fabs fraction 1

Percentage Accurate: 91.5% → 99.5%
Time: 7.9s
Alternatives: 9
Speedup: 1.6×

Specification

?
\[\begin{array}{l} \\ \left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right| \end{array} \]
(FPCore (x y z) :precision binary64 (fabs (- (/ (+ x 4.0) y) (* (/ x y) z))))
double code(double x, double y, double z) {
	return fabs((((x + 4.0) / y) - ((x / y) * z)));
}
real(8) function code(x, y, z)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    code = abs((((x + 4.0d0) / y) - ((x / y) * z)))
end function
public static double code(double x, double y, double z) {
	return Math.abs((((x + 4.0) / y) - ((x / y) * z)));
}
def code(x, y, z):
	return math.fabs((((x + 4.0) / y) - ((x / y) * z)))
function code(x, y, z)
	return abs(Float64(Float64(Float64(x + 4.0) / y) - Float64(Float64(x / y) * z)))
end
function tmp = code(x, y, z)
	tmp = abs((((x + 4.0) / y) - ((x / y) * z)));
end
code[x_, y_, z_] := N[Abs[N[(N[(N[(x + 4.0), $MachinePrecision] / y), $MachinePrecision] - N[(N[(x / y), $MachinePrecision] * z), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}

\\
\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right|
\end{array}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 9 alternatives:

AlternativeAccuracySpeedup
The accuracy (vertical axis) and speed (horizontal axis) of each alternatives. Up and to the right is better. The red square shows the initial program, and each blue circle shows an alternative.The line shows the best available speed-accuracy tradeoffs.

Initial Program: 91.5% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right| \end{array} \]
(FPCore (x y z) :precision binary64 (fabs (- (/ (+ x 4.0) y) (* (/ x y) z))))
double code(double x, double y, double z) {
	return fabs((((x + 4.0) / y) - ((x / y) * z)));
}
real(8) function code(x, y, z)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    code = abs((((x + 4.0d0) / y) - ((x / y) * z)))
end function
public static double code(double x, double y, double z) {
	return Math.abs((((x + 4.0) / y) - ((x / y) * z)));
}
def code(x, y, z):
	return math.fabs((((x + 4.0) / y) - ((x / y) * z)))
function code(x, y, z)
	return abs(Float64(Float64(Float64(x + 4.0) / y) - Float64(Float64(x / y) * z)))
end
function tmp = code(x, y, z)
	tmp = abs((((x + 4.0) / y) - ((x / y) * z)));
end
code[x_, y_, z_] := N[Abs[N[(N[(N[(x + 4.0), $MachinePrecision] / y), $MachinePrecision] - N[(N[(x / y), $MachinePrecision] * z), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}

\\
\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right|
\end{array}

Alternative 1: 99.5% accurate, 0.9× speedup?

\[\begin{array}{l} y_m = \left|y\right| \\ \begin{array}{l} \mathbf{if}\;y\_m \leq 6.8 \cdot 10^{-86}:\\ \;\;\;\;\left|\frac{\mathsf{fma}\left(x, z, -4 - x\right)}{y\_m}\right|\\ \mathbf{else}:\\ \;\;\;\;\left|\mathsf{fma}\left(-x, \frac{z}{y\_m}, \frac{x + 4}{y\_m}\right)\right|\\ \end{array} \end{array} \]
y_m = (fabs.f64 y)
(FPCore (x y_m z)
 :precision binary64
 (if (<= y_m 6.8e-86)
   (fabs (/ (fma x z (- -4.0 x)) y_m))
   (fabs (fma (- x) (/ z y_m) (/ (+ x 4.0) y_m)))))
y_m = fabs(y);
double code(double x, double y_m, double z) {
	double tmp;
	if (y_m <= 6.8e-86) {
		tmp = fabs((fma(x, z, (-4.0 - x)) / y_m));
	} else {
		tmp = fabs(fma(-x, (z / y_m), ((x + 4.0) / y_m)));
	}
	return tmp;
}
y_m = abs(y)
function code(x, y_m, z)
	tmp = 0.0
	if (y_m <= 6.8e-86)
		tmp = abs(Float64(fma(x, z, Float64(-4.0 - x)) / y_m));
	else
		tmp = abs(fma(Float64(-x), Float64(z / y_m), Float64(Float64(x + 4.0) / y_m)));
	end
	return tmp
end
y_m = N[Abs[y], $MachinePrecision]
code[x_, y$95$m_, z_] := If[LessEqual[y$95$m, 6.8e-86], N[Abs[N[(N[(x * z + N[(-4.0 - x), $MachinePrecision]), $MachinePrecision] / y$95$m), $MachinePrecision]], $MachinePrecision], N[Abs[N[((-x) * N[(z / y$95$m), $MachinePrecision] + N[(N[(x + 4.0), $MachinePrecision] / y$95$m), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]
\begin{array}{l}
y_m = \left|y\right|

\\
\begin{array}{l}
\mathbf{if}\;y\_m \leq 6.8 \cdot 10^{-86}:\\
\;\;\;\;\left|\frac{\mathsf{fma}\left(x, z, -4 - x\right)}{y\_m}\right|\\

\mathbf{else}:\\
\;\;\;\;\left|\mathsf{fma}\left(-x, \frac{z}{y\_m}, \frac{x + 4}{y\_m}\right)\right|\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < 6.8000000000000001e-86

    1. Initial program 87.8%

      \[\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right| \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. lift-fabs.f64N/A

        \[\leadsto \color{blue}{\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right|} \]
      2. neg-fabsN/A

        \[\leadsto \color{blue}{\left|\mathsf{neg}\left(\left(\frac{x + 4}{y} - \frac{x}{y} \cdot z\right)\right)\right|} \]
      3. lower-fabs.f64N/A

        \[\leadsto \color{blue}{\left|\mathsf{neg}\left(\left(\frac{x + 4}{y} - \frac{x}{y} \cdot z\right)\right)\right|} \]
      4. lift--.f64N/A

        \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\frac{x + 4}{y} - \frac{x}{y} \cdot z\right)}\right)\right| \]
      5. sub-negN/A

        \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\frac{x + 4}{y} + \left(\mathsf{neg}\left(\frac{x}{y} \cdot z\right)\right)\right)}\right)\right| \]
      6. +-commutativeN/A

        \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\left(\mathsf{neg}\left(\frac{x}{y} \cdot z\right)\right) + \frac{x + 4}{y}\right)}\right)\right| \]
      7. distribute-neg-inN/A

        \[\leadsto \left|\color{blue}{\left(\mathsf{neg}\left(\left(\mathsf{neg}\left(\frac{x}{y} \cdot z\right)\right)\right)\right) + \left(\mathsf{neg}\left(\frac{x + 4}{y}\right)\right)}\right| \]
      8. remove-double-negN/A

        \[\leadsto \left|\color{blue}{\frac{x}{y} \cdot z} + \left(\mathsf{neg}\left(\frac{x + 4}{y}\right)\right)\right| \]
      9. sub-negN/A

        \[\leadsto \left|\color{blue}{\frac{x}{y} \cdot z - \frac{x + 4}{y}}\right| \]
      10. lift-*.f64N/A

        \[\leadsto \left|\color{blue}{\frac{x}{y} \cdot z} - \frac{x + 4}{y}\right| \]
      11. lift-/.f64N/A

        \[\leadsto \left|\color{blue}{\frac{x}{y}} \cdot z - \frac{x + 4}{y}\right| \]
      12. associate-*l/N/A

        \[\leadsto \left|\color{blue}{\frac{x \cdot z}{y}} - \frac{x + 4}{y}\right| \]
      13. lift-/.f64N/A

        \[\leadsto \left|\frac{x \cdot z}{y} - \color{blue}{\frac{x + 4}{y}}\right| \]
      14. sub-divN/A

        \[\leadsto \left|\color{blue}{\frac{x \cdot z - \left(x + 4\right)}{y}}\right| \]
      15. lower-/.f64N/A

        \[\leadsto \left|\color{blue}{\frac{x \cdot z - \left(x + 4\right)}{y}}\right| \]
      16. sub-negN/A

        \[\leadsto \left|\frac{\color{blue}{x \cdot z + \left(\mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
      17. lower-fma.f64N/A

        \[\leadsto \left|\frac{\color{blue}{\mathsf{fma}\left(x, z, \mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
      18. lift-+.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \mathsf{neg}\left(\color{blue}{\left(x + 4\right)}\right)\right)}{y}\right| \]
      19. +-commutativeN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \mathsf{neg}\left(\color{blue}{\left(4 + x\right)}\right)\right)}{y}\right| \]
      20. distribute-neg-inN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) + \left(\mathsf{neg}\left(x\right)\right)}\right)}{y}\right| \]
      21. unsub-negN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      22. lower--.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      23. metadata-eval98.2

