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1; This test makes sure that these instructions are properly eliminated.
2;
3; RUN: opt < %s -instcombine -S | FileCheck %s
4
5define i32 @test1(i32 %A) {
6; CHECK-LABEL: @test1(
7; CHECK: ret i32 %A
8        %B = shl i32 %A, 0              ; <i32> [#uses=1]
9        ret i32 %B
10}
11
12define i32 @test2(i8 %A) {
13; CHECK-LABEL: @test2(
14; CHECK: ret i32 0
15        %shift.upgrd.1 = zext i8 %A to i32              ; <i32> [#uses=1]
16        %B = shl i32 0, %shift.upgrd.1          ; <i32> [#uses=1]
17        ret i32 %B
18}
19
20define i32 @test3(i32 %A) {
21; CHECK-LABEL: @test3(
22; CHECK: ret i32 %A
23        %B = ashr i32 %A, 0             ; <i32> [#uses=1]
24        ret i32 %B
25}
26
27define i32 @test4(i8 %A) {
28; CHECK-LABEL: @test4(
29; CHECK: ret i32 0
30        %shift.upgrd.2 = zext i8 %A to i32              ; <i32> [#uses=1]
31        %B = ashr i32 0, %shift.upgrd.2         ; <i32> [#uses=1]
32        ret i32 %B
33}
34
35
36define i32 @test5(i32 %A) {
37; CHECK-LABEL: @test5(
38; CHECK: ret i32 undef
39        %B = lshr i32 %A, 32  ;; shift all bits out
40        ret i32 %B
41}
42
43define <4 x i32> @test5_splat_vector(<4 x i32> %A) {
44; CHECK-LABEL: @test5_splat_vector(
45; CHECK: ret <4 x i32> undef
46  %B = lshr <4 x i32> %A, <i32 32, i32 32, i32 32, i32 32>     ;; shift all bits out
47  ret <4 x i32> %B
48}
49
50define <4 x i32> @test5_zero_vector(<4 x i32> %A) {
51; CHECK-LABEL: @test5_zero_vector(
52; CHECK-NEXT: ret <4 x i32> %A
53  %B = lshr <4 x i32> %A, zeroinitializer
54  ret <4 x i32> %B
55}
56
57define <4 x i32> @test5_non_splat_vector(<4 x i32> %A) {
58; CHECK-LABEL: @test5_non_splat_vector(
59; CHECK-NOT: ret <4 x i32> undef
60  %B = shl <4 x i32> %A, <i32 32, i32 1, i32 2, i32 3>
61  ret <4 x i32> %B
62}
63
64define i32 @test5a(i32 %A) {
65; CHECK-LABEL: @test5a(
66; CHECK: ret i32 undef
67        %B = shl i32 %A, 32     ;; shift all bits out
68        ret i32 %B
69}
70
71define <4 x i32> @test5a_splat_vector(<4 x i32> %A) {
72; CHECK-LABEL: @test5a_splat_vector(
73; CHECK: ret <4 x i32> undef
74  %B = shl <4 x i32> %A, <i32 32, i32 32, i32 32, i32 32>     ;; shift all bits out
75  ret <4 x i32> %B
76}
77
78define <4 x i32> @test5a_non_splat_vector(<4 x i32> %A) {
79; CHECK-LABEL: @test5a_non_splat_vector(
80; CHECK-NOT: ret <4 x i32> undef
81  %B = shl <4 x i32> %A, <i32 32, i32 1, i32 2, i32 3>
82  ret <4 x i32> %B
83}
84
85define i32 @test5b() {
86; CHECK-LABEL: @test5b(
87; CHECK: ret i32 -1
88        %B = ashr i32 undef, 2  ;; top two bits must be equal, so not undef
89        ret i32 %B
90}
91
92define i32 @test5b2(i32 %A) {
93; CHECK-LABEL: @test5b2(
94; CHECK: ret i32 -1
95        %B = ashr i32 undef, %A  ;; top %A bits must be equal, so not undef
96        ret i32 %B
97}
98
99define i32 @test6(i32 %A) {
100; CHECK-LABEL: @test6(
101; CHECK-NEXT: mul i32 %A, 6
102; CHECK-NEXT: ret i32
103        %B = shl i32 %A, 1      ;; convert to an mul instruction
