code[x_, y_, z_, t_, a_, b_, c_, i_] := N[(x * y + N[(z * t + N[(c * i + N[(a * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\left(\left(x \cdot y + z \cdot t\right) + a \cdot b\right) + c \cdot i
↓
\mathsf{fma}\left(x, y, \mathsf{fma}\left(z, t, \mathsf{fma}\left(c, i, a \cdot b\right)\right)\right)
Error
Derivation
Initial program 0.0
\[\left(\left(x \cdot y + z \cdot t\right) + a \cdot b\right) + c \cdot i
\]
Simplified0.0
\[\leadsto \color{blue}{\mathsf{fma}\left(x, y, \mathsf{fma}\left(z, t, \mathsf{fma}\left(c, i, a \cdot b\right)\right)\right)}
\]
Proof
(fma.f64 x y (fma.f64 z t (fma.f64 c i (*.f64 a b)))): 0 points increase in error, 0 points decrease in error
(fma.f64 x y (fma.f64 z t (Rewrite<= fma-def_binary64 (+.f64 (*.f64 c i) (*.f64 a b))))): 1 points increase in error, 0 points decrease in error
(fma.f64 x y (fma.f64 z t (Rewrite<= +-commutative_binary64 (+.f64 (*.f64 a b) (*.f64 c i))))): 0 points increase in error, 0 points decrease in error
(fma.f64 x y (Rewrite<= fma-def_binary64 (+.f64 (*.f64 z t) (+.f64 (*.f64 a b) (*.f64 c i))))): 1 points increase in error, 0 points decrease in error
(Rewrite<= fma-def_binary64 (+.f64 (*.f64 x y) (+.f64 (*.f64 z t) (+.f64 (*.f64 a b) (*.f64 c i))))): 1 points increase in error, 0 points decrease in error
(Rewrite<= associate-+l+_binary64 (+.f64 (+.f64 (*.f64 x y) (*.f64 z t)) (+.f64 (*.f64 a b) (*.f64 c i)))): 0 points increase in error, 0 points decrease in error
(Rewrite<= associate-+l+_binary64 (+.f64 (+.f64 (+.f64 (*.f64 x y) (*.f64 z t)) (*.f64 a b)) (*.f64 c i))): 0 points increase in error, 0 points decrease in error
Final simplification0.0
\[\leadsto \mathsf{fma}\left(x, y, \mathsf{fma}\left(z, t, \mathsf{fma}\left(c, i, a \cdot b\right)\right)\right)
\]
Alternatives
Alternative 1
Error
0.0
Cost
7232
\[\left(a \cdot b + \mathsf{fma}\left(z, t, x \cdot y\right)\right) + c \cdot i
\]
Alternative 2
Error
23.0
Cost
2528
\[\begin{array}{l}
t_1 := a \cdot b + z \cdot t\\
t_2 := x \cdot y + z \cdot t\\
t_3 := c \cdot i + x \cdot y\\
\mathbf{if}\;c \cdot i \leq -4.697473897752212 \cdot 10^{-19}:\\
\;\;\;\;c \cdot i + z \cdot t\\
\mathbf{elif}\;c \cdot i \leq -3.2401571766324545 \cdot 10^{-141}:\\
\;\;\;\;t_1\\
\mathbf{elif}\;c \cdot i \leq -3.573402175545362 \cdot 10^{-207}:\\
\;\;\;\;t_2\\
\mathbf{elif}\;c \cdot i \leq 2.8320565703961553 \cdot 10^{-245}:\\
\;\;\;\;t_1\\
\mathbf{elif}\;c \cdot i \leq 2.3671736483091406 \cdot 10^{-22}:\\
\;\;\;\;t_2\\
\mathbf{elif}\;c \cdot i \leq 2.5195180782021278 \cdot 10^{+35}:\\
