GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libm/src/ld80/s_nexttoward.c Lines: 0 45 0.0 %
Date: 2017-11-13 Branches: 0 54 0.0 %

Line Branch Exec Source
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/* @(#)s_nextafter.c 5.1 93/09/24 */
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/*
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 * ====================================================
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 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
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 *
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 * Developed at SunPro, a Sun Microsystems, Inc. business.
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 * Permission to use, copy, modify, and distribute this
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 * software is freely granted, provided that this notice
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 * is preserved.
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 * ====================================================
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 */
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/* IEEE functions
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 *	nexttoward(x,y)
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 *	return the next machine floating-point number of x in the
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 *	direction toward y.
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 *   Special cases:
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 */
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#include <math.h>
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#include <float.h>
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#include "math_private.h"
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double
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nexttoward(double x, long double y)
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{
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	int32_t hx,ix,iy;
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	u_int32_t lx,hy,ly,esy;
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	EXTRACT_WORDS(hx,lx,x);
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	GET_LDOUBLE_WORDS(esy,hy,ly,y);
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	ix = hx&0x7fffffff;		/* |x| */
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	iy = esy&0x7fff;		/* |y| */
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	if(((ix>=0x7ff00000)&&((ix-0x7ff00000)|lx)!=0) ||   /* x is nan */
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	   ((iy>=0x7fff)&&(hy|ly)!=0))		/* y is nan */
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	   return x+y;
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	if((long double) x==y) return y;	/* x=y, return y */
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	if((ix|lx)==0) {			/* x == 0 */
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	    volatile double u;
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	    INSERT_WORDS(x,(esy&0x8000)<<16,1); /* return +-minsub */
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	    u = x;
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	    u = u * u;				/* raise underflow flag */
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	    return x;
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	}
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	if(hx>=0) {				/* x > 0 */
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	    if (esy>=0x8000||((ix>>20)&0x7ff)>iy-0x3c00
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		|| (((ix>>20)&0x7ff)==iy-0x3c00
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		    && (((hx<<11)|(lx>>21))>(hy&0x7fffffff)
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			|| (((hx<<11)|(lx>>21))==(hy&0x7fffffff)
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			    && (lx<<11)>ly)))) {	/* x > y, x -= ulp */
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		if(lx==0) hx -= 1;
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		lx -= 1;
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	    } else {				/* x < y, x += ulp */
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		lx += 1;
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		if(lx==0) hx += 1;
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	    }
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	} else {				/* x < 0 */
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	    if (esy<0x8000||((ix>>20)&0x7ff)>iy-0x3c00
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		|| (((ix>>20)&0x7ff)==iy-0x3c00
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		    && (((hx<<11)|(lx>>21))>(hy&0x7fffffff)
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			|| (((hx<<11)|(lx>>21))==(hy&0x7fffffff)
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			    && (lx<<11)>ly))))	{/* x < y, x -= ulp */
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		if(lx==0) hx -= 1;
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		lx -= 1;
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	    } else {				/* x > y, x += ulp */
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		lx += 1;
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		if(lx==0) hx += 1;
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	    }
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	}
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	hy = hx&0x7ff00000;
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	if(hy>=0x7ff00000) {
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	  x = x+x;	/* overflow  */
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	  return x;
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	}
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	if(hy<0x00100000) {
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	    volatile double u = x*x;		/* underflow */
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	    if(u==x) {
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		INSERT_WORDS(x,hx,lx);
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		return x;
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	    }
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	}
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	INSERT_WORDS(x,hx,lx);
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	return x;
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}