bug500 (missed optimization)

Percentage Accurate: 69.6% → 99.5%
Time: 8.3s
Alternatives: 6
Speedup: 14.7×

Specification

?
\[-1000 < x \land x < 1000\]
\[\begin{array}{l} \\ \sin x - x \end{array} \]
(FPCore (x) :precision binary64 (- (sin x) x))
double code(double x) {
	return sin(x) - x;
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = sin(x) - x
end function
public static double code(double x) {
	return Math.sin(x) - x;
}
def code(x):
	return math.sin(x) - x
function code(x)
	return Float64(sin(x) - x)
end
function tmp = code(x)
	tmp = sin(x) - x;
end
code[x_] := N[(N[Sin[x], $MachinePrecision] - x), $MachinePrecision]
\begin{array}{l}

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

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 6 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: 69.6% accurate, 1.0× speedup?

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

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

Alternative 1: 99.5% accurate, 0.3× speedup?

\[\begin{array}{l} x\_m = \left|x\right| \\ x\_s = \mathsf{copysign}\left(1, x\right) \\ x\_s \cdot \begin{array}{l} \mathbf{if}\;\sin x\_m - x\_m \leq -0.05:\\ \;\;\;\;\frac{\left(0.5 + -0.5 \cdot \cos \left(x\_m \cdot 2\right)\right) - x\_m \cdot x\_m}{x\_m + \sin x\_m}\\ \mathbf{else}:\\ \;\;\;\;x\_m \cdot \frac{x\_m \cdot \left(x\_m \cdot 0.027777777777777776\right)}{-0.16666666666666666 + \left(x\_m \cdot x\_m\right) \cdot -0.008333333333333333}\\ \end{array} \end{array} \]
x\_m = (fabs.f64 x)
x\_s = (copysign.f64 #s(literal 1 binary64) x)
(FPCore (x_s x_m)
 :precision binary64
 (*
  x_s
  (if (<= (- (sin x_m) x_m) -0.05)
    (/ (- (+ 0.5 (* -0.5 (cos (* x_m 2.0)))) (* x_m x_m)) (+ x_m (sin x_m)))
    (*
     x_m
     (/
      (* x_m (* x_m 0.027777777777777776))
      (+ -0.16666666666666666 (* (* x_m x_m) -0.008333333333333333)))))))
x\_m = fabs(x);
x\_s = copysign(1.0, x);
double code(double x_s, double x_m) {
	double tmp;
	if ((sin(x_m) - x_m) <= -0.05) {
		tmp = ((0.5 + (-0.5 * cos((x_m * 2.0)))) - (x_m * x_m)) / (x_m + sin(x_m));
	} else {
		tmp = x_m * ((x_m * (x_m * 0.027777777777777776)) / (-0.16666666666666666 + ((x_m * x_m) * -0.008333333333333333)));
	}
	return x_s * tmp;
}
x\_m = abs(x)
x\_s = copysign(1.0d0, x)
real(8) function code(x_s, x_m)
    real(8), intent (in) :: x_s
    real(8), intent (in) :: x_m
    real(8) :: tmp
    if ((sin(x_m) - x_m) <= (-0.05d0)) then
        tmp = ((0.5d0 + ((-0.5d0) * cos((x_m * 2.0d0)))) - (x_m * x_m)) / (x_m + sin(x_m))
    else
        tmp = x_m * ((x_m * (x_m * 0.027777777777777776d0)) / ((-0.16666666666666666d0) + ((x_m * x_m) * (-0.008333333333333333d0))))
    end if
    code = x_s * tmp
end function
x\_m = Math.abs(x);
x\_s = Math.copySign(1.0, x);
public static double code(double x_s, double x_m) {
	double tmp;
	if ((Math.sin(x_m) - x_m) <= -0.05) {
		tmp = ((0.5 + (-0.5 * Math.cos((x_m * 2.0)))) - (x_m * x_m)) / (x_m + Math.sin(x_m));
	} else {
		tmp = x_m * ((x_m * (x_m * 0.027777777777777776)) / (-0.16666666666666666 + ((x_m * x_m) * -0.008333333333333333)));
	}
	return x_s * tmp;
}
x\_m = math.fabs(x)
x\_s = math.copysign(1.0, x)
def code(x_s, x_m):
	tmp = 0
	if (math.sin(x_m) - x_m) <= -0.05:
		tmp = ((0.5 + (-0.5 * math.cos((x_m * 2.0)))) - (x_m * x_m)) / (x_m + math.sin(x_m))
	else:
		tmp = x_m * ((x_m * (x_m * 0.027777777777777776)) / (-0.16666666666666666 + ((x_m * x_m) * -0.008333333333333333)))
	return x_s * tmp
x\_m = abs(x)
x\_s = copysign(1.0, x)
function code(x_s, x_m)
	tmp = 0.0
	if (Float64(sin(x_m) - x_m) <= -0.05)
		tmp = Float64(Float64(Float64(0.5 + Float64(-0.5 * cos(Float64(x_m * 2.0)))) - Float64(x_m * x_m)) / Float64(x_m + sin(x_m)));
	else
		tmp = Float64(x_m * Float64(Float64(x_m * Float64(x_m * 0.027777777777777776)) / Float64(-0.16666666666666666 + Float64(Float64(x_m * x_m) * -0.008333333333333333))));
	end
	return Float64(x_s * tmp)
end
x\_m = abs(x);
x\_s = sign(x) * abs(1.0);
function tmp_2 = code(x_s, x_m)
	tmp = 0.0;
	if ((sin(x_m) - x_m) <= -0.05)
		tmp = ((0.5 + (-0.5 * cos((x_m * 2.0)))) - (x_m * x_m)) / (x_m + sin(x_m));
	else
		tmp = x_m * ((x_m * (x_m * 0.027777777777777776)) / (-0.16666666666666666 + ((x_m * x_m) * -0.008333333333333333)));
	end
	tmp_2 = x_s * tmp;
end
x\_m = N[Abs[x], $MachinePrecision]
x\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := N[(x$95$s * If[LessEqual[N[(N[Sin[x$95$m], $MachinePrecision] - x$95$m), $MachinePrecision], -0.05], N[(N[(N[(0.5 + N[(-0.5 * N[Cos[N[(x$95$m * 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(x$95$m * x$95$m), $MachinePrecision]), $MachinePrecision] / N[(x$95$m + N[Sin[x$95$m], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(x$95$m * N[(N[(x$95$m * N[(x$95$m * 0.027777777777777776), $MachinePrecision]), $MachinePrecision] / N[(-0.16666666666666666 + N[(N[(x$95$m * x$95$m), $MachinePrecision] * -0.008333333333333333), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]), $MachinePrecision]
\begin{array}{l}
x\_m = \left|x\right|
\\
x\_s = \mathsf{copysign}\left(1, x\right)

\\
x\_s \cdot \begin{array}{l}
\mathbf{if}\;\sin x\_m - x\_m \leq -0.05:\\
\;\;\;\;\frac{\left(0.5 + -0.5 \cdot \cos \left(x\_m \cdot 2\right)\right) - x\_m \cdot x\_m}{x\_m + \sin x\_m}\\

