Lanczos kernel

Percentage Accurate: 97.9% → 97.9%
Time: 14.4s
Alternatives: 12
Speedup: N/A×

Specification

?
\[\left(10^{-5} \leq x \land x \leq 1\right) \land \left(1 \leq tau \land tau \leq 5\right)\]
\[\begin{array}{l} \\ \begin{array}{l} t_1 := \left(x \cdot \pi\right) \cdot tau\\ \frac{\sin t\_1}{t\_1} \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi} \end{array} \end{array} \]
(FPCore (x tau)
 :precision binary32
 (let* ((t_1 (* (* x PI) tau)))
   (* (/ (sin t_1) t_1) (/ (sin (* x PI)) (* x PI)))))
float code(float x, float tau) {
	float t_1 = (x * ((float) M_PI)) * tau;
	return (sinf(t_1) / t_1) * (sinf((x * ((float) M_PI))) / (x * ((float) M_PI)));
}
function code(x, tau)
	t_1 = Float32(Float32(x * Float32(pi)) * tau)
	return Float32(Float32(sin(t_1) / t_1) * Float32(sin(Float32(x * Float32(pi))) / Float32(x * Float32(pi))))
end
function tmp = code(x, tau)
	t_1 = (x * single(pi)) * tau;
	tmp = (sin(t_1) / t_1) * (sin((x * single(pi))) / (x * single(pi)));
end
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \left(x \cdot \pi\right) \cdot tau\\
\frac{\sin t\_1}{t\_1} \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi}
\end{array}
\end{array}

Sampling outcomes in binary32 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 12 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: 97.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \left(x \cdot \pi\right) \cdot tau\\ \frac{\sin t\_1}{t\_1} \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi} \end{array} \end{array} \]
(FPCore (x tau)
 :precision binary32
 (let* ((t_1 (* (* x PI) tau)))
   (* (/ (sin t_1) t_1) (/ (sin (* x PI)) (* x PI)))))
float code(float x, float tau) {
	float t_1 = (x * ((float) M_PI)) * tau;
	return (sinf(t_1) / t_1) * (sinf((x * ((float) M_PI))) / (x * ((float) M_PI)));
}
function code(x, tau)
	t_1 = Float32(Float32(x * Float32(pi)) * tau)
	return Float32(Float32(sin(t_1) / t_1) * Float32(sin(Float32(x * Float32(pi))) / Float32(x * Float32(pi))))
end
function tmp = code(x, tau)
	t_1 = (x * single(pi)) * tau;
	tmp = (sin(t_1) / t_1) * (sin((x * single(pi))) / (x * single(pi)));
end
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \left(x \cdot \pi\right) \cdot tau\\
\frac{\sin t\_1}{t\_1} \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi}
\end{array}
\end{array}

Alternative 1: 97.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := x \cdot \left(tau \cdot \pi\right)\\ \frac{\sin t\_1}{t\_1} \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi} \end{array} \end{array} \]
(FPCore (x tau)
 :precision binary32
 (let* ((t_1 (* x (* tau PI))))
   (* (/ (sin t_1) t_1) (/ (sin (* x PI)) (* x PI)))))
float code(float x, float tau) {
	float t_1 = x * (tau * ((float) M_PI));
	return (sinf(t_1) / t_1) * (sinf((x * ((float) M_PI))) / (x * ((float) M_PI)));
}
function code(x, tau)
	t_1 = Float32(x * Float32(tau * Float32(pi)))
	return Float32(Float32(sin(t_1) / t_1) * Float32(sin(Float32(x * Float32(pi))) / Float32(x * Float32(pi))))
end
function tmp = code(x, tau)
	t_1 = x * (tau * single(pi));
	tmp = (sin(t_1) / t_1) * (sin((x * single(pi))) / (x * single(pi)));
end
\begin{array}{l}

\\
\begin{array}{l}
t_1 := x \cdot \left(tau \cdot \pi\right)\\
\frac{\sin t\_1}{t\_1} \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi}
\end{array}
\end{array}
Derivation
  1. Initial program 97.6%

    \[\frac{\sin \left(\left(x \cdot \pi\right) \cdot tau\right)}{\left(x \cdot \pi\right) \cdot tau} \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi} \]
  2. Add Preprocessing
  3. Taylor expanded in x around inf

    \[\leadsto \color{blue}{\frac{\sin \left(tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)\right)}{tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)}} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
  4. Step-by-step derivation
    1. lower-/.f32N/A

      \[\leadsto \color{blue}{\frac{\sin \left(tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)\right)}{tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)}} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    2. lower-sin.f32N/A

      \[\leadsto \frac{\color{blue}{\sin \left(tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)\right)}}{tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    3. *-commutativeN/A

      \[\leadsto \frac{\sin \color{blue}{\left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}}{tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    4. associate-*r*N/A

      \[\leadsto \frac{\sin \color{blue}{\left(x \cdot \left(\mathsf{PI}\left(\right) \cdot tau\right)\right)}}{tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    5. *-commutativeN/A

      \[\leadsto \frac{\sin \left(x \cdot \color{blue}{\left(tau \cdot \mathsf{PI}\left(\right)\right)}\right)}{tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    6. lower-*.f32N/A

      \[\leadsto \frac{\sin \color{blue}{\left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right)}}{tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    7. lower-*.f32N/A

      \[\leadsto \frac{\sin \left(x \cdot \color{blue}{\left(tau \cdot \mathsf{PI}\left(\right)\right)}\right)}{tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    8. lower-PI.f32N/A

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \color{blue}{\mathsf{PI}\left(\right)}\right)\right)}{tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    9. *-commutativeN/A

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right)}{\color{blue}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau}} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    10. associate-*r*N/A

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right)}{\color{blue}{x \cdot \left(\mathsf{PI}\left(\right) \cdot tau\right)}} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    11. *-commutativeN/A

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right)}{x \cdot \color{blue}{\left(tau \cdot \mathsf{PI}\left(\right)\right)}} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    12. lower-*.f32N/A

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right)}{\color{blue}{x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)}} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    13. lower-*.f32N/A

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right)}{x \cdot \color{blue}{\left(tau \cdot \mathsf{PI}\left(\right)\right)}} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    14. lower-PI.f3297.7

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \pi\right)\right)}{x \cdot \left(tau \cdot \color{blue}{\pi}\right)} \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi} \]
  5. Applied rewrites97.7%

    \[\leadsto \color{blue}{\frac{\sin \left(x \cdot \left(tau \cdot \pi\right)\right)}{x \cdot \left(tau \cdot \pi\right)}} \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi} \]
  6. Add Preprocessing

Alternative 2: 97.4% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \pi \cdot \left(x \cdot tau\right)\\ \frac{\sin \left(x \cdot \pi\right) \cdot \sin t\_1}{x \cdot \left(\pi \cdot t\_1\right)} \end{array} \end{array} \]
(FPCore (x tau)
 :precision binary32
 (let* ((t_1 (* PI (* x tau))))
   (/ (* (sin (* x PI)) (sin t_1)) (* x (* PI t_1)))))
float code(float x, float tau) {
	float t_1 = ((float) M_PI) * (x * tau);
	return (sinf((x * ((float) M_PI))) * sinf(t_1)) / (x * (((float) M_PI) * t_1));
}
function code(x, tau)
	t_1 = Float32(Float32(pi) * Float32(x * tau))
	return Float32(Float32(sin(Float32(x * Float32(pi))) * sin(t_1)) / Float32(x * Float32(Float32(pi) * t_1)))
end
function tmp = code(x, tau)
	t_1 = single(pi) * (x * tau);
	tmp = (sin((x * single(pi))) * sin(t_1)) / (x * (single(pi) * t_1));
end
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \pi \cdot \left(x \cdot tau\right)\\
\frac{\sin \left(x \cdot \pi\right) \cdot \sin t\_1}{x \cdot \left(\pi \cdot t\_1\right)}
\end{array}
\end{array}
Derivation
  1. Initial program 97.6%

    \[\frac{\sin \left(\left(x \cdot \pi\right) \cdot tau\right)}{\left(x \cdot \pi\right) \cdot tau} \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-*.f32N/A

      \[\leadsto \color{blue}{\frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)}} \]
    2. lift-/.f32N/A

      \[\leadsto \color{blue}{\frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau}} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    3. lift-/.f32N/A

      \[\leadsto \frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau} \cdot \color{blue}{\frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)}} \]
    4. frac-timesN/A

      \[\leadsto \color{blue}{\frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{\left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right) \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)}} \]
    5. lower-/.f32N/A

      \[\leadsto \color{blue}{\frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{\left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right) \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)}} \]
  4. Applied rewrites97.2%

    \[\leadsto \color{blue}{\frac{\sin \left(\pi \cdot \left(x \cdot tau\right)\right) \cdot \sin \left(x \cdot \pi\right)}{x \cdot \left(\pi \cdot \left(\pi \cdot \left(x \cdot tau\right)\right)\right)}} \]
  5. Final simplification97.2%

    \[\leadsto \frac{\sin \left(x \cdot \pi\right) \cdot \sin \left(\pi \cdot \left(x \cdot tau\right)\right)}{x \cdot \left(\pi \cdot \left(\pi \cdot \left(x \cdot tau\right)\right)\right)} \]
  6. Add Preprocessing

