If a defendant has been convicted of three or more felonies in addition to the principal felony and one or more of the prior felony convictions was for a crime of violence as defined in subdivision 22-1-2(9), the sentence for the principal felony shall be enhanced to the sentence for a Class C felony. Source: SDC 1939, § 13.0611; SDCL, § 22-7-1 ; SL 1976, ch 158 , § 7-3 ; SL 1977, ch 189 , § 19; SL 1981, ch 13 , § 4; SL 1984, ch 166 , § 1; SL 2005, ch 120 , § 384.