\mathbf{else}:\\
\;\;\;\;x\_m \cdot \frac{x\_m \cdot \left(x\_m \cdot 0.027777777777777776\right)}{-0.16666666666666666 + \left(x\_m \cdot x\_m\right) \cdot -0.008333333333333333}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (-.f64 (sin.f64 x) x) < -0.050000000000000003

    1. Initial program 100.0%

      \[\sin x - x \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. flip--N/A

        \[\leadsto \frac{\sin x \cdot \sin x - x \cdot x}{\color{blue}{\sin x + x}} \]
      2. /-lowering-/.f64N/A

        \[\leadsto \mathsf{/.f64}\left(\left(\sin x \cdot \sin x - x \cdot x\right), \color{blue}{\left(\sin x + x\right)}\right) \]
      3. --lowering--.f64N/A

        \[\leadsto \mathsf{/.f64}\left(\mathsf{\_.f64}\left(\left(\sin x \cdot \sin x\right), \left(x \cdot x\right)\right), \left(\color{blue}{\sin x} + x\right)\right) \]
      4. sqr-sin-aN/A

        \[\leadsto \mathsf{/.f64}\left(\mathsf{\_.f64}\left(\left(\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)\right), \left(x \cdot x\right)\right), \left(\sin \color{blue}{x} + x\right)\right) \]
      5. cancel-sign-sub-invN/A

        \[\leadsto \mathsf{/.f64}\left(\mathsf{\_.f64}\left(\left(\frac{1}{2} + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right) \cdot \cos \left(2 \cdot x\right)\right), \left(x \cdot x\right)\right), \left(\sin \color{blue}{x} + x\right)\right) \]
      6. +-lowering-+.f64N/A

        \[\leadsto \mathsf{/.f64}\left(\mathsf{\_.f64}\left(\mathsf{+.f64}\left(\frac{1}{2}, \left(\left(\mathsf{neg}\left(\frac{1}{2}\right)\right) \cdot \cos \left(2 \cdot x\right)\right)\right), \left(x \cdot x\right)\right), \left(\sin \color{blue}{x} + x\right)\right) \]
      7. *-lowering-*.f64N/A

        \[\leadsto \mathsf{/.f64}\left(\mathsf{\_.f64}\left(\mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(\left(\mathsf{neg}\left(\frac{1}{2}\right)\right), \cos \left(2 \cdot x\right)\right)\right), \left(x \cdot x\right)\right), \left(\sin x + x\right)\right) \]
      8. metadata-evalN/A

        \[\leadsto \mathsf{/.f64}\left(\mathsf{\_.f64}\left(\mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(\frac{-1}{2}, \cos \left(2 \cdot x\right)\right)\right), \left(x \cdot x\right)\right), \left(\sin x + x\right)\right) \]
      9. count-2N/A

        \[\leadsto \mathsf{/.f64}\left(\mathsf{\_.f64}\left(\mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(\frac{-1}{2}, \cos \left(x + x\right)\right)\right), \left(x \cdot x\right)\right), \left(\sin x + x\right)\right) \]
      10. cos-lowering-cos.f64N/A

        \[\leadsto \mathsf{/.f64}\left(\mathsf{\_.f64}\left(\mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(\left(x + x\right)\right)\right)\right), \left(x \cdot x\right)\right), \left(\sin x + x\right)\right) \]
      11. count-2N/A

        \[\leadsto \mathsf{/.f64}\left(\mathsf{\_.f64}\left(\mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(\left(2 \cdot x\right)\right)\right)\right), \left(x \cdot x\right)\right), \left(\sin x + x\right)\right) \]
      12. *-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(\mathsf{\_.f64}\left(\mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(\left(x \cdot 2\right)\right)\right)\right), \left(x \cdot x\right)\right), \left(\sin x + x\right)\right) \]
      13. *-lowering-*.f64N/A

        \[\leadsto \mathsf{/.f64}\left(\mathsf{\_.f64}\left(\mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(\mathsf{*.f64}\left(x, 2\right)\right)\right)\right), \left(x \cdot x\right)\right), \left(\sin x + x\right)\right) \]
      14. *-lowering-*.f64N/A

        \[\leadsto \mathsf{/.f64}\left(\mathsf{\_.f64}\left(\mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(\mathsf{*.f64}\left(x, 2\right)\right)\right)\right), \mathsf{*.f64}\left(x, x\right)\right), \left(\sin x + x\right)\right) \]
      15. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(\mathsf{\_.f64}\left(\mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(\mathsf{*.f64}\left(x, 2\right)\right)\right)\right), \mathsf{*.f64}\left(x, x\right)\right), \left(x + \color{blue}{\sin x}\right)\right) \]
      16. +-lowering-+.f64N/A

        \[\leadsto \mathsf{/.f64}\left(\mathsf{\_.f64}\left(\mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(\mathsf{*.f64}\left(x, 2\right)\right)\right)\right), \mathsf{*.f64}\left(x, x\right)\right), \mathsf{+.f64}\left(x, \color{blue}{\sin x}\right)\right) \]
      17. sin-lowering-sin.f64100.0%

        \[\leadsto \mathsf{/.f64}\left(\mathsf{\_.f64}\left(\mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(\mathsf{*.f64}\left(x, 2\right)\right)\right)\right), \mathsf{*.f64}\left(x, x\right)\right), \mathsf{+.f64}\left(x, \mathsf{sin.f64}\left(x\right)\right)\right) \]
    4. Applied egg-rr100.0%

      \[\leadsto \color{blue}{\frac{\left(0.5 + -0.5 \cdot \cos \left(x \cdot 2\right)\right) - x \cdot x}{x + \sin x}} \]

    if -0.050000000000000003 < (-.f64 (sin.f64 x) x)

    1. Initial program 73.5%

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

      \[\leadsto \color{blue}{{x}^{3} \cdot \left(\frac{1}{120} \cdot {x}^{2} - \frac{1}{6}\right)} \]
    4. Step-by-step derivation
      1. cube-multN/A

        \[\leadsto \left(x \cdot \left(x \cdot x\right)\right) \cdot \left(\color{blue}{\frac{1}{120} \cdot {x}^{2}} - \frac{1}{6}\right) \]
      2. unpow2N/A

        \[\leadsto \left(x \cdot {x}^{2}\right) \cdot \left(\frac{1}{120} \cdot \color{blue}{{x}^{2}} - \frac{1}{6}\right) \]
      3. associate-*r*N/A

        \[\leadsto x \cdot \color{blue}{\left({x}^{2} \cdot \left(\frac{1}{120} \cdot {x}^{2} - \frac{1}{6}\right)\right)} \]
      4. *-lowering-*.f64N/A

