Numeric.Log:$cexpm1 from log-domain-0.10.2.1, B

Percentage Accurate: 100.0% → 100.0%
Time: 8.4s
Alternatives: 6
Speedup: 1.2×

Specification

?
\[\begin{array}{l} \\ \left(x \cdot y + x\right) + y \end{array} \]
(FPCore (x y) :precision binary64 (+ (+ (* x y) x) y))
double code(double x, double y) {
	return ((x * y) + x) + y;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    code = ((x * y) + x) + y
end function
public static double code(double x, double y) {
	return ((x * y) + x) + y;
}
def code(x, y):
	return ((x * y) + x) + y
function code(x, y)
	return Float64(Float64(Float64(x * y) + x) + y)
end
function tmp = code(x, y)
	tmp = ((x * y) + x) + y;
end
code[x_, y_] := N[(N[(N[(x * y), $MachinePrecision] + x), $MachinePrecision] + y), $MachinePrecision]
\begin{array}{l}

\\
\left(x \cdot y + x\right) + y
\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: 100.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \left(x \cdot y + x\right) + y \end{array} \]
(FPCore (x y) :precision binary64 (+ (+ (* x y) x) y))
double code(double x, double y) {
	return ((x * y) + x) + y;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    code = ((x * y) + x) + y
end function
public static double code(double x, double y) {
	return ((x * y) + x) + y;
}
def code(x, y):
	return ((x * y) + x) + y
function code(x, y)
	return Float64(Float64(Float64(x * y) + x) + y)
end
function tmp = code(x, y)
	tmp = ((x * y) + x) + y;
end
code[x_, y_] := N[(N[(N[(x * y), $MachinePrecision] + x), $MachinePrecision] + y), $MachinePrecision]
\begin{array}{l}

\\
\left(x \cdot y + x\right) + y
\end{array}

Alternative 1: 100.0% accurate, 1.2× speedup?

\[\begin{array}{l} \\ \mathsf{fma}\left(y + 1, x, y\right) \end{array} \]
(FPCore (x y) :precision binary64 (fma (+ y 1.0) x y))
double code(double x, double y) {
	return fma((y + 1.0), x, y);
}
function code(x, y)
	return fma(Float64(y + 1.0), x, y)
end
code[x_, y_] := N[(N[(y + 1.0), $MachinePrecision] * x + y), $MachinePrecision]
\begin{array}{l}

\\
\mathsf{fma}\left(y + 1, x, y\right)
\end{array}
Derivation
  1. Initial program 100.0%

    \[\left(x \cdot y + x\right) + y \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-+.f64N/A

      \[\leadsto \color{blue}{\left(x \cdot y + x\right) + y} \]
    2. lift-+.f64N/A

      \[\leadsto \color{blue}{\left(x \cdot y + x\right)} + y \]
    3. lift-*.f64N/A

      \[\leadsto \left(\color{blue}{x \cdot y} + x\right) + y \]
    4. *-commutativeN/A

      \[\leadsto \left(\color{blue}{y \cdot x} + x\right) + y \]
    5. distribute-lft1-inN/A

      \[\leadsto \color{blue}{\left(y + 1\right) \cdot x} + y \]
    6. lower-fma.f64N/A

      \[\leadsto \color{blue}{\mathsf{fma}\left(y + 1, x, y\right)} \]
    7. lower-+.f64100.0

      \[\leadsto \mathsf{fma}\left(\color{blue}{y + 1}, x, y\right) \]
  4. Applied rewrites100.0%

    \[\leadsto \color{blue}{\mathsf{fma}\left(y + 1, x, y\right)} \]
  5. Add Preprocessing

