
(FPCore (cosTheta alpha)
:precision binary32
(let* ((t_0 (- (* alpha alpha) 1.0)))
(/
t_0
(*
(* PI (log (* alpha alpha)))
(+ 1.0 (* (* t_0 cosTheta) cosTheta))))))float code(float cosTheta, float alpha) {
float t_0 = (alpha * alpha) - 1.0f;
return t_0 / ((((float) M_PI) * logf((alpha * alpha))) * (1.0f + ((t_0 * cosTheta) * cosTheta)));
}
function code(cosTheta, alpha) t_0 = Float32(Float32(alpha * alpha) - Float32(1.0)) return Float32(t_0 / Float32(Float32(Float32(pi) * log(Float32(alpha * alpha))) * Float32(Float32(1.0) + Float32(Float32(t_0 * cosTheta) * cosTheta)))) end
function tmp = code(cosTheta, alpha) t_0 = (alpha * alpha) - single(1.0); tmp = t_0 / ((single(pi) * log((alpha * alpha))) * (single(1.0) + ((t_0 * cosTheta) * cosTheta))); end
\begin{array}{l}
t_0 := \alpha \cdot \alpha - 1\\
\frac{t\_0}{\left(\pi \cdot \log \left(\alpha \cdot \alpha\right)\right) \cdot \left(1 + \left(t\_0 \cdot cosTheta\right) \cdot cosTheta\right)}
\end{array}
Herbie found 12 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (cosTheta alpha)
:precision binary32
(let* ((t_0 (- (* alpha alpha) 1.0)))
(/
t_0
(*
(* PI (log (* alpha alpha)))
(+ 1.0 (* (* t_0 cosTheta) cosTheta))))))float code(float cosTheta, float alpha) {
float t_0 = (alpha * alpha) - 1.0f;
return t_0 / ((((float) M_PI) * logf((alpha * alpha))) * (1.0f + ((t_0 * cosTheta) * cosTheta)));
}
function code(cosTheta, alpha) t_0 = Float32(Float32(alpha * alpha) - Float32(1.0)) return Float32(t_0 / Float32(Float32(Float32(pi) * log(Float32(alpha * alpha))) * Float32(Float32(1.0) + Float32(Float32(t_0 * cosTheta) * cosTheta)))) end
function tmp = code(cosTheta, alpha) t_0 = (alpha * alpha) - single(1.0); tmp = t_0 / ((single(pi) * log((alpha * alpha))) * (single(1.0) + ((t_0 * cosTheta) * cosTheta))); end
\begin{array}{l}
t_0 := \alpha \cdot \alpha - 1\\
\frac{t\_0}{\left(\pi \cdot \log \left(\alpha \cdot \alpha\right)\right) \cdot \left(1 + \left(t\_0 \cdot cosTheta\right) \cdot cosTheta\right)}
\end{array}
(FPCore (cosTheta alpha) :precision binary32 (/ (- (- (* alpha alpha) 0.5) 0.5) (* (* PI (log (* alpha alpha))) (+ 1.0 (* (* -1.0 cosTheta) cosTheta)))))
float code(float cosTheta, float alpha) {
return (((alpha * alpha) - 0.5f) - 0.5f) / ((((float) M_PI) * logf((alpha * alpha))) * (1.0f + ((-1.0f * cosTheta) * cosTheta)));
}
function code(cosTheta, alpha) return Float32(Float32(Float32(Float32(alpha * alpha) - Float32(0.5)) - Float32(0.5)) / Float32(Float32(Float32(pi) * log(Float32(alpha * alpha))) * Float32(Float32(1.0) + Float32(Float32(Float32(-1.0) * cosTheta) * cosTheta)))) end
function tmp = code(cosTheta, alpha) tmp = (((alpha * alpha) - single(0.5)) - single(0.5)) / ((single(pi) * log((alpha * alpha))) * (single(1.0) + ((single(-1.0) * cosTheta) * cosTheta))); end