        \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{-4} - x\right)}{y}\right| \]
    4. Applied rewrites98.2%

      \[\leadsto \color{blue}{\left|\frac{\mathsf{fma}\left(x, z, -4 - x\right)}{y}\right|} \]

    if 6.8000000000000001e-86 < y

    1. Initial program 94.3%

      \[\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right| \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. lift--.f64N/A

        \[\leadsto \left|\color{blue}{\frac{x + 4}{y} - \frac{x}{y} \cdot z}\right| \]
      2. sub-negN/A

        \[\leadsto \left|\color{blue}{\frac{x + 4}{y} + \left(\mathsf{neg}\left(\frac{x}{y} \cdot z\right)\right)}\right| \]
      3. +-commutativeN/A

        \[\leadsto \left|\color{blue}{\left(\mathsf{neg}\left(\frac{x}{y} \cdot z\right)\right) + \frac{x + 4}{y}}\right| \]
      4. lift-*.f64N/A

        \[\leadsto \left|\left(\mathsf{neg}\left(\color{blue}{\frac{x}{y} \cdot z}\right)\right) + \frac{x + 4}{y}\right| \]
      5. lift-/.f64N/A

        \[\leadsto \left|\left(\mathsf{neg}\left(\color{blue}{\frac{x}{y}} \cdot z\right)\right) + \frac{x + 4}{y}\right| \]
      6. associate-*l/N/A

        \[\leadsto \left|\left(\mathsf{neg}\left(\color{blue}{\frac{x \cdot z}{y}}\right)\right) + \frac{x + 4}{y}\right| \]
      7. associate-/l*N/A

        \[\leadsto \left|\left(\mathsf{neg}\left(\color{blue}{x \cdot \frac{z}{y}}\right)\right) + \frac{x + 4}{y}\right| \]
      8. distribute-lft-neg-inN/A

        \[\leadsto \left|\color{blue}{\left(\mathsf{neg}\left(x\right)\right) \cdot \frac{z}{y}} + \frac{x + 4}{y}\right| \]
      9. lower-fma.f64N/A

        \[\leadsto \left|\color{blue}{\mathsf{fma}\left(\mathsf{neg}\left(x\right), \frac{z}{y}, \frac{x + 4}{y}\right)}\right| \]
      10. lower-neg.f64N/A

        \[\leadsto \left|\mathsf{fma}\left(\color{blue}{\mathsf{neg}\left(x\right)}, \frac{z}{y}, \frac{x + 4}{y}\right)\right| \]
      11. lower-/.f64100.0

        \[\leadsto \left|\mathsf{fma}\left(-x, \color{blue}{\frac{z}{y}}, \frac{x + 4}{y}\right)\right| \]
    4. Applied rewrites100.0%

      \[\leadsto \left|\color{blue}{\mathsf{fma}\left(-x, \frac{z}{y}, \frac{x + 4}{y}\right)}\right| \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 2: 94.1% accurate, 1.1× speedup?

\[\begin{array}{l} y_m = \left|y\right| \\ \begin{array}{l} \mathbf{if}\;x \leq -1860000000000:\\ \;\;\;\;\left|\frac{\mathsf{fma}\left(x, z, -x\right)}{y\_m}\right|\\ \mathbf{elif}\;x \leq 5.6 \cdot 10^{-14}:\\ \;\;\;\;\left|\frac{\mathsf{fma}\left(x, z, -4\right)}{y\_m}\right|\\ \mathbf{else}:\\ \;\;\;\;\left|\frac{x - x \cdot z}{y\_m}\right|\\ \end{array} \end{array} \]
y_m = (fabs.f64 y)
(FPCore (x y_m z)
 :precision binary64
 (if (<= x -1860000000000.0)
   (fabs (/ (fma x z (- x)) y_m))
   (if (<= x 5.6e-14)
     (fabs (/ (fma x z -4.0) y_m))
     (fabs (/ (- x (* x z)) y_m)))))
y_m = fabs(y);
double code(double x, double y_m, double z) {
	double tmp;
	if (x <= -1860000000000.0) {
		tmp = fabs((fma(x, z, -x) / y_m));
	} else if (x <= 5.6e-14) {
		tmp = fabs((fma(x, z, -4.0) / y_m));
	} else {
		tmp = fabs(((x - (x * z)) / y_m));
	}
	return tmp;
}
y_m = abs(y)
function code(x, y_m, z)
	tmp = 0.0
	if (x <= -1860000000000.0)
		tmp = abs(Float64(fma(x, z, Float64(-x)) / y_m));
	elseif (x <= 5.6e-14)
		tmp = abs(Float64(fma(x, z, -4.0) / y_m));
	else
		tmp = abs(Float64(Float64(x - Float64(x * z)) / y_m));
	end
	return tmp
end
y_m = N[Abs[y], $MachinePrecision]
code[x_, y$95$m_, z_] := If[LessEqual[x, -1860000000000.0], N[Abs[N[(N[(x * z + (-x)), $MachinePrecision] / y$95$m), $MachinePrecision]], $MachinePrecision], If[LessEqual[x, 5.6e-14], N[Abs[N[(N[(x * z + -4.0), $MachinePrecision] / y$95$m), $MachinePrecision]], $MachinePrecision], N[Abs[N[(N[(x - N[(x * z), $MachinePrecision]), $MachinePrecision] / y$95$m), $MachinePrecision]], $MachinePrecision]]]
\begin{array}{l}
y_m = \left|y\right|

\\
\begin{array}{l}
\mathbf{if}\;x \leq -1860000000000:\\
\;\;\;\;\left|\frac{\mathsf{fma}\left(x, z, -x\right)}{y\_m}\right|\\

\mathbf{elif}\;x \leq 5.6 \cdot 10^{-14}:\\
\;\;\;\;\left|\frac{\mathsf{fma}\left(x, z, -4\right)}{y\_m}\right|\\

\mathbf{else}:\\
\;\;\;\;\left|\frac{x - x \cdot z}{y\_m}\right|\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if x < -1.86e12

    1. Initial program 87.0%

      \[\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right| \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. lift-fabs.f64N/A

        \[\leadsto \color{blue}{\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right|} \]
      2. neg-fabsN/A

        \[\leadsto \color{blue}{\left|\mathsf{neg}\left(\left(\frac{x + 4}{y} - \frac{x}{y} \cdot z\right)\right)\right|} \]
      3. lower-fabs.f64N/A

        \[\leadsto \color{blue}{\left|\mathsf{neg}\left(\left(\frac{x + 4}{y} - \frac{x}{y} \cdot z\right)\right)\right|} \]
      4. lift--.f64N/A

        \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\frac{x + 4}{y} - \frac{x}{y} \cdot z\right)}\right)\right| \]
      5. sub-negN/A

        \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\frac{x + 4}{y} + \left(\mathsf{neg}\left(\frac{x}{y} \cdot z\right)\right)\right)}\right)\right| \]
      6. +-commutativeN/A

        \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\left(\mathsf{neg}\left(\frac{x}{y} \cdot z\right)\right) + \frac{x + 4}{y}\right)}\right)\right| \]
      7. distribute-neg-inN/A

        \[\leadsto \left|\color{blue}{\left(\mathsf{neg}\left(\left(\mathsf{neg}\left(\frac{x}{y} \cdot z\right)\right)\right)\right) + \left(\mathsf{neg}\left(\frac{x + 4}{y}\right)\right)}\right| \]
      8. remove-double-negN/A

        \[\leadsto \left|\color{blue}{\frac{x}{y} \cdot z} + \left(\mathsf{neg}\left(\frac{x + 4}{y}\right)\right)\right| \]
      9. sub-negN/A

        \[\leadsto \left|\color{blue}{\frac{x}{y} \cdot z - \frac{x + 4}{y}}\right| \]
      10. lift-*.f64N/A

        \[\leadsto \left|\color{blue}{\frac{x}{y} \cdot z} - \frac{x + 4}{y}\right| \]
      11. lift-/.f64N/A

        \[\leadsto \left|\color{blue}{\frac{x}{y}} \cdot z - \frac{x + 4}{y}\right| \]
      12. associate-*l/N/A

        \[\leadsto \left|\color{blue}{\frac{x \cdot z}{y}} - \frac{x + 4}{y}\right| \]
      13. lift-/.f64N/A

        \[\leadsto \left|\frac{x \cdot z}{y} - \color{blue}{\frac{x + 4}{y}}\right| \]
      14. sub-divN/A

        \[\leadsto \left|\color{blue}{\frac{x \cdot z - \left(x + 4\right)}{y}}\right| \]
      15. lower-/.f64N/A

        \[\leadsto \left|\color{blue}{\frac{x \cdot z - \left(x + 4\right)}{y}}\right| \]
      16. sub-negN/A

        \[\leadsto \left|\frac{\color{blue}{x \cdot z + \left(\mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
      17. lower-fma.f64N/A

        \[\leadsto \left|\frac{\color{blue}{\mathsf{fma}\left(x, z, \mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
      18. lift-+.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \mathsf{neg}\left(\color{blue}{\left(x + 4\right)}\right)\right)}{y}\right| \]
      19. +-commutativeN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \mathsf{neg}\left(\color{blue}{\left(4 + x\right)}\right)\right)}{y}\right| \]
      20. distribute-neg-inN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) + \left(\mathsf{neg}\left(x\right)\right)}\right)}{y}\right| \]
      21. unsub-negN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      22. lower--.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      23. metadata-eval94.7

        \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{-4} - x\right)}{y}\right| \]
    4. Applied rewrites94.7%

      \[\leadsto \color{blue}{\left|\frac{\mathsf{fma}\left(x, z, -4 - x\right)}{y}\right|} \]
    5. Taylor expanded in x around inf

      \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{-1 \cdot x}\right)}{y}\right| \]
    6. Step-by-step derivation
      1. mul-1-negN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{\mathsf{neg}\left(x\right)}\right)}{y}\right| \]
      2. lower-neg.f6494.7

        \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{-x}\right)}{y}\right| \]
    7. Applied rewrites94.7%

      \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{-x}\right)}{y}\right| \]

    if -1.86e12 < x < 5.6000000000000001e-14

    1. Initial program 95.1%

      \[\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right| \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. lift-fabs.f64N/A

        \[\leadsto \color{blue}{\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right|} \]
      2. neg-fabsN/A

        \[\leadsto \color{blue}{\left|\mathsf{neg}\left(\left(\frac{x + 4}{y} - \frac{x}{y} \cdot z\right)\right)\right|} \]
      3. lower-fabs.f64N/A

        \[\leadsto \color{blue}{\left|\mathsf{neg}\left(\left(\frac{x + 4}{y} - \frac{x}{y} \cdot z\right)\right)\right|} \]
      4. lift--.f64N/A

