oneShot (was Re: FoldrW/buildW issues)

[Joachim Breitner]

Hi,


Am Dienstag, den 07.10.2014, 03:05 -0400 schrieb David Feuer:
> Just for the heck of it, I tried out an implementation of scanl using
> Joachim Breitner's magical oneShot primitive. Using the test
>
> [..]
>
> with -O2 (NOT disabling Call Arity) the Core from barB is really,
> really beautiful: it's small, there are no lets or local lambdas, and
> everything is completely unboxed. This is much better than the result
> of barA, which has a local let, and which doesn't seem to manage to
> unbox anything.


I cannot reproduce this here. In fact, I get identical core in both
cases. Only when I do pass -fno-call-arity, A gets bad code, while B is
still good.

Maybe your example is too small?

Greetings,
Joachim

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

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