Codec.Picture.Jpg.FastDct:referenceDct from JuicyPixels-3.2.6.1

Percentage Accurate: 27.3% → 30.0%
Time: 15.2s
Alternatives: 2
Speedup: 44.8×

Specification

?
\[\begin{array}{l} \\ \left(x \cdot \cos \left(\frac{\left(\left(y \cdot 2 + 1\right) \cdot z\right) \cdot t}{16}\right)\right) \cdot \cos \left(\frac{\left(\left(a \cdot 2 + 1\right) \cdot b\right) \cdot t}{16}\right) \end{array} \]
(FPCore (x y z t a b)
 :precision binary64
 (*
  (* x (cos (/ (* (* (+ (* y 2.0) 1.0) z) t) 16.0)))
  (cos (/ (* (* (+ (* a 2.0) 1.0) b) t) 16.0))))
double code(double x, double y, double z, double t, double a, double b) {
	return (x * cos((((((y * 2.0) + 1.0) * z) * t) / 16.0))) * cos((((((a * 2.0) + 1.0) * b) * t) / 16.0));
}
real(8) function code(x, y, z, t, a, b)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    code = (x * cos((((((y * 2.0d0) + 1.0d0) * z) * t) / 16.0d0))) * cos((((((a * 2.0d0) + 1.0d0) * b) * t) / 16.0d0))
end function
public static double code(double x, double y, double z, double t, double a, double b) {
	return (x * Math.cos((((((y * 2.0) + 1.0) * z) * t) / 16.0))) * Math.cos((((((a * 2.0) + 1.0) * b) * t) / 16.0));
}
def code(x, y, z, t, a, b):
	return (x * math.cos((((((y * 2.0) + 1.0) * z) * t) / 16.0))) * math.cos((((((a * 2.0) + 1.0) * b) * t) / 16.0))
function code(x, y, z, t, a, b)
	return Float64(Float64(x * cos(Float64(Float64(Float64(Float64(Float64(y * 2.0) + 1.0) * z) * t) / 16.0))) * cos(Float64(Float64(Float64(Float64(Float64(a * 2.0) + 1.0) * b) * t) / 16.0)))
end
function tmp = code(x, y, z, t, a, b)
	tmp = (x * cos((((((y * 2.0) + 1.0) * z) * t) / 16.0))) * cos((((((a * 2.0) + 1.0) * b) * t) / 16.0));
end
code[x_, y_, z_, t_, a_, b_] := N[(N[(x * N[Cos[N[(N[(N[(N[(N[(y * 2.0), $MachinePrecision] + 1.0), $MachinePrecision] * z), $MachinePrecision] * t), $MachinePrecision] / 16.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * N[Cos[N[(N[(N[(N[(N[(a * 2.0), $MachinePrecision] + 1.0), $MachinePrecision] * b), $MachinePrecision] * t), $MachinePrecision] / 16.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(x \cdot \cos \left(\frac{\left(\left(y \cdot 2 + 1\right) \cdot z\right) \cdot t}{16}\right)\right) \cdot \cos \left(\frac{\left(\left(a \cdot 2 + 1\right) \cdot b\right) \cdot t}{16}\right)
\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 2 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: 27.3% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \left(x \cdot \cos \left(\frac{\left(\left(y \cdot 2 + 1\right) \cdot z\right) \cdot t}{16}\right)\right) \cdot \cos \left(\frac{\left(\left(a \cdot 2 + 1\right) \cdot b\right) \cdot t}{16}\right) \end{array} \]
(FPCore (x y z t a b)
 :precision binary64
 (*
  (* x (cos (/ (* (* (+ (* y 2.0) 1.0) z) t) 16.0)))
  (cos (/ (* (* (+ (* a 2.0) 1.0) b) t) 16.0))))
double code(double x, double y, double z, double t, double a, double b) {
	return (x * cos((((((y * 2.0) + 1.0) * z) * t) / 16.0))) * cos((((((a * 2.0) + 1.0) * b) * t) / 16.0));
}
real(8) function code(x, y, z, t, a, b)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    code = (x * cos((((((y * 2.0d0) + 1.0d0) * z) * t) / 16.0d0))) * cos((((((a * 2.0d0) + 1.0d0) * b) * t) / 16.0d0))
end function
public static double code(double x, double y, double z, double t, double a, double b) {
	return (x * Math.cos((((((y * 2.0) + 1.0) * z) * t) / 16.0))) * Math.cos((((((a * 2.0) + 1.0) * b) * t) / 16.0));
}
def code(x, y, z, t, a, b):
	return (x * math.cos((((((y * 2.0) + 1.0) * z) * t) / 16.0))) * math.cos((((((a * 2.0) + 1.0) * b) * t) / 16.0))
function code(x, y, z, t, a, b)
	return Float64(Float64(x * cos(Float64(Float64(Float64(Float64(Float64(y * 2.0) + 1.0) * z) * t) / 16.0))) * cos(Float64(Float64(Float64(Float64(Float64(a * 2.0) + 1.0) * b) * t) / 16.0)))
end
function tmp = code(x, y, z, t, a, b)
	tmp = (x * cos((((((y * 2.0) + 1.0) * z) * t) / 16.0))) * cos((((((a * 2.0) + 1.0) * b) * t) / 16.0));
end
code[x_, y_, z_, t_, a_, b_] := N[(N[(x * N[Cos[N[(N[(N[(N[(N[(y * 2.0), $MachinePrecision] + 1.0), $MachinePrecision] * z), $MachinePrecision] * t), $MachinePrecision] / 16.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * N[Cos[N[(N[(N[(N[(N[(a * 2.0), $MachinePrecision] + 1.0), $MachinePrecision] * b), $MachinePrecision] * t), $MachinePrecision] / 16.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(x \cdot \cos \left(\frac{\left(\left(y \cdot 2 + 1\right) \cdot z\right) \cdot t}{16}\right)\right) \cdot \cos \left(\frac{\left(\left(a \cdot 2 + 1\right) \cdot b\right) \cdot t}{16}\right)
\end{array}

