the dex bytecode is interpreted by the Dalvik VM. Sometimes, this DEX code is just in time compiled to machine code instructions. To know what these are, you will have to hook the JIT infrastructure by modifying dalvik. With the introduction of ART, dex is compiled ahead of time into machine instructions.
There is no off the shelf mechanism to obtain power consumption. you may have to use other tools.
This got nothing to do with the kernel. Dalvik modifications belong in the android-platform group.