Bouland and Aaronson, Equation (26)

Percentage Accurate: 99.9% → 99.9%
Time: 7.0s
Alternatives: 8
Speedup: 1.0×

Specification

?
\[\begin{array}{l} \\ \left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(b \cdot b\right)\right) - 1 \end{array} \]
(FPCore (a b)
 :precision binary64
 (- (+ (pow (+ (* a a) (* b b)) 2.0) (* 4.0 (* b b))) 1.0))
double code(double a, double b) {
	return (pow(((a * a) + (b * b)), 2.0) + (4.0 * (b * b))) - 1.0;
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    code = ((((a * a) + (b * b)) ** 2.0d0) + (4.0d0 * (b * b))) - 1.0d0
end function
public static double code(double a, double b) {
	return (Math.pow(((a * a) + (b * b)), 2.0) + (4.0 * (b * b))) - 1.0;
}
def code(a, b):
	return (math.pow(((a * a) + (b * b)), 2.0) + (4.0 * (b * b))) - 1.0
function code(a, b)
	return Float64(Float64((Float64(Float64(a * a) + Float64(b * b)) ^ 2.0) + Float64(4.0 * Float64(b * b))) - 1.0)
end
function tmp = code(a, b)
	tmp = ((((a * a) + (b * b)) ^ 2.0) + (4.0 * (b * b))) - 1.0;
end
code[a_, b_] := N[(N[(N[Power[N[(N[(a * a), $MachinePrecision] + N[(b * b), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision] + N[(4.0 * N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - 1.0), $MachinePrecision]
\begin{array}{l}

\\
\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(b \cdot b\right)\right) - 1
\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 8 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: 99.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(b \cdot b\right)\right) - 1 \end{array} \]
(FPCore (a b)
 :precision binary64
 (- (+ (pow (+ (* a a) (* b b)) 2.0) (* 4.0 (* b b))) 1.0))
double code(double a, double b) {
	return (pow(((a * a) + (b * b)), 2.0) + (4.0 * (b * b))) - 1.0;
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    code = ((((a * a) + (b * b)) ** 2.0d0) + (4.0d0 * (b * b))) - 1.0d0
end function
public static double code(double a, double b) {
	return (Math.pow(((a * a) + (b * b)), 2.0) + (4.0 * (b * b))) - 1.0;
}
def code(a, b):
	return (math.pow(((a * a) + (b * b)), 2.0) + (4.0 * (b * b))) - 1.0
function code(a, b)
	return Float64(Float64((Float64(Float64(a * a) + Float64(b * b)) ^ 2.0) + Float64(4.0 * Float64(b * b))) - 1.0)
end
function tmp = code(a, b)
	tmp = ((((a * a) + (b * b)) ^ 2.0) + (4.0 * (b * b))) - 1.0;
end
code[a_, b_] := N[(N[(N[Power[N[(N[(a * a), $MachinePrecision] + N[(b * b), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision] + N[(4.0 * N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - 1.0), $MachinePrecision]
\begin{array}{l}

\\
\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(b \cdot b\right)\right) - 1
\end{array}

Alternative 1: 99.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(b \cdot b\right)\right) - 1 \end{array} \]
(FPCore (a b)
 :precision binary64
 (- (+ (pow (+ (* a a) (* b b)) 2.0) (* 4.0 (* b b))) 1.0))
double code(double a, double b) {
	return (pow(((a * a) + (b * b)), 2.0) + (4.0 * (b * b))) - 1.0;
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    code = ((((a * a) + (b * b)) ** 2.0d0) + (4.0d0 * (b * b))) - 1.0d0
end function
public static double code(double a, double b) {
	return (Math.pow(((a * a) + (b * b)), 2.0) + (4.0 * (b * b))) - 1.0;
}
def code(a, b):
	return (math.pow(((a * a) + (b * b)), 2.0) + (4.0 * (b * b))) - 1.0
function code(a, b)
	return Float64(Float64((Float64(Float64(a * a) + Float64(b * b)) ^ 2.0) + Float64(4.0 * Float64(b * b))) - 1.0)
end
function tmp = code(a, b)
	tmp = ((((a * a) + (b * b)) ^ 2.0) + (4.0 * (b * b))) - 1.0;
end
code[a_, b_] := N[(N[(N[Power[N[(N[(a * a), $MachinePrecision] + N[(b * b), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision] + N[(4.0 * N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - 1.0), $MachinePrecision]
\begin{array}{l}

\\
\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(b \cdot b\right)\right) - 1
\end{array}
Derivation
  1. Initial program 99.9%

    \[\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
  2. Add Preprocessing
  3. Add Preprocessing

Alternative 2: 83.8% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq 0.00106:\\ \;\;\;\;\mathsf{fma}\left(b \cdot b, 4, {b}^{4}\right) - 1\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(b \cdot b, 4, \left(\mathsf{fma}\left(b \cdot b, 2, a \cdot a\right) \cdot a\right) \cdot a - 1\right)\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (<= a 0.00106)
   (- (fma (* b b) 4.0 (pow b 4.0)) 1.0)
   (fma (* b b) 4.0 (- (* (* (fma (* b b) 2.0 (* a a)) a) a) 1.0))))
double code(double a, double b) {
	double tmp;
	if (a <= 0.00106) {
		tmp = fma((b * b), 4.0, pow(b, 4.0)) - 1.0;
	} else {
		tmp = fma((b * b), 4.0, (((fma((b * b), 2.0, (a * a)) * a) * a) - 1.0));
	}
	return tmp;
}
function code(a, b)
	tmp = 0.0
	if (a <= 0.00106)
		tmp = Float64(fma(Float64(b * b), 4.0, (b ^ 4.0)) - 1.0);
	else
		tmp = fma(Float64(b * b), 4.0, Float64(Float64(Float64(fma(Float64(b * b), 2.0, Float64(a * a)) * a) * a) - 1.0));
	end
	return tmp
end
code[a_, b_] := If[LessEqual[a, 0.00106], N[(N[(N[(b * b), $MachinePrecision] * 4.0 + N[Power[b, 4.0], $MachinePrecision]), $MachinePrecision] - 1.0), $MachinePrecision], N[(N[(b * b), $MachinePrecision] * 4.0 + N[(N[(N[(N[(N[(b * b), $MachinePrecision] * 2.0 + N[(a * a), $MachinePrecision]), $MachinePrecision] * a), $MachinePrecision] * a), $MachinePrecision] - 1.0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;a \leq 0.00106:\\
\;\;\;\;\mathsf{fma}\left(b \cdot b, 4, {b}^{4}\right) - 1\\

