Numeric.SpecFunctions:choose from math-functions-0.1.5.2

Percentage Accurate: 84.5% → 97.8%
Time: 6.3s
Alternatives: 5
Speedup: 1.1×

Specification

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

\\
\frac{x \cdot \left(y + z\right)}{z}
\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 5 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: 84.5% accurate, 1.0× speedup?

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

\\
\frac{x \cdot \left(y + z\right)}{z}
\end{array}

Alternative 1: 97.8% accurate, 0.8× speedup?

\[\begin{array}{l} x\_m = \left|x\right| \\ x\_s = \mathsf{copysign}\left(1, x\right) \\ x\_s \cdot \begin{array}{l} \mathbf{if}\;x\_m \leq 1.8 \cdot 10^{+46}:\\ \;\;\;\;x\_m + \frac{x\_m \cdot y}{z}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(x\_m, \frac{y}{z}, x\_m\right)\\ \end{array} \end{array} \]
x\_m = (fabs.f64 x)
x\_s = (copysign.f64 #s(literal 1 binary64) x)
(FPCore (x_s x_m y z)
 :precision binary64
 (* x_s (if (<= x_m 1.8e+46) (+ x_m (/ (* x_m y) z)) (fma x_m (/ y z) x_m))))
x\_m = fabs(x);
x\_s = copysign(1.0, x);
double code(double x_s, double x_m, double y, double z) {
	double tmp;
	if (x_m <= 1.8e+46) {
		tmp = x_m + ((x_m * y) / z);
	} else {
		tmp = fma(x_m, (y / z), x_m);
	}
	return x_s * tmp;
}
x\_m = abs(x)
x\_s = copysign(1.0, x)
function code(x_s, x_m, y, z)
	tmp = 0.0
	if (x_m <= 1.8e+46)
		tmp = Float64(x_m + Float64(Float64(x_m * y) / z));
	else
		tmp = fma(x_m, Float64(y / z), x_m);
	end
	return Float64(x_s * tmp)
end
x\_m = N[Abs[x], $MachinePrecision]
x\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_, y_, z_] := N[(x$95$s * If[LessEqual[x$95$m, 1.8e+46], N[(x$95$m + N[(N[(x$95$m * y), $MachinePrecision] / z), $MachinePrecision]), $MachinePrecision], N[(x$95$m * N[(y / z), $MachinePrecision] + x$95$m), $MachinePrecision]]), $MachinePrecision]
\begin{array}{l}
x\_m = \left|x\right|
\\
x\_s = \mathsf{copysign}\left(1, x\right)

\\
x\_s \cdot \begin{array}{l}
\mathbf{if}\;x\_m \leq 1.8 \cdot 10^{+46}:\\
\;\;\;\;x\_m + \frac{x\_m \cdot y}{z}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 1.7999999999999999e46

    1. Initial program 88.1%

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

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

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

        \[\leadsto \color{blue}{x \cdot \frac{y + z}{z}} \]
      4. clear-numN/A

        \[\leadsto x \cdot \color{blue}{\frac{1}{\frac{z}{y + z}}} \]
      5. un-div-invN/A

        \[\leadsto \color{blue}{\frac{x}{\frac{z}{y + z}}} \]
      6. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{x}{\frac{z}{y + z}}} \]
      7. lower-/.f6496.9

        \[\leadsto \frac{x}{\color{blue}{\frac{z}{y + z}}} \]
    4. Applied rewrites96.9%

      \[\leadsto \color{blue}{\frac{x}{\frac{z}{y + z}}} \]
    5. Step-by-step derivation
      1. lift-/.f64N/A

        \[\leadsto \color{blue}{\frac{x}{\frac{z}{y + z}}} \]
      2. div-invN/A

        \[\leadsto \color{blue}{x \cdot \frac{1}{\frac{z}{y + z}}} \]
      3. lift-/.f64N/A

        \[\leadsto x \cdot \frac{1}{\color{blue}{\frac{z}{y + z}}} \]
      4. associate-/r/N/A

        \[\leadsto x \cdot \color{blue}{\left(\frac{1}{z} \cdot \left(y + z\right)\right)} \]
      5. lift-+.f64N/A

        \[\leadsto x \cdot \left(\frac{1}{z} \cdot \color{blue}{\left(y + z\right)}\right) \]
      6. distribute-lft-inN/A

