summaryrefslogtreecommitdiff
path: root/test/lit/passes/dae-gc-refine-params.wast
blob: a6cfb7ac571e7fc4e6480544bf035b7efdaf35d3 (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
;; NOTE: Assertions have been generated by update_lit_checks.py and should not be edited.
;; RUN: wasm-opt %s -all --dae -S -o - | filecheck %s
;; RUN: wasm-opt %s -all --dae --nominal -S -o - | filecheck %s --check-prefix NOMNL

(module
 ;; CHECK:      (type ${} (struct ))

 ;; CHECK:      (type ${i32} (struct (field i32)))
 ;; NOMNL:      (type ${} (struct_subtype  data))

 ;; NOMNL:      (type ${i32} (struct_subtype (field i32) ${}))
 (type ${i32} (struct_subtype (field i32) ${}))

 (type ${} (struct))

 ;; CHECK:      (type ${f64} (struct (field f64)))

 ;; CHECK:      (type ${i32_i64} (struct (field i32) (field i64)))
 ;; NOMNL:      (type ${f64} (struct_subtype (field f64) ${}))

 ;; NOMNL:      (type ${i32_i64} (struct_subtype (field i32) (field i64) ${i32}))
 (type ${i32_i64} (struct_subtype (field i32) (field i64) ${i32}))

 (type ${f64} (struct_subtype (field f64) ${}))

 ;; CHECK:      (type ${i32_f32} (struct (field i32) (field f32)))
 ;; NOMNL:      (type ${i32_f32} (struct_subtype (field i32) (field f32) ${i32}))
 (type ${i32_f32} (struct_subtype (field i32) (field f32) ${i32}))

 ;; CHECK:      (func $call-various-params-no
 ;; CHECK-NEXT:  (call $various-params-no
 ;; CHECK-NEXT:   (call $get_{})
 ;; CHECK-NEXT:   (call $get_{i32})
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT:  (call $various-params-no
 ;; CHECK-NEXT:   (call $get_{i32})
 ;; CHECK-NEXT:   (call $get_{f64})
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT: )
 ;; NOMNL:      (func $call-various-params-no (type $none_=>_none)
 ;; NOMNL-NEXT:  (call $various-params-no
 ;; NOMNL-NEXT:   (call $get_{})
 ;; NOMNL-NEXT:   (call $get_{i32})
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT:  (call $various-params-no
 ;; NOMNL-NEXT:   (call $get_{i32})
 ;; NOMNL-NEXT:   (call $get_{f64})
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT: )
 (func $call-various-params-no
  ;; The first argument gets {} and {i32}; the second {i32} and {f64}; none of
  ;; those pairs can be optimized. Note that we do not pass in all nulls, as
  ;; all nulls are identical and we could do other optimization work due to
  ;; that.
  (call $various-params-no
   (call $get_{})
   (call $get_{i32})
  )
  (call $various-params-no
   (call $get_{i32})
   (call $get_{f64})
  )
 )
 ;; This function is called in ways that do not allow us to alter the types of
 ;; its parameters (see last function).
 ;; CHECK:      (func $various-params-no (param $x (ref null ${})) (param $y (ref null ${}))
 ;; CHECK-NEXT:  (drop
 ;; CHECK-NEXT:   (local.get $x)
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT:  (drop
 ;; CHECK-NEXT:   (local.get $y)
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT: )
 ;; NOMNL:      (func $various-params-no (type $ref?|${}|_ref?|${}|_=>_none) (param $x (ref null ${})) (param $y (ref null ${}))
 ;; NOMNL-NEXT:  (drop
 ;; NOMNL-NEXT:   (local.get $x)
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT:  (drop
 ;; NOMNL-NEXT:   (local.get $y)
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT: )
 (func $various-params-no (param $x (ref null ${})) (param $y (ref null ${}))
  ;; "Use" the locals to avoid other optimizations kicking in.
  (drop (local.get $x))
  (drop (local.get $y))
 )

