The x86 architecture includes an instruction called decimal adjust aft

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Module 2: x86 Architecture, CPU Control, I/O, Memory System Design

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The x86 architecture includes an instruction called decimal adjust after addition (DAA). DAA performs the following sequence of instructions:

if((AL AND 0FH) > 9) OR (AF = 1) then
    AL ← AL + 6;
    AF ← 1;
else
    AF ← 0;
endif;
if(AL > 9FH) OR (CF = 1) then
    AL ← AL + 60H;
    CF ← 1;
else
    CF ← 0;
endif.

"H" indicates hexadecimal. AL is an 8-bit register that holds the result of addition of two unsigned 8-bit integers. AF is a flag set if there is a carry from bit 3 to bit 4 in the result of an addition. CF is a flag set if there is a carry from bit 7 to bit 8. Explain the function performed by the DAA instruction.

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