Alternative 3: 97.4% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \sin \left(x \cdot \left(tau \cdot \pi\right)\right) \cdot \frac{\sin \left(x \cdot \pi\right)}{\left(tau \cdot \pi\right) \cdot \left(x \cdot \left(x \cdot \pi\right)\right)} \end{array} \]
(FPCore (x tau)
 :precision binary32
 (* (sin (* x (* tau PI))) (/ (sin (* x PI)) (* (* tau PI) (* x (* x PI))))))
float code(float x, float tau) {
	return sinf((x * (tau * ((float) M_PI)))) * (sinf((x * ((float) M_PI))) / ((tau * ((float) M_PI)) * (x * (x * ((float) M_PI)))));
}
function code(x, tau)
	return Float32(sin(Float32(x * Float32(tau * Float32(pi)))) * Float32(sin(Float32(x * Float32(pi))) / Float32(Float32(tau * Float32(pi)) * Float32(x * Float32(x * Float32(pi))))))
end
function tmp = code(x, tau)
	tmp = sin((x * (tau * single(pi)))) * (sin((x * single(pi))) / ((tau * single(pi)) * (x * (x * single(pi)))));
end
\begin{array}{l}

\\
\sin \left(x \cdot \left(tau \cdot \pi\right)\right) \cdot \frac{\sin \left(x \cdot \pi\right)}{\left(tau \cdot \pi\right) \cdot \left(x \cdot \left(x \cdot \pi\right)\right)}
\end{array}
Derivation
  1. Initial program 97.6%

    \[\frac{\sin \left(\left(x \cdot \pi\right) \cdot tau\right)}{\left(x \cdot \pi\right) \cdot tau} \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-*.f32N/A

      \[\leadsto \color{blue}{\frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)}} \]
    2. *-commutativeN/A

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \cdot \frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau}} \]
    3. lift-/.f32N/A

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)}} \cdot \frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau} \]
    4. div-invN/A

      \[\leadsto \color{blue}{\left(\sin \left(x \cdot \mathsf{PI}\left(\right)\right) \cdot \frac{1}{x \cdot \mathsf{PI}\left(\right)}\right)} \cdot \frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau} \]
    5. associate-*l*N/A

      \[\leadsto \color{blue}{\sin \left(x \cdot \mathsf{PI}\left(\right)\right) \cdot \left(\frac{1}{x \cdot \mathsf{PI}\left(\right)} \cdot \frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau}\right)} \]
    6. *-commutativeN/A

      \[\leadsto \color{blue}{\left(\frac{1}{x \cdot \mathsf{PI}\left(\right)} \cdot \frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau}\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)} \]
    7. lower-*.f32N/A

      \[\leadsto \color{blue}{\left(\frac{1}{x \cdot \mathsf{PI}\left(\right)} \cdot \frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau}\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)} \]
  4. Applied rewrites97.0%

    \[\leadsto \color{blue}{\frac{\sin \left(\pi \cdot \left(x \cdot tau\right)\right)}{x \cdot \left(\pi \cdot \left(\pi \cdot \left(x \cdot tau\right)\right)\right)} \cdot \sin \left(x \cdot \pi\right)} \]
  5. Step-by-step derivation
    1. lift-*.f32N/A

      \[\leadsto \color{blue}{\frac{\sin \left(\mathsf{PI}\left(\right) \cdot \left(x \cdot tau\right)\right)}{x \cdot \left(\mathsf{PI}\left(\right) \cdot \left(\mathsf{PI}\left(\right) \cdot \left(x \cdot tau\right)\right)\right)} \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)} \]
    2. lift-/.f32N/A

      \[\leadsto \color{blue}{\frac{\sin \left(\mathsf{PI}\left(\right) \cdot \left(x \cdot tau\right)\right)}{x \cdot \left(\mathsf{PI}\left(\right) \cdot \left(\mathsf{PI}\left(\right) \cdot \left(x \cdot tau\right)\right)\right)}} \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right) \]
    3. associate-*l/N/A

      \[\leadsto \color{blue}{\frac{\sin \left(\mathsf{PI}\left(\right) \cdot \left(x \cdot tau\right)\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \left(\mathsf{PI}\left(\right) \cdot \left(\mathsf{PI}\left(\right) \cdot \left(x \cdot tau\right)\right)\right)}} \]
    4. lift-*.f32N/A

      \[\leadsto \frac{\sin \left(\mathsf{PI}\left(\right) \cdot \left(x \cdot tau\right)\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{\color{blue}{x \cdot \left(\mathsf{PI}\left(\right) \cdot \left(\mathsf{PI}\left(\right) \cdot \left(x \cdot tau\right)\right)\right)}} \]
    5. lift-*.f32N/A

      \[\leadsto \frac{\sin \left(\mathsf{PI}\left(\right) \cdot \left(x \cdot tau\right)\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \color{blue}{\left(\mathsf{PI}\left(\right) \cdot \left(\mathsf{PI}\left(\right) \cdot \left(x \cdot tau\right)\right)\right)}} \]
    6. associate-*r*N/A

      \[\leadsto \frac{\sin \left(\mathsf{PI}\left(\right) \cdot \left(x \cdot tau\right)\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{\color{blue}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot \left(\mathsf{PI}\left(\right) \cdot \left(x \cdot tau\right)\right)}} \]
    7. lift-*.f32N/A

      \[\leadsto \frac{\sin \left(\mathsf{PI}\left(\right) \cdot \left(x \cdot tau\right)\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{\color{blue}{\left(x \cdot \mathsf{PI}\left(\right)\right)} \cdot \left(\mathsf{PI}\left(\right) \cdot \left(x \cdot tau\right)\right)} \]
    8. associate-/r*N/A

      \[\leadsto \color{blue}{\frac{\frac{\sin \left(\mathsf{PI}\left(\right) \cdot \left(x \cdot tau\right)\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)}}{\mathsf{PI}\left(\right) \cdot \left(x \cdot tau\right)}} \]
  6. Applied rewrites97.1%

    \[\leadsto \color{blue}{\frac{\sin \left(x \cdot \pi\right)}{\left(tau \cdot \pi\right) \cdot \left(x \cdot \left(x \cdot \pi\right)\right)} \cdot \sin \left(x \cdot \left(tau \cdot \pi\right)\right)} \]
  7. Final simplification97.1%

    \[\leadsto \sin \left(x \cdot \left(tau \cdot \pi\right)\right) \cdot \frac{\sin \left(x \cdot \pi\right)}{\left(tau \cdot \pi\right) \cdot \left(x \cdot \left(x \cdot \pi\right)\right)} \]
  8. Add Preprocessing

