By: Exophase (exophase.delete@this.gmail.com), May 7, 2013 9:05 am
Room: Moderated Discussions
Exophase (exophase.delete@this.gmail.com) on May 7, 2013 9:00 am wrote:
> Unless there are unknown restrictions and it's confirmed that the two parts can't be scheduled
> independently I don't see why you'd want to avoid it.
Sorry, I somehow missed Wilco's mention of "single use" here, the comment makes much more sense. But even for double use it might still be preferable in some cases, since that would be two vs three instructions (decode/retire/rename/ROB/etc slots), even though it'd be four vs three execution ports tied up. With only one memory port that could become a bottleneck pretty easily, although that'd often be the case w/Saltwell too.
I wonder if there's any detail available about how many times a load is referenced in typical compiled code..
> Unless there are unknown restrictions and it's confirmed that the two parts can't be scheduled
> independently I don't see why you'd want to avoid it.
Sorry, I somehow missed Wilco's mention of "single use" here, the comment makes much more sense. But even for double use it might still be preferable in some cases, since that would be two vs three instructions (decode/retire/rename/ROB/etc slots), even though it'd be four vs three execution ports tied up. With only one memory port that could become a bottleneck pretty easily, although that'd often be the case w/Saltwell too.
I wonder if there's any detail available about how many times a load is referenced in typical compiled code..