Disney BSSRDF, sample scattering profile, upper

Percentage Accurate: 95.9% → 96.2%

Time: 7.9s

Alternatives: 4

Speedup: 1.2×

Specification

\[\left(0 \leq s \land s \leq 256\right) \land \left(0.25 \leq u \land u \leq 1\right)\]

Math

\[\begin{array}{l} \\ \left(3 \cdot s\right) \cdot \log \left(\frac{1}{1 - \frac{u - 0.25}{0.75}}\right) \end{array} \]

FPCore

(FPCore (s u)
 :precision binary32
 (* (* 3.0 s) (log (/ 1.0 (- 1.0 (/ (- u 0.25) 0.75))))))

C

float code(float s, float u) {
	return (3.0f * s) * logf((1.0f / (1.0f - ((u - 0.25f) / 0.75f))));
}

Fortran

real(4) function code(s, u)
    real(4), intent (in) :: s
    real(4), intent (in) :: u
    code = (3.0e0 * s) * log((1.0e0 / (1.0e0 - ((u - 0.25e0) / 0.75e0))))
end function

Julia

function code(s, u)
	return Float32(Float32(Float32(3.0) * s) * log(Float32(Float32(1.0) / Float32(Float32(1.0) - Float32(Float32(u - Float32(0.25)) / Float32(0.75))))))
end

MATLAB

function tmp = code(s, u)
	tmp = (single(3.0) * s) * log((single(1.0) / (single(1.0) - ((u - single(0.25)) / single(0.75)))));
end

Initial Program: 95.9% accurate, 1.0× speedup

Math

\[\begin{array}{l} \\ \left(3 \cdot s\right) \cdot \log \left(\frac{1}{1 - \frac{u - 0.25}{0.75}}\right) \end{array} \]

FPCore

(FPCore (s u)
 :precision binary32
 (* (* 3.0 s) (log (/ 1.0 (- 1.0 (/ (- u 0.25) 0.75))))))

C

float code(float s, float u) {
	return (3.0f * s) * logf((1.0f / (1.0f - ((u - 0.25f) / 0.75f))));
}

Fortran

real(4) function code(s, u)
    real(4), intent (in) :: s
    real(4), intent (in) :: u
    code = (3.0e0 * s) * log((1.0e0 / (1.0e0 - ((u - 0.25e0) / 0.75e0))))
end function

Julia

function code(s, u)
	return Float32(Float32(Float32(3.0) * s) * log(Float32(Float32(1.0) / Float32(Float32(1.0) - Float32(Float32(u - Float32(0.25)) / Float32(0.75))))))
end

MATLAB

function tmp = code(s, u)
	tmp = (single(3.0) * s) * log((single(1.0) / (single(1.0) - ((u - single(0.25)) / single(0.75)))));
end

Alternative 1: 96.2% accurate, 1.2× speedup

Math

\[\begin{array}{l} \\ s \cdot \left(\log \left(1.3333333333333333 - u \cdot 1.3333333333333333\right) \cdot -3\right) \end{array} \]

FPCore

(FPCore (s u)
 :precision binary32
 (* s (* (log (- 1.3333333333333333 (* u 1.3333333333333333))) -3.0)))

C

float code(float s, float u) {
	return s * (logf((1.3333333333333333f - (u * 1.3333333333333333f))) * -3.0f);
}

Fortran

real(4) function code(s, u)
    real(4), intent (in) :: s
    real(4), intent (in) :: u
    code = s * (log((1.3333333333333333e0 - (u * 1.3333333333333333e0))) * (-3.0e0))
end function

Julia

function code(s, u)
	return Float32(s * Float32(log(Float32(Float32(1.3333333333333333) - Float32(u * Float32(1.3333333333333333)))) * Float32(-3.0)))
end

MATLAB

function tmp = code(s, u)
	tmp = s * (log((single(1.3333333333333333) - (u * single(1.3333333333333333)))) * single(-3.0));
end

Derivation

1. Initial program 95.9%

   \[\left(3 \cdot s\right) \cdot \log \left(\frac{1}{1 - \frac{u - 0.25}{0.75}}\right) \]
2. Add Preprocessing
3. Step-by-step derivation