Alternative 4: 97.3% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \pi \cdot \left(x \cdot tau\right)\\ \sin t\_1 \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \left(\pi \cdot t\_1\right)} \end{array} \end{array} \]
(FPCore (x tau)
 :precision binary32
 (let* ((t_1 (* PI (* x tau))))
   (* (sin t_1) (/ (sin (* x PI)) (* x (* PI t_1))))))
float code(float x, float tau) {
	float t_1 = ((float) M_PI) * (x * tau);
	return sinf(t_1) * (sinf((x * ((float) M_PI))) / (x * (((float) M_PI) * t_1)));
}
function code(x, tau)
	t_1 = Float32(Float32(pi) * Float32(x * tau))
	return Float32(sin(t_1) * Float32(sin(Float32(x * Float32(pi))) / Float32(x * Float32(Float32(pi) * t_1))))
end
function tmp = code(x, tau)
	t_1 = single(pi) * (x * tau);
	tmp = sin(t_1) * (sin((x * single(pi))) / (x * (single(pi) * t_1)));
end
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \pi \cdot \left(x \cdot tau\right)\\
\sin t\_1 \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \left(\pi \cdot t\_1\right)}
\end{array}
\end{array}
Derivation
  1. Initial program 97.6%

    \[\frac{\sin \left(\left(x \cdot \pi\right) \cdot tau\right)}{\left(x \cdot \pi\right) \cdot tau} \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-*.f32N/A

      \[\leadsto \color{blue}{\frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)}} \]
    2. lift-/.f32N/A

      \[\leadsto \color{blue}{\frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau}} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    3. div-invN/A

      \[\leadsto \color{blue}{\left(\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right) \cdot \frac{1}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau}\right)} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    4. associate-*l*N/A

      \[\leadsto \color{blue}{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right) \cdot \left(\frac{1}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)}\right)} \]
    5. *-commutativeN/A

      \[\leadsto \color{blue}{\left(\frac{1}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)}\right) \cdot \sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)} \]
    6. lower-*.f32N/A

      \[\leadsto \color{blue}{\left(\frac{1}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)}\right) \cdot \sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)} \]
  4. Applied rewrites97.0%

    \[\leadsto \color{blue}{\frac{\sin \left(x \cdot \pi\right)}{x \cdot \left(\pi \cdot \left(\pi \cdot \left(x \cdot tau\right)\right)\right)} \cdot \sin \left(\pi \cdot \left(x \cdot tau\right)\right)} \]
  5. Final simplification97.0%

    \[\leadsto \sin \left(\pi \cdot \left(x \cdot tau\right)\right) \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \left(\pi \cdot \left(\pi \cdot \left(x \cdot tau\right)\right)\right)} \]
  6. Add Preprocessing

Alternative 5: 97.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{\sin \left(x \cdot \left(tau \cdot \pi\right)\right) \cdot \sin \left(x \cdot \pi\right)}{\left(x \cdot x\right) \cdot \left(tau \cdot \left(\pi \cdot \pi\right)\right)} \end{array} \]
(FPCore (x tau)
 :precision binary32
 (/ (* (sin (* x (* tau PI))) (sin (* x PI))) (* (* x x) (* tau (* PI PI)))))
float code(float x, float tau) {
	return (sinf((x * (tau * ((float) M_PI)))) * sinf((x * ((float) M_PI)))) / ((x * x) * (tau * (((float) M_PI) * ((float) M_PI))));
}
function code(x, tau)
	return Float32(Float32(sin(Float32(x * Float32(tau * Float32(pi)))) * sin(Float32(x * Float32(pi)))) / Float32(Float32(x * x) * Float32(tau * Float32(Float32(pi) * Float32(pi)))))
end
function tmp = code(x, tau)
	tmp = (sin((x * (tau * single(pi)))) * sin((x * single(pi)))) / ((x * x) * (tau * (single(pi) * single(pi))));
end
\begin{array}{l}

\\
\frac{\sin \left(x \cdot \left(tau \cdot \pi\right)\right) \cdot \sin \left(x \cdot \pi\right)}{\left(x \cdot x\right) \cdot \left(tau \cdot \left(\pi \cdot \pi\right)\right)}
\end{array}
Derivation
  1. Initial program 97.6%

    \[\frac{\sin \left(\left(x \cdot \pi\right) \cdot tau\right)}{\left(x \cdot \pi\right) \cdot tau} \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-*.f32N/A

      \[\leadsto \color{blue}{\frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)}} \]
    2. lift-/.f32N/A

      \[\leadsto \color{blue}{\frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau}} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    3. associate-*l/N/A

      \[\leadsto \color{blue}{\frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right) \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)}}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau}} \]
    4. lower-/.f32N/A

      \[\leadsto \color{blue}{\frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right) \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)}}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau}} \]
  4. Applied rewrites97.5%

    \[\leadsto \color{blue}{\frac{\sin \left(\pi \cdot \left(x \cdot tau\right)\right) \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi}}{\pi \cdot \left(x \cdot tau\right)}} \]
  5. Taylor expanded in x around 0

    \[\leadsto \frac{\color{blue}{tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)}}{\mathsf{PI}\left(\right) \cdot \left(x \cdot tau\right)} \]
  6. Step-by-step derivation
    1. lower-*.f32N/A

      \[\leadsto \frac{\color{blue}{tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)}}{\mathsf{PI}\left(\right) \cdot \left(x \cdot tau\right)} \]
    2. lower-*.f32N/A

      \[\leadsto \frac{tau \cdot \color{blue}{\left(x \cdot \mathsf{PI}\left(\right)\right)}}{\mathsf{PI}\left(\right) \cdot \left(x \cdot tau\right)} \]
    3. lower-PI.f3261.5

      \[\leadsto \frac{tau \cdot \left(x \cdot \color{blue}{\pi}\right)}{\pi \cdot \left(x \cdot tau\right)} \]
  7. Applied rewrites61.5%

    \[\leadsto \frac{\color{blue}{tau \cdot \left(x \cdot \pi\right)}}{\pi \cdot \left(x \cdot tau\right)} \]
  8. Step-by-step derivation
    1. lift-*.f32N/A

      \[\leadsto \frac{tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)}{\color{blue}{\mathsf{PI}\left(\right) \cdot \left(x \cdot tau\right)}} \]
    2. lift-*.f32N/A

      \[\leadsto \frac{tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)}{\mathsf{PI}\left(\right) \cdot \color{blue}{\left(x \cdot tau\right)}} \]
    3. *-commutativeN/A

      \[\leadsto \frac{tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)}{\mathsf{PI}\left(\right) \cdot \color{blue}{\left(tau \cdot x\right)}} \]
    4. associate-*r*N/A

      \[\leadsto \frac{tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)}{\color{blue}{\left(\mathsf{PI}\left(\right) \cdot tau\right) \cdot x}} \]
    5. lift-*.f32N/A

      \[\leadsto \frac{tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)}{\color{blue}{\left(\mathsf{PI}\left(\right) \cdot tau\right)} \cdot x} \]
    6. lower-*.f3261.5

      \[\leadsto \frac{tau \cdot \left(x \cdot \pi\right)}{\color{blue}{\left(\pi \cdot tau\right) \cdot x}} \]
  9. Applied rewrites61.5%

    \[\leadsto \frac{tau \cdot \left(x \cdot \pi\right)}{\color{blue}{\left(\pi \cdot tau\right) \cdot x}} \]
  10. Taylor expanded in x around inf

    \[\leadsto \color{blue}{\frac{\sin \left(tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{tau \cdot \left({x}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right)}} \]
  11. Step-by-step derivation
    1. *-commutativeN/A

      \[\leadsto \frac{\sin \left(tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{tau \cdot \color{blue}{\left({\mathsf{PI}\left(\right)}^{2} \cdot {x}^{2}\right)}} \]
    2. associate-*r*N/A

      \[\leadsto \frac{\sin \left(tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{\color{blue}{\left(tau \cdot {\mathsf{PI}\left(\right)}^{2}\right) \cdot {x}^{2}}} \]
    3. lower-/.f32N/A

      \[\leadsto \color{blue}{\frac{\sin \left(tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{\left(tau \cdot {\mathsf{PI}\left(\right)}^{2}\right) \cdot {x}^{2}}} \]
    4. lower-*.f32N/A

      \[\leadsto \frac{\color{blue}{\sin \left(tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)}}{\left(tau \cdot {\mathsf{PI}\left(\right)}^{2}\right) \cdot {x}^{2}} \]
    5. lower-sin.f32N/A

      \[\leadsto \frac{\color{blue}{\sin \left(tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)\right)} \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{\left(tau \cdot {\mathsf{PI}\left(\right)}^{2}\right) \cdot {x}^{2}} \]
    6. *-commutativeN/A

      \[\leadsto \frac{\sin \color{blue}{\left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)} \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{\left(tau \cdot {\mathsf{PI}\left(\right)}^{2}\right) \cdot {x}^{2}} \]
    7. associate-*r*N/A

      \[\leadsto \frac{\sin \color{blue}{\left(x \cdot \left(\mathsf{PI}\left(\right) \cdot tau\right)\right)} \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{\left(tau \cdot {\mathsf{PI}\left(\right)}^{2}\right) \cdot {x}^{2}} \]
    8. *-commutativeN/A

      \[\leadsto \frac{\sin \left(x \cdot \color{blue}{\left(tau \cdot \mathsf{PI}\left(\right)\right)}\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{\left(tau \cdot {\mathsf{PI}\left(\right)}^{2}\right) \cdot {x}^{2}} \]
    9. lower-*.f32N/A

      \[\leadsto \frac{\sin \color{blue}{\left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right)} \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{\left(tau \cdot {\mathsf{PI}\left(\right)}^{2}\right) \cdot {x}^{2}} \]
    10. lower-*.f32N/A

      \[\leadsto \frac{\sin \left(x \cdot \color{blue}{\left(tau \cdot \mathsf{PI}\left(\right)\right)}\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{\left(tau \cdot {\mathsf{PI}\left(\right)}^{2}\right) \cdot {x}^{2}} \]
    11. lower-PI.f32N/A