Alternative 2: 74.4% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := y + \left(x + y \cdot x\right)\\ \mathbf{if}\;t\_0 \leq -1 \cdot 10^{+54}:\\ \;\;\;\;\mathsf{fma}\left(x, y, x\right)\\ \mathbf{elif}\;t\_0 \leq 2 \cdot 10^{-86}:\\ \;\;\;\;\mathsf{fma}\left(1, x, y\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(x, y, y\right)\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (+ y (+ x (* y x)))))
   (if (<= t_0 -1e+54)
     (fma x y x)
     (if (<= t_0 2e-86) (fma 1.0 x y) (fma x y y)))))
double code(double x, double y) {
	double t_0 = y + (x + (y * x));
	double tmp;
	if (t_0 <= -1e+54) {
		tmp = fma(x, y, x);
	} else if (t_0 <= 2e-86) {
		tmp = fma(1.0, x, y);
	} else {
		tmp = fma(x, y, y);
	}
	return tmp;
}
function code(x, y)
	t_0 = Float64(y + Float64(x + Float64(y * x)))
	tmp = 0.0
	if (t_0 <= -1e+54)
		tmp = fma(x, y, x);
	elseif (t_0 <= 2e-86)
		tmp = fma(1.0, x, y);
	else
		tmp = fma(x, y, y);
	end
	return tmp
end
code[x_, y_] := Block[{t$95$0 = N[(y + N[(x + N[(y * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, -1e+54], N[(x * y + x), $MachinePrecision], If[LessEqual[t$95$0, 2e-86], N[(1.0 * x + y), $MachinePrecision], N[(x * y + y), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := y + \left(x + y \cdot x\right)\\
\mathbf{if}\;t\_0 \leq -1 \cdot 10^{+54}:\\
\;\;\;\;\mathsf{fma}\left(x, y, x\right)\\

\mathbf{elif}\;t\_0 \leq 2 \cdot 10^{-86}:\\
\;\;\;\;\mathsf{fma}\left(1, x, y\right)\\

\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(x, y, y\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (+.f64 (+.f64 (*.f64 x y) x) y) < -1.0000000000000001e54

    1. Initial program 100.0%

      \[\left(x \cdot y + x\right) + y \]
    2. Add Preprocessing
    3. Taylor expanded in x around inf

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

        \[\leadsto x \cdot \color{blue}{\left(y + 1\right)} \]
      2. distribute-lft-inN/A

        \[\leadsto \color{blue}{x \cdot y + x \cdot 1} \]
      3. *-rgt-identityN/A

        \[\leadsto x \cdot y + \color{blue}{x} \]
      4. lower-fma.f6470.4

        \[\leadsto \color{blue}{\mathsf{fma}\left(x, y, x\right)} \]
    5. Applied rewrites70.4%

      \[\leadsto \color{blue}{\mathsf{fma}\left(x, y, x\right)} \]

    if -1.0000000000000001e54 < (+.f64 (+.f64 (*.f64 x y) x) y) < 2.00000000000000017e-86

    1. Initial program 100.0%

      \[\left(x \cdot y + x\right) + y \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. lift-+.f64N/A

        \[\leadsto \color{blue}{\left(x \cdot y + x\right) + y} \]
      2. lift-+.f64N/A

        \[\leadsto \color{blue}{\left(x \cdot y + x\right)} + y \]
      3. lift-*.f64N/A

        \[\leadsto \left(\color{blue}{x \cdot y} + x\right) + y \]
      4. *-commutativeN/A

        \[\leadsto \left(\color{blue}{y \cdot x} + x\right) + y \]
      5. distribute-lft1-inN/A

        \[\leadsto \color{blue}{\left(y + 1\right) \cdot x} + y \]
      6. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(y + 1, x, y\right)} \]
      7. lower-+.f64100.0

        \[\leadsto \mathsf{fma}\left(\color{blue}{y + 1}, x, y\right) \]
    4. Applied rewrites100.0%

      \[\leadsto \color{blue}{\mathsf{fma}\left(y + 1, x, y\right)} \]
    5. Taylor expanded in y around 0

      \[\leadsto \mathsf{fma}\left(\color{blue}{1}, x, y\right) \]
    6. Step-by-step derivation
      1. Applied rewrites100.0%

        \[\leadsto \mathsf{fma}\left(\color{blue}{1}, x, y\right) \]

      if 2.00000000000000017e-86 < (+.f64 (+.f64 (*.f64 x y) x) y)

