Average Error: 0.0 → 0.0
Time: 510.0ms
Precision: 64
\[0.0 \le x \le 2\]
\[x \cdot \left(x \cdot x\right) + x \cdot x\]
↓
\[\mathsf{fma}\left(x, x, {x}^{3}\right)\]
x \cdot \left(x \cdot x\right) + x \cdot x
↓
\mathsf{fma}\left(x, x, {x}^{3}\right)
double f(double x) {
        double r93720 = x;
        double r93721 = r93720 * r93720;
        double r93722 = r93720 * r93721;
        double r93723 = r93722 + r93721;
        return r93723;
}
↓
double f(double x) {
        double r93724 = x;
        double r93725 = 3.0;
        double r93726 = pow(r93724, r93725);
        double r93727 = fma(r93724, r93724, r93726);
        return r93727;
}

Error

Bits error versus x

Target

Original0.0
Target0.0
Herbie0.0
\[\left(\left(1 + x\right) \cdot x\right) \cdot x\]

Derivation

  1. Initial program 0.0

    \[x \cdot \left(x \cdot x\right) + x \cdot x\]

  2. Simplified0.0

    \[\leadsto \color{blue}{\mathsf{fma}\left(x, x, {x}^{3}\right)}\]

  3. Final simplification0.0

    \[\leadsto \mathsf{fma}\left(x, x, {x}^{3}\right)\]

Reproduce

herbie shell --seed 2020020 +o rules:numerics
(FPCore (x)
  :name "Expression 3, p15"
  :precision binary64
  :pre (<= 0.0 x 2)

  :herbie-target
  (* (* (+ 1 x) x) x)

  (+ (* x (* x x)) (* x x)))