\left(1 + t \cdot 1.999999999999999958195573448069207123682 \cdot 10^{-16}\right) \cdot \left(1 + t \cdot 1.999999999999999958195573448069207123682 \cdot 10^{-16}\right) + \left(-1 - 2 \cdot \left(t \cdot 1.999999999999999958195573448069207123682 \cdot 10^{-16}\right)\right)\left(\left|t\right| \cdot 3.999999999999999676487027278085939408227 \cdot 10^{-32}\right) \cdot \sqrt{{t}^{2}}double f(double t) {
double r43160 = 1.0;
double r43161 = t;
double r43162 = 2e-16;
double r43163 = r43161 * r43162;
double r43164 = r43160 + r43163;
double r43165 = r43164 * r43164;
double r43166 = -1.0;
double r43167 = 2.0;
double r43168 = r43167 * r43163;
double r43169 = r43166 - r43168;
double r43170 = r43165 + r43169;
return r43170;
}
double f(double t) {
double r43171 = t;
double r43172 = fabs(r43171);
double r43173 = 3.9999999999999997e-32;
double r43174 = r43172 * r43173;
double r43175 = 2.0;
double r43176 = pow(r43171, r43175);
double r43177 = sqrt(r43176);
double r43178 = r43174 * r43177;
return r43178;
}




Bits error versus t
Results
| Original | 61.8 |
|---|---|
| Target | 50.6 |
| Herbie | 0.3 |
Initial program 61.8
Simplified50.6
Taylor expanded around 0 0.3
rmApplied add-sqr-sqrt0.3
Applied associate-*r*0.3
Simplified0.3
Final simplification0.3
herbie shell --seed 2019326 +o rules:numerics
(FPCore (t)
:name "fma_test1"
:precision binary64
:pre (<= 0.9 t 1.1)
:herbie-target
(fma (+ 1 (* t 2e-16)) (+ 1 (* t 2e-16)) (- -1 (* 2 (* t 2e-16))))
(+ (* (+ 1 (* t 2e-16)) (+ 1 (* t 2e-16))) (- -1 (* 2 (* t 2e-16)))))