Average Error: 0.0 → 0
Time: 4.3s
Precision: 64
\[0.0 \le x \le 2\]
\[x + x \cdot x\]
\[\mathsf{fma}\left(x, x, x\right)\]
x + x \cdot x
\mathsf{fma}\left(x, x, x\right)
double f(double x) {
        double r57665 = x;
        double r57666 = r57665 * r57665;
        double r57667 = r57665 + r57666;
        return r57667;
}

double f(double x) {
        double r57668 = x;
        double r57669 = fma(r57668, r57668, r57668);
        return r57669;
}

Error

Bits error versus x

Target

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

Derivation

  1. Initial program 0.0

    \[x + x \cdot x\]
  2. Simplified0

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

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

Reproduce

herbie shell --seed 2019305 +o rules:numerics
(FPCore (x)
  :name "Expression 2, p15"
  :precision binary64
  :pre (<= 0.0 x 2)

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

  (+ x (* x x)))