The following tests failed in the JDK18 CI:

jdk/incubator/vector/ShortMaxVectorTests.java
jdk/incubator/vector/Short64VectorTests.java
jdk/incubator/vector/Short512VectorTests.java
jdk/incubator/vector/Short256VectorTests.java
jdk/incubator/vector/Short128VectorTests.java
jdk/incubator/vector/LongMaxVectorTests.java
jdk/incubator/vector/Long512VectorTests.java
jdk/incubator/vector/Long256VectorTests.java
jdk/incubator/vector/IntMaxVectorTests.java
jdk/incubator/vector/Int512VectorTests.java
jdk/incubator/vector/Int256VectorTests.java
jdk/incubator/vector/Int128VectorTests.java

Here's a snippet from the ShortMaxVectorTests.java log file:

test ShortMaxVectorTests.ASHRShortMaxVectorTests(short[-i * 5], short[i * 5]): success
test ShortMaxVectorTests.ASHRShortMaxVectorTests(short[-i * 5], short[i + 1]): success
test ShortMaxVectorTests.ASHRShortMaxVectorTests(short[-i * 5], short[cornerCaseValue(i)]): success
#
# A fatal error has been detected by the Java Runtime Environment:
#
#  EXCEPTION_ACCESS_VIOLATION (0xc0000005) at pc=0x00007ff83675f0ba, pid=7380, tid=45900
#
# JRE version: Java(TM) SE Runtime Environment (18.0+24) (fastdebug build 18-ea+24-1585)
# Java VM: Java HotSpot(TM) 64-Bit Server VM (fastdebug 18-ea+24-1585, compiled mode, sharing, compressed oops, compressed class ptrs, g1 gc, windows-amd64)
# Problematic frame:
# V  [jvm.dll+0xdf0ba]  vrshift_reg_maskedNode::emit+0x16a
#
# Core dump will be written. Default location: T:\\testoutput\\test-support\\jtreg_open_test_jdk_jdk_incubator_vector\\scratch\\0\\hs_err_pid7380.mdmp
#
# An error report file with more information is saved as:
# T:\\testoutput\\test-support\\jtreg_open_test_jdk_jdk_incubator_vector\\scratch\\0\\hs_err_pid7380.log
#
# Compiler replay data is saved as:
# T:\\testoutput\\test-support\\jtreg_open_test_jdk_jdk_incubator_vector\\scratch\\0\\replay_pid7380.log
#
# If you would like to submit a bug report, please visit:
#   https://bugreport.java.com/bugreport/crash.jsp
#
----------System.err:(1/56)----------

Here's the crashing thread's stack:

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

Current thread (0x000001d16e6e2340):  JavaThread "C2 CompilerThread0" daemon [_thread_in_native, id=45900, stack(0x00000082ff700000,0x00000082ff800000)]


Current CompileTask:
C2:  46159 7073    b        ShortMaxVectorTests::ASHRShortMaxVectorTestsMasked (189 bytes)

Stack: [0x00000082ff700000,0x00000082ff800000],  sp=0x00000082ff7faf30,  free space=1003k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
V  [jvm.dll+0xdf0ba]  vrshift_reg_maskedNode::emit+0x16a  (ad_x86.cpp:38221)
V  [jvm.dll+0xbba91b]  PhaseOutput::scratch_emit_size+0x26b  (output.cpp:3348)
V  [jvm.dll+0xbbaeb5]  PhaseOutput::shorten_branches+0x435  (output.cpp:612)
V  [jvm.dll+0xbb4589]  PhaseOutput::Output+0x859  (output.cpp:413)
V  [jvm.dll+0x4e5080]  Compile::Code_Gen+0x380  (compile.cpp:2781)
V  [jvm.dll+0x4e3d8f]  Compile::Compile+0x162f  (compile.cpp:830)
V  [jvm.dll+0x4076b1]  C2Compiler::compile_method+0x131  (c2compiler.cpp:111)
V  [jvm.dll+0x4fcc06]  CompileBroker::invoke_compiler_on_method+0x756  (compileBroker.cpp:2290)
V  [jvm.dll+0x4fa3fd]  CompileBroker::compiler_thread_loop+0x26d  (compileBroker.cpp:1966)
V  [jvm.dll+0xd6b817]  JavaThread::thread_main_inner+0x297  (thread.cpp:1298)
V  [jvm.dll+0xd61174]  Thread::call_run+0x1b4  (thread.cpp:363)
V  [jvm.dll+0xbab26e]  thread_native_entry+0xae  (os_windows.cpp:544)
C  [ucrtbase.dll+0x26b4c]
C  [KERNEL32.DLL+0x14ed0]
C  [ntdll.dll+0x7e39b]


siginfo: EXCEPTION_ACCESS_VIOLATION (0xc0000005), reading address 0x0000000000000000