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
|
# primitives for emitting traces to a 'trace' stream, and for tests to make assertions on its contents
#
# A trace stream looks like a regular stream:
# write : int # index at which writes go
# read : int # index that we've read until
# data : (array byte) # prefixed by length as usual
# Usually the trace stream will be in a separate segment set aside for the purpose.
#
# primitives for operating on traces (arguments in quotes):
# - initialize-trace-stream: populates Trace-stream with a new segment of the given 'size'
# - trace: adds a 'line' to Trace-stream
# - check-trace-contains: scans from Trace-stream's start for a matching 'line', prints a 'message' to stderr on failure
# - check-trace-scans-to: scans from Trace-stream's read pointer for a matching 'line', prints a 'message' to stderr on failure
== data
# Handles are addresses created on the heap.
# In safe Mu they'll be fat pointers. But in SubX they're just addresses, since
# SubX programs never reclaim memory.
Trace-stream: # (handle stream byte)
0/imm32
# we don't have safe handles (fat pointers) yet
Trace-segment:
0/imm32/curr
0/imm32/limit
# Fake trace-stream for tests.
# Also illustrates the layout of the real trace-stream (segment).
_test-trace-stream: # (stream byte)
# current write index
0/imm32
# current read index
0/imm32
# length
8/imm32
# data
00 00 00 00 00 00 00 00 # 8 bytes
== code
# instruction effective address register displacement immediate
# . op subop mod rm32 base index scale r32
# . 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes
# Allocate a new segment for the trace stream, initialize its length, and save its address to Trace-stream.
# The Trace-stream segment will consist of variable-length lines separated by newlines (0x0a)
initialize-trace-stream: # n : int
# . prologue
55/push-ebp
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
# . save registers
50/push-eax
51/push-ecx
# ecx = n
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 1/r32/ecx 8/disp8 . # copy *(ebp+8) to ecx
# Trace-segment = new-segment(n)
# . . push args
68/push Trace-segment/imm32
51/push-ecx
# . . call
e8/call new-segment/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
# copy Trace-segment->curr to *Trace-stream
8b/copy 0/mod/indirect 5/rm32/.disp32 . . 0/r32/eax Trace-segment/disp32 # copy *Trace-segment to eax
#? # watch point to catch Trace-stream leaks
#? $watch-1:
89/copy 0/mod/indirect 5/rm32/.disp32 . . 0/r32/eax Trace-stream/disp32 # copy eax to *Trace-stream
# Trace-stream->length = n - 12
# . ecx -= 12
81 5/subop/subtract 3/mod/direct 1/rm32/ecx . . . . . 0xc/imm32 # subtract from ecx
# . Trace-stream->length = ecx
89/copy 1/mod/*+disp8 0/rm32/eax . . . 1/r32/ecx 8/disp8 . # copy ecx to *(eax+8)
$initialize-trace-stream:end:
