FastMath dist

Percentage Accurate: 97.8% → 100.0%
Time: 1.3s
Alternatives: 3
Speedup: 1.4×

Specification

?
\[\begin{array}{l} \\ d1 \cdot d2 + d1 \cdot d3 \end{array} \]
(FPCore (d1 d2 d3) :precision binary64 (+ (* d1 d2) (* d1 d3)))
double code(double d1, double d2, double d3) {
	return (d1 * d2) + (d1 * d3);
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(d1, d2, d3)
use fmin_fmax_functions
    real(8), intent (in) :: d1
    real(8), intent (in) :: d2
    real(8), intent (in) :: d3
    code = (d1 * d2) + (d1 * d3)
end function
public static double code(double d1, double d2, double d3) {
	return (d1 * d2) + (d1 * d3);
}
def code(d1, d2, d3):
	return (d1 * d2) + (d1 * d3)
function code(d1, d2, d3)
	return Float64(Float64(d1 * d2) + Float64(d1 * d3))
end
function tmp = code(d1, d2, d3)
	tmp = (d1 * d2) + (d1 * d3);
end
code[d1_, d2_, d3_] := N[(N[(d1 * d2), $MachinePrecision] + N[(d1 * d3), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
d1 \cdot d2 + d1 \cdot d3
\end{array}

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 3 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: 97.8% accurate, 1.0× speedup?

\[\begin{array}{l} \\ d1 \cdot d2 + d1 \cdot d3 \end{array} \]
(FPCore (d1 d2 d3) :precision binary64 (+ (* d1 d2) (* d1 d3)))
double code(double d1, double d2, double d3) {
	return (d1 * d2) + (d1 * d3);
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(d1, d2, d3)
use fmin_fmax_functions
    real(8), intent (in) :: d1
    real(8), intent (in) :: d2
    real(8), intent (in) :: d3
    code = (d1 * d2) + (d1 * d3)
end function
public static double code(double d1, double d2, double d3) {
	return (d1 * d2) + (d1 * d3);
}
def code(d1, d2, d3):
	return (d1 * d2) + (d1 * d3)
function code(d1, d2, d3)
	return Float64(Float64(d1 * d2) + Float64(d1 * d3))
end
function tmp = code(d1, d2, d3)
	tmp = (d1 * d2) + (d1 * d3);
end
code[d1_, d2_, d3_] := N[(N[(d1 * d2), $MachinePrecision] + N[(d1 * d3), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
d1 \cdot d2 + d1 \cdot d3
\end{array}

Alternative 1: 100.0% accurate, 1.4× speedup?

\[\begin{array}{l} \\ \left(d3 + d2\right) \cdot d1 \end{array} \]
(FPCore (d1 d2 d3) :precision binary64 (* (+ d3 d2) d1))
double code(double d1, double d2, double d3) {
	return (d3 + d2) * d1;
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(d1, d2, d3)
use fmin_fmax_functions
    real(8), intent (in) :: d1
    real(8), intent (in) :: d2
    real(8), intent (in) :: d3
    code = (d3 + d2) * d1
end function
public static double code(double d1, double d2, double d3) {
	return (d3 + d2) * d1;
}
def code(d1, d2, d3):
	return (d3 + d2) * d1
function code(d1, d2, d3)
	return Float64(Float64(d3 + d2) * d1)
end
function tmp = code(d1, d2, d3)
	tmp = (d3 + d2) * d1;
end
code[d1_, d2_, d3_] := N[(N[(d3 + d2), $MachinePrecision] * d1), $MachinePrecision]
\begin{array}{l}

