It's AMD's definition, you have simply accepted it. Try and find me a computer science source that agrees with that definition. You won't, because before now because instruction fetch and retire were traditionally considered part of the core.
I agree that it is more flexible and I like that design. But being flexible doesn't mean that it is really two separate FP units. Take away one half and it wouldn't be able to process 256-bit instructions. It is designed to be ganged together to process them. One half can't do half a 256-bit instruction in two steps, that would require a redesign of the FP unit.Yes it is.
Sharing the FP scheduler (capable of handling two threads of FP micro-ops simultaneously) is just more flexible than two independent schedulers, AND uses less transistors.
Yes it can.
It just means it has to take two cycles to process each 128-bit micro-op.
From John Fruehe's FlexFP article:
The beauty of the Flex FP is that it is a single 256-bit FPU that is shared by two integer cores.




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