\frac{\left(\alpha \cdot \alpha - 0.5\right) - 0.5}{\left(\pi \cdot \log \left(\alpha \cdot \alpha\right)\right) \cdot \left(1 + \left(-1 \cdot cosTheta\right) \cdot cosTheta\right)}
Initial program 98.5%
Taylor expanded in alpha around 0
lower-*.f3297.6%
Applied rewrites97.6%
lift--.f32N/A
lift-*.f32N/A
lift-*.f32N/A
metadata-evalN/A
associate--r+N/A
lower--.f32N/A
lower--.f3297.6%
Applied rewrites97.6%
(FPCore (cosTheta alpha) :precision binary32 (/ (- (* alpha alpha) 1.0) (* (* PI (log (* alpha alpha))) (+ 2.0 (fma (- cosTheta) cosTheta -1.0)))))
float code(float cosTheta, float alpha) {
return ((alpha * alpha) - 1.0f) / ((((float) M_PI) * logf((alpha * alpha))) * (2.0f + fmaf(-cosTheta, cosTheta, -1.0f)));
}
function code(cosTheta, alpha) return Float32(Float32(Float32(alpha * alpha) - Float32(1.0)) / Float32(Float32(Float32(pi) * log(Float32(alpha * alpha))) * Float32(Float32(2.0) + fma(Float32(-cosTheta), cosTheta, Float32(-1.0))))) end
\frac{\alpha \cdot \alpha - 1}{\left(\pi \cdot \log \left(\alpha \cdot \alpha\right)\right) \cdot \left(2 + \mathsf{fma}\left(-cosTheta, cosTheta, -1\right)\right)}
Initial program 98.5%
Taylor expanded in alpha around 0
lower-*.f3297.6%
Applied rewrites97.6%
+-lft-identityN/A
metadata-evalN/A
associate-+l-N/A
lower--.f32N/A
lower--.f3297.6%
lift-*.f32N/A
mul-1-negN/A
lower-neg.f3297.6%
Applied rewrites97.6%
lift-+.f32N/A
lift--.f32N/A
associate-+r-N/A
metadata-evalN/A
metadata-evalN/A
associate--l+N/A
metadata-evalN/A
associate-+r-N/A
lift--.f32N/A
lift--.f32N/A
lift--.f32N/A
associate--r-N/A
metadata-evalN/A
lift-*.f32N/A
*-commutativeN/A
Applied rewrites97.6%
(FPCore (cosTheta alpha) :precision binary32 (/ (- (* alpha alpha) 1.0) (* (* PI (log (* alpha alpha))) (+ 1.0 (* (* -1.0 cosTheta) cosTheta)))))
float code(float cosTheta, float alpha) {
return ((alpha * alpha) - 1.0f) / ((((float) M_PI) * logf((alpha * alpha))) * (1.0f + ((-1.0f * cosTheta) * cosTheta)));
}
function code(cosTheta, alpha) return Float32(Float32(Float32(alpha * alpha) - Float32(1.0)) / Float32(Float32(Float32(pi) * log(Float32(alpha * alpha))) * Float32(Float32(1.0) + Float32(Float32(Float32(-1.0) * cosTheta) * cosTheta)))) end
function tmp = code(cosTheta, alpha) tmp = ((alpha * alpha) - single(1.0)) / ((single(pi) * log((alpha * alpha))) * (single(1.0) + ((single(-1.0) * cosTheta) * cosTheta))); end
\frac{\alpha \cdot \alpha - 1}{\left(\pi \cdot \log \left(\alpha \cdot \alpha\right)\right) \cdot \left(1 + \left(-1 \cdot cosTheta\right) \cdot cosTheta\right)}
Initial program 98.5%
Taylor expanded in alpha around 0
lower-*.f3297.6%
Applied rewrites97.6%
(FPCore (cosTheta alpha) :precision binary32 (/ (- (* alpha alpha) 1.0) (* (* PI (log (* alpha alpha))) (fma (- cosTheta) cosTheta 1.0))))
