| /* |
| * ==================================================== |
| * 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 <float.h> |
| |
| #include "fpmath.h" |
| #include "math.h" |
| #include "math_private.h" |
| |
| #define LDBL_INFNAN_EXP (LDBL_MAX_EXP * 2 - 1) |
| |
| float |
| nexttowardf(float x, long double y) |
| { |
| union IEEEl2bits uy; |
| volatile float t; |
| int32_t hx,ix; |
| |
| GET_FLOAT_WORD(hx,x); |
| ix = hx&0x7fffffff; /* |x| */ |
| uy.e = y; |
| |
| if((ix>0x7f800000) || |
| (uy.bits.exp == LDBL_INFNAN_EXP && |
| ((uy.bits.manh&~LDBL_NBIT)|uy.bits.manl) != 0)) |
| return x+y; /* x or y is nan */ |
| if(x==y) return (float)y; /* x=y, return y */ |
| if(ix==0) { /* x == 0 */ |
| SET_FLOAT_WORD(x,(uy.bits.sign<<31)|1);/* return +-minsubnormal */ |
| t = x*x; |
| if(t==x) return t; else return x; /* raise underflow flag */ |
| } |
| if(hx>=0 ^ x < y) /* x -= ulp */ |
| hx -= 1; |
| else /* x += ulp */ |
| hx += 1; |
| ix = hx&0x7f800000; |
| if(ix>=0x7f800000) return x+x; /* overflow */ |
| if(ix<0x00800000) { /* underflow */ |
| t = x*x; |
| if(t!=x) { /* raise underflow flag */ |
| SET_FLOAT_WORD(x,hx); |
| return x; |
| } |
| } |
| SET_FLOAT_WORD(x,hx); |
| return x; |
| } |