   1. lift-*.f32 N/A

      \[\leadsto \color{blue}{\left(3 \cdot s\right) \cdot \log \left(\frac{1}{1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}}\right)} \]

   2. lift-*.f32 N/A

      \[\leadsto \color{blue}{\left(3 \cdot s\right)} \cdot \log \left(\frac{1}{1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}}\right) \]

   3. associate-*l* N/A

      \[\leadsto \color{blue}{3 \cdot \left(s \cdot \log \left(\frac{1}{1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}}\right)\right)} \]

   4. *-commutative N/A

      \[\leadsto 3 \cdot \color{blue}{\left(\log \left(\frac{1}{1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}}\right) \cdot s\right)} \]

   5. associate-*r* N/A

      \[\leadsto \color{blue}{\left(3 \cdot \log \left(\frac{1}{1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}}\right)\right) \cdot s} \]

   6. lower-*.f32 N/A

      \[\leadsto \color{blue}{\left(3 \cdot \log \left(\frac{1}{1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}}\right)\right) \cdot s} \]

4. Applied rewrites 34.1%

   \[\leadsto \color{blue}{\left(-3 \cdot \mathsf{log1p}\left(-1.3333333333333333 \cdot \left(u - 0.25\right)\right)\right) \cdot s} \]

6. Applied rewrites 9.9%

   \[\leadsto \left(-3 \cdot \color{blue}{\log \left(1 - \mathsf{fma}\left(u, -1.3333333333333333, 0.3333333333333333\right)\right)}\right) \cdot s \]

8. Applied rewrites 96.6%

   \[\leadsto \left(-3 \cdot \log \color{blue}{\left(1.3333333333333333 - 1.3333333333333333 \cdot u\right)}\right) \cdot s \]

9. Final simplification 96.6%

   \[\leadsto s \cdot \left(\log \left(1.3333333333333333 - u \cdot 1.3333333333333333\right) \cdot -3\right) \]
10. Add Preprocessing

Alternative 2: 30.3% accurate, 4.6× speedup

Math

\[\begin{array}{l} \\ \left(\left(\left(\frac{3}{u} + 1.5\right) \cdot s\right) \cdot u\right) \cdot u \end{array} \]

FPCore

(FPCore (s u) :precision binary32 (* (* (* (+ (/ 3.0 u) 1.5) s) u) u))

C

float code(float s, float u) {
	return ((((3.0f / u) + 1.5f) * s) * u) * u;
}

Fortran

real(4) function code(s, u)
    real(4), intent (in) :: s
    real(4), intent (in) :: u
    code = ((((3.0e0 / u) + 1.5e0) * s) * u) * u
end function

Julia

function code(s, u)
	return Float32(Float32(Float32(Float32(Float32(Float32(3.0) / u) + Float32(1.5)) * s) * u) * u)
end

MATLAB

function tmp = code(s, u)
	tmp = ((((single(3.0) / u) + single(1.5)) * s) * u) * u;
end

Derivation

1. Initial program 95.9%

   \[\left(3 \cdot s\right) \cdot \log \left(\frac{1}{1 - \frac{u - 0.25}{0.75}}\right) \]
2. Add Preprocessing

3. Taylor expanded in u around 0

   \[\leadsto \color{blue}{3 \cdot \left(s \cdot \log \frac{3}{4}\right)} \]
4. Step-by-step derivation

   1. *-commutative N/A

      \[\leadsto \color{blue}{\left(s \cdot \log \frac{3}{4}\right) \cdot 3} \]

   2. lower-*.f32 N/A

      \[\leadsto \color{blue}{\left(s \cdot \log \frac{3}{4}\right) \cdot 3} \]

   3. *-commutative N/A

      \[\leadsto \color{blue}{\left(\log \frac{3}{4} \cdot s\right)} \cdot 3 \]

   4. lower-*.f32 N/A

      \[\leadsto \color{blue}{\left(\log \frac{3}{4} \cdot s\right)} \cdot 3 \]

   5. lower-log.f32 7.4

      \[\leadsto \left(\color{blue}{\log 0.75} \cdot s\right) \cdot 3 \]

