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1; RUN: opt -basicaa -loop-idiom < %s -S | FileCheck %s
2target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
3
4; For @test11_pattern
5; CHECK: @.memset_pattern = private unnamed_addr constant [4 x i32] [i32 1, i32 1, i32 1, i32 1]
6
7; For @test13_pattern
8; CHECK: @.memset_pattern.1 = private unnamed_addr constant [2 x i32*] [i32* @G, i32* @G]
9
10target triple = "x86_64-apple-darwin10.0.0"
11
12define void @test1(i8* %Base, i64 %Size) nounwind ssp {
13bb.nph:                                           ; preds = %entry
14  br label %for.body
15
16for.body:                                         ; preds = %bb.nph, %for.body
17  %indvar = phi i64 [ 0, %bb.nph ], [ %indvar.next, %for.body ]
18  %I.0.014 = getelementptr i8, i8* %Base, i64 %indvar
19  store i8 0, i8* %I.0.014, align 1
20  %indvar.next = add i64 %indvar, 1
21  %exitcond = icmp eq i64 %indvar.next, %Size
22  br i1 %exitcond, label %for.end, label %for.body
23
24for.end:                                          ; preds = %for.body, %entry
25  ret void
26; CHECK-LABEL: @test1(
27; CHECK: call void @llvm.memset.p0i8.i64(i8* %Base, i8 0, i64 %Size, i32 1, i1 false)
28; CHECK-NOT: store
29}
30
31; This is a loop that was rotated but where the blocks weren't merged.  This
32; shouldn't perturb us.
33define void @test1a(i8* %Base, i64 %Size) nounwind ssp {
34bb.nph:                                           ; preds = %entry
35  br label %for.body
36
37for.body:                                         ; preds = %bb.nph, %for.body
38  %indvar = phi i64 [ 0, %bb.nph ], [ %indvar.next, %for.body.cont ]
39  %I.0.014 = getelementptr i8, i8* %Base, i64 %indvar
40  store i8 0, i8* %I.0.014, align 1
41  %indvar.next = add i64 %indvar, 1
42  br label %for.body.cont
43for.body.cont:
44  %exitcond = icmp eq i64 %indvar.next, %Size
45  br i1 %exitcond, label %for.end, label %for.body
46
47for.end:                                          ; preds = %for.body, %entry
48  ret void
49; CHECK-LABEL: @test1a(
50; CHECK: call void @llvm.memset.p0i8.i64(i8* %Base, i8 0, i64 %Size, i32 1, i1 false)
51; CHECK-NOT: store
52}
53
54
55define void @test2(i32* %Base, i64 %Size) nounwind ssp {
56entry:
57  %cmp10 = icmp eq i64 %Size, 0
58  br i1 %cmp10, label %for.end, label %for.body
59
60for.body:                                         ; preds = %entry, %for.body
61  %i.011 = phi i64 [ %inc, %for.body ], [ 0, %entry ]
62  %add.ptr.i = getelementptr i32, i32* %Base, i64 %i.011
63  store i32 16843009, i32* %add.ptr.i, align 4
64  %inc = add nsw i64 %i.011, 1
65  %exitcond = icmp eq i64 %inc, %Size
66  br i1 %exitcond, label %for.end, label %for.body
67
68for.end:                                          ; preds = %for.body, %entry
69  ret void
70; CHECK-LABEL: @test2(
71; CHECK: br i1 %cmp10,
72; CHECK: %0 = shl i64 %Size, 2
73; CHECK: call void @llvm.memset.p0i8.i64(i8* %Base1, i8 1, i64 %0, i32 4, i1 false)
74; CHECK-NOT: store
75}
76
77; This is a case where there is an extra may-aliased store in the loop, we can't
78; promote the memset.
79define void @test3(i32* %Base, i64 %Size, i8 *%MayAlias) nounwind ssp {
80entry:
81  br label %for.body
82
83for.body:                                         ; preds = %entry, %for.body
84  %i.011 = phi i64 [ %inc, %for.body ], [ 0, %entry ]
85  %add.ptr.i = getelementptr i32, i32* %Base, i64 %i.011
86  store i32 16843009, i32* %add.ptr.i, align 4
87
88  store i8 42, i8* %MayAlias
89  %inc = add nsw i64 %i.011, 1
90  %exitcond = icmp eq i64 %inc, %Size
91  br i1 %exitcond, label %for.end, label %for.body
92
93for.end:                                          ; preds = %entry
94  ret void
95; CHECK-LABEL: @test3(
96; CHECK-NOT: memset
97; CHECK: ret void
98}
99
100
101;; TODO: We should be able to promote this memset.  Not yet though.
