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Pragma · 08-10-2004, 05:28 PM

If you're trying to exchange two values, the best way to do that is three XOR operations.

xorl %eax, %edx
xorl %ebx, %eax
xorl %eax, %edx

However, the thing to pay attention to is the list of legal operands:
src dst
idata reg
idata mem
reg reg
mem reg
reg mem

So I think what you'd have to do is move both pieces of data from the array to registers, XOR them, then move them back.

However, now that I put more thought into it, that might not answer your solution. I'll give it some more thought.

08-10-2004, 05:28 PM	#2 (permalink)
Pragma I am Winter Born Location: Alexandria, VA	If you're trying to exchange two values, the best way to do that is three XOR operations. xorl %eax, %edx xorl %ebx, %eax xorl %eax, %edx However, the thing to pay attention to is the list of legal operands: src dst idata reg idata mem reg reg mem reg reg mem So I think what you'd have to do is move both pieces of data from the array to registers, XOR them, then move them back. However, now that I put more thought into it, that might not answer your solution. I'll give it some more thought. __________________ Eat antimatter, Posleen-boy!