[junon]

I've thought about this very question for years. My answer has been, usually, "no" for all cases that do not allow the developer to write straight assembly.

That is, until things like C++'s stackless coroutines came about, which are a construct intrinsic to the compiler and not functionality directly exposed by C.

Further, any machine code language is going to allow you specific instruction access that a compiler might not otherwise utilize (rare, but it happens). In such cases you can gain 'manual' speedups over what C could allow you to do. I would hope that is the obvious exception, however.

But you are asking a very good question not a lot of developers are willing to think much about.