
(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:
Herbie found 15 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(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}
(FPCore (x tau) :precision binary32 (let* ((t_1 (* tau (* x PI)))) (* (/ (sin t_1) t_1) (/ (sin (* x PI)) (* x PI)))))
float code(float x, float tau) {
float t_1 = tau * (x * ((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(tau * Float32(x * 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 = tau * (x * single(pi)); tmp = (sin(t_1) / t_1) * (sin((x * single(pi))) / (x * single(pi))); end
\begin{array}{l}
\\
\begin{array}{l}
t_1 := tau \cdot \left(x \cdot \pi\right)\\
\frac{\sin t_1}{t_1} \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi}
\end{array}
\end{array}
Initial program 97.9%
Final simplification97.9%
(FPCore (x tau) :precision binary32 (* (sin (* tau (* x PI))) (/ (sin (* x PI)) (* tau (pow (* x PI) 2.0)))))
float code(float x, float tau) {
return sinf((tau * (x * ((float) M_PI)))) * (sinf((x * ((float) M_PI))) / (tau * powf((x * ((float) M_PI)), 2.0f)));
}
function code(x, tau) return Float32(sin(Float32(tau * Float32(x * Float32(pi)))) * Float32(sin(Float32(x * Float32(pi))) / Float32(tau * (Float32(x * Float32(pi)) ^ Float32(2.0))))) end
function tmp = code(x, tau) tmp = sin((tau * (x * single(pi)))) * (sin((x * single(pi))) / (tau * ((x * single(pi)) ^ single(2.0)))); end
\begin{array}{l}
\\
\sin \left(tau \cdot \left(x \cdot \pi\right)\right) \cdot \frac{\sin \left(x \cdot \pi\right)}{tau \cdot {\left(x \cdot \pi\right)}^{2}}
\end{array}
Initial program 97.9%
associate-*r/97.9%
associate-*l/97.7%
associate-/l/97.8%
associate-*r/97.8%
associate-*l*97.1%
associate-*r*97.1%
associate-/r*97.0%
associate-/l/97.1%
swap-sqr96.9%
associate-*r*96.8%
Simplified96.8%
Taylor expanded in x around -inf 96.7%
Taylor expanded in x around inf 96.8%
associate-/r*96.8%
unpow296.8%
unpow296.8%
swap-sqr97.4%
unpow297.4%
associate-/r*97.4%
Simplified97.4%
Final simplification97.4%
(FPCore (x tau)
:precision binary32
(let* ((t_1 (* x (* PI tau))))
(*
(+ 1.0 (* -0.16666666666666666 (* (pow PI 2.0) (* x x))))
(/ (sin t_1) t_1))))
float code(float x, float tau) {
float t_1 = x * (((float) M_PI) * tau);
return (1.0f + (-0.16666666666666666f * (powf(((float) M_PI), 2.0f) * (x * x)))) * (sinf(t_1) / t_1);
}
function code(x, tau) t_1 = Float32(x * Float32(Float32(pi) * tau)) return Float32(Float32(Float32(1.0) + Float32(Float32(-0.16666666666666666) * Float32((Float32(pi) ^ Float32(2.0)) * Float32(x * x)))) * Float32(sin(t_1) / t_1)) end
function tmp = code(x, tau) t_1 = x * (single(pi) * tau); tmp = (single(1.0) + (single(-0.16666666666666666) * ((single(pi) ^ single(2.0)) * (x * x)))) * (sin(t_1) / t_1); end
\begin{array}{l}
\\
\begin{array}{l}
t_1 := x \cdot \left(\pi \cdot tau\right)\\
\left(1 + -0.16666666666666666 \cdot \left({\pi}^{2} \cdot \left(x \cdot x\right)\right)\right) \cdot \frac{\sin t_1}{t_1}
\end{array}
\end{array}
Initial program 97.9%
Taylor expanded in x around 0 86.7%
*-commutative86.7%
unpow286.7%
Simplified86.7%
