\brief Try to find a SUBPIECE operation producing the value in \b this from the given \b whole Varnode The amount of truncation producing \b this must be known apriori. Allow for COPY and MULTIEQUAL operations in the flow path from \b whole to \b this. This method will search recursively through branches of MULTIEQUAL up to a maximum depth. \param leastByte is the number of least significant byt
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