
(FPCore (x y z a) :precision binary64 (+ x (- (tan (+ y z)) (tan a))))
double code(double x, double y, double z, double a) {
return x + (tan((y + z)) - tan(a));
}
real(8) function code(x, y, z, a)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8), intent (in) :: a
code = x + (tan((y + z)) - tan(a))
end function
public static double code(double x, double y, double z, double a) {
return x + (Math.tan((y + z)) - Math.tan(a));
}
def code(x, y, z, a): return x + (math.tan((y + z)) - math.tan(a))
function code(x, y, z, a) return Float64(x + Float64(tan(Float64(y + z)) - tan(a))) end
function tmp = code(x, y, z, a) tmp = x + (tan((y + z)) - tan(a)); end
code[x_, y_, z_, a_] := N[(x + N[(N[Tan[N[(y + z), $MachinePrecision]], $MachinePrecision] - N[Tan[a], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x + \left(\tan \left(y + z\right) - \tan a\right)
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 13 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x y z a) :precision binary64 (+ x (- (tan (+ y z)) (tan a))))
double code(double x, double y, double z, double a) {
return x + (tan((y + z)) - tan(a));
}
real(8) function code(x, y, z, a)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8), intent (in) :: a
code = x + (tan((y + z)) - tan(a))
end function
public static double code(double x, double y, double z, double a) {
return x + (Math.tan((y + z)) - Math.tan(a));
}
def code(x, y, z, a): return x + (math.tan((y + z)) - math.tan(a))
function code(x, y, z, a) return Float64(x + Float64(tan(Float64(y + z)) - tan(a))) end
function tmp = code(x, y, z, a) tmp = x + (tan((y + z)) - tan(a)); end
code[x_, y_, z_, a_] := N[(x + N[(N[Tan[N[(y + z), $MachinePrecision]], $MachinePrecision] - N[Tan[a], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x + \left(\tan \left(y + z\right) - \tan a\right)
\end{array}
(FPCore (x y z a) :precision binary64 (+ x (fma (/ 1.0 (- 1.0 (* (tan y) (tan z)))) (+ (tan y) (tan z)) (- (tan a)))))
double code(double x, double y, double z, double a) {
return x + fma((1.0 / (1.0 - (tan(y) * tan(z)))), (tan(y) + tan(z)), -tan(a));
}
function code(x, y, z, a) return Float64(x + fma(Float64(1.0 / Float64(1.0 - Float64(tan(y) * tan(z)))), Float64(tan(y) + tan(z)), Float64(-tan(a)))) end
code[x_, y_, z_, a_] := N[(x + N[(N[(1.0 / N[(1.0 - N[(N[Tan[y], $MachinePrecision] * N[Tan[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(N[Tan[y], $MachinePrecision] + N[Tan[z], $MachinePrecision]), $MachinePrecision] + (-N[Tan[a], $MachinePrecision])), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x + \mathsf{fma}\left(\frac{1}{1 - \tan y \cdot \tan z}, \tan y + \tan z, -\tan a\right)
\end{array}
Initial program 80.5%
lift--.f64N/A
sub-negN/A
lift-tan.f64N/A
lift-+.f64N/A
tan-sumN/A
clear-numN/A
associate-/r/N/A
lower-fma.f64N/A
lower-/.f64N/A
lower--.f64N/A
lower-*.f64N/A
lower-tan.f64N/A
lower-tan.f64N/A
lower-+.f64N/A
lower-tan.f64N/A
lower-tan.f64N/A
lower-neg.f6499.8
Applied rewrites99.8%
(FPCore (x y z a)
:precision binary64
(let* ((t_0 (+ (tan y) (tan z))) (t_1 (+ x (fma 1.0 t_0 (- (tan a))))))
(if (<= (tan a) -0.02)
t_1
(if (<= (tan a) 5e-46)
(fma
(/ 1.0 (- 1.0 (* (tan y) (tan z))))
t_0
