Hello Andrew, Tuesday, May 20, 2008, 11:05:52 PM, you wrote:
-funbox-strict-fields.
I did try that, but it didn't seem to make any difference for me. [Maybe
it may be that ghc just not recompiled program when you supplied this switch. as i wrote, this switch by itself made your original program 1.5x faster on my box. try to delete .o/.exe before rebuilding and, without this switch representation for !Int32 is the same as for Int32 - only difference is that when data is assigned to such field they are evaluated first (and then boxed) it is not enabled by default, because for *non-primitive* datatypes such as B below automatic unboxing of strict fields of this type may decrease sharing and thus memory/performance. imagine for example: data A = A !B !B data B = B !Int !Int !Int !Int !Int b = B 1 1 1 1 1 a = A b b jhc automatically unboxes strict fields of primitive datatypes, which is guaranteed to provide only positive effects. may be somesay the same will be added to ghc -- Best regards, Bulat mailto:Bulat.Ziganshin@gmail.com