Average Error: 0.0 → 0.0
Time: 8.6s
Precision: 64
\[56789 \le a \le 98765 \land 0 \le b \le 1 \land 0 \le c \le 0.0016773 \land 0 \le d \le 0.0016773\]
\[a \cdot \left(\left(b + c\right) + d\right)\]
↓
\[\mathsf{fma}\left(c + b, a, a \cdot d\right)\]
a \cdot \left(\left(b + c\right) + d\right)
↓
\mathsf{fma}\left(c + b, a, a \cdot d\right)
double f(double a, double b, double c, double d) {
        double r1864190 = a;
        double r1864191 = b;
        double r1864192 = c;
        double r1864193 = r1864191 + r1864192;
        double r1864194 = d;
        double r1864195 = r1864193 + r1864194;
        double r1864196 = r1864190 * r1864195;
        return r1864196;
}
↓
double f(double a, double b, double c, double d) {
        double r1864197 = c;
        double r1864198 = b;
        double r1864199 = r1864197 + r1864198;
        double r1864200 = a;
        double r1864201 = d;
        double r1864202 = r1864200 * r1864201;
        double r1864203 = fma(r1864199, r1864200, r1864202);
        return r1864203;
}

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 distribute-rgt-in0.0

    \[\leadsto \color{blue}{\left(b + c\right) \cdot a + d \cdot a}\]
  4. Using strategy rm

  5. Applied fma-def0.0

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

  6. Final simplification0.0

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

Reproduce

herbie shell --seed 2019146 +o rules:numerics
(FPCore (a b c d)
  :name "Expression, p14"
  :pre (and (<= 56789 a 98765) (<= 0 b 1) (<= 0 c 0.0016773) (<= 0 d 0.0016773))

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

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