; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc < %s -mtriple=x86_64-apple-darwin | FileCheck %s

@val = internal global i64 0
@"\01LC" = internal constant [7 x i8] c"0x%lx\0A\00"

define i32 @main() nounwind {
; CHECK-LABEL: main:
; CHECK:       ## %bb.0: ## %entry
; CHECK-NEXT:    pushq %rax
; CHECK-NEXT:    movl $1, %ecx
; CHECK-NEXT:    xorl %eax, %eax
; CHECK-NEXT:    lock cmpxchgq %rcx, _val(%rip)
; CHECK-NEXT:    leaq LC(%rip), %rdi
; CHECK-NEXT:    movq %rax, %rsi
; CHECK-NEXT:    xorl %eax, %eax
; CHECK-NEXT:    callq _printf
; CHECK-NEXT:    xorl %eax, %eax
; CHECK-NEXT:    popq %rcx
; CHECK-NEXT:    retq
entry:
  %t0 = cmpxchg ptr @val, i64 0, i64 1 monotonic monotonic
  %0 = extractvalue { i64, i1 } %t0, 0
  %1 = tail call i32 (ptr, ...) @printf(ptr @"\01LC", i64 %0) nounwind
  ret i32 0
}

declare i32 @printf(ptr, ...) nounwind