What is the state of D with Android/iOS

[Rishub Nagpal via Digitalmars-d]

On Wednesday, 25 February 2015 at 08:04:02 UTC, Joakim wrote:
> On Tuesday, 24 February 2015 at 21:20:24 UTC, Rishub Nagpal 
> wrote:
>> On Tuesday, 24 February 2015 at 19:34:15 UTC, Joakim wrote:
>>> I need to patch llvm in a similar way to that dmd PR, so that 
>>> Android/ARM can use the same scheme.  It appears that Dan did 
>>> something similar with his patched llvm for iOS.
>>>
>>> As for your linked Android patches, that might be possible 
>>> but would be pointless unless you are only deploying to a 
>>> device you patched the OS for.  Better to patch llvm to 
>>> support the same TLS scheme used for Android/x86.
>>
>> Interesting. A few others and I were talking about getting
>> Android/ARM to function with LDC today. I'll be sure to keep up
>> to date with your work!
>
> The remaining piece is to insert the correct function call to 
> ___tls_get_addr when TLS variables are accessed, ie the 
> equivalent to this patch for dmd's backend needs to be created 
> for llvm:
>
> https://github.com/joakim-noah/dmd/commit/477f52cffb0d8bd1a698dd33ad7e2e66d9fa62ca#diff-d427199c5cd504da634c0c42fc2b3371
>
> I've been putting off looking into llvm's internals enough to 
> write that for a while now.  If you or anybody else knows llvm 
> better, feel free to take it.  The remaining changes needed are 
> in this small patch for llvm:
>
> https://gist.github.com/joakim-noah/1fb23fba1ba5b7e87e1a

Why exactly do we need to insert that TLS function call? 
Shouldn't Android/ARM follow the normal ELF logic? I am not 
really sure what Dan Olsen did here:

https://github.com/smolt/llvm/commit/42c2d7057b62454bb466abe8d146dd3c717e2cc5

Is he creating a iOS TLS ABI?


I have spent the last week doing heavy research, and I am not 
sure if I really understand the problem

Do you have any references or documented code I can read to 
better understand what exactly is going on?