Adding comments
Using ranged for loop and thus cleaning up code
Check if variable has been eliminated once updated to replaced var

While updating dominators, we didn't check if the parent is still a real
var, or has been removed (and memory-elimed). Also, cleaning up code
by using ranged loop and removing code copy-paste
This is memmove since it can be copying to itself
Adding comments
Using ranged for loop and thus cleaning up code
Check if variable has been eliminated once updated to replaced var

While updating dominators, we didn't check if the parent is still a real
var, or has been removed (and memory-elimed). Also, cleaning up code
by using ranged loop and removing code copy-paste
This is memmove since it can be copying to itself
Merge branch 'master' into testing