Where is the android font rendering system located?

Question

Android

One person is compiling for Doogee X5 Pro Android 6 ( link to topic ), everything practically works, but there is one strange bug - rendering of any non-English or Arabic text causes lag (rendering ~ 90% of frames takes more than 40 milliseconds). Replacing the font gave only a slight increase, but the rendering time is still above 20ms. So, according to my assumptions, the font rendering system is to blame. Where is it? Thanks in advance :)