1 ! Copyright (C) 2008 Slava Pestov.
2 ! See http://factorcode.org/license.txt for BSD license.
3 USING: fry accessors namespaces assocs deques search-deques
4 dlists kernel sequences compiler.utilities words sets
5 stack-checker.branches compiler.tree compiler.tree.def-use
6 compiler.tree.combinators ;
7 IN: compiler.tree.dead-code.liveness
13 : live-value? ( value -- ? ) live-values get at ;
15 : look-at-value ( values -- ) work-list get push-front ;
17 : look-at-values ( values -- ) work-list get push-all-front ;
19 : look-at-inputs ( node -- ) in-d>> look-at-values ;
21 : init-dead-code ( -- )
22 <hashed-dlist> work-list set
23 H{ { +bottom+ f } } clone live-values set ;
25 GENERIC: mark-live-values* ( node -- )
27 : mark-live-values ( nodes -- nodes )
28 dup [ mark-live-values* ] each-node ; inline
30 M: node mark-live-values* drop ;
32 GENERIC: compute-live-values* ( value node -- )
34 M: node compute-live-values* 2drop ;
36 : iterate-live-values ( value -- )
37 dup live-values get key? [
40 dup live-values get conjoin
41 dup defined-by compute-live-values*
44 : compute-live-values ( -- )
45 work-list get [ iterate-live-values ] slurp-deque ;
47 GENERIC: remove-dead-code* ( node -- node' )
49 M: node remove-dead-code* ;
51 : (remove-dead-code) ( nodes -- nodes' )
52 [ remove-dead-code* ] map-flat ;