1 ! Copyright (C) 2008, 2010 Slava Pestov.
2 ! See http://factorcode.org/license.txt for BSD license.
3 USING: namespaces kernel assocs accessors locals sequences math
4 math.order fry combinators binary-search
5 compiler.cfg.instructions compiler.cfg.registers
6 compiler.cfg.def-use compiler.cfg.liveness
7 compiler.cfg.linearization.order
10 IN: compiler.cfg.linear-scan.live-intervals
12 TUPLE: live-range from to ;
14 C: <live-range> live-range
16 SYMBOLS: +def+ +use+ +memory+ ;
18 TUPLE: vreg-use rep n type ;
20 C: <vreg-use> vreg-use
24 reg spill-to reload-from
28 : first-use ( live-interval -- use ) uses>> first ; inline
30 : last-use ( live-interval -- use ) uses>> last ; inline
32 GENERIC: covers? ( insn# obj -- ? )
34 M: f covers? 2drop f ;
36 M: live-range covers? [ from>> ] [ to>> ] bi between? ;
38 M: live-interval covers? ( insn# live-interval -- ? )
43 [ drop ] [ [ from>> <=> ] with search nip ] 2bi
47 : add-new-range ( from to live-interval -- )
48 [ <live-range> ] dip ranges>> push ;
50 : shorten-range ( n live-interval -- )
52 [ dupd add-new-range ] [ ranges>> last (>>from) ] if ;
54 : extend-range ( from to live-range -- )
60 : extend-range? ( to live-interval -- ? )
61 ranges>> [ drop f ] [ last from>> >= ] if-empty ;
63 : add-range ( from to live-interval -- )
65 [ extend-range ] [ add-new-range ] if ;
67 :: add-use ( rep n type live-interval -- )
70 live-interval uses>> push
73 : <live-interval> ( vreg reg-class -- live-interval )
80 : block-from ( bb -- n ) instructions>> first insn#>> 1 - ;
82 : block-to ( bb -- n ) instructions>> last insn#>> ;
86 ! Mapping from vreg to live-interval
87 SYMBOL: live-intervals
89 : live-interval ( vreg -- live-interval )
90 live-intervals get [ dup rep-of reg-class-of <live-interval> ] cache ;
92 GENERIC: compute-live-intervals* ( insn -- )
94 M: insn compute-live-intervals* drop ;
96 :: handle-output ( vreg n type -- )
98 vreg live-interval :> live-interval
100 n live-interval shorten-range
101 rep n type live-interval add-use ;
103 :: handle-input ( vreg n type -- )
105 vreg live-interval :> live-interval
107 from get n live-interval add-range
108 rep n type live-interval add-use ;
110 :: handle-temp ( vreg n -- )
112 vreg live-interval :> live-interval
114 n n live-interval add-range
115 rep n +def+ live-interval add-use ;
117 M:: vreg-insn compute-live-intervals* ( insn -- )
120 insn defs-vreg [ n +def+ handle-output ] when*
121 insn uses-vregs [ n +use+ handle-input ] each
122 insn temp-vregs [ n handle-temp ] each ;
124 M:: clobber-insn compute-live-intervals* ( insn -- )
127 insn defs-vreg [ n +use+ handle-output ] when*
128 insn uses-vregs [ n +memory+ handle-input ] each
129 insn temp-vregs [ n handle-temp ] each ;
131 : handle-live-out ( bb -- )
132 live-out dup assoc-empty? [ drop ] [
133 [ from get to get ] dip keys
134 [ live-interval add-range ] with with each
137 ! A location where all registers have to be spilled
138 TUPLE: sync-point n ;
140 C: <sync-point> sync-point
142 ! Sequence of sync points
145 GENERIC: compute-sync-points* ( insn -- )
147 M: clobber-insn compute-sync-points*
148 insn#>> <sync-point> sync-points get push ;
150 M: insn compute-sync-points* drop ;
152 : compute-live-intervals-step ( bb -- )
154 [ block-from from set ]
158 instructions>> <reversed> [
159 [ compute-live-intervals* ]
160 [ compute-sync-points* ]
166 : init-live-intervals ( -- )
167 H{ } clone live-intervals set
168 V{ } clone sync-points set ;
170 : compute-start/end ( live-interval -- )
171 dup ranges>> [ first from>> ] [ last to>> ] bi
172 [ >>start ] [ >>end ] bi* drop ;
174 ERROR: bad-live-interval live-interval ;
176 : check-start ( live-interval -- )
177 dup start>> -1 = [ bad-live-interval ] [ drop ] if ;
179 : finish-live-intervals ( live-intervals -- seq )
180 ! Since live intervals are computed in a backward order, we have
181 ! to reverse some sequences, and compute the start and end.
184 [ ranges>> reverse! drop ]
185 [ uses>> reverse! drop ]
186 [ compute-start/end ]
191 : compute-live-intervals ( cfg -- live-intervals sync-points )
193 linearization-order <reversed> [ compute-live-intervals-step ] each
194 live-intervals get finish-live-intervals
197 : relevant-ranges ( interval1 interval2 -- ranges1 ranges2 )
198 [ [ ranges>> ] bi@ ] [ nip start>> ] 2bi '[ to>> _ >= ] filter ;
200 : intersect-live-range ( range1 range2 -- n/f )
201 2dup [ from>> ] bi@ > [ swap ] when
202 2dup [ to>> ] [ from>> ] bi* >= [ nip from>> ] [ 2drop f ] if ;
204 : intersect-live-ranges ( ranges1 ranges2 -- n )
206 { [ over empty? ] [ 2drop f ] }
207 { [ dup empty? ] [ 2drop f ] }
209 2dup [ first ] bi@ intersect-live-range dup [ 2nip ] [
211 2dup [ first from>> ] bi@ <
212 [ [ rest-slice ] dip ] [ rest-slice ] if
213 intersect-live-ranges
218 : intervals-intersect? ( interval1 interval2 -- ? )
219 relevant-ranges intersect-live-ranges >boolean ; inline