1 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
2 ; RUN: opt -instcombine -S < %s | FileCheck %s
4 ; This test is to verify that the instruction combiner is able to fold
5 ; a cttz/ctlz followed by a icmp + select into a single cttz/ctlz with
6 ; the 'is_zero_undef' flag cleared.
8 define i16 @test1(i16 %x) {
10 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i16 @llvm.ctlz.i16(i16 [[X:%.*]], i1 false), !range !0
11 ; CHECK-NEXT: ret i16 [[TMP1]]
13 %ct = tail call i16 @llvm.ctlz.i16(i16 %x, i1 true)
14 %tobool = icmp ne i16 %x, 0
15 %cond = select i1 %tobool, i16 %ct, i16 16
19 define i32 @test2(i32 %x) {
20 ; CHECK-LABEL: @test2(
21 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i32 @llvm.ctlz.i32(i32 [[X:%.*]], i1 false), !range !1
22 ; CHECK-NEXT: ret i32 [[TMP1]]
24 %ct = tail call i32 @llvm.ctlz.i32(i32 %x, i1 true)
25 %tobool = icmp ne i32 %x, 0
26 %cond = select i1 %tobool, i32 %ct, i32 32
30 define i64 @test3(i64 %x) {
31 ; CHECK-LABEL: @test3(
32 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i64 @llvm.ctlz.i64(i64 [[X:%.*]], i1 false), !range !2
33 ; CHECK-NEXT: ret i64 [[TMP1]]
35 %ct = tail call i64 @llvm.ctlz.i64(i64 %x, i1 true)
36 %tobool = icmp ne i64 %x, 0
37 %cond = select i1 %tobool, i64 %ct, i64 64
41 define i16 @test4(i16 %x) {
42 ; CHECK-LABEL: @test4(
43 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i16 @llvm.ctlz.i16(i16 [[X:%.*]], i1 false), !range !0
44 ; CHECK-NEXT: ret i16 [[TMP1]]
46 %ct = tail call i16 @llvm.ctlz.i16(i16 %x, i1 true)
47 %tobool = icmp eq i16 %x, 0
48 %cond = select i1 %tobool, i16 16, i16 %ct
52 define i32 @test5(i32 %x) {
53 ; CHECK-LABEL: @test5(
54 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i32 @llvm.ctlz.i32(i32 [[X:%.*]], i1 false), !range !1
55 ; CHECK-NEXT: ret i32 [[TMP1]]
57 %ct = tail call i32 @llvm.ctlz.i32(i32 %x, i1 true)
58 %tobool = icmp eq i32 %x, 0
59 %cond = select i1 %tobool, i32 32, i32 %ct
63 define i64 @test6(i64 %x) {
64 ; CHECK-LABEL: @test6(
65 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i64 @llvm.ctlz.i64(i64 [[X:%.*]], i1 false), !range !2
66 ; CHECK-NEXT: ret i64 [[TMP1]]
68 %ct = tail call i64 @llvm.ctlz.i64(i64 %x, i1 true)
69 %tobool = icmp eq i64 %x, 0
70 %cond = select i1 %tobool, i64 64, i64 %ct
74 define i16 @test1b(i16 %x) {
75 ; CHECK-LABEL: @test1b(
76 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i16 @llvm.cttz.i16(i16 [[X:%.*]], i1 false), !range !0
77 ; CHECK-NEXT: ret i16 [[TMP1]]
79 %ct = tail call i16 @llvm.cttz.i16(i16 %x, i1 true)
80 %tobool = icmp ne i16 %x, 0
81 %cond = select i1 %tobool, i16 %ct, i16 16
