summaryrefslogtreecommitdiff
path: root/node.c
blob: 14f9856ba5611ef9340f56f2218ee5f7520bae1f (plain)
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
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
/**********************************************************************

  node.c - ruby node tree

  $Author: mame $
  created at: 09/12/06 21:23:44 JST

  Copyright (C) 2009 Yusuke Endoh

**********************************************************************/

#include "ruby/ruby.h"
#include "vm_core.h"

#define A(str) rb_str_cat2(buf, (str))
#define AR(str) rb_str_concat(buf, (str))

#define A_INDENT add_indent(buf, indent)
#define A_ID(id) add_id(buf, (id))
#define A_INT(val) rb_str_catf(buf, "%d", (val))
#define A_LONG(val) rb_str_catf(buf, "%ld", (val))
#define A_LIT(lit) AR(rb_inspect(lit))
#define A_NODE_HEADER(node, term) \
    rb_str_catf(buf, "@ %s (line: %d)"term, ruby_node_name(nd_type(node)), nd_line(node))
#define A_FIELD_HEADER(len, name, term) \
    rb_str_catf(buf, "+- %.*s:"term, (len), (name))
#define D_FIELD_HEADER(len, name, term) (A_INDENT, A_FIELD_HEADER(len, name, term))

#define D_NULL_NODE (A_INDENT, A("(null node)\n"))
#define D_NODE_HEADER(node) (A_INDENT, A_NODE_HEADER(node, "\n"))

#define COMPOUND_FIELD(len, name, block) \
    do { \
	D_FIELD_HEADER((len), (name), "\n");	\
	rb_str_cat2(indent, next_indent); \
	block; \
	rb_str_resize(indent, RSTRING_LEN(indent) - 4); \
    } while (0)

#define COMPOUND_FIELD1(name, ann, block) \
    COMPOUND_FIELD(FIELD_NAME_LEN(name, ann), \
		   FIELD_NAME_DESC(name, ann), \
		   block)

#define FIELD_NAME_DESC(name, ann) name " (" ann ")"
#define FIELD_NAME_LEN(name, ann) (int)( \
	comment ? \
	rb_strlen_lit(FIELD_NAME_DESC(name, ann)) : \
	rb_strlen_lit(name))
#define SIMPLE_FIELD(len, name) \
    for (D_FIELD_HEADER((len), (name), " "), field_flag = 1; \
	 field_flag; /* should be optimized away */ \
	 A("\n"), field_flag = 0)

#define SIMPLE_FIELD1(name, ann)    SIMPLE_FIELD(FIELD_NAME_LEN(name, ann), FIELD_NAME_DESC(name, ann))
#define F_CUSTOM1(name, ann)	    SIMPLE_FIELD1(#name, ann)
#define F_ID(name, ann) 	    SIMPLE_FIELD1(#name, ann) A_ID(node->name)
#define F_GENTRY(name, ann)	    SIMPLE_FIELD1(#name, ann) A_ID((node->name)->id)
#define F_INT(name, ann)	    SIMPLE_FIELD1(#name, ann) A_INT(node->name)
#define F_LONG(name, ann)	    SIMPLE_FIELD1(#name, ann) A_LONG(node->name)
#define F_LIT(name, ann)	    SIMPLE_FIELD1(#name, ann) A_LIT(node->name)
#define F_MSG(name, ann, desc)	    SIMPLE_FIELD1(#name, ann) A(desc)

#define F_NODE(name, ann) \
    COMPOUND_FIELD1(#name, ann, dump_node(buf, indent, comment, node->name))
#define F_OPTION(name, ann) \
    COMPOUND_FIELD1(#name, ann, dump_option(buf, indent, node->name))

#define ANN(ann) \
    if (comment) { \
	A_INDENT; A("| # " ann "\n"); \
    }

#define LAST_NODE (next_indent = "    ")

static void
add_indent(VALUE buf, VALUE indent)
{
    AR(indent);
}

static void
add_id(VALUE buf, ID id)
{
    if (id == 0) {
	A("(null)");
    }
    else {
	VALUE str = rb_id2str(id);
	if (str) {
	    A(":"); AR(str);
	}
	else {
	    A("(internal variable)");
	}
    }
}

struct add_option_arg {
    VALUE buf, indent;
    st_index_t count;
};

static int
add_option_i(VALUE key, VALUE val, VALUE args)
{
    struct add_option_arg *argp = (void *)args;
    VALUE buf = argp->buf;
    VALUE indent = argp->indent;

