Average Error: 0.0 → 0.0
Time: 854.0ms
Precision: 64
\[200 \cdot \left(x - y\right)\]
↓
\[\mathsf{fma}\left(200, x, 200 \cdot \left(-y\right)\right)\]
200 \cdot \left(x - y\right)
↓
\mathsf{fma}\left(200, x, 200 \cdot \left(-y\right)\right)
double f(double x, double y) {
        double r209018 = 200.0;
        double r209019 = x;
        double r209020 = y;
        double r209021 = r209019 - r209020;
        double r209022 = r209018 * r209021;
        return r209022;
}
↓
double f(double x, double y) {
        double r209023 = 200.0;
        double r209024 = x;
        double r209025 = y;
        double r209026 = -r209025;
        double r209027 = r209023 * r209026;
        double r209028 = fma(r209023, r209024, r209027);
        return r209028;
}

Error

Bits error versus x

Bits error versus y

Derivation

  1. Initial program 0.0

    \[200 \cdot \left(x - y\right)\]
  2. Using strategy rm

  3. Applied sub-neg0.0

    \[\leadsto 200 \cdot \color{blue}{\left(x + \left(-y\right)\right)}\]

  4. Applied distribute-lft-in0.0

    \[\leadsto \color{blue}{200 \cdot x + 200 \cdot \left(-y\right)}\]
  5. Using strategy rm

  6. Applied fma-def0.0

    \[\leadsto \color{blue}{\mathsf{fma}\left(200, x, 200 \cdot \left(-y\right)\right)}\]

  7. Final simplification0.0

    \[\leadsto \mathsf{fma}\left(200, x, 200 \cdot \left(-y\right)\right)\]

Reproduce

herbie shell --seed 2020062 +o rules:numerics
(FPCore (x y)
  :name "Data.Colour.CIE:cieLABView from colour-2.3.3, C"
  :precision binary64
  (* 200 (- x y)))