      1. Initial program 100.0%

        \[\left(x \cdot y + x\right) + y \]
      2. Add Preprocessing
      3. Taylor expanded in y around inf

        \[\leadsto \color{blue}{y \cdot \left(1 + x\right)} \]
      4. Step-by-step derivation
        1. distribute-rgt-inN/A

          \[\leadsto \color{blue}{1 \cdot y + x \cdot y} \]
        2. *-lft-identityN/A

          \[\leadsto \color{blue}{y} + x \cdot y \]
        3. +-commutativeN/A

          \[\leadsto \color{blue}{x \cdot y + y} \]
        4. lower-fma.f6461.9

          \[\leadsto \color{blue}{\mathsf{fma}\left(x, y, y\right)} \]
      5. Applied rewrites61.9%

        \[\leadsto \color{blue}{\mathsf{fma}\left(x, y, y\right)} \]
    7. Recombined 3 regimes into one program.
    8. Final simplification72.9%

      \[\leadsto \begin{array}{l} \mathbf{if}\;y + \left(x + y \cdot x\right) \leq -1 \cdot 10^{+54}:\\ \;\;\;\;\mathsf{fma}\left(x, y, x\right)\\ \mathbf{elif}\;y + \left(x + y \cdot x\right) \leq 2 \cdot 10^{-86}:\\ \;\;\;\;\mathsf{fma}\left(1, x, y\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(x, y, y\right)\\ \end{array} \]
    9. Add Preprocessing

    Alternative 3: 56.8% accurate, 0.3× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} t_0 := y + \left(x + y \cdot x\right)\\ \mathbf{if}\;t\_0 \leq -1 \cdot 10^{-281}:\\ \;\;\;\;\mathsf{fma}\left(x, y, x\right)\\ \mathbf{elif}\;t\_0 \leq 5 \cdot 10^{+301}:\\ \;\;\;\;y \cdot 1\\ \mathbf{else}:\\ \;\;\;\;y \cdot x\\ \end{array} \end{array} \]
    (FPCore (x y)
     :precision binary64
     (let* ((t_0 (+ y (+ x (* y x)))))
       (if (<= t_0 -1e-281) (fma x y x) (if (<= t_0 5e+301) (* y 1.0) (* y x)))))
    double code(double x, double y) {
    	double t_0 = y + (x + (y * x));
    	double tmp;
    	if (t_0 <= -1e-281) {
    		tmp = fma(x, y, x);
    	} else if (t_0 <= 5e+301) {
    		tmp = y * 1.0;
    	} else {
    		tmp = y * x;
    	}
    	return tmp;
    }
    
    function code(x, y)
    	t_0 = Float64(y + Float64(x + Float64(y * x)))
    	tmp = 0.0
    	if (t_0 <= -1e-281)
    		tmp = fma(x, y, x);
    	elseif (t_0 <= 5e+301)
    		tmp = Float64(y * 1.0);
    	else
    		tmp = Float64(y * x);
    	end
    	return tmp
    end
    
    code[x_, y_] := Block[{t$95$0 = N[(y + N[(x + N[(y * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, -1e-281], N[(x * y + x), $MachinePrecision], If[LessEqual[t$95$0, 5e+301], N[(y * 1.0), $MachinePrecision], N[(y * x), $MachinePrecision]]]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    t_0 := y + \left(x + y \cdot x\right)\\
    \mathbf{if}\;t\_0 \leq -1 \cdot 10^{-281}:\\
    \;\;\;\;\mathsf{fma}\left(x, y, x\right)\\
    
    \mathbf{elif}\;t\_0 \leq 5 \cdot 10^{+301}:\\
    \;\;\;\;y \cdot 1\\
    
    \mathbf{else}:\\
    \;\;\;\;y \cdot x\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 3 regimes
    2. if (+.f64 (+.f64 (*.f64 x y) x) y) < -1e-281

