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Dead Code Elimination (DCE)  is an optimization
technique to eliminate some variables not used at all.
An overall construct generates 6 variables outside the loop
according to the naive translation scheme. Since these control
variables are often unused, and the methods are specialized methods
known to the compiler--side effect free--we don't have any side
effects from applying DCE with data flow analysis to them.
Dead Code Elimination
We assume that DCE should be applied after all optimization techniques
we discussed earlier.
Moreover, we assume we narrow the target of DCE for the HPJava
optimization strategy. That is, for the moment, DCE will target only
control variables and control scripts for overall constructs.