-
-
Notifications
You must be signed in to change notification settings - Fork 373
/
Optimizer.nqp
2789 lines (2551 loc) Β· 109 KB
/
Optimizer.nqp
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
# This file contains a bunch of classes related to static optimization of Perl
# 6 programs. It takes place after we've done all of the stuff in the grammar
# and actions, which means CHECK time is over. Thus we're allowed to assume that
# lexpads are immutable, declarations are over and done with, multi candidate
# lists won't change and so forth.
use NQPP6QRegex;
use QAST;
use Perl6::Ops;
# A null QAST node, inserted when we want to eliminate something.
my $NULL := QAST::Op.new( :op<null> );
# Represents the current set of blocks we're in and thus the symbols they
# make available, and allows for queries over them.
my class Symbols {
# The nested blocks we're in; it's the lexical chain, essentially.
has @!block_stack;
# Some interesting scopes.
has $!GLOBALish;
has $!UNIT;
has $!SETTING;
# Cached setting lookups.
has %!SETTING_CACHE;
# Some interesting symbols.
has $!Mu;
has $!Any;
has $!Block;
has $!PseudoStash;
has $!Routine;
has $!Nil;
has $!Failure;
has $!Seq;
# Top routine, for faking it when optimizing post-inline.
has $!fake_top_routine;
# Constructs a new instance of the symbols handling class.
method new($compunit) {
my $obj := nqp::create(self);
$obj.BUILD($compunit);
$obj
}
method BUILD($compunit) {
@!block_stack := [$compunit[0]];
$!GLOBALish := $compunit.ann('GLOBALish');
$!UNIT := $compunit.ann('UNIT');
%!SETTING_CACHE := {};
unless nqp::istype($!UNIT, QAST::Block) {
nqp::die("Optimizer could not find UNIT");
}
nqp::push(@!block_stack, $!UNIT);
$!Mu := self.find_lexical('Mu');
$!Any := self.find_lexical('Any');
$!Block := self.find_lexical('Block');
$!PseudoStash := self.find_lexical('PseudoStash');
$!Routine := self.find_lexical('Routine');
$!Nil := self.find_lexical('Nil');
$!Failure := self.find_lexical('Failure');
$!Seq := self.find_lexical('Seq');
nqp::pop(@!block_stack);
}
# Block handling.
method push_block($block) {
nqp::push(@!block_stack, $block);
}
method pop_block() {
nqp::pop(@!block_stack)
}
method top_block() {
@!block_stack[+@!block_stack - 1]
}
method top_routine() {
return $!fake_top_routine if $!fake_top_routine;
my int $i := nqp::elems(@!block_stack);
while $i > 0 {
$i := $i - 1;
my $co := @!block_stack[$i].ann('code_object');
if nqp::istype($co, $!Routine) {
return $co;
}
}
NQPMu
}
method faking_top_routine($fake, $run) {
$!fake_top_routine := $fake;
my $result := $run();
$!fake_top_routine := NQPMu;
$result;
}
# Accessors for interesting symbols/scopes.
method GLOBALish() { $!GLOBALish }
method UNIT() { $!UNIT }
method Mu() { $!Mu }
method Any() { $!Any }
method Block() { $!Block }
method PseudoStash() { $!PseudoStash }
method Nil() { $!Nil }
method Failure() { $!Failure }
method Seq() { $!Seq }
# The following function is a nearly 1:1 copy of World.find_symbol.
# Finds a symbol that has a known value at compile time from the
# perspective of the current scope. Checks for lexicals, then if
# that fails tries package lookup.
method find_symbol(@name) {
# Make sure it's not an empty name.
unless +@name { nqp::die("Cannot look up empty name"); }
# GLOBAL is current view of global.
if +@name == 1 && @name[0] eq 'GLOBAL' {
return $!GLOBALish;
}
# If it's a single-part name, look through the lexical
# scopes.
if +@name == 1 {
my $final_name := @name[0];
my int $i := +@!block_stack;
while $i > 0 {
$i := $i - 1;
my %sym := @!block_stack[$i].symbol($final_name);
if +%sym {
return self.force_value(%sym, $final_name, 1);