      1. Initial program 100.0%

        \[\left(x \cdot y + x\right) + y \]
      2. Add Preprocessing
      3. Taylor expanded in x around inf

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

          \[\leadsto x \cdot \color{blue}{\left(y + 1\right)} \]
        2. distribute-lft-inN/A

          \[\leadsto \color{blue}{x \cdot y + x \cdot 1} \]
        3. *-rgt-identityN/A

          \[\leadsto x \cdot y + \color{blue}{x} \]
        4. lower-fma.f6462.6

          \[\leadsto \color{blue}{\mathsf{fma}\left(x, y, x\right)} \]
      5. Applied rewrites62.6%

        \[\leadsto \color{blue}{\mathsf{fma}\left(x, y, x\right)} \]

      if -1e-281 < (+.f64 (+.f64 (*.f64 x y) x) y) < 5.0000000000000004e301

      1. Initial program 100.0%

        \[\left(x \cdot y + x\right) + y \]
      2. Add Preprocessing
      3. Taylor expanded in y around inf

        \[\leadsto \color{blue}{y \cdot \left(1 + x\right)} \]
      4. Step-by-step derivation
        1. distribute-rgt-inN/A

          \[\leadsto \color{blue}{1 \cdot y + x \cdot y} \]
        2. *-lft-identityN/A

          \[\leadsto \color{blue}{y} + x \cdot y \]
        3. +-commutativeN/A

          \[\leadsto \color{blue}{x \cdot y + y} \]
        4. lower-fma.f6458.0

          \[\leadsto \color{blue}{\mathsf{fma}\left(x, y, y\right)} \]
      5. Applied rewrites58.0%

        \[\leadsto \color{blue}{\mathsf{fma}\left(x, y, y\right)} \]
      6. Step-by-step derivation
        1. Applied rewrites58.0%

          \[\leadsto \left(x + 1\right) \cdot \color{blue}{y} \]
        2. Taylor expanded in x around 0

          \[\leadsto 1 \cdot y \]
        3. Step-by-step derivation
          1. Applied rewrites45.4%

            \[\leadsto 1 \cdot y \]

          if 5.0000000000000004e301 < (+.f64 (+.f64 (*.f64 x y) x) y)

          1. Initial program 100.0%

            \[\left(x \cdot y + x\right) + y \]
          2. Add Preprocessing
          3. Taylor expanded in y around inf

            \[\leadsto \color{blue}{y \cdot \left(1 + x\right)} \]
          4. Step-by-step derivation
            1. distribute-rgt-inN/A

              \[\leadsto \color{blue}{1 \cdot y + x \cdot y} \]
            2. *-lft-identityN/A

              \[\leadsto \color{blue}{y} + x \cdot y \]
            3. +-commutativeN/A

              \[\leadsto \color{blue}{x \cdot y + y} \]
            4. lower-fma.f64100.0

              \[\leadsto \color{blue}{\mathsf{fma}\left(x, y, y\right)} \]
          5. Applied rewrites100.0%

            \[\leadsto \color{blue}{\mathsf{fma}\left(x, y, y\right)} \]
          6. Taylor expanded in x around inf

            \[\leadsto x \cdot \color{blue}{y} \]
          7. Step-by-step derivation
            1. Applied rewrites100.0%

              \[\leadsto y \cdot \color{blue}{x} \]
          8. Recombined 3 regimes into one program.
          9. Final simplification56.7%

            \[\leadsto \begin{array}{l} \mathbf{if}\;y + \left(x + y \cdot x\right) \leq -1 \cdot 10^{-281}:\\ \;\;\;\;\mathsf{fma}\left(x, y, x\right)\\ \mathbf{elif}\;y + \left(x + y \cdot x\right) \leq 5 \cdot 10^{+301}:\\ \;\;\;\;y \cdot 1\\ \mathbf{else}:\\ \;\;\;\;y \cdot x\\ \end{array} \]
          10. Add Preprocessing

