--------- begin snippet (from Paul Gilmartin) I believe what it intends to say is that the two's complement of the maximum negative number is not its algebraic negation. --------- end snippet
I agree with you, Paul, about the "algebraic negation" part of your reply. However, as perceived by the programmer, the LCR instruction does not ignore the carry out of the sign position. I also agree with your point about "knowledge of the hardware implementation". What matters is the behavior of the implementation as it relates to the outcome of the operation as stated in Principles of Operation. In general, there are many variations of machine implementations (think of out of order execution as an example) but which ultimately conform to the model as described in Principles of Operation. Bottom line: I agree with you.