}
}
}
# If it's a multi-part name, see if the containing package
# is a lexical somewhere. Otherwise we fall back to looking
# in GLOBALish.
my $result := $!GLOBALish;
if +@name >= 2 {
my $first := @name[0];
my int $i := +@!block_stack;
while $i > 0 {
$i := $i - 1;
my %sym := @!block_stack[$i].symbol($first);
if +%sym {
$result := self.force_value(%sym, $first, 1);
@name := nqp::clone(@name);
@name.shift();
$i := 0;
}
}
}
# Try to chase down the parts of the name.
for @name {
if nqp::existskey($result.WHO, ~$_) {
$result := ($result.WHO){$_};
}
else {
nqp::die("Could not locate compile-time value for symbol " ~
join('::', @name));
}
}
$result;
}
# Locates a lexical symbol and returns its compile time value. Dies if
# it does not exist.
method find_lexical($name) {
my int $i := +@!block_stack;
while $i > 0 {
$i := $i - 1;
my $block := @!block_stack[$i];
my %sym := $block.symbol($name);
if +%sym {
return self.force_value(%sym, $name, 1);
}
}
nqp::die("Optimizer: No lexical $name found");
}
method find_lexical_symbol($name) {
my int $i := +@!block_stack;
while $i > 0 {
$i := $i - 1;
my $block := @!block_stack[$i];
my %sym := $block.symbol($name);
return %sym if +%sym;
}
nqp::die("Optimizer: No lexical $name found");
}
# Checks if a given lexical is declared, though it needn't have a compile
# time known value.
method is_lexical_declared($name) {
my int $i := +@!block_stack;
while $i > 0 {
$i := $i - 1;
my $block := @!block_stack[$i];
my %sym := $block.symbol($name);
if +%sym {
return 1;
}
}
0
}
# Forces a value to be made available.
method force_value(%sym, $key, int $die) {
if nqp::existskey(%sym, 'value') {
%sym<value>
}
elsif nqp::existskey(%sym, 'lazy_value_from') {
%sym<value> := nqp::atkey(nqp::atkey(%sym, 'lazy_value_from'), $key)
}
else {
$die ?? nqp::die("No compile-time value for $key") !! NQPMu
}
}
# Works out how many scopes in from the outermost a given name is. A 0
# from this means the nearest declaration is from the setting; a 1 means
# it is in the mainline, etc.
method scopes_in($name) {
my int $i := +@!block_stack;
while $i > 0 {
$i := $i - 1;
my $block := @!block_stack[$i];
my %sym := $block.symbol($name);
if +%sym {
return $i;
}
}
nqp::die("Symbol $name not found");
}
method is_from_core($name) {
my int $i := +@!block_stack;
while $i > 0 {
$i := $i - 1;
my $block := @!block_stack[$i];
my %sym := $block.symbol($name);
if +%sym && nqp::existskey(%sym, 'value') {
my %sym := $block.symbol("!CORE_MARKER");
if +%sym {
return 1;
}
return 0;
}
}
return 0;
}
method find_in_setting($symbol) {
if !nqp::defined($!SETTING) {
my int $i := +@!block_stack;
while $i > 0 && !nqp::defined($!SETTING) {
$i := $i - 1;
my $block := @!block_stack[$i];
my %sym := $block.symbol("!CORE_MARKER");
if +%sym {
$!SETTING := $block;
}
}
if !nqp::defined($!SETTING) {
nqp::die("Optimizer couldn't find CORE while looking for $symbol.");
}
} else {
if nqp::existskey(%!SETTING_CACHE, $symbol) {
return %!SETTING_CACHE{$symbol};
}
}
my %sym := $!SETTING.symbol($symbol);
if +%sym {
return %!SETTING_CACHE{$symbol} := self.force_value(%sym, $symbol, 1);
}
nqp::die("Optimizer couldn't find $symbol in SETTING.");
}
}
# Tracks problems (errors and warnings) discovered by the optimizer as it
# does its work.
my class Problems {
# Symbols object.
has $!symbols;
