| Index: fusl/src/math/sqrt.c
|
| diff --git a/fusl/src/math/sqrt.c b/fusl/src/math/sqrt.c
|
| index b27756738595dc29a8a7f35e7bffa8da64214826..ff184fa7f08787e47cf524d5dbf066c6103d321e 100644
|
| --- a/fusl/src/math/sqrt.c
|
| +++ b/fusl/src/math/sqrt.c
|
| @@ -80,106 +80,105 @@
|
|
|
| static const double tiny = 1.0e-300;
|
|
|
| -double sqrt(double x)
|
| -{
|
| - double z;
|
| - int32_t sign = (int)0x80000000;
|
| - int32_t ix0,s0,q,m,t,i;
|
| - uint32_t r,t1,s1,ix1,q1;
|
| +double sqrt(double x) {
|
| + double z;
|
| + int32_t sign = (int)0x80000000;
|
| + int32_t ix0, s0, q, m, t, i;
|
| + uint32_t r, t1, s1, ix1, q1;
|
|
|
| - EXTRACT_WORDS(ix0, ix1, x);
|
| + EXTRACT_WORDS(ix0, ix1, x);
|
|
|
| - /* take care of Inf and NaN */
|
| - if ((ix0&0x7ff00000) == 0x7ff00000) {
|
| - return x*x + x; /* sqrt(NaN)=NaN, sqrt(+inf)=+inf, sqrt(-inf)=sNaN */
|
| - }
|
| - /* take care of zero */
|
| - if (ix0 <= 0) {
|
| - if (((ix0&~sign)|ix1) == 0)
|
| - return x; /* sqrt(+-0) = +-0 */
|
| - if (ix0 < 0)
|
| - return (x-x)/(x-x); /* sqrt(-ve) = sNaN */
|
| - }
|
| - /* normalize x */
|
| - m = ix0>>20;
|
| - if (m == 0) { /* subnormal x */
|
| - while (ix0 == 0) {
|
| - m -= 21;
|
| - ix0 |= (ix1>>11);
|
| - ix1 <<= 21;
|
| - }
|
| - for (i=0; (ix0&0x00100000) == 0; i++)
|
| - ix0<<=1;
|
| - m -= i - 1;
|
| - ix0 |= ix1>>(32-i);
|
| - ix1 <<= i;
|
| - }
|
| - m -= 1023; /* unbias exponent */
|
| - ix0 = (ix0&0x000fffff)|0x00100000;
|
| - if (m & 1) { /* odd m, double x to make it even */
|
| - ix0 += ix0 + ((ix1&sign)>>31);
|
| - ix1 += ix1;
|
| - }
|
| - m >>= 1; /* m = [m/2] */
|
| + /* take care of Inf and NaN */
|
| + if ((ix0 & 0x7ff00000) == 0x7ff00000) {
|
| + return x * x + x; /* sqrt(NaN)=NaN, sqrt(+inf)=+inf, sqrt(-inf)=sNaN */
|
| + }
|
| + /* take care of zero */
|
| + if (ix0 <= 0) {
|
| + if (((ix0 & ~sign) | ix1) == 0)
|
| + return x; /* sqrt(+-0) = +-0 */
|
| + if (ix0 < 0)
|
| + return (x - x) / (x - x); /* sqrt(-ve) = sNaN */
|
| + }
|
| + /* normalize x */
|
| + m = ix0 >> 20;
|
| + if (m == 0) { /* subnormal x */
|
| + while (ix0 == 0) {
|
| + m -= 21;
|
| + ix0 |= (ix1 >> 11);
|
| + ix1 <<= 21;
|
| + }
|
| + for (i = 0; (ix0 & 0x00100000) == 0; i++)
|
| + ix0 <<= 1;
|
| + m -= i - 1;
|
| + ix0 |= ix1 >> (32 - i);
|
| + ix1 <<= i;
|
| + }
|
| + m -= 1023; /* unbias exponent */
|
| + ix0 = (ix0 & 0x000fffff) | 0x00100000;
|
| + if (m & 1) { /* odd m, double x to make it even */
|
| + ix0 += ix0 + ((ix1 & sign) >> 31);
|
| + ix1 += ix1;
|
| + }
|
| + m >>= 1; /* m = [m/2] */
|
|
|
| - /* generate sqrt(x) bit by bit */
|
| - ix0 += ix0 + ((ix1&sign)>>31);
