1 volatile int x;
2 
3 void __attribute__((noinline)) sink() {
4   x++; //% self.filecheck("bt", "main.cpp", "-implicit-check-not=artificial")
5   // CHECK: frame #0: 0x{{[0-9a-f]+}} a.out`sink() at main.cpp:[[@LINE-1]]:4
6   // CHECK-NEXT: frame #1: 0x{{[0-9a-f]+}} a.out`func3() at main.cpp:16:3
7   // CHECK-SAME: [artificial]
8   // CHECK-NEXT: frame #2: 0x{{[0-9a-f]+}} a.out`func2()
9   // CHECK-NEXT: frame #3: 0x{{[0-9a-f]+}} a.out`func1() at main.cpp:25:3
10   // CHECK-SAME: [artificial]
11   // CHECK-NEXT: frame #4: 0x{{[0-9a-f]+}} a.out`main
12 }
13 
14 void __attribute__((noinline)) func3() {
15   x++;
16   sink(); /* tail */
17 }
18 
19 void __attribute__((disable_tail_calls, noinline)) func2() {
20   func3(); /* regular */
21 }
22 
23 void __attribute__((noinline)) func1() {
24   x++;
25   func2(); /* tail */
26 }
27 
28 int __attribute__((disable_tail_calls)) main() {
29   // DEBUG: self.runCmd("log enable lldb step -f /tmp/lldbstep.log")
30   func1(); /* regular */
31   return 0;
32 }
33