__asm вставка на x64

double to64(unsigned char *x)
{
    unsigned char c[10] = { 0 };
    ::memcpy(c, x, 10);
 
    double d = 0;
 
    __asm
    {
        fld   TBYTE PTR c
        fstp  d
    }
 
    return d;
}

 long double a=0.1;
 cout<<(double)(a);

#include <iostream>
 
extern "C" double convert10to8(const unsigned char *ld);
 
int main(void)
{
  unsigned char c[] = { 0xba, 0x4b, 0x55, 0x55, 0x55, 0x55, 0x55, 0xd5, 0xfc, 0x3f };
  double d = convert10to8(c);
  std::cout << d << std::endl;
}

#include <iostream>
 
unsigned char c[] = { 0xba, 0x4b, 0x55, 0x55, 0x55, 0x55, 0x55, 0xd5, 0xfc, 0x3f };
 
double to64(unsigned char *x)
{
    double d(*(double*)x);
    return d;
}
 
using namespace std;
 
int main()
{
    cout<<to64(c);
 
    return 0;
}

#include <iostream>
#include <cstring>
 
unsigned char c[] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x80, 0xfe, 0x3f };
 
double to64(const unsigned char x[10])
{
    int e = (((x[9] << 8) | x[8]) & 0x7FFF);
    uint64_t m =
        ((uint64_t)x[7] << 56) | ((uint64_t)x[6] << 48) | ((uint64_t)x[5] << 40) | ((uint64_t)x[4] << 32) | 
        ((uint64_t)x[3] << 24) | ((uint64_t)x[2] << 16) | ((uint64_t)x[1] << 8) | (uint64_t)x[0];
    unsigned char d[8] = {0};
    double result;
 
    d[7] = x[9] & 0x80;
 
    if ((e == 0x7FFF) || (e == 0))
    {
        if (e == 0x7FFF)
        {
            d[7] |= 0x7F;
            d[6] = 0xF0;
        }
        else
        {
            memcpy(&result, d, 8);
            return result;
        }
    }
    else
    {
        e = e - 0x3FFF + 0x03FF;
 
        if (e <= -52) 
        {
            memcpy(&result, d, 8);
            return result;
        }
        else if (e >= 0x7FF)
        {
            d[7] |= 0x7F;
            d[6] = 0xF0;
            memset(d, 0x00, 6);
            memcpy(&result, d, 8);
            return result;
        }
        else
        {
            d[7] |= (e & 0x7F0) >> 4;
            d[6] |= (e & 0xF) << 4;
        }
    }
 
    m >>= 11;
 
    if (e < 0) m>>=(-e + 1);
 
    d[0] = m & 0xFF;
    d[1] = (m >> 8) & 0xFF;
    d[2] = (m >> 16) & 0xFF;
    d[3] = (m >> 24) & 0xFF;
    d[4] = (m >> 32) & 0xFF;
    d[5] = (m >> 40) & 0xFF;
    d[6] |= (m >> 48) & 0x0F;
    memcpy(&result, d, 8);
 
    return result;
}
 
int main(void)
{
   std::cout<<to64(c);
}