\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(b \cdot b, 4, \left(\mathsf{fma}\left(b \cdot b, 2, a \cdot a\right) \cdot a\right) \cdot a - 1\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if a < 0.00105999999999999996

    1. Initial program 99.9%

      \[\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
    2. Add Preprocessing
    3. Taylor expanded in a around 0

      \[\leadsto \color{blue}{\left(4 \cdot {b}^{2} + {b}^{4}\right)} - 1 \]
    4. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \left(\color{blue}{{b}^{2} \cdot 4} + {b}^{4}\right) - 1 \]
      2. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left({b}^{2}, 4, {b}^{4}\right)} - 1 \]
      3. unpow2N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{b \cdot b}, 4, {b}^{4}\right) - 1 \]
      4. lower-*.f64N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{b \cdot b}, 4, {b}^{4}\right) - 1 \]
      5. lower-pow.f6477.3

        \[\leadsto \mathsf{fma}\left(b \cdot b, 4, \color{blue}{{b}^{4}}\right) - 1 \]
    5. Applied rewrites77.3%

      \[\leadsto \color{blue}{\mathsf{fma}\left(b \cdot b, 4, {b}^{4}\right)} - 1 \]

    if 0.00105999999999999996 < a

    1. Initial program 99.9%

      \[\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
    2. Add Preprocessing
    3. Taylor expanded in b around 0

      \[\leadsto \left(\color{blue}{\left(2 \cdot \left({a}^{2} \cdot {b}^{2}\right) + {a}^{4}\right)} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
    4. Step-by-step derivation
      1. metadata-evalN/A

        \[\leadsto \left(\left(2 \cdot \left({a}^{2} \cdot {b}^{2}\right) + {a}^{\color{blue}{\left(2 \cdot 2\right)}}\right) + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
      2. pow-sqrN/A

        \[\leadsto \left(\left(2 \cdot \left({a}^{2} \cdot {b}^{2}\right) + \color{blue}{{a}^{2} \cdot {a}^{2}}\right) + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
      3. count-2-revN/A

        \[\leadsto \left(\left(\color{blue}{\left({a}^{2} \cdot {b}^{2} + {a}^{2} \cdot {b}^{2}\right)} + {a}^{2} \cdot {a}^{2}\right) + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
      4. distribute-lft-inN/A

        \[\leadsto \left(\left(\color{blue}{{a}^{2} \cdot \left({b}^{2} + {b}^{2}\right)} + {a}^{2} \cdot {a}^{2}\right) + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
      5. count-2-revN/A

        \[\leadsto \left(\left({a}^{2} \cdot \color{blue}{\left(2 \cdot {b}^{2}\right)} + {a}^{2} \cdot {a}^{2}\right) + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
      6. distribute-lft-inN/A

        \[\leadsto \left(\color{blue}{{a}^{2} \cdot \left(2 \cdot {b}^{2} + {a}^{2}\right)} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
      7. *-commutativeN/A

        \[\leadsto \left(\color{blue}{\left(2 \cdot {b}^{2} + {a}^{2}\right) \cdot {a}^{2}} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
      8. unpow2N/A

        \[\leadsto \left(\left(2 \cdot {b}^{2} + {a}^{2}\right) \cdot \color{blue}{\left(a \cdot a\right)} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
      9. associate-*r*N/A

        \[\leadsto \left(\color{blue}{\left(\left(2 \cdot {b}^{2} + {a}^{2}\right) \cdot a\right) \cdot a} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
      10. lower-*.f64N/A

        \[\leadsto \left(\color{blue}{\left(\left(2 \cdot {b}^{2} + {a}^{2}\right) \cdot a\right) \cdot a} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
      11. lower-*.f64N/A

        \[\leadsto \left(\color{blue}{\left(\left(2 \cdot {b}^{2} + {a}^{2}\right) \cdot a\right)} \cdot a + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
      12. *-commutativeN/A

        \[\leadsto \left(\left(\left(\color{blue}{{b}^{2} \cdot 2} + {a}^{2}\right) \cdot a\right) \cdot a + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
      13. lower-fma.f64N/A

        \[\leadsto \left(\left(\color{blue}{\mathsf{fma}\left({b}^{2}, 2, {a}^{2}\right)} \cdot a\right) \cdot a + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
      14. unpow2N/A

        \[\leadsto \left(\left(\mathsf{fma}\left(\color{blue}{b \cdot b}, 2, {a}^{2}\right) \cdot a\right) \cdot a + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
      15. lower-*.f64N/A

        \[\leadsto \left(\left(\mathsf{fma}\left(\color{blue}{b \cdot b}, 2, {a}^{2}\right) \cdot a\right) \cdot a + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
      16. unpow2N/A

        \[\leadsto \left(\left(\mathsf{fma}\left(b \cdot b, 2, \color{blue}{a \cdot a}\right) \cdot a\right) \cdot a + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
      17. lower-*.f6498.3

        \[\leadsto \left(\left(\mathsf{fma}\left(b \cdot b, 2, \color{blue}{a \cdot a}\right) \cdot a\right) \cdot a + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
    5. Applied rewrites98.3%

      \[\leadsto \left(\color{blue}{\left(\mathsf{fma}\left(b \cdot b, 2, a \cdot a\right) \cdot a\right) \cdot a} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
    6. Step-by-step derivation
      1. lift--.f64N/A

        \[\leadsto \color{blue}{\left(\left(\mathsf{fma}\left(b \cdot b, 2, a \cdot a\right) \cdot a\right) \cdot a + 4 \cdot \left(b \cdot b\right)\right) - 1} \]
      2. lift-+.f64N/A

        \[\leadsto \color{blue}{\left(\left(\mathsf{fma}\left(b \cdot b, 2, a \cdot a\right) \cdot a\right) \cdot a + 4 \cdot \left(b \cdot b\right)\right)} - 1 \]
      3. +-commutativeN/A

        \[\leadsto \color{blue}{\left(4 \cdot \left(b \cdot b\right) + \left(\mathsf{fma}\left(b \cdot b, 2, a \cdot a\right) \cdot a\right) \cdot a\right)} - 1 \]
      4. associate--l+N/A

