Bouland and Aaronson, Equation (26)

Percentage Accurate: 99.9% → 99.9%
Time: 7.6s
Alternatives: 11
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 11 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: 69.1% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;{\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(b \cdot b\right) \leq 0.05:\\ \;\;\;\;\mathsf{fma}\left(4 \cdot b, b, -1\right)\\ \mathbf{else}:\\ \;\;\;\;\left(b \cdot b\right) \cdot \left(b \cdot b\right)\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (<= (+ (pow (+ (* a a) (* b b)) 2.0) (* 4.0 (* b b))) 0.05)
   (fma (* 4.0 b) b -1.0)
   (* (* b b) (* b b))))
double code(double a, double b) {
	double tmp;
	if ((pow(((a * a) + (b * b)), 2.0) + (4.0 * (b * b))) <= 0.05) {
		tmp = fma((4.0 * b), b, -1.0);
	} else {
		tmp = (b * b) * (b * b);
	}
	return tmp;
}
function code(a, b)
	tmp = 0.0
	if (Float64((Float64(Float64(a * a) + Float64(b * b)) ^ 2.0) + Float64(4.0 * Float64(b * b))) <= 0.05)
		tmp = fma(Float64(4.0 * b), b, -1.0);
	else
		tmp = Float64(Float64(b * b) * Float64(b * b));
	end
	return tmp
end
code[a_, b_] := If[LessEqual[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], 0.05], N[(N[(4.0 * b), $MachinePrecision] * b + -1.0), $MachinePrecision], N[(N[(b * b), $MachinePrecision] * N[(b * b), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;{\left(a \cdot a + b \cdot b\right)}^{2} + 4 \cdot \left(b \cdot b\right) \leq 0.05:\\
\;\;\;\;\mathsf{fma}\left(4 \cdot b, b, -1\right)\\

\mathbf{else}:\\
\;\;\;\;\left(b \cdot b\right) \cdot \left(b \cdot b\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (+.f64 (pow.f64 (+.f64 (*.f64 a a) (*.f64 b b)) #s(literal 2 binary64)) (*.f64 #s(literal 4 binary64) (*.f64 b b))) < 0.050000000000000003

    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. sub-negN/A

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

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

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

        \[\leadsto \left(\color{blue}{{b}^{2} \cdot {b}^{2}} + 4 \cdot {b}^{2}\right) + \left(\mathsf{neg}\left(1\right)\right) \]
      5. distribute-rgt-outN/A

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

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

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

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

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

        \[\leadsto \mathsf{fma}\left(b \cdot b, \color{blue}{\mathsf{fma}\left(b, b, 4\right)}, \mathsf{neg}\left(1\right)\right) \]
      11. metadata-eval98.3

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

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

      \[\leadsto 4 \cdot {b}^{2} - \color{blue}{1} \]
    7. Step-by-step derivation
      1. Applied rewrites96.8%

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

      if 0.050000000000000003 < (+.f64 (pow.f64 (+.f64 (*.f64 a a) (*.f64 b b)) #s(literal 2 binary64)) (*.f64 #s(literal 4 binary64) (*.f64 b 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 b around 0

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

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

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

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

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

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

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

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

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

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

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

          \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(\color{blue}{a \cdot a}, 2, 4\right) \cdot b, b, {a}^{4}\right) - 1 \]
        12. lower-pow.f6483.0

          \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(a \cdot a, 2, 4\right) \cdot b, b, \color{blue}{{a}^{4}}\right) - 1 \]
      5. Applied rewrites83.0%

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

        \[\leadsto \color{blue}{{b}^{4}} \]
      7. Step-by-step derivation
        1. lower-pow.f6465.9

          \[\leadsto \color{blue}{{b}^{4}} \]
      8. Applied rewrites65.9%

        \[\leadsto \color{blue}{{b}^{4}} \]
      9. Step-by-step derivation
        1. Applied rewrites65.8%

          \[\leadsto \left(b \cdot b\right) \cdot \color{blue}{\left(b \cdot b\right)} \]
      10. Recombined 2 regimes into one program.
      11. Add Preprocessing

