Repository : ssh://darcs.haskell.org//srv/darcs/ghc On branch : master
http://hackage.haskell.org/trac/ghc/changeset/1435eef2422d3f9120b9bafb3fa497b0c505055d >--------------------------------------------------------------- commit 1435eef2422d3f9120b9bafb3fa497b0c505055d Author: Johan Tibell <johan.tib...@gmail.com> Date: Fri Dec 7 14:08:21 2012 -0800 Refactor primitive field unpacking check >--------------------------------------------------------------- compiler/typecheck/TcTyClsDecls.lhs | 47 ++++++++++++++++++---------------- 1 files changed, 25 insertions(+), 22 deletions(-) diff --git a/compiler/typecheck/TcTyClsDecls.lhs b/compiler/typecheck/TcTyClsDecls.lhs index a760601..f49a663 100644 --- a/compiler/typecheck/TcTyClsDecls.lhs +++ b/compiler/typecheck/TcTyClsDecls.lhs @@ -37,7 +37,6 @@ import TcClassDcl import TcHsType import TcMType import TcType -import qualified TysPrim import TysWiredIn( unitTy ) import Type import Kind @@ -1251,8 +1250,8 @@ chooseBoxingStrategy dflags arg_ty bang Just (arg_tycon, _) | isAbstractTyCon arg_tycon -> False -- See Note [Don't complain about UNPACK on abstract TyCons] - | isPrimTyCon arg_tycon && - arg_tycon `elem` ptrSizedPrimTyCons -> True + | isPrimTyCon arg_tycon && hasPtrSizedRep (tyConPrimRep arg_tycon) + -> True -- TODO: Check that the PrimTyCon corresponds to a type -- with pointer-sized representation. | isEmptyDataTyCon arg_tycon -> True @@ -1261,25 +1260,22 @@ chooseBoxingStrategy dflags arg_ty bang -> can_unbox_prim ty | otherwise -> False -ptrSizedPrimTyCons :: [TyCon] -ptrSizedPrimTyCons = - [ TysPrim.addrPrimTyCon - , TysPrim.arrayPrimTyCon - , TysPrim.byteArrayPrimTyCon - , TysPrim.arrayArrayPrimTyCon - , TysPrim.charPrimTyCon - , TysPrim.doublePrimTyCon - , TysPrim.floatPrimTyCon - , TysPrim.intPrimTyCon - , TysPrim.int32PrimTyCon - , TysPrim.int64PrimTyCon - , TysPrim.mutableArrayPrimTyCon - , TysPrim.mutableByteArrayPrimTyCon - , TysPrim.mutableArrayArrayPrimTyCon - , TysPrim.wordPrimTyCon - , TysPrim.word32PrimTyCon - , TysPrim.word64PrimTyCon - ] + +-- | Return True if representation can be considered pointer-sized (or +-- smaller) in the context of unpacking. +hasPtrSizedRep :: PrimRep -> Bool +-- We explicitly enumerate the PrimReps so that if another PrimRep is +-- ever added we'll get a pattern match warning which will make sure +-- we consider the new case here: +hasPtrSizedRep IntRep = True +hasPtrSizedRep WordRep = True +hasPtrSizedRep Int64Rep = True -- See Note [Primitive size exception] +hasPtrSizedRep Word64Rep= True -- See Note [Primitive size exception] +hasPtrSizedRep FloatRep = True -- NB. might not take a full word +hasPtrSizedRep DoubleRep= True -- See Note [Primitive size exception] +hasPtrSizedRep AddrRep = True +hasPtrSizedRep PtrRep = True +hasPtrSizedRep VoidRep = True \end{code} @@ -1307,6 +1303,13 @@ But it's the *argument* type that matters. This is fine: data S = MkS S !Int because Int is non-recursive. +Note [Primitive size exception] +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +For consistency reasons we make an exception to the size requirement +for Doubles, Word64s, and Int64s on 32-bit architectures. Not doing so +might have surprising performance implications if code is moved from a +64-bit to a 32-bit architecture. + %************************************************************************ %* * _______________________________________________ Cvs-ghc mailing list Cvs-ghc@haskell.org http://www.haskell.org/mailman/listinfo/cvs-ghc