    A_INDENT;
    A("+- ");
    AR(rb_sym2str(key));
    A(": ");
    A_LIT(val);
    A("\n");
    return ST_CONTINUE;
}

static void
dump_option(VALUE buf, VALUE indent, VALUE opt)
{
    struct add_option_arg arg;

    if (!RB_TYPE_P(opt, T_HASH)) {
	A_LIT(opt);
	return;
    }
    arg.buf = buf;
    arg.indent = indent;
    arg.count = 0;
    rb_hash_foreach(opt, add_option_i, (VALUE)&arg);
}

static void dump_node(VALUE, VALUE, int, NODE *);
static const char default_indent[] = "|   ";

static void
dump_array(VALUE buf, VALUE indent, int comment, NODE *node)
{
    int field_flag;
    const char *next_indent = default_indent;
    D_NODE_HEADER(node);
    F_LONG(nd_alen, "length");
    F_NODE(nd_head, "element");
    while (node->nd_next && nd_type(node->nd_next) == NODE_ARRAY) {
	node = node->nd_next;
	F_NODE(nd_head, "element");
    }
    LAST_NODE;
    F_NODE(nd_next, "next element");
}

static void
dump_node(VALUE buf, VALUE indent, int comment, NODE *node)
{
    int field_flag;
    const char *next_indent = default_indent;

    if (!node) {
	D_NULL_NODE;
	return;
    }

    D_NODE_HEADER(node);

    switch (nd_type(node)) {
      case NODE_BLOCK:
	ANN("statement sequence");
	ANN("format: [nd_head]; [nd_next]");
	ANN("example: foo; bar");
	F_NODE(nd_head, "current statement");
	LAST_NODE;
	F_NODE(nd_next, "next block");
	break;

      case NODE_IF:
	ANN("if statement");
	ANN("format: if [nd_cond] then [nd_body] else [nd_else] end");
	ANN("example: if x == 1 then foo else bar end");
	F_NODE(nd_cond, "condition expr");
	F_NODE(nd_body, "then clause");
	LAST_NODE;
	F_NODE(nd_else, "else clause");
	break;

      case NODE_CASE:
	ANN("case statement");
	ANN("format: case [nd_head]; [nd_body]; end");
	ANN("example: case x; when 1; foo; when 2; bar; else baz; end");
	F_NODE(nd_head, "case expr");
	LAST_NODE;
	F_NODE(nd_body, "when clauses");
	break;

      case NODE_WHEN:
	ANN("if statement");
	ANN("format: when [nd_head]; [nd_body]; (when or else) [nd_next]");
	ANN("example: case x; when 1; foo; when 2; bar; else baz; end");
	F_NODE(nd_head, "when value");
	F_NODE(nd_body, "when clause");
	LAST_NODE;
	F_NODE(nd_next, "next when clause");
	break;

      case NODE_OPT_N:
	ANN("wrapper for -n option");
	ANN("format: ruby -ne '[nd_body]' (nd_cond is `gets')");
	ANN("example: ruby -ne 'p $_'");
	goto loop;
      case NODE_WHILE:
	ANN("while statement");
	ANN("format: while [nd_cond]; [nd_body]; end");
	ANN("example: while x == 1; foo; end");
	goto loop;
      case NODE_UNTIL:
	ANN("until statement");
	ANN("format: until [nd_cond]; [nd_body]; end");
	ANN("example: until x == 1; foo; end");
      loop:
	F_CUSTOM1(nd_state, "begin-end-while?") {
	    A_INT((int)node->nd_state);
	    A((node->nd_state == 1) ? " (while-end)" : " (begin-end-while)");
	}
	F_NODE(nd_cond, "condition");
	LAST_NODE;
	F_NODE(nd_body, "body");
	break;

      case NODE_ITER:
	ANN("method call with block");
	ANN("format: [nd_iter] { [nd_body] }");
	ANN("example: 3.times { foo }");
	goto iter;
      case NODE_FOR:
	ANN("for statement");
	ANN("format: for * in [nd_iter] do [nd_body] end");
	ANN("example: for i in 1..3 do foo end");
      iter:
	F_NODE(nd_iter, "iteration receiver");
	LAST_NODE;
	F_NODE(nd_body, "body");
	break;

      case NODE_BREAK:
	ANN("for statement");
	ANN("format: break [nd_stts]");
	ANN("example: break 1");
	goto jump;
      case NODE_NEXT:
	ANN("next statement");
	ANN("format: next [nd_stts]");
	ANN("example: next 1");
	goto jump;
      case NODE_RETURN:
	ANN("return statement");
	ANN("format: return [nd_stts]");
	ANN("example: return 1");
      jump:
	LAST_NODE;
	F_NODE(nd_stts, "value");
	break;

      case NODE_REDO:
	ANN("redo statement");
	ANN("format: redo");
	ANN("example: redo");
	break;

      case NODE_RETRY:
	ANN("retry statement");
	ANN("format: retry");
	ANN("example: retry");
	break;

      case NODE_BEGIN:
	ANN("begin statement");
	ANN("format: begin; [nd_body]; end");
	ANN("example: begin; 1; end");
	LAST_NODE;
	F_NODE(nd_body, "body");
	break;

      case NODE_RESCUE:
	ANN("rescue clause");
	ANN("format: begin; [nd_body]; (rescue) [nd_resq]; else [nd_else]; end");
	ANN("example: begin; foo; rescue; bar; else; baz; end");
	F_NODE(nd_head, "body");
	F_NODE(nd_resq, "rescue clause list");
	LAST_NODE;
	F_NODE(nd_else, "rescue else clause");
	break;