|
| - ix1 += ix1;
|
| - q = q1 = s0 = s1 = 0; /* [q,q1] = sqrt(x) */
|
| - r = 0x00200000; /* r = moving bit from right to left */
|
| + /* generate sqrt(x) bit by bit */
|
| + ix0 += ix0 + ((ix1 & sign) >> 31);
|
| + ix1 += ix1;
|
| + q = q1 = s0 = s1 = 0; /* [q,q1] = sqrt(x) */
|
| + r = 0x00200000; /* r = moving bit from right to left */
|
|
|
| - while (r != 0) {
|
| - t = s0 + r;
|
| - if (t <= ix0) {
|
| - s0 = t + r;
|
| - ix0 -= t;
|
| - q += r;
|
| - }
|
| - ix0 += ix0 + ((ix1&sign)>>31);
|
| - ix1 += ix1;
|
| - r >>= 1;
|
| - }
|
| + while (r != 0) {
|
| + t = s0 + r;
|
| + if (t <= ix0) {
|
| + s0 = t + r;
|
| + ix0 -= t;
|
| + q += r;
|
| + }
|
| + ix0 += ix0 + ((ix1 & sign) >> 31);
|
| + ix1 += ix1;
|
| + r >>= 1;
|
| + }
|
|
|
| - r = sign;
|
| - while (r != 0) {
|
| - t1 = s1 + r;
|
| - t = s0;
|
| - if (t < ix0 || (t == ix0 && t1 <= ix1)) {
|
| - s1 = t1 + r;
|
| - if ((t1&sign) == sign && (s1&sign) == 0)
|
| - s0++;
|
| - ix0 -= t;
|
| - if (ix1 < t1)
|
| - ix0--;
|
| - ix1 -= t1;
|
| - q1 += r;
|
| - }
|
| - ix0 += ix0 + ((ix1&sign)>>31);
|
| - ix1 += ix1;
|
| - r >>= 1;
|
| - }
|
| + r = sign;
|
| + while (r != 0) {
|
| + t1 = s1 + r;
|
| + t = s0;
|
| + if (t < ix0 || (t == ix0 && t1 <= ix1)) {
|
| + s1 = t1 + r;
|
| + if ((t1 & sign) == sign && (s1 & sign) == 0)
|
| + s0++;
|
| + ix0 -= t;
|
| + if (ix1 < t1)
|
| + ix0--;
|
| + ix1 -= t1;
|
| + q1 += r;
|
| + }
|
| + ix0 += ix0 + ((ix1 & sign) >> 31);
|
| + ix1 += ix1;
|
| + r >>= 1;
|
| + }
|
|
|
| - /* use floating add to find out rounding direction */
|
| - if ((ix0|ix1) != 0) {
|
| - z = 1.0 - tiny; /* raise inexact flag */
|
| - if (z >= 1.0) {
|
| - z = 1.0 + tiny;
|
| - if (q1 == (uint32_t)0xffffffff) {
|
| - q1 = 0;
|
| - q++;
|
| - } else if (z > 1.0) {
|
| - if (q1 == (uint32_t)0xfffffffe)
|
| - q++;
|
| - q1 += 2;
|
| - } else
|
| - q1 += q1 & 1;
|
| - }
|
| - }
|
| - ix0 = (q>>1) + 0x3fe00000;
|
| - ix1 = q1>>1;
|
| - if (q&1)
|
| - ix1 |= sign;
|
| - ix0 += m << 20;
|
| - INSERT_WORDS(z, ix0, ix1);
|
| - return z;
|
| + /* use floating add to find out rounding direction */
|
| + if ((ix0 | ix1) != 0) {
|
| + z = 1.0 - tiny; /* raise inexact flag */
|
| + if (z >= 1.0) {
|
| + z = 1.0 + tiny;
|
| + if (q1 == (uint32_t)0xffffffff) {
|
| + q1 = 0;
|
| + q++;
|
| + } else if (z > 1.0) {
|
| + if (q1 == (uint32_t)0xfffffffe)
|
| + q++;
|
| + q1 += 2;
|
| + } else
|
| + q1 += q1 & 1;
|
| + }
|
| + }
|
| + ix0 = (q >> 1) + 0x3fe00000;
|
| + ix1 = q1 >> 1;
|
| + if (q & 1)
|
| + ix1 |= sign;
|
| + ix0 += m << 20;
|
| + INSERT_WORDS(z, ix0, ix1);
|
| + return z;
|
| }
|
|
|