Alternative 1: 30.0% accurate, 1.7× speedup?

\[\begin{array}{l} \\ \left(x \cdot 1\right) \cdot \cos \left(\frac{\frac{1}{\mathsf{fma}\left(a, a \cdot 4, -1\right)}}{\frac{16}{b}} \cdot \left(-t\right)\right) \end{array} \]
(FPCore (x y z t a b)
 :precision binary64
 (* (* x 1.0) (cos (* (/ (/ 1.0 (fma a (* a 4.0) -1.0)) (/ 16.0 b)) (- t)))))
double code(double x, double y, double z, double t, double a, double b) {
	return (x * 1.0) * cos((((1.0 / fma(a, (a * 4.0), -1.0)) / (16.0 / b)) * -t));
}
function code(x, y, z, t, a, b)
	return Float64(Float64(x * 1.0) * cos(Float64(Float64(Float64(1.0 / fma(a, Float64(a * 4.0), -1.0)) / Float64(16.0 / b)) * Float64(-t))))
end
code[x_, y_, z_, t_, a_, b_] := N[(N[(x * 1.0), $MachinePrecision] * N[Cos[N[(N[(N[(1.0 / N[(a * N[(a * 4.0), $MachinePrecision] + -1.0), $MachinePrecision]), $MachinePrecision] / N[(16.0 / b), $MachinePrecision]), $MachinePrecision] * (-t)), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(x \cdot 1\right) \cdot \cos \left(\frac{\frac{1}{\mathsf{fma}\left(a, a \cdot 4, -1\right)}}{\frac{16}{b}} \cdot \left(-t\right)\right)
\end{array}
Derivation
  1. Initial program 28.8%

    \[\left(x \cdot \cos \left(\frac{\left(\left(y \cdot 2 + 1\right) \cdot z\right) \cdot t}{16}\right)\right) \cdot \cos \left(\frac{\left(\left(a \cdot 2 + 1\right) \cdot b\right) \cdot t}{16}\right) \]
  2. Add Preprocessing
  3. Taylor expanded in z around 0