        \[\leadsto \color{blue}{4 \cdot \left(b \cdot b\right) + \left(\left(\mathsf{fma}\left(b \cdot b, 2, a \cdot a\right) \cdot a\right) \cdot a - 1\right)} \]
      5. lift-*.f64N/A

        \[\leadsto \color{blue}{4 \cdot \left(b \cdot b\right)} + \left(\left(\mathsf{fma}\left(b \cdot b, 2, a \cdot a\right) \cdot a\right) \cdot a - 1\right) \]
      6. *-commutativeN/A

        \[\leadsto \color{blue}{\left(b \cdot b\right) \cdot 4} + \left(\left(\mathsf{fma}\left(b \cdot b, 2, a \cdot a\right) \cdot a\right) \cdot a - 1\right) \]
      7. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(b \cdot b, 4, \left(\mathsf{fma}\left(b \cdot b, 2, a \cdot a\right) \cdot a\right) \cdot a - 1\right)} \]
      8. lower--.f6498.3

        \[\leadsto \mathsf{fma}\left(b \cdot b, 4, \color{blue}{\left(\mathsf{fma}\left(b \cdot b, 2, a \cdot a\right) \cdot a\right) \cdot a - 1}\right) \]
    7. Applied rewrites98.3%

      \[\leadsto \color{blue}{\mathsf{fma}\left(b \cdot b, 4, \left(\mathsf{fma}\left(b \cdot b, 2, a \cdot a\right) \cdot a\right) \cdot a - 1\right)} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 3: 83.7% accurate, 2.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq 0.00106:\\ \;\;\;\;\left(b \cdot b\right) \cdot \mathsf{fma}\left(b, b, 4\right) - 1\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(b \cdot b, 4, \left(\mathsf{fma}\left(b \cdot b, 2, a \cdot a\right) \cdot a\right) \cdot a - 1\right)\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (<= a 0.00106)
   (- (* (* b b) (fma b b 4.0)) 1.0)
   (fma (* b b) 4.0 (- (* (* (fma (* b b) 2.0 (* a a)) a) a) 1.0))))
double code(double a, double b) {
	double tmp;
	if (a <= 0.00106) {
		tmp = ((b * b) * fma(b, b, 4.0)) - 1.0;
	} else {
		tmp = fma((b * b), 4.0, (((fma((b * b), 2.0, (a * a)) * a) * a) - 1.0));
	}
	return tmp;
}
function code(a, b)
	tmp = 0.0
	if (a <= 0.00106)
		tmp = Float64(Float64(Float64(b * b) * fma(b, b, 4.0)) - 1.0);
	else
		tmp = fma(Float64(b * b), 4.0, Float64(Float64(Float64(fma(Float64(b * b), 2.0, Float64(a * a)) * a) * a) - 1.0));
	end
	return tmp
end
code[a_, b_] := If[LessEqual[a, 0.00106], N[(N[(N[(b * b), $MachinePrecision] * N[(b * b + 4.0), $MachinePrecision]), $MachinePrecision] - 1.0), $MachinePrecision], N[(N[(b * b), $MachinePrecision] * 4.0 + N[(N[(N[(N[(N[(b * b), $MachinePrecision] * 2.0 + N[(a * a), $MachinePrecision]), $MachinePrecision] * a), $MachinePrecision] * a), $MachinePrecision] - 1.0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;a \leq 0.00106:\\
\;\;\;\;\left(b \cdot b\right) \cdot \mathsf{fma}\left(b, b, 4\right) - 1\\

\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(b \cdot b, 4, \left(\mathsf{fma}\left(b \cdot b, 2, a \cdot a\right) \cdot a\right) \cdot a - 1\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if a < 0.00105999999999999996

    1. Initial program 99.9%

      \[\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
    2. Add Preprocessing
    3. Taylor expanded in a around 0

      \[\leadsto \color{blue}{\left(4 \cdot {b}^{2} + {b}^{4}\right)} - 1 \]
    4. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \left(\color{blue}{{b}^{2} \cdot 4} + {b}^{4}\right) - 1 \]
      2. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left({b}^{2}, 4, {b}^{4}\right)} - 1 \]
      3. unpow2N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{b \cdot b}, 4, {b}^{4}\right) - 1 \]
      4. lower-*.f64N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{b \cdot b}, 4, {b}^{4}\right) - 1 \]
      5. lower-pow.f6477.3

        \[\leadsto \mathsf{fma}\left(b \cdot b, 4, \color{blue}{{b}^{4}}\right) - 1 \]
    5. Applied rewrites77.3%

      \[\leadsto \color{blue}{\mathsf{fma}\left(b \cdot b, 4, {b}^{4}\right)} - 1 \]
    6. Step-by-step derivation
      1. Applied rewrites77.3%

        \[\leadsto \left(b \cdot b\right) \cdot \color{blue}{\mathsf{fma}\left(b, b, 4\right)} - 1 \]

      if 0.00105999999999999996 < a

      1. Initial program 99.9%

        \[\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
      2. Add Preprocessing
      3. Taylor expanded in b around 0

        \[\leadsto \left(\color{blue}{\left(2 \cdot \left({a}^{2} \cdot {b}^{2}\right) + {a}^{4}\right)} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
      4. Step-by-step derivation
        1. metadata-evalN/A

          \[\leadsto \left(\left(2 \cdot \left({a}^{2} \cdot {b}^{2}\right) + {a}^{\color{blue}{\left(2 \cdot 2\right)}}\right) + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
        2. pow-sqrN/A

          \[\leadsto \left(\left(2 \cdot \left({a}^{2} \cdot {b}^{2}\right) + \color{blue}{{a}^{2} \cdot {a}^{2}}\right) + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
        3. count-2-revN/A

          \[\leadsto \left(\left(\color{blue}{\left({a}^{2} \cdot {b}^{2} + {a}^{2} \cdot {b}^{2}\right)} + {a}^{2} \cdot {a}^{2}\right) + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
        4. distribute-lft-inN/A

          \[\leadsto \left(\left(\color{blue}{{a}^{2} \cdot \left({b}^{2} + {b}^{2}\right)} + {a}^{2} \cdot {a}^{2}\right) + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
        5. count-2-revN/A

