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Diffstat (limited to 'sysdeps/ieee754/ldbl-128ibm/e_hypotl.c')
| -rw-r--r-- | sysdeps/ieee754/ldbl-128ibm/e_hypotl.c | 131 |
1 files changed, 0 insertions, 131 deletions
diff --git a/sysdeps/ieee754/ldbl-128ibm/e_hypotl.c b/sysdeps/ieee754/ldbl-128ibm/e_hypotl.c deleted file mode 100644 index 4330f28..0000000 --- a/sysdeps/ieee754/ldbl-128ibm/e_hypotl.c +++ /dev/null @@ -1,131 +0,0 @@ -/* @(#)e_hypotl.c 5.1 93/09/24 */ -/* - * ==================================================== - * 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. - * ==================================================== - */ - -#if defined(LIBM_SCCS) && !defined(lint) -static char rcsid[] = "$NetBSD: e_hypotl.c,v 1.9 1995/05/12 04:57:27 jtc Exp $"; -#endif - -/* __ieee754_hypotl(x,y) - * - * Method : - * If (assume round-to-nearest) z=x*x+y*y - * has error less than sqrtl(2)/2 ulp, than - * sqrtl(z) has error less than 1 ulp (exercise). - * - * So, compute sqrtl(x*x+y*y) with some care as - * follows to get the error below 1 ulp: - * - * Assume x>y>0; - * (if possible, set rounding to round-to-nearest) - * 1. if x > 2y use - * x1*x1+(y*y+(x2*(x+x1))) for x*x+y*y - * where x1 = x with lower 53 bits cleared, x2 = x-x1; else - * 2. if x <= 2y use - * t1*y1+((x-y)*(x-y)+(t1*y2+t2*y)) - * where t1 = 2x with lower 53 bits cleared, t2 = 2x-t1, - * y1= y with lower 53 bits chopped, y2 = y-y1. - * - * NOTE: scaling may be necessary if some argument is too - * large or too tiny - * - * Special cases: - * hypotl(x,y) is INF if x or y is +INF or -INF; else - * hypotl(x,y) is NAN if x or y is NAN. - * - * Accuracy: - * hypotl(x,y) returns sqrtl(x^2+y^2) with error less - * than 1 ulps (units in the last place) - */ - -#include "math.h" -#include "math_private.h" - -static const long double two600 = 0x1.0p+600L; -static const long double two1022 = 0x1.0p+1022L; - -#ifdef __STDC__ - long double __ieee754_hypotl(long double x, long double y) -#else - long double __ieee754_hypotl(x,y) - long double x, y; -#endif -{ - long double a,b,t1,t2,y1,y2,w,kld; - int64_t j,k,ha,hb; - - GET_LDOUBLE_MSW64(ha,x); - ha &= 0x7fffffffffffffffLL; - GET_LDOUBLE_MSW64(hb,y); - hb &= 0x7fffffffffffffffLL; - if(hb > ha) {a=y;b=x;j=ha; ha=hb;hb=j;} else {a=x;b=y;} - a = fabsl(a); /* a <- |a| */ - b = fabsl(b); /* b <- |b| */ - if((ha-hb)>0x3c0000000000000LL) {return a+b;} /* x/y > 2**60 */ - k=0; - kld = 1.0L; - if(ha > 0x5f30000000000000LL) { /* a>2**500 */ - if(ha >= 0x7ff0000000000000LL) { /* Inf or NaN */ - u_int64_t low; - w = a+b; /* for sNaN */ - GET_LDOUBLE_LSW64(low,a); - if(((ha&0xfffffffffffffLL)|(low&0x7fffffffffffffffLL))==0) - w = a; - GET_LDOUBLE_LSW64(low,b); - if(((hb^0x7ff0000000000000LL)|(low&0x7fffffffffffffffLL))==0) - w = b; - return w; - } - /* scale a and b by 2**-600 */ - ha -= 0x2580000000000000LL; hb -= 0x2580000000000000LL; k += 600; - a /= two600; - b /= two600; - k += 600; - kld = two600; - } - if(hb < 0x20b0000000000000LL) { /* b < 2**-500 */ - if(hb <= 0x000fffffffffffffLL) { /* subnormal b or 0 */ - u_int64_t low; - GET_LDOUBLE_LSW64(low,b); - if((hb|(low&0x7fffffffffffffffLL))==0) return a; - t1=two1022; /* t1=2^1022 */ - b *= t1; - a *= t1; - k -= 1022; - kld = kld / two1022; - } else { /* scale a and b by 2^600 */ - ha += 0x2580000000000000LL; /* a *= 2^600 */ - hb += 0x2580000000000000LL; /* b *= 2^600 */ - k -= 600; - a *= two600; - b *= two600; - kld = kld / two600; - } - } - /* medium size a and b */ - w = a-b; - if (w>b) { - SET_LDOUBLE_WORDS64(t1,ha,0); - t2 = a-t1; - w = __ieee754_sqrtl(t1*t1-(b*(-b)-t2*(a+t1))); - } else { - a = a+a; - SET_LDOUBLE_WORDS64(y1,hb,0); - y2 = b - y1; - SET_LDOUBLE_WORDS64(t1,ha+0x0010000000000000LL,0); - t2 = a - t1; - w = __ieee754_sqrtl(t1*y1-(w*(-w)-(t1*y2+t2*b))); - } - if(k!=0) - return w*kld; - else - return w; -} |