cvs commit: fptools/ghc/compiler/basicTypes Id.lhs IdInfo.lhs fptools/ghc/compiler/coreSyn Subst.lhs fptools/ghc/compiler/simplCore SetLevels.lhs SimplUtils.lhs Simplify.lhs fptools/ghc/compiler/specialise Specialise.lhs

[Simon Peyton Jones]

simonpj     2001/03/01 09:10:07 PST

  Modified files:
    ghc/compiler/basicTypes Id.lhs IdInfo.lhs 
    ghc/compiler/coreSyn Subst.lhs 
    ghc/compiler/simplCore SetLevels.lhs SimplUtils.lhs 
                           Simplify.lhs 
    ghc/compiler/specialise Specialise.lhs 
  Log:
  		Improve IdInfo substitution
  
  To get rules to work nicely, we need to make rules for recursive functions
  active in the RHS of the very recursive function itself.  This can be
  done nicely: the change is to move the calls to simplIdInfo in Simplify
  to an earlier place.
  
  The second thing is that when doing simple expression substitution
  in a rule (which we do during simplification for rules attached to an Id)
  we were zapping the occurrence info carefully pinned on the rule binders
  when the rule was put into the Id's rules.  This in turn meant that
  the simplifer ran more iterations than necessary when rules were fired.
  (Andrew Tolmach discovered this.)
  
  So I tidied up the interface to Subst a little.  The relevant functions
  that have changed are
  	simplBndr, simplBndrs, simplLetId, simplIdInfo,
  	substAndCloneId, substAndCloneIds, substAndCloneRecIds,
  
  There are consequential changes in other modules, but it compiles
  at least the whole standard libraries happily, and the codegen tests,
  so I'm reasonably confident in it.  But watch out for new strange
  happenings.
  
  Revision  Changes    Path
  1.83      +3 -5      fptools/ghc/compiler/basicTypes/Id.lhs
  1.68      +13 -54    fptools/ghc/compiler/basicTypes/IdInfo.lhs
  1.21      +190 -89   fptools/ghc/compiler/coreSyn/Subst.lhs
  1.44      +740 -743  fptools/ghc/compiler/simplCore/SetLevels.lhs
  1.60      +21 -14    fptools/ghc/compiler/simplCore/SimplUtils.lhs
  1.103     +41 -24    fptools/ghc/compiler/simplCore/Simplify.lhs
  1.73      +17 -18    fptools/ghc/compiler/specialise/Specialise.lhs