104        %C = mul i32 %B, 3
105        ret i32 %C
106}
107
108define i32 @test6a(i32 %A) {
109; CHECK-LABEL: @test6a(
110; CHECK-NEXT: mul i32 %A, 6
111; CHECK-NEXT: ret i32
112        %B = mul i32 %A, 3
113        %C = shl i32 %B, 1      ;; convert to an mul instruction
114        ret i32 %C
115}
116
117define i32 @test7(i8 %A) {
118; CHECK-LABEL: @test7(
119; CHECK-NEXT: ret i32 -1
120        %shift.upgrd.3 = zext i8 %A to i32
121        %B = ashr i32 -1, %shift.upgrd.3  ;; Always equal to -1
122        ret i32 %B
123}
124
125;; (A << 5) << 3 === A << 8 == 0
126define i8 @test8(i8 %A) {
127; CHECK-LABEL: @test8(
128; CHECK: ret i8 0
129        %B = shl i8 %A, 5               ; <i8> [#uses=1]
130        %C = shl i8 %B, 3               ; <i8> [#uses=1]
131        ret i8 %C
132}
133
134;; (A << 7) >> 7 === A & 1
135define i8 @test9(i8 %A) {
136; CHECK-LABEL: @test9(
137; CHECK-NEXT: and i8 %A, 1
138; CHECK-NEXT: ret i8
139        %B = shl i8 %A, 7               ; <i8> [#uses=1]
140        %C = lshr i8 %B, 7              ; <i8> [#uses=1]
141        ret i8 %C
142}
143
144;; This transformation is deferred to DAGCombine:
145;; (A >> 7) << 7 === A & 128
146;; The shl may be valuable to scalar evolution.
147define i8 @test10(i8 %A) {
148; CHECK-LABEL: @test10(
149; CHECK-NEXT: and i8 %A, -128
150; CHECK-NEXT: ret i8
151        %B = lshr i8 %A, 7              ; <i8> [#uses=1]
152        %C = shl i8 %B, 7               ; <i8> [#uses=1]
153        ret i8 %C
154}
155
156;; Allow the simplification when the lshr shift is exact.
157define i8 @test10a(i8 %A) {
158; CHECK-LABEL: @test10a(
159; CHECK-NEXT: ret i8 %A
160        %B = lshr exact i8 %A, 7
161        %C = shl i8 %B, 7
162        ret i8 %C
163}
164
165;; This transformation is deferred to DAGCombine:
166;; (A >> 3) << 4 === (A & 0x1F) << 1
167;; The shl may be valuable to scalar evolution.
168define i8 @test11(i8 %A) {
169; CHECK-LABEL: @test11(
170; CHECK: shl i8
171; CHECK-NEXT: ret i8
172        %a = mul i8 %A, 3               ; <i8> [#uses=1]
173        %B = lshr i8 %a, 3              ; <i8> [#uses=1]
174        %C = shl i8 %B, 4               ; <i8> [#uses=1]
175        ret i8 %C
176}
177
178;; Allow the simplification in InstCombine when the lshr shift is exact.
179define i8 @test11a(i8 %A) {
180; CHECK-LABEL: @test11a(
181; CHECK-NEXT: mul i8 %A, 6
182; CHECK-NEXT: ret i8
183        %a = mul i8 %A, 3
184        %B = lshr exact i8 %a, 3
185        %C = shl i8 %B, 4
186        ret i8 %C
187}
188
189;; This is deferred to DAGCombine unless %B is single-use.
190;; (A >> 8) << 8 === A & -256
191define i32 @test12(i32 %A) {
192; CHECK-LABEL: @test12(
193; CHECK-NEXT: and i32 %A, -256
194; CHECK-NEXT: ret i32
195        %B = ashr i32 %A, 8             ; <i32> [#uses=1]
196        %C = shl i32 %B, 8              ; <i32> [#uses=1]
197        ret i32 %C
198}
199
200;; This transformation is deferred to DAGCombine:
201;; (A >> 3) << 4 === (A & -8) * 2
202;; The shl may be valuable to scalar evolution.
