note range != 0 compiler optimizations

Author: TheIronBorn

src/distributions/uniform.rs

@@ -568,9 +568,8 @@ macro_rules! uniform_simd_int_impl {
                         // wrapping addition
                         let result = self.low + hi;
                         // `select` here compiles to a blend operation
-                        // TODO: look into how the compiler manages the
-                        // constant case. Are the compare and blend operations
-                        // avoided?
+                        // When `range.eq(0).none()` the compare and blend
+                        // operations are avoided.
                         let v: $ty = v.cast();
                         return range.gt($unsigned::splat(0)).select(result, v);
                     }