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/* origin: FreeBSD /usr/src/lib/msun/src/s_nextafterf.c */
/*
* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
*/
/*
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
#include "libm.h"
float nextafterf(float x, float y)
{
volatile float t;
int32_t hx,hy,ix,iy;
GET_FLOAT_WORD(hx, x);
GET_FLOAT_WORD(hy, y);
ix = hx & 0x7fffffff; /* |x| */
iy = hy & 0x7fffffff; /* |y| */
if (ix > 0x7f800000 || /* x is nan */
iy > 0x7f800000) /* y is nan */
return x+y;
if (x == y) /* x == y */
return y;
if (ix == 0) { /* x == 0 */
SET_FLOAT_WORD(x, (hy&0x80000000)|1); /* return +-minsubnormal */
/* raise underflow flag */
t = x*x;
if (t == x)
return t;
return x;
}
if (hx >= 0) { /* x > 0 */
if (hx > hy) { /* x > y, x -= ulp */
hx--;
} else { /* x < y, x += ulp */
hx++;
}
} else { /* x < 0 */
if (hy >= 0 || hx > hy) { /* x < y, x -= ulp */
hx--;
} else { /* x > y, x += ulp */
hx++;
}
}
hy = hx & 0x7f800000;
if (hy >= 0x7f800000) /* overflow */
return x+x;
if (hy < 0x00800000) { /* underflow */
/* raise underflow flag */
t = x*x;
if (t != x) {
SET_FLOAT_WORD(y, hx);
return y;
}
}
SET_FLOAT_WORD(x, hx);
return x;
}
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