JDK-8253636 : C2: Adjust NodeClasses::_max_classes
  • Type: Bug
  • Component: hotspot
  • Sub-Component: compiler
  • Affected Version: 15,16
  • Priority: P4
  • Status: Resolved
  • Resolution: Fixed
  • Submitted: 2020-09-25
  • Updated: 2020-10-22
  • Resolved: 2020-10-01
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JDK 16
16 b19Fixed
Related Reports
Relates :  
JDK-8229495 - SIGILL in C2 generated OSR compilation
Description
src/hotspot/share/opto/node.hpp:
...
    DEFINE_CLASS_ID(Halt, Node, 15)
    DEFINE_CLASS_ID(Opaque1, Node, 16)

    _max_classes  = ClassMask_Halt

Opaque1 node class (introduced by JDK-8229495) is beyond _max_classes.
Comments
Tobias Hartmann and I decided not to backport this fix, as it is mainly a code clarity improvement that does not directly affect stability, security or performance.
16-10-2020
I think this should be backported to JDK 15.0.2 since it's a regression.
13-10-2020
Changeset: 5dd9353b Author: Roberto Casta��eda Lozano <roberto.castaneda.lozano@oracle.com> Committer: Tobias Hartmann <thartmann@openjdk.org> Date: 2020-10-01 06:39:25 +0000 URL: https://git.openjdk.java.net/jdk/commit/5dd9353b
01-10-2020
ILW = Incorrect maximum enum value in C2 code, only used by assert which never triggered, no workaround = MLH = P4
28-09-2020