rotate.ll
24.5 KB
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
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -instcombine -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-f80:128:128"
; TODO: Canonicalize rotate by constant to funnel shift intrinsics.
; This should help cost modeling for vectorization, inlining, etc.
; If a target does not have a rotate instruction, the expansion will
; be exactly these same 3 basic ops (shl/lshr/or).
define i32 @rotl_i32_constant(i32 %x) {
; CHECK-LABEL: @rotl_i32_constant(
; CHECK-NEXT: [[SHL:%.*]] = shl i32 [[X:%.*]], 11
; CHECK-NEXT: [[SHR:%.*]] = lshr i32 [[X]], 21
; CHECK-NEXT: [[R:%.*]] = or i32 [[SHR]], [[SHL]]
; CHECK-NEXT: ret i32 [[R]]
;
%shl = shl i32 %x, 11
%shr = lshr i32 %x, 21
%r = or i32 %shr, %shl
ret i32 %r
}
define i42 @rotr_i42_constant(i42 %x) {
; CHECK-LABEL: @rotr_i42_constant(
; CHECK-NEXT: [[SHL:%.*]] = shl i42 [[X:%.*]], 31
; CHECK-NEXT: [[SHR:%.*]] = lshr i42 [[X]], 11
; CHECK-NEXT: [[R:%.*]] = or i42 [[SHR]], [[SHL]]
; CHECK-NEXT: ret i42 [[R]]
;
%shl = shl i42 %x, 31
%shr = lshr i42 %x, 11
%r = or i42 %shr, %shl
ret i42 %r
}
define i8 @rotr_i8_constant_commute(i8 %x) {
; CHECK-LABEL: @rotr_i8_constant_commute(
; CHECK-NEXT: [[SHL:%.*]] = shl i8 [[X:%.*]], 5
; CHECK-NEXT: [[SHR:%.*]] = lshr i8 [[X]], 3
; CHECK-NEXT: [[R:%.*]] = or i8 [[SHL]], [[SHR]]
; CHECK-NEXT: ret i8 [[R]]
;
%shl = shl i8 %x, 5
%shr = lshr i8 %x, 3
%r = or i8 %shl, %shr
ret i8 %r
}
define i88 @rotl_i88_constant_commute(i88 %x) {
; CHECK-LABEL: @rotl_i88_constant_commute(
; CHECK-NEXT: [[SHL:%.*]] = shl i88 [[X:%.*]], 44
; CHECK-NEXT: [[SHR:%.*]] = lshr i88 [[X]], 44
; CHECK-NEXT: [[R:%.*]] = or i88 [[SHL]], [[SHR]]
; CHECK-NEXT: ret i88 [[R]]
;
%shl = shl i88 %x, 44
%shr = lshr i88 %x, 44
%r = or i88 %shl, %shr
ret i88 %r
}
; Vector types are allowed.
define <2 x i16> @rotl_v2i16_constant_splat(<2 x i16> %x) {
; CHECK-LABEL: @rotl_v2i16_constant_splat(
; CHECK-NEXT: [[SHL:%.*]] = shl <2 x i16> [[X:%.*]], <i16 1, i16 1>
; CHECK-NEXT: [[SHR:%.*]] = lshr <2 x i16> [[X]], <i16 15, i16 15>
; CHECK-NEXT: [[R:%.*]] = or <2 x i16> [[SHL]], [[SHR]]
; CHECK-NEXT: ret <2 x i16> [[R]]
;
%shl = shl <2 x i16> %x, <i16 1, i16 1>
%shr = lshr <2 x i16> %x, <i16 15, i16 15>
%r = or <2 x i16> %shl, %shr
ret <2 x i16> %r
}
; Non-power-of-2 vector types are allowed.
define <2 x i17> @rotr_v2i17_constant_splat(<2 x i17> %x) {
; CHECK-LABEL: @rotr_v2i17_constant_splat(
; CHECK-NEXT: [[SHL:%.*]] = shl <2 x i17> [[X:%.*]], <i17 12, i17 12>
; CHECK-NEXT: [[SHR:%.*]] = lshr <2 x i17> [[X]], <i17 5, i17 5>
; CHECK-NEXT: [[R:%.*]] = or <2 x i17> [[SHR]], [[SHL]]
; CHECK-NEXT: ret <2 x i17> [[R]]
;
%shl = shl <2 x i17> %x, <i17 12, i17 12>
%shr = lshr <2 x i17> %x, <i17 5, i17 5>
%r = or <2 x i17> %shr, %shl
ret <2 x i17> %r
}
; Allow arbitrary shift constants.