203define i8 @test13(i8 %A) {
204; CHECK-LABEL: @test13(
205; CHECK: shl i8
206; CHECK-NEXT: ret i8
207        %a = mul i8 %A, 3               ; <i8> [#uses=1]
208        %B = ashr i8 %a, 3              ; <i8> [#uses=1]
209        %C = shl i8 %B, 4               ; <i8> [#uses=1]
210        ret i8 %C
211}
212
213define i8 @test13a(i8 %A) {
214; CHECK-LABEL: @test13a(
215; CHECK-NEXT: mul i8 %A, 6
216; CHECK-NEXT: ret i8
217        %a = mul i8 %A, 3
218        %B = ashr exact i8 %a, 3
219        %C = shl i8 %B, 4
220        ret i8 %C
221}
222
223;; D = ((B | 1234) << 4) === ((B << 4)|(1234 << 4)
224define i32 @test14(i32 %A) {
225; CHECK-LABEL: @test14(
226; CHECK-NEXT: %B = and i32 %A, -19760
227; CHECK-NEXT: or i32 %B, 19744
228; CHECK-NEXT: ret i32
229        %B = lshr i32 %A, 4             ; <i32> [#uses=1]
230        %C = or i32 %B, 1234            ; <i32> [#uses=1]
231        %D = shl i32 %C, 4              ; <i32> [#uses=1]
232        ret i32 %D
233}
234
235;; D = ((B | 1234) << 4) === ((B << 4)|(1234 << 4)
236define i32 @test14a(i32 %A) {
237; CHECK-LABEL: @test14a(
238; CHECK-NEXT: and i32 %A, 77
239; CHECK-NEXT: ret i32
240        %B = shl i32 %A, 4              ; <i32> [#uses=1]
241        %C = and i32 %B, 1234           ; <i32> [#uses=1]
242        %D = lshr i32 %C, 4             ; <i32> [#uses=1]
243        ret i32 %D
244}
245
246define i32 @test15(i1 %C) {
247; CHECK-LABEL: @test15(
248; CHECK-NEXT: select i1 %C, i32 12, i32 4
249; CHECK-NEXT: ret i32
250        %A = select i1 %C, i32 3, i32 1         ; <i32> [#uses=1]
251        %V = shl i32 %A, 2              ; <i32> [#uses=1]
252        ret i32 %V
253}
254
255define i32 @test15a(i1 %C) {
256; CHECK-LABEL: @test15a(
257; CHECK-NEXT: select i1 %C, i32 512, i32 128
258; CHECK-NEXT: ret i32
259        %A = select i1 %C, i8 3, i8 1           ; <i8> [#uses=1]
260        %shift.upgrd.4 = zext i8 %A to i32              ; <i32> [#uses=1]
261        %V = shl i32 64, %shift.upgrd.4         ; <i32> [#uses=1]
262        ret i32 %V
263}
264
265define i1 @test16(i32 %X) {
266; CHECK-LABEL: @test16(
267; CHECK-NEXT: and i32 %X, 16
268; CHECK-NEXT: icmp ne i32
269; CHECK-NEXT: ret i1
270        %tmp.3 = ashr i32 %X, 4
271        %tmp.6 = and i32 %tmp.3, 1
272        %tmp.7 = icmp ne i32 %tmp.6, 0
273        ret i1 %tmp.7
274}
275
276define i1 @test17(i32 %A) {
277; CHECK-LABEL: @test17(
278; CHECK-NEXT: and i32 %A, -8
279; CHECK-NEXT: icmp eq i32
280; CHECK-NEXT: ret i1
281        %B = lshr i32 %A, 3             ; <i32> [#uses=1]
282        %C = icmp eq i32 %B, 1234               ; <i1> [#uses=1]
283        ret i1 %C
284}
285
286
287define i1 @test18(i8 %A) {
288; CHECK-LABEL: @test18(
289; CHECK: ret i1 false
290
291        %B = lshr i8 %A, 7              ; <i8> [#uses=1]
292        ;; false
293        %C = icmp eq i8 %B, 123         ; <i1> [#uses=1]
294        ret i1 %C
295}
296
297define i1 @test19(i32 %A) {
298; CHECK-LABEL: @test19(
299; CHECK-NEXT: icmp ult i32 %A, 4
300; CHECK-NEXT: ret i1
301        %B = ashr i32 %A, 2             ; <i32> [#uses=1]
302        ;; (X & -4) == 0
