On Wed, 8 Jun 2022 14:44:33 GMT, Jim Laskey <jlas...@openjdk.org> wrote:
>> To take optimal advantage of the pre-existing optimization for repeated >> filters we could split the application of different types of stringifiers. >> >> The resulting difference in order of evaluation is not observable by >> conventional means since all reference type share the same object >> stringifier, and the others are filtering primitives (floats and doubles) >> which have been passed by value already. >> >> This change neutral on many concatenation expression shapes, but for any >> complex expressions with interleaving float/double and reference parameters >> it brings a straightforward reduction in rebinds and underlying LFs >> generated. For example on the >> [MixedStringCombinations.java](https://gist.github.com/cl4es/08fb581dece3a73e89bfa52337bc4248) >> test there's a modest 2% reduction in total classes loaded with this change >> (from 16209 to 15872) > > I make heavy use of the `mh = filterArgument(baseMH, 0, arrayOfFilters);` > pattern. I assumed it generated fewer LF than making individual calls. Am I > wrong? @JimLaskey no, you're generally right to assume that bunching them up reduces the number of LFs created. There's a flaw in the `makeRepeatedFilterForm` transform that means the theoretical total amount of forms can surpass the baseline if you do _both_ one-by-one and all-at-once transforms from the same root MH. That's a very big if, but it's something I've felt slight unease about since I did that optimization. ------------- PR: https://git.openjdk.java.net/jdk/pull/9082
