base + index register addressing

[Jeffrey A Law]

  In message < 199710171637.MAA26061@tweedledumb.cygnus.com >you write:
  > | It's worth noting that patch only helps when the base/index is a hard reg
  > ,
  > | which limits its usefulness on most of our platforms.  It's unclear if
  > | the benefit for handling scaled register would outweigh the work involved
  > .
  > 
  > Consider when the base register is the stack/frame/argument pointer.
Well, on targets where we do fp/ap elimination we still don't care
all that much since most don't have reg + scaled reg/const + constant offset.
Which is what such addresses will turn into when the fp/ap gets eliminated.

I'm not saying this extension isn't useful, just that it isn't as useful
as one might initially think.

jeff