1 ! Copyright (C) 2008, 2010 Slava Pestov.
2 ! See http://factorcode.org/license.txt for BSD license.
3 USING: accessors arrays assocs classes.algebra combinators
4 compiler.tree compiler.tree.dead-code.liveness
5 compiler.tree.propagation.info fry kernel locals math
6 math.private namespaces sequences stack-checker.backend
7 stack-checker.dependencies words ;
8 IN: compiler.tree.dead-code.simple
10 : flushable-call? ( #call -- ? )
11 dup word>> dup flushable? [
12 "input-classes" word-prop dup [
13 [ node-input-infos ] dip
14 [ [ class>> ] dip class<= ] 2all?
18 M: #call mark-live-values*
19 dup flushable-call? [ drop ] [ look-at-inputs ] if ;
21 M: #alien-node mark-live-values* look-at-inputs ;
23 M: #return mark-live-values* look-at-inputs ;
25 : look-at-mapping ( value inputs outputs -- )
26 [ index ] dip over [ nth look-at-value ] [ 2drop ] if ;
28 M: #copy compute-live-values*
29 ! If the output of a copy is live, then the corresponding
31 [ out-d>> ] [ in-d>> ] bi look-at-mapping ;
33 M: #call compute-live-values* nip look-at-inputs ;
35 M: #shuffle compute-live-values*
36 mapping>> at look-at-value ;
38 M: #alien-node compute-live-values* nip look-at-inputs ;
40 : filter-mapping ( assoc -- assoc' )
41 live-values get '[ drop _ key? ] assoc-filter ;
43 : filter-corresponding ( new old -- old' )
44 ! Remove elements from 'old' if the element with the same
45 ! index in 'new' is dead.
46 zip filter-mapping values ;
48 : filter-live ( values -- values' )
49 dup empty? [ live-values get '[ _ at ] filter ] unless ;
51 :: drop-values ( inputs outputs mapping-keys mapping-values -- #shuffle )
57 filter-corresponding zip <#data-shuffle> ; inline
59 :: drop-dead-values ( outputs -- #shuffle )
60 outputs length make-values :> new-outputs
61 outputs filter-live :> live-outputs
68 : drop-dead-outputs ( node -- #shuffle )
69 dup out-d>> drop-dead-values [ in-d>> >>out-d drop ] keep ;
71 : some-outputs-dead? ( #call -- ? )
72 out-d>> [ live-value? not ] any? ;
74 : maybe-drop-dead-outputs ( node -- nodes )
75 dup some-outputs-dead? [
76 dup drop-dead-outputs 2array
79 M: #introduce remove-dead-code* ( #introduce -- nodes )
80 maybe-drop-dead-outputs ;
82 M: #push remove-dead-code*
83 dup out-d>> first live-value? [ drop f ] unless ;
85 : dead-flushable-call? ( #call -- ? )
87 out-d>> [ live-value? not ] all?
90 : remove-flushable-call ( #call -- node )
91 [ word>> add-depends-on-flushable ]
92 [ in-d>> <#drop> remove-dead-code* ]
95 : define-simplifications ( word seq -- )
96 "simplifications" set-word-prop ;
102 } define-simplifications
106 { { t f } fixnum-mod }
107 } define-simplifications
111 { { t f } bignum-mod }
112 } define-simplifications
114 : out-d-matches? ( out-d seq -- ? )
115 [ swap live-value? xor ] 2all? ;
117 : (simplify-call) ( #call -- new-word/f )
118 [ out-d>> ] [ word>> "simplifications" word-prop ] bi
119 [ first out-d-matches? ] with find nip dup [ second ] when ;
121 : simplify-call ( #call -- nodes )
122 dup (simplify-call) [
123 >>word [ filter-live ] change-out-d
125 maybe-drop-dead-outputs
128 M: #call remove-dead-code*
130 { [ dup dead-flushable-call? ] [ remove-flushable-call ] }
131 { [ dup word>> "simplifications" word-prop ] [ simplify-call ] }
132 [ maybe-drop-dead-outputs ]
135 M: #shuffle remove-dead-code*
136 [ filter-live ] change-in-d
137 [ filter-live ] change-out-d
138 [ filter-live ] change-in-r
139 [ filter-live ] change-out-r
140 [ filter-mapping ] change-mapping
141 dup [ in-d>> empty? ] [ in-r>> empty? ] bi and [ drop f ] when ;
143 M: #copy remove-dead-code*
144 [ in-d>> ] [ out-d>> ] bi
145 2dup swap zip <#data-shuffle>
148 M: #terminate remove-dead-code*
149 [ filter-live ] change-in-d
150 [ filter-live ] change-in-r ;
152 M: #alien-node remove-dead-code*
153 maybe-drop-dead-outputs ;
155 M: #alien-callback remove-dead-code*
156 [ (remove-dead-code) ] change-child ;