        \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\frac{x + 4}{y} - \frac{x}{y} \cdot z\right)}\right)\right| \]
      5. sub-negN/A

        \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\frac{x + 4}{y} + \left(\mathsf{neg}\left(\frac{x}{y} \cdot z\right)\right)\right)}\right)\right| \]
      6. +-commutativeN/A

        \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\left(\mathsf{neg}\left(\frac{x}{y} \cdot z\right)\right) + \frac{x + 4}{y}\right)}\right)\right| \]
      7. distribute-neg-inN/A

        \[\leadsto \left|\color{blue}{\left(\mathsf{neg}\left(\left(\mathsf{neg}\left(\frac{x}{y} \cdot z\right)\right)\right)\right) + \left(\mathsf{neg}\left(\frac{x + 4}{y}\right)\right)}\right| \]
      8. remove-double-negN/A

        \[\leadsto \left|\color{blue}{\frac{x}{y} \cdot z} + \left(\mathsf{neg}\left(\frac{x + 4}{y}\right)\right)\right| \]
      9. sub-negN/A

        \[\leadsto \left|\color{blue}{\frac{x}{y} \cdot z - \frac{x + 4}{y}}\right| \]
      10. lift-*.f64N/A

        \[\leadsto \left|\color{blue}{\frac{x}{y} \cdot z} - \frac{x + 4}{y}\right| \]
      11. lift-/.f64N/A

        \[\leadsto \left|\color{blue}{\frac{x}{y}} \cdot z - \frac{x + 4}{y}\right| \]
      12. associate-*l/N/A

        \[\leadsto \left|\color{blue}{\frac{x \cdot z}{y}} - \frac{x + 4}{y}\right| \]
      13. lift-/.f64N/A

        \[\leadsto \left|\frac{x \cdot z}{y} - \color{blue}{\frac{x + 4}{y}}\right| \]
      14. sub-divN/A

        \[\leadsto \left|\color{blue}{\frac{x \cdot z - \left(x + 4\right)}{y}}\right| \]
      15. lower-/.f64N/A

        \[\leadsto \left|\color{blue}{\frac{x \cdot z - \left(x + 4\right)}{y}}\right| \]
      16. sub-negN/A

        \[\leadsto \left|\frac{\color{blue}{x \cdot z + \left(\mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
      17. lower-fma.f64N/A

        \[\leadsto \left|\frac{\color{blue}{\mathsf{fma}\left(x, z, \mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
      18. lift-+.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \mathsf{neg}\left(\color{blue}{\left(x + 4\right)}\right)\right)}{y}\right| \]
      19. +-commutativeN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \mathsf{neg}\left(\color{blue}{\left(4 + x\right)}\right)\right)}{y}\right| \]
      20. distribute-neg-inN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) + \left(\mathsf{neg}\left(x\right)\right)}\right)}{y}\right| \]
      21. unsub-negN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      22. lower--.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      23. metadata-eval99.9

        \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{-4} - x\right)}{y}\right| \]
    4. Applied rewrites99.9%

      \[\leadsto \color{blue}{\left|\frac{\mathsf{fma}\left(x, z, -4 - x\right)}{y}\right|} \]
    5. Taylor expanded in x around 0

      \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{-4}\right)}{y}\right| \]
    6. Step-by-step derivation
      1. Applied rewrites99.1%

        \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{-4}\right)}{y}\right| \]

      if 5.6000000000000001e-14 < x

      1. Initial program 81.8%

        \[\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right| \]
      2. Add Preprocessing
      3. Taylor expanded in x around inf

        \[\leadsto \left|\color{blue}{x \cdot \left(\frac{1}{y} - \frac{z}{y}\right)}\right| \]
      4. Step-by-step derivation
        1. distribute-lft-out--N/A

          \[\leadsto \left|\color{blue}{x \cdot \frac{1}{y} - x \cdot \frac{z}{y}}\right| \]
        2. associate-*r/N/A

          \[\leadsto \left|\color{blue}{\frac{x \cdot 1}{y}} - x \cdot \frac{z}{y}\right| \]
        3. *-rgt-identityN/A

          \[\leadsto \left|\frac{\color{blue}{x}}{y} - x \cdot \frac{z}{y}\right| \]
        4. associate-/l*N/A

          \[\leadsto \left|\frac{x}{y} - \color{blue}{\frac{x \cdot z}{y}}\right| \]
        5. div-subN/A

          \[\leadsto \left|\color{blue}{\frac{x - x \cdot z}{y}}\right| \]
        6. lower-/.f64N/A

          \[\leadsto \left|\color{blue}{\frac{x - x \cdot z}{y}}\right| \]
        7. lower--.f64N/A

          \[\leadsto \left|\frac{\color{blue}{x - x \cdot z}}{y}\right| \]
        8. lower-*.f6493.6

          \[\leadsto \left|\frac{x - \color{blue}{x \cdot z}}{y}\right| \]
      5. Applied rewrites93.6%

        \[\leadsto \left|\color{blue}{\frac{x - x \cdot z}{y}}\right| \]
    7. Recombined 3 regimes into one program.
    8. Add Preprocessing

    Alternative 3: 94.1% accurate, 1.1× speedup?

    \[\begin{array}{l} y_m = \left|y\right| \\ \begin{array}{l} t_0 := \left|\frac{x - x \cdot z}{y\_m}\right|\\ \mathbf{if}\;x \leq -1860000000000:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;x \leq 5.6 \cdot 10^{-14}:\\ \;\;\;\;\left|\frac{\mathsf{fma}\left(x, z, -4\right)}{y\_m}\right|\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
    y_m = (fabs.f64 y)
    (FPCore (x y_m z)
     :precision binary64
     (let* ((t_0 (fabs (/ (- x (* x z)) y_m))))
       (if (<= x -1860000000000.0)
         t_0
         (if (<= x 5.6e-14) (fabs (/ (fma x z -4.0) y_m)) t_0))))
    y_m = fabs(y);
    double code(double x, double y_m, double z) {
    	double t_0 = fabs(((x - (x * z)) / y_m));
    	double tmp;
    	if (x <= -1860000000000.0) {
    		tmp = t_0;
    	} else if (x <= 5.6e-14) {
    		tmp = fabs((fma(x, z, -4.0) / y_m));
    	} else {
    		tmp = t_0;
    	}
    	return tmp;
    }
    
    y_m = abs(y)
    function code(x, y_m, z)
    	t_0 = abs(Float64(Float64(x - Float64(x * z)) / y_m))
    	tmp = 0.0
    	if (x <= -1860000000000.0)
    		tmp = t_0;
    	elseif (x <= 5.6e-14)
    		tmp = abs(Float64(fma(x, z, -4.0) / y_m));
    	else
    		tmp = t_0;
    	end
    	return tmp
    end
    
    y_m = N[Abs[y], $MachinePrecision]
    code[x_, y$95$m_, z_] := Block[{t$95$0 = N[Abs[N[(N[(x - N[(x * z), $MachinePrecision]), $MachinePrecision] / y$95$m), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[x, -1860000000000.0], t$95$0, If[LessEqual[x, 5.6e-14], N[Abs[N[(N[(x * z + -4.0), $MachinePrecision] / y$95$m), $MachinePrecision]], $MachinePrecision], t$95$0]]]
    
    \begin{array}{l}
    y_m = \left|y\right|
    
    \\
    \begin{array}{l}
    t_0 := \left|\frac{x - x \cdot z}{y\_m}\right|\\
    \mathbf{if}\;x \leq -1860000000000:\\
    \;\;\;\;t\_0\\
    
    \mathbf{elif}\;x \leq 5.6 \cdot 10^{-14}:\\
    \;\;\;\;\left|\frac{\mathsf{fma}\left(x, z, -4\right)}{y\_m}\right|\\
    
    \mathbf{else}:\\
    \;\;\;\;t\_0\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if x < -1.86e12 or 5.6000000000000001e-14 < x

      1. Initial program 84.1%

        \[\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right| \]
      2. Add Preprocessing
      3. Taylor expanded in x around inf

        \[\leadsto \left|\color{blue}{x \cdot \left(\frac{1}{y} - \frac{z}{y}\right)}\right| \]
      4. Step-by-step derivation
        1. distribute-lft-out--N/A

          \[\leadsto \left|\color{blue}{x \cdot \frac{1}{y} - x \cdot \frac{z}{y}}\right| \]
        2. associate-*r/N/A

          \[\leadsto \left|\color{blue}{\frac{x \cdot 1}{y}} - x \cdot \frac{z}{y}\right| \]
        3. *-rgt-identityN/A

          \[\leadsto \left|\frac{\color{blue}{x}}{y} - x \cdot \frac{z}{y}\right| \]
        4. associate-/l*N/A

          \[\leadsto \left|\frac{x}{y} - \color{blue}{\frac{x \cdot z}{y}}\right| \]
        5. div-subN/A

          \[\leadsto \left|\color{blue}{\frac{x - x \cdot z}{y}}\right| \]
        6. lower-/.f64N/A

          \[\leadsto \left|\color{blue}{\frac{x - x \cdot z}{y}}\right| \]
        7. lower--.f64N/A

          \[\leadsto \left|\frac{\color{blue}{x - x \cdot z}}{y}\right| \]
        8. lower-*.f6494.1

          \[\leadsto \left|\frac{x - \color{blue}{x \cdot z}}{y}\right| \]
      5. Applied rewrites94.1%

        \[\leadsto \left|\color{blue}{\frac{x - x \cdot z}{y}}\right| \]

      if -1.86e12 < x < 5.6000000000000001e-14

      1. Initial program 95.1%

        \[\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right| \]
      2. Add Preprocessing
      3. Step-by-step derivation
        1. lift-fabs.f64N/A

          \[\leadsto \color{blue}{\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right|} \]
        2. neg-fabsN/A

          \[\leadsto \color{blue}{\left|\mathsf{neg}\left(\left(\frac{x + 4}{y} - \frac{x}{y} \cdot z\right)\right)\right|} \]
        3. lower-fabs.f64N/A

          \[\leadsto \color{blue}{\left|\mathsf{neg}\left(\left(\frac{x + 4}{y} - \frac{x}{y} \cdot z\right)\right)\right|} \]
        4. lift--.f64N/A

