1 ! Copyright (C) 2008, 2009 Slava Pestov, Daniel Ehrenberg.
2 ! See http://factorcode.org/license.txt for BSD license.
3 USING: accessors assocs combinators.short-circuit
4 compiler.cfg.instructions compiler.cfg.rpo kernel namespaces
6 IN: compiler.cfg.write-barrier
8 SYMBOL: fresh-allocations
10 SYMBOL: mutated-objects
12 GENERIC: eliminate-write-barrier ( insn -- ? )
14 M: ##allot eliminate-write-barrier
15 dst>> fresh-allocations get conjoin t ;
17 M: ##set-slot eliminate-write-barrier
18 obj>> mutated-objects get conjoin t ;
20 M: ##set-slot-imm eliminate-write-barrier
21 obj>> mutated-objects get conjoin t ;
23 : needs-write-barrier? ( insn -- ? )
24 { [ fresh-allocations get key? not ] [ mutated-objects get key? ] } 1&& ;
26 M: ##write-barrier eliminate-write-barrier
27 src>> needs-write-barrier? ;
29 M: ##write-barrier-imm eliminate-write-barrier
30 src>> needs-write-barrier? ;
32 M: ##copy eliminate-write-barrier
33 "Run copy propagation first" throw ;
35 M: insn eliminate-write-barrier drop t ;
37 : write-barriers-step ( bb -- )
38 H{ } clone fresh-allocations set
39 H{ } clone mutated-objects set
40 instructions>> [ eliminate-write-barrier ] filter! drop ;
42 : eliminate-write-barriers ( cfg -- cfg' )
43 dup [ write-barriers-step ] each-basic-block ;