define <2 x i32> @rotr_v2i32_constant_nonsplat(<2 x i32> %x) {
; CHECK-LABEL: @rotr_v2i32_constant_nonsplat(
; CHECK-NEXT: [[SHL:%.*]] = shl <2 x i32> [[X:%.*]], <i32 17, i32 19>
; CHECK-NEXT: [[SHR:%.*]] = lshr <2 x i32> [[X]], <i32 15, i32 13>
; CHECK-NEXT: [[R:%.*]] = or <2 x i32> [[SHL]], [[SHR]]
; CHECK-NEXT: ret <2 x i32> [[R]]
;
%shl = shl <2 x i32> %x, <i32 17, i32 19>
%shr = lshr <2 x i32> %x, <i32 15, i32 13>
%r = or <2 x i32> %shl, %shr
ret <2 x i32> %r
}
define <2 x i36> @rotl_v2i16_constant_nonsplat(<2 x i36> %x) {
; CHECK-LABEL: @rotl_v2i16_constant_nonsplat(
; CHECK-NEXT: [[SHL:%.*]] = shl <2 x i36> [[X:%.*]], <i36 21, i36 11>
; CHECK-NEXT: [[SHR:%.*]] = lshr <2 x i36> [[X]], <i36 15, i36 25>
; CHECK-NEXT: [[R:%.*]] = or <2 x i36> [[SHL]], [[SHR]]
; CHECK-NEXT: ret <2 x i36> [[R]]
;
%shl = shl <2 x i36> %x, <i36 21, i36 11>
%shr = lshr <2 x i36> %x, <i36 15, i36 25>
%r = or <2 x i36> %shl, %shr
ret <2 x i36> %r
}
; The most basic rotate by variable - no guards for UB due to oversized shifts.
; This cannot be canonicalized to funnel shift target-independently. The safe
; expansion includes masking for the shift amount that is not included here,
; so it could be more expensive.
define i32 @rotl_i32(i32 %x, i32 %y) {
; CHECK-LABEL: @rotl_i32(
; CHECK-NEXT: [[SUB:%.*]] = sub i32 32, [[Y:%.*]]
; CHECK-NEXT: [[SHL:%.*]] = shl i32 [[X:%.*]], [[Y]]
; CHECK-NEXT: [[SHR:%.*]] = lshr i32 [[X]], [[SUB]]
; CHECK-NEXT: [[R:%.*]] = or i32 [[SHR]], [[SHL]]
; CHECK-NEXT: ret i32 [[R]]
;
%sub = sub i32 32, %y
%shl = shl i32 %x, %y
%shr = lshr i32 %x, %sub
%r = or i32 %shr, %shl
ret i32 %r
}
; Non-power-of-2 types should follow the same reasoning. Left/right is determined by subtract.
define i37 @rotr_i37(i37 %x, i37 %y) {
; CHECK-LABEL: @rotr_i37(
; CHECK-NEXT: [[SUB:%.*]] = sub i37 37, [[Y:%.*]]
; CHECK-NEXT: [[SHL:%.*]] = shl i37 [[X:%.*]], [[SUB]]
; CHECK-NEXT: [[SHR:%.*]] = lshr i37 [[X]], [[Y]]
; CHECK-NEXT: [[R:%.*]] = or i37 [[SHR]], [[SHL]]
; CHECK-NEXT: ret i37 [[R]]
;
%sub = sub i37 37, %y
%shl = shl i37 %x, %sub
%shr = lshr i37 %x, %y
%r = or i37 %shr, %shl
ret i37 %r
}
; Commute 'or' operands.
define i8 @rotr_i8_commute(i8 %x, i8 %y) {
; CHECK-LABEL: @rotr_i8_commute(
; CHECK-NEXT: [[SUB:%.*]] = sub i8 8, [[Y:%.*]]
; CHECK-NEXT: [[SHL:%.*]] = shl i8 [[X:%.*]], [[SUB]]
; CHECK-NEXT: [[SHR:%.*]] = lshr i8 [[X]], [[Y]]
; CHECK-NEXT: [[R:%.*]] = or i8 [[SHL]], [[SHR]]
; CHECK-NEXT: ret i8 [[R]]
;
%sub = sub i8 8, %y
%shl = shl i8 %x, %sub
%shr = lshr i8 %x, %y
%r = or i8 %shl, %shr
ret i8 %r
}
; Vector types should follow the same rules.
define <4 x i32> @rotl_v4i32(<4 x i32> %x, <4 x i32> %y) {
; CHECK-LABEL: @rotl_v4i32(
; CHECK-NEXT: [[SUB:%.*]] = sub <4 x i32> <i32 32, i32 32, i32 32, i32 32>, [[Y:%.*]]
; CHECK-NEXT: [[SHL:%.*]] = shl <4 x i32> [[X:%.*]], [[Y]]
; CHECK-NEXT: [[SHR:%.*]] = lshr <4 x i32> [[X]], [[SUB]]
; CHECK-NEXT: [[R:%.*]] = or <4 x i32> [[SHL]], [[SHR]]
; CHECK-NEXT: ret <4 x i32> [[R]]
;
%sub = sub <4 x i32> <i32 32, i32 32, i32 32, i32 32>, %y
%shl = shl <4 x i32> %x, %y
%shr = lshr <4 x i32> %x, %sub
%r = or <4 x i32> %shl, %shr
ret <4 x i32> %r
}
; Non-power-of-2 vector types should follow the same rules.
