Bug ID: JDK-8287851 C2 crash: assert(t->meet(t0) == t) failed: Not monotonic

Versions (Unresolved/Resolved/Fixed)

The Version table provides details related to the release that this issue/RFE will be addressed.

Unresolved : Release in which this issue/RFE will be addressed.
Resolved: Release in which this issue/RFE has been resolved.
Fixed : Release in which this issue/RFE has been fixed. The release containing this fix may be available for download as an Early Access Release or a General Availability Release.

To download the current JDK release, click here.

JDK 19	JDK 20
19 b30Fixed	20Fixed

Test: java/lang/CompressExpandTest.java🎲

#
# A fatal error has been detected by the Java Runtime Environment:
#
#  Internal Error (/opt/mach5/mesos/work_dir/slaves/779adf21-f3e5-4e6a-a889-8cc0f9bc6fbb-S67136/frameworks/1735e8a2-a1db-478c-8104-60c8b0af87dd-0196/executors/773331be-64c1-481f-954d-74fc36042879/runs/8d35a6c8-425c-411b-a870-816c78e5c42e/workspace/open/src/hotspot/share/opto/phaseX.cpp:1741), pid=13050, tid=13067
#  assert(t->meet(t0) == t) failed: Not monotonic
#
# JRE version: Java(TM) SE Runtime Environment (19.0+26) (fastdebug build 19-ea+26-1963)
# Java VM: Java HotSpot(TM) 64-Bit Server VM (fastdebug 19-ea+26-1963, mixed mode, tiered, compressed oops, compressed class ptrs, g1 gc, linux-amd64)
# Problematic frame:
# V  [libjvm.so+0x17effde]  PhaseCCP::analyze()+0x27e

---------------  T H R E A D  ---------------

Current thread (0x00007fb2fc507f30):  JavaThread "C2 CompilerThread0" daemon [_thread_in_native, id=13067, stack(0x00007fb2e0a9c000,0x00007fb2e0b9d000)]


Current CompileTask:
C2:   5680 1092       4       AbstractCompressExpandTest::testContiguousMasksInt (125 bytes)

Stack: [0x00007fb2e0a9c000,0x00007fb2e0b9d000],  sp=0x00007fb2e0b97f60,  free space=1007k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
V  [libjvm.so+0x17effde]  PhaseCCP::analyze()+0x27e
V  [libjvm.so+0xb01f3f]  Compile::Optimize()+0x96f
V  [libjvm.so+0xb04780]  Compile::Compile(ciEnv*, ciMethod*, int, Options, DirectiveSet*)+0x1520
V  [libjvm.so+0x91b92a]  C2Compiler::compile_method(ciEnv*, ciMethod*, int, bool, DirectiveSet*)+0x62a
V  [libjvm.so+0xb132e8]  CompileBroker::invoke_compiler_on_method(CompileTask*)+0xbb8
V  [libjvm.so+0xb142d8]  CompileBroker::compiler_thread_loop()+0x6f8
V  [libjvm.so+0x1a9de9c]  JavaThread::thread_main_inner()+0x23c
V  [libjvm.so+0x1aa93e0]  Thread::call_run()+0x100
V  [libjvm.so+0x175b574]  thread_native_entry(Thread*)+0x104

Changeset: 1a271645 Author: Jatin Bhateja <jbhateja@openjdk.org> Date: 2022-07-04 11:31:32 +0000 URL: https://git.openjdk.org/jdk19/commit/1a271645a84ac4d7d6570e739d42c05cc328891d
04-07-2022
A pull request was submitted for review. URL: https://git.openjdk.org/jdk19/pull/104 Date: 2022-07-02 18:51:13 +0000
02-07-2022
Thanks for notification; will analyse and update.
10-06-2022
I just filed this JDK-8288194, hits the same assert. Might this be a duplicate? But it only crashes with -XX:TypeProfileLevel=222. and in different test files.
10-06-2022
[~jbhateja] and [~sviswanathan] please look on this. It is regression from recent push and should be fixed for JDK 19.
07-06-2022
[~jbhateja] you might want to fix JDK-8287855 as well with this.
07-06-2022
Looks like a regression in JDK 19, therefore re-targeting to JDK 19.
07-06-2022
ILW = assert in debug build, unknown impact on product builds; intermittent; no workaround = MMH = P3
06-06-2022
[~jbhateja] - Please take a look at this failure. The Tier6 failure occurred in jdk-19+26-1962 which contains the fix for: JDK-8283894 Intrinsify compress and expand bits on x86 and that changeset modified java/lang/CompressExpandTest.java.
06-06-2022

Duplicate :	JDK-8288194 - C2: assert(t->meet(t0) == t) failed: Not monotonic
Duplicate :	JDK-8287855 - Problem in compress_expand_identity
Relates :	JDK-8283894 - Intrinsify compress and expand bits on x86
Relates :	JDK-8279062 - C2: assert(t->meet(t0) == t) failed: Not monotonic after JDK-8278413
Relates :	JDK-8293531 - C2: some vectorapi tests fail assert "Not monotonic" with flag -XX:TypeProfileLevel=222

JDK-8287918 :	ProblemList java/lang/CompressExpandTest.java - Closed
JDK-8287919 :	ProblemList java/lang/CompressExpandTest.java - Resolved