1 ! Copyright (C) 2008, 2010 Slava Pestov.
2 ! See http://factorcode.org/license.txt for BSD license.
3 USING: accessors assocs binary-search combinators
4 compiler.cfg.def-use compiler.cfg.instructions
5 compiler.cfg.linearization compiler.cfg.liveness
6 compiler.cfg.registers compiler.cfg.ssa.destruction.leaders
7 cpu.architecture fry kernel locals math math.order namespaces
9 IN: compiler.cfg.linear-scan.live-intervals
11 TUPLE: live-range from to ;
13 C: <live-range> live-range
15 TUPLE: vreg-use n def-rep use-rep spill-slot? ;
17 : <vreg-use> ( n -- vreg-use ) vreg-use new swap >>n ;
19 TUPLE: live-interval-state
21 reg spill-to spill-rep reload-from reload-rep
25 : first-use ( live-interval -- use ) uses>> first ; inline
27 : last-use ( live-interval -- use ) uses>> last ; inline
29 : new-use ( insn# uses -- use )
30 [ <vreg-use> dup ] dip push ;
32 : last-use? ( insn# uses -- use/f )
33 [ drop f ] [ last [ n>> = ] keep and ] if-empty ;
35 :: (add-use) ( insn# live-interval spill-slot? -- use )
36 live-interval uses>> :> uses
37 insn# uses last-use? [ insn# uses new-use ] unless*
38 spill-slot? [ t >>spill-slot? ] when ;
40 GENERIC: covers? ( insn# obj -- ? )
42 M: f covers? 2drop f ;
44 M: live-range covers? [ from>> ] [ to>> ] bi between? ;
46 M: live-interval-state covers? ( insn# live-interval -- ? )
51 [ drop ] [ [ from>> <=> ] with search nip ] 2bi
55 : (find-use) ( insn# live-interval -- vreg-use )
56 uses>> [ n>> <=> ] with search nip ;
58 :: find-use ( insn# live-interval -- vreg-use )
59 insn# live-interval (find-use)
60 dup [ dup n>> insn# = [ drop f ] unless ] when ;
62 : add-new-range ( from to live-interval -- )
63 [ <live-range> ] dip ranges>> push ;
65 : shorten-range ( n live-interval -- )
67 [ dupd add-new-range ] [ ranges>> last from<< ] if ;
69 : extend-range ( from to live-range -- )
75 : extend-range? ( to live-interval -- ? )
76 ranges>> [ drop f ] [ last from>> >= ] if-empty ;
78 : add-range ( from to live-interval -- )
80 [ extend-range ] [ add-new-range ] if ;
82 : <live-interval> ( vreg reg-class -- live-interval )
83 \ live-interval-state new
89 : block-from ( bb -- n ) instructions>> first insn#>> 1 - ;
91 : block-to ( bb -- n ) instructions>> last insn#>> ;
95 ! Mapping from vreg to live-interval
96 SYMBOL: live-intervals
98 : live-interval ( vreg -- live-interval )
99 leader live-intervals get
100 [ dup rep-of reg-class-of <live-interval> ] cache ;
102 GENERIC: compute-live-intervals* ( insn -- )
104 M: insn compute-live-intervals* drop ;
106 :: record-def ( vreg n spill-slot? -- )
107 vreg live-interval :> live-interval
109 n live-interval shorten-range
110 n live-interval spill-slot? (add-use) vreg rep-of >>def-rep drop ;
112 :: record-use ( vreg n spill-slot? -- )
113 vreg live-interval :> live-interval
115 from get n live-interval add-range
116 n live-interval spill-slot? (add-use) vreg rep-of >>use-rep drop ;
118 :: record-temp ( vreg n -- )
119 vreg live-interval :> live-interval
121 n n live-interval add-range
122 n live-interval f (add-use) vreg rep-of >>def-rep drop ;
124 M: vreg-insn compute-live-intervals* ( insn -- )
126 [ [ defs-vregs ] dip '[ _ f record-def ] each ]
