1. A machine readable medium comprising instructions, which when executed by one or more processors, cause the one or more processors to perform the following: (a) selecting one of a plurality of code blocks to be a current code block; (b) accessing a current list of local variables, wherein the current list is associated with the current code block; (c) determining a successor code block for the current code block, wherein the current code block falls through or branches to the successor code block; (d) accessing a successor list of local variables, wherein the successor list is associated with the successor code block; (e) selecting one of the local variables in the current list; (f) determining whether the selected local variable is also in the successor list; (g) determining whether the selected local variable has been ordered into a particular slot in the successor list when the selected local variable is in the successor list; (h) selecting a desired slot, when the selected local variable has not been ordered into a particular slot in the successor list; (i) ordering the selected local variable into the desired slot in the successor list; and (j) ordering the selected local variable into the same desired slot in the current list, when the selected local variable has not already been ordered into the desired slot in the current list.