Re: Clever ways to hide a compare


Robert Redelmeier, Keyser Soze,

| > There are a few opcodes that don't affect the carry flag
| > even though they look they should, especially the NEG opcode.
|
| Some of this may be to facilitate porting from the 8080 or 8085.
|
| Equally historical, the carry flag is often left untouched in
| things like INC & DEC to make multiple precision arithmetic
| (usually involving looping) easier.

Right, find a compact list of all instructions which alter/clear/set
flags in the Appendix of the AMD64 manuals.
At least valid for all IA-32 and EMT/AMD64 CPUs.

__
wolfgang


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