1 ! Copyright (C) 2009, 2011 Slava Pestov.
2 ! See http://factorcode.org/license.txt for BSD license.
3 USING: accessors arrays assocs combinators compiler.cfg.def-use
4 compiler.cfg.dominance compiler.cfg.instructions
5 compiler.cfg.liveness compiler.cfg.parallel-copy
6 compiler.cfg.registers compiler.cfg.rpo compiler.cfg.ssa.cssa
7 compiler.cfg.ssa.destruction.leaders
8 compiler.cfg.ssa.interference
9 compiler.cfg.ssa.interference.live-ranges cpu.architecture
10 kernel locals make namespaces sequences sets ;
11 FROM: namespaces => set ;
12 IN: compiler.cfg.ssa.destruction
14 ! Maps leaders to equivalence class elements.
15 SYMBOL: class-element-map
17 : class-elements ( vreg -- elts ) class-element-map get at ;
21 ! Sequence of vreg pairs
24 : value-of ( vreg -- value )
25 dup insn-of dup ##tagged>integer? [ nip src>> ] [ drop ] if ;
27 : init-coalescing ( -- )
29 [ [ drop dup ] assoc-map leader-map set ]
30 [ [ [ dup dup value-of ] dip <vreg-info> 1array ] assoc-map class-element-map set ] bi
31 V{ } clone copies set ;
33 : coalesce-leaders ( vreg1 vreg2 -- )
34 ! leader2 becomes the leader.
35 swap leader-map get set-at ;
37 : coalesce-elements ( merged vreg1 vreg2 -- )
38 ! delete leader1's class, and set leader2's class to merged.
39 class-element-map get [ delete-at ] [ set-at ] bi-curry bi* ;
41 : coalesce-vregs ( merged leader1 leader2 -- )
42 [ coalesce-leaders ] [ coalesce-elements ] 2bi ;
44 GENERIC: prepare-insn ( insn -- )
46 : maybe-eliminate-copy-later ( dst src -- )
47 2array copies get push ;
49 M: insn prepare-insn drop ;
51 M: alien-call-insn prepare-insn drop ;
53 M: vreg-insn prepare-insn
54 [ temp-vregs [ leader-map get conjoin ] each ]
56 [ defs-vregs ] [ uses-vregs ] bi
57 2dup [ empty? not ] both? [
59 2dup [ rep-of reg-class-of ] bi@ eq?
60 [ maybe-eliminate-copy-later ] [ 2drop ] if
64 M: ##copy prepare-insn
65 [ dst>> ] [ src>> ] bi maybe-eliminate-copy-later ;
67 M: ##parallel-copy prepare-insn
68 values>> [ first2 maybe-eliminate-copy-later ] each ;
70 : leaders ( vreg1 vreg2 -- vreg1' vreg2' )
73 : vregs-interfere? ( vreg1 vreg2 -- merged/f ? )
74 [ class-elements ] bi@ sets-interfere? ;
76 ERROR: vregs-shouldn't-interfere vreg1 vreg2 ;
78 :: must-eliminate-copy ( vreg1 vreg2 -- )
81 vreg1 vreg2 vregs-interfere?
82 [ vreg1 vreg2 vregs-shouldn't-interfere ]
83 [ vreg1 vreg2 coalesce-vregs ]
87 M: ##tagged>integer prepare-insn
88 [ dst>> ] [ src>> ] bi leaders must-eliminate-copy ;
91 [ dst>> ] [ inputs>> values ] bi
92 [ leaders must-eliminate-copy ] with each ;
94 : prepare-coalescing ( cfg -- )
96 [ [ prepare-insn ] each ] simple-analysis ;
98 :: maybe-eliminate-copy ( vreg1 vreg2 -- )
99 ! Eliminate a copy if possible.
101 vreg1 vreg2 vregs-interfere?
102 [ drop ] [ vreg1 vreg2 coalesce-vregs ] if
105 : process-copies ( -- )
106 copies get [ leaders maybe-eliminate-copy ] assoc-each ;
108 GENERIC: cleanup-insn ( insn -- )
110 : useful-copy? ( insn -- ? )
111 [ dst>> ] [ src>> ] bi leaders eq? not ; inline
113 M: ##copy cleanup-insn
114 dup useful-copy? [ , ] [ drop ] if ;
116 M: ##parallel-copy cleanup-insn
118 [ first2 leaders 2array ] map [ first2 eq? not ] filter
119 [ parallel-copy-rep % ] unless-empty ;
121 M: ##tagged>integer cleanup-insn
122 dup useful-copy? [ , ] [ drop ] if ;
124 M: ##phi cleanup-insn drop ;
126 M: insn cleanup-insn , ;
128 : cleanup-cfg ( cfg -- )
129 [ [ [ cleanup-insn ] each ] V{ } make ] simple-optimization ;
133 : destruct-ssa ( cfg -- )
139 [ compute-live-sets ]
140 [ compute-live-ranges ]
141 [ prepare-coalescing ]
142 [ drop process-copies ]
144 [ compute-live-sets ]