85 define i32 @test2b(i32 %x) {
86 ; CHECK-LABEL: @test2b(
87 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i32 @llvm.cttz.i32(i32 [[X:%.*]], i1 false), !range !1
88 ; CHECK-NEXT: ret i32 [[TMP1]]
90 %ct = tail call i32 @llvm.cttz.i32(i32 %x, i1 true)
91 %tobool = icmp ne i32 %x, 0
92 %cond = select i1 %tobool, i32 %ct, i32 32
96 define i64 @test3b(i64 %x) {
97 ; CHECK-LABEL: @test3b(
98 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i64 @llvm.cttz.i64(i64 [[X:%.*]], i1 false), !range !2
99 ; CHECK-NEXT: ret i64 [[TMP1]]
101 %ct = tail call i64 @llvm.cttz.i64(i64 %x, i1 true)
102 %tobool = icmp ne i64 %x, 0
103 %cond = select i1 %tobool, i64 %ct, i64 64
107 define i16 @test4b(i16 %x) {
108 ; CHECK-LABEL: @test4b(
109 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i16 @llvm.cttz.i16(i16 [[X:%.*]], i1 false), !range !0
110 ; CHECK-NEXT: ret i16 [[TMP1]]
112 %ct = tail call i16 @llvm.cttz.i16(i16 %x, i1 true)
113 %tobool = icmp eq i16 %x, 0
114 %cond = select i1 %tobool, i16 16, i16 %ct
118 define i32 @test5b(i32 %x) {
119 ; CHECK-LABEL: @test5b(
121 ; CHECK-NEXT: [[TMP0:%.*]] = tail call i32 @llvm.cttz.i32(i32 [[X:%.*]], i1 false), !range !1
122 ; CHECK-NEXT: ret i32 [[TMP0]]
125 %ct = tail call i32 @llvm.cttz.i32(i32 %x, i1 true)
126 %tobool = icmp eq i32 %x, 0
127 %cond = select i1 %tobool, i32 32, i32 %ct
131 define i64 @test6b(i64 %x) {
132 ; CHECK-LABEL: @test6b(
133 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i64 @llvm.cttz.i64(i64 [[X:%.*]], i1 false), !range !2
134 ; CHECK-NEXT: ret i64 [[TMP1]]
136 %ct = tail call i64 @llvm.cttz.i64(i64 %x, i1 true)
137 %tobool = icmp eq i64 %x, 0
138 %cond = select i1 %tobool, i64 64, i64 %ct
142 define i32 @test1c(i16 %x) {
143 ; CHECK-LABEL: @test1c(
144 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i16 @llvm.cttz.i16(i16 [[X:%.*]], i1 false), !range !0
145 ; CHECK-NEXT: [[TMP2:%.*]] = zext i16 [[TMP1]] to i32
146 ; CHECK-NEXT: ret i32 [[TMP2]]
148 %ct = tail call i16 @llvm.cttz.i16(i16 %x, i1 true)
149 %cast2 = zext i16 %ct to i32
150 %tobool = icmp ne i16 %x, 0
151 %cond = select i1 %tobool, i32 %cast2, i32 16
155 define i64 @test2c(i16 %x) {
156 ; CHECK-LABEL: @test2c(
157 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i16 @llvm.cttz.i16(i16 [[X:%.*]], i1 false), !range !0
158 ; CHECK-NEXT: [[TMP2:%.*]] = zext i16 [[TMP1]] to i64
159 ; CHECK-NEXT: ret i64 [[TMP2]]
161 %ct = tail call i16 @llvm.cttz.i16(i16 %x, i1 true)
162 %conv = zext i16 %ct to i64
163 %tobool = icmp ne i16 %x, 0
164 %cond = select i1 %tobool, i64 %conv, i64 16
168 define i64 @test3c(i32 %x) {
169 ; CHECK-LABEL: @test3c(