5. Applied rewrites 7.4%

   \[\leadsto \color{blue}{\left(\log 0.75 \cdot s\right) \cdot 3} \]

6. Taylor expanded in u around 0

   \[\leadsto \color{blue}{3 \cdot \left(s \cdot \log \frac{3}{4}\right) + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right) + 3 \cdot s\right)} \]
7. Step-by-step derivation

   1. +-commutative N/A

      \[\leadsto 3 \cdot \left(s \cdot \log \frac{3}{4}\right) + u \cdot \color{blue}{\left(3 \cdot s + \frac{3}{2} \cdot \left(s \cdot u\right)\right)} \]

   2. distribute-lft-in N/A

      \[\leadsto 3 \cdot \left(s \cdot \log \frac{3}{4}\right) + \color{blue}{\left(u \cdot \left(3 \cdot s\right) + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right)\right)} \]

   3. *-commutative N/A

      \[\leadsto 3 \cdot \left(s \cdot \log \frac{3}{4}\right) + \left(u \cdot \left(3 \cdot s\right) + \color{blue}{\left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u}\right) \]

   4. associate-+r+ N/A

      \[\leadsto \color{blue}{\left(3 \cdot \left(s \cdot \log \frac{3}{4}\right) + u \cdot \left(3 \cdot s\right)\right) + \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u} \]

   5. *-commutative N/A

      \[\leadsto \left(3 \cdot \left(s \cdot \log \frac{3}{4}\right) + \color{blue}{\left(3 \cdot s\right) \cdot u}\right) + \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u \]

   6. associate-*r* N/A

      \[\leadsto \left(3 \cdot \left(s \cdot \log \frac{3}{4}\right) + \color{blue}{3 \cdot \left(s \cdot u\right)}\right) + \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u \]

   7. +-commutative N/A

      \[\leadsto \color{blue}{\left(3 \cdot \left(s \cdot u\right) + 3 \cdot \left(s \cdot \log \frac{3}{4}\right)\right)} + \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u \]

   8. distribute-lft-out N/A

      \[\leadsto \color{blue}{3 \cdot \left(s \cdot u + s \cdot \log \frac{3}{4}\right)} + \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u \]

   9. *-commutative N/A

      \[\leadsto \color{blue}{\left(s \cdot u + s \cdot \log \frac{3}{4}\right) \cdot 3} + \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u \]

   10. distribute-lft-out N/A

       \[\leadsto \color{blue}{\left(s \cdot \left(u + \log \frac{3}{4}\right)\right)} \cdot 3 + \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u \]

   11. associate-*l* N/A

       \[\leadsto \color{blue}{s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right)} + \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u \]

   12. *-commutative N/A

       \[\leadsto s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right) + \color{blue}{\left(\left(s \cdot u\right) \cdot \frac{3}{2}\right)} \cdot u \]

   13. associate-*l* N/A

       \[\leadsto s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right) + \color{blue}{\left(s \cdot u\right) \cdot \left(\frac{3}{2} \cdot u\right)} \]

   14. associate-*l* N/A

       \[\leadsto s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right) + \color{blue}{s \cdot \left(u \cdot \left(\frac{3}{2} \cdot u\right)\right)} \]

   15. distribute-lft-out N/A

       \[\leadsto \color{blue}{s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3 + u \cdot \left(\frac{3}{2} \cdot u\right)\right)} \]

   16. lower-*.f32 N/A

       \[\leadsto \color{blue}{s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3 + u \cdot \left(\frac{3}{2} \cdot u\right)\right)} \]

   17. lower-fma.f32 N/A

       \[\leadsto s \cdot \color{blue}{\mathsf{fma}\left(u + \log \frac{3}{4}, 3, u \cdot \left(\frac{3}{2} \cdot u\right)\right)} \]

8. Applied rewrites 15.0%

   \[\leadsto \color{blue}{s \cdot \mathsf{fma}\left(\log 0.75 + u, 3, \left(u \cdot u\right) \cdot 1.5\right)} \]

9. Taylor expanded in u around inf

   \[\leadsto {u}^{2} \cdot \color{blue}{\left(\frac{3}{2} \cdot s + 3 \cdot \frac{s}{u}\right)} \]
10. Step-by-step derivation