(- x (fma a (* 0.3333333333333333 (* a a)) a)))
t_1))))
double code(double x, double y, double z, double a) {
double t_0 = tan(y) + tan(z);
double t_1 = x + fma(1.0, t_0, -tan(a));
double tmp;
if (tan(a) <= -0.02) {
tmp = t_1;
} else if (tan(a) <= 5e-46) {
tmp = fma((1.0 / (1.0 - (tan(y) * tan(z)))), t_0, (x - fma(a, (0.3333333333333333 * (a * a)), a)));
} else {
tmp = t_1;
}
return tmp;
}
function code(x, y, z, a) t_0 = Float64(tan(y) + tan(z)) t_1 = Float64(x + fma(1.0, t_0, Float64(-tan(a)))) tmp = 0.0 if (tan(a) <= -0.02) tmp = t_1; elseif (tan(a) <= 5e-46) tmp = fma(Float64(1.0 / Float64(1.0 - Float64(tan(y) * tan(z)))), t_0, Float64(x - fma(a, Float64(0.3333333333333333 * Float64(a * a)), a))); else tmp = t_1; end return tmp end
code[x_, y_, z_, a_] := Block[{t$95$0 = N[(N[Tan[y], $MachinePrecision] + N[Tan[z], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(x + N[(1.0 * t$95$0 + (-N[Tan[a], $MachinePrecision])), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[Tan[a], $MachinePrecision], -0.02], t$95$1, If[LessEqual[N[Tan[a], $MachinePrecision], 5e-46], N[(N[(1.0 / N[(1.0 - N[(N[Tan[y], $MachinePrecision] * N[Tan[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * t$95$0 + N[(x - N[(a * N[(0.3333333333333333 * N[(a * a), $MachinePrecision]), $MachinePrecision] + a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], t$95$1]]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \tan y + \tan z\\
t_1 := x + \mathsf{fma}\left(1, t\_0, -\tan a\right)\\
\mathbf{if}\;\tan a \leq -0.02:\\
\;\;\;\;t\_1\\
\mathbf{elif}\;\tan a \leq 5 \cdot 10^{-46}:\\
\;\;\;\;\mathsf{fma}\left(\frac{1}{1 - \tan y \cdot \tan z}, t\_0, x - \mathsf{fma}\left(a, 0.3333333333333333 \cdot \left(a \cdot a\right), a\right)\right)\\
\mathbf{else}:\\
\;\;\;\;t\_1\\
\end{array}
\end{array}
if (tan.f64 a) < -0.0200000000000000004 or 4.99999999999999992e-46 < (tan.f64 a) Initial program 80.3%
lift--.f64N/A
sub-negN/A
lift-tan.f64N/A
lift-+.f64N/A
tan-sumN/A
clear-numN/A
associate-/r/N/A
lower-fma.f64N/A
lower-/.f64N/A
lower--.f64N/A
lower-*.f64N/A
lower-tan.f64N/A
lower-tan.f64N/A
lower-+.f64N/A
lower-tan.f64N/A
lower-tan.f64N/A
lower-neg.f6499.6
Applied rewrites99.6%
Taylor expanded in y around 0
Applied rewrites80.7%
if -0.0200000000000000004 < (tan.f64 a) < 4.99999999999999992e-46Initial program 79.4%
Taylor expanded in a around 0
+-commutativeN/A
distribute-lft-inN/A
associate-*r*N/A
*-commutativeN/A
*-rgt-identityN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f64N/A
lower-*.f6478.9
Applied rewrites78.9%
lift-+.f64N/A
+-commutativeN/A
lift--.f64N/A
sub-negN/A
associate-+l+N/A
Applied rewrites99.1%
Final simplification89.2%
herbie shell --seed 2024223
(FPCore (x y z a)
:name "tan-example (used to crash)"
:precision binary64
:pre (and (and (and (or (== x 0.0) (and (<= 0.5884142 x) (<= x 505.5909))) (or (and (<= -1.796658e+308 y) (<= y -9.425585e-310)) (and (<= 1.284938e-309 y) (<= y 1.751224e+308)))) (or (and (<= -1.776707e+308 z) (<= z -8.599796e-310)) (and (<= 3.293145e-311 z) (<= z 1.725154e+308)))) (or (and (<= -1.796658e+308 a) (<= a -9.425585e-310)) (and (<= 1.284938e-309 a) (<= a 1.751224e+308))))
(+ x (- (tan (+ y z)) (tan a))))