ec_arm_linux.c

来自「分别在x86」· C语言 代码 · 共 29 行

uint32 cq_ntohl(uint32 value)
{
	uint32 tmp;
	asm volatile ("EOR %1, %0, %0, ROR #16\n"
		"BIC %1, %1, #0xff0000\n"
		"MOV %0, %0, ROR #8\n"
		"EOR %0, %0, %1, LSR #8\n"
		: "=r" (value), "=r" (tmp)
		: "0" (value), "1" (tmp));
	return value;
}

void cq_ntohl_array(uint32* arr, uint32 num)
{
	uint32 tmp;
	uint32 value;
	asm volatile (""
		"next:\n"
		"ldr %2, [%0]\n"
		"EOR %3, %2, %2, ROR #16\n"
		"BIC %3, %3, #0xff0000\n"
		"MOV %2, %2, ROR #8\n"
		"EOR %2, %2, %3, LSR #8\n"
		"str %2, [%0], #4\n"
		"subs %1, %1, #1\n"
		"bne next\n"
		: "=r" (arr), "=r" (num), "=r" (value), "=r" (tmp)
		: "0" (arr), "1" (num), "2" (value), "3" (tmp));
}