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Diffstat (limited to 'sysdeps/ieee754/ldbl-128ibm/e_hypotl.c')
-rw-r--r--sysdeps/ieee754/ldbl-128ibm/e_hypotl.c88
1 files changed, 48 insertions, 40 deletions
diff --git a/sysdeps/ieee754/ldbl-128ibm/e_hypotl.c b/sysdeps/ieee754/ldbl-128ibm/e_hypotl.c
index 768bd3b..3b07a47 100644
--- a/sysdeps/ieee754/ldbl-128ibm/e_hypotl.c
+++ b/sysdeps/ieee754/ldbl-128ibm/e_hypotl.c
@@ -45,76 +45,84 @@
#include <math.h>
#include <math_private.h>
-static const long double two600 = 0x1.0p+600L;
-static const long double two1022 = 0x1.0p+1022L;
-
long double
__ieee754_hypotl(long double x, long double y)
{
- long double a,b,t1,t2,y1,y2,w,kld;
+ long double a,b,a1,a2,b1,b2,w,kld;
int64_t j,k,ha,hb;
+ double xhi, yhi, hi, lo;
- GET_LDOUBLE_MSW64(ha,x);
+ xhi = ldbl_high (x);
+ EXTRACT_WORDS64 (ha, xhi);
+ yhi = ldbl_high (y);
+ EXTRACT_WORDS64 (hb, yhi);
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)>0x780000000000000LL) {return a+b;} /* x/y > 2**120 */
+ if((ha-hb)>0x0780000000000000LL) {return a+b;} /* x/y > 2**120 */
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)
+ if(ha == 0x7ff0000000000000LL)
w = a;
- GET_LDOUBLE_LSW64(low,b);
- if(((hb^0x7ff0000000000000LL)|(low&0x7fffffffffffffffLL))==0)
+ if(hb == 0x7ff0000000000000LL)
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;
+ a *= 0x1p-600L;
+ b *= 0x1p-600L;
+ k = 600;
+ kld = 0x1p+600L;
}
- if(hb < 0x23d0000000000000LL) { /* b < 2**-450 */
+ else if(hb < 0x23d0000000000000LL) { /* b < 2**-450 */
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;
+ if(hb==0) return a;
+ a *= 0x1p+1022L;
+ b *= 0x1p+1022L;
+ k = -1022;
+ kld = 0x1p-1022L;
} 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;
+ a *= 0x1p+600L;
+ b *= 0x1p+600L;
+ k = -600;
+ kld = 0x1p-600L;
}
}
/* 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)));
+ ldbl_unpack (a, &hi, &lo);
+ a1 = hi;
+ a2 = lo;
+ /* a*a + b*b
+ = (a1+a2)*a + b*b
+ = a1*a + a2*a + b*b
+ = a1*(a1+a2) + a2*a + b*b
+ = a1*a1 + a1*a2 + a2*a + b*b
+ = a1*a1 + a2*(a+a1) + b*b */
+ w = __ieee754_sqrtl(a1*a1-(b*(-b)-a2*(a+a1)));
} 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)));
+ ldbl_unpack (b, &hi, &lo);
+ b1 = hi;
+ b2 = lo;
+ ldbl_unpack (a, &hi, &lo);
+ a1 = hi;
+ a2 = lo;
+ /* a*a + b*b
+ = a*a + (a-b)*(a-b) - (a-b)*(a-b) + b*b
+ = a*a + w*w - (a*a - 2*a*b + b*b) + b*b
+ = w*w + 2*a*b
+ = w*w + (a1+a2)*b
+ = w*w + a1*b + a2*b
+ = w*w + a1*(b1+b2) + a2*b
+ = w*w + a1*b1 + a1*b2 + a2*b */
+ w = __ieee754_sqrtl(a1*b1-(w*(-w)-(a1*b2+a2*b)));
}
if(k!=0)
return w*kld;