ENA, Section 1.4, Exercise 4a

Percentage Accurate: 52.7% → 99.6%
Time: 15.1s
Alternatives: 8
Speedup: 19.5×

Specification

?
\[-1 \leq x \land x \leq 1\]
\[\begin{array}{l} \\ \frac{x - \sin x}{\tan x} \end{array} \]
(FPCore (x) :precision binary64 (/ (- x (sin x)) (tan x)))
double code(double x) {
	return (x - sin(x)) / tan(x);
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (x - sin(x)) / tan(x)
end function
public static double code(double x) {
	return (x - Math.sin(x)) / Math.tan(x);
}
def code(x):
	return (x - math.sin(x)) / math.tan(x)
function code(x)
	return Float64(Float64(x - sin(x)) / tan(x))
end
function tmp = code(x)
	tmp = (x - sin(x)) / tan(x);
end
code[x_] := N[(N[(x - N[Sin[x], $MachinePrecision]), $MachinePrecision] / N[Tan[x], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{x - \sin x}{\tan x}
\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: 52.7% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{x - \sin x}{\tan x} \end{array} \]
(FPCore (x) :precision binary64 (/ (- x (sin x)) (tan x)))
double code(double x) {
	return (x - sin(x)) / tan(x);
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (x - sin(x)) / tan(x)
end function
public static double code(double x) {
	return (x - Math.sin(x)) / Math.tan(x);
}
def code(x):
	return (x - math.sin(x)) / math.tan(x)
function code(x)
	return Float64(Float64(x - sin(x)) / tan(x))
end
function tmp = code(x)
	tmp = (x - sin(x)) / tan(x);
end
code[x_] := N[(N[(x - N[Sin[x], $MachinePrecision]), $MachinePrecision] / N[Tan[x], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{x - \sin x}{\tan x}
\end{array}

Alternative 1: 99.6% accurate, 4.3× speedup?

\[\begin{array}{l} \\ \frac{x \cdot x}{\frac{1}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right)}} \end{array} \]
(FPCore (x)
 :precision binary64
 (/
  (* x x)
  (/
   1.0
   (fma
    (* x x)
    (fma x (* x -0.0007275132275132275) -0.06388888888888888)
    0.16666666666666666))))
double code(double x) {
	return (x * x) / (1.0 / fma((x * x), fma(x, (x * -0.0007275132275132275), -0.06388888888888888), 0.16666666666666666));
}
function code(x)
	return Float64(Float64(x * x) / Float64(1.0 / fma(Float64(x * x), fma(x, Float64(x * -0.0007275132275132275), -0.06388888888888888), 0.16666666666666666)))
end
code[x_] := N[(N[(x * x), $MachinePrecision] / N[(1.0 / N[(N[(x * x), $MachinePrecision] * N[(x * N[(x * -0.0007275132275132275), $MachinePrecision] + -0.06388888888888888), $MachinePrecision] + 0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{x \cdot x}{\frac{1}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right)}}
\end{array}
Derivation
  1. Initial program 49.3%

    \[\frac{x - \sin x}{\tan x} \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0

    \[\leadsto \color{blue}{{x}^{2} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right)} \]
  4. Step-by-step derivation
    1. unpow2N/A

      \[\leadsto \color{blue}{\left(x \cdot x\right)} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right) \]
    2. associate-*l*N/A

      \[\leadsto \color{blue}{x \cdot \left(x \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right)\right)} \]
    3. lower-*.f64N/A

      \[\leadsto \color{blue}{x \cdot \left(x \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right)\right)} \]
    4. lower-*.f64N/A

      \[\leadsto x \cdot \color{blue}{\left(x \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right)\right)} \]
    5. +-commutativeN/A

      \[\leadsto x \cdot \left(x \cdot \color{blue}{\left({x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right) + \frac{1}{6}\right)}\right) \]
    6. lower-fma.f64N/A

      \[\leadsto x \cdot \left(x \cdot \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}, \frac{1}{6}\right)}\right) \]
    7. unpow2N/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}, \frac{1}{6}\right)\right) \]
    8. lower-*.f64N/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}, \frac{1}{6}\right)\right) \]
    9. sub-negN/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{\frac{-11}{15120} \cdot {x}^{2} + \left(\mathsf{neg}\left(\frac{23}{360}\right)\right)}, \frac{1}{6}\right)\right) \]
    10. *-commutativeN/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{{x}^{2} \cdot \frac{-11}{15120}} + \left(\mathsf{neg}\left(\frac{23}{360}\right)\right), \frac{1}{6}\right)\right) \]
    11. metadata-evalN/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, {x}^{2} \cdot \frac{-11}{15120} + \color{blue}{\frac{-23}{360}}, \frac{1}{6}\right)\right) \]
    12. lower-fma.f64N/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{-11}{15120}, \frac{-23}{360}\right)}, \frac{1}{6}\right)\right) \]
    13. unpow2N/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-11}{15120}, \frac{-23}{360}\right), \frac{1}{6}\right)\right) \]
    14. lower-*.f6499.6