# . restore registers
59/pop-to-ecx
58/pop-to-eax
# . epilogue
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
5d/pop-to-ebp
c3/return
# Append a string to the given trace stream.
# Silently give up if it's already full. Or truncate the string if there isn't enough room.
trace: # line : (addr array byte)
# . prologue
55/push-ebp
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
# . save registers
50/push-eax
51/push-ecx
52/push-edx
53/push-ebx
56/push-esi
57/push-edi
# var edi : (addr stream byte) = *Trace-stream
8b/copy 0/mod/indirect 5/rm32/.disp32 . . 7/r32/edi Trace-stream/disp32 # copy *Trace-stream to edi
# esi = line
8b/copy 1/mod/*+disp8 5/rm32/ebp . . 6/r32/esi 8/disp8 . # copy *(ebp+8) to esi
# var ecx : int = t->write
8b/copy 0/mod/indirect 7/rm32/edi . . . 1/r32/ecx . . # copy *edi to ecx
# var edx : int = t->length
8b/copy 1/mod/*+disp8 7/rm32/edi . . . 2/r32/edx 8/disp8 . # copy *(edi+8) to edx
# eax = _append-3(&t->data[t->write], &t->data[t->length], line)
# . . push line
56/push-esi
# . . push &t->data[t->length]
8d/copy-address 1/mod/*+disp8 4/rm32/sib 7/base/edi 2/index/edx . 3/r32/ebx 0xc/disp8 . # copy edi+edx+12 to ebx
53/push-ebx
# . . push &t->data[t->write]
8d/copy-address 1/mod/*+disp8 4/rm32/sib 7/base/edi 1/index/ecx . 3/r32/ebx 0xc/disp8 . # copy edi+ecx+12 to ebx
53/push-ebx
# . . call
e8/call _append-3/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
# if (eax == 0) return
3d/compare-eax-and 0/imm32
74/jump-if-equal $trace:end/disp8
# t->write += eax
01/add 0/mod/indirect 7/rm32/edi . . . 0/r32/eax . . # add eax to *edi
# refresh ecx = t->write
8b/copy 0/mod/indirect 7/rm32/edi . . . 1/r32/ecx . . # copy *edi to ecx
# eax = _append-3(&t->data[t->write], &t->data[t->length], line)
# . . push line
68/push Newline/imm32
# . . push &t->data[t->length]
8d/copy-address 1/mod/*+disp8 4/rm32/sib 7/base/edi 2/index/edx . 3/r32/ebx 0xc/disp8 . # copy edi+edx+12 to ebx
53/push-ebx
# . . push &t->data[t->write]
8d/copy-address 1/mod/*+disp8 4/rm32/sib 7/base/edi 1/index/ecx . 3/r32/ebx 0xc/disp8 . # copy edi+ecx+12 to ebx
53/push-ebx
# . . call
e8/call _append-3/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
# t->write += eax
01/add 0/mod/indirect 7/rm32/edi . . . 0/r32/eax . . # add eax to *edi
$trace:end:
# . restore registers
5f/pop-to-edi
5e/pop-to-esi
5b/pop-to-ebx
5a/pop-to-edx
59/pop-to-ecx
58/pop-to-eax
# . epilogue
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
5d/pop-to-ebp
c3/return
test-trace-single:
# push *Trace-stream
ff 6/subop/push 0/mod/indirect 5/rm32/.disp32 . . . Trace-stream/disp32 # push *Trace-stream
# *Trace-stream = _test-trace-stream
b8/copy-to-eax _test-trace-stream/imm32
89/copy 0/mod/indirect 5/rm32/.disp32 . . 0/r32/eax Trace-stream/disp32 # copy eax to *Trace-stream
# clear-trace-stream()
e8/call clear-trace-stream/disp32
# trace("Ab")
# . . push args
68/push "Ab"/imm32
# . . call
e8/call trace/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# check-ints-equal(*_test-trace-stream->data, 41/A 62/b 0a/newline 00, msg)
# . . push args
68/push "F - test-trace-single"/imm32
68/push 0x0a6241/imm32/Ab-newline
# . . push *_test-trace-stream->data
b8/copy-to-eax _test-trace-stream/imm32
ff 6/subop/push 1/mod/*+disp8 0/rm32/eax . . . . 0xc/disp8 . # push *(eax+12)
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
# pop into *Trace-stream
8f 0/subop/pop 0/mod/indirect 5/rm32/.disp32 . . . Trace-stream/disp32 # pop into *Trace-stream
# end
c3/return
test-trace-appends:
# push *Trace-stream
ff 6/subop/push 0/mod/indirect 5/rm32/.disp32 . . . Trace-stream/disp32 # push *Trace-stream
# *Trace-stream = _test-trace-stream
b8/copy-to-eax _test-trace-stream/imm32
89/copy 0/mod/indirect 5/rm32/.disp32 . . 0/r32/eax Trace-stream/disp32 # copy eax to *Trace-stream
# clear-trace-stream()
e8/call clear-trace-stream/disp32