          \[\leadsto \left(\left({a}^{2} \cdot \color{blue}{\left(2 \cdot {b}^{2}\right)} + {a}^{2} \cdot {a}^{2}\right) + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
        6. distribute-lft-inN/A

          \[\leadsto \left(\color{blue}{{a}^{2} \cdot \left(2 \cdot {b}^{2} + {a}^{2}\right)} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
        7. *-commutativeN/A

          \[\leadsto \left(\color{blue}{\left(2 \cdot {b}^{2} + {a}^{2}\right) \cdot {a}^{2}} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
        8. unpow2N/A

          \[\leadsto \left(\left(2 \cdot {b}^{2} + {a}^{2}\right) \cdot \color{blue}{\left(a \cdot a\right)} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
        9. associate-*r*N/A

          \[\leadsto \left(\color{blue}{\left(\left(2 \cdot {b}^{2} + {a}^{2}\right) \cdot a\right) \cdot a} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
        10. lower-*.f64N/A

          \[\leadsto \left(\color{blue}{\left(\left(2 \cdot {b}^{2} + {a}^{2}\right) \cdot a\right) \cdot a} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
        11. lower-*.f64N/A

          \[\leadsto \left(\color{blue}{\left(\left(2 \cdot {b}^{2} + {a}^{2}\right) \cdot a\right)} \cdot a + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
        12. *-commutativeN/A

          \[\leadsto \left(\left(\left(\color{blue}{{b}^{2} \cdot 2} + {a}^{2}\right) \cdot a\right) \cdot a + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
        13. lower-fma.f64N/A

          \[\leadsto \left(\left(\color{blue}{\mathsf{fma}\left({b}^{2}, 2, {a}^{2}\right)} \cdot a\right) \cdot a + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
        14. unpow2N/A

          \[\leadsto \left(\left(\mathsf{fma}\left(\color{blue}{b \cdot b}, 2, {a}^{2}\right) \cdot a\right) \cdot a + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
        15. lower-*.f64N/A

          \[\leadsto \left(\left(\mathsf{fma}\left(\color{blue}{b \cdot b}, 2, {a}^{2}\right) \cdot a\right) \cdot a + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
        16. unpow2N/A

          \[\leadsto \left(\left(\mathsf{fma}\left(b \cdot b, 2, \color{blue}{a \cdot a}\right) \cdot a\right) \cdot a + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
        17. lower-*.f6498.3

          \[\leadsto \left(\left(\mathsf{fma}\left(b \cdot b, 2, \color{blue}{a \cdot a}\right) \cdot a\right) \cdot a + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
      5. Applied rewrites98.3%

        \[\leadsto \left(\color{blue}{\left(\mathsf{fma}\left(b \cdot b, 2, a \cdot a\right) \cdot a\right) \cdot a} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
      6. Step-by-step derivation
        1. lift--.f64N/A

          \[\leadsto \color{blue}{\left(\left(\mathsf{fma}\left(b \cdot b, 2, a \cdot a\right) \cdot a\right) \cdot a + 4 \cdot \left(b \cdot b\right)\right) - 1} \]
        2. lift-+.f64N/A

          \[\leadsto \color{blue}{\left(\left(\mathsf{fma}\left(b \cdot b, 2, a \cdot a\right) \cdot a\right) \cdot a + 4 \cdot \left(b \cdot b\right)\right)} - 1 \]
        3. +-commutativeN/A

          \[\leadsto \color{blue}{\left(4 \cdot \left(b \cdot b\right) + \left(\mathsf{fma}\left(b \cdot b, 2, a \cdot a\right) \cdot a\right) \cdot a\right)} - 1 \]
        4. associate--l+N/A

          \[\leadsto \color{blue}{4 \cdot \left(b \cdot b\right) + \left(\left(\mathsf{fma}\left(b \cdot b, 2, a \cdot a\right) \cdot a\right) \cdot a - 1\right)} \]
        5. lift-*.f64N/A

          \[\leadsto \color{blue}{4 \cdot \left(b \cdot b\right)} + \left(\left(\mathsf{fma}\left(b \cdot b, 2, a \cdot a\right) \cdot a\right) \cdot a - 1\right) \]
        6. *-commutativeN/A

          \[\leadsto \color{blue}{\left(b \cdot b\right) \cdot 4} + \left(\left(\mathsf{fma}\left(b \cdot b, 2, a \cdot a\right) \cdot a\right) \cdot a - 1\right) \]
        7. lower-fma.f64N/A

          \[\leadsto \color{blue}{\mathsf{fma}\left(b \cdot b, 4, \left(\mathsf{fma}\left(b \cdot b, 2, a \cdot a\right) \cdot a\right) \cdot a - 1\right)} \]
        8. lower--.f6498.3

          \[\leadsto \mathsf{fma}\left(b \cdot b, 4, \color{blue}{\left(\mathsf{fma}\left(b \cdot b, 2, a \cdot a\right) \cdot a\right) \cdot a - 1}\right) \]
      7. Applied rewrites98.3%

        \[\leadsto \color{blue}{\mathsf{fma}\left(b \cdot b, 4, \left(\mathsf{fma}\left(b \cdot b, 2, a \cdot a\right) \cdot a\right) \cdot a - 1\right)} \]
    7. Recombined 2 regimes into one program.
    8. Add Preprocessing

    Alternative 4: 83.7% accurate, 3.5× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq 8.6 \cdot 10^{-5}:\\ \;\;\;\;\left(a \cdot a\right) \cdot \left(a \cdot a\right) - 1\\ \mathbf{else}:\\ \;\;\;\;\left(\mathsf{fma}\left(b, b, \mathsf{fma}\left(a \cdot a, 2, 4\right)\right) \cdot b\right) \cdot b - 1\\ \end{array} \end{array} \]
    (FPCore (a b)
     :precision binary64
     (if (<= b 8.6e-5)
       (- (* (* a a) (* a a)) 1.0)
       (- (* (* (fma b b (fma (* a a) 2.0 4.0)) b) b) 1.0)))
    double code(double a, double b) {
    	double tmp;
    	if (b <= 8.6e-5) {
    		tmp = ((a * a) * (a * a)) - 1.0;
    	} else {
    		tmp = ((fma(b, b, fma((a * a), 2.0, 4.0)) * b) * b) - 1.0;
    	}
    	return tmp;
    }
    