# Things that should be warned about; keys are warnings, value is an array
# of line numbers.
has %!worrying;
# Typed exceptions, these are all deadly currently
has @!exceptions;
method new($symbols) {
my $obj := nqp::create(self);
$obj.BUILD($symbols);
$obj
}
method BUILD($symbols) {
$!symbols := $symbols;
%!worrying := nqp::hash();
@!exceptions := [];
}
method add_exception(@name, $op, *%opts) {
%opts<line> := HLL::Compiler.lineof($op.node.orig, $op.node.from, :cache(1));
%opts<modules> := $*W.p6ize_recursive(@*MODULES);
# get line numbers - we can't use $*W.locprepost here
# because the cursor has .from as .pos
# in contrast to node
my $pos := $op.node.from;
my $orig := $op.node.orig;
my $prestart := $pos - 40;
$prestart := 0 if $prestart < 0;
my $pre := nqp::substr($orig, $prestart, $pos - $prestart);
$pre := subst($pre, /.*\n/, "", :global);
$pre := '<BOL>' if $pre eq '';
my $postchars := $pos + 40 > nqp::chars($orig) ?? nqp::chars($orig) - $pos !! 40;
my $post := nqp::substr($orig, $pos, $postchars);
$post := subst($post, /\n.*/, "", :global);
$post := '<EOL>' if $post eq '';
%opts<pre> := nqp::box_s($pre, $!symbols.find_symbol(['Str']));
%opts<post> := nqp::box_s($post, $!symbols.find_symbol(['Str']));
%opts<is-compile-time> := nqp::p6bool(1);
for %opts -> $p {
if nqp::islist($p.value) {
my @a := [];
for $p.value {
nqp::push(@a, nqp::hllizefor($_, 'perl6'));
}
%opts{$p.key} := nqp::hllizefor(@a, 'perl6');
}
else {
%opts{$p.key} := nqp::hllizefor($p.value, 'perl6');
}
}
my $file := nqp::getlexdyn('$?FILES');
%opts<filename> := nqp::box_s(
(nqp::isnull($file) ?? '<unknown file>' !! $file),
$!symbols.find_symbol(['Str'])
);
my $exsym := $!symbols.find_symbol(@name);
my $x_comp := $!symbols.find_symbol(['X', 'Comp']);
unless nqp::istype($exsym, $x_comp) {
$exsym := $exsym.HOW.mixin($exsym, $x_comp);
}
my $ex := $exsym.new(|%opts);
nqp::push(@!exceptions, $ex);
}
method add_worry($past_node, $message, @extras?) {
self.add_memo($past_node, $message, @extras, :type<worry>);
}
method add_memo($past_node, $message, @extras?, :$type!) {
my $mnode := $past_node.node;
if !nqp::can($mnode,'orig') {
# note("[DISLOCATED MESSAGE] " ~ $message);
return;
}
my $line := HLL::Compiler.lineof($mnode.orig, $mnode.from, :cache(1));
my $key := $message ~ (+@extras ?? "\n" ~ join("\n", @extras) !! "");
my %cont := %!worrying;
unless %cont{$key} {
%cont{$key} := [];
}
%cont{$key}.push($line);
}
method report() {
if +@!exceptions {
if +@!exceptions > 1 {
my $x_comp_group_sym := $!symbols.find_symbol(['X', 'Comp', 'Group']);
my @exs := [];
for @!exceptions {
nqp::push(@exs, $_);
}
my $x_comp_group := $x_comp_group_sym.new(:sorrows(@exs));
$x_comp_group.throw();
}
else {
@!exceptions[0].throw();
}
}
# We didn't die from any Exception, so we print warnings now.
if +%!worrying {
my $err := stderr();
$err.say("WARNINGS for " ~ $*W.current_file ~ ":");
my @fails;
for %!worrying {
$err.print($_.key ~ " (line" ~ (+$_.value == 1 ?? ' ' !! 's ') ~
join(', ', $_.value) ~ ")\n");
}
}
}
}
# Implements analysis related to variable declarations within a block, which
# includes lexical to local handling and deciding when immediate blocks may
# be flattened into their surrounding block.
my class BlockVarOptimizer {
# Hash mapping variable names declared in the block to the QAST::Var
# of its declaration.
has %!decls;
# Usages of variables in this block, or unioned in from an inlined
# immediate block.
has %!usages_flat;
# Usages of variables in this block, or unioned in from a non-inlined
# immediate block or a declaration block.
has %!usages_inner;
# Have we seen this block (or an inner one) making calls?
has int $!calls;
# Usages of getlexouter.
has @!getlexouter_binds;
# Setup and bind (hopefully one each) of %_.
has @!autoslurpy_setups;
has @!autoslurpy_binds;
