\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)t \cdot \left(t \cdot 3.999999999999999676487027278085939408227 \cdot 10^{-32}\right)double f(double t) {
double r3163720 = 1.0;
double r3163721 = t;
double r3163722 = 2e-16;
double r3163723 = r3163721 * r3163722;
double r3163724 = r3163720 + r3163723;
double r3163725 = r3163724 * r3163724;
double r3163726 = -1.0;
double r3163727 = 2.0;
double r3163728 = r3163727 * r3163723;
double r3163729 = r3163726 - r3163728;
double r3163730 = r3163725 + r3163729;
return r3163730;
}
double f(double t) {
double r3163731 = t;
double r3163732 = 3.9999999999999997e-32;
double r3163733 = r3163731 * r3163732;
double r3163734 = r3163731 * r3163733;
return r3163734;
}




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
Simplified0.3
Taylor expanded around 0 0.3
Simplified0.3
Final simplification0.3
herbie shell --seed 2019172 +o rules:numerics
(FPCore (t)
:name "fma_test1"
:pre (<= 0.9 t 1.1)
:herbie-target
(fma (+ 1.0 (* t 2e-16)) (+ 1.0 (* t 2e-16)) (- -1.0 (* 2.0 (* t 2e-16))))
(+ (* (+ 1.0 (* t 2e-16)) (+ 1.0 (* t 2e-16))) (- -1.0 (* 2.0 (* t 2e-16)))))