| void __attribute__((naked)) incomplete_cas(int *a, int *b) { |
| // Stop at the first instruction (an sc without a corresponding lr), then make |
| // a step instruction and ensure that execution stops at the next instruction |
| // (and a5, a2, a4). |
| asm volatile("1:\n\t" |
| "sc.w a5, a1, (a3)\n\t" |
| "and a5, a2, a4\n\t" |
| "beq a5, a1, 2f\n\t" |
| "xor a5, a2, a0\n\t" |
| "and a5, a5, a4\n\t" |
| "xor a5, a2, a5\n\t" |
| "sc.w a5, a1, (a3)\n\t" |
| "bnez a5, 1b\n\t" |
| "2:\n\t" |
| "ret\n\t"); |
| } |
| |
| int main() { |
| int a = 4; |
| int b = 2; |
| incomplete_cas(&a, &b); |
| } |