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
|
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals
; RUN: opt < %s -passes=simplifycfg -switch-to-lookup=true -S | FileCheck %s
target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:32:32-n8:16:32"
target triple = "i386-pc-linux-gnu"
; A dense switch with a reachable default case should be optimized into a lookup table with a bounds check
;.
; CHECK: @switch.table.reachable_default_dense_0to31 = private unnamed_addr constant [32 x i32] [i32 0, i32 7, i32 6, i32 5, i32 4, i32 3, i32 2, i32 1, i32 0, i32 7, i32 6, i32 5, i32 4, i32 3, i32 2, i32 1, i32 0, i32 7, i32 6, i32 5, i32 4, i32 3, i32 2, i32 1, i32 0, i32 7, i32 6, i32 5, i32 4, i32 3, i32 2, i32 1], align 4
; CHECK: @switch.table.unreachable_default_dense_0to31 = private unnamed_addr constant [32 x i32] [i32 0, i32 7, i32 6, i32 5, i32 4, i32 3, i32 2, i32 1, i32 0, i32 7, i32 6, i32 5, i32 4, i32 3, i32 2, i32 1, i32 0, i32 7, i32 6, i32 5, i32 4, i32 3, i32 2, i32 1, i32 0, i32 7, i32 6, i32 5, i32 4, i32 3, i32 2, i32 1], align 4
; CHECK: @switch.table.reachable_default_holes_0to31 = private unnamed_addr constant [32 x i32] [i32 0, i32 7, i32 6, i32 0, i32 4, i32 3, i32 2, i32 1, i32 0, i32 7, i32 6, i32 5, i32 4, i32 0, i32 2, i32 1, i32 0, i32 7, i32 0, i32 5, i32 4, i32 3, i32 2, i32 0, i32 0, i32 7, i32 6, i32 5, i32 0, i32 3, i32 2, i32 1], align 4
; CHECK: @switch.table.unreachable_default_holes_0to31 = private unnamed_addr constant [32 x i32] [i32 0, i32 7, i32 6, i32 0, i32 4, i32 3, i32 2, i32 1, i32 0, i32 7, i32 6, i32 5, i32 4, i32 0, i32 2, i32 1, i32 0, i32 7, i32 0, i32 5, i32 4, i32 3, i32 2, i32 0, i32 0, i32 7, i32 6, i32 5, i32 0, i32 3, i32 2, i32 1], align 4
; CHECK: @switch.table.reachable_default_dense_0to32 = private unnamed_addr constant [33 x i32] [i32 0, i32 7, i32 6, i32 5, i32 4, i32 3, i32 2, i32 1, i32 0, i32 7, i32 6, i32 5, i32 4, i32 3, i32 2, i32 1, i32 0, i32 7, i32 6, i32 5, i32 4, i32 3, i32 2, i32 1, i32 0, i32 7, i32 6, i32 5, i32 4, i32 3, i32 2, i32 1, i32 0], align 4
; CHECK: @switch.table.unreachable_default_dense_0to32 = private unnamed_addr constant [33 x i32] [i32 0, i32 7, i32 6, i32 5, i32 4, i32 3, i32 2, i32 1, i32 0, i32 7, i32 6, i32 5, i32 4, i32 3, i32 2, i32 1, i32 0, i32 7, i32 6, i32 5, i32 4, i32 3, i32 2, i32 1, i32 0, i32 7, i32 6, i32 5, i32 4, i32 3, i32 2, i32 1, i32 0], align 4
; CHECK: @switch.table.unreachable_default_holes_0to32 = private unnamed_addr constant [33 x i32] [i32 0, i32 7, i32 6, i32 0, i32 4, i32 3, i32 2, i32 1, i32 0, i32 7, i32 6, i32 5, i32 4, i32 0, i32 2, i32 1, i32 0, i32 7, i32 0, i32 5, i32 4, i32 3, i32 2, i32 0, i32 0, i32 7, i32 6, i32 5, i32 0, i32 3, i32 2, i32 1, i32 0], align 4
;.