associate-*r*86.1%
*-un-lft-identity86.1%
associate-*r*86.7%
*-commutative86.7%
times-frac86.5%
associate-*r*86.1%
*-commutative86.1%
associate-*l*86.0%
Applied egg-rr86.0%
Taylor expanded in tau around inf 86.7%
*-commutative86.7%
associate-*r*86.1%
*-commutative86.1%
*-commutative86.1%
associate-*r*86.7%
Simplified86.7%
Final simplification86.7%
(FPCore (x tau)
:precision binary32
(let* ((t_1 (* PI (* x tau))))
(*
(/ (sin t_1) t_1)
(+ 1.0 (* -0.16666666666666666 (* (pow PI 2.0) (* x x)))))))
float code(float x, float tau) {
float t_1 = ((float) M_PI) * (x * tau);
return (sinf(t_1) / t_1) * (1.0f + (-0.16666666666666666f * (powf(((float) M_PI), 2.0f) * (x * x))));
}
function code(x, tau) t_1 = Float32(Float32(pi) * Float32(x * tau)) return Float32(Float32(sin(t_1) / t_1) * Float32(Float32(1.0) + Float32(Float32(-0.16666666666666666) * Float32((Float32(pi) ^ Float32(2.0)) * Float32(x * x))))) end
function tmp = code(x, tau) t_1 = single(pi) * (x * tau); tmp = (sin(t_1) / t_1) * (single(1.0) + (single(-0.16666666666666666) * ((single(pi) ^ single(2.0)) * (x * x)))); end
\begin{array}{l}
\\
\begin{array}{l}
t_1 := \pi \cdot \left(x \cdot tau\right)\\
\frac{\sin t_1}{t_1} \cdot \left(1 + -0.16666666666666666 \cdot \left({\pi}^{2} \cdot \left(x \cdot x\right)\right)\right)
\end{array}
\end{array}
Initial program 97.9%
Taylor expanded in x around 0 86.7%
*-commutative86.7%
unpow286.7%
Simplified86.7%
Taylor expanded in x around inf 86.7%
associate-*r*86.0%
*-commutative86.0%
*-commutative86.0%
*-commutative86.0%
*-commutative86.0%
associate-*r*86.7%
*-commutative86.7%
Simplified86.7%
Final simplification86.7%
(FPCore (x tau) :precision binary32 (let* ((t_1 (* tau (* x PI)))) (* (/ (sin t_1) t_1) (+ 1.0 (* (pow (* x PI) 2.0) -0.16666666666666666)))))
float code(float x, float tau) {
float t_1 = tau * (x * ((float) M_PI));
return (sinf(t_1) / t_1) * (1.0f + (powf((x * ((float) M_PI)), 2.0f) * -0.16666666666666666f));
}
function code(x, tau) t_1 = Float32(tau * Float32(x * Float32(pi))) return Float32(Float32(sin(t_1) / t_1) * Float32(Float32(1.0) + Float32((Float32(x * Float32(pi)) ^ Float32(2.0)) * Float32(-0.16666666666666666)))) end
function tmp = code(x, tau) t_1 = tau * (x * single(pi)); tmp = (sin(t_1) / t_1) * (single(1.0) + (((x * single(pi)) ^ single(2.0)) * single(-0.16666666666666666))); end
\begin{array}{l}
\\
\begin{array}{l}
t_1 := tau \cdot \left(x \cdot \pi\right)\\
\frac{\sin t_1}{t_1} \cdot \left(1 + {\left(x \cdot \pi\right)}^{2} \cdot -0.16666666666666666\right)
\end{array}
\end{array}
Initial program 97.9%
Taylor expanded in x around 0 86.7%
*-commutative86.7%
unpow286.7%
Simplified86.7%
pow286.7%
pow-prod-down86.7%
Applied egg-rr86.7%
Final simplification86.7%
(FPCore (x tau) :precision binary32 (let* ((t_1 (* tau (* x PI)))) (* (sin t_1) (+ (* -0.16666666666666666 (/ (* x PI) tau)) (/ 1.0 t_1)))))
float code(float x, float tau) {
float t_1 = tau * (x * ((float) M_PI));
return sinf(t_1) * ((-0.16666666666666666f * ((x * ((float) M_PI)) / tau)) + (1.0f / t_1));
}