float code(float cosTheta, float alpha) {
return ((alpha * alpha) - 1.0f) / ((((float) M_PI) * logf((alpha * alpha))) * fmaf(-cosTheta, cosTheta, 1.0f));
}
function code(cosTheta, alpha) return Float32(Float32(Float32(alpha * alpha) - Float32(1.0)) / Float32(Float32(Float32(pi) * log(Float32(alpha * alpha))) * fma(Float32(-cosTheta), cosTheta, Float32(1.0)))) end
\frac{\alpha \cdot \alpha - 1}{\left(\pi \cdot \log \left(\alpha \cdot \alpha\right)\right) \cdot \mathsf{fma}\left(-cosTheta, cosTheta, 1\right)}
Initial program 98.5%
Taylor expanded in alpha around 0
lower-*.f3297.6%
Applied rewrites97.6%
lift-+.f32N/A
+-commutativeN/A
lift-*.f32N/A
lower-fma.f3297.6%
lift-*.f32N/A
mul-1-negN/A
lower-neg.f3297.6%
Applied rewrites97.6%
(FPCore (cosTheta alpha) :precision binary32 (/ (- (- (* alpha alpha) 0.5) 0.5) (* (* PI (log (* alpha alpha))) 1.0)))
float code(float cosTheta, float alpha) {
return (((alpha * alpha) - 0.5f) - 0.5f) / ((((float) M_PI) * logf((alpha * alpha))) * 1.0f);
}
function code(cosTheta, alpha) return Float32(Float32(Float32(Float32(alpha * alpha) - Float32(0.5)) - Float32(0.5)) / Float32(Float32(Float32(pi) * log(Float32(alpha * alpha))) * Float32(1.0))) end
function tmp = code(cosTheta, alpha) tmp = (((alpha * alpha) - single(0.5)) - single(0.5)) / ((single(pi) * log((alpha * alpha))) * single(1.0)); end
\frac{\left(\alpha \cdot \alpha - 0.5\right) - 0.5}{\left(\pi \cdot \log \left(\alpha \cdot \alpha\right)\right) \cdot 1}
Initial program 98.5%
Taylor expanded in cosTheta around 0
Applied rewrites95.6%
lift--.f32N/A
lift-*.f32N/A
lift-*.f32N/A
metadata-evalN/A
associate--r+N/A
lower--.f32N/A
lower--.f3295.5%
Applied rewrites95.5%
(FPCore (cosTheta alpha) :precision binary32 (/ (- (* alpha alpha) 1.0) (* (* PI (log (* alpha alpha))) 1.0)))
float code(float cosTheta, float alpha) {
return ((alpha * alpha) - 1.0f) / ((((float) M_PI) * logf((alpha * alpha))) * 1.0f);
}
function code(cosTheta, alpha) return Float32(Float32(Float32(alpha * alpha) - Float32(1.0)) / Float32(Float32(Float32(pi) * log(Float32(alpha * alpha))) * Float32(1.0))) end
function tmp = code(cosTheta, alpha) tmp = ((alpha * alpha) - single(1.0)) / ((single(pi) * log((alpha * alpha))) * single(1.0)); end
\frac{\alpha \cdot \alpha - 1}{\left(\pi \cdot \log \left(\alpha \cdot \alpha\right)\right) \cdot 1}
Initial program 98.5%
Taylor expanded in cosTheta around 0
Applied rewrites95.6%
(FPCore (cosTheta alpha) :precision binary32 (/ (fma alpha alpha -1.0) (* (* PI (log (* alpha alpha))) 1.0)))
float code(float cosTheta, float alpha) {
return fmaf(alpha, alpha, -1.0f) / ((((float) M_PI) * logf((alpha * alpha))) * 1.0f);
}
function code(cosTheta, alpha) return Float32(fma(alpha, alpha, Float32(-1.0)) / Float32(Float32(Float32(pi) * log(Float32(alpha * alpha))) * Float32(1.0))) end
