GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libm/src/e_fmodf.c Lines: 0 45 0.0 %
Date: 2017-11-13 Branches: 0 32 0.0 %

Line Branch Exec Source
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/* e_fmodf.c -- float version of e_fmod.c.
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 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
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 */
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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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/*
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 * fmodf(x,y)
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 * Return x mod y in exact arithmetic
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 * Method: shift and subtract
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 */
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#include "math.h"
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#include "math_private.h"
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static const float one = 1.0, Zero[] = {0.0, -0.0,};
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float
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fmodf(float x, float y)
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{
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	int32_t n,hx,hy,hz,ix,iy,sx,i;
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	GET_FLOAT_WORD(hx,x);
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	GET_FLOAT_WORD(hy,y);
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	sx = hx&0x80000000;		/* sign of x */
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	hx ^=sx;		/* |x| */
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	hy &= 0x7fffffff;	/* |y| */
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    /* purge off exception values */
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	if(hy==0||(hx>=0x7f800000)||		/* y=0,or x not finite */
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	   (hy>0x7f800000))			/* or y is NaN */
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	    return (x*y)/(x*y);
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	if(hx<hy) return x;			/* |x|<|y| return x */
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	if(hx==hy)
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	    return Zero[(u_int32_t)sx>>31];	/* |x|=|y| return x*0*/
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    /* determine ix = ilogb(x) */
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	if(hx<0x00800000) {	/* subnormal x */
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	    for (ix = -126,i=(hx<<8); i>0; i<<=1) ix -=1;
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	} else ix = (hx>>23)-127;
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    /* determine iy = ilogb(y) */
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	if(hy<0x00800000) {	/* subnormal y */
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	    for (iy = -126,i=(hy<<8); i>=0; i<<=1) iy -=1;
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	} else iy = (hy>>23)-127;
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    /* set up {hx,lx}, {hy,ly} and align y to x */
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	if(ix >= -126)
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	    hx = 0x00800000|(0x007fffff&hx);
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	else {		/* subnormal x, shift x to normal */
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	    n = -126-ix;
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	    hx = hx<<n;
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	}
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	if(iy >= -126)
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	    hy = 0x00800000|(0x007fffff&hy);
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	else {		/* subnormal y, shift y to normal */
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	    n = -126-iy;
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	    hy = hy<<n;
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	}
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    /* fix point fmod */
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	n = ix - iy;
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	while(n--) {
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	    hz=hx-hy;
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	    if(hz<0){hx = hx+hx;}
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	    else {
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	    	if(hz==0) 		/* return sign(x)*0 */
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		    return Zero[(u_int32_t)sx>>31];
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	    	hx = hz+hz;
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	    }
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	}
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	hz=hx-hy;
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	if(hz>=0) {hx=hz;}
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    /* convert back to floating value and restore the sign */
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	if(hx==0) 			/* return sign(x)*0 */
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	    return Zero[(u_int32_t)sx>>31];
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	while(hx<0x00800000) {		/* normalize x */
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	    hx = hx+hx;
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	    iy -= 1;
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	}
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	if(iy>= -126) {		/* normalize output */
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	    hx = ((hx-0x00800000)|((iy+127)<<23));
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	    SET_FLOAT_WORD(x,hx|sx);
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	} else {		/* subnormal output */
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	    n = -126 - iy;
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	    hx >>= n;
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	    SET_FLOAT_WORD(x,hx|sx);
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	    x *= one;		/* create necessary signal */
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	}
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	return x;		/* exact output */
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}
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DEF_STD(fmodf);