127 [ [ uses-vregs ] dip '[ _ f record-use ] each ]
128 [ [ temp-vregs ] dip '[ _ record-temp ] each ]
131 ! Extend lifetime intervals of base pointers, so that their
132 ! values are available even if the base pointer is never used
135 GENERIC: uses-vregs* ( insn -- seq )
137 M: gc-map-insn uses-vregs*
138 [ uses-vregs ] [ gc-map>> derived-roots>> values ] bi append ;
140 M: vreg-insn uses-vregs* uses-vregs ;
142 M: insn uses-vregs* drop f ;
144 M: clobber-insn compute-live-intervals* ( insn -- )
146 [ [ defs-vregs ] dip '[ _ f record-def ] each ]
147 [ [ uses-vregs* ] dip '[ _ t record-use ] each ]
148 [ [ temp-vregs ] dip '[ _ record-temp ] each ]
151 M: hairy-clobber-insn compute-live-intervals* ( insn -- )
153 [ [ defs-vregs ] dip '[ _ t record-def ] each ]
154 [ [ uses-vregs* ] dip '[ _ t record-use ] each ]
155 [ [ temp-vregs ] dip '[ _ record-temp ] each ]
158 : handle-live-out ( bb -- )
159 live-out dup assoc-empty? [ drop ] [
160 [ from get to get ] dip keys
161 [ live-interval add-range ] 2with each
164 ! A location where all registers have to be spilled
165 TUPLE: sync-point n keep-dst? ;
167 C: <sync-point> sync-point
169 ! Sequence of sync points
172 GENERIC: compute-sync-points* ( insn -- )
174 M: hairy-clobber-insn compute-sync-points*
175 insn#>> f <sync-point> sync-points get push ;
177 M: clobber-insn compute-sync-points*
178 insn#>> t <sync-point> sync-points get push ;
180 M: insn compute-sync-points* drop ;
182 : compute-live-intervals-step ( bb -- )
183 dup kill-block?>> [ drop ] [
185 [ block-from from set ]
189 instructions>> <reversed> [
190 [ compute-live-intervals* ]
191 [ compute-sync-points* ]
198 : init-live-intervals ( -- )
199 H{ } clone live-intervals set
200 V{ } clone sync-points set ;
202 : compute-start/end ( live-interval -- )
203 dup ranges>> [ first from>> ] [ last to>> ] bi
204 [ >>start ] [ >>end ] bi* drop ;
206 ERROR: bad-live-interval live-interval ;
208 : check-start ( live-interval -- )
209 dup start>> -1 = [ bad-live-interval ] [ drop ] if ;
211 : finish-live-intervals ( live-intervals -- seq )
212 ! Since live intervals are computed in a backward order, we have
213 ! to reverse some sequences, and compute the start and end.
216 [ [ { } like reverse! ] change-ranges drop ]
217 [ [ { } like reverse! ] change-uses drop ]
218 [ compute-start/end ]
223 : compute-live-intervals ( cfg -- live-intervals sync-points )
225 linearization-order <reversed> [ compute-live-intervals-step ] each
226 live-intervals get finish-live-intervals
229 : relevant-ranges ( interval1 interval2 -- ranges1 ranges2 )
230 [ [ ranges>> ] bi@ ] [ nip start>> ] 2bi '[ to>> _ >= ] filter ;
232 : intersect-live-range ( range1 range2 -- n/f )
233 2dup [ from>> ] bi@ > [ swap ] when
234 2dup [ to>> ] [ from>> ] bi* >= [ nip from>> ] [ 2drop f ] if ;
236 : intersect-live-ranges ( ranges1 ranges2 -- n )
238 { [ over empty? ] [ 2drop f ] }
239 { [ dup empty? ] [ 2drop f ] }
241 2dup [ first ] bi@ intersect-live-range dup [ 2nip ] [
243 2dup [ first from>> ] bi@ <
244 [ [ rest-slice ] dip ] [ rest-slice ] if
245 intersect-live-ranges
250 : intervals-intersect? ( interval1 interval2 -- ? )
251 relevant-ranges intersect-live-ranges >boolean ; inline