2014-09-21 17:33:12 +00:00
|
|
|
/* nextafterq.c -- __float128 version of s_nextafter.c.
|
2012-03-27 23:13:14 +00:00
|
|
|
* Conversion to IEEE quad long double by Jakub Jelinek, jj@ultra.linux.cz.
|
|
|
|
|
*/
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* ====================================================
|
|
|
|
|
* 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 "quadmath-imp.h"
|
|
|
|
|
|
|
|
|
|
__float128
|
|
|
|
|
nextafterq (__float128 x, __float128 y)
|
|
|
|
|
{
|
|
|
|
|
int64_t hx,hy,ix,iy;
|
|
|
|
|
uint64_t lx,ly;
|
|
|
|
|
|
|
|
|
|
GET_FLT128_WORDS64(hx,lx,x);
|
|
|
|
|
GET_FLT128_WORDS64(hy,ly,y);
|
|
|
|
|
ix = hx&0x7fffffffffffffffLL; /* |x| */
|
|
|
|
|
iy = hy&0x7fffffffffffffffLL; /* |y| */
|
|
|
|
|
|
|
|
|
|
if(((ix>=0x7fff000000000000LL)&&((ix-0x7fff000000000000LL)|lx)!=0) || /* x is nan */
|
|
|
|
|
((iy>=0x7fff000000000000LL)&&((iy-0x7fff000000000000LL)|ly)!=0)) /* y is nan */
|
|
|
|
|
return x+y;
|
|
|
|
|
if(x==y) return y; /* x=y, return y */
|
|
|
|
|
if((ix|lx)==0) { /* x == 0 */
|
|
|
|
|
SET_FLT128_WORDS64(x,hy&0x8000000000000000ULL,1);/* return +-minsubnormal */
|
|
|
|
|
|
|
|
|
|
/* here we should raise an underflow flag */
|
|
|
|
|
return x;
|
|
|
|
|
}
|
|
|
|
|
if(hx>=0) { /* x > 0 */
|
|
|
|
|
if(hx>hy||((hx==hy)&&(lx>ly))) { /* x > y, x -= ulp */
|
|
|
|
|
if(lx==0) hx--;
|
|
|
|
|
lx--;
|
|
|
|
|
} else { /* x < y, x += ulp */
|
|
|
|
|
lx++;
|
|
|
|
|
if(lx==0) hx++;
|
|
|
|
|
}
|
|
|
|
|
} else { /* x < 0 */
|
|
|
|
|
if(hy>=0||hx>hy||((hx==hy)&&(lx>ly))){/* x < y, x -= ulp */
|
|
|
|
|
if(lx==0) hx--;
|
|
|
|
|
lx--;
|
|
|
|
|
} else { /* x > y, x += ulp */
|
|
|
|
|
lx++;
|
|
|
|
|
if(lx==0) hx++;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
hy = hx&0x7fff000000000000LL;
|
|
|
|
|
if(hy==0x7fff000000000000LL) return x+x;/* overflow */
|
|
|
|
|
if(hy==0) {
|
|
|
|
|
/* here we should raise an underflow flag */
|
|
|
|
|
}
|
|
|
|
|
SET_FLT128_WORDS64(x,hx,lx);
|
|
|
|
|
return x;
|
|
|
|
|
}
|