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

        \[\leadsto x \cdot \left(\color{blue}{\frac{1}{\frac{z}{y}}} + \frac{1}{z} \cdot z\right) \]
      8. clear-numN/A

        \[\leadsto x \cdot \left(\color{blue}{\frac{y}{z}} + \frac{1}{z} \cdot z\right) \]
      9. lift-/.f64N/A

        \[\leadsto x \cdot \left(\color{blue}{\frac{y}{z}} + \frac{1}{z} \cdot z\right) \]
      10. lft-mult-inverseN/A

        \[\leadsto x \cdot \left(\frac{y}{z} + \color{blue}{1}\right) \]
      11. distribute-lft-outN/A

        \[\leadsto \color{blue}{x \cdot \frac{y}{z} + x \cdot 1} \]
      12. *-rgt-identityN/A

        \[\leadsto x \cdot \frac{y}{z} + \color{blue}{x} \]
      13. lower-+.f64N/A

        \[\leadsto \color{blue}{x \cdot \frac{y}{z} + x} \]
      14. lift-/.f64N/A

        \[\leadsto x \cdot \color{blue}{\frac{y}{z}} + x \]
      15. associate-*r/N/A

        \[\leadsto \color{blue}{\frac{x \cdot y}{z}} + x \]
      16. lift-*.f64N/A

        \[\leadsto \frac{\color{blue}{x \cdot y}}{z} + x \]
      17. lower-/.f6494.0

        \[\leadsto \color{blue}{\frac{x \cdot y}{z}} + x \]
    6. Applied rewrites94.0%

      \[\leadsto \color{blue}{\frac{x \cdot y}{z} + x} \]

    if 1.7999999999999999e46 < x

    1. Initial program 80.7%

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

      \[\leadsto \color{blue}{\frac{x \cdot y + x \cdot z}{z}} \]
    4. Step-by-step derivation
      1. distribute-lft-inN/A

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

        \[\leadsto \color{blue}{x \cdot \frac{y + z}{z}} \]
      3. +-commutativeN/A

        \[\leadsto x \cdot \frac{\color{blue}{z + y}}{z} \]
      4. *-lft-identityN/A

        \[\leadsto x \cdot \frac{z + \color{blue}{1 \cdot y}}{z} \]
      5. metadata-evalN/A

        \[\leadsto x \cdot \frac{z + \color{blue}{\left(\mathsf{neg}\left(-1\right)\right)} \cdot y}{z} \]
      6. cancel-sign-sub-invN/A

        \[\leadsto x \cdot \frac{\color{blue}{z - -1 \cdot y}}{z} \]
      7. div-subN/A

        \[\leadsto x \cdot \color{blue}{\left(\frac{z}{z} - \frac{-1 \cdot y}{z}\right)} \]
      8. *-inversesN/A

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

        \[\leadsto x \cdot \left(1 - \color{blue}{-1 \cdot \frac{y}{z}}\right) \]
      10. unsub-negN/A

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

        \[\leadsto x \cdot \left(1 + \left(\mathsf{neg}\left(\color{blue}{\left(\mathsf{neg}\left(\frac{y}{z}\right)\right)}\right)\right)\right) \]
      12. remove-double-negN/A

        \[\leadsto x \cdot \left(1 + \color{blue}{\frac{y}{z}}\right) \]
      13. +-commutativeN/A

