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Test results for AMD Ryzen
Author: Lefty Date: 2017-07-13 02:41
Thanks for the answer.
I have another question. I am wondering why AVX-256 / AVX -512 is considered superior to AVX-128.
You can pack 2 AVX-128 instructions into one AVX-256 instruction (provided that the instructions are independent), but it will not necessarily execute faster. A CPU with one 256 bit SIMD unit can execute the AVX-256 instruction in one cycle, however a CPU with 2 128-bit SIMD units would just schedule the 2 AVX-128 instructions to execute simultaneously - also in one cycle. I don't see where the advantage is.
 
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