sc_unsigned.cpp

来自「基于4个mips核的noc设计」· C++ 代码 · 共 1,853 行 · 第 1/3 页

// Cases to consider when computing u + v:
// 1. u - 0 = u 
// 2. 0 - v = -v
// 3. if sgn(u) != sgn(v)
//    3.1 u - (-v) = u + v = sgn(u) * (u + v)
//    3.2 (-u) - v = -(u + v) ==> sgn(u) * (u + v)
// 4. if sgn(u) == sgn(v)
//    4.1 u - v = +(u - v) = sgn(u) * (u - v) 
//    4.2 (-u) - (-v) = -(u - v) = sgn(u) * (u - v)
//
// Specialization of above cases for computing --u or u--: 
// 1. 0 - 1 = -1
// 3. (-u) - 1 = -(u + 1) = sgn(u) * (u + 1)
// 4. u - 1 = u - 1 = sgn(u) * (u - 1)

// The operators in this section are included from sc_nbcommon.cpp.


// ----------------------------------------------------------------------------
//  SECTION: MULTIPLICATION operators: *, *=
// ----------------------------------------------------------------------------

// Cases to consider when computing u * v:
// 1. u * 0 = 0 * v = 0
// 2. 1 * v = v and -1 * v = -v
// 3. u * 1 = u and u * -1 = -u
// 4. u * v = u * v

sc_unsigned
operator*(const sc_unsigned& u, const sc_unsigned& v)
{
 
  small_type s = mul_signs(u.sgn, v.sgn);

  if (s == SC_ZERO) // case 1
    return sc_unsigned();

  // cases 2-4
  return mul_unsigned_friend(s, u.nbits, u.ndigits, u.digit,
                             v.nbits, v.ndigits, v.digit);

}


sc_unsigned
operator*(const sc_unsigned& u, uint64 v)
{

  small_type s = mul_signs(u.sgn, get_sign(v));

  if (s == SC_ZERO) // case 1
    return sc_unsigned();

  CONVERT_INT64_2(v);

  // cases 2-4
  return mul_unsigned_friend(s, u.nbits, u.ndigits, u.digit, 
                             BITS_PER_UINT64, DIGITS_PER_UINT64, vd);
  
}


sc_unsigned
operator*(uint64 u, const sc_unsigned& v)
{

  small_type s = mul_signs(v.sgn, get_sign(u));

  if (s == SC_ZERO) // case 1
    return sc_unsigned();

  CONVERT_INT64_2(u);

  // cases 2-4
  return mul_unsigned_friend(s, BITS_PER_UINT64, DIGITS_PER_UINT64, ud, 
                             v.nbits, v.ndigits, v.digit);
  
}


sc_unsigned
operator*(const sc_unsigned& u, unsigned long v)
{

  small_type s = mul_signs(u.sgn, get_sign(v));

  if (s == SC_ZERO) // case 1
    return sc_unsigned();

  CONVERT_LONG_2(v);

  // else cases 2-4
  return mul_unsigned_friend(s, u.nbits, u.ndigits, u.digit, 
                             BITS_PER_ULONG, DIGITS_PER_ULONG, vd);
  
}

sc_unsigned
operator*(unsigned long u, const sc_unsigned& v)
{

  small_type s = mul_signs(v.sgn, get_sign(u));

  if (s == SC_ZERO) // case 1
    return sc_unsigned();

  CONVERT_LONG_2(u);

  // cases 2-4
  return mul_unsigned_friend(s, BITS_PER_ULONG, DIGITS_PER_ULONG, ud, 
                             v.nbits, v.ndigits, v.digit);
  
}

// The rest of the operators in this section are included from
// sc_nbcommon.cpp.


// ----------------------------------------------------------------------------
//  SECTION: DIVISION operators: /, /=
// ----------------------------------------------------------------------------

// Cases to consider when finding the quotient q = floor(u/v):
// Note that u = q * v + r for r < q.
// 1. 0 / 0 or u / 0 => error
// 2. 0 / v => 0 = 0 * v + 0
// 3. u / v && u = v => u = 1 * u + 0  - u or v can be 1 or -1
// 4. u / v && u < v => u = 0 * v + u  - u can be 1 or -1
// 5. u / v && u > v => u = q * v + r  - v can be 1 or -1

sc_unsigned
operator/(const sc_unsigned& u, const sc_unsigned& v)
{

  small_type s = mul_signs(u.sgn, v.sgn);

  if (s == SC_ZERO) {
    div_by_zero(v.sgn); // case 1
    return sc_unsigned();  // case 2
  }