          \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\frac{x + 4}{y} - \frac{x}{y} \cdot z\right)}\right)\right| \]
        5. sub-negN/A

          \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\frac{x + 4}{y} + \left(\mathsf{neg}\left(\frac{x}{y} \cdot z\right)\right)\right)}\right)\right| \]
        6. +-commutativeN/A

          \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\left(\mathsf{neg}\left(\frac{x}{y} \cdot z\right)\right) + \frac{x + 4}{y}\right)}\right)\right| \]
        7. distribute-neg-inN/A

          \[\leadsto \left|\color{blue}{\left(\mathsf{neg}\left(\left(\mathsf{neg}\left(\frac{x}{y} \cdot z\right)\right)\right)\right) + \left(\mathsf{neg}\left(\frac{x + 4}{y}\right)\right)}\right| \]
        8. remove-double-negN/A

          \[\leadsto \left|\color{blue}{\frac{x}{y} \cdot z} + \left(\mathsf{neg}\left(\frac{x + 4}{y}\right)\right)\right| \]
        9. sub-negN/A

          \[\leadsto \left|\color{blue}{\frac{x}{y} \cdot z - \frac{x + 4}{y}}\right| \]
        10. lift-*.f64N/A

          \[\leadsto \left|\color{blue}{\frac{x}{y} \cdot z} - \frac{x + 4}{y}\right| \]
        11. lift-/.f64N/A

          \[\leadsto \left|\color{blue}{\frac{x}{y}} \cdot z - \frac{x + 4}{y}\right| \]
        12. associate-*l/N/A

          \[\leadsto \left|\color{blue}{\frac{x \cdot z}{y}} - \frac{x + 4}{y}\right| \]
        13. lift-/.f64N/A

          \[\leadsto \left|\frac{x \cdot z}{y} - \color{blue}{\frac{x + 4}{y}}\right| \]
        14. sub-divN/A

          \[\leadsto \left|\color{blue}{\frac{x \cdot z - \left(x + 4\right)}{y}}\right| \]
        15. lower-/.f64N/A

          \[\leadsto \left|\color{blue}{\frac{x \cdot z - \left(x + 4\right)}{y}}\right| \]
        16. sub-negN/A

          \[\leadsto \left|\frac{\color{blue}{x \cdot z + \left(\mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
        17. lower-fma.f64N/A

          \[\leadsto \left|\frac{\color{blue}{\mathsf{fma}\left(x, z, \mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
        18. lift-+.f64N/A

          \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \mathsf{neg}\left(\color{blue}{\left(x + 4\right)}\right)\right)}{y}\right| \]
        19. +-commutativeN/A

          \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \mathsf{neg}\left(\color{blue}{\left(4 + x\right)}\right)\right)}{y}\right| \]
        20. distribute-neg-inN/A

          \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) + \left(\mathsf{neg}\left(x\right)\right)}\right)}{y}\right| \]
        21. unsub-negN/A

          \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
        22. lower--.f64N/A

          \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
        23. metadata-eval99.9

          \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{-4} - x\right)}{y}\right| \]
      4. Applied rewrites99.9%

        \[\leadsto \color{blue}{\left|\frac{\mathsf{fma}\left(x, z, -4 - x\right)}{y}\right|} \]
      5. Taylor expanded in x around 0

        \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{-4}\right)}{y}\right| \]
      6. Step-by-step derivation
        1. Applied rewrites99.1%

          \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{-4}\right)}{y}\right| \]
      7. Recombined 2 regimes into one program.
      8. Add Preprocessing

      Alternative 4: 94.6% accurate, 1.1× speedup?

      \[\begin{array}{l} y_m = \left|y\right| \\ \begin{array}{l} t_0 := \left|\frac{\mathsf{fma}\left(x, z, -4\right)}{y\_m}\right|\\ \mathbf{if}\;z \leq -1:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;z \leq 6.4 \cdot 10^{-15}:\\ \;\;\;\;\left|\frac{x + 4}{y\_m}\right|\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
      y_m = (fabs.f64 y)
      (FPCore (x y_m z)
       :precision binary64
       (let* ((t_0 (fabs (/ (fma x z -4.0) y_m))))
         (if (<= z -1.0) t_0 (if (<= z 6.4e-15) (fabs (/ (+ x 4.0) y_m)) t_0))))
      y_m = fabs(y);
      double code(double x, double y_m, double z) {
      	double t_0 = fabs((fma(x, z, -4.0) / y_m));
      	double tmp;
      	if (z <= -1.0) {
      		tmp = t_0;
      	} else if (z <= 6.4e-15) {
      		tmp = fabs(((x + 4.0) / y_m));
      	} else {
      		tmp = t_0;
      	}
      	return tmp;
      }
      
      y_m = abs(y)
      function code(x, y_m, z)
      	t_0 = abs(Float64(fma(x, z, -4.0) / y_m))
      	tmp = 0.0
      	if (z <= -1.0)
      		tmp = t_0;
      	elseif (z <= 6.4e-15)
      		tmp = abs(Float64(Float64(x + 4.0) / y_m));
      	else
      		tmp = t_0;
      	end
      	return tmp
      end
      
      y_m = N[Abs[y], $MachinePrecision]
      code[x_, y$95$m_, z_] := Block[{t$95$0 = N[Abs[N[(N[(x * z + -4.0), $MachinePrecision] / y$95$m), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[z, -1.0], t$95$0, If[LessEqual[z, 6.4e-15], N[Abs[N[(N[(x + 4.0), $MachinePrecision] / y$95$m), $MachinePrecision]], $MachinePrecision], t$95$0]]]
      
      \begin{array}{l}
      y_m = \left|y\right|
      
      \\
      \begin{array}{l}
      t_0 := \left|\frac{\mathsf{fma}\left(x, z, -4\right)}{y\_m}\right|\\
      \mathbf{if}\;z \leq -1:\\
      \;\;\;\;t\_0\\
      
      \mathbf{elif}\;z \leq 6.4 \cdot 10^{-15}:\\
      \;\;\;\;\left|\frac{x + 4}{y\_m}\right|\\
      
      \mathbf{else}:\\
      \;\;\;\;t\_0\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if z < -1 or 6.3999999999999999e-15 < z

        1. Initial program 88.9%

          \[\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right| \]
        2. Add Preprocessing
        3. Step-by-step derivation
          1. lift-fabs.f64N/A

            \[\leadsto \color{blue}{\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right|} \]
          2. neg-fabsN/A

            \[\leadsto \color{blue}{\left|\mathsf{neg}\left(\left(\frac{x + 4}{y} - \frac{x}{y} \cdot z\right)\right)\right|} \]
          3. lower-fabs.f64N/A

            \[\leadsto \color{blue}{\left|\mathsf{neg}\left(\left(\frac{x + 4}{y} - \frac{x}{y} \cdot z\right)\right)\right|} \]
          4. lift--.f64N/A

            \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\frac{x + 4}{y} - \frac{x}{y} \cdot z\right)}\right)\right| \]
          5. sub-negN/A

            \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\frac{x + 4}{y} + \left(\mathsf{neg}\left(\frac{x}{y} \cdot z\right)\right)\right)}\right)\right| \]
          6. +-commutativeN/A

            \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\left(\mathsf{neg}\left(\frac{x}{y} \cdot z\right)\right) + \frac{x + 4}{y}\right)}\right)\right| \]
          7. distribute-neg-inN/A

            \[\leadsto \left|\color{blue}{\left(\mathsf{neg}\left(\left(\mathsf{neg}\left(\frac{x}{y} \cdot z\right)\right)\right)\right) + \left(\mathsf{neg}\left(\frac{x + 4}{y}\right)\right)}\right| \]
          8. remove-double-negN/A

            \[\leadsto \left|\color{blue}{\frac{x}{y} \cdot z} + \left(\mathsf{neg}\left(\frac{x + 4}{y}\right)\right)\right| \]
          9. sub-negN/A

            \[\leadsto \left|\color{blue}{\frac{x}{y} \cdot z - \frac{x + 4}{y}}\right| \]
          10. lift-*.f64N/A

            \[\leadsto \left|\color{blue}{\frac{x}{y} \cdot z} - \frac{x + 4}{y}\right| \]
          11. lift-/.f64N/A

            \[\leadsto \left|\color{blue}{\frac{x}{y}} \cdot z - \frac{x + 4}{y}\right| \]
          12. associate-*l/N/A

            \[\leadsto \left|\color{blue}{\frac{x \cdot z}{y}} - \frac{x + 4}{y}\right| \]
          13. lift-/.f64N/A

            \[\leadsto \left|\frac{x \cdot z}{y} - \color{blue}{\frac{x + 4}{y}}\right| \]
          14. sub-divN/A

            \[\leadsto \left|\color{blue}{\frac{x \cdot z - \left(x + 4\right)}{y}}\right| \]
          15. lower-/.f64N/A

            \[\leadsto \left|\color{blue}{\frac{x \cdot z - \left(x + 4\right)}{y}}\right| \]
          16. sub-negN/A

            \[\leadsto \left|\frac{\color{blue}{x \cdot z + \left(\mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
          17. lower-fma.f64N/A

            \[\leadsto \left|\frac{\color{blue}{\mathsf{fma}\left(x, z, \mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
          18. lift-+.f64N/A

