Average Error: 0.0 → 0.0
Time: 512.0ms
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 r79772 = x;
        double r79773 = r79772 * r79772;
        double r79774 = r79772 * r79773;
        double r79775 = r79774 + r79773;
        return r79775;
}
↓
double f(double x) {
        double r79776 = x;
        double r79777 = 3.0;
        double r79778 = pow(r79776, r79777);
        double r79779 = fma(r79776, r79776, r79778);
        return r79779;
}

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 2020002 +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)))