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

60 lines
1.7 KiB
Factor

! Copyright (C) 2008, 2010 Slava Pestov.
! See http://factorcode.org/license.txt for BSD license.
USING: namespaces arrays assocs kernel accessors
sorting sets sequences locals
cpu.architecture
sequences.deep
compiler.cfg
compiler.cfg.rpo
compiler.cfg.def-use
compiler.cfg.utilities
compiler.cfg.instructions
compiler.cfg.value-numbering.alien
compiler.cfg.value-numbering.comparisons
compiler.cfg.value-numbering.graph
compiler.cfg.value-numbering.math
compiler.cfg.value-numbering.rewrite
compiler.cfg.value-numbering.slots
compiler.cfg.value-numbering.misc
compiler.cfg.value-numbering.expressions ;
IN: compiler.cfg.value-numbering
GENERIC: process-instruction ( insn -- insn' )
: redundant-instruction ( insn vn -- insn' )
[ dst>> ] dip [ swap set-vn ] [ <copy> ] 2bi ;
:: useful-instruction ( insn expr -- insn' )
insn dst>> :> vn
vn vn vregs>vns get set-at
vn expr exprs>vns get set-at
insn vn vns>insns get set-at
insn ;
: check-redundancy ( insn -- insn' )
dup >expr dup exprs>vns get at
[ redundant-instruction ] [ useful-instruction ] ?if ;
M: insn process-instruction
dup rewrite [ process-instruction ] [ ] ?if ;
M: foldable-insn process-instruction
dup rewrite
[ process-instruction ]
[ dup defs-vregs length 1 = [ check-redundancy ] when ] ?if ;
M: ##copy process-instruction
dup [ src>> vreg>vn ] [ dst>> ] bi set-vn ;
M: array process-instruction
[ process-instruction ] map ;
: value-numbering-step ( insns -- insns' )
init-value-graph
[ process-instruction ] map flatten ;
: value-numbering ( cfg -- cfg )
dup [ value-numbering-step ] simple-optimization
cfg-changed predecessors-changed ;