11111110 (decimal 254 decimal). Since there is carry out of bit 7 (the eighth bit), the carry is set, indicating that the result needs 9 bits. The valid 9-bit result is the concatenation of the carry flag with the result.

The other common ALU status register bits will be Sign_Flag set, Zero_flag clear, and Overflow_Flag clear.

If 11111111 represents two's complement signed integer -1 (x86 instruction ADD al,-1),

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