X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2FcodeGen%2FSMRep.lhs;h=c807703b132a404273aaf450134c03cacbf9b51d;hb=28a464a75e14cece5db40f2765a29348273ff2d2;hp=1ffbcda56d9a9878a05dc7c68977ba65c6d503bd;hpb=d1c1b7d0e7b94ede238845c91f58582bad3b3ef3;p=ghc-hetmet.git

diff --git a/ghc/compiler/codeGen/SMRep.lhs b/ghc/compiler/codeGen/SMRep.lhs
index 1ffbcda..c807703 100644
--- a/ghc/compiler/codeGen/SMRep.lhs
+++ b/ghc/compiler/codeGen/SMRep.lhs
@@ -28,7 +28,7 @@ module SMRep (
 	SMRep(..), ClosureType(..),
 	isStaticRep,
 	fixedHdrSize, arrWordsHdrSize, arrPtrsHdrSize,
-	profHdrSize,
+	profHdrSize, thunkHdrSize,
 	tablesNextToCode,
 	smRepClosureType, smRepClosureTypeInt,
 
@@ -251,8 +251,8 @@ data SMRep
   = GenericRep		-- GC routines consult sizes in info tbl
 	Bool		-- True <=> This is a static closure.  Affects how 
 			-- 	    we garbage-collect it
-	!Int		-- # ptr words
-	!Int		-- # non-ptr words
+	!Int		--  # ptr words
+	!Int		--  # non-ptr words
 	ClosureType	-- closure type
 
   | BlackHoleRep
@@ -285,6 +285,12 @@ arrWordsHdrSize   = fixedHdrSize*wORD_SIZE + sIZEOF_StgArrWords_NoHdr
 
 arrPtrsHdrSize    :: ByteOff
 arrPtrsHdrSize    = fixedHdrSize*wORD_SIZE + sIZEOF_StgMutArrPtrs_NoHdr
+
+-- Thunks have an extra header word on SMP, so the update doesn't 
+-- splat the payload.
+thunkHdrSize :: WordOff
+thunkHdrSize = fixedHdrSize + smp_hdr
+	where smp_hdr = sIZEOF_StgSMPThunkHeader `quot` wORD_SIZE
 \end{code}
 
 \begin{code}