Average Error: 0.0 → 0.0
Time: 8.8s
Precision: 64
\[0 \le x \le 2\]
\[x \cdot \left(x \cdot x\right) + x \cdot x\]
\[\mathsf{fma}\left(x \cdot x, x, x \cdot x\right)\]
x \cdot \left(x \cdot x\right) + x \cdot x
\mathsf{fma}\left(x \cdot x, x, x \cdot x\right)
double f(double x) {
        double r1589790 = x;
        double r1589791 = r1589790 * r1589790;
        double r1589792 = r1589790 * r1589791;
        double r1589793 = r1589792 + r1589791;
        return r1589793;
}

double f(double x) {
        double r1589794 = x;
        double r1589795 = r1589794 * r1589794;
        double r1589796 = fma(r1589795, r1589794, r1589795);
        return r1589796;
}

Error

Bits error versus x

Target

Original0.0
Target0.0
Herbie0.0
\[\left(\left(1.0 + x\right) \cdot x\right) \cdot x\]

Derivation

  1. Initial program 0.0

    \[x \cdot \left(x \cdot x\right) + x \cdot x\]
  2. Simplified0.0

    \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot x, x, x \cdot x\right)}\]
  3. Final simplification0.0

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

Reproduce

herbie shell --seed 2019153 +o rules:numerics
(FPCore (x)
  :name "Expression 3, p15"
  :pre (<= 0 x 2)

  :herbie-target
  (* (* (+ 1.0 x) x) x)

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