3 ms·

if I write a bit of software and target ARM64 and it cannot run on x86. Does that mean that x86 has a specific purpose now and is no longer a general purpose C

if I write a bit of software and target ARM64 and it cannot run on x86. Does that mean that x86 has a specific purpose now and is no longer a general purpose CPU?

gary_0 3y ago
That's not the same thing. An instruction set is an inherent aspect of a CPU; you can't have a CPU without one. Also, you can emulate or translate instruction sets between general-purpose CPUs, or in most cases just recompile the higher-level source code. The underlying logic will be executed regardless.
- throwaway2990 3y ago
  Oh so you’re saying the iPhone cpu is a general purpose cpu then. Just need to translate the instructions. Ok.
- inkyoto 3y ago
  > […] An instruction set is an inherent aspect of a CPU; you can't have a CPU without one. Oh, yes, you can. The following examples of – Transport triggered architecture – Dataflow architecture – Optical and quantum computing represent viable, general purpose (not general availability), albeit experimental, CPU's without instruction sets. That is, none of them have anything similar to «movq $1, %r0» or «add.w %r2, %r0, %r1». FPGA's are another and a more conventional example of a general purpose (even if specialised) CPU without an instruction set.
- kaba0 3y ago
  Tada, there is ish, so you can run whatever on an iphone emulated by an x86 layer! That is, you have a general purpose CPU. Sure, apple suck at sideloading, hopefully the EU ruling will make it a possibility, but then say that instead.
  - diffeomorphism 3y ago
    > Tada, you can but only after jailbreaking and replacing your actual hardware with a virtual one. That sounds like these "technically, a taco is a sandwich" discussions. Maybe, but was that actually the question?
    - the_lucifer 3y ago
      ISH does not need a jailbreak. you just download it from the App Store.
belltaco 3y ago
An ARM64 emulator will run that software on x86.

if I write a bit of software and target ARM64 and it cannot run on x86. Does that mean that x86 has a specific purpose now and is no longer a general purpose CPU?

gary_0 3y ago

That's not the same thing. An instruction set is an inherent aspect of a CPU; you can't have a CPU without one. Also, you can emulate or translate instruction sets between general-purpose CPUs, or in most cases just recompile the higher-level source code. The underlying logic will be executed regardless.

throwaway2990 3y ago
Oh so you’re saying the iPhone cpu is a general purpose cpu then. Just need to translate the instructions. Ok.
inkyoto 3y ago
> […] An instruction set is an inherent aspect of a CPU; you can't have a CPU without one. Oh, yes, you can. The following examples of – Transport triggered architecture – Dataflow architecture – Optical and quantum computing represent viable, general purpose (not general availability), albeit experimental, CPU's without instruction sets. That is, none of them have anything similar to «movq $1, %r0» or «add.w %r2, %r0, %r1». FPGA's are another and a more conventional example of a general purpose (even if specialised) CPU without an instruction set.
kaba0 3y ago
Tada, there is ish, so you can run whatever on an iphone emulated by an x86 layer! That is, you have a general purpose CPU. Sure, apple suck at sideloading, hopefully the EU ruling will make it a possibility, but then say that instead.
- diffeomorphism 3y ago
  > Tada, you can but only after jailbreaking and replacing your actual hardware with a virtual one. That sounds like these "technically, a taco is a sandwich" discussions. Maybe, but was that actually the question?
  - the_lucifer 3y ago
    ISH does not need a jailbreak. you just download it from the App Store.

belltaco 3y ago

An ARM64 emulator will run that software on x86.