102define void @test4(i8* %Base) nounwind ssp {
103bb.nph:                                           ; preds = %entry
104  %Base100 = getelementptr i8, i8* %Base, i64 1000
105  br label %for.body
106
107for.body:                                         ; preds = %bb.nph, %for.body
108  %indvar = phi i64 [ 0, %bb.nph ], [ %indvar.next, %for.body ]
109  %I.0.014 = getelementptr i8, i8* %Base, i64 %indvar
110  store i8 0, i8* %I.0.014, align 1
111
112  ;; Store beyond the range memset, should be safe to promote.
113  store i8 42, i8* %Base100
114
115  %indvar.next = add i64 %indvar, 1
116  %exitcond = icmp eq i64 %indvar.next, 100
117  br i1 %exitcond, label %for.end, label %for.body
118
119for.end:                                          ; preds = %for.body, %entry
120  ret void
121; CHECK-TODO-LABEL: @test4(
122; CHECK-TODO: call void @llvm.memset.p0i8.i64(i8* %Base, i8 0, i64 100, i32 1, i1 false)
123; CHECK-TODO-NOT: store
124}
125
126; This can't be promoted: the memset is a store of a loop variant value.
127define void @test5(i8* %Base, i64 %Size) nounwind ssp {
128bb.nph:                                           ; preds = %entry
129  br label %for.body
130
131for.body:                                         ; preds = %bb.nph, %for.body
132  %indvar = phi i64 [ 0, %bb.nph ], [ %indvar.next, %for.body ]
133  %I.0.014 = getelementptr i8, i8* %Base, i64 %indvar
134
135  %V = trunc i64 %indvar to i8
136  store i8 %V, i8* %I.0.014, align 1
137  %indvar.next = add i64 %indvar, 1
138  %exitcond = icmp eq i64 %indvar.next, %Size
139  br i1 %exitcond, label %for.end, label %for.body
140
141for.end:                                          ; preds = %for.body, %entry
142  ret void
143; CHECK-LABEL: @test5(
144; CHECK-NOT: memset
145; CHECK: ret void
146}
147
148
149;; memcpy formation
150define void @test6(i64 %Size) nounwind ssp {
151bb.nph:
152  %Base = alloca i8, i32 10000
153  %Dest = alloca i8, i32 10000
154  br label %for.body
155
156for.body:                                         ; preds = %bb.nph, %for.body
157  %indvar = phi i64 [ 0, %bb.nph ], [ %indvar.next, %for.body ]
158  %I.0.014 = getelementptr i8, i8* %Base, i64 %indvar
159  %DestI = getelementptr i8, i8* %Dest, i64 %indvar
160  %V = load i8, i8* %I.0.014, align 1
161  store i8 %V, i8* %DestI, align 1
162  %indvar.next = add i64 %indvar, 1
163  %exitcond = icmp eq i64 %indvar.next, %Size
164  br i1 %exitcond, label %for.end, label %for.body
165
166for.end:                                          ; preds = %for.body, %entry
167  ret void
168; CHECK-LABEL: @test6(
169; CHECK: call void @llvm.memcpy.p0i8.p0i8.i64(i8* %Dest, i8* %Base, i64 %Size, i32 1, i1 false)
170; CHECK-NOT: store
171; CHECK: ret void
172}
173
174
175; This is a loop that was rotated but where the blocks weren't merged.  This
176; shouldn't perturb us.
177define void @test7(i8* %Base, i64 %Size) nounwind ssp {
178bb.nph:                                           ; preds = %entry
179  br label %for.body
180
181for.body:                                         ; preds = %bb.nph, %for.body
182  %indvar = phi i64 [ 0, %bb.nph ], [ %indvar.next, %for.body.cont ]
183  br label %for.body.cont
184for.body.cont:
185  %I.0.014 = getelementptr i8, i8* %Base, i64 %indvar
186  store i8 0, i8* %I.0.014, align 1
187  %indvar.next = add i64 %indvar, 1
188  %exitcond = icmp eq i64 %indvar.next, %Size
189  br i1 %exitcond, label %for.end, label %for.body
190
191for.end:                                          ; preds = %for.body, %entry
192  ret void
193; CHECK-LABEL: @test7(
194; CHECK: call void @llvm.memset.p0i8.i64(i8* %Base, i8 0, i64 %Size, i32 1, i1 false)
195; CHECK-NOT: store
196}
197
198; This is a loop should not be transformed, it only executes one iteration.
