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1; RUN: opt -S -basicaa -dse < %s | FileCheck %s
2
3target datalayout = "E-p:64:64:64-a0:0:8-f32:32:32-f64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-v64:64:64-v128:128:128"
4
5declare void @llvm.lifetime.start(i64, i8* nocapture) nounwind
6declare void @llvm.lifetime.end(i64, i8* nocapture) nounwind
7declare void @llvm.memset.p0i8.i8(i8* nocapture, i8, i8, i32, i1) nounwind
8
9define void @test1() {
10; CHECK-LABEL: @test1(
11  %A = alloca i8
12
13  store i8 0, i8* %A  ;; Written to by memset
14  call void @llvm.lifetime.end(i64 1, i8* %A)
15; CHECK: lifetime.end
16
17  call void @llvm.memset.p0i8.i8(i8* %A, i8 0, i8 -1, i32 0, i1 false)
18; CHECK-NOT: memset
19
20  ret void
21; CHECK: ret void
22}
23
24define void @test2(i32* %P) {
25; CHECK: test2
26  %Q = getelementptr i32, i32* %P, i32 1
27  %R = bitcast i32* %Q to i8*
28  call void @llvm.lifetime.start(i64 4, i8* %R)
29; CHECK: lifetime.start
30  store i32 0, i32* %Q  ;; This store is dead.
31; CHECK-NOT: store
32  call void @llvm.lifetime.end(i64 4, i8* %R)
33; CHECK: lifetime.end
34  ret void
35}
36
37
38