RFR: Update nmethod caching and clean up unused/duplicate methods [v9]

[Vladimir Kozlov]

On Mon, 16 Jun 2025 13:28:11 GMT, Ashutosh Mehra <asmehra at openjdk.org> wrote:

>> This PR updates nmethod caching to be based on caching of CodeBlob. It also cleans up some dead code and duplicate methods.
>
> Ashutosh Mehra has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Address ADinn's review comment
>   
>   Signed-off-by: Ashutosh Mehra <asmehra at redhat.com>

An other crash happened in aotCode/AOTCodeFlags.java on linux-amd64 in `find_entry()` which looks like during end of test run:

Event: 0.085 Thread 0x00007fc79002f0d0 Before exit entered



#  SIGSEGV (0xb) at pc=0x00007fc79680ead8, pid=3219122, tid=3219333
#
# JRE version: Java(TM) SE Runtime Environment (25.0) (fastdebug build 25-internal-LTS-2025-06-16-1707161.vladimir.kozlov.leyden)
# Java VM: Java HotSpot(TM) 64-Bit Server VM (fastdebug 25-internal-LTS-2025-06-16-1707161.vladimir.kozlov.leyden, mixed mode, sharing, tiered, compressed oops, compressed class ptrs, g1 gc, linux-amd64)
# Problematic frame:
# V  [libjvm.so+0x69cad8]  AOTCodeCache::find_entry(AOTCodeEntry::Kind, unsigned int, unsigned int, unsigned int)+0x158

Command Line: -XX:AOTCache=hello.aot -Xlog:aot -Xlog:aot+codecache* Hello

Host: AMD EPYC 7J13 64-Core Processor, 12 cores, 23G, Oracle Linux Server release 8.10
Time: Mon Jun 16 17:40:14 2025 UTC elapsed time: 0.094271 seconds (0d 0h 0m 0s)

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

Current thread (0x00007fc790249570):  JavaThread "Training replay thread" daemon [_thread_in_vm, id=3219333, stack(0x00007fc7701e6000,0x00007fc7702e6000) (1024K)]

Stack: [0x00007fc7701e6000,0x00007fc7702e6000],  sp=0x00007fc7702e3440,  free space=1013k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
V  [libjvm.so+0x69cad8]  AOTCodeCache::find_entry(AOTCodeEntry::Kind, unsigned int, unsigned int, unsigned int)+0x158  (aotCodeCache.cpp:1001)
V  [libjvm.so+0x69e09f]  AOTCodeCache::find_code_entry(methodHandle const&, unsigned int)+0x22f  (aotCodeCache.cpp:955)
V  [libjvm.so+0xb8cfc3]  CompileBroker::compile_method_base(methodHandle const&, int, int, int, CompileTask::CompileReason, bool, bool, Thread*)+0x103  (compileBroker.cpp:1428)
V  [libjvm.so+0xb8dd68]  CompileBroker::compile_method(methodHandle const&, int, int, int, bool, CompileTask::CompileReason, DirectiveSet*, JavaThread*)+0x4b8  (compileBroker.cpp:1729)
V  [libjvm.so+0xb8e40c]  CompileBroker::compile_method(methodHandle const&, int, int, int, bool, CompileTask::CompileReason, JavaThread*)+0xbc  (compileBroker.cpp:1614)
V  [libjvm.so+0xb4d29c]  CompilationPolicy::maybe_compile_early(methodHandle const&, JavaThread*) [clone .part.0]+0x19c  (compilationPolicy.cpp:120)
V  [libjvm.so+0xb4d78d]  CompilationPolicy::replay_training_at_init_impl(InstanceKlass*, JavaThread*)+0x3ad  (compilationPolicy.cpp:176)
V  [libjvm.so+0xb5244a]  CompilationPolicy::replay_training_at_init_loop(JavaThread*)+0x24a  (compilationPolicy.cpp:214)
V  [libjvm.so+0x110180b]  JavaThread::thread_main_inner()+0x13b  (javaThread.cpp:774)
V  [libjvm.so+0x1b946d6]  Thread::call_run()+0xb6  (thread.cpp:254)
V  [libjvm.so+0x180de89]  thread_native_entry(Thread*)+0x1a9  (os_linux.cpp:868)

-------------

PR Comment: https://git.openjdk.org/leyden/pull/71#issuecomment-2977702830