How to mirror bytes without using other registers?

Question

Say I have this byte in AL: 01100001 After applying the mirror function, I want the byte to be 10000110.

All the ideas that I came up with, I should use other registers, but I'm curious if there is a way to reflect a byte without using any other register?

Answer 1

Option "storage by immediate code":

mirror_bits:
    ; handle bits 0 and 7
    TEST    al,0x81
    JPE     bits07same
    XOR     al,0x81
bits07same:
    ; handle bits 1 and 6
    TEST    al,0x42
    JPE     bits16same
    XOR     al,0x42
bits16same:
    ; handle bits 2 and 5
    TEST    al,0x24
    JPE     bits25same
    XOR     al,0x24
bits25same:
    ; handle bits 3 and 4
    TEST    al,0x18
    JPE     bits34same
    XOR     al,0x18
bits34same:
    RET

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EDIT: About my comment on the question and the general answer, is there any way.

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