# trace("C")
# . . push args
68/push "C"/imm32
# . . call
e8/call trace/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# trace("D")
# . . push args
68/push "D"/imm32
# . . call
e8/call trace/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# check-ints-equal(*_test-trace-stream->data, 43/C 0a/newline 44/D 0a/newline, msg)
# . . push args
68/push "F - test-trace-appends"/imm32
68/push 0x0a440a43/imm32/C-newline-D-newline
# . . push *_test-trace-stream->data
b8/copy-to-eax _test-trace-stream/imm32
ff 6/subop/push 1/mod/*+disp8 0/rm32/eax . . . . 0xc/disp8 . # push *(eax+12)
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
# pop into *Trace-stream
8f 0/subop/pop 0/mod/indirect 5/rm32/.disp32 . . . Trace-stream/disp32 # pop into *Trace-stream
# end
c3/return
test-trace-empty-line:
# push *Trace-stream
ff 6/subop/push 0/mod/indirect 5/rm32/.disp32 . . . Trace-stream/disp32 # push *Trace-stream
# *Trace-stream = _test-trace-stream
b8/copy-to-eax _test-trace-stream/imm32
89/copy 0/mod/indirect 5/rm32/.disp32 . . 0/r32/eax Trace-stream/disp32 # copy eax to *Trace-stream
# clear-trace-stream()
e8/call clear-trace-stream/disp32
# trace("")
# . . push args
68/push ""/imm32
# . . call
e8/call trace/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# check-ints-equal(*_test-trace-stream->data, 0, msg)
# . . push args
68/push "F - test-trace-empty-line"/imm32
68/push 0/imm32
# . . push *_test-trace-stream->data
b8/copy-to-eax _test-trace-stream/imm32
ff 6/subop/push 1/mod/*+disp8 0/rm32/eax . . . . 0xc/disp8 . # push *(eax+12)
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
# pop into *Trace-stream
8f 0/subop/pop 0/mod/indirect 5/rm32/.disp32 . . . Trace-stream/disp32 # pop into *Trace-stream
# end
c3/return
check-trace-contains: # line : (addr string), msg : (addr string)
# . prologue
55/push-ebp
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
# rewind-stream(*Trace-stream)
# . . push args
ff 6/subop/push 0/mod/indirect 5/rm32/.disp32 . . . Trace-stream/disp32 # push *Trace-stream
# . . call
e8/call rewind-stream/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# check-trace-scans-to(line, msg)
# . . push args
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 0xc/disp8 . # push *(ebp+12)
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 8/disp8 . # push *(ebp+8)
# . . call
e8/call check-trace-scans-to/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
$check-trace-contains:end:
# . epilogue
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
5d/pop-to-ebp
c3/return
check-trace-scans-to: # line : (addr string), msg : (addr string)
# . prologue
55/push-ebp
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
# . save registers
50/push-eax
# eax = trace-scan(line)
# . . push args
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 8/disp8 . # push *(ebp+8)
# . . call
e8/call trace-scan/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# check-ints-equal(eax, 1, msg)
# . . push args
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 0xc/disp8 . # push *(ebp+12)
68/push 1/imm32
50/push-eax
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
$check-trace-scans-to:end:
# . restore registers
58/pop-to-eax
# . epilogue
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
5d/pop-to-ebp
c3/return
# Start scanning from Trace-stream->read for 'line'. If found, update Trace-stream->read and return true.
trace-scan: # line : (addr array byte) -> result/eax : boolean
# pseudocode:
# push Trace-stream->read
# while true:
# if Trace-stream->read >= Trace-stream->write
# break
# if next-line-matches?(Trace-stream, line)
# skip-next-line(Trace-stream)
# dump saved copy of Trace-stream->read
# return true
# skip-next-line(Trace-stream)
# pop saved copy of Trace-stream->read
# return false
#
# . prologue
55/push-ebp
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
# . save registers
51/push-ecx
