JDK-8298301 : C2: assert(main_cmp->in(2)->Opcode() == Op_Opaque1) failed: main loop has no opaque node?
  • Type: Bug
  • Component: hotspot
  • Sub-Component: compiler
  • Affected Version: 20
  • Priority: P2
  • Status: Resolved
  • Resolution: Fixed
  • Submitted: 2022-12-07
  • Updated: 2022-12-12
  • Resolved: 2022-12-07
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JDK 20
20 b27Fixed
Related Reports
Relates :  
JDK-8269820 - C2 PhaseIdealLoop::do_unroll get wrong opaque node
Description
Starts to fail after JDK-8269820.

Reproduce:
Run compiler/c2/TestFoldCompares.java with -XX:+UseParallelGC

#
# A fatal error has been detected by the Java Runtime Environment:
#
#  Internal Error (/home/christian/jdk/open/src/hotspot/share/opto/loopTransform.cpp:3581), pid=806142, tid=806151
#  assert(main_cmp->in(2)->Opcode() == Op_Opaque1) failed: main loop has no opaque node?
#
# JRE version: Java(TM) SE Runtime Environment (20.0) (slowdebug build 20-internal-2022-12-07-1633265.christian...)
# Java VM: Java HotSpot(TM) 64-Bit Server VM (slowdebug 20-internal-2022-12-07-1633265.christian..., mixed mode, tiered, compressed oops, compressed class ptrs, parallel gc, linux-amd64)
# Problematic frame:
# V  [libjvm.so+0xf569ca]  IdealLoopTree::remove_main_post_loops(CountedLoopNode*, PhaseIdealLoop*)+0x1ea
Comments
The fix for this bug is integrated in jdk-20+27-2181.
07-12-2022
Changeset: e86f31b5 Author: Christian Hagedorn <chagedorn@openjdk.org> Date: 2022-12-07 18:32:28 +0000 URL: https://git.openjdk.org/jdk/commit/e86f31b5e71af00fea9cd989a86c1e75e3df1821
07-12-2022
A pull request was submitted for review. URL: https://git.openjdk.org/jdk/pull/11567 Date: 2022-12-07 17:03:08 +0000
07-12-2022
ILW = C2 assertion when removing a main loop, various tests, disable compilation of affected method = HMM = P2
07-12-2022