[PATCH] Change list assignment commonality detection to use the optree, fixing commonality detection with &&

Change the common variable detection for list assignment to use the
op tree structure instead of the linkedlist.
Fixes detection of commonality detection with conditional operator like &&
Also splits processing of the lhs and the rhs, such that using the
same variable twice in the rhs does not cause commonality to be
detected.

Gerard Goossen

• [PATCH] Change list assignment commonality detection to use the optree, fixing commonality detection with && by Gerard Goossen