11. Applied rewrites 29.9%

    \[\leadsto \left(\left(s \cdot \left(\frac{3}{u} + 1.5\right)\right) \cdot u\right) \cdot \color{blue}{u} \]

12. Final simplification 29.9%

    \[\leadsto \left(\left(\left(\frac{3}{u} + 1.5\right) \cdot s\right) \cdot u\right) \cdot u \]
13. Add Preprocessing

Alternative 3: 30.3% accurate, 4.6× speedup

Math

\[\begin{array}{l} \\ \left(u \cdot u\right) \cdot \left(\left(\frac{3}{u} + 1.5\right) \cdot s\right) \end{array} \]

FPCore

(FPCore (s u) :precision binary32 (* (* u u) (* (+ (/ 3.0 u) 1.5) s)))

C

float code(float s, float u) {
	return (u * u) * (((3.0f / u) + 1.5f) * s);
}

Fortran

real(4) function code(s, u)
    real(4), intent (in) :: s
    real(4), intent (in) :: u
    code = (u * u) * (((3.0e0 / u) + 1.5e0) * s)
end function

Julia

function code(s, u)
	return Float32(Float32(u * u) * Float32(Float32(Float32(Float32(3.0) / u) + Float32(1.5)) * s))
end

MATLAB

function tmp = code(s, u)
	tmp = (u * u) * (((single(3.0) / u) + single(1.5)) * s);
end

Derivation

1. Initial program 95.9%

   \[\left(3 \cdot s\right) \cdot \log \left(\frac{1}{1 - \frac{u - 0.25}{0.75}}\right) \]
2. Add Preprocessing

3. Taylor expanded in u around 0

   \[\leadsto \color{blue}{3 \cdot \left(s \cdot \log \frac{3}{4}\right)} \]
4. Step-by-step derivation

   1. *-commutative N/A

      \[\leadsto \color{blue}{\left(s \cdot \log \frac{3}{4}\right) \cdot 3} \]

   2. lower-*.f32 N/A

      \[\leadsto \color{blue}{\left(s \cdot \log \frac{3}{4}\right) \cdot 3} \]

   3. *-commutative N/A

      \[\leadsto \color{blue}{\left(\log \frac{3}{4} \cdot s\right)} \cdot 3 \]

   4. lower-*.f32 N/A

      \[\leadsto \color{blue}{\left(\log \frac{3}{4} \cdot s\right)} \cdot 3 \]

   5. lower-log.f32 7.4

      \[\leadsto \left(\color{blue}{\log 0.75} \cdot s\right) \cdot 3 \]

5. Applied rewrites 7.4%

   \[\leadsto \color{blue}{\left(\log 0.75 \cdot s\right) \cdot 3} \]

6. Taylor expanded in u around 0

   \[\leadsto \color{blue}{3 \cdot \left(s \cdot \log \frac{3}{4}\right) + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right) + 3 \cdot s\right)} \]
7. Step-by-step derivation

   1. +-commutative N/A

      \[\leadsto 3 \cdot \left(s \cdot \log \frac{3}{4}\right) + u \cdot \color{blue}{\left(3 \cdot s + \frac{3}{2} \cdot \left(s \cdot u\right)\right)} \]

   2. distribute-lft-in N/A

      \[\leadsto 3 \cdot \left(s \cdot \log \frac{3}{4}\right) + \color{blue}{\left(u \cdot \left(3 \cdot s\right) + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right)\right)} \]

   3. *-commutative N/A

      \[\leadsto 3 \cdot \left(s \cdot \log \frac{3}{4}\right) + \left(u \cdot \left(3 \cdot s\right) + \color{blue}{\left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u}\right) \]

   4. associate-+r+ N/A

      \[\leadsto \color{blue}{\left(3 \cdot \left(s \cdot \log \frac{3}{4}\right) + u \cdot \left(3 \cdot s\right)\right) + \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u} \]

   5. *-commutative N/A

      \[\leadsto \left(3 \cdot \left(s \cdot \log \frac{3}{4}\right) + \color{blue}{\left(3 \cdot s\right) \cdot u}\right) + \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u \]

