third_party/llvm-7.0/llvm/test/Analysis/BasicAA/tailcall-modref.ll

; RUN: opt < %s -basicaa -gvn -instcombine -S | FileCheck %s

define i32 @test() {
; CHECK: ret i32 0
        %A = alloca i32         ; <i32*> [#uses=3]
        call void @foo( i32* %A )
        %X = load i32, i32* %A               ; <i32> [#uses=1]
        tail call void @bar( )
        %Y = load i32, i32* %A               ; <i32> [#uses=1]
        %Z = sub i32 %X, %Y             ; <i32> [#uses=1]
        ret i32 %Z
}

declare void @foo(i32*)

declare void @bar()