40 lines
1.1 KiB
Factor
40 lines
1.1 KiB
Factor
! Copyright (C) 2008, 2009 Slava Pestov.
|
|
! See http://factorcode.org/license.txt for BSD license.
|
|
USING: kernel accessors namespaces assocs sets sequences
|
|
compiler.cfg compiler.cfg.instructions compiler.cfg.rpo ;
|
|
IN: compiler.cfg.write-barrier
|
|
|
|
! Eliminate redundant write barrier hits.
|
|
|
|
! Objects which have already been marked, as well as
|
|
! freshly-allocated objects
|
|
SYMBOL: safe
|
|
|
|
! Objects which have been mutated
|
|
SYMBOL: mutated
|
|
|
|
GENERIC: eliminate-write-barrier ( insn -- ? )
|
|
|
|
M: ##allot eliminate-write-barrier
|
|
dst>> safe get conjoin t ;
|
|
|
|
M: ##write-barrier eliminate-write-barrier
|
|
src>> dup [ safe get key? not ] [ mutated get key? ] bi and
|
|
[ safe get conjoin t ] [ drop f ] if ;
|
|
|
|
M: ##set-slot eliminate-write-barrier
|
|
obj>> mutated get conjoin t ;
|
|
|
|
M: ##set-slot-imm eliminate-write-barrier
|
|
obj>> mutated get conjoin t ;
|
|
|
|
M: insn eliminate-write-barrier drop t ;
|
|
|
|
: write-barriers-step ( bb -- )
|
|
H{ } clone safe set
|
|
H{ } clone mutated set
|
|
instructions>> [ eliminate-write-barrier ] filter-here ;
|
|
|
|
: eliminate-write-barriers ( cfg -- cfg' )
|
|
dup [ write-barriers-step ] each-basic-block ;
|