  // other cases
  return div_unsigned_friend(s, u.nbits, u.ndigits, u.digit,
                             v.nbits, v.ndigits, v.digit);

}


sc_unsigned
operator/(const sc_unsigned& u, uint64 v)
{

  small_type s = mul_signs(u.sgn, get_sign(v));

  if (s == SC_ZERO) {
    div_by_zero(v);  // case 1
    return sc_unsigned();  // case 2
  }

  CONVERT_INT64_2(v);

  // other cases
  return div_unsigned_friend(s, u.nbits, u.ndigits, u.digit, 
                             BITS_PER_UINT64, DIGITS_PER_UINT64, vd);
  
}


sc_unsigned
operator/(uint64 u, const sc_unsigned& v)
{

  small_type s = mul_signs(v.sgn, get_sign(u));

  if (s == SC_ZERO) {
    div_by_zero(v.sgn);  // case 1
    return sc_unsigned();  // case 2

  }

  CONVERT_INT64_2(u);

  // other cases
  return div_unsigned_friend(s, BITS_PER_UINT64, DIGITS_PER_UINT64, ud, 
                             v.nbits, v.ndigits, v.digit);
  
}


sc_unsigned
operator/(const sc_unsigned& u, unsigned long v)
{

  small_type s = mul_signs(u.sgn, get_sign(v));

  if (s == SC_ZERO) {
    div_by_zero(v);  // case 1
    return sc_unsigned();  // case 2
  }

  CONVERT_LONG_2(v);

  // other cases
  return div_unsigned_friend(s, u.nbits, u.ndigits, u.digit, 
                             BITS_PER_ULONG, DIGITS_PER_ULONG, vd);
  
}


sc_unsigned
operator/(unsigned long u, const sc_unsigned& v)
{

  small_type s = mul_signs(v.sgn, get_sign(u));

  if (s == SC_ZERO) {
    div_by_zero(v.sgn);  // case 1
    return sc_unsigned();  // case 2

  }

  CONVERT_LONG_2(u);

  // other cases
  return div_unsigned_friend(s, BITS_PER_ULONG, DIGITS_PER_ULONG, ud, 
                             v.nbits, v.ndigits, v.digit);
  
}

// The rest of the operators in this section are included from
// sc_nbcommon.cpp.


// ----------------------------------------------------------------------------
//  SECTION: MOD operators: %, %=.
// ----------------------------------------------------------------------------

// Cases to consider when finding the remainder r = u % v:
// Note that u = q * v + r for r < q.
// 1. 0 % 0 or u % 0 => error
// 2. 0 % v => 0 = 0 * v + 0
// 3. u % v && u = v => u = 1 * u + 0  - u or v can be 1 or -1
// 4. u % v && u < v => u = 0 * v + u  - u can be 1 or -1
// 5. u % v && u > v => u = q * v + r  - v can be 1 or -1

sc_unsigned
operator%(const sc_unsigned& u, const sc_unsigned& v)
{

  if ((u.sgn == SC_ZERO) || (v.sgn == SC_ZERO)) {
    div_by_zero(v.sgn);  // case 1
    return sc_unsigned();  // case 2
  }

  // other cases
  return mod_unsigned_friend(u.sgn, u.nbits, u.ndigits, u.digit,
                             v.nbits, v.ndigits, v.digit);
}


sc_unsigned
operator%(const sc_unsigned& u, uint64 v)
{

  if ((u.sgn == SC_ZERO) || (v == 0)) {
    div_by_zero(v);  // case 1
    return sc_unsigned();  // case 2
  }

  CONVERT_INT64_2(v);

  // other cases
  return mod_unsigned_friend(u.sgn, u.nbits, u.ndigits, u.digit,
                             BITS_PER_UINT64, DIGITS_PER_UINT64, vd);

}


sc_unsigned
operator%(uint64 u, const sc_unsigned& v)
{

  if ((u == 0) || (v.sgn == SC_ZERO)) {
    div_by_zero(v.sgn);  // case 1
    return sc_unsigned();  // case 2
  }

  CONVERT_INT64(u);

  // other cases
  return mod_unsigned_friend(us, BITS_PER_UINT64, DIGITS_PER_UINT64, ud,
                             v.nbits, v.ndigits, v.digit);

}


sc_unsigned
operator%(const sc_unsigned& u, unsigned long v)
{

  if ((u.sgn == SC_ZERO) || (v == 0)) {
    div_by_zero(v);  // case 1
    return sc_unsigned();  // case 2
  }

