inline ASM function calling conventions.

[Sjoerd Nijboer via Digitalmars-d-learn]

I'm kinda puzzled.

I'm having trouble getting started with inline asm in D.
Suppowse I have the following:
void Foo(MyStrunct* first_arg, MyStrunct* second_arg)
{
    asm
    {
        naked;
        version(X86)
        {
            /* Do something with the content of I and J. */
        }
        version(X86_64)
        {
            /* Do something with the content of I and J. *?
        }
    }
}

void Bar()
{
    MyStrunct heapStructA, heapStructB;

    // do some initialization.

    Foo(heapStructA, heapStructB);
}

Suppose I would like to pass first_arg and second_arg by register 
to `Foo`, what calling convention should I use? I'm having 
trouble identifying the correct calling convention I should be 
using for X86 and X86_64 in D.

I've tried a couple using https://godbolt.org/ and DMD parameters 
'-g -m32', but I can't seem to find any that will pass by 
register. Is there one? Will it also work for LDC and GDC?