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 SYMBOL: class-element-map
16 : class-elements ( vreg -- elts ) class-element-map get at ;
20 ! Sequence of vreg pairs
23 : value-of ( vreg -- value )
24 dup insn-of dup ##tagged>integer? [ nip src>> ] [ drop ] if ;
26 : init-coalescing ( -- )
28 [ keys unique leader-map set ]
30 [ [ dup dup value-of ] dip <vreg-info> 1array ] assoc-map
33 V{ } clone copies set ;
35 : coalesce-elements ( merged vreg1 vreg2 -- )
36 ! delete leader1's class, and set leader2's class to merged.
37 class-element-map get [ delete-at ] [ set-at ] bi-curry bi* ;
39 : coalesce-vregs ( merged leader1 leader2 -- )
40 2dup swap leader-map get set-at coalesce-elements ;
42 GENERIC: prepare-insn ( insn -- )
44 : maybe-eliminate-copy-later ( dst src -- )
45 2array copies get push ;
47 M: insn prepare-insn drop ;
49 M: alien-call-insn prepare-insn drop ;
51 M: vreg-insn prepare-insn
52 [ temp-vregs [ leader-map get conjoin ] each ]
54 [ defs-vregs ] [ uses-vregs ] bi
55 2dup [ empty? not ] both? [
57 2dup [ rep-of reg-class-of ] bi@ eq?
58 [ maybe-eliminate-copy-later ] [ 2drop ] if
62 M: ##copy prepare-insn
63 [ dst>> ] [ src>> ] bi maybe-eliminate-copy-later ;
65 M: ##parallel-copy prepare-insn
66 values>> [ first2 maybe-eliminate-copy-later ] each ;
68 : leaders ( vreg1 vreg2 -- vreg1' vreg2' )
71 : vregs-interfere? ( vreg1 vreg2 -- merged/f ? )
72 [ class-elements ] bi@ sets-interfere? ;
74 ERROR: vregs-shouldn't-interfere vreg1 vreg2 ;
76 :: must-eliminate-copy ( vreg1 vreg2 -- )
79 vreg1 vreg2 vregs-interfere?
80 [ vreg1 vreg2 vregs-shouldn't-interfere ]
81 [ vreg1 vreg2 coalesce-vregs ]
85 M: ##tagged>integer prepare-insn
86 [ dst>> ] [ src>> ] bi leaders must-eliminate-copy ;
89 [ dst>> ] [ inputs>> values ] bi
90 [ leaders must-eliminate-copy ] with each ;
92 : prepare-coalescing ( cfg -- )
94 [ [ prepare-insn ] each ] simple-analysis ;
96 :: maybe-eliminate-copy ( vreg1 vreg2 -- )
97 ! Eliminate a copy if possible.
99 vreg1 vreg2 vregs-interfere?
100 [ drop ] [ vreg1 vreg2 coalesce-vregs ] if
103 : process-copies ( copies -- )
104 [ leaders maybe-eliminate-copy ] assoc-each ;
106 : perform-coalescing ( cfg -- )
107 prepare-coalescing copies get process-copies ;
109 GENERIC: cleanup-insn ( insn -- )
111 : useful-copy? ( insn -- ? )
112 [ dst>> ] [ src>> ] bi leaders = not ; inline
114 M: ##copy cleanup-insn
115 dup useful-copy? [ , ] [ drop ] if ;
117 M: ##parallel-copy cleanup-insn
118 values>> [ leaders ] assoc-map [ first2 = not ] filter
119 parallel-copy-rep % ;
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 -- )
134 H{ } clone leader-map set