170 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i32 @llvm.cttz.i32(i32 [[X:%.*]], i1 false), !range !1
171 ; CHECK-NEXT: [[TMP2:%.*]] = zext i32 [[TMP1]] to i64
172 ; CHECK-NEXT: ret i64 [[TMP2]]
174 %ct = tail call i32 @llvm.cttz.i32(i32 %x, i1 true)
175 %conv = zext i32 %ct to i64
176 %tobool = icmp ne i32 %x, 0
177 %cond = select i1 %tobool, i64 %conv, i64 32
181 define i32 @test4c(i16 %x) {
182 ; CHECK-LABEL: @test4c(
183 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i16 @llvm.ctlz.i16(i16 [[X:%.*]], i1 false), !range !0
184 ; CHECK-NEXT: [[TMP2:%.*]] = zext i16 [[TMP1]] to i32
185 ; CHECK-NEXT: ret i32 [[TMP2]]
187 %ct = tail call i16 @llvm.ctlz.i16(i16 %x, i1 true)
188 %cast = zext i16 %ct to i32
189 %tobool = icmp ne i16 %x, 0
190 %cond = select i1 %tobool, i32 %cast, i32 16
194 define i64 @test5c(i16 %x) {
195 ; CHECK-LABEL: @test5c(
196 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i16 @llvm.ctlz.i16(i16 [[X:%.*]], i1 false), !range !0
197 ; CHECK-NEXT: [[TMP2:%.*]] = zext i16 [[TMP1]] to i64
198 ; CHECK-NEXT: ret i64 [[TMP2]]
200 %ct = tail call i16 @llvm.ctlz.i16(i16 %x, i1 true)
201 %cast = zext i16 %ct to i64
202 %tobool = icmp ne i16 %x, 0
203 %cond = select i1 %tobool, i64 %cast, i64 16
207 define i64 @test6c(i32 %x) {
208 ; CHECK-LABEL: @test6c(
209 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i32 @llvm.ctlz.i32(i32 [[X:%.*]], i1 false), !range !1
210 ; CHECK-NEXT: [[TMP2:%.*]] = zext i32 [[TMP1]] to i64
211 ; CHECK-NEXT: ret i64 [[TMP2]]
213 %ct = tail call i32 @llvm.ctlz.i32(i32 %x, i1 true)
214 %cast = zext i32 %ct to i64
215 %tobool = icmp ne i32 %x, 0
216 %cond = select i1 %tobool, i64 %cast, i64 32
220 define i16 @test1d(i64 %x) {
221 ; CHECK-LABEL: @test1d(
222 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i64 @llvm.cttz.i64(i64 [[X:%.*]], i1 false), !range !2
223 ; CHECK-NEXT: [[TMP2:%.*]] = trunc i64 [[TMP1]] to i16
224 ; CHECK-NEXT: ret i16 [[TMP2]]
226 %ct = tail call i64 @llvm.cttz.i64(i64 %x, i1 true)
227 %conv = trunc i64 %ct to i16
228 %tobool = icmp ne i64 %x, 0
229 %cond = select i1 %tobool, i16 %conv, i16 64
233 define i32 @test2d(i64 %x) {
234 ; CHECK-LABEL: @test2d(
235 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i64 @llvm.cttz.i64(i64 [[X:%.*]], i1 false), !range !2
236 ; CHECK-NEXT: [[TMP2:%.*]] = trunc i64 [[TMP1]] to i32
237 ; CHECK-NEXT: ret i32 [[TMP2]]
239 %ct = tail call i64 @llvm.cttz.i64(i64 %x, i1 true)
240 %cast = trunc i64 %ct to i32
241 %tobool = icmp ne i64 %x, 0
242 %cond = select i1 %tobool, i32 %cast, i32 64
246 define i16 @test3d(i32 %x) {
247 ; CHECK-LABEL: @test3d(
