#include "emu.h"
#include "const.h"
#include "rmov.h"

extern "C" void shld(void *v);
extern "C" void shrd(void *v);

void normalize(reg& r)
{
  if (!(r.sigl | r.sigh))
  {
    r.exp = 0;
    r.tag = TW_Z;
    return;
  }
  if (r.exp >= EXP_MAX)
  {
    r.tag = TW_S;
    return;
  }
  while (!(r.sigh & 0x80000000))
  {
    if (r.exp == 0)
      return;
    shld(&r.sigl);
    r.exp--;
  }
}

void r_mov(long double *s, reg& d)
{
  unsigned long *sp = (unsigned long *)s;
  if (sp[2] & 0x8000)
    d.sign = SIGN_NEG;
  else
    d.sign = SIGN_POS;
  d.exp = sp[2] & 0x7fff;
  d.sigh = sp[1];
  d.sigl = sp[0];
  d.tag = TW_V;
  normalize(d);
}

void r_mov(double *s, reg& d)
{
  unsigned m64 = ((unsigned *)s)[1];
  unsigned l64 = ((unsigned *)s)[0];
  if (m64 & 0x80000000)
    d.sign = SIGN_NEG;
  else
    d.sign = SIGN_POS;
  if (!((m64 & 0x7fffffff) | (l64)))
  {
    int c = d.sign;
    r_mov(CONST_Z, d);
    d.sign = c;
    return;
  }
  d.exp = (int)((m64>>20)&0x7ff) - 1023 + EXP_BIAS;
  d.sigh = ((m64 & 0xfffff)<<11) | 0x80000000;
  d.sigh |= l64 >> 21;
  d.sigl = l64 << 11;
  d.tag = TW_V;
  if ((m64 & 0x7ff00000) == 0x7ff00000)
    d.exp = EXP_MAX;
  normalize(d);
}

void r_mov(float *s, reg& d)
{
  unsigned m32 = *(unsigned *)s;
  if (m32 & 0x80000000)
    d.sign = SIGN_NEG;
  else
    d.sign = SIGN_POS;
  if (!(m32 & 0x7fffffff))
  {
    int c = d.sign;
    r_mov(CONST_Z, d);
    d.sign = c;
    return;
  }
  d.exp = (int)((m32>>23)&0xff) - 127 + EXP_BIAS;
  d.sigh = ((m32 & 0x7fffff)<<8) | 0x80000000;
  d.sigl = 0;
  d.tag = TW_V;
  if ((m32 & 0x7f800000) == 0x7f800000)
    d.exp = EXP_MAX;
  normalize(d);
}

void r_mov(long long *_s, reg& d)
{
  long long s = *_s;
  if (s == 0)
    return r_mov(CONST_Z, d);

  if (s > 0)
    d.sign = SIGN_POS;
  else
  {
    s = -s;
    d.sign = SIGN_NEG;
  }

  int e = EXP_BIAS + 63;
  while (s >= 0)
  {
    shld(&s);
    e -= 1;
  }
  d.sigh = s >> 32;
  d.sigl = s;
  d.exp = e;
  d.tag = TW_V;
  normalize(d);
}

void r_mov(long *_s, reg& d)
{
  long s = *_s;
  if (s == 0)
    return r_mov(CONST_Z, d);

  if (s > 0)
    d.sign = SIGN_POS;
  else
  {
    s = -s;
    d.sign = SIGN_NEG;
  }

  int e = EXP_BIAS + 31;
  while (!(s & 0x80000000))
  {
    s <<= 1;
    e -= 1;
  }
  d.sigh = s;
  d.sigl = 0;
  d.exp = e;
  d.tag = TW_V;
  normalize(d);
}

void r_mov(short *_s, reg& d)
{
  int s = *_s;
  if (s == 0)
    return r_mov(CONST_Z, d);

  if (s > 0)
    d.sign = SIGN_POS;
  else
  {
    s = -s;
    d.sign = SIGN_NEG;
  }

  int e = EXP_BIAS + 15;
  while (!(s & 0x8000))
  {
    s <<= 1;
    e -= 1;
  }
  d.sigh = s << 16;
  d.sigl = 0;
  d.exp = e;
  d.tag = TW_V;
  normalize(d);
}

void r_mov(char *s, reg& d)
{
  int side=1, pos=8;
  long long l;
  l = 0;
  for (int i=0; i<18; i++)
  {
    l *= 10;
    switch (side)
    {
      case 0:
        l += s[pos] & 0x0f;
        side = 1;
        pos--;
        break;
      case 1:
        l += s[pos] >> 4;
        side = 0;
        break;
    }
  }
  r_mov(&l, d);
  if (s[9] & 0x80)
    d.sign = SIGN_NEG;
}