function code(x, tau) t_1 = Float32(tau * Float32(x * Float32(pi))) return Float32(sin(t_1) * Float32(Float32(Float32(-0.16666666666666666) * Float32(Float32(x * Float32(pi)) / tau)) + Float32(Float32(1.0) / t_1))) end
function tmp = code(x, tau) t_1 = tau * (x * single(pi)); tmp = sin(t_1) * ((single(-0.16666666666666666) * ((x * single(pi)) / tau)) + (single(1.0) / t_1)); end
\begin{array}{l}
\\
\begin{array}{l}
t_1 := tau \cdot \left(x \cdot \pi\right)\\
\sin t_1 \cdot \left(-0.16666666666666666 \cdot \frac{x \cdot \pi}{tau} + \frac{1}{t_1}\right)
\end{array}
\end{array}
Initial program 97.9%
associate-*r/97.9%
associate-*l/97.7%
associate-/l/97.8%
associate-*r/97.8%
associate-*l*97.1%
associate-*r*97.1%
associate-/r*97.0%
associate-/l/97.1%
swap-sqr96.9%
associate-*r*96.8%
Simplified96.8%
Taylor expanded in x around -inf 96.7%
Taylor expanded in x around 0 86.5%
Final simplification86.5%
(FPCore (x tau) :precision binary32 (+ 1.0 (* (* x x) (* -0.16666666666666666 (+ (pow PI 2.0) (* (pow PI 2.0) (* tau tau)))))))
float code(float x, float tau) {
return 1.0f + ((x * x) * (-0.16666666666666666f * (powf(((float) M_PI), 2.0f) + (powf(((float) M_PI), 2.0f) * (tau * tau)))));
}
function code(x, tau) return Float32(Float32(1.0) + Float32(Float32(x * x) * Float32(Float32(-0.16666666666666666) * Float32((Float32(pi) ^ Float32(2.0)) + Float32((Float32(pi) ^ Float32(2.0)) * Float32(tau * tau)))))) end
function tmp = code(x, tau) tmp = single(1.0) + ((x * x) * (single(-0.16666666666666666) * ((single(pi) ^ single(2.0)) + ((single(pi) ^ single(2.0)) * (tau * tau))))); end
\begin{array}{l}
\\
1 + \left(x \cdot x\right) \cdot \left(-0.16666666666666666 \cdot \left({\pi}^{2} + {\pi}^{2} \cdot \left(tau \cdot tau\right)\right)\right)
\end{array}
Initial program 97.9%
*-commutative97.9%
times-frac97.8%
associate-*r/97.6%
associate-*r*97.2%
associate-/r*97.2%
associate-/l/97.2%
associate-*l*97.0%
swap-sqr96.8%
associate-*r*96.7%
Simplified96.7%
Taylor expanded in x around 0 80.4%
distribute-lft-out80.4%
*-commutative80.4%
unpow280.4%
unpow280.4%
Simplified80.4%
Final simplification80.4%
(FPCore (x tau) :precision binary32 (fma (* x x) (* (pow PI 2.0) (* -0.16666666666666666 (fma tau tau 1.0))) 1.0))
float code(float x, float tau) {
return fmaf((x * x), (powf(((float) M_PI), 2.0f) * (-0.16666666666666666f * fmaf(tau, tau, 1.0f))), 1.0f);
}
function code(x, tau) return fma(Float32(x * x), Float32((Float32(pi) ^ Float32(2.0)) * Float32(Float32(-0.16666666666666666) * fma(tau, tau, Float32(1.0)))), Float32(1.0)) end
\begin{array}{l}
\\
\mathsf{fma}\left(x \cdot x, {\pi}^{2} \cdot \left(-0.16666666666666666 \cdot \mathsf{fma}\left(tau, tau, 1\right)\right), 1\right)
\end{array}
Initial program 97.9%
associate-*r/97.9%
associate-*l/97.7%
associate-/l/97.8%
associate-*r/97.8%
associate-*l*97.1%
associate-*r*97.1%
associate-/r*97.0%
associate-/l/97.1%
swap-sqr96.9%
associate-*r*96.8%
Simplified96.8%
Taylor expanded in x around -inf 96.7%
Taylor expanded in x around 0 80.4%
+-commutative80.4%
*-commutative80.4%
fma-def80.4%
unpow280.4%
distribute-lft-out80.4%
*-lft-identity80.4%
distribute-rgt-out80.4%