define <3 x i42> @rotr_v3i42(<3 x i42> %x, <3 x i42> %y) {
; CHECK-LABEL: @rotr_v3i42(
; CHECK-NEXT: [[SUB:%.*]] = sub <3 x i42> <i42 42, i42 42, i42 42>, [[Y:%.*]]
; CHECK-NEXT: [[SHL:%.*]] = shl <3 x i42> [[X:%.*]], [[SUB]]
; CHECK-NEXT: [[SHR:%.*]] = lshr <3 x i42> [[X]], [[Y]]
; CHECK-NEXT: [[R:%.*]] = or <3 x i42> [[SHR]], [[SHL]]
; CHECK-NEXT: ret <3 x i42> [[R]]
;
%sub = sub <3 x i42> <i42 42, i42 42, i42 42>, %y
%shl = shl <3 x i42> %x, %sub
%shr = lshr <3 x i42> %x, %y
%r = or <3 x i42> %shr, %shl
ret <3 x i42> %r
}
; This is the canonical pattern for a UB-safe rotate-by-variable with power-of-2-size scalar type.
; The backend expansion of funnel shift for targets that don't have a rotate instruction should
; match the original IR, so it is always good to canonicalize to the intrinsics for this pattern.
define i32 @rotl_safe_i32(i32 %x, i32 %y) {
; CHECK-LABEL: @rotl_safe_i32(
; CHECK-NEXT: [[R:%.*]] = call i32 @llvm.fshl.i32(i32 [[X:%.*]], i32 [[X]], i32 [[Y:%.*]])
; CHECK-NEXT: ret i32 [[R]]
;
%negy = sub i32 0, %y
%ymask = and i32 %y, 31
%negymask = and i32 %negy, 31
%shl = shl i32 %x, %ymask
%shr = lshr i32 %x, %negymask
%r = or i32 %shr, %shl
ret i32 %r
}
; Extra uses don't change anything.
define i16 @rotl_safe_i16_commute_extra_use(i16 %x, i16 %y, i16* %p) {
; CHECK-LABEL: @rotl_safe_i16_commute_extra_use(
; CHECK-NEXT: [[NEGY:%.*]] = sub i16 0, [[Y:%.*]]
; CHECK-NEXT: [[NEGYMASK:%.*]] = and i16 [[NEGY]], 15
; CHECK-NEXT: store i16 [[NEGYMASK]], i16* [[P:%.*]], align 2
; CHECK-NEXT: [[R:%.*]] = call i16 @llvm.fshl.i16(i16 [[X:%.*]], i16 [[X]], i16 [[Y]])
; CHECK-NEXT: ret i16 [[R]]
;
%negy = sub i16 0, %y
%ymask = and i16 %y, 15
%negymask = and i16 %negy, 15
store i16 %negymask, i16* %p
%shl = shl i16 %x, %ymask
%shr = lshr i16 %x, %negymask
%r = or i16 %shl, %shr
ret i16 %r
}
; Left/right is determined by the negation.
define i64 @rotr_safe_i64(i64 %x, i64 %y) {
; CHECK-LABEL: @rotr_safe_i64(
; CHECK-NEXT: [[R:%.*]] = call i64 @llvm.fshr.i64(i64 [[X:%.*]], i64 [[X]], i64 [[Y:%.*]])
; CHECK-NEXT: ret i64 [[R]]
;
%negy = sub i64 0, %y
%ymask = and i64 %y, 63
%negymask = and i64 %negy, 63
%shl = shl i64 %x, %negymask
%shr = lshr i64 %x, %ymask
%r = or i64 %shr, %shl
ret i64 %r
}
; Extra uses don't change anything.
define i8 @rotr_safe_i8_commute_extra_use(i8 %x, i8 %y, i8* %p) {
; CHECK-LABEL: @rotr_safe_i8_commute_extra_use(
; CHECK-NEXT: [[NEGY:%.*]] = sub i8 0, [[Y:%.*]]
; CHECK-NEXT: [[YMASK:%.*]] = and i8 [[Y]], 7
; CHECK-NEXT: [[NEGYMASK:%.*]] = and i8 [[NEGY]], 7
; CHECK-NEXT: [[SHL:%.*]] = shl i8 [[X:%.*]], [[NEGYMASK]]
; CHECK-NEXT: [[SHR:%.*]] = lshr i8 [[X]], [[YMASK]]
; CHECK-NEXT: store i8 [[SHR]], i8* [[P:%.*]], align 1
; CHECK-NEXT: [[R:%.*]] = or i8 [[SHL]], [[SHR]]
; CHECK-NEXT: ret i8 [[R]]
;
%negy = sub i8 0, %y
%ymask = and i8 %y, 7
%negymask = and i8 %negy, 7
%shl = shl i8 %x, %negymask
%shr = lshr i8 %x, %ymask
store i8 %shr, i8* %p
%r = or i8 %shl, %shr
ret i8 %r
}
; Vectors follow the same rules.