56/push-esi
# esi = *Trace-stream
8b/copy 0/mod/indirect 5/rm32/.disp32 . . 6/r32/esi Trace-stream/disp32 # copy *Trace-stream to esi
# ecx = Trace-stream->write
8b/copy 0/mod/indirect 6/rm32/esi . . . 1/r32/ecx . # copy *esi to ecx
# push Trace-stream->read
ff 6/subop/push 1/mod/*+disp8 6/rm32/esi . . . . 4/disp8 . # push *(esi+4)
$trace-scan:loop:
# if (Trace-stream->read >= Trace-stream->write) return false
39/compare 1/mod/*+disp8 6/rm32/esi . . . 1/r32/ecx 4/disp8 . # compare ecx with *(esi+4)
7d/jump-if-greater-or-equal $trace-scan:false/disp8
# eax = next-line-matches?(Trace-stream, line)
# . . push args
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 8/disp8 . # push *(ebp+8)
56/push-esi
# . . call
e8/call next-line-matches?/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
# if (eax == false) continue
3d/compare-eax-and 0/imm32/false
74/jump-if-equal $trace-scan:continue/disp8
$trace-scan:true:
# skip-next-line(Trace-stream)
# . . push args
56/push-esi
# . . call
e8/call skip-next-line/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# dump saved copy of Trace-stream->read
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# return true
b8/copy-to-eax 1/imm32/true
eb/jump $trace-scan:end/disp8
$trace-scan:continue:
# skip-next-line(Trace-stream)
# . . push args
56/push-esi
# . . call
e8/call skip-next-line/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
eb/jump $trace-scan:loop/disp8
$trace-scan:false:
# restore saved copy of Trace-stream->read
8f 0/subop/pop 1/mod/*+disp8 6/rm32/esi . . . . 4/disp8 . # pop to *(esi+4)
# return false
b8/copy-to-eax 0/imm32/false
$trace-scan:end:
# . restore registers
59/pop-to-ecx
# . epilogue
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
5d/pop-to-ebp
c3/return
test-trace-scan-first:
# push *Trace-stream
ff 6/subop/push 0/mod/indirect 5/rm32/.disp32 . . . Trace-stream/disp32 # push *Trace-stream
# setup
# . *Trace-stream = _test-trace-stream
b8/copy-to-eax _test-trace-stream/imm32
89/copy 0/mod/indirect 5/rm32/.disp32 . . 0/r32/eax Trace-stream/disp32 # copy eax to *Trace-stream
# . clear-trace-stream()
e8/call clear-trace-stream/disp32
# . trace("Ab")
# . . push args
68/push "Ab"/imm32
# . . call
e8/call trace/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# eax = trace-scan("Ab")
# . . push args
68/push "Ab"/imm32
# . . call
e8/call trace-scan/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# check-ints-equal(eax, 1, msg)
# . . push args
68/push "F - test-trace-scan-first"/imm32
68/push 1/imm32
50/push-eax
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
# pop into *Trace-stream
8f 0/subop/pop 0/mod/indirect 5/rm32/.disp32 . . . Trace-stream/disp32 # pop into *Trace-stream
# . end
c3/return
test-trace-scan-skips-lines-until-found:
# push *Trace-stream
ff 6/subop/push 0/mod/indirect 5/rm32/.disp32 . . . Trace-stream/disp32 # push *Trace-stream
# setup
# . *Trace-stream = _test-trace-stream
b8/copy-to-eax _test-trace-stream/imm32
89/copy 0/mod/indirect 5/rm32/.disp32 . . 0/r32/eax Trace-stream/disp32 # copy eax to *Trace-stream
# . clear-trace-stream()
e8/call clear-trace-stream/disp32
# . trace("Ab")
# . . push args
68/push "Ab"/imm32
# . . call
e8/call trace/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# . trace("cd")
# . . push args
68/push "cd"/imm32
# . . call
e8/call trace/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# eax = trace-scan("cd")
# . . push args
68/push "cd"/imm32
# . . call
e8/call trace-scan/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# check-ints-equal(eax, 1, msg)
# . . push args
68/push "F - test-trace-scan-skips-lines-until-found"/imm32
68/push 1/imm32
50/push-eax
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
# pop into *Trace-stream
8f 0/subop/pop 0/mod/indirect 5/rm32/.disp32 . . . Trace-stream/disp32 # pop into *Trace-stream
# . end
c3/return
