On 07/20/2016 06:09 PM, Jeff Law wrote:
So I'm going to let Richi run with the review on this one since the two
of you are already iterating. But I did have one comment on the
placement of the pass.
I believe one of the key things to consider for whether or not something
like this belongs in the cfgcleanup code is whether or not the
optimization is likely exposed repeatedly through the optimization
pipeline. If it's mostly a source level issue or only usually exposed
by a limited set of optimizers, then a separate pass might be better.
It can trigger before switchconv, and could expose optimization
opportunities there, but I've also seen it trigger much later. Since I
think it's cheap I don't see a reason not to put it in cfgcleanup, IMO
it's the best fit conceptually.
Bernd