      case NODE_RESBODY:
	ANN("rescue clause (cont'd)");
	ANN("format: rescue [nd_args]; [nd_body]; (rescue) [nd_head]");
	ANN("example: begin; foo; rescue; bar; else; baz; end");
	F_NODE(nd_args, "rescue exceptions");
	F_NODE(nd_body, "rescue clause");
	LAST_NODE;
	F_NODE(nd_head, "next rescue clause");
	break;

      case NODE_ENSURE:
	ANN("ensure clause");
	ANN("format: begin; [nd_head]; ensure; [nd_ensr]; end");
	ANN("example: begin; foo; ensure; bar; end");
	F_NODE(nd_head, "body");
	LAST_NODE;
	F_NODE(nd_ensr, "ensure clause");
	break;

      case NODE_AND:
	ANN("&& operator");
	ANN("format: [nd_1st] && [nd_2nd]");
	ANN("example: foo && bar");
	goto andor;
      case NODE_OR:
	ANN("|| operator");
	ANN("format: [nd_1st] || [nd_2nd]");
	ANN("example: foo && bar");
      andor:
	F_NODE(nd_1st, "left expr");
	LAST_NODE;
	F_NODE(nd_2nd, "right expr");
	break;

      case NODE_MASGN:
	ANN("multiple assignment");
	ANN("format: [nd_head], [nd_args] = [nd_value]");
	ANN("example: a, b = foo");
	F_NODE(nd_value, "rhsn");
	F_NODE(nd_head, "lhsn");
	if ((VALUE)node->nd_args != (VALUE)-1) {
	    LAST_NODE;
	    F_NODE(nd_args, "splatn");
	}
	else {
	    F_MSG(nd_args, "splatn", "-1 (rest argument without name)");
	}
	break;

      case NODE_LASGN:
	ANN("local variable assignment");
	ANN("format: [nd_vid](lvar) = [nd_value]");
	ANN("example: x = foo");
	goto asgn;
      case NODE_DASGN:
	ANN("dynamic variable assignment (out of current scope)");
	ANN("format: [nd_vid](dvar) = [nd_value]");
	ANN("example: x = nil; 1.times { x = foo }");
	goto asgn;
      case NODE_DASGN_CURR:
	ANN("dynamic variable assignment (in current scope)");
	ANN("format: [nd_vid](current dvar) = [nd_value]");
	ANN("example: 1.times { x = foo }");
	goto asgn;
      case NODE_IASGN:
	ANN("instance variable assignment");
	ANN("format: [nd_vid](ivar) = [nd_value]");
	ANN("example: @x = foo");
	goto asgn;
      case NODE_CVASGN:
	ANN("class variable assignment");
	ANN("format: [nd_vid](cvar) = [nd_value]");
	ANN("example: @@x = foo");
      asgn:
	F_ID(nd_vid, "variable");
	LAST_NODE;
	if (node->nd_value == (NODE *)-1) {
	    F_MSG(nd_value, "rvalue", "(required keyword argument)");
	}
	else {
	    F_NODE(nd_value, "rvalue");
	}
	break;

      case NODE_GASGN:
	ANN("global variable assignment");
	ANN("format: [nd_entry](gvar) = [nd_value]");
	ANN("example: $x = foo");
	F_GENTRY(nd_entry, "global variable");
	LAST_NODE;
	F_NODE(nd_value, "rvalue");
	break;

      case NODE_CDECL:
	ANN("constant declaration");
	ANN("format: [nd_else]::[nd_vid](constant) = [nd_value]");
	ANN("example: X = foo");
	if (node->nd_vid) {
	   F_ID(nd_vid, "variable");
	   F_MSG(nd_else, "extension", "not used");
	}
	else {
	   F_MSG(nd_vid, "variable", "0 (see extension field)");
	   F_NODE(nd_else, "extension");
	}
	LAST_NODE;
	F_NODE(nd_value, "rvalue");
	break;

      case NODE_OP_ASGN1:
	ANN("array assignment with operator");
	ANN("format: [nd_value] [ [nd_args->nd_body] ] [nd_vid]= [nd_args->nd_head]");
	ANN("example: ary[1] += foo");
	F_NODE(nd_recv, "receiver");
	F_ID(nd_vid, "operator");
	F_NODE(nd_args->nd_body, "index");
	LAST_NODE;
	F_NODE(nd_args->nd_head, "rvalue");
	break;

