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1; RUN: opt < %s -aa-pipeline=basic-aa -passes=gvn,instcombine -S | FileCheck %s2 3declare ptr @test(ptr nocapture)4 5define i32 @test2() {6; CHECK: ret i32 07 %P = alloca i328 %Q = call ptr @test(ptr %P)9 %a = load i32, ptr %P10 store i32 4, ptr %Q ;; cannot clobber P since it is nocapture.11 %b = load i32, ptr %P12 %c = sub i32 %a, %b13 ret i32 %c14}15 16declare void @test3(ptr %p, ptr %q) nounwind17 18define i32 @test4(ptr noalias nocapture %p) nounwind {19; CHECK: call void @test320; CHECK: store i32 0, ptr %p21; CHECK: store i32 1, ptr %x22; CHECK: %y = load i32, ptr %p23; CHECK: ret i32 %y24entry:25 %q = alloca ptr26 ; Here test3 might store %p to %q. This doesn't violate %p's nocapture27 ; attribute since the copy doesn't outlive the function.28 call void @test3(ptr %q, ptr %p) nounwind29 store i32 0, ptr %p30 %x = load ptr, ptr %q31 ; This store might write to %p and so we can't eliminate the subsequent32 ; load33 store i32 1, ptr %x34 %y = load i32, ptr %p35 ret i32 %y36}37