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \color{blue}{\mathsf{PI}\left(\right)}\right)\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{\left(tau \cdot {\mathsf{PI}\left(\right)}^{2}\right) \cdot {x}^{2}} \]
    12. lower-sin.f32N/A

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right) \cdot \color{blue}{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}}{\left(tau \cdot {\mathsf{PI}\left(\right)}^{2}\right) \cdot {x}^{2}} \]
    13. lower-*.f32N/A

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right) \cdot \sin \color{blue}{\left(x \cdot \mathsf{PI}\left(\right)\right)}}{\left(tau \cdot {\mathsf{PI}\left(\right)}^{2}\right) \cdot {x}^{2}} \]
    14. lower-PI.f32N/A

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right) \cdot \sin \left(x \cdot \color{blue}{\mathsf{PI}\left(\right)}\right)}{\left(tau \cdot {\mathsf{PI}\left(\right)}^{2}\right) \cdot {x}^{2}} \]
  12. Applied rewrites96.9%

    \[\leadsto \color{blue}{\frac{\sin \left(x \cdot \left(tau \cdot \pi\right)\right) \cdot \sin \left(x \cdot \pi\right)}{\left(x \cdot x\right) \cdot \left(tau \cdot \left(\pi \cdot \pi\right)\right)}} \]
  13. Add Preprocessing

Alternative 6: 97.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \sin \left(x \cdot \left(tau \cdot \pi\right)\right) \cdot \frac{\sin \left(x \cdot \pi\right)}{\pi \cdot \left(\pi \cdot \left(tau \cdot \left(x \cdot x\right)\right)\right)} \end{array} \]
(FPCore (x tau)
 :precision binary32
 (* (sin (* x (* tau PI))) (/ (sin (* x PI)) (* PI (* PI (* tau (* x x)))))))
float code(float x, float tau) {
	return sinf((x * (tau * ((float) M_PI)))) * (sinf((x * ((float) M_PI))) / (((float) M_PI) * (((float) M_PI) * (tau * (x * x)))));
}
function code(x, tau)
	return Float32(sin(Float32(x * Float32(tau * Float32(pi)))) * Float32(sin(Float32(x * Float32(pi))) / Float32(Float32(pi) * Float32(Float32(pi) * Float32(tau * Float32(x * x))))))
end
function tmp = code(x, tau)
	tmp = sin((x * (tau * single(pi)))) * (sin((x * single(pi))) / (single(pi) * (single(pi) * (tau * (x * x)))));
end
\begin{array}{l}

\\
\sin \left(x \cdot \left(tau \cdot \pi\right)\right) \cdot \frac{\sin \left(x \cdot \pi\right)}{\pi \cdot \left(\pi \cdot \left(tau \cdot \left(x \cdot x\right)\right)\right)}
\end{array}
Derivation
  1. Initial program 97.6%

    \[\frac{\sin \left(\left(x \cdot \pi\right) \cdot tau\right)}{\left(x \cdot \pi\right) \cdot tau} \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi} \]
  2. Add Preprocessing
  3. Taylor expanded in x around inf

    \[\leadsto \color{blue}{\frac{\sin \left(tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{tau \cdot \left({x}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right)}} \]
  4. Step-by-step derivation
    1. associate-/l*N/A

      \[\leadsto \color{blue}{\sin \left(tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)\right) \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{tau \cdot \left({x}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right)}} \]
    2. lower-*.f32N/A

      \[\leadsto \color{blue}{\sin \left(tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)\right) \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{tau \cdot \left({x}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right)}} \]
    3. lower-sin.f32N/A

      \[\leadsto \color{blue}{\sin \left(tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)\right)} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{tau \cdot \left({x}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right)} \]
    4. *-commutativeN/A

      \[\leadsto \sin \color{blue}{\left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{tau \cdot \left({x}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right)} \]
    5. associate-*r*N/A

      \[\leadsto \sin \color{blue}{\left(x \cdot \left(\mathsf{PI}\left(\right) \cdot tau\right)\right)} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{tau \cdot \left({x}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right)} \]
    6. *-commutativeN/A

      \[\leadsto \sin \left(x \cdot \color{blue}{\left(tau \cdot \mathsf{PI}\left(\right)\right)}\right) \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{tau \cdot \left({x}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right)} \]
    7. lower-*.f32N/A

      \[\leadsto \sin \color{blue}{\left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right)} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{tau \cdot \left({x}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right)} \]
    8. lower-*.f32N/A

      \[\leadsto \sin \left(x \cdot \color{blue}{\left(tau \cdot \mathsf{PI}\left(\right)\right)}\right) \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{tau \cdot \left({x}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right)} \]
    9. lower-PI.f32N/A

      \[\leadsto \sin \left(x \cdot \left(tau \cdot \color{blue}{\mathsf{PI}\left(\right)}\right)\right) \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{tau \cdot \left({x}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right)} \]
    10. associate-*r*N/A

      \[\leadsto \sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right) \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{\color{blue}{\left(tau \cdot {x}^{2}\right) \cdot {\mathsf{PI}\left(\right)}^{2}}} \]
    11. unpow2N/A

      \[\leadsto \sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right) \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{\left(tau \cdot {x}^{2}\right) \cdot \color{blue}{\left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right)}} \]
    12. associate-*r*N/A

      \[\leadsto \sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right) \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{\color{blue}{\left(\left(tau \cdot {x}^{2}\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \mathsf{PI}\left(\right)}} \]
    13. associate-/r*N/A

      \[\leadsto \sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right) \cdot \color{blue}{\frac{\frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{\left(tau \cdot {x}^{2}\right) \cdot \mathsf{PI}\left(\right)}}{\mathsf{PI}\left(\right)}} \]
    14. associate-/l/N/A

      \[\leadsto \sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right) \cdot \color{blue}{\frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{\mathsf{PI}\left(\right) \cdot \left(\left(tau \cdot {x}^{2}\right) \cdot \mathsf{PI}\left(\right)\right)}} \]
    15. lower-/.f32N/A

      \[\leadsto \sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right) \cdot \color{blue}{\frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{\mathsf{PI}\left(\right) \cdot \left(\left(tau \cdot {x}^{2}\right) \cdot \mathsf{PI}\left(\right)\right)}} \]
  5. Applied rewrites96.7%

    \[\leadsto \color{blue}{\sin \left(x \cdot \left(tau \cdot \pi\right)\right) \cdot \frac{\sin \left(x \cdot \pi\right)}{\pi \cdot \left(\left(\left(x \cdot x\right) \cdot tau\right) \cdot \pi\right)}} \]
  6. Final simplification96.7%

    \[\leadsto \sin \left(x \cdot \left(tau \cdot \pi\right)\right) \cdot \frac{\sin \left(x \cdot \pi\right)}{\pi \cdot \left(\pi \cdot \left(tau \cdot \left(x \cdot x\right)\right)\right)} \]
  7. Add Preprocessing

Alternative 7: 90.3% accurate, 1.2× speedup?