    function code(a, b)
    	tmp = 0.0
    	if (b <= 8.6e-5)
    		tmp = Float64(Float64(Float64(a * a) * Float64(a * a)) - 1.0);
    	else
    		tmp = Float64(Float64(Float64(fma(b, b, fma(Float64(a * a), 2.0, 4.0)) * b) * b) - 1.0);
    	end
    	return tmp
    end
    
    code[a_, b_] := If[LessEqual[b, 8.6e-5], N[(N[(N[(a * a), $MachinePrecision] * N[(a * a), $MachinePrecision]), $MachinePrecision] - 1.0), $MachinePrecision], N[(N[(N[(N[(b * b + N[(N[(a * a), $MachinePrecision] * 2.0 + 4.0), $MachinePrecision]), $MachinePrecision] * b), $MachinePrecision] * b), $MachinePrecision] - 1.0), $MachinePrecision]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;b \leq 8.6 \cdot 10^{-5}:\\
    \;\;\;\;\left(a \cdot a\right) \cdot \left(a \cdot a\right) - 1\\
    
    \mathbf{else}:\\
    \;\;\;\;\left(\mathsf{fma}\left(b, b, \mathsf{fma}\left(a \cdot a, 2, 4\right)\right) \cdot b\right) \cdot b - 1\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if b < 8.6000000000000003e-5

      1. Initial program 99.9%

        \[\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
      2. Add Preprocessing
      3. Taylor expanded in a around inf

        \[\leadsto \color{blue}{{a}^{4}} - 1 \]
      4. Step-by-step derivation
        1. lower-pow.f6477.3

          \[\leadsto \color{blue}{{a}^{4}} - 1 \]
      5. Applied rewrites77.3%

        \[\leadsto \color{blue}{{a}^{4}} - 1 \]
      6. Step-by-step derivation
        1. Applied rewrites77.2%

          \[\leadsto \left(a \cdot a\right) \cdot \color{blue}{\left(a \cdot a\right)} - 1 \]

        if 8.6000000000000003e-5 < b

        1. Initial program 99.9%

          \[\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
        2. Add Preprocessing
        3. Taylor expanded in a around 0

          \[\leadsto \color{blue}{\left(2 \cdot \left({a}^{2} \cdot {b}^{2}\right) + \left(4 \cdot {b}^{2} + {b}^{4}\right)\right)} - 1 \]
        4. Step-by-step derivation
          1. associate-+r+N/A

            \[\leadsto \color{blue}{\left(\left(2 \cdot \left({a}^{2} \cdot {b}^{2}\right) + 4 \cdot {b}^{2}\right) + {b}^{4}\right)} - 1 \]
          2. associate-*r*N/A

            \[\leadsto \left(\left(\color{blue}{\left(2 \cdot {a}^{2}\right) \cdot {b}^{2}} + 4 \cdot {b}^{2}\right) + {b}^{4}\right) - 1 \]
          3. distribute-rgt-inN/A

            \[\leadsto \left(\color{blue}{{b}^{2} \cdot \left(2 \cdot {a}^{2} + 4\right)} + {b}^{4}\right) - 1 \]
          4. +-commutativeN/A

            \[\leadsto \left({b}^{2} \cdot \color{blue}{\left(4 + 2 \cdot {a}^{2}\right)} + {b}^{4}\right) - 1 \]
          5. metadata-evalN/A

            \[\leadsto \left({b}^{2} \cdot \left(4 + 2 \cdot {a}^{2}\right) + {b}^{\color{blue}{\left(2 \cdot 2\right)}}\right) - 1 \]
          6. pow-sqrN/A

            \[\leadsto \left({b}^{2} \cdot \left(4 + 2 \cdot {a}^{2}\right) + \color{blue}{{b}^{2} \cdot {b}^{2}}\right) - 1 \]
          7. distribute-lft-inN/A

            \[\leadsto \color{blue}{{b}^{2} \cdot \left(\left(4 + 2 \cdot {a}^{2}\right) + {b}^{2}\right)} - 1 \]
          8. associate-+r+N/A

            \[\leadsto {b}^{2} \cdot \color{blue}{\left(4 + \left(2 \cdot {a}^{2} + {b}^{2}\right)\right)} - 1 \]
          9. *-commutativeN/A

            \[\leadsto \color{blue}{\left(4 + \left(2 \cdot {a}^{2} + {b}^{2}\right)\right) \cdot {b}^{2}} - 1 \]
          10. unpow2N/A

            \[\leadsto \left(4 + \left(2 \cdot {a}^{2} + {b}^{2}\right)\right) \cdot \color{blue}{\left(b \cdot b\right)} - 1 \]
          11. associate-*r*N/A

            \[\leadsto \color{blue}{\left(\left(4 + \left(2 \cdot {a}^{2} + {b}^{2}\right)\right) \cdot b\right) \cdot b} - 1 \]
          12. lower-*.f64N/A

            \[\leadsto \color{blue}{\left(\left(4 + \left(2 \cdot {a}^{2} + {b}^{2}\right)\right) \cdot b\right) \cdot b} - 1 \]
        5. Applied rewrites99.9%

          \[\leadsto \color{blue}{\left(\mathsf{fma}\left(b, b, \mathsf{fma}\left(a \cdot a, 2, 4\right)\right) \cdot b\right) \cdot b} - 1 \]
      7. Recombined 2 regimes into one program.
      8. Add Preprocessing