199define void @test8(i64* %Ptr, i64 %Size) nounwind ssp {
200bb.nph:                                           ; preds = %entry
201  br label %for.body
202
203for.body:                                         ; preds = %bb.nph, %for.body
204  %indvar = phi i64 [ 0, %bb.nph ], [ %indvar.next, %for.body ]
205  %PI = getelementptr i64, i64* %Ptr, i64 %indvar
206  store i64 0, i64 *%PI
207  %indvar.next = add i64 %indvar, 1
208  %exitcond = icmp eq i64 %indvar.next, 1
209  br i1 %exitcond, label %for.end, label %for.body
210
211for.end:                                          ; preds = %for.body, %entry
212  ret void
213; CHECK-LABEL: @test8(
214; CHECK: store i64 0, i64* %PI
215}
216
217declare i8* @external(i8*)
218
219;; This cannot be transformed into a memcpy, because the read-from location is
220;; mutated by the loop.
221define void @test9(i64 %Size) nounwind ssp {
222bb.nph:
223  %Base = alloca i8, i32 10000
224  %Dest = alloca i8, i32 10000
225
226  %BaseAlias = call i8* @external(i8* %Base)
227  br label %for.body
228
229for.body:                                         ; preds = %bb.nph, %for.body
230  %indvar = phi i64 [ 0, %bb.nph ], [ %indvar.next, %for.body ]
231  %I.0.014 = getelementptr i8, i8* %Base, i64 %indvar
232  %DestI = getelementptr i8, i8* %Dest, i64 %indvar
233  %V = load i8, i8* %I.0.014, align 1
234  store i8 %V, i8* %DestI, align 1
235
236  ;; This store can clobber the input.
237  store i8 4, i8* %BaseAlias
238
239  %indvar.next = add i64 %indvar, 1
240  %exitcond = icmp eq i64 %indvar.next, %Size
241  br i1 %exitcond, label %for.end, label %for.body
242
243for.end:                                          ; preds = %for.body, %entry
244  ret void
245; CHECK-LABEL: @test9(
246; CHECK-NOT: llvm.memcpy
247; CHECK: ret void
248}
249
250; Two dimensional nested loop should be promoted to one big memset.
251define void @test10(i8* %X) nounwind ssp {
252entry:
253  br label %bb.nph
254
255bb.nph:                                           ; preds = %entry, %for.inc10
256  %i.04 = phi i32 [ 0, %entry ], [ %inc12, %for.inc10 ]
257  br label %for.body5
258
259for.body5:                                        ; preds = %for.body5, %bb.nph
260  %j.02 = phi i32 [ 0, %bb.nph ], [ %inc, %for.body5 ]
261  %mul = mul nsw i32 %i.04, 100
262  %add = add nsw i32 %j.02, %mul
263  %idxprom = sext i32 %add to i64
264  %arrayidx = getelementptr inbounds i8, i8* %X, i64 %idxprom
265  store i8 0, i8* %arrayidx, align 1
266  %inc = add nsw i32 %j.02, 1
267  %cmp4 = icmp eq i32 %inc, 100
268  br i1 %cmp4, label %for.inc10, label %for.body5
269
270for.inc10:                                        ; preds = %for.body5
271  %inc12 = add nsw i32 %i.04, 1
272  %cmp = icmp eq i32 %inc12, 100
273  br i1 %cmp, label %for.end13, label %bb.nph
274
275for.end13:                                        ; preds = %for.inc10
276  ret void
277; CHECK-LABEL: @test10(
278; CHECK: entry:
279; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* %X, i8 0, i64 10000, i32 1, i1 false)
280; CHECK-NOT: store
281; CHECK: ret void
282}
283
284; On darwin10 (which is the triple in this .ll file) this loop can be turned
285; into a memset_pattern call.
