The source file src/hotspot/share/jvmci/jvmciCompilerToVM.cpp takes an unreasonable almost 4 minutes to compile on Windows. This needs to be investigated and possibly rewritten in a way that is less taxing on the toolchain, or find some combination of compiler arguments that fixes it. Something is clearly not working as intended and the build environment for anyone developing on Windows is severely impeded.

I was investigating incremental build performance on Windows after some Hotspot engineers started complaining that it had gotten way worse than before. A profile run of the build showed that this compile line took 3:49 on a very fast windows build machine, which is much longer than anything else. (The second slowest was src/hotspot/share/opto/matcher.cpp at 27 sec) I do not know when this happened.