      Alternative 3: 98.5% accurate, 0.9× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} t_0 := \mathsf{fma}\left(a \cdot a, 2, 4\right)\\ \mathbf{if}\;b \cdot b \leq 1:\\ \;\;\;\;\mathsf{fma}\left(t\_0 \cdot b, b, {a}^{4}\right) - 1\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\mathsf{fma}\left(b, b, t\_0\right), b \cdot b, -1\right)\\ \end{array} \end{array} \]
      (FPCore (a b)
       :precision binary64
       (let* ((t_0 (fma (* a a) 2.0 4.0)))
         (if (<= (* b b) 1.0)
           (- (fma (* t_0 b) b (pow a 4.0)) 1.0)
           (fma (fma b b t_0) (* b b) -1.0))))
      double code(double a, double b) {
      	double t_0 = fma((a * a), 2.0, 4.0);
      	double tmp;
      	if ((b * b) <= 1.0) {
      		tmp = fma((t_0 * b), b, pow(a, 4.0)) - 1.0;
      	} else {
      		tmp = fma(fma(b, b, t_0), (b * b), -1.0);
      	}
      	return tmp;
      }
      
      function code(a, b)
      	t_0 = fma(Float64(a * a), 2.0, 4.0)
      	tmp = 0.0
      	if (Float64(b * b) <= 1.0)
      		tmp = Float64(fma(Float64(t_0 * b), b, (a ^ 4.0)) - 1.0);
      	else
      		tmp = fma(fma(b, b, t_0), Float64(b * b), -1.0);
      	end
      	return tmp
      end
      
      code[a_, b_] := Block[{t$95$0 = N[(N[(a * a), $MachinePrecision] * 2.0 + 4.0), $MachinePrecision]}, If[LessEqual[N[(b * b), $MachinePrecision], 1.0], N[(N[(N[(t$95$0 * b), $MachinePrecision] * b + N[Power[a, 4.0], $MachinePrecision]), $MachinePrecision] - 1.0), $MachinePrecision], N[(N[(b * b + t$95$0), $MachinePrecision] * N[(b * b), $MachinePrecision] + -1.0), $MachinePrecision]]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      t_0 := \mathsf{fma}\left(a \cdot a, 2, 4\right)\\
      \mathbf{if}\;b \cdot b \leq 1:\\
      \;\;\;\;\mathsf{fma}\left(t\_0 \cdot b, b, {a}^{4}\right) - 1\\
      
      \mathbf{else}:\\
      \;\;\;\;\mathsf{fma}\left(\mathsf{fma}\left(b, b, t\_0\right), b \cdot b, -1\right)\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if (*.f64 b b) < 1

        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

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

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

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

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

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

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

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

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

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

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

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

            \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(\color{blue}{a \cdot a}, 2, 4\right) \cdot b, b, {a}^{4}\right) - 1 \]
          12. lower-pow.f6499.4

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

          \[\leadsto \color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(a \cdot a, 2, 4\right) \cdot b, b, {a}^{4}\right)} - 1 \]

        if 1 < (*.f64 b 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. sub-negN/A

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

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

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

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

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

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

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

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

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

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

            \[\leadsto \color{blue}{\mathsf{fma}\left(4 + \left(2 \cdot {a}^{2} + {b}^{2}\right), {b}^{2}, \mathsf{neg}\left(1\right)\right)} \]
        5. Applied rewrites98.0%