test-trace-second-scan-starts-where-first-left-off:
# push *Trace-stream
ff 6/subop/push 0/mod/indirect 5/rm32/.disp32 . . . Trace-stream/disp32 # push *Trace-stream
# setup
# . *Trace-stream = _test-trace-stream
b8/copy-to-eax _test-trace-stream/imm32
89/copy 0/mod/indirect 5/rm32/.disp32 . . 0/r32/eax Trace-stream/disp32 # copy eax to *Trace-stream
# . clear-trace-stream()
e8/call clear-trace-stream/disp32
# . trace("Ab")
# . . push args
68/push "Ab"/imm32
# . . call
e8/call trace/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# . eax = trace-scan("Ab")
# . . push args
68/push "Ab"/imm32
# . . call
e8/call trace-scan/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# second scan fails
# . eax = trace-scan("Ab")
# . . push args
68/push "Ab"/imm32
# . . call
e8/call trace-scan/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# check-ints-equal(eax, 0, msg)
# . . push args
68/push "F - test-trace-second-scan-starts-where-first-left-off"/imm32
68/push 0/imm32
50/push-eax
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
# pop into *Trace-stream
8f 0/subop/pop 0/mod/indirect 5/rm32/.disp32 . . . Trace-stream/disp32 # pop into *Trace-stream
# . end
c3/return
test-trace-scan-failure-leaves-read-index-untouched:
# push *Trace-stream
ff 6/subop/push 0/mod/indirect 5/rm32/.disp32 . . . Trace-stream/disp32 # push *Trace-stream
# setup
# . *Trace-stream = _test-trace-stream
b8/copy-to-eax _test-trace-stream/imm32
89/copy 0/mod/indirect 5/rm32/.disp32 . . 0/r32/eax Trace-stream/disp32 # copy eax to *Trace-stream
# . clear-trace-stream()
e8/call clear-trace-stream/disp32
# . trace("Ab")
# . . push args
68/push "Ab"/imm32
# . . call
e8/call trace/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# . check-ints-equal(_test-trace-stream->read, 0, msg)
# . . push args
68/push "F - test-trace-second-scan-starts-where-first-left-off/precondition-failure"/imm32
68/push 0/imm32
b8/copy-to-eax _test-trace-stream/imm32
ff 6/subop/push 1/mod/*+disp8 0/rm32/eax . . . . 4/disp8 . # push *(eax+4)
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
# perform a failing scan
# . eax = trace-scan("Ax")
# . . push args
68/push "Ax"/imm32
# . . call
e8/call trace-scan/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# no change in read index
# . check-ints-equal(_test-trace-stream->read, 0, msg)
# . . push args
68/push "F - test-trace-second-scan-starts-where-first-left-off"/imm32
68/push 0/imm32
b8/copy-to-eax _test-trace-stream/imm32
ff 6/subop/push 1/mod/*+disp8 0/rm32/eax . . . . 4/disp8 . # push *(eax+4)
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
# pop into *Trace-stream
8f 0/subop/pop 0/mod/indirect 5/rm32/.disp32 . . . Trace-stream/disp32 # pop into *Trace-stream
# . end
c3/return
next-line-matches?: # t : (addr stream byte), line : (addr array byte) -> result/eax : boolean
# pseudocode:
# while true:
# if (currl >= maxl) break
# if (currt >= maxt) return false
# if (*currt != *currl) return false
# ++currt
# ++currl
# return *currt == '\n'
#
# . prologue
55/push-ebp
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
# . save registers
51/push-ecx
52/push-edx
53/push-ebx
56/push-esi
57/push-edi
# edx = line
8b/copy 1/mod/*+disp8 5/rm32/ebp . . 2/r32/edx 0xc/disp8 . # copy *(ebp+12) to edx
# var currl/esi : (addr byte) = line->data
# . esi = line/edx->data
8d/copy-address 1/mod/*+disp8 2/rm32/edx . . . 6/r32/esi 4/disp8 . # copy edx+4 to esi
# var maxl/ecx : (addr byte) = &line->data[line->size]
# . eax = line/edx->size
8b/copy 0/mod/indirect 2/rm32/edx . . 0/r32/eax . . # copy *edx to eax
# . maxl = &line->data[line->size]
8d/copy-address 0/mod/indirect 4/rm32/sib 6/base/esi 0/index/eax . 1/r32/ecx . . # copy edx+eax to ecx
# edi = t
8b/copy 1/mod/*+disp8 5/rm32/ebp . . 7/r32/edi 8/disp8 . # copy *(ebp+8) to edi
# var ebx : (addr byte) = t->data
8d/copy-address 1/mod/*+disp8 7/rm32/edi . . . 3/r32/ebx 0xc/disp8 . # copy edi+12 to ebx
