On Saturday 17 October 2009, Edgar E. Iglesias wrote: > I looked at the s390 patches and was also unsure about this sync op. > I'm not convinced it's bad but my first feeling was as Aurelien points > out that the translator shoud take care of it.
Indeed. I would have expected it to, in fact. But it doesn't. The sync op is the simplest and quickest way to get what I want that I could come up with. I'd be perfectly happy if TCG could handle aliases on its own, but doing a lot of ALU operations on every register access is not an option. > Another thing I noticed was the large amount of helpers. Without > looking at the details my feeling was that you could probably do more > at translation time. My experience is that helper functions have an undeservedly bad image. A pure const helper call is very easy to optimize away for TCG. Random bit shifting, comparing and branching isn't. > Nice work! Thank you. CU Uli -- SUSE LINUX Products GmbH, GF: Markus Rex, HRB 16746 (AG Nürnberg)
