[commit: ghc] master: Remove -ddump-simpl-phases flag (ad8457f)

[Jan Stolarek]

Simon Marlow wrote:
> isn't -ddump-simpl-phases useful?  what's the other way to do that?
-dverbose-core2core + -ddump-simple-stats

Johan Tibell wrote:
> I think this flag is useful for debugging e.g. why something didn't
> optimize the way you thought.
Well, you can get that information using flags mentioned above. It seemed that -ddump-simpl-phases 
is not used and can be safely removed. It wasn't documented at all, so the only way to figure out 
how it works was to look hard at the code. The output itself was rather cryptic - no information 
about the phase for which the stats are displayed. Again, the only way to make sense of that 
output was looking at the code to figure out the precise ordering of Core optimisations. 
With -dverbose-core2core the output makes a lot more sense because it directly follows the output 
of the phase.

Simon PJ and Austin spoke in favour of removing that flag, so I went ahead and did that. But if 
indeed was used by someone to do their work we could revert that.

Janek