1. **In Theory** Support bgt, bnez, bgez and lui.

lui : The decode result of lui is almost the same as lw, except for MemToReg and SinExt.
      The write value comes from alu, which is 0 + (unsigned Extension) imm.
beq : zero
bgez: zero == 0 (?)
bgt : !result[31]
bnez: !zero