Example #1
0
CFLOAT
M_DECL_FUNC (__csin) (CFLOAT x)
{
  CFLOAT retval;
  int negate = signbit (__real__ x);
  int rcls = fpclassify (__real__ x);
  int icls = fpclassify (__imag__ x);

  __real__ x = M_FABS (__real__ x);

  if (__glibc_likely (icls >= FP_ZERO))
    {
      /* Imaginary part is finite.  */
      if (__glibc_likely (rcls >= FP_ZERO))
	{
	  /* Real part is finite.  */
	  const int t = (int) ((M_MAX_EXP - 1) * M_MLIT (M_LN2));
	  FLOAT sinix, cosix;

	  if (__glibc_likely (__real__ x > M_MIN))
	    {
	      M_SINCOS (__real__ x, &sinix, &cosix);
	    }
	  else
	    {
	      sinix = __real__ x;
	      cosix = 1;
	    }

	  if (negate)
	    sinix = -sinix;

	  if (M_FABS (__imag__ x) > t)
	    {
	      FLOAT exp_t = M_EXP (t);
	      FLOAT ix = M_FABS (__imag__ x);
	      if (signbit (__imag__ x))
		cosix = -cosix;
	      ix -= t;
	      sinix *= exp_t / 2;
	      cosix *= exp_t / 2;
	      if (ix > t)
		{
		  ix -= t;
		  sinix *= exp_t;
		  cosix *= exp_t;
		}
	      if (ix > t)
		{
		  /* Overflow (original imaginary part of x > 3t).  */
		  __real__ retval = M_MAX * sinix;
		  __imag__ retval = M_MAX * cosix;
		}
	      else
		{
		  FLOAT exp_val = M_EXP (ix);
		  __real__ retval = exp_val * sinix;
		  __imag__ retval = exp_val * cosix;
		}
	    }
	  else
	    {
	      __real__ retval = M_COSH (__imag__ x) * sinix;
	      __imag__ retval = M_SINH (__imag__ x) * cosix;
	    }

	  math_check_force_underflow_complex (retval);
	}
      else
	{
	  if (icls == FP_ZERO)
	    {
	      /* Imaginary part is 0.0.  */
	      __real__ retval = __real__ x - __real__ x;
	      __imag__ retval = __imag__ x;
	    }
	  else
	    {
	      __real__ retval = M_NAN;
	      __imag__ retval = M_NAN;

	      feraiseexcept (FE_INVALID);
	    }
	}
    }
  else if (icls == FP_INFINITE)
    {
      /* Imaginary part is infinite.  */
      if (rcls == FP_ZERO)
	{
	  /* Real part is 0.0.  */
	  __real__ retval = M_COPYSIGN (0, negate ? -1 : 1);
	  __imag__ retval = __imag__ x;
	}
      else if (rcls > FP_ZERO)
	{
	  /* Real part is finite.  */
	  FLOAT sinix, cosix;

	  if (__glibc_likely (__real__ x > M_MIN))
	    {
	      M_SINCOS (__real__ x, &sinix, &cosix);
	    }
	  else
	    {
	      sinix = __real__ x;
	      cosix = 1;
	    }

	  __real__ retval = M_COPYSIGN (M_HUGE_VAL, sinix);
	  __imag__ retval = M_COPYSIGN (M_HUGE_VAL, cosix);

	  if (negate)
	    __real__ retval = -__real__ retval;
	  if (signbit (__imag__ x))
	    __imag__ retval = -__imag__ retval;
	}
      else
	{
	  __real__ retval = __real__ x - __real__ x;
	  __imag__ retval = M_HUGE_VAL;
	}
    }
  else
    {
      if (rcls == FP_ZERO)
	__real__ retval = M_COPYSIGN (0, negate ? -1 : 1);
      else
	__real__ retval = M_NAN;
      __imag__ retval = M_NAN;
    }

  return retval;
}
Example #2
0
CFLOAT
M_DECL_FUNC (__ctanh) (CFLOAT x)
{
  CFLOAT res;

  if (__glibc_unlikely (!isfinite (__real__ x) || !isfinite (__imag__ x)))
    {
      if (isinf (__real__ x))
	{
	  __real__ res = M_COPYSIGN (1, __real__ x);
	  if (isfinite (__imag__ x) && M_FABS (__imag__ x) > 1)
	    {
	      FLOAT sinix, cosix;
	      M_SINCOS (__imag__ x, &sinix, &cosix);
	      __imag__ res = M_COPYSIGN (0, sinix * cosix);
	    }
	  else
	    __imag__ res = M_COPYSIGN (0, __imag__ x);
	}
      else if (__imag__ x == 0)
	{
	  res = x;
	}
      else
	{
	  __real__ res = M_NAN;
	  __imag__ res = M_NAN;

	  if (isinf (__imag__ x))
	    feraiseexcept (FE_INVALID);
	}
    }
  else
    {
      FLOAT sinix, cosix;
      FLOAT den;
      const int t = (int) ((M_MAX_EXP - 1) * M_MLIT (M_LN2) / 2);

      /* tanh(x+iy) = (sinh(2x) + i*sin(2y))/(cosh(2x) + cos(2y))
	 = (sinh(x)*cosh(x) + i*sin(y)*cos(y))/(sinh(x)^2 + cos(y)^2).  */

      if (__glibc_likely (M_FABS (__imag__ x) > M_MIN))
	{
	  M_SINCOS (__imag__ x, &sinix, &cosix);
	}
      else
	{
	  sinix = __imag__ x;
	  cosix = 1;
	}

      if (M_FABS (__real__ x) > t)
	{
	  /* Avoid intermediate overflow when the imaginary part of
	     the result may be subnormal.  Ignoring negligible terms,
	     the real part is +/- 1, the imaginary part is
	     sin(y)*cos(y)/sinh(x)^2 = 4*sin(y)*cos(y)/exp(2x).  */
	  FLOAT exp_2t = M_EXP (2 * t);

	  __real__ res = M_COPYSIGN (1, __real__ x);
	  __imag__ res = 4 * sinix * cosix;
	  __real__ x = M_FABS (__real__ x);
	  __real__ x -= t;
	  __imag__ res /= exp_2t;
	  if (__real__ x > t)
	    {
	      /* Underflow (original real part of x has absolute value
		 > 2t).  */
	      __imag__ res /= exp_2t;
	    }
	  else
	    __imag__ res /= M_EXP (2 * __real__ x);
	}
      else
	{
	  FLOAT sinhrx, coshrx;
	  if (M_FABS (__real__ x) > M_MIN)
	    {
	      sinhrx = M_SINH (__real__ x);
	      coshrx = M_COSH (__real__ x);
	    }
	  else
	    {
	      sinhrx = __real__ x;
	      coshrx = 1;
	    }

	  if (M_FABS (sinhrx) > M_FABS (cosix) * M_EPSILON)
	    den = sinhrx * sinhrx + cosix * cosix;
	  else
	    den = cosix * cosix;
	  __real__ res = sinhrx * coshrx / den;
	  __imag__ res = sinix * cosix / den;
	}
      math_check_force_underflow_complex (res);
    }

  return res;
}