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right)\right) \]
  5. Simplified99.6%

    \[\leadsto \color{blue}{x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right)\right)} \]
  6. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto x \cdot \left(x \cdot \left(\color{blue}{\left(x \cdot x\right)} \cdot \left(\left(x \cdot x\right) \cdot \frac{-11}{15120} + \frac{-23}{360}\right) + \frac{1}{6}\right)\right) \]
    2. lift-*.f64N/A

      \[\leadsto x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \left(\color{blue}{\left(x \cdot x\right)} \cdot \frac{-11}{15120} + \frac{-23}{360}\right) + \frac{1}{6}\right)\right) \]
    3. lift-fma.f64N/A

      \[\leadsto x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \color{blue}{\mathsf{fma}\left(x \cdot x, \frac{-11}{15120}, \frac{-23}{360}\right)} + \frac{1}{6}\right)\right) \]
    4. lift-fma.f64N/A

      \[\leadsto x \cdot \left(x \cdot \color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{-11}{15120}, \frac{-23}{360}\right), \frac{1}{6}\right)}\right) \]
    5. associate-*r*N/A

      \[\leadsto \color{blue}{\left(x \cdot x\right) \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{-11}{15120}, \frac{-23}{360}\right), \frac{1}{6}\right)} \]
    6. lift-*.f64N/A

      \[\leadsto \color{blue}{\left(x \cdot x\right)} \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{-11}{15120}, \frac{-23}{360}\right), \frac{1}{6}\right) \]
    7. *-commutativeN/A

      \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{-11}{15120}, \frac{-23}{360}\right), \frac{1}{6}\right) \cdot \left(x \cdot x\right)} \]
    8. lower-*.f6499.6

      \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right) \cdot \left(x \cdot x\right)} \]
    9. lift-fma.f64N/A

      \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{\left(x \cdot x\right) \cdot \frac{-11}{15120} + \frac{-23}{360}}, \frac{1}{6}\right) \cdot \left(x \cdot x\right) \]
    10. lift-*.f64N/A

      \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{\left(x \cdot x\right)} \cdot \frac{-11}{15120} + \frac{-23}{360}, \frac{1}{6}\right) \cdot \left(x \cdot x\right) \]
    11. associate-*l*N/A

      \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{x \cdot \left(x \cdot \frac{-11}{15120}\right)} + \frac{-23}{360}, \frac{1}{6}\right) \cdot \left(x \cdot x\right) \]
    12. lower-fma.f64N/A

      \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left(x, x \cdot \frac{-11}{15120}, \frac{-23}{360}\right)}, \frac{1}{6}\right) \cdot \left(x \cdot x\right) \]
    13. lower-*.f6499.6

      \[\leadsto \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, \color{blue}{x \cdot -0.0007275132275132275}, -0.06388888888888888\right), 0.16666666666666666\right) \cdot \left(x \cdot x\right) \]
  7. Applied egg-rr99.6%

    \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right) \cdot \left(x \cdot x\right)} \]
  8. Applied egg-rr99.6%

    \[\leadsto \color{blue}{\frac{x \cdot x}{\frac{1}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right)}}} \]
  9. Add Preprocessing

Alternative 2: 99.6% accurate, 4.9× speedup?

\[\begin{array}{l} \\ x \cdot \left(x \cdot \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x \cdot x, -0.00023644179894179894, -0.0007275132275132275\right), -0.06388888888888888\right), 0.16666666666666666\right)\right) \end{array} \]
(FPCore (x)
 :precision binary64
 (*
  x
  (*
   x
   (fma
    x
    (*
     x
     (fma
      x
      (* x (fma (* x x) -0.00023644179894179894 -0.0007275132275132275))
      -0.06388888888888888))
    0.16666666666666666))))
double code(double x) {
	return x * (x * fma(x, (x * fma(x, (x * fma((x * x), -0.00023644179894179894, -0.0007275132275132275)), -0.06388888888888888)), 0.16666666666666666));
}
function code(x)
	return Float64(x * Float64(x * fma(x, Float64(x * fma(x, Float64(x * fma(Float64(x * x), -0.00023644179894179894, -0.0007275132275132275)), -0.06388888888888888)), 0.16666666666666666)))
end
code[x_] := N[(x * N[(x * N[(x * N[(x * N[(x * N[(x * N[(N[(x * x), $MachinePrecision] * -0.00023644179894179894 + -0.0007275132275132275), $MachinePrecision]), $MachinePrecision] + -0.06388888888888888), $MachinePrecision]), $MachinePrecision] + 0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
x \cdot \left(x \cdot \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x \cdot x, -0.00023644179894179894, -0.0007275132275132275\right), -0.06388888888888888\right), 0.16666666666666666\right)\right)
\end{array}
Derivation
  1. Initial program 49.3%

    \[\frac{x - \sin x}{\tan x} \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0

    \[\leadsto \color{blue}{{x}^{2} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right)} \]
  4. Step-by-step derivation
    1. unpow2N/A

      \[\leadsto \color{blue}{\left(x \cdot x\right)} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \]
    2. associate-*l*N/A

