A lookupswitch or tableswitch can be used if all conditions are equality
checks to constants. To be more specific, it can be done if:
1. All conditions are CALL 'EQEQ(Any?, Any?)': Boolean
2. All types of variables involved in comparison are in the same group
of Char/Byte/Short/Int, String or enum.
3. All arg0 refer to the same value.
4. All arg1 are IrConst<*>.
Change-Id: Ifd7cb618395f6c5cc64601018b446f0bb7f5891c