          Alternative 4: 63.2% accurate, 0.5× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y + \left(x + y \cdot x\right) \leq -1 \cdot 10^{-281}:\\ \;\;\;\;\mathsf{fma}\left(x, y, x\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(x, y, y\right)\\ \end{array} \end{array} \]
          (FPCore (x y)
           :precision binary64
           (if (<= (+ y (+ x (* y x))) -1e-281) (fma x y x) (fma x y y)))
          double code(double x, double y) {
          	double tmp;
          	if ((y + (x + (y * x))) <= -1e-281) {
          		tmp = fma(x, y, x);
          	} else {
          		tmp = fma(x, y, y);
          	}
          	return tmp;
          }
          
          function code(x, y)
          	tmp = 0.0
          	if (Float64(y + Float64(x + Float64(y * x))) <= -1e-281)
          		tmp = fma(x, y, x);
          	else
          		tmp = fma(x, y, y);
          	end
          	return tmp
          end
          
          code[x_, y_] := If[LessEqual[N[(y + N[(x + N[(y * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], -1e-281], N[(x * y + x), $MachinePrecision], N[(x * y + y), $MachinePrecision]]
          
          \begin{array}{l}
          
          \\
          \begin{array}{l}
          \mathbf{if}\;y + \left(x + y \cdot x\right) \leq -1 \cdot 10^{-281}:\\
          \;\;\;\;\mathsf{fma}\left(x, y, x\right)\\
          
          \mathbf{else}:\\
          \;\;\;\;\mathsf{fma}\left(x, y, y\right)\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 2 regimes
          2. if (+.f64 (+.f64 (*.f64 x y) x) y) < -1e-281

            1. Initial program 100.0%

              \[\left(x \cdot y + x\right) + y \]
            2. Add Preprocessing
            3. Taylor expanded in x around inf

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

                \[\leadsto x \cdot \color{blue}{\left(y + 1\right)} \]
              2. distribute-lft-inN/A

                \[\leadsto \color{blue}{x \cdot y + x \cdot 1} \]
              3. *-rgt-identityN/A

                \[\leadsto x \cdot y + \color{blue}{x} \]
              4. lower-fma.f6462.6

                \[\leadsto \color{blue}{\mathsf{fma}\left(x, y, x\right)} \]
            5. Applied rewrites62.6%

              \[\leadsto \color{blue}{\mathsf{fma}\left(x, y, x\right)} \]

            if -1e-281 < (+.f64 (+.f64 (*.f64 x y) x) y)

            1. Initial program 100.0%

              \[\left(x \cdot y + x\right) + y \]
            2. Add Preprocessing
            3. Taylor expanded in y around inf

              \[\leadsto \color{blue}{y \cdot \left(1 + x\right)} \]
            4. Step-by-step derivation
              1. distribute-rgt-inN/A

                \[\leadsto \color{blue}{1 \cdot y + x \cdot y} \]
              2. *-lft-identityN/A

                \[\leadsto \color{blue}{y} + x \cdot y \]
              3. +-commutativeN/A

                \[\leadsto \color{blue}{x \cdot y + y} \]
              4. lower-fma.f6461.5

                \[\leadsto \color{blue}{\mathsf{fma}\left(x, y, y\right)} \]
            5. Applied rewrites61.5%

              \[\leadsto \color{blue}{\mathsf{fma}\left(x, y, y\right)} \]
          3. Recombined 2 regimes into one program.
          4. Final simplification62.1%

            \[\leadsto \begin{array}{l} \mathbf{if}\;y + \left(x + y \cdot x\right) \leq -1 \cdot 10^{-281}:\\ \;\;\;\;\mathsf{fma}\left(x, y, x\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(x, y, y\right)\\ \end{array} \]
          5. Add Preprocessing