   6. associate-*r* N/A

      \[\leadsto \left(3 \cdot \left(s \cdot \log \frac{3}{4}\right) + \color{blue}{3 \cdot \left(s \cdot u\right)}\right) + \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u \]

   7. +-commutative N/A

      \[\leadsto \color{blue}{\left(3 \cdot \left(s \cdot u\right) + 3 \cdot \left(s \cdot \log \frac{3}{4}\right)\right)} + \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u \]

   8. distribute-lft-out N/A

      \[\leadsto \color{blue}{3 \cdot \left(s \cdot u + s \cdot \log \frac{3}{4}\right)} + \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u \]

   9. *-commutative N/A

      \[\leadsto \color{blue}{\left(s \cdot u + s \cdot \log \frac{3}{4}\right) \cdot 3} + \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u \]

   10. distribute-lft-out N/A

       \[\leadsto \color{blue}{\left(s \cdot \left(u + \log \frac{3}{4}\right)\right)} \cdot 3 + \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u \]

   11. associate-*l* N/A

       \[\leadsto \color{blue}{s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right)} + \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u \]

   12. *-commutative N/A

       \[\leadsto s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right) + \color{blue}{\left(\left(s \cdot u\right) \cdot \frac{3}{2}\right)} \cdot u \]

   13. associate-*l* N/A

       \[\leadsto s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right) + \color{blue}{\left(s \cdot u\right) \cdot \left(\frac{3}{2} \cdot u\right)} \]

   14. associate-*l* N/A

       \[\leadsto s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right) + \color{blue}{s \cdot \left(u \cdot \left(\frac{3}{2} \cdot u\right)\right)} \]

   15. distribute-lft-out N/A

       \[\leadsto \color{blue}{s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3 + u \cdot \left(\frac{3}{2} \cdot u\right)\right)} \]

   16. lower-*.f32 N/A

       \[\leadsto \color{blue}{s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3 + u \cdot \left(\frac{3}{2} \cdot u\right)\right)} \]

   17. lower-fma.f32 N/A

       \[\leadsto s \cdot \color{blue}{\mathsf{fma}\left(u + \log \frac{3}{4}, 3, u \cdot \left(\frac{3}{2} \cdot u\right)\right)} \]

8. Applied rewrites 14.9%

   \[\leadsto \color{blue}{s \cdot \mathsf{fma}\left(\log 0.75 + u, 3, \left(u \cdot u\right) \cdot 1.5\right)} \]

9. Taylor expanded in u around inf

   \[\leadsto \frac{3}{2} \cdot \color{blue}{\left(s \cdot {u}^{2}\right)} \]
10. Step-by-step derivation

11. Applied rewrites 26.6%

    \[\leadsto \left(\left(u \cdot s\right) \cdot u\right) \cdot \color{blue}{1.5} \]

12. Taylor expanded in u around inf

    \[\leadsto {u}^{2} \cdot \color{blue}{\left(\frac{3}{2} \cdot s + 3 \cdot \frac{s}{u}\right)} \]
13. Step-by-step derivation

14. Applied rewrites 29.9%

    \[\leadsto \left(s \cdot \left(\frac{3}{u} + 1.5\right)\right) \cdot \color{blue}{\left(u \cdot u\right)} \]

15. Final simplification 29.9%

    \[\leadsto \left(u \cdot u\right) \cdot \left(\left(\frac{3}{u} + 1.5\right) \cdot s\right) \]
16. Add Preprocessing

Alternative 4: 29.9% accurate, 12.6× speedup

Math

\[\begin{array}{l} \\ \left(3 \cdot u\right) \cdot s \end{array} \]

FPCore

(FPCore (s u) :precision binary32 (* (* 3.0 u) s))

C

float code(float s, float u) {
	return (3.0f * u) * s;
}

Fortran

real(4) function code(s, u)
    real(4), intent (in) :: s
    real(4), intent (in) :: u
    code = (3.0e0 * u) * s
end function

