factor/basis/compiler/cfg/liveness/liveness.factor

52 lines
1.5 KiB
Factor

! Copyright (C) 2009, 2010 Slava Pestov.
! See http://factorcode.org/license.txt for BSD license.
USING: kernel accessors assocs namespaces sequences sets
compiler.cfg.def-use compiler.cfg.dataflow-analysis
compiler.cfg.instructions compiler.cfg.registers
cpu.architecture ;
IN: compiler.cfg.liveness
! See http://en.wikipedia.org/wiki/Liveness_analysis
! Do not run after SSA construction; compiler.cfg.liveness.ssa
! should be used instead. The transfer-liveness word is used
! by SSA liveness too, so it handles ##phi instructions.
BACKWARD-ANALYSIS: live
GENERIC: visit-insn ( live-set insn -- live-set )
: kill-defs ( live-set insn -- live-set )
defs-vregs [ over delete-at ] each ; inline
: gen-uses ( live-set insn -- live-set )
uses-vregs [ over conjoin ] each ; inline
M: vreg-insn visit-insn [ kill-defs ] [ gen-uses ] bi ;
: fill-gc-map ( live-set insn -- live-set )
representations get [
gc-map>> over keys
[ rep-of tagged-rep? ] filter
>>gc-roots
] when
drop ;
M: gc-map-insn visit-insn
[ kill-defs ] [ fill-gc-map ] [ gen-uses ] tri ;
M: ##phi visit-insn kill-defs ;
M: insn visit-insn drop ;
: transfer-liveness ( live-set instructions -- live-set' )
[ clone ] [ <reversed> ] bi* [ visit-insn ] each ;
: local-live-in ( instructions -- live-set )
[ H{ } ] dip transfer-liveness keys ;
M: live-analysis transfer-set
drop instructions>> transfer-liveness ;
M: live-analysis join-sets
2drop assoc-combine ;