      case NODE_OP_ASGN2:
	ANN("attr assignment with operator");
	ANN("format: [nd_value].[attr] [nd_next->nd_mid]= [nd_value]");
	ANN("          where [attr]: [nd_next->nd_vid]");
	ANN("example: struct.field += foo");
	F_NODE(nd_recv, "receiver");
	F_CUSTOM1(nd_next->nd_vid, "attr") {
	    if (node->nd_next->nd_aid) A("? ");
	    A_ID(node->nd_next->nd_vid);
	}
	F_CUSTOM1(nd_next->nd_mid, "operator") {
	    switch (node->nd_next->nd_mid) {
	      case 0: A("0 (||)"); break;
	      case 1: A("1 (&&)"); break;
	      default: A_ID(node->nd_next->nd_mid);
	    }
	}
	LAST_NODE;
	F_NODE(nd_value, "rvalue");
	break;

      case NODE_OP_ASGN_AND:
	ANN("assignment with && operator");
	ANN("format: [nd_head] &&= [nd_value]");
	ANN("example: foo &&= bar");
	goto asgn_andor;
      case NODE_OP_ASGN_OR:
	ANN("assignment with || operator");
	ANN("format: [nd_head] ||= [nd_value]");
	ANN("example: foo ||= bar");
      asgn_andor:
	F_NODE(nd_head, "variable");
	LAST_NODE;
	F_NODE(nd_value, "rvalue");
	break;

      case NODE_CALL:
	ANN("method invocation");
	ANN("format: [nd_recv].[nd_mid]([nd_args])");
	ANN("example: obj.foo(1)");
	F_ID(nd_mid, "method id");
	F_NODE(nd_recv, "receiver");
	LAST_NODE;
	F_NODE(nd_args, "arguments");
	break;

      case NODE_FCALL:
	ANN("function call");
	ANN("format: [nd_mid]([nd_args])");
	ANN("example: foo(1)");
	F_ID(nd_mid, "method id");
	LAST_NODE;
	F_NODE(nd_args, "arguments");
	break;

      case NODE_VCALL:
	ANN("function call with no argument");
	ANN("format: [nd_mid]");
	ANN("example: foo");
	F_ID(nd_mid, "method id");
	break;

      case NODE_QCALL:
	ANN("safe method invocation");
	ANN("format: [nd_recv]&.[nd_mid]([nd_args])");
	ANN("example: obj&.foo(1)");
	F_ID(nd_mid, "method id");
	F_NODE(nd_recv, "receiver");
	LAST_NODE;
	F_NODE(nd_args, "arguments");
	break;

      case NODE_SUPER:
	ANN("super invocation");
	ANN("format: super [nd_args]");
	ANN("example: super 1");
	LAST_NODE;
	F_NODE(nd_args, "arguments");
	break;

      case NODE_ZSUPER:
	ANN("super invocation with no argument");
	ANN("format: super");
	ANN("example: super");
	break;

      case NODE_ARRAY:
	ANN("array constructor");
	ANN("format: [ [nd_head], [nd_next].. ] (length: [nd_alen])");
	ANN("example: [1, 2, 3]");
	goto ary;
      case NODE_VALUES:
	ANN("return arguments");
	ANN("format: [ [nd_head], [nd_next].. ] (length: [nd_alen])");
	ANN("example: return 1, 2, 3");
      ary:
	dump_array(buf, indent, comment, node);
	break;

      case NODE_ZARRAY:
	ANN("empty array constructor");
	ANN("format: []");
	ANN("example: []");
	break;

      case NODE_HASH:
	ANN("hash constructor");
	ANN("format: { [nd_head] }");
	ANN("example: { 1 => 2, 3 => 4 }");
	LAST_NODE;
	F_NODE(nd_head, "contents");
	break;

      case NODE_YIELD:
	ANN("yield invocation");
	ANN("format: yield [nd_head]");
	ANN("example: yield 1");
	LAST_NODE;
	F_NODE(nd_head, "arguments");
	break;

      case NODE_LVAR:
	ANN("local variable reference");
	ANN("format: [nd_vid](lvar)");
	ANN("example: x");
	goto var;
      case NODE_DVAR:
	ANN("dynamic variable reference");
	ANN("format: [nd_vid](dvar)");
	ANN("example: 1.times { x = 1; x }");
	goto var;
      case NODE_IVAR:
	ANN("instance variable reference");
	ANN("format: [nd_vid](ivar)");
	ANN("example: @x");
	goto var;
      case NODE_CONST:
	ANN("constant reference");
	ANN("format: [nd_vid](constant)");
	ANN("example: X");
	goto var;
      case NODE_CVAR:
	ANN("class variable reference");
	ANN("format: [nd_vid](cvar)");
	ANN("example: @@x");
      var:
	F_ID(nd_vid, "local variable");
	break;

      case NODE_GVAR:
	ANN("global variable reference");
	ANN("format: [nd_entry](gvar)");
	ANN("example: $x");
	F_GENTRY(nd_entry, "global variable");
	break;

      case NODE_NTH_REF:
	ANN("nth special variable reference");
	ANN("format: $[nd_nth]");
	ANN("example: $1, $2, ..");
	F_CUSTOM1(nd_nth, "variable") { A("$"); A_LONG(node->nd_nth); }
	break;