      Alternative 5: 81.8% accurate, 5.0× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq 2.5 \cdot 10^{+21}:\\ \;\;\;\;\left(b \cdot b\right) \cdot \mathsf{fma}\left(b, b, 4\right) - 1\\ \mathbf{else}:\\ \;\;\;\;\left(a \cdot a\right) \cdot \left(a \cdot a\right) - 1\\ \end{array} \end{array} \]
      (FPCore (a b)
       :precision binary64
       (if (<= a 2.5e+21)
         (- (* (* b b) (fma b b 4.0)) 1.0)
         (- (* (* a a) (* a a)) 1.0)))
      double code(double a, double b) {
      	double tmp;
      	if (a <= 2.5e+21) {
      		tmp = ((b * b) * fma(b, b, 4.0)) - 1.0;
      	} else {
      		tmp = ((a * a) * (a * a)) - 1.0;
      	}
      	return tmp;
      }
      
      function code(a, b)
      	tmp = 0.0
      	if (a <= 2.5e+21)
      		tmp = Float64(Float64(Float64(b * b) * fma(b, b, 4.0)) - 1.0);
      	else
      		tmp = Float64(Float64(Float64(a * a) * Float64(a * a)) - 1.0);
      	end
      	return tmp
      end
      
      code[a_, b_] := If[LessEqual[a, 2.5e+21], N[(N[(N[(b * b), $MachinePrecision] * N[(b * b + 4.0), $MachinePrecision]), $MachinePrecision] - 1.0), $MachinePrecision], N[(N[(N[(a * a), $MachinePrecision] * N[(a * a), $MachinePrecision]), $MachinePrecision] - 1.0), $MachinePrecision]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      \mathbf{if}\;a \leq 2.5 \cdot 10^{+21}:\\
      \;\;\;\;\left(b \cdot b\right) \cdot \mathsf{fma}\left(b, b, 4\right) - 1\\
      
      \mathbf{else}:\\
      \;\;\;\;\left(a \cdot a\right) \cdot \left(a \cdot a\right) - 1\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if a < 2.5e21

        1. Initial program 99.9%

          \[\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
        2. Add Preprocessing
        3. Taylor expanded in a around 0

          \[\leadsto \color{blue}{\left(4 \cdot {b}^{2} + {b}^{4}\right)} - 1 \]
        4. Step-by-step derivation
          1. *-commutativeN/A

            \[\leadsto \left(\color{blue}{{b}^{2} \cdot 4} + {b}^{4}\right) - 1 \]
          2. lower-fma.f64N/A

            \[\leadsto \color{blue}{\mathsf{fma}\left({b}^{2}, 4, {b}^{4}\right)} - 1 \]
          3. unpow2N/A

            \[\leadsto \mathsf{fma}\left(\color{blue}{b \cdot b}, 4, {b}^{4}\right) - 1 \]
          4. lower-*.f64N/A

            \[\leadsto \mathsf{fma}\left(\color{blue}{b \cdot b}, 4, {b}^{4}\right) - 1 \]
          5. lower-pow.f6477.3

            \[\leadsto \mathsf{fma}\left(b \cdot b, 4, \color{blue}{{b}^{4}}\right) - 1 \]
        5. Applied rewrites77.3%

          \[\leadsto \color{blue}{\mathsf{fma}\left(b \cdot b, 4, {b}^{4}\right)} - 1 \]
        6. Step-by-step derivation
          1. Applied rewrites77.3%

            \[\leadsto \left(b \cdot b\right) \cdot \color{blue}{\mathsf{fma}\left(b, b, 4\right)} - 1 \]

          if 2.5e21 < a

          1. Initial program 99.9%

            \[\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
          2. Add Preprocessing
          3. Taylor expanded in a around inf

            \[\leadsto \color{blue}{{a}^{4}} - 1 \]
          4. Step-by-step derivation
            1. lower-pow.f64100.0

              \[\leadsto \color{blue}{{a}^{4}} - 1 \]
          5. Applied rewrites100.0%

            \[\leadsto \color{blue}{{a}^{4}} - 1 \]
          6. Step-by-step derivation
            1. Applied rewrites99.9%

              \[\leadsto \left(a \cdot a\right) \cdot \color{blue}{\left(a \cdot a\right)} - 1 \]
          7. Recombined 2 regimes into one program.
          8. Add Preprocessing

          Alternative 6: 81.8% accurate, 5.0× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq 2.5 \cdot 10^{+21}:\\ \;\;\;\;\left(\mathsf{fma}\left(b, b, 4\right) \cdot b\right) \cdot b - 1\\ \mathbf{else}:\\ \;\;\;\;\left(a \cdot a\right) \cdot \left(a \cdot a\right) - 1\\ \end{array} \end{array} \]
          (FPCore (a b)
           :precision binary64
           (if (<= a 2.5e+21)
             (- (* (* (fma b b 4.0) b) b) 1.0)
             (- (* (* a a) (* a a)) 1.0)))
          double code(double a, double b) {
          	double tmp;
          	if (a <= 2.5e+21) {
          		tmp = ((fma(b, b, 4.0) * b) * b) - 1.0;
          	} else {
          		tmp = ((a * a) * (a * a)) - 1.0;
          	}
          	return tmp;
          }
          
          function code(a, b)
          	tmp = 0.0
          	if (a <= 2.5e+21)
          		tmp = Float64(Float64(Float64(fma(b, b, 4.0) * b) * b) - 1.0);
          	else
          		tmp = Float64(Float64(Float64(a * a) * Float64(a * a)) - 1.0);
          	end
          	return tmp
          end
          
          code[a_, b_] := If[LessEqual[a, 2.5e+21], N[(N[(N[(N[(b * b + 4.0), $MachinePrecision] * b), $MachinePrecision] * b), $MachinePrecision] - 1.0), $MachinePrecision], N[(N[(N[(a * a), $MachinePrecision] * N[(a * a), $MachinePrecision]), $MachinePrecision] - 1.0), $MachinePrecision]]
          
          \begin{array}{l}
          
          \\
          \begin{array}{l}
          \mathbf{if}\;a \leq 2.5 \cdot 10^{+21}:\\
          \;\;\;\;\left(\mathsf{fma}\left(b, b, 4\right) \cdot b\right) \cdot b - 1\\
          
          \mathbf{else}:\\
          \;\;\;\;\left(a \cdot a\right) \cdot \left(a \cdot a\right) - 1\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 2 regimes
          2. if a < 2.5e21