      \[\leadsto \color{blue}{x \cdot \left(x \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right)\right)} \]
    3. *-commutativeN/A

      \[\leadsto x \cdot \color{blue}{\left(\left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot x\right)} \]
    4. lower-*.f64N/A

      \[\leadsto \color{blue}{x \cdot \left(\left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot x\right)} \]
    5. *-commutativeN/A

      \[\leadsto x \cdot \color{blue}{\left(x \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right)\right)} \]
    6. lower-*.f64N/A

      \[\leadsto x \cdot \color{blue}{\left(x \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right)\right)} \]
    7. +-commutativeN/A

      \[\leadsto x \cdot \left(x \cdot \color{blue}{\left({x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right) + \frac{1}{6}\right)}\right) \]
    8. unpow2N/A

      \[\leadsto x \cdot \left(x \cdot \left(\color{blue}{\left(x \cdot x\right)} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right) + \frac{1}{6}\right)\right) \]
    9. associate-*l*N/A

      \[\leadsto x \cdot \left(x \cdot \left(\color{blue}{x \cdot \left(x \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right)} + \frac{1}{6}\right)\right) \]
    10. lower-fma.f64N/A

      \[\leadsto x \cdot \left(x \cdot \color{blue}{\mathsf{fma}\left(x, x \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right), \frac{1}{6}\right)}\right) \]
  5. Simplified99.6%

    \[\leadsto \color{blue}{x \cdot \left(x \cdot \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x \cdot x, -0.00023644179894179894, -0.0007275132275132275\right), -0.06388888888888888\right), 0.16666666666666666\right)\right)} \]
  6. Add Preprocessing

Alternative 3: 99.5% accurate, 6.5× speedup?

\[\begin{array}{l} \\ \left(x \cdot x\right) \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right) \end{array} \]
(FPCore (x)
 :precision binary64
 (*
  (* x x)
  (fma
   (* x x)
   (fma x (* x -0.0007275132275132275) -0.06388888888888888)
   0.16666666666666666)))
double code(double x) {
	return (x * x) * fma((x * x), fma(x, (x * -0.0007275132275132275), -0.06388888888888888), 0.16666666666666666);
}
function code(x)
	return Float64(Float64(x * x) * fma(Float64(x * x), fma(x, Float64(x * -0.0007275132275132275), -0.06388888888888888), 0.16666666666666666))
end
code[x_] := N[(N[(x * x), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * N[(x * N[(x * -0.0007275132275132275), $MachinePrecision] + -0.06388888888888888), $MachinePrecision] + 0.16666666666666666), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(x \cdot x\right) \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right)
\end{array}
Derivation
  1. Initial program 49.3%

    \[\frac{x - \sin x}{\tan x} \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0

    \[\leadsto \color{blue}{{x}^{2} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right)} \]
  4. Step-by-step derivation
    1. unpow2N/A

      \[\leadsto \color{blue}{\left(x \cdot x\right)} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right) \]
    2. associate-*l*N/A

      \[\leadsto \color{blue}{x \cdot \left(x \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right)\right)} \]
    3. lower-*.f64N/A

      \[\leadsto \color{blue}{x \cdot \left(x \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right)\right)} \]
    4. lower-*.f64N/A

      \[\leadsto x \cdot \color{blue}{\left(x \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right)\right)} \]
    5. +-commutativeN/A

      \[\leadsto x \cdot \left(x \cdot \color{blue}{\left({x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right) + \frac{1}{6}\right)}\right) \]
    6. lower-fma.f64N/A

      \[\leadsto x \cdot \left(x \cdot \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}, \frac{1}{6}\right)}\right) \]
    7. unpow2N/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}, \frac{1}{6}\right)\right) \]
    8. lower-*.f64N/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}, \frac{1}{6}\right)\right) \]
    9. sub-negN/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{\frac{-11}{15120} \cdot {x}^{2} + \left(\mathsf{neg}\left(\frac{23}{360}\right)\right)}, \frac{1}{6}\right)\right) \]
    10. *-commutativeN/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{{x}^{2} \cdot \frac{-11}{15120}} + \left(\mathsf{neg}\left(\frac{23}{360}\right)\right), \frac{1}{6}\right)\right) \]
    11. metadata-evalN/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, {x}^{2} \cdot \frac{-11}{15120} + \color{blue}{\frac{-23}{360}}, \frac{1}{6}\right)\right) \]
    12. lower-fma.f64N/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{-11}{15120}, \frac{-23}{360}\right)}, \frac{1}{6}\right)\right) \]
    13. unpow2N/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-11}{15120}, \frac{-23}{360}\right), \frac{1}{6}\right)\right) \]
    14. lower-*.f6499.6

