1*9880d681SAndroid Build Coastguard Worker; RUN: opt < %s -basicaa -gvn -instcombine -S | FileCheck %s 2*9880d681SAndroid Build Coastguard Worker 3*9880d681SAndroid Build Coastguard Worker@flag0 = internal global i32 zeroinitializer 4*9880d681SAndroid Build Coastguard Worker@turn = internal global i32 zeroinitializer 5*9880d681SAndroid Build Coastguard Worker 6*9880d681SAndroid Build Coastguard Worker; CHECK: ret i32 0 7*9880d681SAndroid Build Coastguard Worker 8*9880d681SAndroid Build Coastguard Workerdefine i32 @main() { 9*9880d681SAndroid Build Coastguard Worker %a = load i32, i32* @flag0 10*9880d681SAndroid Build Coastguard Worker %b = atomicrmw xchg i32* @turn, i32 1 monotonic 11*9880d681SAndroid Build Coastguard Worker %c = load i32, i32* @flag0 12*9880d681SAndroid Build Coastguard Worker %d = sub i32 %a, %c 13*9880d681SAndroid Build Coastguard Worker ret i32 %d 14*9880d681SAndroid Build Coastguard Worker} 15