JDK-8331742 : make lightweight locking compiled frames more compact
  • Type: Enhancement
  • Component: hotspot
  • Sub-Component: compiler
  • Affected Version: 23
  • Priority: P3
  • Status: Open
  • Resolution: Unresolved
  • Submitted: 2024-05-06
  • Updated: 2024-07-30
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tbdUnresolved
Related Reports
Relates :  
JDK-8331743 - make lightweight locking interpreter frames more compact
Description
Lightweight locking doesn't appear to use the displaced header slot in the BasicLock stack record of compiled frames.  We should be able to remove it from compiled frames and debug info.
Comments
Here also, the slot is used by c2_MacroAssembler to find the ObjectMonitor for the locked object. https://github.com/openjdk/jdk/pull/20067/files#diff-318d0e76b9a97e8cf8936be1de34e52735c4d947a77cac38babbbf9a081d16fcR835
30-07-2024