Swizzles in Clang, GCC, and Visual c++

Swizzles.h

#include <stdio.h>

// #define CLANG_OR_GCC 
// Compile with -O3 -std=c++11 for Clang version

#define VS
// Compile with -O3 -fms-compatibility -std=c++11 for VS version

#if defined(CLANG_OR_GCC)
  typedef float float2 __attribute__((ext_vector_type(2)));
#elif defined(VS)
  struct float2
  {
    float x, y;
    // xy
    __declspec(property(get = get_xy, put = put_xy)) float2 xy;
    inline float2 get_xy() const { return {x, y}; }
    inline void put_xy(float2 v){ *this = v.xy; }
    // yx
    __declspec(property(get = get_yx, put = put_yx)) float2 yx;
    inline float2 get_yx() const { return {y, x}; }
    inline void put_yx(float2 v){ *this = v.yx; }
  };
#else
  #error
#endif

int main()
{

  float2 v1{1.0f, 2.0f};
  float2 v2 = v1.xy;

  printf("v = {x:%f, y:%f, }\n", v2.x, v2.y);
  v2.yx = v1.xy;
 
  printf("v = {x:%f, y:%f, }\n", v2.x, v2.y);
  
  return 0;
}


/*
GENERATED ASSEMBLY FOR BOTH VERSIONS IN CLANG 3.9.0 -O3

.LCPI0_0:
        .quad   4607182418800017408     # double 1
.LCPI0_1:
        .quad   4611686018427387904     # double 2
main:                                   # @main
        push    rax
        movsd   xmm0, qword ptr [rip + .LCPI0_0] # xmm0 = mem[0],zero
        movsd   xmm1, qword ptr [rip + .LCPI0_1] # xmm1 = mem[0],zero
        mov     edi, .L.str
        mov     al, 2
        call    printf
        mov     edi, .L.str
        mov     al, 2
        movsd   xmm0, qword ptr [rip + .LCPI0_1] # xmm0 = mem[0],zero
        movsd   xmm1, qword ptr [rip + .LCPI0_0] # xmm1 = mem[0],zero
        call    printf
        xor     eax, eax
        pop     rcx
        ret

.L.str:
        .asciz  "v = {x:%f, y:%f, }\n"

*/