\frac{\mathsf{fma}\left(\alpha, \alpha, -1\right)}{\left(\pi \cdot \log \left(\alpha \cdot \alpha\right)\right) \cdot 1}
Initial program 98.5%
Taylor expanded in cosTheta around 0
Applied rewrites95.6%
--rgt-identityN/A
lift--.f32N/A
lift--.f32N/A
metadata-evalN/A
associate--r-N/A
lower-+.f32N/A
lower--.f3294.6%
lift--.f32N/A
sub-flipN/A
lift-*.f32N/A
metadata-evalN/A
lower-fma.f3294.6%
Applied rewrites94.6%
lift-+.f32N/A
lift--.f32N/A
lift-fma.f32N/A
difference-of-sqr--1N/A
difference-of-sqr-1N/A
lift-*.f32N/A
lift--.f32N/A
associate-+l-N/A
metadata-evalN/A
--rgt-identity95.6%
lift--.f32N/A
lift-*.f32N/A
difference-of-sqr-1N/A
difference-of-sqr--1N/A
lift-fma.f3295.5%
Applied rewrites95.5%
(FPCore (cosTheta alpha) :precision binary32 (/ -1.0 (* (* PI (log (* alpha alpha))) 1.0)))
float code(float cosTheta, float alpha) {
return -1.0f / ((((float) M_PI) * logf((alpha * alpha))) * 1.0f);
}
function code(cosTheta, alpha) return Float32(Float32(-1.0) / Float32(Float32(Float32(pi) * log(Float32(alpha * alpha))) * Float32(1.0))) end
function tmp = code(cosTheta, alpha) tmp = single(-1.0) / ((single(pi) * log((alpha * alpha))) * single(1.0)); end
\frac{-1}{\left(\pi \cdot \log \left(\alpha \cdot \alpha\right)\right) \cdot 1}
Initial program 98.5%
Taylor expanded in cosTheta around 0
Applied rewrites95.6%
Taylor expanded in alpha around 0
Applied rewrites66.0%
(FPCore (cosTheta alpha) :precision binary32 (/ -1.0 (* (* PI (- (- -0.5 (fma alpha alpha -0.5)))) 1.0)))
float code(float cosTheta, float alpha) {
return -1.0f / ((((float) M_PI) * -(-0.5f - fmaf(alpha, alpha, -0.5f))) * 1.0f);
}
function code(cosTheta, alpha) return Float32(Float32(-1.0) / Float32(Float32(Float32(pi) * Float32(-Float32(Float32(-0.5) - fma(alpha, alpha, Float32(-0.5))))) * Float32(1.0))) end
\frac{-1}{\left(\pi \cdot \left(-\left(-0.5 - \mathsf{fma}\left(\alpha, \alpha, -0.5\right)\right)\right)\right) \cdot 1}
Initial program 98.5%
Taylor expanded in cosTheta around 0
Applied rewrites95.6%
Taylor expanded in alpha around 0
Applied rewrites66.0%
lift-log.f32N/A
lift-*.f32N/A
pow2N/A
log-powN/A
*-commutativeN/A
lower-*.f32N/A
lower-log.f32N/A
*-rgt-identityN/A
metadata-evalN/A
mul-fabsN/A
lower-fabs.f32N/A
*-rgt-identity66.0%
Applied rewrites66.0%
lift-*.f32N/A
*-commutativeN/A
count-2-revN/A
flip-+N/A
+-inversesN/A
+-inversesN/A
lower-/.f32-0.0%
lower-/.f32N/A
+-inversesN/A
+-inversesN/A
flip-+N/A
distribute-lft-outN/A
metadata-evalN/A
*-rgt-identity3.0%
+-rgt-identityN/A
metadata-evalN/A
associate--l+N/A
lift-*.f32N/A
lift-fma.f32N/A
sub-negate-revN/A
lower-neg.f32N/A
lower--.f323.1%
Applied rewrites3.1%
(FPCore (cosTheta alpha) :precision binary32 (/ (fma alpha alpha -1.0) (* (* 1.0 PI) (* alpha alpha))))
