Average Error: 0.0 → 0.0
Time: 1.2s
Precision: 64
\[56789 \le a \le 98765 \land 0.0 \le b \le 1 \land 0.0 \le c \le 0.0016773000000000001 \land 0.0 \le d \le 0.0016773000000000001\]
\[a \cdot \left(\left(b + c\right) + d\right)\]
↓
\[\mathsf{fma}\left(d, a, \mathsf{fma}\left(a, b, a \cdot c\right)\right)\]
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 r102583 = a;
        double r102584 = b;
        double r102585 = c;
        double r102586 = r102584 + r102585;
        double r102587 = d;
        double r102588 = r102586 + r102587;
        double r102589 = r102583 * r102588;
        return r102589;
}
↓
double f(double a, double b, double c, double d) {
        double r102590 = d;
        double r102591 = a;
        double r102592 = b;
        double r102593 = c;
        double r102594 = r102591 * r102593;
        double r102595 = fma(r102591, r102592, r102594);
        double r102596 = fma(r102590, r102591, r102595);
        return r102596;
}

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 *-un-lft-identity0.0

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

  4. Applied associate-*l*0.0

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

  5. Simplified0.0

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

  6. Final simplification0.0

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

Reproduce

herbie shell --seed 2020064 +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)))