How to map machine instctions in memory and execute them? (Aka, how to create a loader)

[rempas]

On Monday, 6 June 2022 at 18:05:23 UTC, Johan wrote:
> This instruction is wrong. Note that you are writing twice to 
> RDX, but also that you are using `mov sign_extend imm32, reg64` 
> instead of `mov imm64, reg64` (`0x48 0xBA`?). Third, why append 
> an extra zero (`*cast(char*)(code + 32) = 0x00;`)? That must be 
> a bug too.
>
> cheers,
>   Johan

Thanks! It seems that there is probably a "typo" from the 
original [source](https://github.com/vishen/go-x64-executable) 
that I got the code. The hex values are different however so 
there is only a mistake in the comment, the code normally works 
in the example repository (and I made a D version that works 
too). The padding in the end seems to be necessary else the 
example doesn't compile (I don't know why, I'm SUPER n00b when it 
comes to machine language, I don't know almost anything!). I'm 
also not sure how the "encode" will be for `mov imm64, reg64` as 
I tried to type what you typed in the parenthesis and it doesn't 
seem to work.