# var maxt/edx : (addr byte) = &t->data[t->write]
# . eax = t->write
8b/copy 0/mod/indirect 7/rm32/edi . . 0/r32/eax . . # copy *edi to eax
# . maxt = &t->data[t->write]
8d/copy-address 0/mod/indirect 4/rm32/sib 3/base/ebx 0/index/eax . 2/r32/edx . . # copy ebx+eax to edx
# var currt/edi : (addr byte) = &t->data[t->read]
# . eax = t/edi->read
8b/copy 1/mod/*+disp8 7/rm32/edi . . 0/r32/eax 4/disp8 . # copy *(edi+4) to eax
# . currt = &t->data[t->read]
8d/copy-address 0/mod/indirect 4/rm32/sib 3/base/ebx 0/index/eax . 7/r32/edi . . # copy ebx+eax to edi
$next-line-matches?:loop:
# if (currl >= maxl) break
39/compare 3/mod/direct 6/rm32/esi . . . 1/r32/ecx . . # compare esi and ecx
73/jump-if-greater-or-equal-unsigned $next-line-matches?:break/disp8
# if (currt >= maxt) return false
# . eax = false
b8/copy-to-eax 0/imm32/false
39/compare 3/mod/direct 7/rm32/edi . . . 2/r32/edx . . # compare edi and edx
73/jump-if-greater-or-equal-unsigned $next-line-matches?:end/disp8
# if (*currt != *currl) return false
31/xor 3/mod/direct 0/rm32/eax . . . 0/r32/eax . . # clear eax
31/xor 3/mod/direct 3/rm32/eax . . . 3/r32/eax . . # clear ebx
# . eax : byte = *currt
8a/copy-byte 0/mod/indirect 7/rm32/edi . . 0/r32/eax . . # copy *edi to eax
# . ebx : byte = *currl
8a/copy-byte 0/mod/indirect 6/rm32/esi . . 3/r32/ebx . . # copy *esi to ebx
# . eax >= ebx
39/compare 3/mod/direct 0/rm32/eax . . . 3/r32/ebx . . # compare eax and ebx
# . eax = false
b8/copy-to-eax 0/imm32/false
75/jump-if-not-equal $next-line-matches?:end/disp8
# ++currt
47/increment-edi
# ++currl
46/increment-esi
eb/jump $next-line-matches?:loop/disp8
$next-line-matches?:break:
# return *currt == '\n'
31/xor 3/mod/direct 0/rm32/eax . . . 0/r32/eax . . # clear eax
# . eax : byte = *currt
8a/copy-byte 0/mod/indirect 7/rm32/edi . . 0/r32/eax . . # copy *edi to eax
3d/compare-eax-and 0xa/imm32/newline
# . eax = false
b8/copy-to-eax 1/imm32/true
74/jump-if-equal $next-line-matches?:end/disp8
b8/copy-to-eax 0/imm32/true
$next-line-matches?:end:
# . restore registers
5f/pop-to-edi
5e/pop-to-esi
5b/pop-to-ebx
5a/pop-to-edx
59/pop-to-ecx
# . epilogue
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
5d/pop-to-ebp
c3/return
test-next-line-matches?-no-match-1:
# next line of "ABABA" does not match "blah blah"
# . eax = next-line-matches?(_test-stream-line-ABABA, "blah blah")
# . . push args
68/push "blah blah"/imm32
68/push _test-stream-line-ABABA/imm32
# . . call
e8/call next-line-matches?/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
# . check-ints-equal(eax, 0, msg)
# . . push args
68/push "F - test-next-line-matches?-no-match-1"/imm32
68/push 0/imm32
50/push-eax
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
c3/return
test-next-line-matches?-no-match-2:
# next line of "ABABA" does not match ""
# . eax = next-line-matches?(_test-stream-line-ABABA, "")
# . . push args
68/push ""/imm32
68/push _test-stream-line-ABABA/imm32
# . . call
e8/call next-line-matches?/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
# . check-ints-equal(eax, 0, msg)
# . . push args
68/push "F - test-next-line-matches?-no-match-2"/imm32
68/push 0/imm32
50/push-eax
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
c3/return
test-next-line-matches?-no-match-3:
# next line of "ABABA" does not match "AA"
# . eax = next-line-matches?(_test-stream-line-ABABA, "AA")
# . . push args
68/push "AA"/imm32
68/push _test-stream-line-ABABA/imm32
# . . call
e8/call next-line-matches?/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
# . check-ints-equal(eax, 0, msg)
# . . push args
68/push "F - test-next-line-matches?-no-match-3"/imm32
68/push 0/imm32
50/push-eax
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
c3/return
test-next-line-matches?-match:
# next line of "ABABA" matches "ABABA"
# . eax = next-line-matches?(_test-stream-line-ABABA, "ABABA")
# . . push args
68/push "ABABA"/imm32