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right)\right) \]
  5. Simplified99.6%

    \[\leadsto \color{blue}{x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right)\right)} \]
  6. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto x \cdot \left(x \cdot \left(\color{blue}{\left(x \cdot x\right)} \cdot \left(\left(x \cdot x\right) \cdot \frac{-11}{15120} + \frac{-23}{360}\right) + \frac{1}{6}\right)\right) \]
    2. lift-*.f64N/A

      \[\leadsto x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \left(\color{blue}{\left(x \cdot x\right)} \cdot \frac{-11}{15120} + \frac{-23}{360}\right) + \frac{1}{6}\right)\right) \]
    3. lift-fma.f64N/A

      \[\leadsto x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \color{blue}{\mathsf{fma}\left(x \cdot x, \frac{-11}{15120}, \frac{-23}{360}\right)} + \frac{1}{6}\right)\right) \]
    4. lift-fma.f64N/A

      \[\leadsto x \cdot \left(x \cdot \color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{-11}{15120}, \frac{-23}{360}\right), \frac{1}{6}\right)}\right) \]
    5. associate-*r*N/A

      \[\leadsto \color{blue}{\left(x \cdot x\right) \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{-11}{15120}, \frac{-23}{360}\right), \frac{1}{6}\right)} \]
    6. lift-*.f64N/A

      \[\leadsto \color{blue}{\left(x \cdot x\right)} \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{-11}{15120}, \frac{-23}{360}\right), \frac{1}{6}\right) \]
    7. *-commutativeN/A

      \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{-11}{15120}, \frac{-23}{360}\right), \frac{1}{6}\right) \cdot \left(x \cdot x\right)} \]
    8. lower-*.f6499.6

      \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right) \cdot \left(x \cdot x\right)} \]
    9. lift-fma.f64N/A

      \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{\left(x \cdot x\right) \cdot \frac{-11}{15120} + \frac{-23}{360}}, \frac{1}{6}\right) \cdot \left(x \cdot x\right) \]
    10. lift-*.f64N/A

      \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{\left(x \cdot x\right)} \cdot \frac{-11}{15120} + \frac{-23}{360}, \frac{1}{6}\right) \cdot \left(x \cdot x\right) \]
    11. associate-*l*N/A

      \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{x \cdot \left(x \cdot \frac{-11}{15120}\right)} + \frac{-23}{360}, \frac{1}{6}\right) \cdot \left(x \cdot x\right) \]
    12. lower-fma.f64N/A

      \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left(x, x \cdot \frac{-11}{15120}, \frac{-23}{360}\right)}, \frac{1}{6}\right) \cdot \left(x \cdot x\right) \]
    13. lower-*.f6499.6

      \[\leadsto \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, \color{blue}{x \cdot -0.0007275132275132275}, -0.06388888888888888\right), 0.16666666666666666\right) \cdot \left(x \cdot x\right) \]
  7. Applied egg-rr99.6%

    \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right) \cdot \left(x \cdot x\right)} \]
  8. Final simplification99.6%

    \[\leadsto \left(x \cdot x\right) \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right) \]
  9. Add Preprocessing

Alternative 4: 99.5% accurate, 6.5× speedup?

\[\begin{array}{l} \\ x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right)\right) \end{array} \]
(FPCore (x)
 :precision binary64
 (*
  x
  (*
   x
   (fma
    (* x x)
    (fma (* x x) -0.0007275132275132275 -0.06388888888888888)
    0.16666666666666666))))
double code(double x) {
	return x * (x * fma((x * x), fma((x * x), -0.0007275132275132275, -0.06388888888888888), 0.16666666666666666));
}
function code(x)
	return Float64(x * Float64(x * fma(Float64(x * x), fma(Float64(x * x), -0.0007275132275132275, -0.06388888888888888), 0.16666666666666666)))
end
code[x_] := N[(x * N[(x * N[(N[(x * x), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * -0.0007275132275132275 + -0.06388888888888888), $MachinePrecision] + 0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right)\right)
\end{array}
Derivation
  1. Initial program 49.3%

    \[\frac{x - \sin x}{\tan x} \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0

    \[\leadsto \color{blue}{{x}^{2} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right)} \]
  4. Step-by-step derivation
    1. unpow2N/A

      \[\leadsto \color{blue}{\left(x \cdot x\right)} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right) \]
    2. associate-*l*N/A

      \[\leadsto \color{blue}{x \cdot \left(x \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right)\right)} \]
    3. lower-*.f64N/A

      \[\leadsto \color{blue}{x \cdot \left(x \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right)\right)} \]
    4. lower-*.f64N/A

      \[\leadsto x \cdot \color{blue}{\left(x \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right)\right)} \]
    5. +-commutativeN/A

      \[\leadsto x \cdot \left(x \cdot \color{blue}{\left({x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right) + \frac{1}{6}\right)}\right) \]
    6. lower-fma.f64N/A

      \[\leadsto x \cdot \left(x \cdot \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}, \frac{1}{6}\right)}\right) \]
    7. unpow2N/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}, \frac{1}{6}\right)\right) \]
    8. lower-*.f64N/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}, \frac{1}{6}\right)\right) \]
    9. sub-negN/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{\frac{-11}{15120} \cdot {x}^{2} + \left(\mathsf{neg}\left(\frac{23}{360}\right)\right)}, \frac{1}{6}\right)\right) \]
    10. *-commutativeN/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{{x}^{2} \cdot \frac{-11}{15120}} + \left(\mathsf{neg}\left(\frac{23}{360}\right)\right), \frac{1}{6}\right)\right) \]
    11. metadata-evalN/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, {x}^{2} \cdot \frac{-11}{15120} + \color{blue}{\frac{-23}{360}}, \frac{1}{6}\right)\right) \]
    12. lower-fma.f64N/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{-11}{15120}, \frac{-23}{360}\right)}, \frac{1}{6}\right)\right) \]
    13. unpow2N/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-11}{15120}, \frac{-23}{360}\right), \frac{1}{6}\right)\right) \]
    14. lower-*.f6499.6