define <2 x i32> @rotl_safe_v2i32(<2 x i32> %x, <2 x i32> %y) {
; CHECK-LABEL: @rotl_safe_v2i32(
; CHECK-NEXT: [[R:%.*]] = call <2 x i32> @llvm.fshl.v2i32(<2 x i32> [[X:%.*]], <2 x i32> [[X]], <2 x i32> [[Y:%.*]])
; CHECK-NEXT: ret <2 x i32> [[R]]
;
%negy = sub <2 x i32> zeroinitializer, %y
%ymask = and <2 x i32> %y, <i32 31, i32 31>
%negymask = and <2 x i32> %negy, <i32 31, i32 31>
%shl = shl <2 x i32> %x, %ymask
%shr = lshr <2 x i32> %x, %negymask
%r = or <2 x i32> %shr, %shl
ret <2 x i32> %r
}
; Vectors follow the same rules.
define <3 x i16> @rotr_safe_v3i16(<3 x i16> %x, <3 x i16> %y) {
; CHECK-LABEL: @rotr_safe_v3i16(
; CHECK-NEXT: [[R:%.*]] = call <3 x i16> @llvm.fshr.v3i16(<3 x i16> [[X:%.*]], <3 x i16> [[X]], <3 x i16> [[Y:%.*]])
; CHECK-NEXT: ret <3 x i16> [[R]]
;
%negy = sub <3 x i16> zeroinitializer, %y
%ymask = and <3 x i16> %y, <i16 15, i16 15, i16 15>
%negymask = and <3 x i16> %negy, <i16 15, i16 15, i16 15>
%shl = shl <3 x i16> %x, %negymask
%shr = lshr <3 x i16> %x, %ymask
%r = or <3 x i16> %shr, %shl
ret <3 x i16> %r
}
; These are optionally UB-free rotate left/right patterns that are narrowed to a smaller bitwidth.
; See PR34046, PR16726, and PR39624 for motivating examples:
; https://bugs.llvm.org/show_bug.cgi?id=34046
; https://bugs.llvm.org/show_bug.cgi?id=16726
; https://bugs.llvm.org/show_bug.cgi?id=39624
define i16 @rotate_left_16bit(i16 %v, i32 %shift) {
; CHECK-LABEL: @rotate_left_16bit(
; CHECK-NEXT: [[TMP1:%.*]] = trunc i32 [[SHIFT:%.*]] to i16
; CHECK-NEXT: [[CONV2:%.*]] = call i16 @llvm.fshl.i16(i16 [[V:%.*]], i16 [[V]], i16 [[TMP1]])
; CHECK-NEXT: ret i16 [[CONV2]]
;
%and = and i32 %shift, 15
%conv = zext i16 %v to i32
%shl = shl i32 %conv, %and
%sub = sub i32 16, %and
%shr = lshr i32 %conv, %sub
%or = or i32 %shr, %shl
%conv2 = trunc i32 %or to i16
ret i16 %conv2
}
; Commute the 'or' operands and try a vector type.
define <2 x i16> @rotate_left_commute_16bit_vec(<2 x i16> %v, <2 x i32> %shift) {
; CHECK-LABEL: @rotate_left_commute_16bit_vec(
; CHECK-NEXT: [[TMP1:%.*]] = trunc <2 x i32> [[SHIFT:%.*]] to <2 x i16>
; CHECK-NEXT: [[CONV2:%.*]] = call <2 x i16> @llvm.fshl.v2i16(<2 x i16> [[V:%.*]], <2 x i16> [[V]], <2 x i16> [[TMP1]])
; CHECK-NEXT: ret <2 x i16> [[CONV2]]
;
%and = and <2 x i32> %shift, <i32 15, i32 15>
%conv = zext <2 x i16> %v to <2 x i32>
%shl = shl <2 x i32> %conv, %and
%sub = sub <2 x i32> <i32 16, i32 16>, %and
%shr = lshr <2 x i32> %conv, %sub
%or = or <2 x i32> %shl, %shr
%conv2 = trunc <2 x i32> %or to <2 x i16>
ret <2 x i16> %conv2
}
; Change the size, rotation direction (the subtract is on the left-shift), and mask op.
define i8 @rotate_right_8bit(i8 %v, i3 %shift) {
; CHECK-LABEL: @rotate_right_8bit(
; CHECK-NEXT: [[TMP1:%.*]] = zext i3 [[SHIFT:%.*]] to i8
; CHECK-NEXT: [[CONV2:%.*]] = call i8 @llvm.fshr.i8(i8 [[V:%.*]], i8 [[V]], i8 [[TMP1]])
; CHECK-NEXT: ret i8 [[CONV2]]
;
%and = zext i3 %shift to i32
%conv = zext i8 %v to i32
%shr = lshr i32 %conv, %and
%sub = sub i32 8, %and
%shl = shl i32 %conv, %sub
%or = or i32 %shl, %shr
%conv2 = trunc i32 %or to i8
ret i8 %conv2
}
; The shifted value does not need to be a zexted value; here it is masked.