\[\begin{array}{l} \\ \frac{\sin \left(\pi \cdot \left(x \cdot tau\right)\right)}{-x} \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{\left(\pi \cdot \left(\pi \cdot \pi\right)\right) \cdot -0.008333333333333333}{tau}, \frac{\pi \cdot 0.16666666666666666}{tau}\right), \frac{-1}{tau \cdot \pi}\right) \end{array} \]
(FPCore (x tau)
 :precision binary32
 (*
  (/ (sin (* PI (* x tau))) (- x))
  (fma
   (* x x)
   (fma
    (* x x)
    (/ (* (* PI (* PI PI)) -0.008333333333333333) tau)
    (/ (* PI 0.16666666666666666) tau))
   (/ -1.0 (* tau PI)))))
float code(float x, float tau) {
	return (sinf((((float) M_PI) * (x * tau))) / -x) * fmaf((x * x), fmaf((x * x), (((((float) M_PI) * (((float) M_PI) * ((float) M_PI))) * -0.008333333333333333f) / tau), ((((float) M_PI) * 0.16666666666666666f) / tau)), (-1.0f / (tau * ((float) M_PI))));
}
function code(x, tau)
	return Float32(Float32(sin(Float32(Float32(pi) * Float32(x * tau))) / Float32(-x)) * fma(Float32(x * x), fma(Float32(x * x), Float32(Float32(Float32(Float32(pi) * Float32(Float32(pi) * Float32(pi))) * Float32(-0.008333333333333333)) / tau), Float32(Float32(Float32(pi) * Float32(0.16666666666666666)) / tau)), Float32(Float32(-1.0) / Float32(tau * Float32(pi)))))
end
\begin{array}{l}

\\
\frac{\sin \left(\pi \cdot \left(x \cdot tau\right)\right)}{-x} \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{\left(\pi \cdot \left(\pi \cdot \pi\right)\right) \cdot -0.008333333333333333}{tau}, \frac{\pi \cdot 0.16666666666666666}{tau}\right), \frac{-1}{tau \cdot \pi}\right)
\end{array}
Derivation
  1. Initial program 97.6%

    \[\frac{\sin \left(\left(x \cdot \pi\right) \cdot tau\right)}{\left(x \cdot \pi\right) \cdot tau} \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-*.f32N/A

      \[\leadsto \color{blue}{\frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)}} \]
    2. lift-/.f32N/A

      \[\leadsto \color{blue}{\frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau}} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    3. frac-2negN/A

      \[\leadsto \color{blue}{\frac{\mathsf{neg}\left(\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)\right)}{\mathsf{neg}\left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    4. associate-*l/N/A

      \[\leadsto \color{blue}{\frac{\left(\mathsf{neg}\left(\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)\right)\right) \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)}}{\mathsf{neg}\left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}} \]
    5. lift-*.f32N/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)\right)\right) \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)}}{\mathsf{neg}\left(\color{blue}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau}\right)} \]
    6. lift-*.f32N/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)\right)\right) \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)}}{\mathsf{neg}\left(\color{blue}{\left(x \cdot \mathsf{PI}\left(\right)\right)} \cdot tau\right)} \]
    7. associate-*l*N/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)\right)\right) \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)}}{\mathsf{neg}\left(\color{blue}{x \cdot \left(\mathsf{PI}\left(\right) \cdot tau\right)}\right)} \]
    8. distribute-rgt-neg-inN/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)\right)\right) \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)}}{\color{blue}{x \cdot \left(\mathsf{neg}\left(\mathsf{PI}\left(\right) \cdot tau\right)\right)}} \]
    9. times-fracN/A

      \[\leadsto \color{blue}{\frac{\mathsf{neg}\left(\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)\right)}{x} \cdot \frac{\frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)}}{\mathsf{neg}\left(\mathsf{PI}\left(\right) \cdot tau\right)}} \]
    10. lower-*.f32N/A

      \[\leadsto \color{blue}{\frac{\mathsf{neg}\left(\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)\right)}{x} \cdot \frac{\frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)}}{\mathsf{neg}\left(\mathsf{PI}\left(\right) \cdot tau\right)}} \]
  4. Applied rewrites97.1%

    \[\leadsto \color{blue}{\frac{-\sin \left(\pi \cdot \left(x \cdot tau\right)\right)}{x} \cdot \frac{\frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi}}{\pi \cdot \left(-tau\right)}} \]
  5. Taylor expanded in x around 0

    \[\leadsto \frac{\mathsf{neg}\left(\sin \left(\mathsf{PI}\left(\right) \cdot \left(x \cdot tau\right)\right)\right)}{x} \cdot \color{blue}{\left({x}^{2} \cdot \left(\frac{-1}{120} \cdot \frac{{x}^{2} \cdot {\mathsf{PI}\left(\right)}^{3}}{tau} + \frac{1}{6} \cdot \frac{\mathsf{PI}\left(\right)}{tau}\right) - \frac{1}{tau \cdot \mathsf{PI}\left(\right)}\right)} \]
  6. Step-by-step derivation
    1. sub-negN/A

      \[\leadsto \frac{\mathsf{neg}\left(\sin \left(\mathsf{PI}\left(\right) \cdot \left(x \cdot tau\right)\right)\right)}{x} \cdot \color{blue}{\left({x}^{2} \cdot \left(\frac{-1}{120} \cdot \frac{{x}^{2} \cdot {\mathsf{PI}\left(\right)}^{3}}{tau} + \frac{1}{6} \cdot \frac{\mathsf{PI}\left(\right)}{tau}\right) + \left(\mathsf{neg}\left(\frac{1}{tau \cdot \mathsf{PI}\left(\right)}\right)\right)\right)} \]
    2. lower-fma.f32N/A

      \[\leadsto \frac{\mathsf{neg}\left(\sin \left(\mathsf{PI}\left(\right) \cdot \left(x \cdot tau\right)\right)\right)}{x} \cdot \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{-1}{120} \cdot \frac{{x}^{2} \cdot {\mathsf{PI}\left(\right)}^{3}}{tau} + \frac{1}{6} \cdot \frac{\mathsf{PI}\left(\right)}{tau}, \mathsf{neg}\left(\frac{1}{tau \cdot \mathsf{PI}\left(\right)}\right)\right)} \]
  7. Applied rewrites89.7%

    \[\leadsto \frac{-\sin \left(\pi \cdot \left(x \cdot tau\right)\right)}{x} \cdot \color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{\left(\pi \cdot \left(\pi \cdot \pi\right)\right) \cdot -0.008333333333333333}{tau}, \frac{\pi \cdot 0.16666666666666666}{tau}\right), \frac{-1}{tau \cdot \pi}\right)} \]
  8. Final simplification89.7%

    \[\leadsto \frac{\sin \left(\pi \cdot \left(x \cdot tau\right)\right)}{-x} \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{\left(\pi \cdot \left(\pi \cdot \pi\right)\right) \cdot -0.008333333333333333}{tau}, \frac{\pi \cdot 0.16666666666666666}{tau}\right), \frac{-1}{tau \cdot \pi}\right) \]
  9. Add Preprocessing

Alternative 8: 84.8% accurate, 1.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := x \cdot \left(tau \cdot \pi\right)\\ \frac{\sin t\_1}{t\_1} \cdot \mathsf{fma}\left(\pi \cdot \pi, \left(x \cdot x\right) \cdot -0.16666666666666666, 1\right) \end{array} \end{array} \]
(FPCore (x tau)
 :precision binary32
 (let* ((t_1 (* x (* tau PI))))
   (* (/ (sin t_1) t_1) (fma (* PI PI) (* (* x x) -0.16666666666666666) 1.0))))
float code(float x, float tau) {
	float t_1 = x * (tau * ((float) M_PI));
	return (sinf(t_1) / t_1) * fmaf((((float) M_PI) * ((float) M_PI)), ((x * x) * -0.16666666666666666f), 1.0f);
}
function code(x, tau)
	t_1 = Float32(x * Float32(tau * Float32(pi)))
	return Float32(Float32(sin(t_1) / t_1) * fma(Float32(Float32(pi) * Float32(pi)), Float32(Float32(x * x) * Float32(-0.16666666666666666)), Float32(1.0)))
end
\begin{array}{l}

