Call Arity, oneShot or both

Joachim Breitner mail at
Tue Oct 28 16:01:31 UTC 2014


Am Dienstag, den 28.10.2014, 15:45 +0100 schrieb Joachim Breitner:

> Also your suggestion to investigate fft2 was good: Turns out iterateFB
> would never inline, which defeats the purpose. With that fixed (just
> pushed to master) I expect Call Arity to handle the case in fft2 as
> well; well’ll see when the benchmarks finish.

indeed. So nofib gives no hard evidence that oneShot does any good (nor
does it do any harm).¹

But since it is plausible that there are cases out there where it might
help, even if just a little, we could go forward  –unless the
implementation becomes ugly. 

It also seems that the OS=Once flag survives most transformations just
fine; I had to add it to the list of IdInfo flags that make it through
TidyCore, though. Serializing and reading it from the interface was also
quite smooth.

I think I can prepare a differential revision soon. After writing some
Notes :-)


¹ We need more benchmarks.

Joachim “nomeata” Breitner
  mail at joachim-breitner.de
  Jabber: nomeata at  • GPG-Key: 0xF0FBF51F
  Debian Developer: nomeata at

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