            1. Initial program 99.9%

              \[\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
            2. Add Preprocessing
            3. Taylor expanded in a around 0

              \[\leadsto \color{blue}{\left(2 \cdot \left({a}^{2} \cdot {b}^{2}\right) + \left(4 \cdot {b}^{2} + {b}^{4}\right)\right)} - 1 \]
            4. Step-by-step derivation
              1. associate-+r+N/A

                \[\leadsto \color{blue}{\left(\left(2 \cdot \left({a}^{2} \cdot {b}^{2}\right) + 4 \cdot {b}^{2}\right) + {b}^{4}\right)} - 1 \]
              2. associate-*r*N/A

                \[\leadsto \left(\left(\color{blue}{\left(2 \cdot {a}^{2}\right) \cdot {b}^{2}} + 4 \cdot {b}^{2}\right) + {b}^{4}\right) - 1 \]
              3. distribute-rgt-inN/A

                \[\leadsto \left(\color{blue}{{b}^{2} \cdot \left(2 \cdot {a}^{2} + 4\right)} + {b}^{4}\right) - 1 \]
              4. +-commutativeN/A

                \[\leadsto \left({b}^{2} \cdot \color{blue}{\left(4 + 2 \cdot {a}^{2}\right)} + {b}^{4}\right) - 1 \]
              5. metadata-evalN/A

                \[\leadsto \left({b}^{2} \cdot \left(4 + 2 \cdot {a}^{2}\right) + {b}^{\color{blue}{\left(2 \cdot 2\right)}}\right) - 1 \]
              6. pow-sqrN/A

                \[\leadsto \left({b}^{2} \cdot \left(4 + 2 \cdot {a}^{2}\right) + \color{blue}{{b}^{2} \cdot {b}^{2}}\right) - 1 \]
              7. distribute-lft-inN/A

                \[\leadsto \color{blue}{{b}^{2} \cdot \left(\left(4 + 2 \cdot {a}^{2}\right) + {b}^{2}\right)} - 1 \]
              8. associate-+r+N/A

                \[\leadsto {b}^{2} \cdot \color{blue}{\left(4 + \left(2 \cdot {a}^{2} + {b}^{2}\right)\right)} - 1 \]
              9. *-commutativeN/A

                \[\leadsto \color{blue}{\left(4 + \left(2 \cdot {a}^{2} + {b}^{2}\right)\right) \cdot {b}^{2}} - 1 \]
              10. unpow2N/A

                \[\leadsto \left(4 + \left(2 \cdot {a}^{2} + {b}^{2}\right)\right) \cdot \color{blue}{\left(b \cdot b\right)} - 1 \]
              11. associate-*r*N/A

                \[\leadsto \color{blue}{\left(\left(4 + \left(2 \cdot {a}^{2} + {b}^{2}\right)\right) \cdot b\right) \cdot b} - 1 \]
              12. lower-*.f64N/A

                \[\leadsto \color{blue}{\left(\left(4 + \left(2 \cdot {a}^{2} + {b}^{2}\right)\right) \cdot b\right) \cdot b} - 1 \]
            5. Applied rewrites89.9%

              \[\leadsto \color{blue}{\left(\mathsf{fma}\left(b, b, \mathsf{fma}\left(a \cdot a, 2, 4\right)\right) \cdot b\right) \cdot b} - 1 \]
            6. Taylor expanded in a around 0

              \[\leadsto \left(b \cdot \left(4 + {b}^{2}\right)\right) \cdot b - 1 \]
            7. Step-by-step derivation
              1. Applied rewrites77.2%

                \[\leadsto \left(\mathsf{fma}\left(b, b, 4\right) \cdot b\right) \cdot b - 1 \]

              if 2.5e21 < a

              1. Initial program 99.9%

                \[\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
              2. Add Preprocessing
              3. Taylor expanded in a around inf

                \[\leadsto \color{blue}{{a}^{4}} - 1 \]
              4. Step-by-step derivation
                1. lower-pow.f64100.0

                  \[\leadsto \color{blue}{{a}^{4}} - 1 \]
              5. Applied rewrites100.0%

                \[\leadsto \color{blue}{{a}^{4}} - 1 \]
              6. Step-by-step derivation
                1. Applied rewrites99.9%

                  \[\leadsto \left(a \cdot a\right) \cdot \color{blue}{\left(a \cdot a\right)} - 1 \]
              7. Recombined 2 regimes into one program.
              8. Add Preprocessing

              Alternative 7: 76.8% accurate, 5.2× speedup?

              \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq 4 \cdot 10^{+148}:\\ \;\;\;\;\left(a \cdot a\right) \cdot \left(a \cdot a\right) - 1\\ \mathbf{else}:\\ \;\;\;\;\left(b \cdot b\right) \cdot 4 - 1\\ \end{array} \end{array} \]
              (FPCore (a b)
               :precision binary64
               (if (<= b 4e+148) (- (* (* a a) (* a a)) 1.0) (- (* (* b b) 4.0) 1.0)))
              double code(double a, double b) {
              	double tmp;
              	if (b <= 4e+148) {
              		tmp = ((a * a) * (a * a)) - 1.0;
              	} else {
              		tmp = ((b * b) * 4.0) - 1.0;
              	}
              	return tmp;
              }
              
              real(8) function code(a, b)
                  real(8), intent (in) :: a
                  real(8), intent (in) :: b
                  real(8) :: tmp
                  if (b <= 4d+148) then
                      tmp = ((a * a) * (a * a)) - 1.0d0
                  else
                      tmp = ((b * b) * 4.0d0) - 1.0d0
                  end if
                  code = tmp
              end function
              
              public static double code(double a, double b) {
              	double tmp;
              	if (b <= 4e+148) {
              		tmp = ((a * a) * (a * a)) - 1.0;
              	} else {
              		tmp = ((b * b) * 4.0) - 1.0;
              	}
              	return tmp;
              }
              
              def code(a, b):
              	tmp = 0
              	if b <= 4e+148:
              		tmp = ((a * a) * (a * a)) - 1.0
              	else:
              		tmp = ((b * b) * 4.0) - 1.0
              	return tmp
              
              function code(a, b)
              	tmp = 0.0
              	if (b <= 4e+148)
              		tmp = Float64(Float64(Float64(a * a) * Float64(a * a)) - 1.0);
              	else
              		tmp = Float64(Float64(Float64(b * b) * 4.0) - 1.0);
              	end
              	return tmp
              end
              
              function tmp_2 = code(a, b)
              	tmp = 0.0;
              	if (b <= 4e+148)
              		tmp = ((a * a) * (a * a)) - 1.0;
              	else
              		tmp = ((b * b) * 4.0) - 1.0;
              	end
              	tmp_2 = tmp;
              end
              
              code[a_, b_] := If[LessEqual[b, 4e+148], N[(N[(N[(a * a), $MachinePrecision] * N[(a * a), $MachinePrecision]), $MachinePrecision] - 1.0), $MachinePrecision], N[(N[(N[(b * b), $MachinePrecision] * 4.0), $MachinePrecision] - 1.0), $MachinePrecision]]
              
              \begin{array}{l}
              
              \\
              \begin{array}{l}
              \mathbf{if}\;b \leq 4 \cdot 10^{+148}:\\
              \;\;\;\;\left(a \cdot a\right) \cdot \left(a \cdot a\right) - 1\\
              