\;\;\;\;t_1\\
\mathbf{elif}\;c \cdot i \leq 1.5632087357188235 \cdot 10^{+89}:\\
\;\;\;\;t_3\\
\mathbf{elif}\;c \cdot i \leq 2.4055591713342117 \cdot 10^{+161}:\\
\;\;\;\;t_1\\
\mathbf{else}:\\
\;\;\;\;t_3\\
\end{array}
\]
Alternative 3
Error
22.2
Cost
2268
\[\begin{array}{l}
t_1 := a \cdot b + z \cdot t\\
t_2 := x \cdot y + z \cdot t\\
\mathbf{if}\;c \cdot i \leq -4.697473897752212 \cdot 10^{-19}:\\
\;\;\;\;c \cdot i + z \cdot t\\
\mathbf{elif}\;c \cdot i \leq -3.2401571766324545 \cdot 10^{-141}:\\
\;\;\;\;t_1\\
\mathbf{elif}\;c \cdot i \leq -3.573402175545362 \cdot 10^{-207}:\\
\;\;\;\;t_2\\
\mathbf{elif}\;c \cdot i \leq 2.8320565703961553 \cdot 10^{-245}:\\
\;\;\;\;t_1\\
\mathbf{elif}\;c \cdot i \leq 2.3671736483091406 \cdot 10^{-22}:\\
\;\;\;\;t_2\\
\mathbf{elif}\;c \cdot i \leq 2.5195180782021278 \cdot 10^{+35}:\\
\;\;\;\;t_1\\
\mathbf{elif}\;c \cdot i \leq 1.5632087357188235 \cdot 10^{+89}:\\
\;\;\;\;c \cdot i + x \cdot y\\
\mathbf{else}:\\
\;\;\;\;a \cdot b + c \cdot i\\
\end{array}
\]
\[\begin{array}{l}
\mathbf{if}\;c \cdot i \leq -3.730310327670248 \cdot 10^{+69}:\\
\;\;\;\;c \cdot i + z \cdot t\\
\mathbf{elif}\;c \cdot i \leq 2.4055591713342117 \cdot 10^{+161}:\\
\;\;\;\;a \cdot b + \left(x \cdot y + z \cdot t\right)\\
\mathbf{else}:\\
\;\;\;\;c \cdot i + x \cdot y\\
\end{array}
\]
Alternative 8
Error
8.0
Cost
1224
\[\begin{array}{l}
t_1 := x \cdot y + z \cdot t\\
\mathbf{if}\;a \cdot b \leq -1.1553018113381797 \cdot 10^{+112}:\\
\;\;\;\;a \cdot b + t_1\\
\mathbf{elif}\;a \cdot b \leq 1.1582583005635591 \cdot 10^{+55}:\\
\;\;\;\;c \cdot i + t_1\\
\mathbf{else}:\\
\;\;\;\;a \cdot b + c \cdot i\\
\end{array}
\]
Alternative 9
Error
25.0
Cost
968
\[\begin{array}{l}
\mathbf{if}\;c \cdot i \leq -5.3576405773166224 \cdot 10^{+88}:\\
\;\;\;\;c \cdot i\\
\mathbf{elif}\;c \cdot i \leq 2.4055591713342117 \cdot 10^{+161}:\\
\;\;\;\;a \cdot b + z \cdot t\\
\mathbf{else}:\\
\;\;\;\;c \cdot i\\
\end{array}
\]
Alternative 10
Error
23.0
Cost
968
\[\begin{array}{l}
t_1 := c \cdot i + z \cdot t\\
\mathbf{if}\;c \cdot i \leq -4.697473897752212 \cdot 10^{-19}:\\
\;\;\;\;t_1\\
\mathbf{elif}\;c \cdot i \leq 1.544313631646826 \cdot 10^{+127}:\\
\;\;\;\;a \cdot b + z \cdot t\\
\mathbf{else}:\\
\;\;\;\;t_1\\
\end{array}
\]
Alternative 11
Error
0.0
Cost
960
\[c \cdot i + \left(a \cdot b + \left(x \cdot y + z \cdot t\right)\right)
\]
herbie shell --seed 2022297
(FPCore (x y z t a b c i)
:name "Linear.V4:$cdot from linear-1.19.1.3, C"
:precision binary64
(+ (+ (+ (* x y) (* z t)) (* a b)) (* c i)))