 ;; CHECK:      (func $get_{} (result (ref null ${}))
 ;; CHECK-NEXT:  (unreachable)
 ;; CHECK-NEXT: )
 ;; NOMNL:      (func $get_{} (type $none_=>_ref?|${}|) (result (ref null ${}))
 ;; NOMNL-NEXT:  (unreachable)
 ;; NOMNL-NEXT: )
 (func $get_{} (result (ref null ${}))
  (unreachable)
 )
 ;; CHECK:      (func $get_{i32} (result (ref null ${i32}))
 ;; CHECK-NEXT:  (unreachable)
 ;; CHECK-NEXT: )
 ;; NOMNL:      (func $get_{i32} (type $none_=>_ref?|${i32}|) (result (ref null ${i32}))
 ;; NOMNL-NEXT:  (unreachable)
 ;; NOMNL-NEXT: )
 (func $get_{i32} (result (ref null ${i32}))
  (unreachable)
 )
 ;; CHECK:      (func $get_{f64} (result (ref null ${f64}))
 ;; CHECK-NEXT:  (unreachable)
 ;; CHECK-NEXT: )
 ;; NOMNL:      (func $get_{f64} (type $none_=>_ref?|${f64}|) (result (ref null ${f64}))
 ;; NOMNL-NEXT:  (unreachable)
 ;; NOMNL-NEXT: )
 (func $get_{f64} (result (ref null ${f64}))
  (unreachable)
 )

 ;; CHECK:      (func $call-various-params-yes
 ;; CHECK-NEXT:  (call $various-params-yes
 ;; CHECK-NEXT:   (call $get_null_{i32})
 ;; CHECK-NEXT:   (i32.const 0)
 ;; CHECK-NEXT:   (call $get_null_{i32})
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT:  (call $various-params-yes
 ;; CHECK-NEXT:   (call $get_null_{i32})
 ;; CHECK-NEXT:   (i32.const 1)
 ;; CHECK-NEXT:   (call $get_null_{i32_i64})
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT: )
 ;; NOMNL:      (func $call-various-params-yes (type $none_=>_none)
 ;; NOMNL-NEXT:  (call $various-params-yes
 ;; NOMNL-NEXT:   (call $get_null_{i32})
 ;; NOMNL-NEXT:   (i32.const 0)
 ;; NOMNL-NEXT:   (call $get_null_{i32})
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT:  (call $various-params-yes
 ;; NOMNL-NEXT:   (call $get_null_{i32})
 ;; NOMNL-NEXT:   (i32.const 1)
 ;; NOMNL-NEXT:   (call $get_null_{i32_i64})
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT: )
 (func $call-various-params-yes
  ;; The first argument gets {i32} and {i32}; the second {i32} and {i32_i64};
  ;; both of those pairs can be optimized to {i32}.
  ;; There is also an i32 in the middle, which should not confuse us.
  (call $various-params-yes
   (call $get_null_{i32})
   (i32.const 0)
   (call $get_null_{i32})
  )
  (call $various-params-yes
   (call $get_null_{i32})
   (i32.const 1)
   (call $get_null_{i32_i64})
  )
 )
 ;; This function is called in ways that *do* allow us to alter the types of
 ;; its parameters (see last function).
 ;; CHECK:      (func $various-params-yes (param $x (ref null ${i32})) (param $i i32) (param $y (ref null ${i32}))
 ;; CHECK-NEXT:  (drop
 ;; CHECK-NEXT:   (local.get $x)
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT:  (drop
 ;; CHECK-NEXT:   (local.get $i)
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT:  (drop
 ;; CHECK-NEXT:   (local.get $y)
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT: )
 ;; NOMNL:      (func $various-params-yes (type $ref?|${i32}|_i32_ref?|${i32}|_=>_none) (param $x (ref null ${i32})) (param $i i32) (param $y (ref null ${i32}))
 ;; NOMNL-NEXT:  (drop
 ;; NOMNL-NEXT:   (local.get $x)
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT:  (drop
 ;; NOMNL-NEXT:   (local.get $i)
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT:  (drop
 ;; NOMNL-NEXT:   (local.get $y)
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT: )
 (func $various-params-yes (param $x (ref null ${})) (param $i i32) (param $y (ref null ${}))
  ;; "Use" the locals to avoid other optimizations kicking in.
  (drop (local.get $x))
  (drop (local.get $i))
  (drop (local.get $y))
 )

