38 lines
1019 B
LLVM
38 lines
1019 B
LLVM
; RUN: opt -S -basicaa -dse < %s | FileCheck %s
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target 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"
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declare void @llvm.lifetime.start(i64, i8* nocapture) nounwind
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declare void @llvm.lifetime.end(i64, i8* nocapture) nounwind
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declare void @llvm.memset.p0i8.i8(i8* nocapture, i8, i8, i32, i1) nounwind
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define void @test1() {
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; CHECK-LABEL: @test1(
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%A = alloca i8
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store i8 0, i8* %A ;; Written to by memset
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call void @llvm.lifetime.end(i64 1, i8* %A)
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; CHECK: lifetime.end
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call void @llvm.memset.p0i8.i8(i8* %A, i8 0, i8 -1, i32 0, i1 false)
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; CHECK-NOT: memset
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ret void
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; CHECK: ret void
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}
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define void @test2(i32* %P) {
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; CHECK: test2
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%Q = getelementptr i32, i32* %P, i32 1
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%R = bitcast i32* %Q to i8*
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call void @llvm.lifetime.start(i64 4, i8* %R)
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; CHECK: lifetime.start
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store i32 0, i32* %Q ;; This store is dead.
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; CHECK-NOT: store
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call void @llvm.lifetime.end(i64 4, i8* %R)
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; CHECK: lifetime.end
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ret void
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}
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