            \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \mathsf{neg}\left(\color{blue}{\left(x + 4\right)}\right)\right)}{y}\right| \]
          19. +-commutativeN/A

            \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \mathsf{neg}\left(\color{blue}{\left(4 + x\right)}\right)\right)}{y}\right| \]
          20. distribute-neg-inN/A

            \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) + \left(\mathsf{neg}\left(x\right)\right)}\right)}{y}\right| \]
          21. unsub-negN/A

            \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
          22. lower--.f64N/A

            \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
          23. metadata-eval95.6

            \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{-4} - x\right)}{y}\right| \]
        4. Applied rewrites95.6%

          \[\leadsto \color{blue}{\left|\frac{\mathsf{fma}\left(x, z, -4 - x\right)}{y}\right|} \]
        5. Taylor expanded in x around 0

          \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{-4}\right)}{y}\right| \]
        6. Step-by-step derivation
          1. Applied rewrites94.2%

            \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{-4}\right)}{y}\right| \]

          if -1 < z < 6.3999999999999999e-15

          1. Initial program 91.1%

            \[\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right| \]
          2. Add Preprocessing
          3. Taylor expanded in z around 0

            \[\leadsto \left|\color{blue}{4 \cdot \frac{1}{y} + \frac{x}{y}}\right| \]
          4. Step-by-step derivation
            1. *-rgt-identityN/A

              \[\leadsto \left|4 \cdot \frac{1}{y} + \frac{\color{blue}{x \cdot 1}}{y}\right| \]
            2. associate-*r/N/A

              \[\leadsto \left|4 \cdot \frac{1}{y} + \color{blue}{x \cdot \frac{1}{y}}\right| \]
            3. distribute-rgt-outN/A

              \[\leadsto \left|\color{blue}{\frac{1}{y} \cdot \left(4 + x\right)}\right| \]
            4. associate-*l/N/A

              \[\leadsto \left|\color{blue}{\frac{1 \cdot \left(4 + x\right)}{y}}\right| \]
            5. metadata-evalN/A

              \[\leadsto \left|\frac{\color{blue}{\left(-1 \cdot -1\right)} \cdot \left(4 + x\right)}{y}\right| \]
            6. associate-*r*N/A

              \[\leadsto \left|\frac{\color{blue}{-1 \cdot \left(-1 \cdot \left(4 + x\right)\right)}}{y}\right| \]
            7. associate-*r/N/A

              \[\leadsto \left|\color{blue}{-1 \cdot \frac{-1 \cdot \left(4 + x\right)}{y}}\right| \]
            8. neg-mul-1N/A

              \[\leadsto \left|\color{blue}{\mathsf{neg}\left(\frac{-1 \cdot \left(4 + x\right)}{y}\right)}\right| \]
            9. mul-1-negN/A

              \[\leadsto \left|\mathsf{neg}\left(\frac{\color{blue}{\mathsf{neg}\left(\left(4 + x\right)\right)}}{y}\right)\right| \]
            10. distribute-frac-negN/A

              \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\mathsf{neg}\left(\frac{4 + x}{y}\right)\right)}\right)\right| \]
            11. remove-double-negN/A

              \[\leadsto \left|\color{blue}{\frac{4 + x}{y}}\right| \]
            12. lower-/.f64N/A

              \[\leadsto \left|\color{blue}{\frac{4 + x}{y}}\right| \]
            13. lower-+.f6499.1

              \[\leadsto \left|\frac{\color{blue}{4 + x}}{y}\right| \]
          5. Applied rewrites99.1%

            \[\leadsto \left|\color{blue}{\frac{4 + x}{y}}\right| \]
        7. Recombined 2 regimes into one program.
        8. Final simplification96.6%

          \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq -1:\\ \;\;\;\;\left|\frac{\mathsf{fma}\left(x, z, -4\right)}{y}\right|\\ \mathbf{elif}\;z \leq 6.4 \cdot 10^{-15}:\\ \;\;\;\;\left|\frac{x + 4}{y}\right|\\ \mathbf{else}:\\ \;\;\;\;\left|\frac{\mathsf{fma}\left(x, z, -4\right)}{y}\right|\\ \end{array} \]
        9. Add Preprocessing

        Alternative 5: 83.2% accurate, 1.2× speedup?

        \[\begin{array}{l} y_m = \left|y\right| \\ \begin{array}{l} t_0 := \left|\frac{x \cdot z}{y\_m}\right|\\ \mathbf{if}\;z \leq -1.05 \cdot 10^{+77}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;z \leq 2.5 \cdot 10^{+48}:\\ \;\;\;\;\left|\frac{x + 4}{y\_m}\right|\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
        y_m = (fabs.f64 y)
        (FPCore (x y_m z)
         :precision binary64
         (let* ((t_0 (fabs (/ (* x z) y_m))))
           (if (<= z -1.05e+77) t_0 (if (<= z 2.5e+48) (fabs (/ (+ x 4.0) y_m)) t_0))))
        y_m = fabs(y);
        double code(double x, double y_m, double z) {
        	double t_0 = fabs(((x * z) / y_m));
        	double tmp;
        	if (z <= -1.05e+77) {
        		tmp = t_0;
        	} else if (z <= 2.5e+48) {
        		tmp = fabs(((x + 4.0) / y_m));
        	} else {
        		tmp = t_0;
        	}
        	return tmp;
        }
        
        y_m = abs(y)
        real(8) function code(x, y_m, z)
            real(8), intent (in) :: x
            real(8), intent (in) :: y_m
            real(8), intent (in) :: z
            real(8) :: t_0
            real(8) :: tmp
            t_0 = abs(((x * z) / y_m))
            if (z <= (-1.05d+77)) then
                tmp = t_0
            else if (z <= 2.5d+48) then
                tmp = abs(((x + 4.0d0) / y_m))
            else
                tmp = t_0
            end if
            code = tmp
        end function
        
        y_m = Math.abs(y);
        public static double code(double x, double y_m, double z) {
        	double t_0 = Math.abs(((x * z) / y_m));
        	double tmp;
        	if (z <= -1.05e+77) {
        		tmp = t_0;
        	} else if (z <= 2.5e+48) {
        		tmp = Math.abs(((x + 4.0) / y_m));
        	} else {
        		tmp = t_0;
        	}
        	return tmp;
        }
        
        y_m = math.fabs(y)
        def code(x, y_m, z):
        	t_0 = math.fabs(((x * z) / y_m))
        	tmp = 0
        	if z <= -1.05e+77:
        		tmp = t_0
        	elif z <= 2.5e+48:
        		tmp = math.fabs(((x + 4.0) / y_m))
        	else:
        		tmp = t_0
        	return tmp
        
        y_m = abs(y)
        function code(x, y_m, z)
        	t_0 = abs(Float64(Float64(x * z) / y_m))
        	tmp = 0.0
        	if (z <= -1.05e+77)
        		tmp = t_0;
        	elseif (z <= 2.5e+48)
        		tmp = abs(Float64(Float64(x + 4.0) / y_m));
        	else
        		tmp = t_0;
        	end
        	return tmp
        end
        
        y_m = abs(y);
        function tmp_2 = code(x, y_m, z)
        	t_0 = abs(((x * z) / y_m));
        	tmp = 0.0;
        	if (z <= -1.05e+77)
        		tmp = t_0;
        	elseif (z <= 2.5e+48)
        		tmp = abs(((x + 4.0) / y_m));
        	else
        		tmp = t_0;
        	end
        	tmp_2 = tmp;
        end
        
        y_m = N[Abs[y], $MachinePrecision]
        code[x_, y$95$m_, z_] := Block[{t$95$0 = N[Abs[N[(N[(x * z), $MachinePrecision] / y$95$m), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[z, -1.05e+77], t$95$0, If[LessEqual[z, 2.5e+48], N[Abs[N[(N[(x + 4.0), $MachinePrecision] / y$95$m), $MachinePrecision]], $MachinePrecision], t$95$0]]]
        
        \begin{array}{l}
        y_m = \left|y\right|
        
        \\
        \begin{array}{l}
        t_0 := \left|\frac{x \cdot z}{y\_m}\right|\\
        \mathbf{if}\;z \leq -1.05 \cdot 10^{+77}:\\
        \;\;\;\;t\_0\\
        
        \mathbf{elif}\;z \leq 2.5 \cdot 10^{+48}:\\
        \;\;\;\;\left|\frac{x + 4}{y\_m}\right|\\
        
        \mathbf{else}:\\
        \;\;\;\;t\_0\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if z < -1.0499999999999999e77 or 2.49999999999999987e48 < z

          1. Initial program 88.4%

            \[\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right| \]
          2. Add Preprocessing
          3. Step-by-step derivation
            1. lift-fabs.f64N/A

              \[\leadsto \color{blue}{\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right|} \]
            2. neg-fabsN/A

              \[\leadsto \color{blue}{\left|\mathsf{neg}\left(\left(\frac{x + 4}{y} - \frac{x}{y} \cdot z\right)\right)\right|} \]
            3. lower-fabs.f64N/A

              \[\leadsto \color{blue}{\left|\mathsf{neg}\left(\left(\frac{x + 4}{y} - \frac{x}{y} \cdot z\right)\right)\right|} \]
            4. lift--.f64N/A

