Changing Android Dalvik Compiler

I need to change the Android 4.3 Dalvik compiler which is located here (https://android.googlesource.com/platform/dalvik/+/android-4.3.1_r1/) to do the following: When the compiler compiles any Android app, I need the compiler to insert code before and after any [login to view URL]() found in any app to measure the elapsed execution time of the [login to view URL]() and print the result. When any app contains [login to view URL]() runs, it will measure and print the elapsed time although the programmers did not add any code to the app to measure and print the elapsed execution time because the code to do that was inserted by the compiler.