303        %C = icmp eq i32 %B, 0          ; <i1> [#uses=1]
304        ret i1 %C
305}
306
307
308define i1 @test19a(i32 %A) {
309; CHECK-LABEL: @test19a(
310; CHECK-NEXT: icmp ugt i32 %A, -5
311; CHECK-NEXT: ret i1
312        %B = ashr i32 %A, 2             ; <i32> [#uses=1]
313        ;; X >u ~4
314        %C = icmp eq i32 %B, -1         ; <i1> [#uses=1]
315        ret i1 %C
316}
317
318define i1 @test20(i8 %A) {
319; CHECK-LABEL: @test20(
320; CHECK: ret i1 false
321        %B = ashr i8 %A, 7              ; <i8> [#uses=1]
322        ;; false
323        %C = icmp eq i8 %B, 123         ; <i1> [#uses=1]
324        ret i1 %C
325}
326
327define i1 @test21(i8 %A) {
328; CHECK-LABEL: @test21(
329; CHECK-NEXT: and i8 %A, 15
330; CHECK-NEXT: icmp eq i8
331; CHECK-NEXT: ret i1
332        %B = shl i8 %A, 4               ; <i8> [#uses=1]
333        %C = icmp eq i8 %B, -128                ; <i1> [#uses=1]
334        ret i1 %C
335}
336
337define i1 @test22(i8 %A) {
338; CHECK-LABEL: @test22(
339; CHECK-NEXT: and i8 %A, 15
340; CHECK-NEXT: icmp eq i8
341; CHECK-NEXT: ret i1
342        %B = shl i8 %A, 4               ; <i8> [#uses=1]
343        %C = icmp eq i8 %B, 0           ; <i1> [#uses=1]
344        ret i1 %C
345}
346
347define i8 @test23(i32 %A) {
348; CHECK-LABEL: @test23(
349; CHECK-NEXT: trunc i32 %A to i8
350; CHECK-NEXT: ret i8
351
352        ;; casts not needed
353        %B = shl i32 %A, 24             ; <i32> [#uses=1]
354        %C = ashr i32 %B, 24            ; <i32> [#uses=1]
355        %D = trunc i32 %C to i8         ; <i8> [#uses=1]
356        ret i8 %D
357}
358
359define i8 @test24(i8 %X) {
360; CHECK-LABEL: @test24(
361; CHECK-NEXT: and i8 %X, 3
362; CHECK-NEXT: ret i8
363        %Y = and i8 %X, -5              ; <i8> [#uses=1]
364        %Z = shl i8 %Y, 5               ; <i8> [#uses=1]
365        %Q = ashr i8 %Z, 5              ; <i8> [#uses=1]
366        ret i8 %Q
367}
368
369define i32 @test25(i32 %tmp.2, i32 %AA) {
370; CHECK-LABEL: @test25(
371; CHECK-NEXT: and i32 %tmp.2, -131072
372; CHECK-NEXT: add i32 %{{[^,]*}}, %AA
373; CHECK-NEXT: and i32 %{{[^,]*}}, -131072
374; CHECK-NEXT: ret i32
375        %x = lshr i32 %AA, 17           ; <i32> [#uses=1]
376        %tmp.3 = lshr i32 %tmp.2, 17            ; <i32> [#uses=1]
377        %tmp.5 = add i32 %tmp.3, %x             ; <i32> [#uses=1]
378        %tmp.6 = shl i32 %tmp.5, 17             ; <i32> [#uses=1]
379        ret i32 %tmp.6
380}
381
382define <2 x i32> @test25_vector(<2 x i32> %tmp.2, <2 x i32> %AA) {
383; CHECK-LABEL: @test25_vector(
384; CHECK: %tmp.3 = lshr <2 x i32> %tmp.2, <i32 17, i32 17>
385; CHECK-NEXT: shl <2 x i32> %tmp.3, <i32 17, i32 17>
386; CHECK-NEXT: add <2 x i32> %tmp.51, %AA
387; CHECK-NEXT: and <2 x i32> %x2, <i32 -131072, i32 -131072>
388; CHECK-NEXT: ret <2 x i32>
389  %x = lshr <2 x i32> %AA, <i32 17, i32 17>
390  %tmp.3 = lshr <2 x i32> %tmp.2, <i32 17, i32 17>
391  %tmp.5 = add <2 x i32> %tmp.3, %x
392  %tmp.6 = shl <2 x i32> %tmp.5, <i32 17, i32 17>
393  ret <2 x i32> %tmp.6
394}
395
396;; handle casts between shifts.