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

        \[\leadsto x \cdot \left(\frac{y}{z} + \color{blue}{\left(\mathsf{neg}\left(-1\right)\right)}\right) \]
      15. sub-negN/A

        \[\leadsto x \cdot \color{blue}{\left(\frac{y}{z} - -1\right)} \]
      16. sub-negN/A

        \[\leadsto x \cdot \color{blue}{\left(\frac{y}{z} + \left(\mathsf{neg}\left(-1\right)\right)\right)} \]
      17. metadata-evalN/A

        \[\leadsto x \cdot \left(\frac{y}{z} + \color{blue}{1}\right) \]
      18. distribute-lft-outN/A

        \[\leadsto \color{blue}{x \cdot \frac{y}{z} + x \cdot 1} \]
      19. *-rgt-identityN/A

        \[\leadsto x \cdot \frac{y}{z} + \color{blue}{x} \]
      20. lower-fma.f64N/A

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

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

      \[\leadsto \color{blue}{\mathsf{fma}\left(x, \frac{y}{z}, x\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification95.4%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 1.8 \cdot 10^{+46}:\\ \;\;\;\;x + \frac{x \cdot y}{z}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(x, \frac{y}{z}, x\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 2: 72.9% accurate, 0.7× speedup?

\[\begin{array}{l} x\_m = \left|x\right| \\ x\_s = \mathsf{copysign}\left(1, x\right) \\ x\_s \cdot \begin{array}{l} \mathbf{if}\;z \leq -2.55 \cdot 10^{-9}:\\ \;\;\;\;\frac{x\_m}{1}\\ \mathbf{elif}\;z \leq 2.8 \cdot 10^{+35}:\\ \;\;\;\;\frac{x\_m \cdot y}{z}\\ \mathbf{else}:\\ \;\;\;\;\frac{x\_m}{1}\\ \end{array} \end{array} \]
x\_m = (fabs.f64 x)
x\_s = (copysign.f64 #s(literal 1 binary64) x)
(FPCore (x_s x_m y z)
 :precision binary64
 (*
  x_s
  (if (<= z -2.55e-9)
    (/ x_m 1.0)
    (if (<= z 2.8e+35) (/ (* x_m y) z) (/ x_m 1.0)))))
x\_m = fabs(x);
x\_s = copysign(1.0, x);
double code(double x_s, double x_m, double y, double z) {
	double tmp;
	if (z <= -2.55e-9) {
		tmp = x_m / 1.0;
	} else if (z <= 2.8e+35) {
		tmp = (x_m * y) / z;
	} else {
		tmp = x_m / 1.0;
	}
	return x_s * tmp;
}
x\_m = abs(x)
x\_s = copysign(1.0d0, x)
real(8) function code(x_s, x_m, y, z)
    real(8), intent (in) :: x_s
    real(8), intent (in) :: x_m
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8) :: tmp
    if (z <= (-2.55d-9)) then
        tmp = x_m / 1.0d0
    else if (z <= 2.8d+35) then
        tmp = (x_m * y) / z
    else
        tmp = x_m / 1.0d0
    end if
    code = x_s * tmp
end function
x\_m = Math.abs(x);
x\_s = Math.copySign(1.0, x);
public static double code(double x_s, double x_m, double y, double z) {
	double tmp;
	if (z <= -2.55e-9) {
		tmp = x_m / 1.0;
	} else if (z <= 2.8e+35) {
		tmp = (x_m * y) / z;
	} else {
		tmp = x_m / 1.0;
	}
	return x_s * tmp;
}
x\_m = math.fabs(x)
x\_s = math.copysign(1.0, x)
def code(x_s, x_m, y, z):
	tmp = 0
	if z <= -2.55e-9:
		tmp = x_m / 1.0
	elif z <= 2.8e+35:
		tmp = (x_m * y) / z
	else:
		tmp = x_m / 1.0
	return x_s * tmp
x\_m = abs(x)
x\_s = copysign(1.0, x)
function code(x_s, x_m, y, z)
	tmp = 0.0
	if (z <= -2.55e-9)
		tmp = Float64(x_m / 1.0);
	elseif (z <= 2.8e+35)
		tmp = Float64(Float64(x_m * y) / z);
	else
		tmp = Float64(x_m / 1.0);
	end
	return Float64(x_s * tmp)
end
x\_m = abs(x);
x\_s = sign(x) * abs(1.0);
function tmp_2 = code(x_s, x_m, y, z)
	tmp = 0.0;
	if (z <= -2.55e-9)
		tmp = x_m / 1.0;
	elseif (z <= 2.8e+35)
		tmp = (x_m * y) / z;
	else
		tmp = x_m / 1.0;
	end
	tmp_2 = x_s * tmp;
end
x\_m = N[Abs[x], $MachinePrecision]
x\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_, y_, z_] := N[(x$95$s * If[LessEqual[z, -2.55e-9], N[(x$95$m / 1.0), $MachinePrecision], If[LessEqual[z, 2.8e+35], N[(N[(x$95$m * y), $MachinePrecision] / z), $MachinePrecision], N[(x$95$m / 1.0), $MachinePrecision]]]), $MachinePrecision]
\begin{array}{l}
x\_m = \left|x\right|
\\
x\_s = \mathsf{copysign}\left(1, x\right)