    \[\leadsto \left(x \cdot \color{blue}{1}\right) \cdot \cos \left(\frac{\left(\left(a \cdot 2 + 1\right) \cdot b\right) \cdot t}{16}\right) \]
  4. Step-by-step derivation
    1. Applied rewrites30.5%

      \[\leadsto \left(x \cdot \color{blue}{1}\right) \cdot \cos \left(\frac{\left(\left(a \cdot 2 + 1\right) \cdot b\right) \cdot t}{16}\right) \]
    2. Applied rewrites25.8%

      \[\leadsto \left(x \cdot 1\right) \cdot \cos \color{blue}{\left(\frac{\frac{1}{\mathsf{fma}\left(a, a \cdot 4, -1\right)}}{\frac{16}{b}} \cdot \frac{\mathsf{fma}\left(2, a, 1\right)}{\frac{1}{\mathsf{fma}\left(a, a \cdot 4, -1\right) \cdot \left(t \cdot 1\right)}}\right)} \]
    3. Taylor expanded in a around 0

      \[\leadsto \left(x \cdot 1\right) \cdot \cos \left(\frac{\frac{1}{\mathsf{fma}\left(a, a \cdot 4, -1\right)}}{\frac{16}{b}} \cdot \color{blue}{\left(-1 \cdot t\right)}\right) \]
    4. Step-by-step derivation
      1. mul-1-negN/A

        \[\leadsto \left(x \cdot 1\right) \cdot \cos \left(\frac{\frac{1}{\mathsf{fma}\left(a, a \cdot 4, -1\right)}}{\frac{16}{b}} \cdot \color{blue}{\left(\mathsf{neg}\left(t\right)\right)}\right) \]
      2. lower-neg.f6433.0

        \[\leadsto \left(x \cdot 1\right) \cdot \cos \left(\frac{\frac{1}{\mathsf{fma}\left(a, a \cdot 4, -1\right)}}{\frac{16}{b}} \cdot \color{blue}{\left(-t\right)}\right) \]
    5. Applied rewrites33.0%

      \[\leadsto \left(x \cdot 1\right) \cdot \cos \left(\frac{\frac{1}{\mathsf{fma}\left(a, a \cdot 4, -1\right)}}{\frac{16}{b}} \cdot \color{blue}{\left(-t\right)}\right) \]
    6. Add Preprocessing

    Alternative 2: 30.4% accurate, 44.8× speedup?

    \[\begin{array}{l} \\ x \cdot 1 \end{array} \]
    (FPCore (x y z t a b) :precision binary64 (* x 1.0))
    double code(double x, double y, double z, double t, double a, double b) {
    	return x * 1.0;
    }
    
    real(8) function code(x, y, z, t, a, b)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        real(8), intent (in) :: z
        real(8), intent (in) :: t
        real(8), intent (in) :: a
        real(8), intent (in) :: b
        code = x * 1.0d0
    end function
    
    public static double code(double x, double y, double z, double t, double a, double b) {
    	return x * 1.0;
    }
    
    def code(x, y, z, t, a, b):
    	return x * 1.0
    
    function code(x, y, z, t, a, b)
    	return Float64(x * 1.0)
    end
    
    function tmp = code(x, y, z, t, a, b)
    	tmp = x * 1.0;
    end
    
    code[x_, y_, z_, t_, a_, b_] := N[(x * 1.0), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    x \cdot 1
    \end{array}
    
