int __kprobes disasm_next_pc()

in kernel/disasm.c [500:533]

• 21 lines of code
• 6 McCabe index (conditional complexity)

int __kprobes disasm_next_pc(unsigned long pc, struct pt_regs *regs,
			     struct callee_regs *cregs,
			     unsigned long *next_pc, unsigned long *tgt_if_br)
{
	struct disasm_state instr;

	memset(&instr, 0, sizeof(struct disasm_state));
	disasm_instr(pc, &instr, 0, regs, cregs);

	*next_pc = pc + instr.instr_len;

	/* Instruction with possible two targets branch, jump and loop */
	if (instr.is_branch)
		*tgt_if_br = instr.target;

	/* For the instructions with delay slots, the fall through is the
	 * instruction following the instruction in delay slot.
	 */
	 if (instr.delay_slot) {
		struct disasm_state instr_d;

		disasm_instr(*next_pc, &instr_d, 0, regs, cregs);

		*next_pc += instr_d.instr_len;
	 }

	 /* Zero Overhead Loop - end of the loop */
	if (!(regs->status32 & STATUS32_L) && (*next_pc == regs->lp_end)
		&& (regs->lp_count > 1)) {
		*next_pc = regs->lp_start;
	}

	return instr.is_branch;
}