1 /* s_nextafterl.c -- long double version of s_nextafter.c. 2 * Conversion to IEEE quad long double by Jakub Jelinek, jj@ultra.linux.cz. 3 */ 4 5 /* 6 * ==================================================== 7 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 8 * 9 * Developed at SunPro, a Sun Microsystems, Inc. business. 10 * Permission to use, copy, modify, and distribute this 11 * software is freely granted, provided that this notice 12 * is preserved. 13 * ==================================================== 14 */ 15 16 #if defined(LIBM_SCCS) && !defined(lint) 17 static char rcsid[] = "NetBSD: "; 18 #endif 19 20 /* IEEE functions 21 * nextafterq(x,y) 22 * return the next machine floating-point number of x in the 23 * direction toward y. 24 * Special cases: 25 */ 26 27 #include "quadmath-imp.h" 28 29 __float128 nextafterq(__float128 x, __float128 y) 30 { 31 int64_t hx,hy,ix,iy; 32 uint64_t lx,ly; 33 34 GET_FLT128_WORDS64(hx,lx,x); 35 GET_FLT128_WORDS64(hy,ly,y); 36 ix = hx&0x7fffffffffffffffLL; /* |x| */ 37 iy = hy&0x7fffffffffffffffLL; /* |y| */ 38 39 if(((ix>=0x7fff000000000000LL)&&((ix-0x7fff000000000000LL)|lx)!=0) || /* x is nan */ 40 ((iy>=0x7fff000000000000LL)&&((iy-0x7fff000000000000LL)|ly)!=0)) /* y is nan */ 41 return x+y; 42 if(x==y) return y; /* x=y, return y */ 43 if((ix|lx)==0) { /* x == 0 */ 44 __float128 u; 45 SET_FLT128_WORDS64(x,hy&0x8000000000000000ULL,1);/* return +-minsubnormal */ 46 u = math_opt_barrier (x); 47 u = u * u; 48 math_force_eval (u); /* raise underflow flag */ 49 return x; 50 } 51 if(hx>=0) { /* x > 0 */ 52 if(hx>hy||((hx==hy)&&(lx>ly))) { /* x > y, x -= ulp */ 53 if(lx==0) hx--; 54 lx--; 55 } else { /* x < y, x += ulp */ 56 lx++; 57 if(lx==0) hx++; 58 } 59 } else { /* x < 0 */ 60 if(hy>=0||hx>hy||((hx==hy)&&(lx>ly))){/* x < y, x -= ulp */ 61 if(lx==0) hx--; 62 lx--; 63 } else { /* x > y, x += ulp */ 64 lx++; 65 if(lx==0) hx++; 66 } 67 } 68 hy = hx&0x7fff000000000000LL; 69 if(hy==0x7fff000000000000LL) { 70 __float128 u = x + x; /* overflow */ 71 math_force_eval (u); 72 errno = ERANGE; 73 } 74 if(hy==0) { 75 __float128 u = x*x; /* underflow */ 76 math_force_eval (u); /* raise underflow flag */ 77 errno = ERANGE; 78 } 79 SET_FLT128_WORDS64(x,hx,lx); 80 return x; 81 } 82