define i32 @reachable_default_dense_0to31(i32 %x, i32 %y) {
; CHECK-LABEL: @reachable_default_dense_0to31(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = icmp ult i32 [[X:%.*]], 32
; CHECK-NEXT: br i1 [[TMP0]], label [[SWITCH_LOOKUP:%.*]], label [[RETURN:%.*]]
; CHECK: switch.lookup:
; CHECK-NEXT: [[SWITCH_GEP:%.*]] = getelementptr inbounds [32 x i32], ptr @switch.table.reachable_default_dense_0to31, i32 0, i32 [[X]]
; CHECK-NEXT: [[SWITCH_LOAD:%.*]] = load i32, ptr [[SWITCH_GEP]], align 4
; CHECK-NEXT: br label [[RETURN]]
; CHECK: return:
; CHECK-NEXT: [[RES:%.*]] = phi i32 [ [[SWITCH_LOAD]], [[SWITCH_LOOKUP]] ], [ [[Y:%.*]], [[ENTRY:%.*]] ]
; CHECK-NEXT: ret i32 [[RES]]
;
entry:
switch i32 %x, label %sw.default [
i32 0, label %bb0
i32 1, label %bb7
i32 2, label %bb6
i32 3, label %bb5
i32 4, label %bb4
i32 5, label %bb3
i32 6, label %bb2
i32 7, label %bb1
i32 8, label %bb0
i32 9, label %bb7
i32 10, label %bb6
i32 11, label %bb5
i32 12, label %bb4
i32 13, label %bb3
i32 14, label %bb2
i32 15, label %bb1
i32 16, label %bb0
i32 17, label %bb7
i32 18, label %bb6
i32 19, label %bb5
i32 20, label %bb4
i32 21, label %bb3
i32 22, label %bb2
i32 23, label %bb1
i32 24, label %bb0
i32 25, label %bb7
i32 26, label %bb6
i32 27, label %bb5
i32 28, label %bb4
i32 29, label %bb3
i32 30, label %bb2
i32 31, label %bb1
]
sw.default: br label %return
bb0: br label %return
bb1: br label %return
bb2: br label %return
bb3: br label %return
bb4: br label %return
bb5: br label %return
bb6: br label %return
bb7: br label %return
return:
%res = phi i32 [ %y, %sw.default ], [ 0, %bb0 ], [ 1, %bb1 ], [ 2, %bb2 ], [ 3, %bb3 ], [ 4, %bb4 ], [ 5, %bb5 ], [ 6, %bb6 ], [ 7, %bb7 ]
ret i32 %res
}
; A dense switch with an unreachable default case should be optimized into a lookup table without bounds checks
define i32 @unreachable_default_dense_0to31(i32 %x, i32 %y) {
; CHECK-LABEL: @unreachable_default_dense_0to31(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[SWITCH_GEP:%.*]] = getelementptr inbounds [32 x i32], ptr @switch.table.unreachable_default_dense_0to31, i32 0, i32 [[X:%.*]]
; CHECK-NEXT: [[SWITCH_LOAD:%.*]] = load i32, ptr [[SWITCH_GEP]], align 4
; CHECK-NEXT: ret i32 [[SWITCH_LOAD]]
;
entry:
switch i32 %x, label %sw.default [
i32 0, label %bb0
i32 1, label %bb7
i32 2, label %bb6
i32 3, label %bb5
i32 4, label %bb4
i32 5, label %bb3
i32 6, label %bb2
i32 7, label %bb1
i32 8, label %bb0
i32 9, label %bb7
i32 10, label %bb6
i32 11, label %bb5
i32 12, label %bb4
i32 13, label %bb3
i32 14, label %bb2
i32 15, label %bb1
i32 16, label %bb0
i32 17, label %bb7
i32 18, label %bb6
i32 19, label %bb5
i32 20, label %bb4
i32 21, label %bb3
i32 22, label %bb2
i32 23, label %bb1
i32 24, label %bb0
i32 25, label %bb7
i32 26, label %bb6
i32 27, label %bb5
i32 28, label %bb4
i32 29, label %bb3
i32 30, label %bb2
i32 31, label %bb1
]
sw.default: unreachable
