Accumulators
The EAX register is also known as an accumulator and is used with multiplication and division operations, both as implied and target operands. It is important to mention that the result of a binary multiplication is twice the size of the operands and the result of a binary division consists of two parts (quotient and remainder), each of which has the same bit width as the operands. Since the x86 architecture began with 16-bit registers and for the sake of backward compatibility, the EDX register is used for storing partial results when the values of the operands are larger than could fit into 8 bits. For example, if we want to multiply two bytes, 0x50 and 0x04, we would expect the result to be 0x140, which cannot be stored in ...
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