[Harmony Wiki] Update of "Jitrino OPT/btr" by Mikhail Fursov

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The following page has been changed by Mikhail Fursov:
http://wiki.apache.org/harmony/Jitrino_OPT/btr

New page:
''' 'btr' ''' LIR transformation replaces branch instructions with conditional CMOVcc or SETcc instructions
[[BR]]
The algorithm takes one-pass over CFG.
[[BR]]
The transformation allows to reduce count of branches and is recommended to be inserted before other LIR transformations
[[BR]]

The algorithm works as follows:    
{{{
     1)    Finds branch instruction which performs branch to basic blocks with
         only instructions MOV with the same def-operand.
 
     2)    If each of thus blocks has only one predecessor they and branch 
         instruction is replaced with conditional instruction
 }}}