; The shift mask could be less than the bitwidth, but this is still ok.
define i8 @rotate_right_commute_8bit(i32 %v, i32 %shift) {
; CHECK-LABEL: @rotate_right_commute_8bit(
; CHECK-NEXT: [[TMP1:%.*]] = trunc i32 [[SHIFT:%.*]] to i8
; CHECK-NEXT: [[TMP2:%.*]] = and i8 [[TMP1]], 3
; CHECK-NEXT: [[TMP3:%.*]] = trunc i32 [[V:%.*]] to i8
; CHECK-NEXT: [[CONV2:%.*]] = call i8 @llvm.fshr.i8(i8 [[TMP3]], i8 [[TMP3]], i8 [[TMP2]])
; CHECK-NEXT: ret i8 [[CONV2]]
;
%and = and i32 %shift, 3
%conv = and i32 %v, 255
%shr = lshr i32 %conv, %and
%sub = sub i32 8, %and
%shl = shl i32 %conv, %sub
%or = or i32 %shr, %shl
%conv2 = trunc i32 %or to i8
ret i8 %conv2
}
; If the original source does not mask the shift amount,
; we still do the transform by adding masks to make it safe.
define i8 @rotate8_not_safe(i8 %v, i32 %shamt) {
; CHECK-LABEL: @rotate8_not_safe(
; CHECK-NEXT: [[TMP1:%.*]] = trunc i32 [[SHAMT:%.*]] to i8
; CHECK-NEXT: [[RET:%.*]] = call i8 @llvm.fshl.i8(i8 [[V:%.*]], i8 [[V]], i8 [[TMP1]])
; CHECK-NEXT: ret i8 [[RET]]
;
%conv = zext i8 %v to i32
%sub = sub i32 8, %shamt
%shr = lshr i32 %conv, %sub
%shl = shl i32 %conv, %shamt
%or = or i32 %shr, %shl
%ret = trunc i32 %or to i8
ret i8 %ret
}
; A non-power-of-2 destination type can't be masked as above.
define i9 @rotate9_not_safe(i9 %v, i32 %shamt) {
; CHECK-LABEL: @rotate9_not_safe(
; CHECK-NEXT: [[CONV:%.*]] = zext i9 [[V:%.*]] to i32
; CHECK-NEXT: [[SUB:%.*]] = sub i32 9, [[SHAMT:%.*]]
; CHECK-NEXT: [[SHR:%.*]] = lshr i32 [[CONV]], [[SUB]]
; CHECK-NEXT: [[SHL:%.*]] = shl i32 [[CONV]], [[SHAMT]]
; CHECK-NEXT: [[OR:%.*]] = or i32 [[SHR]], [[SHL]]
; CHECK-NEXT: [[RET:%.*]] = trunc i32 [[OR]] to i9
; CHECK-NEXT: ret i9 [[RET]]
;
%conv = zext i9 %v to i32
%sub = sub i32 9, %shamt
%shr = lshr i32 %conv, %sub
%shl = shl i32 %conv, %shamt
%or = or i32 %shr, %shl
%ret = trunc i32 %or to i9
ret i9 %ret
}
; We should narrow (v << (s & 15)) | (v >> (-s & 15))
; when both v and s have been promoted.