\\
\left(d3 + d2\right) \cdot d1
\end{array}
Derivation
  1. Initial program 97.8%

    \[d1 \cdot d2 + d1 \cdot d3 \]
  2. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \color{blue}{d1 \cdot d2} + d1 \cdot d3 \]
    2. lift-*.f64N/A

      \[\leadsto d1 \cdot d2 + \color{blue}{d1 \cdot d3} \]
    3. lift-+.f64N/A

      \[\leadsto \color{blue}{d1 \cdot d2 + d1 \cdot d3} \]
    4. distribute-lft-inN/A

      \[\leadsto \color{blue}{d1 \cdot \left(d2 + d3\right)} \]
    5. *-commutativeN/A

      \[\leadsto \color{blue}{\left(d2 + d3\right) \cdot d1} \]
    6. lower-*.f64N/A

      \[\leadsto \color{blue}{\left(d2 + d3\right) \cdot d1} \]
    7. +-commutativeN/A

      \[\leadsto \color{blue}{\left(d3 + d2\right)} \cdot d1 \]
    8. lower-+.f64100.0

      \[\leadsto \color{blue}{\left(d3 + d2\right)} \cdot d1 \]
  3. Applied rewrites100.0%

    \[\leadsto \color{blue}{\left(d3 + d2\right) \cdot d1} \]
  4. Add Preprocessing

Alternative 2: 54.3% accurate, 0.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;d1 \cdot d2 + d1 \cdot d3 \leq -1 \cdot 10^{-302}:\\ \;\;\;\;d2 \cdot d1\\ \mathbf{else}:\\ \;\;\;\;d3 \cdot d1\\ \end{array} \end{array} \]
(FPCore (d1 d2 d3)
 :precision binary64
 (if (<= (+ (* d1 d2) (* d1 d3)) -1e-302) (* d2 d1) (* d3 d1)))
double code(double d1, double d2, double d3) {
	double tmp;
	if (((d1 * d2) + (d1 * d3)) <= -1e-302) {
		tmp = d2 * d1;
	} else {
		tmp = d3 * d1;
	}
	return tmp;
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(d1, d2, d3)
use fmin_fmax_functions
    real(8), intent (in) :: d1
    real(8), intent (in) :: d2
    real(8), intent (in) :: d3
    real(8) :: tmp
    if (((d1 * d2) + (d1 * d3)) <= (-1d-302)) then
        tmp = d2 * d1
    else
        tmp = d3 * d1
    end if
    code = tmp
end function
public static double code(double d1, double d2, double d3) {
	double tmp;
	if (((d1 * d2) + (d1 * d3)) <= -1e-302) {
		tmp = d2 * d1;
	} else {
		tmp = d3 * d1;
	}
	return tmp;
}
def code(d1, d2, d3):
	tmp = 0
	if ((d1 * d2) + (d1 * d3)) <= -1e-302:
		tmp = d2 * d1
	else:
		tmp = d3 * d1
	return tmp
function code(d1, d2, d3)
	tmp = 0.0
	if (Float64(Float64(d1 * d2) + Float64(d1 * d3)) <= -1e-302)
		tmp = Float64(d2 * d1);
	else
		tmp = Float64(d3 * d1);
	end
	return tmp
end
function tmp_2 = code(d1, d2, d3)
	tmp = 0.0;
	if (((d1 * d2) + (d1 * d3)) <= -1e-302)
		tmp = d2 * d1;
	else
		tmp = d3 * d1;
	end
	tmp_2 = tmp;
end
code[d1_, d2_, d3_] := If[LessEqual[N[(N[(d1 * d2), $MachinePrecision] + N[(d1 * d3), $MachinePrecision]), $MachinePrecision], -1e-302], N[(d2 * d1), $MachinePrecision], N[(d3 * d1), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;d1 \cdot d2 + d1 \cdot d3 \leq -1 \cdot 10^{-302}:\\
\;\;\;\;d2 \cdot d1\\

\mathbf{else}:\\
\;\;\;\;d3 \cdot d1\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (+.f64 (*.f64 d1 d2) (*.f64 d1 d3)) < -9.9999999999999996e-303