\\
\begin{array}{l}
t_1 := x \cdot \left(tau \cdot \pi\right)\\
\frac{\sin t\_1}{t\_1} \cdot \mathsf{fma}\left(\pi \cdot \pi, \left(x \cdot x\right) \cdot -0.16666666666666666, 1\right)
\end{array}
\end{array}
Derivation
  1. Initial program 97.6%

    \[\frac{\sin \left(\left(x \cdot \pi\right) \cdot tau\right)}{\left(x \cdot \pi\right) \cdot tau} \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi} \]
  2. Add Preprocessing
  3. Taylor expanded in x around inf

    \[\leadsto \color{blue}{\frac{\sin \left(tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)\right)}{tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)}} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
  4. Step-by-step derivation
    1. lower-/.f32N/A

      \[\leadsto \color{blue}{\frac{\sin \left(tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)\right)}{tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)}} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    2. lower-sin.f32N/A

      \[\leadsto \frac{\color{blue}{\sin \left(tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)\right)}}{tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    3. *-commutativeN/A

      \[\leadsto \frac{\sin \color{blue}{\left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}}{tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    4. associate-*r*N/A

      \[\leadsto \frac{\sin \color{blue}{\left(x \cdot \left(\mathsf{PI}\left(\right) \cdot tau\right)\right)}}{tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    5. *-commutativeN/A

      \[\leadsto \frac{\sin \left(x \cdot \color{blue}{\left(tau \cdot \mathsf{PI}\left(\right)\right)}\right)}{tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    6. lower-*.f32N/A

      \[\leadsto \frac{\sin \color{blue}{\left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right)}}{tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    7. lower-*.f32N/A

      \[\leadsto \frac{\sin \left(x \cdot \color{blue}{\left(tau \cdot \mathsf{PI}\left(\right)\right)}\right)}{tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    8. lower-PI.f32N/A

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \color{blue}{\mathsf{PI}\left(\right)}\right)\right)}{tau \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    9. *-commutativeN/A

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right)}{\color{blue}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau}} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    10. associate-*r*N/A

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right)}{\color{blue}{x \cdot \left(\mathsf{PI}\left(\right) \cdot tau\right)}} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    11. *-commutativeN/A

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right)}{x \cdot \color{blue}{\left(tau \cdot \mathsf{PI}\left(\right)\right)}} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    12. lower-*.f32N/A

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right)}{\color{blue}{x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)}} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    13. lower-*.f32N/A

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right)}{x \cdot \color{blue}{\left(tau \cdot \mathsf{PI}\left(\right)\right)}} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \]
    14. lower-PI.f3297.7

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \pi\right)\right)}{x \cdot \left(tau \cdot \color{blue}{\pi}\right)} \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi} \]
  5. Applied rewrites97.7%

    \[\leadsto \color{blue}{\frac{\sin \left(x \cdot \left(tau \cdot \pi\right)\right)}{x \cdot \left(tau \cdot \pi\right)}} \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi} \]
  6. Taylor expanded in x around 0

    \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right)}{x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)} \cdot \color{blue}{\left(1 + \frac{-1}{6} \cdot \left({x}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right)\right)} \]
  7. Step-by-step derivation
    1. *-commutativeN/A

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right)}{x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)} \cdot \left(1 + \frac{-1}{6} \cdot \color{blue}{\left({\mathsf{PI}\left(\right)}^{2} \cdot {x}^{2}\right)}\right) \]
    2. associate-*r*N/A

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right)}{x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)} \cdot \left(1 + \color{blue}{\left(\frac{-1}{6} \cdot {\mathsf{PI}\left(\right)}^{2}\right) \cdot {x}^{2}}\right) \]
    3. +-commutativeN/A

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right)}{x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)} \cdot \color{blue}{\left(\left(\frac{-1}{6} \cdot {\mathsf{PI}\left(\right)}^{2}\right) \cdot {x}^{2} + 1\right)} \]
    4. *-commutativeN/A

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

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right)}{x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)} \cdot \left(\color{blue}{{\mathsf{PI}\left(\right)}^{2} \cdot \left(\frac{-1}{6} \cdot {x}^{2}\right)} + 1\right) \]
    6. lower-fma.f32N/A

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

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right)}{x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)} \cdot \mathsf{fma}\left(\color{blue}{\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)}, \frac{-1}{6} \cdot {x}^{2}, 1\right) \]
    8. lower-*.f32N/A

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right)}{x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)} \cdot \mathsf{fma}\left(\color{blue}{\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)}, \frac{-1}{6} \cdot {x}^{2}, 1\right) \]
    9. lower-PI.f32N/A

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right)}{x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)} \cdot \mathsf{fma}\left(\color{blue}{\mathsf{PI}\left(\right)} \cdot \mathsf{PI}\left(\right), \frac{-1}{6} \cdot {x}^{2}, 1\right) \]
    10. lower-PI.f32N/A

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right)}{x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)} \cdot \mathsf{fma}\left(\mathsf{PI}\left(\right) \cdot \color{blue}{\mathsf{PI}\left(\right)}, \frac{-1}{6} \cdot {x}^{2}, 1\right) \]
    11. *-commutativeN/A

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right)}{x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)} \cdot \mathsf{fma}\left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right), \color{blue}{{x}^{2} \cdot \frac{-1}{6}}, 1\right) \]
    12. lower-*.f32N/A

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

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)\right)}{x \cdot \left(tau \cdot \mathsf{PI}\left(\right)\right)} \cdot \mathsf{fma}\left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right), \color{blue}{\left(x \cdot x\right)} \cdot \frac{-1}{6}, 1\right) \]
    14. lower-*.f3284.5

      \[\leadsto \frac{\sin \left(x \cdot \left(tau \cdot \pi\right)\right)}{x \cdot \left(tau \cdot \pi\right)} \cdot \mathsf{fma}\left(\pi \cdot \pi, \color{blue}{\left(x \cdot x\right)} \cdot -0.16666666666666666, 1\right) \]
  8. Applied rewrites84.5%

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

Alternative 9: 78.8% accurate, 1.7× speedup?

\[\begin{array}{l} \\ \sin \left(x \cdot \pi\right) \cdot \mathsf{fma}\left(\pi \cdot \left(-0.16666666666666666 \cdot \left(tau \cdot tau\right)\right), x, \frac{1}{x \cdot \pi}\right) \end{array} \]
(FPCore (x tau)
 :precision binary32
 (*
  (sin (* x PI))
  (fma (* PI (* -0.16666666666666666 (* tau tau))) x (/ 1.0 (* x PI)))))
float code(float x, float tau) {
	return sinf((x * ((float) M_PI))) * fmaf((((float) M_PI) * (-0.16666666666666666f * (tau * tau))), x, (1.0f / (x * ((float) M_PI))));
}
function code(x, tau)
	return Float32(sin(Float32(x * Float32(pi))) * fma(Float32(Float32(pi) * Float32(Float32(-0.16666666666666666) * Float32(tau * tau))), x, Float32(Float32(1.0) / Float32(x * Float32(pi)))))
end
\begin{array}{l}

\\
\sin \left(x \cdot \pi\right) \cdot \mathsf{fma}\left(\pi \cdot \left(-0.16666666666666666 \cdot \left(tau \cdot tau\right)\right), x, \frac{1}{x \cdot \pi}\right)
\end{array}
Derivation
  1. Initial program 97.6%

    \[\frac{\sin \left(\left(x \cdot \pi\right) \cdot tau\right)}{\left(x \cdot \pi\right) \cdot tau} \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-*.f32N/A

      \[\leadsto \color{blue}{\frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)}} \]
    2. *-commutativeN/A

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \cdot \frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau}} \]
    3. lift-/.f32N/A