\\
x\_s \cdot \begin{array}{l}
\mathbf{if}\;z \leq -2.55 \cdot 10^{-9}:\\
\;\;\;\;\frac{x\_m}{1}\\

\mathbf{elif}\;z \leq 2.8 \cdot 10^{+35}:\\
\;\;\;\;\frac{x\_m \cdot y}{z}\\

\mathbf{else}:\\
\;\;\;\;\frac{x\_m}{1}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if z < -2.55000000000000009e-9 or 2.79999999999999999e35 < z

    1. Initial program 78.6%

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

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

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

        \[\leadsto \color{blue}{x \cdot \frac{y + z}{z}} \]
      4. clear-numN/A

        \[\leadsto x \cdot \color{blue}{\frac{1}{\frac{z}{y + z}}} \]
      5. un-div-invN/A

        \[\leadsto \color{blue}{\frac{x}{\frac{z}{y + z}}} \]
      6. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{x}{\frac{z}{y + z}}} \]
      7. lower-/.f6499.9

        \[\leadsto \frac{x}{\color{blue}{\frac{z}{y + z}}} \]
    4. Applied rewrites99.9%

      \[\leadsto \color{blue}{\frac{x}{\frac{z}{y + z}}} \]
    5. Taylor expanded in z around inf

      \[\leadsto \frac{x}{\color{blue}{1}} \]
    6. Step-by-step derivation
      1. Applied rewrites77.8%

        \[\leadsto \frac{x}{\color{blue}{1}} \]

      if -2.55000000000000009e-9 < z < 2.79999999999999999e35

      1. Initial program 96.5%

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

        \[\leadsto \frac{\color{blue}{x \cdot y}}{z} \]
      4. Step-by-step derivation
        1. lower-*.f6475.5

          \[\leadsto \frac{\color{blue}{x \cdot y}}{z} \]
      5. Applied rewrites75.5%

        \[\leadsto \frac{\color{blue}{x \cdot y}}{z} \]
    7. Recombined 2 regimes into one program.
    8. Add Preprocessing

    Alternative 3: 96.5% accurate, 0.8× speedup?