    Derivation
    1. Initial program 28.8%

      \[\left(x \cdot \cos \left(\frac{\left(\left(y \cdot 2 + 1\right) \cdot z\right) \cdot t}{16}\right)\right) \cdot \cos \left(\frac{\left(\left(a \cdot 2 + 1\right) \cdot b\right) \cdot t}{16}\right) \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. lift-/.f64N/A

        \[\leadsto \left(x \cdot \cos \left(\frac{\left(\left(y \cdot 2 + 1\right) \cdot z\right) \cdot t}{16}\right)\right) \cdot \cos \color{blue}{\left(\frac{\left(\left(a \cdot 2 + 1\right) \cdot b\right) \cdot t}{16}\right)} \]
      2. lift-*.f64N/A

        \[\leadsto \left(x \cdot \cos \left(\frac{\left(\left(y \cdot 2 + 1\right) \cdot z\right) \cdot t}{16}\right)\right) \cdot \cos \left(\frac{\color{blue}{\left(\left(a \cdot 2 + 1\right) \cdot b\right) \cdot t}}{16}\right) \]
      3. associate-/l*N/A

        \[\leadsto \left(x \cdot \cos \left(\frac{\left(\left(y \cdot 2 + 1\right) \cdot z\right) \cdot t}{16}\right)\right) \cdot \cos \color{blue}{\left(\left(\left(a \cdot 2 + 1\right) \cdot b\right) \cdot \frac{t}{16}\right)} \]
      4. clear-numN/A

        \[\leadsto \left(x \cdot \cos \left(\frac{\left(\left(y \cdot 2 + 1\right) \cdot z\right) \cdot t}{16}\right)\right) \cdot \cos \left(\left(\left(a \cdot 2 + 1\right) \cdot b\right) \cdot \color{blue}{\frac{1}{\frac{16}{t}}}\right) \]
      5. un-div-invN/A

        \[\leadsto \left(x \cdot \cos \left(\frac{\left(\left(y \cdot 2 + 1\right) \cdot z\right) \cdot t}{16}\right)\right) \cdot \cos \color{blue}{\left(\frac{\left(a \cdot 2 + 1\right) \cdot b}{\frac{16}{t}}\right)} \]
      6. lower-/.f64N/A

        \[\leadsto \left(x \cdot \cos \left(\frac{\left(\left(y \cdot 2 + 1\right) \cdot z\right) \cdot t}{16}\right)\right) \cdot \cos \color{blue}{\left(\frac{\left(a \cdot 2 + 1\right) \cdot b}{\frac{16}{t}}\right)} \]
      7. lift-*.f64N/A

        \[\leadsto \left(x \cdot \cos \left(\frac{\left(\left(y \cdot 2 + 1\right) \cdot z\right) \cdot t}{16}\right)\right) \cdot \cos \left(\frac{\color{blue}{\left(a \cdot 2 + 1\right) \cdot b}}{\frac{16}{t}}\right) \]
      8. *-commutativeN/A

        \[\leadsto \left(x \cdot \cos \left(\frac{\left(\left(y \cdot 2 + 1\right) \cdot z\right) \cdot t}{16}\right)\right) \cdot \cos \left(\frac{\color{blue}{b \cdot \left(a \cdot 2 + 1\right)}}{\frac{16}{t}}\right) \]
      9. lift-+.f64N/A

        \[\leadsto \left(x \cdot \cos \left(\frac{\left(\left(y \cdot 2 + 1\right) \cdot z\right) \cdot t}{16}\right)\right) \cdot \cos \left(\frac{b \cdot \color{blue}{\left(a \cdot 2 + 1\right)}}{\frac{16}{t}}\right) \]
      10. distribute-rgt-inN/A

        \[\leadsto \left(x \cdot \cos \left(\frac{\left(\left(y \cdot 2 + 1\right) \cdot z\right) \cdot t}{16}\right)\right) \cdot \cos \left(\frac{\color{blue}{\left(a \cdot 2\right) \cdot b + 1 \cdot b}}{\frac{16}{t}}\right) \]
      11. *-lft-identityN/A

        \[\leadsto \left(x \cdot \cos \left(\frac{\left(\left(y \cdot 2 + 1\right) \cdot z\right) \cdot t}{16}\right)\right) \cdot \cos \left(\frac{\left(a \cdot 2\right) \cdot b + \color{blue}{b}}{\frac{16}{t}}\right) \]
      12. lower-fma.f64N/A

