158:, the overflow flag is meaningless and normally ignored. One of the advantages of two's complement arithmetic is that the addition and subtraction operations do not need to distinguish between signed and unsigned operands. For this reason, most computer instruction sets do not distinguish between signed and unsigned operands, generating both (signed) overflow and (unsigned) carry flags on every operation, and leaving it to following instructions to pay attention to whichever one is of interest.
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encoding of −2, a negative number. A negative sum of positive operands (or vice versa) is an overflow. The overflow flag would then be set so the program can be aware of the problem and mitigate this or signal an error. The overflow flag is thus set when the most significant bit (here considered the
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result would not fit in the number of bits used for the result. Some architectures may be configured to automatically generate an exception on an operation resulting in overflow.
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Internally, the overflow flag is usually generated by an
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209:"Overflow Detection: Signed Numbers Addition"
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111:Learn how and when to remove this message
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242:DAT 2343 Computer Systems Architecture
213:CIS77 Introduction to Computer Systems
131:) is usually a single bit in a system
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49:adding citations to reliable sources
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194:References
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85:scholar
454:Opcode
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