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

      Alternative 4: 98.5% accurate, 2.5× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} t_0 := \mathsf{fma}\left(a \cdot a, 2, 4\right)\\ \mathbf{if}\;b \cdot b \leq 1:\\ \;\;\;\;\mathsf{fma}\left(t\_0 \cdot b, b, \left(a \cdot a\right) \cdot \left(a \cdot a\right)\right) - 1\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\mathsf{fma}\left(b, b, t\_0\right), b \cdot b, -1\right)\\ \end{array} \end{array} \]
      (FPCore (a b)
       :precision binary64
       (let* ((t_0 (fma (* a a) 2.0 4.0)))
         (if (<= (* b b) 1.0)
           (- (fma (* t_0 b) b (* (* a a) (* a a))) 1.0)
           (fma (fma b b t_0) (* b b) -1.0))))
      double code(double a, double b) {
      	double t_0 = fma((a * a), 2.0, 4.0);
      	double tmp;
      	if ((b * b) <= 1.0) {
      		tmp = fma((t_0 * b), b, ((a * a) * (a * a))) - 1.0;
      	} else {
      		tmp = fma(fma(b, b, t_0), (b * b), -1.0);
      	}
      	return tmp;
      }
      
      function code(a, b)
      	t_0 = fma(Float64(a * a), 2.0, 4.0)
      	tmp = 0.0
      	if (Float64(b * b) <= 1.0)
      		tmp = Float64(fma(Float64(t_0 * b), b, Float64(Float64(a * a) * Float64(a * a))) - 1.0);
      	else
      		tmp = fma(fma(b, b, t_0), Float64(b * b), -1.0);
      	end
      	return tmp
      end
      
      code[a_, b_] := Block[{t$95$0 = N[(N[(a * a), $MachinePrecision] * 2.0 + 4.0), $MachinePrecision]}, If[LessEqual[N[(b * b), $MachinePrecision], 1.0], N[(N[(N[(t$95$0 * b), $MachinePrecision] * b + N[(N[(a * a), $MachinePrecision] * N[(a * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - 1.0), $MachinePrecision], N[(N[(b * b + t$95$0), $MachinePrecision] * N[(b * b), $MachinePrecision] + -1.0), $MachinePrecision]]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      t_0 := \mathsf{fma}\left(a \cdot a, 2, 4\right)\\
      \mathbf{if}\;b \cdot b \leq 1:\\
      \;\;\;\;\mathsf{fma}\left(t\_0 \cdot b, b, \left(a \cdot a\right) \cdot \left(a \cdot a\right)\right) - 1\\
      
      \mathbf{else}:\\
      \;\;\;\;\mathsf{fma}\left(\mathsf{fma}\left(b, b, t\_0\right), b \cdot b, -1\right)\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if (*.f64 b b) < 1

        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

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

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

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

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

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

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

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

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

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

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

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

            \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(\color{blue}{a \cdot a}, 2, 4\right) \cdot b, b, {a}^{4}\right) - 1 \]
          12. lower-pow.f6499.4

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

          \[\leadsto \color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(a \cdot a, 2, 4\right) \cdot b, b, {a}^{4}\right)} - 1 \]
        6. Step-by-step derivation
          1. Applied rewrites99.2%

            \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(a \cdot a, 2, 4\right) \cdot b, b, \left(a \cdot a\right) \cdot \left(a \cdot a\right)\right) - 1 \]

          if 1 < (*.f64 b 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. sub-negN/A

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

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

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

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

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

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

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

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

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

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

              \[\leadsto \color{blue}{\mathsf{fma}\left(4 + \left(2 \cdot {a}^{2} + {b}^{2}\right), {b}^{2}, \mathsf{neg}\left(1\right)\right)} \]
          5. Applied rewrites98.0%

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

        Alternative 5: 98.4% accurate, 3.3× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \cdot b \leq 2 \cdot 10^{-10}:\\ \;\;\;\;\left(a \cdot a\right) \cdot \left(a \cdot a\right) - 1\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\mathsf{fma}\left(b, b, \mathsf{fma}\left(a \cdot a, 2, 4\right)\right), b \cdot b, -1\right)\\ \end{array} \end{array} \]
        (FPCore (a b)
         :precision binary64
         (if (<= (* b b) 2e-10)
           (- (* (* a a) (* a a)) 1.0)
           (fma (fma b b (fma (* a a) 2.0 4.0)) (* b b) -1.0)))
        double code(double a, double b) {
        	double tmp;
        	if ((b * b) <= 2e-10) {
        		tmp = ((a * a) * (a * a)) - 1.0;
        	} else {
        		tmp = fma(fma(b, b, fma((a * a), 2.0, 4.0)), (b * b), -1.0);
        	}
        	return tmp;
        }
        
