\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(\left(\sqrt{3.999999999999999676487027278085939408227 \cdot 10^{-32}} \cdot \left|t\right|\right) \cdot \sqrt{{t}^{2}}\right)double f(double t) {
double r80385 = 1.0;
double r80386 = t;
double r80387 = 2e-16;
double r80388 = r80386 * r80387;
double r80389 = r80385 + r80388;
double r80390 = r80389 * r80389;
double r80391 = -1.0;
double r80392 = 2.0;
double r80393 = r80392 * r80388;
double r80394 = r80391 - r80393;
double r80395 = r80390 + r80394;
return r80395;
}
double f(double t) {
double r80396 = 3.9999999999999997e-32;
double r80397 = sqrt(r80396);
double r80398 = t;
double r80399 = fabs(r80398);
double r80400 = r80397 * r80399;
double r80401 = 2.0;
double r80402 = pow(r80398, r80401);
double r80403 = sqrt(r80402);
double r80404 = r80400 * r80403;
double r80405 = r80397 * r80404;
return r80405;
}




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-*l*0.4
rmApplied add-sqr-sqrt0.4
Applied associate-*r*0.3
Simplified0.3
Final simplification0.3
herbie shell --seed 2019350 +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)))))