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Re: Single-item padrange?

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From:
Father Chrysostomos
Date:
October 18, 2014 00:52
Subject:
Re: Single-item padrange?
Message ID:
20141018005238.29921.qmail@lists-nntp.develooper.com
Dave Mitchell wrote:
> In short, padrange executes more
> instructions, but has less data reads and writes; the overall effect on
> the combined cache being marginally worse. So perhaps I should change it
> for only two+ pad vars (or 1 pad var plus @_)?

I have done that in commit a3353dbeb

I also noticed a case in which padrange happened in 5.18, but was dis-
abled in 5.20 due to the list+pushmark optimisation:

() = (0,my($b,$c))

With padrange it's:    padrange, list
Without padrange it's: padsv, padsv

Could you try running this through cachegrind, both with and without
the list+pushmark optimisation, and perhaps with different numbers
of lexicals?

I disabled the list+pushmark optimisation on the
sprout/nolistpushmarkopt branch to facilitate this.


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