        \[\leadsto \mathsf{*.f64}\left(x, \color{blue}{\left({x}^{2} \cdot \left(\frac{1}{120} \cdot {x}^{2} - \frac{1}{6}\right)\right)}\right) \]
      5. *-lowering-*.f64N/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\left(\frac{1}{120} \cdot {x}^{2} - \frac{1}{6}\right)}\right)\right) \]
      6. unpow2N/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\left(x \cdot x\right), \left(\color{blue}{\frac{1}{120} \cdot {x}^{2}} - \frac{1}{6}\right)\right)\right) \]
      7. *-lowering-*.f64N/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{\frac{1}{120} \cdot {x}^{2}} - \frac{1}{6}\right)\right)\right) \]
      8. sub-negN/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\frac{1}{120} \cdot {x}^{2} + \color{blue}{\left(\mathsf{neg}\left(\frac{1}{6}\right)\right)}\right)\right)\right) \]
      9. metadata-evalN/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\frac{1}{120} \cdot {x}^{2} + \frac{-1}{6}\right)\right)\right) \]
      10. +-commutativeN/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\frac{-1}{6} + \color{blue}{\frac{1}{120} \cdot {x}^{2}}\right)\right)\right) \]
      11. +-lowering-+.f64N/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{-1}{6}, \color{blue}{\left(\frac{1}{120} \cdot {x}^{2}\right)}\right)\right)\right) \]
      12. *-lowering-*.f64N/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\frac{1}{120}, \color{blue}{\left({x}^{2}\right)}\right)\right)\right)\right) \]
      13. unpow2N/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\frac{1}{120}, \left(x \cdot \color{blue}{x}\right)\right)\right)\right)\right) \]
      14. *-lowering-*.f6497.3%

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\frac{1}{120}, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right)\right)\right) \]
    5. Simplified97.3%

      \[\leadsto \color{blue}{x \cdot \left(\left(x \cdot x\right) \cdot \left(-0.16666666666666666 + 0.008333333333333333 \cdot \left(x \cdot x\right)\right)\right)} \]
    6. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \mathsf{*.f64}\left(x, \left(\left(\frac{-1}{6} + \frac{1}{120} \cdot \left(x \cdot x\right)\right) \cdot \color{blue}{\left(x \cdot x\right)}\right)\right) \]
      2. flip-+N/A

        \[\leadsto \mathsf{*.f64}\left(x, \left(\frac{\frac{-1}{6} \cdot \frac{-1}{6} - \left(\frac{1}{120} \cdot \left(x \cdot x\right)\right) \cdot \left(\frac{1}{120} \cdot \left(x \cdot x\right)\right)}{\frac{-1}{6} - \frac{1}{120} \cdot \left(x \cdot x\right)} \cdot \left(\color{blue}{x} \cdot x\right)\right)\right) \]
      3. associate-*l/N/A

        \[\leadsto \mathsf{*.f64}\left(x, \left(\frac{\left(\frac{-1}{6} \cdot \frac{-1}{6} - \left(\frac{1}{120} \cdot \left(x \cdot x\right)\right) \cdot \left(\frac{1}{120} \cdot \left(x \cdot x\right)\right)\right) \cdot \left(x \cdot x\right)}{\color{blue}{\frac{-1}{6} - \frac{1}{120} \cdot \left(x \cdot x\right)}}\right)\right) \]
      4. /-lowering-/.f64N/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{/.f64}\left(\left(\left(\frac{-1}{6} \cdot \frac{-1}{6} - \left(\frac{1}{120} \cdot \left(x \cdot x\right)\right) \cdot \left(\frac{1}{120} \cdot \left(x \cdot x\right)\right)\right) \cdot \left(x \cdot x\right)\right), \color{blue}{\left(\frac{-1}{6} - \frac{1}{120} \cdot \left(x \cdot x\right)\right)}\right)\right) \]
    7. Applied egg-rr97.3%

      \[\leadsto x \cdot \color{blue}{\frac{\left(0.027777777777777776 - 6.944444444444444 \cdot 10^{-5} \cdot \left(\left(x \cdot \left(x \cdot x\right)\right) \cdot x\right)\right) \cdot \left(x \cdot x\right)}{-0.16666666666666666 + -0.008333333333333333 \cdot \left(x \cdot x\right)}} \]
    8. Taylor expanded in x around 0

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{/.f64}\left(\color{blue}{\left(\frac{1}{36} \cdot {x}^{2}\right)}, \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\frac{-1}{120}, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)\right) \]
    9. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{/.f64}\left(\left({x}^{2} \cdot \frac{1}{36}\right), \mathsf{+.f64}\left(\color{blue}{\frac{-1}{6}}, \mathsf{*.f64}\left(\frac{-1}{120}, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)\right) \]
      2. unpow2N/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{/.f64}\left(\left(\left(x \cdot x\right) \cdot \frac{1}{36}\right), \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\frac{-1}{120}, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)\right) \]
      3. associate-*l*N/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{/.f64}\left(\left(x \cdot \left(x \cdot \frac{1}{36}\right)\right), \mathsf{+.f64}\left(\color{blue}{\frac{-1}{6}}, \mathsf{*.f64}\left(\frac{-1}{120}, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)\right) \]
      4. *-lowering-*.f64N/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, \left(x \cdot \frac{1}{36}\right)\right), \mathsf{+.f64}\left(\color{blue}{\frac{-1}{6}}, \mathsf{*.f64}\left(\frac{-1}{120}, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)\right) \]
      5. *-lowering-*.f6497.7%

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \frac{1}{36}\right)\right), \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\frac{-1}{120}, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)\right) \]
    10. Simplified97.7%

      \[\leadsto x \cdot \frac{\color{blue}{x \cdot \left(x \cdot 0.027777777777777776\right)}}{-0.16666666666666666 + -0.008333333333333333 \cdot \left(x \cdot x\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification97.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\sin x - x \leq -0.05:\\ \;\;\;\;\frac{\left(0.5 + -0.5 \cdot \cos \left(x \cdot 2\right)\right) - x \cdot x}{x + \sin x}\\ \mathbf{else}:\\ \;\;\;\;x \cdot \frac{x \cdot \left(x \cdot 0.027777777777777776\right)}{-0.16666666666666666 + \left(x \cdot x\right) \cdot -0.008333333333333333}\\ \end{array} \]
  5. Add Preprocessing

Alternative 2: 99.5% accurate, 0.5× speedup?

