How many ways to set a register to zero?

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There are a lot of possibility how to mov 0 in to ax under IA32…

    lea eax, [0]
    mov eax, 0FFFF0000h         //All constants form 0..0FFFFh << 16
    shr  ax, 16                 //All constants form 16..31
    shl eax, 16                 //All constants form 16..31

And perhaps the most strange… 🙂

@movzx:
    movzx eax, byte ptr[@movzx + 6]   //Because the last byte of this instruction is 0

and also in 32-bit mode (longer instruction puts the final (most-significant) address byte later)…

  @movzx:
    movzx ax, byte ptr[@movzx + 7]

Edit:

And for 16 bit x86 cpu mode, not tested…:

    lea  ax, [0]

and…

  @movzx:
    movzx ax, byte ptr cs:[@movzx + 7]   //Check if 7 is right offset

The cs: prefix is optional in case that the ds segment register is not equal to cs segment register.

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