 ;; CHECK:      (func $call-various-params-set
 ;; CHECK-NEXT:  (call $various-params-set
 ;; CHECK-NEXT:   (call $get_null_{i32})
 ;; CHECK-NEXT:   (call $get_null_{i32})
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT:  (call $various-params-set
 ;; CHECK-NEXT:   (call $get_null_{i32})
 ;; CHECK-NEXT:   (call $get_null_{i32_i64})
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT: )
 ;; NOMNL:      (func $call-various-params-set (type $none_=>_none)
 ;; NOMNL-NEXT:  (call $various-params-set
 ;; NOMNL-NEXT:   (call $get_null_{i32})
 ;; NOMNL-NEXT:   (call $get_null_{i32})
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT:  (call $various-params-set
 ;; NOMNL-NEXT:   (call $get_null_{i32})
 ;; NOMNL-NEXT:   (call $get_null_{i32_i64})
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT: )
 (func $call-various-params-set
  ;; The first argument gets {i32} and {i32}; the second {i32} and {i32_i64;
  ;; both of those pairs can be optimized to {i32}
  (call $various-params-set
   (call $get_null_{i32})
   (call $get_null_{i32})
  )
  (call $various-params-set
   (call $get_null_{i32})
   (call $get_null_{i32_i64})
  )
 )
 ;; This function is called in ways that *do* allow us to alter the types of
 ;; its parameters (see last function), however, we reuse the parameters by
 ;; writing to them, which causes problems in one case.
 ;; CHECK:      (func $various-params-set (param $x (ref null ${i32})) (param $y (ref null ${i32}))
 ;; CHECK-NEXT:  (local $2 (ref null ${}))
 ;; CHECK-NEXT:  (local.set $2
 ;; CHECK-NEXT:   (local.get $x)
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT:  (block
 ;; CHECK-NEXT:   (drop
 ;; CHECK-NEXT:    (local.get $2)
 ;; CHECK-NEXT:   )
 ;; CHECK-NEXT:   (drop
 ;; CHECK-NEXT:    (local.get $y)
 ;; CHECK-NEXT:   )
 ;; CHECK-NEXT:   (local.set $2
 ;; CHECK-NEXT:    (struct.new_default ${})
 ;; CHECK-NEXT:   )
 ;; CHECK-NEXT:   (drop
 ;; CHECK-NEXT:    (local.get $2)
 ;; CHECK-NEXT:   )
 ;; CHECK-NEXT:   (local.set $y
 ;; CHECK-NEXT:    (call $get_null_{i32_i64})
 ;; CHECK-NEXT:   )
 ;; CHECK-NEXT:   (drop
 ;; CHECK-NEXT:    (local.get $y)
 ;; CHECK-NEXT:   )
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT: )
 ;; NOMNL:      (func $various-params-set (type $ref?|${i32}|_ref?|${i32}|_=>_none) (param $x (ref null ${i32})) (param $y (ref null ${i32}))
 ;; NOMNL-NEXT:  (local $2 (ref null ${}))
 ;; NOMNL-NEXT:  (local.set $2
 ;; NOMNL-NEXT:   (local.get $x)
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT:  (block
 ;; NOMNL-NEXT:   (drop
 ;; NOMNL-NEXT:    (local.get $2)
 ;; NOMNL-NEXT:   )
 ;; NOMNL-NEXT:   (drop
 ;; NOMNL-NEXT:    (local.get $y)
 ;; NOMNL-NEXT:   )
 ;; NOMNL-NEXT:   (local.set $2
 ;; NOMNL-NEXT:    (struct.new_default ${})
 ;; NOMNL-NEXT:   )
 ;; NOMNL-NEXT:   (drop
 ;; NOMNL-NEXT:    (local.get $2)
 ;; NOMNL-NEXT:   )
 ;; NOMNL-NEXT:   (local.set $y
 ;; NOMNL-NEXT:    (call $get_null_{i32_i64})
 ;; NOMNL-NEXT:   )
 ;; NOMNL-NEXT:   (drop
 ;; NOMNL-NEXT:    (local.get $y)
 ;; NOMNL-NEXT:   )
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT: )
 (func $various-params-set (param $x (ref null ${})) (param $y (ref null ${}))
  ;; "Use" the locals to avoid other optimizations kicking in.
  (drop (local.get $x))
  (drop (local.get $y))
  ;; Write to $x a value that will not fit in the refined type, which will
  ;; force us to do a fixup: the param will get the new type, and a new local
  ;; will stay at the old type, and we will use that local throughout the
  ;; function.
  (local.set $x (struct.new ${}))
  (drop
   (local.get $x)
  )
  ;; Write to $y in a way that does not cause any issue, and we should not do
  ;; any fixup while we refine the type.
  (local.set $y (call $get_null_{i32_i64}))
  (drop
   (local.get $y)
  )
 )