Julia

function code(s, u)
	return Float32(Float32(Float32(3.0) * u) * s)
end

MATLAB

function tmp = code(s, u)
	tmp = (single(3.0) * u) * s;
end

Derivation

1. Initial program 95.9%

   \[\left(3 \cdot s\right) \cdot \log \left(\frac{1}{1 - \frac{u - 0.25}{0.75}}\right) \]
2. Add Preprocessing

3. Taylor expanded in u around 0

   \[\leadsto \color{blue}{3 \cdot \left(s \cdot \log \frac{3}{4}\right)} \]
4. Step-by-step derivation

   1. *-commutative N/A

      \[\leadsto \color{blue}{\left(s \cdot \log \frac{3}{4}\right) \cdot 3} \]

   2. lower-*.f32 N/A

      \[\leadsto \color{blue}{\left(s \cdot \log \frac{3}{4}\right) \cdot 3} \]

   3. *-commutative N/A

      \[\leadsto \color{blue}{\left(\log \frac{3}{4} \cdot s\right)} \cdot 3 \]

   4. lower-*.f32 N/A

      \[\leadsto \color{blue}{\left(\log \frac{3}{4} \cdot s\right)} \cdot 3 \]

   5. lower-log.f32 7.4

      \[\leadsto \left(\color{blue}{\log 0.75} \cdot s\right) \cdot 3 \]

5. Applied rewrites 7.4%

   \[\leadsto \color{blue}{\left(\log 0.75 \cdot s\right) \cdot 3} \]

6. Taylor expanded in u around 0

   \[\leadsto \color{blue}{3 \cdot \left(s \cdot \log \frac{3}{4}\right) + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right) + 3 \cdot s\right)} \]
7. Step-by-step derivation

   1. +-commutative N/A

      \[\leadsto 3 \cdot \left(s \cdot \log \frac{3}{4}\right) + u \cdot \color{blue}{\left(3 \cdot s + \frac{3}{2} \cdot \left(s \cdot u\right)\right)} \]

   2. distribute-lft-in N/A

      \[\leadsto 3 \cdot \left(s \cdot \log \frac{3}{4}\right) + \color{blue}{\left(u \cdot \left(3 \cdot s\right) + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right)\right)} \]

   3. *-commutative N/A

      \[\leadsto 3 \cdot \left(s \cdot \log \frac{3}{4}\right) + \left(u \cdot \left(3 \cdot s\right) + \color{blue}{\left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u}\right) \]

   4. associate-+r+ N/A

      \[\leadsto \color{blue}{\left(3 \cdot \left(s \cdot \log \frac{3}{4}\right) + u \cdot \left(3 \cdot s\right)\right) + \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u} \]

   5. *-commutative N/A

      \[\leadsto \left(3 \cdot \left(s \cdot \log \frac{3}{4}\right) + \color{blue}{\left(3 \cdot s\right) \cdot u}\right) + \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u \]

   6. associate-*r* N/A

      \[\leadsto \left(3 \cdot \left(s \cdot \log \frac{3}{4}\right) + \color{blue}{3 \cdot \left(s \cdot u\right)}\right) + \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u \]

   7. +-commutative N/A

      \[\leadsto \color{blue}{\left(3 \cdot \left(s \cdot u\right) + 3 \cdot \left(s \cdot \log \frac{3}{4}\right)\right)} + \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u \]

   8. distribute-lft-out N/A

      \[\leadsto \color{blue}{3 \cdot \left(s \cdot u + s \cdot \log \frac{3}{4}\right)} + \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u \]

   9. *-commutative N/A

      \[\leadsto \color{blue}{\left(s \cdot u + s \cdot \log \frac{3}{4}\right) \cdot 3} + \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u \]

   10. distribute-lft-out N/A

       \[\leadsto \color{blue}{\left(s \cdot \left(u + \log \frac{3}{4}\right)\right)} \cdot 3 + \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u \]

   11. associate-*l* N/A

       \[\leadsto \color{blue}{s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right)} + \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u \]

   12. *-commutative N/A

       \[\leadsto s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right) + \color{blue}{\left(\left(s \cdot u\right) \cdot \frac{3}{2}\right)} \cdot u \]

   13. associate-*l* N/A

       \[\leadsto s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right) + \color{blue}{\left(s \cdot u\right) \cdot \left(\frac{3}{2} \cdot u\right)} \]

