message: Do not use __vectorcall calling convention on WIN64 by default.
diff: #define ARRAY_SIZE 256
  #ifdef ISPC_IS_WINDOWS64
  -#define CALLINGCONV __vectorcall
  +// __vectorcall calling convention is off by default.
  +#define CALLINGCONV //__vectorcall
  #else
  #define CALLINGCONV
  #endif
  