        function code(a, b)
        	tmp = 0.0
        	if (Float64(b * b) <= 2e-10)
        		tmp = Float64(Float64(Float64(a * a) * Float64(a * a)) - 1.0);
        	else
        		tmp = fma(fma(b, b, fma(Float64(a * a), 2.0, 4.0)), Float64(b * b), -1.0);
        	end
        	return tmp
        end
        
        code[a_, b_] := If[LessEqual[N[(b * b), $MachinePrecision], 2e-10], N[(N[(N[(a * a), $MachinePrecision] * N[(a * a), $MachinePrecision]), $MachinePrecision] - 1.0), $MachinePrecision], N[(N[(b * b + N[(N[(a * a), $MachinePrecision] * 2.0 + 4.0), $MachinePrecision]), $MachinePrecision] * N[(b * b), $MachinePrecision] + -1.0), $MachinePrecision]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;b \cdot b \leq 2 \cdot 10^{-10}:\\
        \;\;\;\;\left(a \cdot a\right) \cdot \left(a \cdot a\right) - 1\\
        
        \mathbf{else}:\\
        \;\;\;\;\mathsf{fma}\left(\mathsf{fma}\left(b, b, \mathsf{fma}\left(a \cdot a, 2, 4\right)\right), b \cdot b, -1\right)\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if (*.f64 b b) < 2.00000000000000007e-10

          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%

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

            if 2.00000000000000007e-10 < (*.f64 b 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. sub-negN/A

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

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

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

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

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

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

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

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

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

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

                \[\leadsto \color{blue}{\mathsf{fma}\left(4 + \left(2 \cdot {a}^{2} + {b}^{2}\right), {b}^{2}, \mathsf{neg}\left(1\right)\right)} \]
            5. Applied rewrites97.4%

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

          Alternative 6: 98.5% accurate, 3.4× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \cdot a \leq 12000:\\ \;\;\;\;\mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, b, 4\right), -1\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\mathsf{fma}\left(b \cdot b, 2, a \cdot a\right) \cdot a\right) \cdot a\\ \end{array} \end{array} \]
          (FPCore (a b)
           :precision binary64
           (if (<= (* a a) 12000.0)
             (fma (* b b) (fma b b 4.0) -1.0)
             (* (* (fma (* b b) 2.0 (* a a)) a) a)))
          double code(double a, double b) {
          	double tmp;
          	if ((a * a) <= 12000.0) {
          		tmp = fma((b * b), fma(b, b, 4.0), -1.0);
          	} else {
          		tmp = (fma((b * b), 2.0, (a * a)) * a) * a;
          	}
          	return tmp;
          }
          
          function code(a, b)
          	tmp = 0.0
          	if (Float64(a * a) <= 12000.0)
          		tmp = fma(Float64(b * b), fma(b, b, 4.0), -1.0);
          	else
          		tmp = Float64(Float64(fma(Float64(b * b), 2.0, Float64(a * a)) * a) * a);
          	end
          	return tmp
          end
          
          code[a_, b_] := If[LessEqual[N[(a * a), $MachinePrecision], 12000.0], N[(N[(b * b), $MachinePrecision] * N[(b * b + 4.0), $MachinePrecision] + -1.0), $MachinePrecision], N[(N[(N[(N[(b * b), $MachinePrecision] * 2.0 + N[(a * a), $MachinePrecision]), $MachinePrecision] * a), $MachinePrecision] * a), $MachinePrecision]]
          
          \begin{array}{l}
          
          \\
          \begin{array}{l}
          \mathbf{if}\;a \cdot a \leq 12000:\\
          \;\;\;\;\mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, b, 4\right), -1\right)\\
          