              \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\frac{x + 4}{y} - \frac{x}{y} \cdot z\right)}\right)\right| \]
            5. sub-negN/A

              \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\frac{x + 4}{y} + \left(\mathsf{neg}\left(\frac{x}{y} \cdot z\right)\right)\right)}\right)\right| \]
            6. +-commutativeN/A

              \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\left(\mathsf{neg}\left(\frac{x}{y} \cdot z\right)\right) + \frac{x + 4}{y}\right)}\right)\right| \]
            7. distribute-neg-inN/A

              \[\leadsto \left|\color{blue}{\left(\mathsf{neg}\left(\left(\mathsf{neg}\left(\frac{x}{y} \cdot z\right)\right)\right)\right) + \left(\mathsf{neg}\left(\frac{x + 4}{y}\right)\right)}\right| \]
            8. remove-double-negN/A

              \[\leadsto \left|\color{blue}{\frac{x}{y} \cdot z} + \left(\mathsf{neg}\left(\frac{x + 4}{y}\right)\right)\right| \]
            9. sub-negN/A

              \[\leadsto \left|\color{blue}{\frac{x}{y} \cdot z - \frac{x + 4}{y}}\right| \]
            10. lift-*.f64N/A

              \[\leadsto \left|\color{blue}{\frac{x}{y} \cdot z} - \frac{x + 4}{y}\right| \]
            11. lift-/.f64N/A

              \[\leadsto \left|\color{blue}{\frac{x}{y}} \cdot z - \frac{x + 4}{y}\right| \]
            12. associate-*l/N/A

              \[\leadsto \left|\color{blue}{\frac{x \cdot z}{y}} - \frac{x + 4}{y}\right| \]
            13. lift-/.f64N/A

              \[\leadsto \left|\frac{x \cdot z}{y} - \color{blue}{\frac{x + 4}{y}}\right| \]
            14. sub-divN/A

              \[\leadsto \left|\color{blue}{\frac{x \cdot z - \left(x + 4\right)}{y}}\right| \]
            15. lower-/.f64N/A

              \[\leadsto \left|\color{blue}{\frac{x \cdot z - \left(x + 4\right)}{y}}\right| \]
            16. sub-negN/A

              \[\leadsto \left|\frac{\color{blue}{x \cdot z + \left(\mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
            17. lower-fma.f64N/A

              \[\leadsto \left|\frac{\color{blue}{\mathsf{fma}\left(x, z, \mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
            18. lift-+.f64N/A

              \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \mathsf{neg}\left(\color{blue}{\left(x + 4\right)}\right)\right)}{y}\right| \]
            19. +-commutativeN/A

              \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \mathsf{neg}\left(\color{blue}{\left(4 + x\right)}\right)\right)}{y}\right| \]
            20. distribute-neg-inN/A

              \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) + \left(\mathsf{neg}\left(x\right)\right)}\right)}{y}\right| \]
            21. unsub-negN/A

              \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
            22. lower--.f64N/A

              \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
            23. metadata-eval94.7

              \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{-4} - x\right)}{y}\right| \]
          4. Applied rewrites94.7%

            \[\leadsto \color{blue}{\left|\frac{\mathsf{fma}\left(x, z, -4 - x\right)}{y}\right|} \]
          5. Taylor expanded in z around inf

            \[\leadsto \left|\frac{\color{blue}{x \cdot z}}{y}\right| \]
          6. Step-by-step derivation
            1. lower-*.f6477.1

              \[\leadsto \left|\frac{\color{blue}{x \cdot z}}{y}\right| \]
          7. Applied rewrites77.1%

            \[\leadsto \left|\frac{\color{blue}{x \cdot z}}{y}\right| \]

          if -1.0499999999999999e77 < z < 2.49999999999999987e48

          1. Initial program 91.1%

            \[\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right| \]
          2. Add Preprocessing
          3. Taylor expanded in z around 0

            \[\leadsto \left|\color{blue}{4 \cdot \frac{1}{y} + \frac{x}{y}}\right| \]
          4. Step-by-step derivation
            1. *-rgt-identityN/A

              \[\leadsto \left|4 \cdot \frac{1}{y} + \frac{\color{blue}{x \cdot 1}}{y}\right| \]
            2. associate-*r/N/A

              \[\leadsto \left|4 \cdot \frac{1}{y} + \color{blue}{x \cdot \frac{1}{y}}\right| \]
            3. distribute-rgt-outN/A

              \[\leadsto \left|\color{blue}{\frac{1}{y} \cdot \left(4 + x\right)}\right| \]
            4. associate-*l/N/A

              \[\leadsto \left|\color{blue}{\frac{1 \cdot \left(4 + x\right)}{y}}\right| \]
            5. metadata-evalN/A

              \[\leadsto \left|\frac{\color{blue}{\left(-1 \cdot -1\right)} \cdot \left(4 + x\right)}{y}\right| \]
            6. associate-*r*N/A

              \[\leadsto \left|\frac{\color{blue}{-1 \cdot \left(-1 \cdot \left(4 + x\right)\right)}}{y}\right| \]
            7. associate-*r/N/A

              \[\leadsto \left|\color{blue}{-1 \cdot \frac{-1 \cdot \left(4 + x\right)}{y}}\right| \]
            8. neg-mul-1N/A

              \[\leadsto \left|\color{blue}{\mathsf{neg}\left(\frac{-1 \cdot \left(4 + x\right)}{y}\right)}\right| \]
            9. mul-1-negN/A

              \[\leadsto \left|\mathsf{neg}\left(\frac{\color{blue}{\mathsf{neg}\left(\left(4 + x\right)\right)}}{y}\right)\right| \]
            10. distribute-frac-negN/A

              \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\mathsf{neg}\left(\frac{4 + x}{y}\right)\right)}\right)\right| \]
            11. remove-double-negN/A

              \[\leadsto \left|\color{blue}{\frac{4 + x}{y}}\right| \]
            12. lower-/.f64N/A

              \[\leadsto \left|\color{blue}{\frac{4 + x}{y}}\right| \]
            13. lower-+.f6495.7

              \[\leadsto \left|\frac{\color{blue}{4 + x}}{y}\right| \]
          5. Applied rewrites95.7%

            \[\leadsto \left|\color{blue}{\frac{4 + x}{y}}\right| \]
        3. Recombined 2 regimes into one program.
        4. Final simplification87.8%

          \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq -1.05 \cdot 10^{+77}:\\ \;\;\;\;\left|\frac{x \cdot z}{y}\right|\\ \mathbf{elif}\;z \leq 2.5 \cdot 10^{+48}:\\ \;\;\;\;\left|\frac{x + 4}{y}\right|\\ \mathbf{else}:\\ \;\;\;\;\left|\frac{x \cdot z}{y}\right|\\ \end{array} \]
        5. Add Preprocessing

        Alternative 6: 68.3% accurate, 1.3× speedup?

        \[\begin{array}{l} y_m = \left|y\right| \\ \begin{array}{l} t_0 := \left|\frac{-x}{y\_m}\right|\\ \mathbf{if}\;x \leq -1.5:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;x \leq 4:\\ \;\;\;\;\left|\frac{4}{y\_m}\right|\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
        y_m = (fabs.f64 y)
        (FPCore (x y_m z)
         :precision binary64
         (let* ((t_0 (fabs (/ (- x) y_m))))
           (if (<= x -1.5) t_0 (if (<= x 4.0) (fabs (/ 4.0 y_m)) t_0))))
        y_m = fabs(y);
        double code(double x, double y_m, double z) {
        	double t_0 = fabs((-x / y_m));
        	double tmp;
        	if (x <= -1.5) {
        		tmp = t_0;
        	} else if (x <= 4.0) {
        		tmp = fabs((4.0 / y_m));
        	} else {
        		tmp = t_0;
        	}
        	return tmp;
        }
        
        y_m = abs(y)
        real(8) function code(x, y_m, z)
            real(8), intent (in) :: x
            real(8), intent (in) :: y_m
            real(8), intent (in) :: z
            real(8) :: t_0
            real(8) :: tmp
            t_0 = abs((-x / y_m))
            if (x <= (-1.5d0)) then
                tmp = t_0
            else if (x <= 4.0d0) then
                tmp = abs((4.0d0 / y_m))
            else
                tmp = t_0
            end if
            code = tmp
        end function
        
        y_m = Math.abs(y);
        public static double code(double x, double y_m, double z) {
        	double t_0 = Math.abs((-x / y_m));
        	double tmp;
        	if (x <= -1.5) {
        		tmp = t_0;
        	} else if (x <= 4.0) {
        		tmp = Math.abs((4.0 / y_m));
        	} else {
        		tmp = t_0;
        	}
        	return tmp;
        }
        
        y_m = math.fabs(y)
        def code(x, y_m, z):
        	t_0 = math.fabs((-x / y_m))
        	tmp = 0
        	if x <= -1.5:
        		tmp = t_0
        	elif x <= 4.0:
        		tmp = math.fabs((4.0 / y_m))
        	else:
        		tmp = t_0
        	return tmp
        
        y_m = abs(y)
        function code(x, y_m, z)
        	t_0 = abs(Float64(Float64(-x) / y_m))
        	tmp = 0.0
        	if (x <= -1.5)
        		tmp = t_0;
        	elseif (x <= 4.0)
        		tmp = abs(Float64(4.0 / y_m));
        	else
        		tmp = t_0;
        	end
        	return tmp
        end
        
        y_m = abs(y);
        function tmp_2 = code(x, y_m, z)
        	t_0 = abs((-x / y_m));
        	tmp = 0.0;
        	if (x <= -1.5)
        		tmp = t_0;
        	elseif (x <= 4.0)
        		tmp = abs((4.0 / y_m));
        	else
        		tmp = t_0;
        	end
        	tmp_2 = tmp;
        end
        
        y_m = N[Abs[y], $MachinePrecision]
        code[x_, y$95$m_, z_] := Block[{t$95$0 = N[Abs[N[((-x) / y$95$m), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[x, -1.5], t$95$0, If[LessEqual[x, 4.0], N[Abs[N[(4.0 / y$95$m), $MachinePrecision]], $MachinePrecision], t$95$0]]]
        
        \begin{array}{l}
        y_m = \left|y\right|
        
        \\
        \begin{array}{l}
        t_0 := \left|\frac{-x}{y\_m}\right|\\
        \mathbf{if}\;x \leq -1.5:\\
        \;\;\;\;t\_0\\
        