# The takedispatcher operation.
has $!takedispatcher;
# If lowering is, for some reason, poisoned.
has int $!poisoned;
# If p6bindsig is used.
has int $!uses_bindsig;
method add_decl($var) {
my str $scope := $var.scope;
if $scope eq 'lexical' || $scope eq 'lexicalref' {
%!decls{$var.name} := $var;
}
}
method add_usage($var) {
my str $scope := $var.scope;
if $scope eq 'lexical' || $scope eq 'lexicalref' {
my $name := $var.name;
my @usages := %!usages_flat{$name};
unless @usages {
@usages := [];
%!usages_flat{$name} := @usages;
}
nqp::push(@usages, $var);
}
}
method register_call() { $!calls++; }
method register_getlexouter_bind($node) {
nqp::push(@!getlexouter_binds, $node);
}
method register_autoslurpy_setup($node) {
nqp::push(@!autoslurpy_setups, $node);
}
method register_autoslurpy_bind($node) {
nqp::push(@!autoslurpy_binds, $node);
}
method register_takedispatcher($node) {
$!takedispatcher := $node;
}
method poison_lowering() { $!poisoned := 1; }
method uses_bindsig() { $!uses_bindsig := 1; }
method get_decls() { %!decls }
method get_usages_flat() { %!usages_flat }
method get_usages_inner() { %!usages_inner }
method get_calls() { $!calls }
method is_poisoned() { $!poisoned }
method is_flattenable() {
for %!decls {
my $var := $_.value;
my str $scope := $var.scope;
return 0 if $scope eq 'lexical' || $scope eq 'lexicalref';
return 0 if $var.decl eq 'param';
}
1
}
method incorporate_inner($vars_info, $flattened) {
# We'll exclude anything that the inner or flattened thing has as
# a declaration, since those are its own.
my %decls := $vars_info.get_decls;
# Inner ones always go into our inners set.
add_to_set(%!usages_inner, $vars_info.get_usages_inner, %decls);
# Flat ones depend on if we flattened this block into ourself.
add_to_set($flattened ?? %!usages_flat !! %!usages_inner,
$vars_info.get_usages_flat, %decls);
# Add up call counts.
$!calls := $!calls + $vars_info.get_calls;
sub add_to_set(%set, %to_add, %exclude) {
for %to_add {
my $name := $_.key;
next if nqp::existskey(%exclude, $name);
my @existing := %set{$name};
if @existing {
for $_.value { nqp::push(@existing, $_) }
#nqp::splice(@existing, $_.value, 0, 0);
}
else {
%set{$name} := $_.value;
}
}
}
}
method delete_unused_magicals($block) {
# Magicals are contextual, so if we call anything when we're done for.
return 0 if $!calls || $!poisoned || $!uses_bindsig;
# Otherwise see if there's any we can kill.
my %kill;
if nqp::existskey(%!decls, '$/') {
if !nqp::existskey(%!usages_flat, '$/') && !nqp::existskey(%!usages_inner, '$/') {
%kill<$/> := 1;
nqp::deletekey(%!decls, '$/');
}
}
if nqp::existskey(%!decls, '$!') {
if !nqp::existskey(%!usages_flat, '$!') && !nqp::existskey(%!usages_inner, '$!') {
%kill<$!> := 1;
nqp::deletekey(%!decls, '$!');
}
}
if nqp::existskey(%!decls, '$Β’') {
if !nqp::existskey(%!usages_flat, '$Β’') && !nqp::existskey(%!usages_inner, '$Β’') {
%kill<$Β’> := 1;
nqp::deletekey(%!decls, '$Β’');
}
}
if nqp::existskey(%!decls, '$_') {
my str $decl := %!decls<$_>.decl;
if $decl eq 'var' || $decl eq 'contvar' {
if !nqp::existskey(%!usages_flat, '$_') && !nqp::existskey(%!usages_inner, '$_') {
if !@!getlexouter_binds {
%kill<$_> := 1;
nqp::deletekey(%!decls, '$_');
}
elsif nqp::elems(@!getlexouter_binds) == 1 {
my $glob := @!getlexouter_binds[0];
if $glob[0].name eq '$_' && $glob[1][0].value eq '$_' {
$glob.op('null');
$glob.shift(); $glob.shift();
%kill<$_> := 1;
nqp::deletekey(%!decls, '$_');