397define i32 @test26(i32 %A) {
398; CHECK-LABEL: @test26(
399; CHECK-NEXT: and i32 %A, -2
400; CHECK-NEXT: ret i32
401        %B = lshr i32 %A, 1             ; <i32> [#uses=1]
402        %C = bitcast i32 %B to i32              ; <i32> [#uses=1]
403        %D = shl i32 %C, 1              ; <i32> [#uses=1]
404        ret i32 %D
405}
406
407
408define i1 @test27(i32 %x) nounwind {
409; CHECK-LABEL: @test27(
410; CHECK-NEXT: and i32 %x, 8
411; CHECK-NEXT: icmp ne i32
412; CHECK-NEXT: ret i1
413  %y = lshr i32 %x, 3
414  %z = trunc i32 %y to i1
415  ret i1 %z
416}
417
418define i8 @test28(i8 %x) {
419entry:
420; CHECK-LABEL: @test28(
421; CHECK:     icmp slt i8 %x, 0
422; CHECK-NEXT:     br i1
423	%tmp1 = lshr i8 %x, 7
424	%cond1 = icmp ne i8 %tmp1, 0
425	br i1 %cond1, label %bb1, label %bb2
426
427bb1:
428	ret i8 0
429
430bb2:
431	ret i8 1
432}
433
434define i8 @test28a(i8 %x, i8 %y) {
435entry:
436; This shouldn't be transformed.
437; CHECK-LABEL: @test28a(
438; CHECK:     %tmp1 = lshr i8 %x, 7
439; CHECK:     %cond1 = icmp eq i8 %tmp1, 0
440; CHECK:     br i1 %cond1, label %bb2, label %bb1
441	%tmp1 = lshr i8 %x, 7
442	%cond1 = icmp ne i8 %tmp1, 0
443	br i1 %cond1, label %bb1, label %bb2
444bb1:
445	ret i8 %tmp1
446bb2:
447        %tmp2 = add i8 %tmp1, %y
448	ret i8 %tmp2
449}
450
451
452define i32 @test29(i64 %d18) {
453entry:
454	%tmp916 = lshr i64 %d18, 32
455	%tmp917 = trunc i64 %tmp916 to i32
456	%tmp10 = lshr i32 %tmp917, 31
457	ret i32 %tmp10
458; CHECK-LABEL: @test29(
459; CHECK:  %tmp916 = lshr i64 %d18, 63
460; CHECK:  %tmp10 = trunc i64 %tmp916 to i32
461}
462
463
464define i32 @test30(i32 %A, i32 %B, i32 %C) {
465	%X = shl i32 %A, %C
466	%Y = shl i32 %B, %C
467	%Z = and i32 %X, %Y
468	ret i32 %Z
469; CHECK-LABEL: @test30(
470; CHECK: %X1 = and i32 %A, %B
471; CHECK: %Z = shl i32 %X1, %C
472}
473
474define i32 @test31(i32 %A, i32 %B, i32 %C) {
475	%X = lshr i32 %A, %C
476	%Y = lshr i32 %B, %C
477	%Z = or i32 %X, %Y
478	ret i32 %Z
479; CHECK-LABEL: @test31(
480; CHECK: %X1 = or i32 %A, %B
481; CHECK: %Z = lshr i32 %X1, %C
482}
483
484define i32 @test32(i32 %A, i32 %B, i32 %C) {
485	%X = ashr i32 %A, %C
486	%Y = ashr i32 %B, %C
487	%Z = xor i32 %X, %Y
488	ret i32 %Z
489; CHECK-LABEL: @test32(
490; CHECK: %X1 = xor i32 %A, %B
491; CHECK: %Z = ashr i32 %X1, %C
492; CHECK: ret i32 %Z
493}
494
495define i1 @test33(i32 %X) {
496        %tmp1 = shl i32 %X, 7
497        %tmp2 = icmp slt i32 %tmp1, 0
498        ret i1 %tmp2
499; CHECK-LABEL: @test33(
500; CHECK: %tmp1.mask = and i32 %X, 16777216
501; CHECK: %tmp2 = icmp ne i32 %tmp1.mask, 0
502}
503
504define i1 @test34(i32 %X) {
505        %tmp1 = lshr i32 %X, 7
506        %tmp2 = icmp slt i32 %tmp1, 0
507        ret i1 %tmp2
508; CHECK-LABEL: @test34(
509; CHECK: ret i1 false
510}
511
512define i1 @test35(i32 %X) {
513        %tmp1 = ashr i32 %X, 7
514        %tmp2 = icmp slt i32 %tmp1, 0
515        ret i1 %tmp2
