1 #include <cinttypes>
2 #include <cstdint>
3 #include <cstdio>
4 
5 union alignas(16) xmm_t {
6   uint64_t as_uint64[2];
7   uint8_t as_uint8[16];
8 };
9 
10 int main() {
11   constexpr xmm_t xmm_fill = {
12     .as_uint64 = { 0, 0 }
13   };
14 
15   uint64_t mm[8];
16   xmm_t xmm[8];
17 
18   asm volatile(
19     "movq    %2, %%mm0\n\t"
20     "movq    %2, %%mm1\n\t"
21     "movq    %2, %%mm2\n\t"
22     "movq    %2, %%mm3\n\t"
23     "movq    %2, %%mm4\n\t"
24     "movq    %2, %%mm5\n\t"
25     "movq    %2, %%mm6\n\t"
26     "movq    %2, %%mm7\n\t"
27     "\n\t"
28     "movaps  %2, %%xmm0\n\t"
29     "movaps  %2, %%xmm1\n\t"
30     "movaps  %2, %%xmm2\n\t"
31     "movaps  %2, %%xmm3\n\t"
32     "movaps  %2, %%xmm4\n\t"
33     "movaps  %2, %%xmm5\n\t"
34     "movaps  %2, %%xmm6\n\t"
35     "movaps  %2, %%xmm7\n\t"
36     "\n\t"
37     "int3\n\t"
38     "\n\t"
39     "movq    %%mm0, 0x00(%0)\n\t"
40     "movq    %%mm1, 0x08(%0)\n\t"
41     "movq    %%mm2, 0x10(%0)\n\t"
42     "movq    %%mm3, 0x18(%0)\n\t"
43     "movq    %%mm4, 0x20(%0)\n\t"
44     "movq    %%mm5, 0x28(%0)\n\t"
45     "movq    %%mm6, 0x30(%0)\n\t"
46     "movq    %%mm7, 0x38(%0)\n\t"
47     "\n\t"
48     "movaps  %%xmm0, 0x00(%1)\n\t"
49     "movaps  %%xmm1, 0x10(%1)\n\t"
50     "movaps  %%xmm2, 0x20(%1)\n\t"
51     "movaps  %%xmm3, 0x30(%1)\n\t"
52     "movaps  %%xmm4, 0x40(%1)\n\t"
53     "movaps  %%xmm5, 0x50(%1)\n\t"
54     "movaps  %%xmm6, 0x60(%1)\n\t"
55     "movaps  %%xmm7, 0x70(%1)\n\t"
56     :
57     : "a"(mm), "b"(xmm), "m"(xmm_fill)
58     : "%mm0", "%mm1", "%mm2", "%mm3", "%mm4", "%mm5", "%mm6", "%mm7", "%xmm0",
59       "%xmm1", "%xmm2", "%xmm3", "%xmm4", "%xmm5", "%xmm6", "%xmm7"
60   );
61 
62   for (int i = 0; i < 8; ++i)
63     printf("mm%d = 0x%016" PRIx64 "\n", i, mm[i]);
64   for (int i = 0; i < 8; ++i) {
65     printf("xmm%d = { ", i);
66     for (int j = 0; j < sizeof(xmm->as_uint8); ++j)
67       printf("0x%02x ", xmm[i].as_uint8[j]);
68     printf("}\n");
69   }
70 
71   return 0;
72 }
73