    \[\begin{array}{l} x\_m = \left|x\right| \\ x\_s = \mathsf{copysign}\left(1, x\right) \\ x\_s \cdot \frac{x\_m}{\frac{z}{z + y}} \end{array} \]
    x\_m = (fabs.f64 x)
    x\_s = (copysign.f64 #s(literal 1 binary64) x)
    (FPCore (x_s x_m y z) :precision binary64 (* x_s (/ x_m (/ z (+ z y)))))
    x\_m = fabs(x);
    x\_s = copysign(1.0, x);
    double code(double x_s, double x_m, double y, double z) {
    	return x_s * (x_m / (z / (z + y)));
    }
    
    x\_m = abs(x)
    x\_s = copysign(1.0d0, x)
    real(8) function code(x_s, x_m, y, z)
        real(8), intent (in) :: x_s
        real(8), intent (in) :: x_m
        real(8), intent (in) :: y
        real(8), intent (in) :: z
        code = x_s * (x_m / (z / (z + y)))
    end function
    
    x\_m = Math.abs(x);
    x\_s = Math.copySign(1.0, x);
    public static double code(double x_s, double x_m, double y, double z) {
    	return x_s * (x_m / (z / (z + y)));
    }
    
    x\_m = math.fabs(x)
    x\_s = math.copysign(1.0, x)
    def code(x_s, x_m, y, z):
    	return x_s * (x_m / (z / (z + y)))
    
    x\_m = abs(x)
    x\_s = copysign(1.0, x)
    function code(x_s, x_m, y, z)
    	return Float64(x_s * Float64(x_m / Float64(z / Float64(z + y))))
    end
    
    x\_m = abs(x);
    x\_s = sign(x) * abs(1.0);
    function tmp = code(x_s, x_m, y, z)
    	tmp = x_s * (x_m / (z / (z + y)));
    end
    
    x\_m = N[Abs[x], $MachinePrecision]
    x\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
    code[x$95$s_, x$95$m_, y_, z_] := N[(x$95$s * N[(x$95$m / N[(z / N[(z + y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
    
    \begin{array}{l}
    x\_m = \left|x\right|
    \\
    x\_s = \mathsf{copysign}\left(1, x\right)
    
    \\
    x\_s \cdot \frac{x\_m}{\frac{z}{z + y}}
    \end{array}
    
    Derivation
    1. Initial program 86.4%

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

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

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

        \[\leadsto \color{blue}{x \cdot \frac{y + z}{z}} \]
      4. clear-numN/A

        \[\leadsto x \cdot \color{blue}{\frac{1}{\frac{z}{y + z}}} \]
      5. un-div-invN/A

        \[\leadsto \color{blue}{\frac{x}{\frac{z}{y + z}}} \]
      6. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{x}{\frac{z}{y + z}}} \]
      7. lower-/.f6497.6

        \[\leadsto \frac{x}{\color{blue}{\frac{z}{y + z}}} \]
    4. Applied rewrites97.6%

      \[\leadsto \color{blue}{\frac{x}{\frac{z}{y + z}}} \]
    5. Final simplification97.6%

      \[\leadsto \frac{x}{\frac{z}{z + y}} \]
    6. Add Preprocessing

    Alternative 4: 96.2% accurate, 1.1× speedup?

    \[\begin{array}{l} x\_m = \left|x\right| \\ x\_s = \mathsf{copysign}\left(1, x\right) \\ x\_s \cdot \mathsf{fma}\left(x\_m, \frac{y}{z}, x\_m\right) \end{array} \]
    x\_m = (fabs.f64 x)
    x\_s = (copysign.f64 #s(literal 1 binary64) x)
    (FPCore (x_s x_m y z) :precision binary64 (* x_s (fma x_m (/ y z) x_m)))
    x\_m = fabs(x);
    x\_s = copysign(1.0, x);
    double code(double x_s, double x_m, double y, double z) {
    	return x_s * fma(x_m, (y / z), x_m);
    }
    
    x\_m = abs(x)
    x\_s = copysign(1.0, x)
    function code(x_s, x_m, y, z)
    	return Float64(x_s * fma(x_m, Float64(y / z), x_m))
    end
    
    x\_m = N[Abs[x], $MachinePrecision]
    x\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
    code[x$95$s_, x$95$m_, y_, z_] := N[(x$95$s * N[(x$95$m * N[(y / z), $MachinePrecision] + x$95$m), $MachinePrecision]), $MachinePrecision]
    
    \begin{array}{l}
    x\_m = \left|x\right|
    \\
    x\_s = \mathsf{copysign}\left(1, x\right)
    
