JDK-8235143 : C2: No memory state needed in Thread::currentThread() intrinsic
  • Type: Enhancement
  • Component: hotspot
  • Sub-Component: compiler
  • Affected Version: 8,11,14
  • Priority: P3
  • Status: Resolved
  • Resolution: Fixed
  • Submitted: 2019-11-29
  • Updated: 2020-09-29
  • Resolved: 2019-12-09
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JDK 14
14 b27Fixed
Related Reports
Relates :  
JDK-8224996 - Investigate memory access C2 optimizations
Description
Thread::currentThread() intrinsic doesn't need memory state, since current thread can't be changed during method activation.   

It helps with optimising thread checks by forcing all thread checks to share a single value representing current thread.

(The optimisation should be revisited in Project Loom, since it may be affected by how continuations are implemented.)
Comments
URL: https://hg.openjdk.java.net/jdk/jdk/rev/c3203a6a2ed4 User: vlivanov Date: 2019-12-09 17:05:55 +0000
09-12-2019