| /* Single precision version of nexttoward.c. |
| Conversion to IEEE single float 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. |
| * ==================================================== |
| */ |
| |
| /* IEEE functions |
| * nexttowardf(x,y) |
| * return the next machine floating-point number of x in the |
| * direction toward y. |
| * This is for machines which use the same binary type for double and |
| * long double. |
| * Special cases: |
| */ |
| |
| #include <errno.h> |
| #include <math.h> |
| #include <math_private.h> |
| #include <float.h> |
| |
| float __nexttowardf(float x, long double y) |
| { |
| int32_t hx,hy,ix,iy; |
| u_int32_t ly; |
| |
| GET_FLOAT_WORD(hx,x); |
| EXTRACT_WORDS(hy,ly,y); |
| ix = hx&0x7fffffff; /* |x| */ |
| iy = hy&0x7fffffff; /* |y| */ |
| |
| if((ix>0x7f800000) || /* x is nan */ |
| ((iy>=0x7ff00000)&&((iy-0x7ff00000)|ly)!=0)) /* y is nan */ |
| return x+y; |
| if((long double) x==y) return y; /* x=y, return y */ |
| if(ix==0) { /* x == 0 */ |
| float u; |
| SET_FLOAT_WORD(x,(u_int32_t)(hy&0x80000000)|1);/* return +-minsub*/ |
| u = math_opt_barrier (x); |
| u = u * u; |
| math_force_eval (u); /* raise underflow flag */ |
| return x; |
| } |
| if(hx>=0) { /* x > 0 */ |
| if(x > y) /* x -= ulp */ |
| hx -= 1; |
| else /* x < y, x += ulp */ |
| hx += 1; |
| } else { /* x < 0 */ |
| if(x < y) /* x -= ulp */ |
| hx -= 1; |
| else /* x > y, x += ulp */ |
| hx += 1; |
| } |
| hy = hx&0x7f800000; |
| if(hy>=0x7f800000) { |
| float u = x+x; /* overflow */ |
| math_force_eval (u); |
| __set_errno (ERANGE); |
| } |
| if(hy<0x00800000) { |
| float u = x*x; /* underflow */ |
| math_force_eval (u); /* raise underflow flag */ |
| __set_errno (ERANGE); |
| } |
| SET_FLOAT_WORD(x,hx); |
| return x; |
| } |
| weak_alias (__nexttowardf, nexttowardf) |