\[\begin{array}{l} x\_m = \left|x\right| \\ x\_s = \mathsf{copysign}\left(1, x\right) \\ \begin{array}{l} t_0 := \sin x\_m - x\_m\\ x\_s \cdot \begin{array}{l} \mathbf{if}\;t\_0 \leq -0.05:\\ \;\;\;\;t\_0\\ \mathbf{else}:\\ \;\;\;\;x\_m \cdot \frac{x\_m \cdot \left(x\_m \cdot 0.027777777777777776\right)}{-0.16666666666666666 + \left(x\_m \cdot x\_m\right) \cdot -0.008333333333333333}\\ \end{array} \end{array} \end{array} \]
x\_m = (fabs.f64 x)
x\_s = (copysign.f64 #s(literal 1 binary64) x)
(FPCore (x_s x_m)
 :precision binary64
 (let* ((t_0 (- (sin x_m) x_m)))
   (*
    x_s
    (if (<= t_0 -0.05)
      t_0
      (*
       x_m
       (/
        (* x_m (* x_m 0.027777777777777776))
        (+ -0.16666666666666666 (* (* x_m x_m) -0.008333333333333333))))))))
x\_m = fabs(x);
x\_s = copysign(1.0, x);
double code(double x_s, double x_m) {
	double t_0 = sin(x_m) - x_m;
	double tmp;
	if (t_0 <= -0.05) {
		tmp = t_0;
	} else {
		tmp = x_m * ((x_m * (x_m * 0.027777777777777776)) / (-0.16666666666666666 + ((x_m * x_m) * -0.008333333333333333)));
	}
	return x_s * tmp;
}
x\_m = abs(x)
x\_s = copysign(1.0d0, x)
real(8) function code(x_s, x_m)
    real(8), intent (in) :: x_s
    real(8), intent (in) :: x_m
    real(8) :: t_0
    real(8) :: tmp
    t_0 = sin(x_m) - x_m
    if (t_0 <= (-0.05d0)) then
        tmp = t_0
    else
        tmp = x_m * ((x_m * (x_m * 0.027777777777777776d0)) / ((-0.16666666666666666d0) + ((x_m * x_m) * (-0.008333333333333333d0))))
    end if
    code = x_s * tmp
end function
x\_m = Math.abs(x);
x\_s = Math.copySign(1.0, x);
public static double code(double x_s, double x_m) {
	double t_0 = Math.sin(x_m) - x_m;
	double tmp;
	if (t_0 <= -0.05) {
		tmp = t_0;
	} else {
		tmp = x_m * ((x_m * (x_m * 0.027777777777777776)) / (-0.16666666666666666 + ((x_m * x_m) * -0.008333333333333333)));
	}
	return x_s * tmp;
}
x\_m = math.fabs(x)
x\_s = math.copysign(1.0, x)
def code(x_s, x_m):
	t_0 = math.sin(x_m) - x_m
	tmp = 0
	if t_0 <= -0.05:
		tmp = t_0
	else:
		tmp = x_m * ((x_m * (x_m * 0.027777777777777776)) / (-0.16666666666666666 + ((x_m * x_m) * -0.008333333333333333)))
	return x_s * tmp
x\_m = abs(x)
x\_s = copysign(1.0, x)
function code(x_s, x_m)
	t_0 = Float64(sin(x_m) - x_m)
	tmp = 0.0
	if (t_0 <= -0.05)
		tmp = t_0;
	else
		tmp = Float64(x_m * Float64(Float64(x_m * Float64(x_m * 0.027777777777777776)) / Float64(-0.16666666666666666 + Float64(Float64(x_m * x_m) * -0.008333333333333333))));
	end
	return Float64(x_s * tmp)
end
x\_m = abs(x);
x\_s = sign(x) * abs(1.0);
function tmp_2 = code(x_s, x_m)
	t_0 = sin(x_m) - x_m;
	tmp = 0.0;
	if (t_0 <= -0.05)
		tmp = t_0;
	else
		tmp = x_m * ((x_m * (x_m * 0.027777777777777776)) / (-0.16666666666666666 + ((x_m * x_m) * -0.008333333333333333)));
	end
	tmp_2 = x_s * tmp;
end
x\_m = N[Abs[x], $MachinePrecision]
x\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := Block[{t$95$0 = N[(N[Sin[x$95$m], $MachinePrecision] - x$95$m), $MachinePrecision]}, N[(x$95$s * If[LessEqual[t$95$0, -0.05], t$95$0, N[(x$95$m * N[(N[(x$95$m * N[(x$95$m * 0.027777777777777776), $MachinePrecision]), $MachinePrecision] / N[(-0.16666666666666666 + N[(N[(x$95$m * x$95$m), $MachinePrecision] * -0.008333333333333333), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]), $MachinePrecision]]
\begin{array}{l}
x\_m = \left|x\right|
\\
x\_s = \mathsf{copysign}\left(1, x\right)

\\
\begin{array}{l}
t_0 := \sin x\_m - x\_m\\
x\_s \cdot \begin{array}{l}
\mathbf{if}\;t\_0 \leq -0.05:\\
\;\;\;\;t\_0\\

\mathbf{else}:\\
\;\;\;\;x\_m \cdot \frac{x\_m \cdot \left(x\_m \cdot 0.027777777777777776\right)}{-0.16666666666666666 + \left(x\_m \cdot x\_m\right) \cdot -0.008333333333333333}\\


\end{array}
\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (-.f64 (sin.f64 x) x) < -0.050000000000000003

    1. Initial program 100.0%

      \[\sin x - x \]
    2. Add Preprocessing

    if -0.050000000000000003 < (-.f64 (sin.f64 x) x)

    1. Initial program 73.5%

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

      \[\leadsto \color{blue}{{x}^{3} \cdot \left(\frac{1}{120} \cdot {x}^{2} - \frac{1}{6}\right)} \]
    4. Step-by-step derivation
      1. cube-multN/A

        \[\leadsto \left(x \cdot \left(x \cdot x\right)\right) \cdot \left(\color{blue}{\frac{1}{120} \cdot {x}^{2}} - \frac{1}{6}\right) \]
      2. unpow2N/A

        \[\leadsto \left(x \cdot {x}^{2}\right) \cdot \left(\frac{1}{120} \cdot \color{blue}{{x}^{2}} - \frac{1}{6}\right) \]
      3. associate-*r*N/A

        \[\leadsto x \cdot \color{blue}{\left({x}^{2} \cdot \left(\frac{1}{120} \cdot {x}^{2} - \frac{1}{6}\right)\right)} \]
      4. *-lowering-*.f64N/A

        \[\leadsto \mathsf{*.f64}\left(x, \color{blue}{\left({x}^{2} \cdot \left(\frac{1}{120} \cdot {x}^{2} - \frac{1}{6}\right)\right)}\right) \]
      5. *-lowering-*.f64N/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\left(\frac{1}{120} \cdot {x}^{2} - \frac{1}{6}\right)}\right)\right) \]
      6. unpow2N/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\left(x \cdot x\right), \left(\color{blue}{\frac{1}{120} \cdot {x}^{2}} - \frac{1}{6}\right)\right)\right) \]
      7. *-lowering-*.f64N/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{\frac{1}{120} \cdot {x}^{2}} - \frac{1}{6}\right)\right)\right) \]
      8. sub-negN/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\frac{1}{120} \cdot {x}^{2} + \color{blue}{\left(\mathsf{neg}\left(\frac{1}{6}\right)\right)}\right)\right)\right) \]
      9. metadata-evalN/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\frac{1}{120} \cdot {x}^{2} + \frac{-1}{6}\right)\right)\right) \]
      10. +-commutativeN/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\frac{-1}{6} + \color{blue}{\frac{1}{120} \cdot {x}^{2}}\right)\right)\right) \]
      11. +-lowering-+.f64N/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{-1}{6}, \color{blue}{\left(\frac{1}{120} \cdot {x}^{2}\right)}\right)\right)\right) \]
      12. *-lowering-*.f64N/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\frac{1}{120}, \color{blue}{\left({x}^{2}\right)}\right)\right)\right)\right) \]
      13. unpow2N/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\frac{1}{120}, \left(x \cdot \color{blue}{x}\right)\right)\right)\right)\right) \]
      14. *-lowering-*.f6497.3%

