[PATCH v2] Single threaded stdio optimization

[Siddhesh Poyarekar]

On Thursday 29 June 2017 06:59 PM, Szabolcs Nagy wrote:
> this does not do what we want:
> single check + tailcall the unlocked version.
> 
> with your code gcc is more likely to do two
> checks and register spills and an additional
> return.
> 
> while my code does not force gcc to do the
> right thing at least it shows the intent.

Can you verify this both ways?  If they don't show any noticeable
difference then I prefer the way I suggested, but that is really just
for aesthetics.  Maybe also provide a __glibc_unlikely hint to aid the
compiler.

Siddhesh