1; RUN: opt -S -basic-aa -dse -enable-dse-memoryssa=false < %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.p0i8(i64, i8* nocapture) nounwind 6declare void @llvm.lifetime.end.p0i8(i64, i8* nocapture) nounwind 7declare void @llvm.memset.p0i8.i8(i8* nocapture, i8, i8, 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.p0i8(i64 1, i8* %A) 15; CHECK-NOT: lifetime.end 16 17 call void @llvm.memset.p0i8.i8(i8* %A, i8 0, i8 -1, 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.p0i8(i64 4, i8* %R) 29 store i32 0, i32* %Q ;; This store is dead. 30; CHECK-NOT: store 31 call void @llvm.lifetime.end.p0i8(i64 4, i8* %R) 32 ret void 33} 34 35 36