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/*

 * inspired by glibc-2.0.6/sysdeps/libm-ieee754/s_nextafterf.c

 *

 * gcc -O2 -S -DOP=+ gives faddp %st(1),%st

 * gcc -O2 -S -DOP=* gives fmulp %st(1),%st

 * gcc -O2 -S -DOP=- gives fsubrp %st(1),%st

 * gcc -O2 -S -DOP=/ gives fdivrp %st(1),%st

 */

#ifndef OP

#define OP *

#endif

typedef int int32_t __attribute__ ((__mode__ (  __SI__ ))) ;

typedef unsigned int u_int32_t __attribute__ ((__mode__ (  __SI__ ))) ;

typedef union

{

  float value;

  u_int32_t word;

} ieee_float_shape_type;

float __nextafterf(float x, float y)

{

 int32_t hx,hy,ix,iy;

 {

  ieee_float_shape_type gf_u;

  gf_u.value = x;

  hx = gf_u.word;

 }

 {

  ieee_float_shape_type gf_u;

  gf_u.value = y;

  hy = gf_u.word;

 }

 ix = hx&0x7fffffff;

 iy = hy&0x7fffffff;

 if ( ix > 0x7f800000 || iy > 0x7f800000 )

    return x+y;

 if (x == y) return x;

 if (ix == 0)

   {

    {

     ieee_float_shape_type sf_u;

     sf_u.word = (hy&0x80000000) | 1;

     x = sf_u.value;

    }

    y = x*x;

    if (y == x) return y; else return x;

   }

 if (hx >= 0)

   {

    if (hx > hy)

       hx -= 1;

    else

       hx += 1;

   }

 else

   {

    if (hy >= 0 || hx > hy)

       hx -= 1;

    else

       hx += 1;

   }

 hy = hx & 0x7f800000;

 if (hy >= 0x7f800000)

    return x+x;

 if (hy < 0x00800000)

   {

    y = x OP x;

    if (y != x)

      {

       ieee_float_shape_type sf_u;

       sf_u.word = hx;

       y = sf_u.value;

       return y;

      }

   }

 {

  ieee_float_shape_type sf_u;

  sf_u.word = hx;

  x = sf_u.value;

 }

 return x;

}