We can execute one less opcode in every iteration (except for the first) of every for-loop by changing from

 GET_ITER top: FOR_ITER [body] JUMP_BACKWARDS(top) cleanup: end: 

to

 GET_ITER JUMP_FORWARD(bottom) body: [body] bottom: FOR_END(body) cleanup: end: 

This was suggested by @markshannon here, but it appears to be similar in spirit to Loop Inversion.

There seems to be a small (on the order of 1%) benefit, but I imagine the benefit will be magnified after any specialization.