X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2FcodeGen%2FCgPrimOp.hs;h=c99bdb4a740c084fb2b3ea0fc1b343047b54fa86;hb=12da626e907fd4b43272d7fa9a98ebc1a4bb0ebe;hp=7f100e283bc40ca183412402f6b5d4a30055f37a;hpb=a02e7f40afc1aab7fe466f949f505c1d7250713d;p=ghc-hetmet.git

diff --git a/compiler/codeGen/CgPrimOp.hs b/compiler/codeGen/CgPrimOp.hs
index 7f100e2..c99bdb4 100644
--- a/compiler/codeGen/CgPrimOp.hs
+++ b/compiler/codeGen/CgPrimOp.hs
@@ -571,9 +571,21 @@ doWriteByteArrayOp _ _ _ _
 
 doWritePtrArrayOp :: CmmExpr -> CmmExpr -> CmmExpr -> Code
 doWritePtrArrayOp addr idx val
-   = do stmtC (setInfo addr (CmmLit (CmmLabel mkMAP_DIRTY_infoLabel)))
-        mkBasicIndexedWrite arrPtrsHdrSize Nothing bWord addr idx val
-
+   = do mkBasicIndexedWrite arrPtrsHdrSize Nothing bWord addr idx val
+        stmtC (setInfo addr (CmmLit (CmmLabel mkMAP_DIRTY_infoLabel)))
+   -- the write barrier.  We must write a byte into the mark table:
+   -- bits8[a + header_size + StgMutArrPtrs_size(a) + x >> N]
+        stmtC $ CmmStore (
+          cmmOffsetExpr
+           (cmmOffsetExprW (cmmOffsetB addr arrPtrsHdrSize)
+                          (loadArrPtrsSize addr))
+           (CmmMachOp mo_wordUShr [idx,
+                                   CmmLit (mkIntCLit mUT_ARR_PTRS_CARD_BITS)])
+          ) (CmmLit (CmmInt 1 W8))
+
+loadArrPtrsSize :: CmmExpr -> CmmExpr
+loadArrPtrsSize addr = CmmLoad (cmmOffsetB addr off) bWord
+ where off = fixedHdrSize*wORD_SIZE + oFFSET_StgMutArrPtrs_ptrs
 
 mkBasicIndexedRead :: ByteOff -> Maybe MachOp -> CmmType 
 		   -> LocalReg -> CmmExpr -> CmmExpr -> Code