286; rdar://9009151
287define void @test11_pattern(i32* nocapture %P) nounwind ssp {
288entry:
289  br label %for.body
290
291for.body:                                         ; preds = %entry, %for.body
292  %indvar = phi i64 [ 0, %entry ], [ %indvar.next, %for.body ]
293  %arrayidx = getelementptr i32, i32* %P, i64 %indvar
294  store i32 1, i32* %arrayidx, align 4
295  %indvar.next = add i64 %indvar, 1
296  %exitcond = icmp eq i64 %indvar.next, 10000
297  br i1 %exitcond, label %for.end, label %for.body
298
299for.end:                                          ; preds = %for.body
300  ret void
301; CHECK-LABEL: @test11_pattern(
302; CHECK-NEXT: entry:
303; CHECK-NEXT: bitcast
304; CHECK-NEXT: memset_pattern
305; CHECK-NOT: store
306; CHECK: ret void
307}
308
309; Store of null should turn into memset of zero.
310define void @test12(i32** nocapture %P) nounwind ssp {
311entry:
312  br label %for.body
313
314for.body:                                         ; preds = %entry, %for.body
315  %indvar = phi i64 [ 0, %entry ], [ %indvar.next, %for.body ]
316  %arrayidx = getelementptr i32*, i32** %P, i64 %indvar
317  store i32* null, i32** %arrayidx, align 4
318  %indvar.next = add i64 %indvar, 1
319  %exitcond = icmp eq i64 %indvar.next, 10000
320  br i1 %exitcond, label %for.end, label %for.body
321
322for.end:                                          ; preds = %for.body
323  ret void
324; CHECK-LABEL: @test12(
325; CHECK-NEXT: entry:
326; CHECK-NEXT: bitcast
327; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* %P1, i8 0, i64 80000, i32 4, i1 false)
328; CHECK-NOT: store
329; CHECK: ret void
330}
331
332@G = global i32 5
333
334; This store-of-address loop can be turned into a memset_pattern call.
335; rdar://9009151
336define void @test13_pattern(i32** nocapture %P) nounwind ssp {
337entry:
338  br label %for.body
339
340for.body:                                         ; preds = %entry, %for.body
341  %indvar = phi i64 [ 0, %entry ], [ %indvar.next, %for.body ]
342  %arrayidx = getelementptr i32*, i32** %P, i64 %indvar
343  store i32* @G, i32** %arrayidx, align 4
344  %indvar.next = add i64 %indvar, 1
345  %exitcond = icmp eq i64 %indvar.next, 10000
346  br i1 %exitcond, label %for.end, label %for.body
347
348for.end:                                          ; preds = %for.body
349  ret void
350; CHECK-LABEL: @test13_pattern(
351; CHECK-NEXT: entry:
352; CHECK-NEXT: bitcast
353; CHECK-NEXT: memset_pattern
354; CHECK-NOT: store
355; CHECK: ret void
356}
357
358
359
360; PR9815 - This is a partial overlap case that cannot be safely transformed
361; into a memcpy.
362@g_50 = global [7 x i32] [i32 0, i32 0, i32 0, i32 0, i32 1, i32 0, i32 0], align 16
363
364define i32 @test14() nounwind {
365entry:
366  br label %for.body
367
368for.body:                                         ; preds = %for.inc, %for.body.lr.ph
369  %tmp5 = phi i32 [ %inc, %for.body ], [ 0, %entry ]
370  %add = add nsw i32 %tmp5, 4
371  %idxprom = sext i32 %add to i64
372  %arrayidx = getelementptr inbounds [7 x i32], [7 x i32]* @g_50, i32 0, i64 %idxprom
373  %tmp2 = load i32, i32* %arrayidx, align 4
374  %add4 = add nsw i32 %tmp5, 5
375  %idxprom5 = sext i32 %add4 to i64
376  %arrayidx6 = getelementptr inbounds [7 x i32], [7 x i32]* @g_50, i32 0, i64 %idxprom5
377  store i32 %tmp2, i32* %arrayidx6, align 4
378  %inc = add nsw i32 %tmp5, 1
379  %cmp = icmp slt i32 %inc, 2
380  br i1 %cmp, label %for.body, label %for.end
381
382for.end:                                          ; preds = %for.inc
383  %tmp8 = load i32, i32* getelementptr inbounds ([7 x i32], [7 x i32]* @g_50, i32 0, i64 6), align 4
384  ret i32 %tmp8
385; CHECK-LABEL: @test14(
386; CHECK: for.body:
387; CHECK: load i32
388; CHECK: store i32
389; CHECK: br i1 %cmp
390
391}
392
393define void @PR14241(i32* %s, i64 %size) {
394; Ensure that we don't form a memcpy for strided loops. Briefly, when we taught
395; LoopIdiom about memmove and strided loops, this got miscompiled into a memcpy
396; instead of a memmove. If we get the memmove transform back, this will catch
397; regressions.