 ;; CHECK:      (func $call-various-params-tee
 ;; CHECK-NEXT:  (call $various-params-tee
 ;; CHECK-NEXT:   (call $get_null_{i32})
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT: )
 ;; NOMNL:      (func $call-various-params-tee (type $none_=>_none)
 ;; NOMNL-NEXT:  (call $various-params-tee
 ;; NOMNL-NEXT:   (call $get_null_{i32})
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT: )
 (func $call-various-params-tee
  ;; The argument gets {i32}, which allows us to refine.
  (call $various-params-tee
   (call $get_null_{i32})
  )
 )
 ;; CHECK:      (func $various-params-tee (param $x (ref null ${i32}))
 ;; CHECK-NEXT:  (drop
 ;; CHECK-NEXT:   (local.get $x)
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT:  (drop
 ;; CHECK-NEXT:   (block (result (ref null ${i32}))
 ;; CHECK-NEXT:    (local.tee $x
 ;; CHECK-NEXT:     (call $get_null_{i32_i64})
 ;; CHECK-NEXT:    )
 ;; CHECK-NEXT:   )
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT: )
 ;; NOMNL:      (func $various-params-tee (type $ref?|${i32}|_=>_none) (param $x (ref null ${i32}))
 ;; NOMNL-NEXT:  (drop
 ;; NOMNL-NEXT:   (local.get $x)
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT:  (drop
 ;; NOMNL-NEXT:   (block (result (ref null ${i32}))
 ;; NOMNL-NEXT:    (local.tee $x
 ;; NOMNL-NEXT:     (call $get_null_{i32_i64})
 ;; NOMNL-NEXT:    )
 ;; NOMNL-NEXT:   )
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT: )
 (func $various-params-tee (param $x (ref null ${}))
  ;; "Use" the locals to avoid other optimizations kicking in.
  (drop (local.get $x))
  ;; Write to $x in a way that allows us to make the type more specific. We
  ;; must also update the type of the tee (if we do not, a validation error
  ;; would occur), and that will also cause the block's type to update as well.
  (drop
   (block (result (ref null ${}))
    (local.tee $x (call $get_null_{i32_i64}))
   )
  )
 )

 ;; CHECK:      (func $call-various-params-null
 ;; CHECK-NEXT:  (call $various-params-null
 ;; CHECK-NEXT:   (ref.as_non_null
 ;; CHECK-NEXT:    (ref.null none)
 ;; CHECK-NEXT:   )
 ;; CHECK-NEXT:   (call $get_null_{i32})
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT:  (call $various-params-null
 ;; CHECK-NEXT:   (ref.as_non_null
 ;; CHECK-NEXT:    (ref.null none)
 ;; CHECK-NEXT:   )
 ;; CHECK-NEXT:   (ref.as_non_null
 ;; CHECK-NEXT:    (ref.null none)
 ;; CHECK-NEXT:   )
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT: )
 ;; NOMNL:      (func $call-various-params-null (type $none_=>_none)
 ;; NOMNL-NEXT:  (call $various-params-null
 ;; NOMNL-NEXT:   (ref.as_non_null
 ;; NOMNL-NEXT:    (ref.null none)
 ;; NOMNL-NEXT:   )
 ;; NOMNL-NEXT:   (call $get_null_{i32})
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT:  (call $various-params-null
 ;; NOMNL-NEXT:   (ref.as_non_null
 ;; NOMNL-NEXT:    (ref.null none)
 ;; NOMNL-NEXT:   )
 ;; NOMNL-NEXT:   (ref.as_non_null
 ;; NOMNL-NEXT:    (ref.null none)
 ;; NOMNL-NEXT:   )
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT: )
 (func $call-various-params-null
  ;; The first argument gets non-null values, allowing us to refine it. The
  ;; second gets only one.
  (call $various-params-null
   (ref.as_non_null (ref.null ${i32}))
   (call $get_null_{i32})
  )
  (call $various-params-null
   (ref.as_non_null (ref.null ${i32}))
   (ref.as_non_null (ref.null ${i32}))
  )
 )
 ;; This function is called in ways that allow us to make the first parameter
 ;; non-nullable.
 ;; CHECK:      (func $various-params-null (param $x (ref none)) (param $y (ref null ${i32}))
 ;; CHECK-NEXT:  (local $temp i32)
 ;; CHECK-NEXT:  (drop
 ;; CHECK-NEXT:   (local.get $x)
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT:  (drop
 ;; CHECK-NEXT:   (local.get $y)
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT:  (local.set $temp
 ;; CHECK-NEXT:   (local.get $temp)
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT: )
 ;; NOMNL:      (func $various-params-null (type $ref|none|_ref?|${i32}|_=>_none) (param $x (ref none)) (param $y (ref null ${i32}))
 ;; NOMNL-NEXT:  (local $temp i32)
 ;; NOMNL-NEXT:  (drop
 ;; NOMNL-NEXT:   (local.get $x)
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT:  (drop
 ;; NOMNL-NEXT:   (local.get $y)
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT:  (local.set $temp
 ;; NOMNL-NEXT:   (local.get $temp)
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT: )
 (func $various-params-null (param $x (ref null ${})) (param $y (ref null ${}))
  (local $temp i32)
  ;; "Use" the locals to avoid other optimizations kicking in.
  (drop (local.get $x))
  (drop (local.get $y))
  ;; Use a local in this function as well, which should be ignored by this pass
  ;; (when we scan and update all local.gets and sets, we should only do so on
  ;; parameters, and not vars - and we can crash if we scan/update things we
  ;; should not).
  (local.set $temp (local.get $temp))
 )