  CONVERT_LONG_2(v);

  // other cases
  return mod_unsigned_friend(u.sgn, u.nbits, u.ndigits, u.digit,
                             BITS_PER_ULONG, DIGITS_PER_ULONG, vd);

}


sc_unsigned
operator%(unsigned long u, const sc_unsigned& v)
{

  if ((u == 0) || (v.sgn == SC_ZERO)) {
    div_by_zero(v.sgn);  // case 1
    return sc_unsigned();  // case 2
  }

  CONVERT_LONG(u);

  // other cases
  return mod_unsigned_friend(us, BITS_PER_ULONG, DIGITS_PER_ULONG, ud,
                             v.nbits, v.ndigits, v.digit);

}

// The rest of the operators in this section are included from
// sc_nbcommon.cpp.


// ----------------------------------------------------------------------------
//  SECTION: Bitwise AND operators: &, &=
// ----------------------------------------------------------------------------

// Cases to consider when computing u & v:
// 1. u & 0 = 0 & v = 0
// 2. u & v => sgn = +
// 3. (-u) & (-v) => sgn = -
// 4. u & (-v) => sgn = +
// 5. (-u) & v => sgn = +

sc_unsigned
operator&(const sc_unsigned& u, const sc_unsigned& v)
{

  if ((u.sgn == SC_ZERO) || (v.sgn == SC_ZERO)) // case 1
    return sc_unsigned();

  // other cases
  return and_unsigned_friend(u.sgn, u.nbits, u.ndigits, u.digit,
                             v.sgn, v.nbits, v.ndigits, v.digit);

}


sc_unsigned
operator&(const sc_unsigned& u, uint64 v)
{

  if ((u.sgn == SC_ZERO) || (v == 0)) // case 1
    return sc_unsigned();

  CONVERT_INT64(v);

  // other cases
  return and_unsigned_friend(u.sgn, u.nbits, u.ndigits, u.digit,
                             vs, BITS_PER_UINT64, DIGITS_PER_UINT64, vd);
  
}


sc_unsigned
operator&(uint64 u, const sc_unsigned& v)
{

  if ((u == 0) || (v.sgn == SC_ZERO)) // case 1
    return sc_unsigned();

  CONVERT_INT64(u);

  // other cases
  return and_unsigned_friend(us, BITS_PER_UINT64, DIGITS_PER_UINT64, ud,
                             v.sgn, v.nbits, v.ndigits, v.digit);

}


sc_unsigned
operator&(const sc_unsigned& u, unsigned long v)
{

  if ((u.sgn == SC_ZERO) || (v == 0)) // case 1
    return sc_unsigned();

  CONVERT_LONG(v);

  // other cases
  return and_unsigned_friend(u.sgn, u.nbits, u.ndigits, u.digit,
                             vs, BITS_PER_ULONG, DIGITS_PER_ULONG, vd);

}


sc_unsigned
operator&(unsigned long u, const sc_unsigned& v)
{

  if ((u == 0) || (v.sgn == SC_ZERO)) // case 1
    return sc_unsigned();

  CONVERT_LONG(u);

  // other cases
  return and_unsigned_friend(us, BITS_PER_ULONG, DIGITS_PER_ULONG, ud,
                             v.sgn, v.nbits, v.ndigits, v.digit);

}

// The rest of the operators in this section are included from
// sc_nbcommon.cpp.


// ----------------------------------------------------------------------------
//  SECTION: Bitwise OR operators: |, |=
// ----------------------------------------------------------------------------

// Cases to consider when computing u | v:
// 1. u | 0 = u
// 2. 0 | v = v
// 3. u | v => sgn = +
// 4. (-u) | (-v) => sgn = -
// 5. u | (-v) => sgn = -
// 6. (-u) | v => sgn = -

sc_unsigned
operator|(const sc_unsigned& u, const sc_unsigned& v)
{

  if (v.sgn == SC_ZERO)  // case 1
    return sc_unsigned(u);

  if (u.sgn == SC_ZERO)  // case 2
    return sc_unsigned(v);

  // other cases
  return or_unsigned_friend(u.sgn, u.nbits, u.ndigits, u.digit,
                            v.sgn, v.nbits, v.ndigits, v.digit);

}


sc_unsigned
operator|(const sc_unsigned& u, uint64 v)
{

  if (v == 0)  // case 1
    return sc_unsigned(u);

  CONVERT_INT64(v);

  if (u.sgn == SC_ZERO)  // case 2
    return sc_unsigned(vs, BITS_PER_UINT64, DIGITS_PER_UINT64, vd, false);