516; CHECK-LABEL: @test35(
517; CHECK: %tmp2 = icmp slt i32 %X, 0
518; CHECK: ret i1 %tmp2
519}
520
521define i128 @test36(i128 %A, i128 %B) {
522entry:
523  %tmp27 = shl i128 %A, 64
524  %tmp23 = shl i128 %B, 64
525  %ins = or i128 %tmp23, %tmp27
526  %tmp45 = lshr i128 %ins, 64
527  ret i128 %tmp45
528
529; CHECK-LABEL: @test36(
530; CHECK:  %tmp231 = or i128 %B, %A
531; CHECK:  %ins = and i128 %tmp231, 18446744073709551615
532; CHECK:  ret i128 %ins
533}
534
535define i64 @test37(i128 %A, i32 %B) {
536entry:
537  %tmp27 = shl i128 %A, 64
538  %tmp22 = zext i32 %B to i128
539  %tmp23 = shl i128 %tmp22, 96
540  %ins = or i128 %tmp23, %tmp27
541  %tmp45 = lshr i128 %ins, 64
542  %tmp46 = trunc i128 %tmp45 to i64
543  ret i64 %tmp46
544
545; CHECK-LABEL: @test37(
546; CHECK:  %tmp23 = shl nuw nsw i128 %tmp22, 32
547; CHECK:  %ins = or i128 %tmp23, %A
548; CHECK:  %tmp46 = trunc i128 %ins to i64
549}
550
551define i32 @test38(i32 %x) nounwind readnone {
552  %rem = srem i32 %x, 32
553  %shl = shl i32 1, %rem
554  ret i32 %shl
555; CHECK-LABEL: @test38(
556; CHECK-NEXT: and i32 %x, 31
557; CHECK-NEXT: shl i32 1
558; CHECK-NEXT: ret i32
559}
560
561; <rdar://problem/8756731>
562; CHECK-LABEL: @test39(
563define i8 @test39(i32 %a0) {
564entry:
565  %tmp4 = trunc i32 %a0 to i8
566; CHECK: and i8 %tmp49, 64
567  %tmp5 = shl i8 %tmp4, 5
568  %tmp48 = and i8 %tmp5, 32
569  %tmp49 = lshr i8 %tmp48, 5
570  %tmp50 = mul i8 %tmp49, 64
571  %tmp51 = xor i8 %tmp50, %tmp5
572  %tmp52 = and i8 %tmp51, -128
573  %tmp53 = lshr i8 %tmp52, 7
574  %tmp54 = mul i8 %tmp53, 16
575; CHECK: %0 = shl i8 %tmp4, 2
576; CHECK: %tmp54 = and i8 %0, 16
577  %tmp55 = xor i8 %tmp54, %tmp51
578; CHECK: ret i8 %tmp551
579  ret i8 %tmp55
580}
581
582; PR9809
583define i32 @test40(i32 %a, i32 %b) nounwind {
584  %shl1 = shl i32 1, %b
585  %shl2 = shl i32 %shl1, 2
586  %div = udiv i32 %a, %shl2
587  ret i32 %div
588; CHECK-LABEL: @test40(
589; CHECK-NEXT: add i32 %b, 2
590; CHECK-NEXT: lshr i32 %a
591; CHECK-NEXT: ret i32
592}
593
594define i32 @test41(i32 %a, i32 %b) nounwind {
595  %1 = shl i32 1, %b
596  %2 = shl i32 %1, 3
597  ret i32 %2
598; CHECK-LABEL: @test41(
599; CHECK-NEXT: shl i32 8, %b
600; CHECK-NEXT: ret i32
601}
602
603define i32 @test42(i32 %a, i32 %b) nounwind {
604  %div = lshr i32 4096, %b    ; must be exact otherwise we'd divide by zero
605  %div2 = udiv i32 %a, %div
606  ret i32 %div2
607; CHECK-LABEL: @test42(
608; CHECK-NEXT: lshr exact i32 4096, %b
609}
610
611define i32 @test43(i32 %a, i32 %b) nounwind {
612  %div = shl i32 4096, %b    ; must be exact otherwise we'd divide by zero
613  %div2 = udiv i32 %a, %div
614  ret i32 %div2
615; CHECK-LABEL: @test43(
616; CHECK-NEXT: add i32 %b, 12
617; CHECK-NEXT: lshr
618; CHECK-NEXT: ret
619}
620
621define i32 @test44(i32 %a) nounwind {
622  %y = shl nuw i32 %a, 1
623  %z = shl i32 %y, 4
624  ret i32 %z
625; CHECK-LABEL: @test44(
