movqu在ARM上的替换方法

指令功能Move unaligned double quadword.实现寄存器到寄存器，寄存器到地址的数据拷贝。

• x86上的指令用法：

  MOVDQU xmm1, xmm2/m128

• ARM上替换指令为：

  ldp指令：Load Pair Registers (extended): loads two doublewords from memory addressed by addr to Xt1 and Xt2.

  LDP Xt1, Xt2, addr

  stp指令：Store Pair Registers (extended): stores two doublewords from Xt1 and Xt2 to memory addressed by addr.

  STP Xt1, Xt2, addr