68/push _test-stream-line-ABABA/imm32
# . . call
e8/call next-line-matches?/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
# . check-ints-equal(eax, 1, msg)
# . . push args
68/push "F - test-next-line-matches?-match"/imm32
68/push 1/imm32
50/push-eax
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
c3/return
# move t->read to _after_ next newline
skip-next-line: # t : (addr stream byte)
# pseudocode:
# max = &t->data[t->write]
# i = t->read
# curr = &t->data[t->read]
# while true
# if (curr >= max) break
# ++i
# if (*curr == '\n') break
# ++curr
# t->read = i
#
# . prologue
55/push-ebp
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
# . save registers
50/push-eax
51/push-ecx
52/push-edx
53/push-ebx
# ecx = t
8b/copy 1/mod/*+disp8 5/rm32/ebp . . 1/r32/ecx 8/disp8 . # copy *(ebp+8) to ecx
# edx = t->data
8d/copy-address 1/mod/*+disp8 1/rm32/ecx . . . 2/r32/edx 0xc/disp8 . # copy ecx+12 to edx
# eax = t->write
8b/copy 0/mod/indirect 1/rm32/ecx . . . 0/r32/eax . . # copy *ecx to eax
# var max/ebx : (addr byte) = &t->data[t->write]
8d/copy-address 0/mod/indirect 4/rm32/sib 2/base/edx 0/index/eax . 3/r32/ebx . . # copy edx+eax to ebx
# eax = t->read
8b/copy 1/mod/*+disp8 1/rm32/ecx . . . 0/r32/eax 4/disp8 . # copy *(ecx+4) to edx
# var curr/ecx : (addr byte) = &t->data[t->read]
8d/copy-address 0/mod/indirect 4/rm32/sib 2/base/edx 0/index/eax . 1/r32/ecx . . # copy edx+eax to ecx
# var i/edx : int = t->read
89/copy 3/mod/direct 2/rm32/edx . . . 0/r32/eax . . # copy eax to edx
$skip-next-line:loop:
# if (curr >= max) break
39/compare 3/mod/direct 1/rm32/ecx . . . 3/r32/ebx . . # compare ecx and ebx
73/jump-if-greater-or-equal-unsigned $skip-next-line:end/disp8
# ++i
42/increment-edx
# if (*curr == '\n') break
31/xor 3/mod/direct 0/rm32/eax . . . 0/r32/eax . . # clear eax
8a/copy-byte 0/mod/indirect 1/rm32/ecx . . . 0/r32/eax . . # copy *ecx to eax
3d/compare-eax-and 0a/imm32/newline
74/jump-if-equal $skip-next-line:end/disp8
# ++curr
41/increment-ecx
# loop
eb/jump $skip-next-line:loop/disp8
$skip-next-line:end:
# ecx = t
8b/copy 1/mod/*+disp8 5/rm32/ebp . . 1/r32/ecx 8/disp8 . # copy *(ebp+8) to ecx
# t->read = i
89/copy 1/mod/*+disp8 1/rm32/ecx . . . 2/r32/edx 4/disp8 . # copy edx to *(ecx+4)
# . restore registers
5b/pop-to-ebx
5a/pop-to-edx
59/pop-to-ecx
58/pop-to-eax
# . epilogue
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
5d/pop-to-ebp
c3/return
test-skip-next-line-empty:
# skipping next line in empty stream leaves read pointer at 0
# . skip-next-line(_test-stream-empty)
# . . push args
68/push _test-stream-empty/imm32
# . . call
e8/call skip-next-line/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# . check-ints-equal(_test-stream-empty->read, 0, msg)
# . . push args
68/push "F - test-skip-next-line-empty"/imm32
68/push 0/imm32
b8/copy-to-eax _test-stream-empty/imm32
8b/copy 1/mod/*+disp8 0/rm32/eax . . . 0/r32/eax 4/disp8 . # copy *(eax+4) to eax
50/push-eax
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
c3/return
test-skip-next-line-filled:
# skipping next line increments read pointer by length of line + 1 (for newline)
# . skip-next-line(_test-stream-filled)
# . . push args
68/push _test-stream-filled/imm32
# . . call
e8/call skip-next-line/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# . check-ints-equal(_test-stream-filled->read, 5, msg)
# . . push args
68/push "F - test-skip-next-line-filled"/imm32
68/push 5/imm32
b8/copy-to-eax _test-stream-filled/imm32
8b/copy 1/mod/*+disp8 0/rm32/eax . . . 0/r32/eax 4/disp8 . # copy *(eax+4) to eax
50/push-eax
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
c3/return
clear-trace-stream:
# . prologue
55/push-ebp
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
# clear-stream(*Trace-stream)
# . . push args
ff 6/subop/push 0/mod/indirect 5/rm32/.disp32 . . . Trace-stream/disp32 # push *Trace-stream