          Alternative 5: 62.2% accurate, 0.7× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -3950000:\\ \;\;\;\;y \cdot x\\ \mathbf{elif}\;x \leq 1:\\ \;\;\;\;y \cdot 1\\ \mathbf{else}:\\ \;\;\;\;y \cdot x\\ \end{array} \end{array} \]
          (FPCore (x y)
           :precision binary64
           (if (<= x -3950000.0) (* y x) (if (<= x 1.0) (* y 1.0) (* y x))))
          double code(double x, double y) {
          	double tmp;
          	if (x <= -3950000.0) {
          		tmp = y * x;
          	} else if (x <= 1.0) {
          		tmp = y * 1.0;
          	} else {
          		tmp = y * x;
          	}
          	return tmp;
          }
          
          real(8) function code(x, y)
              real(8), intent (in) :: x
              real(8), intent (in) :: y
              real(8) :: tmp
              if (x <= (-3950000.0d0)) then
                  tmp = y * x
              else if (x <= 1.0d0) then
                  tmp = y * 1.0d0
              else
                  tmp = y * x
              end if
              code = tmp
          end function
          
          public static double code(double x, double y) {
          	double tmp;
          	if (x <= -3950000.0) {
          		tmp = y * x;
          	} else if (x <= 1.0) {
          		tmp = y * 1.0;
          	} else {
          		tmp = y * x;
          	}
          	return tmp;
          }
          
          def code(x, y):
          	tmp = 0
          	if x <= -3950000.0:
          		tmp = y * x
          	elif x <= 1.0:
          		tmp = y * 1.0
          	else:
          		tmp = y * x
          	return tmp
          
          function code(x, y)
          	tmp = 0.0
          	if (x <= -3950000.0)
          		tmp = Float64(y * x);
          	elseif (x <= 1.0)
          		tmp = Float64(y * 1.0);
          	else
          		tmp = Float64(y * x);
          	end
          	return tmp
          end
          
          function tmp_2 = code(x, y)
          	tmp = 0.0;
          	if (x <= -3950000.0)
          		tmp = y * x;
          	elseif (x <= 1.0)
          		tmp = y * 1.0;
          	else
          		tmp = y * x;
          	end
          	tmp_2 = tmp;
          end
          
          code[x_, y_] := If[LessEqual[x, -3950000.0], N[(y * x), $MachinePrecision], If[LessEqual[x, 1.0], N[(y * 1.0), $MachinePrecision], N[(y * x), $MachinePrecision]]]
          
          \begin{array}{l}
          
          \\
          \begin{array}{l}
          \mathbf{if}\;x \leq -3950000:\\
          \;\;\;\;y \cdot x\\
          
          \mathbf{elif}\;x \leq 1:\\
          \;\;\;\;y \cdot 1\\
          
          \mathbf{else}:\\
          \;\;\;\;y \cdot x\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 2 regimes
          2. if x < -3.95e6 or 1 < x

            1. Initial program 100.0%

              \[\left(x \cdot y + x\right) + y \]
            2. Add Preprocessing
            3. Taylor expanded in y around inf

              \[\leadsto \color{blue}{y \cdot \left(1 + x\right)} \]
            4. Step-by-step derivation
              1. distribute-rgt-inN/A

                \[\leadsto \color{blue}{1 \cdot y + x \cdot y} \]
              2. *-lft-identityN/A

                \[\leadsto \color{blue}{y} + x \cdot y \]
              3. +-commutativeN/A

                \[\leadsto \color{blue}{x \cdot y + y} \]
              4. lower-fma.f6453.2

                \[\leadsto \color{blue}{\mathsf{fma}\left(x, y, y\right)} \]
            5. Applied rewrites53.2%

              \[\leadsto \color{blue}{\mathsf{fma}\left(x, y, y\right)} \]
            6. Taylor expanded in x around inf

              \[\leadsto x \cdot \color{blue}{y} \]
            7. Step-by-step derivation
              1. Applied rewrites52.5%

                \[\leadsto y \cdot \color{blue}{x} \]