        \mathbf{elif}\;x \leq 4:\\
        \;\;\;\;\left|\frac{4}{y\_m}\right|\\
        
        \mathbf{else}:\\
        \;\;\;\;t\_0\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if x < -1.5 or 4 < x

          1. Initial program 84.6%

            \[\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right| \]
          2. Add Preprocessing
          3. Step-by-step derivation
            1. lift-fabs.f64N/A

              \[\leadsto \color{blue}{\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right|} \]
            2. neg-fabsN/A

              \[\leadsto \color{blue}{\left|\mathsf{neg}\left(\left(\frac{x + 4}{y} - \frac{x}{y} \cdot z\right)\right)\right|} \]
            3. lower-fabs.f64N/A

              \[\leadsto \color{blue}{\left|\mathsf{neg}\left(\left(\frac{x + 4}{y} - \frac{x}{y} \cdot z\right)\right)\right|} \]
            4. lift--.f64N/A

              \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\frac{x + 4}{y} - \frac{x}{y} \cdot z\right)}\right)\right| \]
            5. sub-negN/A

              \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\frac{x + 4}{y} + \left(\mathsf{neg}\left(\frac{x}{y} \cdot z\right)\right)\right)}\right)\right| \]
            6. +-commutativeN/A

              \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\left(\mathsf{neg}\left(\frac{x}{y} \cdot z\right)\right) + \frac{x + 4}{y}\right)}\right)\right| \]
            7. distribute-neg-inN/A

              \[\leadsto \left|\color{blue}{\left(\mathsf{neg}\left(\left(\mathsf{neg}\left(\frac{x}{y} \cdot z\right)\right)\right)\right) + \left(\mathsf{neg}\left(\frac{x + 4}{y}\right)\right)}\right| \]
            8. remove-double-negN/A

              \[\leadsto \left|\color{blue}{\frac{x}{y} \cdot z} + \left(\mathsf{neg}\left(\frac{x + 4}{y}\right)\right)\right| \]
            9. sub-negN/A

              \[\leadsto \left|\color{blue}{\frac{x}{y} \cdot z - \frac{x + 4}{y}}\right| \]
            10. lift-*.f64N/A

              \[\leadsto \left|\color{blue}{\frac{x}{y} \cdot z} - \frac{x + 4}{y}\right| \]
            11. lift-/.f64N/A

              \[\leadsto \left|\color{blue}{\frac{x}{y}} \cdot z - \frac{x + 4}{y}\right| \]
            12. associate-*l/N/A

              \[\leadsto \left|\color{blue}{\frac{x \cdot z}{y}} - \frac{x + 4}{y}\right| \]
            13. lift-/.f64N/A

              \[\leadsto \left|\frac{x \cdot z}{y} - \color{blue}{\frac{x + 4}{y}}\right| \]
            14. sub-divN/A

              \[\leadsto \left|\color{blue}{\frac{x \cdot z - \left(x + 4\right)}{y}}\right| \]
            15. lower-/.f64N/A

              \[\leadsto \left|\color{blue}{\frac{x \cdot z - \left(x + 4\right)}{y}}\right| \]
            16. sub-negN/A

              \[\leadsto \left|\frac{\color{blue}{x \cdot z + \left(\mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
            17. lower-fma.f64N/A

              \[\leadsto \left|\frac{\color{blue}{\mathsf{fma}\left(x, z, \mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
            18. lift-+.f64N/A

              \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \mathsf{neg}\left(\color{blue}{\left(x + 4\right)}\right)\right)}{y}\right| \]
            19. +-commutativeN/A

              \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \mathsf{neg}\left(\color{blue}{\left(4 + x\right)}\right)\right)}{y}\right| \]
            20. distribute-neg-inN/A

              \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) + \left(\mathsf{neg}\left(x\right)\right)}\right)}{y}\right| \]
            21. unsub-negN/A

              \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
            22. lower--.f64N/A

              \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
            23. metadata-eval95.4

              \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{-4} - x\right)}{y}\right| \]
          4. Applied rewrites95.4%

            \[\leadsto \color{blue}{\left|\frac{\mathsf{fma}\left(x, z, -4 - x\right)}{y}\right|} \]
          5. Taylor expanded in z around 0

            \[\leadsto \left|\frac{\color{blue}{-1 \cdot \left(4 + x\right)}}{y}\right| \]
          6. Step-by-step derivation
            1. distribute-lft-inN/A

              \[\leadsto \left|\frac{\color{blue}{-1 \cdot 4 + -1 \cdot x}}{y}\right| \]
            2. metadata-evalN/A

              \[\leadsto \left|\frac{\color{blue}{-4} + -1 \cdot x}{y}\right| \]
            3. mul-1-negN/A

              \[\leadsto \left|\frac{-4 + \color{blue}{\left(\mathsf{neg}\left(x\right)\right)}}{y}\right| \]
            4. unsub-negN/A

              \[\leadsto \left|\frac{\color{blue}{-4 - x}}{y}\right| \]
            5. lower--.f6462.7

              \[\leadsto \left|\frac{\color{blue}{-4 - x}}{y}\right| \]
          7. Applied rewrites62.7%

            \[\leadsto \left|\frac{\color{blue}{-4 - x}}{y}\right| \]
          8. Taylor expanded in x around inf

            \[\leadsto \left|\frac{-1 \cdot \color{blue}{x}}{y}\right| \]
          9. Step-by-step derivation
            1. Applied rewrites61.9%

              \[\leadsto \left|\frac{-x}{y}\right| \]

            if -1.5 < x < 4

            1. Initial program 95.0%

              \[\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right| \]
            2. Add Preprocessing
            3. Taylor expanded in x around 0

              \[\leadsto \left|\color{blue}{\frac{4}{y}}\right| \]
            4. Step-by-step derivation
              1. lower-/.f6473.4

                \[\leadsto \left|\color{blue}{\frac{4}{y}}\right| \]
            5. Applied rewrites73.4%

              \[\leadsto \left|\color{blue}{\frac{4}{y}}\right| \]
          10. Recombined 2 regimes into one program.
          11. Add Preprocessing

          Alternative 7: 95.5% accurate, 1.6× speedup?

          \[\begin{array}{l} y_m = \left|y\right| \\ \left|\frac{\mathsf{fma}\left(x, z, -4 - x\right)}{y\_m}\right| \end{array} \]
          y_m = (fabs.f64 y)
          (FPCore (x y_m z) :precision binary64 (fabs (/ (fma x z (- -4.0 x)) y_m)))
          y_m = fabs(y);
          double code(double x, double y_m, double z) {
          	return fabs((fma(x, z, (-4.0 - x)) / y_m));
          }
          
          y_m = abs(y)
          function code(x, y_m, z)
          	return abs(Float64(fma(x, z, Float64(-4.0 - x)) / y_m))
          end
          
          y_m = N[Abs[y], $MachinePrecision]
          code[x_, y$95$m_, z_] := N[Abs[N[(N[(x * z + N[(-4.0 - x), $MachinePrecision]), $MachinePrecision] / y$95$m), $MachinePrecision]], $MachinePrecision]
          
          \begin{array}{l}
          y_m = \left|y\right|
          
          \\
          \left|\frac{\mathsf{fma}\left(x, z, -4 - x\right)}{y\_m}\right|
          \end{array}
          
          Derivation
          1. Initial program 90.0%

            \[\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right| \]
          2. Add Preprocessing
          3. Step-by-step derivation
            1. lift-fabs.f64N/A

              \[\leadsto \color{blue}{\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right|} \]
            2. neg-fabsN/A

              \[\leadsto \color{blue}{\left|\mathsf{neg}\left(\left(\frac{x + 4}{y} - \frac{x}{y} \cdot z\right)\right)\right|} \]
            3. lower-fabs.f64N/A

              \[\leadsto \color{blue}{\left|\mathsf{neg}\left(\left(\frac{x + 4}{y} - \frac{x}{y} \cdot z\right)\right)\right|} \]
            4. lift--.f64N/A

              \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\frac{x + 4}{y} - \frac{x}{y} \cdot z\right)}\right)\right| \]
            5. sub-negN/A

              \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\frac{x + 4}{y} + \left(\mathsf{neg}\left(\frac{x}{y} \cdot z\right)\right)\right)}\right)\right| \]
            6. +-commutativeN/A

