JDK-8353274 : [PPC64] Bug related to -XX:+UseCompactObjectHeaders -XX:-UseSIGTRAP in JDK-8305895
  • Type: Bug
  • Component: hotspot
  • Sub-Component: compiler
  • Affected Version: 24,25
  • Priority: P3
  • Status: Resolved
  • Resolution: Fixed
  • CPU: ppc
  • Submitted: 2025-03-31
  • Updated: 2025-04-07
  • Resolved: 2025-04-04
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JDK 25
25 masterFixed
Related Reports
Relates :  
JDK-8305895 - Implement JEP 450: Compact Object Headers (Experimental)
Description
In the debug build, we run into the assertion "assert((offset() % end_alignment) == 0) failed: Misaligned verified entry point" when using -XX:+UnlockExperimentalVMOptions -XX:+UseCompactObjectHeaders -XX:-UseSIGTRAP.
Reason is that "MacroAssembler::ic_check" misses "load_narrow_klass_compact" in the slower version which doesn't use SIGTRAP.
Comments
[jdk24u-fix-request] Approval Request from Martin This backport fixes the usage of some flags in combination with JEP 450: Compact Object Headers on PPC64. Some tests are failing without this fix when UseCompactObjectHeaders is enabled. The risk is low. The default behavior (flagless) is not modified. It applies cleanly and only touches PPC64 files.
04-04-2025
A pull request was submitted for review. Branch: master URL: https://git.openjdk.org/jdk24u/pull/178 Date: 2025-04-04 08:08:31 +0000
04-04-2025
Changeset: a13e34da Branch: master Author: Martin Doerr <mdoerr@openjdk.org> Date: 2025-04-04 07:59:41 +0000 URL: https://git.openjdk.org/jdk/commit/a13e34da3f81039b572fd6030d6ee63dfffad612
04-04-2025
A pull request was submitted for review. Branch: master URL: https://git.openjdk.org/jdk/pull/24331 Date: 2025-03-31 14:25:09 +0000
31-03-2025