basis/compiler/cfg/value-numbering/value-numbering.factor

   1 ! Copyright (C) 2008, 2009 Slava Pestov.
   2 ! See http://factorcode.org/license.txt for BSD license.
   3 USING: namespaces assocs kernel accessors
   4 sorting sets sequences
   5 compiler.cfg
   6 compiler.cfg.rpo
   7 compiler.cfg.instructions
   8 compiler.cfg.value-numbering.graph
   9 compiler.cfg.value-numbering.expressions
  10 compiler.cfg.value-numbering.simplify
  11 compiler.cfg.value-numbering.rewrite ;
  12 IN: compiler.cfg.value-numbering
  13
  14 ! Local value numbering. Predecessors must be recomputed after this
  15 : >copy ( insn -- insn/##copy )
  16     dup dst>> dup vreg>vn vn>vreg
  17     2dup eq? [ 2drop ] [ \ ##copy new-insn nip ] if ;
  18
  19 : rewrite-loop ( insn -- insn' )
  20     dup rewrite [ rewrite-loop ] [ ] ?if ;
  21
  22 GENERIC: process-instruction ( insn -- insn' )
  23
  24 M: ##flushable process-instruction
  25     dup rewrite
  26     [ process-instruction ]
  27     [ dup number-values >copy ] ?if ;
  28
  29 M: insn process-instruction
  30     dup rewrite
  31     [ process-instruction ] [ ] ?if ;
  32
  33 : value-numbering-step ( insns -- insns' )
  34     init-value-graph
  35     init-expressions
  36     [ process-instruction ] map ;
  37
  38 : value-numbering ( cfg -- cfg' )
  39     [ value-numbering-step ] local-optimization cfg-changed ;