          \mathbf{else}:\\
          \;\;\;\;\left(\mathsf{fma}\left(b \cdot b, 2, a \cdot a\right) \cdot a\right) \cdot a\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 2 regimes
          2. if (*.f64 a a) < 12000

            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. sub-negN/A

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

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

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

                \[\leadsto \left(\color{blue}{{b}^{2} \cdot {b}^{2}} + 4 \cdot {b}^{2}\right) + \left(\mathsf{neg}\left(1\right)\right) \]
              5. distribute-rgt-outN/A

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

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

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

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

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

                \[\leadsto \mathsf{fma}\left(b \cdot b, \color{blue}{\mathsf{fma}\left(b, b, 4\right)}, \mathsf{neg}\left(1\right)\right) \]
              11. metadata-eval99.2

                \[\leadsto \mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, b, 4\right), \color{blue}{-1}\right) \]
            5. Applied rewrites99.2%

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

            if 12000 < (*.f64 a 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

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

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

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

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

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

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

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

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

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

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

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

                \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(\color{blue}{a \cdot a}, 2, 4\right) \cdot b, b, {a}^{4}\right) - 1 \]
              12. lower-pow.f6497.9

                \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(a \cdot a, 2, 4\right) \cdot b, b, \color{blue}{{a}^{4}}\right) - 1 \]
            5. Applied rewrites97.9%

              \[\leadsto \color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(a \cdot a, 2, 4\right) \cdot b, b, {a}^{4}\right)} - 1 \]
            6. Step-by-step derivation
              1. Applied rewrites97.8%

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

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

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

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

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

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

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

                  \[\leadsto {a}^{2} \cdot {a}^{2} + \color{blue}{\frac{2 \cdot {b}^{2}}{{a}^{2}}} \cdot {a}^{4} \]
                7. associate-*l/N/A

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

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

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

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

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

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

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

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

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

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

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

                  \[\leadsto \left(2 \cdot {b}^{2} + {a}^{2}\right) \cdot \color{blue}{\left(a \cdot a\right)} \]
              4. Applied rewrites97.5%

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

            Alternative 7: 94.4% accurate, 4.4× speedup?

            \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \cdot b \leq 2 \cdot 10^{-10}:\\ \;\;\;\;\left(a \cdot a\right) \cdot \left(a \cdot a\right) - 1\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, b, 4\right), -1\right)\\ \end{array} \end{array} \]
            (FPCore (a b)
             :precision binary64
             (if (<= (* b b) 2e-10)
               (- (* (* a a) (* a a)) 1.0)
               (fma (* b b) (fma b b 4.0) -1.0)))
            double code(double a, double b) {
            	double tmp;
            	if ((b * b) <= 2e-10) {
            		tmp = ((a * a) * (a * a)) - 1.0;
            	} else {
            		tmp = fma((b * b), fma(b, b, 4.0), -1.0);
            	}
            	return tmp;
            }
            
            function code(a, b)
            	tmp = 0.0
            	if (Float64(b * b) <= 2e-10)
            		tmp = Float64(Float64(Float64(a * a) * Float64(a * a)) - 1.0);
            	else
            		tmp = fma(Float64(b * b), fma(b, b, 4.0), -1.0);
            	end
            	return tmp
            end
            
            code[a_, b_] := If[LessEqual[N[(b * b), $MachinePrecision], 2e-10], N[(N[(N[(a * a), $MachinePrecision] * N[(a * a), $MachinePrecision]), $MachinePrecision] - 1.0), $MachinePrecision], N[(N[(b * b), $MachinePrecision] * N[(b * b + 4.0), $MachinePrecision] + -1.0), $MachinePrecision]]
            
            \begin{array}{l}
            
            \\
            \begin{array}{l}
            \mathbf{if}\;b \cdot b \leq 2 \cdot 10^{-10}:\\
            \;\;\;\;\left(a \cdot a\right) \cdot \left(a \cdot a\right) - 1\\
            
            \mathbf{else}:\\
            \;\;\;\;\mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, b, 4\right), -1\right)\\
            