define i16 @rotateleft_16_neg_mask(i16 %v, i16 %shamt) {
; CHECK-LABEL: @rotateleft_16_neg_mask(
; CHECK-NEXT: [[RET:%.*]] = call i16 @llvm.fshl.i16(i16 [[V:%.*]], i16 [[V]], i16 [[SHAMT:%.*]])
; CHECK-NEXT: ret i16 [[RET]]
;
%neg = sub i16 0, %shamt
%lshamt = and i16 %shamt, 15
%lshamtconv = zext i16 %lshamt to i32
%rshamt = and i16 %neg, 15
%rshamtconv = zext i16 %rshamt to i32
%conv = zext i16 %v to i32
%shl = shl i32 %conv, %lshamtconv
%shr = lshr i32 %conv, %rshamtconv
%or = or i32 %shr, %shl
%ret = trunc i32 %or to i16
ret i16 %ret
}
define i16 @rotateleft_16_neg_mask_commute(i16 %v, i16 %shamt) {
; CHECK-LABEL: @rotateleft_16_neg_mask_commute(
; CHECK-NEXT: [[RET:%.*]] = call i16 @llvm.fshl.i16(i16 [[V:%.*]], i16 [[V]], i16 [[SHAMT:%.*]])
; CHECK-NEXT: ret i16 [[RET]]
;
%neg = sub i16 0, %shamt
%lshamt = and i16 %shamt, 15
%lshamtconv = zext i16 %lshamt to i32
%rshamt = and i16 %neg, 15
%rshamtconv = zext i16 %rshamt to i32
%conv = zext i16 %v to i32
%shl = shl i32 %conv, %lshamtconv
%shr = lshr i32 %conv, %rshamtconv
%or = or i32 %shl, %shr
%ret = trunc i32 %or to i16
ret i16 %ret
}
define i8 @rotateright_8_neg_mask(i8 %v, i8 %shamt) {
; CHECK-LABEL: @rotateright_8_neg_mask(
; CHECK-NEXT: [[RET:%.*]] = call i8 @llvm.fshr.i8(i8 [[V:%.*]], i8 [[V]], i8 [[SHAMT:%.*]])
; CHECK-NEXT: ret i8 [[RET]]
;
%neg = sub i8 0, %shamt
%rshamt = and i8 %shamt, 7
%rshamtconv = zext i8 %rshamt to i32
%lshamt = and i8 %neg, 7
%lshamtconv = zext i8 %lshamt to i32
%conv = zext i8 %v to i32
%shl = shl i32 %conv, %lshamtconv
%shr = lshr i32 %conv, %rshamtconv
%or = or i32 %shr, %shl
%ret = trunc i32 %or to i8
ret i8 %ret
}
define i8 @rotateright_8_neg_mask_commute(i8 %v, i8 %shamt) {
; CHECK-LABEL: @rotateright_8_neg_mask_commute(
; CHECK-NEXT: [[RET:%.*]] = call i8 @llvm.fshr.i8(i8 [[V:%.*]], i8 [[V]], i8 [[SHAMT:%.*]])
; CHECK-NEXT: ret i8 [[RET]]
;
%neg = sub i8 0, %shamt
%rshamt = and i8 %shamt, 7
%rshamtconv = zext i8 %rshamt to i32
%lshamt = and i8 %neg, 7
%lshamtconv = zext i8 %lshamt to i32
%conv = zext i8 %v to i32
%shl = shl i32 %conv, %lshamtconv
%shr = lshr i32 %conv, %rshamtconv
%or = or i32 %shl, %shr
%ret = trunc i32 %or to i8
ret i8 %ret
}
; The shift amount may already be in the wide type,
; so we need to truncate it going into the rotate pattern.
define i16 @rotateright_16_neg_mask_wide_amount(i16 %v, i32 %shamt) {
; CHECK-LABEL: @rotateright_16_neg_mask_wide_amount(
; CHECK-NEXT: [[TMP1:%.*]] = trunc i32 [[SHAMT:%.*]] to i16
; CHECK-NEXT: [[RET:%.*]] = call i16 @llvm.fshr.i16(i16 [[V:%.*]], i16 [[V]], i16 [[TMP1]])
; CHECK-NEXT: ret i16 [[RET]]
;
%neg = sub i32 0, %shamt
%rshamt = and i32 %shamt, 15
%lshamt = and i32 %neg, 15
%conv = zext i16 %v to i32
%shl = shl i32 %conv, %lshamt
%shr = lshr i32 %conv, %rshamt
%or = or i32 %shr, %shl
%ret = trunc i32 %or to i16
ret i16 %ret
}
define i16 @rotateright_16_neg_mask_wide_amount_commute(i16 %v, i32 %shamt) {
; CHECK-LABEL: @rotateright_16_neg_mask_wide_amount_commute(
; CHECK-NEXT: [[TMP1:%.*]] = trunc i32 [[SHAMT:%.*]] to i16
; CHECK-NEXT: [[RET:%.*]] = call i16 @llvm.fshr.i16(i16 [[V:%.*]], i16 [[V]], i16 [[TMP1]])
; CHECK-NEXT: ret i16 [[RET]]
;
%neg = sub i32 0, %shamt
%rshamt = and i32 %shamt, 15
%lshamt = and i32 %neg, 15
%conv = zext i16 %v to i32
%shl = shl i32 %conv, %lshamt
%shr = lshr i32 %conv, %rshamt
%or = or i32 %shl, %shr
%ret = trunc i32 %or to i16
ret i16 %ret
}
define i8 @rotateleft_8_neg_mask_wide_amount(i8 %v, i32 %shamt) {
; CHECK-LABEL: @rotateleft_8_neg_mask_wide_amount(
; CHECK-NEXT: [[TMP1:%.*]] = trunc i32 [[SHAMT:%.*]] to i8
; CHECK-NEXT: [[RET:%.*]] = call i8 @llvm.fshl.i8(i8 [[V:%.*]], i8 [[V]], i8 [[TMP1]])
; CHECK-NEXT: ret i8 [[RET]]
;
%neg = sub i32 0, %shamt
%lshamt = and i32 %shamt, 7
%rshamt = and i32 %neg, 7
%conv = zext i8 %v to i32
%shl = shl i32 %conv, %lshamt
%shr = lshr i32 %conv, %rshamt
%or = or i32 %shr, %shl
%ret = trunc i32 %or to i8
ret i8 %ret
}
define i8 @rotateleft_8_neg_mask_wide_amount_commute(i8 %v, i32 %shamt) {
; CHECK-LABEL: @rotateleft_8_neg_mask_wide_amount_commute(
; CHECK-NEXT: [[TMP1:%.*]] = trunc i32 [[SHAMT:%.*]] to i8
; CHECK-NEXT: [[RET:%.*]] = call i8 @llvm.fshl.i8(i8 [[V:%.*]], i8 [[V]], i8 [[TMP1]])
; CHECK-NEXT: ret i8 [[RET]]
;
%neg = sub i32 0, %shamt
%lshamt = and i32 %shamt, 7
%rshamt = and i32 %neg, 7
%conv = zext i8 %v to i32
%shl = shl i32 %conv, %lshamt
%shr = lshr i32 %conv, %rshamt
%or = or i32 %shl, %shr
%ret = trunc i32 %or to i8
ret i8 %ret
}
; Non-power-of-2 types. This could be transformed, but it's not a typical rotate pattern.