  // other cases
  return or_unsigned_friend(u.sgn, u.nbits, u.ndigits, u.digit,
                            vs, BITS_PER_UINT64, DIGITS_PER_UINT64, vd);

}


sc_unsigned
operator|(uint64 u, const sc_unsigned& v)
{

  if (u == 0)
    return sc_unsigned(v);

  CONVERT_INT64(u);

  if (v.sgn == SC_ZERO)
    return sc_unsigned(us, BITS_PER_UINT64, DIGITS_PER_UINT64, ud, false);

  // other cases
  return or_unsigned_friend(us, BITS_PER_UINT64, DIGITS_PER_UINT64, ud,
                            v.sgn, v.nbits, v.ndigits, v.digit);

}


sc_unsigned
operator|(const sc_unsigned& u, unsigned long v)
{

  if (v == 0)  // case 1
    return sc_unsigned(u);

  CONVERT_LONG(v);

  if (u.sgn == SC_ZERO)  // case 2
    return sc_unsigned(vs, BITS_PER_ULONG, DIGITS_PER_ULONG, vd, false);

  // other cases
  return or_unsigned_friend(u.sgn, u.nbits, u.ndigits, u.digit,
                            vs, BITS_PER_ULONG, DIGITS_PER_ULONG, vd);

}


sc_unsigned
operator|(unsigned long u, const sc_unsigned& v)
{

  if (u == 0)
    return sc_unsigned(v);

  CONVERT_LONG(u);

  if (v.sgn == SC_ZERO)
    return sc_unsigned(us, BITS_PER_ULONG, DIGITS_PER_ULONG, ud, false);

  // other cases
  return or_unsigned_friend(us, BITS_PER_ULONG, DIGITS_PER_ULONG, ud,
                            v.sgn, v.nbits, v.ndigits, v.digit);

}

// The rest of the operators in this section are included from
// sc_nbcommon.cpp.


// ----------------------------------------------------------------------------
//  SECTION: Bitwise XOR operators: ^, ^=
// ----------------------------------------------------------------------------

// Cases to consider when computing u ^ v:
// Note that  u ^ v = (~u & v) | (u & ~v).
// 1. u ^ 0 = u
// 2. 0 ^ v = v
// 3. u ^ v => sgn = +
// 4. (-u) ^ (-v) => sgn = -
// 5. u ^ (-v) => sgn = -
// 6. (-u) ^ v => sgn = +

sc_unsigned
operator^(const sc_unsigned& u, const sc_unsigned& v)
{

  if (v.sgn == SC_ZERO)  // case 1
    return sc_unsigned(u);

  if (u.sgn == SC_ZERO)  // case 2
    return sc_unsigned(v);

  // other cases
  return xor_unsigned_friend(u.sgn, u.nbits, u.ndigits, u.digit,
                             v.sgn, v.nbits, v.ndigits, v.digit);

}


sc_unsigned
operator^(const sc_unsigned& u, uint64 v)
{

  if (v == 0)  // case 1
    return sc_unsigned(u);

  CONVERT_INT64(v);

  if (u.sgn == SC_ZERO)  // case 2
    return sc_unsigned(vs, BITS_PER_UINT64, DIGITS_PER_UINT64, vd, false);

  // other cases
  return xor_unsigned_friend(u.sgn, u.nbits, u.ndigits, u.digit,
                             vs, BITS_PER_UINT64, DIGITS_PER_UINT64, vd);

}

sc_unsigned
operator^(uint64 u, const sc_unsigned& v)
{
  if (u == 0)
    return sc_unsigned(v);

  CONVERT_INT64(u);

  if (v.sgn == SC_ZERO)
    return sc_unsigned(us, BITS_PER_UINT64, DIGITS_PER_UINT64, ud, false);

  // other cases
  return xor_unsigned_friend(us, BITS_PER_UINT64, DIGITS_PER_UINT64, ud,
                             v.sgn, v.nbits, v.ndigits, v.digit);

}


sc_unsigned
operator^(const sc_unsigned& u, unsigned long v)
{

  if (v == 0)  // case 1
    return sc_unsigned(u);

  CONVERT_LONG(v);

  if (u.sgn == SC_ZERO)  // case 2
    return sc_unsigned(vs, BITS_PER_ULONG, DIGITS_PER_ULONG, vd, false);

  // other cases
  return xor_unsigned_friend(u.sgn, u.nbits, u.ndigits, u.digit,
                             vs, BITS_PER_ULONG, DIGITS_PER_ULONG, vd);

}