626; CHECK-NEXT: %y = shl i32 %a, 5
627; CHECK-NEXT: ret i32 %y
628}
629
630define i32 @test45(i32 %a) nounwind {
631  %y = lshr exact i32 %a, 1
632  %z = lshr i32 %y, 4
633  ret i32 %z
634; CHECK-LABEL: @test45(
635; CHECK-NEXT: %y = lshr i32 %a, 5
636; CHECK-NEXT: ret i32 %y
637}
638
639define i32 @test46(i32 %a) {
640  %y = ashr exact i32 %a, 3
641  %z = shl i32 %y, 1
642  ret i32 %z
643; CHECK-LABEL: @test46(
644; CHECK-NEXT: %z = ashr exact i32 %a, 2
645; CHECK-NEXT: ret i32 %z
646}
647
648define i32 @test47(i32 %a) {
649  %y = lshr exact i32 %a, 3
650  %z = shl i32 %y, 1
651  ret i32 %z
652; CHECK-LABEL: @test47(
653; CHECK-NEXT: %z = lshr exact i32 %a, 2
654; CHECK-NEXT: ret i32 %z
655}
656
657define i32 @test48(i32 %x) {
658  %A = lshr exact i32 %x, 1
659  %B = shl i32 %A, 3
660  ret i32 %B
661; CHECK-LABEL: @test48(
662; CHECK-NEXT: %B = shl i32 %x, 2
663; CHECK-NEXT: ret i32 %B
664}
665
666define i32 @test49(i32 %x) {
667  %A = ashr exact i32 %x, 1
668  %B = shl i32 %A, 3
669  ret i32 %B
670; CHECK-LABEL: @test49(
671; CHECK-NEXT: %B = shl i32 %x, 2
672; CHECK-NEXT: ret i32 %B
673}
674
675define i32 @test50(i32 %x) {
676  %A = shl nsw i32 %x, 1
677  %B = ashr i32 %A, 3
678  ret i32 %B
679; CHECK-LABEL: @test50(
680; CHECK-NEXT: %B = ashr i32 %x, 2
681; CHECK-NEXT: ret i32 %B
682}
683
684define i32 @test51(i32 %x) {
685  %A = shl nuw i32 %x, 1
686  %B = lshr i32 %A, 3
687  ret i32 %B
688; CHECK-LABEL: @test51(
689; CHECK-NEXT: %B = lshr i32 %x, 2
690; CHECK-NEXT: ret i32 %B
691}
692
693define i32 @test52(i32 %x) {
694  %A = shl nsw i32 %x, 3
695  %B = ashr i32 %A, 1
696  ret i32 %B
697; CHECK-LABEL: @test52(
698; CHECK-NEXT: %B = shl nsw i32 %x, 2
699; CHECK-NEXT: ret i32 %B
700}
701
702define i32 @test53(i32 %x) {
703  %A = shl nuw i32 %x, 3
704  %B = lshr i32 %A, 1
705  ret i32 %B
706; CHECK-LABEL: @test53(
707; CHECK-NEXT: %B = shl nuw i32 %x, 2
708; CHECK-NEXT: ret i32 %B
709}
710
711define i32 @test54(i32 %x) {
712  %shr2 = lshr i32 %x, 1
713  %shl = shl i32 %shr2, 4
714  %and = and i32 %shl, 16
715  ret i32 %and
716; CHECK-LABEL: @test54(
717; CHECK: shl i32 %x, 3
718}
719
720
721define i32 @test55(i32 %x) {
722  %shr2 = lshr i32 %x, 1
723  %shl = shl i32 %shr2, 4
724  %or = or i32 %shl, 8
725  ret i32 %or
726; CHECK-LABEL: @test55(
727; CHECK: shl i32 %x, 3
728}
729
730define i32 @test56(i32 %x) {
731  %shr2 = lshr i32 %x, 1
732  %shl = shl i32 %shr2, 4
733  %or = or i32 %shl, 7
734  ret i32 %or
735; CHECK-LABEL: @test56(
736; CHECK: shl i32 %shr2, 4
737}
738
739
740define i32 @test57(i32 %x) {
741  %shr = lshr i32 %x, 1
742  %shl = shl i32 %shr, 4
743  %and = and i32 %shl, 16
744  ret i32 %and
745; CHECK-LABEL: @test57(
746; CHECK: shl i32 %x, 3
747}
748
749define i32 @test58(i32 %x) {
750  %shr = lshr i32 %x, 1
751  %shl = shl i32 %shr, 4
752  %or = or i32 %shl, 8
753  ret i32 %or
754; CHECK-LABEL: @test58(
755; CHECK: shl i32 %x, 3
