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/* ef_hypot.c -- float version of e_hypot.c.
* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
*/
/*
* ====================================================
* 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 "fdlibm.h"
#if defined(_IEEE_LIBM) && defined(HAVE_ALIAS_ATTRIBUTE)
__strong_reference(__ieee754_hypotf, hypotf);
#endif
#ifdef __STDC__
float __ieee754_hypotf(float x, float y)
#else
float __ieee754_hypotf(x,y)
float x, y;
#endif
{
float a=x,b=y,t1,t2,y1,y2,w;
__int32_t j,k,ha,hb;
GET_FLOAT_WORD(ha,x);
ha &= 0x7fffffffL;
GET_FLOAT_WORD(hb,y);
hb &= 0x7fffffffL;
if(hb > ha) { j = ha; ha = hb; hb = j; }
SET_FLOAT_WORD(a,ha); /* a <- |a| */
SET_FLOAT_WORD(b,hb); /* b <- |b| */
if((ha-hb)>0xf000000L) {return a+b;} /* x/y > 2**30 */
k=0;
if(ha > 0x58800000L) { /* a>2**50 */
if(!FLT_UWORD_IS_FINITE(ha)) { /* Inf or NaN */
w = a+b; /* for sNaN */
if(FLT_UWORD_IS_INFINITE(ha)) w = a;
if(FLT_UWORD_IS_INFINITE(hb)) w = b;
return w;
}
/* scale a and b by 2**-68 */
ha -= 0x22000000L; hb -= 0x22000000L; k += 68;
SET_FLOAT_WORD(a,ha);
SET_FLOAT_WORD(b,hb);
}
if(hb < 0x26800000L) { /* b < 2**-50 */
if(FLT_UWORD_IS_ZERO(hb)) {
return a;
} else if(FLT_UWORD_IS_SUBNORMAL(hb)) {
SET_FLOAT_WORD(t1,0x7e800000L); /* t1=2^126 */
b *= t1;
a *= t1;
k -= 126;
} else { /* scale a and b by 2^68 */
ha += 0x22000000; /* a *= 2^68 */
hb += 0x22000000; /* b *= 2^68 */
k -= 68;
SET_FLOAT_WORD(a,ha);
SET_FLOAT_WORD(b,hb);
}
}
/* medium size a and b */
w = a-b;
if (w>b) {
SET_FLOAT_WORD(t1,ha&0xfffff000L);
t2 = a-t1;
w = __ieee754_sqrtf(t1*t1-(b*(-b)-t2*(a+t1)));
} else {
a = a+a;
SET_FLOAT_WORD(y1,hb&0xfffff000L);
y2 = b - y1;
SET_FLOAT_WORD(t1,(ha+0x00800000L)&0xfffff000UL);
t2 = a - t1;
w = __ieee754_sqrtf(t1*y1-(w*(-w)-(t1*y2+t2*b)));
}
if(k!=0) {
SET_FLOAT_WORD(t1,0x3f800000L+(k<<23));
return t1*w;
} else return w;
}
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