3 ms·
No, x87/MMX and SSE XMM were not aliased. They were two separate register files. (You may be confusing it with XMM vs YMM vs ZMM, i.e. SSE vs AVX vs AVX512.)
by 245425456g 2mo ago
No, x87/MMX and SSE XMM were not aliased. They were two separate register files.
(You may be confusing it with XMM vs YMM vs ZMM, i.e. SSE vs AVX vs AVX512.)
- deaddodo 2mo agoIt’s more likely they’re confusing it with 3DNow! (AMD’s own media extension focused on floating point math). That was strictly aliased and therefore an either/or situation on chips that had both.
- 45t345tg35 2mo agoSure, 3DNow! operated on MMX registers. But the OP was talking about Intel's P3... so 3DNow! wasn't a factor...
- deaddodo 2mo agoI think we’re agreeing. I think they’re mixing up the 3DNow introduction with the SSE one and conflating them into one. SSE never had aliasing, so OP’s comment is strictly incorrect either way.