Re: -fwhopr and -flto options reorg

[Jan Hubicka <hubicka at ucw dot cz>]

> 
> Yes I was confused both by the option name and documentation for -fwpa:
> 
> "This option runs the link-time optimizer in the
> whole-program-analysis (WPA) mode, which reads in summary information
> from all inputs and performs a whole-program analysis based on summary
> information only..."

Indeed, this is very confusing.  I wich WHOPR didn't have "whope program" bulilt in.
Since this is option accepted by lto1 only and intended to be produced only by driver,
do we need user documentation here at all?

Otherwise, I would probably re-word the documentation to not expand the acronym and keep
it only "This option is accepted only by lto frontend. It runs serial inter-procedural
propagation stage of link time optimization"

same for ltrans, ltrans-list and other. Those are all internal options.

I will try to re-read lto docs and see what can be clarified.

Honza
> 
> >
> > -fwhole-program makes whole program assumptions and so does -fuse-linker-plugin
> > where supported. I plan to make -fuse-linker-plugin default as incremental change.
> >
> 
> This is more sane ..
> 
> Thanks,
> 
> David
> 
> > Users needs to know about both lto and whole-program, unfortunately.
> > LLVM for example defaults to -fwhole-program when it finds main() function.
> >
> >> are still some limited full program analysis that can be done with
> >> linker feedback -- such as global variable address exposure analysis
> >> -- also applies to shared library build for hidden symbols etc.
> >>
> >> If partition=none means all files are LTOed together in memory, I fail
> >> to understand why it implies wpa=off.
> >>
> >> Another question, what is the default for parallelism? jobserv/auto?
> >> or 1? For auto, is it the number of cores available?
> >
> > 1 for the moment. ?I plan to switch it to jobserv when environemnt var is found.
> > Autodetecting number of cores when jobserv is not around seems sane too. We can
> > call it auto.
> >
> > Honza
> >>
> >> Thanks,
> >>
> >> David
> >>
> >>
> >> >
> >> > Honza
> >> >>
> >> >> Thanks,
> >> >>
> >> >> David
> >> >>
> >> >> >
> >> >> > Honza
> >> >> >
> >> >
> >