 ;; CHECK:      (func $call-various-params-middle
 ;; CHECK-NEXT:  (call $various-params-middle
 ;; CHECK-NEXT:   (call $get_null_{i32_i64})
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT:  (call $various-params-middle
 ;; CHECK-NEXT:   (call $get_null_{i32_f32})
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT: )
 ;; NOMNL:      (func $call-various-params-middle (type $none_=>_none)
 ;; NOMNL-NEXT:  (call $various-params-middle
 ;; NOMNL-NEXT:   (call $get_null_{i32_i64})
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT:  (call $various-params-middle
 ;; NOMNL-NEXT:   (call $get_null_{i32_f32})
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT: )
 (func $call-various-params-middle
  ;; The argument gets {i32_i64} and {i32_f32}. This allows us to refine from
  ;; {} to {i32}, a type "in the middle".
  (call $various-params-middle
   (call $get_null_{i32_i64})
  )
  (call $various-params-middle
   (call $get_null_{i32_f32})
  )
 )
 ;; CHECK:      (func $various-params-middle (param $x (ref null ${i32}))
 ;; CHECK-NEXT:  (drop
 ;; CHECK-NEXT:   (local.get $x)
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT: )
 ;; NOMNL:      (func $various-params-middle (type $ref?|${i32}|_=>_none) (param $x (ref null ${i32}))
 ;; NOMNL-NEXT:  (drop
 ;; NOMNL-NEXT:   (local.get $x)
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT: )
 (func $various-params-middle (param $x (ref null ${}))
  ;; "Use" the local to avoid other optimizations kicking in.
  (drop (local.get $x))
 )

 ;; CHECK:      (func $unused-and-refinable
 ;; CHECK-NEXT:  (local $0 dataref)
 ;; CHECK-NEXT:  (nop)
 ;; CHECK-NEXT: )
 ;; NOMNL:      (func $unused-and-refinable (type $none_=>_none)
 ;; NOMNL-NEXT:  (local $0 dataref)
 ;; NOMNL-NEXT:  (nop)
 ;; NOMNL-NEXT: )
 (func $unused-and-refinable (param $0 dataref)
  ;; This function does not use $0. It is called with ${}, so it is also
  ;; a parameter whose type we can refine. Do not do both operations: instead,
  ;; just remove it because it is ignored, without altering the type (handling
  ;; both operations would introduce some corner cases, and it just isn't worth
  ;; handling them if the param is completely unused anyhow). We should see in
  ;; the test output that the local $0 (the unused param) becomes a local
  ;; because it is unused, and that local does *not* have its type refined to
  ;; ${} (it will however be changed to be nullable, which it must be as a
  ;; local).
 )

 ;; CHECK:      (func $call-unused-and-refinable
 ;; CHECK-NEXT:  (call $unused-and-refinable)
 ;; CHECK-NEXT: )
 ;; NOMNL:      (func $call-unused-and-refinable (type $none_=>_none)
 ;; NOMNL-NEXT:  (call $unused-and-refinable)
 ;; NOMNL-NEXT: )
 (func $call-unused-and-refinable
  (call $unused-and-refinable
   (struct.new_default ${})
  )
 )

