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eclipse-openj9 / openj9

Eclipse OpenJ9: A Java Virtual Machine for OpenJDK that's optimized for small footprint, fast start-up, and high throughput. Builds on Eclipse OMR (https://github.com/eclipse/omr) and combines with the Extensions for OpenJDK for OpenJ9 repo.
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Investigate functionality of StringBuilderTransformer in Java 9 #139

Open fjeremic opened 7 years ago

fjeremic commented 7 years ago

As noted by @andrewcraik the javac compiler that comes with the Java 9 JDK will generate a method handle sequence for a chained StringBuilder append sequence. We should investigate how the new sequence looks like in Java 9 and what changes are needed to the StringBuilderTransformer [1] optimization to make it functional again.

[1] https://github.com/eclipse/openj9/blob/bb3304d389a16cf96be27cebc160d92eced087d7/runtime/tr.source/trj9/optimizer/StringBuilderTransformer.hpp

dsouzai commented 4 years ago

Does this still need to be open?

fjeremic commented 4 years ago

Does this still need to be open?

I think so. I have no idea what the sequence looks like on JDK11 today. I'm not sure it is feasible to modify the String Builder Transformer in a way to capture the sequence on JDK11. Some investigation needs to be done.