The concepts discussed in this section can also be applied to eliminate partially dead code. A definition of a variable is partial ly dead if the variable is live on some paths and not others.
We can optimize the program execution by only performing the definition along paths where the variable is live. Unlike partial-redundancy elimination, where expressions are moved before the original, the new definitions are placed after the original.
Develop an algorithm to move partially dead code, so expressions are evaluated only where they will eventually be used.