unfinished/compiler/machine.bluesky/simplifier/simplifier.factor

   1 ! Copyright (C) 2008 Slava Pestov.
   2 ! See http://factorcode.org/license.txt for BSD license.
   3 USING: kernel accessors namespaces sequences.next compiler.lvops ;
   4 IN: compiler.machine.simplifier
   5
   6 : useless-branch? ( next insn -- ? )
   7     2dup [ _label? ] [ _b? ] bi* and
   8     [ [ label>> ] bi@ = ] [ 2drop f ] if ;
   9
  10 : simplify-mr ( insns -- insns )
  11     #! Remove unconditional branches to labels immediately
  12     #! following.
  13     [
  14         [
  15             tuck useless-branch?
  16             [ drop ] [ , ] if
  17         ] each-next
  18     ] { } make ;