What is the practical difference between the SI and DI registers?

assembly x86 cpu-registers
tatsuhirosatou picture tatsuhirosatou · Sep 27, 2009 · Viewed 52.5k times · Source

I don't get what is the difference.

Answer

Pierre Bourdon picture Pierre Bourdon · Sep 27, 2009

When you are using instructions like movsb, si is considered as the source register, while di is considered as the destination register. But they are both normal x86 registers.

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