\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(3.999999999999999676487027278085939408227 \cdot 10^{-32} \cdot t\right)double f(double t) {
double r62422 = 1.0;
double r62423 = t;
double r62424 = 2e-16;
double r62425 = r62423 * r62424;
double r62426 = r62422 + r62425;
double r62427 = r62426 * r62426;
double r62428 = -1.0;
double r62429 = 2.0;
double r62430 = r62429 * r62425;
double r62431 = r62428 - r62430;
double r62432 = r62427 + r62431;
return r62432;
}
double f(double t) {
double r62433 = t;
double r62434 = 3.9999999999999997e-32;
double r62435 = r62434 * r62433;
double r62436 = r62433 * r62435;
return r62436;
}




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 sqr-pow0.3
Applied associate-*r*0.3
Simplified0.3
Final simplification0.3
herbie shell --seed 2019212 +o rules:numerics
(FPCore (t)
:name "fma_test1"
:precision binary64
:pre (<= 0.900000000000000022 t 1.1000000000000001)
: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)))))