      case NODE_BACK_REF:
	ANN("back special variable reference");
	ANN("format: $[nd_nth]");
	ANN("example: $&, $`, $', $+");
	F_CUSTOM1(nd_nth, "variable") {
	    char name[3];
	    name[0] = '$';
	    name[1] = (char)node->nd_nth;
	    name[2] = '\0';
	    A(name);
	}
	break;

      case NODE_MATCH:
	ANN("match expression (against $_ implicitly)");
        ANN("format: [nd_lit] (in condition)");
	ANN("example: if /foo/; foo; end");
	F_LIT(nd_lit, "regexp");
	break;

      case NODE_MATCH2:
	ANN("match expression (regexp first)");
        ANN("format: [nd_recv] =~ [nd_value]");
	ANN("example: /foo/ =~ 'foo'");
	F_NODE(nd_recv, "regexp (receiver)");
	if (!node->nd_args) LAST_NODE;
	F_NODE(nd_value, "string (argument)");
	if (node->nd_args) {
	    LAST_NODE;
	    F_NODE(nd_args, "named captures");
	}
	break;

      case NODE_MATCH3:
	ANN("match expression (regexp second)");
        ANN("format: [nd_recv] =~ [nd_value]");
	ANN("example: 'foo' =~ /foo/");
	F_NODE(nd_recv, "string (receiver)");
	LAST_NODE;
	F_NODE(nd_value, "regexp (argument)");
	break;

      case NODE_LIT:
	ANN("literal");
	ANN("format: [nd_lit]");
	ANN("example: 1, /foo/");
	goto lit;
      case NODE_STR:
	ANN("string literal");
	ANN("format: [nd_lit]");
	ANN("example: 'foo'");
	goto lit;
      case NODE_XSTR:
	ANN("xstring literal");
	ANN("format: [nd_lit]");
	ANN("example: `foo`");
      lit:
	F_LIT(nd_lit, "literal");
	break;

      case NODE_DSTR:
	ANN("string literal with interpolation");
	ANN("format: [nd_lit]");
	ANN("example: \"foo#{ bar }baz\"");
	goto dlit;
      case NODE_DXSTR:
	ANN("xstring literal with interpolation");
	ANN("format: [nd_lit]");
	ANN("example: `foo#{ bar }baz`");
	goto dlit;
      case NODE_DREGX:
	ANN("regexp literal with interpolation");
	ANN("format: [nd_lit]");
	ANN("example: /foo#{ bar }baz/");
	goto dlit;
      case NODE_DREGX_ONCE:
	ANN("regexp literal with interpolation and once flag");
	ANN("format: [nd_lit]");
	ANN("example: /foo#{ bar }baz/o");
	goto dlit;
      case NODE_DSYM:
	ANN("symbol literal with interpolation");
	ANN("format: [nd_lit]");
	ANN("example: :\"foo#{ bar }baz\"");
      dlit:
	F_LIT(nd_lit, "preceding string");
	F_NODE(nd_next->nd_head, "interpolation");
	LAST_NODE;
	F_NODE(nd_next->nd_next, "tailing strings");
	break;

      case NODE_EVSTR:
	ANN("interpolation expression");
	ANN("format: \"..#{ [nd_lit] }..\"");
	ANN("example: \"foo#{ bar }baz\"");
	LAST_NODE;
	F_NODE(nd_body, "body");
	break;

      case NODE_ARGSCAT:
	ANN("splat argument following arguments");
	ANN("format: ..(*[nd_head], [nd_body..])");
	ANN("example: foo(*ary, post_arg1, post_arg2)");
	F_NODE(nd_head, "preceding array");
	LAST_NODE;
	F_NODE(nd_body, "following array");
	break;

      case NODE_ARGSPUSH:
	ANN("splat argument following one argument");
	ANN("format: ..(*[nd_head], [nd_body])");
	ANN("example: foo(*ary, post_arg)");
	F_NODE(nd_head, "preceding array");
	LAST_NODE;
	F_NODE(nd_body, "following element");
	break;

      case NODE_SPLAT:
	ANN("splat argument");
	ANN("format: *[nd_head]");
	ANN("example: foo(*ary)");
	LAST_NODE;
	F_NODE(nd_head, "splat'ed array");
	break;

      case NODE_BLOCK_PASS:
	ANN("arguments with block argument");
	ANN("format: ..([nd_head], &[nd_body])");
	ANN("example: foo(x, &blk)");
	F_NODE(nd_head, "other arguments");
	LAST_NODE;
	F_NODE(nd_body, "block argument");
	break;

      case NODE_DEFN:
	ANN("method definition");
	ANN("format: def [nd_mid] [nd_defn]; end");
	ANN("example; def foo; bar; end");
	F_ID(nd_mid, "method name");
	LAST_NODE;
	F_NODE(nd_defn, "method definition");
	break;

      case NODE_DEFS:
	ANN("singleton method definition");
	ANN("format: def [nd_recv].[nd_mid] [nd_defn]; end");
	ANN("example; def obj.foo; bar; end");
	F_NODE(nd_recv, "receiver");
	F_ID(nd_mid, "method name");
	LAST_NODE;
	F_NODE(nd_defn, "method definition");
	break;