unpow280.4%
Simplified80.4%
Taylor expanded in tau around 0 80.4%
+-commutative80.4%
unpow280.4%
*-commutative80.4%
associate-*l*80.4%
*-rgt-identity80.4%
distribute-lft-out80.4%
*-commutative80.4%
fma-udef80.4%
associate-*l*80.4%
Simplified80.4%
Final simplification80.4%
(FPCore (x tau) :precision binary32 (fma (* x x) (* -0.16666666666666666 (* (pow PI 2.0) (+ 1.0 (* tau tau)))) 1.0))
float code(float x, float tau) {
return fmaf((x * x), (-0.16666666666666666f * (powf(((float) M_PI), 2.0f) * (1.0f + (tau * tau)))), 1.0f);
}
function code(x, tau) return fma(Float32(x * x), Float32(Float32(-0.16666666666666666) * Float32((Float32(pi) ^ Float32(2.0)) * Float32(Float32(1.0) + Float32(tau * tau)))), Float32(1.0)) end
\begin{array}{l}
\\
\mathsf{fma}\left(x \cdot x, -0.16666666666666666 \cdot \left({\pi}^{2} \cdot \left(1 + tau \cdot tau\right)\right), 1\right)
\end{array}
Initial program 97.9%
associate-*r/97.9%
associate-*l/97.7%
associate-/l/97.8%
associate-*r/97.8%
associate-*l*97.1%
associate-*r*97.1%
associate-/r*97.0%
associate-/l/97.1%
swap-sqr96.9%
associate-*r*96.8%
Simplified96.8%
Taylor expanded in x around -inf 96.7%
Taylor expanded in x around 0 80.4%
+-commutative80.4%
*-commutative80.4%
fma-def80.4%
unpow280.4%
distribute-lft-out80.4%
*-lft-identity80.4%
distribute-rgt-out80.4%
unpow280.4%
Simplified80.4%
Final simplification80.4%
(FPCore (x tau) :precision binary32 (let* ((t_1 (* tau (* x PI)))) (* (sin t_1) (/ 1.0 t_1))))
float code(float x, float tau) {
float t_1 = tau * (x * ((float) M_PI));
return sinf(t_1) * (1.0f / t_1);
}
function code(x, tau) t_1 = Float32(tau * Float32(x * Float32(pi))) return Float32(sin(t_1) * Float32(Float32(1.0) / t_1)) end
function tmp = code(x, tau) t_1 = tau * (x * single(pi)); tmp = sin(t_1) * (single(1.0) / t_1); end
\begin{array}{l}
\\
\begin{array}{l}
t_1 := tau \cdot \left(x \cdot \pi\right)\\
\sin t_1 \cdot \frac{1}{t_1}
\end{array}
\end{array}
Initial program 97.9%
associate-*r/97.9%
associate-*l/97.7%
associate-/l/97.8%
associate-*r/97.8%
associate-*l*97.1%
associate-*r*97.1%
associate-/r*97.0%
associate-/l/97.1%
swap-sqr96.9%
associate-*r*96.8%
Simplified96.8%
Taylor expanded in x around -inf 96.7%
Taylor expanded in x around 0 72.1%
Final simplification72.1%
(FPCore (x tau) :precision binary32 (fma (* x x) (* -0.16666666666666666 (pow (* PI tau) 2.0)) 1.0))
float code(float x, float tau) {
return fmaf((x * x), (-0.16666666666666666f * powf((((float) M_PI) * tau), 2.0f)), 1.0f);
}
function code(x, tau) return fma(Float32(x * x), Float32(Float32(-0.16666666666666666) * (Float32(Float32(pi) * tau) ^ Float32(2.0))), Float32(1.0)) end
\begin{array}{l}
\\
\mathsf{fma}\left(x \cdot x, -0.16666666666666666 \cdot {\left(\pi \cdot tau\right)}^{2}, 1\right)
\end{array}
Initial program 97.9%
associate-*r/97.9%
associate-*l/97.7%
associate-/l/97.8%
associate-*r/97.8%
associate-*l*97.1%
associate-*r*97.1%
associate-/r*97.0%
associate-/l/97.1%
swap-sqr96.9%
associate-*r*96.8%
Simplified96.8%
Taylor expanded in x around -inf 96.7%
Taylor expanded in x around 0 80.4%
+-commutative80.4%
