Like my sibling posted, the crazy CISCy instructions aren’t comparable because in general they were no faster than an equivalent sequence of simpler instructions. That’s not the case for permute; there are no “simpler” instructions that let you build an efficient permute. It’s one the fundamental building blocks for efficient vector code -- that’s why it’s shocking that it was added to SSE so late.
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Like my sibling posted, the crazy CISCy instructions aren’t comparable because in general they were no faster than an equivalent sequence of simpler instructions. That’s not the case for permute; there are no “simpler” instructions that let you build an efficient permute. It’s one the fundamental building blocks for efficient vector code -- that’s why it’s shocking that it was added to SSE so late.