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\frac{1}{120}, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right)\right)\right) \]
    5. Simplified97.3%

      \[\leadsto \color{blue}{x \cdot \left(\left(x \cdot x\right) \cdot \left(-0.16666666666666666 + 0.008333333333333333 \cdot \left(x \cdot x\right)\right)\right)} \]
    6. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \mathsf{*.f64}\left(x, \left(\left(\frac{-1}{6} + \frac{1}{120} \cdot \left(x \cdot x\right)\right) \cdot \color{blue}{\left(x \cdot x\right)}\right)\right) \]
      2. flip-+N/A

        \[\leadsto \mathsf{*.f64}\left(x, \left(\frac{\frac{-1}{6} \cdot \frac{-1}{6} - \left(\frac{1}{120} \cdot \left(x \cdot x\right)\right) \cdot \left(\frac{1}{120} \cdot \left(x \cdot x\right)\right)}{\frac{-1}{6} - \frac{1}{120} \cdot \left(x \cdot x\right)} \cdot \left(\color{blue}{x} \cdot x\right)\right)\right) \]
      3. associate-*l/N/A

        \[\leadsto \mathsf{*.f64}\left(x, \left(\frac{\left(\frac{-1}{6} \cdot \frac{-1}{6} - \left(\frac{1}{120} \cdot \left(x \cdot x\right)\right) \cdot \left(\frac{1}{120} \cdot \left(x \cdot x\right)\right)\right) \cdot \left(x \cdot x\right)}{\color{blue}{\frac{-1}{6} - \frac{1}{120} \cdot \left(x \cdot x\right)}}\right)\right) \]
      4. /-lowering-/.f64N/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{/.f64}\left(\left(\left(\frac{-1}{6} \cdot \frac{-1}{6} - \left(\frac{1}{120} \cdot \left(x \cdot x\right)\right) \cdot \left(\frac{1}{120} \cdot \left(x \cdot x\right)\right)\right) \cdot \left(x \cdot x\right)\right), \color{blue}{\left(\frac{-1}{6} - \frac{1}{120} \cdot \left(x \cdot x\right)\right)}\right)\right) \]
    7. Applied egg-rr97.3%

      \[\leadsto x \cdot \color{blue}{\frac{\left(0.027777777777777776 - 6.944444444444444 \cdot 10^{-5} \cdot \left(\left(x \cdot \left(x \cdot x\right)\right) \cdot x\right)\right) \cdot \left(x \cdot x\right)}{-0.16666666666666666 + -0.008333333333333333 \cdot \left(x \cdot x\right)}} \]
    8. Taylor expanded in x around 0

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{/.f64}\left(\color{blue}{\left(\frac{1}{36} \cdot {x}^{2}\right)}, \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\frac{-1}{120}, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)\right) \]
    9. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{/.f64}\left(\left({x}^{2} \cdot \frac{1}{36}\right), \mathsf{+.f64}\left(\color{blue}{\frac{-1}{6}}, \mathsf{*.f64}\left(\frac{-1}{120}, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)\right) \]
      2. unpow2N/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{/.f64}\left(\left(\left(x \cdot x\right) \cdot \frac{1}{36}\right), \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\frac{-1}{120}, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)\right) \]
      3. associate-*l*N/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{/.f64}\left(\left(x \cdot \left(x \cdot \frac{1}{36}\right)\right), \mathsf{+.f64}\left(\color{blue}{\frac{-1}{6}}, \mathsf{*.f64}\left(\frac{-1}{120}, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)\right) \]
      4. *-lowering-*.f64N/A

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, \left(x \cdot \frac{1}{36}\right)\right), \mathsf{+.f64}\left(\color{blue}{\frac{-1}{6}}, \mathsf{*.f64}\left(\frac{-1}{120}, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)\right) \]
      5. *-lowering-*.f6497.7%

        \[\leadsto \mathsf{*.f64}\left(x, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \frac{1}{36}\right)\right), \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\frac{-1}{120}, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)\right) \]
    10. Simplified97.7%

      \[\leadsto x \cdot \frac{\color{blue}{x \cdot \left(x \cdot 0.027777777777777776\right)}}{-0.16666666666666666 + -0.008333333333333333 \cdot \left(x \cdot x\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification97.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\sin x - x \leq -0.05:\\ \;\;\;\;\sin x - x\\ \mathbf{else}:\\ \;\;\;\;x \cdot \frac{x \cdot \left(x \cdot 0.027777777777777776\right)}{-0.16666666666666666 + \left(x \cdot x\right) \cdot -0.008333333333333333}\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 98.6% accurate, 6.9× speedup?

\[\begin{array}{l} x\_m = \left|x\right| \\ x\_s = \mathsf{copysign}\left(1, x\right) \\ x\_s \cdot \left(x\_m \cdot \frac{x\_m \cdot \left(x\_m \cdot 0.027777777777777776\right)}{-0.16666666666666666 + \left(x\_m \cdot x\_m\right) \cdot -0.008333333333333333}\right) \end{array} \]
x\_m = (fabs.f64 x)
x\_s = (copysign.f64 #s(literal 1 binary64) x)
(FPCore (x_s x_m)
 :precision binary64
 (*
  x_s
  (*
   x_m
   (/
    (* x_m (* x_m 0.027777777777777776))
    (+ -0.16666666666666666 (* (* x_m x_m) -0.008333333333333333))))))
x\_m = fabs(x);
x\_s = copysign(1.0, x);
double code(double x_s, double x_m) {
	return x_s * (x_m * ((x_m * (x_m * 0.027777777777777776)) / (-0.16666666666666666 + ((x_m * x_m) * -0.008333333333333333))));
}
x\_m = abs(x)
x\_s = copysign(1.0d0, x)
real(8) function code(x_s, x_m)
    real(8), intent (in) :: x_s
    real(8), intent (in) :: x_m
    code = x_s * (x_m * ((x_m * (x_m * 0.027777777777777776d0)) / ((-0.16666666666666666d0) + ((x_m * x_m) * (-0.008333333333333333d0)))))
end function
x\_m = Math.abs(x);
x\_s = Math.copySign(1.0, x);
public static double code(double x_s, double x_m) {
	return x_s * (x_m * ((x_m * (x_m * 0.027777777777777776)) / (-0.16666666666666666 + ((x_m * x_m) * -0.008333333333333333))));
}
x\_m = math.fabs(x)
x\_s = math.copysign(1.0, x)
def code(x_s, x_m):
	return x_s * (x_m * ((x_m * (x_m * 0.027777777777777776)) / (-0.16666666666666666 + ((x_m * x_m) * -0.008333333333333333))))
x\_m = abs(x)
x\_s = copysign(1.0, x)
function code(x_s, x_m)
	return Float64(x_s * Float64(x_m * Float64(Float64(x_m * Float64(x_m * 0.027777777777777776)) / Float64(-0.16666666666666666 + Float64(Float64(x_m * x_m) * -0.008333333333333333)))))
end
x\_m = abs(x);
x\_s = sign(x) * abs(1.0);
function tmp = code(x_s, x_m)
	tmp = x_s * (x_m * ((x_m * (x_m * 0.027777777777777776)) / (-0.16666666666666666 + ((x_m * x_m) * -0.008333333333333333))));
end
x\_m = N[Abs[x], $MachinePrecision]
x\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := N[(x$95$s * N[(x$95$m * N[(N[(x$95$m * N[(x$95$m * 0.027777777777777776), $MachinePrecision]), $MachinePrecision] / N[(-0.16666666666666666 + N[(N[(x$95$m * x$95$m), $MachinePrecision] * -0.008333333333333333), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
x\_m = \left|x\right|
\\
x\_s = \mathsf{copysign}\left(1, x\right)

