question: static Operand equivalentValforPHI ( Instruction phi ) { if ( ! Phi . conforms ( phi ) ) return null ; Operand result = Phi . getResult ( phi ) , equiv = result ; int i = 0 , n = Phi . getNumberOfValues ( phi ) ; while ( i < n ) { equiv = Phi . getValue ( phi , i ++ ) ; if ( ! equiv . similar ( result ) ) break ; } while ( i < n ) { Operand opi = Phi . getValue ( phi , i ++ ) ; if ( ! opi . similar ( equiv ) && ! opi . similar ( result ) ) return null ; } return equiv ; }
target:  Try to find an operand that is equivalent to the result of a given phi instruction.