}
}
}
}
}
# If we found things to eliminate, do so.
if %kill {
my @setups := @($block[0]);
my int $i := 0;
my int $n := nqp::elems(@setups);
while $i < $n {
my $consider := @setups[$i];
if nqp::istype($consider, QAST::Var) && nqp::existskey(%kill, $consider.name) {
@setups[$i] := $NULL;
}
$i++;
}
}
}
method delete_unused_autoslurpy() {
if !$!poisoned && !$!uses_bindsig && nqp::existskey(%!decls, '%_')
&& nqp::elems(@!autoslurpy_setups) == 1
&& nqp::elems(@!autoslurpy_binds) == 1 {
if !nqp::existskey(%!usages_inner, '%_') && nqp::elems(%!usages_flat<%_>) == 1 {
my $to_null := @!autoslurpy_setups[0];
nqp::shift($to_null) while @($to_null);
$to_null.op('null');
$to_null := @!autoslurpy_binds[0];
nqp::shift($to_null) while @($to_null);
$to_null.op('null');
}
}
}
method simplify_takedispatcher() {
unless $!calls || $!uses_bindsig {
if $!takedispatcher {
$!takedispatcher.op('cleardispatcher');
$!takedispatcher.shift();
}
}
}
method lexical_vars_to_locals($block) {
return 0 if $!poisoned || $!uses_bindsig;
return 0 unless nqp::istype($block[0], QAST::Stmts);
for %!decls {
# We're looking for lexical var decls; these have no magical
# vivification lexical behavior and so are safe to lower.
my $qast := $_.value;
my str $decl := $qast.decl;
next unless $decl eq 'var';
my str $scope := $qast.scope;
next unless $scope eq 'lexical';
# Also ensure not dynamic.
my $dynamic := try nqp::getattr($qast.value, nqp::p6var($qast.value).WHAT, '$!descriptor').dynamic;
next if $dynamic;
# Consider name. Can't lower if it's used by any nested blocks.
my str $name := $_.key;
unless nqp::existskey(%!usages_inner, $name) {
# Lowerable if it's a normal variable.
next if nqp::chars($name) < 1;
unless nqp::iscclass(nqp::const::CCLASS_ALPHABETIC, $name, 0) {
my str $sigil := nqp::substr($name, 0, 1);
next unless $sigil eq '$' || $sigil eq '@' || $sigil eq '%';
next unless nqp::chars($name) >= 2 &&
nqp::iscclass(nqp::const::CCLASS_ALPHABETIC, $name, 1);
}
# Also must not lexicalref it.
my int $ref'd := 0;
if %!usages_flat{$name} {
for %!usages_flat{$name} {
if $_.scope eq 'lexicalref' {
$ref'd := 1;
last;
}
}
}
next if $ref'd;
# Seems good; lower it. Note we need to retain a lexical in
# case of binder failover to generate errors.
my $new_name := $qast.unique('__lowered_lex');
$block[0].unshift(QAST::Var.new( :name($qast.name), :scope('lexical'),
:decl('var'), :returns($qast.returns) ));
$qast.name($new_name);
$qast.scope('local');
if %!usages_flat{$name} {
for %!usages_flat{$name} {
$_.scope('local');
$_.name($new_name);
}
}
}
}
}
}
# Junction optimizer, responsible for flattening away simple junctions.
my class JunctionOptimizer {
# Junctions we can fold, and what short-circuit operator they fold to.
my %foldable_junction := nqp::hash(
'&infix:<|>', '&infix:<||>',
'&infix:<&>', '&infix:<&&>');
# Contexts in which we can fold a junction.
my %foldable_outer := nqp::hash(
'&prefix:<?>', 1, '&prefix:<!>', 1,
'&prefix:<so>', 1, '&prefix:<not>', 1,
'if', 1, 'unless', 1,
'while', 1, 'until', 1);
# The main optimizer.
has $!optimizer;
# Symbols lookup object.
has $!symbols;
# Constructs a new instance of the junction optimizer.
method new($optimizer, $symbols) {
my $obj := nqp::create(self);
$obj.BUILD($optimizer, $symbols);
$obj
}
method BUILD($optimizer, $symbols) {
$!optimizer := $optimizer;
$!symbols := $symbols;
