How to inline x64 asm in vs2017 ?

[gigaman]

Does one call or jump really matter?
I mean, if you said you couldn't easily access local variables or structures, I'd agree... but "excessive call", it sounds like you are trying to optimize something. In that case inline assembler is hardly any good - it's a blackbox for the compiler (at least for the Microsoft's) so it has to dump the values from registers into local variables and after the inline assembly load them back. In other words, a piece of inline assembly heavily breaks the optimization of the surrounding C code - so it's usually not worth it, it does more damage than one call would (so it's better to write the whole CPU intensive piece of code in assembler as a separate function).