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 compiler.cfg.utilities
10 cpu.architecture 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 ]
31 [ [ dup dup value-of ] dip <vreg-info> 1array ] assoc-map
34 V{ } clone copies set ;
36 : coalesce-elements ( merged vreg1 vreg2 -- )
37 ! delete leader1's class, and set leader2's class to merged.
38 class-element-map get [ delete-at ] [ set-at ] bi-curry bi* ;
40 : coalesce-vregs ( merged leader1 leader2 -- )
41 2dup swap leader-map get set-at coalesce-elements ;
43 GENERIC: prepare-insn ( insn -- )
45 : maybe-eliminate-copy-later ( dst src -- )
46 2array copies get push ;
48 M: insn prepare-insn drop ;
50 M: alien-call-insn prepare-insn drop ;
52 M: vreg-insn prepare-insn
53 [ temp-vregs [ leader-map get conjoin ] each ]
55 [ defs-vregs ] [ uses-vregs ] bi
56 2dup [ empty? not ] both? [
58 2dup [ rep-of reg-class-of ] bi@ eq?
59 [ maybe-eliminate-copy-later ] [ 2drop ] if
63 M: ##copy prepare-insn
64 [ dst>> ] [ src>> ] bi maybe-eliminate-copy-later ;
66 M: ##parallel-copy prepare-insn
67 values>> [ first2 maybe-eliminate-copy-later ] each ;
69 : leaders ( vreg1 vreg2 -- vreg1' vreg2' )
72 : vregs-interfere? ( vreg1 vreg2 -- merged/f ? )
73 [ class-elements ] bi@ sets-interfere? ;
75 ERROR: vregs-shouldn't-interfere vreg1 vreg2 ;
77 :: must-eliminate-copy ( vreg1 vreg2 -- )
80 vreg1 vreg2 vregs-interfere?
81 [ vreg1 vreg2 vregs-shouldn't-interfere ]
82 [ vreg1 vreg2 coalesce-vregs ]
86 M: ##tagged>integer prepare-insn
87 [ dst>> ] [ src>> ] bi leaders must-eliminate-copy ;
90 [ dst>> ] [ inputs>> values ] bi
91 [ leaders must-eliminate-copy ] with each ;
93 : prepare-coalescing ( cfg -- )
95 [ [ prepare-insn ] each ] simple-analysis ;
97 :: maybe-eliminate-copy ( vreg1 vreg2 -- )
98 ! Eliminate a copy if possible.
100 vreg1 vreg2 vregs-interfere?
101 [ drop ] [ vreg1 vreg2 coalesce-vregs ] if
104 : process-copies ( copies -- )
105 [ leaders maybe-eliminate-copy ] assoc-each ;
107 : perform-coalescing ( cfg -- )
108 prepare-coalescing copies get process-copies ;
110 GENERIC: cleanup-insn ( insn -- )
112 : useful-copy? ( insn -- ? )
113 [ dst>> ] [ src>> ] bi leaders = not ; inline
115 M: ##copy cleanup-insn
116 dup useful-copy? [ , ] [ drop ] if ;
118 M: ##parallel-copy cleanup-insn
119 values>> [ leaders ] assoc-map [ first2 = not ] filter
120 parallel-copy-rep % ;
122 M: ##tagged>integer cleanup-insn
123 dup useful-copy? [ , ] [ drop ] if ;
125 M: ##phi cleanup-insn drop ;
127 M: insn cleanup-insn , ;
129 : cleanup-cfg ( cfg -- )
130 [ [ [ cleanup-insn ] each ] V{ } make ] simple-optimization ;
134 : destruct-ssa ( cfg -- )