        \[\leadsto \left(x \cdot \cos \left(\frac{\left(\left(y \cdot 2 + 1\right) \cdot z\right) \cdot t}{16}\right)\right) \cdot \cos \left(\frac{\color{blue}{\mathsf{fma}\left(a \cdot 2, b, b\right)}}{\frac{16}{t}}\right) \]
      13. lift-*.f64N/A

        \[\leadsto \left(x \cdot \cos \left(\frac{\left(\left(y \cdot 2 + 1\right) \cdot z\right) \cdot t}{16}\right)\right) \cdot \cos \left(\frac{\mathsf{fma}\left(\color{blue}{a \cdot 2}, b, b\right)}{\frac{16}{t}}\right) \]
      14. *-commutativeN/A

        \[\leadsto \left(x \cdot \cos \left(\frac{\left(\left(y \cdot 2 + 1\right) \cdot z\right) \cdot t}{16}\right)\right) \cdot \cos \left(\frac{\mathsf{fma}\left(\color{blue}{2 \cdot a}, b, b\right)}{\frac{16}{t}}\right) \]
      15. lower-*.f64N/A

        \[\leadsto \left(x \cdot \cos \left(\frac{\left(\left(y \cdot 2 + 1\right) \cdot z\right) \cdot t}{16}\right)\right) \cdot \cos \left(\frac{\mathsf{fma}\left(\color{blue}{2 \cdot a}, b, b\right)}{\frac{16}{t}}\right) \]
      16. lower-/.f6428.8

        \[\leadsto \left(x \cdot \cos \left(\frac{\left(\left(y \cdot 2 + 1\right) \cdot z\right) \cdot t}{16}\right)\right) \cdot \cos \left(\frac{\mathsf{fma}\left(2 \cdot a, b, b\right)}{\color{blue}{\frac{16}{t}}}\right) \]
    4. Applied rewrites28.8%

      \[\leadsto \left(x \cdot \cos \left(\frac{\left(\left(y \cdot 2 + 1\right) \cdot z\right) \cdot t}{16}\right)\right) \cdot \cos \color{blue}{\left(\frac{\mathsf{fma}\left(2 \cdot a, b, b\right)}{\frac{16}{t}}\right)} \]
    5. Taylor expanded in a around 0

      \[\leadsto \color{blue}{x \cdot \left(\cos \left(\frac{1}{16} \cdot \left(b \cdot t\right)\right) \cdot \cos \left(\frac{1}{16} \cdot \left(t \cdot \left(z \cdot \left(1 + 2 \cdot y\right)\right)\right)\right)\right)} \]
    6. Step-by-step derivation
      1. lower-*.f64N/A

        \[\leadsto \color{blue}{x \cdot \left(\cos \left(\frac{1}{16} \cdot \left(b \cdot t\right)\right) \cdot \cos \left(\frac{1}{16} \cdot \left(t \cdot \left(z \cdot \left(1 + 2 \cdot y\right)\right)\right)\right)\right)} \]
      2. *-commutativeN/A

        \[\leadsto x \cdot \color{blue}{\left(\cos \left(\frac{1}{16} \cdot \left(t \cdot \left(z \cdot \left(1 + 2 \cdot y\right)\right)\right)\right) \cdot \cos \left(\frac{1}{16} \cdot \left(b \cdot t\right)\right)\right)} \]
      3. lower-*.f64N/A

        \[\leadsto x \cdot \color{blue}{\left(\cos \left(\frac{1}{16} \cdot \left(t \cdot \left(z \cdot \left(1 + 2 \cdot y\right)\right)\right)\right) \cdot \cos \left(\frac{1}{16} \cdot \left(b \cdot t\right)\right)\right)} \]
      4. lower-cos.f64N/A

        \[\leadsto x \cdot \left(\color{blue}{\cos \left(\frac{1}{16} \cdot \left(t \cdot \left(z \cdot \left(1 + 2 \cdot y\right)\right)\right)\right)} \cdot \cos \left(\frac{1}{16} \cdot \left(b \cdot t\right)\right)\right) \]
      5. lower-*.f64N/A