   14. associate-*l* N/A

       \[\leadsto s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right) + \color{blue}{s \cdot \left(u \cdot \left(\frac{3}{2} \cdot u\right)\right)} \]

   15. distribute-lft-out N/A

       \[\leadsto \color{blue}{s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3 + u \cdot \left(\frac{3}{2} \cdot u\right)\right)} \]

   16. lower-*.f32 N/A

       \[\leadsto \color{blue}{s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3 + u \cdot \left(\frac{3}{2} \cdot u\right)\right)} \]

   17. lower-fma.f32 N/A

       \[\leadsto s \cdot \color{blue}{\mathsf{fma}\left(u + \log \frac{3}{4}, 3, u \cdot \left(\frac{3}{2} \cdot u\right)\right)} \]

8. Applied rewrites 14.9%

   \[\leadsto \color{blue}{s \cdot \mathsf{fma}\left(\log 0.75 + u, 3, \left(u \cdot u\right) \cdot 1.5\right)} \]

9. Taylor expanded in u around 0

   \[\leadsto \color{blue}{3 \cdot \left(s \cdot u\right) + 3 \cdot \left(s \cdot \log \frac{3}{4}\right)} \]
10. Step-by-step derivation

    1. distribute-lft-out N/A

       \[\leadsto \color{blue}{3 \cdot \left(s \cdot u + s \cdot \log \frac{3}{4}\right)} \]

    2. *-commutative N/A

       \[\leadsto \color{blue}{\left(s \cdot u + s \cdot \log \frac{3}{4}\right) \cdot 3} \]

    3. distribute-lft-out N/A

       \[\leadsto \color{blue}{\left(s \cdot \left(u + \log \frac{3}{4}\right)\right)} \cdot 3 \]

    4. associate-*r* N/A

       \[\leadsto \color{blue}{s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right)} \]

    5. *-commutative N/A

       \[\leadsto s \cdot \color{blue}{\left(3 \cdot \left(u + \log \frac{3}{4}\right)\right)} \]

    6. *-commutative N/A

       \[\leadsto \color{blue}{\left(3 \cdot \left(u + \log \frac{3}{4}\right)\right) \cdot s} \]

    7. lower-*.f32 N/A

       \[\leadsto \color{blue}{\left(3 \cdot \left(u + \log \frac{3}{4}\right)\right) \cdot s} \]

    8. *-commutative N/A

       \[\leadsto \color{blue}{\left(\left(u + \log \frac{3}{4}\right) \cdot 3\right)} \cdot s \]

    9. lower-*.f32 N/A

       \[\leadsto \color{blue}{\left(\left(u + \log \frac{3}{4}\right) \cdot 3\right)} \cdot s \]

    10. +-commutative N/A

        \[\leadsto \left(\color{blue}{\left(\log \frac{3}{4} + u\right)} \cdot 3\right) \cdot s \]

    11. lower-+.f32 N/A

        \[\leadsto \left(\color{blue}{\left(\log \frac{3}{4} + u\right)} \cdot 3\right) \cdot s \]

    12. lower-log.f32 26.0

        \[\leadsto \left(\left(\color{blue}{\log 0.75} + u\right) \cdot 3\right) \cdot s \]

11. Applied rewrites 26.0%

    \[\leadsto \color{blue}{\left(\left(\log 0.75 + u\right) \cdot 3\right) \cdot s} \]

12. Taylor expanded in u around inf

    \[\leadsto \left(3 \cdot u\right) \cdot s \]
13. Step-by-step derivation

14. Applied rewrites 29.8%

    \[\leadsto \left(3 \cdot u\right) \cdot s \]
15. Add Preprocessing

Reproduce

herbie shell --seed 2024268 
(FPCore (s u)
  :name "Disney BSSRDF, sample scattering profile, upper"
  :precision binary32
  :pre (and (and (<= 0.0 s) (<= s 256.0)) (and (<= 0.25 u) (<= u 1.0)))
  (* (* 3.0 s) (log (/ 1.0 (- 1.0 (/ (- u 0.25) 0.75))))))