diff options
| -rw-r--r-- | ChangeLog | 6 | ||||
| -rw-r--r-- | sysdeps/ieee754/flt-32/e_hypotf.c | 77 |
2 files changed, 31 insertions, 52 deletions
diff --git a/ChangeLog b/ChangeLog index b8f1fe53ca..b65f68af6b 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,9 @@ +2012-03-13 David S. Miller <davem@davemloft.net> + + [BZ #13840] + * sysdeps/ieee754/flt-32/e_hypotf.c (__ieee754_hypotf): Rewrite to use + double-precision for the calculation instead of scaling. + 2012-03-13 Joseph Myers <joseph@codesourcery.com> * sysdeps/ieee754/dbl-64/s_nearbyint.c (__nearbyint): Do not diff --git a/sysdeps/ieee754/flt-32/e_hypotf.c b/sysdeps/ieee754/flt-32/e_hypotf.c index 97e7d34b64..8f499b5fde 100644 --- a/sysdeps/ieee754/flt-32/e_hypotf.c +++ b/sysdeps/ieee754/flt-32/e_hypotf.c @@ -19,62 +19,35 @@ float __ieee754_hypotf(float x, float y) { - float a,b,t1,t2,y1,y2,w; - int32_t j,k,ha,hb; + double d_x, d_y; + int32_t ha, hb; GET_FLOAT_WORD(ha,x); ha &= 0x7fffffff; GET_FLOAT_WORD(hb,y); hb &= 0x7fffffff; - if(hb > ha) {a=y;b=x;j=ha; ha=hb;hb=j;} else {a=x;b=y;} - SET_FLOAT_WORD(a,ha); /* a <- |a| */ - SET_FLOAT_WORD(b,hb); /* b <- |b| */ - if((ha-hb)>0xf000000) {return a+b;} /* x/y > 2**30 */ - k=0; - if(__builtin_expect(ha > 0x58800000, 0)) { /* a>2**50 */ - if(ha >= 0x7f800000) { /* Inf or NaN */ - w = a+b; /* for sNaN */ - if(ha == 0x7f800000) w = a; - if(hb == 0x7f800000) w = b; - return w; - } - /* scale a and b by 2**-60 */ - ha -= 0x1e000000; hb -= 0x1e000000; k += 60; - SET_FLOAT_WORD(a,ha); - SET_FLOAT_WORD(b,hb); - } - if(__builtin_expect(hb < 0x26800000, 0)) { /* b < 2**-50 */ - if(hb <= 0x007fffff) { /* subnormal b or 0 */ - if(hb==0) return a; - SET_FLOAT_WORD(t1,0x7e800000); /* t1=2^126 */ - b *= t1; - a *= t1; - k -= 126; - } else { /* scale a and b by 2^60 */ - ha += 0x1e000000; /* a *= 2^60 */ - hb += 0x1e000000; /* b *= 2^60 */ - k -= 60; - 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&0xfffff000); - t2 = a-t1; - w = __ieee754_sqrtf(t1*t1-(b*(-b)-t2*(a+t1))); - } else { - a = a+a; - SET_FLOAT_WORD(y1,hb&0xfffff000); - y2 = b - y1; - SET_FLOAT_WORD(t1,ha+0x00800000); - t2 = a - t1; - w = __ieee754_sqrtf(t1*y1-(w*(-w)-(t1*y2+t2*b))); - } - if(k!=0) { - SET_FLOAT_WORD(t1,0x3f800000+(k<<23)); - return t1*w; - } else return w; + if (ha == 0x7f800000) + { + if (x == y) + return fabsf(y); + return fabsf(x); + } + else if (hb == 0x7f800000) + { + if (x == y) + return fabsf(x); + return fabsf(y); + } + else if (ha > 0x7f800000 || hb > 0x7f800000) + return fabsf(x) * fabsf(y); + else if (ha == 0) + return fabsf(y); + else if (hb == 0) + return fabsf(x); + + d_x = (double) x; + d_y = (double) y; + + return (float) __ieee754_sqrt(d_x * d_x + d_y * d_y); } strong_alias (__ieee754_hypotf, __hypotf_finite) |