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right)\right) \]
  5. Simplified99.6%

    \[\leadsto \color{blue}{x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right)\right)} \]
  6. Add Preprocessing

Alternative 5: 99.4% accurate, 9.8× speedup?

\[\begin{array}{l} \\ \left(x \cdot x\right) \cdot \mathsf{fma}\left(x \cdot x, -0.06388888888888888, 0.16666666666666666\right) \end{array} \]
(FPCore (x)
 :precision binary64
 (* (* x x) (fma (* x x) -0.06388888888888888 0.16666666666666666)))
double code(double x) {
	return (x * x) * fma((x * x), -0.06388888888888888, 0.16666666666666666);
}
function code(x)
	return Float64(Float64(x * x) * fma(Float64(x * x), -0.06388888888888888, 0.16666666666666666))
end
code[x_] := N[(N[(x * x), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * -0.06388888888888888 + 0.16666666666666666), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(x \cdot x\right) \cdot \mathsf{fma}\left(x \cdot x, -0.06388888888888888, 0.16666666666666666\right)
\end{array}
Derivation
  1. Initial program 49.3%

    \[\frac{x - \sin x}{\tan x} \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0

    \[\leadsto \color{blue}{{x}^{2} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right)} \]
  4. Step-by-step derivation
    1. unpow2N/A

      \[\leadsto \color{blue}{\left(x \cdot x\right)} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right) \]
    2. associate-*l*N/A

      \[\leadsto \color{blue}{x \cdot \left(x \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right)\right)} \]
    3. lower-*.f64N/A

      \[\leadsto \color{blue}{x \cdot \left(x \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right)\right)} \]
    4. lower-*.f64N/A

      \[\leadsto x \cdot \color{blue}{\left(x \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right)\right)} \]
    5. +-commutativeN/A

      \[\leadsto x \cdot \left(x \cdot \color{blue}{\left({x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right) + \frac{1}{6}\right)}\right) \]
    6. lower-fma.f64N/A

      \[\leadsto x \cdot \left(x \cdot \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}, \frac{1}{6}\right)}\right) \]
    7. unpow2N/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}, \frac{1}{6}\right)\right) \]
    8. lower-*.f64N/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}, \frac{1}{6}\right)\right) \]
    9. sub-negN/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{\frac{-11}{15120} \cdot {x}^{2} + \left(\mathsf{neg}\left(\frac{23}{360}\right)\right)}, \frac{1}{6}\right)\right) \]
    10. *-commutativeN/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{{x}^{2} \cdot \frac{-11}{15120}} + \left(\mathsf{neg}\left(\frac{23}{360}\right)\right), \frac{1}{6}\right)\right) \]
    11. metadata-evalN/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, {x}^{2} \cdot \frac{-11}{15120} + \color{blue}{\frac{-23}{360}}, \frac{1}{6}\right)\right) \]
    12. lower-fma.f64N/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{-11}{15120}, \frac{-23}{360}\right)}, \frac{1}{6}\right)\right) \]
    13. unpow2N/A

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-11}{15120}, \frac{-23}{360}\right), \frac{1}{6}\right)\right) \]
    14. lower-*.f6499.6

      \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right)\right) \]
  5. Simplified99.6%

    \[\leadsto \color{blue}{x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right)\right)} \]
  6. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto x \cdot \left(x \cdot \left(\color{blue}{\left(x \cdot x\right)} \cdot \left(\left(x \cdot x\right) \cdot \frac{-11}{15120} + \frac{-23}{360}\right) + \frac{1}{6}\right)\right) \]
    2. lift-*.f64N/A

      \[\leadsto x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \left(\color{blue}{\left(x \cdot x\right)} \cdot \frac{-11}{15120} + \frac{-23}{360}\right) + \frac{1}{6}\right)\right) \]
    3. lift-fma.f64N/A

      \[\leadsto x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \color{blue}{\mathsf{fma}\left(x \cdot x, \frac{-11}{15120}, \frac{-23}{360}\right)} + \frac{1}{6}\right)\right) \]
    4. lift-fma.f64N/A

      \[\leadsto x \cdot \left(x \cdot \color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{-11}{15120}, \frac{-23}{360}\right), \frac{1}{6}\right)}\right) \]
    5. associate-*r*N/A

      \[\leadsto \color{blue}{\left(x \cdot x\right) \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{-11}{15120}, \frac{-23}{360}\right), \frac{1}{6}\right)} \]
    6. lift-*.f64N/A

      \[\leadsto \color{blue}{\left(x \cdot x\right)} \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{-11}{15120}, \frac{-23}{360}\right), \frac{1}{6}\right) \]
    7. *-commutativeN/A