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)}} \cdot \frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau} \]
    4. div-invN/A

      \[\leadsto \color{blue}{\left(\sin \left(x \cdot \mathsf{PI}\left(\right)\right) \cdot \frac{1}{x \cdot \mathsf{PI}\left(\right)}\right)} \cdot \frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau} \]
    5. associate-*l*N/A

      \[\leadsto \color{blue}{\sin \left(x \cdot \mathsf{PI}\left(\right)\right) \cdot \left(\frac{1}{x \cdot \mathsf{PI}\left(\right)} \cdot \frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau}\right)} \]
    6. *-commutativeN/A

      \[\leadsto \color{blue}{\left(\frac{1}{x \cdot \mathsf{PI}\left(\right)} \cdot \frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau}\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)} \]
    7. lower-*.f32N/A

      \[\leadsto \color{blue}{\left(\frac{1}{x \cdot \mathsf{PI}\left(\right)} \cdot \frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau}\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)} \]
  4. Applied rewrites97.0%

    \[\leadsto \color{blue}{\frac{\sin \left(\pi \cdot \left(x \cdot tau\right)\right)}{x \cdot \left(\pi \cdot \left(\pi \cdot \left(x \cdot tau\right)\right)\right)} \cdot \sin \left(x \cdot \pi\right)} \]
  5. Taylor expanded in tau around 0

    \[\leadsto \color{blue}{\left(\frac{-1}{6} \cdot \left({tau}^{2} \cdot \left(x \cdot \mathsf{PI}\left(\right)\right)\right) + \frac{1}{x \cdot \mathsf{PI}\left(\right)}\right)} \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right) \]
  6. Step-by-step derivation
    1. associate-*r*N/A

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

      \[\leadsto \left(\left(\frac{-1}{6} \cdot {tau}^{2}\right) \cdot \color{blue}{\left(\mathsf{PI}\left(\right) \cdot x\right)} + \frac{1}{x \cdot \mathsf{PI}\left(\right)}\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right) \]
    3. associate-*r*N/A

      \[\leadsto \left(\color{blue}{\left(\left(\frac{-1}{6} \cdot {tau}^{2}\right) \cdot \mathsf{PI}\left(\right)\right) \cdot x} + \frac{1}{x \cdot \mathsf{PI}\left(\right)}\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right) \]
    4. associate-*r*N/A

      \[\leadsto \left(\color{blue}{\left(\frac{-1}{6} \cdot \left({tau}^{2} \cdot \mathsf{PI}\left(\right)\right)\right)} \cdot x + \frac{1}{x \cdot \mathsf{PI}\left(\right)}\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right) \]
    5. lower-fma.f32N/A

      \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{-1}{6} \cdot \left({tau}^{2} \cdot \mathsf{PI}\left(\right)\right), x, \frac{1}{x \cdot \mathsf{PI}\left(\right)}\right)} \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right) \]
    6. associate-*r*N/A

      \[\leadsto \mathsf{fma}\left(\color{blue}{\left(\frac{-1}{6} \cdot {tau}^{2}\right) \cdot \mathsf{PI}\left(\right)}, x, \frac{1}{x \cdot \mathsf{PI}\left(\right)}\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right) \]
    7. *-commutativeN/A

      \[\leadsto \mathsf{fma}\left(\color{blue}{\mathsf{PI}\left(\right) \cdot \left(\frac{-1}{6} \cdot {tau}^{2}\right)}, x, \frac{1}{x \cdot \mathsf{PI}\left(\right)}\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right) \]
    8. lower-*.f32N/A

      \[\leadsto \mathsf{fma}\left(\color{blue}{\mathsf{PI}\left(\right) \cdot \left(\frac{-1}{6} \cdot {tau}^{2}\right)}, x, \frac{1}{x \cdot \mathsf{PI}\left(\right)}\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right) \]
    9. lower-PI.f32N/A

      \[\leadsto \mathsf{fma}\left(\color{blue}{\mathsf{PI}\left(\right)} \cdot \left(\frac{-1}{6} \cdot {tau}^{2}\right), x, \frac{1}{x \cdot \mathsf{PI}\left(\right)}\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right) \]
    10. lower-*.f32N/A

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

      \[\leadsto \mathsf{fma}\left(\mathsf{PI}\left(\right) \cdot \left(\frac{-1}{6} \cdot \color{blue}{\left(tau \cdot tau\right)}\right), x, \frac{1}{x \cdot \mathsf{PI}\left(\right)}\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right) \]
    12. lower-*.f32N/A

      \[\leadsto \mathsf{fma}\left(\mathsf{PI}\left(\right) \cdot \left(\frac{-1}{6} \cdot \color{blue}{\left(tau \cdot tau\right)}\right), x, \frac{1}{x \cdot \mathsf{PI}\left(\right)}\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right) \]
    13. lower-/.f32N/A

      \[\leadsto \mathsf{fma}\left(\mathsf{PI}\left(\right) \cdot \left(\frac{-1}{6} \cdot \left(tau \cdot tau\right)\right), x, \color{blue}{\frac{1}{x \cdot \mathsf{PI}\left(\right)}}\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right) \]
    14. lower-*.f32N/A

      \[\leadsto \mathsf{fma}\left(\mathsf{PI}\left(\right) \cdot \left(\frac{-1}{6} \cdot \left(tau \cdot tau\right)\right), x, \frac{1}{\color{blue}{x \cdot \mathsf{PI}\left(\right)}}\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right) \]
    15. lower-PI.f3277.9

      \[\leadsto \mathsf{fma}\left(\pi \cdot \left(-0.16666666666666666 \cdot \left(tau \cdot tau\right)\right), x, \frac{1}{x \cdot \color{blue}{\pi}}\right) \cdot \sin \left(x \cdot \pi\right) \]
  7. Applied rewrites77.9%

    \[\leadsto \color{blue}{\mathsf{fma}\left(\pi \cdot \left(-0.16666666666666666 \cdot \left(tau \cdot tau\right)\right), x, \frac{1}{x \cdot \pi}\right)} \cdot \sin \left(x \cdot \pi\right) \]
  8. Final simplification77.9%

    \[\leadsto \sin \left(x \cdot \pi\right) \cdot \mathsf{fma}\left(\pi \cdot \left(-0.16666666666666666 \cdot \left(tau \cdot tau\right)\right), x, \frac{1}{x \cdot \pi}\right) \]
  9. Add Preprocessing

Alternative 10: 78.1% accurate, 7.8× speedup?

\[\begin{array}{l} \\ \mathsf{fma}\left(x \cdot x, \left(\pi \cdot \pi\right) \cdot \mathsf{fma}\left(-0.16666666666666666, tau \cdot tau, -0.16666666666666666\right), 1\right) \end{array} \]
(FPCore (x tau)
 :precision binary32
 (fma
  (* x x)
  (* (* PI PI) (fma -0.16666666666666666 (* tau tau) -0.16666666666666666))
  1.0))
float code(float x, float tau) {
	return fmaf((x * x), ((((float) M_PI) * ((float) M_PI)) * fmaf(-0.16666666666666666f, (tau * tau), -0.16666666666666666f)), 1.0f);
}
function code(x, tau)
	return fma(Float32(x * x), Float32(Float32(Float32(pi) * Float32(pi)) * fma(Float32(-0.16666666666666666), Float32(tau * tau), Float32(-0.16666666666666666))), Float32(1.0))
end
\begin{array}{l}

\\
\mathsf{fma}\left(x \cdot x, \left(\pi \cdot \pi\right) \cdot \mathsf{fma}\left(-0.16666666666666666, tau \cdot tau, -0.16666666666666666\right), 1\right)
\end{array}
Derivation
  1. Initial program 97.6%

    \[\frac{\sin \left(\left(x \cdot \pi\right) \cdot tau\right)}{\left(x \cdot \pi\right) \cdot tau} \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi} \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0

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

      \[\leadsto \color{blue}{{x}^{2} \cdot \left(\frac{-1}{6} \cdot \left({tau}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{-1}{6} \cdot {\mathsf{PI}\left(\right)}^{2}\right) + 1} \]
    2. lower-fma.f32N/A

      \[\leadsto \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{-1}{6} \cdot \left({tau}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{-1}{6} \cdot {\mathsf{PI}\left(\right)}^{2}, 1\right)} \]
    3. unpow2N/A

      \[\leadsto \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-1}{6} \cdot \left({tau}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{-1}{6} \cdot {\mathsf{PI}\left(\right)}^{2}, 1\right) \]
    4. lower-*.f32N/A

      \[\leadsto \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-1}{6} \cdot \left({tau}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{-1}{6} \cdot {\mathsf{PI}\left(\right)}^{2}, 1\right) \]
    5. +-commutativeN/A

      \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{\frac{-1}{6} \cdot {\mathsf{PI}\left(\right)}^{2} + \frac{-1}{6} \cdot \left({tau}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right)}, 1\right) \]
    6. associate-*r*N/A

      \[\leadsto \mathsf{fma}\left(x \cdot x, \frac{-1}{6} \cdot {\mathsf{PI}\left(\right)}^{2} + \color{blue}{\left(\frac{-1}{6} \cdot {tau}^{2}\right) \cdot {\mathsf{PI}\left(\right)}^{2}}, 1\right) \]
    7. distribute-rgt-outN/A

