mmx – Tarik Billa

difference between MMX and XMM register?

September 12, 2023 by Tarik

MM registers are the registers used by the MMX instruction set, one of the first attempts to add (integer-only) SIMD to x86. They are 64 bit wide and they are actually aliases for the mantissa parts of the x87 registers (but they are not affected by the FPU top of the stack position); this was … Read more

Are different mmx, sse and avx versions complementary or supersets of each other?

August 9, 2023 by Tarik

They are complementary. Each new instruction set extension add new instructions and eventually a new programming model (new registers for example). None are deprecated, deprecating instructions is almost impossible to do for compatibility reasons. However some optional extensions may be absent or removed from newer models (like the FMA4 of AMD) if not very wide … Read more