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1void __attribute__((naked)) branch_cas(int *a, int *b) {2 // Stop at the first instruction. The atomic sequence contains active forward3 // branch (bne a5, a1, 2f). After step instruction lldb should stop at the4 // branch's target address (ret instruction).5 asm volatile("1:\n\t"6 "lr.w a2, (a0)\n\t"7 "and a5, a2, a4\n\t"8 "bne a5, a1, 2f\n\t"9 "xor a5, a2, a0\n\t"10 "and a5, a5, a4\n\t"11 "xor a5, a2, a5\n\t"12 "sc.w a5, a1, (a3)\n\t"13 "beqz a5, 1b\n\t"14 "nop\n\t"15 "2:\n\t"16 "ret\n\t");17}18 19int main() {20 int a = 4;21 int b = 2;22 branch_cas(&a, &b);23}24