How to implement saturation instructions in ARMv8 architecture?

Thank you Peter for replying. I know it is pretty straightforward in C but I want to implement it in assembly and that too in ARMv8 architecture. The thing is that in ARMv7 we have a single instruction for that i.e. QADD. But we don't have such instruction in v8 so we need to use neon instruction such as SQADD. Do we have a single instruction to perform such operation in v8?

Thank you Peter for replying. I know it is pretty straightforward in C but I want to implement it in assembly and that too in ARMv8 architecture. The thing is that in ARMv7 we have a single instruction for that i.e. QADD. But we don't have such instruction in v8 so we need to use neon instruction such as SQADD. Do we have a single instruction to perform such operation in v8?

Ah, sorry, I missed the intent of your question.

The only way to perform saturation in a single instruction is using the SIMD&FP instructions. They do have scalar variants (effectively ignoring all but a single lane - including for flag setting,) but they still operate on the FP register bank and set flags in FPSR rather than PSTATE.