              if -3.95e6 < x < 1

              1. Initial program 100.0%

                \[\left(x \cdot y + x\right) + y \]
              2. Add Preprocessing
              3. Taylor expanded in y around inf

                \[\leadsto \color{blue}{y \cdot \left(1 + x\right)} \]
              4. Step-by-step derivation
                1. distribute-rgt-inN/A

                  \[\leadsto \color{blue}{1 \cdot y + x \cdot y} \]
                2. *-lft-identityN/A

                  \[\leadsto \color{blue}{y} + x \cdot y \]
                3. +-commutativeN/A

                  \[\leadsto \color{blue}{x \cdot y + y} \]
                4. lower-fma.f6478.4

                  \[\leadsto \color{blue}{\mathsf{fma}\left(x, y, y\right)} \]
              5. Applied rewrites78.4%

                \[\leadsto \color{blue}{\mathsf{fma}\left(x, y, y\right)} \]
              6. Step-by-step derivation
                1. Applied rewrites78.3%

                  \[\leadsto \left(x + 1\right) \cdot \color{blue}{y} \]
                2. Taylor expanded in x around 0

                  \[\leadsto 1 \cdot y \]
                3. Step-by-step derivation
                  1. Applied rewrites77.0%

                    \[\leadsto 1 \cdot y \]
                4. Recombined 2 regimes into one program.
                5. Final simplification64.6%

                  \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -3950000:\\ \;\;\;\;y \cdot x\\ \mathbf{elif}\;x \leq 1:\\ \;\;\;\;y \cdot 1\\ \mathbf{else}:\\ \;\;\;\;y \cdot x\\ \end{array} \]
                6. Add Preprocessing

                Alternative 6: 27.1% accurate, 2.0× speedup?

                \[\begin{array}{l} \\ y \cdot x \end{array} \]
                (FPCore (x y) :precision binary64 (* y x))
                double code(double x, double y) {
                	return y * x;
                }
                
                real(8) function code(x, y)
                    real(8), intent (in) :: x
                    real(8), intent (in) :: y
                    code = y * x
                end function
                
                public static double code(double x, double y) {
                	return y * x;
                }
                
                def code(x, y):
                	return y * x
                
                function code(x, y)
                	return Float64(y * x)
                end
                
                function tmp = code(x, y)
                	tmp = y * x;
                end
                
                code[x_, y_] := N[(y * x), $MachinePrecision]
                
                \begin{array}{l}
                
                \\
                y \cdot x
                \end{array}
                
                Derivation
                1. Initial program 100.0%

                  \[\left(x \cdot y + x\right) + y \]
                2. Add Preprocessing
                3. Taylor expanded in y around inf

                  \[\leadsto \color{blue}{y \cdot \left(1 + x\right)} \]
                4. Step-by-step derivation
                  1. distribute-rgt-inN/A

                    \[\leadsto \color{blue}{1 \cdot y + x \cdot y} \]
                  2. *-lft-identityN/A

                    \[\leadsto \color{blue}{y} + x \cdot y \]
                  3. +-commutativeN/A

                    \[\leadsto \color{blue}{x \cdot y + y} \]
                  4. lower-fma.f6465.6

                    \[\leadsto \color{blue}{\mathsf{fma}\left(x, y, y\right)} \]
                5. Applied rewrites65.6%

                  \[\leadsto \color{blue}{\mathsf{fma}\left(x, y, y\right)} \]
                6. Taylor expanded in x around inf

                  \[\leadsto x \cdot \color{blue}{y} \]
                7. Step-by-step derivation
                  1. Applied rewrites28.5%

                    \[\leadsto y \cdot \color{blue}{x} \]
                  2. Add Preprocessing

                  Reproduce

                  ?
                  herbie shell --seed 2024232 
                  (FPCore (x y)
                    :name "Numeric.Log:$cexpm1 from log-domain-0.10.2.1, B"
                    :precision binary64
                    (+ (+ (* x y) x) y))