            
            \end{array}
            \end{array}
            
            Derivation
            1. Split input into 2 regimes
            2. if (*.f64 b b) < 2.00000000000000007e-10

              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%

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

                if 2.00000000000000007e-10 < (*.f64 b 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

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

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

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

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

                    \[\leadsto \left(\color{blue}{{b}^{2} \cdot {b}^{2}} + 4 \cdot {b}^{2}\right) + \left(\mathsf{neg}\left(1\right)\right) \]
                  5. distribute-rgt-outN/A

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

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

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

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

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

                    \[\leadsto \mathsf{fma}\left(b \cdot b, \color{blue}{\mathsf{fma}\left(b, b, 4\right)}, \mathsf{neg}\left(1\right)\right) \]
                  11. metadata-eval94.7

                    \[\leadsto \mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, b, 4\right), \color{blue}{-1}\right) \]
                5. Applied rewrites94.7%

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

              Alternative 8: 69.1% accurate, 7.3× speedup?

              \[\begin{array}{l} \\ \mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, b, 4\right), -1\right) \end{array} \]
              (FPCore (a b) :precision binary64 (fma (* b b) (fma b b 4.0) -1.0))
              double code(double a, double b) {
              	return fma((b * b), fma(b, b, 4.0), -1.0);
              }
              
              function code(a, b)
              	return fma(Float64(b * b), fma(b, b, 4.0), -1.0)
              end
              
              code[a_, b_] := N[(N[(b * b), $MachinePrecision] * N[(b * b + 4.0), $MachinePrecision] + -1.0), $MachinePrecision]
              
              \begin{array}{l}
              
              \\
              \mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, b, 4\right), -1\right)
              \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. sub-negN/A

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

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

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

                  \[\leadsto \left(\color{blue}{{b}^{2} \cdot {b}^{2}} + 4 \cdot {b}^{2}\right) + \left(\mathsf{neg}\left(1\right)\right) \]
                5. distribute-rgt-outN/A

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

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

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

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

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

                  \[\leadsto \mathsf{fma}\left(b \cdot b, \color{blue}{\mathsf{fma}\left(b, b, 4\right)}, \mathsf{neg}\left(1\right)\right) \]
                11. metadata-eval71.9

                  \[\leadsto \mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, b, 4\right), \color{blue}{-1}\right) \]
              5. Applied rewrites71.9%

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

              Alternative 9: 68.7% accurate, 7.7× speedup?

              \[\begin{array}{l} \\ \mathsf{fma}\left(\left(b \cdot b\right) \cdot b, b, -1\right) \end{array} \]
              (FPCore (a b) :precision binary64 (fma (* (* b b) b) b -1.0))
              double code(double a, double b) {
              	return fma(((b * b) * b), b, -1.0);
              }
              
              function code(a, b)
              	return fma(Float64(Float64(b * b) * b), b, -1.0)
              end
              
              code[a_, b_] := N[(N[(N[(b * b), $MachinePrecision] * b), $MachinePrecision] * b + -1.0), $MachinePrecision]
              
              \begin{array}{l}
              
              \\
              \mathsf{fma}\left(\left(b \cdot b\right) \cdot b, b, -1\right)
              \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. sub-negN/A

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

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

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

                  \[\leadsto \left(\color{blue}{{b}^{2} \cdot {b}^{2}} + 4 \cdot {b}^{2}\right) + \left(\mathsf{neg}\left(1\right)\right) \]
                5. distribute-rgt-outN/A

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

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

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

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

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

                  \[\leadsto \mathsf{fma}\left(b \cdot b, \color{blue}{\mathsf{fma}\left(b, b, 4\right)}, \mathsf{neg}\left(1\right)\right) \]
                11. metadata-eval71.9

                  \[\leadsto \mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, b, 4\right), \color{blue}{-1}\right) \]
              5. Applied rewrites71.9%

                \[\leadsto \color{blue}{\mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, b, 4\right), -1\right)} \]
              6. Step-by-step derivation
                1. Applied rewrites71.9%

