| /* s_nextafterf.c -- float version of s_nextafter.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 <sys/cdefs.h> |
| __FBSDID("$FreeBSD$"); |
| |
| #include "math.h" |
| #include "math_private.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) return y; /* x=y, return y */ |
| if(ix==0) { /* x == 0 */ |
| SET_FLOAT_WORD(x,(hy&0x80000000)|1);/* return +-minsubnormal */ |
| t = x*x; |
| if(t==x) return t; else return x; /* raise underflow flag */ |
| } |
| if(hx>=0) { /* x > 0 */ |
| if(hx>hy) { /* x > y, x -= ulp */ |
| hx -= 1; |
| } else { /* x < y, x += ulp */ |
| hx += 1; |
| } |
| } else { /* x < 0 */ |
| if(hy>=0||hx>hy){ /* x < y, x -= ulp */ |
| hx -= 1; |
| } else { /* x > y, x += ulp */ |
| hx += 1; |
| } |
| } |
| hy = hx&0x7f800000; |
| if(hy>=0x7f800000) return x+x; /* overflow */ |
| if(hy<0x00800000) { /* underflow */ |
| t = x*x; |
| if(t!=x) { /* raise underflow flag */ |
| SET_FLOAT_WORD(y,hx); |
| return y; |
| } |
| } |
| SET_FLOAT_WORD(x,hx); |
| return x; |
| } |
