vx32

Local 9vx git repository for patches.
git clone git://r-36.net/vx32
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s_nextafterf.c (1708B)


      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 #ifndef lint
     17 static char rcsid[] = "$FreeBSD: src/lib/msun/src/s_nextafterf.c,v 1.9 2005/01/23 22:56:08 das Exp $";
     18 #endif
     19 
     20 #include "math.h"
     21 #include "math_private.h"
     22 
     23 float
     24 nextafterf(float x, float y)
     25 {
     26 	int32_t hx,hy,ix,iy;
     27 
     28 	GET_FLOAT_WORD(hx,x);
     29 	GET_FLOAT_WORD(hy,y);
     30 	ix = hx&0x7fffffff;		/* |x| */
     31 	iy = hy&0x7fffffff;		/* |y| */
     32 
     33 	if((ix>0x7f800000) ||   /* x is nan */
     34 	   (iy>0x7f800000))     /* y is nan */
     35 	   return x+y;
     36 	if(x==y) return y;		/* x=y, return y */
     37 	if(ix==0) {				/* x == 0 */
     38 	    SET_FLOAT_WORD(x,(hy&0x80000000)|1);/* return +-minsubnormal */
     39 	    y = x*x;
     40 	    if(y==x) return y; else return x;	/* raise underflow flag */
     41 	}
     42 	if(hx>=0) {				/* x > 0 */
     43 	    if(hx>hy) {				/* x > y, x -= ulp */
     44 		hx -= 1;
     45 	    } else {				/* x < y, x += ulp */
     46 		hx += 1;
     47 	    }
     48 	} else {				/* x < 0 */
     49 	    if(hy>=0||hx>hy){			/* x < y, x -= ulp */
     50 		hx -= 1;
     51 	    } else {				/* x > y, x += ulp */
     52 		hx += 1;
     53 	    }
     54 	}
     55 	hy = hx&0x7f800000;
     56 	if(hy>=0x7f800000) return x+x;	/* overflow  */
     57 	if(hy<0x00800000) {		/* underflow */
     58 	    y = x*x;
     59 	    if(y!=x) {		/* raise underflow flag */
     60 	        SET_FLOAT_WORD(y,hx);
     61 		return y;
     62 	    }
     63 	}
     64 	SET_FLOAT_WORD(x,hx);
     65 	return x;
     66 }