              \mathbf{else}:\\
              \;\;\;\;\left(b \cdot b\right) \cdot 4 - 1\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if b < 4.0000000000000002e148

                1. Initial program 99.9%

                  \[\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
                2. Add Preprocessing
                3. Taylor expanded in a around inf

                  \[\leadsto \color{blue}{{a}^{4}} - 1 \]
                4. Step-by-step derivation
                  1. lower-pow.f6472.3

                    \[\leadsto \color{blue}{{a}^{4}} - 1 \]
                5. Applied rewrites72.3%

                  \[\leadsto \color{blue}{{a}^{4}} - 1 \]
                6. Step-by-step derivation
                  1. Applied rewrites72.3%

                    \[\leadsto \left(a \cdot a\right) \cdot \color{blue}{\left(a \cdot a\right)} - 1 \]

                  if 4.0000000000000002e148 < b

                  1. Initial program 100.0%

                    \[\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
                  2. Add Preprocessing
                  3. Taylor expanded in a around 0

                    \[\leadsto \color{blue}{\left(4 \cdot {b}^{2} + {b}^{4}\right)} - 1 \]
                  4. Step-by-step derivation
                    1. *-commutativeN/A

                      \[\leadsto \left(\color{blue}{{b}^{2} \cdot 4} + {b}^{4}\right) - 1 \]
                    2. lower-fma.f64N/A

                      \[\leadsto \color{blue}{\mathsf{fma}\left({b}^{2}, 4, {b}^{4}\right)} - 1 \]
                    3. unpow2N/A

                      \[\leadsto \mathsf{fma}\left(\color{blue}{b \cdot b}, 4, {b}^{4}\right) - 1 \]
                    4. lower-*.f64N/A

                      \[\leadsto \mathsf{fma}\left(\color{blue}{b \cdot b}, 4, {b}^{4}\right) - 1 \]
                    5. lower-pow.f64100.0

                      \[\leadsto \mathsf{fma}\left(b \cdot b, 4, \color{blue}{{b}^{4}}\right) - 1 \]
                  5. Applied rewrites100.0%

                    \[\leadsto \color{blue}{\mathsf{fma}\left(b \cdot b, 4, {b}^{4}\right)} - 1 \]
                  6. Taylor expanded in b around 0

                    \[\leadsto 4 \cdot \color{blue}{{b}^{2}} - 1 \]
                  7. Step-by-step derivation
                    1. Applied rewrites96.7%

                      \[\leadsto \left(b \cdot b\right) \cdot \color{blue}{4} - 1 \]
                  8. Recombined 2 regimes into one program.
                  9. Add Preprocessing

                  Alternative 8: 51.6% accurate, 9.4× speedup?

                  \[\begin{array}{l} \\ \left(b \cdot b\right) \cdot 4 - 1 \end{array} \]
                  (FPCore (a b) :precision binary64 (- (* (* b b) 4.0) 1.0))
                  double code(double a, double b) {
                  	return ((b * b) * 4.0) - 1.0;
                  }
                  
                  real(8) function code(a, b)
                      real(8), intent (in) :: a
                      real(8), intent (in) :: b
                      code = ((b * b) * 4.0d0) - 1.0d0
                  end function
                  
                  public static double code(double a, double b) {
                  	return ((b * b) * 4.0) - 1.0;
                  }
                  
                  def code(a, b):
                  	return ((b * b) * 4.0) - 1.0
                  
                  function code(a, b)
                  	return Float64(Float64(Float64(b * b) * 4.0) - 1.0)
                  end
                  
                  function tmp = code(a, b)
                  	tmp = ((b * b) * 4.0) - 1.0;
                  end
                  
                  code[a_, b_] := N[(N[(N[(b * b), $MachinePrecision] * 4.0), $MachinePrecision] - 1.0), $MachinePrecision]
                  
                  \begin{array}{l}
                  
                  \\
                  \left(b \cdot b\right) \cdot 4 - 1
                  \end{array}
                  
                  Derivation
                  1. Initial program 99.9%

                    \[\left({\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(b \cdot b\right)\right) - 1 \]
                  2. Add Preprocessing
                  3. Taylor expanded in a around 0

                    \[\leadsto \color{blue}{\left(4 \cdot {b}^{2} + {b}^{4}\right)} - 1 \]
                  4. Step-by-step derivation
                    1. *-commutativeN/A

                      \[\leadsto \left(\color{blue}{{b}^{2} \cdot 4} + {b}^{4}\right) - 1 \]
                    2. lower-fma.f64N/A

                      \[\leadsto \color{blue}{\mathsf{fma}\left({b}^{2}, 4, {b}^{4}\right)} - 1 \]
                    3. unpow2N/A

                      \[\leadsto \mathsf{fma}\left(\color{blue}{b \cdot b}, 4, {b}^{4}\right) - 1 \]
                    4. lower-*.f64N/A

                      \[\leadsto \mathsf{fma}\left(\color{blue}{b \cdot b}, 4, {b}^{4}\right) - 1 \]
                    5. lower-pow.f6468.6

                      \[\leadsto \mathsf{fma}\left(b \cdot b, 4, \color{blue}{{b}^{4}}\right) - 1 \]
                  5. Applied rewrites68.6%

                    \[\leadsto \color{blue}{\mathsf{fma}\left(b \cdot b, 4, {b}^{4}\right)} - 1 \]
                  6. Taylor expanded in b around 0

                    \[\leadsto 4 \cdot \color{blue}{{b}^{2}} - 1 \]
                  7. Step-by-step derivation
                    1. Applied rewrites48.1%

                      \[\leadsto \left(b \cdot b\right) \cdot \color{blue}{4} - 1 \]
                    2. Add Preprocessing

                    Reproduce

                    ?
                    herbie shell --seed 2024340 
                    (FPCore (a b)
                      :name "Bouland and Aaronson, Equation (26)"
                      :precision binary64
                      (- (+ (pow (+ (* a a) (* b b)) 2.0) (* 4.0 (* b b))) 1.0))