              \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\left(\mathsf{neg}\left(\frac{x}{y} \cdot z\right)\right) + \frac{x + 4}{y}\right)}\right)\right| \]
            7. distribute-neg-inN/A

              \[\leadsto \left|\color{blue}{\left(\mathsf{neg}\left(\left(\mathsf{neg}\left(\frac{x}{y} \cdot z\right)\right)\right)\right) + \left(\mathsf{neg}\left(\frac{x + 4}{y}\right)\right)}\right| \]
            8. remove-double-negN/A

              \[\leadsto \left|\color{blue}{\frac{x}{y} \cdot z} + \left(\mathsf{neg}\left(\frac{x + 4}{y}\right)\right)\right| \]
            9. sub-negN/A

              \[\leadsto \left|\color{blue}{\frac{x}{y} \cdot z - \frac{x + 4}{y}}\right| \]
            10. lift-*.f64N/A

              \[\leadsto \left|\color{blue}{\frac{x}{y} \cdot z} - \frac{x + 4}{y}\right| \]
            11. lift-/.f64N/A

              \[\leadsto \left|\color{blue}{\frac{x}{y}} \cdot z - \frac{x + 4}{y}\right| \]
            12. associate-*l/N/A

              \[\leadsto \left|\color{blue}{\frac{x \cdot z}{y}} - \frac{x + 4}{y}\right| \]
            13. lift-/.f64N/A

              \[\leadsto \left|\frac{x \cdot z}{y} - \color{blue}{\frac{x + 4}{y}}\right| \]
            14. sub-divN/A

              \[\leadsto \left|\color{blue}{\frac{x \cdot z - \left(x + 4\right)}{y}}\right| \]
            15. lower-/.f64N/A

              \[\leadsto \left|\color{blue}{\frac{x \cdot z - \left(x + 4\right)}{y}}\right| \]
            16. sub-negN/A

              \[\leadsto \left|\frac{\color{blue}{x \cdot z + \left(\mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
            17. lower-fma.f64N/A

              \[\leadsto \left|\frac{\color{blue}{\mathsf{fma}\left(x, z, \mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
            18. lift-+.f64N/A

              \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \mathsf{neg}\left(\color{blue}{\left(x + 4\right)}\right)\right)}{y}\right| \]
            19. +-commutativeN/A

              \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \mathsf{neg}\left(\color{blue}{\left(4 + x\right)}\right)\right)}{y}\right| \]
            20. distribute-neg-inN/A

              \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) + \left(\mathsf{neg}\left(x\right)\right)}\right)}{y}\right| \]
            21. unsub-negN/A

              \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
            22. lower--.f64N/A

              \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
            23. metadata-eval97.7

              \[\leadsto \left|\frac{\mathsf{fma}\left(x, z, \color{blue}{-4} - x\right)}{y}\right| \]
          4. Applied rewrites97.7%

            \[\leadsto \color{blue}{\left|\frac{\mathsf{fma}\left(x, z, -4 - x\right)}{y}\right|} \]
          5. Add Preprocessing

          Alternative 8: 69.3% accurate, 2.1× speedup?

          \[\begin{array}{l} y_m = \left|y\right| \\ \left|\frac{x + 4}{y\_m}\right| \end{array} \]
          y_m = (fabs.f64 y)
          (FPCore (x y_m z) :precision binary64 (fabs (/ (+ x 4.0) y_m)))
          y_m = fabs(y);
          double code(double x, double y_m, double z) {
          	return fabs(((x + 4.0) / y_m));
          }
          
          y_m = abs(y)
          real(8) function code(x, y_m, z)
              real(8), intent (in) :: x
              real(8), intent (in) :: y_m
              real(8), intent (in) :: z
              code = abs(((x + 4.0d0) / y_m))
          end function
          
          y_m = Math.abs(y);
          public static double code(double x, double y_m, double z) {
          	return Math.abs(((x + 4.0) / y_m));
          }
          
          y_m = math.fabs(y)
          def code(x, y_m, z):
          	return math.fabs(((x + 4.0) / y_m))
          
          y_m = abs(y)
          function code(x, y_m, z)
          	return abs(Float64(Float64(x + 4.0) / y_m))
          end
          
          y_m = abs(y);
          function tmp = code(x, y_m, z)
          	tmp = abs(((x + 4.0) / y_m));
          end
          
          y_m = N[Abs[y], $MachinePrecision]
          code[x_, y$95$m_, z_] := N[Abs[N[(N[(x + 4.0), $MachinePrecision] / y$95$m), $MachinePrecision]], $MachinePrecision]
          
          \begin{array}{l}
          y_m = \left|y\right|
          
          \\
          \left|\frac{x + 4}{y\_m}\right|
          \end{array}
          
          Derivation
          1. Initial program 90.0%

            \[\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right| \]
          2. Add Preprocessing
          3. Taylor expanded in z around 0

            \[\leadsto \left|\color{blue}{4 \cdot \frac{1}{y} + \frac{x}{y}}\right| \]
          4. Step-by-step derivation
            1. *-rgt-identityN/A

              \[\leadsto \left|4 \cdot \frac{1}{y} + \frac{\color{blue}{x \cdot 1}}{y}\right| \]
            2. associate-*r/N/A

              \[\leadsto \left|4 \cdot \frac{1}{y} + \color{blue}{x \cdot \frac{1}{y}}\right| \]
            3. distribute-rgt-outN/A

              \[\leadsto \left|\color{blue}{\frac{1}{y} \cdot \left(4 + x\right)}\right| \]
            4. associate-*l/N/A

              \[\leadsto \left|\color{blue}{\frac{1 \cdot \left(4 + x\right)}{y}}\right| \]
            5. metadata-evalN/A

              \[\leadsto \left|\frac{\color{blue}{\left(-1 \cdot -1\right)} \cdot \left(4 + x\right)}{y}\right| \]
            6. associate-*r*N/A

              \[\leadsto \left|\frac{\color{blue}{-1 \cdot \left(-1 \cdot \left(4 + x\right)\right)}}{y}\right| \]
            7. associate-*r/N/A

              \[\leadsto \left|\color{blue}{-1 \cdot \frac{-1 \cdot \left(4 + x\right)}{y}}\right| \]
            8. neg-mul-1N/A

              \[\leadsto \left|\color{blue}{\mathsf{neg}\left(\frac{-1 \cdot \left(4 + x\right)}{y}\right)}\right| \]
            9. mul-1-negN/A

              \[\leadsto \left|\mathsf{neg}\left(\frac{\color{blue}{\mathsf{neg}\left(\left(4 + x\right)\right)}}{y}\right)\right| \]
            10. distribute-frac-negN/A

              \[\leadsto \left|\mathsf{neg}\left(\color{blue}{\left(\mathsf{neg}\left(\frac{4 + x}{y}\right)\right)}\right)\right| \]
            11. remove-double-negN/A

              \[\leadsto \left|\color{blue}{\frac{4 + x}{y}}\right| \]
            12. lower-/.f64N/A

              \[\leadsto \left|\color{blue}{\frac{4 + x}{y}}\right| \]
            13. lower-+.f6468.4

              \[\leadsto \left|\frac{\color{blue}{4 + x}}{y}\right| \]
          5. Applied rewrites68.4%

            \[\leadsto \left|\color{blue}{\frac{4 + x}{y}}\right| \]
          6. Final simplification68.4%

            \[\leadsto \left|\frac{x + 4}{y}\right| \]
          7. Add Preprocessing

          Alternative 9: 39.8% accurate, 2.6× speedup?

          \[\begin{array}{l} y_m = \left|y\right| \\ \left|\frac{4}{y\_m}\right| \end{array} \]
          y_m = (fabs.f64 y)
          (FPCore (x y_m z) :precision binary64 (fabs (/ 4.0 y_m)))
          y_m = fabs(y);
          double code(double x, double y_m, double z) {
          	return fabs((4.0 / y_m));
          }
          
          y_m = abs(y)
          real(8) function code(x, y_m, z)
              real(8), intent (in) :: x
              real(8), intent (in) :: y_m
              real(8), intent (in) :: z
              code = abs((4.0d0 / y_m))
          end function
          
          y_m = Math.abs(y);
          public static double code(double x, double y_m, double z) {
          	return Math.abs((4.0 / y_m));
          }
          
          y_m = math.fabs(y)
          def code(x, y_m, z):
          	return math.fabs((4.0 / y_m))
          
          y_m = abs(y)
          function code(x, y_m, z)
          	return abs(Float64(4.0 / y_m))
          end
          
          y_m = abs(y);
          function tmp = code(x, y_m, z)
          	tmp = abs((4.0 / y_m));
          end
          
          y_m = N[Abs[y], $MachinePrecision]
          code[x_, y$95$m_, z_] := N[Abs[N[(4.0 / y$95$m), $MachinePrecision]], $MachinePrecision]
          
          \begin{array}{l}
          y_m = \left|y\right|
          
          \\
          \left|\frac{4}{y\_m}\right|
          \end{array}
          
          Derivation
          1. Initial program 90.0%

            \[\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right| \]
          2. Add Preprocessing
          3. Taylor expanded in x around 0

            \[\leadsto \left|\color{blue}{\frac{4}{y}}\right| \]
          4. Step-by-step derivation
            1. lower-/.f6440.7

              \[\leadsto \left|\color{blue}{\frac{4}{y}}\right| \]
          5. Applied rewrites40.7%

            \[\leadsto \left|\color{blue}{\frac{4}{y}}\right| \]
          6. Add Preprocessing

          Reproduce

          ?
          herbie shell --seed 2024216 
          (FPCore (x y z)
            :name "fabs fraction 1"
            :precision binary64
            (fabs (- (/ (+ x 4.0) y) (* (/ x y) z))))