Platform dependent flag adjustments

[Christian Thalinger]

On Oct 17, 2012, at 10:18 AM, Volker Simonis <volker.simonis at gmail.com> wrote:

> Hi,
> 
> for our PowerPC/AIX port I'm currently looking for a place where I can
> do platform dependent adjustments to command line arguments which are
> available on special platforms only.
> 
> For our private ports, we did all these adjustments conditionally in
> 'parse_each_vm_init_arg()' and I noticed that the original version of
> this method already contains platforms specific parts (e.g.
> SOLARIS_ONLY(..)). But these solution is not very attractive because
> it clutters shared code. It also seems unintuitive to handle platform
> dependent flags which are declared in special platform dependent files
> (e.g. src/cpu/<arch>/vm/globals_<arch>.hpp:) in a central shared
> method. Finally the current solution will scale poorly with new
> platform ports coming into the OpenJDK.
> 
> I also noticed that the the 'Arguments' class declares a static method
> 'do_pd_flag_adjustments()'. Unfortunately this method is never defined
> nor called. I saw that this method was there from the initial checkin
> and I'm wondering if this was a first attempt to generalize  the  flag
> adjustment?

Indeed:

$ ack -a do_pd_flag_adjustments src/
src/share/vm/runtime/arguments.hpp
335:  static void do_pd_flag_adjustments();

Maybe we should bring it to life?  Or at least remove the declaration if not.

-- Chris

> 
> Or perhaps there's an even better way to do platform dependent flag
> adjustments which I've just missed?
> 
> Any insights and hints are highly welcome.
> 
> Regards,
> Volker