      \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{-11}{15120}, \frac{-23}{360}\right), \frac{1}{6}\right) \cdot \left(x \cdot x\right)} \]
    8. lower-*.f6499.6

      \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right) \cdot \left(x \cdot x\right)} \]
    9. lift-fma.f64N/A

      \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{\left(x \cdot x\right) \cdot \frac{-11}{15120} + \frac{-23}{360}}, \frac{1}{6}\right) \cdot \left(x \cdot x\right) \]
    10. lift-*.f64N/A

      \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{\left(x \cdot x\right)} \cdot \frac{-11}{15120} + \frac{-23}{360}, \frac{1}{6}\right) \cdot \left(x \cdot x\right) \]
    11. associate-*l*N/A

      \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{x \cdot \left(x \cdot \frac{-11}{15120}\right)} + \frac{-23}{360}, \frac{1}{6}\right) \cdot \left(x \cdot x\right) \]
    12. lower-fma.f64N/A

      \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left(x, x \cdot \frac{-11}{15120}, \frac{-23}{360}\right)}, \frac{1}{6}\right) \cdot \left(x \cdot x\right) \]
    13. lower-*.f6499.6

      \[\leadsto \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, \color{blue}{x \cdot -0.0007275132275132275}, -0.06388888888888888\right), 0.16666666666666666\right) \cdot \left(x \cdot x\right) \]
  7. Applied egg-rr99.6%

    \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right) \cdot \left(x \cdot x\right)} \]
  8. Taylor expanded in x around 0

    \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{\frac{-23}{360}}, \frac{1}{6}\right) \cdot \left(x \cdot x\right) \]
  9. Step-by-step derivation
    1. Simplified99.4%

      \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{-0.06388888888888888}, 0.16666666666666666\right) \cdot \left(x \cdot x\right) \]
    2. Final simplification99.4%

      \[\leadsto \left(x \cdot x\right) \cdot \mathsf{fma}\left(x \cdot x, -0.06388888888888888, 0.16666666666666666\right) \]
    3. Add Preprocessing

    Alternative 6: 99.4% accurate, 9.8× speedup?

    \[\begin{array}{l} \\ x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, -0.06388888888888888, 0.16666666666666666\right)\right) \end{array} \]
    (FPCore (x)
     :precision binary64
     (* x (* x (fma (* x x) -0.06388888888888888 0.16666666666666666))))
    double code(double x) {
    	return x * (x * fma((x * x), -0.06388888888888888, 0.16666666666666666));
    }
    
    function code(x)
    	return Float64(x * Float64(x * fma(Float64(x * x), -0.06388888888888888, 0.16666666666666666)))
    end
    
    code[x_] := N[(x * N[(x * N[(N[(x * x), $MachinePrecision] * -0.06388888888888888 + 0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, -0.06388888888888888, 0.16666666666666666\right)\right)
    \end{array}
    
    Derivation
    1. Initial program 49.3%

      \[\frac{x - \sin x}{\tan x} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \color{blue}{{x}^{2} \cdot \left(\frac{1}{6} + \frac{-23}{360} \cdot {x}^{2}\right)} \]
    4. Step-by-step derivation
      1. unpow2N/A

        \[\leadsto \color{blue}{\left(x \cdot x\right)} \cdot \left(\frac{1}{6} + \frac{-23}{360} \cdot {x}^{2}\right) \]
      2. associate-*l*N/A

        \[\leadsto \color{blue}{x \cdot \left(x \cdot \left(\frac{1}{6} + \frac{-23}{360} \cdot {x}^{2}\right)\right)} \]
      3. lower-*.f64N/A

        \[\leadsto \color{blue}{x \cdot \left(x \cdot \left(\frac{1}{6} + \frac{-23}{360} \cdot {x}^{2}\right)\right)} \]
      4. lower-*.f64N/A

        \[\leadsto x \cdot \color{blue}{\left(x \cdot \left(\frac{1}{6} + \frac{-23}{360} \cdot {x}^{2}\right)\right)} \]
      5. +-commutativeN/A

        \[\leadsto x \cdot \left(x \cdot \color{blue}{\left(\frac{-23}{360} \cdot {x}^{2} + \frac{1}{6}\right)}\right) \]
      6. *-commutativeN/A

        \[\leadsto x \cdot \left(x \cdot \left(\color{blue}{{x}^{2} \cdot \frac{-23}{360}} + \frac{1}{6}\right)\right) \]
      7. lower-fma.f64N/A

        \[\leadsto x \cdot \left(x \cdot \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{-23}{360}, \frac{1}{6}\right)}\right) \]
      8. unpow2N/A

        \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-23}{360}, \frac{1}{6}\right)\right) \]
      9. lower-*.f6499.4

