure it points to have occurred. + emitPrimCall res MO_WriteBarrier [] + emitStore (cmmOffsetW dflags mutv (fixedHdrSizeW dflags)) var emitCCall [{-no results-}] (CmmLit (CmmLabel mkDirty_MUT_VAR_Label)) |