248 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i32 @llvm.cttz.i32(i32 [[X:%.*]], i1 false), !range !1
249 ; CHECK-NEXT: [[TMP2:%.*]] = trunc i32 [[TMP1]] to i16
250 ; CHECK-NEXT: ret i16 [[TMP2]]
252 %ct = tail call i32 @llvm.cttz.i32(i32 %x, i1 true)
253 %cast = trunc i32 %ct to i16
254 %tobool = icmp ne i32 %x, 0
255 %cond = select i1 %tobool, i16 %cast, i16 32
259 define i16 @test4d(i64 %x) {
260 ; CHECK-LABEL: @test4d(
261 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i64 @llvm.ctlz.i64(i64 [[X:%.*]], i1 false), !range !2
262 ; CHECK-NEXT: [[TMP2:%.*]] = trunc i64 [[TMP1]] to i16
263 ; CHECK-NEXT: ret i16 [[TMP2]]
265 %ct = tail call i64 @llvm.ctlz.i64(i64 %x, i1 true)
266 %cast = trunc i64 %ct to i16
267 %tobool = icmp ne i64 %x, 0
268 %cond = select i1 %tobool, i16 %cast, i16 64
272 define i32 @test5d(i64 %x) {
273 ; CHECK-LABEL: @test5d(
274 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i64 @llvm.ctlz.i64(i64 [[X:%.*]], i1 false), !range !2
275 ; CHECK-NEXT: [[TMP2:%.*]] = trunc i64 [[TMP1]] to i32
276 ; CHECK-NEXT: ret i32 [[TMP2]]
278 %ct = tail call i64 @llvm.ctlz.i64(i64 %x, i1 true)
279 %cast = trunc i64 %ct to i32
280 %tobool = icmp ne i64 %x, 0
281 %cond = select i1 %tobool, i32 %cast, i32 64
285 define i16 @test6d(i32 %x) {
286 ; CHECK-LABEL: @test6d(
287 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i32 @llvm.ctlz.i32(i32 [[X:%.*]], i1 false), !range !1
288 ; CHECK-NEXT: [[TMP2:%.*]] = trunc i32 [[TMP1]] to i16
289 ; CHECK-NEXT: ret i16 [[TMP2]]
291 %ct = tail call i32 @llvm.ctlz.i32(i32 %x, i1 true)
292 %cast = trunc i32 %ct to i16
293 %tobool = icmp ne i32 %x, 0
294 %cond = select i1 %tobool, i16 %cast, i16 32
298 define i64 @select_bug1(i32 %x) {
299 ; CHECK-LABEL: @select_bug1(
300 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i32 @llvm.cttz.i32(i32 [[X:%.*]], i1 false), !range !1
301 ; CHECK-NEXT: [[TMP2:%.*]] = zext i32 [[TMP1]] to i64
302 ; CHECK-NEXT: ret i64 [[TMP2]]
304 %ct = tail call i32 @llvm.cttz.i32(i32 %x, i1 false)
305 %conv = zext i32 %ct to i64
306 %tobool = icmp ne i32 %x, 0
307 %cond = select i1 %tobool, i64 %conv, i64 32
311 define i16 @select_bug2(i32 %x) {
312 ; CHECK-LABEL: @select_bug2(
313 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i32 @llvm.cttz.i32(i32 [[X:%.*]], i1 false), !range !1
314 ; CHECK-NEXT: [[TMP2:%.*]] = trunc i32 [[TMP1]] to i16
315 ; CHECK-NEXT: ret i16 [[TMP2]]
317 %ct = tail call i32 @llvm.cttz.i32(i32 %x, i1 false)
318 %conv = trunc i32 %ct to i16
319 %tobool = icmp ne i32 %x, 0
320 %cond = select i1 %tobool, i16 %conv, i16 32
324 define i128 @test7(i128 %x) {