      \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{{\mathsf{PI}\left(\right)}^{2} \cdot \left(\frac{-1}{6} + \frac{-1}{6} \cdot {tau}^{2}\right)}, 1\right) \]
    8. lower-*.f32N/A

      \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{{\mathsf{PI}\left(\right)}^{2} \cdot \left(\frac{-1}{6} + \frac{-1}{6} \cdot {tau}^{2}\right)}, 1\right) \]
    9. unpow2N/A

      \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{\left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right)} \cdot \left(\frac{-1}{6} + \frac{-1}{6} \cdot {tau}^{2}\right), 1\right) \]
    10. lower-*.f32N/A

      \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{\left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right)} \cdot \left(\frac{-1}{6} + \frac{-1}{6} \cdot {tau}^{2}\right), 1\right) \]
    11. lower-PI.f32N/A

      \[\leadsto \mathsf{fma}\left(x \cdot x, \left(\color{blue}{\mathsf{PI}\left(\right)} \cdot \mathsf{PI}\left(\right)\right) \cdot \left(\frac{-1}{6} + \frac{-1}{6} \cdot {tau}^{2}\right), 1\right) \]
    12. lower-PI.f32N/A

      \[\leadsto \mathsf{fma}\left(x \cdot x, \left(\mathsf{PI}\left(\right) \cdot \color{blue}{\mathsf{PI}\left(\right)}\right) \cdot \left(\frac{-1}{6} + \frac{-1}{6} \cdot {tau}^{2}\right), 1\right) \]
    13. +-commutativeN/A

      \[\leadsto \mathsf{fma}\left(x \cdot x, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \color{blue}{\left(\frac{-1}{6} \cdot {tau}^{2} + \frac{-1}{6}\right)}, 1\right) \]
    14. lower-fma.f32N/A

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

      \[\leadsto \mathsf{fma}\left(x \cdot x, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \mathsf{fma}\left(\frac{-1}{6}, \color{blue}{tau \cdot tau}, \frac{-1}{6}\right), 1\right) \]
    16. lower-*.f3277.6

      \[\leadsto \mathsf{fma}\left(x \cdot x, \left(\pi \cdot \pi\right) \cdot \mathsf{fma}\left(-0.16666666666666666, \color{blue}{tau \cdot tau}, -0.16666666666666666\right), 1\right) \]
  5. Applied rewrites77.6%

    \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot x, \left(\pi \cdot \pi\right) \cdot \mathsf{fma}\left(-0.16666666666666666, tau \cdot tau, -0.16666666666666666\right), 1\right)} \]
  6. Add Preprocessing

Alternative 11: 62.8% accurate, 9.6× speedup?

\[\begin{array}{l} \\ \frac{1}{x \cdot \pi} \cdot \left(x \cdot \pi\right) \end{array} \]
(FPCore (x tau) :precision binary32 (* (/ 1.0 (* x PI)) (* x PI)))
float code(float x, float tau) {
	return (1.0f / (x * ((float) M_PI))) * (x * ((float) M_PI));
}
function code(x, tau)
	return Float32(Float32(Float32(1.0) / Float32(x * Float32(pi))) * Float32(x * Float32(pi)))
end
function tmp = code(x, tau)
	tmp = (single(1.0) / (x * single(pi))) * (x * single(pi));
end
\begin{array}{l}

\\
\frac{1}{x \cdot \pi} \cdot \left(x \cdot \pi\right)
\end{array}
Derivation
  1. Initial program 97.6%

    \[\frac{\sin \left(\left(x \cdot \pi\right) \cdot tau\right)}{\left(x \cdot \pi\right) \cdot tau} \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-*.f32N/A

      \[\leadsto \color{blue}{\frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau} \cdot \frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)}} \]
    2. *-commutativeN/A

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)} \cdot \frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau}} \]
    3. lift-/.f32N/A

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot \mathsf{PI}\left(\right)\right)}{x \cdot \mathsf{PI}\left(\right)}} \cdot \frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau} \]
    4. div-invN/A

      \[\leadsto \color{blue}{\left(\sin \left(x \cdot \mathsf{PI}\left(\right)\right) \cdot \frac{1}{x \cdot \mathsf{PI}\left(\right)}\right)} \cdot \frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau} \]
    5. associate-*l*N/A

      \[\leadsto \color{blue}{\sin \left(x \cdot \mathsf{PI}\left(\right)\right) \cdot \left(\frac{1}{x \cdot \mathsf{PI}\left(\right)} \cdot \frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau}\right)} \]
    6. *-commutativeN/A

      \[\leadsto \color{blue}{\left(\frac{1}{x \cdot \mathsf{PI}\left(\right)} \cdot \frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau}\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)} \]
    7. lower-*.f32N/A

      \[\leadsto \color{blue}{\left(\frac{1}{x \cdot \mathsf{PI}\left(\right)} \cdot \frac{\sin \left(\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}{\left(x \cdot \mathsf{PI}\left(\right)\right) \cdot tau}\right) \cdot \sin \left(x \cdot \mathsf{PI}\left(\right)\right)} \]
  4. Applied rewrites97.0%

    \[\leadsto \color{blue}{\frac{\sin \left(\pi \cdot \left(x \cdot tau\right)\right)}{x \cdot \left(\pi \cdot \left(\pi \cdot \left(x \cdot tau\right)\right)\right)} \cdot \sin \left(x \cdot \pi\right)} \]
  5. Applied rewrites97.3%

    \[\leadsto \color{blue}{\frac{\sin \left(x \cdot \pi\right) \cdot \sin \left(x \cdot \left(tau \cdot \pi\right)\right)}{x \cdot \left(tau \cdot \pi\right)} \cdot \frac{1}{x \cdot \pi}} \]
  6. Taylor expanded in x around 0

    \[\leadsto \color{blue}{\left(x \cdot \mathsf{PI}\left(\right)\right)} \cdot \frac{1}{x \cdot \mathsf{PI}\left(\right)} \]
  7. Step-by-step derivation
    1. lower-*.f32N/A

      \[\leadsto \color{blue}{\left(x \cdot \mathsf{PI}\left(\right)\right)} \cdot \frac{1}{x \cdot \mathsf{PI}\left(\right)} \]
    2. lower-PI.f3261.6

      \[\leadsto \left(x \cdot \color{blue}{\pi}\right) \cdot \frac{1}{x \cdot \pi} \]
  8. Applied rewrites61.6%

    \[\leadsto \color{blue}{\left(x \cdot \pi\right)} \cdot \frac{1}{x \cdot \pi} \]
  9. Final simplification61.6%

    \[\leadsto \frac{1}{x \cdot \pi} \cdot \left(x \cdot \pi\right) \]
  10. Add Preprocessing

Alternative 12: 62.8% accurate, 258.0× speedup?

\[\begin{array}{l} \\ 1 \end{array} \]
(FPCore (x tau) :precision binary32 1.0)
float code(float x, float tau) {
	return 1.0f;
}
real(4) function code(x, tau)
    real(4), intent (in) :: x
    real(4), intent (in) :: tau
    code = 1.0e0
end function
function code(x, tau)
	return Float32(1.0)
end
function tmp = code(x, tau)
	tmp = single(1.0);
end
\begin{array}{l}

\\
1
\end{array}
Derivation
  1. Initial program 97.6%

    \[\frac{\sin \left(\left(x \cdot \pi\right) \cdot tau\right)}{\left(x \cdot \pi\right) \cdot tau} \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi} \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0

    \[\leadsto \color{blue}{1} \]
  4. Step-by-step derivation
    1. Applied rewrites61.6%

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

    Reproduce

    ?
    herbie shell --seed 2024233 
    (FPCore (x tau)
      :name "Lanczos kernel"
      :precision binary32
      :pre (and (and (<= 1e-5 x) (<= x 1.0)) (and (<= 1.0 tau) (<= tau 5.0)))
      (* (/ (sin (* (* x PI) tau)) (* (* x PI) tau)) (/ (sin (* x PI)) (* x PI))))