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I am currently studying computer-science, and i was really thinking about this question:

Is it possible to divide/split an instruction to more than four-subinstructions?

Please help, and also comment down why it is or isnt possible to divide/split an instruction to more than four-subinstructions?

I thank you in advance :)

Letsgox
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    What are the constraints? As a general topic, most all problems can be decomposed into further detail, and the decompositions themselves further decomposed, and so on. Without employing constraints, we can decompose with abandon. There's no magic limit at 4 items. – Erik Eidt Oct 15 '22 at 12:50
  • I am referring to processors in machines. When it comes to bits, and also if a complicated instruction can split into four or more sub-instructions that will carry x amount of bits – Letsgox Oct 15 '22 at 14:00
  • Clearly yes, if you look at how some x86 CPUs run some instructions, some decode to more than 4 micro-ops (aka uops). e.g. `adc [rdi], eax` is 6 back-end uops on most Intel CPUs (see [Andy Glew's explanation [quoted in a section of this answer](https://stackoverflow.com/a/32258855/224132), or an unbounded number for special cases like `rep movsb` (memmove). See https://uops.info/ and https://agner.org/optimize/ for tables. The `loop` instruction is slow on many CPUs: [Why is the loop instruction slow? Couldn't Intel have implemented it efficiently?](https://stackoverflow.com/q/35742570) – Peter Cordes Oct 17 '22 at 06:48
  • When you're talking about "carry x amount of bits", it sounds like you're thinking of packing multiple separate instructions into one big instruction, like a VLIW. There is of course no limit on how big a VLIW instruction word can be. [Are SIMD and VLIW instructions the same thing?](https://stackoverflow.com/q/70400206) has some links about what VLIW is, and some ISAs that used it. – Peter Cordes Oct 17 '22 at 06:50

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