      case NODE_ALIAS:
	ANN("method alias statement");
	ANN("format: alias [u1.node] [u2.node]");
	ANN("example: alias bar foo");
	F_NODE(u1.node, "new name");
	LAST_NODE;
	F_NODE(u2.node, "old name");
	break;

      case NODE_VALIAS:
	ANN("global variable alias statement");
	ANN("format: alias [u1.id](gvar) [u2.id](gvar)");
	ANN("example: alias $y $x");
	F_ID(u1.id, "new name");
	F_ID(u2.id, "old name");
	break;

      case NODE_UNDEF:
	ANN("method alias statement");
	ANN("format: undef [u2.node]");
	ANN("example: undef foo");
	LAST_NODE;
	F_NODE(u2.node, "old name");
	break;

      case NODE_CLASS:
	ANN("class definition");
	ANN("format: class [nd_cpath] < [nd_super]; [nd_body]; end");
	ANN("example: class C2 < C; ..; end");
	F_NODE(nd_cpath, "class path");
	F_NODE(nd_super, "superclass");
	LAST_NODE;
	F_NODE(nd_body, "class definition");
	break;

      case NODE_MODULE:
	ANN("module definition");
	ANN("format: module [nd_cpath]; [nd_body]; end");
	ANN("example: module M; ..; end");
	F_NODE(nd_cpath, "module path");
	LAST_NODE;
	F_NODE(nd_body, "module definition");
	break;

      case NODE_SCLASS:
	ANN("singleton class definition");
	ANN("format: class << [nd_recv]; [nd_body]; end");
	ANN("example: class << obj; ..; end");
	F_NODE(nd_recv, "receiver");
	LAST_NODE;
	F_NODE(nd_body, "singleton class definition");
	break;

      case NODE_COLON2:
	ANN("scoped constant reference");
	ANN("format: [nd_head]::[nd_mid]");
	ANN("example: M::C");
	F_ID(nd_mid, "constant name");
	LAST_NODE;
	F_NODE(nd_head, "receiver");
	break;

      case NODE_COLON3:
	ANN("top-level constant reference");
	ANN("format: ::[nd_mid]");
	ANN("example: ::Object");
	F_ID(nd_mid, "constant name");
	break;

      case NODE_DOT2:
	ANN("range constructor (incl.)");
	ANN("format: [nd_beg]..[nd_end]");
	ANN("example: 1..5");
	goto dot;
      case NODE_DOT3:
	ANN("range constructor (excl.)");
	ANN("format: [nd_beg]...[nd_end]");
	ANN("example: 1...5");
	goto dot;
      case NODE_FLIP2:
	ANN("flip-flop condition (incl.)");
	ANN("format: [nd_beg]..[nd_end]");
	ANN("example: if (x==1)..(x==5); foo; end");
	goto dot;
      case NODE_FLIP3:
	ANN("flip-flop condition (excl.)");
	ANN("format: [nd_beg]...[nd_end]");
	ANN("example: if (x==1)...(x==5); foo; end");
      dot:
	F_NODE(nd_beg, "begin");
	LAST_NODE;
	F_NODE(nd_end, "end");
	break;

      case NODE_SELF:
	ANN("self");
	ANN("format: self");
	ANN("example: self");
	break;

      case NODE_NIL:
	ANN("nil");
	ANN("format: nil");
	ANN("example: nil");
	break;

      case NODE_TRUE:
	ANN("true");
	ANN("format: true");
	ANN("example: true");
	break;

      case NODE_FALSE:
	ANN("false");
	ANN("format: false");
	ANN("example: false");
	break;

      case NODE_ERRINFO:
	ANN("virtual reference to $!");
	ANN("format: rescue => id");
	ANN("example: rescue => id");
	break;

      case NODE_DEFINED:
	ANN("defined? expression");
	ANN("format: defined?([nd_head])");
	ANN("example: defined?(foo)");
	F_NODE(nd_head, "expr");
	break;

      case NODE_POSTEXE:
	ANN("post-execution");
	ANN("format: END { [nd_body] }");
	ANN("example: END { foo }");
	LAST_NODE;
	F_NODE(nd_body, "END clause");
	break;

      case NODE_ATTRASGN:
	ANN("attr assignment");
	ANN("format: [nd_recv].[nd_mid] = [nd_args]");
	ANN("example: struct.field = foo");
	if (node->nd_recv == (NODE *) 1) {
	    F_MSG(nd_recv, "receiver", "1 (self)");
	}
	else {
	    F_NODE(nd_recv, "receiver");
	}
	F_ID(nd_mid, "method name");
	LAST_NODE;
	F_NODE(nd_args, "arguments");
	break;