756}
757
758define i32 @test59(i32 %x) {
759  %shr = ashr i32 %x, 1
760  %shl = shl i32 %shr, 4
761  %or = or i32 %shl, 7
762  ret i32 %or
763; CHECK-LABEL: @test59(
764; CHECK: %shl = shl i32 %shr1, 4
765}
766
767
768define i32 @test60(i32 %x) {
769  %shr = ashr i32 %x, 4
770  %shl = shl i32 %shr, 1
771  %or = or i32 %shl, 1
772  ret i32 %or
773; CHECK-LABEL: @test60(
774; CHECK: ashr i32 %x, 3
775}
776
777
778define i32 @test61(i32 %x) {
779  %shr = ashr i32 %x, 4
780  %shl = shl i32 %shr, 1
781  %or = or i32 %shl, 2
782  ret i32 %or
783; CHECK-LABEL: @test61(
784; CHECK: ashr i32 %x, 4
785}
786
787; propagate "exact" trait
788define i32 @test62(i32 %x) {
789  %shr = ashr exact i32 %x, 4
790  %shl = shl i32 %shr, 1
791  %or = or i32 %shl, 1
792  ret i32 %or
793; CHECK-LABEL: @test62(
794; CHECK: ashr exact i32 %x, 3
795}
796
797; PR17026
798; CHECK-LABEL: @test63(
799; CHECK-NOT: sh
800; CHECK: ret
801define void @test63(i128 %arg) {
802bb:
803  br i1 undef, label %bb1, label %bb12
804
805bb1:                                              ; preds = %bb11, %bb
806  br label %bb2
807
808bb2:                                              ; preds = %bb7, %bb1
809  br i1 undef, label %bb3, label %bb7
810
811bb3:                                              ; preds = %bb2
812  %tmp = lshr i128 %arg, 36893488147419103232
813  %tmp4 = shl i128 %tmp, 0
814  %tmp5 = or i128 %tmp4, undef
815  %tmp6 = trunc i128 %tmp5 to i16
816  br label %bb8
817
818bb7:                                              ; preds = %bb2
819  br i1 undef, label %bb8, label %bb2
820
821bb8:                                              ; preds = %bb7, %bb3
822  %tmp9 = phi i16 [ %tmp6, %bb3 ], [ undef, %bb7 ]
823  %tmp10 = icmp eq i16 %tmp9, 0
824  br i1 %tmp10, label %bb11, label %bb12
825
826bb11:                                             ; preds = %bb8
827  br i1 undef, label %bb1, label %bb12
828
829bb12:                                             ; preds = %bb11, %bb8, %bb
830  ret void
831}
832
833define i32 @test64(i32 %a) {
834; CHECK-LABEL: @test64(
835; CHECK-NEXT: ret i32 undef
836  %b = ashr i32 %a, 32  ; shift all bits out
837  ret i32 %b
838}
839
840define <4 x i32> @test64_splat_vector(<4 x i32> %a) {
841; CHECK-LABEL: @test64_splat_vector
842; CHECK-NEXT: ret <4 x i32> undef
843  %b = ashr <4 x i32> %a, <i32 32, i32 32, i32 32, i32 32>  ; shift all bits out
844  ret <4 x i32> %b
845}
846
847define <4 x i32> @test64_non_splat_vector(<4 x i32> %a) {
848; CHECK-LABEL: @test64_non_splat_vector
849; CHECK-NOT: ret <4 x i32> undef
850  %b = ashr <4 x i32> %a, <i32 32, i32 0, i32 1, i32 2>  ; shift all bits out
851  ret <4 x i32> %b
852}
853
854define <2 x i65> @test_65(<2 x i64> %t) {
855; CHECK-LABEL: @test_65
856  %a = zext <2 x i64> %t to <2 x i65>
857  %sext = shl <2 x i65> %a, <i65 33, i65 33>
858  %b = ashr <2 x i65> %sext, <i65 33, i65 33>
859  ret <2 x i65> %b
860}
861