On Tue, 31 Mar 2026 09:08:14 GMT, Christian Hagedorn <[email protected]> wrote:
>> If Valhalla is enabled, we need to load the prototype header on allocations: >> https://github.com/openjdk/valhalla/blob/2c6b468f488147e6851a719e7cd821773c29a8ea/src/hotspot/share/opto/callnode.cpp#L2030-L2032 >> >> This load should be folded, if possible. I enabled the corresponding >> optimization in `LoadNode::Value` and also had to adjust the code in >> `AndLNode::Ideal` to account for the load now being folded. Since this code >> is becoming increasingly complex, I filed >> [JDK-8381388](https://bugs.openjdk.org/browse/JDK-8381388) to simplify it by >> implementing the mark word test as a macro node. >> >> I also removed the unused`ciKlass::prototype_header_offset`. >> >> Thanks, >> Tobias > > src/hotspot/share/opto/mulnode.cpp line 852: > >> 850: } >> 851: >> 852: // Search for GraphKit::mark_word_test patterns and fold the test if >> the result is statically known > > Some comments or graph sketch on the expected patterns would help but to > understand the code better but since we are planning to refactor this > anyways, feel free to do that later. Yes, I agree but decided to not add those for this particular reason. ------------- PR Review Comment: https://git.openjdk.org/valhalla/pull/2281#discussion_r3014611026
