什么是汇编例程，以及如何在Go中使用它？

Question

I am reading a Go tutorial (The Way To Go), and it mentions something about assembly routine, can somebody please explain what is that? It also states about implemented 'outside' Go, and also no body... may I know what is the purpose?

Quote as follow:

To declarer[sic] a function implemented outside Go, such as an assembly routine, you simply give the name and signature, and no body:

func flushICache(begin, end uintptr) // implemented externally

I tried to search online, but it seems hard to find any tutorial regarding assembly routine, what is that alien? And, what is the meaning of implemented outside Go?

Answer 1

Please read this and follow the links there.

To cite it

Machine code or machine language is a set of instructions executed directly by a computer's central processing unit (CPU). Each instruction performs a very specific task, such as a load, a jump, or an ALU operation on a unit of data in a CPU register or memory.

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All practical programs today are written in higher-level languages or assembly language.

The Go's own reference doc on its support for assembler is this.