325 ; CHECK-LABEL: @test7(
326 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i128 @llvm.ctlz.i128(i128 [[X:%.*]], i1 false), !range !3
327 ; CHECK-NEXT: ret i128 [[TMP1]]
329 %ct = tail call i128 @llvm.ctlz.i128(i128 %x, i1 true)
330 %tobool = icmp ne i128 %x, 0
331 %cond = select i1 %tobool, i128 %ct, i128 128
335 define i128 @test8(i128 %x) {
336 ; CHECK-LABEL: @test8(
337 ; CHECK-NEXT: [[TMP1:%.*]] = tail call i128 @llvm.cttz.i128(i128 [[X:%.*]], i1 false), !range !3
338 ; CHECK-NEXT: ret i128 [[TMP1]]
340 %ct = tail call i128 @llvm.cttz.i128(i128 %x, i1 true)
341 %tobool = icmp ne i128 %x, 0
342 %cond = select i1 %tobool, i128 %ct, i128 128
346 define i32 @test_ctlz_not_bw(i32 %x) {
347 ; CHECK-LABEL: @test_ctlz_not_bw(
348 ; CHECK-NEXT: [[CT:%.*]] = tail call i32 @llvm.ctlz.i32(i32 [[X:%.*]], i1 true), !range !1
349 ; CHECK-NEXT: [[CMP:%.*]] = icmp eq i32 [[X]], 0
350 ; CHECK-NEXT: [[RES:%.*]] = select i1 [[CMP]], i32 123, i32 [[CT]]
351 ; CHECK-NEXT: ret i32 [[RES]]
353 %ct = tail call i32 @llvm.ctlz.i32(i32 %x, i1 false)
354 %cmp = icmp ne i32 %x, 0
355 %res = select i1 %cmp, i32 %ct, i32 123
359 define i32 @test_ctlz_not_bw_multiuse(i32 %x) {
360 ; CHECK-LABEL: @test_ctlz_not_bw_multiuse(
361 ; CHECK-NEXT: [[CT:%.*]] = tail call i32 @llvm.ctlz.i32(i32 [[X:%.*]], i1 false), !range !1
362 ; CHECK-NEXT: [[CMP:%.*]] = icmp eq i32 [[X]], 0
363 ; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP]], i32 123, i32 [[CT]]
364 ; CHECK-NEXT: [[RES:%.*]] = or i32 [[SEL]], [[CT]]
365 ; CHECK-NEXT: ret i32 [[RES]]
367 %ct = tail call i32 @llvm.ctlz.i32(i32 %x, i1 false)
368 %cmp = icmp ne i32 %x, 0
369 %sel = select i1 %cmp, i32 %ct, i32 123
370 %res = or i32 %sel, %ct
374 define i32 @test_cttz_not_bw(i32 %x) {
375 ; CHECK-LABEL: @test_cttz_not_bw(
376 ; CHECK-NEXT: [[CT:%.*]] = tail call i32 @llvm.cttz.i32(i32 [[X:%.*]], i1 true), !range !1
377 ; CHECK-NEXT: [[CMP:%.*]] = icmp eq i32 [[X]], 0
378 ; CHECK-NEXT: [[RES:%.*]] = select i1 [[CMP]], i32 123, i32 [[CT]]
379 ; CHECK-NEXT: ret i32 [[RES]]
381 %ct = tail call i32 @llvm.cttz.i32(i32 %x, i1 false)
382 %cmp = icmp ne i32 %x, 0
383 %res = select i1 %cmp, i32 %ct, i32 123
387 define i32 @test_cttz_not_bw_multiuse(i32 %x) {
388 ; CHECK-LABEL: @test_cttz_not_bw_multiuse(
389 ; CHECK-NEXT: [[CT:%.*]] = tail call i32 @llvm.cttz.i32(i32 [[X:%.*]], i1 false), !range !1
390 ; CHECK-NEXT: [[CMP:%.*]] = icmp eq i32 [[X]], 0
391 ; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP]], i32 123, i32 [[CT]]
392 ; CHECK-NEXT: [[RES:%.*]] = or i32 [[SEL]], [[CT]]
393 ; CHECK-NEXT: ret i32 [[RES]]
395 %ct = tail call i32 @llvm.cttz.i32(i32 %x, i1 false)
