Sorry, somewhat of a tangent but regarding:
> The %0 and %1 are positional references into a list you have to count by hand.
You can name your operands in gcc inline assembly.
https://gcc.gnu.org/onlinedocs/gcc/Extended-Asm.html#Output-...
Look for "asmSymbolicName".
On a phone so not checking if it builds, but something like `asm("add %[my_out], %[my_in], #3":[my_out]"=r"(outvar):[my_in]"r"(invar):);`.
The equivalent Odin syntax looks like this:
add_three :: asm(my_in: u64) -> (my_out: u64) { add my_out, my_in, 3 }
out_var = add_three(in_var)
Which is already infinitely more readable and requires no parochial sigils nor the arcane clobbering syntax.