bb0: br label %return
bb1: br label %return
bb2: br label %return
bb3: br label %return
bb4: br label %return
bb5: br label %return
bb6: br label %return
bb7: br label %return
return:
%res = phi i32 [ 0, %bb0 ], [ 1, %bb1 ], [ 2, %bb2 ], [ 3, %bb3 ], [ 4, %bb4 ], [ 5, %bb5 ], [ 6, %bb6 ], [ 7, %bb7 ]
ret i32 %res
}
; A sparse switch with a reachable default case should be optimized into a lookup table with a bounds check and a mask
define i32 @reachable_default_holes_0to31(i32 %x, i32 %y) {
; CHECK-LABEL: @reachable_default_holes_0to31(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = icmp ult i32 [[X:%.*]], 32
; CHECK-NEXT: br i1 [[TMP0]], label [[SWITCH_HOLE_CHECK:%.*]], label [[RETURN:%.*]]
; CHECK: switch.hole_check:
; CHECK-NEXT: [[SWITCH_SHIFTED:%.*]] = lshr i32 -277094665, [[X]]
; CHECK-NEXT: [[SWITCH_LOBIT:%.*]] = trunc i32 [[SWITCH_SHIFTED]] to i1
; CHECK-NEXT: br i1 [[SWITCH_LOBIT]], label [[SWITCH_LOOKUP:%.*]], label [[RETURN]]
; CHECK: switch.lookup:
; CHECK-NEXT: [[SWITCH_GEP:%.*]] = getelementptr inbounds [32 x i32], ptr @switch.table.reachable_default_holes_0to31, i32 0, i32 [[X]]
; CHECK-NEXT: [[SWITCH_LOAD:%.*]] = load i32, ptr [[SWITCH_GEP]], align 4
; CHECK-NEXT: br label [[RETURN]]
; CHECK: return:
; CHECK-NEXT: [[RES:%.*]] = phi i32 [ [[SWITCH_LOAD]], [[SWITCH_LOOKUP]] ], [ [[Y:%.*]], [[SWITCH_HOLE_CHECK]] ], [ [[Y]], [[ENTRY:%.*]] ]
; CHECK-NEXT: ret i32 [[RES]]
;
entry:
switch i32 %x, label %sw.default [
i32 0, label %bb0
i32 1, label %bb7
i32 2, label %bb6
i32 4, label %bb4
i32 5, label %bb3
i32 6, label %bb2
i32 7, label %bb1
i32 9, label %bb7
i32 10, label %bb6
i32 11, label %bb5
i32 12, label %bb4
i32 14, label %bb2
i32 15, label %bb1
i32 16, label %bb0
i32 17, label %bb7
i32 19, label %bb5
i32 20, label %bb4
i32 21, label %bb3
i32 22, label %bb2
i32 24, label %bb0
i32 25, label %bb7
i32 26, label %bb6
i32 27, label %bb5
i32 29, label %bb3
i32 30, label %bb2
i32 31, label %bb1
]
sw.default: br label %return
bb0: br label %return
bb1: br label %return
bb2: br label %return
bb3: br label %return
bb4: br label %return
bb5: br label %return
bb6: br label %return
bb7: br label %return
return:
%res = phi i32 [ %y, %sw.default ], [ 0, %bb0 ], [ 1, %bb1 ], [ 2, %bb2 ], [ 3, %bb3 ], [ 4, %bb4 ], [ 5, %bb5 ], [ 6, %bb6 ], [ 7, %bb7 ]
ret i32 %res
}
; A sparse switch with an unreachable default case should be optimized into a lookup table without bounds checks
define i32 @unreachable_default_holes_0to31(i32 %x, i32 %y) {
; CHECK-LABEL: @unreachable_default_holes_0to31(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[SWITCH_GEP:%.*]] = getelementptr inbounds [32 x i32], ptr @switch.table.unreachable_default_holes_0to31, i32 0, i32 [[X:%.*]]
; CHECK-NEXT: [[SWITCH_LOAD:%.*]] = load i32, ptr [[SWITCH_GEP]], align 4
; CHECK-NEXT: ret i32 [[SWITCH_LOAD]]
;
entry:
switch i32 %x, label %sw.default [
