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Diffstat (limited to 'sysdeps/libm-ieee754/e_hypotl.c')
| -rw-r--r-- | sysdeps/libm-ieee754/e_hypotl.c | 133 |
1 files changed, 0 insertions, 133 deletions
diff --git a/sysdeps/libm-ieee754/e_hypotl.c b/sysdeps/libm-ieee754/e_hypotl.c deleted file mode 100644 index 1a40c556dc..0000000000 --- a/sysdeps/libm-ieee754/e_hypotl.c +++ /dev/null @@ -1,133 +0,0 @@ -/* e_hypotl.c -- long double version of e_hypot.c. - * Conversion to long double by Ulrich Drepper, - * Cygnus Support, drepper@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. - * ==================================================== - */ - -#if defined(LIBM_SCCS) && !defined(lint) -static char rcsid[] = "$NetBSD: $"; -#endif - -/* __ieee754_hypotl(x,y) - * - * Method : - * If (assume round-to-nearest) z=x*x+y*y - * has error less than sqrt(2)/2 ulp, than - * sqrt(z) has error less than 1 ulp (exercise). - * - * So, compute sqrt(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 32 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 32 bits cleared, t2 = 2x-t1, - * y1= y with lower 32 bits chopped, y2 = y-y1. - * - * NOTE: scaling may be necessary if some argument is too - * large or too tiny - * - * Special cases: - * hypot(x,y) is INF if x or y is +INF or -INF; else - * hypot(x,y) is NAN if x or y is NAN. - * - * Accuracy: - * hypot(x,y) returns sqrt(x^2+y^2) with error less - * than 1 ulps (units in the last place) - */ - -#include "math.h" -#include "math_private.h" - -#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; - u_int32_t j,k,ea,eb; - - GET_LDOUBLE_EXP(ea,x); - ea &= 0x7fff; - GET_LDOUBLE_EXP(eb,y); - eb &= 0x7fff; - if(eb > ea) {a=y;b=x;j=ea; ea=eb;eb=j;} else {a=x;b=y;} - SET_LDOUBLE_EXP(a,ea); /* a <- |a| */ - SET_LDOUBLE_EXP(b,eb); /* b <- |b| */ - if((ea-eb)>0x46) {return a+b;} /* x/y > 2**70 */ - k=0; - if(ea > 0x5f3f) { /* a>2**8000 */ - if(ea == 0x7fff) { /* Inf or NaN */ - u_int32_t exp,high,low; - w = a+b; /* for sNaN */ - GET_LDOUBLE_WORDS(exp,high,low,a); - if(((high&0x7fffffff)|low)==0) w = a; - GET_LDOUBLE_WORDS(exp,high,low,b); - if(((eb^0x7fff)|(high&0x7fffffff)|low)==0) w = b; - return w; - } - /* scale a and b by 2**-9600 */ - ea -= 0x2580; eb -= 0x2580; k += 9600; - SET_LDOUBLE_EXP(a,ea); - SET_LDOUBLE_EXP(b,eb); - } - if(eb < 0x20bf) { /* b < 2**-8000 */ - if(eb == 0) { /* subnormal b or 0 */ - u_int32_t exp,high,low; - GET_LDOUBLE_WORDS(exp,high,low,b); - if((high|low)==0) return a; - SET_LDOUBLE_WORDS(t1, 0x7ffd, 0, 0); /* t1=2^16382 */ - b *= t1; - a *= t1; - k -= 16382; - } else { /* scale a and b by 2^9600 */ - ea += 0x2580; /* a *= 2^9600 */ - eb += 0x2580; /* b *= 2^9600 */ - k -= 9600; - SET_LDOUBLE_EXP(a,ea); - SET_LDOUBLE_EXP(b,eb); - } - } - /* medium size a and b */ - w = a-b; - if (w>b) { - u_int32_t high; - GET_LDOUBLE_MSW(high,a); - SET_LDOUBLE_WORDS(t1,ea,high,0); - t2 = a-t1; - w = __ieee754_sqrtl(t1*t1-(b*(-b)-t2*(a+t1))); - } else { - u_int32_t high; - GET_LDOUBLE_MSW(high,b); - a = a+a; - SET_LDOUBLE_WORDS(y1,eb,high,0); - y2 = b - y1; - GET_LDOUBLE_MSW(high,a); - SET_LDOUBLE_WORDS(t1,ea+1,high,0); - t2 = a - t1; - w = __ieee754_sqrtl(t1*y1-(w*(-w)-(t1*y2+t2*b))); - } - if(k!=0) { - u_int32_t exp; - t1 = 1.0; - GET_LDOUBLE_EXP(exp,t1); - SET_LDOUBLE_EXP(t1,exp+k); - return t1*w; - } else return w; -} |