#include <stdio.h>
#include <mmintrin.h>

#define AS_QWORD "%16.16Lx"

__m64   a;
__m64   b = { 0x0123456789abcdef };
__m64   c = { 0xfedcba9876543210 };

void main()
  {
    a = _m_por( b, c );
    printf( "m1="AS_QWORD"\n"
            "m2="AS_QWORD"\n"
            "mm="AS_QWORD"\n",
            b, c, a );
  }