[llvm] [LangRef] inline asm: the instructions are treated opaquely (PR #157080)

[Jacob Lifshay via llvm-commits]

programmerjake wrote:

> What about something like this?

looks good, though you should probably explicitly mention that empty strings can't be assumed to have no effect, there can be hardware-specific mechanisms to trap and change state there even if there are no instructions that can be overwritten there. also it's conventionally used as a compiler barrier.

https://github.com/llvm/llvm-project/pull/157080