Average Error: 0.0 → 0.0
Time: 1.9s
Precision: 64
\[56789 \le a \le 98765 \land 0.0 \le b \le 1 \land 0.0 \le c \le 0.001677300000000000058247850986958837893326 \land 0.0 \le d \le 0.001677300000000000058247850986958837893326\]
\[a \cdot \left(\left(b + c\right) + d\right)\]
↓
\[\mathsf{fma}\left(d, a, \mathsf{fma}\left(a, b, a \cdot c\right)\right)\]
a \cdot \left(\left(b + c\right) + d\right)
↓
\mathsf{fma}\left(d, a, \mathsf{fma}\left(a, b, a \cdot c\right)\right)
double f(double a, double b, double c, double d) {
        double r86173 = a;
        double r86174 = b;
        double r86175 = c;
        double r86176 = r86174 + r86175;
        double r86177 = d;
        double r86178 = r86176 + r86177;
        double r86179 = r86173 * r86178;
        return r86179;
}
↓
double f(double a, double b, double c, double d) {
        double r86180 = d;
        double r86181 = a;
        double r86182 = b;
        double r86183 = c;
        double r86184 = r86181 * r86183;
        double r86185 = fma(r86181, r86182, r86184);
        double r86186 = fma(r86180, r86181, r86185);
        return r86186;
}

Error

Bits error versus a

Bits error versus b

Bits error versus c

Bits error versus d

Target

Original0.0
Target0.0
Herbie0.0
\[a \cdot b + a \cdot \left(c + d\right)\]

Derivation

  1. Initial program 0.0

    \[a \cdot \left(\left(b + c\right) + d\right)\]
  2. Using strategy rm

  3. Applied pow10.0

    \[\leadsto a \cdot \color{blue}{{\left(\left(b + c\right) + d\right)}^{1}}\]

  4. Applied pow10.0

    \[\leadsto \color{blue}{{a}^{1}} \cdot {\left(\left(b + c\right) + d\right)}^{1}\]

  5. Applied pow-prod-down0.0

    \[\leadsto \color{blue}{{\left(a \cdot \left(\left(b + c\right) + d\right)\right)}^{1}}\]

  6. Simplified0.0

    \[\leadsto {\color{blue}{\left(\mathsf{fma}\left(d, a, \mathsf{fma}\left(a, b, a \cdot c\right)\right)\right)}}^{1}\]

  7. Final simplification0.0

    \[\leadsto \mathsf{fma}\left(d, a, \mathsf{fma}\left(a, b, a \cdot c\right)\right)\]

Reproduce

herbie shell --seed 2019362 +o rules:numerics
(FPCore (a b c d)
  :name "Expression, p14"
  :precision binary64
  :pre (and (<= 56789 a 98765) (<= 0.0 b 1) (<= 0.0 c 0.0016773) (<= 0.0 d 0.0016773))

  :herbie-target
  (+ (* a b) (* a (+ c d)))

  (* a (+ (+ b c) d)))