F6 /5 IMUL r/m8* MValid Valid AX←AL ∗ r/mbyte.
F7 /5 IMUL r/m16 MValid Valid DX:AX ←AX ∗ r/mword.
F7 /5 IMUL r/m32 MValid Valid EDX:EAX ←EAX ∗ r/m32.
REX.W + F7 /5 IMUL r/m64 M Valid N.E. RDX:RAX ←RAX ∗ r/m64.
0F AF /r IMUL r16, r/m16 RM Valid Valid word register ←word register ∗ r/m16.
0F AF /r IMUL r32, r/m32 RM Valid Valid doubleword register ←doubleword register ∗
r/m32.
REX.W + 0F AF /r IMUL r64, r/m64 RM Valid N.E. Quadword register ←Quadword register ∗
r/m64.
6B /r ib IMUL r16, r/m16, imm8 RMI Valid Valid word register ← r/m16 ∗sign-extended
immediate byte.
6B /r ib IMUL r32, r/m32, imm8 RMI Valid Valid doubleword register ← r/m32 ∗signextended immediate byte.
REX.W + 6B /r ib IMUL r64, r/m64, imm8 RMI Valid N.E. Quadword register ← r/m64 ∗sign-extended
immediate byte.
69 /r iw IMUL r16, r/m16, imm16 RMI Valid Valid word register ← r/m16 ∗immediate word.
69 /r id IMUL r32, r/m32, imm32 RMI Valid Valid doubleword register ← r/m32 ∗immediate
doubleword.
REX.W + 69 /r id IMUL r64, r/m64, imm32 RMI Valid N.E. Quadword register ← r/m64 ∗immediate
doubleword.
NOTES:

当要与立即数相乘的时候就必须三个操作数，

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