struct _IO_APIC_REGISTERS {
volatile unsigned long RegisterIndex;/* 0x0 4 */
volatile unsigned long Reserved1[3];/* 0x4 12 */
volatile unsigned long RegisterValue;/* 0x10 4 */
volatile unsigned long Reserved2[11];/* 0x14 44 */
/* ── cacheline 1 boundary (64 bytes) ── */
volatile unsigned long EndOfInterrupt;/* 0x40 4 */
};