i32 0, label %bb0
i32 1, label %bb7
i32 2, label %bb6
i32 4, label %bb4
i32 5, label %bb3
i32 6, label %bb2
i32 7, label %bb1
i32 9, label %bb7
i32 10, label %bb6
i32 11, label %bb5
i32 12, label %bb4
i32 14, label %bb2
i32 15, label %bb1
i32 16, label %bb0
i32 17, label %bb7
i32 19, label %bb5
i32 20, label %bb4
i32 21, label %bb3
i32 22, label %bb2
i32 24, label %bb0
i32 25, label %bb7
i32 26, label %bb6
i32 27, label %bb5
i32 29, label %bb3
i32 30, label %bb2
i32 31, label %bb1
]
sw.default: unreachable
bb0: br label %return
bb1: br label %return
bb2: br label %return
bb3: br label %return
bb4: br label %return
bb5: br label %return
bb6: br label %return
bb7: br label %return
return:
%res = phi i32 [ 0, %bb0 ], [ 1, %bb1 ], [ 2, %bb2 ], [ 3, %bb3 ], [ 4, %bb4 ], [ 5, %bb5 ], [ 6, %bb6 ], [ 7, %bb7 ]
ret i32 %res
}
; A dense switch with a reachable default case should be optimized into a lookup table with a bounds check
define i32 @reachable_default_dense_0to32(i32 %x, i32 %y) {
; CHECK-LABEL: @reachable_default_dense_0to32(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = icmp ult i32 [[X:%.*]], 33
; CHECK-NEXT: br i1 [[TMP0]], label [[SWITCH_LOOKUP:%.*]], label [[RETURN:%.*]]
; CHECK: switch.lookup:
; CHECK-NEXT: [[SWITCH_GEP:%.*]] = getelementptr inbounds [33 x i32], ptr @switch.table.reachable_default_dense_0to32, i32 0, i32 [[X]]
; CHECK-NEXT: [[SWITCH_LOAD:%.*]] = load i32, ptr [[SWITCH_GEP]], align 4
; CHECK-NEXT: br label [[RETURN]]
; CHECK: return:
; CHECK-NEXT: [[RES:%.*]] = phi i32 [ [[SWITCH_LOAD]], [[SWITCH_LOOKUP]] ], [ [[Y:%.*]], [[ENTRY:%.*]] ]
; CHECK-NEXT: ret i32 [[RES]]
;
entry:
switch i32 %x, label %sw.default [
i32 0, label %bb0
i32 1, label %bb7
i32 2, label %bb6
i32 3, label %bb5
i32 4, label %bb4
i32 5, label %bb3
i32 6, label %bb2
i32 7, label %bb1
i32 8, label %bb0
i32 9, label %bb7
i32 10, label %bb6
i32 11, label %bb5
i32 12, label %bb4
i32 13, label %bb3
i32 14, label %bb2
i32 15, label %bb1
i32 16, label %bb0
i32 17, label %bb7
i32 18, label %bb6
i32 19, label %bb5
i32 20, label %bb4
i32 21, label %bb3
i32 22, label %bb2
i32 23, label %bb1
i32 24, label %bb0
i32 25, label %bb7
i32 26, label %bb6
i32 27, label %bb5
i32 28, label %bb4
i32 29, label %bb3
i32 30, label %bb2
i32 31, label %bb1
i32 32, label %bb0
]
sw.default: br label %return
bb0: br label %return
bb1: br label %return
bb2: br label %return
bb3: br label %return
bb4: br label %return
bb5: br label %return
bb6: br label %return
bb7: br label %return
return:
%res = phi i32 [ %y, %sw.default ], [ 0, %bb0 ], [ 1, %bb1 ], [ 2, %bb2 ], [ 3, %bb3 ], [ 4, %bb4 ], [ 5, %bb5 ], [ 6, %bb6 ], [ 7, %bb7 ]
ret i32 %res
}
; A dense switch with an unreachable default case should be optimized into a lookup table without bounds checks
define i32 @unreachable_default_dense_0to32(i32 %x, i32 %y) {