define i9 @rotateleft_9_neg_mask_wide_amount_commute(i9 %v, i33 %shamt) {
; CHECK-LABEL: @rotateleft_9_neg_mask_wide_amount_commute(
; CHECK-NEXT: [[NEG:%.*]] = sub i33 0, [[SHAMT:%.*]]
; CHECK-NEXT: [[LSHAMT:%.*]] = and i33 [[SHAMT]], 8
; CHECK-NEXT: [[RSHAMT:%.*]] = and i33 [[NEG]], 8
; CHECK-NEXT: [[CONV:%.*]] = zext i9 [[V:%.*]] to i33
; CHECK-NEXT: [[SHL:%.*]] = shl i33 [[CONV]], [[LSHAMT]]
; CHECK-NEXT: [[SHR:%.*]] = lshr i33 [[CONV]], [[RSHAMT]]
; CHECK-NEXT: [[OR:%.*]] = or i33 [[SHL]], [[SHR]]
; CHECK-NEXT: [[RET:%.*]] = trunc i33 [[OR]] to i9
; CHECK-NEXT: ret i9 [[RET]]
;
%neg = sub i33 0, %shamt
%lshamt = and i33 %shamt, 8
%rshamt = and i33 %neg, 8
%conv = zext i9 %v to i33
%shl = shl i33 %conv, %lshamt
%shr = lshr i33 %conv, %rshamt
%or = or i33 %shl, %shr
%ret = trunc i33 %or to i9
ret i9 %ret
}
; Convert select pattern to masked shift that ends in 'or'.
define i32 @rotr_select(i32 %x, i32 %shamt) {
; CHECK-LABEL: @rotr_select(
; CHECK-NEXT: [[R:%.*]] = call i32 @llvm.fshr.i32(i32 [[X:%.*]], i32 [[X]], i32 [[SHAMT:%.*]])
; CHECK-NEXT: ret i32 [[R]]
;
%cmp = icmp eq i32 %shamt, 0
%sub = sub i32 32, %shamt
%shr = lshr i32 %x, %shamt
%shl = shl i32 %x, %sub
%or = or i32 %shr, %shl
%r = select i1 %cmp, i32 %x, i32 %or
ret i32 %r
}
; Convert select pattern to masked shift that ends in 'or'.
define i8 @rotr_select_commute(i8 %x, i8 %shamt) {
; CHECK-LABEL: @rotr_select_commute(
; CHECK-NEXT: [[R:%.*]] = call i8 @llvm.fshr.i8(i8 [[X:%.*]], i8 [[X]], i8 [[SHAMT:%.*]])
; CHECK-NEXT: ret i8 [[R]]
;
%cmp = icmp eq i8 %shamt, 0
%sub = sub i8 8, %shamt
%shr = lshr i8 %x, %shamt
%shl = shl i8 %x, %sub
%or = or i8 %shl, %shr
%r = select i1 %cmp, i8 %x, i8 %or
ret i8 %r
}
; Convert select pattern to masked shift that ends in 'or'.
define i16 @rotl_select(i16 %x, i16 %shamt) {
; CHECK-LABEL: @rotl_select(
; CHECK-NEXT: [[R:%.*]] = call i16 @llvm.fshl.i16(i16 [[X:%.*]], i16 [[X]], i16 [[SHAMT:%.*]])
; CHECK-NEXT: ret i16 [[R]]
;
%cmp = icmp eq i16 %shamt, 0
%sub = sub i16 16, %shamt
%shr = lshr i16 %x, %sub
%shl = shl i16 %x, %shamt
%or = or i16 %shr, %shl
%r = select i1 %cmp, i16 %x, i16 %or
ret i16 %r
}
; Convert select pattern to masked shift that ends in 'or'.