 ;; CHECK:      (func $non-nullable-fixup (param $0 (ref ${}))
 ;; CHECK-NEXT:  (local $1 dataref)
 ;; CHECK-NEXT:  (local.set $1
 ;; CHECK-NEXT:   (local.get $0)
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT:  (local.set $1
 ;; CHECK-NEXT:   (local.get $1)
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT: )
 ;; NOMNL:      (func $non-nullable-fixup (type $ref|${}|_=>_none) (param $0 (ref ${}))
 ;; NOMNL-NEXT:  (local $1 dataref)
 ;; NOMNL-NEXT:  (local.set $1
 ;; NOMNL-NEXT:   (local.get $0)
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT:  (local.set $1
 ;; NOMNL-NEXT:   (local.get $1)
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT: )
 (func $non-nullable-fixup (param $0 dataref)
  ;; Use the param to avoid other opts removing it, and to force us to do a
  ;; fixup when we refine the param's type. When doing so, we must handle the
  ;; fact that the new local's type is non-nullable.
  (local.set $0
   (local.get $0)
  )
 )

 ;; CHECK:      (func $call-non-nullable-fixup
 ;; CHECK-NEXT:  (call $non-nullable-fixup
 ;; CHECK-NEXT:   (struct.new_default ${})
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT: )
 ;; NOMNL:      (func $call-non-nullable-fixup (type $none_=>_none)
 ;; NOMNL-NEXT:  (call $non-nullable-fixup
 ;; NOMNL-NEXT:   (struct.new_default ${})
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT: )
 (func $call-non-nullable-fixup
  (call $non-nullable-fixup
   (struct.new_default ${})
  )
 )

 ;; CHECK:      (func $call-update-null
 ;; CHECK-NEXT:  (call $update-null
 ;; CHECK-NEXT:   (ref.null none)
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT:  (call $update-null
 ;; CHECK-NEXT:   (struct.new_default ${})
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT: )
 ;; NOMNL:      (func $call-update-null (type $none_=>_none)
 ;; NOMNL-NEXT:  (call $update-null
 ;; NOMNL-NEXT:   (ref.null none)
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT:  (call $update-null
 ;; NOMNL-NEXT:   (struct.new_default ${})
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT: )
 (func $call-update-null
  ;; Call a function with one of the parameters a null of a type that we can
  ;; update in order to get a better LUB.
  (call $update-null
   (ref.null any)
  )
  (call $update-null
   (struct.new_default ${})
  )
 )

 ;; CHECK:      (func $update-null (param $x (ref null ${}))
 ;; CHECK-NEXT:  (drop
 ;; CHECK-NEXT:   (local.get $x)
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT: )
 ;; NOMNL:      (func $update-null (type $ref?|${}|_=>_none) (param $x (ref null ${}))
 ;; NOMNL-NEXT:  (drop
 ;; NOMNL-NEXT:   (local.get $x)
 ;; NOMNL-NEXT:  )
 ;; NOMNL-NEXT: )
 (func $update-null (param $x (ref null any))
  ;; "Use" the param to avoid other optimizations kicking in. We should only
  ;; see the type of the param refined to a null ${} after updating the null
  ;; in the caller.
  (drop (local.get $x))
 )

 ;; CHECK:      (func $get_null_{i32} (result (ref null ${i32}))
 ;; CHECK-NEXT:  (ref.null none)
 ;; CHECK-NEXT: )
 ;; NOMNL:      (func $get_null_{i32} (type $none_=>_ref?|${i32}|) (result (ref null ${i32}))
 ;; NOMNL-NEXT:  (ref.null none)
 ;; NOMNL-NEXT: )
 (func $get_null_{i32} (result (ref null ${i32}))
  ;; Helper function that returns a null value of ${i32}. We use this instead of
  ;; a direct ref.null because those can be rewritten by LUBFinder.
  (ref.null ${i32})
 )

 ;; CHECK:      (func $get_null_{i32_i64} (result (ref null ${i32_i64}))
 ;; CHECK-NEXT:  (ref.null none)
 ;; CHECK-NEXT: )
 ;; NOMNL:      (func $get_null_{i32_i64} (type $none_=>_ref?|${i32_i64}|) (result (ref null ${i32_i64}))
 ;; NOMNL-NEXT:  (ref.null none)
 ;; NOMNL-NEXT: )
 (func $get_null_{i32_i64} (result (ref null ${i32_i64}))
  (ref.null ${i32_i64})
 )

 ;; CHECK:      (func $get_null_{i32_f32} (result (ref null ${i32_f32}))
 ;; CHECK-NEXT:  (ref.null none)
 ;; CHECK-NEXT: )
 ;; NOMNL:      (func $get_null_{i32_f32} (type $none_=>_ref?|${i32_f32}|) (result (ref null ${i32_f32}))
 ;; NOMNL-NEXT:  (ref.null none)
 ;; NOMNL-NEXT: )
 (func $get_null_{i32_f32} (result (ref null ${i32_f32}))
  (ref.null ${i32_f32})
 )
)