      case NODE_PRELUDE:
	ANN("pre-execution");
	ANN("format: BEGIN { [nd_head] }; [nd_body]");
	ANN("example: bar; BEGIN { foo }");
#define nd_compile_option u3.value
	F_NODE(nd_head, "prelude");
	if (!node->nd_compile_option) LAST_NODE;
	F_NODE(nd_body, "body");
	if (node->nd_compile_option) {
	    LAST_NODE;
	    F_OPTION(nd_compile_option, "compile_option");
	}
	break;

      case NODE_LAMBDA:
	ANN("lambda expression");
	ANN("format: -> [nd_body]");
	ANN("example: -> { foo }");
	LAST_NODE;
	F_NODE(nd_body, "lambda clause");
	break;

      case NODE_OPT_ARG:
	ANN("optional arguments");
	ANN("format: def method_name([nd_body=some], [nd_next..])");
	ANN("example: def foo(a, b=1, c); end");
	F_NODE(nd_body, "body");
	LAST_NODE;
	F_NODE(nd_next, "next");
	break;

      case NODE_KW_ARG:
	ANN("keyword arguments");
	ANN("format: def method_name([nd_body=some], [nd_next..])");
	ANN("example: def foo(a:1, b:2); end");
	F_NODE(nd_body, "body");
	LAST_NODE;
	F_NODE(nd_next, "next");
	break;

      case NODE_POSTARG:
	ANN("post arguments");
	ANN("format: *[nd_1st], [nd_2nd..] = ..");
	ANN("example: a, *rest, z = foo");
	if ((VALUE)node->nd_1st != (VALUE)-1) {
	    F_NODE(nd_1st, "rest argument");
	}
	else {
	    F_MSG(nd_1st, "rest argument", "-1 (rest argument without name)");
	}
	LAST_NODE;
	F_NODE(nd_2nd, "post arguments");
	break;

      case NODE_ARGS:
	ANN("method parameters");
	ANN("format: def method_name(.., [nd_opt=some], *[nd_rest], [nd_pid], .., &[nd_body])");
	ANN("example: def foo(a, b, opt1=1, opt2=2, *rest, y, z, &blk); end");
	F_INT(nd_ainfo->pre_args_num, "count of mandatory (pre-)arguments");
	F_NODE(nd_ainfo->pre_init, "initialization of (pre-)arguments");
	F_INT(nd_ainfo->post_args_num, "count of mandatory post-arguments");
	F_NODE(nd_ainfo->post_init, "initialization of post-arguments");
	F_ID(nd_ainfo->first_post_arg, "first post argument");
	F_ID(nd_ainfo->rest_arg, "rest argument");
	F_ID(nd_ainfo->block_arg, "block argument");
	F_NODE(nd_ainfo->opt_args, "optional arguments");
	LAST_NODE;
	F_NODE(nd_ainfo->kw_args, "keyword arguments");
	F_NODE(nd_ainfo->kw_rest_arg, "keyword rest argument");
	break;

      case NODE_SCOPE:
	ANN("new scope");
	ANN("format: [nd_tbl]: local table, [nd_args]: arguments, [nd_body]: body");
	F_CUSTOM1(nd_tbl, "local table") {
	    ID *tbl = node->nd_tbl;
	    int i;
	    int size = tbl ? (int)*tbl++ : 0;
	    if (size == 0) A("(empty)");
	    for (i = 0; i < size; i++) {
		A_ID(tbl[i]); if (i < size - 1) A(",");
	    }
	}
	F_NODE(nd_args, "arguments");
	LAST_NODE;
	F_NODE(nd_body, "body");
	break;

      default:
	rb_bug("dump_node: unknown node: %s", ruby_node_name(nd_type(node)));
    }
}

VALUE
rb_parser_dump_tree(NODE *node, int comment)
{
    VALUE buf = rb_str_new_cstr(
	"###########################################################\n"
	"## Do NOT use this node dump for any purpose other than  ##\n"
	"## debug and research.  Compatibility is not guaranteed. ##\n"
	"###########################################################\n\n"
    );
    dump_node(buf, rb_str_new_cstr("# "), comment, node);
    return buf;
}

void
rb_gc_free_node(VALUE obj)
{
    switch (nd_type(obj)) {
      case NODE_SCOPE:
	if (RNODE(obj)->nd_tbl) {
	    xfree(RNODE(obj)->nd_tbl);
	}
	break;
      case NODE_ARGS:
	if (RNODE(obj)->nd_ainfo) {
	    xfree(RNODE(obj)->nd_ainfo);
	}
	break;
      case NODE_ALLOCA:
	xfree(RNODE(obj)->u1.node);
	break;
    }
}

size_t
rb_node_memsize(VALUE obj)
{
    size_t size = 0;
    switch (nd_type(obj)) {
      case NODE_SCOPE:
	if (RNODE(obj)->nd_tbl) {
	    size += (RNODE(obj)->nd_tbl[0]+1) * sizeof(*RNODE(obj)->nd_tbl);
	}
	break;
      case NODE_ARGS:
	if (RNODE(obj)->nd_ainfo) {
	    size += sizeof(*RNODE(obj)->nd_ainfo);
	}
	break;
      case NODE_ALLOCA:
	size += RNODE(obj)->nd_cnt * sizeof(VALUE);
	break;
    }
    return size;
}

