1/* s_nextafterf.c -- float version of s_nextafter.c. 2 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. 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) 17static char rcsid[] = "$NetBSD: s_nextafterf.c,v 1.4 1995/05/10 20:48:01 jtc Exp $"; 18#endif 19 20#include "math.h" 21#include "math_private.h" 22#include <float.h> 23 24#ifdef __STDC__ 25 float __nextafterf(float x, float y) 26#else 27 float __nextafterf(x,y) 28 float x,y; 29#endif 30{ 31 int32_t hx,hy,ix,iy; 32 33 GET_FLOAT_WORD(hx,x); 34 GET_FLOAT_WORD(hy,y); 35 ix = hx&0x7fffffff; /* |x| */ 36 iy = hy&0x7fffffff; /* |y| */ 37 38 if((ix>0x7f800000) || /* x is nan */ 39 (iy>0x7f800000)) /* y is nan */ 40 return x+y; 41 if(x==y) return y; /* x=y, return y */ 42 if(ix==0) { /* x == 0 */ 43 SET_FLOAT_WORD(x,(hy&0x80000000)|1);/* return +-minsubnormal */ 44 y = x*x; 45 if(y==x) return y; else return x; /* raise underflow flag */ 46 } 47 if(hx>=0) { /* x > 0 */ 48 if(hx>hy) { /* x > y, x -= ulp */ 49 hx -= 1; 50 } else { /* x < y, x += ulp */ 51 hx += 1; 52 } 53 } else { /* x < 0 */ 54 if(hy>=0||hx>hy){ /* x < y, x -= ulp */ 55 hx -= 1; 56 } else { /* x > y, x += ulp */ 57 hx += 1; 58 } 59 } 60 hy = hx&0x7f800000; 61 if(hy>=0x7f800000) { 62 x = x+x; /* overflow */ 63 if (FLT_EVAL_METHOD != 0) 64 asm ("" : "=m"(x) : "m"(x)); 65 return x; /* overflow */ 66 } 67 if(hy<0x00800000) { /* underflow */ 68 y = x*x; 69 if(y!=x) { /* raise underflow flag */ 70 SET_FLOAT_WORD(y,hx); 71 return y; 72 } 73 } 74 SET_FLOAT_WORD(x,hx); 75 return x; 76} 77weak_alias (__nextafterf, nextafterf) 78