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

                  \[\leadsto \mathsf{fma}\left({b}^{2} \cdot b, b, -1\right) \]
                3. Step-by-step derivation
                  1. Applied rewrites71.3%

                    \[\leadsto \mathsf{fma}\left(\left(b \cdot b\right) \cdot b, b, -1\right) \]
                  2. Add Preprocessing

                  Alternative 10: 51.1% accurate, 10.9× speedup?

                  \[\begin{array}{l} \\ \mathsf{fma}\left(4 \cdot b, b, -1\right) \end{array} \]
                  (FPCore (a b) :precision binary64 (fma (* 4.0 b) b -1.0))
                  double code(double a, double b) {
                  	return fma((4.0 * b), b, -1.0);
                  }
                  
                  function code(a, b)
                  	return fma(Float64(4.0 * b), b, -1.0)
                  end
                  
                  code[a_, b_] := N[(N[(4.0 * b), $MachinePrecision] * b + -1.0), $MachinePrecision]
                  
                  \begin{array}{l}
                  
                  \\
                  \mathsf{fma}\left(4 \cdot b, b, -1\right)
                  \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. sub-negN/A

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

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

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

                      \[\leadsto \left(\color{blue}{{b}^{2} \cdot {b}^{2}} + 4 \cdot {b}^{2}\right) + \left(\mathsf{neg}\left(1\right)\right) \]
                    5. distribute-rgt-outN/A

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

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

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

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

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

                      \[\leadsto \mathsf{fma}\left(b \cdot b, \color{blue}{\mathsf{fma}\left(b, b, 4\right)}, \mathsf{neg}\left(1\right)\right) \]
                    11. metadata-eval71.9

                      \[\leadsto \mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, b, 4\right), \color{blue}{-1}\right) \]
                  5. Applied rewrites71.9%

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

                    \[\leadsto 4 \cdot {b}^{2} - \color{blue}{1} \]
                  7. Step-by-step derivation
                    1. Applied rewrites49.2%

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

                    Alternative 11: 24.7% accurate, 131.0× speedup?

                    \[\begin{array}{l} \\ -1 \end{array} \]
                    (FPCore (a b) :precision binary64 -1.0)
                    double code(double a, double b) {
                    	return -1.0;
                    }
                    
                    real(8) function code(a, b)
                        real(8), intent (in) :: a
                        real(8), intent (in) :: b
                        code = -1.0d0
                    end function
                    
                    public static double code(double a, double b) {
                    	return -1.0;
                    }
                    
                    def code(a, b):
                    	return -1.0
                    
                    function code(a, b)
                    	return -1.0
                    end
                    
                    function tmp = code(a, b)
                    	tmp = -1.0;
                    end
                    
                    code[a_, b_] := -1.0
                    
                    \begin{array}{l}
                    
                    \\
                    -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. sub-negN/A

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

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

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

                        \[\leadsto \left(\color{blue}{{b}^{2} \cdot {b}^{2}} + 4 \cdot {b}^{2}\right) + \left(\mathsf{neg}\left(1\right)\right) \]
                      5. distribute-rgt-outN/A

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

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

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

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

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

                        \[\leadsto \mathsf{fma}\left(b \cdot b, \color{blue}{\mathsf{fma}\left(b, b, 4\right)}, \mathsf{neg}\left(1\right)\right) \]
                      11. metadata-eval71.9

                        \[\leadsto \mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, b, 4\right), \color{blue}{-1}\right) \]
                    5. Applied rewrites71.9%

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

                      \[\leadsto -1 \]
                    7. Step-by-step derivation
                      1. Applied rewrites19.3%

                        \[\leadsto -1 \]
                      2. Add Preprocessing

                      Reproduce

                      ?
                      herbie shell --seed 2024307 
                      (FPCore (a b)
                        :name "Bouland and Aaronson, Equation (26)"
                        :precision binary64
                        (- (+ (pow (+ (* a a) (* b b)) 2.0) (* 4.0 (* b b))) 1.0))