How do you multiply two 64bit numbers in Assembly?
As the title states, I need to multiply two 64bit numbers in Assembly, or two 16digit hexidecimal numbers. 

Help please? I'm only allowed to use registers %eax, %ebx, %ecx, %edx, and the stack.
How do you multiply two 64bit numbers in Assembly?
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As the title states, I need to multiply two 64bit numbers in Assembly, or two 16digit hexidecimal numbers. 

Help please? I'm only allowed to use registers %eax, %ebx, %ecx, %edx, and the stack.