I have a problem with classifying certain CPUs to the proper classes of Flynn's Taxonomy.
1. Zilog Z80
a limited ability for SIMD (Single Instruction, Multiple Data) with instructions to perform copy, compare, input, and output over contiguous blocks of memory;
For what I understand, Z80 is usually behaving as a SISD but when it comes to performing thing like copying or comparing Z80 is able to process multiple data using a single instruction.
How should we classify Z80 then? Is the ability to become SIMD processor a voice for or against saying that Z80 implements SIMD architecture?
2. Intel i5 (Dual core)
Form what I understand, we classify multicore CPUs as MIMD.
Is it as simple as that?
3. ARM Cortex-A15 (single core)
I'd classify the architecture of this processor as a SIMD model. Wikipedia says that it has superscalar pipeline, but as we know from Why is a superscalar processor SIMD? that multiple pipelines does not imply MIMD model.
Are "modern" single cores usually implementing SIMD model or not?