Support for allocation of executable memory

[Glavo]

I don't think Panama should provide special support for it.

To do this, you just need to create the binding of the relevant system API
(e.g. `VirtualAlloc` and `VirtualProtect` on Windows, or `mmap` on Linux)
with the foreign linker API and call it.

Felix Cravic <themode at outlook.fr> 于2021年11月22日周一 上午1:01写道：

> Hello, I was wondering if there has ever been any discussion about
> supporting allocation of executable memory (and then its execution). The
> use cases I have in mind are emulation, very hot paths requiring
> specialized assembly (which could still fallback to jvm bytecode if
> unavailable), and a potential option to keep the whole application written
> in a JVM language.
>
> I doubt that such addition would drastically change the API, perhaps some
> concern about OS specific restrictions (e.g. write-xor-execute memory
> protection), and platform not supporting JIT compilation at all (IOS,
> potentially problematic for Graal & project Leyden)
>
> Discussion would be appreciated!
>