Probably a regression of JDK-8310190.

Only hits the assert in fastdebug, not slowdebug, and product seems unaffected (no failure, results correct).

Reproduce:

java --add-modules java.base --add-exports java.base/jdk.internal.misc=ALL-UNNAMED --add-exports java.base/jdk.internal.util=ALL-UNNAMED -XX:CompileCommand=compileonly,TestMinIntScale::test* -XX:CompileCommand=printcompilation,TestMinIntScale::test* -XX:CompileCommand=TraceAutoVectorization,TestMinIntScale::test*,ALIGN_VECTOR -XX:+TraceNewVectors -Xbatch -XX:LoopUnrollLimit=1000 -XX:+TraceLoopOpts TestMinIntScale.java

# A fatal error has been detected by the Java Runtime Environment:
#
# Internal Error (/oracle-work/jdk-fork2/open/src/hotspot/share/utilities/powerOfTwo.hpp:76), pid=550535, tid=550549
# assert(is_power_of_2(value)) failed: value must be a power of 2: 0xffffffff80000000
#
# JRE version: Java(TM) SE Runtime Environment (23.0) (fastdebug build 23-internal-2024-03-12-0734066.emanuel...)
# Java VM: Java HotSpot(TM) 64-Bit Server VM (fastdebug 23-internal-2024-03-12-0734066.emanuel..., mixed mode, tiered, compressed oops, compressed class ptrs, g1 gc, linux-amd64)
# Problematic frame:
# V [libjvm.so+0x172ebba] SuperWord::adjust_pre_loop_limit_to_align_main_loop_vectors()+0xaba
#
# Core dump will be written. Default location: Core dumps may be processed with "/usr/share/apport/apport -p%p -s%s -c%c -d%d -P%P -u%u -g%g -- %E" (or dumping to /oracle-work/jdk-fork2/build/linux-x64-slowdebug/jdk/bin/core.550535)
#
# An error report file with more information is saved as:
# /oracle-work/jdk-fork2/build/linux-x64-slowdebug/jdk/bin/hs_err_pid550535.log
#
# Compiler replay data is saved as:
# /oracle-work/jdk-fork2/build/linux-x64-slowdebug/jdk/bin/replay_pid550535.log