'peel' - duplicates loops body moving first iteration out of the loop.
Loop peeling moves one or more iterations to the loop header to reduce the looping overhead for a small loop count and to enable optimizations in peeled iterations.
It worth to perform hash value numbering after peel pass.
header file: http://svn.apache.org/viewvc/harmony/enhanced/drlvm/trunk/vm/jitrino/src/optimizer/Loop.h
implementation file: http://svn.apache.org/viewvc/harmony/enhanced/drlvm/trunk/vm/jitrino/src/optimizer/Loop.cpp