398;
399; CHECK-LABEL: @PR14241(
400
401entry:
402  %end.idx = add i64 %size, -1
403  %end.ptr = getelementptr inbounds i32, i32* %s, i64 %end.idx
404  br label %while.body
405; CHECK-NOT: memcpy
406;
407; FIXME: When we regain the ability to form a memmove here, this test should be
408; reversed and turned into a positive assertion.
409; CHECK-NOT: memmove
410
411while.body:
412  %phi.ptr = phi i32* [ %s, %entry ], [ %next.ptr, %while.body ]
413  %src.ptr = getelementptr inbounds i32, i32* %phi.ptr, i64 1
414  %val = load i32, i32* %src.ptr, align 4
415; CHECK: load
416  %dst.ptr = getelementptr inbounds i32, i32* %phi.ptr, i64 0
417  store i32 %val, i32* %dst.ptr, align 4
418; CHECK: store
419  %next.ptr = getelementptr inbounds i32, i32* %phi.ptr, i64 1
420  %cmp = icmp eq i32* %next.ptr, %end.ptr
421  br i1 %cmp, label %exit, label %while.body
422
423exit:
424  ret void
425; CHECK: ret void
426}
427
428; Recognize loops with a negative stride.
429define void @test15(i32* nocapture %f) {
430entry:
431  br label %for.body
432
433for.body:
434  %indvars.iv = phi i64 [ 65536, %entry ], [ %indvars.iv.next, %for.body ]
435  %arrayidx = getelementptr inbounds i32, i32* %f, i64 %indvars.iv
436  store i32 0, i32* %arrayidx, align 4
437  %indvars.iv.next = add nsw i64 %indvars.iv, -1
438  %cmp = icmp sgt i64 %indvars.iv, 0
439  br i1 %cmp, label %for.body, label %for.cond.cleanup
440
441for.cond.cleanup:
442  ret void
443; CHECK-LABEL: @test15(
444; CHECK: call void @llvm.memset.p0i8.i64(i8* %f1, i8 0, i64 262148, i32 4, i1 false)
445; CHECK-NOT: store
446; CHECK: ret void
447}
448
449; Loop with a negative stride.  Verify an aliasing write to f[65536] prevents
450; the creation of a memset.
451define void @test16(i32* nocapture %f) {
452entry:
453  %arrayidx1 = getelementptr inbounds i32, i32* %f, i64 65536
454  br label %for.body
455
456for.body:                                         ; preds = %entry, %for.body
457  %indvars.iv = phi i64 [ 65536, %entry ], [ %indvars.iv.next, %for.body ]
458  %arrayidx = getelementptr inbounds i32, i32* %f, i64 %indvars.iv
459  store i32 0, i32* %arrayidx, align 4
460  store i32 1, i32* %arrayidx1, align 4
461  %indvars.iv.next = add nsw i64 %indvars.iv, -1
462  %cmp = icmp sgt i64 %indvars.iv, 0
463  br i1 %cmp, label %for.body, label %for.cond.cleanup
464
465for.cond.cleanup:                                 ; preds = %for.body
466  ret void
467; CHECK-LABEL: @test16(
468; CHECK-NOT: call void @llvm.memset.p0i8.i64
469; CHECK: ret void
470}
471
472; Handle memcpy-able loops with negative stride.