        \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, -0.06388888888888888, 0.16666666666666666\right)\right) \]
    5. Simplified99.4%

      \[\leadsto \color{blue}{x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, -0.06388888888888888, 0.16666666666666666\right)\right)} \]
    6. Add Preprocessing

    Alternative 7: 99.0% accurate, 12.6× speedup?

    \[\begin{array}{l} \\ \frac{x \cdot x}{6} \end{array} \]
    (FPCore (x) :precision binary64 (/ (* x x) 6.0))
    double code(double x) {
    	return (x * x) / 6.0;
    }
    
    real(8) function code(x)
        real(8), intent (in) :: x
        code = (x * x) / 6.0d0
    end function
    
    public static double code(double x) {
    	return (x * x) / 6.0;
    }
    
    def code(x):
    	return (x * x) / 6.0
    
    function code(x)
    	return Float64(Float64(x * x) / 6.0)
    end
    
    function tmp = code(x)
    	tmp = (x * x) / 6.0;
    end
    
    code[x_] := N[(N[(x * x), $MachinePrecision] / 6.0), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \frac{x \cdot x}{6}
    \end{array}
    
    Derivation
    1. Initial program 49.3%

      \[\frac{x - \sin x}{\tan x} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \color{blue}{{x}^{2} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right)} \]
    4. Step-by-step derivation
      1. unpow2N/A

        \[\leadsto \color{blue}{\left(x \cdot x\right)} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right) \]
      2. associate-*l*N/A

        \[\leadsto \color{blue}{x \cdot \left(x \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right)\right)} \]
      3. lower-*.f64N/A

        \[\leadsto \color{blue}{x \cdot \left(x \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right)\right)} \]
      4. lower-*.f64N/A

        \[\leadsto x \cdot \color{blue}{\left(x \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right)\right)} \]
      5. +-commutativeN/A

        \[\leadsto x \cdot \left(x \cdot \color{blue}{\left({x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right) + \frac{1}{6}\right)}\right) \]
      6. lower-fma.f64N/A

        \[\leadsto x \cdot \left(x \cdot \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}, \frac{1}{6}\right)}\right) \]
      7. unpow2N/A

        \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}, \frac{1}{6}\right)\right) \]
      8. lower-*.f64N/A

        \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}, \frac{1}{6}\right)\right) \]
      9. sub-negN/A

        \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{\frac{-11}{15120} \cdot {x}^{2} + \left(\mathsf{neg}\left(\frac{23}{360}\right)\right)}, \frac{1}{6}\right)\right) \]
      10. *-commutativeN/A

        \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{{x}^{2} \cdot \frac{-11}{15120}} + \left(\mathsf{neg}\left(\frac{23}{360}\right)\right), \frac{1}{6}\right)\right) \]
      11. metadata-evalN/A

        \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, {x}^{2} \cdot \frac{-11}{15120} + \color{blue}{\frac{-23}{360}}, \frac{1}{6}\right)\right) \]
      12. lower-fma.f64N/A

        \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{-11}{15120}, \frac{-23}{360}\right)}, \frac{1}{6}\right)\right) \]
      13. unpow2N/A

        \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-11}{15120}, \frac{-23}{360}\right), \frac{1}{6}\right)\right) \]
      14. lower-*.f6499.6

        \[\leadsto x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right)\right) \]
    5. Simplified99.6%

      \[\leadsto \color{blue}{x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right)\right)} \]
    6. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto x \cdot \left(x \cdot \left(\color{blue}{\left(x \cdot x\right)} \cdot \left(\left(x \cdot x\right) \cdot \frac{-11}{15120} + \frac{-23}{360}\right) + \frac{1}{6}\right)\right) \]
      2. lift-*.f64N/A

        \[\leadsto x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \left(\color{blue}{\left(x \cdot x\right)} \cdot \frac{-11}{15120} + \frac{-23}{360}\right) + \frac{1}{6}\right)\right) \]
      3. lift-fma.f64N/A

        \[\leadsto x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \color{blue}{\mathsf{fma}\left(x \cdot x, \frac{-11}{15120}, \frac{-23}{360}\right)} + \frac{1}{6}\right)\right) \]
      4. lift-fma.f64N/A

        \[\leadsto x \cdot \left(x \cdot \color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{-11}{15120}, \frac{-23}{360}\right), \frac{1}{6}\right)}\right) \]
      5. associate-*r*N/A

        \[\leadsto \color{blue}{\left(x \cdot x\right) \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{-11}{15120}, \frac{-23}{360}\right), \frac{1}{6}\right)} \]
      6. lift-*.f64N/A

        \[\leadsto \color{blue}{\left(x \cdot x\right)} \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{-11}{15120}, \frac{-23}{360}\right), \frac{1}{6}\right) \]
      7. *-commutativeN/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{-11}{15120}, \frac{-23}{360}\right), \frac{1}{6}\right) \cdot \left(x \cdot x\right)} \]
      8. lower-*.f6499.6

        \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right) \cdot \left(x \cdot x\right)} \]
      9. lift-fma.f64N/A

