; RUN: opt < %s -basicaa -gvn -instcombine -S | FileCheck %s declare i32* @test(i32* nocapture) define i32 @test2() { ; CHECK: ret i32 0 %P = alloca i32 %Q = call i32* @test(i32* %P) %a = load i32* %P store i32 4, i32* %Q ;; cannot clobber P since it is nocapture. %b = load i32* %P %c = sub i32 %a, %b ret i32 %c } declare void @test3(i32** %p, i32* %q) nounwind define i32 @test4(i32* noalias nocapture %p) nounwind { ; CHECK: call void @test3 ; CHECK: store i32 0, i32* %p ; CHECK: store i32 1, i32* %x ; CHECK: %y = load i32* %p ; CHECK: ret i32 %y entry: %q = alloca i32* ; Here test3 might store %p to %q. This doesn't violate %p's nocapture ; attribute since the copy doesn't outlive the function. call void @test3(i32** %q, i32* %p) nounwind store i32 0, i32* %p %x = load i32** %q ; This store might write to %p and so we can't eliminate the subsequent ; load store i32 1, i32* %x %y = load i32* %p ret i32 %y }