473define noalias i32* @test17(i32* nocapture readonly %a, i32 %c) {
474entry:
475  %conv = sext i32 %c to i64
476  %mul = shl nsw i64 %conv, 2
477  %call = tail call noalias i8* @malloc(i64 %mul)
478  %0 = bitcast i8* %call to i32*
479  %tobool.9 = icmp eq i32 %c, 0
480  br i1 %tobool.9, label %while.end, label %while.body.preheader
481
482while.body.preheader:                             ; preds = %entry
483  br label %while.body
484
485while.body:                                       ; preds = %while.body.preheader, %while.body
486  %dec10.in = phi i32 [ %dec10, %while.body ], [ %c, %while.body.preheader ]
487  %dec10 = add nsw i32 %dec10.in, -1
488  %idxprom = sext i32 %dec10 to i64
489  %arrayidx = getelementptr inbounds i32, i32* %a, i64 %idxprom
490  %1 = load i32, i32* %arrayidx, align 4
491  %arrayidx2 = getelementptr inbounds i32, i32* %0, i64 %idxprom
492  store i32 %1, i32* %arrayidx2, align 4
493  %tobool = icmp eq i32 %dec10, 0
494  br i1 %tobool, label %while.end.loopexit, label %while.body
495
496while.end.loopexit:                               ; preds = %while.body
497  br label %while.end
498
499while.end:                                        ; preds = %while.end.loopexit, %entry
500  ret i32* %0
501; CHECK-LABEL: @test17(
502; CHECK: call void @llvm.memcpy
503; CHECK: ret i32*
504}
505
506declare noalias i8* @malloc(i64)
507
508; Handle memcpy-able loops with negative stride.
509; void test18(unsigned *__restrict__ a, unsigned *__restrict__ b) {
510;   for (int i = 2047; i >= 0; --i) {
511;     a[i] = b[i];
512;   }
513; }
514define void @test18(i32* noalias nocapture %a, i32* noalias nocapture readonly %b) #0 {
515entry:
516  br label %for.body
517
518for.body:                                         ; preds = %entry, %for.body
519  %indvars.iv = phi i64 [ 2047, %entry ], [ %indvars.iv.next, %for.body ]
520  %arrayidx = getelementptr inbounds i32, i32* %b, i64 %indvars.iv
521  %0 = load i32, i32* %arrayidx, align 4
522  %arrayidx2 = getelementptr inbounds i32, i32* %a, i64 %indvars.iv
523  store i32 %0, i32* %arrayidx2, align 4
524  %indvars.iv.next = add nsw i64 %indvars.iv, -1
525  %cmp = icmp sgt i64 %indvars.iv, 0
526  br i1 %cmp, label %for.body, label %for.cond.cleanup
527
528for.cond.cleanup:                                 ; preds = %for.body
529  ret void
530; CHECK-LABEL: @test18(
531; CHECK: call void @llvm.memcpy
532; CHECK: ret
533}
534
535; Two dimensional nested loop with negative stride should be promoted to one big memset.
536define void @test19(i8* nocapture %X) {
537entry:
538  br label %for.cond1.preheader
539
540for.cond1.preheader:                              ; preds = %entry, %for.inc4
541  %i.06 = phi i32 [ 99, %entry ], [ %dec5, %for.inc4 ]
542  %mul = mul nsw i32 %i.06, 100
543  br label %for.body3
544
545for.body3:                                        ; preds = %for.cond1.preheader, %for.body3
546  %j.05 = phi i32 [ 99, %for.cond1.preheader ], [ %dec, %for.body3 ]
547  %add = add nsw i32 %j.05, %mul
548  %idxprom = sext i32 %add to i64
549  %arrayidx = getelementptr inbounds i8, i8* %X, i64 %idxprom
550  store i8 0, i8* %arrayidx, align 1
551  %dec = add nsw i32 %j.05, -1
552  %cmp2 = icmp sgt i32 %j.05, 0
553  br i1 %cmp2, label %for.body3, label %for.inc4
554
555for.inc4:                                         ; preds = %for.body3
556  %dec5 = add nsw i32 %i.06, -1
557  %cmp = icmp sgt i32 %i.06, 0
558  br i1 %cmp, label %for.cond1.preheader, label %for.end6
559
560for.end6:                                         ; preds = %for.inc4
561  ret void
562; CHECK-LABEL: @test19(
563; CHECK: entry:
564; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* %X, i8 0, i64 10000, i32 1, i1 false)
565; CHECK: ret void
566}
567
568; Validate that "memset_pattern" has the proper attributes.
569; CHECK: declare void @memset_pattern16(i8* nocapture, i8* nocapture readonly, i64) [[ATTRS:#[0-9]+]]
570; CHECK: [[ATTRS]] = { argmemonly }
571