        \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{\left(x \cdot x\right) \cdot \frac{-11}{15120} + \frac{-23}{360}}, \frac{1}{6}\right) \cdot \left(x \cdot x\right) \]
      10. lift-*.f64N/A

        \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{\left(x \cdot x\right)} \cdot \frac{-11}{15120} + \frac{-23}{360}, \frac{1}{6}\right) \cdot \left(x \cdot x\right) \]
      11. associate-*l*N/A

        \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{x \cdot \left(x \cdot \frac{-11}{15120}\right)} + \frac{-23}{360}, \frac{1}{6}\right) \cdot \left(x \cdot x\right) \]
      12. lower-fma.f64N/A

        \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left(x, x \cdot \frac{-11}{15120}, \frac{-23}{360}\right)}, \frac{1}{6}\right) \cdot \left(x \cdot x\right) \]
      13. lower-*.f6499.6

        \[\leadsto \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, \color{blue}{x \cdot -0.0007275132275132275}, -0.06388888888888888\right), 0.16666666666666666\right) \cdot \left(x \cdot x\right) \]
    7. Applied egg-rr99.6%

      \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right) \cdot \left(x \cdot x\right)} \]
    8. Applied egg-rr99.6%

      \[\leadsto \color{blue}{\frac{x \cdot x}{\frac{1}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot -0.0007275132275132275, -0.06388888888888888\right), 0.16666666666666666\right)}}} \]
    9. Taylor expanded in x around 0

      \[\leadsto \frac{x \cdot x}{\color{blue}{6}} \]
    10. Step-by-step derivation
      1. Simplified98.1%

        \[\leadsto \frac{x \cdot x}{\color{blue}{6}} \]
      2. Add Preprocessing

      Alternative 8: 98.9% accurate, 19.5× speedup?

      \[\begin{array}{l} \\ \left(x \cdot x\right) \cdot 0.16666666666666666 \end{array} \]
      (FPCore (x) :precision binary64 (* (* x x) 0.16666666666666666))
      double code(double x) {
      	return (x * x) * 0.16666666666666666;
      }
      
      real(8) function code(x)
          real(8), intent (in) :: x
          code = (x * x) * 0.16666666666666666d0
      end function
      
      public static double code(double x) {
      	return (x * x) * 0.16666666666666666;
      }
      
      def code(x):
      	return (x * x) * 0.16666666666666666
      
      function code(x)
      	return Float64(Float64(x * x) * 0.16666666666666666)
      end
      
      function tmp = code(x)
      	tmp = (x * x) * 0.16666666666666666;
      end
      
      code[x_] := N[(N[(x * x), $MachinePrecision] * 0.16666666666666666), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \left(x \cdot x\right) \cdot 0.16666666666666666
      \end{array}
      
      Derivation
      1. Initial program 49.3%

        \[\frac{x - \sin x}{\tan x} \]
      2. Add Preprocessing
      3. Taylor expanded in x around 0

        \[\leadsto \color{blue}{\frac{1}{6} \cdot {x}^{2}} \]
      4. Step-by-step derivation
        1. lower-*.f64N/A

          \[\leadsto \color{blue}{\frac{1}{6} \cdot {x}^{2}} \]
        2. unpow2N/A

          \[\leadsto \frac{1}{6} \cdot \color{blue}{\left(x \cdot x\right)} \]
        3. lower-*.f6498.1

          \[\leadsto 0.16666666666666666 \cdot \color{blue}{\left(x \cdot x\right)} \]
      5. Simplified98.1%

        \[\leadsto \color{blue}{0.16666666666666666 \cdot \left(x \cdot x\right)} \]
      6. Final simplification98.1%

        \[\leadsto \left(x \cdot x\right) \cdot 0.16666666666666666 \]
      7. Add Preprocessing

      Developer Target 1: 98.9% accurate, 19.5× speedup?

      \[\begin{array}{l} \\ 0.16666666666666666 \cdot \left(x \cdot x\right) \end{array} \]
      (FPCore (x) :precision binary64 (* 0.16666666666666666 (* x x)))
      double code(double x) {
      	return 0.16666666666666666 * (x * x);
      }
      
      real(8) function code(x)
          real(8), intent (in) :: x
          code = 0.16666666666666666d0 * (x * x)
      end function
      
      public static double code(double x) {
      	return 0.16666666666666666 * (x * x);
      }
      
      def code(x):
      	return 0.16666666666666666 * (x * x)
      
      function code(x)
      	return Float64(0.16666666666666666 * Float64(x * x))
      end
      
      function tmp = code(x)
      	tmp = 0.16666666666666666 * (x * x);
      end
      
      code[x_] := N[(0.16666666666666666 * N[(x * x), $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      0.16666666666666666 \cdot \left(x \cdot x\right)
      \end{array}
      

      Reproduce

      ?
      herbie shell --seed 2024207 
      (FPCore (x)
        :name "ENA, Section 1.4, Exercise 4a"
        :precision binary64
        :pre (and (<= -1.0 x) (<= x 1.0))
      
        :alt
        (! :herbie-platform default (* 1/6 (* x x)))
      
        (/ (- x (sin x)) (tan x)))