        \[\leadsto x \cdot \left(\cos \color{blue}{\left(\frac{1}{16} \cdot \left(t \cdot \left(z \cdot \left(1 + 2 \cdot y\right)\right)\right)\right)} \cdot \cos \left(\frac{1}{16} \cdot \left(b \cdot t\right)\right)\right) \]
      6. lower-*.f64N/A

        \[\leadsto x \cdot \left(\cos \left(\frac{1}{16} \cdot \color{blue}{\left(t \cdot \left(z \cdot \left(1 + 2 \cdot y\right)\right)\right)}\right) \cdot \cos \left(\frac{1}{16} \cdot \left(b \cdot t\right)\right)\right) \]
      7. +-commutativeN/A

        \[\leadsto x \cdot \left(\cos \left(\frac{1}{16} \cdot \left(t \cdot \left(z \cdot \color{blue}{\left(2 \cdot y + 1\right)}\right)\right)\right) \cdot \cos \left(\frac{1}{16} \cdot \left(b \cdot t\right)\right)\right) \]
      8. distribute-lft-inN/A

        \[\leadsto x \cdot \left(\cos \left(\frac{1}{16} \cdot \left(t \cdot \color{blue}{\left(z \cdot \left(2 \cdot y\right) + z \cdot 1\right)}\right)\right) \cdot \cos \left(\frac{1}{16} \cdot \left(b \cdot t\right)\right)\right) \]
      9. *-rgt-identityN/A

        \[\leadsto x \cdot \left(\cos \left(\frac{1}{16} \cdot \left(t \cdot \left(z \cdot \left(2 \cdot y\right) + \color{blue}{z}\right)\right)\right) \cdot \cos \left(\frac{1}{16} \cdot \left(b \cdot t\right)\right)\right) \]
      10. lower-fma.f64N/A

        \[\leadsto x \cdot \left(\cos \left(\frac{1}{16} \cdot \left(t \cdot \color{blue}{\mathsf{fma}\left(z, 2 \cdot y, z\right)}\right)\right) \cdot \cos \left(\frac{1}{16} \cdot \left(b \cdot t\right)\right)\right) \]
      11. *-commutativeN/A

        \[\leadsto x \cdot \left(\cos \left(\frac{1}{16} \cdot \left(t \cdot \mathsf{fma}\left(z, \color{blue}{y \cdot 2}, z\right)\right)\right) \cdot \cos \left(\frac{1}{16} \cdot \left(b \cdot t\right)\right)\right) \]
      12. lower-*.f64N/A

        \[\leadsto x \cdot \left(\cos \left(\frac{1}{16} \cdot \left(t \cdot \mathsf{fma}\left(z, \color{blue}{y \cdot 2}, z\right)\right)\right) \cdot \cos \left(\frac{1}{16} \cdot \left(b \cdot t\right)\right)\right) \]
      13. lower-cos.f64N/A

        \[\leadsto x \cdot \left(\cos \left(\frac{1}{16} \cdot \left(t \cdot \mathsf{fma}\left(z, y \cdot 2, z\right)\right)\right) \cdot \color{blue}{\cos \left(\frac{1}{16} \cdot \left(b \cdot t\right)\right)}\right) \]
      14. lower-*.f64N/A

        \[\leadsto x \cdot \left(\cos \left(\frac{1}{16} \cdot \left(t \cdot \mathsf{fma}\left(z, y \cdot 2, z\right)\right)\right) \cdot \cos \color{blue}{\left(\frac{1}{16} \cdot \left(b \cdot t\right)\right)}\right) \]
      15. *-commutativeN/A

        \[\leadsto x \cdot \left(\cos \left(\frac{1}{16} \cdot \left(t \cdot \mathsf{fma}\left(z, y \cdot 2, z\right)\right)\right) \cdot \cos \left(\frac{1}{16} \cdot \color{blue}{\left(t \cdot b\right)}\right)\right) \]
      16. lower-*.f6430.3

