No documentation of -fsched-pressure-algorithm

[nick clifton]

Hi Richard,

> Well, given the replies from you, Ian and Vlad (when reviewing the patch),
> I feel once again in a minority of one here :-) but... I just don't
> think we should be advertising this sort of stuff to users.

OK, what about Ian's suggestion of controlling the algorithm selection 
via a --param instead of a -f option ?


> Not because
> I'm trying to be cliquey, but because any time the user ends up having
> to use stuff like this represents a failure on the part of the compiler.

A nice idea in principle, but in practice GCC already has a ton of these 
specialist options.  Maybe you feel that we should not be adding another 
one to this list, but I think that we are already too far gone.  GCC and 
its long list of command line options is an established norm.

Perhaps now is the time to consider embracing projects like Acovea and 
Milepost and making them an official, easier-to-use meta front end to gcc ?


> I mean, at what level would we document it?

Well I rather like David's suggestion - a split gcc invocation manual 
with options like -fsched-pressure-algorithm only appearing in the 
here-be-dragons section.


>   "Here, we happen to have two algorithms to do this.
>    Treat them as black boxes, try each one on each
 >    source file, and see what works out best."

Or:

     "Here, we have two algorithms to do this. You can
      treat them as black boxes, try both and see which
      works best for your application.  Or you can delve
      into their intricacies to see which ought to be the
      better one for your target. See this post <link to
      your submission> for a description of the algorithms.
      Either way we would be interested in hearing about
      which algorithm works best for you, what your application
      looks like and which architecture you are using.
      Please contact us at ...."


Cheers
   Nick