micropython/micropython — pull request #1025 by pfalcon (2014-12-28 05:38:10+00:00)
Title: vm: Record exception ip only for instructions where exceptions may happen.

Mirroring ip to a volatile memory variable for each opcode is an expensive
operation. For quite a lot of often executed opcodes like stack manipulation
or jumps, exceptions cannot actually happen. So, record ip only for opcode
where that's possible.