VALUE
rb_gc_mark_node(NODE *obj)
{
    switch (nd_type(obj)) {
      case NODE_IF:		/* 1,2,3 */
      case NODE_FOR:
      case NODE_ITER:
      case NODE_WHEN:
      case NODE_MASGN:
      case NODE_RESCUE:
      case NODE_RESBODY:
      case NODE_CLASS:
      case NODE_BLOCK_PASS:
      case NODE_MATCH2:
	rb_gc_mark(RNODE(obj)->u2.value);
	/* fall through */
      case NODE_BLOCK:	/* 1,3 */
      case NODE_ARRAY:
      case NODE_DSTR:
      case NODE_DXSTR:
      case NODE_DREGX:
      case NODE_DREGX_ONCE:
      case NODE_ENSURE:
      case NODE_CALL:
      case NODE_DEFS:
      case NODE_OP_ASGN1:
	rb_gc_mark(RNODE(obj)->u1.value);
	/* fall through */
      case NODE_SUPER:	/* 3 */
      case NODE_FCALL:
      case NODE_DEFN:
      case NODE_ARGS_AUX:
	return RNODE(obj)->u3.value;

      case NODE_WHILE:	/* 1,2 */
      case NODE_UNTIL:
      case NODE_AND:
      case NODE_OR:
      case NODE_CASE:
      case NODE_SCLASS:
      case NODE_DOT2:
      case NODE_DOT3:
      case NODE_FLIP2:
      case NODE_FLIP3:
      case NODE_MATCH3:
      case NODE_OP_ASGN_OR:
      case NODE_OP_ASGN_AND:
      case NODE_MODULE:
      case NODE_ALIAS:
      case NODE_VALIAS:
      case NODE_ARGSCAT:
	rb_gc_mark(RNODE(obj)->u1.value);
	/* fall through */
      case NODE_GASGN:	/* 2 */
      case NODE_LASGN:
      case NODE_DASGN:
      case NODE_DASGN_CURR:
      case NODE_IASGN:
      case NODE_IASGN2:
      case NODE_CVASGN:
      case NODE_COLON3:
      case NODE_OPT_N:
      case NODE_EVSTR:
      case NODE_UNDEF:
      case NODE_POSTEXE:
	return RNODE(obj)->u2.value;

      case NODE_HASH:	/* 1 */
      case NODE_LIT:
      case NODE_STR:
      case NODE_XSTR:
      case NODE_DEFINED:
      case NODE_MATCH:
      case NODE_RETURN:
      case NODE_BREAK:
      case NODE_NEXT:
      case NODE_YIELD:
      case NODE_COLON2:
      case NODE_SPLAT:
      case NODE_TO_ARY:
	return RNODE(obj)->u1.value;

      case NODE_SCOPE:	/* 2,3 */
      case NODE_CDECL:
      case NODE_OPT_ARG:
	rb_gc_mark(RNODE(obj)->u3.value);
	return RNODE(obj)->u2.value;

      case NODE_ARGS:	/* custom */
	{
	    struct rb_args_info *args = obj->u3.args;
	    if (args) {
		if (args->pre_init)    rb_gc_mark((VALUE)args->pre_init);
		if (args->post_init)   rb_gc_mark((VALUE)args->post_init);
		if (args->opt_args)    rb_gc_mark((VALUE)args->opt_args);
		if (args->kw_args)     rb_gc_mark((VALUE)args->kw_args);
		if (args->kw_rest_arg) rb_gc_mark((VALUE)args->kw_rest_arg);
	    }
	}
	return RNODE(obj)->u2.value;

      case NODE_ZARRAY:	/* - */
      case NODE_ZSUPER:
      case NODE_VCALL:
      case NODE_GVAR:
      case NODE_LVAR:
      case NODE_DVAR:
      case NODE_IVAR:
      case NODE_CVAR:
      case NODE_NTH_REF:
      case NODE_BACK_REF:
      case NODE_REDO:
      case NODE_RETRY:
      case NODE_SELF:
      case NODE_NIL:
      case NODE_TRUE:
      case NODE_FALSE:
      case NODE_ERRINFO:
      case NODE_BLOCK_ARG:
	break;
      case NODE_ALLOCA:
	rb_gc_mark_locations((VALUE*)RNODE(obj)->u1.value,
			     (VALUE*)RNODE(obj)->u1.value + RNODE(obj)->u3.cnt);
	rb_gc_mark(RNODE(obj)->u2.value);
	break;

      default:		/* unlisted NODE */
	rb_gc_mark_maybe(RNODE(obj)->u1.value);
	rb_gc_mark_maybe(RNODE(obj)->u2.value);
	rb_gc_mark_maybe(RNODE(obj)->u3.value);
    }
    return 0;
}