1 ! Copyright (C) 2009 Doug Coleman, Slava Pestov.
2 ! See http://factorcode.org/license.txt for BSD license.
3 USING: accessors combinators.short-circuit kernel math math.order
4 sequences assocs namespaces vectors fry arrays splitting
5 compiler.cfg.def-use compiler.cfg compiler.cfg.rpo
6 compiler.cfg.renaming compiler.cfg.instructions compiler.cfg.utilities ;
7 IN: compiler.cfg.branch-splitting
9 : clone-instructions ( insns -- insns' )
10 [ clone dup fresh-insn-temps ] map ;
12 : clone-basic-block ( bb -- bb' )
13 ! The new block gets the same RPO number as the old one.
14 ! This is just to make 'back-edge?' work.
17 [ instructions>> clone-instructions >>instructions ]
18 [ successors>> clone >>successors ]
22 : new-blocks ( bb -- copies )
24 [ clone-basic-block ] dip
25 1vector >>predecessors
28 : update-predecessor-successor ( pred copy old-bb -- )
30 [ _ _ 3dup nip eq? [ drop nip ] [ 2drop ] if ] map
31 ] change-successors drop ;
33 : update-predecessor-successors ( copies old-bb -- )
34 [ predecessors>> swap ] keep
35 '[ _ update-predecessor-successor ] 2each ;
37 : update-successor-predecessor ( copies old-bb succ -- )
39 swap 1array split swap join V{ } like
40 ] change-predecessors drop ;
42 : update-successor-predecessors ( copies old-bb -- )
44 update-successor-predecessor
47 : split-branch ( bb -- )
49 [ update-predecessor-successors ]
50 [ update-successor-predecessors ]
53 UNION: irrelevant ##peek ##replace ##inc-d ##inc-r ;
55 : split-instructions? ( insns -- ? ) [ irrelevant? not ] count 5 <= ;
57 : short-tail-block? ( bb -- ? )
58 [ successors>> empty? ] [ instructions>> length 2 = ] bi and ;
60 : short-block? ( bb -- ? )
61 ! If block is empty, always split
62 [ predecessors>> length ] [ instructions>> length 1 - ] bi * 10 <= ;
64 : cond-cond-block? ( bb -- ? )
66 [ predecessors>> length 2 = ]
67 [ successors>> length 2 = ]
68 [ instructions>> length 20 <= ]
71 : split-branch? ( bb -- ? )
72 dup loop-entry? [ drop f ] [
73 dup predecessors>> length 1 <= [ drop f ] [
82 : split-branches ( cfg -- cfg' )
84 dup split-branch? [ split-branch ] [ drop ] if