float code(float cosTheta, float alpha) {
return fmaf(alpha, alpha, -1.0f) / ((1.0f * ((float) M_PI)) * (alpha * alpha));
}
function code(cosTheta, alpha) return Float32(fma(alpha, alpha, Float32(-1.0)) / Float32(Float32(Float32(1.0) * Float32(pi)) * Float32(alpha * alpha))) end
\frac{\mathsf{fma}\left(\alpha, \alpha, -1\right)}{\left(1 \cdot \pi\right) \cdot \left(\alpha \cdot \alpha\right)}
Initial program 98.5%
Taylor expanded in cosTheta around 0
Applied rewrites95.6%
--rgt-identityN/A
lift--.f32N/A
lift--.f32N/A
metadata-evalN/A
associate--r-N/A
lower-+.f32N/A
lower--.f3294.6%
lift--.f32N/A
sub-flipN/A
lift-*.f32N/A
metadata-evalN/A
lower-fma.f3294.6%
Applied rewrites94.6%
lift--.f32N/A
lift-fma.f32N/A
difference-of-sqr--1N/A
difference-of-sqr-1N/A
lift-*.f32N/A
associate--l-N/A
metadata-evalN/A
metadata-evalN/A
metadata-evalN/A
*-rgt-identityN/A
*-rgt-identityN/A
lower-*.f32N/A
metadata-evalN/A
metadata-evalN/A
metadata-evalN/A
difference-of-squaresN/A
lower-*.f32N/A
lower-+.f32N/A
*-rgt-identityN/A
lower--.f32N/A
*-rgt-identity93.3%
Applied rewrites93.3%
lift-+.f32N/A
lift-*.f32N/A
lift-+.f32N/A
lift--.f32N/A
difference-of-squares-revN/A
lift-*.f32N/A
associate-+l-N/A
lift-*.f32N/A
metadata-evalN/A
metadata-evalN/A
difference-of-sqr-1N/A
difference-of-sqr--1-revN/A
lower-fma.f3295.5%
lift-*.f32N/A
*-commutativeN/A
lift-*.f32N/A
associate-*r*N/A
lower-*.f32N/A
Applied rewrites3.0%
(FPCore (cosTheta alpha) :precision binary32 (/ -1.0 (* (* (* alpha alpha) PI) 1.0)))
float code(float cosTheta, float alpha) {
return -1.0f / (((alpha * alpha) * ((float) M_PI)) * 1.0f);
}
function code(cosTheta, alpha) return Float32(Float32(-1.0) / Float32(Float32(Float32(alpha * alpha) * Float32(pi)) * Float32(1.0))) end
function tmp = code(cosTheta, alpha) tmp = single(-1.0) / (((alpha * alpha) * single(pi)) * single(1.0)); end
\frac{-1}{\left(\left(\alpha \cdot \alpha\right) \cdot \pi\right) \cdot 1}
Initial program 98.5%
Taylor expanded in cosTheta around 0
Applied rewrites95.6%
Taylor expanded in alpha around 0
Applied rewrites66.0%
lift-log.f32N/A
lift-*.f32N/A
pow2N/A
log-powN/A
*-commutativeN/A
lower-*.f32N/A
lower-log.f32N/A
*-rgt-identityN/A
metadata-evalN/A
mul-fabsN/A
lower-fabs.f32N/A
*-rgt-identity66.0%
Applied rewrites66.0%
lift-*.f32N/A
lift-*.f32N/A
associate-*r*N/A
*-commutativeN/A
*-commutativeN/A
associate-*l*N/A
lower-log.f32N/A
lift-fabs.f32N/A
log-powN/A
pow2N/A
lift-*.f32N/A
lift-log.f32N/A
lower-*.f3266.0%
Applied rewrites3.0%
herbie shell --seed 2025322
(FPCore (cosTheta alpha)
:name "GTR1 distribution"
:precision binary32
:pre (and (and (<= 0.0 cosTheta) (<= cosTheta 1.0)) (and (<= 0.0001 alpha) (<= alpha 1.0)))
(/ (- (* alpha alpha) 1.0) (* (* PI (log (* alpha alpha))) (+ 1.0 (* (* (- (* alpha alpha) 1.0) cosTheta) cosTheta)))))