Reliably reproduces like this on current tip:

$ export JAVA_HOME=<point to fastdebug build>
$ export PATH=$JAVA_HOME/bin:$PATH
$ cd test/hotspot/jtreg/testlibrary/ctw
$ make
$ cd dist
$ wget https://repo1.maven.org/maven2/com/sibvisions/jvx/jvxclient/2.6/jvxclient-2.6.jar
$ ./ctw.sh jvxclient-2.6.jar

dist dump
---------------------------------------------
   0 1125 If === 1082 1108 [[ 1135 ]] P=0,900000, C=-1,000000 !orig=1038,389 !jvms: Version::toString @ bci:102 (line 264)
   1 1135 IfFalse === 1125 [[ 920 ]] #0 !orig=[1044],[921],[873],[391],[791],[447] !jvms: Version::toString @ bci:102 (line 264)

# Internal Error (/home/shipilev/shipilev-jdk/src/hotspot/share/opto/compile.cpp:4013), pid=27335, tid=27968
# assert(false) failed: malformed control flow

Current CompileTask:
C2:30638 17695 b 4 com.sibvisions.util.Version::toString (200 bytes)

Stack: [0x00007fad33afb000,0x00007fad33bfc000], sp=0x00007fad33bf72f0, free space=1008k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
V [libjvm.so+0x982919] Compile::final_graph_reshaping()+0x1199 (compile.cpp:4013)
V [libjvm.so+0x983b91] Compile::Optimize()+0x11f1 (compile.cpp:2466)
V [libjvm.so+0x985338] Compile::Compile(ciEnv*, ciMethod*, int, Options, DirectiveSet*)+0x1568 (compile.cpp:854)
V [libjvm.so+0x7f1e05] C2Compiler::compile_method(ciEnv*, ciMethod*, int, bool, DirectiveSet*)+0x1f5 (c2compiler.cpp:130)
V [libjvm.so+0x9904a7] CompileBroker::invoke_compiler_on_method(CompileTask*)+0x477 (compileBroker.cpp:2282)
V [libjvm.so+0x991387] CompileBroker::compiler_thread_loop()+0x307 (compileBroker.cpp:1943)
V [libjvm.so+0xdd2b87] JavaThread::thread_main_inner()+0x1b7 (javaThread.cpp:720)
V [libjvm.so+0x17045df] Thread::call_run()+0x12f (thread.cpp:220)