BoxLockNode size estimation routine does not handle REX2 encoding resulting in the following assertion failure during SPECjvm2008 runs.

#
# A fatal error has been detected by the Java Runtime Environment:
#
# Internal Error (/home/jatinbha/sandboxes/openjdk/jdk/src/hotspot/share/opto/node.hpp:945), pid=369531, tid=386774
# assert(is_Mach()) failed: invalid node class: BoxLock
#
# JRE version: OpenJDK Runtime Environment (25.0) (fastdebug build 25-internal-adhoc.parasa.stockjdk)
# Java VM: OpenJDK 64-Bit Server VM (fastdebug 25-internal-adhoc.parasa.stockjdk, mixed mode, compressed oops, compressed class ptrs, g1 gc, linux-amd64)
# Problematic frame:
# V [libjvm.so+0x162df7e] Node::as_Mach() const [clone .part.0]+0xe
#
# 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 /home/parasa/SPECjvm2008/core.369531)
#
# If you would like to submit a bug report, please visit:
# https://bugreport.java.com/bugreport/crash.jsp
#

--------------- S U M M A R Y ------------

Command Line: -ea -XX:-TieredCompilation -XX:+UnlockExperimentalVMOptions -XX:+UseAPX -XX:-UseBMI2Instructions --add-exports=java.xml/com.sun.org.apache.xerces.internal.parsers=ALL-UNNAMED --add-exports=java.xml/com.sun.org.apache.xerces.internal.util=ALL-UNNAMED /home/parasa/SPECjvm2008/SPECjvm2008.jar -ict -ikv -wt 30 -it 30 -bt 1 scimark.fft.small