}
# Check if the junction is in a context where we can optimize.
method is_outer_foldable($op) {
if $op.op eq "call" {
if nqp::existskey(%foldable_outer, $op.name) && $!symbols.is_from_core($op.name) {
return 1;
}
} elsif nqp::existskey(%foldable_outer, $op.op) {
return 1;
}
return 0;
}
# Only if a chain operator handles Any, rather than Mu, in its signature
# will autothreading actually happen.
method chain_handles_Any($op) {
my $obj;
my int $found := 0;
try {
$obj := $!symbols.find_lexical($op);
$found := 1;
}
if $found == 1 {
my @candidates;
if $obj.is_dispatcher {
my $Routine := $!symbols.find_in_setting("Routine");
@candidates := nqp::getattr($obj, $Routine, '@!dispatchees');
}
else {
@candidates := nqp::list($obj);
}
my $signature := $!symbols.find_in_setting("Signature");
my $canditer := nqp::iterator(@candidates);
while $canditer {
my $cand := nqp::shift($canditer);
my $iter := nqp::iterator(nqp::getattr($cand.signature, $signature, '@!params'));
while $iter {
my $p := nqp::shift($iter);
unless nqp::istype($p.type, $!symbols.Any) {
return 0;
}
}
}
return 1;
} else {
return 0;
}
return 0;
}
method can_chain_junction_be_warped($node) {
sub has_core-ish_junction($node) {
if nqp::istype($node, QAST::Op) && $node.op eq 'call' &&
nqp::existskey(%foldable_junction, $node.name) {
if $!symbols.is_from_core($node.name) {
# TODO: special handling for any()/all(), because they create
# a Stmts with a infix:<,> in it.
if +$node.list == 1 {
return 0;
}
return 1;
}
}
return 0;
}
if has_core-ish_junction($node[0]) {
return 0;
} elsif has_core-ish_junction($node[1]) {
return 1;
}
return -1;
}
method optimize($op) {
if self.is_outer_foldable($op) && nqp::istype($op[0], QAST::Op) {
my $proceed := 0;
my $exp-side;
if $op[0].op eq "chain" {
$exp-side := self.can_chain_junction_be_warped($op[0]);
$proceed := $exp-side != -1 && self.chain_handles_Any($op[0].name) == 1
} elsif $op[0].op eq 'callmethod' && $op[0].name eq 'ACCEPTS' {
$exp-side := self.can_chain_junction_be_warped($op[0]);
# we should only ever find the 0nd child (the invocant) to be a junction anyway.
$proceed := $exp-side == 0;
}
if $proceed {
return self.apply_transform($op, $exp-side);
}
}
return NQPMu;
}
method apply_transform($op, $exp-side) {
# TODO chain_handles_Any may get more cleverness to check only the parameters that actually have
# a junction passed to them, so that in some cases the unfolding may still happen.
my str $juncop := $op[0][$exp-side].name eq '&infix:<&>' ?? 'if' !! 'unless';
my str $juncname := %foldable_junction{$op[0][$exp-side].name};
my str $chainop := $op[0].op;
my str $chainname := $op[0].name;
my $values := $op[0][$exp-side];
my $ovalue := $op[0][1 - $exp-side];
# the first time $valop is refered to, create a bind op for a
# local var, next time create a reference var op.
my %reference;
sub refer_to($valop) {
my $id := nqp::where($valop);
if nqp::existskey(%reference, $id) {
QAST::Var.new(:name(%reference{$id}), :scope<local>);
} else {
%reference{$id} := $op.unique('junction_unfold');
QAST::Op.new(:op<bind>,
QAST::Var.new(:name(%reference{$id}),
:scope<local>,
:decl<var>),
$valop);
}
}
# create a comparison operation for the inner comparisons
sub chain($value) {
if $exp-side == 0 {
QAST::Op.new(:op($chainop), :name($chainname),
$value,
refer_to($ovalue));
} else {
QAST::Op.new(:op($chainop), :name($chainname),
refer_to($ovalue),
$value);
}
}
# create a chain of outer logical junction operators with inner comparisons
sub create_junc() {
my $junc := QAST::Op.new(:name($juncname), :op($juncop));
$junc.push(chain($values.shift()));
if +$values.list > 1 {
$junc.push(create_junc());
} else {
$junc.push(chain($values.shift()));
}
return $junc;
}
$op.shift;
$op.unshift(create_junc());
return $!optimizer.visit_op($op);
