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Re: Preventing x86 instruction length optimizations
* Jan Beulich:
>>Is there any easy way to force the
>>long instruction encoding, short of using .byte?
>
> Not that I know of. But I also can't see the general need for something
> like that...
It's useful for loop unrolling. If you can control the instruction
lengths (so that each expanded iteration takes the same number of
bytes), you can use a computed jump to skip into the loop at the
correct position. Otherwise, you need a cascade of conditional
branches.