; CHECK-LABEL: @unreachable_default_dense_0to32(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[SWITCH_GEP:%.*]] = getelementptr inbounds [33 x i32], ptr @switch.table.unreachable_default_dense_0to32, i32 0, i32 [[X:%.*]]
; CHECK-NEXT: [[SWITCH_LOAD:%.*]] = load i32, ptr [[SWITCH_GEP]], align 4
; CHECK-NEXT: ret i32 [[SWITCH_LOAD]]
;
entry:
switch i32 %x, label %sw.default [
i32 0, label %bb0
i32 1, label %bb7
i32 2, label %bb6
i32 3, label %bb5
i32 4, label %bb4
i32 5, label %bb3
i32 6, label %bb2
i32 7, label %bb1
i32 8, label %bb0
i32 9, label %bb7
i32 10, label %bb6
i32 11, label %bb5
i32 12, label %bb4
i32 13, label %bb3
i32 14, label %bb2
i32 15, label %bb1
i32 16, label %bb0
i32 17, label %bb7
i32 18, label %bb6
i32 19, label %bb5
i32 20, label %bb4
i32 21, label %bb3
i32 22, label %bb2
i32 23, label %bb1
i32 24, label %bb0
i32 25, label %bb7
i32 26, label %bb6
i32 27, label %bb5
i32 28, label %bb4
i32 29, label %bb3
i32 30, label %bb2
i32 31, label %bb1
i32 32, label %bb0
]
sw.default: unreachable
bb0: br label %return
bb1: br label %return
bb2: br label %return
bb3: br label %return
bb4: br label %return
bb5: br label %return
bb6: br label %return
bb7: br label %return
return:
%res = phi i32 [ 0, %bb0 ], [ 1, %bb1 ], [ 2, %bb2 ], [ 3, %bb3 ], [ 4, %bb4 ], [ 5, %bb5 ], [ 6, %bb6 ], [ 7, %bb7 ]
ret i32 %res
}
; A sparse switch with a reachable default case which would be optimized into a lookup table with a bounds check and a mask, but doesn't because
; it would require a 33-bit mask
define i32 @reachable_default_holes_0to32(i32 %x, i32 %y) {
; CHECK-LABEL: @reachable_default_holes_0to32(
; CHECK-NEXT: entry:
; CHECK-NEXT: switch i32 [[X:%.*]], label [[RETURN:%.*]] [
; CHECK-NEXT: i32 0, label [[BB0:%.*]]
; CHECK-NEXT: i32 1, label [[BB7:%.*]]
; CHECK-NEXT: i32 2, label [[BB6:%.*]]
; CHECK-NEXT: i32 4, label [[BB4:%.*]]
; CHECK-NEXT: i32 5, label [[BB3:%.*]]
; CHECK-NEXT: i32 6, label [[BB2:%.*]]
; CHECK-NEXT: i32 7, label [[BB1:%.*]]
; CHECK-NEXT: i32 9, label [[BB7]]
; CHECK-NEXT: i32 10, label [[BB6]]
; CHECK-NEXT: i32 11, label [[BB5:%.*]]
; CHECK-NEXT: i32 12, label [[BB4]]
; CHECK-NEXT: i32 14, label [[BB2]]
; CHECK-NEXT: i32 15, label [[BB1]]
; CHECK-NEXT: i32 16, label [[BB0]]
; CHECK-NEXT: i32 17, label [[BB7]]
; CHECK-NEXT: i32 19, label [[BB5]]
; CHECK-NEXT: i32 20, label [[BB4]]
; CHECK-NEXT: i32 21, label [[BB3]]
; CHECK-NEXT: i32 22, label [[BB2]]
; CHECK-NEXT: i32 24, label [[BB0]]
; CHECK-NEXT: i32 25, label [[BB7]]
; CHECK-NEXT: i32 26, label [[BB6]]
; CHECK-NEXT: i32 27, label [[BB5]]
; CHECK-NEXT: i32 29, label [[BB3]]
; CHECK-NEXT: i32 30, label [[BB2]]
; CHECK-NEXT: i32 31, label [[BB1]]
; CHECK-NEXT: i32 32, label [[BB0]]
; CHECK-NEXT: ]
; CHECK: bb0:
; CHECK-NEXT: br label [[RETURN]]
; CHECK: bb1:
; CHECK-NEXT: br label [[RETURN]]
; CHECK: bb2:
; CHECK-NEXT: br label [[RETURN]]
; CHECK: bb3:
; CHECK-NEXT: br label [[RETURN]]
; CHECK: bb4:
; CHECK-NEXT: br label [[RETURN]]
; CHECK: bb5:
; CHECK-NEXT: br label [[RETURN]]
; CHECK: bb6:
; CHECK-NEXT: br label [[RETURN]]
; CHECK: bb7:
; CHECK-NEXT: br label [[RETURN]]
; CHECK: return:
; CHECK-NEXT: [[RES:%.*]] = phi i32 [ 0, [[BB0]] ], [ 1, [[BB1]] ], [ 2, [[BB2]] ], [ 3, [[BB3]] ], [ 4, [[BB4]] ], [ 5, [[BB5]] ], [ 6, [[BB6]] ], [ 7, [[BB7]] ], [ [[Y:%.*]], [[ENTRY:%.*]] ]
; CHECK-NEXT: ret i32 [[RES]]
;
entry:
switch i32 %x, label %sw.default [
i32 0, label %bb0
i32 1, label %bb7
i32 2, label %bb6
i32 4, label %bb4
i32 5, label %bb3
i32 6, label %bb2
i32 7, label %bb1
i32 9, label %bb7
i32 10, label %bb6
i32 11, label %bb5
i32 12, label %bb4
i32 14, label %bb2
i32 15, label %bb1
i32 16, label %bb0
i32 17, label %bb7
i32 19, label %bb5
i32 20, label %bb4
i32 21, label %bb3
i32 22, label %bb2
i32 24, label %bb0
i32 25, label %bb7
i32 26, label %bb6
i32 27, label %bb5
i32 29, label %bb3
i32 30, label %bb2
i32 31, label %bb1
i32 32, label %bb0
]
sw.default: br label %return
bb0: br label %return
bb1: br label %return
bb2: br label %return
bb3: br label %return
bb4: br label %return
bb5: br label %return
bb6: br label %return
bb7: br label %return
return:
%res = phi i32 [ %y, %sw.default ], [ 0, %bb0 ], [ 1, %bb1 ], [ 2, %bb2 ], [ 3, %bb3 ], [ 4, %bb4 ], [ 5, %bb5 ], [ 6, %bb6 ], [ 7, %bb7 ]
ret i32 %res
}
; A sparse switch with an unreachable default case which can be optimized into a lookup table without bounds checks. Because the default case is
; unreachable, the fact that a 33-bit mask would be required doesn't prevent lookup table optimization.
define i32 @unreachable_default_holes_0to32(i32 %x, i32 %y) {
; CHECK-LABEL: @unreachable_default_holes_0to32(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[SWITCH_GEP:%.*]] = getelementptr inbounds [33 x i32], ptr @switch.table.unreachable_default_holes_0to32, i32 0, i32 [[X:%.*]]
; CHECK-NEXT: [[SWITCH_LOAD:%.*]] = load i32, ptr [[SWITCH_GEP]], align 4
; CHECK-NEXT: ret i32 [[SWITCH_LOAD]]
;
entry:
switch i32 %x, label %sw.default [
i32 0, label %bb0
i32 1, label %bb7
i32 2, label %bb6
i32 4, label %bb4
i32 5, label %bb3
i32 6, label %bb2
i32 7, label %bb1
i32 9, label %bb7
i32 10, label %bb6
i32 11, label %bb5
i32 12, label %bb4
i32 14, label %bb2
i32 15, label %bb1
i32 16, label %bb0
i32 17, label %bb7
i32 19, label %bb5
i32 20, label %bb4
i32 21, label %bb3
i32 22, label %bb2
i32 24, label %bb0
i32 25, label %bb7
i32 26, label %bb6
i32 27, label %bb5
i32 29, label %bb3
i32 30, label %bb2
i32 31, label %bb1
i32 32, label %bb0
]
sw.default: unreachable
bb0: br label %return
bb1: br label %return
bb2: br label %return
bb3: br label %return
bb4: br label %return
bb5: br label %return
bb6: br label %return
bb7: br label %return
return:
%res = phi i32 [ 0, %bb0 ], [ 1, %bb1 ], [ 2, %bb2 ], [ 3, %bb3 ], [ 4, %bb4 ], [ 5, %bb5 ], [ 6, %bb6 ], [ 7, %bb7 ]
ret i32 %res
}
|