}
}
# Drives the optimization process overall.
class Perl6::Optimizer {
# Symbols tracking object.
has $!symbols;
# Stack of block variable optimizers.
has @!block_var_stack;
# Junction optimizer.
has $!junc_opt;
# Track problems we encounter.
has $!problems;
# Optimizer configuration.
has %!adverbs;
# The optimization level.
has $!level;
# How deep a chain we're in, for chaining operators.
has int $!chain_depth;
# Are we in void context?
has int $!void_context;
# Are we in a declaration?
has int $!in_declaration;
# one shared QAST tree we'll put into every block we've eliminated
has $!eliminated_block_contents;
has $!debug;
# Entry point for the optimization process.
method optimize($past, *%adverbs) {
# Initialize.
$!symbols := Symbols.new($past);
@!block_var_stack := [];
$!junc_opt := JunctionOptimizer.new(self, $!symbols);
$!problems := Problems.new($!symbols);
$!chain_depth := 0;
$!in_declaration := 0;
$!void_context := 0;
$!debug := nqp::getenvhash<RAKUDO_OPTIMIZER_DEBUG>;
my $*DYNAMICALLY_COMPILED := 0;
my $*W := $past.ann('W');
# Work out optimization level.
$!level := nqp::existskey(%adverbs, 'optimize') ??
+%adverbs<optimize> !! 2;
%!adverbs := %adverbs;
note("method optimize before\n" ~ $past.dump) if $!debug;
$!eliminated_block_contents := QAST::Op.new( :op('die_s'),
QAST::SVal.new( :value('INTERNAL ERROR: Execution of block eliminated by optimizer') ) );
# Walk and optimize the program.
self.visit_block($!symbols.UNIT);
# Report any discovered problems.
$!problems.report();
note("method optimize after\n" ~ $past.dump) if $!debug;
$past
}
# Called when we encounter a block in the tree.
method visit_block($block) {
# Push block onto block stack and create vars tracking.
$!symbols.push_block($block);
@!block_var_stack.push(BlockVarOptimizer.new);
# we don't want any "blah in sink context" warnings emitted here
get_last_stmt($block[1]).annotate: 'sink-quietly', 1
if $block.ann: 'WANTMEPLEASE';
# Visit children.
if $block.ann('DYNAMICALLY_COMPILED') {
my $*DYNAMICALLY_COMPILED := 1;
self.visit_children($block, :resultchild(+@($block) - 1),:void_default);
}
else {
self.visit_children($block, :resultchild(+@($block) - 1),:void_default);
}
# Pop block from block stack and get computed block var info.
$!symbols.pop_block();
my $vars_info := @!block_var_stack.pop();
# If this block is UNIT and we're in interactive mode, poison lexical
# to local lowering, or else we may lose symbols we need to remember.
if $block =:= $!symbols.UNIT && %!adverbs<interactive> {
$vars_info.poison_lowering();
}
# We might be able to delete some of the magical variables when they
# are trivially unused, and also simplify takedispatcher.
if $!level >= 1 {
$vars_info.delete_unused_magicals($block);
$vars_info.delete_unused_autoslurpy();
$vars_info.simplify_takedispatcher();
}
# If the block is immediate, we may be able to inline it.
my int $flattened := 0;
my $result := $block;
if $block.blocktype eq 'immediate' && $block.arity == 0
&& !$vars_info.is_poisoned && !$block.has_exit_handler {
# Scan symbols for any non-interesting ones.
my @sigsyms;
for $block.symtable() {
my $name := $_.key;
if $name ne '$_' && $name ne '$*DISPATCHER' {
@sigsyms.push($name);
}
}
# If we dynamically compiled it, then it must not contain
# any nested blocks.
if $*DYNAMICALLY_COMPILED {
for $block[0].list {
if nqp::istype($_, QAST::Block) && $_.blocktype ne 'raw' {
@sigsyms.push('');
}
}
}
# If we have no interesting ones, then we can inline the
# statements.
if +@sigsyms == 0 {
if $!level >= 2 {
my $outer := $!symbols.top_block;
$result := self.inline_immediate_block($block, $outer,
nqp::existskey($vars_info.get_decls(), '$_'));
}
}
}
# Do any possible lexical => local lowering.