Mnemonic: TEST1 reg/mem,CL/immediate

          TEST1 r/m8,imm3 : 0F 18 [mod:000:r/m] imm  (4/13 clocks)
          TEST1 r/m16,CL  : 0F 11 [mod:000:r/m]      (3/12 clocks)
          TEST1 r/m16,imm4: 0F 19 [mod:000:r/m] imm  (4/13 clocks)