If you build the VM with JDK-8058968 included, and run the full suite of Nashorn/Octane with:

~/trunks/jdk9-dev/build/linux-x86_64-normal-server-release/images/j2sdk-image/bin/java -XX:+CITime -jar ~/trunks/jdk9-dev/build/linux-x86_64-normal-server-release/images/j2sdk-image/jre/lib/ext/nashorn.jar -Dnashorn.typeInfo.disabled=false --class-cache-size=0 --persistent-code-cache=false -scripting --log=time test/script/basic/run-octane.js -- --iterations 1

Then you will see this output:
 http://cr.openjdk.java.net/~shade/8058968/new-output-2.txt

Notice how much time Incremental Inlining consumes:

  Total compilation time : 480.712 s
    C2 Compile Time: 376.791 s
         Incremental Inline: 84.199 s
           IdealLoop: 1.061 s
           IGVN: 10.713 s
           Inline: 28.659 s
           Prune Useless: 43.611 s
           Other: 0.155 s

This arguably has an effect on Nashorn warmup, and basically on how fast MH-heavy workloads ramp up.