Save a few ALUs

ScriptableRenderPipeline/HDRenderPipeline/HDRP/Material/SubsurfaceScattering/SubsurfaceScattering.compute

 float3 DisneyProfilePolar(float r, float3 S)
 {
 #if 0
-    float3 expOneThird = exp(((-1.0 / 3.0) * r) * S);
+    float3 expOneThird = exp((-1.0 / 3.0) * r * S);
-    float3 p = (k * r) * S;
+    float3 p = (k * S) * r;
     float3 expOneThird = exp2(p);
 #endif
     return expOneThird + expOneThird * expOneThird * expOneThird;