# . . call
e8/call clear-stream/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
$clear-trace-stream:end:
# . epilogue
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
5d/pop-to-ebp
c3/return
# - helpers
# 3-argument variant of _append
_append-3: # out : (addr byte), outend : (addr byte), s : (addr array byte) -> num_bytes_appended/eax
# . prologue
55/push-ebp
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
# . save registers
51/push-ecx
# eax = _append-4(out, outend, &s->data[0], &s->data[s->length])
# . . push &s->data[s->length]
8b/copy 1/mod/*+disp8 5/rm32/ebp . . 0/r32/eax 0x10/disp8 . # copy *(ebp+16) to eax
8b/copy 0/mod/indirect 0/rm32/eax . . . 1/r32/ecx . . # copy *eax to ecx
8d/copy-address 1/mod/*+disp8 4/rm32/sib 0/base/eax 1/index/ecx . 1/r32/ecx 4/disp8 . # copy eax+ecx+4 to ecx
51/push-ecx
# . . push &s->data[0]
8d/copy-address 1/mod/*+disp8 0/rm32/eax . . . 1/r32/ecx 4/disp8 . # copy eax+4 to ecx
51/push-ecx
# . . push outend
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 0xc/disp8 . # push *(ebp+12)
# . . push out
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 8/disp8 . # push *(ebp+8)
# . . call
e8/call _append-4/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0x10/imm32 # add to esp
$_append-3:end:
# . restore registers
59/pop-to-ecx
# . epilogue
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
5d/pop-to-ebp
c3/return
# 4-argument variant of _append
_append-4: # out : (addr byte), outend : (addr byte), in : (addr byte), inend : (addr byte) -> num_bytes_appended/eax : int
# . prologue
55/push-ebp
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
# . save registers
51/push-ecx
52/push-edx
53/push-ebx
56/push-esi
57/push-edi
# num_bytes_appended = 0
b8/copy-to-eax 0/imm32
# edi = out
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 7/r32/edi 8/disp8 . # copy *(ebp+8) to edi
# edx = outend
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 2/r32/edx 0xc/disp8 . # copy *(ebp+12) to edx
# esi = in
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 6/r32/esi 0x10/disp8 . # copy *(ebp+16) to esi
# ecx = inend
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 1/r32/ecx 0x14/disp8 . # copy *(ebp+20) to ecx
$_append-4:loop:
# if (in >= inend) break
39/compare 3/mod/direct 6/rm32/esi . . . 1/r32/ecx . . # compare esi with ecx
73/jump-if-greater-or-equal-unsigned $_append-4:end/disp8
# if (out >= outend) abort # just to catch test failures fast
39/compare 3/mod/direct 7/rm32/edi . . . 2/r32/edx . . # compare edi with edx
73/jump-if-greater-or-equal-unsigned $_append-4:abort/disp8
# *out = *in
8a/copy-byte 0/mod/indirect 6/rm32/esi . . . 3/r32/BL . . # copy byte at *esi to BL
88/copy-byte 0/mod/indirect 7/rm32/edi . . . 3/r32/BL . . # copy byte at BL to *edi
# ++num_bytes_appended
40/increment-eax
# ++in
46/increment-esi
# ++out
47/increment-edi
eb/jump $_append-4:loop/disp8
$_append-4:end:
# . restore registers
5f/pop-to-edi
5e/pop-to-esi
5b/pop-to-ebx
5a/pop-to-edx
59/pop-to-ecx
# . epilogue
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
5d/pop-to-ebp
c3/return
$_append-4:abort:
# . _write(2/stderr, error)
# . . push args
68/push "stream overflow\n"/imm32
68/push 2/imm32/stderr
# . . call
e8/call _write/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
# . syscall(exit, 1)
bb/copy-to-ebx 1/imm32
b8/copy-to-eax 1/imm32/exit
cd/syscall 0x80/imm8
# never gets here
== data
_test-stream-line-ABABA: # (stream byte)
# write
8/imm32
# read
0/imm32
# length
8/imm32
# data
41 42 41 42 41 0a 00 00 # 8 bytes
_test-stream-empty: # (stream byte)
# write
0/imm32
# read
0/imm32
# length
8/imm32
# data
00 00 00 00 00 00 00 00 # 8 bytes
_test-stream-filled: # (stream byte)
# write
8/imm32
# read
0/imm32
# length
8/imm32
# data
41 41 41 41 0a 41 41 41 # 8 bytes
# . . vim:nowrap:textwidth=0
|