\\
x\_s \cdot \left(x\_m \cdot \frac{x\_m \cdot \left(x\_m \cdot 0.027777777777777776\right)}{-0.16666666666666666 + \left(x\_m \cdot x\_m\right) \cdot -0.008333333333333333}\right)
\end{array}
Derivation
  1. Initial program 73.6%

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

    \[\leadsto \color{blue}{{x}^{3} \cdot \left(\frac{1}{120} \cdot {x}^{2} - \frac{1}{6}\right)} \]
  4. Step-by-step derivation
    1. cube-multN/A

      \[\leadsto \left(x \cdot \left(x \cdot x\right)\right) \cdot \left(\color{blue}{\frac{1}{120} \cdot {x}^{2}} - \frac{1}{6}\right) \]
    2. unpow2N/A

      \[\leadsto \left(x \cdot {x}^{2}\right) \cdot \left(\frac{1}{120} \cdot \color{blue}{{x}^{2}} - \frac{1}{6}\right) \]
    3. associate-*r*N/A

      \[\leadsto x \cdot \color{blue}{\left({x}^{2} \cdot \left(\frac{1}{120} \cdot {x}^{2} - \frac{1}{6}\right)\right)} \]
    4. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \color{blue}{\left({x}^{2} \cdot \left(\frac{1}{120} \cdot {x}^{2} - \frac{1}{6}\right)\right)}\right) \]
    5. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\left(\frac{1}{120} \cdot {x}^{2} - \frac{1}{6}\right)}\right)\right) \]
    6. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\left(x \cdot x\right), \left(\color{blue}{\frac{1}{120} \cdot {x}^{2}} - \frac{1}{6}\right)\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{\frac{1}{120} \cdot {x}^{2}} - \frac{1}{6}\right)\right)\right) \]
    8. sub-negN/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\frac{1}{120} \cdot {x}^{2} + \color{blue}{\left(\mathsf{neg}\left(\frac{1}{6}\right)\right)}\right)\right)\right) \]
    9. metadata-evalN/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\frac{1}{120} \cdot {x}^{2} + \frac{-1}{6}\right)\right)\right) \]
    10. +-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\frac{-1}{6} + \color{blue}{\frac{1}{120} \cdot {x}^{2}}\right)\right)\right) \]
    11. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{-1}{6}, \color{blue}{\left(\frac{1}{120} \cdot {x}^{2}\right)}\right)\right)\right) \]
    12. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\frac{1}{120}, \color{blue}{\left({x}^{2}\right)}\right)\right)\right)\right) \]
    13. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\frac{1}{120}, \left(x \cdot \color{blue}{x}\right)\right)\right)\right)\right) \]
    14. *-lowering-*.f6496.9%

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\frac{1}{120}, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right)\right)\right) \]
  5. Simplified96.9%

    \[\leadsto \color{blue}{x \cdot \left(\left(x \cdot x\right) \cdot \left(-0.16666666666666666 + 0.008333333333333333 \cdot \left(x \cdot x\right)\right)\right)} \]
  6. Step-by-step derivation
    1. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(x, \left(\left(\frac{-1}{6} + \frac{1}{120} \cdot \left(x \cdot x\right)\right) \cdot \color{blue}{\left(x \cdot x\right)}\right)\right) \]
    2. flip-+N/A

      \[\leadsto \mathsf{*.f64}\left(x, \left(\frac{\frac{-1}{6} \cdot \frac{-1}{6} - \left(\frac{1}{120} \cdot \left(x \cdot x\right)\right) \cdot \left(\frac{1}{120} \cdot \left(x \cdot x\right)\right)}{\frac{-1}{6} - \frac{1}{120} \cdot \left(x \cdot x\right)} \cdot \left(\color{blue}{x} \cdot x\right)\right)\right) \]
    3. associate-*l/N/A

      \[\leadsto \mathsf{*.f64}\left(x, \left(\frac{\left(\frac{-1}{6} \cdot \frac{-1}{6} - \left(\frac{1}{120} \cdot \left(x \cdot x\right)\right) \cdot \left(\frac{1}{120} \cdot \left(x \cdot x\right)\right)\right) \cdot \left(x \cdot x\right)}{\color{blue}{\frac{-1}{6} - \frac{1}{120} \cdot \left(x \cdot x\right)}}\right)\right) \]
    4. /-lowering-/.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{/.f64}\left(\left(\left(\frac{-1}{6} \cdot \frac{-1}{6} - \left(\frac{1}{120} \cdot \left(x \cdot x\right)\right) \cdot \left(\frac{1}{120} \cdot \left(x \cdot x\right)\right)\right) \cdot \left(x \cdot x\right)\right), \color{blue}{\left(\frac{-1}{6} - \frac{1}{120} \cdot \left(x \cdot x\right)\right)}\right)\right) \]
  7. Applied egg-rr96.9%

    \[\leadsto x \cdot \color{blue}{\frac{\left(0.027777777777777776 - 6.944444444444444 \cdot 10^{-5} \cdot \left(\left(x \cdot \left(x \cdot x\right)\right) \cdot x\right)\right) \cdot \left(x \cdot x\right)}{-0.16666666666666666 + -0.008333333333333333 \cdot \left(x \cdot x\right)}} \]
  8. Taylor expanded in x around 0

    \[\leadsto \mathsf{*.f64}\left(x, \mathsf{/.f64}\left(\color{blue}{\left(\frac{1}{36} \cdot {x}^{2}\right)}, \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\frac{-1}{120}, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)\right) \]
  9. Step-by-step derivation
    1. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{/.f64}\left(\left({x}^{2} \cdot \frac{1}{36}\right), \mathsf{+.f64}\left(\color{blue}{\frac{-1}{6}}, \mathsf{*.f64}\left(\frac{-1}{120}, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)\right) \]
    2. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{/.f64}\left(\left(\left(x \cdot x\right) \cdot \frac{1}{36}\right), \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\frac{-1}{120}, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)\right) \]
    3. associate-*l*N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{/.f64}\left(\left(x \cdot \left(x \cdot \frac{1}{36}\right)\right), \mathsf{+.f64}\left(\color{blue}{\frac{-1}{6}}, \mathsf{*.f64}\left(\frac{-1}{120}, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)\right) \]
    4. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, \left(x \cdot \frac{1}{36}\right)\right), \mathsf{+.f64}\left(\color{blue}{\frac{-1}{6}}, \mathsf{*.f64}\left(\frac{-1}{120}, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)\right) \]
    5. *-lowering-*.f6497.4%

      \[\leadsto \mathsf{*.f64}\left(x, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \frac{1}{36}\right)\right), \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\frac{-1}{120}, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)\right) \]
  10. Simplified97.4%

    \[\leadsto x \cdot \frac{\color{blue}{x \cdot \left(x \cdot 0.027777777777777776\right)}}{-0.16666666666666666 + -0.008333333333333333 \cdot \left(x \cdot x\right)} \]
  11. Final simplification97.4%

    \[\leadsto x \cdot \frac{x \cdot \left(x \cdot 0.027777777777777776\right)}{-0.16666666666666666 + \left(x \cdot x\right) \cdot -0.008333333333333333} \]
  12. Add Preprocessing

