1; RUN: opt < %s -basicaa -gvn -instcombine -S | FileCheck %s 2 3@flag0 = internal global i32 zeroinitializer 4@turn = internal global i32 zeroinitializer 5 6; CHECK: ret i32 0 7 8define i32 @main() { 9 %a = load i32, i32* @flag0 10 %b = atomicrmw xchg i32* @turn, i32 1 monotonic 11 %c = load i32, i32* @flag0 12 %d = sub i32 %a, %c 13 ret i32 %d 14} 15