\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)\sqrt{3.999999999999999676487027278085939408227 \cdot 10^{-32}} \cdot \left(\sqrt{\sqrt{3.999999999999999676487027278085939408227 \cdot 10^{-32}}} \cdot \left(t \cdot \left(\sqrt{\sqrt{3.999999999999999676487027278085939408227 \cdot 10^{-32}}} \cdot t\right)\right)\right)double f(double t) {
double r62043 = 1.0;
double r62044 = t;
double r62045 = 2e-16;
double r62046 = r62044 * r62045;
double r62047 = r62043 + r62046;
double r62048 = r62047 * r62047;
double r62049 = -1.0;
double r62050 = 2.0;
double r62051 = r62050 * r62046;
double r62052 = r62049 - r62051;
double r62053 = r62048 + r62052;
return r62053;
}
double f(double t) {
double r62054 = 3.9999999999999997e-32;
double r62055 = sqrt(r62054);
double r62056 = sqrt(r62055);
double r62057 = t;
double r62058 = r62056 * r62057;
double r62059 = r62057 * r62058;
double r62060 = r62056 * r62059;
double r62061 = r62055 * r62060;
return r62061;
}




Bits error versus t
Results
| Original | 61.8 |
|---|---|
| Target | 50.6 |
| Herbie | 0.4 |
Initial program 61.8
Taylor expanded around 0 0.3
rmApplied add-sqr-sqrt0.3
Applied associate-*l*0.4
rmApplied add-sqr-sqrt0.4
Applied sqrt-prod0.4
Applied associate-*l*0.4
Simplified0.4
Final simplification0.4
herbie shell --seed 2019323
(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)))))