    \\
    x\_s \cdot \mathsf{fma}\left(x\_m, \frac{y}{z}, x\_m\right)
    \end{array}
    
    Derivation
    1. Initial program 86.4%

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

      \[\leadsto \color{blue}{\frac{x \cdot y + x \cdot z}{z}} \]
    4. Step-by-step derivation
      1. distribute-lft-inN/A

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

        \[\leadsto \color{blue}{x \cdot \frac{y + z}{z}} \]
      3. +-commutativeN/A

        \[\leadsto x \cdot \frac{\color{blue}{z + y}}{z} \]
      4. *-lft-identityN/A

        \[\leadsto x \cdot \frac{z + \color{blue}{1 \cdot y}}{z} \]
      5. metadata-evalN/A

        \[\leadsto x \cdot \frac{z + \color{blue}{\left(\mathsf{neg}\left(-1\right)\right)} \cdot y}{z} \]
      6. cancel-sign-sub-invN/A

        \[\leadsto x \cdot \frac{\color{blue}{z - -1 \cdot y}}{z} \]
      7. div-subN/A

        \[\leadsto x \cdot \color{blue}{\left(\frac{z}{z} - \frac{-1 \cdot y}{z}\right)} \]
      8. *-inversesN/A

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

        \[\leadsto x \cdot \left(1 - \color{blue}{-1 \cdot \frac{y}{z}}\right) \]
      10. unsub-negN/A

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

        \[\leadsto x \cdot \left(1 + \left(\mathsf{neg}\left(\color{blue}{\left(\mathsf{neg}\left(\frac{y}{z}\right)\right)}\right)\right)\right) \]
      12. remove-double-negN/A

        \[\leadsto x \cdot \left(1 + \color{blue}{\frac{y}{z}}\right) \]
      13. +-commutativeN/A

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

        \[\leadsto x \cdot \left(\frac{y}{z} + \color{blue}{\left(\mathsf{neg}\left(-1\right)\right)}\right) \]
      15. sub-negN/A

        \[\leadsto x \cdot \color{blue}{\left(\frac{y}{z} - -1\right)} \]
      16. sub-negN/A

        \[\leadsto x \cdot \color{blue}{\left(\frac{y}{z} + \left(\mathsf{neg}\left(-1\right)\right)\right)} \]
      17. metadata-evalN/A

        \[\leadsto x \cdot \left(\frac{y}{z} + \color{blue}{1}\right) \]
      18. distribute-lft-outN/A

        \[\leadsto \color{blue}{x \cdot \frac{y}{z} + x \cdot 1} \]
      19. *-rgt-identityN/A

        \[\leadsto x \cdot \frac{y}{z} + \color{blue}{x} \]
      20. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(x, \frac{y}{z}, x\right)} \]
      21. lower-/.f6497.3

        \[\leadsto \mathsf{fma}\left(x, \color{blue}{\frac{y}{z}}, x\right) \]
    5. Applied rewrites97.3%

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

    Alternative 5: 50.4% accurate, 1.7× speedup?

