Average Error: 45.0 → 8.0
Time: 14.0s
Precision: 64
Internal Precision: 128
\[(x \cdot y + z)_* - \left(1 + \left(x \cdot y + z\right)\right)\]
\[\left((x \cdot y + z)_* - \left(z + x \cdot y\right)\right) - 1\]

Error

Bits error versus x

Bits error versus y

Bits error versus z

Target

Original45.0
Target0
Herbie8.0
\[-1\]

Derivation

  1. Initial program 45.0

    \[(x \cdot y + z)_* - \left(1 + \left(x \cdot y + z\right)\right)\]
  2. Initial simplification34.6

    \[\leadsto \left((x \cdot y + z)_* - x \cdot y\right) - \left(z - -1\right)\]
  3. Using strategy rm
  4. Applied sub-neg34.6

    \[\leadsto \left((x \cdot y + z)_* - x \cdot y\right) - \color{blue}{\left(z + \left(--1\right)\right)}\]
  5. Applied associate--r+13.4

    \[\leadsto \color{blue}{\left(\left((x \cdot y + z)_* - x \cdot y\right) - z\right) - \left(--1\right)}\]
  6. Simplified13.4

    \[\leadsto \left(\left((x \cdot y + z)_* - x \cdot y\right) - z\right) - \color{blue}{1}\]
  7. Using strategy rm
  8. Applied add-cube-cbrt31.4

    \[\leadsto \left(\color{blue}{\left(\sqrt[3]{(x \cdot y + z)_* - x \cdot y} \cdot \sqrt[3]{(x \cdot y + z)_* - x \cdot y}\right) \cdot \sqrt[3]{(x \cdot y + z)_* - x \cdot y}} - z\right) - 1\]
  9. Taylor expanded around 0 8.0

    \[\leadsto \color{blue}{\left((x \cdot y + z)_* - \left(z + x \cdot y\right)\right)} - 1\]
  10. Final simplification8.0

    \[\leadsto \left((x \cdot y + z)_* - \left(z + x \cdot y\right)\right) - 1\]

Runtime

Time bar (total: 14.0s)Debug logProfile

BaselineHerbieOracleSpan%
Regimes8.08.07.90.10%
herbie shell --seed 2018354 
(FPCore (x y z)
  :name "simple fma test"

  :herbie-target
  -1

  (- (fma x y z) (+ 1 (+ (* x y) z))))