//=============================================================================

static void round_to_int(reg& r) // r gets mangled such that sig is int, sign
{
  reg t;
  int more_than_half = 0;
  int half_or_more = 0;
  if (r.tag == TW_Z)
  {
    return;
  }
  while (r.exp < EXP_BIAS+62)
  {
    if (r.sigl & 1)
      more_than_half = 1;
    shrd(&r.sigl);
    r.exp++;
  }
  while (r.exp < EXP_BIAS+63)
  {
    if (r.sigl & 1)
      half_or_more = 1;
    shrd(&r.sigl);
    r.exp++;
  }
  if (r.exp > EXP_BIAS+63)
  {
    r.sigl = r.sigh = ~0;
    return;
  }
  switch (control_word & CW_RC)
  {
    case RC_RND:
      if (half_or_more)
        if (more_than_half) // nearest
          (*(long long *)(&r.sigl)) ++;
        else
          if (r.sigl & 1) // odd?
            (*(long long *)(&r.sigl)) ++;
      break;
    case RC_DOWN:
      if ((half_or_more||more_than_half) && r.sign)
        (*(long long *)(&r.sigl)) ++;
      break;
    case RC_UP:
      if ((half_or_more||more_than_half) && !r.sign)
        (*(long long *)(&r.sigl)) ++;
      break;
    case RC_CHOP:
      break;
  }
}

void r_mov(reg& s, long double *d)
{
  ((short *)d)[2] = s.exp + s.sign*0x8000;
  ((long *)d)[0] = s.sigl;
  ((long *)d)[1] = s.sigh;
}

void r_mov(reg& s, double *d)
{
  unsigned long *l = (unsigned long *)d;
  if (s.tag == TW_Z)
  {
    l[0] = 0;
    l[1] = 0;
  }
  else
  {
    l[0] = (s.sigl >> 11) | (s.sigh << 21);
    l[1] = ((s.sigh >> 11) & 0xfffff) | (((s.exp-EXP_BIAS+1023) & 0x7ff) << 20);
  }
  if (s.sign)
    l[1] |= 0x80000000;
}

void r_mov(reg& s, float *d)
{
  long f;
  if (s.tag == TW_Z)
  {
    f = 0;
  }
  else
  {
    f = (s.sigh >> 8) & 0x007fffff;
    f |= ((s.exp-EXP_BIAS+127) & 0xff) << 23;
  }
  if (s.sign)
    f |= 0x80000000;
  *(long *)d = f;
}

void r_mov(reg& s, long long *d)
{
  reg t;
  r_mov(s, t);
  round_to_int(t);
  ((long *)d)[0] = t.sigl;
  ((long *)d)[1] = t.sigh;
  if (t.sign)
    *d = - *d;
}

void r_mov(reg& s, long *d)
{
  reg t;
  r_mov(s, t);
  round_to_int(t);
  if (t.sigh || (t.sigl & 0x80000000))
    *d = -1;
  else
    *d = s.sign ? -t.sigl : t.sigl;
}

void r_mov(reg& s, short *d)
{
  reg t;
  r_mov(s, t);
  round_to_int(t);
  if (t.sigh || (t.sigl & 0xFFFF8000))
    *d = -1;
  else
    *d = s.sign ? -t.sigl : t.sigl;
}

void r_mov(reg& s, char *d)
{
  reg t;
  r_mov(s, t);
  round_to_int(t);
  long long ll = *(long long *)(&t.sigl);
  int side = 0;
  int r, i;
  for (i=0; i<10; i++)
    d[i] = 0;
  int pos=0;
  for (i=0; i<18; i++)
  {
    r = ll % 10;
    ll /= 10;
    if (side)
    {
      d[pos] |= r << 4;
      side = 0;
      pos++;
    }
    else
    {
      d[pos] |= r;
      side = 1;
    }
  }
  if (s.sign == SIGN_NEG)
    d[9] = 0x80;
}