Alternative 4: 98.1% accurate, 14.7× speedup?

\[\begin{array}{l} x\_m = \left|x\right| \\ x\_s = \mathsf{copysign}\left(1, x\right) \\ x\_s \cdot \left(\left(x\_m \cdot x\_m\right) \cdot \left(x\_m \cdot -0.16666666666666666\right)\right) \end{array} \]
x\_m = (fabs.f64 x)
x\_s = (copysign.f64 #s(literal 1 binary64) x)
(FPCore (x_s x_m)
 :precision binary64
 (* x_s (* (* x_m x_m) (* x_m -0.16666666666666666))))
x\_m = fabs(x);
x\_s = copysign(1.0, x);
double code(double x_s, double x_m) {
	return x_s * ((x_m * x_m) * (x_m * -0.16666666666666666));
}
x\_m = abs(x)
x\_s = copysign(1.0d0, x)
real(8) function code(x_s, x_m)
    real(8), intent (in) :: x_s
    real(8), intent (in) :: x_m
    code = x_s * ((x_m * x_m) * (x_m * (-0.16666666666666666d0)))
end function
x\_m = Math.abs(x);
x\_s = Math.copySign(1.0, x);
public static double code(double x_s, double x_m) {
	return x_s * ((x_m * x_m) * (x_m * -0.16666666666666666));
}
x\_m = math.fabs(x)
x\_s = math.copysign(1.0, x)
def code(x_s, x_m):
	return x_s * ((x_m * x_m) * (x_m * -0.16666666666666666))
x\_m = abs(x)
x\_s = copysign(1.0, x)
function code(x_s, x_m)
	return Float64(x_s * Float64(Float64(x_m * x_m) * Float64(x_m * -0.16666666666666666)))
end
x\_m = abs(x);
x\_s = sign(x) * abs(1.0);
function tmp = code(x_s, x_m)
	tmp = x_s * ((x_m * x_m) * (x_m * -0.16666666666666666));
end
x\_m = N[Abs[x], $MachinePrecision]
x\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := N[(x$95$s * N[(N[(x$95$m * x$95$m), $MachinePrecision] * N[(x$95$m * -0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
x\_m = \left|x\right|
\\
x\_s = \mathsf{copysign}\left(1, x\right)

\\
x\_s \cdot \left(\left(x\_m \cdot x\_m\right) \cdot \left(x\_m \cdot -0.16666666666666666\right)\right)
\end{array}
Derivation
  1. Initial program 73.6%

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

    \[\leadsto \color{blue}{\frac{-1}{6} \cdot {x}^{3}} \]
  4. Step-by-step derivation
    1. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\frac{-1}{6}, \color{blue}{\left({x}^{3}\right)}\right) \]
    2. cube-multN/A

      \[\leadsto \mathsf{*.f64}\left(\frac{-1}{6}, \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)\right) \]
    3. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(\frac{-1}{6}, \left(x \cdot {x}^{\color{blue}{2}}\right)\right) \]
    4. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(x, \color{blue}{\left({x}^{2}\right)}\right)\right) \]
    5. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(x, \left(x \cdot \color{blue}{x}\right)\right)\right) \]
    6. *-lowering-*.f6496.9%

      \[\leadsto \mathsf{*.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right) \]
  5. Simplified96.9%

    \[\leadsto \color{blue}{-0.16666666666666666 \cdot \left(x \cdot \left(x \cdot x\right)\right)} \]
  6. Step-by-step derivation
    1. associate-*r*N/A

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

      \[\leadsto \left(x \cdot x\right) \cdot \color{blue}{\left(\frac{-1}{6} \cdot x\right)} \]
    3. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\left(x \cdot x\right), \color{blue}{\left(\frac{-1}{6} \cdot x\right)}\right) \]
    4. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{\frac{-1}{6}} \cdot x\right)\right) \]
    5. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(x \cdot \color{blue}{\frac{-1}{6}}\right)\right) \]
    6. *-lowering-*.f6496.9%

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{*.f64}\left(x, \color{blue}{\frac{-1}{6}}\right)\right) \]
  7. Applied egg-rr96.9%

    \[\leadsto \color{blue}{\left(x \cdot x\right) \cdot \left(x \cdot -0.16666666666666666\right)} \]
  8. Add Preprocessing

Alternative 5: 98.1% accurate, 14.7× speedup?

\[\begin{array}{l} x\_m = \left|x\right| \\ x\_s = \mathsf{copysign}\left(1, x\right) \\ x\_s \cdot \left(-0.16666666666666666 \cdot \left(x\_m \cdot \left(x\_m \cdot x\_m\right)\right)\right) \end{array} \]
x\_m = (fabs.f64 x)
x\_s = (copysign.f64 #s(literal 1 binary64) x)
(FPCore (x_s x_m)
 :precision binary64
 (* x_s (* -0.16666666666666666 (* x_m (* x_m x_m)))))
x\_m = fabs(x);
x\_s = copysign(1.0, x);
double code(double x_s, double x_m) {
	return x_s * (-0.16666666666666666 * (x_m * (x_m * x_m)));
}
x\_m = abs(x)
x\_s = copysign(1.0d0, x)
real(8) function code(x_s, x_m)
    real(8), intent (in) :: x_s
    real(8), intent (in) :: x_m
    code = x_s * ((-0.16666666666666666d0) * (x_m * (x_m * x_m)))
end function
x\_m = Math.abs(x);
x\_s = Math.copySign(1.0, x);
public static double code(double x_s, double x_m) {
	return x_s * (-0.16666666666666666 * (x_m * (x_m * x_m)));
}
x\_m = math.fabs(x)
x\_s = math.copysign(1.0, x)
def code(x_s, x_m):
	return x_s * (-0.16666666666666666 * (x_m * (x_m * x_m)))
x\_m = abs(x)
x\_s = copysign(1.0, x)
function code(x_s, x_m)
	return Float64(x_s * Float64(-0.16666666666666666 * Float64(x_m * Float64(x_m * x_m))))
end
x\_m = abs(x);
x\_s = sign(x) * abs(1.0);
function tmp = code(x_s, x_m)
	tmp = x_s * (-0.16666666666666666 * (x_m * (x_m * x_m)));
end
x\_m = N[Abs[x], $MachinePrecision]
x\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := N[(x$95$s * N[(-0.16666666666666666 * N[(x$95$m * N[(x$95$m * x$95$m), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
x\_m = \left|x\right|
\\
x\_s = \mathsf{copysign}\left(1, x\right)

\\
x\_s \cdot \left(-0.16666666666666666 \cdot \left(x\_m \cdot \left(x\_m \cdot x\_m\right)\right)\right)
\end{array}
Derivation
  1. Initial program 73.6%

