basis/compiler/cfg/critical-edges/critical-edges.factor

   1 ! Copyright (C) 2009 Slava Pestov.
   2 ! See http://factorcode.org/license.txt for BSD license.
   3 USING: kernel math accessors sequences
   4 compiler.cfg compiler.cfg.rpo compiler.cfg.utilities ;
   5 IN: compiler.cfg.critical-edges
   6
   7 : critical-edge? ( from to -- ? )
   8     [ successors>> length 1 > ] [ predecessors>> length 1 > ] bi* and ;
   9
  10 : split-critical-edge ( from to -- )
  11     f <simple-block> insert-basic-block ;
  12
  13 : split-critical-edges ( cfg -- )
  14     dup [
  15         dup successors>> [
  16             2dup critical-edge?
  17             [ split-critical-edge ] [ 2drop ] if
  18         ] with each
  19     ] each-basic-block
  20     cfg-changed
  21     drop ;