    1. Initial program 100.0%

      \[d1 \cdot d2 + d1 \cdot d3 \]
    2. Taylor expanded in d2 around inf

      \[\leadsto \color{blue}{d1 \cdot d2} \]
    3. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto d2 \cdot \color{blue}{d1} \]
      2. lower-*.f6451.8

        \[\leadsto d2 \cdot \color{blue}{d1} \]
    4. Applied rewrites51.8%

      \[\leadsto \color{blue}{d2 \cdot d1} \]

    if -9.9999999999999996e-303 < (+.f64 (*.f64 d1 d2) (*.f64 d1 d3))

    1. Initial program 95.9%

      \[d1 \cdot d2 + d1 \cdot d3 \]
    2. Taylor expanded in d2 around 0

      \[\leadsto \color{blue}{d1 \cdot d3} \]
    3. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto d3 \cdot \color{blue}{d1} \]
      2. lower-*.f6456.4

        \[\leadsto d3 \cdot \color{blue}{d1} \]
    4. Applied rewrites56.4%

      \[\leadsto \color{blue}{d3 \cdot d1} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 3: 53.0% accurate, 2.4× speedup?

\[\begin{array}{l} \\ d2 \cdot d1 \end{array} \]
(FPCore (d1 d2 d3) :precision binary64 (* d2 d1))
double code(double d1, double d2, double d3) {
	return d2 * d1;
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(d1, d2, d3)
use fmin_fmax_functions
    real(8), intent (in) :: d1
    real(8), intent (in) :: d2
    real(8), intent (in) :: d3
    code = d2 * d1
end function
public static double code(double d1, double d2, double d3) {
	return d2 * d1;
}
def code(d1, d2, d3):
	return d2 * d1
function code(d1, d2, d3)
	return Float64(d2 * d1)
end
function tmp = code(d1, d2, d3)
	tmp = d2 * d1;
end
code[d1_, d2_, d3_] := N[(d2 * d1), $MachinePrecision]
\begin{array}{l}

\\
d2 \cdot d1
\end{array}
Derivation
  1. Initial program 97.8%

    \[d1 \cdot d2 + d1 \cdot d3 \]
  2. Taylor expanded in d2 around inf

    \[\leadsto \color{blue}{d1 \cdot d2} \]
  3. Step-by-step derivation
    1. *-commutativeN/A

      \[\leadsto d2 \cdot \color{blue}{d1} \]
    2. lower-*.f6453.0

      \[\leadsto d2 \cdot \color{blue}{d1} \]
  4. Applied rewrites53.0%

    \[\leadsto \color{blue}{d2 \cdot d1} \]
  5. Add Preprocessing

Developer Target 1: 100.0% accurate, 1.4× speedup?

\[\begin{array}{l} \\ d1 \cdot \left(d2 + d3\right) \end{array} \]
(FPCore (d1 d2 d3) :precision binary64 (* d1 (+ d2 d3)))
double code(double d1, double d2, double d3) {
	return d1 * (d2 + d3);
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(d1, d2, d3)
use fmin_fmax_functions
    real(8), intent (in) :: d1
    real(8), intent (in) :: d2
    real(8), intent (in) :: d3
    code = d1 * (d2 + d3)
end function
public static double code(double d1, double d2, double d3) {
	return d1 * (d2 + d3);
}
def code(d1, d2, d3):
	return d1 * (d2 + d3)
function code(d1, d2, d3)
	return Float64(d1 * Float64(d2 + d3))
end
function tmp = code(d1, d2, d3)
	tmp = d1 * (d2 + d3);
end
code[d1_, d2_, d3_] := N[(d1 * N[(d2 + d3), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
d1 \cdot \left(d2 + d3\right)
\end{array}

Reproduce

?
herbie shell --seed 2025112 
(FPCore (d1 d2 d3)
  :name "FastMath dist"
  :precision binary64

  :alt
  (! :herbie-platform c (* d1 (+ d2 d3)))

  (+ (* d1 d2) (* d1 d3)))