\left(a + \left(b + \left(c + d\right)\right)\right) \cdot 2
\left(a + \left(\left(b + c\right) + d\right)\right) \cdot 2
double f(double a, double b, double c, double d) {
double r99219 = a;
double r99220 = b;
double r99221 = c;
double r99222 = d;
double r99223 = r99221 + r99222;
double r99224 = r99220 + r99223;
double r99225 = r99219 + r99224;
double r99226 = 2.0;
double r99227 = r99225 * r99226;
return r99227;
}
double f(double a, double b, double c, double d) {
double r99228 = a;
double r99229 = b;
double r99230 = c;
double r99231 = r99229 + r99230;
double r99232 = d;
double r99233 = r99231 + r99232;
double r99234 = r99228 + r99233;
double r99235 = 2.0;
double r99236 = r99234 * r99235;
return r99236;
}




Bits error versus a




Bits error versus b




Bits error versus c




Bits error versus d
Results
| Original | 3.7 |
|---|---|
| Target | 3.8 |
| Herbie | 2.8 |
Initial program 3.7
rmApplied associate-+r+2.8
rmApplied add-cbrt-cube2.9
Simplified2.9
rmApplied rem-cbrt-cube2.8
Final simplification2.8
herbie shell --seed 2019304 +o rules:numerics
(FPCore (a b c d)
:name "Expression, p6"
:precision binary64
:pre (and (<= -14 a -13) (<= -3 b -2) (<= 3 c 3.5) (<= 12.5 d 13.5))
:herbie-target
(+ (* (+ a b) 2) (* (+ c d) 2))
(* (+ a (+ b (+ c d))) 2))