C2: assert(vlen_in_bytes == 64) failed: 2

The attached Java Fuzzer test starts to fail after JDK-8286972:

To reproduce:
$ java -Xcomp -XX:CompileOnly=Test Test.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-S66914/frameworks/1735e8a2-a1db-478c-8104-60c8b0af87dd-0196/executors/f438564a-997a-4f93-8215-28dc0c0bef6d/runs/f41da18c-9f23-49a7-ab67-ad61fa19003a/workspace/open/src/hotspot/cpu/x86/c2_MacroAssembler_x86.cpp:1513), pid=18922, tid=18935
# assert(vlen_in_bytes == 64) failed: 2
#
# JRE version: Java(TM) SE Runtime Environment (19.0+24) (fastdebug build 19-ea+24-1832)
# Java VM: Java HotSpot(TM) 64-Bit Server VM (fastdebug 19-ea+24-1832, compiled mode, sharing, tiered, compressed oops, compressed class ptrs, g1 gc, linux-amd64)
# Problematic frame:
# V [libjvm.so+0x8bb323] C2_MacroAssembler::load_iota_indices(XMMRegisterImpl*, RegisterImpl*, int)+0xa3
.........
Command Line: -Xmx1G -Xcomp -Xbatch -XX:CompileOnly=Test -XX:CompileCommand=quiet Test
.........
Current CompileTask:
C2: 308 8 b 4 Test::mainTest (688 bytes)

Stack: [0x00007ffa31002000,0x00007ffa31103000], sp=0x00007ffa310fd8f0, free space=1006k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
V [libjvm.so+0x8bb323] C2_MacroAssembler::load_iota_indices(XMMRegisterImpl*, RegisterImpl*, int)+0xa3
V [libjvm.so+0x454eee] VectorPopulateIndexNode::emit(CodeBuffer&, PhaseRegAlloc*) const+0x21e
V [libjvm.so+0x172b8e2] PhaseOutput::scratch_emit_size(Node const*)+0x452
V [libjvm.so+0x1721f98] PhaseOutput::shorten_branches(unsigned int*)+0x2d8
V [libjvm.so+0x173481a] PhaseOutput::Output()+0xcfa
V [libjvm.so+0xabe79b] Compile::Code_Gen()+0x42b
V [libjvm.so+0xac4009] Compile::Compile(ciEnv*, ciMethod*, int, Options, DirectiveSet*)+0x15f9
V [libjvm.so+0x8dadda] C2Compiler::compile_method(ciEnv*, ciMethod*, int, bool, DirectiveSet*)+0x62a
V [libjvm.so+0xad2a08] CompileBroker::invoke_compiler_on_method(CompileTask*)+0xb98
V [libjvm.so+0xad39c8] CompileBroker::compiler_thread_loop()+0x6c8
V [libjvm.so+0x1a4a47a] JavaThread::thread_main_inner()+0x21a
V [libjvm.so+0x1a57d30] Thread::call_run()+0x100
V [libjvm.so+0x170a244] thread_native_entry(Thread*)+0x104