On Fri, 13 Mar 2026 14:55:04 GMT, Tobias Hartmann <[email protected]> wrote:
>> This PR fixes an IR mismatch in `TestLWorld.java` for `test85` and `test86`. >> When merging jdk-26+17, there were some changes to >> `G1BarrierSetC2::estimated_barrier_size` due to >> [JDK-8342382](https://bugs.openjdk.org/browse/JDK-8342382). The barrier size >> is significantly reduced, opening the door to more unrolling as per >> `IdealLoopTree::policy_unroll`. In the specific case of `test85` and >> `test86`, this leads to unrolling where there previously was none and >> splitting a `CountedLoop` into a main and post loop. This breaks the IR >> rules because they rely on exact nodes count. >> >> For `test86`, we can trivially replace `COUNTED_LOOP` by `COUNTED_LOOP_MAIN` >> to avoid counting the loop twice. >> >> For `test85`, we also have a check on `LOAD_UNKNOWN_INLINE`, which ends up >> being appearing four times in the default setup (because of unrolling and >> pre/main/post). This is a bit annoying. It seems the best solution in this >> case is to check the IR right before the pre/main/post, that is at >> `PHASEIDEALLOOP2`. >> >> ### Testing >> - [x] GitHub Actions >> - [x] tier1-4 for this specific test, plus some internal testing >> >> Thank you for reviewing! > > Looks good to me too. Thank you for reviewing @TobiHartmann @chhagedorn! ------------- PR Comment: https://git.openjdk.org/valhalla/pull/2219#issuecomment-4065672627
