alias update

[Jeffrey A Law]

  In message < 199712240350.WAA09681@jfc. >you write:
  > 
  > These changes eliminate the variable flag_alias_check: the new alias
  > checking code is now always enabled.  The old global address alias
  > code from memrefs_conflict_p is removed.  There are some minor code
  > generation improvements from calling canon_rtx before base_alias_check
  > in *_dependence() and recognizing the C++ global new operator as a
  > malloc-like function.
  > 
  > Most of the init_alias_analysis diff is indentation changes.
[ ... ]
Thanks.  Installed.

jeff