        \[\leadsto x \cdot \left(\cos \left(0.0625 \cdot \left(t \cdot \mathsf{fma}\left(z, y \cdot 2, z\right)\right)\right) \cdot \cos \left(0.0625 \cdot \color{blue}{\left(t \cdot b\right)}\right)\right) \]
    7. Applied rewrites30.3%

      \[\leadsto \color{blue}{x \cdot \left(\cos \left(0.0625 \cdot \left(t \cdot \mathsf{fma}\left(z, y \cdot 2, z\right)\right)\right) \cdot \cos \left(0.0625 \cdot \left(t \cdot b\right)\right)\right)} \]
    8. Taylor expanded in t around 0

      \[\leadsto x \cdot 1 \]
    9. Step-by-step derivation
      1. Applied rewrites32.7%

        \[\leadsto x \cdot 1 \]
      2. Add Preprocessing

      Developer Target 1: 30.0% accurate, 1.1× speedup?

      \[\begin{array}{l} \\ x \cdot \cos \left(\frac{b}{16} \cdot \frac{t}{\left(1 - a \cdot 2\right) + {\left(a \cdot 2\right)}^{2}}\right) \end{array} \]
      (FPCore (x y z t a b)
       :precision binary64
       (* x (cos (* (/ b 16.0) (/ t (+ (- 1.0 (* a 2.0)) (pow (* a 2.0) 2.0)))))))
      double code(double x, double y, double z, double t, double a, double b) {
      	return x * cos(((b / 16.0) * (t / ((1.0 - (a * 2.0)) + pow((a * 2.0), 2.0)))));
      }
      
      real(8) function code(x, y, z, t, a, b)
          real(8), intent (in) :: x
          real(8), intent (in) :: y
          real(8), intent (in) :: z
          real(8), intent (in) :: t
          real(8), intent (in) :: a
          real(8), intent (in) :: b
          code = x * cos(((b / 16.0d0) * (t / ((1.0d0 - (a * 2.0d0)) + ((a * 2.0d0) ** 2.0d0)))))
      end function
      
      public static double code(double x, double y, double z, double t, double a, double b) {
      	return x * Math.cos(((b / 16.0) * (t / ((1.0 - (a * 2.0)) + Math.pow((a * 2.0), 2.0)))));
      }
      
      def code(x, y, z, t, a, b):
      	return x * math.cos(((b / 16.0) * (t / ((1.0 - (a * 2.0)) + math.pow((a * 2.0), 2.0)))))
      
      function code(x, y, z, t, a, b)
      	return Float64(x * cos(Float64(Float64(b / 16.0) * Float64(t / Float64(Float64(1.0 - Float64(a * 2.0)) + (Float64(a * 2.0) ^ 2.0))))))
      end
      
      function tmp = code(x, y, z, t, a, b)
      	tmp = x * cos(((b / 16.0) * (t / ((1.0 - (a * 2.0)) + ((a * 2.0) ^ 2.0)))));
      end
      
      code[x_, y_, z_, t_, a_, b_] := N[(x * N[Cos[N[(N[(b / 16.0), $MachinePrecision] * N[(t / N[(N[(1.0 - N[(a * 2.0), $MachinePrecision]), $MachinePrecision] + N[Power[N[(a * 2.0), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      x \cdot \cos \left(\frac{b}{16} \cdot \frac{t}{\left(1 - a \cdot 2\right) + {\left(a \cdot 2\right)}^{2}}\right)
      \end{array}
      

      Reproduce

      ?
      herbie shell --seed 2024221 
      (FPCore (x y z t a b)
        :name "Codec.Picture.Jpg.FastDct:referenceDct from JuicyPixels-3.2.6.1"
        :precision binary64
      
        :alt
        (! :herbie-platform default (* x (cos (* (/ b 16) (/ t (+ (- 1 (* a 2)) (pow (* a 2) 2)))))))
      
        (* (* x (cos (/ (* (* (+ (* y 2.0) 1.0) z) t) 16.0))) (cos (/ (* (* (+ (* a 2.0) 1.0) b) t) 16.0))))