396 %cmp = icmp ne i32 %x, 0
397 %sel = select i1 %cmp, i32 %ct, i32 123
398 %res = or i32 %sel, %ct
402 define <2 x i32> @test_ctlz_bw_vec(<2 x i32> %x) {
403 ; CHECK-LABEL: @test_ctlz_bw_vec(
404 ; CHECK-NEXT: [[TMP1:%.*]] = tail call <2 x i32> @llvm.ctlz.v2i32(<2 x i32> [[X:%.*]], i1 false)
405 ; CHECK-NEXT: ret <2 x i32> [[TMP1]]
407 %ct = tail call <2 x i32> @llvm.ctlz.v2i32(<2 x i32> %x, i1 true)
408 %cmp = icmp ne <2 x i32> %x, zeroinitializer
409 %res = select <2 x i1> %cmp, <2 x i32> %ct, <2 x i32> <i32 32, i32 32>
413 define <2 x i32> @test_ctlz_not_bw_vec(<2 x i32> %x) {
414 ; CHECK-LABEL: @test_ctlz_not_bw_vec(
415 ; CHECK-NEXT: [[CT:%.*]] = tail call <2 x i32> @llvm.ctlz.v2i32(<2 x i32> [[X:%.*]], i1 true)
416 ; CHECK-NEXT: [[CMP:%.*]] = icmp eq <2 x i32> [[X]], zeroinitializer
417 ; CHECK-NEXT: [[RES:%.*]] = select <2 x i1> [[CMP]], <2 x i32> zeroinitializer, <2 x i32> [[CT]]
418 ; CHECK-NEXT: ret <2 x i32> [[RES]]
420 %ct = tail call <2 x i32> @llvm.ctlz.v2i32(<2 x i32> %x, i1 false)
421 %cmp = icmp ne <2 x i32> %x, zeroinitializer
422 %res = select <2 x i1> %cmp, <2 x i32> %ct, <2 x i32> <i32 0, i32 0>
426 define <2 x i32> @test_cttz_bw_vec(<2 x i32> %x) {
427 ; CHECK-LABEL: @test_cttz_bw_vec(
428 ; CHECK-NEXT: [[TMP1:%.*]] = tail call <2 x i32> @llvm.cttz.v2i32(<2 x i32> [[X:%.*]], i1 false)
429 ; CHECK-NEXT: ret <2 x i32> [[TMP1]]
431 %ct = tail call <2 x i32> @llvm.cttz.v2i32(<2 x i32> %x, i1 true)
432 %cmp = icmp ne <2 x i32> %x, zeroinitializer
433 %res = select <2 x i1> %cmp, <2 x i32> %ct, <2 x i32> <i32 32, i32 32>
437 define <2 x i32> @test_cttz_not_bw_vec(<2 x i32> %x) {
438 ; CHECK-LABEL: @test_cttz_not_bw_vec(
439 ; CHECK-NEXT: [[CT:%.*]] = tail call <2 x i32> @llvm.cttz.v2i32(<2 x i32> [[X:%.*]], i1 true)
440 ; CHECK-NEXT: [[CMP:%.*]] = icmp eq <2 x i32> [[X]], zeroinitializer
441 ; CHECK-NEXT: [[RES:%.*]] = select <2 x i1> [[CMP]], <2 x i32> zeroinitializer, <2 x i32> [[CT]]
442 ; CHECK-NEXT: ret <2 x i32> [[RES]]
444 %ct = tail call <2 x i32> @llvm.cttz.v2i32(<2 x i32> %x, i1 false)
445 %cmp = icmp ne <2 x i32> %x, zeroinitializer
446 %res = select <2 x i1> %cmp, <2 x i32> %ct, <2 x i32> <i32 0, i32 0>
450 declare i16 @llvm.ctlz.i16(i16, i1)
451 declare i32 @llvm.ctlz.i32(i32, i1)
452 declare i64 @llvm.ctlz.i64(i64, i1)
453 declare i128 @llvm.ctlz.i128(i128, i1)
454 declare <2 x i32> @llvm.ctlz.v2i32(<2 x i32>, i1)
455 declare i16 @llvm.cttz.i16(i16, i1)
456 declare i32 @llvm.cttz.i32(i32, i1)
457 declare i64 @llvm.cttz.i64(i64, i1)
458 declare i128 @llvm.cttz.i128(i128, i1)
459 declare <2 x i32> @llvm.cttz.v2i32(<2 x i32>, i1)