    \[\begin{array}{l} x\_m = \left|x\right| \\ x\_s = \mathsf{copysign}\left(1, x\right) \\ x\_s \cdot \frac{x\_m}{1} \end{array} \]
    x\_m = (fabs.f64 x)
    x\_s = (copysign.f64 #s(literal 1 binary64) x)
    (FPCore (x_s x_m y z) :precision binary64 (* x_s (/ x_m 1.0)))
    x\_m = fabs(x);
    x\_s = copysign(1.0, x);
    double code(double x_s, double x_m, double y, double z) {
    	return x_s * (x_m / 1.0);
    }
    
    x\_m = abs(x)
    x\_s = copysign(1.0d0, x)
    real(8) function code(x_s, x_m, y, z)
        real(8), intent (in) :: x_s
        real(8), intent (in) :: x_m
        real(8), intent (in) :: y
        real(8), intent (in) :: z
        code = x_s * (x_m / 1.0d0)
    end function
    
    x\_m = Math.abs(x);
    x\_s = Math.copySign(1.0, x);
    public static double code(double x_s, double x_m, double y, double z) {
    	return x_s * (x_m / 1.0);
    }
    
    x\_m = math.fabs(x)
    x\_s = math.copysign(1.0, x)
    def code(x_s, x_m, y, z):
    	return x_s * (x_m / 1.0)
    
    x\_m = abs(x)
    x\_s = copysign(1.0, x)
    function code(x_s, x_m, y, z)
    	return Float64(x_s * Float64(x_m / 1.0))
    end
    
    x\_m = abs(x);
    x\_s = sign(x) * abs(1.0);
    function tmp = code(x_s, x_m, y, z)
    	tmp = x_s * (x_m / 1.0);
    end
    
    x\_m = N[Abs[x], $MachinePrecision]
    x\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
    code[x$95$s_, x$95$m_, y_, z_] := N[(x$95$s * N[(x$95$m / 1.0), $MachinePrecision]), $MachinePrecision]
    
    \begin{array}{l}
    x\_m = \left|x\right|
    \\
    x\_s = \mathsf{copysign}\left(1, x\right)
    
    \\
    x\_s \cdot \frac{x\_m}{1}
    \end{array}
    
    Derivation
    1. Initial program 86.4%

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

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

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

        \[\leadsto \color{blue}{x \cdot \frac{y + z}{z}} \]
      4. clear-numN/A

        \[\leadsto x \cdot \color{blue}{\frac{1}{\frac{z}{y + z}}} \]
      5. un-div-invN/A

        \[\leadsto \color{blue}{\frac{x}{\frac{z}{y + z}}} \]
      6. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{x}{\frac{z}{y + z}}} \]
      7. lower-/.f6497.6

        \[\leadsto \frac{x}{\color{blue}{\frac{z}{y + z}}} \]
    4. Applied rewrites97.6%

      \[\leadsto \color{blue}{\frac{x}{\frac{z}{y + z}}} \]
    5. Taylor expanded in z around inf

      \[\leadsto \frac{x}{\color{blue}{1}} \]
    6. Step-by-step derivation
      1. Applied rewrites53.7%

        \[\leadsto \frac{x}{\color{blue}{1}} \]
      2. Add Preprocessing

      Developer Target 1: 96.5% accurate, 0.8× speedup?

      \[\begin{array}{l} \\ \frac{x}{\frac{z}{y + z}} \end{array} \]
      (FPCore (x y z) :precision binary64 (/ x (/ z (+ y z))))
      double code(double x, double y, double z) {
      	return x / (z / (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 = x / (z / (y + z))
      end function
      
      public static double code(double x, double y, double z) {
      	return x / (z / (y + z));
      }
      
      def code(x, y, z):
      	return x / (z / (y + z))
      
      function code(x, y, z)
      	return Float64(x / Float64(z / Float64(y + z)))
      end
      
      function tmp = code(x, y, z)
      	tmp = x / (z / (y + z));
      end
      
      code[x_, y_, z_] := N[(x / N[(z / N[(y + z), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \frac{x}{\frac{z}{y + z}}
      \end{array}
      

      Reproduce

      ?
      herbie shell --seed 2024228 
      (FPCore (x y z)
        :name "Numeric.SpecFunctions:choose from math-functions-0.1.5.2"
        :precision binary64
      
        :alt
        (! :herbie-platform default (/ x (/ z (+ y z))))
      
        (/ (* x (+ y z)) z))