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

    \[\leadsto \color{blue}{\frac{-1}{6} \cdot {x}^{3}} \]
  4. Step-by-step derivation
    1. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\frac{-1}{6}, \color{blue}{\left({x}^{3}\right)}\right) \]
    2. cube-multN/A

      \[\leadsto \mathsf{*.f64}\left(\frac{-1}{6}, \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)\right) \]
    3. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(\frac{-1}{6}, \left(x \cdot {x}^{\color{blue}{2}}\right)\right) \]
    4. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(x, \color{blue}{\left({x}^{2}\right)}\right)\right) \]
    5. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(x, \left(x \cdot \color{blue}{x}\right)\right)\right) \]
    6. *-lowering-*.f6496.9%

      \[\leadsto \mathsf{*.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right) \]
  5. Simplified96.9%

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

Alternative 6: 67.2% accurate, 103.0× speedup?

\[\begin{array}{l} x\_m = \left|x\right| \\ x\_s = \mathsf{copysign}\left(1, x\right) \\ x\_s \cdot 0 \end{array} \]
x\_m = (fabs.f64 x)
x\_s = (copysign.f64 #s(literal 1 binary64) x)
(FPCore (x_s x_m) :precision binary64 (* x_s 0.0))
x\_m = fabs(x);
x\_s = copysign(1.0, x);
double code(double x_s, double x_m) {
	return x_s * 0.0;
}
x\_m = abs(x)
x\_s = copysign(1.0d0, x)
real(8) function code(x_s, x_m)
    real(8), intent (in) :: x_s
    real(8), intent (in) :: x_m
    code = x_s * 0.0d0
end function
x\_m = Math.abs(x);
x\_s = Math.copySign(1.0, x);
public static double code(double x_s, double x_m) {
	return x_s * 0.0;
}
x\_m = math.fabs(x)
x\_s = math.copysign(1.0, x)
def code(x_s, x_m):
	return x_s * 0.0
x\_m = abs(x)
x\_s = copysign(1.0, x)
function code(x_s, x_m)
	return Float64(x_s * 0.0)
end
x\_m = abs(x);
x\_s = sign(x) * abs(1.0);
function tmp = code(x_s, x_m)
	tmp = x_s * 0.0;
end
x\_m = N[Abs[x], $MachinePrecision]
x\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := N[(x$95$s * 0.0), $MachinePrecision]
\begin{array}{l}
x\_m = \left|x\right|
\\
x\_s = \mathsf{copysign}\left(1, x\right)

\\
x\_s \cdot 0
\end{array}
Derivation
  1. Initial program 73.6%

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

    \[\leadsto \mathsf{\_.f64}\left(\color{blue}{x}, x\right) \]
  4. Step-by-step derivation
    1. Simplified70.0%

      \[\leadsto \color{blue}{x} - x \]
    2. Step-by-step derivation
      1. +-inverses70.0%

        \[\leadsto 0 \]
    3. Applied egg-rr70.0%

      \[\leadsto \color{blue}{0} \]
    4. Add Preprocessing

    Developer Target 1: 99.8% accurate, 0.2× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\left|x\right| < 0.07:\\ \;\;\;\;-\left(\left(\frac{{x}^{3}}{6} - \frac{{x}^{5}}{120}\right) + \frac{{x}^{7}}{5040}\right)\\ \mathbf{else}:\\ \;\;\;\;\sin x - x\\ \end{array} \end{array} \]
    (FPCore (x)
     :precision binary64
     (if (< (fabs x) 0.07)
       (- (+ (- (/ (pow x 3.0) 6.0) (/ (pow x 5.0) 120.0)) (/ (pow x 7.0) 5040.0)))
       (- (sin x) x)))
    double code(double x) {
    	double tmp;
    	if (fabs(x) < 0.07) {
    		tmp = -(((pow(x, 3.0) / 6.0) - (pow(x, 5.0) / 120.0)) + (pow(x, 7.0) / 5040.0));
    	} else {
    		tmp = sin(x) - x;
    	}
    	return tmp;
    }
    
    real(8) function code(x)
        real(8), intent (in) :: x
        real(8) :: tmp
        if (abs(x) < 0.07d0) then
            tmp = -((((x ** 3.0d0) / 6.0d0) - ((x ** 5.0d0) / 120.0d0)) + ((x ** 7.0d0) / 5040.0d0))
        else
            tmp = sin(x) - x
        end if
        code = tmp
    end function
    
    public static double code(double x) {
    	double tmp;
    	if (Math.abs(x) < 0.07) {
    		tmp = -(((Math.pow(x, 3.0) / 6.0) - (Math.pow(x, 5.0) / 120.0)) + (Math.pow(x, 7.0) / 5040.0));
    	} else {
    		tmp = Math.sin(x) - x;
    	}
    	return tmp;
    }
    
    def code(x):
    	tmp = 0
    	if math.fabs(x) < 0.07:
    		tmp = -(((math.pow(x, 3.0) / 6.0) - (math.pow(x, 5.0) / 120.0)) + (math.pow(x, 7.0) / 5040.0))
    	else:
    		tmp = math.sin(x) - x
    	return tmp
    
    function code(x)
    	tmp = 0.0
    	if (abs(x) < 0.07)
    		tmp = Float64(-Float64(Float64(Float64((x ^ 3.0) / 6.0) - Float64((x ^ 5.0) / 120.0)) + Float64((x ^ 7.0) / 5040.0)));
    	else
    		tmp = Float64(sin(x) - x);
    	end
    	return tmp
    end
    
    function tmp_2 = code(x)
    	tmp = 0.0;
    	if (abs(x) < 0.07)
    		tmp = -((((x ^ 3.0) / 6.0) - ((x ^ 5.0) / 120.0)) + ((x ^ 7.0) / 5040.0));
    	else
    		tmp = sin(x) - x;
    	end
    	tmp_2 = tmp;
    end
    
    code[x_] := If[Less[N[Abs[x], $MachinePrecision], 0.07], (-N[(N[(N[(N[Power[x, 3.0], $MachinePrecision] / 6.0), $MachinePrecision] - N[(N[Power[x, 5.0], $MachinePrecision] / 120.0), $MachinePrecision]), $MachinePrecision] + N[(N[Power[x, 7.0], $MachinePrecision] / 5040.0), $MachinePrecision]), $MachinePrecision]), N[(N[Sin[x], $MachinePrecision] - x), $MachinePrecision]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;\left|x\right| < 0.07:\\
    \;\;\;\;-\left(\left(\frac{{x}^{3}}{6} - \frac{{x}^{5}}{120}\right) + \frac{{x}^{7}}{5040}\right)\\
    
    \mathbf{else}:\\
    \;\;\;\;\sin x - x\\
    
    
    \end{array}
    \end{array}
    

    Reproduce

    ?
    herbie shell --seed 2024138 
    (FPCore (x)
      :name "bug500 (missed optimization)"
      :precision binary64
      :pre (and (< -1000.0 x) (< x 1000.0))
    
      :alt
      (! :herbie-platform default (if (< (fabs x) 7/100) (- (+ (- (/ (pow x 3) 6) (/ (pow x 5) 120)) (/ (pow x 7) 5040))) (- (sin x) x)))
    
      (- (sin x) x))