*-commutative80.4%
fma-def80.4%
unpow280.4%
distribute-lft-out80.4%
*-lft-identity80.4%
distribute-rgt-out80.4%
unpow280.4%
Simplified80.4%
Taylor expanded in tau around inf 71.1%
unpow271.1%
*-commutative71.1%
unpow271.1%
swap-sqr71.1%
unpow271.1%
Simplified71.1%
Final simplification71.1%
(FPCore (x tau) :precision binary32 (let* ((t_1 (* tau (* x PI)))) (/ (sin t_1) t_1)))
float code(float x, float tau) {
float t_1 = tau * (x * ((float) M_PI));
return sinf(t_1) / t_1;
}
function code(x, tau) t_1 = Float32(tau * Float32(x * Float32(pi))) return Float32(sin(t_1) / t_1) end
function tmp = code(x, tau) t_1 = tau * (x * single(pi)); tmp = sin(t_1) / t_1; end
\begin{array}{l}
\\
\begin{array}{l}
t_1 := tau \cdot \left(x \cdot \pi\right)\\
\frac{\sin t_1}{t_1}
\end{array}
\end{array}
Initial program 97.9%
clear-num97.8%
associate-/r/97.6%
*-commutative97.6%
*-commutative97.6%
Applied egg-rr97.6%
Taylor expanded in x around 0 72.2%
Final simplification72.2%
(FPCore (x tau) :precision binary32 (fma (* x x) (* -0.16666666666666666 (pow PI 2.0)) 1.0))
float code(float x, float tau) {
return fmaf((x * x), (-0.16666666666666666f * powf(((float) M_PI), 2.0f)), 1.0f);
}
function code(x, tau) return fma(Float32(x * x), Float32(Float32(-0.16666666666666666) * (Float32(pi) ^ Float32(2.0))), Float32(1.0)) end
\begin{array}{l}
\\
\mathsf{fma}\left(x \cdot x, -0.16666666666666666 \cdot {\pi}^{2}, 1\right)
\end{array}
Initial program 97.9%
associate-*r/97.9%
associate-*l/97.7%
associate-/l/97.8%
associate-*r/97.8%
associate-*l*97.1%
associate-*r*97.1%
associate-/r*97.0%
associate-/l/97.1%
swap-sqr96.9%
associate-*r*96.8%
Simplified96.8%
Taylor expanded in x around -inf 96.7%
Taylor expanded in x around 0 80.4%
+-commutative80.4%
*-commutative80.4%
fma-def80.4%
unpow280.4%
distribute-lft-out80.4%
*-lft-identity80.4%
distribute-rgt-out80.4%
unpow280.4%
Simplified80.4%
Taylor expanded in tau around 0 65.9%
Final simplification65.9%
(FPCore (x tau) :precision binary32 (/ (sin (* x PI)) (* x PI)))
float code(float x, float tau) {
return sinf((x * ((float) M_PI))) / (x * ((float) M_PI));
}
function code(x, tau) return Float32(sin(Float32(x * Float32(pi))) / Float32(x * Float32(pi))) end
function tmp = code(x, tau) tmp = sin((x * single(pi))) / (x * single(pi)); end
\begin{array}{l}
\\
\frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi}
\end{array}
Initial program 97.9%
*-commutative97.9%
times-frac97.8%
associate-*r/97.6%
associate-*r*97.2%
associate-/r*97.2%
associate-/l/97.2%
associate-*l*97.0%
swap-sqr96.8%
associate-*r*96.7%
Simplified96.7%
Taylor expanded in tau around 0 65.8%
*-commutative65.8%
Simplified65.8%
Final simplification65.8%
(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}
Initial program 97.9%
*-commutative97.9%
times-frac97.8%
associate-*r/97.6%
associate-*r*97.2%
associate-/r*97.2%
associate-/l/97.2%
associate-*l*97.0%
swap-sqr96.8%
associate-*r*96.7%
Simplified96.7%
Taylor expanded in x around 0 65.0%
Final simplification65.0%
herbie shell --seed 2023278
(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))))