define <2 x i64> @rotl_select_commute(<2 x i64> %x, <2 x i64> %shamt) {
; CHECK-LABEL: @rotl_select_commute(
; CHECK-NEXT: [[R:%.*]] = call <2 x i64> @llvm.fshl.v2i64(<2 x i64> [[X:%.*]], <2 x i64> [[X]], <2 x i64> [[SHAMT:%.*]])
; CHECK-NEXT: ret <2 x i64> [[R]]
;
%cmp = icmp eq <2 x i64> %shamt, zeroinitializer
%sub = sub <2 x i64> <i64 64, i64 64>, %shamt
%shr = lshr <2 x i64> %x, %sub
%shl = shl <2 x i64> %x, %shamt
%or = or <2 x i64> %shl, %shr
%r = select <2 x i1> %cmp, <2 x i64> %x, <2 x i64> %or
ret <2 x i64> %r
}
; Negative test - the transform is only valid with power-of-2 types.
define i24 @rotl_select_weird_type(i24 %x, i24 %shamt) {
; CHECK-LABEL: @rotl_select_weird_type(
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i24 [[SHAMT:%.*]], 0
; CHECK-NEXT: [[SUB:%.*]] = sub i24 24, [[SHAMT]]
; CHECK-NEXT: [[SHR:%.*]] = lshr i24 [[X:%.*]], [[SUB]]
; CHECK-NEXT: [[SHL:%.*]] = shl i24 [[X]], [[SHAMT]]
; CHECK-NEXT: [[OR:%.*]] = or i24 [[SHL]], [[SHR]]
; CHECK-NEXT: [[R:%.*]] = select i1 [[CMP]], i24 [[X]], i24 [[OR]]
; CHECK-NEXT: ret i24 [[R]]
;
%cmp = icmp eq i24 %shamt, 0
%sub = sub i24 24, %shamt
%shr = lshr i24 %x, %sub
%shl = shl i24 %x, %shamt
%or = or i24 %shl, %shr
%r = select i1 %cmp, i24 %x, i24 %or
ret i24 %r
}
; Test that the transform doesn't crash when there's an "or" with a ConstantExpr operand.
@external_global = external global i8
define i32 @rotl_constant_expr(i32 %shamt) {
; CHECK-LABEL: @rotl_constant_expr(
; CHECK-NEXT: [[SHR:%.*]] = lshr i32 ptrtoint (i8* @external_global to i32), [[SHAMT:%.*]]
; CHECK-NEXT: [[R:%.*]] = or i32 [[SHR]], shl (i32 ptrtoint (i8* @external_global to i32), i32 11)
; CHECK-NEXT: ret i32 [[R]]
;
%shr = lshr i32 ptrtoint (i8* @external_global to i32), %shamt
%r = or i32 %shr, shl (i32 ptrtoint (i8* @external_global to i32), i32 11)
ret i32 %r
}
; PR20750 - https://bugs.llvm.org/show_bug.cgi?id=20750
; This IR corresponds to C source where the shift amount is a smaller type than the rotated value:
; unsigned int rotate32_doubleand1(unsigned int v, unsigned char r) { r = r & 31; return (v << r) | (v >> (((32 - r)) & 31)); }
define i32 @rotateleft32_doubleand1(i32 %v, i8 %r) {
; CHECK-LABEL: @rotateleft32_doubleand1(
; CHECK-NEXT: [[Z:%.*]] = zext i8 [[R:%.*]] to i32
; CHECK-NEXT: [[OR:%.*]] = call i32 @llvm.fshl.i32(i32 [[V:%.*]], i32 [[V]], i32 [[Z]])
; CHECK-NEXT: ret i32 [[OR]]
;
%m = and i8 %r, 31
%z = zext i8 %m to i32
%neg = sub nsw i32 0, %z
%and2 = and i32 %neg, 31
%shl = shl i32 %v, %z
%shr = lshr i32 %v, %and2
%or = or i32 %shr, %shl
ret i32 %or
}
define i32 @rotateright32_doubleand1(i32 %v, i16 %r) {
; CHECK-LABEL: @rotateright32_doubleand1(
; CHECK-NEXT: [[Z:%.*]] = zext i16 [[R:%.*]] to i32
; CHECK-NEXT: [[OR:%.*]] = call i32 @llvm.fshr.i32(i32 [[V:%.*]], i32 [[V]], i32 [[Z]])
; CHECK-NEXT: ret i32 [[OR]]
;
%m = and i16 %r, 31
%z = zext i16 %m to i32
%neg = sub nsw i32 0, %z
%and2 = and i32 %neg, 31
%shl = shl i32 %v, %and2
%shr = lshr i32 %v, %z
%or = or i32 %shr, %shl
ret i32 %or
}